Tweak the ACL variable name code to require either a digit or an
[exim.git] / src / src / acl.c
1 /* $Cambridge: exim/src/src/acl.c,v 1.65 2006/09/19 14:31:06 ph10 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 (1<<ACL_WHERE_NOTSMTP_START)),
330
331 (1<<ACL_WHERE_NOTSMTP)| /* authenticated */
332 (1<<ACL_WHERE_NOTSMTP_START)|
333 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO),
334
335 #ifdef EXPERIMENTAL_BRIGHTMAIL
336 (1<<ACL_WHERE_AUTH)| /* bmi_optin */
337 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
338 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_MIME)|
339 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
340 (1<<ACL_WHERE_MAILAUTH)|
341 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
342 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_PREDATA)|
343 (1<<ACL_WHERE_NOTSMTP_START),
344 #endif
345
346 0, /* condition */
347
348 /* Certain types of control are always allowed, so we let it through
349 always and check in the control processing itself. */
350
351 0, /* control */
352
353 #ifdef WITH_CONTENT_SCAN
354 (unsigned int)
355 ~(1<<ACL_WHERE_MIME), /* decode */
356 #endif
357
358 0, /* delay */
359
360 #ifdef WITH_OLD_DEMIME
361 (unsigned int)
362 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)), /* demime */
363 #endif
364
365 #ifdef EXPERIMENTAL_DOMAINKEYS
366 (1<<ACL_WHERE_AUTH)| /* dk_domain_source */
367 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
368 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
369 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
370 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
371 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
372 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_NOTSMTP_START),
373
374 (1<<ACL_WHERE_AUTH)| /* dk_policy */
375 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
376 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
377 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
378 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
379 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
380 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_NOTSMTP_START),
381
382 (1<<ACL_WHERE_AUTH)| /* dk_sender_domains */
383 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
384 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
385 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
386 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
387 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
388 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_NOTSMTP_START),
389
390 (1<<ACL_WHERE_AUTH)| /* dk_sender_local_parts */
391 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
392 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
393 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
394 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
395 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
396 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_NOTSMTP_START),
397
398 (1<<ACL_WHERE_AUTH)| /* dk_senders */
399 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
400 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
401 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
402 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
403 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
404 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_NOTSMTP_START),
405
406 (1<<ACL_WHERE_AUTH)| /* dk_status */
407 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
408 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
409 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
410 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
411 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
412 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_NOTSMTP_START),
413 #endif
414
415 (1<<ACL_WHERE_NOTSMTP)| /* dnslists */
416 (1<<ACL_WHERE_NOTSMTP_START),
417
418 (unsigned int)
419 ~(1<<ACL_WHERE_RCPT), /* domains */
420
421 (1<<ACL_WHERE_NOTSMTP)| /* encrypted */
422 (1<<ACL_WHERE_CONNECT)|
423 (1<<ACL_WHERE_NOTSMTP_START)|
424 (1<<ACL_WHERE_HELO),
425
426 0, /* endpass */
427
428 (1<<ACL_WHERE_NOTSMTP)| /* hosts */
429 (1<<ACL_WHERE_NOTSMTP_START),
430
431 (unsigned int)
432 ~(1<<ACL_WHERE_RCPT), /* local_parts */
433
434 0, /* log_message */
435
436 0, /* logwrite */
437
438 #ifdef WITH_CONTENT_SCAN
439 (unsigned int)
440 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)), /* malware */
441 #endif
442
443 0, /* message */
444
445 #ifdef WITH_CONTENT_SCAN
446 (unsigned int)
447 ~(1<<ACL_WHERE_MIME), /* mime_regex */
448 #endif
449
450 0, /* ratelimit */
451
452 (unsigned int)
453 ~(1<<ACL_WHERE_RCPT), /* recipients */
454
455 #ifdef WITH_CONTENT_SCAN
456 (unsigned int)
457 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* regex */
458 (1<<ACL_WHERE_MIME)),
459 #endif
460
461 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* sender_domains */
462 (1<<ACL_WHERE_HELO)|
463 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
464 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
465 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
466
467 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* senders */
468 (1<<ACL_WHERE_HELO)|
469 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
470 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
471 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
472
473 0, /* set */
474
475 #ifdef WITH_CONTENT_SCAN
476 (unsigned int)
477 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)), /* spam */
478 #endif
479
480 #ifdef EXPERIMENTAL_SPF
481 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* spf */
482 (1<<ACL_WHERE_HELO)|
483 (1<<ACL_WHERE_MAILAUTH)|
484 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
485 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY)|
486 (1<<ACL_WHERE_NOTSMTP)|
487 (1<<ACL_WHERE_NOTSMTP_START),
488 #endif
489
490 /* Certain types of verify are always allowed, so we let it through
491 always and check in the verify function itself */
492
493 0 /* verify */
494 };
495
496
497 /* Bit map vector of which controls are not allowed at certain times. For
498 each control, there's a bitmap of dis-allowed times. For some, it is easier to
499 specify the negation of a small number of allowed times. */
500
501 static unsigned int control_forbids[] = {
502 (unsigned int)
503 ~((1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)), /* allow_auth_unadvertised */
504
505 #ifdef EXPERIMENTAL_BRIGHTMAIL
506 0, /* bmi_run */
507 #endif
508
509 #ifdef EXPERIMENTAL_DOMAINKEYS
510 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* dk_verify */
511 (1<<ACL_WHERE_NOTSMTP_START),
512 #endif
513
514 0, /* error */
515
516 (unsigned int)
517 ~(1<<ACL_WHERE_RCPT), /* caseful_local_part */
518
519 (unsigned int)
520 ~(1<<ACL_WHERE_RCPT), /* caselower_local_part */
521
522 (1<<ACL_WHERE_NOTSMTP)| /* enforce_sync */
523 (1<<ACL_WHERE_NOTSMTP_START),
524
525 (1<<ACL_WHERE_NOTSMTP)| /* no_enforce_sync */
526 (1<<ACL_WHERE_NOTSMTP_START),
527
528 (unsigned int)
529 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* freeze */
530 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
531 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)),
532
533 (unsigned int)
534 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* queue_only */
535 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
536 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)),
537
538 (unsigned int)
539 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* submission */
540 (1<<ACL_WHERE_PREDATA)),
541
542 (unsigned int)
543 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* suppress_local_fixups */
544 (1<<ACL_WHERE_PREDATA)|
545 (1<<ACL_WHERE_NOTSMTP_START)),
546
547 #ifdef WITH_CONTENT_SCAN
548 (unsigned int)
549 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* no_mbox_unspool */
550 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
551 (1<<ACL_WHERE_MIME)),
552 #endif
553
554 (unsigned int)
555 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakedefer */
556 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
557 (1<<ACL_WHERE_MIME)),
558
559 (unsigned int)
560 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakereject */
561 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
562 (1<<ACL_WHERE_MIME)),
563
564 (1<<ACL_WHERE_NOTSMTP)| /* no_multiline */
565 (1<<ACL_WHERE_NOTSMTP_START)
566 };
567
568 /* Structure listing various control arguments, with their characteristics. */
569
570 typedef struct control_def {
571 uschar *name;
572 int value; /* CONTROL_xxx value */
573 BOOL has_option; /* Has /option(s) following */
574 } control_def;
575
576 static control_def controls_list[] = {
577 { US"allow_auth_unadvertised", CONTROL_AUTH_UNADVERTISED, FALSE },
578 #ifdef EXPERIMENTAL_BRIGHTMAIL
579 { US"bmi_run", CONTROL_BMI_RUN, FALSE },
580 #endif
581 #ifdef EXPERIMENTAL_DOMAINKEYS
582 { US"dk_verify", CONTROL_DK_VERIFY, FALSE },
583 #endif
584 { US"caseful_local_part", CONTROL_CASEFUL_LOCAL_PART, FALSE },
585 { US"caselower_local_part", CONTROL_CASELOWER_LOCAL_PART, FALSE },
586 { US"enforce_sync", CONTROL_ENFORCE_SYNC, FALSE },
587 { US"freeze", CONTROL_FREEZE, TRUE },
588 { US"no_enforce_sync", CONTROL_NO_ENFORCE_SYNC, FALSE },
589 { US"no_multiline_responses", CONTROL_NO_MULTILINE, FALSE },
590 { US"queue_only", CONTROL_QUEUE_ONLY, FALSE },
591 #ifdef WITH_CONTENT_SCAN
592 { US"no_mbox_unspool", CONTROL_NO_MBOX_UNSPOOL, FALSE },
593 #endif
594 { US"fakedefer", CONTROL_FAKEDEFER, TRUE },
595 { US"fakereject", CONTROL_FAKEREJECT, TRUE },
596 { US"submission", CONTROL_SUBMISSION, TRUE },
597 { US"suppress_local_fixups", CONTROL_SUPPRESS_LOCAL_FIXUPS, FALSE }
598 };
599
600 /* Support data structures for Client SMTP Authorization. acl_verify_csa()
601 caches its result in a tree to avoid repeated DNS queries. The result is an
602 integer code which is used as an index into the following tables of
603 explanatory strings and verification return codes. */
604
605 static tree_node *csa_cache = NULL;
606
607 enum { CSA_UNKNOWN, CSA_OK, CSA_DEFER_SRV, CSA_DEFER_ADDR,
608 CSA_FAIL_EXPLICIT, CSA_FAIL_DOMAIN, CSA_FAIL_NOADDR, CSA_FAIL_MISMATCH };
609
610 /* The acl_verify_csa() return code is translated into an acl_verify() return
611 code using the following table. It is OK unless the client is definitely not
612 authorized. This is because CSA is supposed to be optional for sending sites,
613 so recipients should not be too strict about checking it - especially because
614 DNS problems are quite likely to occur. It's possible to use $csa_status in
615 further ACL conditions to distinguish ok, unknown, and defer if required, but
616 the aim is to make the usual configuration simple. */
617
618 static int csa_return_code[] = {
619 OK, OK, OK, OK,
620 FAIL, FAIL, FAIL, FAIL
621 };
622
623 static uschar *csa_status_string[] = {
624 US"unknown", US"ok", US"defer", US"defer",
625 US"fail", US"fail", US"fail", US"fail"
626 };
627
628 static uschar *csa_reason_string[] = {
629 US"unknown",
630 US"ok",
631 US"deferred (SRV lookup failed)",
632 US"deferred (target address lookup failed)",
633 US"failed (explicit authorization required)",
634 US"failed (host name not authorized)",
635 US"failed (no authorized addresses)",
636 US"failed (client address mismatch)"
637 };
638
639 /* Enable recursion between acl_check_internal() and acl_check_condition() */
640
641 static int acl_check_internal(int, address_item *, uschar *, int, uschar **,
642 uschar **);
643
644
645 /*************************************************
646 * Pick out name from list *
647 *************************************************/
648
649 /* Use a binary chop method
650
651 Arguments:
652 name name to find
653 list list of names
654 end size of list
655
656 Returns: offset in list, or -1 if not found
657 */
658
659 static int
660 acl_checkname(uschar *name, uschar **list, int end)
661 {
662 int start = 0;
663
664 while (start < end)
665 {
666 int mid = (start + end)/2;
667 int c = Ustrcmp(name, list[mid]);
668 if (c == 0) return mid;
669 if (c < 0) end = mid; else start = mid + 1;
670 }
671
672 return -1;
673 }
674
675
676 /*************************************************
677 * Read and parse one ACL *
678 *************************************************/
679
680 /* This function is called both from readconf in order to parse the ACLs in the
681 configuration file, and also when an ACL is encountered dynamically (e.g. as
682 the result of an expansion). It is given a function to call in order to
683 retrieve the lines of the ACL. This function handles skipping comments and
684 blank lines (where relevant).
685
686 Arguments:
687 func function to get next line of ACL
688 error where to put an error message
689
690 Returns: pointer to ACL, or NULL
691 NULL can be legal (empty ACL); in this case error will be NULL
692 */
693
694 acl_block *
695 acl_read(uschar *(*func)(void), uschar **error)
696 {
697 acl_block *yield = NULL;
698 acl_block **lastp = &yield;
699 acl_block *this = NULL;
700 acl_condition_block *cond;
701 acl_condition_block **condp = NULL;
702 uschar *s;
703
704 *error = NULL;
705
706 while ((s = (*func)()) != NULL)
707 {
708 int v, c;
709 BOOL negated = FALSE;
710 uschar *saveline = s;
711 uschar name[64];
712
713 /* Conditions (but not verbs) are allowed to be negated by an initial
714 exclamation mark. */
715
716 while (isspace(*s)) s++;
717 if (*s == '!')
718 {
719 negated = TRUE;
720 s++;
721 }
722
723 /* Read the name of a verb or a condition, or the start of a new ACL, which
724 can be started by a name, or by a macro definition. */
725
726 s = readconf_readname(name, sizeof(name), s);
727 if (*s == ':' || (isupper(name[0]) && *s == '=')) return yield;
728
729 /* If a verb is unrecognized, it may be another condition or modifier that
730 continues the previous verb. */
731
732 v = acl_checkname(name, verbs, sizeof(verbs)/sizeof(char *));
733 if (v < 0)
734 {
735 if (this == NULL)
736 {
737 *error = string_sprintf("unknown ACL verb \"%s\" in \"%s\"", name,
738 saveline);
739 return NULL;
740 }
741 }
742
743 /* New verb */
744
745 else
746 {
747 if (negated)
748 {
749 *error = string_sprintf("malformed ACL line \"%s\"", saveline);
750 return NULL;
751 }
752 this = store_get(sizeof(acl_block));
753 *lastp = this;
754 lastp = &(this->next);
755 this->next = NULL;
756 this->verb = v;
757 this->condition = NULL;
758 condp = &(this->condition);
759 if (*s == 0) continue; /* No condition on this line */
760 if (*s == '!')
