6d5471f98e3ebffe7f0f75df9f18d297bda9e1d2
[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_string_func, /* value is string returned by given function */
371 vtype_todbsdin, /* value not used; generate BSD inbox tod */
372 vtype_tode, /* value not used; generate tod in epoch format */
373 vtype_todel, /* value not used; generate tod in epoch/usec format */
374 vtype_todf, /* value not used; generate full tod */
375 vtype_todl, /* value not used; generate log tod */
376 vtype_todlf, /* value not used; generate log file datestamp tod */
377 vtype_todzone, /* value not used; generate time zone only */
378 vtype_todzulu, /* value not used; generate zulu tod */
379 vtype_reply, /* value not used; get reply from headers */
380 vtype_pid, /* value not used; result is pid */
381 vtype_host_lookup, /* value not used; get host name */
382 vtype_load_avg, /* value not used; result is int from os_getloadavg */
383 vtype_pspace, /* partition space; value is T/F for spool/log */
384 vtype_pinodes /* partition inodes; value is T/F for spool/log */
385 #ifndef DISABLE_DKIM
386 ,vtype_dkim /* Lookup of value in DKIM signature */
387 #endif
388 };
389
390 static uschar * fn_recipients(void);
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 { "headers_added", vtype_string_func, &fn_hdrs_added },
475 { "home", vtype_stringptr, &deliver_home },
476 { "host", vtype_stringptr, &deliver_host },
477 { "host_address", vtype_stringptr, &deliver_host_address },
478 { "host_data", vtype_stringptr, &host_data },
479 { "host_lookup_deferred",vtype_int, &host_lookup_deferred },
480 { "host_lookup_failed", vtype_int, &host_lookup_failed },
481 { "inode", vtype_ino, &deliver_inode },
482 { "interface_address", vtype_stringptr, &interface_address },
483 { "interface_port", vtype_int, &interface_port },
484 { "item", vtype_stringptr, &iterate_item },
485 #ifdef LOOKUP_LDAP
486 { "ldap_dn", vtype_stringptr, &eldap_dn },
487 #endif
488 { "load_average", vtype_load_avg, NULL },
489 { "local_part", vtype_stringptr, &deliver_localpart },
490 { "local_part_data", vtype_stringptr, &deliver_localpart_data },
491 { "local_part_prefix", vtype_stringptr, &deliver_localpart_prefix },
492 { "local_part_suffix", vtype_stringptr, &deliver_localpart_suffix },
493 { "local_scan_data", vtype_stringptr, &local_scan_data },
494 { "local_user_gid", vtype_gid, &local_user_gid },
495 { "local_user_uid", vtype_uid, &local_user_uid },
496 { "localhost_number", vtype_int, &host_number },
497 { "log_inodes", vtype_pinodes, (void *)FALSE },
498 { "log_space", vtype_pspace, (void *)FALSE },
499 { "mailstore_basename", vtype_stringptr, &mailstore_basename },
500 #ifdef WITH_CONTENT_SCAN
501 { "malware_name", vtype_stringptr, &malware_name },
502 #endif
503 { "max_received_linelength", vtype_int, &max_received_linelength },
504 { "message_age", vtype_int, &message_age },
505 { "message_body", vtype_msgbody, &message_body },
506 { "message_body_end", vtype_msgbody_end, &message_body_end },
507 { "message_body_size", vtype_int, &message_body_size },
508 { "message_exim_id", vtype_stringptr, &message_id },
509 { "message_headers", vtype_msgheaders, NULL },
510 { "message_headers_raw", vtype_msgheaders_raw, NULL },
511 { "message_id", vtype_stringptr, &message_id },
512 { "message_linecount", vtype_int, &message_linecount },
513 { "message_size", vtype_int, &message_size },
514 #ifdef WITH_CONTENT_SCAN
515 { "mime_anomaly_level", vtype_int, &mime_anomaly_level },
516 { "mime_anomaly_text", vtype_stringptr, &mime_anomaly_text },
517 { "mime_boundary", vtype_stringptr, &mime_boundary },
518 { "mime_charset", vtype_stringptr, &mime_charset },
519 { "mime_content_description", vtype_stringptr, &mime_content_description },
520 { "mime_content_disposition", vtype_stringptr, &mime_content_disposition },
521 { "mime_content_id", vtype_stringptr, &mime_content_id },
522 { "mime_content_size", vtype_int, &mime_content_size },
523 { "mime_content_transfer_encoding",vtype_stringptr, &mime_content_transfer_encoding },
524 { "mime_content_type", vtype_stringptr, &mime_content_type },
525 { "mime_decoded_filename", vtype_stringptr, &mime_decoded_filename },
526 { "mime_filename", vtype_stringptr, &mime_filename },
527 { "mime_is_coverletter", vtype_int, &mime_is_coverletter },
528 { "mime_is_multipart", vtype_int, &mime_is_multipart },
529 { "mime_is_rfc822", vtype_int, &mime_is_rfc822 },
530 { "mime_part_count", vtype_int, &mime_part_count },
531 #endif
532 { "n0", vtype_filter_int, &filter_n[0] },
533 { "n1", vtype_filter_int, &filter_n[1] },
534 { "n2", vtype_filter_int, &filter_n[2] },
535 { "n3", vtype_filter_int, &filter_n[3] },
536 { "n4", vtype_filter_int, &filter_n[4] },
537 { "n5", vtype_filter_int, &filter_n[5] },
538 { "n6", vtype_filter_int, &filter_n[6] },
539 { "n7", vtype_filter_int, &filter_n[7] },
540 { "n8", vtype_filter_int, &filter_n[8] },
541 { "n9", vtype_filter_int, &filter_n[9] },
542 { "original_domain", vtype_stringptr, &deliver_domain_orig },
543 { "original_local_part", vtype_stringptr, &deliver_localpart_orig },
544 { "originator_gid", vtype_gid, &originator_gid },
545 { "originator_uid", vtype_uid, &originator_uid },
546 { "parent_domain", vtype_stringptr, &deliver_domain_parent },
547 { "parent_local_part", vtype_stringptr, &deliver_localpart_parent },
548 { "pid", vtype_pid, NULL },
549 { "primary_hostname", vtype_stringptr, &primary_hostname },
550 { "prvscheck_address", vtype_stringptr, &prvscheck_address },
551 { "prvscheck_keynum", vtype_stringptr, &prvscheck_keynum },
552 { "prvscheck_result", vtype_stringptr, &prvscheck_result },
553 { "qualify_domain", vtype_stringptr, &qualify_domain_sender },
554 { "qualify_recipient", vtype_stringptr, &qualify_domain_recipient },
555 { "rcpt_count", vtype_int, &rcpt_count },
556 { "rcpt_defer_count", vtype_int, &rcpt_defer_count },
557 { "rcpt_fail_count", vtype_int, &rcpt_fail_count },
558 { "received_count", vtype_int, &received_count },
559 { "received_for", vtype_stringptr, &received_for },
560 { "received_ip_address", vtype_stringptr, &interface_address },
561 { "received_port", vtype_int, &interface_port },
562 { "received_protocol", vtype_stringptr, &received_protocol },
563 { "received_time", vtype_int, &received_time },
564 { "recipient_data", vtype_stringptr, &recipient_data },
565 { "recipient_verify_failure",vtype_stringptr,&recipient_verify_failure },
566 { "recipients", vtype_string_func, &fn_recipients },
567 { "recipients_count", vtype_int, &recipients_count },
568 #ifdef WITH_CONTENT_SCAN
569 { "regex_match_string", vtype_stringptr, &regex_match_string },
570 #endif
571 { "reply_address", vtype_reply, NULL },
572 { "return_path", vtype_stringptr, &return_path },
573 { "return_size_limit", vtype_int, &bounce_return_size_limit },
574 { "runrc", vtype_int, &runrc },
575 { "self_hostname", vtype_stringptr, &self_hostname },
576 { "sender_address", vtype_stringptr, &sender_address },
577 { "sender_address_data", vtype_stringptr, &sender_address_data },
578 { "sender_address_domain", vtype_domain, &sender_address },
579 { "sender_address_local_part", vtype_localpart, &sender_address },
580 { "sender_data", vtype_stringptr, &sender_data },
581 { "sender_fullhost", vtype_stringptr, &sender_fullhost },
582 { "sender_helo_name", vtype_stringptr, &sender_helo_name },
583 { "sender_host_address", vtype_stringptr, &sender_host_address },
584 { "sender_host_authenticated",vtype_stringptr, &sender_host_authenticated },
585 { "sender_host_dnssec", vtype_bool, &sender_host_dnssec },
586 { "sender_host_name", vtype_host_lookup, NULL },
587 { "sender_host_port", vtype_int, &sender_host_port },
588 { "sender_ident", vtype_stringptr, &sender_ident },
589 { "sender_rate", vtype_stringptr, &sender_rate },
590 { "sender_rate_limit", vtype_stringptr, &sender_rate_limit },
591 { "sender_rate_period", vtype_stringptr, &sender_rate_period },
592 { "sender_rcvhost", vtype_stringptr, &sender_rcvhost },
593 { "sender_verify_failure",vtype_stringptr, &sender_verify_failure },
594 { "sending_ip_address", vtype_stringptr, &sending_ip_address },
595 { "sending_port", vtype_int, &sending_port },
596 { "smtp_active_hostname", vtype_stringptr, &smtp_active_hostname },
597 { "smtp_command", vtype_stringptr, &smtp_cmd_buffer },
598 { "smtp_command_argument", vtype_stringptr, &smtp_cmd_argument },
599 { "smtp_count_at_connection_start", vtype_int, &smtp_accept_count },
600 { "smtp_notquit_reason", vtype_stringptr, &smtp_notquit_reason },
601 { "sn0", vtype_filter_int, &filter_sn[0] },
602 { "sn1", vtype_filter_int, &filter_sn[1] },
603 { "sn2", vtype_filter_int, &filter_sn[2] },
604 { "sn3", vtype_filter_int, &filter_sn[3] },
605 { "sn4", vtype_filter_int, &filter_sn[4] },
606 { "sn5", vtype_filter_int, &filter_sn[5] },
607 { "sn6", vtype_filter_int, &filter_sn[6] },
608 { "sn7", vtype_filter_int, &filter_sn[7] },
609 { "sn8", vtype_filter_int, &filter_sn[8] },
610 { "sn9", vtype_filter_int, &filter_sn[9] },
611 #ifdef WITH_CONTENT_SCAN
612 { "spam_bar", vtype_stringptr, &spam_bar },
613 { "spam_report", vtype_stringptr, &spam_report },
614 { "spam_score", vtype_stringptr, &spam_score },
615 { "spam_score_int", vtype_stringptr, &spam_score_int },
616 #endif
617 #ifdef EXPERIMENTAL_SPF
618 { "spf_guess", vtype_stringptr, &spf_guess },
619 { "spf_header_comment", vtype_stringptr, &spf_header_comment },
620 { "spf_received", vtype_stringptr, &spf_received },
621 { "spf_result", vtype_stringptr, &spf_result },
622 { "spf_smtp_comment", vtype_stringptr, &spf_smtp_comment },
623 #endif
624 { "spool_directory", vtype_stringptr, &spool_directory },
625 { "spool_inodes", vtype_pinodes, (void *)TRUE },
626 { "spool_space", vtype_pspace, (void *)TRUE },
627 #ifdef EXPERIMENTAL_SRS
628 { "srs_db_address", vtype_stringptr, &srs_db_address },
629 { "srs_db_key", vtype_stringptr, &srs_db_key },
630 { "srs_orig_recipient", vtype_stringptr, &srs_orig_recipient },
631 { "srs_orig_sender", vtype_stringptr, &srs_orig_sender },
632 { "srs_recipient", vtype_stringptr, &srs_recipient },
633 { "srs_status", vtype_stringptr, &srs_status },
634 #endif
635 { "thisaddress", vtype_stringptr, &filter_thisaddress },
636
637 /* The non-(in,out) variables are now deprecated */
638 { "tls_bits", vtype_int, &tls_in.bits },
639 { "tls_certificate_verified", vtype_int, &tls_in.certificate_verified },
640 { "tls_cipher", vtype_stringptr, &tls_in.cipher },
641
642 { "tls_in_bits", vtype_int, &tls_in.bits },
643 { "tls_in_certificate_verified", vtype_int, &tls_in.certificate_verified },
644 { "tls_in_cipher", vtype_stringptr, &tls_in.cipher },
645 { "tls_in_peerdn", vtype_stringptr, &tls_in.peerdn },
646 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
647 { "tls_in_sni", vtype_stringptr, &tls_in.sni },
648 #endif
649 { "tls_out_bits", vtype_int, &tls_out.bits },
650 { "tls_out_certificate_verified", vtype_int,&tls_out.certificate_verified },
651 { "tls_out_cipher", vtype_stringptr, &tls_out.cipher },
652 { "tls_out_peerdn", vtype_stringptr, &tls_out.peerdn },
653 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
654 { "tls_out_sni", vtype_stringptr, &tls_out.sni },
655 #endif
656
657 { "tls_peerdn", vtype_stringptr, &tls_in.peerdn }, /* mind the alphabetical order! */
658 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
659 { "tls_sni", vtype_stringptr, &tls_in.sni }, /* mind the alphabetical order! */
660 #endif
661
662 { "tod_bsdinbox", vtype_todbsdin, NULL },
663 { "tod_epoch", vtype_tode, NULL },
664 { "tod_epoch_l", vtype_todel, NULL },
665 { "tod_full", vtype_todf, NULL },
666 { "tod_log", vtype_todl, NULL },
667 { "tod_logfile", vtype_todlf, NULL },
668 { "tod_zone", vtype_todzone, NULL },
669 { "tod_zulu", vtype_todzulu, NULL },
670 { "value", vtype_stringptr, &lookup_value },
671 { "version_number", vtype_stringptr, &version_string },
672 { "warn_message_delay", vtype_stringptr, &warnmsg_delay },
673 { "warn_message_recipient",vtype_stringptr, &warnmsg_recipients },
674 { "warn_message_recipients",vtype_stringptr,&warnmsg_recipients },
675 { "warnmsg_delay", vtype_stringptr, &warnmsg_delay },
676 { "warnmsg_recipient", vtype_stringptr, &warnmsg_recipients },
677 { "warnmsg_recipients", vtype_stringptr, &warnmsg_recipients }
678 };
679
680 static int var_table_size = sizeof(var_table)/sizeof(var_entry);
681 static uschar var_buffer[256];
682 static BOOL malformed_header;
683
684 /* For textual hashes */
685
686 static const char *hashcodes = "abcdefghijklmnopqrtsuvwxyz"
687 "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
688 "0123456789";
689
690 enum { HMAC_MD5, HMAC_SHA1 };
691
692 /* For numeric hashes */
693
694 static unsigned int prime[] = {
695 2, 3, 5, 7, 11, 13, 17, 19, 23, 29,
696 31, 37, 41, 43, 47, 53, 59, 61, 67, 71,
697 73, 79, 83, 89, 97, 101, 103, 107, 109, 113};
698
699 /* For printing modes in symbolic form */
700
701 static uschar *mtable_normal[] =
702 { US"---", US"--x", US"-w-", US"-wx", US"r--", US"r-x", US"rw-", US"rwx" };
703
704 static uschar *mtable_setid[] =
705 { US"--S", US"--s", US"-wS", US"-ws", US"r-S", US"r-s", US"rwS", US"rws" };
706
707 static uschar *mtable_sticky[] =
708 { US"--T", US"--t", US"-wT", US"-wt", US"r-T", US"r-t", US"rwT", US"rwt" };
709
710
711
712 /*************************************************
713 * Tables for UTF-8 support *
714 *************************************************/
715
716 /* Table of the number of extra characters, indexed by the first character
717 masked with 0x3f. The highest number for a valid UTF-8 character is in fact
718 0x3d. */
719
720 static uschar utf8_table1[] = {
721 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
722 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
723 2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
724 3,3,3,3,3,3,3,3,4,4,4,4,5,5,5,5 };
725
726 /* These are the masks for the data bits in the first byte of a character,
727 indexed by the number of additional bytes. */
728
729 static int utf8_table2[] = { 0xff, 0x1f, 0x0f, 0x07, 0x03, 0x01};
730
731 /* Get the next UTF-8 character, advancing the pointer. */
732
733 #define GETUTF8INC(c, ptr) \
734 c = *ptr++; \
735 if ((c & 0xc0) == 0xc0) \
736 { \
737 int a = utf8_table1[c & 0x3f]; /* Number of additional bytes */ \
738 int s = 6*a; \
739 c = (c & utf8_table2[a]) << s; \
740 while (a-- > 0) \
741 { \
742 s -= 6; \
743 c |= (*ptr++ & 0x3f) << s; \
744 } \
745 }
746
747
748 /*************************************************
749 * Binary chop search on a table *
750 *************************************************/
751
752 /* This is used for matching expansion items and operators.
