Output the warning log line about deferring conditions in "warn"
[exim.git] / src / src / acl.c
1 /* $Cambridge: exim/src/src/acl.c,v 1.31 2005/05/17 11:20:32 ph10 Exp $ */
2
3 /*************************************************
4 * Exim - an Internet mail transport agent *
5 *************************************************/
6
7 /* Copyright (c) University of Cambridge 1995 - 2005 */
8 /* See the file NOTICE for conditions of use and distribution. */
9
10 /* Code for handling Access Control Lists (ACLs) */
11
12 #include "exim.h"
13
14
15 /* Default callout timeout */
16
17 #define CALLOUT_TIMEOUT_DEFAULT 30
18
19 /* ACL verb codes - keep in step with the table of verbs that follows */
20
21 enum { ACL_ACCEPT, ACL_DEFER, ACL_DENY, ACL_DISCARD, ACL_DROP, ACL_REQUIRE,
22 ACL_WARN };
23
24 /* ACL verbs */
25
26 static uschar *verbs[] =
27 { US"accept", US"defer", US"deny", US"discard", US"drop", US"require",
28 US"warn" };
29
30 /* For each verb, the condition for which "message" is used */
31
32 static int msgcond[] = { FAIL, OK, OK, FAIL, OK, FAIL, OK };
33
34 /* ACL condition and modifier codes - keep in step with the table that
35 follows. */
36
37 enum { ACLC_ACL, ACLC_AUTHENTICATED,
38 #ifdef EXPERIMENTAL_BRIGHTMAIL
39 ACLC_BMI_OPTIN,
40 #endif
41 ACLC_CONDITION, ACLC_CONTROL,
42 #ifdef WITH_CONTENT_SCAN
43 ACLC_DECODE,
44 #endif
45 ACLC_DELAY,
46 #ifdef WITH_OLD_DEMIME
47 ACLC_DEMIME,
48 #endif
49 #ifdef EXPERIMENTAL_DOMAINKEYS
50 ACLC_DK_DOMAIN_SOURCE,
51 ACLC_DK_POLICY,
52 ACLC_DK_SENDER_DOMAINS,
53 ACLC_DK_SENDER_LOCAL_PARTS,
54 ACLC_DK_SENDERS,
55 ACLC_DK_STATUS,
56 #endif
57 ACLC_DNSLISTS, ACLC_DOMAINS, ACLC_ENCRYPTED, ACLC_ENDPASS,
58 ACLC_HOSTS, ACLC_LOCAL_PARTS, ACLC_LOG_MESSAGE, ACLC_LOGWRITE,
59 #ifdef WITH_CONTENT_SCAN
60 ACLC_MALWARE,
61 #endif
62 ACLC_MESSAGE,
63 #ifdef WITH_CONTENT_SCAN
64 ACLC_MIME_REGEX,
65 #endif
66 ACLC_RECIPIENTS,
67 #ifdef WITH_CONTENT_SCAN
68 ACLC_REGEX,
69 #endif
70 ACLC_SENDER_DOMAINS, ACLC_SENDERS, ACLC_SET,
71 #ifdef WITH_CONTENT_SCAN
72 ACLC_SPAM,
73 #endif
74 #ifdef EXPERIMENTAL_SPF
75 ACLC_SPF,
76 #endif
77 ACLC_VERIFY };
78
79 /* ACL conditions/modifiers: "delay", "control", "endpass", "message",
80 "log_message", "logwrite", and "set" are modifiers that look like conditions
81 but always return TRUE. They are used for their side effects. */
82
83 static uschar *conditions[] = { US"acl", US"authenticated",
84 #ifdef EXPERIMENTAL_BRIGHTMAIL
85 US"bmi_optin",
86 #endif
87 US"condition",
88 US"control",
89 #ifdef WITH_CONTENT_SCAN
90 US"decode",
91 #endif
92 US"delay",
93 #ifdef WITH_OLD_DEMIME
94 US"demime",
95 #endif
96 #ifdef EXPERIMENTAL_DOMAINKEYS
97 US"dk_domain_source",
98 US"dk_policy",
99 US"dk_sender_domains",
100 US"dk_sender_local_parts",
101 US"dk_senders",
102 US"dk_status",
103 #endif
104 US"dnslists", US"domains", US"encrypted",
105 US"endpass", US"hosts", US"local_parts", US"log_message", US"logwrite",
106 #ifdef WITH_CONTENT_SCAN
107 US"malware",
108 #endif
109 US"message",
110 #ifdef WITH_CONTENT_SCAN
111 US"mime_regex",
112 #endif
113 US"recipients",
114 #ifdef WITH_CONTENT_SCAN
115 US"regex",
116 #endif
117 US"sender_domains", US"senders", US"set",
118 #ifdef WITH_CONTENT_SCAN
119 US"spam",
120 #endif
121 #ifdef EXPERIMENTAL_SPF
122 US"spf",
123 #endif
124 US"verify" };
125
126 /* ACL control names */
127
128 static uschar *controls[] = { US"error", US"caseful_local_part",
129 US"caselower_local_part", US"enforce_sync", US"no_enforce_sync", US"freeze",
130 US"queue_only", US"submission", US"no_multiline"};
131
132 /* Flags to indicate for which conditions /modifiers a string expansion is done
133 at the outer level. In the other cases, expansion already occurs in the
134 checking functions. */
135
136 static uschar cond_expand_at_top[] = {
137 TRUE, /* acl */
138 FALSE, /* authenticated */
139 #ifdef EXPERIMENTAL_BRIGHTMAIL
140 TRUE, /* bmi_optin */
141 #endif
142 TRUE, /* condition */
143 TRUE, /* control */
144 #ifdef WITH_CONTENT_SCAN
145 TRUE, /* decode */
146 #endif
147 TRUE, /* delay */
148 #ifdef WITH_OLD_DEMIME
149 TRUE, /* demime */
150 #endif
151 #ifdef EXPERIMENTAL_DOMAINKEYS
152 TRUE, /* dk_domain_source */
153 TRUE, /* dk_policy */
154 TRUE, /* dk_sender_domains */
155 TRUE, /* dk_sender_local_parts */
156 TRUE, /* dk_senders */
157 TRUE, /* dk_status */
158 #endif
159 TRUE, /* dnslists */
160 FALSE, /* domains */
161 FALSE, /* encrypted */
162 TRUE, /* endpass */
163 FALSE, /* hosts */
164 FALSE, /* local_parts */
165 TRUE, /* log_message */
166 TRUE, /* logwrite */
167 #ifdef WITH_CONTENT_SCAN
168 TRUE, /* malware */
169 #endif
170 TRUE, /* message */
171 #ifdef WITH_CONTENT_SCAN
172 TRUE, /* mime_regex */
173 #endif
174 FALSE, /* recipients */
175 #ifdef WITH_CONTENT_SCAN
176 TRUE, /* regex */
177 #endif
178 FALSE, /* sender_domains */
179 FALSE, /* senders */
180 TRUE, /* set */
181 #ifdef WITH_CONTENT_SCAN
182 TRUE, /* spam */
183 #endif
184 #ifdef EXPERIMENTAL_SPF
185 TRUE, /* spf */
186 #endif
187 TRUE /* verify */
188 };
189
190 /* Flags to identify the modifiers */
191
192 static uschar cond_modifiers[] = {
193 FALSE, /* acl */
194 FALSE, /* authenticated */
195 #ifdef EXPERIMENTAL_BRIGHTMAIL
196 TRUE, /* bmi_optin */
197 #endif
198 FALSE, /* condition */
199 TRUE, /* control */
200 #ifdef WITH_CONTENT_SCAN
201 FALSE, /* decode */
202 #endif
203 TRUE, /* delay */
204 #ifdef WITH_OLD_DEMIME
205 FALSE, /* demime */
206 #endif
207 #ifdef EXPERIMENTAL_DOMAINKEYS
208 FALSE, /* dk_domain_source */
209 FALSE, /* dk_policy */
210 FALSE, /* dk_sender_domains */
211 FALSE, /* dk_sender_local_parts */
212 FALSE, /* dk_senders */
213 FALSE, /* dk_status */
214 #endif
215 FALSE, /* dnslists */
216 FALSE, /* domains */
217 FALSE, /* encrypted */
218 TRUE, /* endpass */
219 FALSE, /* hosts */
220 FALSE, /* local_parts */
221 TRUE, /* log_message */
222 TRUE, /* logwrite */
223 #ifdef WITH_CONTENT_SCAN
224 FALSE, /* malware */
225 #endif
226 TRUE, /* message */
227 #ifdef WITH_CONTENT_SCAN
228 FALSE, /* mime_regex */
229 #endif
230 FALSE, /* recipients */
231 #ifdef WITH_CONTENT_SCAN
232 FALSE, /* regex */
233 #endif
234 FALSE, /* sender_domains */
235 FALSE, /* senders */
236 TRUE, /* set */
237 #ifdef WITH_CONTENT_SCAN
238 FALSE, /* spam */
239 #endif
240 #ifdef EXPERIMENTAL_SPF
241 FALSE, /* spf */
242 #endif
243 FALSE /* verify */
244 };
245
246 /* Bit map vector of which conditions are not allowed at certain times. For
247 each condition, there's a bitmap of dis-allowed times. For some, it is easier
248 to specify the negation of a small number of allowed times. */
249
250 static unsigned int cond_forbids[] = {
251 0, /* acl */
252
253 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_CONNECT)| /* authenticated */
254 (1<<ACL_WHERE_HELO),
255
256 #ifdef EXPERIMENTAL_BRIGHTMAIL
257 (1<<ACL_WHERE_AUTH)| /* bmi_optin */
258 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
259 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_MIME)|
260 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
261 (1<<ACL_WHERE_MAILAUTH)|
262 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
263 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_PREDATA),
264 #endif
265
266 0, /* condition */
267
268 /* Certain types of control are always allowed, so we let it through
269 always and check in the control processing itself. */
270
271 0, /* control */
272
273 #ifdef WITH_CONTENT_SCAN
274 (unsigned int)
275 ~(1<<ACL_WHERE_MIME), /* decode */
276 #endif
277
278 0, /* delay */
279
280 #ifdef WITH_OLD_DEMIME
281 (unsigned int)
282 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)), /* demime */
283 #endif
284
285 #ifdef EXPERIMENTAL_DOMAINKEYS
286 (1<<ACL_WHERE_AUTH)| /* dk_domain_source */
287 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
288 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
289 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
290 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
291 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
292 (1<<ACL_WHERE_VRFY),
293
294 (1<<ACL_WHERE_AUTH)| /* dk_policy */
295 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
296 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
297 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
298 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
299 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
300 (1<<ACL_WHERE_VRFY),
301
302 (1<<ACL_WHERE_AUTH)| /* dk_sender_domains */
303 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
304 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
305 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
306 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
307 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
308 (1<<ACL_WHERE_VRFY),
309
310 (1<<ACL_WHERE_AUTH)| /* dk_sender_local_parts */
311 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
312 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
313 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
314 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
315 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
316 (1<<ACL_WHERE_VRFY),
317
318 (1<<ACL_WHERE_AUTH)| /* dk_senders */
319 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
320 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
321 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
322 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
323 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
324 (1<<ACL_WHERE_VRFY),
325
326 (1<<ACL_WHERE_AUTH)| /* dk_status */
327 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
328 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
329 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
330 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
331 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
332 (1<<ACL_WHERE_VRFY),
333 #endif
334
335 (1<<ACL_WHERE_NOTSMTP), /* dnslists */
336
337 (unsigned int)
338 ~(1<<ACL_WHERE_RCPT), /* domains */
339
340 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_CONNECT)| /* encrypted */
341 (1<<ACL_WHERE_HELO),
342
343 0, /* endpass */
344
345 (1<<ACL_WHERE_NOTSMTP), /* hosts */
346
347 (unsigned int)
348 ~(1<<ACL_WHERE_RCPT), /* local_parts */
349
350 0, /* log_message */
351
352 0, /* logwrite */
353
354 #ifdef WITH_CONTENT_SCAN
355 (unsigned int)
356 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)), /* malware */
357 #endif
358
359 0, /* message */
360
361 #ifdef WITH_CONTENT_SCAN
362 (unsigned int)
363 ~(1<<ACL_WHERE_MIME), /* mime_regex */
364 #endif
365
366 (unsigned int)
367 ~(1<<ACL_WHERE_RCPT), /* recipients */
368
369 #ifdef WITH_CONTENT_SCAN
370 (unsigned int)
371 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* regex */
372 (1<<ACL_WHERE_MIME)),
373 #endif
374
375 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* sender_domains */
376 (1<<ACL_WHERE_HELO)|
377 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
378 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
379 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
380
381 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* senders */
382 (1<<ACL_WHERE_HELO)|
383 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
384 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
385 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
386
387 0, /* set */
388
389 #ifdef WITH_CONTENT_SCAN
390 (unsigned int)
391 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)), /* spam */
392 #endif
393
394 #ifdef EXPERIMENTAL_SPF
395 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* spf */
396 (1<<ACL_WHERE_HELO)|
397 (1<<ACL_WHERE_MAILAUTH)|
398 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
399 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
400 #endif
401
402 /* Certain types of verify are always allowed, so we let it through
403 always and check in the verify function itself */
404
405 0 /* verify */
406 };
407
408
409 /* Return values from decode_control() */
410
411 enum {
412 #ifdef EXPERIMENTAL_BRIGHTMAIL
413 CONTROL_BMI_RUN,
414 #endif
415 #ifdef EXPERIMENTAL_DOMAINKEYS
416 CONTROL_DK_VERIFY,
417 #endif