761 {
762 negated = TRUE;
763 s++;
764 }
765 s = readconf_readname(name, sizeof(name), s); /* Condition name */
766 }
767
768 /* Handle a condition or modifier. */
769
770 c = acl_checkname(name, conditions, sizeof(conditions)/sizeof(char *));
771 if (c < 0)
772 {
773 *error = string_sprintf("unknown ACL condition/modifier in \"%s\"",
774 saveline);
775 return NULL;
776 }
777
778 /* The modifiers may not be negated */
779
780 if (negated && cond_modifiers[c])
781 {
782 *error = string_sprintf("ACL error: negation is not allowed with "
783 "\"%s\"", conditions[c]);
784 return NULL;
785 }
786
787 /* ENDPASS may occur only with ACCEPT or DISCARD. */
788
789 if (c == ACLC_ENDPASS &&
790 this->verb != ACL_ACCEPT &&
791 this->verb != ACL_DISCARD)
792 {
793 *error = string_sprintf("ACL error: \"%s\" is not allowed with \"%s\"",
794 conditions[c], verbs[this->verb]);
795 return NULL;
796 }
797
798 cond = store_get(sizeof(acl_condition_block));
799 cond->next = NULL;
800 cond->type = c;
801 cond->u.negated = negated;
802
803 *condp = cond;
804 condp = &(cond->next);
805
806 /* The "set" modifier is different in that its argument is "name=value"
807 rather than just a value, and we can check the validity of the name, which
808 gives us a variable name to insert into the data block. The original ACL
809 variable names were acl_c0 ... acl_c9 and acl_m0 ... acl_m9. This was
810 extended to 20 of each type, but after that people successfully argued for
811 arbitrary names. In the new scheme, the names must start with acl_c or acl_m.
812 After that, we allow alphanumerics and underscores, but the first character
813 after c or m must be a digit or an underscore. This retains backwards
814 compatibility. */
815
816 if (c == ACLC_SET)
817 {
818 uschar *endptr;
819
820 if (Ustrncmp(s, "acl_c", 5) != 0 &&
821 Ustrncmp(s, "acl_m", 5) != 0)
822 {
823 *error = string_sprintf("invalid variable name after \"set\" in ACL "
824 "modifier \"set %s\" (must start \"acl_c\" or \"acl_m\")", s);
825 return NULL;
826 }
827
828 endptr = s + 5;
829 if (!isdigit(*endptr) && *endptr != '_')
830 {
831 *error = string_sprintf("invalid variable name after \"set\" in ACL "
832 "modifier \"set %s\" (digit or underscore must follow acl_c or acl_m)",
833 s);
834 return NULL;
835 }
836
837 while (*endptr != 0 && *endptr != '=' && !isspace(*endptr))
838 {
839 if (!isalnum(*endptr) && *endptr != '_')
840 {
841 *error = string_sprintf("invalid character \"%c\" in variable name "
842 "in ACL modifier \"set %s\"", *endptr, s);
843 return NULL;
844 }
845 endptr++;
846 }
847
848 cond->u.varname = string_copyn(s + 4, endptr - s - 4);
849 s = endptr;
850 while (isspace(*s)) s++;
851 }
852
853 /* For "set", we are now positioned for the data. For the others, only
854 "endpass" has no data */
855
856 if (c != ACLC_ENDPASS)
857 {
858 if (*s++ != '=')
859 {
860 *error = string_sprintf("\"=\" missing after ACL \"%s\" %s", name,
861 cond_modifiers[c]? US"modifier" : US"condition");
862 return NULL;
863 }
864 while (isspace(*s)) s++;
865 cond->arg = string_copy(s);
866 }
867 }
868
869 return yield;
870 }
871
872
873
874 /*************************************************
875 * Set up added header line(s) *
876 *************************************************/
877
878 /* This function is called by the add_header modifier, and also from acl_warn()
879 to implement the now-deprecated way of adding header lines using "message" on a
880 "warn" verb. The argument is treated as a sequence of header lines which are
881 added to a chain, provided there isn't an identical one already there.
882
883 Argument: string of header lines
884 Returns: nothing
885 */
886
887 static void
888 setup_header(uschar *hstring)
889 {
890 uschar *p, *q;
891 int hlen = Ustrlen(hstring);
892
893 /* An empty string does nothing; otherwise add a final newline if necessary. */
894
895 if (hlen <= 0) return;
896 if (hstring[hlen-1] != '\n') hstring = string_sprintf("%s\n", hstring);
897
898 /* Loop for multiple header lines, taking care about continuations */
899
900 for (p = q = hstring; *p != 0; )
901 {
902 uschar *s;
903 int newtype = htype_add_bot;
904 header_line **hptr = &acl_added_headers;
905
906 /* Find next header line within the string */
907
908 for (;;)
909 {
910 q = Ustrchr(q, '\n');
911 if (*(++q) != ' ' && *q != '\t') break;
912 }
913
914 /* If the line starts with a colon, interpret the instruction for where to
915 add it. This temporarily sets up a new type. */
916
917 if (*p == ':')
918 {
919 if (strncmpic(p, US":after_received:", 16) == 0)
920 {
921 newtype = htype_add_rec;
922 p += 16;
923 }
924 else if (strncmpic(p, US":at_start_rfc:", 14) == 0)
925 {
926 newtype = htype_add_rfc;
927 p += 14;
928 }
929 else if (strncmpic(p, US":at_start:", 10) == 0)
930 {
931 newtype = htype_add_top;
932 p += 10;
933 }
934 else if (strncmpic(p, US":at_end:", 8) == 0)
935 {
936 newtype = htype_add_bot;
937 p += 8;
938 }
939 while (*p == ' ' || *p == '\t') p++;
940 }
941
942 /* See if this line starts with a header name, and if not, add X-ACL-Warn:
943 to the front of it. */
944
945 for (s = p; s < q - 1; s++)
946 {
947 if (*s == ':' || !isgraph(*s)) break;
948 }
949
950 s = string_sprintf("%s%.*s", (*s == ':')? "" : "X-ACL-Warn: ", q - p, p);
951 hlen = Ustrlen(s);
952
953 /* See if this line has already been added */
954
955 while (*hptr != NULL)
956 {
957 if (Ustrncmp((*hptr)->text, s, hlen) == 0) break;
958 hptr = &((*hptr)->next);
959 }
960
961 /* Add if not previously present */
962
963 if (*hptr == NULL)
964 {
965 header_line *h = store_get(sizeof(header_line));
966 h->text = s;
967 h->next = NULL;
968 h->type = newtype;
969 h->slen = hlen;
970 *hptr = h;
971 hptr = &(h->next);
972 }
973
974 /* Advance for next header line within the string */
975
976 p = q;
977 }
978 }
979
980
981
982
983 /*************************************************
984 * Handle warnings *
985 *************************************************/
986
987 /* This function is called when a WARN verb's conditions are true. It adds to
988 the message's headers, and/or writes information to the log. In each case, this
989 only happens once (per message for headers, per connection for log).
990
991 ** NOTE: The header adding action using the "message" setting is historic, and
992 its use is now deprecated. The new add_header modifier should be used instead.
993
994 Arguments:
995 where ACL_WHERE_xxxx indicating which ACL this is
996 user_message message for adding to headers
997 log_message message for logging, if different
998
999 Returns: nothing
1000 */
1001
1002 static void
1003 acl_warn(int where, uschar *user_message, uschar *log_message)
1004 {
1005 if (log_message != NULL && log_message != user_message)
1006 {
1007 uschar *text;
1008 string_item *logged;
1009
1010 text = string_sprintf("%s Warning: %s", host_and_ident(TRUE),
1011 string_printing(log_message));
1012
1013 /* If a sender verification has failed, and the log message is "sender verify
1014 failed", add the failure message. */
1015
1016 if (sender_verified_failed != NULL &&
1017 sender_verified_failed->message != NULL &&
1018 strcmpic(log_message, US"sender verify failed") == 0)
1019 text = string_sprintf("%s: %s", text, sender_verified_failed->message);
1020
1021 /* Search previously logged warnings. They are kept in malloc
1022 store so they can be freed at the start of a new message. */
1023
1024 for (logged = acl_warn_logged; logged != NULL; logged = logged->next)
1025 if (Ustrcmp(logged->text, text) == 0) break;
1026
1027 if (logged == NULL)
1028 {
1029 int length = Ustrlen(text) + 1;
1030 log_write(0, LOG_MAIN, "%s", text);
1031 logged = store_malloc(sizeof(string_item) + length);
1032 logged->text = (uschar *)logged + sizeof(string_item);
1033 memcpy(logged->text, text, length);
1034 logged->next = acl_warn_logged;
1035 acl_warn_logged = logged;
1036 }
1037 }
1038
1039 /* If there's no user message, we are done. */
1040
1041 if (user_message == NULL) return;
1042
1043 /* If this isn't a message ACL, we can't do anything with a user message.
1044 Log an error. */
1045
1046 if (where > ACL_WHERE_NOTSMTP)
1047 {
1048 log_write(0, LOG_MAIN|LOG_PANIC, "ACL \"warn\" with \"message\" setting "
1049 "found in a non-message (%s) ACL: cannot specify header lines here: "
1050 "message ignored", acl_wherenames[where]);
1051 return;
1052 }
1053
1054 /* The code for setting up header lines is now abstracted into a separate
1055 function so that it can be used for the add_header modifier as well. */
1056
1057 setup_header(user_message);
1058 }
1059
1060
1061
1062 /*************************************************
1063 * Verify and check reverse DNS *
1064 *************************************************/
1065
1066 /* Called from acl_verify() below. We look up the host name(s) of the client IP
1067 address if this has not yet been done. The host_name_lookup() function checks
1068 that one of these names resolves to an address list that contains the client IP
1069 address, so we don't actually have to do the check here.
1070
1071 Arguments:
1072 user_msgptr pointer for user message
1073 log_msgptr pointer for log message
1074
1075 Returns: OK verification condition succeeded
1076 FAIL verification failed
1077 DEFER there was a problem verifying
1078 */
1079
1080 static int
1081 acl_verify_reverse(uschar **user_msgptr, uschar **log_msgptr)
1082 {
1083 int rc;
1084
1085 user_msgptr = user_msgptr; /* stop compiler warning */
1086
1087 /* Previous success */
1088
1089 if (sender_host_name != NULL) return OK;
1090
1091 /* Previous failure */
1092
1093 if (host_lookup_failed)
1094 {
1095 *log_msgptr = string_sprintf("host lookup failed%s", host_lookup_msg);
1096 return FAIL;
1097 }
1098
1099 /* Need to do a lookup */
1100
1101 HDEBUG(D_acl)
1102 debug_printf("looking up host name to force name/address consistency check\n");
1103
1104 if ((rc = host_name_lookup()) != OK)
1105 {
1106 *log_msgptr = (rc == DEFER)?
1107 US"host lookup deferred for reverse lookup check"
1108 :
1109 string_sprintf("host lookup failed for reverse lookup check%s",
1110 host_lookup_msg);
1111 return rc; /* DEFER or FAIL */
1112 }
1113
1114 host_build_sender_fullhost();
1115 return OK;
1116 }
1117
1118
1119
1120 /*************************************************
1121 * Check client IP address matches CSA target *
1122 *************************************************/
1123
1124 /* Called from acl_verify_csa() below. This routine scans a section of a DNS
1125 response for address records belonging to the CSA target hostname. The section
1126 is specified by the reset argument, either RESET_ADDITIONAL or RESET_ANSWERS.
1127 If one of the addresses matches the client's IP address, then the client is
1128 authorized by CSA. If there are target IP addresses but none of them match
1129 then the client is using an unauthorized IP address. If there are no target IP
1130 addresses then the client cannot be using an authorized IP address. (This is
1131 an odd configuration - why didn't the SRV record have a weight of 1 instead?)
1132
1133 Arguments:
1134 dnsa the DNS answer block
1135 dnss a DNS scan block for us to use
1136 reset option specifing what portion to scan, as described above
1137 target the target hostname to use for matching RR names
1138
1139 Returns: CSA_OK successfully authorized
1140 CSA_FAIL_MISMATCH addresses found but none matched
1141 CSA_FAIL_NOADDR no target addresses found
1142 */
1143
1144 static int
1145 acl_verify_csa_address(dns_answer *dnsa, dns_scan *dnss, int reset,
1146 uschar *target)
1147 {
1148 dns_record *rr;
1149 dns_address *da;
1150
1151 BOOL target_found = FALSE;
1152
1153 for (rr = dns_next_rr(dnsa, dnss, reset);
1154 rr != NULL;
1155 rr = dns_next_rr(dnsa, dnss, RESET_NEXT))
1156 {
1157 /* Check this is an address RR for the target hostname. */
1158
1159 if (rr->type != T_A
1160 #if HAVE_IPV6
1161 && rr->type != T_AAAA
1162 #ifdef SUPPORT_A6
1163 && rr->type != T_A6
1164 #endif
1165 #endif
1166 ) continue;
1167
1168 if (strcmpic(target, rr->name) != 0) continue;
1169
1170 target_found = TRUE;
1171
1172 /* Turn the target address RR into a list of textual IP addresses and scan
1173 the list. There may be more than one if it is an A6 RR. */
1174
1175 for (da = dns_address_from_rr(dnsa, rr); da != NULL; da = da->next)
1176 {
1177 /* If the client IP address matches the target IP address, it's good! */
1178
1179 DEBUG(D_acl) debug_printf("CSA target address is %s\n", da->address);
1180
1181 if (strcmpic(sender_host_address, da->address) == 0) return CSA_OK;
1182 }
1183 }
1184
1185 /* If we found some target addresses but none of them matched, the client is
1186 using an unauthorized IP address, otherwise the target has no authorized IP
1187 addresses. */
1188
1189 if (target_found) return CSA_FAIL_MISMATCH;
1190 else return CSA_FAIL_NOADDR;
1191 }
1192
1193
1194
1195 /*************************************************
1196 * Verify Client SMTP Authorization *
1197 *************************************************/
1198
1199 /* Called from acl_verify() below. This routine calls dns_lookup_special()
1200 to find the CSA SRV record corresponding to the domain argument, or
1201 $sender_helo_name if no argument is provided. It then checks that the
1202 client is authorized, and that its IP address corresponds to the SRV
1203 target's address by calling acl_verify_csa_address() above. The address
1204 should have been returned in the DNS response's ADDITIONAL section, but if
1205 not we perform another DNS lookup to get it.
