Update to 4.63.
[exim.git] / src / src / acl.c
1 /* $Cambridge: exim/src/src/acl.c,v 1.59 2006/06/07 15:06:26 fanf2 Exp $ */
2
3 /*************************************************
4 * Exim - an Internet mail transport agent *
5 *************************************************/
6
7 /* Copyright (c) University of Cambridge 1995 - 2006 */
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, and the cond_expand_at_top and uschar cond_modifiers tables lower
36 down. */
37
38 enum { ACLC_ACL,
39 ACLC_ADD_HEADER,
40 ACLC_AUTHENTICATED,
41 #ifdef EXPERIMENTAL_BRIGHTMAIL
42 ACLC_BMI_OPTIN,
43 #endif
44 ACLC_CONDITION,
45 ACLC_CONTROL,
46 #ifdef WITH_CONTENT_SCAN
47 ACLC_DECODE,
48 #endif
49 ACLC_DELAY,
50 #ifdef WITH_OLD_DEMIME
51 ACLC_DEMIME,
52 #endif
53 #ifdef EXPERIMENTAL_DOMAINKEYS
54 ACLC_DK_DOMAIN_SOURCE,
55 ACLC_DK_POLICY,
56 ACLC_DK_SENDER_DOMAINS,
57 ACLC_DK_SENDER_LOCAL_PARTS,
58 ACLC_DK_SENDERS,
59 ACLC_DK_STATUS,
60 #endif
61 ACLC_DNSLISTS,
62 ACLC_DOMAINS,
63 ACLC_ENCRYPTED,
64 ACLC_ENDPASS,
65 ACLC_HOSTS,
66 ACLC_LOCAL_PARTS,
67 ACLC_LOG_MESSAGE,
68 ACLC_LOGWRITE,
69 #ifdef WITH_CONTENT_SCAN
70 ACLC_MALWARE,
71 #endif
72 ACLC_MESSAGE,
73 #ifdef WITH_CONTENT_SCAN
74 ACLC_MIME_REGEX,
75 #endif
76 ACLC_RATELIMIT,
77 ACLC_RECIPIENTS,
78 #ifdef WITH_CONTENT_SCAN
79 ACLC_REGEX,
80 #endif
81 ACLC_SENDER_DOMAINS,
82 ACLC_SENDERS,
83 ACLC_SET,
84 #ifdef WITH_CONTENT_SCAN
85 ACLC_SPAM,
86 #endif
87 #ifdef EXPERIMENTAL_SPF
88 ACLC_SPF,
89 #endif
90 ACLC_VERIFY };
91
92 /* ACL conditions/modifiers: "delay", "control", "endpass", "message",
93 "log_message", "logwrite", and "set" are modifiers that look like conditions
94 but always return TRUE. They are used for their side effects. */
95
96 static uschar *conditions[] = {
97 US"acl",
98 US"add_header",
99 US"authenticated",
100 #ifdef EXPERIMENTAL_BRIGHTMAIL
101 US"bmi_optin",
102 #endif
103 US"condition",
104 US"control",
105 #ifdef WITH_CONTENT_SCAN
106 US"decode",
107 #endif
108 US"delay",
109 #ifdef WITH_OLD_DEMIME
110 US"demime",
111 #endif
112 #ifdef EXPERIMENTAL_DOMAINKEYS
113 US"dk_domain_source",
114 US"dk_policy",
115 US"dk_sender_domains",
116 US"dk_sender_local_parts",
117 US"dk_senders",
118 US"dk_status",
119 #endif
120 US"dnslists", US"domains", US"encrypted",
121 US"endpass", US"hosts", US"local_parts", US"log_message", US"logwrite",
122 #ifdef WITH_CONTENT_SCAN
123 US"malware",
124 #endif
125 US"message",
126 #ifdef WITH_CONTENT_SCAN
127 US"mime_regex",
128 #endif
129 US"ratelimit",
130 US"recipients",
131 #ifdef WITH_CONTENT_SCAN
132 US"regex",
133 #endif
134 US"sender_domains", US"senders", US"set",
135 #ifdef WITH_CONTENT_SCAN
136 US"spam",
137 #endif
138 #ifdef EXPERIMENTAL_SPF
139 US"spf",
140 #endif
141 US"verify" };
142
143
144 /* Return values from decode_control(); keep in step with the table of names
145 that follows! */
146
147 enum {
148 CONTROL_AUTH_UNADVERTISED,
149 #ifdef EXPERIMENTAL_BRIGHTMAIL
150 CONTROL_BMI_RUN,
151 #endif
152 #ifdef EXPERIMENTAL_DOMAINKEYS
153 CONTROL_DK_VERIFY,
154 #endif
155 CONTROL_ERROR,
156 CONTROL_CASEFUL_LOCAL_PART,
157 CONTROL_CASELOWER_LOCAL_PART,
158 CONTROL_ENFORCE_SYNC,
159 CONTROL_NO_ENFORCE_SYNC,
160 CONTROL_FREEZE,
161 CONTROL_QUEUE_ONLY,
162 CONTROL_SUBMISSION,
163 CONTROL_SUPPRESS_LOCAL_FIXUPS,
164 #ifdef WITH_CONTENT_SCAN
165 CONTROL_NO_MBOX_UNSPOOL,
166 #endif
167 CONTROL_FAKEDEFER,
168 CONTROL_FAKEREJECT,
169 CONTROL_NO_MULTILINE
170 };
171
172 /* ACL control names; keep in step with the table above! This list is used for
173 turning ids into names. The actual list of recognized names is in the variable
174 control_def controls_list[] below. The fact that there are two lists is a mess
175 and should be tidied up. */
176
177 static uschar *controls[] = {
178 US"allow_auth_unadvertised",
179 #ifdef EXPERIMENTAL_BRIGHTMAIL
180 US"bmi_run",
181 #endif
182 #ifdef EXPERIMENTAL_DOMAINKEYS
183 US"dk_verify",
184 #endif
185 US"error",
186 US"caseful_local_part",
187 US"caselower_local_part",
188 US"enforce_sync",
189 US"no_enforce_sync",
190 US"freeze",
191 US"queue_only",
192 US"submission",
193 US"suppress_local_fixups",
194 #ifdef WITH_CONTENT_SCAN
195 US"no_mbox_unspool",
196 #endif
197 US"no_multiline"
198 };
199
200 /* Flags to indicate for which conditions /modifiers a string expansion is done
201 at the outer level. In the other cases, expansion already occurs in the
202 checking functions. */
203
204 static uschar cond_expand_at_top[] = {
205 TRUE, /* acl */
206 TRUE, /* add_header */
207 FALSE, /* authenticated */
208 #ifdef EXPERIMENTAL_BRIGHTMAIL
209 TRUE, /* bmi_optin */
210 #endif
211 TRUE, /* condition */
212 TRUE, /* control */
213 #ifdef WITH_CONTENT_SCAN
214 TRUE, /* decode */
215 #endif
216 TRUE, /* delay */
217 #ifdef WITH_OLD_DEMIME
218 TRUE, /* demime */
219 #endif
220 #ifdef EXPERIMENTAL_DOMAINKEYS
221 TRUE, /* dk_domain_source */
222 TRUE, /* dk_policy */
223 TRUE, /* dk_sender_domains */
224 TRUE, /* dk_sender_local_parts */
225 TRUE, /* dk_senders */
226 TRUE, /* dk_status */
227 #endif
228 TRUE, /* dnslists */
229 FALSE, /* domains */
230 FALSE, /* encrypted */
231 TRUE, /* endpass */
232 FALSE, /* hosts */
233 FALSE, /* local_parts */
234 TRUE, /* log_message */
235 TRUE, /* logwrite */
236 #ifdef WITH_CONTENT_SCAN
237 TRUE, /* malware */
238 #endif
239 TRUE, /* message */
240 #ifdef WITH_CONTENT_SCAN
241 TRUE, /* mime_regex */
242 #endif
243 TRUE, /* ratelimit */
244 FALSE, /* recipients */
245 #ifdef WITH_CONTENT_SCAN
246 TRUE, /* regex */
247 #endif
248 FALSE, /* sender_domains */
249 FALSE, /* senders */
250 TRUE, /* set */
251 #ifdef WITH_CONTENT_SCAN
252 TRUE, /* spam */
253 #endif
254 #ifdef EXPERIMENTAL_SPF
255 TRUE, /* spf */
256 #endif
257 TRUE /* verify */
258 };
259
260 /* Flags to identify the modifiers */
261
262 static uschar cond_modifiers[] = {
263 FALSE, /* acl */
264 TRUE, /* add_header */
265 FALSE, /* authenticated */
266 #ifdef EXPERIMENTAL_BRIGHTMAIL
267 TRUE, /* bmi_optin */
268 #endif
269 FALSE, /* condition */
270 TRUE, /* control */
271 #ifdef WITH_CONTENT_SCAN
272 FALSE, /* decode */
273 #endif
274 TRUE, /* delay */
275 #ifdef WITH_OLD_DEMIME
276 FALSE, /* demime */
277 #endif
278 #ifdef EXPERIMENTAL_DOMAINKEYS
279 FALSE, /* dk_domain_source */
280 FALSE, /* dk_policy */
281 FALSE, /* dk_sender_domains */
282 FALSE, /* dk_sender_local_parts */
283 FALSE, /* dk_senders */
284 FALSE, /* dk_status */
285 #endif
286 FALSE, /* dnslists */
287 FALSE, /* domains */
288 FALSE, /* encrypted */
289 TRUE, /* endpass */
290 FALSE, /* hosts */
291 FALSE, /* local_parts */
292 TRUE, /* log_message */
293 TRUE, /* logwrite */
294 #ifdef WITH_CONTENT_SCAN
295 FALSE, /* malware */
296 #endif
297 TRUE, /* message */
298 #ifdef WITH_CONTENT_SCAN
299 FALSE, /* mime_regex */
300 #endif
301 FALSE, /* ratelimit */
302 FALSE, /* recipients */
303 #ifdef WITH_CONTENT_SCAN
304 FALSE, /* regex */
305 #endif
306 FALSE, /* sender_domains */
307 FALSE, /* senders */
308 TRUE, /* set */
309 #ifdef WITH_CONTENT_SCAN
310 FALSE, /* spam */
311 #endif
312 #ifdef EXPERIMENTAL_SPF
313 FALSE, /* spf */
314 #endif
315 FALSE /* verify */
316 };
317
318 /* Bit map vector of which conditions are not allowed at certain times. For
319 each condition, there's a bitmap of dis-allowed times. For some, it is easier
320 to specify the negation of a small number of allowed times. */
321
322 static unsigned int cond_forbids[] = {
323 0, /* acl */
324
325 (unsigned int)
326 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* add_header */
327 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
328 (1<<ACL_WHERE_MIME)|(1<<ACL_WHERE_NOTSMTP)),
329
330 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_CONNECT)| /* authenticated */
331 (1<<ACL_WHERE_HELO),
332
333 #ifdef EXPERIMENTAL_BRIGHTMAIL
334 (1<<ACL_WHERE_AUTH)| /* bmi_optin */
335 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
336 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_MIME)|
337 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
338 (1<<ACL_WHERE_MAILAUTH)|
339 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
340 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_PREDATA),
341 #endif
342
343 0, /* condition */
344
345 /* Certain types of control are always allowed, so we let it through
346 always and check in the control processing itself. */
347
348 0, /* control */
349
350 #ifdef WITH_CONTENT_SCAN
351 (unsigned int)
352 ~(1<<ACL_WHERE_MIME), /* decode */
353 #endif
354
355 0, /* delay */
356
357 #ifdef WITH_OLD_DEMIME
358 (unsigned int)
359 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)), /* demime */
360 #endif
361
362 #ifdef EXPERIMENTAL_DOMAINKEYS
363 (1<<ACL_WHERE_AUTH)| /* dk_domain_source */
364 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
365 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
366 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
367 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
368 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
369 (1<<ACL_WHERE_VRFY),
370
371 (1<<ACL_WHERE_AUTH)| /* dk_policy */
372 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
373 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
374 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
375 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
376 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
377 (1<<ACL_WHERE_VRFY),
378
379 (1<<ACL_WHERE_AUTH)| /* dk_sender_domains */
380 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
381 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
382 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
383 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
384 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
385 (1<<ACL_WHERE_VRFY),
386
387 (1<<ACL_WHERE_AUTH)| /* dk_sender_local_parts */
388 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
389 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
390 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
391 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
392 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
393 (1<<ACL_WHERE_VRFY),
394
395 (1<<ACL_WHERE_AUTH)| /* dk_senders */
396 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
397 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
398 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
399 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
400 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
401 (1<<ACL_WHERE_VRFY),
402
403 (1<<ACL_WHERE_AUTH)| /* dk_status */
404 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
405 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
406 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
407 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
408 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
409 (1<<ACL_WHERE_VRFY),
410 #endif
411
412 (1<<ACL_WHERE_NOTSMTP), /* dnslists */
413
414 (unsigned int)
415 ~(1<<ACL_WHERE_RCPT), /* domains */
416
417 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_CONNECT)| /* encrypted */
418 (1<<ACL_WHERE_HELO),
419
420 0, /* endpass */
421
422 (1<<ACL_WHERE_NOTSMTP), /* hosts */
423
424 (unsigned int)
425 ~(1<<ACL_WHERE_RCPT), /* local_parts */
426
427 0, /* log_message */
428
429 0, /* logwrite */
430
431 #ifdef WITH_CONTENT_SCAN
432 (unsigned int)
433 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)), /* malware */
434 #endif
435
436 0, /* message */
437
438 #ifdef WITH_CONTENT_SCAN
439 (unsigned int)
440 ~(1<<ACL_WHERE_MIME), /* mime_regex */
441 #endif
442
443 0, /* ratelimit */
444
445 (unsigned int)
446 ~(1<<ACL_WHERE_RCPT), /* recipients */
447
448 #ifdef WITH_CONTENT_SCAN
449 (unsigned int)
450 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* regex */
451 (1<<ACL_WHERE_MIME)),
452 #endif
453
454 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* sender_domains */
455 (1<<ACL_WHERE_HELO)|
456 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
457 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
458 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
459
460 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* senders */
461 (1<<ACL_WHERE_HELO)|
462 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
463 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
464 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
465
466 0, /* set */
467
468 #ifdef WITH_CONTENT_SCAN
469 (unsigned int)
470 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)), /* spam */
471 #endif
472
473 #ifdef EXPERIMENTAL_SPF
474 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* spf */
475 (1<<ACL_WHERE_HELO)|
476 (1<<ACL_WHERE_MAILAUTH)|
477 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
478 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
479 #endif
480
481 /* Certain types of verify are always allowed, so we let it through
482 always and check in the verify function itself */
483
484 0 /* verify */
485 };
486
487
488 /* Bit map vector of which controls are not allowed at certain times. For
489 each control, there's a bitmap of dis-allowed times. For some, it is easier to
490 specify the negation of a small number of allowed times. */
491
492 static unsigned int control_forbids[] = {
493 (unsigned int)
494 ~((1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)), /* allow_auth_unadvertised */
495
496 #ifdef EXPERIMENTAL_BRIGHTMAIL
497 0, /* bmi_run */
498 #endif
499
500 #ifdef EXPERIMENTAL_DOMAINKEYS
501 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), /* dk_verify */
502 #endif
503
504 0, /* error */
505
506 (unsigned int)
507 ~(1<<ACL_WHERE_RCPT), /* caseful_local_part */
508
509 (unsigned int)
510 ~(1<<ACL_WHERE_RCPT), /* caselower_local_part */
511
512 (1<<ACL_WHERE_NOTSMTP), /* enforce_sync */
513
514 (1<<ACL_WHERE_NOTSMTP), /* no_enforce_sync */
515
516 (unsigned int)
517 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* freeze */
518 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
519 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)),
520
521 (unsigned int)
522 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* queue_only */
523 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
524 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)),
525
526 (unsigned int)
527 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* submission */