753
754 Arguments:
755 name the name that is being sought
756 table the table to search
757 table_size the number of items in the table
758
759 Returns: the offset in the table, or -1
760 */
761
762 static int
763 chop_match(uschar *name, uschar **table, int table_size)
764 {
765 uschar **bot = table;
766 uschar **top = table + table_size;
767
768 while (top > bot)
769 {
770 uschar **mid = bot + (top - bot)/2;
771 int c = Ustrcmp(name, *mid);
772 if (c == 0) return mid - table;
773 if (c > 0) bot = mid + 1; else top = mid;
774 }
775
776 return -1;
777 }
778
779
780
781 /*************************************************
782 * Check a condition string *
783 *************************************************/
784
785 /* This function is called to expand a string, and test the result for a "true"
786 or "false" value. Failure of the expansion yields FALSE; logged unless it was a
787 forced fail or lookup defer.
788
789 We used to release all store used, but this is not not safe due
790 to ${dlfunc } and ${acl }. In any case expand_string_internal()
791 is reasonably careful to release what it can.
792
793 The actual false-value tests should be replicated for ECOND_BOOL_LAX.
794
795 Arguments:
796 condition the condition string
797 m1 text to be incorporated in panic error
798 m2 ditto
799
800 Returns: TRUE if condition is met, FALSE if not
801 */
802
803 BOOL
804 expand_check_condition(uschar *condition, uschar *m1, uschar *m2)
805 {
806 int rc;
807 uschar *ss = expand_string(condition);
808 if (ss == NULL)
809 {
810 if (!expand_string_forcedfail && !search_find_defer)
811 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand condition \"%s\" "
812 "for %s %s: %s", condition, m1, m2, expand_string_message);
813 return FALSE;
814 }
815 rc = ss[0] != 0 && Ustrcmp(ss, "0") != 0 && strcmpic(ss, US"no") != 0 &&
816 strcmpic(ss, US"false") != 0;
817 return rc;
818 }
819
820
821
822
823 /*************************************************
824 * Pseudo-random number generation *
825 *************************************************/
826
827 /* Pseudo-random number generation. The result is not "expected" to be
828 cryptographically strong but not so weak that someone will shoot themselves
829 in the foot using it as a nonce in some email header scheme or whatever
830 weirdness they'll twist this into. The result should ideally handle fork().
831
832 However, if we're stuck unable to provide this, then we'll fall back to
833 appallingly bad randomness.
834
835 If SUPPORT_TLS is defined then this will not be used except as an emergency
836 fallback.
837
838 Arguments:
839 max range maximum
840 Returns a random number in range [0, max-1]
841 */
842
843 #ifdef SUPPORT_TLS
844 # define vaguely_random_number vaguely_random_number_fallback
845 #endif
846 int
847 vaguely_random_number(int max)
848 {
849 #ifdef SUPPORT_TLS
850 # undef vaguely_random_number
851 #endif
852 static pid_t pid = 0;
853 pid_t p2;
854 #if defined(HAVE_SRANDOM) && !defined(HAVE_SRANDOMDEV)
855 struct timeval tv;
856 #endif
857
858 p2 = getpid();
859 if (p2 != pid)
860 {
861 if (pid != 0)
862 {
863
864 #ifdef HAVE_ARC4RANDOM
865 /* cryptographically strong randomness, common on *BSD platforms, not
866 so much elsewhere. Alas. */
867 arc4random_stir();
868 #elif defined(HAVE_SRANDOM) || defined(HAVE_SRANDOMDEV)
869 #ifdef HAVE_SRANDOMDEV
870 /* uses random(4) for seeding */
871 srandomdev();
872 #else
873 gettimeofday(&tv, NULL);
874 srandom(tv.tv_sec | tv.tv_usec | getpid());
875 #endif
876 #else
877 /* Poor randomness and no seeding here */
878 #endif
879
880 }
881 pid = p2;
882 }
883
884 #ifdef HAVE_ARC4RANDOM
885 return arc4random() % max;
886 #elif defined(HAVE_SRANDOM) || defined(HAVE_SRANDOMDEV)
887 return random() % max;
888 #else
889 /* This one returns a 16-bit number, definitely not crypto-strong */
890 return random_number(max);
891 #endif
892 }
893
894
895
896
897 /*************************************************
898 * Pick out a name from a string *
899 *************************************************/
900
901 /* If the name is too long, it is silently truncated.
902
903 Arguments:
904 name points to a buffer into which to put the name
905 max is the length of the buffer
906 s points to the first alphabetic character of the name
907 extras chars other than alphanumerics to permit
908
909 Returns: pointer to the first character after the name
910
911 Note: The test for *s != 0 in the while loop is necessary because
912 Ustrchr() yields non-NULL if the character is zero (which is not something
913 I expected). */
914
915 static uschar *
916 read_name(uschar *name, int max, uschar *s, uschar *extras)
917 {
918 int ptr = 0;
919 while (*s != 0 && (isalnum(*s) || Ustrchr(extras, *s) != NULL))
920 {
921 if (ptr < max-1) name[ptr++] = *s;
922 s++;
923 }
924 name[ptr] = 0;
925 return s;
926 }
927
928
929
930 /*************************************************
931 * Pick out the rest of a header name *
932 *************************************************/
933
934 /* A variable name starting $header_ (or just $h_ for those who like
935 abbreviations) might not be the complete header name because headers can
936 contain any printing characters in their names, except ':'. This function is
937 called to read the rest of the name, chop h[eader]_ off the front, and put ':'
938 on the end, if the name was terminated by white space.
939
940 Arguments:
941 name points to a buffer in which the name read so far exists
942 max is the length of the buffer
943 s points to the first character after the name so far, i.e. the
944 first non-alphameric character after $header_xxxxx
945
946 Returns: a pointer to the first character after the header name
947 */
948
949 static uschar *
950 read_header_name(uschar *name, int max, uschar *s)
951 {
952 int prelen = Ustrchr(name, '_') - name + 1;
953 int ptr = Ustrlen(name) - prelen;
954 if (ptr > 0) memmove(name, name+prelen, ptr);
955 while (mac_isgraph(*s) && *s != ':')
956 {
957 if (ptr < max-1) name[ptr++] = *s;
958 s++;
959 }
960 if (*s == ':') s++;
961 name[ptr++] = ':';
962 name[ptr] = 0;
963 return s;
964 }
965
966
967
968 /*************************************************
969 * Pick out a number from a string *
970 *************************************************/
971
972 /* Arguments:
973 n points to an integer into which to put the number
974 s points to the first digit of the number
975
976 Returns: a pointer to the character after the last digit
977 */
978
979 static uschar *
980 read_number(int *n, uschar *s)
981 {
982 *n = 0;
983 while (isdigit(*s)) *n = *n * 10 + (*s++ - '0');
984 return s;
985 }
986
987
988
989 /*************************************************
990 * Extract keyed subfield from a string *
991 *************************************************/
992
993 /* The yield is in dynamic store; NULL means that the key was not found.
994
995 Arguments:
996 key points to the name of the key
997 s points to the string from which to extract the subfield
998
999 Returns: NULL if the subfield was not found, or
1000 a pointer to the subfield's data
1001 */
1002
1003 static uschar *
1004 expand_getkeyed(uschar *key, uschar *s)
1005 {
1006 int length = Ustrlen(key);
1007 while (isspace(*s)) s++;
1008
1009 /* Loop to search for the key */
1010
1011 while (*s != 0)
1012 {
1013 int dkeylength;
1014 uschar *data;
1015 uschar *dkey = s;
1016
1017 while (*s != 0 && *s != '=' && !isspace(*s)) s++;
1018 dkeylength = s - dkey;
1019 while (isspace(*s)) s++;
1020 if (*s == '=') while (isspace((*(++s))));
1021
1022 data = string_dequote(&s);
1023 if (length == dkeylength && strncmpic(key, dkey, length) == 0)
1024 return data;
1025
1026 while (isspace(*s)) s++;
1027 }
1028
1029 return NULL;
1030 }
1031
1032
1033
1034
1035 /*************************************************
1036 * Extract numbered subfield from string *
1037 *************************************************/
1038
1039 /* Extracts a numbered field from a string that is divided by tokens - for
1040 example a line from /etc/passwd is divided by colon characters. First field is
1041 numbered one. Negative arguments count from the right. Zero returns the whole
1042 string. Returns NULL if there are insufficient tokens in the string
1043
1044 ***WARNING***
1045 Modifies final argument - this is a dynamically generated string, so that's OK.
1046
1047 Arguments:
1048 field number of field to be extracted,
1049 first field = 1, whole string = 0, last field = -1
1050 separators characters that are used to break string into tokens
1051 s points to the string from which to extract the subfield
1052
1053 Returns: NULL if the field was not found,
1054 a pointer to the field's data inside s (modified to add 0)
1055 */
1056
1057 static uschar *
1058 expand_gettokened (int field, uschar *separators, uschar *s)
1059 {
1060 int sep = 1;
1061 int count;
1062 uschar *ss = s;
1063 uschar *fieldtext = NULL;
1064
1065 if (field == 0) return s;
1066
1067 /* Break the line up into fields in place; for field > 0 we stop when we have
1068 done the number of fields we want. For field < 0 we continue till the end of
1069 the string, counting the number of fields. */
1070
1071 count = (field > 0)? field : INT_MAX;
1072
1073 while (count-- > 0)
1074 {
1075 size_t len;
1076
1077 /* Previous field was the last one in the string. For a positive field
1078 number, this means there are not enough fields. For a negative field number,
1079 check that there are enough, and scan back to find the one that is wanted. */
1080
1081 if (sep == 0)
1082 {
1083 if (field > 0 || (-field) > (INT_MAX - count - 1)) return NULL;
1084 if ((-field) == (INT_MAX - count - 1)) return s;
1085 while (field++ < 0)
1086 {
1087 ss--;
1088 while (ss[-1] != 0) ss--;
1089 }
1090 fieldtext = ss;
1091 break;
1092 }
1093
1094 /* Previous field was not last in the string; save its start and put a
1095 zero at its end. */
1096
1097 fieldtext = ss;
1098 len = Ustrcspn(ss, separators);
1099 sep = ss[len];
1100 ss[len] = 0;
1101 ss += len + 1;
1102 }
1103
1104 return fieldtext;
1105 }
1106
1107
1108
1109 /*************************************************
1110 * Extract a substring from a string *
1111 *************************************************/
1112
1113 /* Perform the ${substr or ${length expansion operations.
1114
1115 Arguments:
1116 subject the input string
1117 value1 the offset from the start of the input string to the start of
1118 the output string; if negative, count from the right.
1119 value2 the length of the output string, or negative (-1) for unset
1120 if value1 is positive, unset means "all after"
1121 if value1 is negative, unset means "all before"
1122 len set to the length of the returned string
1123
1124 Returns: pointer to the output string, or NULL if there is an error
1125 */
1126
1127 static uschar *
1128 extract_substr(uschar *subject, int value1, int value2, int *len)
1129 {
1130 int sublen = Ustrlen(subject);
1131
1132 if (value1 < 0) /* count from right */
1133 {
1134 value1 += sublen;
1135
1136 /* If the position is before the start, skip to the start, and adjust the
1137 length. If the length ends up negative, the substring is null because nothing
1138 can precede. This falls out naturally when the length is unset, meaning "all
1139 to the left". */
1140
1141 if (value1 < 0)
1142 {
1143 value2 += value1;
1144 if (value2 < 0) value2 = 0;
1145 value1 = 0;
1146 }
1147
1148 /* Otherwise an unset length => characters before value1 */
1149
1150 else if (value2 < 0)
1151 {
1152 value2 = value1;
1153 value1 = 0;
1154 }
1155 }
1156
1157 /* For a non-negative offset, if the starting position is past the end of the
1158 string, the result will be the null string. Otherwise, an unset length means
1159 "rest"; just set it to the maximum - it will be cut down below if necessary. */
1160
1161 else
1162 {
1163 if (value1 > sublen)
1164 {
1165 value1 = sublen;
1166 value2 = 0;
1167 }
1168 else if (value2 < 0) value2 = sublen;
1169 }
1170
1171 /* Cut the length down to the maximum possible for the offset value, and get
1172 the required characters. */
1173
1174 if (value1 + value2 > sublen) value2 = sublen - value1;
1175 *len = value2;
1176 return subject + value1;
1177 }
1178
1179
1180
1181
1182 /*************************************************
1183 * Old-style hash of a string *
1184 *************************************************/
1185
1186 /* Perform the ${hash expansion operation.
1187
1188 Arguments:
1189 subject the input string (an expanded substring)
1190 value1 the length of the output string; if greater or equal to the
1191 length of the input string, the input string is returned
1192 value2 the number of hash characters to use, or 26 if negative
1193 len set to the length of the returned string
1194
1195 Returns: pointer to the output string, or NULL if there is an error
1196 */
1197
1198 static uschar *
1199 compute_hash(uschar *subject, int value1, int value2, int *len)
1200 {
1201 int sublen = Ustrlen(subject);
1202
1203 if (value2 < 0) value2 = 26;
1204 else if (value2 > Ustrlen(hashcodes))
1205 {
1206 expand_string_message =
1207 string_sprintf("hash count \"%d\" too big", value2);
1208 return NULL;
1209 }
1210
1211 /* Calculate the hash text. We know it is shorter than the original string, so
1212 can safely place it in subject[] (we know that subject is always itself an
1213 expanded substring). */
1214
1215 if (value1 < sublen)
1216 {
1217 int c;
1218 int i = 0;
1219 int j = value1;
1220 while ((c = (subject[j])) != 0)
1221 {
1222 int shift = (c + j++) & 7;
1223 subject[i] ^= (c << shift) | (c >> (8-shift));
1224 if (++i >= value1) i = 0;
1225 }
1226 for (i = 0; i < value1; i++)
1227 subject[i] = hashcodes[(subject[i]) % value2];
1228 }
1229 else value1 = sublen;
1230
1231 *len = value1;
1232 return subject;
1233 }
1234
1235
1236
1237
1238 /*************************************************
1239 * Numeric hash of a string *
1240 *************************************************/
1241
1242 /* Perform the ${nhash expansion operation. The first characters of the
1243 string are treated as most important, and get the highest prime numbers.
1244
1245 Arguments:
1246 subject the input string
1247 value1 the maximum value of the first part of the result
1248 value2 the maximum value of the second part of the result,
1249 or negative to produce only a one-part result
1250 len set to the length of the returned string
1251
1252 Returns: pointer to the output string, or NULL if there is an error.
1253 */
1254
1255 static uschar *
1256 compute_nhash (uschar *subject, int value1, int value2, int *len)
1257 {
1258 uschar *s = subject;
1259 int i = 0;
1260 unsigned long int total = 0; /* no overflow */
1261
1262 while (*s != 0)
1263 {
1264 if (i == 0) i = sizeof(prime)/sizeof(int) - 1;
1265 total += prime[i--] * (unsigned int)(*s++);
1266 }
1267
1268 /* If value2 is unset, just compute one number */
1269
1270 if (value2 < 0)
1271 {
1272 s = string_sprintf("%d", total % value1);
1273 }
1274
1275 /* Otherwise do a div/mod hash */
1276
1277 else
1278 {
1279 total = total % (value1 * value2);
1280 s = string_sprintf("%d/%d", total/value2, total % value2);
1281 }
1282
1283 *len = Ustrlen(s);
1284 return s;
1285 }
1286
1287
1288
1289
1290
1291 /*************************************************
1292 * Find the value of a header or headers *
1293 *************************************************/
1294
1295 /* Multiple instances of the same header get concatenated, and this function
1296 can also return a concatenation of all the header lines. When concatenating
1297 specific headers that contain lists of addresses, a comma is inserted between
1298 them. Otherwise we use a straight concatenation. Because some messages can have
1299 pathologically large number of lines, there is a limit on the length that is
1300 returned. Also, to avoid massive store use which would result from using
1301 string_cat() as it copies and extends strings, we do a preliminary pass to find
1302 out exactly how much store will be needed. On "normal" messages this will be
1303 pretty trivial.