1206
1207 Arguments:
1208 domain pointer to optional parameter following verify = csa
1209
1210 Returns: CSA_UNKNOWN no valid CSA record found
1211 CSA_OK successfully authorized
1212 CSA_FAIL_* client is definitely not authorized
1213 CSA_DEFER_* there was a DNS problem
1214 */
1215
1216 static int
1217 acl_verify_csa(uschar *domain)
1218 {
1219 tree_node *t;
1220 uschar *found, *p;
1221 int priority, weight, port;
1222 dns_answer dnsa;
1223 dns_scan dnss;
1224 dns_record *rr;
1225 int rc, type;
1226 uschar target[256];
1227
1228 /* Work out the domain we are using for the CSA lookup. The default is the
1229 client's HELO domain. If the client has not said HELO, use its IP address
1230 instead. If it's a local client (exim -bs), CSA isn't applicable. */
1231
1232 while (isspace(*domain) && *domain != '\0') ++domain;
1233 if (*domain == '\0') domain = sender_helo_name;
1234 if (domain == NULL) domain = sender_host_address;
1235 if (sender_host_address == NULL) return CSA_UNKNOWN;
1236
1237 /* If we have an address literal, strip off the framing ready for turning it
1238 into a domain. The framing consists of matched square brackets possibly
1239 containing a keyword and a colon before the actual IP address. */
1240
1241 if (domain[0] == '[')
1242 {
1243 uschar *start = Ustrchr(domain, ':');
1244 if (start == NULL) start = domain;
1245 domain = string_copyn(start + 1, Ustrlen(start) - 2);
1246 }
1247
1248 /* Turn domains that look like bare IP addresses into domains in the reverse
1249 DNS. This code also deals with address literals and $sender_host_address. It's
1250 not quite kosher to treat bare domains such as EHLO 192.0.2.57 the same as
1251 address literals, but it's probably the most friendly thing to do. This is an
1252 extension to CSA, so we allow it to be turned off for proper conformance. */
1253
1254 if (string_is_ip_address(domain, NULL) != 0)
1255 {
1256 if (!dns_csa_use_reverse) return CSA_UNKNOWN;
1257 dns_build_reverse(domain, target);
1258 domain = target;
1259 }
1260
1261 /* Find out if we've already done the CSA check for this domain. If we have,
1262 return the same result again. Otherwise build a new cached result structure
1263 for this domain. The name is filled in now, and the value is filled in when
1264 we return from this function. */
1265
1266 t = tree_search(csa_cache, domain);
1267 if (t != NULL) return t->data.val;
1268
1269 t = store_get_perm(sizeof(tree_node) + Ustrlen(domain));
1270 Ustrcpy(t->name, domain);
1271 (void)tree_insertnode(&csa_cache, t);
1272
1273 /* Now we are ready to do the actual DNS lookup(s). */
1274
1275 found = domain;
1276 switch (dns_special_lookup(&dnsa, domain, T_CSA, &found))
1277 {
1278 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1279
1280 default:
1281 return t->data.val = CSA_DEFER_SRV;
1282
1283 /* If we found nothing, the client's authorization is unknown. */
1284
1285 case DNS_NOMATCH:
1286 case DNS_NODATA:
1287 return t->data.val = CSA_UNKNOWN;
1288
1289 /* We got something! Go on to look at the reply in more detail. */
1290
1291 case DNS_SUCCEED:
1292 break;
1293 }
1294
1295 /* Scan the reply for well-formed CSA SRV records. */
1296
1297 for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS);
1298 rr != NULL;
1299 rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT))
1300 {
1301 if (rr->type != T_SRV) continue;
1302
1303 /* Extract the numerical SRV fields (p is incremented) */
1304
1305 p = rr->data;
1306 GETSHORT(priority, p);
1307 GETSHORT(weight, p);
1308 GETSHORT(port, p);
1309
1310 DEBUG(D_acl)
1311 debug_printf("CSA priority=%d weight=%d port=%d\n", priority, weight, port);
1312
1313 /* Check the CSA version number */
1314
1315 if (priority != 1) continue;
1316
1317 /* If the domain does not have a CSA SRV record of its own (i.e. the domain
1318 found by dns_special_lookup() is a parent of the one we asked for), we check
1319 the subdomain assertions in the port field. At the moment there's only one
1320 assertion: legitimate SMTP clients are all explicitly authorized with CSA
1321 SRV records of their own. */
1322
1323 if (found != domain)
1324 {
1325 if (port & 1)
1326 return t->data.val = CSA_FAIL_EXPLICIT;
1327 else
1328 return t->data.val = CSA_UNKNOWN;
1329 }
1330
1331 /* This CSA SRV record refers directly to our domain, so we check the value
1332 in the weight field to work out the domain's authorization. 0 and 1 are
1333 unauthorized; 3 means the client is authorized but we can't check the IP
1334 address in order to authenticate it, so we treat it as unknown; values
1335 greater than 3 are undefined. */
1336
1337 if (weight < 2) return t->data.val = CSA_FAIL_DOMAIN;
1338
1339 if (weight > 2) continue;
1340
1341 /* Weight == 2, which means the domain is authorized. We must check that the
1342 client's IP address is listed as one of the SRV target addresses. Save the
1343 target hostname then break to scan the additional data for its addresses. */
1344
1345 (void)dn_expand(dnsa.answer, dnsa.answer + dnsa.answerlen, p,
1346 (DN_EXPAND_ARG4_TYPE)target, sizeof(target));
1347
1348 DEBUG(D_acl) debug_printf("CSA target is %s\n", target);
1349
1350 break;
1351 }
1352
1353 /* If we didn't break the loop then no appropriate records were found. */
1354
1355 if (rr == NULL) return t->data.val = CSA_UNKNOWN;
1356
1357 /* Do not check addresses if the target is ".", in accordance with RFC 2782.
1358 A target of "." indicates there are no valid addresses, so the client cannot
1359 be authorized. (This is an odd configuration because weight=2 target=. is
1360 equivalent to weight=1, but we check for it in order to keep load off the
1361 root name servers.) Note that dn_expand() turns "." into "". */
1362
1363 if (Ustrcmp(target, "") == 0) return t->data.val = CSA_FAIL_NOADDR;
1364
1365 /* Scan the additional section of the CSA SRV reply for addresses belonging
1366 to the target. If the name server didn't return any additional data (e.g.
1367 because it does not fully support SRV records), we need to do another lookup
1368 to obtain the target addresses; otherwise we have a definitive result. */
1369
1370 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ADDITIONAL, target);
1371 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1372
1373 /* The DNS lookup type corresponds to the IP version used by the client. */
1374
1375 #if HAVE_IPV6
1376 if (Ustrchr(sender_host_address, ':') != NULL)
1377 type = T_AAAA;
1378 else
1379 #endif /* HAVE_IPV6 */
1380 type = T_A;
1381
1382
1383 #if HAVE_IPV6 && defined(SUPPORT_A6)
1384 DNS_LOOKUP_AGAIN:
1385 #endif
1386
1387 switch (dns_lookup(&dnsa, target, type, NULL))
1388 {
1389 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1390
1391 default:
1392 return t->data.val = CSA_DEFER_ADDR;
1393
1394 /* If the query succeeded, scan the addresses and return the result. */
1395
1396 case DNS_SUCCEED:
1397 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ANSWERS, target);
1398 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1399 /* else fall through */
1400
1401 /* If the target has no IP addresses, the client cannot have an authorized
1402 IP address. However, if the target site uses A6 records (not AAAA records)
1403 we have to do yet another lookup in order to check them. */
1404
1405 case DNS_NOMATCH:
1406 case DNS_NODATA:
1407
1408 #if HAVE_IPV6 && defined(SUPPORT_A6)
1409 if (type == T_AAAA) { type = T_A6; goto DNS_LOOKUP_AGAIN; }
1410 #endif
1411
1412 return t->data.val = CSA_FAIL_NOADDR;
1413 }
1414 }
1415
1416
1417
1418 /*************************************************
1419 * Handle verification (address & other) *
1420 *************************************************/
1421
1422 /* This function implements the "verify" condition. It is called when
1423 encountered in any ACL, because some tests are almost always permitted. Some
1424 just don't make sense, and always fail (for example, an attempt to test a host
1425 lookup for a non-TCP/IP message). Others are restricted to certain ACLs.
1426
1427 Arguments:
1428 where where called from
1429 addr the recipient address that the ACL is handling, or NULL
1430 arg the argument of "verify"
1431 user_msgptr pointer for user message
1432 log_msgptr pointer for log message
1433 basic_errno where to put verify errno
1434
1435 Returns: OK verification condition succeeded
1436 FAIL verification failed
1437 DEFER there was a problem verifying
1438 ERROR syntax error
1439 */
1440
1441 static int
1442 acl_verify(int where, address_item *addr, uschar *arg,
1443 uschar **user_msgptr, uschar **log_msgptr, int *basic_errno)
1444 {
1445 int sep = '/';
1446 int callout = -1;
1447 int callout_overall = -1;
1448 int callout_connect = -1;
1449 int verify_options = 0;
1450 int rc;
1451 BOOL verify_header_sender = FALSE;
1452 BOOL defer_ok = FALSE;
1453 BOOL callout_defer_ok = FALSE;
1454 BOOL no_details = FALSE;
1455 BOOL success_on_redirect = FALSE;
1456 address_item *sender_vaddr = NULL;
1457 uschar *verify_sender_address = NULL;
1458 uschar *pm_mailfrom = NULL;
1459 uschar *se_mailfrom = NULL;
1460
1461 /* Some of the verify items have slash-separated options; some do not. Diagnose
1462 an error if options are given for items that don't expect them. This code has
1463 now got very message. Refactoring to use a table would be a good idea one day.
1464 */
1465
1466 uschar *slash = Ustrchr(arg, '/');
1467 uschar *list = arg;
1468 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
1469
1470 if (ss == NULL) goto BAD_VERIFY;
1471
1472 /* Handle name/address consistency verification in a separate function. */
1473
1474 if (strcmpic(ss, US"reverse_host_lookup") == 0)
1475 {
1476 if (slash != NULL) goto NO_OPTIONS;
1477 if (sender_host_address == NULL) return OK;
1478 return acl_verify_reverse(user_msgptr, log_msgptr);
1479 }
1480
1481 /* TLS certificate verification is done at STARTTLS time; here we just
1482 test whether it was successful or not. (This is for optional verification; for
1483 mandatory verification, the connection doesn't last this long.) */
1484
1485 if (strcmpic(ss, US"certificate") == 0)
1486 {
1487 if (slash != NULL) goto NO_OPTIONS;
1488 if (tls_certificate_verified) return OK;
1489 *user_msgptr = US"no verified certificate";
1490 return FAIL;
1491 }
1492
1493 /* We can test the result of optional HELO verification that might have
1494 occurred earlier. If not, we can attempt the verification now. */
1495
1496 if (strcmpic(ss, US"helo") == 0)
1497 {
1498 if (slash != NULL) goto NO_OPTIONS;
1499 if (!helo_verified && !helo_verify_failed) smtp_verify_helo();
1500 return helo_verified? OK : FAIL;
1501 }
1502
1503 /* Do Client SMTP Authorization checks in a separate function, and turn the
1504 result code into user-friendly strings. */
1505
1506 if (strcmpic(ss, US"csa") == 0)
1507 {
1508 rc = acl_verify_csa(list);
1509 *log_msgptr = *user_msgptr = string_sprintf("client SMTP authorization %s",
1510 csa_reason_string[rc]);
1511 csa_status = csa_status_string[rc];
1512 DEBUG(D_acl) debug_printf("CSA result %s\n", csa_status);
1513 return csa_return_code[rc];
1514 }
1515
1516 /* Check that all relevant header lines have the correct syntax. If there is
1517 a syntax error, we return details of the error to the sender if configured to
1518 send out full details. (But a "message" setting on the ACL can override, as
1519 always). */
1520
1521 if (strcmpic(ss, US"header_syntax") == 0)
1522 {
1523 if (slash != NULL) goto NO_OPTIONS;
1524 if (where != ACL_WHERE_DATA && where != ACL_WHERE_NOTSMTP) goto WRONG_ACL;
1525 rc = verify_check_headers(log_msgptr);
1526 if (rc != OK && smtp_return_error_details && *log_msgptr != NULL)
1527 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1528 return rc;
1529 }
1530
1531 /* Check that no recipient of this message is "blind", that is, every envelope
1532 recipient must be mentioned in either To: or Cc:. */
1533
1534 if (strcmpic(ss, US"not_blind") == 0)
1535 {
1536 if (slash != NULL) goto NO_OPTIONS;
1537 if (where != ACL_WHERE_DATA && where != ACL_WHERE_NOTSMTP) goto WRONG_ACL;
1538 rc = verify_check_notblind();
1539 if (rc != OK)
1540 {
1541 *log_msgptr = string_sprintf("bcc recipient detected");
1542 if (smtp_return_error_details)
1543 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1544 }
1545 return rc;
1546 }
1547
1548 /* The remaining verification tests check recipient and sender addresses,
1549 either from the envelope or from the header. There are a number of
1550 slash-separated options that are common to all of them. */
1551
1552
1553 /* Check that there is at least one verifiable sender address in the relevant
1554 header lines. This can be followed by callout and defer options, just like
1555 sender and recipient. */
1556
1557 if (strcmpic(ss, US"header_sender") == 0)
1558 {
1559 if (where != ACL_WHERE_DATA && where != ACL_WHERE_NOTSMTP) goto WRONG_ACL;
1560 verify_header_sender = TRUE;
1561 }
1562
1563 /* Otherwise, first item in verify argument must be "sender" or "recipient".
