src/src/expand.c

   1 /*************************************************
   2 *     Exim - an Internet mail transport agent    *
   3 *************************************************/
   4
   5 /* Copyright (c) University of Cambridge 1995 - 2018 */
   6 /* See the file NOTICE for conditions of use and distribution. */
   7
   8
   9 /* Functions for handling string expansion. */
  10
  11
  12 #include "exim.h"
  13
  14 /* Recursively called function */
  15
  16 static uschar *expand_string_internal(const uschar *, BOOL, const uschar **, BOOL, BOOL, BOOL *);
  17 static int_eximarith_t expanded_string_integer(const uschar *, BOOL);
  18
  19 #ifdef STAND_ALONE
  20 # ifndef SUPPORT_CRYPTEQ
  21 #  define SUPPORT_CRYPTEQ
  22 # endif
  23 #endif
  24
  25 #ifdef LOOKUP_LDAP
  26 # include "lookups/ldap.h"
  27 #endif
  28
  29 #ifdef SUPPORT_CRYPTEQ
  30 # ifdef CRYPT_H
  31 #  include <crypt.h>
  32 # endif
  33 # ifndef HAVE_CRYPT16
  34 extern char* crypt16(char*, char*);
  35 # endif
  36 #endif
  37
  38 /* The handling of crypt16() is a mess. I will record below the analysis of the
  39 mess that was sent to me. We decided, however, to make changing this very low
  40 priority, because in practice people are moving away from the crypt()
  41 algorithms nowadays, so it doesn't seem worth it.
  42
  43 <quote>
  44 There is an algorithm named "crypt16" in Ultrix and Tru64.  It crypts
  45 the first 8 characters of the password using a 20-round version of crypt
  46 (standard crypt does 25 rounds).  It then crypts the next 8 characters,
  47 or an empty block if the password is less than 9 characters, using a
  48 20-round version of crypt and the same salt as was used for the first
  49 block.  Characters after the first 16 are ignored.  It always generates
  50 a 16-byte hash, which is expressed together with the salt as a string
  51 of 24 base 64 digits.  Here are some links to peruse:
  52
  53         http://cvs.pld.org.pl/pam/pamcrypt/crypt16.c?rev=1.2
  54         http://seclists.org/bugtraq/1999/Mar/0076.html
  55
  56 There's a different algorithm named "bigcrypt" in HP-UX, Digital Unix,
  57 and OSF/1.  This is the same as the standard crypt if given a password
  58 of 8 characters or less.  If given more, it first does the same as crypt
  59 using the first 8 characters, then crypts the next 8 (the 9th to 16th)
  60 using as salt the first two base 64 digits from the first hash block.
  61 If the password is more than 16 characters then it crypts the 17th to 24th
  62 characters using as salt the first two base 64 digits from the second hash
  63 block.  And so on: I've seen references to it cutting off the password at
  64 40 characters (5 blocks), 80 (10 blocks), or 128 (16 blocks).  Some links:
  65
  66         http://cvs.pld.org.pl/pam/pamcrypt/bigcrypt.c?rev=1.2
  67         http://seclists.org/bugtraq/1999/Mar/0109.html
  68         http://h30097.www3.hp.com/docs/base_doc/DOCUMENTATION/HTML/AA-Q0R2D-
  69              TET1_html/sec.c222.html#no_id_208
  70
  71 Exim has something it calls "crypt16".  It will either use a native
  72 crypt16 or its own implementation.  A native crypt16 will presumably
  73 be the one that I called "crypt16" above.  The internal "crypt16"
  74 function, however, is a two-block-maximum implementation of what I called
  75 "bigcrypt".  The documentation matches the internal code.
  76
  77 I suspect that whoever did the "crypt16" stuff for Exim didn't realise
  78 that crypt16 and bigcrypt were different things.
  79
  80 Exim uses the LDAP-style scheme identifier "{crypt16}" to refer
  81 to whatever it is using under that name.  This unfortunately sets a
  82 precedent for using "{crypt16}" to identify two incompatible algorithms
  83 whose output can't be distinguished.  With "{crypt16}" thus rendered
  84 ambiguous, I suggest you deprecate it and invent two new identifiers
  85 for the two algorithms.
  86
  87 Both crypt16 and bigcrypt are very poor algorithms, btw.  Hashing parts
  88 of the password separately means they can be cracked separately, so
  89 the double-length hash only doubles the cracking effort instead of
  90 squaring it.  I recommend salted SHA-1 ({SSHA}), or the Blowfish-based
  91 bcrypt ({CRYPT}$2a$).
  92 </quote>
  93 */
  94
  95
  96
  97 /*************************************************
  98 *            Local statics and tables            *
  99 *************************************************/
 100
 101 /* Table of item names, and corresponding switch numbers. The names must be in
 102 alphabetical order. */
 103
 104 static uschar *item_table[] = {
 105   US"acl",
 106   US"authresults",
 107   US"certextract",
 108   US"dlfunc",
 109   US"env",
 110   US"extract",
 111   US"filter",
 112   US"hash",
 113   US"hmac",
 114   US"if",
 115 #ifdef SUPPORT_I18N
 116   US"imapfolder",
 117 #endif
 118   US"length",
 119   US"listextract",
 120   US"lookup",
 121   US"map",
 122   US"nhash",
 123   US"perl",
 124   US"prvs",
 125   US"prvscheck",
 126   US"readfile",
 127   US"readsocket",
 128   US"reduce",
 129   US"run",
 130   US"sg",
 131   US"sort",
 132 #ifdef EXPERIMENTAL_SRS_NATIVE
 133   US"srs_encode",
 134 #endif
 135   US"substr",
 136   US"tr" };
 137
 138 enum {
 139   EITEM_ACL,
 140   EITEM_AUTHRESULTS,
 141   EITEM_CERTEXTRACT,
 142   EITEM_DLFUNC,
 143   EITEM_ENV,
 144   EITEM_EXTRACT,
 145   EITEM_FILTER,
 146   EITEM_HASH,
 147   EITEM_HMAC,
 148   EITEM_IF,
 149 #ifdef SUPPORT_I18N
 150   EITEM_IMAPFOLDER,
 151 #endif
 152   EITEM_LENGTH,
 153   EITEM_LISTEXTRACT,
 154   EITEM_LOOKUP,
 155   EITEM_MAP,
 156   EITEM_NHASH,
 157   EITEM_PERL,
 158   EITEM_PRVS,
 159   EITEM_PRVSCHECK,
 160   EITEM_READFILE,
 161   EITEM_READSOCK,
 162   EITEM_REDUCE,
 163   EITEM_RUN,
 164   EITEM_SG,
 165   EITEM_SORT,
 166 #ifdef EXPERIMENTAL_SRS_NATIVE
 167   EITEM_SRS_ENCODE,
 168 #endif
 169   EITEM_SUBSTR,
 170   EITEM_TR };
 171
 172 /* Tables of operator names, and corresponding switch numbers. The names must be
 173 in alphabetical order. There are two tables, because underscore is used in some
 174 cases to introduce arguments, whereas for other it is part of the name. This is
 175 an historical mis-design. */
 176
 177 static uschar *op_table_underscore[] = {
 178   US"from_utf8",
 179   US"local_part",
 180   US"quote_local_part",
 181   US"reverse_ip",
 182   US"time_eval",
 183   US"time_interval"
 184 #ifdef SUPPORT_I18N
 185  ,US"utf8_domain_from_alabel",
 186   US"utf8_domain_to_alabel",
 187   US"utf8_localpart_from_alabel",
 188   US"utf8_localpart_to_alabel"
 189 #endif
 190   };
 191
 192 enum {
 193   EOP_FROM_UTF8,
 194   EOP_LOCAL_PART,
 195   EOP_QUOTE_LOCAL_PART,
 196   EOP_REVERSE_IP,
 197   EOP_TIME_EVAL,
 198   EOP_TIME_INTERVAL
 199 #ifdef SUPPORT_I18N
 200  ,EOP_UTF8_DOMAIN_FROM_ALABEL,
 201   EOP_UTF8_DOMAIN_TO_ALABEL,
 202   EOP_UTF8_LOCALPART_FROM_ALABEL,
 203   EOP_UTF8_LOCALPART_TO_ALABEL
 204 #endif
 205   };
 206
 207 static uschar *op_table_main[] = {
 208   US"address",
 209   US"addresses",
 210   US"base32",
 211   US"base32d",
 212   US"base62",
 213   US"base62d",
 214   US"base64",
 215   US"base64d",
 216   US"bless",
 217   US"domain",
 218   US"escape",
 219   US"escape8bit",
 220   US"eval",
 221   US"eval10",
 222   US"expand",
 223   US"h",
 224   US"hash",
 225   US"hex2b64",
 226   US"hexquote",
 227   US"ipv6denorm",
 228   US"ipv6norm",
 229   US"l",
 230   US"lc",
 231   US"length",
 232   US"listcount",
 233   US"listnamed",
 234   US"mask",
 235   US"md5",
 236   US"nh",
 237   US"nhash",
 238   US"quote",
 239   US"randint",
 240   US"rfc2047",
 241   US"rfc2047d",
 242   US"rxquote",
 243   US"s",
 244   US"sha1",
 245   US"sha2",
 246   US"sha256",
 247   US"sha3",
 248   US"stat",
 249   US"str2b64",
 250   US"strlen",
 251   US"substr",
 252   US"uc",
 253   US"utf8clean" };
 254
 255 enum {
 256   EOP_ADDRESS =  nelem(op_table_underscore),
 257   EOP_ADDRESSES,
 258   EOP_BASE32,
 259   EOP_BASE32D,
 260   EOP_BASE62,
 261   EOP_BASE62D,
 262   EOP_BASE64,
 263   EOP_BASE64D,
 264   EOP_BLESS,
 265   EOP_DOMAIN,
 266   EOP_ESCAPE,
 267   EOP_ESCAPE8BIT,
 268   EOP_EVAL,
 269   EOP_EVAL10,
 270   EOP_EXPAND,
 271   EOP_H,
 272   EOP_HASH,
 273   EOP_HEX2B64,
 274   EOP_HEXQUOTE,
 275   EOP_IPV6DENORM,
 276   EOP_IPV6NORM,
 277   EOP_L,
 278   EOP_LC,
 279   EOP_LENGTH,
 280   EOP_LISTCOUNT,
 281   EOP_LISTNAMED,
 282   EOP_MASK,
 283   EOP_MD5,
 284   EOP_NH,
 285   EOP_NHASH,
 286   EOP_QUOTE,
 287   EOP_RANDINT,
 288   EOP_RFC2047,
 289   EOP_RFC2047D,
 290   EOP_RXQUOTE,
 291   EOP_S,
 292   EOP_SHA1,
 293   EOP_SHA2,
 294   EOP_SHA256,
 295   EOP_SHA3,
 296   EOP_STAT,
 297   EOP_STR2B64,
 298   EOP_STRLEN,
 299   EOP_SUBSTR,
 300   EOP_UC,
 301   EOP_UTF8CLEAN };
 302
 303
 304 /* Table of condition names, and corresponding switch numbers. The names must
 305 be in alphabetical order. */
 306
 307 static uschar *cond_table[] = {
 308   US"<",
 309   US"<=",
 310   US"=",
 311   US"==",     /* Backward compatibility */
 312   US">",
 313   US">=",
 314   US"acl",
 315   US"and",
 316   US"bool",
 317   US"bool_lax",
 318   US"crypteq",
 319   US"def",
 320   US"eq",
 321   US"eqi",
 322   US"exists",
 323   US"first_delivery",
 324   US"forall",
 325   US"forall_json",
 326   US"forall_jsons",
 327   US"forany",
 328   US"forany_json",
 329   US"forany_jsons",
 330   US"ge",
 331   US"gei",
 332   US"gt",
 333   US"gti",
 334 #ifdef EXPERIMENTAL_SRS_NATIVE
 335   US"inbound_srs",
 336 #endif
 337   US"inlist",
 338   US"inlisti",
 339   US"isip",
 340   US"isip4",
 341   US"isip6",
 342   US"ldapauth",
 343   US"le",
 344   US"lei",
 345   US"lt",
 346   US"lti",
 347   US"match",
 348   US"match_address",
 349   US"match_domain",
 350   US"match_ip",
 351   US"match_local_part",
 352   US"or",
 353   US"pam",
 354   US"pwcheck",
 355   US"queue_running",
 356   US"radius",
 357   US"saslauthd"
 358 };
 359
 360 enum {
 361   ECOND_NUM_L,
 362   ECOND_NUM_LE,
 363   ECOND_NUM_E,
 364   ECOND_NUM_EE,
 365   ECOND_NUM_G,
 366   ECOND_NUM_GE,
 367   ECOND_ACL,
 368   ECOND_AND,
 369   ECOND_BOOL,
 370   ECOND_BOOL_LAX,
 371   ECOND_CRYPTEQ,
 372   ECOND_DEF,
 373   ECOND_STR_EQ,
 374   ECOND_STR_EQI,
 375   ECOND_EXISTS,
 376   ECOND_FIRST_DELIVERY,
 377   ECOND_FORALL,
 378   ECOND_FORALL_JSON,
 379   ECOND_FORALL_JSONS,
 380   ECOND_FORANY,
 381   ECOND_FORANY_JSON,
 382   ECOND_FORANY_JSONS,
 383   ECOND_STR_GE,
 384   ECOND_STR_GEI,
 385   ECOND_STR_GT,
 386   ECOND_STR_GTI,
 387 #ifdef EXPERIMENTAL_SRS_NATIVE
 388   ECOND_INBOUND_SRS,
 389 #endif
 390   ECOND_INLIST,
 391   ECOND_INLISTI,
 392   ECOND_ISIP,
 393   ECOND_ISIP4,
 394   ECOND_ISIP6,
 395   ECOND_LDAPAUTH,
 396   ECOND_STR_LE,
 397   ECOND_STR_LEI,
 398   ECOND_STR_LT,
 399   ECOND_STR_LTI,
 400   ECOND_MATCH,
 401   ECOND_MATCH_ADDRESS,
 402   ECOND_MATCH_DOMAIN,
 403   ECOND_MATCH_IP,
 404   ECOND_MATCH_LOCAL_PART,
 405   ECOND_OR,
 406   ECOND_PAM,
 407   ECOND_PWCHECK,
 408   ECOND_QUEUE_RUNNING,
 409   ECOND_RADIUS,
 410   ECOND_SASLAUTHD
 411 };
 412
 413
 414 /* Types of table entry */
 415
 416 enum vtypes {
 417   vtype_int,            /* value is address of int */
 418   vtype_filter_int,     /* ditto, but recognized only when filtering */
 419   vtype_ino,            /* value is address of ino_t (not always an int) */
 420   vtype_uid,            /* value is address of uid_t (not always an int) */
 421   vtype_gid,            /* value is address of gid_t (not always an int) */
 422   vtype_bool,           /* value is address of bool */
 423   vtype_stringptr,      /* value is address of pointer to string */
 424   vtype_msgbody,        /* as stringptr, but read when first required */
 425   vtype_msgbody_end,    /* ditto, the end of the message */
 426   vtype_msgheaders,     /* the message's headers, processed */
 427   vtype_msgheaders_raw, /* the message's headers, unprocessed */
 428   vtype_localpart,      /* extract local part from string */
 429   vtype_domain,         /* extract domain from string */
 430   vtype_string_func,    /* value is string returned by given function */
 431   vtype_todbsdin,       /* value not used; generate BSD inbox tod */
 432   vtype_tode,           /* value not used; generate tod in epoch format */
 433   vtype_todel,          /* value not used; generate tod in epoch/usec format */
 434   vtype_todf,           /* value not used; generate full tod */
 435   vtype_todl,           /* value not used; generate log tod */
 436   vtype_todlf,          /* value not used; generate log file datestamp tod */
 437   vtype_todzone,        /* value not used; generate time zone only */
 438   vtype_todzulu,        /* value not used; generate zulu tod */
 439   vtype_reply,          /* value not used; get reply from headers */
 440   vtype_pid,            /* value not used; result is pid */
 441   vtype_host_lookup,    /* value not used; get host name */
 442   vtype_load_avg,       /* value not used; result is int from os_getloadavg */
 443   vtype_pspace,         /* partition space; value is T/F for spool/log */
 444   vtype_pinodes,        /* partition inodes; value is T/F for spool/log */
 445   vtype_cert            /* SSL certificate */
 446   #ifndef DISABLE_DKIM
 447   ,vtype_dkim           /* Lookup of value in DKIM signature */
 448   #endif
 449 };
 450
 451 /* Type for main variable table */
 452
 453 typedef struct {
 454   const char *name;
 455   enum vtypes type;
 456   void       *value;
 457 } var_entry;
 458
 459 /* Type for entries pointing to address/length pairs. Not currently
 460 in use. */
 461
 462 typedef struct {
 463   uschar **address;
 464   int  *length;
 465 } alblock;
 466
 467 static uschar * fn_recipients(void);
 468 typedef uschar * stringptr_fn_t(void);
 469 static uschar * fn_queue_size(void);
 470
 471 /* This table must be kept in alphabetical order. */
 472
 473 static var_entry var_table[] = {
 474   /* WARNING: Do not invent variables whose names start acl_c or acl_m because
 475      they will be confused with user-creatable ACL variables. */
 476   { "acl_arg1",            vtype_stringptr,   &acl_arg[0] },
 477   { "acl_arg2",            vtype_stringptr,   &acl_arg[1] },
 478   { "acl_arg3",            vtype_stringptr,   &acl_arg[2] },
 479   { "acl_arg4",            vtype_stringptr,   &acl_arg[3] },
 480   { "acl_arg5",            vtype_stringptr,   &acl_arg[4] },
 481   { "acl_arg6",            vtype_stringptr,   &acl_arg[5] },
 482   { "acl_arg7",            vtype_stringptr,   &acl_arg[6] },
 483   { "acl_arg8",            vtype_stringptr,   &acl_arg[7] },
 484   { "acl_arg9",            vtype_stringptr,   &acl_arg[8] },
 485   { "acl_narg",            vtype_int,         &acl_narg },
 486   { "acl_verify_message",  vtype_stringptr,   &acl_verify_message },
 487   { "address_data",        vtype_stringptr,   &deliver_address_data },
 488   { "address_file",        vtype_stringptr,   &address_file },
 489   { "address_pipe",        vtype_stringptr,   &address_pipe },
 490 #ifdef EXPERIMENTAL_ARC
 491   { "arc_domains",         vtype_string_func, (void *) &fn_arc_domains },
 492   { "arc_oldest_pass",     vtype_int,         &arc_oldest_pass },
 493   { "arc_state",           vtype_stringptr,   &arc_state },
 494   { "arc_state_reason",    vtype_stringptr,   &arc_state_reason },
 495 #endif
 496   { "authenticated_fail_id",vtype_stringptr,  &authenticated_fail_id },
 497   { "authenticated_id",    vtype_stringptr,   &authenticated_id },
 498   { "authenticated_sender",vtype_stringptr,   &authenticated_sender },
 499   { "authentication_failed",vtype_int,        &authentication_failed },
 500 #ifdef WITH_CONTENT_SCAN
 501   { "av_failed",           vtype_int,         &av_failed },
 502 #endif
 503 #ifdef EXPERIMENTAL_BRIGHTMAIL
 504   { "bmi_alt_location",    vtype_stringptr,   &bmi_alt_location },
 505   { "bmi_base64_tracker_verdict", vtype_stringptr, &bmi_base64_tracker_verdict },
 506   { "bmi_base64_verdict",  vtype_stringptr,   &bmi_base64_verdict },
 507   { "bmi_deliver",         vtype_int,         &bmi_deliver },
 508 #endif
 509   { "body_linecount",      vtype_int,         &body_linecount },
 510   { "body_zerocount",      vtype_int,         &body_zerocount },
 511   { "bounce_recipient",    vtype_stringptr,   &bounce_recipient },
 512   { "bounce_return_size_limit", vtype_int,    &bounce_return_size_limit },
 513   { "caller_gid",          vtype_gid,         &real_gid },
 514   { "caller_uid",          vtype_uid,         &real_uid },
 515   { "callout_address",     vtype_stringptr,   &callout_address },
 516   { "compile_date",        vtype_stringptr,   &version_date },
 517   { "compile_number",      vtype_stringptr,   &version_cnumber },
 518   { "config_dir",          vtype_stringptr,   &config_main_directory },
 519   { "config_file",         vtype_stringptr,   &config_main_filename },
 520   { "csa_status",          vtype_stringptr,   &csa_status },
 521 #ifdef EXPERIMENTAL_DCC
 522   { "dcc_header",          vtype_stringptr,   &dcc_header },
 523   { "dcc_result",          vtype_stringptr,   &dcc_result },
 524 #endif
 525 #ifndef DISABLE_DKIM
 526   { "dkim_algo",           vtype_dkim,        (void *)DKIM_ALGO },
 527   { "dkim_bodylength",     vtype_dkim,        (void *)DKIM_BODYLENGTH },
 528   { "dkim_canon_body",     vtype_dkim,        (void *)DKIM_CANON_BODY },
 529   { "dkim_canon_headers",  vtype_dkim,        (void *)DKIM_CANON_HEADERS },
 530   { "dkim_copiedheaders",  vtype_dkim,        (void *)DKIM_COPIEDHEADERS },
 531   { "dkim_created",        vtype_dkim,        (void *)DKIM_CREATED },
 532   { "dkim_cur_signer",     vtype_stringptr,   &dkim_cur_signer },
 533   { "dkim_domain",         vtype_stringptr,   &dkim_signing_domain },
 534   { "dkim_expires",        vtype_dkim,        (void *)DKIM_EXPIRES },
 535   { "dkim_headernames",    vtype_dkim,        (void *)DKIM_HEADERNAMES },
 536   { "dkim_identity",       vtype_dkim,        (void *)DKIM_IDENTITY },
 537   { "dkim_key_granularity",vtype_dkim,        (void *)DKIM_KEY_GRANULARITY },
 538   { "dkim_key_length",     vtype_int,         &dkim_key_length },
 539   { "dkim_key_nosubdomains",vtype_dkim,       (void *)DKIM_NOSUBDOMAINS },
 540   { "dkim_key_notes",      vtype_dkim,        (void *)DKIM_KEY_NOTES },
 541   { "dkim_key_srvtype",    vtype_dkim,        (void *)DKIM_KEY_SRVTYPE },
 542   { "dkim_key_testing",    vtype_dkim,        (void *)DKIM_KEY_TESTING },
 543   { "dkim_selector",       vtype_stringptr,   &dkim_signing_selector },
 544   { "dkim_signers",        vtype_stringptr,   &dkim_signers },
 545   { "dkim_verify_reason",  vtype_stringptr,   &dkim_verify_reason },
 546   { "dkim_verify_status",  vtype_stringptr,   &dkim_verify_status },
 547 #endif
 548 #ifdef SUPPORT_DMARC
 549   { "dmarc_domain_policy", vtype_stringptr,   &dmarc_domain_policy },
 550   { "dmarc_status",        vtype_stringptr,   &dmarc_status },
 551   { "dmarc_status_text",   vtype_stringptr,   &dmarc_status_text },
 552   { "dmarc_used_domain",   vtype_stringptr,   &dmarc_used_domain },
 553 #endif
 554   { "dnslist_domain",      vtype_stringptr,   &dnslist_domain },
 555   { "dnslist_matched",     vtype_stringptr,   &dnslist_matched },
 556   { "dnslist_text",        vtype_stringptr,   &dnslist_text },
 557   { "dnslist_value",       vtype_stringptr,   &dnslist_value },
 558   { "domain",              vtype_stringptr,   &deliver_domain },
 559   { "domain_data",         vtype_stringptr,   &deliver_domain_data },
 560 #ifndef DISABLE_EVENT
 561   { "event_data",          vtype_stringptr,   &event_data },
 562
 563   /*XXX want to use generic vars for as many of these as possible*/
 564   { "event_defer_errno",   vtype_int,         &event_defer_errno },
 565
 566   { "event_name",          vtype_stringptr,   &event_name },
 567 #endif
 568   { "exim_gid",            vtype_gid,         &exim_gid },
 569   { "exim_path",           vtype_stringptr,   &exim_path },
 570   { "exim_uid",            vtype_uid,         &exim_uid },
 571   { "exim_version",        vtype_stringptr,   &version_string },
 572   { "headers_added",       vtype_string_func, (void *) &fn_hdrs_added },
 573   { "home",                vtype_stringptr,   &deliver_home },
 574   { "host",                vtype_stringptr,   &deliver_host },
 575   { "host_address",        vtype_stringptr,   &deliver_host_address },
 576   { "host_data",           vtype_stringptr,   &host_data },
 577   { "host_lookup_deferred",vtype_int,         &host_lookup_deferred },
 578   { "host_lookup_failed",  vtype_int,         &host_lookup_failed },
 579   { "host_port",           vtype_int,         &deliver_host_port },
 580   { "initial_cwd",         vtype_stringptr,   &initial_cwd },
 581   { "inode",               vtype_ino,         &deliver_inode },
 582   { "interface_address",   vtype_stringptr,   &interface_address },
 583   { "interface_port",      vtype_int,         &interface_port },
 584   { "item",                vtype_stringptr,   &iterate_item },
 585   #ifdef LOOKUP_LDAP
 586   { "ldap_dn",             vtype_stringptr,   &eldap_dn },
 587   #endif
 588   { "load_average",        vtype_load_avg,    NULL },
 589   { "local_part",          vtype_stringptr,   &deliver_localpart },
 590   { "local_part_data",     vtype_stringptr,   &deliver_localpart_data },
 591   { "local_part_prefix",   vtype_stringptr,   &deliver_localpart_prefix },
 592   { "local_part_prefix_v", vtype_stringptr,   &deliver_localpart_prefix_v },
 593   { "local_part_suffix",   vtype_stringptr,   &deliver_localpart_suffix },
 594   { "local_part_suffix_v", vtype_stringptr,   &deliver_localpart_suffix_v },
 595   { "local_part_verified", vtype_stringptr,   &deliver_localpart_verified },
 596 #ifdef HAVE_LOCAL_SCAN
 597   { "local_scan_data",     vtype_stringptr,   &local_scan_data },
 598 #endif
 599   { "local_user_gid",      vtype_gid,         &local_user_gid },
 600   { "local_user_uid",      vtype_uid,         &local_user_uid },
 601   { "localhost_number",    vtype_int,         &host_number },
 602   { "log_inodes",          vtype_pinodes,     (void *)FALSE },
 603   { "log_space",           vtype_pspace,      (void *)FALSE },
 604   { "lookup_dnssec_authenticated",vtype_stringptr,&lookup_dnssec_authenticated},
 605   { "mailstore_basename",  vtype_stringptr,   &mailstore_basename },
 606 #ifdef WITH_CONTENT_SCAN
 607   { "malware_name",        vtype_stringptr,   &malware_name },
 608 #endif
 609   { "max_received_linelength", vtype_int,     &max_received_linelength },
 610   { "message_age",         vtype_int,         &message_age },
 611   { "message_body",        vtype_msgbody,     &message_body },
 612   { "message_body_end",    vtype_msgbody_end, &message_body_end },
 613   { "message_body_size",   vtype_int,         &message_body_size },
 614   { "message_exim_id",     vtype_stringptr,   &message_id },
 615   { "message_headers",     vtype_msgheaders,  NULL },
 616   { "message_headers_raw", vtype_msgheaders_raw, NULL },
 617   { "message_id",          vtype_stringptr,   &message_id },
 618   { "message_linecount",   vtype_int,         &message_linecount },
 619   { "message_size",        vtype_int,         &message_size },
 620 #ifdef SUPPORT_I18N
 621   { "message_smtputf8",    vtype_bool,        &message_smtputf8 },
 622 #endif
 623 #ifdef WITH_CONTENT_SCAN
 624   { "mime_anomaly_level",  vtype_int,         &mime_anomaly_level },
 625   { "mime_anomaly_text",   vtype_stringptr,   &mime_anomaly_text },
 626   { "mime_boundary",       vtype_stringptr,   &mime_boundary },
 627   { "mime_charset",        vtype_stringptr,   &mime_charset },
 628   { "mime_content_description", vtype_stringptr, &mime_content_description },
 629   { "mime_content_disposition", vtype_stringptr, &mime_content_disposition },
 630   { "mime_content_id",     vtype_stringptr,   &mime_content_id },
 631   { "mime_content_size",   vtype_int,         &mime_content_size },
 632   { "mime_content_transfer_encoding",vtype_stringptr, &mime_content_transfer_encoding },
 633   { "mime_content_type",   vtype_stringptr,   &mime_content_type },
 634   { "mime_decoded_filename", vtype_stringptr, &mime_decoded_filename },
 635   { "mime_filename",       vtype_stringptr,   &mime_filename },
 636   { "mime_is_coverletter", vtype_int,         &mime_is_coverletter },
 637   { "mime_is_multipart",   vtype_int,         &mime_is_multipart },
 638   { "mime_is_rfc822",      vtype_int,         &mime_is_rfc822 },
 639   { "mime_part_count",     vtype_int,         &mime_part_count },
 640 #endif
 641   { "n0",                  vtype_filter_int,  &filter_n[0] },
 642   { "n1",                  vtype_filter_int,  &filter_n[1] },
 643   { "n2",                  vtype_filter_int,  &filter_n[2] },
 644   { "n3",                  vtype_filter_int,  &filter_n[3] },
 645   { "n4",                  vtype_filter_int,  &filter_n[4] },
 646   { "n5",                  vtype_filter_int,  &filter_n[5] },
 647   { "n6",                  vtype_filter_int,  &filter_n[6] },
 648   { "n7",                  vtype_filter_int,  &filter_n[7] },
 649   { "n8",                  vtype_filter_int,  &filter_n[8] },
 650   { "n9",                  vtype_filter_int,  &filter_n[9] },
 651   { "original_domain",     vtype_stringptr,   &deliver_domain_orig },
 652   { "original_local_part", vtype_stringptr,   &deliver_localpart_orig },
 653   { "originator_gid",      vtype_gid,         &originator_gid },
 654   { "originator_uid",      vtype_uid,         &originator_uid },
 655   { "parent_domain",       vtype_stringptr,   &deliver_domain_parent },
 656   { "parent_local_part",   vtype_stringptr,   &deliver_localpart_parent },
 657   { "pid",                 vtype_pid,         NULL },
 658 #ifndef DISABLE_PRDR
 659   { "prdr_requested",      vtype_bool,        &prdr_requested },
 660 #endif
 661   { "primary_hostname",    vtype_stringptr,   &primary_hostname },
 662 #if defined(SUPPORT_PROXY) || defined(SUPPORT_SOCKS)
 663   { "proxy_external_address",vtype_stringptr, &proxy_external_address },
 664   { "proxy_external_port", vtype_int,         &proxy_external_port },
 665   { "proxy_local_address", vtype_stringptr,   &proxy_local_address },
 666   { "proxy_local_port",    vtype_int,         &proxy_local_port },
 667   { "proxy_session",       vtype_bool,        &proxy_session },
 668 #endif
 669   { "prvscheck_address",   vtype_stringptr,   &prvscheck_address },
 670   { "prvscheck_keynum",    vtype_stringptr,   &prvscheck_keynum },
 671   { "prvscheck_result",    vtype_stringptr,   &prvscheck_result },
 672   { "qualify_domain",      vtype_stringptr,   &qualify_domain_sender },
 673   { "qualify_recipient",   vtype_stringptr,   &qualify_domain_recipient },
 674   { "queue_name",          vtype_stringptr,   &queue_name },
 675   { "queue_size",          vtype_string_func, &fn_queue_size },
 676   { "rcpt_count",          vtype_int,         &rcpt_count },
 677   { "rcpt_defer_count",    vtype_int,         &rcpt_defer_count },
 678   { "rcpt_fail_count",     vtype_int,         &rcpt_fail_count },
 679   { "received_count",      vtype_int,         &received_count },
 680   { "received_for",        vtype_stringptr,   &received_for },
 681   { "received_ip_address", vtype_stringptr,   &interface_address },
 682   { "received_port",       vtype_int,         &interface_port },
 683   { "received_protocol",   vtype_stringptr,   &received_protocol },
 684   { "received_time",       vtype_int,         &received_time.tv_sec },
 685   { "recipient_data",      vtype_stringptr,   &recipient_data },
 686   { "recipient_verify_failure",vtype_stringptr,&recipient_verify_failure },
 687   { "recipients",          vtype_string_func, (void *) &fn_recipients },
 688   { "recipients_count",    vtype_int,         &recipients_count },
 689 #ifdef WITH_CONTENT_SCAN
 690   { "regex_match_string",  vtype_stringptr,   &regex_match_string },
 691 #endif
 692   { "reply_address",       vtype_reply,       NULL },
 693   { "return_path",         vtype_stringptr,   &return_path },
 694   { "return_size_limit",   vtype_int,         &bounce_return_size_limit },
 695   { "router_name",         vtype_stringptr,   &router_name },
 696   { "runrc",               vtype_int,         &runrc },
 697   { "self_hostname",       vtype_stringptr,   &self_hostname },
 698   { "sender_address",      vtype_stringptr,   &sender_address },
 699   { "sender_address_data", vtype_stringptr,   &sender_address_data },
 700   { "sender_address_domain", vtype_domain,    &sender_address },
 701   { "sender_address_local_part", vtype_localpart, &sender_address },
 702   { "sender_data",         vtype_stringptr,   &sender_data },
 703   { "sender_fullhost",     vtype_stringptr,   &sender_fullhost },
 704   { "sender_helo_dnssec",  vtype_bool,        &sender_helo_dnssec },
 705   { "sender_helo_name",    vtype_stringptr,   &sender_helo_name },
 706   { "sender_host_address", vtype_stringptr,   &sender_host_address },
 707   { "sender_host_authenticated",vtype_stringptr, &sender_host_authenticated },
 708   { "sender_host_dnssec",  vtype_bool,        &sender_host_dnssec },
 709   { "sender_host_name",    vtype_host_lookup, NULL },
 710   { "sender_host_port",    vtype_int,         &sender_host_port },
 711   { "sender_ident",        vtype_stringptr,   &sender_ident },
 712   { "sender_rate",         vtype_stringptr,   &sender_rate },
 713   { "sender_rate_limit",   vtype_stringptr,   &sender_rate_limit },
 714   { "sender_rate_period",  vtype_stringptr,   &sender_rate_period },
 715   { "sender_rcvhost",      vtype_stringptr,   &sender_rcvhost },
 716   { "sender_verify_failure",vtype_stringptr,  &sender_verify_failure },
 717   { "sending_ip_address",  vtype_stringptr,   &sending_ip_address },
 718   { "sending_port",        vtype_int,         &sending_port },
 719   { "smtp_active_hostname", vtype_stringptr,  &smtp_active_hostname },
 720   { "smtp_command",        vtype_stringptr,   &smtp_cmd_buffer },
 721   { "smtp_command_argument", vtype_stringptr, &smtp_cmd_argument },
 722   { "smtp_command_history", vtype_string_func, (void *) &smtp_cmd_hist },
 723   { "smtp_count_at_connection_start", vtype_int, &smtp_accept_count },
 724   { "smtp_notquit_reason", vtype_stringptr,   &smtp_notquit_reason },
 725   { "sn0",                 vtype_filter_int,  &filter_sn[0] },
 726   { "sn1",                 vtype_filter_int,  &filter_sn[1] },
 727   { "sn2",                 vtype_filter_int,  &filter_sn[2] },
 728   { "sn3",                 vtype_filter_int,  &filter_sn[3] },
 729   { "sn4",                 vtype_filter_int,  &filter_sn[4] },
 730   { "sn5",                 vtype_filter_int,  &filter_sn[5] },
 731   { "sn6",                 vtype_filter_int,  &filter_sn[6] },
 732   { "sn7",                 vtype_filter_int,  &filter_sn[7] },
 733   { "sn8",                 vtype_filter_int,  &filter_sn[8] },
 734   { "sn9",                 vtype_filter_int,  &filter_sn[9] },
 735 #ifdef WITH_CONTENT_SCAN
 736   { "spam_action",         vtype_stringptr,   &spam_action },
 737   { "spam_bar",            vtype_stringptr,   &spam_bar },
 738   { "spam_report",         vtype_stringptr,   &spam_report },
 739   { "spam_score",          vtype_stringptr,   &spam_score },
 740   { "spam_score_int",      vtype_stringptr,   &spam_score_int },
 741 #endif
 742 #ifdef SUPPORT_SPF
 743   { "spf_guess",           vtype_stringptr,   &spf_guess },
 744   { "spf_header_comment",  vtype_stringptr,   &spf_header_comment },
 745   { "spf_received",        vtype_stringptr,   &spf_received },
 746   { "spf_result",          vtype_stringptr,   &spf_result },
 747   { "spf_result_guessed",  vtype_bool,        &spf_result_guessed },
 748   { "spf_smtp_comment",    vtype_stringptr,   &spf_smtp_comment },
 749 #endif
 750   { "spool_directory",     vtype_stringptr,   &spool_directory },
 751   { "spool_inodes",        vtype_pinodes,     (void *)TRUE },
 752   { "spool_space",         vtype_pspace,      (void *)TRUE },
 753 #ifdef EXPERIMENTAL_SRS
 754   { "srs_db_address",      vtype_stringptr,   &srs_db_address },
 755   { "srs_db_key",          vtype_stringptr,   &srs_db_key },
 756   { "srs_orig_recipient",  vtype_stringptr,   &srs_orig_recipient },
 757   { "srs_orig_sender",     vtype_stringptr,   &srs_orig_sender },
 758 #endif
 759 #if defined(EXPERIMENTAL_SRS) || defined(EXPERIMENTAL_SRS_NATIVE)
 760   { "srs_recipient",       vtype_stringptr,   &srs_recipient },
 761 #endif
 762 #ifdef EXPERIMENTAL_SRS
 763   { "srs_status",          vtype_stringptr,   &srs_status },
 764 #endif
 765   { "thisaddress",         vtype_stringptr,   &filter_thisaddress },
 766
 767   /* The non-(in,out) variables are now deprecated */
 768   { "tls_bits",            vtype_int,         &tls_in.bits },
 769   { "tls_certificate_verified", vtype_int,    &tls_in.certificate_verified },
 770   { "tls_cipher",          vtype_stringptr,   &tls_in.cipher },
 771
 772   { "tls_in_bits",         vtype_int,         &tls_in.bits },
 773   { "tls_in_certificate_verified", vtype_int, &tls_in.certificate_verified },
 774   { "tls_in_cipher",       vtype_stringptr,   &tls_in.cipher },
 775   { "tls_in_cipher_std",   vtype_stringptr,   &tls_in.cipher_stdname },
 776   { "tls_in_ocsp",         vtype_int,         &tls_in.ocsp },
 777   { "tls_in_ourcert",      vtype_cert,        &tls_in.ourcert },
 778   { "tls_in_peercert",     vtype_cert,        &tls_in.peercert },
 779   { "tls_in_peerdn",       vtype_stringptr,   &tls_in.peerdn },
 780 #ifdef EXPERIMENTAL_TLS_RESUME
 781   { "tls_in_resumption",   vtype_int,         &tls_in.resumption },
 782 #endif
 783 #ifndef DISABLE_TLS
 784   { "tls_in_sni",          vtype_stringptr,   &tls_in.sni },
 785 #endif
 786   { "tls_in_ver",          vtype_stringptr,   &tls_in.ver },
 787   { "tls_out_bits",        vtype_int,         &tls_out.bits },
 788   { "tls_out_certificate_verified", vtype_int,&tls_out.certificate_verified },
 789   { "tls_out_cipher",      vtype_stringptr,   &tls_out.cipher },
 790   { "tls_out_cipher_std",  vtype_stringptr,   &tls_out.cipher_stdname },
 791 #ifdef SUPPORT_DANE
 792   { "tls_out_dane",        vtype_bool,        &tls_out.dane_verified },
 793 #endif
 794   { "tls_out_ocsp",        vtype_int,         &tls_out.ocsp },
 795   { "tls_out_ourcert",     vtype_cert,        &tls_out.ourcert },
 796   { "tls_out_peercert",    vtype_cert,        &tls_out.peercert },
 797   { "tls_out_peerdn",      vtype_stringptr,   &tls_out.peerdn },
 798 #ifdef EXPERIMENTAL_TLS_RESUME
 799   { "tls_out_resumption",  vtype_int,         &tls_out.resumption },
 800 #endif
 801 #ifndef DISABLE_TLS
 802   { "tls_out_sni",         vtype_stringptr,   &tls_out.sni },
 803 #endif
 804 #ifdef SUPPORT_DANE
 805   { "tls_out_tlsa_usage",  vtype_int,         &tls_out.tlsa_usage },
 806 #endif
 807   { "tls_out_ver",         vtype_stringptr,   &tls_out.ver },
 808
 809   { "tls_peerdn",          vtype_stringptr,   &tls_in.peerdn }, /* mind the alphabetical order! */
 810 #ifndef DISABLE_TLS
 811   { "tls_sni",             vtype_stringptr,   &tls_in.sni },    /* mind the alphabetical order! */
 812 #endif
 813
 814   { "tod_bsdinbox",        vtype_todbsdin,    NULL },
 815   { "tod_epoch",           vtype_tode,        NULL },
 816   { "tod_epoch_l",         vtype_todel,       NULL },
 817   { "tod_full",            vtype_todf,        NULL },
 818   { "tod_log",             vtype_todl,        NULL },
 819   { "tod_logfile",         vtype_todlf,       NULL },
 820   { "tod_zone",            vtype_todzone,     NULL },
 821   { "tod_zulu",            vtype_todzulu,     NULL },
 822   { "transport_name",      vtype_stringptr,   &transport_name },
 823   { "value",               vtype_stringptr,   &lookup_value },
 824   { "verify_mode",         vtype_stringptr,   &verify_mode },
 825   { "version_number",      vtype_stringptr,   &version_string },
 826   { "warn_message_delay",  vtype_stringptr,   &warnmsg_delay },
 827   { "warn_message_recipient",vtype_stringptr, &warnmsg_recipients },
 828   { "warn_message_recipients",vtype_stringptr,&warnmsg_recipients },
 829   { "warnmsg_delay",       vtype_stringptr,   &warnmsg_delay },
 830   { "warnmsg_recipient",   vtype_stringptr,   &warnmsg_recipients },
 831   { "warnmsg_recipients",  vtype_stringptr,   &warnmsg_recipients }
 832 };
 833
 834 static int var_table_size = nelem(var_table);
 835 static uschar var_buffer[256];
 836 static BOOL malformed_header;
 837
 838 /* For textual hashes */
 839
 840 static const char *hashcodes = "abcdefghijklmnopqrtsuvwxyz"
 841                                "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
 842                                "0123456789";
 843
 844 enum { HMAC_MD5, HMAC_SHA1 };
 845
 846 /* For numeric hashes */
 847
 848 static unsigned int prime[] = {
 849   2,   3,   5,   7,  11,  13,  17,  19,  23,  29,
 850  31,  37,  41,  43,  47,  53,  59,  61,  67,  71,
 851  73,  79,  83,  89,  97, 101, 103, 107, 109, 113};
 852
 853 /* For printing modes in symbolic form */
 854
 855 static uschar *mtable_normal[] =
 856   { US"---", US"--x", US"-w-", US"-wx", US"r--", US"r-x", US"rw-", US"rwx" };
 857
 858 static uschar *mtable_setid[] =
 859   { US"--S", US"--s", US"-wS", US"-ws", US"r-S", US"r-s", US"rwS", US"rws" };
 860
 861 static uschar *mtable_sticky[] =
 862   { US"--T", US"--t", US"-wT", US"-wt", US"r-T", US"r-t", US"rwT", US"rwt" };
 863
 864 /* flags for find_header() */
 865 #define FH_EXISTS_ONLY  BIT(0)
 866 #define FH_WANT_RAW     BIT(1)
 867 #define FH_WANT_LIST    BIT(2)
 868
 869
 870 /*************************************************
 871 *           Tables for UTF-8 support             *
 872 *************************************************/
 873
 874 /* Table of the number of extra characters, indexed by the first character
 875 masked with 0x3f. The highest number for a valid UTF-8 character is in fact
 876 0x3d. */
 877
 878 static uschar utf8_table1[] = {
 879   1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
 880   1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
 881   2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
 882   3,3,3,3,3,3,3,3,4,4,4,4,5,5,5,5 };
 883
 884 /* These are the masks for the data bits in the first byte of a character,
 885 indexed by the number of additional bytes. */
 886
 887 static int utf8_table2[] = { 0xff, 0x1f, 0x0f, 0x07, 0x03, 0x01};
 888
 889 /* Get the next UTF-8 character, advancing the pointer. */
 890
 891 #define GETUTF8INC(c, ptr) \
 892   c = *ptr++; \
 893   if ((c & 0xc0) == 0xc0) \
 894     { \
 895     int a = utf8_table1[c & 0x3f];  /* Number of additional bytes */ \
 896     int s = 6*a; \
 897     c = (c & utf8_table2[a]) << s; \
 898     while (a-- > 0) \
 899       { \
 900       s -= 6; \
 901       c |= (*ptr++ & 0x3f) << s; \
 902       } \
 903     }
 904
 905
 906
 907 static uschar * base32_chars = US"abcdefghijklmnopqrstuvwxyz234567";
 908
 909 /*************************************************
 910 *           Binary chop search on a table        *
 911 *************************************************/
 912
 913 /* This is used for matching expansion items and operators.
