2e59c4084e8d16990a31ff851983c5916fff10ec
[exim.git] / src / src / expand.c
1 /* $Cambridge: exim/src/src/expand.c,v 1.108 2010/06/07 08:42:15 pdp Exp $ */
2
3 /*************************************************
4 * Exim - an Internet mail transport agent *
5 *************************************************/
6
7 /* Copyright (c) University of Cambridge 1995 - 2009 */
8 /* See the file NOTICE for conditions of use and distribution. */
9
10
11 /* Functions for handling string expansion. */
12
13
14 #include "exim.h"
15
16 /* Recursively called function */
17
18 static uschar *expand_string_internal(uschar *, BOOL, uschar **, BOOL);
19
20 #ifdef STAND_ALONE
21 #ifndef SUPPORT_CRYPTEQ
22 #define SUPPORT_CRYPTEQ
23 #endif
24 #endif
25
26 #ifdef LOOKUP_LDAP
27 #include "lookups/ldap.h"
28 #endif
29
30 #ifdef SUPPORT_CRYPTEQ
31 #ifdef CRYPT_H
32 #include <crypt.h>
33 #endif
34 #ifndef HAVE_CRYPT16
35 extern char* crypt16(char*, char*);
36 #endif
37 #endif
38
39 /* The handling of crypt16() is a mess. I will record below the analysis of the
40 mess that was sent to me. We decided, however, to make changing this very low
41 priority, because in practice people are moving away from the crypt()
42 algorithms nowadays, so it doesn't seem worth it.
43
44 <quote>
45 There is an algorithm named "crypt16" in Ultrix and Tru64. It crypts
46 the first 8 characters of the password using a 20-round version of crypt
47 (standard crypt does 25 rounds). It then crypts the next 8 characters,
48 or an empty block if the password is less than 9 characters, using a
49 20-round version of crypt and the same salt as was used for the first
50 block. Charaters after the first 16 are ignored. It always generates
51 a 16-byte hash, which is expressed together with the salt as a string
52 of 24 base 64 digits. Here are some links to peruse:
53
54 http://cvs.pld.org.pl/pam/pamcrypt/crypt16.c?rev=1.2
55 http://seclists.org/bugtraq/1999/Mar/0076.html
56
57 There's a different algorithm named "bigcrypt" in HP-UX, Digital Unix,
58 and OSF/1. This is the same as the standard crypt if given a password
59 of 8 characters or less. If given more, it first does the same as crypt
60 using the first 8 characters, then crypts the next 8 (the 9th to 16th)
61 using as salt the first two base 64 digits from the first hash block.
62 If the password is more than 16 characters then it crypts the 17th to 24th
63 characters using as salt the first two base 64 digits from the second hash
64 block. And so on: I've seen references to it cutting off the password at
65 40 characters (5 blocks), 80 (10 blocks), or 128 (16 blocks). Some links:
66
67 http://cvs.pld.org.pl/pam/pamcrypt/bigcrypt.c?rev=1.2
68 http://seclists.org/bugtraq/1999/Mar/0109.html
69 http://h30097.www3.hp.com/docs/base_doc/DOCUMENTATION/HTML/AA-Q0R2D-
70 TET1_html/sec.c222.html#no_id_208
71
72 Exim has something it calls "crypt16". It will either use a native
73 crypt16 or its own implementation. A native crypt16 will presumably
74 be the one that I called "crypt16" above. The internal "crypt16"
75 function, however, is a two-block-maximum implementation of what I called
76 "bigcrypt". The documentation matches the internal code.
77
78 I suspect that whoever did the "crypt16" stuff for Exim didn't realise
79 that crypt16 and bigcrypt were different things.
80
81 Exim uses the LDAP-style scheme identifier "{crypt16}" to refer
82 to whatever it is using under that name. This unfortunately sets a
83 precedent for using "{crypt16}" to identify two incompatible algorithms
84 whose output can't be distinguished. With "{crypt16}" thus rendered
85 ambiguous, I suggest you deprecate it and invent two new identifiers
86 for the two algorithms.
87
88 Both crypt16 and bigcrypt are very poor algorithms, btw. Hashing parts
89 of the password separately means they can be cracked separately, so
90 the double-length hash only doubles the cracking effort instead of
91 squaring it. I recommend salted SHA-1 ({SSHA}), or the Blowfish-based
92 bcrypt ({CRYPT}$2a$).
93 </quote>
94 */
95
96
97
98
99 /*************************************************
100 * Local statics and tables *
101 *************************************************/
102
103 /* Table of item names, and corresponding switch numbers. The names must be in
104 alphabetical order. */
105
106 static uschar *item_table[] = {
107 US"dlfunc",
108 US"extract",
109 US"filter",
110 US"hash",
111 US"hmac",
112 US"if",
113 US"length",
114 US"lookup",
115 US"map",
116 US"nhash",
117 US"perl",
118 US"prvs",
119 US"prvscheck",
120 US"readfile",
121 US"readsocket",
122 US"reduce",
123 US"run",
124 US"sg",
125 US"substr",
126 US"tr" };
127
128 enum {
129 EITEM_DLFUNC,
130 EITEM_EXTRACT,
131 EITEM_FILTER,
132 EITEM_HASH,
133 EITEM_HMAC,
134 EITEM_IF,
135 EITEM_LENGTH,
136 EITEM_LOOKUP,
137 EITEM_MAP,
138 EITEM_NHASH,
139 EITEM_PERL,
140 EITEM_PRVS,
141 EITEM_PRVSCHECK,
142 EITEM_READFILE,
143 EITEM_READSOCK,
144 EITEM_REDUCE,
145 EITEM_RUN,
146 EITEM_SG,
147 EITEM_SUBSTR,
148 EITEM_TR };
149
150 /* Tables of operator names, and corresponding switch numbers. The names must be
151 in alphabetical order. There are two tables, because underscore is used in some
152 cases to introduce arguments, whereas for other it is part of the name. This is
153 an historical mis-design. */
154
155 static uschar *op_table_underscore[] = {
156 US"from_utf8",
157 US"local_part",
158 US"quote_local_part",
159 US"reverse_ip",
160 US"time_eval",
161 US"time_interval"};
162
163 enum {
164 EOP_FROM_UTF8,
165 EOP_LOCAL_PART,
166 EOP_QUOTE_LOCAL_PART,
167 EOP_REVERSE_IP,
168 EOP_TIME_EVAL,
169 EOP_TIME_INTERVAL };
170
171 static uschar *op_table_main[] = {
172 US"address",
173 US"addresses",
174 US"base62",
175 US"base62d",
176 US"domain",
177 US"escape",
178 US"eval",
179 US"eval10",
180 US"expand",
181 US"h",
182 US"hash",
183 US"hex2b64",
184 US"l",
185 US"lc",
186 US"length",
187 US"mask",
188 US"md5",
189 US"nh",
190 US"nhash",
191 US"quote",
192 US"randint",
193 US"rfc2047",
194 US"rfc2047d",
195 US"rxquote",
196 US"s",
197 US"sha1",
198 US"stat",
199 US"str2b64",
200 US"strlen",
201 US"substr",
202 US"uc" };
203
204 enum {
205 EOP_ADDRESS = sizeof(op_table_underscore)/sizeof(uschar *),
206 EOP_ADDRESSES,
207 EOP_BASE62,
208 EOP_BASE62D,
209 EOP_DOMAIN,
210 EOP_ESCAPE,
211 EOP_EVAL,
212 EOP_EVAL10,
213 EOP_EXPAND,
214 EOP_H,
215 EOP_HASH,
216 EOP_HEX2B64,
217 EOP_L,
218 EOP_LC,
219 EOP_LENGTH,
220 EOP_MASK,
221 EOP_MD5,
222 EOP_NH,
223 EOP_NHASH,
224 EOP_QUOTE,
225 EOP_RANDINT,
226 EOP_RFC2047,
227 EOP_RFC2047D,
228 EOP_RXQUOTE,
229 EOP_S,
230 EOP_SHA1,
231 EOP_STAT,
232 EOP_STR2B64,
233 EOP_STRLEN,
234 EOP_SUBSTR,
235 EOP_UC };
236
237
238 /* Table of condition names, and corresponding switch numbers. The names must
239 be in alphabetical order. */
240
241 static uschar *cond_table[] = {
242 US"<",
243 US"<=",
244 US"=",
245 US"==", /* Backward compatibility */
246 US">",
247 US">=",
248 US"and",
249 US"bool",
250 US"bool_lax",
251 US"crypteq",
252 US"def",
253 US"eq",
254 US"eqi",
255 US"exists",
256 US"first_delivery",
257 US"forall",
258 US"forany",
259 US"ge",
260 US"gei",
261 US"gt",
262 US"gti",
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_ISIP,
307 ECOND_ISIP4,
308 ECOND_ISIP6,
309 ECOND_LDAPAUTH,
310 ECOND_STR_LE,
311 ECOND_STR_LEI,
312 ECOND_STR_LT,
313 ECOND_STR_LTI,
314 ECOND_MATCH,
315 ECOND_MATCH_ADDRESS,
316 ECOND_MATCH_DOMAIN,
317 ECOND_MATCH_IP,
318 ECOND_MATCH_LOCAL_PART,
319 ECOND_OR,
320 ECOND_PAM,
321 ECOND_PWCHECK,
322 ECOND_QUEUE_RUNNING,
323 ECOND_RADIUS,
324 ECOND_SASLAUTHD
325 };
326
327
328 /* Type for main variable table */
329
330 typedef struct {
331 const char *name;
332 int type;
333 void *value;
334 } var_entry;
335
336 /* Type for entries pointing to address/length pairs. Not currently
337 in use. */
338
339 typedef struct {
340 uschar **address;
341 int *length;
342 } alblock;
343
344 /* Types of table entry */
345
346 enum {
347 vtype_int, /* value is address of int */
348 vtype_filter_int, /* ditto, but recognized only when filtering */
349 vtype_ino, /* value is address of ino_t (not always an int) */
350 vtype_uid, /* value is address of uid_t (not always an int) */
351 vtype_gid, /* value is address of gid_t (not always an int) */
352 vtype_stringptr, /* value is address of pointer to string */
353 vtype_msgbody, /* as stringptr, but read when first required */
354 vtype_msgbody_end, /* ditto, the end of the message */
355 vtype_msgheaders, /* the message's headers, processed */
356 vtype_msgheaders_raw, /* the message's headers, unprocessed */
357 vtype_localpart, /* extract local part from string */
358 vtype_domain, /* extract domain from string */
359 vtype_recipients, /* extract recipients from recipients list */
360 /* (available only in system filters, ACLs, and */
361 /* local_scan()) */
362 vtype_todbsdin, /* value not used; generate BSD inbox tod */
363 vtype_tode, /* value not used; generate tod in epoch format */
364 vtype_todf, /* value not used; generate full tod */
365 vtype_todl, /* value not used; generate log tod */
366 vtype_todlf, /* value not used; generate log file datestamp tod */
367 vtype_todzone, /* value not used; generate time zone only */
368 vtype_todzulu, /* value not used; generate zulu tod */
369 vtype_reply, /* value not used; get reply from headers */
370 vtype_pid, /* value not used; result is pid */
371 vtype_host_lookup, /* value not used; get host name */
372 vtype_load_avg, /* value not used; result is int from os_getloadavg */
373 vtype_pspace, /* partition space; value is T/F for spool/log */
374 vtype_pinodes /* partition inodes; value is T/F for spool/log */
375 #ifndef DISABLE_DKIM
376 ,vtype_dkim /* Lookup of value in DKIM signature */
377 #endif
378 };
379
380 /* This table must be kept in alphabetical order. */
381
382 static var_entry var_table[] = {
383 /* WARNING: Do not invent variables whose names start acl_c or acl_m because
384 they will be confused with user-creatable ACL variables. */
385 { "acl_verify_message", vtype_stringptr, &acl_verify_message },
386 { "address_data", vtype_stringptr, &deliver_address_data },
387 { "address_file", vtype_stringptr, &address_file },
388 { "address_pipe", vtype_stringptr, &address_pipe },
389 { "authenticated_id", vtype_stringptr, &authenticated_id },
390 { "authenticated_sender",vtype_stringptr, &authenticated_sender },
391 { "authentication_failed",vtype_int, &authentication_failed },
392 #ifdef EXPERIMENTAL_BRIGHTMAIL
393 { "bmi_alt_location", vtype_stringptr, &bmi_alt_location },
394 { "bmi_base64_tracker_verdict", vtype_stringptr, &bmi_base64_tracker_verdict },
395 { "bmi_base64_verdict", vtype_stringptr, &bmi_base64_verdict },
396 { "bmi_deliver", vtype_int, &bmi_deliver },
397 #endif
398 { "body_linecount", vtype_int, &body_linecount },
399 { "body_zerocount", vtype_int, &body_zerocount },
400 { "bounce_recipient", vtype_stringptr, &bounce_recipient },
401 { "bounce_return_size_limit", vtype_int, &bounce_return_size_limit },
402 { "caller_gid", vtype_gid, &real_gid },
403 { "caller_uid", vtype_uid, &real_uid },
404 { "compile_date", vtype_stringptr, &version_date },
405 { "compile_number", vtype_stringptr, &version_cnumber },
406 { "csa_status", vtype_stringptr, &csa_status },
407 #ifdef EXPERIMENTAL_DCC
408 { "dcc_header", vtype_stringptr, &dcc_header },
409 { "dcc_result", vtype_stringptr, &dcc_result },
410 #endif
411 #ifdef WITH_OLD_DEMIME
412 { "demime_errorlevel", vtype_int, &demime_errorlevel },
413 { "demime_reason", vtype_stringptr, &demime_reason },
414 #endif
415 #ifndef DISABLE_DKIM
416 { "dkim_algo", vtype_dkim, (void *)DKIM_ALGO },
417 { "dkim_bodylength", vtype_dkim, (void *)DKIM_BODYLENGTH },
418 { "dkim_canon_body", vtype_dkim, (void *)DKIM_CANON_BODY },
419 { "dkim_canon_headers", vtype_dkim, (void *)DKIM_CANON_HEADERS },
420 { "dkim_copiedheaders", vtype_dkim, (void *)DKIM_COPIEDHEADERS },
421 { "dkim_created", vtype_dkim, (void *)DKIM_CREATED },
422 { "dkim_cur_signer", vtype_stringptr, &dkim_cur_signer },
423 { "dkim_domain", vtype_stringptr, &dkim_signing_domain },
424 { "dkim_expires", vtype_dkim, (void *)DKIM_EXPIRES },
425 { "dkim_headernames", vtype_dkim, (void *)DKIM_HEADERNAMES },
426 { "dkim_identity", vtype_dkim, (void *)DKIM_IDENTITY },
427 { "dkim_key_granularity",vtype_dkim, (void *)DKIM_KEY_GRANULARITY },
428 { "dkim_key_nosubdomains",vtype_dkim, (void *)DKIM_NOSUBDOMAINS },
429 { "dkim_key_notes", vtype_dkim, (void *)DKIM_KEY_NOTES },
430 { "dkim_key_srvtype", vtype_dkim, (void *)DKIM_KEY_SRVTYPE },
431 { "dkim_key_testing", vtype_dkim, (void *)DKIM_KEY_TESTING },
432 { "dkim_selector", vtype_stringptr, &dkim_signing_selector },
433 { "dkim_signers", vtype_stringptr, &dkim_signers },
434 { "dkim_verify_reason", vtype_dkim, (void *)DKIM_VERIFY_REASON },
435 { "dkim_verify_status", vtype_dkim, (void *)DKIM_VERIFY_STATUS},
436 #endif
437 { "dnslist_domain", vtype_stringptr, &dnslist_domain },
438 { "dnslist_matched", vtype_stringptr, &dnslist_matched },
439 { "dnslist_text", vtype_stringptr, &dnslist_text },
440 { "dnslist_value", vtype_stringptr, &dnslist_value },
441 { "domain", vtype_stringptr, &deliver_domain },
442 { "domain_data", vtype_stringptr, &deliver_domain_data },
443 { "exim_gid", vtype_gid, &exim_gid },
444 { "exim_path", vtype_stringptr, &exim_path },
445 { "exim_uid", vtype_uid, &exim_uid },
446 #ifdef WITH_OLD_DEMIME
447 { "found_extension", vtype_stringptr, &found_extension },
448 #endif
449 { "home", vtype_stringptr, &deliver_home },
450 { "host", vtype_stringptr, &deliver_host },
451 { "host_address", vtype_stringptr, &deliver_host_address },
452 { "host_data", vtype_stringptr, &host_data },
453 { "host_lookup_deferred",vtype_int, &host_lookup_deferred },
454 { "host_lookup_failed", vtype_int, &host_lookup_failed },
455 { "inode", vtype_ino, &deliver_inode },
456 { "interface_address", vtype_stringptr, &interface_address },
457 { "interface_port", vtype_int, &interface_port },
458 { "item", vtype_stringptr, &iterate_item },
459 #ifdef LOOKUP_LDAP
460 { "ldap_dn", vtype_stringptr, &eldap_dn },
461 #endif
462 { "load_average", vtype_load_avg, NULL },
463 { "local_part", vtype_stringptr, &deliver_localpart },
464 { "local_part_data", vtype_stringptr, &deliver_localpart_data },
465 { "local_part_prefix", vtype_stringptr, &deliver_localpart_prefix },
466 { "local_part_suffix", vtype_stringptr, &deliver_localpart_suffix },
467 { "local_scan_data", vtype_stringptr, &local_scan_data },
468 { "local_user_gid", vtype_gid, &local_user_gid },
469 { "local_user_uid", vtype_uid, &local_user_uid },
470 { "localhost_number", vtype_int, &host_number },
471 { "log_inodes", vtype_pinodes, (void *)FALSE },
472 { "log_space", vtype_pspace, (void *)FALSE },
473 { "mailstore_basename", vtype_stringptr, &mailstore_basename },
474 #ifdef WITH_CONTENT_SCAN
475 { "malware_name", vtype_stringptr, &malware_name },
476 #endif
477 { "max_received_linelength", vtype_int, &max_received_linelength },
478 { "message_age", vtype_int, &message_age },
479 { "message_body", vtype_msgbody, &message_body },
480 { "message_body_end", vtype_msgbody_end, &message_body_end },
481 { "message_body_size", vtype_int, &message_body_size },
482 { "message_exim_id", vtype_stringptr, &message_id },
483 { "message_headers", vtype_msgheaders, NULL },
484 { "message_headers_raw", vtype_msgheaders_raw, NULL },
485 { "message_id", vtype_stringptr, &message_id },
486 { "message_linecount", vtype_int, &message_linecount },
