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Lose more string-copy operations
[exim.git] / src / src / expand.c
1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
4
5 /* Copyright (c) University of Cambridge 1995 - 2018 */
6 /* See the file NOTICE for conditions of use and distribution. */
7
8
9 /* Functions for handling string expansion. */
10
11
12 #include "exim.h"
13
14 /* Recursively called function */
15
16 static uschar *expand_string_internal(const uschar *, BOOL, const uschar **, BOOL, BOOL, BOOL *);
17 static int_eximarith_t expanded_string_integer(const uschar *, BOOL);
18
19 #ifdef STAND_ALONE
20 # ifndef SUPPORT_CRYPTEQ
21 # define SUPPORT_CRYPTEQ
22 # endif
23 #endif
24
25 #ifdef LOOKUP_LDAP
26 # include "lookups/ldap.h"
27 #endif
28
29 #ifdef SUPPORT_CRYPTEQ
30 # ifdef CRYPT_H
31 # include <crypt.h>
32 # endif
33 # ifndef HAVE_CRYPT16
34 extern char* crypt16(char*, char*);
35 # endif
36 #endif
37
38 /* The handling of crypt16() is a mess. I will record below the analysis of the
39 mess that was sent to me. We decided, however, to make changing this very low
40 priority, because in practice people are moving away from the crypt()
41 algorithms nowadays, so it doesn't seem worth it.
42
43 <quote>
44 There is an algorithm named "crypt16" in Ultrix and Tru64. It crypts
45 the first 8 characters of the password using a 20-round version of crypt
46 (standard crypt does 25 rounds). It then crypts the next 8 characters,
47 or an empty block if the password is less than 9 characters, using a
48 20-round version of crypt and the same salt as was used for the first
49 block. Characters after the first 16 are ignored. It always generates
50 a 16-byte hash, which is expressed together with the salt as a string
51 of 24 base 64 digits. Here are some links to peruse:
52
53 http://cvs.pld.org.pl/pam/pamcrypt/crypt16.c?rev=1.2
54 http://seclists.org/bugtraq/1999/Mar/0076.html
55
56 There's a different algorithm named "bigcrypt" in HP-UX, Digital Unix,
57 and OSF/1. This is the same as the standard crypt if given a password
58 of 8 characters or less. If given more, it first does the same as crypt
59 using the first 8 characters, then crypts the next 8 (the 9th to 16th)
60 using as salt the first two base 64 digits from the first hash block.
61 If the password is more than 16 characters then it crypts the 17th to 24th
62 characters using as salt the first two base 64 digits from the second hash
63 block. And so on: I've seen references to it cutting off the password at
64 40 characters (5 blocks), 80 (10 blocks), or 128 (16 blocks). Some links:
65
66 http://cvs.pld.org.pl/pam/pamcrypt/bigcrypt.c?rev=1.2
67 http://seclists.org/bugtraq/1999/Mar/0109.html
68 http://h30097.www3.hp.com/docs/base_doc/DOCUMENTATION/HTML/AA-Q0R2D-
69 TET1_html/sec.c222.html#no_id_208
70
71 Exim has something it calls "crypt16". It will either use a native
72 crypt16 or its own implementation. A native crypt16 will presumably
73 be the one that I called "crypt16" above. The internal "crypt16"
74 function, however, is a two-block-maximum implementation of what I called
75 "bigcrypt". The documentation matches the internal code.
76
77 I suspect that whoever did the "crypt16" stuff for Exim didn't realise
78 that crypt16 and bigcrypt were different things.
79
80 Exim uses the LDAP-style scheme identifier "{crypt16}" to refer
81 to whatever it is using under that name. This unfortunately sets a
82 precedent for using "{crypt16}" to identify two incompatible algorithms
83 whose output can't be distinguished. With "{crypt16}" thus rendered
84 ambiguous, I suggest you deprecate it and invent two new identifiers
85 for the two algorithms.
86
87 Both crypt16 and bigcrypt are very poor algorithms, btw. Hashing parts
88 of the password separately means they can be cracked separately, so
89 the double-length hash only doubles the cracking effort instead of
90 squaring it. I recommend salted SHA-1 ({SSHA}), or the Blowfish-based
91 bcrypt ({CRYPT}$2a$).
92 </quote>
93 */
94
95
96
97 /*************************************************
98 * Local statics and tables *
99 *************************************************/
100
101 /* Table of item names, and corresponding switch numbers. The names must be in
102 alphabetical order. */
103
104 static uschar *item_table[] = {
105 US"acl",
106 US"authresults",
107 US"certextract",
108 US"dlfunc",
109 US"env",
110 US"extract",
111 US"filter",
112 US"hash",
113 US"hmac",
114 US"if",
115 #ifdef SUPPORT_I18N
116 US"imapfolder",
117 #endif
118 US"length",
119 US"listextract",
120 US"lookup",
121 US"map",
122 US"nhash",
123 US"perl",
124 US"prvs",
125 US"prvscheck",
126 US"readfile",
127 US"readsocket",
128 US"reduce",
129 US"run",
130 US"sg",
131 US"sort",
132 US"substr",
133 US"tr" };
134
135 enum {
136 EITEM_ACL,
137 EITEM_AUTHRESULTS,
138 EITEM_CERTEXTRACT,
139 EITEM_DLFUNC,
140 EITEM_ENV,
141 EITEM_EXTRACT,
142 EITEM_FILTER,
143 EITEM_HASH,
144 EITEM_HMAC,
145 EITEM_IF,
146 #ifdef SUPPORT_I18N
147 EITEM_IMAPFOLDER,
148 #endif
149 EITEM_LENGTH,
150 EITEM_LISTEXTRACT,
151 EITEM_LOOKUP,
152 EITEM_MAP,
153 EITEM_NHASH,
154 EITEM_PERL,
155 EITEM_PRVS,
156 EITEM_PRVSCHECK,
157 EITEM_READFILE,
158 EITEM_READSOCK,
159 EITEM_REDUCE,
160 EITEM_RUN,
161 EITEM_SG,
162 EITEM_SORT,
163 EITEM_SUBSTR,
164 EITEM_TR };
165
166 /* Tables of operator names, and corresponding switch numbers. The names must be
167 in alphabetical order. There are two tables, because underscore is used in some
168 cases to introduce arguments, whereas for other it is part of the name. This is
169 an historical mis-design. */
170
171 static uschar *op_table_underscore[] = {
172 US"from_utf8",
173 US"local_part",
174 US"quote_local_part",
175 US"reverse_ip",
176 US"time_eval",
177 US"time_interval"
178 #ifdef SUPPORT_I18N
179 ,US"utf8_domain_from_alabel",
180 US"utf8_domain_to_alabel",
181 US"utf8_localpart_from_alabel",
182 US"utf8_localpart_to_alabel"
183 #endif
184 };
185
186 enum {
187 EOP_FROM_UTF8,
188 EOP_LOCAL_PART,
189 EOP_QUOTE_LOCAL_PART,
190 EOP_REVERSE_IP,
191 EOP_TIME_EVAL,
192 EOP_TIME_INTERVAL
193 #ifdef SUPPORT_I18N
194 ,EOP_UTF8_DOMAIN_FROM_ALABEL,
195 EOP_UTF8_DOMAIN_TO_ALABEL,
196 EOP_UTF8_LOCALPART_FROM_ALABEL,
197 EOP_UTF8_LOCALPART_TO_ALABEL
198 #endif
199 };
200
201 static uschar *op_table_main[] = {
202 US"address",
203 US"addresses",
204 US"base32",
205 US"base32d",
206 US"base62",
207 US"base62d",
208 US"base64",
209 US"base64d",
210 US"domain",
211 US"escape",
212 US"escape8bit",
213 US"eval",
214 US"eval10",
215 US"expand",
216 US"h",
217 US"hash",
218 US"hex2b64",
219 US"hexquote",
220 US"ipv6denorm",
221 US"ipv6norm",
222 US"l",
223 US"lc",
224 US"length",
225 US"listcount",
226 US"listnamed",
227 US"mask",
228 US"md5",
229 US"nh",
230 US"nhash",
231 US"quote",
232 US"randint",
233 US"rfc2047",
234 US"rfc2047d",
235 US"rxquote",
236 US"s",
237 US"sha1",
238 US"sha256",
239 US"sha3",
240 US"stat",
241 US"str2b64",
242 US"strlen",
243 US"substr",
244 US"uc",
245 US"utf8clean" };
246
247 enum {
248 EOP_ADDRESS = nelem(op_table_underscore),
249 EOP_ADDRESSES,
250 EOP_BASE32,
251 EOP_BASE32D,
252 EOP_BASE62,
253 EOP_BASE62D,
254 EOP_BASE64,
255 EOP_BASE64D,
256 EOP_DOMAIN,
257 EOP_ESCAPE,
258 EOP_ESCAPE8BIT,
259 EOP_EVAL,
260 EOP_EVAL10,
261 EOP_EXPAND,
262 EOP_H,
263 EOP_HASH,
264 EOP_HEX2B64,
265 EOP_HEXQUOTE,
266 EOP_IPV6DENORM,
267 EOP_IPV6NORM,
268 EOP_L,
269 EOP_LC,
270 EOP_LENGTH,
271 EOP_LISTCOUNT,
272 EOP_LISTNAMED,
273 EOP_MASK,
274 EOP_MD5,
275 EOP_NH,
276 EOP_NHASH,
277 EOP_QUOTE,
278 EOP_RANDINT,
279 EOP_RFC2047,
280 EOP_RFC2047D,
281 EOP_RXQUOTE,
282 EOP_S,
283 EOP_SHA1,
284 EOP_SHA256,
285 EOP_SHA3,
286 EOP_STAT,
287 EOP_STR2B64,
288 EOP_STRLEN,
289 EOP_SUBSTR,
290 EOP_UC,
291 EOP_UTF8CLEAN };
292
293
294 /* Table of condition names, and corresponding switch numbers. The names must
295 be in alphabetical order. */
296
297 static uschar *cond_table[] = {
298 US"<",
299 US"<=",
300 US"=",
301 US"==", /* Backward compatibility */
302 US">",
303 US">=",
304 US"acl",
305 US"and",
306 US"bool",
307 US"bool_lax",
308 US"crypteq",
309 US"def",
310 US"eq",
311 US"eqi",
312 US"exists",
313 US"first_delivery",
314 US"forall",
315 US"forany",
316 US"ge",
317 US"gei",
318 US"gt",
319 US"gti",
320 US"inlist",
321 US"inlisti",
322 US"isip",
323 US"isip4",
324 US"isip6",
325 US"ldapauth",
326 US"le",
327 US"lei",
328 US"lt",
329 US"lti",
330 US"match",
331 US"match_address",
332 US"match_domain",
333 US"match_ip",
334 US"match_local_part",
335 US"or",
336 US"pam",
337 US"pwcheck",
338 US"queue_running",
339 US"radius",
340 US"saslauthd"
341 };
342
343 enum {
344 ECOND_NUM_L,
345 ECOND_NUM_LE,
346 ECOND_NUM_E,
347 ECOND_NUM_EE,
348 ECOND_NUM_G,
349 ECOND_NUM_GE,
350 ECOND_ACL,
351 ECOND_AND,
352 ECOND_BOOL,
353 ECOND_BOOL_LAX,
354 ECOND_CRYPTEQ,
355 ECOND_DEF,
356 ECOND_STR_EQ,
357 ECOND_STR_EQI,
358 ECOND_EXISTS,
359 ECOND_FIRST_DELIVERY,
360 ECOND_FORALL,
361 ECOND_FORANY,
362 ECOND_STR_GE,
363 ECOND_STR_GEI,
364 ECOND_STR_GT,
365 ECOND_STR_GTI,
366 ECOND_INLIST,
367 ECOND_INLISTI,
368 ECOND_ISIP,
369 ECOND_ISIP4,
370 ECOND_ISIP6,
371 ECOND_LDAPAUTH,
372 ECOND_STR_LE,
373 ECOND_STR_LEI,
374 ECOND_STR_LT,
375 ECOND_STR_LTI,
376 ECOND_MATCH,
377 ECOND_MATCH_ADDRESS,
378 ECOND_MATCH_DOMAIN,
379 ECOND_MATCH_IP,
380 ECOND_MATCH_LOCAL_PART,
381 ECOND_OR,
382 ECOND_PAM,
383 ECOND_PWCHECK,
384 ECOND_QUEUE_RUNNING,
385 ECOND_RADIUS,
386 ECOND_SASLAUTHD
387 };
388
389
390 /* Types of table entry */
391
392 enum vtypes {
393 vtype_int, /* value is address of int */
394 vtype_filter_int, /* ditto, but recognized only when filtering */
395 vtype_ino, /* value is address of ino_t (not always an int) */
396 vtype_uid, /* value is address of uid_t (not always an int) */
397 vtype_gid, /* value is address of gid_t (not always an int) */
398 vtype_bool, /* value is address of bool */
399 vtype_stringptr, /* value is address of pointer to string */
400 vtype_msgbody, /* as stringptr, but read when first required */
401 vtype_msgbody_end, /* ditto, the end of the message */
402 vtype_msgheaders, /* the message's headers, processed */
403 vtype_msgheaders_raw, /* the message's headers, unprocessed */
404 vtype_localpart, /* extract local part from string */
405 vtype_domain, /* extract domain from string */
406 vtype_string_func, /* value is string returned by given function */
407 vtype_todbsdin, /* value not used; generate BSD inbox tod */
408 vtype_tode, /* value not used; generate tod in epoch format */
409 vtype_todel, /* value not used; generate tod in epoch/usec format */
410 vtype_todf, /* value not used; generate full tod */
411 vtype_todl, /* value not used; generate log tod */
412 vtype_todlf, /* value not used; generate log file datestamp tod */
413 vtype_todzone, /* value not used; generate time zone only */
414 vtype_todzulu, /* value not used; generate zulu tod */
415 vtype_reply, /* value not used; get reply from headers */
416 vtype_pid, /* value not used; result is pid */
417 vtype_host_lookup, /* value not used; get host name */
418 vtype_load_avg, /* value not used; result is int from os_getloadavg */
419 vtype_pspace, /* partition space; value is T/F for spool/log */
420 vtype_pinodes, /* partition inodes; value is T/F for spool/log */
421 vtype_cert /* SSL certificate */
422 #ifndef DISABLE_DKIM
423 ,vtype_dkim /* Lookup of value in DKIM signature */
424 #endif
425 };
426
427 /* Type for main variable table */
428
429 typedef struct {
430 const char *name;
431 enum vtypes type;
432 void *value;
433 } var_entry;
434
435 /* Type for entries pointing to address/length pairs. Not currently
436 in use. */
437
438 typedef struct {
439 uschar **address;
440 int *length;
441 } alblock;
442
443 static uschar * fn_recipients(void);
444
445 /* This table must be kept in alphabetical order. */
446
447 static var_entry var_table[] = {
448 /* WARNING: Do not invent variables whose names start acl_c or acl_m because
449 they will be confused with user-creatable ACL variables. */
450 { "acl_arg1", vtype_stringptr, &acl_arg[0] },
451 { "acl_arg2", vtype_stringptr, &acl_arg[1] },
452 { "acl_arg3", vtype_stringptr, &acl_arg[2] },
453 { "acl_arg4", vtype_stringptr, &acl_arg[3] },
454 { "acl_arg5", vtype_stringptr, &acl_arg[4] },
455 { "acl_arg6", vtype_stringptr, &acl_arg[5] },
456 { "acl_arg7", vtype_stringptr, &acl_arg[6] },
457 { "acl_arg8", vtype_stringptr, &acl_arg[7] },
458 { "acl_arg9", vtype_stringptr, &acl_arg[8] },
459 { "acl_narg", vtype_int, &acl_narg },
460 { "acl_verify_message", vtype_stringptr, &acl_verify_message },
461 { "address_data", vtype_stringptr, &deliver_address_data },
462 { "address_file", vtype_stringptr, &address_file },
463 { "address_pipe", vtype_stringptr, &address_pipe },
464 #ifdef EXPERIMENTAL_ARC
465 { "arc_domains", vtype_string_func, &fn_arc_domains },
466 { "arc_oldest_pass", vtype_int, &arc_oldest_pass },
467 { "arc_state", vtype_stringptr, &arc_state },
468 { "arc_state_reason", vtype_stringptr, &arc_state_reason },
469 #endif
470 { "authenticated_fail_id",vtype_stringptr, &authenticated_fail_id },
471 { "authenticated_id", vtype_stringptr, &authenticated_id },
472 { "authenticated_sender",vtype_stringptr, &authenticated_sender },
473 { "authentication_failed",vtype_int, &authentication_failed },
