src/src/expand.c

   1 /*************************************************
   2 *     Exim - an Internet mail transport agent    *
   3 *************************************************/
   4
   5 /* Copyright (c) University of Cambridge 1995 - 2016 */
   6 /* See the file NOTICE for conditions of use and distribution. */
   7
   8
   9 /* Functions for handling string expansion. */
  10
  11
  12 #include "exim.h"
  13
  14 /* Recursively called function */
  15
  16 static uschar *expand_string_internal(const uschar *, BOOL, const uschar **, BOOL, BOOL, BOOL *);
  17 static int_eximarith_t expanded_string_integer(const uschar *, BOOL);
  18
  19 #ifdef STAND_ALONE
  20 #ifndef SUPPORT_CRYPTEQ
  21 #define SUPPORT_CRYPTEQ
  22 #endif
  23 #endif
  24
  25 #ifdef LOOKUP_LDAP
  26 #include "lookups/ldap.h"
  27 #endif
  28
  29 #ifdef SUPPORT_CRYPTEQ
  30 #ifdef CRYPT_H
  31 #include <crypt.h>
  32 #endif
  33 #ifndef HAVE_CRYPT16
  34 extern char* crypt16(char*, char*);
  35 #endif
  36 #endif
  37
  38 /* The handling of crypt16() is a mess. I will record below the analysis of the
  39 mess that was sent to me. We decided, however, to make changing this very low
  40 priority, because in practice people are moving away from the crypt()
  41 algorithms nowadays, so it doesn't seem worth it.
  42
  43 <quote>
  44 There is an algorithm named "crypt16" in Ultrix and Tru64.  It crypts
  45 the first 8 characters of the password using a 20-round version of crypt
  46 (standard crypt does 25 rounds).  It then crypts the next 8 characters,
  47 or an empty block if the password is less than 9 characters, using a
  48 20-round version of crypt and the same salt as was used for the first
  49 block.  Charaters after the first 16 are ignored.  It always generates
  50 a 16-byte hash, which is expressed together with the salt as a string
  51 of 24 base 64 digits.  Here are some links to peruse:
  52
  53         http://cvs.pld.org.pl/pam/pamcrypt/crypt16.c?rev=1.2
  54         http://seclists.org/bugtraq/1999/Mar/0076.html
  55
  56 There's a different algorithm named "bigcrypt" in HP-UX, Digital Unix,
  57 and OSF/1.  This is the same as the standard crypt if given a password
  58 of 8 characters or less.  If given more, it first does the same as crypt
  59 using the first 8 characters, then crypts the next 8 (the 9th to 16th)
  60 using as salt the first two base 64 digits from the first hash block.
  61 If the password is more than 16 characters then it crypts the 17th to 24th
  62 characters using as salt the first two base 64 digits from the second hash
  63 block.  And so on: I've seen references to it cutting off the password at
  64 40 characters (5 blocks), 80 (10 blocks), or 128 (16 blocks).  Some links:
  65
  66         http://cvs.pld.org.pl/pam/pamcrypt/bigcrypt.c?rev=1.2
  67         http://seclists.org/bugtraq/1999/Mar/0109.html
  68         http://h30097.www3.hp.com/docs/base_doc/DOCUMENTATION/HTML/AA-Q0R2D-
  69              TET1_html/sec.c222.html#no_id_208
  70
  71 Exim has something it calls "crypt16".  It will either use a native
  72 crypt16 or its own implementation.  A native crypt16 will presumably
  73 be the one that I called "crypt16" above.  The internal "crypt16"
  74 function, however, is a two-block-maximum implementation of what I called
  75 "bigcrypt".  The documentation matches the internal code.
  76
  77 I suspect that whoever did the "crypt16" stuff for Exim didn't realise
  78 that crypt16 and bigcrypt were different things.
  79
  80 Exim uses the LDAP-style scheme identifier "{crypt16}" to refer
  81 to whatever it is using under that name.  This unfortunately sets a
  82 precedent for using "{crypt16}" to identify two incompatible algorithms
  83 whose output can't be distinguished.  With "{crypt16}" thus rendered
  84 ambiguous, I suggest you deprecate it and invent two new identifiers
  85 for the two algorithms.
  86
  87 Both crypt16 and bigcrypt are very poor algorithms, btw.  Hashing parts
  88 of the password separately means they can be cracked separately, so
  89 the double-length hash only doubles the cracking effort instead of
  90 squaring it.  I recommend salted SHA-1 ({SSHA}), or the Blowfish-based
  91 bcrypt ({CRYPT}$2a$).
  92 </quote>
  93 */
  94
  95
  96
  97 /*************************************************
  98 *            Local statics and tables            *
  99 *************************************************/
 100
 101 /* Table of item names, and corresponding switch numbers. The names must be in
 102 alphabetical order. */
 103
 104 static uschar *item_table[] = {
 105   US"acl",
 106   US"certextract",
 107   US"dlfunc",
 108   US"env",
 109   US"extract",
 110   US"filter",
 111   US"hash",
 112   US"hmac",
 113   US"if",
 114 #ifdef SUPPORT_I18N
 115   US"imapfolder",
 116 #endif
 117   US"length",
 118   US"listextract",
 119   US"lookup",
 120   US"map",
 121   US"nhash",
 122   US"perl",
 123   US"prvs",
 124   US"prvscheck",
 125   US"readfile",
 126   US"readsocket",
 127   US"reduce",
 128   US"run",
 129   US"sg",
 130   US"sort",
 131   US"substr",
 132   US"tr" };
 133
 134 enum {
 135   EITEM_ACL,
 136   EITEM_CERTEXTRACT,
 137   EITEM_DLFUNC,
 138   EITEM_ENV,
 139   EITEM_EXTRACT,
 140   EITEM_FILTER,
 141   EITEM_HASH,
 142   EITEM_HMAC,
 143   EITEM_IF,
 144 #ifdef SUPPORT_I18N
 145   EITEM_IMAPFOLDER,
 146 #endif
 147   EITEM_LENGTH,
 148   EITEM_LISTEXTRACT,
 149   EITEM_LOOKUP,
 150   EITEM_MAP,
 151   EITEM_NHASH,
 152   EITEM_PERL,
 153   EITEM_PRVS,
 154   EITEM_PRVSCHECK,
 155   EITEM_READFILE,
 156   EITEM_READSOCK,
 157   EITEM_REDUCE,
 158   EITEM_RUN,
 159   EITEM_SG,
 160   EITEM_SORT,
 161   EITEM_SUBSTR,
 162   EITEM_TR };
 163
 164 /* Tables of operator names, and corresponding switch numbers. The names must be
 165 in alphabetical order. There are two tables, because underscore is used in some
 166 cases to introduce arguments, whereas for other it is part of the name. This is
 167 an historical mis-design. */
 168
 169 static uschar *op_table_underscore[] = {
 170   US"from_utf8",
 171   US"local_part",
 172   US"quote_local_part",
 173   US"reverse_ip",
 174   US"time_eval",
 175   US"time_interval"
 176 #ifdef SUPPORT_I18N
 177  ,US"utf8_domain_from_alabel",
 178   US"utf8_domain_to_alabel",
 179   US"utf8_localpart_from_alabel",
 180   US"utf8_localpart_to_alabel"
 181 #endif
 182   };
 183
 184 enum {
 185   EOP_FROM_UTF8,
 186   EOP_LOCAL_PART,
 187   EOP_QUOTE_LOCAL_PART,
 188   EOP_REVERSE_IP,
 189   EOP_TIME_EVAL,
 190   EOP_TIME_INTERVAL
 191 #ifdef SUPPORT_I18N
 192  ,EOP_UTF8_DOMAIN_FROM_ALABEL,
 193   EOP_UTF8_DOMAIN_TO_ALABEL,
 194   EOP_UTF8_LOCALPART_FROM_ALABEL,
 195   EOP_UTF8_LOCALPART_TO_ALABEL
 196 #endif
 197   };
 198
 199 static uschar *op_table_main[] = {
 200   US"address",
 201   US"addresses",
 202   US"base62",
 203   US"base62d",
 204   US"base64",
 205   US"base64d",
 206   US"domain",
 207   US"escape",
 208   US"eval",
 209   US"eval10",
 210   US"expand",
 211   US"h",
 212   US"hash",
 213   US"hex2b64",
 214   US"hexquote",
 215   US"ipv6denorm",
 216   US"ipv6norm",
 217   US"l",
 218   US"lc",
 219   US"length",
 220   US"listcount",
 221   US"listnamed",
 222   US"mask",
 223   US"md5",
 224   US"nh",
 225   US"nhash",
 226   US"quote",
 227   US"randint",
 228   US"rfc2047",
 229   US"rfc2047d",
 230   US"rxquote",
 231   US"s",
 232   US"sha1",
 233   US"sha256",
 234   US"stat",
 235   US"str2b64",
 236   US"strlen",
 237   US"substr",
 238   US"uc",
 239   US"utf8clean" };
 240
 241 enum {
 242   EOP_ADDRESS =  nelem(op_table_underscore),
 243   EOP_ADDRESSES,
 244   EOP_BASE62,
 245   EOP_BASE62D,
 246   EOP_BASE64,
 247   EOP_BASE64D,
 248   EOP_DOMAIN,
 249   EOP_ESCAPE,
 250   EOP_EVAL,
 251   EOP_EVAL10,
 252   EOP_EXPAND,
 253   EOP_H,
 254   EOP_HASH,
 255   EOP_HEX2B64,
 256   EOP_HEXQUOTE,
 257   EOP_IPV6DENORM,
 258   EOP_IPV6NORM,
 259   EOP_L,
 260   EOP_LC,
 261   EOP_LENGTH,
 262   EOP_LISTCOUNT,
 263   EOP_LISTNAMED,
 264   EOP_MASK,
 265   EOP_MD5,
 266   EOP_NH,
 267   EOP_NHASH,
 268   EOP_QUOTE,
 269   EOP_RANDINT,
 270   EOP_RFC2047,
 271   EOP_RFC2047D,
 272   EOP_RXQUOTE,
 273   EOP_S,
 274   EOP_SHA1,
 275   EOP_SHA256,
 276   EOP_STAT,
 277   EOP_STR2B64,
 278   EOP_STRLEN,
 279   EOP_SUBSTR,
 280   EOP_UC,
 281   EOP_UTF8CLEAN };
 282
 283
 284 /* Table of condition names, and corresponding switch numbers. The names must
 285 be in alphabetical order. */
 286
 287 static uschar *cond_table[] = {
 288   US"<",
 289   US"<=",
 290   US"=",
 291   US"==",     /* Backward compatibility */
 292   US">",
 293   US">=",
 294   US"acl",
 295   US"and",
 296   US"bool",
 297   US"bool_lax",
 298   US"crypteq",
 299   US"def",
 300   US"eq",
 301   US"eqi",
 302   US"exists",
 303   US"first_delivery",
 304   US"forall",
 305   US"forany",
 306   US"ge",
 307   US"gei",
 308   US"gt",
 309   US"gti",
 310   US"inlist",
 311   US"inlisti",
 312   US"isip",
 313   US"isip4",
 314   US"isip6",
 315   US"ldapauth",
 316   US"le",
 317   US"lei",
 318   US"lt",
 319   US"lti",
 320   US"match",
 321   US"match_address",
 322   US"match_domain",
 323   US"match_ip",
 324   US"match_local_part",
 325   US"or",
 326   US"pam",
 327   US"pwcheck",
 328   US"queue_running",
 329   US"radius",
 330   US"saslauthd"
 331 };
 332
 333 enum {
 334   ECOND_NUM_L,
 335   ECOND_NUM_LE,
 336   ECOND_NUM_E,
 337   ECOND_NUM_EE,
 338   ECOND_NUM_G,
 339   ECOND_NUM_GE,
 340   ECOND_ACL,
 341   ECOND_AND,
 342   ECOND_BOOL,
 343   ECOND_BOOL_LAX,
 344   ECOND_CRYPTEQ,
 345   ECOND_DEF,
 346   ECOND_STR_EQ,
 347   ECOND_STR_EQI,
 348   ECOND_EXISTS,
 349   ECOND_FIRST_DELIVERY,
 350   ECOND_FORALL,
 351   ECOND_FORANY,
 352   ECOND_STR_GE,
 353   ECOND_STR_GEI,
 354   ECOND_STR_GT,
 355   ECOND_STR_GTI,
 356   ECOND_INLIST,
 357   ECOND_INLISTI,
 358   ECOND_ISIP,
 359   ECOND_ISIP4,
 360   ECOND_ISIP6,
 361   ECOND_LDAPAUTH,
 362   ECOND_STR_LE,
 363   ECOND_STR_LEI,
 364   ECOND_STR_LT,
 365   ECOND_STR_LTI,
 366   ECOND_MATCH,
 367   ECOND_MATCH_ADDRESS,
 368   ECOND_MATCH_DOMAIN,
 369   ECOND_MATCH_IP,
 370   ECOND_MATCH_LOCAL_PART,
 371   ECOND_OR,
 372   ECOND_PAM,
 373   ECOND_PWCHECK,
 374   ECOND_QUEUE_RUNNING,
 375   ECOND_RADIUS,
 376   ECOND_SASLAUTHD
 377 };
 378
 379
 380 /* Types of table entry */
 381
 382 enum vtypes {
 383   vtype_int,            /* value is address of int */
 384   vtype_filter_int,     /* ditto, but recognized only when filtering */
 385   vtype_ino,            /* value is address of ino_t (not always an int) */
 386   vtype_uid,            /* value is address of uid_t (not always an int) */
 387   vtype_gid,            /* value is address of gid_t (not always an int) */
 388   vtype_bool,           /* value is address of bool */
 389   vtype_stringptr,      /* value is address of pointer to string */
 390   vtype_msgbody,        /* as stringptr, but read when first required */
 391   vtype_msgbody_end,    /* ditto, the end of the message */
 392   vtype_msgheaders,     /* the message's headers, processed */
 393   vtype_msgheaders_raw, /* the message's headers, unprocessed */
 394   vtype_localpart,      /* extract local part from string */
 395   vtype_domain,         /* extract domain from string */
 396   vtype_string_func,    /* value is string returned by given function */
 397   vtype_todbsdin,       /* value not used; generate BSD inbox tod */
 398   vtype_tode,           /* value not used; generate tod in epoch format */
 399   vtype_todel,          /* value not used; generate tod in epoch/usec format */
 400   vtype_todf,           /* value not used; generate full tod */
 401   vtype_todl,           /* value not used; generate log tod */
 402   vtype_todlf,          /* value not used; generate log file datestamp tod */
 403   vtype_todzone,        /* value not used; generate time zone only */
 404   vtype_todzulu,        /* value not used; generate zulu tod */
 405   vtype_reply,          /* value not used; get reply from headers */
 406   vtype_pid,            /* value not used; result is pid */
 407   vtype_host_lookup,    /* value not used; get host name */
 408   vtype_load_avg,       /* value not used; result is int from os_getloadavg */
 409   vtype_pspace,         /* partition space; value is T/F for spool/log */
 410   vtype_pinodes,        /* partition inodes; value is T/F for spool/log */
 411   vtype_cert            /* SSL certificate */
 412   #ifndef DISABLE_DKIM
 413   ,vtype_dkim           /* Lookup of value in DKIM signature */
 414   #endif
 415 };
 416
 417 /* Type for main variable table */
 418
 419 typedef struct {
 420   const char *name;
 421   enum vtypes type;
 422   void       *value;
 423 } var_entry;
 424
 425 /* Type for entries pointing to address/length pairs. Not currently
 426 in use. */
 427
 428 typedef struct {
 429   uschar **address;
 430   int  *length;
 431 } alblock;
 432
 433 static uschar * fn_recipients(void);
 434
 435 /* This table must be kept in alphabetical order. */
 436
 437 static var_entry var_table[] = {
 438   /* WARNING: Do not invent variables whose names start acl_c or acl_m because
 439      they will be confused with user-creatable ACL variables. */
 440   { "acl_arg1",            vtype_stringptr,   &acl_arg[0] },
 441   { "acl_arg2",            vtype_stringptr,   &acl_arg[1] },
 442   { "acl_arg3",            vtype_stringptr,   &acl_arg[2] },
 443   { "acl_arg4",            vtype_stringptr,   &acl_arg[3] },
 444   { "acl_arg5",            vtype_stringptr,   &acl_arg[4] },
 445   { "acl_arg6",            vtype_stringptr,   &acl_arg[5] },
 446   { "acl_arg7",            vtype_stringptr,   &acl_arg[6] },
 447   { "acl_arg8",            vtype_stringptr,   &acl_arg[7] },
 448   { "acl_arg9",            vtype_stringptr,   &acl_arg[8] },
 449   { "acl_narg",            vtype_int,         &acl_narg },
 450   { "acl_verify_message",  vtype_stringptr,   &acl_verify_message },
 451   { "address_data",        vtype_stringptr,   &deliver_address_data },
 452   { "address_file",        vtype_stringptr,   &address_file },
 453   { "address_pipe",        vtype_stringptr,   &address_pipe },