 914
 915 Arguments:
 916   name        the name that is being sought
 917   table       the table to search
 918   table_size  the number of items in the table
 919
 920 Returns:      the offset in the table, or -1
 921 */
 922
 923 static int
 924 chop_match(uschar *name, uschar **table, int table_size)
 925 {
 926 uschar **bot = table;
 927 uschar **top = table + table_size;
 928
 929 while (top > bot)
 930   {
 931   uschar **mid = bot + (top - bot)/2;
 932   int c = Ustrcmp(name, *mid);
 933   if (c == 0) return mid - table;
 934   if (c > 0) bot = mid + 1; else top = mid;
 935   }
 936
 937 return -1;
 938 }
 939
 940
 941
 942 /*************************************************
 943 *          Check a condition string              *
 944 *************************************************/
 945
 946 /* This function is called to expand a string, and test the result for a "true"
 947 or "false" value. Failure of the expansion yields FALSE; logged unless it was a
 948 forced fail or lookup defer.
 949
 950 We used to release all store used, but this is not not safe due
 951 to ${dlfunc } and ${acl }.  In any case expand_string_internal()
 952 is reasonably careful to release what it can.
 953
 954 The actual false-value tests should be replicated for ECOND_BOOL_LAX.
 955
 956 Arguments:
 957   condition     the condition string
 958   m1            text to be incorporated in panic error
 959   m2            ditto
 960
 961 Returns:        TRUE if condition is met, FALSE if not
 962 */
 963
 964 BOOL
 965 expand_check_condition(uschar *condition, uschar *m1, uschar *m2)
 966 {
 967 uschar * ss = expand_string(condition);
 968 if (!ss)
 969   {
 970   if (!f.expand_string_forcedfail && !f.search_find_defer)
 971     log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand condition \"%s\" "
 972       "for %s %s: %s", condition, m1, m2, expand_string_message);
 973   return FALSE;
 974   }
 975 return *ss && Ustrcmp(ss, "0") != 0 && strcmpic(ss, US"no") != 0 &&
 976   strcmpic(ss, US"false") != 0;
 977 }
 978
 979
 980
 981
 982 /*************************************************
 983 *        Pseudo-random number generation         *
 984 *************************************************/
 985
 986 /* Pseudo-random number generation.  The result is not "expected" to be
 987 cryptographically strong but not so weak that someone will shoot themselves
 988 in the foot using it as a nonce in some email header scheme or whatever
 989 weirdness they'll twist this into.  The result should ideally handle fork().
 990
 991 However, if we're stuck unable to provide this, then we'll fall back to
 992 appallingly bad randomness.
 993
 994 If DISABLE_TLS is not defined then this will not be used except as an emergency
 995 fallback.
 996
 997 Arguments:
 998   max       range maximum
 999 Returns     a random number in range [0, max-1]
1000 */
1001
1002 #ifndef DISABLE_TLS
1003 # define vaguely_random_number vaguely_random_number_fallback
1004 #endif
1005 int
1006 vaguely_random_number(int max)
1007 {
1008 #ifndef DISABLE_TLS
1009 # undef vaguely_random_number
1010 #endif
1011 static pid_t pid = 0;
1012 pid_t p2;
1013
1014 if ((p2 = getpid()) != pid)
1015   {
1016   if (pid != 0)
1017     {
1018
1019 #ifdef HAVE_ARC4RANDOM
1020     /* cryptographically strong randomness, common on *BSD platforms, not
1021     so much elsewhere.  Alas. */
1022 # ifndef NOT_HAVE_ARC4RANDOM_STIR
1023     arc4random_stir();
1024 # endif
1025 #elif defined(HAVE_SRANDOM) || defined(HAVE_SRANDOMDEV)
1026 # ifdef HAVE_SRANDOMDEV
1027     /* uses random(4) for seeding */
1028     srandomdev();
1029 # else
1030     {
1031     struct timeval tv;
1032     gettimeofday(&tv, NULL);
1033     srandom(tv.tv_sec | tv.tv_usec | getpid());
1034     }
1035 # endif
1036 #else
1037     /* Poor randomness and no seeding here */
1038 #endif
1039
1040     }
1041   pid = p2;
1042   }
1043
1044 #ifdef HAVE_ARC4RANDOM
1045 return arc4random() % max;
1046 #elif defined(HAVE_SRANDOM) || defined(HAVE_SRANDOMDEV)
1047 return random() % max;
1048 #else
1049 /* This one returns a 16-bit number, definitely not crypto-strong */
1050 return random_number(max);
1051 #endif
1052 }
1053
1054
1055
1056
1057 /*************************************************
1058 *             Pick out a name from a string      *
1059 *************************************************/
1060
1061 /* If the name is too long, it is silently truncated.
1062
1063 Arguments:
1064   name      points to a buffer into which to put the name
1065   max       is the length of the buffer
1066   s         points to the first alphabetic character of the name
1067   extras    chars other than alphanumerics to permit
1068
1069 Returns:    pointer to the first character after the name
1070
1071 Note: The test for *s != 0 in the while loop is necessary because
1072 Ustrchr() yields non-NULL if the character is zero (which is not something
1073 I expected). */
1074
1075 static const uschar *
1076 read_name(uschar *name, int max, const uschar *s, uschar *extras)
1077 {
1078 int ptr = 0;
1079 while (*s && (isalnum(*s) || Ustrchr(extras, *s) != NULL))
1080   {
1081   if (ptr < max-1) name[ptr++] = *s;
1082   s++;
1083   }
1084 name[ptr] = 0;
1085 return s;
1086 }
1087
1088
1089
1090 /*************************************************
1091 *     Pick out the rest of a header name         *
1092 *************************************************/
1093
1094 /* A variable name starting $header_ (or just $h_ for those who like
1095 abbreviations) might not be the complete header name because headers can
1096 contain any printing characters in their names, except ':'. This function is
1097 called to read the rest of the name, chop h[eader]_ off the front, and put ':'
1098 on the end, if the name was terminated by white space.
1099
1100 Arguments:
1101   name      points to a buffer in which the name read so far exists
1102   max       is the length of the buffer
1103   s         points to the first character after the name so far, i.e. the
1104             first non-alphameric character after $header_xxxxx
1105
1106 Returns:    a pointer to the first character after the header name
1107 */
1108
1109 static const uschar *
1110 read_header_name(uschar *name, int max, const uschar *s)
1111 {
1112 int prelen = Ustrchr(name, '_') - name + 1;
1113 int ptr = Ustrlen(name) - prelen;
1114 if (ptr > 0) memmove(name, name+prelen, ptr);
1115 while (mac_isgraph(*s) && *s != ':')
1116   {
1117   if (ptr < max-1) name[ptr++] = *s;
1118   s++;
1119   }
1120 if (*s == ':') s++;
1121 name[ptr++] = ':';
1122 name[ptr] = 0;
1123 return s;
1124 }
1125
1126
1127
1128 /*************************************************
1129 *           Pick out a number from a string      *
1130 *************************************************/
1131
1132 /* Arguments:
1133   n     points to an integer into which to put the number
1134   s     points to the first digit of the number
1135
1136 Returns:  a pointer to the character after the last digit
1137 */
1138 /*XXX consider expanding to int_eximarith_t.  But the test for
1139 "overbig numbers" in 0002 still needs to overflow it. */
1140
1141 static uschar *
1142 read_number(int *n, uschar *s)
1143 {
1144 *n = 0;
1145 while (isdigit(*s)) *n = *n * 10 + (*s++ - '0');
1146 return s;
1147 }
1148
1149 static const uschar *
1150 read_cnumber(int *n, const uschar *s)
1151 {
1152 *n = 0;
1153 while (isdigit(*s)) *n = *n * 10 + (*s++ - '0');
1154 return s;
1155 }
1156
1157
1158
1159 /*************************************************
1160 *        Extract keyed subfield from a string    *
1161 *************************************************/
1162
1163 /* The yield is in dynamic store; NULL means that the key was not found.
1164
1165 Arguments:
1166   key       points to the name of the key
1167   s         points to the string from which to extract the subfield
1168
1169 Returns:    NULL if the subfield was not found, or
1170             a pointer to the subfield's data
1171 */
1172
1173 static uschar *
1174 expand_getkeyed(uschar * key, const uschar * s)
1175 {
1176 int length = Ustrlen(key);
1177 while (isspace(*s)) s++;
1178
1179 /* Loop to search for the key */
1180
1181 while (*s)
1182   {
1183   int dkeylength;
1184   uschar * data;
1185   const uschar * dkey = s;
1186
1187   while (*s && *s != '=' && !isspace(*s)) s++;
1188   dkeylength = s - dkey;
1189   while (isspace(*s)) s++;
1190   if (*s == '=') while (isspace((*(++s))));
1191
1192   data = string_dequote(&s);
1193   if (length == dkeylength && strncmpic(key, dkey, length) == 0)
1194     return data;
1195
1196   while (isspace(*s)) s++;
1197   }
1198
1199 return NULL;
1200 }
1201
1202
1203
1204 static var_entry *
1205 find_var_ent(uschar * name)
1206 {
1207 int first = 0;
1208 int last = var_table_size;
1209
1210 while (last > first)
1211   {
1212   int middle = (first + last)/2;
1213   int c = Ustrcmp(name, var_table[middle].name);
1214
1215   if (c > 0) { first = middle + 1; continue; }
1216   if (c < 0) { last = middle; continue; }
1217   return &var_table[middle];
1218   }
1219 return NULL;
1220 }
1221
1222 /*************************************************
1223 *   Extract numbered subfield from string        *
1224 *************************************************/
1225
1226 /* Extracts a numbered field from a string that is divided by tokens - for
1227 example a line from /etc/passwd is divided by colon characters.  First field is
1228 numbered one.  Negative arguments count from the right. Zero returns the whole
1229 string. Returns NULL if there are insufficient tokens in the string
1230
1231 ***WARNING***
1232 Modifies final argument - this is a dynamically generated string, so that's OK.
1233
1234 Arguments:
1235   field       number of field to be extracted,
1236                 first field = 1, whole string = 0, last field = -1
1237   separators  characters that are used to break string into tokens
1238   s           points to the string from which to extract the subfield
1239
1240 Returns:      NULL if the field was not found,
1241               a pointer to the field's data inside s (modified to add 0)
1242 */
1243
1244 static uschar *
1245 expand_gettokened (int field, uschar *separators, uschar *s)
1246 {
1247 int sep = 1;
1248 int count;
1249 uschar *ss = s;
1250 uschar *fieldtext = NULL;
1251
1252 if (field == 0) return s;
1253
1254 /* Break the line up into fields in place; for field > 0 we stop when we have
1255 done the number of fields we want. For field < 0 we continue till the end of
1256 the string, counting the number of fields. */
1257
1258 count = (field > 0)? field : INT_MAX;
1259
1260 while (count-- > 0)
1261   {
1262   size_t len;
1263
1264   /* Previous field was the last one in the string. For a positive field
1265   number, this means there are not enough fields. For a negative field number,
1266   check that there are enough, and scan back to find the one that is wanted. */
1267
1268   if (sep == 0)
1269     {
1270     if (field > 0 || (-field) > (INT_MAX - count - 1)) return NULL;
1271     if ((-field) == (INT_MAX - count - 1)) return s;
1272     while (field++ < 0)
1273       {
1274       ss--;
1275       while (ss[-1] != 0) ss--;
1276       }
1277     fieldtext = ss;
1278     break;
1279     }
1280
1281   /* Previous field was not last in the string; save its start and put a
1282   zero at its end. */
1283
1284   fieldtext = ss;
1285   len = Ustrcspn(ss, separators);
1286   sep = ss[len];
1287   ss[len] = 0;
1288   ss += len + 1;
1289   }
1290
1291 return fieldtext;
1292 }
1293
1294
1295 static uschar *
1296 expand_getlistele(int field, const uschar * list)
1297 {
1298 const uschar * tlist = list;
1299 int sep = 0;
1300 uschar dummy;
1301
1302 if (field < 0)
1303   {
1304   for (field++; string_nextinlist(&tlist, &sep, &dummy, 1); ) field++;
1305   sep = 0;
1306   }
1307 if (field == 0) return NULL;
1308 while (--field > 0 && (string_nextinlist(&list, &sep, &dummy, 1))) ;
1309 return string_nextinlist(&list, &sep, NULL, 0);
1310 }
1311
1312
1313 /* Certificate fields, by name.  Worry about by-OID later */
1314 /* Names are chosen to not have common prefixes */
1315
1316 #ifndef DISABLE_TLS
1317 typedef struct
1318 {
1319 uschar * name;
1320 int      namelen;
1321 uschar * (*getfn)(void * cert, uschar * mod);
1322 } certfield;
1323 static certfield certfields[] =
1324 {                       /* linear search; no special order */
1325   { US"version",         7,  &tls_cert_version },
1326   { US"serial_number",   13, &tls_cert_serial_number },
1327   { US"subject",         7,  &tls_cert_subject },
1328   { US"notbefore",       9,  &tls_cert_not_before },
1329   { US"notafter",        8,  &tls_cert_not_after },
1330   { US"issuer",          6,  &tls_cert_issuer },
1331   { US"signature",       9,  &tls_cert_signature },
1332   { US"sig_algorithm",   13, &tls_cert_signature_algorithm },
1333   { US"subj_altname",    12, &tls_cert_subject_altname },
1334   { US"ocsp_uri",        8,  &tls_cert_ocsp_uri },
1335   { US"crl_uri",         7,  &tls_cert_crl_uri },
1336 };
1337
1338 static uschar *
1339 expand_getcertele(uschar * field, uschar * certvar)
1340 {
1341 var_entry * vp;
1342
1343 if (!(vp = find_var_ent(certvar)))
1344   {
1345   expand_string_message =
1346     string_sprintf("no variable named \"%s\"", certvar);
1347   return NULL;          /* Unknown variable name */
1348   }
1349 /* NB this stops us passing certs around in variable.  Might
1350 want to do that in future */
1351 if (vp->type != vtype_cert)
1352   {
1353   expand_string_message =
1354     string_sprintf("\"%s\" is not a certificate", certvar);
1355   return NULL;          /* Unknown variable name */
1356   }
1357 if (!*(void **)vp->value)
1358   return NULL;
1359
1360 if (*field >= '0' && *field <= '9')
1361   return tls_cert_ext_by_oid(*(void **)vp->value, field, 0);
1362
1363 for (certfield * cp = certfields;
1364      cp < certfields + nelem(certfields);
1365      cp++)
1366   if (Ustrncmp(cp->name, field, cp->namelen) == 0)
1367     {
1368     uschar * modifier = *(field += cp->namelen) == ','
1369       ? ++field : NULL;
1370     return (*cp->getfn)( *(void **)vp->value, modifier );
1371     }
1372
1373 expand_string_message =
1374   string_sprintf("bad field selector \"%s\" for certextract", field);
1375 return NULL;
1376 }
1377 #endif  /*DISABLE_TLS*/
1378
1379 /*************************************************
1380 *        Extract a substring from a string       *
1381 *************************************************/
1382
1383 /* Perform the ${substr or ${length expansion operations.
1384
1385 Arguments:
1386   subject     the input string
1387   value1      the offset from the start of the input string to the start of
1388                 the output string; if negative, count from the right.
1389   value2      the length of the output string, or negative (-1) for unset
1390                 if value1 is positive, unset means "all after"
1391                 if value1 is negative, unset means "all before"
1392   len         set to the length of the returned string
1393
1394 Returns:      pointer to the output string, or NULL if there is an error
1395 */
1396
1397 static uschar *
1398 extract_substr(uschar *subject, int value1, int value2, int *len)
1399 {
1400 int sublen = Ustrlen(subject);
1401
1402 if (value1 < 0)    /* count from right */
1403   {
1404   value1 += sublen;
1405
1406   /* If the position is before the start, skip to the start, and adjust the
1407   length. If the length ends up negative, the substring is null because nothing
1408   can precede. This falls out naturally when the length is unset, meaning "all
1409   to the left". */
1410
1411   if (value1 < 0)
1412     {
1413     value2 += value1;
1414     if (value2 < 0) value2 = 0;
1415     value1 = 0;
1416     }
1417
1418   /* Otherwise an unset length => characters before value1 */
1419
1420   else if (value2 < 0)
1421     {
1422     value2 = value1;
1423     value1 = 0;
1424     }
1425   }
1426
1427 /* For a non-negative offset, if the starting position is past the end of the
1428 string, the result will be the null string. Otherwise, an unset length means
1429 "rest"; just set it to the maximum - it will be cut down below if necessary. */
1430
1431 else
1432   {
1433   if (value1 > sublen)
1434     {
1435     value1 = sublen;
1436     value2 = 0;
1437     }
1438   else if (value2 < 0) value2 = sublen;
1439   }
1440
1441 /* Cut the length down to the maximum possible for the offset value, and get
1442 the required characters. */
1443
1444 if (value1 + value2 > sublen) value2 = sublen - value1;
1445 *len = value2;
1446 return subject + value1;
1447 }
1448
1449
1450
1451
1452 /*************************************************
1453 *            Old-style hash of a string          *
1454 *************************************************/
1455
1456 /* Perform the ${hash expansion operation.
1457
1458 Arguments:
1459   subject     the input string (an expanded substring)
1460   value1      the length of the output string; if greater or equal to the
1461                 length of the input string, the input string is returned
1462   value2      the number of hash characters to use, or 26 if negative
1463   len         set to the length of the returned string
1464
1465 Returns:      pointer to the output string, or NULL if there is an error
1466 */
1467
1468 static uschar *
1469 compute_hash(uschar *subject, int value1, int value2, int *len)
1470 {
1471 int sublen = Ustrlen(subject);
1472
1473 if (value2 < 0) value2 = 26;
1474 else if (value2 > Ustrlen(hashcodes))
1475   {
1476   expand_string_message =
1477     string_sprintf("hash count \"%d\" too big", value2);
1478   return NULL;
1479   }
1480
1481 /* Calculate the hash text. We know it is shorter than the original string, so
1482 can safely place it in subject[] (we know that subject is always itself an
1483 expanded substring). */
1484
1485 if (value1 < sublen)
1486   {
1487   int c;
1488   int i = 0;
1489   int j = value1;
1490   while ((c = (subject[j])) != 0)
1491     {
1492     int shift = (c + j++) & 7;
1493     subject[i] ^= (c << shift) | (c >> (8-shift));
1494     if (++i >= value1) i = 0;
1495     }
1496   for (i = 0; i < value1; i++)
1497     subject[i] = hashcodes[(subject[i]) % value2];
1498   }
1499 else value1 = sublen;
1500
1501 *len = value1;
1502 return subject;
1503 }
1504
1505
1506
1507
1508 /*************************************************
1509 *             Numeric hash of a string           *
1510 *************************************************/
1511
1512 /* Perform the ${nhash expansion operation. The first characters of the
1513 string are treated as most important, and get the highest prime numbers.
1514
1515 Arguments:
1516   subject     the input string
1517   value1      the maximum value of the first part of the result
1518   value2      the maximum value of the second part of the result,
1519                 or negative to produce only a one-part result
1520   len         set to the length of the returned string
1521
1522 Returns:  pointer to the output string, or NULL if there is an error.
1523 */
1524
1525 static uschar *
1526 compute_nhash (uschar *subject, int value1, int value2, int *len)
1527 {
1528 uschar *s = subject;
1529 int i = 0;
1530 unsigned long int total = 0; /* no overflow */
1531
1532 while (*s != 0)
1533   {
1534   if (i == 0) i = nelem(prime) - 1;
1535   total += prime[i--] * (unsigned int)(*s++);
1536   }
1537
1538 /* If value2 is unset, just compute one number */
1539
1540 if (value2 < 0)
1541   s = string_sprintf("%lu", total % value1);
1542
1543 /* Otherwise do a div/mod hash */
1544
1545 else
1546   {
1547   total = total % (value1 * value2);
1548   s = string_sprintf("%lu/%lu", total/value2, total % value2);
1549   }
1550
1551 *len = Ustrlen(s);
1552 return s;
1553 }
1554
1555
1556
1557
1558
1559 /*************************************************
1560 *     Find the value of a header or headers      *
1561 *************************************************/
1562
1563 /* Multiple instances of the same header get concatenated, and this function
1564 can also return a concatenation of all the header lines. When concatenating
1565 specific headers that contain lists of addresses, a comma is inserted between
1566 them. Otherwise we use a straight concatenation. Because some messages can have
1567 pathologically large number of lines, there is a limit on the length that is
1568 returned.
1569
1570 Arguments:
1571   name          the name of the header, without the leading $header_ or $h_,
1572                 or NULL if a concatenation of all headers is required
1573   newsize       return the size of memory block that was obtained; may be NULL
1574                 if exists_only is TRUE
1575   flags         FH_EXISTS_ONLY
1576                   set if called from a def: test; don't need to build a string;
1577                   just return a string that is not "" and not "0" if the header
1578                   exists
1579                 FH_WANT_RAW
1580                   set if called for $rh_ or $rheader_ items; no processing,
1581                   other than concatenating, will be done on the header. Also used
1582                   for $message_headers_raw.
1583                 FH_WANT_LIST
1584                   Double colon chars in the content, and replace newline with
1585                   colon between each element when concatenating; returning a
1586                   colon-sep list (elements might contain newlines)
1587   charset       name of charset to translate MIME words to; used only if
1588                 want_raw is false; if NULL, no translation is done (this is
1589                 used for $bh_ and $bheader_)
1590
1591 Returns:        NULL if the header does not exist, else a pointer to a new
1592                 store block
1593 */
1594
1595 static uschar *
1596 find_header(uschar *name, int *newsize, unsigned flags, uschar *charset)
1597 {
1598 BOOL found = !name;
1599 int len = name ? Ustrlen(name) : 0;
1600 BOOL comma = FALSE;
1601 gstring * g = NULL;
1602
1603 for (header_line * h = header_list; h; h = h->next)
1604   if (h->type != htype_old && h->text)  /* NULL => Received: placeholder */
1605     if (!name || (len <= h->slen && strncmpic(name, h->text, len) == 0))
1606       {
1607       uschar * s, * t;
1608       size_t inc;
1609
1610       if (flags & FH_EXISTS_ONLY)
1611         return US"1";  /* don't need actual string */
1612
1613       found = TRUE;
1614       s = h->text + len;                /* text to insert */
1615       if (!(flags & FH_WANT_RAW))       /* unless wanted raw, */
1616         while (isspace(*s)) s++;        /* remove leading white space */
1617       t = h->text + h->slen;            /* end-point */
1618
1619       /* Unless wanted raw, remove trailing whitespace, including the
1620       newline. */
1621
1622       if (flags & FH_WANT_LIST)
1623         while (t > s && t[-1] == '\n') t--;
1624       else if (!(flags & FH_WANT_RAW))
1625         {
1626         while (t > s && isspace(t[-1])) t--;
1627
1628         /* Set comma if handling a single header and it's one of those
1629         that contains an address list, except when asked for raw headers. Only
1630         need to do this once. */
1631
1632         if (name && !comma && Ustrchr("BCFRST", h->type)) comma = TRUE;
1633         }
1634
1635       /* Trim the header roughly if we're approaching limits */
1636       inc = t - s;
1637       if (gstring_length(g) + inc > header_insert_maxlen)
1638         inc = header_insert_maxlen - gstring_length(g);
1639
1640       /* For raw just copy the data; for a list, add the data as a colon-sep
1641       list-element; for comma-list add as an unchecked comma,newline sep
1642       list-elemment; for other nonraw add as an unchecked newline-sep list (we
1643       stripped trailing WS above including the newline). We ignore the potential
1644       expansion due to colon-doubling, just leaving the loop if the limit is met
1645       or exceeded. */
1646
1647       if (flags & FH_WANT_LIST)
1648         g = string_append_listele_n(g, ':', s, (unsigned)inc);
1649       else if (flags & FH_WANT_RAW)
1650         g = string_catn(g, s, (unsigned)inc);
1651       else if (inc > 0)
1652         g = string_append2_listele_n(g, comma ? US",\n" : US"\n",
1653           s, (unsigned)inc);
1654
1655       if (gstring_length(g) >= header_insert_maxlen) break;
1656       }
1657
1658 if (!found) return NULL;        /* No header found */
1659 if (!g) return US"";
1660
1661 /* That's all we do for raw header expansion. */
1662
1663 *newsize = g->size;
1664 if (flags & FH_WANT_RAW)
1665   return string_from_gstring(g);
1666
1667 /* Otherwise do RFC 2047 decoding, translating the charset if requested.
1668 The rfc2047_decode2() function can return an error with decoded data if the
1669 charset translation fails. If decoding fails, it returns NULL. */
1670
1671 else
1672   {
1673   uschar * error, * decoded = rfc2047_decode2(string_from_gstring(g),
1674     check_rfc2047_length, charset, '?', NULL, newsize, &error);
1675   if (error)
1676     DEBUG(D_any) debug_printf("*** error in RFC 2047 decoding: %s\n"
1677       "    input was: %s\n", error, g->s);
1678   return decoded ? decoded : string_from_gstring(g);
1679   }
1680 }
1681
1682
1683
1684
1685 /* Append a "local" element to an Authentication-Results: header
1686 if this was a non-smtp message.
1687 */
1688
1689 static gstring *
1690 authres_local(gstring * g, const uschar * sysname)
1691 {
1692 if (!f.authentication_local)
1693   return g;
1694 g = string_append(g, 3, US";\n\tlocal=pass (non-smtp, ", sysname, US")");
1695 if (authenticated_id) g = string_append(g, 2, " u=", authenticated_id);
1696 return g;
1697 }
1698
1699
1700 /* Append an "iprev" element to an Authentication-Results: header
1701 if we have attempted to get the calling host's name.
1702 */
1703
1704 static gstring *
1705 authres_iprev(gstring * g)
1706 {
1707 if (sender_host_name)
1708   g = string_append(g, 3, US";\n\tiprev=pass (", sender_host_name, US")");
1709 else if (host_lookup_deferred)
1710   g = string_catn(g, US";\n\tiprev=temperror", 19);
1711 else if (host_lookup_failed)
1712   g = string_catn(g, US";\n\tiprev=fail", 13);
1713 else
1714   return g;
1715
1716 if (sender_host_address)
1717   g = string_append(g, 2, US" smtp.remote-ip=", sender_host_address);
1718 return g;
1719 }
1720
1721
1722
1723 /*************************************************
1724 *               Return list of recipients        *
1725 *************************************************/
1726 /* A recipients list is available only during system message filtering,
1727 during ACL processing after DATA, and while expanding pipe commands
1728 generated from a system filter, but not elsewhere. */
1729
1730 static uschar *
1731 fn_recipients(void)
1732 {
1733 uschar * s;
1734 gstring * g = NULL;
1735
1736 if (!f.enable_dollar_recipients) return NULL;
1737
1738 for (int i = 0; i < recipients_count; i++)
1739   {
1740   s = recipients_list[i].address;
1741   g = string_append2_listele_n(g, US", ", s, Ustrlen(s));
1742   }
1743 return g ? g->s : NULL;
1744 }
1745
1746
1747 /*************************************************
1748 *               Return size of queue             *
1749 *************************************************/
1750 /* Ask the daemon for the queue size */
1751
1752 static uschar *
1753 fn_queue_size(void)
1754 {
1755 struct sockaddr_un sa_un = {.sun_family = AF_UNIX};
1756 uschar buf[16];
1757 int fd;
1758 ssize_t len;
1759 const uschar * where;
1760 #ifndef EXIM_HAVE_ABSTRACT_UNIX_SOCKETS
1761 uschar * sname;
1762 #endif
1763 fd_set fds;
1764 struct timeval tv;
1765
1766 if ((fd = socket(AF_UNIX, SOCK_DGRAM, 0)) < 0)
1767   {
1768   DEBUG(D_expand) debug_printf(" socket: %s\n", strerror(errno));
1769   return NULL;
1770   }
1771
1772 #ifdef EXIM_HAVE_ABSTRACT_UNIX_SOCKETS
1773 sa_un.sun_path[0] = 0;  /* Abstract local socket addr - Linux-specific? */
1774 len = offsetof(struct sockaddr_un, sun_path) + 1
1775   + snprintf(sa_un.sun_path+1, sizeof(sa_un.sun_path)-1, "exim_%d", getpid());
1776 #else
1777 sname = string_sprintf("%s/p_%d", spool_directory, getpid());
1778 len = offsetof(struct sockaddr_un, sun_path)
1779   + snprintf(sa_un.sun_path, sizeof(sa_un.sun_path), "%s", sname);
1780 #endif
1781
1782 if (bind(fd, (const struct sockaddr *)&sa_un, len) < 0)
1783   { where = US"bind"; goto bad; }
1784
1785 #ifdef notdef
1786 debug_printf("local addr '%s%s'\n",
1787   *sa_un.sun_path ? "" : "@",
1788   sa_un.sun_path + (*sa_un.sun_path ? 0 : 1));
1789 #endif
1790
1791 #ifdef EXIM_HAVE_ABSTRACT_UNIX_SOCKETS
1792 sa_un.sun_path[0] = 0;  /* Abstract local socket addr - Linux-specific? */
1793 len = offsetof(struct sockaddr_un, sun_path) + 1
1794   + snprintf(sa_un.sun_path+1, sizeof(sa_un.sun_path)-1, "%s", NOTIFIER_SOCKET_NAME);
1795 #else
1796 len = offsetof(struct sockaddr_un, sun_path)
1797   + snprintf(sa_un.sun_path, sizeof(sa_un.sun_path), "%s/%s",
1798                 spool_directory, NOTIFIER_SOCKET_NAME);
1799 #endif
1800
1801 if (connect(fd, (const struct sockaddr *)&sa_un, len) < 0)
1802   { where = US"connect"; goto bad2; }
1803
1804 buf[0] = NOTIFY_QUEUE_SIZE_REQ;
1805 if (send(fd, buf, 1, 0) < 0) { where = US"send"; goto bad; }
1806
1807 FD_ZERO(&fds); FD_SET(fd, &fds);
1808 tv.tv_sec = 2; tv.tv_usec = 0;
1809 if (select(fd + 1, (SELECT_ARG2_TYPE *)&fds, NULL, NULL, &tv) != 1)
1810   {
1811   DEBUG(D_expand) debug_printf("no daemon response; using local evaluation\n");
1812   len = snprintf(CS buf, sizeof(buf), "%u", queue_count_cached());
1813   }
1814 else if ((len = recv(fd, buf, sizeof(buf), 0)) < 0)
1815   { where = US"recv"; goto bad2; }
1816
1817 close(fd);
1818 #ifndef EXIM_HAVE_ABSTRACT_UNIX_SOCKETS
1819 Uunlink(sname);
1820 #endif
1821 return string_copyn(buf, len);
1822
1823 bad2:
1824 #ifndef EXIM_HAVE_ABSTRACT_UNIX_SOCKETS
1825   Uunlink(sname);
1826 #endif
1827 bad:
1828   close(fd);
1829   DEBUG(D_expand) debug_printf(" %s: %s\n", where, strerror(errno));
1830   return NULL;
1831 }
1832
1833
1834 /*************************************************
1835 *               Find value of a variable         *
1836 *************************************************/
1837
1838 /* The table of variables is kept in alphabetic order, so we can search it
1839 using a binary chop. The "choplen" variable is nothing to do with the binary
1840 chop.
1841
1842 Arguments:
1843   name          the name of the variable being sought
1844   exists_only   TRUE if this is a def: test; passed on to find_header()
1845   skipping      TRUE => skip any processing evaluation; this is not the same as
1846                   exists_only because def: may test for values that are first
1847                   evaluated here
1848   newsize       pointer to an int which is initially zero; if the answer is in
1849                 a new memory buffer, *newsize is set to its size
1850
1851 Returns:        NULL if the variable does not exist, or
1852                 a pointer to the variable's contents, or
1853                 something non-NULL if exists_only is TRUE
1854 */
1855
1856 static uschar *
1857 find_variable(uschar *name, BOOL exists_only, BOOL skipping, int *newsize)
1858 {
1859 var_entry * vp;
1860 uschar *s, *domain;
1861 uschar **ss;
1862 void * val;
1863
1864 /* Handle ACL variables, whose names are of the form acl_cxxx or acl_mxxx.
1865 Originally, xxx had to be a number in the range 0-9 (later 0-19), but from
1866 release 4.64 onwards arbitrary names are permitted, as long as the first 5
1867 characters are acl_c or acl_m and the sixth is either a digit or an underscore
1868 (this gave backwards compatibility at the changeover). There may be built-in
1869 variables whose names start acl_ but they should never start in this way. This
1870 slightly messy specification is a consequence of the history, needless to say.
