src/src/expand.c

   1 /*************************************************
   2 *     Exim - an Internet mail transport agent    *
   3 *************************************************/
   4
   5 /* Copyright (c) University of Cambridge 1995 - 2012 */
   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(uschar *, BOOL, uschar **, BOOL, BOOL);
  17
  18 #ifdef STAND_ALONE
  19 #ifndef SUPPORT_CRYPTEQ
  20 #define SUPPORT_CRYPTEQ
  21 #endif
  22 #endif
  23
  24 #ifdef LOOKUP_LDAP
  25 #include "lookups/ldap.h"
  26 #endif
  27
  28 #ifdef SUPPORT_CRYPTEQ
  29 #ifdef CRYPT_H
  30 #include <crypt.h>
  31 #endif
  32 #ifndef HAVE_CRYPT16
  33 extern char* crypt16(char*, char*);
  34 #endif
  35 #endif
  36
  37 /* The handling of crypt16() is a mess. I will record below the analysis of the
  38 mess that was sent to me. We decided, however, to make changing this very low
  39 priority, because in practice people are moving away from the crypt()
  40 algorithms nowadays, so it doesn't seem worth it.
  41
  42 <quote>
  43 There is an algorithm named "crypt16" in Ultrix and Tru64.  It crypts
  44 the first 8 characters of the password using a 20-round version of crypt
  45 (standard crypt does 25 rounds).  It then crypts the next 8 characters,
  46 or an empty block if the password is less than 9 characters, using a
  47 20-round version of crypt and the same salt as was used for the first
  48 block.  Charaters after the first 16 are ignored.  It always generates
  49 a 16-byte hash, which is expressed together with the salt as a string
  50 of 24 base 64 digits.  Here are some links to peruse:
  51
  52         http://cvs.pld.org.pl/pam/pamcrypt/crypt16.c?rev=1.2
  53         http://seclists.org/bugtraq/1999/Mar/0076.html
  54
  55 There's a different algorithm named "bigcrypt" in HP-UX, Digital Unix,
  56 and OSF/1.  This is the same as the standard crypt if given a password
  57 of 8 characters or less.  If given more, it first does the same as crypt
  58 using the first 8 characters, then crypts the next 8 (the 9th to 16th)
  59 using as salt the first two base 64 digits from the first hash block.
  60 If the password is more than 16 characters then it crypts the 17th to 24th
  61 characters using as salt the first two base 64 digits from the second hash
  62 block.  And so on: I've seen references to it cutting off the password at
  63 40 characters (5 blocks), 80 (10 blocks), or 128 (16 blocks).  Some links:
  64
  65         http://cvs.pld.org.pl/pam/pamcrypt/bigcrypt.c?rev=1.2
  66         http://seclists.org/bugtraq/1999/Mar/0109.html
  67         http://h30097.www3.hp.com/docs/base_doc/DOCUMENTATION/HTML/AA-Q0R2D-
  68              TET1_html/sec.c222.html#no_id_208
  69
  70 Exim has something it calls "crypt16".  It will either use a native
  71 crypt16 or its own implementation.  A native crypt16 will presumably
  72 be the one that I called "crypt16" above.  The internal "crypt16"
  73 function, however, is a two-block-maximum implementation of what I called
  74 "bigcrypt".  The documentation matches the internal code.
  75
  76 I suspect that whoever did the "crypt16" stuff for Exim didn't realise
  77 that crypt16 and bigcrypt were different things.
  78
  79 Exim uses the LDAP-style scheme identifier "{crypt16}" to refer
  80 to whatever it is using under that name.  This unfortunately sets a
  81 precedent for using "{crypt16}" to identify two incompatible algorithms
  82 whose output can't be distinguished.  With "{crypt16}" thus rendered
  83 ambiguous, I suggest you deprecate it and invent two new identifiers
  84 for the two algorithms.
  85
  86 Both crypt16 and bigcrypt are very poor algorithms, btw.  Hashing parts
  87 of the password separately means they can be cracked separately, so
  88 the double-length hash only doubles the cracking effort instead of
  89 squaring it.  I recommend salted SHA-1 ({SSHA}), or the Blowfish-based
  90 bcrypt ({CRYPT}$2a$).
  91 </quote>
  92 */
  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"dlfunc",
 107   US"extract",
 108   US"filter",
 109   US"hash",
 110   US"hmac",
 111   US"if",
 112   US"length",
 113   US"lookup",
 114   US"map",
 115   US"nhash",
 116   US"perl",
 117   US"prvs",
 118   US"prvscheck",
 119   US"readfile",
 120   US"readsocket",
 121   US"reduce",
 122   US"run",
 123   US"sg",
 124   US"substr",
 125   US"tr" };
 126
 127 enum {
 128   EITEM_ACL,
 129   EITEM_DLFUNC,
 130   EITEM_EXTRACT,
 131   EITEM_FILTER,
 132   EITEM_HASH,
 133   EITEM_HMAC,
 134   EITEM_IF,
 135   EITEM_LENGTH,
 136   EITEM_LOOKUP,
 137   EITEM_MAP,
 138   EITEM_NHASH,
 139   EITEM_PERL,
 140   EITEM_PRVS,
 141   EITEM_PRVSCHECK,
 142   EITEM_READFILE,
 143   EITEM_READSOCK,
 144   EITEM_REDUCE,
 145   EITEM_RUN,
 146   EITEM_SG,
 147   EITEM_SUBSTR,
 148   EITEM_TR };
 149
 150 /* Tables of operator names, and corresponding switch numbers. The names must be
 151 in alphabetical order. There are two tables, because underscore is used in some
 152 cases to introduce arguments, whereas for other it is part of the name. This is
 153 an historical mis-design. */
 154
 155 static uschar *op_table_underscore[] = {
 156   US"from_utf8",
 157   US"local_part",
 158   US"quote_local_part",
 159   US"reverse_ip",
 160   US"time_eval",
 161   US"time_interval"};
 162
 163 enum {
 164   EOP_FROM_UTF8,
 165   EOP_LOCAL_PART,
 166   EOP_QUOTE_LOCAL_PART,
 167   EOP_REVERSE_IP,
 168   EOP_TIME_EVAL,
 169   EOP_TIME_INTERVAL };
 170
 171 static uschar *op_table_main[] = {
 172   US"address",
 173   US"addresses",
 174   US"base62",
 175   US"base62d",
 176   US"domain",
 177   US"escape",
 178   US"eval",
 179   US"eval10",
 180   US"expand",
 181   US"h",
 182   US"hash",
 183   US"hex2b64",
 184   US"hexquote",
 185   US"l",
 186   US"lc",
 187   US"length",
 188   US"listcount",
 189   US"listnamed",
 190   US"mask",
 191   US"md5",
 192   US"nh",
 193   US"nhash",
 194   US"quote",
 195   US"randint",
 196   US"rfc2047",
 197   US"rfc2047d",
 198   US"rxquote",
 199   US"s",
 200   US"sha1",
 201   US"stat",
 202   US"str2b64",
 203   US"strlen",
 204   US"substr",
 205   US"uc" };
 206
 207 enum {
 208   EOP_ADDRESS =  sizeof(op_table_underscore)/sizeof(uschar *),
 209   EOP_ADDRESSES,
 210   EOP_BASE62,
 211   EOP_BASE62D,
 212   EOP_DOMAIN,
 213   EOP_ESCAPE,
 214   EOP_EVAL,
 215   EOP_EVAL10,
 216   EOP_EXPAND,
 217   EOP_H,
 218   EOP_HASH,
 219   EOP_HEX2B64,
 220   EOP_HEXQUOTE,
 221   EOP_L,
 222   EOP_LC,
 223   EOP_LENGTH,
 224   EOP_LISTCOUNT,
 225   EOP_LISTNAMED,
 226   EOP_MASK,
 227   EOP_MD5,
 228   EOP_NH,
 229   EOP_NHASH,
 230   EOP_QUOTE,
 231   EOP_RANDINT,
 232   EOP_RFC2047,
 233   EOP_RFC2047D,
 234   EOP_RXQUOTE,
 235   EOP_S,
 236   EOP_SHA1,
 237   EOP_STAT,
 238   EOP_STR2B64,
 239   EOP_STRLEN,
 240   EOP_SUBSTR,
 241   EOP_UC };
 242
 243
 244 /* Table of condition names, and corresponding switch numbers. The names must
 245 be in alphabetical order. */
 246
 247 static uschar *cond_table[] = {
 248   US"<",
 249   US"<=",
 250   US"=",
 251   US"==",     /* Backward compatibility */
 252   US">",
 253   US">=",
 254   US"acl",
 255   US"and",
 256   US"bool",
 257   US"bool_lax",
 258   US"crypteq",
 259   US"def",
 260   US"eq",
 261   US"eqi",
 262   US"exists",
 263   US"first_delivery",
 264   US"forall",
 265   US"forany",
 266   US"ge",
 267   US"gei",
 268   US"gt",
 269   US"gti",
 270   US"inlist",
 271   US"inlisti",
 272   US"isip",
 273   US"isip4",
 274   US"isip6",
 275   US"ldapauth",
 276   US"le",
 277   US"lei",
 278   US"lt",
 279   US"lti",
 280   US"match",
 281   US"match_address",
 282   US"match_domain",
 283   US"match_ip",
 284   US"match_local_part",
 285   US"or",
 286   US"pam",
 287   US"pwcheck",
 288   US"queue_running",
 289   US"radius",
 290   US"saslauthd"
 291 };
 292
 293 enum {
 294   ECOND_NUM_L,
 295   ECOND_NUM_LE,
 296   ECOND_NUM_E,
 297   ECOND_NUM_EE,
 298   ECOND_NUM_G,
 299   ECOND_NUM_GE,
 300   ECOND_ACL,
 301   ECOND_AND,
 302   ECOND_BOOL,
 303   ECOND_BOOL_LAX,
 304   ECOND_CRYPTEQ,
 305   ECOND_DEF,
 306   ECOND_STR_EQ,
 307   ECOND_STR_EQI,
 308   ECOND_EXISTS,
 309   ECOND_FIRST_DELIVERY,
 310   ECOND_FORALL,
 311   ECOND_FORANY,
 312   ECOND_STR_GE,
 313   ECOND_STR_GEI,
 314   ECOND_STR_GT,
 315   ECOND_STR_GTI,
 316   ECOND_INLIST,
 317   ECOND_INLISTI,
 318   ECOND_ISIP,
 319   ECOND_ISIP4,
 320   ECOND_ISIP6,
 321   ECOND_LDAPAUTH,
 322   ECOND_STR_LE,
 323   ECOND_STR_LEI,
 324   ECOND_STR_LT,
 325   ECOND_STR_LTI,
 326   ECOND_MATCH,
 327   ECOND_MATCH_ADDRESS,
 328   ECOND_MATCH_DOMAIN,
 329   ECOND_MATCH_IP,
 330   ECOND_MATCH_LOCAL_PART,
 331   ECOND_OR,
 332   ECOND_PAM,
 333   ECOND_PWCHECK,
 334   ECOND_QUEUE_RUNNING,
 335   ECOND_RADIUS,
 336   ECOND_SASLAUTHD
 337 };
 338
 339
 340 /* Type for main variable table */
 341
 342 typedef struct {
 343   const char *name;
 344   int         type;
 345   void       *value;
 346 } var_entry;
 347
 348 /* Type for entries pointing to address/length pairs. Not currently
 349 in use. */
 350
 351 typedef struct {
 352   uschar **address;
 353   int  *length;
 354 } alblock;
 355
 356 /* Types of table entry */
 357
 358 enum {
 359   vtype_int,            /* value is address of int */
 360   vtype_filter_int,     /* ditto, but recognized only when filtering */
 361   vtype_ino,            /* value is address of ino_t (not always an int) */
 362   vtype_uid,            /* value is address of uid_t (not always an int) */
 363   vtype_gid,            /* value is address of gid_t (not always an int) */
 364   vtype_bool,           /* value is address of bool */
 365   vtype_stringptr,      /* value is address of pointer to string */
 366   vtype_msgbody,        /* as stringptr, but read when first required */
 367   vtype_msgbody_end,    /* ditto, the end of the message */
 368   vtype_msgheaders,     /* the message's headers, processed */
 369   vtype_msgheaders_raw, /* the message's headers, unprocessed */
 370   vtype_localpart,      /* extract local part from string */
 371   vtype_domain,         /* extract domain from string */
 372   vtype_string_func,    /* value is string returned by given function */
 373   vtype_todbsdin,       /* value not used; generate BSD inbox tod */
 374   vtype_tode,           /* value not used; generate tod in epoch format */
 375   vtype_todel,          /* value not used; generate tod in epoch/usec format */
 376   vtype_todf,           /* value not used; generate full tod */
 377   vtype_todl,           /* value not used; generate log tod */
 378   vtype_todlf,          /* value not used; generate log file datestamp tod */
 379   vtype_todzone,        /* value not used; generate time zone only */
 380   vtype_todzulu,        /* value not used; generate zulu tod */
 381   vtype_reply,          /* value not used; get reply from headers */
 382   vtype_pid,            /* value not used; result is pid */
 383   vtype_host_lookup,    /* value not used; get host name */
 384   vtype_load_avg,       /* value not used; result is int from os_getloadavg */
 385   vtype_pspace,         /* partition space; value is T/F for spool/log */
 386   vtype_pinodes         /* partition inodes; value is T/F for spool/log */
 387   #ifndef DISABLE_DKIM
 388   ,vtype_dkim           /* Lookup of value in DKIM signature */
 389   #endif
 390   };
 391
 392 static uschar * fn_recipients(void);
 393
 394 /* This table must be kept in alphabetical order. */
 395
 396 static var_entry var_table[] = {
 397   /* WARNING: Do not invent variables whose names start acl_c or acl_m because
 398      they will be confused with user-creatable ACL variables. */
 399   { "acl_arg1",            vtype_stringptr,   &acl_arg[0] },
 400   { "acl_arg2",            vtype_stringptr,   &acl_arg[1] },
 401   { "acl_arg3",            vtype_stringptr,   &acl_arg[2] },
 402   { "acl_arg4",            vtype_stringptr,   &acl_arg[3] },
 403   { "acl_arg5",            vtype_stringptr,   &acl_arg[4] },
 404   { "acl_arg6",            vtype_stringptr,   &acl_arg[5] },
 405   { "acl_arg7",            vtype_stringptr,   &acl_arg[6] },
 406   { "acl_arg8",            vtype_stringptr,   &acl_arg[7] },
 407   { "acl_arg9",            vtype_stringptr,   &acl_arg[8] },
 408   { "acl_narg",            vtype_int,         &acl_narg },
 409   { "acl_verify_message",  vtype_stringptr,   &acl_verify_message },
 410   { "address_data",        vtype_stringptr,   &deliver_address_data },
 411   { "address_file",        vtype_stringptr,   &address_file },
 412   { "address_pipe",        vtype_stringptr,   &address_pipe },
 413   { "authenticated_fail_id",vtype_stringptr,  &authenticated_fail_id },
 414   { "authenticated_id",    vtype_stringptr,   &authenticated_id },
 415   { "authenticated_sender",vtype_stringptr,   &authenticated_sender },
 416   { "authentication_failed",vtype_int,        &authentication_failed },
 417 #ifdef WITH_CONTENT_SCAN
 418   { "av_failed",           vtype_int,         &av_failed },
 419 #endif
 420 #ifdef EXPERIMENTAL_BRIGHTMAIL
 421   { "bmi_alt_location",    vtype_stringptr,   &bmi_alt_location },
 422   { "bmi_base64_tracker_verdict", vtype_stringptr, &bmi_base64_tracker_verdict },
 423   { "bmi_base64_verdict",  vtype_stringptr,   &bmi_base64_verdict },
 424   { "bmi_deliver",         vtype_int,         &bmi_deliver },
 425 #endif
 426   { "body_linecount",      vtype_int,         &body_linecount },
 427   { "body_zerocount",      vtype_int,         &body_zerocount },
 428   { "bounce_recipient",    vtype_stringptr,   &bounce_recipient },
 429   { "bounce_return_size_limit", vtype_int,    &bounce_return_size_limit },
 430   { "caller_gid",          vtype_gid,         &real_gid },
 431   { "caller_uid",          vtype_uid,         &real_uid },
 432   { "compile_date",        vtype_stringptr,   &version_date },
 433   { "compile_number",      vtype_stringptr,   &version_cnumber },
 434   { "csa_status",          vtype_stringptr,   &csa_status },
 435 #ifdef EXPERIMENTAL_DCC
 436   { "dcc_header",          vtype_stringptr,   &dcc_header },
 437   { "dcc_result",          vtype_stringptr,   &dcc_result },
 438 #endif
 439 #ifdef WITH_OLD_DEMIME
 440   { "demime_errorlevel",   vtype_int,         &demime_errorlevel },
 441   { "demime_reason",       vtype_stringptr,   &demime_reason },
 442 #endif
 443 #ifndef DISABLE_DKIM
 444   { "dkim_algo",           vtype_dkim,        (void *)DKIM_ALGO },
 445   { "dkim_bodylength",     vtype_dkim,        (void *)DKIM_BODYLENGTH },
 446   { "dkim_canon_body",     vtype_dkim,        (void *)DKIM_CANON_BODY },
 447   { "dkim_canon_headers",  vtype_dkim,        (void *)DKIM_CANON_HEADERS },
 448   { "dkim_copiedheaders",  vtype_dkim,        (void *)DKIM_COPIEDHEADERS },
 449   { "dkim_created",        vtype_dkim,        (void *)DKIM_CREATED },
 450   { "dkim_cur_signer",     vtype_stringptr,   &dkim_cur_signer },
 451   { "dkim_domain",         vtype_stringptr,   &dkim_signing_domain },
 452   { "dkim_expires",        vtype_dkim,        (void *)DKIM_EXPIRES },
 453   { "dkim_headernames",    vtype_dkim,        (void *)DKIM_HEADERNAMES },
 454   { "dkim_identity",       vtype_dkim,        (void *)DKIM_IDENTITY },
 455   { "dkim_key_granularity",vtype_dkim,        (void *)DKIM_KEY_GRANULARITY },
 456   { "dkim_key_nosubdomains",vtype_dkim,       (void *)DKIM_NOSUBDOMAINS },
 457   { "dkim_key_notes",      vtype_dkim,        (void *)DKIM_KEY_NOTES },
 458   { "dkim_key_srvtype",    vtype_dkim,        (void *)DKIM_KEY_SRVTYPE },
 459   { "dkim_key_testing",    vtype_dkim,        (void *)DKIM_KEY_TESTING },
 460   { "dkim_selector",       vtype_stringptr,   &dkim_signing_selector },
 461   { "dkim_signers",        vtype_stringptr,   &dkim_signers },
 462   { "dkim_verify_reason",  vtype_dkim,        (void *)DKIM_VERIFY_REASON },
 463   { "dkim_verify_status",  vtype_dkim,        (void *)DKIM_VERIFY_STATUS},
 464 #endif
 465 #ifdef EXPERIMENTAL_DMARC
 466   { "dmarc_ar_header",     vtype_stringptr,   &dmarc_ar_header },
 467   { "dmarc_status",        vtype_stringptr,   &dmarc_status },
 468   { "dmarc_status_text",   vtype_stringptr,   &dmarc_status_text },
 469   { "dmarc_used_domain",   vtype_stringptr,   &dmarc_used_domain },
 470 #endif
 471   { "dnslist_domain",      vtype_stringptr,   &dnslist_domain },
 472   { "dnslist_matched",     vtype_stringptr,   &dnslist_matched },
 473   { "dnslist_text",        vtype_stringptr,   &dnslist_text },
 474   { "dnslist_value",       vtype_stringptr,   &dnslist_value },
 475   { "domain",              vtype_stringptr,   &deliver_domain },
 476   { "domain_data",         vtype_stringptr,   &deliver_domain_data },
 477   { "exim_gid",            vtype_gid,         &exim_gid },
 478   { "exim_path",           vtype_stringptr,   &exim_path },
 479   { "exim_uid",            vtype_uid,         &exim_uid },
 480 #ifdef WITH_OLD_DEMIME
 481   { "found_extension",     vtype_stringptr,   &found_extension },
 482 #endif
 483   { "headers_added",       vtype_string_func, &fn_hdrs_added },
 484   { "home",                vtype_stringptr,   &deliver_home },
 485   { "host",                vtype_stringptr,   &deliver_host },
 486   { "host_address",        vtype_stringptr,   &deliver_host_address },
 487   { "host_data",           vtype_stringptr,   &host_data },
 488   { "host_lookup_deferred",vtype_int,         &host_lookup_deferred },
 489   { "host_lookup_failed",  vtype_int,         &host_lookup_failed },
 490   { "inode",               vtype_ino,         &deliver_inode },
 491   { "interface_address",   vtype_stringptr,   &interface_address },
 492   { "interface_port",      vtype_int,         &interface_port },
 493   { "item",                vtype_stringptr,   &iterate_item },
 494   #ifdef LOOKUP_LDAP
 495   { "ldap_dn",             vtype_stringptr,   &eldap_dn },
 496   #endif
 497   { "load_average",        vtype_load_avg,    NULL },
 498   { "local_part",          vtype_stringptr,   &deliver_localpart },
 499   { "local_part_data",     vtype_stringptr,   &deliver_localpart_data },
 500   { "local_part_prefix",   vtype_stringptr,   &deliver_localpart_prefix },
 501   { "local_part_suffix",   vtype_stringptr,   &deliver_localpart_suffix },
 502   { "local_scan_data",     vtype_stringptr,   &local_scan_data },
 503   { "local_user_gid",      vtype_gid,         &local_user_gid },
 504   { "local_user_uid",      vtype_uid,         &local_user_uid },
 505   { "localhost_number",    vtype_int,         &host_number },
 506   { "log_inodes",          vtype_pinodes,     (void *)FALSE },
 507   { "log_space",           vtype_pspace,      (void *)FALSE },
 508   { "mailstore_basename",  vtype_stringptr,   &mailstore_basename },
 509 #ifdef WITH_CONTENT_SCAN
 510   { "malware_name",        vtype_stringptr,   &malware_name },
 511 #endif
 512   { "max_received_linelength", vtype_int,     &max_received_linelength },
 513   { "message_age",         vtype_int,         &message_age },
 514   { "message_body",        vtype_msgbody,     &message_body },
 515   { "message_body_end",    vtype_msgbody_end, &message_body_end },
 516   { "message_body_size",   vtype_int,         &message_body_size },
 517   { "message_exim_id",     vtype_stringptr,   &message_id },
 518   { "message_headers",     vtype_msgheaders,  NULL },
 519   { "message_headers_raw", vtype_msgheaders_raw, NULL },
 520   { "message_id",          vtype_stringptr,   &message_id },
 521   { "message_linecount",   vtype_int,         &message_linecount },
 522   { "message_size",        vtype_int,         &message_size },
 523 #ifdef WITH_CONTENT_SCAN
 524   { "mime_anomaly_level",  vtype_int,         &mime_anomaly_level },
 525   { "mime_anomaly_text",   vtype_stringptr,   &mime_anomaly_text },
 526   { "mime_boundary",       vtype_stringptr,   &mime_boundary },
 527   { "mime_charset",        vtype_stringptr,   &mime_charset },
 528   { "mime_content_description", vtype_stringptr, &mime_content_description },
 529   { "mime_content_disposition", vtype_stringptr, &mime_content_disposition },
 530   { "mime_content_id",     vtype_stringptr,   &mime_content_id },
 531   { "mime_content_size",   vtype_int,         &mime_content_size },
 532   { "mime_content_transfer_encoding",vtype_stringptr, &mime_content_transfer_encoding },
 533   { "mime_content_type",   vtype_stringptr,   &mime_content_type },
 534   { "mime_decoded_filename", vtype_stringptr, &mime_decoded_filename },
 535   { "mime_filename",       vtype_stringptr,   &mime_filename },
 536   { "mime_is_coverletter", vtype_int,         &mime_is_coverletter },
 537   { "mime_is_multipart",   vtype_int,         &mime_is_multipart },
 538   { "mime_is_rfc822",      vtype_int,         &mime_is_rfc822 },
 539   { "mime_part_count",     vtype_int,         &mime_part_count },
 540 #endif
 541   { "n0",                  vtype_filter_int,  &filter_n[0] },
 542   { "n1",                  vtype_filter_int,  &filter_n[1] },
 543   { "n2",                  vtype_filter_int,  &filter_n[2] },
 544   { "n3",                  vtype_filter_int,  &filter_n[3] },
 545   { "n4",                  vtype_filter_int,  &filter_n[4] },
 546   { "n5",                  vtype_filter_int,  &filter_n[5] },
 547   { "n6",                  vtype_filter_int,  &filter_n[6] },
 548   { "n7",                  vtype_filter_int,  &filter_n[7] },
 549   { "n8",                  vtype_filter_int,  &filter_n[8] },
 550   { "n9",                  vtype_filter_int,  &filter_n[9] },
 551   { "original_domain",     vtype_stringptr,   &deliver_domain_orig },
 552   { "original_local_part", vtype_stringptr,   &deliver_localpart_orig },
 553   { "originator_gid",      vtype_gid,         &originator_gid },
 554   { "originator_uid",      vtype_uid,         &originator_uid },
 555   { "parent_domain",       vtype_stringptr,   &deliver_domain_parent },
 556   { "parent_local_part",   vtype_stringptr,   &deliver_localpart_parent },
 557   { "pid",                 vtype_pid,         NULL },
 558   { "primary_hostname",    vtype_stringptr,   &primary_hostname },
 559   { "prvscheck_address",   vtype_stringptr,   &prvscheck_address },
 560   { "prvscheck_keynum",    vtype_stringptr,   &prvscheck_keynum },
 561   { "prvscheck_result",    vtype_stringptr,   &prvscheck_result },
 562   { "qualify_domain",      vtype_stringptr,   &qualify_domain_sender },
 563   { "qualify_recipient",   vtype_stringptr,   &qualify_domain_recipient },
 564   { "rcpt_count",          vtype_int,         &rcpt_count },
 565   { "rcpt_defer_count",    vtype_int,         &rcpt_defer_count },
 566   { "rcpt_fail_count",     vtype_int,         &rcpt_fail_count },
 567   { "received_count",      vtype_int,         &received_count },
 568   { "received_for",        vtype_stringptr,   &received_for },
 569   { "received_ip_address", vtype_stringptr,   &interface_address },
 570   { "received_port",       vtype_int,         &interface_port },
 571   { "received_protocol",   vtype_stringptr,   &received_protocol },
 572   { "received_time",       vtype_int,         &received_time },
 573   { "recipient_data",      vtype_stringptr,   &recipient_data },
 574   { "recipient_verify_failure",vtype_stringptr,&recipient_verify_failure },
 575   { "recipients",          vtype_string_func, &fn_recipients },
 576   { "recipients_count",    vtype_int,         &recipients_count },
 577 #ifdef WITH_CONTENT_SCAN
 578   { "regex_match_string",  vtype_stringptr,   &regex_match_string },
 579 #endif
 580   { "reply_address",       vtype_reply,       NULL },
 581   { "return_path",         vtype_stringptr,   &return_path },
 582   { "return_size_limit",   vtype_int,         &bounce_return_size_limit },
 583   { "router_name",         vtype_stringptr,   &router_name },
 584   { "runrc",               vtype_int,         &runrc },
 585   { "self_hostname",       vtype_stringptr,   &self_hostname },
 586   { "sender_address",      vtype_stringptr,   &sender_address },
 587   { "sender_address_data", vtype_stringptr,   &sender_address_data },
 588   { "sender_address_domain", vtype_domain,    &sender_address },
 589   { "sender_address_local_part", vtype_localpart, &sender_address },
 590   { "sender_data",         vtype_stringptr,   &sender_data },
 591   { "sender_fullhost",     vtype_stringptr,   &sender_fullhost },
 592   { "sender_helo_name",    vtype_stringptr,   &sender_helo_name },
 593   { "sender_host_address", vtype_stringptr,   &sender_host_address },
 594   { "sender_host_authenticated",vtype_stringptr, &sender_host_authenticated },
 595   { "sender_host_dnssec",  vtype_bool,        &sender_host_dnssec },
 596   { "sender_host_name",    vtype_host_lookup, NULL },
 597   { "sender_host_port",    vtype_int,         &sender_host_port },
 598   { "sender_ident",        vtype_stringptr,   &sender_ident },
 599   { "sender_rate",         vtype_stringptr,   &sender_rate },
 600   { "sender_rate_limit",   vtype_stringptr,   &sender_rate_limit },
 601   { "sender_rate_period",  vtype_stringptr,   &sender_rate_period },
 602   { "sender_rcvhost",      vtype_stringptr,   &sender_rcvhost },
 603   { "sender_verify_failure",vtype_stringptr,  &sender_verify_failure },
 604   { "sending_ip_address",  vtype_stringptr,   &sending_ip_address },
 605   { "sending_port",        vtype_int,         &sending_port },
 606   { "smtp_active_hostname", vtype_stringptr,  &smtp_active_hostname },
 607   { "smtp_command",        vtype_stringptr,   &smtp_cmd_buffer },
 608   { "smtp_command_argument", vtype_stringptr, &smtp_cmd_argument },
 609   { "smtp_count_at_connection_start", vtype_int, &smtp_accept_count },
 610   { "smtp_notquit_reason", vtype_stringptr,   &smtp_notquit_reason },
 611   { "sn0",                 vtype_filter_int,  &filter_sn[0] },
 612   { "sn1",                 vtype_filter_int,  &filter_sn[1] },
 613   { "sn2",                 vtype_filter_int,  &filter_sn[2] },
 614   { "sn3",                 vtype_filter_int,  &filter_sn[3] },
 615   { "sn4",                 vtype_filter_int,  &filter_sn[4] },
 616   { "sn5",                 vtype_filter_int,  &filter_sn[5] },
 617   { "sn6",                 vtype_filter_int,  &filter_sn[6] },
 618   { "sn7",                 vtype_filter_int,  &filter_sn[7] },
 619   { "sn8",                 vtype_filter_int,  &filter_sn[8] },
 620   { "sn9",                 vtype_filter_int,  &filter_sn[9] },
 621 #ifdef WITH_CONTENT_SCAN
 622   { "spam_bar",            vtype_stringptr,   &spam_bar },
 623   { "spam_report",         vtype_stringptr,   &spam_report },
 624   { "spam_score",          vtype_stringptr,   &spam_score },
 625   { "spam_score_int",      vtype_stringptr,   &spam_score_int },
 626 #endif
 627 #ifdef EXPERIMENTAL_SPF
 628   { "spf_guess",           vtype_stringptr,   &spf_guess },
 629   { "spf_header_comment",  vtype_stringptr,   &spf_header_comment },
 630   { "spf_received",        vtype_stringptr,   &spf_received },
 631   { "spf_result",          vtype_stringptr,   &spf_result },
 632   { "spf_smtp_comment",    vtype_stringptr,   &spf_smtp_comment },
 633 #endif
 634   { "spool_directory",     vtype_stringptr,   &spool_directory },
 635   { "spool_inodes",        vtype_pinodes,     (void *)TRUE },
 636   { "spool_space",         vtype_pspace,      (void *)TRUE },
 637 #ifdef EXPERIMENTAL_SRS
 638   { "srs_db_address",      vtype_stringptr,   &srs_db_address },
 639   { "srs_db_key",          vtype_stringptr,   &srs_db_key },
 640   { "srs_orig_recipient",  vtype_stringptr,   &srs_orig_recipient },
 641   { "srs_orig_sender",     vtype_stringptr,   &srs_orig_sender },
 642   { "srs_recipient",       vtype_stringptr,   &srs_recipient },
 643   { "srs_status",          vtype_stringptr,   &srs_status },
 644 #endif
 645   { "thisaddress",         vtype_stringptr,   &filter_thisaddress },
 646
 647   /* The non-(in,out) variables are now deprecated */
 648   { "tls_bits",            vtype_int,         &tls_in.bits },
 649   { "tls_certificate_verified", vtype_int,    &tls_in.certificate_verified },
 650   { "tls_cipher",          vtype_stringptr,   &tls_in.cipher },
 651
 652   { "tls_in_bits",         vtype_int,         &tls_in.bits },
 653   { "tls_in_certificate_verified", vtype_int, &tls_in.certificate_verified },
 654   { "tls_in_cipher",       vtype_stringptr,   &tls_in.cipher },
 655   { "tls_in_peerdn",       vtype_stringptr,   &tls_in.peerdn },
 656 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
 657   { "tls_in_sni",          vtype_stringptr,   &tls_in.sni },
 658 #endif
 659   { "tls_out_bits",        vtype_int,         &tls_out.bits },
 660   { "tls_out_certificate_verified", vtype_int,&tls_out.certificate_verified },
 661   { "tls_out_cipher",      vtype_stringptr,   &tls_out.cipher },
 662   { "tls_out_peerdn",      vtype_stringptr,   &tls_out.peerdn },
 663 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
 664   { "tls_out_sni",         vtype_stringptr,   &tls_out.sni },
 665 #endif
 666
 667   { "tls_peerdn",          vtype_stringptr,   &tls_in.peerdn }, /* mind the alphabetical order! */
 668 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
 669   { "tls_sni",             vtype_stringptr,   &tls_in.sni },    /* mind the alphabetical order! */
 670 #endif
 671
 672   { "tod_bsdinbox",        vtype_todbsdin,    NULL },
 673   { "tod_epoch",           vtype_tode,        NULL },
 674   { "tod_epoch_l",         vtype_todel,       NULL },
 675   { "tod_full",            vtype_todf,        NULL },
 676   { "tod_log",             vtype_todl,        NULL },
 677   { "tod_logfile",         vtype_todlf,       NULL },
 678   { "tod_zone",            vtype_todzone,     NULL },
 679   { "tod_zulu",            vtype_todzulu,     NULL },
 680 #ifdef EXPERIMENTAL_TPDA
 681   { "tpda_defer_errno",     vtype_int,         &tpda_defer_errno },
 682   { "tpda_defer_errstr",    vtype_stringptr,   &tpda_defer_errstr },
 683   { "tpda_delivery_confirmation", vtype_stringptr,   &tpda_delivery_confirmation },
 684   { "tpda_delivery_domain", vtype_stringptr,   &tpda_delivery_domain },
 685   { "tpda_delivery_fqdn",   vtype_stringptr,   &tpda_delivery_fqdn },
 686   { "tpda_delivery_ip",     vtype_stringptr,   &tpda_delivery_ip },
 687   { "tpda_delivery_local_part",vtype_stringptr,&tpda_delivery_local_part },
 688   { "tpda_delivery_port",   vtype_int,         &tpda_delivery_port },
 689 #endif
 690   { "transport_name",      vtype_stringptr,   &transport_name },
 691   { "value",               vtype_stringptr,   &lookup_value },
 692   { "version_number",      vtype_stringptr,   &version_string },
 693   { "warn_message_delay",  vtype_stringptr,   &warnmsg_delay },
 694   { "warn_message_recipient",vtype_stringptr, &warnmsg_recipients },
 695   { "warn_message_recipients",vtype_stringptr,&warnmsg_recipients },
 696   { "warnmsg_delay",       vtype_stringptr,   &warnmsg_delay },
 697   { "warnmsg_recipient",   vtype_stringptr,   &warnmsg_recipients },
 698   { "warnmsg_recipients",  vtype_stringptr,   &warnmsg_recipients }
 699 };
 700
 701 static int var_table_size = sizeof(var_table)/sizeof(var_entry);
 702 static uschar var_buffer[256];
 703 static BOOL malformed_header;
 704
 705 /* For textual hashes */
 706
 707 static const char *hashcodes = "abcdefghijklmnopqrtsuvwxyz"
 708                                "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
 709                                "0123456789";
 710
 711 enum { HMAC_MD5, HMAC_SHA1 };
 712
 713 /* For numeric hashes */
 714
 715 static unsigned int prime[] = {
 716   2,   3,   5,   7,  11,  13,  17,  19,  23,  29,
 717  31,  37,  41,  43,  47,  53,  59,  61,  67,  71,
 718  73,  79,  83,  89,  97, 101, 103, 107, 109, 113};
 719
 720 /* For printing modes in symbolic form */
 721
 722 static uschar *mtable_normal[] =
 723   { US"---", US"--x", US"-w-", US"-wx", US"r--", US"r-x", US"rw-", US"rwx" };
 724
 725 static uschar *mtable_setid[] =
 726   { US"--S", US"--s", US"-wS", US"-ws", US"r-S", US"r-s", US"rwS", US"rws" };
 727
 728 static uschar *mtable_sticky[] =
 729   { US"--T", US"--t", US"-wT", US"-wt", US"r-T", US"r-t", US"rwT", US"rwt" };
 730
 731
 732
 733 /*************************************************
 734 *           Tables for UTF-8 support             *
 735 *************************************************/
 736
 737 /* Table of the number of extra characters, indexed by the first character
 738 masked with 0x3f. The highest number for a valid UTF-8 character is in fact
 739 0x3d. */
 740
 741 static uschar utf8_table1[] = {
 742   1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
 743   1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
 744   2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
 745   3,3,3,3,3,3,3,3,4,4,4,4,5,5,5,5 };
 746
 747 /* These are the masks for the data bits in the first byte of a character,
 748 indexed by the number of additional bytes. */
 749
 750 static int utf8_table2[] = { 0xff, 0x1f, 0x0f, 0x07, 0x03, 0x01};
 751
 752 /* Get the next UTF-8 character, advancing the pointer. */
 753
 754 #define GETUTF8INC(c, ptr) \
 755   c = *ptr++; \
 756   if ((c & 0xc0) == 0xc0) \
 757     { \
 758     int a = utf8_table1[c & 0x3f];  /* Number of additional bytes */ \
 759     int s = 6*a; \
 760     c = (c & utf8_table2[a]) << s; \
 761     while (a-- > 0) \
 762       { \
 763       s -= 6; \
 764       c |= (*ptr++ & 0x3f) << s; \
 765       } \
 766     }
 767
 768
 769 /*************************************************
 770 *           Binary chop search on a table        *
 771 *************************************************/
 772
 773 /* This is used for matching expansion items and operators.