487 { "message_size", vtype_int, &message_size },
488 #ifdef WITH_CONTENT_SCAN
489 { "mime_anomaly_level", vtype_int, &mime_anomaly_level },
490 { "mime_anomaly_text", vtype_stringptr, &mime_anomaly_text },
491 { "mime_boundary", vtype_stringptr, &mime_boundary },
492 { "mime_charset", vtype_stringptr, &mime_charset },
493 { "mime_content_description", vtype_stringptr, &mime_content_description },
494 { "mime_content_disposition", vtype_stringptr, &mime_content_disposition },
495 { "mime_content_id", vtype_stringptr, &mime_content_id },
496 { "mime_content_size", vtype_int, &mime_content_size },
497 { "mime_content_transfer_encoding",vtype_stringptr, &mime_content_transfer_encoding },
498 { "mime_content_type", vtype_stringptr, &mime_content_type },
499 { "mime_decoded_filename", vtype_stringptr, &mime_decoded_filename },
500 { "mime_filename", vtype_stringptr, &mime_filename },
501 { "mime_is_coverletter", vtype_int, &mime_is_coverletter },
502 { "mime_is_multipart", vtype_int, &mime_is_multipart },
503 { "mime_is_rfc822", vtype_int, &mime_is_rfc822 },
504 { "mime_part_count", vtype_int, &mime_part_count },
505 #endif
506 { "n0", vtype_filter_int, &filter_n[0] },
507 { "n1", vtype_filter_int, &filter_n[1] },
508 { "n2", vtype_filter_int, &filter_n[2] },
509 { "n3", vtype_filter_int, &filter_n[3] },
510 { "n4", vtype_filter_int, &filter_n[4] },
511 { "n5", vtype_filter_int, &filter_n[5] },
512 { "n6", vtype_filter_int, &filter_n[6] },
513 { "n7", vtype_filter_int, &filter_n[7] },
514 { "n8", vtype_filter_int, &filter_n[8] },
515 { "n9", vtype_filter_int, &filter_n[9] },
516 { "original_domain", vtype_stringptr, &deliver_domain_orig },
517 { "original_local_part", vtype_stringptr, &deliver_localpart_orig },
518 { "originator_gid", vtype_gid, &originator_gid },
519 { "originator_uid", vtype_uid, &originator_uid },
520 { "parent_domain", vtype_stringptr, &deliver_domain_parent },
521 { "parent_local_part", vtype_stringptr, &deliver_localpart_parent },
522 { "pid", vtype_pid, NULL },
523 { "primary_hostname", vtype_stringptr, &primary_hostname },
524 { "prvscheck_address", vtype_stringptr, &prvscheck_address },
525 { "prvscheck_keynum", vtype_stringptr, &prvscheck_keynum },
526 { "prvscheck_result", vtype_stringptr, &prvscheck_result },
527 { "qualify_domain", vtype_stringptr, &qualify_domain_sender },
528 { "qualify_recipient", vtype_stringptr, &qualify_domain_recipient },
529 { "rcpt_count", vtype_int, &rcpt_count },
530 { "rcpt_defer_count", vtype_int, &rcpt_defer_count },
531 { "rcpt_fail_count", vtype_int, &rcpt_fail_count },
532 { "received_count", vtype_int, &received_count },
533 { "received_for", vtype_stringptr, &received_for },
534 { "received_ip_address", vtype_stringptr, &interface_address },
535 { "received_port", vtype_int, &interface_port },
536 { "received_protocol", vtype_stringptr, &received_protocol },
537 { "received_time", vtype_int, &received_time },
538 { "recipient_data", vtype_stringptr, &recipient_data },
539 { "recipient_verify_failure",vtype_stringptr,&recipient_verify_failure },
540 { "recipients", vtype_recipients, NULL },
541 { "recipients_count", vtype_int, &recipients_count },
542 #ifdef WITH_CONTENT_SCAN
543 { "regex_match_string", vtype_stringptr, &regex_match_string },
544 #endif
545 { "reply_address", vtype_reply, NULL },
546 { "return_path", vtype_stringptr, &return_path },
547 { "return_size_limit", vtype_int, &bounce_return_size_limit },
548 { "runrc", vtype_int, &runrc },
549 { "self_hostname", vtype_stringptr, &self_hostname },
550 { "sender_address", vtype_stringptr, &sender_address },
551 { "sender_address_data", vtype_stringptr, &sender_address_data },
552 { "sender_address_domain", vtype_domain, &sender_address },
553 { "sender_address_local_part", vtype_localpart, &sender_address },
554 { "sender_data", vtype_stringptr, &sender_data },
555 { "sender_fullhost", vtype_stringptr, &sender_fullhost },
556 { "sender_helo_name", vtype_stringptr, &sender_helo_name },
557 { "sender_host_address", vtype_stringptr, &sender_host_address },
558 { "sender_host_authenticated",vtype_stringptr, &sender_host_authenticated },
559 { "sender_host_name", vtype_host_lookup, NULL },
560 { "sender_host_port", vtype_int, &sender_host_port },
561 { "sender_ident", vtype_stringptr, &sender_ident },
562 { "sender_rate", vtype_stringptr, &sender_rate },
563 { "sender_rate_limit", vtype_stringptr, &sender_rate_limit },
564 { "sender_rate_period", vtype_stringptr, &sender_rate_period },
565 { "sender_rcvhost", vtype_stringptr, &sender_rcvhost },
566 { "sender_verify_failure",vtype_stringptr, &sender_verify_failure },
567 { "sending_ip_address", vtype_stringptr, &sending_ip_address },
568 { "sending_port", vtype_int, &sending_port },
569 { "smtp_active_hostname", vtype_stringptr, &smtp_active_hostname },
570 { "smtp_command", vtype_stringptr, &smtp_cmd_buffer },
571 { "smtp_command_argument", vtype_stringptr, &smtp_cmd_argument },
572 { "smtp_count_at_connection_start", vtype_int, &smtp_accept_count },
573 { "smtp_notquit_reason", vtype_stringptr, &smtp_notquit_reason },
574 { "sn0", vtype_filter_int, &filter_sn[0] },
575 { "sn1", vtype_filter_int, &filter_sn[1] },
576 { "sn2", vtype_filter_int, &filter_sn[2] },
577 { "sn3", vtype_filter_int, &filter_sn[3] },
578 { "sn4", vtype_filter_int, &filter_sn[4] },
579 { "sn5", vtype_filter_int, &filter_sn[5] },
580 { "sn6", vtype_filter_int, &filter_sn[6] },
581 { "sn7", vtype_filter_int, &filter_sn[7] },
582 { "sn8", vtype_filter_int, &filter_sn[8] },
583 { "sn9", vtype_filter_int, &filter_sn[9] },
584 #ifdef WITH_CONTENT_SCAN
585 { "spam_bar", vtype_stringptr, &spam_bar },
586 { "spam_report", vtype_stringptr, &spam_report },
587 { "spam_score", vtype_stringptr, &spam_score },
588 { "spam_score_int", vtype_stringptr, &spam_score_int },
589 #endif
590 #ifdef EXPERIMENTAL_SPF
591 { "spf_guess", vtype_stringptr, &spf_guess },
592 { "spf_header_comment", vtype_stringptr, &spf_header_comment },
593 { "spf_received", vtype_stringptr, &spf_received },
594 { "spf_result", vtype_stringptr, &spf_result },
595 { "spf_smtp_comment", vtype_stringptr, &spf_smtp_comment },
596 #endif
597 { "spool_directory", vtype_stringptr, &spool_directory },
598 { "spool_inodes", vtype_pinodes, (void *)TRUE },
599 { "spool_space", vtype_pspace, (void *)TRUE },
600 #ifdef EXPERIMENTAL_SRS
601 { "srs_db_address", vtype_stringptr, &srs_db_address },
602 { "srs_db_key", vtype_stringptr, &srs_db_key },
603 { "srs_orig_recipient", vtype_stringptr, &srs_orig_recipient },
604 { "srs_orig_sender", vtype_stringptr, &srs_orig_sender },
605 { "srs_recipient", vtype_stringptr, &srs_recipient },
606 { "srs_status", vtype_stringptr, &srs_status },
607 #endif
608 { "thisaddress", vtype_stringptr, &filter_thisaddress },
609 { "tls_certificate_verified", vtype_int, &tls_certificate_verified },
610 { "tls_cipher", vtype_stringptr, &tls_cipher },
611 { "tls_peerdn", vtype_stringptr, &tls_peerdn },
612 { "tod_bsdinbox", vtype_todbsdin, NULL },
613 { "tod_epoch", vtype_tode, NULL },
614 { "tod_full", vtype_todf, NULL },
615 { "tod_log", vtype_todl, NULL },
616 { "tod_logfile", vtype_todlf, NULL },
617 { "tod_zone", vtype_todzone, NULL },
618 { "tod_zulu", vtype_todzulu, NULL },
619 { "value", vtype_stringptr, &lookup_value },
620 { "version_number", vtype_stringptr, &version_string },
621 { "warn_message_delay", vtype_stringptr, &warnmsg_delay },
622 { "warn_message_recipient",vtype_stringptr, &warnmsg_recipients },
623 { "warn_message_recipients",vtype_stringptr,&warnmsg_recipients },
624 { "warnmsg_delay", vtype_stringptr, &warnmsg_delay },
625 { "warnmsg_recipient", vtype_stringptr, &warnmsg_recipients },
626 { "warnmsg_recipients", vtype_stringptr, &warnmsg_recipients }
627 };
628
629 static int var_table_size = sizeof(var_table)/sizeof(var_entry);
630 static uschar var_buffer[256];
631 static BOOL malformed_header;
632
633 /* For textual hashes */
634
635 static const char *hashcodes = "abcdefghijklmnopqrtsuvwxyz"
636 "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
637 "0123456789";
638
639 enum { HMAC_MD5, HMAC_SHA1 };
640
641 /* For numeric hashes */
642
643 static unsigned int prime[] = {
644 2, 3, 5, 7, 11, 13, 17, 19, 23, 29,
645 31, 37, 41, 43, 47, 53, 59, 61, 67, 71,
646 73, 79, 83, 89, 97, 101, 103, 107, 109, 113};
647
648 /* For printing modes in symbolic form */
649
650 static uschar *mtable_normal[] =
651 { US"---", US"--x", US"-w-", US"-wx", US"r--", US"r-x", US"rw-", US"rwx" };
652
653 static uschar *mtable_setid[] =
654 { US"--S", US"--s", US"-wS", US"-ws", US"r-S", US"r-s", US"rwS", US"rws" };
655
656 static uschar *mtable_sticky[] =
657 { US"--T", US"--t", US"-wT", US"-wt", US"r-T", US"r-t", US"rwT", US"rwt" };
658
659
660
661 /*************************************************
662 * Tables for UTF-8 support *
663 *************************************************/
664
665 /* Table of the number of extra characters, indexed by the first character
666 masked with 0x3f. The highest number for a valid UTF-8 character is in fact
667 0x3d. */
668
669 static uschar utf8_table1[] = {
670 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
671 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
672 2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
673 3,3,3,3,3,3,3,3,4,4,4,4,5,5,5,5 };
674
675 /* These are the masks for the data bits in the first byte of a character,
676 indexed by the number of additional bytes. */
677
678 static int utf8_table2[] = { 0xff, 0x1f, 0x0f, 0x07, 0x03, 0x01};
679
680 /* Get the next UTF-8 character, advancing the pointer. */
681
682 #define GETUTF8INC(c, ptr) \
683 c = *ptr++; \
684 if ((c & 0xc0) == 0xc0) \
685 { \
686 int a = utf8_table1[c & 0x3f]; /* Number of additional bytes */ \
687 int s = 6*a; \
688 c = (c & utf8_table2[a]) << s; \
689 while (a-- > 0) \
690 { \
691 s -= 6; \
692 c |= (*ptr++ & 0x3f) << s; \
693 } \
694 }
695
696
697 /*************************************************
698 * Binary chop search on a table *
699 *************************************************/
700
701 /* This is used for matching expansion items and operators.
702
703 Arguments:
704 name the name that is being sought
705 table the table to search
706 table_size the number of items in the table
707
708 Returns: the offset in the table, or -1
709 */
710
711 static int
712 chop_match(uschar *name, uschar **table, int table_size)
713 {
714 uschar **bot = table;
715 uschar **top = table + table_size;
716
717 while (top > bot)
718 {
719 uschar **mid = bot + (top - bot)/2;
720 int c = Ustrcmp(name, *mid);
721 if (c == 0) return mid - table;
722 if (c > 0) bot = mid + 1; else top = mid;
723 }
724
725 return -1;
726 }
727
728
729
730 /*************************************************
731 * Check a condition string *
732 *************************************************/
733
734 /* This function is called to expand a string, and test the result for a "true"
735 or "false" value. Failure of the expansion yields FALSE; logged unless it was a
736 forced fail or lookup defer. All store used by the function can be released on
737 exit.
738
739 The actual false-value tests should be replicated for ECOND_BOOL_LAX.
740
741 Arguments:
742 condition the condition string
743 m1 text to be incorporated in panic error
744 m2 ditto
745
746 Returns: TRUE if condition is met, FALSE if not
747 */
748
749 BOOL
750 expand_check_condition(uschar *condition, uschar *m1, uschar *m2)
751 {
752 int rc;
753 void *reset_point = store_get(0);
754 uschar *ss = expand_string(condition);
755 if (ss == NULL)
756 {
757 if (!expand_string_forcedfail && !search_find_defer)
758 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand condition \"%s\" "
759 "for %s %s: %s", condition, m1, m2, expand_string_message);
760 return FALSE;
761 }
762 rc = ss[0] != 0 && Ustrcmp(ss, "0") != 0 && strcmpic(ss, US"no") != 0 &&
763 strcmpic(ss, US"false") != 0;
764 store_reset(reset_point);
765 return rc;
766 }
767
768
769
770 /*************************************************
771 * Pseudo-random number generation *
772 *************************************************/
773
774 /* Pseudo-random number generation. The result is not "expected" to be
775 cryptographically strong but not so weak that someone will shoot themselves
776 in the foot using it as a nonce in some email header scheme or whatever
777 weirdness they'll twist this into. The result should ideally handle fork().
778
779 However, if we're stuck unable to provide this, then we'll fall back to
780 appallingly bad randomness.
781
782 If SUPPORT_TLS is defined and OpenSSL is used, then this will not be used.
783 The GNUTLS randomness functions found do not seem amenable to extracting
784 random numbers outside of a TLS context. Any volunteers?
785
786 Arguments:
787 max range maximum
788 Returns a random number in range [0, max-1]
789 */
790
791 #if !defined(SUPPORT_TLS) || defined(USE_GNUTLS)
792 int
793 pseudo_random_number(int max)
794 {
795 static pid_t pid = 0;
796 pid_t p2;
797 #if defined(HAVE_SRANDOM) && !defined(HAVE_SRANDOMDEV)
798 struct timeval tv;
799 #endif
800
801 p2 = getpid();
802 if (p2 != pid)
803 {
804 if (pid != 0)
805 {
806
807 #ifdef HAVE_ARC4RANDOM
808 /* cryptographically strong randomness, common on *BSD platforms, not
809 so much elsewhere. Alas. */
810 arc4random_stir();
811 #elif defined(HAVE_SRANDOM) || defined(HAVE_SRANDOMDEV)
812 #ifdef HAVE_SRANDOMDEV
813 /* uses random(4) for seeding */
814 srandomdev();
815 #else
816 gettimeofday(&tv, NULL);
817 srandom(tv.tv_sec | tv.tv_usec | getpid());
818 #endif
819 #else
820 /* Poor randomness and no seeding here */
821 #endif
822
823 }
824 pid = p2;
825 }
826
827 #ifdef HAVE_ARC4RANDOM
828 return arc4random() % max;
829 #elif defined(HAVE_SRANDOM) || defined(HAVE_SRANDOMDEV)
830 return random() % max;
831 #else
832 /* This one returns a 16-bit number, definitely not crypto-strong */
833 return random_number(max);
834 #endif
835 }
836
837 #endif
838
839 /*************************************************
840 * Pick out a name from a string *
841 *************************************************/
842
843 /* If the name is too long, it is silently truncated.
844
845 Arguments:
846 name points to a buffer into which to put the name
847 max is the length of the buffer
848 s points to the first alphabetic character of the name
849 extras chars other than alphanumerics to permit
850
851 Returns: pointer to the first character after the name
852
853 Note: The test for *s != 0 in the while loop is necessary because
854 Ustrchr() yields non-NULL if the character is zero (which is not something
855 I expected). */
856
857 static uschar *
858 read_name(uschar *name, int max, uschar *s, uschar *extras)
859 {
860 int ptr = 0;
861 while (*s != 0 && (isalnum(*s) || Ustrchr(extras, *s) != NULL))
862 {
863 if (ptr < max-1) name[ptr++] = *s;
864 s++;
865 }
866 name[ptr] = 0;
867 return s;
868 }
869
870
871
872 /*************************************************
873 * Pick out the rest of a header name *
874 *************************************************/
875
876 /* A variable name starting $header_ (or just $h_ for those who like
877 abbreviations) might not be the complete header name because headers can
878 contain any printing characters in their names, except ':'. This function is
879 called to read the rest of the name, chop h[eader]_ off the front, and put ':'
880 on the end, if the name was terminated by white space.
