a3dc590cce982033c0b08353e6e2eb2a760d92ac
[exim.git] / src / src / expand.c
1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
4
5 /* Copyright (c) University of Cambridge 1995 - 2009 */
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"dlfunc",
106 US"extract",
107 US"filter",
108 US"hash",
109 US"hmac",
110 US"if",
111 US"length",
112 US"lookup",
113 US"map",
114 US"nhash",
115 US"perl",
116 US"prvs",
117 US"prvscheck",
118 US"readfile",
119 US"readsocket",
120 US"reduce",
121 US"run",
122 US"sg",
123 US"substr",
124 US"tr" };
125
126 enum {
127 EITEM_DLFUNC,
128 EITEM_EXTRACT,
129 EITEM_FILTER,
130 EITEM_HASH,
131 EITEM_HMAC,
132 EITEM_IF,
133 EITEM_LENGTH,
134 EITEM_LOOKUP,
135 EITEM_MAP,
136 EITEM_NHASH,
137 EITEM_PERL,
138 EITEM_PRVS,
139 EITEM_PRVSCHECK,
140 EITEM_READFILE,
141 EITEM_READSOCK,
142 EITEM_REDUCE,
143 EITEM_RUN,
144 EITEM_SG,
145 EITEM_SUBSTR,
146 EITEM_TR };
147
148 /* Tables of operator names, and corresponding switch numbers. The names must be
149 in alphabetical order. There are two tables, because underscore is used in some
150 cases to introduce arguments, whereas for other it is part of the name. This is
151 an historical mis-design. */
152
153 static uschar *op_table_underscore[] = {
154 US"from_utf8",
155 US"local_part",
156 US"quote_local_part",
157 US"reverse_ip",
158 US"time_eval",
159 US"time_interval"};
160
161 enum {
162 EOP_FROM_UTF8,
163 EOP_LOCAL_PART,
164 EOP_QUOTE_LOCAL_PART,
165 EOP_REVERSE_IP,
166 EOP_TIME_EVAL,
167 EOP_TIME_INTERVAL };
168
169 static uschar *op_table_main[] = {
170 US"address",
171 US"addresses",
172 US"base62",
173 US"base62d",
174 US"domain",
175 US"escape",
176 US"eval",
177 US"eval10",
178 US"expand",
179 US"h",
180 US"hash",
181 US"hex2b64",
182 US"l",
183 US"lc",
184 US"length",
185 US"mask",
186 US"md5",
187 US"nh",
188 US"nhash",
189 US"quote",
190 US"randint",
191 US"rfc2047",
192 US"rfc2047d",
193 US"rxquote",
194 US"s",
195 US"sha1",
196 US"stat",
197 US"str2b64",
198 US"strlen",
199 US"substr",
200 US"uc" };
201
202 enum {
203 EOP_ADDRESS = sizeof(op_table_underscore)/sizeof(uschar *),
204 EOP_ADDRESSES,
205 EOP_BASE62,
206 EOP_BASE62D,
207 EOP_DOMAIN,
208 EOP_ESCAPE,
209 EOP_EVAL,
210 EOP_EVAL10,
211 EOP_EXPAND,
212 EOP_H,
213 EOP_HASH,
214 EOP_HEX2B64,
215 EOP_L,
216 EOP_LC,
217 EOP_LENGTH,
218 EOP_MASK,
219 EOP_MD5,
220 EOP_NH,
221 EOP_NHASH,
222 EOP_QUOTE,
223 EOP_RANDINT,
224 EOP_RFC2047,
225 EOP_RFC2047D,
226 EOP_RXQUOTE,
227 EOP_S,
228 EOP_SHA1,
229 EOP_STAT,
230 EOP_STR2B64,
231 EOP_STRLEN,
232 EOP_SUBSTR,
233 EOP_UC };
234
235
236 /* Table of condition names, and corresponding switch numbers. The names must
237 be in alphabetical order. */
238
239 static uschar *cond_table[] = {
240 US"<",
241 US"<=",
242 US"=",
243 US"==", /* Backward compatibility */
244 US">",
245 US">=",
246 US"and",
247 US"bool",
248 US"bool_lax",
249 US"crypteq",
250 US"def",
251 US"eq",
252 US"eqi",
253 US"exists",
254 US"first_delivery",
255 US"forall",
256 US"forany",
257 US"ge",
258 US"gei",
259 US"gt",
260 US"gti",
261 US"inlist",
262 US"inlisti",
263 US"isip",
264 US"isip4",
265 US"isip6",
266 US"ldapauth",
267 US"le",
268 US"lei",
269 US"lt",
270 US"lti",
271 US"match",
272 US"match_address",
273 US"match_domain",
274 US"match_ip",
275 US"match_local_part",
276 US"or",
277 US"pam",
278 US"pwcheck",
279 US"queue_running",
280 US"radius",
281 US"saslauthd"
282 };
283
284 enum {
285 ECOND_NUM_L,
286 ECOND_NUM_LE,
287 ECOND_NUM_E,
288 ECOND_NUM_EE,
289 ECOND_NUM_G,
290 ECOND_NUM_GE,
291 ECOND_AND,
292 ECOND_BOOL,
293 ECOND_BOOL_LAX,
294 ECOND_CRYPTEQ,
295 ECOND_DEF,
296 ECOND_STR_EQ,
297 ECOND_STR_EQI,
298 ECOND_EXISTS,
299 ECOND_FIRST_DELIVERY,
300 ECOND_FORALL,
301 ECOND_FORANY,
302 ECOND_STR_GE,
303 ECOND_STR_GEI,
304 ECOND_STR_GT,
305 ECOND_STR_GTI,
306 ECOND_INLIST,
307 ECOND_INLISTI,
308 ECOND_ISIP,
309 ECOND_ISIP4,
310 ECOND_ISIP6,
311 ECOND_LDAPAUTH,
312 ECOND_STR_LE,
313 ECOND_STR_LEI,
314 ECOND_STR_LT,
315 ECOND_STR_LTI,
316 ECOND_MATCH,
317 ECOND_MATCH_ADDRESS,
318 ECOND_MATCH_DOMAIN,
319 ECOND_MATCH_IP,
320 ECOND_MATCH_LOCAL_PART,
321 ECOND_OR,
322 ECOND_PAM,
323 ECOND_PWCHECK,
324 ECOND_QUEUE_RUNNING,
325 ECOND_RADIUS,
326 ECOND_SASLAUTHD
327 };
328
329
330 /* Type for main variable table */
331
332 typedef struct {
333 const char *name;
334 int type;
335 void *value;
336 } var_entry;
337
338 /* Type for entries pointing to address/length pairs. Not currently
339 in use. */
340
341 typedef struct {
342 uschar **address;
343 int *length;
344 } alblock;
345
346 /* Types of table entry */
347
348 enum {
349 vtype_int, /* value is address of int */
350 vtype_filter_int, /* ditto, but recognized only when filtering */
351 vtype_ino, /* value is address of ino_t (not always an int) */
352 vtype_uid, /* value is address of uid_t (not always an int) */
353 vtype_gid, /* value is address of gid_t (not always an int) */
354 vtype_stringptr, /* value is address of pointer to string */
355 vtype_msgbody, /* as stringptr, but read when first required */
356 vtype_msgbody_end, /* ditto, the end of the message */
357 vtype_msgheaders, /* the message's headers, processed */
358 vtype_msgheaders_raw, /* the message's headers, unprocessed */
359 vtype_localpart, /* extract local part from string */
360 vtype_domain, /* extract domain from string */
361 vtype_recipients, /* extract recipients from recipients list */
362 /* (available only in system filters, ACLs, and */
363 /* local_scan()) */
364 vtype_todbsdin, /* value not used; generate BSD inbox tod */
365 vtype_tode, /* value not used; generate tod in epoch format */
366 vtype_todf, /* value not used; generate full tod */
367 vtype_todl, /* value not used; generate log tod */
368 vtype_todlf, /* value not used; generate log file datestamp tod */
369 vtype_todzone, /* value not used; generate time zone only */
370 vtype_todzulu, /* value not used; generate zulu tod */
371 vtype_reply, /* value not used; get reply from headers */
372 vtype_pid, /* value not used; result is pid */
373 vtype_host_lookup, /* value not used; get host name */
374 vtype_load_avg, /* value not used; result is int from os_getloadavg */
375 vtype_pspace, /* partition space; value is T/F for spool/log */
376 vtype_pinodes /* partition inodes; value is T/F for spool/log */
377 #ifndef DISABLE_DKIM
378 ,vtype_dkim /* Lookup of value in DKIM signature */
379 #endif
380 };
381
382 /* This table must be kept in alphabetical order. */
383
384 static var_entry var_table[] = {
385 /* WARNING: Do not invent variables whose names start acl_c or acl_m because
386 they will be confused with user-creatable ACL variables. */
387 { "acl_verify_message", vtype_stringptr, &acl_verify_message },
388 { "address_data", vtype_stringptr, &deliver_address_data },
389 { "address_file", vtype_stringptr, &address_file },
390 { "address_pipe", vtype_stringptr, &address_pipe },
391 { "authenticated_id", vtype_stringptr, &authenticated_id },
392 { "authenticated_sender",vtype_stringptr, &authenticated_sender },
393 { "authentication_failed",vtype_int, &authentication_failed },
394 #ifdef WITH_CONTENT_SCAN
395 { "av_failed", vtype_int, &av_failed },
396 #endif
397 #ifdef EXPERIMENTAL_BRIGHTMAIL
398 { "bmi_alt_location", vtype_stringptr, &bmi_alt_location },
399 { "bmi_base64_tracker_verdict", vtype_stringptr, &bmi_base64_tracker_verdict },
400 { "bmi_base64_verdict", vtype_stringptr, &bmi_base64_verdict },
401 { "bmi_deliver", vtype_int, &bmi_deliver },
402 #endif
403 { "body_linecount", vtype_int, &body_linecount },
404 { "body_zerocount", vtype_int, &body_zerocount },
405 { "bounce_recipient", vtype_stringptr, &bounce_recipient },
406 { "bounce_return_size_limit", vtype_int, &bounce_return_size_limit },
407 { "caller_gid", vtype_gid, &real_gid },
408 { "caller_uid", vtype_uid, &real_uid },
409 { "compile_date", vtype_stringptr, &version_date },
410 { "compile_number", vtype_stringptr, &version_cnumber },
411 { "csa_status", vtype_stringptr, &csa_status },
412 #ifdef EXPERIMENTAL_DCC
413 { "dcc_header", vtype_stringptr, &dcc_header },
414 { "dcc_result", vtype_stringptr, &dcc_result },
415 #endif
416 #ifdef WITH_OLD_DEMIME
417 { "demime_errorlevel", vtype_int, &demime_errorlevel },
418 { "demime_reason", vtype_stringptr, &demime_reason },
419 #endif
420 #ifndef DISABLE_DKIM
421 { "dkim_algo", vtype_dkim, (void *)DKIM_ALGO },
422 { "dkim_bodylength", vtype_dkim, (void *)DKIM_BODYLENGTH },
423 { "dkim_canon_body", vtype_dkim, (void *)DKIM_CANON_BODY },
424 { "dkim_canon_headers", vtype_dkim, (void *)DKIM_CANON_HEADERS },
425 { "dkim_copiedheaders", vtype_dkim, (void *)DKIM_COPIEDHEADERS },
426 { "dkim_created", vtype_dkim, (void *)DKIM_CREATED },
427 { "dkim_cur_signer", vtype_stringptr, &dkim_cur_signer },
428 { "dkim_domain", vtype_stringptr, &dkim_signing_domain },
429 { "dkim_expires", vtype_dkim, (void *)DKIM_EXPIRES },
430 { "dkim_headernames", vtype_dkim, (void *)DKIM_HEADERNAMES },
431 { "dkim_identity", vtype_dkim, (void *)DKIM_IDENTITY },
432 { "dkim_key_granularity",vtype_dkim, (void *)DKIM_KEY_GRANULARITY },
433 { "dkim_key_nosubdomains",vtype_dkim, (void *)DKIM_NOSUBDOMAINS },
434 { "dkim_key_notes", vtype_dkim, (void *)DKIM_KEY_NOTES },
435 { "dkim_key_srvtype", vtype_dkim, (void *)DKIM_KEY_SRVTYPE },
436 { "dkim_key_testing", vtype_dkim, (void *)DKIM_KEY_TESTING },
437 { "dkim_selector", vtype_stringptr, &dkim_signing_selector },
438 { "dkim_signers", vtype_stringptr, &dkim_signers },
439 { "dkim_verify_reason", vtype_dkim, (void *)DKIM_VERIFY_REASON },
440 { "dkim_verify_status", vtype_dkim, (void *)DKIM_VERIFY_STATUS},
441 #endif
442 { "dnslist_domain", vtype_stringptr, &dnslist_domain },
443 { "dnslist_matched", vtype_stringptr, &dnslist_matched },
444 { "dnslist_text", vtype_stringptr, &dnslist_text },
445 { "dnslist_value", vtype_stringptr, &dnslist_value },
446 { "domain", vtype_stringptr, &deliver_domain },
447 { "domain_data", vtype_stringptr, &deliver_domain_data },
448 { "exim_gid", vtype_gid, &exim_gid },
449 { "exim_path", vtype_stringptr, &exim_path },
450 { "exim_uid", vtype_uid, &exim_uid },
451 #ifdef WITH_OLD_DEMIME
452 { "found_extension", vtype_stringptr, &found_extension },
453 #endif
454 { "home", vtype_stringptr, &deliver_home },
455 { "host", vtype_stringptr, &deliver_host },
456 { "host_address", vtype_stringptr, &deliver_host_address },
457 { "host_data", vtype_stringptr, &host_data },
458 { "host_lookup_deferred",vtype_int, &host_lookup_deferred },
459 { "host_lookup_failed", vtype_int, &host_lookup_failed },
460 { "inode", vtype_ino, &deliver_inode },
461 { "interface_address", vtype_stringptr, &interface_address },
462 { "interface_port", vtype_int, &interface_port },
463 { "item", vtype_stringptr, &iterate_item },
464 #ifdef LOOKUP_LDAP
465 { "ldap_dn", vtype_stringptr, &eldap_dn },
466 #endif
467 { "load_average", vtype_load_avg, NULL },
468 { "local_part", vtype_stringptr, &deliver_localpart },
469 { "local_part_data", vtype_stringptr, &deliver_localpart_data },
470 { "local_part_prefix", vtype_stringptr, &deliver_localpart_prefix },
471 { "local_part_suffix", vtype_stringptr, &deliver_localpart_suffix },
472 { "local_scan_data", vtype_stringptr, &local_scan_data },
473 { "local_user_gid", vtype_gid, &local_user_gid },
474 { "local_user_uid", vtype_uid, &local_user_uid },
475 { "localhost_number", vtype_int, &host_number },
476 { "log_inodes", vtype_pinodes, (void *)FALSE },
477 { "log_space", vtype_pspace, (void *)FALSE },
478 { "mailstore_basename", vtype_stringptr, &mailstore_basename },
479 #ifdef WITH_CONTENT_SCAN
480 { "malware_name", vtype_stringptr, &malware_name },
481 #endif
482 { "max_received_linelength", vtype_int, &max_received_linelength },
483 { "message_age", vtype_int, &message_age },
484 { "message_body", vtype_msgbody, &message_body },
485 { "message_body_end", vtype_msgbody_end, &message_body_end },
486 { "message_body_size", vtype_int, &message_body_size },
487 { "message_exim_id", vtype_stringptr, &message_id },
488 { "message_headers", vtype_msgheaders, NULL },
489 { "message_headers_raw", vtype_msgheaders_raw, NULL },
490 { "message_id", vtype_stringptr, &message_id },
491 { "message_linecount", vtype_int, &message_linecount },
492 { "message_size", vtype_int, &message_size },
493 #ifdef WITH_CONTENT_SCAN
494 { "mime_anomaly_level", vtype_int, &mime_anomaly_level },
495 { "mime_anomaly_text", vtype_stringptr, &mime_anomaly_text },
496 { "mime_boundary", vtype_stringptr, &mime_boundary },
497 { "mime_charset", vtype_stringptr, &mime_charset },
498 { "mime_content_description", vtype_stringptr, &mime_content_description },
499 { "mime_content_disposition", vtype_stringptr, &mime_content_disposition },
500 { "mime_content_id", vtype_stringptr, &mime_content_id },
501 { "mime_content_size", vtype_int, &mime_content_size },
502 { "mime_content_transfer_encoding",vtype_stringptr, &mime_content_transfer_encoding },
503 { "mime_content_type", vtype_stringptr, &mime_content_type },
504 { "mime_decoded_filename", vtype_stringptr, &mime_decoded_filename },
505 { "mime_filename", vtype_stringptr, &mime_filename },
506 { "mime_is_coverletter", vtype_int, &mime_is_coverletter },
507 { "mime_is_multipart", vtype_int, &mime_is_multipart },
508 { "mime_is_rfc822", vtype_int, &mime_is_rfc822 },
509 { "mime_part_count", vtype_int, &mime_part_count },
510 #endif
511 { "n0", vtype_filter_int, &filter_n[0] },
512 { "n1", vtype_filter_int, &filter_n[1] },
513 { "n2", vtype_filter_int, &filter_n[2] },
514 { "n3", vtype_filter_int, &filter_n[3] },
515 { "n4", vtype_filter_int, &filter_n[4] },
516 { "n5", vtype_filter_int, &filter_n[5] },
517 { "n6", vtype_filter_int, &filter_n[6] },
518 { "n7", vtype_filter_int, &filter_n[7] },
519 { "n8", vtype_filter_int, &filter_n[8] },
520 { "n9", vtype_filter_int, &filter_n[9] },
521 { "original_domain", vtype_stringptr, &deliver_domain_orig },
522 { "original_local_part", vtype_stringptr, &deliver_localpart_orig },
523 { "originator_gid", vtype_gid, &originator_gid },
524 { "originator_uid", vtype_uid, &originator_uid },
525 { "parent_domain", vtype_stringptr, &deliver_domain_parent },
526 { "parent_local_part", vtype_stringptr, &deliver_localpart_parent },
527 { "pid", vtype_pid, NULL },
528 { "primary_hostname", vtype_stringptr, &primary_hostname },
529 { "prvscheck_address", vtype_stringptr, &prvscheck_address },
530 { "prvscheck_keynum", vtype_stringptr, &prvscheck_keynum },
531 { "prvscheck_result", vtype_stringptr, &prvscheck_result },
532 { "qualify_domain", vtype_stringptr, &qualify_domain_sender },
