Add /noupdate as a ratelimit option.
[exim.git] / src / src / acl.c
1 /* $Cambridge: exim/src/src/acl.c,v 1.77 2007/06/20 14:13:39 ph10 Exp $ */
2
3 /*************************************************
4 * Exim - an Internet mail transport agent *
5 *************************************************/
6
7 /* Copyright (c) University of Cambridge 1995 - 2007 */
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 conditions for which "message" or "log_message" are used
31 are held as a bitmap. This is to avoid expanding the strings unnecessarily. For
32 "accept", the FAIL case is used only after "endpass", but that is selected in
33 the code. */
34
35 static int msgcond[] = {
36 (1<<OK) | (1<<FAIL) | (1<<FAIL_DROP), /* accept */
37 (1<<OK), /* defer */
38 (1<<OK), /* deny */
39 (1<<OK) | (1<<FAIL) | (1<<FAIL_DROP), /* discard */
40 (1<<OK), /* drop */
41 (1<<FAIL) | (1<<FAIL_DROP), /* require */
42 (1<<OK) /* warn */
43 };
44
45 /* ACL condition and modifier codes - keep in step with the table that
46 follows, and the cond_expand_at_top and uschar cond_modifiers tables lower
47 down. */
48
49 enum { ACLC_ACL,
50 ACLC_ADD_HEADER,
51 ACLC_AUTHENTICATED,
52 #ifdef EXPERIMENTAL_BRIGHTMAIL
53 ACLC_BMI_OPTIN,
54 #endif
55 ACLC_CONDITION,
56 ACLC_CONTINUE,
57 ACLC_CONTROL,
58 #ifdef WITH_CONTENT_SCAN
59 ACLC_DECODE,
60 #endif
61 ACLC_DELAY,
62 #ifdef WITH_OLD_DEMIME
63 ACLC_DEMIME,
64 #endif
65 #ifdef EXPERIMENTAL_DOMAINKEYS
66 ACLC_DK_DOMAIN_SOURCE,
67 ACLC_DK_POLICY,
68 ACLC_DK_SENDER_DOMAINS,
69 ACLC_DK_SENDER_LOCAL_PARTS,
70 ACLC_DK_SENDERS,
71 ACLC_DK_STATUS,
72 #endif
73 ACLC_DNSLISTS,
74 ACLC_DOMAINS,
75 ACLC_ENCRYPTED,
76 ACLC_ENDPASS,
77 ACLC_HOSTS,
78 ACLC_LOCAL_PARTS,
79 ACLC_LOG_MESSAGE,
80 ACLC_LOG_REJECT_TARGET,
81 ACLC_LOGWRITE,
82 #ifdef WITH_CONTENT_SCAN
83 ACLC_MALWARE,
84 #endif
85 ACLC_MESSAGE,
86 #ifdef WITH_CONTENT_SCAN
87 ACLC_MIME_REGEX,
88 #endif
89 ACLC_RATELIMIT,
90 ACLC_RECIPIENTS,
91 #ifdef WITH_CONTENT_SCAN
92 ACLC_REGEX,
93 #endif
94 ACLC_SENDER_DOMAINS,
95 ACLC_SENDERS,
96 ACLC_SET,
97 #ifdef WITH_CONTENT_SCAN
98 ACLC_SPAM,
99 #endif
100 #ifdef EXPERIMENTAL_SPF
101 ACLC_SPF,
102 #endif
103 ACLC_VERIFY };
104
105 /* ACL conditions/modifiers: "delay", "control", "continue", "endpass",
106 "message", "log_message", "log_reject_target", "logwrite", and "set" are
107 modifiers that look like conditions but always return TRUE. They are used for
108 their side effects. */
109
110 static uschar *conditions[] = {
111 US"acl",
112 US"add_header",
113 US"authenticated",
114 #ifdef EXPERIMENTAL_BRIGHTMAIL
115 US"bmi_optin",
116 #endif
117 US"condition",
118 US"continue",
119 US"control",
120 #ifdef WITH_CONTENT_SCAN
121 US"decode",
122 #endif
123 US"delay",
124 #ifdef WITH_OLD_DEMIME
125 US"demime",
126 #endif
127 #ifdef EXPERIMENTAL_DOMAINKEYS
128 US"dk_domain_source",
129 US"dk_policy",
130 US"dk_sender_domains",
131 US"dk_sender_local_parts",
132 US"dk_senders",
133 US"dk_status",
134 #endif
135 US"dnslists",
136 US"domains",
137 US"encrypted",
138 US"endpass",
139 US"hosts",
140 US"local_parts",
141 US"log_message",
142 US"log_reject_target",
143 US"logwrite",
144 #ifdef WITH_CONTENT_SCAN
145 US"malware",
146 #endif
147 US"message",
148 #ifdef WITH_CONTENT_SCAN
149 US"mime_regex",
150 #endif
151 US"ratelimit",
152 US"recipients",
153 #ifdef WITH_CONTENT_SCAN
154 US"regex",
155 #endif
156 US"sender_domains", US"senders", US"set",
157 #ifdef WITH_CONTENT_SCAN
158 US"spam",
159 #endif
160 #ifdef EXPERIMENTAL_SPF
161 US"spf",
162 #endif
163 US"verify" };
164
165
166 /* Return values from decode_control(); keep in step with the table of names
167 that follows! */
168
169 enum {
170 CONTROL_AUTH_UNADVERTISED,
171 #ifdef EXPERIMENTAL_BRIGHTMAIL
172 CONTROL_BMI_RUN,
173 #endif
174 #ifdef EXPERIMENTAL_DOMAINKEYS
175 CONTROL_DK_VERIFY,
176 #endif
177 CONTROL_ERROR,
178 CONTROL_CASEFUL_LOCAL_PART,
179 CONTROL_CASELOWER_LOCAL_PART,
180 CONTROL_ENFORCE_SYNC,
181 CONTROL_NO_ENFORCE_SYNC,
182 CONTROL_FREEZE,
183 CONTROL_QUEUE_ONLY,
184 CONTROL_SUBMISSION,
185 CONTROL_SUPPRESS_LOCAL_FIXUPS,
186 #ifdef WITH_CONTENT_SCAN
187 CONTROL_NO_MBOX_UNSPOOL,
188 #endif
189 CONTROL_FAKEDEFER,
190 CONTROL_FAKEREJECT,
191 CONTROL_NO_MULTILINE,
192 CONTROL_NO_PIPELINING,
193 CONTROL_NO_DELAY_FLUSH,
194 CONTROL_NO_CALLOUT_FLUSH
195 };
196
197 /* ACL control names; keep in step with the table above! This list is used for
198 turning ids into names. The actual list of recognized names is in the variable
199 control_def controls_list[] below. The fact that there are two lists is a mess
200 and should be tidied up. */
201
202 static uschar *controls[] = {
203 US"allow_auth_unadvertised",
204 #ifdef EXPERIMENTAL_BRIGHTMAIL
205 US"bmi_run",
206 #endif
207 #ifdef EXPERIMENTAL_DOMAINKEYS
208 US"dk_verify",
209 #endif
210 US"error",
211 US"caseful_local_part",
212 US"caselower_local_part",
213 US"enforce_sync",
214 US"no_enforce_sync",
215 US"freeze",
216 US"queue_only",
217 US"submission",
218 US"suppress_local_fixups",
219 #ifdef WITH_CONTENT_SCAN
220 US"no_mbox_unspool",
221 #endif
222 US"fakedefer",
223 US"fakereject",
224 US"no_multiline_responses",
225 US"no_pipelining",
226 US"no_delay_flush",
227 US"no_callout_flush"
228 };
229
230 /* Flags to indicate for which conditions/modifiers a string expansion is done
231 at the outer level. In the other cases, expansion already occurs in the
232 checking functions. */
233
234 static uschar cond_expand_at_top[] = {
235 TRUE, /* acl */
236 TRUE, /* add_header */
237 FALSE, /* authenticated */
238 #ifdef EXPERIMENTAL_BRIGHTMAIL
239 TRUE, /* bmi_optin */
240 #endif
241 TRUE, /* condition */
242 TRUE, /* continue */
243 TRUE, /* control */
244 #ifdef WITH_CONTENT_SCAN
245 TRUE, /* decode */
246 #endif
247 TRUE, /* delay */
248 #ifdef WITH_OLD_DEMIME
249 TRUE, /* demime */
250 #endif
251 #ifdef EXPERIMENTAL_DOMAINKEYS
252 TRUE, /* dk_domain_source */
253 TRUE, /* dk_policy */
254 TRUE, /* dk_sender_domains */
255 TRUE, /* dk_sender_local_parts */
256 TRUE, /* dk_senders */
257 TRUE, /* dk_status */
258 #endif
259 TRUE, /* dnslists */
260 FALSE, /* domains */
261 FALSE, /* encrypted */
262 TRUE, /* endpass */
263 FALSE, /* hosts */
264 FALSE, /* local_parts */
265 TRUE, /* log_message */
266 TRUE, /* log_reject_target */
267 TRUE, /* logwrite */
268 #ifdef WITH_CONTENT_SCAN
269 TRUE, /* malware */
270 #endif
271 TRUE, /* message */
272 #ifdef WITH_CONTENT_SCAN
273 TRUE, /* mime_regex */
274 #endif
275 TRUE, /* ratelimit */
276 FALSE, /* recipients */
277 #ifdef WITH_CONTENT_SCAN
278 TRUE, /* regex */
279 #endif
280 FALSE, /* sender_domains */
281 FALSE, /* senders */
282 TRUE, /* set */
283 #ifdef WITH_CONTENT_SCAN
284 TRUE, /* spam */
285 #endif
286 #ifdef EXPERIMENTAL_SPF
287 TRUE, /* spf */
288 #endif
289 TRUE /* verify */
290 };
291
292 /* Flags to identify the modifiers */
293
294 static uschar cond_modifiers[] = {
295 FALSE, /* acl */
296 TRUE, /* add_header */
297 FALSE, /* authenticated */
298 #ifdef EXPERIMENTAL_BRIGHTMAIL
299 TRUE, /* bmi_optin */
300 #endif
301 FALSE, /* condition */
302 TRUE, /* continue */
303 TRUE, /* control */
304 #ifdef WITH_CONTENT_SCAN
305 FALSE, /* decode */
306 #endif
307 TRUE, /* delay */
308 #ifdef WITH_OLD_DEMIME
309 FALSE, /* demime */
310 #endif
311 #ifdef EXPERIMENTAL_DOMAINKEYS
312 FALSE, /* dk_domain_source */
313 FALSE, /* dk_policy */
314 FALSE, /* dk_sender_domains */
315 FALSE, /* dk_sender_local_parts */
316 FALSE, /* dk_senders */
317 FALSE, /* dk_status */
318 #endif
319 FALSE, /* dnslists */
320 FALSE, /* domains */
321 FALSE, /* encrypted */
322 TRUE, /* endpass */
323 FALSE, /* hosts */
324 FALSE, /* local_parts */
325 TRUE, /* log_message */
326 TRUE, /* log_reject_target */
327 TRUE, /* logwrite */
328 #ifdef WITH_CONTENT_SCAN
329 FALSE, /* malware */
330 #endif
331 TRUE, /* message */
332 #ifdef WITH_CONTENT_SCAN
333 FALSE, /* mime_regex */
334 #endif
335 FALSE, /* ratelimit */
336 FALSE, /* recipients */
337 #ifdef WITH_CONTENT_SCAN
338 FALSE, /* regex */
339 #endif
340 FALSE, /* sender_domains */
341 FALSE, /* senders */
342 TRUE, /* set */
343 #ifdef WITH_CONTENT_SCAN
344 FALSE, /* spam */
345 #endif
346 #ifdef EXPERIMENTAL_SPF
347 FALSE, /* spf */
348 #endif
349 FALSE /* verify */
350 };
351
352 /* Bit map vector of which conditions and modifiers are not allowed at certain
353 times. For each condition, there's a bitmap of dis-allowed times. For some, it
354 is easier to specify the negation of a small number of allowed times. */
355
356 static unsigned int cond_forbids[] = {
357 0, /* acl */
358
359 (unsigned int)
360 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* add_header */
361 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
362 (1<<ACL_WHERE_MIME)|(1<<ACL_WHERE_NOTSMTP)|
363 (1<<ACL_WHERE_NOTSMTP_START)),
364
365 (1<<ACL_WHERE_NOTSMTP)| /* authenticated */
366 (1<<ACL_WHERE_NOTSMTP_START)|
367 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO),
368
369 #ifdef EXPERIMENTAL_BRIGHTMAIL
370 (1<<ACL_WHERE_AUTH)| /* bmi_optin */
371 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
372 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_MIME)|
373 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
374 (1<<ACL_WHERE_MAILAUTH)|
375 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
376 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_PREDATA)|
377 (1<<ACL_WHERE_NOTSMTP_START),
378 #endif
379
380 0, /* condition */
381
382 0, /* continue */
383
384 /* Certain types of control are always allowed, so we let it through
385 always and check in the control processing itself. */
386
387 0, /* control */
388
389 #ifdef WITH_CONTENT_SCAN
390 (unsigned int)
391 ~(1<<ACL_WHERE_MIME), /* decode */
392 #endif
393
394 0, /* delay */
395
396 #ifdef WITH_OLD_DEMIME
397 (unsigned int)
398 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)), /* demime */
399 #endif
400
401 #ifdef EXPERIMENTAL_DOMAINKEYS
402 (1<<ACL_WHERE_AUTH)| /* dk_domain_source */
403 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
404 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
405 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
406 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
407 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
408 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_NOTSMTP_START),
409
410 (1<<ACL_WHERE_AUTH)| /* dk_policy */
411 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
412 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
413 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
414 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
415 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
416 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_NOTSMTP_START),
417
418 (1<<ACL_WHERE_AUTH)| /* dk_sender_domains */
419 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
420 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
421 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
422 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
423 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
424 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_NOTSMTP_START),
425
426 (1<<ACL_WHERE_AUTH)| /* dk_sender_local_parts */
427 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
428 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
429 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
430 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
431 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
432 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_NOTSMTP_START),
433
434 (1<<ACL_WHERE_AUTH)| /* dk_senders */
435 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
436 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
437 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
438 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
439 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
440 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_NOTSMTP_START),
441
442 (1<<ACL_WHERE_AUTH)| /* dk_status */
443 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
444 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
445 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
446 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
447 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
448 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_NOTSMTP_START),
449 #endif
450
451 (1<<ACL_WHERE_NOTSMTP)| /* dnslists */
452 (1<<ACL_WHERE_NOTSMTP_START),
453
454 (unsigned int)
455 ~(1<<ACL_WHERE_RCPT), /* domains */
456
457 (1<<ACL_WHERE_NOTSMTP)| /* encrypted */
458 (1<<ACL_WHERE_CONNECT)|
459 (1<<ACL_WHERE_NOTSMTP_START)|
460 (1<<ACL_WHERE_HELO),
461
462 0, /* endpass */
463
464 (1<<ACL_WHERE_NOTSMTP)| /* hosts */
465 (1<<ACL_WHERE_NOTSMTP_START),
466
467 (unsigned int)
468 ~(1<<ACL_WHERE_RCPT), /* local_parts */
469
470 0, /* log_message */
471
472 0, /* log_reject_target */
473
474 0, /* logwrite */
475
476 #ifdef WITH_CONTENT_SCAN
477 (unsigned int)
478 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)), /* malware */
479 #endif
480
481 0, /* message */
482
483 #ifdef WITH_CONTENT_SCAN
484 (unsigned int)
485 ~(1<<ACL_WHERE_MIME), /* mime_regex */
486 #endif
487
488 0, /* ratelimit */
489
490 (unsigned int)
491 ~(1<<ACL_WHERE_RCPT), /* recipients */
492
493 #ifdef WITH_CONTENT_SCAN
494 (unsigned int)
495 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* regex */
496 (1<<ACL_WHERE_MIME)),
497 #endif
498
499 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* sender_domains */
500 (1<<ACL_WHERE_HELO)|
501 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
502 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
503 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
504
505 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* senders */
506 (1<<ACL_WHERE_HELO)|
507 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
508 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
509 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
510
511 0, /* set */
512
513 #ifdef WITH_CONTENT_SCAN
514 (unsigned int)
515 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)), /* spam */
516 #endif
517
518 #ifdef EXPERIMENTAL_SPF
519 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* spf */
520 (1<<ACL_WHERE_HELO)|
521 (1<<ACL_WHERE_MAILAUTH)|
522 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
523 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY)|
524 (1<<ACL_WHERE_NOTSMTP)|
525 (1<<ACL_WHERE_NOTSMTP_START),
526 #endif
527
528 /* Certain types of verify are always allowed, so we let it through
529 always and check in the verify function itself */
530
531 0 /* verify */
532 };
533
534
535 /* Bit map vector of which controls are not allowed at certain times. For
536 each control, there's a bitmap of dis-allowed times. For some, it is easier to
537 specify the negation of a small number of allowed times. */
538