528 (1<<ACL_WHERE_PREDATA)),
529
530 (unsigned int)
531 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* suppress_local_fixups */
532 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_PREDATA)),
533
534 #ifdef WITH_CONTENT_SCAN
535 (unsigned int)
536 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* no_mbox_unspool */
537 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
538 (1<<ACL_WHERE_MIME)),
539 #endif
540
541 (unsigned int)
542 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakedefer */
543 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
544 (1<<ACL_WHERE_MIME)),
545
546 (unsigned int)
547 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakereject */
548 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
549 (1<<ACL_WHERE_MIME)),
550
551 (1<<ACL_WHERE_NOTSMTP) /* no_multiline */
552 };
553
554 /* Structure listing various control arguments, with their characteristics. */
555
556 typedef struct control_def {
557 uschar *name;
558 int value; /* CONTROL_xxx value */
559 BOOL has_option; /* Has /option(s) following */
560 } control_def;
561
562 static control_def controls_list[] = {
563 { US"allow_auth_unadvertised", CONTROL_AUTH_UNADVERTISED, FALSE },
564 #ifdef EXPERIMENTAL_BRIGHTMAIL
565 { US"bmi_run", CONTROL_BMI_RUN, FALSE },
566 #endif
567 #ifdef EXPERIMENTAL_DOMAINKEYS
568 { US"dk_verify", CONTROL_DK_VERIFY, FALSE },
569 #endif
570 { US"caseful_local_part", CONTROL_CASEFUL_LOCAL_PART, FALSE },
571 { US"caselower_local_part", CONTROL_CASELOWER_LOCAL_PART, FALSE },
572 { US"enforce_sync", CONTROL_ENFORCE_SYNC, FALSE },
573 { US"freeze", CONTROL_FREEZE, TRUE },
574 { US"no_enforce_sync", CONTROL_NO_ENFORCE_SYNC, FALSE },
575 { US"no_multiline_responses", CONTROL_NO_MULTILINE, FALSE },
576 { US"queue_only", CONTROL_QUEUE_ONLY, FALSE },
577 #ifdef WITH_CONTENT_SCAN
578 { US"no_mbox_unspool", CONTROL_NO_MBOX_UNSPOOL, FALSE },
579 #endif
580 { US"fakedefer", CONTROL_FAKEDEFER, TRUE },
581 { US"fakereject", CONTROL_FAKEREJECT, TRUE },
582 { US"submission", CONTROL_SUBMISSION, TRUE },
583 { US"suppress_local_fixups", CONTROL_SUPPRESS_LOCAL_FIXUPS, FALSE }
584 };
585
586 /* Support data structures for Client SMTP Authorization. acl_verify_csa()
587 caches its result in a tree to avoid repeated DNS queries. The result is an
588 integer code which is used as an index into the following tables of
589 explanatory strings and verification return codes. */
590
591 static tree_node *csa_cache = NULL;
592
593 enum { CSA_UNKNOWN, CSA_OK, CSA_DEFER_SRV, CSA_DEFER_ADDR,
594 CSA_FAIL_EXPLICIT, CSA_FAIL_DOMAIN, CSA_FAIL_NOADDR, CSA_FAIL_MISMATCH };
595
596 /* The acl_verify_csa() return code is translated into an acl_verify() return
597 code using the following table. It is OK unless the client is definitely not
598 authorized. This is because CSA is supposed to be optional for sending sites,
599 so recipients should not be too strict about checking it - especially because
600 DNS problems are quite likely to occur. It's possible to use $csa_status in
601 further ACL conditions to distinguish ok, unknown, and defer if required, but
602 the aim is to make the usual configuration simple. */
603
604 static int csa_return_code[] = {
605 OK, OK, OK, OK,
606 FAIL, FAIL, FAIL, FAIL
607 };
608
609 static uschar *csa_status_string[] = {
610 US"unknown", US"ok", US"defer", US"defer",
611 US"fail", US"fail", US"fail", US"fail"
612 };
613
614 static uschar *csa_reason_string[] = {
615 US"unknown",
616 US"ok",
617 US"deferred (SRV lookup failed)",
618 US"deferred (target address lookup failed)",
619 US"failed (explicit authorization required)",
620 US"failed (host name not authorized)",
621 US"failed (no authorized addresses)",
622 US"failed (client address mismatch)"
623 };
624
625 /* Enable recursion between acl_check_internal() and acl_check_condition() */
626
627 static int acl_check_internal(int, address_item *, uschar *, int, uschar **,
628 uschar **);
629
630
631 /*************************************************
632 * Pick out name from list *
633 *************************************************/
634
635 /* Use a binary chop method
636
637 Arguments:
638 name name to find
639 list list of names
640 end size of list
641
642 Returns: offset in list, or -1 if not found
643 */
644
645 static int
646 acl_checkname(uschar *name, uschar **list, int end)
647 {
648 int start = 0;
649
650 while (start < end)
651 {
652 int mid = (start + end)/2;
653 int c = Ustrcmp(name, list[mid]);
654 if (c == 0) return mid;
655 if (c < 0) end = mid; else start = mid + 1;
656 }
657
658 return -1;
659 }
660
661
662 /*************************************************
663 * Read and parse one ACL *
664 *************************************************/
665
666 /* This function is called both from readconf in order to parse the ACLs in the
667 configuration file, and also when an ACL is encountered dynamically (e.g. as
668 the result of an expansion). It is given a function to call in order to
669 retrieve the lines of the ACL. This function handles skipping comments and
670 blank lines (where relevant).
671
672 Arguments:
673 func function to get next line of ACL
674 error where to put an error message
675
676 Returns: pointer to ACL, or NULL
677 NULL can be legal (empty ACL); in this case error will be NULL
678 */
679
680 acl_block *
681 acl_read(uschar *(*func)(void), uschar **error)
682 {
683 acl_block *yield = NULL;
684 acl_block **lastp = &yield;
685 acl_block *this = NULL;
686 acl_condition_block *cond;
687 acl_condition_block **condp = NULL;
688 uschar *s;
689
690 *error = NULL;
691
692 while ((s = (*func)()) != NULL)
693 {
694 int v, c;
695 BOOL negated = FALSE;
696 uschar *saveline = s;
697 uschar name[64];
698
699 /* Conditions (but not verbs) are allowed to be negated by an initial
700 exclamation mark. */
701
702 while (isspace(*s)) s++;
703 if (*s == '!')
704 {
705 negated = TRUE;
706 s++;
707 }
708
709 /* Read the name of a verb or a condition, or the start of a new ACL, which
710 can be started by a name, or by a macro definition. */
711
712 s = readconf_readname(name, sizeof(name), s);
713 if (*s == ':' || isupper(name[0] && *s == '=')) return yield;
714
715 /* If a verb is unrecognized, it may be another condition or modifier that
716 continues the previous verb. */
717
718 v = acl_checkname(name, verbs, sizeof(verbs)/sizeof(char *));
719 if (v < 0)
720 {
721 if (this == NULL)
722 {
723 *error = string_sprintf("unknown ACL verb in \"%s\"", saveline);
724 return NULL;
725 }
726 }
727
728 /* New verb */
729
730 else
731 {
732 if (negated)
733 {
734 *error = string_sprintf("malformed ACL line \"%s\"", saveline);
735 return NULL;
736 }
737 this = store_get(sizeof(acl_block));
738 *lastp = this;
739 lastp = &(this->next);
740 this->next = NULL;
741 this->verb = v;
742 this->condition = NULL;
743 condp = &(this->condition);
744 if (*s == 0) continue; /* No condition on this line */
745 if (*s == '!')
746 {
747 negated = TRUE;
748 s++;
749 }
750 s = readconf_readname(name, sizeof(name), s); /* Condition name */
751 }
752
753 /* Handle a condition or modifier. */
754
755 c = acl_checkname(name, conditions, sizeof(conditions)/sizeof(char *));
756 if (c < 0)
757 {
758 *error = string_sprintf("unknown ACL condition/modifier in \"%s\"",
759 saveline);
760 return NULL;
761 }
762
763 /* The modifiers may not be negated */
764
765 if (negated && cond_modifiers[c])
766 {
767 *error = string_sprintf("ACL error: negation is not allowed with "
768 "\"%s\"", conditions[c]);
769 return NULL;
770 }
771
772 /* ENDPASS may occur only with ACCEPT or DISCARD. */
773
774 if (c == ACLC_ENDPASS &&
775 this->verb != ACL_ACCEPT &&
776 this->verb != ACL_DISCARD)
777 {
778 *error = string_sprintf("ACL error: \"%s\" is not allowed with \"%s\"",
779 conditions[c], verbs[this->verb]);
780 return NULL;
781 }
782
783 cond = store_get(sizeof(acl_condition_block));
784 cond->next = NULL;
785 cond->type = c;
786 cond->u.negated = negated;
787
788 *condp = cond;
789 condp = &(cond->next);
790
791 /* The "set" modifier is different in that its argument is "name=value"
792 rather than just a value, and we can check the validity of the name, which
793 gives us a variable number to insert into the data block. */
794
795 if (c == ACLC_SET)
796 {
797 int offset, max, n;
798 uschar *endptr;
799
800 if (Ustrncmp(s, "acl_", 4) != 0) goto BAD_ACL_VAR;
801 if (s[4] == 'c')
802 {
803 offset = 0;
804 max = ACL_CVARS;
805 }
806 else if (s[4] == 'm')
807 {
808 offset = ACL_CVARS;
809 max = ACL_MVARS;
810 }
811 else goto BAD_ACL_VAR;
812
813 n = Ustrtoul(s + 5, &endptr, 10);
814 if ((*endptr != 0 && *endptr != '=' && !isspace(*endptr)) || n >= max)
815 {
816 BAD_ACL_VAR:
817 *error = string_sprintf("syntax error or unrecognized name after "
818 "\"set\" in ACL modifier \"set %s\"", s);
819 return NULL;
820 }
821
822 cond->u.varnumber = n + offset;
823 s = endptr;
824 while (isspace(*s)) s++;
825 }
826
827 /* For "set", we are now positioned for the data. For the others, only
828 "endpass" has no data */
829
830 if (c != ACLC_ENDPASS)
831 {
832 if (*s++ != '=')
833 {
834 *error = string_sprintf("\"=\" missing after ACL \"%s\" %s", name,
835 cond_modifiers[c]? US"modifier" : US"condition");
836 return NULL;
837 }
838 while (isspace(*s)) s++;
839 cond->arg = string_copy(s);
840 }
841 }
842
843 return yield;
844 }
845
846
847
848 /*************************************************
849 * Set up added header line(s) *
850 *************************************************/
851
852 /* This function is called by the add_header modifier, and also from acl_warn()
853 to implement the now-deprecated way of adding header lines using "message" on a
854 "warn" verb. The argument is treated as a sequence of header lines which are
855 added to a chain, provided there isn't an identical one already there.
856
857 Argument: string of header lines
858 Returns: nothing
859 */
860
861 static void
862 setup_header(uschar *hstring)
863 {
864 uschar *p, *q;
865 int hlen = Ustrlen(hstring);
866
867 /* An empty string does nothing; otherwise add a final newline if necessary. */
868
869 if (hlen <= 0) return;
870 if (hstring[hlen-1] != '\n') hstring = string_sprintf("%s\n", hstring);
871
872 /* Loop for multiple header lines, taking care about continuations */
873
874 for (p = q = hstring; *p != 0; )
875 {
876 uschar *s;
877 int newtype = htype_add_bot;
878 header_line **hptr = &acl_added_headers;
879
880 /* Find next header line within the string */
881
882 for (;;)
883 {
884 q = Ustrchr(q, '\n');
885 if (*(++q) != ' ' && *q != '\t') break;
886 }
887
888 /* If the line starts with a colon, interpret the instruction for where to
889 add it. This temporarily sets up a new type. */
890
891 if (*p == ':')
892 {
893 if (strncmpic(p, US":after_received:", 16) == 0)
894 {
895 newtype = htype_add_rec;
896 p += 16;
897 }
898 else if (strncmpic(p, US":at_start_rfc:", 14) == 0)
899 {
900 newtype = htype_add_rfc;
901 p += 14;
902 }
903 else if (strncmpic(p, US":at_start:", 10) == 0)
904 {
905 newtype = htype_add_top;
906 p += 10;
907 }
908 else if (strncmpic(p, US":at_end:", 8) == 0)
909 {
910 newtype = htype_add_bot;
911 p += 8;
912 }
913 while (*p == ' ' || *p == '\t') p++;
914 }
915
916 /* See if this line starts with a header name, and if not, add X-ACL-Warn:
917 to the front of it. */
918
919 for (s = p; s < q - 1; s++)
920 {
921 if (*s == ':' || !isgraph(*s)) break;
922 }
923
924 s = string_sprintf("%s%.*s", (*s == ':')? "" : "X-ACL-Warn: ", q - p, p);
925 hlen = Ustrlen(s);
926
927 /* See if this line has already been added */
928
929 while (*hptr != NULL)
930 {
931 if (Ustrncmp((*hptr)->text, s, hlen) == 0) break;
932 hptr = &((*hptr)->next);
933 }
934
935 /* Add if not previously present */
936
937 if (*hptr == NULL)
938 {
939 header_line *h = store_get(sizeof(header_line));
940 h->text = s;
941 h->next = NULL;
942 h->type = newtype;
943 h->slen = hlen;
944 *hptr = h;
945 hptr = &(h->next);
946 }
947
948 /* Advance for next header line within the string */
949
950 p = q;
951 }
952 }
953
954
955
956
957 /*************************************************
958 * Handle warnings *
959 *************************************************/
960
961 /* This function is called when a WARN verb's conditions are true. It adds to
962 the message's headers, and/or writes information to the log. In each case, this
963 only happens once (per message for headers, per connection for log).
964
965 ** NOTE: The header adding action using the "message" setting is historic, and
966 its use is now deprecated. The new add_header modifier should be used instead.
967
968 Arguments:
969 where ACL_WHERE_xxxx indicating which ACL this is
970 user_message message for adding to headers
971 log_message message for logging, if different
972
973 Returns: nothing
974 */
975
976 static void
977 acl_warn(int where, uschar *user_message, uschar *log_message)
978 {
979 if (log_message != NULL && log_message != user_message)
980 {
981 uschar *text;
982 string_item *logged;
983
984 text = string_sprintf("%s Warning: %s", host_and_ident(TRUE),
985 string_printing(log_message));
986
987 /* If a sender verification has failed, and the log message is "sender verify
988 failed", add the failure message. */
989
990 if (sender_verified_failed != NULL &&
991 sender_verified_failed->message != NULL &&
992 strcmpic(log_message, US"sender verify failed") == 0)
993 text = string_sprintf("%s: %s", text, sender_verified_failed->message);
994
995 /* Search previously logged warnings. They are kept in malloc
996 store so they can be freed at the start of a new message. */
997
998 for (logged = acl_warn_logged; logged != NULL; logged = logged->next)
999 if (Ustrcmp(logged->text, text) == 0) break;
1000
1001 if (logged == NULL)
1002 {
1003 int length = Ustrlen(text) + 1;
1004 log_write(0, LOG_MAIN, "%s", text);
1005 logged = store_malloc(sizeof(string_item) + length);
1006 logged->text = (uschar *)logged + sizeof(string_item);
1007 memcpy(logged->text, text, length);
1008 logged->next = acl_warn_logged;
1009 acl_warn_logged = logged;
1010 }
1011 }
1012
1013 /* If there's no user message, we are done. */
1014
1015 if (user_message == NULL) return;
1016
1017 /* If this isn't a message ACL, we can't do anything with a user message.
