src/src/expand.c

   1 /*************************************************
   2 *     Exim - an Internet mail transport agent    *
   3 *************************************************/
   4
   5 /* Copyright (c) University of Cambridge 1995 - 2015 */
   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 EXPERIMENTAL_INTERNATIONAL
 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 EXPERIMENTAL_INTERNATIONAL
 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 EXPERIMENTAL_INTERNATIONAL
 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 EXPERIMENTAL_INTERNATIONAL
 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"domain",
 205   US"escape",
 206   US"eval",
 207   US"eval10",
 208   US"expand",
 209   US"h",
 210   US"hash",
 211   US"hex2b64",
 212   US"hexquote",
 213   US"ipv6denorm",
 214   US"ipv6norm",
 215   US"l",
 216   US"lc",
 217   US"length",
 218   US"listcount",
 219   US"listnamed",
 220   US"mask",
 221   US"md5",
 222   US"nh",
 223   US"nhash",
 224   US"quote",
 225   US"randint",
 226   US"rfc2047",
 227   US"rfc2047d",
 228   US"rxquote",
 229   US"s",
 230   US"sha1",
 231   US"sha256",
 232   US"stat",
 233   US"str2b64",
 234   US"strlen",
 235   US"substr",
 236   US"uc",
 237   US"utf8clean" };
 238
 239 enum {
 240   EOP_ADDRESS =  nelem(op_table_underscore),
 241   EOP_ADDRESSES,
 242   EOP_BASE62,
 243   EOP_BASE62D,
 244   EOP_DOMAIN,
 245   EOP_ESCAPE,
 246   EOP_EVAL,
 247   EOP_EVAL10,
 248   EOP_EXPAND,
 249   EOP_H,
 250   EOP_HASH,
 251   EOP_HEX2B64,
 252   EOP_HEXQUOTE,
 253   EOP_IPV6DENORM,
 254   EOP_IPV6NORM,
 255   EOP_L,
 256   EOP_LC,
 257   EOP_LENGTH,
 258   EOP_LISTCOUNT,
 259   EOP_LISTNAMED,
 260   EOP_MASK,
 261   EOP_MD5,
 262   EOP_NH,
 263   EOP_NHASH,
 264   EOP_QUOTE,
 265   EOP_RANDINT,
 266   EOP_RFC2047,
 267   EOP_RFC2047D,
 268   EOP_RXQUOTE,
 269   EOP_S,
 270   EOP_SHA1,
 271   EOP_SHA256,
 272   EOP_STAT,
 273   EOP_STR2B64,
 274   EOP_STRLEN,
 275   EOP_SUBSTR,
 276   EOP_UC,
 277   EOP_UTF8CLEAN };
 278
 279
 280 /* Table of condition names, and corresponding switch numbers. The names must
 281 be in alphabetical order. */
 282
 283 static uschar *cond_table[] = {
 284   US"<",
 285   US"<=",
 286   US"=",
 287   US"==",     /* Backward compatibility */
 288   US">",
 289   US">=",
 290   US"acl",
 291   US"and",
 292   US"bool",
 293   US"bool_lax",
 294   US"crypteq",
 295   US"def",
 296   US"eq",
 297   US"eqi",
 298   US"exists",
 299   US"first_delivery",
 300   US"forall",
 301   US"forany",
 302   US"ge",
 303   US"gei",
 304   US"gt",
 305   US"gti",
 306   US"inlist",
 307   US"inlisti",
 308   US"isip",
 309   US"isip4",
 310   US"isip6",
 311   US"ldapauth",
 312   US"le",
 313   US"lei",
 314   US"lt",
 315   US"lti",
 316   US"match",
 317   US"match_address",
 318   US"match_domain",
 319   US"match_ip",
 320   US"match_local_part",
 321   US"or",
 322   US"pam",
 323   US"pwcheck",
 324   US"queue_running",
 325   US"radius",
 326   US"saslauthd"
 327 };
 328
 329 enum {
 330   ECOND_NUM_L,
 331   ECOND_NUM_LE,
 332   ECOND_NUM_E,
 333   ECOND_NUM_EE,
 334   ECOND_NUM_G,
 335   ECOND_NUM_GE,
 336   ECOND_ACL,
 337   ECOND_AND,
 338   ECOND_BOOL,
 339   ECOND_BOOL_LAX,
 340   ECOND_CRYPTEQ,
 341   ECOND_DEF,
 342   ECOND_STR_EQ,
 343   ECOND_STR_EQI,
 344   ECOND_EXISTS,
 345   ECOND_FIRST_DELIVERY,
 346   ECOND_FORALL,
 347   ECOND_FORANY,
 348   ECOND_STR_GE,
 349   ECOND_STR_GEI,
 350   ECOND_STR_GT,
 351   ECOND_STR_GTI,
 352   ECOND_INLIST,
 353   ECOND_INLISTI,
 354   ECOND_ISIP,
 355   ECOND_ISIP4,
 356   ECOND_ISIP6,
 357   ECOND_LDAPAUTH,
 358   ECOND_STR_LE,
 359   ECOND_STR_LEI,
 360   ECOND_STR_LT,
 361   ECOND_STR_LTI,
 362   ECOND_MATCH,
 363   ECOND_MATCH_ADDRESS,
 364   ECOND_MATCH_DOMAIN,
 365   ECOND_MATCH_IP,
 366   ECOND_MATCH_LOCAL_PART,
 367   ECOND_OR,
 368   ECOND_PAM,
 369   ECOND_PWCHECK,
 370   ECOND_QUEUE_RUNNING,
 371   ECOND_RADIUS,
 372   ECOND_SASLAUTHD
 373 };
 374
 375
 376 /* Types of table entry */
 377
 378 enum vtypes {
 379   vtype_int,            /* value is address of int */
 380   vtype_filter_int,     /* ditto, but recognized only when filtering */
 381   vtype_ino,            /* value is address of ino_t (not always an int) */
 382   vtype_uid,            /* value is address of uid_t (not always an int) */
 383   vtype_gid,            /* value is address of gid_t (not always an int) */
 384   vtype_bool,           /* value is address of bool */
 385   vtype_stringptr,      /* value is address of pointer to string */
 386   vtype_msgbody,        /* as stringptr, but read when first required */
 387   vtype_msgbody_end,    /* ditto, the end of the message */
 388   vtype_msgheaders,     /* the message's headers, processed */
 389   vtype_msgheaders_raw, /* the message's headers, unprocessed */
 390   vtype_localpart,      /* extract local part from string */
 391   vtype_domain,         /* extract domain from string */
 392   vtype_string_func,    /* value is string returned by given function */
 393   vtype_todbsdin,       /* value not used; generate BSD inbox tod */
 394   vtype_tode,           /* value not used; generate tod in epoch format */
 395   vtype_todel,          /* value not used; generate tod in epoch/usec format */
 396   vtype_todf,           /* value not used; generate full tod */
 397   vtype_todl,           /* value not used; generate log tod */
 398   vtype_todlf,          /* value not used; generate log file datestamp tod */
 399   vtype_todzone,        /* value not used; generate time zone only */
 400   vtype_todzulu,        /* value not used; generate zulu tod */
 401   vtype_reply,          /* value not used; get reply from headers */
 402   vtype_pid,            /* value not used; result is pid */
 403   vtype_host_lookup,    /* value not used; get host name */
 404   vtype_load_avg,       /* value not used; result is int from os_getloadavg */
 405   vtype_pspace,         /* partition space; value is T/F for spool/log */
 406   vtype_pinodes,        /* partition inodes; value is T/F for spool/log */
 407   vtype_cert            /* SSL certificate */
 408   #ifndef DISABLE_DKIM
 409   ,vtype_dkim           /* Lookup of value in DKIM signature */
 410   #endif
 411 };
 412
 413 /* Type for main variable table */
 414
 415 typedef struct {
 416   const char *name;
 417   enum vtypes type;
 418   void       *value;
 419 } var_entry;
 420
 421 /* Type for entries pointing to address/length pairs. Not currently
 422 in use. */
 423
 424 typedef struct {
 425   uschar **address;
 426   int  *length;
 427 } alblock;
 428
 429 static uschar * fn_recipients(void);
 430
 431 /* This table must be kept in alphabetical order. */
 432
 433 static var_entry var_table[] = {
 434   /* WARNING: Do not invent variables whose names start acl_c or acl_m because
 435      they will be confused with user-creatable ACL variables. */
 436   { "acl_arg1",            vtype_stringptr,   &acl_arg[0] },
 437   { "acl_arg2",            vtype_stringptr,   &acl_arg[1] },
 438   { "acl_arg3",            vtype_stringptr,   &acl_arg[2] },
 439   { "acl_arg4",            vtype_stringptr,   &acl_arg[3] },
 440   { "acl_arg5",            vtype_stringptr,   &acl_arg[4] },
 441   { "acl_arg6",            vtype_stringptr,   &acl_arg[5] },
 442   { "acl_arg7",            vtype_stringptr,   &acl_arg[6] },
 443   { "acl_arg8",            vtype_stringptr,   &acl_arg[7] },
 444   { "acl_arg9",            vtype_stringptr,   &acl_arg[8] },
 445   { "acl_narg",            vtype_int,         &acl_narg },
 446   { "acl_verify_message",  vtype_stringptr,   &acl_verify_message },
 447   { "address_data",        vtype_stringptr,   &deliver_address_data },
 448   { "address_file",        vtype_stringptr,   &address_file },
 449   { "address_pipe",        vtype_stringptr,   &address_pipe },
 450   { "authenticated_fail_id",vtype_stringptr,  &authenticated_fail_id },
 451   { "authenticated_id",    vtype_stringptr,   &authenticated_id },
 452   { "authenticated_sender",vtype_stringptr,   &authenticated_sender },
 453   { "authentication_failed",vtype_int,        &authentication_failed },
 454 #ifdef WITH_CONTENT_SCAN
 455   { "av_failed",           vtype_int,         &av_failed },
 456 #endif
 457 #ifdef EXPERIMENTAL_BRIGHTMAIL
 458   { "bmi_alt_location",    vtype_stringptr,   &bmi_alt_location },
 459   { "bmi_base64_tracker_verdict", vtype_stringptr, &bmi_base64_tracker_verdict },
 460   { "bmi_base64_verdict",  vtype_stringptr,   &bmi_base64_verdict },
 461   { "bmi_deliver",         vtype_int,         &bmi_deliver },
 462 #endif
 463   { "body_linecount",      vtype_int,         &body_linecount },
 464   { "body_zerocount",      vtype_int,         &body_zerocount },
 465   { "bounce_recipient",    vtype_stringptr,   &bounce_recipient },
 466   { "bounce_return_size_limit", vtype_int,    &bounce_return_size_limit },
 467   { "caller_gid",          vtype_gid,         &real_gid },
 468   { "caller_uid",          vtype_uid,         &real_uid },
 469   { "callout_address",     vtype_stringptr,   &callout_address },
 470   { "compile_date",        vtype_stringptr,   &version_date },
 471   { "compile_number",      vtype_stringptr,   &version_cnumber },
 472   { "config_dir",          vtype_stringptr,   &config_main_directory },
 473   { "config_file",         vtype_stringptr,   &config_main_filename },
 474   { "csa_status",          vtype_stringptr,   &csa_status },
 475 #ifdef EXPERIMENTAL_DCC
 476   { "dcc_header",          vtype_stringptr,   &dcc_header },
 477   { "dcc_result",          vtype_stringptr,   &dcc_result },
 478 #endif
 479 #ifdef WITH_OLD_DEMIME
 480   { "demime_errorlevel",   vtype_int,         &demime_errorlevel },
 481   { "demime_reason",       vtype_stringptr,   &demime_reason },
 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_nosubdomains",vtype_dkim,       (void *)DKIM_NOSUBDOMAINS },
 497   { "dkim_key_notes",      vtype_dkim,        (void *)DKIM_KEY_NOTES },
 498   { "dkim_key_srvtype",    vtype_dkim,        (void *)DKIM_KEY_SRVTYPE },
 499   { "dkim_key_testing",    vtype_dkim,        (void *)DKIM_KEY_TESTING },
 500   { "dkim_selector",       vtype_stringptr,   &dkim_signing_selector },
 501   { "dkim_signers",        vtype_stringptr,   &dkim_signers },
 502   { "dkim_verify_reason",  vtype_dkim,        (void *)DKIM_VERIFY_REASON },
 503   { "dkim_verify_status",  vtype_dkim,        (void *)DKIM_VERIFY_STATUS},
 504 #endif
 505 #ifdef EXPERIMENTAL_DMARC
 506   { "dmarc_ar_header",     vtype_stringptr,   &dmarc_ar_header },
 507   { "dmarc_domain_policy", vtype_stringptr,   &dmarc_domain_policy },
 508   { "dmarc_status",        vtype_stringptr,   &dmarc_status },
 509   { "dmarc_status_text",   vtype_stringptr,   &dmarc_status_text },
 510   { "dmarc_used_domain",   vtype_stringptr,   &dmarc_used_domain },
 511 #endif
 512   { "dnslist_domain",      vtype_stringptr,   &dnslist_domain },
 513   { "dnslist_matched",     vtype_stringptr,   &dnslist_matched },
 514   { "dnslist_text",        vtype_stringptr,   &dnslist_text },
 515   { "dnslist_value",       vtype_stringptr,   &dnslist_value },
 516   { "domain",              vtype_stringptr,   &deliver_domain },
 517   { "domain_data",         vtype_stringptr,   &deliver_domain_data },
 518 #ifdef EXPERIMENTAL_EVENT
 519   { "event_data",          vtype_stringptr,   &event_data },
 520
 521   /*XXX want to use generic vars for as many of these as possible*/
 522   { "event_defer_errno",   vtype_int,         &event_defer_errno },
 523
 524   { "event_name",          vtype_stringptr,   &event_name },
 525 #endif
 526   { "exim_gid",            vtype_gid,         &exim_gid },
 527   { "exim_path",           vtype_stringptr,   &exim_path },
 528   { "exim_uid",            vtype_uid,         &exim_uid },
 529   { "exim_version",        vtype_stringptr,   &version_string },
 530 #ifdef WITH_OLD_DEMIME
 531   { "found_extension",     vtype_stringptr,   &found_extension },
 532 #endif
 533   { "headers_added",       vtype_string_func, &fn_hdrs_added },
 534   { "home",                vtype_stringptr,   &deliver_home },
 535   { "host",                vtype_stringptr,   &deliver_host },
 536   { "host_address",        vtype_stringptr,   &deliver_host_address },
 537   { "host_data",           vtype_stringptr,   &host_data },
 538   { "host_lookup_deferred",vtype_int,         &host_lookup_deferred },
 539   { "host_lookup_failed",  vtype_int,         &host_lookup_failed },
 540   { "host_port",           vtype_int,         &deliver_host_port },
 541   { "inode",               vtype_ino,         &deliver_inode },
 542   { "interface_address",   vtype_stringptr,   &interface_address },
 543   { "interface_port",      vtype_int,         &interface_port },
 544   { "item",                vtype_stringptr,   &iterate_item },
 545   #ifdef LOOKUP_LDAP
 546   { "ldap_dn",             vtype_stringptr,   &eldap_dn },
 547   #endif
 548   { "load_average",        vtype_load_avg,    NULL },
 549   { "local_part",          vtype_stringptr,   &deliver_localpart },
 550   { "local_part_data",     vtype_stringptr,   &deliver_localpart_data },
 551   { "local_part_prefix",   vtype_stringptr,   &deliver_localpart_prefix },
 552   { "local_part_suffix",   vtype_stringptr,   &deliver_localpart_suffix },
 553   { "local_scan_data",     vtype_stringptr,   &local_scan_data },
 554   { "local_user_gid",      vtype_gid,         &local_user_gid },
 555   { "local_user_uid",      vtype_uid,         &local_user_uid },
 556   { "localhost_number",    vtype_int,         &host_number },
 557   { "log_inodes",          vtype_pinodes,     (void *)FALSE },
 558   { "log_space",           vtype_pspace,      (void *)FALSE },
 559   { "lookup_dnssec_authenticated",vtype_stringptr,&lookup_dnssec_authenticated},
 560   { "mailstore_basename",  vtype_stringptr,   &mailstore_basename },
 561 #ifdef WITH_CONTENT_SCAN
 562   { "malware_name",        vtype_stringptr,   &malware_name },
 563 #endif
 564   { "max_received_linelength", vtype_int,     &max_received_linelength },
 565   { "message_age",         vtype_int,         &message_age },
 566   { "message_body",        vtype_msgbody,     &message_body },
 567   { "message_body_end",    vtype_msgbody_end, &message_body_end },
 568   { "message_body_size",   vtype_int,         &message_body_size },
 569   { "message_exim_id",     vtype_stringptr,   &message_id },
 570   { "message_headers",     vtype_msgheaders,  NULL },
 571   { "message_headers_raw", vtype_msgheaders_raw, NULL },
 572   { "message_id",          vtype_stringptr,   &message_id },
 573   { "message_linecount",   vtype_int,         &message_linecount },
 574   { "message_size",        vtype_int,         &message_size },
 575 #ifdef EXPERIMENTAL_INTERNATIONAL