418 CONTROL_ERROR, CONTROL_CASEFUL_LOCAL_PART, CONTROL_CASELOWER_LOCAL_PART,
419 CONTROL_ENFORCE_SYNC, CONTROL_NO_ENFORCE_SYNC, CONTROL_FREEZE,
420 CONTROL_QUEUE_ONLY, CONTROL_SUBMISSION,
421 #ifdef WITH_CONTENT_SCAN
422 CONTROL_NO_MBOX_UNSPOOL,
423 #endif
424 CONTROL_FAKEREJECT, CONTROL_NO_MULTILINE };
425
426 /* Bit map vector of which controls are not allowed at certain times. For
427 each control, there's a bitmap of dis-allowed times. For some, it is easier to
428 specify the negation of a small number of allowed times. */
429
430 static unsigned int control_forbids[] = {
431 #ifdef EXPERIMENTAL_BRIGHTMAIL
432 0, /* bmi_run */
433 #endif
434 #ifdef EXPERIMENTAL_DOMAINKEYS
435 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), /* dk_verify */
436 #endif
437
438 0, /* error */
439
440 (unsigned int)
441 ~(1<<ACL_WHERE_RCPT), /* caseful_local_part */
442
443 (unsigned int)
444 ~(1<<ACL_WHERE_RCPT), /* caselower_local_part */
445
446 (1<<ACL_WHERE_NOTSMTP), /* enforce_sync */
447
448 (1<<ACL_WHERE_NOTSMTP), /* no_enforce_sync */
449
450 (unsigned int)
451 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* freeze */
452 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
453 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)),
454
455 (unsigned int)
456 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* queue_only */
457 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
458 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)),
459
460 (unsigned int)
461 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* submission */
462 (1<<ACL_WHERE_PREDATA)),
463
464 #ifdef WITH_CONTENT_SCAN
465 (unsigned int)
466 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* no_mbox_unspool */
467 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
468 (1<<ACL_WHERE_MIME)),
469 #endif
470
471 (unsigned int)
472 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakereject */
473 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
474 (1<<ACL_WHERE_MIME)),
475
476 (1<<ACL_WHERE_NOTSMTP) /* no_multiline */
477 };
478
479 /* Structure listing various control arguments, with their characteristics. */
480
481 typedef struct control_def {
482 uschar *name;
483 int value; /* CONTROL_xxx value */
484 BOOL has_option; /* Has /option(s) following */
485 } control_def;
486
487 static control_def controls_list[] = {
488 #ifdef EXPERIMENTAL_BRIGHTMAIL
489 { US"bmi_run", CONTROL_BMI_RUN, FALSE},
490 #endif
491 #ifdef EXPERIMENTAL_DOMAINKEYS
492 { US"dk_verify", CONTROL_DK_VERIFY, FALSE},
493 #endif
494 { US"caseful_local_part", CONTROL_CASEFUL_LOCAL_PART, FALSE},
495 { US"caselower_local_part", CONTROL_CASELOWER_LOCAL_PART, FALSE},
496 { US"enforce_sync", CONTROL_ENFORCE_SYNC, FALSE},
497 { US"freeze", CONTROL_FREEZE, FALSE},
498 { US"no_enforce_sync", CONTROL_NO_ENFORCE_SYNC, FALSE},
499 { US"no_multiline_responses", CONTROL_NO_MULTILINE, FALSE},
500 { US"queue_only", CONTROL_QUEUE_ONLY, FALSE},
501 #ifdef WITH_CONTENT_SCAN
502 { US"no_mbox_unspool", CONTROL_NO_MBOX_UNSPOOL, FALSE},
503 #endif
504 { US"fakereject", CONTROL_FAKEREJECT, TRUE},
505 { US"submission", CONTROL_SUBMISSION, TRUE}
506 };
507
508 /* Support data structures for Client SMTP Authorization. acl_verify_csa()
509 caches its result in a tree to avoid repeated DNS queries. The result is an
510 integer code which is used as an index into the following tables of
511 explanatory strings and verification return codes. */
512
513 static tree_node *csa_cache = NULL;
514
515 enum { CSA_UNKNOWN, CSA_OK, CSA_DEFER_SRV, CSA_DEFER_ADDR,
516 CSA_FAIL_EXPLICIT, CSA_FAIL_DOMAIN, CSA_FAIL_NOADDR, CSA_FAIL_MISMATCH };
517
518 /* The acl_verify_csa() return code is translated into an acl_verify() return
519 code using the following table. It is OK unless the client is definitely not
520 authorized. This is because CSA is supposed to be optional for sending sites,
521 so recipients should not be too strict about checking it - especially because
522 DNS problems are quite likely to occur. It's possible to use $csa_status in
523 further ACL conditions to distinguish ok, unknown, and defer if required, but
524 the aim is to make the usual configuration simple. */
525
526 static int csa_return_code[] = {
527 OK, OK, OK, OK,
528 FAIL, FAIL, FAIL, FAIL
529 };
530
531 static uschar *csa_status_string[] = {
532 US"unknown", US"ok", US"defer", US"defer",
533 US"fail", US"fail", US"fail", US"fail"
534 };
535
536 static uschar *csa_reason_string[] = {
537 US"unknown",
538 US"ok",
539 US"deferred (SRV lookup failed)",
540 US"deferred (target address lookup failed)",
541 US"failed (explicit authorization required)",
542 US"failed (host name not authorized)",
543 US"failed (no authorized addresses)",
544 US"failed (client address mismatch)"
545 };
546
547 /* Enable recursion between acl_check_internal() and acl_check_condition() */
548
549 static int acl_check_internal(int, address_item *, uschar *, int, uschar **,
550 uschar **);
551
552
553 /*************************************************
554 * Pick out name from list *
555 *************************************************/
556
557 /* Use a binary chop method
558
559 Arguments:
560 name name to find
561 list list of names
562 end size of list
563
564 Returns: offset in list, or -1 if not found
565 */
566
567 static int
568 acl_checkname(uschar *name, uschar **list, int end)
569 {
570 int start = 0;
571
572 while (start < end)
573 {
574 int mid = (start + end)/2;
575 int c = Ustrcmp(name, list[mid]);
576 if (c == 0) return mid;
577 if (c < 0) end = mid; else start = mid + 1;
578 }
579
580 return -1;
581 }
582
583
584 /*************************************************
585 * Read and parse one ACL *
586 *************************************************/
587
588 /* This function is called both from readconf in order to parse the ACLs in the
589 configuration file, and also when an ACL is encountered dynamically (e.g. as
590 the result of an expansion). It is given a function to call in order to
591 retrieve the lines of the ACL. This function handles skipping comments and
592 blank lines (where relevant).
593
594 Arguments:
595 func function to get next line of ACL
596 error where to put an error message
597
598 Returns: pointer to ACL, or NULL
599 NULL can be legal (empty ACL); in this case error will be NULL
600 */
601
602 acl_block *
603 acl_read(uschar *(*func)(void), uschar **error)
604 {
605 acl_block *yield = NULL;
606 acl_block **lastp = &yield;
607 acl_block *this = NULL;
608 acl_condition_block *cond;
609 acl_condition_block **condp = NULL;
610 uschar *s;
611
612 *error = NULL;
613
614 while ((s = (*func)()) != NULL)
615 {
616 int v, c;
617 BOOL negated = FALSE;
618 uschar *saveline = s;
619 uschar name[64];
620
621 /* Conditions (but not verbs) are allowed to be negated by an initial
622 exclamation mark. */
623
624 while (isspace(*s)) s++;
625 if (*s == '!')
626 {
627 negated = TRUE;
628 s++;
629 }
630
631 /* Read the name of a verb or a condition, or the start of a new ACL, which
632 can be started by a name, or by a macro definition. */
633
634 s = readconf_readname(name, sizeof(name), s);
635 if (*s == ':' || isupper(name[0] && *s == '=')) return yield;
636
637 /* If a verb is unrecognized, it may be another condition or modifier that
638 continues the previous verb. */
639
640 v = acl_checkname(name, verbs, sizeof(verbs)/sizeof(char *));
641 if (v < 0)
642 {
643 if (this == NULL)
644 {
645 *error = string_sprintf("unknown ACL verb in \"%s\"", saveline);
646 return NULL;
647 }
648 }
649
650 /* New verb */
651
652 else
653 {
654 if (negated)
655 {
656 *error = string_sprintf("malformed ACL line \"%s\"", saveline);
657 return NULL;
658 }
659 this = store_get(sizeof(acl_block));
660 *lastp = this;
661 lastp = &(this->next);
662 this->next = NULL;
663 this->verb = v;
664 this->condition = NULL;
665 condp = &(this->condition);
666 if (*s == 0) continue; /* No condition on this line */
667 if (*s == '!')
668 {
669 negated = TRUE;
670 s++;
671 }
672 s = readconf_readname(name, sizeof(name), s); /* Condition name */
673 }
674
675 /* Handle a condition or modifier. */
676
677 c = acl_checkname(name, conditions, sizeof(conditions)/sizeof(char *));
678 if (c < 0)
679 {
680 *error = string_sprintf("unknown ACL condition/modifier in \"%s\"",
681 saveline);
682 return NULL;
683 }
684
685 /* The modifiers may not be negated */
686
687 if (negated && cond_modifiers[c])
688 {
689 *error = string_sprintf("ACL error: negation is not allowed with "
690 "\"%s\"", conditions[c]);
691 return NULL;
692 }
693
694 /* ENDPASS may occur only with ACCEPT or DISCARD. */
695
696 if (c == ACLC_ENDPASS &&
697 this->verb != ACL_ACCEPT &&
698 this->verb != ACL_DISCARD)
699 {
700 *error = string_sprintf("ACL error: \"%s\" is not allowed with \"%s\"",
701 conditions[c], verbs[this->verb]);
702 return NULL;
703 }
704
705 cond = store_get(sizeof(acl_condition_block));
706 cond->next = NULL;
707 cond->type = c;
708 cond->u.negated = negated;
709
710 *condp = cond;
711 condp = &(cond->next);
712
713 /* The "set" modifier is different in that its argument is "name=value"
714 rather than just a value, and we can check the validity of the name, which
715 gives us a variable number to insert into the data block. */
716
717 if (c == ACLC_SET)
718 {
719 if (Ustrncmp(s, "acl_", 4) != 0 || (s[4] != 'c' && s[4] != 'm') ||
720 !isdigit(s[5]) || (!isspace(s[6]) && s[6] != '='))
721 {
722 *error = string_sprintf("unrecognized name after \"set\" in ACL "
723 "modifier \"set %s\"", s);
724 return NULL;
725 }
726
727 cond->u.varnumber = s[5] - '0';
728 if (s[4] == 'm') cond->u.varnumber += ACL_C_MAX;
729 s += 6;
730 while (isspace(*s)) s++;
731 }
732
733 /* For "set", we are now positioned for the data. For the others, only
734 "endpass" has no data */
735
736 if (c != ACLC_ENDPASS)
737 {
738 if (*s++ != '=')
739 {
740 *error = string_sprintf("\"=\" missing after ACL \"%s\" %s", name,
741 cond_modifiers[c]? US"modifier" : US"condition");
742 return NULL;
743 }
744 while (isspace(*s)) s++;
745 cond->arg = string_copy(s);
746 }
747 }
748
749 return yield;
750 }
751
752
753
754 /*************************************************
755 * Handle warnings *
756 *************************************************/
757
758 /* This function is called when a WARN verb's conditions are true. It adds to
759 the message's headers, and/or writes information to the log. In each case, this
760 only happens once (per message for headers, per connection for log).
761
762 Arguments:
763 where ACL_WHERE_xxxx indicating which ACL this is
764 user_message message for adding to headers
765 log_message message for logging, if different
766
767 Returns: nothing
768 */
769
770 static void
771 acl_warn(int where, uschar *user_message, uschar *log_message)
772 {
773 int hlen;
774
775 if (log_message != NULL && log_message != user_message)
776 {
777 uschar *text;
778 string_item *logged;
779
780 text = string_sprintf("%s Warning: %s", host_and_ident(TRUE),
781 string_printing(log_message));
782
783 /* If a sender verification has failed, and the log message is "sender verify
784 failed", add the failure message. */
785
786 if (sender_verified_failed != NULL &&
787 sender_verified_failed->message != NULL &&
788 strcmpic(log_message, US"sender verify failed") == 0)
789 text = string_sprintf("%s: %s", text, sender_verified_failed->message);
790
791 /* Search previously logged warnings. They are kept in malloc
792 store so they can be freed at the start of a new message. */
793
794 for (logged = acl_warn_logged; logged != NULL; logged = logged->next)
795 if (Ustrcmp(logged->text, text) == 0) break;
796
797 if (logged == NULL)
798 {
799 int length = Ustrlen(text) + 1;
800 log_write(0, LOG_MAIN, "%s", text);
801 logged = store_malloc(sizeof(string_item) + length);
802 logged->text = (uschar *)logged + sizeof(string_item);
803 memcpy(logged->text, text, length);
804 logged->next = acl_warn_logged;
805 acl_warn_logged = logged;
806 }
807 }
808
809 /* If there's no user message, we are done. */
810
811 if (user_message == NULL) return;
812
813 /* If this isn't a message ACL, we can't do anything with a user message.