1304
1305 Arguments:
1306 name the name of the header, without the leading $header_ or $h_,
1307 or NULL if a concatenation of all headers is required
1308 exists_only TRUE if called from a def: test; don't need to build a string;
1309 just return a string that is not "" and not "0" if the header
1310 exists
1311 newsize return the size of memory block that was obtained; may be NULL
1312 if exists_only is TRUE
1313 want_raw TRUE if called for $rh_ or $rheader_ variables; no processing,
1314 other than concatenating, will be done on the header. Also used
1315 for $message_headers_raw.
1316 charset name of charset to translate MIME words to; used only if
1317 want_raw is false; if NULL, no translation is done (this is
1318 used for $bh_ and $bheader_)
1319
1320 Returns: NULL if the header does not exist, else a pointer to a new
1321 store block
1322 */
1323
1324 static uschar *
1325 find_header(uschar *name, BOOL exists_only, int *newsize, BOOL want_raw,
1326 uschar *charset)
1327 {
1328 BOOL found = name == NULL;
1329 int comma = 0;
1330 int len = found? 0 : Ustrlen(name);
1331 int i;
1332 uschar *yield = NULL;
1333 uschar *ptr = NULL;
1334
1335 /* Loop for two passes - saves code repetition */
1336
1337 for (i = 0; i < 2; i++)
1338 {
1339 int size = 0;
1340 header_line *h;
1341
1342 for (h = header_list; size < header_insert_maxlen && h != NULL; h = h->next)
1343 {
1344 if (h->type != htype_old && h->text != NULL) /* NULL => Received: placeholder */
1345 {
1346 if (name == NULL || (len <= h->slen && strncmpic(name, h->text, len) == 0))
1347 {
1348 int ilen;
1349 uschar *t;
1350
1351 if (exists_only) return US"1"; /* don't need actual string */
1352 found = TRUE;
1353 t = h->text + len; /* text to insert */
1354 if (!want_raw) /* unless wanted raw, */
1355 while (isspace(*t)) t++; /* remove leading white space */
1356 ilen = h->slen - (t - h->text); /* length to insert */
1357
1358 /* Unless wanted raw, remove trailing whitespace, including the
1359 newline. */
1360
1361 if (!want_raw)
1362 while (ilen > 0 && isspace(t[ilen-1])) ilen--;
1363
1364 /* Set comma = 1 if handling a single header and it's one of those
1365 that contains an address list, except when asked for raw headers. Only
1366 need to do this once. */
1367
1368 if (!want_raw && name != NULL && comma == 0 &&
1369 Ustrchr("BCFRST", h->type) != NULL)
1370 comma = 1;
1371
1372 /* First pass - compute total store needed; second pass - compute
1373 total store used, including this header. */
1374
1375 size += ilen + comma + 1; /* +1 for the newline */
1376
1377 /* Second pass - concatentate the data, up to a maximum. Note that
1378 the loop stops when size hits the limit. */
1379
1380 if (i != 0)
1381 {
1382 if (size > header_insert_maxlen)
1383 {
1384 ilen -= size - header_insert_maxlen - 1;
1385 comma = 0;
1386 }
1387 Ustrncpy(ptr, t, ilen);
1388 ptr += ilen;
1389
1390 /* For a non-raw header, put in the comma if needed, then add
1391 back the newline we removed above, provided there was some text in
1392 the header. */
1393
1394 if (!want_raw && ilen > 0)
1395 {
1396 if (comma != 0) *ptr++ = ',';
1397 *ptr++ = '\n';
1398 }
1399 }
1400 }
1401 }
1402 }
1403
1404 /* At end of first pass, return NULL if no header found. Then truncate size
1405 if necessary, and get the buffer to hold the data, returning the buffer size.
1406 */
1407
1408 if (i == 0)
1409 {
1410 if (!found) return NULL;
1411 if (size > header_insert_maxlen) size = header_insert_maxlen;
1412 *newsize = size + 1;
1413 ptr = yield = store_get(*newsize);
1414 }
1415 }
1416
1417 /* That's all we do for raw header expansion. */
1418
1419 if (want_raw)
1420 {
1421 *ptr = 0;
1422 }
1423
1424 /* Otherwise, remove a final newline and a redundant added comma. Then we do
1425 RFC 2047 decoding, translating the charset if requested. The rfc2047_decode2()
1426 function can return an error with decoded data if the charset translation
1427 fails. If decoding fails, it returns NULL. */
1428
1429 else
1430 {
1431 uschar *decoded, *error;
1432 if (ptr > yield && ptr[-1] == '\n') ptr--;
1433 if (ptr > yield && comma != 0 && ptr[-1] == ',') ptr--;
1434 *ptr = 0;
1435 decoded = rfc2047_decode2(yield, check_rfc2047_length, charset, '?', NULL,
1436 newsize, &error);
1437 if (error != NULL)
1438 {
1439 DEBUG(D_any) debug_printf("*** error in RFC 2047 decoding: %s\n"
1440 " input was: %s\n", error, yield);
1441 }
1442 if (decoded != NULL) yield = decoded;
1443 }
1444
1445 return yield;
1446 }
1447
1448
1449
1450
1451 /*************************************************
1452 * Return list of recipients *
1453 *************************************************/
1454 /* A recipients list is available only during system message filtering,
1455 during ACL processing after DATA, and while expanding pipe commands
1456 generated from a system filter, but not elsewhere. */
1457
1458 static uschar *
1459 fn_recipients(void)
1460 {
1461 if (!enable_dollar_recipients) return NULL; else
1462 {
1463 int size = 128;
1464 int ptr = 0;
1465 int i;
1466 uschar * s = store_get(size);
1467 for (i = 0; i < recipients_count; i++)
1468 {
1469 if (i != 0) s = string_cat(s, &size, &ptr, US", ", 2);
1470 s = string_cat(s, &size, &ptr, recipients_list[i].address,
1471 Ustrlen(recipients_list[i].address));
1472 }
1473 s[ptr] = 0; /* string_cat() leaves room */
1474 return s;
1475 }
1476 }
1477
1478
1479 /*************************************************
1480 * Find value of a variable *
1481 *************************************************/
1482
1483 /* The table of variables is kept in alphabetic order, so we can search it
1484 using a binary chop. The "choplen" variable is nothing to do with the binary
1485 chop.
1486
1487 Arguments:
1488 name the name of the variable being sought
1489 exists_only TRUE if this is a def: test; passed on to find_header()
1490 skipping TRUE => skip any processing evaluation; this is not the same as
1491 exists_only because def: may test for values that are first
1492 evaluated here
1493 newsize pointer to an int which is initially zero; if the answer is in
1494 a new memory buffer, *newsize is set to its size
1495
1496 Returns: NULL if the variable does not exist, or
1497 a pointer to the variable's contents, or
1498 something non-NULL if exists_only is TRUE
1499 */
1500
1501 static uschar *
1502 find_variable(uschar *name, BOOL exists_only, BOOL skipping, int *newsize)
1503 {
1504 int first = 0;
1505 int last = var_table_size;
1506
1507 /* Handle ACL variables, whose names are of the form acl_cxxx or acl_mxxx.
1508 Originally, xxx had to be a number in the range 0-9 (later 0-19), but from
1509 release 4.64 onwards arbitrary names are permitted, as long as the first 5
1510 characters are acl_c or acl_m and the sixth is either a digit or an underscore
1511 (this gave backwards compatibility at the changeover). There may be built-in
1512 variables whose names start acl_ but they should never start in this way. This
1513 slightly messy specification is a consequence of the history, needless to say.
1514
1515 If an ACL variable does not exist, treat it as empty, unless strict_acl_vars is
1516 set, in which case give an error. */
1517
1518 if ((Ustrncmp(name, "acl_c", 5) == 0 || Ustrncmp(name, "acl_m", 5) == 0) &&
1519 !isalpha(name[5]))
1520 {
1521 tree_node *node =
1522 tree_search((name[4] == 'c')? acl_var_c : acl_var_m, name + 4);
1523 return (node == NULL)? (strict_acl_vars? NULL : US"") : node->data.ptr;
1524 }
1525
1526 /* Handle $auth<n> variables. */
1527
1528 if (Ustrncmp(name, "auth", 4) == 0)
1529 {
1530 uschar *endptr;
1531 int n = Ustrtoul(name + 4, &endptr, 10);
1532 if (*endptr == 0 && n != 0 && n <= AUTH_VARS)
1533 return (auth_vars[n-1] == NULL)? US"" : auth_vars[n-1];
1534 }
1535
1536 /* For all other variables, search the table */
1537
1538 while (last > first)
1539 {
1540 uschar *s, *domain;
1541 uschar **ss;
1542 int middle = (first + last)/2;
1543 int c = Ustrcmp(name, var_table[middle].name);
1544
1545 if (c > 0) { first = middle + 1; continue; }
1546 if (c < 0) { last = middle; continue; }
1547
1548 /* Found an existing variable. If in skipping state, the value isn't needed,
1549 and we want to avoid processing (such as looking up the host name). */
1550
1551 if (skipping) return US"";
1552
1553 switch (var_table[middle].type)
1554 {
1555 case vtype_filter_int:
1556 if (!filter_running) return NULL;
1557 /* Fall through */
1558 /* VVVVVVVVVVVV */
1559 case vtype_int:
1560 sprintf(CS var_buffer, "%d", *(int *)(var_table[middle].value)); /* Integer */
1561 return var_buffer;
1562
1563 case vtype_ino:
1564 sprintf(CS var_buffer, "%ld", (long int)(*(ino_t *)(var_table[middle].value))); /* Inode */
1565 return var_buffer;
1566
1567 case vtype_gid:
1568 sprintf(CS var_buffer, "%ld", (long int)(*(gid_t *)(var_table[middle].value))); /* gid */
1569 return var_buffer;
1570
1571 case vtype_uid:
1572 sprintf(CS var_buffer, "%ld", (long int)(*(uid_t *)(var_table[middle].value))); /* uid */
1573 return var_buffer;
1574
1575 case vtype_bool:
1576 sprintf(CS var_buffer, "%s", *(BOOL *)(var_table[middle].value) ? "yes" : "no"); /* bool */
1577 return var_buffer;
1578
1579 case vtype_stringptr: /* Pointer to string */
1580 s = *((uschar **)(var_table[middle].value));
1581 return (s == NULL)? US"" : s;
1582
1583 case vtype_pid:
1584 sprintf(CS var_buffer, "%d", (int)getpid()); /* pid */
1585 return var_buffer;
1586
1587 case vtype_load_avg:
1588 sprintf(CS var_buffer, "%d", OS_GETLOADAVG()); /* load_average */
1589 return var_buffer;
1590
1591 case vtype_host_lookup: /* Lookup if not done so */
1592 if (sender_host_name == NULL && sender_host_address != NULL &&
1593 !host_lookup_failed && host_name_lookup() == OK)
1594 host_build_sender_fullhost();
1595 return (sender_host_name == NULL)? US"" : sender_host_name;
1596
1597 case vtype_localpart: /* Get local part from address */
1598 s = *((uschar **)(var_table[middle].value));
1599 if (s == NULL) return US"";
1600 domain = Ustrrchr(s, '@');
1601 if (domain == NULL) return s;
1602 if (domain - s > sizeof(var_buffer) - 1)
1603 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "local part longer than " SIZE_T_FMT
1604 " in string expansion", sizeof(var_buffer));
1605 Ustrncpy(var_buffer, s, domain - s);
1606 var_buffer[domain - s] = 0;
1607 return var_buffer;
1608
1609 case vtype_domain: /* Get domain from address */
1610 s = *((uschar **)(var_table[middle].value));
1611 if (s == NULL) return US"";
1612 domain = Ustrrchr(s, '@');
1613 return (domain == NULL)? US"" : domain + 1;
1614
1615 case vtype_msgheaders:
1616 return find_header(NULL, exists_only, newsize, FALSE, NULL);
1617
1618 case vtype_msgheaders_raw:
1619 return find_header(NULL, exists_only, newsize, TRUE, NULL);
1620
1621 case vtype_msgbody: /* Pointer to msgbody string */
1622 case vtype_msgbody_end: /* Ditto, the end of the msg */
1623 ss = (uschar **)(var_table[middle].value);
1624 if (*ss == NULL && deliver_datafile >= 0) /* Read body when needed */
1625 {
1626 uschar *body;
1627 off_t start_offset = SPOOL_DATA_START_OFFSET;
1628 int len = message_body_visible;
1629 if (len > message_size) len = message_size;
1630 *ss = body = store_malloc(len+1);
1631 body[0] = 0;
1632 if (var_table[middle].type == vtype_msgbody_end)
1633 {
1634 struct stat statbuf;
1635 if (fstat(deliver_datafile, &statbuf) == 0)
1636 {
1637 start_offset = statbuf.st_size - len;
1638 if (start_offset < SPOOL_DATA_START_OFFSET)
1639 start_offset = SPOOL_DATA_START_OFFSET;
1640 }
1641 }
1642 lseek(deliver_datafile, start_offset, SEEK_SET);
1643 len = read(deliver_datafile, body, len);
1644 if (len > 0)
1645 {
1646 body[len] = 0;
1647 if (message_body_newlines) /* Separate loops for efficiency */
1648 {
1649 while (len > 0)
1650 { if (body[--len] == 0) body[len] = ' '; }
1651 }
1652 else
1653 {
1654 while (len > 0)
1655 { if (body[--len] == '\n' || body[len] == 0) body[len] = ' '; }
1656 }
1657 }
1658 }
1659 return (*ss == NULL)? US"" : *ss;
1660
1661 case vtype_todbsdin: /* BSD inbox time of day */
1662 return tod_stamp(tod_bsdin);
1663
1664 case vtype_tode: /* Unix epoch time of day */
1665 return tod_stamp(tod_epoch);
1666
1667 case vtype_todel: /* Unix epoch/usec time of day */
1668 return tod_stamp(tod_epoch_l);
1669
1670 case vtype_todf: /* Full time of day */
1671 return tod_stamp(tod_full);
1672
1673 case vtype_todl: /* Log format time of day */
1674 return tod_stamp(tod_log_bare); /* (without timezone) */
1675
1676 case vtype_todzone: /* Time zone offset only */
1677 return tod_stamp(tod_zone);
1678
1679 case vtype_todzulu: /* Zulu time */
1680 return tod_stamp(tod_zulu);
1681
1682 case vtype_todlf: /* Log file datestamp tod */
1683 return tod_stamp(tod_log_datestamp_daily);
1684
1685 case vtype_reply: /* Get reply address */
1686 s = find_header(US"reply-to:", exists_only, newsize, TRUE,
1687 headers_charset);
1688 if (s != NULL) while (isspace(*s)) s++;
1689 if (s == NULL || *s == 0)
1690 {
1691 *newsize = 0; /* For the *s==0 case */
1692 s = find_header(US"from:", exists_only, newsize, TRUE, headers_charset);
1693 }
1694 if (s != NULL)
1695 {
1696 uschar *t;
1697 while (isspace(*s)) s++;
1698 for (t = s; *t != 0; t++) if (*t == '\n') *t = ' ';
1699 while (t > s && isspace(t[-1])) t--;
1700 *t = 0;
1701 }
1702 return (s == NULL)? US"" : s;
1703
1704 case vtype_string_func:
1705 {
1706 uschar * (*fn)() = var_table[middle].value;
1707 return fn();
1708 }
1709
1710 case vtype_pspace:
1711 {
1712 int inodes;
1713 sprintf(CS var_buffer, "%d",
1714 receive_statvfs(var_table[middle].value == (void *)TRUE, &inodes));
1715 }
1716 return var_buffer;
1717
1718 case vtype_pinodes:
1719 {
1720 int inodes;
1721 (void) receive_statvfs(var_table[middle].value == (void *)TRUE, &inodes);
1722 sprintf(CS var_buffer, "%d", inodes);
1723 }
1724 return var_buffer;
1725
1726 #ifndef DISABLE_DKIM
1727 case vtype_dkim:
1728 return dkim_exim_expand_query((int)(long)var_table[middle].value);
1729 #endif
1730
1731 }
1732 }
1733
1734 return NULL; /* Unknown variable name */
1735 }
1736
1737
1738
1739
1740 void
1741 modify_variable(uschar *name, void * value)
1742 {
1743 int first = 0;
1744 int last = var_table_size;
1745
1746 while (last > first)
1747 {
1748 int middle = (first + last)/2;
1749 int c = Ustrcmp(name, var_table[middle].name);
1750
1751 if (c > 0) { first = middle + 1; continue; }
1752 if (c < 0) { last = middle; continue; }
1753
1754 /* Found an existing variable; change the item it refers to */
1755 var_table[middle].value = value;
1756 return;
1757 }
1758 return; /* Unknown variable name, fail silently */
1759 }
1760
1761
1762
1763
1764
1765 /*************************************************
1766 * Read and expand substrings *
1767 *************************************************/
1768
1769 /* This function is called to read and expand argument substrings for various
1770 expansion items. Some have a minimum requirement that is less than the maximum;
1771 in these cases, the first non-present one is set to NULL.