533 { "qualify_recipient", vtype_stringptr, &qualify_domain_recipient },
534 { "rcpt_count", vtype_int, &rcpt_count },
535 { "rcpt_defer_count", vtype_int, &rcpt_defer_count },
536 { "rcpt_fail_count", vtype_int, &rcpt_fail_count },
537 { "received_count", vtype_int, &received_count },
538 { "received_for", vtype_stringptr, &received_for },
539 { "received_ip_address", vtype_stringptr, &interface_address },
540 { "received_port", vtype_int, &interface_port },
541 { "received_protocol", vtype_stringptr, &received_protocol },
542 { "received_time", vtype_int, &received_time },
543 { "recipient_data", vtype_stringptr, &recipient_data },
544 { "recipient_verify_failure",vtype_stringptr,&recipient_verify_failure },
545 { "recipients", vtype_recipients, NULL },
546 { "recipients_count", vtype_int, &recipients_count },
547 #ifdef WITH_CONTENT_SCAN
548 { "regex_match_string", vtype_stringptr, &regex_match_string },
549 #endif
550 { "reply_address", vtype_reply, NULL },
551 { "return_path", vtype_stringptr, &return_path },
552 { "return_size_limit", vtype_int, &bounce_return_size_limit },
553 { "runrc", vtype_int, &runrc },
554 { "self_hostname", vtype_stringptr, &self_hostname },
555 { "sender_address", vtype_stringptr, &sender_address },
556 { "sender_address_data", vtype_stringptr, &sender_address_data },
557 { "sender_address_domain", vtype_domain, &sender_address },
558 { "sender_address_local_part", vtype_localpart, &sender_address },
559 { "sender_data", vtype_stringptr, &sender_data },
560 { "sender_fullhost", vtype_stringptr, &sender_fullhost },
561 { "sender_helo_name", vtype_stringptr, &sender_helo_name },
562 { "sender_host_address", vtype_stringptr, &sender_host_address },
563 { "sender_host_authenticated",vtype_stringptr, &sender_host_authenticated },
564 { "sender_host_name", vtype_host_lookup, NULL },
565 { "sender_host_port", vtype_int, &sender_host_port },
566 { "sender_ident", vtype_stringptr, &sender_ident },
567 { "sender_rate", vtype_stringptr, &sender_rate },
568 { "sender_rate_limit", vtype_stringptr, &sender_rate_limit },
569 { "sender_rate_period", vtype_stringptr, &sender_rate_period },
570 { "sender_rcvhost", vtype_stringptr, &sender_rcvhost },
571 { "sender_verify_failure",vtype_stringptr, &sender_verify_failure },
572 { "sending_ip_address", vtype_stringptr, &sending_ip_address },
573 { "sending_port", vtype_int, &sending_port },
574 { "smtp_active_hostname", vtype_stringptr, &smtp_active_hostname },
575 { "smtp_command", vtype_stringptr, &smtp_cmd_buffer },
576 { "smtp_command_argument", vtype_stringptr, &smtp_cmd_argument },
577 { "smtp_count_at_connection_start", vtype_int, &smtp_accept_count },
578 { "smtp_notquit_reason", vtype_stringptr, &smtp_notquit_reason },
579 { "sn0", vtype_filter_int, &filter_sn[0] },
580 { "sn1", vtype_filter_int, &filter_sn[1] },
581 { "sn2", vtype_filter_int, &filter_sn[2] },
582 { "sn3", vtype_filter_int, &filter_sn[3] },
583 { "sn4", vtype_filter_int, &filter_sn[4] },
584 { "sn5", vtype_filter_int, &filter_sn[5] },
585 { "sn6", vtype_filter_int, &filter_sn[6] },
586 { "sn7", vtype_filter_int, &filter_sn[7] },
587 { "sn8", vtype_filter_int, &filter_sn[8] },
588 { "sn9", vtype_filter_int, &filter_sn[9] },
589 #ifdef WITH_CONTENT_SCAN
590 { "spam_bar", vtype_stringptr, &spam_bar },
591 { "spam_report", vtype_stringptr, &spam_report },
592 { "spam_score", vtype_stringptr, &spam_score },
593 { "spam_score_int", vtype_stringptr, &spam_score_int },
594 #endif
595 #ifdef EXPERIMENTAL_SPF
596 { "spf_guess", vtype_stringptr, &spf_guess },
597 { "spf_header_comment", vtype_stringptr, &spf_header_comment },
598 { "spf_received", vtype_stringptr, &spf_received },
599 { "spf_result", vtype_stringptr, &spf_result },
600 { "spf_smtp_comment", vtype_stringptr, &spf_smtp_comment },
601 #endif
602 { "spool_directory", vtype_stringptr, &spool_directory },
603 { "spool_inodes", vtype_pinodes, (void *)TRUE },
604 { "spool_space", vtype_pspace, (void *)TRUE },
605 #ifdef EXPERIMENTAL_SRS
606 { "srs_db_address", vtype_stringptr, &srs_db_address },
607 { "srs_db_key", vtype_stringptr, &srs_db_key },
608 { "srs_orig_recipient", vtype_stringptr, &srs_orig_recipient },
609 { "srs_orig_sender", vtype_stringptr, &srs_orig_sender },
610 { "srs_recipient", vtype_stringptr, &srs_recipient },
611 { "srs_status", vtype_stringptr, &srs_status },
612 #endif
613 { "thisaddress", vtype_stringptr, &filter_thisaddress },
614 { "tls_certificate_verified", vtype_int, &tls_certificate_verified },
615 { "tls_cipher", vtype_stringptr, &tls_cipher },
616 { "tls_peerdn", vtype_stringptr, &tls_peerdn },
617 { "tod_bsdinbox", vtype_todbsdin, NULL },
618 { "tod_epoch", vtype_tode, NULL },
619 { "tod_full", vtype_todf, NULL },
620 { "tod_log", vtype_todl, NULL },
621 { "tod_logfile", vtype_todlf, NULL },
622 { "tod_zone", vtype_todzone, NULL },
623 { "tod_zulu", vtype_todzulu, NULL },
624 { "value", vtype_stringptr, &lookup_value },
625 { "version_number", vtype_stringptr, &version_string },
626 { "warn_message_delay", vtype_stringptr, &warnmsg_delay },
627 { "warn_message_recipient",vtype_stringptr, &warnmsg_recipients },
628 { "warn_message_recipients",vtype_stringptr,&warnmsg_recipients },
629 { "warnmsg_delay", vtype_stringptr, &warnmsg_delay },
630 { "warnmsg_recipient", vtype_stringptr, &warnmsg_recipients },
631 { "warnmsg_recipients", vtype_stringptr, &warnmsg_recipients }
632 };
633
634 static int var_table_size = sizeof(var_table)/sizeof(var_entry);
635 static uschar var_buffer[256];
636 static BOOL malformed_header;
637
638 /* For textual hashes */
639
640 static const char *hashcodes = "abcdefghijklmnopqrtsuvwxyz"
641 "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
642 "0123456789";
643
644 enum { HMAC_MD5, HMAC_SHA1 };
645
646 /* For numeric hashes */
647
648 static unsigned int prime[] = {
649 2, 3, 5, 7, 11, 13, 17, 19, 23, 29,
650 31, 37, 41, 43, 47, 53, 59, 61, 67, 71,
651 73, 79, 83, 89, 97, 101, 103, 107, 109, 113};
652
653 /* For printing modes in symbolic form */
654
655 static uschar *mtable_normal[] =
656 { US"---", US"--x", US"-w-", US"-wx", US"r--", US"r-x", US"rw-", US"rwx" };
657
658 static uschar *mtable_setid[] =
659 { US"--S", US"--s", US"-wS", US"-ws", US"r-S", US"r-s", US"rwS", US"rws" };
660
661 static uschar *mtable_sticky[] =
662 { US"--T", US"--t", US"-wT", US"-wt", US"r-T", US"r-t", US"rwT", US"rwt" };
663
664
665
666 /*************************************************
667 * Tables for UTF-8 support *
668 *************************************************/
669
670 /* Table of the number of extra characters, indexed by the first character
671 masked with 0x3f. The highest number for a valid UTF-8 character is in fact
672 0x3d. */
673
674 static uschar utf8_table1[] = {
675 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
676 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
677 2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
678 3,3,3,3,3,3,3,3,4,4,4,4,5,5,5,5 };
679
680 /* These are the masks for the data bits in the first byte of a character,
681 indexed by the number of additional bytes. */
682
683 static int utf8_table2[] = { 0xff, 0x1f, 0x0f, 0x07, 0x03, 0x01};
684
685 /* Get the next UTF-8 character, advancing the pointer. */
686
687 #define GETUTF8INC(c, ptr) \
688 c = *ptr++; \
689 if ((c & 0xc0) == 0xc0) \
690 { \
691 int a = utf8_table1[c & 0x3f]; /* Number of additional bytes */ \
692 int s = 6*a; \
693 c = (c & utf8_table2[a]) << s; \
694 while (a-- > 0) \
695 { \
696 s -= 6; \
697 c |= (*ptr++ & 0x3f) << s; \
698 } \
699 }
700
701
702 /*************************************************
703 * Binary chop search on a table *
704 *************************************************/
705
706 /* This is used for matching expansion items and operators.
707
708 Arguments:
709 name the name that is being sought
710 table the table to search
711 table_size the number of items in the table
712
713 Returns: the offset in the table, or -1
714 */
715
716 static int
717 chop_match(uschar *name, uschar **table, int table_size)
718 {
719 uschar **bot = table;
720 uschar **top = table + table_size;
721
722 while (top > bot)
723 {
724 uschar **mid = bot + (top - bot)/2;
725 int c = Ustrcmp(name, *mid);
726 if (c == 0) return mid - table;
727 if (c > 0) bot = mid + 1; else top = mid;
728 }
729
730 return -1;
731 }
732
733
734
735 /*************************************************
736 * Check a condition string *
737 *************************************************/
738
739 /* This function is called to expand a string, and test the result for a "true"
740 or "false" value. Failure of the expansion yields FALSE; logged unless it was a
741 forced fail or lookup defer. All store used by the function can be released on
742 exit.
743
744 The actual false-value tests should be replicated for ECOND_BOOL_LAX.
745
746 Arguments:
747 condition the condition string
748 m1 text to be incorporated in panic error
749 m2 ditto
750
751 Returns: TRUE if condition is met, FALSE if not
752 */
753
754 BOOL
755 expand_check_condition(uschar *condition, uschar *m1, uschar *m2)
756 {
757 int rc;
758 void *reset_point = store_get(0);
759 uschar *ss = expand_string(condition);
760 if (ss == NULL)
761 {
762 if (!expand_string_forcedfail && !search_find_defer)
763 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand condition \"%s\" "
764 "for %s %s: %s", condition, m1, m2, expand_string_message);
765 return FALSE;
766 }
767 rc = ss[0] != 0 && Ustrcmp(ss, "0") != 0 && strcmpic(ss, US"no") != 0 &&
768 strcmpic(ss, US"false") != 0;
769 store_reset(reset_point);
770 return rc;
771 }
772
773
774
775 /*************************************************
776 * Pseudo-random number generation *
777 *************************************************/
778
779 /* Pseudo-random number generation. The result is not "expected" to be
780 cryptographically strong but not so weak that someone will shoot themselves
781 in the foot using it as a nonce in some email header scheme or whatever
782 weirdness they'll twist this into. The result should ideally handle fork().
783
784 However, if we're stuck unable to provide this, then we'll fall back to
785 appallingly bad randomness.
786
787 If SUPPORT_TLS is defined and OpenSSL is used, then this will not be used.
788 The GNUTLS randomness functions found do not seem amenable to extracting
789 random numbers outside of a TLS context. Any volunteers?
790
791 Arguments:
792 max range maximum
793 Returns a random number in range [0, max-1]
794 */
795
796 #if !defined(SUPPORT_TLS) || defined(USE_GNUTLS)
797 int
798 pseudo_random_number(int max)
799 {
800 static pid_t pid = 0;
801 pid_t p2;
802 #if defined(HAVE_SRANDOM) && !defined(HAVE_SRANDOMDEV)
803 struct timeval tv;
804 #endif
805
806 p2 = getpid();
807 if (p2 != pid)
808 {
809 if (pid != 0)
810 {
811
812 #ifdef HAVE_ARC4RANDOM
813 /* cryptographically strong randomness, common on *BSD platforms, not
814 so much elsewhere. Alas. */
815 arc4random_stir();
816 #elif defined(HAVE_SRANDOM) || defined(HAVE_SRANDOMDEV)
817 #ifdef HAVE_SRANDOMDEV
818 /* uses random(4) for seeding */
819 srandomdev();
820 #else
821 gettimeofday(&tv, NULL);
822 srandom(tv.tv_sec | tv.tv_usec | getpid());
823 #endif
824 #else
825 /* Poor randomness and no seeding here */
826 #endif
827
828 }
829 pid = p2;
830 }
831
832 #ifdef HAVE_ARC4RANDOM
833 return arc4random() % max;
834 #elif defined(HAVE_SRANDOM) || defined(HAVE_SRANDOMDEV)
835 return random() % max;
836 #else
837 /* This one returns a 16-bit number, definitely not crypto-strong */
838 return random_number(max);
839 #endif
840 }
841
842 #endif
843
844 /*************************************************
845 * Pick out a name from a string *
846 *************************************************/
847
848 /* If the name is too long, it is silently truncated.
849
850 Arguments:
851 name points to a buffer into which to put the name
852 max is the length of the buffer
853 s points to the first alphabetic character of the name
854 extras chars other than alphanumerics to permit
855
856 Returns: pointer to the first character after the name
857
858 Note: The test for *s != 0 in the while loop is necessary because
859 Ustrchr() yields non-NULL if the character is zero (which is not something
860 I expected). */
861
862 static uschar *
863 read_name(uschar *name, int max, uschar *s, uschar *extras)
864 {
865 int ptr = 0;
866 while (*s != 0 && (isalnum(*s) || Ustrchr(extras, *s) != NULL))
867 {
868 if (ptr < max-1) name[ptr++] = *s;
869 s++;
870 }
871 name[ptr] = 0;
872 return s;
873 }
874
875
876
877 /*************************************************
878 * Pick out the rest of a header name *
879 *************************************************/
880
881 /* A variable name starting $header_ (or just $h_ for those who like
882 abbreviations) might not be the complete header name because headers can
883 contain any printing characters in their names, except ':'. This function is
884 called to read the rest of the name, chop h[eader]_ off the front, and put ':'
885 on the end, if the name was terminated by white space.
886
887 Arguments:
888 name points to a buffer in which the name read so far exists
889 max is the length of the buffer
890 s points to the first character after the name so far, i.e. the
891 first non-alphameric character after $header_xxxxx
892
893 Returns: a pointer to the first character after the header name
894 */
895
896 static uschar *
897 read_header_name(uschar *name, int max, uschar *s)
898 {
899 int prelen = Ustrchr(name, '_') - name + 1;
900 int ptr = Ustrlen(name) - prelen;
901 if (ptr > 0) memmove(name, name+prelen, ptr);
902 while (mac_isgraph(*s) && *s != ':')
903 {
904 if (ptr < max-1) name[ptr++] = *s;
905 s++;
906 }
907 if (*s == ':') s++;
908 name[ptr++] = ':';
909 name[ptr] = 0;
910 return s;
911 }
912
913
914
915 /*************************************************
916 * Pick out a number from a string *
917 *************************************************/
918
919 /* Arguments:
920 n points to an integer into which to put the number
921 s points to the first digit of the number
922
923 Returns: a pointer to the character after the last digit
924 */
925
926 static uschar *
927 read_number(int *n, uschar *s)
928 {
929 *n = 0;
930 while (isdigit(*s)) *n = *n * 10 + (*s++ - '0');
931 return s;
932 }
933
934
935
936 /*************************************************
937 * Extract keyed subfield from a string *
938 *************************************************/
939
940 /* The yield is in dynamic store; NULL means that the key was not found.