814 Log an error. */
815
816 if (where > ACL_WHERE_NOTSMTP)
817 {
818 log_write(0, LOG_MAIN|LOG_PANIC, "ACL \"warn\" with \"message\" setting "
819 "found in a non-message (%s) ACL: cannot specify header lines here: "
820 "message ignored", acl_wherenames[where]);
821 return;
822 }
823
824 /* Treat the user message as a sequence of one or more header lines. */
825
826 hlen = Ustrlen(user_message);
827 if (hlen > 0)
828 {
829 uschar *text, *p, *q;
830
831 /* Add a final newline if not present */
832
833 text = ((user_message)[hlen-1] == '\n')? user_message :
834 string_sprintf("%s\n", user_message);
835
836 /* Loop for multiple header lines, taking care about continuations */
837
838 for (p = q = text; *p != 0; )
839 {
840 uschar *s;
841 int newtype = htype_add_bot;
842 header_line **hptr = &acl_warn_headers;
843
844 /* Find next header line within the string */
845
846 for (;;)
847 {
848 q = Ustrchr(q, '\n');
849 if (*(++q) != ' ' && *q != '\t') break;
850 }
851
852 /* If the line starts with a colon, interpret the instruction for where to
853 add it. This temporarily sets up a new type. */
854
855 if (*p == ':')
856 {
857 if (strncmpic(p, US":after_received:", 16) == 0)
858 {
859 newtype = htype_add_rec;
860 p += 16;
861 }
862 else if (strncmpic(p, US":at_start_rfc:", 14) == 0)
863 {
864 newtype = htype_add_rfc;
865 p += 14;
866 }
867 else if (strncmpic(p, US":at_start:", 10) == 0)
868 {
869 newtype = htype_add_top;
870 p += 10;
871 }
872 else if (strncmpic(p, US":at_end:", 8) == 0)
873 {
874 newtype = htype_add_bot;
875 p += 8;
876 }
877 while (*p == ' ' || *p == '\t') p++;
878 }
879
880 /* See if this line starts with a header name, and if not, add X-ACL-Warn:
881 to the front of it. */
882
883 for (s = p; s < q - 1; s++)
884 {
885 if (*s == ':' || !isgraph(*s)) break;
886 }
887
888 s = string_sprintf("%s%.*s", (*s == ':')? "" : "X-ACL-Warn: ", q - p, p);
889 hlen = Ustrlen(s);
890
891 /* See if this line has already been added */
892
893 while (*hptr != NULL)
894 {
895 if (Ustrncmp((*hptr)->text, s, hlen) == 0) break;
896 hptr = &((*hptr)->next);
897 }
898
899 /* Add if not previously present */
900
901 if (*hptr == NULL)
902 {
903 header_line *h = store_get(sizeof(header_line));
904 h->text = s;
905 h->next = NULL;
906 h->type = newtype;
907 h->slen = hlen;
908 *hptr = h;
909 hptr = &(h->next);
910 }
911
912 /* Advance for next header line within the string */
913
914 p = q;
915 }
916 }
917 }
918
919
920
921 /*************************************************
922 * Verify and check reverse DNS *
923 *************************************************/
924
925 /* Called from acl_verify() below. We look up the host name(s) of the client IP
926 address if this has not yet been done. The host_name_lookup() function checks
927 that one of these names resolves to an address list that contains the client IP
928 address, so we don't actually have to do the check here.
929
930 Arguments:
931 user_msgptr pointer for user message
932 log_msgptr pointer for log message
933
934 Returns: OK verification condition succeeded
935 FAIL verification failed
936 DEFER there was a problem verifying
937 */
938
939 static int
940 acl_verify_reverse(uschar **user_msgptr, uschar **log_msgptr)
941 {
942 int rc;
943
944 user_msgptr = user_msgptr; /* stop compiler warning */
945
946 /* Previous success */
947
948 if (sender_host_name != NULL) return OK;
949
950 /* Previous failure */
951
952 if (host_lookup_failed)
953 {
954 *log_msgptr = string_sprintf("host lookup failed%s", host_lookup_msg);
955 return FAIL;
956 }
957
958 /* Need to do a lookup */
959
960 HDEBUG(D_acl)
961 debug_printf("looking up host name to force name/address consistency check\n");
962
963 if ((rc = host_name_lookup()) != OK)
964 {
965 *log_msgptr = (rc == DEFER)?
966 US"host lookup deferred for reverse lookup check"
967 :
968 string_sprintf("host lookup failed for reverse lookup check%s",
969 host_lookup_msg);
970 return rc; /* DEFER or FAIL */
971 }
972
973 host_build_sender_fullhost();
974 return OK;
975 }
976
977
978
979 /*************************************************
980 * Check client IP address matches CSA target *
981 *************************************************/
982
983 /* Called from acl_verify_csa() below. This routine scans a section of a DNS
984 response for address records belonging to the CSA target hostname. The section
985 is specified by the reset argument, either RESET_ADDITIONAL or RESET_ANSWERS.
986 If one of the addresses matches the client's IP address, then the client is
987 authorized by CSA. If there are target IP addresses but none of them match
988 then the client is using an unauthorized IP address. If there are no target IP
989 addresses then the client cannot be using an authorized IP address. (This is
990 an odd configuration - why didn't the SRV record have a weight of 1 instead?)
991
992 Arguments:
993 dnsa the DNS answer block
994 dnss a DNS scan block for us to use
995 reset option specifing what portion to scan, as described above
996 target the target hostname to use for matching RR names
997
998 Returns: CSA_OK successfully authorized
999 CSA_FAIL_MISMATCH addresses found but none matched
1000 CSA_FAIL_NOADDR no target addresses found
1001 */
1002
1003 static int
1004 acl_verify_csa_address(dns_answer *dnsa, dns_scan *dnss, int reset,
1005 uschar *target)
1006 {
1007 dns_record *rr;
1008 dns_address *da;
1009
1010 BOOL target_found = FALSE;
1011
1012 for (rr = dns_next_rr(dnsa, dnss, reset);
1013 rr != NULL;
1014 rr = dns_next_rr(dnsa, dnss, RESET_NEXT))
1015 {
1016 /* Check this is an address RR for the target hostname. */
1017
1018 if (rr->type != T_A
1019 #if HAVE_IPV6
1020 && rr->type != T_AAAA
1021 #ifdef SUPPORT_A6
1022 && rr->type != T_A6
1023 #endif
1024 #endif
1025 ) continue;
1026
1027 if (strcmpic(target, rr->name) != 0) continue;
1028
1029 target_found = TRUE;
1030
1031 /* Turn the target address RR into a list of textual IP addresses and scan
1032 the list. There may be more than one if it is an A6 RR. */
1033
1034 for (da = dns_address_from_rr(dnsa, rr); da != NULL; da = da->next)
1035 {
1036 /* If the client IP address matches the target IP address, it's good! */
1037
1038 DEBUG(D_acl) debug_printf("CSA target address is %s\n", da->address);
1039
1040 if (strcmpic(sender_host_address, da->address) == 0) return CSA_OK;
1041 }
1042 }
1043
1044 /* If we found some target addresses but none of them matched, the client is
1045 using an unauthorized IP address, otherwise the target has no authorized IP
1046 addresses. */
1047
1048 if (target_found) return CSA_FAIL_MISMATCH;
1049 else return CSA_FAIL_NOADDR;
1050 }
1051
1052
1053
1054 /*************************************************
1055 * Verify Client SMTP Authorization *
1056 *************************************************/
1057
1058 /* Called from acl_verify() below. This routine calls dns_lookup_special()
1059 to find the CSA SRV record corresponding to the domain argument, or
1060 $sender_helo_name if no argument is provided. It then checks that the
1061 client is authorized, and that its IP address corresponds to the SRV
1062 target's address by calling acl_verify_csa_address() above. The address
1063 should have been returned in the DNS response's ADDITIONAL section, but if
1064 not we perform another DNS lookup to get it.
1065
1066 Arguments:
1067 domain pointer to optional parameter following verify = csa
1068
1069 Returns: CSA_UNKNOWN no valid CSA record found
1070 CSA_OK successfully authorized
1071 CSA_FAIL_* client is definitely not authorized
1072 CSA_DEFER_* there was a DNS problem
1073 */
1074
1075 static int
1076 acl_verify_csa(uschar *domain)
1077 {
1078 tree_node *t;
1079 uschar *found, *p;
1080 int priority, weight, port;
1081 dns_answer dnsa;
1082 dns_scan dnss;
1083 dns_record *rr;
1084 int rc, type;
1085 uschar target[256];
1086
1087 /* Work out the domain we are using for the CSA lookup. The default is the
1088 client's HELO domain. If the client has not said HELO, use its IP address
1089 instead. If it's a local client (exim -bs), CSA isn't applicable. */
1090
1091 while (isspace(*domain) && *domain != '\0') ++domain;
1092 if (*domain == '\0') domain = sender_helo_name;
1093 if (domain == NULL) domain = sender_host_address;
1094 if (sender_host_address == NULL) return CSA_UNKNOWN;
1095
1096 /* If we have an address literal, strip off the framing ready for turning it
1097 into a domain. The framing consists of matched square brackets possibly
1098 containing a keyword and a colon before the actual IP address. */
1099
1100 if (domain[0] == '[')
1101 {
1102 uschar *start = Ustrchr(domain, ':');
1103 if (start == NULL) start = domain;
1104 domain = string_copyn(start + 1, Ustrlen(start) - 2);
1105 }
1106
1107 /* Turn domains that look like bare IP addresses into domains in the reverse
1108 DNS. This code also deals with address literals and $sender_host_address. It's
1109 not quite kosher to treat bare domains such as EHLO 192.0.2.57 the same as
1110 address literals, but it's probably the most friendly thing to do. This is an
1111 extension to CSA, so we allow it to be turned off for proper conformance. */
1112
1113 if (string_is_ip_address(domain, NULL))
1114 {
1115 if (!dns_csa_use_reverse) return CSA_UNKNOWN;
1116 dns_build_reverse(domain, target);
1117 domain = target;
1118 }
1119
1120 /* Find out if we've already done the CSA check for this domain. If we have,
1121 return the same result again. Otherwise build a new cached result structure
1122 for this domain. The name is filled in now, and the value is filled in when
1123 we return from this function. */
1124
1125 t = tree_search(csa_cache, domain);
1126 if (t != NULL) return t->data.val;
1127
1128 t = store_get_perm(sizeof(tree_node) + Ustrlen(domain));
1129 Ustrcpy(t->name, domain);
1130 (void)tree_insertnode(&csa_cache, t);
1131
1132 /* Now we are ready to do the actual DNS lookup(s). */
1133
1134 switch (dns_special_lookup(&dnsa, domain, T_CSA, &found))
1135 {
1136 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1137
1138 default:
1139 return t->data.val = CSA_DEFER_SRV;
1140
1141 /* If we found nothing, the client's authorization is unknown. */
1142
1143 case DNS_NOMATCH:
1144 case DNS_NODATA:
1145 return t->data.val = CSA_UNKNOWN;
1146
1147 /* We got something! Go on to look at the reply in more detail. */
1148
1149 case DNS_SUCCEED:
1150 break;
1151 }
1152
1153 /* Scan the reply for well-formed CSA SRV records. */
1154
1155 for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS);
1156 rr != NULL;
1157 rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT))
1158 {
1159 if (rr->type != T_SRV) continue;
1160
1161 /* Extract the numerical SRV fields (p is incremented) */
1162
1163 p = rr->data;
1164 GETSHORT(priority, p);
1165 GETSHORT(weight, p);
1166 GETSHORT(port, p);
1167
1168 DEBUG(D_acl)
1169 debug_printf("CSA priority=%d weight=%d port=%d\n", priority, weight, port);
1170
1171 /* Check the CSA version number */
1172
1173 if (priority != 1) continue;
1174
1175 /* If the domain does not have a CSA SRV record of its own (i.e. the domain
1176 found by dns_special_lookup() is a parent of the one we asked for), we check
1177 the subdomain assertions in the port field. At the moment there's only one
1178 assertion: legitimate SMTP clients are all explicitly authorized with CSA
1179 SRV records of their own. */
1180
1181 if (found != domain)
1182 {
1183 if (port & 1)
1184 return t->data.val = CSA_FAIL_EXPLICIT;
1185 else
1186 return t->data.val = CSA_UNKNOWN;
1187 }
1188
1189 /* This CSA SRV record refers directly to our domain, so we check the value
1190 in the weight field to work out the domain's authorization. 0 and 1 are
1191 unauthorized; 3 means the client is authorized but we can't check the IP
1192 address in order to authenticate it, so we treat it as unknown; values
1193 greater than 3 are undefined. */
1194
1195 if (weight < 2) return t->data.val = CSA_FAIL_DOMAIN;
1196
1197 if (weight > 2) continue;
1198
1199 /* Weight == 2, which means the domain is authorized. We must check that the
1200 client's IP address is listed as one of the SRV target addresses. Save the
1201 target hostname then break to scan the additional data for its addresses. */
1202
1203 (void)dn_expand(dnsa.answer, dnsa.answer + dnsa.answerlen, p,
1204 (DN_EXPAND_ARG4_TYPE)target, sizeof(target));
1205
1206 DEBUG(D_acl) debug_printf("CSA target is %s\n", target);
1207
1208 break;
1209 }
1210
1211 /* If we didn't break the loop then no appropriate records were found. */
1212
1213 if (rr == NULL) return t->data.val = CSA_UNKNOWN;
1214
1215 /* Do not check addresses if the target is ".", in accordance with RFC 2782.
1216 A target of "." indicates there are no valid addresses, so the client cannot
1217 be authorized. (This is an odd configuration because weight=2 target=. is
1218 equivalent to weight=1, but we check for it in order to keep load off the
1219 root name servers.) Note that dn_expand() turns "." into "". */
1220
1221 if (Ustrcmp(target, "") == 0) return t->data.val = CSA_FAIL_NOADDR;
1222
1223 /* Scan the additional section of the CSA SRV reply for addresses belonging
1224 to the target. If the name server didn't return any additional data (e.g.