539 static unsigned int control_forbids[] = {
540 (unsigned int)
541 ~((1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)), /* allow_auth_unadvertised */
542
543 #ifdef EXPERIMENTAL_BRIGHTMAIL
544 0, /* bmi_run */
545 #endif
546
547 #ifdef EXPERIMENTAL_DOMAINKEYS
548 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* dk_verify */
549 (1<<ACL_WHERE_NOTSMTP_START),
550 #endif
551
552 0, /* error */
553
554 (unsigned int)
555 ~(1<<ACL_WHERE_RCPT), /* caseful_local_part */
556
557 (unsigned int)
558 ~(1<<ACL_WHERE_RCPT), /* caselower_local_part */
559
560 (1<<ACL_WHERE_NOTSMTP)| /* enforce_sync */
561 (1<<ACL_WHERE_NOTSMTP_START),
562
563 (1<<ACL_WHERE_NOTSMTP)| /* no_enforce_sync */
564 (1<<ACL_WHERE_NOTSMTP_START),
565
566 (unsigned int)
567 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* freeze */
568 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
569 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)),
570
571 (unsigned int)
572 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* queue_only */
573 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
574 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)),
575
576 (unsigned int)
577 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* submission */
578 (1<<ACL_WHERE_PREDATA)),
579
580 (unsigned int)
581 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* suppress_local_fixups */
582 (1<<ACL_WHERE_PREDATA)|
583 (1<<ACL_WHERE_NOTSMTP_START)),
584
585 #ifdef WITH_CONTENT_SCAN
586 (unsigned int)
587 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* no_mbox_unspool */
588 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
589 (1<<ACL_WHERE_MIME)),
590 #endif
591
592 (unsigned int)
593 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakedefer */
594 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
595 (1<<ACL_WHERE_MIME)),
596
597 (unsigned int)
598 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakereject */
599 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
600 (1<<ACL_WHERE_MIME)),
601
602 (1<<ACL_WHERE_NOTSMTP)| /* no_multiline */
603 (1<<ACL_WHERE_NOTSMTP_START),
604
605 (1<<ACL_WHERE_NOTSMTP)| /* no_pipelining */
606 (1<<ACL_WHERE_NOTSMTP_START),
607
608 (1<<ACL_WHERE_NOTSMTP)| /* no_delay_flush */
609 (1<<ACL_WHERE_NOTSMTP_START),
610
611 (1<<ACL_WHERE_NOTSMTP)| /* no_callout_flush */
612 (1<<ACL_WHERE_NOTSMTP_START)
613 };
614
615 /* Structure listing various control arguments, with their characteristics. */
616
617 typedef struct control_def {
618 uschar *name;
619 int value; /* CONTROL_xxx value */
620 BOOL has_option; /* Has /option(s) following */
621 } control_def;
622
623 static control_def controls_list[] = {
624 { US"allow_auth_unadvertised", CONTROL_AUTH_UNADVERTISED, FALSE },
625 #ifdef EXPERIMENTAL_BRIGHTMAIL
626 { US"bmi_run", CONTROL_BMI_RUN, FALSE },
627 #endif
628 #ifdef EXPERIMENTAL_DOMAINKEYS
629 { US"dk_verify", CONTROL_DK_VERIFY, FALSE },
630 #endif
631 { US"caseful_local_part", CONTROL_CASEFUL_LOCAL_PART, FALSE },
632 { US"caselower_local_part", CONTROL_CASELOWER_LOCAL_PART, FALSE },
633 { US"enforce_sync", CONTROL_ENFORCE_SYNC, FALSE },
634 { US"freeze", CONTROL_FREEZE, TRUE },
635 { US"no_callout_flush", CONTROL_NO_CALLOUT_FLUSH, FALSE },
636 { US"no_delay_flush", CONTROL_NO_DELAY_FLUSH, FALSE },
637 { US"no_enforce_sync", CONTROL_NO_ENFORCE_SYNC, FALSE },
638 { US"no_multiline_responses", CONTROL_NO_MULTILINE, FALSE },
639 { US"no_pipelining", CONTROL_NO_PIPELINING, FALSE },
640 { US"queue_only", CONTROL_QUEUE_ONLY, FALSE },
641 #ifdef WITH_CONTENT_SCAN
642 { US"no_mbox_unspool", CONTROL_NO_MBOX_UNSPOOL, FALSE },
643 #endif
644 { US"fakedefer", CONTROL_FAKEDEFER, TRUE },
645 { US"fakereject", CONTROL_FAKEREJECT, TRUE },
646 { US"submission", CONTROL_SUBMISSION, TRUE },
647 { US"suppress_local_fixups", CONTROL_SUPPRESS_LOCAL_FIXUPS, FALSE }
648 };
649
650 /* Support data structures for Client SMTP Authorization. acl_verify_csa()
651 caches its result in a tree to avoid repeated DNS queries. The result is an
652 integer code which is used as an index into the following tables of
653 explanatory strings and verification return codes. */
654
655 static tree_node *csa_cache = NULL;
656
657 enum { CSA_UNKNOWN, CSA_OK, CSA_DEFER_SRV, CSA_DEFER_ADDR,
658 CSA_FAIL_EXPLICIT, CSA_FAIL_DOMAIN, CSA_FAIL_NOADDR, CSA_FAIL_MISMATCH };
659
660 /* The acl_verify_csa() return code is translated into an acl_verify() return
661 code using the following table. It is OK unless the client is definitely not
662 authorized. This is because CSA is supposed to be optional for sending sites,
663 so recipients should not be too strict about checking it - especially because
664 DNS problems are quite likely to occur. It's possible to use $csa_status in
665 further ACL conditions to distinguish ok, unknown, and defer if required, but
666 the aim is to make the usual configuration simple. */
667
668 static int csa_return_code[] = {
669 OK, OK, OK, OK,
670 FAIL, FAIL, FAIL, FAIL
671 };
672
673 static uschar *csa_status_string[] = {
674 US"unknown", US"ok", US"defer", US"defer",
675 US"fail", US"fail", US"fail", US"fail"
676 };
677
678 static uschar *csa_reason_string[] = {
679 US"unknown",
680 US"ok",
681 US"deferred (SRV lookup failed)",
682 US"deferred (target address lookup failed)",
683 US"failed (explicit authorization required)",
684 US"failed (host name not authorized)",
685 US"failed (no authorized addresses)",
686 US"failed (client address mismatch)"
687 };
688
689 /* Enable recursion between acl_check_internal() and acl_check_condition() */
690
691 static int acl_check_internal(int, address_item *, uschar *, int, uschar **,
692 uschar **);
693
694
695 /*************************************************
696 * Pick out name from list *
697 *************************************************/
698
699 /* Use a binary chop method
700
701 Arguments:
702 name name to find
703 list list of names
704 end size of list
705
706 Returns: offset in list, or -1 if not found
707 */
708
709 static int
710 acl_checkname(uschar *name, uschar **list, int end)
711 {
712 int start = 0;
713
714 while (start < end)
715 {
716 int mid = (start + end)/2;
717 int c = Ustrcmp(name, list[mid]);
718 if (c == 0) return mid;
719 if (c < 0) end = mid; else start = mid + 1;
720 }
721
722 return -1;
723 }
724
725
726 /*************************************************
727 * Read and parse one ACL *
728 *************************************************/
729
730 /* This function is called both from readconf in order to parse the ACLs in the
731 configuration file, and also when an ACL is encountered dynamically (e.g. as
732 the result of an expansion). It is given a function to call in order to
733 retrieve the lines of the ACL. This function handles skipping comments and
734 blank lines (where relevant).
735
736 Arguments:
737 func function to get next line of ACL
738 error where to put an error message
739
740 Returns: pointer to ACL, or NULL
741 NULL can be legal (empty ACL); in this case error will be NULL
742 */
743
744 acl_block *
745 acl_read(uschar *(*func)(void), uschar **error)
746 {
747 acl_block *yield = NULL;
748 acl_block **lastp = &yield;
749 acl_block *this = NULL;
750 acl_condition_block *cond;
751 acl_condition_block **condp = NULL;
752 uschar *s;
753
754 *error = NULL;
755
756 while ((s = (*func)()) != NULL)
757 {
758 int v, c;
759 BOOL negated = FALSE;
760 uschar *saveline = s;
761 uschar name[64];
762
763 /* Conditions (but not verbs) are allowed to be negated by an initial
764 exclamation mark. */
765
766 while (isspace(*s)) s++;
767 if (*s == '!')
768 {
769 negated = TRUE;
770 s++;
771 }
772
773 /* Read the name of a verb or a condition, or the start of a new ACL, which
774 can be started by a name, or by a macro definition. */
775
776 s = readconf_readname(name, sizeof(name), s);
777 if (*s == ':' || (isupper(name[0]) && *s == '=')) return yield;
778
779 /* If a verb is unrecognized, it may be another condition or modifier that
780 continues the previous verb. */
781
782 v = acl_checkname(name, verbs, sizeof(verbs)/sizeof(char *));
783 if (v < 0)
784 {
785 if (this == NULL)
786 {
787 *error = string_sprintf("unknown ACL verb \"%s\" in \"%s\"", name,
788 saveline);
789 return NULL;
790 }
791 }
792
793 /* New verb */
794
795 else
796 {
797 if (negated)
798 {
799 *error = string_sprintf("malformed ACL line \"%s\"", saveline);
800 return NULL;
801 }
802 this = store_get(sizeof(acl_block));
803 *lastp = this;
804 lastp = &(this->next);
805 this->next = NULL;
806 this->verb = v;
807 this->condition = NULL;
808 condp = &(this->condition);
809 if (*s == 0) continue; /* No condition on this line */
810 if (*s == '!')
811 {
812 negated = TRUE;
813 s++;
814 }
815 s = readconf_readname(name, sizeof(name), s); /* Condition name */
816 }
817
818 /* Handle a condition or modifier. */
819
820 c = acl_checkname(name, conditions, sizeof(conditions)/sizeof(char *));
821 if (c < 0)
822 {
823 *error = string_sprintf("unknown ACL condition/modifier in \"%s\"",
824 saveline);
825 return NULL;
826 }
827
828 /* The modifiers may not be negated */
829
830 if (negated && cond_modifiers[c])
831 {
832 *error = string_sprintf("ACL error: negation is not allowed with "
833 "\"%s\"", conditions[c]);
834 return NULL;
835 }
836
837 /* ENDPASS may occur only with ACCEPT or DISCARD. */
838
839 if (c == ACLC_ENDPASS &&
840 this->verb != ACL_ACCEPT &&
841 this->verb != ACL_DISCARD)
842 {
843 *error = string_sprintf("ACL error: \"%s\" is not allowed with \"%s\"",
844 conditions[c], verbs[this->verb]);
845 return NULL;
846 }
847
848 cond = store_get(sizeof(acl_condition_block));
849 cond->next = NULL;
850 cond->type = c;
851 cond->u.negated = negated;
852
853 *condp = cond;
854 condp = &(cond->next);
855
856 /* The "set" modifier is different in that its argument is "name=value"
857 rather than just a value, and we can check the validity of the name, which
858 gives us a variable name to insert into the data block. The original ACL
859 variable names were acl_c0 ... acl_c9 and acl_m0 ... acl_m9. This was
860 extended to 20 of each type, but after that people successfully argued for
861 arbitrary names. In the new scheme, the names must start with acl_c or acl_m.
862 After that, we allow alphanumerics and underscores, but the first character
863 after c or m must be a digit or an underscore. This retains backwards
864 compatibility. */
865
866 if (c == ACLC_SET)
867 {
868 uschar *endptr;
869
870 if (Ustrncmp(s, "acl_c", 5) != 0 &&
871 Ustrncmp(s, "acl_m", 5) != 0)
872 {
873 *error = string_sprintf("invalid variable name after \"set\" in ACL "
874 "modifier \"set %s\" (must start \"acl_c\" or \"acl_m\")", s);
875 return NULL;
876 }
877
878 endptr = s + 5;
879 if (!isdigit(*endptr) && *endptr != '_')
880 {
881 *error = string_sprintf("invalid variable name after \"set\" in ACL "
882 "modifier \"set %s\" (digit or underscore must follow acl_c or acl_m)",
883 s);
884 return NULL;
885 }
886
887 while (*endptr != 0 && *endptr != '=' && !isspace(*endptr))
888 {
889 if (!isalnum(*endptr) && *endptr != '_')
890 {
891 *error = string_sprintf("invalid character \"%c\" in variable name "
892 "in ACL modifier \"set %s\"", *endptr, s);
893 return NULL;
894 }
895 endptr++;
896 }
897
898 cond->u.varname = string_copyn(s + 4, endptr - s - 4);
899 s = endptr;
900 while (isspace(*s)) s++;
901 }
902
903 /* For "set", we are now positioned for the data. For the others, only
904 "endpass" has no data */
905
906 if (c != ACLC_ENDPASS)
907 {
908 if (*s++ != '=')
909 {
910 *error = string_sprintf("\"=\" missing after ACL \"%s\" %s", name,
911 cond_modifiers[c]? US"modifier" : US"condition");
912 return NULL;
913 }
914 while (isspace(*s)) s++;
915 cond->arg = string_copy(s);
916 }
917 }
918
919 return yield;
920 }
921
922
923
924 /*************************************************
925 * Set up added header line(s) *
926 *************************************************/
927
928 /* This function is called by the add_header modifier, and also from acl_warn()
929 to implement the now-deprecated way of adding header lines using "message" on a
930 "warn" verb. The argument is treated as a sequence of header lines which are
931 added to a chain, provided there isn't an identical one already there.
932
933 Argument: string of header lines
934 Returns: nothing
935 */
936
937 static void
938 setup_header(uschar *hstring)
939 {
940 uschar *p, *q;
941 int hlen = Ustrlen(hstring);
942
943 /* An empty string does nothing; otherwise add a final newline if necessary. */
944
945 if (hlen <= 0) return;
946 if (hstring[hlen-1] != '\n') hstring = string_sprintf("%s\n", hstring);
947
948 /* Loop for multiple header lines, taking care about continuations */
949
950 for (p = q = hstring; *p != 0; )
951 {
952 uschar *s;
953 int newtype = htype_add_bot;
954 header_line **hptr = &acl_added_headers;
955
956 /* Find next header line within the string */
957
958 for (;;)
959 {
960 q = Ustrchr(q, '\n');
961 if (*(++q) != ' ' && *q != '\t') break;
962 }
963
964 /* If the line starts with a colon, interpret the instruction for where to
965 add it. This temporarily sets up a new type. */
966
967 if (*p == ':')
968 {
969 if (strncmpic(p, US":after_received:", 16) == 0)
970 {
971 newtype = htype_add_rec;
972 p += 16;
973 }
974 else if (strncmpic(p, US":at_start_rfc:", 14) == 0)
975 {
976 newtype = htype_add_rfc;
977 p += 14;
978 }
979 else if (strncmpic(p, US":at_start:", 10) == 0)
980 {
981 newtype = htype_add_top;
982 p += 10;
983 }
984 else if (strncmpic(p, US":at_end:", 8) == 0)
985 {
986 newtype = htype_add_bot;
987 p += 8;
988 }
989 while (*p == ' ' || *p == '\t') p++;
990 }
991
992 /* See if this line starts with a header name, and if not, add X-ACL-Warn:
993 to the front of it. */
994
995 for (s = p; s < q - 1; s++)
996 {
997 if (*s == ':' || !isgraph(*s)) break;
998 }
999
1000 s = string_sprintf("%s%.*s", (*s == ':')? "" : "X-ACL-Warn: ", q - p, p);
1001 hlen = Ustrlen(s);
1002
1003 /* See if this line has already been added */
1004
1005 while (*hptr != NULL)
1006 {
1007 if (Ustrncmp((*hptr)->text, s, hlen) == 0) break;
1008 hptr = &((*hptr)->next);
1009 }
1010
1011 /* Add if not previously present */
1012
1013 if (*hptr == NULL)
1014 {
1015 header_line *h = store_get(sizeof(header_line));
1016 h->text = s;
1017 h->next = NULL;
1018 h->type = newtype;
1019 h->slen = hlen;
1020 *hptr = h;
1021 hptr = &(h->next);
1022 }
1023
1024 /* Advance for next header line within the string */
1025
1026 p = q;
1027 }
1028 }
1029
1030
1031
1032
1033 /*************************************************
1034 * Handle warnings *
1035 *************************************************/
1036
1037 /* This function is called when a WARN verb's conditions are true. It adds to
1038 the message's headers, and/or writes information to the log. In each case, this
1039 only happens once (per message for headers, per connection for log).
