Merge branch 'acl'
[exim.git] / src / src / expand.c
1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
4
5 /* Copyright (c) University of Cambridge 1995 - 2012 */
6 /* See the file NOTICE for conditions of use and distribution. */
7
8
9 /* Functions for handling string expansion. */
10
11
12 #include "exim.h"
13
14 /* Recursively called function */
15
16 static uschar *expand_string_internal(uschar *, BOOL, uschar **, BOOL, BOOL);
17
18 #ifdef STAND_ALONE
19 #ifndef SUPPORT_CRYPTEQ
20 #define SUPPORT_CRYPTEQ
21 #endif
22 #endif
23
24 #ifdef LOOKUP_LDAP
25 #include "lookups/ldap.h"
26 #endif
27
28 #ifdef SUPPORT_CRYPTEQ
29 #ifdef CRYPT_H
30 #include <crypt.h>
31 #endif
32 #ifndef HAVE_CRYPT16
33 extern char* crypt16(char*, char*);
34 #endif
35 #endif
36
37 /* The handling of crypt16() is a mess. I will record below the analysis of the
38 mess that was sent to me. We decided, however, to make changing this very low
39 priority, because in practice people are moving away from the crypt()
40 algorithms nowadays, so it doesn't seem worth it.
41
42 <quote>
43 There is an algorithm named "crypt16" in Ultrix and Tru64. It crypts
44 the first 8 characters of the password using a 20-round version of crypt
45 (standard crypt does 25 rounds). It then crypts the next 8 characters,
46 or an empty block if the password is less than 9 characters, using a
47 20-round version of crypt and the same salt as was used for the first
48 block. Charaters after the first 16 are ignored. It always generates
49 a 16-byte hash, which is expressed together with the salt as a string
50 of 24 base 64 digits. Here are some links to peruse:
51
52 http://cvs.pld.org.pl/pam/pamcrypt/crypt16.c?rev=1.2
53 http://seclists.org/bugtraq/1999/Mar/0076.html
54
55 There's a different algorithm named "bigcrypt" in HP-UX, Digital Unix,
56 and OSF/1. This is the same as the standard crypt if given a password
57 of 8 characters or less. If given more, it first does the same as crypt
58 using the first 8 characters, then crypts the next 8 (the 9th to 16th)
59 using as salt the first two base 64 digits from the first hash block.
60 If the password is more than 16 characters then it crypts the 17th to 24th
61 characters using as salt the first two base 64 digits from the second hash
62 block. And so on: I've seen references to it cutting off the password at
63 40 characters (5 blocks), 80 (10 blocks), or 128 (16 blocks). Some links:
64
65 http://cvs.pld.org.pl/pam/pamcrypt/bigcrypt.c?rev=1.2
66 http://seclists.org/bugtraq/1999/Mar/0109.html
67 http://h30097.www3.hp.com/docs/base_doc/DOCUMENTATION/HTML/AA-Q0R2D-
68 TET1_html/sec.c222.html#no_id_208
69
70 Exim has something it calls "crypt16". It will either use a native
71 crypt16 or its own implementation. A native crypt16 will presumably
72 be the one that I called "crypt16" above. The internal "crypt16"
73 function, however, is a two-block-maximum implementation of what I called
74 "bigcrypt". The documentation matches the internal code.
75
76 I suspect that whoever did the "crypt16" stuff for Exim didn't realise
77 that crypt16 and bigcrypt were different things.
78
79 Exim uses the LDAP-style scheme identifier "{crypt16}" to refer
80 to whatever it is using under that name. This unfortunately sets a
81 precedent for using "{crypt16}" to identify two incompatible algorithms
82 whose output can't be distinguished. With "{crypt16}" thus rendered
83 ambiguous, I suggest you deprecate it and invent two new identifiers
84 for the two algorithms.
85
86 Both crypt16 and bigcrypt are very poor algorithms, btw. Hashing parts
87 of the password separately means they can be cracked separately, so
88 the double-length hash only doubles the cracking effort instead of
89 squaring it. I recommend salted SHA-1 ({SSHA}), or the Blowfish-based
90 bcrypt ({CRYPT}$2a$).
91 </quote>
92 */
93
94
95
96
97 /*************************************************
98 * Local statics and tables *
99 *************************************************/
100
101 /* Table of item names, and corresponding switch numbers. The names must be in
102 alphabetical order. */
103
104 static uschar *item_table[] = {
105 US"acl",
106 US"dlfunc",
107 US"extract",
108 US"filter",
109 US"hash",
110 US"hmac",
111 US"if",
112 US"length",
113 US"lookup",
114 US"map",
115 US"nhash",
116 US"perl",
117 US"prvs",
118 US"prvscheck",
119 US"readfile",
120 US"readsocket",
121 US"reduce",
122 US"run",
123 US"sg",
124 US"substr",
125 US"tr" };
126
127 enum {
128 EITEM_ACL,
129 EITEM_DLFUNC,
130 EITEM_EXTRACT,
131 EITEM_FILTER,
132 EITEM_HASH,
133 EITEM_HMAC,
134 EITEM_IF,
135 EITEM_LENGTH,
136 EITEM_LOOKUP,
137 EITEM_MAP,
138 EITEM_NHASH,
139 EITEM_PERL,
140 EITEM_PRVS,
141 EITEM_PRVSCHECK,
142 EITEM_READFILE,
143 EITEM_READSOCK,
144 EITEM_REDUCE,
145 EITEM_RUN,
146 EITEM_SG,
147 EITEM_SUBSTR,
148 EITEM_TR };
149
150 /* Tables of operator names, and corresponding switch numbers. The names must be
151 in alphabetical order. There are two tables, because underscore is used in some
152 cases to introduce arguments, whereas for other it is part of the name. This is
153 an historical mis-design. */
154
155 static uschar *op_table_underscore[] = {
156 US"from_utf8",
157 US"local_part",
158 US"quote_local_part",
159 US"reverse_ip",
160 US"time_eval",
161 US"time_interval"};
162
163 enum {
164 EOP_FROM_UTF8,
165 EOP_LOCAL_PART,
166 EOP_QUOTE_LOCAL_PART,
167 EOP_REVERSE_IP,
168 EOP_TIME_EVAL,
169 EOP_TIME_INTERVAL };
170
171 static uschar *op_table_main[] = {
172 US"address",
173 US"addresses",
174 US"base62",
175 US"base62d",
176 US"domain",
177 US"escape",
178 US"eval",
179 US"eval10",
180 US"expand",
181 US"h",
182 US"hash",
183 US"hex2b64",
184 US"l",
185 US"lc",
186 US"length",
187 US"listcount",
188 US"listnamed",
189 US"mask",
190 US"md5",
191 US"nh",
192 US"nhash",
193 US"quote",
194 US"randint",
195 US"rfc2047",
196 US"rfc2047d",
197 US"rxquote",
198 US"s",
199 US"sha1",
200 US"stat",
201 US"str2b64",
202 US"strlen",
203 US"substr",
204 US"uc" };
205
206 enum {
207 EOP_ADDRESS = sizeof(op_table_underscore)/sizeof(uschar *),
208 EOP_ADDRESSES,
209 EOP_BASE62,
210 EOP_BASE62D,
211 EOP_DOMAIN,
212 EOP_ESCAPE,
213 EOP_EVAL,
214 EOP_EVAL10,
215 EOP_EXPAND,
216 EOP_H,
217 EOP_HASH,
218 EOP_HEX2B64,
219 EOP_L,
220 EOP_LC,
221 EOP_LENGTH,
222 EOP_LISTCOUNT,
223 EOP_LISTNAMED,
224 EOP_MASK,
225 EOP_MD5,
226 EOP_NH,
227 EOP_NHASH,
228 EOP_QUOTE,
229 EOP_RANDINT,
230 EOP_RFC2047,
231 EOP_RFC2047D,
232 EOP_RXQUOTE,
233 EOP_S,
234 EOP_SHA1,
235 EOP_STAT,
236 EOP_STR2B64,
237 EOP_STRLEN,
238 EOP_SUBSTR,
239 EOP_UC };
240
241
242 /* Table of condition names, and corresponding switch numbers. The names must
243 be in alphabetical order. */
244
245 static uschar *cond_table[] = {
246 US"<",
247 US"<=",
248 US"=",
249 US"==", /* Backward compatibility */
250 US">",
251 US">=",
252 US"acl",
253 US"and",
254 US"bool",
255 US"bool_lax",
256 US"crypteq",
257 US"def",
258 US"eq",
259 US"eqi",
260 US"exists",
261 US"first_delivery",
262 US"forall",
263 US"forany",
264 US"ge",
265 US"gei",
266 US"gt",
267 US"gti",
268 US"inlist",
269 US"inlisti",
270 US"isip",
271 US"isip4",
272 US"isip6",
273 US"ldapauth",
274 US"le",
275 US"lei",
276 US"lt",
277 US"lti",
278 US"match",
279 US"match_address",
280 US"match_domain",
281 US"match_ip",
282 US"match_local_part",
283 US"or",
284 US"pam",
285 US"pwcheck",
286 US"queue_running",
287 US"radius",
288 US"saslauthd"
289 };
290
291 enum {
292 ECOND_NUM_L,
293 ECOND_NUM_LE,
294 ECOND_NUM_E,
295 ECOND_NUM_EE,
296 ECOND_NUM_G,
297 ECOND_NUM_GE,
298 ECOND_ACL,
299 ECOND_AND,
300 ECOND_BOOL,
301 ECOND_BOOL_LAX,
302 ECOND_CRYPTEQ,
303 ECOND_DEF,
304 ECOND_STR_EQ,
305 ECOND_STR_EQI,
306 ECOND_EXISTS,
307 ECOND_FIRST_DELIVERY,
308 ECOND_FORALL,
309 ECOND_FORANY,
310 ECOND_STR_GE,
311 ECOND_STR_GEI,
312 ECOND_STR_GT,
313 ECOND_STR_GTI,
314 ECOND_INLIST,
315 ECOND_INLISTI,
316 ECOND_ISIP,
317 ECOND_ISIP4,
318 ECOND_ISIP6,
319 ECOND_LDAPAUTH,
320 ECOND_STR_LE,
321 ECOND_STR_LEI,
322 ECOND_STR_LT,
323 ECOND_STR_LTI,
324 ECOND_MATCH,
325 ECOND_MATCH_ADDRESS,
326 ECOND_MATCH_DOMAIN,
327 ECOND_MATCH_IP,
328 ECOND_MATCH_LOCAL_PART,
329 ECOND_OR,
330 ECOND_PAM,
331 ECOND_PWCHECK,
332 ECOND_QUEUE_RUNNING,
333 ECOND_RADIUS,
334 ECOND_SASLAUTHD
335 };
336
337
338 /* Type for main variable table */
339
340 typedef struct {
341 const char *name;
342 int type;
343 void *value;
344 } var_entry;
345
346 /* Type for entries pointing to address/length pairs. Not currently
347 in use. */
348
349 typedef struct {
350 uschar **address;
351 int *length;
352 } alblock;
353
354 /* Types of table entry */
355
356 enum {
357 vtype_int, /* value is address of int */
358 vtype_filter_int, /* ditto, but recognized only when filtering */
359 vtype_ino, /* value is address of ino_t (not always an int) */
360 vtype_uid, /* value is address of uid_t (not always an int) */
361 vtype_gid, /* value is address of gid_t (not always an int) */
362 vtype_bool, /* value is address of bool */
363 vtype_stringptr, /* value is address of pointer to string */
364 vtype_msgbody, /* as stringptr, but read when first required */
365 vtype_msgbody_end, /* ditto, the end of the message */
366 vtype_msgheaders, /* the message's headers, processed */
367 vtype_msgheaders_raw, /* the message's headers, unprocessed */
368 vtype_localpart, /* extract local part from string */
369 vtype_domain, /* extract domain from string */
370 vtype_recipients, /* extract recipients from recipients list */
371 /* (available only in system filters, ACLs, and */
372 /* local_scan()) */
373 vtype_todbsdin, /* value not used; generate BSD inbox tod */
374 vtype_tode, /* value not used; generate tod in epoch format */
375 vtype_todel, /* value not used; generate tod in epoch/usec format */
376 vtype_todf, /* value not used; generate full tod */
377 vtype_todl, /* value not used; generate log tod */
378 vtype_todlf, /* value not used; generate log file datestamp tod */
379 vtype_todzone, /* value not used; generate time zone only */
380 vtype_todzulu, /* value not used; generate zulu tod */
381 vtype_reply, /* value not used; get reply from headers */
382 vtype_pid, /* value not used; result is pid */
383 vtype_host_lookup, /* value not used; get host name */
384 vtype_load_avg, /* value not used; result is int from os_getloadavg */
385 vtype_pspace, /* partition space; value is T/F for spool/log */
386 vtype_pinodes /* partition inodes; value is T/F for spool/log */
387 #ifndef DISABLE_DKIM
388 ,vtype_dkim /* Lookup of value in DKIM signature */
389 #endif
390 };
391
392 /* This table must be kept in alphabetical order. */
393
394 static var_entry var_table[] = {
395 /* WARNING: Do not invent variables whose names start acl_c or acl_m because
396 they will be confused with user-creatable ACL variables. */
397 { "acl_arg1", vtype_stringptr, &acl_arg[0] },
398 { "acl_arg2", vtype_stringptr, &acl_arg[1] },
399 { "acl_arg3", vtype_stringptr, &acl_arg[2] },
400 { "acl_arg4", vtype_stringptr, &acl_arg[3] },
401 { "acl_arg5", vtype_stringptr, &acl_arg[4] },
402 { "acl_arg6", vtype_stringptr, &acl_arg[5] },
403 { "acl_arg7", vtype_stringptr, &acl_arg[6] },
404 { "acl_arg8", vtype_stringptr, &acl_arg[7] },
405 { "acl_arg9", vtype_stringptr, &acl_arg[8] },
406 { "acl_narg", vtype_int, &acl_narg },
407 { "acl_verify_message", vtype_stringptr, &acl_verify_message },
408 { "address_data", vtype_stringptr, &deliver_address_data },
409 { "address_file", vtype_stringptr, &address_file },
410 { "address_pipe", vtype_stringptr, &address_pipe },
411 { "authenticated_id", vtype_stringptr, &authenticated_id },
412 { "authenticated_sender",vtype_stringptr, &authenticated_sender },
413 { "authentication_failed",vtype_int, &authentication_failed },
414 #ifdef WITH_CONTENT_SCAN
415 { "av_failed", vtype_int, &av_failed },
416 #endif
417 #ifdef EXPERIMENTAL_BRIGHTMAIL
418 { "bmi_alt_location", vtype_stringptr, &bmi_alt_location },
419 { "bmi_base64_tracker_verdict", vtype_stringptr, &bmi_base64_tracker_verdict },
420 { "bmi_base64_verdict", vtype_stringptr, &bmi_base64_verdict },
421 { "bmi_deliver", vtype_int, &bmi_deliver },
422 #endif
423 { "body_linecount", vtype_int, &body_linecount },
424 { "body_zerocount", vtype_int, &body_zerocount },
425 { "bounce_recipient", vtype_stringptr, &bounce_recipient },
426 { "bounce_return_size_limit", vtype_int, &bounce_return_size_limit },
427 { "caller_gid", vtype_gid, &real_gid },
428 { "caller_uid", vtype_uid, &real_uid },
429 { "compile_date", vtype_stringptr, &version_date },
430 { "compile_number", vtype_stringptr, &version_cnumber },
431 { "csa_status", vtype_stringptr, &csa_status },
432 #ifdef EXPERIMENTAL_DCC
433 { "dcc_header", vtype_stringptr, &dcc_header },
434 { "dcc_result", vtype_stringptr, &dcc_result },
435 #endif
436 #ifdef WITH_OLD_DEMIME
437 { "demime_errorlevel", vtype_int, &demime_errorlevel },
438 { "demime_reason", vtype_stringptr, &demime_reason },
439 #endif
440 #ifndef DISABLE_DKIM
441 { "dkim_algo", vtype_dkim, (void *)DKIM_ALGO },
442 { "dkim_bodylength", vtype_dkim, (void *)DKIM_BODYLENGTH },
443 { "dkim_canon_body", vtype_dkim, (void *)DKIM_CANON_BODY },
444 { "dkim_canon_headers", vtype_dkim, (void *)DKIM_CANON_HEADERS },
445 { "dkim_copiedheaders", vtype_dkim, (void *)DKIM_COPIEDHEADERS },
446 { "dkim_created", vtype_dkim, (void *)DKIM_CREATED },
447 { "dkim_cur_signer", vtype_stringptr, &dkim_cur_signer },
448 { "dkim_domain", vtype_stringptr, &dkim_signing_domain },
449 { "dkim_expires", vtype_dkim, (void *)DKIM_EXPIRES },
450 { "dkim_headernames", vtype_dkim, (void *)DKIM_HEADERNAMES },
451 { "dkim_identity", vtype_dkim, (void *)DKIM_IDENTITY },
452 { "dkim_key_granularity",vtype_dkim, (void *)DKIM_KEY_GRANULARITY },
453 { "dkim_key_nosubdomains",vtype_dkim, (void *)DKIM_NOSUBDOMAINS },
454 { "dkim_key_notes", vtype_dkim, (void *)DKIM_KEY_NOTES },
455 { "dkim_key_srvtype", vtype_dkim, (void *)DKIM_KEY_SRVTYPE },
456 { "dkim_key_testing", vtype_dkim, (void *)DKIM_KEY_TESTING },
457 { "dkim_selector", vtype_stringptr, &dkim_signing_selector },