881
882 Arguments:
883 name points to a buffer in which the name read so far exists
884 max is the length of the buffer
885 s points to the first character after the name so far, i.e. the
886 first non-alphameric character after $header_xxxxx
887
888 Returns: a pointer to the first character after the header name
889 */
890
891 static uschar *
892 read_header_name(uschar *name, int max, uschar *s)
893 {
894 int prelen = Ustrchr(name, '_') - name + 1;
895 int ptr = Ustrlen(name) - prelen;
896 if (ptr > 0) memmove(name, name+prelen, ptr);
897 while (mac_isgraph(*s) && *s != ':')
898 {
899 if (ptr < max-1) name[ptr++] = *s;
900 s++;
901 }
902 if (*s == ':') s++;
903 name[ptr++] = ':';
904 name[ptr] = 0;
905 return s;
906 }
907
908
909
910 /*************************************************
911 * Pick out a number from a string *
912 *************************************************/
913
914 /* Arguments:
915 n points to an integer into which to put the number
916 s points to the first digit of the number
917
918 Returns: a pointer to the character after the last digit
919 */
920
921 static uschar *
922 read_number(int *n, uschar *s)
923 {
924 *n = 0;
925 while (isdigit(*s)) *n = *n * 10 + (*s++ - '0');
926 return s;
927 }
928
929
930
931 /*************************************************
932 * Extract keyed subfield from a string *
933 *************************************************/
934
935 /* The yield is in dynamic store; NULL means that the key was not found.
936
937 Arguments:
938 key points to the name of the key
939 s points to the string from which to extract the subfield
940
941 Returns: NULL if the subfield was not found, or
942 a pointer to the subfield's data
943 */
944
945 static uschar *
946 expand_getkeyed(uschar *key, uschar *s)
947 {
948 int length = Ustrlen(key);
949 while (isspace(*s)) s++;
950
951 /* Loop to search for the key */
952
953 while (*s != 0)
954 {
955 int dkeylength;
956 uschar *data;
957 uschar *dkey = s;
958
959 while (*s != 0 && *s != '=' && !isspace(*s)) s++;
960 dkeylength = s - dkey;
961 while (isspace(*s)) s++;
962 if (*s == '=') while (isspace((*(++s))));
963
964 data = string_dequote(&s);
965 if (length == dkeylength && strncmpic(key, dkey, length) == 0)
966 return data;
967
968 while (isspace(*s)) s++;
969 }
970
971 return NULL;
972 }
973
974
975
976
977 /*************************************************
978 * Extract numbered subfield from string *
979 *************************************************/
980
981 /* Extracts a numbered field from a string that is divided by tokens - for
982 example a line from /etc/passwd is divided by colon characters. First field is
983 numbered one. Negative arguments count from the right. Zero returns the whole
984 string. Returns NULL if there are insufficient tokens in the string
985
986 ***WARNING***
987 Modifies final argument - this is a dynamically generated string, so that's OK.
988
989 Arguments:
990 field number of field to be extracted,
991 first field = 1, whole string = 0, last field = -1
992 separators characters that are used to break string into tokens
993 s points to the string from which to extract the subfield
994
995 Returns: NULL if the field was not found,
996 a pointer to the field's data inside s (modified to add 0)
997 */
998
999 static uschar *
1000 expand_gettokened (int field, uschar *separators, uschar *s)
1001 {
1002 int sep = 1;
1003 int count;
1004 uschar *ss = s;
1005 uschar *fieldtext = NULL;
1006
1007 if (field == 0) return s;
1008
1009 /* Break the line up into fields in place; for field > 0 we stop when we have
1010 done the number of fields we want. For field < 0 we continue till the end of
1011 the string, counting the number of fields. */
1012
1013 count = (field > 0)? field : INT_MAX;
1014
1015 while (count-- > 0)
1016 {
1017 size_t len;
1018
1019 /* Previous field was the last one in the string. For a positive field
1020 number, this means there are not enough fields. For a negative field number,
1021 check that there are enough, and scan back to find the one that is wanted. */
1022
1023 if (sep == 0)
1024 {
1025 if (field > 0 || (-field) > (INT_MAX - count - 1)) return NULL;
1026 if ((-field) == (INT_MAX - count - 1)) return s;
1027 while (field++ < 0)
1028 {
1029 ss--;
1030 while (ss[-1] != 0) ss--;
1031 }
1032 fieldtext = ss;
1033 break;
1034 }
1035
1036 /* Previous field was not last in the string; save its start and put a
1037 zero at its end. */
1038
1039 fieldtext = ss;
1040 len = Ustrcspn(ss, separators);
1041 sep = ss[len];
1042 ss[len] = 0;
1043 ss += len + 1;
1044 }
1045
1046 return fieldtext;
1047 }
1048
1049
1050
1051 /*************************************************
1052 * Extract a substring from a string *
1053 *************************************************/
1054
1055 /* Perform the ${substr or ${length expansion operations.
1056
1057 Arguments:
1058 subject the input string
1059 value1 the offset from the start of the input string to the start of
1060 the output string; if negative, count from the right.
1061 value2 the length of the output string, or negative (-1) for unset
1062 if value1 is positive, unset means "all after"
1063 if value1 is negative, unset means "all before"
1064 len set to the length of the returned string
1065
1066 Returns: pointer to the output string, or NULL if there is an error
1067 */
1068
1069 static uschar *
1070 extract_substr(uschar *subject, int value1, int value2, int *len)
1071 {
1072 int sublen = Ustrlen(subject);
1073
1074 if (value1 < 0) /* count from right */
1075 {
1076 value1 += sublen;
1077
1078 /* If the position is before the start, skip to the start, and adjust the
1079 length. If the length ends up negative, the substring is null because nothing
1080 can precede. This falls out naturally when the length is unset, meaning "all
1081 to the left". */
1082
1083 if (value1 < 0)
1084 {
1085 value2 += value1;
1086 if (value2 < 0) value2 = 0;
1087 value1 = 0;
1088 }
1089
1090 /* Otherwise an unset length => characters before value1 */
1091
1092 else if (value2 < 0)
1093 {
1094 value2 = value1;
1095 value1 = 0;
1096 }
1097 }
1098
1099 /* For a non-negative offset, if the starting position is past the end of the
1100 string, the result will be the null string. Otherwise, an unset length means
1101 "rest"; just set it to the maximum - it will be cut down below if necessary. */
1102
1103 else
1104 {
1105 if (value1 > sublen)
1106 {
1107 value1 = sublen;
1108 value2 = 0;
1109 }
1110 else if (value2 < 0) value2 = sublen;
1111 }
1112
1113 /* Cut the length down to the maximum possible for the offset value, and get
1114 the required characters. */
1115
1116 if (value1 + value2 > sublen) value2 = sublen - value1;
1117 *len = value2;
1118 return subject + value1;
1119 }
1120
1121
1122
1123
1124 /*************************************************
1125 * Old-style hash of a string *
1126 *************************************************/
1127
1128 /* Perform the ${hash expansion operation.
1129
1130 Arguments:
1131 subject the input string (an expanded substring)
1132 value1 the length of the output string; if greater or equal to the
1133 length of the input string, the input string is returned
1134 value2 the number of hash characters to use, or 26 if negative
1135 len set to the length of the returned string
1136
1137 Returns: pointer to the output string, or NULL if there is an error
1138 */
1139
1140 static uschar *
1141 compute_hash(uschar *subject, int value1, int value2, int *len)
1142 {
1143 int sublen = Ustrlen(subject);
1144
1145 if (value2 < 0) value2 = 26;
1146 else if (value2 > Ustrlen(hashcodes))
1147 {
1148 expand_string_message =
1149 string_sprintf("hash count \"%d\" too big", value2);
1150 return NULL;
1151 }
1152
1153 /* Calculate the hash text. We know it is shorter than the original string, so
1154 can safely place it in subject[] (we know that subject is always itself an
1155 expanded substring). */
1156
1157 if (value1 < sublen)
1158 {
1159 int c;
1160 int i = 0;
1161 int j = value1;
1162 while ((c = (subject[j])) != 0)
1163 {
1164 int shift = (c + j++) & 7;
1165 subject[i] ^= (c << shift) | (c >> (8-shift));
1166 if (++i >= value1) i = 0;
1167 }
1168 for (i = 0; i < value1; i++)
1169 subject[i] = hashcodes[(subject[i]) % value2];
1170 }
1171 else value1 = sublen;
1172
1173 *len = value1;
1174 return subject;
1175 }
1176
1177
1178
1179
1180 /*************************************************
1181 * Numeric hash of a string *
1182 *************************************************/
1183
1184 /* Perform the ${nhash expansion operation. The first characters of the
1185 string are treated as most important, and get the highest prime numbers.
1186
1187 Arguments:
1188 subject the input string
1189 value1 the maximum value of the first part of the result
1190 value2 the maximum value of the second part of the result,
1191 or negative to produce only a one-part result
1192 len set to the length of the returned string
1193
1194 Returns: pointer to the output string, or NULL if there is an error.
1195 */
1196
1197 static uschar *
1198 compute_nhash (uschar *subject, int value1, int value2, int *len)
1199 {
1200 uschar *s = subject;
1201 int i = 0;
1202 unsigned long int total = 0; /* no overflow */
1203
1204 while (*s != 0)
1205 {
1206 if (i == 0) i = sizeof(prime)/sizeof(int) - 1;
1207 total += prime[i--] * (unsigned int)(*s++);
1208 }
1209
1210 /* If value2 is unset, just compute one number */
1211
1212 if (value2 < 0)
1213 {
1214 s = string_sprintf("%d", total % value1);
1215 }
1216
1217 /* Otherwise do a div/mod hash */
1218
1219 else
1220 {
1221 total = total % (value1 * value2);
1222 s = string_sprintf("%d/%d", total/value2, total % value2);
1223 }
1224
1225 *len = Ustrlen(s);
1226 return s;
1227 }
1228
1229
1230
1231
1232
1233 /*************************************************
1234 * Find the value of a header or headers *
1235 *************************************************/
1236
1237 /* Multiple instances of the same header get concatenated, and this function
1238 can also return a concatenation of all the header lines. When concatenating
1239 specific headers that contain lists of addresses, a comma is inserted between
1240 them. Otherwise we use a straight concatenation. Because some messages can have
1241 pathologically large number of lines, there is a limit on the length that is
1242 returned. Also, to avoid massive store use which would result from using
1243 string_cat() as it copies and extends strings, we do a preliminary pass to find
1244 out exactly how much store will be needed. On "normal" messages this will be
1245 pretty trivial.
1246
1247 Arguments:
1248 name the name of the header, without the leading $header_ or $h_,
1249 or NULL if a concatenation of all headers is required
1250 exists_only TRUE if called from a def: test; don't need to build a string;
1251 just return a string that is not "" and not "0" if the header
1252 exists
1253 newsize return the size of memory block that was obtained; may be NULL
1254 if exists_only is TRUE
1255 want_raw TRUE if called for $rh_ or $rheader_ variables; no processing,
1256 other than concatenating, will be done on the header. Also used
1257 for $message_headers_raw.
1258 charset name of charset to translate MIME words to; used only if
1259 want_raw is false; if NULL, no translation is done (this is
1260 used for $bh_ and $bheader_)
1261
1262 Returns: NULL if the header does not exist, else a pointer to a new
1263 store block
1264 */
1265
1266 static uschar *
1267 find_header(uschar *name, BOOL exists_only, int *newsize, BOOL want_raw,
1268 uschar *charset)
1269 {
1270 BOOL found = name == NULL;
1271 int comma = 0;
1272 int len = found? 0 : Ustrlen(name);
1273 int i;
1274 uschar *yield = NULL;
1275 uschar *ptr = NULL;
1276
1277 /* Loop for two passes - saves code repetition */
1278
1279 for (i = 0; i < 2; i++)
1280 {
1281 int size = 0;
1282 header_line *h;
1283
1284 for (h = header_list; size < header_insert_maxlen && h != NULL; h = h->next)
1285 {
1286 if (h->type != htype_old && h->text != NULL) /* NULL => Received: placeholder */
1287 {
1288 if (name == NULL || (len <= h->slen && strncmpic(name, h->text, len) == 0))
1289 {
1290 int ilen;
1291 uschar *t;
1292
1293 if (exists_only) return US"1"; /* don't need actual string */
1294 found = TRUE;
1295 t = h->text + len; /* text to insert */
1296 if (!want_raw) /* unless wanted raw, */
1297 while (isspace(*t)) t++; /* remove leading white space */
1298 ilen = h->slen - (t - h->text); /* length to insert */
1299
1300 /* Unless wanted raw, remove trailing whitespace, including the
1301 newline. */
1302
1303 if (!want_raw)
1304 while (ilen > 0 && isspace(t[ilen-1])) ilen--;
1305
1306 /* Set comma = 1 if handling a single header and it's one of those
1307 that contains an address list, except when asked for raw headers. Only
1308 need to do this once. */
1309
1310 if (!want_raw && name != NULL && comma == 0 &&
1311 Ustrchr("BCFRST", h->type) != NULL)
1312 comma = 1;
1313
1314 /* First pass - compute total store needed; second pass - compute
1315 total store used, including this header. */
1316
1317 size += ilen + comma + 1; /* +1 for the newline */
1318
1319 /* Second pass - concatentate the data, up to a maximum. Note that
1320 the loop stops when size hits the limit. */
1321
1322 if (i != 0)
1323 {
1324 if (size > header_insert_maxlen)
1325 {
1326 ilen -= size - header_insert_maxlen - 1;
1327 comma = 0;
1328 }
1329 Ustrncpy(ptr, t, ilen);
1330 ptr += ilen;
1331
1332 /* For a non-raw header, put in the comma if needed, then add
1333 back the newline we removed above, provided there was some text in
1334 the header. */
1335
1336 if (!want_raw && ilen > 0)
1337 {
1338 if (comma != 0) *ptr++ = ',';
1339 *ptr++ = '\n';
1340 }
1341 }
1342 }
1343 }
1344 }
1345
1346 /* At end of first pass, return NULL if no header found. Then truncate size
1347 if necessary, and get the buffer to hold the data, returning the buffer size.
1348 */
1349
1350 if (i == 0)
1351 {
1352 if (!found) return NULL;
1353 if (size > header_insert_maxlen) size = header_insert_maxlen;
1354 *newsize = size + 1;
1355 ptr = yield = store_get(*newsize);
1356 }
1357 }
1358
1359 /* That's all we do for raw header expansion. */
1360
1361 if (want_raw)
1362 {
1363 *ptr = 0;
1364 }
1365
1366 /* Otherwise, remove a final newline and a redundant added comma. Then we do
1367 RFC 2047 decoding, translating the charset if requested. The rfc2047_decode2()
1368 function can return an error with decoded data if the charset translation
1369 fails. If decoding fails, it returns NULL. */
1370
1371 else
1372 {
1373 uschar *decoded, *error;
1374 if (ptr > yield && ptr[-1] == '\n') ptr--;
1375 if (ptr > yield && comma != 0 && ptr[-1] == ',') ptr--;
1376 *ptr = 0;
1377 decoded = rfc2047_decode2(yield, check_rfc2047_length, charset, '?', NULL,
1378 newsize, &error);
1379 if (error != NULL)
1380 {
1381 DEBUG(D_any) debug_printf("*** error in RFC 2047 decoding: %s\n"
1382 " input was: %s\n", error, yield);
1383 }
1384 if (decoded != NULL) yield = decoded;
1385 }
1386
1387 return yield;
1388 }
1389
1390
1391
1392
1393 /*************************************************
1394 * Find value of a variable *
1395 *************************************************/
1396
1397 /* The table of variables is kept in alphabetic order, so we can search it
1398 using a binary chop. The "choplen" variable is nothing to do with the binary
1399 chop.
1400
1401 Arguments:
1402 name the name of the variable being sought
1403 exists_only TRUE if this is a def: test; passed on to find_header()
1404 skipping TRUE => skip any processing evaluation; this is not the same as
1405 exists_only because def: may test for values that are first
1406 evaluated here
1407 newsize pointer to an int which is initially zero; if the answer is in
1408 a new memory buffer, *newsize is set to its size
1409
1410 Returns: NULL if the variable does not exist, or
1411 a pointer to the variable's contents, or
1412 something non-NULL if exists_only is TRUE
1413 */
1414
1415 static uschar *
1416 find_variable(uschar *name, BOOL exists_only, BOOL skipping, int *newsize)
1417 {
1418 int first = 0;
1419 int last = var_table_size;
1420
1421 /* Handle ACL variables, whose names are of the form acl_cxxx or acl_mxxx.
1422 Originally, xxx had to be a number in the range 0-9 (later 0-19), but from
1423 release 4.64 onwards arbitrary names are permitted, as long as the first 5
1424 characters are acl_c or acl_m and the sixth is either a digit or an underscore
1425 (this gave backwards compatibility at the changeover). There may be built-in
1426 variables whose names start acl_ but they should never start in this way. This
1427 slightly messy specification is a consequence of the history, needless to say.