1564 In the case of a sender, this can optionally be followed by an address to use
1565 in place of the actual sender (rare special-case requirement). */
1566
1567 else if (strncmpic(ss, US"sender", 6) == 0)
1568 {
1569 uschar *s = ss + 6;
1570 if (where > ACL_WHERE_NOTSMTP)
1571 {
1572 *log_msgptr = string_sprintf("cannot verify sender in ACL for %s "
1573 "(only possible for MAIL, RCPT, PREDATA, or DATA)",
1574 acl_wherenames[where]);
1575 return ERROR;
1576 }
1577 if (*s == 0)
1578 verify_sender_address = sender_address;
1579 else
1580 {
1581 while (isspace(*s)) s++;
1582 if (*s++ != '=') goto BAD_VERIFY;
1583 while (isspace(*s)) s++;
1584 verify_sender_address = string_copy(s);
1585 }
1586 }
1587 else
1588 {
1589 if (strcmpic(ss, US"recipient") != 0) goto BAD_VERIFY;
1590 if (addr == NULL)
1591 {
1592 *log_msgptr = string_sprintf("cannot verify recipient in ACL for %s "
1593 "(only possible for RCPT)", acl_wherenames[where]);
1594 return ERROR;
1595 }
1596 }
1597
1598 /* Remaining items are optional; they apply to sender and recipient
1599 verification, including "header sender" verification. */
1600
1601 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size))
1602 != NULL)
1603 {
1604 if (strcmpic(ss, US"defer_ok") == 0) defer_ok = TRUE;
1605 else if (strcmpic(ss, US"no_details") == 0) no_details = TRUE;
1606 else if (strcmpic(ss, US"success_on_redirect") == 0) success_on_redirect = TRUE;
1607
1608 /* These two old options are left for backwards compatibility */
1609
1610 else if (strcmpic(ss, US"callout_defer_ok") == 0)
1611 {
1612 callout_defer_ok = TRUE;
1613 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1614 }
1615
1616 else if (strcmpic(ss, US"check_postmaster") == 0)
1617 {
1618 pm_mailfrom = US"";
1619 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1620 }
1621
1622 /* The callout option has a number of sub-options, comma separated */
1623
1624 else if (strncmpic(ss, US"callout", 7) == 0)
1625 {
1626 callout = CALLOUT_TIMEOUT_DEFAULT;
1627 ss += 7;
1628 if (*ss != 0)
1629 {
1630 while (isspace(*ss)) ss++;
1631 if (*ss++ == '=')
1632 {
1633 int optsep = ',';
1634 uschar *opt;
1635 uschar buffer[256];
1636 while (isspace(*ss)) ss++;
1637
1638 /* This callout option handling code has become a mess as new options
1639 have been added in an ad hoc manner. It should be tidied up into some
1640 kind of table-driven thing. */
1641
1642 while ((opt = string_nextinlist(&ss, &optsep, buffer, sizeof(buffer)))
1643 != NULL)
1644 {
1645 if (strcmpic(opt, US"defer_ok") == 0) callout_defer_ok = TRUE;
1646 else if (strcmpic(opt, US"no_cache") == 0)
1647 verify_options |= vopt_callout_no_cache;
1648 else if (strcmpic(opt, US"random") == 0)
1649 verify_options |= vopt_callout_random;
1650 else if (strcmpic(opt, US"use_sender") == 0)
1651 verify_options |= vopt_callout_recipsender;
1652 else if (strcmpic(opt, US"use_postmaster") == 0)
1653 verify_options |= vopt_callout_recippmaster;
1654 else if (strcmpic(opt, US"postmaster") == 0) pm_mailfrom = US"";
1655 else if (strcmpic(opt, US"fullpostmaster") == 0)
1656 {
1657 pm_mailfrom = US"";
1658 verify_options |= vopt_callout_fullpm;
1659 }
1660
1661 else if (strncmpic(opt, US"mailfrom", 8) == 0)
1662 {
1663 if (!verify_header_sender)
1664 {
1665 *log_msgptr = string_sprintf("\"mailfrom\" is allowed as a "
1666 "callout option only for verify=header_sender (detected in ACL "
1667 "condition \"%s\")", arg);
1668 return ERROR;
1669 }
1670 opt += 8;
1671 while (isspace(*opt)) opt++;
1672 if (*opt++ != '=')
1673 {
1674 *log_msgptr = string_sprintf("'=' expected after "
1675 "\"mailfrom\" in ACL condition \"%s\"", arg);
1676 return ERROR;
1677 }
1678 while (isspace(*opt)) opt++;
1679 se_mailfrom = string_copy(opt);
1680 }
1681
1682 else if (strncmpic(opt, US"postmaster_mailfrom", 19) == 0)
1683 {
1684 opt += 19;
1685 while (isspace(*opt)) opt++;
1686 if (*opt++ != '=')
1687 {
1688 *log_msgptr = string_sprintf("'=' expected after "
1689 "\"postmaster_mailfrom\" in ACL condition \"%s\"", arg);
1690 return ERROR;
1691 }
1692 while (isspace(*opt)) opt++;
1693 pm_mailfrom = string_copy(opt);
1694 }
1695
1696 else if (strncmpic(opt, US"maxwait", 7) == 0)
1697 {
1698 opt += 7;
1699 while (isspace(*opt)) opt++;
1700 if (*opt++ != '=')
1701 {
1702 *log_msgptr = string_sprintf("'=' expected after \"maxwait\" in "
1703 "ACL condition \"%s\"", arg);
1704 return ERROR;
1705 }
1706 while (isspace(*opt)) opt++;
1707 callout_overall = readconf_readtime(opt, 0, FALSE);
1708 if (callout_overall < 0)
1709 {
1710 *log_msgptr = string_sprintf("bad time value in ACL condition "
1711 "\"verify %s\"", arg);
1712 return ERROR;
1713 }
1714 }
1715 else if (strncmpic(opt, US"connect", 7) == 0)
1716 {
1717 opt += 7;
1718 while (isspace(*opt)) opt++;
1719 if (*opt++ != '=')
1720 {
1721 *log_msgptr = string_sprintf("'=' expected after "
1722 "\"callout_overaall\" in ACL condition \"%s\"", arg);
1723 return ERROR;
1724 }
1725 while (isspace(*opt)) opt++;
1726 callout_connect = readconf_readtime(opt, 0, FALSE);
1727 if (callout_connect < 0)
1728 {
1729 *log_msgptr = string_sprintf("bad time value in ACL condition "
1730 "\"verify %s\"", arg);
1731 return ERROR;
1732 }
1733 }
1734 else /* Plain time is callout connect/command timeout */
1735 {
1736 callout = readconf_readtime(opt, 0, FALSE);
1737 if (callout < 0)
1738 {
1739 *log_msgptr = string_sprintf("bad time value in ACL condition "
1740 "\"verify %s\"", arg);
1741 return ERROR;
1742 }
1743 }
1744 }
1745 }
1746 else
1747 {
1748 *log_msgptr = string_sprintf("'=' expected after \"callout\" in "
1749 "ACL condition \"%s\"", arg);
1750 return ERROR;
1751 }
1752 }
1753 }
1754
1755 /* Option not recognized */
1756
1757 else
1758 {
1759 *log_msgptr = string_sprintf("unknown option \"%s\" in ACL "
1760 "condition \"verify %s\"", ss, arg);
1761 return ERROR;
1762 }
1763 }
1764
1765 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster)) ==
1766 (vopt_callout_recipsender|vopt_callout_recippmaster))
1767 {
1768 *log_msgptr = US"only one of use_sender and use_postmaster can be set "
1769 "for a recipient callout";
1770 return ERROR;
1771 }
1772
1773 /* Handle sender-in-header verification. Default the user message to the log
1774 message if giving out verification details. */
1775
1776 if (verify_header_sender)
1777 {
1778 int verrno;
1779 rc = verify_check_header_address(user_msgptr, log_msgptr, callout,
1780 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, verify_options,
1781 &verrno);
1782 if (rc != OK)
1783 {
1784 *basic_errno = verrno;
1785 if (smtp_return_error_details)
1786 {
1787 if (*user_msgptr == NULL && *log_msgptr != NULL)
1788 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1789 if (rc == DEFER) acl_temp_details = TRUE;
1790 }
1791 }
1792 }
1793
1794 /* Handle a sender address. The default is to verify *the* sender address, but
1795 optionally a different address can be given, for special requirements. If the
1796 address is empty, we are dealing with a bounce message that has no sender, so
1797 we cannot do any checking. If the real sender address gets rewritten during
1798 verification (e.g. DNS widening), set the flag to stop it being rewritten again
1799 during message reception.
1800
1801 A list of verified "sender" addresses is kept to try to avoid doing to much
1802 work repetitively when there are multiple recipients in a message and they all
1803 require sender verification. However, when callouts are involved, it gets too
1804 complicated because different recipients may require different callout options.
1805 Therefore, we always do a full sender verify when any kind of callout is
1806 specified. Caching elsewhere, for instance in the DNS resolver and in the
1807 callout handling, should ensure that this is not terribly inefficient. */
1808
1809 else if (verify_sender_address != NULL)
1810 {
1811 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster))
1812 != 0)
1813 {
1814 *log_msgptr = US"use_sender or use_postmaster cannot be used for a "
1815 "sender verify callout";
1816 return ERROR;
1817 }
1818
1819 sender_vaddr = verify_checked_sender(verify_sender_address);
1820 if (sender_vaddr != NULL && /* Previously checked */
1821 callout <= 0) /* No callout needed this time */
1822 {
1823 /* If the "routed" flag is set, it means that routing worked before, so
1824 this check can give OK (the saved return code value, if set, belongs to a
1825 callout that was done previously). If the "routed" flag is not set, routing
1826 must have failed, so we use the saved return code. */
1827
1828 if (testflag(sender_vaddr, af_verify_routed)) rc = OK; else
1829 {
1830 rc = sender_vaddr->special_action;
1831 *basic_errno = sender_vaddr->basic_errno;
1832 }
1833 HDEBUG(D_acl) debug_printf("using cached sender verify result\n");
1834 }
1835
1836 /* Do a new verification, and cache the result. The cache is used to avoid
1837 verifying the sender multiple times for multiple RCPTs when callouts are not
1838 specified (see comments above).
1839
1840 The cache is also used on failure to give details in response to the first
1841 RCPT that gets bounced for this reason. However, this can be suppressed by
1842 the no_details option, which sets the flag that says "this detail has already
1843 been sent". The cache normally contains just one address, but there may be
1844 more in esoteric circumstances. */
1845
1846 else
1847 {
1848 BOOL routed = TRUE;
1849 uschar *save_address_data = deliver_address_data;
1850
1851 sender_vaddr = deliver_make_addr(verify_sender_address, TRUE);
1852 if (no_details) setflag(sender_vaddr, af_sverify_told);
1853 if (verify_sender_address[0] != 0)
1854 {
1855 /* If this is the real sender address, save the unrewritten version
1856 for use later in receive. Otherwise, set a flag so that rewriting the
1857 sender in verify_address() does not update sender_address. */
1858
1859 if (verify_sender_address == sender_address)
1860 sender_address_unrewritten = sender_address;
1861 else
1862 verify_options |= vopt_fake_sender;
1863
1864 if (success_on_redirect)
1865 verify_options |= vopt_success_on_redirect;
1866
1867 /* The recipient, qualify, and expn options are never set in
1868 verify_options. */
1869
1870 rc = verify_address(sender_vaddr, NULL, verify_options, callout,
1871 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, &routed);
1872
1873 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
1874
1875 if (rc == OK)
1876 {
1877 if (Ustrcmp(sender_vaddr->address, verify_sender_address) != 0)
1878 {
1879 DEBUG(D_acl) debug_printf("sender %s verified ok as %s\n",
1880 verify_sender_address, sender_vaddr->address);
1881 }
1882 else
1883 {
1884 DEBUG(D_acl) debug_printf("sender %s verified ok\n",
1885 verify_sender_address);
1886 }
1887 }
1888 else *basic_errno = sender_vaddr->basic_errno;
1889 }
1890 else rc = OK; /* Null sender */
1891
1892 /* Cache the result code */
1893
1894 if (routed) setflag(sender_vaddr, af_verify_routed);
1895 if (callout > 0) setflag(sender_vaddr, af_verify_callout);
1896 sender_vaddr->special_action = rc;
1897 sender_vaddr->next = sender_verified_list;
1898 sender_verified_list = sender_vaddr;
1899
1900 /* Restore the recipient address data, which might have been clobbered by
1901 the sender verification. */
1902
1903 deliver_address_data = save_address_data;
1904 }
1905
1906 /* Put the sender address_data value into $sender_address_data */
1907
1908 sender_address_data = sender_vaddr->p.address_data;
1909 }
1910
1911 /* A recipient address just gets a straightforward verify; again we must handle
1912 the DEFER overrides. */
1913
1914 else
1915 {
1916 address_item addr2;
1917
1918 if (success_on_redirect)
1919 verify_options |= vopt_success_on_redirect;
1920
1921 /* We must use a copy of the address for verification, because it might
1922 get rewritten. */
1923
1924 addr2 = *addr;
1925 rc = verify_address(&addr2, NULL, verify_options|vopt_is_recipient, callout,
1926 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, NULL);
1927 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
1928
1929 *log_msgptr = addr2.message;
1930 *user_msgptr = (addr2.user_message != NULL)?