458 { "dkim_signers", vtype_stringptr, &dkim_signers },
459 { "dkim_verify_reason", vtype_dkim, (void *)DKIM_VERIFY_REASON },
460 { "dkim_verify_status", vtype_dkim, (void *)DKIM_VERIFY_STATUS},
461 #endif
462 { "dnslist_domain", vtype_stringptr, &dnslist_domain },
463 { "dnslist_matched", vtype_stringptr, &dnslist_matched },
464 { "dnslist_text", vtype_stringptr, &dnslist_text },
465 { "dnslist_value", vtype_stringptr, &dnslist_value },
466 { "domain", vtype_stringptr, &deliver_domain },
467 { "domain_data", vtype_stringptr, &deliver_domain_data },
468 { "exim_gid", vtype_gid, &exim_gid },
469 { "exim_path", vtype_stringptr, &exim_path },
470 { "exim_uid", vtype_uid, &exim_uid },
471 #ifdef WITH_OLD_DEMIME
472 { "found_extension", vtype_stringptr, &found_extension },
473 #endif
474 { "home", vtype_stringptr, &deliver_home },
475 { "host", vtype_stringptr, &deliver_host },
476 { "host_address", vtype_stringptr, &deliver_host_address },
477 { "host_data", vtype_stringptr, &host_data },
478 { "host_lookup_deferred",vtype_int, &host_lookup_deferred },
479 { "host_lookup_failed", vtype_int, &host_lookup_failed },
480 { "inode", vtype_ino, &deliver_inode },
481 { "interface_address", vtype_stringptr, &interface_address },
482 { "interface_port", vtype_int, &interface_port },
483 { "item", vtype_stringptr, &iterate_item },
484 #ifdef LOOKUP_LDAP
485 { "ldap_dn", vtype_stringptr, &eldap_dn },
486 #endif
487 { "load_average", vtype_load_avg, NULL },
488 { "local_part", vtype_stringptr, &deliver_localpart },
489 { "local_part_data", vtype_stringptr, &deliver_localpart_data },
490 { "local_part_prefix", vtype_stringptr, &deliver_localpart_prefix },
491 { "local_part_suffix", vtype_stringptr, &deliver_localpart_suffix },
492 { "local_scan_data", vtype_stringptr, &local_scan_data },
493 { "local_user_gid", vtype_gid, &local_user_gid },
494 { "local_user_uid", vtype_uid, &local_user_uid },
495 { "localhost_number", vtype_int, &host_number },
496 { "log_inodes", vtype_pinodes, (void *)FALSE },
497 { "log_space", vtype_pspace, (void *)FALSE },
498 { "mailstore_basename", vtype_stringptr, &mailstore_basename },
499 #ifdef WITH_CONTENT_SCAN
500 { "malware_name", vtype_stringptr, &malware_name },
501 #endif
502 { "max_received_linelength", vtype_int, &max_received_linelength },
503 { "message_age", vtype_int, &message_age },
504 { "message_body", vtype_msgbody, &message_body },
505 { "message_body_end", vtype_msgbody_end, &message_body_end },
506 { "message_body_size", vtype_int, &message_body_size },
507 { "message_exim_id", vtype_stringptr, &message_id },
508 { "message_headers", vtype_msgheaders, NULL },
509 { "message_headers_raw", vtype_msgheaders_raw, NULL },
510 { "message_id", vtype_stringptr, &message_id },
511 { "message_linecount", vtype_int, &message_linecount },
512 { "message_size", vtype_int, &message_size },
513 #ifdef WITH_CONTENT_SCAN
514 { "mime_anomaly_level", vtype_int, &mime_anomaly_level },
515 { "mime_anomaly_text", vtype_stringptr, &mime_anomaly_text },
516 { "mime_boundary", vtype_stringptr, &mime_boundary },
517 { "mime_charset", vtype_stringptr, &mime_charset },
518 { "mime_content_description", vtype_stringptr, &mime_content_description },
519 { "mime_content_disposition", vtype_stringptr, &mime_content_disposition },
520 { "mime_content_id", vtype_stringptr, &mime_content_id },
521 { "mime_content_size", vtype_int, &mime_content_size },
522 { "mime_content_transfer_encoding",vtype_stringptr, &mime_content_transfer_encoding },
523 { "mime_content_type", vtype_stringptr, &mime_content_type },
524 { "mime_decoded_filename", vtype_stringptr, &mime_decoded_filename },
525 { "mime_filename", vtype_stringptr, &mime_filename },
526 { "mime_is_coverletter", vtype_int, &mime_is_coverletter },
527 { "mime_is_multipart", vtype_int, &mime_is_multipart },
528 { "mime_is_rfc822", vtype_int, &mime_is_rfc822 },
529 { "mime_part_count", vtype_int, &mime_part_count },
530 #endif
531 { "n0", vtype_filter_int, &filter_n[0] },
532 { "n1", vtype_filter_int, &filter_n[1] },
533 { "n2", vtype_filter_int, &filter_n[2] },
534 { "n3", vtype_filter_int, &filter_n[3] },
535 { "n4", vtype_filter_int, &filter_n[4] },
536 { "n5", vtype_filter_int, &filter_n[5] },
537 { "n6", vtype_filter_int, &filter_n[6] },
538 { "n7", vtype_filter_int, &filter_n[7] },
539 { "n8", vtype_filter_int, &filter_n[8] },
540 { "n9", vtype_filter_int, &filter_n[9] },
541 { "original_domain", vtype_stringptr, &deliver_domain_orig },
542 { "original_local_part", vtype_stringptr, &deliver_localpart_orig },
543 { "originator_gid", vtype_gid, &originator_gid },
544 { "originator_uid", vtype_uid, &originator_uid },
545 { "parent_domain", vtype_stringptr, &deliver_domain_parent },
546 { "parent_local_part", vtype_stringptr, &deliver_localpart_parent },
547 { "pid", vtype_pid, NULL },
548 { "primary_hostname", vtype_stringptr, &primary_hostname },
549 { "prvscheck_address", vtype_stringptr, &prvscheck_address },
550 { "prvscheck_keynum", vtype_stringptr, &prvscheck_keynum },
551 { "prvscheck_result", vtype_stringptr, &prvscheck_result },
552 { "qualify_domain", vtype_stringptr, &qualify_domain_sender },
553 { "qualify_recipient", vtype_stringptr, &qualify_domain_recipient },
554 { "rcpt_count", vtype_int, &rcpt_count },
555 { "rcpt_defer_count", vtype_int, &rcpt_defer_count },
556 { "rcpt_fail_count", vtype_int, &rcpt_fail_count },
557 { "received_count", vtype_int, &received_count },
558 { "received_for", vtype_stringptr, &received_for },
559 { "received_ip_address", vtype_stringptr, &interface_address },
560 { "received_port", vtype_int, &interface_port },
561 { "received_protocol", vtype_stringptr, &received_protocol },
562 { "received_time", vtype_int, &received_time },
563 { "recipient_data", vtype_stringptr, &recipient_data },
564 { "recipient_verify_failure",vtype_stringptr,&recipient_verify_failure },
565 { "recipients", vtype_recipients, NULL },
566 { "recipients_count", vtype_int, &recipients_count },
567 #ifdef WITH_CONTENT_SCAN
568 { "regex_match_string", vtype_stringptr, &regex_match_string },
569 #endif
570 { "reply_address", vtype_reply, NULL },
571 { "return_path", vtype_stringptr, &return_path },
572 { "return_size_limit", vtype_int, &bounce_return_size_limit },
573 { "runrc", vtype_int, &runrc },
574 { "self_hostname", vtype_stringptr, &self_hostname },
575 { "sender_address", vtype_stringptr, &sender_address },
576 { "sender_address_data", vtype_stringptr, &sender_address_data },
577 { "sender_address_domain", vtype_domain, &sender_address },
578 { "sender_address_local_part", vtype_localpart, &sender_address },
579 { "sender_data", vtype_stringptr, &sender_data },
580 { "sender_fullhost", vtype_stringptr, &sender_fullhost },
581 { "sender_helo_name", vtype_stringptr, &sender_helo_name },
582 { "sender_host_address", vtype_stringptr, &sender_host_address },
583 { "sender_host_authenticated",vtype_stringptr, &sender_host_authenticated },
584 { "sender_host_dnssec", vtype_bool, &sender_host_dnssec },
585 { "sender_host_name", vtype_host_lookup, NULL },
586 { "sender_host_port", vtype_int, &sender_host_port },
587 { "sender_ident", vtype_stringptr, &sender_ident },
588 { "sender_rate", vtype_stringptr, &sender_rate },
589 { "sender_rate_limit", vtype_stringptr, &sender_rate_limit },
590 { "sender_rate_period", vtype_stringptr, &sender_rate_period },
591 { "sender_rcvhost", vtype_stringptr, &sender_rcvhost },
592 { "sender_verify_failure",vtype_stringptr, &sender_verify_failure },
593 { "sending_ip_address", vtype_stringptr, &sending_ip_address },
594 { "sending_port", vtype_int, &sending_port },
595 { "smtp_active_hostname", vtype_stringptr, &smtp_active_hostname },
596 { "smtp_command", vtype_stringptr, &smtp_cmd_buffer },
597 { "smtp_command_argument", vtype_stringptr, &smtp_cmd_argument },
598 { "smtp_count_at_connection_start", vtype_int, &smtp_accept_count },
599 { "smtp_notquit_reason", vtype_stringptr, &smtp_notquit_reason },
600 { "sn0", vtype_filter_int, &filter_sn[0] },
601 { "sn1", vtype_filter_int, &filter_sn[1] },
602 { "sn2", vtype_filter_int, &filter_sn[2] },
603 { "sn3", vtype_filter_int, &filter_sn[3] },
604 { "sn4", vtype_filter_int, &filter_sn[4] },
605 { "sn5", vtype_filter_int, &filter_sn[5] },
606 { "sn6", vtype_filter_int, &filter_sn[6] },
607 { "sn7", vtype_filter_int, &filter_sn[7] },
608 { "sn8", vtype_filter_int, &filter_sn[8] },
609 { "sn9", vtype_filter_int, &filter_sn[9] },
610 #ifdef WITH_CONTENT_SCAN
611 { "spam_bar", vtype_stringptr, &spam_bar },
612 { "spam_report", vtype_stringptr, &spam_report },
613 { "spam_score", vtype_stringptr, &spam_score },
614 { "spam_score_int", vtype_stringptr, &spam_score_int },
615 #endif
616 #ifdef EXPERIMENTAL_SPF
617 { "spf_guess", vtype_stringptr, &spf_guess },
618 { "spf_header_comment", vtype_stringptr, &spf_header_comment },
619 { "spf_received", vtype_stringptr, &spf_received },
620 { "spf_result", vtype_stringptr, &spf_result },
621 { "spf_smtp_comment", vtype_stringptr, &spf_smtp_comment },
622 #endif
623 { "spool_directory", vtype_stringptr, &spool_directory },
624 { "spool_inodes", vtype_pinodes, (void *)TRUE },
625 { "spool_space", vtype_pspace, (void *)TRUE },
626 #ifdef EXPERIMENTAL_SRS
627 { "srs_db_address", vtype_stringptr, &srs_db_address },
628 { "srs_db_key", vtype_stringptr, &srs_db_key },
629 { "srs_orig_recipient", vtype_stringptr, &srs_orig_recipient },
630 { "srs_orig_sender", vtype_stringptr, &srs_orig_sender },
631 { "srs_recipient", vtype_stringptr, &srs_recipient },
632 { "srs_status", vtype_stringptr, &srs_status },
633 #endif
634 { "thisaddress", vtype_stringptr, &filter_thisaddress },
635
636 /* The non-(in,out) variables are now deprecated */
637 { "tls_bits", vtype_int, &tls_in.bits },
638 { "tls_certificate_verified", vtype_int, &tls_in.certificate_verified },
639 { "tls_cipher", vtype_stringptr, &tls_in.cipher },
640
641 { "tls_in_bits", vtype_int, &tls_in.bits },
642 { "tls_in_certificate_verified", vtype_int, &tls_in.certificate_verified },
643 { "tls_in_cipher", vtype_stringptr, &tls_in.cipher },
644 { "tls_in_peerdn", vtype_stringptr, &tls_in.peerdn },
645 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
646 { "tls_in_sni", vtype_stringptr, &tls_in.sni },
647 #endif
648 { "tls_out_bits", vtype_int, &tls_out.bits },
649 { "tls_out_certificate_verified", vtype_int,&tls_out.certificate_verified },
650 { "tls_out_cipher", vtype_stringptr, &tls_out.cipher },
651 { "tls_out_peerdn", vtype_stringptr, &tls_out.peerdn },
652 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
653 { "tls_out_sni", vtype_stringptr, &tls_out.sni },
654 #endif
655
656 { "tls_peerdn", vtype_stringptr, &tls_in.peerdn }, /* mind the alphabetical order! */
657 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
658 { "tls_sni", vtype_stringptr, &tls_in.sni }, /* mind the alphabetical order! */
659 #endif
660
661 { "tod_bsdinbox", vtype_todbsdin, NULL },
662 { "tod_epoch", vtype_tode, NULL },
663 { "tod_epoch_l", vtype_todel, NULL },
664 { "tod_full", vtype_todf, NULL },
665 { "tod_log", vtype_todl, NULL },
666 { "tod_logfile", vtype_todlf, NULL },
667 { "tod_zone", vtype_todzone, NULL },
668 { "tod_zulu", vtype_todzulu, NULL },
669 { "value", vtype_stringptr, &lookup_value },
670 { "version_number", vtype_stringptr, &version_string },
671 { "warn_message_delay", vtype_stringptr, &warnmsg_delay },
672 { "warn_message_recipient",vtype_stringptr, &warnmsg_recipients },
673 { "warn_message_recipients",vtype_stringptr,&warnmsg_recipients },
674 { "warnmsg_delay", vtype_stringptr, &warnmsg_delay },
675 { "warnmsg_recipient", vtype_stringptr, &warnmsg_recipients },
676 { "warnmsg_recipients", vtype_stringptr, &warnmsg_recipients }
677 };
678
679 static int var_table_size = sizeof(var_table)/sizeof(var_entry);
680 static uschar var_buffer[256];
681 static BOOL malformed_header;
682
683 /* For textual hashes */
684
685 static const char *hashcodes = "abcdefghijklmnopqrtsuvwxyz"
686 "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
687 "0123456789";
688
689 enum { HMAC_MD5, HMAC_SHA1 };
690
691 /* For numeric hashes */
692
693 static unsigned int prime[] = {
694 2, 3, 5, 7, 11, 13, 17, 19, 23, 29,
695 31, 37, 41, 43, 47, 53, 59, 61, 67, 71,
696 73, 79, 83, 89, 97, 101, 103, 107, 109, 113};
697
698 /* For printing modes in symbolic form */
699
700 static uschar *mtable_normal[] =
701 { US"---", US"--x", US"-w-", US"-wx", US"r--", US"r-x", US"rw-", US"rwx" };
702
703 static uschar *mtable_setid[] =
704 { US"--S", US"--s", US"-wS", US"-ws", US"r-S", US"r-s", US"rwS", US"rws" };
705
706 static uschar *mtable_sticky[] =
707 { US"--T", US"--t", US"-wT", US"-wt", US"r-T", US"r-t", US"rwT", US"rwt" };
708
709
710
711 /*************************************************
712 * Tables for UTF-8 support *
713 *************************************************/
714
715 /* Table of the number of extra characters, indexed by the first character
716 masked with 0x3f. The highest number for a valid UTF-8 character is in fact
717 0x3d. */
718
719 static uschar utf8_table1[] = {
720 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
721 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
722 2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
723 3,3,3,3,3,3,3,3,4,4,4,4,5,5,5,5 };
724
725 /* These are the masks for the data bits in the first byte of a character,
726 indexed by the number of additional bytes. */
727
728 static int utf8_table2[] = { 0xff, 0x1f, 0x0f, 0x07, 0x03, 0x01};
729
730 /* Get the next UTF-8 character, advancing the pointer. */
731
732 #define GETUTF8INC(c, ptr) \
733 c = *ptr++; \
734 if ((c & 0xc0) == 0xc0) \
735 { \
736 int a = utf8_table1[c & 0x3f]; /* Number of additional bytes */ \
737 int s = 6*a; \
738 c = (c & utf8_table2[a]) << s; \
739 while (a-- > 0) \
740 { \
741 s -= 6; \
742 c |= (*ptr++ & 0x3f) << s; \
743 } \
744 }
745
746
747 /*************************************************
748 * Binary chop search on a table *
749 *************************************************/
750
751 /* This is used for matching expansion items and operators.