1040
1041 ** NOTE: The header adding action using the "message" setting is historic, and
1042 its use is now deprecated. The new add_header modifier should be used instead.
1043
1044 Arguments:
1045 where ACL_WHERE_xxxx indicating which ACL this is
1046 user_message message for adding to headers
1047 log_message message for logging, if different
1048
1049 Returns: nothing
1050 */
1051
1052 static void
1053 acl_warn(int where, uschar *user_message, uschar *log_message)
1054 {
1055 if (log_message != NULL && log_message != user_message)
1056 {
1057 uschar *text;
1058 string_item *logged;
1059
1060 text = string_sprintf("%s Warning: %s", host_and_ident(TRUE),
1061 string_printing(log_message));
1062
1063 /* If a sender verification has failed, and the log message is "sender verify
1064 failed", add the failure message. */
1065
1066 if (sender_verified_failed != NULL &&
1067 sender_verified_failed->message != NULL &&
1068 strcmpic(log_message, US"sender verify failed") == 0)
1069 text = string_sprintf("%s: %s", text, sender_verified_failed->message);
1070
1071 /* Search previously logged warnings. They are kept in malloc
1072 store so they can be freed at the start of a new message. */
1073
1074 for (logged = acl_warn_logged; logged != NULL; logged = logged->next)
1075 if (Ustrcmp(logged->text, text) == 0) break;
1076
1077 if (logged == NULL)
1078 {
1079 int length = Ustrlen(text) + 1;
1080 log_write(0, LOG_MAIN, "%s", text);
1081 logged = store_malloc(sizeof(string_item) + length);
1082 logged->text = (uschar *)logged + sizeof(string_item);
1083 memcpy(logged->text, text, length);
1084 logged->next = acl_warn_logged;
1085 acl_warn_logged = logged;
1086 }
1087 }
1088
1089 /* If there's no user message, we are done. */
1090
1091 if (user_message == NULL) return;
1092
1093 /* If this isn't a message ACL, we can't do anything with a user message.
1094 Log an error. */
1095
1096 if (where > ACL_WHERE_NOTSMTP)
1097 {
1098 log_write(0, LOG_MAIN|LOG_PANIC, "ACL \"warn\" with \"message\" setting "
1099 "found in a non-message (%s) ACL: cannot specify header lines here: "
1100 "message ignored", acl_wherenames[where]);
1101 return;
1102 }
1103
1104 /* The code for setting up header lines is now abstracted into a separate
1105 function so that it can be used for the add_header modifier as well. */
1106
1107 setup_header(user_message);
1108 }
1109
1110
1111
1112 /*************************************************
1113 * Verify and check reverse DNS *
1114 *************************************************/
1115
1116 /* Called from acl_verify() below. We look up the host name(s) of the client IP
1117 address if this has not yet been done. The host_name_lookup() function checks
1118 that one of these names resolves to an address list that contains the client IP
1119 address, so we don't actually have to do the check here.
1120
1121 Arguments:
1122 user_msgptr pointer for user message
1123 log_msgptr pointer for log message
1124
1125 Returns: OK verification condition succeeded
1126 FAIL verification failed
1127 DEFER there was a problem verifying
1128 */
1129
1130 static int
1131 acl_verify_reverse(uschar **user_msgptr, uschar **log_msgptr)
1132 {
1133 int rc;
1134
1135 user_msgptr = user_msgptr; /* stop compiler warning */
1136
1137 /* Previous success */
1138
1139 if (sender_host_name != NULL) return OK;
1140
1141 /* Previous failure */
1142
1143 if (host_lookup_failed)
1144 {
1145 *log_msgptr = string_sprintf("host lookup failed%s", host_lookup_msg);
1146 return FAIL;
1147 }
1148
1149 /* Need to do a lookup */
1150
1151 HDEBUG(D_acl)
1152 debug_printf("looking up host name to force name/address consistency check\n");
1153
1154 if ((rc = host_name_lookup()) != OK)
1155 {
1156 *log_msgptr = (rc == DEFER)?
1157 US"host lookup deferred for reverse lookup check"
1158 :
1159 string_sprintf("host lookup failed for reverse lookup check%s",
1160 host_lookup_msg);
1161 return rc; /* DEFER or FAIL */
1162 }
1163
1164 host_build_sender_fullhost();
1165 return OK;
1166 }
1167
1168
1169
1170 /*************************************************
1171 * Check client IP address matches CSA target *
1172 *************************************************/
1173
1174 /* Called from acl_verify_csa() below. This routine scans a section of a DNS
1175 response for address records belonging to the CSA target hostname. The section
1176 is specified by the reset argument, either RESET_ADDITIONAL or RESET_ANSWERS.
1177 If one of the addresses matches the client's IP address, then the client is
1178 authorized by CSA. If there are target IP addresses but none of them match
1179 then the client is using an unauthorized IP address. If there are no target IP
1180 addresses then the client cannot be using an authorized IP address. (This is
1181 an odd configuration - why didn't the SRV record have a weight of 1 instead?)
1182
1183 Arguments:
1184 dnsa the DNS answer block
1185 dnss a DNS scan block for us to use
1186 reset option specifing what portion to scan, as described above
1187 target the target hostname to use for matching RR names
1188
1189 Returns: CSA_OK successfully authorized
1190 CSA_FAIL_MISMATCH addresses found but none matched
1191 CSA_FAIL_NOADDR no target addresses found
1192 */
1193
1194 static int
1195 acl_verify_csa_address(dns_answer *dnsa, dns_scan *dnss, int reset,
1196 uschar *target)
1197 {
1198 dns_record *rr;
1199 dns_address *da;
1200
1201 BOOL target_found = FALSE;
1202
1203 for (rr = dns_next_rr(dnsa, dnss, reset);
1204 rr != NULL;
1205 rr = dns_next_rr(dnsa, dnss, RESET_NEXT))
1206 {
1207 /* Check this is an address RR for the target hostname. */
1208
1209 if (rr->type != T_A
1210 #if HAVE_IPV6
1211 && rr->type != T_AAAA
1212 #ifdef SUPPORT_A6
1213 && rr->type != T_A6
1214 #endif
1215 #endif
1216 ) continue;
1217
1218 if (strcmpic(target, rr->name) != 0) continue;
1219
1220 target_found = TRUE;
1221
1222 /* Turn the target address RR into a list of textual IP addresses and scan
1223 the list. There may be more than one if it is an A6 RR. */
1224
1225 for (da = dns_address_from_rr(dnsa, rr); da != NULL; da = da->next)
1226 {
1227 /* If the client IP address matches the target IP address, it's good! */
1228
1229 DEBUG(D_acl) debug_printf("CSA target address is %s\n", da->address);
1230
1231 if (strcmpic(sender_host_address, da->address) == 0) return CSA_OK;
1232 }
1233 }
1234
1235 /* If we found some target addresses but none of them matched, the client is
1236 using an unauthorized IP address, otherwise the target has no authorized IP
1237 addresses. */
1238
1239 if (target_found) return CSA_FAIL_MISMATCH;
1240 else return CSA_FAIL_NOADDR;
1241 }
1242
1243
1244
1245 /*************************************************
1246 * Verify Client SMTP Authorization *
1247 *************************************************/
1248
1249 /* Called from acl_verify() below. This routine calls dns_lookup_special()
1250 to find the CSA SRV record corresponding to the domain argument, or
1251 $sender_helo_name if no argument is provided. It then checks that the
1252 client is authorized, and that its IP address corresponds to the SRV
1253 target's address by calling acl_verify_csa_address() above. The address
1254 should have been returned in the DNS response's ADDITIONAL section, but if
1255 not we perform another DNS lookup to get it.
1256
1257 Arguments:
1258 domain pointer to optional parameter following verify = csa
1259
1260 Returns: CSA_UNKNOWN no valid CSA record found
1261 CSA_OK successfully authorized
1262 CSA_FAIL_* client is definitely not authorized
1263 CSA_DEFER_* there was a DNS problem
1264 */
1265
1266 static int
1267 acl_verify_csa(uschar *domain)
1268 {
1269 tree_node *t;
1270 uschar *found, *p;
1271 int priority, weight, port;
1272 dns_answer dnsa;
1273 dns_scan dnss;
1274 dns_record *rr;
1275 int rc, type;
1276 uschar target[256];
1277
1278 /* Work out the domain we are using for the CSA lookup. The default is the
1279 client's HELO domain. If the client has not said HELO, use its IP address
1280 instead. If it's a local client (exim -bs), CSA isn't applicable. */
1281
1282 while (isspace(*domain) && *domain != '\0') ++domain;
1283 if (*domain == '\0') domain = sender_helo_name;
1284 if (domain == NULL) domain = sender_host_address;
1285 if (sender_host_address == NULL) return CSA_UNKNOWN;
1286
1287 /* If we have an address literal, strip off the framing ready for turning it
1288 into a domain. The framing consists of matched square brackets possibly
1289 containing a keyword and a colon before the actual IP address. */
1290
1291 if (domain[0] == '[')
1292 {
1293 uschar *start = Ustrchr(domain, ':');
1294 if (start == NULL) start = domain;
1295 domain = string_copyn(start + 1, Ustrlen(start) - 2);
1296 }
1297
1298 /* Turn domains that look like bare IP addresses into domains in the reverse
1299 DNS. This code also deals with address literals and $sender_host_address. It's
1300 not quite kosher to treat bare domains such as EHLO 192.0.2.57 the same as
1301 address literals, but it's probably the most friendly thing to do. This is an
1302 extension to CSA, so we allow it to be turned off for proper conformance. */
1303
1304 if (string_is_ip_address(domain, NULL) != 0)
1305 {
1306 if (!dns_csa_use_reverse) return CSA_UNKNOWN;
1307 dns_build_reverse(domain, target);
1308 domain = target;
1309 }
1310
1311 /* Find out if we've already done the CSA check for this domain. If we have,
1312 return the same result again. Otherwise build a new cached result structure
1313 for this domain. The name is filled in now, and the value is filled in when
1314 we return from this function. */
1315
1316 t = tree_search(csa_cache, domain);
1317 if (t != NULL) return t->data.val;
1318
1319 t = store_get_perm(sizeof(tree_node) + Ustrlen(domain));
1320 Ustrcpy(t->name, domain);
1321 (void)tree_insertnode(&csa_cache, t);
1322
1323 /* Now we are ready to do the actual DNS lookup(s). */
1324
1325 found = domain;
1326 switch (dns_special_lookup(&dnsa, domain, T_CSA, &found))
1327 {
1328 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1329
1330 default:
1331 return t->data.val = CSA_DEFER_SRV;
1332
1333 /* If we found nothing, the client's authorization is unknown. */
1334
1335 case DNS_NOMATCH:
1336 case DNS_NODATA:
1337 return t->data.val = CSA_UNKNOWN;
1338
1339 /* We got something! Go on to look at the reply in more detail. */
1340
1341 case DNS_SUCCEED:
1342 break;
1343 }
1344
1345 /* Scan the reply for well-formed CSA SRV records. */
1346
1347 for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS);
1348 rr != NULL;
1349 rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT))
1350 {
1351 if (rr->type != T_SRV) continue;
1352
1353 /* Extract the numerical SRV fields (p is incremented) */
1354
1355 p = rr->data;
1356 GETSHORT(priority, p);
1357 GETSHORT(weight, p);
1358 GETSHORT(port, p);
1359
1360 DEBUG(D_acl)
1361 debug_printf("CSA priority=%d weight=%d port=%d\n", priority, weight, port);
1362
1363 /* Check the CSA version number */
1364
1365 if (priority != 1) continue;
1366
1367 /* If the domain does not have a CSA SRV record of its own (i.e. the domain
1368 found by dns_special_lookup() is a parent of the one we asked for), we check
1369 the subdomain assertions in the port field. At the moment there's only one
1370 assertion: legitimate SMTP clients are all explicitly authorized with CSA
1371 SRV records of their own. */
1372
1373 if (found != domain)
1374 {
1375 if (port & 1)
1376 return t->data.val = CSA_FAIL_EXPLICIT;
1377 else
1378 return t->data.val = CSA_UNKNOWN;
1379 }
1380
1381 /* This CSA SRV record refers directly to our domain, so we check the value
1382 in the weight field to work out the domain's authorization. 0 and 1 are
1383 unauthorized; 3 means the client is authorized but we can't check the IP
1384 address in order to authenticate it, so we treat it as unknown; values
1385 greater than 3 are undefined. */
1386
1387 if (weight < 2) return t->data.val = CSA_FAIL_DOMAIN;
1388
1389 if (weight > 2) continue;
1390
1391 /* Weight == 2, which means the domain is authorized. We must check that the
1392 client's IP address is listed as one of the SRV target addresses. Save the
1393 target hostname then break to scan the additional data for its addresses. */
1394
1395 (void)dn_expand(dnsa.answer, dnsa.answer + dnsa.answerlen, p,
1396 (DN_EXPAND_ARG4_TYPE)target, sizeof(target));
1397
1398 DEBUG(D_acl) debug_printf("CSA target is %s\n", target);
1399
1400 break;
1401 }
1402
1403 /* If we didn't break the loop then no appropriate records were found. */
1404
1405 if (rr == NULL) return t->data.val = CSA_UNKNOWN;
1406
1407 /* Do not check addresses if the target is ".", in accordance with RFC 2782.
1408 A target of "." indicates there are no valid addresses, so the client cannot
1409 be authorized. (This is an odd configuration because weight=2 target=. is
1410 equivalent to weight=1, but we check for it in order to keep load off the
1411 root name servers.) Note that dn_expand() turns "." into "". */
1412
1413 if (Ustrcmp(target, "") == 0) return t->data.val = CSA_FAIL_NOADDR;
1414
1415 /* Scan the additional section of the CSA SRV reply for addresses belonging
1416 to the target. If the name server didn't return any additional data (e.g.
1417 because it does not fully support SRV records), we need to do another lookup
1418 to obtain the target addresses; otherwise we have a definitive result. */
1419
1420 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ADDITIONAL, target);
1421 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1422
1423 /* The DNS lookup type corresponds to the IP version used by the client. */
1424
1425 #if HAVE_IPV6
1426 if (Ustrchr(sender_host_address, ':') != NULL)
1427 type = T_AAAA;
1428 else
1429 #endif /* HAVE_IPV6 */
1430 type = T_A;
1431
1432
1433 #if HAVE_IPV6 && defined(SUPPORT_A6)
1434 DNS_LOOKUP_AGAIN:
1435 #endif
1436
1437 switch (dns_lookup(&dnsa, target, type, NULL))
1438 {
1439 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1440
1441 default:
1442 return t->data.val = CSA_DEFER_ADDR;
1443
1444 /* If the query succeeded, scan the addresses and return the result. */
1445
1446 case DNS_SUCCEED:
1447 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ANSWERS, target);
1448 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1449 /* else fall through */
1450
1451 /* If the target has no IP addresses, the client cannot have an authorized
1452 IP address. However, if the target site uses A6 records (not AAAA records)
1453 we have to do yet another lookup in order to check them. */
1454
1455 case DNS_NOMATCH:
1456 case DNS_NODATA:
1457
1458 #if HAVE_IPV6 && defined(SUPPORT_A6)
1459 if (type == T_AAAA) { type = T_A6; goto DNS_LOOKUP_AGAIN; }
1460 #endif
1461
1462 return t->data.val = CSA_FAIL_NOADDR;
1463 }
1464 }
1465
1466
1467
1468 /*************************************************
1469 * Handle verification (address & other) *
1470 *************************************************/
1471
1472 /* This function implements the "verify" condition. It is called when
1473 encountered in any ACL, because some tests are almost always permitted. Some
1474 just don't make sense, and always fail (for example, an attempt to test a host
1475 lookup for a non-TCP/IP message). Others are restricted to certain ACLs.
1476
1477 Arguments:
1478 where where called from
1479 addr the recipient address that the ACL is handling, or NULL
1480 arg the argument of "verify"
1481 user_msgptr pointer for user message
1482 log_msgptr pointer for log message
1483 basic_errno where to put verify errno
1484
1485 Returns: OK verification condition succeeded
1486 FAIL verification failed
1487 DEFER there was a problem verifying
1488 ERROR syntax error
1489 */
1490
1491 static int
1492 acl_verify(int where, address_item *addr, uschar *arg,
1493 uschar **user_msgptr, uschar **log_msgptr, int *basic_errno)
1494 {
1495 int sep = '/';
1496 int callout = -1;
1497 int callout_overall = -1;
1498 int callout_connect = -1;
1499 int verify_options = 0;
1500 int rc;
1501 BOOL verify_header_sender = FALSE;
1502 BOOL defer_ok = FALSE;
1503 BOOL callout_defer_ok = FALSE;
1504 BOOL no_details = FALSE;
1505 BOOL success_on_redirect = FALSE;
1506 address_item *sender_vaddr = NULL;
1507 uschar *verify_sender_address = NULL;
1508 uschar *pm_mailfrom = NULL;
1509 uschar *se_mailfrom = NULL;
1510
1511 /* Some of the verify items have slash-separated options; some do not. Diagnose
1512 an error if options are given for items that don't expect them. This code has
1513 now got very message. Refactoring to use a table would be a good idea one day.