 454   { "authenticated_fail_id",vtype_stringptr,  &authenticated_fail_id },
 455   { "authenticated_id",    vtype_stringptr,   &authenticated_id },
 456   { "authenticated_sender",vtype_stringptr,   &authenticated_sender },
 457   { "authentication_failed",vtype_int,        &authentication_failed },
 458 #ifdef WITH_CONTENT_SCAN
 459   { "av_failed",           vtype_int,         &av_failed },
 460 #endif
 461 #ifdef EXPERIMENTAL_BRIGHTMAIL
 462   { "bmi_alt_location",    vtype_stringptr,   &bmi_alt_location },
 463   { "bmi_base64_tracker_verdict", vtype_stringptr, &bmi_base64_tracker_verdict },
 464   { "bmi_base64_verdict",  vtype_stringptr,   &bmi_base64_verdict },
 465   { "bmi_deliver",         vtype_int,         &bmi_deliver },
 466 #endif
 467   { "body_linecount",      vtype_int,         &body_linecount },
 468   { "body_zerocount",      vtype_int,         &body_zerocount },
 469   { "bounce_recipient",    vtype_stringptr,   &bounce_recipient },
 470   { "bounce_return_size_limit", vtype_int,    &bounce_return_size_limit },
 471   { "caller_gid",          vtype_gid,         &real_gid },
 472   { "caller_uid",          vtype_uid,         &real_uid },
 473   { "callout_address",     vtype_stringptr,   &callout_address },
 474   { "compile_date",        vtype_stringptr,   &version_date },
 475   { "compile_number",      vtype_stringptr,   &version_cnumber },
 476   { "config_dir",          vtype_stringptr,   &config_main_directory },
 477   { "config_file",         vtype_stringptr,   &config_main_filename },
 478   { "csa_status",          vtype_stringptr,   &csa_status },
 479 #ifdef EXPERIMENTAL_DCC
 480   { "dcc_header",          vtype_stringptr,   &dcc_header },
 481   { "dcc_result",          vtype_stringptr,   &dcc_result },
 482 #endif
 483 #ifndef DISABLE_DKIM
 484   { "dkim_algo",           vtype_dkim,        (void *)DKIM_ALGO },
 485   { "dkim_bodylength",     vtype_dkim,        (void *)DKIM_BODYLENGTH },
 486   { "dkim_canon_body",     vtype_dkim,        (void *)DKIM_CANON_BODY },
 487   { "dkim_canon_headers",  vtype_dkim,        (void *)DKIM_CANON_HEADERS },
 488   { "dkim_copiedheaders",  vtype_dkim,        (void *)DKIM_COPIEDHEADERS },
 489   { "dkim_created",        vtype_dkim,        (void *)DKIM_CREATED },
 490   { "dkim_cur_signer",     vtype_stringptr,   &dkim_cur_signer },
 491   { "dkim_domain",         vtype_stringptr,   &dkim_signing_domain },
 492   { "dkim_expires",        vtype_dkim,        (void *)DKIM_EXPIRES },
 493   { "dkim_headernames",    vtype_dkim,        (void *)DKIM_HEADERNAMES },
 494   { "dkim_identity",       vtype_dkim,        (void *)DKIM_IDENTITY },
 495   { "dkim_key_granularity",vtype_dkim,        (void *)DKIM_KEY_GRANULARITY },
 496   { "dkim_key_length",     vtype_int,         &dkim_key_length },
 497   { "dkim_key_nosubdomains",vtype_dkim,       (void *)DKIM_NOSUBDOMAINS },
 498   { "dkim_key_notes",      vtype_dkim,        (void *)DKIM_KEY_NOTES },
 499   { "dkim_key_srvtype",    vtype_dkim,        (void *)DKIM_KEY_SRVTYPE },
 500   { "dkim_key_testing",    vtype_dkim,        (void *)DKIM_KEY_TESTING },
 501   { "dkim_selector",       vtype_stringptr,   &dkim_signing_selector },
 502   { "dkim_signers",        vtype_stringptr,   &dkim_signers },
 503   { "dkim_verify_reason",  vtype_dkim,        (void *)DKIM_VERIFY_REASON },
 504   { "dkim_verify_status",  vtype_dkim,        (void *)DKIM_VERIFY_STATUS},
 505 #endif
 506 #ifdef EXPERIMENTAL_DMARC
 507   { "dmarc_ar_header",     vtype_stringptr,   &dmarc_ar_header },
 508   { "dmarc_domain_policy", vtype_stringptr,   &dmarc_domain_policy },
 509   { "dmarc_status",        vtype_stringptr,   &dmarc_status },
 510   { "dmarc_status_text",   vtype_stringptr,   &dmarc_status_text },
 511   { "dmarc_used_domain",   vtype_stringptr,   &dmarc_used_domain },
 512 #endif
 513   { "dnslist_domain",      vtype_stringptr,   &dnslist_domain },
 514   { "dnslist_matched",     vtype_stringptr,   &dnslist_matched },
 515   { "dnslist_text",        vtype_stringptr,   &dnslist_text },
 516   { "dnslist_value",       vtype_stringptr,   &dnslist_value },
 517   { "domain",              vtype_stringptr,   &deliver_domain },
 518   { "domain_data",         vtype_stringptr,   &deliver_domain_data },
 519 #ifndef DISABLE_EVENT
 520   { "event_data",          vtype_stringptr,   &event_data },
 521
 522   /*XXX want to use generic vars for as many of these as possible*/
 523   { "event_defer_errno",   vtype_int,         &event_defer_errno },
 524
 525   { "event_name",          vtype_stringptr,   &event_name },
 526 #endif
 527   { "exim_gid",            vtype_gid,         &exim_gid },
 528   { "exim_path",           vtype_stringptr,   &exim_path },
 529   { "exim_uid",            vtype_uid,         &exim_uid },
 530   { "exim_version",        vtype_stringptr,   &version_string },
 531   { "headers_added",       vtype_string_func, &fn_hdrs_added },
 532   { "home",                vtype_stringptr,   &deliver_home },
 533   { "host",                vtype_stringptr,   &deliver_host },
 534   { "host_address",        vtype_stringptr,   &deliver_host_address },
 535   { "host_data",           vtype_stringptr,   &host_data },
 536   { "host_lookup_deferred",vtype_int,         &host_lookup_deferred },
 537   { "host_lookup_failed",  vtype_int,         &host_lookup_failed },
 538   { "host_port",           vtype_int,         &deliver_host_port },
 539   { "initial_cwd",         vtype_stringptr,   &initial_cwd },
 540   { "inode",               vtype_ino,         &deliver_inode },
 541   { "interface_address",   vtype_stringptr,   &interface_address },
 542   { "interface_port",      vtype_int,         &interface_port },
 543   { "item",                vtype_stringptr,   &iterate_item },
 544   #ifdef LOOKUP_LDAP
 545   { "ldap_dn",             vtype_stringptr,   &eldap_dn },
 546   #endif
 547   { "load_average",        vtype_load_avg,    NULL },
 548   { "local_part",          vtype_stringptr,   &deliver_localpart },
 549   { "local_part_data",     vtype_stringptr,   &deliver_localpart_data },
 550   { "local_part_prefix",   vtype_stringptr,   &deliver_localpart_prefix },
 551   { "local_part_suffix",   vtype_stringptr,   &deliver_localpart_suffix },
 552   { "local_scan_data",     vtype_stringptr,   &local_scan_data },
 553   { "local_user_gid",      vtype_gid,         &local_user_gid },
 554   { "local_user_uid",      vtype_uid,         &local_user_uid },
 555   { "localhost_number",    vtype_int,         &host_number },
 556   { "log_inodes",          vtype_pinodes,     (void *)FALSE },
 557   { "log_space",           vtype_pspace,      (void *)FALSE },
 558   { "lookup_dnssec_authenticated",vtype_stringptr,&lookup_dnssec_authenticated},
 559   { "mailstore_basename",  vtype_stringptr,   &mailstore_basename },
 560 #ifdef WITH_CONTENT_SCAN
 561   { "malware_name",        vtype_stringptr,   &malware_name },
 562 #endif
 563   { "max_received_linelength", vtype_int,     &max_received_linelength },
 564   { "message_age",         vtype_int,         &message_age },
 565   { "message_body",        vtype_msgbody,     &message_body },
 566   { "message_body_end",    vtype_msgbody_end, &message_body_end },
 567   { "message_body_size",   vtype_int,         &message_body_size },
 568   { "message_exim_id",     vtype_stringptr,   &message_id },
 569   { "message_headers",     vtype_msgheaders,  NULL },
 570   { "message_headers_raw", vtype_msgheaders_raw, NULL },
 571   { "message_id",          vtype_stringptr,   &message_id },
 572   { "message_linecount",   vtype_int,         &message_linecount },
 573   { "message_size",        vtype_int,         &message_size },
 574 #ifdef SUPPORT_I18N
 575   { "message_smtputf8",    vtype_bool,        &message_smtputf8 },
 576 #endif
 577 #ifdef WITH_CONTENT_SCAN
 578   { "mime_anomaly_level",  vtype_int,         &mime_anomaly_level },
 579   { "mime_anomaly_text",   vtype_stringptr,   &mime_anomaly_text },
 580   { "mime_boundary",       vtype_stringptr,   &mime_boundary },
 581   { "mime_charset",        vtype_stringptr,   &mime_charset },
 582   { "mime_content_description", vtype_stringptr, &mime_content_description },
 583   { "mime_content_disposition", vtype_stringptr, &mime_content_disposition },
 584   { "mime_content_id",     vtype_stringptr,   &mime_content_id },
 585   { "mime_content_size",   vtype_int,         &mime_content_size },
 586   { "mime_content_transfer_encoding",vtype_stringptr, &mime_content_transfer_encoding },
 587   { "mime_content_type",   vtype_stringptr,   &mime_content_type },
 588   { "mime_decoded_filename", vtype_stringptr, &mime_decoded_filename },
 589   { "mime_filename",       vtype_stringptr,   &mime_filename },
 590   { "mime_is_coverletter", vtype_int,         &mime_is_coverletter },
 591   { "mime_is_multipart",   vtype_int,         &mime_is_multipart },
 592   { "mime_is_rfc822",      vtype_int,         &mime_is_rfc822 },
 593   { "mime_part_count",     vtype_int,         &mime_part_count },
 594 #endif
 595   { "n0",                  vtype_filter_int,  &filter_n[0] },
 596   { "n1",                  vtype_filter_int,  &filter_n[1] },
 597   { "n2",                  vtype_filter_int,  &filter_n[2] },
 598   { "n3",                  vtype_filter_int,  &filter_n[3] },
 599   { "n4",                  vtype_filter_int,  &filter_n[4] },
 600   { "n5",                  vtype_filter_int,  &filter_n[5] },
 601   { "n6",                  vtype_filter_int,  &filter_n[6] },
 602   { "n7",                  vtype_filter_int,  &filter_n[7] },
 603   { "n8",                  vtype_filter_int,  &filter_n[8] },
 604   { "n9",                  vtype_filter_int,  &filter_n[9] },
 605   { "original_domain",     vtype_stringptr,   &deliver_domain_orig },
 606   { "original_local_part", vtype_stringptr,   &deliver_localpart_orig },
 607   { "originator_gid",      vtype_gid,         &originator_gid },
 608   { "originator_uid",      vtype_uid,         &originator_uid },
 609   { "parent_domain",       vtype_stringptr,   &deliver_domain_parent },
 610   { "parent_local_part",   vtype_stringptr,   &deliver_localpart_parent },
 611   { "pid",                 vtype_pid,         NULL },
 612 #ifndef DISABLE_PRDR
 613   { "prdr_requested",      vtype_bool,        &prdr_requested },
 614 #endif
 615   { "primary_hostname",    vtype_stringptr,   &primary_hostname },
 616 #if defined(SUPPORT_PROXY) || defined(SUPPORT_SOCKS)
 617   { "proxy_external_address",vtype_stringptr, &proxy_external_address },
 618   { "proxy_external_port", vtype_int,         &proxy_external_port },
 619   { "proxy_local_address", vtype_stringptr,   &proxy_local_address },
 620   { "proxy_local_port",    vtype_int,         &proxy_local_port },
 621   { "proxy_session",       vtype_bool,        &proxy_session },
 622 #endif
 623   { "prvscheck_address",   vtype_stringptr,   &prvscheck_address },
 624   { "prvscheck_keynum",    vtype_stringptr,   &prvscheck_keynum },
 625   { "prvscheck_result",    vtype_stringptr,   &prvscheck_result },
 626   { "qualify_domain",      vtype_stringptr,   &qualify_domain_sender },
 627   { "qualify_recipient",   vtype_stringptr,   &qualify_domain_recipient },
 628   { "rcpt_count",          vtype_int,         &rcpt_count },
 629   { "rcpt_defer_count",    vtype_int,         &rcpt_defer_count },
 630   { "rcpt_fail_count",     vtype_int,         &rcpt_fail_count },
 631   { "received_count",      vtype_int,         &received_count },
 632   { "received_for",        vtype_stringptr,   &received_for },
 633   { "received_ip_address", vtype_stringptr,   &interface_address },
 634   { "received_port",       vtype_int,         &interface_port },
 635   { "received_protocol",   vtype_stringptr,   &received_protocol },
 636   { "received_time",       vtype_int,         &received_time },
 637   { "recipient_data",      vtype_stringptr,   &recipient_data },
 638   { "recipient_verify_failure",vtype_stringptr,&recipient_verify_failure },
 639   { "recipients",          vtype_string_func, &fn_recipients },
 640   { "recipients_count",    vtype_int,         &recipients_count },
 641 #ifdef WITH_CONTENT_SCAN
 642   { "regex_match_string",  vtype_stringptr,   &regex_match_string },
 643 #endif
 644   { "reply_address",       vtype_reply,       NULL },
 645   { "return_path",         vtype_stringptr,   &return_path },
 646   { "return_size_limit",   vtype_int,         &bounce_return_size_limit },
 647   { "router_name",         vtype_stringptr,   &router_name },
 648   { "runrc",               vtype_int,         &runrc },
 649   { "self_hostname",       vtype_stringptr,   &self_hostname },
 650   { "sender_address",      vtype_stringptr,   &sender_address },
 651   { "sender_address_data", vtype_stringptr,   &sender_address_data },
 652   { "sender_address_domain", vtype_domain,    &sender_address },
 653   { "sender_address_local_part", vtype_localpart, &sender_address },
 654   { "sender_data",         vtype_stringptr,   &sender_data },
 655   { "sender_fullhost",     vtype_stringptr,   &sender_fullhost },
 656   { "sender_helo_dnssec",  vtype_bool,        &sender_helo_dnssec },
 657   { "sender_helo_name",    vtype_stringptr,   &sender_helo_name },
 658   { "sender_host_address", vtype_stringptr,   &sender_host_address },
 659   { "sender_host_authenticated",vtype_stringptr, &sender_host_authenticated },
 660   { "sender_host_dnssec",  vtype_bool,        &sender_host_dnssec },
 661   { "sender_host_name",    vtype_host_lookup, NULL },
 662   { "sender_host_port",    vtype_int,         &sender_host_port },
 663   { "sender_ident",        vtype_stringptr,   &sender_ident },
 664   { "sender_rate",         vtype_stringptr,   &sender_rate },
 665   { "sender_rate_limit",   vtype_stringptr,   &sender_rate_limit },
 666   { "sender_rate_period",  vtype_stringptr,   &sender_rate_period },
 667   { "sender_rcvhost",      vtype_stringptr,   &sender_rcvhost },
 668   { "sender_verify_failure",vtype_stringptr,  &sender_verify_failure },
 669   { "sending_ip_address",  vtype_stringptr,   &sending_ip_address },
 670   { "sending_port",        vtype_int,         &sending_port },
 671   { "smtp_active_hostname", vtype_stringptr,  &smtp_active_hostname },