1018 Log an error. */
1019
1020 if (where > ACL_WHERE_NOTSMTP)
1021 {
1022 log_write(0, LOG_MAIN|LOG_PANIC, "ACL \"warn\" with \"message\" setting "
1023 "found in a non-message (%s) ACL: cannot specify header lines here: "
1024 "message ignored", acl_wherenames[where]);
1025 return;
1026 }
1027
1028 /* The code for setting up header lines is now abstracted into a separate
1029 function so that it can be used for the add_header modifier as well. */
1030
1031 setup_header(user_message);
1032 }
1033
1034
1035
1036 /*************************************************
1037 * Verify and check reverse DNS *
1038 *************************************************/
1039
1040 /* Called from acl_verify() below. We look up the host name(s) of the client IP
1041 address if this has not yet been done. The host_name_lookup() function checks
1042 that one of these names resolves to an address list that contains the client IP
1043 address, so we don't actually have to do the check here.
1044
1045 Arguments:
1046 user_msgptr pointer for user message
1047 log_msgptr pointer for log message
1048
1049 Returns: OK verification condition succeeded
1050 FAIL verification failed
1051 DEFER there was a problem verifying
1052 */
1053
1054 static int
1055 acl_verify_reverse(uschar **user_msgptr, uschar **log_msgptr)
1056 {
1057 int rc;
1058
1059 user_msgptr = user_msgptr; /* stop compiler warning */
1060
1061 /* Previous success */
1062
1063 if (sender_host_name != NULL) return OK;
1064
1065 /* Previous failure */
1066
1067 if (host_lookup_failed)
1068 {
1069 *log_msgptr = string_sprintf("host lookup failed%s", host_lookup_msg);
1070 return FAIL;
1071 }
1072
1073 /* Need to do a lookup */
1074
1075 HDEBUG(D_acl)
1076 debug_printf("looking up host name to force name/address consistency check\n");
1077
1078 if ((rc = host_name_lookup()) != OK)
1079 {
1080 *log_msgptr = (rc == DEFER)?
1081 US"host lookup deferred for reverse lookup check"
1082 :
1083 string_sprintf("host lookup failed for reverse lookup check%s",
1084 host_lookup_msg);
1085 return rc; /* DEFER or FAIL */
1086 }
1087
1088 host_build_sender_fullhost();
1089 return OK;
1090 }
1091
1092
1093
1094 /*************************************************
1095 * Check client IP address matches CSA target *
1096 *************************************************/
1097
1098 /* Called from acl_verify_csa() below. This routine scans a section of a DNS
1099 response for address records belonging to the CSA target hostname. The section
1100 is specified by the reset argument, either RESET_ADDITIONAL or RESET_ANSWERS.
1101 If one of the addresses matches the client's IP address, then the client is
1102 authorized by CSA. If there are target IP addresses but none of them match
1103 then the client is using an unauthorized IP address. If there are no target IP
1104 addresses then the client cannot be using an authorized IP address. (This is
1105 an odd configuration - why didn't the SRV record have a weight of 1 instead?)
1106
1107 Arguments:
1108 dnsa the DNS answer block
1109 dnss a DNS scan block for us to use
1110 reset option specifing what portion to scan, as described above
1111 target the target hostname to use for matching RR names
1112
1113 Returns: CSA_OK successfully authorized
1114 CSA_FAIL_MISMATCH addresses found but none matched
1115 CSA_FAIL_NOADDR no target addresses found
1116 */
1117
1118 static int
1119 acl_verify_csa_address(dns_answer *dnsa, dns_scan *dnss, int reset,
1120 uschar *target)
1121 {
1122 dns_record *rr;
1123 dns_address *da;
1124
1125 BOOL target_found = FALSE;
1126
1127 for (rr = dns_next_rr(dnsa, dnss, reset);
1128 rr != NULL;
1129 rr = dns_next_rr(dnsa, dnss, RESET_NEXT))
1130 {
1131 /* Check this is an address RR for the target hostname. */
1132
1133 if (rr->type != T_A
1134 #if HAVE_IPV6
1135 && rr->type != T_AAAA
1136 #ifdef SUPPORT_A6
1137 && rr->type != T_A6
1138 #endif
1139 #endif
1140 ) continue;
1141
1142 if (strcmpic(target, rr->name) != 0) continue;
1143
1144 target_found = TRUE;
1145
1146 /* Turn the target address RR into a list of textual IP addresses and scan
1147 the list. There may be more than one if it is an A6 RR. */
1148
1149 for (da = dns_address_from_rr(dnsa, rr); da != NULL; da = da->next)
1150 {
1151 /* If the client IP address matches the target IP address, it's good! */
1152
1153 DEBUG(D_acl) debug_printf("CSA target address is %s\n", da->address);
1154
1155 if (strcmpic(sender_host_address, da->address) == 0) return CSA_OK;
1156 }
1157 }
1158
1159 /* If we found some target addresses but none of them matched, the client is
1160 using an unauthorized IP address, otherwise the target has no authorized IP
1161 addresses. */
1162
1163 if (target_found) return CSA_FAIL_MISMATCH;
1164 else return CSA_FAIL_NOADDR;
1165 }
1166
1167
1168
1169 /*************************************************
1170 * Verify Client SMTP Authorization *
1171 *************************************************/
1172
1173 /* Called from acl_verify() below. This routine calls dns_lookup_special()
1174 to find the CSA SRV record corresponding to the domain argument, or
1175 $sender_helo_name if no argument is provided. It then checks that the
1176 client is authorized, and that its IP address corresponds to the SRV
1177 target's address by calling acl_verify_csa_address() above. The address
1178 should have been returned in the DNS response's ADDITIONAL section, but if
1179 not we perform another DNS lookup to get it.
1180
1181 Arguments:
1182 domain pointer to optional parameter following verify = csa
1183
1184 Returns: CSA_UNKNOWN no valid CSA record found
1185 CSA_OK successfully authorized
1186 CSA_FAIL_* client is definitely not authorized
1187 CSA_DEFER_* there was a DNS problem
1188 */
1189
1190 static int
1191 acl_verify_csa(uschar *domain)
1192 {
1193 tree_node *t;
1194 uschar *found, *p;
1195 int priority, weight, port;
1196 dns_answer dnsa;
1197 dns_scan dnss;
1198 dns_record *rr;
1199 int rc, type;
1200 uschar target[256];
1201
1202 /* Work out the domain we are using for the CSA lookup. The default is the
1203 client's HELO domain. If the client has not said HELO, use its IP address
1204 instead. If it's a local client (exim -bs), CSA isn't applicable. */
1205
1206 while (isspace(*domain) && *domain != '\0') ++domain;
1207 if (*domain == '\0') domain = sender_helo_name;
1208 if (domain == NULL) domain = sender_host_address;
1209 if (sender_host_address == NULL) return CSA_UNKNOWN;
1210
1211 /* If we have an address literal, strip off the framing ready for turning it
1212 into a domain. The framing consists of matched square brackets possibly
1213 containing a keyword and a colon before the actual IP address. */
1214
1215 if (domain[0] == '[')
1216 {
1217 uschar *start = Ustrchr(domain, ':');
1218 if (start == NULL) start = domain;
1219 domain = string_copyn(start + 1, Ustrlen(start) - 2);
1220 }
1221
1222 /* Turn domains that look like bare IP addresses into domains in the reverse
1223 DNS. This code also deals with address literals and $sender_host_address. It's
1224 not quite kosher to treat bare domains such as EHLO 192.0.2.57 the same as
1225 address literals, but it's probably the most friendly thing to do. This is an
1226 extension to CSA, so we allow it to be turned off for proper conformance. */
1227
1228 if (string_is_ip_address(domain, NULL) != 0)
1229 {
1230 if (!dns_csa_use_reverse) return CSA_UNKNOWN;
1231 dns_build_reverse(domain, target);
1232 domain = target;
1233 }
1234
1235 /* Find out if we've already done the CSA check for this domain. If we have,
1236 return the same result again. Otherwise build a new cached result structure
1237 for this domain. The name is filled in now, and the value is filled in when
1238 we return from this function. */
1239
1240 t = tree_search(csa_cache, domain);
1241 if (t != NULL) return t->data.val;
1242
1243 t = store_get_perm(sizeof(tree_node) + Ustrlen(domain));
1244 Ustrcpy(t->name, domain);
1245 (void)tree_insertnode(&csa_cache, t);
1246
1247 /* Now we are ready to do the actual DNS lookup(s). */
1248
1249 found = domain;
1250 switch (dns_special_lookup(&dnsa, domain, T_CSA, &found))
1251 {
1252 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1253
1254 default:
1255 return t->data.val = CSA_DEFER_SRV;
1256
1257 /* If we found nothing, the client's authorization is unknown. */
1258
1259 case DNS_NOMATCH:
1260 case DNS_NODATA:
1261 return t->data.val = CSA_UNKNOWN;
1262
1263 /* We got something! Go on to look at the reply in more detail. */
1264
1265 case DNS_SUCCEED:
1266 break;
1267 }
1268
1269 /* Scan the reply for well-formed CSA SRV records. */
1270
1271 for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS);
1272 rr != NULL;
1273 rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT))
1274 {
1275 if (rr->type != T_SRV) continue;
1276
1277 /* Extract the numerical SRV fields (p is incremented) */
1278
1279 p = rr->data;
1280 GETSHORT(priority, p);
1281 GETSHORT(weight, p);
1282 GETSHORT(port, p);
1283
1284 DEBUG(D_acl)
1285 debug_printf("CSA priority=%d weight=%d port=%d\n", priority, weight, port);
1286
1287 /* Check the CSA version number */
1288
1289 if (priority != 1) continue;
1290
1291 /* If the domain does not have a CSA SRV record of its own (i.e. the domain
1292 found by dns_special_lookup() is a parent of the one we asked for), we check
1293 the subdomain assertions in the port field. At the moment there's only one
1294 assertion: legitimate SMTP clients are all explicitly authorized with CSA
1295 SRV records of their own. */
1296
1297 if (found != domain)
1298 {
1299 if (port & 1)
1300 return t->data.val = CSA_FAIL_EXPLICIT;
1301 else
1302 return t->data.val = CSA_UNKNOWN;
1303 }
1304
1305 /* This CSA SRV record refers directly to our domain, so we check the value
1306 in the weight field to work out the domain's authorization. 0 and 1 are
1307 unauthorized; 3 means the client is authorized but we can't check the IP
1308 address in order to authenticate it, so we treat it as unknown; values
1309 greater than 3 are undefined. */
1310
1311 if (weight < 2) return t->data.val = CSA_FAIL_DOMAIN;
1312
1313 if (weight > 2) continue;
1314
1315 /* Weight == 2, which means the domain is authorized. We must check that the
1316 client's IP address is listed as one of the SRV target addresses. Save the
1317 target hostname then break to scan the additional data for its addresses. */
1318
1319 (void)dn_expand(dnsa.answer, dnsa.answer + dnsa.answerlen, p,
1320 (DN_EXPAND_ARG4_TYPE)target, sizeof(target));
1321
1322 DEBUG(D_acl) debug_printf("CSA target is %s\n", target);
1323
1324 break;
1325 }
1326
1327 /* If we didn't break the loop then no appropriate records were found. */
1328
1329 if (rr == NULL) return t->data.val = CSA_UNKNOWN;
1330
1331 /* Do not check addresses if the target is ".", in accordance with RFC 2782.
1332 A target of "." indicates there are no valid addresses, so the client cannot
1333 be authorized. (This is an odd configuration because weight=2 target=. is
1334 equivalent to weight=1, but we check for it in order to keep load off the
1335 root name servers.) Note that dn_expand() turns "." into "". */
1336
1337 if (Ustrcmp(target, "") == 0) return t->data.val = CSA_FAIL_NOADDR;
1338
1339 /* Scan the additional section of the CSA SRV reply for addresses belonging
1340 to the target. If the name server didn't return any additional data (e.g.
1341 because it does not fully support SRV records), we need to do another lookup
1342 to obtain the target addresses; otherwise we have a definitive result. */
1343
1344 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ADDITIONAL, target);
1345 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1346
1347 /* The DNS lookup type corresponds to the IP version used by the client. */
1348
1349 #if HAVE_IPV6
1350 if (Ustrchr(sender_host_address, ':') != NULL)
1351 type = T_AAAA;
1352 else
1353 #endif /* HAVE_IPV6 */
1354 type = T_A;
1355
1356
1357 #if HAVE_IPV6 && defined(SUPPORT_A6)
1358 DNS_LOOKUP_AGAIN:
1359 #endif
1360
1361 switch (dns_lookup(&dnsa, target, type, NULL))
1362 {
1363 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1364
1365 default:
1366 return t->data.val = CSA_DEFER_ADDR;
1367
1368 /* If the query succeeded, scan the addresses and return the result. */
1369
1370 case DNS_SUCCEED:
1371 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ANSWERS, target);
1372 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1373 /* else fall through */
1374
1375 /* If the target has no IP addresses, the client cannot have an authorized
1376 IP address. However, if the target site uses A6 records (not AAAA records)
1377 we have to do yet another lookup in order to check them. */
1378
1379 case DNS_NOMATCH:
1380 case DNS_NODATA:
1381
1382 #if HAVE_IPV6 && defined(SUPPORT_A6)
1383 if (type == T_AAAA) { type = T_A6; goto DNS_LOOKUP_AGAIN; }
1384 #endif
1385
1386 return t->data.val = CSA_FAIL_NOADDR;
1387 }
1388 }
1389
1390
1391
1392 /*************************************************
1393 * Handle verification (address & other) *
1394 *************************************************/
1395
1396 /* This function implements the "verify" condition. It is called when
1397 encountered in any ACL, because some tests are almost always permitted. Some
1398 just don't make sense, and always fail (for example, an attempt to test a host
1399 lookup for a non-TCP/IP message). Others are restricted to certain ACLs.
1400
1401 Arguments:
1402 where where called from
1403 addr the recipient address that the ACL is handling, or NULL
1404 arg the argument of "verify"
1405 user_msgptr pointer for user message
1406 log_msgptr pointer for log message
1407 basic_errno where to put verify errno
1408
1409 Returns: OK verification condition succeeded
1410 FAIL verification failed
1411 DEFER there was a problem verifying
1412 ERROR syntax error
1413 */
1414
1415 static int
1416 acl_verify(int where, address_item *addr, uschar *arg,
1417 uschar **user_msgptr, uschar **log_msgptr, int *basic_errno)
1418 {
1419 int sep = '/';
1420 int callout = -1;
1421 int callout_overall = -1;
1422 int callout_connect = -1;
1423 int verify_options = 0;
1424 int rc;
1425 BOOL verify_header_sender = FALSE;
1426 BOOL defer_ok = FALSE;
1427 BOOL callout_defer_ok = FALSE;
1428 BOOL no_details = FALSE;
1429 BOOL success_on_redirect = FALSE;
1430 address_item *sender_vaddr = NULL;
1431 uschar *verify_sender_address = NULL;
1432 uschar *pm_mailfrom = NULL;
1433 uschar *se_mailfrom = NULL;
1434
1435 /* Some of the verify items have slash-separated options; some do not. Diagnose
1436 an error if options are given for items that don't expect them. This code has
1437 now got very message. Refactoring to use a table would be a good idea one day.