752
753 Arguments:
754 name the name that is being sought
755 table the table to search
756 table_size the number of items in the table
757
758 Returns: the offset in the table, or -1
759 */
760
761 static int
762 chop_match(uschar *name, uschar **table, int table_size)
763 {
764 uschar **bot = table;
765 uschar **top = table + table_size;
766
767 while (top > bot)
768 {
769 uschar **mid = bot + (top - bot)/2;
770 int c = Ustrcmp(name, *mid);
771 if (c == 0) return mid - table;
772 if (c > 0) bot = mid + 1; else top = mid;
773 }
774
775 return -1;
776 }
777
778
779
780 /*************************************************
781 * Check a condition string *
782 *************************************************/
783
784 /* This function is called to expand a string, and test the result for a "true"
785 or "false" value. Failure of the expansion yields FALSE; logged unless it was a
786 forced fail or lookup defer. All store used by the function can be released on
787 exit.
788
789 The actual false-value tests should be replicated for ECOND_BOOL_LAX.
790
791 Arguments:
792 condition the condition string
793 m1 text to be incorporated in panic error
794 m2 ditto
795
796 Returns: TRUE if condition is met, FALSE if not
797 */
798
799 BOOL
800 expand_check_condition(uschar *condition, uschar *m1, uschar *m2)
801 {
802 int rc;
803 void *reset_point = store_get(0);
804 uschar *ss = expand_string(condition);
805 if (ss == NULL)
806 {
807 if (!expand_string_forcedfail && !search_find_defer)
808 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand condition \"%s\" "
809 "for %s %s: %s", condition, m1, m2, expand_string_message);
810 return FALSE;
811 }
812 rc = ss[0] != 0 && Ustrcmp(ss, "0") != 0 && strcmpic(ss, US"no") != 0 &&
813 strcmpic(ss, US"false") != 0;
814 store_reset(reset_point);
815 return rc;
816 }
817
818
819
820
821 /*************************************************
822 * Pseudo-random number generation *
823 *************************************************/
824
825 /* Pseudo-random number generation. The result is not "expected" to be
826 cryptographically strong but not so weak that someone will shoot themselves
827 in the foot using it as a nonce in some email header scheme or whatever
828 weirdness they'll twist this into. The result should ideally handle fork().
829
830 However, if we're stuck unable to provide this, then we'll fall back to
831 appallingly bad randomness.
832
833 If SUPPORT_TLS is defined then this will not be used except as an emergency
834 fallback.
835
836 Arguments:
837 max range maximum
838 Returns a random number in range [0, max-1]
839 */
840
841 #ifdef SUPPORT_TLS
842 # define vaguely_random_number vaguely_random_number_fallback
843 #endif
844 int
845 vaguely_random_number(int max)
846 {
847 #ifdef SUPPORT_TLS
848 # undef vaguely_random_number
849 #endif
850 static pid_t pid = 0;
851 pid_t p2;
852 #if defined(HAVE_SRANDOM) && !defined(HAVE_SRANDOMDEV)
853 struct timeval tv;
854 #endif
855
856 p2 = getpid();
857 if (p2 != pid)
858 {
859 if (pid != 0)
860 {
861
862 #ifdef HAVE_ARC4RANDOM
863 /* cryptographically strong randomness, common on *BSD platforms, not
864 so much elsewhere. Alas. */
865 arc4random_stir();
866 #elif defined(HAVE_SRANDOM) || defined(HAVE_SRANDOMDEV)
867 #ifdef HAVE_SRANDOMDEV
868 /* uses random(4) for seeding */
869 srandomdev();
870 #else
871 gettimeofday(&tv, NULL);
872 srandom(tv.tv_sec | tv.tv_usec | getpid());
873 #endif
874 #else
875 /* Poor randomness and no seeding here */
876 #endif
877
878 }
879 pid = p2;
880 }
881
882 #ifdef HAVE_ARC4RANDOM
883 return arc4random() % max;
884 #elif defined(HAVE_SRANDOM) || defined(HAVE_SRANDOMDEV)
885 return random() % max;
886 #else
887 /* This one returns a 16-bit number, definitely not crypto-strong */
888 return random_number(max);
889 #endif
890 }
891
892
893
894
895 /*************************************************
896 * Pick out a name from a string *
897 *************************************************/
898
899 /* If the name is too long, it is silently truncated.
900
901 Arguments:
902 name points to a buffer into which to put the name
903 max is the length of the buffer
904 s points to the first alphabetic character of the name
905 extras chars other than alphanumerics to permit
906
907 Returns: pointer to the first character after the name
908
909 Note: The test for *s != 0 in the while loop is necessary because
910 Ustrchr() yields non-NULL if the character is zero (which is not something
911 I expected). */
912
913 static uschar *
914 read_name(uschar *name, int max, uschar *s, uschar *extras)
915 {
916 int ptr = 0;
917 while (*s != 0 && (isalnum(*s) || Ustrchr(extras, *s) != NULL))
918 {
919 if (ptr < max-1) name[ptr++] = *s;
920 s++;
921 }
922 name[ptr] = 0;
923 return s;
924 }
925
926
927
928 /*************************************************
929 * Pick out the rest of a header name *
930 *************************************************/
931
932 /* A variable name starting $header_ (or just $h_ for those who like
933 abbreviations) might not be the complete header name because headers can
934 contain any printing characters in their names, except ':'. This function is
935 called to read the rest of the name, chop h[eader]_ off the front, and put ':'
936 on the end, if the name was terminated by white space.
937
938 Arguments:
939 name points to a buffer in which the name read so far exists
940 max is the length of the buffer
941 s points to the first character after the name so far, i.e. the
942 first non-alphameric character after $header_xxxxx
943
944 Returns: a pointer to the first character after the header name
945 */
946
947 static uschar *
948 read_header_name(uschar *name, int max, uschar *s)
949 {
950 int prelen = Ustrchr(name, '_') - name + 1;
951 int ptr = Ustrlen(name) - prelen;
952 if (ptr > 0) memmove(name, name+prelen, ptr);
953 while (mac_isgraph(*s) && *s != ':')
954 {
955 if (ptr < max-1) name[ptr++] = *s;
956 s++;
957 }
958 if (*s == ':') s++;
959 name[ptr++] = ':';
960 name[ptr] = 0;
961 return s;
962 }
963
964
965
966 /*************************************************
967 * Pick out a number from a string *
968 *************************************************/
969
970 /* Arguments:
971 n points to an integer into which to put the number
972 s points to the first digit of the number
973
974 Returns: a pointer to the character after the last digit
975 */
976
977 static uschar *
978 read_number(int *n, uschar *s)
979 {
980 *n = 0;
981 while (isdigit(*s)) *n = *n * 10 + (*s++ - '0');
982 return s;
983 }
984
985
986
987 /*************************************************
988 * Extract keyed subfield from a string *
989 *************************************************/
990
991 /* The yield is in dynamic store; NULL means that the key was not found.
992
993 Arguments:
994 key points to the name of the key
995 s points to the string from which to extract the subfield
996
997 Returns: NULL if the subfield was not found, or
998 a pointer to the subfield's data
999 */
1000
1001 static uschar *
1002 expand_getkeyed(uschar *key, uschar *s)
1003 {
1004 int length = Ustrlen(key);
1005 while (isspace(*s)) s++;
1006
1007 /* Loop to search for the key */
1008
1009 while (*s != 0)
1010 {
1011 int dkeylength;
1012 uschar *data;
1013 uschar *dkey = s;
1014
1015 while (*s != 0 && *s != '=' && !isspace(*s)) s++;
1016 dkeylength = s - dkey;
1017 while (isspace(*s)) s++;
1018 if (*s == '=') while (isspace((*(++s))));
1019
1020 data = string_dequote(&s);
1021 if (length == dkeylength && strncmpic(key, dkey, length) == 0)
1022 return data;
1023
1024 while (isspace(*s)) s++;
1025 }
1026
1027 return NULL;
1028 }
1029
1030
1031
1032
1033 /*************************************************
1034 * Extract numbered subfield from string *
1035 *************************************************/
1036
1037 /* Extracts a numbered field from a string that is divided by tokens - for
1038 example a line from /etc/passwd is divided by colon characters. First field is
1039 numbered one. Negative arguments count from the right. Zero returns the whole
1040 string. Returns NULL if there are insufficient tokens in the string
1041
1042 ***WARNING***
1043 Modifies final argument - this is a dynamically generated string, so that's OK.
1044
1045 Arguments:
1046 field number of field to be extracted,
1047 first field = 1, whole string = 0, last field = -1
1048 separators characters that are used to break string into tokens
1049 s points to the string from which to extract the subfield
1050
1051 Returns: NULL if the field was not found,
1052 a pointer to the field's data inside s (modified to add 0)
1053 */
1054
1055 static uschar *
1056 expand_gettokened (int field, uschar *separators, uschar *s)
1057 {
1058 int sep = 1;
1059 int count;
1060 uschar *ss = s;
1061 uschar *fieldtext = NULL;
1062
1063 if (field == 0) return s;
1064
1065 /* Break the line up into fields in place; for field > 0 we stop when we have
1066 done the number of fields we want. For field < 0 we continue till the end of
1067 the string, counting the number of fields. */
1068
1069 count = (field > 0)? field : INT_MAX;
1070
1071 while (count-- > 0)
1072 {
1073 size_t len;
1074
1075 /* Previous field was the last one in the string. For a positive field
1076 number, this means there are not enough fields. For a negative field number,
1077 check that there are enough, and scan back to find the one that is wanted. */
1078
1079 if (sep == 0)
1080 {
1081 if (field > 0 || (-field) > (INT_MAX - count - 1)) return NULL;
1082 if ((-field) == (INT_MAX - count - 1)) return s;
1083 while (field++ < 0)
1084 {
1085 ss--;
1086 while (ss[-1] != 0) ss--;
1087 }
1088 fieldtext = ss;
1089 break;
1090 }
1091
1092 /* Previous field was not last in the string; save its start and put a
1093 zero at its end. */
1094
1095 fieldtext = ss;
1096 len = Ustrcspn(ss, separators);
1097 sep = ss[len];
1098 ss[len] = 0;
1099 ss += len + 1;
1100 }
1101
1102 return fieldtext;
1103 }
1104
1105
1106
1107 /*************************************************
1108 * Extract a substring from a string *
1109 *************************************************/
1110
1111 /* Perform the ${substr or ${length expansion operations.
1112
1113 Arguments:
1114 subject the input string
1115 value1 the offset from the start of the input string to the start of
1116 the output string; if negative, count from the right.
1117 value2 the length of the output string, or negative (-1) for unset
1118 if value1 is positive, unset means "all after"
1119 if value1 is negative, unset means "all before"
1120 len set to the length of the returned string
1121
1122 Returns: pointer to the output string, or NULL if there is an error
1123 */
1124
1125 static uschar *
1126 extract_substr(uschar *subject, int value1, int value2, int *len)
1127 {
1128 int sublen = Ustrlen(subject);
1129
1130 if (value1 < 0) /* count from right */
1131 {
1132 value1 += sublen;
1133
1134 /* If the position is before the start, skip to the start, and adjust the
1135 length. If the length ends up negative, the substring is null because nothing
1136 can precede. This falls out naturally when the length is unset, meaning "all
1137 to the left". */
1138
1139 if (value1 < 0)
1140 {
1141 value2 += value1;
1142 if (value2 < 0) value2 = 0;
1143 value1 = 0;
1144 }
1145
1146 /* Otherwise an unset length => characters before value1 */
1147
1148 else if (value2 < 0)
1149 {
1150 value2 = value1;
1151 value1 = 0;
1152 }
1153 }
1154
1155 /* For a non-negative offset, if the starting position is past the end of the
1156 string, the result will be the null string. Otherwise, an unset length means
1157 "rest"; just set it to the maximum - it will be cut down below if necessary. */
1158
1159 else
1160 {
1161 if (value1 > sublen)
1162 {
1163 value1 = sublen;
1164 value2 = 0;
1165 }
1166 else if (value2 < 0) value2 = sublen;
1167 }
1168
1169 /* Cut the length down to the maximum possible for the offset value, and get
1170 the required characters. */
1171
1172 if (value1 + value2 > sublen) value2 = sublen - value1;
1173 *len = value2;
1174 return subject + value1;
1175 }
1176
1177
1178
1179
1180 /*************************************************
1181 * Old-style hash of a string *
1182 *************************************************/
1183
1184 /* Perform the ${hash expansion operation.