1871
1872 If an ACL variable does not exist, treat it as empty, unless strict_acl_vars is
1873 set, in which case give an error. */
1874
1875 if ((Ustrncmp(name, "acl_c", 5) == 0 || Ustrncmp(name, "acl_m", 5) == 0) &&
1876      !isalpha(name[5]))
1877   {
1878   tree_node * node =
1879     tree_search(name[4] == 'c' ? acl_var_c : acl_var_m, name + 4);
1880   return node ? node->data.ptr : strict_acl_vars ? NULL : US"";
1881   }
1882 else if (Ustrncmp(name, "r_", 2) == 0)
1883   {
1884   tree_node * node = tree_search(router_var, name + 2);
1885   return node ? node->data.ptr : strict_acl_vars ? NULL : US"";
1886   }
1887
1888 /* Handle $auth<n> variables. */
1889
1890 if (Ustrncmp(name, "auth", 4) == 0)
1891   {
1892   uschar *endptr;
1893   int n = Ustrtoul(name + 4, &endptr, 10);
1894   if (*endptr == 0 && n != 0 && n <= AUTH_VARS)
1895     return !auth_vars[n-1] ? US"" : auth_vars[n-1];
1896   }
1897 else if (Ustrncmp(name, "regex", 5) == 0)
1898   {
1899   uschar *endptr;
1900   int n = Ustrtoul(name + 5, &endptr, 10);
1901   if (*endptr == 0 && n != 0 && n <= REGEX_VARS)
1902     return !regex_vars[n-1] ? US"" : regex_vars[n-1];
1903   }
1904
1905 /* For all other variables, search the table */
1906
1907 if (!(vp = find_var_ent(name)))
1908   return NULL;          /* Unknown variable name */
1909
1910 /* Found an existing variable. If in skipping state, the value isn't needed,
1911 and we want to avoid processing (such as looking up the host name). */
1912
1913 if (skipping)
1914   return US"";
1915
1916 val = vp->value;
1917 switch (vp->type)
1918   {
1919   case vtype_filter_int:
1920     if (!f.filter_running) return NULL;
1921     /* Fall through */
1922     /* VVVVVVVVVVVV */
1923   case vtype_int:
1924     sprintf(CS var_buffer, "%d", *(int *)(val)); /* Integer */
1925     return var_buffer;
1926
1927   case vtype_ino:
1928     sprintf(CS var_buffer, "%ld", (long int)(*(ino_t *)(val))); /* Inode */
1929     return var_buffer;
1930
1931   case vtype_gid:
1932     sprintf(CS var_buffer, "%ld", (long int)(*(gid_t *)(val))); /* gid */
1933     return var_buffer;
1934
1935   case vtype_uid:
1936     sprintf(CS var_buffer, "%ld", (long int)(*(uid_t *)(val))); /* uid */
1937     return var_buffer;
1938
1939   case vtype_bool:
1940     sprintf(CS var_buffer, "%s", *(BOOL *)(val) ? "yes" : "no"); /* bool */
1941     return var_buffer;
1942
1943   case vtype_stringptr:                      /* Pointer to string */
1944     return (s = *((uschar **)(val))) ? s : US"";
1945
1946   case vtype_pid:
1947     sprintf(CS var_buffer, "%d", (int)getpid()); /* pid */
1948     return var_buffer;
1949
1950   case vtype_load_avg:
1951     sprintf(CS var_buffer, "%d", OS_GETLOADAVG()); /* load_average */
1952     return var_buffer;
1953
1954   case vtype_host_lookup:                    /* Lookup if not done so */
1955     if (  !sender_host_name && sender_host_address
1956        && !host_lookup_failed && host_name_lookup() == OK)
1957       host_build_sender_fullhost();
1958     return sender_host_name ? sender_host_name : US"";
1959
1960   case vtype_localpart:                      /* Get local part from address */
1961     if (!(s = *((uschar **)(val)))) return US"";
1962     if (!(domain = Ustrrchr(s, '@'))) return s;
1963     if (domain - s > sizeof(var_buffer) - 1)
1964       log_write(0, LOG_MAIN|LOG_PANIC_DIE, "local part longer than " SIZE_T_FMT
1965           " in string expansion", sizeof(var_buffer));
1966     return string_copyn(s, domain - s);
1967
1968   case vtype_domain:                         /* Get domain from address */
1969     if (!(s = *((uschar **)(val)))) return US"";
1970     domain = Ustrrchr(s, '@');
1971     return domain ? domain + 1 : US"";
1972
1973   case vtype_msgheaders:
1974     return find_header(NULL, newsize, exists_only ? FH_EXISTS_ONLY : 0, NULL);
1975
1976   case vtype_msgheaders_raw:
1977     return find_header(NULL, newsize,
1978                 exists_only ? FH_EXISTS_ONLY|FH_WANT_RAW : FH_WANT_RAW, NULL);
1979
1980   case vtype_msgbody:                        /* Pointer to msgbody string */
1981   case vtype_msgbody_end:                    /* Ditto, the end of the msg */
1982     ss = (uschar **)(val);
1983     if (!*ss && deliver_datafile >= 0)  /* Read body when needed */
1984       {
1985       uschar *body;
1986       off_t start_offset = SPOOL_DATA_START_OFFSET;
1987       int len = message_body_visible;
1988       if (len > message_size) len = message_size;
1989       *ss = body = store_malloc(len+1);
1990       body[0] = 0;
1991       if (vp->type == vtype_msgbody_end)
1992         {
1993         struct stat statbuf;
1994         if (fstat(deliver_datafile, &statbuf) == 0)
1995           {
1996           start_offset = statbuf.st_size - len;
1997           if (start_offset < SPOOL_DATA_START_OFFSET)
1998             start_offset = SPOOL_DATA_START_OFFSET;
1999           }
2000         }
2001       if (lseek(deliver_datafile, start_offset, SEEK_SET) < 0)
2002         log_write(0, LOG_MAIN|LOG_PANIC_DIE, "deliver_datafile lseek: %s",
2003           strerror(errno));
2004       len = read(deliver_datafile, body, len);
2005       if (len > 0)
2006         {
2007         body[len] = 0;
2008         if (message_body_newlines)   /* Separate loops for efficiency */
2009           while (len > 0)
2010             { if (body[--len] == 0) body[len] = ' '; }
2011         else
2012           while (len > 0)
2013             { if (body[--len] == '\n' || body[len] == 0) body[len] = ' '; }
2014         }
2015       }
2016     return *ss ? *ss : US"";
2017
2018   case vtype_todbsdin:                       /* BSD inbox time of day */
2019     return tod_stamp(tod_bsdin);
2020
2021   case vtype_tode:                           /* Unix epoch time of day */
2022     return tod_stamp(tod_epoch);
2023
2024   case vtype_todel:                          /* Unix epoch/usec time of day */
2025     return tod_stamp(tod_epoch_l);
2026
2027   case vtype_todf:                           /* Full time of day */
2028     return tod_stamp(tod_full);
2029
2030   case vtype_todl:                           /* Log format time of day */
2031     return tod_stamp(tod_log_bare);            /* (without timezone) */
2032
2033   case vtype_todzone:                        /* Time zone offset only */
2034     return tod_stamp(tod_zone);
2035
2036   case vtype_todzulu:                        /* Zulu time */
2037     return tod_stamp(tod_zulu);
2038
2039   case vtype_todlf:                          /* Log file datestamp tod */
2040     return tod_stamp(tod_log_datestamp_daily);
2041
2042   case vtype_reply:                          /* Get reply address */
2043     s = find_header(US"reply-to:", newsize,
2044                 exists_only ? FH_EXISTS_ONLY|FH_WANT_RAW : FH_WANT_RAW,
2045                 headers_charset);
2046     if (s) while (isspace(*s)) s++;
2047     if (!s || !*s)
2048       {
2049       *newsize = 0;                            /* For the *s==0 case */
2050       s = find_header(US"from:", newsize,
2051                 exists_only ? FH_EXISTS_ONLY|FH_WANT_RAW : FH_WANT_RAW,
2052                 headers_charset);
2053       }
2054     if (s)
2055       {
2056       uschar *t;
2057       while (isspace(*s)) s++;
2058       for (t = s; *t != 0; t++) if (*t == '\n') *t = ' ';
2059       while (t > s && isspace(t[-1])) t--;
2060       *t = 0;
2061       }
2062     return s ? s : US"";
2063
2064   case vtype_string_func:
2065     {
2066     stringptr_fn_t * fn = (stringptr_fn_t *) val;
2067     return fn();
2068     }
2069
2070   case vtype_pspace:
2071     {
2072     int inodes;
2073     sprintf(CS var_buffer, PR_EXIM_ARITH,
2074       receive_statvfs(val == (void *)TRUE, &inodes));
2075     }
2076   return var_buffer;
2077
2078   case vtype_pinodes:
2079     {
2080     int inodes;
2081     (void) receive_statvfs(val == (void *)TRUE, &inodes);
2082     sprintf(CS var_buffer, "%d", inodes);
2083     }
2084   return var_buffer;
2085
2086   case vtype_cert:
2087     return *(void **)val ? US"<cert>" : US"";
2088
2089 #ifndef DISABLE_DKIM
2090   case vtype_dkim:
2091     return dkim_exim_expand_query((int)(long)val);
2092 #endif
2093
2094   }
2095
2096 return NULL;  /* Unknown variable. Silences static checkers. */
2097 }
2098
2099
2100
2101
2102 void
2103 modify_variable(uschar *name, void * value)
2104 {
2105 var_entry * vp;
2106 if ((vp = find_var_ent(name))) vp->value = value;
2107 return;          /* Unknown variable name, fail silently */
2108 }
2109
2110
2111
2112
2113
2114
2115 /*************************************************
2116 *           Read and expand substrings           *
2117 *************************************************/
2118
2119 /* This function is called to read and expand argument substrings for various
2120 expansion items. Some have a minimum requirement that is less than the maximum;
2121 in these cases, the first non-present one is set to NULL.
2122
2123 Arguments:
2124   sub        points to vector of pointers to set
2125   n          maximum number of substrings
2126   m          minimum required
2127   sptr       points to current string pointer
2128   skipping   the skipping flag
2129   check_end  if TRUE, check for final '}'
2130   name       name of item, for error message
2131   resetok    if not NULL, pointer to flag - write FALSE if unsafe to reset
2132              the store.
2133
2134 Returns:     0 OK; string pointer updated
2135              1 curly bracketing error (too few arguments)
2136              2 too many arguments (only if check_end is set); message set
2137              3 other error (expansion failure)
2138 */
2139
2140 static int
2141 read_subs(uschar **sub, int n, int m, const uschar **sptr, BOOL skipping,
2142   BOOL check_end, uschar *name, BOOL *resetok)
2143 {
2144 const uschar *s = *sptr;
2145
2146 while (isspace(*s)) s++;
2147 for (int i = 0; i < n; i++)
2148   {
2149   if (*s != '{')
2150     {
2151     if (i < m)
2152       {
2153       expand_string_message = string_sprintf("Not enough arguments for '%s' "
2154         "(min is %d)", name, m);
2155       return 1;
2156       }
2157     sub[i] = NULL;
2158     break;
2159     }
2160   if (!(sub[i] = expand_string_internal(s+1, TRUE, &s, skipping, TRUE, resetok)))
2161     return 3;
2162   if (*s++ != '}') return 1;
2163   while (isspace(*s)) s++;
2164   }
2165 if (check_end && *s++ != '}')
2166   {
2167   if (s[-1] == '{')
2168     {
2169     expand_string_message = string_sprintf("Too many arguments for '%s' "
2170       "(max is %d)", name, n);
2171     return 2;
2172     }
2173   expand_string_message = string_sprintf("missing '}' after '%s'", name);
2174   return 1;
2175   }
2176
2177 *sptr = s;
2178 return 0;
2179 }
2180
2181
2182
2183
2184 /*************************************************
2185 *     Elaborate message for bad variable         *
2186 *************************************************/
2187
2188 /* For the "unknown variable" message, take a look at the variable's name, and
2189 give additional information about possible ACL variables. The extra information
2190 is added on to expand_string_message.
2191
2192 Argument:   the name of the variable
2193 Returns:    nothing
2194 */
2195
2196 static void
2197 check_variable_error_message(uschar *name)
2198 {
2199 if (Ustrncmp(name, "acl_", 4) == 0)
2200   expand_string_message = string_sprintf("%s (%s)", expand_string_message,
2201     (name[4] == 'c' || name[4] == 'm')?
2202       (isalpha(name[5])?
2203         US"6th character of a user-defined ACL variable must be a digit or underscore" :
2204         US"strict_acl_vars is set"    /* Syntax is OK, it has to be this */
2205       ) :
2206       US"user-defined ACL variables must start acl_c or acl_m");
2207 }
2208
2209
2210
2211 /*
2212 Load args from sub array to globals, and call acl_check().
2213 Sub array will be corrupted on return.
2214
2215 Returns:       OK         access is granted by an ACCEPT verb
2216                DISCARD    access is (apparently) granted by a DISCARD verb
2217                FAIL       access is denied
2218                FAIL_DROP  access is denied; drop the connection
2219                DEFER      can't tell at the moment
2220                ERROR      disaster
2221 */
2222 static int
2223 eval_acl(uschar ** sub, int nsub, uschar ** user_msgp)
2224 {
2225 int i;
2226 int sav_narg = acl_narg;
2227 int ret;
2228 uschar * dummy_logmsg;
2229 extern int acl_where;
2230
2231 if(--nsub > nelem(acl_arg)) nsub = nelem(acl_arg);
2232 for (i = 0; i < nsub && sub[i+1]; i++)
2233   {
2234   uschar * tmp = acl_arg[i];
2235   acl_arg[i] = sub[i+1];        /* place callers args in the globals */
2236   sub[i+1] = tmp;               /* stash the old args using our caller's storage */
2237   }
2238 acl_narg = i;
2239 while (i < nsub)
2240   {
2241   sub[i+1] = acl_arg[i];
2242   acl_arg[i++] = NULL;
2243   }
2244
2245 DEBUG(D_expand)
2246   debug_printf_indent("expanding: acl: %s  arg: %s%s\n",
2247     sub[0],
2248     acl_narg>0 ? acl_arg[0] : US"<none>",
2249     acl_narg>1 ? " +more"   : "");
2250
2251 ret = acl_eval(acl_where, sub[0], user_msgp, &dummy_logmsg);
2252
2253 for (i = 0; i < nsub; i++)
2254   acl_arg[i] = sub[i+1];        /* restore old args */
2255 acl_narg = sav_narg;
2256
2257 return ret;
2258 }
2259
2260
2261
2262
2263 /* Return pointer to dewrapped string, with enclosing specified chars removed.
2264 The given string is modified on return.  Leading whitespace is skipped while
2265 looking for the opening wrap character, then the rest is scanned for the trailing
2266 (non-escaped) wrap character.  A backslash in the string will act as an escape.
2267
2268 A nul is written over the trailing wrap, and a pointer to the char after the
2269 leading wrap is returned.
2270
2271 Arguments:
2272   s     String for de-wrapping
2273   wrap  Two-char string, the first being the opener, second the closer wrapping
2274         character
2275 Return:
2276   Pointer to de-wrapped string, or NULL on error (with expand_string_message set).
2277 */
2278
2279 static uschar *
2280 dewrap(uschar * s, const uschar * wrap)
2281 {
2282 uschar * p = s;
2283 unsigned depth = 0;
2284 BOOL quotesmode = wrap[0] == wrap[1];
2285
2286 while (isspace(*p)) p++;
2287
2288 if (*p == *wrap)
2289   {
2290   s = ++p;
2291   wrap++;
2292   while (*p)
2293     {
2294     if (*p == '\\') p++;
2295     else if (!quotesmode && *p == wrap[-1]) depth++;
2296     else if (*p == *wrap)
2297       if (depth == 0)
2298         {
2299         *p = '\0';
2300         return s;
2301         }
2302       else
2303         depth--;
2304     p++;
2305     }
2306   }
2307 expand_string_message = string_sprintf("missing '%c'", *wrap);
2308 return NULL;
2309 }
2310
2311
2312 /* Pull off the leading array or object element, returning
2313 a copy in an allocated string.  Update the list pointer.
2314
2315 The element may itself be an abject or array.
2316 Return NULL when the list is empty.
2317 */
2318
2319 static uschar *
2320 json_nextinlist(const uschar ** list)
2321 {
2322 unsigned array_depth = 0, object_depth = 0;
2323 const uschar * s = *list, * item;
2324
2325 while (isspace(*s)) s++;
2326
2327 for (item = s;
2328      *s && (*s != ',' || array_depth != 0 || object_depth != 0);
2329      s++)
2330   switch (*s)
2331     {
2332     case '[': array_depth++; break;
2333     case ']': array_depth--; break;
2334     case '{': object_depth++; break;
2335     case '}': object_depth--; break;
2336     }
2337 *list = *s ? s+1 : s;
2338 if (item == s) return NULL;
2339 item = string_copyn(item, s - item);
2340 DEBUG(D_expand) debug_printf_indent("  json ele: '%s'\n", item);
2341 return US item;
2342 }
2343
2344
2345
2346 /************************************************/
2347 /*  Return offset in ops table, or -1 if not found.
2348 Repoint to just after the operator in the string.
2349
2350 Argument:
2351  ss     string representation of operator
2352  opname split-out operator name
2353 */
2354
2355 static int
2356 identify_operator(const uschar ** ss, uschar ** opname)
2357 {
2358 const uschar * s = *ss;
2359 uschar name[256];
2360
2361 /* Numeric comparisons are symbolic */
2362
2363 if (*s == '=' || *s == '>' || *s == '<')
2364   {
2365   int p = 0;
2366   name[p++] = *s++;
2367   if (*s == '=')
2368     {
2369     name[p++] = '=';
2370     s++;
2371     }
2372   name[p] = 0;
2373   }
2374
2375 /* All other conditions are named */
2376
2377 else
2378   s = read_name(name, sizeof(name), s, US"_");
2379 *ss = s;
2380
2381 /* If we haven't read a name, it means some non-alpha character is first. */
2382
2383 if (!name[0])
2384   {
2385   expand_string_message = string_sprintf("condition name expected, "
2386     "but found \"%.16s\"", s);
2387   return -1;
2388   }
2389 if (opname)
2390   *opname = string_copy(name);
2391
2392 return chop_match(name, cond_table, nelem(cond_table));
2393 }
2394
2395
2396 /*************************************************
2397 *    Handle MD5 or SHA-1 computation for HMAC    *
2398 *************************************************/
2399
2400 /* These are some wrapping functions that enable the HMAC code to be a bit
2401 cleaner. A good compiler will spot the tail recursion.
2402
2403 Arguments:
2404   type         HMAC_MD5 or HMAC_SHA1
2405   remaining    are as for the cryptographic hash functions
2406
2407 Returns:       nothing
2408 */
2409
2410 static void
2411 chash_start(int type, void * base)
2412 {
2413 if (type == HMAC_MD5)
2414   md5_start((md5 *)base);
2415 else
2416   sha1_start((hctx *)base);
2417 }
2418
2419 static void
2420 chash_mid(int type, void * base, const uschar * string)
2421 {
2422 if (type == HMAC_MD5)
2423   md5_mid((md5 *)base, string);
2424 else
2425   sha1_mid((hctx *)base, string);
2426 }
2427
2428 static void
2429 chash_end(int type, void * base, const uschar * string, int length,
2430   uschar * digest)
2431 {
2432 if (type == HMAC_MD5)
2433   md5_end((md5 *)base, string, length, digest);
2434 else
2435   sha1_end((hctx *)base, string, length, digest);
2436 }
2437
2438
2439
2440
2441 /* Do an hmac_md5.  The result is _not_ nul-terminated, and is sized as
2442 the smaller of a full hmac_md5 result (16 bytes) or the supplied output buffer.
2443
2444 Arguments:
2445         key     encoding key, nul-terminated
2446         src     data to be hashed, nul-terminated
2447         buf     output buffer
2448         len     size of output buffer
2449 */
2450
2451 static void
2452 hmac_md5(const uschar * key, const uschar * src, uschar * buf, unsigned len)
2453 {
2454 md5 md5_base;
2455 const uschar * keyptr;
2456 uschar * p;
2457 unsigned int keylen;
2458
2459 #define MD5_HASHLEN      16
2460 #define MD5_HASHBLOCKLEN 64
2461
2462 uschar keyhash[MD5_HASHLEN];
2463 uschar innerhash[MD5_HASHLEN];
2464 uschar finalhash[MD5_HASHLEN];
2465 uschar innerkey[MD5_HASHBLOCKLEN];
2466 uschar outerkey[MD5_HASHBLOCKLEN];
2467
2468 keyptr = key;
2469 keylen = Ustrlen(keyptr);
2470
2471 /* If the key is longer than the hash block length, then hash the key
2472 first */
2473
2474 if (keylen > MD5_HASHBLOCKLEN)
2475   {
2476   chash_start(HMAC_MD5, &md5_base);
2477   chash_end(HMAC_MD5, &md5_base, keyptr, keylen, keyhash);
2478   keyptr = keyhash;
2479   keylen = MD5_HASHLEN;
2480   }
2481
2482 /* Now make the inner and outer key values */
2483
2484 memset(innerkey, 0x36, MD5_HASHBLOCKLEN);
2485 memset(outerkey, 0x5c, MD5_HASHBLOCKLEN);
2486
2487 for (int i = 0; i < keylen; i++)
2488   {
2489   innerkey[i] ^= keyptr[i];
2490   outerkey[i] ^= keyptr[i];
2491   }
2492
2493 /* Now do the hashes */
2494
2495 chash_start(HMAC_MD5, &md5_base);
2496 chash_mid(HMAC_MD5, &md5_base, innerkey);
2497 chash_end(HMAC_MD5, &md5_base, src, Ustrlen(src), innerhash);
2498
2499 chash_start(HMAC_MD5, &md5_base);
2500 chash_mid(HMAC_MD5, &md5_base, outerkey);
2501 chash_end(HMAC_MD5, &md5_base, innerhash, MD5_HASHLEN, finalhash);
2502
2503 /* Encode the final hash as a hex string, limited by output buffer size */
2504
2505 p = buf;
2506 for (int i = 0, j = len; i < MD5_HASHLEN; i++)
2507   {
2508   if (j-- <= 0) break;
2509   *p++ = hex_digits[(finalhash[i] & 0xf0) >> 4];
2510   if (j-- <= 0) break;
2511   *p++ = hex_digits[finalhash[i] & 0x0f];
2512   }
2513 return;
2514 }
2515
2516
2517 /*************************************************
2518 *        Read and evaluate a condition           *
2519 *************************************************/
2520
2521 /*
2522 Arguments:
2523   s        points to the start of the condition text
2524   resetok  points to a BOOL which is written false if it is unsafe to
2525            free memory. Certain condition types (acl) may have side-effect
2526            allocation which must be preserved.
2527   yield    points to a BOOL to hold the result of the condition test;
2528            if NULL, we are just reading through a condition that is
2529            part of an "or" combination to check syntax, or in a state
2530            where the answer isn't required
2531
2532 Returns:   a pointer to the first character after the condition, or
2533            NULL after an error
2534 */
2535
2536 static const uschar *
2537 eval_condition(const uschar *s, BOOL *resetok, BOOL *yield)
2538 {
2539 BOOL testfor = TRUE;
2540 BOOL tempcond, combined_cond;
2541 BOOL *subcondptr;
2542 BOOL sub2_honour_dollar = TRUE;
2543 BOOL is_forany, is_json, is_jsons;
2544 int rc, cond_type, roffset;
2545 int_eximarith_t num[2];
2546 struct stat statbuf;
2547 uschar * opname;
2548 uschar name[256];
2549 const uschar *sub[10];
2550
2551 const pcre *re;
2552 const uschar *rerror;
2553
2554 for (;;)
2555   {
2556   while (isspace(*s)) s++;
2557   if (*s == '!') { testfor = !testfor; s++; } else break;
2558   }
2559
2560 switch(cond_type = identify_operator(&s, &opname))
2561   {
2562   /* def: tests for a non-empty variable, or for the existence of a header. If
2563   yield == NULL we are in a skipping state, and don't care about the answer. */
2564
2565   case ECOND_DEF:
2566     {
2567     uschar * t;
2568
2569     if (*s != ':')
2570       {
2571       expand_string_message = US"\":\" expected after \"def\"";
2572       return NULL;
2573       }
2574
2575     s = read_name(name, sizeof(name), s+1, US"_");
2576
2577     /* Test for a header's existence. If the name contains a closing brace
2578     character, this may be a user error where the terminating colon has been
2579     omitted. Set a flag to adjust a subsequent error message in this case. */
2580
2581     if (  ( *(t = name) == 'h'
2582           || (*t == 'r' || *t == 'l' || *t == 'b') && *++t == 'h'
2583           )
2584        && (*++t == '_' || Ustrncmp(t, "eader_", 6) == 0)
2585        )
2586       {
2587       s = read_header_name(name, sizeof(name), s);
2588       /* {-for-text-editors */
2589       if (Ustrchr(name, '}') != NULL) malformed_header = TRUE;
2590       if (yield) *yield =
2591         (find_header(name, NULL, FH_EXISTS_ONLY, NULL) != NULL) == testfor;
2592       }
2593
2594     /* Test for a variable's having a non-empty value. A non-existent variable
2595     causes an expansion failure. */
2596
2597     else
2598       {
2599       if (!(t = find_variable(name, TRUE, yield == NULL, NULL)))
2600         {
2601         expand_string_message = name[0]
2602           ? string_sprintf("unknown variable \"%s\" after \"def:\"", name)
2603           : US"variable name omitted after \"def:\"";
2604         check_variable_error_message(name);
2605         return NULL;
2606         }
2607       if (yield) *yield = (t[0] != 0) == testfor;
2608       }
2609
2610     return s;
2611     }
2612
2613
2614   /* first_delivery tests for first delivery attempt */
2615
2616   case ECOND_FIRST_DELIVERY:
2617   if (yield) *yield = f.deliver_firsttime == testfor;
2618   return s;
2619
2620
2621   /* queue_running tests for any process started by a queue runner */
2622
2623   case ECOND_QUEUE_RUNNING:
2624   if (yield) *yield = (queue_run_pid != (pid_t)0) == testfor;
2625   return s;
2626
2627
2628   /* exists:  tests for file existence
2629        isip:  tests for any IP address
2630       isip4:  tests for an IPv4 address
2631       isip6:  tests for an IPv6 address
2632         pam:  does PAM authentication
2633      radius:  does RADIUS authentication
2634    ldapauth:  does LDAP authentication
2635     pwcheck:  does Cyrus SASL pwcheck authentication
2636   */
2637
2638   case ECOND_EXISTS:
2639   case ECOND_ISIP:
2640   case ECOND_ISIP4:
2641   case ECOND_ISIP6:
2642   case ECOND_PAM:
2643   case ECOND_RADIUS:
2644   case ECOND_LDAPAUTH:
2645   case ECOND_PWCHECK:
2646
2647   while (isspace(*s)) s++;
2648   if (*s != '{') goto COND_FAILED_CURLY_START;          /* }-for-text-editors */
2649
2650   sub[0] = expand_string_internal(s+1, TRUE, &s, yield == NULL, TRUE, resetok);
2651   if (!sub[0]) return NULL;
2652   /* {-for-text-editors */
2653   if (*s++ != '}') goto COND_FAILED_CURLY_END;
2654
2655   if (!yield) return s;   /* No need to run the test if skipping */
2656
2657   switch(cond_type)
2658     {
2659     case ECOND_EXISTS:
2660     if ((expand_forbid & RDO_EXISTS) != 0)
2661       {
2662       expand_string_message = US"File existence tests are not permitted";
2663       return NULL;
2664       }
2665     *yield = (Ustat(sub[0], &statbuf) == 0) == testfor;
2666     break;
2667
2668     case ECOND_ISIP:
2669     case ECOND_ISIP4:
2670     case ECOND_ISIP6:
2671     rc = string_is_ip_address(sub[0], NULL);
2672     *yield = ((cond_type == ECOND_ISIP)? (rc != 0) :
2673              (cond_type == ECOND_ISIP4)? (rc == 4) : (rc == 6)) == testfor;
2674     break;
2675
2676     /* Various authentication tests - all optionally compiled */
2677
2678     case ECOND_PAM:
2679     #ifdef SUPPORT_PAM
2680     rc = auth_call_pam(sub[0], &expand_string_message);
2681     goto END_AUTH;
2682     #else
2683     goto COND_FAILED_NOT_COMPILED;
2684     #endif  /* SUPPORT_PAM */
2685
2686     case ECOND_RADIUS:
2687     #ifdef RADIUS_CONFIG_FILE
2688     rc = auth_call_radius(sub[0], &expand_string_message);
2689     goto END_AUTH;
2690     #else
2691     goto COND_FAILED_NOT_COMPILED;
2692     #endif  /* RADIUS_CONFIG_FILE */
2693
2694     case ECOND_LDAPAUTH:
2695     #ifdef LOOKUP_LDAP
2696       {
2697       /* Just to keep the interface the same */
2698       BOOL do_cache;
2699       int old_pool = store_pool;
2700       store_pool = POOL_SEARCH;
2701       rc = eldapauth_find((void *)(-1), NULL, sub[0], Ustrlen(sub[0]), NULL,
2702         &expand_string_message, &do_cache);
2703       store_pool = old_pool;
2704       }
2705     goto END_AUTH;
2706     #else
2707     goto COND_FAILED_NOT_COMPILED;
2708     #endif  /* LOOKUP_LDAP */
2709
2710     case ECOND_PWCHECK:
2711     #ifdef CYRUS_PWCHECK_SOCKET
2712     rc = auth_call_pwcheck(sub[0], &expand_string_message);
2713     goto END_AUTH;
2714     #else
2715     goto COND_FAILED_NOT_COMPILED;
2716     #endif  /* CYRUS_PWCHECK_SOCKET */
2717
2718     #if defined(SUPPORT_PAM) || defined(RADIUS_CONFIG_FILE) || \
2719         defined(LOOKUP_LDAP) || defined(CYRUS_PWCHECK_SOCKET)
2720     END_AUTH:
2721     if (rc == ERROR || rc == DEFER) return NULL;
2722     *yield = (rc == OK) == testfor;
2723     #endif
2724     }
2725   return s;
2726
2727
2728   /* call ACL (in a conditional context).  Accept true, deny false.
2729   Defer is a forced-fail.  Anything set by message= goes to $value.
2730   Up to ten parameters are used; we use the braces round the name+args
2731   like the saslauthd condition does, to permit a variable number of args.
2732   See also the expansion-item version EITEM_ACL and the traditional
2733   acl modifier ACLC_ACL.
2734   Since the ACL may allocate new global variables, tell our caller to not
2735   reclaim memory.
2736   */
2737
2738   case ECOND_ACL:
2739     /* ${if acl {{name}{arg1}{arg2}...}  {yes}{no}} */
2740     {
2741     uschar *sub[10];
2742     uschar *user_msg;
2743     BOOL cond = FALSE;
2744
2745     while (isspace(*s)) s++;
2746     if (*s++ != '{') goto COND_FAILED_CURLY_START;      /*}*/
2747
2748     switch(read_subs(sub, nelem(sub), 1,
2749       &s, yield == NULL, TRUE, US"acl", resetok))
2750       {
2751       case 1: expand_string_message = US"too few arguments or bracketing "
2752         "error for acl";
2753       case 2:
2754       case 3: return NULL;
2755       }
2756
2757     if (yield)
2758       {
2759       int rc;
2760       *resetok = FALSE; /* eval_acl() might allocate; do not reclaim */
2761       switch(rc = eval_acl(sub, nelem(sub), &user_msg))
2762         {
2763         case OK:
2764           cond = TRUE;
2765         case FAIL:
2766           lookup_value = NULL;
2767           if (user_msg)
2768             lookup_value = string_copy(user_msg);
2769           *yield = cond == testfor;
2770           break;
2771
2772         case DEFER:
2773           f.expand_string_forcedfail = TRUE;
2774           /*FALLTHROUGH*/
2775         default:
2776           expand_string_message = string_sprintf("%s from acl \"%s\"",
2777             rc_names[rc], sub[0]);
2778           return NULL;
2779         }
2780       }
2781     return s;
2782     }
2783
2784
2785   /* saslauthd: does Cyrus saslauthd authentication. Four parameters are used:
2786
2787      ${if saslauthd {{username}{password}{service}{realm}}  {yes}{no}}
2788
2789   However, the last two are optional. That is why the whole set is enclosed
2790   in their own set of braces. */
2791
2792   case ECOND_SASLAUTHD:
2793 #ifndef CYRUS_SASLAUTHD_SOCKET
2794     goto COND_FAILED_NOT_COMPILED;
2795 #else
2796     {
2797     uschar *sub[4];
2798     while (isspace(*s)) s++;
2799     if (*s++ != '{') goto COND_FAILED_CURLY_START;      /* }-for-text-editors */
2800     switch(read_subs(sub, nelem(sub), 2, &s, yield == NULL, TRUE, US"saslauthd",
2801                     resetok))
2802       {
2803       case 1: expand_string_message = US"too few arguments or bracketing "
2804         "error for saslauthd";
2805       case 2:
2806       case 3: return NULL;
2807       }
2808     if (!sub[2]) sub[3] = NULL;  /* realm if no service */
2809     if (yield)
2810       {
2811       int rc = auth_call_saslauthd(sub[0], sub[1], sub[2], sub[3],
2812         &expand_string_message);
2813       if (rc == ERROR || rc == DEFER) return NULL;
2814       *yield = (rc == OK) == testfor;
2815       }
2816     return s;
2817     }
2818 #endif /* CYRUS_SASLAUTHD_SOCKET */
2819
2820
2821   /* symbolic operators for numeric and string comparison, and a number of
2822   other operators, all requiring two arguments.
2823
2824   crypteq:           encrypts plaintext and compares against an encrypted text,
2825                        using crypt(), crypt16(), MD5 or SHA-1
2826   inlist/inlisti:    checks if first argument is in the list of the second
2827   match:             does a regular expression match and sets up the numerical
2828                        variables if it succeeds
2829   match_address:     matches in an address list
2830   match_domain:      matches in a domain list
2831   match_ip:          matches a host list that is restricted to IP addresses
2832   match_local_part:  matches in a local part list
2833   */
2834
2835   case ECOND_MATCH_ADDRESS:
2836   case ECOND_MATCH_DOMAIN:
2837   case ECOND_MATCH_IP:
2838   case ECOND_MATCH_LOCAL_PART:
2839 #ifndef EXPAND_LISTMATCH_RHS
2840     sub2_honour_dollar = FALSE;
2841 #endif
2842     /* FALLTHROUGH */
2843
2844   case ECOND_CRYPTEQ:
2845   case ECOND_INLIST:
2846   case ECOND_INLISTI:
2847   case ECOND_MATCH:
2848
2849   case ECOND_NUM_L:     /* Numerical comparisons */
2850   case ECOND_NUM_LE:
2851   case ECOND_NUM_E:
2852   case ECOND_NUM_EE:
2853   case ECOND_NUM_G:
2854   case ECOND_NUM_GE:
2855
2856   case ECOND_STR_LT:    /* String comparisons */
2857   case ECOND_STR_LTI:
2858   case ECOND_STR_LE:
2859   case ECOND_STR_LEI:
2860   case ECOND_STR_EQ:
2861   case ECOND_STR_EQI:
2862   case ECOND_STR_GT:
2863   case ECOND_STR_GTI:
2864   case ECOND_STR_GE:
2865   case ECOND_STR_GEI:
2866
2867   for (int i = 0; i < 2; i++)
2868     {
2869     /* Sometimes, we don't expand substrings; too many insecure configurations
2870     created using match_address{}{} and friends, where the second param
2871     includes information from untrustworthy sources. */
2872     BOOL honour_dollar = TRUE;
2873     if ((i > 0) && !sub2_honour_dollar)
2874       honour_dollar = FALSE;
2875
2876     while (isspace(*s)) s++;
2877     if (*s != '{')
2878       {
2879       if (i == 0) goto COND_FAILED_CURLY_START;
2880       expand_string_message = string_sprintf("missing 2nd string in {} "
2881         "after \"%s\"", opname);
2882       return NULL;
2883       }
2884     if (!(sub[i] = expand_string_internal(s+1, TRUE, &s, yield == NULL,
2885         honour_dollar, resetok)))
2886       return NULL;
2887     DEBUG(D_expand) if (i == 1 && !sub2_honour_dollar && Ustrchr(sub[1], '$'))
2888       debug_printf_indent("WARNING: the second arg is NOT expanded,"
2889                         " for security reasons\n");
2890     if (*s++ != '}') goto COND_FAILED_CURLY_END;
2891
2892     /* Convert to numerical if required; we know that the names of all the
2893     conditions that compare numbers do not start with a letter. This just saves
2894     checking for them individually. */
2895
2896     if (!isalpha(opname[0]) && yield)
2897       if (sub[i][0] == 0)
2898         {
2899         num[i] = 0;
2900         DEBUG(D_expand)
2901           debug_printf_indent("empty string cast to zero for numerical comparison\n");
2902         }
2903       else
2904         {
2905         num[i] = expanded_string_integer(sub[i], FALSE);
2906         if (expand_string_message) return NULL;
2907         }
2908     }
2909
2910   /* Result not required */
2911
2912   if (!yield) return s;
2913
2914   /* Do an appropriate comparison */
2915
2916   switch(cond_type)
2917     {
2918     case ECOND_NUM_E:
2919     case ECOND_NUM_EE:
2920     tempcond = (num[0] == num[1]);
2921     break;
2922
2923     case ECOND_NUM_G:
2924     tempcond = (num[0] > num[1]);
2925     break;
2926
2927     case ECOND_NUM_GE:
2928     tempcond = (num[0] >= num[1]);
2929     break;
2930
2931     case ECOND_NUM_L:
2932     tempcond = (num[0] < num[1]);
2933     break;
2934
2935     case ECOND_NUM_LE:
2936     tempcond = (num[0] <= num[1]);
2937     break;
2938
2939     case ECOND_STR_LT:
2940     tempcond = (Ustrcmp(sub[0], sub[1]) < 0);
2941     break;
2942
2943     case ECOND_STR_LTI:
2944     tempcond = (strcmpic(sub[0], sub[1]) < 0);
2945     break;
2946
2947     case ECOND_STR_LE:
2948     tempcond = (Ustrcmp(sub[0], sub[1]) <= 0);
2949     break;
2950
2951     case ECOND_STR_LEI:
2952     tempcond = (strcmpic(sub[0], sub[1]) <= 0);
2953     break;
2954
2955     case ECOND_STR_EQ:
2956     tempcond = (Ustrcmp(sub[0], sub[1]) == 0);
2957     break;
2958
2959     case ECOND_STR_EQI:
2960     tempcond = (strcmpic(sub[0], sub[1]) == 0);
2961     break;
2962
2963     case ECOND_STR_GT:
2964     tempcond = (Ustrcmp(sub[0], sub[1]) > 0);
2965     break;
2966
2967     case ECOND_STR_GTI:
2968     tempcond = (strcmpic(sub[0], sub[1]) > 0);
2969     break;
2970
2971     case ECOND_STR_GE:
2972     tempcond = (Ustrcmp(sub[0], sub[1]) >= 0);
2973     break;
2974
2975     case ECOND_STR_GEI:
2976     tempcond = (strcmpic(sub[0], sub[1]) >= 0);
2977     break;
2978
2979     case ECOND_MATCH:   /* Regular expression match */
2980     if (!(re = pcre_compile(CS sub[1], PCRE_COPT, CCSS &rerror,
2981                             &roffset, NULL)))
2982       {
2983       expand_string_message = string_sprintf("regular expression error in "
2984         "\"%s\": %s at offset %d", sub[1], rerror, roffset);
2985       return NULL;
2986       }
2987     tempcond = regex_match_and_setup(re, sub[0], 0, -1);
2988     break;
2989
2990     case ECOND_MATCH_ADDRESS:  /* Match in an address list */
2991     rc = match_address_list(sub[0], TRUE, FALSE, &(sub[1]), NULL, -1, 0, NULL);
2992     goto MATCHED_SOMETHING;
2993
2994     case ECOND_MATCH_DOMAIN:   /* Match in a domain list */
2995     rc = match_isinlist(sub[0], &(sub[1]), 0, &domainlist_anchor, NULL,
2996       MCL_DOMAIN + MCL_NOEXPAND, TRUE, NULL);
2997     goto MATCHED_SOMETHING;
2998
2999     case ECOND_MATCH_IP:       /* Match IP address in a host list */
3000     if (sub[0][0] != 0 && string_is_ip_address(sub[0], NULL) == 0)
3001       {
3002       expand_string_message = string_sprintf("\"%s\" is not an IP address",
3003         sub[0]);
3004       return NULL;
3005       }
3006     else
3007       {
3008       unsigned int *nullcache = NULL;
3009       check_host_block cb;
3010
3011       cb.host_name = US"";
3012       cb.host_address = sub[0];
3013
3014       /* If the host address starts off ::ffff: it is an IPv6 address in
3015       IPv4-compatible mode. Find the IPv4 part for checking against IPv4
3016       addresses. */
3017
3018       cb.host_ipv4 = (Ustrncmp(cb.host_address, "::ffff:", 7) == 0)?