 576   { "message_smtputf8",    vtype_bool,        &message_smtputf8 },
 577 #endif
 578 #ifdef WITH_CONTENT_SCAN
 579   { "mime_anomaly_level",  vtype_int,         &mime_anomaly_level },
 580   { "mime_anomaly_text",   vtype_stringptr,   &mime_anomaly_text },
 581   { "mime_boundary",       vtype_stringptr,   &mime_boundary },
 582   { "mime_charset",        vtype_stringptr,   &mime_charset },
 583   { "mime_content_description", vtype_stringptr, &mime_content_description },
 584   { "mime_content_disposition", vtype_stringptr, &mime_content_disposition },
 585   { "mime_content_id",     vtype_stringptr,   &mime_content_id },
 586   { "mime_content_size",   vtype_int,         &mime_content_size },
 587   { "mime_content_transfer_encoding",vtype_stringptr, &mime_content_transfer_encoding },
 588   { "mime_content_type",   vtype_stringptr,   &mime_content_type },
 589   { "mime_decoded_filename", vtype_stringptr, &mime_decoded_filename },
 590   { "mime_filename",       vtype_stringptr,   &mime_filename },
 591   { "mime_is_coverletter", vtype_int,         &mime_is_coverletter },
 592   { "mime_is_multipart",   vtype_int,         &mime_is_multipart },
 593   { "mime_is_rfc822",      vtype_int,         &mime_is_rfc822 },
 594   { "mime_part_count",     vtype_int,         &mime_part_count },
 595 #endif
 596   { "n0",                  vtype_filter_int,  &filter_n[0] },
 597   { "n1",                  vtype_filter_int,  &filter_n[1] },
 598   { "n2",                  vtype_filter_int,  &filter_n[2] },
 599   { "n3",                  vtype_filter_int,  &filter_n[3] },
 600   { "n4",                  vtype_filter_int,  &filter_n[4] },
 601   { "n5",                  vtype_filter_int,  &filter_n[5] },
 602   { "n6",                  vtype_filter_int,  &filter_n[6] },
 603   { "n7",                  vtype_filter_int,  &filter_n[7] },
 604   { "n8",                  vtype_filter_int,  &filter_n[8] },
 605   { "n9",                  vtype_filter_int,  &filter_n[9] },
 606   { "original_domain",     vtype_stringptr,   &deliver_domain_orig },
 607   { "original_local_part", vtype_stringptr,   &deliver_localpart_orig },
 608   { "originator_gid",      vtype_gid,         &originator_gid },
 609   { "originator_uid",      vtype_uid,         &originator_uid },
 610   { "parent_domain",       vtype_stringptr,   &deliver_domain_parent },
 611   { "parent_local_part",   vtype_stringptr,   &deliver_localpart_parent },
 612   { "pid",                 vtype_pid,         NULL },
 613 #ifndef DISABLE_PRDR
 614   { "prdr_requested",      vtype_bool,        &prdr_requested },
 615 #endif
 616   { "primary_hostname",    vtype_stringptr,   &primary_hostname },
 617 #ifdef EXPERIMENTAL_PROXY
 618   { "proxy_host_address",  vtype_stringptr,   &proxy_host_address },
 619   { "proxy_host_port",     vtype_int,         &proxy_host_port },
 620   { "proxy_session",       vtype_bool,        &proxy_session },
 621   { "proxy_target_address",vtype_stringptr,   &proxy_target_address },
 622   { "proxy_target_port",   vtype_int,         &proxy_target_port },
 623 #endif
 624   { "prvscheck_address",   vtype_stringptr,   &prvscheck_address },
 625   { "prvscheck_keynum",    vtype_stringptr,   &prvscheck_keynum },
 626   { "prvscheck_result",    vtype_stringptr,   &prvscheck_result },
 627   { "qualify_domain",      vtype_stringptr,   &qualify_domain_sender },
 628   { "qualify_recipient",   vtype_stringptr,   &qualify_domain_recipient },
 629   { "rcpt_count",          vtype_int,         &rcpt_count },
 630   { "rcpt_defer_count",    vtype_int,         &rcpt_defer_count },
 631   { "rcpt_fail_count",     vtype_int,         &rcpt_fail_count },
 632   { "received_count",      vtype_int,         &received_count },
 633   { "received_for",        vtype_stringptr,   &received_for },
 634   { "received_ip_address", vtype_stringptr,   &interface_address },
 635   { "received_port",       vtype_int,         &interface_port },
 636   { "received_protocol",   vtype_stringptr,   &received_protocol },
 637   { "received_time",       vtype_int,         &received_time },
 638   { "recipient_data",      vtype_stringptr,   &recipient_data },
 639   { "recipient_verify_failure",vtype_stringptr,&recipient_verify_failure },
 640   { "recipients",          vtype_string_func, &fn_recipients },
 641   { "recipients_count",    vtype_int,         &recipients_count },
 642 #ifdef WITH_CONTENT_SCAN
 643   { "regex_match_string",  vtype_stringptr,   &regex_match_string },
 644 #endif
 645   { "reply_address",       vtype_reply,       NULL },
 646   { "return_path",         vtype_stringptr,   &return_path },
 647   { "return_size_limit",   vtype_int,         &bounce_return_size_limit },
 648   { "router_name",         vtype_stringptr,   &router_name },
 649   { "runrc",               vtype_int,         &runrc },
 650   { "self_hostname",       vtype_stringptr,   &self_hostname },
 651   { "sender_address",      vtype_stringptr,   &sender_address },
 652   { "sender_address_data", vtype_stringptr,   &sender_address_data },
 653   { "sender_address_domain", vtype_domain,    &sender_address },
 654   { "sender_address_local_part", vtype_localpart, &sender_address },
 655   { "sender_data",         vtype_stringptr,   &sender_data },
 656   { "sender_fullhost",     vtype_stringptr,   &sender_fullhost },
 657   { "sender_helo_dnssec",  vtype_bool,        &sender_helo_dnssec },
 658   { "sender_helo_name",    vtype_stringptr,   &sender_helo_name },
 659   { "sender_host_address", vtype_stringptr,   &sender_host_address },
 660   { "sender_host_authenticated",vtype_stringptr, &sender_host_authenticated },
 661   { "sender_host_dnssec",  vtype_bool,        &sender_host_dnssec },
 662   { "sender_host_name",    vtype_host_lookup, NULL },
 663   { "sender_host_port",    vtype_int,         &sender_host_port },
 664   { "sender_ident",        vtype_stringptr,   &sender_ident },
 665   { "sender_rate",         vtype_stringptr,   &sender_rate },
 666   { "sender_rate_limit",   vtype_stringptr,   &sender_rate_limit },
 667   { "sender_rate_period",  vtype_stringptr,   &sender_rate_period },
 668   { "sender_rcvhost",      vtype_stringptr,   &sender_rcvhost },
 669   { "sender_verify_failure",vtype_stringptr,  &sender_verify_failure },
 670   { "sending_ip_address",  vtype_stringptr,   &sending_ip_address },
 671   { "sending_port",        vtype_int,         &sending_port },
 672   { "smtp_active_hostname", vtype_stringptr,  &smtp_active_hostname },
 673   { "smtp_command",        vtype_stringptr,   &smtp_cmd_buffer },
 674   { "smtp_command_argument", vtype_stringptr, &smtp_cmd_argument },
 675   { "smtp_count_at_connection_start", vtype_int, &smtp_accept_count },
 676   { "smtp_notquit_reason", vtype_stringptr,   &smtp_notquit_reason },
 677   { "sn0",                 vtype_filter_int,  &filter_sn[0] },
 678   { "sn1",                 vtype_filter_int,  &filter_sn[1] },
 679   { "sn2",                 vtype_filter_int,  &filter_sn[2] },
 680   { "sn3",                 vtype_filter_int,  &filter_sn[3] },
 681   { "sn4",                 vtype_filter_int,  &filter_sn[4] },
 682   { "sn5",                 vtype_filter_int,  &filter_sn[5] },
 683   { "sn6",                 vtype_filter_int,  &filter_sn[6] },
 684   { "sn7",                 vtype_filter_int,  &filter_sn[7] },
 685   { "sn8",                 vtype_filter_int,  &filter_sn[8] },
 686   { "sn9",                 vtype_filter_int,  &filter_sn[9] },
 687 #ifdef WITH_CONTENT_SCAN
 688   { "spam_action",         vtype_stringptr,   &spam_action },
 689   { "spam_bar",            vtype_stringptr,   &spam_bar },
 690   { "spam_report",         vtype_stringptr,   &spam_report },
 691   { "spam_score",          vtype_stringptr,   &spam_score },
 692   { "spam_score_int",      vtype_stringptr,   &spam_score_int },
 693 #endif
 694 #ifdef EXPERIMENTAL_SPF
 695   { "spf_guess",           vtype_stringptr,   &spf_guess },
 696   { "spf_header_comment",  vtype_stringptr,   &spf_header_comment },
 697   { "spf_received",        vtype_stringptr,   &spf_received },
 698   { "spf_result",          vtype_stringptr,   &spf_result },
 699   { "spf_smtp_comment",    vtype_stringptr,   &spf_smtp_comment },
 700 #endif
 701   { "spool_directory",     vtype_stringptr,   &spool_directory },
 702   { "spool_inodes",        vtype_pinodes,     (void *)TRUE },
 703   { "spool_space",         vtype_pspace,      (void *)TRUE },
 704 #ifdef EXPERIMENTAL_SRS
 705   { "srs_db_address",      vtype_stringptr,   &srs_db_address },
 706   { "srs_db_key",          vtype_stringptr,   &srs_db_key },
 707   { "srs_orig_recipient",  vtype_stringptr,   &srs_orig_recipient },
 708   { "srs_orig_sender",     vtype_stringptr,   &srs_orig_sender },
 709   { "srs_recipient",       vtype_stringptr,   &srs_recipient },
 710   { "srs_status",          vtype_stringptr,   &srs_status },
 711 #endif
 712   { "thisaddress",         vtype_stringptr,   &filter_thisaddress },
 713
 714   /* The non-(in,out) variables are now deprecated */
 715   { "tls_bits",            vtype_int,         &tls_in.bits },
 716   { "tls_certificate_verified", vtype_int,    &tls_in.certificate_verified },
 717   { "tls_cipher",          vtype_stringptr,   &tls_in.cipher },
 718
 719   { "tls_in_bits",         vtype_int,         &tls_in.bits },
 720   { "tls_in_certificate_verified", vtype_int, &tls_in.certificate_verified },
 721   { "tls_in_cipher",       vtype_stringptr,   &tls_in.cipher },
 722   { "tls_in_ocsp",         vtype_int,         &tls_in.ocsp },
 723   { "tls_in_ourcert",      vtype_cert,        &tls_in.ourcert },
 724   { "tls_in_peercert",     vtype_cert,        &tls_in.peercert },
 725   { "tls_in_peerdn",       vtype_stringptr,   &tls_in.peerdn },
 726 #if defined(SUPPORT_TLS)
 727   { "tls_in_sni",          vtype_stringptr,   &tls_in.sni },
 728 #endif
 729   { "tls_out_bits",        vtype_int,         &tls_out.bits },
 730   { "tls_out_certificate_verified", vtype_int,&tls_out.certificate_verified },
 731   { "tls_out_cipher",      vtype_stringptr,   &tls_out.cipher },
 732 #ifdef EXPERIMENTAL_DANE
 733   { "tls_out_dane",        vtype_bool,        &tls_out.dane_verified },
 734 #endif
 735   { "tls_out_ocsp",        vtype_int,         &tls_out.ocsp },
 736   { "tls_out_ourcert",     vtype_cert,        &tls_out.ourcert },
 737   { "tls_out_peercert",    vtype_cert,        &tls_out.peercert },
 738   { "tls_out_peerdn",      vtype_stringptr,   &tls_out.peerdn },
 739 #if defined(SUPPORT_TLS)
 740   { "tls_out_sni",         vtype_stringptr,   &tls_out.sni },
 741 #endif
 742 #ifdef EXPERIMENTAL_DANE
 743   { "tls_out_tlsa_usage",  vtype_int,         &tls_out.tlsa_usage },
 744 #endif
 745
 746   { "tls_peerdn",          vtype_stringptr,   &tls_in.peerdn }, /* mind the alphabetical order! */
 747 #if defined(SUPPORT_TLS)
 748   { "tls_sni",             vtype_stringptr,   &tls_in.sni },    /* mind the alphabetical order! */
 749 #endif
 750
 751   { "tod_bsdinbox",        vtype_todbsdin,    NULL },
 752   { "tod_epoch",           vtype_tode,        NULL },
 753   { "tod_epoch_l",         vtype_todel,       NULL },
 754   { "tod_full",            vtype_todf,        NULL },
 755   { "tod_log",             vtype_todl,        NULL },
 756   { "tod_logfile",         vtype_todlf,       NULL },
 757   { "tod_zone",            vtype_todzone,     NULL },
 758   { "tod_zulu",            vtype_todzulu,     NULL },
 759   { "transport_name",      vtype_stringptr,   &transport_name },
 760   { "value",               vtype_stringptr,   &lookup_value },
 761   { "verify_mode",         vtype_stringptr,   &verify_mode },
 762   { "version_number",      vtype_stringptr,   &version_string },
 763   { "warn_message_delay",  vtype_stringptr,   &warnmsg_delay },
 764   { "warn_message_recipient",vtype_stringptr, &warnmsg_recipients },
 765   { "warn_message_recipients",vtype_stringptr,&warnmsg_recipients },
 766   { "warnmsg_delay",       vtype_stringptr,   &warnmsg_delay },
 767   { "warnmsg_recipient",   vtype_stringptr,   &warnmsg_recipients },
 768   { "warnmsg_recipients",  vtype_stringptr,   &warnmsg_recipients }
 769 };
 770
 771 static int var_table_size = nelem(var_table);
 772 static uschar var_buffer[256];
 773 static BOOL malformed_header;
 774
 775 /* For textual hashes */
 776
 777 static const char *hashcodes = "abcdefghijklmnopqrtsuvwxyz"
 778                                "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
 779                                "0123456789";
 780
 781 enum { HMAC_MD5, HMAC_SHA1 };
 782
 783 /* For numeric hashes */
 784
 785 static unsigned int prime[] = {
 786   2,   3,   5,   7,  11,  13,  17,  19,  23,  29,
 787  31,  37,  41,  43,  47,  53,  59,  61,  67,  71,
 788  73,  79,  83,  89,  97, 101, 103, 107, 109, 113};
 789
 790 /* For printing modes in symbolic form */
 791
 792 static uschar *mtable_normal[] =
 793   { US"---", US"--x", US"-w-", US"-wx", US"r--", US"r-x", US"rw-", US"rwx" };
 794
 795 static uschar *mtable_setid[] =
 796   { US"--S", US"--s", US"-wS", US"-ws", US"r-S", US"r-s", US"rwS", US"rws" };
 797
 798 static uschar *mtable_sticky[] =
 799   { US"--T", US"--t", US"-wT", US"-wt", US"r-T", US"r-t", US"rwT", US"rwt" };
 800
 801
 802
 803 /*************************************************
 804 *           Tables for UTF-8 support             *
 805 *************************************************/
 806
 807 /* Table of the number of extra characters, indexed by the first character
 808 masked with 0x3f. The highest number for a valid UTF-8 character is in fact
 809 0x3d. */
 810
 811 static uschar utf8_table1[] = {
 812   1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
 813   1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
 814   2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
 815   3,3,3,3,3,3,3,3,4,4,4,4,5,5,5,5 };
 816
 817 /* These are the masks for the data bits in the first byte of a character,
 818 indexed by the number of additional bytes. */
 819
 820 static int utf8_table2[] = { 0xff, 0x1f, 0x0f, 0x07, 0x03, 0x01};
 821
 822 /* Get the next UTF-8 character, advancing the pointer. */
 823
 824 #define GETUTF8INC(c, ptr) \
 825   c = *ptr++; \
 826   if ((c & 0xc0) == 0xc0) \
 827     { \
 828     int a = utf8_table1[c & 0x3f];  /* Number of additional bytes */ \
 829     int s = 6*a; \
 830     c = (c & utf8_table2[a]) << s; \
 831     while (a-- > 0) \
 832       { \
 833       s -= 6; \
 834       c |= (*ptr++ & 0x3f) << s; \
 835       } \
 836     }
 837
 838
 839 /*************************************************
 840 *           Binary chop search on a table        *
 841 *************************************************/
 842
 843 /* This is used for matching expansion items and operators.