474 #ifdef WITH_CONTENT_SCAN
475 { "av_failed", vtype_int, &av_failed },
476 #endif
477 #ifdef EXPERIMENTAL_BRIGHTMAIL
478 { "bmi_alt_location", vtype_stringptr, &bmi_alt_location },
479 { "bmi_base64_tracker_verdict", vtype_stringptr, &bmi_base64_tracker_verdict },
480 { "bmi_base64_verdict", vtype_stringptr, &bmi_base64_verdict },
481 { "bmi_deliver", vtype_int, &bmi_deliver },
482 #endif
483 { "body_linecount", vtype_int, &body_linecount },
484 { "body_zerocount", vtype_int, &body_zerocount },
485 { "bounce_recipient", vtype_stringptr, &bounce_recipient },
486 { "bounce_return_size_limit", vtype_int, &bounce_return_size_limit },
487 { "caller_gid", vtype_gid, &real_gid },
488 { "caller_uid", vtype_uid, &real_uid },
489 { "callout_address", vtype_stringptr, &callout_address },
490 { "compile_date", vtype_stringptr, &version_date },
491 { "compile_number", vtype_stringptr, &version_cnumber },
492 { "config_dir", vtype_stringptr, &config_main_directory },
493 { "config_file", vtype_stringptr, &config_main_filename },
494 { "csa_status", vtype_stringptr, &csa_status },
495 #ifdef EXPERIMENTAL_DCC
496 { "dcc_header", vtype_stringptr, &dcc_header },
497 { "dcc_result", vtype_stringptr, &dcc_result },
498 #endif
499 #ifndef DISABLE_DKIM
500 { "dkim_algo", vtype_dkim, (void *)DKIM_ALGO },
501 { "dkim_bodylength", vtype_dkim, (void *)DKIM_BODYLENGTH },
502 { "dkim_canon_body", vtype_dkim, (void *)DKIM_CANON_BODY },
503 { "dkim_canon_headers", vtype_dkim, (void *)DKIM_CANON_HEADERS },
504 { "dkim_copiedheaders", vtype_dkim, (void *)DKIM_COPIEDHEADERS },
505 { "dkim_created", vtype_dkim, (void *)DKIM_CREATED },
506 { "dkim_cur_signer", vtype_stringptr, &dkim_cur_signer },
507 { "dkim_domain", vtype_stringptr, &dkim_signing_domain },
508 { "dkim_expires", vtype_dkim, (void *)DKIM_EXPIRES },
509 { "dkim_headernames", vtype_dkim, (void *)DKIM_HEADERNAMES },
510 { "dkim_identity", vtype_dkim, (void *)DKIM_IDENTITY },
511 { "dkim_key_granularity",vtype_dkim, (void *)DKIM_KEY_GRANULARITY },
512 { "dkim_key_length", vtype_int, &dkim_key_length },
513 { "dkim_key_nosubdomains",vtype_dkim, (void *)DKIM_NOSUBDOMAINS },
514 { "dkim_key_notes", vtype_dkim, (void *)DKIM_KEY_NOTES },
515 { "dkim_key_srvtype", vtype_dkim, (void *)DKIM_KEY_SRVTYPE },
516 { "dkim_key_testing", vtype_dkim, (void *)DKIM_KEY_TESTING },
517 { "dkim_selector", vtype_stringptr, &dkim_signing_selector },
518 { "dkim_signers", vtype_stringptr, &dkim_signers },
519 { "dkim_verify_reason", vtype_stringptr, &dkim_verify_reason },
520 { "dkim_verify_status", vtype_stringptr, &dkim_verify_status },
521 #endif
522 #ifdef EXPERIMENTAL_DMARC
523 { "dmarc_domain_policy", vtype_stringptr, &dmarc_domain_policy },
524 { "dmarc_status", vtype_stringptr, &dmarc_status },
525 { "dmarc_status_text", vtype_stringptr, &dmarc_status_text },
526 { "dmarc_used_domain", vtype_stringptr, &dmarc_used_domain },
527 #endif
528 { "dnslist_domain", vtype_stringptr, &dnslist_domain },
529 { "dnslist_matched", vtype_stringptr, &dnslist_matched },
530 { "dnslist_text", vtype_stringptr, &dnslist_text },
531 { "dnslist_value", vtype_stringptr, &dnslist_value },
532 { "domain", vtype_stringptr, &deliver_domain },
533 { "domain_data", vtype_stringptr, &deliver_domain_data },
534 #ifndef DISABLE_EVENT
535 { "event_data", vtype_stringptr, &event_data },
536
537 /*XXX want to use generic vars for as many of these as possible*/
538 { "event_defer_errno", vtype_int, &event_defer_errno },
539
540 { "event_name", vtype_stringptr, &event_name },
541 #endif
542 { "exim_gid", vtype_gid, &exim_gid },
543 { "exim_path", vtype_stringptr, &exim_path },
544 { "exim_uid", vtype_uid, &exim_uid },
545 { "exim_version", vtype_stringptr, &version_string },
546 { "headers_added", vtype_string_func, &fn_hdrs_added },
547 { "home", vtype_stringptr, &deliver_home },
548 { "host", vtype_stringptr, &deliver_host },
549 { "host_address", vtype_stringptr, &deliver_host_address },
550 { "host_data", vtype_stringptr, &host_data },
551 { "host_lookup_deferred",vtype_int, &host_lookup_deferred },
552 { "host_lookup_failed", vtype_int, &host_lookup_failed },
553 { "host_port", vtype_int, &deliver_host_port },
554 { "initial_cwd", vtype_stringptr, &initial_cwd },
555 { "inode", vtype_ino, &deliver_inode },
556 { "interface_address", vtype_stringptr, &interface_address },
557 { "interface_port", vtype_int, &interface_port },
558 { "item", vtype_stringptr, &iterate_item },
559 #ifdef LOOKUP_LDAP
560 { "ldap_dn", vtype_stringptr, &eldap_dn },
561 #endif
562 { "load_average", vtype_load_avg, NULL },
563 { "local_part", vtype_stringptr, &deliver_localpart },
564 { "local_part_data", vtype_stringptr, &deliver_localpart_data },
565 { "local_part_prefix", vtype_stringptr, &deliver_localpart_prefix },
566 { "local_part_suffix", vtype_stringptr, &deliver_localpart_suffix },
567 #ifdef HAVE_LOCAL_SCAN
568 { "local_scan_data", vtype_stringptr, &local_scan_data },
569 #endif
570 { "local_user_gid", vtype_gid, &local_user_gid },
571 { "local_user_uid", vtype_uid, &local_user_uid },
572 { "localhost_number", vtype_int, &host_number },
573 { "log_inodes", vtype_pinodes, (void *)FALSE },
574 { "log_space", vtype_pspace, (void *)FALSE },
575 { "lookup_dnssec_authenticated",vtype_stringptr,&lookup_dnssec_authenticated},
576 { "mailstore_basename", vtype_stringptr, &mailstore_basename },
577 #ifdef WITH_CONTENT_SCAN
578 { "malware_name", vtype_stringptr, &malware_name },
579 #endif
580 { "max_received_linelength", vtype_int, &max_received_linelength },
581 { "message_age", vtype_int, &message_age },
582 { "message_body", vtype_msgbody, &message_body },
583 { "message_body_end", vtype_msgbody_end, &message_body_end },
584 { "message_body_size", vtype_int, &message_body_size },
585 { "message_exim_id", vtype_stringptr, &message_id },
586 { "message_headers", vtype_msgheaders, NULL },
587 { "message_headers_raw", vtype_msgheaders_raw, NULL },
588 { "message_id", vtype_stringptr, &message_id },
589 { "message_linecount", vtype_int, &message_linecount },
590 { "message_size", vtype_int, &message_size },
591 #ifdef SUPPORT_I18N
592 { "message_smtputf8", vtype_bool, &message_smtputf8 },
593 #endif
594 #ifdef WITH_CONTENT_SCAN
595 { "mime_anomaly_level", vtype_int, &mime_anomaly_level },
596 { "mime_anomaly_text", vtype_stringptr, &mime_anomaly_text },
597 { "mime_boundary", vtype_stringptr, &mime_boundary },
598 { "mime_charset", vtype_stringptr, &mime_charset },
599 { "mime_content_description", vtype_stringptr, &mime_content_description },
600 { "mime_content_disposition", vtype_stringptr, &mime_content_disposition },
601 { "mime_content_id", vtype_stringptr, &mime_content_id },
602 { "mime_content_size", vtype_int, &mime_content_size },
603 { "mime_content_transfer_encoding",vtype_stringptr, &mime_content_transfer_encoding },
604 { "mime_content_type", vtype_stringptr, &mime_content_type },
605 { "mime_decoded_filename", vtype_stringptr, &mime_decoded_filename },
606 { "mime_filename", vtype_stringptr, &mime_filename },
607 { "mime_is_coverletter", vtype_int, &mime_is_coverletter },
608 { "mime_is_multipart", vtype_int, &mime_is_multipart },
609 { "mime_is_rfc822", vtype_int, &mime_is_rfc822 },
610 { "mime_part_count", vtype_int, &mime_part_count },
611 #endif
612 { "n0", vtype_filter_int, &filter_n[0] },
613 { "n1", vtype_filter_int, &filter_n[1] },
614 { "n2", vtype_filter_int, &filter_n[2] },
615 { "n3", vtype_filter_int, &filter_n[3] },
616 { "n4", vtype_filter_int, &filter_n[4] },
617 { "n5", vtype_filter_int, &filter_n[5] },
618 { "n6", vtype_filter_int, &filter_n[6] },
619 { "n7", vtype_filter_int, &filter_n[7] },
620 { "n8", vtype_filter_int, &filter_n[8] },
621 { "n9", vtype_filter_int, &filter_n[9] },
622 { "original_domain", vtype_stringptr, &deliver_domain_orig },
623 { "original_local_part", vtype_stringptr, &deliver_localpart_orig },
624 { "originator_gid", vtype_gid, &originator_gid },
625 { "originator_uid", vtype_uid, &originator_uid },
626 { "parent_domain", vtype_stringptr, &deliver_domain_parent },
627 { "parent_local_part", vtype_stringptr, &deliver_localpart_parent },
628 { "pid", vtype_pid, NULL },
629 #ifndef DISABLE_PRDR
630 { "prdr_requested", vtype_bool, &prdr_requested },
631 #endif
632 { "primary_hostname", vtype_stringptr, &primary_hostname },
633 #if defined(SUPPORT_PROXY) || defined(SUPPORT_SOCKS)
634 { "proxy_external_address",vtype_stringptr, &proxy_external_address },
635 { "proxy_external_port", vtype_int, &proxy_external_port },
636 { "proxy_local_address", vtype_stringptr, &proxy_local_address },
637 { "proxy_local_port", vtype_int, &proxy_local_port },
638 { "proxy_session", vtype_bool, &proxy_session },
639 #endif
640 { "prvscheck_address", vtype_stringptr, &prvscheck_address },
641 { "prvscheck_keynum", vtype_stringptr, &prvscheck_keynum },
642 { "prvscheck_result", vtype_stringptr, &prvscheck_result },
643 { "qualify_domain", vtype_stringptr, &qualify_domain_sender },
644 { "qualify_recipient", vtype_stringptr, &qualify_domain_recipient },
645 { "queue_name", vtype_stringptr, &queue_name },
646 { "rcpt_count", vtype_int, &rcpt_count },
647 { "rcpt_defer_count", vtype_int, &rcpt_defer_count },
648 { "rcpt_fail_count", vtype_int, &rcpt_fail_count },
649 { "received_count", vtype_int, &received_count },
650 { "received_for", vtype_stringptr, &received_for },
651 { "received_ip_address", vtype_stringptr, &interface_address },
652 { "received_port", vtype_int, &interface_port },
653 { "received_protocol", vtype_stringptr, &received_protocol },
654 { "received_time", vtype_int, &received_time.tv_sec },
655 { "recipient_data", vtype_stringptr, &recipient_data },
656 { "recipient_verify_failure",vtype_stringptr,&recipient_verify_failure },
657 { "recipients", vtype_string_func, &fn_recipients },
658 { "recipients_count", vtype_int, &recipients_count },
659 #ifdef WITH_CONTENT_SCAN
660 { "regex_match_string", vtype_stringptr, &regex_match_string },
661 #endif
662 { "reply_address", vtype_reply, NULL },
663 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_REQUIRETLS)
664 { "requiretls", vtype_bool, &tls_requiretls },
665 #endif
666 { "return_path", vtype_stringptr, &return_path },
667 { "return_size_limit", vtype_int, &bounce_return_size_limit },
668 { "router_name", vtype_stringptr, &router_name },
669 { "runrc", vtype_int, &runrc },
670 { "self_hostname", vtype_stringptr, &self_hostname },
671 { "sender_address", vtype_stringptr, &sender_address },
672 { "sender_address_data", vtype_stringptr, &sender_address_data },
673 { "sender_address_domain", vtype_domain, &sender_address },
674 { "sender_address_local_part", vtype_localpart, &sender_address },
675 { "sender_data", vtype_stringptr, &sender_data },
676 { "sender_fullhost", vtype_stringptr, &sender_fullhost },
677 { "sender_helo_dnssec", vtype_bool, &sender_helo_dnssec },
678 { "sender_helo_name", vtype_stringptr, &sender_helo_name },
679 { "sender_host_address", vtype_stringptr, &sender_host_address },
680 { "sender_host_authenticated",vtype_stringptr, &sender_host_authenticated },
681 { "sender_host_dnssec", vtype_bool, &sender_host_dnssec },
682 { "sender_host_name", vtype_host_lookup, NULL },
683 { "sender_host_port", vtype_int, &sender_host_port },
684 { "sender_ident", vtype_stringptr, &sender_ident },
685 { "sender_rate", vtype_stringptr, &sender_rate },
686 { "sender_rate_limit", vtype_stringptr, &sender_rate_limit },
687 { "sender_rate_period", vtype_stringptr, &sender_rate_period },
688 { "sender_rcvhost", vtype_stringptr, &sender_rcvhost },
689 { "sender_verify_failure",vtype_stringptr, &sender_verify_failure },
690 { "sending_ip_address", vtype_stringptr, &sending_ip_address },
691 { "sending_port", vtype_int, &sending_port },
692 { "smtp_active_hostname", vtype_stringptr, &smtp_active_hostname },
693 { "smtp_command", vtype_stringptr, &smtp_cmd_buffer },
694 { "smtp_command_argument", vtype_stringptr, &smtp_cmd_argument },
695 { "smtp_command_history", vtype_string_func, &smtp_cmd_hist },
696 { "smtp_count_at_connection_start", vtype_int, &smtp_accept_count },
697 { "smtp_notquit_reason", vtype_stringptr, &smtp_notquit_reason },
698 { "sn0", vtype_filter_int, &filter_sn[0] },
699 { "sn1", vtype_filter_int, &filter_sn[1] },
700 { "sn2", vtype_filter_int, &filter_sn[2] },
701 { "sn3", vtype_filter_int, &filter_sn[3] },
702 { "sn4", vtype_filter_int, &filter_sn[4] },
703 { "sn5", vtype_filter_int, &filter_sn[5] },
704 { "sn6", vtype_filter_int, &filter_sn[6] },
705 { "sn7", vtype_filter_int, &filter_sn[7] },
706 { "sn8", vtype_filter_int, &filter_sn[8] },
707 { "sn9", vtype_filter_int, &filter_sn[9] },
708 #ifdef WITH_CONTENT_SCAN
709 { "spam_action", vtype_stringptr, &spam_action },
710 { "spam_bar", vtype_stringptr, &spam_bar },
711 { "spam_report", vtype_stringptr, &spam_report },
712 { "spam_score", vtype_stringptr, &spam_score },
713 { "spam_score_int", vtype_stringptr, &spam_score_int },
714 #endif
715 #ifdef SUPPORT_SPF
716 { "spf_guess", vtype_stringptr, &spf_guess },
717 { "spf_header_comment", vtype_stringptr, &spf_header_comment },
718 { "spf_received", vtype_stringptr, &spf_received },
719 { "spf_result", vtype_stringptr, &spf_result },
720 { "spf_result_guessed", vtype_bool, &spf_result_guessed },