 672   { "smtp_command",        vtype_stringptr,   &smtp_cmd_buffer },
 673   { "smtp_command_argument", vtype_stringptr, &smtp_cmd_argument },
 674   { "smtp_count_at_connection_start", vtype_int, &smtp_accept_count },
 675   { "smtp_notquit_reason", vtype_stringptr,   &smtp_notquit_reason },
 676   { "sn0",                 vtype_filter_int,  &filter_sn[0] },
 677   { "sn1",                 vtype_filter_int,  &filter_sn[1] },
 678   { "sn2",                 vtype_filter_int,  &filter_sn[2] },
 679   { "sn3",                 vtype_filter_int,  &filter_sn[3] },
 680   { "sn4",                 vtype_filter_int,  &filter_sn[4] },
 681   { "sn5",                 vtype_filter_int,  &filter_sn[5] },
 682   { "sn6",                 vtype_filter_int,  &filter_sn[6] },
 683   { "sn7",                 vtype_filter_int,  &filter_sn[7] },
 684   { "sn8",                 vtype_filter_int,  &filter_sn[8] },
 685   { "sn9",                 vtype_filter_int,  &filter_sn[9] },
 686 #ifdef WITH_CONTENT_SCAN
 687   { "spam_action",         vtype_stringptr,   &spam_action },
 688   { "spam_bar",            vtype_stringptr,   &spam_bar },
 689   { "spam_report",         vtype_stringptr,   &spam_report },
 690   { "spam_score",          vtype_stringptr,   &spam_score },
 691   { "spam_score_int",      vtype_stringptr,   &spam_score_int },
 692 #endif
 693 #ifdef EXPERIMENTAL_SPF
 694   { "spf_guess",           vtype_stringptr,   &spf_guess },
 695   { "spf_header_comment",  vtype_stringptr,   &spf_header_comment },
 696   { "spf_received",        vtype_stringptr,   &spf_received },
 697   { "spf_result",          vtype_stringptr,   &spf_result },
 698   { "spf_smtp_comment",    vtype_stringptr,   &spf_smtp_comment },
 699 #endif
 700   { "spool_directory",     vtype_stringptr,   &spool_directory },
 701   { "spool_inodes",        vtype_pinodes,     (void *)TRUE },
 702   { "spool_space",         vtype_pspace,      (void *)TRUE },
 703 #ifdef EXPERIMENTAL_SRS
 704   { "srs_db_address",      vtype_stringptr,   &srs_db_address },
 705   { "srs_db_key",          vtype_stringptr,   &srs_db_key },
 706   { "srs_orig_recipient",  vtype_stringptr,   &srs_orig_recipient },
 707   { "srs_orig_sender",     vtype_stringptr,   &srs_orig_sender },
 708   { "srs_recipient",       vtype_stringptr,   &srs_recipient },
 709   { "srs_status",          vtype_stringptr,   &srs_status },
 710 #endif
 711   { "thisaddress",         vtype_stringptr,   &filter_thisaddress },
 712
 713   /* The non-(in,out) variables are now deprecated */
 714   { "tls_bits",            vtype_int,         &tls_in.bits },
 715   { "tls_certificate_verified", vtype_int,    &tls_in.certificate_verified },
 716   { "tls_cipher",          vtype_stringptr,   &tls_in.cipher },
 717
 718   { "tls_in_bits",         vtype_int,         &tls_in.bits },
 719   { "tls_in_certificate_verified", vtype_int, &tls_in.certificate_verified },
 720   { "tls_in_cipher",       vtype_stringptr,   &tls_in.cipher },
 721   { "tls_in_ocsp",         vtype_int,         &tls_in.ocsp },
 722   { "tls_in_ourcert",      vtype_cert,        &tls_in.ourcert },
 723   { "tls_in_peercert",     vtype_cert,        &tls_in.peercert },
 724   { "tls_in_peerdn",       vtype_stringptr,   &tls_in.peerdn },
 725 #if defined(SUPPORT_TLS)
 726   { "tls_in_sni",          vtype_stringptr,   &tls_in.sni },
 727 #endif
 728   { "tls_out_bits",        vtype_int,         &tls_out.bits },
 729   { "tls_out_certificate_verified", vtype_int,&tls_out.certificate_verified },
 730   { "tls_out_cipher",      vtype_stringptr,   &tls_out.cipher },
 731 #ifdef EXPERIMENTAL_DANE
 732   { "tls_out_dane",        vtype_bool,        &tls_out.dane_verified },
 733 #endif
 734   { "tls_out_ocsp",        vtype_int,         &tls_out.ocsp },
 735   { "tls_out_ourcert",     vtype_cert,        &tls_out.ourcert },
 736   { "tls_out_peercert",    vtype_cert,        &tls_out.peercert },
 737   { "tls_out_peerdn",      vtype_stringptr,   &tls_out.peerdn },
 738 #if defined(SUPPORT_TLS)
 739   { "tls_out_sni",         vtype_stringptr,   &tls_out.sni },
 740 #endif
 741 #ifdef EXPERIMENTAL_DANE
 742   { "tls_out_tlsa_usage",  vtype_int,         &tls_out.tlsa_usage },
 743 #endif
 744
 745   { "tls_peerdn",          vtype_stringptr,   &tls_in.peerdn }, /* mind the alphabetical order! */
 746 #if defined(SUPPORT_TLS)
 747   { "tls_sni",             vtype_stringptr,   &tls_in.sni },    /* mind the alphabetical order! */
 748 #endif
 749
 750   { "tod_bsdinbox",        vtype_todbsdin,    NULL },
 751   { "tod_epoch",           vtype_tode,        NULL },
 752   { "tod_epoch_l",         vtype_todel,       NULL },
 753   { "tod_full",            vtype_todf,        NULL },
 754   { "tod_log",             vtype_todl,        NULL },
 755   { "tod_logfile",         vtype_todlf,       NULL },
 756   { "tod_zone",            vtype_todzone,     NULL },
 757   { "tod_zulu",            vtype_todzulu,     NULL },
 758   { "transport_name",      vtype_stringptr,   &transport_name },
 759   { "value",               vtype_stringptr,   &lookup_value },
 760   { "verify_mode",         vtype_stringptr,   &verify_mode },
 761   { "version_number",      vtype_stringptr,   &version_string },
 762   { "warn_message_delay",  vtype_stringptr,   &warnmsg_delay },
 763   { "warn_message_recipient",vtype_stringptr, &warnmsg_recipients },
 764   { "warn_message_recipients",vtype_stringptr,&warnmsg_recipients },
 765   { "warnmsg_delay",       vtype_stringptr,   &warnmsg_delay },
 766   { "warnmsg_recipient",   vtype_stringptr,   &warnmsg_recipients },
 767   { "warnmsg_recipients",  vtype_stringptr,   &warnmsg_recipients }
 768 };
 769
 770 static int var_table_size = nelem(var_table);
 771 static uschar var_buffer[256];
 772 static BOOL malformed_header;
 773
 774 /* For textual hashes */
 775
 776 static const char *hashcodes = "abcdefghijklmnopqrtsuvwxyz"
 777                                "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
 778                                "0123456789";
 779
 780 enum { HMAC_MD5, HMAC_SHA1 };
 781
 782 /* For numeric hashes */
 783
 784 static unsigned int prime[] = {
 785   2,   3,   5,   7,  11,  13,  17,  19,  23,  29,
 786  31,  37,  41,  43,  47,  53,  59,  61,  67,  71,
 787  73,  79,  83,  89,  97, 101, 103, 107, 109, 113};
 788
 789 /* For printing modes in symbolic form */
 790
 791 static uschar *mtable_normal[] =
 792   { US"---", US"--x", US"-w-", US"-wx", US"r--", US"r-x", US"rw-", US"rwx" };
 793
 794 static uschar *mtable_setid[] =
 795   { US"--S", US"--s", US"-wS", US"-ws", US"r-S", US"r-s", US"rwS", US"rws" };
 796
 797 static uschar *mtable_sticky[] =
 798   { US"--T", US"--t", US"-wT", US"-wt", US"r-T", US"r-t", US"rwT", US"rwt" };
 799
 800
 801
 802 /*************************************************
 803 *           Tables for UTF-8 support             *
 804 *************************************************/
 805
 806 /* Table of the number of extra characters, indexed by the first character
 807 masked with 0x3f. The highest number for a valid UTF-8 character is in fact
 808 0x3d. */
 809
 810 static uschar utf8_table1[] = {
 811   1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
 812   1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
 813   2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
 814   3,3,3,3,3,3,3,3,4,4,4,4,5,5,5,5 };
 815
 816 /* These are the masks for the data bits in the first byte of a character,
 817 indexed by the number of additional bytes. */
 818
 819 static int utf8_table2[] = { 0xff, 0x1f, 0x0f, 0x07, 0x03, 0x01};
 820
 821 /* Get the next UTF-8 character, advancing the pointer. */
 822
 823 #define GETUTF8INC(c, ptr) \
 824   c = *ptr++; \
 825   if ((c & 0xc0) == 0xc0) \
 826     { \
 827     int a = utf8_table1[c & 0x3f];  /* Number of additional bytes */ \
 828     int s = 6*a; \
 829     c = (c & utf8_table2[a]) << s; \
 830     while (a-- > 0) \
 831       { \
 832       s -= 6; \
 833       c |= (*ptr++ & 0x3f) << s; \
 834       } \
 835     }
 836
 837
 838 /*************************************************
 839 *           Binary chop search on a table        *
 840 *************************************************/
 841
 842 /* This is used for matching expansion items and operators.
 843
 844 Arguments:
 845   name        the name that is being sought
 846   table       the table to search
 847   table_size  the number of items in the table
 848
 849 Returns:      the offset in the table, or -1
 850 */
 851
 852 static int
 853 chop_match(uschar *name, uschar **table, int table_size)
 854 {
 855 uschar **bot = table;
 856 uschar **top = table + table_size;
 857
 858 while (top > bot)
 859   {
 860   uschar **mid = bot + (top - bot)/2;
 861   int c = Ustrcmp(name, *mid);
 862   if (c == 0) return mid - table;
 863   if (c > 0) bot = mid + 1; else top = mid;
 864   }
 865
 866 return -1;
 867 }
 868
 869
 870
 871 /*************************************************
 872 *          Check a condition string              *
 873 *************************************************/
 874
 875 /* This function is called to expand a string, and test the result for a "true"
 876 or "false" value. Failure of the expansion yields FALSE; logged unless it was a
 877 forced fail or lookup defer.
 878
 879 We used to release all store used, but this is not not safe due
 880 to ${dlfunc } and ${acl }.  In any case expand_string_internal()
 881 is reasonably careful to release what it can.
 882
 883 The actual false-value tests should be replicated for ECOND_BOOL_LAX.
 884
 885 Arguments:
 886   condition     the condition string
 887   m1            text to be incorporated in panic error
 888   m2            ditto
 889
 890 Returns:        TRUE if condition is met, FALSE if not
 891 */
 892
 893 BOOL
 894 expand_check_condition(uschar *condition, uschar *m1, uschar *m2)
 895 {
 896 int rc;
 897 uschar *ss = expand_string(condition);
 898 if (ss == NULL)
 899   {
 900   if (!expand_string_forcedfail && !search_find_defer)
 901     log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand condition \"%s\" "
 902       "for %s %s: %s", condition, m1, m2, expand_string_message);
 903   return FALSE;
 904   }
 905 rc = ss[0] != 0 && Ustrcmp(ss, "0") != 0 && strcmpic(ss, US"no") != 0 &&
 906   strcmpic(ss, US"false") != 0;
 907 return rc;
 908 }
 909
 910
 911
 912
 913 /*************************************************
 914 *        Pseudo-random number generation         *
 915 *************************************************/
 916
 917 /* Pseudo-random number generation.  The result is not "expected" to be
 918 cryptographically strong but not so weak that someone will shoot themselves
 919 in the foot using it as a nonce in some email header scheme or whatever
 920 weirdness they'll twist this into.  The result should ideally handle fork().
 921
 922 However, if we're stuck unable to provide this, then we'll fall back to
 923 appallingly bad randomness.
 924
 925 If SUPPORT_TLS is defined then this will not be used except as an emergency
 926 fallback.
 927
 928 Arguments:
 929   max       range maximum
 930 Returns     a random number in range [0, max-1]
 931 */
 932
 933 #ifdef SUPPORT_TLS
 934 # define vaguely_random_number vaguely_random_number_fallback
 935 #endif
 936 int
 937 vaguely_random_number(int max)
 938 {
 939 #ifdef SUPPORT_TLS
 940 # undef vaguely_random_number
 941 #endif
 942   static pid_t pid = 0;
 943   pid_t p2;
 944 #if defined(HAVE_SRANDOM) && !defined(HAVE_SRANDOMDEV)
 945   struct timeval tv;
 946 #endif
 947
 948   p2 = getpid();
 949   if (p2 != pid)
 950     {
 951     if (pid != 0)
 952       {
 953
 954 #ifdef HAVE_ARC4RANDOM
 955       /* cryptographically strong randomness, common on *BSD platforms, not
 956       so much elsewhere.  Alas. */
 957 #ifndef NOT_HAVE_ARC4RANDOM_STIR
 958       arc4random_stir();
 959 #endif
 960 #elif defined(HAVE_SRANDOM) || defined(HAVE_SRANDOMDEV)
 961 #ifdef HAVE_SRANDOMDEV
 962       /* uses random(4) for seeding */
 963       srandomdev();
 964 #else
 965       gettimeofday(&tv, NULL);
 966       srandom(tv.tv_sec | tv.tv_usec | getpid());
 967 #endif
 968 #else
 969       /* Poor randomness and no seeding here */
 970 #endif
 971
 972       }
 973     pid = p2;
 974     }
 975
 976 #ifdef HAVE_ARC4RANDOM
 977   return arc4random() % max;
 978 #elif defined(HAVE_SRANDOM) || defined(HAVE_SRANDOMDEV)
 979   return random() % max;
 980 #else
 981   /* This one returns a 16-bit number, definitely not crypto-strong */
 982   return random_number(max);
 983 #endif
 984 }
 985
 986
 987
 988
 989 /*************************************************
 990 *             Pick out a name from a string      *
 991 *************************************************/
 992
 993 /* If the name is too long, it is silently truncated.
 994
 995 Arguments:
 996   name      points to a buffer into which to put the name
 997   max       is the length of the buffer
 998   s         points to the first alphabetic character of the name
 999   extras    chars other than alphanumerics to permit
1000
1001 Returns:    pointer to the first character after the name
1002
1003 Note: The test for *s != 0 in the while loop is necessary because
1004 Ustrchr() yields non-NULL if the character is zero (which is not something
1005 I expected). */
1006
1007 static const uschar *
1008 read_name(uschar *name, int max, const uschar *s, uschar *extras)
1009 {
1010 int ptr = 0;
1011 while (*s != 0 && (isalnum(*s) || Ustrchr(extras, *s) != NULL))
1012   {
1013   if (ptr < max-1) name[ptr++] = *s;
1014   s++;
1015   }
1016 name[ptr] = 0;
1017 return s;
1018 }
1019
1020
1021
1022 /*************************************************
1023 *     Pick out the rest of a header name         *
1024 *************************************************/
1025
1026 /* A variable name starting $header_ (or just $h_ for those who like
1027 abbreviations) might not be the complete header name because headers can
1028 contain any printing characters in their names, except ':'. This function is
1029 called to read the rest of the name, chop h[eader]_ off the front, and put ':'
1030 on the end, if the name was terminated by white space.