 844
 845 Arguments:
 846   name        the name that is being sought
 847   table       the table to search
 848   table_size  the number of items in the table
 849
 850 Returns:      the offset in the table, or -1
 851 */
 852
 853 static int
 854 chop_match(uschar *name, uschar **table, int table_size)
 855 {
 856 uschar **bot = table;
 857 uschar **top = table + table_size;
 858
 859 while (top > bot)
 860   {
 861   uschar **mid = bot + (top - bot)/2;
 862   int c = Ustrcmp(name, *mid);
 863   if (c == 0) return mid - table;
 864   if (c > 0) bot = mid + 1; else top = mid;
 865   }
 866
 867 return -1;
 868 }
 869
 870
 871
 872 /*************************************************
 873 *          Check a condition string              *
 874 *************************************************/
 875
 876 /* This function is called to expand a string, and test the result for a "true"
 877 or "false" value. Failure of the expansion yields FALSE; logged unless it was a
 878 forced fail or lookup defer.
 879
 880 We used to release all store used, but this is not not safe due
 881 to ${dlfunc } and ${acl }.  In any case expand_string_internal()
 882 is reasonably careful to release what it can.
 883
 884 The actual false-value tests should be replicated for ECOND_BOOL_LAX.
 885
 886 Arguments:
 887   condition     the condition string
 888   m1            text to be incorporated in panic error
 889   m2            ditto
 890
 891 Returns:        TRUE if condition is met, FALSE if not
 892 */
 893
 894 BOOL
 895 expand_check_condition(uschar *condition, uschar *m1, uschar *m2)
 896 {
 897 int rc;
 898 uschar *ss = expand_string(condition);
 899 if (ss == NULL)
 900   {
 901   if (!expand_string_forcedfail && !search_find_defer)
 902     log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand condition \"%s\" "
 903       "for %s %s: %s", condition, m1, m2, expand_string_message);
 904   return FALSE;
 905   }
 906 rc = ss[0] != 0 && Ustrcmp(ss, "0") != 0 && strcmpic(ss, US"no") != 0 &&
 907   strcmpic(ss, US"false") != 0;
 908 return rc;
 909 }
 910
 911
 912
 913
 914 /*************************************************
 915 *        Pseudo-random number generation         *
 916 *************************************************/
 917
 918 /* Pseudo-random number generation.  The result is not "expected" to be
 919 cryptographically strong but not so weak that someone will shoot themselves
 920 in the foot using it as a nonce in some email header scheme or whatever
 921 weirdness they'll twist this into.  The result should ideally handle fork().
 922
 923 However, if we're stuck unable to provide this, then we'll fall back to
 924 appallingly bad randomness.
 925
 926 If SUPPORT_TLS is defined then this will not be used except as an emergency
 927 fallback.
 928
 929 Arguments:
 930   max       range maximum
 931 Returns     a random number in range [0, max-1]
 932 */
 933
 934 #ifdef SUPPORT_TLS
 935 # define vaguely_random_number vaguely_random_number_fallback
 936 #endif
 937 int
 938 vaguely_random_number(int max)
 939 {
 940 #ifdef SUPPORT_TLS
 941 # undef vaguely_random_number
 942 #endif
 943   static pid_t pid = 0;
 944   pid_t p2;
 945 #if defined(HAVE_SRANDOM) && !defined(HAVE_SRANDOMDEV)
 946   struct timeval tv;
 947 #endif
 948
 949   p2 = getpid();
 950   if (p2 != pid)
 951     {
 952     if (pid != 0)
 953       {
 954
 955 #ifdef HAVE_ARC4RANDOM
 956       /* cryptographically strong randomness, common on *BSD platforms, not
 957       so much elsewhere.  Alas. */
 958 #ifndef NOT_HAVE_ARC4RANDOM_STIR
 959       arc4random_stir();
 960 #endif
 961 #elif defined(HAVE_SRANDOM) || defined(HAVE_SRANDOMDEV)
 962 #ifdef HAVE_SRANDOMDEV
 963       /* uses random(4) for seeding */
 964       srandomdev();
 965 #else
 966       gettimeofday(&tv, NULL);
 967       srandom(tv.tv_sec | tv.tv_usec | getpid());
 968 #endif
 969 #else
 970       /* Poor randomness and no seeding here */
 971 #endif
 972
 973       }
 974     pid = p2;
 975     }
 976
 977 #ifdef HAVE_ARC4RANDOM
 978   return arc4random() % max;
 979 #elif defined(HAVE_SRANDOM) || defined(HAVE_SRANDOMDEV)
 980   return random() % max;
 981 #else
 982   /* This one returns a 16-bit number, definitely not crypto-strong */
 983   return random_number(max);
 984 #endif
 985 }
 986
 987
 988
 989
 990 /*************************************************
 991 *             Pick out a name from a string      *
 992 *************************************************/
 993
 994 /* If the name is too long, it is silently truncated.
 995
 996 Arguments:
 997   name      points to a buffer into which to put the name
 998   max       is the length of the buffer
 999   s         points to the first alphabetic character of the name
1000   extras    chars other than alphanumerics to permit
1001
1002 Returns:    pointer to the first character after the name
1003
1004 Note: The test for *s != 0 in the while loop is necessary because
1005 Ustrchr() yields non-NULL if the character is zero (which is not something
1006 I expected). */
1007
1008 static const uschar *
1009 read_name(uschar *name, int max, const uschar *s, uschar *extras)
1010 {
1011 int ptr = 0;
1012 while (*s != 0 && (isalnum(*s) || Ustrchr(extras, *s) != NULL))
1013   {
1014   if (ptr < max-1) name[ptr++] = *s;
1015   s++;
1016   }
1017 name[ptr] = 0;
1018 return s;
1019 }
1020
1021
1022
1023 /*************************************************
1024 *     Pick out the rest of a header name         *
1025 *************************************************/
1026
1027 /* A variable name starting $header_ (or just $h_ for those who like
1028 abbreviations) might not be the complete header name because headers can
1029 contain any printing characters in their names, except ':'. This function is
1030 called to read the rest of the name, chop h[eader]_ off the front, and put ':'
1031 on the end, if the name was terminated by white space.
1032
1033 Arguments:
1034   name      points to a buffer in which the name read so far exists
1035   max       is the length of the buffer
1036   s         points to the first character after the name so far, i.e. the
1037             first non-alphameric character after $header_xxxxx
1038
1039 Returns:    a pointer to the first character after the header name
1040 */
1041
1042 static const uschar *
1043 read_header_name(uschar *name, int max, const uschar *s)
1044 {
1045 int prelen = Ustrchr(name, '_') - name + 1;
1046 int ptr = Ustrlen(name) - prelen;
1047 if (ptr > 0) memmove(name, name+prelen, ptr);
1048 while (mac_isgraph(*s) && *s != ':')
1049   {
1050   if (ptr < max-1) name[ptr++] = *s;
1051   s++;
1052   }
1053 if (*s == ':') s++;
1054 name[ptr++] = ':';
1055 name[ptr] = 0;
1056 return s;
1057 }
1058
1059
1060
1061 /*************************************************
1062 *           Pick out a number from a string      *
1063 *************************************************/
1064
1065 /* Arguments:
1066   n     points to an integer into which to put the number
1067   s     points to the first digit of the number
1068
1069 Returns:  a pointer to the character after the last digit
1070 */
1071
1072 static uschar *
1073 read_number(int *n, uschar *s)
1074 {
1075 *n = 0;
1076 while (isdigit(*s)) *n = *n * 10 + (*s++ - '0');
1077 return s;
1078 }
1079
1080 static const uschar *
1081 read_cnumber(int *n, const uschar *s)
1082 {
1083 *n = 0;
1084 while (isdigit(*s)) *n = *n * 10 + (*s++ - '0');
1085 return s;
1086 }
1087
1088
1089
1090 /*************************************************
1091 *        Extract keyed subfield from a string    *
1092 *************************************************/
1093
1094 /* The yield is in dynamic store; NULL means that the key was not found.
1095
1096 Arguments:
1097   key       points to the name of the key
1098   s         points to the string from which to extract the subfield
1099
1100 Returns:    NULL if the subfield was not found, or
1101             a pointer to the subfield's data
1102 */
1103
1104 static uschar *
1105 expand_getkeyed(uschar *key, const uschar *s)
1106 {
1107 int length = Ustrlen(key);
1108 while (isspace(*s)) s++;
1109
1110 /* Loop to search for the key */
1111
1112 while (*s != 0)
1113   {
1114   int dkeylength;
1115   uschar *data;
1116   const uschar *dkey = s;
1117
1118   while (*s != 0 && *s != '=' && !isspace(*s)) s++;
1119   dkeylength = s - dkey;
1120   while (isspace(*s)) s++;
1121   if (*s == '=') while (isspace((*(++s))));
1122
1123   data = string_dequote(&s);
1124   if (length == dkeylength && strncmpic(key, dkey, length) == 0)
1125     return data;
1126
1127   while (isspace(*s)) s++;
1128   }
1129
1130 return NULL;
1131 }
1132
1133
1134
1135 static var_entry *
1136 find_var_ent(uschar * name)
1137 {
1138 int first = 0;
1139 int last = var_table_size;
1140
1141 while (last > first)
1142   {
1143   int middle = (first + last)/2;
1144   int c = Ustrcmp(name, var_table[middle].name);
1145
1146   if (c > 0) { first = middle + 1; continue; }
1147   if (c < 0) { last = middle; continue; }
1148   return &var_table[middle];
1149   }
1150 return NULL;
1151 }
1152
1153 /*************************************************
1154 *   Extract numbered subfield from string        *
1155 *************************************************/
1156
1157 /* Extracts a numbered field from a string that is divided by tokens - for
1158 example a line from /etc/passwd is divided by colon characters.  First field is
1159 numbered one.  Negative arguments count from the right. Zero returns the whole