941
942 Arguments:
943 key points to the name of the key
944 s points to the string from which to extract the subfield
945
946 Returns: NULL if the subfield was not found, or
947 a pointer to the subfield's data
948 */
949
950 static uschar *
951 expand_getkeyed(uschar *key, uschar *s)
952 {
953 int length = Ustrlen(key);
954 while (isspace(*s)) s++;
955
956 /* Loop to search for the key */
957
958 while (*s != 0)
959 {
960 int dkeylength;
961 uschar *data;
962 uschar *dkey = s;
963
964 while (*s != 0 && *s != '=' && !isspace(*s)) s++;
965 dkeylength = s - dkey;
966 while (isspace(*s)) s++;
967 if (*s == '=') while (isspace((*(++s))));
968
969 data = string_dequote(&s);
970 if (length == dkeylength && strncmpic(key, dkey, length) == 0)
971 return data;
972
973 while (isspace(*s)) s++;
974 }
975
976 return NULL;
977 }
978
979
980
981
982 /*************************************************
983 * Extract numbered subfield from string *
984 *************************************************/
985
986 /* Extracts a numbered field from a string that is divided by tokens - for
987 example a line from /etc/passwd is divided by colon characters. First field is
988 numbered one. Negative arguments count from the right. Zero returns the whole
989 string. Returns NULL if there are insufficient tokens in the string
990
991 ***WARNING***
992 Modifies final argument - this is a dynamically generated string, so that's OK.
993
994 Arguments:
995 field number of field to be extracted,
996 first field = 1, whole string = 0, last field = -1
997 separators characters that are used to break string into tokens
998 s points to the string from which to extract the subfield
999
1000 Returns: NULL if the field was not found,
1001 a pointer to the field's data inside s (modified to add 0)
1002 */
1003
1004 static uschar *
1005 expand_gettokened (int field, uschar *separators, uschar *s)
1006 {
1007 int sep = 1;
1008 int count;
1009 uschar *ss = s;
1010 uschar *fieldtext = NULL;
1011
1012 if (field == 0) return s;
1013
1014 /* Break the line up into fields in place; for field > 0 we stop when we have
1015 done the number of fields we want. For field < 0 we continue till the end of
1016 the string, counting the number of fields. */
1017
1018 count = (field > 0)? field : INT_MAX;
1019
1020 while (count-- > 0)
1021 {
1022 size_t len;
1023
1024 /* Previous field was the last one in the string. For a positive field
1025 number, this means there are not enough fields. For a negative field number,
1026 check that there are enough, and scan back to find the one that is wanted. */
1027
1028 if (sep == 0)
1029 {
1030 if (field > 0 || (-field) > (INT_MAX - count - 1)) return NULL;
1031 if ((-field) == (INT_MAX - count - 1)) return s;
1032 while (field++ < 0)
1033 {
1034 ss--;
1035 while (ss[-1] != 0) ss--;
1036 }
1037 fieldtext = ss;
1038 break;
1039 }
1040
1041 /* Previous field was not last in the string; save its start and put a
1042 zero at its end. */
1043
1044 fieldtext = ss;
1045 len = Ustrcspn(ss, separators);
1046 sep = ss[len];
1047 ss[len] = 0;
1048 ss += len + 1;
1049 }
1050
1051 return fieldtext;
1052 }
1053
1054
1055
1056 /*************************************************
1057 * Extract a substring from a string *
1058 *************************************************/
1059
1060 /* Perform the ${substr or ${length expansion operations.
1061
1062 Arguments:
1063 subject the input string
1064 value1 the offset from the start of the input string to the start of
1065 the output string; if negative, count from the right.
1066 value2 the length of the output string, or negative (-1) for unset
1067 if value1 is positive, unset means "all after"
1068 if value1 is negative, unset means "all before"
1069 len set to the length of the returned string
1070
1071 Returns: pointer to the output string, or NULL if there is an error
1072 */
1073
1074 static uschar *
1075 extract_substr(uschar *subject, int value1, int value2, int *len)
1076 {
1077 int sublen = Ustrlen(subject);
1078
1079 if (value1 < 0) /* count from right */
1080 {
1081 value1 += sublen;
1082
1083 /* If the position is before the start, skip to the start, and adjust the
1084 length. If the length ends up negative, the substring is null because nothing
1085 can precede. This falls out naturally when the length is unset, meaning "all
1086 to the left". */
1087
1088 if (value1 < 0)
1089 {
1090 value2 += value1;
1091 if (value2 < 0) value2 = 0;
1092 value1 = 0;
1093 }
1094
1095 /* Otherwise an unset length => characters before value1 */
1096
1097 else if (value2 < 0)
1098 {
1099 value2 = value1;
1100 value1 = 0;
1101 }
1102 }
1103
1104 /* For a non-negative offset, if the starting position is past the end of the
1105 string, the result will be the null string. Otherwise, an unset length means
1106 "rest"; just set it to the maximum - it will be cut down below if necessary. */
1107
1108 else
1109 {
1110 if (value1 > sublen)
1111 {
1112 value1 = sublen;
1113 value2 = 0;
1114 }
1115 else if (value2 < 0) value2 = sublen;
1116 }
1117
1118 /* Cut the length down to the maximum possible for the offset value, and get
1119 the required characters. */
1120
1121 if (value1 + value2 > sublen) value2 = sublen - value1;
1122 *len = value2;
1123 return subject + value1;
1124 }
1125
1126
1127
1128
1129 /*************************************************
1130 * Old-style hash of a string *
1131 *************************************************/
1132
1133 /* Perform the ${hash expansion operation.
1134
1135 Arguments:
1136 subject the input string (an expanded substring)
1137 value1 the length of the output string; if greater or equal to the
1138 length of the input string, the input string is returned
1139 value2 the number of hash characters to use, or 26 if negative
1140 len set to the length of the returned string
1141
1142 Returns: pointer to the output string, or NULL if there is an error
1143 */
1144
1145 static uschar *
1146 compute_hash(uschar *subject, int value1, int value2, int *len)
1147 {
1148 int sublen = Ustrlen(subject);
1149
1150 if (value2 < 0) value2 = 26;
1151 else if (value2 > Ustrlen(hashcodes))
1152 {
1153 expand_string_message =
1154 string_sprintf("hash count \"%d\" too big", value2);
1155 return NULL;
1156 }
1157
1158 /* Calculate the hash text. We know it is shorter than the original string, so
1159 can safely place it in subject[] (we know that subject is always itself an
1160 expanded substring). */
1161
1162 if (value1 < sublen)
1163 {
1164 int c;
1165 int i = 0;
1166 int j = value1;
1167 while ((c = (subject[j])) != 0)
1168 {
1169 int shift = (c + j++) & 7;
1170 subject[i] ^= (c << shift) | (c >> (8-shift));
1171 if (++i >= value1) i = 0;
1172 }
1173 for (i = 0; i < value1; i++)
1174 subject[i] = hashcodes[(subject[i]) % value2];
1175 }
1176 else value1 = sublen;
1177
1178 *len = value1;
1179 return subject;
1180 }
1181
1182
1183
1184
1185 /*************************************************
1186 * Numeric hash of a string *
1187 *************************************************/
1188
1189 /* Perform the ${nhash expansion operation. The first characters of the
1190 string are treated as most important, and get the highest prime numbers.
1191
1192 Arguments:
1193 subject the input string
1194 value1 the maximum value of the first part of the result
1195 value2 the maximum value of the second part of the result,
1196 or negative to produce only a one-part result
1197 len set to the length of the returned string
1198
1199 Returns: pointer to the output string, or NULL if there is an error.
1200 */
1201
1202 static uschar *
1203 compute_nhash (uschar *subject, int value1, int value2, int *len)
1204 {
1205 uschar *s = subject;
1206 int i = 0;
1207 unsigned long int total = 0; /* no overflow */
1208
1209 while (*s != 0)
1210 {
1211 if (i == 0) i = sizeof(prime)/sizeof(int) - 1;
1212 total += prime[i--] * (unsigned int)(*s++);
1213 }
1214
1215 /* If value2 is unset, just compute one number */
1216
1217 if (value2 < 0)
1218 {
1219 s = string_sprintf("%d", total % value1);
1220 }
1221
1222 /* Otherwise do a div/mod hash */
1223
1224 else
1225 {
1226 total = total % (value1 * value2);
1227 s = string_sprintf("%d/%d", total/value2, total % value2);
1228 }
1229
1230 *len = Ustrlen(s);
1231 return s;
1232 }
1233
1234
1235
1236
1237
1238 /*************************************************
1239 * Find the value of a header or headers *
1240 *************************************************/
1241
1242 /* Multiple instances of the same header get concatenated, and this function
1243 can also return a concatenation of all the header lines. When concatenating
1244 specific headers that contain lists of addresses, a comma is inserted between
1245 them. Otherwise we use a straight concatenation. Because some messages can have
1246 pathologically large number of lines, there is a limit on the length that is
1247 returned. Also, to avoid massive store use which would result from using
1248 string_cat() as it copies and extends strings, we do a preliminary pass to find
1249 out exactly how much store will be needed. On "normal" messages this will be
1250 pretty trivial.
1251
1252 Arguments:
1253 name the name of the header, without the leading $header_ or $h_,
1254 or NULL if a concatenation of all headers is required
1255 exists_only TRUE if called from a def: test; don't need to build a string;
1256 just return a string that is not "" and not "0" if the header
1257 exists
1258 newsize return the size of memory block that was obtained; may be NULL
1259 if exists_only is TRUE
1260 want_raw TRUE if called for $rh_ or $rheader_ variables; no processing,
1261 other than concatenating, will be done on the header. Also used
1262 for $message_headers_raw.
1263 charset name of charset to translate MIME words to; used only if
1264 want_raw is false; if NULL, no translation is done (this is
1265 used for $bh_ and $bheader_)
1266
1267 Returns: NULL if the header does not exist, else a pointer to a new
1268 store block
1269 */
1270
1271 static uschar *
1272 find_header(uschar *name, BOOL exists_only, int *newsize, BOOL want_raw,
1273 uschar *charset)
1274 {
1275 BOOL found = name == NULL;
1276 int comma = 0;
1277 int len = found? 0 : Ustrlen(name);
1278 int i;
1279 uschar *yield = NULL;
1280 uschar *ptr = NULL;
1281
1282 /* Loop for two passes - saves code repetition */
1283
1284 for (i = 0; i < 2; i++)
1285 {
1286 int size = 0;
1287 header_line *h;
1288
1289 for (h = header_list; size < header_insert_maxlen && h != NULL; h = h->next)
1290 {
1291 if (h->type != htype_old && h->text != NULL) /* NULL => Received: placeholder */
1292 {
1293 if (name == NULL || (len <= h->slen && strncmpic(name, h->text, len) == 0))
1294 {
1295 int ilen;
1296 uschar *t;
1297
1298 if (exists_only) return US"1"; /* don't need actual string */
1299 found = TRUE;
1300 t = h->text + len; /* text to insert */
1301 if (!want_raw) /* unless wanted raw, */
1302 while (isspace(*t)) t++; /* remove leading white space */
1303 ilen = h->slen - (t - h->text); /* length to insert */
1304
1305 /* Unless wanted raw, remove trailing whitespace, including the
1306 newline. */
1307
1308 if (!want_raw)
1309 while (ilen > 0 && isspace(t[ilen-1])) ilen--;
1310
1311 /* Set comma = 1 if handling a single header and it's one of those
1312 that contains an address list, except when asked for raw headers. Only
1313 need to do this once. */
1314
1315 if (!want_raw && name != NULL && comma == 0 &&
1316 Ustrchr("BCFRST", h->type) != NULL)
1317 comma = 1;
1318
1319 /* First pass - compute total store needed; second pass - compute
1320 total store used, including this header. */
1321
1322 size += ilen + comma + 1; /* +1 for the newline */
1323
1324 /* Second pass - concatentate the data, up to a maximum. Note that
1325 the loop stops when size hits the limit. */
1326
1327 if (i != 0)
1328 {
1329 if (size > header_insert_maxlen)
1330 {
1331 ilen -= size - header_insert_maxlen - 1;
1332 comma = 0;
1333 }
1334 Ustrncpy(ptr, t, ilen);
1335 ptr += ilen;
1336
1337 /* For a non-raw header, put in the comma if needed, then add
1338 back the newline we removed above, provided there was some text in
1339 the header. */
1340
1341 if (!want_raw && ilen > 0)
1342 {
1343 if (comma != 0) *ptr++ = ',';
1344 *ptr++ = '\n';
1345 }
1346 }
1347 }
1348 }
1349 }
1350
1351 /* At end of first pass, return NULL if no header found. Then truncate size
1352 if necessary, and get the buffer to hold the data, returning the buffer size.
1353 */
1354
1355 if (i == 0)
1356 {
1357 if (!found) return NULL;
1358 if (size > header_insert_maxlen) size = header_insert_maxlen;
1359 *newsize = size + 1;
1360 ptr = yield = store_get(*newsize);
1361 }
1362 }
1363
1364 /* That's all we do for raw header expansion. */
1365
1366 if (want_raw)
1367 {
1368 *ptr = 0;
1369 }
1370
1371 /* Otherwise, remove a final newline and a redundant added comma. Then we do
1372 RFC 2047 decoding, translating the charset if requested. The rfc2047_decode2()
1373 function can return an error with decoded data if the charset translation
1374 fails. If decoding fails, it returns NULL. */
1375
1376 else
1377 {
1378 uschar *decoded, *error;
1379 if (ptr > yield && ptr[-1] == '\n') ptr--;
1380 if (ptr > yield && comma != 0 && ptr[-1] == ',') ptr--;
1381 *ptr = 0;
1382 decoded = rfc2047_decode2(yield, check_rfc2047_length, charset, '?', NULL,
1383 newsize, &error);
1384 if (error != NULL)
1385 {
1386 DEBUG(D_any) debug_printf("*** error in RFC 2047 decoding: %s\n"
1387 " input was: %s\n", error, yield);
1388 }
1389 if (decoded != NULL) yield = decoded;
1390 }
1391
1392 return yield;
1393 }
1394
1395
1396
1397
1398 /*************************************************
1399 * Find value of a variable *
1400 *************************************************/
1401
1402 /* The table of variables is kept in alphabetic order, so we can search it
1403 using a binary chop. The "choplen" variable is nothing to do with the binary
1404 chop.
1405
1406 Arguments:
1407 name the name of the variable being sought
1408 exists_only TRUE if this is a def: test; passed on to find_header()
1409 skipping TRUE => skip any processing evaluation; this is not the same as
1410 exists_only because def: may test for values that are first
1411 evaluated here
1412 newsize pointer to an int which is initially zero; if the answer is in
1413 a new memory buffer, *newsize is set to its size
1414
1415 Returns: NULL if the variable does not exist, or
1416 a pointer to the variable's contents, or
1417 something non-NULL if exists_only is TRUE
1418 */
1419
1420 static uschar *
1421 find_variable(uschar *name, BOOL exists_only, BOOL skipping, int *newsize)
1422 {
1423 int first = 0;
1424 int last = var_table_size;
1425
1426 /* Handle ACL variables, whose names are of the form acl_cxxx or acl_mxxx.
1427 Originally, xxx had to be a number in the range 0-9 (later 0-19), but from
1428 release 4.64 onwards arbitrary names are permitted, as long as the first 5
1429 characters are acl_c or acl_m and the sixth is either a digit or an underscore
1430 (this gave backwards compatibility at the changeover). There may be built-in
1431 variables whose names start acl_ but they should never start in this way. This
1432 slightly messy specification is a consequence of the history, needless to say.