1772
1773 Arguments:
1774 sub points to vector of pointers to set
1775 n maximum number of substrings
1776 m minimum required
1777 sptr points to current string pointer
1778 skipping the skipping flag
1779 check_end if TRUE, check for final '}'
1780 name name of item, for error message
1781
1782 Returns: 0 OK; string pointer updated
1783 1 curly bracketing error (too few arguments)
1784 2 too many arguments (only if check_end is set); message set
1785 3 other error (expansion failure)
1786 */
1787
1788 static int
1789 read_subs(uschar **sub, int n, int m, uschar **sptr, BOOL skipping,
1790 BOOL check_end, uschar *name)
1791 {
1792 int i;
1793 uschar *s = *sptr;
1794
1795 while (isspace(*s)) s++;
1796 for (i = 0; i < n; i++)
1797 {
1798 if (*s != '{')
1799 {
1800 if (i < m) return 1;
1801 sub[i] = NULL;
1802 break;
1803 }
1804 sub[i] = expand_string_internal(s+1, TRUE, &s, skipping, TRUE);
1805 if (sub[i] == NULL) return 3;
1806 if (*s++ != '}') return 1;
1807 while (isspace(*s)) s++;
1808 }
1809 if (check_end && *s++ != '}')
1810 {
1811 if (s[-1] == '{')
1812 {
1813 expand_string_message = string_sprintf("Too many arguments for \"%s\" "
1814 "(max is %d)", name, n);
1815 return 2;
1816 }
1817 return 1;
1818 }
1819
1820 *sptr = s;
1821 return 0;
1822 }
1823
1824
1825
1826
1827 /*************************************************
1828 * Elaborate message for bad variable *
1829 *************************************************/
1830
1831 /* For the "unknown variable" message, take a look at the variable's name, and
1832 give additional information about possible ACL variables. The extra information
1833 is added on to expand_string_message.
1834
1835 Argument: the name of the variable
1836 Returns: nothing
1837 */
1838
1839 static void
1840 check_variable_error_message(uschar *name)
1841 {
1842 if (Ustrncmp(name, "acl_", 4) == 0)
1843 expand_string_message = string_sprintf("%s (%s)", expand_string_message,
1844 (name[4] == 'c' || name[4] == 'm')?
1845 (isalpha(name[5])?
1846 US"6th character of a user-defined ACL variable must be a digit or underscore" :
1847 US"strict_acl_vars is set" /* Syntax is OK, it has to be this */
1848 ) :
1849 US"user-defined ACL variables must start acl_c or acl_m");
1850 }
1851
1852
1853
1854 /*
1855 Load args from sub array to globals, and call acl_check().
1856 Sub array will be corrupted on return.
1857
1858 Returns: OK access is granted by an ACCEPT verb
1859 DISCARD access is granted by a DISCARD verb
1860 FAIL access is denied
1861 FAIL_DROP access is denied; drop the connection
1862 DEFER can't tell at the moment
1863 ERROR disaster
1864 */
1865 static int
1866 eval_acl(uschar ** sub, int nsub, uschar ** user_msgp)
1867 {
1868 int i;
1869 uschar *tmp;
1870 int sav_narg = acl_narg;
1871 int ret;
1872
1873 if(--nsub > sizeof(acl_arg)/sizeof(*acl_arg)) nsub = sizeof(acl_arg)/sizeof(*acl_arg);
1874 for (i = 0; i < nsub && sub[i+1]; i++)
1875 {
1876 tmp = acl_arg[i];
1877 acl_arg[i] = sub[i+1]; /* place callers args in the globals */
1878 sub[i+1] = tmp; /* stash the old args using our caller's storage */
1879 }
1880 acl_narg = i;
1881 while (i < nsub)
1882 {
1883 sub[i+1] = acl_arg[i];
1884 acl_arg[i++] = NULL;
1885 }
1886
1887 DEBUG(D_expand)
1888 debug_printf("expanding: acl: %s arg: %s%s\n",
1889 sub[0],
1890 acl_narg>0 ? sub[1] : US"<none>",
1891 acl_narg>1 ? " +more" : "");
1892
1893 ret = acl_check(ACL_WHERE_EXPANSION, NULL, sub[0], user_msgp, &tmp);
1894
1895 for (i = 0; i < nsub; i++)
1896 acl_arg[i] = sub[i+1]; /* restore old args */
1897 acl_narg = sav_narg;
1898
1899 return ret;
1900 }
1901
1902
1903
1904
1905 /*************************************************
1906 * Read and evaluate a condition *
1907 *************************************************/
1908
1909 /*
1910 Arguments:
1911 s points to the start of the condition text
1912 yield points to a BOOL to hold the result of the condition test;
1913 if NULL, we are just reading through a condition that is
1914 part of an "or" combination to check syntax, or in a state
1915 where the answer isn't required
1916
1917 Returns: a pointer to the first character after the condition, or
1918 NULL after an error
1919 */
1920
1921 static uschar *
1922 eval_condition(uschar *s, BOOL *yield)
1923 {
1924 BOOL testfor = TRUE;
1925 BOOL tempcond, combined_cond;
1926 BOOL *subcondptr;
1927 BOOL sub2_honour_dollar = TRUE;
1928 int i, rc, cond_type, roffset;
1929 int_eximarith_t num[2];
1930 struct stat statbuf;
1931 uschar name[256];
1932 uschar *sub[10];
1933
1934 const pcre *re;
1935 const uschar *rerror;
1936
1937 for (;;)
1938 {
1939 while (isspace(*s)) s++;
1940 if (*s == '!') { testfor = !testfor; s++; } else break;
1941 }
1942
1943 /* Numeric comparisons are symbolic */
1944
1945 if (*s == '=' || *s == '>' || *s == '<')
1946 {
1947 int p = 0;
1948 name[p++] = *s++;
1949 if (*s == '=')
1950 {
1951 name[p++] = '=';
1952 s++;
1953 }
1954 name[p] = 0;
1955 }
1956
1957 /* All other conditions are named */
1958
1959 else s = read_name(name, 256, s, US"_");
1960
1961 /* If we haven't read a name, it means some non-alpha character is first. */
1962
1963 if (name[0] == 0)
1964 {
1965 expand_string_message = string_sprintf("condition name expected, "
1966 "but found \"%.16s\"", s);
1967 return NULL;
1968 }
1969
1970 /* Find which condition we are dealing with, and switch on it */
1971
1972 cond_type = chop_match(name, cond_table, sizeof(cond_table)/sizeof(uschar *));
1973 switch(cond_type)
1974 {
1975 /* def: tests for a non-empty variable, or for the existence of a header. If
1976 yield == NULL we are in a skipping state, and don't care about the answer. */
1977
1978 case ECOND_DEF:
1979 if (*s != ':')
1980 {
1981 expand_string_message = US"\":\" expected after \"def\"";
1982 return NULL;
1983 }
1984
1985 s = read_name(name, 256, s+1, US"_");
1986
1987 /* Test for a header's existence. If the name contains a closing brace
1988 character, this may be a user error where the terminating colon has been
1989 omitted. Set a flag to adjust a subsequent error message in this case. */
1990
1991 if (Ustrncmp(name, "h_", 2) == 0 ||
1992 Ustrncmp(name, "rh_", 3) == 0 ||
1993 Ustrncmp(name, "bh_", 3) == 0 ||
1994 Ustrncmp(name, "header_", 7) == 0 ||
1995 Ustrncmp(name, "rheader_", 8) == 0 ||
1996 Ustrncmp(name, "bheader_", 8) == 0)
1997 {
1998 s = read_header_name(name, 256, s);
1999 /* {-for-text-editors */
2000 if (Ustrchr(name, '}') != NULL) malformed_header = TRUE;
2001 if (yield != NULL) *yield =
2002 (find_header(name, TRUE, NULL, FALSE, NULL) != NULL) == testfor;
2003 }
2004
2005 /* Test for a variable's having a non-empty value. A non-existent variable
2006 causes an expansion failure. */
2007
2008 else
2009 {
2010 uschar *value = find_variable(name, TRUE, yield == NULL, NULL);
2011 if (value == NULL)
2012 {
2013 expand_string_message = (name[0] == 0)?
2014 string_sprintf("variable name omitted after \"def:\"") :
2015 string_sprintf("unknown variable \"%s\" after \"def:\"", name);
2016 check_variable_error_message(name);
2017 return NULL;
2018 }
2019 if (yield != NULL) *yield = (value[0] != 0) == testfor;
2020 }
2021
2022 return s;
2023
2024
2025 /* first_delivery tests for first delivery attempt */
2026
2027 case ECOND_FIRST_DELIVERY:
2028 if (yield != NULL) *yield = deliver_firsttime == testfor;
2029 return s;
2030
2031
2032 /* queue_running tests for any process started by a queue runner */
2033
2034 case ECOND_QUEUE_RUNNING:
2035 if (yield != NULL) *yield = (queue_run_pid != (pid_t)0) == testfor;
2036 return s;
2037
2038
2039 /* exists: tests for file existence
2040 isip: tests for any IP address
2041 isip4: tests for an IPv4 address
2042 isip6: tests for an IPv6 address
2043 pam: does PAM authentication
2044 radius: does RADIUS authentication
2045 ldapauth: does LDAP authentication
2046 pwcheck: does Cyrus SASL pwcheck authentication
2047 */
2048
2049 case ECOND_EXISTS:
2050 case ECOND_ISIP:
2051 case ECOND_ISIP4:
2052 case ECOND_ISIP6:
2053 case ECOND_PAM:
2054 case ECOND_RADIUS:
2055 case ECOND_LDAPAUTH:
2056 case ECOND_PWCHECK:
2057
2058 while (isspace(*s)) s++;
2059 if (*s != '{') goto COND_FAILED_CURLY_START; /* }-for-text-editors */
2060
2061 sub[0] = expand_string_internal(s+1, TRUE, &s, yield == NULL, TRUE);
2062 if (sub[0] == NULL) return NULL;
2063 /* {-for-text-editors */
2064 if (*s++ != '}') goto COND_FAILED_CURLY_END;
2065
2066 if (yield == NULL) return s; /* No need to run the test if skipping */
2067
2068 switch(cond_type)
2069 {
2070 case ECOND_EXISTS:
2071 if ((expand_forbid & RDO_EXISTS) != 0)
2072 {
2073 expand_string_message = US"File existence tests are not permitted";
2074 return NULL;
2075 }
2076 *yield = (Ustat(sub[0], &statbuf) == 0) == testfor;
2077 break;
2078
2079 case ECOND_ISIP:
2080 case ECOND_ISIP4:
2081 case ECOND_ISIP6:
2082 rc = string_is_ip_address(sub[0], NULL);
2083 *yield = ((cond_type == ECOND_ISIP)? (rc != 0) :
2084 (cond_type == ECOND_ISIP4)? (rc == 4) : (rc == 6)) == testfor;
2085 break;
2086
2087 /* Various authentication tests - all optionally compiled */
2088
2089 case ECOND_PAM:
2090 #ifdef SUPPORT_PAM
2091 rc = auth_call_pam(sub[0], &expand_string_message);
2092 goto END_AUTH;
2093 #else
2094 goto COND_FAILED_NOT_COMPILED;
2095 #endif /* SUPPORT_PAM */
2096
2097 case ECOND_RADIUS:
2098 #ifdef RADIUS_CONFIG_FILE
2099 rc = auth_call_radius(sub[0], &expand_string_message);
2100 goto END_AUTH;
2101 #else
2102 goto COND_FAILED_NOT_COMPILED;
2103 #endif /* RADIUS_CONFIG_FILE */
2104
2105 case ECOND_LDAPAUTH:
2106 #ifdef LOOKUP_LDAP
2107 {
2108 /* Just to keep the interface the same */
2109 BOOL do_cache;
2110 int old_pool = store_pool;
2111 store_pool = POOL_SEARCH;
2112 rc = eldapauth_find((void *)(-1), NULL, sub[0], Ustrlen(sub[0]), NULL,
2113 &expand_string_message, &do_cache);
2114 store_pool = old_pool;
2115 }
2116 goto END_AUTH;
2117 #else
2118 goto COND_FAILED_NOT_COMPILED;
2119 #endif /* LOOKUP_LDAP */
2120
2121 case ECOND_PWCHECK:
2122 #ifdef CYRUS_PWCHECK_SOCKET
2123 rc = auth_call_pwcheck(sub[0], &expand_string_message);
2124 goto END_AUTH;
2125 #else
2126 goto COND_FAILED_NOT_COMPILED;
2127 #endif /* CYRUS_PWCHECK_SOCKET */
2128
2129 #if defined(SUPPORT_PAM) || defined(RADIUS_CONFIG_FILE) || \
2130 defined(LOOKUP_LDAP) || defined(CYRUS_PWCHECK_SOCKET)
2131 END_AUTH:
2132 if (rc == ERROR || rc == DEFER) return NULL;
2133 *yield = (rc == OK) == testfor;
2134 #endif
2135 }
2136 return s;
2137
2138
2139 /* call ACL (in a conditional context). Accept true, deny false.
2140 Defer is a forced-fail. Anything set by message= goes to $value.
2141 Up to ten parameters are used; we use the braces round the name+args
2142 like the saslauthd condition does, to permit a variable number of args.
2143 See also the expansion-item version EITEM_ACL and the traditional
2144 acl modifier ACLC_ACL.