1160 string. Returns NULL if there are insufficient tokens in the string
1161
1162 ***WARNING***
1163 Modifies final argument - this is a dynamically generated string, so that's OK.
1164
1165 Arguments:
1166   field       number of field to be extracted,
1167                 first field = 1, whole string = 0, last field = -1
1168   separators  characters that are used to break string into tokens
1169   s           points to the string from which to extract the subfield
1170
1171 Returns:      NULL if the field was not found,
1172               a pointer to the field's data inside s (modified to add 0)
1173 */
1174
1175 static uschar *
1176 expand_gettokened (int field, uschar *separators, uschar *s)
1177 {
1178 int sep = 1;
1179 int count;
1180 uschar *ss = s;
1181 uschar *fieldtext = NULL;
1182
1183 if (field == 0) return s;
1184
1185 /* Break the line up into fields in place; for field > 0 we stop when we have
1186 done the number of fields we want. For field < 0 we continue till the end of
1187 the string, counting the number of fields. */
1188
1189 count = (field > 0)? field : INT_MAX;
1190
1191 while (count-- > 0)
1192   {
1193   size_t len;
1194
1195   /* Previous field was the last one in the string. For a positive field
1196   number, this means there are not enough fields. For a negative field number,
1197   check that there are enough, and scan back to find the one that is wanted. */
1198
1199   if (sep == 0)
1200     {
1201     if (field > 0 || (-field) > (INT_MAX - count - 1)) return NULL;
1202     if ((-field) == (INT_MAX - count - 1)) return s;
1203     while (field++ < 0)
1204       {
1205       ss--;
1206       while (ss[-1] != 0) ss--;
1207       }
1208     fieldtext = ss;
1209     break;
1210     }
1211
1212   /* Previous field was not last in the string; save its start and put a
1213   zero at its end. */
1214
1215   fieldtext = ss;
1216   len = Ustrcspn(ss, separators);
1217   sep = ss[len];
1218   ss[len] = 0;
1219   ss += len + 1;
1220   }
1221
1222 return fieldtext;
1223 }
1224
1225
1226 static uschar *
1227 expand_getlistele(int field, const uschar * list)
1228 {
1229 const uschar * tlist= list;
1230 int sep= 0;
1231 uschar dummy;
1232
1233 if(field<0)
1234   {
1235   for(field++; string_nextinlist(&tlist, &sep, &dummy, 1); ) field++;
1236   sep= 0;
1237   }
1238 if(field==0) return NULL;
1239 while(--field>0 && (string_nextinlist(&list, &sep, &dummy, 1))) ;
1240 return string_nextinlist(&list, &sep, NULL, 0);
1241 }
1242
1243
1244 /* Certificate fields, by name.  Worry about by-OID later */
1245 /* Names are chosen to not have common prefixes */
1246
1247 #ifdef SUPPORT_TLS
1248 typedef struct
1249 {
1250 uschar * name;
1251 int      namelen;
1252 uschar * (*getfn)(void * cert, uschar * mod);
1253 } certfield;
1254 static certfield certfields[] =
1255 {                       /* linear search; no special order */
1256   { US"version",         7,  &tls_cert_version },
1257   { US"serial_number",   13, &tls_cert_serial_number },
1258   { US"subject",         7,  &tls_cert_subject },
1259   { US"notbefore",       9,  &tls_cert_not_before },
1260   { US"notafter",        8,  &tls_cert_not_after },
1261   { US"issuer",          6,  &tls_cert_issuer },
1262   { US"signature",       9,  &tls_cert_signature },
1263   { US"sig_algorithm",   13, &tls_cert_signature_algorithm },
1264   { US"subj_altname",    12, &tls_cert_subject_altname },
1265   { US"ocsp_uri",        8,  &tls_cert_ocsp_uri },
1266   { US"crl_uri",         7,  &tls_cert_crl_uri },
1267 };
1268
1269 static uschar *
1270 expand_getcertele(uschar * field, uschar * certvar)
1271 {
1272 var_entry * vp;
1273 certfield * cp;
1274
1275 if (!(vp = find_var_ent(certvar)))
1276   {
1277   expand_string_message =
1278     string_sprintf("no variable named \"%s\"", certvar);
1279   return NULL;          /* Unknown variable name */
1280   }
1281 /* NB this stops us passing certs around in variable.  Might
1282 want to do that in future */
1283 if (vp->type != vtype_cert)
1284   {
1285   expand_string_message =
1286     string_sprintf("\"%s\" is not a certificate", certvar);
1287   return NULL;          /* Unknown variable name */
1288   }
1289 if (!*(void **)vp->value)
1290   return NULL;
1291
1292 if (*field >= '0' && *field <= '9')
1293   return tls_cert_ext_by_oid(*(void **)vp->value, field, 0);
1294
1295 for(cp = certfields;
1296     cp < certfields + nelem(certfields);
1297     cp++)
1298   if (Ustrncmp(cp->name, field, cp->namelen) == 0)
1299     {
1300     uschar * modifier = *(field += cp->namelen) == ','
1301       ? ++field : NULL;
1302     return (*cp->getfn)( *(void **)vp->value, modifier );
1303     }
1304
1305 expand_string_message =
1306   string_sprintf("bad field selector \"%s\" for certextract", field);
1307 return NULL;
1308 }
1309 #endif  /*SUPPORT_TLS*/
1310
1311 /*************************************************
1312 *        Extract a substring from a string       *
1313 *************************************************/
1314
1315 /* Perform the ${substr or ${length expansion operations.
1316
1317 Arguments:
1318   subject     the input string
1319   value1      the offset from the start of the input string to the start of
1320                 the output string; if negative, count from the right.
1321   value2      the length of the output string, or negative (-1) for unset
1322                 if value1 is positive, unset means "all after"
1323                 if value1 is negative, unset means "all before"
1324   len         set to the length of the returned string
1325
1326 Returns:      pointer to the output string, or NULL if there is an error
1327 */
1328
1329 static uschar *
1330 extract_substr(uschar *subject, int value1, int value2, int *len)
1331 {
1332 int sublen = Ustrlen(subject);
1333
1334 if (value1 < 0)    /* count from right */
1335   {
1336   value1 += sublen;
1337
1338   /* If the position is before the start, skip to the start, and adjust the
1339   length. If the length ends up negative, the substring is null because nothing
1340   can precede. This falls out naturally when the length is unset, meaning "all
1341   to the left". */
1342
1343   if (value1 < 0)
1344     {
1345     value2 += value1;
1346     if (value2 < 0) value2 = 0;
1347     value1 = 0;
1348     }
1349
1350   /* Otherwise an unset length => characters before value1 */
1351
1352   else if (value2 < 0)
1353     {
1354     value2 = value1;
1355     value1 = 0;
1356     }
1357   }
1358
1359 /* For a non-negative offset, if the starting position is past the end of the
1360 string, the result will be the null string. Otherwise, an unset length means
1361 "rest"; just set it to the maximum - it will be cut down below if necessary. */
1362
1363 else
1364   {
1365   if (value1 > sublen)
1366     {
1367     value1 = sublen;
1368     value2 = 0;
1369     }
1370   else if (value2 < 0) value2 = sublen;
1371   }
1372
1373 /* Cut the length down to the maximum possible for the offset value, and get
1374 the required characters. */
1375
1376 if (value1 + value2 > sublen) value2 = sublen - value1;
1377 *len = value2;
1378 return subject + value1;
1379 }
1380
1381
1382
1383
1384 /*************************************************
1385 *            Old-style hash of a string          *
1386 *************************************************/
1387
1388 /* Perform the ${hash expansion operation.
1389
1390 Arguments:
1391   subject     the input string (an expanded substring)
1392   value1      the length of the output string; if greater or equal to the
1393                 length of the input string, the input string is returned
1394   value2      the number of hash characters to use, or 26 if negative
1395   len         set to the length of the returned string
1396
1397 Returns:      pointer to the output string, or NULL if there is an error
1398 */
1399
1400 static uschar *
1401 compute_hash(uschar *subject, int value1, int value2, int *len)
1402 {
1403 int sublen = Ustrlen(subject);
1404
1405 if (value2 < 0) value2 = 26;
1406 else if (value2 > Ustrlen(hashcodes))
1407   {
1408   expand_string_message =
1409     string_sprintf("hash count \"%d\" too big", value2);
1410   return NULL;
1411   }
1412
1413 /* Calculate the hash text. We know it is shorter than the original string, so
1414 can safely place it in subject[] (we know that subject is always itself an
1415 expanded substring). */
1416
1417 if (value1 < sublen)
1418   {
1419   int c;
1420   int i = 0;
1421   int j = value1;
1422   while ((c = (subject[j])) != 0)
1423     {
1424     int shift = (c + j++) & 7;
1425     subject[i] ^= (c << shift) | (c >> (8-shift));
1426     if (++i >= value1) i = 0;
1427     }
1428   for (i = 0; i < value1; i++)
1429     subject[i] = hashcodes[(subject[i]) % value2];
1430   }
1431 else value1 = sublen;
1432
1433 *len = value1;
1434 return subject;
1435 }
1436
1437
1438
1439
1440 /*************************************************
1441 *             Numeric hash of a string           *
1442 *************************************************/
1443
1444 /* Perform the ${nhash expansion operation. The first characters of the
1445 string are treated as most important, and get the highest prime numbers.
1446
1447 Arguments:
1448   subject     the input string
1449   value1      the maximum value of the first part of the result
1450   value2      the maximum value of the second part of the result,
1451                 or negative to produce only a one-part result
1452   len         set to the length of the returned string
1453
1454 Returns:  pointer to the output string, or NULL if there is an error.
1455 */
1456
1457 static uschar *
1458 compute_nhash (uschar *subject, int value1, int value2, int *len)
1459 {
1460 uschar *s = subject;
1461 int i = 0;
1462 unsigned long int total = 0; /* no overflow */
1463
1464 while (*s != 0)
1465   {
1466   if (i == 0) i = nelem(prime) - 1;
1467   total += prime[i--] * (unsigned int)(*s++);
1468   }
1469
1470 /* If value2 is unset, just compute one number */
1471
1472 if (value2 < 0)
1473   {
1474   s = string_sprintf("%d", total % value1);
1475   }
1476
1477 /* Otherwise do a div/mod hash */
1478
1479 else
1480   {
1481   total = total % (value1 * value2);
1482   s = string_sprintf("%d/%d", total/value2, total % value2);
1483   }
1484
1485 *len = Ustrlen(s);
1486 return s;
1487 }
1488
1489
1490
1491
1492
1493 /*************************************************
1494 *     Find the value of a header or headers      *
1495 *************************************************/
1496
1497 /* Multiple instances of the same header get concatenated, and this function
1498 can also return a concatenation of all the header lines. When concatenating
1499 specific headers that contain lists of addresses, a comma is inserted between
1500 them. Otherwise we use a straight concatenation. Because some messages can have
1501 pathologically large number of lines, there is a limit on the length that is
1502 returned. Also, to avoid massive store use which would result from using
1503 string_cat() as it copies and extends strings, we do a preliminary pass to find
1504 out exactly how much store will be needed. On "normal" messages this will be
1505 pretty trivial.
1506
1507 Arguments:
1508   name          the name of the header, without the leading $header_ or $h_,
1509                 or NULL if a concatenation of all headers is required
1510   exists_only   TRUE if called from a def: test; don't need to build a string;
1511                 just return a string that is not "" and not "0" if the header
1512                 exists
1513   newsize       return the size of memory block that was obtained; may be NULL
1514                 if exists_only is TRUE
1515   want_raw      TRUE if called for $rh_ or $rheader_ variables; no processing,
1516                 other than concatenating, will be done on the header. Also used
1517                 for $message_headers_raw.
1518   charset       name of charset to translate MIME words to; used only if
1519                 want_raw is false; if NULL, no translation is done (this is
1520                 used for $bh_ and $bheader_)
1521
1522 Returns:        NULL if the header does not exist, else a pointer to a new
1523                 store block
1524 */
1525
1526 static uschar *
1527 find_header(uschar *name, BOOL exists_only, int *newsize, BOOL want_raw,
1528   uschar *charset)
1529 {
1530 BOOL found = name == NULL;
1531 int comma = 0;
1532 int len = found? 0 : Ustrlen(name);
1533 int i;
1534 uschar *yield = NULL;
1535 uschar *ptr = NULL;
1536
1537 /* Loop for two passes - saves code repetition */
1538
1539 for (i = 0; i < 2; i++)
1540   {
1541   int size = 0;
1542   header_line *h;
1543
1544   for (h = header_list; size < header_insert_maxlen && h != NULL; h = h->next)
1545     {
1546     if (h->type != htype_old && h->text != NULL)  /* NULL => Received: placeholder */
1547       {
1548       if (name == NULL || (len <= h->slen && strncmpic(name, h->text, len) == 0))
1549         {
1550         int ilen;
1551         uschar *t;
1552
1553         if (exists_only) return US"1";      /* don't need actual string */
1554         found = TRUE;
1555         t = h->text + len;                  /* text to insert */
1556         if (!want_raw)                      /* unless wanted raw, */
1557           while (isspace(*t)) t++;          /* remove leading white space */
1558         ilen = h->slen - (t - h->text);     /* length to insert */
1559
1560         /* Unless wanted raw, remove trailing whitespace, including the
1561         newline. */
1562
1563         if (!want_raw)
1564           while (ilen > 0 && isspace(t[ilen-1])) ilen--;
1565
1566         /* Set comma = 1 if handling a single header and it's one of those
1567         that contains an address list, except when asked for raw headers. Only
1568         need to do this once. */
1569
1570         if (!want_raw && name != NULL && comma == 0 &&
1571             Ustrchr("BCFRST", h->type) != NULL)
1572           comma = 1;
1573
1574         /* First pass - compute total store needed; second pass - compute
1575         total store used, including this header. */
1576
1577         size += ilen + comma + 1;  /* +1 for the newline */
1578
1579         /* Second pass - concatentate the data, up to a maximum. Note that
1580         the loop stops when size hits the limit. */
1581
1582         if (i != 0)
1583           {
1584           if (size > header_insert_maxlen)
1585             {
1586             ilen -= size - header_insert_maxlen - 1;
1587             comma = 0;
1588             }
1589           Ustrncpy(ptr, t, ilen);
1590           ptr += ilen;
1591
1592           /* For a non-raw header, put in the comma if needed, then add
1593           back the newline we removed above, provided there was some text in
1594           the header. */
1595
1596           if (!want_raw && ilen > 0)
1597             {
1598             if (comma != 0) *ptr++ = ',';
1599             *ptr++ = '\n';
1600             }
1601           }
1602         }
1603       }
1604     }
1605
1606   /* At end of first pass, return NULL if no header found. Then truncate size
1607   if necessary, and get the buffer to hold the data, returning the buffer size.