1428
1429 If an ACL variable does not exist, treat it as empty, unless strict_acl_vars is
1430 set, in which case give an error. */
1431
1432 if ((Ustrncmp(name, "acl_c", 5) == 0 || Ustrncmp(name, "acl_m", 5) == 0) &&
1433 !isalpha(name[5]))
1434 {
1435 tree_node *node =
1436 tree_search((name[4] == 'c')? acl_var_c : acl_var_m, name + 4);
1437 return (node == NULL)? (strict_acl_vars? NULL : US"") : node->data.ptr;
1438 }
1439
1440 /* Handle $auth<n> variables. */
1441
1442 if (Ustrncmp(name, "auth", 4) == 0)
1443 {
1444 uschar *endptr;
1445 int n = Ustrtoul(name + 4, &endptr, 10);
1446 if (*endptr == 0 && n != 0 && n <= AUTH_VARS)
1447 return (auth_vars[n-1] == NULL)? US"" : auth_vars[n-1];
1448 }
1449
1450 /* For all other variables, search the table */
1451
1452 while (last > first)
1453 {
1454 uschar *s, *domain;
1455 uschar **ss;
1456 int middle = (first + last)/2;
1457 int c = Ustrcmp(name, var_table[middle].name);
1458
1459 if (c > 0) { first = middle + 1; continue; }
1460 if (c < 0) { last = middle; continue; }
1461
1462 /* Found an existing variable. If in skipping state, the value isn't needed,
1463 and we want to avoid processing (such as looking up the host name). */
1464
1465 if (skipping) return US"";
1466
1467 switch (var_table[middle].type)
1468 {
1469 case vtype_filter_int:
1470 if (!filter_running) return NULL;
1471 /* Fall through */
1472 /* VVVVVVVVVVVV */
1473 case vtype_int:
1474 sprintf(CS var_buffer, "%d", *(int *)(var_table[middle].value)); /* Integer */
1475 return var_buffer;
1476
1477 case vtype_ino:
1478 sprintf(CS var_buffer, "%ld", (long int)(*(ino_t *)(var_table[middle].value))); /* Inode */
1479 return var_buffer;
1480
1481 case vtype_gid:
1482 sprintf(CS var_buffer, "%ld", (long int)(*(gid_t *)(var_table[middle].value))); /* gid */
1483 return var_buffer;
1484
1485 case vtype_uid:
1486 sprintf(CS var_buffer, "%ld", (long int)(*(uid_t *)(var_table[middle].value))); /* uid */
1487 return var_buffer;
1488
1489 case vtype_stringptr: /* Pointer to string */
1490 s = *((uschar **)(var_table[middle].value));
1491 return (s == NULL)? US"" : s;
1492
1493 case vtype_pid:
1494 sprintf(CS var_buffer, "%d", (int)getpid()); /* pid */
1495 return var_buffer;
1496
1497 case vtype_load_avg:
1498 sprintf(CS var_buffer, "%d", OS_GETLOADAVG()); /* load_average */
1499 return var_buffer;
1500
1501 case vtype_host_lookup: /* Lookup if not done so */
1502 if (sender_host_name == NULL && sender_host_address != NULL &&
1503 !host_lookup_failed && host_name_lookup() == OK)
1504 host_build_sender_fullhost();
1505 return (sender_host_name == NULL)? US"" : sender_host_name;
1506
1507 case vtype_localpart: /* Get local part from address */
1508 s = *((uschar **)(var_table[middle].value));
1509 if (s == NULL) return US"";
1510 domain = Ustrrchr(s, '@');
1511 if (domain == NULL) return s;
1512 if (domain - s > sizeof(var_buffer) - 1)
1513 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "local part longer than %d in "
1514 "string expansion", sizeof(var_buffer));
1515 Ustrncpy(var_buffer, s, domain - s);
1516 var_buffer[domain - s] = 0;
1517 return var_buffer;
1518
1519 case vtype_domain: /* Get domain from address */
1520 s = *((uschar **)(var_table[middle].value));
1521 if (s == NULL) return US"";
1522 domain = Ustrrchr(s, '@');
1523 return (domain == NULL)? US"" : domain + 1;
1524
1525 case vtype_msgheaders:
1526 return find_header(NULL, exists_only, newsize, FALSE, NULL);
1527
1528 case vtype_msgheaders_raw:
1529 return find_header(NULL, exists_only, newsize, TRUE, NULL);
1530
1531 case vtype_msgbody: /* Pointer to msgbody string */
1532 case vtype_msgbody_end: /* Ditto, the end of the msg */
1533 ss = (uschar **)(var_table[middle].value);
1534 if (*ss == NULL && deliver_datafile >= 0) /* Read body when needed */
1535 {
1536 uschar *body;
1537 off_t start_offset = SPOOL_DATA_START_OFFSET;
1538 int len = message_body_visible;
1539 if (len > message_size) len = message_size;
1540 *ss = body = store_malloc(len+1);
1541 body[0] = 0;
1542 if (var_table[middle].type == vtype_msgbody_end)
1543 {
1544 struct stat statbuf;
1545 if (fstat(deliver_datafile, &statbuf) == 0)
1546 {
1547 start_offset = statbuf.st_size - len;
1548 if (start_offset < SPOOL_DATA_START_OFFSET)
1549 start_offset = SPOOL_DATA_START_OFFSET;
1550 }
1551 }
1552 lseek(deliver_datafile, start_offset, SEEK_SET);
1553 len = read(deliver_datafile, body, len);
1554 if (len > 0)
1555 {
1556 body[len] = 0;
1557 if (message_body_newlines) /* Separate loops for efficiency */
1558 {
1559 while (len > 0)
1560 { if (body[--len] == 0) body[len] = ' '; }
1561 }
1562 else
1563 {
1564 while (len > 0)
1565 { if (body[--len] == '\n' || body[len] == 0) body[len] = ' '; }
1566 }
1567 }
1568 }
1569 return (*ss == NULL)? US"" : *ss;
1570
1571 case vtype_todbsdin: /* BSD inbox time of day */
1572 return tod_stamp(tod_bsdin);
1573
1574 case vtype_tode: /* Unix epoch time of day */
1575 return tod_stamp(tod_epoch);
1576
1577 case vtype_todf: /* Full time of day */
1578 return tod_stamp(tod_full);
1579
1580 case vtype_todl: /* Log format time of day */
1581 return tod_stamp(tod_log_bare); /* (without timezone) */
1582
1583 case vtype_todzone: /* Time zone offset only */
1584 return tod_stamp(tod_zone);
1585
1586 case vtype_todzulu: /* Zulu time */
1587 return tod_stamp(tod_zulu);
1588
1589 case vtype_todlf: /* Log file datestamp tod */
1590 return tod_stamp(tod_log_datestamp_daily);
1591
1592 case vtype_reply: /* Get reply address */
1593 s = find_header(US"reply-to:", exists_only, newsize, TRUE,
1594 headers_charset);
1595 if (s != NULL) while (isspace(*s)) s++;
1596 if (s == NULL || *s == 0)
1597 {
1598 *newsize = 0; /* For the *s==0 case */
1599 s = find_header(US"from:", exists_only, newsize, TRUE, headers_charset);
1600 }
1601 if (s != NULL)
1602 {
1603 uschar *t;
1604 while (isspace(*s)) s++;
1605 for (t = s; *t != 0; t++) if (*t == '\n') *t = ' ';
1606 while (t > s && isspace(t[-1])) t--;
1607 *t = 0;
1608 }
1609 return (s == NULL)? US"" : s;
1610
1611 /* A recipients list is available only during system message filtering,
1612 during ACL processing after DATA, and while expanding pipe commands
1613 generated from a system filter, but not elsewhere. */
1614
1615 case vtype_recipients:
1616 if (!enable_dollar_recipients) return NULL; else
1617 {
1618 int size = 128;
1619 int ptr = 0;
1620 int i;
1621 s = store_get(size);
1622 for (i = 0; i < recipients_count; i++)
1623 {
1624 if (i != 0) s = string_cat(s, &size, &ptr, US", ", 2);
1625 s = string_cat(s, &size, &ptr, recipients_list[i].address,
1626 Ustrlen(recipients_list[i].address));
1627 }
1628 s[ptr] = 0; /* string_cat() leaves room */
1629 }
1630 return s;
1631
1632 case vtype_pspace:
1633 {
1634 int inodes;
1635 sprintf(CS var_buffer, "%d",
1636 receive_statvfs(var_table[middle].value == (void *)TRUE, &inodes));
1637 }
1638 return var_buffer;
1639
1640 case vtype_pinodes:
1641 {
1642 int inodes;
1643 (void) receive_statvfs(var_table[middle].value == (void *)TRUE, &inodes);
1644 sprintf(CS var_buffer, "%d", inodes);
1645 }
1646 return var_buffer;
1647
1648 #ifndef DISABLE_DKIM
1649 case vtype_dkim:
1650 return dkim_exim_expand_query((int)(long)var_table[middle].value);
1651 #endif
1652
1653 }
1654 }
1655
1656 return NULL; /* Unknown variable name */
1657 }
1658
1659
1660
1661
1662 /*************************************************
1663 * Read and expand substrings *
1664 *************************************************/
1665
1666 /* This function is called to read and expand argument substrings for various
1667 expansion items. Some have a minimum requirement that is less than the maximum;
1668 in these cases, the first non-present one is set to NULL.
1669
1670 Arguments:
1671 sub points to vector of pointers to set
1672 n maximum number of substrings
1673 m minimum required
1674 sptr points to current string pointer
1675 skipping the skipping flag
1676 check_end if TRUE, check for final '}'
1677 name name of item, for error message
1678
1679 Returns: 0 OK; string pointer updated
1680 1 curly bracketing error (too few arguments)
1681 2 too many arguments (only if check_end is set); message set
1682 3 other error (expansion failure)
1683 */
1684
1685 static int
1686 read_subs(uschar **sub, int n, int m, uschar **sptr, BOOL skipping,
1687 BOOL check_end, uschar *name)
1688 {
1689 int i;
1690 uschar *s = *sptr;
1691
1692 while (isspace(*s)) s++;
1693 for (i = 0; i < n; i++)
1694 {
1695 if (*s != '{')
1696 {
1697 if (i < m) return 1;
1698 sub[i] = NULL;
1699 break;
1700 }
1701 sub[i] = expand_string_internal(s+1, TRUE, &s, skipping);
1702 if (sub[i] == NULL) return 3;
1703 if (*s++ != '}') return 1;
1704 while (isspace(*s)) s++;
1705 }
1706 if (check_end && *s++ != '}')
1707 {
1708 if (s[-1] == '{')
1709 {
1710 expand_string_message = string_sprintf("Too many arguments for \"%s\" "
1711 "(max is %d)", name, n);
1712 return 2;
1713 }
1714 return 1;
1715 }
1716
1717 *sptr = s;
1718 return 0;
1719 }
1720
1721
1722
1723
1724 /*************************************************
1725 * Elaborate message for bad variable *
1726 *************************************************/
1727
1728 /* For the "unknown variable" message, take a look at the variable's name, and
1729 give additional information about possible ACL variables. The extra information
1730 is added on to expand_string_message.
1731
1732 Argument: the name of the variable
1733 Returns: nothing
1734 */
1735
1736 static void
1737 check_variable_error_message(uschar *name)
1738 {
1739 if (Ustrncmp(name, "acl_", 4) == 0)
1740 expand_string_message = string_sprintf("%s (%s)", expand_string_message,
1741 (name[4] == 'c' || name[4] == 'm')?
1742 (isalpha(name[5])?
1743 US"6th character of a user-defined ACL variable must be a digit or underscore" :
1744 US"strict_acl_vars is set" /* Syntax is OK, it has to be this */
1745 ) :
1746 US"user-defined ACL variables must start acl_c or acl_m");
1747 }
1748
1749
1750
1751 /*************************************************
1752 * Read and evaluate a condition *
1753 *************************************************/
1754
1755 /*
1756 Arguments:
1757 s points to the start of the condition text
1758 yield points to a BOOL to hold the result of the condition test;
1759 if NULL, we are just reading through a condition that is
1760 part of an "or" combination to check syntax, or in a state
1761 where the answer isn't required
1762
1763 Returns: a pointer to the first character after the condition, or
1764 NULL after an error
1765 */
1766
1767 static uschar *
1768 eval_condition(uschar *s, BOOL *yield)
1769 {
1770 BOOL testfor = TRUE;
1771 BOOL tempcond, combined_cond;
1772 BOOL *subcondptr;
1773 int i, rc, cond_type, roffset;
1774 int num[2];
1775 struct stat statbuf;
1776 uschar name[256];
1777 uschar *sub[4];
1778
1779 const pcre *re;
1780 const uschar *rerror;
1781
1782 for (;;)
1783 {
1784 while (isspace(*s)) s++;
1785 if (*s == '!') { testfor = !testfor; s++; } else break;
1786 }
1787
1788 /* Numeric comparisons are symbolic */
1789
1790 if (*s == '=' || *s == '>' || *s == '<')
1791 {
1792 int p = 0;
1793 name[p++] = *s++;
1794 if (*s == '=')
1795 {
1796 name[p++] = '=';
1797 s++;
1798 }
1799 name[p] = 0;
1800 }
1801
1802 /* All other conditions are named */
1803
1804 else s = read_name(name, 256, s, US"_");
1805
1806 /* If we haven't read a name, it means some non-alpha character is first. */
1807
1808 if (name[0] == 0)
1809 {
1810 expand_string_message = string_sprintf("condition name expected, "
1811 "but found \"%.16s\"", s);
1812 return NULL;
1813 }
1814
1815 /* Find which condition we are dealing with, and switch on it */
1816
1817 cond_type = chop_match(name, cond_table, sizeof(cond_table)/sizeof(uschar *));
1818 switch(cond_type)
1819 {
1820 /* def: tests for a non-empty variable, or for the existence of a header. If
1821 yield == NULL we are in a skipping state, and don't care about the answer. */
1822
1823 case ECOND_DEF:
1824 if (*s != ':')
1825 {
1826 expand_string_message = US"\":\" expected after \"def\"";
1827 return NULL;
1828 }
1829
1830 s = read_name(name, 256, s+1, US"_");
1831
1832 /* Test for a header's existence. If the name contains a closing brace
1833 character, this may be a user error where the terminating colon has been
1834 omitted. Set a flag to adjust a subsequent error message in this case. */
1835
1836 if (Ustrncmp(name, "h_", 2) == 0 ||
1837 Ustrncmp(name, "rh_", 3) == 0 ||
1838 Ustrncmp(name, "bh_", 3) == 0 ||
1839 Ustrncmp(name, "header_", 7) == 0 ||
1840 Ustrncmp(name, "rheader_", 8) == 0 ||
1841 Ustrncmp(name, "bheader_", 8) == 0)
1842 {
1843 s = read_header_name(name, 256, s);
1844 if (Ustrchr(name, '}') != NULL) malformed_header = TRUE;
1845 if (yield != NULL) *yield =
1846 (find_header(name, TRUE, NULL, FALSE, NULL) != NULL) == testfor;
1847 }
1848
1849 /* Test for a variable's having a non-empty value. A non-existent variable
1850 causes an expansion failure. */
1851
1852 else
1853 {
1854 uschar *value = find_variable(name, TRUE, yield == NULL, NULL);
1855 if (value == NULL)
1856 {
1857 expand_string_message = (name[0] == 0)?
1858 string_sprintf("variable name omitted after \"def:\"") :
1859 string_sprintf("unknown variable \"%s\" after \"def:\"", name);
1860 check_variable_error_message(name);
1861 return NULL;
1862 }
1863 if (yield != NULL) *yield = (value[0] != 0) == testfor;
1864 }
1865
1866 return s;
1867
1868
1869 /* first_delivery tests for first delivery attempt */
1870
1871 case ECOND_FIRST_DELIVERY:
1872 if (yield != NULL) *yield = deliver_firsttime == testfor;
1873 return s;
1874
1875
1876 /* queue_running tests for any process started by a queue runner */
1877
1878 case ECOND_QUEUE_RUNNING:
1879 if (yield != NULL) *yield = (queue_run_pid != (pid_t)0) == testfor;
1880 return s;
1881
1882
1883 /* exists: tests for file existence
1884 isip: tests for any IP address
1885 isip4: tests for an IPv4 address
1886 isip6: tests for an IPv6 address
1887 pam: does PAM authentication
1888 radius: does RADIUS authentication
1889 ldapauth: does LDAP authentication
1890 pwcheck: does Cyrus SASL pwcheck authentication
1891 */
1892
1893 case ECOND_EXISTS:
1894 case ECOND_ISIP:
1895 case ECOND_ISIP4:
1896 case ECOND_ISIP6:
1897 case ECOND_PAM:
1898 case ECOND_RADIUS:
1899 case ECOND_LDAPAUTH:
1900 case ECOND_PWCHECK:
1901
1902 while (isspace(*s)) s++;
1903 if (*s != '{') goto COND_FAILED_CURLY_START;
1904
1905 sub[0] = expand_string_internal(s+1, TRUE, &s, yield == NULL);
1906 if (sub[0] == NULL) return NULL;
1907 if (*s++ != '}') goto COND_FAILED_CURLY_END;
1908
1909 if (yield == NULL) return s; /* No need to run the test if skipping */
1910
1911 switch(cond_type)
1912 {
1913 case ECOND_EXISTS:
1914 if ((expand_forbid & RDO_EXISTS) != 0)
1915 {
1916 expand_string_message = US"File existence tests are not permitted";
1917 return NULL;
1918 }
1919 *yield = (Ustat(sub[0], &statbuf) == 0) == testfor;
1920 break;
1921
1922 case ECOND_ISIP:
1923 case ECOND_ISIP4:
1924 case ECOND_ISIP6:
1925 rc = string_is_ip_address(sub[0], NULL);
1926 *yield = ((cond_type == ECOND_ISIP)? (rc != 0) :
1927 (cond_type == ECOND_ISIP4)? (rc == 4) : (rc == 6)) == testfor;
1928 break;
1929
1930 /* Various authentication tests - all optionally compiled */
1931
1932 case ECOND_PAM:
1933 #ifdef SUPPORT_PAM
1934 rc = auth_call_pam(sub[0], &expand_string_message);
1935 goto END_AUTH;
1936 #else
1937 goto COND_FAILED_NOT_COMPILED;
1938 #endif /* SUPPORT_PAM */
1939
1940 case ECOND_RADIUS:
1941 #ifdef RADIUS_CONFIG_FILE
1942 rc = auth_call_radius(sub[0], &expand_string_message);
1943 goto END_AUTH;
1944 #else
1945 goto COND_FAILED_NOT_COMPILED;
1946 #endif /* RADIUS_CONFIG_FILE */
1947
1948 case ECOND_LDAPAUTH:
1949 #ifdef LOOKUP_LDAP
1950 {
1951 /* Just to keep the interface the same */
1952 BOOL do_cache;
1953 int old_pool = store_pool;
1954 store_pool = POOL_SEARCH;
1955 rc = eldapauth_find((void *)(-1), NULL, sub[0], Ustrlen(sub[0]), NULL,
1956 &expand_string_message, &do_cache);
1957 store_pool = old_pool;
1958 }
1959 goto END_AUTH;
1960 #else
1961 goto COND_FAILED_NOT_COMPILED;
1962 #endif /* LOOKUP_LDAP */
1963
1964 case ECOND_PWCHECK:
1965 #ifdef CYRUS_PWCHECK_SOCKET
1966 rc = auth_call_pwcheck(sub[0], &expand_string_message);
1967 goto END_AUTH;
1968 #else
1969 goto COND_FAILED_NOT_COMPILED;
1970 #endif /* CYRUS_PWCHECK_SOCKET */
1971
1972 #if defined(SUPPORT_PAM) || defined(RADIUS_CONFIG_FILE) || \
1973 defined(LOOKUP_LDAP) || defined(CYRUS_PWCHECK_SOCKET)
1974 END_AUTH:
1975 if (rc == ERROR || rc == DEFER) return NULL;
1976 *yield = (rc == OK) == testfor;
1977 #endif
1978 }
1979 return s;
1980
1981
1982 /* saslauthd: does Cyrus saslauthd authentication. Four parameters are used:
1983
1984 ${if saslauthd {{username}{password}{service}{realm}} {yes}[no}}
1985
1986 However, the last two are optional. That is why the whole set is enclosed
1987 in their own set or braces. */
1988
1989 case ECOND_SASLAUTHD:
1990 #ifndef CYRUS_SASLAUTHD_SOCKET
1991 goto COND_FAILED_NOT_COMPILED;
1992 #else
1993 while (isspace(*s)) s++;
1994 if (*s++ != '{') goto COND_FAILED_CURLY_START;
1995 switch(read_subs(sub, 4, 2, &s, yield == NULL, TRUE, US"saslauthd"))
1996 {
1997 case 1: expand_string_message = US"too few arguments or bracketing "
1998 "error for saslauthd";
1999 case 2:
2000 case 3: return NULL;
2001 }
2002 if (sub[2] == NULL) sub[3] = NULL; /* realm if no service */
2003 if (yield != NULL)
2004 {
2005 int rc;
2006 rc = auth_call_saslauthd(sub[0], sub[1], sub[2], sub[3],
2007 &expand_string_message);
2008 if (rc == ERROR || rc == DEFER) return NULL;
2009 *yield = (rc == OK) == testfor;
2010 }
2011 return s;
2012 #endif /* CYRUS_SASLAUTHD_SOCKET */
2013
2014
2015 /* symbolic operators for numeric and string comparison, and a number of
2016 other operators, all requiring two arguments.