3019         cb.host_address + 7 : cb.host_address;
3020
3021       rc = match_check_list(
3022              &sub[1],                   /* the list */
3023              0,                         /* separator character */
3024              &hostlist_anchor,          /* anchor pointer */
3025              &nullcache,                /* cache pointer */
3026              check_host,                /* function for testing */
3027              &cb,                       /* argument for function */
3028              MCL_HOST,                  /* type of check */
3029              sub[0],                    /* text for debugging */
3030              NULL);                     /* where to pass back data */
3031       }
3032     goto MATCHED_SOMETHING;
3033
3034     case ECOND_MATCH_LOCAL_PART:
3035     rc = match_isinlist(sub[0], &(sub[1]), 0, &localpartlist_anchor, NULL,
3036       MCL_LOCALPART + MCL_NOEXPAND, TRUE, NULL);
3037     /* Fall through */
3038     /* VVVVVVVVVVVV */
3039     MATCHED_SOMETHING:
3040     switch(rc)
3041       {
3042       case OK:
3043       tempcond = TRUE;
3044       break;
3045
3046       case FAIL:
3047       tempcond = FALSE;
3048       break;
3049
3050       case DEFER:
3051       expand_string_message = string_sprintf("unable to complete match "
3052         "against \"%s\": %s", sub[1], search_error_message);
3053       return NULL;
3054       }
3055
3056     break;
3057
3058     /* Various "encrypted" comparisons. If the second string starts with
3059     "{" then an encryption type is given. Default to crypt() or crypt16()
3060     (build-time choice). */
3061     /* }-for-text-editors */
3062
3063     case ECOND_CRYPTEQ:
3064     #ifndef SUPPORT_CRYPTEQ
3065     goto COND_FAILED_NOT_COMPILED;
3066     #else
3067     if (strncmpic(sub[1], US"{md5}", 5) == 0)
3068       {
3069       int sublen = Ustrlen(sub[1]+5);
3070       md5 base;
3071       uschar digest[16];
3072
3073       md5_start(&base);
3074       md5_end(&base, sub[0], Ustrlen(sub[0]), digest);
3075
3076       /* If the length that we are comparing against is 24, the MD5 digest
3077       is expressed as a base64 string. This is the way LDAP does it. However,
3078       some other software uses a straightforward hex representation. We assume
3079       this if the length is 32. Other lengths fail. */
3080
3081       if (sublen == 24)
3082         {
3083         uschar *coded = b64encode(CUS digest, 16);
3084         DEBUG(D_auth) debug_printf("crypteq: using MD5+B64 hashing\n"
3085           "  subject=%s\n  crypted=%s\n", coded, sub[1]+5);
3086         tempcond = (Ustrcmp(coded, sub[1]+5) == 0);
3087         }
3088       else if (sublen == 32)
3089         {
3090         uschar coded[36];
3091         for (int i = 0; i < 16; i++) sprintf(CS (coded+2*i), "%02X", digest[i]);
3092         coded[32] = 0;
3093         DEBUG(D_auth) debug_printf("crypteq: using MD5+hex hashing\n"
3094           "  subject=%s\n  crypted=%s\n", coded, sub[1]+5);
3095         tempcond = (strcmpic(coded, sub[1]+5) == 0);
3096         }
3097       else
3098         {
3099         DEBUG(D_auth) debug_printf("crypteq: length for MD5 not 24 or 32: "
3100           "fail\n  crypted=%s\n", sub[1]+5);
3101         tempcond = FALSE;
3102         }
3103       }
3104
3105     else if (strncmpic(sub[1], US"{sha1}", 6) == 0)
3106       {
3107       int sublen = Ustrlen(sub[1]+6);
3108       hctx h;
3109       uschar digest[20];
3110
3111       sha1_start(&h);
3112       sha1_end(&h, sub[0], Ustrlen(sub[0]), digest);
3113
3114       /* If the length that we are comparing against is 28, assume the SHA1
3115       digest is expressed as a base64 string. If the length is 40, assume a
3116       straightforward hex representation. Other lengths fail. */
3117
3118       if (sublen == 28)
3119         {
3120         uschar *coded = b64encode(CUS digest, 20);
3121         DEBUG(D_auth) debug_printf("crypteq: using SHA1+B64 hashing\n"
3122           "  subject=%s\n  crypted=%s\n", coded, sub[1]+6);
3123         tempcond = (Ustrcmp(coded, sub[1]+6) == 0);
3124         }
3125       else if (sublen == 40)
3126         {
3127         uschar coded[44];
3128         for (int i = 0; i < 20; i++) sprintf(CS (coded+2*i), "%02X", digest[i]);
3129         coded[40] = 0;
3130         DEBUG(D_auth) debug_printf("crypteq: using SHA1+hex hashing\n"
3131           "  subject=%s\n  crypted=%s\n", coded, sub[1]+6);
3132         tempcond = (strcmpic(coded, sub[1]+6) == 0);
3133         }
3134       else
3135         {
3136         DEBUG(D_auth) debug_printf("crypteq: length for SHA-1 not 28 or 40: "
3137           "fail\n  crypted=%s\n", sub[1]+6);
3138         tempcond = FALSE;
3139         }
3140       }
3141
3142     else   /* {crypt} or {crypt16} and non-{ at start */
3143            /* }-for-text-editors */
3144       {
3145       int which = 0;
3146       uschar *coded;
3147
3148       if (strncmpic(sub[1], US"{crypt}", 7) == 0)
3149         {
3150         sub[1] += 7;
3151         which = 1;
3152         }
3153       else if (strncmpic(sub[1], US"{crypt16}", 9) == 0)
3154         {
3155         sub[1] += 9;
3156         which = 2;
3157         }
3158       else if (sub[1][0] == '{')                /* }-for-text-editors */
3159         {
3160         expand_string_message = string_sprintf("unknown encryption mechanism "
3161           "in \"%s\"", sub[1]);
3162         return NULL;
3163         }
3164
3165       switch(which)
3166         {
3167         case 0:  coded = US DEFAULT_CRYPT(CS sub[0], CS sub[1]); break;
3168         case 1:  coded = US crypt(CS sub[0], CS sub[1]); break;
3169         default: coded = US crypt16(CS sub[0], CS sub[1]); break;
3170         }
3171
3172       #define STR(s) # s
3173       #define XSTR(s) STR(s)
3174       DEBUG(D_auth) debug_printf("crypteq: using %s()\n"
3175         "  subject=%s\n  crypted=%s\n",
3176         which == 0 ? XSTR(DEFAULT_CRYPT) : which == 1 ? "crypt" : "crypt16",
3177         coded, sub[1]);
3178       #undef STR
3179       #undef XSTR
3180
3181       /* If the encrypted string contains fewer than two characters (for the
3182       salt), force failure. Otherwise we get false positives: with an empty
3183       string the yield of crypt() is an empty string! */
3184
3185       if (coded)
3186         tempcond = Ustrlen(sub[1]) < 2 ? FALSE : Ustrcmp(coded, sub[1]) == 0;
3187       else if (errno == EINVAL)
3188         tempcond = FALSE;
3189       else
3190         {
3191         expand_string_message = string_sprintf("crypt error: %s\n",
3192           US strerror(errno));
3193         return NULL;
3194         }
3195       }
3196     break;
3197     #endif  /* SUPPORT_CRYPTEQ */
3198
3199     case ECOND_INLIST:
3200     case ECOND_INLISTI:
3201       {
3202       const uschar * list = sub[1];
3203       int sep = 0;
3204       uschar *save_iterate_item = iterate_item;
3205       int (*compare)(const uschar *, const uschar *);
3206
3207       DEBUG(D_expand) debug_printf_indent("condition: %s  item: %s\n", opname, sub[0]);
3208
3209       tempcond = FALSE;
3210       compare = cond_type == ECOND_INLISTI
3211         ? strcmpic : (int (*)(const uschar *, const uschar *)) strcmp;
3212
3213       while ((iterate_item = string_nextinlist(&list, &sep, NULL, 0)))
3214         {
3215         DEBUG(D_expand) debug_printf_indent(" compare %s\n", iterate_item);
3216         if (compare(sub[0], iterate_item) == 0)
3217           {
3218           tempcond = TRUE;
3219           break;
3220           }
3221         }
3222       iterate_item = save_iterate_item;
3223       }
3224
3225     }   /* Switch for comparison conditions */
3226
3227   *yield = tempcond == testfor;
3228   return s;    /* End of comparison conditions */
3229
3230
3231   /* and/or: computes logical and/or of several conditions */
3232
3233   case ECOND_AND:
3234   case ECOND_OR:
3235   subcondptr = (yield == NULL) ? NULL : &tempcond;
3236   combined_cond = (cond_type == ECOND_AND);
3237
3238   while (isspace(*s)) s++;
3239   if (*s++ != '{') goto COND_FAILED_CURLY_START;        /* }-for-text-editors */
3240
3241   for (;;)
3242     {
3243     while (isspace(*s)) s++;
3244     /* {-for-text-editors */
3245     if (*s == '}') break;
3246     if (*s != '{')                                      /* }-for-text-editors */
3247       {
3248       expand_string_message = string_sprintf("each subcondition "
3249         "inside an \"%s{...}\" condition must be in its own {}", opname);
3250       return NULL;
3251       }
3252
3253     if (!(s = eval_condition(s+1, resetok, subcondptr)))
3254       {
3255       expand_string_message = string_sprintf("%s inside \"%s{...}\" condition",
3256         expand_string_message, opname);
3257       return NULL;
3258       }
3259     while (isspace(*s)) s++;
3260
3261     /* {-for-text-editors */
3262     if (*s++ != '}')
3263       {
3264       /* {-for-text-editors */
3265       expand_string_message = string_sprintf("missing } at end of condition "
3266         "inside \"%s\" group", opname);
3267       return NULL;
3268       }
3269
3270     if (yield)
3271       if (cond_type == ECOND_AND)
3272         {
3273         combined_cond &= tempcond;
3274         if (!combined_cond) subcondptr = NULL;  /* once false, don't */
3275         }                                       /* evaluate any more */
3276       else
3277         {
3278         combined_cond |= tempcond;
3279         if (combined_cond) subcondptr = NULL;   /* once true, don't */
3280         }                                       /* evaluate any more */
3281     }
3282
3283   if (yield) *yield = (combined_cond == testfor);
3284   return ++s;
3285
3286
3287   /* forall/forany: iterates a condition with different values */
3288
3289   case ECOND_FORALL:      is_forany = FALSE;  is_json = FALSE; is_jsons = FALSE; goto FORMANY;
3290   case ECOND_FORANY:      is_forany = TRUE;   is_json = FALSE; is_jsons = FALSE; goto FORMANY;
3291   case ECOND_FORALL_JSON: is_forany = FALSE;  is_json = TRUE;  is_jsons = FALSE; goto FORMANY;
3292   case ECOND_FORANY_JSON: is_forany = TRUE;   is_json = TRUE;  is_jsons = FALSE; goto FORMANY;
3293   case ECOND_FORALL_JSONS: is_forany = FALSE; is_json = TRUE;  is_jsons = TRUE;  goto FORMANY;
3294   case ECOND_FORANY_JSONS: is_forany = TRUE;  is_json = TRUE;  is_jsons = TRUE;  goto FORMANY;
3295
3296   FORMANY:
3297     {
3298     const uschar * list;
3299     int sep = 0;
3300     uschar *save_iterate_item = iterate_item;
3301
3302     DEBUG(D_expand) debug_printf_indent("condition: %s\n", opname);
3303
3304     while (isspace(*s)) s++;
3305     if (*s++ != '{') goto COND_FAILED_CURLY_START;      /* }-for-text-editors */
3306     if (!(sub[0] = expand_string_internal(s, TRUE, &s, yield == NULL, TRUE, resetok)))
3307       return NULL;
3308     /* {-for-text-editors */
3309     if (*s++ != '}') goto COND_FAILED_CURLY_END;
3310
3311     while (isspace(*s)) s++;
3312     if (*s++ != '{') goto COND_FAILED_CURLY_START;      /* }-for-text-editors */
3313
3314     sub[1] = s;
3315
3316     /* Call eval_condition once, with result discarded (as if scanning a
3317     "false" part). This allows us to find the end of the condition, because if
3318     the list it empty, we won't actually evaluate the condition for real. */
3319
3320     if (!(s = eval_condition(sub[1], resetok, NULL)))
3321       {
3322       expand_string_message = string_sprintf("%s inside \"%s\" condition",
3323         expand_string_message, opname);
3324       return NULL;
3325       }
3326     while (isspace(*s)) s++;
3327
3328     /* {-for-text-editors */
3329     if (*s++ != '}')
3330       {
3331       /* {-for-text-editors */
3332       expand_string_message = string_sprintf("missing } at end of condition "
3333         "inside \"%s\"", opname);
3334       return NULL;
3335       }
3336
3337     if (yield) *yield = !testfor;
3338     list = sub[0];
3339     if (is_json) list = dewrap(string_copy(list), US"[]");
3340     while ((iterate_item = is_json
3341       ? json_nextinlist(&list) : string_nextinlist(&list, &sep, NULL, 0)))
3342       {
3343       if (is_jsons)
3344         if (!(iterate_item = dewrap(iterate_item, US"\"\"")))
3345           {
3346           expand_string_message =
3347             string_sprintf("%s wrapping string result for extract jsons",
3348               expand_string_message);
3349           iterate_item = save_iterate_item;
3350           return NULL;
3351           }
3352
3353       DEBUG(D_expand) debug_printf_indent("%s: $item = \"%s\"\n", opname, iterate_item);
3354       if (!eval_condition(sub[1], resetok, &tempcond))
3355         {
3356         expand_string_message = string_sprintf("%s inside \"%s\" condition",
3357           expand_string_message, opname);
3358         iterate_item = save_iterate_item;
3359         return NULL;
3360         }
3361       DEBUG(D_expand) debug_printf_indent("%s: condition evaluated to %s\n", opname,
3362         tempcond? "true":"false");
3363
3364       if (yield) *yield = (tempcond == testfor);
3365       if (tempcond == is_forany) break;
3366       }
3367
3368     iterate_item = save_iterate_item;
3369     return s;
3370     }
3371
3372
3373   /* The bool{} expansion condition maps a string to boolean.
3374   The values supported should match those supported by the ACL condition
3375   (acl.c, ACLC_CONDITION) so that we keep to a minimum the different ideas
3376   of true/false.  Note that Router "condition" rules have a different
3377   interpretation, where general data can be used and only a few values
3378   map to FALSE.
3379   Note that readconf.c boolean matching, for boolean configuration options,
3380   only matches true/yes/false/no.
3381   The bool_lax{} condition matches the Router logic, which is much more
3382   liberal. */
3383   case ECOND_BOOL:
3384   case ECOND_BOOL_LAX:
3385     {
3386     uschar *sub_arg[1];
3387     uschar *t, *t2;
3388     uschar *ourname;
3389     size_t len;
3390     BOOL boolvalue = FALSE;
3391     while (isspace(*s)) s++;
3392     if (*s != '{') goto COND_FAILED_CURLY_START;        /* }-for-text-editors */
3393     ourname = cond_type == ECOND_BOOL_LAX ? US"bool_lax" : US"bool";
3394     switch(read_subs(sub_arg, 1, 1, &s, yield == NULL, FALSE, ourname, resetok))
3395       {
3396       case 1: expand_string_message = string_sprintf(
3397                   "too few arguments or bracketing error for %s",
3398                   ourname);
3399       /*FALLTHROUGH*/
3400       case 2:
3401       case 3: return NULL;
3402       }
3403     t = sub_arg[0];
3404     while (isspace(*t)) t++;
3405     len = Ustrlen(t);
3406     if (len)
3407       {
3408       /* trailing whitespace: seems like a good idea to ignore it too */
3409       t2 = t + len - 1;
3410       while (isspace(*t2)) t2--;
3411       if (t2 != (t + len))
3412         {
3413         *++t2 = '\0';
3414         len = t2 - t;
3415         }
3416       }
3417     DEBUG(D_expand)
3418       debug_printf_indent("considering %s: %s\n", ourname, len ? t : US"<empty>");
3419     /* logic for the lax case from expand_check_condition(), which also does
3420     expands, and the logic is both short and stable enough that there should
3421     be no maintenance burden from replicating it. */
3422     if (len == 0)
3423       boolvalue = FALSE;
3424     else if (*t == '-'
3425              ? Ustrspn(t+1, "0123456789") == len-1
3426              : Ustrspn(t,   "0123456789") == len)
3427       {
3428       boolvalue = (Uatoi(t) == 0) ? FALSE : TRUE;
3429       /* expand_check_condition only does a literal string "0" check */
3430       if ((cond_type == ECOND_BOOL_LAX) && (len > 1))
3431         boolvalue = TRUE;
3432       }
3433     else if (strcmpic(t, US"true") == 0 || strcmpic(t, US"yes") == 0)
3434       boolvalue = TRUE;
3435     else if (strcmpic(t, US"false") == 0 || strcmpic(t, US"no") == 0)
3436       boolvalue = FALSE;
3437     else if (cond_type == ECOND_BOOL_LAX)
3438       boolvalue = TRUE;
3439     else
3440       {
3441       expand_string_message = string_sprintf("unrecognised boolean "
3442        "value \"%s\"", t);
3443       return NULL;
3444       }
3445     DEBUG(D_expand) debug_printf_indent("%s: condition evaluated to %s\n", ourname,
3446         boolvalue? "true":"false");
3447     if (yield) *yield = (boolvalue == testfor);
3448     return s;
3449     }
3450
3451 #ifdef EXPERIMENTAL_SRS_NATIVE
3452   case ECOND_INBOUND_SRS:
3453     /* ${if inbound_srs {local_part}{secret}  {yes}{no}} */
3454     {
3455     uschar * sub[2];
3456     const pcre * re;
3457     int ovec[3*(4+1)];
3458     int n;
3459     uschar cksum[4];
3460     BOOL boolvalue = FALSE;
3461
3462     switch(read_subs(sub, 2, 2, CUSS &s, yield == NULL, FALSE, US"inbound_srs", resetok))
3463       {
3464       case 1: expand_string_message = US"too few arguments or bracketing "
3465         "error for inbound_srs";
3466       case 2:
3467       case 3: return NULL;
3468       }
3469
3470     /* Match the given local_part against the SRS-encoded pattern */
3471
3472     re = regex_must_compile(US"^(?i)SRS0=([^=]+)=([A-Z2-7]+)=([^=]*)=(.*)$",
3473                             TRUE, FALSE);
3474     if (pcre_exec(re, NULL, CS sub[0], Ustrlen(sub[0]), 0, PCRE_EOPT,
3475                   ovec, nelem(ovec)) < 0)
3476       {
3477       DEBUG(D_expand) debug_printf("no match for SRS'd local-part pattern\n");
3478       goto srs_result;
3479       }
3480
3481     /* Side-effect: record the decoded recipient */
3482
3483     srs_recipient = string_sprintf("%.*S@%.*S",                 /* lowercased */
3484                       ovec[9]-ovec[8], sub[0] + ovec[8],        /* substring 4 */
3485                       ovec[7]-ovec[6], sub[0] + ovec[6]);       /* substring 3 */
3486
3487     /* If a zero-length secret was given, we're done.  Otherwise carry on
3488     and validate the given SRS local_part againt our secret. */
3489
3490     if (!*sub[1])
3491       {
3492       boolvalue = TRUE;
3493       goto srs_result;
3494       }
3495
3496     /* check the timestamp */
3497       {
3498       struct timeval now;
3499       uschar * ss = sub[0] + ovec[4];   /* substring 2, the timestamp */
3500       long d;
3501
3502       gettimeofday(&now, NULL);
3503       now.tv_sec /= 86400;              /* days since epoch */
3504
3505       /* Decode substring 2 from base32 to a number */
3506
3507       for (d = 0, n = ovec[5]-ovec[4]; n; n--)
3508         {
3509         uschar * t = Ustrchr(base32_chars, *ss++);
3510         d = d * 32 + (t - base32_chars);
3511         }
3512
3513       if (((now.tv_sec - d) & 0x3ff) > 10)      /* days since SRS generated */
3514         {
3515         DEBUG(D_expand) debug_printf("SRS too old\n");
3516         goto srs_result;
3517         }
3518       }
3519
3520     /* check length of substring 1, the offered checksum */
3521
3522     if (ovec[3]-ovec[2] != 4)
3523       {
3524       DEBUG(D_expand) debug_printf("SRS checksum wrong size\n");
3525       goto srs_result;
3526       }
3527
3528     /* Hash the address with our secret, and compare that computed checksum
3529     with the one extracted from the arg */
3530
3531     hmac_md5(sub[1], srs_recipient, cksum, sizeof(cksum));
3532     if (Ustrncmp(cksum, sub[0] + ovec[2], 4) != 0)
3533       {
3534       DEBUG(D_expand) debug_printf("SRS checksum mismatch\n");
3535       goto srs_result;
3536       }
3537     boolvalue = TRUE;
3538
3539 srs_result:
3540     if (yield) *yield = (boolvalue == testfor);
3541     return s;
3542     }
3543 #endif /*EXPERIMENTAL_SRS_NATIVE*/
3544
3545   /* Unknown condition */
3546
3547   default:
3548     if (!expand_string_message || !*expand_string_message)
3549       expand_string_message = string_sprintf("unknown condition \"%s\"", opname);
3550     return NULL;
3551   }   /* End switch on condition type */
3552
3553 /* Missing braces at start and end of data */
3554
3555 COND_FAILED_CURLY_START:
3556 expand_string_message = string_sprintf("missing { after \"%s\"", opname);
3557 return NULL;
3558
3559 COND_FAILED_CURLY_END:
3560 expand_string_message = string_sprintf("missing } at end of \"%s\" condition",
3561   opname);
3562 return NULL;
3563
3564 /* A condition requires code that is not compiled */
3565
3566 #if !defined(SUPPORT_PAM) || !defined(RADIUS_CONFIG_FILE) || \
3567     !defined(LOOKUP_LDAP) || !defined(CYRUS_PWCHECK_SOCKET) || \
3568     !defined(SUPPORT_CRYPTEQ) || !defined(CYRUS_SASLAUTHD_SOCKET)
3569 COND_FAILED_NOT_COMPILED:
3570 expand_string_message = string_sprintf("support for \"%s\" not compiled",
3571   opname);
3572 return NULL;
3573 #endif
3574 }
3575
3576
3577
3578
3579 /*************************************************
3580 *          Save numerical variables              *
3581 *************************************************/
3582
3583 /* This function is called from items such as "if" that want to preserve and
3584 restore the numbered variables.
3585
3586 Arguments:
3587   save_expand_string    points to an array of pointers to set
3588   save_expand_nlength   points to an array of ints for the lengths
3589
3590 Returns:                the value of expand max to save
3591 */
3592
3593 static int
3594 save_expand_strings(uschar **save_expand_nstring, int *save_expand_nlength)
3595 {
3596 for (int i = 0; i <= expand_nmax; i++)
3597   {
3598   save_expand_nstring[i] = expand_nstring[i];
3599   save_expand_nlength[i] = expand_nlength[i];
3600   }
3601 return expand_nmax;
3602 }
3603
3604
3605
3606 /*************************************************
3607 *           Restore numerical variables          *
3608 *************************************************/
3609
3610 /* This function restored saved values of numerical strings.
3611
3612 Arguments:
3613   save_expand_nmax      the number of strings to restore
3614   save_expand_string    points to an array of pointers
3615   save_expand_nlength   points to an array of ints
3616
3617 Returns:                nothing
3618 */
3619
3620 static void
3621 restore_expand_strings(int save_expand_nmax, uschar **save_expand_nstring,
3622   int *save_expand_nlength)
3623 {
3624 expand_nmax = save_expand_nmax;
3625 for (int i = 0; i <= expand_nmax; i++)
3626   {
3627   expand_nstring[i] = save_expand_nstring[i];
3628   expand_nlength[i] = save_expand_nlength[i];
3629   }
3630 }
3631
3632
3633
3634
3635
3636 /*************************************************
3637 *            Handle yes/no substrings            *
3638 *************************************************/
3639
3640 /* This function is used by ${if}, ${lookup} and ${extract} to handle the
3641 alternative substrings that depend on whether or not the condition was true,
3642 or the lookup or extraction succeeded. The substrings always have to be
3643 expanded, to check their syntax, but "skipping" is set when the result is not
3644 needed - this avoids unnecessary nested lookups.
3645
3646 Arguments:
3647   skipping       TRUE if we were skipping when this item was reached
3648   yes            TRUE if the first string is to be used, else use the second
3649   save_lookup    a value to put back into lookup_value before the 2nd expansion
3650   sptr           points to the input string pointer
3651   yieldptr       points to the output growable-string pointer
3652   type           "lookup", "if", "extract", "run", "env", "listextract" or
3653                  "certextract" for error message
3654   resetok        if not NULL, pointer to flag - write FALSE if unsafe to reset
3655                 the store.
3656
3657 Returns:         0 OK; lookup_value has been reset to save_lookup
3658                  1 expansion failed
3659                  2 expansion failed because of bracketing error
3660 */
3661
3662 static int
3663 process_yesno(BOOL skipping, BOOL yes, uschar *save_lookup, const uschar **sptr,
3664   gstring ** yieldptr, uschar *type, BOOL *resetok)
3665 {
3666 int rc = 0;
3667 const uschar *s = *sptr;    /* Local value */
3668 uschar *sub1, *sub2;
3669 const uschar * errwhere;
3670
3671 /* If there are no following strings, we substitute the contents of $value for
3672 lookups and for extractions in the success case. For the ${if item, the string
3673 "true" is substituted. In the fail case, nothing is substituted for all three
3674 items. */
3675
3676 while (isspace(*s)) s++;
3677 if (*s == '}')
3678   {
3679   if (type[0] == 'i')
3680     {
3681     if (yes && !skipping)
3682       *yieldptr = string_catn(*yieldptr, US"true", 4);
3683     }
3684   else
3685     {
3686     if (yes && lookup_value && !skipping)
3687       *yieldptr = string_cat(*yieldptr, lookup_value);
3688     lookup_value = save_lookup;
3689     }
3690   s++;
3691   goto RETURN;
3692   }
3693
3694 /* The first following string must be braced. */
3695
3696 if (*s++ != '{')
3697   {
3698   errwhere = US"'yes' part did not start with '{'";
3699   goto FAILED_CURLY;
3700   }
3701
3702 /* Expand the first substring. Forced failures are noticed only if we actually
3703 want this string. Set skipping in the call in the fail case (this will always
3704 be the case if we were already skipping). */
3705
3706 sub1 = expand_string_internal(s, TRUE, &s, !yes, TRUE, resetok);
3707 if (sub1 == NULL && (yes || !f.expand_string_forcedfail)) goto FAILED;
3708 f.expand_string_forcedfail = FALSE;
3709 if (*s++ != '}')
3710   {
3711   errwhere = US"'yes' part did not end with '}'";
3712   goto FAILED_CURLY;
3713   }
3714
3715 /* If we want the first string, add it to the output */
3716
3717 if (yes)
3718   *yieldptr = string_cat(*yieldptr, sub1);
3719
3720 /* If this is called from a lookup/env or a (cert)extract, we want to restore
3721 $value to what it was at the start of the item, so that it has this value
3722 during the second string expansion. For the call from "if" or "run" to this
3723 function, save_lookup is set to lookup_value, so that this statement does
3724 nothing. */
3725
3726 lookup_value = save_lookup;
3727
3728 /* There now follows either another substring, or "fail", or nothing. This
3729 time, forced failures are noticed only if we want the second string. We must
3730 set skipping in the nested call if we don't want this string, or if we were
3731 already skipping. */
3732
3733 while (isspace(*s)) s++;
3734 if (*s == '{')
3735   {
3736   sub2 = expand_string_internal(s+1, TRUE, &s, yes || skipping, TRUE, resetok);
3737   if (sub2 == NULL && (!yes || !f.expand_string_forcedfail)) goto FAILED;
3738   f.expand_string_forcedfail = FALSE;
3739   if (*s++ != '}')
3740     {
3741     errwhere = US"'no' part did not start with '{'";
3742     goto FAILED_CURLY;
3743     }
3744
3745   /* If we want the second string, add it to the output */
3746
3747   if (!yes)
3748     *yieldptr = string_cat(*yieldptr, sub2);
3749   }
3750
3751 /* If there is no second string, but the word "fail" is present when the use of
3752 the second string is wanted, set a flag indicating it was a forced failure
3753 rather than a syntactic error. Swallow the terminating } in case this is nested
3754 inside another lookup or if or extract. */
3755
3756 else if (*s != '}')
3757   {
3758   uschar name[256];
3759   /* deconst cast ok here as source is s anyway */
3760   s = US read_name(name, sizeof(name), s, US"_");
3761   if (Ustrcmp(name, "fail") == 0)
3762     {
3763     if (!yes && !skipping)
3764       {
3765       while (isspace(*s)) s++;
3766       if (*s++ != '}')
3767         {
3768         errwhere = US"did not close with '}' after forcedfail";
3769         goto FAILED_CURLY;
3770         }
3771       expand_string_message =
3772         string_sprintf("\"%s\" failed and \"fail\" requested", type);
3773       f.expand_string_forcedfail = TRUE;
3774       goto FAILED;
3775       }
3776     }
3777   else
3778     {
3779     expand_string_message =
3780       string_sprintf("syntax error in \"%s\" item - \"fail\" expected", type);
3781     goto FAILED;
3782     }
3783   }
3784
3785 /* All we have to do now is to check on the final closing brace. */
3786
3787 while (isspace(*s)) s++;
3788 if (*s++ != '}')
3789   {
3790   errwhere = US"did not close with '}'";
3791   goto FAILED_CURLY;
3792   }
3793
3794
3795 RETURN:
3796 /* Update the input pointer value before returning */
3797 *sptr = s;
3798 return rc;
3799
3800 FAILED_CURLY:
3801   /* Get here if there is a bracketing failure */
3802   expand_string_message = string_sprintf(
3803     "curly-bracket problem in conditional yes/no parsing: %s\n"
3804     " remaining string is '%s'", errwhere, --s);
3805   rc = 2;
3806   goto RETURN;
3807
3808 FAILED:
3809   /* Get here for other failures */
3810   rc = 1;
3811   goto RETURN;
3812 }
3813
3814
3815
3816
3817 /********************************************************
3818 * prvs: Get last three digits of days since Jan 1, 1970 *
3819 ********************************************************/
3820
3821 /* This is needed to implement the "prvs" BATV reverse
3822    path signing scheme
3823
3824 Argument: integer "days" offset to add or substract to
3825           or from the current number of days.
3826
3827 Returns:  pointer to string containing the last three
3828           digits of the number of days since Jan 1, 1970,
3829           modified by the offset argument, NULL if there
3830           was an error in the conversion.
3831
3832 */
3833
3834 static uschar *
3835 prvs_daystamp(int day_offset)
3836 {
3837 uschar *days = store_get(32, FALSE);         /* Need at least 24 for cases */
3838 (void)string_format(days, 32, TIME_T_FMT,    /* where TIME_T_FMT is %lld */
3839   (time(NULL) + day_offset*86400)/86400);
3840 return (Ustrlen(days) >= 3) ? &days[Ustrlen(days)-3] : US"100";
3841 }
3842
3843
3844
3845 /********************************************************
3846 *   prvs: perform HMAC-SHA1 computation of prvs bits    *
3847 ********************************************************/
3848
3849 /* This is needed to implement the "prvs" BATV reverse
3850    path signing scheme
3851
3852 Arguments:
3853   address RFC2821 Address to use
3854       key The key to use (must be less than 64 characters
3855           in size)
3856   key_num Single-digit key number to use. Defaults to
3857           '0' when NULL.
3858
3859 Returns:  pointer to string containing the first three
3860           bytes of the final hash in hex format, NULL if
3861           there was an error in the process.
3862 */
3863
3864 static uschar *
3865 prvs_hmac_sha1(uschar *address, uschar *key, uschar *key_num, uschar *daystamp)
3866 {
3867 gstring * hash_source;
3868 uschar * p;
3869 hctx h;
3870 uschar innerhash[20];
3871 uschar finalhash[20];
3872 uschar innerkey[64];
3873 uschar outerkey[64];
3874 uschar *finalhash_hex;
3875
3876 if (!key_num)
3877   key_num = US"0";
3878
3879 if (Ustrlen(key) > 64)
3880   return NULL;
3881
3882 hash_source = string_catn(NULL, key_num, 1);
3883 hash_source = string_catn(hash_source, daystamp, 3);
3884 hash_source = string_cat(hash_source, address);
3885 (void) string_from_gstring(hash_source);
3886
3887 DEBUG(D_expand)
3888   debug_printf_indent("prvs: hash source is '%s'\n", hash_source->s);
3889
3890 memset(innerkey, 0x36, 64);
3891 memset(outerkey, 0x5c, 64);
3892
3893 for (int i = 0; i < Ustrlen(key); i++)
3894   {
3895   innerkey[i] ^= key[i];
3896   outerkey[i] ^= key[i];
3897   }
3898
3899 chash_start(HMAC_SHA1, &h);
3900 chash_mid(HMAC_SHA1, &h, innerkey);
3901 chash_end(HMAC_SHA1, &h, hash_source->s, hash_source->ptr, innerhash);
3902
3903 chash_start(HMAC_SHA1, &h);
3904 chash_mid(HMAC_SHA1, &h, outerkey);
3905 chash_end(HMAC_SHA1, &h, innerhash, 20, finalhash);
3906
3907 /* Hashing is deemed sufficient to de-taint any input data */
3908
3909 p = finalhash_hex = store_get(40, FALSE);
3910 for (int i = 0; i < 3; i++)
3911   {
3912   *p++ = hex_digits[(finalhash[i] & 0xf0) >> 4];
3913   *p++ = hex_digits[finalhash[i] & 0x0f];
3914   }
3915 *p = '\0';
3916
3917 return finalhash_hex;
3918 }
3919
3920
3921
3922
3923 /*************************************************
3924 *        Join a file onto the output string      *
3925 *************************************************/
3926
3927 /* This is used for readfile/readsock and after a run expansion.
3928 It joins the contents of a file onto the output string, globally replacing
3929 newlines with a given string (optionally).
3930
3931 Arguments:
3932   f            the FILE
3933   yield        pointer to the expandable string struct
3934   eol          newline replacement string, or NULL
3935
3936 Returns:       new pointer for expandable string, terminated if non-null
3937 */
3938
3939 static gstring *
3940 cat_file(FILE *f, gstring *yield, uschar *eol)
3941 {
3942 uschar buffer[1024];
3943
3944 while (Ufgets(buffer, sizeof(buffer), f))
3945   {
3946   int len = Ustrlen(buffer);
3947   if (eol && buffer[len-1] == '\n') len--;
3948   yield = string_catn(yield, buffer, len);
3949   if (eol && buffer[len])
3950     yield = string_cat(yield, eol);
3951   }
3952
3953 (void) string_from_gstring(yield);
3954 return yield;
3955 }
3956
3957
3958 #ifndef DISABLE_TLS
3959 static gstring *
3960 cat_file_tls(void * tls_ctx, gstring * yield, uschar * eol)
3961 {
3962 int rc;
3963 uschar buffer[1024];
3964
3965 /*XXX could we read direct into a pre-grown string? */
3966
3967 while ((rc = tls_read(tls_ctx, buffer, sizeof(buffer))) > 0)
3968   for (uschar * s = buffer; rc--; s++)
3969     yield = eol && *s == '\n'
3970       ? string_cat(yield, eol) : string_catn(yield, s, 1);
3971
3972 /* We assume that all errors, and any returns of zero bytes,
3973 are actually EOF. */
3974
3975 (void) string_from_gstring(yield);
3976 return yield;
3977 }
3978 #endif
3979
3980
3981 /*************************************************
3982 *          Evaluate numeric expression           *
3983 *************************************************/
3984
3985 /* This is a set of mutually recursive functions that evaluate an arithmetic
3986 expression involving + - * / % & | ^ ~ << >> and parentheses. The only one of
3987 these functions that is called from elsewhere is eval_expr, whose interface is:
3988
3989 Arguments:
3990   sptr        pointer to the pointer to the string - gets updated
3991   decimal     TRUE if numbers are to be assumed decimal
3992   error       pointer to where to put an error message - must be NULL on input
3993   endket      TRUE if ')' must terminate - FALSE for external call
3994
3995 Returns:      on success: the value of the expression, with *error still NULL
3996               on failure: an undefined value, with *error = a message
3997 */
3998
3999 static int_eximarith_t eval_op_or(uschar **, BOOL, uschar **);
4000
4001
4002 static int_eximarith_t
4003 eval_expr(uschar **sptr, BOOL decimal, uschar **error, BOOL endket)
4004 {
4005 uschar *s = *sptr;
4006 int_eximarith_t x = eval_op_or(&s, decimal, error);
4007
4008 if (!*error)
4009   if (endket)
4010     if (*s != ')')
4011       *error = US"expecting closing parenthesis";
4012     else
4013       while (isspace(*(++s)));
4014   else if (*s)
4015     *error = US"expecting operator";
4016 *sptr = s;
4017 return x;
4018 }
4019
4020
4021 static int_eximarith_t
4022 eval_number(uschar **sptr, BOOL decimal, uschar **error)
4023 {
4024 int c;
4025 int_eximarith_t n;
4026 uschar *s = *sptr;
4027
4028 while (isspace(*s)) s++;
4029 if (isdigit((c = *s)))
4030   {
4031   int count;
4032   (void)sscanf(CS s, (decimal? SC_EXIM_DEC "%n" : SC_EXIM_ARITH "%n"), &n, &count);
4033   s += count;
4034   switch (tolower(*s))
4035     {
4036     default: break;
4037     case 'k': n *= 1024; s++; break;
4038     case 'm': n *= 1024*1024; s++; break;
4039     case 'g': n *= 1024*1024*1024; s++; break;
4040     }
4041   while (isspace (*s)) s++;
4042   }
4043 else if (c == '(')
4044   {
4045   s++;
4046   n = eval_expr(&s, decimal, error, 1);
4047   }
4048 else
4049   {
4050   *error = US"expecting number or opening parenthesis";
4051   n = 0;
4052   }
4053 *sptr = s;
4054 return n;
4055 }
4056
4057
4058 static int_eximarith_t
4059 eval_op_unary(uschar **sptr, BOOL decimal, uschar **error)
4060 {
4061 uschar *s = *sptr;
4062 int_eximarith_t x;
4063 while (isspace(*s)) s++;
4064 if (*s == '+' || *s == '-' || *s == '~')
4065   {
4066   int op = *s++;
4067   x = eval_op_unary(&s, decimal, error);
4068   if (op == '-') x = -x;
4069     else if (op == '~') x = ~x;
4070   }
4071 else
4072   x = eval_number(&s, decimal, error);
4073
4074 *sptr = s;
4075 return x;
4076 }
4077
4078
4079 static int_eximarith_t
4080 eval_op_mult(uschar **sptr, BOOL decimal, uschar **error)
4081 {
4082 uschar *s = *sptr;
4083 int_eximarith_t x = eval_op_unary(&s, decimal, error);
4084 if (!*error)
4085   {
4086   while (*s == '*' || *s == '/' || *s == '%')
4087     {
4088     int op = *s++;
4089     int_eximarith_t y = eval_op_unary(&s, decimal, error);
4090     if (*error) break;
4091     /* SIGFPE both on div/mod by zero and on INT_MIN / -1, which would give
4092      * a value of INT_MAX+1. Note that INT_MIN * -1 gives INT_MIN for me, which
4093      * is a bug somewhere in [gcc 4.2.1, FreeBSD, amd64].  In fact, -N*-M where
4094      * -N*M is INT_MIN will yield INT_MIN.
4095      * Since we don't support floating point, this is somewhat simpler.
4096      * Ideally, we'd return an error, but since we overflow for all other
4097      * arithmetic, consistency suggests otherwise, but what's the correct value
4098      * to use?  There is none.
4099      * The C standard guarantees overflow for unsigned arithmetic but signed
4100      * overflow invokes undefined behaviour; in practice, this is overflow
4101      * except for converting INT_MIN to INT_MAX+1.  We also can't guarantee
4102      * that long/longlong larger than int are available, or we could just work
4103      * with larger types.  We should consider whether to guarantee 32bit eval
4104      * and 64-bit working variables, with errors returned.  For now ...
4105      * So, the only SIGFPEs occur with a non-shrinking div/mod, thus -1; we
4106      * can just let the other invalid results occur otherwise, as they have
4107      * until now.  For this one case, we can coerce.
4108      */
4109     if (y == -1 && x == EXIM_ARITH_MIN && op != '*')
4110       {
4111       DEBUG(D_expand)
4112         debug_printf("Integer exception dodging: " PR_EXIM_ARITH "%c-1 coerced to " PR_EXIM_ARITH "\n",
4113             EXIM_ARITH_MIN, op, EXIM_ARITH_MAX);
4114       x = EXIM_ARITH_MAX;
4115       continue;
4116       }
4117     if (op == '*')
4118       x *= y;
4119     else
4120       {
4121       if (y == 0)
4122         {
4123         *error = (op == '/') ? US"divide by zero" : US"modulo by zero";
4124         x = 0;
4125         break;
4126         }
4127       if (op == '/')
4128         x /= y;
4129       else
4130         x %= y;
4131       }
4132     }
4133   }
4134 *sptr = s;
4135 return x;
4136 }
4137
4138
4139 static int_eximarith_t
4140 eval_op_sum(uschar **sptr, BOOL decimal, uschar **error)
4141 {
4142 uschar *s = *sptr;
4143 int_eximarith_t x = eval_op_mult(&s, decimal, error);
4144 if (!*error)
4145   {
4146   while (*s == '+' || *s == '-')
4147     {
4148     int op = *s++;
4149     int_eximarith_t y = eval_op_mult(&s, decimal, error);
4150     if (*error) break;
4151     if (  (x >=   EXIM_ARITH_MAX/2  && x >=   EXIM_ARITH_MAX/2)
4152        || (x <= -(EXIM_ARITH_MAX/2) && y <= -(EXIM_ARITH_MAX/2)))
4153       {                 /* over-conservative check */
4154       *error = op == '+'
4155         ? US"overflow in sum" : US"overflow in difference";
4156       break;
4157       }
4158     if (op == '+') x += y; else x -= y;
4159     }
4160   }
4161 *sptr = s;
4162 return x;
4163 }
4164
4165
4166 static int_eximarith_t
4167 eval_op_shift(uschar **sptr, BOOL decimal, uschar **error)
4168 {
4169 uschar *s = *sptr;
4170 int_eximarith_t x = eval_op_sum(&s, decimal, error);
4171 if (!*error)
4172   {
4173   while ((*s == '<' || *s == '>') && s[1] == s[0])
4174     {
4175     int_eximarith_t y;
4176     int op = *s++;
4177     s++;
4178     y = eval_op_sum(&s, decimal, error);
4179     if (*error) break;
4180     if (op == '<') x <<= y; else x >>= y;
4181     }
4182   }
4183 *sptr = s;
4184 return x;
4185 }
4186
4187
4188 static int_eximarith_t
4189 eval_op_and(uschar **sptr, BOOL decimal, uschar **error)
4190 {
4191 uschar *s = *sptr;
4192 int_eximarith_t x = eval_op_shift(&s, decimal, error);
4193 if (!*error)
4194   {
4195   while (*s == '&')
4196     {
4197     int_eximarith_t y;
4198     s++;
4199     y = eval_op_shift(&s, decimal, error);
4200     if (*error) break;
4201     x &= y;
4202     }
4203   }
4204 *sptr = s;
4205 return x;
4206 }
4207
4208
4209 static int_eximarith_t
4210 eval_op_xor(uschar **sptr, BOOL decimal, uschar **error)
4211 {
4212 uschar *s = *sptr;
4213 int_eximarith_t x = eval_op_and(&s, decimal, error);
4214 if (!*error)
4215   {
4216   while (*s == '^')
4217     {
4218     int_eximarith_t y;
4219     s++;
4220     y = eval_op_and(&s, decimal, error);
4221     if (*error) break;
4222     x ^= y;
4223     }
4224   }
4225 *sptr = s;
4226 return x;
4227 }
4228
4229
4230 static int_eximarith_t
4231 eval_op_or(uschar **sptr, BOOL decimal, uschar **error)
4232 {
4233 uschar *s = *sptr;
4234 int_eximarith_t x = eval_op_xor(&s, decimal, error);
4235 if (!*error)
4236   {
4237   while (*s == '|')
4238     {
4239     int_eximarith_t y;
4240     s++;
4241     y = eval_op_xor(&s, decimal, error);
4242     if (*error) break;
4243     x |= y;
4244     }
4245   }
4246 *sptr = s;
4247 return x;
4248 }
4249
4250
4251
4252 /************************************************/
4253 /* Comparison operation for sort expansion.  We need to avoid
4254 re-expanding the fields being compared, so need a custom routine.