721 { "spf_smtp_comment", vtype_stringptr, &spf_smtp_comment },
722 #endif
723 { "spool_directory", vtype_stringptr, &spool_directory },
724 { "spool_inodes", vtype_pinodes, (void *)TRUE },
725 { "spool_space", vtype_pspace, (void *)TRUE },
726 #ifdef EXPERIMENTAL_SRS
727 { "srs_db_address", vtype_stringptr, &srs_db_address },
728 { "srs_db_key", vtype_stringptr, &srs_db_key },
729 { "srs_orig_recipient", vtype_stringptr, &srs_orig_recipient },
730 { "srs_orig_sender", vtype_stringptr, &srs_orig_sender },
731 { "srs_recipient", vtype_stringptr, &srs_recipient },
732 { "srs_status", vtype_stringptr, &srs_status },
733 #endif
734 { "thisaddress", vtype_stringptr, &filter_thisaddress },
735
736 /* The non-(in,out) variables are now deprecated */
737 { "tls_bits", vtype_int, &tls_in.bits },
738 { "tls_certificate_verified", vtype_int, &tls_in.certificate_verified },
739 { "tls_cipher", vtype_stringptr, &tls_in.cipher },
740
741 { "tls_in_bits", vtype_int, &tls_in.bits },
742 { "tls_in_certificate_verified", vtype_int, &tls_in.certificate_verified },
743 { "tls_in_cipher", vtype_stringptr, &tls_in.cipher },
744 { "tls_in_ocsp", vtype_int, &tls_in.ocsp },
745 { "tls_in_ourcert", vtype_cert, &tls_in.ourcert },
746 { "tls_in_peercert", vtype_cert, &tls_in.peercert },
747 { "tls_in_peerdn", vtype_stringptr, &tls_in.peerdn },
748 #if defined(SUPPORT_TLS)
749 { "tls_in_sni", vtype_stringptr, &tls_in.sni },
750 #endif
751 { "tls_out_bits", vtype_int, &tls_out.bits },
752 { "tls_out_certificate_verified", vtype_int,&tls_out.certificate_verified },
753 { "tls_out_cipher", vtype_stringptr, &tls_out.cipher },
754 #ifdef SUPPORT_DANE
755 { "tls_out_dane", vtype_bool, &tls_out.dane_verified },
756 #endif
757 { "tls_out_ocsp", vtype_int, &tls_out.ocsp },
758 { "tls_out_ourcert", vtype_cert, &tls_out.ourcert },
759 { "tls_out_peercert", vtype_cert, &tls_out.peercert },
760 { "tls_out_peerdn", vtype_stringptr, &tls_out.peerdn },
761 #if defined(SUPPORT_TLS)
762 { "tls_out_sni", vtype_stringptr, &tls_out.sni },
763 #endif
764 #ifdef SUPPORT_DANE
765 { "tls_out_tlsa_usage", vtype_int, &tls_out.tlsa_usage },
766 #endif
767
768 { "tls_peerdn", vtype_stringptr, &tls_in.peerdn }, /* mind the alphabetical order! */
769 #if defined(SUPPORT_TLS)
770 { "tls_sni", vtype_stringptr, &tls_in.sni }, /* mind the alphabetical order! */
771 #endif
772
773 { "tod_bsdinbox", vtype_todbsdin, NULL },
774 { "tod_epoch", vtype_tode, NULL },
775 { "tod_epoch_l", vtype_todel, NULL },
776 { "tod_full", vtype_todf, NULL },
777 { "tod_log", vtype_todl, NULL },
778 { "tod_logfile", vtype_todlf, NULL },
779 { "tod_zone", vtype_todzone, NULL },
780 { "tod_zulu", vtype_todzulu, NULL },
781 { "transport_name", vtype_stringptr, &transport_name },
782 { "value", vtype_stringptr, &lookup_value },
783 { "verify_mode", vtype_stringptr, &verify_mode },
784 { "version_number", vtype_stringptr, &version_string },
785 { "warn_message_delay", vtype_stringptr, &warnmsg_delay },
786 { "warn_message_recipient",vtype_stringptr, &warnmsg_recipients },
787 { "warn_message_recipients",vtype_stringptr,&warnmsg_recipients },
788 { "warnmsg_delay", vtype_stringptr, &warnmsg_delay },
789 { "warnmsg_recipient", vtype_stringptr, &warnmsg_recipients },
790 { "warnmsg_recipients", vtype_stringptr, &warnmsg_recipients }
791 };
792
793 static int var_table_size = nelem(var_table);
794 static uschar var_buffer[256];
795 static BOOL malformed_header;
796
797 /* For textual hashes */
798
799 static const char *hashcodes = "abcdefghijklmnopqrtsuvwxyz"
800 "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
801 "0123456789";
802
803 enum { HMAC_MD5, HMAC_SHA1 };
804
805 /* For numeric hashes */
806
807 static unsigned int prime[] = {
808 2, 3, 5, 7, 11, 13, 17, 19, 23, 29,
809 31, 37, 41, 43, 47, 53, 59, 61, 67, 71,
810 73, 79, 83, 89, 97, 101, 103, 107, 109, 113};
811
812 /* For printing modes in symbolic form */
813
814 static uschar *mtable_normal[] =
815 { US"---", US"--x", US"-w-", US"-wx", US"r--", US"r-x", US"rw-", US"rwx" };
816
817 static uschar *mtable_setid[] =
818 { US"--S", US"--s", US"-wS", US"-ws", US"r-S", US"r-s", US"rwS", US"rws" };
819
820 static uschar *mtable_sticky[] =
821 { US"--T", US"--t", US"-wT", US"-wt", US"r-T", US"r-t", US"rwT", US"rwt" };
822
823 /* flags for find_header() */
824 #define FH_EXISTS_ONLY BIT(0)
825 #define FH_WANT_RAW BIT(1)
826 #define FH_WANT_LIST BIT(2)
827
828
829 /*************************************************
830 * Tables for UTF-8 support *
831 *************************************************/
832
833 /* Table of the number of extra characters, indexed by the first character
834 masked with 0x3f. The highest number for a valid UTF-8 character is in fact
835 0x3d. */
836
837 static uschar utf8_table1[] = {
838 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
839 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
840 2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
841 3,3,3,3,3,3,3,3,4,4,4,4,5,5,5,5 };
842
843 /* These are the masks for the data bits in the first byte of a character,
844 indexed by the number of additional bytes. */
845
846 static int utf8_table2[] = { 0xff, 0x1f, 0x0f, 0x07, 0x03, 0x01};
847
848 /* Get the next UTF-8 character, advancing the pointer. */
849
850 #define GETUTF8INC(c, ptr) \
851 c = *ptr++; \
852 if ((c & 0xc0) == 0xc0) \
853 { \
854 int a = utf8_table1[c & 0x3f]; /* Number of additional bytes */ \
855 int s = 6*a; \
856 c = (c & utf8_table2[a]) << s; \
857 while (a-- > 0) \
858 { \
859 s -= 6; \
860 c |= (*ptr++ & 0x3f) << s; \
861 } \
862 }
863
864
865
866 static uschar * base32_chars = US"abcdefghijklmnopqrstuvwxyz234567";
867
868 /*************************************************
869 * Binary chop search on a table *
870 *************************************************/
871
872 /* This is used for matching expansion items and operators.
873
874 Arguments:
875 name the name that is being sought
876 table the table to search
877 table_size the number of items in the table
878
879 Returns: the offset in the table, or -1
880 */
881
882 static int
883 chop_match(uschar *name, uschar **table, int table_size)
884 {
885 uschar **bot = table;
886 uschar **top = table + table_size;
887
888 while (top > bot)
889 {
890 uschar **mid = bot + (top - bot)/2;
891 int c = Ustrcmp(name, *mid);
892 if (c == 0) return mid - table;
893 if (c > 0) bot = mid + 1; else top = mid;
894 }
895
896 return -1;
897 }
898
899
900
901 /*************************************************
902 * Check a condition string *
903 *************************************************/
904
905 /* This function is called to expand a string, and test the result for a "true"
906 or "false" value. Failure of the expansion yields FALSE; logged unless it was a
907 forced fail or lookup defer.
908
909 We used to release all store used, but this is not not safe due
910 to ${dlfunc } and ${acl }. In any case expand_string_internal()
911 is reasonably careful to release what it can.
912
913 The actual false-value tests should be replicated for ECOND_BOOL_LAX.
914
915 Arguments:
916 condition the condition string
917 m1 text to be incorporated in panic error
918 m2 ditto
919
920 Returns: TRUE if condition is met, FALSE if not
921 */
922
923 BOOL
924 expand_check_condition(uschar *condition, uschar *m1, uschar *m2)
925 {
926 int rc;
927 uschar *ss = expand_string(condition);
928 if (ss == NULL)
929 {
930 if (!f.expand_string_forcedfail && !f.search_find_defer)
931 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand condition \"%s\" "
932 "for %s %s: %s", condition, m1, m2, expand_string_message);
933 return FALSE;
934 }
935 rc = ss[0] != 0 && Ustrcmp(ss, "0") != 0 && strcmpic(ss, US"no") != 0 &&
936 strcmpic(ss, US"false") != 0;
937 return rc;
938 }
939
940
941
942
943 /*************************************************
944 * Pseudo-random number generation *
945 *************************************************/
946
947 /* Pseudo-random number generation. The result is not "expected" to be
948 cryptographically strong but not so weak that someone will shoot themselves
949 in the foot using it as a nonce in some email header scheme or whatever
950 weirdness they'll twist this into. The result should ideally handle fork().
951
952 However, if we're stuck unable to provide this, then we'll fall back to
953 appallingly bad randomness.
954
955 If SUPPORT_TLS is defined then this will not be used except as an emergency
956 fallback.
957
958 Arguments:
959 max range maximum
960 Returns a random number in range [0, max-1]
961 */
962
963 #ifdef SUPPORT_TLS
964 # define vaguely_random_number vaguely_random_number_fallback
965 #endif
966 int
967 vaguely_random_number(int max)
968 {
969 #ifdef SUPPORT_TLS
970 # undef vaguely_random_number
971 #endif
972 static pid_t pid = 0;
973 pid_t p2;
974 #if defined(HAVE_SRANDOM) && !defined(HAVE_SRANDOMDEV)
975 struct timeval tv;
976 #endif
977
978 p2 = getpid();
979 if (p2 != pid)
980 {
981 if (pid != 0)
982 {
983
984 #ifdef HAVE_ARC4RANDOM
985 /* cryptographically strong randomness, common on *BSD platforms, not
986 so much elsewhere. Alas. */
987 #ifndef NOT_HAVE_ARC4RANDOM_STIR
988 arc4random_stir();
989 #endif
990 #elif defined(HAVE_SRANDOM) || defined(HAVE_SRANDOMDEV)
991 #ifdef HAVE_SRANDOMDEV
992 /* uses random(4) for seeding */
993 srandomdev();
994 #else
995 gettimeofday(&tv, NULL);
996 srandom(tv.tv_sec | tv.tv_usec | getpid());
997 #endif
998 #else
999 /* Poor randomness and no seeding here */
1000 #endif
1001
1002 }
1003 pid = p2;
1004 }
1005
1006 #ifdef HAVE_ARC4RANDOM
1007 return arc4random() % max;
1008 #elif defined(HAVE_SRANDOM) || defined(HAVE_SRANDOMDEV)
1009 return random() % max;
1010 #else
1011 /* This one returns a 16-bit number, definitely not crypto-strong */
1012 return random_number(max);
1013 #endif
1014 }
1015
1016
1017
1018
1019 /*************************************************
1020 * Pick out a name from a string *
1021 *************************************************/
1022
1023 /* If the name is too long, it is silently truncated.
1024
1025 Arguments:
1026 name points to a buffer into which to put the name
1027 max is the length of the buffer
1028 s points to the first alphabetic character of the name
1029 extras chars other than alphanumerics to permit
1030
1031 Returns: pointer to the first character after the name
1032
1033 Note: The test for *s != 0 in the while loop is necessary because
1034 Ustrchr() yields non-NULL if the character is zero (which is not something
1035 I expected). */
1036
1037 static const uschar *
1038 read_name(uschar *name, int max, const uschar *s, uschar *extras)
1039 {
1040 int ptr = 0;
1041 while (*s != 0 && (isalnum(*s) || Ustrchr(extras, *s) != NULL))
1042 {
1043 if (ptr < max-1) name[ptr++] = *s;
1044 s++;
1045 }
1046 name[ptr] = 0;
1047 return s;
1048 }
1049
1050
1051
1052 /*************************************************
1053 * Pick out the rest of a header name *
1054 *************************************************/
1055
1056 /* A variable name starting $header_ (or just $h_ for those who like
1057 abbreviations) might not be the complete header name because headers can
1058 contain any printing characters in their names, except ':'. This function is
1059 called to read the rest of the name, chop h[eader]_ off the front, and put ':'
1060 on the end, if the name was terminated by white space.
1061
1062 Arguments:
1063 name points to a buffer in which the name read so far exists
1064 max is the length of the buffer
1065 s points to the first character after the name so far, i.e. the
1066 first non-alphameric character after $header_xxxxx
1067
1068 Returns: a pointer to the first character after the header name
1069 */
1070
1071 static const uschar *
1072 read_header_name(uschar *name, int max, const uschar *s)
1073 {
1074 int prelen = Ustrchr(name, '_') - name + 1;
1075 int ptr = Ustrlen(name) - prelen;
1076 if (ptr > 0) memmove(name, name+prelen, ptr);
1077 while (mac_isgraph(*s) && *s != ':')
1078 {
1079 if (ptr < max-1) name[ptr++] = *s;
1080 s++;
1081 }
1082 if (*s == ':') s++;
1083 name[ptr++] = ':';
1084 name[ptr] = 0;
1085 return s;
1086 }
1087
1088
1089
1090 /*************************************************
1091 * Pick out a number from a string *
1092 *************************************************/
1093
1094 /* Arguments:
1095 n points to an integer into which to put the number
1096 s points to the first digit of the number
1097
1098 Returns: a pointer to the character after the last digit
1099 */
1100 /*XXX consider expanding to int_eximarith_t. But the test for
1101 "overbig numbers" in 0002 still needs to overflow it. */
1102
1103 static uschar *
1104 read_number(int *n, uschar *s)
1105 {
1106 *n = 0;
1107 while (isdigit(*s)) *n = *n * 10 + (*s++ - '0');
1108 return s;
1109 }
1110
1111 static const uschar *
1112 read_cnumber(int *n, const uschar *s)
1113 {
1114 *n = 0;
1115 while (isdigit(*s)) *n = *n * 10 + (*s++ - '0');
1116 return s;
1117 }
1118
1119
1120
1121 /*************************************************
1122 * Extract keyed subfield from a string *
1123 *************************************************/
1124
1125 /* The yield is in dynamic store; NULL means that the key was not found.