1185
1186 Arguments:
1187 subject the input string (an expanded substring)
1188 value1 the length of the output string; if greater or equal to the
1189 length of the input string, the input string is returned
1190 value2 the number of hash characters to use, or 26 if negative
1191 len set to the length of the returned string
1192
1193 Returns: pointer to the output string, or NULL if there is an error
1194 */
1195
1196 static uschar *
1197 compute_hash(uschar *subject, int value1, int value2, int *len)
1198 {
1199 int sublen = Ustrlen(subject);
1200
1201 if (value2 < 0) value2 = 26;
1202 else if (value2 > Ustrlen(hashcodes))
1203 {
1204 expand_string_message =
1205 string_sprintf("hash count \"%d\" too big", value2);
1206 return NULL;
1207 }
1208
1209 /* Calculate the hash text. We know it is shorter than the original string, so
1210 can safely place it in subject[] (we know that subject is always itself an
1211 expanded substring). */
1212
1213 if (value1 < sublen)
1214 {
1215 int c;
1216 int i = 0;
1217 int j = value1;
1218 while ((c = (subject[j])) != 0)
1219 {
1220 int shift = (c + j++) & 7;
1221 subject[i] ^= (c << shift) | (c >> (8-shift));
1222 if (++i >= value1) i = 0;
1223 }
1224 for (i = 0; i < value1; i++)
1225 subject[i] = hashcodes[(subject[i]) % value2];
1226 }
1227 else value1 = sublen;
1228
1229 *len = value1;
1230 return subject;
1231 }
1232
1233
1234
1235
1236 /*************************************************
1237 * Numeric hash of a string *
1238 *************************************************/
1239
1240 /* Perform the ${nhash expansion operation. The first characters of the
1241 string are treated as most important, and get the highest prime numbers.
1242
1243 Arguments:
1244 subject the input string
1245 value1 the maximum value of the first part of the result
1246 value2 the maximum value of the second part of the result,
1247 or negative to produce only a one-part result
1248 len set to the length of the returned string
1249
1250 Returns: pointer to the output string, or NULL if there is an error.
1251 */
1252
1253 static uschar *
1254 compute_nhash (uschar *subject, int value1, int value2, int *len)
1255 {
1256 uschar *s = subject;
1257 int i = 0;
1258 unsigned long int total = 0; /* no overflow */
1259
1260 while (*s != 0)
1261 {
1262 if (i == 0) i = sizeof(prime)/sizeof(int) - 1;
1263 total += prime[i--] * (unsigned int)(*s++);
1264 }
1265
1266 /* If value2 is unset, just compute one number */
1267
1268 if (value2 < 0)
1269 {
1270 s = string_sprintf("%d", total % value1);
1271 }
1272
1273 /* Otherwise do a div/mod hash */
1274
1275 else
1276 {
1277 total = total % (value1 * value2);
1278 s = string_sprintf("%d/%d", total/value2, total % value2);
1279 }
1280
1281 *len = Ustrlen(s);
1282 return s;
1283 }
1284
1285
1286
1287
1288
1289 /*************************************************
1290 * Find the value of a header or headers *
1291 *************************************************/
1292
1293 /* Multiple instances of the same header get concatenated, and this function
1294 can also return a concatenation of all the header lines. When concatenating
1295 specific headers that contain lists of addresses, a comma is inserted between
1296 them. Otherwise we use a straight concatenation. Because some messages can have
1297 pathologically large number of lines, there is a limit on the length that is
1298 returned. Also, to avoid massive store use which would result from using
1299 string_cat() as it copies and extends strings, we do a preliminary pass to find
1300 out exactly how much store will be needed. On "normal" messages this will be
1301 pretty trivial.
1302
1303 Arguments:
1304 name the name of the header, without the leading $header_ or $h_,
1305 or NULL if a concatenation of all headers is required
1306 exists_only TRUE if called from a def: test; don't need to build a string;
1307 just return a string that is not "" and not "0" if the header
1308 exists
1309 newsize return the size of memory block that was obtained; may be NULL
1310 if exists_only is TRUE
1311 want_raw TRUE if called for $rh_ or $rheader_ variables; no processing,
1312 other than concatenating, will be done on the header. Also used
1313 for $message_headers_raw.
1314 charset name of charset to translate MIME words to; used only if
1315 want_raw is false; if NULL, no translation is done (this is
1316 used for $bh_ and $bheader_)
1317
1318 Returns: NULL if the header does not exist, else a pointer to a new
1319 store block
1320 */
1321
1322 static uschar *
1323 find_header(uschar *name, BOOL exists_only, int *newsize, BOOL want_raw,
1324 uschar *charset)
1325 {
1326 BOOL found = name == NULL;
1327 int comma = 0;
1328 int len = found? 0 : Ustrlen(name);
1329 int i;
1330 uschar *yield = NULL;
1331 uschar *ptr = NULL;
1332
1333 /* Loop for two passes - saves code repetition */
1334
1335 for (i = 0; i < 2; i++)
1336 {
1337 int size = 0;
1338 header_line *h;
1339
1340 for (h = header_list; size < header_insert_maxlen && h != NULL; h = h->next)
1341 {
1342 if (h->type != htype_old && h->text != NULL) /* NULL => Received: placeholder */
1343 {
1344 if (name == NULL || (len <= h->slen && strncmpic(name, h->text, len) == 0))
1345 {
1346 int ilen;
1347 uschar *t;
1348
1349 if (exists_only) return US"1"; /* don't need actual string */
1350 found = TRUE;
1351 t = h->text + len; /* text to insert */
1352 if (!want_raw) /* unless wanted raw, */
1353 while (isspace(*t)) t++; /* remove leading white space */
1354 ilen = h->slen - (t - h->text); /* length to insert */
1355
1356 /* Unless wanted raw, remove trailing whitespace, including the
1357 newline. */
1358
1359 if (!want_raw)
1360 while (ilen > 0 && isspace(t[ilen-1])) ilen--;
1361
1362 /* Set comma = 1 if handling a single header and it's one of those
1363 that contains an address list, except when asked for raw headers. Only
1364 need to do this once. */
1365
1366 if (!want_raw && name != NULL && comma == 0 &&
1367 Ustrchr("BCFRST", h->type) != NULL)
1368 comma = 1;
1369
1370 /* First pass - compute total store needed; second pass - compute
1371 total store used, including this header. */
1372
1373 size += ilen + comma + 1; /* +1 for the newline */
1374
1375 /* Second pass - concatentate the data, up to a maximum. Note that
1376 the loop stops when size hits the limit. */
1377
1378 if (i != 0)
1379 {
1380 if (size > header_insert_maxlen)
1381 {
1382 ilen -= size - header_insert_maxlen - 1;
1383 comma = 0;
1384 }
1385 Ustrncpy(ptr, t, ilen);
1386 ptr += ilen;
1387
1388 /* For a non-raw header, put in the comma if needed, then add
1389 back the newline we removed above, provided there was some text in
1390 the header. */
1391
1392 if (!want_raw && ilen > 0)
1393 {
1394 if (comma != 0) *ptr++ = ',';
1395 *ptr++ = '\n';
1396 }
1397 }
1398 }
1399 }
1400 }
1401
1402 /* At end of first pass, return NULL if no header found. Then truncate size
1403 if necessary, and get the buffer to hold the data, returning the buffer size.
1404 */
1405
1406 if (i == 0)
1407 {
1408 if (!found) return NULL;
1409 if (size > header_insert_maxlen) size = header_insert_maxlen;
1410 *newsize = size + 1;
1411 ptr = yield = store_get(*newsize);
1412 }
1413 }
1414
1415 /* That's all we do for raw header expansion. */
1416
1417 if (want_raw)
1418 {
1419 *ptr = 0;
1420 }
1421
1422 /* Otherwise, remove a final newline and a redundant added comma. Then we do
1423 RFC 2047 decoding, translating the charset if requested. The rfc2047_decode2()
1424 function can return an error with decoded data if the charset translation
1425 fails. If decoding fails, it returns NULL. */
1426
1427 else
1428 {
1429 uschar *decoded, *error;
1430 if (ptr > yield && ptr[-1] == '\n') ptr--;
1431 if (ptr > yield && comma != 0 && ptr[-1] == ',') ptr--;
1432 *ptr = 0;
1433 decoded = rfc2047_decode2(yield, check_rfc2047_length, charset, '?', NULL,
1434 newsize, &error);
1435 if (error != NULL)
1436 {
1437 DEBUG(D_any) debug_printf("*** error in RFC 2047 decoding: %s\n"
1438 " input was: %s\n", error, yield);
1439 }
1440 if (decoded != NULL) yield = decoded;
1441 }
1442
1443 return yield;
1444 }
1445
1446
1447
1448
1449 /*************************************************
1450 * Find value of a variable *
1451 *************************************************/
1452
1453 /* The table of variables is kept in alphabetic order, so we can search it
1454 using a binary chop. The "choplen" variable is nothing to do with the binary
1455 chop.
1456
1457 Arguments:
1458 name the name of the variable being sought
1459 exists_only TRUE if this is a def: test; passed on to find_header()
1460 skipping TRUE => skip any processing evaluation; this is not the same as
1461 exists_only because def: may test for values that are first
1462 evaluated here
1463 newsize pointer to an int which is initially zero; if the answer is in
1464 a new memory buffer, *newsize is set to its size
1465
1466 Returns: NULL if the variable does not exist, or
1467 a pointer to the variable's contents, or
1468 something non-NULL if exists_only is TRUE
1469 */
1470
1471 static uschar *
1472 find_variable(uschar *name, BOOL exists_only, BOOL skipping, int *newsize)
1473 {
1474 int first = 0;
1475 int last = var_table_size;
1476
1477 /* Handle ACL variables, whose names are of the form acl_cxxx or acl_mxxx.
1478 Originally, xxx had to be a number in the range 0-9 (later 0-19), but from
1479 release 4.64 onwards arbitrary names are permitted, as long as the first 5
1480 characters are acl_c or acl_m and the sixth is either a digit or an underscore
1481 (this gave backwards compatibility at the changeover). There may be built-in
1482 variables whose names start acl_ but they should never start in this way. This
1483 slightly messy specification is a consequence of the history, needless to say.
1484
1485 If an ACL variable does not exist, treat it as empty, unless strict_acl_vars is
1486 set, in which case give an error. */
1487
1488 if ((Ustrncmp(name, "acl_c", 5) == 0 || Ustrncmp(name, "acl_m", 5) == 0) &&
1489 !isalpha(name[5]))
1490 {
1491 tree_node *node =
1492 tree_search((name[4] == 'c')? acl_var_c : acl_var_m, name + 4);
1493 return (node == NULL)? (strict_acl_vars? NULL : US"") : node->data.ptr;
1494 }
1495
1496 /* Handle $auth<n> variables. */
1497
1498 if (Ustrncmp(name, "auth", 4) == 0)
1499 {
1500 uschar *endptr;
1501 int n = Ustrtoul(name + 4, &endptr, 10);
1502 if (*endptr == 0 && n != 0 && n <= AUTH_VARS)
1503 return (auth_vars[n-1] == NULL)? US"" : auth_vars[n-1];
1504 }
1505
1506 /* For all other variables, search the table */
1507
1508 while (last > first)
1509 {
1510 uschar *s, *domain;
1511 uschar **ss;
1512 int middle = (first + last)/2;
1513 int c = Ustrcmp(name, var_table[middle].name);
1514
1515 if (c > 0) { first = middle + 1; continue; }
1516 if (c < 0) { last = middle; continue; }
1517
1518 /* Found an existing variable. If in skipping state, the value isn't needed,
1519 and we want to avoid processing (such as looking up the host name). */
1520
1521 if (skipping) return US"";
1522
1523 switch (var_table[middle].type)
1524 {
1525 case vtype_filter_int:
1526 if (!filter_running) return NULL;
1527 /* Fall through */
1528 /* VVVVVVVVVVVV */
1529 case vtype_int:
1530 sprintf(CS var_buffer, "%d", *(int *)(var_table[middle].value)); /* Integer */
1531 return var_buffer;
1532
1533 case vtype_ino:
1534 sprintf(CS var_buffer, "%ld", (long int)(*(ino_t *)(var_table[middle].value))); /* Inode */
1535 return var_buffer;
1536
1537 case vtype_gid:
1538 sprintf(CS var_buffer, "%ld", (long int)(*(gid_t *)(var_table[middle].value))); /* gid */
1539 return var_buffer;
1540
1541 case vtype_uid:
1542 sprintf(CS var_buffer, "%ld", (long int)(*(uid_t *)(var_table[middle].value))); /* uid */
1543 return var_buffer;
1544
1545 case vtype_bool:
1546 sprintf(CS var_buffer, "%s", *(BOOL *)(var_table[middle].value) ? "yes" : "no"); /* bool */
1547 return var_buffer;
1548
1549 case vtype_stringptr: /* Pointer to string */
1550 s = *((uschar **)(var_table[middle].value));
1551 return (s == NULL)? US"" : s;
1552
1553 case vtype_pid:
1554 sprintf(CS var_buffer, "%d", (int)getpid()); /* pid */
1555 return var_buffer;
1556
1557 case vtype_load_avg:
1558 sprintf(CS var_buffer, "%d", OS_GETLOADAVG()); /* load_average */
1559 return var_buffer;
1560
1561 case vtype_host_lookup: /* Lookup if not done so */
1562 if (sender_host_name == NULL && sender_host_address != NULL &&
1563 !host_lookup_failed && host_name_lookup() == OK)
1564 host_build_sender_fullhost();
1565 return (sender_host_name == NULL)? US"" : sender_host_name;
1566
1567 case vtype_localpart: /* Get local part from address */
1568 s = *((uschar **)(var_table[middle].value));
1569 if (s == NULL) return US"";
1570 domain = Ustrrchr(s, '@');
1571 if (domain == NULL) return s;
1572 if (domain - s > sizeof(var_buffer) - 1)
1573 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "local part longer than " SIZE_T_FMT
1574 " in string expansion", sizeof(var_buffer));
1575 Ustrncpy(var_buffer, s, domain - s);
1576 var_buffer[domain - s] = 0;
1577 return var_buffer;
1578
1579 case vtype_domain: /* Get domain from address */
1580 s = *((uschar **)(var_table[middle].value));
1581 if (s == NULL) return US"";
1582 domain = Ustrrchr(s, '@');
1583 return (domain == NULL)? US"" : domain + 1;
1584
1585 case vtype_msgheaders:
1586 return find_header(NULL, exists_only, newsize, FALSE, NULL);
1587
1588 case vtype_msgheaders_raw:
1589 return find_header(NULL, exists_only, newsize, TRUE, NULL);
1590
1591 case vtype_msgbody: /* Pointer to msgbody string */
1592 case vtype_msgbody_end: /* Ditto, the end of the msg */
1593 ss = (uschar **)(var_table[middle].value);
1594 if (*ss == NULL && deliver_datafile >= 0) /* Read body when needed */
1595 {
1596 uschar *body;
1597 off_t start_offset = SPOOL_DATA_START_OFFSET;
1598 int len = message_body_visible;
1599 if (len > message_size) len = message_size;
1600 *ss = body = store_malloc(len+1);
1601 body[0] = 0;
1602 if (var_table[middle].type == vtype_msgbody_end)
1603 {
1604 struct stat statbuf;
1605 if (fstat(deliver_datafile, &statbuf) == 0)
1606 {
1607 start_offset = statbuf.st_size - len;
1608 if (start_offset < SPOOL_DATA_START_OFFSET)
1609 start_offset = SPOOL_DATA_START_OFFSET;
1610 }
1611 }
1612 lseek(deliver_datafile, start_offset, SEEK_SET);
1613 len = read(deliver_datafile, body, len);
1614 if (len > 0)
1615 {
1616 body[len] = 0;
1617 if (message_body_newlines) /* Separate loops for efficiency */
1618 {
1619 while (len > 0)
1620 { if (body[--len] == 0) body[len] = ' '; }
1621 }
1622 else
1623 {
1624 while (len > 0)
1625 { if (body[--len] == '\n' || body[len] == 0) body[len] = ' '; }
1626 }
1627 }
1628 }
1629 return (*ss == NULL)? US"" : *ss;
1630
1631 case vtype_todbsdin: /* BSD inbox time of day */
1632 return tod_stamp(tod_bsdin);
1633
1634 case vtype_tode: /* Unix epoch time of day */
1635 return tod_stamp(tod_epoch);
1636
1637 case vtype_todel: /* Unix epoch/usec time of day */
1638 return tod_stamp(tod_epoch_l);
1639
1640 case vtype_todf: /* Full time of day */
1641 return tod_stamp(tod_full);
1642
1643 case vtype_todl: /* Log format time of day */
1644 return tod_stamp(tod_log_bare); /* (without timezone) */
1645
1646 case vtype_todzone: /* Time zone offset only */
1647 return tod_stamp(tod_zone);
1648
1649 case vtype_todzulu: /* Zulu time */
1650 return tod_stamp(tod_zulu);
1651
1652 case vtype_todlf: /* Log file datestamp tod */
1653 return tod_stamp(tod_log_datestamp_daily);
1654
1655 case vtype_reply: /* Get reply address */
1656 s = find_header(US"reply-to:", exists_only, newsize, TRUE,
1657 headers_charset);
1658 if (s != NULL) while (isspace(*s)) s++;
1659 if (s == NULL || *s == 0)
1660 {
1661 *newsize = 0; /* For the *s==0 case */
1662 s = find_header(US"from:", exists_only, newsize, TRUE, headers_charset);
1663 }
1664 if (s != NULL)
1665 {
1666 uschar *t;
1667 while (isspace(*s)) s++;
1668 for (t = s; *t != 0; t++) if (*t == '\n') *t = ' ';
1669 while (t > s && isspace(t[-1])) t--;
1670 *t = 0;
1671 }
1672 return (s == NULL)? US"" : s;
1673
1674 /* A recipients list is available only during system message filtering,
1675 during ACL processing after DATA, and while expanding pipe commands
1676 generated from a system filter, but not elsewhere. */
1677
1678 case vtype_recipients:
1679 if (!enable_dollar_recipients) return NULL; else
1680 {
1681 int size = 128;
1682 int ptr = 0;
1683 int i;
1684 s = store_get(size);
1685 for (i = 0; i < recipients_count; i++)
1686 {
1687 if (i != 0) s = string_cat(s, &size, &ptr, US", ", 2);
1688 s = string_cat(s, &size, &ptr, recipients_list[i].address,
1689 Ustrlen(recipients_list[i].address));
1690 }
1691 s[ptr] = 0; /* string_cat() leaves room */
1692 }
1693 return s;
1694
1695 case vtype_pspace:
1696 {
1697 int inodes;
1698 sprintf(CS var_buffer, "%d",
1699 receive_statvfs(var_table[middle].value == (void *)TRUE, &inodes));
1700 }
1701 return var_buffer;
1702
1703 case vtype_pinodes:
1704 {
1705 int inodes;
1706 (void) receive_statvfs(var_table[middle].value == (void *)TRUE, &inodes);
1707 sprintf(CS var_buffer, "%d", inodes);
1708 }
1709 return var_buffer;
1710
1711 #ifndef DISABLE_DKIM
1712 case vtype_dkim:
1713 return dkim_exim_expand_query((int)(long)var_table[middle].value);
1714 #endif
1715
1716 }
1717 }
1718
1719 return NULL; /* Unknown variable name */
1720 }
1721
1722
1723
1724
1725 void
1726 modify_variable(uschar *name, void * value)
1727 {
1728 int first = 0;
1729 int last = var_table_size;
1730
1731 while (last > first)
1732 {
1733 int middle = (first + last)/2;
1734 int c = Ustrcmp(name, var_table[middle].name);
1735
1736 if (c > 0) { first = middle + 1; continue; }
1737 if (c < 0) { last = middle; continue; }
1738
1739 /* Found an existing variable; change the item it refers to */
1740 var_table[middle].value = value;
1741 return;
1742 }
1743 return; /* Unknown variable name, fail silently */
1744 }
1745
1746
1747
1748
1749
1750 /*************************************************
1751 * Read and expand substrings *
1752 *************************************************/
1753
1754 /* This function is called to read and expand argument substrings for various
1755 expansion items. Some have a minimum requirement that is less than the maximum;
1756 in these cases, the first non-present one is set to NULL.