4255
4256 Arguments:
4257  cond_type              Comparison operator code
4258  leftarg, rightarg      Arguments for comparison
4259
4260 Return true iff (leftarg compare rightarg)
4261 */
4262
4263 static BOOL
4264 sortsbefore(int cond_type, BOOL alpha_cond,
4265   const uschar * leftarg, const uschar * rightarg)
4266 {
4267 int_eximarith_t l_num, r_num;
4268
4269 if (!alpha_cond)
4270   {
4271   l_num = expanded_string_integer(leftarg, FALSE);
4272   if (expand_string_message) return FALSE;
4273   r_num = expanded_string_integer(rightarg, FALSE);
4274   if (expand_string_message) return FALSE;
4275
4276   switch (cond_type)
4277     {
4278     case ECOND_NUM_G:   return l_num >  r_num;
4279     case ECOND_NUM_GE:  return l_num >= r_num;
4280     case ECOND_NUM_L:   return l_num <  r_num;
4281     case ECOND_NUM_LE:  return l_num <= r_num;
4282     default: break;
4283     }
4284   }
4285 else
4286   switch (cond_type)
4287     {
4288     case ECOND_STR_LT:  return Ustrcmp (leftarg, rightarg) <  0;
4289     case ECOND_STR_LTI: return strcmpic(leftarg, rightarg) <  0;
4290     case ECOND_STR_LE:  return Ustrcmp (leftarg, rightarg) <= 0;
4291     case ECOND_STR_LEI: return strcmpic(leftarg, rightarg) <= 0;
4292     case ECOND_STR_GT:  return Ustrcmp (leftarg, rightarg) >  0;
4293     case ECOND_STR_GTI: return strcmpic(leftarg, rightarg) >  0;
4294     case ECOND_STR_GE:  return Ustrcmp (leftarg, rightarg) >= 0;
4295     case ECOND_STR_GEI: return strcmpic(leftarg, rightarg) >= 0;
4296     default: break;
4297     }
4298 return FALSE;   /* should not happen */
4299 }
4300
4301
4302 /*************************************************
4303 *                 Expand string                  *
4304 *************************************************/
4305
4306 /* Returns either an unchanged string, or the expanded string in stacking pool
4307 store. Interpreted sequences are:
4308
4309    \...                    normal escaping rules
4310    $name                   substitutes the variable
4311    ${name}                 ditto
4312    ${op:string}            operates on the expanded string value
4313    ${item{arg1}{arg2}...}  expands the args and then does the business
4314                              some literal args are not enclosed in {}
4315
4316 There are now far too many operators and item types to make it worth listing
4317 them here in detail any more.
4318
4319 We use an internal routine recursively to handle embedded substrings. The
4320 external function follows. The yield is NULL if the expansion failed, and there
4321 are two cases: if something collapsed syntactically, or if "fail" was given
4322 as the action on a lookup failure. These can be distinguished by looking at the
4323 variable expand_string_forcedfail, which is TRUE in the latter case.
4324
4325 The skipping flag is set true when expanding a substring that isn't actually
4326 going to be used (after "if" or "lookup") and it prevents lookups from
4327 happening lower down.
4328
4329 Store usage: At start, a store block of the length of the input plus 64
4330 is obtained. This is expanded as necessary by string_cat(), which might have to
4331 get a new block, or might be able to expand the original. At the end of the
4332 function we can release any store above that portion of the yield block that
4333 was actually used. In many cases this will be optimal.
4334
4335 However: if the first item in the expansion is a variable name or header name,
4336 we reset the store before processing it; if the result is in fresh store, we
4337 use that without copying. This is helpful for expanding strings like
4338 $message_headers which can get very long.
4339
4340 There's a problem if a ${dlfunc item has side-effects that cause allocation,
4341 since resetting the store at the end of the expansion will free store that was
4342 allocated by the plugin code as well as the slop after the expanded string. So
4343 we skip any resets if ${dlfunc } has been used. The same applies for ${acl }
4344 and, given the acl condition, ${if }. This is an unfortunate consequence of
4345 string expansion becoming too powerful.
4346
4347 Arguments:
4348   string         the string to be expanded
4349   ket_ends       true if expansion is to stop at }
4350   left           if not NULL, a pointer to the first character after the
4351                  expansion is placed here (typically used with ket_ends)
4352   skipping       TRUE for recursive calls when the value isn't actually going
4353                  to be used (to allow for optimisation)
4354   honour_dollar  TRUE if $ is to be expanded,
4355                  FALSE if it's just another character
4356   resetok_p      if not NULL, pointer to flag - write FALSE if unsafe to reset
4357                  the store.
4358
4359 Returns:         NULL if expansion fails:
4360                    expand_string_forcedfail is set TRUE if failure was forced
4361                    expand_string_message contains a textual error message
4362                  a pointer to the expanded string on success
4363 */
4364
4365 static uschar *
4366 expand_string_internal(const uschar *string, BOOL ket_ends, const uschar **left,
4367   BOOL skipping, BOOL honour_dollar, BOOL *resetok_p)
4368 {
4369 rmark reset_point = store_mark();
4370 gstring * yield = string_get(Ustrlen(string) + 64);
4371 int item_type;
4372 const uschar *s = string;
4373 uschar *save_expand_nstring[EXPAND_MAXN+1];
4374 int save_expand_nlength[EXPAND_MAXN+1];
4375 BOOL resetok = TRUE;
4376
4377 expand_level++;
4378 DEBUG(D_expand)
4379   DEBUG(D_noutf8)
4380     debug_printf_indent("/%s: %s\n",
4381       skipping ? "---scanning" : "considering", string);
4382   else
4383     debug_printf_indent(UTF8_DOWN_RIGHT "%s: %s\n",
4384       skipping
4385       ? UTF8_HORIZ UTF8_HORIZ UTF8_HORIZ "scanning"
4386       : "considering",
4387       string);
4388
4389 f.expand_string_forcedfail = FALSE;
4390 expand_string_message = US"";
4391
4392 if (is_tainted(string))
4393   {
4394   expand_string_message =
4395     string_sprintf("attempt to expand tainted string '%s'", s);
4396   log_write(0, LOG_MAIN|LOG_PANIC, "%s", expand_string_message);
4397   goto EXPAND_FAILED;
4398   }
4399
4400 while (*s != 0)
4401   {
4402   uschar *value;
4403   uschar name[256];
4404
4405   /* \ escapes the next character, which must exist, or else
4406   the expansion fails. There's a special escape, \N, which causes
4407   copying of the subject verbatim up to the next \N. Otherwise,
4408   the escapes are the standard set. */
4409
4410   if (*s == '\\')
4411     {
4412     if (s[1] == 0)
4413       {
4414       expand_string_message = US"\\ at end of string";
4415       goto EXPAND_FAILED;
4416       }
4417
4418     if (s[1] == 'N')
4419       {
4420       const uschar * t = s + 2;
4421       for (s = t; *s != 0; s++) if (*s == '\\' && s[1] == 'N') break;
4422       yield = string_catn(yield, t, s - t);
4423       if (*s != 0) s += 2;
4424       }
4425
4426     else
4427       {
4428       uschar ch[1];
4429       ch[0] = string_interpret_escape(&s);
4430       s++;
4431       yield = string_catn(yield, ch, 1);
4432       }
4433
4434     continue;
4435     }
4436
4437   /*{*/
4438   /* Anything other than $ is just copied verbatim, unless we are
4439   looking for a terminating } character. */
4440
4441   /*{*/
4442   if (ket_ends && *s == '}') break;
4443
4444   if (*s != '$' || !honour_dollar)
4445     {
4446     yield = string_catn(yield, s++, 1);
4447     continue;
4448     }
4449
4450   /* No { after the $ - must be a plain name or a number for string
4451   match variable. There has to be a fudge for variables that are the
4452   names of header fields preceded by "$header_" because header field
4453   names can contain any printing characters except space and colon.
4454   For those that don't like typing this much, "$h_" is a synonym for
4455   "$header_". A non-existent header yields a NULL value; nothing is
4456   inserted. */  /*}*/
4457
4458   if (isalpha((*(++s))))
4459     {
4460     int len;
4461     int newsize = 0;
4462     gstring * g = NULL;
4463     uschar * t;
4464
4465     s = read_name(name, sizeof(name), s, US"_");
4466
4467     /* If this is the first thing to be expanded, release the pre-allocated
4468     buffer. */
4469
4470     if (!yield)
4471       g = store_get(sizeof(gstring), FALSE);
4472     else if (yield->ptr == 0)
4473       {
4474       if (resetok) reset_point = store_reset(reset_point);
4475       yield = NULL;
4476       reset_point = store_mark();
4477       g = store_get(sizeof(gstring), FALSE);    /* alloc _before_ calling find_variable() */
4478       }
4479
4480     /* Header */
4481
4482     if (  ( *(t = name) == 'h'
4483           || (*t == 'r' || *t == 'l' || *t == 'b') && *++t == 'h'
4484           )
4485        && (*++t == '_' || Ustrncmp(t, "eader_", 6) == 0)
4486        )
4487       {
4488       unsigned flags = *name == 'r' ? FH_WANT_RAW
4489                       : *name == 'l' ? FH_WANT_RAW|FH_WANT_LIST
4490                       : 0;
4491       uschar * charset = *name == 'b' ? NULL : headers_charset;
4492
4493       s = read_header_name(name, sizeof(name), s);
4494       value = find_header(name, &newsize, flags, charset);
4495
4496       /* If we didn't find the header, and the header contains a closing brace
4497       character, this may be a user error where the terminating colon
4498       has been omitted. Set a flag to adjust the error message in this case.
4499       But there is no error here - nothing gets inserted. */
4500
4501       if (!value)
4502         {
4503         if (Ustrchr(name, '}')) malformed_header = TRUE;
4504         continue;
4505         }
4506       }
4507
4508     /* Variable */
4509
4510     else if (!(value = find_variable(name, FALSE, skipping, &newsize)))
4511       {
4512       expand_string_message =
4513         string_sprintf("unknown variable name \"%s\"", name);
4514         check_variable_error_message(name);
4515       goto EXPAND_FAILED;
4516       }
4517
4518     /* If the data is known to be in a new buffer, newsize will be set to the
4519     size of that buffer. If this is the first thing in an expansion string,
4520     yield will be NULL; just point it at the new store instead of copying. Many
4521     expansion strings contain just one reference, so this is a useful
4522     optimization, especially for humungous headers.  We need to use a gstring
4523     structure that is not allocated after that new-buffer, else a later store
4524     reset in the middle of the buffer will make it inaccessible. */
4525
4526     len = Ustrlen(value);
4527     if (!yield && newsize != 0)
4528       {
4529       yield = g;
4530       yield->size = newsize;
4531       yield->ptr = len;
4532       yield->s = value;
4533       }
4534     else
4535       yield = string_catn(yield, value, len);
4536
4537     continue;
4538     }
4539
4540   if (isdigit(*s))
4541     {
4542     int n;
4543     s = read_cnumber(&n, s);
4544     if (n >= 0 && n <= expand_nmax)
4545       yield = string_catn(yield, expand_nstring[n], expand_nlength[n]);
4546     continue;
4547     }
4548
4549   /* Otherwise, if there's no '{' after $ it's an error. */             /*}*/
4550
4551   if (*s != '{')                                                        /*}*/
4552     {
4553     expand_string_message = US"$ not followed by letter, digit, or {";  /*}*/
4554     goto EXPAND_FAILED;
4555     }
4556
4557   /* After { there can be various things, but they all start with
4558   an initial word, except for a number for a string match variable. */
4559
4560   if (isdigit((*(++s))))
4561     {
4562     int n;
4563     s = read_cnumber(&n, s);            /*{*/
4564     if (*s++ != '}')
4565       {                                 /*{*/
4566       expand_string_message = US"} expected after number";
4567       goto EXPAND_FAILED;
4568       }
4569     if (n >= 0 && n <= expand_nmax)
4570       yield = string_catn(yield, expand_nstring[n], expand_nlength[n]);
4571     continue;
4572     }
4573
4574   if (!isalpha(*s))
4575     {
4576     expand_string_message = US"letter or digit expected after ${";      /*}*/
4577     goto EXPAND_FAILED;
4578     }
4579
4580   /* Allow "-" in names to cater for substrings with negative
4581   arguments. Since we are checking for known names after { this is
4582   OK. */
4583
4584   s = read_name(name, sizeof(name), s, US"_-");
4585   item_type = chop_match(name, item_table, nelem(item_table));
4586
4587   switch(item_type)
4588     {
4589     /* Call an ACL from an expansion.  We feed data in via $acl_arg1 - $acl_arg9.
4590     If the ACL returns accept or reject we return content set by "message ="
4591     There is currently no limit on recursion; this would have us call
4592     acl_check_internal() directly and get a current level from somewhere.
4593     See also the acl expansion condition ECOND_ACL and the traditional
4594     acl modifier ACLC_ACL.
4595     Assume that the function has side-effects on the store that must be preserved.
4596     */
4597
4598     case EITEM_ACL:
4599       /* ${acl {name} {arg1}{arg2}...} */
4600       {
4601       uschar *sub[10];  /* name + arg1-arg9 (which must match number of acl_arg[]) */
4602       uschar *user_msg;
4603       int rc;
4604
4605       switch(read_subs(sub, nelem(sub), 1, &s, skipping, TRUE, US"acl",
4606                       &resetok))
4607         {
4608         case 1: goto EXPAND_FAILED_CURLY;
4609         case 2:
4610         case 3: goto EXPAND_FAILED;
4611         }
4612       if (skipping) continue;
4613
4614       resetok = FALSE;
4615       switch(rc = eval_acl(sub, nelem(sub), &user_msg))
4616         {
4617         case OK:
4618         case FAIL:
4619           DEBUG(D_expand)
4620             debug_printf_indent("acl expansion yield: %s\n", user_msg);
4621           if (user_msg)
4622             yield = string_cat(yield, user_msg);
4623           continue;
4624
4625         case DEFER:
4626           f.expand_string_forcedfail = TRUE;
4627           /*FALLTHROUGH*/
4628         default:
4629           expand_string_message = string_sprintf("%s from acl \"%s\"",
4630             rc_names[rc], sub[0]);
4631           goto EXPAND_FAILED;
4632         }
4633       }
4634
4635     case EITEM_AUTHRESULTS:
4636       /* ${authresults {mysystemname}} */
4637       {
4638       uschar *sub_arg[1];
4639
4640       switch(read_subs(sub_arg, nelem(sub_arg), 1, &s, skipping, TRUE, name,
4641                       &resetok))
4642         {
4643         case 1: goto EXPAND_FAILED_CURLY;
4644         case 2:
4645         case 3: goto EXPAND_FAILED;
4646         }
4647
4648       yield = string_append(yield, 3,
4649                         US"Authentication-Results: ", sub_arg[0], US"; none");
4650       yield->ptr -= 6;
4651
4652       yield = authres_local(yield, sub_arg[0]);
4653       yield = authres_iprev(yield);
4654       yield = authres_smtpauth(yield);
4655 #ifdef SUPPORT_SPF
4656       yield = authres_spf(yield);
4657 #endif
4658 #ifndef DISABLE_DKIM
4659       yield = authres_dkim(yield);
4660 #endif
4661 #ifdef SUPPORT_DMARC
4662       yield = authres_dmarc(yield);
4663 #endif
4664 #ifdef EXPERIMENTAL_ARC
4665       yield = authres_arc(yield);
4666 #endif
4667       continue;
4668       }
4669
4670     /* Handle conditionals - preserve the values of the numerical expansion
4671     variables in case they get changed by a regular expression match in the
4672     condition. If not, they retain their external settings. At the end
4673     of this "if" section, they get restored to their previous values. */
4674
4675     case EITEM_IF:
4676       {
4677       BOOL cond = FALSE;
4678       const uschar *next_s;
4679       int save_expand_nmax =
4680         save_expand_strings(save_expand_nstring, save_expand_nlength);
4681
4682       while (isspace(*s)) s++;
4683       if (!(next_s = eval_condition(s, &resetok, skipping ? NULL : &cond)))
4684         goto EXPAND_FAILED;  /* message already set */
4685
4686       DEBUG(D_expand)
4687         DEBUG(D_noutf8)
4688           {
4689           debug_printf_indent("|--condition: %.*s\n", (int)(next_s - s), s);
4690           debug_printf_indent("|-----result: %s\n", cond ? "true" : "false");
4691           }
4692         else
4693           {
4694           debug_printf_indent(UTF8_VERT_RIGHT UTF8_HORIZ UTF8_HORIZ
4695             "condition: %.*s\n",
4696             (int)(next_s - s), s);
4697           debug_printf_indent(UTF8_VERT_RIGHT UTF8_HORIZ UTF8_HORIZ
4698             UTF8_HORIZ UTF8_HORIZ UTF8_HORIZ
4699             "result: %s\n",
4700             cond ? "true" : "false");
4701           }
4702
4703       s = next_s;
4704
4705       /* The handling of "yes" and "no" result strings is now in a separate
4706       function that is also used by ${lookup} and ${extract} and ${run}. */
4707
4708       switch(process_yesno(
4709                skipping,                     /* were previously skipping */
4710                cond,                         /* success/failure indicator */
4711                lookup_value,                 /* value to reset for string2 */
4712                &s,                           /* input pointer */
4713                &yield,                       /* output pointer */
4714                US"if",                       /* condition type */
4715                &resetok))
4716         {
4717         case 1: goto EXPAND_FAILED;          /* when all is well, the */
4718         case 2: goto EXPAND_FAILED_CURLY;    /* returned value is 0 */
4719         }
4720
4721       /* Restore external setting of expansion variables for continuation
4722       at this level. */
4723
4724       restore_expand_strings(save_expand_nmax, save_expand_nstring,
4725         save_expand_nlength);
4726       continue;
4727       }
4728
4729 #ifdef SUPPORT_I18N
4730     case EITEM_IMAPFOLDER:
4731       {                         /* ${imapfolder {name}{sep]{specials}} */
4732       uschar *sub_arg[3];
4733       uschar *encoded;
4734
4735       switch(read_subs(sub_arg, nelem(sub_arg), 1, &s, skipping, TRUE, name,
4736                       &resetok))
4737         {
4738         case 1: goto EXPAND_FAILED_CURLY;
4739         case 2:
4740         case 3: goto EXPAND_FAILED;
4741         }
4742
4743       if (!sub_arg[1])                  /* One argument */
4744         {
4745         sub_arg[1] = US"/";             /* default separator */
4746         sub_arg[2] = NULL;
4747         }
4748       else if (Ustrlen(sub_arg[1]) != 1)
4749         {
4750         expand_string_message =
4751           string_sprintf(
4752                 "IMAP folder separator must be one character, found \"%s\"",
4753                 sub_arg[1]);
4754         goto EXPAND_FAILED;
4755         }
4756
4757       if (!skipping)
4758         {
4759         if (!(encoded = imap_utf7_encode(sub_arg[0], headers_charset,
4760                             sub_arg[1][0], sub_arg[2], &expand_string_message)))
4761           goto EXPAND_FAILED;
4762         yield = string_cat(yield, encoded);
4763         }
4764       continue;
4765       }
4766 #endif
4767
4768     /* Handle database lookups unless locked out. If "skipping" is TRUE, we are
4769     expanding an internal string that isn't actually going to be used. All we
4770     need to do is check the syntax, so don't do a lookup at all. Preserve the
4771     values of the numerical expansion variables in case they get changed by a
4772     partial lookup. If not, they retain their external settings. At the end
4773     of this "lookup" section, they get restored to their previous values. */
4774
4775     case EITEM_LOOKUP:
4776       {
4777       int stype, partial, affixlen, starflags;
4778       int expand_setup = 0;
4779       int nameptr = 0;
4780       uschar *key, *filename;
4781       const uschar *affix;
4782       uschar *save_lookup_value = lookup_value;
4783       int save_expand_nmax =
4784         save_expand_strings(save_expand_nstring, save_expand_nlength);
4785
4786       if ((expand_forbid & RDO_LOOKUP) != 0)
4787         {
4788         expand_string_message = US"lookup expansions are not permitted";
4789         goto EXPAND_FAILED;
4790         }
4791
4792       /* Get the key we are to look up for single-key+file style lookups.
4793       Otherwise set the key NULL pro-tem. */
4794
4795       while (isspace(*s)) s++;
4796       if (*s == '{')                                    /*}*/
4797         {
4798         key = expand_string_internal(s+1, TRUE, &s, skipping, TRUE, &resetok);
4799         if (!key) goto EXPAND_FAILED;                   /*{{*/
4800         if (*s++ != '}')
4801           {
4802           expand_string_message = US"missing '}' after lookup key";
4803           goto EXPAND_FAILED_CURLY;
4804           }
4805         while (isspace(*s)) s++;
4806         }
4807       else key = NULL;
4808
4809       /* Find out the type of database */
4810
4811       if (!isalpha(*s))
4812         {
4813         expand_string_message = US"missing lookup type";
4814         goto EXPAND_FAILED;
4815         }
4816
4817       /* The type is a string that may contain special characters of various
4818       kinds. Allow everything except space or { to appear; the actual content
4819       is checked by search_findtype_partial. */         /*}*/
4820
4821       while (*s != 0 && *s != '{' && !isspace(*s))      /*}*/
4822         {
4823         if (nameptr < sizeof(name) - 1) name[nameptr++] = *s;
4824         s++;
4825         }
4826       name[nameptr] = 0;
4827       while (isspace(*s)) s++;
4828
4829       /* Now check for the individual search type and any partial or default
4830       options. Only those types that are actually in the binary are valid. */
4831
4832       stype = search_findtype_partial(name, &partial, &affix, &affixlen,
4833         &starflags);
4834       if (stype < 0)
4835         {
4836         expand_string_message = search_error_message;
4837         goto EXPAND_FAILED;
4838         }
4839
4840       /* Check that a key was provided for those lookup types that need it,
4841       and was not supplied for those that use the query style. */
4842
4843       if (!mac_islookup(stype, lookup_querystyle|lookup_absfilequery))
4844         {
4845         if (!key)
4846           {
4847           expand_string_message = string_sprintf("missing {key} for single-"
4848             "key \"%s\" lookup", name);
4849           goto EXPAND_FAILED;
4850           }
4851         }
4852       else
4853         {
4854         if (key)
4855           {
4856           expand_string_message = string_sprintf("a single key was given for "
4857             "lookup type \"%s\", which is not a single-key lookup type", name);
4858           goto EXPAND_FAILED;
4859           }
4860         }
4861
4862       /* Get the next string in brackets and expand it. It is the file name for
4863       single-key+file lookups, and the whole query otherwise. In the case of
4864       queries that also require a file name (e.g. sqlite), the file name comes
4865       first. */
4866
4867       if (*s != '{')
4868         {
4869         expand_string_message = US"missing '{' for lookup file-or-query arg";
4870         goto EXPAND_FAILED_CURLY;
4871         }
4872       if (!(filename = expand_string_internal(s+1, TRUE, &s, skipping, TRUE, &resetok)))
4873         goto EXPAND_FAILED;
4874       if (*s++ != '}')
4875         {
4876         expand_string_message = US"missing '}' closing lookup file-or-query arg";
4877         goto EXPAND_FAILED_CURLY;
4878         }
4879       while (isspace(*s)) s++;
4880
4881       /* If this isn't a single-key+file lookup, re-arrange the variables
4882       to be appropriate for the search_ functions. For query-style lookups,
4883       there is just a "key", and no file name. For the special query-style +
4884       file types, the query (i.e. "key") starts with a file name. */
4885
4886       if (!key)
4887         {
4888         while (isspace(*filename)) filename++;
4889         key = filename;
4890
4891         if (mac_islookup(stype, lookup_querystyle))
4892           filename = NULL;
4893         else
4894           {
4895           if (*filename != '/')
4896             {
4897             expand_string_message = string_sprintf(
4898               "absolute file name expected for \"%s\" lookup", name);
4899             goto EXPAND_FAILED;
4900             }
4901           while (*key != 0 && !isspace(*key)) key++;
4902           if (*key != 0) *key++ = 0;
4903           }
4904         }
4905
4906       /* If skipping, don't do the next bit - just lookup_value == NULL, as if
4907       the entry was not found. Note that there is no search_close() function.
4908       Files are left open in case of re-use. At suitable places in higher logic,
4909       search_tidyup() is called to tidy all open files. This can save opening
4910       the same file several times. However, files may also get closed when
4911       others are opened, if too many are open at once. The rule is that a
4912       handle should not be used after a second search_open().
4913
4914       Request that a partial search sets up $1 and maybe $2 by passing
4915       expand_setup containing zero. If its value changes, reset expand_nmax,
4916       since new variables will have been set. Note that at the end of this
4917       "lookup" section, the old numeric variables are restored. */
4918
4919       if (skipping)
4920         lookup_value = NULL;
4921       else
4922         {
4923         void *handle = search_open(filename, stype, 0, NULL, NULL);
4924         if (!handle)
4925           {
4926           expand_string_message = search_error_message;
4927           goto EXPAND_FAILED;
4928           }
4929         lookup_value = search_find(handle, filename, key, partial, affix,
4930           affixlen, starflags, &expand_setup);
4931         if (f.search_find_defer)
4932           {
4933           expand_string_message =
4934             string_sprintf("lookup of \"%s\" gave DEFER: %s",
4935               string_printing2(key, FALSE), search_error_message);
4936           goto EXPAND_FAILED;
4937           }
4938         if (expand_setup > 0) expand_nmax = expand_setup;
4939         }
4940
4941       /* The handling of "yes" and "no" result strings is now in a separate
4942       function that is also used by ${if} and ${extract}. */
4943
4944       switch(process_yesno(
4945                skipping,                     /* were previously skipping */
4946                lookup_value != NULL,         /* success/failure indicator */
4947                save_lookup_value,            /* value to reset for string2 */
4948                &s,                           /* input pointer */
4949                &yield,                       /* output pointer */
4950                US"lookup",                   /* condition type */
4951                &resetok))
4952         {
4953         case 1: goto EXPAND_FAILED;          /* when all is well, the */
4954         case 2: goto EXPAND_FAILED_CURLY;    /* returned value is 0 */
4955         }
4956
4957       /* Restore external setting of expansion variables for carrying on
4958       at this level, and continue. */
4959
4960       restore_expand_strings(save_expand_nmax, save_expand_nstring,
4961         save_expand_nlength);
4962       continue;
4963       }
4964
4965     /* If Perl support is configured, handle calling embedded perl subroutines,
4966     unless locked out at this time. Syntax is ${perl{sub}} or ${perl{sub}{arg}}
4967     or ${perl{sub}{arg1}{arg2}} or up to a maximum of EXIM_PERL_MAX_ARGS
4968     arguments (defined below). */
4969
4970     #define EXIM_PERL_MAX_ARGS 8
4971
4972     case EITEM_PERL:
4973     #ifndef EXIM_PERL
4974     expand_string_message = US"\"${perl\" encountered, but this facility "      /*}*/
4975       "is not included in this binary";
4976     goto EXPAND_FAILED;
4977
4978     #else   /* EXIM_PERL */
4979       {
4980       uschar *sub_arg[EXIM_PERL_MAX_ARGS + 2];
4981       gstring *new_yield;
4982
4983       if ((expand_forbid & RDO_PERL) != 0)
4984         {
4985         expand_string_message = US"Perl calls are not permitted";
4986         goto EXPAND_FAILED;
4987         }
4988
4989       switch(read_subs(sub_arg, EXIM_PERL_MAX_ARGS + 1, 1, &s, skipping, TRUE,
4990            US"perl", &resetok))
4991         {
4992         case 1: goto EXPAND_FAILED_CURLY;
4993         case 2:
4994         case 3: goto EXPAND_FAILED;
4995         }
4996
4997       /* If skipping, we don't actually do anything */
4998
4999       if (skipping) continue;
5000
5001       /* Start the interpreter if necessary */
5002
5003       if (!opt_perl_started)
5004         {
5005         uschar *initerror;
5006         if (!opt_perl_startup)
5007           {
5008           expand_string_message = US"A setting of perl_startup is needed when "
5009             "using the Perl interpreter";
5010           goto EXPAND_FAILED;
5011           }
5012         DEBUG(D_any) debug_printf("Starting Perl interpreter\n");
5013         if ((initerror = init_perl(opt_perl_startup)))
5014           {
5015           expand_string_message =
5016             string_sprintf("error in perl_startup code: %s\n", initerror);
5017           goto EXPAND_FAILED;
5018           }
5019         opt_perl_started = TRUE;
5020         }
5021
5022       /* Call the function */
5023
5024       sub_arg[EXIM_PERL_MAX_ARGS + 1] = NULL;
5025       new_yield = call_perl_cat(yield, &expand_string_message,
5026         sub_arg[0], sub_arg + 1);
5027
5028       /* NULL yield indicates failure; if the message pointer has been set to
5029       NULL, the yield was undef, indicating a forced failure. Otherwise the
5030       message will indicate some kind of Perl error. */
5031
5032       if (!new_yield)
5033         {
5034         if (!expand_string_message)
5035           {
5036           expand_string_message =
5037             string_sprintf("Perl subroutine \"%s\" returned undef to force "
5038               "failure", sub_arg[0]);
5039           f.expand_string_forcedfail = TRUE;
5040           }
5041         goto EXPAND_FAILED;
5042         }
5043
5044       /* Yield succeeded. Ensure forcedfail is unset, just in case it got
5045       set during a callback from Perl. */
5046
5047       f.expand_string_forcedfail = FALSE;
5048       yield = new_yield;
5049       continue;
5050       }
5051     #endif /* EXIM_PERL */
5052
5053     /* Transform email address to "prvs" scheme to use
5054        as BATV-signed return path */
5055
5056     case EITEM_PRVS:
5057       {
5058       uschar *sub_arg[3];
5059       uschar *p,*domain;
5060
5061       switch(read_subs(sub_arg, 3, 2, &s, skipping, TRUE, US"prvs", &resetok))
5062         {
5063         case 1: goto EXPAND_FAILED_CURLY;
5064         case 2:
5065         case 3: goto EXPAND_FAILED;
5066         }
5067
5068       /* If skipping, we don't actually do anything */
5069       if (skipping) continue;
5070
5071       /* sub_arg[0] is the address */
5072       if (  !(domain = Ustrrchr(sub_arg[0],'@'))
5073          || domain == sub_arg[0] || Ustrlen(domain) == 1)
5074         {
5075         expand_string_message = US"prvs first argument must be a qualified email address";
5076         goto EXPAND_FAILED;
5077         }
5078
5079       /* Calculate the hash. The third argument must be a single-digit
5080       key number, or unset. */
5081
5082       if (  sub_arg[2]
5083          && (!isdigit(sub_arg[2][0]) || sub_arg[2][1] != 0))
5084         {
5085         expand_string_message = US"prvs third argument must be a single digit";
5086         goto EXPAND_FAILED;
5087         }
5088
5089       p = prvs_hmac_sha1(sub_arg[0], sub_arg[1], sub_arg[2], prvs_daystamp(7));
5090       if (!p)
5091         {
5092         expand_string_message = US"prvs hmac-sha1 conversion failed";
5093         goto EXPAND_FAILED;
5094         }
5095
5096       /* Now separate the domain from the local part */
5097       *domain++ = '\0';
5098
5099       yield = string_catn(yield, US"prvs=", 5);
5100       yield = string_catn(yield, sub_arg[2] ? sub_arg[2] : US"0", 1);
5101       yield = string_catn(yield, prvs_daystamp(7), 3);
5102       yield = string_catn(yield, p, 6);
5103       yield = string_catn(yield, US"=", 1);
5104       yield = string_cat (yield, sub_arg[0]);
5105       yield = string_catn(yield, US"@", 1);
5106       yield = string_cat (yield, domain);
5107
5108       continue;
5109       }
5110
5111     /* Check a prvs-encoded address for validity */
5112
5113     case EITEM_PRVSCHECK:
5114       {
5115       uschar *sub_arg[3];
5116       gstring * g;
5117       const pcre *re;
5118       uschar *p;
5119
5120       /* TF: Ugliness: We want to expand parameter 1 first, then set
5121          up expansion variables that are used in the expansion of
5122          parameter 2. So we clone the string for the first
5123          expansion, where we only expand parameter 1.
5124
5125          PH: Actually, that isn't necessary. The read_subs() function is
5126          designed to work this way for the ${if and ${lookup expansions. I've
5127          tidied the code.
5128       */
5129
5130       /* Reset expansion variables */
5131       prvscheck_result = NULL;
5132       prvscheck_address = NULL;
5133       prvscheck_keynum = NULL;
5134
5135       switch(read_subs(sub_arg, 1, 1, &s, skipping, FALSE, US"prvs", &resetok))
5136         {
5137         case 1: goto EXPAND_FAILED_CURLY;
5138         case 2:
5139         case 3: goto EXPAND_FAILED;
5140         }
5141
5142       re = regex_must_compile(US"^prvs\\=([0-9])([0-9]{3})([A-F0-9]{6})\\=(.+)\\@(.+)$",
5143                               TRUE,FALSE);
5144
5145       if (regex_match_and_setup(re,sub_arg[0],0,-1))
5146         {
5147         uschar *local_part = string_copyn(expand_nstring[4],expand_nlength[4]);
5148         uschar *key_num = string_copyn(expand_nstring[1],expand_nlength[1]);
5149         uschar *daystamp = string_copyn(expand_nstring[2],expand_nlength[2]);
5150         uschar *hash = string_copyn(expand_nstring[3],expand_nlength[3]);
5151         uschar *domain = string_copyn(expand_nstring[5],expand_nlength[5]);
5152
5153         DEBUG(D_expand) debug_printf_indent("prvscheck localpart: %s\n", local_part);
5154         DEBUG(D_expand) debug_printf_indent("prvscheck key number: %s\n", key_num);
5155         DEBUG(D_expand) debug_printf_indent("prvscheck daystamp: %s\n", daystamp);
5156         DEBUG(D_expand) debug_printf_indent("prvscheck hash: %s\n", hash);
5157         DEBUG(D_expand) debug_printf_indent("prvscheck domain: %s\n", domain);
5158
5159         /* Set up expansion variables */
5160         g = string_cat (NULL, local_part);
5161         g = string_catn(g, US"@", 1);
5162         g = string_cat (g, domain);
5163         prvscheck_address = string_from_gstring(g);
5164         prvscheck_keynum = string_copy(key_num);
5165
5166         /* Now expand the second argument */
5167         switch(read_subs(sub_arg, 1, 1, &s, skipping, FALSE, US"prvs", &resetok))
5168           {
5169           case 1: goto EXPAND_FAILED_CURLY;
5170           case 2:
5171           case 3: goto EXPAND_FAILED;
5172           }
5173
5174         /* Now we have the key and can check the address. */
5175
5176         p = prvs_hmac_sha1(prvscheck_address, sub_arg[0], prvscheck_keynum,
5177           daystamp);
5178
5179         if (!p)
5180           {
5181           expand_string_message = US"hmac-sha1 conversion failed";
5182           goto EXPAND_FAILED;
5183           }
5184
5185         DEBUG(D_expand) debug_printf_indent("prvscheck: received hash is %s\n", hash);
5186         DEBUG(D_expand) debug_printf_indent("prvscheck:      own hash is %s\n", p);
5187
5188         if (Ustrcmp(p,hash) == 0)
5189           {
5190           /* Success, valid BATV address. Now check the expiry date. */
5191           uschar *now = prvs_daystamp(0);
5192           unsigned int inow = 0,iexpire = 1;
5193
5194           (void)sscanf(CS now,"%u",&inow);
5195           (void)sscanf(CS daystamp,"%u",&iexpire);
5196
5197           /* When "iexpire" is < 7, a "flip" has occurred.
5198              Adjust "inow" accordingly. */
5199           if ( (iexpire < 7) && (inow >= 993) ) inow = 0;
5200
5201           if (iexpire >= inow)
5202             {
5203             prvscheck_result = US"1";
5204             DEBUG(D_expand) debug_printf_indent("prvscheck: success, $pvrs_result set to 1\n");
5205             }
5206           else
5207             {
5208             prvscheck_result = NULL;
5209             DEBUG(D_expand) debug_printf_indent("prvscheck: signature expired, $pvrs_result unset\n");
5210             }
5211           }
5212         else
5213           {
5214           prvscheck_result = NULL;
5215           DEBUG(D_expand) debug_printf_indent("prvscheck: hash failure, $pvrs_result unset\n");
5216           }
5217
5218         /* Now expand the final argument. We leave this till now so that
5219         it can include $prvscheck_result. */
5220
5221         switch(read_subs(sub_arg, 1, 0, &s, skipping, TRUE, US"prvs", &resetok))
5222           {
5223           case 1: goto EXPAND_FAILED_CURLY;
5224           case 2:
5225           case 3: goto EXPAND_FAILED;
5226           }
5227
5228         yield = string_cat(yield,
5229           !sub_arg[0] || !*sub_arg[0] ? prvscheck_address : sub_arg[0]);
5230
5231         /* Reset the "internal" variables afterwards, because they are in
5232         dynamic store that will be reclaimed if the expansion succeeded. */
5233
5234         prvscheck_address = NULL;
5235         prvscheck_keynum = NULL;
5236         }
5237       else
5238         /* Does not look like a prvs encoded address, return the empty string.