1438 */
1439
1440 uschar *slash = Ustrchr(arg, '/');
1441 uschar *list = arg;
1442 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
1443
1444 if (ss == NULL) goto BAD_VERIFY;
1445
1446 /* Handle name/address consistency verification in a separate function. */
1447
1448 if (strcmpic(ss, US"reverse_host_lookup") == 0)
1449 {
1450 if (slash != NULL) goto NO_OPTIONS;
1451 if (sender_host_address == NULL) return OK;
1452 return acl_verify_reverse(user_msgptr, log_msgptr);
1453 }
1454
1455 /* TLS certificate verification is done at STARTTLS time; here we just
1456 test whether it was successful or not. (This is for optional verification; for
1457 mandatory verification, the connection doesn't last this long.) */
1458
1459 if (strcmpic(ss, US"certificate") == 0)
1460 {
1461 if (slash != NULL) goto NO_OPTIONS;
1462 if (tls_certificate_verified) return OK;
1463 *user_msgptr = US"no verified certificate";
1464 return FAIL;
1465 }
1466
1467 /* We can test the result of optional HELO verification that might have
1468 occurred earlier. If not, we can attempt the verification now. */
1469
1470 if (strcmpic(ss, US"helo") == 0)
1471 {
1472 if (slash != NULL) goto NO_OPTIONS;
1473 if (!helo_verified && !helo_verify_failed) smtp_verify_helo();
1474 return helo_verified? OK : FAIL;
1475 }
1476
1477 /* Do Client SMTP Authorization checks in a separate function, and turn the
1478 result code into user-friendly strings. */
1479
1480 if (strcmpic(ss, US"csa") == 0)
1481 {
1482 rc = acl_verify_csa(list);
1483 *log_msgptr = *user_msgptr = string_sprintf("client SMTP authorization %s",
1484 csa_reason_string[rc]);
1485 csa_status = csa_status_string[rc];
1486 DEBUG(D_acl) debug_printf("CSA result %s\n", csa_status);
1487 return csa_return_code[rc];
1488 }
1489
1490 /* Check that all relevant header lines have the correct syntax. If there is
1491 a syntax error, we return details of the error to the sender if configured to
1492 send out full details. (But a "message" setting on the ACL can override, as
1493 always). */
1494
1495 if (strcmpic(ss, US"header_syntax") == 0)
1496 {
1497 if (slash != NULL) goto NO_OPTIONS;
1498 if (where != ACL_WHERE_DATA && where != ACL_WHERE_NOTSMTP) goto WRONG_ACL;
1499 rc = verify_check_headers(log_msgptr);
1500 if (rc != OK && smtp_return_error_details && *log_msgptr != NULL)
1501 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1502 return rc;
1503 }
1504
1505 /* Check that no recipient of this message is "blind", that is, every envelope
1506 recipient must be mentioned in either To: or Cc:. */
1507
1508 if (strcmpic(ss, US"not_blind") == 0)
1509 {
1510 if (slash != NULL) goto NO_OPTIONS;
1511 if (where != ACL_WHERE_DATA && where != ACL_WHERE_NOTSMTP) goto WRONG_ACL;
1512 rc = verify_check_notblind();
1513 if (rc != OK)
1514 {
1515 *log_msgptr = string_sprintf("bcc recipient detected");
1516 if (smtp_return_error_details)
1517 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1518 }
1519 return rc;
1520 }
1521
1522 /* The remaining verification tests check recipient and sender addresses,
1523 either from the envelope or from the header. There are a number of
1524 slash-separated options that are common to all of them. */
1525
1526
1527 /* Check that there is at least one verifiable sender address in the relevant
1528 header lines. This can be followed by callout and defer options, just like
1529 sender and recipient. */
1530
1531 if (strcmpic(ss, US"header_sender") == 0)
1532 {
1533 if (where != ACL_WHERE_DATA && where != ACL_WHERE_NOTSMTP) goto WRONG_ACL;
1534 verify_header_sender = TRUE;
1535 }
1536
1537 /* Otherwise, first item in verify argument must be "sender" or "recipient".
1538 In the case of a sender, this can optionally be followed by an address to use
1539 in place of the actual sender (rare special-case requirement). */
1540
1541 else if (strncmpic(ss, US"sender", 6) == 0)
1542 {
1543 uschar *s = ss + 6;
1544 if (where > ACL_WHERE_NOTSMTP)
1545 {
1546 *log_msgptr = string_sprintf("cannot verify sender in ACL for %s "
1547 "(only possible for MAIL, RCPT, PREDATA, or DATA)",
1548 acl_wherenames[where]);
1549 return ERROR;
1550 }
1551 if (*s == 0)
1552 verify_sender_address = sender_address;
1553 else
1554 {
1555 while (isspace(*s)) s++;
1556 if (*s++ != '=') goto BAD_VERIFY;
1557 while (isspace(*s)) s++;
1558 verify_sender_address = string_copy(s);
1559 }
1560 }
1561 else
1562 {
1563 if (strcmpic(ss, US"recipient") != 0) goto BAD_VERIFY;
1564 if (addr == NULL)
1565 {
1566 *log_msgptr = string_sprintf("cannot verify recipient in ACL for %s "
1567 "(only possible for RCPT)", acl_wherenames[where]);
1568 return ERROR;
1569 }
1570 }
1571
1572 /* Remaining items are optional; they apply to sender and recipient
1573 verification, including "header sender" verification. */
1574
1575 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size))
1576 != NULL)
1577 {
1578 if (strcmpic(ss, US"defer_ok") == 0) defer_ok = TRUE;
1579 else if (strcmpic(ss, US"no_details") == 0) no_details = TRUE;
1580 else if (strcmpic(ss, US"success_on_redirect") == 0) success_on_redirect = TRUE;
1581
1582 /* These two old options are left for backwards compatibility */
1583
1584 else if (strcmpic(ss, US"callout_defer_ok") == 0)
1585 {
1586 callout_defer_ok = TRUE;
1587 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1588 }
1589
1590 else if (strcmpic(ss, US"check_postmaster") == 0)
1591 {
1592 pm_mailfrom = US"";
1593 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1594 }
1595
1596 /* The callout option has a number of sub-options, comma separated */
1597
1598 else if (strncmpic(ss, US"callout", 7) == 0)
1599 {
1600 callout = CALLOUT_TIMEOUT_DEFAULT;
1601 ss += 7;
1602 if (*ss != 0)
1603 {
1604 while (isspace(*ss)) ss++;
1605 if (*ss++ == '=')
1606 {
1607 int optsep = ',';
1608 uschar *opt;
1609 uschar buffer[256];
1610 while (isspace(*ss)) ss++;
1611
1612 /* This callout option handling code has become a mess as new options
1613 have been added in an ad hoc manner. It should be tidied up into some
1614 kind of table-driven thing. */
1615
1616 while ((opt = string_nextinlist(&ss, &optsep, buffer, sizeof(buffer)))
1617 != NULL)
1618 {
1619 if (strcmpic(opt, US"defer_ok") == 0) callout_defer_ok = TRUE;
1620 else if (strcmpic(opt, US"no_cache") == 0)
1621 verify_options |= vopt_callout_no_cache;
1622 else if (strcmpic(opt, US"random") == 0)
1623 verify_options |= vopt_callout_random;
1624 else if (strcmpic(opt, US"use_sender") == 0)
1625 verify_options |= vopt_callout_recipsender;
1626 else if (strcmpic(opt, US"use_postmaster") == 0)
1627 verify_options |= vopt_callout_recippmaster;
1628 else if (strcmpic(opt, US"postmaster") == 0) pm_mailfrom = US"";
1629 else if (strcmpic(opt, US"fullpostmaster") == 0)
1630 {
1631 pm_mailfrom = US"";
1632 verify_options |= vopt_callout_fullpm;
1633 }
1634
1635 else if (strncmpic(opt, US"mailfrom", 8) == 0)
1636 {
1637 if (!verify_header_sender)
1638 {
1639 *log_msgptr = string_sprintf("\"mailfrom\" is allowed as a "
1640 "callout option only for verify=header_sender (detected in ACL "
1641 "condition \"%s\")", arg);
1642 return ERROR;
1643 }
1644 opt += 8;
1645 while (isspace(*opt)) opt++;
1646 if (*opt++ != '=')
1647 {
1648 *log_msgptr = string_sprintf("'=' expected after "
1649 "\"mailfrom\" in ACL condition \"%s\"", arg);
1650 return ERROR;
1651 }
1652 while (isspace(*opt)) opt++;
1653 se_mailfrom = string_copy(opt);
1654 }
1655
1656 else if (strncmpic(opt, US"postmaster_mailfrom", 19) == 0)
1657 {
1658 opt += 19;
1659 while (isspace(*opt)) opt++;
1660 if (*opt++ != '=')
1661 {
1662 *log_msgptr = string_sprintf("'=' expected after "
1663 "\"postmaster_mailfrom\" in ACL condition \"%s\"", arg);
1664 return ERROR;
1665 }
1666 while (isspace(*opt)) opt++;
1667 pm_mailfrom = string_copy(opt);
1668 }
1669
1670 else if (strncmpic(opt, US"maxwait", 7) == 0)
1671 {
1672 opt += 7;
1673 while (isspace(*opt)) opt++;
1674 if (*opt++ != '=')
1675 {
1676 *log_msgptr = string_sprintf("'=' expected after \"maxwait\" in "
1677 "ACL condition \"%s\"", arg);
1678 return ERROR;
1679 }
1680 while (isspace(*opt)) opt++;
1681 callout_overall = readconf_readtime(opt, 0, FALSE);
1682 if (callout_overall < 0)
1683 {
1684 *log_msgptr = string_sprintf("bad time value in ACL condition "
1685 "\"verify %s\"", arg);
1686 return ERROR;
1687 }
1688 }
1689 else if (strncmpic(opt, US"connect", 7) == 0)
1690 {
1691 opt += 7;
1692 while (isspace(*opt)) opt++;
1693 if (*opt++ != '=')
1694 {
1695 *log_msgptr = string_sprintf("'=' expected after "
1696 "\"callout_overaall\" in ACL condition \"%s\"", arg);
1697 return ERROR;
1698 }
1699 while (isspace(*opt)) opt++;
1700 callout_connect = readconf_readtime(opt, 0, FALSE);
1701 if (callout_connect < 0)
1702 {
1703 *log_msgptr = string_sprintf("bad time value in ACL condition "
1704 "\"verify %s\"", arg);
1705 return ERROR;
1706 }
1707 }
1708 else /* Plain time is callout connect/command timeout */
1709 {
1710 callout = readconf_readtime(opt, 0, FALSE);
1711 if (callout < 0)
1712 {
1713 *log_msgptr = string_sprintf("bad time value in ACL condition "
1714 "\"verify %s\"", arg);
1715 return ERROR;
1716 }
1717 }
1718 }
1719 }
1720 else
1721 {
1722 *log_msgptr = string_sprintf("'=' expected after \"callout\" in "
1723 "ACL condition \"%s\"", arg);
1724 return ERROR;
1725 }
1726 }
1727 }
1728
1729 /* Option not recognized */
1730
1731 else
1732 {
1733 *log_msgptr = string_sprintf("unknown option \"%s\" in ACL "
1734 "condition \"verify %s\"", ss, arg);
1735 return ERROR;
1736 }
1737 }
1738
1739 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster)) ==
1740 (vopt_callout_recipsender|vopt_callout_recippmaster))
1741 {
1742 *log_msgptr = US"only one of use_sender and use_postmaster can be set "
1743 "for a recipient callout";
1744 return ERROR;
1745 }
1746
1747 /* Handle sender-in-header verification. Default the user message to the log
1748 message if giving out verification details. */
1749
1750 if (verify_header_sender)
1751 {
1752 int verrno;
1753 rc = verify_check_header_address(user_msgptr, log_msgptr, callout,
1754 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, verify_options,
1755 &verrno);
1756 if (rc != OK)
1757 {
1758 *basic_errno = verrno;
1759 if (smtp_return_error_details)
1760 {
1761 if (*user_msgptr == NULL && *log_msgptr != NULL)
1762 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1763 if (rc == DEFER) acl_temp_details = TRUE;
1764 }
1765 }
1766 }
1767
1768 /* Handle a sender address. The default is to verify *the* sender address, but
1769 optionally a different address can be given, for special requirements. If the
1770 address is empty, we are dealing with a bounce message that has no sender, so
1771 we cannot do any checking. If the real sender address gets rewritten during
1772 verification (e.g. DNS widening), set the flag to stop it being rewritten again
1773 during message reception.
1774
1775 A list of verified "sender" addresses is kept to try to avoid doing to much
1776 work repetitively when there are multiple recipients in a message and they all
1777 require sender verification. However, when callouts are involved, it gets too
1778 complicated because different recipients may require different callout options.
1779 Therefore, we always do a full sender verify when any kind of callout is
1780 specified. Caching elsewhere, for instance in the DNS resolver and in the
1781 callout handling, should ensure that this is not terribly inefficient. */
1782
1783 else if (verify_sender_address != NULL)
1784 {
1785 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster))
1786 != 0)
1787 {
1788 *log_msgptr = US"use_sender or use_postmaster cannot be used for a "
1789 "sender verify callout";
1790 return ERROR;
1791 }
1792
1793 sender_vaddr = verify_checked_sender(verify_sender_address);
1794 if (sender_vaddr != NULL && /* Previously checked */
1795 callout <= 0) /* No callout needed this time */
1796 {
1797 /* If the "routed" flag is set, it means that routing worked before, so
1798 this check can give OK (the saved return code value, if set, belongs to a
1799 callout that was done previously). If the "routed" flag is not set, routing
1800 must have failed, so we use the saved return code. */
1801
1802 if (testflag(sender_vaddr, af_verify_routed)) rc = OK; else
1803 {
1804 rc = sender_vaddr->special_action;
1805 *basic_errno = sender_vaddr->basic_errno;
1806 }
1807 HDEBUG(D_acl) debug_printf("using cached sender verify result\n");
1808 }
1809
1810 /* Do a new verification, and cache the result. The cache is used to avoid
1811 verifying the sender multiple times for multiple RCPTs when callouts are not
1812 specified (see comments above).
1813
1814 The cache is also used on failure to give details in response to the first
1815 RCPT that gets bounced for this reason. However, this can be suppressed by
1816 the no_details option, which sets the flag that says "this detail has already
1817 been sent". The cache normally contains just one address, but there may be
1818 more in esoteric circumstances. */
1819
1820 else
1821 {
1822 BOOL routed = TRUE;
1823 uschar *save_address_data = deliver_address_data;
1824
1825 sender_vaddr = deliver_make_addr(verify_sender_address, TRUE);
1826 if (no_details) setflag(sender_vaddr, af_sverify_told);
1827 if (verify_sender_address[0] != 0)
1828 {
1829 /* If this is the real sender address, save the unrewritten version
1830 for use later in receive. Otherwise, set a flag so that rewriting the
1831 sender in verify_address() does not update sender_address. */
1832
1833 if (verify_sender_address == sender_address)
1834 sender_address_unrewritten = sender_address;
1835 else
1836 verify_options |= vopt_fake_sender;
1837
1838 if (success_on_redirect)
1839 verify_options |= vopt_success_on_redirect;
1840
1841 /* The recipient, qualify, and expn options are never set in
1842 verify_options. */
1843
1844 rc = verify_address(sender_vaddr, NULL, verify_options, callout,
1845 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, &routed);
1846
1847 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
1848
1849 if (rc == OK)
1850 {
1851 if (Ustrcmp(sender_vaddr->address, verify_sender_address) != 0)
1852 {
1853 DEBUG(D_acl) debug_printf("sender %s verified ok as %s\n",
1854 verify_sender_address, sender_vaddr->address);
1855 }
1856 else
1857 {
1858 DEBUG(D_acl) debug_printf("sender %s verified ok\n",
1859 verify_sender_address);
1860 }
1861 }
1862 else *basic_errno = sender_vaddr->basic_errno;
1863 }
1864 else rc = OK; /* Null sender */
1865
1866 /* Cache the result code */
1867
1868 if (routed) setflag(sender_vaddr, af_verify_routed);
1869 if (callout > 0) setflag(sender_vaddr, af_verify_callout);
1870 sender_vaddr->special_action = rc;
1871 sender_vaddr->next = sender_verified_list;
1872 sender_verified_list = sender_vaddr;
1873
1874 /* Restore the recipient address data, which might have been clobbered by
1875 the sender verification. */
1876
1877 deliver_address_data = save_address_data;
1878 }
1879
1880 /* Put the sender address_data value into $sender_address_data */
1881
1882 sender_address_data = sender_vaddr->p.address_data;
1883 }
1884
1885 /* A recipient address just gets a straightforward verify; again we must handle
1886 the DEFER overrides. */
1887
1888 else
1889 {
1890 address_item addr2;
1891
1892 if (success_on_redirect)
1893 verify_options |= vopt_success_on_redirect;
1894
1895 /* We must use a copy of the address for verification, because it might
1896 get rewritten. */
1897
1898 addr2 = *addr;
1899 rc = verify_address(&addr2, NULL, verify_options|vopt_is_recipient, callout,
1900 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, NULL);
1901 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
1902
1903 *log_msgptr = addr2.message;
1904 *user_msgptr = (addr2.user_message != NULL)?