1225 because it does not fully support SRV records), we need to do another lookup
1226 to obtain the target addresses; otherwise we have a definitive result. */
1227
1228 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ADDITIONAL, target);
1229 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1230
1231 /* The DNS lookup type corresponds to the IP version used by the client. */
1232
1233 #if HAVE_IPV6
1234 if (Ustrchr(sender_host_address, ':') != NULL)
1235 type = T_AAAA;
1236 else
1237 #endif /* HAVE_IPV6 */
1238 type = T_A;
1239
1240
1241 #if HAVE_IPV6 && defined(SUPPORT_A6)
1242 DNS_LOOKUP_AGAIN:
1243 #endif
1244
1245 switch (dns_lookup(&dnsa, target, type, NULL))
1246 {
1247 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1248
1249 default:
1250 return t->data.val = CSA_DEFER_ADDR;
1251
1252 /* If the query succeeded, scan the addresses and return the result. */
1253
1254 case DNS_SUCCEED:
1255 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ANSWERS, target);
1256 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1257 /* else fall through */
1258
1259 /* If the target has no IP addresses, the client cannot have an authorized
1260 IP address. However, if the target site uses A6 records (not AAAA records)
1261 we have to do yet another lookup in order to check them. */
1262
1263 case DNS_NOMATCH:
1264 case DNS_NODATA:
1265
1266 #if HAVE_IPV6 && defined(SUPPORT_A6)
1267 if (type == T_AAAA) { type = T_A6; goto DNS_LOOKUP_AGAIN; }
1268 #endif
1269
1270 return t->data.val = CSA_FAIL_NOADDR;
1271 }
1272 }
1273
1274
1275
1276 /*************************************************
1277 * Handle verification (address & other) *
1278 *************************************************/
1279
1280 /* This function implements the "verify" condition. It is called when
1281 encountered in any ACL, because some tests are almost always permitted. Some
1282 just don't make sense, and always fail (for example, an attempt to test a host
1283 lookup for a non-TCP/IP message). Others are restricted to certain ACLs.
1284
1285 Arguments:
1286 where where called from
1287 addr the recipient address that the ACL is handling, or NULL
1288 arg the argument of "verify"
1289 user_msgptr pointer for user message
1290 log_msgptr pointer for log message
1291 basic_errno where to put verify errno
1292
1293 Returns: OK verification condition succeeded
1294 FAIL verification failed
1295 DEFER there was a problem verifying
1296 ERROR syntax error
1297 */
1298
1299 static int
1300 acl_verify(int where, address_item *addr, uschar *arg,
1301 uschar **user_msgptr, uschar **log_msgptr, int *basic_errno)
1302 {
1303 int sep = '/';
1304 int callout = -1;
1305 int callout_overall = -1;
1306 int callout_connect = -1;
1307 int verify_options = 0;
1308 int rc;
1309 BOOL verify_header_sender = FALSE;
1310 BOOL defer_ok = FALSE;
1311 BOOL callout_defer_ok = FALSE;
1312 BOOL no_details = FALSE;
1313 address_item *sender_vaddr = NULL;
1314 uschar *verify_sender_address = NULL;
1315 uschar *pm_mailfrom = NULL;
1316 uschar *se_mailfrom = NULL;
1317
1318 /* Some of the verify items have slash-separated options; some do not. Diagnose
1319 an error if options are given for items that don't expect them. This code has
1320 now got very message. Refactoring to use a table would be a good idea one day.
1321 */
1322
1323 uschar *slash = Ustrchr(arg, '/');
1324 uschar *list = arg;
1325 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
1326
1327 if (ss == NULL) goto BAD_VERIFY;
1328
1329 /* Handle name/address consistency verification in a separate function. */
1330
1331 if (strcmpic(ss, US"reverse_host_lookup") == 0)
1332 {
1333 if (slash != NULL) goto NO_OPTIONS;
1334 if (sender_host_address == NULL) return OK;
1335 return acl_verify_reverse(user_msgptr, log_msgptr);
1336 }
1337
1338 /* TLS certificate verification is done at STARTTLS time; here we just
1339 test whether it was successful or not. (This is for optional verification; for
1340 mandatory verification, the connection doesn't last this long.) */
1341
1342 if (strcmpic(ss, US"certificate") == 0)
1343 {
1344 if (slash != NULL) goto NO_OPTIONS;
1345 if (tls_certificate_verified) return OK;
1346 *user_msgptr = US"no verified certificate";
1347 return FAIL;
1348 }
1349
1350 /* We can test the result of optional HELO verification */
1351
1352 if (strcmpic(ss, US"helo") == 0)
1353 {
1354 if (slash != NULL) goto NO_OPTIONS;
1355 return helo_verified? OK : FAIL;
1356 }
1357
1358 /* Do Client SMTP Authorization checks in a separate function, and turn the
1359 result code into user-friendly strings. */
1360
1361 if (strcmpic(ss, US"csa") == 0)
1362 {
1363 rc = acl_verify_csa(list);
1364 *log_msgptr = *user_msgptr = string_sprintf("client SMTP authorization %s",
1365 csa_reason_string[rc]);
1366 csa_status = csa_status_string[rc];
1367 DEBUG(D_acl) debug_printf("CSA result %s\n", csa_status);
1368 return csa_return_code[rc];
1369 }
1370
1371 /* Check that all relevant header lines have the correct syntax. If there is
1372 a syntax error, we return details of the error to the sender if configured to
1373 send out full details. (But a "message" setting on the ACL can override, as
1374 always). */
1375
1376 if (strcmpic(ss, US"header_syntax") == 0)
1377 {
1378 if (slash != NULL) goto NO_OPTIONS;
1379 if (where != ACL_WHERE_DATA && where != ACL_WHERE_NOTSMTP)
1380 {
1381 *log_msgptr = string_sprintf("cannot check header contents in ACL for %s "
1382 "(only possible in ACL for DATA)", acl_wherenames[where]);
1383 return ERROR;
1384 }
1385 rc = verify_check_headers(log_msgptr);
1386 if (rc != OK && smtp_return_error_details && *log_msgptr != NULL)
1387 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1388 return rc;
1389 }
1390
1391
1392 /* The remaining verification tests check recipient and sender addresses,
1393 either from the envelope or from the header. There are a number of
1394 slash-separated options that are common to all of them. */
1395
1396
1397 /* Check that there is at least one verifiable sender address in the relevant
1398 header lines. This can be followed by callout and defer options, just like
1399 sender and recipient. */
1400
1401 if (strcmpic(ss, US"header_sender") == 0)
1402 {
1403 if (where != ACL_WHERE_DATA && where != ACL_WHERE_NOTSMTP)
1404 {
1405 *log_msgptr = string_sprintf("cannot check header contents in ACL for %s "
1406 "(only possible in ACL for DATA)", acl_wherenames[where]);
1407 return ERROR;
1408 }
1409 verify_header_sender = TRUE;
1410 }
1411
1412 /* Otherwise, first item in verify argument must be "sender" or "recipient".
1413 In the case of a sender, this can optionally be followed by an address to use
1414 in place of the actual sender (rare special-case requirement). */
1415
1416 else if (strncmpic(ss, US"sender", 6) == 0)
1417 {
1418 uschar *s = ss + 6;
1419 if (where > ACL_WHERE_NOTSMTP)
1420 {
1421 *log_msgptr = string_sprintf("cannot verify sender in ACL for %s "
1422 "(only possible for MAIL, RCPT, PREDATA, or DATA)",
1423 acl_wherenames[where]);
1424 return ERROR;
1425 }
1426 if (*s == 0)
1427 verify_sender_address = sender_address;
1428 else
1429 {
1430 while (isspace(*s)) s++;
1431 if (*s++ != '=') goto BAD_VERIFY;
1432 while (isspace(*s)) s++;
1433 verify_sender_address = string_copy(s);
1434 }
1435 }
1436 else
1437 {
1438 if (strcmpic(ss, US"recipient") != 0) goto BAD_VERIFY;
1439 if (addr == NULL)
1440 {
1441 *log_msgptr = string_sprintf("cannot verify recipient in ACL for %s "
1442 "(only possible for RCPT)", acl_wherenames[where]);
1443 return ERROR;
1444 }
1445 }
1446
1447 /* Remaining items are optional; they apply to sender and recipient
1448 verification, including "header sender" verification. */
1449
1450 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size))
1451 != NULL)
1452 {
1453 if (strcmpic(ss, US"defer_ok") == 0) defer_ok = TRUE;
1454 else if (strcmpic(ss, US"no_details") == 0) no_details = TRUE;
1455
1456 /* These two old options are left for backwards compatibility */
1457
1458 else if (strcmpic(ss, US"callout_defer_ok") == 0)
1459 {
1460 callout_defer_ok = TRUE;
1461 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1462 }
1463
1464 else if (strcmpic(ss, US"check_postmaster") == 0)
1465 {
1466 pm_mailfrom = US"";
1467 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1468 }
1469
1470 /* The callout option has a number of sub-options, comma separated */
1471
1472 else if (strncmpic(ss, US"callout", 7) == 0)
1473 {
1474 callout = CALLOUT_TIMEOUT_DEFAULT;
1475 ss += 7;
1476 if (*ss != 0)
1477 {
1478 while (isspace(*ss)) ss++;
1479 if (*ss++ == '=')
1480 {
1481 int optsep = ',';
1482 uschar *opt;
1483 uschar buffer[256];
1484 while (isspace(*ss)) ss++;
1485
1486 /* This callout option handling code has become a mess as new options
1487 have been added in an ad hoc manner. It should be tidied up into some
1488 kind of table-driven thing. */
1489
1490 while ((opt = string_nextinlist(&ss, &optsep, buffer, sizeof(buffer)))
1491 != NULL)
1492 {
1493 if (strcmpic(opt, US"defer_ok") == 0) callout_defer_ok = TRUE;
1494 else if (strcmpic(opt, US"no_cache") == 0)
1495 verify_options |= vopt_callout_no_cache;
1496 else if (strcmpic(opt, US"random") == 0)
1497 verify_options |= vopt_callout_random;
1498 else if (strcmpic(opt, US"use_sender") == 0)
1499 verify_options |= vopt_callout_recipsender;
1500 else if (strcmpic(opt, US"use_postmaster") == 0)
1501 verify_options |= vopt_callout_recippmaster;
1502 else if (strcmpic(opt, US"postmaster") == 0) pm_mailfrom = US"";
1503
1504 else if (strncmpic(opt, US"mailfrom", 8) == 0)
1505 {
1506 if (!verify_header_sender)
1507 {
1508 *log_msgptr = string_sprintf("\"mailfrom\" is allowed as a "
1509 "callout option only for verify=header_sender (detected in ACL "
1510 "condition \"%s\")", arg);
1511 return ERROR;
1512 }
1513 opt += 8;
1514 while (isspace(*opt)) opt++;
1515 if (*opt++ != '=')
1516 {
1517 *log_msgptr = string_sprintf("'=' expected after "
1518 "\"mailfrom\" in ACL condition \"%s\"", arg);
1519 return ERROR;
1520 }
1521 while (isspace(*opt)) opt++;
1522 se_mailfrom = string_copy(opt);
1523 }
1524
1525 else if (strncmpic(opt, US"postmaster_mailfrom", 19) == 0)
1526 {
1527 opt += 19;
1528 while (isspace(*opt)) opt++;
1529 if (*opt++ != '=')
1530 {
1531 *log_msgptr = string_sprintf("'=' expected after "
1532 "\"postmaster_mailfrom\" in ACL condition \"%s\"", arg);
1533 return ERROR;
1534 }
1535 while (isspace(*opt)) opt++;
1536 pm_mailfrom = string_copy(opt);
1537 }
1538
1539 else if (strncmpic(opt, US"maxwait", 7) == 0)
1540 {
1541 opt += 7;
1542 while (isspace(*opt)) opt++;
1543 if (*opt++ != '=')
1544 {
1545 *log_msgptr = string_sprintf("'=' expected after \"maxwait\" in "
1546 "ACL condition \"%s\"", arg);
1547 return ERROR;
1548 }
1549 while (isspace(*opt)) opt++;
1550 callout_overall = readconf_readtime(opt, 0, FALSE);
1551 if (callout_overall < 0)
1552 {
1553 *log_msgptr = string_sprintf("bad time value in ACL condition "
1554 "\"verify %s\"", arg);
1555 return ERROR;
1556 }
1557 }
1558 else if (strncmpic(opt, US"connect", 7) == 0)
1559 {
1560 opt += 7;
1561 while (isspace(*opt)) opt++;
1562 if (*opt++ != '=')
1563 {
1564 *log_msgptr = string_sprintf("'=' expected after "
1565 "\"callout_overaall\" in ACL condition \"%s\"", arg);
1566 return ERROR;
1567 }
1568 while (isspace(*opt)) opt++;
1569 callout_connect = readconf_readtime(opt, 0, FALSE);
1570 if (callout_connect < 0)
1571 {
1572 *log_msgptr = string_sprintf("bad time value in ACL condition "
1573 "\"verify %s\"", arg);
1574 return ERROR;
1575 }
1576 }
1577 else /* Plain time is callout connect/command timeout */
1578 {
1579 callout = readconf_readtime(opt, 0, FALSE);
1580 if (callout < 0)
1581 {
1582 *log_msgptr = string_sprintf("bad time value in ACL condition "
1583 "\"verify %s\"", arg);
1584 return ERROR;
1585 }
1586 }
1587 }
1588 }
1589 else
1590 {
1591 *log_msgptr = string_sprintf("'=' expected after \"callout\" in "
1592 "ACL condition \"%s\"", arg);
1593 return ERROR;
1594 }
1595 }
1596 }
1597
1598 /* Option not recognized */
1599
1600 else
1601 {
1602 *log_msgptr = string_sprintf("unknown option \"%s\" in ACL "
1603 "condition \"verify %s\"", ss, arg);
1604 return ERROR;
1605 }
1606 }
1607
1608 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster)) ==
1609 (vopt_callout_recipsender|vopt_callout_recippmaster))
1610 {
1611 *log_msgptr = US"only one of use_sender and use_postmaster can be set "
1612 "for a recipient callout";
1613 return ERROR;
1614 }
1615
1616 /* Handle sender-in-header verification. Default the user message to the log
1617 message if giving out verification details. */
1618
1619 if (verify_header_sender)
1620 {
1621 int verrno;
1622 rc = verify_check_header_address(user_msgptr, log_msgptr, callout,
1623 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, verify_options,
1624 &verrno);
1625 if (rc != OK)
1626 {
1627 *basic_errno = verrno;
1628 if (smtp_return_error_details)
1629 {
1630 if (*user_msgptr == NULL && *log_msgptr != NULL)
1631 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1632 if (rc == DEFER) acl_temp_details = TRUE;
1633 }
1634 }
1635 }
1636
1637 /* Handle a sender address. The default is to verify *the* sender address, but
1638 optionally a different address can be given, for special requirements. If the
1639 address is empty, we are dealing with a bounce message that has no sender, so
1640 we cannot do any checking. If the real sender address gets rewritten during
1641 verification (e.g. DNS widening), set the flag to stop it being rewritten again
1642 during message reception.