5239            We need to make sure all subs are expanded first, so as to skip over
5240            the entire item. */
5241
5242         switch(read_subs(sub_arg, 2, 1, &s, skipping, TRUE, US"prvs", &resetok))
5243           {
5244           case 1: goto EXPAND_FAILED_CURLY;
5245           case 2:
5246           case 3: goto EXPAND_FAILED;
5247           }
5248
5249       continue;
5250       }
5251
5252     /* Handle "readfile" to insert an entire file */
5253
5254     case EITEM_READFILE:
5255       {
5256       FILE *f;
5257       uschar *sub_arg[2];
5258
5259       if ((expand_forbid & RDO_READFILE) != 0)
5260         {
5261         expand_string_message = US"file insertions are not permitted";
5262         goto EXPAND_FAILED;
5263         }
5264
5265       switch(read_subs(sub_arg, 2, 1, &s, skipping, TRUE, US"readfile", &resetok))
5266         {
5267         case 1: goto EXPAND_FAILED_CURLY;
5268         case 2:
5269         case 3: goto EXPAND_FAILED;
5270         }
5271
5272       /* If skipping, we don't actually do anything */
5273
5274       if (skipping) continue;
5275
5276       /* Open the file and read it */
5277
5278       if (!(f = Ufopen(sub_arg[0], "rb")))
5279         {
5280         expand_string_message = string_open_failed(errno, "%s", sub_arg[0]);
5281         goto EXPAND_FAILED;
5282         }
5283
5284       yield = cat_file(f, yield, sub_arg[1]);
5285       (void)fclose(f);
5286       continue;
5287       }
5288
5289     /* Handle "readsocket" to insert data from a socket, either
5290     Inet or Unix domain */
5291
5292     case EITEM_READSOCK:
5293       {
5294       client_conn_ctx cctx;
5295       int timeout = 5;
5296       int save_ptr = gstring_length(yield);
5297       FILE * fp = NULL;
5298       uschar * arg;
5299       uschar * sub_arg[4];
5300       uschar * server_name = NULL;
5301       host_item host;
5302       BOOL do_shutdown = TRUE;
5303       BOOL do_tls = FALSE;      /* Only set under ! DISABLE_TLS */
5304       blob reqstr;
5305
5306       if (expand_forbid & RDO_READSOCK)
5307         {
5308         expand_string_message = US"socket insertions are not permitted";
5309         goto EXPAND_FAILED;
5310         }
5311
5312       /* Read up to 4 arguments, but don't do the end of item check afterwards,
5313       because there may be a string for expansion on failure. */
5314
5315       switch(read_subs(sub_arg, 4, 2, &s, skipping, FALSE, US"readsocket", &resetok))
5316         {
5317         case 1: goto EXPAND_FAILED_CURLY;
5318         case 2:                             /* Won't occur: no end check */
5319         case 3: goto EXPAND_FAILED;
5320         }
5321
5322       /* Grab the request string, if any */
5323
5324       reqstr.data = sub_arg[1];
5325       reqstr.len = Ustrlen(sub_arg[1]);
5326
5327       /* Sort out timeout, if given.  The second arg is a list with the first element
5328       being a time value.  Any more are options of form "name=value".  Currently the
5329       only option recognised is "shutdown". */
5330
5331       if (sub_arg[2])
5332         {
5333         const uschar * list = sub_arg[2];
5334         uschar * item;
5335         int sep = 0;
5336
5337         item = string_nextinlist(&list, &sep, NULL, 0);
5338         if ((timeout = readconf_readtime(item, 0, FALSE)) < 0)
5339           {
5340           expand_string_message = string_sprintf("bad time value %s", item);
5341           goto EXPAND_FAILED;
5342           }
5343
5344         while ((item = string_nextinlist(&list, &sep, NULL, 0)))
5345           if (Ustrncmp(item, US"shutdown=", 9) == 0)
5346             { if (Ustrcmp(item + 9, US"no") == 0) do_shutdown = FALSE; }
5347 #ifndef DISABLE_TLS
5348           else if (Ustrncmp(item, US"tls=", 4) == 0)
5349             { if (Ustrcmp(item + 9, US"no") != 0) do_tls = TRUE; }
5350 #endif
5351         }
5352       else
5353         sub_arg[3] = NULL;                     /* No eol if no timeout */
5354
5355       /* If skipping, we don't actually do anything. Otherwise, arrange to
5356       connect to either an IP or a Unix socket. */
5357
5358       if (!skipping)
5359         {
5360         /* Handle an IP (internet) domain */
5361
5362         if (Ustrncmp(sub_arg[0], "inet:", 5) == 0)
5363           {
5364           int port;
5365           uschar * port_name;
5366
5367           server_name = sub_arg[0] + 5;
5368           port_name = Ustrrchr(server_name, ':');
5369
5370           /* Sort out the port */
5371
5372           if (!port_name)
5373             {
5374             expand_string_message =
5375               string_sprintf("missing port for readsocket %s", sub_arg[0]);
5376             goto EXPAND_FAILED;
5377             }
5378           *port_name++ = 0;           /* Terminate server name */
5379
5380           if (isdigit(*port_name))
5381             {
5382             uschar *end;
5383             port = Ustrtol(port_name, &end, 0);
5384             if (end != port_name + Ustrlen(port_name))
5385               {
5386               expand_string_message =
5387                 string_sprintf("invalid port number %s", port_name);
5388               goto EXPAND_FAILED;
5389               }
5390             }
5391           else
5392             {
5393             struct servent *service_info = getservbyname(CS port_name, "tcp");
5394             if (!service_info)
5395               {
5396               expand_string_message = string_sprintf("unknown port \"%s\"",
5397                 port_name);
5398               goto EXPAND_FAILED;
5399               }
5400             port = ntohs(service_info->s_port);
5401             }
5402
5403           /*XXX we trust that the request is idempotent for TFO.  Hmm. */
5404           cctx.sock = ip_connectedsocket(SOCK_STREAM, server_name, port, port,
5405                   timeout, &host, &expand_string_message,
5406                   do_tls ? NULL : &reqstr);
5407           callout_address = NULL;
5408           if (cctx.sock < 0)
5409             goto SOCK_FAIL;
5410           if (!do_tls)
5411             reqstr.len = 0;
5412           }
5413
5414         /* Handle a Unix domain socket */
5415
5416         else
5417           {
5418           struct sockaddr_un sockun;         /* don't call this "sun" ! */
5419           int rc;
5420
5421           if ((cctx.sock = socket(PF_UNIX, SOCK_STREAM, 0)) == -1)
5422             {
5423             expand_string_message = string_sprintf("failed to create socket: %s",
5424               strerror(errno));
5425             goto SOCK_FAIL;
5426             }
5427
5428           sockun.sun_family = AF_UNIX;
5429           sprintf(sockun.sun_path, "%.*s", (int)(sizeof(sockun.sun_path)-1),
5430             sub_arg[0]);
5431           server_name = US sockun.sun_path;
5432
5433           sigalrm_seen = FALSE;
5434           ALARM(timeout);
5435           rc = connect(cctx.sock, (struct sockaddr *)(&sockun), sizeof(sockun));
5436           ALARM_CLR(0);
5437           if (sigalrm_seen)
5438             {
5439             expand_string_message = US "socket connect timed out";
5440             goto SOCK_FAIL;
5441             }
5442           if (rc < 0)
5443             {
5444             expand_string_message = string_sprintf("failed to connect to socket "
5445               "%s: %s", sub_arg[0], strerror(errno));
5446             goto SOCK_FAIL;
5447             }
5448           host.name = server_name;
5449           host.address = US"";
5450           }
5451
5452         DEBUG(D_expand) debug_printf_indent("connected to socket %s\n", sub_arg[0]);
5453
5454 #ifndef DISABLE_TLS
5455         if (do_tls)
5456           {
5457           smtp_connect_args conn_args = {.host = &host };
5458           tls_support tls_dummy = {.sni=NULL};
5459           uschar * errstr;
5460
5461           if (!tls_client_start(&cctx, &conn_args, NULL, &tls_dummy, &errstr))
5462             {
5463             expand_string_message = string_sprintf("TLS connect failed: %s", errstr);
5464             goto SOCK_FAIL;
5465             }
5466           }
5467 #endif
5468
5469         /* Allow sequencing of test actions */
5470         testharness_pause_ms(100);
5471
5472         /* Write the request string, if not empty or already done */
5473
5474         if (reqstr.len)
5475           {
5476           DEBUG(D_expand) debug_printf_indent("writing \"%s\" to socket\n",
5477             reqstr.data);
5478           if ( (
5479 #ifndef DISABLE_TLS
5480               do_tls ? tls_write(cctx.tls_ctx, reqstr.data, reqstr.len, FALSE) :
5481 #endif
5482                         write(cctx.sock, reqstr.data, reqstr.len)) != reqstr.len)
5483             {
5484             expand_string_message = string_sprintf("request write to socket "
5485               "failed: %s", strerror(errno));
5486             goto SOCK_FAIL;
5487             }
5488           }
5489
5490         /* Shut down the sending side of the socket. This helps some servers to
5491         recognise that it is their turn to do some work. Just in case some
5492         system doesn't have this function, make it conditional. */
5493
5494 #ifdef SHUT_WR
5495         if (!do_tls && do_shutdown) shutdown(cctx.sock, SHUT_WR);
5496 #endif
5497
5498         testharness_pause_ms(100);
5499
5500         /* Now we need to read from the socket, under a timeout. The function
5501         that reads a file can be used. */
5502
5503         if (!do_tls)
5504           fp = fdopen(cctx.sock, "rb");
5505         sigalrm_seen = FALSE;
5506         ALARM(timeout);
5507         yield =
5508 #ifndef DISABLE_TLS
5509           do_tls ? cat_file_tls(cctx.tls_ctx, yield, sub_arg[3]) :
5510 #endif
5511                     cat_file(fp, yield, sub_arg[3]);
5512         ALARM_CLR(0);
5513
5514 #ifndef DISABLE_TLS
5515         if (do_tls)
5516           {
5517           tls_close(cctx.tls_ctx, TRUE);
5518           close(cctx.sock);
5519           }
5520         else
5521 #endif
5522           (void)fclose(fp);
5523
5524         /* After a timeout, we restore the pointer in the result, that is,
5525         make sure we add nothing from the socket. */
5526
5527         if (sigalrm_seen)
5528           {
5529           if (yield) yield->ptr = save_ptr;
5530           expand_string_message = US "socket read timed out";
5531           goto SOCK_FAIL;
5532           }
5533         }
5534
5535       /* The whole thing has worked (or we were skipping). If there is a
5536       failure string following, we need to skip it. */
5537
5538       if (*s == '{')
5539         {
5540         if (!expand_string_internal(s+1, TRUE, &s, TRUE, TRUE, &resetok))
5541           goto EXPAND_FAILED;
5542         if (*s++ != '}')
5543           {
5544           expand_string_message = US"missing '}' closing failstring for readsocket";
5545           goto EXPAND_FAILED_CURLY;
5546           }
5547         while (isspace(*s)) s++;
5548         }
5549
5550     READSOCK_DONE:
5551       if (*s++ != '}')
5552         {
5553         expand_string_message = US"missing '}' closing readsocket";
5554         goto EXPAND_FAILED_CURLY;
5555         }
5556       continue;
5557
5558       /* Come here on failure to create socket, connect socket, write to the
5559       socket, or timeout on reading. If another substring follows, expand and
5560       use it. Otherwise, those conditions give expand errors. */
5561
5562     SOCK_FAIL:
5563       if (*s != '{') goto EXPAND_FAILED;
5564       DEBUG(D_any) debug_printf("%s\n", expand_string_message);
5565       if (!(arg = expand_string_internal(s+1, TRUE, &s, FALSE, TRUE, &resetok)))
5566         goto EXPAND_FAILED;
5567       yield = string_cat(yield, arg);
5568       if (*s++ != '}')
5569         {
5570         expand_string_message = US"missing '}' closing failstring for readsocket";
5571         goto EXPAND_FAILED_CURLY;
5572         }
5573       while (isspace(*s)) s++;
5574       goto READSOCK_DONE;
5575       }
5576
5577     /* Handle "run" to execute a program. */
5578
5579     case EITEM_RUN:
5580       {
5581       FILE *f;
5582       uschar *arg;
5583       const uschar **argv;
5584       pid_t pid;
5585       int fd_in, fd_out;
5586
5587       if ((expand_forbid & RDO_RUN) != 0)
5588         {
5589         expand_string_message = US"running a command is not permitted";
5590         goto EXPAND_FAILED;
5591         }
5592
5593       while (isspace(*s)) s++;
5594       if (*s != '{')
5595         {
5596         expand_string_message = US"missing '{' for command arg of run";
5597         goto EXPAND_FAILED_CURLY;
5598         }
5599       if (!(arg = expand_string_internal(s+1, TRUE, &s, skipping, TRUE, &resetok)))
5600         goto EXPAND_FAILED;
5601       while (isspace(*s)) s++;
5602       if (*s++ != '}')
5603         {
5604         expand_string_message = US"missing '}' closing command arg of run";
5605         goto EXPAND_FAILED_CURLY;
5606         }
5607
5608       if (skipping)   /* Just pretend it worked when we're skipping */
5609         {
5610         runrc = 0;
5611         lookup_value = NULL;
5612         }
5613       else
5614         {
5615         if (!transport_set_up_command(&argv,    /* anchor for arg list */
5616             arg,                                /* raw command */
5617             FALSE,                              /* don't expand the arguments */
5618             0,                                  /* not relevant when... */
5619             NULL,                               /* no transporting address */
5620             US"${run} expansion",               /* for error messages */
5621             &expand_string_message))            /* where to put error message */
5622           goto EXPAND_FAILED;
5623
5624         /* Create the child process, making it a group leader. */
5625
5626         if ((pid = child_open(USS argv, NULL, 0077, &fd_in, &fd_out, TRUE)) < 0)
5627           {
5628           expand_string_message =
5629             string_sprintf("couldn't create child process: %s", strerror(errno));
5630           goto EXPAND_FAILED;
5631           }
5632
5633         /* Nothing is written to the standard input. */
5634
5635         (void)close(fd_in);
5636
5637         /* Read the pipe to get the command's output into $value (which is kept
5638         in lookup_value). Read during execution, so that if the output exceeds
5639         the OS pipe buffer limit, we don't block forever. Remember to not release
5640         memory just allocated for $value. */
5641
5642         resetok = FALSE;
5643         f = fdopen(fd_out, "rb");
5644         sigalrm_seen = FALSE;
5645         ALARM(60);
5646         lookup_value = string_from_gstring(cat_file(f, NULL, NULL));
5647         ALARM_CLR(0);
5648         (void)fclose(f);
5649
5650         /* Wait for the process to finish, applying the timeout, and inspect its
5651         return code for serious disasters. Simple non-zero returns are passed on.
5652         */
5653
5654         if (sigalrm_seen || (runrc = child_close(pid, 30)) < 0)
5655           {
5656           if (sigalrm_seen || runrc == -256)
5657             {
5658             expand_string_message = US"command timed out";
5659             killpg(pid, SIGKILL);       /* Kill the whole process group */
5660             }
5661
5662           else if (runrc == -257)
5663             expand_string_message = string_sprintf("wait() failed: %s",
5664               strerror(errno));
5665
5666           else
5667             expand_string_message = string_sprintf("command killed by signal %d",
5668               -runrc);
5669
5670           goto EXPAND_FAILED;
5671           }
5672         }
5673
5674       /* Process the yes/no strings; $value may be useful in both cases */
5675
5676       switch(process_yesno(
5677                skipping,                     /* were previously skipping */
5678                runrc == 0,                   /* success/failure indicator */
5679                lookup_value,                 /* value to reset for string2 */
5680                &s,                           /* input pointer */
5681                &yield,                       /* output pointer */
5682                US"run",                      /* condition type */
5683                &resetok))
5684         {
5685         case 1: goto EXPAND_FAILED;          /* when all is well, the */
5686         case 2: goto EXPAND_FAILED_CURLY;    /* returned value is 0 */
5687         }
5688
5689       continue;
5690       }
5691
5692     /* Handle character translation for "tr" */
5693
5694     case EITEM_TR:
5695       {
5696       int oldptr = gstring_length(yield);
5697       int o2m;
5698       uschar *sub[3];
5699
5700       switch(read_subs(sub, 3, 3, &s, skipping, TRUE, US"tr", &resetok))
5701         {
5702         case 1: goto EXPAND_FAILED_CURLY;
5703         case 2:
5704         case 3: goto EXPAND_FAILED;
5705         }
5706
5707       yield = string_cat(yield, sub[0]);
5708       o2m = Ustrlen(sub[2]) - 1;
5709
5710       if (o2m >= 0) for (; oldptr < yield->ptr; oldptr++)
5711         {
5712         uschar *m = Ustrrchr(sub[1], yield->s[oldptr]);
5713         if (m)
5714           {
5715           int o = m - sub[1];
5716           yield->s[oldptr] = sub[2][(o < o2m)? o : o2m];
5717           }
5718         }
5719
5720       continue;
5721       }
5722
5723     /* Handle "hash", "length", "nhash", and "substr" when they are given with
5724     expanded arguments. */
5725
5726     case EITEM_HASH:
5727     case EITEM_LENGTH:
5728     case EITEM_NHASH:
5729     case EITEM_SUBSTR:
5730       {
5731       int len;
5732       uschar *ret;
5733       int val[2] = { 0, -1 };
5734       uschar *sub[3];
5735
5736       /* "length" takes only 2 arguments whereas the others take 2 or 3.
5737       Ensure that sub[2] is set in the ${length } case. */
5738
5739       sub[2] = NULL;
5740       switch(read_subs(sub, (item_type == EITEM_LENGTH)? 2:3, 2, &s, skipping,
5741              TRUE, name, &resetok))
5742         {
5743         case 1: goto EXPAND_FAILED_CURLY;
5744         case 2:
5745         case 3: goto EXPAND_FAILED;
5746         }
5747
5748       /* Juggle the arguments if there are only two of them: always move the
5749       string to the last position and make ${length{n}{str}} equivalent to
5750       ${substr{0}{n}{str}}. See the defaults for val[] above. */
5751
5752       if (!sub[2])
5753         {
5754         sub[2] = sub[1];
5755         sub[1] = NULL;
5756         if (item_type == EITEM_LENGTH)
5757           {
5758           sub[1] = sub[0];
5759           sub[0] = NULL;
5760           }
5761         }
5762
5763       for (int i = 0; i < 2; i++) if (sub[i])
5764         {
5765         val[i] = (int)Ustrtol(sub[i], &ret, 10);
5766         if (*ret != 0 || (i != 0 && val[i] < 0))
5767           {
5768           expand_string_message = string_sprintf("\"%s\" is not a%s number "
5769             "(in \"%s\" expansion)", sub[i], (i != 0)? " positive" : "", name);
5770           goto EXPAND_FAILED;
5771           }
5772         }
5773
5774       ret =
5775         item_type == EITEM_HASH
5776         ?  compute_hash(sub[2], val[0], val[1], &len)
5777         : item_type == EITEM_NHASH
5778         ? compute_nhash(sub[2], val[0], val[1], &len)
5779         : extract_substr(sub[2], val[0], val[1], &len);
5780       if (!ret)
5781         goto EXPAND_FAILED;
5782       yield = string_catn(yield, ret, len);
5783       continue;
5784       }
5785
5786     /* Handle HMAC computation: ${hmac{<algorithm>}{<secret>}{<text>}}
5787     This code originally contributed by Steve Haslam. It currently supports
5788     the use of MD5 and SHA-1 hashes.
5789
5790     We need some workspace that is large enough to handle all the supported
5791     hash types. Use macros to set the sizes rather than be too elaborate. */
5792
5793     #define MAX_HASHLEN      20
5794     #define MAX_HASHBLOCKLEN 64
5795
5796     case EITEM_HMAC:
5797       {
5798       uschar *sub[3];
5799       md5 md5_base;
5800       hctx sha1_ctx;
5801       void *use_base;
5802       int type;
5803       int hashlen;      /* Number of octets for the hash algorithm's output */
5804       int hashblocklen; /* Number of octets the hash algorithm processes */
5805       uschar *keyptr, *p;
5806       unsigned int keylen;
5807
5808       uschar keyhash[MAX_HASHLEN];
5809       uschar innerhash[MAX_HASHLEN];
5810       uschar finalhash[MAX_HASHLEN];
5811       uschar finalhash_hex[2*MAX_HASHLEN];
5812       uschar innerkey[MAX_HASHBLOCKLEN];
5813       uschar outerkey[MAX_HASHBLOCKLEN];
5814
5815       switch (read_subs(sub, 3, 3, &s, skipping, TRUE, name, &resetok))
5816         {
5817         case 1: goto EXPAND_FAILED_CURLY;
5818         case 2:
5819         case 3: goto EXPAND_FAILED;
5820         }
5821
5822       if (!skipping)
5823         {
5824         if (Ustrcmp(sub[0], "md5") == 0)
5825           {
5826           type = HMAC_MD5;
5827           use_base = &md5_base;
5828           hashlen = 16;
5829           hashblocklen = 64;
5830           }
5831         else if (Ustrcmp(sub[0], "sha1") == 0)
5832           {
5833           type = HMAC_SHA1;
5834           use_base = &sha1_ctx;
5835           hashlen = 20;
5836           hashblocklen = 64;
5837           }
5838         else
5839           {
5840           expand_string_message =
5841             string_sprintf("hmac algorithm \"%s\" is not recognised", sub[0]);
5842           goto EXPAND_FAILED;
5843           }
5844
5845         keyptr = sub[1];
5846         keylen = Ustrlen(keyptr);
5847
5848         /* If the key is longer than the hash block length, then hash the key
5849         first */
5850
5851         if (keylen > hashblocklen)
5852           {
5853           chash_start(type, use_base);
5854           chash_end(type, use_base, keyptr, keylen, keyhash);
5855           keyptr = keyhash;
5856           keylen = hashlen;
5857           }
5858
5859         /* Now make the inner and outer key values */
5860
5861         memset(innerkey, 0x36, hashblocklen);
5862         memset(outerkey, 0x5c, hashblocklen);
5863
5864         for (int i = 0; i < keylen; i++)
5865           {
5866           innerkey[i] ^= keyptr[i];
5867           outerkey[i] ^= keyptr[i];
5868           }
5869
5870         /* Now do the hashes */
5871
5872         chash_start(type, use_base);
5873         chash_mid(type, use_base, innerkey);
5874         chash_end(type, use_base, sub[2], Ustrlen(sub[2]), innerhash);
5875
5876         chash_start(type, use_base);
5877         chash_mid(type, use_base, outerkey);
5878         chash_end(type, use_base, innerhash, hashlen, finalhash);
5879
5880         /* Encode the final hash as a hex string */
5881
5882         p = finalhash_hex;
5883         for (int i = 0; i < hashlen; i++)
5884           {
5885           *p++ = hex_digits[(finalhash[i] & 0xf0) >> 4];
5886           *p++ = hex_digits[finalhash[i] & 0x0f];
5887           }
5888
5889         DEBUG(D_any) debug_printf("HMAC[%s](%.*s,%s)=%.*s\n",
5890           sub[0], (int)keylen, keyptr, sub[2], hashlen*2, finalhash_hex);
5891
5892         yield = string_catn(yield, finalhash_hex, hashlen*2);
5893         }
5894       continue;
5895       }
5896
5897     /* Handle global substitution for "sg" - like Perl's s/xxx/yyy/g operator.
5898     We have to save the numerical variables and restore them afterwards. */
5899
5900     case EITEM_SG:
5901       {
5902       const pcre *re;
5903       int moffset, moffsetextra, slen;
5904       int roffset;
5905       int emptyopt;
5906       const uschar *rerror;
5907       uschar *subject;
5908       uschar *sub[3];
5909       int save_expand_nmax =
5910         save_expand_strings(save_expand_nstring, save_expand_nlength);
5911
5912       switch(read_subs(sub, 3, 3, &s, skipping, TRUE, US"sg", &resetok))
5913         {
5914         case 1: goto EXPAND_FAILED_CURLY;
5915         case 2:
5916         case 3: goto EXPAND_FAILED;
5917         }
5918
5919       /* Compile the regular expression */
5920
5921       if (!(re = pcre_compile(CS sub[1], PCRE_COPT, CCSS &rerror,
5922                               &roffset, NULL)))
5923         {
5924         expand_string_message = string_sprintf("regular expression error in "
5925           "\"%s\": %s at offset %d", sub[1], rerror, roffset);
5926         goto EXPAND_FAILED;
5927         }
5928
5929       /* Now run a loop to do the substitutions as often as necessary. It ends
5930       when there are no more matches. Take care over matches of the null string;
5931       do the same thing as Perl does. */
5932
5933       subject = sub[0];
5934       slen = Ustrlen(sub[0]);
5935       moffset = moffsetextra = 0;
5936       emptyopt = 0;
5937
5938       for (;;)
5939         {
5940         int ovector[3*(EXPAND_MAXN+1)];
5941         int n = pcre_exec(re, NULL, CS subject, slen, moffset + moffsetextra,
5942           PCRE_EOPT | emptyopt, ovector, nelem(ovector));
5943         uschar *insert;
5944
5945         /* No match - if we previously set PCRE_NOTEMPTY after a null match, this
5946         is not necessarily the end. We want to repeat the match from one
5947         character further along, but leaving the basic offset the same (for
5948         copying below). We can't be at the end of the string - that was checked
5949         before setting PCRE_NOTEMPTY. If PCRE_NOTEMPTY is not set, we are
5950         finished; copy the remaining string and end the loop. */
5951
5952         if (n < 0)
5953           {
5954           if (emptyopt != 0)
5955             {
5956             moffsetextra = 1;
5957             emptyopt = 0;
5958             continue;
5959             }
5960           yield = string_catn(yield, subject+moffset, slen-moffset);
5961           break;
5962           }
5963
5964         /* Match - set up for expanding the replacement. */
5965
5966         if (n == 0) n = EXPAND_MAXN + 1;
5967         expand_nmax = 0;
5968         for (int nn = 0; nn < n*2; nn += 2)
5969           {
5970           expand_nstring[expand_nmax] = subject + ovector[nn];
5971           expand_nlength[expand_nmax++] = ovector[nn+1] - ovector[nn];
5972           }
5973         expand_nmax--;
5974
5975         /* Copy the characters before the match, plus the expanded insertion. */
5976
5977         yield = string_catn(yield, subject + moffset, ovector[0] - moffset);
5978         if (!(insert = expand_string(sub[2])))
5979           goto EXPAND_FAILED;
5980         yield = string_cat(yield, insert);
5981
5982         moffset = ovector[1];
5983         moffsetextra = 0;
5984         emptyopt = 0;
5985
5986         /* If we have matched an empty string, first check to see if we are at
5987         the end of the subject. If so, the loop is over. Otherwise, mimic
5988         what Perl's /g options does. This turns out to be rather cunning. First
5989         we set PCRE_NOTEMPTY and PCRE_ANCHORED and try the match a non-empty
5990         string at the same point. If this fails (picked up above) we advance to
5991         the next character. */
5992
5993         if (ovector[0] == ovector[1])
5994           {
5995           if (ovector[0] == slen) break;
5996           emptyopt = PCRE_NOTEMPTY | PCRE_ANCHORED;
5997           }
5998         }
5999
6000       /* All done - restore numerical variables. */
6001
6002       restore_expand_strings(save_expand_nmax, save_expand_nstring,
6003         save_expand_nlength);
6004       continue;
6005       }
6006
6007     /* Handle keyed and numbered substring extraction. If the first argument
6008     consists entirely of digits, then a numerical extraction is assumed. */
6009
6010     case EITEM_EXTRACT:
6011       {
6012       int field_number = 1;
6013       BOOL field_number_set = FALSE;
6014       uschar *save_lookup_value = lookup_value;
6015       uschar *sub[3];
6016       int save_expand_nmax =
6017         save_expand_strings(save_expand_nstring, save_expand_nlength);
6018
6019       /* On reflection the original behaviour of extract-json for a string
6020       result, leaving it quoted, was a mistake.  But it was already published,
6021       hence the addition of jsons.  In a future major version, make json
6022       work like josons, and withdraw jsons. */
6023
6024       enum {extract_basic, extract_json, extract_jsons} fmt = extract_basic;
6025
6026       while (isspace(*s)) s++;
6027
6028       /* Check for a format-variant specifier */
6029
6030       if (*s != '{')                                    /*}*/
6031         if (Ustrncmp(s, "json", 4) == 0)
6032           if (*(s += 4) == 's')
6033             {fmt = extract_jsons; s++;}
6034           else
6035             fmt = extract_json;
6036
6037       /* While skipping we cannot rely on the data for expansions being
6038       available (eg. $item) hence cannot decide on numeric vs. keyed.
6039       Read a maximum of 5 arguments (including the yes/no) */
6040
6041       if (skipping)
6042         {
6043         for (int j = 5; j > 0 && *s == '{'; j--)                /*'}'*/
6044           {
6045           if (!expand_string_internal(s+1, TRUE, &s, skipping, TRUE, &resetok))
6046             goto EXPAND_FAILED;                                 /*'{'*/
6047           if (*s++ != '}')
6048             {
6049             expand_string_message = US"missing '{' for arg of extract";
6050             goto EXPAND_FAILED_CURLY;
6051             }
6052           while (isspace(*s)) s++;
6053           }
6054         if (  Ustrncmp(s, "fail", 4) == 0                       /*'{'*/
6055            && (s[4] == '}' || s[4] == ' ' || s[4] == '\t' || !s[4])
6056            )
6057           {
6058           s += 4;
6059           while (isspace(*s)) s++;
6060           }                                                     /*'{'*/
6061         if (*s != '}')
6062           {
6063           expand_string_message = US"missing '}' closing extract";
6064           goto EXPAND_FAILED_CURLY;
6065           }
6066         }
6067
6068       else for (int i = 0, j = 2; i < j; i++) /* Read the proper number of arguments */
6069         {
6070         while (isspace(*s)) s++;
6071         if (*s == '{')                                          /*'}'*/
6072           {
6073           if (!(sub[i] = expand_string_internal(s+1, TRUE, &s, skipping, TRUE, &resetok)))
6074             goto EXPAND_FAILED;                                 /*'{'*/
6075           if (*s++ != '}')
6076             {
6077             expand_string_message = string_sprintf(
6078               "missing '}' closing arg %d of extract", i+1);
6079             goto EXPAND_FAILED_CURLY;
6080             }
6081
6082           /* After removal of leading and trailing white space, the first
6083           argument must not be empty; if it consists entirely of digits
6084           (optionally preceded by a minus sign), this is a numerical
6085           extraction, and we expect 3 arguments (normal) or 2 (json). */
6086
6087           if (i == 0)
6088             {
6089             int len;
6090             int x = 0;
6091             uschar *p = sub[0];
6092
6093             while (isspace(*p)) p++;
6094             sub[0] = p;
6095
6096             len = Ustrlen(p);
6097             while (len > 0 && isspace(p[len-1])) len--;
6098             p[len] = 0;
6099
6100             if (*p == 0)
6101               {
6102               expand_string_message = US"first argument of \"extract\" must "
6103                 "not be empty";
6104               goto EXPAND_FAILED;
6105               }
6106
6107             if (*p == '-')
6108               {
6109               field_number = -1;
6110               p++;
6111               }
6112             while (*p != 0 && isdigit(*p)) x = x * 10 + *p++ - '0';
6113             if (*p == 0)
6114               {
6115               field_number *= x;
6116               if (fmt == extract_basic) j = 3;               /* Need 3 args */
6117               field_number_set = TRUE;
6118               }
6119             }
6120           }
6121         else
6122           {
6123           expand_string_message = string_sprintf(
6124             "missing '{' for arg %d of extract", i+1);
6125           goto EXPAND_FAILED_CURLY;
6126           }
6127         }
6128
6129       /* Extract either the numbered or the keyed substring into $value. If
6130       skipping, just pretend the extraction failed. */
6131
6132       if (skipping)
6133         lookup_value = NULL;
6134       else switch (fmt)
6135         {
6136         case extract_basic:
6137           lookup_value = field_number_set
6138             ? expand_gettokened(field_number, sub[1], sub[2])
6139             : expand_getkeyed(sub[0], sub[1]);
6140           break;
6141
6142         case extract_json:
6143         case extract_jsons:
6144           {
6145           uschar * s, * item;
6146           const uschar * list;
6147
6148           /* Array: Bracket-enclosed and comma-separated.
6149           Object: Brace-enclosed, comma-sep list of name:value pairs */
6150
6151           if (!(s = dewrap(sub[1], field_number_set ? US"[]" : US"{}")))
6152             {
6153             expand_string_message =
6154               string_sprintf("%s wrapping %s for extract json",
6155                 expand_string_message,
6156                 field_number_set ? "array" : "object");
6157             goto EXPAND_FAILED_CURLY;
6158             }
6159
6160           list = s;
6161           if (field_number_set)
6162             {
6163             if (field_number <= 0)
6164               {
6165               expand_string_message = US"first argument of \"extract\" must "
6166                 "be greater than zero";
6167               goto EXPAND_FAILED;
6168               }
6169             while (field_number > 0 && (item = json_nextinlist(&list)))
6170               field_number--;
6171             if ((lookup_value = s = item))
6172               {
6173               while (*s) s++;
6174               while (--s >= lookup_value && isspace(*s)) *s = '\0';
6175               }
6176             }
6177           else
6178             {
6179             lookup_value = NULL;
6180             while ((item = json_nextinlist(&list)))
6181               {
6182               /* Item is:  string name-sep value.  string is quoted.