1031
1032 Arguments:
1033   name      points to a buffer in which the name read so far exists
1034   max       is the length of the buffer
1035   s         points to the first character after the name so far, i.e. the
1036             first non-alphameric character after $header_xxxxx
1037
1038 Returns:    a pointer to the first character after the header name
1039 */
1040
1041 static const uschar *
1042 read_header_name(uschar *name, int max, const uschar *s)
1043 {
1044 int prelen = Ustrchr(name, '_') - name + 1;
1045 int ptr = Ustrlen(name) - prelen;
1046 if (ptr > 0) memmove(name, name+prelen, ptr);
1047 while (mac_isgraph(*s) && *s != ':')
1048   {
1049   if (ptr < max-1) name[ptr++] = *s;
1050   s++;
1051   }
1052 if (*s == ':') s++;
1053 name[ptr++] = ':';
1054 name[ptr] = 0;
1055 return s;
1056 }
1057
1058
1059
1060 /*************************************************
1061 *           Pick out a number from a string      *
1062 *************************************************/
1063
1064 /* Arguments:
1065   n     points to an integer into which to put the number
1066   s     points to the first digit of the number
1067
1068 Returns:  a pointer to the character after the last digit
1069 */
1070 /*XXX consider expanding to int_eximarith_t.  But the test for
1071 "overbig numbers" in 0002 still needs to overflow it. */
1072
1073 static uschar *
1074 read_number(int *n, uschar *s)
1075 {
1076 *n = 0;
1077 while (isdigit(*s)) *n = *n * 10 + (*s++ - '0');
1078 return s;
1079 }
1080
1081 static const uschar *
1082 read_cnumber(int *n, const uschar *s)
1083 {
1084 *n = 0;
1085 while (isdigit(*s)) *n = *n * 10 + (*s++ - '0');
1086 return s;
1087 }
1088
1089
1090
1091 /*************************************************
1092 *        Extract keyed subfield from a string    *
1093 *************************************************/
1094
1095 /* The yield is in dynamic store; NULL means that the key was not found.
1096
1097 Arguments:
1098   key       points to the name of the key
1099   s         points to the string from which to extract the subfield
1100
1101 Returns:    NULL if the subfield was not found, or
1102             a pointer to the subfield's data
1103 */
1104
1105 static uschar *
1106 expand_getkeyed(uschar *key, const uschar *s)
1107 {
1108 int length = Ustrlen(key);
1109 while (isspace(*s)) s++;
1110
1111 /* Loop to search for the key */
1112
1113 while (*s != 0)
1114   {
1115   int dkeylength;
1116   uschar *data;
1117   const uschar *dkey = s;
1118
1119   while (*s != 0 && *s != '=' && !isspace(*s)) s++;
1120   dkeylength = s - dkey;
1121   while (isspace(*s)) s++;
1122   if (*s == '=') while (isspace((*(++s))));
1123
1124   data = string_dequote(&s);
1125   if (length == dkeylength && strncmpic(key, dkey, length) == 0)
1126     return data;
1127
1128   while (isspace(*s)) s++;
1129   }
1130
1131 return NULL;
1132 }
1133
1134
1135
1136 static var_entry *
1137 find_var_ent(uschar * name)
1138 {
1139 int first = 0;
1140 int last = var_table_size;
1141
1142 while (last > first)
1143   {
1144   int middle = (first + last)/2;
1145   int c = Ustrcmp(name, var_table[middle].name);
1146
1147   if (c > 0) { first = middle + 1; continue; }
1148   if (c < 0) { last = middle; continue; }
1149   return &var_table[middle];
1150   }
1151 return NULL;
1152 }
1153
1154 /*************************************************
1155 *   Extract numbered subfield from string        *
1156 *************************************************/
1157
1158 /* Extracts a numbered field from a string that is divided by tokens - for
1159 example a line from /etc/passwd is divided by colon characters.  First field is
1160 numbered one.  Negative arguments count from the right. Zero returns the whole
1161 string. Returns NULL if there are insufficient tokens in the string
1162
1163 ***WARNING***
1164 Modifies final argument - this is a dynamically generated string, so that's OK.
1165
1166 Arguments:
1167   field       number of field to be extracted,
1168                 first field = 1, whole string = 0, last field = -1
1169   separators  characters that are used to break string into tokens
1170   s           points to the string from which to extract the subfield
1171
1172 Returns:      NULL if the field was not found,
1173               a pointer to the field's data inside s (modified to add 0)
1174 */
1175
1176 static uschar *
1177 expand_gettokened (int field, uschar *separators, uschar *s)
1178 {
1179 int sep = 1;
1180 int count;
1181 uschar *ss = s;
1182 uschar *fieldtext = NULL;
1183
1184 if (field == 0) return s;
1185
1186 /* Break the line up into fields in place; for field > 0 we stop when we have
1187 done the number of fields we want. For field < 0 we continue till the end of
1188 the string, counting the number of fields. */
1189
1190 count = (field > 0)? field : INT_MAX;
1191
1192 while (count-- > 0)
1193   {
1194   size_t len;
1195
1196   /* Previous field was the last one in the string. For a positive field
1197   number, this means there are not enough fields. For a negative field number,
1198   check that there are enough, and scan back to find the one that is wanted. */
1199
1200   if (sep == 0)
1201     {
1202     if (field > 0 || (-field) > (INT_MAX - count - 1)) return NULL;
1203     if ((-field) == (INT_MAX - count - 1)) return s;
1204     while (field++ < 0)
1205       {
1206       ss--;
1207       while (ss[-1] != 0) ss--;
1208       }
1209     fieldtext = ss;
1210     break;
1211     }
1212
1213   /* Previous field was not last in the string; save its start and put a
1214   zero at its end. */
1215
1216   fieldtext = ss;
1217   len = Ustrcspn(ss, separators);
1218   sep = ss[len];
1219   ss[len] = 0;
1220   ss += len + 1;
1221   }
1222
1223 return fieldtext;
1224 }
1225
1226
1227 static uschar *
1228 expand_getlistele(int field, const uschar * list)
1229 {
1230 const uschar * tlist= list;
1231 int sep= 0;
1232 uschar dummy;
1233
1234 if(field<0)
1235   {
1236   for(field++; string_nextinlist(&tlist, &sep, &dummy, 1); ) field++;
1237   sep= 0;
1238   }
1239 if(field==0) return NULL;
1240 while(--field>0 && (string_nextinlist(&list, &sep, &dummy, 1))) ;
1241 return string_nextinlist(&list, &sep, NULL, 0);
1242 }
1243
1244
1245 /* Certificate fields, by name.  Worry about by-OID later */
1246 /* Names are chosen to not have common prefixes */
1247
1248 #ifdef SUPPORT_TLS
1249 typedef struct
1250 {
1251 uschar * name;
1252 int      namelen;
1253 uschar * (*getfn)(void * cert, uschar * mod);
1254 } certfield;
1255 static certfield certfields[] =
1256 {                       /* linear search; no special order */
1257   { US"version",         7,  &tls_cert_version },
1258   { US"serial_number",   13, &tls_cert_serial_number },
1259   { US"subject",         7,  &tls_cert_subject },
1260   { US"notbefore",       9,  &tls_cert_not_before },
1261   { US"notafter",        8,  &tls_cert_not_after },
1262   { US"issuer",          6,  &tls_cert_issuer },
1263   { US"signature",       9,  &tls_cert_signature },
1264   { US"sig_algorithm",   13, &tls_cert_signature_algorithm },
1265   { US"subj_altname",    12, &tls_cert_subject_altname },
1266   { US"ocsp_uri",        8,  &tls_cert_ocsp_uri },
1267   { US"crl_uri",         7,  &tls_cert_crl_uri },
1268 };
1269
1270 static uschar *
1271 expand_getcertele(uschar * field, uschar * certvar)
1272 {
1273 var_entry * vp;
1274 certfield * cp;
1275
1276 if (!(vp = find_var_ent(certvar)))
1277   {
1278   expand_string_message =
1279     string_sprintf("no variable named \"%s\"", certvar);
1280   return NULL;          /* Unknown variable name */
1281   }
1282 /* NB this stops us passing certs around in variable.  Might
1283 want to do that in future */
1284 if (vp->type != vtype_cert)
1285   {
1286   expand_string_message =
1287     string_sprintf("\"%s\" is not a certificate", certvar);
1288   return NULL;          /* Unknown variable name */
1289   }
1290 if (!*(void **)vp->value)
1291   return NULL;
1292
1293 if (*field >= '0' && *field <= '9')
1294   return tls_cert_ext_by_oid(*(void **)vp->value, field, 0);
1295
1296 for(cp = certfields;
1297     cp < certfields + nelem(certfields);
1298     cp++)
1299   if (Ustrncmp(cp->name, field, cp->namelen) == 0)
1300     {
1301     uschar * modifier = *(field += cp->namelen) == ','
1302       ? ++field : NULL;
1303     return (*cp->getfn)( *(void **)vp->value, modifier );
1304     }
1305
1306 expand_string_message =
1307   string_sprintf("bad field selector \"%s\" for certextract", field);
1308 return NULL;
1309 }
1310 #endif  /*SUPPORT_TLS*/
1311
1312 /*************************************************
1313 *        Extract a substring from a string       *
1314 *************************************************/
1315
1316 /* Perform the ${substr or ${length expansion operations.
1317
1318 Arguments:
1319   subject     the input string
1320   value1      the offset from the start of the input string to the start of
1321                 the output string; if negative, count from the right.
1322   value2      the length of the output string, or negative (-1) for unset
1323                 if value1 is positive, unset means "all after"
1324                 if value1 is negative, unset means "all before"
1325   len         set to the length of the returned string
1326
1327 Returns:      pointer to the output string, or NULL if there is an error
1328 */
1329
1330 static uschar *
1331 extract_substr(uschar *subject, int value1, int value2, int *len)
1332 {
1333 int sublen = Ustrlen(subject);
1334
1335 if (value1 < 0)    /* count from right */
1336   {
1337   value1 += sublen;
1338
1339   /* If the position is before the start, skip to the start, and adjust the
1340   length. If the length ends up negative, the substring is null because nothing
1341   can precede. This falls out naturally when the length is unset, meaning "all
1342   to the left". */
1343
1344   if (value1 < 0)
1345     {
1346     value2 += value1;
1347     if (value2 < 0) value2 = 0;
1348     value1 = 0;
1349     }
1350
1351   /* Otherwise an unset length => characters before value1 */
1352
1353   else if (value2 < 0)
1354     {
1355     value2 = value1;
1356     value1 = 0;
1357     }
1358   }
1359
1360 /* For a non-negative offset, if the starting position is past the end of the
1361 string, the result will be the null string. Otherwise, an unset length means
1362 "rest"; just set it to the maximum - it will be cut down below if necessary. */
1363
1364 else
1365   {
1366   if (value1 > sublen)
1367     {
1368     value1 = sublen;
1369     value2 = 0;
1370     }
1371   else if (value2 < 0) value2 = sublen;
1372   }
1373
1374 /* Cut the length down to the maximum possible for the offset value, and get
1375 the required characters. */
1376
1377 if (value1 + value2 > sublen) value2 = sublen - value1;
1378 *len = value2;
1379 return subject + value1;
1380 }
1381
1382
1383
1384
1385 /*************************************************
1386 *            Old-style hash of a string          *
1387 *************************************************/
1388
1389 /* Perform the ${hash expansion operation.
1390
1391 Arguments:
1392   subject     the input string (an expanded substring)
1393   value1      the length of the output string; if greater or equal to the
1394                 length of the input string, the input string is returned
1395   value2      the number of hash characters to use, or 26 if negative
1396   len         set to the length of the returned string
1397
1398 Returns:      pointer to the output string, or NULL if there is an error
1399 */
1400
1401 static uschar *
1402 compute_hash(uschar *subject, int value1, int value2, int *len)
1403 {
1404 int sublen = Ustrlen(subject);
1405
1406 if (value2 < 0) value2 = 26;
1407 else if (value2 > Ustrlen(hashcodes))
1408   {
1409   expand_string_message =
1410     string_sprintf("hash count \"%d\" too big", value2);
1411   return NULL;
1412   }
1413
1414 /* Calculate the hash text. We know it is shorter than the original string, so
1415 can safely place it in subject[] (we know that subject is always itself an
1416 expanded substring). */
1417
1418 if (value1 < sublen)
1419   {
1420   int c;
1421   int i = 0;
1422   int j = value1;
1423   while ((c = (subject[j])) != 0)
1424     {
1425     int shift = (c + j++) & 7;
1426     subject[i] ^= (c << shift) | (c >> (8-shift));
1427     if (++i >= value1) i = 0;
1428     }
1429   for (i = 0; i < value1; i++)
1430     subject[i] = hashcodes[(subject[i]) % value2];
1431   }
1432 else value1 = sublen;
1433
1434 *len = value1;
1435 return subject;
1436 }
1437
1438
1439
1440
1441 /*************************************************
1442 *             Numeric hash of a string           *
1443 *************************************************/
1444
1445 /* Perform the ${nhash expansion operation. The first characters of the
1446 string are treated as most important, and get the highest prime numbers.
1447
1448 Arguments:
1449   subject     the input string
1450   value1      the maximum value of the first part of the result
1451   value2      the maximum value of the second part of the result,
1452                 or negative to produce only a one-part result
1453   len         set to the length of the returned string
1454
1455 Returns:  pointer to the output string, or NULL if there is an error.
1456 */
1457
1458 static uschar *
1459 compute_nhash (uschar *subject, int value1, int value2, int *len)
1460 {
1461 uschar *s = subject;
1462 int i = 0;
1463 unsigned long int total = 0; /* no overflow */
1464
1465 while (*s != 0)
1466   {
1467   if (i == 0) i = nelem(prime) - 1;
1468   total += prime[i--] * (unsigned int)(*s++);
1469   }
1470
1471 /* If value2 is unset, just compute one number */
1472
1473 if (value2 < 0)
1474   {
1475   s = string_sprintf("%d", total % value1);
1476   }
1477
1478 /* Otherwise do a div/mod hash */
1479
1480 else
1481   {
1482   total = total % (value1 * value2);
1483   s = string_sprintf("%d/%d", total/value2, total % value2);
1484   }
1485
1486 *len = Ustrlen(s);
1487 return s;
1488 }
1489
1490
1491
1492
1493
1494 /*************************************************
1495 *     Find the value of a header or headers      *
1496 *************************************************/
1497
1498 /* Multiple instances of the same header get concatenated, and this function
1499 can also return a concatenation of all the header lines. When concatenating
1500 specific headers that contain lists of addresses, a comma is inserted between
1501 them. Otherwise we use a straight concatenation. Because some messages can have
1502 pathologically large number of lines, there is a limit on the length that is
1503 returned. Also, to avoid massive store use which would result from using
1504 string_cat() as it copies and extends strings, we do a preliminary pass to find
1505 out exactly how much store will be needed. On "normal" messages this will be
1506 pretty trivial.
1507
1508 Arguments:
1509   name          the name of the header, without the leading $header_ or $h_,
1510                 or NULL if a concatenation of all headers is required
1511   exists_only   TRUE if called from a def: test; don't need to build a string;
1512                 just return a string that is not "" and not "0" if the header
1513                 exists
1514   newsize       return the size of memory block that was obtained; may be NULL
1515                 if exists_only is TRUE
1516   want_raw      TRUE if called for $rh_ or $rheader_ variables; no processing,
1517                 other than concatenating, will be done on the header. Also used
1518                 for $message_headers_raw.
1519   charset       name of charset to translate MIME words to; used only if
1520                 want_raw is false; if NULL, no translation is done (this is
1521                 used for $bh_ and $bheader_)
1522
1523 Returns:        NULL if the header does not exist, else a pointer to a new
1524                 store block
1525 */
1526
1527 static uschar *
1528 find_header(uschar *name, BOOL exists_only, int *newsize, BOOL want_raw,
1529   uschar *charset)
1530 {
1531 BOOL found = name == NULL;
1532 int comma = 0;
1533 int len = found? 0 : Ustrlen(name);
1534 int i;
1535 uschar *yield = NULL;
1536 uschar *ptr = NULL;
1537
1538 /* Loop for two passes - saves code repetition */
1539
1540 for (i = 0; i < 2; i++)
1541   {
1542   int size = 0;
1543   header_line *h;
1544
1545   for (h = header_list; size < header_insert_maxlen && h != NULL; h = h->next)
1546     {
1547     if (h->type != htype_old && h->text != NULL)  /* NULL => Received: placeholder */
1548       {
1549       if (name == NULL || (len <= h->slen && strncmpic(name, h->text, len) == 0))
1550         {
1551         int ilen;
1552         uschar *t;
1553
1554         if (exists_only) return US"1";      /* don't need actual string */
1555         found = TRUE;
1556         t = h->text + len;                  /* text to insert */
1557         if (!want_raw)                      /* unless wanted raw, */
1558           while (isspace(*t)) t++;          /* remove leading white space */
1559         ilen = h->slen - (t - h->text);     /* length to insert */
1560
1561         /* Unless wanted raw, remove trailing whitespace, including the
1562         newline. */
1563
1564         if (!want_raw)
1565           while (ilen > 0 && isspace(t[ilen-1])) ilen--;
1566
1567         /* Set comma = 1 if handling a single header and it's one of those
1568         that contains an address list, except when asked for raw headers. Only
1569         need to do this once. */
1570
1571         if (!want_raw && name != NULL && comma == 0 &&
1572             Ustrchr("BCFRST", h->type) != NULL)
1573           comma = 1;
1574
1575         /* First pass - compute total store needed; second pass - compute
1576         total store used, including this header. */
1577
1578         size += ilen + comma + 1;  /* +1 for the newline */
1579
1580         /* Second pass - concatentate the data, up to a maximum. Note that
1581         the loop stops when size hits the limit. */
1582
1583         if (i != 0)
1584           {
1585           if (size > header_insert_maxlen)
1586             {
1587             ilen -= size - header_insert_maxlen - 1;
1588             comma = 0;
1589             }
1590           Ustrncpy(ptr, t, ilen);
1591           ptr += ilen;
1592
1593           /* For a non-raw header, put in the comma if needed, then add
1594           back the newline we removed above, provided there was some text in
1595           the header. */
1596
1597           if (!want_raw && ilen > 0)
1598             {
1599             if (comma != 0) *ptr++ = ',';
1600             *ptr++ = '\n';
1601             }
1602           }
1603         }
1604       }
1605     }
1606
1607   /* At end of first pass, return NULL if no header found. Then truncate size
1608   if necessary, and get the buffer to hold the data, returning the buffer size.