1643
1644 A list of verified "sender" addresses is kept to try to avoid doing to much
1645 work repetitively when there are multiple recipients in a message and they all
1646 require sender verification. However, when callouts are involved, it gets too
1647 complicated because different recipients may require different callout options.
1648 Therefore, we always do a full sender verify when any kind of callout is
1649 specified. Caching elsewhere, for instance in the DNS resolver and in the
1650 callout handling, should ensure that this is not terribly inefficient. */
1651
1652 else if (verify_sender_address != NULL)
1653 {
1654 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster))
1655 != 0)
1656 {
1657 *log_msgptr = US"use_sender or use_postmaster cannot be used for a "
1658 "sender verify callout";
1659 return ERROR;
1660 }
1661
1662 sender_vaddr = verify_checked_sender(verify_sender_address);
1663 if (sender_vaddr != NULL && /* Previously checked */
1664 callout <= 0) /* No callout needed this time */
1665 {
1666 /* If the "routed" flag is set, it means that routing worked before, so
1667 this check can give OK (the saved return code value, if set, belongs to a
1668 callout that was done previously). If the "routed" flag is not set, routing
1669 must have failed, so we use the saved return code. */
1670
1671 if (testflag(sender_vaddr, af_verify_routed)) rc = OK; else
1672 {
1673 rc = sender_vaddr->special_action;
1674 *basic_errno = sender_vaddr->basic_errno;
1675 }
1676 HDEBUG(D_acl) debug_printf("using cached sender verify result\n");
1677 }
1678
1679 /* Do a new verification, and cache the result. The cache is used to avoid
1680 verifying the sender multiple times for multiple RCPTs when callouts are not
1681 specified (see comments above).
1682
1683 The cache is also used on failure to give details in response to the first
1684 RCPT that gets bounced for this reason. However, this can be suppressed by
1685 the no_details option, which sets the flag that says "this detail has already
1686 been sent". The cache normally contains just one address, but there may be
1687 more in esoteric circumstances. */
1688
1689 else
1690 {
1691 BOOL routed = TRUE;
1692 uschar *save_address_data = deliver_address_data;
1693
1694 sender_vaddr = deliver_make_addr(verify_sender_address, TRUE);
1695 if (no_details) setflag(sender_vaddr, af_sverify_told);
1696 if (verify_sender_address[0] != 0)
1697 {
1698 /* If this is the real sender address, save the unrewritten version
1699 for use later in receive. Otherwise, set a flag so that rewriting the
1700 sender in verify_address() does not update sender_address. */
1701
1702 if (verify_sender_address == sender_address)
1703 sender_address_unrewritten = sender_address;
1704 else
1705 verify_options |= vopt_fake_sender;
1706
1707 /* The recipient, qualify, and expn options are never set in
1708 verify_options. */
1709
1710 rc = verify_address(sender_vaddr, NULL, verify_options, callout,
1711 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, &routed);
1712
1713 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
1714
1715 if (rc == OK)
1716 {
1717 if (Ustrcmp(sender_vaddr->address, verify_sender_address) != 0)
1718 {
1719 DEBUG(D_acl) debug_printf("sender %s verified ok as %s\n",
1720 verify_sender_address, sender_vaddr->address);
1721 }
1722 else
1723 {
1724 DEBUG(D_acl) debug_printf("sender %s verified ok\n",
1725 verify_sender_address);
1726 }
1727 }
1728 else *basic_errno = sender_vaddr->basic_errno;
1729 }
1730 else rc = OK; /* Null sender */
1731
1732 /* Cache the result code */
1733
1734 if (routed) setflag(sender_vaddr, af_verify_routed);
1735 if (callout > 0) setflag(sender_vaddr, af_verify_callout);
1736 sender_vaddr->special_action = rc;
1737 sender_vaddr->next = sender_verified_list;
1738 sender_verified_list = sender_vaddr;
1739
1740 /* Restore the recipient address data, which might have been clobbered by
1741 the sender verification. */
1742
1743 deliver_address_data = save_address_data;
1744 }
1745
1746 /* Put the sender address_data value into $sender_address_data */
1747
1748 sender_address_data = sender_vaddr->p.address_data;
1749 }
1750
1751 /* A recipient address just gets a straightforward verify; again we must handle
1752 the DEFER overrides. */
1753
1754 else
1755 {
1756 address_item addr2;
1757
1758 /* We must use a copy of the address for verification, because it might
1759 get rewritten. */
1760
1761 addr2 = *addr;
1762 rc = verify_address(&addr2, NULL, verify_options|vopt_is_recipient, callout,
1763 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, NULL);
1764 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
1765
1766 *log_msgptr = addr2.message;
1767 *user_msgptr = (addr2.user_message != NULL)?
1768 addr2.user_message : addr2.message;
1769 *basic_errno = addr2.basic_errno;
1770
1771 /* Make $address_data visible */
1772 deliver_address_data = addr2.p.address_data;
1773 }
1774
1775 /* We have a result from the relevant test. Handle defer overrides first. */
1776
1777 if (rc == DEFER && (defer_ok ||
1778 (callout_defer_ok && *basic_errno == ERRNO_CALLOUTDEFER)))
1779 {
1780 HDEBUG(D_acl) debug_printf("verify defer overridden by %s\n",
1781 defer_ok? "defer_ok" : "callout_defer_ok");
1782 rc = OK;
1783 }
1784
1785 /* If we've failed a sender, set up a recipient message, and point
1786 sender_verified_failed to the address item that actually failed. */
1787
1788 if (rc != OK && verify_sender_address != NULL)
1789 {
1790 if (rc != DEFER)
1791 {
1792 *log_msgptr = *user_msgptr = US"Sender verify failed";
1793 }
1794 else if (*basic_errno != ERRNO_CALLOUTDEFER)
1795 {
1796 *log_msgptr = *user_msgptr = US"Could not complete sender verify";
1797 }
1798 else
1799 {
1800 *log_msgptr = US"Could not complete sender verify callout";
1801 *user_msgptr = smtp_return_error_details? sender_vaddr->user_message :
1802 *log_msgptr;
1803 }
1804
1805 sender_verified_failed = sender_vaddr;
1806 }
1807
1808 /* Verifying an address messes up the values of $domain and $local_part,
1809 so reset them before returning if this is a RCPT ACL. */
1810
1811 if (addr != NULL)
1812 {
1813 deliver_domain = addr->domain;
1814 deliver_localpart = addr->local_part;
1815 }
1816 return rc;
1817
1818 /* Syntax errors in the verify argument come here. */
1819
1820 BAD_VERIFY:
1821 *log_msgptr = string_sprintf("expected \"sender[=address]\", \"recipient\", "
1822 "\"helo\", \"header_syntax\", \"header_sender\" or "
1823 "\"reverse_host_lookup\" at start of ACL condition "
1824 "\"verify %s\"", arg);
1825 return ERROR;
1826
1827 /* Options supplied when not allowed come here */
1828
1829 NO_OPTIONS:
1830 *log_msgptr = string_sprintf("unexpected '/' found in \"%s\" "
1831 "(this verify item has no options)", arg);
1832 return ERROR;
1833 }
1834
1835
1836
1837
1838 /*************************************************
1839 * Check argument for control= modifier *
1840 *************************************************/
1841
1842 /* Called from acl_check_condition() below
1843
1844 Arguments:
1845 arg the argument string for control=
1846 pptr set to point to the terminating character
1847 where which ACL we are in
1848 log_msgptr for error messages
1849
1850 Returns: CONTROL_xxx value
1851 */
1852
1853 static int
1854 decode_control(uschar *arg, uschar **pptr, int where, uschar **log_msgptr)
1855 {
1856 int len;
1857 control_def *d;
1858
1859 for (d = controls_list;
1860 d < controls_list + sizeof(controls_list)/sizeof(control_def);
1861 d++)
1862 {
1863 len = Ustrlen(d->name);
1864 if (Ustrncmp(d->name, arg, len) == 0) break;
1865 }
1866
1867 if (d >= controls_list + sizeof(controls_list)/sizeof(control_def) ||
1868 (arg[len] != 0 && (!d->has_option || arg[len] != '/')))
1869 {
1870 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
1871 return CONTROL_ERROR;
1872 }
1873
1874 *pptr = arg + len;
1875 return d->value;
1876 }
1877
1878
1879
1880 /*************************************************
1881 * Handle conditions/modifiers on an ACL item *
1882 *************************************************/
1883
1884 /* Called from acl_check() below.