2145 */
2146
2147 case ECOND_ACL:
2148 /* ${if acl {{name}{arg1}{arg2}...} {yes}{no}} */
2149 {
2150 uschar *user_msg;
2151 BOOL cond = FALSE;
2152 int size = 0;
2153 int ptr = 0;
2154
2155 while (isspace(*s)) s++;
2156 if (*s++ != '{') goto COND_FAILED_CURLY_START; /*}*/
2157
2158 switch(read_subs(sub, sizeof(sub)/sizeof(*sub), 1,
2159 &s, yield == NULL, TRUE, US"acl"))
2160 {
2161 case 1: expand_string_message = US"too few arguments or bracketing "
2162 "error for acl";
2163 case 2:
2164 case 3: return NULL;
2165 }
2166
2167 if (yield != NULL) switch(eval_acl(sub, sizeof(sub)/sizeof(*sub), &user_msg))
2168 {
2169 case OK:
2170 cond = TRUE;
2171 case FAIL:
2172 lookup_value = NULL;
2173 if (user_msg)
2174 {
2175 lookup_value = string_cat(NULL, &size, &ptr, user_msg, Ustrlen(user_msg));
2176 lookup_value[ptr] = '\0';
2177 }
2178 *yield = cond == testfor;
2179 break;
2180
2181 case DEFER:
2182 expand_string_forcedfail = TRUE;
2183 default:
2184 expand_string_message = string_sprintf("error from acl \"%s\"", sub[0]);
2185 return NULL;
2186 }
2187 return s;
2188 }
2189
2190
2191 /* saslauthd: does Cyrus saslauthd authentication. Four parameters are used:
2192
2193 ${if saslauthd {{username}{password}{service}{realm}} {yes}[no}}
2194
2195 However, the last two are optional. That is why the whole set is enclosed
2196 in their own set of braces. */
2197
2198 case ECOND_SASLAUTHD:
2199 #ifndef CYRUS_SASLAUTHD_SOCKET
2200 goto COND_FAILED_NOT_COMPILED;
2201 #else
2202 while (isspace(*s)) s++;
2203 if (*s++ != '{') goto COND_FAILED_CURLY_START; /* }-for-text-editors */
2204 switch(read_subs(sub, 4, 2, &s, yield == NULL, TRUE, US"saslauthd"))
2205 {
2206 case 1: expand_string_message = US"too few arguments or bracketing "
2207 "error for saslauthd";
2208 case 2:
2209 case 3: return NULL;
2210 }
2211 if (sub[2] == NULL) sub[3] = NULL; /* realm if no service */
2212 if (yield != NULL)
2213 {
2214 int rc;
2215 rc = auth_call_saslauthd(sub[0], sub[1], sub[2], sub[3],
2216 &expand_string_message);
2217 if (rc == ERROR || rc == DEFER) return NULL;
2218 *yield = (rc == OK) == testfor;
2219 }
2220 return s;
2221 #endif /* CYRUS_SASLAUTHD_SOCKET */
2222
2223
2224 /* symbolic operators for numeric and string comparison, and a number of
2225 other operators, all requiring two arguments.
2226
2227 crypteq: encrypts plaintext and compares against an encrypted text,
2228 using crypt(), crypt16(), MD5 or SHA-1
2229 inlist/inlisti: checks if first argument is in the list of the second
2230 match: does a regular expression match and sets up the numerical
2231 variables if it succeeds
2232 match_address: matches in an address list
2233 match_domain: matches in a domain list
2234 match_ip: matches a host list that is restricted to IP addresses
2235 match_local_part: matches in a local part list
2236 */
2237
2238 case ECOND_MATCH_ADDRESS:
2239 case ECOND_MATCH_DOMAIN:
2240 case ECOND_MATCH_IP:
2241 case ECOND_MATCH_LOCAL_PART:
2242 #ifndef EXPAND_LISTMATCH_RHS
2243 sub2_honour_dollar = FALSE;
2244 #endif
2245 /* FALLTHROUGH */
2246
2247 case ECOND_CRYPTEQ:
2248 case ECOND_INLIST:
2249 case ECOND_INLISTI:
2250 case ECOND_MATCH:
2251
2252 case ECOND_NUM_L: /* Numerical comparisons */
2253 case ECOND_NUM_LE:
2254 case ECOND_NUM_E:
2255 case ECOND_NUM_EE:
2256 case ECOND_NUM_G:
2257 case ECOND_NUM_GE:
2258
2259 case ECOND_STR_LT: /* String comparisons */
2260 case ECOND_STR_LTI:
2261 case ECOND_STR_LE:
2262 case ECOND_STR_LEI:
2263 case ECOND_STR_EQ:
2264 case ECOND_STR_EQI:
2265 case ECOND_STR_GT:
2266 case ECOND_STR_GTI:
2267 case ECOND_STR_GE:
2268 case ECOND_STR_GEI:
2269
2270 for (i = 0; i < 2; i++)
2271 {
2272 /* Sometimes, we don't expand substrings; too many insecure configurations
2273 created using match_address{}{} and friends, where the second param
2274 includes information from untrustworthy sources. */
2275 BOOL honour_dollar = TRUE;
2276 if ((i > 0) && !sub2_honour_dollar)
2277 honour_dollar = FALSE;
2278
2279 while (isspace(*s)) s++;
2280 if (*s != '{')
2281 {
2282 if (i == 0) goto COND_FAILED_CURLY_START;
2283 expand_string_message = string_sprintf("missing 2nd string in {} "
2284 "after \"%s\"", name);
2285 return NULL;
2286 }
2287 sub[i] = expand_string_internal(s+1, TRUE, &s, yield == NULL,
2288 honour_dollar);
2289 if (sub[i] == NULL) return NULL;
2290 if (*s++ != '}') goto COND_FAILED_CURLY_END;
2291
2292 /* Convert to numerical if required; we know that the names of all the
2293 conditions that compare numbers do not start with a letter. This just saves
2294 checking for them individually. */
2295
2296 if (!isalpha(name[0]) && yield != NULL)
2297 {
2298 if (sub[i][0] == 0)
2299 {
2300 num[i] = 0;
2301 DEBUG(D_expand)
2302 debug_printf("empty string cast to zero for numerical comparison\n");
2303 }
2304 else
2305 {
2306 num[i] = expand_string_integer(sub[i], FALSE);
2307 if (expand_string_message != NULL) return NULL;
2308 }
2309 }
2310 }
2311
2312 /* Result not required */
2313
2314 if (yield == NULL) return s;
2315
2316 /* Do an appropriate comparison */
2317
2318 switch(cond_type)
2319 {
2320 case ECOND_NUM_E:
2321 case ECOND_NUM_EE:
2322 tempcond = (num[0] == num[1]);
2323 break;
2324
2325 case ECOND_NUM_G:
2326 tempcond = (num[0] > num[1]);
2327 break;
2328
2329 case ECOND_NUM_GE:
2330 tempcond = (num[0] >= num[1]);
2331 break;
2332
2333 case ECOND_NUM_L:
2334 tempcond = (num[0] < num[1]);
2335 break;
2336
2337 case ECOND_NUM_LE:
2338 tempcond = (num[0] <= num[1]);
2339 break;
2340
2341 case ECOND_STR_LT:
2342 tempcond = (Ustrcmp(sub[0], sub[1]) < 0);
2343 break;
2344
2345 case ECOND_STR_LTI:
2346 tempcond = (strcmpic(sub[0], sub[1]) < 0);
2347 break;
2348
2349 case ECOND_STR_LE:
2350 tempcond = (Ustrcmp(sub[0], sub[1]) <= 0);
2351 break;
2352
2353 case ECOND_STR_LEI:
2354 tempcond = (strcmpic(sub[0], sub[1]) <= 0);
2355 break;
2356
2357 case ECOND_STR_EQ:
2358 tempcond = (Ustrcmp(sub[0], sub[1]) == 0);
2359 break;
2360
2361 case ECOND_STR_EQI:
2362 tempcond = (strcmpic(sub[0], sub[1]) == 0);
2363 break;
2364
2365 case ECOND_STR_GT:
2366 tempcond = (Ustrcmp(sub[0], sub[1]) > 0);
2367 break;
2368
2369 case ECOND_STR_GTI:
2370 tempcond = (strcmpic(sub[0], sub[1]) > 0);
2371 break;
2372
2373 case ECOND_STR_GE:
2374 tempcond = (Ustrcmp(sub[0], sub[1]) >= 0);
2375 break;
2376
2377 case ECOND_STR_GEI:
2378 tempcond = (strcmpic(sub[0], sub[1]) >= 0);
2379 break;
2380
2381 case ECOND_MATCH: /* Regular expression match */
2382 re = pcre_compile(CS sub[1], PCRE_COPT, (const char **)&rerror, &roffset,
2383 NULL);
2384 if (re == NULL)
2385 {
2386 expand_string_message = string_sprintf("regular expression error in "
2387 "\"%s\": %s at offset %d", sub[1], rerror, roffset);
2388 return NULL;
2389 }
2390 tempcond = regex_match_and_setup(re, sub[0], 0, -1);
2391 break;
2392
2393 case ECOND_MATCH_ADDRESS: /* Match in an address list */
2394 rc = match_address_list(sub[0], TRUE, FALSE, &(sub[1]), NULL, -1, 0, NULL);
2395 goto MATCHED_SOMETHING;
2396
2397 case ECOND_MATCH_DOMAIN: /* Match in a domain list */
2398 rc = match_isinlist(sub[0], &(sub[1]), 0, &domainlist_anchor, NULL,
2399 MCL_DOMAIN + MCL_NOEXPAND, TRUE, NULL);
2400 goto MATCHED_SOMETHING;
2401
2402 case ECOND_MATCH_IP: /* Match IP address in a host list */
2403 if (sub[0][0] != 0 && string_is_ip_address(sub[0], NULL) == 0)
2404 {
2405 expand_string_message = string_sprintf("\"%s\" is not an IP address",
2406 sub[0]);
2407 return NULL;
2408 }
2409 else
2410 {
2411 unsigned int *nullcache = NULL;
2412 check_host_block cb;
2413
2414 cb.host_name = US"";
2415 cb.host_address = sub[0];
2416
2417 /* If the host address starts off ::ffff: it is an IPv6 address in
2418 IPv4-compatible mode. Find the IPv4 part for checking against IPv4
2419 addresses. */
2420
2421 cb.host_ipv4 = (Ustrncmp(cb.host_address, "::ffff:", 7) == 0)?
2422 cb.host_address + 7 : cb.host_address;
2423
2424 rc = match_check_list(
2425 &sub[1], /* the list */
2426 0, /* separator character */
2427 &hostlist_anchor, /* anchor pointer */
2428 &nullcache, /* cache pointer */
2429 check_host, /* function for testing */
2430 &cb, /* argument for function */
2431 MCL_HOST, /* type of check */
2432 sub[0], /* text for debugging */
2433 NULL); /* where to pass back data */
2434 }
2435 goto MATCHED_SOMETHING;
2436
2437 case ECOND_MATCH_LOCAL_PART:
2438 rc = match_isinlist(sub[0], &(sub[1]), 0, &localpartlist_anchor, NULL,
2439 MCL_LOCALPART + MCL_NOEXPAND, TRUE, NULL);
2440 /* Fall through */
2441 /* VVVVVVVVVVVV */
2442 MATCHED_SOMETHING:
2443 switch(rc)
2444 {
2445 case OK:
2446 tempcond = TRUE;
2447 break;
2448
2449 case FAIL:
2450 tempcond = FALSE;
2451 break;
2452
2453 case DEFER:
2454 expand_string_message = string_sprintf("unable to complete match "
2455 "against \"%s\": %s", sub[1], search_error_message);
2456 return NULL;
2457 }
2458
2459 break;
2460
2461 /* Various "encrypted" comparisons. If the second string starts with
2462 "{" then an encryption type is given. Default to crypt() or crypt16()
2463 (build-time choice). */
2464 /* }-for-text-editors */
2465
2466 case ECOND_CRYPTEQ:
2467 #ifndef SUPPORT_CRYPTEQ
2468 goto COND_FAILED_NOT_COMPILED;
2469 #else
2470 if (strncmpic(sub[1], US"{md5}", 5) == 0)
2471 {
2472 int sublen = Ustrlen(sub[1]+5);
2473 md5 base;
2474 uschar digest[16];
2475
2476 md5_start(&base);
2477 md5_end(&base, (uschar *)sub[0], Ustrlen(sub[0]), digest);
2478
2479 /* If the length that we are comparing against is 24, the MD5 digest
2480 is expressed as a base64 string. This is the way LDAP does it. However,
2481 some other software uses a straightforward hex representation. We assume
2482 this if the length is 32. Other lengths fail. */
2483
2484 if (sublen == 24)
2485 {
2486 uschar *coded = auth_b64encode((uschar *)digest, 16);
2487 DEBUG(D_auth) debug_printf("crypteq: using MD5+B64 hashing\n"
2488 " subject=%s\n crypted=%s\n", coded, sub[1]+5);
2489 tempcond = (Ustrcmp(coded, sub[1]+5) == 0);
2490 }
2491 else if (sublen == 32)
2492 {
2493 int i;
2494 uschar coded[36];
2495 for (i = 0; i < 16; i++) sprintf(CS (coded+2*i), "%02X", digest[i]);
2496 coded[32] = 0;
2497 DEBUG(D_auth) debug_printf("crypteq: using MD5+hex hashing\n"
2498 " subject=%s\n crypted=%s\n", coded, sub[1]+5);
2499 tempcond = (strcmpic(coded, sub[1]+5) == 0);
2500 }
2501 else
2502 {
2503 DEBUG(D_auth) debug_printf("crypteq: length for MD5 not 24 or 32: "
2504 "fail\n crypted=%s\n", sub[1]+5);
2505 tempcond = FALSE;
2506 }
2507 }
2508
2509 else if (strncmpic(sub[1], US"{sha1}", 6) == 0)
2510 {
2511 int sublen = Ustrlen(sub[1]+6);
2512 sha1 base;
2513 uschar digest[20];
2514
2515 sha1_start(&base);
2516 sha1_end(&base, (uschar *)sub[0], Ustrlen(sub[0]), digest);
2517
2518 /* If the length that we are comparing against is 28, assume the SHA1
2519 digest is expressed as a base64 string. If the length is 40, assume a
2520 straightforward hex representation. Other lengths fail. */
2521
2522 if (sublen == 28)
2523 {
2524 uschar *coded = auth_b64encode((uschar *)digest, 20);
2525 DEBUG(D_auth) debug_printf("crypteq: using SHA1+B64 hashing\n"
2526 " subject=%s\n crypted=%s\n", coded, sub[1]+6);
2527 tempcond = (Ustrcmp(coded, sub[1]+6) == 0);
2528 }
2529 else if (sublen == 40)
2530 {
2531 int i;
2532 uschar coded[44];
2533 for (i = 0; i < 20; i++) sprintf(CS (coded+2*i), "%02X", digest[i]);
2534 coded[40] = 0;
2535 DEBUG(D_auth) debug_printf("crypteq: using SHA1+hex hashing\n"
2536 " subject=%s\n crypted=%s\n", coded, sub[1]+6);
2537 tempcond = (strcmpic(coded, sub[1]+6) == 0);
2538 }
2539 else
2540 {
2541 DEBUG(D_auth) debug_printf("crypteq: length for SHA-1 not 28 or 40: "
2542 "fail\n crypted=%s\n", sub[1]+6);
2543 tempcond = FALSE;
2544 }
2545 }
2546
2547 else /* {crypt} or {crypt16} and non-{ at start */
2548 /* }-for-text-editors */
2549 {
2550 int which = 0;
2551 uschar *coded;
2552
2553 if (strncmpic(sub[1], US"{crypt}", 7) == 0)
2554 {
2555 sub[1] += 7;
2556 which = 1;
2557 }
2558 else if (strncmpic(sub[1], US"{crypt16}", 9) == 0)
2559 {
2560 sub[1] += 9;
2561 which = 2;
2562 }
2563 else if (sub[1][0] == '{') /* }-for-text-editors */
2564 {
2565 expand_string_message = string_sprintf("unknown encryption mechanism "
2566 "in \"%s\"", sub[1]);
2567 return NULL;
2568 }
2569
2570 switch(which)
2571 {
2572 case 0: coded = US DEFAULT_CRYPT(CS sub[0], CS sub[1]); break;
2573 case 1: coded = US crypt(CS sub[0], CS sub[1]); break;
2574 default: coded = US crypt16(CS sub[0], CS sub[1]); break;
2575 }
2576
2577 #define STR(s) # s
2578 #define XSTR(s) STR(s)
2579 DEBUG(D_auth) debug_printf("crypteq: using %s()\n"
2580 " subject=%s\n crypted=%s\n",
2581 (which == 0)? XSTR(DEFAULT_CRYPT) : (which == 1)? "crypt" : "crypt16",
2582 coded, sub[1]);
2583 #undef STR
2584 #undef XSTR
2585
2586 /* If the encrypted string contains fewer than two characters (for the
2587 salt), force failure. Otherwise we get false positives: with an empty
2588 string the yield of crypt() is an empty string! */
2589
2590 tempcond = (Ustrlen(sub[1]) < 2)? FALSE :
2591 (Ustrcmp(coded, sub[1]) == 0);
2592 }
2593 break;
2594 #endif /* SUPPORT_CRYPTEQ */
2595
2596 case ECOND_INLIST:
2597 case ECOND_INLISTI:
2598 {
2599 int sep = 0;
2600 uschar *save_iterate_item = iterate_item;
2601 int (*compare)(const uschar *, const uschar *);
2602
2603 tempcond = FALSE;
2604 if (cond_type == ECOND_INLISTI)
2605 compare = strcmpic;
2606 else
2607 compare = (int (*)(const uschar *, const uschar *)) strcmp;
2608
2609 while ((iterate_item = string_nextinlist(&sub[1], &sep, NULL, 0)) != NULL)
2610 if (compare(sub[0], iterate_item) == 0)
2611 {
2612 tempcond = TRUE;
2613 break;
2614 }
2615 iterate_item = save_iterate_item;
2616 }
2617
2618 } /* Switch for comparison conditions */
2619
2620 *yield = tempcond == testfor;
2621 return s; /* End of comparison conditions */
2622
2623
2624 /* and/or: computes logical and/or of several conditions */
2625
2626 case ECOND_AND:
2627 case ECOND_OR:
2628 subcondptr = (yield == NULL)? NULL : &tempcond;
2629 combined_cond = (cond_type == ECOND_AND);
2630
2631 while (isspace(*s)) s++;
2632 if (*s++ != '{') goto COND_FAILED_CURLY_START; /* }-for-text-editors */
2633