1126
1127 Arguments:
1128 key points to the name of the key
1129 s points to the string from which to extract the subfield
1130
1131 Returns: NULL if the subfield was not found, or
1132 a pointer to the subfield's data
1133 */
1134
1135 static uschar *
1136 expand_getkeyed(uschar * key, const uschar * s)
1137 {
1138 int length = Ustrlen(key);
1139 while (isspace(*s)) s++;
1140
1141 /* Loop to search for the key */
1142
1143 while (*s)
1144 {
1145 int dkeylength;
1146 uschar * data;
1147 const uschar * dkey = s;
1148
1149 while (*s && *s != '=' && !isspace(*s)) s++;
1150 dkeylength = s - dkey;
1151 while (isspace(*s)) s++;
1152 if (*s == '=') while (isspace((*(++s))));
1153
1154 data = string_dequote(&s);
1155 if (length == dkeylength && strncmpic(key, dkey, length) == 0)
1156 return data;
1157
1158 while (isspace(*s)) s++;
1159 }
1160
1161 return NULL;
1162 }
1163
1164
1165
1166 static var_entry *
1167 find_var_ent(uschar * name)
1168 {
1169 int first = 0;
1170 int last = var_table_size;
1171
1172 while (last > first)
1173 {
1174 int middle = (first + last)/2;
1175 int c = Ustrcmp(name, var_table[middle].name);
1176
1177 if (c > 0) { first = middle + 1; continue; }
1178 if (c < 0) { last = middle; continue; }
1179 return &var_table[middle];
1180 }
1181 return NULL;
1182 }
1183
1184 /*************************************************
1185 * Extract numbered subfield from string *
1186 *************************************************/
1187
1188 /* Extracts a numbered field from a string that is divided by tokens - for
1189 example a line from /etc/passwd is divided by colon characters. First field is
1190 numbered one. Negative arguments count from the right. Zero returns the whole
1191 string. Returns NULL if there are insufficient tokens in the string
1192
1193 ***WARNING***
1194 Modifies final argument - this is a dynamically generated string, so that's OK.
1195
1196 Arguments:
1197 field number of field to be extracted,
1198 first field = 1, whole string = 0, last field = -1
1199 separators characters that are used to break string into tokens
1200 s points to the string from which to extract the subfield
1201
1202 Returns: NULL if the field was not found,
1203 a pointer to the field's data inside s (modified to add 0)
1204 */
1205
1206 static uschar *
1207 expand_gettokened (int field, uschar *separators, uschar *s)
1208 {
1209 int sep = 1;
1210 int count;
1211 uschar *ss = s;
1212 uschar *fieldtext = NULL;
1213
1214 if (field == 0) return s;
1215
1216 /* Break the line up into fields in place; for field > 0 we stop when we have
1217 done the number of fields we want. For field < 0 we continue till the end of
1218 the string, counting the number of fields. */
1219
1220 count = (field > 0)? field : INT_MAX;
1221
1222 while (count-- > 0)
1223 {
1224 size_t len;
1225
1226 /* Previous field was the last one in the string. For a positive field
1227 number, this means there are not enough fields. For a negative field number,
1228 check that there are enough, and scan back to find the one that is wanted. */
1229
1230 if (sep == 0)
1231 {
1232 if (field > 0 || (-field) > (INT_MAX - count - 1)) return NULL;
1233 if ((-field) == (INT_MAX - count - 1)) return s;
1234 while (field++ < 0)
1235 {
1236 ss--;
1237 while (ss[-1] != 0) ss--;
1238 }
1239 fieldtext = ss;
1240 break;
1241 }
1242
1243 /* Previous field was not last in the string; save its start and put a
1244 zero at its end. */
1245
1246 fieldtext = ss;
1247 len = Ustrcspn(ss, separators);
1248 sep = ss[len];
1249 ss[len] = 0;
1250 ss += len + 1;
1251 }
1252
1253 return fieldtext;
1254 }
1255
1256
1257 static uschar *
1258 expand_getlistele(int field, const uschar * list)
1259 {
1260 const uschar * tlist = list;
1261 int sep = 0;
1262 uschar dummy;
1263
1264 if (field < 0)
1265 {
1266 for (field++; string_nextinlist(&tlist, &sep, &dummy, 1); ) field++;
1267 sep = 0;
1268 }
1269 if (field == 0) return NULL;
1270 while (--field > 0 && (string_nextinlist(&list, &sep, &dummy, 1))) ;
1271 return string_nextinlist(&list, &sep, NULL, 0);
1272 }
1273
1274
1275 /* Certificate fields, by name. Worry about by-OID later */
1276 /* Names are chosen to not have common prefixes */
1277
1278 #ifdef SUPPORT_TLS
1279 typedef struct
1280 {
1281 uschar * name;
1282 int namelen;
1283 uschar * (*getfn)(void * cert, uschar * mod);
1284 } certfield;
1285 static certfield certfields[] =
1286 { /* linear search; no special order */
1287 { US"version", 7, &tls_cert_version },
1288 { US"serial_number", 13, &tls_cert_serial_number },
1289 { US"subject", 7, &tls_cert_subject },
1290 { US"notbefore", 9, &tls_cert_not_before },
1291 { US"notafter", 8, &tls_cert_not_after },
1292 { US"issuer", 6, &tls_cert_issuer },
1293 { US"signature", 9, &tls_cert_signature },
1294 { US"sig_algorithm", 13, &tls_cert_signature_algorithm },
1295 { US"subj_altname", 12, &tls_cert_subject_altname },
1296 { US"ocsp_uri", 8, &tls_cert_ocsp_uri },
1297 { US"crl_uri", 7, &tls_cert_crl_uri },
1298 };
1299
1300 static uschar *
1301 expand_getcertele(uschar * field, uschar * certvar)
1302 {
1303 var_entry * vp;
1304 certfield * cp;
1305
1306 if (!(vp = find_var_ent(certvar)))
1307 {
1308 expand_string_message =
1309 string_sprintf("no variable named \"%s\"", certvar);
1310 return NULL; /* Unknown variable name */
1311 }
1312 /* NB this stops us passing certs around in variable. Might
1313 want to do that in future */
1314 if (vp->type != vtype_cert)
1315 {
1316 expand_string_message =
1317 string_sprintf("\"%s\" is not a certificate", certvar);
1318 return NULL; /* Unknown variable name */
1319 }
1320 if (!*(void **)vp->value)
1321 return NULL;
1322
1323 if (*field >= '0' && *field <= '9')
1324 return tls_cert_ext_by_oid(*(void **)vp->value, field, 0);
1325
1326 for(cp = certfields;
1327 cp < certfields + nelem(certfields);
1328 cp++)
1329 if (Ustrncmp(cp->name, field, cp->namelen) == 0)
1330 {
1331 uschar * modifier = *(field += cp->namelen) == ','
1332 ? ++field : NULL;
1333 return (*cp->getfn)( *(void **)vp->value, modifier );
1334 }
1335
1336 expand_string_message =
1337 string_sprintf("bad field selector \"%s\" for certextract", field);
1338 return NULL;
1339 }
1340 #endif /*SUPPORT_TLS*/
1341
1342 /*************************************************
1343 * Extract a substring from a string *
1344 *************************************************/
1345
1346 /* Perform the ${substr or ${length expansion operations.
1347
1348 Arguments:
1349 subject the input string
1350 value1 the offset from the start of the input string to the start of
1351 the output string; if negative, count from the right.
1352 value2 the length of the output string, or negative (-1) for unset
1353 if value1 is positive, unset means "all after"
1354 if value1 is negative, unset means "all before"
1355 len set to the length of the returned string
1356
1357 Returns: pointer to the output string, or NULL if there is an error
1358 */
1359
1360 static uschar *
1361 extract_substr(uschar *subject, int value1, int value2, int *len)
1362 {
1363 int sublen = Ustrlen(subject);
1364
1365 if (value1 < 0) /* count from right */
1366 {
1367 value1 += sublen;
1368
1369 /* If the position is before the start, skip to the start, and adjust the
1370 length. If the length ends up negative, the substring is null because nothing
1371 can precede. This falls out naturally when the length is unset, meaning "all
1372 to the left". */
1373
1374 if (value1 < 0)
1375 {
1376 value2 += value1;
1377 if (value2 < 0) value2 = 0;
1378 value1 = 0;
1379 }
1380
1381 /* Otherwise an unset length => characters before value1 */
1382
1383 else if (value2 < 0)
1384 {
1385 value2 = value1;
1386 value1 = 0;
1387 }
1388 }
1389
1390 /* For a non-negative offset, if the starting position is past the end of the
1391 string, the result will be the null string. Otherwise, an unset length means
1392 "rest"; just set it to the maximum - it will be cut down below if necessary. */
1393
1394 else
1395 {
1396 if (value1 > sublen)
1397 {
1398 value1 = sublen;
1399 value2 = 0;
1400 }
1401 else if (value2 < 0) value2 = sublen;
1402 }
1403
1404 /* Cut the length down to the maximum possible for the offset value, and get
1405 the required characters. */
1406
1407 if (value1 + value2 > sublen) value2 = sublen - value1;
1408 *len = value2;
1409 return subject + value1;
1410 }
1411
1412
1413
1414
1415 /*************************************************
1416 * Old-style hash of a string *
1417 *************************************************/
1418
1419 /* Perform the ${hash expansion operation.
1420
1421 Arguments:
1422 subject the input string (an expanded substring)
1423 value1 the length of the output string; if greater or equal to the
1424 length of the input string, the input string is returned
1425 value2 the number of hash characters to use, or 26 if negative
1426 len set to the length of the returned string
1427
1428 Returns: pointer to the output string, or NULL if there is an error
1429 */
1430
1431 static uschar *
1432 compute_hash(uschar *subject, int value1, int value2, int *len)
1433 {
1434 int sublen = Ustrlen(subject);
1435
1436 if (value2 < 0) value2 = 26;
1437 else if (value2 > Ustrlen(hashcodes))
1438 {
1439 expand_string_message =
1440 string_sprintf("hash count \"%d\" too big", value2);
1441 return NULL;
1442 }
1443
1444 /* Calculate the hash text. We know it is shorter than the original string, so
1445 can safely place it in subject[] (we know that subject is always itself an
1446 expanded substring). */
1447
1448 if (value1 < sublen)
1449 {
1450 int c;
1451 int i = 0;
1452 int j = value1;
1453 while ((c = (subject[j])) != 0)
1454 {
1455 int shift = (c + j++) & 7;
1456 subject[i] ^= (c << shift) | (c >> (8-shift));
1457 if (++i >= value1) i = 0;
1458 }
1459 for (i = 0; i < value1; i++)
1460 subject[i] = hashcodes[(subject[i]) % value2];
1461 }
1462 else value1 = sublen;
1463
1464 *len = value1;
1465 return subject;
1466 }
1467
1468
1469
1470
1471 /*************************************************
1472 * Numeric hash of a string *
1473 *************************************************/
1474
1475 /* Perform the ${nhash expansion operation. The first characters of the
1476 string are treated as most important, and get the highest prime numbers.
1477
1478 Arguments:
1479 subject the input string
1480 value1 the maximum value of the first part of the result
1481 value2 the maximum value of the second part of the result,
1482 or negative to produce only a one-part result
1483 len set to the length of the returned string
1484
1485 Returns: pointer to the output string, or NULL if there is an error.
1486 */
1487
1488 static uschar *
1489 compute_nhash (uschar *subject, int value1, int value2, int *len)
1490 {
1491 uschar *s = subject;
1492 int i = 0;
1493 unsigned long int total = 0; /* no overflow */
1494
1495 while (*s != 0)
1496 {
1497 if (i == 0) i = nelem(prime) - 1;
1498 total += prime[i--] * (unsigned int)(*s++);
1499 }
1500
1501 /* If value2 is unset, just compute one number */
1502
1503 if (value2 < 0)
1504 s = string_sprintf("%lu", total % value1);
1505
1506 /* Otherwise do a div/mod hash */
1507
1508 else
1509 {
1510 total = total % (value1 * value2);
1511 s = string_sprintf("%lu/%lu", total/value2, total % value2);
1512 }
1513
1514 *len = Ustrlen(s);
1515 return s;
1516 }
1517
1518
1519
1520
1521
1522 /*************************************************
1523 * Find the value of a header or headers *
1524 *************************************************/
1525
1526 /* Multiple instances of the same header get concatenated, and this function
1527 can also return a concatenation of all the header lines. When concatenating
1528 specific headers that contain lists of addresses, a comma is inserted between
1529 them. Otherwise we use a straight concatenation. Because some messages can have
1530 pathologically large number of lines, there is a limit on the length that is
1531 returned.
1532
1533 Arguments:
1534 name the name of the header, without the leading $header_ or $h_,
1535 or NULL if a concatenation of all headers is required
1536 newsize return the size of memory block that was obtained; may be NULL
1537 if exists_only is TRUE
1538 flags FH_EXISTS_ONLY
1539 set if called from a def: test; don't need to build a string;
1540 just return a string that is not "" and not "0" if the header
1541 exists
1542 FH_WANT_RAW
1543 set if called for $rh_ or $rheader_ items; no processing,
1544 other than concatenating, will be done on the header. Also used
1545 for $message_headers_raw.
1546 FH_WANT_LIST
1547 Double colon chars in the content, and replace newline with
1548 colon between each element when concatenating; returning a
1549 colon-sep list (elements might contain newlines)
1550 charset name of charset to translate MIME words to; used only if
1551 want_raw is false; if NULL, no translation is done (this is
1552 used for $bh_ and $bheader_)
1553
1554 Returns: NULL if the header does not exist, else a pointer to a new
1555 store block
1556 */
1557
1558 static uschar *
1559 find_header(uschar *name, int *newsize, unsigned flags, uschar *charset)
1560 {
1561 BOOL found = !name;
1562 int len = name ? Ustrlen(name) : 0;
1563 BOOL comma = FALSE;
1564 header_line * h;
1565 gstring * g = NULL;
1566
1567 for (h = header_list; h; h = h->next)
1568 if (h->type != htype_old && h->text) /* NULL => Received: placeholder */
1569 if (!name || (len <= h->slen && strncmpic(name, h->text, len) == 0))
1570 {
1571 uschar * s, * t;
1572 size_t inc;
1573
1574 if (flags & FH_EXISTS_ONLY)
1575 return US"1"; /* don't need actual string */
1576
1577 found = TRUE;
1578 s = h->text + len; /* text to insert */
1579 if (!(flags & FH_WANT_RAW)) /* unless wanted raw, */
1580 while (isspace(*s)) s++; /* remove leading white space */
1581 t = h->text + h->slen; /* end-point */
1582
1583 /* Unless wanted raw, remove trailing whitespace, including the
1584 newline. */
1585
1586 if (flags & FH_WANT_LIST)
1587 while (t > s && t[-1] == '\n') t--;
1588 else if (!(flags & FH_WANT_RAW))
1589 {
1590 while (t > s && isspace(t[-1])) t--;
1591
1592 /* Set comma if handling a single header and it's one of those
1593 that contains an address list, except when asked for raw headers. Only
1594 need to do this once. */
1595
1596 if (name && !comma && Ustrchr("BCFRST", h->type)) comma = TRUE;
1597 }
1598
1599 /* Trim the header roughly if we're approaching limits */
1600 inc = t - s;
1601 if ((g ? g->ptr : 0) + inc > header_insert_maxlen)
1602 inc = header_insert_maxlen - (g ? g->ptr : 0);
1603
1604 /* For raw just copy the data; for a list, add the data as a colon-sep
1605 list-element; for comma-list add as an unchecked comma,newline sep
1606 list-elemment; for other nonraw add as an unchecked newline-sep list (we
1607 stripped trailing WS above including the newline). We ignore the potential
1608 expansion due to colon-doubling, just leaving the loop if the limit is met
1609 or exceeded. */
1610
1611 if (flags & FH_WANT_LIST)
1612 g = string_append_listele_n(g, ':', s, (unsigned)inc);
1613 else if (flags & FH_WANT_RAW)
1614 {
1615 g = string_catn(g, s, (unsigned)inc);
1616 (void) string_from_gstring(g);
1617 }
1618 else if (inc > 0)
1619 if (comma)
1620 g = string_append2_listele_n(g, US",\n", s, (unsigned)inc);
1621 else
1622 g = string_append2_listele_n(g, US"\n", s, (unsigned)inc);
1623
1624 if (g && g->ptr >= header_insert_maxlen) break;
1625 }
1626
1627 if (!found) return NULL; /* No header found */
1628 if (!g) return US"";
1629
1630 /* That's all we do for raw header expansion. */
1631
1632 *newsize = g->size;
1633 if (flags & FH_WANT_RAW)
1634 return g->s;
1635
1636 /* Otherwise do RFC 2047 decoding, translating the charset if requested.