1609   */
1610
1611   if (i == 0)
1612     {
1613     if (!found) return NULL;
1614     if (size > header_insert_maxlen) size = header_insert_maxlen;
1615     *newsize = size + 1;
1616     ptr = yield = store_get(*newsize);
1617     }
1618   }
1619
1620 /* That's all we do for raw header expansion. */
1621
1622 if (want_raw)
1623   {
1624   *ptr = 0;
1625   }
1626
1627 /* Otherwise, remove a final newline and a redundant added comma. Then we do
1628 RFC 2047 decoding, translating the charset if requested. The rfc2047_decode2()
1629 function can return an error with decoded data if the charset translation
1630 fails. If decoding fails, it returns NULL. */
1631
1632 else
1633   {
1634   uschar *decoded, *error;
1635   if (ptr > yield && ptr[-1] == '\n') ptr--;
1636   if (ptr > yield && comma != 0 && ptr[-1] == ',') ptr--;
1637   *ptr = 0;
1638   decoded = rfc2047_decode2(yield, check_rfc2047_length, charset, '?', NULL,
1639     newsize, &error);
1640   if (error != NULL)
1641     {
1642     DEBUG(D_any) debug_printf("*** error in RFC 2047 decoding: %s\n"
1643       "    input was: %s\n", error, yield);
1644     }
1645   if (decoded != NULL) yield = decoded;
1646   }
1647
1648 return yield;
1649 }
1650
1651
1652
1653
1654 /*************************************************
1655 *               Return list of recipients        *
1656 *************************************************/
1657 /* A recipients list is available only during system message filtering,
1658 during ACL processing after DATA, and while expanding pipe commands
1659 generated from a system filter, but not elsewhere. */
1660
1661 static uschar *
1662 fn_recipients(void)
1663 {
1664 if (!enable_dollar_recipients) return NULL; else
1665   {
1666   int size = 128;
1667   int ptr = 0;
1668   int i;
1669   uschar * s = store_get(size);
1670   for (i = 0; i < recipients_count; i++)
1671     {
1672     if (i != 0) s = string_catn(s, &size, &ptr, US", ", 2);
1673     s = string_cat(s, &size, &ptr, recipients_list[i].address);
1674     }
1675   s[ptr] = 0;     /* string_cat() leaves room */
1676   return s;
1677   }
1678 }
1679
1680
1681 /*************************************************
1682 *               Find value of a variable         *
1683 *************************************************/
1684
1685 /* The table of variables is kept in alphabetic order, so we can search it
1686 using a binary chop. The "choplen" variable is nothing to do with the binary
1687 chop.
1688
1689 Arguments:
1690   name          the name of the variable being sought
1691   exists_only   TRUE if this is a def: test; passed on to find_header()
1692   skipping      TRUE => skip any processing evaluation; this is not the same as
1693                   exists_only because def: may test for values that are first
1694                   evaluated here
1695   newsize       pointer to an int which is initially zero; if the answer is in
1696                 a new memory buffer, *newsize is set to its size
1697
1698 Returns:        NULL if the variable does not exist, or
1699                 a pointer to the variable's contents, or
1700                 something non-NULL if exists_only is TRUE
1701 */
1702
1703 static uschar *
1704 find_variable(uschar *name, BOOL exists_only, BOOL skipping, int *newsize)
1705 {
1706 var_entry * vp;
1707 uschar *s, *domain;
1708 uschar **ss;
1709 void * val;
1710
1711 /* Handle ACL variables, whose names are of the form acl_cxxx or acl_mxxx.
1712 Originally, xxx had to be a number in the range 0-9 (later 0-19), but from
1713 release 4.64 onwards arbitrary names are permitted, as long as the first 5
1714 characters are acl_c or acl_m and the sixth is either a digit or an underscore
1715 (this gave backwards compatibility at the changeover). There may be built-in
1716 variables whose names start acl_ but they should never start in this way. This
1717 slightly messy specification is a consequence of the history, needless to say.
1718
1719 If an ACL variable does not exist, treat it as empty, unless strict_acl_vars is
1720 set, in which case give an error. */
1721
1722 if ((Ustrncmp(name, "acl_c", 5) == 0 || Ustrncmp(name, "acl_m", 5) == 0) &&
1723      !isalpha(name[5]))
1724   {
1725   tree_node *node =
1726     tree_search((name[4] == 'c')? acl_var_c : acl_var_m, name + 4);
1727   return node ? node->data.ptr : strict_acl_vars ? NULL : US"";
1728   }
1729
1730 /* Handle $auth<n> variables. */
1731
1732 if (Ustrncmp(name, "auth", 4) == 0)
1733   {
1734   uschar *endptr;
1735   int n = Ustrtoul(name + 4, &endptr, 10);
1736   if (*endptr == 0 && n != 0 && n <= AUTH_VARS)
1737     return !auth_vars[n-1] ? US"" : auth_vars[n-1];
1738   }
1739 else if (Ustrncmp(name, "regex", 5) == 0)
1740   {
1741   uschar *endptr;
1742   int n = Ustrtoul(name + 5, &endptr, 10);
1743   if (*endptr == 0 && n != 0 && n <= REGEX_VARS)
1744     return !regex_vars[n-1] ? US"" : regex_vars[n-1];
1745   }
1746
1747 /* For all other variables, search the table */
1748
1749 if (!(vp = find_var_ent(name)))
1750   return NULL;          /* Unknown variable name */
1751
1752 /* Found an existing variable. If in skipping state, the value isn't needed,
1753 and we want to avoid processing (such as looking up the host name). */
1754
1755 if (skipping)
1756   return US"";
1757
1758 val = vp->value;
1759 switch (vp->type)
1760   {
1761   case vtype_filter_int:
1762     if (!filter_running) return NULL;
1763     /* Fall through */
1764     /* VVVVVVVVVVVV */
1765   case vtype_int:
1766     sprintf(CS var_buffer, "%d", *(int *)(val)); /* Integer */
1767     return var_buffer;
1768
1769   case vtype_ino:
1770     sprintf(CS var_buffer, "%ld", (long int)(*(ino_t *)(val))); /* Inode */
1771     return var_buffer;
1772
1773   case vtype_gid:
1774     sprintf(CS var_buffer, "%ld", (long int)(*(gid_t *)(val))); /* gid */
1775     return var_buffer;
1776
1777   case vtype_uid:
1778     sprintf(CS var_buffer, "%ld", (long int)(*(uid_t *)(val))); /* uid */
1779     return var_buffer;
1780
1781   case vtype_bool:
1782     sprintf(CS var_buffer, "%s", *(BOOL *)(val) ? "yes" : "no"); /* bool */
1783     return var_buffer;
1784
1785   case vtype_stringptr:                      /* Pointer to string */
1786     return (s = *((uschar **)(val))) ? s : US"";
1787
1788   case vtype_pid:
1789     sprintf(CS var_buffer, "%d", (int)getpid()); /* pid */
1790     return var_buffer;
1791
1792   case vtype_load_avg:
1793     sprintf(CS var_buffer, "%d", OS_GETLOADAVG()); /* load_average */
1794     return var_buffer;
1795
1796   case vtype_host_lookup:                    /* Lookup if not done so */
1797     if (sender_host_name == NULL && sender_host_address != NULL &&
1798         !host_lookup_failed && host_name_lookup() == OK)
1799       host_build_sender_fullhost();
1800     return (sender_host_name == NULL)? US"" : sender_host_name;
1801
1802   case vtype_localpart:                      /* Get local part from address */
1803     s = *((uschar **)(val));
1804     if (s == NULL) return US"";
1805     domain = Ustrrchr(s, '@');
1806     if (domain == NULL) return s;
1807     if (domain - s > sizeof(var_buffer) - 1)
1808       log_write(0, LOG_MAIN|LOG_PANIC_DIE, "local part longer than " SIZE_T_FMT
1809           " in string expansion", sizeof(var_buffer));
1810     Ustrncpy(var_buffer, s, domain - s);
1811     var_buffer[domain - s] = 0;
1812     return var_buffer;
1813
1814   case vtype_domain:                         /* Get domain from address */
1815     s = *((uschar **)(val));
1816     if (s == NULL) return US"";
1817     domain = Ustrrchr(s, '@');
1818     return (domain == NULL)? US"" : domain + 1;
1819
1820   case vtype_msgheaders:
1821     return find_header(NULL, exists_only, newsize, FALSE, NULL);
1822
1823   case vtype_msgheaders_raw:
1824     return find_header(NULL, exists_only, newsize, TRUE, NULL);
1825
1826   case vtype_msgbody:                        /* Pointer to msgbody string */
1827   case vtype_msgbody_end:                    /* Ditto, the end of the msg */
1828     ss = (uschar **)(val);
1829     if (*ss == NULL && deliver_datafile >= 0)  /* Read body when needed */
1830       {
1831       uschar *body;
1832       off_t start_offset = SPOOL_DATA_START_OFFSET;
1833       int len = message_body_visible;
1834       if (len > message_size) len = message_size;
1835       *ss = body = store_malloc(len+1);
1836       body[0] = 0;
1837       if (vp->type == vtype_msgbody_end)
1838         {
1839         struct stat statbuf;
1840         if (fstat(deliver_datafile, &statbuf) == 0)
1841           {
1842           start_offset = statbuf.st_size - len;
1843           if (start_offset < SPOOL_DATA_START_OFFSET)
1844             start_offset = SPOOL_DATA_START_OFFSET;
1845           }
1846         }
1847       if (lseek(deliver_datafile, start_offset, SEEK_SET) < 0)
1848         log_write(0, LOG_MAIN|LOG_PANIC_DIE, "deliver_datafile lseek: %s",
1849           strerror(errno));
1850       len = read(deliver_datafile, body, len);
1851       if (len > 0)
1852         {
1853         body[len] = 0;
1854         if (message_body_newlines)   /* Separate loops for efficiency */
1855           while (len > 0)
1856             { if (body[--len] == 0) body[len] = ' '; }
1857         else
1858           while (len > 0)
1859             { if (body[--len] == '\n' || body[len] == 0) body[len] = ' '; }
1860         }
1861       }
1862     return (*ss == NULL)? US"" : *ss;
1863
1864   case vtype_todbsdin:                       /* BSD inbox time of day */
1865     return tod_stamp(tod_bsdin);
1866
1867   case vtype_tode:                           /* Unix epoch time of day */
1868     return tod_stamp(tod_epoch);
1869
1870   case vtype_todel:                          /* Unix epoch/usec time of day */
1871     return tod_stamp(tod_epoch_l);
1872
1873   case vtype_todf:                           /* Full time of day */
1874     return tod_stamp(tod_full);
1875
1876   case vtype_todl:                           /* Log format time of day */
1877     return tod_stamp(tod_log_bare);            /* (without timezone) */
1878
1879   case vtype_todzone:                        /* Time zone offset only */
1880     return tod_stamp(tod_zone);
1881
1882   case vtype_todzulu:                        /* Zulu time */
1883     return tod_stamp(tod_zulu);
1884
1885   case vtype_todlf:                          /* Log file datestamp tod */
1886     return tod_stamp(tod_log_datestamp_daily);
1887
1888   case vtype_reply:                          /* Get reply address */
1889     s = find_header(US"reply-to:", exists_only, newsize, TRUE,
1890       headers_charset);
1891     if (s != NULL) while (isspace(*s)) s++;
1892     if (s == NULL || *s == 0)
1893       {
1894       *newsize = 0;                            /* For the *s==0 case */
1895       s = find_header(US"from:", exists_only, newsize, TRUE, headers_charset);
1896       }
1897     if (s != NULL)
1898       {
1899       uschar *t;
1900       while (isspace(*s)) s++;
1901       for (t = s; *t != 0; t++) if (*t == '\n') *t = ' ';
1902       while (t > s && isspace(t[-1])) t--;
1903       *t = 0;
1904       }
1905     return (s == NULL)? US"" : s;
1906
1907   case vtype_string_func:
1908     {
1909     uschar * (*fn)() = val;
1910     return fn();
1911     }
1912
1913   case vtype_pspace:
1914     {
1915     int inodes;
1916     sprintf(CS var_buffer, "%d",
1917       receive_statvfs(val == (void *)TRUE, &inodes));
1918     }
1919   return var_buffer;
1920
1921   case vtype_pinodes:
1922     {
1923     int inodes;
1924     (void) receive_statvfs(val == (void *)TRUE, &inodes);
1925     sprintf(CS var_buffer, "%d", inodes);
1926     }
1927   return var_buffer;
1928
1929   case vtype_cert:
1930     return *(void **)val ? US"<cert>" : US"";
1931
1932 #ifndef DISABLE_DKIM
1933   case vtype_dkim:
1934     return dkim_exim_expand_query((int)(long)val);
1935 #endif
1936
1937   }
1938
1939 return NULL;  /* Unknown variable. Silences static checkers. */
1940 }
1941
1942
1943
1944
1945 void
1946 modify_variable(uschar *name, void * value)
1947 {
1948 var_entry * vp;
1949 if ((vp = find_var_ent(name))) vp->value = value;
1950 return;          /* Unknown variable name, fail silently */
1951 }
1952
1953
1954
1955
1956
1957 /*************************************************
1958 *           Read and expand substrings           *
1959 *************************************************/
1960
1961 /* This function is called to read and expand argument substrings for various
1962 expansion items. Some have a minimum requirement that is less than the maximum;
1963 in these cases, the first non-present one is set to NULL.
1964
1965 Arguments:
1966   sub        points to vector of pointers to set
1967   n          maximum number of substrings
1968   m          minimum required
1969   sptr       points to current string pointer
1970   skipping   the skipping flag
1971   check_end  if TRUE, check for final '}'
1972   name       name of item, for error message
1973   resetok    if not NULL, pointer to flag - write FALSE if unsafe to reset
1974              the store.
1975
1976 Returns:     0 OK; string pointer updated
1977              1 curly bracketing error (too few arguments)
1978              2 too many arguments (only if check_end is set); message set
1979              3 other error (expansion failure)
1980 */
1981
1982 static int
1983 read_subs(uschar **sub, int n, int m, const uschar **sptr, BOOL skipping,
1984   BOOL check_end, uschar *name, BOOL *resetok)
1985 {
1986 int i;
1987 const uschar *s = *sptr;
1988
1989 while (isspace(*s)) s++;
1990 for (i = 0; i < n; i++)
1991   {
1992   if (*s != '{')
1993     {
1994     if (i < m)
1995       {
1996       expand_string_message = string_sprintf("Not enough arguments for '%s' "
1997         "(min is %d)", name, m);
1998       return 1;
1999       }
2000     sub[i] = NULL;
2001     break;
2002     }
2003   if (!(sub[i] = expand_string_internal(s+1, TRUE, &s, skipping, TRUE, resetok)))
2004     return 3;
2005   if (*s++ != '}') return 1;
2006   while (isspace(*s)) s++;
2007   }
2008 if (check_end && *s++ != '}')
2009   {
2010   if (s[-1] == '{')
2011     {
2012     expand_string_message = string_sprintf("Too many arguments for '%s' "
2013       "(max is %d)", name, n);
2014     return 2;
2015     }
2016   expand_string_message = string_sprintf("missing '}' after '%s'", name);
2017   return 1;
2018   }
2019
2020 *sptr = s;
2021 return 0;
2022 }
2023
2024
2025
2026
2027 /*************************************************
2028 *     Elaborate message for bad variable         *
2029 *************************************************/
2030
2031 /* For the "unknown variable" message, take a look at the variable's name, and
2032 give additional information about possible ACL variables. The extra information
2033 is added on to expand_string_message.