1905 addr2.user_message : addr2.message;
1906 *basic_errno = addr2.basic_errno;
1907
1908 /* Make $address_data visible */
1909 deliver_address_data = addr2.p.address_data;
1910 }
1911
1912 /* We have a result from the relevant test. Handle defer overrides first. */
1913
1914 if (rc == DEFER && (defer_ok ||
1915 (callout_defer_ok && *basic_errno == ERRNO_CALLOUTDEFER)))
1916 {
1917 HDEBUG(D_acl) debug_printf("verify defer overridden by %s\n",
1918 defer_ok? "defer_ok" : "callout_defer_ok");
1919 rc = OK;
1920 }
1921
1922 /* If we've failed a sender, set up a recipient message, and point
1923 sender_verified_failed to the address item that actually failed. */
1924
1925 if (rc != OK && verify_sender_address != NULL)
1926 {
1927 if (rc != DEFER)
1928 {
1929 *log_msgptr = *user_msgptr = US"Sender verify failed";
1930 }
1931 else if (*basic_errno != ERRNO_CALLOUTDEFER)
1932 {
1933 *log_msgptr = *user_msgptr = US"Could not complete sender verify";
1934 }
1935 else
1936 {
1937 *log_msgptr = US"Could not complete sender verify callout";
1938 *user_msgptr = smtp_return_error_details? sender_vaddr->user_message :
1939 *log_msgptr;
1940 }
1941
1942 sender_verified_failed = sender_vaddr;
1943 }
1944
1945 /* Verifying an address messes up the values of $domain and $local_part,
1946 so reset them before returning if this is a RCPT ACL. */
1947
1948 if (addr != NULL)
1949 {
1950 deliver_domain = addr->domain;
1951 deliver_localpart = addr->local_part;
1952 }
1953 return rc;
1954
1955 /* Syntax errors in the verify argument come here. */
1956
1957 BAD_VERIFY:
1958 *log_msgptr = string_sprintf("expected \"sender[=address]\", \"recipient\", "
1959 "\"helo\", \"header_syntax\", \"header_sender\" or "
1960 "\"reverse_host_lookup\" at start of ACL condition "
1961 "\"verify %s\"", arg);
1962 return ERROR;
1963
1964 /* Options supplied when not allowed come here */
1965
1966 NO_OPTIONS:
1967 *log_msgptr = string_sprintf("unexpected '/' found in \"%s\" "
1968 "(this verify item has no options)", arg);
1969 return ERROR;
1970
1971 /* Calls in the wrong ACL come here */
1972
1973 WRONG_ACL:
1974 *log_msgptr = string_sprintf("cannot check header contents in ACL for %s "
1975 "(only possible in ACL for DATA)", acl_wherenames[where]);
1976 return ERROR;
1977 }
1978
1979
1980
1981
1982 /*************************************************
1983 * Check argument for control= modifier *
1984 *************************************************/
1985
1986 /* Called from acl_check_condition() below
1987
1988 Arguments:
1989 arg the argument string for control=
1990 pptr set to point to the terminating character
1991 where which ACL we are in
1992 log_msgptr for error messages
1993
1994 Returns: CONTROL_xxx value
1995 */
1996
1997 static int
1998 decode_control(uschar *arg, uschar **pptr, int where, uschar **log_msgptr)
1999 {
2000 int len;
2001 control_def *d;
2002
2003 for (d = controls_list;
2004 d < controls_list + sizeof(controls_list)/sizeof(control_def);
2005 d++)
2006 {
2007 len = Ustrlen(d->name);
2008 if (Ustrncmp(d->name, arg, len) == 0) break;
2009 }
2010
2011 if (d >= controls_list + sizeof(controls_list)/sizeof(control_def) ||
2012 (arg[len] != 0 && (!d->has_option || arg[len] != '/')))
2013 {
2014 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
2015 return CONTROL_ERROR;
2016 }
2017
2018 *pptr = arg + len;
2019 return d->value;
2020 }
2021
2022
2023
2024 /*************************************************
2025 * Handle rate limiting *
2026 *************************************************/
2027
2028 /* Called by acl_check_condition() below to calculate the result
2029 of the ACL ratelimit condition.
2030
2031 Note that the return value might be slightly unexpected: if the
2032 sender's rate is above the limit then the result is OK. This is
2033 similar to the dnslists condition, and is so that you can write
2034 ACL clauses like: defer ratelimit = 15 / 1h
2035
2036 Arguments:
2037 arg the option string for ratelimit=
2038 where ACL_WHERE_xxxx indicating which ACL this is
2039 log_msgptr for error messages
2040
2041 Returns: OK - Sender's rate is above limit
2042 FAIL - Sender's rate is below limit
2043 DEFER - Problem opening ratelimit database
2044 ERROR - Syntax error in options.
2045 */
2046
2047 static int
2048 acl_ratelimit(uschar *arg, int where, uschar **log_msgptr)
2049 {
2050 double limit, period;
2051 uschar *ss, *key;
2052 int sep = '/';
2053 BOOL have_key = FALSE, leaky = FALSE, strict = FALSE;
2054 BOOL per_byte = FALSE, per_cmd = FALSE, per_conn = FALSE, per_mail = FALSE;
2055 int old_pool, rc;
2056 tree_node **anchor, *t;
2057 open_db dbblock, *dbm;
2058 dbdata_ratelimit *dbd;
2059 struct timeval tv;
2060
2061 /* Parse the first two options and record their values in expansion
2062 variables. These variables allow the configuration to have informative
2063 error messages based on rate limits obtained from a table lookup. */
2064
2065 /* First is the maximum number of messages per period and maximum burst
2066 size, which must be greater than or equal to zero. Zero is useful for
2067 rate measurement as opposed to rate limiting. */
2068
2069 sender_rate_limit = string_nextinlist(&arg, &sep, NULL, 0);
2070 if (sender_rate_limit == NULL)
2071 limit = -1.0;
2072 else
2073 {
2074 limit = Ustrtod(sender_rate_limit, &ss);
2075 if (tolower(*ss) == 'k') { limit *= 1024.0; ss++; }
2076 else if (tolower(*ss) == 'm') { limit *= 1024.0*1024.0; ss++; }
2077 else if (tolower(*ss) == 'g') { limit *= 1024.0*1024.0*1024.0; ss++; }
2078 }
2079 if (limit < 0.0 || *ss != 0)
2080 {
2081 *log_msgptr = string_sprintf("syntax error in argument for "
2082 "\"ratelimit\" condition: \"%s\" is not a positive number",
2083 sender_rate_limit);
2084 return ERROR;
2085 }
2086
2087 /* We use the rest of the argument list following the limit as the
2088 lookup key, because it doesn't make sense to use the same stored data
2089 if the period or options are different. */
2090
2091 key = arg;
2092
2093 /* Second is the rate measurement period and exponential smoothing time
2094 constant. This must be strictly greater than zero, because zero leads to
2095 run-time division errors. */
2096
2097 sender_rate_period = string_nextinlist(&arg, &sep, NULL, 0);
2098 if (sender_rate_period == NULL) period = -1.0;
2099 else period = readconf_readtime(sender_rate_period, 0, FALSE);
2100 if (period <= 0.0)
2101 {
2102 *log_msgptr = string_sprintf("syntax error in argument for "
2103 "\"ratelimit\" condition: \"%s\" is not a time value",
2104 sender_rate_period);
2105 return ERROR;
2106 }
2107
2108 /* Parse the other options. Should we check if the per_* options are being
2109 used in ACLs where they don't make sense, e.g. per_mail in the connect ACL? */
2110
2111 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2112 != NULL)
2113 {
2114 if (strcmpic(ss, US"leaky") == 0) leaky = TRUE;
2115 else if (strcmpic(ss, US"strict") == 0) strict = TRUE;
2116 else if (strcmpic(ss, US"per_byte") == 0) per_byte = TRUE;
2117 else if (strcmpic(ss, US"per_cmd") == 0) per_cmd = TRUE;
2118 else if (strcmpic(ss, US"per_conn") == 0) per_conn = TRUE;
2119 else if (strcmpic(ss, US"per_mail") == 0) per_mail = TRUE;
2120 else if (strcmpic(ss, US"per_rcpt") == 0) per_cmd = TRUE; /* alias */
2121 else have_key = TRUE;
2122 }
2123 if (leaky + strict > 1 || per_byte + per_cmd + per_conn + per_mail > 1)
2124 {
2125 *log_msgptr = US"conflicting options for \"ratelimit\" condition";
2126 return ERROR;
2127 }
2128
2129 /* Default option values */
2130 if (!strict) leaky = TRUE;
2131 if (!per_byte && !per_cmd && !per_conn) per_mail = TRUE;
2132
2133 /* If there is no explicit key, use the sender_host_address. If there is no
2134 sender_host_address (e.g. -bs or acl_not_smtp) then we simply omit it. */
2135
2136 if (!have_key && sender_host_address != NULL)
2137 key = string_sprintf("%s / %s", key, sender_host_address);
2138
2139 HDEBUG(D_acl) debug_printf("ratelimit condition limit=%.0f period=%.0f key=%s\n",
2140 limit, period, key);
2141
2142 /* See if we have already computed the rate by looking in the relevant tree. For
2143 per-connection rate limiting, store tree nodes and dbdata in the permanent pool
2144 so that they survive across resets. */
2145
2146 anchor = NULL;
2147 old_pool = store_pool;
2148
2149 if (per_conn)
2150 {
2151 anchor = &ratelimiters_conn;
2152 store_pool = POOL_PERM;
2153 }
2154 else if (per_mail || per_byte)
2155 anchor = &ratelimiters_mail;
2156 else if (per_cmd)
2157 anchor = &ratelimiters_cmd;
2158
2159 if (anchor != NULL && (t = tree_search(*anchor, key)) != NULL)
2160 {
2161 dbd = t->data.ptr;
2162 /* The following few lines duplicate some of the code below. */
2163 if (dbd->rate < limit) rc = FAIL;
2164 else rc = OK;
2165 store_pool = old_pool;
2166 sender_rate = string_sprintf("%.1f", dbd->rate);
2167 HDEBUG(D_acl)
2168 debug_printf("ratelimit found pre-computed rate %s\n", sender_rate);
2169 return rc;
2170 }
2171
2172 /* We aren't using a pre-computed rate, so get a previously recorded
2173 rate from the database, update it, and write it back. If there's no
2174 previous rate for this key, create one. */
2175
2176 dbm = dbfn_open(US"ratelimit", O_RDWR, &dbblock, TRUE);
2177 if (dbm == NULL)
2178 {
2179 store_pool = old_pool;
2180 sender_rate = NULL;
2181 HDEBUG(D_acl) debug_printf("ratelimit database not available\n");
2182 *log_msgptr = US"ratelimit database not available";
2183 return DEFER;
2184 }
2185 dbd = dbfn_read(dbm, key);
2186
2187 gettimeofday(&tv, NULL);
2188
2189 if (dbd == NULL)
2190 {
2191 HDEBUG(D_acl) debug_printf("ratelimit initializing new key's data\n");
2192 dbd = store_get(sizeof(dbdata_ratelimit));
2193 dbd->time_stamp = tv.tv_sec;
2194 dbd->time_usec = tv.tv_usec;
2195 dbd->rate = 0.0;
2196 }
2197 else
2198 {
2199 /* The smoothed rate is computed using an exponentially weighted moving
2200 average adjusted for variable sampling intervals. The standard EWMA for
2201 a fixed sampling interval is: f'(t) = (1 - a) * f(t) + a * f'(t - 1)
2202 where f() is the measured value and f'() is the smoothed value.
2203
2204 Old data decays out of the smoothed value exponentially, such that data n
2205 samples old is multiplied by a^n. The exponential decay time constant p
2206 is defined such that data p samples old is multiplied by 1/e, which means
2207 that a = exp(-1/p). We can maintain the same time constant for a variable
2208 sampling interval i by using a = exp(-i/p).
2209
2210 The rate we are measuring is messages per period, suitable for directly
2211 comparing with the limit. The average rate between now and the previous
2212 message is period / interval, which we feed into the EWMA as the sample.
2213
2214 It turns out that the number of messages required for the smoothed rate
2215 to reach the limit when they are sent in a burst is equal to the limit.
2216 This can be seen by analysing the value of the smoothed rate after N
2217 messages sent at even intervals. Let k = (1 - a) * p/i
2218
2219 rate_1 = (1 - a) * p/i + a * rate_0
2220 = k + a * rate_0
2221 rate_2 = k + a * rate_1
2222 = k + a * k + a^2 * rate_0
2223 rate_3 = k + a * k + a^2 * k + a^3 * rate_0
2224 rate_N = rate_0 * a^N + k * SUM(x=0..N-1)(a^x)
2225 = rate_0 * a^N + k * (1 - a^N) / (1 - a)
2226 = rate_0 * a^N + p/i * (1 - a^N)
2227
2228 When N is large, a^N -> 0 so rate_N -> p/i as desired.
2229
2230 rate_N = p/i + (rate_0 - p/i) * a^N
2231 a^N = (rate_N - p/i) / (rate_0 - p/i)
2232 N * -i/p = log((rate_N - p/i) / (rate_0 - p/i))
2233 N = p/i * log((rate_0 - p/i) / (rate_N - p/i))
2234
2235 Numerical analysis of the above equation, setting the computed rate to
2236 increase from rate_0 = 0 to rate_N = limit, shows that for large sending
2237 rates, p/i, the number of messages N = limit. So limit serves as both the
2238 maximum rate measured in messages per period, and the maximum number of
2239 messages that can be sent in a fast burst. */
2240
2241 double this_time = (double)tv.tv_sec
2242 + (double)tv.tv_usec / 1000000.0;
2243 double prev_time = (double)dbd->time_stamp
2244 + (double)dbd->time_usec / 1000000.0;
2245
2246 /* We must avoid division by zero, and deal gracefully with the clock going
2247 backwards. If we blunder ahead when time is in reverse then the computed
2248 rate will be bogus. To be safe we clamp interval to a very small number. */
2249
2250 double interval = this_time - prev_time <= 0.0 ? 1e-9
2251 : this_time - prev_time;
2252
2253 double i_over_p = interval / period;
2254 double a = exp(-i_over_p);
2255
2256 dbd->time_stamp = tv.tv_sec;
2257 dbd->time_usec = tv.tv_usec;
2258
2259 /* If we are measuring the rate in bytes per period, multiply the
2260 measured rate by the message size. If we don't know the message size
2261 then it's safe to just use a value of zero and let the recorded rate
2262 decay as if nothing happened. */
2263
2264 if (per_byte)
2265 dbd->rate = (message_size < 0 ? 0.0 : (double)message_size)
2266 * (1 - a) / i_over_p + a * dbd->rate;
2267 else if (per_cmd && where == ACL_WHERE_NOTSMTP)
2268 dbd->rate = (double)recipients_count
2269 * (1 - a) / i_over_p + a * dbd->rate;
2270 else
2271 dbd->rate = (1 - a) / i_over_p + a * dbd->rate;
2272 }
2273
2274 /* Clients sending at the limit are considered to be over the limit. This
2275 matters for edge cases such the first message sent by a client (which gets
2276 the initial rate of 0.0) when the rate limit is zero (i.e. the client should
2277 be completely blocked). */
2278
2279 if (dbd->rate < limit) rc = FAIL;
2280 else rc = OK;
2281
2282 /* Update the state if the rate is low or if we are being strict. If we
2283 are in leaky mode and the sender's rate is too high, we do not update
2284 the recorded rate in order to avoid an over-aggressive sender's retry
2285 rate preventing them from getting any email through. */
2286
2287 if (rc == FAIL || !leaky)
2288 dbfn_write(dbm, key, dbd, sizeof(dbdata_ratelimit));
2289 dbfn_close(dbm);
2290
2291 /* Store the result in the tree for future reference, if necessary. */
2292
2293 if (anchor != NULL)
2294 {
2295 t = store_get(sizeof(tree_node) + Ustrlen(key));
2296 t->data.ptr = dbd;
2297 Ustrcpy(t->name, key);
2298 (void)tree_insertnode(anchor, t);
2299 }
2300
2301 /* We create the formatted version of the sender's rate very late in
2302 order to ensure that it is done using the correct storage pool. */
2303
2304 store_pool = old_pool;
2305 sender_rate = string_sprintf("%.1f", dbd->rate);
2306
2307 HDEBUG(D_acl)
2308 debug_printf("ratelimit computed rate %s\n", sender_rate);
2309
2310 return rc;
2311 }
2312
2313
2314
2315 /*************************************************
2316 * Handle conditions/modifiers on an ACL item *
2317 *************************************************/
2318
2319 /* Called from acl_check() below.