2017
2018 match: does a regular expression match and sets up the numerical
2019 variables if it succeeds
2020 match_address: matches in an address list
2021 match_domain: matches in a domain list
2022 match_ip: matches a host list that is restricted to IP addresses
2023 match_local_part: matches in a local part list
2024 crypteq: encrypts plaintext and compares against an encrypted text,
2025 using crypt(), crypt16(), MD5 or SHA-1
2026 */
2027
2028 case ECOND_MATCH:
2029 case ECOND_MATCH_ADDRESS:
2030 case ECOND_MATCH_DOMAIN:
2031 case ECOND_MATCH_IP:
2032 case ECOND_MATCH_LOCAL_PART:
2033 case ECOND_CRYPTEQ:
2034
2035 case ECOND_NUM_L: /* Numerical comparisons */
2036 case ECOND_NUM_LE:
2037 case ECOND_NUM_E:
2038 case ECOND_NUM_EE:
2039 case ECOND_NUM_G:
2040 case ECOND_NUM_GE:
2041
2042 case ECOND_STR_LT: /* String comparisons */
2043 case ECOND_STR_LTI:
2044 case ECOND_STR_LE:
2045 case ECOND_STR_LEI:
2046 case ECOND_STR_EQ:
2047 case ECOND_STR_EQI:
2048 case ECOND_STR_GT:
2049 case ECOND_STR_GTI:
2050 case ECOND_STR_GE:
2051 case ECOND_STR_GEI:
2052
2053 for (i = 0; i < 2; i++)
2054 {
2055 while (isspace(*s)) s++;
2056 if (*s != '{')
2057 {
2058 if (i == 0) goto COND_FAILED_CURLY_START;
2059 expand_string_message = string_sprintf("missing 2nd string in {} "
2060 "after \"%s\"", name);
2061 return NULL;
2062 }
2063 sub[i] = expand_string_internal(s+1, TRUE, &s, yield == NULL);
2064 if (sub[i] == NULL) return NULL;
2065 if (*s++ != '}') goto COND_FAILED_CURLY_END;
2066
2067 /* Convert to numerical if required; we know that the names of all the
2068 conditions that compare numbers do not start with a letter. This just saves
2069 checking for them individually. */
2070
2071 if (!isalpha(name[0]) && yield != NULL)
2072 {
2073 if (sub[i][0] == 0)
2074 {
2075 num[i] = 0;
2076 DEBUG(D_expand)
2077 debug_printf("empty string cast to zero for numerical comparison\n");
2078 }
2079 else
2080 {
2081 num[i] = expand_string_integer(sub[i], FALSE);
2082 if (expand_string_message != NULL) return NULL;
2083 }
2084 }
2085 }
2086
2087 /* Result not required */
2088
2089 if (yield == NULL) return s;
2090
2091 /* Do an appropriate comparison */
2092
2093 switch(cond_type)
2094 {
2095 case ECOND_NUM_E:
2096 case ECOND_NUM_EE:
2097 *yield = (num[0] == num[1]) == testfor;
2098 break;
2099
2100 case ECOND_NUM_G:
2101 *yield = (num[0] > num[1]) == testfor;
2102 break;
2103
2104 case ECOND_NUM_GE:
2105 *yield = (num[0] >= num[1]) == testfor;
2106 break;
2107
2108 case ECOND_NUM_L:
2109 *yield = (num[0] < num[1]) == testfor;
2110 break;
2111
2112 case ECOND_NUM_LE:
2113 *yield = (num[0] <= num[1]) == testfor;
2114 break;
2115
2116 case ECOND_STR_LT:
2117 *yield = (Ustrcmp(sub[0], sub[1]) < 0) == testfor;
2118 break;
2119
2120 case ECOND_STR_LTI:
2121 *yield = (strcmpic(sub[0], sub[1]) < 0) == testfor;
2122 break;
2123
2124 case ECOND_STR_LE:
2125 *yield = (Ustrcmp(sub[0], sub[1]) <= 0) == testfor;
2126 break;
2127
2128 case ECOND_STR_LEI:
2129 *yield = (strcmpic(sub[0], sub[1]) <= 0) == testfor;
2130 break;
2131
2132 case ECOND_STR_EQ:
2133 *yield = (Ustrcmp(sub[0], sub[1]) == 0) == testfor;
2134 break;
2135
2136 case ECOND_STR_EQI:
2137 *yield = (strcmpic(sub[0], sub[1]) == 0) == testfor;
2138 break;
2139
2140 case ECOND_STR_GT:
2141 *yield = (Ustrcmp(sub[0], sub[1]) > 0) == testfor;
2142 break;
2143
2144 case ECOND_STR_GTI:
2145 *yield = (strcmpic(sub[0], sub[1]) > 0) == testfor;
2146 break;
2147
2148 case ECOND_STR_GE:
2149 *yield = (Ustrcmp(sub[0], sub[1]) >= 0) == testfor;
2150 break;
2151
2152 case ECOND_STR_GEI:
2153 *yield = (strcmpic(sub[0], sub[1]) >= 0) == testfor;
2154 break;
2155
2156 case ECOND_MATCH: /* Regular expression match */
2157 re = pcre_compile(CS sub[1], PCRE_COPT, (const char **)&rerror, &roffset,
2158 NULL);
2159 if (re == NULL)
2160 {
2161 expand_string_message = string_sprintf("regular expression error in "
2162 "\"%s\": %s at offset %d", sub[1], rerror, roffset);
2163 return NULL;
2164 }
2165 *yield = regex_match_and_setup(re, sub[0], 0, -1) == testfor;
2166 break;
2167
2168 case ECOND_MATCH_ADDRESS: /* Match in an address list */
2169 rc = match_address_list(sub[0], TRUE, FALSE, &(sub[1]), NULL, -1, 0, NULL);
2170 goto MATCHED_SOMETHING;
2171
2172 case ECOND_MATCH_DOMAIN: /* Match in a domain list */
2173 rc = match_isinlist(sub[0], &(sub[1]), 0, &domainlist_anchor, NULL,
2174 MCL_DOMAIN + MCL_NOEXPAND, TRUE, NULL);
2175 goto MATCHED_SOMETHING;
2176
2177 case ECOND_MATCH_IP: /* Match IP address in a host list */
2178 if (sub[0][0] != 0 && string_is_ip_address(sub[0], NULL) == 0)
2179 {
2180 expand_string_message = string_sprintf("\"%s\" is not an IP address",
2181 sub[0]);
2182 return NULL;
2183 }
2184 else
2185 {
2186 unsigned int *nullcache = NULL;
2187 check_host_block cb;
2188
2189 cb.host_name = US"";
2190 cb.host_address = sub[0];
2191
2192 /* If the host address starts off ::ffff: it is an IPv6 address in
2193 IPv4-compatible mode. Find the IPv4 part for checking against IPv4
2194 addresses. */
2195
2196 cb.host_ipv4 = (Ustrncmp(cb.host_address, "::ffff:", 7) == 0)?
2197 cb.host_address + 7 : cb.host_address;
2198
2199 rc = match_check_list(
2200 &sub[1], /* the list */
2201 0, /* separator character */
2202 &hostlist_anchor, /* anchor pointer */
2203 &nullcache, /* cache pointer */
2204 check_host, /* function for testing */
2205 &cb, /* argument for function */
2206 MCL_HOST, /* type of check */
2207 sub[0], /* text for debugging */
2208 NULL); /* where to pass back data */
2209 }
2210 goto MATCHED_SOMETHING;
2211
2212 case ECOND_MATCH_LOCAL_PART:
2213 rc = match_isinlist(sub[0], &(sub[1]), 0, &localpartlist_anchor, NULL,
2214 MCL_LOCALPART + MCL_NOEXPAND, TRUE, NULL);
2215 /* Fall through */
2216 /* VVVVVVVVVVVV */
2217 MATCHED_SOMETHING:
2218 switch(rc)
2219 {
2220 case OK:
2221 *yield = testfor;
2222 break;
2223
2224 case FAIL:
2225 *yield = !testfor;
2226 break;
2227
2228 case DEFER:
2229 expand_string_message = string_sprintf("unable to complete match "
2230 "against \"%s\": %s", sub[1], search_error_message);
2231 return NULL;
2232 }
2233
2234 break;
2235
2236 /* Various "encrypted" comparisons. If the second string starts with
2237 "{" then an encryption type is given. Default to crypt() or crypt16()
2238 (build-time choice). */
2239
2240 case ECOND_CRYPTEQ:
2241 #ifndef SUPPORT_CRYPTEQ
2242 goto COND_FAILED_NOT_COMPILED;
2243 #else
2244 if (strncmpic(sub[1], US"{md5}", 5) == 0)
2245 {
2246 int sublen = Ustrlen(sub[1]+5);
2247 md5 base;
2248 uschar digest[16];
2249
2250 md5_start(&base);
2251 md5_end(&base, (uschar *)sub[0], Ustrlen(sub[0]), digest);
2252
2253 /* If the length that we are comparing against is 24, the MD5 digest
2254 is expressed as a base64 string. This is the way LDAP does it. However,
2255 some other software uses a straightforward hex representation. We assume
2256 this if the length is 32. Other lengths fail. */
2257
2258 if (sublen == 24)
2259 {
2260 uschar *coded = auth_b64encode((uschar *)digest, 16);
2261 DEBUG(D_auth) debug_printf("crypteq: using MD5+B64 hashing\n"
2262 " subject=%s\n crypted=%s\n", coded, sub[1]+5);
2263 *yield = (Ustrcmp(coded, sub[1]+5) == 0) == testfor;
2264 }
2265 else if (sublen == 32)
2266 {
2267 int i;
2268 uschar coded[36];
2269 for (i = 0; i < 16; i++) sprintf(CS (coded+2*i), "%02X", digest[i]);
2270 coded[32] = 0;
2271 DEBUG(D_auth) debug_printf("crypteq: using MD5+hex hashing\n"
2272 " subject=%s\n crypted=%s\n", coded, sub[1]+5);
2273 *yield = (strcmpic(coded, sub[1]+5) == 0) == testfor;
2274 }
2275 else
2276 {
2277 DEBUG(D_auth) debug_printf("crypteq: length for MD5 not 24 or 32: "
2278 "fail\n crypted=%s\n", sub[1]+5);
2279 *yield = !testfor;
2280 }
2281 }
2282
2283 else if (strncmpic(sub[1], US"{sha1}", 6) == 0)
2284 {
2285 int sublen = Ustrlen(sub[1]+6);
2286 sha1 base;
2287 uschar digest[20];
2288
2289 sha1_start(&base);
2290 sha1_end(&base, (uschar *)sub[0], Ustrlen(sub[0]), digest);
2291
2292 /* If the length that we are comparing against is 28, assume the SHA1
2293 digest is expressed as a base64 string. If the length is 40, assume a
2294 straightforward hex representation. Other lengths fail. */
2295
2296 if (sublen == 28)
2297 {
2298 uschar *coded = auth_b64encode((uschar *)digest, 20);
2299 DEBUG(D_auth) debug_printf("crypteq: using SHA1+B64 hashing\n"
2300 " subject=%s\n crypted=%s\n", coded, sub[1]+6);
2301 *yield = (Ustrcmp(coded, sub[1]+6) == 0) == testfor;
2302 }
2303 else if (sublen == 40)
2304 {
2305 int i;
2306 uschar coded[44];
2307 for (i = 0; i < 20; i++) sprintf(CS (coded+2*i), "%02X", digest[i]);
2308 coded[40] = 0;
2309 DEBUG(D_auth) debug_printf("crypteq: using SHA1+hex hashing\n"
2310 " subject=%s\n crypted=%s\n", coded, sub[1]+6);
2311 *yield = (strcmpic(coded, sub[1]+6) == 0) == testfor;
2312 }
2313 else
2314 {
2315 DEBUG(D_auth) debug_printf("crypteq: length for SHA-1 not 28 or 40: "
2316 "fail\n crypted=%s\n", sub[1]+6);
2317 *yield = !testfor;
2318 }
2319 }
2320
2321 else /* {crypt} or {crypt16} and non-{ at start */
2322 {
2323 int which = 0;
2324 uschar *coded;
2325
2326 if (strncmpic(sub[1], US"{crypt}", 7) == 0)
2327 {
2328 sub[1] += 7;
2329 which = 1;
2330 }
2331 else if (strncmpic(sub[1], US"{crypt16}", 9) == 0)
2332 {
2333 sub[1] += 9;
2334 which = 2;
2335 }
2336 else if (sub[1][0] == '{')
2337 {
2338 expand_string_message = string_sprintf("unknown encryption mechanism "
2339 "in \"%s\"", sub[1]);
2340 return NULL;
2341 }
2342
2343 switch(which)
2344 {
2345 case 0: coded = US DEFAULT_CRYPT(CS sub[0], CS sub[1]); break;
2346 case 1: coded = US crypt(CS sub[0], CS sub[1]); break;
2347 default: coded = US crypt16(CS sub[0], CS sub[1]); break;
2348 }
2349
2350 #define STR(s) # s
2351 #define XSTR(s) STR(s)
2352 DEBUG(D_auth) debug_printf("crypteq: using %s()\n"
2353 " subject=%s\n crypted=%s\n",
2354 (which == 0)? XSTR(DEFAULT_CRYPT) : (which == 1)? "crypt" : "crypt16",
2355 coded, sub[1]);
2356 #undef STR
2357 #undef XSTR
2358
2359 /* If the encrypted string contains fewer than two characters (for the
2360 salt), force failure. Otherwise we get false positives: with an empty
2361 string the yield of crypt() is an empty string! */
2362
2363 *yield = (Ustrlen(sub[1]) < 2)? !testfor :
2364 (Ustrcmp(coded, sub[1]) == 0) == testfor;
2365 }
2366 break;
2367 #endif /* SUPPORT_CRYPTEQ */
2368 } /* Switch for comparison conditions */
2369
2370 return s; /* End of comparison conditions */
2371
2372
2373 /* and/or: computes logical and/or of several conditions */
2374
2375 case ECOND_AND:
2376 case ECOND_OR:
2377 subcondptr = (yield == NULL)? NULL : &tempcond;
2378 combined_cond = (cond_type == ECOND_AND);
2379
2380 while (isspace(*s)) s++;
2381 if (*s++ != '{') goto COND_FAILED_CURLY_START;
2382
2383 for (;;)
2384 {
2385 while (isspace(*s)) s++;
2386 if (*s == '}') break;
2387 if (*s != '{')
2388 {
2389 expand_string_message = string_sprintf("each subcondition "
2390 "inside an \"%s{...}\" condition must be in its own {}", name);
2391 return NULL;
2392 }
2393
2394 s = eval_condition(s+1, subcondptr);
2395 if (s == NULL)
2396 {
2397 expand_string_message = string_sprintf("%s inside \"%s{...}\" condition",
2398 expand_string_message, name);
2399 return NULL;
2400 }
2401 while (isspace(*s)) s++;
2402
2403 if (*s++ != '}')
2404 {
2405 expand_string_message = string_sprintf("missing } at end of condition "
2406 "inside \"%s\" group", name);
2407 return NULL;
2408 }
2409
2410 if (yield != NULL)
2411 {
2412 if (cond_type == ECOND_AND)
2413 {
2414 combined_cond &= tempcond;
2415 if (!combined_cond) subcondptr = NULL; /* once false, don't */
2416 } /* evaluate any more */
2417 else
2418 {
2419 combined_cond |= tempcond;
2420 if (combined_cond) subcondptr = NULL; /* once true, don't */
2421 } /* evaluate any more */
2422 }
2423 }
2424
2425 if (yield != NULL) *yield = (combined_cond == testfor);
2426 return ++s;
2427
2428
2429 /* forall/forany: iterates a condition with different values */
2430
2431 case ECOND_FORALL:
2432 case ECOND_FORANY:
2433 {
2434 int sep = 0;
2435 uschar *save_iterate_item = iterate_item;
2436
2437 while (isspace(*s)) s++;
2438 if (*s++ != '{') goto COND_FAILED_CURLY_START;
2439 sub[0] = expand_string_internal(s, TRUE, &s, (yield == NULL));
2440 if (sub[0] == NULL) return NULL;
2441 if (*s++ != '}') goto COND_FAILED_CURLY_END;
2442
2443 while (isspace(*s)) s++;
2444 if (*s++ != '{') goto COND_FAILED_CURLY_START;
2445
2446 sub[1] = s;
2447
2448 /* Call eval_condition once, with result discarded (as if scanning a
2449 "false" part). This allows us to find the end of the condition, because if
2450 the list it empty, we won't actually evaluate the condition for real. */
2451
2452 s = eval_condition(sub[1], NULL);
2453 if (s == NULL)
2454 {
2455 expand_string_message = string_sprintf("%s inside \"%s\" condition",
2456 expand_string_message, name);
2457 return NULL;
2458 }
2459 while (isspace(*s)) s++;
2460
2461 if (*s++ != '}')
2462 {
2463 expand_string_message = string_sprintf("missing } at end of condition "
2464 "inside \"%s\"", name);
2465 return NULL;
2466 }
2467
2468 if (yield != NULL) *yield = !testfor;
2469 while ((iterate_item = string_nextinlist(&sub[0], &sep, NULL, 0)) != NULL)
2470 {
2471 DEBUG(D_expand) debug_printf("%s: $item = \"%s\"\n", name, iterate_item);
2472 if (eval_condition(sub[1], &tempcond) == NULL)
2473 {
2474 expand_string_message = string_sprintf("%s inside \"%s\" condition",
2475 expand_string_message, name);
2476 iterate_item = save_iterate_item;
2477 return NULL;
2478 }
2479 DEBUG(D_expand) debug_printf("%s: condition evaluated to %s\n", name,
2480 tempcond? "true":"false");
2481
2482 if (yield != NULL) *yield = (tempcond == testfor);
2483 if (tempcond == (cond_type == ECOND_FORANY)) break;
2484 }
2485
2486 iterate_item = save_iterate_item;
2487 return s;
2488 }
2489
2490
2491 /* The bool{} expansion condition maps a string to boolean.