2634 for (;;)
2635 {
2636 while (isspace(*s)) s++;
2637 /* {-for-text-editors */
2638 if (*s == '}') break;
2639 if (*s != '{') /* }-for-text-editors */
2640 {
2641 expand_string_message = string_sprintf("each subcondition "
2642 "inside an \"%s{...}\" condition must be in its own {}", name);
2643 return NULL;
2644 }
2645
2646 s = eval_condition(s+1, subcondptr);
2647 if (s == NULL)
2648 {
2649 expand_string_message = string_sprintf("%s inside \"%s{...}\" condition",
2650 expand_string_message, name);
2651 return NULL;
2652 }
2653 while (isspace(*s)) s++;
2654
2655 /* {-for-text-editors */
2656 if (*s++ != '}')
2657 {
2658 /* {-for-text-editors */
2659 expand_string_message = string_sprintf("missing } at end of condition "
2660 "inside \"%s\" group", name);
2661 return NULL;
2662 }
2663
2664 if (yield != NULL)
2665 {
2666 if (cond_type == ECOND_AND)
2667 {
2668 combined_cond &= tempcond;
2669 if (!combined_cond) subcondptr = NULL; /* once false, don't */
2670 } /* evaluate any more */
2671 else
2672 {
2673 combined_cond |= tempcond;
2674 if (combined_cond) subcondptr = NULL; /* once true, don't */
2675 } /* evaluate any more */
2676 }
2677 }
2678
2679 if (yield != NULL) *yield = (combined_cond == testfor);
2680 return ++s;
2681
2682
2683 /* forall/forany: iterates a condition with different values */
2684
2685 case ECOND_FORALL:
2686 case ECOND_FORANY:
2687 {
2688 int sep = 0;
2689 uschar *save_iterate_item = iterate_item;
2690
2691 while (isspace(*s)) s++;
2692 if (*s++ != '{') goto COND_FAILED_CURLY_START; /* }-for-text-editors */
2693 sub[0] = expand_string_internal(s, TRUE, &s, (yield == NULL), TRUE);
2694 if (sub[0] == NULL) return NULL;
2695 /* {-for-text-editors */
2696 if (*s++ != '}') goto COND_FAILED_CURLY_END;
2697
2698 while (isspace(*s)) s++;
2699 if (*s++ != '{') goto COND_FAILED_CURLY_START; /* }-for-text-editors */
2700
2701 sub[1] = s;
2702
2703 /* Call eval_condition once, with result discarded (as if scanning a
2704 "false" part). This allows us to find the end of the condition, because if
2705 the list it empty, we won't actually evaluate the condition for real. */
2706
2707 s = eval_condition(sub[1], NULL);
2708 if (s == NULL)
2709 {
2710 expand_string_message = string_sprintf("%s inside \"%s\" condition",
2711 expand_string_message, name);
2712 return NULL;
2713 }
2714 while (isspace(*s)) s++;
2715
2716 /* {-for-text-editors */
2717 if (*s++ != '}')
2718 {
2719 /* {-for-text-editors */
2720 expand_string_message = string_sprintf("missing } at end of condition "
2721 "inside \"%s\"", name);
2722 return NULL;
2723 }
2724
2725 if (yield != NULL) *yield = !testfor;
2726 while ((iterate_item = string_nextinlist(&sub[0], &sep, NULL, 0)) != NULL)
2727 {
2728 DEBUG(D_expand) debug_printf("%s: $item = \"%s\"\n", name, iterate_item);
2729 if (eval_condition(sub[1], &tempcond) == NULL)
2730 {
2731 expand_string_message = string_sprintf("%s inside \"%s\" condition",
2732 expand_string_message, name);
2733 iterate_item = save_iterate_item;
2734 return NULL;
2735 }
2736 DEBUG(D_expand) debug_printf("%s: condition evaluated to %s\n", name,
2737 tempcond? "true":"false");
2738
2739 if (yield != NULL) *yield = (tempcond == testfor);
2740 if (tempcond == (cond_type == ECOND_FORANY)) break;
2741 }
2742
2743 iterate_item = save_iterate_item;
2744 return s;
2745 }
2746
2747
2748 /* The bool{} expansion condition maps a string to boolean.
2749 The values supported should match those supported by the ACL condition
2750 (acl.c, ACLC_CONDITION) so that we keep to a minimum the different ideas
2751 of true/false. Note that Router "condition" rules have a different
2752 interpretation, where general data can be used and only a few values
2753 map to FALSE.
2754 Note that readconf.c boolean matching, for boolean configuration options,
2755 only matches true/yes/false/no.
2756 The bool_lax{} condition matches the Router logic, which is much more
2757 liberal. */
2758 case ECOND_BOOL:
2759 case ECOND_BOOL_LAX:
2760 {
2761 uschar *sub_arg[1];
2762 uschar *t, *t2;
2763 uschar *ourname;
2764 size_t len;
2765 BOOL boolvalue = FALSE;
2766 while (isspace(*s)) s++;
2767 if (*s != '{') goto COND_FAILED_CURLY_START; /* }-for-text-editors */
2768 ourname = cond_type == ECOND_BOOL_LAX ? US"bool_lax" : US"bool";
2769 switch(read_subs(sub_arg, 1, 1, &s, yield == NULL, FALSE, ourname))
2770 {
2771 case 1: expand_string_message = string_sprintf(
2772 "too few arguments or bracketing error for %s",
2773 ourname);
2774 /*FALLTHROUGH*/
2775 case 2:
2776 case 3: return NULL;
2777 }
2778 t = sub_arg[0];
2779 while (isspace(*t)) t++;
2780 len = Ustrlen(t);
2781 if (len)
2782 {
2783 /* trailing whitespace: seems like a good idea to ignore it too */
2784 t2 = t + len - 1;
2785 while (isspace(*t2)) t2--;
2786 if (t2 != (t + len))
2787 {
2788 *++t2 = '\0';
2789 len = t2 - t;
2790 }
2791 }
2792 DEBUG(D_expand)
2793 debug_printf("considering %s: %s\n", ourname, len ? t : US"<empty>");
2794 /* logic for the lax case from expand_check_condition(), which also does
2795 expands, and the logic is both short and stable enough that there should
2796 be no maintenance burden from replicating it. */
2797 if (len == 0)
2798 boolvalue = FALSE;
2799 else if (Ustrspn(t, "0123456789") == len)
2800 {
2801 boolvalue = (Uatoi(t) == 0) ? FALSE : TRUE;
2802 /* expand_check_condition only does a literal string "0" check */
2803 if ((cond_type == ECOND_BOOL_LAX) && (len > 1))
2804 boolvalue = TRUE;
2805 }
2806 else if (strcmpic(t, US"true") == 0 || strcmpic(t, US"yes") == 0)
2807 boolvalue = TRUE;
2808 else if (strcmpic(t, US"false") == 0 || strcmpic(t, US"no") == 0)
2809 boolvalue = FALSE;
2810 else if (cond_type == ECOND_BOOL_LAX)
2811 boolvalue = TRUE;
2812 else
2813 {
2814 expand_string_message = string_sprintf("unrecognised boolean "
2815 "value \"%s\"", t);
2816 return NULL;
2817 }
2818 if (yield != NULL) *yield = (boolvalue == testfor);
2819 return s;
2820 }
2821
2822 /* Unknown condition */
2823
2824 default:
2825 expand_string_message = string_sprintf("unknown condition \"%s\"", name);
2826 return NULL;
2827 } /* End switch on condition type */
2828
2829 /* Missing braces at start and end of data */
2830
2831 COND_FAILED_CURLY_START:
2832 expand_string_message = string_sprintf("missing { after \"%s\"", name);
2833 return NULL;
2834
2835 COND_FAILED_CURLY_END:
2836 expand_string_message = string_sprintf("missing } at end of \"%s\" condition",
2837 name);
2838 return NULL;
2839
2840 /* A condition requires code that is not compiled */
2841
2842 #if !defined(SUPPORT_PAM) || !defined(RADIUS_CONFIG_FILE) || \
2843 !defined(LOOKUP_LDAP) || !defined(CYRUS_PWCHECK_SOCKET) || \
2844 !defined(SUPPORT_CRYPTEQ) || !defined(CYRUS_SASLAUTHD_SOCKET)
2845 COND_FAILED_NOT_COMPILED:
2846 expand_string_message = string_sprintf("support for \"%s\" not compiled",
2847 name);
2848 return NULL;
2849 #endif
2850 }
2851
2852
2853
2854
2855 /*************************************************
2856 * Save numerical variables *
2857 *************************************************/
2858
2859 /* This function is called from items such as "if" that want to preserve and
2860 restore the numbered variables.
2861
2862 Arguments:
2863 save_expand_string points to an array of pointers to set
2864 save_expand_nlength points to an array of ints for the lengths
2865
2866 Returns: the value of expand max to save
2867 */
2868
2869 static int
2870 save_expand_strings(uschar **save_expand_nstring, int *save_expand_nlength)
2871 {
2872 int i;
2873 for (i = 0; i <= expand_nmax; i++)
2874 {
2875 save_expand_nstring[i] = expand_nstring[i];
2876 save_expand_nlength[i] = expand_nlength[i];
2877 }
2878 return expand_nmax;
2879 }
2880
2881
2882
2883 /*************************************************
2884 * Restore numerical variables *
2885 *************************************************/
2886
2887 /* This function restored saved values of numerical strings.
2888
2889 Arguments:
2890 save_expand_nmax the number of strings to restore
2891 save_expand_string points to an array of pointers
2892 save_expand_nlength points to an array of ints
2893
2894 Returns: nothing
2895 */
2896
2897 static void
2898 restore_expand_strings(int save_expand_nmax, uschar **save_expand_nstring,
2899 int *save_expand_nlength)
2900 {
2901 int i;
2902 expand_nmax = save_expand_nmax;
2903 for (i = 0; i <= expand_nmax; i++)
2904 {
2905 expand_nstring[i] = save_expand_nstring[i];
2906 expand_nlength[i] = save_expand_nlength[i];
2907 }
2908 }
2909
2910
2911
2912
2913
2914 /*************************************************
2915 * Handle yes/no substrings *
2916 *************************************************/
2917
2918 /* This function is used by ${if}, ${lookup} and ${extract} to handle the
2919 alternative substrings that depend on whether or not the condition was true,
2920 or the lookup or extraction succeeded. The substrings always have to be
2921 expanded, to check their syntax, but "skipping" is set when the result is not
2922 needed - this avoids unnecessary nested lookups.
2923
2924 Arguments:
2925 skipping TRUE if we were skipping when this item was reached
2926 yes TRUE if the first string is to be used, else use the second
2927 save_lookup a value to put back into lookup_value before the 2nd expansion
2928 sptr points to the input string pointer
2929 yieldptr points to the output string pointer
2930 sizeptr points to the output string size
2931 ptrptr points to the output string pointer
2932 type "lookup" or "if" or "extract" or "run", for error message
2933
2934 Returns: 0 OK; lookup_value has been reset to save_lookup
2935 1 expansion failed
2936 2 expansion failed because of bracketing error
2937 */
2938
2939 static int
2940 process_yesno(BOOL skipping, BOOL yes, uschar *save_lookup, uschar **sptr,
2941 uschar **yieldptr, int *sizeptr, int *ptrptr, uschar *type)
2942 {
2943 int rc = 0;
2944 uschar *s = *sptr; /* Local value */
2945 uschar *sub1, *sub2;
2946
2947 /* If there are no following strings, we substitute the contents of $value for
2948 lookups and for extractions in the success case. For the ${if item, the string
2949 "true" is substituted. In the fail case, nothing is substituted for all three
2950 items. */
2951
2952 while (isspace(*s)) s++;
2953 if (*s == '}')
2954 {
2955 if (type[0] == 'i')
2956 {
2957 if (yes) *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, US"true", 4);
2958 }
2959 else
2960 {
2961 if (yes && lookup_value != NULL)
2962 *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, lookup_value,
2963 Ustrlen(lookup_value));
2964 lookup_value = save_lookup;
2965 }
2966 s++;
2967 goto RETURN;
2968 }
2969
2970 /* The first following string must be braced. */
2971
2972 if (*s++ != '{') goto FAILED_CURLY;
2973
2974 /* Expand the first substring. Forced failures are noticed only if we actually
2975 want this string. Set skipping in the call in the fail case (this will always
2976 be the case if we were already skipping). */
2977
2978 sub1 = expand_string_internal(s, TRUE, &s, !yes, TRUE);
2979 if (sub1 == NULL && (yes || !expand_string_forcedfail)) goto FAILED;
2980 expand_string_forcedfail = FALSE;
2981 if (*s++ != '}') goto FAILED_CURLY;
2982
2983 /* If we want the first string, add it to the output */
2984
2985 if (yes)
2986 *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, sub1, Ustrlen(sub1));
2987
2988 /* If this is called from a lookup or an extract, we want to restore $value to
2989 what it was at the start of the item, so that it has this value during the
2990 second string expansion. For the call from "if" or "run" to this function,
2991 save_lookup is set to lookup_value, so that this statement does nothing. */
2992
2993 lookup_value = save_lookup;
2994
2995 /* There now follows either another substring, or "fail", or nothing. This
2996 time, forced failures are noticed only if we want the second string. We must
2997 set skipping in the nested call if we don't want this string, or if we were
2998 already skipping. */
2999
3000 while (isspace(*s)) s++;
3001 if (*s == '{')
3002 {
3003 sub2 = expand_string_internal(s+1, TRUE, &s, yes || skipping, TRUE);
3004 if (sub2 == NULL && (!yes || !expand_string_forcedfail)) goto FAILED;
3005 expand_string_forcedfail = FALSE;
3006 if (*s++ != '}') goto FAILED_CURLY;
3007
3008 /* If we want the second string, add it to the output */
3009
3010 if (!yes)
3011 *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, sub2, Ustrlen(sub2));
3012 }
3013
3014 /* If there is no second string, but the word "fail" is present when the use of
3015 the second string is wanted, set a flag indicating it was a forced failure
3016 rather than a syntactic error. Swallow the terminating } in case this is nested
3017 inside another lookup or if or extract. */
3018
3019 else if (*s != '}')
3020 {
3021 uschar name[256];
3022 s = read_name(name, sizeof(name), s, US"_");
3023 if (Ustrcmp(name, "fail") == 0)
3024 {
3025 if (!yes && !skipping)
3026 {
3027 while (isspace(*s)) s++;
3028 if (*s++ != '}') goto FAILED_CURLY;
3029 expand_string_message =
3030 string_sprintf("\"%s\" failed and \"fail\" requested", type);
3031 expand_string_forcedfail = TRUE;
3032 goto FAILED;
3033 }
3034 }
3035 else
3036 {
3037 expand_string_message =
3038 string_sprintf("syntax error in \"%s\" item - \"fail\" expected", type);
3039 goto FAILED;
3040 }
3041 }
3042
3043 /* All we have to do now is to check on the final closing brace. */
3044
3045 while (isspace(*s)) s++;
3046 if (*s++ == '}') goto RETURN;
3047
3048 /* Get here if there is a bracketing failure */
3049
3050 FAILED_CURLY:
3051 rc++;
3052
3053 /* Get here for other failures */
3054
3055 FAILED:
3056 rc++;
3057
3058 /* Update the input pointer value before returning */
3059
3060 RETURN:
3061 *sptr = s;
3062 return rc;
3063 }
3064
3065
3066
3067
3068 /*************************************************
3069 * Handle MD5 or SHA-1 computation for HMAC *
3070 *************************************************/
3071
3072 /* These are some wrapping functions that enable the HMAC code to be a bit
3073 cleaner. A good compiler will spot the tail recursion.