1608   */
1609
1610   if (i == 0)
1611     {
1612     if (!found) return NULL;
1613     if (size > header_insert_maxlen) size = header_insert_maxlen;
1614     *newsize = size + 1;
1615     ptr = yield = store_get(*newsize);
1616     }
1617   }
1618
1619 /* That's all we do for raw header expansion. */
1620
1621 if (want_raw)
1622   {
1623   *ptr = 0;
1624   }
1625
1626 /* Otherwise, remove a final newline and a redundant added comma. Then we do
1627 RFC 2047 decoding, translating the charset if requested. The rfc2047_decode2()
1628 function can return an error with decoded data if the charset translation
1629 fails. If decoding fails, it returns NULL. */
1630
1631 else
1632   {
1633   uschar *decoded, *error;
1634   if (ptr > yield && ptr[-1] == '\n') ptr--;
1635   if (ptr > yield && comma != 0 && ptr[-1] == ',') ptr--;
1636   *ptr = 0;
1637   decoded = rfc2047_decode2(yield, check_rfc2047_length, charset, '?', NULL,
1638     newsize, &error);
1639   if (error != NULL)
1640     {
1641     DEBUG(D_any) debug_printf("*** error in RFC 2047 decoding: %s\n"
1642       "    input was: %s\n", error, yield);
1643     }
1644   if (decoded != NULL) yield = decoded;
1645   }
1646
1647 return yield;
1648 }
1649
1650
1651
1652
1653 /*************************************************
1654 *               Return list of recipients        *
1655 *************************************************/
1656 /* A recipients list is available only during system message filtering,
1657 during ACL processing after DATA, and while expanding pipe commands
1658 generated from a system filter, but not elsewhere. */
1659
1660 static uschar *
1661 fn_recipients(void)
1662 {
1663 if (!enable_dollar_recipients) return NULL; else
1664   {
1665   int size = 128;
1666   int ptr = 0;
1667   int i;
1668   uschar * s = store_get(size);
1669   for (i = 0; i < recipients_count; i++)
1670     {
1671     if (i != 0) s = string_cat(s, &size, &ptr, US", ", 2);
1672     s = string_cat(s, &size, &ptr, recipients_list[i].address,
1673       Ustrlen(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 == NULL)? (strict_acl_vars? NULL : US"") : node->data.ptr;
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   s = *((uschar **)(val));
1787   return (s == NULL)? US"" : s;
1788
1789   case vtype_pid:
1790   sprintf(CS var_buffer, "%d", (int)getpid()); /* pid */
1791   return var_buffer;
1792
1793   case vtype_load_avg:
1794   sprintf(CS var_buffer, "%d", OS_GETLOADAVG()); /* load_average */
1795   return var_buffer;
1796
1797   case vtype_host_lookup:                    /* Lookup if not done so */
1798   if (sender_host_name == NULL && sender_host_address != NULL &&
1799       !host_lookup_failed && host_name_lookup() == OK)
1800     host_build_sender_fullhost();
1801   return (sender_host_name == NULL)? US"" : sender_host_name;
1802
1803   case vtype_localpart:                      /* Get local part from address */
1804   s = *((uschar **)(val));
1805   if (s == NULL) return US"";
1806   domain = Ustrrchr(s, '@');
1807   if (domain == NULL) return s;
1808   if (domain - s > sizeof(var_buffer) - 1)
1809     log_write(0, LOG_MAIN|LOG_PANIC_DIE, "local part longer than " SIZE_T_FMT
1810         " in string expansion", sizeof(var_buffer));
1811   Ustrncpy(var_buffer, s, domain - s);
1812   var_buffer[domain - s] = 0;
1813   return var_buffer;
1814
1815   case vtype_domain:                         /* Get domain from address */
1816   s = *((uschar **)(val));
1817   if (s == NULL) return US"";
1818   domain = Ustrrchr(s, '@');
1819   return (domain == NULL)? US"" : domain + 1;
1820
1821   case vtype_msgheaders:
1822   return find_header(NULL, exists_only, newsize, FALSE, NULL);
1823
1824   case vtype_msgheaders_raw:
1825   return find_header(NULL, exists_only, newsize, TRUE, NULL);
1826
1827   case vtype_msgbody:                        /* Pointer to msgbody string */
1828   case vtype_msgbody_end:                    /* Ditto, the end of the msg */
1829   ss = (uschar **)(val);
1830   if (*ss == NULL && deliver_datafile >= 0)  /* Read body when needed */
1831     {
1832     uschar *body;
1833     off_t start_offset = SPOOL_DATA_START_OFFSET;
1834     int len = message_body_visible;
1835     if (len > message_size) len = message_size;
1836     *ss = body = store_malloc(len+1);
1837     body[0] = 0;
1838     if (vp->type == vtype_msgbody_end)
1839       {
1840       struct stat statbuf;
1841       if (fstat(deliver_datafile, &statbuf) == 0)
1842         {
1843         start_offset = statbuf.st_size - len;
1844         if (start_offset < SPOOL_DATA_START_OFFSET)
1845           start_offset = SPOOL_DATA_START_OFFSET;
1846         }
1847       }
1848     lseek(deliver_datafile, start_offset, SEEK_SET);
1849     len = read(deliver_datafile, body, len);
1850     if (len > 0)
1851       {
1852       body[len] = 0;
1853       if (message_body_newlines)   /* Separate loops for efficiency */
1854         {
1855         while (len > 0)
1856           { if (body[--len] == 0) body[len] = ' '; }
1857         }
1858       else
1859         {
1860         while (len > 0)
1861           { if (body[--len] == '\n' || body[len] == 0) body[len] = ' '; }
1862         }
1863       }
1864     }
1865   return (*ss == NULL)? US"" : *ss;
1866
1867   case vtype_todbsdin:                       /* BSD inbox time of day */
1868   return tod_stamp(tod_bsdin);
1869
1870   case vtype_tode:                           /* Unix epoch time of day */
1871   return tod_stamp(tod_epoch);
1872
1873   case vtype_todel:                          /* Unix epoch/usec time of day */
1874   return tod_stamp(tod_epoch_l);
1875
1876   case vtype_todf:                           /* Full time of day */
1877   return tod_stamp(tod_full);
1878
1879   case vtype_todl:                           /* Log format time of day */
1880   return tod_stamp(tod_log_bare);            /* (without timezone) */
1881
1882   case vtype_todzone:                        /* Time zone offset only */
1883   return tod_stamp(tod_zone);
1884
1885   case vtype_todzulu:                        /* Zulu time */
1886   return tod_stamp(tod_zulu);
1887
1888   case vtype_todlf:                          /* Log file datestamp tod */
1889   return tod_stamp(tod_log_datestamp_daily);
1890
1891   case vtype_reply:                          /* Get reply address */
1892   s = find_header(US"reply-to:", exists_only, newsize, TRUE,
1893     headers_charset);
1894   if (s != NULL) while (isspace(*s)) s++;
1895   if (s == NULL || *s == 0)
1896     {
1897     *newsize = 0;                            /* For the *s==0 case */
1898     s = find_header(US"from:", exists_only, newsize, TRUE, headers_charset);
1899     }
1900   if (s != NULL)
1901     {
1902     uschar *t;
1903     while (isspace(*s)) s++;
1904     for (t = s; *t != 0; t++) if (*t == '\n') *t = ' ';
1905     while (t > s && isspace(t[-1])) t--;
1906     *t = 0;
1907     }
1908   return (s == NULL)? US"" : s;
1909
1910   case vtype_string_func:
1911     {
1912     uschar * (*fn)() = val;
1913     return fn();
1914     }
1915
1916   case vtype_pspace:
1917     {
1918     int inodes;
1919     sprintf(CS var_buffer, "%d",
1920       receive_statvfs(val == (void *)TRUE, &inodes));
1921     }
1922   return var_buffer;
1923
1924   case vtype_pinodes:
1925     {
1926     int inodes;
1927     (void) receive_statvfs(val == (void *)TRUE, &inodes);
1928     sprintf(CS var_buffer, "%d", inodes);
1929     }
1930   return var_buffer;
1931
1932   case vtype_cert:
1933   return *(void **)val ? US"<cert>" : US"";
1934
1935   #ifndef DISABLE_DKIM
1936   case vtype_dkim:
1937   return dkim_exim_expand_query((int)(long)val);
1938   #endif
1939
1940   }
1941
1942 return NULL;  /* Unknown variable. Silences static checkers. */
1943 }
1944
1945
1946
1947
1948 void
1949 modify_variable(uschar *name, void * value)
1950 {
1951 var_entry * vp;
1952 if ((vp = find_var_ent(name))) vp->value = value;
1953 return;          /* Unknown variable name, fail silently */
1954 }
1955
1956
1957
1958
1959
1960 /*************************************************
1961 *           Read and expand substrings           *
1962 *************************************************/
1963
1964 /* This function is called to read and expand argument substrings for various
1965 expansion items. Some have a minimum requirement that is less than the maximum;
1966 in these cases, the first non-present one is set to NULL.
1967
1968 Arguments:
1969   sub        points to vector of pointers to set
1970   n          maximum number of substrings
1971   m          minimum required
1972   sptr       points to current string pointer
1973   skipping   the skipping flag
1974   check_end  if TRUE, check for final '}'
1975   name       name of item, for error message
1976   resetok    if not NULL, pointer to flag - write FALSE if unsafe to reset
1977              the store.
1978
1979 Returns:     0 OK; string pointer updated
1980              1 curly bracketing error (too few arguments)
1981              2 too many arguments (only if check_end is set); message set
1982              3 other error (expansion failure)
1983 */
1984
1985 static int
1986 read_subs(uschar **sub, int n, int m, const uschar **sptr, BOOL skipping,
1987   BOOL check_end, uschar *name, BOOL *resetok)
1988 {
1989 int i;
1990 const uschar *s = *sptr;
1991
1992 while (isspace(*s)) s++;
1993 for (i = 0; i < n; i++)
1994   {
1995   if (*s != '{')
1996     {
1997     if (i < m) return 1;
1998     sub[i] = NULL;
1999     break;
2000     }
2001   sub[i] = expand_string_internal(s+1, TRUE, &s, skipping, TRUE, resetok);
2002   if (sub[i] == NULL) return 3;
2003   if (*s++ != '}') return 1;
2004   while (isspace(*s)) s++;
2005   }
2006 if (check_end && *s++ != '}')
2007   {
2008   if (s[-1] == '{')
2009     {
2010     expand_string_message = string_sprintf("Too many arguments for \"%s\" "
2011       "(max is %d)", name, n);
2012     return 2;
2013     }
2014   return 1;
2015   }
2016
2017 *sptr = s;
2018 return 0;
2019 }
2020
2021
2022
2023
2024 /*************************************************
2025 *     Elaborate message for bad variable         *
2026 *************************************************/
2027
2028 /* For the "unknown variable" message, take a look at the variable's name, and
2029 give additional information about possible ACL variables. The extra information
2030 is added on to expand_string_message.
2031
2032 Argument:   the name of the variable
2033 Returns:    nothing
2034 */
2035
2036 static void
2037 check_variable_error_message(uschar *name)
2038 {
2039 if (Ustrncmp(name, "acl_", 4) == 0)
2040   expand_string_message = string_sprintf("%s (%s)", expand_string_message,
2041     (name[4] == 'c' || name[4] == 'm')?
2042       (isalpha(name[5])?
2043         US"6th character of a user-defined ACL variable must be a digit or underscore" :
2044         US"strict_acl_vars is set"    /* Syntax is OK, it has to be this */
2045       ) :
2046       US"user-defined ACL variables must start acl_c or acl_m");
2047 }
2048
2049
2050
2051 /*
2052 Load args from sub array to globals, and call acl_check().
2053 Sub array will be corrupted on return.
2054
2055 Returns:       OK         access is granted by an ACCEPT verb
2056                DISCARD    access is granted by a DISCARD verb
2057                FAIL       access is denied
2058                FAIL_DROP  access is denied; drop the connection
2059                DEFER      can't tell at the moment
2060                ERROR      disaster
2061 */
2062 static int
2063 eval_acl(uschar ** sub, int nsub, uschar ** user_msgp)
2064 {
2065 int i;
2066 int sav_narg = acl_narg;
2067 int ret;
2068 uschar * dummy_logmsg;
2069 extern int acl_where;
2070
2071 if(--nsub > nelem(acl_arg)) nsub = nelem(acl_arg);
2072 for (i = 0; i < nsub && sub[i+1]; i++)
2073   {
2074   uschar * tmp = acl_arg[i];
2075   acl_arg[i] = sub[i+1];        /* place callers args in the globals */
2076   sub[i+1] = tmp;               /* stash the old args using our caller's storage */
2077   }
2078 acl_narg = i;
2079 while (i < nsub)
2080   {
2081   sub[i+1] = acl_arg[i];
2082   acl_arg[i++] = NULL;
2083   }
2084
2085 DEBUG(D_expand)
2086   debug_printf("expanding: acl: %s  arg: %s%s\n",
2087     sub[0],
2088     acl_narg>0 ? acl_arg[0] : US"<none>",
2089     acl_narg>1 ? " +more"   : "");
2090
2091 ret = acl_eval(acl_where, sub[0], user_msgp, &dummy_logmsg);
2092
2093 for (i = 0; i < nsub; i++)
2094   acl_arg[i] = sub[i+1];        /* restore old args */
2095 acl_narg = sav_narg;
2096
2097 return ret;
2098 }
2099
2100
2101
2102
2103 /*************************************************
2104 *        Read and evaluate a condition           *
2105 *************************************************/
2106
2107 /*
2108 Arguments:
2109   s        points to the start of the condition text
2110   resetok  points to a BOOL which is written false if it is unsafe to
2111            free memory. Certain condition types (acl) may have side-effect
2112            allocation which must be preserved.
2113   yield    points to a BOOL to hold the result of the condition test;
2114            if NULL, we are just reading through a condition that is
2115            part of an "or" combination to check syntax, or in a state
2116            where the answer isn't required
2117
2118 Returns:   a pointer to the first character after the condition, or
2119            NULL after an error
2120 */
2121
2122 static const uschar *
2123 eval_condition(const uschar *s, BOOL *resetok, BOOL *yield)
2124 {
2125 BOOL testfor = TRUE;
2126 BOOL tempcond, combined_cond;
2127 BOOL *subcondptr;
2128 BOOL sub2_honour_dollar = TRUE;
2129 int i, rc, cond_type, roffset;
2130 int_eximarith_t num[2];
2131 struct stat statbuf;
2132 uschar name[256];
2133 const uschar *sub[10];
2134
2135 const pcre *re;
2136 const uschar *rerror;
2137
2138 for (;;)
2139   {
2140   while (isspace(*s)) s++;
2141   if (*s == '!') { testfor = !testfor; s++; } else break;
2142   }
2143
2144 /* Numeric comparisons are symbolic */
2145
2146 if (*s == '=' || *s == '>' || *s == '<')
2147   {
2148   int p = 0;
2149   name[p++] = *s++;
2150   if (*s == '=')
2151     {
2152     name[p++] = '=';
2153     s++;
2154     }
2155   name[p] = 0;
2156   }
2157
2158 /* All other conditions are named */
2159
2160 else s = read_name(name, 256, s, US"_");
2161
2162 /* If we haven't read a name, it means some non-alpha character is first. */
2163
2164 if (name[0] == 0)
2165   {
2166   expand_string_message = string_sprintf("condition name expected, "
2167     "but found \"%.16s\"", s);
2168   return NULL;
2169   }
2170
2171 /* Find which condition we are dealing with, and switch on it */
2172
2173 cond_type = chop_match(name, cond_table, nelem(cond_table));
2174 switch(cond_type)
2175   {
2176   /* def: tests for a non-empty variable, or for the existence of a header. If
2177   yield == NULL we are in a skipping state, and don't care about the answer. */
2178
2179   case ECOND_DEF:
2180   if (*s != ':')
2181     {
2182     expand_string_message = US"\":\" expected after \"def\"";
2183     return NULL;
2184     }
2185
2186   s = read_name(name, 256, s+1, US"_");
2187
2188   /* Test for a header's existence. If the name contains a closing brace
2189   character, this may be a user error where the terminating colon has been
2190   omitted. Set a flag to adjust a subsequent error message in this case. */
2191
2192   if (Ustrncmp(name, "h_", 2) == 0 ||
2193       Ustrncmp(name, "rh_", 3) == 0 ||
2194       Ustrncmp(name, "bh_", 3) == 0 ||
2195       Ustrncmp(name, "header_", 7) == 0 ||
2196       Ustrncmp(name, "rheader_", 8) == 0 ||
2197       Ustrncmp(name, "bheader_", 8) == 0)
2198     {
2199     s = read_header_name(name, 256, s);
2200     /* {-for-text-editors */
2201     if (Ustrchr(name, '}') != NULL) malformed_header = TRUE;
2202     if (yield != NULL) *yield =
2203       (find_header(name, TRUE, NULL, FALSE, NULL) != NULL) == testfor;
2204     }
2205
2206   /* Test for a variable's having a non-empty value. A non-existent variable
2207   causes an expansion failure. */
2208
2209   else
2210     {
2211     uschar *value = find_variable(name, TRUE, yield == NULL, NULL);
2212     if (value == NULL)
2213       {
2214       expand_string_message = (name[0] == 0)?