 774
 775 Arguments:
 776   name        the name that is being sought
 777   table       the table to search
 778   table_size  the number of items in the table
 779
 780 Returns:      the offset in the table, or -1
 781 */
 782
 783 static int
 784 chop_match(uschar *name, uschar **table, int table_size)
 785 {
 786 uschar **bot = table;
 787 uschar **top = table + table_size;
 788
 789 while (top > bot)
 790   {
 791   uschar **mid = bot + (top - bot)/2;
 792   int c = Ustrcmp(name, *mid);
 793   if (c == 0) return mid - table;
 794   if (c > 0) bot = mid + 1; else top = mid;
 795   }
 796
 797 return -1;
 798 }
 799
 800
 801
 802 /*************************************************
 803 *          Check a condition string              *
 804 *************************************************/
 805
 806 /* This function is called to expand a string, and test the result for a "true"
 807 or "false" value. Failure of the expansion yields FALSE; logged unless it was a
 808 forced fail or lookup defer.
 809
 810 We used to release all store used, but this is not not safe due
 811 to ${dlfunc } and ${acl }.  In any case expand_string_internal()
 812 is reasonably careful to release what it can.
 813
 814 The actual false-value tests should be replicated for ECOND_BOOL_LAX.
 815
 816 Arguments:
 817   condition     the condition string
 818   m1            text to be incorporated in panic error
 819   m2            ditto
 820
 821 Returns:        TRUE if condition is met, FALSE if not
 822 */
 823
 824 BOOL
 825 expand_check_condition(uschar *condition, uschar *m1, uschar *m2)
 826 {
 827 int rc;
 828 uschar *ss = expand_string(condition);
 829 if (ss == NULL)
 830   {
 831   if (!expand_string_forcedfail && !search_find_defer)
 832     log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand condition \"%s\" "
 833       "for %s %s: %s", condition, m1, m2, expand_string_message);
 834   return FALSE;
 835   }
 836 rc = ss[0] != 0 && Ustrcmp(ss, "0") != 0 && strcmpic(ss, US"no") != 0 &&
 837   strcmpic(ss, US"false") != 0;
 838 return rc;
 839 }
 840
 841
 842
 843
 844 /*************************************************
 845 *        Pseudo-random number generation         *
 846 *************************************************/
 847
 848 /* Pseudo-random number generation.  The result is not "expected" to be
 849 cryptographically strong but not so weak that someone will shoot themselves
 850 in the foot using it as a nonce in some email header scheme or whatever
 851 weirdness they'll twist this into.  The result should ideally handle fork().
 852
 853 However, if we're stuck unable to provide this, then we'll fall back to
 854 appallingly bad randomness.
 855
 856 If SUPPORT_TLS is defined then this will not be used except as an emergency
 857 fallback.
 858
 859 Arguments:
 860   max       range maximum
 861 Returns     a random number in range [0, max-1]
 862 */
 863
 864 #ifdef SUPPORT_TLS
 865 # define vaguely_random_number vaguely_random_number_fallback
 866 #endif
 867 int
 868 vaguely_random_number(int max)
 869 {
 870 #ifdef SUPPORT_TLS
 871 # undef vaguely_random_number
 872 #endif
 873   static pid_t pid = 0;
 874   pid_t p2;
 875 #if defined(HAVE_SRANDOM) && !defined(HAVE_SRANDOMDEV)
 876   struct timeval tv;
 877 #endif
 878
 879   p2 = getpid();
 880   if (p2 != pid)
 881     {
 882     if (pid != 0)
 883       {
 884
 885 #ifdef HAVE_ARC4RANDOM
 886       /* cryptographically strong randomness, common on *BSD platforms, not
 887       so much elsewhere.  Alas. */
 888       arc4random_stir();
 889 #elif defined(HAVE_SRANDOM) || defined(HAVE_SRANDOMDEV)
 890 #ifdef HAVE_SRANDOMDEV
 891       /* uses random(4) for seeding */
 892       srandomdev();
 893 #else
 894       gettimeofday(&tv, NULL);
 895       srandom(tv.tv_sec | tv.tv_usec | getpid());
 896 #endif
 897 #else
 898       /* Poor randomness and no seeding here */
 899 #endif
 900
 901       }
 902     pid = p2;
 903     }
 904
 905 #ifdef HAVE_ARC4RANDOM
 906   return arc4random() % max;
 907 #elif defined(HAVE_SRANDOM) || defined(HAVE_SRANDOMDEV)
 908   return random() % max;
 909 #else
 910   /* This one returns a 16-bit number, definitely not crypto-strong */
 911   return random_number(max);
 912 #endif
 913 }
 914
 915
 916
 917
 918 /*************************************************
 919 *             Pick out a name from a string      *
 920 *************************************************/
 921
 922 /* If the name is too long, it is silently truncated.
 923
 924 Arguments:
 925   name      points to a buffer into which to put the name
 926   max       is the length of the buffer
 927   s         points to the first alphabetic character of the name
 928   extras    chars other than alphanumerics to permit
 929
 930 Returns:    pointer to the first character after the name
 931
 932 Note: The test for *s != 0 in the while loop is necessary because
 933 Ustrchr() yields non-NULL if the character is zero (which is not something
 934 I expected). */
 935
 936 static uschar *
 937 read_name(uschar *name, int max, uschar *s, uschar *extras)
 938 {
 939 int ptr = 0;
 940 while (*s != 0 && (isalnum(*s) || Ustrchr(extras, *s) != NULL))
 941   {
 942   if (ptr < max-1) name[ptr++] = *s;
 943   s++;
 944   }
 945 name[ptr] = 0;
 946 return s;
 947 }
 948
 949
 950
 951 /*************************************************
 952 *     Pick out the rest of a header name         *
 953 *************************************************/
 954
 955 /* A variable name starting $header_ (or just $h_ for those who like
 956 abbreviations) might not be the complete header name because headers can
 957 contain any printing characters in their names, except ':'. This function is
 958 called to read the rest of the name, chop h[eader]_ off the front, and put ':'
 959 on the end, if the name was terminated by white space.
 960
 961 Arguments:
 962   name      points to a buffer in which the name read so far exists
 963   max       is the length of the buffer
 964   s         points to the first character after the name so far, i.e. the
 965             first non-alphameric character after $header_xxxxx
 966
 967 Returns:    a pointer to the first character after the header name
 968 */
 969
 970 static uschar *
 971 read_header_name(uschar *name, int max, uschar *s)
 972 {
 973 int prelen = Ustrchr(name, '_') - name + 1;
 974 int ptr = Ustrlen(name) - prelen;
 975 if (ptr > 0) memmove(name, name+prelen, ptr);
 976 while (mac_isgraph(*s) && *s != ':')
 977   {
 978   if (ptr < max-1) name[ptr++] = *s;
 979   s++;
 980   }
 981 if (*s == ':') s++;
 982 name[ptr++] = ':';
 983 name[ptr] = 0;
 984 return s;
 985 }
 986
 987
 988
 989 /*************************************************
 990 *           Pick out a number from a string      *
 991 *************************************************/
 992
 993 /* Arguments:
 994   n     points to an integer into which to put the number
 995   s     points to the first digit of the number
 996
 997 Returns:  a pointer to the character after the last digit
 998 */
 999
1000 static uschar *
1001 read_number(int *n, uschar *s)
1002 {
1003 *n = 0;
1004 while (isdigit(*s)) *n = *n * 10 + (*s++ - '0');
1005 return s;
1006 }
1007
1008
1009
1010 /*************************************************
1011 *        Extract keyed subfield from a string    *
1012 *************************************************/
1013
1014 /* The yield is in dynamic store; NULL means that the key was not found.
1015
1016 Arguments:
1017   key       points to the name of the key
1018   s         points to the string from which to extract the subfield
1019
1020 Returns:    NULL if the subfield was not found, or
1021             a pointer to the subfield's data
1022 */
1023
1024 static uschar *
1025 expand_getkeyed(uschar *key, uschar *s)
1026 {
1027 int length = Ustrlen(key);
1028 while (isspace(*s)) s++;
1029
1030 /* Loop to search for the key */
1031
1032 while (*s != 0)
1033   {
1034   int dkeylength;
1035   uschar *data;
1036   uschar *dkey = s;
1037
1038   while (*s != 0 && *s != '=' && !isspace(*s)) s++;
1039   dkeylength = s - dkey;
1040   while (isspace(*s)) s++;
1041   if (*s == '=') while (isspace((*(++s))));
1042
1043   data = string_dequote(&s);
1044   if (length == dkeylength && strncmpic(key, dkey, length) == 0)
1045     return data;
1046
1047   while (isspace(*s)) s++;
1048   }
1049
1050 return NULL;
1051 }
1052
1053
1054
1055
1056 /*************************************************
1057 *   Extract numbered subfield from string        *
1058 *************************************************/
1059
1060 /* Extracts a numbered field from a string that is divided by tokens - for
1061 example a line from /etc/passwd is divided by colon characters.  First field is
1062 numbered one.  Negative arguments count from the right. Zero returns the whole
1063 string. Returns NULL if there are insufficient tokens in the string
1064
1065 ***WARNING***
1066 Modifies final argument - this is a dynamically generated string, so that's OK.
1067
1068 Arguments:
1069   field       number of field to be extracted,
1070                 first field = 1, whole string = 0, last field = -1
1071   separators  characters that are used to break string into tokens
1072   s           points to the string from which to extract the subfield
1073
1074 Returns:      NULL if the field was not found,
1075               a pointer to the field's data inside s (modified to add 0)
1076 */
1077
1078 static uschar *
1079 expand_gettokened (int field, uschar *separators, uschar *s)
1080 {
1081 int sep = 1;
1082 int count;
1083 uschar *ss = s;
1084 uschar *fieldtext = NULL;
1085
1086 if (field == 0) return s;
1087
1088 /* Break the line up into fields in place; for field > 0 we stop when we have
1089 done the number of fields we want. For field < 0 we continue till the end of
1090 the string, counting the number of fields. */
1091
1092 count = (field > 0)? field : INT_MAX;
1093
1094 while (count-- > 0)
1095   {
1096   size_t len;
1097
1098   /* Previous field was the last one in the string. For a positive field
1099   number, this means there are not enough fields. For a negative field number,
1100   check that there are enough, and scan back to find the one that is wanted. */
1101
1102   if (sep == 0)
1103     {
1104     if (field > 0 || (-field) > (INT_MAX - count - 1)) return NULL;
1105     if ((-field) == (INT_MAX - count - 1)) return s;
1106     while (field++ < 0)
1107       {
1108       ss--;
1109       while (ss[-1] != 0) ss--;
1110       }
1111     fieldtext = ss;
1112     break;
1113     }
1114
1115   /* Previous field was not last in the string; save its start and put a
1116   zero at its end. */
1117
1118   fieldtext = ss;
1119   len = Ustrcspn(ss, separators);
1120   sep = ss[len];
1121   ss[len] = 0;
1122   ss += len + 1;
1123   }
1124
1125 return fieldtext;
1126 }
1127
1128
1129
1130 /*************************************************
1131 *        Extract a substring from a string       *
1132 *************************************************/
1133
1134 /* Perform the ${substr or ${length expansion operations.
1135
1136 Arguments:
1137   subject     the input string
1138   value1      the offset from the start of the input string to the start of
1139                 the output string; if negative, count from the right.
1140   value2      the length of the output string, or negative (-1) for unset
1141                 if value1 is positive, unset means "all after"
1142                 if value1 is negative, unset means "all before"
1143   len         set to the length of the returned string
1144
1145 Returns:      pointer to the output string, or NULL if there is an error
1146 */
1147
1148 static uschar *
1149 extract_substr(uschar *subject, int value1, int value2, int *len)
1150 {
1151 int sublen = Ustrlen(subject);
1152
1153 if (value1 < 0)    /* count from right */
1154   {
1155   value1 += sublen;
1156
1157   /* If the position is before the start, skip to the start, and adjust the
1158   length. If the length ends up negative, the substring is null because nothing
1159   can precede. This falls out naturally when the length is unset, meaning "all
1160   to the left". */
1161
1162   if (value1 < 0)
1163     {
1164     value2 += value1;
1165     if (value2 < 0) value2 = 0;
1166     value1 = 0;
1167     }
1168
1169   /* Otherwise an unset length => characters before value1 */
1170
1171   else if (value2 < 0)
1172     {
1173     value2 = value1;
1174     value1 = 0;
1175     }
1176   }
1177
1178 /* For a non-negative offset, if the starting position is past the end of the
1179 string, the result will be the null string. Otherwise, an unset length means
1180 "rest"; just set it to the maximum - it will be cut down below if necessary. */
1181
1182 else
1183   {
1184   if (value1 > sublen)
1185     {
1186     value1 = sublen;
1187     value2 = 0;
1188     }
1189   else if (value2 < 0) value2 = sublen;
1190   }
1191
1192 /* Cut the length down to the maximum possible for the offset value, and get
1193 the required characters. */
1194
1195 if (value1 + value2 > sublen) value2 = sublen - value1;
1196 *len = value2;
1197 return subject + value1;
1198 }
1199
1200
1201
1202
1203 /*************************************************
1204 *            Old-style hash of a string          *
1205 *************************************************/
1206
1207 /* Perform the ${hash expansion operation.
1208
1209 Arguments:
1210   subject     the input string (an expanded substring)
1211   value1      the length of the output string; if greater or equal to the
1212                 length of the input string, the input string is returned
1213   value2      the number of hash characters to use, or 26 if negative
1214   len         set to the length of the returned string
1215
1216 Returns:      pointer to the output string, or NULL if there is an error
1217 */
1218
1219 static uschar *
1220 compute_hash(uschar *subject, int value1, int value2, int *len)
1221 {
1222 int sublen = Ustrlen(subject);
1223
1224 if (value2 < 0) value2 = 26;
1225 else if (value2 > Ustrlen(hashcodes))
1226   {
1227   expand_string_message =
1228     string_sprintf("hash count \"%d\" too big", value2);
1229   return NULL;
1230   }
1231
1232 /* Calculate the hash text. We know it is shorter than the original string, so
1233 can safely place it in subject[] (we know that subject is always itself an
1234 expanded substring). */
1235
1236 if (value1 < sublen)
1237   {
1238   int c;
1239   int i = 0;
1240   int j = value1;
1241   while ((c = (subject[j])) != 0)
1242     {
1243     int shift = (c + j++) & 7;
1244     subject[i] ^= (c << shift) | (c >> (8-shift));
1245     if (++i >= value1) i = 0;
1246     }
1247   for (i = 0; i < value1; i++)
1248     subject[i] = hashcodes[(subject[i]) % value2];
1249   }
1250 else value1 = sublen;
1251
1252 *len = value1;
1253 return subject;
1254 }
1255
1256
1257
1258
1259 /*************************************************
1260 *             Numeric hash of a string           *
1261 *************************************************/
1262
1263 /* Perform the ${nhash expansion operation. The first characters of the
1264 string are treated as most important, and get the highest prime numbers.
1265
1266 Arguments:
1267   subject     the input string
1268   value1      the maximum value of the first part of the result
1269   value2      the maximum value of the second part of the result,
1270                 or negative to produce only a one-part result
1271   len         set to the length of the returned string
1272
1273 Returns:  pointer to the output string, or NULL if there is an error.
1274 */
1275
1276 static uschar *
1277 compute_nhash (uschar *subject, int value1, int value2, int *len)
1278 {
1279 uschar *s = subject;
1280 int i = 0;
1281 unsigned long int total = 0; /* no overflow */
1282
1283 while (*s != 0)
1284   {
1285   if (i == 0) i = sizeof(prime)/sizeof(int) - 1;
1286   total += prime[i--] * (unsigned int)(*s++);
1287   }
1288
1289 /* If value2 is unset, just compute one number */
1290
1291 if (value2 < 0)
1292   {
1293   s = string_sprintf("%d", total % value1);
1294   }
1295
1296 /* Otherwise do a div/mod hash */
1297
1298 else
1299   {
1300   total = total % (value1 * value2);
1301   s = string_sprintf("%d/%d", total/value2, total % value2);
1302   }
1303
1304 *len = Ustrlen(s);
1305 return s;
1306 }
1307
1308
1309
1310
1311
1312 /*************************************************
1313 *     Find the value of a header or headers      *
1314 *************************************************/
1315
1316 /* Multiple instances of the same header get concatenated, and this function
1317 can also return a concatenation of all the header lines. When concatenating
1318 specific headers that contain lists of addresses, a comma is inserted between
1319 them. Otherwise we use a straight concatenation. Because some messages can have
1320 pathologically large number of lines, there is a limit on the length that is
1321 returned. Also, to avoid massive store use which would result from using
1322 string_cat() as it copies and extends strings, we do a preliminary pass to find
1323 out exactly how much store will be needed. On "normal" messages this will be
1324 pretty trivial.
1325
1326 Arguments:
1327   name          the name of the header, without the leading $header_ or $h_,
1328                 or NULL if a concatenation of all headers is required
1329   exists_only   TRUE if called from a def: test; don't need to build a string;
1330                 just return a string that is not "" and not "0" if the header
1331                 exists
1332   newsize       return the size of memory block that was obtained; may be NULL
1333                 if exists_only is TRUE
1334   want_raw      TRUE if called for $rh_ or $rheader_ variables; no processing,
1335                 other than concatenating, will be done on the header. Also used
1336                 for $message_headers_raw.
1337   charset       name of charset to translate MIME words to; used only if
1338                 want_raw is false; if NULL, no translation is done (this is
1339                 used for $bh_ and $bheader_)
1340
1341 Returns:        NULL if the header does not exist, else a pointer to a new
1342                 store block
1343 */
1344
1345 static uschar *
1346 find_header(uschar *name, BOOL exists_only, int *newsize, BOOL want_raw,
1347   uschar *charset)
1348 {
1349 BOOL found = name == NULL;
1350 int comma = 0;
1351 int len = found? 0 : Ustrlen(name);
1352 int i;
1353 uschar *yield = NULL;
1354 uschar *ptr = NULL;
1355
1356 /* Loop for two passes - saves code repetition */
1357
1358 for (i = 0; i < 2; i++)
1359   {
1360   int size = 0;
1361   header_line *h;
1362
1363   for (h = header_list; size < header_insert_maxlen && h != NULL; h = h->next)
1364     {
1365     if (h->type != htype_old && h->text != NULL)  /* NULL => Received: placeholder */
1366       {
1367       if (name == NULL || (len <= h->slen && strncmpic(name, h->text, len) == 0))
1368         {
1369         int ilen;
1370         uschar *t;
1371
1372         if (exists_only) return US"1";      /* don't need actual string */
1373         found = TRUE;
1374         t = h->text + len;                  /* text to insert */
1375         if (!want_raw)                      /* unless wanted raw, */
1376           while (isspace(*t)) t++;          /* remove leading white space */
1377         ilen = h->slen - (t - h->text);     /* length to insert */
1378
1379         /* Unless wanted raw, remove trailing whitespace, including the
1380         newline. */
1381
1382         if (!want_raw)
1383           while (ilen > 0 && isspace(t[ilen-1])) ilen--;
1384
1385         /* Set comma = 1 if handling a single header and it's one of those
1386         that contains an address list, except when asked for raw headers. Only
1387         need to do this once. */
1388
1389         if (!want_raw && name != NULL && comma == 0 &&
1390             Ustrchr("BCFRST", h->type) != NULL)
1391           comma = 1;
1392
1393         /* First pass - compute total store needed; second pass - compute
1394         total store used, including this header. */
1395
1396         size += ilen + comma + 1;  /* +1 for the newline */
1397
1398         /* Second pass - concatentate the data, up to a maximum. Note that
1399         the loop stops when size hits the limit. */
1400
1401         if (i != 0)
1402           {
1403           if (size > header_insert_maxlen)
1404             {
1405             ilen -= size - header_insert_maxlen - 1;
1406             comma = 0;
1407             }
1408           Ustrncpy(ptr, t, ilen);
1409           ptr += ilen;
1410
1411           /* For a non-raw header, put in the comma if needed, then add
1412           back the newline we removed above, provided there was some text in
1413           the header. */
1414
1415           if (!want_raw && ilen > 0)
1416             {
1417             if (comma != 0) *ptr++ = ',';
1418             *ptr++ = '\n';
1419             }
1420           }
1421         }
1422       }
1423     }
1424
1425   /* At end of first pass, return NULL if no header found. Then truncate size
1426   if necessary, and get the buffer to hold the data, returning the buffer size.
1427   */
1428
1429   if (i == 0)
1430     {
1431     if (!found) return NULL;
1432     if (size > header_insert_maxlen) size = header_insert_maxlen;
1433     *newsize = size + 1;
1434     ptr = yield = store_get(*newsize);
1435     }
1436   }
1437
1438 /* That's all we do for raw header expansion. */
1439
1440 if (want_raw)
1441   {
1442   *ptr = 0;
1443   }
1444
1445 /* Otherwise, remove a final newline and a redundant added comma. Then we do
1446 RFC 2047 decoding, translating the charset if requested. The rfc2047_decode2()
1447 function can return an error with decoded data if the charset translation
1448 fails. If decoding fails, it returns NULL. */
1449
1450 else
1451   {
1452   uschar *decoded, *error;
1453   if (ptr > yield && ptr[-1] == '\n') ptr--;
1454   if (ptr > yield && comma != 0 && ptr[-1] == ',') ptr--;
1455   *ptr = 0;
1456   decoded = rfc2047_decode2(yield, check_rfc2047_length, charset, '?', NULL,
1457     newsize, &error);
1458   if (error != NULL)
1459     {
1460     DEBUG(D_any) debug_printf("*** error in RFC 2047 decoding: %s\n"
1461       "    input was: %s\n", error, yield);
1462     }
1463   if (decoded != NULL) yield = decoded;
1464   }
1465
1466 return yield;
1467 }
1468
1469
1470
1471
1472 /*************************************************
1473 *               Return list of recipients        *
1474 *************************************************/
1475 /* A recipients list is available only during system message filtering,
1476 during ACL processing after DATA, and while expanding pipe commands
1477 generated from a system filter, but not elsewhere. */
1478
1479 static uschar *
1480 fn_recipients(void)
1481 {
1482 if (!enable_dollar_recipients) return NULL; else
1483   {
1484   int size = 128;
1485   int ptr = 0;
1486   int i;
1487   uschar * s = store_get(size);
1488   for (i = 0; i < recipients_count; i++)
1489     {
1490     if (i != 0) s = string_cat(s, &size, &ptr, US", ", 2);
1491     s = string_cat(s, &size, &ptr, recipients_list[i].address,
1492       Ustrlen(recipients_list[i].address));
1493     }
1494   s[ptr] = 0;     /* string_cat() leaves room */
1495   return s;
1496   }
1497 }
1498
1499
1500 /*************************************************
1501 *               Find value of a variable         *
1502 *************************************************/
1503
1504 /* The table of variables is kept in alphabetic order, so we can search it
1505 using a binary chop. The "choplen" variable is nothing to do with the binary
1506 chop.
1507
1508 Arguments:
1509   name          the name of the variable being sought
1510   exists_only   TRUE if this is a def: test; passed on to find_header()
1511   skipping      TRUE => skip any processing evaluation; this is not the same as
1512                   exists_only because def: may test for values that are first
1513                   evaluated here
1514   newsize       pointer to an int which is initially zero; if the answer is in
1515                 a new memory buffer, *newsize is set to its size
1516
1517 Returns:        NULL if the variable does not exist, or
1518                 a pointer to the variable's contents, or
1519                 something non-NULL if exists_only is TRUE
1520 */
1521
1522 static uschar *
1523 find_variable(uschar *name, BOOL exists_only, BOOL skipping, int *newsize)
1524 {
1525 int first = 0;
1526 int last = var_table_size;
1527
1528 /* Handle ACL variables, whose names are of the form acl_cxxx or acl_mxxx.