1433
1434 If an ACL variable does not exist, treat it as empty, unless strict_acl_vars is
1435 set, in which case give an error. */
1436
1437 if ((Ustrncmp(name, "acl_c", 5) == 0 || Ustrncmp(name, "acl_m", 5) == 0) &&
1438 !isalpha(name[5]))
1439 {
1440 tree_node *node =
1441 tree_search((name[4] == 'c')? acl_var_c : acl_var_m, name + 4);
1442 return (node == NULL)? (strict_acl_vars? NULL : US"") : node->data.ptr;
1443 }
1444
1445 /* Handle $auth<n> variables. */
1446
1447 if (Ustrncmp(name, "auth", 4) == 0)
1448 {
1449 uschar *endptr;
1450 int n = Ustrtoul(name + 4, &endptr, 10);
1451 if (*endptr == 0 && n != 0 && n <= AUTH_VARS)
1452 return (auth_vars[n-1] == NULL)? US"" : auth_vars[n-1];
1453 }
1454
1455 /* For all other variables, search the table */
1456
1457 while (last > first)
1458 {
1459 uschar *s, *domain;
1460 uschar **ss;
1461 int middle = (first + last)/2;
1462 int c = Ustrcmp(name, var_table[middle].name);
1463
1464 if (c > 0) { first = middle + 1; continue; }
1465 if (c < 0) { last = middle; continue; }
1466
1467 /* Found an existing variable. If in skipping state, the value isn't needed,
1468 and we want to avoid processing (such as looking up the host name). */
1469
1470 if (skipping) return US"";
1471
1472 switch (var_table[middle].type)
1473 {
1474 case vtype_filter_int:
1475 if (!filter_running) return NULL;
1476 /* Fall through */
1477 /* VVVVVVVVVVVV */
1478 case vtype_int:
1479 sprintf(CS var_buffer, "%d", *(int *)(var_table[middle].value)); /* Integer */
1480 return var_buffer;
1481
1482 case vtype_ino:
1483 sprintf(CS var_buffer, "%ld", (long int)(*(ino_t *)(var_table[middle].value))); /* Inode */
1484 return var_buffer;
1485
1486 case vtype_gid:
1487 sprintf(CS var_buffer, "%ld", (long int)(*(gid_t *)(var_table[middle].value))); /* gid */
1488 return var_buffer;
1489
1490 case vtype_uid:
1491 sprintf(CS var_buffer, "%ld", (long int)(*(uid_t *)(var_table[middle].value))); /* uid */
1492 return var_buffer;
1493
1494 case vtype_stringptr: /* Pointer to string */
1495 s = *((uschar **)(var_table[middle].value));
1496 return (s == NULL)? US"" : s;
1497
1498 case vtype_pid:
1499 sprintf(CS var_buffer, "%d", (int)getpid()); /* pid */
1500 return var_buffer;
1501
1502 case vtype_load_avg:
1503 sprintf(CS var_buffer, "%d", OS_GETLOADAVG()); /* load_average */
1504 return var_buffer;
1505
1506 case vtype_host_lookup: /* Lookup if not done so */
1507 if (sender_host_name == NULL && sender_host_address != NULL &&
1508 !host_lookup_failed && host_name_lookup() == OK)
1509 host_build_sender_fullhost();
1510 return (sender_host_name == NULL)? US"" : sender_host_name;
1511
1512 case vtype_localpart: /* Get local part from address */
1513 s = *((uschar **)(var_table[middle].value));
1514 if (s == NULL) return US"";
1515 domain = Ustrrchr(s, '@');
1516 if (domain == NULL) return s;
1517 if (domain - s > sizeof(var_buffer) - 1)
1518 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "local part longer than %d in "
1519 "string expansion", sizeof(var_buffer));
1520 Ustrncpy(var_buffer, s, domain - s);
1521 var_buffer[domain - s] = 0;
1522 return var_buffer;
1523
1524 case vtype_domain: /* Get domain from address */
1525 s = *((uschar **)(var_table[middle].value));
1526 if (s == NULL) return US"";
1527 domain = Ustrrchr(s, '@');
1528 return (domain == NULL)? US"" : domain + 1;
1529
1530 case vtype_msgheaders:
1531 return find_header(NULL, exists_only, newsize, FALSE, NULL);
1532
1533 case vtype_msgheaders_raw:
1534 return find_header(NULL, exists_only, newsize, TRUE, NULL);
1535
1536 case vtype_msgbody: /* Pointer to msgbody string */
1537 case vtype_msgbody_end: /* Ditto, the end of the msg */
1538 ss = (uschar **)(var_table[middle].value);
1539 if (*ss == NULL && deliver_datafile >= 0) /* Read body when needed */
1540 {
1541 uschar *body;
1542 off_t start_offset = SPOOL_DATA_START_OFFSET;
1543 int len = message_body_visible;
1544 if (len > message_size) len = message_size;
1545 *ss = body = store_malloc(len+1);
1546 body[0] = 0;
1547 if (var_table[middle].type == vtype_msgbody_end)
1548 {
1549 struct stat statbuf;
1550 if (fstat(deliver_datafile, &statbuf) == 0)
1551 {
1552 start_offset = statbuf.st_size - len;
1553 if (start_offset < SPOOL_DATA_START_OFFSET)
1554 start_offset = SPOOL_DATA_START_OFFSET;
1555 }
1556 }
1557 lseek(deliver_datafile, start_offset, SEEK_SET);
1558 len = read(deliver_datafile, body, len);
1559 if (len > 0)
1560 {
1561 body[len] = 0;
1562 if (message_body_newlines) /* Separate loops for efficiency */
1563 {
1564 while (len > 0)
1565 { if (body[--len] == 0) body[len] = ' '; }
1566 }
1567 else
1568 {
1569 while (len > 0)
1570 { if (body[--len] == '\n' || body[len] == 0) body[len] = ' '; }
1571 }
1572 }
1573 }
1574 return (*ss == NULL)? US"" : *ss;
1575
1576 case vtype_todbsdin: /* BSD inbox time of day */
1577 return tod_stamp(tod_bsdin);
1578
1579 case vtype_tode: /* Unix epoch time of day */
1580 return tod_stamp(tod_epoch);
1581
1582 case vtype_todf: /* Full time of day */
1583 return tod_stamp(tod_full);
1584
1585 case vtype_todl: /* Log format time of day */
1586 return tod_stamp(tod_log_bare); /* (without timezone) */
1587
1588 case vtype_todzone: /* Time zone offset only */
1589 return tod_stamp(tod_zone);
1590
1591 case vtype_todzulu: /* Zulu time */
1592 return tod_stamp(tod_zulu);
1593
1594 case vtype_todlf: /* Log file datestamp tod */
1595 return tod_stamp(tod_log_datestamp_daily);
1596
1597 case vtype_reply: /* Get reply address */
1598 s = find_header(US"reply-to:", exists_only, newsize, TRUE,
1599 headers_charset);
1600 if (s != NULL) while (isspace(*s)) s++;
1601 if (s == NULL || *s == 0)
1602 {
1603 *newsize = 0; /* For the *s==0 case */
1604 s = find_header(US"from:", exists_only, newsize, TRUE, headers_charset);
1605 }
1606 if (s != NULL)
1607 {
1608 uschar *t;
1609 while (isspace(*s)) s++;
1610 for (t = s; *t != 0; t++) if (*t == '\n') *t = ' ';
1611 while (t > s && isspace(t[-1])) t--;
1612 *t = 0;
1613 }
1614 return (s == NULL)? US"" : s;
1615
1616 /* A recipients list is available only during system message filtering,
1617 during ACL processing after DATA, and while expanding pipe commands
1618 generated from a system filter, but not elsewhere. */
1619
1620 case vtype_recipients:
1621 if (!enable_dollar_recipients) return NULL; else
1622 {
1623 int size = 128;
1624 int ptr = 0;
1625 int i;
1626 s = store_get(size);
1627 for (i = 0; i < recipients_count; i++)
1628 {
1629 if (i != 0) s = string_cat(s, &size, &ptr, US", ", 2);
1630 s = string_cat(s, &size, &ptr, recipients_list[i].address,
1631 Ustrlen(recipients_list[i].address));
1632 }
1633 s[ptr] = 0; /* string_cat() leaves room */
1634 }
1635 return s;
1636
1637 case vtype_pspace:
1638 {
1639 int inodes;
1640 sprintf(CS var_buffer, "%d",
1641 receive_statvfs(var_table[middle].value == (void *)TRUE, &inodes));
1642 }
1643 return var_buffer;
1644
1645 case vtype_pinodes:
1646 {
1647 int inodes;
1648 (void) receive_statvfs(var_table[middle].value == (void *)TRUE, &inodes);
1649 sprintf(CS var_buffer, "%d", inodes);
1650 }
1651 return var_buffer;
1652
1653 #ifndef DISABLE_DKIM
1654 case vtype_dkim:
1655 return dkim_exim_expand_query((int)(long)var_table[middle].value);
1656 #endif
1657
1658 }
1659 }
1660
1661 return NULL; /* Unknown variable name */
1662 }
1663
1664
1665
1666
1667 /*************************************************
1668 * Read and expand substrings *
1669 *************************************************/
1670
1671 /* This function is called to read and expand argument substrings for various
1672 expansion items. Some have a minimum requirement that is less than the maximum;
1673 in these cases, the first non-present one is set to NULL.
1674
1675 Arguments:
1676 sub points to vector of pointers to set
1677 n maximum number of substrings
1678 m minimum required
1679 sptr points to current string pointer
1680 skipping the skipping flag
1681 check_end if TRUE, check for final '}'
1682 name name of item, for error message
1683
1684 Returns: 0 OK; string pointer updated
1685 1 curly bracketing error (too few arguments)
1686 2 too many arguments (only if check_end is set); message set
1687 3 other error (expansion failure)
1688 */
1689
1690 static int
1691 read_subs(uschar **sub, int n, int m, uschar **sptr, BOOL skipping,
1692 BOOL check_end, uschar *name)
1693 {
1694 int i;
1695 uschar *s = *sptr;
1696
1697 while (isspace(*s)) s++;
1698 for (i = 0; i < n; i++)
1699 {
1700 if (*s != '{')
1701 {
1702 if (i < m) return 1;
1703 sub[i] = NULL;
1704 break;
1705 }
1706 sub[i] = expand_string_internal(s+1, TRUE, &s, skipping, TRUE);
1707 if (sub[i] == NULL) return 3;
1708 if (*s++ != '}') return 1;
1709 while (isspace(*s)) s++;
1710 }
1711 if (check_end && *s++ != '}')
1712 {
1713 if (s[-1] == '{')
1714 {
1715 expand_string_message = string_sprintf("Too many arguments for \"%s\" "
1716 "(max is %d)", name, n);
1717 return 2;
1718 }
1719 return 1;
1720 }
1721
1722 *sptr = s;
1723 return 0;
1724 }
1725
1726
1727
1728
1729 /*************************************************
1730 * Elaborate message for bad variable *
1731 *************************************************/
1732
1733 /* For the "unknown variable" message, take a look at the variable's name, and
1734 give additional information about possible ACL variables. The extra information
1735 is added on to expand_string_message.
1736
1737 Argument: the name of the variable
1738 Returns: nothing
1739 */
1740
1741 static void
1742 check_variable_error_message(uschar *name)
1743 {
1744 if (Ustrncmp(name, "acl_", 4) == 0)
1745 expand_string_message = string_sprintf("%s (%s)", expand_string_message,
1746 (name[4] == 'c' || name[4] == 'm')?
1747 (isalpha(name[5])?
1748 US"6th character of a user-defined ACL variable must be a digit or underscore" :
1749 US"strict_acl_vars is set" /* Syntax is OK, it has to be this */
1750 ) :
1751 US"user-defined ACL variables must start acl_c or acl_m");
1752 }
1753
1754
1755
1756 /*************************************************
1757 * Read and evaluate a condition *
1758 *************************************************/
1759
1760 /*
1761 Arguments:
1762 s points to the start of the condition text
1763 yield points to a BOOL to hold the result of the condition test;
1764 if NULL, we are just reading through a condition that is
1765 part of an "or" combination to check syntax, or in a state
1766 where the answer isn't required
1767
1768 Returns: a pointer to the first character after the condition, or
1769 NULL after an error
1770 */
1771
1772 static uschar *
1773 eval_condition(uschar *s, BOOL *yield)
1774 {
1775 BOOL testfor = TRUE;
1776 BOOL tempcond, combined_cond;
1777 BOOL *subcondptr;
1778 BOOL sub2_honour_dollar = TRUE;
1779 int i, rc, cond_type, roffset;
1780 int num[2];
1781 struct stat statbuf;
1782 uschar name[256];
1783 uschar *sub[4];
1784
1785 const pcre *re;
1786 const uschar *rerror;
1787
1788 for (;;)
1789 {
1790 while (isspace(*s)) s++;
1791 if (*s == '!') { testfor = !testfor; s++; } else break;
1792 }
1793
1794 /* Numeric comparisons are symbolic */
1795
1796 if (*s == '=' || *s == '>' || *s == '<')
1797 {
1798 int p = 0;
1799 name[p++] = *s++;
1800 if (*s == '=')
1801 {
1802 name[p++] = '=';
1803 s++;
1804 }
1805 name[p] = 0;
1806 }
1807
1808 /* All other conditions are named */
1809
1810 else s = read_name(name, 256, s, US"_");
1811
1812 /* If we haven't read a name, it means some non-alpha character is first. */
1813
1814 if (name[0] == 0)
1815 {
1816 expand_string_message = string_sprintf("condition name expected, "
1817 "but found \"%.16s\"", s);
1818 return NULL;
1819 }
1820
1821 /* Find which condition we are dealing with, and switch on it */
1822
1823 cond_type = chop_match(name, cond_table, sizeof(cond_table)/sizeof(uschar *));
1824 switch(cond_type)
1825 {
1826 /* def: tests for a non-empty variable, or for the existence of a header. If
1827 yield == NULL we are in a skipping state, and don't care about the answer. */
1828
1829 case ECOND_DEF:
1830 if (*s != ':')
1831 {
1832 expand_string_message = US"\":\" expected after \"def\"";
1833 return NULL;
1834 }
1835
1836 s = read_name(name, 256, s+1, US"_");
1837
1838 /* Test for a header's existence. If the name contains a closing brace
1839 character, this may be a user error where the terminating colon has been
1840 omitted. Set a flag to adjust a subsequent error message in this case. */
1841
1842 if (Ustrncmp(name, "h_", 2) == 0 ||
1843 Ustrncmp(name, "rh_", 3) == 0 ||
1844 Ustrncmp(name, "bh_", 3) == 0 ||
1845 Ustrncmp(name, "header_", 7) == 0 ||
1846 Ustrncmp(name, "rheader_", 8) == 0 ||
1847 Ustrncmp(name, "bheader_", 8) == 0)
1848 {
1849 s = read_header_name(name, 256, s);
1850 if (Ustrchr(name, '}') != NULL) malformed_header = TRUE;
1851 if (yield != NULL) *yield =
1852 (find_header(name, TRUE, NULL, FALSE, NULL) != NULL) == testfor;
1853 }
1854
1855 /* Test for a variable's having a non-empty value. A non-existent variable
1856 causes an expansion failure. */
1857
1858 else
1859 {
1860 uschar *value = find_variable(name, TRUE, yield == NULL, NULL);
1861 if (value == NULL)
1862 {
1863 expand_string_message = (name[0] == 0)?
1864 string_sprintf("variable name omitted after \"def:\"") :
1865 string_sprintf("unknown variable \"%s\" after \"def:\"", name);
1866 check_variable_error_message(name);
1867 return NULL;
1868 }
1869 if (yield != NULL) *yield = (value[0] != 0) == testfor;
1870 }
1871
1872 return s;
1873
1874
1875 /* first_delivery tests for first delivery attempt */
1876
1877 case ECOND_FIRST_DELIVERY:
1878 if (yield != NULL) *yield = deliver_firsttime == testfor;
1879 return s;
1880
1881
1882 /* queue_running tests for any process started by a queue runner */
1883
1884 case ECOND_QUEUE_RUNNING:
1885 if (yield != NULL) *yield = (queue_run_pid != (pid_t)0) == testfor;
1886 return s;
1887
1888
1889 /* exists: tests for file existence
1890 isip: tests for any IP address
1891 isip4: tests for an IPv4 address
1892 isip6: tests for an IPv6 address
1893 pam: does PAM authentication
1894 radius: does RADIUS authentication
1895 ldapauth: does LDAP authentication
1896 pwcheck: does Cyrus SASL pwcheck authentication
1897 */
1898
1899 case ECOND_EXISTS:
1900 case ECOND_ISIP:
1901 case ECOND_ISIP4:
1902 case ECOND_ISIP6:
1903 case ECOND_PAM:
1904 case ECOND_RADIUS:
1905 case ECOND_LDAPAUTH:
1906 case ECOND_PWCHECK:
1907
1908 while (isspace(*s)) s++;
1909 if (*s != '{') goto COND_FAILED_CURLY_START;
1910
1911 sub[0] = expand_string_internal(s+1, TRUE, &s, yield == NULL, TRUE);
1912 if (sub[0] == NULL) return NULL;
1913 if (*s++ != '}') goto COND_FAILED_CURLY_END;
1914
1915 if (yield == NULL) return s; /* No need to run the test if skipping */
1916
1917 switch(cond_type)
1918 {
1919 case ECOND_EXISTS:
1920 if ((expand_forbid & RDO_EXISTS) != 0)
1921 {
1922 expand_string_message = US"File existence tests are not permitted";
1923 return NULL;
1924 }
1925 *yield = (Ustat(sub[0], &statbuf) == 0) == testfor;
1926 break;
1927
1928 case ECOND_ISIP:
1929 case ECOND_ISIP4:
1930 case ECOND_ISIP6:
1931 rc = string_is_ip_address(sub[0], NULL);
1932 *yield = ((cond_type == ECOND_ISIP)? (rc != 0) :
1933 (cond_type == ECOND_ISIP4)? (rc == 4) : (rc == 6)) == testfor;
1934 break;
1935
1936 /* Various authentication tests - all optionally compiled */
1937
1938 case ECOND_PAM:
1939 #ifdef SUPPORT_PAM
1940 rc = auth_call_pam(sub[0], &expand_string_message);
1941 goto END_AUTH;
1942 #else
1943 goto COND_FAILED_NOT_COMPILED;
1944 #endif /* SUPPORT_PAM */
1945
1946 case ECOND_RADIUS:
1947 #ifdef RADIUS_CONFIG_FILE
1948 rc = auth_call_radius(sub[0], &expand_string_message);
1949 goto END_AUTH;
1950 #else
1951 goto COND_FAILED_NOT_COMPILED;
1952 #endif /* RADIUS_CONFIG_FILE */
1953
1954 case ECOND_LDAPAUTH:
1955 #ifdef LOOKUP_LDAP
1956 {
1957 /* Just to keep the interface the same */
1958 BOOL do_cache;
1959 int old_pool = store_pool;
1960 store_pool = POOL_SEARCH;
1961 rc = eldapauth_find((void *)(-1), NULL, sub[0], Ustrlen(sub[0]), NULL,
1962 &expand_string_message, &do_cache);
1963 store_pool = old_pool;
1964 }
1965 goto END_AUTH;
1966 #else
1967 goto COND_FAILED_NOT_COMPILED;
1968 #endif /* LOOKUP_LDAP */
1969
1970 case ECOND_PWCHECK:
1971 #ifdef CYRUS_PWCHECK_SOCKET
1972 rc = auth_call_pwcheck(sub[0], &expand_string_message);
1973 goto END_AUTH;
1974 #else
1975 goto COND_FAILED_NOT_COMPILED;
1976 #endif /* CYRUS_PWCHECK_SOCKET */
1977
1978 #if defined(SUPPORT_PAM) || defined(RADIUS_CONFIG_FILE) || \
1979 defined(LOOKUP_LDAP) || defined(CYRUS_PWCHECK_SOCKET)
1980 END_AUTH:
1981 if (rc == ERROR || rc == DEFER) return NULL;
1982 *yield = (rc == OK) == testfor;
1983 #endif
1984 }
1985 return s;
1986
1987
1988 /* saslauthd: does Cyrus saslauthd authentication. Four parameters are used:
1989
1990 ${if saslauthd {{username}{password}{service}{realm}} {yes}[no}}
1991
1992 However, the last two are optional. That is why the whole set is enclosed
1993 in their own set or braces. */
1994
1995 case ECOND_SASLAUTHD:
1996 #ifndef CYRUS_SASLAUTHD_SOCKET
1997 goto COND_FAILED_NOT_COMPILED;
1998 #else
1999 while (isspace(*s)) s++;
2000 if (*s++ != '{') goto COND_FAILED_CURLY_START;
2001 switch(read_subs(sub, 4, 2, &s, yield == NULL, TRUE, US"saslauthd"))
2002 {
2003 case 1: expand_string_message = US"too few arguments or bracketing "
2004 "error for saslauthd";
2005 case 2:
2006 case 3: return NULL;
2007 }
2008 if (sub[2] == NULL) sub[3] = NULL; /* realm if no service */
2009 if (yield != NULL)
2010 {
2011 int rc;
2012 rc = auth_call_saslauthd(sub[0], sub[1], sub[2], sub[3],
2013 &expand_string_message);
2014 if (rc == ERROR || rc == DEFER) return NULL;
2015 *yield = (rc == OK) == testfor;
2016 }
2017 return s;
2018 #endif /* CYRUS_SASLAUTHD_SOCKET */
2019
2020
2021 /* symbolic operators for numeric and string comparison, and a number of
2022 other operators, all requiring two arguments.