1885
1886 Arguments:
1887 verb ACL verb
1888 cb ACL condition block - if NULL, result is OK
1889 where where called from
1890 addr the address being checked for RCPT, or NULL
1891 level the nesting level
1892 epp pointer to pass back TRUE if "endpass" encountered
1893 (applies only to "accept" and "discard")
1894 user_msgptr user message pointer
1895 log_msgptr log message pointer
1896 basic_errno pointer to where to put verify error
1897
1898 Returns: OK - all conditions are met
1899 DISCARD - an "acl" condition returned DISCARD - only allowed
1900 for "accept" or "discard" verbs
1901 FAIL - at least one condition fails
1902 FAIL_DROP - an "acl" condition returned FAIL_DROP
1903 DEFER - can't tell at the moment (typically, lookup defer,
1904 but can be temporary callout problem)
1905 ERROR - ERROR from nested ACL or expansion failure or other
1906 error
1907 */
1908
1909 static int
1910 acl_check_condition(int verb, acl_condition_block *cb, int where,
1911 address_item *addr, int level, BOOL *epp, uschar **user_msgptr,
1912 uschar **log_msgptr, int *basic_errno)
1913 {
1914 uschar *user_message = NULL;
1915 uschar *log_message = NULL;
1916 uschar *p;
1917 int rc = OK;
1918 #ifdef WITH_CONTENT_SCAN
1919 int sep = '/';
1920 #endif
1921
1922 for (; cb != NULL; cb = cb->next)
1923 {
1924 uschar *arg;
1925 int control_type;
1926
1927 /* The message and log_message items set up messages to be used in
1928 case of rejection. They are expanded later. */
1929
1930 if (cb->type == ACLC_MESSAGE)
1931 {
1932 user_message = cb->arg;
1933 continue;
1934 }
1935
1936 if (cb->type == ACLC_LOG_MESSAGE)
1937 {
1938 log_message = cb->arg;
1939 continue;
1940 }
1941
1942 /* The endpass "condition" just sets a flag to show it occurred. This is
1943 checked at compile time to be on an "accept" or "discard" item. */
1944
1945 if (cb->type == ACLC_ENDPASS)
1946 {
1947 *epp = TRUE;
1948 continue;
1949 }
1950
1951 /* For other conditions and modifiers, the argument is expanded now for some
1952 of them, but not for all, because expansion happens down in some lower level
1953 checking functions in some cases. */
1954
1955 if (cond_expand_at_top[cb->type])
1956 {
1957 arg = expand_string(cb->arg);
1958 if (arg == NULL)
1959 {
1960 if (expand_string_forcedfail) continue;
1961 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s",
1962 cb->arg, expand_string_message);
1963 return search_find_defer? DEFER : ERROR;
1964 }
1965 }
1966 else arg = cb->arg;
1967
1968 /* Show condition, and expanded condition if it's different */
1969
1970 HDEBUG(D_acl)
1971 {
1972 int lhswidth = 0;
1973 debug_printf("check %s%s %n",
1974 (!cond_modifiers[cb->type] && cb->u.negated)? "!":"",
1975 conditions[cb->type], &lhswidth);
1976
1977 if (cb->type == ACLC_SET)
1978 {
1979 int n = cb->u.varnumber;
1980 int t = (n < ACL_C_MAX)? 'c' : 'm';
1981 if (n >= ACL_C_MAX) n -= ACL_C_MAX;
1982 debug_printf("acl_%c%d ", t, n);
1983 lhswidth += 7;
1984 }
1985
1986 debug_printf("= %s\n", cb->arg);
1987
1988 if (arg != cb->arg)
1989 debug_printf("%.*s= %s\n", lhswidth,
1990 US" ", CS arg);
1991 }
1992
1993 /* Check that this condition makes sense at this time */
1994
1995 if ((cond_forbids[cb->type] & (1 << where)) != 0)
1996 {
1997 *log_msgptr = string_sprintf("cannot %s %s condition in %s ACL",
1998 cond_modifiers[cb->type]? "use" : "test",
1999 conditions[cb->type], acl_wherenames[where]);
2000 return ERROR;
2001 }
2002
2003 /* Run the appropriate test for each condition, or take the appropriate
2004 action for the remaining modifiers. */
2005
2006 switch(cb->type)
2007 {
2008 /* A nested ACL that returns "discard" makes sense only for an "accept" or
2009 "discard" verb. */
2010
2011 case ACLC_ACL:
2012 rc = acl_check_internal(where, addr, arg, level+1, user_msgptr, log_msgptr);
2013 if (rc == DISCARD && verb != ACL_ACCEPT && verb != ACL_DISCARD)
2014 {
2015 *log_msgptr = string_sprintf("nested ACL returned \"discard\" for "
2016 "\"%s\" command (only allowed with \"accept\" or \"discard\")",
2017 verbs[verb]);
2018 return ERROR;
2019 }
2020 break;
2021
2022 case ACLC_AUTHENTICATED:
2023 rc = (sender_host_authenticated == NULL)? FAIL :
2024 match_isinlist(sender_host_authenticated, &arg, 0, NULL, NULL, MCL_STRING,
2025 TRUE, NULL);
2026 break;
2027
2028 #ifdef EXPERIMENTAL_BRIGHTMAIL
2029 case ACLC_BMI_OPTIN:
2030 {
2031 int old_pool = store_pool;
2032 store_pool = POOL_PERM;
2033 bmi_current_optin = string_copy(arg);
2034 store_pool = old_pool;
2035 }
2036 break;
2037 #endif
2038
2039 case ACLC_CONDITION:
2040 if (Ustrspn(arg, "0123456789") == Ustrlen(arg)) /* Digits, or empty */
2041 rc = (Uatoi(arg) == 0)? FAIL : OK;
2042 else
2043 rc = (strcmpic(arg, US"no") == 0 ||
2044 strcmpic(arg, US"false") == 0)? FAIL :
2045 (strcmpic(arg, US"yes") == 0 ||
2046 strcmpic(arg, US"true") == 0)? OK : DEFER;
2047 if (rc == DEFER)
2048 *log_msgptr = string_sprintf("invalid \"condition\" value \"%s\"", arg);
2049 break;
2050
2051 case ACLC_CONTROL:
2052 control_type = decode_control(arg, &p, where, log_msgptr);
2053
2054 /* Check if this control makes sense at this time */
2055
2056 if ((control_forbids[control_type] & (1 << where)) != 0)
2057 {
2058 *log_msgptr = string_sprintf("cannot use \"control=%s\" in %s ACL",
2059 controls[control_type], acl_wherenames[where]);
2060 return ERROR;
2061 }
2062
2063 switch(control_type)
2064 {
2065 #ifdef EXPERIMENTAL_BRIGHTMAIL
2066 case CONTROL_BMI_RUN:
2067 bmi_run = 1;
2068 break;
2069 #endif
2070 #ifdef EXPERIMENTAL_DOMAINKEYS
2071 case CONTROL_DK_VERIFY:
2072 dk_do_verify = 1;
2073 break;
2074 #endif
2075 case CONTROL_ERROR:
2076 return ERROR;
2077
2078 case CONTROL_CASEFUL_LOCAL_PART:
2079 deliver_localpart = addr->cc_local_part;
2080 break;
2081
2082 case CONTROL_CASELOWER_LOCAL_PART:
2083 deliver_localpart = addr->lc_local_part;
2084 break;
2085
2086 case CONTROL_ENFORCE_SYNC:
2087 smtp_enforce_sync = TRUE;
2088 break;
2089
2090 case CONTROL_NO_ENFORCE_SYNC:
2091 smtp_enforce_sync = FALSE;
2092 break;
2093
2094 #ifdef WITH_CONTENT_SCAN
2095 case CONTROL_NO_MBOX_UNSPOOL:
2096 no_mbox_unspool = TRUE;
2097 break;
2098 #endif
2099
2100 case CONTROL_NO_MULTILINE:
2101 no_multiline_responses = TRUE;
2102 break;
2103
2104 case CONTROL_FAKEREJECT:
2105 fake_reject = TRUE;
2106 if (*p == '/')
2107 {
2108 uschar *pp = p + 1;
2109 while (*pp != 0) pp++;
2110 fake_reject_text = expand_string(string_copyn(p+1, pp-p));
2111 p = pp;
2112 }
2113 else
2114 {
2115 /* Explicitly reset to default string */
2116 fake_reject_text = US"Your message has been rejected but is being kept for evaluation.\nIf it was a legitimate message, it may still be delivered to the target recipient(s).";
2117 }
2118 break;
2119
2120 case CONTROL_FREEZE:
2121 deliver_freeze = TRUE;
2122 deliver_frozen_at = time(NULL);
2123 break;
2124
2125 case CONTROL_QUEUE_ONLY:
2126 queue_only_policy = TRUE;
2127 break;
2128
2129 case CONTROL_SUBMISSION:
2130 submission_mode = TRUE;
2131 while (*p == '/')
2132 {
2133 if (Ustrncmp(p, "/sender_retain", 14) == 0)
2134 {
2135 p += 14;
2136 active_local_sender_retain = TRUE;
2137 active_local_from_check = FALSE;
2138 }
2139 else if (Ustrncmp(p, "/domain=", 8) == 0)
2140 {
2141 uschar *pp = p + 8;
2142 while (*pp != 0 && *pp != '/') pp++;
2143 submission_domain = string_copyn(p+8, pp-p);
2144 p = pp;
2145 }
2146 else break;
2147 }
2148 if (*p != 0)
2149 {
2150 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
2151 return ERROR;
2152 }
2153 break;
2154 }
2155 break;
2156
2157 #ifdef WITH_CONTENT_SCAN
2158 case ACLC_DECODE:
2159 rc = mime_decode(&arg);
2160 break;
2161 #endif
2162
2163 case ACLC_DELAY:
2164 {
2165 int delay = readconf_readtime(arg, 0, FALSE);
2166 if (delay < 0)
2167 {
2168 *log_msgptr = string_sprintf("syntax error in argument for \"delay\" "
2169 "modifier: \"%s\" is not a time value", arg);
2170 return ERROR;
2171 }
2172 else
2173 {
2174 HDEBUG(D_acl) debug_printf("delay modifier requests %d-second delay\n",
2175 delay);
2176 if (host_checking)
2177 {
2178 HDEBUG(D_acl)
2179 debug_printf("delay skipped in -bh checking mode\n");
2180 }
2181
2182 /* It appears to be impossible to detect that a TCP/IP connection has
2183 gone away without reading from it. This means that we cannot shorten
2184 the delay below if the client goes away, because we cannot discover
2185 that the client has closed its end of the connection. (The connection
2186 is actually in a half-closed state, waiting for the server to close its
2187 end.) It would be nice to be able to detect this state, so that the
2188 Exim process is not held up unnecessarily. However, it seems that we
2189 can't. The poll() function does not do the right thing, and in any case
2190 it is not always available.
2191
2192 NOTE: If ever this state of affairs changes, remember that we may be
2193 dealing with stdin/stdout here, in addition to TCP/IP connections.
2194 Whatever is done must work in both cases. To detected the stdin/stdout
2195 case, check for smtp_in or smtp_out being NULL. */
2196
2197 else
2198 {
2199 while (delay > 0) delay = sleep(delay);
2200 }
2201 }
2202 }
2203 break;
2204
2205 #ifdef WITH_OLD_DEMIME
2206 case ACLC_DEMIME:
2207 rc = demime(&arg);
2208 break;
2209 #endif
2210
2211 #ifdef EXPERIMENTAL_DOMAINKEYS
2212 case ACLC_DK_DOMAIN_SOURCE:
2213 if (dk_verify_block == NULL) { rc = FAIL; break; };
2214 /* check header source of domain against given string */
2215 switch (dk_verify_block->address_source) {
2216 case DK_EXIM_ADDRESS_FROM_FROM:
2217 rc = match_isinlist(US"from", &arg, 0, NULL,
2218 NULL, MCL_STRING, TRUE, NULL);
2219 break;
2220 case DK_EXIM_ADDRESS_FROM_SENDER:
2221 rc = match_isinlist(US"sender", &arg, 0, NULL,
2222 NULL, MCL_STRING, TRUE, NULL);
2223 break;
2224 case DK_EXIM_ADDRESS_NONE:
2225 rc = match_isinlist(US"none", &arg, 0, NULL,
2226 NULL, MCL_STRING, TRUE, NULL);
2227 break;
2228 }
2229 break;
2230 case ACLC_DK_POLICY:
2231 if (dk_verify_block == NULL) { rc = FAIL; break; };
2232 /* check policy against given string, default FAIL */
2233 rc = FAIL;
2234 if (dk_verify_block->signsall)
2235 rc = match_isinlist(US"signsall", &arg, 0, NULL,
2236 NULL, MCL_STRING, TRUE, NULL);
2237 if (dk_verify_block->testing)
2238 rc = match_isinlist(US"testing", &arg, 0, NULL,
2239 NULL, MCL_STRING, TRUE, NULL);
2240 break;
2241 case ACLC_DK_SENDER_DOMAINS:
2242 if (dk_verify_block == NULL) { rc = FAIL; break; };
2243 if (dk_verify_block->domain != NULL)
2244 rc = match_isinlist(dk_verify_block->domain, &arg, 0, &domainlist_anchor,
2245 NULL, MCL_DOMAIN, TRUE, NULL);
2246 else rc = FAIL;
2247 break;
2248 case ACLC_DK_SENDER_LOCAL_PARTS:
2249 if (dk_verify_block == NULL) { rc = FAIL; break; };
2250 if (dk_verify_block->local_part != NULL)
2251 rc = match_isinlist(dk_verify_block->local_part, &arg, 0, &localpartlist_anchor,
2252 NULL, MCL_LOCALPART, TRUE, NULL);
2253 else rc = FAIL;
2254 break;
2255 case ACLC_DK_SENDERS:
2256 if (dk_verify_block == NULL) { rc = FAIL; break; };
2257 if (dk_verify_block->address != NULL)
2258 rc = match_address_list(dk_verify_block->address, TRUE, TRUE, &arg, NULL, -1, 0, NULL);
2259 else rc = FAIL;
2260 break;
2261 case ACLC_DK_STATUS:
2262 if (dk_verify_block == NULL) { rc = FAIL; break; };
2263 if (dk_verify_block->result > 0) {
2264 switch(dk_verify_block->result) {
2265 case DK_EXIM_RESULT_BAD_FORMAT:
2266 rc = match_isinlist(US"bad format", &arg, 0, NULL,
2267 NULL, MCL_STRING, TRUE, NULL);
2268 break;
2269 case DK_EXIM_RESULT_NO_KEY:
2270 rc = match_isinlist(US"no key", &arg, 0, NULL,
2271 NULL, MCL_STRING, TRUE, NULL);
2272 break;
2273 case DK_EXIM_RESULT_NO_SIGNATURE:
2274 rc = match_isinlist(US"no signature", &arg, 0, NULL,
2275 NULL, MCL_STRING, TRUE, NULL);
2276 break;
2277 case DK_EXIM_RESULT_REVOKED:
2278 rc = match_isinlist(US"revoked", &arg, 0, NULL,
2279 NULL, MCL_STRING, TRUE, NULL);
2280 break;
2281 case DK_EXIM_RESULT_NON_PARTICIPANT:
2282 rc = match_isinlist(US"non-participant", &arg, 0, NULL,
2283 NULL, MCL_STRING, TRUE, NULL);
2284 break;
2285 case DK_EXIM_RESULT_GOOD:
2286 rc = match_isinlist(US"good", &arg, 0, NULL,
2287 NULL, MCL_STRING, TRUE, NULL);
2288 break;
2289 case DK_EXIM_RESULT_BAD:
2290 rc = match_isinlist(US"bad", &arg, 0, NULL,
2291 NULL, MCL_STRING, TRUE, NULL);
2292 break;
2293 }
2294 }
2295 break;
2296 #endif
2297
2298 case ACLC_DNSLISTS:
2299 rc = verify_check_dnsbl(&arg);
2300 break;
2301
2302 case ACLC_DOMAINS:
2303 rc = match_isinlist(addr->domain, &arg, 0, &domainlist_anchor,
2304 addr->domain_cache, MCL_DOMAIN, TRUE, &deliver_domain_data);
2305 break;
2306
2307 /* The value in tls_cipher is the full cipher name, for example,
2308 TLSv1:DES-CBC3-SHA:168, whereas the values to test for are just the
2309 cipher names such as DES-CBC3-SHA. But program defensively. We don't know
2310 what may in practice come out of the SSL library - which at the time of
2311 writing is poorly documented. */
2312
2313 case ACLC_ENCRYPTED:
2314 if (tls_cipher == NULL) rc = FAIL; else
2315 {
2316 uschar *endcipher = NULL;
2317 uschar *cipher = Ustrchr(tls_cipher, ':');
2318 if (cipher == NULL) cipher = tls_cipher; else
2319 {
2320 endcipher = Ustrchr(++cipher, ':');
2321 if (endcipher != NULL) *endcipher = 0;
2322 }
2323 rc = match_isinlist(cipher, &arg, 0, NULL, NULL, MCL_STRING, TRUE, NULL);
2324 if (endcipher != NULL) *endcipher = ':';
2325 }
2326 break;
2327
2328 /* Use verify_check_this_host() instead of verify_check_host() so that
2329 we can pass over &host_data to catch any looked up data. Once it has been