1529 Originally, xxx had to be a number in the range 0-9 (later 0-19), but from
1530 release 4.64 onwards arbitrary names are permitted, as long as the first 5
1531 characters are acl_c or acl_m and the sixth is either a digit or an underscore
1532 (this gave backwards compatibility at the changeover). There may be built-in
1533 variables whose names start acl_ but they should never start in this way. This
1534 slightly messy specification is a consequence of the history, needless to say.
1535
1536 If an ACL variable does not exist, treat it as empty, unless strict_acl_vars is
1537 set, in which case give an error. */
1538
1539 if ((Ustrncmp(name, "acl_c", 5) == 0 || Ustrncmp(name, "acl_m", 5) == 0) &&
1540      !isalpha(name[5]))
1541   {
1542   tree_node *node =
1543     tree_search((name[4] == 'c')? acl_var_c : acl_var_m, name + 4);
1544   return (node == NULL)? (strict_acl_vars? NULL : US"") : node->data.ptr;
1545   }
1546
1547 /* Handle $auth<n> variables. */
1548
1549 if (Ustrncmp(name, "auth", 4) == 0)
1550   {
1551   uschar *endptr;
1552   int n = Ustrtoul(name + 4, &endptr, 10);
1553   if (*endptr == 0 && n != 0 && n <= AUTH_VARS)
1554     return (auth_vars[n-1] == NULL)? US"" : auth_vars[n-1];
1555   }
1556
1557 /* For all other variables, search the table */
1558
1559 while (last > first)
1560   {
1561   uschar *s, *domain;
1562   uschar **ss;
1563   int middle = (first + last)/2;
1564   int c = Ustrcmp(name, var_table[middle].name);
1565
1566   if (c > 0) { first = middle + 1; continue; }
1567   if (c < 0) { last = middle; continue; }
1568
1569   /* Found an existing variable. If in skipping state, the value isn't needed,
1570   and we want to avoid processing (such as looking up the host name). */
1571
1572   if (skipping) return US"";
1573
1574   switch (var_table[middle].type)
1575     {
1576     case vtype_filter_int:
1577     if (!filter_running) return NULL;
1578     /* Fall through */
1579     /* VVVVVVVVVVVV */
1580     case vtype_int:
1581     sprintf(CS var_buffer, "%d", *(int *)(var_table[middle].value)); /* Integer */
1582     return var_buffer;
1583
1584     case vtype_ino:
1585     sprintf(CS var_buffer, "%ld", (long int)(*(ino_t *)(var_table[middle].value))); /* Inode */
1586     return var_buffer;
1587
1588     case vtype_gid:
1589     sprintf(CS var_buffer, "%ld", (long int)(*(gid_t *)(var_table[middle].value))); /* gid */
1590     return var_buffer;
1591
1592     case vtype_uid:
1593     sprintf(CS var_buffer, "%ld", (long int)(*(uid_t *)(var_table[middle].value))); /* uid */
1594     return var_buffer;
1595
1596     case vtype_bool:
1597     sprintf(CS var_buffer, "%s", *(BOOL *)(var_table[middle].value) ? "yes" : "no"); /* bool */
1598     return var_buffer;
1599
1600     case vtype_stringptr:                      /* Pointer to string */
1601     s = *((uschar **)(var_table[middle].value));
1602     return (s == NULL)? US"" : s;
1603
1604     case vtype_pid:
1605     sprintf(CS var_buffer, "%d", (int)getpid()); /* pid */
1606     return var_buffer;
1607
1608     case vtype_load_avg:
1609     sprintf(CS var_buffer, "%d", OS_GETLOADAVG()); /* load_average */
1610     return var_buffer;
1611
1612     case vtype_host_lookup:                    /* Lookup if not done so */
1613     if (sender_host_name == NULL && sender_host_address != NULL &&
1614         !host_lookup_failed && host_name_lookup() == OK)
1615       host_build_sender_fullhost();
1616     return (sender_host_name == NULL)? US"" : sender_host_name;
1617
1618     case vtype_localpart:                      /* Get local part from address */
1619     s = *((uschar **)(var_table[middle].value));
1620     if (s == NULL) return US"";
1621     domain = Ustrrchr(s, '@');
1622     if (domain == NULL) return s;
1623     if (domain - s > sizeof(var_buffer) - 1)
1624       log_write(0, LOG_MAIN|LOG_PANIC_DIE, "local part longer than " SIZE_T_FMT
1625           " in string expansion", sizeof(var_buffer));
1626     Ustrncpy(var_buffer, s, domain - s);
1627     var_buffer[domain - s] = 0;
1628     return var_buffer;
1629
1630     case vtype_domain:                         /* Get domain from address */
1631     s = *((uschar **)(var_table[middle].value));
1632     if (s == NULL) return US"";
1633     domain = Ustrrchr(s, '@');
1634     return (domain == NULL)? US"" : domain + 1;
1635
1636     case vtype_msgheaders:
1637     return find_header(NULL, exists_only, newsize, FALSE, NULL);
1638
1639     case vtype_msgheaders_raw:
1640     return find_header(NULL, exists_only, newsize, TRUE, NULL);
1641
1642     case vtype_msgbody:                        /* Pointer to msgbody string */
1643     case vtype_msgbody_end:                    /* Ditto, the end of the msg */
1644     ss = (uschar **)(var_table[middle].value);
1645     if (*ss == NULL && deliver_datafile >= 0)  /* Read body when needed */
1646       {
1647       uschar *body;
1648       off_t start_offset = SPOOL_DATA_START_OFFSET;
1649       int len = message_body_visible;
1650       if (len > message_size) len = message_size;
1651       *ss = body = store_malloc(len+1);
1652       body[0] = 0;
1653       if (var_table[middle].type == vtype_msgbody_end)
1654         {
1655         struct stat statbuf;
1656         if (fstat(deliver_datafile, &statbuf) == 0)
1657           {
1658           start_offset = statbuf.st_size - len;
1659           if (start_offset < SPOOL_DATA_START_OFFSET)
1660             start_offset = SPOOL_DATA_START_OFFSET;
1661           }
1662         }
1663       lseek(deliver_datafile, start_offset, SEEK_SET);
1664       len = read(deliver_datafile, body, len);
1665       if (len > 0)
1666         {
1667         body[len] = 0;
1668         if (message_body_newlines)   /* Separate loops for efficiency */
1669           {
1670           while (len > 0)
1671             { if (body[--len] == 0) body[len] = ' '; }
1672           }
1673         else
1674           {
1675           while (len > 0)
1676             { if (body[--len] == '\n' || body[len] == 0) body[len] = ' '; }
1677           }
1678         }
1679       }
1680     return (*ss == NULL)? US"" : *ss;
1681
1682     case vtype_todbsdin:                       /* BSD inbox time of day */
1683     return tod_stamp(tod_bsdin);
1684
1685     case vtype_tode:                           /* Unix epoch time of day */
1686     return tod_stamp(tod_epoch);
1687
1688     case vtype_todel:                          /* Unix epoch/usec time of day */
1689     return tod_stamp(tod_epoch_l);
1690
1691     case vtype_todf:                           /* Full time of day */
1692     return tod_stamp(tod_full);
1693
1694     case vtype_todl:                           /* Log format time of day */
1695     return tod_stamp(tod_log_bare);            /* (without timezone) */
1696
1697     case vtype_todzone:                        /* Time zone offset only */
1698     return tod_stamp(tod_zone);
1699
1700     case vtype_todzulu:                        /* Zulu time */
1701     return tod_stamp(tod_zulu);
1702
1703     case vtype_todlf:                          /* Log file datestamp tod */
1704     return tod_stamp(tod_log_datestamp_daily);
1705
1706     case vtype_reply:                          /* Get reply address */
1707     s = find_header(US"reply-to:", exists_only, newsize, TRUE,
1708       headers_charset);
1709     if (s != NULL) while (isspace(*s)) s++;
1710     if (s == NULL || *s == 0)
1711       {
1712       *newsize = 0;                            /* For the *s==0 case */
1713       s = find_header(US"from:", exists_only, newsize, TRUE, headers_charset);
1714       }
1715     if (s != NULL)
1716       {
1717       uschar *t;
1718       while (isspace(*s)) s++;
1719       for (t = s; *t != 0; t++) if (*t == '\n') *t = ' ';
1720       while (t > s && isspace(t[-1])) t--;
1721       *t = 0;
1722       }
1723     return (s == NULL)? US"" : s;
1724
1725     case vtype_string_func:
1726       {
1727       uschar * (*fn)() = var_table[middle].value;
1728       return fn();
1729       }
1730
1731     case vtype_pspace:
1732       {
1733       int inodes;
1734       sprintf(CS var_buffer, "%d",
1735         receive_statvfs(var_table[middle].value == (void *)TRUE, &inodes));
1736       }
1737     return var_buffer;
1738
1739     case vtype_pinodes:
1740       {
1741       int inodes;
1742       (void) receive_statvfs(var_table[middle].value == (void *)TRUE, &inodes);
1743       sprintf(CS var_buffer, "%d", inodes);
1744       }
1745     return var_buffer;
1746
1747     #ifndef DISABLE_DKIM
1748     case vtype_dkim:
1749     return dkim_exim_expand_query((int)(long)var_table[middle].value);
1750     #endif
1751
1752     }
1753   }
1754
1755 return NULL;          /* Unknown variable name */
1756 }
1757
1758
1759
1760
1761 void
1762 modify_variable(uschar *name, void * value)
1763 {
1764 int first = 0;
1765 int last = var_table_size;
1766
1767 while (last > first)
1768   {
1769   int middle = (first + last)/2;
1770   int c = Ustrcmp(name, var_table[middle].name);
1771
1772   if (c > 0) { first = middle + 1; continue; }
1773   if (c < 0) { last = middle; continue; }
1774
1775   /* Found an existing variable; change the item it refers to */
1776   var_table[middle].value = value;
1777   return;
1778   }
1779 return;          /* Unknown variable name, fail silently */
1780 }
1781
1782
1783
1784
1785
1786 /*************************************************
1787 *           Read and expand substrings           *
1788 *************************************************/
1789
1790 /* This function is called to read and expand argument substrings for various
1791 expansion items. Some have a minimum requirement that is less than the maximum;
1792 in these cases, the first non-present one is set to NULL.
1793
1794 Arguments:
1795   sub        points to vector of pointers to set
1796   n          maximum number of substrings
1797   m          minimum required
1798   sptr       points to current string pointer
1799   skipping   the skipping flag
1800   check_end  if TRUE, check for final '}'
1801   name       name of item, for error message
1802
1803 Returns:     0 OK; string pointer updated
1804              1 curly bracketing error (too few arguments)
1805              2 too many arguments (only if check_end is set); message set
1806              3 other error (expansion failure)
1807 */
1808
1809 static int
1810 read_subs(uschar **sub, int n, int m, uschar **sptr, BOOL skipping,
1811   BOOL check_end, uschar *name)
1812 {
1813 int i;
1814 uschar *s = *sptr;
1815
1816 while (isspace(*s)) s++;
1817 for (i = 0; i < n; i++)
1818   {
1819   if (*s != '{')
1820     {
1821     if (i < m) return 1;
1822     sub[i] = NULL;
1823     break;
1824     }
1825   sub[i] = expand_string_internal(s+1, TRUE, &s, skipping, TRUE);
1826   if (sub[i] == NULL) return 3;
1827   if (*s++ != '}') return 1;
1828   while (isspace(*s)) s++;
1829   }
1830 if (check_end && *s++ != '}')
1831   {
1832   if (s[-1] == '{')
1833     {
1834     expand_string_message = string_sprintf("Too many arguments for \"%s\" "
1835       "(max is %d)", name, n);
1836     return 2;
1837     }
1838   return 1;
1839   }
1840
1841 *sptr = s;
1842 return 0;
1843 }
1844
1845
1846
1847
1848 /*************************************************
1849 *     Elaborate message for bad variable         *
1850 *************************************************/
1851
1852 /* For the "unknown variable" message, take a look at the variable's name, and
1853 give additional information about possible ACL variables. The extra information
1854 is added on to expand_string_message.
1855
1856 Argument:   the name of the variable
1857 Returns:    nothing
1858 */
1859
1860 static void
1861 check_variable_error_message(uschar *name)
1862 {
1863 if (Ustrncmp(name, "acl_", 4) == 0)
1864   expand_string_message = string_sprintf("%s (%s)", expand_string_message,
1865     (name[4] == 'c' || name[4] == 'm')?
1866       (isalpha(name[5])?
1867         US"6th character of a user-defined ACL variable must be a digit or underscore" :
1868         US"strict_acl_vars is set"    /* Syntax is OK, it has to be this */
1869       ) :
1870       US"user-defined ACL variables must start acl_c or acl_m");
1871 }
1872
1873
1874
1875 /*
1876 Load args from sub array to globals, and call acl_check().
1877 Sub array will be corrupted on return.
1878
1879 Returns:       OK         access is granted by an ACCEPT verb
1880                DISCARD    access is granted by a DISCARD verb
1881                FAIL       access is denied
1882                FAIL_DROP  access is denied; drop the connection
1883                DEFER      can't tell at the moment
1884                ERROR      disaster
1885 */
1886 static int
1887 eval_acl(uschar ** sub, int nsub, uschar ** user_msgp)
1888 {
1889 int i;
1890 uschar *tmp;
1891 int sav_narg = acl_narg;
1892 int ret;
1893 extern int acl_where;
1894
1895 if(--nsub > sizeof(acl_arg)/sizeof(*acl_arg)) nsub = sizeof(acl_arg)/sizeof(*acl_arg);
1896 for (i = 0; i < nsub && sub[i+1]; i++)
1897   {
1898   tmp = acl_arg[i];
1899   acl_arg[i] = sub[i+1];        /* place callers args in the globals */
1900   sub[i+1] = tmp;               /* stash the old args using our caller's storage */
1901   }
1902 acl_narg = i;
1903 while (i < nsub)
1904   {
1905   sub[i+1] = acl_arg[i];
1906   acl_arg[i++] = NULL;
1907   }
1908
1909 DEBUG(D_expand)
1910   debug_printf("expanding: acl: %s  arg: %s%s\n",
1911     sub[0],
1912     acl_narg>0 ? acl_arg[0] : US"<none>",
1913     acl_narg>1 ? " +more"   : "");
1914
1915 ret = acl_eval(acl_where, sub[0], user_msgp, &tmp);
1916
1917 for (i = 0; i < nsub; i++)
1918   acl_arg[i] = sub[i+1];        /* restore old args */
1919 acl_narg = sav_narg;
1920
1921 return ret;
1922 }
1923
1924
1925
1926
1927 /*************************************************
1928 *        Read and evaluate a condition           *
1929 *************************************************/
1930
1931 /*
1932 Arguments:
1933   s        points to the start of the condition text
1934   yield    points to a BOOL to hold the result of the condition test;
1935            if NULL, we are just reading through a condition that is
1936            part of an "or" combination to check syntax, or in a state
1937            where the answer isn't required
1938
1939 Returns:   a pointer to the first character after the condition, or
1940            NULL after an error
1941 */
1942
1943 static uschar *
1944 eval_condition(uschar *s, BOOL *yield)
1945 {
1946 BOOL testfor = TRUE;
1947 BOOL tempcond, combined_cond;
1948 BOOL *subcondptr;
1949 BOOL sub2_honour_dollar = TRUE;
1950 int i, rc, cond_type, roffset;
1951 int_eximarith_t num[2];
1952 struct stat statbuf;
1953 uschar name[256];
1954 uschar *sub[10];
1955
1956 const pcre *re;
1957 const uschar *rerror;
1958
1959 for (;;)
1960   {
1961   while (isspace(*s)) s++;
1962   if (*s == '!') { testfor = !testfor; s++; } else break;
1963   }
1964
1965 /* Numeric comparisons are symbolic */
1966
1967 if (*s == '=' || *s == '>' || *s == '<')
1968   {
1969   int p = 0;
1970   name[p++] = *s++;
1971   if (*s == '=')
1972     {
1973     name[p++] = '=';
1974     s++;
1975     }
1976   name[p] = 0;
1977   }
1978
1979 /* All other conditions are named */
1980
1981 else s = read_name(name, 256, s, US"_");
1982
1983 /* If we haven't read a name, it means some non-alpha character is first. */
1984
1985 if (name[0] == 0)
1986   {
1987   expand_string_message = string_sprintf("condition name expected, "
1988     "but found \"%.16s\"", s);
1989   return NULL;
1990   }
1991
1992 /* Find which condition we are dealing with, and switch on it */
1993
1994 cond_type = chop_match(name, cond_table, sizeof(cond_table)/sizeof(uschar *));
1995 switch(cond_type)
1996   {
1997   /* def: tests for a non-empty variable, or for the existence of a header. If
1998   yield == NULL we are in a skipping state, and don't care about the answer. */
1999
2000   case ECOND_DEF:
2001   if (*s != ':')
2002     {
2003     expand_string_message = US"\":\" expected after \"def\"";
2004     return NULL;
2005     }
2006
2007   s = read_name(name, 256, s+1, US"_");
2008
2009   /* Test for a header's existence. If the name contains a closing brace
2010   character, this may be a user error where the terminating colon has been
2011   omitted. Set a flag to adjust a subsequent error message in this case. */
2012
2013   if (Ustrncmp(name, "h_", 2) == 0 ||
2014       Ustrncmp(name, "rh_", 3) == 0 ||
2015       Ustrncmp(name, "bh_", 3) == 0 ||
2016       Ustrncmp(name, "header_", 7) == 0 ||
2017       Ustrncmp(name, "rheader_", 8) == 0 ||
2018       Ustrncmp(name, "bheader_", 8) == 0)
2019     {
2020     s = read_header_name(name, 256, s);
2021     /* {-for-text-editors */
2022     if (Ustrchr(name, '}') != NULL) malformed_header = TRUE;
2023     if (yield != NULL) *yield =
2024       (find_header(name, TRUE, NULL, FALSE, NULL) != NULL) == testfor;
2025     }
2026
2027   /* Test for a variable's having a non-empty value. A non-existent variable
2028   causes an expansion failure. */
2029
2030   else
2031     {
2032     uschar *value = find_variable(name, TRUE, yield == NULL, NULL);
2033     if (value == NULL)
2034       {
2035       expand_string_message = (name[0] == 0)?
2036         string_sprintf("variable name omitted after \"def:\"") :
2037         string_sprintf("unknown variable \"%s\" after \"def:\"", name);
2038       check_variable_error_message(name);
2039       return NULL;
2040       }
2041     if (yield != NULL) *yield = (value[0] != 0) == testfor;
2042     }
2043
2044   return s;
2045
2046
2047   /* first_delivery tests for first delivery attempt */
2048
2049   case ECOND_FIRST_DELIVERY:
2050   if (yield != NULL) *yield = deliver_firsttime == testfor;
2051   return s;
2052
2053
2054   /* queue_running tests for any process started by a queue runner */
2055
2056   case ECOND_QUEUE_RUNNING:
2057   if (yield != NULL) *yield = (queue_run_pid != (pid_t)0) == testfor;
2058   return s;
2059
2060
2061   /* exists:  tests for file existence
2062        isip:  tests for any IP address
2063       isip4:  tests for an IPv4 address
2064       isip6:  tests for an IPv6 address
2065         pam:  does PAM authentication
2066      radius:  does RADIUS authentication
2067    ldapauth:  does LDAP authentication
2068     pwcheck:  does Cyrus SASL pwcheck authentication
2069   */
2070
2071   case ECOND_EXISTS:
2072   case ECOND_ISIP:
2073   case ECOND_ISIP4:
2074   case ECOND_ISIP6:
2075   case ECOND_PAM:
2076   case ECOND_RADIUS:
2077   case ECOND_LDAPAUTH:
2078   case ECOND_PWCHECK:
2079
2080   while (isspace(*s)) s++;
2081   if (*s != '{') goto COND_FAILED_CURLY_START;          /* }-for-text-editors */
2082
2083   sub[0] = expand_string_internal(s+1, TRUE, &s, yield == NULL, TRUE);
2084   if (sub[0] == NULL) return NULL;
2085   /* {-for-text-editors */
2086   if (*s++ != '}') goto COND_FAILED_CURLY_END;
2087
2088   if (yield == NULL) return s;   /* No need to run the test if skipping */
2089
2090   switch(cond_type)
2091     {
2092     case ECOND_EXISTS:
2093     if ((expand_forbid & RDO_EXISTS) != 0)
2094       {
2095       expand_string_message = US"File existence tests are not permitted";
2096       return NULL;
2097       }
2098     *yield = (Ustat(sub[0], &statbuf) == 0) == testfor;
2099     break;
2100
2101     case ECOND_ISIP:
2102     case ECOND_ISIP4:
2103     case ECOND_ISIP6:
2104     rc = string_is_ip_address(sub[0], NULL);
2105     *yield = ((cond_type == ECOND_ISIP)? (rc != 0) :
2106              (cond_type == ECOND_ISIP4)? (rc == 4) : (rc == 6)) == testfor;
2107     break;
2108
2109     /* Various authentication tests - all optionally compiled */
2110
2111     case ECOND_PAM:
2112     #ifdef SUPPORT_PAM
2113     rc = auth_call_pam(sub[0], &expand_string_message);
2114     goto END_AUTH;
2115     #else
2116     goto COND_FAILED_NOT_COMPILED;
2117     #endif  /* SUPPORT_PAM */
2118
2119     case ECOND_RADIUS:
2120     #ifdef RADIUS_CONFIG_FILE
2121     rc = auth_call_radius(sub[0], &expand_string_message);
2122     goto END_AUTH;
2123     #else
2124     goto COND_FAILED_NOT_COMPILED;
2125     #endif  /* RADIUS_CONFIG_FILE */
2126
2127     case ECOND_LDAPAUTH:
2128     #ifdef LOOKUP_LDAP
2129       {
2130       /* Just to keep the interface the same */
2131       BOOL do_cache;
2132       int old_pool = store_pool;
2133       store_pool = POOL_SEARCH;
2134       rc = eldapauth_find((void *)(-1), NULL, sub[0], Ustrlen(sub[0]), NULL,
2135         &expand_string_message, &do_cache);
2136       store_pool = old_pool;
2137       }
2138     goto END_AUTH;
2139     #else
2140     goto COND_FAILED_NOT_COMPILED;
2141     #endif  /* LOOKUP_LDAP */
2142
2143     case ECOND_PWCHECK:
2144     #ifdef CYRUS_PWCHECK_SOCKET
2145     rc = auth_call_pwcheck(sub[0], &expand_string_message);
2146     goto END_AUTH;
2147     #else
2148     goto COND_FAILED_NOT_COMPILED;
2149     #endif  /* CYRUS_PWCHECK_SOCKET */
2150
2151     #if defined(SUPPORT_PAM) || defined(RADIUS_CONFIG_FILE) || \
2152         defined(LOOKUP_LDAP) || defined(CYRUS_PWCHECK_SOCKET)
2153     END_AUTH:
2154     if (rc == ERROR || rc == DEFER) return NULL;
2155     *yield = (rc == OK) == testfor;
2156     #endif
2157     }
2158   return s;
2159
2160
2161   /* call ACL (in a conditional context).  Accept true, deny false.
2162   Defer is a forced-fail.  Anything set by message= goes to $value.
2163   Up to ten parameters are used; we use the braces round the name+args
2164   like the saslauthd condition does, to permit a variable number of args.
2165   See also the expansion-item version EITEM_ACL and the traditional
2166   acl modifier ACLC_ACL.
2167   */
2168
2169   case ECOND_ACL:
2170     /* ${if acl {{name}{arg1}{arg2}...}  {yes}{no}} */
2171     {
2172     uschar *user_msg;
2173     BOOL cond = FALSE;
2174     int size = 0;
2175     int ptr = 0;
2176
2177     while (isspace(*s)) s++;
2178     if (*s++ != '{') goto COND_FAILED_CURLY_START;      /*}*/
2179
2180     switch(read_subs(sub, sizeof(sub)/sizeof(*sub), 1,
2181       &s, yield == NULL, TRUE, US"acl"))
2182       {
2183       case 1: expand_string_message = US"too few arguments or bracketing "
2184         "error for acl";
2185       case 2:
2186       case 3: return NULL;
2187       }
2188
2189     if (yield != NULL) switch(eval_acl(sub, sizeof(sub)/sizeof(*sub), &user_msg))
2190         {
2191         case OK:
2192           cond = TRUE;
2193         case FAIL:
2194           lookup_value = NULL;
2195           if (user_msg)
2196             {
2197             lookup_value = string_cat(NULL, &size, &ptr, user_msg, Ustrlen(user_msg));
2198             lookup_value[ptr] = '\0';
2199             }
2200           *yield = cond == testfor;
2201           break;
2202
2203         case DEFER:
2204           expand_string_forcedfail = TRUE;
2205         default:
2206           expand_string_message = string_sprintf("error from acl \"%s\"", sub[0]);
2207           return NULL;
2208         }
2209     return s;
2210     }
2211
2212
2213   /* saslauthd: does Cyrus saslauthd authentication. Four parameters are used:
2214
2215      ${if saslauthd {{username}{password}{service}{realm}}  {yes}[no}}
2216
2217   However, the last two are optional. That is why the whole set is enclosed
2218   in their own set of braces. */
2219
2220   case ECOND_SASLAUTHD:
2221   #ifndef CYRUS_SASLAUTHD_SOCKET
2222   goto COND_FAILED_NOT_COMPILED;
2223   #else
2224   while (isspace(*s)) s++;
2225   if (*s++ != '{') goto COND_FAILED_CURLY_START;        /* }-for-text-editors */
2226   switch(read_subs(sub, 4, 2, &s, yield == NULL, TRUE, US"saslauthd"))
2227     {
2228     case 1: expand_string_message = US"too few arguments or bracketing "
2229       "error for saslauthd";
2230     case 2:
2231     case 3: return NULL;
2232     }
2233   if (sub[2] == NULL) sub[3] = NULL;  /* realm if no service */
2234   if (yield != NULL)
2235     {
2236     int rc;
2237     rc = auth_call_saslauthd(sub[0], sub[1], sub[2], sub[3],
2238       &expand_string_message);
2239     if (rc == ERROR || rc == DEFER) return NULL;
2240     *yield = (rc == OK) == testfor;
2241     }
2242   return s;
2243   #endif /* CYRUS_SASLAUTHD_SOCKET */
2244
2245
2246   /* symbolic operators for numeric and string comparison, and a number of
2247   other operators, all requiring two arguments.
2248
2249   crypteq:           encrypts plaintext and compares against an encrypted text,
2250                        using crypt(), crypt16(), MD5 or SHA-1
2251   inlist/inlisti:    checks if first argument is in the list of the second
2252   match:             does a regular expression match and sets up the numerical
2253                        variables if it succeeds
2254   match_address:     matches in an address list
2255   match_domain:      matches in a domain list
2256   match_ip:          matches a host list that is restricted to IP addresses
2257   match_local_part:  matches in a local part list
2258   */
2259
2260   case ECOND_MATCH_ADDRESS:
2261   case ECOND_MATCH_DOMAIN:
2262   case ECOND_MATCH_IP:
2263   case ECOND_MATCH_LOCAL_PART:
2264 #ifndef EXPAND_LISTMATCH_RHS
2265     sub2_honour_dollar = FALSE;
2266 #endif
2267     /* FALLTHROUGH */
2268
2269   case ECOND_CRYPTEQ:
2270   case ECOND_INLIST:
2271   case ECOND_INLISTI:
2272   case ECOND_MATCH:
2273
2274   case ECOND_NUM_L:     /* Numerical comparisons */
2275   case ECOND_NUM_LE:
2276   case ECOND_NUM_E:
2277   case ECOND_NUM_EE:
2278   case ECOND_NUM_G:
2279   case ECOND_NUM_GE:
2280
2281   case ECOND_STR_LT:    /* String comparisons */
2282   case ECOND_STR_LTI:
2283   case ECOND_STR_LE:
2284   case ECOND_STR_LEI:
2285   case ECOND_STR_EQ:
2286   case ECOND_STR_EQI:
2287   case ECOND_STR_GT:
2288   case ECOND_STR_GTI:
2289   case ECOND_STR_GE:
2290   case ECOND_STR_GEI:
2291
2292   for (i = 0; i < 2; i++)
2293     {
2294     /* Sometimes, we don't expand substrings; too many insecure configurations
2295     created using match_address{}{} and friends, where the second param
2296     includes information from untrustworthy sources. */
2297     BOOL honour_dollar = TRUE;
2298     if ((i > 0) && !sub2_honour_dollar)
2299       honour_dollar = FALSE;
2300
2301     while (isspace(*s)) s++;
2302     if (*s != '{')
2303       {
2304       if (i == 0) goto COND_FAILED_CURLY_START;
2305       expand_string_message = string_sprintf("missing 2nd string in {} "
2306         "after \"%s\"", name);
2307       return NULL;
2308       }
2309     sub[i] = expand_string_internal(s+1, TRUE, &s, yield == NULL,
2310         honour_dollar);
2311     if (sub[i] == NULL) return NULL;
2312     if (*s++ != '}') goto COND_FAILED_CURLY_END;
2313
2314     /* Convert to numerical if required; we know that the names of all the
2315     conditions that compare numbers do not start with a letter. This just saves
2316     checking for them individually. */
2317
2318     if (!isalpha(name[0]) && yield != NULL)
2319       {
2320       if (sub[i][0] == 0)
2321         {
2322         num[i] = 0;
2323         DEBUG(D_expand)
2324           debug_printf("empty string cast to zero for numerical comparison\n");
2325         }
2326       else
2327         {
2328         num[i] = expand_string_integer(sub[i], FALSE);
2329         if (expand_string_message != NULL) return NULL;
2330         }
2331       }
2332     }
2333
2334   /* Result not required */
2335
2336   if (yield == NULL) return s;
2337
2338   /* Do an appropriate comparison */
2339
2340   switch(cond_type)
2341     {
2342     case ECOND_NUM_E:
2343     case ECOND_NUM_EE:
2344     tempcond = (num[0] == num[1]);
2345     break;
2346
2347     case ECOND_NUM_G:
2348     tempcond = (num[0] > num[1]);
2349     break;
2350
2351     case ECOND_NUM_GE:
2352     tempcond = (num[0] >= num[1]);
2353     break;
2354
2355     case ECOND_NUM_L:
2356     tempcond = (num[0] < num[1]);
2357     break;
2358
2359     case ECOND_NUM_LE:
2360     tempcond = (num[0] <= num[1]);
2361     break;
2362
2363     case ECOND_STR_LT:
2364     tempcond = (Ustrcmp(sub[0], sub[1]) < 0);
2365     break;
2366
2367     case ECOND_STR_LTI:
2368     tempcond = (strcmpic(sub[0], sub[1]) < 0);
2369     break;
2370
2371     case ECOND_STR_LE:
2372     tempcond = (Ustrcmp(sub[0], sub[1]) <= 0);
2373     break;
2374
2375     case ECOND_STR_LEI:
2376     tempcond = (strcmpic(sub[0], sub[1]) <= 0);
2377     break;
2378
2379     case ECOND_STR_EQ:
2380     tempcond = (Ustrcmp(sub[0], sub[1]) == 0);
2381     break;
2382
2383     case ECOND_STR_EQI:
2384     tempcond = (strcmpic(sub[0], sub[1]) == 0);
2385     break;
2386
2387     case ECOND_STR_GT:
2388     tempcond = (Ustrcmp(sub[0], sub[1]) > 0);
2389     break;
2390
2391     case ECOND_STR_GTI:
2392     tempcond = (strcmpic(sub[0], sub[1]) > 0);
2393     break;
2394
2395     case ECOND_STR_GE:
2396     tempcond = (Ustrcmp(sub[0], sub[1]) >= 0);
2397     break;
2398
2399     case ECOND_STR_GEI:
2400     tempcond = (strcmpic(sub[0], sub[1]) >= 0);
2401     break;
2402
2403     case ECOND_MATCH:   /* Regular expression match */
2404     re = pcre_compile(CS sub[1], PCRE_COPT, (const char **)&rerror, &roffset,
2405       NULL);
2406     if (re == NULL)
2407       {
2408       expand_string_message = string_sprintf("regular expression error in "
2409         "\"%s\": %s at offset %d", sub[1], rerror, roffset);
2410       return NULL;
2411       }
2412     tempcond = regex_match_and_setup(re, sub[0], 0, -1);
2413     break;
2414
2415     case ECOND_MATCH_ADDRESS:  /* Match in an address list */
2416     rc = match_address_list(sub[0], TRUE, FALSE, &(sub[1]), NULL, -1, 0, NULL);
2417     goto MATCHED_SOMETHING;
2418
2419     case ECOND_MATCH_DOMAIN:   /* Match in a domain list */
2420     rc = match_isinlist(sub[0], &(sub[1]), 0, &domainlist_anchor, NULL,
2421       MCL_DOMAIN + MCL_NOEXPAND, TRUE, NULL);
2422     goto MATCHED_SOMETHING;
2423
2424     case ECOND_MATCH_IP:       /* Match IP address in a host list */
2425     if (sub[0][0] != 0 && string_is_ip_address(sub[0], NULL) == 0)
2426       {
2427       expand_string_message = string_sprintf("\"%s\" is not an IP address",
2428         sub[0]);
2429       return NULL;
2430       }
2431     else
2432       {
2433       unsigned int *nullcache = NULL;
2434       check_host_block cb;
2435
2436       cb.host_name = US"";
2437       cb.host_address = sub[0];
2438
2439       /* If the host address starts off ::ffff: it is an IPv6 address in
2440       IPv4-compatible mode. Find the IPv4 part for checking against IPv4
2441       addresses. */
2442
2443       cb.host_ipv4 = (Ustrncmp(cb.host_address, "::ffff:", 7) == 0)?