2215         string_sprintf("variable name omitted after \"def:\"") :
2216         string_sprintf("unknown variable \"%s\" after \"def:\"", name);
2217       check_variable_error_message(name);
2218       return NULL;
2219       }
2220     if (yield != NULL) *yield = (value[0] != 0) == testfor;
2221     }
2222
2223   return s;
2224
2225
2226   /* first_delivery tests for first delivery attempt */
2227
2228   case ECOND_FIRST_DELIVERY:
2229   if (yield != NULL) *yield = deliver_firsttime == testfor;
2230   return s;
2231
2232
2233   /* queue_running tests for any process started by a queue runner */
2234
2235   case ECOND_QUEUE_RUNNING:
2236   if (yield != NULL) *yield = (queue_run_pid != (pid_t)0) == testfor;
2237   return s;
2238
2239
2240   /* exists:  tests for file existence
2241        isip:  tests for any IP address
2242       isip4:  tests for an IPv4 address
2243       isip6:  tests for an IPv6 address
2244         pam:  does PAM authentication
2245      radius:  does RADIUS authentication
2246    ldapauth:  does LDAP authentication
2247     pwcheck:  does Cyrus SASL pwcheck authentication
2248   */
2249
2250   case ECOND_EXISTS:
2251   case ECOND_ISIP:
2252   case ECOND_ISIP4:
2253   case ECOND_ISIP6:
2254   case ECOND_PAM:
2255   case ECOND_RADIUS:
2256   case ECOND_LDAPAUTH:
2257   case ECOND_PWCHECK:
2258
2259   while (isspace(*s)) s++;
2260   if (*s != '{') goto COND_FAILED_CURLY_START;          /* }-for-text-editors */
2261
2262   sub[0] = expand_string_internal(s+1, TRUE, &s, yield == NULL, TRUE, resetok);
2263   if (sub[0] == NULL) return NULL;
2264   /* {-for-text-editors */
2265   if (*s++ != '}') goto COND_FAILED_CURLY_END;
2266
2267   if (yield == NULL) return s;   /* No need to run the test if skipping */
2268
2269   switch(cond_type)
2270     {
2271     case ECOND_EXISTS:
2272     if ((expand_forbid & RDO_EXISTS) != 0)
2273       {
2274       expand_string_message = US"File existence tests are not permitted";
2275       return NULL;
2276       }
2277     *yield = (Ustat(sub[0], &statbuf) == 0) == testfor;
2278     break;
2279
2280     case ECOND_ISIP:
2281     case ECOND_ISIP4:
2282     case ECOND_ISIP6:
2283     rc = string_is_ip_address(sub[0], NULL);
2284     *yield = ((cond_type == ECOND_ISIP)? (rc != 0) :
2285              (cond_type == ECOND_ISIP4)? (rc == 4) : (rc == 6)) == testfor;
2286     break;
2287
2288     /* Various authentication tests - all optionally compiled */
2289
2290     case ECOND_PAM:
2291     #ifdef SUPPORT_PAM
2292     rc = auth_call_pam(sub[0], &expand_string_message);
2293     goto END_AUTH;
2294     #else
2295     goto COND_FAILED_NOT_COMPILED;
2296     #endif  /* SUPPORT_PAM */
2297
2298     case ECOND_RADIUS:
2299     #ifdef RADIUS_CONFIG_FILE
2300     rc = auth_call_radius(sub[0], &expand_string_message);
2301     goto END_AUTH;
2302     #else
2303     goto COND_FAILED_NOT_COMPILED;
2304     #endif  /* RADIUS_CONFIG_FILE */
2305
2306     case ECOND_LDAPAUTH:
2307     #ifdef LOOKUP_LDAP
2308       {
2309       /* Just to keep the interface the same */
2310       BOOL do_cache;
2311       int old_pool = store_pool;
2312       store_pool = POOL_SEARCH;
2313       rc = eldapauth_find((void *)(-1), NULL, sub[0], Ustrlen(sub[0]), NULL,
2314         &expand_string_message, &do_cache);
2315       store_pool = old_pool;
2316       }
2317     goto END_AUTH;
2318     #else
2319     goto COND_FAILED_NOT_COMPILED;
2320     #endif  /* LOOKUP_LDAP */
2321
2322     case ECOND_PWCHECK:
2323     #ifdef CYRUS_PWCHECK_SOCKET
2324     rc = auth_call_pwcheck(sub[0], &expand_string_message);
2325     goto END_AUTH;
2326     #else
2327     goto COND_FAILED_NOT_COMPILED;
2328     #endif  /* CYRUS_PWCHECK_SOCKET */
2329
2330     #if defined(SUPPORT_PAM) || defined(RADIUS_CONFIG_FILE) || \
2331         defined(LOOKUP_LDAP) || defined(CYRUS_PWCHECK_SOCKET)
2332     END_AUTH:
2333     if (rc == ERROR || rc == DEFER) return NULL;
2334     *yield = (rc == OK) == testfor;
2335     #endif
2336     }
2337   return s;
2338
2339
2340   /* call ACL (in a conditional context).  Accept true, deny false.
2341   Defer is a forced-fail.  Anything set by message= goes to $value.
2342   Up to ten parameters are used; we use the braces round the name+args
2343   like the saslauthd condition does, to permit a variable number of args.
2344   See also the expansion-item version EITEM_ACL and the traditional
2345   acl modifier ACLC_ACL.
2346   Since the ACL may allocate new global variables, tell our caller to not
2347   reclaim memory.
2348   */
2349
2350   case ECOND_ACL:
2351     /* ${if acl {{name}{arg1}{arg2}...}  {yes}{no}} */
2352     {
2353     uschar *sub[10];
2354     uschar *user_msg;
2355     BOOL cond = FALSE;
2356     int size = 0;
2357     int ptr = 0;
2358
2359     while (isspace(*s)) s++;
2360     if (*s++ != '{') goto COND_FAILED_CURLY_START;      /*}*/
2361
2362     switch(read_subs(sub, nelem(sub), 1,
2363       &s, yield == NULL, TRUE, US"acl", resetok))
2364       {
2365       case 1: expand_string_message = US"too few arguments or bracketing "
2366         "error for acl";
2367       case 2:
2368       case 3: return NULL;
2369       }
2370
2371     *resetok = FALSE;
2372     if (yield != NULL) switch(eval_acl(sub, nelem(sub), &user_msg))
2373         {
2374         case OK:
2375           cond = TRUE;
2376         case FAIL:
2377           lookup_value = NULL;
2378           if (user_msg)
2379             {
2380             lookup_value = string_cat(NULL, &size, &ptr, user_msg, Ustrlen(user_msg));
2381             lookup_value[ptr] = '\0';
2382             }
2383           *yield = cond == testfor;
2384           break;
2385
2386         case DEFER:
2387           expand_string_forcedfail = TRUE;
2388         default:
2389           expand_string_message = string_sprintf("error from acl \"%s\"", sub[0]);
2390           return NULL;
2391         }
2392     return s;
2393     }
2394
2395
2396   /* saslauthd: does Cyrus saslauthd authentication. Four parameters are used:
2397
2398      ${if saslauthd {{username}{password}{service}{realm}}  {yes}{no}}
2399
2400   However, the last two are optional. That is why the whole set is enclosed
2401   in their own set of braces. */
2402
2403   case ECOND_SASLAUTHD:
2404 #ifndef CYRUS_SASLAUTHD_SOCKET
2405     goto COND_FAILED_NOT_COMPILED;
2406 #else
2407     {
2408     uschar *sub[4];
2409     while (isspace(*s)) s++;
2410     if (*s++ != '{') goto COND_FAILED_CURLY_START;      /* }-for-text-editors */
2411     switch(read_subs(sub, nelem(sub), 2, &s, yield == NULL, TRUE, US"saslauthd",
2412                     resetok))
2413       {
2414       case 1: expand_string_message = US"too few arguments or bracketing "
2415         "error for saslauthd";
2416       case 2:
2417       case 3: return NULL;
2418       }
2419     if (sub[2] == NULL) sub[3] = NULL;  /* realm if no service */
2420     if (yield != NULL)
2421       {
2422       int rc = auth_call_saslauthd(sub[0], sub[1], sub[2], sub[3],
2423         &expand_string_message);
2424       if (rc == ERROR || rc == DEFER) return NULL;
2425       *yield = (rc == OK) == testfor;
2426       }
2427     return s;
2428     }
2429 #endif /* CYRUS_SASLAUTHD_SOCKET */
2430
2431
2432   /* symbolic operators for numeric and string comparison, and a number of
2433   other operators, all requiring two arguments.
2434
2435   crypteq:           encrypts plaintext and compares against an encrypted text,
2436                        using crypt(), crypt16(), MD5 or SHA-1
2437   inlist/inlisti:    checks if first argument is in the list of the second
2438   match:             does a regular expression match and sets up the numerical
2439                        variables if it succeeds
2440   match_address:     matches in an address list
2441   match_domain:      matches in a domain list
2442   match_ip:          matches a host list that is restricted to IP addresses
2443   match_local_part:  matches in a local part list
2444   */
2445
2446   case ECOND_MATCH_ADDRESS:
2447   case ECOND_MATCH_DOMAIN:
2448   case ECOND_MATCH_IP:
2449   case ECOND_MATCH_LOCAL_PART:
2450 #ifndef EXPAND_LISTMATCH_RHS
2451     sub2_honour_dollar = FALSE;
2452 #endif
2453     /* FALLTHROUGH */
2454
2455   case ECOND_CRYPTEQ:
2456   case ECOND_INLIST:
2457   case ECOND_INLISTI:
2458   case ECOND_MATCH:
2459
2460   case ECOND_NUM_L:     /* Numerical comparisons */
2461   case ECOND_NUM_LE:
2462   case ECOND_NUM_E:
2463   case ECOND_NUM_EE:
2464   case ECOND_NUM_G:
2465   case ECOND_NUM_GE:
2466
2467   case ECOND_STR_LT:    /* String comparisons */
2468   case ECOND_STR_LTI:
2469   case ECOND_STR_LE:
2470   case ECOND_STR_LEI:
2471   case ECOND_STR_EQ:
2472   case ECOND_STR_EQI:
2473   case ECOND_STR_GT:
2474   case ECOND_STR_GTI:
2475   case ECOND_STR_GE:
2476   case ECOND_STR_GEI:
2477
2478   for (i = 0; i < 2; i++)
2479     {
2480     /* Sometimes, we don't expand substrings; too many insecure configurations
2481     created using match_address{}{} and friends, where the second param
2482     includes information from untrustworthy sources. */
2483     BOOL honour_dollar = TRUE;
2484     if ((i > 0) && !sub2_honour_dollar)
2485       honour_dollar = FALSE;
2486
2487     while (isspace(*s)) s++;
2488     if (*s != '{')
2489       {
2490       if (i == 0) goto COND_FAILED_CURLY_START;
2491       expand_string_message = string_sprintf("missing 2nd string in {} "
2492         "after \"%s\"", name);
2493       return NULL;
2494       }
2495     sub[i] = expand_string_internal(s+1, TRUE, &s, yield == NULL,
2496         honour_dollar, resetok);
2497     if (sub[i] == NULL) return NULL;
2498     if (*s++ != '}') goto COND_FAILED_CURLY_END;
2499
2500     /* Convert to numerical if required; we know that the names of all the
2501     conditions that compare numbers do not start with a letter. This just saves
2502     checking for them individually. */
2503
2504     if (!isalpha(name[0]) && yield != NULL)
2505       {
2506       if (sub[i][0] == 0)
2507         {
2508         num[i] = 0;
2509         DEBUG(D_expand)
2510           debug_printf("empty string cast to zero for numerical comparison\n");
2511         }
2512       else
2513         {
2514         num[i] = expanded_string_integer(sub[i], FALSE);
2515         if (expand_string_message != NULL) return NULL;
2516         }
2517       }
2518     }
2519
2520   /* Result not required */
2521
2522   if (yield == NULL) return s;
2523
2524   /* Do an appropriate comparison */
2525
2526   switch(cond_type)
2527     {
2528     case ECOND_NUM_E:
2529     case ECOND_NUM_EE:
2530     tempcond = (num[0] == num[1]);
2531     break;
2532
2533     case ECOND_NUM_G:
2534     tempcond = (num[0] > num[1]);
2535     break;
2536
2537     case ECOND_NUM_GE:
2538     tempcond = (num[0] >= num[1]);
2539     break;
2540
2541     case ECOND_NUM_L:
2542     tempcond = (num[0] < num[1]);
2543     break;
2544
2545     case ECOND_NUM_LE:
2546     tempcond = (num[0] <= num[1]);
2547     break;
2548
2549     case ECOND_STR_LT:
2550     tempcond = (Ustrcmp(sub[0], sub[1]) < 0);
2551     break;
2552
2553     case ECOND_STR_LTI:
2554     tempcond = (strcmpic(sub[0], sub[1]) < 0);
2555     break;
2556
2557     case ECOND_STR_LE:
2558     tempcond = (Ustrcmp(sub[0], sub[1]) <= 0);
2559     break;
2560
2561     case ECOND_STR_LEI:
2562     tempcond = (strcmpic(sub[0], sub[1]) <= 0);
2563     break;
2564
2565     case ECOND_STR_EQ:
2566     tempcond = (Ustrcmp(sub[0], sub[1]) == 0);
2567     break;
2568
2569     case ECOND_STR_EQI:
2570     tempcond = (strcmpic(sub[0], sub[1]) == 0);
2571     break;
2572
2573     case ECOND_STR_GT:
2574     tempcond = (Ustrcmp(sub[0], sub[1]) > 0);
2575     break;
2576
2577     case ECOND_STR_GTI:
2578     tempcond = (strcmpic(sub[0], sub[1]) > 0);
2579     break;
2580
2581     case ECOND_STR_GE:
2582     tempcond = (Ustrcmp(sub[0], sub[1]) >= 0);
2583     break;
2584
2585     case ECOND_STR_GEI:
2586     tempcond = (strcmpic(sub[0], sub[1]) >= 0);
2587     break;
2588
2589     case ECOND_MATCH:   /* Regular expression match */
2590     re = pcre_compile(CS sub[1], PCRE_COPT, (const char **)&rerror, &roffset,
2591       NULL);
2592     if (re == NULL)
2593       {
2594       expand_string_message = string_sprintf("regular expression error in "
2595         "\"%s\": %s at offset %d", sub[1], rerror, roffset);
2596       return NULL;
2597       }
2598     tempcond = regex_match_and_setup(re, sub[0], 0, -1);
2599     break;
2600
2601     case ECOND_MATCH_ADDRESS:  /* Match in an address list */
2602     rc = match_address_list(sub[0], TRUE, FALSE, &(sub[1]), NULL, -1, 0, NULL);
2603     goto MATCHED_SOMETHING;
2604
2605     case ECOND_MATCH_DOMAIN:   /* Match in a domain list */
2606     rc = match_isinlist(sub[0], &(sub[1]), 0, &domainlist_anchor, NULL,
2607       MCL_DOMAIN + MCL_NOEXPAND, TRUE, NULL);
2608     goto MATCHED_SOMETHING;
2609
2610     case ECOND_MATCH_IP:       /* Match IP address in a host list */
2611     if (sub[0][0] != 0 && string_is_ip_address(sub[0], NULL) == 0)
2612       {
2613       expand_string_message = string_sprintf("\"%s\" is not an IP address",
2614         sub[0]);
2615       return NULL;
2616       }
2617     else
2618       {
2619       unsigned int *nullcache = NULL;
2620       check_host_block cb;
2621
2622       cb.host_name = US"";
2623       cb.host_address = sub[0];
2624
2625       /* If the host address starts off ::ffff: it is an IPv6 address in
2626       IPv4-compatible mode. Find the IPv4 part for checking against IPv4
2627       addresses. */
2628
2629       cb.host_ipv4 = (Ustrncmp(cb.host_address, "::ffff:", 7) == 0)?