3074
3075 Arguments:
3076 type HMAC_MD5 or HMAC_SHA1
3077 remaining are as for the cryptographic hash functions
3078
3079 Returns: nothing
3080 */
3081
3082 static void
3083 chash_start(int type, void *base)
3084 {
3085 if (type == HMAC_MD5)
3086 md5_start((md5 *)base);
3087 else
3088 sha1_start((sha1 *)base);
3089 }
3090
3091 static void
3092 chash_mid(int type, void *base, uschar *string)
3093 {
3094 if (type == HMAC_MD5)
3095 md5_mid((md5 *)base, string);
3096 else
3097 sha1_mid((sha1 *)base, string);
3098 }
3099
3100 static void
3101 chash_end(int type, void *base, uschar *string, int length, uschar *digest)
3102 {
3103 if (type == HMAC_MD5)
3104 md5_end((md5 *)base, string, length, digest);
3105 else
3106 sha1_end((sha1 *)base, string, length, digest);
3107 }
3108
3109
3110
3111
3112
3113 /********************************************************
3114 * prvs: Get last three digits of days since Jan 1, 1970 *
3115 ********************************************************/
3116
3117 /* This is needed to implement the "prvs" BATV reverse
3118 path signing scheme
3119
3120 Argument: integer "days" offset to add or substract to
3121 or from the current number of days.
3122
3123 Returns: pointer to string containing the last three
3124 digits of the number of days since Jan 1, 1970,
3125 modified by the offset argument, NULL if there
3126 was an error in the conversion.
3127
3128 */
3129
3130 static uschar *
3131 prvs_daystamp(int day_offset)
3132 {
3133 uschar *days = store_get(32); /* Need at least 24 for cases */
3134 (void)string_format(days, 32, TIME_T_FMT, /* where TIME_T_FMT is %lld */
3135 (time(NULL) + day_offset*86400)/86400);
3136 return (Ustrlen(days) >= 3) ? &days[Ustrlen(days)-3] : US"100";
3137 }
3138
3139
3140
3141 /********************************************************
3142 * prvs: perform HMAC-SHA1 computation of prvs bits *
3143 ********************************************************/
3144
3145 /* This is needed to implement the "prvs" BATV reverse
3146 path signing scheme
3147
3148 Arguments:
3149 address RFC2821 Address to use
3150 key The key to use (must be less than 64 characters
3151 in size)
3152 key_num Single-digit key number to use. Defaults to
3153 '0' when NULL.
3154
3155 Returns: pointer to string containing the first three
3156 bytes of the final hash in hex format, NULL if
3157 there was an error in the process.
3158 */
3159
3160 static uschar *
3161 prvs_hmac_sha1(uschar *address, uschar *key, uschar *key_num, uschar *daystamp)
3162 {
3163 uschar *hash_source, *p;
3164 int size = 0,offset = 0,i;
3165 sha1 sha1_base;
3166 void *use_base = &sha1_base;
3167 uschar innerhash[20];
3168 uschar finalhash[20];
3169 uschar innerkey[64];
3170 uschar outerkey[64];
3171 uschar *finalhash_hex = store_get(40);
3172
3173 if (key_num == NULL)
3174 key_num = US"0";
3175
3176 if (Ustrlen(key) > 64)
3177 return NULL;
3178
3179 hash_source = string_cat(NULL,&size,&offset,key_num,1);
3180 string_cat(hash_source,&size,&offset,daystamp,3);
3181 string_cat(hash_source,&size,&offset,address,Ustrlen(address));
3182 hash_source[offset] = '\0';
3183
3184 DEBUG(D_expand) debug_printf("prvs: hash source is '%s'\n", hash_source);
3185
3186 memset(innerkey, 0x36, 64);
3187 memset(outerkey, 0x5c, 64);
3188
3189 for (i = 0; i < Ustrlen(key); i++)
3190 {
3191 innerkey[i] ^= key[i];
3192 outerkey[i] ^= key[i];
3193 }
3194
3195 chash_start(HMAC_SHA1, use_base);
3196 chash_mid(HMAC_SHA1, use_base, innerkey);
3197 chash_end(HMAC_SHA1, use_base, hash_source, offset, innerhash);
3198
3199 chash_start(HMAC_SHA1, use_base);
3200 chash_mid(HMAC_SHA1, use_base, outerkey);
3201 chash_end(HMAC_SHA1, use_base, innerhash, 20, finalhash);
3202
3203 p = finalhash_hex;
3204 for (i = 0; i < 3; i++)
3205 {
3206 *p++ = hex_digits[(finalhash[i] & 0xf0) >> 4];
3207 *p++ = hex_digits[finalhash[i] & 0x0f];
3208 }
3209 *p = '\0';
3210
3211 return finalhash_hex;
3212 }
3213
3214
3215
3216
3217 /*************************************************
3218 * Join a file onto the output string *
3219 *************************************************/
3220
3221 /* This is used for readfile and after a run expansion. It joins the contents
3222 of a file onto the output string, globally replacing newlines with a given
3223 string (optionally). The file is closed at the end.
3224
3225 Arguments:
3226 f the FILE
3227 yield pointer to the expandable string
3228 sizep pointer to the current size
3229 ptrp pointer to the current position
3230 eol newline replacement string, or NULL
3231
3232 Returns: new value of string pointer
3233 */
3234
3235 static uschar *
3236 cat_file(FILE *f, uschar *yield, int *sizep, int *ptrp, uschar *eol)
3237 {
3238 int eollen;
3239 uschar buffer[1024];
3240
3241 eollen = (eol == NULL)? 0 : Ustrlen(eol);
3242
3243 while (Ufgets(buffer, sizeof(buffer), f) != NULL)
3244 {
3245 int len = Ustrlen(buffer);
3246 if (eol != NULL && buffer[len-1] == '\n') len--;
3247 yield = string_cat(yield, sizep, ptrp, buffer, len);
3248 if (buffer[len] != 0)
3249 yield = string_cat(yield, sizep, ptrp, eol, eollen);
3250 }
3251
3252 if (yield != NULL) yield[*ptrp] = 0;
3253
3254 return yield;
3255 }
3256
3257
3258
3259
3260 /*************************************************
3261 * Evaluate numeric expression *
3262 *************************************************/
3263
3264 /* This is a set of mutually recursive functions that evaluate an arithmetic
3265 expression involving + - * / % & | ^ ~ << >> and parentheses. The only one of
3266 these functions that is called from elsewhere is eval_expr, whose interface is:
3267
3268 Arguments:
3269 sptr pointer to the pointer to the string - gets updated
3270 decimal TRUE if numbers are to be assumed decimal
3271 error pointer to where to put an error message - must be NULL on input
3272 endket TRUE if ')' must terminate - FALSE for external call
3273
3274 Returns: on success: the value of the expression, with *error still NULL
3275 on failure: an undefined value, with *error = a message
3276 */
3277
3278 static int_eximarith_t eval_op_or(uschar **, BOOL, uschar **);
3279
3280
3281 static int_eximarith_t
3282 eval_expr(uschar **sptr, BOOL decimal, uschar **error, BOOL endket)
3283 {
3284 uschar *s = *sptr;
3285 int_eximarith_t x = eval_op_or(&s, decimal, error);
3286 if (*error == NULL)
3287 {
3288 if (endket)
3289 {
3290 if (*s != ')')
3291 *error = US"expecting closing parenthesis";
3292 else
3293 while (isspace(*(++s)));
3294 }
3295 else if (*s != 0) *error = US"expecting operator";
3296 }
3297 *sptr = s;
3298 return x;
3299 }
3300
3301
3302 static int_eximarith_t
3303 eval_number(uschar **sptr, BOOL decimal, uschar **error)
3304 {
3305 register int c;
3306 int_eximarith_t n;
3307 uschar *s = *sptr;
3308 while (isspace(*s)) s++;
3309 c = *s;
3310 if (isdigit(c))
3311 {
3312 int count;
3313 (void)sscanf(CS s, (decimal? SC_EXIM_DEC "%n" : SC_EXIM_ARITH "%n"), &n, &count);
3314 s += count;
3315 switch (tolower(*s))
3316 {
3317 default: break;
3318 case 'k': n *= 1024; s++; break;
3319 case 'm': n *= 1024*1024; s++; break;
3320 case 'g': n *= 1024*1024*1024; s++; break;
3321 }
3322 while (isspace (*s)) s++;
3323 }
3324 else if (c == '(')
3325 {
3326 s++;
3327 n = eval_expr(&s, decimal, error, 1);
3328 }
3329 else
3330 {
3331 *error = US"expecting number or opening parenthesis";
3332 n = 0;
3333 }
3334 *sptr = s;
3335 return n;
3336 }
3337
3338
3339 static int_eximarith_t
3340 eval_op_unary(uschar **sptr, BOOL decimal, uschar **error)
3341 {
3342 uschar *s = *sptr;
3343 int_eximarith_t x;
3344 while (isspace(*s)) s++;
3345 if (*s == '+' || *s == '-' || *s == '~')
3346 {
3347 int op = *s++;
3348 x = eval_op_unary(&s, decimal, error);
3349 if (op == '-') x = -x;
3350 else if (op == '~') x = ~x;
3351 }
3352 else
3353 {
3354 x = eval_number(&s, decimal, error);
3355 }
3356 *sptr = s;
3357 return x;
3358 }
3359
3360
3361 static int_eximarith_t
3362 eval_op_mult(uschar **sptr, BOOL decimal, uschar **error)
3363 {
3364 uschar *s = *sptr;
3365 int_eximarith_t x = eval_op_unary(&s, decimal, error);
3366 if (*error == NULL)
3367 {
3368 while (*s == '*' || *s == '/' || *s == '%')
3369 {
3370 int op = *s++;
3371 int_eximarith_t y = eval_op_unary(&s, decimal, error);
3372 if (*error != NULL) break;
3373 /* SIGFPE both on div/mod by zero and on INT_MIN / -1, which would give
3374 * a value of INT_MAX+1. Note that INT_MIN * -1 gives INT_MIN for me, which
3375 * is a bug somewhere in [gcc 4.2.1, FreeBSD, amd64]. In fact, -N*-M where
3376 * -N*M is INT_MIN will yielf INT_MIN.
3377 * Since we don't support floating point, this is somewhat simpler.
3378 * Ideally, we'd return an error, but since we overflow for all other
3379 * arithmetic, consistency suggests otherwise, but what's the correct value
3380 * to use? There is none.
3381 * The C standard guarantees overflow for unsigned arithmetic but signed
3382 * overflow invokes undefined behaviour; in practice, this is overflow
3383 * except for converting INT_MIN to INT_MAX+1. We also can't guarantee
3384 * that long/longlong larger than int are available, or we could just work
3385 * with larger types. We should consider whether to guarantee 32bit eval
3386 * and 64-bit working variables, with errors returned. For now ...
3387 * So, the only SIGFPEs occur with a non-shrinking div/mod, thus -1; we
3388 * can just let the other invalid results occur otherwise, as they have
3389 * until now. For this one case, we can coerce.
3390 */
3391 if (y == -1 && x == LLONG_MIN && op != '*')
3392 {
3393 DEBUG(D_expand)
3394 debug_printf("Integer exception dodging: " PR_EXIM_ARITH "%c-1 coerced to " PR_EXIM_ARITH "\n",
3395 LLONG_MIN, op, LLONG_MAX);
3396 x = LLONG_MAX;
3397 continue;
3398 }
3399 if (op == '*')
3400 x *= y;
3401 else
3402 {
3403 if (y == 0)
3404 {
3405 *error = (op == '/') ? US"divide by zero" : US"modulo by zero";
3406 x = 0;
3407 break;
3408 }
3409 if (op == '/')
3410 x /= y;
3411 else
3412 x %= y;
3413 }
3414 }
3415 }
3416 *sptr = s;
3417 return x;
3418 }
3419
3420
3421 static int_eximarith_t
3422 eval_op_sum(uschar **sptr, BOOL decimal, uschar **error)
3423 {
3424 uschar *s = *sptr;
3425 int_eximarith_t x = eval_op_mult(&s, decimal, error);
3426 if (*error == NULL)
3427 {
3428 while (*s == '+' || *s == '-')
3429 {
3430 int op = *s++;
3431 int_eximarith_t y = eval_op_mult(&s, decimal, error);
3432 if (*error != NULL) break;
3433 if (op == '+') x += y; else x -= y;
3434 }
3435 }
3436 *sptr = s;
3437 return x;
3438 }
3439
3440
3441 static int_eximarith_t
3442 eval_op_shift(uschar **sptr, BOOL decimal, uschar **error)
3443 {
3444 uschar *s = *sptr;
3445 int_eximarith_t x = eval_op_sum(&s, decimal, error);
3446 if (*error == NULL)
3447 {
3448 while ((*s == '<' || *s == '>') && s[1] == s[0])
3449 {
3450 int_eximarith_t y;
3451 int op = *s++;
3452 s++;
3453 y = eval_op_sum(&s, decimal, error);
3454 if (*error != NULL) break;
3455 if (op == '<') x <<= y; else x >>= y;
3456 }
3457 }
3458 *sptr = s;
3459 return x;
3460 }
3461
3462
3463 static int_eximarith_t
3464 eval_op_and(uschar **sptr, BOOL decimal, uschar **error)
3465 {
3466 uschar *s = *sptr;
3467 int_eximarith_t x = eval_op_shift(&s, decimal, error);
3468 if (*error == NULL)
3469 {
3470 while (*s == '&')
3471 {
3472 int_eximarith_t y;
3473 s++;
3474 y = eval_op_shift(&s, decimal, error);
3475 if (*error != NULL) break;
3476 x &= y;
3477 }
3478 }
3479 *sptr = s;
3480 return x;
3481 }
3482
3483
3484 static int_eximarith_t
3485 eval_op_xor(uschar **sptr, BOOL decimal, uschar **error)
3486 {
3487 uschar *s = *sptr;
3488 int_eximarith_t x = eval_op_and(&s, decimal, error);
3489 if (*error == NULL)
3490 {
3491 while (*s == '^')
3492 {
3493 int_eximarith_t y;
3494 s++;
3495 y = eval_op_and(&s, decimal, error);
3496 if (*error != NULL) break;
3497 x ^= y;
3498 }
3499 }
3500 *sptr = s;
3501 return x;
3502 }
3503
3504
3505 static int_eximarith_t
3506 eval_op_or(uschar **sptr, BOOL decimal, uschar **error)
3507 {
3508 uschar *s = *sptr;
3509 int_eximarith_t x = eval_op_xor(&s, decimal, error);
3510 if (*error == NULL)
3511 {
3512 while (*s == '|')
3513 {
3514 int_eximarith_t y;
3515 s++;
3516 y = eval_op_xor(&s, decimal, error);
3517 if (*error != NULL) break;
3518 x |= y;
3519 }
3520 }
3521 *sptr = s;
3522 return x;
3523 }
3524
3525
3526
3527 /*************************************************
3528 * Expand string *
3529 *************************************************/
3530
3531 /* Returns either an unchanged string, or the expanded string in stacking pool
3532 store. Interpreted sequences are:
3533
3534 \... normal escaping rules
3535 $name substitutes the variable
3536 ${name} ditto
3537 ${op:string} operates on the expanded string value
3538 ${item{arg1}{arg2}...} expands the args and then does the business
3539 some literal args are not enclosed in {}
3540
3541 There are now far too many operators and item types to make it worth listing
3542 them here in detail any more.