1514 */
1515
1516 uschar *slash = Ustrchr(arg, '/');
1517 uschar *list = arg;
1518 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
1519
1520 if (ss == NULL) goto BAD_VERIFY;
1521
1522 /* Handle name/address consistency verification in a separate function. */
1523
1524 if (strcmpic(ss, US"reverse_host_lookup") == 0)
1525 {
1526 if (slash != NULL) goto NO_OPTIONS;
1527 if (sender_host_address == NULL) return OK;
1528 return acl_verify_reverse(user_msgptr, log_msgptr);
1529 }
1530
1531 /* TLS certificate verification is done at STARTTLS time; here we just
1532 test whether it was successful or not. (This is for optional verification; for
1533 mandatory verification, the connection doesn't last this long.) */
1534
1535 if (strcmpic(ss, US"certificate") == 0)
1536 {
1537 if (slash != NULL) goto NO_OPTIONS;
1538 if (tls_certificate_verified) return OK;
1539 *user_msgptr = US"no verified certificate";
1540 return FAIL;
1541 }
1542
1543 /* We can test the result of optional HELO verification that might have
1544 occurred earlier. If not, we can attempt the verification now. */
1545
1546 if (strcmpic(ss, US"helo") == 0)
1547 {
1548 if (slash != NULL) goto NO_OPTIONS;
1549 if (!helo_verified && !helo_verify_failed) smtp_verify_helo();
1550 return helo_verified? OK : FAIL;
1551 }
1552
1553 /* Do Client SMTP Authorization checks in a separate function, and turn the
1554 result code into user-friendly strings. */
1555
1556 if (strcmpic(ss, US"csa") == 0)
1557 {
1558 rc = acl_verify_csa(list);
1559 *log_msgptr = *user_msgptr = string_sprintf("client SMTP authorization %s",
1560 csa_reason_string[rc]);
1561 csa_status = csa_status_string[rc];
1562 DEBUG(D_acl) debug_printf("CSA result %s\n", csa_status);
1563 return csa_return_code[rc];
1564 }
1565
1566 /* Check that all relevant header lines have the correct syntax. If there is
1567 a syntax error, we return details of the error to the sender if configured to
1568 send out full details. (But a "message" setting on the ACL can override, as
1569 always). */
1570
1571 if (strcmpic(ss, US"header_syntax") == 0)
1572 {
1573 if (slash != NULL) goto NO_OPTIONS;
1574 if (where != ACL_WHERE_DATA && where != ACL_WHERE_NOTSMTP) goto WRONG_ACL;
1575 rc = verify_check_headers(log_msgptr);
1576 if (rc != OK && smtp_return_error_details && *log_msgptr != NULL)
1577 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1578 return rc;
1579 }
1580
1581 /* Check that no recipient of this message is "blind", that is, every envelope
1582 recipient must be mentioned in either To: or Cc:. */
1583
1584 if (strcmpic(ss, US"not_blind") == 0)
1585 {
1586 if (slash != NULL) goto NO_OPTIONS;
1587 if (where != ACL_WHERE_DATA && where != ACL_WHERE_NOTSMTP) goto WRONG_ACL;
1588 rc = verify_check_notblind();
1589 if (rc != OK)
1590 {
1591 *log_msgptr = string_sprintf("bcc recipient detected");
1592 if (smtp_return_error_details)
1593 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1594 }
1595 return rc;
1596 }
1597
1598 /* The remaining verification tests check recipient and sender addresses,
1599 either from the envelope or from the header. There are a number of
1600 slash-separated options that are common to all of them. */
1601
1602
1603 /* Check that there is at least one verifiable sender address in the relevant
1604 header lines. This can be followed by callout and defer options, just like
1605 sender and recipient. */
1606
1607 if (strcmpic(ss, US"header_sender") == 0)
1608 {
1609 if (where != ACL_WHERE_DATA && where != ACL_WHERE_NOTSMTP) goto WRONG_ACL;
1610 verify_header_sender = TRUE;
1611 }
1612
1613 /* Otherwise, first item in verify argument must be "sender" or "recipient".
1614 In the case of a sender, this can optionally be followed by an address to use
1615 in place of the actual sender (rare special-case requirement). */
1616
1617 else if (strncmpic(ss, US"sender", 6) == 0)
1618 {
1619 uschar *s = ss + 6;
1620 if (where > ACL_WHERE_NOTSMTP)
1621 {
1622 *log_msgptr = string_sprintf("cannot verify sender in ACL for %s "
1623 "(only possible for MAIL, RCPT, PREDATA, or DATA)",
1624 acl_wherenames[where]);
1625 return ERROR;
1626 }
1627 if (*s == 0)
1628 verify_sender_address = sender_address;
1629 else
1630 {
1631 while (isspace(*s)) s++;
1632 if (*s++ != '=') goto BAD_VERIFY;
1633 while (isspace(*s)) s++;
1634 verify_sender_address = string_copy(s);
1635 }
1636 }
1637 else
1638 {
1639 if (strcmpic(ss, US"recipient") != 0) goto BAD_VERIFY;
1640 if (addr == NULL)
1641 {
1642 *log_msgptr = string_sprintf("cannot verify recipient in ACL for %s "
1643 "(only possible for RCPT)", acl_wherenames[where]);
1644 return ERROR;
1645 }
1646 }
1647
1648 /* Remaining items are optional; they apply to sender and recipient
1649 verification, including "header sender" verification. */
1650
1651 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size))
1652 != NULL)
1653 {
1654 if (strcmpic(ss, US"defer_ok") == 0) defer_ok = TRUE;
1655 else if (strcmpic(ss, US"no_details") == 0) no_details = TRUE;
1656 else if (strcmpic(ss, US"success_on_redirect") == 0) success_on_redirect = TRUE;
1657
1658 /* These two old options are left for backwards compatibility */
1659
1660 else if (strcmpic(ss, US"callout_defer_ok") == 0)
1661 {
1662 callout_defer_ok = TRUE;
1663 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1664 }
1665
1666 else if (strcmpic(ss, US"check_postmaster") == 0)
1667 {
1668 pm_mailfrom = US"";
1669 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1670 }
1671
1672 /* The callout option has a number of sub-options, comma separated */
1673
1674 else if (strncmpic(ss, US"callout", 7) == 0)
1675 {
1676 callout = CALLOUT_TIMEOUT_DEFAULT;
1677 ss += 7;
1678 if (*ss != 0)
1679 {
1680 while (isspace(*ss)) ss++;
1681 if (*ss++ == '=')
1682 {
1683 int optsep = ',';
1684 uschar *opt;
1685 uschar buffer[256];
1686 while (isspace(*ss)) ss++;
1687
1688 /* This callout option handling code has become a mess as new options
1689 have been added in an ad hoc manner. It should be tidied up into some
1690 kind of table-driven thing. */
1691
1692 while ((opt = string_nextinlist(&ss, &optsep, buffer, sizeof(buffer)))
1693 != NULL)
1694 {
1695 if (strcmpic(opt, US"defer_ok") == 0) callout_defer_ok = TRUE;
1696 else if (strcmpic(opt, US"no_cache") == 0)
1697 verify_options |= vopt_callout_no_cache;
1698 else if (strcmpic(opt, US"random") == 0)
1699 verify_options |= vopt_callout_random;
1700 else if (strcmpic(opt, US"use_sender") == 0)
1701 verify_options |= vopt_callout_recipsender;
1702 else if (strcmpic(opt, US"use_postmaster") == 0)
1703 verify_options |= vopt_callout_recippmaster;
1704 else if (strcmpic(opt, US"postmaster") == 0) pm_mailfrom = US"";
1705 else if (strcmpic(opt, US"fullpostmaster") == 0)
1706 {
1707 pm_mailfrom = US"";
1708 verify_options |= vopt_callout_fullpm;
1709 }
1710
1711 else if (strncmpic(opt, US"mailfrom", 8) == 0)
1712 {
1713 if (!verify_header_sender)
1714 {
1715 *log_msgptr = string_sprintf("\"mailfrom\" is allowed as a "
1716 "callout option only for verify=header_sender (detected in ACL "
1717 "condition \"%s\")", arg);
1718 return ERROR;
1719 }
1720 opt += 8;
1721 while (isspace(*opt)) opt++;
1722 if (*opt++ != '=')
1723 {
1724 *log_msgptr = string_sprintf("'=' expected after "
1725 "\"mailfrom\" in ACL condition \"%s\"", arg);
1726 return ERROR;
1727 }
1728 while (isspace(*opt)) opt++;
1729 se_mailfrom = string_copy(opt);
1730 }
1731
1732 else if (strncmpic(opt, US"postmaster_mailfrom", 19) == 0)
1733 {
1734 opt += 19;
1735 while (isspace(*opt)) opt++;
1736 if (*opt++ != '=')
1737 {
1738 *log_msgptr = string_sprintf("'=' expected after "
1739 "\"postmaster_mailfrom\" in ACL condition \"%s\"", arg);
1740 return ERROR;
1741 }
1742 while (isspace(*opt)) opt++;
1743 pm_mailfrom = string_copy(opt);
1744 }
1745
1746 else if (strncmpic(opt, US"maxwait", 7) == 0)
1747 {
1748 opt += 7;
1749 while (isspace(*opt)) opt++;
1750 if (*opt++ != '=')
1751 {
1752 *log_msgptr = string_sprintf("'=' expected after \"maxwait\" in "
1753 "ACL condition \"%s\"", arg);
1754 return ERROR;
1755 }
1756 while (isspace(*opt)) opt++;
1757 callout_overall = readconf_readtime(opt, 0, FALSE);
1758 if (callout_overall < 0)
1759 {
1760 *log_msgptr = string_sprintf("bad time value in ACL condition "
1761 "\"verify %s\"", arg);
1762 return ERROR;
1763 }
1764 }
1765 else if (strncmpic(opt, US"connect", 7) == 0)
1766 {
1767 opt += 7;
1768 while (isspace(*opt)) opt++;
1769 if (*opt++ != '=')
1770 {
1771 *log_msgptr = string_sprintf("'=' expected after "
1772 "\"callout_overaall\" in ACL condition \"%s\"", arg);
1773 return ERROR;
1774 }
1775 while (isspace(*opt)) opt++;
1776 callout_connect = readconf_readtime(opt, 0, FALSE);
1777 if (callout_connect < 0)
1778 {
1779 *log_msgptr = string_sprintf("bad time value in ACL condition "
1780 "\"verify %s\"", arg);
1781 return ERROR;
1782 }
1783 }
1784 else /* Plain time is callout connect/command timeout */
1785 {
1786 callout = readconf_readtime(opt, 0, FALSE);
1787 if (callout < 0)
1788 {
1789 *log_msgptr = string_sprintf("bad time value in ACL condition "
1790 "\"verify %s\"", arg);
1791 return ERROR;
1792 }
1793 }
1794 }
1795 }
1796 else
1797 {
1798 *log_msgptr = string_sprintf("'=' expected after \"callout\" in "
1799 "ACL condition \"%s\"", arg);
1800 return ERROR;
1801 }
1802 }
1803 }
1804
1805 /* Option not recognized */
1806
1807 else
1808 {
1809 *log_msgptr = string_sprintf("unknown option \"%s\" in ACL "
1810 "condition \"verify %s\"", ss, arg);
1811 return ERROR;
1812 }
1813 }
1814
1815 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster)) ==
1816 (vopt_callout_recipsender|vopt_callout_recippmaster))
1817 {
1818 *log_msgptr = US"only one of use_sender and use_postmaster can be set "
1819 "for a recipient callout";
1820 return ERROR;
1821 }
1822
1823 /* Handle sender-in-header verification. Default the user message to the log
1824 message if giving out verification details. */
1825
1826 if (verify_header_sender)
1827 {
1828 int verrno;
1829 rc = verify_check_header_address(user_msgptr, log_msgptr, callout,
1830 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, verify_options,
1831 &verrno);
1832 if (rc != OK)
1833 {
1834 *basic_errno = verrno;
1835 if (smtp_return_error_details)
1836 {
1837 if (*user_msgptr == NULL && *log_msgptr != NULL)
1838 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1839 if (rc == DEFER) acl_temp_details = TRUE;
1840 }
1841 }
1842 }
1843
1844 /* Handle a sender address. The default is to verify *the* sender address, but
1845 optionally a different address can be given, for special requirements. If the
1846 address is empty, we are dealing with a bounce message that has no sender, so
1847 we cannot do any checking. If the real sender address gets rewritten during
1848 verification (e.g. DNS widening), set the flag to stop it being rewritten again
1849 during message reception.
1850
1851 A list of verified "sender" addresses is kept to try to avoid doing to much
1852 work repetitively when there are multiple recipients in a message and they all
1853 require sender verification. However, when callouts are involved, it gets too
1854 complicated because different recipients may require different callout options.
1855 Therefore, we always do a full sender verify when any kind of callout is
1856 specified. Caching elsewhere, for instance in the DNS resolver and in the
1857 callout handling, should ensure that this is not terribly inefficient. */
1858
1859 else if (verify_sender_address != NULL)
1860 {
1861 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster))
1862 != 0)
1863 {
1864 *log_msgptr = US"use_sender or use_postmaster cannot be used for a "
1865 "sender verify callout";
1866 return ERROR;
1867 }
1868
1869 sender_vaddr = verify_checked_sender(verify_sender_address);
1870 if (sender_vaddr != NULL && /* Previously checked */
1871 callout <= 0) /* No callout needed this time */
1872 {
1873 /* If the "routed" flag is set, it means that routing worked before, so
1874 this check can give OK (the saved return code value, if set, belongs to a
1875 callout that was done previously). If the "routed" flag is not set, routing
1876 must have failed, so we use the saved return code. */
1877
1878 if (testflag(sender_vaddr, af_verify_routed)) rc = OK; else
1879 {
1880 rc = sender_vaddr->special_action;
1881 *basic_errno = sender_vaddr->basic_errno;
1882 }
1883 HDEBUG(D_acl) debug_printf("using cached sender verify result\n");
1884 }
1885
1886 /* Do a new verification, and cache the result. The cache is used to avoid
1887 verifying the sender multiple times for multiple RCPTs when callouts are not
1888 specified (see comments above).
1889
1890 The cache is also used on failure to give details in response to the first
1891 RCPT that gets bounced for this reason. However, this can be suppressed by
1892 the no_details option, which sets the flag that says "this detail has already
1893 been sent". The cache normally contains just one address, but there may be
1894 more in esoteric circumstances. */
1895
1896 else
1897 {
1898 BOOL routed = TRUE;
1899 uschar *save_address_data = deliver_address_data;
1900
1901 sender_vaddr = deliver_make_addr(verify_sender_address, TRUE);
1902 if (no_details) setflag(sender_vaddr, af_sverify_told);
1903 if (verify_sender_address[0] != 0)
1904 {
1905 /* If this is the real sender address, save the unrewritten version
1906 for use later in receive. Otherwise, set a flag so that rewriting the
1907 sender in verify_address() does not update sender_address. */
1908
1909 if (verify_sender_address == sender_address)
1910 sender_address_unrewritten = sender_address;
1911 else
1912 verify_options |= vopt_fake_sender;
1913
1914 if (success_on_redirect)
1915 verify_options |= vopt_success_on_redirect;
1916
1917 /* The recipient, qualify, and expn options are never set in
1918 verify_options. */
1919
1920 rc = verify_address(sender_vaddr, NULL, verify_options, callout,
1921 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, &routed);
1922
1923 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
1924
1925 if (rc == OK)
1926 {
1927 if (Ustrcmp(sender_vaddr->address, verify_sender_address) != 0)
1928 {
1929 DEBUG(D_acl) debug_printf("sender %s verified ok as %s\n",
1930 verify_sender_address, sender_vaddr->address);
1931 }
1932 else
1933 {
1934 DEBUG(D_acl) debug_printf("sender %s verified ok\n",
1935 verify_sender_address);
1936 }
1937 }
1938 else *basic_errno = sender_vaddr->basic_errno;
1939 }
1940 else rc = OK; /* Null sender */
1941
1942 /* Cache the result code */
1943
1944 if (routed) setflag(sender_vaddr, af_verify_routed);
1945 if (callout > 0) setflag(sender_vaddr, af_verify_callout);
1946 sender_vaddr->special_action = rc;
1947 sender_vaddr->next = sender_verified_list;
1948 sender_verified_list = sender_vaddr;
1949
1950 /* Restore the recipient address data, which might have been clobbered by
1951 the sender verification. */
1952
1953 deliver_address_data = save_address_data;
1954 }
1955
1956 /* Put the sender address_data value into $sender_address_data */
1957
1958 sender_address_data = sender_vaddr->p.address_data;
1959 }
1960
1961 /* A recipient address just gets a straightforward verify; again we must handle
1962 the DEFER overrides. */
1963
1964 else
1965 {
1966 address_item addr2;
1967
1968 if (success_on_redirect)
1969 verify_options |= vopt_success_on_redirect;
1970
1971 /* We must use a copy of the address for verification, because it might
1972 get rewritten. */
1973
1974 addr2 = *addr;
1975 rc = verify_address(&addr2, NULL, verify_options|vopt_is_recipient, callout,
1976 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, NULL);
1977 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
1978
1979 *basic_errno = addr2.basic_errno;
1980 *log_msgptr = addr2.message;
1981 *user_msgptr = (addr2.user_message != NULL)?