2320
2321 Arguments:
2322 verb ACL verb
2323 cb ACL condition block - if NULL, result is OK
2324 where where called from
2325 addr the address being checked for RCPT, or NULL
2326 level the nesting level
2327 epp pointer to pass back TRUE if "endpass" encountered
2328 (applies only to "accept" and "discard")
2329 user_msgptr user message pointer
2330 log_msgptr log message pointer
2331 basic_errno pointer to where to put verify error
2332
2333 Returns: OK - all conditions are met
2334 DISCARD - an "acl" condition returned DISCARD - only allowed
2335 for "accept" or "discard" verbs
2336 FAIL - at least one condition fails
2337 FAIL_DROP - an "acl" condition returned FAIL_DROP
2338 DEFER - can't tell at the moment (typically, lookup defer,
2339 but can be temporary callout problem)
2340 ERROR - ERROR from nested ACL or expansion failure or other
2341 error
2342 */
2343
2344 static int
2345 acl_check_condition(int verb, acl_condition_block *cb, int where,
2346 address_item *addr, int level, BOOL *epp, uschar **user_msgptr,
2347 uschar **log_msgptr, int *basic_errno)
2348 {
2349 uschar *user_message = NULL;
2350 uschar *log_message = NULL;
2351 uschar *p;
2352 int rc = OK;
2353 #ifdef WITH_CONTENT_SCAN
2354 int sep = '/';
2355 #endif
2356
2357 for (; cb != NULL; cb = cb->next)
2358 {
2359 uschar *arg;
2360 int control_type;
2361
2362 /* The message and log_message items set up messages to be used in
2363 case of rejection. They are expanded later. */
2364
2365 if (cb->type == ACLC_MESSAGE)
2366 {
2367 user_message = cb->arg;
2368 continue;
2369 }
2370
2371 if (cb->type == ACLC_LOG_MESSAGE)
2372 {
2373 log_message = cb->arg;
2374 continue;
2375 }
2376
2377 /* The endpass "condition" just sets a flag to show it occurred. This is
2378 checked at compile time to be on an "accept" or "discard" item. */
2379
2380 if (cb->type == ACLC_ENDPASS)
2381 {
2382 *epp = TRUE;
2383 continue;
2384 }
2385
2386 /* For other conditions and modifiers, the argument is expanded now for some
2387 of them, but not for all, because expansion happens down in some lower level
2388 checking functions in some cases. */
2389
2390 if (cond_expand_at_top[cb->type])
2391 {
2392 arg = expand_string(cb->arg);
2393 if (arg == NULL)
2394 {
2395 if (expand_string_forcedfail) continue;
2396 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s",
2397 cb->arg, expand_string_message);
2398 return search_find_defer? DEFER : ERROR;
2399 }
2400 }
2401 else arg = cb->arg;
2402
2403 /* Show condition, and expanded condition if it's different */
2404
2405 HDEBUG(D_acl)
2406 {
2407 int lhswidth = 0;
2408 debug_printf("check %s%s %n",
2409 (!cond_modifiers[cb->type] && cb->u.negated)? "!":"",
2410 conditions[cb->type], &lhswidth);
2411
2412 if (cb->type == ACLC_SET)
2413 {
2414 int n = cb->u.varnumber;
2415 int t = (n < ACL_CVARS)? 'c' : 'm';
2416 if (n >= ACL_CVARS) n -= ACL_CVARS;
2417 debug_printf("acl_%c%d ", t, n);
2418 lhswidth += 7;
2419 }
2420
2421 debug_printf("= %s\n", cb->arg);
2422
2423 if (arg != cb->arg)
2424 debug_printf("%.*s= %s\n", lhswidth,
2425 US" ", CS arg);
2426 }
2427
2428 /* Check that this condition makes sense at this time */
2429
2430 if ((cond_forbids[cb->type] & (1 << where)) != 0)
2431 {
2432 *log_msgptr = string_sprintf("cannot %s %s condition in %s ACL",
2433 cond_modifiers[cb->type]? "use" : "test",
2434 conditions[cb->type], acl_wherenames[where]);
2435 return ERROR;
2436 }
2437
2438 /* Run the appropriate test for each condition, or take the appropriate
2439 action for the remaining modifiers. */
2440
2441 switch(cb->type)
2442 {
2443 case ACLC_ADD_HEADER:
2444 setup_header(arg);
2445 break;
2446
2447 /* A nested ACL that returns "discard" makes sense only for an "accept" or
2448 "discard" verb. */
2449
2450 case ACLC_ACL:
2451 rc = acl_check_internal(where, addr, arg, level+1, user_msgptr, log_msgptr);
2452 if (rc == DISCARD && verb != ACL_ACCEPT && verb != ACL_DISCARD)
2453 {
2454 *log_msgptr = string_sprintf("nested ACL returned \"discard\" for "
2455 "\"%s\" command (only allowed with \"accept\" or \"discard\")",
2456 verbs[verb]);
2457 return ERROR;
2458 }
2459 break;
2460
2461 case ACLC_AUTHENTICATED:
2462 rc = (sender_host_authenticated == NULL)? FAIL :
2463 match_isinlist(sender_host_authenticated, &arg, 0, NULL, NULL, MCL_STRING,
2464 TRUE, NULL);
2465 break;
2466
2467 #ifdef EXPERIMENTAL_BRIGHTMAIL
2468 case ACLC_BMI_OPTIN:
2469 {
2470 int old_pool = store_pool;
2471 store_pool = POOL_PERM;
2472 bmi_current_optin = string_copy(arg);
2473 store_pool = old_pool;
2474 }
2475 break;
2476 #endif
2477
2478 case ACLC_CONDITION:
2479 if (Ustrspn(arg, "0123456789") == Ustrlen(arg)) /* Digits, or empty */
2480 rc = (Uatoi(arg) == 0)? FAIL : OK;
2481 else
2482 rc = (strcmpic(arg, US"no") == 0 ||
2483 strcmpic(arg, US"false") == 0)? FAIL :
2484 (strcmpic(arg, US"yes") == 0 ||
2485 strcmpic(arg, US"true") == 0)? OK : DEFER;
2486 if (rc == DEFER)
2487 *log_msgptr = string_sprintf("invalid \"condition\" value \"%s\"", arg);
2488 break;
2489
2490 case ACLC_CONTROL:
2491 control_type = decode_control(arg, &p, where, log_msgptr);
2492
2493 /* Check if this control makes sense at this time */
2494
2495 if ((control_forbids[control_type] & (1 << where)) != 0)
2496 {
2497 *log_msgptr = string_sprintf("cannot use \"control=%s\" in %s ACL",
2498 controls[control_type], acl_wherenames[where]);
2499 return ERROR;
2500 }
2501
2502 switch(control_type)
2503 {
2504 case CONTROL_AUTH_UNADVERTISED:
2505 allow_auth_unadvertised = TRUE;
2506 break;
2507
2508 #ifdef EXPERIMENTAL_BRIGHTMAIL
2509 case CONTROL_BMI_RUN:
2510 bmi_run = 1;
2511 break;
2512 #endif
2513
2514 #ifdef EXPERIMENTAL_DOMAINKEYS
2515 case CONTROL_DK_VERIFY:
2516 dk_do_verify = 1;
2517 break;
2518 #endif
2519
2520 case CONTROL_ERROR:
2521 return ERROR;
2522
2523 case CONTROL_CASEFUL_LOCAL_PART:
2524 deliver_localpart = addr->cc_local_part;
2525 break;
2526
2527 case CONTROL_CASELOWER_LOCAL_PART:
2528 deliver_localpart = addr->lc_local_part;
2529 break;
2530
2531 case CONTROL_ENFORCE_SYNC:
2532 smtp_enforce_sync = TRUE;
2533 break;
2534
2535 case CONTROL_NO_ENFORCE_SYNC:
2536 smtp_enforce_sync = FALSE;
2537 break;
2538
2539 #ifdef WITH_CONTENT_SCAN
2540 case CONTROL_NO_MBOX_UNSPOOL:
2541 no_mbox_unspool = TRUE;
2542 break;
2543 #endif
2544
2545 case CONTROL_NO_MULTILINE:
2546 no_multiline_responses = TRUE;
2547 break;
2548
2549 case CONTROL_FAKEDEFER:
2550 case CONTROL_FAKEREJECT:
2551 fake_response = (control_type == CONTROL_FAKEDEFER) ? DEFER : FAIL;
2552 if (*p == '/')
2553 {
2554 uschar *pp = p + 1;
2555 while (*pp != 0) pp++;
2556 fake_response_text = expand_string(string_copyn(p+1, pp-p-1));
2557 p = pp;
2558 }
2559 else
2560 {
2561 /* Explicitly reset to default string */
2562 fake_response_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).";
2563 }
2564 break;
2565
2566 case CONTROL_FREEZE:
2567 deliver_freeze = TRUE;
2568 deliver_frozen_at = time(NULL);
2569 freeze_tell = freeze_tell_config; /* Reset to configured value */
2570 if (Ustrncmp(p, "/no_tell", 8) == 0)
2571 {
2572 p += 8;
2573 freeze_tell = NULL;
2574 }
2575 if (*p != 0)
2576 {
2577 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
2578 return ERROR;
2579 }
2580 break;
2581
2582 case CONTROL_QUEUE_ONLY:
2583 queue_only_policy = TRUE;
2584 break;
2585
2586 case CONTROL_SUBMISSION:
2587 originator_name = US"";
2588 submission_mode = TRUE;
2589 while (*p == '/')
2590 {
2591 if (Ustrncmp(p, "/sender_retain", 14) == 0)
2592 {
2593 p += 14;
2594 active_local_sender_retain = TRUE;
2595 active_local_from_check = FALSE;
2596 }
2597 else if (Ustrncmp(p, "/domain=", 8) == 0)
2598 {
2599 uschar *pp = p + 8;
2600 while (*pp != 0 && *pp != '/') pp++;
2601 submission_domain = string_copyn(p+8, pp-p-8);
2602 p = pp;
2603 }
2604 /* The name= option must be last, because it swallows the rest of
2605 the string. */
2606 else if (Ustrncmp(p, "/name=", 6) == 0)
2607 {
2608 uschar *pp = p + 6;
2609 while (*pp != 0) pp++;
2610 submission_name = string_copy(parse_fix_phrase(p+6, pp-p-6,
2611 big_buffer, big_buffer_size));
2612 p = pp;
2613 }
2614 else break;
2615 }
2616 if (*p != 0)
2617 {
2618 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
2619 return ERROR;
2620 }
2621 break;
2622
2623 case CONTROL_SUPPRESS_LOCAL_FIXUPS:
2624 suppress_local_fixups = TRUE;
2625 break;
2626 }
2627 break;
2628
2629 #ifdef WITH_CONTENT_SCAN
2630 case ACLC_DECODE:
2631 rc = mime_decode(&arg);
2632 break;
2633 #endif
2634
2635 case ACLC_DELAY:
2636 {
2637 int delay = readconf_readtime(arg, 0, FALSE);
2638 if (delay < 0)
2639 {
2640 *log_msgptr = string_sprintf("syntax error in argument for \"delay\" "
2641 "modifier: \"%s\" is not a time value", arg);
2642 return ERROR;
2643 }
2644 else
2645 {
2646 HDEBUG(D_acl) debug_printf("delay modifier requests %d-second delay\n",
2647 delay);
2648 if (host_checking)
2649 {
2650 HDEBUG(D_acl)
2651 debug_printf("delay skipped in -bh checking mode\n");
2652 }
2653
2654 /* It appears to be impossible to detect that a TCP/IP connection has
2655 gone away without reading from it. This means that we cannot shorten
2656 the delay below if the client goes away, because we cannot discover
2657 that the client has closed its end of the connection. (The connection
2658 is actually in a half-closed state, waiting for the server to close its
2659 end.) It would be nice to be able to detect this state, so that the
2660 Exim process is not held up unnecessarily. However, it seems that we
2661 can't. The poll() function does not do the right thing, and in any case
2662 it is not always available.
2663
2664 NOTE: If ever this state of affairs changes, remember that we may be
2665 dealing with stdin/stdout here, in addition to TCP/IP connections.