2330 set, it retains its value so that it's still there if another ACL verb
2331 comes through here and uses the cache. However, we must put it into
2332 permanent store in case it is also expected to be used in a subsequent
2333 message in the same SMTP connection. */
2334
2335 case ACLC_HOSTS:
2336 rc = verify_check_this_host(&arg, sender_host_cache, NULL,
2337 (sender_host_address == NULL)? US"" : sender_host_address, &host_data);
2338 if (host_data != NULL) host_data = string_copy_malloc(host_data);
2339 break;
2340
2341 case ACLC_LOCAL_PARTS:
2342 rc = match_isinlist(addr->cc_local_part, &arg, 0,
2343 &localpartlist_anchor, addr->localpart_cache, MCL_LOCALPART, TRUE,
2344 &deliver_localpart_data);
2345 break;
2346
2347 case ACLC_LOGWRITE:
2348 {
2349 int logbits = 0;
2350 uschar *s = arg;
2351 if (*s == ':')
2352 {
2353 s++;
2354 while (*s != ':')
2355 {
2356 if (Ustrncmp(s, "main", 4) == 0)
2357 { logbits |= LOG_MAIN; s += 4; }
2358 else if (Ustrncmp(s, "panic", 5) == 0)
2359 { logbits |= LOG_PANIC; s += 5; }
2360 else if (Ustrncmp(s, "reject", 6) == 0)
2361 { logbits |= LOG_REJECT; s += 6; }
2362 else
2363 {
2364 logbits = LOG_MAIN|LOG_PANIC;
2365 s = string_sprintf(":unknown log name in \"%s\" in "
2366 "\"logwrite\" in %s ACL", arg, acl_wherenames[where]);
2367 }
2368 if (*s == ',') s++;
2369 }
2370 s++;
2371 }
2372 while (isspace(*s)) s++;
2373 if (logbits == 0) logbits = LOG_MAIN;
2374 log_write(0, logbits, "%s", string_printing(s));
2375 }
2376 break;
2377
2378 #ifdef WITH_CONTENT_SCAN
2379 case ACLC_MALWARE:
2380 {
2381 /* Seperate the regular expression and any optional parameters. */
2382 uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size);
2383 /* Run the malware backend. */
2384 rc = malware(&ss);
2385 /* Modify return code based upon the existance of options. */
2386 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2387 != NULL) {
2388 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
2389 {
2390 /* FAIL so that the message is passed to the next ACL */
2391 rc = FAIL;
2392 }
2393 }
2394 }
2395 break;
2396
2397 case ACLC_MIME_REGEX:
2398 rc = mime_regex(&arg);
2399 break;
2400 #endif
2401
2402 case ACLC_RECIPIENTS:
2403 rc = match_address_list(addr->address, TRUE, TRUE, &arg, NULL, -1, 0,
2404 &recipient_data);
2405 break;
2406
2407 #ifdef WITH_CONTENT_SCAN
2408 case ACLC_REGEX:
2409 rc = regex(&arg);
2410 break;
2411 #endif
2412
2413 case ACLC_SENDER_DOMAINS:
2414 {
2415 uschar *sdomain;
2416 sdomain = Ustrrchr(sender_address, '@');
2417 sdomain = (sdomain == NULL)? US"" : sdomain + 1;
2418 rc = match_isinlist(sdomain, &arg, 0, &domainlist_anchor,
2419 sender_domain_cache, MCL_DOMAIN, TRUE, NULL);
2420 }
2421 break;
2422
2423 case ACLC_SENDERS:
2424 rc = match_address_list(sender_address, TRUE, TRUE, &arg,
2425 sender_address_cache, -1, 0, &sender_data);
2426 break;
2427
2428 /* Connection variables must persist forever */
2429
2430 case ACLC_SET:
2431 {
2432 int old_pool = store_pool;
2433 if (cb->u.varnumber < ACL_C_MAX) store_pool = POOL_PERM;
2434 acl_var[cb->u.varnumber] = string_copy(arg);
2435 store_pool = old_pool;
2436 }
2437 break;
2438
2439 #ifdef WITH_CONTENT_SCAN
2440 case ACLC_SPAM:
2441 {
2442 /* Seperate the regular expression and any optional parameters. */
2443 uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size);
2444 /* Run the spam backend. */
2445 rc = spam(&ss);
2446 /* Modify return code based upon the existance of options. */
2447 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2448 != NULL) {
2449 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
2450 {
2451 /* FAIL so that the message is passed to the next ACL */
2452 rc = FAIL;
2453 }
2454 }
2455 }
2456 break;
2457 #endif
2458
2459 #ifdef EXPERIMENTAL_SPF
2460 case ACLC_SPF:
2461 rc = spf_process(&arg, sender_address);
2462 break;
2463 #endif
2464
2465 /* If the verb is WARN, discard any user message from verification, because
2466 such messages are SMTP responses, not header additions. The latter come
2467 only from explicit "message" modifiers. However, put the user message into
2468 $acl_verify_message so it can be used in subsequent conditions or modifiers
2469 (until something changes it). */
2470
2471 case ACLC_VERIFY:
2472 rc = acl_verify(where, addr, arg, user_msgptr, log_msgptr, basic_errno);
2473 acl_verify_message = *user_msgptr;
2474 if (verb == ACL_WARN) *user_msgptr = NULL;
2475 break;
2476
2477 default:
2478 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown "
2479 "condition %d", cb->type);
2480 break;
2481 }
2482
2483 /* If a condition was negated, invert OK/FAIL. */
2484
2485 if (!cond_modifiers[cb->type] && cb->u.negated)
2486 {
2487 if (rc == OK) rc = FAIL;
2488 else if (rc == FAIL || rc == FAIL_DROP) rc = OK;
2489 }
2490
2491 if (rc != OK) break; /* Conditions loop */
2492 }
2493
2494
2495 /* If the result is the one for which "message" and/or "log_message" are used,
2496 handle the values of these options. Most verbs have but a single return for
2497 which the messages are relevant, but for "discard", it's useful to have the log
2498 message both when it succeeds and when it fails. Also, for an "accept" that
2499 appears in a QUIT ACL, we want to handle the user message. Since only "accept"
2500 and "warn" are permitted in that ACL, we don't need to test the verb.
2501
2502 These modifiers act in different ways:
2503
2504 "message" is a user message that will be included in an SMTP response. Unless
2505 it is empty, it overrides any previously set user message.
2506
2507 "log_message" is a non-user message, and it adds to any existing non-user
2508 message that is already set.
2509
2510 If there isn't a log message set, we make it the same as the user message. */
2511
2512 if (((rc == FAIL_DROP)? FAIL : rc) == msgcond[verb] ||
2513 (verb == ACL_DISCARD && rc == OK) ||
2514 (where == ACL_WHERE_QUIT))
2515 {
2516 uschar *expmessage;
2517
2518 /* If the verb is "warn", messages generated by conditions (verification or
2519 nested ACLs) are discarded. Only messages specified at this level are used.
2520 However, the value of an existing message is available in $acl_verify_message
2521 during expansions. */
2522
2523 uschar *old_user_msgptr = *user_msgptr;
2524 uschar *old_log_msgptr = (*log_msgptr != NULL)? *log_msgptr : old_user_msgptr;
2525
2526 if (verb == ACL_WARN) *log_msgptr = *user_msgptr = NULL;
2527
2528 if (user_message != NULL)
2529 {
2530 acl_verify_message = old_user_msgptr;
2531 expmessage = expand_string(user_message);
2532 if (expmessage == NULL)
2533 {
2534 if (!expand_string_forcedfail)
2535 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
2536 user_message, expand_string_message);
2537 }
2538 else if (expmessage[0] != 0) *user_msgptr = expmessage;
2539 }
2540
2541 if (log_message != NULL)
2542 {
2543 acl_verify_message = old_log_msgptr;
2544 expmessage = expand_string(log_message);
2545 if (expmessage == NULL)
2546 {
2547 if (!expand_string_forcedfail)
2548 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
2549 log_message, expand_string_message);
2550 }
2551 else if (expmessage[0] != 0)
2552 {
2553 *log_msgptr = (*log_msgptr == NULL)? expmessage :
2554 string_sprintf("%s: %s", expmessage, *log_msgptr);
2555 }
2556 }
2557
2558 /* If no log message, default it to the user message */
2559
2560 if (*log_msgptr == NULL) *log_msgptr = *user_msgptr;
2561 }
2562
2563 acl_verify_message = NULL;
2564 return rc;
2565 }
2566
2567
2568
2569
2570
2571 /*************************************************
2572 * Get line from a literal ACL *
2573 *************************************************/
2574
2575 /* This function is passed to acl_read() in order to extract individual lines
2576 of a literal ACL, which we access via static pointers. We can destroy the
2577 contents because this is called only once (the compiled ACL is remembered).
2578
2579 This code is intended to treat the data in the same way as lines in the main
2580 Exim configuration file. That is:
2581
2582 . Leading spaces are ignored.
2583
2584 . A \ at the end of a line is a continuation - trailing spaces after the \
2585 are permitted (this is because I don't believe in making invisible things
2586 significant). Leading spaces on the continued part of a line are ignored.
2587
2588 . Physical lines starting (significantly) with # are totally ignored, and
2589 may appear within a sequence of backslash-continued lines.
2590
2591 . Blank lines are ignored, but will end a sequence of continuations.
2592
2593 Arguments: none
2594 Returns: a pointer to the next line
2595 */
2596
2597
2598 static uschar *acl_text; /* Current pointer in the text */
2599 static uschar *acl_text_end; /* Points one past the terminating '0' */
2600
2601
2602 static uschar *
2603 acl_getline(void)
2604 {
2605 uschar *yield;
2606
2607 /* This loop handles leading blank lines and comments. */
2608
2609 for(;;)
2610 {
2611 while (isspace(*acl_text)) acl_text++; /* Leading spaces/empty lines */
2612 if (*acl_text == 0) return NULL; /* No more data */
2613 yield = acl_text; /* Potential data line */
2614
2615 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
2616
2617 /* If we hit the end before a newline, we have the whole logical line. If
2618 it's a comment, there's no more data to be given. Otherwise, yield it. */
2619
2620 if (*acl_text == 0) return (*yield == '#')? NULL : yield;
2621
2622 /* After reaching a newline, end this loop if the physical line does not
2623 start with '#'. If it does, it's a comment, and the loop continues. */
2624
2625 if (*yield != '#') break;
2626 }
2627
2628 /* This loop handles continuations. We know we have some real data, ending in
2629 newline. See if there is a continuation marker at the end (ignoring trailing
2630 white space). We know that *yield is not white space, so no need to test for
2631 cont > yield in the backwards scanning loop. */
2632
2633 for(;;)
2634 {
2635 uschar *cont;
2636 for (cont = acl_text - 1; isspace(*cont); cont--);
2637
2638 /* If no continuation follows, we are done. Mark the end of the line and
2639 return it. */
2640
2641 if (*cont != '\\')
2642 {
2643 *acl_text++ = 0;
2644 return yield;
2645 }
2646
2647 /* We have encountered a continuation. Skip over whitespace at the start of
2648 the next line, and indeed the whole of the next line or lines if they are
2649 comment lines. */
2650
2651 for (;;)
2652 {
2653 while (*(++acl_text) == ' ' || *acl_text == '\t');
2654 if (*acl_text != '#') break;
2655 while (*(++acl_text) != 0 && *acl_text != '\n');
2656 }
2657
2658 /* We have the start of a continuation line. Move all the rest of the data
2659 to join onto the previous line, and then find its end. If the end is not a
2660 newline, we are done. Otherwise loop to look for another continuation. */
2661
2662 memmove(cont, acl_text, acl_text_end - acl_text);
2663 acl_text_end -= acl_text - cont;
2664 acl_text = cont;
2665 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
2666 if (*acl_text == 0) return yield;
2667 }
2668
2669 /* Control does not reach here */
2670 }
2671
2672
2673
2674
2675
2676 /*************************************************
2677 * Check access using an ACL *
2678 *************************************************/
2679
2680 /* This function is called from address_check. It may recurse via
2681 acl_check_condition() - hence the use of a level to stop looping. The ACL is
2682 passed as a string which is expanded. A forced failure implies no access check
2683 is required. If the result is a single word, it is taken as the name of an ACL
2684 which is sought in the global ACL tree. Otherwise, it is taken as literal ACL
2685 text, complete with newlines, and parsed as such. In both cases, the ACL check
2686 is then run. This function uses an auxiliary function for acl_read() to call
2687 for reading individual lines of a literal ACL. This is acl_getline(), which
2688 appears immediately above.
2689
2690 Arguments:
2691 where where called from
2692 addr address item when called from RCPT; otherwise NULL
2693 s the input string; NULL is the same as an empty ACL => DENY
2694 level the nesting level
2695 user_msgptr where to put a user error (for SMTP response)
2696 log_msgptr where to put a logging message (not for SMTP response)
2697
2698 Returns: OK access is granted
2699 DISCARD access is apparently granted...
2700 FAIL access is denied
2701 FAIL_DROP access is denied; drop the connection
2702 DEFER can't tell at the moment
2703 ERROR disaster
2704 */
2705
2706 static int
2707 acl_check_internal(int where, address_item *addr, uschar *s, int level,
2708 uschar **user_msgptr, uschar **log_msgptr)
2709 {
2710 int fd = -1;
2711 acl_block *acl = NULL;
2712 uschar *acl_name = US"inline ACL";
2713 uschar *ss;
2714
2715 /* Catch configuration loops */
2716
2717 if (level > 20)
2718 {
2719 *log_msgptr = US"ACL nested too deep: possible loop";
2720 return ERROR;
2721 }
2722
2723 if (s == NULL)
2724 {
2725 HDEBUG(D_acl) debug_printf("ACL is NULL: implicit DENY\n");
2726 return FAIL;
2727 }
2728
2729 /* At top level, we expand the incoming string. At lower levels, it has already
2730 been expanded as part of condition processing. */
2731
2732 if (level == 0)
2733 {
2734 ss = expand_string(s);
2735 if (ss == NULL)
2736 {
2737 if (expand_string_forcedfail) return OK;
2738 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s", s,
2739 expand_string_message);
2740 return ERROR;
2741 }
2742 }
2743 else ss = s;
2744
2745 while (isspace(*ss))ss++;
2746
2747 /* If we can't find a named ACL, the default is to parse it as an inline one.