1982 addr2.user_message : addr2.message;
1983
1984 /* Allow details for temporary error if the address is so flagged. */
1985 if (testflag((&addr2), af_pass_message)) acl_temp_details = TRUE;
1986
1987 /* Make $address_data visible */
1988 deliver_address_data = addr2.p.address_data;
1989 }
1990
1991 /* We have a result from the relevant test. Handle defer overrides first. */
1992
1993 if (rc == DEFER && (defer_ok ||
1994 (callout_defer_ok && *basic_errno == ERRNO_CALLOUTDEFER)))
1995 {
1996 HDEBUG(D_acl) debug_printf("verify defer overridden by %s\n",
1997 defer_ok? "defer_ok" : "callout_defer_ok");
1998 rc = OK;
1999 }
2000
2001 /* If we've failed a sender, set up a recipient message, and point
2002 sender_verified_failed to the address item that actually failed. */
2003
2004 if (rc != OK && verify_sender_address != NULL)
2005 {
2006 if (rc != DEFER)
2007 {
2008 *log_msgptr = *user_msgptr = US"Sender verify failed";
2009 }
2010 else if (*basic_errno != ERRNO_CALLOUTDEFER)
2011 {
2012 *log_msgptr = *user_msgptr = US"Could not complete sender verify";
2013 }
2014 else
2015 {
2016 *log_msgptr = US"Could not complete sender verify callout";
2017 *user_msgptr = smtp_return_error_details? sender_vaddr->user_message :
2018 *log_msgptr;
2019 }
2020
2021 sender_verified_failed = sender_vaddr;
2022 }
2023
2024 /* Verifying an address messes up the values of $domain and $local_part,
2025 so reset them before returning if this is a RCPT ACL. */
2026
2027 if (addr != NULL)
2028 {
2029 deliver_domain = addr->domain;
2030 deliver_localpart = addr->local_part;
2031 }
2032 return rc;
2033
2034 /* Syntax errors in the verify argument come here. */
2035
2036 BAD_VERIFY:
2037 *log_msgptr = string_sprintf("expected \"sender[=address]\", \"recipient\", "
2038 "\"helo\", \"header_syntax\", \"header_sender\" or "
2039 "\"reverse_host_lookup\" at start of ACL condition "
2040 "\"verify %s\"", arg);
2041 return ERROR;
2042
2043 /* Options supplied when not allowed come here */
2044
2045 NO_OPTIONS:
2046 *log_msgptr = string_sprintf("unexpected '/' found in \"%s\" "
2047 "(this verify item has no options)", arg);
2048 return ERROR;
2049
2050 /* Calls in the wrong ACL come here */
2051
2052 WRONG_ACL:
2053 *log_msgptr = string_sprintf("cannot check header contents in ACL for %s "
2054 "(only possible in ACL for DATA)", acl_wherenames[where]);
2055 return ERROR;
2056 }
2057
2058
2059
2060
2061 /*************************************************
2062 * Check argument for control= modifier *
2063 *************************************************/
2064
2065 /* Called from acl_check_condition() below
2066
2067 Arguments:
2068 arg the argument string for control=
2069 pptr set to point to the terminating character
2070 where which ACL we are in
2071 log_msgptr for error messages
2072
2073 Returns: CONTROL_xxx value
2074 */
2075
2076 static int
2077 decode_control(uschar *arg, uschar **pptr, int where, uschar **log_msgptr)
2078 {
2079 int len;
2080 control_def *d;
2081
2082 for (d = controls_list;
2083 d < controls_list + sizeof(controls_list)/sizeof(control_def);
2084 d++)
2085 {
2086 len = Ustrlen(d->name);
2087 if (Ustrncmp(d->name, arg, len) == 0) break;
2088 }
2089
2090 if (d >= controls_list + sizeof(controls_list)/sizeof(control_def) ||
2091 (arg[len] != 0 && (!d->has_option || arg[len] != '/')))
2092 {
2093 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
2094 return CONTROL_ERROR;
2095 }
2096
2097 *pptr = arg + len;
2098 return d->value;
2099 }
2100
2101
2102
2103 /*************************************************
2104 * Handle rate limiting *
2105 *************************************************/
2106
2107 /* Called by acl_check_condition() below to calculate the result
2108 of the ACL ratelimit condition.
2109
2110 Note that the return value might be slightly unexpected: if the
2111 sender's rate is above the limit then the result is OK. This is
2112 similar to the dnslists condition, and is so that you can write
2113 ACL clauses like: defer ratelimit = 15 / 1h
2114
2115 Arguments:
2116 arg the option string for ratelimit=
2117 where ACL_WHERE_xxxx indicating which ACL this is
2118 log_msgptr for error messages
2119
2120 Returns: OK - Sender's rate is above limit
2121 FAIL - Sender's rate is below limit
2122 DEFER - Problem opening ratelimit database
2123 ERROR - Syntax error in options.
2124 */
2125
2126 static int
2127 acl_ratelimit(uschar *arg, int where, uschar **log_msgptr)
2128 {
2129 double limit, period;
2130 uschar *ss;
2131 uschar *key = NULL;
2132 int sep = '/';
2133 BOOL leaky = FALSE, strict = FALSE, noupdate = FALSE;
2134 BOOL per_byte = FALSE, per_cmd = FALSE, per_conn = FALSE, per_mail = FALSE;
2135 int old_pool, rc;
2136 tree_node **anchor, *t;
2137 open_db dbblock, *dbm;
2138 dbdata_ratelimit *dbd;
2139 struct timeval tv;
2140
2141 /* Parse the first two options and record their values in expansion
2142 variables. These variables allow the configuration to have informative
2143 error messages based on rate limits obtained from a table lookup. */
2144
2145 /* First is the maximum number of messages per period and maximum burst
2146 size, which must be greater than or equal to zero. Zero is useful for
2147 rate measurement as opposed to rate limiting. */
2148
2149 sender_rate_limit = string_nextinlist(&arg, &sep, NULL, 0);
2150 if (sender_rate_limit == NULL)
2151 limit = -1.0;
2152 else
2153 {
2154 limit = Ustrtod(sender_rate_limit, &ss);
2155 if (tolower(*ss) == 'k') { limit *= 1024.0; ss++; }
2156 else if (tolower(*ss) == 'm') { limit *= 1024.0*1024.0; ss++; }
2157 else if (tolower(*ss) == 'g') { limit *= 1024.0*1024.0*1024.0; ss++; }
2158 }
2159 if (limit < 0.0 || *ss != 0)
2160 {
2161 *log_msgptr = string_sprintf("syntax error in argument for "
2162 "\"ratelimit\" condition: \"%s\" is not a positive number",
2163 sender_rate_limit);
2164 return ERROR;
2165 }
2166
2167 /* Second is the rate measurement period and exponential smoothing time
2168 constant. This must be strictly greater than zero, because zero leads to
2169 run-time division errors. */
2170
2171 sender_rate_period = string_nextinlist(&arg, &sep, NULL, 0);
2172 if (sender_rate_period == NULL) period = -1.0;
2173 else period = readconf_readtime(sender_rate_period, 0, FALSE);
2174 if (period <= 0.0)
2175 {
2176 *log_msgptr = string_sprintf("syntax error in argument for "
2177 "\"ratelimit\" condition: \"%s\" is not a time value",
2178 sender_rate_period);
2179 return ERROR;
2180 }
2181
2182 /* Parse the other options. Should we check if the per_* options are being
2183 used in ACLs where they don't make sense, e.g. per_mail in the connect ACL? */
2184
2185 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2186 != NULL)
2187 {
2188 if (strcmpic(ss, US"leaky") == 0) leaky = TRUE;
2189 else if (strcmpic(ss, US"strict") == 0) strict = TRUE;
2190 else if (strcmpic(ss, US"noupdate") == 0) noupdate = TRUE;
2191 else if (strcmpic(ss, US"per_byte") == 0) per_byte = TRUE;
2192 else if (strcmpic(ss, US"per_cmd") == 0) per_cmd = TRUE;
2193 else if (strcmpic(ss, US"per_rcpt") == 0) per_cmd = TRUE; /* alias */
2194 else if (strcmpic(ss, US"per_conn") == 0) per_conn = TRUE;
2195 else if (strcmpic(ss, US"per_mail") == 0) per_mail = TRUE;
2196 else key = string_sprintf("%s", ss);
2197 }
2198
2199 if (leaky + strict > 1 || per_byte + per_cmd + per_conn + per_mail > 1)
2200 {
2201 *log_msgptr = US"conflicting options for \"ratelimit\" condition";
2202 return ERROR;
2203 }
2204
2205 /* Default option values */
2206
2207 if (!strict) leaky = TRUE;
2208 if (!per_byte && !per_cmd && !per_conn) per_mail = TRUE;
2209
2210 /* Create the lookup key. If there is no explicit key, use sender_host_address.
2211 If there is no sender_host_address (e.g. -bs or acl_not_smtp) then we simply
2212 omit it. The smoothing constant (sender_rate_period) and the per_xxx options
2213 are added to the key because they alter the meaning of the stored data. */
2214
2215 if (key == NULL)
2216 key = (sender_host_address == NULL)? US"" : sender_host_address;
2217
2218 key = string_sprintf("%s/%s/%s/%s",
2219 sender_rate_period,
2220 per_byte? US"per_byte" :
2221 per_cmd? US"per_cmd" :
2222 per_mail? US"per_mail" : US"per_conn",
2223 strict? US"strict" : US"leaky",
2224 key);
2225
2226 HDEBUG(D_acl) debug_printf("ratelimit condition limit=%.0f period=%.0f key=%s\n",
2227 limit, period, key);
2228
2229 /* See if we have already computed the rate by looking in the relevant tree.
2230 For per-connection rate limiting, store tree nodes and dbdata in the permanent
2231 pool so that they survive across resets. */
2232
2233 anchor = NULL;
2234 old_pool = store_pool;
2235
2236 if (per_conn)
2237 {
2238 anchor = &ratelimiters_conn;
2239 store_pool = POOL_PERM;
2240 }
2241 else if (per_mail || per_byte)
2242 anchor = &ratelimiters_mail;
2243 else if (per_cmd)
2244 anchor = &ratelimiters_cmd;
2245
2246 if (anchor != NULL && (t = tree_search(*anchor, key)) != NULL)
2247 {
2248 dbd = t->data.ptr;
2249 /* The following few lines duplicate some of the code below. */
2250 rc = (dbd->rate < limit)? FAIL : OK;
2251 store_pool = old_pool;
2252 sender_rate = string_sprintf("%.1f", dbd->rate);
2253 HDEBUG(D_acl)
2254 debug_printf("ratelimit found pre-computed rate %s\n", sender_rate);
2255 return rc;
2256 }
2257
2258 /* We aren't using a pre-computed rate, so get a previously recorded
2259 rate from the database, update it, and write it back when required. If there's
2260 no previous rate for this key, create one. */
2261
2262 dbm = dbfn_open(US"ratelimit", O_RDWR, &dbblock, TRUE);
2263 if (dbm == NULL)
2264 {
2265 store_pool = old_pool;
2266 sender_rate = NULL;
2267 HDEBUG(D_acl) debug_printf("ratelimit database not available\n");
2268 *log_msgptr = US"ratelimit database not available";
2269 return DEFER;
2270 }
2271 dbd = dbfn_read(dbm, key);
2272
2273 gettimeofday(&tv, NULL);
2274
2275 if (dbd == NULL)
2276 {
2277 HDEBUG(D_acl) debug_printf("ratelimit initializing new key's data\n");
2278 dbd = store_get(sizeof(dbdata_ratelimit));
2279 dbd->time_stamp = tv.tv_sec;
2280 dbd->time_usec = tv.tv_usec;
2281 dbd->rate = 0.0;
2282 }
2283 else
2284 {
2285 /* The smoothed rate is computed using an exponentially weighted moving
2286 average adjusted for variable sampling intervals. The standard EWMA for
2287 a fixed sampling interval is: f'(t) = (1 - a) * f(t) + a * f'(t - 1)
2288 where f() is the measured value and f'() is the smoothed value.
2289
2290 Old data decays out of the smoothed value exponentially, such that data n
2291 samples old is multiplied by a^n. The exponential decay time constant p
2292 is defined such that data p samples old is multiplied by 1/e, which means
2293 that a = exp(-1/p). We can maintain the same time constant for a variable
2294 sampling interval i by using a = exp(-i/p).
2295
2296 The rate we are measuring is messages per period, suitable for directly
2297 comparing with the limit. The average rate between now and the previous
2298 message is period / interval, which we feed into the EWMA as the sample.
2299
2300 It turns out that the number of messages required for the smoothed rate
2301 to reach the limit when they are sent in a burst is equal to the limit.
2302 This can be seen by analysing the value of the smoothed rate after N
2303 messages sent at even intervals. Let k = (1 - a) * p/i
2304
2305 rate_1 = (1 - a) * p/i + a * rate_0
2306 = k + a * rate_0
2307 rate_2 = k + a * rate_1
2308 = k + a * k + a^2 * rate_0
2309 rate_3 = k + a * k + a^2 * k + a^3 * rate_0
2310 rate_N = rate_0 * a^N + k * SUM(x=0..N-1)(a^x)
2311 = rate_0 * a^N + k * (1 - a^N) / (1 - a)
2312 = rate_0 * a^N + p/i * (1 - a^N)
2313
2314 When N is large, a^N -> 0 so rate_N -> p/i as desired.
2315
2316 rate_N = p/i + (rate_0 - p/i) * a^N
2317 a^N = (rate_N - p/i) / (rate_0 - p/i)
2318 N * -i/p = log((rate_N - p/i) / (rate_0 - p/i))
2319 N = p/i * log((rate_0 - p/i) / (rate_N - p/i))
2320
2321 Numerical analysis of the above equation, setting the computed rate to
2322 increase from rate_0 = 0 to rate_N = limit, shows that for large sending
2323 rates, p/i, the number of messages N = limit. So limit serves as both the
2324 maximum rate measured in messages per period, and the maximum number of
2325 messages that can be sent in a fast burst. */
2326
2327 double this_time = (double)tv.tv_sec
2328 + (double)tv.tv_usec / 1000000.0;
2329 double prev_time = (double)dbd->time_stamp
2330 + (double)dbd->time_usec / 1000000.0;
2331
2332 /* We must avoid division by zero, and deal gracefully with the clock going
2333 backwards. If we blunder ahead when time is in reverse then the computed
2334 rate will be bogus. To be safe we clamp interval to a very small number. */
2335
2336 double interval = this_time - prev_time <= 0.0 ? 1e-9
2337 : this_time - prev_time;
2338
2339 double i_over_p = interval / period;
2340 double a = exp(-i_over_p);
2341
2342 dbd->time_stamp = tv.tv_sec;
2343 dbd->time_usec = tv.tv_usec;
2344
2345 /* If we are measuring the rate in bytes per period, multiply the
2346 measured rate by the message size. If we don't know the message size
2347 then it's safe to just use a value of zero and let the recorded rate
2348 decay as if nothing happened. */
2349
2350 if (per_byte)
2351 dbd->rate = (message_size < 0 ? 0.0 : (double)message_size)
2352 * (1 - a) / i_over_p + a * dbd->rate;
2353 else if (per_cmd && where == ACL_WHERE_NOTSMTP)
2354 dbd->rate = (double)recipients_count
2355 * (1 - a) / i_over_p + a * dbd->rate;
2356 else
2357 dbd->rate = (1 - a) / i_over_p + a * dbd->rate;
2358 }
2359
2360 /* Clients sending at the limit are considered to be over the limit. This
2361 matters for edge cases such the first message sent by a client (which gets
2362 the initial rate of 0.0) when the rate limit is zero (i.e. the client should
2363 be completely blocked). */
2364
2365 rc = (dbd->rate < limit)? FAIL : OK;
2366
2367 /* Update the state if the rate is low or if we are being strict. If we
2368 are in leaky mode and the sender's rate is too high, we do not update
2369 the recorded rate in order to avoid an over-aggressive sender's retry
2370 rate preventing them from getting any email through. If noupdate is set,
2371 do not do any updates. */
2372
2373 if ((rc == FAIL || !leaky) && !noupdate)
2374 {
2375 dbfn_write(dbm, key, dbd, sizeof(dbdata_ratelimit));
2376 HDEBUG(D_acl) debug_printf("ratelimit db updated\n");
2377 }
2378 else
2379 {
2380 HDEBUG(D_acl) debug_printf("ratelimit db not updated: %s\n",
2381 noupdate? "noupdate set" : "over the limit, but leaky");
2382 }
2383
2384 dbfn_close(dbm);
2385
2386 /* Store the result in the tree for future reference, if necessary. */
2387
2388 if (anchor != NULL && !noupdate)
2389 {
2390 t = store_get(sizeof(tree_node) + Ustrlen(key));
2391 t->data.ptr = dbd;
2392 Ustrcpy(t->name, key);
2393 (void)tree_insertnode(anchor, t);
2394 }
2395
2396 /* We create the formatted version of the sender's rate very late in
2397 order to ensure that it is done using the correct storage pool. */
2398
2399 store_pool = old_pool;
2400 sender_rate = string_sprintf("%.1f", dbd->rate);
2401
2402 HDEBUG(D_acl)
2403 debug_printf("ratelimit computed rate %s\n", sender_rate);
2404
2405 return rc;
2406 }
2407
2408
2409
2410 /*************************************************
2411 * Handle conditions/modifiers on an ACL item *
2412 *************************************************/
2413
2414 /* Called from acl_check() below.