2023
2024 crypteq: encrypts plaintext and compares against an encrypted text,
2025 using crypt(), crypt16(), MD5 or SHA-1
2026 inlist/inlisti: checks if first argument is in the list of the second
2027 match: does a regular expression match and sets up the numerical
2028 variables if it succeeds
2029 match_address: matches in an address list
2030 match_domain: matches in a domain list
2031 match_ip: matches a host list that is restricted to IP addresses
2032 match_local_part: matches in a local part list
2033 */
2034
2035 case ECOND_MATCH_ADDRESS:
2036 case ECOND_MATCH_DOMAIN:
2037 case ECOND_MATCH_IP:
2038 case ECOND_MATCH_LOCAL_PART:
2039 #ifndef EXPAND_LISTMATCH_RHS
2040 sub2_honour_dollar = FALSE;
2041 #endif
2042 /* FALLTHROUGH */
2043
2044 case ECOND_CRYPTEQ:
2045 case ECOND_INLIST:
2046 case ECOND_INLISTI:
2047 case ECOND_MATCH:
2048
2049 case ECOND_NUM_L: /* Numerical comparisons */
2050 case ECOND_NUM_LE:
2051 case ECOND_NUM_E:
2052 case ECOND_NUM_EE:
2053 case ECOND_NUM_G:
2054 case ECOND_NUM_GE:
2055
2056 case ECOND_STR_LT: /* String comparisons */
2057 case ECOND_STR_LTI:
2058 case ECOND_STR_LE:
2059 case ECOND_STR_LEI:
2060 case ECOND_STR_EQ:
2061 case ECOND_STR_EQI:
2062 case ECOND_STR_GT:
2063 case ECOND_STR_GTI:
2064 case ECOND_STR_GE:
2065 case ECOND_STR_GEI:
2066
2067 for (i = 0; i < 2; i++)
2068 {
2069 /* Sometimes, we don't expand substrings; too many insecure configurations
2070 created using match_address{}{} and friends, where the second param
2071 includes information from untrustworthy sources. */
2072 BOOL honour_dollar = TRUE;
2073 if ((i > 0) && !sub2_honour_dollar)
2074 honour_dollar = FALSE;
2075
2076 while (isspace(*s)) s++;
2077 if (*s != '{')
2078 {
2079 if (i == 0) goto COND_FAILED_CURLY_START;
2080 expand_string_message = string_sprintf("missing 2nd string in {} "
2081 "after \"%s\"", name);
2082 return NULL;
2083 }
2084 sub[i] = expand_string_internal(s+1, TRUE, &s, yield == NULL,
2085 honour_dollar);
2086 if (sub[i] == NULL) return NULL;
2087 if (*s++ != '}') goto COND_FAILED_CURLY_END;
2088
2089 /* Convert to numerical if required; we know that the names of all the
2090 conditions that compare numbers do not start with a letter. This just saves
2091 checking for them individually. */
2092
2093 if (!isalpha(name[0]) && yield != NULL)
2094 {
2095 if (sub[i][0] == 0)
2096 {
2097 num[i] = 0;
2098 DEBUG(D_expand)
2099 debug_printf("empty string cast to zero for numerical comparison\n");
2100 }
2101 else
2102 {
2103 num[i] = expand_string_integer(sub[i], FALSE);
2104 if (expand_string_message != NULL) return NULL;
2105 }
2106 }
2107 }
2108
2109 /* Result not required */
2110
2111 if (yield == NULL) return s;
2112
2113 /* Do an appropriate comparison */
2114
2115 switch(cond_type)
2116 {
2117 case ECOND_NUM_E:
2118 case ECOND_NUM_EE:
2119 *yield = (num[0] == num[1]) == testfor;
2120 break;
2121
2122 case ECOND_NUM_G:
2123 *yield = (num[0] > num[1]) == testfor;
2124 break;
2125
2126 case ECOND_NUM_GE:
2127 *yield = (num[0] >= num[1]) == testfor;
2128 break;
2129
2130 case ECOND_NUM_L:
2131 *yield = (num[0] < num[1]) == testfor;
2132 break;
2133
2134 case ECOND_NUM_LE:
2135 *yield = (num[0] <= num[1]) == testfor;
2136 break;
2137
2138 case ECOND_STR_LT:
2139 *yield = (Ustrcmp(sub[0], sub[1]) < 0) == testfor;
2140 break;
2141
2142 case ECOND_STR_LTI:
2143 *yield = (strcmpic(sub[0], sub[1]) < 0) == testfor;
2144 break;
2145
2146 case ECOND_STR_LE:
2147 *yield = (Ustrcmp(sub[0], sub[1]) <= 0) == testfor;
2148 break;
2149
2150 case ECOND_STR_LEI:
2151 *yield = (strcmpic(sub[0], sub[1]) <= 0) == testfor;
2152 break;
2153
2154 case ECOND_STR_EQ:
2155 *yield = (Ustrcmp(sub[0], sub[1]) == 0) == testfor;
2156 break;
2157
2158 case ECOND_STR_EQI:
2159 *yield = (strcmpic(sub[0], sub[1]) == 0) == testfor;
2160 break;
2161
2162 case ECOND_STR_GT:
2163 *yield = (Ustrcmp(sub[0], sub[1]) > 0) == testfor;
2164 break;
2165
2166 case ECOND_STR_GTI:
2167 *yield = (strcmpic(sub[0], sub[1]) > 0) == testfor;
2168 break;
2169
2170 case ECOND_STR_GE:
2171 *yield = (Ustrcmp(sub[0], sub[1]) >= 0) == testfor;
2172 break;
2173
2174 case ECOND_STR_GEI:
2175 *yield = (strcmpic(sub[0], sub[1]) >= 0) == testfor;
2176 break;
2177
2178 case ECOND_MATCH: /* Regular expression match */
2179 re = pcre_compile(CS sub[1], PCRE_COPT, (const char **)&rerror, &roffset,
2180 NULL);
2181 if (re == NULL)
2182 {
2183 expand_string_message = string_sprintf("regular expression error in "
2184 "\"%s\": %s at offset %d", sub[1], rerror, roffset);
2185 return NULL;
2186 }
2187 *yield = regex_match_and_setup(re, sub[0], 0, -1) == testfor;
2188 break;
2189
2190 case ECOND_MATCH_ADDRESS: /* Match in an address list */
2191 rc = match_address_list(sub[0], TRUE, FALSE, &(sub[1]), NULL, -1, 0, NULL);
2192 goto MATCHED_SOMETHING;
2193
2194 case ECOND_MATCH_DOMAIN: /* Match in a domain list */
2195 rc = match_isinlist(sub[0], &(sub[1]), 0, &domainlist_anchor, NULL,
2196 MCL_DOMAIN + MCL_NOEXPAND, TRUE, NULL);
2197 goto MATCHED_SOMETHING;
2198
2199 case ECOND_MATCH_IP: /* Match IP address in a host list */
2200 if (sub[0][0] != 0 && string_is_ip_address(sub[0], NULL) == 0)
2201 {
2202 expand_string_message = string_sprintf("\"%s\" is not an IP address",
2203 sub[0]);
2204 return NULL;
2205 }
2206 else
2207 {
2208 unsigned int *nullcache = NULL;
2209 check_host_block cb;
2210
2211 cb.host_name = US"";
2212 cb.host_address = sub[0];
2213
2214 /* If the host address starts off ::ffff: it is an IPv6 address in
2215 IPv4-compatible mode. Find the IPv4 part for checking against IPv4
2216 addresses. */
2217
2218 cb.host_ipv4 = (Ustrncmp(cb.host_address, "::ffff:", 7) == 0)?
2219 cb.host_address + 7 : cb.host_address;
2220
2221 rc = match_check_list(
2222 &sub[1], /* the list */
2223 0, /* separator character */
2224 &hostlist_anchor, /* anchor pointer */
2225 &nullcache, /* cache pointer */
2226 check_host, /* function for testing */
2227 &cb, /* argument for function */
2228 MCL_HOST, /* type of check */
2229 sub[0], /* text for debugging */
2230 NULL); /* where to pass back data */
2231 }
2232 goto MATCHED_SOMETHING;
2233
2234 case ECOND_MATCH_LOCAL_PART:
2235 rc = match_isinlist(sub[0], &(sub[1]), 0, &localpartlist_anchor, NULL,
2236 MCL_LOCALPART + MCL_NOEXPAND, TRUE, NULL);
2237 /* Fall through */
2238 /* VVVVVVVVVVVV */
2239 MATCHED_SOMETHING:
2240 switch(rc)
2241 {
2242 case OK:
2243 *yield = testfor;
2244 break;
2245
2246 case FAIL:
2247 *yield = !testfor;
2248 break;
2249
2250 case DEFER:
2251 expand_string_message = string_sprintf("unable to complete match "
2252 "against \"%s\": %s", sub[1], search_error_message);
2253 return NULL;
2254 }
2255
2256 break;
2257
2258 /* Various "encrypted" comparisons. If the second string starts with
2259 "{" then an encryption type is given. Default to crypt() or crypt16()
2260 (build-time choice). */
2261
2262 case ECOND_CRYPTEQ:
2263 #ifndef SUPPORT_CRYPTEQ
2264 goto COND_FAILED_NOT_COMPILED;
2265 #else
2266 if (strncmpic(sub[1], US"{md5}", 5) == 0)
2267 {
2268 int sublen = Ustrlen(sub[1]+5);
2269 md5 base;
2270 uschar digest[16];
2271
2272 md5_start(&base);
2273 md5_end(&base, (uschar *)sub[0], Ustrlen(sub[0]), digest);
2274
2275 /* If the length that we are comparing against is 24, the MD5 digest
2276 is expressed as a base64 string. This is the way LDAP does it. However,
2277 some other software uses a straightforward hex representation. We assume
2278 this if the length is 32. Other lengths fail. */
2279
2280 if (sublen == 24)
2281 {
2282 uschar *coded = auth_b64encode((uschar *)digest, 16);
2283 DEBUG(D_auth) debug_printf("crypteq: using MD5+B64 hashing\n"
2284 " subject=%s\n crypted=%s\n", coded, sub[1]+5);
2285 *yield = (Ustrcmp(coded, sub[1]+5) == 0) == testfor;
2286 }
2287 else if (sublen == 32)
2288 {
2289 int i;
2290 uschar coded[36];
2291 for (i = 0; i < 16; i++) sprintf(CS (coded+2*i), "%02X", digest[i]);
2292 coded[32] = 0;
2293 DEBUG(D_auth) debug_printf("crypteq: using MD5+hex hashing\n"
2294 " subject=%s\n crypted=%s\n", coded, sub[1]+5);
2295 *yield = (strcmpic(coded, sub[1]+5) == 0) == testfor;
2296 }
2297 else
2298 {
2299 DEBUG(D_auth) debug_printf("crypteq: length for MD5 not 24 or 32: "
2300 "fail\n crypted=%s\n", sub[1]+5);
2301 *yield = !testfor;
2302 }
2303 }
2304
2305 else if (strncmpic(sub[1], US"{sha1}", 6) == 0)
2306 {
2307 int sublen = Ustrlen(sub[1]+6);
2308 sha1 base;
2309 uschar digest[20];
2310
2311 sha1_start(&base);
2312 sha1_end(&base, (uschar *)sub[0], Ustrlen(sub[0]), digest);
2313
2314 /* If the length that we are comparing against is 28, assume the SHA1
2315 digest is expressed as a base64 string. If the length is 40, assume a
2316 straightforward hex representation. Other lengths fail. */
2317
2318 if (sublen == 28)
2319 {
2320 uschar *coded = auth_b64encode((uschar *)digest, 20);
2321 DEBUG(D_auth) debug_printf("crypteq: using SHA1+B64 hashing\n"
2322 " subject=%s\n crypted=%s\n", coded, sub[1]+6);
2323 *yield = (Ustrcmp(coded, sub[1]+6) == 0) == testfor;
2324 }
2325 else if (sublen == 40)
2326 {
2327 int i;
2328 uschar coded[44];
2329 for (i = 0; i < 20; i++) sprintf(CS (coded+2*i), "%02X", digest[i]);
2330 coded[40] = 0;
2331 DEBUG(D_auth) debug_printf("crypteq: using SHA1+hex hashing\n"
2332 " subject=%s\n crypted=%s\n", coded, sub[1]+6);
2333 *yield = (strcmpic(coded, sub[1]+6) == 0) == testfor;
2334 }
2335 else
2336 {
2337 DEBUG(D_auth) debug_printf("crypteq: length for SHA-1 not 28 or 40: "
2338 "fail\n crypted=%s\n", sub[1]+6);
2339 *yield = !testfor;
2340 }
2341 }
2342
2343 else /* {crypt} or {crypt16} and non-{ at start */
2344 /* }-for-text-editors */
2345 {
2346 int which = 0;
2347 uschar *coded;
2348
2349 if (strncmpic(sub[1], US"{crypt}", 7) == 0)
2350 {
2351 sub[1] += 7;
2352 which = 1;
2353 }
2354 else if (strncmpic(sub[1], US"{crypt16}", 9) == 0)
2355 {
2356 sub[1] += 9;
2357 which = 2;
2358 }
2359 else if (sub[1][0] == '{')
2360 {
2361 expand_string_message = string_sprintf("unknown encryption mechanism "
2362 "in \"%s\"", sub[1]);
2363 return NULL;
2364 }
2365
2366 switch(which)
2367 {
2368 case 0: coded = US DEFAULT_CRYPT(CS sub[0], CS sub[1]); break;
2369 case 1: coded = US crypt(CS sub[0], CS sub[1]); break;
2370 default: coded = US crypt16(CS sub[0], CS sub[1]); break;
2371 }
2372
2373 #define STR(s) # s
2374 #define XSTR(s) STR(s)
2375 DEBUG(D_auth) debug_printf("crypteq: using %s()\n"
2376 " subject=%s\n crypted=%s\n",
2377 (which == 0)? XSTR(DEFAULT_CRYPT) : (which == 1)? "crypt" : "crypt16",
2378 coded, sub[1]);
2379 #undef STR
2380 #undef XSTR
2381
2382 /* If the encrypted string contains fewer than two characters (for the
2383 salt), force failure. Otherwise we get false positives: with an empty
2384 string the yield of crypt() is an empty string! */
2385
2386 *yield = (Ustrlen(sub[1]) < 2)? !testfor :
2387 (Ustrcmp(coded, sub[1]) == 0) == testfor;
2388 }
2389 break;
2390 #endif /* SUPPORT_CRYPTEQ */
2391
2392 case ECOND_INLIST:
2393 case ECOND_INLISTI:
2394 {
2395 int sep = 0;
2396 BOOL found = FALSE;
2397 uschar *save_iterate_item = iterate_item;
2398 int (*compare)(const uschar *, const uschar *);
2399
2400 if (cond_type == ECOND_INLISTI)
2401 compare = strcmpic;
2402 else
2403 compare = (int (*)(const uschar *, const uschar *)) strcmp;
2404
2405 while ((iterate_item = string_nextinlist(&sub[1], &sep, NULL, 0)) != NULL)
2406 if (compare(sub[0], iterate_item) == 0)
2407 {
2408 found = TRUE;
2409 break;
2410 }
2411 iterate_item = save_iterate_item;
2412 *yield = found;
2413 }
2414
2415 } /* Switch for comparison conditions */
2416
2417 return s; /* End of comparison conditions */
2418
2419
2420 /* and/or: computes logical and/or of several conditions */
2421
2422 case ECOND_AND:
2423 case ECOND_OR:
2424 subcondptr = (yield == NULL)? NULL : &tempcond;
2425 combined_cond = (cond_type == ECOND_AND);
2426
2427 while (isspace(*s)) s++;
2428 if (*s++ != '{') goto COND_FAILED_CURLY_START;
2429
2430 for (;;)
2431 {
2432 while (isspace(*s)) s++;
2433 if (*s == '}') break;
2434 if (*s != '{')
2435 {
2436 expand_string_message = string_sprintf("each subcondition "
2437 "inside an \"%s{...}\" condition must be in its own {}", name);
2438 return NULL;
2439 }
2440
2441 s = eval_condition(s+1, subcondptr);
2442 if (s == NULL)
2443 {
2444 expand_string_message = string_sprintf("%s inside \"%s{...}\" condition",
2445 expand_string_message, name);
2446 return NULL;
2447 }
2448 while (isspace(*s)) s++;
2449
2450 if (*s++ != '}')
2451 {
2452 expand_string_message = string_sprintf("missing } at end of condition "
2453 "inside \"%s\" group", name);
2454 return NULL;
2455 }
2456
2457 if (yield != NULL)
2458 {
2459 if (cond_type == ECOND_AND)
2460 {
2461 combined_cond &= tempcond;
2462 if (!combined_cond) subcondptr = NULL; /* once false, don't */
2463 } /* evaluate any more */
2464 else
2465 {
2466 combined_cond |= tempcond;
2467 if (combined_cond) subcondptr = NULL; /* once true, don't */
2468 } /* evaluate any more */
2469 }
2470 }
2471
2472 if (yield != NULL) *yield = (combined_cond == testfor);
2473 return ++s;
2474
2475
2476 /* forall/forany: iterates a condition with different values */
2477
2478 case ECOND_FORALL:
2479 case ECOND_FORANY:
2480 {
2481 int sep = 0;
2482 uschar *save_iterate_item = iterate_item;
2483
2484 while (isspace(*s)) s++;
2485 if (*s++ != '{') goto COND_FAILED_CURLY_START;
2486 sub[0] = expand_string_internal(s, TRUE, &s, (yield == NULL), TRUE);
2487 if (sub[0] == NULL) return NULL;
2488 if (*s++ != '}') goto COND_FAILED_CURLY_END;
2489
2490 while (isspace(*s)) s++;
2491 if (*s++ != '{') goto COND_FAILED_CURLY_START;
2492
2493 sub[1] = s;
2494
2495 /* Call eval_condition once, with result discarded (as if scanning a
2496 "false" part). This allows us to find the end of the condition, because if
2497 the list it empty, we won't actually evaluate the condition for real. */
2498
2499 s = eval_condition(sub[1], NULL);
2500 if (s == NULL)
2501 {
2502 expand_string_message = string_sprintf("%s inside \"%s\" condition",
2503 expand_string_message, name);
2504 return NULL;
2505 }
2506 while (isspace(*s)) s++;
2507
2508 if (*s++ != '}')
2509 {
2510 expand_string_message = string_sprintf("missing } at end of condition "
2511 "inside \"%s\"", name);
2512 return NULL;
2513 }
2514
2515 if (yield != NULL) *yield = !testfor;
2516 while ((iterate_item = string_nextinlist(&sub[0], &sep, NULL, 0)) != NULL)
2517 {
2518 DEBUG(D_expand) debug_printf("%s: $item = \"%s\"\n", name, iterate_item);
2519 if (eval_condition(sub[1], &tempcond) == NULL)
2520 {
2521 expand_string_message = string_sprintf("%s inside \"%s\" condition",
2522 expand_string_message, name);
2523 iterate_item = save_iterate_item;
2524 return NULL;
2525 }
2526 DEBUG(D_expand) debug_printf("%s: condition evaluated to %s\n", name,
2527 tempcond? "true":"false");
2528
2529 if (yield != NULL) *yield = (tempcond == testfor);
2530 if (tempcond == (cond_type == ECOND_FORANY)) break;
2531 }
2532
2533 iterate_item = save_iterate_item;
2534 return s;
2535 }
2536
2537
2538 /* The bool{} expansion condition maps a string to boolean.