1637 The rfc2047_decode2() function can return an error with decoded data if the
1638 charset translation fails. If decoding fails, it returns NULL. */
1639
1640 else
1641 {
1642 uschar *decoded, *error;
1643
1644 decoded = rfc2047_decode2(g->s, check_rfc2047_length, charset, '?', NULL,
1645 newsize, &error);
1646 if (error)
1647 {
1648 DEBUG(D_any) debug_printf("*** error in RFC 2047 decoding: %s\n"
1649 " input was: %s\n", error, g->s);
1650 }
1651 return decoded ? decoded : g->s;
1652 }
1653 }
1654
1655
1656
1657
1658 /* Append a "local" element to an Authentication-Results: header
1659 if this was a non-smtp message.
1660 */
1661
1662 static gstring *
1663 authres_local(gstring * g, const uschar * sysname)
1664 {
1665 if (!f.authentication_local)
1666 return g;
1667 g = string_append(g, 3, US";\n\tlocal=pass (non-smtp, ", sysname, US")");
1668 if (authenticated_id) g = string_append(g, 2, " u=", authenticated_id);
1669 return g;
1670 }
1671
1672
1673 /* Append an "iprev" element to an Authentication-Results: header
1674 if we have attempted to get the calling host's name.
1675 */
1676
1677 static gstring *
1678 authres_iprev(gstring * g)
1679 {
1680 if (sender_host_name)
1681 g = string_append(g, 3, US";\n\tiprev=pass (", sender_host_name, US")");
1682 else if (host_lookup_deferred)
1683 g = string_catn(g, US";\n\tiprev=temperror", 19);
1684 else if (host_lookup_failed)
1685 g = string_catn(g, US";\n\tiprev=fail", 13);
1686 else
1687 return g;
1688
1689 if (sender_host_address)
1690 g = string_append(g, 2, US" smtp.remote-ip=", sender_host_address);
1691 return g;
1692 }
1693
1694
1695
1696 /*************************************************
1697 * Return list of recipients *
1698 *************************************************/
1699 /* A recipients list is available only during system message filtering,
1700 during ACL processing after DATA, and while expanding pipe commands
1701 generated from a system filter, but not elsewhere. */
1702
1703 static uschar *
1704 fn_recipients(void)
1705 {
1706 uschar * s;
1707 gstring * g = NULL;
1708 int i;
1709
1710 if (!f.enable_dollar_recipients) return NULL;
1711
1712 for (i = 0; i < recipients_count; i++)
1713 {
1714 s = recipients_list[i].address;
1715 g = string_append2_listele_n(g, US", ", s, Ustrlen(s));
1716 }
1717 return g ? g->s : NULL;
1718 }
1719
1720
1721 /*************************************************
1722 * Find value of a variable *
1723 *************************************************/
1724
1725 /* The table of variables is kept in alphabetic order, so we can search it
1726 using a binary chop. The "choplen" variable is nothing to do with the binary
1727 chop.
1728
1729 Arguments:
1730 name the name of the variable being sought
1731 exists_only TRUE if this is a def: test; passed on to find_header()
1732 skipping TRUE => skip any processing evaluation; this is not the same as
1733 exists_only because def: may test for values that are first
1734 evaluated here
1735 newsize pointer to an int which is initially zero; if the answer is in
1736 a new memory buffer, *newsize is set to its size
1737
1738 Returns: NULL if the variable does not exist, or
1739 a pointer to the variable's contents, or
1740 something non-NULL if exists_only is TRUE
1741 */
1742
1743 static uschar *
1744 find_variable(uschar *name, BOOL exists_only, BOOL skipping, int *newsize)
1745 {
1746 var_entry * vp;
1747 uschar *s, *domain;
1748 uschar **ss;
1749 void * val;
1750
1751 /* Handle ACL variables, whose names are of the form acl_cxxx or acl_mxxx.
1752 Originally, xxx had to be a number in the range 0-9 (later 0-19), but from
1753 release 4.64 onwards arbitrary names are permitted, as long as the first 5
1754 characters are acl_c or acl_m and the sixth is either a digit or an underscore
1755 (this gave backwards compatibility at the changeover). There may be built-in
1756 variables whose names start acl_ but they should never start in this way. This
1757 slightly messy specification is a consequence of the history, needless to say.
1758
1759 If an ACL variable does not exist, treat it as empty, unless strict_acl_vars is
1760 set, in which case give an error. */
1761
1762 if ((Ustrncmp(name, "acl_c", 5) == 0 || Ustrncmp(name, "acl_m", 5) == 0) &&
1763 !isalpha(name[5]))
1764 {
1765 tree_node *node =
1766 tree_search((name[4] == 'c')? acl_var_c : acl_var_m, name + 4);
1767 return node ? node->data.ptr : strict_acl_vars ? NULL : US"";
1768 }
1769
1770 /* Handle $auth<n> variables. */
1771
1772 if (Ustrncmp(name, "auth", 4) == 0)
1773 {
1774 uschar *endptr;
1775 int n = Ustrtoul(name + 4, &endptr, 10);
1776 if (*endptr == 0 && n != 0 && n <= AUTH_VARS)
1777 return !auth_vars[n-1] ? US"" : auth_vars[n-1];
1778 }
1779 else if (Ustrncmp(name, "regex", 5) == 0)
1780 {
1781 uschar *endptr;
1782 int n = Ustrtoul(name + 5, &endptr, 10);
1783 if (*endptr == 0 && n != 0 && n <= REGEX_VARS)
1784 return !regex_vars[n-1] ? US"" : regex_vars[n-1];
1785 }
1786
1787 /* For all other variables, search the table */
1788
1789 if (!(vp = find_var_ent(name)))
1790 return NULL; /* Unknown variable name */
1791
1792 /* Found an existing variable. If in skipping state, the value isn't needed,
1793 and we want to avoid processing (such as looking up the host name). */
1794
1795 if (skipping)
1796 return US"";
1797
1798 val = vp->value;
1799 switch (vp->type)
1800 {
1801 case vtype_filter_int:
1802 if (!f.filter_running) return NULL;
1803 /* Fall through */
1804 /* VVVVVVVVVVVV */
1805 case vtype_int:
1806 sprintf(CS var_buffer, "%d", *(int *)(val)); /* Integer */
1807 return var_buffer;
1808
1809 case vtype_ino:
1810 sprintf(CS var_buffer, "%ld", (long int)(*(ino_t *)(val))); /* Inode */
1811 return var_buffer;
1812
1813 case vtype_gid:
1814 sprintf(CS var_buffer, "%ld", (long int)(*(gid_t *)(val))); /* gid */
1815 return var_buffer;
1816
1817 case vtype_uid:
1818 sprintf(CS var_buffer, "%ld", (long int)(*(uid_t *)(val))); /* uid */
1819 return var_buffer;
1820
1821 case vtype_bool:
1822 sprintf(CS var_buffer, "%s", *(BOOL *)(val) ? "yes" : "no"); /* bool */
1823 return var_buffer;
1824
1825 case vtype_stringptr: /* Pointer to string */
1826 return (s = *((uschar **)(val))) ? s : US"";
1827
1828 case vtype_pid:
1829 sprintf(CS var_buffer, "%d", (int)getpid()); /* pid */
1830 return var_buffer;
1831
1832 case vtype_load_avg:
1833 sprintf(CS var_buffer, "%d", OS_GETLOADAVG()); /* load_average */
1834 return var_buffer;
1835
1836 case vtype_host_lookup: /* Lookup if not done so */
1837 if ( !sender_host_name && sender_host_address
1838 && !host_lookup_failed && host_name_lookup() == OK)
1839 host_build_sender_fullhost();
1840 return sender_host_name ? sender_host_name : US"";
1841
1842 case vtype_localpart: /* Get local part from address */
1843 s = *((uschar **)(val));
1844 if (s == NULL) return US"";
1845 domain = Ustrrchr(s, '@');
1846 if (domain == NULL) return s;
1847 if (domain - s > sizeof(var_buffer) - 1)
1848 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "local part longer than " SIZE_T_FMT
1849 " in string expansion", sizeof(var_buffer));
1850 Ustrncpy(var_buffer, s, domain - s);
1851 var_buffer[domain - s] = 0;
1852 return var_buffer;
1853
1854 case vtype_domain: /* Get domain from address */
1855 s = *((uschar **)(val));
1856 if (s == NULL) return US"";
1857 domain = Ustrrchr(s, '@');
1858 return (domain == NULL)? US"" : domain + 1;
1859
1860 case vtype_msgheaders:
1861 return find_header(NULL, newsize, exists_only ? FH_EXISTS_ONLY : 0, NULL);
1862
1863 case vtype_msgheaders_raw:
1864 return find_header(NULL, newsize,
1865 exists_only ? FH_EXISTS_ONLY|FH_WANT_RAW : FH_WANT_RAW, NULL);
1866
1867 case vtype_msgbody: /* Pointer to msgbody string */
1868 case vtype_msgbody_end: /* Ditto, the end of the msg */
1869 ss = (uschar **)(val);
1870 if (!*ss && deliver_datafile >= 0) /* Read body when needed */
1871 {
1872 uschar *body;
1873 off_t start_offset = SPOOL_DATA_START_OFFSET;
1874 int len = message_body_visible;
1875 if (len > message_size) len = message_size;
1876 *ss = body = store_malloc(len+1);
1877 body[0] = 0;
1878 if (vp->type == vtype_msgbody_end)
1879 {
1880 struct stat statbuf;
1881 if (fstat(deliver_datafile, &statbuf) == 0)
1882 {
1883 start_offset = statbuf.st_size - len;
1884 if (start_offset < SPOOL_DATA_START_OFFSET)
1885 start_offset = SPOOL_DATA_START_OFFSET;
1886 }
1887 }
1888 if (lseek(deliver_datafile, start_offset, SEEK_SET) < 0)
1889 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "deliver_datafile lseek: %s",
1890 strerror(errno));
1891 len = read(deliver_datafile, body, len);
1892 if (len > 0)
1893 {
1894 body[len] = 0;
1895 if (message_body_newlines) /* Separate loops for efficiency */
1896 while (len > 0)
1897 { if (body[--len] == 0) body[len] = ' '; }
1898 else
1899 while (len > 0)
1900 { if (body[--len] == '\n' || body[len] == 0) body[len] = ' '; }
1901 }
1902 }
1903 return *ss ? *ss : US"";
1904
1905 case vtype_todbsdin: /* BSD inbox time of day */
1906 return tod_stamp(tod_bsdin);
1907
1908 case vtype_tode: /* Unix epoch time of day */
1909 return tod_stamp(tod_epoch);
1910
1911 case vtype_todel: /* Unix epoch/usec time of day */
1912 return tod_stamp(tod_epoch_l);
1913
1914 case vtype_todf: /* Full time of day */
1915 return tod_stamp(tod_full);
1916
1917 case vtype_todl: /* Log format time of day */
1918 return tod_stamp(tod_log_bare); /* (without timezone) */
1919
1920 case vtype_todzone: /* Time zone offset only */
1921 return tod_stamp(tod_zone);
1922
1923 case vtype_todzulu: /* Zulu time */
1924 return tod_stamp(tod_zulu);
1925
1926 case vtype_todlf: /* Log file datestamp tod */
1927 return tod_stamp(tod_log_datestamp_daily);
1928
1929 case vtype_reply: /* Get reply address */
1930 s = find_header(US"reply-to:", newsize,
1931 exists_only ? FH_EXISTS_ONLY|FH_WANT_RAW : FH_WANT_RAW,
1932 headers_charset);
1933 if (s) while (isspace(*s)) s++;
1934 if (!s || !*s)
1935 {
1936 *newsize = 0; /* For the *s==0 case */
1937 s = find_header(US"from:", newsize,
1938 exists_only ? FH_EXISTS_ONLY|FH_WANT_RAW : FH_WANT_RAW,
1939 headers_charset);
1940 }
1941 if (s)
1942 {
1943 uschar *t;
1944 while (isspace(*s)) s++;
1945 for (t = s; *t != 0; t++) if (*t == '\n') *t = ' ';
1946 while (t > s && isspace(t[-1])) t--;
1947 *t = 0;
1948 }
1949 return s ? s : US"";
1950
1951 case vtype_string_func:
1952 {
1953 uschar * (*fn)() = val;
1954 return fn();
1955 }
1956
1957 case vtype_pspace:
1958 {
1959 int inodes;
1960 sprintf(CS var_buffer, "%d",
1961 receive_statvfs(val == (void *)TRUE, &inodes));
1962 }
1963 return var_buffer;
1964
1965 case vtype_pinodes:
1966 {
1967 int inodes;
1968 (void) receive_statvfs(val == (void *)TRUE, &inodes);
1969 sprintf(CS var_buffer, "%d", inodes);
1970 }
1971 return var_buffer;
1972
1973 case vtype_cert:
1974 return *(void **)val ? US"<cert>" : US"";
1975
1976 #ifndef DISABLE_DKIM
1977 case vtype_dkim:
1978 return dkim_exim_expand_query((int)(long)val);
1979 #endif
1980
1981 }
1982
1983 return NULL; /* Unknown variable. Silences static checkers. */
1984 }
1985
1986
1987
1988
1989 void
1990 modify_variable(uschar *name, void * value)
1991 {
1992 var_entry * vp;
1993 if ((vp = find_var_ent(name))) vp->value = value;
1994 return; /* Unknown variable name, fail silently */
1995 }
1996
1997
1998
1999
2000
2001
2002 /*************************************************
2003 * Read and expand substrings *
2004 *************************************************/
2005
2006 /* This function is called to read and expand argument substrings for various
2007 expansion items. Some have a minimum requirement that is less than the maximum;
2008 in these cases, the first non-present one is set to NULL.
2009
2010 Arguments:
2011 sub points to vector of pointers to set
2012 n maximum number of substrings
2013 m minimum required
2014 sptr points to current string pointer
2015 skipping the skipping flag
2016 check_end if TRUE, check for final '}'
2017 name name of item, for error message
2018 resetok if not NULL, pointer to flag - write FALSE if unsafe to reset
2019 the store.
2020
2021 Returns: 0 OK; string pointer updated
2022 1 curly bracketing error (too few arguments)
2023 2 too many arguments (only if check_end is set); message set
2024 3 other error (expansion failure)
2025 */
2026
2027 static int
2028 read_subs(uschar **sub, int n, int m, const uschar **sptr, BOOL skipping,
2029 BOOL check_end, uschar *name, BOOL *resetok)
2030 {
2031 int i;
2032 const uschar *s = *sptr;
2033
2034 while (isspace(*s)) s++;
2035 for (i = 0; i < n; i++)
2036 {
2037 if (*s != '{')
2038 {
2039 if (i < m)
2040 {
2041 expand_string_message = string_sprintf("Not enough arguments for '%s' "
2042 "(min is %d)", name, m);
2043 return 1;
2044 }
2045 sub[i] = NULL;
2046 break;
2047 }
2048 if (!(sub[i] = expand_string_internal(s+1, TRUE, &s, skipping, TRUE, resetok)))
2049 return 3;
2050 if (*s++ != '}') return 1;
2051 while (isspace(*s)) s++;
2052 }
2053 if (check_end && *s++ != '}')
2054 {
2055 if (s[-1] == '{')
2056 {
2057 expand_string_message = string_sprintf("Too many arguments for '%s' "
2058 "(max is %d)", name, n);
2059 return 2;
2060 }
2061 expand_string_message = string_sprintf("missing '}' after '%s'", name);
2062 return 1;
2063 }
2064
2065 *sptr = s;
2066 return 0;
2067 }
2068
2069
2070
2071
2072 /*************************************************
2073 * Elaborate message for bad variable *
2074 *************************************************/
2075
2076 /* For the "unknown variable" message, take a look at the variable's name, and
2077 give additional information about possible ACL variables. The extra information
2078 is added on to expand_string_message.