6183               Dequote the string and compare with the search key. */
6184
6185               if (!(item = dewrap(item, US"\"\"")))
6186                 {
6187                 expand_string_message =
6188                   string_sprintf("%s wrapping string key for extract json",
6189                     expand_string_message);
6190                 goto EXPAND_FAILED_CURLY;
6191                 }
6192               if (Ustrcmp(item, sub[0]) == 0)   /*XXX should be a UTF8-compare */
6193                 {
6194                 s = item + Ustrlen(item) + 1;
6195                 while (isspace(*s)) s++;
6196                 if (*s != ':')
6197                   {
6198                   expand_string_message =
6199                     US"missing object value-separator for extract json";
6200                   goto EXPAND_FAILED_CURLY;
6201                   }
6202                 s++;
6203                 while (isspace(*s)) s++;
6204                 lookup_value = s;
6205                 break;
6206                 }
6207               }
6208             }
6209           }
6210
6211           if (  fmt == extract_jsons
6212              && lookup_value
6213              && !(lookup_value = dewrap(lookup_value, US"\"\"")))
6214             {
6215             expand_string_message =
6216               string_sprintf("%s wrapping string result for extract jsons",
6217                 expand_string_message);
6218             goto EXPAND_FAILED_CURLY;
6219             }
6220           break;        /* json/s */
6221         }
6222
6223       /* If no string follows, $value gets substituted; otherwise there can
6224       be yes/no strings, as for lookup or if. */
6225
6226       switch(process_yesno(
6227                skipping,                     /* were previously skipping */
6228                lookup_value != NULL,         /* success/failure indicator */
6229                save_lookup_value,            /* value to reset for string2 */
6230                &s,                           /* input pointer */
6231                &yield,                       /* output pointer */
6232                US"extract",                  /* condition type */
6233                &resetok))
6234         {
6235         case 1: goto EXPAND_FAILED;          /* when all is well, the */
6236         case 2: goto EXPAND_FAILED_CURLY;    /* returned value is 0 */
6237         }
6238
6239       /* All done - restore numerical variables. */
6240
6241       restore_expand_strings(save_expand_nmax, save_expand_nstring,
6242         save_expand_nlength);
6243
6244       continue;
6245       }
6246
6247     /* return the Nth item from a list */
6248
6249     case EITEM_LISTEXTRACT:
6250       {
6251       int field_number = 1;
6252       uschar *save_lookup_value = lookup_value;
6253       uschar *sub[2];
6254       int save_expand_nmax =
6255         save_expand_strings(save_expand_nstring, save_expand_nlength);
6256
6257       /* Read the field & list arguments */
6258
6259       for (int i = 0; i < 2; i++)
6260         {
6261         while (isspace(*s)) s++;
6262         if (*s != '{')                                  /*'}'*/
6263           {
6264           expand_string_message = string_sprintf(
6265             "missing '{' for arg %d of listextract", i+1);
6266           goto EXPAND_FAILED_CURLY;
6267           }
6268
6269         sub[i] = expand_string_internal(s+1, TRUE, &s, skipping, TRUE, &resetok);
6270         if (!sub[i])     goto EXPAND_FAILED;            /*{*/
6271         if (*s++ != '}')
6272           {
6273           expand_string_message = string_sprintf(
6274             "missing '}' closing arg %d of listextract", i+1);
6275           goto EXPAND_FAILED_CURLY;
6276           }
6277
6278         /* After removal of leading and trailing white space, the first
6279         argument must be numeric and nonempty. */
6280
6281         if (i == 0)
6282           {
6283           int len;
6284           int x = 0;
6285           uschar *p = sub[0];
6286
6287           while (isspace(*p)) p++;
6288           sub[0] = p;
6289
6290           len = Ustrlen(p);
6291           while (len > 0 && isspace(p[len-1])) len--;
6292           p[len] = 0;
6293
6294           if (!*p && !skipping)
6295             {
6296             expand_string_message = US"first argument of \"listextract\" must "
6297               "not be empty";
6298             goto EXPAND_FAILED;
6299             }
6300
6301           if (*p == '-')
6302             {
6303             field_number = -1;
6304             p++;
6305             }
6306           while (*p && isdigit(*p)) x = x * 10 + *p++ - '0';
6307           if (*p)
6308             {
6309             expand_string_message = US"first argument of \"listextract\" must "
6310               "be numeric";
6311             goto EXPAND_FAILED;
6312             }
6313           field_number *= x;
6314           }
6315         }
6316
6317       /* Extract the numbered element into $value. If
6318       skipping, just pretend the extraction failed. */
6319
6320       lookup_value = skipping ? NULL : expand_getlistele(field_number, sub[1]);
6321
6322       /* If no string follows, $value gets substituted; otherwise there can
6323       be yes/no strings, as for lookup or if. */
6324
6325       switch(process_yesno(
6326                skipping,                     /* were previously skipping */
6327                lookup_value != NULL,         /* success/failure indicator */
6328                save_lookup_value,            /* value to reset for string2 */
6329                &s,                           /* input pointer */
6330                &yield,                       /* output pointer */
6331                US"listextract",              /* condition type */
6332                &resetok))
6333         {
6334         case 1: goto EXPAND_FAILED;          /* when all is well, the */
6335         case 2: goto EXPAND_FAILED_CURLY;    /* returned value is 0 */
6336         }
6337
6338       /* All done - restore numerical variables. */
6339
6340       restore_expand_strings(save_expand_nmax, save_expand_nstring,
6341         save_expand_nlength);
6342
6343       continue;
6344       }
6345
6346 #ifndef DISABLE_TLS
6347     case EITEM_CERTEXTRACT:
6348       {
6349       uschar *save_lookup_value = lookup_value;
6350       uschar *sub[2];
6351       int save_expand_nmax =
6352         save_expand_strings(save_expand_nstring, save_expand_nlength);
6353
6354       /* Read the field argument */
6355       while (isspace(*s)) s++;
6356       if (*s != '{')                                    /*}*/
6357         {
6358         expand_string_message = US"missing '{' for field arg of certextract";
6359         goto EXPAND_FAILED_CURLY;
6360         }
6361       sub[0] = expand_string_internal(s+1, TRUE, &s, skipping, TRUE, &resetok);
6362       if (!sub[0])     goto EXPAND_FAILED;              /*{*/
6363       if (*s++ != '}')
6364         {
6365         expand_string_message = US"missing '}' closing field arg of certextract";
6366         goto EXPAND_FAILED_CURLY;
6367         }
6368       /* strip spaces fore & aft */
6369       {
6370       int len;
6371       uschar *p = sub[0];
6372
6373       while (isspace(*p)) p++;
6374       sub[0] = p;
6375
6376       len = Ustrlen(p);
6377       while (len > 0 && isspace(p[len-1])) len--;
6378       p[len] = 0;
6379       }
6380
6381       /* inspect the cert argument */
6382       while (isspace(*s)) s++;
6383       if (*s != '{')                                    /*}*/
6384         {
6385         expand_string_message = US"missing '{' for cert variable arg of certextract";
6386         goto EXPAND_FAILED_CURLY;
6387         }
6388       if (*++s != '$')
6389         {
6390         expand_string_message = US"second argument of \"certextract\" must "
6391           "be a certificate variable";
6392         goto EXPAND_FAILED;
6393         }
6394       sub[1] = expand_string_internal(s+1, TRUE, &s, skipping, FALSE, &resetok);
6395       if (!sub[1])     goto EXPAND_FAILED;              /*{*/
6396       if (*s++ != '}')
6397         {
6398         expand_string_message = US"missing '}' closing cert variable arg of certextract";
6399         goto EXPAND_FAILED_CURLY;
6400         }
6401
6402       if (skipping)
6403         lookup_value = NULL;
6404       else
6405         {
6406         lookup_value = expand_getcertele(sub[0], sub[1]);
6407         if (*expand_string_message) goto EXPAND_FAILED;
6408         }
6409       switch(process_yesno(
6410                skipping,                     /* were previously skipping */
6411                lookup_value != NULL,         /* success/failure indicator */
6412                save_lookup_value,            /* value to reset for string2 */
6413                &s,                           /* input pointer */
6414                &yield,                       /* output pointer */
6415                US"certextract",              /* condition type */
6416                &resetok))
6417         {
6418         case 1: goto EXPAND_FAILED;          /* when all is well, the */
6419         case 2: goto EXPAND_FAILED_CURLY;    /* returned value is 0 */
6420         }
6421
6422       restore_expand_strings(save_expand_nmax, save_expand_nstring,
6423         save_expand_nlength);
6424       continue;
6425       }
6426 #endif  /*DISABLE_TLS*/
6427
6428     /* Handle list operations */
6429
6430     case EITEM_FILTER:
6431     case EITEM_MAP:
6432     case EITEM_REDUCE:
6433       {
6434       int sep = 0;
6435       int save_ptr = gstring_length(yield);
6436       uschar outsep[2] = { '\0', '\0' };
6437       const uschar *list, *expr, *temp;
6438       uschar *save_iterate_item = iterate_item;
6439       uschar *save_lookup_value = lookup_value;
6440
6441       while (isspace(*s)) s++;
6442       if (*s++ != '{')
6443         {
6444         expand_string_message =
6445           string_sprintf("missing '{' for first arg of %s", name);
6446         goto EXPAND_FAILED_CURLY;
6447         }
6448
6449       if (!(list = expand_string_internal(s, TRUE, &s, skipping, TRUE, &resetok)))
6450         goto EXPAND_FAILED;
6451       if (*s++ != '}')
6452         {
6453         expand_string_message =
6454           string_sprintf("missing '}' closing first arg of %s", name);
6455         goto EXPAND_FAILED_CURLY;
6456         }
6457
6458       if (item_type == EITEM_REDUCE)
6459         {
6460         uschar * t;
6461         while (isspace(*s)) s++;
6462         if (*s++ != '{')
6463           {
6464           expand_string_message = US"missing '{' for second arg of reduce";
6465           goto EXPAND_FAILED_CURLY;
6466           }
6467         t = expand_string_internal(s, TRUE, &s, skipping, TRUE, &resetok);
6468         if (!t) goto EXPAND_FAILED;
6469         lookup_value = t;
6470         if (*s++ != '}')
6471           {
6472           expand_string_message = US"missing '}' closing second arg of reduce";
6473           goto EXPAND_FAILED_CURLY;
6474           }
6475         }
6476
6477       while (isspace(*s)) s++;
6478       if (*s++ != '{')
6479         {
6480         expand_string_message =
6481           string_sprintf("missing '{' for last arg of %s", name);
6482         goto EXPAND_FAILED_CURLY;
6483         }
6484
6485       expr = s;
6486
6487       /* For EITEM_FILTER, call eval_condition once, with result discarded (as
6488       if scanning a "false" part). This allows us to find the end of the
6489       condition, because if the list is empty, we won't actually evaluate the
6490       condition for real. For EITEM_MAP and EITEM_REDUCE, do the same, using
6491       the normal internal expansion function. */
6492
6493       if (item_type == EITEM_FILTER)
6494         {
6495         if ((temp = eval_condition(expr, &resetok, NULL)))
6496           s = temp;
6497         }
6498       else
6499         temp = expand_string_internal(s, TRUE, &s, TRUE, TRUE, &resetok);
6500
6501       if (!temp)
6502         {
6503         expand_string_message = string_sprintf("%s inside \"%s\" item",
6504           expand_string_message, name);
6505         goto EXPAND_FAILED;
6506         }
6507
6508       while (isspace(*s)) s++;
6509       if (*s++ != '}')
6510         {                                               /*{*/
6511         expand_string_message = string_sprintf("missing } at end of condition "
6512           "or expression inside \"%s\"; could be an unquoted } in the content",
6513           name);
6514         goto EXPAND_FAILED;
6515         }
6516
6517       while (isspace(*s)) s++;                          /*{*/
6518       if (*s++ != '}')
6519         {                                               /*{*/
6520         expand_string_message = string_sprintf("missing } at end of \"%s\"",
6521           name);
6522         goto EXPAND_FAILED;
6523         }
6524
6525       /* If we are skipping, we can now just move on to the next item. When
6526       processing for real, we perform the iteration. */
6527
6528       if (skipping) continue;
6529       while ((iterate_item = string_nextinlist(&list, &sep, NULL, 0)))
6530         {
6531         *outsep = (uschar)sep;      /* Separator as a string */
6532
6533         DEBUG(D_expand) debug_printf_indent("%s: $item = '%s'  $value = '%s'\n",
6534                           name, iterate_item, lookup_value);
6535
6536         if (item_type == EITEM_FILTER)
6537           {
6538           BOOL condresult;
6539           if (!eval_condition(expr, &resetok, &condresult))
6540             {
6541             iterate_item = save_iterate_item;
6542             lookup_value = save_lookup_value;
6543             expand_string_message = string_sprintf("%s inside \"%s\" condition",
6544               expand_string_message, name);
6545             goto EXPAND_FAILED;
6546             }
6547           DEBUG(D_expand) debug_printf_indent("%s: condition is %s\n", name,
6548             condresult? "true":"false");
6549           if (condresult)
6550             temp = iterate_item;    /* TRUE => include this item */
6551           else
6552             continue;               /* FALSE => skip this item */
6553           }
6554
6555         /* EITEM_MAP and EITEM_REDUCE */
6556
6557         else
6558           {
6559           uschar * t = expand_string_internal(expr, TRUE, NULL, skipping, TRUE, &resetok);
6560           temp = t;
6561           if (!temp)
6562             {
6563             iterate_item = save_iterate_item;
6564             expand_string_message = string_sprintf("%s inside \"%s\" item",
6565               expand_string_message, name);
6566             goto EXPAND_FAILED;
6567             }
6568           if (item_type == EITEM_REDUCE)
6569             {
6570             lookup_value = t;         /* Update the value of $value */
6571             continue;                 /* and continue the iteration */
6572             }
6573           }
6574
6575         /* We reach here for FILTER if the condition is true, always for MAP,
6576         and never for REDUCE. The value in "temp" is to be added to the output
6577         list that is being created, ensuring that any occurrences of the
6578         separator character are doubled. Unless we are dealing with the first
6579         item of the output list, add in a space if the new item begins with the
6580         separator character, or is an empty string. */
6581
6582         if (  yield && yield->ptr != save_ptr
6583            && (temp[0] == *outsep || temp[0] == 0))
6584           yield = string_catn(yield, US" ", 1);
6585
6586         /* Add the string in "temp" to the output list that we are building,
6587         This is done in chunks by searching for the separator character. */
6588
6589         for (;;)
6590           {
6591           size_t seglen = Ustrcspn(temp, outsep);
6592
6593           yield = string_catn(yield, temp, seglen + 1);
6594
6595           /* If we got to the end of the string we output one character
6596           too many; backup and end the loop. Otherwise arrange to double the
6597           separator. */
6598
6599           if (temp[seglen] == '\0') { yield->ptr--; break; }
6600           yield = string_catn(yield, outsep, 1);
6601           temp += seglen + 1;
6602           }
6603
6604         /* Output a separator after the string: we will remove the redundant
6605         final one at the end. */
6606
6607         yield = string_catn(yield, outsep, 1);
6608         }   /* End of iteration over the list loop */
6609
6610       /* REDUCE has generated no output above: output the final value of
6611       $value. */
6612
6613       if (item_type == EITEM_REDUCE)
6614         {
6615         yield = string_cat(yield, lookup_value);
6616         lookup_value = save_lookup_value;  /* Restore $value */
6617         }
6618
6619       /* FILTER and MAP generate lists: if they have generated anything, remove
6620       the redundant final separator. Even though an empty item at the end of a
6621       list does not count, this is tidier. */
6622
6623       else if (yield && yield->ptr != save_ptr) yield->ptr--;
6624
6625       /* Restore preserved $item */
6626
6627       iterate_item = save_iterate_item;
6628       continue;
6629       }
6630
6631     case EITEM_SORT:
6632       {
6633       int cond_type;
6634       int sep = 0;
6635       const uschar *srclist, *cmp, *xtract;
6636       uschar * opname, * srcitem;
6637       const uschar *dstlist = NULL, *dstkeylist = NULL;
6638       uschar * tmp;
6639       uschar *save_iterate_item = iterate_item;
6640
6641       while (isspace(*s)) s++;
6642       if (*s++ != '{')
6643         {
6644         expand_string_message = US"missing '{' for list arg of sort";
6645         goto EXPAND_FAILED_CURLY;
6646         }
6647
6648       srclist = expand_string_internal(s, TRUE, &s, skipping, TRUE, &resetok);
6649       if (!srclist) goto EXPAND_FAILED;
6650       if (*s++ != '}')
6651         {
6652         expand_string_message = US"missing '}' closing list arg of sort";
6653         goto EXPAND_FAILED_CURLY;
6654         }
6655
6656       while (isspace(*s)) s++;
6657       if (*s++ != '{')
6658         {
6659         expand_string_message = US"missing '{' for comparator arg of sort";
6660         goto EXPAND_FAILED_CURLY;
6661         }
6662
6663       cmp = expand_string_internal(s, TRUE, &s, skipping, FALSE, &resetok);
6664       if (!cmp) goto EXPAND_FAILED;
6665       if (*s++ != '}')
6666         {
6667         expand_string_message = US"missing '}' closing comparator arg of sort";
6668         goto EXPAND_FAILED_CURLY;
6669         }
6670
6671       if ((cond_type = identify_operator(&cmp, &opname)) == -1)
6672         {
6673         if (!expand_string_message)
6674           expand_string_message = string_sprintf("unknown condition \"%s\"", s);
6675         goto EXPAND_FAILED;
6676         }
6677       switch(cond_type)
6678         {
6679         case ECOND_NUM_L: case ECOND_NUM_LE:
6680         case ECOND_NUM_G: case ECOND_NUM_GE:
6681         case ECOND_STR_GE: case ECOND_STR_GEI: case ECOND_STR_GT: case ECOND_STR_GTI:
6682         case ECOND_STR_LE: case ECOND_STR_LEI: case ECOND_STR_LT: case ECOND_STR_LTI:
6683           break;
6684
6685         default:
6686           expand_string_message = US"comparator not handled for sort";
6687           goto EXPAND_FAILED;
6688         }
6689
6690       while (isspace(*s)) s++;
6691       if (*s++ != '{')
6692         {
6693         expand_string_message = US"missing '{' for extractor arg of sort";
6694         goto EXPAND_FAILED_CURLY;
6695         }
6696
6697       xtract = s;
6698       if (!(tmp = expand_string_internal(s, TRUE, &s, TRUE, TRUE, &resetok)))
6699         goto EXPAND_FAILED;
6700       xtract = string_copyn(xtract, s - xtract);
6701
6702       if (*s++ != '}')
6703         {
6704         expand_string_message = US"missing '}' closing extractor arg of sort";
6705         goto EXPAND_FAILED_CURLY;
6706         }
6707                                                         /*{*/
6708       if (*s++ != '}')
6709         {                                               /*{*/
6710         expand_string_message = US"missing } at end of \"sort\"";
6711         goto EXPAND_FAILED;
6712         }
6713
6714       if (skipping) continue;
6715
6716       while ((srcitem = string_nextinlist(&srclist, &sep, NULL, 0)))
6717         {
6718         uschar * srcfield, * dstitem;
6719         gstring * newlist = NULL;
6720         gstring * newkeylist = NULL;
6721
6722         DEBUG(D_expand) debug_printf_indent("%s: $item = \"%s\"\n", name, srcitem);
6723
6724         /* extract field for comparisons */
6725         iterate_item = srcitem;
6726         if (  !(srcfield = expand_string_internal(xtract, FALSE, NULL, FALSE,
6727                                           TRUE, &resetok))
6728            || !*srcfield)
6729           {
6730           expand_string_message = string_sprintf(
6731               "field-extract in sort: \"%s\"", xtract);
6732           goto EXPAND_FAILED;
6733           }
6734
6735         /* Insertion sort */
6736
6737         /* copy output list until new-item < list-item */
6738         while ((dstitem = string_nextinlist(&dstlist, &sep, NULL, 0)))
6739           {
6740           uschar * dstfield;
6741
6742           /* field for comparison */
6743           if (!(dstfield = string_nextinlist(&dstkeylist, &sep, NULL, 0)))
6744             goto sort_mismatch;
6745
6746           /* String-comparator names start with a letter; numeric names do not */
6747
6748           if (sortsbefore(cond_type, isalpha(opname[0]),
6749               srcfield, dstfield))
6750             {
6751             /* New-item sorts before this dst-item.  Append new-item,
6752             then dst-item, then remainder of dst list. */
6753
6754             newlist = string_append_listele(newlist, sep, srcitem);
6755             newkeylist = string_append_listele(newkeylist, sep, srcfield);
6756             srcitem = NULL;
6757
6758             newlist = string_append_listele(newlist, sep, dstitem);
6759             newkeylist = string_append_listele(newkeylist, sep, dstfield);
6760
6761 /*XXX why field-at-a-time copy?  Why not just dup the rest of the list? */
6762             while ((dstitem = string_nextinlist(&dstlist, &sep, NULL, 0)))
6763               {
6764               if (!(dstfield = string_nextinlist(&dstkeylist, &sep, NULL, 0)))
6765                 goto sort_mismatch;
6766               newlist = string_append_listele(newlist, sep, dstitem);
6767               newkeylist = string_append_listele(newkeylist, sep, dstfield);
6768               }
6769
6770             break;
6771             }
6772
6773           newlist = string_append_listele(newlist, sep, dstitem);
6774           newkeylist = string_append_listele(newkeylist, sep, dstfield);
6775           }
6776
6777         /* If we ran out of dstlist without consuming srcitem, append it */
6778         if (srcitem)
6779           {
6780           newlist = string_append_listele(newlist, sep, srcitem);
6781           newkeylist = string_append_listele(newkeylist, sep, srcfield);
6782           }
6783
6784         dstlist = newlist->s;
6785         dstkeylist = newkeylist->s;
6786
6787         DEBUG(D_expand) debug_printf_indent("%s: dstlist = \"%s\"\n", name, dstlist);
6788         DEBUG(D_expand) debug_printf_indent("%s: dstkeylist = \"%s\"\n", name, dstkeylist);
6789         }
6790
6791       if (dstlist)
6792         yield = string_cat(yield, dstlist);
6793
6794       /* Restore preserved $item */
6795       iterate_item = save_iterate_item;
6796       continue;
6797
6798       sort_mismatch:
6799         expand_string_message = US"Internal error in sort (list mismatch)";
6800         goto EXPAND_FAILED;
6801       }
6802
6803
6804     /* If ${dlfunc } support is configured, handle calling dynamically-loaded
6805     functions, unless locked out at this time. Syntax is ${dlfunc{file}{func}}
6806     or ${dlfunc{file}{func}{arg}} or ${dlfunc{file}{func}{arg1}{arg2}} or up to
6807     a maximum of EXPAND_DLFUNC_MAX_ARGS arguments (defined below). */
6808
6809     #define EXPAND_DLFUNC_MAX_ARGS 8
6810
6811     case EITEM_DLFUNC:
6812 #ifndef EXPAND_DLFUNC
6813       expand_string_message = US"\"${dlfunc\" encountered, but this facility "  /*}*/
6814         "is not included in this binary";
6815       goto EXPAND_FAILED;
6816
6817 #else   /* EXPAND_DLFUNC */
6818       {
6819       tree_node *t;
6820       exim_dlfunc_t *func;
6821       uschar *result;
6822       int status, argc;
6823       uschar *argv[EXPAND_DLFUNC_MAX_ARGS + 3];
6824
6825       if ((expand_forbid & RDO_DLFUNC) != 0)
6826         {
6827         expand_string_message =
6828           US"dynamically-loaded functions are not permitted";
6829         goto EXPAND_FAILED;
6830         }
6831
6832       switch(read_subs(argv, EXPAND_DLFUNC_MAX_ARGS + 2, 2, &s, skipping,
6833            TRUE, US"dlfunc", &resetok))
6834         {
6835         case 1: goto EXPAND_FAILED_CURLY;
6836         case 2:
6837         case 3: goto EXPAND_FAILED;
6838         }
6839
6840       /* If skipping, we don't actually do anything */
6841
6842       if (skipping) continue;
6843
6844       /* Look up the dynamically loaded object handle in the tree. If it isn't
6845       found, dlopen() the file and put the handle in the tree for next time. */
6846
6847       if (!(t = tree_search(dlobj_anchor, argv[0])))
6848         {
6849         void *handle = dlopen(CS argv[0], RTLD_LAZY);
6850         if (!handle)
6851           {
6852           expand_string_message = string_sprintf("dlopen \"%s\" failed: %s",
6853             argv[0], dlerror());
6854           log_write(0, LOG_MAIN|LOG_PANIC, "%s", expand_string_message);
6855           goto EXPAND_FAILED;
6856           }
6857         t = store_get_perm(sizeof(tree_node) + Ustrlen(argv[0]), is_tainted(argv[0]));
6858         Ustrcpy(t->name, argv[0]);
6859         t->data.ptr = handle;
6860         (void)tree_insertnode(&dlobj_anchor, t);
6861         }
6862
6863       /* Having obtained the dynamically loaded object handle, look up the
6864       function pointer. */
6865
6866       if (!(func = (exim_dlfunc_t *)dlsym(t->data.ptr, CS argv[1])))
6867         {
6868         expand_string_message = string_sprintf("dlsym \"%s\" in \"%s\" failed: "
6869           "%s", argv[1], argv[0], dlerror());
6870         log_write(0, LOG_MAIN|LOG_PANIC, "%s", expand_string_message);
6871         goto EXPAND_FAILED;
6872         }
6873
6874       /* Call the function and work out what to do with the result. If it
6875       returns OK, we have a replacement string; if it returns DEFER then
6876       expansion has failed in a non-forced manner; if it returns FAIL then
6877       failure was forced; if it returns ERROR or any other value there's a
6878       problem, so panic slightly. In any case, assume that the function has
6879       side-effects on the store that must be preserved. */
6880
6881       resetok = FALSE;
6882       result = NULL;
6883       for (argc = 0; argv[argc]; argc++);
6884       status = func(&result, argc - 2, &argv[2]);
6885       if(status == OK)
6886         {
6887         if (!result) result = US"";
6888         yield = string_cat(yield, result);
6889         continue;
6890         }
6891       else
6892         {
6893         expand_string_message = result ? result : US"(no message)";
6894         if (status == FAIL_FORCED)
6895           f.expand_string_forcedfail = TRUE;
6896         else if (status != FAIL)
6897           log_write(0, LOG_MAIN|LOG_PANIC, "dlfunc{%s}{%s} failed (%d): %s",
6898               argv[0], argv[1], status, expand_string_message);
6899         goto EXPAND_FAILED;
6900         }
6901       }
6902 #endif /* EXPAND_DLFUNC */
6903
6904     case EITEM_ENV:     /* ${env {name} {val_if_found} {val_if_unfound}} */
6905       {
6906       uschar * key;
6907       uschar *save_lookup_value = lookup_value;
6908
6909       while (isspace(*s)) s++;
6910       if (*s != '{')                                    /*}*/
6911         goto EXPAND_FAILED;
6912
6913       key = expand_string_internal(s+1, TRUE, &s, skipping, TRUE, &resetok);
6914       if (!key) goto EXPAND_FAILED;                     /*{*/
6915       if (*s++ != '}')
6916         {
6917         expand_string_message = US"missing '{' for name arg of env";
6918         goto EXPAND_FAILED_CURLY;
6919         }
6920
6921       lookup_value = US getenv(CS key);
6922
6923       switch(process_yesno(
6924                skipping,                     /* were previously skipping */
6925                lookup_value != NULL,         /* success/failure indicator */
6926                save_lookup_value,            /* value to reset for string2 */
6927                &s,                           /* input pointer */
6928                &yield,                       /* output pointer */
6929                US"env",                      /* condition type */
6930                &resetok))
6931         {
6932         case 1: goto EXPAND_FAILED;          /* when all is well, the */
6933         case 2: goto EXPAND_FAILED_CURLY;    /* returned value is 0 */
6934         }
6935       continue;
6936       }
6937
6938 #ifdef EXPERIMENTAL_SRS_NATIVE
6939     case EITEM_SRS_ENCODE:
6940       /* ${srs_encode {secret} {return_path} {orig_domain}} */
6941       {
6942       uschar * sub[3];
6943       uschar cksum[4];
6944
6945       switch (read_subs(sub, 3, 3, CUSS &s, skipping, TRUE, name, &resetok))
6946         {
6947         case 1: goto EXPAND_FAILED_CURLY;
6948         case 2:
6949         case 3: goto EXPAND_FAILED;
6950         }
6951
6952       yield = string_catn(yield, US"SRS0=", 5);
6953
6954       /* ${l_4:${hmac{md5}{SRS_SECRET}{${lc:$return_path}}}}= */
6955       hmac_md5(sub[0], string_copylc(sub[1]), cksum, sizeof(cksum));
6956       yield = string_catn(yield, cksum, sizeof(cksum));
6957       yield = string_catn(yield, US"=", 1);
6958
6959       /* ${base32:${eval:$tod_epoch/86400&0x3ff}}= */
6960         {
6961         struct timeval now;
6962         unsigned long i;
6963         gstring * g = NULL;
6964
6965         gettimeofday(&now, NULL);
6966         for (unsigned long i = (now.tv_sec / 86400) & 0x3ff; i; i >>= 5)
6967           g = string_catn(g, &base32_chars[i & 0x1f], 1);
6968         if (g) while (g->ptr > 0)
6969           yield = string_catn(yield, &g->s[--g->ptr], 1);
6970         }
6971       yield = string_catn(yield, US"=", 1);
6972
6973       /* ${domain:$return_path}=${local_part:$return_path} */
6974         {
6975         int start, end, domain;
6976         uschar * t = parse_extract_address(sub[1], &expand_string_message,
6977                                           &start, &end, &domain, FALSE);
6978         if (!t)
6979           goto EXPAND_FAILED;
6980
6981         if (domain > 0) yield = string_cat(yield, t + domain);
6982         yield = string_catn(yield, US"=", 1);
6983         yield = domain > 0
6984           ? string_catn(yield, t, domain - 1) : string_cat(yield, t);
6985         }
6986
6987       /* @$original_domain */
6988       yield = string_catn(yield, US"@", 1);
6989       yield = string_cat(yield, sub[2]);
6990       continue;
6991       }
6992 #endif /*EXPERIMENTAL_SRS_NATIVE*/
6993     }   /* EITEM_* switch */
6994
6995   /* Control reaches here if the name is not recognized as one of the more
6996   complicated expansion items. Check for the "operator" syntax (name terminated
6997   by a colon). Some of the operators have arguments, separated by _ from the
6998   name. */
6999
7000   if (*s == ':')
7001     {
7002     int c;
7003     uschar *arg = NULL;
7004     uschar *sub;
7005 #ifndef DISABLE_TLS
7006     var_entry *vp = NULL;
7007 #endif
7008
7009     /* Owing to an historical mis-design, an underscore may be part of the
7010     operator name, or it may introduce arguments.  We therefore first scan the
7011     table of names that contain underscores. If there is no match, we cut off
7012     the arguments and then scan the main table. */
7013
7014     if ((c = chop_match(name, op_table_underscore,
7015                         nelem(op_table_underscore))) < 0)
7016       {
7017       if ((arg = Ustrchr(name, '_')))
7018         *arg = 0;
7019       if ((c = chop_match(name, op_table_main, nelem(op_table_main))) >= 0)
7020         c += nelem(op_table_underscore);
7021       if (arg) *arg++ = '_';            /* Put back for error messages */
7022       }
7023
7024     /* Deal specially with operators that might take a certificate variable
7025     as we do not want to do the usual expansion. For most, expand the string.*/
7026     switch(c)
7027       {
7028 #ifndef DISABLE_TLS
7029       case EOP_MD5:
7030       case EOP_SHA1:
7031       case EOP_SHA256:
7032       case EOP_BASE64:
7033         if (s[1] == '$')
7034           {
7035           const uschar * s1 = s;
7036           sub = expand_string_internal(s+2, TRUE, &s1, skipping,
7037                   FALSE, &resetok);
7038           if (!sub)       goto EXPAND_FAILED;           /*{*/
7039           if (*s1 != '}')
7040             {
7041             expand_string_message =
7042               string_sprintf("missing '}' closing cert arg of %s", name);
7043             goto EXPAND_FAILED_CURLY;
7044             }
7045           if ((vp = find_var_ent(sub)) && vp->type == vtype_cert)
7046             {
7047             s = s1+1;
7048             break;
7049             }
7050           vp = NULL;
7051           }
7052         /*FALLTHROUGH*/
7053 #endif
7054       default:
7055         sub = expand_string_internal(s+1, TRUE, &s, skipping, TRUE, &resetok);
7056         if (!sub) goto EXPAND_FAILED;
7057         s++;
7058         break;
7059       }
7060
7061     /* If we are skipping, we don't need to perform the operation at all.
7062     This matters for operations like "mask", because the data may not be
7063     in the correct format when skipping. For example, the expression may test
7064     for the existence of $sender_host_address before trying to mask it. For
7065     other operations, doing them may not fail, but it is a waste of time. */
7066
7067     if (skipping && c >= 0) continue;
7068
7069     /* Otherwise, switch on the operator type */
7070
7071     switch(c)
7072       {
7073       case EOP_BASE32:
7074         {
7075         uschar *t;
7076         unsigned long int n = Ustrtoul(sub, &t, 10);
7077         gstring * g = NULL;
7078
7079         if (*t != 0)
7080           {
7081           expand_string_message = string_sprintf("argument for base32 "
7082             "operator is \"%s\", which is not a decimal number", sub);
7083           goto EXPAND_FAILED;
7084           }
7085         for ( ; n; n >>= 5)
7086           g = string_catn(g, &base32_chars[n & 0x1f], 1);
7087
7088         if (g) while (g->ptr > 0) yield = string_catn(yield, &g->s[--g->ptr], 1);
7089         continue;
7090         }
7091
7092       case EOP_BASE32D:
7093         {
7094         uschar *tt = sub;
7095         unsigned long int n = 0;
7096         while (*tt)
7097           {
7098           uschar * t = Ustrchr(base32_chars, *tt++);
7099           if (!t)
7100             {
7101             expand_string_message = string_sprintf("argument for base32d "
7102               "operator is \"%s\", which is not a base 32 number", sub);
7103             goto EXPAND_FAILED;
7104             }
7105           n = n * 32 + (t - base32_chars);
7106           }
7107         yield = string_fmt_append(yield, "%ld", n);
7108         continue;
7109         }
7110
7111       case EOP_BASE62:
7112         {
7113         uschar *t;
7114         unsigned long int n = Ustrtoul(sub, &t, 10);
7115         if (*t != 0)
7116           {
7117           expand_string_message = string_sprintf("argument for base62 "
7118             "operator is \"%s\", which is not a decimal number", sub);
7119           goto EXPAND_FAILED;
7120           }
7121         yield = string_cat(yield, string_base62(n));
7122         continue;
7123         }
7124
7125       /* Note that for Darwin and Cygwin, BASE_62 actually has the value 36 */
7126
7127       case EOP_BASE62D:
7128         {
7129         uschar *tt = sub;
7130         unsigned long int n = 0;
7131         while (*tt != 0)
7132           {
7133           uschar *t = Ustrchr(base62_chars, *tt++);
7134           if (!t)
7135             {
7136             expand_string_message = string_sprintf("argument for base62d "
7137               "operator is \"%s\", which is not a base %d number", sub,
7138               BASE_62);
7139             goto EXPAND_FAILED;
7140             }
7141           n = n * BASE_62 + (t - base62_chars);
7142           }
7143         yield = string_fmt_append(yield, "%ld", n);
7144         continue;
7145         }
7146
7147       case EOP_BLESS:
7148         /* This is purely for the convenience of the test harness.  Do not enable
7149         it otherwise as it defeats the taint-checking security. */
7150
7151         if (f.running_in_test_harness)
7152           yield = string_cat(yield, is_tainted(sub)
7153                                     ? string_copy_taint(sub, FALSE) : sub);
7154         else
7155           {
7156           DEBUG(D_expand) debug_printf_indent("bless operator not supported\n");
7157           yield = string_cat(yield, sub);
7158           }
7159         continue;
7160
7161       case EOP_EXPAND:
7162         {
7163         uschar *expanded = expand_string_internal(sub, FALSE, NULL, skipping, TRUE, &resetok);
7164         if (!expanded)
7165           {
7166           expand_string_message =
7167             string_sprintf("internal expansion of \"%s\" failed: %s", sub,
7168               expand_string_message);
7169           goto EXPAND_FAILED;
7170           }
7171         yield = string_cat(yield, expanded);
7172         continue;
7173         }
7174
7175       case EOP_LC:
7176         {
7177         int count = 0;
7178         uschar *t = sub - 1;
7179         while (*(++t) != 0) { *t = tolower(*t); count++; }
7180         yield = string_catn(yield, sub, count);
7181         continue;
7182         }
7183
7184       case EOP_UC:
7185         {
7186         int count = 0;
7187         uschar *t = sub - 1;
7188         while (*(++t) != 0) { *t = toupper(*t); count++; }
7189         yield = string_catn(yield, sub, count);
7190         continue;
7191         }
7192
7193       case EOP_MD5:
7194 #ifndef DISABLE_TLS
7195         if (vp && *(void **)vp->value)
7196           {
7197           uschar * cp = tls_cert_fprt_md5(*(void **)vp->value);
7198           yield = string_cat(yield, cp);
7199           }
7200         else
7201 #endif
7202           {
7203           md5 base;
7204           uschar digest[16];
7205           md5_start(&base);
7206           md5_end(&base, sub, Ustrlen(sub), digest);
7207           for (int j = 0; j < 16; j++)
7208             yield = string_fmt_append(yield, "%02x", digest[j]);
7209           }
7210         continue;
7211
7212       case EOP_SHA1:
7213 #ifndef DISABLE_TLS
7214         if (vp && *(void **)vp->value)
7215           {
7216           uschar * cp = tls_cert_fprt_sha1(*(void **)vp->value);
7217           yield = string_cat(yield, cp);
7218           }
7219         else
7220 #endif
7221           {
7222           hctx h;
7223           uschar digest[20];
7224           sha1_start(&h);
7225           sha1_end(&h, sub, Ustrlen(sub), digest);
7226           for (int j = 0; j < 20; j++)
7227             yield = string_fmt_append(yield, "%02X", digest[j]);
7228           }
7229         continue;
7230
7231       case EOP_SHA2:
7232       case EOP_SHA256:
7233 #ifdef EXIM_HAVE_SHA2
7234         if (vp && *(void **)vp->value)
7235           if (c == EOP_SHA256)
7236             yield = string_cat(yield, tls_cert_fprt_sha256(*(void **)vp->value));
7237           else
7238             expand_string_message = US"sha2_N not supported with certificates";
7239         else
7240           {
7241           hctx h;
7242           blob b;
7243           hashmethod m = !arg ? HASH_SHA2_256
7244             : Ustrcmp(arg, "256") == 0 ? HASH_SHA2_256
7245             : Ustrcmp(arg, "384") == 0 ? HASH_SHA2_384
7246             : Ustrcmp(arg, "512") == 0 ? HASH_SHA2_512
7247             : HASH_BADTYPE;
7248
7249           if (m == HASH_BADTYPE || !exim_sha_init(&h, m))
7250             {
7251             expand_string_message = US"unrecognised sha2 variant";
7252             goto EXPAND_FAILED;
7253             }
7254
7255           exim_sha_update(&h, sub, Ustrlen(sub));
7256           exim_sha_finish(&h, &b);
7257           while (b.len-- > 0)
7258             yield = string_fmt_append(yield, "%02X", *b.data++);
7259           }
7260 #else
7261           expand_string_message = US"sha256 only supported with TLS";
7262 #endif
7263         continue;
7264
7265       case EOP_SHA3:
7266 #ifdef EXIM_HAVE_SHA3
7267         {
7268         hctx h;
7269         blob b;
7270         hashmethod m = !arg ? HASH_SHA3_256
7271           : Ustrcmp(arg, "224") == 0 ? HASH_SHA3_224
7272           : Ustrcmp(arg, "256") == 0 ? HASH_SHA3_256
7273           : Ustrcmp(arg, "384") == 0 ? HASH_SHA3_384
7274           : Ustrcmp(arg, "512") == 0 ? HASH_SHA3_512
7275           : HASH_BADTYPE;
7276
7277         if (m == HASH_BADTYPE || !exim_sha_init(&h, m))
7278           {
7279           expand_string_message = US"unrecognised sha3 variant";
7280           goto EXPAND_FAILED;
7281           }
7282
7283         exim_sha_update(&h, sub, Ustrlen(sub));
7284         exim_sha_finish(&h, &b);
7285         while (b.len-- > 0)
7286           yield = string_fmt_append(yield, "%02X", *b.data++);
7287         }
7288         continue;
7289 #else
7290         expand_string_message = US"sha3 only supported with GnuTLS 3.5.0 + or OpenSSL 1.1.1 +";
7291         goto EXPAND_FAILED;
7292 #endif
7293
7294       /* Convert hex encoding to base64 encoding */
7295
7296       case EOP_HEX2B64:
7297         {
7298         int c = 0;
7299         int b = -1;
7300         uschar *in = sub;
7301         uschar *out = sub;
7302         uschar *enc;
7303
7304         for (enc = sub; *enc; enc++)
7305           {
7306           if (!isxdigit(*enc))
7307             {
7308             expand_string_message = string_sprintf("\"%s\" is not a hex "
7309               "string", sub);
7310             goto EXPAND_FAILED;
7311             }
7312           c++;
7313           }
7314
7315         if ((c & 1) != 0)
7316           {
7317           expand_string_message = string_sprintf("\"%s\" contains an odd "
7318             "number of characters", sub);
7319           goto EXPAND_FAILED;
7320           }
7321
7322         while ((c = *in++) != 0)
7323           {
7324           if (isdigit(c)) c -= '0';
7325           else c = toupper(c) - 'A' + 10;
7326           if (b == -1)
7327             b = c << 4;
7328           else
7329             {
7330             *out++ = b | c;
7331             b = -1;
7332             }
7333           }
7334
7335         enc = b64encode(CUS sub, out - sub);
7336         yield = string_cat(yield, enc);
7337         continue;
7338         }
7339
7340       /* Convert octets outside 0x21..0x7E to \xXX form */
7341
7342       case EOP_HEXQUOTE:
7343         {
7344         uschar *t = sub - 1;
7345         while (*(++t) != 0)
7346           {
7347           if (*t < 0x21 || 0x7E < *t)
7348             yield = string_fmt_append(yield, "\\x%02x", *t);
7349           else
7350             yield = string_catn(yield, t, 1);
7351           }
7352         continue;
7353         }
7354
7355       /* count the number of list elements */
7356
7357       case EOP_LISTCOUNT:
7358         {
7359         int cnt = 0;
7360         int sep = 0;
7361         uschar buffer[256];
7362
7363         while (string_nextinlist(CUSS &sub, &sep, buffer, sizeof(buffer))) cnt++;
7364         yield = string_fmt_append(yield, "%d", cnt);
7365         continue;
7366         }
7367
7368       /* expand a named list given the name */
7369       /* handles nested named lists; requotes as colon-sep list */
7370
7371       case EOP_LISTNAMED:
7372         {
7373         tree_node *t = NULL;
7374         const uschar * list;
7375         int sep = 0;
7376         uschar * item;
7377         uschar * suffix = US"";
7378         BOOL needsep = FALSE;
7379         uschar buffer[256];
7380
7381         if (*sub == '+') sub++;
7382         if (!arg)               /* no-argument version */
7383           {
7384           if (!(t = tree_search(addresslist_anchor, sub)) &&
7385               !(t = tree_search(domainlist_anchor,  sub)) &&
7386               !(t = tree_search(hostlist_anchor,    sub)))
7387             t = tree_search(localpartlist_anchor, sub);
7388           }
7389         else switch(*arg)       /* specific list-type version */
7390           {
7391           case 'a': t = tree_search(addresslist_anchor,   sub); suffix = US"_a"; break;
7392           case 'd': t = tree_search(domainlist_anchor,    sub); suffix = US"_d"; break;
7393           case 'h': t = tree_search(hostlist_anchor,      sub); suffix = US"_h"; break;
7394           case 'l': t = tree_search(localpartlist_anchor, sub); suffix = US"_l"; break;
7395           default:
7396             expand_string_message = US"bad suffix on \"list\" operator";
7397             goto EXPAND_FAILED;
7398           }
7399
7400         if(!t)
7401           {
7402           expand_string_message = string_sprintf("\"%s\" is not a %snamed list",
7403             sub, !arg?""
7404               : *arg=='a'?"address "
7405               : *arg=='d'?"domain "
7406               : *arg=='h'?"host "
7407               : *arg=='l'?"localpart "
7408               : 0);
7409           goto EXPAND_FAILED;
7410           }
7411
7412         list = ((namedlist_block *)(t->data.ptr))->string;
7413
7414         while ((item = string_nextinlist(&list, &sep, buffer, sizeof(buffer))))
7415           {
7416           uschar * buf = US" : ";
7417           if (needsep)
7418             yield = string_catn(yield, buf, 3);
7419           else
7420             needsep = TRUE;
7421
7422           if (*item == '+')     /* list item is itself a named list */
7423             {
7424             uschar * sub = string_sprintf("${listnamed%s:%s}", suffix, item);
7425             item = expand_string_internal(sub, FALSE, NULL, FALSE, TRUE, &resetok);
7426             }
7427           else if (sep != ':')  /* item from non-colon-sep list, re-quote for colon list-separator */
7428             {
7429             char * cp;
7430             char tok[3];
7431             tok[0] = sep; tok[1] = ':'; tok[2] = 0;
7432             while ((cp= strpbrk(CCS item, tok)))
7433               {
7434               yield = string_catn(yield, item, cp - CS item);
7435               if (*cp++ == ':') /* colon in a non-colon-sep list item, needs doubling */
7436                 {
7437                 yield = string_catn(yield, US"::", 2);
7438                 item = US cp;
7439                 }
7440               else              /* sep in item; should already be doubled; emit once */
7441                 {
7442                 yield = string_catn(yield, US tok, 1);
7443                 if (*cp == sep) cp++;
7444                 item = US cp;
7445                 }
7446               }
7447             }
7448           yield = string_cat(yield, item);
7449           }
7450         continue;
7451         }
7452
7453       /* mask applies a mask to an IP address; for example the result of
7454       ${mask:131.111.10.206/28} is 131.111.10.192/28. */
7455
7456       case EOP_MASK:
7457         {
7458         int count;
7459         uschar *endptr;
7460         int binary[4];
7461         int mask, maskoffset;
7462         int type = string_is_ip_address(sub, &maskoffset);
7463         uschar buffer[64];
7464
7465         if (type == 0)
7466           {
7467           expand_string_message = string_sprintf("\"%s\" is not an IP address",
7468            sub);
7469           goto EXPAND_FAILED;
7470           }
7471
7472         if (maskoffset == 0)
7473           {
7474           expand_string_message = string_sprintf("missing mask value in \"%s\"",
7475             sub);
7476           goto EXPAND_FAILED;
7477           }
7478
7479         mask = Ustrtol(sub + maskoffset + 1, &endptr, 10);
7480
7481         if (*endptr != 0 || mask < 0 || mask > ((type == 4)? 32 : 128))
7482           {
7483           expand_string_message = string_sprintf("mask value too big in \"%s\"",
7484             sub);
7485           goto EXPAND_FAILED;
7486           }
7487
7488         /* Convert the address to binary integer(s) and apply the mask */
7489
7490         sub[maskoffset] = 0;
7491         count = host_aton(sub, binary);
7492         host_mask(count, binary, mask);
7493
7494         /* Convert to masked textual format and add to output. */
7495
7496         yield = string_catn(yield, buffer,
7497           host_nmtoa(count, binary, mask, buffer, '.'));
7498         continue;
7499         }
7500
7501       case EOP_IPV6NORM:
7502       case EOP_IPV6DENORM:
7503         {
7504         int type = string_is_ip_address(sub, NULL);
7505         int binary[4];
7506         uschar buffer[44];
7507
7508         switch (type)
7509           {
7510           case 6:
7511             (void) host_aton(sub, binary);
7512             break;
7513
7514           case 4:       /* convert to IPv4-mapped IPv6 */
7515             binary[0] = binary[1] = 0;
7516             binary[2] = 0x0000ffff;
7517             (void) host_aton(sub, binary+3);
7518             break;
7519
7520           case 0:
7521             expand_string_message =
7522               string_sprintf("\"%s\" is not an IP address", sub);
7523             goto EXPAND_FAILED;
7524           }
7525
7526         yield = string_catn(yield, buffer, c == EOP_IPV6NORM
7527                     ? ipv6_nmtoa(binary, buffer)
7528                     : host_nmtoa(4, binary, -1, buffer, ':')
7529                   );
7530         continue;
7531         }
7532
7533       case EOP_ADDRESS:
7534       case EOP_LOCAL_PART:
7535       case EOP_DOMAIN:
7536         {
7537         uschar * error;
7538         int start, end, domain;
7539         uschar * t = parse_extract_address(sub, &error, &start, &end, &domain,
7540           FALSE);
7541         if (t)
7542           if (c != EOP_DOMAIN)
7543             yield = c == EOP_LOCAL_PART && domain > 0
7544               ? string_catn(yield, t, domain - 1)
7545               : string_cat(yield, t);
7546           else if (domain > 0)
7547             yield = string_cat(yield, t + domain);
7548         continue;
7549         }
7550
7551       case EOP_ADDRESSES:
7552         {
7553         uschar outsep[2] = { ':', '\0' };
7554         uschar *address, *error;
7555         int save_ptr = gstring_length(yield);
7556         int start, end, domain;  /* Not really used */
7557
7558         while (isspace(*sub)) sub++;
7559         if (*sub == '>')
7560           if (*outsep = *++sub) ++sub;
7561           else
7562             {
7563             expand_string_message = string_sprintf("output separator "
7564               "missing in expanding ${addresses:%s}", --sub);
7565             goto EXPAND_FAILED;
7566             }
7567         f.parse_allow_group = TRUE;
7568
7569         for (;;)
7570           {
7571           uschar * p = parse_find_address_end(sub, FALSE);
7572           uschar saveend = *p;
7573           *p = '\0';
7574           address = parse_extract_address(sub, &error, &start, &end, &domain,
7575             FALSE);
7576           *p = saveend;
7577
7578           /* Add the address to the output list that we are building. This is
7579           done in chunks by searching for the separator character. At the
7580           start, unless we are dealing with the first address of the output
7581           list, add in a space if the new address begins with the separator
7582           character, or is an empty string. */
7583
7584           if (address)
7585             {
7586             if (yield && yield->ptr != save_ptr && address[0] == *outsep)
7587               yield = string_catn(yield, US" ", 1);
7588
7589             for (;;)
7590               {
7591               size_t seglen = Ustrcspn(address, outsep);
7592               yield = string_catn(yield, address, seglen + 1);
7593
7594               /* If we got to the end of the string we output one character
7595               too many. */
7596
7597               if (address[seglen] == '\0') { yield->ptr--; break; }
7598               yield = string_catn(yield, outsep, 1);
7599               address += seglen + 1;
7600               }
7601
7602             /* Output a separator after the string: we will remove the
7603             redundant final one at the end. */
7604
7605             yield = string_catn(yield, outsep, 1);
7606             }
7607
7608           if (saveend == '\0') break;
7609           sub = p + 1;
7610           }
7611
7612         /* If we have generated anything, remove the redundant final
7613         separator. */
7614
7615         if (yield && yield->ptr != save_ptr) yield->ptr--;
7616         f.parse_allow_group = FALSE;
7617         continue;
7618         }
7619
7620
7621       /* quote puts a string in quotes if it is empty or contains anything
7622       other than alphamerics, underscore, dot, or hyphen.
7623
7624       quote_local_part puts a string in quotes if RFC 2821/2822 requires it to
7625       be quoted in order to be a valid local part.