2415
2416 Arguments:
2417 verb ACL verb
2418 cb ACL condition block - if NULL, result is OK
2419 where where called from
2420 addr the address being checked for RCPT, or NULL
2421 level the nesting level
2422 epp pointer to pass back TRUE if "endpass" encountered
2423 (applies only to "accept" and "discard")
2424 user_msgptr user message pointer
2425 log_msgptr log message pointer
2426 basic_errno pointer to where to put verify error
2427
2428 Returns: OK - all conditions are met
2429 DISCARD - an "acl" condition returned DISCARD - only allowed
2430 for "accept" or "discard" verbs
2431 FAIL - at least one condition fails
2432 FAIL_DROP - an "acl" condition returned FAIL_DROP
2433 DEFER - can't tell at the moment (typically, lookup defer,
2434 but can be temporary callout problem)
2435 ERROR - ERROR from nested ACL or expansion failure or other
2436 error
2437 */
2438
2439 static int
2440 acl_check_condition(int verb, acl_condition_block *cb, int where,
2441 address_item *addr, int level, BOOL *epp, uschar **user_msgptr,
2442 uschar **log_msgptr, int *basic_errno)
2443 {
2444 uschar *user_message = NULL;
2445 uschar *log_message = NULL;
2446 uschar *p = NULL;
2447 int rc = OK;
2448 #ifdef WITH_CONTENT_SCAN
2449 int sep = '/';
2450 #endif
2451
2452 for (; cb != NULL; cb = cb->next)
2453 {
2454 uschar *arg;
2455 int control_type;
2456
2457 /* The message and log_message items set up messages to be used in
2458 case of rejection. They are expanded later. */
2459
2460 if (cb->type == ACLC_MESSAGE)
2461 {
2462 user_message = cb->arg;
2463 continue;
2464 }
2465
2466 if (cb->type == ACLC_LOG_MESSAGE)
2467 {
2468 log_message = cb->arg;
2469 continue;
2470 }
2471
2472 /* The endpass "condition" just sets a flag to show it occurred. This is
2473 checked at compile time to be on an "accept" or "discard" item. */
2474
2475 if (cb->type == ACLC_ENDPASS)
2476 {
2477 *epp = TRUE;
2478 continue;
2479 }
2480
2481 /* For other conditions and modifiers, the argument is expanded now for some
2482 of them, but not for all, because expansion happens down in some lower level
2483 checking functions in some cases. */
2484
2485 if (cond_expand_at_top[cb->type])
2486 {
2487 arg = expand_string(cb->arg);
2488 if (arg == NULL)
2489 {
2490 if (expand_string_forcedfail) continue;
2491 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s",
2492 cb->arg, expand_string_message);
2493 return search_find_defer? DEFER : ERROR;
2494 }
2495 }
2496 else arg = cb->arg;
2497
2498 /* Show condition, and expanded condition if it's different */
2499
2500 HDEBUG(D_acl)
2501 {
2502 int lhswidth = 0;
2503 debug_printf("check %s%s %n",
2504 (!cond_modifiers[cb->type] && cb->u.negated)? "!":"",
2505 conditions[cb->type], &lhswidth);
2506
2507 if (cb->type == ACLC_SET)
2508 {
2509 debug_printf("acl_%s ", cb->u.varname);
2510 lhswidth += 5 + Ustrlen(cb->u.varname);
2511 }
2512
2513 debug_printf("= %s\n", cb->arg);
2514
2515 if (arg != cb->arg)
2516 debug_printf("%.*s= %s\n", lhswidth,
2517 US" ", CS arg);
2518 }
2519
2520 /* Check that this condition makes sense at this time */
2521
2522 if ((cond_forbids[cb->type] & (1 << where)) != 0)
2523 {
2524 *log_msgptr = string_sprintf("cannot %s %s condition in %s ACL",
2525 cond_modifiers[cb->type]? "use" : "test",
2526 conditions[cb->type], acl_wherenames[where]);
2527 return ERROR;
2528 }
2529
2530 /* Run the appropriate test for each condition, or take the appropriate
2531 action for the remaining modifiers. */
2532
2533 switch(cb->type)
2534 {
2535 case ACLC_ADD_HEADER:
2536 setup_header(arg);
2537 break;
2538
2539 /* A nested ACL that returns "discard" makes sense only for an "accept" or
2540 "discard" verb. */
2541
2542 case ACLC_ACL:
2543 rc = acl_check_internal(where, addr, arg, level+1, user_msgptr, log_msgptr);
2544 if (rc == DISCARD && verb != ACL_ACCEPT && verb != ACL_DISCARD)
2545 {
2546 *log_msgptr = string_sprintf("nested ACL returned \"discard\" for "
2547 "\"%s\" command (only allowed with \"accept\" or \"discard\")",
2548 verbs[verb]);
2549 return ERROR;
2550 }
2551 break;
2552
2553 case ACLC_AUTHENTICATED:
2554 rc = (sender_host_authenticated == NULL)? FAIL :
2555 match_isinlist(sender_host_authenticated, &arg, 0, NULL, NULL, MCL_STRING,
2556 TRUE, NULL);
2557 break;
2558
2559 #ifdef EXPERIMENTAL_BRIGHTMAIL
2560 case ACLC_BMI_OPTIN:
2561 {
2562 int old_pool = store_pool;
2563 store_pool = POOL_PERM;
2564 bmi_current_optin = string_copy(arg);
2565 store_pool = old_pool;
2566 }
2567 break;
2568 #endif
2569
2570 case ACLC_CONDITION:
2571 if (Ustrspn(arg, "0123456789") == Ustrlen(arg)) /* Digits, or empty */
2572 rc = (Uatoi(arg) == 0)? FAIL : OK;
2573 else
2574 rc = (strcmpic(arg, US"no") == 0 ||
2575 strcmpic(arg, US"false") == 0)? FAIL :
2576 (strcmpic(arg, US"yes") == 0 ||
2577 strcmpic(arg, US"true") == 0)? OK : DEFER;
2578 if (rc == DEFER)
2579 *log_msgptr = string_sprintf("invalid \"condition\" value \"%s\"", arg);
2580 break;
2581
2582 case ACLC_CONTINUE: /* Always succeeds */
2583 break;
2584
2585 case ACLC_CONTROL:
2586 control_type = decode_control(arg, &p, where, log_msgptr);
2587
2588 /* Check if this control makes sense at this time */
2589
2590 if ((control_forbids[control_type] & (1 << where)) != 0)
2591 {
2592 *log_msgptr = string_sprintf("cannot use \"control=%s\" in %s ACL",
2593 controls[control_type], acl_wherenames[where]);
2594 return ERROR;
2595 }
2596
2597 switch(control_type)
2598 {
2599 case CONTROL_AUTH_UNADVERTISED:
2600 allow_auth_unadvertised = TRUE;
2601 break;
2602
2603 #ifdef EXPERIMENTAL_BRIGHTMAIL
2604 case CONTROL_BMI_RUN:
2605 bmi_run = 1;
2606 break;
2607 #endif
2608
2609 #ifdef EXPERIMENTAL_DOMAINKEYS
2610 case CONTROL_DK_VERIFY:
2611 dk_do_verify = 1;
2612 break;
2613 #endif
2614
2615 case CONTROL_ERROR:
2616 return ERROR;
2617
2618 case CONTROL_CASEFUL_LOCAL_PART:
2619 deliver_localpart = addr->cc_local_part;
2620 break;
2621
2622 case CONTROL_CASELOWER_LOCAL_PART:
2623 deliver_localpart = addr->lc_local_part;
2624 break;
2625
2626 case CONTROL_ENFORCE_SYNC:
2627 smtp_enforce_sync = TRUE;
2628 break;
2629
2630 case CONTROL_NO_ENFORCE_SYNC:
2631 smtp_enforce_sync = FALSE;
2632 break;
2633
2634 #ifdef WITH_CONTENT_SCAN
2635 case CONTROL_NO_MBOX_UNSPOOL:
2636 no_mbox_unspool = TRUE;
2637 break;
2638 #endif
2639
2640 case CONTROL_NO_MULTILINE:
2641 no_multiline_responses = TRUE;
2642 break;
2643
2644 case CONTROL_NO_PIPELINING:
2645 pipelining_enable = FALSE;
2646 break;
2647
2648 case CONTROL_NO_DELAY_FLUSH:
2649 disable_delay_flush = TRUE;
2650 break;
2651
2652 case CONTROL_NO_CALLOUT_FLUSH:
2653 disable_callout_flush = TRUE;
2654 break;
2655
2656 case CONTROL_FAKEDEFER:
2657 case CONTROL_FAKEREJECT:
2658 fake_response = (control_type == CONTROL_FAKEDEFER) ? DEFER : FAIL;
2659 if (*p == '/')
2660 {
2661 uschar *pp = p + 1;
2662 while (*pp != 0) pp++;
2663 fake_response_text = expand_string(string_copyn(p+1, pp-p-1));
2664 p = pp;
2665 }
2666 else
2667 {
2668 /* Explicitly reset to default string */
2669 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).";
2670 }
2671 break;
2672
2673 case CONTROL_FREEZE:
2674 deliver_freeze = TRUE;
2675 deliver_frozen_at = time(NULL);
2676 freeze_tell = freeze_tell_config; /* Reset to configured value */
2677 if (Ustrncmp(p, "/no_tell", 8) == 0)
2678 {
2679 p += 8;
2680 freeze_tell = NULL;
2681 }
2682 if (*p != 0)
2683 {
2684 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
2685 return ERROR;
2686 }
2687 break;
2688
2689 case CONTROL_QUEUE_ONLY:
2690 queue_only_policy = TRUE;
2691 break;
2692
2693 case CONTROL_SUBMISSION:
2694 originator_name = US"";
2695 submission_mode = TRUE;
2696 while (*p == '/')
2697 {
2698 if (Ustrncmp(p, "/sender_retain", 14) == 0)
2699 {
2700 p += 14;
2701 active_local_sender_retain = TRUE;
2702 active_local_from_check = FALSE;
2703 }
2704 else if (Ustrncmp(p, "/domain=", 8) == 0)
2705 {
2706 uschar *pp = p + 8;
2707 while (*pp != 0 && *pp != '/') pp++;
2708 submission_domain = string_copyn(p+8, pp-p-8);
2709 p = pp;
2710 }
2711 /* The name= option must be last, because it swallows the rest of
2712 the string. */
2713 else if (Ustrncmp(p, "/name=", 6) == 0)
2714 {
2715 uschar *pp = p + 6;
2716 while (*pp != 0) pp++;
2717 submission_name = string_copy(parse_fix_phrase(p+6, pp-p-6,
2718 big_buffer, big_buffer_size));
2719 p = pp;
2720 }
2721 else break;
2722 }
2723 if (*p != 0)
2724 {
2725 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
2726 return ERROR;
2727 }
2728 break;
2729
2730 case CONTROL_SUPPRESS_LOCAL_FIXUPS:
2731 suppress_local_fixups = TRUE;
2732 break;
2733 }
2734 break;
2735
2736 #ifdef WITH_CONTENT_SCAN
2737 case ACLC_DECODE:
2738 rc = mime_decode(&arg);
2739 break;
2740 #endif
2741
2742 case ACLC_DELAY:
2743 {
2744 int delay = readconf_readtime(arg, 0, FALSE);
2745 if (delay < 0)
2746 {
2747 *log_msgptr = string_sprintf("syntax error in argument for \"delay\" "
2748 "modifier: \"%s\" is not a time value", arg);
2749 return ERROR;
2750 }
2751 else
2752 {
2753 HDEBUG(D_acl) debug_printf("delay modifier requests %d-second delay\n",
2754 delay);
2755 if (host_checking)
2756 {
2757 HDEBUG(D_acl)
2758 debug_printf("delay skipped in -bh checking mode\n");
2759 }
2760
2761 /* It appears to be impossible to detect that a TCP/IP connection has
2762 gone away without reading from it. This means that we cannot shorten
2763 the delay below if the client goes away, because we cannot discover
2764 that the client has closed its end of the connection. (The connection
2765 is actually in a half-closed state, waiting for the server to close its
2766 end.) It would be nice to be able to detect this state, so that the
2767 Exim process is not held up unnecessarily. However, it seems that we
2768 can't. The poll() function does not do the right thing, and in any case
2769 it is not always available.
2770
2771 NOTE 1: If ever this state of affairs changes, remember that we may be
2772 dealing with stdin/stdout here, in addition to TCP/IP connections.
2773 Also, delays may be specified for non-SMTP input, where smtp_out and
2774 smtp_in will be NULL. Whatever is done must work in all cases.
2775
2776 NOTE 2: The added feature of flushing the output before a delay must
2777 apply only to SMTP input. Hence the test for smtp_out being non-NULL.