2539 The values supported should match those supported by the ACL condition
2540 (acl.c, ACLC_CONDITION) so that we keep to a minimum the different ideas
2541 of true/false. Note that Router "condition" rules have a different
2542 interpretation, where general data can be used and only a few values
2543 map to FALSE.
2544 Note that readconf.c boolean matching, for boolean configuration options,
2545 only matches true/yes/false/no.
2546 The bool_lax{} condition matches the Router logic, which is much more
2547 liberal. */
2548 case ECOND_BOOL:
2549 case ECOND_BOOL_LAX:
2550 {
2551 uschar *sub_arg[1];
2552 uschar *t, *t2;
2553 uschar *ourname;
2554 size_t len;
2555 BOOL boolvalue = FALSE;
2556 while (isspace(*s)) s++;
2557 if (*s != '{') goto COND_FAILED_CURLY_START;
2558 ourname = cond_type == ECOND_BOOL_LAX ? US"bool_lax" : US"bool";
2559 switch(read_subs(sub_arg, 1, 1, &s, yield == NULL, FALSE, ourname))
2560 {
2561 case 1: expand_string_message = string_sprintf(
2562 "too few arguments or bracketing error for %s",
2563 ourname);
2564 /*FALLTHROUGH*/
2565 case 2:
2566 case 3: return NULL;
2567 }
2568 t = sub_arg[0];
2569 while (isspace(*t)) t++;
2570 len = Ustrlen(t);
2571 if (len)
2572 {
2573 /* trailing whitespace: seems like a good idea to ignore it too */
2574 t2 = t + len - 1;
2575 while (isspace(*t2)) t2--;
2576 if (t2 != (t + len))
2577 {
2578 *++t2 = '\0';
2579 len = t2 - t;
2580 }
2581 }
2582 DEBUG(D_expand)
2583 debug_printf("considering %s: %s\n", ourname, len ? t : US"<empty>");
2584 /* logic for the lax case from expand_check_condition(), which also does
2585 expands, and the logic is both short and stable enough that there should
2586 be no maintenance burden from replicating it. */
2587 if (len == 0)
2588 boolvalue = FALSE;
2589 else if (Ustrspn(t, "0123456789") == len)
2590 {
2591 boolvalue = (Uatoi(t) == 0) ? FALSE : TRUE;
2592 /* expand_check_condition only does a literal string "0" check */
2593 if ((cond_type == ECOND_BOOL_LAX) && (len > 1))
2594 boolvalue = TRUE;
2595 }
2596 else if (strcmpic(t, US"true") == 0 || strcmpic(t, US"yes") == 0)
2597 boolvalue = TRUE;
2598 else if (strcmpic(t, US"false") == 0 || strcmpic(t, US"no") == 0)
2599 boolvalue = FALSE;
2600 else if (cond_type == ECOND_BOOL_LAX)
2601 boolvalue = TRUE;
2602 else
2603 {
2604 expand_string_message = string_sprintf("unrecognised boolean "
2605 "value \"%s\"", t);
2606 return NULL;
2607 }
2608 if (yield != NULL) *yield = (boolvalue == testfor);
2609 return s;
2610 }
2611
2612 /* Unknown condition */
2613
2614 default:
2615 expand_string_message = string_sprintf("unknown condition \"%s\"", name);
2616 return NULL;
2617 } /* End switch on condition type */
2618
2619 /* Missing braces at start and end of data */
2620
2621 COND_FAILED_CURLY_START:
2622 expand_string_message = string_sprintf("missing { after \"%s\"", name);
2623 return NULL;
2624
2625 COND_FAILED_CURLY_END:
2626 expand_string_message = string_sprintf("missing } at end of \"%s\" condition",
2627 name);
2628 return NULL;
2629
2630 /* A condition requires code that is not compiled */
2631
2632 #if !defined(SUPPORT_PAM) || !defined(RADIUS_CONFIG_FILE) || \
2633 !defined(LOOKUP_LDAP) || !defined(CYRUS_PWCHECK_SOCKET) || \
2634 !defined(SUPPORT_CRYPTEQ) || !defined(CYRUS_SASLAUTHD_SOCKET)
2635 COND_FAILED_NOT_COMPILED:
2636 expand_string_message = string_sprintf("support for \"%s\" not compiled",
2637 name);
2638 return NULL;
2639 #endif
2640 }
2641
2642
2643
2644
2645 /*************************************************
2646 * Save numerical variables *
2647 *************************************************/
2648
2649 /* This function is called from items such as "if" that want to preserve and
2650 restore the numbered variables.
2651
2652 Arguments:
2653 save_expand_string points to an array of pointers to set
2654 save_expand_nlength points to an array of ints for the lengths
2655
2656 Returns: the value of expand max to save
2657 */
2658
2659 static int
2660 save_expand_strings(uschar **save_expand_nstring, int *save_expand_nlength)
2661 {
2662 int i;
2663 for (i = 0; i <= expand_nmax; i++)
2664 {
2665 save_expand_nstring[i] = expand_nstring[i];
2666 save_expand_nlength[i] = expand_nlength[i];
2667 }
2668 return expand_nmax;
2669 }
2670
2671
2672
2673 /*************************************************
2674 * Restore numerical variables *
2675 *************************************************/
2676
2677 /* This function restored saved values of numerical strings.
2678
2679 Arguments:
2680 save_expand_nmax the number of strings to restore
2681 save_expand_string points to an array of pointers
2682 save_expand_nlength points to an array of ints
2683
2684 Returns: nothing
2685 */
2686
2687 static void
2688 restore_expand_strings(int save_expand_nmax, uschar **save_expand_nstring,
2689 int *save_expand_nlength)
2690 {
2691 int i;
2692 expand_nmax = save_expand_nmax;
2693 for (i = 0; i <= expand_nmax; i++)
2694 {
2695 expand_nstring[i] = save_expand_nstring[i];
2696 expand_nlength[i] = save_expand_nlength[i];
2697 }
2698 }
2699
2700
2701
2702
2703
2704 /*************************************************
2705 * Handle yes/no substrings *
2706 *************************************************/
2707
2708 /* This function is used by ${if}, ${lookup} and ${extract} to handle the
2709 alternative substrings that depend on whether or not the condition was true,
2710 or the lookup or extraction succeeded. The substrings always have to be
2711 expanded, to check their syntax, but "skipping" is set when the result is not
2712 needed - this avoids unnecessary nested lookups.
2713
2714 Arguments:
2715 skipping TRUE if we were skipping when this item was reached
2716 yes TRUE if the first string is to be used, else use the second
2717 save_lookup a value to put back into lookup_value before the 2nd expansion
2718 sptr points to the input string pointer
2719 yieldptr points to the output string pointer
2720 sizeptr points to the output string size
2721 ptrptr points to the output string pointer
2722 type "lookup" or "if" or "extract" or "run", for error message
2723
2724 Returns: 0 OK; lookup_value has been reset to save_lookup
2725 1 expansion failed
2726 2 expansion failed because of bracketing error
2727 */
2728
2729 static int
2730 process_yesno(BOOL skipping, BOOL yes, uschar *save_lookup, uschar **sptr,
2731 uschar **yieldptr, int *sizeptr, int *ptrptr, uschar *type)
2732 {
2733 int rc = 0;
2734 uschar *s = *sptr; /* Local value */
2735 uschar *sub1, *sub2;
2736
2737 /* If there are no following strings, we substitute the contents of $value for
2738 lookups and for extractions in the success case. For the ${if item, the string
2739 "true" is substituted. In the fail case, nothing is substituted for all three
2740 items. */
2741
2742 while (isspace(*s)) s++;
2743 if (*s == '}')
2744 {
2745 if (type[0] == 'i')
2746 {
2747 if (yes) *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, US"true", 4);
2748 }
2749 else
2750 {
2751 if (yes && lookup_value != NULL)
2752 *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, lookup_value,
2753 Ustrlen(lookup_value));
2754 lookup_value = save_lookup;
2755 }
2756 s++;
2757 goto RETURN;
2758 }
2759
2760 /* The first following string must be braced. */
2761
2762 if (*s++ != '{') goto FAILED_CURLY;
2763
2764 /* Expand the first substring. Forced failures are noticed only if we actually
2765 want this string. Set skipping in the call in the fail case (this will always
2766 be the case if we were already skipping). */
2767
2768 sub1 = expand_string_internal(s, TRUE, &s, !yes, TRUE);
2769 if (sub1 == NULL && (yes || !expand_string_forcedfail)) goto FAILED;
2770 expand_string_forcedfail = FALSE;
2771 if (*s++ != '}') goto FAILED_CURLY;
2772
2773 /* If we want the first string, add it to the output */
2774
2775 if (yes)
2776 *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, sub1, Ustrlen(sub1));
2777
2778 /* If this is called from a lookup or an extract, we want to restore $value to
2779 what it was at the start of the item, so that it has this value during the
2780 second string expansion. For the call from "if" or "run" to this function,
2781 save_lookup is set to lookup_value, so that this statement does nothing. */
2782
2783 lookup_value = save_lookup;
2784
2785 /* There now follows either another substring, or "fail", or nothing. This
2786 time, forced failures are noticed only if we want the second string. We must
2787 set skipping in the nested call if we don't want this string, or if we were
2788 already skipping. */
2789
2790 while (isspace(*s)) s++;
2791 if (*s == '{')
2792 {
2793 sub2 = expand_string_internal(s+1, TRUE, &s, yes || skipping, TRUE);
2794 if (sub2 == NULL && (!yes || !expand_string_forcedfail)) goto FAILED;
2795 expand_string_forcedfail = FALSE;
2796 if (*s++ != '}') goto FAILED_CURLY;
2797
2798 /* If we want the second string, add it to the output */
2799
2800 if (!yes)
2801 *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, sub2, Ustrlen(sub2));
2802 }
2803
2804 /* If there is no second string, but the word "fail" is present when the use of
2805 the second string is wanted, set a flag indicating it was a forced failure
2806 rather than a syntactic error. Swallow the terminating } in case this is nested
2807 inside another lookup or if or extract. */
2808
2809 else if (*s != '}')
2810 {
2811 uschar name[256];
2812 s = read_name(name, sizeof(name), s, US"_");
2813 if (Ustrcmp(name, "fail") == 0)
2814 {
2815 if (!yes && !skipping)
2816 {
2817 while (isspace(*s)) s++;
2818 if (*s++ != '}') goto FAILED_CURLY;
2819 expand_string_message =
2820 string_sprintf("\"%s\" failed and \"fail\" requested", type);
2821 expand_string_forcedfail = TRUE;
2822 goto FAILED;
2823 }
2824 }
2825 else
2826 {
2827 expand_string_message =
2828 string_sprintf("syntax error in \"%s\" item - \"fail\" expected", type);
2829 goto FAILED;
2830 }
2831 }
2832
2833 /* All we have to do now is to check on the final closing brace. */
2834
2835 while (isspace(*s)) s++;
2836 if (*s++ == '}') goto RETURN;
2837
2838 /* Get here if there is a bracketing failure */
2839
2840 FAILED_CURLY:
2841 rc++;
2842
2843 /* Get here for other failures */
2844
2845 FAILED:
2846 rc++;
2847
2848 /* Update the input pointer value before returning */
2849
2850 RETURN:
2851 *sptr = s;
2852 return rc;
2853 }
2854
2855
2856
2857
2858 /*************************************************
2859 * Handle MD5 or SHA-1 computation for HMAC *
2860 *************************************************/
2861
2862 /* These are some wrapping functions that enable the HMAC code to be a bit
2863 cleaner. A good compiler will spot the tail recursion.
2864
2865 Arguments:
2866 type HMAC_MD5 or HMAC_SHA1
2867 remaining are as for the cryptographic hash functions
2868
2869 Returns: nothing
2870 */
2871
2872 static void
2873 chash_start(int type, void *base)
2874 {
2875 if (type == HMAC_MD5)
2876 md5_start((md5 *)base);
2877 else
2878 sha1_start((sha1 *)base);
2879 }
2880
2881 static void
2882 chash_mid(int type, void *base, uschar *string)
2883 {
2884 if (type == HMAC_MD5)
2885 md5_mid((md5 *)base, string);
2886 else
2887 sha1_mid((sha1 *)base, string);
2888 }
2889
2890 static void
2891 chash_end(int type, void *base, uschar *string, int length, uschar *digest)
2892 {
2893 if (type == HMAC_MD5)
2894 md5_end((md5 *)base, string, length, digest);
2895 else
2896 sha1_end((sha1 *)base, string, length, digest);
2897 }
2898
2899
2900
2901
2902
2903 /********************************************************
2904 * prvs: Get last three digits of days since Jan 1, 1970 *
2905 ********************************************************/
2906
2907 /* This is needed to implement the "prvs" BATV reverse
2908 path signing scheme
2909
2910 Argument: integer "days" offset to add or substract to
2911 or from the current number of days.
2912
2913 Returns: pointer to string containing the last three
2914 digits of the number of days since Jan 1, 1970,
2915 modified by the offset argument, NULL if there
2916 was an error in the conversion.
2917
2918 */
2919
2920 static uschar *
2921 prvs_daystamp(int day_offset)
2922 {
2923 uschar *days = store_get(32); /* Need at least 24 for cases */
2924 (void)string_format(days, 32, TIME_T_FMT, /* where TIME_T_FMT is %lld */
2925 (time(NULL) + day_offset*86400)/86400);
2926 return (Ustrlen(days) >= 3) ? &days[Ustrlen(days)-3] : US"100";
2927 }
2928
2929
2930
2931 /********************************************************
2932 * prvs: perform HMAC-SHA1 computation of prvs bits *
2933 ********************************************************/
2934
2935 /* This is needed to implement the "prvs" BATV reverse
2936 path signing scheme
2937
2938 Arguments:
2939 address RFC2821 Address to use
2940 key The key to use (must be less than 64 characters
2941 in size)
2942 key_num Single-digit key number to use. Defaults to
2943 '0' when NULL.
2944
2945 Returns: pointer to string containing the first three
2946 bytes of the final hash in hex format, NULL if
2947 there was an error in the process.