1931 addr2.user_message : addr2.message;
1932 *basic_errno = addr2.basic_errno;
1933
1934 /* Make $address_data visible */
1935 deliver_address_data = addr2.p.address_data;
1936 }
1937
1938 /* We have a result from the relevant test. Handle defer overrides first. */
1939
1940 if (rc == DEFER && (defer_ok ||
1941 (callout_defer_ok && *basic_errno == ERRNO_CALLOUTDEFER)))
1942 {
1943 HDEBUG(D_acl) debug_printf("verify defer overridden by %s\n",
1944 defer_ok? "defer_ok" : "callout_defer_ok");
1945 rc = OK;
1946 }
1947
1948 /* If we've failed a sender, set up a recipient message, and point
1949 sender_verified_failed to the address item that actually failed. */
1950
1951 if (rc != OK && verify_sender_address != NULL)
1952 {
1953 if (rc != DEFER)
1954 {
1955 *log_msgptr = *user_msgptr = US"Sender verify failed";
1956 }
1957 else if (*basic_errno != ERRNO_CALLOUTDEFER)
1958 {
1959 *log_msgptr = *user_msgptr = US"Could not complete sender verify";
1960 }
1961 else
1962 {
1963 *log_msgptr = US"Could not complete sender verify callout";
1964 *user_msgptr = smtp_return_error_details? sender_vaddr->user_message :
1965 *log_msgptr;
1966 }
1967
1968 sender_verified_failed = sender_vaddr;
1969 }
1970
1971 /* Verifying an address messes up the values of $domain and $local_part,
1972 so reset them before returning if this is a RCPT ACL. */
1973
1974 if (addr != NULL)
1975 {
1976 deliver_domain = addr->domain;
1977 deliver_localpart = addr->local_part;
1978 }
1979 return rc;
1980
1981 /* Syntax errors in the verify argument come here. */
1982
1983 BAD_VERIFY:
1984 *log_msgptr = string_sprintf("expected \"sender[=address]\", \"recipient\", "
1985 "\"helo\", \"header_syntax\", \"header_sender\" or "
1986 "\"reverse_host_lookup\" at start of ACL condition "
1987 "\"verify %s\"", arg);
1988 return ERROR;
1989
1990 /* Options supplied when not allowed come here */
1991
1992 NO_OPTIONS:
1993 *log_msgptr = string_sprintf("unexpected '/' found in \"%s\" "
1994 "(this verify item has no options)", arg);
1995 return ERROR;
1996
1997 /* Calls in the wrong ACL come here */
1998
1999 WRONG_ACL:
2000 *log_msgptr = string_sprintf("cannot check header contents in ACL for %s "
2001 "(only possible in ACL for DATA)", acl_wherenames[where]);
2002 return ERROR;
2003 }
2004
2005
2006
2007
2008 /*************************************************
2009 * Check argument for control= modifier *
2010 *************************************************/
2011
2012 /* Called from acl_check_condition() below
2013
2014 Arguments:
2015 arg the argument string for control=
2016 pptr set to point to the terminating character
2017 where which ACL we are in
2018 log_msgptr for error messages
2019
2020 Returns: CONTROL_xxx value
2021 */
2022
2023 static int
2024 decode_control(uschar *arg, uschar **pptr, int where, uschar **log_msgptr)
2025 {
2026 int len;
2027 control_def *d;
2028
2029 for (d = controls_list;
2030 d < controls_list + sizeof(controls_list)/sizeof(control_def);
2031 d++)
2032 {
2033 len = Ustrlen(d->name);
2034 if (Ustrncmp(d->name, arg, len) == 0) break;
2035 }
2036
2037 if (d >= controls_list + sizeof(controls_list)/sizeof(control_def) ||
2038 (arg[len] != 0 && (!d->has_option || arg[len] != '/')))
2039 {
2040 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
2041 return CONTROL_ERROR;
2042 }
2043
2044 *pptr = arg + len;
2045 return d->value;
2046 }
2047
2048
2049
2050 /*************************************************
2051 * Handle rate limiting *
2052 *************************************************/
2053
2054 /* Called by acl_check_condition() below to calculate the result
2055 of the ACL ratelimit condition.
2056
2057 Note that the return value might be slightly unexpected: if the
2058 sender's rate is above the limit then the result is OK. This is
2059 similar to the dnslists condition, and is so that you can write
2060 ACL clauses like: defer ratelimit = 15 / 1h
2061
2062 Arguments:
2063 arg the option string for ratelimit=
2064 where ACL_WHERE_xxxx indicating which ACL this is
2065 log_msgptr for error messages
2066
2067 Returns: OK - Sender's rate is above limit
2068 FAIL - Sender's rate is below limit
2069 DEFER - Problem opening ratelimit database
2070 ERROR - Syntax error in options.
2071 */
2072
2073 static int
2074 acl_ratelimit(uschar *arg, int where, uschar **log_msgptr)
2075 {
2076 double limit, period;
2077 uschar *ss, *key;
2078 int sep = '/';
2079 BOOL have_key = FALSE, leaky = FALSE, strict = FALSE;
2080 BOOL per_byte = FALSE, per_cmd = FALSE, per_conn = FALSE, per_mail = FALSE;
2081 int old_pool, rc;
2082 tree_node **anchor, *t;
2083 open_db dbblock, *dbm;
2084 dbdata_ratelimit *dbd;
2085 struct timeval tv;
2086
2087 /* Parse the first two options and record their values in expansion
2088 variables. These variables allow the configuration to have informative
2089 error messages based on rate limits obtained from a table lookup. */
2090
2091 /* First is the maximum number of messages per period and maximum burst
2092 size, which must be greater than or equal to zero. Zero is useful for
2093 rate measurement as opposed to rate limiting. */
2094
2095 sender_rate_limit = string_nextinlist(&arg, &sep, NULL, 0);
2096 if (sender_rate_limit == NULL)
2097 limit = -1.0;
2098 else
2099 {
2100 limit = Ustrtod(sender_rate_limit, &ss);
2101 if (tolower(*ss) == 'k') { limit *= 1024.0; ss++; }
2102 else if (tolower(*ss) == 'm') { limit *= 1024.0*1024.0; ss++; }
2103 else if (tolower(*ss) == 'g') { limit *= 1024.0*1024.0*1024.0; ss++; }
2104 }
2105 if (limit < 0.0 || *ss != 0)
2106 {
2107 *log_msgptr = string_sprintf("syntax error in argument for "
2108 "\"ratelimit\" condition: \"%s\" is not a positive number",
2109 sender_rate_limit);
2110 return ERROR;
2111 }
2112
2113 /* We use the rest of the argument list following the limit as the
2114 lookup key, because it doesn't make sense to use the same stored data
2115 if the period or options are different. */
2116
2117 key = arg;
2118
2119 /* Second is the rate measurement period and exponential smoothing time
2120 constant. This must be strictly greater than zero, because zero leads to
2121 run-time division errors. */
2122
2123 sender_rate_period = string_nextinlist(&arg, &sep, NULL, 0);
2124 if (sender_rate_period == NULL) period = -1.0;
2125 else period = readconf_readtime(sender_rate_period, 0, FALSE);
2126 if (period <= 0.0)
2127 {
2128 *log_msgptr = string_sprintf("syntax error in argument for "
2129 "\"ratelimit\" condition: \"%s\" is not a time value",
2130 sender_rate_period);
2131 return ERROR;
2132 }
2133
2134 /* Parse the other options. Should we check if the per_* options are being
2135 used in ACLs where they don't make sense, e.g. per_mail in the connect ACL? */
2136
2137 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2138 != NULL)
2139 {
2140 if (strcmpic(ss, US"leaky") == 0) leaky = TRUE;
2141 else if (strcmpic(ss, US"strict") == 0) strict = TRUE;
2142 else if (strcmpic(ss, US"per_byte") == 0) per_byte = TRUE;
2143 else if (strcmpic(ss, US"per_cmd") == 0) per_cmd = TRUE;
2144 else if (strcmpic(ss, US"per_conn") == 0) per_conn = TRUE;
2145 else if (strcmpic(ss, US"per_mail") == 0) per_mail = TRUE;
2146 else if (strcmpic(ss, US"per_rcpt") == 0) per_cmd = TRUE; /* alias */
2147 else have_key = TRUE;
2148 }
2149 if (leaky + strict > 1 || per_byte + per_cmd + per_conn + per_mail > 1)
2150 {
2151 *log_msgptr = US"conflicting options for \"ratelimit\" condition";
2152 return ERROR;
2153 }
2154
2155 /* Default option values */
2156 if (!strict) leaky = TRUE;
2157 if (!per_byte && !per_cmd && !per_conn) per_mail = TRUE;
2158
2159 /* If there is no explicit key, use the sender_host_address. If there is no
2160 sender_host_address (e.g. -bs or acl_not_smtp) then we simply omit it. */
2161
2162 if (!have_key && sender_host_address != NULL)
2163 key = string_sprintf("%s / %s", key, sender_host_address);
2164
2165 HDEBUG(D_acl) debug_printf("ratelimit condition limit=%.0f period=%.0f key=%s\n",
2166 limit, period, key);
2167
2168 /* See if we have already computed the rate by looking in the relevant tree. For
2169 per-connection rate limiting, store tree nodes and dbdata in the permanent pool
2170 so that they survive across resets. */
2171
2172 anchor = NULL;
2173 old_pool = store_pool;
2174
2175 if (per_conn)
2176 {
2177 anchor = &ratelimiters_conn;
2178 store_pool = POOL_PERM;
2179 }
2180 else if (per_mail || per_byte)
2181 anchor = &ratelimiters_mail;
2182 else if (per_cmd)
2183 anchor = &ratelimiters_cmd;
2184
2185 if (anchor != NULL && (t = tree_search(*anchor, key)) != NULL)
2186 {
2187 dbd = t->data.ptr;
2188 /* The following few lines duplicate some of the code below. */
2189 if (dbd->rate < limit) rc = FAIL;
2190 else rc = OK;
2191 store_pool = old_pool;
2192 sender_rate = string_sprintf("%.1f", dbd->rate);
2193 HDEBUG(D_acl)
2194 debug_printf("ratelimit found pre-computed rate %s\n", sender_rate);
2195 return rc;
2196 }
2197
2198 /* We aren't using a pre-computed rate, so get a previously recorded
2199 rate from the database, update it, and write it back. If there's no
2200 previous rate for this key, create one. */
2201
2202 dbm = dbfn_open(US"ratelimit", O_RDWR, &dbblock, TRUE);
2203 if (dbm == NULL)
2204 {
2205 store_pool = old_pool;
2206 sender_rate = NULL;
2207 HDEBUG(D_acl) debug_printf("ratelimit database not available\n");
2208 *log_msgptr = US"ratelimit database not available";
2209 return DEFER;
2210 }
2211 dbd = dbfn_read(dbm, key);
2212
2213 gettimeofday(&tv, NULL);
2214
2215 if (dbd == NULL)
2216 {
2217 HDEBUG(D_acl) debug_printf("ratelimit initializing new key's data\n");
2218 dbd = store_get(sizeof(dbdata_ratelimit));
2219 dbd->time_stamp = tv.tv_sec;
2220 dbd->time_usec = tv.tv_usec;
2221 dbd->rate = 0.0;
2222 }
2223 else
2224 {
2225 /* The smoothed rate is computed using an exponentially weighted moving
2226 average adjusted for variable sampling intervals. The standard EWMA for
2227 a fixed sampling interval is: f'(t) = (1 - a) * f(t) + a * f'(t - 1)
2228 where f() is the measured value and f'() is the smoothed value.
2229
2230 Old data decays out of the smoothed value exponentially, such that data n
2231 samples old is multiplied by a^n. The exponential decay time constant p
2232 is defined such that data p samples old is multiplied by 1/e, which means
2233 that a = exp(-1/p). We can maintain the same time constant for a variable
2234 sampling interval i by using a = exp(-i/p).
2235
2236 The rate we are measuring is messages per period, suitable for directly
2237 comparing with the limit. The average rate between now and the previous
2238 message is period / interval, which we feed into the EWMA as the sample.
2239
2240 It turns out that the number of messages required for the smoothed rate
2241 to reach the limit when they are sent in a burst is equal to the limit.
2242 This can be seen by analysing the value of the smoothed rate after N
2243 messages sent at even intervals. Let k = (1 - a) * p/i
2244
2245 rate_1 = (1 - a) * p/i + a * rate_0
2246 = k + a * rate_0
2247 rate_2 = k + a * rate_1
2248 = k + a * k + a^2 * rate_0
2249 rate_3 = k + a * k + a^2 * k + a^3 * rate_0
2250 rate_N = rate_0 * a^N + k * SUM(x=0..N-1)(a^x)
2251 = rate_0 * a^N + k * (1 - a^N) / (1 - a)
2252 = rate_0 * a^N + p/i * (1 - a^N)
2253
2254 When N is large, a^N -> 0 so rate_N -> p/i as desired.
2255
2256 rate_N = p/i + (rate_0 - p/i) * a^N
2257 a^N = (rate_N - p/i) / (rate_0 - p/i)
2258 N * -i/p = log((rate_N - p/i) / (rate_0 - p/i))
2259 N = p/i * log((rate_0 - p/i) / (rate_N - p/i))
2260
2261 Numerical analysis of the above equation, setting the computed rate to
2262 increase from rate_0 = 0 to rate_N = limit, shows that for large sending
2263 rates, p/i, the number of messages N = limit. So limit serves as both the
2264 maximum rate measured in messages per period, and the maximum number of
2265 messages that can be sent in a fast burst. */
2266
2267 double this_time = (double)tv.tv_sec
2268 + (double)tv.tv_usec / 1000000.0;
2269 double prev_time = (double)dbd->time_stamp
2270 + (double)dbd->time_usec / 1000000.0;
2271
2272 /* We must avoid division by zero, and deal gracefully with the clock going
2273 backwards. If we blunder ahead when time is in reverse then the computed
2274 rate will be bogus. To be safe we clamp interval to a very small number. */
2275
2276 double interval = this_time - prev_time <= 0.0 ? 1e-9
2277 : this_time - prev_time;
2278
2279 double i_over_p = interval / period;
2280 double a = exp(-i_over_p);
2281
2282 dbd->time_stamp = tv.tv_sec;
2283 dbd->time_usec = tv.tv_usec;
2284
2285 /* If we are measuring the rate in bytes per period, multiply the
2286 measured rate by the message size. If we don't know the message size
2287 then it's safe to just use a value of zero and let the recorded rate
2288 decay as if nothing happened. */
2289
2290 if (per_byte)
2291 dbd->rate = (message_size < 0 ? 0.0 : (double)message_size)
2292 * (1 - a) / i_over_p + a * dbd->rate;
2293 else if (per_cmd && where == ACL_WHERE_NOTSMTP)
2294 dbd->rate = (double)recipients_count
2295 * (1 - a) / i_over_p + a * dbd->rate;
2296 else
2297 dbd->rate = (1 - a) / i_over_p + a * dbd->rate;
2298 }
2299
2300 /* Clients sending at the limit are considered to be over the limit. This
2301 matters for edge cases such the first message sent by a client (which gets
2302 the initial rate of 0.0) when the rate limit is zero (i.e. the client should
2303 be completely blocked). */
2304
2305 if (dbd->rate < limit) rc = FAIL;
2306 else rc = OK;
2307
2308 /* Update the state if the rate is low or if we are being strict. If we
2309 are in leaky mode and the sender's rate is too high, we do not update
2310 the recorded rate in order to avoid an over-aggressive sender's retry
2311 rate preventing them from getting any email through. */
2312
2313 if (rc == FAIL || !leaky)
2314 dbfn_write(dbm, key, dbd, sizeof(dbdata_ratelimit));
2315 dbfn_close(dbm);
2316
2317 /* Store the result in the tree for future reference, if necessary. */
2318
2319 if (anchor != NULL)
2320 {
2321 t = store_get(sizeof(tree_node) + Ustrlen(key));
2322 t->data.ptr = dbd;
2323 Ustrcpy(t->name, key);
2324 (void)tree_insertnode(anchor, t);
2325 }
2326
2327 /* We create the formatted version of the sender's rate very late in
2328 order to ensure that it is done using the correct storage pool. */
2329
2330 store_pool = old_pool;
2331 sender_rate = string_sprintf("%.1f", dbd->rate);
2332
2333 HDEBUG(D_acl)
2334 debug_printf("ratelimit computed rate %s\n", sender_rate);
2335
2336 return rc;
2337 }
2338
2339
2340
2341 /*************************************************
2342 * Handle conditions/modifiers on an ACL item *
2343 *************************************************/
2344
2345 /* Called from acl_check() below.