1757
1758 Arguments:
1759 sub points to vector of pointers to set
1760 n maximum number of substrings
1761 m minimum required
1762 sptr points to current string pointer
1763 skipping the skipping flag
1764 check_end if TRUE, check for final '}'
1765 name name of item, for error message
1766
1767 Returns: 0 OK; string pointer updated
1768 1 curly bracketing error (too few arguments)
1769 2 too many arguments (only if check_end is set); message set
1770 3 other error (expansion failure)
1771 */
1772
1773 static int
1774 read_subs(uschar **sub, int n, int m, uschar **sptr, BOOL skipping,
1775 BOOL check_end, uschar *name)
1776 {
1777 int i;
1778 uschar *s = *sptr;
1779
1780 while (isspace(*s)) s++;
1781 for (i = 0; i < n; i++)
1782 {
1783 if (*s != '{')
1784 {
1785 if (i < m) return 1;
1786 sub[i] = NULL;
1787 break;
1788 }
1789 sub[i] = expand_string_internal(s+1, TRUE, &s, skipping, TRUE);
1790 if (sub[i] == NULL) return 3;
1791 if (*s++ != '}') return 1;
1792 while (isspace(*s)) s++;
1793 }
1794 if (check_end && *s++ != '}')
1795 {
1796 if (s[-1] == '{')
1797 {
1798 expand_string_message = string_sprintf("Too many arguments for \"%s\" "
1799 "(max is %d)", name, n);
1800 return 2;
1801 }
1802 return 1;
1803 }
1804
1805 *sptr = s;
1806 return 0;
1807 }
1808
1809
1810
1811
1812 /*************************************************
1813 * Elaborate message for bad variable *
1814 *************************************************/
1815
1816 /* For the "unknown variable" message, take a look at the variable's name, and
1817 give additional information about possible ACL variables. The extra information
1818 is added on to expand_string_message.
1819
1820 Argument: the name of the variable
1821 Returns: nothing
1822 */
1823
1824 static void
1825 check_variable_error_message(uschar *name)
1826 {
1827 if (Ustrncmp(name, "acl_", 4) == 0)
1828 expand_string_message = string_sprintf("%s (%s)", expand_string_message,
1829 (name[4] == 'c' || name[4] == 'm')?
1830 (isalpha(name[5])?
1831 US"6th character of a user-defined ACL variable must be a digit or underscore" :
1832 US"strict_acl_vars is set" /* Syntax is OK, it has to be this */
1833 ) :
1834 US"user-defined ACL variables must start acl_c or acl_m");
1835 }
1836
1837
1838
1839 /*
1840 Load args from sub array to globals, and call acl_check().
1841
1842 Returns: OK access is granted by an ACCEPT verb
1843 DISCARD access is granted by a DISCARD verb
1844 FAIL access is denied
1845 FAIL_DROP access is denied; drop the connection
1846 DEFER can't tell at the moment
1847 ERROR disaster
1848 */
1849 static int
1850 eval_acl(uschar ** sub, int nsub, uschar ** user_msgp)
1851 {
1852 int i;
1853 uschar *dummy_log_msg;
1854
1855 for (i = 1; i < nsub && sub[i]; i++)
1856 acl_arg[i-1] = sub[i];
1857 acl_narg = i-1;
1858 while (i < nsub)
1859 acl_arg[i++ - 1] = NULL;
1860
1861 DEBUG(D_expand)
1862 debug_printf("expanding: acl: %s arg: %s%s\n",
1863 sub[0],
1864 acl_narg>0 ? sub[1] : US"<none>",
1865 acl_narg>1 ? " +more" : "");
1866
1867 return acl_check(ACL_WHERE_EXPANSION, NULL, sub[0], user_msgp, &dummy_log_msg);
1868 }
1869
1870
1871
1872
1873 /*************************************************
1874 * Read and evaluate a condition *
1875 *************************************************/
1876
1877 /*
1878 Arguments:
1879 s points to the start of the condition text
1880 yield points to a BOOL to hold the result of the condition test;
1881 if NULL, we are just reading through a condition that is
1882 part of an "or" combination to check syntax, or in a state
1883 where the answer isn't required
1884
1885 Returns: a pointer to the first character after the condition, or
1886 NULL after an error
1887 */
1888
1889 static uschar *
1890 eval_condition(uschar *s, BOOL *yield)
1891 {
1892 BOOL testfor = TRUE;
1893 BOOL tempcond, combined_cond;
1894 BOOL *subcondptr;
1895 BOOL sub2_honour_dollar = TRUE;
1896 int i, rc, cond_type, roffset;
1897 int_eximarith_t num[2];
1898 struct stat statbuf;
1899 uschar name[256];
1900 uschar *sub[10];
1901
1902 const pcre *re;
1903 const uschar *rerror;
1904
1905 for (;;)
1906 {
1907 while (isspace(*s)) s++;
1908 if (*s == '!') { testfor = !testfor; s++; } else break;
1909 }
1910
1911 /* Numeric comparisons are symbolic */
1912
1913 if (*s == '=' || *s == '>' || *s == '<')
1914 {
1915 int p = 0;
1916 name[p++] = *s++;
1917 if (*s == '=')
1918 {
1919 name[p++] = '=';
1920 s++;
1921 }
1922 name[p] = 0;
1923 }
1924
1925 /* All other conditions are named */
1926
1927 else s = read_name(name, 256, s, US"_");
1928
1929 /* If we haven't read a name, it means some non-alpha character is first. */
1930
1931 if (name[0] == 0)
1932 {
1933 expand_string_message = string_sprintf("condition name expected, "
1934 "but found \"%.16s\"", s);
1935 return NULL;
1936 }
1937
1938 /* Find which condition we are dealing with, and switch on it */
1939
1940 cond_type = chop_match(name, cond_table, sizeof(cond_table)/sizeof(uschar *));
1941 switch(cond_type)
1942 {
1943 /* def: tests for a non-empty variable, or for the existence of a header. If
1944 yield == NULL we are in a skipping state, and don't care about the answer. */
1945
1946 case ECOND_DEF:
1947 if (*s != ':')
1948 {
1949 expand_string_message = US"\":\" expected after \"def\"";
1950 return NULL;
1951 }
1952
1953 s = read_name(name, 256, s+1, US"_");
1954
1955 /* Test for a header's existence. If the name contains a closing brace
1956 character, this may be a user error where the terminating colon has been
1957 omitted. Set a flag to adjust a subsequent error message in this case. */
1958
1959 if (Ustrncmp(name, "h_", 2) == 0 ||
1960 Ustrncmp(name, "rh_", 3) == 0 ||
1961 Ustrncmp(name, "bh_", 3) == 0 ||
1962 Ustrncmp(name, "header_", 7) == 0 ||
1963 Ustrncmp(name, "rheader_", 8) == 0 ||
1964 Ustrncmp(name, "bheader_", 8) == 0)
1965 {
1966 s = read_header_name(name, 256, s);
1967 if (Ustrchr(name, '}') != NULL) malformed_header = TRUE;
1968 if (yield != NULL) *yield =
1969 (find_header(name, TRUE, NULL, FALSE, NULL) != NULL) == testfor;
1970 }
1971
1972 /* Test for a variable's having a non-empty value. A non-existent variable
1973 causes an expansion failure. */
1974
1975 else
1976 {
1977 uschar *value = find_variable(name, TRUE, yield == NULL, NULL);
1978 if (value == NULL)
1979 {
1980 expand_string_message = (name[0] == 0)?
1981 string_sprintf("variable name omitted after \"def:\"") :
1982 string_sprintf("unknown variable \"%s\" after \"def:\"", name);
1983 check_variable_error_message(name);
1984 return NULL;
1985 }
1986 if (yield != NULL) *yield = (value[0] != 0) == testfor;
1987 }
1988
1989 return s;
1990
1991
1992 /* first_delivery tests for first delivery attempt */
1993
1994 case ECOND_FIRST_DELIVERY:
1995 if (yield != NULL) *yield = deliver_firsttime == testfor;
1996 return s;
1997
1998
1999 /* queue_running tests for any process started by a queue runner */
2000
2001 case ECOND_QUEUE_RUNNING:
2002 if (yield != NULL) *yield = (queue_run_pid != (pid_t)0) == testfor;
2003 return s;
2004
2005
2006 /* exists: tests for file existence
2007 isip: tests for any IP address
2008 isip4: tests for an IPv4 address
2009 isip6: tests for an IPv6 address
2010 pam: does PAM authentication
2011 radius: does RADIUS authentication
2012 ldapauth: does LDAP authentication
2013 pwcheck: does Cyrus SASL pwcheck authentication
2014 */
2015
2016 case ECOND_EXISTS:
2017 case ECOND_ISIP:
2018 case ECOND_ISIP4:
2019 case ECOND_ISIP6:
2020 case ECOND_PAM:
2021 case ECOND_RADIUS:
2022 case ECOND_LDAPAUTH:
2023 case ECOND_PWCHECK:
2024
2025 while (isspace(*s)) s++;
2026 if (*s != '{') goto COND_FAILED_CURLY_START;
2027
2028 sub[0] = expand_string_internal(s+1, TRUE, &s, yield == NULL, TRUE);
2029 if (sub[0] == NULL) return NULL;
2030 if (*s++ != '}') goto COND_FAILED_CURLY_END;
2031
2032 if (yield == NULL) return s; /* No need to run the test if skipping */
2033
2034 switch(cond_type)
2035 {
2036 case ECOND_EXISTS:
2037 if ((expand_forbid & RDO_EXISTS) != 0)
2038 {
2039 expand_string_message = US"File existence tests are not permitted";
2040 return NULL;
2041 }
2042 *yield = (Ustat(sub[0], &statbuf) == 0) == testfor;
2043 break;
2044
2045 case ECOND_ISIP:
2046 case ECOND_ISIP4:
2047 case ECOND_ISIP6:
2048 rc = string_is_ip_address(sub[0], NULL);
2049 *yield = ((cond_type == ECOND_ISIP)? (rc != 0) :
2050 (cond_type == ECOND_ISIP4)? (rc == 4) : (rc == 6)) == testfor;
2051 break;
2052
2053 /* Various authentication tests - all optionally compiled */
2054
2055 case ECOND_PAM:
2056 #ifdef SUPPORT_PAM
2057 rc = auth_call_pam(sub[0], &expand_string_message);
2058 goto END_AUTH;
2059 #else
2060 goto COND_FAILED_NOT_COMPILED;
2061 #endif /* SUPPORT_PAM */
2062
2063 case ECOND_RADIUS:
2064 #ifdef RADIUS_CONFIG_FILE
2065 rc = auth_call_radius(sub[0], &expand_string_message);
2066 goto END_AUTH;
2067 #else
2068 goto COND_FAILED_NOT_COMPILED;
2069 #endif /* RADIUS_CONFIG_FILE */
2070
2071 case ECOND_LDAPAUTH:
2072 #ifdef LOOKUP_LDAP
2073 {
2074 /* Just to keep the interface the same */
2075 BOOL do_cache;
2076 int old_pool = store_pool;
2077 store_pool = POOL_SEARCH;
2078 rc = eldapauth_find((void *)(-1), NULL, sub[0], Ustrlen(sub[0]), NULL,
2079 &expand_string_message, &do_cache);
2080 store_pool = old_pool;
2081 }
2082 goto END_AUTH;
2083 #else
2084 goto COND_FAILED_NOT_COMPILED;
2085 #endif /* LOOKUP_LDAP */
2086
2087 case ECOND_PWCHECK:
2088 #ifdef CYRUS_PWCHECK_SOCKET
2089 rc = auth_call_pwcheck(sub[0], &expand_string_message);
2090 goto END_AUTH;
2091 #else
2092 goto COND_FAILED_NOT_COMPILED;
2093 #endif /* CYRUS_PWCHECK_SOCKET */
2094
2095 #if defined(SUPPORT_PAM) || defined(RADIUS_CONFIG_FILE) || \
2096 defined(LOOKUP_LDAP) || defined(CYRUS_PWCHECK_SOCKET)
2097 END_AUTH:
2098 if (rc == ERROR || rc == DEFER) return NULL;
2099 *yield = (rc == OK) == testfor;
2100 #endif
2101 }
2102 return s;
2103
2104
2105 /* call ACL (in a conditional context). Accept true, deny false.