2034
2035 Argument:   the name of the variable
2036 Returns:    nothing
2037 */
2038
2039 static void
2040 check_variable_error_message(uschar *name)
2041 {
2042 if (Ustrncmp(name, "acl_", 4) == 0)
2043   expand_string_message = string_sprintf("%s (%s)", expand_string_message,
2044     (name[4] == 'c' || name[4] == 'm')?
2045       (isalpha(name[5])?
2046         US"6th character of a user-defined ACL variable must be a digit or underscore" :
2047         US"strict_acl_vars is set"    /* Syntax is OK, it has to be this */
2048       ) :
2049       US"user-defined ACL variables must start acl_c or acl_m");
2050 }
2051
2052
2053
2054 /*
2055 Load args from sub array to globals, and call acl_check().
2056 Sub array will be corrupted on return.
2057
2058 Returns:       OK         access is granted by an ACCEPT verb
2059                DISCARD    access is (apparently) granted by a DISCARD verb
2060                FAIL       access is denied
2061                FAIL_DROP  access is denied; drop the connection
2062                DEFER      can't tell at the moment
2063                ERROR      disaster
2064 */
2065 static int
2066 eval_acl(uschar ** sub, int nsub, uschar ** user_msgp)
2067 {
2068 int i;
2069 int sav_narg = acl_narg;
2070 int ret;
2071 uschar * dummy_logmsg;
2072 extern int acl_where;
2073
2074 if(--nsub > nelem(acl_arg)) nsub = nelem(acl_arg);
2075 for (i = 0; i < nsub && sub[i+1]; i++)
2076   {
2077   uschar * tmp = acl_arg[i];
2078   acl_arg[i] = sub[i+1];        /* place callers args in the globals */
2079   sub[i+1] = tmp;               /* stash the old args using our caller's storage */
2080   }
2081 acl_narg = i;
2082 while (i < nsub)
2083   {
2084   sub[i+1] = acl_arg[i];
2085   acl_arg[i++] = NULL;
2086   }
2087
2088 DEBUG(D_expand)
2089   debug_printf("expanding: acl: %s  arg: %s%s\n",
2090     sub[0],
2091     acl_narg>0 ? acl_arg[0] : US"<none>",
2092     acl_narg>1 ? " +more"   : "");
2093
2094 ret = acl_eval(acl_where, sub[0], user_msgp, &dummy_logmsg);
2095
2096 for (i = 0; i < nsub; i++)
2097   acl_arg[i] = sub[i+1];        /* restore old args */
2098 acl_narg = sav_narg;
2099
2100 return ret;
2101 }
2102
2103
2104
2105
2106 /*************************************************
2107 *        Read and evaluate a condition           *
2108 *************************************************/
2109
2110 /*
2111 Arguments:
2112   s        points to the start of the condition text
2113   resetok  points to a BOOL which is written false if it is unsafe to
2114            free memory. Certain condition types (acl) may have side-effect
2115            allocation which must be preserved.
2116   yield    points to a BOOL to hold the result of the condition test;
2117            if NULL, we are just reading through a condition that is
2118            part of an "or" combination to check syntax, or in a state
2119            where the answer isn't required
2120
2121 Returns:   a pointer to the first character after the condition, or
2122            NULL after an error
2123 */
2124
2125 static const uschar *
2126 eval_condition(const uschar *s, BOOL *resetok, BOOL *yield)
2127 {
2128 BOOL testfor = TRUE;
2129 BOOL tempcond, combined_cond;
2130 BOOL *subcondptr;
2131 BOOL sub2_honour_dollar = TRUE;
2132 int i, rc, cond_type, roffset;
2133 int_eximarith_t num[2];
2134 struct stat statbuf;
2135 uschar name[256];
2136 const uschar *sub[10];
2137
2138 const pcre *re;
2139 const uschar *rerror;
2140
2141 for (;;)
2142   {
2143   while (isspace(*s)) s++;
2144   if (*s == '!') { testfor = !testfor; s++; } else break;
2145   }
2146
2147 /* Numeric comparisons are symbolic */
2148
2149 if (*s == '=' || *s == '>' || *s == '<')
2150   {
2151   int p = 0;
2152   name[p++] = *s++;
2153   if (*s == '=')
2154     {
2155     name[p++] = '=';
2156     s++;
2157     }
2158   name[p] = 0;
2159   }
2160
2161 /* All other conditions are named */
2162
2163 else s = read_name(name, 256, s, US"_");
2164
2165 /* If we haven't read a name, it means some non-alpha character is first. */
2166
2167 if (name[0] == 0)
2168   {
2169   expand_string_message = string_sprintf("condition name expected, "
2170     "but found \"%.16s\"", s);
2171   return NULL;
2172   }
2173
2174 /* Find which condition we are dealing with, and switch on it */
2175
2176 cond_type = chop_match(name, cond_table, nelem(cond_table));
2177 switch(cond_type)
2178   {
2179   /* def: tests for a non-empty variable, or for the existence of a header. If
2180   yield == NULL we are in a skipping state, and don't care about the answer. */
2181
2182   case ECOND_DEF:
2183   if (*s != ':')
2184     {
2185     expand_string_message = US"\":\" expected after \"def\"";
2186     return NULL;
2187     }
2188
2189   s = read_name(name, 256, s+1, US"_");
2190
2191   /* Test for a header's existence. If the name contains a closing brace
2192   character, this may be a user error where the terminating colon has been
2193   omitted. Set a flag to adjust a subsequent error message in this case. */
2194
2195   if (Ustrncmp(name, "h_", 2) == 0 ||
2196       Ustrncmp(name, "rh_", 3) == 0 ||
2197       Ustrncmp(name, "bh_", 3) == 0 ||
2198       Ustrncmp(name, "header_", 7) == 0 ||
2199       Ustrncmp(name, "rheader_", 8) == 0 ||
2200       Ustrncmp(name, "bheader_", 8) == 0)
2201     {
2202     s = read_header_name(name, 256, s);
2203     /* {-for-text-editors */
2204     if (Ustrchr(name, '}') != NULL) malformed_header = TRUE;
2205     if (yield != NULL) *yield =
2206       (find_header(name, TRUE, NULL, FALSE, NULL) != NULL) == testfor;
2207     }
2208
2209   /* Test for a variable's having a non-empty value. A non-existent variable
2210   causes an expansion failure. */
2211
2212   else
2213     {
2214     uschar *value = find_variable(name, TRUE, yield == NULL, NULL);
2215     if (value == NULL)
2216       {
2217       expand_string_message = (name[0] == 0)?
2218         string_sprintf("variable name omitted after \"def:\"") :
2219         string_sprintf("unknown variable \"%s\" after \"def:\"", name);
2220       check_variable_error_message(name);
2221       return NULL;
2222       }
2223     if (yield != NULL) *yield = (value[0] != 0) == testfor;
2224     }
2225
2226   return s;
2227
2228
2229   /* first_delivery tests for first delivery attempt */
2230
2231   case ECOND_FIRST_DELIVERY:
2232   if (yield != NULL) *yield = deliver_firsttime == testfor;
2233   return s;
2234
2235
2236   /* queue_running tests for any process started by a queue runner */
2237
2238   case ECOND_QUEUE_RUNNING:
2239   if (yield != NULL) *yield = (queue_run_pid != (pid_t)0) == testfor;
2240   return s;
2241
2242
2243   /* exists:  tests for file existence
2244        isip:  tests for any IP address
2245       isip4:  tests for an IPv4 address
2246       isip6:  tests for an IPv6 address
2247         pam:  does PAM authentication
2248      radius:  does RADIUS authentication
2249    ldapauth:  does LDAP authentication
2250     pwcheck:  does Cyrus SASL pwcheck authentication
2251   */
2252
2253   case ECOND_EXISTS:
2254   case ECOND_ISIP:
2255   case ECOND_ISIP4:
2256   case ECOND_ISIP6:
2257   case ECOND_PAM:
2258   case ECOND_RADIUS:
2259   case ECOND_LDAPAUTH:
2260   case ECOND_PWCHECK:
2261
2262   while (isspace(*s)) s++;
2263   if (*s != '{') goto COND_FAILED_CURLY_START;          /* }-for-text-editors */
2264
2265   sub[0] = expand_string_internal(s+1, TRUE, &s, yield == NULL, TRUE, resetok);
2266   if (sub[0] == NULL) return NULL;
2267   /* {-for-text-editors */
2268   if (*s++ != '}') goto COND_FAILED_CURLY_END;
2269
2270   if (yield == NULL) return s;   /* No need to run the test if skipping */
2271
2272   switch(cond_type)
2273     {
2274     case ECOND_EXISTS:
2275     if ((expand_forbid & RDO_EXISTS) != 0)
2276       {
2277       expand_string_message = US"File existence tests are not permitted";
2278       return NULL;
2279       }
2280     *yield = (Ustat(sub[0], &statbuf) == 0) == testfor;
2281     break;
2282
2283     case ECOND_ISIP:
2284     case ECOND_ISIP4:
2285     case ECOND_ISIP6:
2286     rc = string_is_ip_address(sub[0], NULL);
2287     *yield = ((cond_type == ECOND_ISIP)? (rc != 0) :
2288              (cond_type == ECOND_ISIP4)? (rc == 4) : (rc == 6)) == testfor;
2289     break;
2290
2291     /* Various authentication tests - all optionally compiled */
2292
2293     case ECOND_PAM:
2294     #ifdef SUPPORT_PAM
2295     rc = auth_call_pam(sub[0], &expand_string_message);
2296     goto END_AUTH;
2297     #else
2298     goto COND_FAILED_NOT_COMPILED;
2299     #endif  /* SUPPORT_PAM */
2300
2301     case ECOND_RADIUS:
2302     #ifdef RADIUS_CONFIG_FILE
2303     rc = auth_call_radius(sub[0], &expand_string_message);
2304     goto END_AUTH;
2305     #else
2306     goto COND_FAILED_NOT_COMPILED;
2307     #endif  /* RADIUS_CONFIG_FILE */
2308
2309     case ECOND_LDAPAUTH:
2310     #ifdef LOOKUP_LDAP
2311       {
2312       /* Just to keep the interface the same */
2313       BOOL do_cache;
2314       int old_pool = store_pool;
2315       store_pool = POOL_SEARCH;
2316       rc = eldapauth_find((void *)(-1), NULL, sub[0], Ustrlen(sub[0]), NULL,
2317         &expand_string_message, &do_cache);
2318       store_pool = old_pool;
2319       }
2320     goto END_AUTH;
2321     #else
2322     goto COND_FAILED_NOT_COMPILED;
2323     #endif  /* LOOKUP_LDAP */
2324
2325     case ECOND_PWCHECK:
2326     #ifdef CYRUS_PWCHECK_SOCKET
2327     rc = auth_call_pwcheck(sub[0], &expand_string_message);
2328     goto END_AUTH;
2329     #else
2330     goto COND_FAILED_NOT_COMPILED;
2331     #endif  /* CYRUS_PWCHECK_SOCKET */
2332
2333     #if defined(SUPPORT_PAM) || defined(RADIUS_CONFIG_FILE) || \
2334         defined(LOOKUP_LDAP) || defined(CYRUS_PWCHECK_SOCKET)
2335     END_AUTH:
2336     if (rc == ERROR || rc == DEFER) return NULL;
2337     *yield = (rc == OK) == testfor;
2338     #endif
2339     }
2340   return s;
2341
2342
2343   /* call ACL (in a conditional context).  Accept true, deny false.
2344   Defer is a forced-fail.  Anything set by message= goes to $value.
2345   Up to ten parameters are used; we use the braces round the name+args
2346   like the saslauthd condition does, to permit a variable number of args.
2347   See also the expansion-item version EITEM_ACL and the traditional
2348   acl modifier ACLC_ACL.
2349   Since the ACL may allocate new global variables, tell our caller to not
2350   reclaim memory.
2351   */
2352
2353   case ECOND_ACL:
2354     /* ${if acl {{name}{arg1}{arg2}...}  {yes}{no}} */
2355     {
2356     uschar *sub[10];
2357     uschar *user_msg;
2358     BOOL cond = FALSE;
2359     int size = 0;
2360     int ptr = 0;
2361
2362     while (isspace(*s)) s++;
2363     if (*s++ != '{') goto COND_FAILED_CURLY_START;      /*}*/
2364
2365     switch(read_subs(sub, nelem(sub), 1,
2366       &s, yield == NULL, TRUE, US"acl", resetok))
2367       {
2368       case 1: expand_string_message = US"too few arguments or bracketing "
2369         "error for acl";
2370       case 2:
2371       case 3: return NULL;
2372       }
2373
2374     *resetok = FALSE;   /* eval_acl() might allocate; do not reclaim */
2375     if (yield != NULL) switch(eval_acl(sub, nelem(sub), &user_msg))
2376         {
2377         case OK:
2378           cond = TRUE;
2379         case FAIL:
2380           lookup_value = NULL;
2381           if (user_msg)
2382             {
2383             lookup_value = string_cat(NULL, &size, &ptr, user_msg);
2384             lookup_value[ptr] = '\0';
2385             }
2386           *yield = cond == testfor;
2387           break;
2388
2389         case DEFER:
2390           expand_string_forcedfail = TRUE;
2391           /*FALLTHROUGH*/
2392         default:
2393           expand_string_message = string_sprintf("error from acl \"%s\"", sub[0]);
2394           return NULL;
2395         }
2396     return s;
2397     }
2398
2399
2400   /* saslauthd: does Cyrus saslauthd authentication. Four parameters are used:
2401
2402      ${if saslauthd {{username}{password}{service}{realm}}  {yes}{no}}
2403
2404   However, the last two are optional. That is why the whole set is enclosed
2405   in their own set of braces. */
2406
2407   case ECOND_SASLAUTHD:
2408 #ifndef CYRUS_SASLAUTHD_SOCKET
2409     goto COND_FAILED_NOT_COMPILED;
2410 #else
2411     {
2412     uschar *sub[4];
2413     while (isspace(*s)) s++;
2414     if (*s++ != '{') goto COND_FAILED_CURLY_START;      /* }-for-text-editors */
2415     switch(read_subs(sub, nelem(sub), 2, &s, yield == NULL, TRUE, US"saslauthd",
2416                     resetok))
2417       {
2418       case 1: expand_string_message = US"too few arguments or bracketing "
2419         "error for saslauthd";
2420       case 2:
2421       case 3: return NULL;
2422       }
2423     if (sub[2] == NULL) sub[3] = NULL;  /* realm if no service */
2424     if (yield != NULL)
2425       {
2426       int rc = auth_call_saslauthd(sub[0], sub[1], sub[2], sub[3],
2427         &expand_string_message);
2428       if (rc == ERROR || rc == DEFER) return NULL;
2429       *yield = (rc == OK) == testfor;
2430       }
2431     return s;
2432     }
2433 #endif /* CYRUS_SASLAUTHD_SOCKET */
2434
2435
2436   /* symbolic operators for numeric and string comparison, and a number of
2437   other operators, all requiring two arguments.