2492 The values supported should match those supported by the ACL condition
2493 (acl.c, ACLC_CONDITION) so that we keep to a minimum the different ideas
2494 of true/false. Note that Router "condition" rules have a different
2495 interpretation, where general data can be used and only a few values
2496 map to FALSE.
2497 Note that readconf.c boolean matching, for boolean configuration options,
2498 only matches true/yes/false/no.
2499 The bool_lax{} condition matches the Router logic, which is much more
2500 liberal. */
2501 case ECOND_BOOL:
2502 case ECOND_BOOL_LAX:
2503 {
2504 uschar *sub_arg[1];
2505 uschar *t, *t2;
2506 uschar *ourname;
2507 size_t len;
2508 BOOL boolvalue = FALSE;
2509 while (isspace(*s)) s++;
2510 if (*s != '{') goto COND_FAILED_CURLY_START;
2511 ourname = cond_type == ECOND_BOOL_LAX ? US"bool_lax" : US"bool";
2512 switch(read_subs(sub_arg, 1, 1, &s, yield == NULL, FALSE, ourname))
2513 {
2514 case 1: expand_string_message = string_sprintf(
2515 "too few arguments or bracketing error for %s",
2516 ourname);
2517 /*FALLTHROUGH*/
2518 case 2:
2519 case 3: return NULL;
2520 }
2521 t = sub_arg[0];
2522 while (isspace(*t)) t++;
2523 len = Ustrlen(t);
2524 if (len)
2525 {
2526 /* trailing whitespace: seems like a good idea to ignore it too */
2527 t2 = t + len - 1;
2528 while (isspace(*t2)) t2--;
2529 if (t2 != (t + len))
2530 {
2531 *++t2 = '\0';
2532 len = t2 - t;
2533 }
2534 }
2535 DEBUG(D_expand)
2536 debug_printf("considering %s: %s\n", ourname, len ? t : US"<empty>");
2537 /* logic for the lax case from expand_check_condition(), which also does
2538 expands, and the logic is both short and stable enough that there should
2539 be no maintenance burden from replicating it. */
2540 if (len == 0)
2541 boolvalue = FALSE;
2542 else if (Ustrspn(t, "0123456789") == len)
2543 {
2544 boolvalue = (Uatoi(t) == 0) ? FALSE : TRUE;
2545 /* expand_check_condition only does a literal string "0" check */
2546 if ((cond_type == ECOND_BOOL_LAX) && (len > 1))
2547 boolvalue = TRUE;
2548 }
2549 else if (strcmpic(t, US"true") == 0 || strcmpic(t, US"yes") == 0)
2550 boolvalue = TRUE;
2551 else if (strcmpic(t, US"false") == 0 || strcmpic(t, US"no") == 0)
2552 boolvalue = FALSE;
2553 else if (cond_type == ECOND_BOOL_LAX)
2554 boolvalue = TRUE;
2555 else
2556 {
2557 expand_string_message = string_sprintf("unrecognised boolean "
2558 "value \"%s\"", t);
2559 return NULL;
2560 }
2561 if (yield != NULL) *yield = (boolvalue == testfor);
2562 return s;
2563 }
2564
2565 /* Unknown condition */
2566
2567 default:
2568 expand_string_message = string_sprintf("unknown condition \"%s\"", name);
2569 return NULL;
2570 } /* End switch on condition type */
2571
2572 /* Missing braces at start and end of data */
2573
2574 COND_FAILED_CURLY_START:
2575 expand_string_message = string_sprintf("missing { after \"%s\"", name);
2576 return NULL;
2577
2578 COND_FAILED_CURLY_END:
2579 expand_string_message = string_sprintf("missing } at end of \"%s\" condition",
2580 name);
2581 return NULL;
2582
2583 /* A condition requires code that is not compiled */
2584
2585 #if !defined(SUPPORT_PAM) || !defined(RADIUS_CONFIG_FILE) || \
2586 !defined(LOOKUP_LDAP) || !defined(CYRUS_PWCHECK_SOCKET) || \
2587 !defined(SUPPORT_CRYPTEQ) || !defined(CYRUS_SASLAUTHD_SOCKET)
2588 COND_FAILED_NOT_COMPILED:
2589 expand_string_message = string_sprintf("support for \"%s\" not compiled",
2590 name);
2591 return NULL;
2592 #endif
2593 }
2594
2595
2596
2597
2598 /*************************************************
2599 * Save numerical variables *
2600 *************************************************/
2601
2602 /* This function is called from items such as "if" that want to preserve and
2603 restore the numbered variables.
2604
2605 Arguments:
2606 save_expand_string points to an array of pointers to set
2607 save_expand_nlength points to an array of ints for the lengths
2608
2609 Returns: the value of expand max to save
2610 */
2611
2612 static int
2613 save_expand_strings(uschar **save_expand_nstring, int *save_expand_nlength)
2614 {
2615 int i;
2616 for (i = 0; i <= expand_nmax; i++)
2617 {
2618 save_expand_nstring[i] = expand_nstring[i];
2619 save_expand_nlength[i] = expand_nlength[i];
2620 }
2621 return expand_nmax;
2622 }
2623
2624
2625
2626 /*************************************************
2627 * Restore numerical variables *
2628 *************************************************/
2629
2630 /* This function restored saved values of numerical strings.
2631
2632 Arguments:
2633 save_expand_nmax the number of strings to restore
2634 save_expand_string points to an array of pointers
2635 save_expand_nlength points to an array of ints
2636
2637 Returns: nothing
2638 */
2639
2640 static void
2641 restore_expand_strings(int save_expand_nmax, uschar **save_expand_nstring,
2642 int *save_expand_nlength)
2643 {
2644 int i;
2645 expand_nmax = save_expand_nmax;
2646 for (i = 0; i <= expand_nmax; i++)
2647 {
2648 expand_nstring[i] = save_expand_nstring[i];
2649 expand_nlength[i] = save_expand_nlength[i];
2650 }
2651 }
2652
2653
2654
2655
2656
2657 /*************************************************
2658 * Handle yes/no substrings *
2659 *************************************************/
2660
2661 /* This function is used by ${if}, ${lookup} and ${extract} to handle the
2662 alternative substrings that depend on whether or not the condition was true,
2663 or the lookup or extraction succeeded. The substrings always have to be
2664 expanded, to check their syntax, but "skipping" is set when the result is not
2665 needed - this avoids unnecessary nested lookups.
2666
2667 Arguments:
2668 skipping TRUE if we were skipping when this item was reached
2669 yes TRUE if the first string is to be used, else use the second
2670 save_lookup a value to put back into lookup_value before the 2nd expansion
2671 sptr points to the input string pointer
2672 yieldptr points to the output string pointer
2673 sizeptr points to the output string size
2674 ptrptr points to the output string pointer
2675 type "lookup" or "if" or "extract" or "run", for error message
2676
2677 Returns: 0 OK; lookup_value has been reset to save_lookup
2678 1 expansion failed
2679 2 expansion failed because of bracketing error
2680 */
2681
2682 static int
2683 process_yesno(BOOL skipping, BOOL yes, uschar *save_lookup, uschar **sptr,
2684 uschar **yieldptr, int *sizeptr, int *ptrptr, uschar *type)
2685 {
2686 int rc = 0;
2687 uschar *s = *sptr; /* Local value */
2688 uschar *sub1, *sub2;
2689
2690 /* If there are no following strings, we substitute the contents of $value for
2691 lookups and for extractions in the success case. For the ${if item, the string
2692 "true" is substituted. In the fail case, nothing is substituted for all three
2693 items. */
2694
2695 while (isspace(*s)) s++;
2696 if (*s == '}')
2697 {
2698 if (type[0] == 'i')
2699 {
2700 if (yes) *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, US"true", 4);
2701 }
2702 else
2703 {
2704 if (yes && lookup_value != NULL)
2705 *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, lookup_value,
2706 Ustrlen(lookup_value));
2707 lookup_value = save_lookup;
2708 }
2709 s++;
2710 goto RETURN;
2711 }
2712
2713 /* The first following string must be braced. */
2714
2715 if (*s++ != '{') goto FAILED_CURLY;
2716
2717 /* Expand the first substring. Forced failures are noticed only if we actually
2718 want this string. Set skipping in the call in the fail case (this will always
2719 be the case if we were already skipping). */
2720
2721 sub1 = expand_string_internal(s, TRUE, &s, !yes);
2722 if (sub1 == NULL && (yes || !expand_string_forcedfail)) goto FAILED;
2723 expand_string_forcedfail = FALSE;
2724 if (*s++ != '}') goto FAILED_CURLY;
2725
2726 /* If we want the first string, add it to the output */
2727
2728 if (yes)
2729 *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, sub1, Ustrlen(sub1));
2730
2731 /* If this is called from a lookup or an extract, we want to restore $value to
2732 what it was at the start of the item, so that it has this value during the
2733 second string expansion. For the call from "if" or "run" to this function,
2734 save_lookup is set to lookup_value, so that this statement does nothing. */
2735
2736 lookup_value = save_lookup;
2737
2738 /* There now follows either another substring, or "fail", or nothing. This
2739 time, forced failures are noticed only if we want the second string. We must
2740 set skipping in the nested call if we don't want this string, or if we were
2741 already skipping. */
2742
2743 while (isspace(*s)) s++;
2744 if (*s == '{')
2745 {
2746 sub2 = expand_string_internal(s+1, TRUE, &s, yes || skipping);
2747 if (sub2 == NULL && (!yes || !expand_string_forcedfail)) goto FAILED;
2748 expand_string_forcedfail = FALSE;
2749 if (*s++ != '}') goto FAILED_CURLY;
2750
2751 /* If we want the second string, add it to the output */
2752
2753 if (!yes)
2754 *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, sub2, Ustrlen(sub2));
2755 }
2756
2757 /* If there is no second string, but the word "fail" is present when the use of
2758 the second string is wanted, set a flag indicating it was a forced failure
2759 rather than a syntactic error. Swallow the terminating } in case this is nested
2760 inside another lookup or if or extract. */
2761
2762 else if (*s != '}')
2763 {
2764 uschar name[256];
2765 s = read_name(name, sizeof(name), s, US"_");
2766 if (Ustrcmp(name, "fail") == 0)
2767 {
2768 if (!yes && !skipping)
2769 {
2770 while (isspace(*s)) s++;
2771 if (*s++ != '}') goto FAILED_CURLY;
2772 expand_string_message =
2773 string_sprintf("\"%s\" failed and \"fail\" requested", type);
2774 expand_string_forcedfail = TRUE;
2775 goto FAILED;
2776 }
2777 }
2778 else
2779 {
2780 expand_string_message =
2781 string_sprintf("syntax error in \"%s\" item - \"fail\" expected", type);
2782 goto FAILED;
2783 }
2784 }
2785
2786 /* All we have to do now is to check on the final closing brace. */
2787
2788 while (isspace(*s)) s++;
2789 if (*s++ == '}') goto RETURN;
2790
2791 /* Get here if there is a bracketing failure */
2792
2793 FAILED_CURLY:
2794 rc++;
2795
2796 /* Get here for other failures */
2797
2798 FAILED:
2799 rc++;
2800
2801 /* Update the input pointer value before returning */
2802
2803 RETURN:
2804 *sptr = s;
2805 return rc;
2806 }
2807
2808
2809
2810
2811 /*************************************************
2812 * Handle MD5 or SHA-1 computation for HMAC *
2813 *************************************************/
2814
2815 /* These are some wrapping functions that enable the HMAC code to be a bit
2816 cleaner. A good compiler will spot the tail recursion.
2817
2818 Arguments:
2819 type HMAC_MD5 or HMAC_SHA1
2820 remaining are as for the cryptographic hash functions
2821
2822 Returns: nothing
2823 */
2824
2825 static void
2826 chash_start(int type, void *base)
2827 {
2828 if (type == HMAC_MD5)
2829 md5_start((md5 *)base);
2830 else
2831 sha1_start((sha1 *)base);
2832 }
2833
2834 static void
2835 chash_mid(int type, void *base, uschar *string)
2836 {
2837 if (type == HMAC_MD5)
2838 md5_mid((md5 *)base, string);
2839 else
2840 sha1_mid((sha1 *)base, string);
2841 }
2842
2843 static void
2844 chash_end(int type, void *base, uschar *string, int length, uschar *digest)
2845 {
2846 if (type == HMAC_MD5)
2847 md5_end((md5 *)base, string, length, digest);
2848 else
2849 sha1_end((sha1 *)base, string, length, digest);
2850 }
2851
2852
2853
2854
2855
2856 /********************************************************
2857 * prvs: Get last three digits of days since Jan 1, 1970 *
2858 ********************************************************/
2859
2860 /* This is needed to implement the "prvs" BATV reverse
2861 path signing scheme
2862
2863 Argument: integer "days" offset to add or substract to
2864 or from the current number of days.
2865
2866 Returns: pointer to string containing the last three
2867 digits of the number of days since Jan 1, 1970,
2868 modified by the offset argument, NULL if there
2869 was an error in the conversion.
2870
2871 */
2872
2873 static uschar *
2874 prvs_daystamp(int day_offset)
2875 {
2876 uschar *days = store_get(32); /* Need at least 24 for cases */
2877 (void)string_format(days, 32, TIME_T_FMT, /* where TIME_T_FMT is %lld */
2878 (time(NULL) + day_offset*86400)/86400);
2879 return (Ustrlen(days) >= 3) ? &days[Ustrlen(days)-3] : US"100";
2880 }
2881
2882
2883
2884 /********************************************************
2885 * prvs: perform HMAC-SHA1 computation of prvs bits *
2886 ********************************************************/
2887
2888 /* This is needed to implement the "prvs" BATV reverse
2889 path signing scheme
2890
2891 Arguments:
2892 address RFC2821 Address to use
2893 key The key to use (must be less than 64 characters
2894 in size)
2895 key_num Single-digit key number to use. Defaults to
2896 '0' when NULL.
2897
2898 Returns: pointer to string containing the first three
2899 bytes of the final hash in hex format, NULL if
2900 there was an error in the process.