2346
2347 Arguments:
2348 verb ACL verb
2349 cb ACL condition block - if NULL, result is OK
2350 where where called from
2351 addr the address being checked for RCPT, or NULL
2352 level the nesting level
2353 epp pointer to pass back TRUE if "endpass" encountered
2354 (applies only to "accept" and "discard")
2355 user_msgptr user message pointer
2356 log_msgptr log message pointer
2357 basic_errno pointer to where to put verify error
2358
2359 Returns: OK - all conditions are met
2360 DISCARD - an "acl" condition returned DISCARD - only allowed
2361 for "accept" or "discard" verbs
2362 FAIL - at least one condition fails
2363 FAIL_DROP - an "acl" condition returned FAIL_DROP
2364 DEFER - can't tell at the moment (typically, lookup defer,
2365 but can be temporary callout problem)
2366 ERROR - ERROR from nested ACL or expansion failure or other
2367 error
2368 */
2369
2370 static int
2371 acl_check_condition(int verb, acl_condition_block *cb, int where,
2372 address_item *addr, int level, BOOL *epp, uschar **user_msgptr,
2373 uschar **log_msgptr, int *basic_errno)
2374 {
2375 uschar *user_message = NULL;
2376 uschar *log_message = NULL;
2377 uschar *p = NULL;
2378 int rc = OK;
2379 #ifdef WITH_CONTENT_SCAN
2380 int sep = '/';
2381 #endif
2382
2383 for (; cb != NULL; cb = cb->next)
2384 {
2385 uschar *arg;
2386 int control_type;
2387
2388 /* The message and log_message items set up messages to be used in
2389 case of rejection. They are expanded later. */
2390
2391 if (cb->type == ACLC_MESSAGE)
2392 {
2393 user_message = cb->arg;
2394 continue;
2395 }
2396
2397 if (cb->type == ACLC_LOG_MESSAGE)
2398 {
2399 log_message = cb->arg;
2400 continue;
2401 }
2402
2403 /* The endpass "condition" just sets a flag to show it occurred. This is
2404 checked at compile time to be on an "accept" or "discard" item. */
2405
2406 if (cb->type == ACLC_ENDPASS)
2407 {
2408 *epp = TRUE;
2409 continue;
2410 }
2411
2412 /* For other conditions and modifiers, the argument is expanded now for some
2413 of them, but not for all, because expansion happens down in some lower level
2414 checking functions in some cases. */
2415
2416 if (cond_expand_at_top[cb->type])
2417 {
2418 arg = expand_string(cb->arg);
2419 if (arg == NULL)
2420 {
2421 if (expand_string_forcedfail) continue;
2422 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s",
2423 cb->arg, expand_string_message);
2424 return search_find_defer? DEFER : ERROR;
2425 }
2426 }
2427 else arg = cb->arg;
2428
2429 /* Show condition, and expanded condition if it's different */
2430
2431 HDEBUG(D_acl)
2432 {
2433 int lhswidth = 0;
2434 debug_printf("check %s%s %n",
2435 (!cond_modifiers[cb->type] && cb->u.negated)? "!":"",
2436 conditions[cb->type], &lhswidth);
2437
2438 if (cb->type == ACLC_SET)
2439 {
2440 debug_printf("acl_%s ", cb->u.varname);
2441 lhswidth += 5 + Ustrlen(cb->u.varname);
2442 }
2443
2444 debug_printf("= %s\n", cb->arg);
2445
2446 if (arg != cb->arg)
2447 debug_printf("%.*s= %s\n", lhswidth,
2448 US" ", CS arg);
2449 }
2450
2451 /* Check that this condition makes sense at this time */
2452
2453 if ((cond_forbids[cb->type] & (1 << where)) != 0)
2454 {
2455 *log_msgptr = string_sprintf("cannot %s %s condition in %s ACL",
2456 cond_modifiers[cb->type]? "use" : "test",
2457 conditions[cb->type], acl_wherenames[where]);
2458 return ERROR;
2459 }
2460
2461 /* Run the appropriate test for each condition, or take the appropriate
2462 action for the remaining modifiers. */
2463
2464 switch(cb->type)
2465 {
2466 case ACLC_ADD_HEADER:
2467 setup_header(arg);
2468 break;
2469
2470 /* A nested ACL that returns "discard" makes sense only for an "accept" or
2471 "discard" verb. */
2472
2473 case ACLC_ACL:
2474 rc = acl_check_internal(where, addr, arg, level+1, user_msgptr, log_msgptr);
2475 if (rc == DISCARD && verb != ACL_ACCEPT && verb != ACL_DISCARD)
2476 {
2477 *log_msgptr = string_sprintf("nested ACL returned \"discard\" for "
2478 "\"%s\" command (only allowed with \"accept\" or \"discard\")",
2479 verbs[verb]);
2480 return ERROR;
2481 }
2482 break;
2483
2484 case ACLC_AUTHENTICATED:
2485 rc = (sender_host_authenticated == NULL)? FAIL :
2486 match_isinlist(sender_host_authenticated, &arg, 0, NULL, NULL, MCL_STRING,
2487 TRUE, NULL);
2488 break;
2489
2490 #ifdef EXPERIMENTAL_BRIGHTMAIL
2491 case ACLC_BMI_OPTIN:
2492 {
2493 int old_pool = store_pool;
2494 store_pool = POOL_PERM;
2495 bmi_current_optin = string_copy(arg);
2496 store_pool = old_pool;
2497 }
2498 break;
2499 #endif
2500
2501 case ACLC_CONDITION:
2502 if (Ustrspn(arg, "0123456789") == Ustrlen(arg)) /* Digits, or empty */
2503 rc = (Uatoi(arg) == 0)? FAIL : OK;
2504 else
2505 rc = (strcmpic(arg, US"no") == 0 ||
2506 strcmpic(arg, US"false") == 0)? FAIL :
2507 (strcmpic(arg, US"yes") == 0 ||
2508 strcmpic(arg, US"true") == 0)? OK : DEFER;
2509 if (rc == DEFER)
2510 *log_msgptr = string_sprintf("invalid \"condition\" value \"%s\"", arg);
2511 break;
2512
2513 case ACLC_CONTROL:
2514 control_type = decode_control(arg, &p, where, log_msgptr);
2515
2516 /* Check if this control makes sense at this time */
2517
2518 if ((control_forbids[control_type] & (1 << where)) != 0)
2519 {
2520 *log_msgptr = string_sprintf("cannot use \"control=%s\" in %s ACL",
2521 controls[control_type], acl_wherenames[where]);
2522 return ERROR;
2523 }
2524
2525 switch(control_type)
2526 {
2527 case CONTROL_AUTH_UNADVERTISED:
2528 allow_auth_unadvertised = TRUE;
2529 break;
2530
2531 #ifdef EXPERIMENTAL_BRIGHTMAIL
2532 case CONTROL_BMI_RUN:
2533 bmi_run = 1;
2534 break;
2535 #endif
2536
2537 #ifdef EXPERIMENTAL_DOMAINKEYS
2538 case CONTROL_DK_VERIFY:
2539 dk_do_verify = 1;
2540 break;
2541 #endif
2542
2543 case CONTROL_ERROR:
2544 return ERROR;
2545
2546 case CONTROL_CASEFUL_LOCAL_PART:
2547 deliver_localpart = addr->cc_local_part;
2548 break;
2549
2550 case CONTROL_CASELOWER_LOCAL_PART:
2551 deliver_localpart = addr->lc_local_part;
2552 break;
2553
2554 case CONTROL_ENFORCE_SYNC:
2555 smtp_enforce_sync = TRUE;
2556 break;
2557
2558 case CONTROL_NO_ENFORCE_SYNC:
2559 smtp_enforce_sync = FALSE;
2560 break;
2561
2562 #ifdef WITH_CONTENT_SCAN
2563 case CONTROL_NO_MBOX_UNSPOOL:
2564 no_mbox_unspool = TRUE;
2565 break;
2566 #endif
2567
2568 case CONTROL_NO_MULTILINE:
2569 no_multiline_responses = TRUE;
2570 break;
2571
2572 case CONTROL_FAKEDEFER:
2573 case CONTROL_FAKEREJECT:
2574 fake_response = (control_type == CONTROL_FAKEDEFER) ? DEFER : FAIL;
2575 if (*p == '/')
2576 {
2577 uschar *pp = p + 1;
2578 while (*pp != 0) pp++;
2579 fake_response_text = expand_string(string_copyn(p+1, pp-p-1));
2580 p = pp;
2581 }
2582 else
2583 {
2584 /* Explicitly reset to default string */
2585 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).";
2586 }
2587 break;
2588
2589 case CONTROL_FREEZE:
2590 deliver_freeze = TRUE;
2591 deliver_frozen_at = time(NULL);
2592 freeze_tell = freeze_tell_config; /* Reset to configured value */
2593 if (Ustrncmp(p, "/no_tell", 8) == 0)
2594 {
2595 p += 8;
2596 freeze_tell = NULL;
2597 }
2598 if (*p != 0)
2599 {
2600 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
2601 return ERROR;
2602 }
2603 break;
2604
2605 case CONTROL_QUEUE_ONLY:
2606 queue_only_policy = TRUE;
2607 break;
2608
2609 case CONTROL_SUBMISSION:
2610 originator_name = US"";
2611 submission_mode = TRUE;
2612 while (*p == '/')
2613 {
2614 if (Ustrncmp(p, "/sender_retain", 14) == 0)
2615 {
2616 p += 14;
2617 active_local_sender_retain = TRUE;
2618 active_local_from_check = FALSE;
2619 }
2620 else if (Ustrncmp(p, "/domain=", 8) == 0)
2621 {
2622 uschar *pp = p + 8;
2623 while (*pp != 0 && *pp != '/') pp++;
2624 submission_domain = string_copyn(p+8, pp-p-8);
2625 p = pp;
2626 }
2627 /* The name= option must be last, because it swallows the rest of
2628 the string. */
2629 else if (Ustrncmp(p, "/name=", 6) == 0)
2630 {
2631 uschar *pp = p + 6;
2632 while (*pp != 0) pp++;
2633 submission_name = string_copy(parse_fix_phrase(p+6, pp-p-6,
2634 big_buffer, big_buffer_size));
2635 p = pp;
2636 }
2637 else break;
2638 }
2639 if (*p != 0)
2640 {
2641 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
2642 return ERROR;
2643 }
2644 break;
2645
2646 case CONTROL_SUPPRESS_LOCAL_FIXUPS:
2647 suppress_local_fixups = TRUE;
2648 break;
2649 }
2650 break;
2651
2652 #ifdef WITH_CONTENT_SCAN
2653 case ACLC_DECODE:
2654 rc = mime_decode(&arg);
2655 break;
2656 #endif
2657
2658 case ACLC_DELAY:
2659 {
2660 int delay = readconf_readtime(arg, 0, FALSE);
2661 if (delay < 0)
2662 {
2663 *log_msgptr = string_sprintf("syntax error in argument for \"delay\" "
2664 "modifier: \"%s\" is not a time value", arg);
2665 return ERROR;
2666 }
2667 else
2668 {
2669 HDEBUG(D_acl) debug_printf("delay modifier requests %d-second delay\n",
2670 delay);
2671 if (host_checking)
2672 {
2673 HDEBUG(D_acl)
2674 debug_printf("delay skipped in -bh checking mode\n");
2675 }
2676
2677 /* It appears to be impossible to detect that a TCP/IP connection has
2678 gone away without reading from it. This means that we cannot shorten
2679 the delay below if the client goes away, because we cannot discover
2680 that the client has closed its end of the connection. (The connection
2681 is actually in a half-closed state, waiting for the server to close its
2682 end.) It would be nice to be able to detect this state, so that the
2683 Exim process is not held up unnecessarily. However, it seems that we
2684 can't. The poll() function does not do the right thing, and in any case
2685 it is not always available.
2686
2687 NOTE: If ever this state of affairs changes, remember that we may be
2688 dealing with stdin/stdout here, in addition to TCP/IP connections.