2438
2439   crypteq:           encrypts plaintext and compares against an encrypted text,
2440                        using crypt(), crypt16(), MD5 or SHA-1
2441   inlist/inlisti:    checks if first argument is in the list of the second
2442   match:             does a regular expression match and sets up the numerical
2443                        variables if it succeeds
2444   match_address:     matches in an address list
2445   match_domain:      matches in a domain list
2446   match_ip:          matches a host list that is restricted to IP addresses
2447   match_local_part:  matches in a local part list
2448   */
2449
2450   case ECOND_MATCH_ADDRESS:
2451   case ECOND_MATCH_DOMAIN:
2452   case ECOND_MATCH_IP:
2453   case ECOND_MATCH_LOCAL_PART:
2454 #ifndef EXPAND_LISTMATCH_RHS
2455     sub2_honour_dollar = FALSE;
2456 #endif
2457     /* FALLTHROUGH */
2458
2459   case ECOND_CRYPTEQ:
2460   case ECOND_INLIST:
2461   case ECOND_INLISTI:
2462   case ECOND_MATCH:
2463
2464   case ECOND_NUM_L:     /* Numerical comparisons */
2465   case ECOND_NUM_LE:
2466   case ECOND_NUM_E:
2467   case ECOND_NUM_EE:
2468   case ECOND_NUM_G:
2469   case ECOND_NUM_GE:
2470
2471   case ECOND_STR_LT:    /* String comparisons */
2472   case ECOND_STR_LTI:
2473   case ECOND_STR_LE:
2474   case ECOND_STR_LEI:
2475   case ECOND_STR_EQ:
2476   case ECOND_STR_EQI:
2477   case ECOND_STR_GT:
2478   case ECOND_STR_GTI:
2479   case ECOND_STR_GE:
2480   case ECOND_STR_GEI:
2481
2482   for (i = 0; i < 2; i++)
2483     {
2484     /* Sometimes, we don't expand substrings; too many insecure configurations
2485     created using match_address{}{} and friends, where the second param
2486     includes information from untrustworthy sources. */
2487     BOOL honour_dollar = TRUE;
2488     if ((i > 0) && !sub2_honour_dollar)
2489       honour_dollar = FALSE;
2490
2491     while (isspace(*s)) s++;
2492     if (*s != '{')
2493       {
2494       if (i == 0) goto COND_FAILED_CURLY_START;
2495       expand_string_message = string_sprintf("missing 2nd string in {} "
2496         "after \"%s\"", name);
2497       return NULL;
2498       }
2499     sub[i] = expand_string_internal(s+1, TRUE, &s, yield == NULL,
2500         honour_dollar, resetok);
2501     if (sub[i] == NULL) return NULL;
2502     if (*s++ != '}') goto COND_FAILED_CURLY_END;
2503
2504     /* Convert to numerical if required; we know that the names of all the
2505     conditions that compare numbers do not start with a letter. This just saves
2506     checking for them individually. */
2507
2508     if (!isalpha(name[0]) && yield != NULL)
2509       if (sub[i][0] == 0)
2510         {
2511         num[i] = 0;
2512         DEBUG(D_expand)
2513           debug_printf("empty string cast to zero for numerical comparison\n");
2514         }
2515       else
2516         {
2517         num[i] = expanded_string_integer(sub[i], FALSE);
2518         if (expand_string_message != NULL) return NULL;
2519         }
2520     }
2521
2522   /* Result not required */
2523
2524   if (yield == NULL) return s;
2525
2526   /* Do an appropriate comparison */
2527
2528   switch(cond_type)
2529     {
2530     case ECOND_NUM_E:
2531     case ECOND_NUM_EE:
2532     tempcond = (num[0] == num[1]);
2533     break;
2534
2535     case ECOND_NUM_G:
2536     tempcond = (num[0] > num[1]);
2537     break;
2538
2539     case ECOND_NUM_GE:
2540     tempcond = (num[0] >= num[1]);
2541     break;
2542
2543     case ECOND_NUM_L:
2544     tempcond = (num[0] < num[1]);
2545     break;
2546
2547     case ECOND_NUM_LE:
2548     tempcond = (num[0] <= num[1]);
2549     break;
2550
2551     case ECOND_STR_LT:
2552     tempcond = (Ustrcmp(sub[0], sub[1]) < 0);
2553     break;
2554
2555     case ECOND_STR_LTI:
2556     tempcond = (strcmpic(sub[0], sub[1]) < 0);
2557     break;
2558
2559     case ECOND_STR_LE:
2560     tempcond = (Ustrcmp(sub[0], sub[1]) <= 0);
2561     break;
2562
2563     case ECOND_STR_LEI:
2564     tempcond = (strcmpic(sub[0], sub[1]) <= 0);
2565     break;
2566
2567     case ECOND_STR_EQ:
2568     tempcond = (Ustrcmp(sub[0], sub[1]) == 0);
2569     break;
2570
2571     case ECOND_STR_EQI:
2572     tempcond = (strcmpic(sub[0], sub[1]) == 0);
2573     break;
2574
2575     case ECOND_STR_GT:
2576     tempcond = (Ustrcmp(sub[0], sub[1]) > 0);
2577     break;
2578
2579     case ECOND_STR_GTI:
2580     tempcond = (strcmpic(sub[0], sub[1]) > 0);
2581     break;
2582
2583     case ECOND_STR_GE:
2584     tempcond = (Ustrcmp(sub[0], sub[1]) >= 0);
2585     break;
2586
2587     case ECOND_STR_GEI:
2588     tempcond = (strcmpic(sub[0], sub[1]) >= 0);
2589     break;
2590
2591     case ECOND_MATCH:   /* Regular expression match */
2592     re = pcre_compile(CS sub[1], PCRE_COPT, (const char **)&rerror, &roffset,
2593       NULL);
2594     if (re == NULL)
2595       {
2596       expand_string_message = string_sprintf("regular expression error in "
2597         "\"%s\": %s at offset %d", sub[1], rerror, roffset);
2598       return NULL;
2599       }
2600     tempcond = regex_match_and_setup(re, sub[0], 0, -1);
2601     break;
2602
2603     case ECOND_MATCH_ADDRESS:  /* Match in an address list */
2604     rc = match_address_list(sub[0], TRUE, FALSE, &(sub[1]), NULL, -1, 0, NULL);
2605     goto MATCHED_SOMETHING;
2606
2607     case ECOND_MATCH_DOMAIN:   /* Match in a domain list */
2608     rc = match_isinlist(sub[0], &(sub[1]), 0, &domainlist_anchor, NULL,
2609       MCL_DOMAIN + MCL_NOEXPAND, TRUE, NULL);
2610     goto MATCHED_SOMETHING;
2611
2612     case ECOND_MATCH_IP:       /* Match IP address in a host list */
2613     if (sub[0][0] != 0 && string_is_ip_address(sub[0], NULL) == 0)
2614       {
2615       expand_string_message = string_sprintf("\"%s\" is not an IP address",
2616         sub[0]);
2617       return NULL;
2618       }
2619     else
2620       {
2621       unsigned int *nullcache = NULL;
2622       check_host_block cb;
2623
2624       cb.host_name = US"";
2625       cb.host_address = sub[0];
2626
2627       /* If the host address starts off ::ffff: it is an IPv6 address in
2628       IPv4-compatible mode. Find the IPv4 part for checking against IPv4
2629       addresses. */
2630
2631       cb.host_ipv4 = (Ustrncmp(cb.host_address, "::ffff:", 7) == 0)?
2632         cb.host_address + 7 : cb.host_address;
2633
2634       rc = match_check_list(
2635              &sub[1],                   /* the list */
2636              0,                         /* separator character */
2637              &hostlist_anchor,          /* anchor pointer */
2638              &nullcache,                /* cache pointer */
2639              check_host,                /* function for testing */
2640              &cb,                       /* argument for function */
2641              MCL_HOST,                  /* type of check */
2642              sub[0],                    /* text for debugging */
2643              NULL);                     /* where to pass back data */
2644       }
2645     goto MATCHED_SOMETHING;
2646
2647     case ECOND_MATCH_LOCAL_PART:
2648     rc = match_isinlist(sub[0], &(sub[1]), 0, &localpartlist_anchor, NULL,
2649       MCL_LOCALPART + MCL_NOEXPAND, TRUE, NULL);
2650     /* Fall through */
2651     /* VVVVVVVVVVVV */
2652     MATCHED_SOMETHING:
2653     switch(rc)
2654       {
2655       case OK:
2656       tempcond = TRUE;
2657       break;
2658
2659       case FAIL:
2660       tempcond = FALSE;
2661       break;
2662
2663       case DEFER:
2664       expand_string_message = string_sprintf("unable to complete match "
2665         "against \"%s\": %s", sub[1], search_error_message);
2666       return NULL;
2667       }
2668
2669     break;
2670
2671     /* Various "encrypted" comparisons. If the second string starts with
2672     "{" then an encryption type is given. Default to crypt() or crypt16()
2673     (build-time choice). */
2674     /* }-for-text-editors */
2675
2676     case ECOND_CRYPTEQ:
2677     #ifndef SUPPORT_CRYPTEQ
2678     goto COND_FAILED_NOT_COMPILED;
2679     #else
2680     if (strncmpic(sub[1], US"{md5}", 5) == 0)
2681       {
2682       int sublen = Ustrlen(sub[1]+5);
2683       md5 base;
2684       uschar digest[16];
2685
2686       md5_start(&base);
2687       md5_end(&base, sub[0], Ustrlen(sub[0]), digest);
2688
2689       /* If the length that we are comparing against is 24, the MD5 digest
2690       is expressed as a base64 string. This is the way LDAP does it. However,
2691       some other software uses a straightforward hex representation. We assume
2692       this if the length is 32. Other lengths fail. */
2693
2694       if (sublen == 24)
2695         {
2696         uschar *coded = b64encode(digest, 16);
2697         DEBUG(D_auth) debug_printf("crypteq: using MD5+B64 hashing\n"
2698           "  subject=%s\n  crypted=%s\n", coded, sub[1]+5);
2699         tempcond = (Ustrcmp(coded, sub[1]+5) == 0);
2700         }
2701       else if (sublen == 32)
2702         {
2703         int i;
2704         uschar coded[36];
2705         for (i = 0; i < 16; i++) sprintf(CS (coded+2*i), "%02X", digest[i]);
2706         coded[32] = 0;
2707         DEBUG(D_auth) debug_printf("crypteq: using MD5+hex hashing\n"
2708           "  subject=%s\n  crypted=%s\n", coded, sub[1]+5);
2709         tempcond = (strcmpic(coded, sub[1]+5) == 0);
2710         }
2711       else
2712         {
2713         DEBUG(D_auth) debug_printf("crypteq: length for MD5 not 24 or 32: "
2714           "fail\n  crypted=%s\n", sub[1]+5);
2715         tempcond = FALSE;
2716         }
2717       }
2718
2719     else if (strncmpic(sub[1], US"{sha1}", 6) == 0)
2720       {
2721       int sublen = Ustrlen(sub[1]+6);
2722       hctx h;
2723       uschar digest[20];
2724
2725       sha1_start(&h);
2726       sha1_end(&h, sub[0], Ustrlen(sub[0]), digest);
2727
2728       /* If the length that we are comparing against is 28, assume the SHA1
2729       digest is expressed as a base64 string. If the length is 40, assume a
2730       straightforward hex representation. Other lengths fail. */
2731
2732       if (sublen == 28)
2733         {
2734         uschar *coded = b64encode(digest, 20);
2735         DEBUG(D_auth) debug_printf("crypteq: using SHA1+B64 hashing\n"
2736           "  subject=%s\n  crypted=%s\n", coded, sub[1]+6);
2737         tempcond = (Ustrcmp(coded, sub[1]+6) == 0);
2738         }
2739       else if (sublen == 40)
2740         {
2741         int i;
2742         uschar coded[44];
2743         for (i = 0; i < 20; i++) sprintf(CS (coded+2*i), "%02X", digest[i]);
2744         coded[40] = 0;
2745         DEBUG(D_auth) debug_printf("crypteq: using SHA1+hex hashing\n"
2746           "  subject=%s\n  crypted=%s\n", coded, sub[1]+6);
2747         tempcond = (strcmpic(coded, sub[1]+6) == 0);
2748         }
2749       else
2750         {
2751         DEBUG(D_auth) debug_printf("crypteq: length for SHA-1 not 28 or 40: "
2752           "fail\n  crypted=%s\n", sub[1]+6);
2753         tempcond = FALSE;
2754         }
2755       }
2756
2757     else   /* {crypt} or {crypt16} and non-{ at start */
2758            /* }-for-text-editors */
2759       {
2760       int which = 0;
2761       uschar *coded;
2762
2763       if (strncmpic(sub[1], US"{crypt}", 7) == 0)
2764         {
2765         sub[1] += 7;
2766         which = 1;
2767         }
2768       else if (strncmpic(sub[1], US"{crypt16}", 9) == 0)
2769         {
2770         sub[1] += 9;
2771         which = 2;
2772         }
2773       else if (sub[1][0] == '{')                /* }-for-text-editors */
2774         {
2775         expand_string_message = string_sprintf("unknown encryption mechanism "
2776           "in \"%s\"", sub[1]);
2777         return NULL;
2778         }
2779
2780       switch(which)
2781         {
2782         case 0:  coded = US DEFAULT_CRYPT(CS sub[0], CS sub[1]); break;
2783         case 1:  coded = US crypt(CS sub[0], CS sub[1]); break;
2784         default: coded = US crypt16(CS sub[0], CS sub[1]); break;
2785         }
2786
2787       #define STR(s) # s
2788       #define XSTR(s) STR(s)
2789       DEBUG(D_auth) debug_printf("crypteq: using %s()\n"
2790         "  subject=%s\n  crypted=%s\n",
2791         which == 0 ? XSTR(DEFAULT_CRYPT) : which == 1 ? "crypt" : "crypt16",
2792         coded, sub[1]);
2793       #undef STR
2794       #undef XSTR
2795
2796       /* If the encrypted string contains fewer than two characters (for the
2797       salt), force failure. Otherwise we get false positives: with an empty
2798       string the yield of crypt() is an empty string! */
2799
2800       if (coded)
2801         tempcond = Ustrlen(sub[1]) < 2 ? FALSE : Ustrcmp(coded, sub[1]) == 0;
2802       else if (errno == EINVAL)
2803         tempcond = FALSE;
2804       else
2805         {
2806         expand_string_message = string_sprintf("crypt error: %s\n",
2807           US strerror(errno));
2808         return NULL;
2809         }
2810       }
2811     break;
2812     #endif  /* SUPPORT_CRYPTEQ */
2813
2814     case ECOND_INLIST:
2815     case ECOND_INLISTI:
2816       {
2817       const uschar * list = sub[1];
2818       int sep = 0;
2819       uschar *save_iterate_item = iterate_item;
2820       int (*compare)(const uschar *, const uschar *);
2821
2822       DEBUG(D_expand) debug_printf("condition: %s\n", name);
2823
2824       tempcond = FALSE;
2825       compare = cond_type == ECOND_INLISTI
2826         ? strcmpic : (int (*)(const uschar *, const uschar *)) strcmp;
2827
2828       while ((iterate_item = string_nextinlist(&list, &sep, NULL, 0)))
2829         if (compare(sub[0], iterate_item) == 0)
2830           {
2831           tempcond = TRUE;
2832           break;
2833           }
2834       iterate_item = save_iterate_item;
2835       }
2836
2837     }   /* Switch for comparison conditions */
2838
2839   *yield = tempcond == testfor;
2840   return s;    /* End of comparison conditions */
2841
2842
2843   /* and/or: computes logical and/or of several conditions */
2844
2845   case ECOND_AND:
2846   case ECOND_OR:
2847   subcondptr = (yield == NULL)? NULL : &tempcond;
2848   combined_cond = (cond_type == ECOND_AND);
2849
2850   while (isspace(*s)) s++;
2851   if (*s++ != '{') goto COND_FAILED_CURLY_START;        /* }-for-text-editors */
2852
2853   for (;;)
2854     {
2855     while (isspace(*s)) s++;
2856     /* {-for-text-editors */
2857     if (*s == '}') break;
2858     if (*s != '{')                                      /* }-for-text-editors */
2859       {
2860       expand_string_message = string_sprintf("each subcondition "
2861         "inside an \"%s{...}\" condition must be in its own {}", name);
2862       return NULL;
2863       }
2864
2865     if (!(s = eval_condition(s+1, resetok, subcondptr)))
2866       {
2867       expand_string_message = string_sprintf("%s inside \"%s{...}\" condition",
2868         expand_string_message, name);
2869       return NULL;
2870       }
2871     while (isspace(*s)) s++;
2872
2873     /* {-for-text-editors */
2874     if (*s++ != '}')
2875       {
2876       /* {-for-text-editors */
2877       expand_string_message = string_sprintf("missing } at end of condition "
2878         "inside \"%s\" group", name);
2879       return NULL;
2880       }
2881
2882     if (yield != NULL)
2883       {
2884       if (cond_type == ECOND_AND)
2885         {
2886         combined_cond &= tempcond;
2887         if (!combined_cond) subcondptr = NULL;  /* once false, don't */
2888         }                                       /* evaluate any more */
2889       else
2890         {
2891         combined_cond |= tempcond;
2892         if (combined_cond) subcondptr = NULL;   /* once true, don't */
2893         }                                       /* evaluate any more */
2894       }
2895     }
2896
2897   if (yield != NULL) *yield = (combined_cond == testfor);
2898   return ++s;
2899
2900
2901   /* forall/forany: iterates a condition with different values */
2902
2903   case ECOND_FORALL:
2904   case ECOND_FORANY:
2905     {
2906     const uschar * list;
2907     int sep = 0;
2908     uschar *save_iterate_item = iterate_item;
2909
2910     DEBUG(D_expand) debug_printf("condition: %s\n", name);
2911
2912     while (isspace(*s)) s++;
2913     if (*s++ != '{') goto COND_FAILED_CURLY_START;      /* }-for-text-editors */
2914     sub[0] = expand_string_internal(s, TRUE, &s, (yield == NULL), TRUE, resetok);
2915     if (sub[0] == NULL) return NULL;
2916     /* {-for-text-editors */
2917     if (*s++ != '}') goto COND_FAILED_CURLY_END;
2918
2919     while (isspace(*s)) s++;
2920     if (*s++ != '{') goto COND_FAILED_CURLY_START;      /* }-for-text-editors */
2921
2922     sub[1] = s;
2923
2924     /* Call eval_condition once, with result discarded (as if scanning a
2925     "false" part). This allows us to find the end of the condition, because if
2926     the list it empty, we won't actually evaluate the condition for real. */
2927
2928     if (!(s = eval_condition(sub[1], resetok, NULL)))
2929       {
2930       expand_string_message = string_sprintf("%s inside \"%s\" condition",
2931         expand_string_message, name);
2932       return NULL;
2933       }
2934     while (isspace(*s)) s++;
2935
2936     /* {-for-text-editors */
2937     if (*s++ != '}')
2938       {
2939       /* {-for-text-editors */
2940       expand_string_message = string_sprintf("missing } at end of condition "
2941         "inside \"%s\"", name);
2942       return NULL;
2943       }
2944
2945     if (yield != NULL) *yield = !testfor;
2946     list = sub[0];
2947     while ((iterate_item = string_nextinlist(&list, &sep, NULL, 0)) != NULL)
2948       {
2949       DEBUG(D_expand) debug_printf("%s: $item = \"%s\"\n", name, iterate_item);
2950       if (!eval_condition(sub[1], resetok, &tempcond))
2951         {
2952         expand_string_message = string_sprintf("%s inside \"%s\" condition",
2953           expand_string_message, name);
2954         iterate_item = save_iterate_item;
2955         return NULL;
2956         }
2957       DEBUG(D_expand) debug_printf("%s: condition evaluated to %s\n", name,
2958         tempcond? "true":"false");
2959
2960       if (yield != NULL) *yield = (tempcond == testfor);
2961       if (tempcond == (cond_type == ECOND_FORANY)) break;
2962       }
2963
2964     iterate_item = save_iterate_item;
2965     return s;
2966     }
2967
2968
2969   /* The bool{} expansion condition maps a string to boolean.