2901 */
2902
2903 static uschar *
2904 prvs_hmac_sha1(uschar *address, uschar *key, uschar *key_num, uschar *daystamp)
2905 {
2906 uschar *hash_source, *p;
2907 int size = 0,offset = 0,i;
2908 sha1 sha1_base;
2909 void *use_base = &sha1_base;
2910 uschar innerhash[20];
2911 uschar finalhash[20];
2912 uschar innerkey[64];
2913 uschar outerkey[64];
2914 uschar *finalhash_hex = store_get(40);
2915
2916 if (key_num == NULL)
2917 key_num = US"0";
2918
2919 if (Ustrlen(key) > 64)
2920 return NULL;
2921
2922 hash_source = string_cat(NULL,&size,&offset,key_num,1);
2923 string_cat(hash_source,&size,&offset,daystamp,3);
2924 string_cat(hash_source,&size,&offset,address,Ustrlen(address));
2925 hash_source[offset] = '\0';
2926
2927 DEBUG(D_expand) debug_printf("prvs: hash source is '%s'\n", hash_source);
2928
2929 memset(innerkey, 0x36, 64);
2930 memset(outerkey, 0x5c, 64);
2931
2932 for (i = 0; i < Ustrlen(key); i++)
2933 {
2934 innerkey[i] ^= key[i];
2935 outerkey[i] ^= key[i];
2936 }
2937
2938 chash_start(HMAC_SHA1, use_base);
2939 chash_mid(HMAC_SHA1, use_base, innerkey);
2940 chash_end(HMAC_SHA1, use_base, hash_source, offset, innerhash);
2941
2942 chash_start(HMAC_SHA1, use_base);
2943 chash_mid(HMAC_SHA1, use_base, outerkey);
2944 chash_end(HMAC_SHA1, use_base, innerhash, 20, finalhash);
2945
2946 p = finalhash_hex;
2947 for (i = 0; i < 3; i++)
2948 {
2949 *p++ = hex_digits[(finalhash[i] & 0xf0) >> 4];
2950 *p++ = hex_digits[finalhash[i] & 0x0f];
2951 }
2952 *p = '\0';
2953
2954 return finalhash_hex;
2955 }
2956
2957
2958
2959
2960 /*************************************************
2961 * Join a file onto the output string *
2962 *************************************************/
2963
2964 /* This is used for readfile and after a run expansion. It joins the contents
2965 of a file onto the output string, globally replacing newlines with a given
2966 string (optionally). The file is closed at the end.
2967
2968 Arguments:
2969 f the FILE
2970 yield pointer to the expandable string
2971 sizep pointer to the current size
2972 ptrp pointer to the current position
2973 eol newline replacement string, or NULL
2974
2975 Returns: new value of string pointer
2976 */
2977
2978 static uschar *
2979 cat_file(FILE *f, uschar *yield, int *sizep, int *ptrp, uschar *eol)
2980 {
2981 int eollen;
2982 uschar buffer[1024];
2983
2984 eollen = (eol == NULL)? 0 : Ustrlen(eol);
2985
2986 while (Ufgets(buffer, sizeof(buffer), f) != NULL)
2987 {
2988 int len = Ustrlen(buffer);
2989 if (eol != NULL && buffer[len-1] == '\n') len--;
2990 yield = string_cat(yield, sizep, ptrp, buffer, len);
2991 if (buffer[len] != 0)
2992 yield = string_cat(yield, sizep, ptrp, eol, eollen);
2993 }
2994
2995 if (yield != NULL) yield[*ptrp] = 0;
2996
2997 return yield;
2998 }
2999
3000
3001
3002
3003 /*************************************************
3004 * Evaluate numeric expression *
3005 *************************************************/
3006
3007 /* This is a set of mutually recursive functions that evaluate an arithmetic
3008 expression involving + - * / % & | ^ ~ << >> and parentheses. The only one of
3009 these functions that is called from elsewhere is eval_expr, whose interface is:
3010
3011 Arguments:
3012 sptr pointer to the pointer to the string - gets updated
3013 decimal TRUE if numbers are to be assumed decimal
3014 error pointer to where to put an error message - must be NULL on input
3015 endket TRUE if ')' must terminate - FALSE for external call
3016
3017 Returns: on success: the value of the expression, with *error still NULL
3018 on failure: an undefined value, with *error = a message
3019 */
3020
3021 static int eval_op_or(uschar **, BOOL, uschar **);
3022
3023
3024 static int
3025 eval_expr(uschar **sptr, BOOL decimal, uschar **error, BOOL endket)
3026 {
3027 uschar *s = *sptr;
3028 int x = eval_op_or(&s, decimal, error);
3029 if (*error == NULL)
3030 {
3031 if (endket)
3032 {
3033 if (*s != ')')
3034 *error = US"expecting closing parenthesis";
3035 else
3036 while (isspace(*(++s)));
3037 }
3038 else if (*s != 0) *error = US"expecting operator";
3039 }
3040 *sptr = s;
3041 return x;
3042 }
3043
3044
3045 static int
3046 eval_number(uschar **sptr, BOOL decimal, uschar **error)
3047 {
3048 register int c;
3049 int n;
3050 uschar *s = *sptr;
3051 while (isspace(*s)) s++;
3052 c = *s;
3053 if (isdigit(c))
3054 {
3055 int count;
3056 (void)sscanf(CS s, (decimal? "%d%n" : "%i%n"), &n, &count);
3057 s += count;
3058 if (tolower(*s) == 'k') { n *= 1024; s++; }
3059 else if (tolower(*s) == 'm') { n *= 1024*1024; s++; }
3060 while (isspace (*s)) s++;
3061 }
3062 else if (c == '(')
3063 {
3064 s++;
3065 n = eval_expr(&s, decimal, error, 1);
3066 }
3067 else
3068 {
3069 *error = US"expecting number or opening parenthesis";
3070 n = 0;
3071 }
3072 *sptr = s;
3073 return n;
3074 }
3075
3076
3077 static int eval_op_unary(uschar **sptr, BOOL decimal, uschar **error)
3078 {
3079 uschar *s = *sptr;
3080 int x;
3081 while (isspace(*s)) s++;
3082 if (*s == '+' || *s == '-' || *s == '~')
3083 {
3084 int op = *s++;
3085 x = eval_op_unary(&s, decimal, error);
3086 if (op == '-') x = -x;
3087 else if (op == '~') x = ~x;
3088 }
3089 else
3090 {
3091 x = eval_number(&s, decimal, error);
3092 }
3093 *sptr = s;
3094 return x;
3095 }
3096
3097
3098 static int eval_op_mult(uschar **sptr, BOOL decimal, uschar **error)
3099 {
3100 uschar *s = *sptr;
3101 int x = eval_op_unary(&s, decimal, error);
3102 if (*error == NULL)
3103 {
3104 while (*s == '*' || *s == '/' || *s == '%')
3105 {
3106 int op = *s++;
3107 int y = eval_op_unary(&s, decimal, error);
3108 if (*error != NULL) break;
3109 if (op == '*')
3110 x *= y;
3111 else
3112 {
3113 if (y == 0)
3114 {
3115 *error = (op == '/') ? US"divide by zero" : US"modulo by zero";
3116 x = 0;
3117 break;
3118 }
3119 if (op == '/')
3120 x /= y;
3121 else
3122 x %= y;
3123 }
3124 }
3125 }
3126 *sptr = s;
3127 return x;
3128 }
3129
3130
3131 static int eval_op_sum(uschar **sptr, BOOL decimal, uschar **error)
3132 {
3133 uschar *s = *sptr;
3134 int x = eval_op_mult(&s, decimal, error);
3135 if (*error == NULL)
3136 {
3137 while (*s == '+' || *s == '-')
3138 {
3139 int op = *s++;
3140 int y = eval_op_mult(&s, decimal, error);
3141 if (*error != NULL) break;
3142 if (op == '+') x += y; else x -= y;
3143 }
3144 }
3145 *sptr = s;
3146 return x;
3147 }
3148
3149
3150 static int eval_op_shift(uschar **sptr, BOOL decimal, uschar **error)
3151 {
3152 uschar *s = *sptr;
3153 int x = eval_op_sum(&s, decimal, error);
3154 if (*error == NULL)
3155 {
3156 while ((*s == '<' || *s == '>') && s[1] == s[0])
3157 {
3158 int y;
3159 int op = *s++;
3160 s++;
3161 y = eval_op_sum(&s, decimal, error);
3162 if (*error != NULL) break;
3163 if (op == '<') x <<= y; else x >>= y;
3164 }
3165 }
3166 *sptr = s;
3167 return x;
3168 }
3169
3170
3171 static int eval_op_and(uschar **sptr, BOOL decimal, uschar **error)
3172 {
3173 uschar *s = *sptr;
3174 int x = eval_op_shift(&s, decimal, error);
3175 if (*error == NULL)
3176 {
3177 while (*s == '&')
3178 {
3179 int y;
3180 s++;
3181 y = eval_op_shift(&s, decimal, error);
3182 if (*error != NULL) break;
3183 x &= y;
3184 }
3185 }
3186 *sptr = s;
3187 return x;
3188 }
3189
3190
3191 static int eval_op_xor(uschar **sptr, BOOL decimal, uschar **error)
3192 {
3193 uschar *s = *sptr;
3194 int x = eval_op_and(&s, decimal, error);
3195 if (*error == NULL)
3196 {
3197 while (*s == '^')
3198 {
3199 int y;
3200 s++;
3201 y = eval_op_and(&s, decimal, error);
3202 if (*error != NULL) break;
3203 x ^= y;
3204 }
3205 }
3206 *sptr = s;
3207 return x;
3208 }
3209
3210
3211 static int eval_op_or(uschar **sptr, BOOL decimal, uschar **error)
3212 {
3213 uschar *s = *sptr;
3214 int x = eval_op_xor(&s, decimal, error);
3215 if (*error == NULL)
3216 {
3217 while (*s == '|')
3218 {
3219 int y;
3220 s++;
3221 y = eval_op_xor(&s, decimal, error);
3222 if (*error != NULL) break;
3223 x |= y;
3224 }
3225 }
3226 *sptr = s;
3227 return x;
3228 }
3229
3230
3231
3232 /*************************************************
3233 * Expand string *
3234 *************************************************/
3235
3236 /* Returns either an unchanged string, or the expanded string in stacking pool
3237 store. Interpreted sequences are:
3238
3239 \... normal escaping rules
3240 $name substitutes the variable
3241 ${name} ditto
3242 ${op:string} operates on the expanded string value
3243 ${item{arg1}{arg2}...} expands the args and then does the business
3244 some literal args are not enclosed in {}
3245
3246 There are now far too many operators and item types to make it worth listing
3247 them here in detail any more.
3248
3249 We use an internal routine recursively to handle embedded substrings. The
3250 external function follows. The yield is NULL if the expansion failed, and there
3251 are two cases: if something collapsed syntactically, or if "fail" was given
3252 as the action on a lookup failure. These can be distinguised by looking at the
3253 variable expand_string_forcedfail, which is TRUE in the latter case.
3254
3255 The skipping flag is set true when expanding a substring that isn't actually
3256 going to be used (after "if" or "lookup") and it prevents lookups from
3257 happening lower down.
3258
3259 Store usage: At start, a store block of the length of the input plus 64
3260 is obtained. This is expanded as necessary by string_cat(), which might have to
3261 get a new block, or might be able to expand the original. At the end of the
3262 function we can release any store above that portion of the yield block that
3263 was actually used. In many cases this will be optimal.
3264
3265 However: if the first item in the expansion is a variable name or header name,
3266 we reset the store before processing it; if the result is in fresh store, we
3267 use that without copying. This is helpful for expanding strings like
3268 $message_headers which can get very long.
3269
3270 There's a problem if a ${dlfunc item has side-effects that cause allocation,
3271 since resetting the store at the end of the expansion will free store that was
3272 allocated by the plugin code as well as the slop after the expanded string. So
3273 we skip any resets if ${dlfunc has been used. This is an unfortunate
3274 consequence of string expansion becoming too powerful.
3275
3276 Arguments:
3277 string the string to be expanded
3278 ket_ends true if expansion is to stop at }
3279 left if not NULL, a pointer to the first character after the
3280 expansion is placed here (typically used with ket_ends)
3281 skipping TRUE for recursive calls when the value isn't actually going
3282 to be used (to allow for optimisation)
3283
3284 Returns: NULL if expansion fails:
3285 expand_string_forcedfail is set TRUE if failure was forced
3286 expand_string_message contains a textual error message
3287 a pointer to the expanded string on success
3288 */
3289
3290 static uschar *
3291 expand_string_internal(uschar *string, BOOL ket_ends, uschar **left,
3292 BOOL skipping)
3293 {
3294 int ptr = 0;
3295 int size = Ustrlen(string)+ 64;
3296 int item_type;
3297 uschar *yield = store_get(size);
3298 uschar *s = string;
3299 uschar *save_expand_nstring[EXPAND_MAXN+1];
3300 int save_expand_nlength[EXPAND_MAXN+1];
3301 BOOL resetok = TRUE;
3302
3303 expand_string_forcedfail = FALSE;
3304 expand_string_message = US"";
3305
3306 while (*s != 0)
3307 {
3308 uschar *value;
3309 uschar name[256];
3310
3311 /* \ escapes the next character, which must exist, or else
3312 the expansion fails. There's a special escape, \N, which causes
3313 copying of the subject verbatim up to the next \N. Otherwise,
3314 the escapes are the standard set. */
3315
3316 if (*s == '\\')
3317 {
3318 if (s[1] == 0)
3319 {
3320 expand_string_message = US"\\ at end of string";
3321 goto EXPAND_FAILED;
3322 }
3323
3324 if (s[1] == 'N')
3325 {
3326 uschar *t = s + 2;
3327 for (s = t; *s != 0; s++) if (*s == '\\' && s[1] == 'N') break;
3328 yield = string_cat(yield, &size, &ptr, t, s - t);
3329 if (*s != 0) s += 2;
3330 }
3331
3332 else
3333 {
3334 uschar ch[1];
3335 ch[0] = string_interpret_escape(&s);
3336 s++;
3337 yield = string_cat(yield, &size, &ptr, ch, 1);
3338 }
3339
3340 continue;
3341 }
3342
3343 /* Anything other than $ is just copied verbatim, unless we are
3344 looking for a terminating } character. */
3345
3346 if (ket_ends && *s == '}') break;
3347
3348 if (*s != '$')
3349 {
3350 yield = string_cat(yield, &size, &ptr, s++, 1);
3351 continue;
3352 }
3353
3354 /* No { after the $ - must be a plain name or a number for string
3355 match variable. There has to be a fudge for variables that are the
3356 names of header fields preceded by "$header_" because header field
3357 names can contain any printing characters except space and colon.
3358 For those that don't like typing this much, "$h_" is a synonym for
3359 "$header_". A non-existent header yields a NULL value; nothing is
3360 inserted. */
3361
3362 if (isalpha((*(++s))))
3363 {
3364 int len;
3365 int newsize = 0;
3366
3367 s = read_name(name, sizeof(name), s, US"_");
3368
3369 /* If this is the first thing to be expanded, release the pre-allocated
3370 buffer. */
3371
3372 if (ptr == 0 && yield != NULL)
3373 {
3374 if (resetok) store_reset(yield);
3375 yield = NULL;
3376 size = 0;
3377 }
3378
3379 /* Header */
3380
3381 if (Ustrncmp(name, "h_", 2) == 0 ||
3382 Ustrncmp(name, "rh_", 3) == 0 ||
3383 Ustrncmp(name, "bh_", 3) == 0 ||
3384 Ustrncmp(name, "header_", 7) == 0 ||
3385 Ustrncmp(name, "rheader_", 8) == 0 ||
3386 Ustrncmp(name, "bheader_", 8) == 0)
3387 {
3388 BOOL want_raw = (name[0] == 'r')? TRUE : FALSE;
3389 uschar *charset = (name[0] == 'b')? NULL : headers_charset;
3390 s = read_header_name(name, sizeof(name), s);
3391 value = find_header(name, FALSE, &newsize, want_raw, charset);
3392
3393 /* If we didn't find the header, and the header contains a closing brace
3394 character, this may be a user error where the terminating colon
3395 has been omitted. Set a flag to adjust the error message in this case.