2630         cb.host_address + 7 : cb.host_address;
2631
2632       rc = match_check_list(
2633              &sub[1],                   /* the list */
2634              0,                         /* separator character */
2635              &hostlist_anchor,          /* anchor pointer */
2636              &nullcache,                /* cache pointer */
2637              check_host,                /* function for testing */
2638              &cb,                       /* argument for function */
2639              MCL_HOST,                  /* type of check */
2640              sub[0],                    /* text for debugging */
2641              NULL);                     /* where to pass back data */
2642       }
2643     goto MATCHED_SOMETHING;
2644
2645     case ECOND_MATCH_LOCAL_PART:
2646     rc = match_isinlist(sub[0], &(sub[1]), 0, &localpartlist_anchor, NULL,
2647       MCL_LOCALPART + MCL_NOEXPAND, TRUE, NULL);
2648     /* Fall through */
2649     /* VVVVVVVVVVVV */
2650     MATCHED_SOMETHING:
2651     switch(rc)
2652       {
2653       case OK:
2654       tempcond = TRUE;
2655       break;
2656
2657       case FAIL:
2658       tempcond = FALSE;
2659       break;
2660
2661       case DEFER:
2662       expand_string_message = string_sprintf("unable to complete match "
2663         "against \"%s\": %s", sub[1], search_error_message);
2664       return NULL;
2665       }
2666
2667     break;
2668
2669     /* Various "encrypted" comparisons. If the second string starts with
2670     "{" then an encryption type is given. Default to crypt() or crypt16()
2671     (build-time choice). */
2672     /* }-for-text-editors */
2673
2674     case ECOND_CRYPTEQ:
2675     #ifndef SUPPORT_CRYPTEQ
2676     goto COND_FAILED_NOT_COMPILED;
2677     #else
2678     if (strncmpic(sub[1], US"{md5}", 5) == 0)
2679       {
2680       int sublen = Ustrlen(sub[1]+5);
2681       md5 base;
2682       uschar digest[16];
2683
2684       md5_start(&base);
2685       md5_end(&base, (uschar *)sub[0], Ustrlen(sub[0]), digest);
2686
2687       /* If the length that we are comparing against is 24, the MD5 digest
2688       is expressed as a base64 string. This is the way LDAP does it. However,
2689       some other software uses a straightforward hex representation. We assume
2690       this if the length is 32. Other lengths fail. */
2691
2692       if (sublen == 24)
2693         {
2694         uschar *coded = auth_b64encode((uschar *)digest, 16);
2695         DEBUG(D_auth) debug_printf("crypteq: using MD5+B64 hashing\n"
2696           "  subject=%s\n  crypted=%s\n", coded, sub[1]+5);
2697         tempcond = (Ustrcmp(coded, sub[1]+5) == 0);
2698         }
2699       else if (sublen == 32)
2700         {
2701         int i;
2702         uschar coded[36];
2703         for (i = 0; i < 16; i++) sprintf(CS (coded+2*i), "%02X", digest[i]);
2704         coded[32] = 0;
2705         DEBUG(D_auth) debug_printf("crypteq: using MD5+hex hashing\n"
2706           "  subject=%s\n  crypted=%s\n", coded, sub[1]+5);
2707         tempcond = (strcmpic(coded, sub[1]+5) == 0);
2708         }
2709       else
2710         {
2711         DEBUG(D_auth) debug_printf("crypteq: length for MD5 not 24 or 32: "
2712           "fail\n  crypted=%s\n", sub[1]+5);
2713         tempcond = FALSE;
2714         }
2715       }
2716
2717     else if (strncmpic(sub[1], US"{sha1}", 6) == 0)
2718       {
2719       int sublen = Ustrlen(sub[1]+6);
2720       sha1 base;
2721       uschar digest[20];
2722
2723       sha1_start(&base);
2724       sha1_end(&base, (uschar *)sub[0], Ustrlen(sub[0]), digest);
2725
2726       /* If the length that we are comparing against is 28, assume the SHA1
2727       digest is expressed as a base64 string. If the length is 40, assume a
2728       straightforward hex representation. Other lengths fail. */
2729
2730       if (sublen == 28)
2731         {
2732         uschar *coded = auth_b64encode((uschar *)digest, 20);
2733         DEBUG(D_auth) debug_printf("crypteq: using SHA1+B64 hashing\n"
2734           "  subject=%s\n  crypted=%s\n", coded, sub[1]+6);
2735         tempcond = (Ustrcmp(coded, sub[1]+6) == 0);
2736         }
2737       else if (sublen == 40)
2738         {
2739         int i;
2740         uschar coded[44];
2741         for (i = 0; i < 20; i++) sprintf(CS (coded+2*i), "%02X", digest[i]);
2742         coded[40] = 0;
2743         DEBUG(D_auth) debug_printf("crypteq: using SHA1+hex hashing\n"
2744           "  subject=%s\n  crypted=%s\n", coded, sub[1]+6);
2745         tempcond = (strcmpic(coded, sub[1]+6) == 0);
2746         }
2747       else
2748         {
2749         DEBUG(D_auth) debug_printf("crypteq: length for SHA-1 not 28 or 40: "
2750           "fail\n  crypted=%s\n", sub[1]+6);
2751         tempcond = FALSE;
2752         }
2753       }
2754
2755     else   /* {crypt} or {crypt16} and non-{ at start */
2756            /* }-for-text-editors */
2757       {
2758       int which = 0;
2759       uschar *coded;
2760
2761       if (strncmpic(sub[1], US"{crypt}", 7) == 0)
2762         {
2763         sub[1] += 7;
2764         which = 1;
2765         }
2766       else if (strncmpic(sub[1], US"{crypt16}", 9) == 0)
2767         {
2768         sub[1] += 9;
2769         which = 2;
2770         }
2771       else if (sub[1][0] == '{')                /* }-for-text-editors */
2772         {
2773         expand_string_message = string_sprintf("unknown encryption mechanism "
2774           "in \"%s\"", sub[1]);
2775         return NULL;
2776         }
2777
2778       switch(which)
2779         {
2780         case 0:  coded = US DEFAULT_CRYPT(CS sub[0], CS sub[1]); break;
2781         case 1:  coded = US crypt(CS sub[0], CS sub[1]); break;
2782         default: coded = US crypt16(CS sub[0], CS sub[1]); break;
2783         }
2784
2785       #define STR(s) # s
2786       #define XSTR(s) STR(s)
2787       DEBUG(D_auth) debug_printf("crypteq: using %s()\n"
2788         "  subject=%s\n  crypted=%s\n",
2789         (which == 0)? XSTR(DEFAULT_CRYPT) : (which == 1)? "crypt" : "crypt16",
2790         coded, sub[1]);
2791       #undef STR
2792       #undef XSTR
2793
2794       /* If the encrypted string contains fewer than two characters (for the
2795       salt), force failure. Otherwise we get false positives: with an empty
2796       string the yield of crypt() is an empty string! */
2797
2798       tempcond = (Ustrlen(sub[1]) < 2)? FALSE :
2799         (Ustrcmp(coded, sub[1]) == 0);
2800       }
2801     break;
2802     #endif  /* SUPPORT_CRYPTEQ */
2803
2804     case ECOND_INLIST:
2805     case ECOND_INLISTI:
2806       {
2807       const uschar * list = sub[1];
2808       int sep = 0;
2809       uschar *save_iterate_item = iterate_item;
2810       int (*compare)(const uschar *, const uschar *);
2811
2812       DEBUG(D_expand) debug_printf("condition: %s\n", name);
2813
2814       tempcond = FALSE;
2815       compare = cond_type == ECOND_INLISTI
2816         ? strcmpic : (int (*)(const uschar *, const uschar *)) strcmp;
2817
2818       while ((iterate_item = string_nextinlist(&list, &sep, NULL, 0)))
2819         if (compare(sub[0], iterate_item) == 0)
2820           {
2821           tempcond = TRUE;
2822           break;
2823           }
2824       iterate_item = save_iterate_item;
2825       }
2826
2827     }   /* Switch for comparison conditions */
2828
2829   *yield = tempcond == testfor;
2830   return s;    /* End of comparison conditions */
2831
2832
2833   /* and/or: computes logical and/or of several conditions */
2834
2835   case ECOND_AND:
2836   case ECOND_OR:
2837   subcondptr = (yield == NULL)? NULL : &tempcond;
2838   combined_cond = (cond_type == ECOND_AND);
2839
2840   while (isspace(*s)) s++;
2841   if (*s++ != '{') goto COND_FAILED_CURLY_START;        /* }-for-text-editors */
2842
2843   for (;;)
2844     {
2845     while (isspace(*s)) s++;
2846     /* {-for-text-editors */
2847     if (*s == '}') break;
2848     if (*s != '{')                                      /* }-for-text-editors */
2849       {
2850       expand_string_message = string_sprintf("each subcondition "
2851         "inside an \"%s{...}\" condition must be in its own {}", name);
2852       return NULL;
2853       }
2854
2855     if (!(s = eval_condition(s+1, resetok, subcondptr)))
2856       {
2857       expand_string_message = string_sprintf("%s inside \"%s{...}\" condition",
2858         expand_string_message, name);
2859       return NULL;
2860       }
2861     while (isspace(*s)) s++;
2862
2863     /* {-for-text-editors */
2864     if (*s++ != '}')
2865       {
2866       /* {-for-text-editors */
2867       expand_string_message = string_sprintf("missing } at end of condition "
2868         "inside \"%s\" group", name);
2869       return NULL;
2870       }
2871
2872     if (yield != NULL)
2873       {
2874       if (cond_type == ECOND_AND)
2875         {
2876         combined_cond &= tempcond;
2877         if (!combined_cond) subcondptr = NULL;  /* once false, don't */
2878         }                                       /* evaluate any more */
2879       else
2880         {
2881         combined_cond |= tempcond;
2882         if (combined_cond) subcondptr = NULL;   /* once true, don't */
2883         }                                       /* evaluate any more */
2884       }
2885     }
2886
2887   if (yield != NULL) *yield = (combined_cond == testfor);
2888   return ++s;
2889
2890
2891   /* forall/forany: iterates a condition with different values */
2892
2893   case ECOND_FORALL:
2894   case ECOND_FORANY:
2895     {
2896     const uschar * list;
2897     int sep = 0;
2898     uschar *save_iterate_item = iterate_item;
2899
2900     DEBUG(D_expand) debug_printf("condition: %s\n", name);
2901
2902     while (isspace(*s)) s++;
2903     if (*s++ != '{') goto COND_FAILED_CURLY_START;      /* }-for-text-editors */
2904     sub[0] = expand_string_internal(s, TRUE, &s, (yield == NULL), TRUE, resetok);
2905     if (sub[0] == NULL) return NULL;
2906     /* {-for-text-editors */
2907     if (*s++ != '}') goto COND_FAILED_CURLY_END;
2908
2909     while (isspace(*s)) s++;
2910     if (*s++ != '{') goto COND_FAILED_CURLY_START;      /* }-for-text-editors */
2911
2912     sub[1] = s;
2913
2914     /* Call eval_condition once, with result discarded (as if scanning a
2915     "false" part). This allows us to find the end of the condition, because if
2916     the list it empty, we won't actually evaluate the condition for real. */
2917
2918     if (!(s = eval_condition(sub[1], resetok, NULL)))
2919       {
2920       expand_string_message = string_sprintf("%s inside \"%s\" condition",
2921         expand_string_message, name);
2922       return NULL;
2923       }
2924     while (isspace(*s)) s++;
2925
2926     /* {-for-text-editors */
2927     if (*s++ != '}')
2928       {
2929       /* {-for-text-editors */
2930       expand_string_message = string_sprintf("missing } at end of condition "
2931         "inside \"%s\"", name);
2932       return NULL;
2933       }
2934
2935     if (yield != NULL) *yield = !testfor;
2936     list = sub[0];
2937     while ((iterate_item = string_nextinlist(&list, &sep, NULL, 0)) != NULL)
2938       {
2939       DEBUG(D_expand) debug_printf("%s: $item = \"%s\"\n", name, iterate_item);
2940       if (!eval_condition(sub[1], resetok, &tempcond))
2941         {
2942         expand_string_message = string_sprintf("%s inside \"%s\" condition",
2943           expand_string_message, name);
2944         iterate_item = save_iterate_item;
2945         return NULL;
2946         }
2947       DEBUG(D_expand) debug_printf("%s: condition evaluated to %s\n", name,
2948         tempcond? "true":"false");
2949
2950       if (yield != NULL) *yield = (tempcond == testfor);
2951       if (tempcond == (cond_type == ECOND_FORANY)) break;
2952       }
2953
2954     iterate_item = save_iterate_item;
2955     return s;
2956     }
2957
2958
2959   /* The bool{} expansion condition maps a string to boolean.