2970   The values supported should match those supported by the ACL condition
2971   (acl.c, ACLC_CONDITION) so that we keep to a minimum the different ideas
2972   of true/false.  Note that Router "condition" rules have a different
2973   interpretation, where general data can be used and only a few values
2974   map to FALSE.
2975   Note that readconf.c boolean matching, for boolean configuration options,
2976   only matches true/yes/false/no.
2977   The bool_lax{} condition matches the Router logic, which is much more
2978   liberal. */
2979   case ECOND_BOOL:
2980   case ECOND_BOOL_LAX:
2981     {
2982     uschar *sub_arg[1];
2983     uschar *t, *t2;
2984     uschar *ourname;
2985     size_t len;
2986     BOOL boolvalue = FALSE;
2987     while (isspace(*s)) s++;
2988     if (*s != '{') goto COND_FAILED_CURLY_START;        /* }-for-text-editors */
2989     ourname = cond_type == ECOND_BOOL_LAX ? US"bool_lax" : US"bool";
2990     switch(read_subs(sub_arg, 1, 1, &s, yield == NULL, FALSE, ourname, resetok))
2991       {
2992       case 1: expand_string_message = string_sprintf(
2993                   "too few arguments or bracketing error for %s",
2994                   ourname);
2995       /*FALLTHROUGH*/
2996       case 2:
2997       case 3: return NULL;
2998       }
2999     t = sub_arg[0];
3000     while (isspace(*t)) t++;
3001     len = Ustrlen(t);
3002     if (len)
3003       {
3004       /* trailing whitespace: seems like a good idea to ignore it too */
3005       t2 = t + len - 1;
3006       while (isspace(*t2)) t2--;
3007       if (t2 != (t + len))
3008         {
3009         *++t2 = '\0';
3010         len = t2 - t;
3011         }
3012       }
3013     DEBUG(D_expand)
3014       debug_printf("considering %s: %s\n", ourname, len ? t : US"<empty>");
3015     /* logic for the lax case from expand_check_condition(), which also does
3016     expands, and the logic is both short and stable enough that there should
3017     be no maintenance burden from replicating it. */
3018     if (len == 0)
3019       boolvalue = FALSE;
3020     else if (*t == '-'
3021              ? Ustrspn(t+1, "0123456789") == len-1
3022              : Ustrspn(t,   "0123456789") == len)
3023       {
3024       boolvalue = (Uatoi(t) == 0) ? FALSE : TRUE;
3025       /* expand_check_condition only does a literal string "0" check */
3026       if ((cond_type == ECOND_BOOL_LAX) && (len > 1))
3027         boolvalue = TRUE;
3028       }
3029     else if (strcmpic(t, US"true") == 0 || strcmpic(t, US"yes") == 0)
3030       boolvalue = TRUE;
3031     else if (strcmpic(t, US"false") == 0 || strcmpic(t, US"no") == 0)
3032       boolvalue = FALSE;
3033     else if (cond_type == ECOND_BOOL_LAX)
3034       boolvalue = TRUE;
3035     else
3036       {
3037       expand_string_message = string_sprintf("unrecognised boolean "
3038        "value \"%s\"", t);
3039       return NULL;
3040       }
3041     if (yield != NULL) *yield = (boolvalue == testfor);
3042     return s;
3043     }
3044
3045   /* Unknown condition */
3046
3047   default:
3048   expand_string_message = string_sprintf("unknown condition \"%s\"", name);
3049   return NULL;
3050   }   /* End switch on condition type */
3051
3052 /* Missing braces at start and end of data */
3053
3054 COND_FAILED_CURLY_START:
3055 expand_string_message = string_sprintf("missing { after \"%s\"", name);
3056 return NULL;
3057
3058 COND_FAILED_CURLY_END:
3059 expand_string_message = string_sprintf("missing } at end of \"%s\" condition",
3060   name);
3061 return NULL;
3062
3063 /* A condition requires code that is not compiled */
3064
3065 #if !defined(SUPPORT_PAM) || !defined(RADIUS_CONFIG_FILE) || \
3066     !defined(LOOKUP_LDAP) || !defined(CYRUS_PWCHECK_SOCKET) || \
3067     !defined(SUPPORT_CRYPTEQ) || !defined(CYRUS_SASLAUTHD_SOCKET)
3068 COND_FAILED_NOT_COMPILED:
3069 expand_string_message = string_sprintf("support for \"%s\" not compiled",
3070   name);
3071 return NULL;
3072 #endif
3073 }
3074
3075
3076
3077
3078 /*************************************************
3079 *          Save numerical variables              *
3080 *************************************************/
3081
3082 /* This function is called from items such as "if" that want to preserve and
3083 restore the numbered variables.
3084
3085 Arguments:
3086   save_expand_string    points to an array of pointers to set
3087   save_expand_nlength   points to an array of ints for the lengths
3088
3089 Returns:                the value of expand max to save
3090 */
3091
3092 static int
3093 save_expand_strings(uschar **save_expand_nstring, int *save_expand_nlength)
3094 {
3095 int i;
3096 for (i = 0; i <= expand_nmax; i++)
3097   {
3098   save_expand_nstring[i] = expand_nstring[i];
3099   save_expand_nlength[i] = expand_nlength[i];
3100   }
3101 return expand_nmax;
3102 }
3103
3104
3105
3106 /*************************************************
3107 *           Restore numerical variables          *
3108 *************************************************/
3109
3110 /* This function restored saved values of numerical strings.
3111
3112 Arguments:
3113   save_expand_nmax      the number of strings to restore
3114   save_expand_string    points to an array of pointers
3115   save_expand_nlength   points to an array of ints
3116
3117 Returns:                nothing
3118 */
3119
3120 static void
3121 restore_expand_strings(int save_expand_nmax, uschar **save_expand_nstring,
3122   int *save_expand_nlength)
3123 {
3124 int i;
3125 expand_nmax = save_expand_nmax;
3126 for (i = 0; i <= expand_nmax; i++)
3127   {
3128   expand_nstring[i] = save_expand_nstring[i];
3129   expand_nlength[i] = save_expand_nlength[i];
3130   }
3131 }
3132
3133
3134
3135
3136
3137 /*************************************************
3138 *            Handle yes/no substrings            *
3139 *************************************************/
3140
3141 /* This function is used by ${if}, ${lookup} and ${extract} to handle the
3142 alternative substrings that depend on whether or not the condition was true,
3143 or the lookup or extraction succeeded. The substrings always have to be
3144 expanded, to check their syntax, but "skipping" is set when the result is not
3145 needed - this avoids unnecessary nested lookups.
3146
3147 Arguments:
3148   skipping       TRUE if we were skipping when this item was reached
3149   yes            TRUE if the first string is to be used, else use the second
3150   save_lookup    a value to put back into lookup_value before the 2nd expansion
3151   sptr           points to the input string pointer
3152   yieldptr       points to the output string pointer
3153   sizeptr        points to the output string size
3154   ptrptr         points to the output string pointer
3155   type           "lookup", "if", "extract", "run", "env", "listextract" or
3156                  "certextract" for error message
3157   resetok        if not NULL, pointer to flag - write FALSE if unsafe to reset
3158                 the store.
3159
3160 Returns:         0 OK; lookup_value has been reset to save_lookup
3161                  1 expansion failed
3162                  2 expansion failed because of bracketing error
3163 */
3164
3165 static int
3166 process_yesno(BOOL skipping, BOOL yes, uschar *save_lookup, const uschar **sptr,
3167   uschar **yieldptr, int *sizeptr, int *ptrptr, uschar *type, BOOL *resetok)
3168 {
3169 int rc = 0;
3170 const uschar *s = *sptr;    /* Local value */
3171 uschar *sub1, *sub2;
3172 const uschar * errwhere;
3173
3174 /* If there are no following strings, we substitute the contents of $value for
3175 lookups and for extractions in the success case. For the ${if item, the string
3176 "true" is substituted. In the fail case, nothing is substituted for all three
3177 items. */
3178
3179 while (isspace(*s)) s++;
3180 if (*s == '}')
3181   {
3182   if (type[0] == 'i')
3183     {
3184     if (yes) *yieldptr = string_catn(*yieldptr, sizeptr, ptrptr, US"true", 4);
3185     }
3186   else
3187     {
3188     if (yes && lookup_value)
3189       *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, lookup_value);
3190     lookup_value = save_lookup;
3191     }
3192   s++;
3193   goto RETURN;
3194   }
3195
3196 /* The first following string must be braced. */
3197
3198 if (*s++ != '{')
3199   {
3200   errwhere = US"'yes' part did not start with '{'";
3201   goto FAILED_CURLY;
3202   }
3203
3204 /* Expand the first substring. Forced failures are noticed only if we actually
3205 want this string. Set skipping in the call in the fail case (this will always
3206 be the case if we were already skipping). */
3207
3208 sub1 = expand_string_internal(s, TRUE, &s, !yes, TRUE, resetok);
3209 if (sub1 == NULL && (yes || !expand_string_forcedfail)) goto FAILED;
3210 expand_string_forcedfail = FALSE;
3211 if (*s++ != '}')
3212   {
3213   errwhere = US"'yes' part did not end with '}'";
3214   goto FAILED_CURLY;
3215   }
3216
3217 /* If we want the first string, add it to the output */
3218
3219 if (yes)
3220   *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, sub1);
3221
3222 /* If this is called from a lookup/env or a (cert)extract, we want to restore
3223 $value to what it was at the start of the item, so that it has this value
3224 during the second string expansion. For the call from "if" or "run" to this
3225 function, save_lookup is set to lookup_value, so that this statement does
3226 nothing. */
3227
3228 lookup_value = save_lookup;
3229
3230 /* There now follows either another substring, or "fail", or nothing. This
3231 time, forced failures are noticed only if we want the second string. We must
3232 set skipping in the nested call if we don't want this string, or if we were
3233 already skipping. */
3234
3235 while (isspace(*s)) s++;
3236 if (*s == '{')
3237   {
3238   sub2 = expand_string_internal(s+1, TRUE, &s, yes || skipping, TRUE, resetok);
3239   if (sub2 == NULL && (!yes || !expand_string_forcedfail)) goto FAILED;
3240   expand_string_forcedfail = FALSE;
3241   if (*s++ != '}')
3242     {
3243     errwhere = US"'no' part did not start with '{'";
3244     goto FAILED_CURLY;
3245     }
3246
3247   /* If we want the second string, add it to the output */
3248
3249   if (!yes)
3250     *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, sub2);
3251   }
3252
3253 /* If there is no second string, but the word "fail" is present when the use of
3254 the second string is wanted, set a flag indicating it was a forced failure
3255 rather than a syntactic error. Swallow the terminating } in case this is nested
3256 inside another lookup or if or extract. */
3257
3258 else if (*s != '}')
3259   {
3260   uschar name[256];
3261   /* deconst cast ok here as source is s anyway */
3262   s = US read_name(name, sizeof(name), s, US"_");
3263   if (Ustrcmp(name, "fail") == 0)
3264     {
3265     if (!yes && !skipping)
3266       {
3267       while (isspace(*s)) s++;
3268       if (*s++ != '}')
3269         {
3270         errwhere = US"did not close with '}' after forcedfail";
3271         goto FAILED_CURLY;
3272         }
3273       expand_string_message =
3274         string_sprintf("\"%s\" failed and \"fail\" requested", type);
3275       expand_string_forcedfail = TRUE;
3276       goto FAILED;
3277       }
3278     }
3279   else
3280     {
3281     expand_string_message =
3282       string_sprintf("syntax error in \"%s\" item - \"fail\" expected", type);
3283     goto FAILED;
3284     }
3285   }
3286
3287 /* All we have to do now is to check on the final closing brace. */
3288
3289 while (isspace(*s)) s++;
3290 if (*s++ != '}')
3291   {
3292   errwhere = US"did not close with '}'";
3293   goto FAILED_CURLY;
3294   }
3295
3296
3297 RETURN:
3298 /* Update the input pointer value before returning */
3299 *sptr = s;
3300 return rc;
3301
3302 FAILED_CURLY:
3303   /* Get here if there is a bracketing failure */
3304   expand_string_message = string_sprintf(
3305     "curly-bracket problem in conditional yes/no parsing: %s\n"
3306     " remaining string is '%s'", errwhere, --s);
3307   rc = 2;
3308   goto RETURN;
3309
3310 FAILED:
3311   /* Get here for other failures */
3312   rc = 1;
3313   goto RETURN;
3314 }
3315
3316
3317
3318
3319 /*************************************************
3320 *    Handle MD5 or SHA-1 computation for HMAC    *
3321 *************************************************/
3322
3323 /* These are some wrapping functions that enable the HMAC code to be a bit
3324 cleaner. A good compiler will spot the tail recursion.
3325
3326 Arguments:
3327   type         HMAC_MD5 or HMAC_SHA1
3328   remaining    are as for the cryptographic hash functions
3329
3330 Returns:       nothing
3331 */
3332
3333 static void
3334 chash_start(int type, void *base)
3335 {
3336 if (type == HMAC_MD5)
3337   md5_start((md5 *)base);
3338 else
3339   sha1_start((hctx *)base);
3340 }
3341
3342 static void
3343 chash_mid(int type, void *base, uschar *string)
3344 {
3345 if (type == HMAC_MD5)
3346   md5_mid((md5 *)base, string);
3347 else
3348   sha1_mid((hctx *)base, string);
3349 }
3350
3351 static void
3352 chash_end(int type, void *base, uschar *string, int length, uschar *digest)
3353 {
3354 if (type == HMAC_MD5)
3355   md5_end((md5 *)base, string, length, digest);
3356 else
3357   sha1_end((hctx *)base, string, length, digest);
3358 }
3359
3360
3361