2748 (Unless it begins with a slash; non-existent files give rise to an error.) */
2749
2750 acl_text = ss;
2751
2752 /* Handle the case of a string that does not contain any spaces. Look for a
2753 named ACL among those read from the configuration, or a previously read file.
2754 It is possible that the pointer to the ACL is NULL if the configuration
2755 contains a name with no data. If not found, and the text begins with '/',
2756 read an ACL from a file, and save it so it can be re-used. */
2757
2758 if (Ustrchr(ss, ' ') == NULL)
2759 {
2760 tree_node *t = tree_search(acl_anchor, ss);
2761 if (t != NULL)
2762 {
2763 acl = (acl_block *)(t->data.ptr);
2764 if (acl == NULL)
2765 {
2766 HDEBUG(D_acl) debug_printf("ACL \"%s\" is empty: implicit DENY\n", ss);
2767 return FAIL;
2768 }
2769 acl_name = string_sprintf("ACL \"%s\"", ss);
2770 HDEBUG(D_acl) debug_printf("using ACL \"%s\"\n", ss);
2771 }
2772
2773 else if (*ss == '/')
2774 {
2775 struct stat statbuf;
2776 fd = Uopen(ss, O_RDONLY, 0);
2777 if (fd < 0)
2778 {
2779 *log_msgptr = string_sprintf("failed to open ACL file \"%s\": %s", ss,
2780 strerror(errno));
2781 return ERROR;
2782 }
2783
2784 if (fstat(fd, &statbuf) != 0)
2785 {
2786 *log_msgptr = string_sprintf("failed to fstat ACL file \"%s\": %s", ss,
2787 strerror(errno));
2788 return ERROR;
2789 }
2790
2791 acl_text = store_get(statbuf.st_size + 1);
2792 acl_text_end = acl_text + statbuf.st_size + 1;
2793
2794 if (read(fd, acl_text, statbuf.st_size) != statbuf.st_size)
2795 {
2796 *log_msgptr = string_sprintf("failed to read ACL file \"%s\": %s",
2797 ss, strerror(errno));
2798 return ERROR;
2799 }
2800 acl_text[statbuf.st_size] = 0;
2801 close(fd);
2802
2803 acl_name = string_sprintf("ACL \"%s\"", ss);
2804 HDEBUG(D_acl) debug_printf("read ACL from file %s\n", ss);
2805 }
2806 }
2807
2808 /* Parse an ACL that is still in text form. If it came from a file, remember it
2809 in the ACL tree, having read it into the POOL_PERM store pool so that it
2810 persists between multiple messages. */
2811
2812 if (acl == NULL)
2813 {
2814 int old_pool = store_pool;
2815 if (fd >= 0) store_pool = POOL_PERM;
2816 acl = acl_read(acl_getline, log_msgptr);
2817 store_pool = old_pool;
2818 if (acl == NULL && *log_msgptr != NULL) return ERROR;
2819 if (fd >= 0)
2820 {
2821 tree_node *t = store_get_perm(sizeof(tree_node) + Ustrlen(ss));
2822 Ustrcpy(t->name, ss);
2823 t->data.ptr = acl;
2824 (void)tree_insertnode(&acl_anchor, t);
2825 }
2826 }
2827
2828 /* Now we have an ACL to use. It's possible it may be NULL. */
2829
2830 while (acl != NULL)
2831 {
2832 int cond;
2833 int basic_errno = 0;
2834 BOOL endpass_seen = FALSE;
2835
2836 *log_msgptr = *user_msgptr = NULL;
2837 acl_temp_details = FALSE;
2838
2839 if (where == ACL_WHERE_QUIT &&
2840 acl->verb != ACL_ACCEPT &&
2841 acl->verb != ACL_WARN)
2842 {
2843 *log_msgptr = string_sprintf("\"%s\" is not allowed in a QUIT ACL",
2844 verbs[acl->verb]);
2845 return ERROR;
2846 }
2847
2848 HDEBUG(D_acl) debug_printf("processing \"%s\"\n", verbs[acl->verb]);
2849
2850 /* Clear out any search error message from a previous check before testing
2851 this condition. */
2852
2853 search_error_message = NULL;
2854 cond = acl_check_condition(acl->verb, acl->condition, where, addr, level,
2855 &endpass_seen, user_msgptr, log_msgptr, &basic_errno);
2856
2857 /* Handle special returns: DEFER causes a return except on a WARN verb;
2858 ERROR always causes a return. */
2859
2860 switch (cond)
2861 {
2862 case DEFER:
2863 HDEBUG(D_acl) debug_printf("%s: condition test deferred\n", verbs[acl->verb]);
2864 if (basic_errno != ERRNO_CALLOUTDEFER)
2865 {
2866 if (search_error_message != NULL && *search_error_message != 0)
2867 *log_msgptr = search_error_message;
2868 if (smtp_return_error_details) acl_temp_details = TRUE;
2869 }
2870 else
2871 {
2872 acl_temp_details = TRUE;
2873 }
2874 if (acl->verb != ACL_WARN) return DEFER;
2875 break;
2876
2877 default: /* Paranoia */
2878 case ERROR:
2879 HDEBUG(D_acl) debug_printf("%s: condition test error\n", verbs[acl->verb]);
2880 return ERROR;
2881
2882 case OK:
2883 HDEBUG(D_acl) debug_printf("%s: condition test succeeded\n",
2884 verbs[acl->verb]);
2885 break;
2886
2887 case FAIL:
2888 HDEBUG(D_acl) debug_printf("%s: condition test failed\n", verbs[acl->verb]);
2889 break;
2890
2891 /* DISCARD and DROP can happen only from a nested ACL condition, and
2892 DISCARD can happen only for an "accept" or "discard" verb. */
2893
2894 case DISCARD:
2895 HDEBUG(D_acl) debug_printf("%s: condition test yielded \"discard\"\n",
2896 verbs[acl->verb]);
2897 break;
2898
2899 case FAIL_DROP:
2900 HDEBUG(D_acl) debug_printf("%s: condition test yielded \"drop\"\n",
2901 verbs[acl->verb]);
2902 break;
2903 }
2904
2905 /* At this point, cond for most verbs is either OK or FAIL or (as a result of
2906 a nested ACL condition) FAIL_DROP. However, for WARN, cond may be DEFER, and
2907 for ACCEPT and DISCARD, it may be DISCARD after a nested ACL call. */
2908
2909 switch(acl->verb)
2910 {
2911 case ACL_ACCEPT:
2912 if (cond == OK || cond == DISCARD) return cond;
2913 if (endpass_seen)
2914 {
2915 HDEBUG(D_acl) debug_printf("accept: endpass encountered - denying access\n");
2916 return cond;
2917 }
2918 break;
2919
2920 case ACL_DEFER:
2921 if (cond == OK)
2922 {
2923 acl_temp_details = TRUE;
2924 return DEFER;
2925 }
2926 break;
2927
2928 case ACL_DENY:
2929 if (cond == OK) return FAIL;
2930 break;
2931
2932 case ACL_DISCARD:
2933 if (cond == OK || cond == DISCARD) return DISCARD;
2934 if (endpass_seen)
2935 {
2936 HDEBUG(D_acl) debug_printf("discard: endpass encountered - denying access\n");
2937 return cond;
2938 }
2939 break;
2940
2941 case ACL_DROP:
2942 if (cond == OK) return FAIL_DROP;
2943 break;
2944
2945 case ACL_REQUIRE:
2946 if (cond != OK) return cond;
2947 break;
2948
2949 case ACL_WARN:
2950 if (cond == OK)
2951 acl_warn(where, *user_msgptr, *log_msgptr);
2952 else if (cond == DEFER)
2953 log_write(0, LOG_MAIN, "%s Warning: ACL \"warn\" statement skipped: "
2954 "condition test deferred%s%s", host_and_ident(TRUE),
2955 (*log_msgptr == NULL)? US"" : US": ",
2956 (*log_msgptr == NULL)? US"" : *log_msgptr);
2957 *log_msgptr = *user_msgptr = NULL; /* In case implicit DENY follows */
2958 break;
2959
2960 default:
2961 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown verb %d",
2962 acl->verb);
2963 break;
2964 }
2965
2966 /* Pass to the next ACL item */
2967
2968 acl = acl->next;
2969 }
2970
2971 /* We have reached the end of the ACL. This is an implicit DENY. */
2972
2973 HDEBUG(D_acl) debug_printf("end of %s: implicit DENY\n", acl_name);
2974 return FAIL;
2975 }
2976
2977
2978 /*************************************************
2979 * Check access using an ACL *
2980 *************************************************/
2981
2982 /* This is the external interface for ACL checks. It sets up an address and the
2983 expansions for $domain and $local_part when called after RCPT, then calls
2984 acl_check_internal() to do the actual work.
2985
2986 Arguments:
2987 where ACL_WHERE_xxxx indicating where called from
2988 data_string RCPT address, or SMTP command argument, or NULL
2989 s the input string; NULL is the same as an empty ACL => DENY
2990 user_msgptr where to put a user error (for SMTP response)
2991 log_msgptr where to put a logging message (not for SMTP response)
2992
2993 Returns: OK access is granted by an ACCEPT verb
2994 DISCARD access is granted by a DISCARD verb
2995 FAIL access is denied
2996 FAIL_DROP access is denied; drop the connection
2997 DEFER can't tell at the moment
2998 ERROR disaster
2999 */
3000
3001 int
3002 acl_check(int where, uschar *data_string, uschar *s, uschar **user_msgptr,
3003 uschar **log_msgptr)
3004 {
3005 int rc;
3006 address_item adb;
3007 address_item *addr;
3008
3009 *user_msgptr = *log_msgptr = NULL;
3010 sender_verified_failed = NULL;
3011
3012 if (where == ACL_WHERE_RCPT)
3013 {
3014 adb = address_defaults;
3015 addr = &adb;
3016 addr->address = data_string;
3017 if (deliver_split_address(addr) == DEFER)
3018 {
3019 *log_msgptr = US"defer in percent_hack_domains check";
3020 return DEFER;
3021 }
3022 deliver_domain = addr->domain;
3023 deliver_localpart = addr->local_part;
3024 }
3025 else
3026 {
3027 addr = NULL;
3028 smtp_command_argument = data_string;
3029 }
3030
3031 rc = acl_check_internal(where, addr, s, 0, user_msgptr, log_msgptr);
3032
3033 smtp_command_argument = deliver_domain =
3034 deliver_localpart = deliver_address_data = sender_address_data = NULL;
3035
3036 /* A DISCARD response is permitted only for message ACLs, excluding the PREDATA
3037 ACL, which is really in the middle of an SMTP command. */
3038
3039 if (rc == DISCARD)
3040 {
3041 if (where > ACL_WHERE_NOTSMTP || where == ACL_WHERE_PREDATA)
3042 {
3043 log_write(0, LOG_MAIN|LOG_PANIC, "\"discard\" verb not allowed in %s "
3044 "ACL", acl_wherenames[where]);
3045 return ERROR;
3046 }
3047 return DISCARD;
3048 }
3049
3050 /* A DROP response is not permitted from MAILAUTH */
3051
3052 if (rc == FAIL_DROP && where == ACL_WHERE_MAILAUTH)
3053 {
3054 log_write(0, LOG_MAIN|LOG_PANIC, "\"drop\" verb not allowed in %s "
3055 "ACL", acl_wherenames[where]);
3056 return ERROR;
3057 }
3058
3059 /* Before giving an error response, take a look at the length of any user
3060 message, and split it up into multiple lines if possible. */
3061
3062 if (rc != OK && *user_msgptr != NULL && Ustrlen(*user_msgptr) > 75)
3063 {
3064 uschar *s = *user_msgptr = string_copy(*user_msgptr);
3065 uschar *ss = s;
3066
3067 for (;;)
3068 {
3069 int i = 0;
3070 while (i < 75 && *ss != 0 && *ss != '\n') ss++, i++;
3071 if (*ss == 0) break;
3072 if (*ss == '\n')
3073 s = ++ss;
3074 else
3075 {
3076 uschar *t = ss + 1;
3077 uschar *tt = NULL;
3078 while (--t > s + 35)
3079 {
3080 if (*t == ' ')
3081 {
3082 if (t[-1] == ':') { tt = t; break; }
3083 if (tt == NULL) tt = t;
3084 }
3085 }
3086
3087 if (tt == NULL) /* Can't split behind - try ahead */
3088 {
3089 t = ss + 1;
3090 while (*t != 0)
3091 {
3092 if (*t == ' ' || *t == '\n')
3093 { tt = t; break; }
3094 t++;
3095 }
3096 }
3097
3098 if (tt == NULL) break; /* Can't find anywhere to split */
3099 *tt = '\n';
3100 s = ss = tt+1;
3101 }
3102 }
3103 }
3104
3105 return rc;
3106 }
3107
3108 /* End of acl.c */