2079
2080 Argument: the name of the variable
2081 Returns: nothing
2082 */
2083
2084 static void
2085 check_variable_error_message(uschar *name)
2086 {
2087 if (Ustrncmp(name, "acl_", 4) == 0)
2088 expand_string_message = string_sprintf("%s (%s)", expand_string_message,
2089 (name[4] == 'c' || name[4] == 'm')?
2090 (isalpha(name[5])?
2091 US"6th character of a user-defined ACL variable must be a digit or underscore" :
2092 US"strict_acl_vars is set" /* Syntax is OK, it has to be this */
2093 ) :
2094 US"user-defined ACL variables must start acl_c or acl_m");
2095 }
2096
2097
2098
2099 /*
2100 Load args from sub array to globals, and call acl_check().
2101 Sub array will be corrupted on return.
2102
2103 Returns: OK access is granted by an ACCEPT verb
2104 DISCARD access is (apparently) granted by a DISCARD verb
2105 FAIL access is denied
2106 FAIL_DROP access is denied; drop the connection
2107 DEFER can't tell at the moment
2108 ERROR disaster
2109 */
2110 static int
2111 eval_acl(uschar ** sub, int nsub, uschar ** user_msgp)
2112 {
2113 int i;
2114 int sav_narg = acl_narg;
2115 int ret;
2116 uschar * dummy_logmsg;
2117 extern int acl_where;
2118
2119 if(--nsub > nelem(acl_arg)) nsub = nelem(acl_arg);
2120 for (i = 0; i < nsub && sub[i+1]; i++)
2121 {
2122 uschar * tmp = acl_arg[i];
2123 acl_arg[i] = sub[i+1]; /* place callers args in the globals */
2124 sub[i+1] = tmp; /* stash the old args using our caller's storage */
2125 }
2126 acl_narg = i;
2127 while (i < nsub)
2128 {
2129 sub[i+1] = acl_arg[i];
2130 acl_arg[i++] = NULL;
2131 }
2132
2133 DEBUG(D_expand)
2134 debug_printf_indent("expanding: acl: %s arg: %s%s\n",
2135 sub[0],
2136 acl_narg>0 ? acl_arg[0] : US"<none>",
2137 acl_narg>1 ? " +more" : "");
2138
2139 ret = acl_eval(acl_where, sub[0], user_msgp, &dummy_logmsg);
2140
2141 for (i = 0; i < nsub; i++)
2142 acl_arg[i] = sub[i+1]; /* restore old args */
2143 acl_narg = sav_narg;
2144
2145 return ret;
2146 }
2147
2148
2149
2150
2151 /*************************************************
2152 * Read and evaluate a condition *
2153 *************************************************/
2154
2155 /*
2156 Arguments:
2157 s points to the start of the condition text
2158 resetok points to a BOOL which is written false if it is unsafe to
2159 free memory. Certain condition types (acl) may have side-effect
2160 allocation which must be preserved.
2161 yield points to a BOOL to hold the result of the condition test;
2162 if NULL, we are just reading through a condition that is
2163 part of an "or" combination to check syntax, or in a state
2164 where the answer isn't required
2165
2166 Returns: a pointer to the first character after the condition, or
2167 NULL after an error
2168 */
2169
2170 static const uschar *
2171 eval_condition(const uschar *s, BOOL *resetok, BOOL *yield)
2172 {
2173 BOOL testfor = TRUE;
2174 BOOL tempcond, combined_cond;
2175 BOOL *subcondptr;
2176 BOOL sub2_honour_dollar = TRUE;
2177 int i, rc, cond_type, roffset;
2178 int_eximarith_t num[2];
2179 struct stat statbuf;
2180 uschar name[256];
2181 const uschar *sub[10];
2182
2183 const pcre *re;
2184 const uschar *rerror;
2185
2186 for (;;)
2187 {
2188 while (isspace(*s)) s++;
2189 if (*s == '!') { testfor = !testfor; s++; } else break;
2190 }
2191
2192 /* Numeric comparisons are symbolic */
2193
2194 if (*s == '=' || *s == '>' || *s == '<')
2195 {
2196 int p = 0;
2197 name[p++] = *s++;
2198 if (*s == '=')
2199 {
2200 name[p++] = '=';
2201 s++;
2202 }
2203 name[p] = 0;
2204 }
2205
2206 /* All other conditions are named */
2207
2208 else s = read_name(name, 256, s, US"_");
2209
2210 /* If we haven't read a name, it means some non-alpha character is first. */
2211
2212 if (name[0] == 0)
2213 {
2214 expand_string_message = string_sprintf("condition name expected, "
2215 "but found \"%.16s\"", s);
2216 return NULL;
2217 }
2218
2219 /* Find which condition we are dealing with, and switch on it */
2220
2221 cond_type = chop_match(name, cond_table, nelem(cond_table));
2222 switch(cond_type)
2223 {
2224 /* def: tests for a non-empty variable, or for the existence of a header. If
2225 yield == NULL we are in a skipping state, and don't care about the answer. */
2226
2227 case ECOND_DEF:
2228 {
2229 uschar * t;
2230
2231 if (*s != ':')
2232 {
2233 expand_string_message = US"\":\" expected after \"def\"";
2234 return NULL;
2235 }
2236
2237 s = read_name(name, 256, s+1, US"_");
2238
2239 /* Test for a header's existence. If the name contains a closing brace
2240 character, this may be a user error where the terminating colon has been
2241 omitted. Set a flag to adjust a subsequent error message in this case. */
2242
2243 if ( ( *(t = name) == 'h'
2244 || (*t == 'r' || *t == 'l' || *t == 'b') && *++t == 'h'
2245 )
2246 && (*++t == '_' || Ustrncmp(t, "eader_", 6) == 0)
2247 )
2248 {
2249 s = read_header_name(name, 256, s);
2250 /* {-for-text-editors */
2251 if (Ustrchr(name, '}') != NULL) malformed_header = TRUE;
2252 if (yield) *yield =
2253 (find_header(name, NULL, FH_EXISTS_ONLY, NULL) != NULL) == testfor;
2254 }
2255
2256 /* Test for a variable's having a non-empty value. A non-existent variable
2257 causes an expansion failure. */
2258
2259 else
2260 {
2261 if (!(t = find_variable(name, TRUE, yield == NULL, NULL)))
2262 {
2263 expand_string_message = (name[0] == 0)?
2264 string_sprintf("variable name omitted after \"def:\"") :
2265 string_sprintf("unknown variable \"%s\" after \"def:\"", name);
2266 check_variable_error_message(name);
2267 return NULL;
2268 }
2269 if (yield) *yield = (t[0] != 0) == testfor;
2270 }
2271
2272 return s;
2273 }
2274
2275
2276 /* first_delivery tests for first delivery attempt */
2277
2278 case ECOND_FIRST_DELIVERY:
2279 if (yield != NULL) *yield = f.deliver_firsttime == testfor;
2280 return s;
2281
2282
2283 /* queue_running tests for any process started by a queue runner */
2284
2285 case ECOND_QUEUE_RUNNING:
2286 if (yield != NULL) *yield = (queue_run_pid != (pid_t)0) == testfor;
2287 return s;
2288
2289
2290 /* exists: tests for file existence
2291 isip: tests for any IP address
2292 isip4: tests for an IPv4 address
2293 isip6: tests for an IPv6 address
2294 pam: does PAM authentication
2295 radius: does RADIUS authentication
2296 ldapauth: does LDAP authentication
2297 pwcheck: does Cyrus SASL pwcheck authentication
2298 */
2299
2300 case ECOND_EXISTS:
2301 case ECOND_ISIP:
2302 case ECOND_ISIP4:
2303 case ECOND_ISIP6:
2304 case ECOND_PAM:
2305 case ECOND_RADIUS:
2306 case ECOND_LDAPAUTH:
2307 case ECOND_PWCHECK:
2308
2309 while (isspace(*s)) s++;
2310 if (*s != '{') goto COND_FAILED_CURLY_START; /* }-for-text-editors */
2311
2312 sub[0] = expand_string_internal(s+1, TRUE, &s, yield == NULL, TRUE, resetok);
2313 if (sub[0] == NULL) return NULL;
2314 /* {-for-text-editors */
2315 if (*s++ != '}') goto COND_FAILED_CURLY_END;
2316
2317 if (yield == NULL) return s; /* No need to run the test if skipping */
2318
2319 switch(cond_type)
2320 {
2321 case ECOND_EXISTS:
2322 if ((expand_forbid & RDO_EXISTS) != 0)
2323 {
2324 expand_string_message = US"File existence tests are not permitted";
2325 return NULL;
2326 }
2327 *yield = (Ustat(sub[0], &statbuf) == 0) == testfor;
2328 break;
2329
2330 case ECOND_ISIP:
2331 case ECOND_ISIP4:
2332 case ECOND_ISIP6:
2333 rc = string_is_ip_address(sub[0], NULL);
2334 *yield = ((cond_type == ECOND_ISIP)? (rc != 0) :
2335 (cond_type == ECOND_ISIP4)? (rc == 4) : (rc == 6)) == testfor;
2336 break;
2337
2338 /* Various authentication tests - all optionally compiled */
2339
2340 case ECOND_PAM:
2341 #ifdef SUPPORT_PAM
2342 rc = auth_call_pam(sub[0], &expand_string_message);
2343 goto END_AUTH;
2344 #else
2345 goto COND_FAILED_NOT_COMPILED;
2346 #endif /* SUPPORT_PAM */
2347
2348 case ECOND_RADIUS:
2349 #ifdef RADIUS_CONFIG_FILE
2350 rc = auth_call_radius(sub[0], &expand_string_message);
2351 goto END_AUTH;
2352 #else
2353 goto COND_FAILED_NOT_COMPILED;
2354 #endif /* RADIUS_CONFIG_FILE */
2355
2356 case ECOND_LDAPAUTH:
2357 #ifdef LOOKUP_LDAP
2358 {
2359 /* Just to keep the interface the same */
2360 BOOL do_cache;
2361 int old_pool = store_pool;
2362 store_pool = POOL_SEARCH;
2363 rc = eldapauth_find((void *)(-1), NULL, sub[0], Ustrlen(sub[0]), NULL,
2364 &expand_string_message, &do_cache);
2365 store_pool = old_pool;
2366 }
2367 goto END_AUTH;
2368 #else
2369 goto COND_FAILED_NOT_COMPILED;
2370 #endif /* LOOKUP_LDAP */
2371
2372 case ECOND_PWCHECK:
2373 #ifdef CYRUS_PWCHECK_SOCKET
2374 rc = auth_call_pwcheck(sub[0], &expand_string_message);
2375 goto END_AUTH;
2376 #else
2377 goto COND_FAILED_NOT_COMPILED;
2378 #endif /* CYRUS_PWCHECK_SOCKET */
2379
2380 #if defined(SUPPORT_PAM) || defined(RADIUS_CONFIG_FILE) || \
2381 defined(LOOKUP_LDAP) || defined(CYRUS_PWCHECK_SOCKET)
2382 END_AUTH:
2383 if (rc == ERROR || rc == DEFER) return NULL;
2384 *yield = (rc == OK) == testfor;
2385 #endif
2386 }
2387 return s;
2388
2389
2390 /* call ACL (in a conditional context). Accept true, deny false.
2391 Defer is a forced-fail. Anything set by message= goes to $value.
2392 Up to ten parameters are used; we use the braces round the name+args
2393 like the saslauthd condition does, to permit a variable number of args.
2394 See also the expansion-item version EITEM_ACL and the traditional
2395 acl modifier ACLC_ACL.
2396 Since the ACL may allocate new global variables, tell our caller to not
2397 reclaim memory.
2398 */
2399
2400 case ECOND_ACL:
2401 /* ${if acl {{name}{arg1}{arg2}...} {yes}{no}} */
2402 {
2403 uschar *sub[10];
2404 uschar *user_msg;
2405 BOOL cond = FALSE;
2406
2407 while (isspace(*s)) s++;
2408 if (*s++ != '{') goto COND_FAILED_CURLY_START; /*}*/
2409
2410 switch(read_subs(sub, nelem(sub), 1,
2411 &s, yield == NULL, TRUE, US"acl", resetok))
2412 {
2413 case 1: expand_string_message = US"too few arguments or bracketing "
2414 "error for acl";
2415 case 2:
2416 case 3: return NULL;
2417 }
2418
2419 if (yield != NULL)
2420 {
2421 *resetok = FALSE; /* eval_acl() might allocate; do not reclaim */
2422 switch(eval_acl(sub, nelem(sub), &user_msg))
2423 {
2424 case OK:
2425 cond = TRUE;
2426 case FAIL:
2427 lookup_value = NULL;
2428 if (user_msg)
2429 lookup_value = string_copy(user_msg);
2430 *yield = cond == testfor;
2431 break;
2432
2433 case DEFER:
2434 f.expand_string_forcedfail = TRUE;
2435 /*FALLTHROUGH*/
2436 default:
2437 expand_string_message = string_sprintf("error from acl \"%s\"", sub[0]);
2438 return NULL;
2439 }
2440 }
2441 return s;
2442 }
2443
2444
2445 /* saslauthd: does Cyrus saslauthd authentication. Four parameters are used:
2446
2447 ${if saslauthd {{username}{password}{service}{realm}} {yes}{no}}
2448
2449 However, the last two are optional. That is why the whole set is enclosed
2450 in their own set of braces. */
2451
2452 case ECOND_SASLAUTHD:
2453 #ifndef CYRUS_SASLAUTHD_SOCKET
2454 goto COND_FAILED_NOT_COMPILED;
2455 #else
2456 {
2457 uschar *sub[4];
2458 while (isspace(*s)) s++;
2459 if (*s++ != '{') goto COND_FAILED_CURLY_START; /* }-for-text-editors */
2460 switch(read_subs(sub, nelem(sub), 2, &s, yield == NULL, TRUE, US"saslauthd",
2461 resetok))
2462 {
2463 case 1: expand_string_message = US"too few arguments or bracketing "
2464 "error for saslauthd";
2465 case 2:
2466 case 3: return NULL;
2467 }
2468 if (sub[2] == NULL) sub[3] = NULL; /* realm if no service */
2469 if (yield != NULL)
2470 {
2471 int rc = auth_call_saslauthd(sub[0], sub[1], sub[2], sub[3],
2472 &expand_string_message);
2473 if (rc == ERROR || rc == DEFER) return NULL;
2474 *yield = (rc == OK) == testfor;
2475 }
2476 return s;
2477 }
2478 #endif /* CYRUS_SASLAUTHD_SOCKET */
2479
2480
2481 /* symbolic operators for numeric and string comparison, and a number of
2482 other operators, all requiring two arguments.