3396 But there is no error here - nothing gets inserted. */
3397
3398 if (value == NULL)
3399 {
3400 if (Ustrchr(name, '}') != NULL) malformed_header = TRUE;
3401 continue;
3402 }
3403 }
3404
3405 /* Variable */
3406
3407 else
3408 {
3409 value = find_variable(name, FALSE, skipping, &newsize);
3410 if (value == NULL)
3411 {
3412 expand_string_message =
3413 string_sprintf("unknown variable name \"%s\"", name);
3414 check_variable_error_message(name);
3415 goto EXPAND_FAILED;
3416 }
3417 }
3418
3419 /* If the data is known to be in a new buffer, newsize will be set to the
3420 size of that buffer. If this is the first thing in an expansion string,
3421 yield will be NULL; just point it at the new store instead of copying. Many
3422 expansion strings contain just one reference, so this is a useful
3423 optimization, especially for humungous headers. */
3424
3425 len = Ustrlen(value);
3426 if (yield == NULL && newsize != 0)
3427 {
3428 yield = value;
3429 size = newsize;
3430 ptr = len;
3431 }
3432 else yield = string_cat(yield, &size, &ptr, value, len);
3433
3434 continue;
3435 }
3436
3437 if (isdigit(*s))
3438 {
3439 int n;
3440 s = read_number(&n, s);
3441 if (n >= 0 && n <= expand_nmax)
3442 yield = string_cat(yield, &size, &ptr, expand_nstring[n],
3443 expand_nlength[n]);
3444 continue;
3445 }
3446
3447 /* Otherwise, if there's no '{' after $ it's an error. */
3448
3449 if (*s != '{')
3450 {
3451 expand_string_message = US"$ not followed by letter, digit, or {";
3452 goto EXPAND_FAILED;
3453 }
3454
3455 /* After { there can be various things, but they all start with
3456 an initial word, except for a number for a string match variable. */
3457
3458 if (isdigit((*(++s))))
3459 {
3460 int n;
3461 s = read_number(&n, s);
3462 if (*s++ != '}')
3463 {
3464 expand_string_message = US"} expected after number";
3465 goto EXPAND_FAILED;
3466 }
3467 if (n >= 0 && n <= expand_nmax)
3468 yield = string_cat(yield, &size, &ptr, expand_nstring[n],
3469 expand_nlength[n]);
3470 continue;
3471 }
3472
3473 if (!isalpha(*s))
3474 {
3475 expand_string_message = US"letter or digit expected after ${";
3476 goto EXPAND_FAILED;
3477 }
3478
3479 /* Allow "-" in names to cater for substrings with negative
3480 arguments. Since we are checking for known names after { this is
3481 OK. */
3482
3483 s = read_name(name, sizeof(name), s, US"_-");
3484 item_type = chop_match(name, item_table, sizeof(item_table)/sizeof(uschar *));
3485
3486 switch(item_type)
3487 {
3488 /* Handle conditionals - preserve the values of the numerical expansion
3489 variables in case they get changed by a regular expression match in the
3490 condition. If not, they retain their external settings. At the end
3491 of this "if" section, they get restored to their previous values. */
3492
3493 case EITEM_IF:
3494 {
3495 BOOL cond = FALSE;
3496 uschar *next_s;
3497 int save_expand_nmax =
3498 save_expand_strings(save_expand_nstring, save_expand_nlength);
3499
3500 while (isspace(*s)) s++;
3501 next_s = eval_condition(s, skipping? NULL : &cond);
3502 if (next_s == NULL) goto EXPAND_FAILED; /* message already set */
3503
3504 DEBUG(D_expand)
3505 debug_printf("condition: %.*s\n result: %s\n", (int)(next_s - s), s,
3506 cond? "true" : "false");
3507
3508 s = next_s;
3509
3510 /* The handling of "yes" and "no" result strings is now in a separate
3511 function that is also used by ${lookup} and ${extract} and ${run}. */
3512
3513 switch(process_yesno(
3514 skipping, /* were previously skipping */
3515 cond, /* success/failure indicator */
3516 lookup_value, /* value to reset for string2 */
3517 &s, /* input pointer */
3518 &yield, /* output pointer */
3519 &size, /* output size */
3520 &ptr, /* output current point */
3521 US"if")) /* condition type */
3522 {
3523 case 1: goto EXPAND_FAILED; /* when all is well, the */
3524 case 2: goto EXPAND_FAILED_CURLY; /* returned value is 0 */
3525 }
3526
3527 /* Restore external setting of expansion variables for continuation
3528 at this level. */
3529
3530 restore_expand_strings(save_expand_nmax, save_expand_nstring,
3531 save_expand_nlength);
3532 continue;
3533 }
3534
3535 /* Handle database lookups unless locked out. If "skipping" is TRUE, we are
3536 expanding an internal string that isn't actually going to be used. All we
3537 need to do is check the syntax, so don't do a lookup at all. Preserve the
3538 values of the numerical expansion variables in case they get changed by a
3539 partial lookup. If not, they retain their external settings. At the end
3540 of this "lookup" section, they get restored to their previous values. */
3541
3542 case EITEM_LOOKUP:
3543 {
3544 int stype, partial, affixlen, starflags;
3545 int expand_setup = 0;
3546 int nameptr = 0;
3547 uschar *key, *filename, *affix;
3548 uschar *save_lookup_value = lookup_value;
3549 int save_expand_nmax =
3550 save_expand_strings(save_expand_nstring, save_expand_nlength);
3551
3552 if ((expand_forbid & RDO_LOOKUP) != 0)
3553 {
3554 expand_string_message = US"lookup expansions are not permitted";
3555 goto EXPAND_FAILED;
3556 }
3557
3558 /* Get the key we are to look up for single-key+file style lookups.
3559 Otherwise set the key NULL pro-tem. */
3560
3561 while (isspace(*s)) s++;
3562 if (*s == '{')
3563 {
3564 key = expand_string_internal(s+1, TRUE, &s, skipping);
3565 if (key == NULL) goto EXPAND_FAILED;
3566 if (*s++ != '}') goto EXPAND_FAILED_CURLY;
3567 while (isspace(*s)) s++;
3568 }
3569 else key = NULL;
3570
3571 /* Find out the type of database */
3572
3573 if (!isalpha(*s))
3574 {
3575 expand_string_message = US"missing lookup type";
3576 goto EXPAND_FAILED;
3577 }
3578
3579 /* The type is a string that may contain special characters of various
3580 kinds. Allow everything except space or { to appear; the actual content
3581 is checked by search_findtype_partial. */
3582
3583 while (*s != 0 && *s != '{' && !isspace(*s))
3584 {
3585 if (nameptr < sizeof(name) - 1) name[nameptr++] = *s;
3586 s++;
3587 }
3588 name[nameptr] = 0;
3589 while (isspace(*s)) s++;
3590
3591 /* Now check for the individual search type and any partial or default
3592 options. Only those types that are actually in the binary are valid. */
3593
3594 stype = search_findtype_partial(name, &partial, &affix, &affixlen,
3595 &starflags);
3596 if (stype < 0)
3597 {
3598 expand_string_message = search_error_message;
3599 goto EXPAND_FAILED;
3600 }
3601
3602 /* Check that a key was provided for those lookup types that need it,
3603 and was not supplied for those that use the query style. */
3604
3605 if (!mac_islookup(stype, lookup_querystyle|lookup_absfilequery))
3606 {
3607 if (key == NULL)
3608 {
3609 expand_string_message = string_sprintf("missing {key} for single-"
3610 "key \"%s\" lookup", name);
3611 goto EXPAND_FAILED;
3612 }
3613 }
3614 else
3615 {
3616 if (key != NULL)
3617 {
3618 expand_string_message = string_sprintf("a single key was given for "
3619 "lookup type \"%s\", which is not a single-key lookup type", name);
3620 goto EXPAND_FAILED;
3621 }
3622 }
3623
3624 /* Get the next string in brackets and expand it. It is the file name for
3625 single-key+file lookups, and the whole query otherwise. In the case of
3626 queries that also require a file name (e.g. sqlite), the file name comes
3627 first. */
3628
3629 if (*s != '{') goto EXPAND_FAILED_CURLY;
3630 filename = expand_string_internal(s+1, TRUE, &s, skipping);
3631 if (filename == NULL) goto EXPAND_FAILED;
3632 if (*s++ != '}') goto EXPAND_FAILED_CURLY;
3633 while (isspace(*s)) s++;
3634
3635 /* If this isn't a single-key+file lookup, re-arrange the variables
3636 to be appropriate for the search_ functions. For query-style lookups,
3637 there is just a "key", and no file name. For the special query-style +
3638 file types, the query (i.e. "key") starts with a file name. */
3639
3640 if (key == NULL)
3641 {
3642 while (isspace(*filename)) filename++;
3643 key = filename;
3644
3645 if (mac_islookup(stype, lookup_querystyle))
3646 {
3647 filename = NULL;
3648 }
3649 else
3650 {
3651 if (*filename != '/')
3652 {
3653 expand_string_message = string_sprintf(
3654 "absolute file name expected for \"%s\" lookup", name);
3655 goto EXPAND_FAILED;
3656 }
3657 while (*key != 0 && !isspace(*key)) key++;
3658 if (*key != 0) *key++ = 0;
3659 }
3660 }
3661
3662 /* If skipping, don't do the next bit - just lookup_value == NULL, as if
3663 the entry was not found. Note that there is no search_close() function.
3664 Files are left open in case of re-use. At suitable places in higher logic,
3665 search_tidyup() is called to tidy all open files. This can save opening
3666 the same file several times. However, files may also get closed when
3667 others are opened, if too many are open at once. The rule is that a
3668 handle should not be used after a second search_open().
3669
3670 Request that a partial search sets up $1 and maybe $2 by passing
3671 expand_setup containing zero. If its value changes, reset expand_nmax,
3672 since new variables will have been set. Note that at the end of this
3673 "lookup" section, the old numeric variables are restored. */
3674
3675 if (skipping)
3676 lookup_value = NULL;
3677 else
3678 {
3679 void *handle = search_open(filename, stype, 0, NULL, NULL);
3680 if (handle == NULL)
3681 {
3682 expand_string_message = search_error_message;
3683 goto EXPAND_FAILED;
3684 }
3685 lookup_value = search_find(handle, filename, key, partial, affix,
3686 affixlen, starflags, &expand_setup);
3687 if (search_find_defer)
3688 {
3689 expand_string_message =
3690 string_sprintf("lookup of \"%s\" gave DEFER: %s",
3691 string_printing2(key, FALSE), search_error_message);
3692 goto EXPAND_FAILED;
3693 }
3694 if (expand_setup > 0) expand_nmax = expand_setup;
3695 }
3696
3697 /* The handling of "yes" and "no" result strings is now in a separate
3698 function that is also used by ${if} and ${extract}. */
3699
3700 switch(process_yesno(
3701 skipping, /* were previously skipping */
3702 lookup_value != NULL, /* success/failure indicator */
3703 save_lookup_value, /* value to reset for string2 */
3704 &s, /* input pointer */
3705 &yield, /* output pointer */
3706 &size, /* output size */
3707 &ptr, /* output current point */
3708 US"lookup")) /* condition type */
3709 {
3710 case 1: goto EXPAND_FAILED; /* when all is well, the */
3711 case 2: goto EXPAND_FAILED_CURLY; /* returned value is 0 */
3712 }
3713
3714 /* Restore external setting of expansion variables for carrying on
3715 at this level, and continue. */
3716
3717 restore_expand_strings(save_expand_nmax, save_expand_nstring,
3718 save_expand_nlength);
3719 continue;
3720 }
3721
3722 /* If Perl support is configured, handle calling embedded perl subroutines,
3723 unless locked out at this time. Syntax is ${perl{sub}} or ${perl{sub}{arg}}
3724 or ${perl{sub}{arg1}{arg2}} or up to a maximum of EXIM_PERL_MAX_ARGS
3725 arguments (defined below). */
3726
3727 #define EXIM_PERL_MAX_ARGS 8
3728
3729 case EITEM_PERL:
3730 #ifndef EXIM_PERL
3731 expand_string_message = US"\"${perl\" encountered, but this facility "
3732 "is not included in this binary";
3733 goto EXPAND_FAILED;
3734
3735 #else /* EXIM_PERL */
3736 {
3737 uschar *sub_arg[EXIM_PERL_MAX_ARGS + 2];
3738 uschar *new_yield;
3739
3740 if ((expand_forbid & RDO_PERL) != 0)
3741 {
3742 expand_string_message = US"Perl calls are not permitted";
3743 goto EXPAND_FAILED;
3744 }
3745
3746 switch(read_subs(sub_arg, EXIM_PERL_MAX_ARGS + 1, 1, &s, skipping, TRUE,
3747 US"perl"))
3748 {
3749 case 1: goto EXPAND_FAILED_CURLY;
3750 case 2:
3751 case 3: goto EXPAND_FAILED;
3752 }
3753
3754 /* If skipping, we don't actually do anything */
3755
3756 if (skipping) continue;
3757
3758 /* Start the interpreter if necessary */
3759
3760 if (!opt_perl_started)
3761 {
3762 uschar *initerror;
3763 if (opt_perl_startup == NULL)
3764 {
3765 expand_string_message = US"A setting of perl_startup is needed when "
3766 "using the Perl interpreter";
3767 goto EXPAND_FAILED;
3768 }
3769 DEBUG(D_any) debug_printf("Starting Perl interpreter\n");
3770 initerror = init_perl(opt_perl_startup);
3771 if (initerror != NULL)
3772 {
3773 expand_string_message =
3774 string_sprintf("error in perl_startup code: %s\n", initerror);
3775 goto EXPAND_FAILED;
3776 }
3777 opt_perl_started = TRUE;
3778 }
3779
3780 /* Call the function */
3781
3782 sub_arg[EXIM_PERL_MAX_ARGS + 1] = NULL;
3783 new_yield = call_perl_cat(yield, &size, &ptr, &expand_string_message,
3784 sub_arg[0], sub_arg + 1);
3785
3786 /* NULL yield indicates failure; if the message pointer has been set to
3787 NULL, the yield was undef, indicating a forced failure. Otherwise the
3788 message will indicate some kind of Perl error. */
3789
3790 if (new_yield == NULL)
3791 {
3792 if (expand_string_message == NULL)
3793 {
3794 expand_string_message =
3795 string_sprintf("Perl subroutine \"%s\" returned undef to force "
3796 "failure", sub_arg[0]);
3797 expand_string_forcedfail = TRUE;
3798 }
3799 goto EXPAND_FAILED;
3800 }
3801
3802 /* Yield succeeded. Ensure forcedfail is unset, just in case it got
3803 set during a callback from Perl. */
3804
3805 expand_string_forcedfail = FALSE;
3806 yield = new_yield;
3807 continue;
3808 }
3809 #endif /* EXIM_PERL */
3810
3811 /* Transform email address to "prvs" scheme to use
3812 as BATV-signed return path */
3813
3814 case EITEM_PRVS:
3815 {
3816 uschar *sub_arg[3];
3817 uschar *p,*domain;
3818
3819 switch(read_subs(sub_arg, 3, 2, &s, skipping, TRUE, US"prvs"))
3820 {
3821 case 1: goto EXPAND_FAILED_CURLY;
3822 case 2:
3823 case 3: goto EXPAND_FAILED;
3824 }
3825
3826 /* If skipping, we don't actually do anything */
3827 if (skipping) continue;
3828
3829 /* sub_arg[0] is the address */
3830 domain = Ustrrchr(sub_arg[0],'@');
3831 if ( (domain == NULL) || (domain == sub_arg[0]) || (Ustrlen(domain) == 1) )
3832 {
3833 expand_string_message = US"prvs first argument must be a qualified email address";
3834 goto EXPAND_FAILED;
3835 }
3836
3837 /* Calculate the hash. The second argument must be a single-digit
3838 key number, or unset. */
3839
3840 if (sub_arg[2] != NULL &&
3841 (!isdigit(sub_arg[2][0]) || sub_arg[2][1] != 0))
3842 {
3843 expand_string_message = US"prvs second argument must be a single digit";
3844 goto EXPAND_FAILED;
3845 }
3846
3847 p = prvs_hmac_sha1(sub_arg[0],sub_arg[1],sub_arg[2],prvs_daystamp(7));
3848 if (p == NULL)
3849 {
3850 expand_string_message = US"prvs hmac-sha1 conversion failed";
3851 goto EXPAND_FAILED;
3852 }
3853
3854 /* Now separate the domain from the local part */
3855 *domain++ = '\0';
3856
3857 yield = string_cat(yield,&size,&ptr,US"prvs=",5);
3858 string_cat(yield,&size,&ptr,(sub_arg[2] != NULL) ? sub_arg[2] : US"0", 1);
3859 string_cat(yield,&size,&ptr,prvs_daystamp(7),3);
3860 string_cat(yield,&size,&ptr,p,6);
3861 string_cat(yield,&size,&ptr,US"=",1);
3862 string_cat(yield,&size,&ptr,sub_arg[0],Ustrlen(sub_arg[0]));
3863 string_cat(yield,&size,&ptr,US"@",1);
3864 string_cat(yield,&size,&ptr,domain,Ustrlen(domain));
3865
3866 continue;
3867 }
3868
3869 /* Check a prvs-encoded address for validity */
3870
3871 case EITEM_PRVSCHECK:
3872 {
3873 uschar *sub_arg[3];
3874 int mysize = 0, myptr = 0;
3875 const pcre *re;
3876 uschar *p;
3877
3878 /* TF: Ugliness: We want to expand parameter 1 first, then set
3879 up expansion variables that are used in the expansion of
3880 parameter 2. So we clone the string for the first
3881 expansion, where we only expand parameter 1.
3882
3883 PH: Actually, that isn't necessary. The read_subs() function is
3884 designed to work this way for the ${if and ${lookup expansions. I've
3885 tidied the code.
3886 */
3887
3888 /* Reset expansion variables */
3889 prvscheck_result = NULL;
3890 prvscheck_address = NULL;
3891 prvscheck_keynum = NULL;
3892
3893 switch(read_subs(sub_arg, 1, 1, &s, skipping, FALSE, US"prvs"))
3894 {
3895 case 1: goto EXPAND_FAILED_CURLY;
3896 case 2:
3897 case 3: goto EXPAND_FAILED;
3898 }
3899
3900 re = regex_must_compile(US"^prvs\\=([0-9])([0-9]{3})([A-F0-9]{6})\\=(.+)\\@(.+)$",
3901 TRUE,FALSE);
3902
3903 if (regex_match_and_setup(re,sub_arg[0],0,-1))
3904 {
3905 uschar *local_part = string_copyn(expand_nstring[4],expand_nlength[4]);
3906 uschar *key_num = string_copyn(expand_nstring[1],expand_nlength[1]);
3907 uschar *daystamp = string_copyn(expand_nstring[2],expand_nlength[2]);
3908 uschar *hash = string_copyn(expand_nstring[3],expand_nlength[3]);
3909 uschar *domain = string_copyn(expand_nstring[5],expand_nlength[5]);
3910
3911 DEBUG(D_expand) debug_printf("prvscheck localpart: %s\n", local_part);
3912 DEBUG(D_expand) debug_printf("prvscheck key number: %s\n", key_num);
3913 DEBUG(D_expand) debug_printf("prvscheck daystamp: %s\n", daystamp);
3914 DEBUG(D_expand) debug_printf("prvscheck hash: %s\n", hash);
3915 DEBUG(D_expand) debug_printf("prvscheck domain: %s\n", domain);
3916
3917 /* Set up expansion variables */
3918 prvscheck_address = string_cat(NULL, &mysize, &myptr, local_part, Ustrlen(local_part));
3919 string_cat(prvscheck_address,&mysize,&myptr,US"@",1);
3920 string_cat(prvscheck_address,&mysize,&myptr,domain,Ustrlen(domain));
3921 prvscheck_address[myptr] = '\0';
3922 prvscheck_keynum = string_copy(key_num);
3923
3924 /* Now expand the second argument */
3925 switch(read_subs(sub_arg, 1, 1, &s, skipping, FALSE, US"prvs"))
3926 {
3927 case 1: goto EXPAND_FAILED_CURLY;
3928 case 2:
3929 case 3: goto EXPAND_FAILED;
3930 }
3931
3932 /* Now we have the key and can check the address. */
3933
3934 p = prvs_hmac_sha1(prvscheck_address, sub_arg[0], prvscheck_keynum,
3935 daystamp);
3936
3937 if (p == NULL)
3938 {
3939 expand_string_message