2948 */
2949
2950 static uschar *
2951 prvs_hmac_sha1(uschar *address, uschar *key, uschar *key_num, uschar *daystamp)
2952 {
2953 uschar *hash_source, *p;
2954 int size = 0,offset = 0,i;
2955 sha1 sha1_base;
2956 void *use_base = &sha1_base;
2957 uschar innerhash[20];
2958 uschar finalhash[20];
2959 uschar innerkey[64];
2960 uschar outerkey[64];
2961 uschar *finalhash_hex = store_get(40);
2962
2963 if (key_num == NULL)
2964 key_num = US"0";
2965
2966 if (Ustrlen(key) > 64)
2967 return NULL;
2968
2969 hash_source = string_cat(NULL,&size,&offset,key_num,1);
2970 string_cat(hash_source,&size,&offset,daystamp,3);
2971 string_cat(hash_source,&size,&offset,address,Ustrlen(address));
2972 hash_source[offset] = '\0';
2973
2974 DEBUG(D_expand) debug_printf("prvs: hash source is '%s'\n", hash_source);
2975
2976 memset(innerkey, 0x36, 64);
2977 memset(outerkey, 0x5c, 64);
2978
2979 for (i = 0; i < Ustrlen(key); i++)
2980 {
2981 innerkey[i] ^= key[i];
2982 outerkey[i] ^= key[i];
2983 }
2984
2985 chash_start(HMAC_SHA1, use_base);
2986 chash_mid(HMAC_SHA1, use_base, innerkey);
2987 chash_end(HMAC_SHA1, use_base, hash_source, offset, innerhash);
2988
2989 chash_start(HMAC_SHA1, use_base);
2990 chash_mid(HMAC_SHA1, use_base, outerkey);
2991 chash_end(HMAC_SHA1, use_base, innerhash, 20, finalhash);
2992
2993 p = finalhash_hex;
2994 for (i = 0; i < 3; i++)
2995 {
2996 *p++ = hex_digits[(finalhash[i] & 0xf0) >> 4];
2997 *p++ = hex_digits[finalhash[i] & 0x0f];
2998 }
2999 *p = '\0';
3000
3001 return finalhash_hex;
3002 }
3003
3004
3005
3006
3007 /*************************************************
3008 * Join a file onto the output string *
3009 *************************************************/
3010
3011 /* This is used for readfile and after a run expansion. It joins the contents
3012 of a file onto the output string, globally replacing newlines with a given
3013 string (optionally). The file is closed at the end.
3014
3015 Arguments:
3016 f the FILE
3017 yield pointer to the expandable string
3018 sizep pointer to the current size
3019 ptrp pointer to the current position
3020 eol newline replacement string, or NULL
3021
3022 Returns: new value of string pointer
3023 */
3024
3025 static uschar *
3026 cat_file(FILE *f, uschar *yield, int *sizep, int *ptrp, uschar *eol)
3027 {
3028 int eollen;
3029 uschar buffer[1024];
3030
3031 eollen = (eol == NULL)? 0 : Ustrlen(eol);
3032
3033 while (Ufgets(buffer, sizeof(buffer), f) != NULL)
3034 {
3035 int len = Ustrlen(buffer);
3036 if (eol != NULL && buffer[len-1] == '\n') len--;
3037 yield = string_cat(yield, sizep, ptrp, buffer, len);
3038 if (buffer[len] != 0)
3039 yield = string_cat(yield, sizep, ptrp, eol, eollen);
3040 }
3041
3042 if (yield != NULL) yield[*ptrp] = 0;
3043
3044 return yield;
3045 }
3046
3047
3048
3049
3050 /*************************************************
3051 * Evaluate numeric expression *
3052 *************************************************/
3053
3054 /* This is a set of mutually recursive functions that evaluate an arithmetic
3055 expression involving + - * / % & | ^ ~ << >> and parentheses. The only one of
3056 these functions that is called from elsewhere is eval_expr, whose interface is:
3057
3058 Arguments:
3059 sptr pointer to the pointer to the string - gets updated
3060 decimal TRUE if numbers are to be assumed decimal
3061 error pointer to where to put an error message - must be NULL on input
3062 endket TRUE if ')' must terminate - FALSE for external call
3063
3064 Returns: on success: the value of the expression, with *error still NULL
3065 on failure: an undefined value, with *error = a message
3066 */
3067
3068 static int eval_op_or(uschar **, BOOL, uschar **);
3069
3070
3071 static int
3072 eval_expr(uschar **sptr, BOOL decimal, uschar **error, BOOL endket)
3073 {
3074 uschar *s = *sptr;
3075 int x = eval_op_or(&s, decimal, error);
3076 if (*error == NULL)
3077 {
3078 if (endket)
3079 {
3080 if (*s != ')')
3081 *error = US"expecting closing parenthesis";
3082 else
3083 while (isspace(*(++s)));
3084 }
3085 else if (*s != 0) *error = US"expecting operator";
3086 }
3087 *sptr = s;
3088 return x;
3089 }
3090
3091
3092 static int
3093 eval_number(uschar **sptr, BOOL decimal, uschar **error)
3094 {
3095 register int c;
3096 int n;
3097 uschar *s = *sptr;
3098 while (isspace(*s)) s++;
3099 c = *s;
3100 if (isdigit(c))
3101 {
3102 int count;
3103 (void)sscanf(CS s, (decimal? "%d%n" : "%i%n"), &n, &count);
3104 s += count;
3105 if (tolower(*s) == 'k') { n *= 1024; s++; }
3106 else if (tolower(*s) == 'm') { n *= 1024*1024; s++; }
3107 while (isspace (*s)) s++;
3108 }
3109 else if (c == '(')
3110 {
3111 s++;
3112 n = eval_expr(&s, decimal, error, 1);
3113 }
3114 else
3115 {
3116 *error = US"expecting number or opening parenthesis";
3117 n = 0;
3118 }
3119 *sptr = s;
3120 return n;
3121 }
3122
3123
3124 static int eval_op_unary(uschar **sptr, BOOL decimal, uschar **error)
3125 {
3126 uschar *s = *sptr;
3127 int x;
3128 while (isspace(*s)) s++;
3129 if (*s == '+' || *s == '-' || *s == '~')
3130 {
3131 int op = *s++;
3132 x = eval_op_unary(&s, decimal, error);
3133 if (op == '-') x = -x;
3134 else if (op == '~') x = ~x;
3135 }
3136 else
3137 {
3138 x = eval_number(&s, decimal, error);
3139 }
3140 *sptr = s;
3141 return x;
3142 }
3143
3144
3145 static int eval_op_mult(uschar **sptr, BOOL decimal, uschar **error)
3146 {
3147 uschar *s = *sptr;
3148 int x = eval_op_unary(&s, decimal, error);
3149 if (*error == NULL)
3150 {
3151 while (*s == '*' || *s == '/' || *s == '%')
3152 {
3153 int op = *s++;
3154 int y = eval_op_unary(&s, decimal, error);
3155 if (*error != NULL) break;
3156 /* SIGFPE both on div/mod by zero and on INT_MIN / -1, which would give
3157 * a value of INT_MAX+1. Note that INT_MIN * -1 gives INT_MIN for me, which
3158 * is a bug somewhere in [gcc 4.2.1, FreeBSD, amd64]. In fact, -N*-M where
3159 * -N*M is INT_MIN will yielf INT_MIN.
3160 * Since we don't support floating point, this is somewhat simpler.
3161 * Ideally, we'd return an error, but since we overflow for all other
3162 * arithmetic, consistency suggests otherwise, but what's the correct value
3163 * to use? There is none.
3164 * The C standard guarantees overflow for unsigned arithmetic but signed
3165 * overflow invokes undefined behaviour; in practice, this is overflow
3166 * except for converting INT_MIN to INT_MAX+1. We also can't guarantee
3167 * that long/longlong larger than int are available, or we could just work
3168 * with larger types. We should consider whether to guarantee 32bit eval
3169 * and 64-bit working variables, with errors returned. For now ...
3170 * So, the only SIGFPEs occur with a non-shrinking div/mod, thus -1; we
3171 * can just let the other invalid results occur otherwise, as they have
3172 * until now. For this one case, we can coerce.
3173 */
3174 if (y == -1 && x == INT_MIN && op != '*')
3175 {
3176 DEBUG(D_expand)
3177 debug_printf("Integer exception dodging: %d%c-1 coerced to %d\n",
3178 INT_MIN, op, INT_MAX);
3179 x = INT_MAX;
3180 continue;
3181 }
3182 if (op == '*')
3183 x *= y;
3184 else
3185 {
3186 if (y == 0)
3187 {
3188 *error = (op == '/') ? US"divide by zero" : US"modulo by zero";
3189 x = 0;
3190 break;
3191 }
3192 if (op == '/')
3193 x /= y;
3194 else
3195 x %= y;
3196 }
3197 }
3198 }
3199 *sptr = s;
3200 return x;
3201 }
3202
3203
3204 static int eval_op_sum(uschar **sptr, BOOL decimal, uschar **error)
3205 {
3206 uschar *s = *sptr;
3207 int x = eval_op_mult(&s, decimal, error);
3208 if (*error == NULL)
3209 {
3210 while (*s == '+' || *s == '-')
3211 {
3212 int op = *s++;
3213 int y = eval_op_mult(&s, decimal, error);
3214 if (*error != NULL) break;
3215 if (op == '+') x += y; else x -= y;
3216 }
3217 }
3218 *sptr = s;
3219 return x;
3220 }
3221
3222
3223 static int eval_op_shift(uschar **sptr, BOOL decimal, uschar **error)
3224 {
3225 uschar *s = *sptr;
3226 int x = eval_op_sum(&s, decimal, error);
3227 if (*error == NULL)
3228 {
3229 while ((*s == '<' || *s == '>') && s[1] == s[0])
3230 {
3231 int y;
3232 int op = *s++;
3233 s++;
3234 y = eval_op_sum(&s, decimal, error);
3235 if (*error != NULL) break;
3236 if (op == '<') x <<= y; else x >>= y;
3237 }
3238 }
3239 *sptr = s;
3240 return x;
3241 }
3242
3243
3244 static int eval_op_and(uschar **sptr, BOOL decimal, uschar **error)
3245 {
3246 uschar *s = *sptr;
3247 int x = eval_op_shift(&s, decimal, error);
3248 if (*error == NULL)
3249 {
3250 while (*s == '&')
3251 {
3252 int y;
3253 s++;
3254 y = eval_op_shift(&s, decimal, error);
3255 if (*error != NULL) break;
3256 x &= y;
3257 }
3258 }
3259 *sptr = s;
3260 return x;
3261 }
3262
3263
3264 static int eval_op_xor(uschar **sptr, BOOL decimal, uschar **error)
3265 {
3266 uschar *s = *sptr;
3267 int x = eval_op_and(&s, decimal, error);
3268 if (*error == NULL)
3269 {
3270 while (*s == '^')
3271 {
3272 int y;
3273 s++;
3274 y = eval_op_and(&s, decimal, error);
3275 if (*error != NULL) break;
3276 x ^= y;
3277 }
3278 }
3279 *sptr = s;
3280 return x;
3281 }
3282
3283
3284 static int eval_op_or(uschar **sptr, BOOL decimal, uschar **error)
3285 {
3286 uschar *s = *sptr;
3287 int x = eval_op_xor(&s, decimal, error);
3288 if (*error == NULL)
3289 {
3290 while (*s == '|')
3291 {
3292 int y;
3293 s++;
3294 y = eval_op_xor(&s, decimal, error);
3295 if (*error != NULL) break;
3296 x |= y;
3297 }
3298 }
3299 *sptr = s;
3300 return x;
3301 }
3302
3303
3304
3305 /*************************************************
3306 * Expand string *
3307 *************************************************/
3308
3309 /* Returns either an unchanged string, or the expanded string in stacking pool
3310 store. Interpreted sequences are:
3311
3312 \... normal escaping rules
3313 $name substitutes the variable
3314 ${name} ditto
3315 ${op:string} operates on the expanded string value
3316 ${item{arg1}{arg2}...} expands the args and then does the business
3317 some literal args are not enclosed in {}
3318
3319 There are now far too many operators and item types to make it worth listing
3320 them here in detail any more.
3321
3322 We use an internal routine recursively to handle embedded substrings. The
3323 external function follows. The yield is NULL if the expansion failed, and there
3324 are two cases: if something collapsed syntactically, or if "fail" was given
3325 as the action on a lookup failure. These can be distinguised by looking at the
3326 variable expand_string_forcedfail, which is TRUE in the latter case.
3327
3328 The skipping flag is set true when expanding a substring that isn't actually
3329 going to be used (after "if" or "lookup") and it prevents lookups from
3330 happening lower down.
3331
3332 Store usage: At start, a store block of the length of the input plus 64
3333 is obtained. This is expanded as necessary by string_cat(), which might have to
3334 get a new block, or might be able to expand the original. At the end of the
3335 function we can release any store above that portion of the yield block that
3336 was actually used. In many cases this will be optimal.
3337
3338 However: if the first item in the expansion is a variable name or header name,
3339 we reset the store before processing it; if the result is in fresh store, we
3340 use that without copying. This is helpful for expanding strings like
3341 $message_headers which can get very long.
3342
3343 There's a problem if a ${dlfunc item has side-effects that cause allocation,
3344 since resetting the store at the end of the expansion will free store that was
3345 allocated by the plugin code as well as the slop after the expanded string. So
3346 we skip any resets if ${dlfunc has been used. This is an unfortunate
3347 consequence of string expansion becoming too powerful.
3348
3349 Arguments:
3350 string the string to be expanded
3351 ket_ends true if expansion is to stop at }
3352 left if not NULL, a pointer to the first character after the
3353 expansion is placed here (typically used with ket_ends)
3354 skipping TRUE for recursive calls when the value isn't actually going
3355 to be used (to allow for optimisation)
3356 honour_dollar TRUE if $ is to be expanded,
3357 FALSE if it's just another character
3358
3359 Returns: NULL if expansion fails:
3360 expand_string_forcedfail is set TRUE if failure was forced
3361 expand_string_message contains a textual error message
3362 a pointer to the expanded string on success
3363 */
3364
3365 static uschar *
3366 expand_string_internal(uschar *string, BOOL ket_ends, uschar **left,
3367 BOOL skipping, BOOL honour_dollar)
3368 {
3369 int ptr = 0;
3370 int size = Ustrlen(string)+ 64;
3371 int item_type;
3372 uschar *yield = store_get(size);
3373 uschar *s = string;
3374 uschar *save_expand_nstring[EXPAND_MAXN+1];
3375 int save_expand_nlength[EXPAND_MAXN+1];
3376 BOOL resetok = TRUE;
3377
3378 expand_string_forcedfail = FALSE;
3379 expand_string_message = US"";
3380
3381 while (*s != 0)
3382 {
3383 uschar *value;
3384 uschar name[256];
3385
3386 /* \ escapes the next character, which must exist, or else
3387 the expansion fails. There's a special escape, \N, which causes
3388 copying of the subject verbatim up to the next \N. Otherwise,
3389 the escapes are the standard set. */
3390
3391 if (*s == '\\')
3392 {
3393 if (s[1] == 0)
3394 {
3395 expand_string_message = US"\\ at end of string";
3396 goto EXPAND_FAILED;
3397 }
3398
3399 if (s[1] == 'N')
3400 {
3401 uschar *t = s + 2;
3402 for (s = t; *s != 0; s++) if (*s == '\\' && s[1] == 'N') break;
3403 yield = string_cat(yield, &size, &ptr, t, s - t);
3404 if (*s != 0) s += 2;
3405 }
3406
3407 else
3408 {
3409 uschar ch[1];
3410 ch[0] = string_interpret_escape(&s);
3411 s++;
3412 yield = string_cat(yield, &size, &ptr, ch, 1);
3413 }
3414
3415 continue;
3416 }
3417
3418 /* Anything other than $ is just copied verbatim, unless we are
3419 looking for a terminating } character. */
3420
3421 if (ket_ends && *s == '}') break;
3422
3423 if (*s != '$' || !honour_dollar)
3424 {
3425 yield = string_cat(yield, &size, &ptr, s++, 1);
3426 continue;
3427 }
3428
3429 /* No { after the $ - must be a plain name or a number for string
3430 match variable. There has to be a fudge for variables that are the
3431 names of header fields preceded by "$header_" because header field
3432 names can contain any printing characters except space and colon.
3433 For those that don't like typing this much, "$h_" is a synonym for
3434 "$header_". A non-existent header yields a NULL value; nothing is
3435 inserted. */
3436
3437 if (isalpha((*(++s))))
3438 {
3439 int len;
3440 int newsize = 0;
3441
3442 s = read_name(name, sizeof(name), s, US"_");
3443
3444 /* If this is the first thing to be expanded, release the pre-allocated
3445 buffer. */
3446
3447 if (ptr == 0 && yield != NULL)
3448 {
3449 if (resetok) store_reset(yield);
3450 yield = NULL;
3451 size = 0;
3452 }
3453
3454 /* Header */
3455
3456 if (Ustrncmp(name, "h_", 2) == 0 ||
3457 Ustrncmp(name, "rh_", 3) == 0 ||
3458 Ustrncmp(name, "bh_", 3) == 0 ||
3459 Ustrncmp(name, "header_", 7) == 0 ||
3460 Ustrncmp(name, "rheader_", 8) == 0 ||
3461 Ustrncmp(name, "bheader_", 8) == 0)
3462 {
3463 BOOL want_raw = (name[0] == 'r')? TRUE : FALSE;
3464 uschar *charset = (name[0] == 'b')? NULL : headers_charset;
3465 s = read_header_name(name, sizeof(name), s);
3466 value = find_header(name, FALSE, &newsize, want_raw, charset);
3467
3468 /* If we didn't find the header, and the header contains a closing brace
3469 character, this may be a user error where the terminating colon
3470 has been omitted. Set a flag to adjust the error message in this case.