2106 Defer is a forced-fail. Anything set by message= goes to $value.
2107 Up to ten parameters are used; we use the braces round the name+args
2108 like the saslauthd condition does, to permit a variable number of args.
2109 See also the expansion-item version EITEM_ACL and the traditional
2110 acl modifier ACLC_ACL.
2111 */
2112
2113 case ECOND_ACL:
2114 /* ${if acl {{name}{arg1}{arg2}...} {yes}{no}} */
2115 {
2116 uschar *nameargs;
2117 uschar *user_msg;
2118 BOOL cond = FALSE;
2119 int size = 0;
2120 int ptr = 0;
2121
2122 while (isspace(*s)) s++;
2123 if (*s++ != '{') goto COND_FAILED_CURLY_START;
2124
2125 switch(read_subs(sub, sizeof(sub)/sizeof(*sub), 1,
2126 &s, yield == NULL, TRUE, US"acl"))
2127 {
2128 case 1: expand_string_message = US"too few arguments or bracketing "
2129 "error for acl";
2130 case 2:
2131 case 3: return NULL;
2132 }
2133
2134 if (yield != NULL) switch(eval_acl(sub, sizeof(sub)/sizeof(*sub), &user_msg))
2135 {
2136 case OK:
2137 cond = TRUE;
2138 case FAIL:
2139 lookup_value = NULL;
2140 if (user_msg)
2141 {
2142 lookup_value = string_cat(NULL, &size, &ptr, user_msg, Ustrlen(user_msg));
2143 lookup_value[ptr] = '\0';
2144 }
2145 *yield = cond;
2146 break;
2147
2148 case DEFER:
2149 expand_string_forcedfail = TRUE;
2150 default:
2151 expand_string_message = string_sprintf("error from acl \"%s\"", sub[0]);
2152 return NULL;
2153 }
2154 return s;
2155 }
2156
2157
2158 /* saslauthd: does Cyrus saslauthd authentication. Four parameters are used:
2159
2160 ${if saslauthd {{username}{password}{service}{realm}} {yes}[no}}
2161
2162 However, the last two are optional. That is why the whole set is enclosed
2163 in their own set of braces. */
2164
2165 case ECOND_SASLAUTHD:
2166 #ifndef CYRUS_SASLAUTHD_SOCKET
2167 goto COND_FAILED_NOT_COMPILED;
2168 #else
2169 while (isspace(*s)) s++;
2170 if (*s++ != '{') goto COND_FAILED_CURLY_START;
2171 switch(read_subs(sub, 4, 2, &s, yield == NULL, TRUE, US"saslauthd"))
2172 {
2173 case 1: expand_string_message = US"too few arguments or bracketing "
2174 "error for saslauthd";
2175 case 2:
2176 case 3: return NULL;
2177 }
2178 if (sub[2] == NULL) sub[3] = NULL; /* realm if no service */
2179 if (yield != NULL)
2180 {
2181 int rc;
2182 rc = auth_call_saslauthd(sub[0], sub[1], sub[2], sub[3],
2183 &expand_string_message);
2184 if (rc == ERROR || rc == DEFER) return NULL;
2185 *yield = (rc == OK) == testfor;
2186 }
2187 return s;
2188 #endif /* CYRUS_SASLAUTHD_SOCKET */
2189
2190
2191 /* symbolic operators for numeric and string comparison, and a number of
2192 other operators, all requiring two arguments.
2193
2194 crypteq: encrypts plaintext and compares against an encrypted text,
2195 using crypt(), crypt16(), MD5 or SHA-1
2196 inlist/inlisti: checks if first argument is in the list of the second
2197 match: does a regular expression match and sets up the numerical
2198 variables if it succeeds
2199 match_address: matches in an address list
2200 match_domain: matches in a domain list
2201 match_ip: matches a host list that is restricted to IP addresses
2202 match_local_part: matches in a local part list
2203 */
2204
2205 case ECOND_MATCH_ADDRESS:
2206 case ECOND_MATCH_DOMAIN:
2207 case ECOND_MATCH_IP:
2208 case ECOND_MATCH_LOCAL_PART:
2209 #ifndef EXPAND_LISTMATCH_RHS
2210 sub2_honour_dollar = FALSE;
2211 #endif
2212 /* FALLTHROUGH */
2213
2214 case ECOND_CRYPTEQ:
2215 case ECOND_INLIST:
2216 case ECOND_INLISTI:
2217 case ECOND_MATCH:
2218
2219 case ECOND_NUM_L: /* Numerical comparisons */
2220 case ECOND_NUM_LE:
2221 case ECOND_NUM_E:
2222 case ECOND_NUM_EE:
2223 case ECOND_NUM_G:
2224 case ECOND_NUM_GE:
2225
2226 case ECOND_STR_LT: /* String comparisons */
2227 case ECOND_STR_LTI:
2228 case ECOND_STR_LE:
2229 case ECOND_STR_LEI:
2230 case ECOND_STR_EQ:
2231 case ECOND_STR_EQI:
2232 case ECOND_STR_GT:
2233 case ECOND_STR_GTI:
2234 case ECOND_STR_GE:
2235 case ECOND_STR_GEI:
2236
2237 for (i = 0; i < 2; i++)
2238 {
2239 /* Sometimes, we don't expand substrings; too many insecure configurations
2240 created using match_address{}{} and friends, where the second param
2241 includes information from untrustworthy sources. */
2242 BOOL honour_dollar = TRUE;
2243 if ((i > 0) && !sub2_honour_dollar)
2244 honour_dollar = FALSE;
2245
2246 while (isspace(*s)) s++;
2247 if (*s != '{')
2248 {
2249 if (i == 0) goto COND_FAILED_CURLY_START;
2250 expand_string_message = string_sprintf("missing 2nd string in {} "
2251 "after \"%s\"", name);
2252 return NULL;
2253 }
2254 sub[i] = expand_string_internal(s+1, TRUE, &s, yield == NULL,
2255 honour_dollar);
2256 if (sub[i] == NULL) return NULL;
2257 if (*s++ != '}') goto COND_FAILED_CURLY_END;
2258
2259 /* Convert to numerical if required; we know that the names of all the
2260 conditions that compare numbers do not start with a letter. This just saves
2261 checking for them individually. */
2262
2263 if (!isalpha(name[0]) && yield != NULL)
2264 {
2265 if (sub[i][0] == 0)
2266 {
2267 num[i] = 0;
2268 DEBUG(D_expand)
2269 debug_printf("empty string cast to zero for numerical comparison\n");
2270 }
2271 else
2272 {
2273 num[i] = expand_string_integer(sub[i], FALSE);
2274 if (expand_string_message != NULL) return NULL;
2275 }
2276 }
2277 }
2278
2279 /* Result not required */
2280
2281 if (yield == NULL) return s;
2282
2283 /* Do an appropriate comparison */
2284
2285 switch(cond_type)
2286 {
2287 case ECOND_NUM_E:
2288 case ECOND_NUM_EE:
2289 *yield = (num[0] == num[1]) == testfor;
2290 break;
2291
2292 case ECOND_NUM_G:
2293 *yield = (num[0] > num[1]) == testfor;
2294 break;
2295
2296 case ECOND_NUM_GE:
2297 *yield = (num[0] >= num[1]) == testfor;
2298 break;
2299
2300 case ECOND_NUM_L:
2301 *yield = (num[0] < num[1]) == testfor;
2302 break;
2303
2304 case ECOND_NUM_LE:
2305 *yield = (num[0] <= num[1]) == testfor;
2306 break;
2307
2308 case ECOND_STR_LT:
2309 *yield = (Ustrcmp(sub[0], sub[1]) < 0) == testfor;
2310 break;
2311
2312 case ECOND_STR_LTI:
2313 *yield = (strcmpic(sub[0], sub[1]) < 0) == testfor;
2314 break;
2315
2316 case ECOND_STR_LE:
2317 *yield = (Ustrcmp(sub[0], sub[1]) <= 0) == testfor;
2318 break;
2319
2320 case ECOND_STR_LEI:
2321 *yield = (strcmpic(sub[0], sub[1]) <= 0) == testfor;
2322 break;
2323
2324 case ECOND_STR_EQ:
2325 *yield = (Ustrcmp(sub[0], sub[1]) == 0) == testfor;
2326 break;
2327
2328 case ECOND_STR_EQI:
2329 *yield = (strcmpic(sub[0], sub[1]) == 0) == testfor;
2330 break;
2331
2332 case ECOND_STR_GT:
2333 *yield = (Ustrcmp(sub[0], sub[1]) > 0) == testfor;
2334 break;
2335
2336 case ECOND_STR_GTI:
2337 *yield = (strcmpic(sub[0], sub[1]) > 0) == testfor;
2338 break;
2339
2340 case ECOND_STR_GE:
2341 *yield = (Ustrcmp(sub[0], sub[1]) >= 0) == testfor;
2342 break;
2343
2344 case ECOND_STR_GEI:
2345 *yield = (strcmpic(sub[0], sub[1]) >= 0) == testfor;
2346 break;
2347
2348 case ECOND_MATCH: /* Regular expression match */
2349 re = pcre_compile(CS sub[1], PCRE_COPT, (const char **)&rerror, &roffset,
2350 NULL);
2351 if (re == NULL)
2352 {
2353 expand_string_message = string_sprintf("regular expression error in "
2354 "\"%s\": %s at offset %d", sub[1], rerror, roffset);
2355 return NULL;
2356 }
2357 *yield = regex_match_and_setup(re, sub[0], 0, -1) == testfor;
2358 break;
2359
2360 case ECOND_MATCH_ADDRESS: /* Match in an address list */
2361 rc = match_address_list(sub[0], TRUE, FALSE, &(sub[1]), NULL, -1, 0, NULL);
2362 goto MATCHED_SOMETHING;
2363
2364 case ECOND_MATCH_DOMAIN: /* Match in a domain list */
2365 rc = match_isinlist(sub[0], &(sub[1]), 0, &domainlist_anchor, NULL,
2366 MCL_DOMAIN + MCL_NOEXPAND, TRUE, NULL);
2367 goto MATCHED_SOMETHING;
2368
2369 case ECOND_MATCH_IP: /* Match IP address in a host list */
2370 if (sub[0][0] != 0 && string_is_ip_address(sub[0], NULL) == 0)
2371 {
2372 expand_string_message = string_sprintf("\"%s\" is not an IP address",
2373 sub[0]);
2374 return NULL;
2375 }
2376 else
2377 {
2378 unsigned int *nullcache = NULL;
2379 check_host_block cb;
2380
2381 cb.host_name = US"";
2382 cb.host_address = sub[0];
2383
2384 /* If the host address starts off ::ffff: it is an IPv6 address in
2385 IPv4-compatible mode. Find the IPv4 part for checking against IPv4
2386 addresses. */
2387
2388 cb.host_ipv4 = (Ustrncmp(cb.host_address, "::ffff:", 7) == 0)?