2960   The values supported should match those supported by the ACL condition
2961   (acl.c, ACLC_CONDITION) so that we keep to a minimum the different ideas
2962   of true/false.  Note that Router "condition" rules have a different
2963   interpretation, where general data can be used and only a few values
2964   map to FALSE.
2965   Note that readconf.c boolean matching, for boolean configuration options,
2966   only matches true/yes/false/no.
2967   The bool_lax{} condition matches the Router logic, which is much more
2968   liberal. */
2969   case ECOND_BOOL:
2970   case ECOND_BOOL_LAX:
2971     {
2972     uschar *sub_arg[1];
2973     uschar *t, *t2;
2974     uschar *ourname;
2975     size_t len;
2976     BOOL boolvalue = FALSE;
2977     while (isspace(*s)) s++;
2978     if (*s != '{') goto COND_FAILED_CURLY_START;        /* }-for-text-editors */
2979     ourname = cond_type == ECOND_BOOL_LAX ? US"bool_lax" : US"bool";
2980     switch(read_subs(sub_arg, 1, 1, &s, yield == NULL, FALSE, ourname, resetok))
2981       {
2982       case 1: expand_string_message = string_sprintf(
2983                   "too few arguments or bracketing error for %s",
2984                   ourname);
2985       /*FALLTHROUGH*/
2986       case 2:
2987       case 3: return NULL;
2988       }
2989     t = sub_arg[0];
2990     while (isspace(*t)) t++;
2991     len = Ustrlen(t);
2992     if (len)
2993       {
2994       /* trailing whitespace: seems like a good idea to ignore it too */
2995       t2 = t + len - 1;
2996       while (isspace(*t2)) t2--;
2997       if (t2 != (t + len))
2998         {
2999         *++t2 = '\0';
3000         len = t2 - t;
3001         }
3002       }
3003     DEBUG(D_expand)
3004       debug_printf("considering %s: %s\n", ourname, len ? t : US"<empty>");
3005     /* logic for the lax case from expand_check_condition(), which also does
3006     expands, and the logic is both short and stable enough that there should
3007     be no maintenance burden from replicating it. */
3008     if (len == 0)
3009       boolvalue = FALSE;
3010     else if (*t == '-'
3011              ? Ustrspn(t+1, "0123456789") == len-1
3012              : Ustrspn(t,   "0123456789") == len)
3013       {
3014       boolvalue = (Uatoi(t) == 0) ? FALSE : TRUE;
3015       /* expand_check_condition only does a literal string "0" check */
3016       if ((cond_type == ECOND_BOOL_LAX) && (len > 1))
3017         boolvalue = TRUE;
3018       }
3019     else if (strcmpic(t, US"true") == 0 || strcmpic(t, US"yes") == 0)
3020       boolvalue = TRUE;
3021     else if (strcmpic(t, US"false") == 0 || strcmpic(t, US"no") == 0)
3022       boolvalue = FALSE;
3023     else if (cond_type == ECOND_BOOL_LAX)
3024       boolvalue = TRUE;
3025     else
3026       {
3027       expand_string_message = string_sprintf("unrecognised boolean "
3028        "value \"%s\"", t);
3029       return NULL;
3030       }
3031     if (yield != NULL) *yield = (boolvalue == testfor);
3032     return s;
3033     }
3034
3035   /* Unknown condition */
3036
3037   default:
3038   expand_string_message = string_sprintf("unknown condition \"%s\"", name);
3039   return NULL;
3040   }   /* End switch on condition type */
3041
3042 /* Missing braces at start and end of data */
3043
3044 COND_FAILED_CURLY_START:
3045 expand_string_message = string_sprintf("missing { after \"%s\"", name);
3046 return NULL;
3047
3048 COND_FAILED_CURLY_END:
3049 expand_string_message = string_sprintf("missing } at end of \"%s\" condition",
3050   name);
3051 return NULL;
3052
3053 /* A condition requires code that is not compiled */
3054
3055 #if !defined(SUPPORT_PAM) || !defined(RADIUS_CONFIG_FILE) || \
3056     !defined(LOOKUP_LDAP) || !defined(CYRUS_PWCHECK_SOCKET) || \
3057     !defined(SUPPORT_CRYPTEQ) || !defined(CYRUS_SASLAUTHD_SOCKET)
3058 COND_FAILED_NOT_COMPILED:
3059 expand_string_message = string_sprintf("support for \"%s\" not compiled",
3060   name);
3061 return NULL;
3062 #endif
3063 }
3064
3065
3066
3067
3068 /*************************************************
3069 *          Save numerical variables              *
3070 *************************************************/
3071
3072 /* This function is called from items such as "if" that want to preserve and
3073 restore the numbered variables.
3074
3075 Arguments:
3076   save_expand_string    points to an array of pointers to set
3077   save_expand_nlength   points to an array of ints for the lengths
3078
3079 Returns:                the value of expand max to save
3080 */
3081
3082 static int
3083 save_expand_strings(uschar **save_expand_nstring, int *save_expand_nlength)
3084 {
3085 int i;
3086 for (i = 0; i <= expand_nmax; i++)
3087   {
3088   save_expand_nstring[i] = expand_nstring[i];
3089   save_expand_nlength[i] = expand_nlength[i];
3090   }
3091 return expand_nmax;
3092 }
3093
3094
3095
3096 /*************************************************
3097 *           Restore numerical variables          *
3098 *************************************************/
3099
3100 /* This function restored saved values of numerical strings.
3101
3102 Arguments:
3103   save_expand_nmax      the number of strings to restore
3104   save_expand_string    points to an array of pointers
3105   save_expand_nlength   points to an array of ints
3106
3107 Returns:                nothing
3108 */
3109
3110 static void
3111 restore_expand_strings(int save_expand_nmax, uschar **save_expand_nstring,
3112   int *save_expand_nlength)
3113 {
3114 int i;
3115 expand_nmax = save_expand_nmax;
3116 for (i = 0; i <= expand_nmax; i++)
3117   {
3118   expand_nstring[i] = save_expand_nstring[i];
3119   expand_nlength[i] = save_expand_nlength[i];
3120   }
3121 }
3122
3123
3124
3125
3126
3127 /*************************************************
3128 *            Handle yes/no substrings            *
3129 *************************************************/
3130
3131 /* This function is used by ${if}, ${lookup} and ${extract} to handle the
3132 alternative substrings that depend on whether or not the condition was true,
3133 or the lookup or extraction succeeded. The substrings always have to be
3134 expanded, to check their syntax, but "skipping" is set when the result is not
3135 needed - this avoids unnecessary nested lookups.
3136
3137 Arguments:
3138   skipping       TRUE if we were skipping when this item was reached
3139   yes            TRUE if the first string is to be used, else use the second
3140   save_lookup    a value to put back into lookup_value before the 2nd expansion
3141   sptr           points to the input string pointer
3142   yieldptr       points to the output string pointer
3143   sizeptr        points to the output string size
3144   ptrptr         points to the output string pointer
3145   type           "lookup" or "if" or "extract" or "run", for error message
3146   resetok        if not NULL, pointer to flag - write FALSE if unsafe to reset
3147                 the store.
3148
3149 Returns:         0 OK; lookup_value has been reset to save_lookup
3150                  1 expansion failed
3151                  2 expansion failed because of bracketing error
3152 */
3153
3154 static int
3155 process_yesno(BOOL skipping, BOOL yes, uschar *save_lookup, const uschar **sptr,
3156   uschar **yieldptr, int *sizeptr, int *ptrptr, uschar *type, BOOL *resetok)
3157 {
3158 int rc = 0;
3159 const uschar *s = *sptr;    /* Local value */
3160 uschar *sub1, *sub2;
3161
3162 /* If there are no following strings, we substitute the contents of $value for
3163 lookups and for extractions in the success case. For the ${if item, the string
3164 "true" is substituted. In the fail case, nothing is substituted for all three
3165 items. */
3166
3167 while (isspace(*s)) s++;
3168 if (*s == '}')
3169   {
3170   if (type[0] == 'i')
3171     {
3172     if (yes) *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, US"true", 4);
3173     }
3174   else
3175     {
3176     if (yes && lookup_value != NULL)
3177       *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, lookup_value,
3178         Ustrlen(lookup_value));
3179     lookup_value = save_lookup;
3180     }
3181   s++;
3182   goto RETURN;
3183   }
3184
3185 /* The first following string must be braced. */
3186
3187 if (*s++ != '{') goto FAILED_CURLY;
3188
3189 /* Expand the first substring. Forced failures are noticed only if we actually
3190 want this string. Set skipping in the call in the fail case (this will always
3191 be the case if we were already skipping). */
3192
3193 sub1 = expand_string_internal(s, TRUE, &s, !yes, TRUE, resetok);
3194 if (sub1 == NULL && (yes || !expand_string_forcedfail)) goto FAILED;
3195 expand_string_forcedfail = FALSE;
3196 if (*s++ != '}') goto FAILED_CURLY;
3197
3198 /* If we want the first string, add it to the output */
3199
3200 if (yes)
3201   *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, sub1, Ustrlen(sub1));
3202
3203 /* If this is called from a lookup or an extract, we want to restore $value to
3204 what it was at the start of the item, so that it has this value during the
3205 second string expansion. For the call from "if" or "run" to this function,
3206 save_lookup is set to lookup_value, so that this statement does nothing. */
3207
3208 lookup_value = save_lookup;
3209
3210 /* There now follows either another substring, or "fail", or nothing. This
3211 time, forced failures are noticed only if we want the second string. We must
3212 set skipping in the nested call if we don't want this string, or if we were
3213 already skipping. */
3214
3215 while (isspace(*s)) s++;
3216 if (*s == '{')
3217   {
3218   sub2 = expand_string_internal(s+1, TRUE, &s, yes || skipping, TRUE, resetok);
3219   if (sub2 == NULL && (!yes || !expand_string_forcedfail)) goto FAILED;
3220   expand_string_forcedfail = FALSE;
3221   if (*s++ != '}') goto FAILED_CURLY;
3222
3223   /* If we want the second string, add it to the output */
3224
3225   if (!yes)
3226     *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, sub2, Ustrlen(sub2));
3227   }
3228
3229 /* If there is no second string, but the word "fail" is present when the use of
3230 the second string is wanted, set a flag indicating it was a forced failure
3231 rather than a syntactic error. Swallow the terminating } in case this is nested
3232 inside another lookup or if or extract. */
3233
3234 else if (*s != '}')
3235   {
3236   uschar name[256];
3237   /* deconst cast ok here as source is s anyway */
3238   s = US read_name(name, sizeof(name), s, US"_");
3239   if (Ustrcmp(name, "fail") == 0)
3240     {
3241     if (!yes && !skipping)
3242       {
3243       while (isspace(*s)) s++;
3244       if (*s++ != '}') goto FAILED_CURLY;
3245       expand_string_message =
3246         string_sprintf("\"%s\" failed and \"fail\" requested", type);
3247       expand_string_forcedfail = TRUE;
3248       goto FAILED;
3249       }
3250     }
3251   else
3252     {
3253     expand_string_message =
3254       string_sprintf("syntax error in \"%s\" item - \"fail\" expected", type);
3255     goto FAILED;
3256     }
3257   }
3258
3259 /* All we have to do now is to check on the final closing brace. */
3260
3261 while (isspace(*s)) s++;
3262 if (*s++ == '}') goto RETURN;
3263
3264 /* Get here if there is a bracketing failure */
3265
3266 FAILED_CURLY:
3267 rc++;
3268
3269 /* Get here for other failures */
3270
3271 FAILED:
3272 rc++;
3273
3274 /* Update the input pointer value before returning */
3275
3276 RETURN:
3277 *sptr = s;
3278 return rc;
3279 }
3280
3281
3282
3283
3284 /*************************************************
3285 *    Handle MD5 or SHA-1 computation for HMAC    *
3286 *************************************************/
3287
3288 /* These are some wrapping functions that enable the HMAC code to be a bit
3289 cleaner. A good compiler will spot the tail recursion.
3290
3291 Arguments:
3292   type         HMAC_MD5 or HMAC_SHA1
3293   remaining    are as for the cryptographic hash functions
3294
3295 Returns:       nothing
3296 */
3297
3298 static void
3299 chash_start(int type, void *base)
3300 {
3301 if (type == HMAC_MD5)
3302   md5_start((md5 *)base);
3303 else
3304   sha1_start((sha1 *)base);
3305 }
3306
3307 static void
3308 chash_mid(int type, void *base, uschar *string)
3309 {
3310 if (type == HMAC_MD5)
3311   md5_mid((md5 *)base, string);
3312 else
3313   sha1_mid((sha1 *)base, string);
3314 }
3315
3316 static void
3317 chash_end(int type, void *base, uschar *string, int length, uschar *digest)
3318 {
3319 if (type == HMAC_MD5)
3320   md5_end((md5 *)base, string, length, digest);
3321 else
3322   sha1_end((sha1 *)base, string, length, digest);
3323 }
3324
3325
3326
3327
3328
3329 /********************************************************
3330 * prvs: Get last three digits of days since Jan 1, 1970 *
3331 ********************************************************/
3332
3333 /* This is needed to implement the "prvs" BATV reverse
3334    path signing scheme
3335
3336 Argument: integer "days" offset to add or substract to
3337           or from the current number of days.
3338
3339 Returns:  pointer to string containing the last three
3340           digits of the number of days since Jan 1, 1970,
3341           modified by the offset argument, NULL if there
3342           was an error in the conversion.
3343
3344 */
3345
3346 static uschar *
3347 prvs_daystamp(int day_offset)
3348 {
3349 uschar *days = store_get(32);                /* Need at least 24 for cases */
3350 (void)string_format(days, 32, TIME_T_FMT,    /* where TIME_T_FMT is %lld */
3351   (time(NULL) + day_offset*86400)/86400);
3352 return (Ustrlen(days) >= 3) ? &days[Ustrlen(days)-3] : US"100";
3353 }
3354
3355
3356
3357 /********************************************************
3358 *   prvs: perform HMAC-SHA1 computation of prvs bits    *
3359 ********************************************************/
3360
3361 /* This is needed to implement the "prvs" BATV reverse
3362    path signing scheme
3363
3364 Arguments:
3365   address RFC2821 Address to use
3366       key The k