3471 But there is no error here - nothing gets inserted. */
3472
3473 if (value == NULL)
3474 {
3475 if (Ustrchr(name, '}') != NULL) malformed_header = TRUE;
3476 continue;
3477 }
3478 }
3479
3480 /* Variable */
3481
3482 else
3483 {
3484 value = find_variable(name, FALSE, skipping, &newsize);
3485 if (value == NULL)
3486 {
3487 expand_string_message =
3488 string_sprintf("unknown variable name \"%s\"", name);
3489 check_variable_error_message(name);
3490 goto EXPAND_FAILED;
3491 }
3492 }
3493
3494 /* If the data is known to be in a new buffer, newsize will be set to the
3495 size of that buffer. If this is the first thing in an expansion string,
3496 yield will be NULL; just point it at the new store instead of copying. Many
3497 expansion strings contain just one reference, so this is a useful
3498 optimization, especially for humungous headers. */
3499
3500 len = Ustrlen(value);
3501 if (yield == NULL && newsize != 0)
3502 {
3503 yield = value;
3504 size = newsize;
3505 ptr = len;
3506 }
3507 else yield = string_cat(yield, &size, &ptr, value, len);
3508
3509 continue;
3510 }
3511
3512 if (isdigit(*s))
3513 {
3514 int n;
3515 s = read_number(&n, s);
3516 if (n >= 0 && n <= expand_nmax)
3517 yield = string_cat(yield, &size, &ptr, expand_nstring[n],
3518 expand_nlength[n]);
3519 continue;
3520 }
3521
3522 /* Otherwise, if there's no '{' after $ it's an error. */
3523
3524 if (*s != '{')
3525 {
3526 expand_string_message = US"$ not followed by letter, digit, or {";
3527 goto EXPAND_FAILED;
3528 }
3529
3530 /* After { there can be various things, but they all start with
3531 an initial word, except for a number for a string match variable. */
3532
3533 if (isdigit((*(++s))))
3534 {
3535 int n;
3536 s = read_number(&n, s);
3537 if (*s++ != '}')
3538 {
3539 expand_string_message = US"} expected after number";
3540 goto EXPAND_FAILED;
3541 }
3542 if (n >= 0 && n <= expand_nmax)
3543 yield = string_cat(yield, &size, &ptr, expand_nstring[n],
3544 expand_nlength[n]);
3545 continue;
3546 }
3547
3548 if (!isalpha(*s))
3549 {
3550 expand_string_message = US"letter or digit expected after ${";
3551 goto EXPAND_FAILED;
3552 }
3553
3554 /* Allow "-" in names to cater for substrings with negative
3555 arguments. Since we are checking for known names after { this is
3556 OK. */
3557
3558 s = read_name(name, sizeof(name), s, US"_-");
3559 item_type = chop_match(name, item_table, sizeof(item_table)/sizeof(uschar *));
3560
3561 switch(item_type)
3562 {
3563 /* Handle conditionals - preserve the values of the numerical expansion
3564 variables in case they get changed by a regular expression match in the
3565 condition. If not, they retain their external settings. At the end
3566 of this "if" section, they get restored to their previous values. */
3567
3568 case EITEM_IF:
3569 {
3570 BOOL cond = FALSE;
3571 uschar *next_s;
3572 int save_expand_nmax =
3573 save_expand_strings(save_expand_nstring, save_expand_nlength);
3574
3575 while (isspace(*s)) s++;
3576 next_s = eval_condition(s, skipping? NULL : &cond);
3577 if (next_s == NULL) goto EXPAND_FAILED; /* message already set */
3578
3579 DEBUG(D_expand)
3580 debug_printf("condition: %.*s\n result: %s\n", (int)(next_s - s), s,
3581 cond? "true" : "false");
3582
3583 s = next_s;
3584
3585 /* The handling of "yes" and "no" result strings is now in a separate
3586 function that is also used by ${lookup} and ${extract} and ${run}. */
3587
3588 switch(process_yesno(
3589 skipping, /* were previously skipping */
3590 cond, /* success/failure indicator */
3591 lookup_value, /* value to reset for string2 */
3592 &s, /* input pointer */
3593 &yield, /* output pointer */
3594 &size, /* output size */
3595 &ptr, /* output current point */
3596 US"if")) /* condition type */
3597 {
3598 case 1: goto EXPAND_FAILED; /* when all is well, the */
3599 case 2: goto EXPAND_FAILED_CURLY; /* returned value is 0 */
3600 }
3601
3602 /* Restore external setting of expansion variables for continuation
3603 at this level. */
3604
3605 restore_expand_strings(save_expand_nmax, save_expand_nstring,
3606 save_expand_nlength);
3607 continue;
3608 }
3609
3610 /* Handle database lookups unless locked out. If "skipping" is TRUE, we are
3611 expanding an internal string that isn't actually going to be used. All we
3612 need to do is check the syntax, so don't do a lookup at all. Preserve the
3613 values of the numerical expansion variables in case they get changed by a
3614 partial lookup. If not, they retain their external settings. At the end
3615 of this "lookup" section, they get restored to their previous values. */
3616
3617 case EITEM_LOOKUP:
3618 {
3619 int stype, partial, affixlen, starflags;
3620 int expand_setup = 0;
3621 int nameptr = 0;
3622 uschar *key, *filename, *affix;
3623 uschar *save_lookup_value = lookup_value;
3624 int save_expand_nmax =
3625 save_expand_strings(save_expand_nstring, save_expand_nlength);
3626
3627 if ((expand_forbid & RDO_LOOKUP) != 0)
3628 {
3629 expand_string_message = US"lookup expansions are not permitted";
3630 goto EXPAND_FAILED;
3631 }
3632
3633 /* Get the key we are to look up for single-key+file style lookups.
3634 Otherwise set the key NULL pro-tem. */
3635
3636 while (isspace(*s)) s++;
3637 if (*s == '{')
3638 {
3639 key = expand_string_internal(s+1, TRUE, &s, skipping, TRUE);
3640 if (key == NULL) goto EXPAND_FAILED;
3641 if (*s++ != '}') goto EXPAND_FAILED_CURLY;
3642 while (isspace(*s)) s++;
3643 }
3644 else key = NULL;
3645
3646 /* Find out the type of database */
3647
3648 if (!isalpha(*s))
3649 {
3650 expand_string_message = US"missing lookup type";
3651 goto EXPAND_FAILED;
3652 }
3653
3654 /* The type is a string that may contain special characters of various
3655 kinds. Allow everything except space or { to appear; the actual content
3656 is checked by search_findtype_partial. */
3657
3658 while (*s != 0 && *s != '{' && !isspace(*s))
3659 {
3660 if (nameptr < sizeof(name) - 1) name[nameptr++] = *s;
3661 s++;
3662 }
3663 name[nameptr] = 0;
3664 while (isspace(*s)) s++;
3665
3666 /* Now check for the individual search type and any partial or default
3667 options. Only those types that are actually in the binary are valid. */
3668
3669 stype = search_findtype_partial(name, &partial, &affix, &affixlen,
3670 &starflags);
3671 if (stype < 0)
3672 {
3673 expand_string_message = search_error_message;
3674 goto EXPAND_FAILED;
3675 }
3676
3677 /* Check that a key was provided for those lookup types that need it,
3678 and was not supplied for those that use the query style. */
3679
3680 if (!mac_islookup(stype, lookup_querystyle|lookup_absfilequery))
3681 {
3682 if (key == NULL)
3683 {
3684 expand_string_message = string_sprintf("missing {key} for single-"
3685 "key \"%s\" lookup", name);
3686 goto EXPAND_FAILED;
3687 }
3688 }
3689 else
3690 {
3691 if (key != NULL)
3692 {
3693 expand_string_message = string_sprintf("a single key was given for "
3694 "lookup type \"%s\", which is not a single-key lookup type", name);
3695 goto EXPAND_FAILED;
3696 }
3697 }
3698
3699 /* Get the next string in brackets and expand it. It is the file name for
3700 single-key+file lookups, and the whole query otherwise. In the case of
3701 queries that also require a file name (e.g. sqlite), the file name comes
3702 first. */
3703
3704 if (*s != '{') goto EXPAND_FAILED_CURLY;
3705 filename = expand_string_internal(s+1, TRUE, &s, skipping, TRUE);
3706 if (filename == NULL) goto EXPAND_FAILED;
3707 if (*s++ != '}') goto EXPAND_FAILED_CURLY;
3708 while (isspace(*s)) s++;
3709
3710 /* If this isn't a single-key+file lookup, re-arrange the variables
3711 to be appropriate for the search_ functions. For query-style lookups,
3712 there is just a "key", and no file name. For the special query-style +
3713 file types, the query (i.e. "key") starts with a file name. */
3714
3715 if (key == NULL)
3716 {
3717 while (isspace(*filename)) filename++;
3718 key = filename;
3719
3720 if (mac_islookup(stype, lookup_querystyle))
3721 {
3722 filename = NULL;
3723 }
3724 else
3725 {
3726 if (*filename != '/')
3727 {
3728 expand_string_message = string_sprintf(
3729 "absolute file name expected for \"%s\" lookup", name);
3730 goto EXPAND_FAILED;
3731 }
3732 while (*key != 0 && !isspace(*key)) key++;
3733 if (*key != 0) *key++ = 0;
3734 }
3735 }
3736
3737 /* If skipping, don't do the next bit - just lookup_value == NULL, as if
3738 the entry was not found. Note that there is no search_close() function.
3739 Files are left open in case of re-use. At suitable places in higher logic,
3740 search_tidyup() is called to tidy all open files. This can save opening
3741 the same file several times. However, files may also get closed when
3742 others are opened, if too many are open at once. The rule is that a
3743 handle should not be used after a second search_open().
3744
3745 Request that a partial search sets up $1 and maybe $2 by passing
3746 expand_setup containing zero. If its value changes, reset expand_nmax,
3747 since new variables will have been set. Note that at the end of this
3748 "lookup" section, the old numeric variables are restored. */
3749
3750 if (skipping)
3751 lookup_value = NULL;
3752 else
3753 {
3754 void *handle = search_open(filename, stype, 0, NULL, NULL);
3755 if (handle == NULL)
3756 {
3757 expand_string_message = search_error_message;
3758 goto EXPAND_FAILED;
3759 }
3760 lookup_value = search_find(handle, filename, key, partial, affix,
3761 affixlen, starflags, &expand_setup);
3762 if (search_find_defer)
3763 {
3764 expand_string_message =
3765 string_sprintf("lookup of \"%s\" gave DEFER: %s",
3766 string_printing2(key, FALSE), search_error_message);
3767 goto EXPAND_FAILED;
3768 }
3769 if (expand_setup > 0) expand_nmax = expand_setup;
3770 }
3771
3772 /* The handling of "yes" and "no" result strings is now in a separate
3773 function that is also used by ${if} and ${extract}. */
3774
3775 switch(process_yesno(
3776 skipping, /* were previously skipping */
3777 lookup_value != NULL, /* success/failure indicator */
3778 save_lookup_value, /* value to reset for string2 */
3779 &s, /* input pointer */
3780 &yield, /* output pointer */
3781 &size, /* output size */
3782 &ptr, /* output current point */
3783 US"lookup")) /* condition type */
3784 {
3785 case 1: goto EXPAND_FAILED; /* when all is well, the */
3786 case 2: goto EXPAND_FAILED_CURLY; /* returned value is 0 */
3787 }
3788
3789 /* Restore external setting of expansion variables for carrying on
3790 at this level, and continue. */
3791
3792 restore_expand_strings(save_expand_nmax, save_expand_nstring,
3793 save_expand_nlength);
3794 continue;
3795 }
3796
3797 /* If Perl support is configured, handle calling embedded perl subroutines,
3798 unless locked out at this time. Syntax is ${perl{sub}} or ${perl{sub}{arg}}
3799 or ${perl{sub}{arg1}{arg2}} or up to a maximum of EXIM_PERL_MAX_ARGS
3800 arguments (defined below). */
3801
3802 #define EXIM_PERL_MAX_ARGS 8
3803
3804 case EITEM_PERL:
3805 #ifndef EXIM_PERL
3806 expand_string_message = US"\"${perl\" encountered, but this facility "
3807 "is not included in this binary";
3808 goto EXPAND_FAILED;
3809
3810 #else /* EXIM_PERL */
3811 {
3812 uschar *sub_arg[EXIM_PERL_MAX_ARGS + 2];
3813 uschar *new_yield;
3814
3815 if ((expand_forbid & RDO_PERL) != 0)
3816 {
3817 expand_string_message = US"Perl calls are not permitted";
3818 goto EXPAND_FAILED;
3819 }
3820
3821 switch(read_subs(sub_arg, EXIM_PERL_MAX_ARGS + 1, 1, &s, skipping, TRUE,
3822 US"perl"))
3823 {
3824 case 1: goto EXPAND_FAILED_CURLY;
3825 case 2:
3826 case 3: goto EXPAND_FAILED;
3827 }
3828
3829 /* If skipping, we don't actually do anything */
3830
3831 if (skipping) continue;
3832
3833 /* Start the interpreter if necessary */
3834
3835 if (!opt_perl_started)
3836 {
3837 uschar *initerror;
3838 if (opt_perl_startup == NULL)
3839 {
3840 expand_string_message = US"A setting of perl_startup is needed when "
3841 "using the Perl interpreter";
3842 goto EXPAND_FAILED;
3843 }
3844 DEBUG(D_any) debug_printf("Starting Perl interpreter\n");
3845 initerror = init_perl(opt_perl_startup);
3846 if (initerror != NULL)
3847 {
3848 expand_string_message =
3849 string_sprintf("error in perl_startup code: %s\n", initerror);
3850 goto EXPAND_FAILED;
3851 }
3852 opt_perl_started = TRUE;
3853 }
3854
3855 /* Call the function */
3856
3857 sub_arg[EXIM_PERL_MAX_ARGS + 1] = NULL;
3858 new_yield = call_perl_cat(yield, &size, &ptr, &expand_string_message,
3859 sub_arg[0], sub_arg + 1);
3860
3861 /* NULL yield indicates failure; if the message pointer has been set to
3862 NULL, the yield was undef, indicating a forced failure. Otherwise the
3863 message will indicate some kind of Perl error. */
3864
3865 if (new_yield == NULL)
3866 {
3867 if (expand_string_message == NULL)
3868 {
3869 expand_string_message =
3870 string_sprintf("Perl subroutine \"%s\" returned undef to force "
3871 "failure", sub_arg[0]);
3872 expand_string_forcedfail = TRUE;
3873 }
3874 goto EXPAND_FAILED;
3875 }
3876
3877 /* Yield succeeded. Ensure forcedfail is unset, just in case it got
3878 set during a callback from Perl. */
3879
3880 expand_string_forcedfail = FALSE;
3881 yield = new_yield;
3882 continue;
3883 }
3884 #endif /* EXIM_PERL */
3885
3886 /* Transform email address to "prvs" scheme to use
3887 as BATV-signed return path */
3888
3889 case EITEM_PRVS:
3890 {
3891 uschar *sub_arg[3];
3892 uschar *p,*domain;
3893
3894 switch(read_subs(sub_arg, 3, 2, &s, skipping, TRUE, US"prvs"))
3895 {
3896 case 1: goto EXPAND_FAILED_CURLY;
3897 case 2:
3898 case 3: goto EXPAND_FAILED;
3899 }
3900
3901 /* If skipping, we don't actually do anything */
3902 if (skipping) continue;
3903
3904 /* sub_arg[0] is the address */
3905 domain = Ustrrchr(sub_arg[0],'@');
3906 if ( (domain == NULL) || (domain == sub_arg[0]) || (Ustrlen(domain) == 1) )
3907 {
3908 expand_string_message = US"prvs first argument must be a qualified email address";
3909 goto EXPAND_FAILED;
3910 }
3911
3912 /* Calculate the hash. The second argument must be a single-digit
3913 key number, or unset. */
3914
3915 if (sub_arg[2] != NULL &&
3916 (!isdigit(sub_arg[2][0]) || sub_arg[2][1] != 0))
3917 {
3918 expand_string_message = US"prvs second argument must be a single digit";
3919 goto EXPAND_FAILED;
3920 }
3921
3922 p = prvs_hmac_sha1(sub_arg[0],sub_arg[1],sub_arg[2],prvs_daystamp(7));
3923 if (p == NULL)
3924 {
3925 expand_string_message = US"prvs hmac-sha1 conversion failed";
3926 goto EXPAND_FAILED;
3927 }
3928
3929 /* Now separate the domain from the local part */
3930 *domain++ = '\0';
3931
3932 yield = string_cat(yield,&size,&ptr,US"prvs=",5);
3933 string_cat(yield,&size,&ptr,(sub_arg[2] != NULL) ? sub_arg[2] : US"0", 1);
3934 string_cat(yield,&size,&ptr,prvs_daystamp(7),3);
3935 string_cat(yield,&size,&ptr,p,6);
3936 string_cat(yield,&size,&ptr,US"=",1);
3937 string_cat(yield,&size,&ptr,sub_arg[0],Ustrlen(sub_arg[0]));
3938 string_cat(yield,&size,&ptr,US"@",1);
3939 string_cat(yield,&size,&ptr,domain,Ustrlen(domain));
3940
3941 continue;
3942 }
3943
3944 /* Check a prvs-encoded address for validity */
3945
3946 case EITEM_PRVSCHECK:
3947 {
3948 uschar *sub_arg[3];
3949 int mysize = 0, myptr = 0;
3950 const pcre *re;
3951 uschar *p;
3952