2389 cb.host_address + 7 : cb.host_address;
2390
2391 rc = match_check_list(
2392 &sub[1], /* the list */
2393 0, /* separator character */
2394 &hostlist_anchor, /* anchor pointer */
2395 &nullcache, /* cache pointer */
2396 check_host, /* function for testing */
2397 &cb, /* argument for function */
2398 MCL_HOST, /* type of check */
2399 sub[0], /* text for debugging */
2400 NULL); /* where to pass back data */
2401 }
2402 goto MATCHED_SOMETHING;
2403
2404 case ECOND_MATCH_LOCAL_PART:
2405 rc = match_isinlist(sub[0], &(sub[1]), 0, &localpartlist_anchor, NULL,
2406 MCL_LOCALPART + MCL_NOEXPAND, TRUE, NULL);
2407 /* Fall through */
2408 /* VVVVVVVVVVVV */
2409 MATCHED_SOMETHING:
2410 switch(rc)
2411 {
2412 case OK:
2413 *yield = testfor;
2414 break;
2415
2416 case FAIL:
2417 *yield = !testfor;
2418 break;
2419
2420 case DEFER:
2421 expand_string_message = string_sprintf("unable to complete match "
2422 "against \"%s\": %s", sub[1], search_error_message);
2423 return NULL;
2424 }
2425
2426 break;
2427
2428 /* Various "encrypted" comparisons. If the second string starts with
2429 "{" then an encryption type is given. Default to crypt() or crypt16()
2430 (build-time choice). */
2431
2432 case ECOND_CRYPTEQ:
2433 #ifndef SUPPORT_CRYPTEQ
2434 goto COND_FAILED_NOT_COMPILED;
2435 #else
2436 if (strncmpic(sub[1], US"{md5}", 5) == 0)
2437 {
2438 int sublen = Ustrlen(sub[1]+5);
2439 md5 base;
2440 uschar digest[16];
2441
2442 md5_start(&base);
2443 md5_end(&base, (uschar *)sub[0], Ustrlen(sub[0]), digest);
2444
2445 /* If the length that we are comparing against is 24, the MD5 digest
2446 is expressed as a base64 string. This is the way LDAP does it. However,
2447 some other software uses a straightforward hex representation. We assume
2448 this if the length is 32. Other lengths fail. */
2449
2450 if (sublen == 24)
2451 {
2452 uschar *coded = auth_b64encode((uschar *)digest, 16);
2453 DEBUG(D_auth) debug_printf("crypteq: using MD5+B64 hashing\n"
2454 " subject=%s\n crypted=%s\n", coded, sub[1]+5);
2455 *yield = (Ustrcmp(coded, sub[1]+5) == 0) == testfor;
2456 }
2457 else if (sublen == 32)
2458 {
2459 int i;
2460 uschar coded[36];
2461 for (i = 0; i < 16; i++) sprintf(CS (coded+2*i), "%02X", digest[i]);
2462 coded[32] = 0;
2463 DEBUG(D_auth) debug_printf("crypteq: using MD5+hex hashing\n"
2464 " subject=%s\n crypted=%s\n", coded, sub[1]+5);
2465 *yield = (strcmpic(coded, sub[1]+5) == 0) == testfor;
2466 }
2467 else
2468 {
2469 DEBUG(D_auth) debug_printf("crypteq: length for MD5 not 24 or 32: "
2470 "fail\n crypted=%s\n", sub[1]+5);
2471 *yield = !testfor;
2472 }
2473 }
2474
2475 else if (strncmpic(sub[1], US"{sha1}", 6) == 0)
2476 {
2477 int sublen = Ustrlen(sub[1]+6);
2478 sha1 base;
2479 uschar digest[20];
2480
2481 sha1_start(&base);
2482 sha1_end(&base, (uschar *)sub[0], Ustrlen(sub[0]), digest);
2483
2484 /* If the length that we are comparing against is 28, assume the SHA1
2485 digest is expressed as a base64 string. If the length is 40, assume a
2486 straightforward hex representation. Other lengths fail. */
2487
2488 if (sublen == 28)
2489 {
2490 uschar *coded = auth_b64encode((uschar *)digest, 20);
2491 DEBUG(D_auth) debug_printf("crypteq: using SHA1+B64 hashing\n"
2492 " subject=%s\n crypted=%s\n", coded, sub[1]+6);
2493 *yield = (Ustrcmp(coded, sub[1]+6) == 0) == testfor;
2494 }
2495 else if (sublen == 40)
2496 {
2497 int i;
2498 uschar coded[44];
2499 for (i = 0; i < 20; i++) sprintf(CS (coded+2*i), "%02X", digest[i]);
2500 coded[40] = 0;
2501 DEBUG(D_auth) debug_printf("crypteq: using SHA1+hex hashing\n"
2502 " subject=%s\n crypted=%s\n", coded, sub[1]+6);
2503 *yield = (strcmpic(coded, sub[1]+6) == 0) == testfor;
2504 }
2505 else
2506 {
2507 DEBUG(D_auth) debug_printf("crypteq: length for SHA-1 not 28 or 40: "
2508 "fail\n crypted=%s\n", sub[1]+6);
2509 *yield = !testfor;
2510 }
2511 }
2512
2513 else /* {crypt} or {crypt16} and non-{ at start */
2514 /* }-for-text-editors */
2515 {
2516 int which = 0;
2517 uschar *coded;
2518
2519 if (strncmpic(sub[1], US"{crypt}", 7) == 0)
2520 {
2521 sub[1] += 7;
2522 which = 1;
2523 }
2524 else if (strncmpic(sub[1], US"{crypt16}", 9) == 0)
2525 {
2526 sub[1] += 9;
2527 which = 2;
2528 }
2529 else if (sub[1][0] == '{')
2530 {
2531 expand_string_message = string_sprintf("unknown encryption mechanism "
2532 "in \"%s\"", sub[1]);
2533 return NULL;
2534 }
2535
2536 switch(which)
2537 {
2538 case 0: coded = US DEFAULT_CRYPT(CS sub[0], CS sub[1]); break;
2539 case 1: coded = US crypt(CS sub[0], CS sub[1]); break;
2540 default: coded = US crypt16(CS sub[0], CS sub[1]); break;
2541 }
2542
2543 #define STR(s) # s
2544 #define XSTR(s) STR(s)
2545 DEBUG(D_auth) debug_printf("crypteq: using %s()\n"
2546 " subject=%s\n crypted=%s\n",
2547 (which == 0)? XSTR(DEFAULT_CRYPT) : (which == 1)? "crypt" : "crypt16",
2548 coded, sub[1]);
2549 #undef STR
2550 #undef XSTR
2551
2552 /* If the encrypted string contains fewer than two characters (for the
2553 salt), force failure. Otherwise we get false positives: with an empty
2554 string the yield of crypt() is an empty string! */
2555
2556 *yield = (Ustrlen(sub[1]) < 2)? !testfor :
2557 (Ustrcmp(coded, sub[1]) == 0) == testfor;
2558 }
2559 break;
2560 #endif /* SUPPORT_CRYPTEQ */
2561
2562 case ECOND_INLIST:
2563 case ECOND_INLISTI:
2564 {
2565 int sep = 0;
2566 BOOL found = FALSE;
2567 uschar *save_iterate_item = iterate_item;
2568 int (*compare)(const uschar *, const uschar *);
2569
2570 if (cond_type == ECOND_INLISTI)
2571 compare = strcmpic;
2572 else
2573 compare = (int (*)(const uschar *, const uschar *)) strcmp;
2574
2575 while ((iterate_item = string_nextinlist(&sub[1], &sep, NULL, 0)) != NULL)
2576 if (compare(sub[0], iterate_item) == 0)
2577 {
2578 found = TRUE;
2579 break;
2580 }
2581 iterate_item = save_iterate_item;
2582 *yield = found;
2583 }
2584
2585 } /* Switch for comparison conditions */
2586
2587 return s; /* End of comparison conditions */
2588
2589
2590 /* and/or: computes logical and/or of several conditions */
2591
2592 case ECOND_AND:
2593 case ECOND_OR:
2594 subcondptr = (yield == NULL)? NULL : &tempcond;
2595 combined_cond = (cond_type == ECOND_AND);
2596
2597 while (isspace(*s)) s++;
2598 if (*s++ != '{') goto COND_FAILED_CURLY_START;
2599
2600 for (;;)
2601 {
2602 while (isspace(*s)) s++;
2603 if (*s == '}') break;
2604 if (*s != '{')
2605 {
2606 expand_string_message = string_sprintf("each subcondition "
2607 "inside an \"%s{...}\" condition must be in its own {}", name);
2608 return NULL;
2609 }
2610
2611 s = eval_condition(s+1, subcondptr);
2612 if (s == NULL)
2613 {
2614 expand_string_message = string_sprintf("%s inside \"%s{...}\" condition",
2615 expand_string_message, name);
2616 return NULL;
2617 }
2618 while (isspace(*s)) s++;
2619
2620 if (*s++ != '}')
2621 {
2622 expand_string_message = string_sprintf("missing } at end of condition "
2623 "inside \"%s\" group", name);
2624 return NULL;
2625 }
2626
2627 if (yield != NULL)
2628 {
2629 if (cond_type == ECOND_AND)
2630 {
2631 combined_cond &= tempcond;
2632 if (!combined_cond) subcondptr = NULL; /* once false, don't */
2633 } /* evaluate any more */
2634 else
2635 {
2636 combined_cond |= tempcond;
2637 if (combined_cond) subcondptr = NULL; /* once true, don't */
2638 } /* evaluate any more */
2639 }
2640 }
2641
2642 if (yield != NULL) *yield = (combined_cond == testfor);
2643 return ++s;
2644
2645
2646 /* forall/forany: iterates a condition with different values */
2647
2648 case ECOND_FORALL:
2649 case ECOND_FORANY:
2650 {
2651 int sep = 0;
2652 uschar *save_iterate_item = iterate_item;
2653
2654 while (isspace(*s)) s++;
2655 if (*s++ != '{') goto COND_FAILED_CURLY_START;
2656 sub[0] = expand_string_internal(s, TRUE, &s, (yield == NULL), TRUE);
2657 if (sub[0] == NULL) return NULL;
2658 if (*s++ != '}') goto COND_FAILED_CURLY_END;
2659
2660 while (isspace(*s)) s++;
2661 if (*s++ != '{') goto COND_FAILED_CURLY_START;
2662
2663 sub[1] = s;
2664
2665 /* Call eval_condition once, with result discarded (as if scanning a
2666 "false" part). This allows us to find the end of the condition, because if
2667 the list it empty, we won't actually evaluate the condition for real. */
2668
2669 s = eval_condition(sub[1], NULL);
2670 if (s == NULL)
2671 {
2672 expand_string_message = string_sprintf("%s inside \"%s\" condition",
2673 expand_string_message, name);
2674 return NULL;
2675 }
2676 while (isspace(*s)) s++;
2677
2678 if (*s++ != '}')
2679 {
2680 expand_string_message = string_sprintf("missing } at end of condition "
2681 "inside \"%s\"", name);
2682 return NULL;
2683 }
2684
2685 if (yield != NULL) *yield = !testfor;
2686 while ((iterate_item = string_nextinlist(&sub[0], &sep, NULL, 0)) != NULL)
2687 {
2688 DEBUG(D_expand) debug_printf("%s: $item = \"%s\"\n", name, iterate_item);
2689 if (eval_condition(sub[1], &tempcond) == NULL)
2690 {
2691 expand_string_message = string_sprintf("%s inside \"%s\" condition",
2692 expand_string_message, name);
2693 iterate_item = save_iterate_item;
2694 return NULL;
2695 }
2696 DEBUG(D_expand) debug_printf("%s: condition evaluated to %s\n", name,
2697 tempcond? "true":"false");
2698
2699 if (yield != NULL) *yield = (tempcond == testfor);
2700 if (tempcond == (cond_type == ECOND_FORANY)) break;
2701 }
2702
2703 iterate_item = save_iterate_item;
2704 return s;
2705 }
2706
2707
2708 /* The bool{} expansion condition maps a string to boolean.
2709 The values supported should match those supported by the ACL condition
2710 (acl.c, ACLC_CONDITION) so that we keep to a minimum the different ideas
2711 of true/false. Note that Router "condition" rules have a different
2712 interpretation, where general data can be used and only a few values
2713 map to FALSE.
2714 Note that readconf.c boolean matching, for boolean configuration options,
2715 only matches true/yes/false/no.
2716 The bool_lax{} condition matches the Router logic, which is much more
2717 liberal. */
2718 case ECOND_BOOL:
2719 case ECOND_BOOL_LAX:
2720 {
2721 uschar *sub_arg[1];
2722 uschar *t, *t2;
2723 uschar *ourname;
2724 size_t len;
2725 BOOL boolvalue = FALSE;
2726 while (isspace(*s)) s++;
2727 if (*s != '{') goto COND_FAILED_CURLY_START;
2728 ourname = cond_type == ECOND_BOOL_LAX ? US"bool_lax" : US"bool";
2729 switch(read_subs(sub_arg, 1, 1, &s, yield == NULL, FALSE, ourname))
2730 {
2731 case 1: expand_string_message = string_sprintf(
2732 "too few arguments or bracketing error for %s",
2733 ourname);
2734 /*FALLTHROUGH*/
2735 case 2:
2736 case 3: return NULL;
2737 }
2738 t = sub_arg[0];
2739 while (isspace(*t)) t++;
2740 len = Ustrlen(t);
2741 if (len)
2742 {
2743 /* trailing whitespace: seems like a good idea to ignore it too */
2744 t2 = t + len - 1;
2745 while (isspace(*t2)) t2--;
2746 if (t2 != (t + len))
2747 {
2748 *++t2 = '\0';
2749 len = t2 - t;
2750 }
2751 }
2752 DEBUG(D_expand)
2753 debug_printf("considering %s: %s\n", ourname, len ? t : US"<empty>");
2754 /* logic for the lax case from expand_check_condition(), which also does
2755 expands, and the logic is both short and stable enough that there should
2756 be no maintenance burden from replicating it. */
2757 if (len == 0)
2758 boolvalue = FALSE;
2759 else if (Ustrspn(t, "0123456789") == len)
2760 {
2761 boolvalue = (Uatoi(t) == 0) ? FALSE : TRUE;
2762 /* expand_check_condition only does a literal string "0" check */
2763 if ((cond_type == ECOND_BOOL_LAX) && (len > 1))
2764 boolvalue = TRUE;
2765 }
2766 else if (strcmpic(t, US"true") == 0 || strcmpic(t, US"yes") == 0)
2767 boolvalue = TRUE;
2768 else if (strcmpic(t, US"false") == 0 || strcmpic(t, US"no") == 0)
2769 boolvalue = FALSE;
2770 else if (cond_type == ECOND_BOOL_LAX)
2771 boolvalue = TRUE;
2772 else
2773 {
2774 expand_string_message = string_sprintf("unrecognised boolean "
2775 "value \"%s\"", t);
2776 return NULL;
2777 }
2778 if (yield != NULL) *yield = (boolvalue == testfor);
2779 return s;
2780 }
2781
2782 /* Unknown condition */
2783
2784 default:
2785 expand_string_message = string_sprintf("unknown condition \"%s\"", name);
2786 return NULL;
2787 } /* End switch on condition type */
2788
2789 /* Missing braces at start and end of data */
2790
2791 COND_FAILED_CURLY_START:
2792 expand_string_message = string_sprintf("missing { after \"%s\"", name);
2793 return NULL;
2794
2795 COND_FAILED_CURLY_END:
2796 expand_string_message = string_sprintf("missing } at end of \"%s\" condition",
2797 name);
2798 return NULL;
2799
2800 /* A condition requires code that is not compiled */
2801
2802 #if !defined(SUPPORT_PAM) || !defined(RADIUS_CONFIG_FILE) || \
2803 !defined(LOOKUP_LDAP) || !defined(CYRUS_PWCHECK_SOCKET) || \
2804 !defined(SUPPORT_CRYPTEQ) || !defined(CYRUS_SASLAUTHD_SOCKET)
2805 COND_FAILED_NOT_COMPILED:
2806 expand_string_message = string_sprintf("support for \"%s\" not compiled",
2807 name);
2808 return NULL;
2809 #endif
2810 }
2811
2812
2813
2814
2815 /*************************************************
2816 * Save numerical variables *
2817 *************************************************/
2818
2819 /* This function is called from items such as "if" that want to preserve and
2820 restore the numbered variables.
2821
2822 Arguments:
2823 save_expand_string points to an array of pointers to set
2824 save_expand_nlength points to an array of ints for the lengths
2825
2826 Returns: the value of expand max to save
2827 */
2828
2829 static int
2830 save_expand_strings(uschar **save_expand_nstring, int *save_expand_nlength)
2831 {
2832 int i;
2833 for (i = 0; i <= expand_nmax; i++)
2834 {
2835 save_expand_nstring[i] = expand_nstring[i];
2836 save_expand_nlength[i] = expand_nlength[i];
2837 }
2838 return expand_nmax;
2839 }
2840
2841
2842
2843 /*************************************************
2844 * Restore numerical variables *
2845 *************************************************/
2846
2847 /* This function restored saved values of numerical strings.
2848
2849 Arguments:
2850 save_expand_nmax the number of strings to restore
2851 save_expand_string points to an array of pointers
2852 save_expand_nlength points to an array of ints
2853
2854 Returns: nothing
2855 */
2856
2857 static void
2858 restore_expand_strings(int save_expand_nmax, uschar **save_expand_nstring,
2859 int *save_expand_nlength)
2860 {
2861 int i;
2862 expand_nmax = save_expand_nmax;
2863 for (i = 0; i <= expand_nmax; i++)
2864 {
2865 expand_nstring[i] = save_expand_nstring[i];
2866 expand_nlength[i] = save_expand_nlength[i];
2867 }
2868 }
2869
2870
2871
2872
2873
2874 /*************************************************
2875 * Handle yes/no substrings *
2876 *************************************************/
2877
2878 /* This function is used by ${if}, ${lookup} and ${extract} to handle the
2879 alternative substrings that depend on whether or not the condition was true,
2880 or the lookup or extraction succeeded. The substrings always have to be
2881 expanded, to check their syntax, but "skipping" is set when the result is not
2882 needed - this avoids unnecessary nested lookups.