2666 Whatever is done must work in both cases. To detected the stdin/stdout
2667 case, check for smtp_in or smtp_out being NULL. */
2668
2669 else
2670 {
2671 while (delay > 0) delay = sleep(delay);
2672 }
2673 }
2674 }
2675 break;
2676
2677 #ifdef WITH_OLD_DEMIME
2678 case ACLC_DEMIME:
2679 rc = demime(&arg);
2680 break;
2681 #endif
2682
2683 #ifdef EXPERIMENTAL_DOMAINKEYS
2684 case ACLC_DK_DOMAIN_SOURCE:
2685 if (dk_verify_block == NULL) { rc = FAIL; break; };
2686 /* check header source of domain against given string */
2687 switch (dk_verify_block->address_source) {
2688 case DK_EXIM_ADDRESS_FROM_FROM:
2689 rc = match_isinlist(US"from", &arg, 0, NULL,
2690 NULL, MCL_STRING, TRUE, NULL);
2691 break;
2692 case DK_EXIM_ADDRESS_FROM_SENDER:
2693 rc = match_isinlist(US"sender", &arg, 0, NULL,
2694 NULL, MCL_STRING, TRUE, NULL);
2695 break;
2696 case DK_EXIM_ADDRESS_NONE:
2697 rc = match_isinlist(US"none", &arg, 0, NULL,
2698 NULL, MCL_STRING, TRUE, NULL);
2699 break;
2700 }
2701 break;
2702
2703 case ACLC_DK_POLICY:
2704 if (dk_verify_block == NULL) { rc = FAIL; break; };
2705 /* check policy against given string, default FAIL */
2706 rc = FAIL;
2707 if (dk_verify_block->signsall)
2708 rc = match_isinlist(US"signsall", &arg, 0, NULL,
2709 NULL, MCL_STRING, TRUE, NULL);
2710 if (dk_verify_block->testing)
2711 rc = match_isinlist(US"testing", &arg, 0, NULL,
2712 NULL, MCL_STRING, TRUE, NULL);
2713 break;
2714
2715 case ACLC_DK_SENDER_DOMAINS:
2716 if (dk_verify_block == NULL) { rc = FAIL; break; };
2717 if (dk_verify_block->domain != NULL)
2718 rc = match_isinlist(dk_verify_block->domain, &arg, 0, &domainlist_anchor,
2719 NULL, MCL_DOMAIN, TRUE, NULL);
2720 else rc = FAIL;
2721 break;
2722
2723 case ACLC_DK_SENDER_LOCAL_PARTS:
2724 if (dk_verify_block == NULL) { rc = FAIL; break; };
2725 if (dk_verify_block->local_part != NULL)
2726 rc = match_isinlist(dk_verify_block->local_part, &arg, 0, &localpartlist_anchor,
2727 NULL, MCL_LOCALPART, TRUE, NULL);
2728 else rc = FAIL;
2729 break;
2730
2731 case ACLC_DK_SENDERS:
2732 if (dk_verify_block == NULL) { rc = FAIL; break; };
2733 if (dk_verify_block->address != NULL)
2734 rc = match_address_list(dk_verify_block->address, TRUE, TRUE, &arg, NULL, -1, 0, NULL);
2735 else rc = FAIL;
2736 break;
2737
2738 case ACLC_DK_STATUS:
2739 if (dk_verify_block == NULL) { rc = FAIL; break; };
2740 if (dk_verify_block->result > 0) {
2741 switch(dk_verify_block->result) {
2742 case DK_EXIM_RESULT_BAD_FORMAT:
2743 rc = match_isinlist(US"bad format", &arg, 0, NULL,
2744 NULL, MCL_STRING, TRUE, NULL);
2745 break;
2746 case DK_EXIM_RESULT_NO_KEY:
2747 rc = match_isinlist(US"no key", &arg, 0, NULL,
2748 NULL, MCL_STRING, TRUE, NULL);
2749 break;
2750 case DK_EXIM_RESULT_NO_SIGNATURE:
2751 rc = match_isinlist(US"no signature", &arg, 0, NULL,
2752 NULL, MCL_STRING, TRUE, NULL);
2753 break;
2754 case DK_EXIM_RESULT_REVOKED:
2755 rc = match_isinlist(US"revoked", &arg, 0, NULL,
2756 NULL, MCL_STRING, TRUE, NULL);
2757 break;
2758 case DK_EXIM_RESULT_NON_PARTICIPANT:
2759 rc = match_isinlist(US"non-participant", &arg, 0, NULL,
2760 NULL, MCL_STRING, TRUE, NULL);
2761 break;
2762 case DK_EXIM_RESULT_GOOD:
2763 rc = match_isinlist(US"good", &arg, 0, NULL,
2764 NULL, MCL_STRING, TRUE, NULL);
2765 break;
2766 case DK_EXIM_RESULT_BAD:
2767 rc = match_isinlist(US"bad", &arg, 0, NULL,
2768 NULL, MCL_STRING, TRUE, NULL);
2769 break;
2770 }
2771 }
2772 break;
2773 #endif
2774
2775 case ACLC_DNSLISTS:
2776 rc = verify_check_dnsbl(&arg);
2777 break;
2778
2779 case ACLC_DOMAINS:
2780 rc = match_isinlist(addr->domain, &arg, 0, &domainlist_anchor,
2781 addr->domain_cache, MCL_DOMAIN, TRUE, &deliver_domain_data);
2782 break;
2783
2784 /* The value in tls_cipher is the full cipher name, for example,
2785 TLSv1:DES-CBC3-SHA:168, whereas the values to test for are just the
2786 cipher names such as DES-CBC3-SHA. But program defensively. We don't know
2787 what may in practice come out of the SSL library - which at the time of
2788 writing is poorly documented. */
2789
2790 case ACLC_ENCRYPTED:
2791 if (tls_cipher == NULL) rc = FAIL; else
2792 {
2793 uschar *endcipher = NULL;
2794 uschar *cipher = Ustrchr(tls_cipher, ':');
2795 if (cipher == NULL) cipher = tls_cipher; else
2796 {
2797 endcipher = Ustrchr(++cipher, ':');
2798 if (endcipher != NULL) *endcipher = 0;
2799 }
2800 rc = match_isinlist(cipher, &arg, 0, NULL, NULL, MCL_STRING, TRUE, NULL);
2801 if (endcipher != NULL) *endcipher = ':';
2802 }
2803 break;
2804
2805 /* Use verify_check_this_host() instead of verify_check_host() so that
2806 we can pass over &host_data to catch any looked up data. Once it has been
2807 set, it retains its value so that it's still there if another ACL verb
2808 comes through here and uses the cache. However, we must put it into
2809 permanent store in case it is also expected to be used in a subsequent
2810 message in the same SMTP connection. */
2811
2812 case ACLC_HOSTS:
2813 rc = verify_check_this_host(&arg, sender_host_cache, NULL,
2814 (sender_host_address == NULL)? US"" : sender_host_address, &host_data);
2815 if (host_data != NULL) host_data = string_copy_malloc(host_data);
2816 break;
2817
2818 case ACLC_LOCAL_PARTS:
2819 rc = match_isinlist(addr->cc_local_part, &arg, 0,
2820 &localpartlist_anchor, addr->localpart_cache, MCL_LOCALPART, TRUE,
2821 &deliver_localpart_data);
2822 break;
2823
2824 case ACLC_LOGWRITE:
2825 {
2826 int logbits = 0;
2827 uschar *s = arg;
2828 if (*s == ':')
2829 {
2830 s++;
2831 while (*s != ':')
2832 {
2833 if (Ustrncmp(s, "main", 4) == 0)
2834 { logbits |= LOG_MAIN; s += 4; }
2835 else if (Ustrncmp(s, "panic", 5) == 0)
2836 { logbits |= LOG_PANIC; s += 5; }
2837 else if (Ustrncmp(s, "reject", 6) == 0)
2838 { logbits |= LOG_REJECT; s += 6; }
2839 else
2840 {
2841 logbits = LOG_MAIN|LOG_PANIC;
2842 s = string_sprintf(":unknown log name in \"%s\" in "
2843 "\"logwrite\" in %s ACL", arg, acl_wherenames[where]);
2844 }
2845 if (*s == ',') s++;
2846 }
2847 s++;
2848 }
2849 while (isspace(*s)) s++;
2850 if (logbits == 0) logbits = LOG_MAIN;
2851 log_write(0, logbits, "%s", string_printing(s));
2852 }
2853 break;
2854
2855 #ifdef WITH_CONTENT_SCAN
2856 case ACLC_MALWARE:
2857 {
2858 /* Seperate the regular expression and any optional parameters. */
2859 uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size);
2860 /* Run the malware backend. */
2861 rc = malware(&ss);
2862 /* Modify return code based upon the existance of options. */
2863 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2864 != NULL) {
2865 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
2866 {
2867 /* FAIL so that the message is passed to the next ACL */
2868 rc = FAIL;
2869 }
2870 }
2871 }
2872 break;
2873
2874 case ACLC_MIME_REGEX:
2875 rc = mime_regex(&arg);
2876 break;
2877 #endif
2878
2879 case ACLC_RATELIMIT:
2880 rc = acl_ratelimit(arg, where, log_msgptr);
2881 break;
2882
2883 case ACLC_RECIPIENTS:
2884 rc = match_address_list(addr->address, TRUE, TRUE, &arg, NULL, -1, 0,
2885 &recipient_data);
2886 break;
2887
2888 #ifdef WITH_CONTENT_SCAN
2889 case ACLC_REGEX:
2890 rc = regex(&arg);
2891 break;
2892 #endif
2893
2894 case ACLC_SENDER_DOMAINS:
2895 {
2896 uschar *sdomain;
2897 sdomain = Ustrrchr(sender_address, '@');
2898 sdomain = (sdomain == NULL)? US"" : sdomain + 1;
2899 rc = match_isinlist(sdomain, &arg, 0, &domainlist_anchor,
2900 sender_domain_cache, MCL_DOMAIN, TRUE, NULL);
2901 }
2902 break;
2903
2904 case ACLC_SENDERS:
2905 rc = match_address_list(sender_address, TRUE, TRUE, &arg,
2906 sender_address_cache, -1, 0, &sender_data);
2907 break;
2908
2909 /* Connection variables must persist forever */
2910
2911 case ACLC_SET:
2912 {
2913 int old_pool = store_pool;
2914 if (cb->u.varnumber < ACL_CVARS) store_pool = POOL_PERM;
2915 acl_var[cb->u.varnumber] = string_copy(arg);
2916 store_pool = old_pool;
2917 }
2918 break;
2919
2920 #ifdef WITH_CONTENT_SCAN
2921 case ACLC_SPAM:
2922 {
2923 /* Seperate the regular expression and any optional parameters. */
2924 uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size);
2925 /* Run the spam backend. */
2926 rc = spam(&ss);
2927 /* Modify return code based upon the existance of options. */
2928 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2929 != NULL) {
2930 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
2931 {
2932 /* FAIL so that the message is passed to the next ACL */
2933 rc = FAIL;
2934 }
2935 }
2936 }
2937 break;
2938 #endif
2939
2940 #ifdef EXPERIMENTAL_SPF
2941 case ACLC_SPF:
2942 rc = spf_process(&arg, sender_address);
2943 break;
2944 #endif
2945
2946 /* If the verb is WARN, discard any user message from verification, because
2947 such messages are SMTP responses, not header additions. The latter come
2948 only from explicit "message" modifiers. However, put the user message into
2949 $acl_verify_message so it can be used in subsequent conditions or modifiers
2950 (until something changes it). */
2951
2952 case ACLC_VERIFY:
2953 rc = acl_verify(where, addr, arg, user_msgptr, log_msgptr, basic_errno);
2954 acl_verify_message = *user_msgptr;
2955 if (verb == ACL_WARN) *user_msgptr = NULL;
2956 break;
2957
2958 default:
2959 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown "
2960 "condition %d", cb->type);
2961 break;
2962 }
2963
2964 /* If a condition was negated, invert OK/FAIL. */
2965
2966 if (!cond_modifiers[cb->type] && cb->u.negated)
2967 {
2968 if (rc == OK) rc = FAIL;
2969 else if (rc == FAIL || rc == FAIL_DROP) rc = OK;
2970 }
2971
2972 if (rc != OK) break; /* Conditions loop */
2973 }
2974
2975
2976 /* If the result is the one for which "message" and/or "log_message" are used,
2977 handle the values of these options. Most verbs have but a single return for
2978 which the messages are relevant, but for "discard", it's useful to have the log
2979 message both when it succeeds and when it fails. Also, for an "accept" that
2980 appears in a QUIT ACL, we want to handle the user message. Since only "accept"
2981 and "warn" are permitted in that ACL, we don't need to test the verb.
2982
2983 These modifiers act in different ways:
2984
2985 "message" is a user message that will be included in an SMTP response. Unless
2986 it is empty, it overrides any previously set user message.
2987
2988 "log_message" is a non-user message, and it adds to any existing non-user
2989 message that is already set.
2990
2991 If there isn't a log message set, we make it the same as the user message. */
2992
2993 if (((rc == FAIL_DROP)? FAIL : rc) == msgcond[verb] ||
2994 (verb == ACL_DISCARD && rc == OK) ||
2995 (where == ACL_WHERE_QUIT))
2996 {
2997 uschar *expmessage;
2998
2999 /* If the verb is "warn", messages generated by conditions (verification or
3000 nested ACLs) are discarded. Only messages specified at this level are used.
3001 However, the value of an existing message is available in $acl_verify_message
3002 during expansions. */
3003
3004 uschar *old_user_msgptr = *user_msgptr;
3005 uschar *old_log_msgptr = (*log_msgptr != NULL)? *log_msgptr : old_user_msgptr;
3006
3007 if (verb == ACL_WARN) *log_msgptr = *user_msgptr = NULL;
3008
3009 if (user_message != NULL)
3010 {
3011 acl_verify_message = old_user_msgptr;
3012 expmessage = expand_string(user_message);
3013 if (expmessage == NULL)
3014 {
3015 if (!expand_string_forcedfail)
3016 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
3017 user_message, expand_string_message);
3018 }
3019 else if (expmessage[0] != 0) *user_msgptr = expmessage;
3020 }
3021
3022 if (log_message != NULL)
3023 {
3024 acl_verify_message = old_log_msgptr;
3025 expmessage = expand_string(log_message);
3026 if (expmessage == NULL)
3027 {
3028 if (!expand_string_forcedfail)
3029 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
3030 log_message, expand_string_message);
3031 }
3032 else if (expmessage[0] != 0)
3033 {
3034 *log_msgptr = (*log_msgptr == NULL)? expmessage :
3035 string_sprintf("%s: %s", expmessage, *log_msgptr);
3036 }
3037 }
3038
3039 /* If no log message, default it to the user message */
3040
3041 if (*log_msgptr == NULL) *log_msgptr = *user_msgptr;
3042 }
3043
3044 acl_verify_message = NULL;
3045 return rc;
3046 }
3047
3048
3049
3050
3051
3052 /*************************************************
3053 * Get line from a literal ACL *
3054 *************************************************/
3055
3056 /* This function is passed to acl_read() in order to extract individual lines
3057 of a literal ACL, which we access via static pointers. We can destroy the
3058 contents because this is called only once (the compiled ACL is remembered).
3059
3060 This code is intended to treat the data in the same way as lines in the main
3061 Exim configuration file. That is:
3062
3063 . Leading spaces are ignored.
3064
3065 . A \ at the end of a line is a continuation - trailing spaces after the \
3066 are permitted (this is because I don't believe in making invisible things
3067 significant). Leading spaces on the continued part of a line are ignored.
3068
3069 . Physical lines starting (significantly) with # are totally ignored, and
3070 may appear within a sequence of backslash-continued lines.
3071
3072 . Blank lines are ignored, but will end a sequence of continuations.
3073
3074 Arguments: none
3075 Returns: a pointer to the next line
3076 */
3077
3078
3079 static uschar *acl_text; /* Current pointer in the text */
3080 static uschar *acl_text_end; /* Points one past the terminating '0' */
3081
3082
3083 static uschar *
3084 acl_getline(void)
3085 {
3086 uschar *yield;
3087
3088 /* This loop handles leading blank lines and comments. */
3089
3090 for(;;)
3091 {
3092 while (isspace(*acl_text)) acl_text++; /* Leading spaces/empty lines */
3093 if (*acl_text == 0) return NULL; /* No more data */
3094 yield = acl_text; /* Potential data line */
3095
3096 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3097
3098 /* If we hit the end before a newline, we have the whole logical line. If
3099 it's a comment, there's no more data to be given. Otherwise, yield it. */
3100
3101 if (*acl_text == 0) return (*yield == '#')? NULL : yield;
3102
3103 /* After reaching a newline, end this loop if the physical line does not
3104 start with '#'. If it does, it's a comment, and the loop continues. */
3105
3106 if (*yield != '#') break;
3107 }
3108
3109 /* This loop handles continuations. We know we have some real data, ending in
3110 newline. See if there is a continuation marker at the end (ignoring trailing
3111 white space). We know that *yield is not white space, so no need to test for
3112 cont > yield in the backwards scanning loop. */
3113
3114 for(;;)
3115 {
3116 uschar *cont;
3117 for (cont = acl_text - 1; isspace(*cont); cont--);
3118
3119 /* If no continuation follows, we are done. Mark the end of the line and
3120 return it. */
3121
3122 if (*cont != '\\')
3123 {
3124 *acl_text++ = 0;
3125 return yield;
3126 }
3127
3128 /* We have encountered a continuation. Skip over whitespace at the start of
3129 the next line, and indeed the whole of the next line or lines if they are
3130 comment lines. */
3131
3132 for (;;)
3133 {
3134 while (*(++acl_text) == ' ' || *acl_text == '\t');
3135 if (*acl_text != '#') break;
3136 while (*(++acl_text) != 0 && *acl_text != '\n');
3137 }
3138
3139 /* We have the start of a continuation line. Move all the rest of the data
3140 to join onto the previous line, and then find its end. If the end is not a
3141 newline, we are done. Otherwise loop to look for another continuation. */
3142
3143 memmove(cont, acl_text, acl_text_end - acl_text);
3144 acl_text_end -= acl_text - cont;
3145 acl_text = cont;
3146 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3147 if (*acl_text == 0) return yield;
3148 }
3149
3150 /* Control does not reach here */
3151 }
3152
3153
3154
3155
3156
3157 /*************************************************
3158 * Check access using an ACL *
3159 *************************************************/
3160
3161 /* This function is called from address_check. It may recurse via
3162 acl_check_condition() - hence the use of a level to stop looping. The ACL is
3163 passed as a string which is expanded. A forced failure implies no access check
3164 is required. If the result is a single word, it is taken as the name of an ACL
3165 which is sought in the global ACL tree. Otherwise, it is taken as literal ACL
3166 text, complete with newlines, and parsed as such. In both cases, the ACL check
3167 is then run. This function uses an auxiliary function for acl_read() to call
3168 for reading individual lines of a literal ACL. This is acl_getline(), which
3169 appears immediately above.