3543
3544 We use an internal routine recursively to handle embedded substrings. The
3545 external function follows. The yield is NULL if the expansion failed, and there
3546 are two cases: if something collapsed syntactically, or if "fail" was given
3547 as the action on a lookup failure. These can be distinguised by looking at the
3548 variable expand_string_forcedfail, which is TRUE in the latter case.
3549
3550 The skipping flag is set true when expanding a substring that isn't actually
3551 going to be used (after "if" or "lookup") and it prevents lookups from
3552 happening lower down.
3553
3554 Store usage: At start, a store block of the length of the input plus 64
3555 is obtained. This is expanded as necessary by string_cat(), which might have to
3556 get a new block, or might be able to expand the original. At the end of the
3557 function we can release any store above that portion of the yield block that
3558 was actually used. In many cases this will be optimal.
3559
3560 However: if the first item in the expansion is a variable name or header name,
3561 we reset the store before processing it; if the result is in fresh store, we
3562 use that without copying. This is helpful for expanding strings like
3563 $message_headers which can get very long.
3564
3565 There's a problem if a ${dlfunc item has side-effects that cause allocation,
3566 since resetting the store at the end of the expansion will free store that was
3567 allocated by the plugin code as well as the slop after the expanded string. So
3568 we skip any resets if ${dlfunc has been used. The same applies for ${acl. This
3569 is an unfortunate consequence of string expansion becoming too powerful.
3570
3571 Arguments:
3572 string the string to be expanded
3573 ket_ends true if expansion is to stop at }
3574 left if not NULL, a pointer to the first character after the
3575 expansion is placed here (typically used with ket_ends)
3576 skipping TRUE for recursive calls when the value isn't actually going
3577 to be used (to allow for optimisation)
3578 honour_dollar TRUE if $ is to be expanded,
3579 FALSE if it's just another character
3580
3581 Returns: NULL if expansion fails:
3582 expand_string_forcedfail is set TRUE if failure was forced
3583 expand_string_message contains a textual error message
3584 a pointer to the expanded string on success
3585 */
3586
3587 static uschar *
3588 expand_string_internal(uschar *string, BOOL ket_ends, uschar **left,
3589 BOOL skipping, BOOL honour_dollar)
3590 {
3591 int ptr = 0;
3592 int size = Ustrlen(string)+ 64;
3593 int item_type;
3594 uschar *yield = store_get(size);
3595 uschar *s = string;
3596 uschar *save_expand_nstring[EXPAND_MAXN+1];
3597 int save_expand_nlength[EXPAND_MAXN+1];
3598 BOOL resetok = TRUE;
3599
3600 expand_string_forcedfail = FALSE;
3601 expand_string_message = US"";
3602
3603 while (*s != 0)
3604 {
3605 uschar *value;
3606 uschar name[256];
3607
3608 /* \ escapes the next character, which must exist, or else
3609 the expansion fails. There's a special escape, \N, which causes
3610 copying of the subject verbatim up to the next \N. Otherwise,
3611 the escapes are the standard set. */
3612
3613 if (*s == '\\')
3614 {
3615 if (s[1] == 0)
3616 {
3617 expand_string_message = US"\\ at end of string";
3618 goto EXPAND_FAILED;
3619 }
3620
3621 if (s[1] == 'N')
3622 {
3623 uschar *t = s + 2;
3624 for (s = t; *s != 0; s++) if (*s == '\\' && s[1] == 'N') break;
3625 yield = string_cat(yield, &size, &ptr, t, s - t);
3626 if (*s != 0) s += 2;
3627 }
3628
3629 else
3630 {
3631 uschar ch[1];
3632 ch[0] = string_interpret_escape(&s);
3633 s++;
3634 yield = string_cat(yield, &size, &ptr, ch, 1);
3635 }
3636
3637 continue;
3638 }
3639
3640 /* Anything other than $ is just copied verbatim, unless we are
3641 looking for a terminating } character. */
3642
3643 if (ket_ends && *s == '}') break;
3644
3645 if (*s != '$' || !honour_dollar)
3646 {
3647 yield = string_cat(yield, &size, &ptr, s++, 1);
3648 continue;
3649 }
3650
3651 /* No { after the $ - must be a plain name or a number for string
3652 match variable. There has to be a fudge for variables that are the
3653 names of header fields preceded by "$header_" because header field
3654 names can contain any printing characters except space and colon.
3655 For those that don't like typing this much, "$h_" is a synonym for
3656 "$header_". A non-existent header yields a NULL value; nothing is
3657 inserted. */
3658
3659 if (isalpha((*(++s))))
3660 {
3661 int len;
3662 int newsize = 0;
3663
3664 s = read_name(name, sizeof(name), s, US"_");
3665
3666 /* If this is the first thing to be expanded, release the pre-allocated
3667 buffer. */
3668
3669 if (ptr == 0 && yield != NULL)
3670 {
3671 if (resetok) store_reset(yield);
3672 yield = NULL;
3673 size = 0;
3674 }
3675
3676 /* Header */
3677
3678 if (Ustrncmp(name, "h_", 2) == 0 ||
3679 Ustrncmp(name, "rh_", 3) == 0 ||
3680 Ustrncmp(name, "bh_", 3) == 0 ||
3681 Ustrncmp(name, "header_", 7) == 0 ||
3682 Ustrncmp(name, "rheader_", 8) == 0 ||
3683 Ustrncmp(name, "bheader_", 8) == 0)
3684 {
3685 BOOL want_raw = (name[0] == 'r')? TRUE : FALSE;
3686 uschar *charset = (name[0] == 'b')? NULL : headers_charset;
3687 s = read_header_name(name, sizeof(name), s);
3688 value = find_header(name, FALSE, &newsize, want_raw, charset);
3689
3690 /* If we didn't find the header, and the header contains a closing brace
3691 character, this may be a user error where the terminating colon
3692 has been omitted. Set a flag to adjust the error message in this case.
3693 But there is no error here - nothing gets inserted. */
3694
3695 if (value == NULL)
3696 {
3697 if (Ustrchr(name, '}') != NULL) malformed_header = TRUE;
3698 continue;
3699 }
3700 }
3701
3702 /* Variable */
3703
3704 else
3705 {
3706 value = find_variable(name, FALSE, skipping, &newsize);
3707 if (value == NULL)
3708 {
3709 expand_string_message =
3710 string_sprintf("unknown variable name \"%s\"", name);
3711 check_variable_error_message(name);
3712 goto EXPAND_FAILED;
3713 }
3714 }
3715
3716 /* If the data is known to be in a new buffer, newsize will be set to the
3717 size of that buffer. If this is the first thing in an expansion string,
3718 yield will be NULL; just point it at the new store instead of copying. Many
3719 expansion strings contain just one reference, so this is a useful
3720 optimization, especially for humungous headers. */
3721
3722 len = Ustrlen(value);
3723 if (yield == NULL && newsize != 0)
3724 {
3725 yield = value;
3726 size = newsize;
3727 ptr = len;
3728 }
3729 else yield = string_cat(yield, &size, &ptr, value, len);
3730
3731 continue;
3732 }
3733
3734 if (isdigit(*s))
3735 {
3736 int n;
3737 s = read_number(&n, s);
3738 if (n >= 0 && n <= expand_nmax)
3739 yield = string_cat(yield, &size, &ptr, expand_nstring[n],
3740 expand_nlength[n]);
3741 continue;
3742 }
3743
3744 /* Otherwise, if there's no '{' after $ it's an error. */
3745
3746 if (*s != '{')
3747 {
3748 expand_string_message = US"$ not followed by letter, digit, or {";
3749 goto EXPAND_FAILED;
3750 }
3751
3752 /* After { there can be various things, but they all start with
3753 an initial word, except for a number for a string match variable. */
3754
3755 if (isdigit((*(++s))))
3756 {
3757 int n;
3758 s = read_number(&n, s);
3759 if (*s++ != '}')
3760 {
3761 expand_string_message = US"} expected after number";
3762 goto EXPAND_FAILED;
3763 }
3764 if (n >= 0 && n <= expand_nmax)
3765 yield = string_cat(yield, &size, &ptr, expand_nstring[n],
3766 expand_nlength[n]);
3767 continue;
3768 }
3769
3770 if (!isalpha(*s))
3771 {
3772 expand_string_message = US"letter or digit expected after ${";
3773 goto EXPAND_FAILED;
3774 }
3775
3776 /* Allow "-" in names to cater for substrings with negative
3777 arguments. Since we are checking for known names after { this is
3778 OK. */
3779
3780 s = read_name(name, sizeof(name), s, US"_-");
3781 item_type = chop_match(name, item_table, sizeof(item_table)/sizeof(uschar *));
3782
3783 switch(item_type)
3784 {
3785 /* Call an ACL from an expansion. We feed data in via $acl_arg1 - $acl_arg9.
3786 If the ACL returns accept or reject we return content set by "message ="
3787 There is currently no limit on recursion; this would have us call
3788 acl_check_internal() directly and get a current level from somewhere.
3789 See also the acl expansion condition ECOND_ACL and the traditional
3790 acl modifier ACLC_ACL.
3791 Assume that the function has side-effects on the store that must be preserved.
3792 */
3793
3794 case EITEM_ACL:
3795 /* ${acl {name} {arg1}{arg2}...} */
3796 {
3797 uschar *sub[10]; /* name + arg1-arg9 (which must match number of acl_arg[]) */
3798 uschar *user_msg;
3799
3800 switch(read_subs(sub, 10, 1, &s, skipping, TRUE, US"acl"))
3801 {
3802 case 1: goto EXPAND_FAILED_CURLY;
3803 case 2:
3804 case 3: goto EXPAND_FAILED;
3805 }
3806 if (skipping) continue;
3807
3808 resetok = FALSE;
3809 switch(eval_acl(sub, sizeof(sub)/sizeof(*sub), &user_msg))
3810 {
3811 case OK:
3812 case FAIL:
3813 if (user_msg)
3814 yield = string_cat(yield, &size, &ptr, user_msg, Ustrlen(user_msg));
3815 continue;
3816
3817 case DEFER:
3818 expand_string_forcedfail = TRUE;
3819 default:
3820 expand_string_message = string_sprintf("error from acl \"%s\"", sub[0]);
3821 goto EXPAND_FAILED;
3822 }
3823 }
3824
3825 /* Handle conditionals - preserve the values of the numerical expansion
3826 variables in case they get changed by a regular expression match in the
3827 condition. If not, they retain their external settings. At the end
3828 of this "if" section, they get restored to their previous values. */
3829
3830 case EITEM_IF:
3831 {
3832 BOOL cond = FALSE;
3833 uschar *next_s;
3834 int save_expand_nmax =
3835 save_expand_strings(save_expand_nstring, save_expand_nlength);
3836
3837 while (isspace(*s)) s++;
3838 next_s = eval_condition(s, skipping? NULL : &cond);
3839 if (next_s == NULL) goto EXPAND_FAILED; /* message already set */
3840
3841 DEBUG(D_expand)
3842 debug_printf("condition: %.*s\n result: %s\n", (int)(next_s - s), s,
3843 cond? "true" : "false");
3844
3845 s = next_s;
3846
3847 /* The handling of "yes" and "no" result strings is now in a separate
3848 function that is also used by ${lookup} and ${extract} and ${run}. */
3849
3850 switch(process_yesno(
3851 skipping, /* were previously skipping */
3852 cond, /* success/failure indicator */
3853 lookup_value, /* value to reset for string2 */
3854 &s, /* input pointer */
3855 &yield, /* output pointer */
3856 &size, /* output size */
3857 &ptr, /* output current point */
3858 US"if")) /* condition type */
3859 {
3860 case 1: goto EXPAND_FAILED; /* when all is well, the */
3861 case 2: goto EXPAND_FAILED_CURLY; /* returned value is 0 */
3862 }
3863
3864 /* Restore external setting of expansion variables for continuation
3865 at this level. */
3866
3867 restore_expand_strings(save_expand_nmax, save_expand_nstring,
3868 save_expand_nlength);
3869 continue;
3870 }
3871
3872 /* Handle database lookups unless locked out. If "skipping" is TRUE, we are
3873 expanding an internal string that isn't actually going to be used. All we
3874 need to do is check the syntax, so don't do a lookup at all. Preserve the
3875 values of the numerical expansion variables in case they get changed by a
3876 partial lookup. If not, they retain their external settings. At the end
3877 of this "lookup" section, they get restored to their previous values. */
3878
3879 case EITEM_LOOKUP:
3880 {
3881 int stype, partial, affixlen, starflags;
3882 int expand_setup = 0;
3883 int nameptr = 0;
3884 uschar *key, *filename, *affix;
3885 uschar *save_lookup_value = lookup_value;
3886 int save_expand_nmax =
3887 save_expand_strings(save_expand_nstring, save_expand_nlength);
3888
3889 if ((expand_forbid & RDO_LOOKUP) != 0)
3890 {
3891 expand_string_message = US"lookup expansions are not permitted";
3892 goto EXPAND_FAILED;
3893 }
3894
3895 /* Get the key we are to look up for single-key+file style lookups.
3896 Otherwise set the key NULL pro-tem. */
3897
3898 while (isspace(*s)) s++;
3899 if (*s == '{')
3900 {
3901 key = expand_string_internal(s+1, TRUE, &s, skipping, TRUE);
3902 if (key == NULL) goto EXPAND_FAILED;
3903 if (*s++ != '}') goto EXPAND_FAILED_CURLY;
3904 while (isspace(*s)) s++;
3905 }
3906 else key = NULL;
3907
3908 /* Find out the type of database */
3909
3910 if (!isalpha(*s))
3911 {
3912 expand_string_message = US"missing lookup type";
3913 goto EXPAND_FAILED;
3914 }
3915
3916 /* The type is a string that may contain special characters of various
3917 kinds. Allow everything except space or { to appear; the actual content
3918 is checked by search_findtype_partial. */
3919
3920 while (*s != 0 && *s != '{' && !isspace(*s))
3921 {
3922 if (nameptr < sizeof(name) - 1) name[nameptr++] = *s;
3923 s++;
3924 }
3925 name[nameptr] = 0;
3926 while (isspace(*s)) s++;
3927
3928 /* Now check for the individual search type and any partial or default
3929 options. Only those types that are actually in the binary are valid. */
3930
3931 stype = search_findtype_partial(name, &partial, &affix, &affixlen,
3932 &starflags);
3933 if (stype < 0)
3934 {
3935 expand_string_message = search_error_message;
3936 goto EXPAND_FAILED;
3937 }
3938
3939 /* Check that a key was provided for those lookup types that need it,
3940 and was not supplied for those that use the query style. */
3941
3942 if (!mac_islookup(stype, lookup_querystyle|lookup_absfilequery))
3943 {
3944 if (key == NULL)
3945 {
3946 expand_string_message = string_sprintf("missing {key} for single-"
3947 "key \"%s\" lookup", name);
3948 goto EXPAND_FAILED;
3949 }
3950 }
3951 else
3952 {
3953 if (key != NULL)
3954 {
3955 expand_string_message = string_sprintf("a single key was given for "
3956 "lookup type \"%s\", which is not a single-key lookup type", name