src/src/expand.c

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