2778 */
2779
2780 else
2781 {
2782 if (smtp_out != NULL && !disable_delay_flush) mac_smtp_fflush();
2783 while (delay > 0) delay = sleep(delay);
2784 }
2785 }
2786 }
2787 break;
2788
2789 #ifdef WITH_OLD_DEMIME
2790 case ACLC_DEMIME:
2791 rc = demime(&arg);
2792 break;
2793 #endif
2794
2795 #ifdef EXPERIMENTAL_DOMAINKEYS
2796 case ACLC_DK_DOMAIN_SOURCE:
2797 if (dk_verify_block == NULL) { rc = FAIL; break; };
2798 /* check header source of domain against given string */
2799 switch (dk_verify_block->address_source) {
2800 case DK_EXIM_ADDRESS_FROM_FROM:
2801 rc = match_isinlist(US"from", &arg, 0, NULL,
2802 NULL, MCL_STRING, TRUE, NULL);
2803 break;
2804 case DK_EXIM_ADDRESS_FROM_SENDER:
2805 rc = match_isinlist(US"sender", &arg, 0, NULL,
2806 NULL, MCL_STRING, TRUE, NULL);
2807 break;
2808 case DK_EXIM_ADDRESS_NONE:
2809 rc = match_isinlist(US"none", &arg, 0, NULL,
2810 NULL, MCL_STRING, TRUE, NULL);
2811 break;
2812 }
2813 break;
2814
2815 case ACLC_DK_POLICY:
2816 if (dk_verify_block == NULL) { rc = FAIL; break; };
2817 /* check policy against given string, default FAIL */
2818 rc = FAIL;
2819 if (dk_verify_block->signsall)
2820 rc = match_isinlist(US"signsall", &arg, 0, NULL,
2821 NULL, MCL_STRING, TRUE, NULL);
2822 if (dk_verify_block->testing)
2823 rc = match_isinlist(US"testing", &arg, 0, NULL,
2824 NULL, MCL_STRING, TRUE, NULL);
2825 break;
2826
2827 case ACLC_DK_SENDER_DOMAINS:
2828 if (dk_verify_block == NULL) { rc = FAIL; break; };
2829 if (dk_verify_block->domain != NULL)
2830 rc = match_isinlist(dk_verify_block->domain, &arg, 0, &domainlist_anchor,
2831 NULL, MCL_DOMAIN, TRUE, NULL);
2832 else rc = FAIL;
2833 break;
2834
2835 case ACLC_DK_SENDER_LOCAL_PARTS:
2836 if (dk_verify_block == NULL) { rc = FAIL; break; };
2837 if (dk_verify_block->local_part != NULL)
2838 rc = match_isinlist(dk_verify_block->local_part, &arg, 0, &localpartlist_anchor,
2839 NULL, MCL_LOCALPART, TRUE, NULL);
2840 else rc = FAIL;
2841 break;
2842
2843 case ACLC_DK_SENDERS:
2844 if (dk_verify_block == NULL) { rc = FAIL; break; };
2845 if (dk_verify_block->address != NULL)
2846 rc = match_address_list(dk_verify_block->address, TRUE, TRUE, &arg, NULL, -1, 0, NULL);
2847 else rc = FAIL;
2848 break;
2849
2850 case ACLC_DK_STATUS:
2851 if (dk_verify_block == NULL) { rc = FAIL; break; };
2852 if (dk_verify_block->result > 0) {
2853 switch(dk_verify_block->result) {
2854 case DK_EXIM_RESULT_BAD_FORMAT:
2855 rc = match_isinlist(US"bad format", &arg, 0, NULL,
2856 NULL, MCL_STRING, TRUE, NULL);
2857 break;
2858 case DK_EXIM_RESULT_NO_KEY:
2859 rc = match_isinlist(US"no key", &arg, 0, NULL,
2860 NULL, MCL_STRING, TRUE, NULL);
2861 break;
2862 case DK_EXIM_RESULT_NO_SIGNATURE:
2863 rc = match_isinlist(US"no signature", &arg, 0, NULL,
2864 NULL, MCL_STRING, TRUE, NULL);
2865 break;
2866 case DK_EXIM_RESULT_REVOKED:
2867 rc = match_isinlist(US"revoked", &arg, 0, NULL,
2868 NULL, MCL_STRING, TRUE, NULL);
2869 break;
2870 case DK_EXIM_RESULT_NON_PARTICIPANT:
2871 rc = match_isinlist(US"non-participant", &arg, 0, NULL,
2872 NULL, MCL_STRING, TRUE, NULL);
2873 break;
2874 case DK_EXIM_RESULT_GOOD:
2875 rc = match_isinlist(US"good", &arg, 0, NULL,
2876 NULL, MCL_STRING, TRUE, NULL);
2877 break;
2878 case DK_EXIM_RESULT_BAD:
2879 rc = match_isinlist(US"bad", &arg, 0, NULL,
2880 NULL, MCL_STRING, TRUE, NULL);
2881 break;
2882 }
2883 }
2884 break;
2885 #endif
2886
2887 case ACLC_DNSLISTS:
2888 rc = verify_check_dnsbl(&arg);
2889 break;
2890
2891 case ACLC_DOMAINS:
2892 rc = match_isinlist(addr->domain, &arg, 0, &domainlist_anchor,
2893 addr->domain_cache, MCL_DOMAIN, TRUE, &deliver_domain_data);
2894 break;
2895
2896 /* The value in tls_cipher is the full cipher name, for example,
2897 TLSv1:DES-CBC3-SHA:168, whereas the values to test for are just the
2898 cipher names such as DES-CBC3-SHA. But program defensively. We don't know
2899 what may in practice come out of the SSL library - which at the time of
2900 writing is poorly documented. */
2901
2902 case ACLC_ENCRYPTED:
2903 if (tls_cipher == NULL) rc = FAIL; else
2904 {
2905 uschar *endcipher = NULL;
2906 uschar *cipher = Ustrchr(tls_cipher, ':');
2907 if (cipher == NULL) cipher = tls_cipher; else
2908 {
2909 endcipher = Ustrchr(++cipher, ':');
2910 if (endcipher != NULL) *endcipher = 0;
2911 }
2912 rc = match_isinlist(cipher, &arg, 0, NULL, NULL, MCL_STRING, TRUE, NULL);
2913 if (endcipher != NULL) *endcipher = ':';
2914 }
2915 break;
2916
2917 /* Use verify_check_this_host() instead of verify_check_host() so that
2918 we can pass over &host_data to catch any looked up data. Once it has been
2919 set, it retains its value so that it's still there if another ACL verb
2920 comes through here and uses the cache. However, we must put it into
2921 permanent store in case it is also expected to be used in a subsequent
2922 message in the same SMTP connection. */
2923
2924 case ACLC_HOSTS:
2925 rc = verify_check_this_host(&arg, sender_host_cache, NULL,
2926 (sender_host_address == NULL)? US"" : sender_host_address, &host_data);
2927 if (host_data != NULL) host_data = string_copy_malloc(host_data);
2928 break;
2929
2930 case ACLC_LOCAL_PARTS:
2931 rc = match_isinlist(addr->cc_local_part, &arg, 0,
2932 &localpartlist_anchor, addr->localpart_cache, MCL_LOCALPART, TRUE,
2933 &deliver_localpart_data);
2934 break;
2935
2936 case ACLC_LOG_REJECT_TARGET:
2937 {
2938 int logbits = 0;
2939 int sep = 0;
2940 uschar *s = arg;
2941 uschar *ss;
2942 while ((ss = string_nextinlist(&s, &sep, big_buffer, big_buffer_size))
2943 != NULL)
2944 {
2945 if (Ustrcmp(ss, "main") == 0) logbits |= LOG_MAIN;
2946 else if (Ustrcmp(ss, "panic") == 0) logbits |= LOG_PANIC;
2947 else if (Ustrcmp(ss, "reject") == 0) logbits |= LOG_REJECT;
2948 else
2949 {
2950 logbits |= LOG_MAIN|LOG_REJECT;
2951 log_write(0, LOG_MAIN|LOG_PANIC, "unknown log name \"%s\" in "
2952 "\"log_reject_target\" in %s ACL", ss, acl_wherenames[where]);
2953 }
2954 }
2955 log_reject_target = logbits;
2956 }
2957 break;
2958
2959 case ACLC_LOGWRITE:
2960 {
2961 int logbits = 0;
2962 uschar *s = arg;
2963 if (*s == ':')
2964 {
2965 s++;
2966 while (*s != ':')
2967 {
2968 if (Ustrncmp(s, "main", 4) == 0)
2969 { logbits |= LOG_MAIN; s += 4; }
2970 else if (Ustrncmp(s, "panic", 5) == 0)
2971 { logbits |= LOG_PANIC; s += 5; }
2972 else if (Ustrncmp(s, "reject", 6) == 0)
2973 { logbits |= LOG_REJECT; s += 6; }
2974 else
2975 {
2976 logbits = LOG_MAIN|LOG_PANIC;
2977 s = string_sprintf(":unknown log name in \"%s\" in "
2978 "\"logwrite\" in %s ACL", arg, acl_wherenames[where]);
2979 }
2980 if (*s == ',') s++;
2981 }
2982 s++;
2983 }
2984 while (isspace(*s)) s++;
2985
2986
2987 if (logbits == 0) logbits = LOG_MAIN;
2988 log_write(0, logbits, "%s", string_printing(s));
2989 }
2990 break;
2991
2992 #ifdef WITH_CONTENT_SCAN
2993 case ACLC_MALWARE:
2994 {
2995 /* Separate the regular expression and any optional parameters. */
2996 uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size);
2997 /* Run the malware backend. */
2998 rc = malware(&ss);
2999 /* Modify return code based upon the existance of options. */
3000 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
3001 != NULL) {
3002 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
3003 {
3004 /* FAIL so that the message is passed to the next ACL */
3005 rc = FAIL;
3006 }
3007 }
3008 }
3009 break;
3010
3011 case ACLC_MIME_REGEX:
3012 rc = mime_regex(&arg);
3013 break;
3014 #endif
3015
3016 case ACLC_RATELIMIT:
3017 rc = acl_ratelimit(arg, where, log_msgptr);
3018 break;
3019
3020 case ACLC_RECIPIENTS:
3021 rc = match_address_list(addr->address, TRUE, TRUE, &arg, NULL, -1, 0,
3022 &recipient_data);
3023 break;
3024
3025 #ifdef WITH_CONTENT_SCAN
3026 case ACLC_REGEX:
3027 rc = regex(&arg);
3028 break;
3029 #endif
3030
3031 case ACLC_SENDER_DOMAINS:
3032 {
3033 uschar *sdomain;
3034 sdomain = Ustrrchr(sender_address, '@');
3035 sdomain = (sdomain == NULL)? US"" : sdomain + 1;
3036 rc = match_isinlist(sdomain, &arg, 0, &domainlist_anchor,
3037 sender_domain_cache, MCL_DOMAIN, TRUE, NULL);
3038 }
3039 break;
3040
3041 case ACLC_SENDERS:
3042 rc = match_address_list(sender_address, TRUE, TRUE, &arg,
3043 sender_address_cache, -1, 0, &sender_data);
3044 break;
3045
3046 /* Connection variables must persist forever */
3047
3048 case ACLC_SET:
3049 {
3050 int old_pool = store_pool;
3051 if (cb->u.varname[0] == 'c') store_pool = POOL_PERM;
3052 acl_var_create(cb->u.varname)->data.ptr = string_copy(arg);
3053 store_pool = old_pool;
3054 }
3055 break;
3056
3057 #ifdef WITH_CONTENT_SCAN
3058 case ACLC_SPAM:
3059 {
3060 /* Seperate the regular expression and any optional parameters. */
3061 uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size);
3062 /* Run the spam backend. */
3063 rc = spam(&ss);
3064 /* Modify return code based upon the existance of options. */
3065 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
3066 != NULL) {
3067 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
3068 {
3069 /* FAIL so that the message is passed to the next ACL */
3070 rc = FAIL;
3071 }
3072 }
3073 }
3074 break;
3075 #endif
3076
3077 #ifdef EXPERIMENTAL_SPF
3078 case ACLC_SPF:
3079 rc = spf_process(&arg, sender_address);
3080 break;
3081 #endif
3082
3083 /* If the verb is WARN, discard any user message from verification, because
3084 such messages are SMTP responses, not header additions. The latter come
3085 only from explicit "message" modifiers. However, put the user message into
3086 $acl_verify_message so it can be used in subsequent conditions or modifiers
3087 (until something changes it). */
3088
3089 case ACLC_VERIFY:
3090 rc = acl_verify(where, addr, arg, user_msgptr, log_msgptr, basic_errno);
3091 acl_verify_message = *user_msgptr;
3092 if (verb == ACL_WARN) *user_msgptr = NULL;
3093 break;
3094
3095 default:
3096 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown "
3097 "condition %d", cb->type);
3098 break;
3099 }
3100
3101 /* If a condition was negated, invert OK/FAIL. */
3102
3103 if (!cond_modifiers[cb->type] && cb->u.negated)
3104 {
3105 if (rc == OK) rc = FAIL;
3106 else if (rc == FAIL || rc == FAIL_DROP) rc = OK;
3107 }
3108
3109 if (rc != OK) break; /* Conditions loop */
3110 }
3111
3112
3113 /* If the result is the one for which "message" and/or "log_message" are used,
3114 handle the values of these modifiers. If there isn't a log message set, we make
3115 it the same as the user message.
3116
3117 "message" is a user message that will be included in an SMTP response. Unless
3118 it is empty, it overrides any previously set user message.
3119
3120 "log_message" is a non-user message, and it adds to any existing non-user
3121 message that is already set.
3122
3123 Most verbs have but a single return for which the messages are relevant, but
3124 for "discard", it's useful to have the log message both when it succeeds and
3125 when it fails. For "accept", the message is used in the OK case if there is no
3126 "endpass", but (for backwards compatibility) in the FAIL case if "endpass" is
3127 present. */
3128
3129 if (*epp && rc == OK) user_message = NULL;
3130
3131 if (((1<<rc) & msgcond[verb]) != 0)
3132 {
3133 uschar *expmessage;
3134 uschar *old_user_msgptr = *user_msgptr;
3135 uschar *old_log_msgptr = (*log_msgptr != NULL)? *log_msgptr : old_user_msgptr;
3136
3137 /* If the verb is "warn", messages generated by conditions (verification or
3138 nested ACLs) are always discarded. This also happens for acceptance verbs
3139 when they actually do accept. Only messages specified at this level are used.
3140 However, the value of an existing message is available in $acl_verify_message
3141 during expansions. */
3142
3143 if (verb == ACL_WARN ||
3144 (rc == OK && (verb == ACL_ACCEPT || verb == ACL_DISCARD)))
3145 *log_msgptr = *user_msgptr = NULL;
3146
3147 if (user_message != NULL)
3148 {
3149 acl_verify_message = old_user_msgptr;
3150 expmessage = expand_string(user_message);
3151 if (expmessage == NULL)
3152 {
3153 if (!expand_string_forcedfail)
3154 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
3155 user_message, expand_string_message);
3156 }
3157 else if (expmessage[0] != 0) *user_msgptr = expmessage;
3158 }
3159
3160 if (log_message != NULL)
3161 {
3162 acl_verify_message = old_log_msgptr;
3163 expmessage = expand_string(log_message);
3164 if (expmessage == NULL)
3165 {
3166 if (!expand_string_forcedfail)
3167 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
3168 log_message, expand_string_message);
3169 }
3170 else if (expmessage[0] != 0)
3171 {
3172 *log_msgptr = (*log_msgptr == NULL)? expmessage :
3173 string_sprintf("%s: %s", expmessage, *log_msgptr);
3174 }
3175 }
3176
3177 /* If no log message, default it to the user message */
3178
3179 if (*log_msgptr == NULL) *log_msgptr = *user_msgptr;
3180 }
3181
3182 acl_verify_message = NULL;
3183 return rc;
3184 }
3185
3186
3187
3188
3189
3190 /*************************************************
3191 * Get line from a literal ACL *
3192 *************************************************/
3193
3194 /* This function is passed to acl_read() in order to extract individual lines
3195 of a literal ACL, which we access via static pointers. We can destroy the
3196 contents because this is called only once (the compiled ACL is remembered).
3197
3198 This code is intended to treat the data in the same way as lines in the main
3199 Exim configuration file. That is:
3200
3201 . Leading spaces are ignored.
3202
3203 . A \ at the end of a line is a continuation - trailing spaces after the \
3204 are permitted (this is because I don't believe in making invisible things
3205 significant). Leading spaces on the continued part of a line are ignored.
3206
3207 . Physical lines starting (significantly) with # are totally ignored, and
3208 may appear within a sequence of backslash-continued lines.
3209
3210 . Blank lines are ignored, but will end a sequence of continuations.
3211
3212 Arguments: none
3213 Returns: a pointer to the next line
3214 */
3215
3216
3217 static uschar *acl_text; /* Current pointer in the text */
3218 static uschar *acl_text_end; /* Points one past the terminating '0' */
3219
3220
3221 static uschar *
3222 acl_getline(void)
3223 {
3224 uschar *yield;
3225
3226 /* This loop handles leading blank lines and comments. */
3227
3228 for(;;)
3229 {
3230 while (isspace(*acl_text)) acl_text++; /* Leading spaces/empty lines */
3231 if (*acl_text == 0) return NULL; /* No more data */
3232 yield = acl_text; /* Potential data line */
3233
3234 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3235
3236 /* If we hit the end before a newline, we have the whole logical line. If
3237 it's a comment, there's no more data to be given. Otherwise, yield it. */
3238
3239 if (*acl_text == 0) return (*yield == '#')? NULL : yield;
3240
3241 /* After reaching a newline, end this loop if the physical line does not
3242 start with '#'. If it does, it's a comment, and the loop continues. */
3243
3244 if (*yield != '#') break;
3245 }
3246
3247 /* This loop handles continuations. We know we have some real data, ending in
3248 newline. See if there is a continuation marker at the end (ignoring trailing
3249 white space). We know that *yield is not white space, so no need to test for
3250 cont > yield in the backwards scanning loop. */
3251
3252 for(;;)
3253 {
3254 uschar *cont;
3255 for (cont = acl_text - 1; isspace(*cont); cont--);
3256
3257 /* If no continuation follows, we are done. Mark the end of the line and
3258 return it. */
3259
3260 if (*cont != '\\')
3261 {
3262 *acl_text++ = 0;
3263 return yield;
3264 }
3265
3266 /* We have encountered a continuation. Skip over whitespace at the start of
3267 the next line, and indeed the whole of the next line or lines if they are
3268 comment lines. */
3269
3270 for (;;)
3271 {
3272 while (*(++acl_text) == ' ' || *acl_text == '\t');
3273 if (*acl_text != '#') break;
3274 while (*(++acl_text) != 0 && *acl_text != '\n');
3275 }
3276
3277 /* We have the start of a continuation line. Move all the rest of the data
3278 to join onto the previous line, and then find its end. If the end is not a
3279 newline, we are done. Otherwise loop to look for another continuation. */
3280
3281 memmove(cont, acl_text, acl_text_end - acl_text);
3282 acl_text_end -= acl_text - cont;
3283 acl_text = cont;
3284 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3285 if (*acl_text == 0) return yield;
3286 }
3287
3288 /* Control does not reach here */
3289 }
3290
3291
3292
3293
3294
3295 /*************************************************
3296 * Check access using an ACL *
3297 *************************************************/
3298
3299 /* This function is called from address_check. It may recurse via
3300 acl_check_condition() - hence the use of a level to stop looping. The ACL is
3301 passed as a string which is expanded. A forced failure implies no access check
3302 is required. If the result is a single word, it is taken as the name of an ACL
3303 which is sought in the global ACL tree. Otherwise, it is taken as literal ACL
3304 text, complete with newlines, and parsed as such. In both cases, the ACL check
3305 is then run. This function uses an auxiliary function for acl_read() to call
3306 for reading individual lines of a literal ACL. This is acl_getline(), which
3307 appears immediately above.