2444         cb.host_address + 7 : cb.host_address;
2445
2446       rc = match_check_list(
2447              &sub[1],                   /* the list */
2448              0,                         /* separator character */
2449              &hostlist_anchor,          /* anchor pointer */
2450              &nullcache,                /* cache pointer */
2451              check_host,                /* function for testing */
2452              &cb,                       /* argument for function */
2453              MCL_HOST,                  /* type of check */
2454              sub[0],                    /* text for debugging */
2455              NULL);                     /* where to pass back data */
2456       }
2457     goto MATCHED_SOMETHING;
2458
2459     case ECOND_MATCH_LOCAL_PART:
2460     rc = match_isinlist(sub[0], &(sub[1]), 0, &localpartlist_anchor, NULL,
2461       MCL_LOCALPART + MCL_NOEXPAND, TRUE, NULL);
2462     /* Fall through */
2463     /* VVVVVVVVVVVV */
2464     MATCHED_SOMETHING:
2465     switch(rc)
2466       {
2467       case OK:
2468       tempcond = TRUE;
2469       break;
2470
2471       case FAIL:
2472       tempcond = FALSE;
2473       break;
2474
2475       case DEFER:
2476       expand_string_message = string_sprintf("unable to complete match "
2477         "against \"%s\": %s", sub[1], search_error_message);
2478       return NULL;
2479       }
2480
2481     break;
2482
2483     /* Various "encrypted" comparisons. If the second string starts with
2484     "{" then an encryption type is given. Default to crypt() or crypt16()
2485     (build-time choice). */
2486     /* }-for-text-editors */
2487
2488     case ECOND_CRYPTEQ:
2489     #ifndef SUPPORT_CRYPTEQ
2490     goto COND_FAILED_NOT_COMPILED;
2491     #else
2492     if (strncmpic(sub[1], US"{md5}", 5) == 0)
2493       {
2494       int sublen = Ustrlen(sub[1]+5);
2495       md5 base;
2496       uschar digest[16];
2497
2498       md5_start(&base);
2499       md5_end(&base, (uschar *)sub[0], Ustrlen(sub[0]), digest);
2500
2501       /* If the length that we are comparing against is 24, the MD5 digest
2502       is expressed as a base64 string. This is the way LDAP does it. However,
2503       some other software uses a straightforward hex representation. We assume
2504       this if the length is 32. Other lengths fail. */
2505
2506       if (sublen == 24)
2507         {
2508         uschar *coded = auth_b64encode((uschar *)digest, 16);
2509         DEBUG(D_auth) debug_printf("crypteq: using MD5+B64 hashing\n"
2510           "  subject=%s\n  crypted=%s\n", coded, sub[1]+5);
2511         tempcond = (Ustrcmp(coded, sub[1]+5) == 0);
2512         }
2513       else if (sublen == 32)
2514         {
2515         int i;
2516         uschar coded[36];
2517         for (i = 0; i < 16; i++) sprintf(CS (coded+2*i), "%02X", digest[i]);
2518         coded[32] = 0;
2519         DEBUG(D_auth) debug_printf("crypteq: using MD5+hex hashing\n"
2520           "  subject=%s\n  crypted=%s\n", coded, sub[1]+5);
2521         tempcond = (strcmpic(coded, sub[1]+5) == 0);
2522         }
2523       else
2524         {
2525         DEBUG(D_auth) debug_printf("crypteq: length for MD5 not 24 or 32: "
2526           "fail\n  crypted=%s\n", sub[1]+5);
2527         tempcond = FALSE;
2528         }
2529       }
2530
2531     else if (strncmpic(sub[1], US"{sha1}", 6) == 0)
2532       {
2533       int sublen = Ustrlen(sub[1]+6);
2534       sha1 base;
2535       uschar digest[20];
2536
2537       sha1_start(&base);
2538       sha1_end(&base, (uschar *)sub[0], Ustrlen(sub[0]), digest);
2539
2540       /* If the length that we are comparing against is 28, assume the SHA1
2541       digest is expressed as a base64 string. If the length is 40, assume a
2542       straightforward hex representation. Other lengths fail. */
2543
2544       if (sublen == 28)
2545         {
2546         uschar *coded = auth_b64encode((uschar *)digest, 20);
2547         DEBUG(D_auth) debug_printf("crypteq: using SHA1+B64 hashing\n"
2548           "  subject=%s\n  crypted=%s\n", coded, sub[1]+6);
2549         tempcond = (Ustrcmp(coded, sub[1]+6) == 0);
2550         }
2551       else if (sublen == 40)
2552         {
2553         int i;
2554         uschar coded[44];
2555         for (i = 0; i < 20; i++) sprintf(CS (coded+2*i), "%02X", digest[i]);
2556         coded[40] = 0;
2557         DEBUG(D_auth) debug_printf("crypteq: using SHA1+hex hashing\n"
2558           "  subject=%s\n  crypted=%s\n", coded, sub[1]+6);
2559         tempcond = (strcmpic(coded, sub[1]+6) == 0);
2560         }
2561       else
2562         {
2563         DEBUG(D_auth) debug_printf("crypteq: length for SHA-1 not 28 or 40: "
2564           "fail\n  crypted=%s\n", sub[1]+6);
2565         tempcond = FALSE;
2566         }
2567       }
2568
2569     else   /* {crypt} or {crypt16} and non-{ at start */
2570            /* }-for-text-editors */
2571       {
2572       int which = 0;
2573       uschar *coded;
2574
2575       if (strncmpic(sub[1], US"{crypt}", 7) == 0)
2576         {
2577         sub[1] += 7;
2578         which = 1;
2579         }
2580       else if (strncmpic(sub[1], US"{crypt16}", 9) == 0)
2581         {
2582         sub[1] += 9;
2583         which = 2;
2584         }
2585       else if (sub[1][0] == '{')                /* }-for-text-editors */
2586         {
2587         expand_string_message = string_sprintf("unknown encryption mechanism "
2588           "in \"%s\"", sub[1]);
2589         return NULL;
2590         }
2591
2592       switch(which)
2593         {
2594         case 0:  coded = US DEFAULT_CRYPT(CS sub[0], CS sub[1]); break;
2595         case 1:  coded = US crypt(CS sub[0], CS sub[1]); break;
2596         default: coded = US crypt16(CS sub[0], CS sub[1]); break;
2597         }
2598
2599       #define STR(s) # s
2600       #define XSTR(s) STR(s)
2601       DEBUG(D_auth) debug_printf("crypteq: using %s()\n"
2602         "  subject=%s\n  crypted=%s\n",
2603         (which == 0)? XSTR(DEFAULT_CRYPT) : (which == 1)? "crypt" : "crypt16",
2604         coded, sub[1]);
2605       #undef STR
2606       #undef XSTR
2607
2608       /* If the encrypted string contains fewer than two characters (for the
2609       salt), force failure. Otherwise we get false positives: with an empty
2610       string the yield of crypt() is an empty string! */
2611
2612       tempcond = (Ustrlen(sub[1]) < 2)? FALSE :
2613         (Ustrcmp(coded, sub[1]) == 0);
2614       }
2615     break;
2616     #endif  /* SUPPORT_CRYPTEQ */
2617
2618     case ECOND_INLIST:
2619     case ECOND_INLISTI:
2620       {
2621       int sep = 0;
2622       uschar *save_iterate_item = iterate_item;
2623       int (*compare)(const uschar *, const uschar *);
2624
2625       tempcond = FALSE;
2626       if (cond_type == ECOND_INLISTI)
2627         compare = strcmpic;
2628       else
2629         compare = (int (*)(const uschar *, const uschar *)) strcmp;
2630
2631       while ((iterate_item = string_nextinlist(&sub[1], &sep, NULL, 0)) != NULL)
2632         if (compare(sub[0], iterate_item) == 0)
2633           {
2634           tempcond = TRUE;
2635           break;
2636           }
2637       iterate_item = save_iterate_item;
2638       }
2639
2640     }   /* Switch for comparison conditions */
2641
2642   *yield = tempcond == testfor;
2643   return s;    /* End of comparison conditions */
2644
2645
2646   /* and/or: computes logical and/or of several conditions */
2647
2648   case ECOND_AND:
2649   case ECOND_OR:
2650   subcondptr = (yield == NULL)? NULL : &tempcond;
2651   combined_cond = (cond_type == ECOND_AND);
2652
2653   while (isspace(*s)) s++;
2654   if (*s++ != '{') goto COND_FAILED_CURLY_START;        /* }-for-text-editors */
2655
2656   for (;;)
2657     {
2658     while (isspace(*s)) s++;
2659     /* {-for-text-editors */
2660     if (*s == '}') break;
2661     if (*s != '{')                                      /* }-for-text-editors */
2662       {
2663       expand_string_message = string_sprintf("each subcondition "
2664         "inside an \"%s{...}\" condition must be in its own {}", name);
2665       return NULL;
2666       }
2667
2668     s = eval_condition(s+1, subcondptr);
2669     if (s == NULL)
2670       {
2671       expand_string_message = string_sprintf("%s inside \"%s{...}\" condition",
2672         expand_string_message, name);
2673       return NULL;
2674       }
2675     while (isspace(*s)) s++;
2676
2677     /* {-for-text-editors */
2678     if (*s++ != '}')
2679       {
2680       /* {-for-text-editors */
2681       expand_string_message = string_sprintf("missing } at end of condition "
2682         "inside \"%s\" group", name);
2683       return NULL;
2684       }
2685
2686     if (yield != NULL)
2687       {
2688       if (cond_type == ECOND_AND)
2689         {
2690         combined_cond &= tempcond;
2691         if (!combined_cond) subcondptr = NULL;  /* once false, don't */
2692         }                                       /* evaluate any more */
2693       else
2694         {
2695         combined_cond |= tempcond;
2696         if (combined_cond) subcondptr = NULL;   /* once true, don't */
2697         }                                       /* evaluate any more */
2698       }
2699     }
2700
2701   if (yield != NULL) *yield = (combined_cond == testfor);
2702   return ++s;
2703
2704
2705   /* forall/forany: iterates a condition with different values */
2706
2707   case ECOND_FORALL:
2708   case ECOND_FORANY:
2709     {
2710     int sep = 0;
2711     uschar *save_iterate_item = iterate_item;
2712
2713     while (isspace(*s)) s++;
2714     if (*s++ != '{') goto COND_FAILED_CURLY_START;      /* }-for-text-editors */
2715     sub[0] = expand_string_internal(s, TRUE, &s, (yield == NULL), TRUE);
2716     if (sub[0] == NULL) return NULL;
2717     /* {-for-text-editors */
2718     if (*s++ != '}') goto COND_FAILED_CURLY_END;
2719
2720     while (isspace(*s)) s++;
2721     if (*s++ != '{') goto COND_FAILED_CURLY_START;      /* }-for-text-editors */
2722
2723     sub[1] = s;
2724
2725     /* Call eval_condition once, with result discarded (as if scanning a
2726     "false" part). This allows us to find the end of the condition, because if
2727     the list it empty, we won't actually evaluate the condition for real. */
2728
2729     s = eval_condition(sub[1], NULL);
2730     if (s == NULL)
2731       {
2732       expand_string_message = string_sprintf("%s inside \"%s\" condition",
2733         expand_string_message, name);
2734       return NULL;
2735       }
2736     while (isspace(*s)) s++;
2737
2738     /* {-for-text-editors */
2739     if (*s++ != '}')
2740       {
2741       /* {-for-text-editors */
2742       expand_string_message = string_sprintf("missing } at end of condition "
2743         "inside \"%s\"", name);
2744       return NULL;
2745       }
2746
2747     if (yield != NULL) *yield = !testfor;
2748     while ((iterate_item = string_nextinlist(&sub[0], &sep, NULL, 0)) != NULL)
2749       {
2750       DEBUG(D_expand) debug_printf("%s: $item = \"%s\"\n", name, iterate_item);
2751       if (eval_condition(sub[1], &tempcond) == NULL)
2752         {
2753         expand_string_message = string_sprintf("%s inside \"%s\" condition",
2754           expand_string_message, name);
2755         iterate_item = save_iterate_item;
2756         return NULL;
2757         }
2758       DEBUG(D_expand) debug_printf("%s: condition evaluated to %s\n", name,
2759         tempcond? "true":"false");
2760
2761       if (yield != NULL) *yield = (tempcond == testfor);
2762       if (tempcond == (cond_type == ECOND_FORANY)) break;
2763       }
2764
2765     iterate_item = save_iterate_item;
2766     return s;
2767     }
2768
2769
2770   /* The bool{} expansion condition maps a string to boolean.
2771   The values supported should match those supported by the ACL condition
2772   (acl.c, ACLC_CONDITION) so that we keep to a minimum the different ideas
2773   of true/false.  Note that Router "condition" rules have a different
2774   interpretation, where general data can be used and only a few values
2775   map to FALSE.
2776   Note that readconf.c boolean matching, for boolean configuration options,
2777   only matches true/yes/false/no.
2778   The bool_lax{} condition matches the Router logic, which is much more
2779   liberal. */
2780   case ECOND_BOOL:
2781   case ECOND_BOOL_LAX:
2782     {
2783     uschar *sub_arg[1];
2784     uschar *t, *t2;
2785     uschar *ourname;
2786     size_t len;
2787     BOOL boolvalue = FALSE;
2788     while (isspace(*s)) s++;
2789     if (*s != '{') goto COND_FAILED_CURLY_START;        /* }-for-text-editors */
2790     ourname = cond_type == ECOND_BOOL_LAX ? US"bool_lax" : US"bool";
2791     switch(read_subs(sub_arg, 1, 1, &s, yield == NULL, FALSE, ourname))
2792       {
2793       case 1: expand_string_message = string_sprintf(
2794                   "too few arguments or bracketing error for %s",
2795                   ourname);
2796       /*FALLTHROUGH*/
2797       case 2:
2798       case 3: return NULL;
2799       }
2800     t = sub_arg[0];
2801     while (isspace(*t)) t++;
2802     len = Ustrlen(t);
2803     if (len)
2804       {
2805       /* trailing whitespace: seems like a good idea to ignore it too */
2806       t2 = t + len - 1;
2807       while (isspace(*t2)) t2--;
2808       if (t2 != (t + len))
2809         {
2810         *++t2 = '\0';
2811         len = t2 - t;
2812         }
2813       }
2814     DEBUG(D_expand)
2815       debug_printf("considering %s: %s\n", ourname, len ? t : US"<empty>");
2816     /* logic for the lax case from expand_check_condition(), which also does
2817     expands, and the logic is both short and stable enough that there should
2818     be no maintenance burden from replicating it. */
2819     if (len == 0)
2820       boolvalue = FALSE;
2821     else if (Ustrspn(t, "0123456789") == len)
2822       {
2823       boolvalue = (Uatoi(t) == 0) ? FALSE : TRUE;
2824       /* expand_check_condition only does a literal string "0" check */
2825       if ((cond_type == ECOND_BOOL_LAX) && (len > 1))
2826         boolvalue = TRUE;
2827       }
2828     else if (strcmpic(t, US"true") == 0 || strcmpic(t, US"yes") == 0)
2829       boolvalue = TRUE;
2830     else if (strcmpic(t, US"false") == 0 || strcmpic(t, US"no") == 0)
2831       boolvalue = FALSE;
2832     else if (cond_type == ECOND_BOOL_LAX)
2833       boolvalue = TRUE;
2834     else
2835       {
2836       expand_string_message = string_sprintf("unrecognised boolean "
2837        "value \"%s\"", t);
2838       return NULL;
2839       }
2840     if (yield != NULL) *yield = (boolvalue == testfor);
2841     return s;
2842     }
2843
2844   /* Unknown condition */
2845
2846   default:
2847   expand_string_message = string_sprintf("unknown condition \"%s\"", name);
2848   return NULL;
2849   }   /* End switch on condition type */
2850
2851 /* Missing braces at start and end of data */
2852
2853 COND_FAILED_CURLY_START:
2854 expand_string_message = string_sprintf("missing { after \"%s\"", name);
2855 return NULL;
2856
2857 COND_FAILED_CURLY_END:
2858 expand_string_message = string_sprintf("missing } at end of \"%s\" condition",
2859   name);
2860 return NULL;
2861
2862 /* A condition requires code that is not compiled */
2863
2864 #if !defined(SUPPORT_PAM) || !defined(RADIUS_CONFIG_FILE) || \
2865     !defined(LOOKUP_LDAP) || !defined(CYRUS_PWCHECK_SOCKET) || \
2866     !defined(SUPPORT_CRYPTEQ) || !defined(CYRUS_SASLAUTHD_SOCKET)
2867 COND_FAILED_NOT_COMPILED:
2868 expand_string_message = string_sprintf("support for \"%s\" not compiled",
2869   name);
2870 return NULL;
2871 #endif
2872 }
2873
2874
2875
2876
2877 /*************************************************
2878 *          Save numerical variables              *
2879 *************************************************/
2880
2881 /* This function is called from items such as "if" that want to preserve and
2882 restore the numbered variables.
2883
2884 Arguments:
2885   save_expand_string    points to an array of pointers to set
2886   save_expand_nlength   points to an array of ints for the lengths
2887
2888 Returns:                the value of expand max to save
2889 */
2890
2891 static int
2892 save_expand_strings(uschar **save_expand_nstring, int *save_expand_nlength)
2893 {
2894 int i;
2895 for (i = 0; i <= expand_nmax; i++)
2896   {
2897   save_expand_nstring[i] = expand_nstring[i];
2898   save_expand_nlength[i] = expand_nlength[i];
2899   }
2900 return expand_nmax;
2901 }
2902
2903
2904
2905 /*************************************************
2906 *           Restore numerical variables          *
2907 *************************************************/
2908
2909 /* This function restored saved values of numerical strings.
2910
2911 Arguments:
2912   save_expand_nmax      the number of strings to restore
2913   save_expand_string    points to an array of pointers
2914   save_expand_nlength   points to an array of ints
2915
2916 Returns:                nothing
2917 */
2918
2919 static void
2920 restore_expand_strings(int save_expand_nmax, uschar **save_expand_nstring,
2921   int *save_expand_nlength)
2922 {
2923 int i;
2924 expand_nmax = save_expand_nmax;
2925 for (i = 0; i <= expand_nmax; i++)
2926   {
2927   expand_nstring[i] = save_expand_nstring[i];
2928   expand_nlength[i] = save_expand_nlength[i];
2929   }
2930 }
2931
2932
2933
2934
2935
2936 /*************************************************
2937 *            Handle yes/no substrings            *
2938 *************************************************/
2939
2940 /* This function is used by ${if}, ${lookup} and ${extract} to handle the
2941 alternative substrings that depend on whether or not the condition was true,
2942 or the lookup or extraction succeeded. The substrings always have to be
2943 expanded, to check their syntax, but "skipping" is set when the result is not
2944 needed - this avoids unnecessary nested lookups.
2945
2946 Arguments:
2947   skipping       TRUE if we were skipping when this item was reached
2948   yes            TRUE if the first string is to be used, else use the second
2949   save_lookup    a value to put back into lookup_value before the 2nd expansion
2950   sptr           points to the input string pointer
2951   yieldptr       points to the output string pointer
2952   sizeptr        points to the output string size
2953   ptrptr         points to the output string pointer
2954   type           "lookup" or "if" or "extract" or "run", for error message
2955
2956 Returns:         0 OK; lookup_value has been reset to save_lookup
2957                  1 expansion failed
2958                  2 expansion failed because of bracketing error
2959 */
2960
2961 static int
2962 process_yesno(BOOL skipping, BOOL yes, uschar *save_lookup, uschar **sptr,
2963   uschar **yieldptr, int *sizeptr, int *ptrptr, uschar *type)
2964 {
2965 int rc = 0;
2966 uschar *s = *sptr;    /* Local value */
2967 uschar *sub1, *sub2;
2968
2969 /* If there are no following strings, we substitute the contents of $value for
2970 lookups and for extractions in the success case. For the ${if item, the string
2971 "true" is substituted. In the fail case, nothing is substituted for all three
2972 items. */
2973
2974 while (isspace(*s)) s++;
2975 if (*s == '}')
2976   {
2977   if (type[0] == 'i')
2978     {
2979     if (yes) *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, US"true", 4);
2980     }
2981   else
2982     {
2983     if (yes && lookup_value != NULL)
2984       *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, lookup_value,
2985         Ustrlen(lookup_value));
2986     lookup_value = save_lookup;
2987     }
2988   s++;
2989   goto RETURN;
2990   }
2991
2992 /* The first following string must be braced. */
2993
2994 if (*s++ != '{') goto FAILED_CURLY;
2995
2996 /* Expand the first substring. Forced failures are noticed only if we actually
2997 want this string. Set skipping in the call in the fail case (this will always
2998 be the case if we were already skipping). */
2999
3000 sub1 = expand_string_internal(s, TRUE, &s, !yes, TRUE);
3001 if (sub1 == NULL && (yes || !expand_string_forcedfail)) goto FAILED;
3002 expand_string_forcedfail = FALSE;
3003 if (*s++ != '}') goto FAILED_CURLY;
3004
3005 /* If we want the first string, add it to the output */
3006
3007 if (yes)
3008   *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, sub1, Ustrlen(sub1));
3009
3010 /* If this is called from a lookup or an extract, we want to restore $value to
3011 what it was at the start of the item, so that it has this value during the
3012 second string expansion. For the call from "if" or "run" to this function,
3013 save_lookup is set to lookup_value, so that this statement does nothing. */
3014
3015 lookup_value = save_lookup;
3016
3017 /* There now follows either another substring, or "fail", or nothing. This
3018 time, forced failures are noticed only if we want the second string. We must
3019 set skipping in the nested call if we don't want this string, or if we were
3020 already skipping. */
3021
3022 while (isspace(*s)) s++;
3023 if (*s == '{')
3024   {
3025   sub2 = expand_string_internal(s+1, TRUE, &s, yes || skipping, TRUE);
3026   if (sub2 == NULL && (!yes || !expand_string_forcedfail)) goto FAILED;
3027   expand_string_forcedfail = FALSE;
3028   if (*s++ != '}') goto FAILED_CURLY;
3029
3030   /* If we want the second string, add it to the output */
3031
3032   if (!yes)
3033     *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, sub2, Ustrlen(sub2));
3034   }
3035
3036 /* If there is no second string, but the word "fail" is present when the use of
3037 the second string is wanted, set a flag indicating it was a forced failure
3038 rather than a syntactic error. Swallow the terminating } in case this is nested
3039 inside another lookup or if or extract. */
3040
3041 else if (*s != '}')
3042   {
3043   uschar name[256];
3044   s = read_name(name, sizeof(name), s, US"_");
3045   if (Ustrcmp(name, "fail") == 0)
3046     {
3047     if (!yes && !skipping)
3048       {
3049       while (isspace(*s)) s++;
3050       if (*s++ != '}') goto FAILED_CURLY;
3051       expand_string_message =
3052         string_sprintf("\"%s\" failed and \"fail\" requested", type);
3053       expand_string_forcedfail = TRUE;
3054       goto FAILED;
3055       }
3056     }
3057   else
3058     {
3059     expand_string_message =
3060       string_sprintf("syntax error in \"%s\" item - \"fail\" expected", type);
3061     goto FAILED;
3062     }
3063   }
3064
3065 /* All we have to do now is to check on the final closing brace. */
3066
3067 while (isspace(*s)) s++;
3068 if (*s++ == '}') goto RETURN;
3069
3070 /* Get here if there is a bracketing failure */
3071
3072 FAILED_CURLY:
3073 rc++;
3074
3075 /* Get here for other failures */
3076
3077 FAILED:
3078 rc++;
3079
3080 /* Update the input pointer value before returning */
3081
3082 RETURN:
3083 *sptr = s;
3084 return rc;
3085 }
3086
3087
3088
3089
3090 /*************************************************
3091 *    Handle MD5 or SHA-1 computation for HMAC    *
3092 *************************************************/
3093
3094 /* These are some wrapping functions that enable the HMAC code to be a bit
3095 cleaner. A good compiler will spot the tail recursion.
3096
3097 Arguments:
3098   type         HMAC_MD5 or HMAC_SHA1
3099   remaining    are as for the cryptographic hash functions
3100
3101 Returns:       nothing
3102 */
3103
3104 static void
3105 chash_start(int type, void *base)
3106 {
3107 if (type == HMAC_MD5)
3108   md5_start((md5 *)base);
3109 else
3110   sha1_start((sha1 *)base);
3111 }
3112
3113 static void
3114 chash_mid(int type, void *base, uschar *string)
3115 {
3116 if (type == HMAC_MD5)
3117   md5_mid((md5 *)base, string);
3118 else
3119   sha1_mid((sha1 *)base, string);
3120 }
3121
3122 static void
3123 chash_end(int type, void *base, uschar *string, int length, uschar *digest)
3124 {
3125 if (type == HMAC_MD5)
3126   md5_end((md5 *)base, string, length, digest);
3127 else
3128   sha1_end((sha1 *)base, string, length, digest);
3129 }
3130
3131
3132
3133
3134
3135 /********************************************************
3136 * prvs: Get last three digits of days since Jan 1, 1970 *
3137 ********************************************************/
3138
3139 /* This is needed to implement the "prvs" BATV reverse
3140    path signing scheme
3141
3142 Argument: integer "days" offset to add or substract to
3143           or from the current number of days.
3144
3145 Returns:  pointer to string containing the last three
3146           digits of the number of days since Jan 1, 1970,
3147           modified by the offset argument, NULL if there
3148           was an error in the conversion.
3149
3150 */
3151
3152 static uschar *
3153 prvs_daystamp(int day_offset)
3154 {
3155 uschar *days = store_get(32);                /* Need at least 24 for cases */
3156 (void)string_format(days, 32, TIME_T_FMT,    /* where TIME_T_FMT is %lld */
3157   (time(NULL) + day_offset*86400)/86400);
3158 return (Ustrlen(days) >= 3) ? &days[Ustrlen(days)-3] : US"100";
3159 }
3160
3161
3162
3163 /********************************************************
3164 *   prvs: perform HMAC-SHA1 computation of prvs bits    *
3165 ********************************************************/
3166
3167 /* This is needed to implement the "prvs" BATV reverse
3168    path signing scheme
3169
3170 Arguments:
3171   address RFC2821 Address to use
3172       key The key to use (must be less than 64 characters
3173           in size)
3174   key_num Single-digit key number to use. Defaults to
3175           '0' when NULL.
3176
3177 Returns:  pointer to string containing the first three
3178           bytes of the final hash in hex format, NULL if
3179           there was an error in the process.
3180 */
3181
3182 static uschar *
3183 prvs_hmac_sha1(uschar *address, uschar *key, uschar *key_num, uschar *daystamp)
3184 {
3185 uschar *hash_source, *p;
3186 int size = 0,offset = 0,i;
3187 sha1 sha1_base;
3188 void *use_base = &sha1_base;
3189 uschar innerhash[20];
3190 uschar finalhash[20];
3191 uschar innerkey[64];
3192 uschar outerkey[64];
3193 uschar *finalhash_hex = store_get(40);
3194
3195 if (key_num == NULL)
3196   key_num = US"0";
3197
3198 if (Ustrlen(key) > 64)
3199   return NULL;
3200
3201 hash_source = string_cat(NULL,&size,&offset,key_num,1);
3202 string_cat(hash_source,&size,&offset,daystamp,3);
3203 string_cat(hash_source,&size,&offset,address,Ustrlen(address));
3204 hash_source[offset] = '\0';
3205
3206 DEBUG(D_expand) debug_printf("prvs: hash source is '%s'\n", hash_source);
3207
3208 memset(innerkey, 0x36, 64);
3209 memset(outerkey, 0x5c, 64);
3210
3211 for (i = 0; i < Ustrlen(key); i++)
3212   {
3213   innerkey[i] ^= key[i];
3214   outerkey[i] ^= key[i];
3215   }
3216
3217 chash_start(HMAC_SHA1, use_base);
3218 chash_mid(HMAC_SHA1, use_base, innerkey);
3219 chash_end(HMAC_SHA1, use_base, hash_source, offset, innerhash);
3220
3221 chash_start(HMAC_SHA1, use_base);
3222 chash_mid(HMAC_SHA1, use_base, outerkey);
3223 chash_end(HMAC_SHA1, use_base, innerhash, 20, finalhash);
3224
3225 p = finalhash_hex;
3226 for (i = 0; i < 3; i++)
3227   {
3228   *p++ = hex_digits[(finalhash[i] & 0xf0) >> 4];
3229   *p++ = hex_digits[finalhash[i] & 0x0f];
3230   }
3231 *p = '\0';
3232
3233 return finalhash_hex;
3234 }
3235
3236
3237
3238
3239 /*************************************************
3240 *        Join a file onto the output string      *
3241 *************************************************/
3242
3243 /* This is used for readfile and after a run expansion. It joins the contents
3244 of a file onto the output string, globally replacing newlines with a given
3245 string (optionally). The file is closed at the end.
3246
3247 Arguments:
3248   f            the FILE
3249   yield        pointer to the expandable string
3250   sizep        pointer to the current size
3251   ptrp         pointer to the current position
3252   eol          newline replacement string, or NULL
3253
3254 Returns:       new value of string pointer
3255 */
3256
3257 static uschar *
3258 cat_file(FILE *f, uschar *yield, int *sizep, int *ptrp, uschar *eol)
3259 {
3260 int eollen;
3261 uschar buffer[1024];
3262
3263 eollen = (eol == NULL)? 0 : Ustrlen(eol);
3264
3265 while (Ufgets(buffer, sizeof(buffer), f) != NULL)
3266   {
3267   int len = Ustrlen(buffer);
3268   if (eol != NULL && buffer[len-1] == '\n') len--;
3269   yield = string_cat(yield, sizep, ptrp, buffer, len);
3270   if (buffer[len] != 0)
3271     yield = string_cat(yield, sizep, ptrp, eol, eollen);
3272   }
3273
3274 if (yield != NULL) yield[*ptrp] = 0;
3275
3276 return yield;
3277 }
3278
3279
3280
3281
3282 /*************************************************
3283 *          Evaluate numeric expression           *
3284 *************************************************/
3285
3286 /* This is a set of mutually recursive functions that evaluate an arithmetic
3287 expression involving + - * / % & | ^ ~ << >> and parentheses. The only one of
3288 these functions that is called from elsewhere is eval_expr, whose interface is:
3289
3290 Arguments:
3291   sptr        pointer to the pointer to the string - gets updated
3292   decimal     TRUE if numbers are to be assumed decimal
3293   error       pointer to where to put an error message - must be NULL on input
3294   endket      TRUE if ')' must terminate - FALSE for external call
3295
3296 Returns:      on success: the value of the expression, with *error still NULL
3297               on failure: an undefined value, with *error = a message
3298 */
3299
3300 static int_eximarith_t eval_op_or(uschar **, BOOL, uschar **);
3301
3302
3303 static int_eximarith_t
3304 eval_expr(uschar **sptr, BOOL decimal, uschar **error, BOOL endket)
3305 {
3306 uschar *s = *sptr;
3307 int_eximarith_t x = eval_op_or(&s, decimal, error);
3308 if (*error == NULL)
3309   {
3310   if (endket)
3311     {
3312     if (*s != ')')
3313       *error = US"expecting closing parenthesis";
3314     else
3315       while (isspace(*(++s)));
3316     }
3317   else if (*s != 0) *error = US"expecting operator";
3318   }
3319 *sptr = s;
3320 return x;
3321 }
3322
3323
3324 static int_eximarith_t
3325 eval_number(uschar **sptr, BOOL decimal, uschar **error)
3326 {
3327 register int c;
3328 int_eximarith_t n;
3329 uschar *s = *sptr;
3330 while (isspace(*s)) s++;
3331 c = *s;
3332 if (isdigit(c))
3333   {
3334   int count;
3335   (void)sscanf(CS s, (decimal? SC_EXIM_DEC "%n" : SC_EXIM_ARITH "%n"), &n, &count);
3336   s += count;
3337   switch (tolower(*s))
3338     {
3339     default: break;
3340     case 'k': n *= 1024; s++; break;
3341     case 'm': n *= 1024*1024; s++; break;
3342     case 'g': n *= 1024*1024*1024; s++; break;
3343     }
3344   while (isspace (*s)) s++;
3345   }
3346 else if (c == '(')
3347   {
3348   s++;
3349   n = eval_expr(&s, decimal, error, 1);
3350   }
3351 else
3352   {
3353   *error = US"expecting number or opening parenthesis";
3354   n = 0;
3355   }
3356 *sptr = s;
3357 return n;
3358 }
3359
3360
3361 static int_eximarith_t
3362 eval_op_unary(uschar **sptr, BOOL decimal, uschar **error)
3363 {
3364 uschar *s = *sptr;
3365 int_eximarith_t x;
3366 while (isspace(*s)) s++;
3367 if (*s == '+' || *s == '-' || *s == '~')
3368   {
3369   int op = *s++;
3370   x = eval_op_unary(&s, decimal, error);
3371   if (op == '-') x = -x;
3372     else if (op == '~') x = ~x;
3373   }
3374 else
3375   {
3376   x = eval_number(&s, decimal, error);
3377   }
3378 *sptr = s;
3379 return x;
3380 }
3381
3382
3383 static int_eximarith_t
3384 eval_op_mult(uschar **sptr, BOOL decimal, uschar **error)
3385 {
3386 uschar *s = *sptr;
3387 int_eximarith_t x = eval_op_unary(&s, decimal, error);
3388 if (*error == NULL)
3389   {
3390   while (*s == '*' || *s == '/' || *s == '%')
3391     {
3392     int op = *s++;
3393     int_eximarith_t y = eval_op_unary(&s, decimal, error);
3394     if (*error != NULL) break;
3395     /* SIGFPE both on div/mod by zero and on INT_MIN / -1, which would give
3396      * a value of INT_MAX+1. Note that INT_MIN * -1 gives INT_MIN for me, which
3397      * is a bug somewhere in [gcc 4.2.1, FreeBSD, amd64].  In fact, -N*-M where
3398      * -N*M is INT_MIN will yielf INT_MIN.
3399      * Since we don't support floating point, this is somewhat simpler.
3400      * Ideally, we'd return an error, but since we overflow for all other
3401      * arithmetic, consistency suggests otherwise, but what's the correct value
3402      * to use?  There is none.
3403      * The C standard guarantees overflow for unsigned arithmetic but signed
3404      * overflow invokes undefined behaviour; in practice, this is overflow
3405      * except for converting INT_MIN to INT_MAX+1.  We also can't guarantee
3406      * that long/longlong larger than int are available, or we could just work
3407      * with larger types.  We should consider whether to guarantee 32bit eval
3408      * and 64-bit working variables, with errors returned.  For now ...
3409      * So, the only SIGFPEs occur with a non-shrinking div/mod, thus -1; we
3410      * can just let the other invalid results occur otherwise, as they have
3411      * until now.  For this one case, we can coerce.
3412      */
3413     if (y == -1 && x == EXIM_ARITH_MIN && op != '*')
3414       {
3415       DEBUG(D_expand)
3416         debug_printf("Integer exception dodging: " PR_EXIM_ARITH "%c-1 coerced to " PR_EXIM_ARITH "\n",
3417             EXIM_ARITH_MIN, op, EXIM_ARITH_MAX);
3418       x = EXIM_ARITH_MAX;
3419       continue;
3420       }
3421     if (op == '*')
3422       x *= y;
3423     else
3424       {
3425       if (y == 0)
3426         {
3427         *error = (op == '/') ? US"divide by zero" : US"modulo by zero";
3428         x = 0;
3429         break;
3430         }
3431       if (op == '/')
3432         x /= y;
3433       else
3434         x %= y;
3435       }
3436     }
3437   }
3438 *sptr = s;
3439 return x;
3440 }
3441
3442
3443 static int_eximarith_t
3444 eval_op_sum(uschar **sptr, BOOL decimal, uschar **error)
3445 {
3446 uschar *s = *sptr;
3447 int_eximarith_t x = eval_op_mult(&s, decimal, error);
3448 if (*error == NULL)
3449   {
3450   while (*s == '+' || *s == '-')
3451     {
3452     int op = *s++;
3453     int_eximarith_t y = eval_op_mult(&s, decimal, error);
3454     if (*error != NULL) break;
3455     if (op == '+') x += y; else x -= y;
3456     }
3457   }
3458 *sptr = s;
3459 return x;
3460 }
3461
3462
3463 static int_eximarith_t
3464 eval_op_shift(uschar **sptr, BOOL decimal, uschar **error)
3465 {
3466 uschar *s = *sptr;
3467 int_eximarith_t x = eval_op_sum(&s, decimal, error);
3468 if (*error == NULL)
3469   {
3470   while ((*s == '<' || *s == '>') && s[1] == s[0])
3471     {
3472     int_eximarith_t y;
3473     int op = *s++;
3474     s++;
3475     y = eval_op_sum(&s, decimal, error);
3476     if (*error != NULL) break;
3477     if (op == '<') x <<= y; else x >>= y;
3478     }
3479   }
3480 *sptr = s;
3481 return x;
3482 }
3483
3484
3485 static int_eximarith_t
3486 eval_op_and(uschar **sptr, BOOL decimal, uschar **error)
3487 {
3488 uschar *s = *sptr;
3489 int_eximarith_t x = eval_op_shift(&s, decimal, error);
3490 if (*error == NULL)
3491   {
3492   while (*s == '&')
3493     {
3494     int_eximarith_t y;
3495     s++;
3496     y = eval_op_shift(&s, decimal, error);
3497     if (*error != NULL) break;
3498     x &= y;
3499     }
3500   }
3501 *sptr = s;
3502 return x;
3503 }
3504
3505
3506 static int_eximarith_t
3507 eval_op_xor(uschar **sptr, BOOL decimal, uschar **error)
3508 {
3509 uschar *s = *sptr;
3510 int_eximarith_t x = eval_op_and(&s, decimal, error);
3511 if (*error == NULL)
3512   {
3513   while (*s == '^')
3514     {
3515     int_eximarith_t y;
3516     s++;
3517     y = eval_op_and(&s, decimal, error);
3518     if (*error != NULL) break;
3519     x ^= y;
3520     }
3521   }
3522 *sptr = s;
3523 return x;
3524 }
3525
3526
3527 static int_eximarith_t
3528 eval_op_or(uschar **sptr, BOOL decimal, uschar **error)
3529 {
3530 uschar *s = *sptr;
3531 int_eximarith_t x = eval_op_xor(&s, decimal, error);
3532 if (*error == NULL)
3533   {
3534   while (*s == '|')
3535     {
3536     int_eximarith_t y;
3537     s++;
3538     y = eval_op_xor(&s, decimal, error);
3539     if (*error != NULL) break;
3540     x |= y;
3541     }
3542   }
3543 *sptr = s;
3544 return x;
3545 }
3546
3547
3548
3549 /*************************************************
3550 *                 Expand string                  *
3551 *************************************************/
3552
3553 /* Returns either an unchanged string, or the expanded string in stacking pool
3554 store. Interpreted sequences are:
3555
3556    \...                    normal escaping rules
3557    $name                   substitutes the variable
3558    ${name}                 ditto
3559    ${op:string}            operates on the expanded string value
3560    ${item{arg1}{arg2}...}  expands the args and then does the business
3561                              some literal args are not enclosed in {}
3562
3563 There are now far too many operators and item types to make it worth listing
3564 them here in detail any more.
3565
3566 We use an internal routine recursively to handle embedded substrings. The
3567 external function follows. The yield is NULL if the expansion failed, and there
3568 are two cases: if something collapsed syntactically, or if "fail" was given
3569 as the action on a lookup failure. These can be distinguised by looking at the
3570 variable expand_string_forcedfail, which is TRUE in the latter case.
3571
3572 The skipping flag is set true when expanding a substring that isn't actually
3573 going to be used (after "if" or "lookup") and it prevents lookups from
3574 happening lower down.
3575
3576 Store usage: At start, a store block of the length of the input plus 64
3577 is obtained. This is expanded as necessary by string_cat(), which might have to
3578 get a new block, or might be able to expand the original. At the end of the
3579 function we can release any store above that portion of the yield block that
3580 was actually used. In many cases this will be optimal.
3581
3582 However: if the first item in the expansion is a variable name or header name,
3583 we reset the store before processing it; if the result is in fresh store, we
3584 use that without copying. This is helpful for expanding strings like
3585 $message_headers which can get very long.
3586
3587 There's a problem if a ${dlfunc item has side-effects that cause allocation,
3588 since resetting the store at the end of the expansion will free store that was
3589 allocated by the plugin code as well as the slop after the expanded string. So
3590 we skip any resets if ${dlfunc has been used. The same applies for ${acl. This
3591 is an unfortunate consequence of string expansion becoming too powerful.
3592
3593 Arguments:
3594   string         the string to be expanded
3595   ket_ends       true if expansion is to stop at }
3596   left           if not NULL, a pointer to the first character after the
3597                  expansion is placed here (typically used with ket_ends)
3598   skipping       TRUE for recursive calls when the value isn't actually going
3599                  to be used (to allow for optimisation)
3600   honour_dollar  TRUE if $ is to be expanded,
3601                  FALSE if it's just another character
3602
3603 Returns:         NULL if expansion fails:
3604                    expand_string_forcedfail is set TRUE if failure was forced
3605                    expand_string_message contains a textual error message
3606                  a pointer to the expanded string on success
3607 */
3608
3609 static uschar *
3610 expand_string_internal(uschar *string, BOOL ket_ends, uschar **left,
3611   BOOL skipping, BOOL honour_dollar)
3612 {
3613 int ptr = 0;
3614 int size = Ustrlen(string)+ 64;
3615 int item_type;
3616 uschar *yield = store_get(size);
3617 uschar *s = string;
3618 uschar *save_expand_nstring[EXPAND_MAXN+1];
3619 int save_expand_nlength[EXPAND_MAXN+1];
3620 BOOL resetok = TRUE;
3621
3622 expand_string_forcedfail = FALSE;
3623 expand_string_message = US"";
3624
3625 while (*s != 0)
3626   {
3627   uschar *value;
3628   uschar name[256];
3629
3630   /* \ escapes the next character, which must exist, or else
3631   the expansion fails. There's a special escape, \N, which causes
3632   copying of the subject verbatim up to the next \N. Otherwise,
3633   the escapes are the standard set. */
3634
3635   if (*s == '\\')
3636     {
3637     if (s[1] == 0)
3638       {
3639       expand_string_message = US"\\ at end of string";
3640       goto EXPAND_FAILED;
3641       }
3642
3643     if (s[1] == 'N')
3644       {
3645       uschar *t = s + 2;
3646       for (s = t; *s != 0; s++) if (*s == '\\' && s[1] == 'N') break;
3647       yield = string_cat(yield, &size, &ptr, t, s - t);
3648       if (*s != 0) s += 2;
3649       }
3650
3651     else
3652       {
3653       uschar ch[1];
3654       ch[0] = string_interpret_escape(&s);
3655       s++;
3656       yield = string_cat(yield, &size, &ptr, ch, 1);
3657       }
3658
3659     continue;
3660     }
3661
3662   /*{*/
3663   /* Anything other than $ is just copied verbatim, unless we are
3664   looking for a terminating } character. */
3665
3666   /*{*/
3667   if (ket_ends && *s == '}') break;
3668
3669   if (*s != '$' || !honour_dollar)
3670     {
3671     yield = string_cat(yield, &size, &ptr, s++, 1);
3672     continue;
3673     }
3674
3675   /* No { after the $ - must be a plain name or a number for string
3676   match variable. There has to be a fudge for variables that are the
3677   names of header fields preceded by "$header_" because header field
3678   names can contain any printing characters except space and colon.
3679   For those that don't like typing this much, "$h_" is a synonym for
3680   "$header_". A non-existent header yields a NULL value; nothing is
3681   inserted. */  /*}*/
3682
3683   if (isalpha((*(++s))))
3684     {
3685     int len;
3686     int newsize = 0;
3687
3688     s = read_name(name, sizeof(name), s, US"_");
3689
3690     /* If this is the first thing to be expanded, release the pre-allocated
3691     buffer. */
3692
3693     if (ptr == 0 && yield != NULL)
3694       {
3695       if (resetok) store_reset(yield);
3696       yield = NULL;
3697       size = 0;
3698       }
3699
3700     /* Header */
3701
3702     if (Ustrncmp(name, "h_", 2) == 0 ||
3703         Ustrncmp(name, "rh_", 3) == 0 ||
3704         Ustrncmp(name, "bh_", 3) == 0 ||
3705         Ustrncmp(name, "header_", 7) == 0 ||
3706         Ustrncmp(name, "rheader_", 8) == 0 ||
3707         Ustrncmp(name, "bheader_", 8) == 0)
3708       {
3709       BOOL want_raw = (name[0] == 'r')? TRUE : FALSE;
3710       uschar *charset = (name[0] == 'b')? NULL : headers_charset;
3711       s = read_header_name(name, sizeof(name), s);
3712       value = find_header(name, FALSE, &newsize, want_raw, charset);
3713
3714       /* If we didn't find the header, and the header contains a closing brace
3715       character, this may be a user error where the terminating colon
3716       has been omitted. Set a flag to adjust the error message in this case.
3717       But there is no error here - nothing gets inserted. */
3718
3719       if (value == NULL)
3720         {
3721         if (Ustrchr(name, '}') != NULL) malformed_header = TRUE;
3722         continue;
3723         }
3724       }
3725
3726     /* Variable */
3727
3728     else
3729       {
3730       value = find_variable(name, FALSE, skipping, &newsize);
3731       if (value == NULL)
3732         {
3733         expand_string_message =
3734           string_sprintf("unknown variable name \"%s\"", name);
3735           check_variable_error_message(name);
3736         goto EXPAND_FAILED;
3737         }
3738       }
3739
3740     /* If the data is known to be in a new buffer, newsize will be set to the
3741     size of that buffer. If this is the first thing in an expansion string,
3742     yield will be NULL; just point it at the new store instead of copying. Many
3743     expansion strings contain just one reference, so this is a useful
3744     optimization, especially for humungous headers. */
3745
3746     len = Ustrlen(value);
3747     if (yield == NULL && newsize != 0)
3748       {
3749       yield = value;
3750       size = newsize;
3751       ptr = len;
3752       }
3753     else yield = string_cat(yield, &size, &ptr, value, len);
3754
3755     continue;
3756     }
3757
3758   if (isdigit(*s))
3759     {
3760     int n;
3761     s = read_number(&n, s);
3762     if (n >= 0 && n <= expand_nmax)
3763       yield = string_cat(yield, &size, &ptr, expand_nstring[n],
3764         expand_nlength[n]);
3765     continue;
3766     }
3767
3768   /* Otherwise, if there's no '{' after $ it's an error. */             /*}*/
3769
3770   if (*s != '{')                                                        /*}*/
3771     {
3772     expand_string_message = US"$ not followed by letter, digit, or {";  /*}*/
3773     goto EXPAND_FAILED;
3774     }
3775
3776   /* After { there can be various things, but they all start with
3777   an initial word, except for a number for a string match variable. */
3778
3779   if (isdigit((*(++s))))
3780     {
3781     int n;
3782     s = read_number(&n, s);             /*{*/
3783     if (*s++ != '}')
3784       {                                 /*{*/
3785       expand_string_message = US"} expected after number";
3786       goto EXPAND_FAILED;
3787       }
3788     if (n >= 0 && n <= expand_nmax)
3789       yield = string_cat(yield, &size, &ptr, expand_nstring[n],
3790         expand_nlength[n]);
3791     continue;
3792     }
3793
3794   if (!isalpha(*s))
3795     {
3796     expand_string_message = US"letter or digit expected after ${";      /*}*/
3797     goto EXPAND_FAILED;
3798     }
3799
3800   /* Allow "-" in names to cater for substrings with negative
3801   arguments. Since we are checking for known names after { this is
3802   OK. */
3803
3804   s = read_name(name, sizeof(name), s, US"_-");
3805   item_type = chop_match(name, item_table, sizeof(item_table)/sizeof(uschar *));
3806
3807   switch(item_type)
3808     {
3809     /* Call an ACL from an expansion.  We feed data in via $acl_arg1 - $acl_arg9.
3810     If the ACL returns accept or reject we return content set by "message ="
3811     There is currently no limit on recursion; this would have us call
3812     acl_check_internal() directly and get a current level from somewhere.
3813     See also the acl expansion condition ECOND_ACL and the traditional
3814     acl modifier ACLC_ACL.
3815     Assume that the function has side-effects on the store that must be preserved.
3816     */
3817
3818     case EITEM_ACL:
3819       /* ${acl {name} {arg1}{arg2}...} */
3820       {
3821       uschar *sub[10];  /* name + arg1-arg9 (which must match number of acl_arg[]) */
3822       uschar *user_msg;
3823
3824       switch(read_subs(sub, 10, 1, &s, skipping, TRUE, US"acl"))
3825         {
3826         case 1: goto EXPAND_FAILED_CURLY;
3827         case 2:
3828         case 3: goto EXPAND_FAILED;
3829         }
3830       if (skipping) continue;
3831
3832       resetok = FALSE;
3833       switch(eval_acl(sub, sizeof(sub)/sizeof(*sub), &user_msg))
3834         {
3835         case OK:
3836         case FAIL:
3837           if (user_msg)
3838             yield = string_cat(yield, &size, &ptr, user_msg, Ustrlen(user_msg));
3839           continue;
3840
3841         case DEFER:
3842           expand_string_forcedfail = TRUE;
3843         default:
3844           expand_string_message = string_sprintf("error from acl \"%s\"", sub[0]);
3845           goto EXPAND_FAILED;
3846         }
3847       }
3848
3849     /* Handle conditionals - preserve the values of the numerical expansion
3850     variables in case they get changed by a regular expression match in the
3851     condition. If not, they retain their external settings. At the end
3852     of this "if" section, they get restored to their previous values. */
3853
3854     case EITEM_IF:
3855       {
3856       BOOL cond = FALSE;
3857       uschar *next_s;
3858       int save_expand_nmax =
3859         save_expand_strings(save_expand_nstring, save_expand_nlength);
3860
3861       while (isspace(*s)) s++;
3862       next_s = eval_condition(s, skipping? NULL : &cond);
3863       if (next_s == NULL) goto EXPAND_FAILED;  /* message already set */
3864
3865       DEBUG(D_expand)
3866         debug_printf("condition: %.*s\n   result: %s\n", (int)(next_s - s), s,
3867           cond? "true" : "false");
3868
3869       s = next_s;
3870
3871       /* The handling of "yes" and "no" result strings is now in a separate
3872       function that is also used by ${lookup} and ${extract} and ${run}. */
3873
3874       switch(process_yesno(
3875                skipping,                     /* were previously skipping */
3876                cond,                         /* success/failure indicator */
3877                lookup_value,                 /* value to reset for string2 */
3878                &s,                           /* input pointer */
3879                &yield,                       /* output pointer */
3880                &size,                        /* output size */
3881                &ptr,                         /* output current point */
3882                US"if"))                      /* condition type */
3883         {
3884         case 1: goto EXPAND_FAILED;          /* when all is well, the */
3885         case 2: goto EXPAND_FAILED_CURLY;    /* returned value is 0 */
3886         }
3887
3888       /* Restore external setting of expansion variables for continuation
3889       at this level. */
3890
3891       restore_expand_strings(save_expand_nmax, save_expand_nstring,
3892         save_expand_nlength);
3893       continue;
3894       }
3895
3896     /* Handle database lookups unless locked out. If "skipping" is TRUE, we are
3897     expanding an internal string that isn't actually going to be used. All we
3898     need to do is check the syntax, so don't do a lookup at all. Preserve the
3899     values of the numerical expansion variables in case they get changed by a
3900     partial lookup. If not, they retain their external settings. At the end
3901     of this "lookup" section, they get restored to their previous values. */
3902
3903     case EITEM_LOOKUP:
3904       {
3905       int stype, partial, affixlen, starflags;
3906       int expand_setup = 0;
3907       int nameptr = 0;
3908       uschar *key, *filename, *affix;
3909       uschar *save_lookup_value = lookup_value;
3910       int save_expand_nmax =
3911         save_expand_strings(save_expand_nstring, save_expand_nlength);
3912
3913       if ((expand_forbid & RDO_LOOKUP) != 0)
3914         {
3915         expand_string_message = US"lookup expansions are not permitted";
3916         goto EXPAND_FAILED;
3917         }
3918
3919       /* Get the key we are to look up for single-key+file style lookups.
3920       Otherwise set the key NULL pro-tem. */
3921
3922       while (isspace(*s)) s++;
3923       if (*s == '{')                                    /*}*/
3924         {
3925         key = expand_string_internal(s+1, TRUE, &s, skipping, TRUE);
3926         if (key == NULL) goto EXPAND_FAILED;            /*{*/
3927         if (*s++ != '}') goto EXPAND_FAILED_CURLY;
3928         while (isspace(*s)) s++;
3929         }
3930       else key = NULL;
3931
3932       /* Find out the type of database */
3933
3934       if (!isalpha(*s))
3935         {
3936         expand_string_message = US"missing lookup type";
3937         goto EXPAND_FAILED;
3938         }
3939
3940       /* The type is a string that may contain special characters of various
3941       kinds. Allow everything except space or { to appear; the actual content
3942       is checked by search_findtype_partial. */         /*}*/
3943
3944       while (*s != 0 && *s != '{' && !isspace(*s))      /*}*/
3945         {
3946         if (nameptr < sizeof(name) - 1) name[nameptr++] = *s;
3947         s++;
3948         }
3949       name[nameptr] = 0;
3950       while (isspace(*s)) s++;
3951
3952       /* Now check for the individual search type and any partial or default
3953       options. Only those types that are actually in the binary are valid. */
3954
3955       stype = search_findtype_partial(name, &partial, &affix, &affixlen,
3956         &starflags);
3957       if (stype < 0)
3958         {
3959         expand_string_message = search_error_message;
3960         goto EXPAND_FAILED;
3961         }
3962
3963       /* Check that a key was provided for those lookup types that need it,
3964       and was not supplied for those that use the query style. */
3965
3966       if (!mac_islookup(stype, lookup_querystyle|lookup_absfilequery))
3967         {
3968         if (key == NULL)
3969           {
3970           expand_string_message = string_sprintf("missing {key} for single-"
3971             "key \"%s\" lookup", name);
3972           goto EXPAND_FAILED;
3973           }
3974         }
3975       else
3976         {
3977         if (key != NULL)
3978           {
3979           expand_string_message = string_sprintf("a single key was given for "
3980             "lookup type \"%s\", which is not a single-key lookup type", name);
3981           goto EXPAND_FAILED;
3982           }
3983         }
3984
3985       /* Get the next string in brackets and expand it. It is the file name for
3986       single-key+file lookups, and the whole query otherwise. In the case of
3987       queries that also require a file name (e.g. sqlite), the file name comes
3988       first. */
3989
3990       if (*s != '{') goto EXPAND_FAILED_CURLY;
3991       filename = expand_string_internal(s+1, TRUE, &s, skipping, TRUE);
3992       if (filename == NULL) goto EXPAND_FAILED;
3993       if (*s++ != '}') goto EXPAND_FAILED_CURLY;
3994       while (isspace(*s)) s++;
3995
3996       /* If this isn't a single-key+file lookup, re-arrange the variables
3997       to be appropriate for the search_ functions. For query-style lookups,
3998       there is just a "key", and no file name. For the special query-style +
3999       file types, the query (i.e. "key") starts with a file name. */
4000
4001       if (key == NULL)
4002         {
4003         while (isspace(*filename)) filename++;
4004         key = filename;
4005
4006         if (mac_islookup(stype, lookup_querystyle))
4007           {
4008           filename = NULL;
4009           }
4010         else
4011           {
4012           if (*filename != '/')
4013             {
4014             expand_string_message = string_sprintf(
4015               "absolute file name expected for \"%s\" lookup", name);
4016             goto EXPAND_FAILED;
4017             }
4018           while (*key != 0 && !isspace(*key)) key++;
4019           if (*key != 0) *key++ = 0;
4020           }
4021         }
4022
4023       /* If skipping, don't do the next bit - just lookup_value == NULL, as if
4024       the entry was not found. Note that there is no search_close() function.
4025       Files are left open in case of re-use. At suitable places in higher logic,
4026       search_tidyup() is called to tidy all open files. This can save opening
4027       the same file several times. However, files may also get closed when
4028       others are opened, if too many are open at once. The rule is that a
4029       handle should not be used after a second search_open().
4030
4031       Request that a partial search sets up $1 and maybe $2 by passing
4032       expand_setup containing zero. If its value changes, reset expand_nmax,
4033       since new variables will have been set. Note that at the end of this
4034       "lookup" section, the old numeric variables are restored. */
4035
4036       if (skipping)
4037         lookup_value = NULL;
4038       else
4039         {
4040         void *handle = search_open(filename, stype, 0, NULL, NULL);
4041         if (handle == NULL)
4042           {
4043           expand_string_message = search_error_message;
4044           goto EXPAND_FAILED;
4045           }
4046         lookup_value = search_find(handle, filename, key, partial, affix,
4047           affixlen, starflags, &expand_setup);
4048         if (search_find_defer)
4049           {
4050           expand_string_message =
4051             string_sprintf("lookup of \"%s\" gave DEFER: %s",
4052               string_printing2(key, FALSE), search_error_message);
4053           goto EXPAND_FAILED;
4054           }
4055         if (expand_setup > 0) expand_nmax = expand_setup;
4056         }
4057
4058       /* The handling of "yes" and "no" result strings is now in a separate
4059       function that is also used by ${if} and ${extract}. */
4060
4061       switch(process_yesno(
4062                skipping,                     /* were previously skipping */
4063                lookup_value != NULL,         /* success/failure indicator */
4064                save_lookup_value,            /* value to reset for string2 */
4065                &s,                           /* input pointer */
4066                &yield,                       /* output pointer */
4067                &size,                        /* output size */
4068                &ptr,                         /* output current point */
4069                US"lookup"))                  /* condition type */
4070         {
4071         case 1: goto EXPAND_FAILED;          /* when all is well, the */
4072         case 2: goto EXPAND_FAILED_CURLY;    /* returned value is 0 */
4073         }
4074
4075       /* Restore external setting of expansion variables for carrying on
4076       at this level, and continue. */
4077
4078       restore_expand_strings(save_expand_nmax, save_expand_nstring,
4079         save_expand_nlength);
4080       continue;
4081       }
4082
4083     /* If Perl support is configured, handle calling embedded perl subroutines,
4084     unless locked out at this time. Syntax is ${perl{sub}} or ${perl{sub}{arg}}
4085     or ${perl{sub}{arg1}{arg2}} or up to a maximum of EXIM_PERL_MAX_ARGS
4086     arguments (defined below). */
4087
4088     #define EXIM_PERL_MAX_ARGS 8
4089
4090     case EITEM_PERL:
4091     #ifndef EXIM_PERL
4092     expand_string_message = US"\"${perl\" encountered, but this facility "      /*}*/
4093       "is not included in this binary";
4094     goto EXPAND_FAILED;
4095
4096     #else   /* EXIM_PERL */
4097       {
4098       uschar *sub_arg[EXIM_PERL_MAX_ARGS + 2];
4099       uschar *new_yield;
4100
4101       if ((expand_forbid & RDO_PERL) != 0)
4102         {
4103         expand_string_message = US"Perl calls are not permitted";
4104         goto EXPAND_FAILED;
4105         }
4106
4107       switch(read_subs(sub_arg, EXIM_PERL_MAX_ARGS + 1, 1, &s, skipping, TRUE,
4108            US"perl"))
4109         {
4110         case 1: goto EXPAND_FAILED_CURLY;
4111         case 2:
4112         case 3: goto EXPAND_FAILED;
4113         }
4114
4115       /* If skipping, we don't actually do anything */
4116
4117       if (skipping) continue;
4118
4119       /* Start the interpreter if necessary */
4120
4121       if (!opt_perl_started)
4122         {
4123         uschar *initerror;
4124         if (opt_perl_startup == NULL)
4125           {
4126           expand_string_message = US"A setting of perl_startup is needed when "
4127             "using the Perl interpreter";
4128           goto EXPAND_FAILED;
4129           }
4130         DEBUG(D_any) debug_printf("Starting Perl interpreter\n");
4131         initerror = init_perl(opt_perl_startup);
4132         if (initerror != NULL)
4133           {
4134           expand_string_message =
4135             string_sprintf("error in perl_startup code: %s\n", initerror);
4136           goto EXPAND_FAILED;
4137           }
4138         opt_perl_started = TRUE;
4139         }
4140
4141       /* Call the function */
4142
4143       sub_arg[EXIM_PERL_MAX_ARGS + 1] = NULL;
4144       new_yield = call_perl_cat(yield, &size, &ptr, &expand_string_message,
4145         sub_arg[0], sub_arg + 1);
4146
4147       /* NULL yield indicates failure; if the message pointer has been set to
4148       NULL, the yield was undef, indicating a forced failure. Otherwise the
4149       message will indicate some kind of Perl error. */
4150
4151       if (new_yield == NULL)
4152         {
4153         if (expand_string_message == NULL)
4154           {
4155           expand_string_message =
4156             string_sprintf("Perl subroutine \"%s\" returned undef to force "
4157               "failure", sub_arg[0]);
4158           expand_string_forcedfail = TRUE;
4159           }
4160         goto EXPAND_FAILED;
4161         }
4162
4163       /* Yield succeeded. Ensure forcedfail is unset, just in case it got
4164       set during a callback from Perl. */
4165
4166       expand_string_forcedfail = FALSE;
4167       yield = new_yield;
4168       continue;
4169       }
4170     #endif /* EXIM_PERL */
4171
4172     /* Transform email address to "prvs" scheme to use
4173        as BATV-signed return path */
4174
4175     case EITEM_PRVS:
4176       {
4177       uschar *sub_arg[3];
4178       uschar *p,*domain;
4179
4180       switch(read_subs(sub_arg, 3, 2, &s, skipping, TRUE, US"prvs"))
4181         {
4182         case 1: goto EXPAND_FAILED_CURLY;
4183         case 2:
4184         case 3: goto EXPAND_FAILED;
4185         }
4186
4187       /* If skipping, we don't actually do anything */
4188       if (skipping) continue;
4189
4190       /* sub_arg[0] is the address */
4191       domain = Ustrrchr(sub_arg[0],'@');
4192       if ( (domain == NULL) || (domain == sub_arg[0]) || (Ustrlen(domain) == 1) )
4193         {
4194         expand_string_message = US"prvs first argument must be a qualified email address";
4195         goto EXPAND_FAILED;
4196         }
4197
4198       /* Calculate the hash. The second argument must be a single-digit
4199       key number, or unset. */
4200
4201       if (sub_arg[2] != NULL &&
4202           (!isdigit(sub_arg[2][0]) || sub_arg[2][1] != 0))
4203         {
4204         expand_string_message = US"prvs second argument must be a single digit";
4205         goto EXPAND_FAILED;
4206         }
4207
4208       p = prvs_hmac_sha1(sub_arg[0],sub_arg[1],sub_arg[2],prvs_daystamp(7));
4209       if (p == NULL)
4210         {
4211         expand_string_message = US"prvs hmac-sha1 conversion failed";
4212         goto EXPAND_FAILED;
4213         }
4214
4215       /* Now separate the domain from the local part */
4216       *domain++ = '\0';
4217
4218       yield = string_cat(yield,&size,&ptr,US"prvs=",5);
4219       string_cat(yield,&size,&ptr,(sub_arg[2] != NULL) ? sub_arg[2] : US"0", 1);
4220       string_cat(yield,&size,&ptr,prvs_daystamp(7),3);
4221       string_cat(yield,&size,&ptr,p,6);
4222       string_cat(yield,&size,&ptr,US"=",1);
4223       string_cat(yield,&size,&ptr,sub_arg[0],Ustrlen(sub_arg[0]));
4224       string_cat(yield,&size,&ptr,US"@",1);
4225       string_cat(yield,&size,&ptr,domain,Ustrlen(domain));
4226
4227       continue;
4228       }
4229
4230     /* Check a prvs-encoded address for validity */
4231
4232     case EITEM_PRVSCHECK:
4233       {
4234       uschar *sub_arg[3];
4235       int mysize = 0, myptr = 0;
4236       const pcre *re;
4237       uschar *p;
4238
4239       /* TF: Ugliness: We want to expand parameter 1 first, then set
4240          up expansion variables that are used in the expansion of
4241          parameter 2. So we clone the string for the first
4242          expansion, where we only expand parameter 1.
4243
4244          PH: Actually, that isn't necessary. The read_subs() function is
4245          designed to work this way for the ${if and ${lookup expansions. I've
4246          tidied the code.
4247       */
4248
4249       /* Reset expansion variables */
4250       prvscheck_result = NULL;
4251       prvscheck_address = NULL;
4252       prvscheck_keynum = NULL;
4253
4254       switch(read_subs(sub_arg, 1, 1, &s, skipping, FALSE, US"prvs"))
4255         {
4256         case 1: goto EXPAND_FAILED_CURLY;
4257         case 2:
4258         case 3: goto EXPAND_FAILED;
4259         }
4260
4261       re = regex_must_compile(US"^prvs\\=([0-9])([0-9]{3})([A-F0-9]{6})\\=(.+)\\@(.+)$",
4262                               TRUE,FALSE);
4263
4264       if (regex_match_and_setup(re,sub_arg[0],0,-1))
4265         {
4266         uschar *local_part = string_copyn(expand_nstring[4],expand_nlength[4]);
4267         uschar *key_num = string_copyn(expand_nstring[1],expand_nlength[1]);
4268         uschar *daystamp = string_copyn(expand_nstring[2],expand_nlength[2]);
4269         uschar *hash = string_copyn(expand_nstring[3],expand_nlength[3]);
4270         uschar *domain = string_copyn(expand_nstring[5],expand_nlength[5]);
4271
4272         DEBUG(D_expand) debug_printf("prvscheck localpart: %s\n", local_part);
4273         DEBUG(D_expand) debug_printf("prvscheck key number: %s\n", key_num);
4274         DEBUG(D_expand) debug_printf("prvscheck daystamp: %s\n", daystamp);
4275         DEBUG(D_expand) debug_printf("prvscheck hash: %s\n", hash);
4276         DEBUG(D_expand) debug_printf("prvscheck domain: %s\n", domain);
4277
4278         /* Set up expansion variables */
4279         prvscheck_address = string_cat(NULL, &mysize, &myptr, local_part, Ustrlen(local_part));
4280         string_cat(prvscheck_address,&mysize,&myptr,US"@",1);
4281         string_cat(prvscheck_address,&mysize,&myptr,domain,Ustrlen(domain));
4282         prvscheck_address[myptr] = '\0';
4283         prvscheck_keynum = string_copy(key_num);
4284
4285         /* Now expand the second argument */
4286         switch(read_subs(sub_arg, 1, 1, &s, skipping, FALSE, US"prvs"))
4287           {
4288           case 1: goto EXPAND_FAILED_CURLY;
4289           case 2:
4290           case 3: goto EXPAND_FAILED;
4291           }
4292
4293         /* Now we have the key and can check the address. */
4294
4295         p = prvs_hmac_sha1(prvscheck_address, sub_arg[0], prvscheck_keynum,
4296           daystamp);
4297
4298         if (p == NULL)
4299           {
4300           expand_string_message = US"hmac-sha1 conversion failed";
4301           goto EXPAND_FAILED;
4302           }
4303
4304         DEBUG(D_expand) debug_printf("prvscheck: received hash is %s\n", hash);
4305         DEBUG(D_expand) debug_printf("prvscheck:      own hash is %s\n", p);
4306
4307         if (Ustrcmp(p,hash) == 0)
4308           {
4309           /* Success, valid BATV address. Now check the expiry date. */
4310           uschar *now = prvs_daystamp(0);
4311           unsigned int inow = 0,iexpire = 1;
4312
4313           (void)sscanf(CS now,"%u",&inow);
4314           (void)sscanf(CS daystamp,"%u",&iexpire);
4315
4316           /* When "iexpire" is < 7, a "flip" has occured.
4317              Adjust "inow" accordingly. */
4318           if ( (iexpire < 7) && (inow >= 993) ) inow = 0;
4319
4320           if (iexpire >= inow)
4321             {
4322             prvscheck_result = US"1";
4323             DEBUG(D_expand) debug_printf("prvscheck: success, $pvrs_result set to 1\n");
4324             }
4325             else
4326             {
4327             prvscheck_result = NULL;
4328             DEBUG(D_expand) debug_printf("prvscheck: signature expired, $pvrs_result unset\n");
4329             }
4330           }
4331         else
4332           {
4333           prvscheck_result = NULL;
4334           DEBUG(D_expand) debug_printf("prvscheck: hash failure, $pvrs_result unset\n");
4335           }
4336
4337         /* Now expand the final argument. We leave this till now so that
4338         it can include $prvscheck_result. */
4339
4340         switch(read_subs(sub_arg, 1, 0, &s, skipping, TRUE, US"prvs"))
4341           {
4342           case 1: goto EXPAND_FAILED_CURLY;
4343           case 2:
4344           case 3: goto EXPAND_FAILED;
4345           }
4346
4347         if (sub_arg[0] == NULL || *sub_arg[0] == '\0')
4348           yield = string_cat(yield,&size,&ptr,prvscheck_address,Ustrlen(prvscheck_address));
4349         else
4350           yield = string_cat(yield,&size,&ptr,sub_arg[0],Ustrlen(sub_arg[0]));
4351
4352         /* Reset the "internal" variables afterwards, because they are in
4353         dynamic store that will be reclaimed if the expansion succeeded. */
4354
4355         prvscheck_address = NULL;
4356         prvscheck_keynum = NULL;
4357         }
4358       else
4359         {
4360         /* Does not look like a prvs encoded address, return the empty string.
4361            We need to make sure all subs are expanded first, so as to skip over
4362            the entire item. */
4363
4364         switch(read_subs(sub_arg, 2, 1, &s, skipping, TRUE, US"prvs"))
4365           {
4366           case 1: goto EXPAND_FAILED_CURLY;
4367           case 2:
4368           case 3: goto EXPAND_FAILED;
4369           }
4370         }
4371
4372       continue;
4373       }
4374
4375     /* Handle "readfile" to insert an entire file */
4376
4377     case EITEM_READFILE:
4378       {
4379       FILE *f;
4380       uschar *sub_arg[2];
4381
4382       if ((expand_forbid & RDO_READFILE) != 0)
4383         {
4384         expand_string_message = US"file insertions are not permitted";
4385         goto EXPAND_FAILED;
4386         }
4387
4388       switch(read_subs(sub_arg, 2, 1, &s, skipping, TRUE, US"readfile"))
4389         {
4390         case 1: goto EXPAND_FAILED_CURLY;
4391         case 2:
4392         case 3: goto EXPAND_FAILED;
4393         }
4394
4395       /* If skipping, we don't actually do anything */
4396
4397       if (skipping) continue;
4398
4399       /* Open the file and read it */
4400
4401       f = Ufopen(sub_arg[0], "rb");
4402       if (f == NULL)
4403         {
4404         expand_string_message = string_open_failed(errno, "%s", sub_arg[0]);
4405         goto EXPAND_FAILED;
4406         }
4407
4408       yield = cat_file(f, yield, &size, &ptr, sub_arg[1]);
4409       (void)fclose(f);
4410       continue;
4411       }
4412
4413     /* Handle "readsocket" to insert data from a Unix domain socket */
4414
4415     case EITEM_READSOCK:
4416       {
4417       int fd;
4418       int timeout = 5;
4419       int save_ptr = ptr;
4420       FILE *f;
4421       struct sockaddr_un sockun;         /* don't call this "sun" ! */
4422       uschar *arg;
4423       uschar *sub_arg[4];
4424
4425       if ((expand_forbid & RDO_READSOCK) != 0)
4426         {
4427         expand_string_message = US"socket insertions are not permitted";
4428         goto EXPAND_FAILED;
4429         }
4430
4431       /* Read up to 4 arguments, but don't do the end of item check afterwards,
4432       because there may be a string for expansion on failure. */
4433
4434       switch(read_subs(sub_arg, 4, 2, &s, skipping, FALSE, US"readsocket"))
4435         {
4436         case 1: goto EXPAND_FAILED_CURLY;
4437         case 2:                             /* Won't occur: no end check */
4438         case 3: goto EXPAND_FAILED;
4439         }
4440
4441       /* Sort out timeout, if given */
4442
4443       if (sub_arg[2] != NULL)
4444         {
4445         timeout = readconf_readtime(sub_arg[2], 0, FALSE);
4446         if (timeout < 0)
4447           {
4448           expand_string_message = string_sprintf("bad time value %s",
4449             sub_arg[2]);
4450           goto EXPAND_FAILED;
4451           }
4452         }
4453       else sub_arg[3] = NULL;                     /* No eol if no timeout */
4454
4455       /* If skipping, we don't actually do anything. Otherwise, arrange to
4456       connect to either an IP or a Unix socket. */
4457
4458       if (!skipping)
4459         {
4460         /* Handle an IP (internet) domain */
4461
4462         if (Ustrncmp(sub_arg[0], "inet:", 5) == 0)
4463           {
4464           BOOL connected = FALSE;
4465           int namelen, port;
4466           host_item shost;
4467           host_item *h;
4468           uschar *server_name = sub_arg[0] + 5;
4469           uschar *port_name = Ustrrchr(server_name, ':');
4470
4471           /* Sort out the port */
4472
4473           if (port_name == NULL)
4474             {
4475             expand_string_message =
4476               string_sprintf("missing port for readsocket %s", sub_arg[0]);
4477             goto EXPAND_FAILED;
4478             }
4479           *port_name++ = 0;           /* Terminate server name */
4480
4481           if (isdigit(*port_name))
4482             {
4483             uschar *end;
4484             port = Ustrtol(port_name, &end, 0);
4485             if (end != port_name + Ustrlen(port_name))
4486               {
4487               expand_string_message =
4488                 string_sprintf("invalid port number %s", port_name);
4489               goto EXPAND_FAILED;
4490               }
4491             }
4492           else
4493             {
4494             struct servent *service_info = getservbyname(CS port_name, "tcp");
4495             if (service_info == NULL)
4496               {
4497               expand_string_message = string_sprintf("unknown port \"%s\"",
4498                 port_name);
4499               goto EXPAND_FAILED;
4500               }
4501             port = ntohs(service_info->s_port);
4502             }
4503
4504           /* Sort out the server. */
4505
4506           shost.next = NULL;
4507           shost.address = NULL;
4508           shost.port = port;
4509           shost.mx = -1;
4510
4511           namelen = Ustrlen(server_name);
4512
4513           /* Anything enclosed in [] must be an IP address. */
4514
4515           if (server_name[0] == '[' &&
4516               server_name[namelen - 1] == ']')
4517             {
4518             server_name[namelen - 1] = 0;
4519             server_name++;
4520             if (string_is_ip_address(server_name, NULL) == 0)
4521               {
4522               expand_string_message =
4523                 string_sprintf("malformed IP address \"%s\"", server_name);
4524               goto EXPAND_FAILED;
4525               }
4526             shost.name = shost.address = server_name;
4527             }
4528
4529           /* Otherwise check for an unadorned IP address */
4530
4531           else if (string_is_ip_address(server_name, NULL) != 0)
4532             shost.name = shost.address = server_name;
4533
4534           /* Otherwise lookup IP address(es) from the name */
4535
4536           else
4537             {
4538             shost.name = server_name;
4539             if (host_find_byname(&shost, NULL, HOST_FIND_QUALIFY_SINGLE, NULL,
4540                 FALSE) != HOST_FOUND)
4541               {
4542               expand_string_message =
4543                 string_sprintf("no IP address found for host %s", shost.name);
4544               goto EXPAND_FAILED;
4545               }
4546             }
4547
4548           /* Try to connect to the server - test each IP till one works */
4549
4550           for (h = &shost; h != NULL; h = h->next)
4551             {
4552             int af = (Ustrchr(h->address, ':') != 0)? AF_INET6 : AF_INET;
4553             if ((fd = ip_socket(SOCK_STREAM, af)) == -1)
4554               {
4555               expand_string_message = string_sprintf("failed to create socket: "
4556                 "%s", strerror(errno));
4557               goto SOCK_FAIL;
4558               }
4559
4560             if (ip_connect(fd, af, h->address, port, timeout) == 0)
4561               {
4562               connected = TRUE;
4563               break;
4564               }
4565             }
4566
4567           if (!connected)
4568             {
4569             expand_string_message = string_sprintf("failed to connect to "
4570               "socket %s: couldn't connect to any host", sub_arg[0],
4571               strerror(errno));
4572             goto SOCK_FAIL;
4573             }
4574           }
4575
4576         /* Handle a Unix domain socket */
4577
4578         else
4579           {
4580           int rc;
4581           if ((fd = socket(PF_UNIX, SOCK_STREAM, 0)) == -1)
4582             {
4583             expand_string_message = string_sprintf("failed to create socket: %s",
4584               strerror(errno));
4585             goto SOCK_FAIL;
4586             }
4587
4588           sockun.sun_family = AF_UNIX;
4589           sprintf(sockun.sun_path, "%.*s", (int)(sizeof(sockun.sun_path)-1),
4590             sub_arg[0]);
4591
4592           sigalrm_seen = FALSE;
4593           alarm(timeout);
4594           rc = connect(fd, (struct sockaddr *)(&sockun), sizeof(sockun));
4595           alarm(0);
4596           if (sigalrm_seen)
4597             {
4598             expand_string_message = US "socket connect timed out";
4599             goto SOCK_FAIL;
4600             }
4601           if (rc < 0)
4602             {
4603             expand_string_message = string_sprintf("failed to connect to socket "
4604               "%s: %s", sub_arg[0], strerror(errno));
4605             goto SOCK_FAIL;
4606             }
4607           }
4608
4609         DEBUG(D_expand) debug_printf("connected to socket %s\n", sub_arg[0]);
4610
4611         /* Write the request string, if not empty */
4612
4613         if (sub_arg[1][0] != 0)
4614           {
4615           int len = Ustrlen(sub_arg[1]);
4616           DEBUG(D_expand) debug_printf("writing \"%s\" to socket\n",
4617             sub_arg[1]);
4618           if (write(fd, sub_arg[1], len) != len)
4619             {
4620             expand_string_message = string_sprintf("request write to socket "
4621               "failed: %s", strerror(errno));
4622             goto SOCK_FAIL;
4623             }
4624           }
4625
4626         /* Shut down the sending side of the socket. This helps some servers to
4627         recognise that it is their turn to do some work. Just in case some
4628         system doesn't have this function, make it conditional. */
4629
4630         #ifdef SHUT_WR
4631         shutdown(fd, SHUT_WR);
4632         #endif
4633
4634         /* Now we need to read from the socket, under a timeout. The function
4635         that reads a file can be used. */
4636
4637         f = fdopen(fd, "rb");
4638         sigalrm_seen = FALSE;
4639         alarm(timeout);
4640         yield = cat_file(f, yield, &size, &ptr, sub_arg[3]);
4641         alarm(0);
4642         (void)fclose(f);
4643
4644         /* After a timeout, we restore the pointer in the result, that is,
4645         make sure we add nothing from the socket. */
4646
4647         if (sigalrm_seen)
4648           {
4649           ptr = save_ptr;
4650           expand_string_message = US "socket read timed out";
4651           goto SOCK_FAIL;
4652           }
4653         }
4654
4655       /* The whole thing has worked (or we were skipping). If there is a
4656       failure string following, we need to skip it. */
4657
4658       if (*s == '{')
4659         {
4660         if (expand_string_internal(s+1, TRUE, &s, TRUE, TRUE) == NULL)
4661           goto EXPAND_FAILED;
4662         if (*s++ != '}') goto EXPAND_FAILED_CURLY;
4663         while (isspace(*s)) s++;
4664         }
4665       if (*s++ != '}') goto EXPAND_FAILED_CURLY;
4666       continue;
4667
4668       /* Come here on failure to create socket, connect socket, write to the
4669       socket, or timeout on reading. If another substring follows, expand and
4670       use it. Otherwise, those conditions give expand errors. */
4671
4672       SOCK_FAIL:
4673       if (*s != '{') goto EXPAND_FAILED;
4674       DEBUG(D_any) debug_printf("%s\n", expand_string_message);
4675       arg = expand_string_internal(s+1, TRUE, &s, FALSE, TRUE);
4676       if (arg == NULL) goto EXPAND_FAILED;
4677       yield = string_cat(yield, &size, &ptr, arg, Ustrlen(arg));
4678       if (*s++ != '}') goto EXPAND_FAILED_CURLY;
4679       while (isspace(*s)) s++;
4680       if (*s++ != '}') goto EXPAND_FAILED_CURLY;
4681       continue;
4682       }
4683
4684     /* Handle "run" to execute a program. */
4685
4686     case EITEM_RUN:
4687       {
4688       FILE *f;
4689       uschar *arg;
4690       uschar **argv;
4691       pid_t pid;
4692       int fd_in, fd_out;
4693       int lsize = 0;
4694       int lptr = 0;
4695
4696       if ((expand_forbid & RDO_RUN) != 0)
4697         {
4698         expand_string_message = US"running a command is not permitted";
4699         goto EXPAND_FAILED;
4700         }
4701
4702       while (isspace(*s)) s++;
4703       if (*s != '{') goto EXPAND_FAILED_CURLY;
4704       arg = expand_string_internal(s+1, TRUE, &s, skipping, TRUE);
4705       if (arg == NULL) goto EXPAND_FAILED;
4706       while (isspace(*s)) s++;
4707       if (*s++ != '}') goto EXPAND_FAILED_CURLY;
4708
4709       if (skipping)   /* Just pretend it worked when we're skipping */
4710         {
4711         runrc = 0;
4712         }
4713       else
4714         {
4715         if (!transport_set_up_command(&argv,    /* anchor for arg list */
4716             arg,                                /* raw command */
4717             FALSE,                              /* don't expand the arguments */
4718             0,                                  /* not relevant when... */
4719             NULL,                               /* no transporting address */
4720             US"${run} expansion",               /* for error messages */
4721             &expand_string_message))            /* where to put error message */
4722           {
4723           goto EXPAND_FAILED;
4724           }
4725
4726         /* Create the child process, making it a group leader. */
4727
4728         pid = child_open(argv, NULL, 0077, &fd_in, &fd_out, TRUE);
4729
4730         if (pid < 0)
4731           {
4732           expand_string_message =
4733             string_sprintf("couldn't create child process: %s", strerror(errno));
4734           goto EXPAND_FAILED;
4735           }
4736
4737         /* Nothing is written to the standard input. */
4738
4739         (void)close(fd_in);
4740
4741         /* Read the pipe to get the command's output into $value (which is kept
4742         in lookup_value). Read during execution, so that if the output exceeds
4743         the OS pipe buffer limit, we don't block forever. */
4744
4745         f = fdopen(fd_out, "rb");
4746         sigalrm_seen = FALSE;
4747         alarm(60);
4748         lookup_value = cat_file(f, lookup_value, &lsize, &lptr, NULL);
4749         alarm(0);
4750         (void)fclose(f);
4751
4752         /* Wait for the process to finish, applying the timeout, and inspect its
4753         return code for serious disasters. Simple non-zero returns are passed on.
4754         */
4755
4756         if (sigalrm_seen == TRUE || (runrc = child_close(pid, 30)) < 0)
4757           {
4758           if (sigalrm_seen == TRUE || runrc == -256)
4759             {
4760             expand_string_message = string_sprintf("command timed out");
4761             killpg(pid, SIGKILL);       /* Kill the whole process group */
4762             }
4763
4764           else if (runrc == -257)
4765             expand_string_message = string_sprintf("wait() failed: %s",
4766               strerror(errno));
4767
4768           else
4769             expand_string_message = string_sprintf("command killed by signal %d",
4770               -runrc);
4771
4772           goto EXPAND_FAILED;
4773           }
4774         }
4775
4776       /* Process the yes/no strings; $value may be useful in both cases */
4777
4778       switch(process_yesno(
4779                skipping,                     /* were previously skipping */
4780                runrc == 0,                   /* success/failure indicator */
4781                lookup_value,                 /* value to reset for string2 */
4782                &s,                           /* input pointer */
4783                &yield,                       /* output pointer */
4784                &size,                        /* output size */
4785                &ptr,                         /* output current point */
4786                US"run"))                     /* condition type */
4787         {
4788         case 1: goto EXPAND_FAILED;          /* when all is well, the */
4789         case 2: goto EXPAND_FAILED_CURLY;    /* returned value is 0 */
4790         }
4791
4792       continue;
4793       }
4794
4795     /* Handle character translation for "tr" */
4796
4797     case EITEM_TR:
4798       {
4799       int oldptr = ptr;
4800       int o2m;
4801       uschar *sub[3];
4802
4803       switch(read_subs(sub, 3, 3, &s, skipping, TRUE, US"tr"))
4804         {
4805         case 1: goto EXPAND_FAILED_CURLY;
4806         case 2:
4807         case 3: goto EXPAND_FAILED;
4808         }
4809
4810       yield = string_cat(yield, &size, &ptr, sub[0], Ustrlen(sub[0]));
4811       o2m = Ustrlen(sub[2]) - 1;
4812
4813       if (o2m >= 0) for (; oldptr < ptr; oldptr++)
4814         {
4815         uschar *m = Ustrrchr(sub[1], yield[oldptr]);
4816         if (m != NULL)
4817           {
4818           int o = m - sub[1];
4819           yield[oldptr] = sub[2][(o < o2m)? o : o2m];
4820           }
4821         }
4822
4823       continue;
4824       }
4825
4826     /* Handle "hash", "length", "nhash", and "substr" when they are given with
4827     expanded arguments. */
4828
4829     case EITEM_HASH:
4830     case EITEM_LENGTH:
4831     case EITEM_NHASH:
4832     case EITEM_SUBSTR:
4833       {
4834       int i;
4835       int len;
4836       uschar *ret;
4837       int val[2] = { 0, -1 };
4838       uschar *sub[3];
4839
4840       /* "length" takes only 2 arguments whereas the others take 2 or 3.
4841       Ensure that sub[2] is set in the ${length } case. */
4842
4843       sub[2] = NULL;
4844       switch(read_subs(sub, (item_type == EITEM_LENGTH)? 2:3, 2, &s, skipping,
4845              TRUE, name))
4846         {
4847         case 1: goto EXPAND_FAILED_CURLY;
4848         case 2:
4849         case 3: goto EXPAND_FAILED;
4850         }
4851
4852       /* Juggle the arguments if there are only two of them: always move the
4853       string to the last position and make ${length{n}{str}} equivalent to
4854       ${substr{0}{n}{str}}. See the defaults for val[] above. */
4855
4856       if (sub[2] == NULL)
4857         {
4858         sub[2] = sub[1];
4859         sub[1] = NULL;
4860         if (item_type == EITEM_LENGTH)
4861           {
4862           sub[1] = sub[0];
4863           sub[0] = NULL;
4864           }
4865         }
4866
4867       for (i = 0; i < 2; i++)
4868         {
4869         if (sub[i] == NULL) continue;
4870         val[i] = (int)Ustrtol(sub[i], &ret, 10);
4871         if (*ret != 0 || (i != 0 && val[i] < 0))
4872           {
4873           expand_string_message = string_sprintf("\"%s\" is not a%s number "
4874             "(in \"%s\" expansion)", sub[i], (i != 0)? " positive" : "", name);
4875           goto EXPAND_FAILED;
4876           }
4877         }
4878
4879       ret =
4880         (item_type == EITEM_HASH)?
4881           compute_hash(sub[2], val[0], val[1], &len) :
4882         (item_type == EITEM_NHASH)?
4883           compute_nhash(sub[2], val[0], val[1], &len) :
4884           extract_substr(sub[2], val[0], val[1], &len);
4885
4886       if (ret == NULL) goto EXPAND_FAILED;
4887       yield = string_cat(yield, &size, &ptr, ret, len);
4888       continue;
4889       }
4890
4891     /* Handle HMAC computation: ${hmac{<algorithm>}{<secret>}{<text>}}
4892     This code originally contributed by Steve Haslam. It currently supports
4893     the use of MD5 and SHA-1 hashes.
4894
4895     We need some workspace that is large enough to handle all the supported
4896     hash types. Use macros to set the sizes rather than be too elaborate. */
4897
4898     #define MAX_HASHLEN      20
4899     #define MAX_HASHBLOCKLEN 64
4900
4901     case EITEM_HMAC:
4902       {
4903       uschar *sub[3];
4904       md5 md5_base;
4905       sha1 sha1_base;
4906       void *use_base;
4907       int type, i;
4908       int hashlen;      /* Number of octets for the hash algorithm's output */
4909       int hashblocklen; /* Number of octets the hash algorithm processes */
4910       uschar *keyptr, *p;
4911       unsigned int keylen;
4912
4913       uschar keyhash[MAX_HASHLEN];
4914       uschar innerhash[MAX_HASHLEN];
4915       uschar finalhash[MAX_HASHLEN];
4916       uschar finalhash_hex[2*MAX_HASHLEN];
4917       uschar innerkey[MAX_HASHBLOCKLEN];
4918       uschar outerkey[MAX_HASHBLOCKLEN];
4919
4920       switch (read_subs(sub, 3, 3, &s, skipping, TRUE, name))
4921         {
4922         case 1: goto EXPAND_FAILED_CURLY;
4923         case 2:
4924         case 3: goto EXPAND_FAILED;
4925         }
4926
4927       if (Ustrcmp(sub[0], "md5") == 0)
4928         {
4929         type = HMAC_MD5;
4930         use_base = &md5_base;
4931         hashlen = 16;
4932         hashblocklen = 64;
4933         }
4934       else if (Ustrcmp(sub[0], "sha1") == 0)
4935         {
4936         type = HMAC_SHA1;
4937         use_base = &sha1_base;
4938         hashlen = 20;
4939         hashblocklen = 64;
4940         }
4941       else
4942         {
4943         expand_string_message =
4944           string_sprintf("hmac algorithm \"%s\" is not recognised", sub[0]);
4945         goto EXPAND_FAILED;
4946         }
4947
4948       keyptr = sub[1];
4949       keylen = Ustrlen(keyptr);
4950
4951       /* If the key is longer than the hash block length, then hash the key
4952       first */
4953
4954       if (keylen > hashblocklen)
4955         {
4956         chash_start(type, use_base);
4957         chash_end(type, use_base, keyptr, keylen, keyhash);
4958         keyptr = keyhash;
4959         keylen = hashlen;
4960         }
4961
4962       /* Now make the inner and outer key values */
4963
4964       memset(innerkey, 0x36, hashblocklen);
4965       memset(outerkey, 0x5c, hashblocklen);
4966
4967       for (i = 0; i < keylen; i++)
4968         {
4969         innerkey[i] ^= keyptr[i];
4970         outerkey[i] ^= keyptr[i];
4971         }
4972
4973       /* Now do the hashes */
4974
4975       chash_start(type, use_base);
4976       chash_mid(type, use_base, innerkey);
4977       chash_end(type, use_base, sub[2], Ustrlen(sub[2]), innerhash);
4978
4979       chash_start(type, use_base);
4980       chash_mid(type, use_base, outerkey);
4981       chash_end(type, use_base, innerhash, hashlen, finalhash);
4982
4983       /* Encode the final hash as a hex string */
4984
4985       p = finalhash_hex;
4986       for (i = 0; i < hashlen; i++)
4987         {
4988         *p++ = hex_digits[(finalhash[i] & 0xf0) >> 4];
4989         *p++ = hex_digits[finalhash[i] & 0x0f];
4990         }
4991
4992       DEBUG(D_any) debug_printf("HMAC[%s](%.*s,%.*s)=%.*s\n", sub[0],
4993         (int)keylen, keyptr, Ustrlen(sub[2]), sub[2], hashlen*2, finalhash_hex);
4994
4995       yield = string_cat(yield, &size, &ptr, finalhash_hex, hashlen*2);
4996       }
4997
4998     continue;
4999
5000     /* Handle global substitution for "sg" - like Perl's s/xxx/yyy/g operator.
5001     We have to save the numerical variables and restore them afterwards. */
5002
5003     case EITEM_SG:
5004       {
5005       const pcre *re;
5006       int moffset, moffsetextra, slen;
5007       int roffset;
5008       int emptyopt;
5009       const uschar *rerror;
5010       uschar *subject;
5011       uschar *sub[3];
5012       int save_expand_nmax =
5013         save_expand_strings(save_expand_nstring, save_expand_nlength);
5014
5015       switch(read_subs(sub, 3, 3, &s, skipping, TRUE, US"sg"))
5016         {
5017         case 1: goto EXPAND_FAILED_CURLY;
5018         case 2:
5019         case 3: goto EXPAND_FAILED;
5020         }
5021
5022       /* Compile the regular expression */
5023
5024       re = pcre_compile(CS sub[1], PCRE_COPT, (const char **)&rerror, &roffset,
5025         NULL);
5026
5027       if (re == NULL)
5028         {
5029         expand_string_message = string_sprintf("regular expression error in "
5030           "\"%s\": %s at offset %d", sub[1], rerror, roffset);
5031         goto EXPAND_FAILED;
5032         }
5033
5034       /* Now run a loop to do the substitutions as often as necessary. It ends
5035       when there are no more matches. Take care over matches of the null string;
5036       do the same thing as Perl does. */
5037
5038       subject = sub[0];
5039       slen = Ustrlen(sub[0]);
5040       moffset = moffsetextra = 0;
5041       emptyopt = 0;
5042
5043       for (;;)
5044         {
5045         int ovector[3*(EXPAND_MAXN+1)];
5046         int n = pcre_exec(re, NULL, CS subject, slen, moffset + moffsetextra,
5047           PCRE_EOPT | emptyopt, ovector, sizeof(ovector)/sizeof(int));
5048         int nn;
5049         uschar *insert;
5050
5051         /* No match - if we previously set PCRE_NOTEMPTY after a null match, this
5052         is not necessarily the end. We want to repeat the match from one
5053         character further along, but leaving the basic offset the same (for
5054         copying below). We can't be at the end of the string - that was checked
5055         before setting PCRE_NOTEMPTY. If PCRE_NOTEMPTY is not set, we are
5056         finished; copy the remaining string and end the loop. */
5057
5058         if (n < 0)
5059           {
5060           if (emptyopt != 0)
5061             {
5062             moffsetextra = 1;
5063             emptyopt = 0;
5064             continue;
5065             }
5066           yield = string_cat(yield, &size, &ptr, subject+moffset, slen-moffset);
5067           break;
5068           }
5069
5070         /* Match - set up for expanding the replacement. */
5071
5072         if (n == 0) n = EXPAND_MAXN + 1;
5073         expand_nmax = 0;
5074         for (nn = 0; nn < n*2; nn += 2)
5075           {
5076           expand_nstring[expand_nmax] = subject + ovector[nn];
5077           expand_nlength[expand_nmax++] = ovector[nn+1] - ovector[nn];
5078           }
5079         expand_nmax--;
5080
5081         /* Copy the characters before the match, plus the expanded insertion. */
5082
5083         yield = string_cat(yield, &size, &ptr, subject + moffset,
5084           ovector[0] - moffset);
5085         insert = expand_string(sub[2]);
5086         if (insert == NULL) goto EXPAND_FAILED;
5087         yield = string_cat(yield, &size, &ptr, insert, Ustrlen(insert));
5088
5089         moffset = ovector[1];
5090         moffsetextra = 0;
5091         emptyopt = 0;
5092
5093         /* If we have matched an empty string, first check to see if we are at
5094         the end of the subject. If so, the loop is over. Otherwise, mimic
5095         what Perl's /g options does. This turns out to be rather cunning. First
5096         we set PCRE_NOTEMPTY and PCRE_ANCHORED and try the match a non-empty
5097         string at the same point. If this fails (picked up above) we advance to
5098         the next character. */
5099
5100         if (ovector[0] == ovector[1])
5101           {
5102           if (ovector[0] == slen) break;
5103           emptyopt = PCRE_NOTEMPTY | PCRE_ANCHORED;
5104           }
5105         }
5106
5107       /* All done - restore numerical variables. */
5108
5109       restore_expand_strings(save_expand_nmax, save_expand_nstring,
5110         save_expand_nlength);
5111       continue;
5112       }
5113
5114     /* Handle keyed and numbered substring extraction. If the first argument
5115     consists entirely of digits, then a numerical extraction is assumed. */
5116
5117     case EITEM_EXTRACT:
5118       {
5119       int i;
5120       int j = 2;
5121       int field_number = 1;
5122       BOOL field_number_set = FALSE;
5123       uschar *save_lookup_value = lookup_value;
5124       uschar *sub[3];
5125       int save_expand_nmax =
5126         save_expand_strings(save_expand_nstring, save_expand_nlength);
5127
5128       /* Read the arguments */
5129
5130       for (i = 0; i < j; i++)
5131         {
5132         while (isspace(*s)) s++;
5133         if (*s == '{')
5134           {
5135           sub[i] = expand_string_internal(s+1, TRUE, &s, skipping, TRUE);
5136           if (sub[i] == NULL) goto EXPAND_FAILED;
5137           if (*s++ != '}') goto EXPAND_FAILED_CURLY;
5138
5139           /* After removal of leading and trailing white space, the first
5140           argument must not be empty; if it consists entirely of digits
5141           (optionally preceded by a minus sign), this is a numerical
5142           extraction, and we expect 3 arguments. */
5143
5144           if (i == 0)
5145             {
5146             int len;
5147             int x = 0;
5148             uschar *p = sub[0];
5149
5150             while (isspace(*p)) p++;
5151             sub[0] = p;
5152
5153             len = Ustrlen(p);
5154             while (len > 0 && isspace(p[len-1])) len--;
5155             p[len] = 0;
5156
5157             if (*p == 0 && !skipping)
5158               {
5159               expand_string_message = US"first argument of \"extract\" must "
5160                 "not be empty";
5161               goto EXPAND_FAILED;
5162               }
5163
5164             if (*p == '-')
5165               {
5166               field_number = -1;
5167               p++;
5168               }
5169             while (*p != 0 && isdigit(*p)) x = x * 10 + *p++ - '0';
5170             if (*p == 0)
5171               {
5172               field_number *= x;
5173               j = 3;               /* Need 3 args */
5174               field_number_set = TRUE;
5175               }
5176             }
5177           }
5178         else goto EXPAND_FAILED_CURLY;
5179         }
5180
5181       /* Extract either the numbered or the keyed substring into $value. If
5182       skipping, just pretend the extraction failed. */
5183
5184       lookup_value = skipping? NULL : field_number_set?
5185         expand_gettokened(field_number, sub[1], sub[2]) :
5186         expand_getkeyed(sub[0], sub[1]);
5187
5188       /* If no string follows, $value gets substituted; otherwise there can
5189       be yes/no strings, as for lookup or if. */
5190
5191       switch(process_yesno(
5192                skipping,                     /* were previously skipping */
5193                lookup_value != NULL,         /* success/failure indicator */
5194                save_lookup_value,            /* value to reset for string2 */
5195                &s,                           /* input pointer */
5196                &yield,                       /* output pointer */
5197                &size,                        /* output size */
5198                &ptr,                         /* output current point */
5199                US"extract"))                 /* condition type */
5200         {
5201         case 1: goto EXPAND_FAILED;          /* when all is well, the */
5202         case 2: goto EXPAND_FAILED_CURLY;    /* returned value is 0 */
5203         }
5204
5205       /* All done - restore numerical variables. */
5206
5207       restore_expand_strings(save_expand_nmax, save_expand_nstring,
5208         save_expand_nlength);
5209
5210       continue;
5211       }
5212
5213
5214     /* Handle list operations */
5215
5216     case EITEM_FILTER:
5217     case EITEM_MAP:
5218     case EITEM_REDUCE:
5219       {
5220       int sep = 0;
5221       int save_ptr = ptr;
5222       uschar outsep[2] = { '\0', '\0' };
5223       uschar *list, *expr, *temp;
5224       uschar *save_iterate_item = iterate_item;
5225       uschar *save_lookup_value = lookup_value;
5226
5227       while (isspace(*s)) s++;
5228       if (*s++ != '{') goto EXPAND_FAILED_CURLY;
5229
5230       list = expand_string_internal(s, TRUE, &s, skipping, TRUE);
5231       if (list == NULL) goto EXPAND_FAILED;
5232       if (*s++ != '}') goto EXPAND_FAILED_CURLY;
5233
5234       if (item_type == EITEM_REDUCE)
5235         {
5236         while (isspace(*s)) s++;
5237         if (*s++ != '{') goto EXPAND_FAILED_CURLY;
5238         temp = expand_string_internal(s, TRUE, &s, skipping, TRUE);
5239         if (temp == NULL) goto EXPAND_FAILED;
5240         lookup_value = temp;
5241         if (*s++ != '}') goto EXPAND_FAILED_CURLY;
5242         }
5243
5244       while (isspace(*s)) s++;
5245       if (*s++ != '{') goto EXPAND_FAILED_CURLY;
5246
5247       expr = s;
5248
5249       /* For EITEM_FILTER, call eval_condition once, with result discarded (as
5250       if scanning a "false" part). This allows us to find the end of the
5251       condition, because if the list is empty, we won't actually evaluate the
5252       condition for real. For EITEM_MAP and EITEM_REDUCE, do the same, using
5253       the normal internal expansion function. */
5254
5255       if (item_type == EITEM_FILTER)
5256         {
5257         temp = eval_condition(expr, NULL);
5258         if (temp != NULL) s = temp;
5259         }
5260       else
5261         {
5262         temp = expand_string_internal(s, TRUE, &s, TRUE, TRUE);
5263         }
5264
5265       if (temp == NULL)
5266         {
5267         expand_string_message = string_sprintf("%s inside \"%s\" item",
5268           expand_string_message, name);
5269         goto EXPAND_FAILED;
5270         }
5271
5272       while (isspace(*s)) s++;
5273       if (*s++ != '}')
5274         {                                               /*{*/
5275         expand_string_message = string_sprintf("missing } at end of condition "
5276           "or expression inside \"%s\"", name);
5277         goto EXPAND_FAILED;
5278         }
5279
5280       while (isspace(*s)) s++;                          /*{*/
5281       if (*s++ != '}')
5282         {                                               /*{*/
5283         expand_string_message = string_sprintf("missing } at end of \"%s\"",
5284           name);
5285         goto EXPAND_FAILED;
5286         }
5287
5288       /* If we are skipping, we can now just move on to the next item. When
5289       processing for real, we perform the iteration. */
5290
5291       if (skipping) continue;
5292       while ((iterate_item = string_nextinlist(&list, &sep, NULL, 0)) != NULL)
5293         {
5294         *outsep = (uschar)sep;      /* Separator as a string */
5295
5296         DEBUG(D_expand) debug_printf("%s: $item = \"%s\"\n", name, iterate_item);
5297
5298         if (item_type == EITEM_FILTER)
5299           {
5300           BOOL condresult;
5301           if (eval_condition(expr, &condresult) == NULL)
5302             {
5303             iterate_item = save_iterate_item;
5304             lookup_value = save_lookup_value;
5305             expand_string_message = string_sprintf("%s inside \"%s\" condition",
5306               expand_string_message, name);
5307             goto EXPAND_FAILED;
5308             }
5309           DEBUG(D_expand) debug_printf("%s: condition is %s\n", name,
5310             condresult? "true":"false");
5311           if (condresult)
5312             temp = iterate_item;    /* TRUE => include this item */
5313           else
5314             continue;               /* FALSE => skip this item */
5315           }
5316
5317         /* EITEM_MAP and EITEM_REDUCE */
5318
5319         else
5320           {
5321           temp = expand_string_internal(expr, TRUE, NULL, skipping, TRUE);
5322           if (temp == NULL)
5323             {
5324             iterate_item = save_iterate_item;
5325             expand_string_message = string_sprintf("%s inside \"%s\" item",
5326               expand_string_message, name);
5327             goto EXPAND_FAILED;
5328             }
5329           if (item_type == EITEM_REDUCE)
5330             {
5331             lookup_value = temp;      /* Update the value of $value */
5332             continue;                 /* and continue the iteration */
5333             }
5334           }
5335
5336         /* We reach here for FILTER if the condition is true, always for MAP,
5337         and never for REDUCE. The value in "temp" is to be added to the output
5338         list that is being created, ensuring that any occurrences of the
5339         separator character are doubled. Unless we are dealing with the first
5340         item of the output list, add in a space if the new item begins with the
5341         separator character, or is an empty string. */
5342
5343         if (ptr != save_ptr && (temp[0] == *outsep || temp[0] == 0))
5344           yield = string_cat(yield, &size, &ptr, US" ", 1);
5345
5346         /* Add the string in "temp" to the output list that we are building,
5347         This is done in chunks by searching for the separator character. */
5348
5349         for (;;)
5350           {
5351           size_t seglen = Ustrcspn(temp, outsep);
5352             yield = string_cat(yield, &size, &ptr, temp, seglen + 1);
5353
5354           /* If we got to the end of the string we output one character
5355           too many; backup and end the loop. Otherwise arrange to double the
5356           separator. */
5357
5358           if (temp[seglen] == '\0') { ptr--; break; }
5359           yield = string_cat(yield, &size, &ptr, outsep, 1);
5360           temp += seglen + 1;
5361           }
5362
5363         /* Output a separator after the string: we will remove the redundant
5364         final one at the end. */
5365
5366         yield = string_cat(yield, &size, &ptr, outsep, 1);
5367         }   /* End of iteration over the list loop */
5368
5369       /* REDUCE has generated no output above: output the final value of
5370       $value. */
5371
5372       if (item_type == EITEM_REDUCE)
5373         {
5374         yield = string_cat(yield, &size, &ptr, lookup_value,
5375           Ustrlen(lookup_value));
5376         lookup_value = save_lookup_value;  /* Restore $value */
5377         }
5378
5379       /* FILTER and MAP generate lists: if they have generated anything, remove
5380       the redundant final separator. Even though an empty item at the end of a
5381       list does not count, this is tidier. */
5382
5383       else if (ptr != save_ptr) ptr--;
5384
5385       /* Restore preserved $item */
5386
5387       iterate_item = save_iterate_item;
5388       continue;
5389       }
5390
5391
5392     /* If ${dlfunc } support is configured, handle calling dynamically-loaded
5393     functions, unless locked out at this time. Syntax is ${dlfunc{file}{func}}
5394     or ${dlfunc{file}{func}{arg}} or ${dlfunc{file}{func}{arg1}{arg2}} or up to
5395     a maximum of EXPAND_DLFUNC_MAX_ARGS arguments (defined below). */
5396
5397     #define EXPAND_DLFUNC_MAX_ARGS 8
5398
5399     case EITEM_DLFUNC:
5400     #ifndef EXPAND_DLFUNC
5401     expand_string_message = US"\"${dlfunc\" encountered, but this facility "    /*}*/
5402       "is not included in this binary";
5403     goto EXPAND_FAILED;
5404
5405     #else   /* EXPAND_DLFUNC */
5406       {
5407       tree_node *t;
5408       exim_dlfunc_t *func;
5409       uschar *result;
5410       int status, argc;
5411       uschar *argv[EXPAND_DLFUNC_MAX_ARGS + 3];
5412
5413       if ((expand_forbid & RDO_DLFUNC) != 0)
5414         {
5415         expand_string_message =
5416           US"dynamically-loaded functions are not permitted";
5417         goto EXPAND_FAILED;
5418         }
5419
5420       switch(read_subs(argv, EXPAND_DLFUNC_MAX_ARGS + 2, 2, &s, skipping,
5421            TRUE, US"dlfunc"))
5422         {
5423         case 1: goto EXPAND_FAILED_CURLY;
5424         case 2:
5425         case 3: goto EXPAND_FAILED;
5426         }
5427
5428       /* If skipping, we don't actually do anything */
5429
5430       if (skipping) continue;
5431
5432       /* Look up the dynamically loaded object handle in the tree. If it isn't
5433       found, dlopen() the file and put the handle in the tree for next time. */
5434
5435       t = tree_search(dlobj_anchor, argv[0]);
5436       if (t == NULL)
5437         {
5438         void *handle = dlopen(CS argv[0], RTLD_LAZY);
5439         if (handle == NULL)
5440           {
5441           expand_string_message = string_sprintf("dlopen \"%s\" failed: %s",
5442             argv[0], dlerror());
5443           log_write(0, LOG_MAIN|LOG_PANIC, "%s", expand_string_message);
5444           goto EXPAND_FAILED;
5445           }
5446         t = store_get_perm(sizeof(tree_node) + Ustrlen(argv[0]));
5447         Ustrcpy(t->name, argv[0]);
5448         t->data.ptr = handle;
5449         (void)tree_insertnode(&dlobj_anchor, t);
5450         }
5451
5452       /* Having obtained the dynamically loaded object handle, look up the
5453       function pointer. */
5454
5455       func = (exim_dlfunc_t *)dlsym(t->data.ptr, CS argv[1]);
5456       if (func == NULL)
5457         {
5458         expand_string_message = string_sprintf("dlsym \"%s\" in \"%s\" failed: "
5459           "%s", argv[1], argv[0], dlerror());
5460         log_write(0, LOG_MAIN|LOG_PANIC, "%s", expand_string_message);
5461         goto EXPAND_FAILED;
5462         }
5463
5464       /* Call the function and work out what to do with the result. If it
5465       returns OK, we have a replacement string; if it returns DEFER then
5466       expansion has failed in a non-forced manner; if it returns FAIL then
5467       failure was forced; if it returns ERROR or any other value there's a
5468       problem, so panic slightly. In any case, assume that the function has
5469       side-effects on the store that must be preserved. */
5470
5471       resetok = FALSE;
5472       result = NULL;
5473       for (argc = 0; argv[argc] != NULL; argc++);
5474       status = func(&result, argc - 2, &argv[2]);
5475       if(status == OK)
5476         {
5477         if (result == NULL) result = US"";
5478         yield = string_cat(yield, &size, &ptr, result, Ustrlen(result));
5479         continue;
5480         }
5481       else
5482         {
5483         expand_string_message = result == NULL ? US"(no message)" : result;
5484         if(status == FAIL_FORCED) expand_string_forcedfail = TRUE;
5485           else if(status != FAIL)
5486             log_write(0, LOG_MAIN|LOG_PANIC, "dlfunc{%s}{%s} failed (%d): %s",
5487               argv[0], argv[1], status, expand_string_message);
5488         goto EXPAND_FAILED;
5489         }
5490       }
5491     #endif /* EXPAND_DLFUNC */
5492     }   /* EITEM_* switch */
5493
5494   /* Control reaches here if the name is not recognized as one of the more
5495   complicated expansion items. Check for the "operator" syntax (name terminated
5496   by a colon). Some of the operators have arguments, separated by _ from the
5497   name. */
5498
5499   if (*s == ':')
5500     {
5501     int c;
5502     uschar *arg = NULL;
5503     uschar *sub = expand_string_internal(s+1, TRUE, &s, skipping, TRUE);
5504     if (sub == NULL) goto EXPAND_FAILED;
5505     s++;
5506
5507     /* Owing to an historical mis-design, an underscore may be part of the
5508     operator name, or it may introduce arguments.  We therefore first scan the
5509     table of names that contain underscores. If there is no match, we cut off
5510     the arguments and then scan the main table. */
5511
5512     c = chop_match(name, op_table_underscore,
5513       sizeof(op_table_underscore)/sizeof(uschar *));
5514
5515     if (c < 0)
5516       {
5517       arg = Ustrchr(name, '_');
5518       if (arg != NULL) *arg = 0;
5519       c = chop_match(name, op_table_main,
5520         sizeof(op_table_main)/sizeof(uschar *));
5521       if (c >= 0) c += sizeof(op_table_underscore)/sizeof(uschar *);
5522       if (arg != NULL) *arg++ = '_';   /* Put back for error messages */
5523       }
5524
5525     /* If we are skipping, we don't need to perform the operation at all.
5526     This matters for operations like "mask", because the data may not be
5527     in the correct format when skipping. For example, the expression may test
5528     for the existence of $sender_host_address before trying to mask it. For
5529     other operations, doing them may not fail, but it is a waste of time. */
5530
5531     if (skipping && c >= 0) continue;
5532
5533     /* Otherwise, switch on the operator type */
5534
5535     switch(c)
5536       {
5537       case EOP_BASE62:
5538         {
5539         uschar *t;
5540         unsigned long int n = Ustrtoul(sub, &t, 10);
5541         if (*t != 0)
5542           {
5543           expand_string_message = string_sprintf("argument for base62 "
5544             "operator is \"%s\", which is not a decimal number", sub);
5545           goto EXPAND_FAILED;
5546           }
5547         t = string_base62(n);
5548         yield = string_cat(yield, &size, &ptr, t, Ustrlen(t));
5549         continue;
5550         }
5551
5552       /* Note that for Darwin and Cygwin, BASE_62 actually has the value 36 */
5553
5554       case EOP_BASE62D:
5555         {
5556         uschar buf[16];
5557         uschar *tt = sub;
5558         unsigned long int n = 0;
5559         while (*tt != 0)
5560           {
5561           uschar *t = Ustrchr(base62_chars, *tt++);
5562           if (t == NULL)
5563             {
5564             expand_string_message = string_sprintf("argument for base62d "
5565               "operator is \"%s\", which is not a base %d number", sub,
5566               BASE_62);
5567             goto EXPAND_FAILED;
5568             }
5569           n = n * BASE_62 + (t - base62_chars);
5570           }
5571         (void)sprintf(CS buf, "%ld", n);
5572         yield = string_cat(yield, &size, &ptr, buf, Ustrlen(buf));
5573         continue;
5574         }
5575
5576       case EOP_EXPAND:
5577         {
5578         uschar *expanded = expand_string_internal(sub, FALSE, NULL, skipping, TRUE);
5579         if (expanded == NULL)
5580           {
5581           expand_string_message =
5582             string_sprintf("internal expansion of \"%s\" failed: %s", sub,
5583               expand_string_message);
5584           goto EXPAND_FAILED;
5585           }
5586         yield = string_cat(yield, &size, &ptr, expanded, Ustrlen(expanded));
5587         continue;
5588         }
5589
5590       case EOP_LC:
5591         {
5592         int count = 0;
5593         uschar *t = sub - 1;
5594         while (*(++t) != 0) { *t = tolower(*t); count++; }
5595         yield = string_cat(yield, &size, &ptr, sub, count);
5596         continue;
5597         }
5598
5599       case EOP_UC:
5600         {
5601         int count = 0;
5602         uschar *t = sub - 1;
5603         while (*(++t) != 0) { *t = toupper(*t); count++; }
5604         yield = string_cat(yield, &size, &ptr, sub, count);
5605         continue;
5606         }
5607
5608       case EOP_MD5:
5609         {
5610         md5 base;
5611         uschar digest[16];
5612         int j;
5613         char st[33];
5614         md5_start(&base);
5615         md5_end(&base, sub, Ustrlen(sub), digest);
5616         for(j = 0; j < 16; j++) sprintf(st+2*j, "%02x", digest[j]);
5617         yield = string_cat(yield, &size, &ptr, US st, (int)strlen(st));
5618         continue;
5619         }
5620
5621       case EOP_SHA1:
5622         {
5623         sha1 base;
5624         uschar digest[20];
5625         int j;
5626         char st[41];
5627         sha1_start(&base);
5628         sha1_end(&base, sub, Ustrlen(sub), digest);
5629         for(j = 0; j < 20; j++) sprintf(st+2*j, "%02X", digest[j]);
5630         yield = string_cat(yield, &size, &ptr, US st, (int)strlen(st));
5631         continue;
5632         }
5633
5634       /* Convert hex encoding to base64 encoding */
5635
5636       case EOP_HEX2B64:
5637         {
5638         int c = 0;
5639         int b = -1;
5640         uschar *in = sub;
5641         uschar *out = sub;
5642         uschar *enc;
5643
5644         for (enc = sub; *enc != 0; enc++)
5645           {
5646           if (!isxdigit(*enc))
5647             {
5648             expand_string_message = string_sprintf("\"%s\" is not a hex "
5649               "string", sub);
5650             goto EXPAND_FAILED;
5651             }
5652           c++;
5653           }
5654
5655         if ((c & 1) != 0)
5656           {
5657           expand_string_message = string_sprintf("\"%s\" contains an odd "
5658             "number of characters", sub);
5659           goto EXPAND_FAILED;
5660           }
5661
5662         while ((c = *in++) != 0)
5663           {
5664           if (isdigit(c)) c -= '0';
5665           else c = toupper(c) - 'A' + 10;
5666           if (b == -1)
5667             {
5668             b = c << 4;
5669             }
5670           else
5671             {
5672             *out++ = b | c;
5673             b = -1;
5674             }
5675           }
5676
5677         enc = auth_b64encode(sub, out - sub);
5678         yield = string_cat(yield, &size, &ptr, enc, Ustrlen(enc));
5679         continue;
5680         }
5681
5682       /* Convert octets outside 0x21..0x7E to \xXX form */
5683
5684       case EOP_HEXQUOTE:
5685         {
5686         uschar *t = sub - 1;
5687         while (*(++t) != 0)
5688           {
5689           if (*t < 0x21 || 0x7E < *t)
5690             yield = string_cat(yield, &size, &ptr,
5691               string_sprintf("\\x%02x", *t), 4);
5692           else
5693             yield = string_cat(yield, &size, &ptr, t, 1);
5694           }
5695         continue;
5696         }
5697
5698       /* count the number of list elements */
5699
5700       case EOP_LISTCOUNT:
5701         {
5702         int cnt = 0;
5703         int sep = 0;
5704         uschar * cp;
5705         uschar buffer[256];
5706
5707         while (string_nextinlist(&sub, &sep, buffer, sizeof(buffer)) != NULL) cnt++;
5708         cp = string_sprintf("%d", cnt);
5709         yield = string_cat(yield, &size, &ptr, cp, Ustrlen(cp));
5710         continue;
5711         }
5712
5713       /* expand a named list given the name */
5714       /* handles nested named lists; requotes as colon-sep list */
5715
5716       case EOP_LISTNAMED:
5717         {
5718         tree_node *t = NULL;
5719         uschar * list;
5720         int sep = 0;
5721         uschar * item;
5722         uschar * suffix = US"";
5723         BOOL needsep = FALSE;
5724         uschar buffer[256];
5725
5726         if (*sub == '+') sub++;
5727         if (arg == NULL)        /* no-argument version */
5728           {
5729           if (!(t = tree_search(addresslist_anchor, sub)) &&
5730               !(t = tree_search(domainlist_anchor,  sub)) &&
5731               !(t = tree_search(hostlist_anchor,    sub)))
5732             t = tree_search(localpartlist_anchor, sub);
5733           }
5734         else switch(*arg)       /* specific list-type version */
5735           {
5736           case 'a': t = tree_search(addresslist_anchor,   sub); suffix = US"_a"; break;
5737           case 'd': t = tree_search(domainlist_anchor,    sub); suffix = US"_d"; break;
5738           case 'h': t = tree_search(hostlist_anchor,      sub); suffix = US"_h"; break;
5739           case 'l': t = tree_search(localpartlist_anchor, sub); suffix = US"_l"; break;
5740           default:
5741             expand_string_message = string_sprintf("bad suffix on \"list\" operator");
5742             goto EXPAND_FAILED;
5743           }
5744
5745         if(!t)
5746           {
5747           expand_string_message = string_sprintf("\"%s\" is not a %snamed list",
5748             sub, !arg?""
5749               : *arg=='a'?"address "
5750               : *arg=='d'?"domain "
5751               : *arg=='h'?"host "
5752               : *arg=='l'?"localpart "
5753               : 0);
5754           goto EXPAND_FAILED;
5755           }
5756
5757         list = ((namedlist_block *)(t->data.ptr))->string;
5758
5759         while ((item = string_nextinlist(&list, &sep, buffer, sizeof(buffer))) != NULL)
5760           {
5761           uschar * buf = US" : ";
5762           if (needsep)
5763             yield = string_cat(yield, &size, &ptr, buf, 3);
5764           else
5765             needsep = TRUE;
5766
5767           if (*item == '+')     /* list item is itself a named list */
5768             {
5769             uschar * sub = string_sprintf("${listnamed%s:%s}", suffix, item);
5770             item = expand_string_internal(sub, FALSE, NULL, FALSE, TRUE);
5771             }
5772           else if (sep != ':')  /* item from non-colon-sep list, re-quote for colon list-separator */
5773             {
5774             char * cp;
5775             char tok[3];
5776             tok[0] = sep; tok[1] = ':'; tok[2] = 0;
5777             while ((cp= strpbrk((const char *)item, tok)))
5778               {
5779               yield = string_cat(yield, &size, &ptr, item, cp-(char *)item);
5780               if (*cp++ == ':') /* colon in a non-colon-sep list item, needs doubling */
5781                 {
5782                 yield = string_cat(yield, &size, &ptr, US"::", 2);
5783                 item = (uschar *)cp;
5784                 }
5785               else              /* sep in item; should already be doubled; emit once */
5786                 {
5787                 yield = string_cat(yield, &size, &ptr, (uschar *)tok, 1);
5788                 if (*cp == sep) cp++;
5789                 item = (uschar *)cp;
5790                 }
5791               }
5792             }
5793           yield = string_cat(yield, &size, &ptr, item, Ustrlen(item));
5794           }
5795         continue;
5796         }
5797
5798       /* mask applies a mask to an IP address; for example the result of
5799       ${mask:131.111.10.206/28} is 131.111.10.192/28. */
5800
5801       case EOP_MASK:
5802         {
5803         int count;
5804         uschar *endptr;
5805         int binary[4];
5806         int mask, maskoffset;
5807         int type = string_is_ip_address(sub, &maskoffset);
5808         uschar buffer[64];
5809
5810         if (type == 0)
5811           {
5812           expand_string_message = string_sprintf("\"%s\" is not an IP address",
5813            sub);
5814           goto EXPAND_FAILED;
5815           }
5816
5817         if (maskoffset == 0)
5818           {
5819           expand_string_message = string_sprintf("missing mask value in \"%s\"",
5820             sub);
5821           goto EXPAND_FAILED;
5822           }
5823
5824         mask = Ustrtol(sub + maskoffset + 1, &endptr, 10);
5825
5826         if (*endptr != 0 || mask < 0 || mask > ((type == 4)? 32 : 128))
5827           {
5828           expand_string_message = string_sprintf("mask value too big in \"%s\"",
5829             sub);
5830           goto EXPAND_FAILED;
5831           }
5832
5833         /* Convert the address to binary integer(s) and apply the mask */
5834
5835         sub[maskoffset] = 0;
5836         count = host_aton(sub, binary);
5837         host_mask(count, binary, mask);
5838
5839         /* Convert to masked textual format and add to output. */
5840
5841         yield = string_cat(yield, &size, &ptr, buffer,
5842           host_nmtoa(count, binary, mask, buffer, '.'));
5843         continue;
5844         }
5845
5846       case EOP_ADDRESS:
5847       case EOP_LOCAL_PART:
5848       case EOP_DOMAIN:
5849         {
5850         uschar *error;
5851         int start, end, domain;
5852         uschar *t = parse_extract_address(sub, &error, &start, &end, &domain,
5853           FALSE);
5854         if (t != NULL)
5855           {
5856           if (c != EOP_DOMAIN)
5857             {
5858             if (c == EOP_LOCAL_PART && domain != 0) end = start + domain - 1;
5859             yield = string_cat(yield, &size, &ptr, sub+start, end-start);
5860             }
5861           else if (domain != 0)
5862             {
5863             domain += start;
5864             yield = string_cat(yield, &size, &ptr, sub+domain, end-domain);
5865             }
5866           }
5867         continue;
5868         }
5869
5870       case EOP_ADDRESSES:
5871         {
5872         uschar outsep[2] = { ':', '\0' };
5873         uschar *address, *error;
5874         int save_ptr = ptr;
5875         int start, end, domain;  /* Not really used */
5876
5877         while (isspace(*sub)) sub++;
5878         if (*sub == '>') { *outsep = *++sub; ++sub; }
5879         parse_allow_group = TRUE;
5880
5881         for (;;)
5882           {
5883           uschar *p = parse_find_address_end(sub, FALSE);
5884           uschar saveend = *p;
5885           *p = '\0';
5886           address = parse_extract_address(sub, &error, &start, &end, &domain,
5887             FALSE);
5888           *p = saveend;
5889
5890           /* Add the address to the output list that we are building. This is
5891           done in chunks by searching for the separator character. At the
5892           start, unless we are dealing with the first address of the output
5893           list, add in a space if the new address begins with the separator
5894           character, or is an empty string. */
5895
5896           if (address != NULL)
5897             {
5898             if (ptr != save_ptr && address[0] == *outsep)
5899               yield = string_cat(yield, &size, &ptr, US" ", 1);
5900
5901             for (;;)
5902               {
5903               size_t seglen = Ustrcspn(address, outsep);
5904               yield = string_cat(yield, &size, &ptr, address, seglen + 1);
5905
5906               /* If we got to the end of the string we output one character
5907               too many. */
5908
5909               if (address[seglen] == '\0') { ptr--; break; }
5910               yield = string_cat(yield, &size, &ptr, outsep, 1);
5911               address += seglen + 1;
5912               }
5913
5914             /* Output a separator after the string: we will remove the
5915             redundant final one at the end. */
5916
5917             yield = string_cat(yield, &size, &ptr, outsep, 1);
5918             }
5919
5920           if (saveend == '\0') break;
5921           sub = p + 1;
5922           }
5923
5924         /* If we have generated anything, remove the redundant final
5925         separator. */
5926
5927         if (ptr != save_ptr) ptr--;
5928         parse_allow_group = FALSE;
5929         continue;
5930         }
5931
5932
5933       /* quote puts a string in quotes if it is empty or contains anything
5934       other than alphamerics, underscore, dot, or hyphen.
5935
5936       quote_local_part puts a string in quotes if RFC 2821/2822 requires it to
5937       be quoted in order to be a valid local part.
5938
5939       In both cases, newlines and carriage returns are converted into \n and \r
5940       respectively */
5941
5942       case EOP_QUOTE:
5943       case EOP_QUOTE_LOCAL_PART:
5944       if (arg == NULL)
5945         {
5946         BOOL needs_quote = (*sub == 0);      /* TRUE for empty string */
5947         uschar *t = sub - 1;
5948
5949         if (c == EOP_QUOTE)
5950           {
5951           while (!needs_quote && *(++t) != 0)
5952             needs_quote = !isalnum(*t) && !strchr("_-.", *t);
5953           }
5954         else  /* EOP_QUOTE_LOCAL_PART */
5955           {
5956           while (!needs_quote && *(++t) != 0)
5957             needs_quote = !isalnum(*t) &&
5958               strchr("!#$%&'*+-/=?^_`{|}~", *t) == NULL &&
5959               (*t != '.' || t == sub || t[1] == 0);
5960           }
5961
5962         if (needs_quote)
5963           {
5964           yield = string_cat(yield, &size, &ptr, US"\"", 1);
5965           t = sub - 1;
5966           while (*(++t) != 0)
5967             {
5968             if (*t == '\n')
5969               yield = string_cat(yield, &size, &ptr, US"\\n", 2);
5970             else if (*t == '\r')
5971               yield = string_cat(yield, &size, &ptr, US"\\r", 2);
5972             else
5973               {
5974               if (*t == '\\' || *t == '"')
5975                 yield = string_cat(yield, &size, &ptr, US"\\", 1);
5976               yield = string_cat(yield, &size, &ptr, t, 1);
5977               }
5978             }
5979           yield = string_cat(yield, &size, &ptr, US"\"", 1);
5980           }
5981         else yield = string_cat(yield, &size, &ptr, sub, Ustrlen(sub));
5982         continue;
5983         }
5984
5985       /* quote_lookuptype does lookup-specific quoting */
5986
5987       else
5988         {
5989         int n;
5990         uschar *opt = Ustrchr(arg, '_');
5991
5992         if (opt != NULL) *opt++ = 0;
5993
5994         n = search_findtype(arg, Ustrlen(arg));
5995         if (n < 0)
5996           {
5997           expand_string_message = search_error_message;
5998           goto EXPAND_FAILED;
5999           }
6000
6001         if (lookup_list[n]->quote != NULL)
6002           sub = (lookup_list[n]->quote)(sub, opt);
6003         else if (opt != NULL) sub = NULL;
6004
6005         if (sub == NULL)
6006           {
6007           expand_string_message = string_sprintf(
6008             "\"%s\" unrecognized after \"${quote_%s\"",
6009             opt, arg);
6010           goto EXPAND_FAILED;
6011           }
6012
6013         yield = string_cat(yield, &size, &ptr, sub, Ustrlen(sub));
6014         continue;
6015         }
6016
6017       /* rx quote sticks in \ before any non-alphameric character so that
6018       the insertion works in a regular expression. */
6019
6020       case EOP_RXQUOTE:
6021         {
6022         uschar *t = sub - 1;
6023         while (*(++t) != 0)
6024           {
6025           if (!isalnum(*t))
6026             yield = string_cat(yield, &size, &ptr, US"\\", 1);
6027           yield = string_cat(yield, &size, &ptr, t, 1);
6028           }
6029         continue;
6030         }
6031
6032       /* RFC 2047 encodes, assuming headers_charset (default ISO 8859-1) as
6033       prescribed by the RFC, if there are characters that need to be encoded */
6034
6035       case EOP_RFC2047:
6036         {
6037         uschar buffer[2048];
6038         uschar *string = parse_quote_2047(sub, Ustrlen(sub), headers_charset,
6039           buffer, sizeof(buffer), FALSE);
6040         yield = string_cat(yield, &size, &ptr, string, Ustrlen(string));
6041         continue;
6042         }
6043
6044       /* RFC 2047 decode */
6045
6046       case EOP_RFC2047D:
6047         {
6048         int len;
6049         uschar *error;
6050         uschar *decoded = rfc2047_decode(sub, check_rfc2047_length,
6051           headers_charset, '?', &len, &error);
6052         if (error != NULL)
6053           {
6054           expand_string_message = error;
6055           goto EXPAND_FAILED;
6056           }
6057         yield = string_cat(yield, &size, &ptr, decoded, len);
6058         continue;
6059         }
6060
6061       /* from_utf8 converts UTF-8 to 8859-1, turning non-existent chars into
6062       underscores */
6063
6064       case EOP_FROM_UTF8:
6065         {
6066         while (*sub != 0)
6067           {
6068           int c;
6069           uschar buff[4];
6070           GETUTF8INC(c, sub);
6071           if (c > 255) c = '_';
6072           buff[0] = c;
6073           yield = string_cat(yield, &size, &ptr, buff, 1);
6074           }
6075         continue;
6076         }
6077
6078       /* escape turns all non-printing characters into escape sequences. */
6079
6080       case EOP_ESCAPE:
6081         {
6082         uschar *t = string_printing(sub);
6083         yield = string_cat(yield, &size, &ptr, t, Ustrlen(t));
6084         continue;
6085         }
6086
6087       /* Handle numeric expression evaluation */
6088
6089       case EOP_EVAL:
6090       case EOP_EVAL10:
6091         {
6092         uschar *save_sub = sub;
6093         uschar *error = NULL;
6094         int_eximarith_t n = eval_expr(&sub, (c == EOP_EVAL10), &error, FALSE);
6095         if (error != NULL)
6096           {
6097           expand_string_message = string_sprintf("error in expression "
6098             "evaluation: %s (after processing \"%.*s\")", error, sub-save_sub,
6099               save_sub);
6100           goto EXPAND_FAILED;
6101           }
6102         sprintf(CS var_buffer, PR_EXIM_ARITH, n);
6103         yield = string_cat(yield, &size, &ptr, var_buffer, Ustrlen(var_buffer));
6104         continue;
6105         }
6106
6107       /* Handle time period formating */
6108
6109       case EOP_TIME_EVAL:
6110         {
6111         int n = readconf_readtime(sub, 0, FALSE);
6112         if (n < 0)
6113           {
6114           expand_string_message = string_sprintf("string \"%s\" is not an "
6115             "Exim time interval in \"%s\" operator", sub, name);
6116           goto EXPAND_FAILED;
6117           }
6118         sprintf(CS var_buffer, "%d", n);
6119         yield = string_cat(yield, &size, &ptr, var_buffer, Ustrlen(var_buffer));
6120         continue;
6121         }
6122
6123       case EOP_TIME_INTERVAL:
6124         {
6125         int n;
6126         uschar *t = read_number(&n, sub);
6127         if (*t != 0) /* Not A Number*/
6128           {
6129           expand_string_message = string_sprintf("string \"%s\" is not a "
6130             "positive number in \"%s\" operator", sub, name);
6131           goto EXPAND_FAILED;
6132           }
6133         t = readconf_printtime(n);
6134         yield = string_cat(yield, &size, &ptr, t, Ustrlen(t));
6135         continue;
6136         }
6137
6138       /* Convert string to base64 encoding */
6139
6140       case EOP_STR2B64:
6141         {
6142         uschar *encstr = auth_b64encode(sub, Ustrlen(sub));
6143         yield = string_cat(yield, &size, &ptr, encstr, Ustrlen(encstr));
6144         continue;
6145         }
6146
6147       /* strlen returns the length of the string */
6148
6149       case EOP_STRLEN:
6150         {
6151         uschar buff[24];
6152         (void)sprintf(CS buff, "%d", Ustrlen(sub));
6153         yield = string_cat(yield, &size, &ptr, buff, Ustrlen(buff));
6154         continue;
6155         }
6156
6157       /* length_n or l_n takes just the first n characters or the whole string,
6158       whichever is the shorter;
6159
6160       substr_m_n, and s_m_n take n characters from offset m; negative m take
6161       from the end; l_n is synonymous with s_0_n. If n is omitted in substr it
6162       takes the rest, either to the right or to the left.
6163
6164       hash_n or h_n makes a hash of length n from the string, yielding n
6165       characters from the set a-z; hash_n_m makes a hash of length n, but
6166       uses m characters from the set a-zA-Z0-9.
6167
6168       nhash_n returns a single number between 0 and n-1 (in text form), while
6169       nhash_n_m returns a div/mod hash as two numbers "a/b". The first lies
6170       between 0 and n-1 and the second between 0 and m-1. */
6171
6172       case EOP_LENGTH:
6173       case EOP_L:
6174       case EOP_SUBSTR:
6175       case EOP_S:
6176       case EOP_HASH:
6177       case EOP_H:
6178       case EOP_NHASH:
6179       case EOP_NH:
6180         {
6181         int sign = 1;
6182         int value1 = 0;
6183         int value2 = -1;
6184         int *pn;
6185         int len;
6186         uschar *ret;
6187
6188         if (arg == NULL)
6189           {
6190           expand_string_message = string_sprintf("missing values after %s",
6191             name);
6192           goto EXPAND_FAILED;
6193           }
6194
6195         /* "length" has only one argument, effectively being synonymous with
6196         substr_0_n. */
6197
6198         if (c == EOP_LENGTH || c == EOP_L)
6199           {
6200           pn = &value2;
6201           value2 = 0;
6202           }
6203
6204         /* The others have one or two arguments; for "substr" the first may be
6205         negative. The second being negative means "not supplied". */
6206
6207         else
6208           {
6209           pn = &value1;
6210           if (name[0] == 's' && *arg == '-') { sign = -1; arg++; }
6211           }
6212
6213         /* Read up to two numbers, separated by underscores */
6214
6215         ret = arg;
6216         while (*arg != 0)
6217           {
6218           if (arg != ret && *arg == '_' && pn == &value1)
6219             {
6220             pn = &value2;
6221             value2 = 0;
6222             if (arg[1] != 0) arg++;
6223             }
6224           else if (!isdigit(*arg))
6225             {
6226             expand_string_message =
6227               string_sprintf("non-digit after underscore in \"%s\"", name);
6228             goto EXPAND_FAILED;
6229             }
6230           else *pn = (*pn)*10 + *arg++ - '0';
6231           }
6232         value1 *= sign;
6233
6234         /* Perform the required operation */
6235
6236         ret =
6237           (c == EOP_HASH || c == EOP_H)?
6238              compute_hash(sub, value1, value2, &len) :
6239           (c == EOP_NHASH || c == EOP_NH)?
6240              compute_nhash(sub, value1, value2, &len) :
6241              extract_substr(sub, value1, value2, &len);
6242
6243         if (ret == NULL) goto EXPAND_FAILED;
6244         yield = string_cat(yield, &size, &ptr, ret, len);
6245         continue;
6246         }
6247
6248       /* Stat a path */
6249
6250       case EOP_STAT:
6251         {
6252         uschar *s;
6253         uschar smode[12];
6254         uschar **modetable[3];
6255         int i;
6256         mode_t mode;
6257         struct stat st;
6258
6259         if ((expand_forbid & RDO_EXISTS) != 0)
6260           {
6261           expand_string_message = US"Use of the stat() expansion is not permitted";
6262           goto EXPAND_FAILED;
6263           }
6264
6265         if (stat(CS sub, &st) < 0)
6266           {
6267           expand_string_message = string_sprintf("stat(%s) failed: %s",
6268             sub, strerror(errno));
6269           goto EXPAND_FAILED;
6270           }
6271         mode = st.st_mode;
6272         switch (mode & S_IFMT)
6273           {
6274           case S_IFIFO: smode[0] = 'p'; break;
6275           case S_IFCHR: smode[0] = 'c'; break;
6276           case S_IFDIR: smode[0] = 'd'; break;
6277           case S_IFBLK: smode[0] = 'b'; break;
6278           case S_IFREG: smode[0] = '-'; break;
6279           default: smode[0] = '?'; break;
6280           }
6281
6282         modetable[0] = ((mode & 01000) == 0)? mtable_normal : mtable_sticky;
6283         modetable[1] = ((mode & 02000) == 0)? mtable_normal : mtable_setid;
6284         modetable[2] = ((mode & 04000) == 0)? mtable_normal : mtable_setid;
6285
6286         for (i = 0; i < 3; i++)
6287           {
6288           memcpy(CS(smode + 7 - i*3), CS(modetable[i][mode & 7]), 3);
6289           mode >>= 3;
6290           }
6291
6292         smode[10] = 0;
6293         s = string_sprintf("mode=%04lo smode=%s inode=%ld device=%ld links=%ld "
6294           "uid=%ld gid=%ld size=" OFF_T_FMT " atime=%ld mtime=%ld ctime=%ld",
6295           (long)(st.st_mode & 077777), smode, (long)st.st_ino,
6296           (long)st.st_dev, (long)st.st_nlink, (long)st.st_uid,
6297           (long)st.st_gid, st.st_size, (long)st.st_atime,
6298           (long)st.st_mtime, (long)st.st_ctime);
6299         yield = string_cat(yield, &size, &ptr, s, Ustrlen(s));
6300         continue;
6301         }
6302
6303       /* vaguely random number less than N */
6304
6305       case EOP_RANDINT:
6306         {
6307         int_eximarith_t max;
6308         uschar *s;
6309
6310         max = expand_string_integer(sub, TRUE);
6311         if (expand_string_message != NULL)
6312           goto EXPAND_FAILED;
6313         s = string_sprintf("%d", vaguely_random_number((int)max));
6314         yield = string_cat(yield, &size, &ptr, s, Ustrlen(s));
6315         continue;
6316         }
6317
6318       /* Reverse IP, including IPv6 to dotted-nibble */
6319
6320       case EOP_REVERSE_IP:
6321         {
6322         int family, maskptr;
6323         uschar reversed[128];
6324
6325         family = string_is_ip_address(sub, &maskptr);
6326         if (family == 0)
6327           {
6328           expand_string_message = string_sprintf(
6329               "reverse_ip() not given an IP address [%s]", sub);
6330           goto EXPAND_FAILED;
6331           }
6332         invert_address(reversed, sub);
6333         yield = string_cat(yield, &size, &ptr, reversed, Ustrlen(reversed));
6334         continue;
6335         }
6336
6337       /* Unknown operator */
6338
6339       default:
6340       expand_string_message =
6341         string_sprintf("unknown expansion operator \"%s\"", name);
6342       goto EXPAND_FAILED;
6343       }
6344     }
6345
6346   /* Handle a plain name. If this is the first thing in the expansion, release
6347   the pre-allocated buffer. If the result data is known to be in a new buffer,
6348   newsize will be set to the size of that buffer, and we can just point at that
6349   store instead of copying. Many expansion strings contain just one reference,
6350   so this is a useful optimization, especially for humungous headers
6351   ($message_headers). */
6352                                                 /*{*/
6353   if (*s++ == '}')
6354     {
6355     int len;
6356     int newsize = 0;
6357     if (ptr == 0)
6358       {
6359       if (resetok) store_reset(yield);
6360       yield = NULL;
6361       size = 0;
6362       }
6363     value = find_variable(name, FALSE, skipping, &newsize);
6364     if (value == NULL)
6365       {
6366       expand_string_message =
6367         string_sprintf("unknown variable in \"${%s}\"", name);
6368       check_variable_error_message(name);
6369       goto EXPAND_FAILED;
6370       }
6371     len = Ustrlen(value);
6372     if (yield == NULL && newsize != 0)
6373       {
6374       yield = value;
6375       size = newsize;
6376       ptr = len;
6377       }
6378     else yield = string_cat(yield, &size, &ptr, value, len);
6379     continue;
6380     }
6381
6382   /* Else there's something wrong */
6383
6384   expand_string_message =
6385     string_sprintf("\"${%s\" is not a known operator (or a } is missing "
6386     "in a variable reference)", name);
6387   goto EXPAND_FAILED;
6388   }
6389
6390 /* If we hit the end of the string when ket_ends is set, there is a missing
6391 terminating brace. */
6392
6393 if (ket_ends && *s == 0)
6394   {
6395   expand_string_message = malformed_header?
6396     US"missing } at end of string - could be header name not terminated by colon"
6397     :
6398     US"missing } at end of string";
6399   goto EXPAND_FAILED;
6400   }
6401
6402 /* Expansion succeeded; yield may still be NULL here if nothing was actually
6403 added to the string. If so, set up an empty string. Add a terminating zero. If
6404 left != NULL, return a pointer to the terminator. */
6405
6406 if (yield == NULL) yield = store_get(1);
6407 yield[ptr] = 0;
6408 if (left != NULL) *left = s;
6409
6410 /* Any stacking store that was used above the final string is no longer needed.
6411 In many cases the final string will be the first one that was got and so there
6412 will be optimal store usage. */
6413
6414 if (resetok) store_reset(yield + ptr + 1);
6415 DEBUG(D_expand)
6416   {
6417   debug_printf("expanding: %.*s\n   result: %s\n", (int)(s - string), string,
6418     yield);
6419   if (skipping) debug_printf("skipping: result is not used\n");
6420   }
6421 return yield;
6422
6423 /* This is the failure exit: easiest to program with a goto. We still need
6424 to update the pointer to the terminator, for cases of nested calls with "fail".
6425 */
6426
6427 EXPAND_FAILED_CURLY:
6428 expand_string_message = malformed_header?
6429   US"missing or misplaced { or } - could be header name not terminated by colon"
6430   :
6431   US"missing or misplaced { or }";
6432
6433 /* At one point, Exim reset the store to yield (if yield was not NULL), but
6434 that is a bad idea, because expand_string_message is in dynamic store. */
6435
6436 EXPAND_FAILED:
6437 if (left != NULL) *left = s;
6438 DEBUG(D_expand)
6439   {
6440   debug_printf("failed to expand: %s\n", string);
6441   debug_printf("   error message: %s\n", expand_string_message);
6442   if (expand_string_forcedfail) debug_printf("failure was forced\n");
6443   }
6444 return NULL;
6445 }
6446
6447
6448 /* This is the external function call. Do a quick check for any expansion
6449 metacharacters, and if there are none, just return the input string.
6450
6451 Argument: the string to be expanded
6452 Returns:  the expanded string, or NULL if expansion failed; if failure was
6453           due to a lookup deferring, search_find_defer will be TRUE
6454 */
6455
6456 uschar *
6457 expand_string(uschar *string)
6458 {
6459 search_find_defer = FALSE;
6460 malformed_header = FALSE;
6461 return (Ustrpbrk(string, "$\\") == NULL)? string :
6462   expand_string_internal(string, FALSE, NULL, FALSE, TRUE);
6463 }
6464
6465
6466
6467 /*************************************************
6468 *              Expand and copy                   *
6469 *************************************************/
6470
6471 /* Now and again we want to expand a string and be sure that the result is in a
6472 new bit of store. This function does that.
6473
6474 Argument: the string to be expanded
6475 Returns:  the expanded string, always in a new bit of store, or NULL
6476 */
6477
6478 uschar *
6479 expand_string_copy(uschar *string)
6480 {
6481 uschar *yield = expand_string(string);
6482 if (yield == string) yield = string_copy(string);
6483 return yield;
6484 }
6485
6486
6487
6488 /*************************************************
6489 *        Expand and interpret as an integer      *
6490 *************************************************/
6491
6492 /* Expand a string, and convert the result into an integer.
6493
6494 Arguments:
6495   string  the string to be expanded
6496   isplus  TRUE if a non-negative number is expected
6497
6498 Returns:  the integer value, or
6499           -1 for an expansion error               ) in both cases, message in
6500           -2 for an integer interpretation error  ) expand_string_message
6501           expand_string_message is set NULL for an OK integer
6502 */
6503
6504 int_eximarith_t
6505 expand_string_integer(uschar *string, BOOL isplus)
6506 {
6507 int_eximarith_t value;
6508 uschar *s = expand_string(string);
6509 uschar *msg = US"invalid integer \"%s\"";
6510 uschar *endptr;
6511
6512 /* If expansion failed, expand_string_message will be set. */
6513
6514 if (s == NULL) return -1;
6515
6516 /* On an overflow, strtol() returns LONG_MAX or LONG_MIN, and sets errno
6517 to ERANGE. When there isn't an overflow, errno is not changed, at least on some
6518 systems, so we set it zero ourselves. */
6519
6520 errno = 0;
6521 expand_string_message = NULL;               /* Indicates no error */
6522
6523 /* Before Exim 4.64, strings consisting entirely of whitespace compared
6524 equal to 0.  Unfortunately, people actually relied upon that, so preserve
6525 the behaviour explicitly.  Stripping leading whitespace is a harmless
6526 noop change since strtol skips it anyway (provided that there is a number
6527 to find at all). */
6528 if (isspace(*s))
6529   {
6530   while (isspace(*s)) ++s;
6531   if (*s == '\0')
6532     {
6533       DEBUG(D_expand)
6534        debug_printf("treating blank string as number 0\n");
6535       return 0;
6536     }
6537   }
6538
6539 value = strtoll(CS s, CSS &endptr, 10);
6540
6541 if (endptr == s)
6542   {
6543   msg = US"integer expected but \"%s\" found";
6544   }
6545 else if (value < 0 && isplus)
6546   {
6547   msg = US"non-negative integer expected but \"%s\" found";
6548   }
6549 else
6550   {
6551   switch (tolower(*endptr))
6552     {
6553     default:
6554       break;
6555     case 'k':
6556       if (value > EXIM_ARITH_MAX/1024 || value < EXIM_ARITH_MIN/1024) errno = ERANGE;
6557       else value *= 1024;
6558       endptr++;
6559       break;
6560     case 'm':
6561       if (value > EXIM_ARITH_MAX/(1024*1024) || value < EXIM_ARITH_MIN/(1024*1024)) errno = ERANGE;
6562       else value *= 1024*1024;
6563       endptr++;
6564       break;
6565     case 'g':
6566       if (value > EXIM_ARITH_MAX/(1024*1024*1024) || value < EXIM_ARITH_MIN/(1024*1024*1024)) errno = ERANGE;
6567       else value *= 1024*1024*1024;
6568       endptr++;
6569       break;
6570     }
6571   if (errno == ERANGE)
6572     msg = US"absolute value of integer \"%s\" is too large (overflow)";
6573   else
6574     {
6575     while (isspace(*endptr)) endptr++;
6576     if (*endptr == 0) return value;
6577     }
6578   }
6579
6580 expand_string_message = string_sprintf(CS msg, s);
6581 return -2;
6582 }
6583
6584
6585 /*************************************************
6586 **************************************************
6587 *             Stand-alone test program           *
6588 **************************************************
6589 *************************************************/
6590
6591 #ifdef STAND_ALONE
6592
6593
6594 BOOL
6595 regex_match_and_setup(const pcre *re, uschar *subject, int options, int setup)
6596 {
6597 int ovector[3*(EXPAND_MAXN+1)];
6598 int n = pcre_exec(re, NULL, subject, Ustrlen(subject), 0, PCRE_EOPT|options,
6599   ovector, sizeof(ovector)/sizeof(int));
6600 BOOL yield = n >= 0;
6601 if (n == 0) n = EXPAND_MAXN + 1;
6602 if (yield)
6603   {
6604   int nn;
6605   expand_nmax = (setup < 0)? 0 : setup + 1;
6606   for (nn = (setup < 0)? 0 : 2; nn < n*2; nn += 2)
6607     {
6608     expand_nstring[expand_nmax] = subject + ovector[nn];
6609     expand_nlength[expand_nmax++] = ovector[nn+1] - ovector[nn];
6610     }
6611   expand_nmax--;
6612   }
6613 return yield;
6614 }
6615
6616
6617 int main(int argc, uschar **argv)
6618 {
6619 int i;
6620 uschar buffer[1024];
6621
6622 debug_selector = D_v;
6623 debug_file = stderr;
6624 debug_fd = fileno(debug_file);
6625 big_buffer = malloc(big_buffer_size);
6626
6627 for (i = 1; i < argc; i++)
6628   {
6629   if (argv[i][0] == '+')
6630     {
6631     debug_trace_memory = 2;
6632     argv[i]++;
6633     }
6634   if (isdigit(argv[i][0]))
6635     debug_selector = Ustrtol(argv[i], NULL, 0);
6636   else
6637     if (Ustrspn(argv[i], "abcdefghijklmnopqrtsuvwxyz0123456789-.:/") ==
6638         Ustrlen(argv[i]))
6639       {
6640       #ifdef LOOKUP_LDAP
6641       eldap_default_servers = argv[i];
6642       #endif
6643       #ifdef LOOKUP_MYSQL
6644       mysql_servers = argv[i];
6645       #endif
6646       #ifdef LOOKUP_PGSQL
6647       pgsql_servers = argv[i];
6648       #endif
6649       #ifdef EXPERIMENTAL_REDIS
6650       redis_servers = argv[i];
6651       #endif
6652       }
6653   #ifdef EXIM_PERL
6654   else opt_perl_startup = argv[i];
6655   #endif
6656   }
6657
6658 printf("Testing string expansion: debug_level = %d\n\n", debug_level);
6659
6660 expand_nstring[1] = US"string 1....";
6661 expand_nlength[1] = 8;
6662 expand_nmax = 1;
6663
6664 #ifdef EXIM_PERL
6665 if (opt_perl_startup != NULL)
6666   {
6667   uschar *errstr;
6668   printf("Starting Perl interpreter\n");
6669   errstr = init_perl(opt_perl_startup);
6670   if (errstr != NULL)
6671     {
6672     printf("** error in perl_startup code: %s\n", errstr);
6673     return EXIT_FAILURE;
6674     }
6675   }
6676 #endif /* EXIM_PERL */
6677
6678 while (fgets(buffer, sizeof(buffer), stdin) != NULL)
6679   {
6680   void *reset_point = store_get(0);
6681   uschar *yield = expand_string(buffer);
6682   if (yield != NULL)
6683     {
6684     printf("%s\n", yield);
6685     store_reset(reset_point);
6686     }
6687   else
6688     {
6689     if (search_find_defer) printf("search_find deferred\n");
6690     printf("Failed: %s\n", expand_string_message);
6691     if (expand_string_forcedfail) printf("Forced failure\n");
6692     printf("\n");
6693     }
6694   }
6695
6696 search_tidyup();
6697
6698 return 0;
6699 }
6700
6701 #endif
6702
6703 /* End of expand.c */