3170
3171 Arguments:
3172 where where called from
3173 addr address item when called from RCPT; otherwise NULL
3174 s the input string; NULL is the same as an empty ACL => DENY
3175 level the nesting level
3176 user_msgptr where to put a user error (for SMTP response)
3177 log_msgptr where to put a logging message (not for SMTP response)
3178
3179 Returns: OK access is granted
3180 DISCARD access is apparently granted...
3181 FAIL access is denied
3182 FAIL_DROP access is denied; drop the connection
3183 DEFER can't tell at the moment
3184 ERROR disaster
3185 */
3186
3187 static int
3188 acl_check_internal(int where, address_item *addr, uschar *s, int level,
3189 uschar **user_msgptr, uschar **log_msgptr)
3190 {
3191 int fd = -1;
3192 acl_block *acl = NULL;
3193 uschar *acl_name = US"inline ACL";
3194 uschar *ss;
3195
3196 /* Catch configuration loops */
3197
3198 if (level > 20)
3199 {
3200 *log_msgptr = US"ACL nested too deep: possible loop";
3201 return ERROR;
3202 }
3203
3204 if (s == NULL)
3205 {
3206 HDEBUG(D_acl) debug_printf("ACL is NULL: implicit DENY\n");
3207 return FAIL;
3208 }
3209
3210 /* At top level, we expand the incoming string. At lower levels, it has already
3211 been expanded as part of condition processing. */
3212
3213 if (level == 0)
3214 {
3215 ss = expand_string(s);
3216 if (ss == NULL)
3217 {
3218 if (expand_string_forcedfail) return OK;
3219 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s", s,
3220 expand_string_message);
3221 return ERROR;
3222 }
3223 }
3224 else ss = s;
3225
3226 while (isspace(*ss))ss++;
3227
3228 /* If we can't find a named ACL, the default is to parse it as an inline one.
3229 (Unless it begins with a slash; non-existent files give rise to an error.) */
3230
3231 acl_text = ss;
3232
3233 /* Handle the case of a string that does not contain any spaces. Look for a
3234 named ACL among those read from the configuration, or a previously read file.
3235 It is possible that the pointer to the ACL is NULL if the configuration
3236 contains a name with no data. If not found, and the text begins with '/',
3237 read an ACL from a file, and save it so it can be re-used. */
3238
3239 if (Ustrchr(ss, ' ') == NULL)
3240 {
3241 tree_node *t = tree_search(acl_anchor, ss);
3242 if (t != NULL)
3243 {
3244 acl = (acl_block *)(t->data.ptr);
3245 if (acl == NULL)
3246 {
3247 HDEBUG(D_acl) debug_printf("ACL \"%s\" is empty: implicit DENY\n", ss);
3248 return FAIL;
3249 }
3250 acl_name = string_sprintf("ACL \"%s\"", ss);
3251 HDEBUG(D_acl) debug_printf("using ACL \"%s\"\n", ss);
3252 }
3253
3254 else if (*ss == '/')
3255 {
3256 struct stat statbuf;
3257 fd = Uopen(ss, O_RDONLY, 0);
3258 if (fd < 0)
3259 {
3260 *log_msgptr = string_sprintf("failed to open ACL file \"%s\": %s", ss,
3261 strerror(errno));
3262 return ERROR;
3263 }
3264
3265 if (fstat(fd, &statbuf) != 0)
3266 {
3267 *log_msgptr = string_sprintf("failed to fstat ACL file \"%s\": %s", ss,
3268 strerror(errno));
3269 return ERROR;
3270 }
3271
3272 acl_text = store_get(statbuf.st_size + 1);
3273 acl_text_end = acl_text + statbuf.st_size + 1;
3274
3275 if (read(fd, acl_text, statbuf.st_size) != statbuf.st_size)
3276 {
3277 *log_msgptr = string_sprintf("failed to read ACL file \"%s\": %s",
3278 ss, strerror(errno));
3279 return ERROR;
3280 }
3281 acl_text[statbuf.st_size] = 0;
3282 (void)close(fd);
3283
3284 acl_name = string_sprintf("ACL \"%s\"", ss);
3285 HDEBUG(D_acl) debug_printf("read ACL from file %s\n", ss);
3286 }
3287 }
3288
3289 /* Parse an ACL that is still in text form. If it came from a file, remember it
3290 in the ACL tree, having read it into the POOL_PERM store pool so that it
3291 persists between multiple messages. */
3292
3293 if (acl == NULL)
3294 {
3295 int old_pool = store_pool;
3296 if (fd >= 0) store_pool = POOL_PERM;
3297 acl = acl_read(acl_getline, log_msgptr);
3298 store_pool = old_pool;
3299 if (acl == NULL && *log_msgptr != NULL) return ERROR;
3300 if (fd >= 0)
3301 {
3302 tree_node *t = store_get_perm(sizeof(tree_node) + Ustrlen(ss));
3303 Ustrcpy(t->name, ss);
3304 t->data.ptr = acl;
3305 (void)tree_insertnode(&acl_anchor, t);
3306 }
3307 }
3308
3309 /* Now we have an ACL to use. It's possible it may be NULL. */
3310
3311 while (acl != NULL)
3312 {
3313 int cond;
3314 int basic_errno = 0;
3315 BOOL endpass_seen = FALSE;
3316
3317 *log_msgptr = *user_msgptr = NULL;
3318 acl_temp_details = FALSE;
3319
3320 if (where == ACL_WHERE_QUIT &&
3321 acl->verb != ACL_ACCEPT &&
3322 acl->verb != ACL_WARN)
3323 {
3324 *log_msgptr = string_sprintf("\"%s\" is not allowed in a QUIT ACL",
3325 verbs[acl->verb]);
3326 return ERROR;
3327 }
3328
3329 HDEBUG(D_acl) debug_printf("processing \"%s\"\n", verbs[acl->verb]);
3330
3331 /* Clear out any search error message from a previous check before testing
3332 this condition. */
3333
3334 search_error_message = NULL;
3335 cond = acl_check_condition(acl->verb, acl->condition, where, addr, level,
3336 &endpass_seen, user_msgptr, log_msgptr, &basic_errno);
3337
3338 /* Handle special returns: DEFER causes a return except on a WARN verb;
3339 ERROR always causes a return. */
3340
3341 switch (cond)
3342 {
3343 case DEFER:
3344 HDEBUG(D_acl) debug_printf("%s: condition test deferred\n", verbs[acl->verb]);
3345 if (basic_errno != ERRNO_CALLOUTDEFER)
3346 {
3347 if (search_error_message != NULL && *search_error_message != 0)
3348 *log_msgptr = search_error_message;
3349 if (smtp_return_error_details) acl_temp_details = TRUE;
3350 }
3351 else
3352 {
3353 acl_temp_details = TRUE;
3354 }
3355 if (acl->verb != ACL_WARN) return DEFER;
3356 break;
3357
3358 default: /* Paranoia */
3359 case ERROR:
3360 HDEBUG(D_acl) debug_printf("%s: condition test error\n", verbs[acl->verb]);
3361 return ERROR;
3362
3363 case OK:
3364 HDEBUG(D_acl) debug_printf("%s: condition test succeeded\n",
3365 verbs[acl->verb]);
3366 break;
3367
3368 case FAIL:
3369 HDEBUG(D_acl) debug_printf("%s: condition test failed\n", verbs[acl->verb]);
3370 break;
3371
3372 /* DISCARD and DROP can happen only from a nested ACL condition, and
3373 DISCARD can happen only for an "accept" or "discard" verb. */
3374
3375 case DISCARD:
3376 HDEBUG(D_acl) debug_printf("%s: condition test yielded \"discard\"\n",
3377 verbs[acl->verb]);
3378 break;
3379
3380 case FAIL_DROP:
3381 HDEBUG(D_acl) debug_printf("%s: condition test yielded \"drop\"\n",
3382 verbs[acl->verb]);
3383 break;
3384 }
3385
3386 /* At this point, cond for most verbs is either OK or FAIL or (as a result of
3387 a nested ACL condition) FAIL_DROP. However, for WARN, cond may be DEFER, and
3388 for ACCEPT and DISCARD, it may be DISCARD after a nested ACL call. */
3389
3390 switch(acl->verb)
3391 {
3392 case ACL_ACCEPT:
3393 if (cond == OK || cond == DISCARD) return cond;
3394 if (endpass_seen)
3395 {
3396 HDEBUG(D_acl) debug_printf("accept: endpass encountered - denying access\n");
3397 return cond;
3398 }
3399 break;
3400
3401 case ACL_DEFER:
3402 if (cond == OK)
3403 {
3404 acl_temp_details = TRUE;
3405 return DEFER;
3406 }
3407 break;
3408
3409 case ACL_DENY:
3410 if (cond == OK) return FAIL;
3411 break;
3412
3413 case ACL_DISCARD:
3414 if (cond == OK || cond == DISCARD) return DISCARD;
3415 if (endpass_seen)
3416 {
3417 HDEBUG(D_acl) debug_printf("discard: endpass encountered - denying access\n");
3418 return cond;
3419 }
3420 break;
3421
3422 case ACL_DROP:
3423 if (cond == OK) return FAIL_DROP;
3424 break;
3425
3426 case ACL_REQUIRE:
3427 if (cond != OK) return cond;
3428 break;
3429
3430 case ACL_WARN:
3431 if (cond == OK)
3432 acl_warn(where, *user_msgptr, *log_msgptr);
3433 else if (cond == DEFER && (log_extra_selector & LX_acl_warn_skipped) != 0)
3434 log_write(0, LOG_MAIN, "%s Warning: ACL \"warn\" statement skipped: "
3435 "condition test deferred%s%s", host_and_ident(TRUE),
3436 (*log_msgptr == NULL)? US"" : US": ",
3437 (*log_msgptr == NULL)? US"" : *log_msgptr);
3438 *log_msgptr = *user_msgptr = NULL; /* In case implicit DENY follows */
3439 break;
3440
3441 default:
3442 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown verb %d",
3443 acl->verb);
3444 break;
3445 }
3446
3447 /* Pass to the next ACL item */
3448
3449 acl = acl->next;
3450 }
3451
3452 /* We have reached the end of the ACL. This is an implicit DENY. */
3453
3454 HDEBUG(D_acl) debug_printf("end of %s: implicit DENY\n", acl_name);
3455 return FAIL;
3456 }
3457
3458
3459 /*************************************************
3460 * Check access using an ACL *
3461 *************************************************/
3462
3463 /* This is the external interface for ACL checks. It sets up an address and the
3464 expansions for $domain and $local_part when called after RCPT, then calls
3465 acl_check_internal() to do the actual work.
3466
3467 Arguments:
3468 where ACL_WHERE_xxxx indicating where called from
3469 recipient RCPT address for RCPT check, else NULL
3470 s the input string; NULL is the same as an empty ACL => DENY
3471 user_msgptr where to put a user error (for SMTP response)
3472 log_msgptr where to put a logging message (not for SMTP response)
3473
3474 Returns: OK access is granted by an ACCEPT verb
3475 DISCARD access is granted by a DISCARD verb
3476 FAIL access is denied
3477 FAIL_DROP access is denied; drop the connection
3478 DEFER can't tell at the moment
3479 ERROR disaster
3480 */
3481
3482 int
3483 acl_check(int where, uschar *recipient, uschar *s, uschar **user_msgptr,
3484 uschar **log_msgptr)
3485 {
3486 int rc;
3487 address_item adb;
3488 address_item *addr = NULL;
3489
3490 *user_msgptr = *log_msgptr = NULL;
3491 sender_verified_failed = NULL;
3492 ratelimiters_cmd = NULL;
3493
3494 if (where == ACL_WHERE_RCPT)
3495 {
3496 adb = address_defaults;
3497 addr = &adb;
3498 addr->address = recipient;
3499 if (deliver_split_address(addr) == DEFER)
3500 {
3501 *log_msgptr = US"defer in percent_hack_domains check";
3502 return DEFER;
3503 }
3504 deliver_domain = addr->domain;
3505 deliver_localpart = addr->local_part;
3506 }
3507
3508 rc = acl_check_internal(where, addr, s, 0, user_msgptr, log_msgptr);
3509
3510 deliver_domain = deliver_localpart = deliver_address_data =
3511 sender_address_data = NULL;
3512
3513 /* A DISCARD response is permitted only for message ACLs, excluding the PREDATA
3514 ACL, which is really in the middle of an SMTP command. */
3515
3516 if (rc == DISCARD)
3517 {
3518 if (where > ACL_WHERE_NOTSMTP || where == ACL_WHERE_PREDATA)
3519 {
3520 log_write(0, LOG_MAIN|LOG_PANIC, "\"discard\" verb not allowed in %s "
3521 "ACL", acl_wherenames[where]);
3522 return ERROR;
3523 }
3524 return DISCARD;
3525 }
3526
3527 /* A DROP response is not permitted from MAILAUTH */
3528
3529 if (rc == FAIL_DROP && where == ACL_WHERE_MAILAUTH)
3530 {
3531 log_write(0, LOG_MAIN|LOG_PANIC, "\"drop\" verb not allowed in %s "
3532 "ACL", acl_wherenames[where]);
3533 return ERROR;
3534 }
3535
3536 /* Before giving an error response, take a look at the length of any user
3537 message, and split it up into multiple lines if possible. */
3538
3539 if (rc != OK && *user_msgptr != NULL && Ustrlen(*user_msgptr) > 75)
3540 {
3541 uschar *s = *user_msgptr = string_copy(*user_msgptr);
3542 uschar *ss = s;
3543
3544 for (;;)
3545 {
3546 int i = 0;
3547 while (i < 75 && *ss != 0 && *ss != '\n') ss++, i++;
3548 if (*ss == 0) break;
3549 if (*ss == '\n')
3550 s = ++ss;
3551 else
3552 {
3553 uschar *t = ss + 1;
3554 uschar *tt = NULL;
3555 while (--t > s + 35)
3556 {
3557 if (*t == ' ')
3558 {
3559 if (t[-1] == ':') { tt = t; break; }
3560 if (tt == NULL) tt = t;
3561 }
3562 }
3563
3564 if (tt == NULL) /* Can't split behind - try ahead */
3565 {
3566 t = ss + 1;
3567 while (*t != 0)
3568 {
3569 if (*t == ' ' || *t == '\n')
3570 { tt = t; break; }
3571 t++;
3572 }
3573 }
3574
3575 if (tt == NULL) break; /* Can't find anywhere to split */
3576 *tt = '\n';
3577 s = ss = tt+1;
3578 }
3579 }
3580 }
3581
3582 return rc;
3583 }
3584
3585 /* End of acl.c */