3308
3309 Arguments:
3310 where where called from
3311 addr address item when called from RCPT; otherwise NULL
3312 s the input string; NULL is the same as an empty ACL => DENY
3313 level the nesting level
3314 user_msgptr where to put a user error (for SMTP response)
3315 log_msgptr where to put a logging message (not for SMTP response)
3316
3317 Returns: OK access is granted
3318 DISCARD access is apparently granted...
3319 FAIL access is denied
3320 FAIL_DROP access is denied; drop the connection
3321 DEFER can't tell at the moment
3322 ERROR disaster
3323 */
3324
3325 static int
3326 acl_check_internal(int where, address_item *addr, uschar *s, int level,
3327 uschar **user_msgptr, uschar **log_msgptr)
3328 {
3329 int fd = -1;
3330 acl_block *acl = NULL;
3331 uschar *acl_name = US"inline ACL";
3332 uschar *ss;
3333
3334 /* Catch configuration loops */
3335
3336 if (level > 20)
3337 {
3338 *log_msgptr = US"ACL nested too deep: possible loop";
3339 return ERROR;
3340 }
3341
3342 if (s == NULL)
3343 {
3344 HDEBUG(D_acl) debug_printf("ACL is NULL: implicit DENY\n");
3345 return FAIL;
3346 }
3347
3348 /* At top level, we expand the incoming string. At lower levels, it has already
3349 been expanded as part of condition processing. */
3350
3351 if (level == 0)
3352 {
3353 ss = expand_string(s);
3354 if (ss == NULL)
3355 {
3356 if (expand_string_forcedfail) return OK;
3357 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s", s,
3358 expand_string_message);
3359 return ERROR;
3360 }
3361 }
3362 else ss = s;
3363
3364 while (isspace(*ss))ss++;
3365
3366 /* If we can't find a named ACL, the default is to parse it as an inline one.
3367 (Unless it begins with a slash; non-existent files give rise to an error.) */
3368
3369 acl_text = ss;
3370
3371 /* Handle the case of a string that does not contain any spaces. Look for a
3372 named ACL among those read from the configuration, or a previously read file.
3373 It is possible that the pointer to the ACL is NULL if the configuration
3374 contains a name with no data. If not found, and the text begins with '/',
3375 read an ACL from a file, and save it so it can be re-used. */
3376
3377 if (Ustrchr(ss, ' ') == NULL)
3378 {
3379 tree_node *t = tree_search(acl_anchor, ss);
3380 if (t != NULL)
3381 {
3382 acl = (acl_block *)(t->data.ptr);
3383 if (acl == NULL)
3384 {
3385 HDEBUG(D_acl) debug_printf("ACL \"%s\" is empty: implicit DENY\n", ss);
3386 return FAIL;
3387 }
3388 acl_name = string_sprintf("ACL \"%s\"", ss);
3389 HDEBUG(D_acl) debug_printf("using ACL \"%s\"\n", ss);
3390 }
3391
3392 else if (*ss == '/')
3393 {
3394 struct stat statbuf;
3395 fd = Uopen(ss, O_RDONLY, 0);
3396 if (fd < 0)
3397 {
3398 *log_msgptr = string_sprintf("failed to open ACL file \"%s\": %s", ss,
3399 strerror(errno));
3400 return ERROR;
3401 }
3402
3403 if (fstat(fd, &statbuf) != 0)
3404 {
3405 *log_msgptr = string_sprintf("failed to fstat ACL file \"%s\": %s", ss,
3406 strerror(errno));
3407 return ERROR;
3408 }
3409
3410 acl_text = store_get(statbuf.st_size + 1);
3411 acl_text_end = acl_text + statbuf.st_size + 1;
3412
3413 if (read(fd, acl_text, statbuf.st_size) != statbuf.st_size)
3414 {
3415 *log_msgptr = string_sprintf("failed to read ACL file \"%s\": %s",
3416 ss, strerror(errno));
3417 return ERROR;
3418 }
3419 acl_text[statbuf.st_size] = 0;
3420 (void)close(fd);
3421
3422 acl_name = string_sprintf("ACL \"%s\"", ss);
3423 HDEBUG(D_acl) debug_printf("read ACL from file %s\n", ss);
3424 }
3425 }
3426
3427 /* Parse an ACL that is still in text form. If it came from a file, remember it
3428 in the ACL tree, having read it into the POOL_PERM store pool so that it
3429 persists between multiple messages. */
3430
3431 if (acl == NULL)
3432 {
3433 int old_pool = store_pool;
3434 if (fd >= 0) store_pool = POOL_PERM;
3435 acl = acl_read(acl_getline, log_msgptr);
3436 store_pool = old_pool;
3437 if (acl == NULL && *log_msgptr != NULL) return ERROR;
3438 if (fd >= 0)
3439 {
3440 tree_node *t = store_get_perm(sizeof(tree_node) + Ustrlen(ss));
3441 Ustrcpy(t->name, ss);
3442 t->data.ptr = acl;
3443 (void)tree_insertnode(&acl_anchor, t);
3444 }
3445 }
3446
3447 /* Now we have an ACL to use. It's possible it may be NULL. */
3448
3449 while (acl != NULL)
3450 {
3451 int cond;
3452 int basic_errno = 0;
3453 BOOL endpass_seen = FALSE;
3454
3455 *log_msgptr = *user_msgptr = NULL;
3456 acl_temp_details = FALSE;
3457
3458 if (where == ACL_WHERE_QUIT &&
3459 acl->verb != ACL_ACCEPT &&
3460 acl->verb != ACL_WARN)
3461 {
3462 *log_msgptr = string_sprintf("\"%s\" is not allowed in a QUIT ACL",
3463 verbs[acl->verb]);
3464 return ERROR;
3465 }
3466
3467 HDEBUG(D_acl) debug_printf("processing \"%s\"\n", verbs[acl->verb]);
3468
3469 /* Clear out any search error message from a previous check before testing
3470 this condition. */
3471
3472 search_error_message = NULL;
3473 cond = acl_check_condition(acl->verb, acl->condition, where, addr, level,
3474 &endpass_seen, user_msgptr, log_msgptr, &basic_errno);
3475
3476 /* Handle special returns: DEFER causes a return except on a WARN verb;
3477 ERROR always causes a return. */
3478
3479 switch (cond)
3480 {
3481 case DEFER:
3482 HDEBUG(D_acl) debug_printf("%s: condition test deferred\n", verbs[acl->verb]);
3483 if (basic_errno != ERRNO_CALLOUTDEFER)
3484 {
3485 if (search_error_message != NULL && *search_error_message != 0)
3486 *log_msgptr = search_error_message;
3487 if (smtp_return_error_details) acl_temp_details = TRUE;
3488 }
3489 else
3490 {
3491 acl_temp_details = TRUE;
3492 }
3493 if (acl->verb != ACL_WARN) return DEFER;
3494 break;
3495
3496 default: /* Paranoia */
3497 case ERROR:
3498 HDEBUG(D_acl) debug_printf("%s: condition test error\n", verbs[acl->verb]);
3499 return ERROR;
3500
3501 case OK:
3502 HDEBUG(D_acl) debug_printf("%s: condition test succeeded\n",
3503 verbs[acl->verb]);
3504 break;
3505
3506 case FAIL:
3507 HDEBUG(D_acl) debug_printf("%s: condition test failed\n", verbs[acl->verb]);
3508 break;
3509
3510 /* DISCARD and DROP can happen only from a nested ACL condition, and
3511 DISCARD can happen only for an "accept" or "discard" verb. */
3512
3513 case DISCARD:
3514 HDEBUG(D_acl) debug_printf("%s: condition test yielded \"discard\"\n",
3515 verbs[acl->verb]);
3516 break;
3517
3518 case FAIL_DROP:
3519 HDEBUG(D_acl) debug_printf("%s: condition test yielded \"drop\"\n",
3520 verbs[acl->verb]);
3521 break;
3522 }
3523
3524 /* At this point, cond for most verbs is either OK or FAIL or (as a result of
3525 a nested ACL condition) FAIL_DROP. However, for WARN, cond may be DEFER, and
3526 for ACCEPT and DISCARD, it may be DISCARD after a nested ACL call. */
3527
3528 switch(acl->verb)
3529 {
3530 case ACL_ACCEPT:
3531 if (cond == OK || cond == DISCARD) return cond;
3532 if (endpass_seen)
3533 {
3534 HDEBUG(D_acl) debug_printf("accept: endpass encountered - denying access\n");
3535 return cond;
3536 }
3537 break;
3538
3539 case ACL_DEFER:
3540 if (cond == OK)
3541 {
3542 acl_temp_details = TRUE;
3543 return DEFER;
3544 }
3545 break;
3546
3547 case ACL_DENY:
3548 if (cond == OK) return FAIL;
3549 break;
3550
3551 case ACL_DISCARD:
3552 if (cond == OK || cond == DISCARD) return DISCARD;
3553 if (endpass_seen)
3554 {
3555 HDEBUG(D_acl) debug_printf("discard: endpass encountered - denying access\n");
3556 return cond;
3557 }
3558 break;
3559
3560 case ACL_DROP:
3561 if (cond == OK) return FAIL_DROP;
3562 break;
3563
3564 case ACL_REQUIRE:
3565 if (cond != OK) return cond;
3566 break;
3567
3568 case ACL_WARN:
3569 if (cond == OK)
3570 acl_warn(where, *user_msgptr, *log_msgptr);
3571 else if (cond == DEFER && (log_extra_selector & LX_acl_warn_skipped) != 0)
3572 log_write(0, LOG_MAIN, "%s Warning: ACL \"warn\" statement skipped: "
3573 "condition test deferred%s%s", host_and_ident(TRUE),
3574 (*log_msgptr == NULL)? US"" : US": ",
3575 (*log_msgptr == NULL)? US"" : *log_msgptr);
3576 *log_msgptr = *user_msgptr = NULL; /* In case implicit DENY follows */
3577 break;
3578
3579 default:
3580 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown verb %d",
3581 acl->verb);
3582 break;
3583 }
3584
3585 /* Pass to the next ACL item */
3586
3587 acl = acl->next;
3588 }
3589
3590 /* We have reached the end of the ACL. This is an implicit DENY. */
3591
3592 HDEBUG(D_acl) debug_printf("end of %s: implicit DENY\n", acl_name);
3593 return FAIL;
3594 }
3595
3596
3597 /*************************************************
3598 * Check access using an ACL *
3599 *************************************************/
3600
3601 /* This is the external interface for ACL checks. It sets up an address and the
3602 expansions for $domain and $local_part when called after RCPT, then calls
3603 acl_check_internal() to do the actual work.
3604
3605 Arguments:
3606 where ACL_WHERE_xxxx indicating where called from
3607 recipient RCPT address for RCPT check, else NULL
3608 s the input string; NULL is the same as an empty ACL => DENY
3609 user_msgptr where to put a user error (for SMTP response)
3610 log_msgptr where to put a logging message (not for SMTP response)
3611
3612 Returns: OK access is granted by an ACCEPT verb
3613 DISCARD access is granted by a DISCARD verb
3614 FAIL access is denied
3615 FAIL_DROP access is denied; drop the connection
3616 DEFER can't tell at the moment
3617 ERROR disaster
3618 */
3619
3620 int
3621 acl_check(int where, uschar *recipient, uschar *s, uschar **user_msgptr,
3622 uschar **log_msgptr)
3623 {
3624 int rc;
3625 address_item adb;
3626 address_item *addr = NULL;
3627
3628 *user_msgptr = *log_msgptr = NULL;
3629 sender_verified_failed = NULL;
3630 ratelimiters_cmd = NULL;
3631 log_reject_target = LOG_MAIN|LOG_REJECT;
3632
3633 if (where == ACL_WHERE_RCPT)
3634 {
3635 adb = address_defaults;
3636 addr = &adb;
3637 addr->address = recipient;
3638 if (deliver_split_address(addr) == DEFER)
3639 {
3640 *log_msgptr = US"defer in percent_hack_domains check";
3641 return DEFER;
3642 }
3643 deliver_domain = addr->domain;
3644 deliver_localpart = addr->local_part;
3645 }
3646
3647 rc = acl_check_internal(where, addr, s, 0, user_msgptr, log_msgptr);
3648
3649 deliver_domain = deliver_localpart = deliver_address_data =
3650 sender_address_data = NULL;
3651
3652 /* A DISCARD response is permitted only for message ACLs, excluding the PREDATA
3653 ACL, which is really in the middle of an SMTP command. */
3654
3655 if (rc == DISCARD)
3656 {
3657 if (where > ACL_WHERE_NOTSMTP || where == ACL_WHERE_PREDATA)
3658 {
3659 log_write(0, LOG_MAIN|LOG_PANIC, "\"discard\" verb not allowed in %s "
3660 "ACL", acl_wherenames[where]);
3661 return ERROR;
3662 }
3663 return DISCARD;
3664 }
3665
3666 /* A DROP response is not permitted from MAILAUTH */
3667
3668 if (rc == FAIL_DROP && where == ACL_WHERE_MAILAUTH)
3669 {
3670 log_write(0, LOG_MAIN|LOG_PANIC, "\"drop\" verb not allowed in %s "
3671 "ACL", acl_wherenames[where]);
3672 return ERROR;
3673 }
3674
3675 /* Before giving a response, take a look at the length of any user message, and
3676 split it up into multiple lines if possible. */
3677
3678 *user_msgptr = string_split_message(*user_msgptr);
3679 if (fake_response != OK)
3680 fake_response_text = string_split_message(fake_response_text);
3681
3682 return rc;
3683 }
3684
3685
3686
3687 /*************************************************
3688 * Create ACL variable *
3689 *************************************************/
3690
3691 /* Create an ACL variable or reuse an existing one. ACL variables are in a
3692 binary tree (see tree.c) with acl_var_c and acl_var_m as root nodes.
3693
3694 Argument:
3695 name pointer to the variable's name, starting with c or m
3696
3697 Returns the pointer to variable's tree node
3698 */
3699
3700 tree_node *
3701 acl_var_create(uschar *name)
3702 {
3703 tree_node *node, **root;
3704 root = (name[0] == 'c')? &acl_var_c : &acl_var_m;
3705 node = tree_search(*root, name);
3706 if (node == NULL)
3707 {
3708 node = store_get(sizeof(tree_node) + Ustrlen(name));
3709 Ustrcpy(node->name, name);
3710 (void)tree_insertnode(root, node);
3711 }
3712 node->data.ptr = NULL;
3713 return node;
3714 }
3715
3716
3717
3718 /*************************************************
3719 * Write an ACL variable in spool format *
3720 *************************************************/
3721
3722 /* This function is used as a callback for tree_walk when writing variables to
3723 the spool file. To retain spool file compatibility, what is written is -aclc or
3724 -aclm followed by the rest of the name and the data length, space separated,
3725 then the value itself, starting on a new line, and terminated by an additional
3726 newline. When we had only numbered ACL variables, the first line might look
3727 like this: "-aclc 5 20". Now it might be "-aclc foo 20" for the variable called
3728 acl_cfoo.
3729
3730 Arguments:
3731 name of the variable
3732 value of the variable
3733 ctx FILE pointer (as a void pointer)
3734
3735 Returns: nothing
3736 */
3737
3738 void
3739 acl_var_write(uschar *name, uschar *value, void *ctx)
3740 {
3741 FILE *f = (FILE *)ctx;
3742 fprintf(f, "-acl%c %s %d\n%s\n", name[0], name+1, Ustrlen(value), value);
3743 }
3744
3745 /* End of acl.c */