2883
2884 Arguments:
2885 skipping TRUE if we were skipping when this item was reached
2886 yes TRUE if the first string is to be used, else use the second
2887 save_lookup a value to put back into lookup_value before the 2nd expansion
2888 sptr points to the input string pointer
2889 yieldptr points to the output string pointer
2890 sizeptr points to the output string size
2891 ptrptr points to the output string pointer
2892 type "lookup" or "if" or "extract" or "run", for error message
2893
2894 Returns: 0 OK; lookup_value has been reset to save_lookup
2895 1 expansion failed
2896 2 expansion failed because of bracketing error
2897 */
2898
2899 static int
2900 process_yesno(BOOL skipping, BOOL yes, uschar *save_lookup, uschar **sptr,
2901 uschar **yieldptr, int *sizeptr, int *ptrptr, uschar *type)
2902 {
2903 int rc = 0;
2904 uschar *s = *sptr; /* Local value */
2905 uschar *sub1, *sub2;
2906
2907 /* If there are no following strings, we substitute the contents of $value for
2908 lookups and for extractions in the success case. For the ${if item, the string
2909 "true" is substituted. In the fail case, nothing is substituted for all three
2910 items. */
2911
2912 while (isspace(*s)) s++;
2913 if (*s == '}')
2914 {
2915 if (type[0] == 'i')
2916 {
2917 if (yes) *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, US"true", 4);
2918 }
2919 else
2920 {
2921 if (yes && lookup_value != NULL)
2922 *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, lookup_value,
2923 Ustrlen(lookup_value));
2924 lookup_value = save_lookup;
2925 }
2926 s++;
2927 goto RETURN;
2928 }
2929
2930 /* The first following string must be braced. */
2931
2932 if (*s++ != '{') goto FAILED_CURLY;
2933
2934 /* Expand the first substring. Forced failures are noticed only if we actually
2935 want this string. Set skipping in the call in the fail case (this will always
2936 be the case if we were already skipping). */
2937
2938 sub1 = expand_string_internal(s, TRUE, &s, !yes, TRUE);
2939 if (sub1 == NULL && (yes || !expand_string_forcedfail)) goto FAILED;
2940 expand_string_forcedfail = FALSE;
2941 if (*s++ != '}') goto FAILED_CURLY;
2942
2943 /* If we want the first string, add it to the output */
2944
2945 if (yes)
2946 *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, sub1, Ustrlen(sub1));
2947
2948 /* If this is called from a lookup or an extract, we want to restore $value to
2949 what it was at the start of the item, so that it has this value during the
2950 second string expansion. For the call from "if" or "run" to this function,
2951 save_lookup is set to lookup_value, so that this statement does nothing. */
2952
2953 lookup_value = save_lookup;
2954
2955 /* There now follows either another substring, or "fail", or nothing. This
2956 time, forced failures are noticed only if we want the second string. We must
2957 set skipping in the nested call if we don't want this string, or if we were
2958 already skipping. */
2959
2960 while (isspace(*s)) s++;
2961 if (*s == '{')
2962 {
2963 sub2 = expand_string_internal(s+1, TRUE, &s, yes || skipping, TRUE);
2964 if (sub2 == NULL && (!yes || !expand_string_forcedfail)) goto FAILED;
2965 expand_string_forcedfail = FALSE;
2966 if (*s++ != '}') goto FAILED_CURLY;
2967
2968 /* If we want the second string, add it to the output */
2969
2970 if (!yes)
2971 *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, sub2, Ustrlen(sub2));
2972 }
2973
2974 /* If there is no second string, but the word "fail" is present when the use of
2975 the second string is wanted, set a flag indicating it was a forced failure
2976 rather than a syntactic error. Swallow the terminating } in case this is nested
2977 inside another lookup or if or extract. */
2978
2979 else if (*s != '}')
2980 {
2981 uschar name[256];
2982 s = read_name(name, sizeof(name), s, US"_");
2983 if (Ustrcmp(name, "fail") == 0)
2984 {
2985 if (!yes && !skipping)
2986 {
2987 while (isspace(*s)) s++;
2988 if (*s++ != '}') goto FAILED_CURLY;
2989 expand_string_message =
2990 string_sprintf("\"%s\" failed and \"fail\" requested", type);
2991 expand_string_forcedfail = TRUE;
2992 goto FAILED;
2993 }
2994 }
2995 else
2996 {
2997 expand_string_message =
2998 string_sprintf("syntax error in \"%s\" item - \"fail\" expected", type);
2999 goto FAILED;
3000 }
3001 }
3002
3003 /* All we have to do now is to check on the final closing brace. */
3004
3005 while (isspace(*s)) s++;
3006 if (*s++ == '}') goto RETURN;
3007
3008 /* Get here if there is a bracketing failure */
3009
3010 FAILED_CURLY:
3011 rc++;
3012
3013 /* Get here for other failures */
3014
3015 FAILED:
3016 rc++;
3017
3018 /* Update the input pointer value before returning */
3019
3020 RETURN:
3021 *sptr = s;
3022 return rc;
3023 }
3024
3025
3026
3027
3028 /*************************************************
3029 * Handle MD5 or SHA-1 computation for HMAC *
3030 *************************************************/
3031
3032 /* These are some wrapping functions that enable the HMAC code to be a bit
3033 cleaner. A good compiler will spot the tail recursion.
3034
3035 Arguments:
3036 type HMAC_MD5 or HMAC_SHA1
3037 remaining are as for the cryptographic hash functions
3038
3039 Returns: nothing
3040 */
3041
3042 static void
3043 chash_start(int type, void *base)
3044 {
3045 if (type == HMAC_MD5)
3046 md5_start((md5 *)base);
3047 else
3048 sha1_start((sha1 *)base);
3049 }
3050
3051 static void
3052 chash_mid(int type, void *base, uschar *string)
3053 {
3054 if (type == HMAC_MD5)
3055 md5_mid((md5 *)base, string);
3056 else
3057 sha1_mid((sha1 *)base, string);
3058 }
3059
3060 static void
3061 chash_end(int type, void *base, uschar *string, int length, uschar *digest)
3062 {
3063 if (type == HMAC_MD5)
3064 md5_end((md5 *)base, string, length, digest);
3065 else
3066 sha1_end((sha1 *)base, string, length, digest);
3067 }
3068
3069
3070
3071
3072
3073 /********************************************************
3074 * prvs: Get last three digits of days since Jan 1, 1970 *
3075 ********************************************************/
3076
3077 /* This is needed to implement the "prvs" BATV reverse
3078 path signing scheme
3079
3080 Argument: integer "days" offset to add or substract to
3081 or from the current number of days.
3082
3083 Returns: pointer to string containing the last three
3084 digits of the number of days since Jan 1, 1970,
3085 modified by the offset argument, NULL if there
3086 was an error in the conversion.
3087
3088 */
3089
3090 static uschar *
3091 prvs_daystamp(int day_offset)
3092 {
3093 uschar *days = store_get(32); /* Need at least 24 for cases */
3094 (void)string_format(days, 32, TIME_T_FMT, /* where TIME_T_FMT is %lld */
3095 (time(NULL) + day_offset*86400)/86400);
3096 return (Ustrlen(days) >= 3) ? &days[Ustrlen(days)-3] : US"100";
3097 }
3098
3099
3100
3101 /********************************************************
3102 * prvs: perform HMAC-SHA1 computation of prvs bits *
3103 ********************************************************/
3104
3105 /* This is needed to implement the "prvs" BATV reverse
3106 path signing scheme
3107
3108 Arguments:
3109 address RFC2821 Address to use
3110 key The key to use (must be less than 64 characters
3111 in size)
3112 key_num Single-digit key number to use. Defaults to
3113 '0' when NULL.
3114
3115 Returns: pointer to string containing the first three
3116 bytes of the final hash in hex format, NULL if
3117 there was an error in the process.
3118 */
3119
3120 static uschar *
3121 prvs_hmac_sha1(uschar *address, uschar *key, uschar *key_num, uschar *daystamp)
3122 {
3123 uschar *hash_source, *p;
3124 int size = 0,offset = 0,i;
3125 sha1 sha1_base;
3126 void *use_base = &sha1_base;
3127 uschar innerhash[20];
3128 uschar finalhash[20];
3129 uschar innerkey[64];
3130 uschar outerkey[64];
3131 uschar *finalhash_hex = store_get(40);
3132
3133 if (key_num == NULL)
3134 key_num = US"0";
3135
3136 if (Ustrlen(key) > 64)
3137 return NULL;
3138
3139 hash_source = string_cat(NULL,&size,&offset,key_num,1);
3140 string_cat(hash_source,&size,&offset,daystamp,3);
3141 string_cat(hash_source,&size,&offset,address,Ustrlen(address));
3142 hash_source[offset] = '\0';
3143
3144 DEBUG(D_expand) debug_printf("prvs: hash source is '%s'\n", hash_source);
3145
3146 memset(innerkey, 0x36, 64);
3147 memset(outerkey, 0x5c, 64);
3148
3149 for (i = 0; i < Ustrlen(key); i++)
3150 {
3151 innerkey[i] ^= key[i];
3152 outerkey[i] ^= key[i];
3153 }
3154
3155 chash_start(HMAC_SHA1, use_base);
3156 chash_mid(HMAC_SHA1, use_base, innerkey);
3157 chash_end(HMAC_SHA1, use_base, hash_source, offset, innerhash);
3158
3159 chash_start(HMAC_SHA1, use_base);
3160 chash_mid(HMAC_SHA1, use_base, outerkey);
3161 chash_end(HMAC_SHA1, use_base, innerhash, 20, finalhash);
3162
3163 p = finalhash_hex;
3164 for (i = 0; i < 3; i++)
3165 {
3166 *p++ = hex_digits[(finalhash[i] & 0xf0) >> 4];
3167 *p++ = hex_digits[finalhash[i] & 0x0f];
3168 }
3169 *p = '\0';
3170
3171 return finalhash_hex;
3172 }
3173
3174
3175
3176
3177 /*************************************************
3178 * Join a file onto the output string *
3179 *************************************************/
3180
3181 /* This is used for readfile and after a run expansion. It joins the contents
3182 of a file onto the output string, globally replacing newlines with a given
3183 string (optionally). The file is closed at the end.
3184
3185 Arguments:
3186 f the FILE
3187 yield pointer to the expandable string
3188 sizep pointer to the current size
3189 ptrp pointer to the current position
3190 eol newline replacement string, or NULL
3191
3192 Returns: new value of string pointer
3193 */
3194
3195 static uschar *
3196 cat_file(FILE *f, uschar *yield, int *sizep, int *ptrp, uschar *eol)
3197 {
3198 int eollen;
3199 uschar buffer[1024];
3200
3201 eollen = (eol == NULL)? 0 : Ustrlen(eol);
3202
3203 while (Ufgets(buffer, sizeof(buffer), f) != NULL)
3204 {
3205 int len = Ustrlen(buffer);
3206 if (eol != NULL && buffer[len-1] == '\n') len--;
3207 yield = string_cat(yield, sizep, ptrp, buffer, len);
3208 if (buffer[len] != 0)
3209 yield = string_cat(yield, sizep, ptrp, eol, eollen);
3210 }
3211
3212 if (yield != NULL) yield[*ptrp] = 0;
3213
3214 return yield;
3215 }
3216
3217
3218
3219
3220 /*************************************************
3221 * Evaluate numeric expression *
3222 *************************************************/
3223
3224 /* This is a set of mutually recursive functions that evaluate an arithmetic
3225 expression involving + - * / % & | ^ ~ << >> and parentheses. The only one of
3226 these functions that is called from elsewhere is eval_expr, whose interface is:
3227
3228 Arguments:
3229 sptr pointer to the pointer to the string - gets updated
3230 decimal TRUE if numbers are to be assumed decimal
3231 error pointer to where to put an error message - must be NULL on input
3232 endket TRUE if ')' must terminate - FALSE for external call
3233
3234 Returns: on success: the value of the expression, with *error still NULL
3235 on failure: an undefined value, with *error = a message
3236 */
3237
3238 static int_eximarith_t eval_op_or(uschar **, BOOL, uschar **);
3239
3240
3241 static int_eximarith_t
3242 eval_expr(uschar **sptr, BOOL decimal, uschar **error, BOOL endket)
3243 {
3244 uschar *s = *sptr;
3245 int_eximarith_t x = eval_op_or(&s, decimal, error);
3246 if (*error == NULL)
3247 {
3248 if (endket)
3249 {
3250 if (*s != ')')
3251 *error = US"expecting closing parenthesis";
3252 else
3253 while (isspace(*(++s)));
3254 }
3255 else if (*s != 0) *error = US"expecting operator";
3256 }
3257 *sptr = s;
3258 return x;
3259 }
3260
3261
3262 static int_eximarith_t
3263 eval_number(uschar **sptr, BOOL decimal, uschar **error)
3264 {
3265 register int c;
3266 int_eximarith_t n;
3267 uschar *s = *sptr;
3268 while (isspace(*s)) s++;
3269 c = *s;
3270 if (isdigit(c))
3271 {
3272 int count;
3273 (void)sscanf(CS s, (decimal? SC_EXIM_DEC "%n" : SC_EXIM_ARITH "%n"), &n, &count);
3274 s += count;
3275 switch (tolower(*s))
3276 {
3277 default: break;
3278 case 'k': n *= 1024; s++; break;
3279 case 'm': n *= 1024*1024; s++; break;
3280 case 'g': n *= 1024*1024*1024; s++; break;
3281 }
3282 while (isspace (*s)) s++;
3283 }
3284 else if (c == '(')
3285 {
3286 s++;
3287 n = eval_expr(&s, decimal, error, 1);
3288 }
3289 else
3290 {
3291 *error = US"expecting number or opening parenthesis";
3292 n = 0;
3293 }
3294 *sptr = s;
3295 return n;
3296 }
3297
3298
3299 static int_eximarith_t
3300 eval_op_unary(uschar **sptr, BOOL decimal, uschar **error)
3301 {
3302 uschar *s = *sptr;
3303 int_eximarith_t x;
3304 while (isspace(*s)) s++;
3305 if (*s == '+' || *s == '-' || *s == '~')
3306 {
3307 int op = *s++;
3308 x = eval_op_unary(&s, decimal, error);
3309 if (op == '-') x = -x;
3310 else if (op == '~') x = ~x;
3311 }
3312 else
3313 {
3314 x = eval_number(&s, decimal, error);
3315 }
3316 *sptr = s;
3317 return x;
3318 }
3319
3320
3321 static int_eximarith_t
3322 eval_op_mult(uschar **sptr, BOOL decimal, uschar **error)
3323 {
3324 uschar *s = *sptr;
3325 int_eximarith_t x = eval_op_unary(&s, decimal, error);
3326 if (*error == NULL)
3327 {
3328 while (*s == '*' || *s == '/' || *s == '%')
3329 {
3330 int op = *s++;
3331 int_eximarith_t y = eval_op_unary(&s, decimal, error);
3332 if (*error != NULL) break;
3333 /* SIGFPE both on div/mod by zero and on INT_MIN / -1, which would give
3334 * a value of INT_MAX+1. Note that INT_MIN * -1 gives INT_MIN for me, which
3335 * is a bug somewhere in [gcc 4.2.1, FreeBSD, amd64]. In fact, -N*-M where
3336 * -N*M is INT_MIN will yielf INT_MIN.
3337 * Since we don't support floating point, this is somewhat simpler.
3338 * Ideally, we'd return an error, but since we overflow for all other
3339 * arithmetic, consistency suggests otherwise, but what's the correct value
3340 * to use? There is none.
3341 * The C standard guarantees overflow for unsigned arithmetic but signed
3342 * overflow invokes undefined behaviour; in practice, this is overflow
3343 * except for converting INT_MIN to INT_MAX+1. We also can't guarantee
3344 * that long/longlong larger than int are available, or we could just work
3345 * with larger types. We should consider whether to guarantee 32bit eval
3346 * and 64-bit working variables, with errors returned. For now ...
3347 * So, the only SIGFPEs occur with a non-shrinking div/mod, thus -1; we
3348 * can just let the other invalid results occur otherwise, as they have
3349 * until now. For this one case, we can coerce.
3350 */
3351 if (y == -1 && x == LLONG_MIN && op != '*')
3352 {
3353 DEBUG(D_expand)
3354 debug_printf("Integer exception dodging: " PR_EXIM_ARITH "%c-1 coerced to " PR_EXIM_ARITH "\n",
3355 LLONG_MIN, op, LLONG_MAX);
3356 x = LLONG_MAX;
3357 continue;
3358 }
3359 if (op == '*')
3360 x *= y;
3361 else
3362 {
3363 if (y == 0)
3364 {
3365 *error = (op == '/') ? US"divide by zero" : US"modulo by zero";
3366 x = 0;
3367 break;
3368 }
3369 if (op == '/')
3370 x /= y;