2483
2484 crypteq: encrypts plaintext and compares against an encrypted text,
2485 using crypt(), crypt16(), MD5 or SHA-1
2486 inlist/inlisti: checks if first argument is in the list of the second
2487 match: does a regular expression match and sets up the numerical
2488 variables if it succeeds
2489 match_address: matches in an address list
2490 match_domain: matches in a domain list
2491 match_ip: matches a host list that is restricted to IP addresses
2492 match_local_part: matches in a local part list
2493 */
2494
2495 case ECOND_MATCH_ADDRESS:
2496 case ECOND_MATCH_DOMAIN:
2497 case ECOND_MATCH_IP:
2498 case ECOND_MATCH_LOCAL_PART:
2499 #ifndef EXPAND_LISTMATCH_RHS
2500 sub2_honour_dollar = FALSE;
2501 #endif
2502 /* FALLTHROUGH */
2503
2504 case ECOND_CRYPTEQ:
2505 case ECOND_INLIST:
2506 case ECOND_INLISTI:
2507 case ECOND_MATCH:
2508
2509 case ECOND_NUM_L: /* Numerical comparisons */
2510 case ECOND_NUM_LE:
2511 case ECOND_NUM_E:
2512 case ECOND_NUM_EE:
2513 case ECOND_NUM_G:
2514 case ECOND_NUM_GE:
2515
2516 case ECOND_STR_LT: /* String comparisons */
2517 case ECOND_STR_LTI:
2518 case ECOND_STR_LE:
2519 case ECOND_STR_LEI:
2520 case ECOND_STR_EQ:
2521 case ECOND_STR_EQI:
2522 case ECOND_STR_GT:
2523 case ECOND_STR_GTI:
2524 case ECOND_STR_GE:
2525 case ECOND_STR_GEI:
2526
2527 for (i = 0; i < 2; i++)
2528 {
2529 /* Sometimes, we don't expand substrings; too many insecure configurations
2530 created using match_address{}{} and friends, where the second param
2531 includes information from untrustworthy sources. */
2532 BOOL honour_dollar = TRUE;
2533 if ((i > 0) && !sub2_honour_dollar)
2534 honour_dollar = FALSE;
2535
2536 while (isspace(*s)) s++;
2537 if (*s != '{')
2538 {
2539 if (i == 0) goto COND_FAILED_CURLY_START;
2540 expand_string_message = string_sprintf("missing 2nd string in {} "
2541 "after \"%s\"", name);
2542 return NULL;
2543 }
2544 if (!(sub[i] = expand_string_internal(s+1, TRUE, &s, yield == NULL,
2545 honour_dollar, resetok)))
2546 return NULL;
2547 DEBUG(D_expand) if (i == 1 && !sub2_honour_dollar && Ustrchr(sub[1], '$'))
2548 debug_printf_indent("WARNING: the second arg is NOT expanded,"
2549 " for security reasons\n");
2550 if (*s++ != '}') goto COND_FAILED_CURLY_END;
2551
2552 /* Convert to numerical if required; we know that the names of all the
2553 conditions that compare numbers do not start with a letter. This just saves
2554 checking for them individually. */
2555
2556 if (!isalpha(name[0]) && yield != NULL)
2557 if (sub[i][0] == 0)
2558 {
2559 num[i] = 0;
2560 DEBUG(D_expand)
2561 debug_printf_indent("empty string cast to zero for numerical comparison\n");
2562 }
2563 else
2564 {
2565 num[i] = expanded_string_integer(sub[i], FALSE);
2566 if (expand_string_message != NULL) return NULL;
2567 }
2568 }
2569
2570 /* Result not required */
2571
2572 if (yield == NULL) return s;
2573
2574 /* Do an appropriate comparison */
2575
2576 switch(cond_type)
2577 {
2578 case ECOND_NUM_E:
2579 case ECOND_NUM_EE:
2580 tempcond = (num[0] == num[1]);
2581 break;
2582
2583 case ECOND_NUM_G:
2584 tempcond = (num[0] > num[1]);
2585 break;
2586
2587 case ECOND_NUM_GE:
2588 tempcond = (num[0] >= num[1]);
2589 break;
2590
2591 case ECOND_NUM_L:
2592 tempcond = (num[0] < num[1]);
2593 break;
2594
2595 case ECOND_NUM_LE:
2596 tempcond = (num[0] <= num[1]);
2597 break;
2598
2599 case ECOND_STR_LT:
2600 tempcond = (Ustrcmp(sub[0], sub[1]) < 0);
2601 break;
2602
2603 case ECOND_STR_LTI:
2604 tempcond = (strcmpic(sub[0], sub[1]) < 0);
2605 break;
2606
2607 case ECOND_STR_LE:
2608 tempcond = (Ustrcmp(sub[0], sub[1]) <= 0);
2609 break;
2610
2611 case ECOND_STR_LEI:
2612 tempcond = (strcmpic(sub[0], sub[1]) <= 0);
2613 break;
2614
2615 case ECOND_STR_EQ:
2616 tempcond = (Ustrcmp(sub[0], sub[1]) == 0);
2617 break;
2618
2619 case ECOND_STR_EQI:
2620 tempcond = (strcmpic(sub[0], sub[1]) == 0);
2621 break;
2622
2623 case ECOND_STR_GT:
2624 tempcond = (Ustrcmp(sub[0], sub[1]) > 0);
2625 break;
2626
2627 case ECOND_STR_GTI:
2628 tempcond = (strcmpic(sub[0], sub[1]) > 0);
2629 break;
2630
2631 case ECOND_STR_GE:
2632 tempcond = (Ustrcmp(sub[0], sub[1]) >= 0);
2633 break;
2634
2635 case ECOND_STR_GEI:
2636 tempcond = (strcmpic(sub[0], sub[1]) >= 0);
2637 break;
2638
2639 case ECOND_MATCH: /* Regular expression match */
2640 re = pcre_compile(CS sub[1], PCRE_COPT, (const char **)&rerror, &roffset,
2641 NULL);
2642 if (re == NULL)
2643 {
2644 expand_string_message = string_sprintf("regular expression error in "
2645 "\"%s\": %s at offset %d", sub[1], rerror, roffset);
2646 return NULL;
2647 }
2648 tempcond = regex_match_and_setup(re, sub[0], 0, -1);
2649 break;
2650
2651 case ECOND_MATCH_ADDRESS: /* Match in an address list */
2652 rc = match_address_list(sub[0], TRUE, FALSE, &(sub[1]), NULL, -1, 0, NULL);
2653 goto MATCHED_SOMETHING;
2654
2655 case ECOND_MATCH_DOMAIN: /* Match in a domain list */
2656 rc = match_isinlist(sub[0], &(sub[1]), 0, &domainlist_anchor, NULL,
2657 MCL_DOMAIN + MCL_NOEXPAND, TRUE, NULL);
2658 goto MATCHED_SOMETHING;
2659
2660 case ECOND_MATCH_IP: /* Match IP address in a host list */
2661 if (sub[0][0] != 0 && string_is_ip_address(sub[0], NULL) == 0)
2662 {
2663 expand_string_message = string_sprintf("\"%s\" is not an IP address",
2664 sub[0]);
2665 return NULL;
2666 }
2667 else
2668 {
2669 unsigned int *nullcache = NULL;
2670 check_host_block cb;
2671
2672 cb.host_name = US"";
2673 cb.host_address = sub[0];
2674
2675 /* If the host address starts off ::ffff: it is an IPv6 address in
2676 IPv4-compatible mode. Find the IPv4 part for checking against IPv4
2677 addresses. */
2678
2679 cb.host_ipv4 = (Ustrncmp(cb.host_address, "::ffff:", 7) == 0)?
2680 cb.host_address + 7 : cb.host_address;
2681
2682 rc = match_check_list(
2683 &sub[1], /* the list */
2684 0, /* separator character */
2685 &hostlist_anchor, /* anchor pointer */
2686 &nullcache, /* cache pointer */
2687 check_host, /* function for testing */
2688 &cb, /* argument for function */
2689 MCL_HOST, /* type of check */
2690 sub[0], /* text for debugging */
2691 NULL); /* where to pass back data */
2692 }
2693 goto MATCHED_SOMETHING;
2694
2695 case ECOND_MATCH_LOCAL_PART:
2696 rc = match_isinlist(sub[0], &(sub[1]), 0, &localpartlist_anchor, NULL,
2697 MCL_LOCALPART + MCL_NOEXPAND, TRUE, NULL);
2698 /* Fall through */
2699 /* VVVVVVVVVVVV */
2700 MATCHED_SOMETHING:
2701 switch(rc)
2702 {
2703 case OK:
2704 tempcond = TRUE;
2705 break;
2706
2707 case FAIL:
2708 tempcond = FALSE;
2709 break;
2710
2711 case DEFER:
2712 expand_string_message = string_sprintf("unable to complete match "
2713 "against \"%s\": %s", sub[1], search_error_message);
2714 return NULL;
2715 }
2716
2717 break;
2718
2719 /* Various "encrypted" comparisons. If the second string starts with
2720 "{" then an encryption type is given. Default to crypt() or crypt16()
2721 (build-time choice). */
2722 /* }-for-text-editors */
2723
2724 case ECOND_CRYPTEQ:
2725 #ifndef SUPPORT_CRYPTEQ
2726 goto COND_FAILED_NOT_COMPILED;
2727 #else
2728 if (strncmpic(sub[1], US"{md5}", 5) == 0)
2729 {
2730 int sublen = Ustrlen(sub[1]+5);
2731 md5 base;
2732 uschar digest[16];
2733
2734 md5_start(&base);
2735 md5_end(&base, sub[0], Ustrlen(sub[0]), digest);
2736
2737 /* If the length that we are comparing against is 24, the MD5 digest
2738 is expressed as a base64 string. This is the way LDAP does it. However,
2739 some other software uses a straightforward hex representation. We assume
2740 this if the length is 32. Other lengths fail. */
2741
2742 if (sublen == 24)
2743 {
2744 uschar *coded = b64encode(digest, 16);
2745 DEBUG(D_auth) debug_printf("crypteq: using MD5+B64 hashing\n"
2746 " subject=%s\n crypted=%s\n", coded, sub[1]+5);
2747 tempcond = (Ustrcmp(coded, sub[1]+5) == 0);
2748 }
2749 else if (sublen == 32)
2750 {
2751 int i;
2752 uschar coded[36];
2753 for (i = 0; i < 16; i++) sprintf(CS (coded+2*i), "%02X", digest[i]);
2754 coded[32] = 0;
2755 DEBUG(D_auth) debug_printf("crypteq: using MD5+hex hashing\n"
2756 " subject=%s\n crypted=%s\n", coded, sub[1]+5);
2757 tempcond = (strcmpic(coded, sub[1]+5) == 0);
2758 }
2759 else
2760 {
2761 DEBUG(D_auth) debug_printf("crypteq: length for MD5 not 24 or 32: "
2762 "fail\n crypted=%s\n", sub[1]+5);
2763 tempcond = FALSE;
2764 }
2765 }
2766
2767 else if (strncmpic(sub[1], US"{sha1}", 6) == 0)
2768 {
2769 int sublen = Ustrlen(sub[1]+6);
2770 hctx h;
2771 uschar digest[20];
2772
2773 sha1_start(&h);
2774 sha1_end(&h, sub[0], Ustrlen(sub[0]), digest);
2775
2776 /* If the length that we are comparing against is 28, assume the SHA1
2777 digest is expressed as a base64 string. If the length is 40, assume a
2778 straightforward hex representation. Other lengths fail. */
2779
2780 if (sublen == 28)
2781 {
2782 uschar *coded = b64encode(digest, 20);
2783 DEBUG(D_auth) debug_printf("crypteq: using SHA1+B64 hashing\n"
2784 " subject=%s\n crypted=%s\n", coded, sub[1]+6);
2785 tempcond = (Ustrcmp(coded, sub[1]+6) == 0);
2786 }
2787 else if (sublen == 40)
2788 {
2789 int i;
2790 uschar coded[44];
2791 for (i = 0; i < 20; i++) sprintf(CS (coded+2*i), "%02X", digest[i]);
2792 coded[40] = 0;
2793 DEBUG(D_auth) debug_printf("crypteq: using SHA1+hex hashing\n"
2794 " subject=%s\n crypted=%s\n", coded, sub[1]+6);
2795 tempcond = (strcmpic(coded, sub[1]+6) == 0);
2796 }
2797 else
2798 {
2799 DEBUG(D_auth) debug_printf("crypteq: length for SHA-1 not 28 or 40: "
2800 "fail\n crypted=%s\n", sub[1]+6);
2801 tempcond = FALSE;
2802 }
2803 }
2804
2805 else /* {crypt} or {crypt16} and non-{ at start */
2806 /* }-for-text-editors */
2807 {
2808 int which = 0;
2809 uschar *coded;
2810
2811 if (strncmpic(sub[1], US"{crypt}", 7) == 0)
2812 {
2813 sub[1] += 7;
2814 which = 1;
2815 }
2816 else if (strncmpic(sub[1], US"{crypt16}", 9) == 0)
2817 {
2818 sub[1] += 9;
2819 which = 2;
2820 }
2821 else if (sub[1][0] == '{') /* }-for-text-editors */
2822 {
2823 expand_string_message = string_sprintf("unknown encryption mechanism "
2824 "in \"%s\"", sub[1]);
2825 return NULL;
2826 }
2827
2828 switch(which)
2829 {
2830 case 0: coded = US DEFAULT_CRYPT(CS sub[0], CS sub[1]); break;
2831 case 1: coded = US crypt(CS sub[0], CS sub[1]); break;
2832 default: coded = US crypt16(CS sub[0], CS sub[1]); break;
2833 }
2834
2835 #define STR(s) # s
2836 #define XSTR(s) STR(s)
2837 DEBUG(D_auth) debug_printf("crypteq: using %s()\n"
2838 " subject=%s\n crypted=%s\n",
2839 which == 0 ? XSTR(DEFAULT_CRYPT) : which == 1 ? "crypt" : "crypt16",
2840 coded, sub[1]);
2841 #undef STR
2842 #undef XSTR
2843
2844 /* If the encrypted string contains fewer than two characters (for the
2845 salt), force failure. Otherwise we get false positives: with an empty
2846 string the yield of crypt() is an empty string! */
2847
2848 if (coded)
2849 tempcond = Ustrlen(sub[1]) < 2 ? FALSE : Ustrcmp(coded, sub[1]) == 0;
2850 else if (errno == EINVAL)
2851 tempcond = FALSE;
2852 else
2853 {
2854 expand_string_message = string_sprintf("crypt error: %s\n",
2855 US strerror(errno));
2856 return NULL;
2857 }
2858 }
2859 break;
2860 #endif /* SUPPORT_CRYPTEQ */
2861
2862 case ECOND_INLIST:
2863 case ECOND_INLISTI:
2864 {
2865 const uschar * list = sub[1];
2866 int sep = 0;
2867 uschar *save_iterate_item = iterate_item;
2868 int (*compare)(const uschar *, const uschar *);
2869
2870 DEBUG(D_expand) debug_printf_indent("condition: %s item: %s\n", name, sub[0]);
2871
2872 tempcond = FALSE;
2873 compare = cond_type == ECOND_INLISTI
2874 ? strcmpic : (int (*)(const uschar *, const uschar *)) strcmp;
2875
2876 while ((iterate_item = string_nextinlist(&list, &sep, NULL, 0)))
2877 {
2878 DEBUG(D_expand) debug_printf_indent(" compare %s\n", iterate_item);
2879 if (compare(sub[0], iterate_item) == 0)
2880 {
2881 tempcond = TRUE;
2882 break;
2883 }
2884 }
2885 iterate_item = save_iterate_item;
2886 }
2887
2888 } /* Switch for comparison conditions */
2889
2890 *yield = tempcond == testfor;
2891 return s; /* End of comparison conditions */
2892
2893
2894 /* and/or: computes logical and/or of several conditions */
2895
2896 case ECOND_AND:
2897 case ECOND_OR:
2898 subcondptr = (yield == NULL)? NULL : &tempcond;
2899 combined_cond = (cond_type == ECOND_AND);
2900
2901 while (isspace(*s)) s++;
2902 if (*s++ != '{') goto COND_FAILED_CURLY_START; /* }-for-text-editors */
2903
2904 for (;;)
2905 {
2906 while (isspace(*s)) s++;
2907 /* {-for-text-editors */
2908 if (*s == '}') break;
2909 if (*s != '{') /* }-for-text-editors */
2910 {
2911 expand_string_message = string_sprintf("each subcondition "
2912 "inside an \"%s{...}\" condition must be in its own {}", name);
2913 return NULL;
2914 }
2915
2916 if (!(s = eval_condition(s+1, resetok, subcondptr)))
2917 {
2918 expand_string_message = string_sprintf("%s inside \"%s{...}\" condition",
2919 expand_string_message, name);
2920 return NULL;
2921 }
2922 while (isspace(*s)) s++;
2923
2924 /* {-for-text-editors */
2925 if (*s++ != '}')
2926 {
2927 /* {-for-text-editors */
2928 expand_string_message = string_sprintf("missing } at end of condition "
2929 "inside \"%s\" group", name);
2930 return NULL;
2931 }
2932
2933 if (yield != NULL)
2934 {
2935 if (cond_type == ECOND_AND)
2936 {
2937 combined_cond &= tempcond;
2938 if (!combined_cond) subcondptr = NULL; /* once false, don't */
2939 } /* evaluate any more */
2940 else
2941 {
2942 combined_cond |= tempcond;
2943 if (combined_cond) subcondptr = NULL; /* once true, don't */
2944 } /* evaluate any more */
2945 }
2946 }
2947
2948 if (yield != NULL) *yield = (combined_cond == testfor);
2949 return ++s;
2950
2951
2952 /* forall/forany: iterates a condition with different values */
2953
2954 case ECOND_FORALL:
2955 case ECOND_FORANY:
2956 {
2957 const uschar * list;
2958 int sep = 0;
2959 uschar *save_iterate_item = iterate_item;
2960
2961 DEBUG(D_expand) debug_printf_indent("condition: %s\n", name);
2962
2963 while (isspace(*s)) s++;
2964 if (*s++ != '{') goto COND_FAILED_CURLY_START; /* }-for-text-editors */
2965 sub[0] = expand_string_internal(s, TRUE, &s, (yield == NULL), TRUE, resetok);
2966 if (sub[0] == NULL) return NULL;
2967 /* {-for-text-editors */
2968 if (*s++ != '}') goto COND_FAILED_CURLY_END;
2969
2970 while (isspace(*s)) s++;
2971 if (*s++ != '{') goto COND_FAILED_CURLY_START; /* }-for-text-editors */
2972
2973 sub[1] = s;
2974
2975 /* Call eval_condition once, with result discarded (as if scanning a
2976 "false" part). This allows us to find the end of the condition, because if
2977 the list it empty, we won't actually evaluate the condition for real. */
2978
2979 if (!(s = eval_condition(sub[1], resetok, NULL)))
2980 {
2981 expand_string_message = string_sprintf("%s inside \"%s\" condition",
2982 expand_string_message, name);
2983 return NULL;
2984 }
2985 while (isspace(*s)) s++;
2986
2987 /* {-for-text-editors */
2988 if (*s++ != '}')
2989 {
2990 /* {-for-text-editors */
2991 expand_string_message = string_sprintf("missing } at end of condition "
2992 "inside \"%s\"", name);
2993 return NULL;
2994 }
2995
2996 if (yield != NULL) *yield = !testfor;
2997 list = sub[0];
2998 while ((iterate_item = string_nextinlist(&list, &sep, NULL, 0)) != NULL)
2999 {
3000 DEBUG(D_expand) debug_printf_indent("%s: $item = \"%s\"\n", name, iterate_item);
3001 if (!eval_condition(sub[1], resetok, &tempcond))
3002 {
3003 expand_string_message = string_sprintf("%s inside \"%s\" condition",
3004 expand_string_message, name);
3005 iterate_item = save_iterate_item;
3006 return NULL;
3007 }
3008 DEBUG(D_expand) debug_printf_indent("%s: condition evaluated to %s\n", name,
3009 tempcond? "true":"false");
3010
3011 if (yield != NULL) *yield = (tempcond == testfor);
3012 if (tempcond == (cond_type == ECOND_FORANY)) break;
3013 }
3014
3015 iterate_item = save_iterate_item;
3016 return s;
3017 }
3018
3019
3020 /* The bool{} expansion condition maps a string to boolean.