2689 Whatever is done must work in both cases. To detected the stdin/stdout
2690 case, check for smtp_in or smtp_out being NULL. */
2691
2692 else
2693 {
2694 while (delay > 0) delay = sleep(delay);
2695 }
2696 }
2697 }
2698 break;
2699
2700 #ifdef WITH_OLD_DEMIME
2701 case ACLC_DEMIME:
2702 rc = demime(&arg);
2703 break;
2704 #endif
2705
2706 #ifdef EXPERIMENTAL_DOMAINKEYS
2707 case ACLC_DK_DOMAIN_SOURCE:
2708 if (dk_verify_block == NULL) { rc = FAIL; break; };
2709 /* check header source of domain against given string */
2710 switch (dk_verify_block->address_source) {
2711 case DK_EXIM_ADDRESS_FROM_FROM:
2712 rc = match_isinlist(US"from", &arg, 0, NULL,
2713 NULL, MCL_STRING, TRUE, NULL);
2714 break;
2715 case DK_EXIM_ADDRESS_FROM_SENDER:
2716 rc = match_isinlist(US"sender", &arg, 0, NULL,
2717 NULL, MCL_STRING, TRUE, NULL);
2718 break;
2719 case DK_EXIM_ADDRESS_NONE:
2720 rc = match_isinlist(US"none", &arg, 0, NULL,
2721 NULL, MCL_STRING, TRUE, NULL);
2722 break;
2723 }
2724 break;
2725
2726 case ACLC_DK_POLICY:
2727 if (dk_verify_block == NULL) { rc = FAIL; break; };
2728 /* check policy against given string, default FAIL */
2729 rc = FAIL;
2730 if (dk_verify_block->signsall)
2731 rc = match_isinlist(US"signsall", &arg, 0, NULL,
2732 NULL, MCL_STRING, TRUE, NULL);
2733 if (dk_verify_block->testing)
2734 rc = match_isinlist(US"testing", &arg, 0, NULL,
2735 NULL, MCL_STRING, TRUE, NULL);
2736 break;
2737
2738 case ACLC_DK_SENDER_DOMAINS:
2739 if (dk_verify_block == NULL) { rc = FAIL; break; };
2740 if (dk_verify_block->domain != NULL)
2741 rc = match_isinlist(dk_verify_block->domain, &arg, 0, &domainlist_anchor,
2742 NULL, MCL_DOMAIN, TRUE, NULL);
2743 else rc = FAIL;
2744 break;
2745
2746 case ACLC_DK_SENDER_LOCAL_PARTS:
2747 if (dk_verify_block == NULL) { rc = FAIL; break; };
2748 if (dk_verify_block->local_part != NULL)
2749 rc = match_isinlist(dk_verify_block->local_part, &arg, 0, &localpartlist_anchor,
2750 NULL, MCL_LOCALPART, TRUE, NULL);
2751 else rc = FAIL;
2752 break;
2753
2754 case ACLC_DK_SENDERS:
2755 if (dk_verify_block == NULL) { rc = FAIL; break; };
2756 if (dk_verify_block->address != NULL)
2757 rc = match_address_list(dk_verify_block->address, TRUE, TRUE, &arg, NULL, -1, 0, NULL);
2758 else rc = FAIL;
2759 break;
2760
2761 case ACLC_DK_STATUS:
2762 if (dk_verify_block == NULL) { rc = FAIL; break; };
2763 if (dk_verify_block->result > 0) {
2764 switch(dk_verify_block->result) {
2765 case DK_EXIM_RESULT_BAD_FORMAT:
2766 rc = match_isinlist(US"bad format", &arg, 0, NULL,
2767 NULL, MCL_STRING, TRUE, NULL);
2768 break;
2769 case DK_EXIM_RESULT_NO_KEY:
2770 rc = match_isinlist(US"no key", &arg, 0, NULL,
2771 NULL, MCL_STRING, TRUE, NULL);
2772 break;
2773 case DK_EXIM_RESULT_NO_SIGNATURE:
2774 rc = match_isinlist(US"no signature", &arg, 0, NULL,
2775 NULL, MCL_STRING, TRUE, NULL);
2776 break;
2777 case DK_EXIM_RESULT_REVOKED:
2778 rc = match_isinlist(US"revoked", &arg, 0, NULL,
2779 NULL, MCL_STRING, TRUE, NULL);
2780 break;
2781 case DK_EXIM_RESULT_NON_PARTICIPANT:
2782 rc = match_isinlist(US"non-participant", &arg, 0, NULL,
2783 NULL, MCL_STRING, TRUE, NULL);
2784 break;
2785 case DK_EXIM_RESULT_GOOD:
2786 rc = match_isinlist(US"good", &arg, 0, NULL,
2787 NULL, MCL_STRING, TRUE, NULL);
2788 break;
2789 case DK_EXIM_RESULT_BAD:
2790 rc = match_isinlist(US"bad", &arg, 0, NULL,
2791 NULL, MCL_STRING, TRUE, NULL);
2792 break;
2793 }
2794 }
2795 break;
2796 #endif
2797
2798 case ACLC_DNSLISTS:
2799 rc = verify_check_dnsbl(&arg);
2800 break;
2801
2802 case ACLC_DOMAINS:
2803 rc = match_isinlist(addr->domain, &arg, 0, &domainlist_anchor,
2804 addr->domain_cache, MCL_DOMAIN, TRUE, &deliver_domain_data);
2805 break;
2806
2807 /* The value in tls_cipher is the full cipher name, for example,
2808 TLSv1:DES-CBC3-SHA:168, whereas the values to test for are just the
2809 cipher names such as DES-CBC3-SHA. But program defensively. We don't know
2810 what may in practice come out of the SSL library - which at the time of
2811 writing is poorly documented. */
2812
2813 case ACLC_ENCRYPTED:
2814 if (tls_cipher == NULL) rc = FAIL; else
2815 {
2816 uschar *endcipher = NULL;
2817 uschar *cipher = Ustrchr(tls_cipher, ':');
2818 if (cipher == NULL) cipher = tls_cipher; else
2819 {
2820 endcipher = Ustrchr(++cipher, ':');
2821 if (endcipher != NULL) *endcipher = 0;
2822 }
2823 rc = match_isinlist(cipher, &arg, 0, NULL, NULL, MCL_STRING, TRUE, NULL);
2824 if (endcipher != NULL) *endcipher = ':';
2825 }
2826 break;
2827
2828 /* Use verify_check_this_host() instead of verify_check_host() so that
2829 we can pass over &host_data to catch any looked up data. Once it has been
2830 set, it retains its value so that it's still there if another ACL verb
2831 comes through here and uses the cache. However, we must put it into
2832 permanent store in case it is also expected to be used in a subsequent
2833 message in the same SMTP connection. */
2834
2835 case ACLC_HOSTS:
2836 rc = verify_check_this_host(&arg, sender_host_cache, NULL,
2837 (sender_host_address == NULL)? US"" : sender_host_address, &host_data);
2838 if (host_data != NULL) host_data = string_copy_malloc(host_data);
2839 break;
2840
2841 case ACLC_LOCAL_PARTS:
2842 rc = match_isinlist(addr->cc_local_part, &arg, 0,
2843 &localpartlist_anchor, addr->localpart_cache, MCL_LOCALPART, TRUE,
2844 &deliver_localpart_data);
2845 break;
2846
2847 case ACLC_LOGWRITE:
2848 {
2849 int logbits = 0;
2850 uschar *s = arg;
2851 if (*s == ':')
2852 {
2853 s++;
2854 while (*s != ':')
2855 {
2856 if (Ustrncmp(s, "main", 4) == 0)
2857 { logbits |= LOG_MAIN; s += 4; }
2858 else if (Ustrncmp(s, "panic", 5) == 0)
2859 { logbits |= LOG_PANIC; s += 5; }
2860 else if (Ustrncmp(s, "reject", 6) == 0)
2861 { logbits |= LOG_REJECT; s += 6; }
2862 else
2863 {
2864 logbits = LOG_MAIN|LOG_PANIC;
2865 s = string_sprintf(":unknown log name in \"%s\" in "
2866 "\"logwrite\" in %s ACL", arg, acl_wherenames[where]);
2867 }
2868 if (*s == ',') s++;
2869 }
2870 s++;
2871 }
2872 while (isspace(*s)) s++;
2873 if (logbits == 0) logbits = LOG_MAIN;
2874 log_write(0, logbits, "%s", string_printing(s));
2875 }
2876 break;
2877
2878 #ifdef WITH_CONTENT_SCAN
2879 case ACLC_MALWARE:
2880 {
2881 /* Seperate the regular expression and any optional parameters. */
2882 uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size);
2883 /* Run the malware backend. */
2884 rc = malware(&ss);
2885 /* Modify return code based upon the existance of options. */
2886 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2887 != NULL) {
2888 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
2889 {
2890 /* FAIL so that the message is passed to the next ACL */
2891 rc = FAIL;
2892 }
2893 }
2894 }
2895 break;
2896
2897 case ACLC_MIME_REGEX:
2898 rc = mime_regex(&arg);
2899 break;
2900 #endif
2901
2902 case ACLC_RATELIMIT:
2903 rc = acl_ratelimit(arg, where, log_msgptr);
2904 break;
2905
2906 case ACLC_RECIPIENTS:
2907 rc = match_address_list(addr->address, TRUE, TRUE, &arg, NULL, -1, 0,
2908 &recipient_data);
2909 break;
2910
2911 #ifdef WITH_CONTENT_SCAN
2912 case ACLC_REGEX:
2913 rc = regex(&arg);
2914 break;
2915 #endif
2916
2917 case ACLC_SENDER_DOMAINS:
2918 {
2919 uschar *sdomain;
2920 sdomain = Ustrrchr(sender_address, '@');
2921 sdomain = (sdomain == NULL)? US"" : sdomain + 1;
2922 rc = match_isinlist(sdomain, &arg, 0, &domainlist_anchor,
2923 sender_domain_cache, MCL_DOMAIN, TRUE, NULL);
2924 }
2925 break;
2926
2927 case ACLC_SENDERS:
2928 rc = match_address_list(sender_address, TRUE, TRUE, &arg,
2929 sender_address_cache, -1, 0, &sender_data);
2930 break;
2931
2932 /* Connection variables must persist forever */
2933
2934 case ACLC_SET:
2935 {
2936 int old_pool = store_pool;
2937 if (cb->u.varname[0] == 'c') store_pool = POOL_PERM;
2938 acl_var_create(cb->u.varname)->data.ptr = string_copy(arg);
2939 store_pool = old_pool;
2940 }
2941 break;
2942
2943 #ifdef WITH_CONTENT_SCAN
2944 case ACLC_SPAM:
2945 {
2946 /* Seperate the regular expression and any optional parameters. */
2947 uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size);
2948 /* Run the spam backend. */
2949 rc = spam(&ss);
2950 /* Modify return code based upon the existance of options. */
2951 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2952 != NULL) {
2953 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
2954 {
2955 /* FAIL so that the message is passed to the next ACL */
2956 rc = FAIL;
2957 }
2958 }
2959 }
2960 break;
2961 #endif
2962
2963 #ifdef EXPERIMENTAL_SPF
2964 case ACLC_SPF:
2965 rc = spf_process(&arg, sender_address);
2966 break;
2967 #endif
2968
2969 /* If the verb is WARN, discard any user message from verification, because
2970 such messages are SMTP responses, not header additions. The latter come
2971 only from explicit "message" modifiers. However, put the user message into
2972 $acl_verify_message so it can be used in subsequent conditions or modifiers
2973 (until something changes it). */
2974
2975 case ACLC_VERIFY:
2976 rc = acl_verify(where, addr, arg, user_msgptr, log_msgptr, basic_errno);
2977 acl_verify_message = *user_msgptr;
2978 if (verb == ACL_WARN) *user_msgptr = NULL;
2979 break;
2980
2981 default:
2982 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown "
2983 "condition %d", cb->type);
2984 break;
2985 }
2986
2987 /* If a condition was negated, invert OK/FAIL. */
2988
2989 if (!cond_modifiers[cb->type] && cb->u.negated)
2990 {
2991 if (rc == OK) rc = FAIL;
2992 else if (rc == FAIL || rc == FAIL_DROP) rc = OK;
2993 }
2994
2995 if (rc != OK) break; /* Conditions loop */
2996 }
2997
2998
2999 /* If the result is the one for which "message" and/or "log_message" are used,
3000 handle the values of these options. Most verbs have but a single return for
3001 which the messages are relevant, but for "discard", it's useful to have the log
3002 message both when it succeeds and when it fails. Also, for an "accept" that
3003 appears in a QUIT ACL, we want to handle the user message. Since only "accept"
3004 and "warn" are permitted in that ACL, we don't need to test the verb.
3005
3006 These modifiers act in different ways:
3007
3008 "message" is a user message that will be included in an SMTP response. Unless
3009 it is empty, it overrides any previously set user message.
3010
3011 "log_message" is a non-user message, and it adds to any existing non-user
3012 message that is already set.
3013
3014 If there isn't a log message set, we make it the same as the user message. */
3015
3016 if (((rc == FAIL_DROP)? FAIL : rc) == msgcond[verb] ||
3017 (verb == ACL_DISCARD && rc == OK) ||
3018 (where == ACL_WHERE_QUIT))
3019 {
3020 uschar *expmessage;
3021
3022 /* If the verb is "warn", messages generated by conditions (verification or
3023 nested ACLs) are discarded. Only messages specified at this level are used.
3024 However, the value of an existing message is available in $acl_verify_message
3025 during expansions. */
3026
3027 uschar *old_user_msgptr = *user_msgptr;
3028 uschar *old_log_msgptr = (*log_msgptr != NULL)? *log_msgptr : old_user_msgptr;
3029
3030 if (verb == ACL_WARN) *log_msgptr = *user_msgptr = NULL;
3031
3032 if (user_message != NULL)
3033 {
3034 acl_verify_message = old_user_msgptr;
3035 expmessage = expand_string(user_message);
3036 if (expmessage == NULL)
3037 {
3038 if (!expand_string_forcedfail)
3039 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
3040 user_message, expand_string_message);
3041 }
3042 else if (expmessage[0] != 0) *user_msgptr = expmessage;
3043 }
3044
3045 if (log_message != NULL)
3046 {
3047 acl_verify_message = old_log_msgptr;
3048 expmessage = expand_string(log_message);
3049 if (expmessage == NULL)
3050 {
3051 if (!expand_string_forcedfail)
3052 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
3053 log_message, expand_string_message);
3054 }
3055 else if (expmessage[0] != 0)
3056 {
3057 *log_msgptr = (*log_msgptr == NULL)? expmessage :
3058 string_sprintf("%s: %s", expmessage, *log_msgptr);
3059 }
3060 }
3061
3062 /* If no log message, default it to the user message */
3063
3064 if (*log_msgptr == NULL) *log_msgptr = *user_msgptr;
3065 }
3066
3067 acl_verify_message = NULL;
3068 return rc;
3069 }
3070
3071
3072
3073
3074
3075 /*************************************************
3076 * Get line from a literal ACL *
3077 *************************************************/
3078
3079 /* This function is passed to acl_read() in order to extract individual lines
3080 of a literal ACL, which we access via static pointers. We can destroy the
3081 contents because this is called only once (the compiled ACL is remembered).