7626
7627       In both cases, newlines and carriage returns are converted into \n and \r
7628       respectively */
7629
7630       case EOP_QUOTE:
7631       case EOP_QUOTE_LOCAL_PART:
7632       if (!arg)
7633         {
7634         BOOL needs_quote = (*sub == 0);      /* TRUE for empty string */
7635         uschar *t = sub - 1;
7636
7637         if (c == EOP_QUOTE)
7638           {
7639           while (!needs_quote && *(++t) != 0)
7640             needs_quote = !isalnum(*t) && !strchr("_-.", *t);
7641           }
7642         else  /* EOP_QUOTE_LOCAL_PART */
7643           {
7644           while (!needs_quote && *(++t) != 0)
7645             needs_quote = !isalnum(*t) &&
7646               strchr("!#$%&'*+-/=?^_`{|}~", *t) == NULL &&
7647               (*t != '.' || t == sub || t[1] == 0);
7648           }
7649
7650         if (needs_quote)
7651           {
7652           yield = string_catn(yield, US"\"", 1);
7653           t = sub - 1;
7654           while (*(++t) != 0)
7655             {
7656             if (*t == '\n')
7657               yield = string_catn(yield, US"\\n", 2);
7658             else if (*t == '\r')
7659               yield = string_catn(yield, US"\\r", 2);
7660             else
7661               {
7662               if (*t == '\\' || *t == '"')
7663                 yield = string_catn(yield, US"\\", 1);
7664               yield = string_catn(yield, t, 1);
7665               }
7666             }
7667           yield = string_catn(yield, US"\"", 1);
7668           }
7669         else yield = string_cat(yield, sub);
7670         continue;
7671         }
7672
7673       /* quote_lookuptype does lookup-specific quoting */
7674
7675       else
7676         {
7677         int n;
7678         uschar *opt = Ustrchr(arg, '_');
7679
7680         if (opt) *opt++ = 0;
7681
7682         if ((n = search_findtype(arg, Ustrlen(arg))) < 0)
7683           {
7684           expand_string_message = search_error_message;
7685           goto EXPAND_FAILED;
7686           }
7687
7688         if (lookup_list[n]->quote)
7689           sub = (lookup_list[n]->quote)(sub, opt);
7690         else if (opt)
7691           sub = NULL;
7692
7693         if (!sub)
7694           {
7695           expand_string_message = string_sprintf(
7696             "\"%s\" unrecognized after \"${quote_%s\"",
7697             opt, arg);
7698           goto EXPAND_FAILED;
7699           }
7700
7701         yield = string_cat(yield, sub);
7702         continue;
7703         }
7704
7705       /* rx quote sticks in \ before any non-alphameric character so that
7706       the insertion works in a regular expression. */
7707
7708       case EOP_RXQUOTE:
7709         {
7710         uschar *t = sub - 1;
7711         while (*(++t) != 0)
7712           {
7713           if (!isalnum(*t))
7714             yield = string_catn(yield, US"\\", 1);
7715           yield = string_catn(yield, t, 1);
7716           }
7717         continue;
7718         }
7719
7720       /* RFC 2047 encodes, assuming headers_charset (default ISO 8859-1) as
7721       prescribed by the RFC, if there are characters that need to be encoded */
7722
7723       case EOP_RFC2047:
7724         {
7725         uschar buffer[2048];
7726         yield = string_cat(yield,
7727                             parse_quote_2047(sub, Ustrlen(sub), headers_charset,
7728                               buffer, sizeof(buffer), FALSE));
7729         continue;
7730         }
7731
7732       /* RFC 2047 decode */
7733
7734       case EOP_RFC2047D:
7735         {
7736         int len;
7737         uschar *error;
7738         uschar *decoded = rfc2047_decode(sub, check_rfc2047_length,
7739           headers_charset, '?', &len, &error);
7740         if (error)
7741           {
7742           expand_string_message = error;
7743           goto EXPAND_FAILED;
7744           }
7745         yield = string_catn(yield, decoded, len);
7746         continue;
7747         }
7748
7749       /* from_utf8 converts UTF-8 to 8859-1, turning non-existent chars into
7750       underscores */
7751
7752       case EOP_FROM_UTF8:
7753         {
7754         while (*sub != 0)
7755           {
7756           int c;
7757           uschar buff[4];
7758           GETUTF8INC(c, sub);
7759           if (c > 255) c = '_';
7760           buff[0] = c;
7761           yield = string_catn(yield, buff, 1);
7762           }
7763         continue;
7764         }
7765
7766           /* replace illegal UTF-8 sequences by replacement character  */
7767
7768       #define UTF8_REPLACEMENT_CHAR US"?"
7769
7770       case EOP_UTF8CLEAN:
7771         {
7772         int seq_len = 0, index = 0;
7773         int bytes_left = 0;
7774         long codepoint = -1;
7775         int complete;
7776         uschar seq_buff[4];                     /* accumulate utf-8 here */
7777
7778         while (*sub != 0)
7779           {
7780           complete = 0;
7781           uschar c = *sub++;
7782
7783           if (bytes_left)
7784             {
7785             if ((c & 0xc0) != 0x80)
7786                     /* wrong continuation byte; invalidate all bytes */
7787               complete = 1; /* error */
7788             else
7789               {
7790               codepoint = (codepoint << 6) | (c & 0x3f);
7791               seq_buff[index++] = c;
7792               if (--bytes_left == 0)            /* codepoint complete */
7793                 if(codepoint > 0x10FFFF)        /* is it too large? */
7794                   complete = -1;        /* error (RFC3629 limit) */
7795                 else
7796                   {             /* finished; output utf-8 sequence */
7797                   yield = string_catn(yield, seq_buff, seq_len);
7798                   index = 0;
7799                   }
7800               }
7801             }
7802           else  /* no bytes left: new sequence */
7803             {
7804             if((c & 0x80) == 0) /* 1-byte sequence, US-ASCII, keep it */
7805               {
7806               yield = string_catn(yield, &c, 1);
7807               continue;
7808               }
7809             if((c & 0xe0) == 0xc0)              /* 2-byte sequence */
7810               {
7811               if(c == 0xc0 || c == 0xc1)        /* 0xc0 and 0xc1 are illegal */
7812                 complete = -1;
7813               else
7814                 {
7815                   bytes_left = 1;
7816                   codepoint = c & 0x1f;
7817                 }
7818               }
7819             else if((c & 0xf0) == 0xe0)         /* 3-byte sequence */
7820               {
7821               bytes_left = 2;
7822               codepoint = c & 0x0f;
7823               }
7824             else if((c & 0xf8) == 0xf0)         /* 4-byte sequence */
7825               {
7826               bytes_left = 3;
7827               codepoint = c & 0x07;
7828               }
7829             else        /* invalid or too long (RFC3629 allows only 4 bytes) */
7830               complete = -1;
7831
7832             seq_buff[index++] = c;
7833             seq_len = bytes_left + 1;
7834             }           /* if(bytes_left) */
7835
7836           if (complete != 0)
7837             {
7838             bytes_left = index = 0;
7839             yield = string_catn(yield, UTF8_REPLACEMENT_CHAR, 1);
7840             }
7841           if ((complete == 1) && ((c & 0x80) == 0))
7842                         /* ASCII character follows incomplete sequence */
7843               yield = string_catn(yield, &c, 1);
7844           }
7845         /* If given a sequence truncated mid-character, we also want to report ?
7846         * Eg, ${length_1:フィル} is one byte, not one character, so we expect
7847         * ${utf8clean:${length_1:フィル}} to yield '?' */
7848         if (bytes_left != 0)
7849           {
7850           yield = string_catn(yield, UTF8_REPLACEMENT_CHAR, 1);
7851           }
7852         continue;
7853         }
7854
7855 #ifdef SUPPORT_I18N
7856       case EOP_UTF8_DOMAIN_TO_ALABEL:
7857         {
7858         uschar * error = NULL;
7859         uschar * s = string_domain_utf8_to_alabel(sub, &error);
7860         if (error)
7861           {
7862           expand_string_message = string_sprintf(
7863             "error converting utf8 (%s) to alabel: %s",
7864             string_printing(sub), error);
7865           goto EXPAND_FAILED;
7866           }
7867         yield = string_cat(yield, s);
7868         continue;
7869         }
7870
7871       case EOP_UTF8_DOMAIN_FROM_ALABEL:
7872         {
7873         uschar * error = NULL;
7874         uschar * s = string_domain_alabel_to_utf8(sub, &error);
7875         if (error)
7876           {
7877           expand_string_message = string_sprintf(
7878             "error converting alabel (%s) to utf8: %s",
7879             string_printing(sub), error);
7880           goto EXPAND_FAILED;
7881           }
7882         yield = string_cat(yield, s);
7883         continue;
7884         }
7885
7886       case EOP_UTF8_LOCALPART_TO_ALABEL:
7887         {
7888         uschar * error = NULL;
7889         uschar * s = string_localpart_utf8_to_alabel(sub, &error);
7890         if (error)
7891           {
7892           expand_string_message = string_sprintf(
7893             "error converting utf8 (%s) to alabel: %s",
7894             string_printing(sub), error);
7895           goto EXPAND_FAILED;
7896           }
7897         yield = string_cat(yield, s);
7898         DEBUG(D_expand) debug_printf_indent("yield: '%s'\n", yield->s);
7899         continue;
7900         }
7901
7902       case EOP_UTF8_LOCALPART_FROM_ALABEL:
7903         {
7904         uschar * error = NULL;
7905         uschar * s = string_localpart_alabel_to_utf8(sub, &error);
7906         if (error)
7907           {
7908           expand_string_message = string_sprintf(
7909             "error converting alabel (%s) to utf8: %s",
7910             string_printing(sub), error);
7911           goto EXPAND_FAILED;
7912           }
7913         yield = string_cat(yield, s);
7914         continue;
7915         }
7916 #endif  /* EXPERIMENTAL_INTERNATIONAL */
7917
7918       /* escape turns all non-printing characters into escape sequences. */
7919
7920       case EOP_ESCAPE:
7921         {
7922         const uschar * t = string_printing(sub);
7923         yield = string_cat(yield, t);
7924         continue;
7925         }
7926
7927       case EOP_ESCAPE8BIT:
7928         {
7929         uschar c;
7930
7931         for (const uschar * s = sub; (c = *s); s++)
7932           yield = c < 127 && c != '\\'
7933             ? string_catn(yield, s, 1)
7934             : string_fmt_append(yield, "\\%03o", c);
7935         continue;
7936         }
7937
7938       /* Handle numeric expression evaluation */
7939
7940       case EOP_EVAL:
7941       case EOP_EVAL10:
7942         {
7943         uschar *save_sub = sub;
7944         uschar *error = NULL;
7945         int_eximarith_t n = eval_expr(&sub, (c == EOP_EVAL10), &error, FALSE);
7946         if (error)
7947           {
7948           expand_string_message = string_sprintf("error in expression "
7949             "evaluation: %s (after processing \"%.*s\")", error,
7950             (int)(sub-save_sub), save_sub);
7951           goto EXPAND_FAILED;
7952           }
7953         yield = string_fmt_append(yield, PR_EXIM_ARITH, n);
7954         continue;
7955         }
7956
7957       /* Handle time period formatting */
7958
7959       case EOP_TIME_EVAL:
7960         {
7961         int n = readconf_readtime(sub, 0, FALSE);
7962         if (n < 0)
7963           {
7964           expand_string_message = string_sprintf("string \"%s\" is not an "
7965             "Exim time interval in \"%s\" operator", sub, name);
7966           goto EXPAND_FAILED;
7967           }
7968         yield = string_fmt_append(yield, "%d", n);
7969         continue;
7970         }
7971
7972       case EOP_TIME_INTERVAL:
7973         {
7974         int n;
7975         uschar *t = read_number(&n, sub);
7976         if (*t != 0) /* Not A Number*/
7977           {
7978           expand_string_message = string_sprintf("string \"%s\" is not a "
7979             "positive number in \"%s\" operator", sub, name);
7980           goto EXPAND_FAILED;
7981           }
7982         t = readconf_printtime(n);
7983         yield = string_cat(yield, t);
7984         continue;
7985         }
7986
7987       /* Convert string to base64 encoding */
7988
7989       case EOP_STR2B64:
7990       case EOP_BASE64:
7991         {
7992 #ifndef DISABLE_TLS
7993         uschar * s = vp && *(void **)vp->value
7994           ? tls_cert_der_b64(*(void **)vp->value)
7995           : b64encode(CUS sub, Ustrlen(sub));
7996 #else
7997         uschar * s = b64encode(CUS sub, Ustrlen(sub));
7998 #endif
7999         yield = string_cat(yield, s);
8000         continue;
8001         }
8002
8003       case EOP_BASE64D:
8004         {
8005         uschar * s;
8006         int len = b64decode(sub, &s);
8007         if (len < 0)
8008           {
8009           expand_string_message = string_sprintf("string \"%s\" is not "
8010             "well-formed for \"%s\" operator", sub, name);
8011           goto EXPAND_FAILED;
8012           }
8013         yield = string_cat(yield, s);
8014         continue;
8015         }
8016
8017       /* strlen returns the length of the string */
8018
8019       case EOP_STRLEN:
8020         yield = string_fmt_append(yield, "%d", Ustrlen(sub));
8021         continue;
8022
8023       /* length_n or l_n takes just the first n characters or the whole string,
8024       whichever is the shorter;
8025
8026       substr_m_n, and s_m_n take n characters from offset m; negative m take
8027       from the end; l_n is synonymous with s_0_n. If n is omitted in substr it
8028       takes the rest, either to the right or to the left.
8029
8030       hash_n or h_n makes a hash of length n from the string, yielding n
8031       characters from the set a-z; hash_n_m makes a hash of length n, but
8032       uses m characters from the set a-zA-Z0-9.
8033
8034       nhash_n returns a single number between 0 and n-1 (in text form), while
8035       nhash_n_m returns a div/mod hash as two numbers "a/b". The first lies
8036       between 0 and n-1 and the second between 0 and m-1. */
8037
8038       case EOP_LENGTH:
8039       case EOP_L:
8040       case EOP_SUBSTR:
8041       case EOP_S:
8042       case EOP_HASH:
8043       case EOP_H:
8044       case EOP_NHASH:
8045       case EOP_NH:
8046         {
8047         int sign = 1;
8048         int value1 = 0;
8049         int value2 = -1;
8050         int *pn;
8051         int len;
8052         uschar *ret;
8053
8054         if (!arg)
8055           {
8056           expand_string_message = string_sprintf("missing values after %s",
8057             name);
8058           goto EXPAND_FAILED;
8059           }
8060
8061         /* "length" has only one argument, effectively being synonymous with
8062         substr_0_n. */
8063
8064         if (c == EOP_LENGTH || c == EOP_L)
8065           {
8066           pn = &value2;
8067           value2 = 0;
8068           }
8069
8070         /* The others have one or two arguments; for "substr" the first may be
8071         negative. The second being negative means "not supplied". */
8072
8073         else
8074           {
8075           pn = &value1;
8076           if (name[0] == 's' && *arg == '-') { sign = -1; arg++; }
8077           }
8078
8079         /* Read up to two numbers, separated by underscores */
8080
8081         ret = arg;
8082         while (*arg != 0)
8083           {
8084           if (arg != ret && *arg == '_' && pn == &value1)
8085             {
8086             pn = &value2;
8087             value2 = 0;
8088             if (arg[1] != 0) arg++;
8089             }
8090           else if (!isdigit(*arg))
8091             {
8092             expand_string_message =
8093               string_sprintf("non-digit after underscore in \"%s\"", name);
8094             goto EXPAND_FAILED;
8095             }
8096           else *pn = (*pn)*10 + *arg++ - '0';
8097           }
8098         value1 *= sign;
8099
8100         /* Perform the required operation */
8101
8102         ret = c == EOP_HASH || c == EOP_H
8103           ? compute_hash(sub, value1, value2, &len)
8104           : c == EOP_NHASH || c == EOP_NH
8105           ? compute_nhash(sub, value1, value2, &len)
8106           : extract_substr(sub, value1, value2, &len);
8107         if (!ret) goto EXPAND_FAILED;
8108
8109         yield = string_catn(yield, ret, len);
8110         continue;
8111         }
8112
8113       /* Stat a path */
8114
8115       case EOP_STAT:
8116         {
8117         uschar smode[12];
8118         uschar **modetable[3];
8119         mode_t mode;
8120         struct stat st;
8121
8122         if (expand_forbid & RDO_EXISTS)
8123           {
8124           expand_string_message = US"Use of the stat() expansion is not permitted";
8125           goto EXPAND_FAILED;
8126           }
8127
8128         if (stat(CS sub, &st) < 0)
8129           {
8130           expand_string_message = string_sprintf("stat(%s) failed: %s",
8131             sub, strerror(errno));
8132           goto EXPAND_FAILED;
8133           }
8134         mode = st.st_mode;
8135         switch (mode & S_IFMT)
8136           {
8137           case S_IFIFO: smode[0] = 'p'; break;
8138           case S_IFCHR: smode[0] = 'c'; break;
8139           case S_IFDIR: smode[0] = 'd'; break;
8140           case S_IFBLK: smode[0] = 'b'; break;
8141           case S_IFREG: smode[0] = '-'; break;
8142           default: smode[0] = '?'; break;
8143           }
8144
8145         modetable[0] = ((mode & 01000) == 0)? mtable_normal : mtable_sticky;
8146         modetable[1] = ((mode & 02000) == 0)? mtable_normal : mtable_setid;
8147         modetable[2] = ((mode & 04000) == 0)? mtable_normal : mtable_setid;
8148
8149         for (int i = 0; i < 3; i++)
8150           {
8151           memcpy(CS(smode + 7 - i*3), CS(modetable[i][mode & 7]), 3);
8152           mode >>= 3;
8153           }
8154
8155         smode[10] = 0;
8156         yield = string_fmt_append(yield,
8157           "mode=%04lo smode=%s inode=%ld device=%ld links=%ld "
8158           "uid=%ld gid=%ld size=" OFF_T_FMT " atime=%ld mtime=%ld ctime=%ld",
8159           (long)(st.st_mode & 077777), smode, (long)st.st_ino,
8160           (long)st.st_dev, (long)st.st_nlink, (long)st.st_uid,
8161           (long)st.st_gid, st.st_size, (long)st.st_atime,
8162           (long)st.st_mtime, (long)st.st_ctime);
8163         continue;
8164         }
8165
8166       /* vaguely random number less than N */
8167
8168       case EOP_RANDINT:
8169         {
8170         int_eximarith_t max = expanded_string_integer(sub, TRUE);
8171
8172         if (expand_string_message)
8173           goto EXPAND_FAILED;
8174         yield = string_fmt_append(yield, "%d", vaguely_random_number((int)max));
8175         continue;
8176         }
8177
8178       /* Reverse IP, including IPv6 to dotted-nibble */
8179
8180       case EOP_REVERSE_IP:
8181         {
8182         int family, maskptr;
8183         uschar reversed[128];
8184
8185         family = string_is_ip_address(sub, &maskptr);
8186         if (family == 0)
8187           {
8188           expand_string_message = string_sprintf(
8189               "reverse_ip() not given an IP address [%s]", sub);
8190           goto EXPAND_FAILED;
8191           }
8192         invert_address(reversed, sub);
8193         yield = string_cat(yield, reversed);
8194         continue;
8195         }
8196
8197       /* Unknown operator */
8198
8199       default:
8200         expand_string_message =
8201           string_sprintf("unknown expansion operator \"%s\"", name);
8202         goto EXPAND_FAILED;
8203       }
8204     }
8205
8206   /* Handle a plain name. If this is the first thing in the expansion, release
8207   the pre-allocated buffer. If the result data is known to be in a new buffer,
8208   newsize will be set to the size of that buffer, and we can just point at that
8209   store instead of copying. Many expansion strings contain just one reference,
8210   so this is a useful optimization, especially for humungous headers
8211   ($message_headers). */
8212                                                 /*{*/
8213   if (*s++ == '}')
8214     {
8215     int len;
8216     int newsize = 0;
8217     gstring * g = NULL;
8218
8219     if (!yield)
8220       g = store_get(sizeof(gstring), FALSE);
8221     else if (yield->ptr == 0)
8222       {
8223       if (resetok) reset_point = store_reset(reset_point);
8224       yield = NULL;
8225       reset_point = store_mark();
8226       g = store_get(sizeof(gstring), FALSE);    /* alloc _before_ calling find_variable() */
8227       }
8228     if (!(value = find_variable(name, FALSE, skipping, &newsize)))
8229       {
8230       expand_string_message =
8231         string_sprintf("unknown variable in \"${%s}\"", name);
8232       check_variable_error_message(name);
8233       goto EXPAND_FAILED;
8234       }
8235     len = Ustrlen(value);
8236     if (!yield && newsize)
8237       {
8238       yield = g;
8239       yield->size = newsize;
8240       yield->ptr = len;
8241       yield->s = value;
8242       }
8243     else
8244       yield = string_catn(yield, value, len);
8245     continue;
8246     }
8247
8248   /* Else there's something wrong */
8249
8250   expand_string_message =
8251     string_sprintf("\"${%s\" is not a known operator (or a } is missing "
8252     "in a variable reference)", name);
8253   goto EXPAND_FAILED;
8254   }
8255
8256 /* If we hit the end of the string when ket_ends is set, there is a missing
8257 terminating brace. */
8258
8259 if (ket_ends && *s == 0)
8260   {
8261   expand_string_message = malformed_header
8262     ? US"missing } at end of string - could be header name not terminated by colon"
8263     : US"missing } at end of string";
8264   goto EXPAND_FAILED;
8265   }
8266
8267 /* Expansion succeeded; yield may still be NULL here if nothing was actually
8268 added to the string. If so, set up an empty string. Add a terminating zero. If
8269 left != NULL, return a pointer to the terminator. */
8270
8271 if (!yield)
8272   yield = string_get(1);
8273 (void) string_from_gstring(yield);
8274 if (left) *left = s;
8275
8276 /* Any stacking store that was used above the final string is no longer needed.
8277 In many cases the final string will be the first one that was got and so there
8278 will be optimal store usage. */
8279
8280 if (resetok) gstring_release_unused(yield);
8281 else if (resetok_p) *resetok_p = FALSE;
8282
8283 DEBUG(D_expand)
8284   {
8285   BOOL tainted = is_tainted(yield->s);
8286   DEBUG(D_noutf8)
8287     {
8288     debug_printf_indent("|--expanding: %.*s\n", (int)(s - string), string);
8289     debug_printf_indent("%sresult: %s\n",
8290       skipping ? "|-----" : "\\_____", yield->s);
8291     if (tainted)
8292       debug_printf_indent("%s     \\__(tainted)\n",
8293         skipping ? "|     " : "      ");
8294     if (skipping)
8295       debug_printf_indent("\\___skipping: result is not used\n");
8296     }
8297   else
8298     {
8299     debug_printf_indent(UTF8_VERT_RIGHT UTF8_HORIZ UTF8_HORIZ
8300       "expanding: %.*s\n",
8301       (int)(s - string), string);
8302     debug_printf_indent("%s" UTF8_HORIZ UTF8_HORIZ UTF8_HORIZ UTF8_HORIZ UTF8_HORIZ
8303       "result: %s\n",
8304       skipping ? UTF8_VERT_RIGHT : UTF8_UP_RIGHT,
8305       yield->s);
8306     if (tainted)
8307       debug_printf_indent("%s(tainted)\n",
8308         skipping
8309         ? UTF8_VERT "             " : "           " UTF8_UP_RIGHT UTF8_HORIZ UTF8_HORIZ);
8310     if (skipping)
8311       debug_printf_indent(UTF8_UP_RIGHT UTF8_HORIZ UTF8_HORIZ UTF8_HORIZ
8312         "skipping: result is not used\n");
8313     }
8314   }
8315 expand_level--;
8316 return yield->s;
8317
8318 /* This is the failure exit: easiest to program with a goto. We still need
8319 to update the pointer to the terminator, for cases of nested calls with "fail".
8320 */
8321
8322 EXPAND_FAILED_CURLY:
8323 if (malformed_header)
8324   expand_string_message =
8325     US"missing or misplaced { or } - could be header name not terminated by colon";
8326
8327 else if (!expand_string_message || !*expand_string_message)
8328   expand_string_message = US"missing or misplaced { or }";
8329
8330 /* At one point, Exim reset the store to yield (if yield was not NULL), but
8331 that is a bad idea, because expand_string_message is in dynamic store. */
8332
8333 EXPAND_FAILED:
8334 if (left) *left = s;
8335 DEBUG(D_expand)
8336   DEBUG(D_noutf8)
8337     {
8338     debug_printf_indent("|failed to expand: %s\n", string);
8339     debug_printf_indent("%serror message: %s\n",
8340       f.expand_string_forcedfail ? "|---" : "\\___", expand_string_message);
8341     if (f.expand_string_forcedfail)
8342       debug_printf_indent("\\failure was forced\n");
8343     }
8344   else
8345     {
8346     debug_printf_indent(UTF8_VERT_RIGHT "failed to expand: %s\n",
8347       string);
8348     debug_printf_indent("%s" UTF8_HORIZ UTF8_HORIZ UTF8_HORIZ
8349       "error message: %s\n",
8350       f.expand_string_forcedfail ? UTF8_VERT_RIGHT : UTF8_UP_RIGHT,
8351       expand_string_message);
8352     if (f.expand_string_forcedfail)
8353       debug_printf_indent(UTF8_UP_RIGHT "failure was forced\n");
8354     }
8355 if (resetok_p && !resetok) *resetok_p = FALSE;
8356 expand_level--;
8357 return NULL;
8358 }
8359
8360
8361 /* This is the external function call. Do a quick check for any expansion
8362 metacharacters, and if there are none, just return the input string.
8363
8364 Argument: the string to be expanded
8365 Returns:  the expanded string, or NULL if expansion failed; if failure was
8366           due to a lookup deferring, search_find_defer will be TRUE
8367 */
8368
8369 const uschar *
8370 expand_cstring(const uschar * string)
8371 {
8372 if (Ustrpbrk(string, "$\\") != NULL)
8373   {
8374   int old_pool = store_pool;
8375   uschar * s;
8376
8377   f.search_find_defer = FALSE;
8378   malformed_header = FALSE;
8379   store_pool = POOL_MAIN;
8380     s = expand_string_internal(string, FALSE, NULL, FALSE, TRUE, NULL);
8381   store_pool = old_pool;
8382   return s;
8383   }
8384 return string;
8385 }
8386
8387
8388 uschar *
8389 expand_string(uschar * string)
8390 {
8391 return US expand_cstring(CUS string);
8392 }
8393
8394
8395
8396
8397
8398 /*************************************************
8399 *              Expand and copy                   *
8400 *************************************************/
8401
8402 /* Now and again we want to expand a string and be sure that the result is in a
8403 new bit of store. This function does that.
8404 Since we know it has been copied, the de-const cast is safe.
8405
8406 Argument: the string to be expanded
8407 Returns:  the expanded string, always in a new bit of store, or NULL
8408 */
8409
8410 uschar *
8411 expand_string_copy(const uschar *string)
8412 {
8413 const uschar *yield = expand_cstring(string);
8414 if (yield == string) yield = string_copy(string);
8415 return US yield;
8416 }
8417
8418
8419
8420 /*************************************************
8421 *        Expand and interpret as an integer      *
8422 *************************************************/
8423
8424 /* Expand a string, and convert the result into an integer.
8425
8426 Arguments:
8427   string  the string to be expanded
8428   isplus  TRUE if a non-negative number is expected
8429
8430 Returns:  the integer value, or
8431           -1 for an expansion error               ) in both cases, message in
8432           -2 for an integer interpretation error  ) expand_string_message
8433           expand_string_message is set NULL for an OK integer
8434 */
8435
8436 int_eximarith_t
8437 expand_string_integer(uschar *string, BOOL isplus)
8438 {
8439 return expanded_string_integer(expand_string(string), isplus);
8440 }
8441
8442
8443 /*************************************************
8444  *         Interpret string as an integer        *
8445  *************************************************/
8446
8447 /* Convert a string (that has already been expanded) into an integer.
8448
8449 This function is used inside the expansion code.
8450
8451 Arguments:
8452   s       the string to be expanded
8453   isplus  TRUE if a non-negative number is expected
8454
8455 Returns:  the integer value, or
8456           -1 if string is NULL (which implies an expansion error)
8457           -2 for an integer interpretation error
8458           expand_string_message is set NULL for an OK integer
8459 */
8460
8461 static int_eximarith_t
8462 expanded_string_integer(const uschar *s, BOOL isplus)
8463 {
8464 int_eximarith_t value;
8465 uschar *msg = US"invalid integer \"%s\"";
8466 uschar *endptr;
8467
8468 /* If expansion failed, expand_string_message will be set. */
8469
8470 if (!s) return -1;
8471
8472 /* On an overflow, strtol() returns LONG_MAX or LONG_MIN, and sets errno
8473 to ERANGE. When there isn't an overflow, errno is not changed, at least on some
8474 systems, so we set it zero ourselves. */
8475
8476 errno = 0;
8477 expand_string_message = NULL;               /* Indicates no error */
8478
8479 /* Before Exim 4.64, strings consisting entirely of whitespace compared
8480 equal to 0.  Unfortunately, people actually relied upon that, so preserve
8481 the behaviour explicitly.  Stripping leading whitespace is a harmless
8482 noop change since strtol skips it anyway (provided that there is a number
8483 to find at all). */
8484 if (isspace(*s))
8485   {
8486   while (isspace(*s)) ++s;
8487   if (*s == '\0')
8488     {
8489       DEBUG(D_expand)
8490        debug_printf_indent("treating blank string as number 0\n");
8491       return 0;
8492     }
8493   }
8494
8495 value = strtoll(CS s, CSS &endptr, 10);
8496
8497 if (endptr == s)
8498   {
8499   msg = US"integer expected but \"%s\" found";
8500   }
8501 else if (value < 0 && isplus)
8502   {
8503   msg = US"non-negative integer expected but \"%s\" found";
8504   }
8505 else
8506   {
8507   switch (tolower(*endptr))
8508     {
8509     default:
8510       break;
8511     case 'k':
8512       if (value > EXIM_ARITH_MAX/1024 || value < EXIM_ARITH_MIN/1024) errno = ERANGE;
8513       else value *= 1024;
8514       endptr++;
8515       break;
8516     case 'm':
8517       if (value > EXIM_ARITH_MAX/(1024*1024) || value < EXIM_ARITH_MIN/(1024*1024)) errno = ERANGE;
8518       else value *= 1024*1024;
8519       endptr++;
8520       break;
8521     case 'g':
8522       if (value > EXIM_ARITH_MAX/(1024*1024*1024) || value < EXIM_ARITH_MIN/(1024*1024*1024)) errno = ERANGE;
8523       else value *= 1024*1024*1024;
8524       endptr++;
8525       break;
8526     }
8527   if (errno == ERANGE)
8528     msg = US"absolute value of integer \"%s\" is too large (overflow)";
8529   else
8530     {
8531     while (isspace(*endptr)) endptr++;
8532     if (*endptr == 0) return value;
8533     }
8534   }
8535
8536 expand_string_message = string_sprintf(CS msg, s);
8537 return -2;
8538 }
8539
8540
8541 /* These values are usually fixed boolean values, but they are permitted to be
8542 expanded strings.
8543
8544 Arguments:
8545   addr       address being routed
8546   mtype      the module type
8547   mname      the module name
8548   dbg_opt    debug selectors
8549   oname      the option name
8550   bvalue     the router's boolean value
8551   svalue     the router's string value
8552   rvalue     where to put the returned value
8553
8554 Returns:     OK     value placed in rvalue
8555              DEFER  expansion failed
8556 */
8557
8558 int
8559 exp_bool(address_item *addr,
8560   uschar *mtype, uschar *mname, unsigned dbg_opt,
8561   uschar *oname, BOOL bvalue,
8562   uschar *svalue, BOOL *rvalue)
8563 {
8564 uschar *expanded;
8565 if (!svalue) { *rvalue = bvalue; return OK; }
8566
8567 if (!(expanded = expand_string(svalue)))
8568   {
8569   if (f.expand_string_forcedfail)
8570     {
8571     DEBUG(dbg_opt) debug_printf("expansion of \"%s\" forced failure\n", oname);
8572     *rvalue = bvalue;
8573     return OK;
8574     }
8575   addr->message = string_sprintf("failed to expand \"%s\" in %s %s: %s",
8576       oname, mname, mtype, expand_string_message);
8577   DEBUG(dbg_opt) debug_printf("%s\n", addr->message);
8578   return DEFER;
8579   }
8580
8581 DEBUG(dbg_opt) debug_printf("expansion of \"%s\" yields \"%s\"\n", oname,
8582   expanded);
8583
8584 if (strcmpic(expanded, US"true") == 0 || strcmpic(expanded, US"yes") == 0)
8585   *rvalue = TRUE;
8586 else if (strcmpic(expanded, US"false") == 0 || strcmpic(expanded, US"no") == 0)
8587   *rvalue = FALSE;
8588 else
8589   {
8590   addr->message = string_sprintf("\"%s\" is not a valid value for the "
8591     "\"%s\" option in the %s %s", expanded, oname, mname, mtype);
8592   return DEFER;
8593   }
8594
8595 return OK;
8596 }
8597
8598
8599
8600 /* Avoid potentially exposing a password in a string about to be logged */
8601
8602 uschar *
8603 expand_hide_passwords(uschar * s)
8604 {
8605 return (  (  Ustrstr(s, "failed to expand") != NULL
8606           || Ustrstr(s, "expansion of ")    != NULL
8607           )
8608        && (  Ustrstr(s, "mysql")   != NULL
8609           || Ustrstr(s, "pgsql")   != NULL
8610           || Ustrstr(s, "redis")   != NULL
8611           || Ustrstr(s, "sqlite")  != NULL
8612           || Ustrstr(s, "ldap:")   != NULL
8613           || Ustrstr(s, "ldaps:")  != NULL
8614           || Ustrstr(s, "ldapi:")  != NULL
8615           || Ustrstr(s, "ldapdn:") != NULL
8616           || Ustrstr(s, "ldapm:")  != NULL
8617        )  )
8618   ? US"Temporary internal error" : s;
8619 }
8620
8621
8622 /* Read given named file into big_buffer.  Use for keying material etc.
8623 The content will have an ascii NUL appended.
8624
8625 Arguments:
8626  filename       as it says
8627
8628 Return:  pointer to buffer, or NULL on error.
8629 */
8630
8631 uschar *
8632 expand_file_big_buffer(const uschar * filename)
8633 {
8634 int fd, off = 0, len;
8635
8636 if ((fd = exim_open2(CS filename, O_RDONLY)) < 0)
8637   {
8638   log_write(0, LOG_MAIN | LOG_PANIC, "unable to open file for reading: %s",
8639              filename);
8640   return NULL;
8641   }
8642
8643 do
8644   {
8645   if ((len = read(fd, big_buffer + off, big_buffer_size - 2 - off)) < 0)
8646     {
8647     (void) close(fd);
8648     log_write(0, LOG_MAIN|LOG_PANIC, "unable to read file: %s", filename);
8649     return NULL;
8650     }
8651   off += len;
8652   }
8653 while (len > 0);
8654
8655 (void) close(fd);
8656 big_buffer[off] = '\0';
8657 return big_buffer;
8658 }
8659
8660
8661
8662 /*************************************************
8663 * Error-checking for testsuite                   *
8664 *************************************************/
8665 typedef struct {
8666   uschar *      region_start;
8667   uschar *      region_end;
8668   const uschar *var_name;
8669   const uschar *var_data;
8670 } err_ctx;
8671
8672 static void
8673 assert_variable_notin(uschar * var_name, uschar * var_data, void * ctx)
8674 {
8675 err_ctx * e = ctx;
8676 if (var_data >= e->region_start  &&  var_data < e->region_end)
8677   {
8678   e->var_name = CUS var_name;
8679   e->var_data = CUS var_data;
8680   }
8681 }
8682
8683 void
8684 assert_no_variables(void * ptr, int len, const char * filename, int linenumber)
8685 {
8686 err_ctx e = { .region_start = ptr, .region_end = US ptr + len,
8687               .var_name = NULL, .var_data = NULL };
8688
8689 /* check acl_ variables */
8690 tree_walk(acl_var_c, assert_variable_notin, &e);
8691 tree_walk(acl_var_m, assert_variable_notin, &e);
8692
8693 /* check auth<n> variables */
8694 for (int i = 0; i < AUTH_VARS; i++) if (auth_vars[i])
8695   assert_variable_notin(US"auth<n>", auth_vars[i], &e);
8696
8697 /* check regex<n> variables */
8698 for (int i = 0; i < REGEX_VARS; i++) if (regex_vars[i])
8699   assert_variable_notin(US"regex<n>", regex_vars[i], &e);
8700
8701 /* check known-name variables */
8702 for (var_entry * v = var_table; v < var_table + var_table_size; v++)
8703   if (v->type == vtype_stringptr)
8704     assert_variable_notin(US v->name, *(USS v->value), &e);
8705
8706 /* check dns and address trees */
8707 tree_walk(tree_dns_fails,     assert_variable_notin, &e);
8708 tree_walk(tree_duplicates,    assert_variable_notin, &e);
8709 tree_walk(tree_nonrecipients, assert_variable_notin, &e);
8710 tree_walk(tree_unusable,      assert_variable_notin, &e);
8711
8712 if (e.var_name)
8713   log_write(0, LOG_MAIN|LOG_PANIC_DIE,
8714     "live variable '%s' destroyed by reset_store at %s:%d\n- value '%.64s'",
8715     e.var_name, filename, linenumber, e.var_data);
8716 }
8717
8718
8719
8720 /*************************************************
8721 **************************************************
8722 *             Stand-alone test program           *
8723 **************************************************
8724 *************************************************/
8725
8726 #ifdef STAND_ALONE
8727
8728
8729 BOOL
8730 regex_match_and_setup(const pcre *re, uschar *subject, int options, int setup)
8731 {
8732 int ovector[3*(EXPAND_MAXN+1)];
8733 int n = pcre_exec(re, NULL, subject, Ustrlen(subject), 0, PCRE_EOPT|options,
8734   ovector, nelem(ovector));
8735 BOOL yield = n >= 0;
8736 if (n == 0) n = EXPAND_MAXN + 1;
8737 if (yield)
8738   {
8739   expand_nmax = setup < 0 ? 0 : setup + 1;
8740   for (int nn = setup < 0 ? 0 : 2; nn < n*2; nn += 2)
8741     {
8742     expand_nstring[expand_nmax] = subject + ovector[nn];
8743     expand_nlength[expand_nmax++] = ovector[nn+1] - ovector[nn];
8744     }
8745   expand_nmax--;
8746   }
8747 return yield;
8748 }
8749
8750
8751 int main(int argc, uschar **argv)
8752 {
8753 uschar buffer[1024];
8754
8755 debug_selector = D_v;
8756 debug_file = stderr;
8757 debug_fd = fileno(debug_file);
8758 big_buffer = malloc(big_buffer_size);
8759
8760 for (int i = 1; i < argc; i++)
8761   {
8762   if (argv[i][0] == '+')
8763     {
8764     debug_trace_memory = 2;
8765     argv[i]++;
8766     }
8767   if (isdigit(argv[i][0]))
8768     debug_selector = Ustrtol(argv[i], NULL, 0);
8769   else
8770     if (Ustrspn(argv[i], "abcdefghijklmnopqrtsuvwxyz0123456789-.:/") ==
8771         Ustrlen(argv[i]))
8772       {
8773 #ifdef LOOKUP_LDAP
8774       eldap_default_servers = argv[i];
8775 #endif
8776 #ifdef LOOKUP_MYSQL
8777       mysql_servers = argv[i];
8778 #endif
8779 #ifdef LOOKUP_PGSQL
8780       pgsql_servers = argv[i];
8781 #endif
8782 #ifdef LOOKUP_REDIS
8783       redis_servers = argv[i];
8784 #endif
8785       }
8786 #ifdef EXIM_PERL
8787   else opt_perl_startup = argv[i];
8788 #endif
8789   }
8790
8791 printf("Testing string expansion: debug_level = %d\n\n", debug_level);
8792
8793 expand_nstring[1] = US"string 1....";
8794 expand_nlength[1] = 8;
8795 expand_nmax = 1;
8796
8797 #ifdef EXIM_PERL
8798 if (opt_perl_startup != NULL)
8799   {
8800   uschar *errstr;
8801   printf("Starting Perl interpreter\n");
8802   errstr = init_perl(opt_perl_startup);
8803   if (errstr != NULL)
8804     {
8805     printf("** error in perl_startup code: %s\n", errstr);
8806     return EXIT_FAILURE;
8807     }
8808   }
8809 #endif /* EXIM_PERL */
8810
8811 /* Thie deliberately regards the input as untainted, so that it can be
8812 expanded; only reasonable since this is a test for string-expansions. */
8813
8814 while (fgets(buffer, sizeof(buffer), stdin) != NULL)
8815   {
8816   rmark reset_point = store_mark();
8817   uschar *yield = expand_string(buffer);
8818   if (yield)
8819     printf("%s\n", yield);
8820   else
8821     {
8822     if (f.search_find_defer) printf("search_find deferred\n");
8823     printf("Failed: %s\n", expand_string_message);
8824     if (f.expand_string_forcedfail) printf("Forced failure\n");
8825     printf("\n");
8826     }
8827   store_reset(reset_point);
8828   }
8829
8830 search_tidyup();
8831
8832 return 0;
8833 }
8834
8835 #endif
8836
8837 /* vi: aw ai sw=2
8838 */
8839 /* End of expand.c */