3021 The values supported should match those supported by the ACL condition
3022 (acl.c, ACLC_CONDITION) so that we keep to a minimum the different ideas
3023 of true/false. Note that Router "condition" rules have a different
3024 interpretation, where general data can be used and only a few values
3025 map to FALSE.
3026 Note that readconf.c boolean matching, for boolean configuration options,
3027 only matches true/yes/false/no.
3028 The bool_lax{} condition matches the Router logic, which is much more
3029 liberal. */
3030 case ECOND_BOOL:
3031 case ECOND_BOOL_LAX:
3032 {
3033 uschar *sub_arg[1];
3034 uschar *t, *t2;
3035 uschar *ourname;
3036 size_t len;
3037 BOOL boolvalue = FALSE;
3038 while (isspace(*s)) s++;
3039 if (*s != '{') goto COND_FAILED_CURLY_START; /* }-for-text-editors */
3040 ourname = cond_type == ECOND_BOOL_LAX ? US"bool_lax" : US"bool";
3041 switch(read_subs(sub_arg, 1, 1, &s, yield == NULL, FALSE, ourname, resetok))
3042 {
3043 case 1: expand_string_message = string_sprintf(
3044 "too few arguments or bracketing error for %s",
3045 ourname);
3046 /*FALLTHROUGH*/
3047 case 2:
3048 case 3: return NULL;
3049 }
3050 t = sub_arg[0];
3051 while (isspace(*t)) t++;
3052 len = Ustrlen(t);
3053 if (len)
3054 {
3055 /* trailing whitespace: seems like a good idea to ignore it too */
3056 t2 = t + len - 1;
3057 while (isspace(*t2)) t2--;
3058 if (t2 != (t + len))
3059 {
3060 *++t2 = '\0';
3061 len = t2 - t;
3062 }
3063 }
3064 DEBUG(D_expand)
3065 debug_printf_indent("considering %s: %s\n", ourname, len ? t : US"<empty>");
3066 /* logic for the lax case from expand_check_condition(), which also does
3067 expands, and the logic is both short and stable enough that there should
3068 be no maintenance burden from replicating it. */
3069 if (len == 0)
3070 boolvalue = FALSE;
3071 else if (*t == '-'
3072 ? Ustrspn(t+1, "0123456789") == len-1
3073 : Ustrspn(t, "0123456789") == len)
3074 {
3075 boolvalue = (Uatoi(t) == 0) ? FALSE : TRUE;
3076 /* expand_check_condition only does a literal string "0" check */
3077 if ((cond_type == ECOND_BOOL_LAX) && (len > 1))
3078 boolvalue = TRUE;
3079 }
3080 else if (strcmpic(t, US"true") == 0 || strcmpic(t, US"yes") == 0)
3081 boolvalue = TRUE;
3082 else if (strcmpic(t, US"false") == 0 || strcmpic(t, US"no") == 0)
3083 boolvalue = FALSE;
3084 else if (cond_type == ECOND_BOOL_LAX)
3085 boolvalue = TRUE;
3086 else
3087 {
3088 expand_string_message = string_sprintf("unrecognised boolean "
3089 "value \"%s\"", t);
3090 return NULL;
3091 }
3092 DEBUG(D_expand) debug_printf_indent("%s: condition evaluated to %s\n", ourname,
3093 boolvalue? "true":"false");
3094 if (yield != NULL) *yield = (boolvalue == testfor);
3095 return s;
3096 }
3097
3098 /* Unknown condition */
3099
3100 default:
3101 expand_string_message = string_sprintf("unknown condition \"%s\"", name);
3102 return NULL;
3103 } /* End switch on condition type */
3104
3105 /* Missing braces at start and end of data */
3106
3107 COND_FAILED_CURLY_START:
3108 expand_string_message = string_sprintf("missing { after \"%s\"", name);
3109 return NULL;
3110
3111 COND_FAILED_CURLY_END:
3112 expand_string_message = string_sprintf("missing } at end of \"%s\" condition",
3113 name);
3114 return NULL;
3115
3116 /* A condition requires code that is not compiled */
3117
3118 #if !defined(SUPPORT_PAM) || !defined(RADIUS_CONFIG_FILE) || \
3119 !defined(LOOKUP_LDAP) || !defined(CYRUS_PWCHECK_SOCKET) || \
3120 !defined(SUPPORT_CRYPTEQ) || !defined(CYRUS_SASLAUTHD_SOCKET)
3121 COND_FAILED_NOT_COMPILED:
3122 expand_string_message = string_sprintf("support for \"%s\" not compiled",
3123 name);
3124 return NULL;
3125 #endif
3126 }
3127
3128
3129
3130
3131 /*************************************************
3132 * Save numerical variables *
3133 *************************************************/
3134
3135 /* This function is called from items such as "if" that want to preserve and
3136 restore the numbered variables.
3137
3138 Arguments:
3139 save_expand_string points to an array of pointers to set
3140 save_expand_nlength points to an array of ints for the lengths
3141
3142 Returns: the value of expand max to save
3143 */
3144
3145 static int
3146 save_expand_strings(uschar **save_expand_nstring, int *save_expand_nlength)
3147 {
3148 int i;
3149 for (i = 0; i <= expand_nmax; i++)
3150 {
3151 save_expand_nstring[i] = expand_nstring[i];
3152 save_expand_nlength[i] = expand_nlength[i];
3153 }
3154 return expand_nmax;
3155 }
3156
3157
3158
3159 /*************************************************
3160 * Restore numerical variables *
3161 *************************************************/
3162
3163 /* This function restored saved values of numerical strings.
3164
3165 Arguments:
3166 save_expand_nmax the number of strings to restore
3167 save_expand_string points to an array of pointers
3168 save_expand_nlength points to an array of ints
3169
3170 Returns: nothing
3171 */
3172
3173 static void
3174 restore_expand_strings(int save_expand_nmax, uschar **save_expand_nstring,
3175 int *save_expand_nlength)
3176 {
3177 int i;
3178 expand_nmax = save_expand_nmax;
3179 for (i = 0; i <= expand_nmax; i++)
3180 {
3181 expand_nstring[i] = save_expand_nstring[i];
3182 expand_nlength[i] = save_expand_nlength[i];
3183 }
3184 }
3185
3186
3187
3188
3189
3190 /*************************************************
3191 * Handle yes/no substrings *
3192 *************************************************/
3193
3194 /* This function is used by ${if}, ${lookup} and ${extract} to handle the
3195 alternative substrings that depend on whether or not the condition was true,
3196 or the lookup or extraction succeeded. The substrings always have to be
3197 expanded, to check their syntax, but "skipping" is set when the result is not
3198 needed - this avoids unnecessary nested lookups.
3199
3200 Arguments:
3201 skipping TRUE if we were skipping when this item was reached
3202 yes TRUE if the first string is to be used, else use the second
3203 save_lookup a value to put back into lookup_value before the 2nd expansion
3204 sptr points to the input string pointer
3205 yieldptr points to the output growable-string pointer
3206 type "lookup", "if", "extract", "run", "env", "listextract" or
3207 "certextract" for error message
3208 resetok if not NULL, pointer to flag - write FALSE if unsafe to reset
3209 the store.
3210
3211 Returns: 0 OK; lookup_value has been reset to save_lookup
3212 1 expansion failed
3213 2 expansion failed because of bracketing error
3214 */
3215
3216 static int
3217 process_yesno(BOOL skipping, BOOL yes, uschar *save_lookup, const uschar **sptr,
3218 gstring ** yieldptr, uschar *type, BOOL *resetok)
3219 {
3220 int rc = 0;
3221 const uschar *s = *sptr; /* Local value */
3222 uschar *sub1, *sub2;
3223 const uschar * errwhere;
3224
3225 /* If there are no following strings, we substitute the contents of $value for
3226 lookups and for extractions in the success case. For the ${if item, the string
3227 "true" is substituted. In the fail case, nothing is substituted for all three
3228 items. */
3229
3230 while (isspace(*s)) s++;
3231 if (*s == '}')
3232 {
3233 if (type[0] == 'i')
3234 {
3235 if (yes && !skipping)
3236 *yieldptr = string_catn(*yieldptr, US"true", 4);
3237 }
3238 else
3239 {
3240 if (yes && lookup_value && !skipping)
3241 *yieldptr = string_cat(*yieldptr, lookup_value);
3242 lookup_value = save_lookup;
3243 }
3244 s++;
3245 goto RETURN;
3246 }
3247
3248 /* The first following string must be braced. */
3249
3250 if (*s++ != '{')
3251 {
3252 errwhere = US"'yes' part did not start with '{'";
3253 goto FAILED_CURLY;
3254 }
3255
3256 /* Expand the first substring. Forced failures are noticed only if we actually
3257 want this string. Set skipping in the call in the fail case (this will always
3258 be the case if we were already skipping). */
3259
3260 sub1 = expand_string_internal(s, TRUE, &s, !yes, TRUE, resetok);
3261 if (sub1 == NULL && (yes || !f.expand_string_forcedfail)) goto FAILED;
3262 f.expand_string_forcedfail = FALSE;
3263 if (*s++ != '}')
3264 {
3265 errwhere = US"'yes' part did not end with '}'";
3266 goto FAILED_CURLY;
3267 }
3268
3269 /* If we want the first string, add it to the output */
3270
3271 if (yes)
3272 *yieldptr = string_cat(*yieldptr, sub1);
3273
3274 /* If this is called from a lookup/env or a (cert)extract, we want to restore
3275 $value to what it was at the start of the item, so that it has this value
3276 during the second string expansion. For the call from "if" or "run" to this
3277 function, save_lookup is set to lookup_value, so that this statement does
3278 nothing. */
3279
3280 lookup_value = save_lookup;
3281
3282 /* There now follows either another substring, or "fail", or nothing. This
3283 time, forced failures are noticed only if we want the second string. We must
3284 set skipping in the nested call if we don't want this string, or if we were
3285 already skipping. */
3286
3287 while (isspace(*s)) s++;
3288 if (*s == '{')
3289 {
3290 sub2 = expand_string_internal(s+1, TRUE, &s, yes || skipping, TRUE, resetok);
3291 if (sub2 == NULL && (!yes || !f.expand_string_forcedfail)) goto FAILED;
3292 f.expand_string_forcedfail = FALSE;
3293 if (*s++ != '}')
3294 {
3295 errwhere = US"'no' part did not start with '{'";
3296 goto FAILED_CURLY;
3297 }
3298
3299 /* If we want the second string, add it to the output */
3300
3301 if (!yes)
3302 *yieldptr = string_cat(*yieldptr, sub2);
3303 }
3304
3305 /* If there is no second string, but the word "fail" is present when the use of
3306 the second string is wanted, set a flag indicating it was a forced failure
3307 rather than a syntactic error. Swallow the terminating } in case this is nested
3308 inside another lookup or if or extract. */
3309
3310 else if (*s != '}')
3311 {
3312 uschar name[256];
3313 /* deconst cast ok here as source is s anyway */
3314 s = US read_name(name, sizeof(name), s, US"_");
3315 if (Ustrcmp(name, "fail") == 0)
3316 {
3317 if (!yes && !skipping)
3318 {
3319 while (isspace(*s)) s++;
3320 if (*s++ != '}')
3321 {
3322 errwhere = US"did not close with '}' after forcedfail";
3323 goto FAILED_CURLY;
3324 }
3325 expand_string_message =
3326 string_sprintf("\"%s\" failed and \"fail\" requested", type);
3327 f.expand_string_forcedfail = TRUE;
3328 goto FAILED;
3329 }
3330 }
3331 else
3332 {
3333 expand_string_message =
3334 string_sprintf("syntax error in \"%s\" item - \"fail\" expected", type);
3335 goto FAILED;
3336 }
3337 }
3338
3339 /* All we have to do now is to check on the final closing brace. */
3340
3341 while (isspace(*s)) s++;
3342 if (*s++ != '}')
3343 {
3344 errwhere = US"did not close with '}'";
3345 goto FAILED_CURLY;
3346 }
3347
3348
3349 RETURN:
3350 /* Update the input pointer value before returning */
3351 *sptr = s;
3352 return rc;
3353
3354 FAILED_CURLY:
3355 /* Get here if there is a bracketing failure */
3356 expand_string_message = string_sprintf(