3082
3083 This code is intended to treat the data in the same way as lines in the main
3084 Exim configuration file. That is:
3085
3086 . Leading spaces are ignored.
3087
3088 . A \ at the end of a line is a continuation - trailing spaces after the \
3089 are permitted (this is because I don't believe in making invisible things
3090 significant). Leading spaces on the continued part of a line are ignored.
3091
3092 . Physical lines starting (significantly) with # are totally ignored, and
3093 may appear within a sequence of backslash-continued lines.
3094
3095 . Blank lines are ignored, but will end a sequence of continuations.
3096
3097 Arguments: none
3098 Returns: a pointer to the next line
3099 */
3100
3101
3102 static uschar *acl_text; /* Current pointer in the text */
3103 static uschar *acl_text_end; /* Points one past the terminating '0' */
3104
3105
3106 static uschar *
3107 acl_getline(void)
3108 {
3109 uschar *yield;
3110
3111 /* This loop handles leading blank lines and comments. */
3112
3113 for(;;)
3114 {
3115 while (isspace(*acl_text)) acl_text++; /* Leading spaces/empty lines */
3116 if (*acl_text == 0) return NULL; /* No more data */
3117 yield = acl_text; /* Potential data line */
3118
3119 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3120
3121 /* If we hit the end before a newline, we have the whole logical line. If
3122 it's a comment, there's no more data to be given. Otherwise, yield it. */
3123
3124 if (*acl_text == 0) return (*yield == '#')? NULL : yield;
3125
3126 /* After reaching a newline, end this loop if the physical line does not
3127 start with '#'. If it does, it's a comment, and the loop continues. */
3128
3129 if (*yield != '#') break;
3130 }
3131
3132 /* This loop handles continuations. We know we have some real data, ending in
3133 newline. See if there is a continuation marker at the end (ignoring trailing
3134 white space). We know that *yield is not white space, so no need to test for
3135 cont > yield in the backwards scanning loop. */
3136
3137 for(;;)
3138 {
3139 uschar *cont;
3140 for (cont = acl_text - 1; isspace(*cont); cont--);
3141
3142 /* If no continuation follows, we are done. Mark the end of the line and
3143 return it. */
3144
3145 if (*cont != '\\')
3146 {
3147 *acl_text++ = 0;
3148 return yield;
3149 }
3150
3151 /* We have encountered a continuation. Skip over whitespace at the start of
3152 the next line, and indeed the whole of the next line or lines if they are
3153 comment lines. */
3154
3155 for (;;)
3156 {
3157 while (*(++acl_text) == ' ' || *acl_text == '\t');
3158 if (*acl_text != '#') break;
3159 while (*(++acl_text) != 0 && *acl_text != '\n');
3160 }
3161
3162 /* We have the start of a continuation line. Move all the rest of the data
3163 to join onto the previous line, and then find its end. If the end is not a
3164 newline, we are done. Otherwise loop to look for another continuation. */
3165
3166 memmove(cont, acl_text, acl_text_end - acl_text);
3167 acl_text_end -= acl_text - cont;
3168 acl_text = cont;
3169 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3170 if (*acl_text == 0) return yield;
3171 }
3172
3173 /* Control does not reach here */
3174 }
3175
3176
3177
3178
3179
3180 /*************************************************
3181 * Check access using an ACL *
3182 *************************************************/
3183
3184 /* This function is called from address_check. It may recurse via
3185 acl_check_condition() - hence the use of a level to stop looping. The ACL is
3186 passed as a string which is expanded. A forced failure implies no access check
3187 is required. If the result is a single word, it is taken as the name of an ACL
3188 which is sought in the global ACL tree. Otherwise, it is taken as literal ACL
3189 text, complete with newlines, and parsed as such. In both cases, the ACL check
3190 is then run. This function uses an auxiliary function for acl_read() to call
3191 for reading individual lines of a literal ACL. This is acl_getline(), which
3192 appears immediately above.
3193
3194 Arguments:
3195 where where called from
3196 addr address item when called from RCPT; otherwise NULL
3197 s the input string; NULL is the same as an empty ACL => DENY
3198 level the nesting level
3199 user_msgptr where to put a user error (for SMTP response)
3200 log_msgptr where to put a logging message (not for SMTP response)
3201
3202 Returns: OK access is granted
3203 DISCARD access is apparently granted...
3204 FAIL access is denied
3205 FAIL_DROP access is denied; drop the connection
3206 DEFER can't tell at the moment
3207 ERROR disaster
3208 */
3209
3210 static int
3211 acl_check_internal(int where, address_item *addr, uschar *s, int level,
3212 uschar **user_msgptr, uschar **log_msgptr)
3213 {
3214 int fd = -1;
3215 acl_block *acl = NULL;
3216 uschar *acl_name = US"inline ACL";
3217 uschar *ss;
3218
3219 /* Catch configuration loops */
3220
3221 if (level > 20)
3222 {
3223 *log_msgptr = US"ACL nested too deep: possible loop";
3224 return ERROR;
3225 }
3226
3227 if (s == NULL)
3228 {
3229 HDEBUG(D_acl) debug_printf("ACL is NULL: implicit DENY\n");
3230 return FAIL;
3231 }
3232
3233 /* At top level, we expand the incoming string. At lower levels, it has already
3234 been expanded as part of condition processing. */
3235
3236 if (level == 0)
3237 {
3238 ss = expand_string(s);
3239 if (ss == NULL)
3240 {
3241 if (expand_string_forcedfail) return OK;
3242 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s", s,
3243 expand_string_message);
3244 return ERROR;
3245 }
3246 }
3247 else ss = s;
3248
3249 while (isspace(*ss))ss++;
3250
3251 /* If we can't find a named ACL, the default is to parse it as an inline one.
3252 (Unless it begins with a slash; non-existent files give rise to an error.) */
3253
3254 acl_text = ss;
3255
3256 /* Handle the case of a string that does not contain any spaces. Look for a
3257 named ACL among those read from the configuration, or a previously read file.
3258 It is possible that the pointer to the ACL is NULL if the configuration
3259 contains a name with no data. If not found, and the text begins with '/',
3260 read an ACL from a file, and save it so it can be re-used. */
3261
3262 if (Ustrchr(ss, ' ') == NULL)
3263 {
3264 tree_node *t = tree_search(acl_anchor, ss);
3265 if (t != NULL)
3266 {
3267 acl = (acl_block *)(t->data.ptr);
3268 if (acl == NULL)
3269 {
3270 HDEBUG(D_acl) debug_printf("ACL \"%s\" is empty: implicit DENY\n", ss);
3271 return FAIL;
3272 }
3273 acl_name = string_sprintf("ACL \"%s\"", ss);
3274 HDEBUG(D_acl) debug_printf("using ACL \"%s\"\n", ss);
3275 }
3276
3277 else if (*ss == '/')
3278 {
3279 struct stat statbuf;
3280 fd = Uopen(ss, O_RDONLY, 0);
3281 if (fd < 0)
3282 {
3283 *log_msgptr = string_sprintf("failed to open ACL file \"%s\": %s", ss,
3284 strerror(errno));
3285 return ERROR;
3286 }
3287
3288 if (fstat(fd, &statbuf) != 0)
3289 {
3290 *log_msgptr = string_sprintf("failed to fstat ACL file \"%s\": %s", ss,
3291 strerror(errno));
3292 return ERROR;
3293 }
3294
3295 acl_text = store_get(statbuf.st_size + 1);
3296 acl_text_end = acl_text + statbuf.st_size + 1;
3297
3298 if (read(fd, acl_text, statbuf.st_size) != statbuf.st_size)
3299 {
3300 *log_msgptr = string_sprintf("failed to read ACL file \"%s\": %s",
3301 ss, strerror(errno));
3302 return ERROR;
3303 }
3304 acl_text[statbuf.st_size] = 0;
3305 (void)close(fd);
3306
3307 acl_name = string_sprintf("ACL \"%s\"", ss);
3308 HDEBUG(D_acl) debug_printf("read ACL from file %s\n", ss);
3309 }
3310 }
3311
3312 /* Parse an ACL that is still in text form. If it came from a file, remember it
3313 in the ACL tree, having read it into the POOL_PERM store pool so that it
3314 persists between multiple messages. */
3315
3316 if (acl == NULL)
3317 {
3318 int old_pool = store_pool;
3319 if (fd >= 0) store_pool = POOL_PERM;
3320 acl = acl_read(acl_getline, log_msgptr);
3321 store_pool = old_pool;
3322 if (acl == NULL && *log_msgptr != NULL) return ERROR;
3323 if (fd >= 0)
3324 {
3325 tree_node *t = store_get_perm(sizeof(tree_node) + Ustrlen(ss));
3326 Ustrcpy(t->name, ss);
3327 t->data.ptr = acl;
3328 (void)tree_insertnode(&acl_anchor, t);
3329 }
3330 }
3331
3332 /* Now we have an ACL to use. It's possible it may be NULL. */
3333
3334 while (acl != NULL)
3335 {
3336 int cond;
3337 int basic_errno = 0;
3338 BOOL endpass_seen = FALSE;
3339
3340 *log_msgptr = *user_msgptr = NULL;
3341 acl_temp_details = FALSE;
3342
3343 if (where == ACL_WHERE_QUIT &&
3344 acl->verb != ACL_ACCEPT &&
3345 acl->verb != ACL_WARN)
3346 {
3347 *log_msgptr = string_sprintf("\"%s\" is not allowed in a QUIT ACL",
3348 verbs[acl->verb]);
3349 return ERROR;
3350 }
3351
3352 HDEBUG(D_acl) debug_printf("processing \"%s\"\n", verbs[acl->verb]);
3353
3354 /* Clear out any search error message from a previous check before testing
3355 this condition. */
3356
3357 search_error_message = NULL;
3358 cond = acl_check_condition(acl->verb, acl->condition, where, addr, level,
3359 &endpass_seen, user_msgptr, log_msgptr, &basic_errno);
3360
3361 /* Handle special returns: DEFER causes a return except on a WARN verb;
3362 ERROR always causes a return. */
3363
3364 switch (cond)
3365 {
3366 case DEFER:
3367 HDEBUG(D_acl) debug_printf("%s: condition test deferred\n", verbs[acl->verb]);
3368 if (basic_errno != ERRNO_CALLOUTDEFER)
3369 {
3370 if (search_error_message != NULL && *search_error_message != 0)
3371 *log_msgptr = search_error_message;
3372 if (smtp_return_error_details) acl_temp_details = TRUE;
3373 }
3374 else
3375 {
3376 acl_temp_details = TRUE;
3377 }
3378 if (acl->verb != ACL_WARN) return DEFER;
3379 break;
3380
3381 default: /* Paranoia */
3382 case ERROR:
3383 HDEBUG(D_acl) debug_printf("%s: condition test error\n", verbs[acl->verb]);
3384 return ERROR;
3385
3386 case OK:
3387 HDEBUG(D_acl) debug_printf("%s: condition test succeeded\n",
3388 verbs[acl->verb]);
3389 break;
3390
3391 case FAIL:
3392 HDEBUG(D_acl) debug_printf("%s: condition test failed\n", verbs[acl->verb]);
3393 break;
3394
3395 /* DISCARD and DROP can happen only from a nested ACL condition, and
3396 DISCARD can happen only for an "accept" or "discard" verb. */
3397
3398 case DISCARD:
3399 HDEBUG(D_acl) debug_printf("%s: condition test yielded \"discard\"\n",
3400 verbs[acl->verb]);
3401 break;
3402
3403 case FAIL_DROP:
3404 HDEBUG(D_acl) debug_printf("%s: condition test yielded \"drop\"\n",
3405 verbs[acl->verb]);
3406 break;
3407 }
3408
3409 /* At this point, cond for most verbs is either OK or FAIL or (as a result of
3410 a nested ACL condition) FAIL_DROP. However, for WARN, cond may be DEFER, and
3411 for ACCEPT and DISCARD, it may be DISCARD after a nested ACL call. */
3412
3413 switch(acl->verb)
3414 {
3415 case ACL_ACCEPT:
3416 if (cond == OK || cond == DISCARD) return cond;
3417 if (endpass_seen)
3418 {
3419 HDEBUG(D_acl) debug_printf("accept: endpass encountered - denying access\n");
3420 return cond;
3421 }
3422 break;
3423
3424 case ACL_DEFER:
3425 if (cond == OK)
3426 {
3427 acl_temp_details = TRUE;
3428 return DEFER;
3429 }
3430 break;
3431
3432 case ACL_DENY:
3433 if (cond == OK) return FAIL;
3434 break;
3435
3436 case ACL_DISCARD:
3437 if (cond == OK || cond == DISCARD) return DISCARD;
3438 if (endpass_seen)
3439 {
3440 HDEBUG(D_acl) debug_printf("discard: endpass encountered - denying access\n");
3441 return cond;
3442 }
3443 break;
3444
3445 case ACL_DROP:
3446 if (cond == OK) return FAIL_DROP;
3447 break;
3448
3449 case ACL_REQUIRE:
3450 if (cond != OK) return cond;
3451 break;
3452
3453 case ACL_WARN:
3454 if (cond == OK)
3455 acl_warn(where, *user_msgptr, *log_msgptr);
3456 else if (cond == DEFER && (log_extra_selector & LX_acl_warn_skipped) != 0)
3457 log_write(0, LOG_MAIN, "%s Warning: ACL \"warn\" statement skipped: "
3458 "condition test deferred%s%s", host_and_ident(TRUE),
3459 (*log_msgptr == NULL)? US"" : US": ",
3460 (*log_msgptr == NULL)? US"" : *log_msgptr);
3461 *log_msgptr = *user_msgptr = NULL; /* In case implicit DENY follows */
3462 break;
3463
3464 default: