Fix ACL "condition =" for negative number values. Bug 1005
[exim.git] / src / src / acl.c
1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
4
5 /* Copyright (c) University of Cambridge 1995 - 2013 */
6 /* See the file NOTICE for conditions of use and distribution. */
7
8 /* Code for handling Access Control Lists (ACLs) */
9
10 #include "exim.h"
11
12
13 /* Default callout timeout */
14
15 #define CALLOUT_TIMEOUT_DEFAULT 30
16
17 /* ACL verb codes - keep in step with the table of verbs that follows */
18
19 enum { ACL_ACCEPT, ACL_DEFER, ACL_DENY, ACL_DISCARD, ACL_DROP, ACL_REQUIRE,
20 ACL_WARN };
21
22 /* ACL verbs */
23
24 static uschar *verbs[] = {
25 US"accept",
26 US"defer",
27 US"deny",
28 US"discard",
29 US"drop",
30 US"require",
31 US"warn" };
32
33 /* For each verb, the conditions for which "message" or "log_message" are used
34 are held as a bitmap. This is to avoid expanding the strings unnecessarily. For
35 "accept", the FAIL case is used only after "endpass", but that is selected in
36 the code. */
37
38 static int msgcond[] = {
39 (1<<OK) | (1<<FAIL) | (1<<FAIL_DROP), /* accept */
40 (1<<OK), /* defer */
41 (1<<OK), /* deny */
42 (1<<OK) | (1<<FAIL) | (1<<FAIL_DROP), /* discard */
43 (1<<OK), /* drop */
44 (1<<FAIL) | (1<<FAIL_DROP), /* require */
45 (1<<OK) /* warn */
46 };
47
48 /* ACL condition and modifier codes - keep in step with the table that
49 follows, and the cond_expand_at_top and uschar cond_modifiers tables lower
50 down. */
51
52 enum { ACLC_ACL,
53 ACLC_ADD_HEADER,
54 ACLC_AUTHENTICATED,
55 #ifdef EXPERIMENTAL_BRIGHTMAIL
56 ACLC_BMI_OPTIN,
57 #endif
58 ACLC_CONDITION,
59 ACLC_CONTINUE,
60 ACLC_CONTROL,
61 #ifdef EXPERIMENTAL_DCC
62 ACLC_DCC,
63 #endif
64 #ifdef WITH_CONTENT_SCAN
65 ACLC_DECODE,
66 #endif
67 ACLC_DELAY,
68 #ifdef WITH_OLD_DEMIME
69 ACLC_DEMIME,
70 #endif
71 #ifndef DISABLE_DKIM
72 ACLC_DKIM_SIGNER,
73 ACLC_DKIM_STATUS,
74 #endif
75 #ifdef EXPERIMENTAL_DMARC
76 ACLC_DMARC_STATUS,
77 #endif
78 ACLC_DNSLISTS,
79 ACLC_DOMAINS,
80 ACLC_ENCRYPTED,
81 ACLC_ENDPASS,
82 ACLC_HOSTS,
83 ACLC_LOCAL_PARTS,
84 ACLC_LOG_MESSAGE,
85 ACLC_LOG_REJECT_TARGET,
86 ACLC_LOGWRITE,
87 #ifdef WITH_CONTENT_SCAN
88 ACLC_MALWARE,
89 #endif
90 ACLC_MESSAGE,
91 #ifdef WITH_CONTENT_SCAN
92 ACLC_MIME_REGEX,
93 #endif
94 ACLC_RATELIMIT,
95 ACLC_RECIPIENTS,
96 #ifdef WITH_CONTENT_SCAN
97 ACLC_REGEX,
98 #endif
99 ACLC_REMOVE_HEADER,
100 ACLC_SENDER_DOMAINS,
101 ACLC_SENDERS,
102 ACLC_SET,
103 #ifdef WITH_CONTENT_SCAN
104 ACLC_SPAM,
105 #endif
106 #ifdef EXPERIMENTAL_SPF
107 ACLC_SPF,
108 ACLC_SPF_GUESS,
109 #endif
110 ACLC_UDPSEND,
111 ACLC_VERIFY };
112
113 /* ACL conditions/modifiers: "delay", "control", "continue", "endpass",
114 "message", "log_message", "log_reject_target", "logwrite", and "set" are
115 modifiers that look like conditions but always return TRUE. They are used for
116 their side effects. */
117
118 static uschar *conditions[] = {
119 US"acl",
120 US"add_header",
121 US"authenticated",
122 #ifdef EXPERIMENTAL_BRIGHTMAIL
123 US"bmi_optin",
124 #endif
125 US"condition",
126 US"continue",
127 US"control",
128 #ifdef EXPERIMENTAL_DCC
129 US"dcc",
130 #endif
131 #ifdef WITH_CONTENT_SCAN
132 US"decode",
133 #endif
134 US"delay",
135 #ifdef WITH_OLD_DEMIME
136 US"demime",
137 #endif
138 #ifndef DISABLE_DKIM
139 US"dkim_signers",
140 US"dkim_status",
141 #endif
142 #ifdef EXPERIMENTAL_DMARC
143 US"dmarc_status",
144 #endif
145 US"dnslists",
146 US"domains",
147 US"encrypted",
148 US"endpass",
149 US"hosts",
150 US"local_parts",
151 US"log_message",
152 US"log_reject_target",
153 US"logwrite",
154 #ifdef WITH_CONTENT_SCAN
155 US"malware",
156 #endif
157 US"message",
158 #ifdef WITH_CONTENT_SCAN
159 US"mime_regex",
160 #endif
161 US"ratelimit",
162 US"recipients",
163 #ifdef WITH_CONTENT_SCAN
164 US"regex",
165 #endif
166 US"remove_header",
167 US"sender_domains", US"senders", US"set",
168 #ifdef WITH_CONTENT_SCAN
169 US"spam",
170 #endif
171 #ifdef EXPERIMENTAL_SPF
172 US"spf",
173 US"spf_guess",
174 #endif
175 US"udpsend",
176 US"verify" };
177
178
179 /* Return values from decode_control(); keep in step with the table of names
180 that follows! */
181
182 enum {
183 CONTROL_AUTH_UNADVERTISED,
184 #ifdef EXPERIMENTAL_BRIGHTMAIL
185 CONTROL_BMI_RUN,
186 #endif
187 CONTROL_DEBUG,
188 #ifndef DISABLE_DKIM
189 CONTROL_DKIM_VERIFY,
190 #endif
191 #ifdef EXPERIMENTAL_DMARC
192 CONTROL_DMARC_VERIFY,
193 CONTROL_DMARC_FORENSIC,
194 #endif
195 CONTROL_DSCP,
196 CONTROL_ERROR,
197 CONTROL_CASEFUL_LOCAL_PART,
198 CONTROL_CASELOWER_LOCAL_PART,
199 CONTROL_CUTTHROUGH_DELIVERY,
200 CONTROL_ENFORCE_SYNC,
201 CONTROL_NO_ENFORCE_SYNC,
202 CONTROL_FREEZE,
203 CONTROL_QUEUE_ONLY,
204 CONTROL_SUBMISSION,
205 CONTROL_SUPPRESS_LOCAL_FIXUPS,
206 #ifdef WITH_CONTENT_SCAN
207 CONTROL_NO_MBOX_UNSPOOL,
208 #endif
209 CONTROL_FAKEDEFER,
210 CONTROL_FAKEREJECT,
211 CONTROL_NO_MULTILINE,
212 CONTROL_NO_PIPELINING,
213 CONTROL_NO_DELAY_FLUSH,
214 CONTROL_NO_CALLOUT_FLUSH
215 };
216
217 /* ACL control names; keep in step with the table above! This list is used for
218 turning ids into names. The actual list of recognized names is in the variable
219 control_def controls_list[] below. The fact that there are two lists is a mess
220 and should be tidied up. */
221
222 static uschar *controls[] = {
223 US"allow_auth_unadvertised",
224 #ifdef EXPERIMENTAL_BRIGHTMAIL
225 US"bmi_run",
226 #endif
227 US"debug",
228 #ifndef DISABLE_DKIM
229 US"dkim_disable_verify",
230 #endif
231 #ifdef EXPERIMENTAL_DMARC
232 US"dmarc_disable_verify",
233 US"dmarc_enable_forensic",
234 #endif
235 US"dscp",
236 US"error",
237 US"caseful_local_part",
238 US"caselower_local_part",
239 US"cutthrough_delivery",
240 US"enforce_sync",
241 US"no_enforce_sync",
242 US"freeze",
243 US"queue_only",
244 US"submission",
245 US"suppress_local_fixups",
246 #ifdef WITH_CONTENT_SCAN
247 US"no_mbox_unspool",
248 #endif
249 US"fakedefer",
250 US"fakereject",
251 US"no_multiline_responses",
252 US"no_pipelining",
253 US"no_delay_flush",
254 US"no_callout_flush"
255 };
256
257 /* Flags to indicate for which conditions/modifiers a string expansion is done
258 at the outer level. In the other cases, expansion already occurs in the
259 checking functions. */
260
261 static uschar cond_expand_at_top[] = {
262 FALSE, /* acl */
263 TRUE, /* add_header */
264 FALSE, /* authenticated */
265 #ifdef EXPERIMENTAL_BRIGHTMAIL
266 TRUE, /* bmi_optin */
267 #endif
268 TRUE, /* condition */
269 TRUE, /* continue */
270 TRUE, /* control */
271 #ifdef EXPERIMENTAL_DCC
272 TRUE, /* dcc */
273 #endif
274 #ifdef WITH_CONTENT_SCAN
275 TRUE, /* decode */
276 #endif
277 TRUE, /* delay */
278 #ifdef WITH_OLD_DEMIME
279 TRUE, /* demime */
280 #endif
281 #ifndef DISABLE_DKIM
282 TRUE, /* dkim_signers */
283 TRUE, /* dkim_status */
284 #endif
285 #ifdef EXPERIMENTAL_DMARC
286 TRUE, /* dmarc_status */
287 #endif
288 TRUE, /* dnslists */
289 FALSE, /* domains */
290 FALSE, /* encrypted */
291 TRUE, /* endpass */
292 FALSE, /* hosts */
293 FALSE, /* local_parts */
294 TRUE, /* log_message */
295 TRUE, /* log_reject_target */
296 TRUE, /* logwrite */
297 #ifdef WITH_CONTENT_SCAN
298 TRUE, /* malware */
299 #endif
300 TRUE, /* message */
301 #ifdef WITH_CONTENT_SCAN
302 TRUE, /* mime_regex */
303 #endif
304 TRUE, /* ratelimit */
305 FALSE, /* recipients */
306 #ifdef WITH_CONTENT_SCAN
307 TRUE, /* regex */
308 #endif
309 TRUE, /* remove_header */
310 FALSE, /* sender_domains */
311 FALSE, /* senders */
312 TRUE, /* set */
313 #ifdef WITH_CONTENT_SCAN
314 TRUE, /* spam */
315 #endif
316 #ifdef EXPERIMENTAL_SPF
317 TRUE, /* spf */
318 TRUE, /* spf_guess */
319 #endif
320 TRUE, /* udpsend */
321 TRUE /* verify */
322 };
323
324 /* Flags to identify the modifiers */
325
326 static uschar cond_modifiers[] = {
327 FALSE, /* acl */
328 TRUE, /* add_header */
329 FALSE, /* authenticated */
330 #ifdef EXPERIMENTAL_BRIGHTMAIL
331 TRUE, /* bmi_optin */
332 #endif
333 FALSE, /* condition */
334 TRUE, /* continue */
335 TRUE, /* control */
336 #ifdef EXPERIMENTAL_DCC
337 FALSE, /* dcc */
338 #endif
339 #ifdef WITH_CONTENT_SCAN
340 FALSE, /* decode */
341 #endif
342 TRUE, /* delay */
343 #ifdef WITH_OLD_DEMIME
344 FALSE, /* demime */
345 #endif
346 #ifndef DISABLE_DKIM
347 FALSE, /* dkim_signers */
348 FALSE, /* dkim_status */
349 #endif
350 #ifdef EXPERIMENTAL_DMARC
351 FALSE, /* dmarc_status */
352 #endif
353 FALSE, /* dnslists */
354 FALSE, /* domains */
355 FALSE, /* encrypted */
356 TRUE, /* endpass */
357 FALSE, /* hosts */
358 FALSE, /* local_parts */
359 TRUE, /* log_message */
360 TRUE, /* log_reject_target */
361 TRUE, /* logwrite */
362 #ifdef WITH_CONTENT_SCAN
363 FALSE, /* malware */
364 #endif
365 TRUE, /* message */
366 #ifdef WITH_CONTENT_SCAN
367 FALSE, /* mime_regex */
368 #endif
369 FALSE, /* ratelimit */
370 FALSE, /* recipients */
371 #ifdef WITH_CONTENT_SCAN
372 FALSE, /* regex */
373 #endif
374 TRUE, /* remove_header */
375 FALSE, /* sender_domains */
376 FALSE, /* senders */
377 TRUE, /* set */
378 #ifdef WITH_CONTENT_SCAN
379 FALSE, /* spam */
380 #endif
381 #ifdef EXPERIMENTAL_SPF
382 FALSE, /* spf */
383 FALSE, /* spf_guess */
384 #endif
385 TRUE, /* udpsend */
386 FALSE /* verify */
387 };
388
389 /* Bit map vector of which conditions and modifiers are not allowed at certain
390 times. For each condition and modifier, there's a bitmap of dis-allowed times.
391 For some, it is easier to specify the negation of a small number of allowed
392 times. */
393
394 static unsigned int cond_forbids[] = {
395 0, /* acl */
396
397 (unsigned int)
398 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* add_header */
399 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
400 #ifdef EXPERIMENTAL_PRDR
401 (1<<ACL_WHERE_PRDR)|
402 #endif
403 (1<<ACL_WHERE_MIME)|(1<<ACL_WHERE_NOTSMTP)|
404 (1<<ACL_WHERE_DKIM)|
405 (1<<ACL_WHERE_NOTSMTP_START)),
406
407 (1<<ACL_WHERE_NOTSMTP)| /* authenticated */
408 (1<<ACL_WHERE_NOTSMTP_START)|
409 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO),
410
411 #ifdef EXPERIMENTAL_BRIGHTMAIL
412 (1<<ACL_WHERE_AUTH)| /* bmi_optin */
413 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
414 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_MIME)|
415 #ifdef EXPERIMENTAL_PRDR
416 (1<<ACL_WHERE_PRDR)|
417 #endif
418 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
419 (1<<ACL_WHERE_MAILAUTH)|
420 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
421 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_PREDATA)|
422 (1<<ACL_WHERE_NOTSMTP_START),
423 #endif
424
425 0, /* condition */
426
427 0, /* continue */
428
429 /* Certain types of control are always allowed, so we let it through
430 always and check in the control processing itself. */
431
432 0, /* control */
433
434 #ifdef EXPERIMENTAL_DCC
435 (unsigned int)
436 ~((1<<ACL_WHERE_DATA)| /* dcc */
437 #ifdef EXPERIMENTAL_PRDR
438 (1<<ACL_WHERE_PRDR)|
439 #endif /* EXPERIMENTAL_PRDR */
440 (1<<ACL_WHERE_NOTSMTP)),
441 #endif
442
443 #ifdef WITH_CONTENT_SCAN
444 (unsigned int)
445 ~(1<<ACL_WHERE_MIME), /* decode */
446 #endif
447
448 (1<<ACL_WHERE_NOTQUIT), /* delay */
449
450 #ifdef WITH_OLD_DEMIME
451 (unsigned int)
452 ~((1<<ACL_WHERE_DATA)| /* demime */
453 #ifdef EXPERIMENTAL_PRDR
454 (1<<ACL_WHERE_PRDR)|
455 #endif /* EXPERIMENTAL_PRDR */
456 (1<<ACL_WHERE_NOTSMTP)),
457 #endif
458
459 #ifndef DISABLE_DKIM
460 (unsigned int)
461 ~(1<<ACL_WHERE_DKIM), /* dkim_signers */
462
463 (unsigned int)
464 ~(1<<ACL_WHERE_DKIM), /* dkim_status */
465 #endif
466
467 #ifdef EXPERIMENTAL_DMARC
468 (unsigned int)
469 ~(1<<ACL_WHERE_DATA), /* dmarc_status */
470 #endif
471
472 (1<<ACL_WHERE_NOTSMTP)| /* dnslists */
473 (1<<ACL_WHERE_NOTSMTP_START),
474
475 (unsigned int)
476 ~((1<<ACL_WHERE_RCPT) /* domains */
477 #ifdef EXPERIMENTAL_PRDR
478 |(1<<ACL_WHERE_PRDR)
479 #endif
480 ),
481
482 (1<<ACL_WHERE_NOTSMTP)| /* encrypted */
483 (1<<ACL_WHERE_CONNECT)|
484 (1<<ACL_WHERE_NOTSMTP_START)|
485 (1<<ACL_WHERE_HELO),
486
487 0, /* endpass */
488
489 (1<<ACL_WHERE_NOTSMTP)| /* hosts */
490 (1<<ACL_WHERE_NOTSMTP_START),
491
492 (unsigned int)
493 ~((1<<ACL_WHERE_RCPT) /* local_parts */
494 #ifdef EXPERIMENTAL_PRDR
495 |(1<<ACL_WHERE_PRDR)
496 #endif
497 ),
498
499 0, /* log_message */
500
501 0, /* log_reject_target */
502
503 0, /* logwrite */
504
505 #ifdef WITH_CONTENT_SCAN
506 (unsigned int)
507 ~((1<<ACL_WHERE_DATA)| /* malware */
508 #ifdef EXPERIMENTAL_PRDR
509 (1<<ACL_WHERE_PRDR)|
510 #endif /* EXPERIMENTAL_PRDR */
511 (1<<ACL_WHERE_NOTSMTP)),
512 #endif
513
514 0, /* message */
515
516 #ifdef WITH_CONTENT_SCAN
517 (unsigned int)
518 ~(1<<ACL_WHERE_MIME), /* mime_regex */
519 #endif
520
521 0, /* ratelimit */
522
523 (unsigned int)
524 ~(1<<ACL_WHERE_RCPT), /* recipients */
525
526 #ifdef WITH_CONTENT_SCAN
527 (unsigned int)
528 ~((1<<ACL_WHERE_DATA)| /* regex */
529 #ifdef EXPERIMENTAL_PRDR
530 (1<<ACL_WHERE_PRDR)|
531 #endif /* EXPERIMENTAL_PRDR */
532 (1<<ACL_WHERE_NOTSMTP)|
533 (1<<ACL_WHERE_MIME)),
534 #endif
535
536 (unsigned int)
537 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* remove_header */
538 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
539 #ifdef EXPERIMENTAL_PRDR
540 (1<<ACL_WHERE_PRDR)|
541 #endif
542 (1<<ACL_WHERE_MIME)|(1<<ACL_WHERE_NOTSMTP)|
543 (1<<ACL_WHERE_NOTSMTP_START)),
544
545 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* sender_domains */
546 (1<<ACL_WHERE_HELO)|
547 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
548 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
549 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
550
551 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* senders */
552 (1<<ACL_WHERE_HELO)|
553 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
554 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
555 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
556
557 0, /* set */
558
559 #ifdef WITH_CONTENT_SCAN
560 (unsigned int)
561 ~((1<<ACL_WHERE_DATA)| /* spam */
562 #ifdef EXPERIMENTAL_PRDR
563 (1<<ACL_WHERE_PRDR)|
564 #endif /* EXPERIMENTAL_PRDR */
565 (1<<ACL_WHERE_NOTSMTP)),
566 #endif
567
568 #ifdef EXPERIMENTAL_SPF
569 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* spf */
570 (1<<ACL_WHERE_HELO)|
571 (1<<ACL_WHERE_MAILAUTH)|
572 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
573 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY)|
574 (1<<ACL_WHERE_NOTSMTP)|
575 (1<<ACL_WHERE_NOTSMTP_START),
576
577 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* spf_guess */
578 (1<<ACL_WHERE_HELO)|
579 (1<<ACL_WHERE_MAILAUTH)|
580 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
581 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY)|
582 (1<<ACL_WHERE_NOTSMTP)|
583 (1<<ACL_WHERE_NOTSMTP_START),
584 #endif
585
586 0, /* udpsend */
587
588 /* Certain types of verify are always allowed, so we let it through
589 always and check in the verify function itself */
590
591 0 /* verify */
592 };
593
594
595 /* Bit map vector of which controls are not allowed at certain times. For
596 each control, there's a bitmap of dis-allowed times. For some, it is easier to
597 specify the negation of a small number of allowed times. */
598
599 static unsigned int control_forbids[] = {
600 (unsigned int)
601 ~((1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)), /* allow_auth_unadvertised */
602
603 #ifdef EXPERIMENTAL_BRIGHTMAIL
604 0, /* bmi_run */
605 #endif
606
607 0, /* debug */
608
609 #ifndef DISABLE_DKIM
610 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* dkim_disable_verify */
611 #ifdef EXPERIMENTAL_PRDR
612 (1<<ACL_WHERE_PRDR)|
613 #endif /* EXPERIMENTAL_PRDR */
614 (1<<ACL_WHERE_NOTSMTP_START),
615 #endif
616
617 #ifdef EXPERIMENTAL_DMARC
618 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* dmarc_disable_verify */
619 (1<<ACL_WHERE_NOTSMTP_START),
620 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* dmarc_enable_forensic */
621 (1<<ACL_WHERE_NOTSMTP_START),
622 #endif
623
624 (1<<ACL_WHERE_NOTSMTP)|
625 (1<<ACL_WHERE_NOTSMTP_START)|
626 (1<<ACL_WHERE_NOTQUIT), /* dscp */
627
628 0, /* error */
629
630 (unsigned int)
631 ~(1<<ACL_WHERE_RCPT), /* caseful_local_part */
632
633 (unsigned int)
634 ~(1<<ACL_WHERE_RCPT), /* caselower_local_part */
635
636 (unsigned int)
637 0, /* cutthrough_delivery */
638
639 (1<<ACL_WHERE_NOTSMTP)| /* enforce_sync */
640 (1<<ACL_WHERE_NOTSMTP_START),
641
642 (1<<ACL_WHERE_NOTSMTP)| /* no_enforce_sync */
643 (1<<ACL_WHERE_NOTSMTP_START),
644
645 (unsigned int)
646 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* freeze */
647 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
648 // (1<<ACL_WHERE_PRDR)| /* Not allow one user to freeze for all */
649 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)),
650
651 (unsigned int)
652 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* queue_only */
653 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
654 // (1<<ACL_WHERE_PRDR)| /* Not allow one user to freeze for all */
655 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)),
656
657 (unsigned int)
658 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* submission */
659 (1<<ACL_WHERE_PREDATA)),
660
661 (unsigned int)
662 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* suppress_local_fixups */
663 (1<<ACL_WHERE_PREDATA)|
664 (1<<ACL_WHERE_NOTSMTP_START)),
665
666 #ifdef WITH_CONTENT_SCAN
667 (unsigned int)
668 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* no_mbox_unspool */
669 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
670 // (1<<ACL_WHERE_PRDR)| /* Not allow one user to freeze for all */
671 (1<<ACL_WHERE_MIME)),
672 #endif
673
674 (unsigned int)
675 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakedefer */
676 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
677 #ifdef EXPERIMENTAL_PRDR
678 (1<<ACL_WHERE_PRDR)|
679 #endif /* EXPERIMENTAL_PRDR */
680 (1<<ACL_WHERE_MIME)),
681
682 (unsigned int)
683 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakereject */
684 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
685 #ifdef EXPERIMENTAL_PRDR
686 (1<<ACL_WHERE_PRDR)|
687 #endif /* EXPERIMENTAL_PRDR */
688 (1<<ACL_WHERE_MIME)),
689
690 (1<<ACL_WHERE_NOTSMTP)| /* no_multiline */
691 (1<<ACL_WHERE_NOTSMTP_START),
692
693 (1<<ACL_WHERE_NOTSMTP)| /* no_pipelining */
694 (1<<ACL_WHERE_NOTSMTP_START),
695
696 (1<<ACL_WHERE_NOTSMTP)| /* no_delay_flush */
697 (1<<ACL_WHERE_NOTSMTP_START),
698
699 (1<<ACL_WHERE_NOTSMTP)| /* no_callout_flush */
700 (1<<ACL_WHERE_NOTSMTP_START)
701 };
702
703 /* Structure listing various control arguments, with their characteristics. */
704
705 typedef struct control_def {
706 uschar *name;
707 int value; /* CONTROL_xxx value */
708 BOOL has_option; /* Has /option(s) following */
709 } control_def;
710
711 static control_def controls_list[] = {
712 { US"allow_auth_unadvertised", CONTROL_AUTH_UNADVERTISED, FALSE },
713 #ifdef EXPERIMENTAL_BRIGHTMAIL
714 { US"bmi_run", CONTROL_BMI_RUN, FALSE },
715 #endif
716 { US"debug", CONTROL_DEBUG, TRUE },
717 #ifndef DISABLE_DKIM
718 { US"dkim_disable_verify", CONTROL_DKIM_VERIFY, FALSE },
719 #endif
720 #ifdef EXPERIMENTAL_DMARC
721 { US"dmarc_disable_verify", CONTROL_DMARC_VERIFY, FALSE },
722 { US"dmarc_enable_forensic", CONTROL_DMARC_FORENSIC, FALSE },
723 #endif
724 { US"dscp", CONTROL_DSCP, TRUE },
725 { US"caseful_local_part", CONTROL_CASEFUL_LOCAL_PART, FALSE },
726 { US"caselower_local_part", CONTROL_CASELOWER_LOCAL_PART, FALSE },
727 { US"enforce_sync", CONTROL_ENFORCE_SYNC, FALSE },
728 { US"freeze", CONTROL_FREEZE, TRUE },
729 { US"no_callout_flush", CONTROL_NO_CALLOUT_FLUSH, FALSE },
730 { US"no_delay_flush", CONTROL_NO_DELAY_FLUSH, FALSE },
731 { US"no_enforce_sync", CONTROL_NO_ENFORCE_SYNC, FALSE },
732 { US"no_multiline_responses", CONTROL_NO_MULTILINE, FALSE },
733 { US"no_pipelining", CONTROL_NO_PIPELINING, FALSE },
734 { US"queue_only", CONTROL_QUEUE_ONLY, FALSE },
735 #ifdef WITH_CONTENT_SCAN
736 { US"no_mbox_unspool", CONTROL_NO_MBOX_UNSPOOL, FALSE },
737 #endif
738 { US"fakedefer", CONTROL_FAKEDEFER, TRUE },
739 { US"fakereject", CONTROL_FAKEREJECT, TRUE },
740 { US"submission", CONTROL_SUBMISSION, TRUE },
741 { US"suppress_local_fixups", CONTROL_SUPPRESS_LOCAL_FIXUPS, FALSE },
742 { US"cutthrough_delivery", CONTROL_CUTTHROUGH_DELIVERY, FALSE }
743 };
744
745 /* Support data structures for Client SMTP Authorization. acl_verify_csa()
746 caches its result in a tree to avoid repeated DNS queries. The result is an
747 integer code which is used as an index into the following tables of
748 explanatory strings and verification return codes. */
749
750 static tree_node *csa_cache = NULL;
751
752 enum { CSA_UNKNOWN, CSA_OK, CSA_DEFER_SRV, CSA_DEFER_ADDR,
753 CSA_FAIL_EXPLICIT, CSA_FAIL_DOMAIN, CSA_FAIL_NOADDR, CSA_FAIL_MISMATCH };
754
755 /* The acl_verify_csa() return code is translated into an acl_verify() return
756 code using the following table. It is OK unless the client is definitely not
757 authorized. This is because CSA is supposed to be optional for sending sites,
758 so recipients should not be too strict about checking it - especially because
759 DNS problems are quite likely to occur. It's possible to use $csa_status in
760 further ACL conditions to distinguish ok, unknown, and defer if required, but
761 the aim is to make the usual configuration simple. */
762
763 static int csa_return_code[] = {
764 OK, OK, OK, OK,
765 FAIL, FAIL, FAIL, FAIL
766 };
767
768 static uschar *csa_status_string[] = {
769 US"unknown", US"ok", US"defer", US"defer",
770 US"fail", US"fail", US"fail", US"fail"
771 };
772
773 static uschar *csa_reason_string[] = {
774 US"unknown",
775 US"ok",
776 US"deferred (SRV lookup failed)",
777 US"deferred (target address lookup failed)",
778 US"failed (explicit authorization required)",
779 US"failed (host name not authorized)",
780 US"failed (no authorized addresses)",
781 US"failed (client address mismatch)"
782 };
783
784 /* Options for the ratelimit condition. Note that there are two variants of
785 the per_rcpt option, depending on the ACL that is used to measure the rate.
786 However any ACL must be able to look up per_rcpt rates in /noupdate mode,
787 so the two variants must have the same internal representation as well as
788 the same configuration string. */
789
790 enum {
791 RATE_PER_WHAT, RATE_PER_CLASH, RATE_PER_ADDR, RATE_PER_BYTE, RATE_PER_CMD,
792 RATE_PER_CONN, RATE_PER_MAIL, RATE_PER_RCPT, RATE_PER_ALLRCPTS
793 };
794
795 #define RATE_SET(var,new) \
796 (((var) == RATE_PER_WHAT) ? ((var) = RATE_##new) : ((var) = RATE_PER_CLASH))
797
798 static uschar *ratelimit_option_string[] = {
799 US"?", US"!", US"per_addr", US"per_byte", US"per_cmd",
800 US"per_conn", US"per_mail", US"per_rcpt", US"per_rcpt"
801 };
802
803 /* Enable recursion between acl_check_internal() and acl_check_condition() */
804
805 static int acl_check_wargs(int, address_item *, uschar *, int, uschar **,
806 uschar **);
807
808
809 /*************************************************
810 * Pick out name from list *
811 *************************************************/
812
813 /* Use a binary chop method
814
815 Arguments:
816 name name to find
817 list list of names
818 end size of list
819
820 Returns: offset in list, or -1 if not found
821 */
822
823 static int
824 acl_checkname(uschar *name, uschar **list, int end)
825 {
826 int start = 0;
827
828 while (start < end)
829 {
830 int mid = (start + end)/2;
831 int c = Ustrcmp(name, list[mid]);
832 if (c == 0) return mid;
833 if (c < 0) end = mid; else start = mid + 1;
834 }
835
836 return -1;
837 }
838
839
840 /*************************************************
841 * Read and parse one ACL *
842 *************************************************/
843
844 /* This function is called both from readconf in order to parse the ACLs in the
845 configuration file, and also when an ACL is encountered dynamically (e.g. as
846 the result of an expansion). It is given a function to call in order to
847 retrieve the lines of the ACL. This function handles skipping comments and
848 blank lines (where relevant).
849
850 Arguments:
851 func function to get next line of ACL
852 error where to put an error message
853
854 Returns: pointer to ACL, or NULL
855 NULL can be legal (empty ACL); in this case error will be NULL
856 */
857
858 acl_block *
859 acl_read(uschar *(*func)(void), uschar **error)
860 {
861 acl_block *yield = NULL;
862 acl_block **lastp = &yield;
863 acl_block *this = NULL;
864 acl_condition_block *cond;
865 acl_condition_block **condp = NULL;
866 uschar *s;
867
868 *error = NULL;
869
870 while ((s = (*func)()) != NULL)
871 {
872 int v, c;
873 BOOL negated = FALSE;
874 uschar *saveline = s;
875 uschar name[64];
876
877 /* Conditions (but not verbs) are allowed to be negated by an initial
878 exclamation mark. */
879
880 while (isspace(*s)) s++;
881 if (*s == '!')
882 {
883 negated = TRUE;
884 s++;
885 }
886
887 /* Read the name of a verb or a condition, or the start of a new ACL, which
888 can be started by a name, or by a macro definition. */
889
890 s = readconf_readname(name, sizeof(name), s);
891 if (*s == ':' || (isupper(name[0]) && *s == '=')) return yield;
892
893 /* If a verb is unrecognized, it may be another condition or modifier that
894 continues the previous verb. */
895
896 v = acl_checkname(name, verbs, sizeof(verbs)/sizeof(char *));
897 if (v < 0)
898 {
899 if (this == NULL)
900 {
901 *error = string_sprintf("unknown ACL verb \"%s\" in \"%s\"", name,
902 saveline);
903 return NULL;
904 }
905 }
906
907 /* New verb */
908
909 else
910 {
911 if (negated)
912 {
913 *error = string_sprintf("malformed ACL line \"%s\"", saveline);
914 return NULL;
915 }
916 this = store_get(sizeof(acl_block));
917 *lastp = this;
918 lastp = &(this->next);
919 this->next = NULL;
920 this->verb = v;
921 this->condition = NULL;
922 condp = &(this->condition);
923 if (*s == 0) continue; /* No condition on this line */
924 if (*s == '!')
925 {
926 negated = TRUE;
927 s++;
928 }
929 s = readconf_readname(name, sizeof(name), s); /* Condition name */
930 }
931
932 /* Handle a condition or modifier. */
933
934 c = acl_checkname(name, conditions, sizeof(conditions)/sizeof(char *));
935 if (c < 0)
936 {
937 *error = string_sprintf("unknown ACL condition/modifier in \"%s\"",
938 saveline);
939 return NULL;
940 }
941
942 /* The modifiers may not be negated */
943
944 if (negated && cond_modifiers[c])
945 {
946 *error = string_sprintf("ACL error: negation is not allowed with "
947 "\"%s\"", conditions[c]);
948 return NULL;
949 }
950
951 /* ENDPASS may occur only with ACCEPT or DISCARD. */
952
953 if (c == ACLC_ENDPASS &&
954 this->verb != ACL_ACCEPT &&
955 this->verb != ACL_DISCARD)
956 {
957 *error = string_sprintf("ACL error: \"%s\" is not allowed with \"%s\"",
958 conditions[c], verbs[this->verb]);
959 return NULL;
960 }
961
962 cond = store_get(sizeof(acl_condition_block));
963 cond->next = NULL;
964 cond->type = c;
965 cond->u.negated = negated;
966
967 *condp = cond;
968 condp = &(cond->next);
969
970 /* The "set" modifier is different in that its argument is "name=value"
971 rather than just a value, and we can check the validity of the name, which
972 gives us a variable name to insert into the data block. The original ACL
973 variable names were acl_c0 ... acl_c9 and acl_m0 ... acl_m9. This was
974 extended to 20 of each type, but after that people successfully argued for
975 arbitrary names. In the new scheme, the names must start with acl_c or acl_m.
976 After that, we allow alphanumerics and underscores, but the first character
977 after c or m must be a digit or an underscore. This retains backwards
978 compatibility. */
979
980 if (c == ACLC_SET)
981 {
982 uschar *endptr;
983
984 if (Ustrncmp(s, "acl_c", 5) != 0 &&
985 Ustrncmp(s, "acl_m", 5) != 0)
986 {
987 *error = string_sprintf("invalid variable name after \"set\" in ACL "
988 "modifier \"set %s\" (must start \"acl_c\" or \"acl_m\")", s);
989 return NULL;
990 }
991
992 endptr = s + 5;
993 if (!isdigit(*endptr) && *endptr != '_')
994 {
995 *error = string_sprintf("invalid variable name after \"set\" in ACL "
996 "modifier \"set %s\" (digit or underscore must follow acl_c or acl_m)",
997 s);
998 return NULL;
999 }
1000
1001 while (*endptr != 0 && *endptr != '=' && !isspace(*endptr))
1002 {
1003 if (!isalnum(*endptr) && *endptr != '_')
1004 {
1005 *error = string_sprintf("invalid character \"%c\" in variable name "
1006 "in ACL modifier \"set %s\"", *endptr, s);
1007 return NULL;
1008 }
1009 endptr++;
1010 }
1011
1012 cond->u.varname = string_copyn(s + 4, endptr - s - 4);
1013 s = endptr;
1014 while (isspace(*s)) s++;
1015 }
1016
1017 /* For "set", we are now positioned for the data. For the others, only
1018 "endpass" has no data */
1019
1020 if (c != ACLC_ENDPASS)
1021 {
1022 if (*s++ != '=')
1023 {
1024 *error = string_sprintf("\"=\" missing after ACL \"%s\" %s", name,
1025 cond_modifiers[c]? US"modifier" : US"condition");
1026 return NULL;
1027 }
1028 while (isspace(*s)) s++;
1029 cond->arg = string_copy(s);
1030 }
1031 }
1032
1033 return yield;
1034 }
1035
1036
1037
1038 /*************************************************
1039 * Set up added header line(s) *
1040 *************************************************/
1041
1042 /* This function is called by the add_header modifier, and also from acl_warn()
1043 to implement the now-deprecated way of adding header lines using "message" on a
1044 "warn" verb. The argument is treated as a sequence of header lines which are
1045 added to a chain, provided there isn't an identical one already there.
1046
1047 Argument: string of header lines
1048 Returns: nothing
1049 */
1050
1051 static void
1052 setup_header(uschar *hstring)
1053 {
1054 uschar *p, *q;
1055 int hlen = Ustrlen(hstring);
1056
1057 /* Ignore any leading newlines */
1058 while (*hstring == '\n') hstring++, hlen--;
1059
1060 /* An empty string does nothing; ensure exactly one final newline. */
1061 if (hlen <= 0) return;
1062 if (hstring[--hlen] != '\n') hstring = string_sprintf("%s\n", hstring);
1063 else while(hstring[--hlen] == '\n') hstring[hlen+1] = '\0';
1064
1065 /* Loop for multiple header lines, taking care about continuations */
1066
1067 for (p = q = hstring; *p != 0; )
1068 {
1069 uschar *s;
1070 int newtype = htype_add_bot;
1071 header_line **hptr = &acl_added_headers;
1072
1073 /* Find next header line within the string */
1074
1075 for (;;)
1076 {
1077 q = Ustrchr(q, '\n');
1078 if (*(++q) != ' ' && *q != '\t') break;
1079 }
1080
1081 /* If the line starts with a colon, interpret the instruction for where to
1082 add it. This temporarily sets up a new type. */
1083
1084 if (*p == ':')
1085 {
1086 if (strncmpic(p, US":after_received:", 16) == 0)
1087 {
1088 newtype = htype_add_rec;
1089 p += 16;
1090 }
1091 else if (strncmpic(p, US":at_start_rfc:", 14) == 0)
1092 {
1093 newtype = htype_add_rfc;
1094 p += 14;
1095 }
1096 else if (strncmpic(p, US":at_start:", 10) == 0)
1097 {
1098 newtype = htype_add_top;
1099 p += 10;
1100 }
1101 else if (strncmpic(p, US":at_end:", 8) == 0)
1102 {
1103 newtype = htype_add_bot;
1104 p += 8;
1105 }
1106 while (*p == ' ' || *p == '\t') p++;
1107 }
1108
1109 /* See if this line starts with a header name, and if not, add X-ACL-Warn:
1110 to the front of it. */
1111
1112 for (s = p; s < q - 1; s++)
1113 {
1114 if (*s == ':' || !isgraph(*s)) break;
1115 }
1116
1117 s = string_sprintf("%s%.*s", (*s == ':')? "" : "X-ACL-Warn: ", (int) (q - p), p);
1118 hlen = Ustrlen(s);
1119
1120 /* See if this line has already been added */
1121
1122 while (*hptr != NULL)
1123 {
1124 if (Ustrncmp((*hptr)->text, s, hlen) == 0) break;
1125 hptr = &((*hptr)->next);
1126 }
1127
1128 /* Add if not previously present */
1129
1130 if (*hptr == NULL)
1131 {
1132 header_line *h = store_get(sizeof(header_line));
1133 h->text = s;
1134 h->next = NULL;
1135 h->type = newtype;
1136 h->slen = hlen;
1137 *hptr = h;
1138 hptr = &(h->next);
1139 }
1140
1141 /* Advance for next header line within the string */
1142
1143 p = q;
1144 }
1145 }
1146
1147
1148
1149 /*************************************************
1150 * List the added header lines *
1151 *************************************************/
1152 uschar *
1153 fn_hdrs_added(void)
1154 {
1155 uschar * ret = NULL;
1156 header_line * h = acl_added_headers;
1157 uschar * s;
1158 uschar * cp;
1159 int size = 0;
1160 int ptr = 0;
1161
1162 if (!h) return NULL;
1163
1164 do
1165 {
1166 s = h->text;
1167 while ((cp = Ustrchr(s, '\n')) != NULL)
1168 {
1169 if (cp[1] == '\0') break;
1170
1171 /* contains embedded newline; needs doubling */
1172 ret = string_cat(ret, &size, &ptr, s, cp-s+1);
1173 ret = string_cat(ret, &size, &ptr, US"\n", 1);
1174 s = cp+1;
1175 }
1176 /* last bit of header */
1177
1178 ret = string_cat(ret, &size, &ptr, s, cp-s+1); /* newline-sep list */
1179 }
1180 while((h = h->next));
1181
1182 ret[ptr-1] = '\0'; /* overwrite last newline */
1183 return ret;
1184 }
1185
1186
1187 /*************************************************
1188 * Set up removed header line(s) *
1189 *************************************************/
1190
1191 /* This function is called by the remove_header modifier. The argument is
1192 treated as a sequence of header names which are added to a colon separated
1193 list, provided there isn't an identical one already there.
1194
1195 Argument: string of header names
1196 Returns: nothing
1197 */
1198
1199 static void
1200 setup_remove_header(uschar *hnames)
1201 {
1202 if (*hnames != 0)
1203 {
1204 if (acl_removed_headers == NULL)
1205 acl_removed_headers = hnames;
1206 else
1207 acl_removed_headers = string_sprintf("%s : %s", acl_removed_headers, hnames);
1208 }
1209 }
1210
1211
1212
1213 /*************************************************
1214 * Handle warnings *
1215 *************************************************/
1216
1217 /* This function is called when a WARN verb's conditions are true. It adds to
1218 the message's headers, and/or writes information to the log. In each case, this
1219 only happens once (per message for headers, per connection for log).
1220
1221 ** NOTE: The header adding action using the "message" setting is historic, and
1222 its use is now deprecated. The new add_header modifier should be used instead.
1223
1224 Arguments:
1225 where ACL_WHERE_xxxx indicating which ACL this is
1226 user_message message for adding to headers
1227 log_message message for logging, if different
1228
1229 Returns: nothing
1230 */
1231
1232 static void
1233 acl_warn(int where, uschar *user_message, uschar *log_message)
1234 {
1235 if (log_message != NULL && log_message != user_message)
1236 {
1237 uschar *text;
1238 string_item *logged;
1239
1240 text = string_sprintf("%s Warning: %s", host_and_ident(TRUE),
1241 string_printing(log_message));
1242
1243 /* If a sender verification has failed, and the log message is "sender verify
1244 failed", add the failure message. */
1245
1246 if (sender_verified_failed != NULL &&
1247 sender_verified_failed->message != NULL &&
1248 strcmpic(log_message, US"sender verify failed") == 0)
1249 text = string_sprintf("%s: %s", text, sender_verified_failed->message);
1250
1251 /* Search previously logged warnings. They are kept in malloc
1252 store so they can be freed at the start of a new message. */
1253
1254 for (logged = acl_warn_logged; logged != NULL; logged = logged->next)
1255 if (Ustrcmp(logged->text, text) == 0) break;
1256
1257 if (logged == NULL)
1258 {
1259 int length = Ustrlen(text) + 1;
1260 log_write(0, LOG_MAIN, "%s", text);
1261 logged = store_malloc(sizeof(string_item) + length);
1262 logged->text = (uschar *)logged + sizeof(string_item);
1263 memcpy(logged->text, text, length);
1264 logged->next = acl_warn_logged;
1265 acl_warn_logged = logged;
1266 }
1267 }
1268
1269 /* If there's no user message, we are done. */
1270
1271 if (user_message == NULL) return;
1272
1273 /* If this isn't a message ACL, we can't do anything with a user message.
1274 Log an error. */
1275
1276 if (where > ACL_WHERE_NOTSMTP)
1277 {
1278 log_write(0, LOG_MAIN|LOG_PANIC, "ACL \"warn\" with \"message\" setting "
1279 "found in a non-message (%s) ACL: cannot specify header lines here: "
1280 "message ignored", acl_wherenames[where]);
1281 return;
1282 }
1283
1284 /* The code for setting up header lines is now abstracted into a separate
1285 function so that it can be used for the add_header modifier as well. */
1286
1287 setup_header(user_message);
1288 }
1289
1290
1291
1292 /*************************************************
1293 * Verify and check reverse DNS *
1294 *************************************************/
1295
1296 /* Called from acl_verify() below. We look up the host name(s) of the client IP
1297 address if this has not yet been done. The host_name_lookup() function checks
1298 that one of these names resolves to an address list that contains the client IP
1299 address, so we don't actually have to do the check here.
1300
1301 Arguments:
1302 user_msgptr pointer for user message
1303 log_msgptr pointer for log message
1304
1305 Returns: OK verification condition succeeded
1306 FAIL verification failed
1307 DEFER there was a problem verifying
1308 */
1309
1310 static int
1311 acl_verify_reverse(uschar **user_msgptr, uschar **log_msgptr)
1312 {
1313 int rc;
1314
1315 user_msgptr = user_msgptr; /* stop compiler warning */
1316
1317 /* Previous success */
1318
1319 if (sender_host_name != NULL) return OK;
1320
1321 /* Previous failure */
1322
1323 if (host_lookup_failed)
1324 {
1325 *log_msgptr = string_sprintf("host lookup failed%s", host_lookup_msg);
1326 return FAIL;
1327 }
1328
1329 /* Need to do a lookup */
1330
1331 HDEBUG(D_acl)
1332 debug_printf("looking up host name to force name/address consistency check\n");
1333
1334 if ((rc = host_name_lookup()) != OK)
1335 {
1336 *log_msgptr = (rc == DEFER)?
1337 US"host lookup deferred for reverse lookup check"
1338 :
1339 string_sprintf("host lookup failed for reverse lookup check%s",
1340 host_lookup_msg);
1341 return rc; /* DEFER or FAIL */
1342 }
1343
1344 host_build_sender_fullhost();
1345 return OK;
1346 }
1347
1348
1349
1350 /*************************************************
1351 * Check client IP address matches CSA target *
1352 *************************************************/
1353
1354 /* Called from acl_verify_csa() below. This routine scans a section of a DNS
1355 response for address records belonging to the CSA target hostname. The section
1356 is specified by the reset argument, either RESET_ADDITIONAL or RESET_ANSWERS.
1357 If one of the addresses matches the client's IP address, then the client is
1358 authorized by CSA. If there are target IP addresses but none of them match
1359 then the client is using an unauthorized IP address. If there are no target IP
1360 addresses then the client cannot be using an authorized IP address. (This is
1361 an odd configuration - why didn't the SRV record have a weight of 1 instead?)
1362
1363 Arguments:
1364 dnsa the DNS answer block
1365 dnss a DNS scan block for us to use
1366 reset option specifing what portion to scan, as described above
1367 target the target hostname to use for matching RR names
1368
1369 Returns: CSA_OK successfully authorized
1370 CSA_FAIL_MISMATCH addresses found but none matched
1371 CSA_FAIL_NOADDR no target addresses found
1372 */
1373
1374 static int
1375 acl_verify_csa_address(dns_answer *dnsa, dns_scan *dnss, int reset,
1376 uschar *target)
1377 {
1378 dns_record *rr;
1379 dns_address *da;
1380
1381 BOOL target_found = FALSE;
1382
1383 for (rr = dns_next_rr(dnsa, dnss, reset);
1384 rr != NULL;
1385 rr = dns_next_rr(dnsa, dnss, RESET_NEXT))
1386 {
1387 /* Check this is an address RR for the target hostname. */
1388
1389 if (rr->type != T_A
1390 #if HAVE_IPV6
1391 && rr->type != T_AAAA
1392 #ifdef SUPPORT_A6
1393 && rr->type != T_A6
1394 #endif
1395 #endif
1396 ) continue;
1397
1398 if (strcmpic(target, rr->name) != 0) continue;
1399
1400 target_found = TRUE;
1401
1402 /* Turn the target address RR into a list of textual IP addresses and scan
1403 the list. There may be more than one if it is an A6 RR. */
1404
1405 for (da = dns_address_from_rr(dnsa, rr); da != NULL; da = da->next)
1406 {
1407 /* If the client IP address matches the target IP address, it's good! */
1408
1409 DEBUG(D_acl) debug_printf("CSA target address is %s\n", da->address);
1410
1411 if (strcmpic(sender_host_address, da->address) == 0) return CSA_OK;
1412 }
1413 }
1414
1415 /* If we found some target addresses but none of them matched, the client is
1416 using an unauthorized IP address, otherwise the target has no authorized IP
1417 addresses. */
1418
1419 if (target_found) return CSA_FAIL_MISMATCH;
1420 else return CSA_FAIL_NOADDR;
1421 }
1422
1423
1424
1425 /*************************************************
1426 * Verify Client SMTP Authorization *
1427 *************************************************/
1428
1429 /* Called from acl_verify() below. This routine calls dns_lookup_special()
1430 to find the CSA SRV record corresponding to the domain argument, or
1431 $sender_helo_name if no argument is provided. It then checks that the
1432 client is authorized, and that its IP address corresponds to the SRV
1433 target's address by calling acl_verify_csa_address() above. The address
1434 should have been returned in the DNS response's ADDITIONAL section, but if
1435 not we perform another DNS lookup to get it.
1436
1437 Arguments:
1438 domain pointer to optional parameter following verify = csa
1439
1440 Returns: CSA_UNKNOWN no valid CSA record found
1441 CSA_OK successfully authorized
1442 CSA_FAIL_* client is definitely not authorized
1443 CSA_DEFER_* there was a DNS problem
1444 */
1445
1446 static int
1447 acl_verify_csa(uschar *domain)
1448 {
1449 tree_node *t;
1450 uschar *found, *p;
1451 int priority, weight, port;
1452 dns_answer dnsa;
1453 dns_scan dnss;
1454 dns_record *rr;
1455 int rc, type;
1456 uschar target[256];
1457
1458 /* Work out the domain we are using for the CSA lookup. The default is the
1459 client's HELO domain. If the client has not said HELO, use its IP address
1460 instead. If it's a local client (exim -bs), CSA isn't applicable. */
1461
1462 while (isspace(*domain) && *domain != '\0') ++domain;
1463 if (*domain == '\0') domain = sender_helo_name;
1464 if (domain == NULL) domain = sender_host_address;
1465 if (sender_host_address == NULL) return CSA_UNKNOWN;
1466
1467 /* If we have an address literal, strip off the framing ready for turning it
1468 into a domain. The framing consists of matched square brackets possibly
1469 containing a keyword and a colon before the actual IP address. */
1470
1471 if (domain[0] == '[')
1472 {
1473 uschar *start = Ustrchr(domain, ':');
1474 if (start == NULL) start = domain;
1475 domain = string_copyn(start + 1, Ustrlen(start) - 2);
1476 }
1477
1478 /* Turn domains that look like bare IP addresses into domains in the reverse
1479 DNS. This code also deals with address literals and $sender_host_address. It's
1480 not quite kosher to treat bare domains such as EHLO 192.0.2.57 the same as
1481 address literals, but it's probably the most friendly thing to do. This is an
1482 extension to CSA, so we allow it to be turned off for proper conformance. */
1483
1484 if (string_is_ip_address(domain, NULL) != 0)
1485 {
1486 if (!dns_csa_use_reverse) return CSA_UNKNOWN;
1487 dns_build_reverse(domain, target);
1488 domain = target;
1489 }
1490
1491 /* Find out if we've already done the CSA check for this domain. If we have,
1492 return the same result again. Otherwise build a new cached result structure
1493 for this domain. The name is filled in now, and the value is filled in when
1494 we return from this function. */
1495
1496 t = tree_search(csa_cache, domain);
1497 if (t != NULL) return t->data.val;
1498
1499 t = store_get_perm(sizeof(tree_node) + Ustrlen(domain));
1500 Ustrcpy(t->name, domain);
1501 (void)tree_insertnode(&csa_cache, t);
1502
1503 /* Now we are ready to do the actual DNS lookup(s). */
1504
1505 found = domain;
1506 switch (dns_special_lookup(&dnsa, domain, T_CSA, &found))
1507 {
1508 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1509
1510 default:
1511 return t->data.val = CSA_DEFER_SRV;
1512
1513 /* If we found nothing, the client's authorization is unknown. */
1514
1515 case DNS_NOMATCH:
1516 case DNS_NODATA:
1517 return t->data.val = CSA_UNKNOWN;
1518
1519 /* We got something! Go on to look at the reply in more detail. */
1520
1521 case DNS_SUCCEED:
1522 break;
1523 }
1524
1525 /* Scan the reply for well-formed CSA SRV records. */
1526
1527 for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS);
1528 rr != NULL;
1529 rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT))
1530 {
1531 if (rr->type != T_SRV) continue;
1532
1533 /* Extract the numerical SRV fields (p is incremented) */
1534
1535 p = rr->data;
1536 GETSHORT(priority, p);
1537 GETSHORT(weight, p);
1538 GETSHORT(port, p);
1539
1540 DEBUG(D_acl)
1541 debug_printf("CSA priority=%d weight=%d port=%d\n", priority, weight, port);
1542
1543 /* Check the CSA version number */
1544
1545 if (priority != 1) continue;
1546
1547 /* If the domain does not have a CSA SRV record of its own (i.e. the domain
1548 found by dns_special_lookup() is a parent of the one we asked for), we check
1549 the subdomain assertions in the port field. At the moment there's only one
1550 assertion: legitimate SMTP clients are all explicitly authorized with CSA
1551 SRV records of their own. */
1552
1553 if (found != domain)
1554 {
1555 if (port & 1)
1556 return t->data.val = CSA_FAIL_EXPLICIT;
1557 else
1558 return t->data.val = CSA_UNKNOWN;
1559 }
1560
1561 /* This CSA SRV record refers directly to our domain, so we check the value
1562 in the weight field to work out the domain's authorization. 0 and 1 are
1563 unauthorized; 3 means the client is authorized but we can't check the IP
1564 address in order to authenticate it, so we treat it as unknown; values
1565 greater than 3 are undefined. */
1566
1567 if (weight < 2) return t->data.val = CSA_FAIL_DOMAIN;
1568
1569 if (weight > 2) continue;
1570
1571 /* Weight == 2, which means the domain is authorized. We must check that the
1572 client's IP address is listed as one of the SRV target addresses. Save the
1573 target hostname then break to scan the additional data for its addresses. */
1574
1575 (void)dn_expand(dnsa.answer, dnsa.answer + dnsa.answerlen, p,
1576 (DN_EXPAND_ARG4_TYPE)target, sizeof(target));
1577
1578 DEBUG(D_acl) debug_printf("CSA target is %s\n", target);
1579
1580 break;
1581 }
1582
1583 /* If we didn't break the loop then no appropriate records were found. */
1584
1585 if (rr == NULL) return t->data.val = CSA_UNKNOWN;
1586
1587 /* Do not check addresses if the target is ".", in accordance with RFC 2782.
1588 A target of "." indicates there are no valid addresses, so the client cannot
1589 be authorized. (This is an odd configuration because weight=2 target=. is
1590 equivalent to weight=1, but we check for it in order to keep load off the
1591 root name servers.) Note that dn_expand() turns "." into "". */
1592
1593 if (Ustrcmp(target, "") == 0) return t->data.val = CSA_FAIL_NOADDR;
1594
1595 /* Scan the additional section of the CSA SRV reply for addresses belonging
1596 to the target. If the name server didn't return any additional data (e.g.
1597 because it does not fully support SRV records), we need to do another lookup
1598 to obtain the target addresses; otherwise we have a definitive result. */
1599
1600 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ADDITIONAL, target);
1601 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1602
1603 /* The DNS lookup type corresponds to the IP version used by the client. */
1604
1605 #if HAVE_IPV6
1606 if (Ustrchr(sender_host_address, ':') != NULL)
1607 type = T_AAAA;
1608 else
1609 #endif /* HAVE_IPV6 */
1610 type = T_A;
1611
1612
1613 #if HAVE_IPV6 && defined(SUPPORT_A6)
1614 DNS_LOOKUP_AGAIN:
1615 #endif
1616
1617 switch (dns_lookup(&dnsa, target, type, NULL))
1618 {
1619 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1620
1621 default:
1622 return t->data.val = CSA_DEFER_ADDR;
1623
1624 /* If the query succeeded, scan the addresses and return the result. */
1625
1626 case DNS_SUCCEED:
1627 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ANSWERS, target);
1628 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1629 /* else fall through */
1630
1631 /* If the target has no IP addresses, the client cannot have an authorized
1632 IP address. However, if the target site uses A6 records (not AAAA records)
1633 we have to do yet another lookup in order to check them. */
1634
1635 case DNS_NOMATCH:
1636 case DNS_NODATA:
1637
1638 #if HAVE_IPV6 && defined(SUPPORT_A6)
1639 if (type == T_AAAA) { type = T_A6; goto DNS_LOOKUP_AGAIN; }
1640 #endif
1641
1642 return t->data.val = CSA_FAIL_NOADDR;
1643 }
1644 }
1645
1646
1647
1648 /*************************************************
1649 * Handle verification (address & other) *
1650 *************************************************/
1651
1652 enum { VERIFY_REV_HOST_LKUP, VERIFY_CERT, VERIFY_HELO, VERIFY_CSA, VERIFY_HDR_SYNTAX,
1653 VERIFY_NOT_BLIND, VERIFY_HDR_SNDR, VERIFY_SNDR, VERIFY_RCPT,
1654 VERIFY_HDR_NAMES_ASCII
1655 };
1656 typedef struct {
1657 uschar * name;
1658 int value;
1659 unsigned where_allowed; /* bitmap */
1660 BOOL no_options; /* Never has /option(s) following */
1661 unsigned alt_opt_sep; /* >0 Non-/ option separator (custom parser) */
1662 } verify_type_t;
1663 static verify_type_t verify_type_list[] = {
1664 { US"reverse_host_lookup", VERIFY_REV_HOST_LKUP, ~0, TRUE, 0 },
1665 { US"certificate", VERIFY_CERT, ~0, TRUE, 0 },
1666 { US"helo", VERIFY_HELO, ~0, TRUE, 0 },
1667 { US"csa", VERIFY_CSA, ~0, FALSE, 0 },
1668 { US"header_syntax", VERIFY_HDR_SYNTAX, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), TRUE, 0 },
1669 { US"not_blind", VERIFY_NOT_BLIND, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), TRUE, 0 },
1670 { US"header_sender", VERIFY_HDR_SNDR, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), FALSE, 0 },
1671 { US"sender", VERIFY_SNDR, (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)
1672 |(1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP),
1673 FALSE, 6 },
1674 { US"recipient", VERIFY_RCPT, (1<<ACL_WHERE_RCPT), FALSE, 0 },
1675 { US"header_names_ascii", VERIFY_HDR_NAMES_ASCII, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), TRUE, 0 }
1676 };
1677
1678
1679 enum { CALLOUT_DEFER_OK, CALLOUT_NOCACHE, CALLOUT_RANDOM, CALLOUT_USE_SENDER,
1680 CALLOUT_USE_POSTMASTER, CALLOUT_POSTMASTER, CALLOUT_FULLPOSTMASTER,
1681 CALLOUT_MAILFROM, CALLOUT_POSTMASTER_MAILFROM, CALLOUT_MAXWAIT, CALLOUT_CONNECT,
1682 CALLOUT_TIME
1683 };
1684 typedef struct {
1685 uschar * name;
1686 int value;
1687 int flag;
1688 BOOL has_option; /* Has =option(s) following */
1689 BOOL timeval; /* Has a time value */
1690 } callout_opt_t;
1691 static callout_opt_t callout_opt_list[] = {
1692 { US"defer_ok", CALLOUT_DEFER_OK, 0, FALSE, FALSE },
1693 { US"no_cache", CALLOUT_NOCACHE, vopt_callout_no_cache, FALSE, FALSE },
1694 { US"random", CALLOUT_RANDOM, vopt_callout_random, FALSE, FALSE },
1695 { US"use_sender", CALLOUT_USE_SENDER, vopt_callout_recipsender, FALSE, FALSE },
1696 { US"use_postmaster", CALLOUT_USE_POSTMASTER,vopt_callout_recippmaster, FALSE, FALSE },
1697 { US"postmaster_mailfrom",CALLOUT_POSTMASTER_MAILFROM,0, TRUE, FALSE },
1698 { US"postmaster", CALLOUT_POSTMASTER, 0, FALSE, FALSE },
1699 { US"fullpostmaster", CALLOUT_FULLPOSTMASTER,vopt_callout_fullpm, FALSE, FALSE },
1700 { US"mailfrom", CALLOUT_MAILFROM, 0, TRUE, FALSE },
1701 { US"maxwait", CALLOUT_MAXWAIT, 0, TRUE, TRUE },
1702 { US"connect", CALLOUT_CONNECT, 0, TRUE, TRUE },
1703 { NULL, CALLOUT_TIME, 0, FALSE, TRUE }
1704 };
1705
1706
1707
1708 /* This function implements the "verify" condition. It is called when
1709 encountered in any ACL, because some tests are almost always permitted. Some
1710 just don't make sense, and always fail (for example, an attempt to test a host
1711 lookup for a non-TCP/IP message). Others are restricted to certain ACLs.
1712
1713 Arguments:
1714 where where called from
1715 addr the recipient address that the ACL is handling, or NULL
1716 arg the argument of "verify"
1717 user_msgptr pointer for user message
1718 log_msgptr pointer for log message
1719 basic_errno where to put verify errno
1720
1721 Returns: OK verification condition succeeded
1722 FAIL verification failed
1723 DEFER there was a problem verifying
1724 ERROR syntax error
1725 */
1726
1727 static int
1728 acl_verify(int where, address_item *addr, uschar *arg,
1729 uschar **user_msgptr, uschar **log_msgptr, int *basic_errno)
1730 {
1731 int sep = '/';
1732 int callout = -1;
1733 int callout_overall = -1;
1734 int callout_connect = -1;
1735 int verify_options = 0;
1736 int rc;
1737 BOOL verify_header_sender = FALSE;
1738 BOOL defer_ok = FALSE;
1739 BOOL callout_defer_ok = FALSE;
1740 BOOL no_details = FALSE;
1741 BOOL success_on_redirect = FALSE;
1742 address_item *sender_vaddr = NULL;
1743 uschar *verify_sender_address = NULL;
1744 uschar *pm_mailfrom = NULL;
1745 uschar *se_mailfrom = NULL;
1746
1747 /* Some of the verify items have slash-separated options; some do not. Diagnose
1748 an error if options are given for items that don't expect them.
1749 */
1750
1751 uschar *slash = Ustrchr(arg, '/');
1752 uschar *list = arg;
1753 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
1754 verify_type_t * vp;
1755
1756 if (ss == NULL) goto BAD_VERIFY;
1757
1758 /* Handle name/address consistency verification in a separate function. */
1759
1760 for (vp= verify_type_list;
1761 (char *)vp < (char *)verify_type_list + sizeof(verify_type_list);
1762 vp++
1763 )
1764 if (vp->alt_opt_sep ? strncmpic(ss, vp->name, vp->alt_opt_sep) == 0
1765 : strcmpic (ss, vp->name) == 0)
1766 break;
1767 if ((char *)vp >= (char *)verify_type_list + sizeof(verify_type_list))
1768 goto BAD_VERIFY;
1769
1770 if (vp->no_options && slash != NULL)
1771 {
1772 *log_msgptr = string_sprintf("unexpected '/' found in \"%s\" "
1773 "(this verify item has no options)", arg);
1774 return ERROR;
1775 }
1776 if (!(vp->where_allowed & (1<<where)))
1777 {
1778 *log_msgptr = string_sprintf("cannot verify %s in ACL for %s", vp->name, acl_wherenames[where]);
1779 return ERROR;
1780 }
1781 switch(vp->value)
1782 {
1783 case VERIFY_REV_HOST_LKUP:
1784 if (sender_host_address == NULL) return OK;
1785 return acl_verify_reverse(user_msgptr, log_msgptr);
1786
1787 case VERIFY_CERT:
1788 /* TLS certificate verification is done at STARTTLS time; here we just
1789 test whether it was successful or not. (This is for optional verification; for
1790 mandatory verification, the connection doesn't last this long.) */
1791
1792 if (tls_in.certificate_verified) return OK;
1793 *user_msgptr = US"no verified certificate";
1794 return FAIL;
1795
1796 case VERIFY_HELO:
1797 /* We can test the result of optional HELO verification that might have
1798 occurred earlier. If not, we can attempt the verification now. */
1799
1800 if (!helo_verified && !helo_verify_failed) smtp_verify_helo();
1801 return helo_verified? OK : FAIL;
1802
1803 case VERIFY_CSA:
1804 /* Do Client SMTP Authorization checks in a separate function, and turn the
1805 result code into user-friendly strings. */
1806
1807 rc = acl_verify_csa(list);
1808 *log_msgptr = *user_msgptr = string_sprintf("client SMTP authorization %s",
1809 csa_reason_string[rc]);
1810 csa_status = csa_status_string[rc];
1811 DEBUG(D_acl) debug_printf("CSA result %s\n", csa_status);
1812 return csa_return_code[rc];
1813
1814 case VERIFY_HDR_SYNTAX:
1815 /* Check that all relevant header lines have the correct syntax. If there is
1816 a syntax error, we return details of the error to the sender if configured to
1817 send out full details. (But a "message" setting on the ACL can override, as
1818 always). */
1819
1820 rc = verify_check_headers(log_msgptr);
1821 if (rc != OK && smtp_return_error_details && *log_msgptr != NULL)
1822 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1823 return rc;
1824
1825 case VERIFY_HDR_NAMES_ASCII:
1826 /* Check that all header names are true 7 bit strings
1827 See RFC 5322, 2.2. and RFC 6532, 3. */
1828
1829 rc = verify_check_header_names_ascii(log_msgptr);
1830 if (rc != OK && smtp_return_error_details && *log_msgptr != NULL)
1831 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1832 return rc;
1833
1834 case VERIFY_NOT_BLIND:
1835 /* Check that no recipient of this message is "blind", that is, every envelope
1836 recipient must be mentioned in either To: or Cc:. */
1837
1838 rc = verify_check_notblind();
1839 if (rc != OK)
1840 {
1841 *log_msgptr = string_sprintf("bcc recipient detected");
1842 if (smtp_return_error_details)
1843 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1844 }
1845 return rc;
1846
1847 /* The remaining verification tests check recipient and sender addresses,
1848 either from the envelope or from the header. There are a number of
1849 slash-separated options that are common to all of them. */
1850
1851 case VERIFY_HDR_SNDR:
1852 verify_header_sender = TRUE;
1853 break;
1854
1855 case VERIFY_SNDR:
1856 /* In the case of a sender, this can optionally be followed by an address to use
1857 in place of the actual sender (rare special-case requirement). */
1858 {
1859 uschar *s = ss + 6;
1860 if (*s == 0)
1861 verify_sender_address = sender_address;
1862 else
1863 {
1864 while (isspace(*s)) s++;
1865 if (*s++ != '=') goto BAD_VERIFY;
1866 while (isspace(*s)) s++;
1867 verify_sender_address = string_copy(s);
1868 }
1869 }
1870 break;
1871
1872 case VERIFY_RCPT:
1873 break;
1874 }
1875
1876
1877
1878 /* Remaining items are optional; they apply to sender and recipient
1879 verification, including "header sender" verification. */
1880
1881 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size))
1882 != NULL)
1883 {
1884 if (strcmpic(ss, US"defer_ok") == 0) defer_ok = TRUE;
1885 else if (strcmpic(ss, US"no_details") == 0) no_details = TRUE;
1886 else if (strcmpic(ss, US"success_on_redirect") == 0) success_on_redirect = TRUE;
1887
1888 /* These two old options are left for backwards compatibility */
1889
1890 else if (strcmpic(ss, US"callout_defer_ok") == 0)
1891 {
1892 callout_defer_ok = TRUE;
1893 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1894 }
1895
1896 else if (strcmpic(ss, US"check_postmaster") == 0)
1897 {
1898 pm_mailfrom = US"";
1899 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1900 }
1901
1902 /* The callout option has a number of sub-options, comma separated */
1903
1904 else if (strncmpic(ss, US"callout", 7) == 0)
1905 {
1906 callout = CALLOUT_TIMEOUT_DEFAULT;
1907 ss += 7;
1908 if (*ss != 0)
1909 {
1910 while (isspace(*ss)) ss++;
1911 if (*ss++ == '=')
1912 {
1913 int optsep = ',';
1914 uschar *opt;
1915 uschar buffer[256];
1916 while (isspace(*ss)) ss++;
1917
1918 while ((opt = string_nextinlist(&ss, &optsep, buffer, sizeof(buffer)))
1919 != NULL)
1920 {
1921 callout_opt_t * op;
1922 double period = 1.0F;
1923
1924 for (op= callout_opt_list; op->name; op++)
1925 if (strncmpic(opt, op->name, Ustrlen(op->name)) == 0)
1926 break;
1927
1928 verify_options |= op->flag;
1929 if (op->has_option)
1930 {
1931 opt += Ustrlen(op->name);
1932 while (isspace(*opt)) opt++;
1933 if (*opt++ != '=')
1934 {
1935 *log_msgptr = string_sprintf("'=' expected after "
1936 "\"%s\" in ACL verify condition \"%s\"", op->name, arg);
1937 return ERROR;
1938 }
1939 while (isspace(*opt)) opt++;
1940 }
1941 if (op->timeval)
1942 {
1943 period = readconf_readtime(opt, 0, FALSE);
1944 if (period < 0)
1945 {
1946 *log_msgptr = string_sprintf("bad time value in ACL condition "
1947 "\"verify %s\"", arg);
1948 return ERROR;
1949 }
1950 }
1951
1952 switch(op->value)
1953 {
1954 case CALLOUT_DEFER_OK: callout_defer_ok = TRUE; break;
1955 case CALLOUT_POSTMASTER: pm_mailfrom = US""; break;
1956 case CALLOUT_FULLPOSTMASTER: pm_mailfrom = US""; break;
1957 case CALLOUT_MAILFROM:
1958 if (!verify_header_sender)
1959 {
1960 *log_msgptr = string_sprintf("\"mailfrom\" is allowed as a "
1961 "callout option only for verify=header_sender (detected in ACL "
1962 "condition \"%s\")", arg);
1963 return ERROR;
1964 }
1965 se_mailfrom = string_copy(opt);
1966 break;
1967 case CALLOUT_POSTMASTER_MAILFROM: pm_mailfrom = string_copy(opt); break;
1968 case CALLOUT_MAXWAIT: callout_overall = period; break;
1969 case CALLOUT_CONNECT: callout_connect = period; break;
1970 case CALLOUT_TIME: callout = period; break;
1971 }
1972 }
1973 }
1974 else
1975 {
1976 *log_msgptr = string_sprintf("'=' expected after \"callout\" in "
1977 "ACL condition \"%s\"", arg);
1978 return ERROR;
1979 }
1980 }
1981 }
1982
1983 /* Option not recognized */
1984
1985 else
1986 {
1987 *log_msgptr = string_sprintf("unknown option \"%s\" in ACL "
1988 "condition \"verify %s\"", ss, arg);
1989 return ERROR;
1990 }
1991 }
1992
1993 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster)) ==
1994 (vopt_callout_recipsender|vopt_callout_recippmaster))
1995 {
1996 *log_msgptr = US"only one of use_sender and use_postmaster can be set "
1997 "for a recipient callout";
1998 return ERROR;
1999 }
2000
2001 /* Handle sender-in-header verification. Default the user message to the log
2002 message if giving out verification details. */
2003
2004 if (verify_header_sender)
2005 {
2006 int verrno;
2007 rc = verify_check_header_address(user_msgptr, log_msgptr, callout,
2008 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, verify_options,
2009 &verrno);
2010 if (rc != OK)
2011 {
2012 *basic_errno = verrno;
2013 if (smtp_return_error_details)
2014 {
2015 if (*user_msgptr == NULL && *log_msgptr != NULL)
2016 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
2017 if (rc == DEFER) acl_temp_details = TRUE;
2018 }
2019 }
2020 }
2021
2022 /* Handle a sender address. The default is to verify *the* sender address, but
2023 optionally a different address can be given, for special requirements. If the
2024 address is empty, we are dealing with a bounce message that has no sender, so
2025 we cannot do any checking. If the real sender address gets rewritten during
2026 verification (e.g. DNS widening), set the flag to stop it being rewritten again
2027 during message reception.
2028
2029 A list of verified "sender" addresses is kept to try to avoid doing to much
2030 work repetitively when there are multiple recipients in a message and they all
2031 require sender verification. However, when callouts are involved, it gets too
2032 complicated because different recipients may require different callout options.
2033 Therefore, we always do a full sender verify when any kind of callout is
2034 specified. Caching elsewhere, for instance in the DNS resolver and in the
2035 callout handling, should ensure that this is not terribly inefficient. */
2036
2037 else if (verify_sender_address != NULL)
2038 {
2039 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster))
2040 != 0)
2041 {
2042 *log_msgptr = US"use_sender or use_postmaster cannot be used for a "
2043 "sender verify callout";
2044 return ERROR;
2045 }
2046
2047 sender_vaddr = verify_checked_sender(verify_sender_address);
2048 if (sender_vaddr != NULL && /* Previously checked */
2049 callout <= 0) /* No callout needed this time */
2050 {
2051 /* If the "routed" flag is set, it means that routing worked before, so
2052 this check can give OK (the saved return code value, if set, belongs to a
2053 callout that was done previously). If the "routed" flag is not set, routing
2054 must have failed, so we use the saved return code. */
2055
2056 if (testflag(sender_vaddr, af_verify_routed)) rc = OK; else
2057 {
2058 rc = sender_vaddr->special_action;
2059 *basic_errno = sender_vaddr->basic_errno;
2060 }
2061 HDEBUG(D_acl) debug_printf("using cached sender verify result\n");
2062 }
2063
2064 /* Do a new verification, and cache the result. The cache is used to avoid
2065 verifying the sender multiple times for multiple RCPTs when callouts are not
2066 specified (see comments above).
2067
2068 The cache is also used on failure to give details in response to the first
2069 RCPT that gets bounced for this reason. However, this can be suppressed by
2070 the no_details option, which sets the flag that says "this detail has already
2071 been sent". The cache normally contains just one address, but there may be
2072 more in esoteric circumstances. */
2073
2074 else
2075 {
2076 BOOL routed = TRUE;
2077 uschar *save_address_data = deliver_address_data;
2078
2079 sender_vaddr = deliver_make_addr(verify_sender_address, TRUE);
2080 if (no_details) setflag(sender_vaddr, af_sverify_told);
2081 if (verify_sender_address[0] != 0)
2082 {
2083 /* If this is the real sender address, save the unrewritten version
2084 for use later in receive. Otherwise, set a flag so that rewriting the
2085 sender in verify_address() does not update sender_address. */
2086
2087 if (verify_sender_address == sender_address)
2088 sender_address_unrewritten = sender_address;
2089 else
2090 verify_options |= vopt_fake_sender;
2091
2092 if (success_on_redirect)
2093 verify_options |= vopt_success_on_redirect;
2094
2095 /* The recipient, qualify, and expn options are never set in
2096 verify_options. */
2097
2098 rc = verify_address(sender_vaddr, NULL, verify_options, callout,
2099 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, &routed);
2100
2101 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
2102
2103 if (rc == OK)
2104 {
2105 if (Ustrcmp(sender_vaddr->address, verify_sender_address) != 0)
2106 {
2107 DEBUG(D_acl) debug_printf("sender %s verified ok as %s\n",
2108 verify_sender_address, sender_vaddr->address);
2109 }
2110 else
2111 {
2112 DEBUG(D_acl) debug_printf("sender %s verified ok\n",
2113 verify_sender_address);
2114 }
2115 }
2116 else *basic_errno = sender_vaddr->basic_errno;
2117 }
2118 else rc = OK; /* Null sender */
2119
2120 /* Cache the result code */
2121
2122 if (routed) setflag(sender_vaddr, af_verify_routed);
2123 if (callout > 0) setflag(sender_vaddr, af_verify_callout);
2124 sender_vaddr->special_action = rc;
2125 sender_vaddr->next = sender_verified_list;
2126 sender_verified_list = sender_vaddr;
2127
2128 /* Restore the recipient address data, which might have been clobbered by
2129 the sender verification. */
2130
2131 deliver_address_data = save_address_data;
2132 }
2133
2134 /* Put the sender address_data value into $sender_address_data */
2135
2136 sender_address_data = sender_vaddr->p.address_data;
2137 }
2138
2139 /* A recipient address just gets a straightforward verify; again we must handle
2140 the DEFER overrides. */
2141
2142 else
2143 {
2144 address_item addr2;
2145
2146 if (success_on_redirect)
2147 verify_options |= vopt_success_on_redirect;
2148
2149 /* We must use a copy of the address for verification, because it might
2150 get rewritten. */
2151
2152 addr2 = *addr;
2153 rc = verify_address(&addr2, NULL, verify_options|vopt_is_recipient, callout,
2154 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, NULL);
2155 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
2156
2157 *basic_errno = addr2.basic_errno;
2158 *log_msgptr = addr2.message;
2159 *user_msgptr = (addr2.user_message != NULL)?
2160 addr2.user_message : addr2.message;
2161
2162 /* Allow details for temporary error if the address is so flagged. */
2163 if (testflag((&addr2), af_pass_message)) acl_temp_details = TRUE;
2164
2165 /* Make $address_data visible */
2166 deliver_address_data = addr2.p.address_data;
2167 }
2168
2169 /* We have a result from the relevant test. Handle defer overrides first. */
2170
2171 if (rc == DEFER && (defer_ok ||
2172 (callout_defer_ok && *basic_errno == ERRNO_CALLOUTDEFER)))
2173 {
2174 HDEBUG(D_acl) debug_printf("verify defer overridden by %s\n",
2175 defer_ok? "defer_ok" : "callout_defer_ok");
2176 rc = OK;
2177 }
2178
2179 /* If we've failed a sender, set up a recipient message, and point
2180 sender_verified_failed to the address item that actually failed. */
2181
2182 if (rc != OK && verify_sender_address != NULL)
2183 {
2184 if (rc != DEFER)
2185 {
2186 *log_msgptr = *user_msgptr = US"Sender verify failed";
2187 }
2188 else if (*basic_errno != ERRNO_CALLOUTDEFER)
2189 {
2190 *log_msgptr = *user_msgptr = US"Could not complete sender verify";
2191 }
2192 else
2193 {
2194 *log_msgptr = US"Could not complete sender verify callout";
2195 *user_msgptr = smtp_return_error_details? sender_vaddr->user_message :
2196 *log_msgptr;
2197 }
2198
2199 sender_verified_failed = sender_vaddr;
2200 }
2201
2202 /* Verifying an address messes up the values of $domain and $local_part,
2203 so reset them before returning if this is a RCPT ACL. */
2204
2205 if (addr != NULL)
2206 {
2207 deliver_domain = addr->domain;
2208 deliver_localpart = addr->local_part;
2209 }
2210 return rc;
2211
2212 /* Syntax errors in the verify argument come here. */
2213
2214 BAD_VERIFY:
2215 *log_msgptr = string_sprintf("expected \"sender[=address]\", \"recipient\", "
2216 "\"helo\", \"header_syntax\", \"header_sender\", \"header_names_ascii\" "
2217 "or \"reverse_host_lookup\" at start of ACL condition "
2218 "\"verify %s\"", arg);
2219 return ERROR;
2220 }
2221
2222
2223
2224
2225 /*************************************************
2226 * Check argument for control= modifier *
2227 *************************************************/
2228
2229 /* Called from acl_check_condition() below
2230
2231 Arguments:
2232 arg the argument string for control=
2233 pptr set to point to the terminating character
2234 where which ACL we are in
2235 log_msgptr for error messages
2236
2237 Returns: CONTROL_xxx value
2238 */
2239
2240 static int
2241 decode_control(uschar *arg, uschar **pptr, int where, uschar **log_msgptr)
2242 {
2243 int len;
2244 control_def *d;
2245
2246 for (d = controls_list;
2247 d < controls_list + sizeof(controls_list)/sizeof(control_def);
2248 d++)
2249 {
2250 len = Ustrlen(d->name);
2251 if (Ustrncmp(d->name, arg, len) == 0) break;
2252 }
2253
2254 if (d >= controls_list + sizeof(controls_list)/sizeof(control_def) ||
2255 (arg[len] != 0 && (!d->has_option || arg[len] != '/')))
2256 {
2257 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
2258 return CONTROL_ERROR;
2259 }
2260
2261 *pptr = arg + len;
2262 return d->value;
2263 }
2264
2265
2266
2267
2268 /*************************************************
2269 * Return a ratelimit error *
2270 *************************************************/
2271
2272 /* Called from acl_ratelimit() below
2273
2274 Arguments:
2275 log_msgptr for error messages
2276 format format string
2277 ... supplementary arguments
2278 ss ratelimit option name
2279 where ACL_WHERE_xxxx indicating which ACL this is
2280
2281 Returns: ERROR
2282 */
2283
2284 static int
2285 ratelimit_error(uschar **log_msgptr, const char *format, ...)
2286 {
2287 va_list ap;
2288 uschar buffer[STRING_SPRINTF_BUFFER_SIZE];
2289 va_start(ap, format);
2290 if (!string_vformat(buffer, sizeof(buffer), format, ap))
2291 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
2292 "string_sprintf expansion was longer than " SIZE_T_FMT, sizeof(buffer));
2293 va_end(ap);
2294 *log_msgptr = string_sprintf(
2295 "error in arguments to \"ratelimit\" condition: %s", buffer);
2296 return ERROR;
2297 }
2298
2299
2300
2301
2302 /*************************************************
2303 * Handle rate limiting *
2304 *************************************************/
2305
2306 /* Called by acl_check_condition() below to calculate the result
2307 of the ACL ratelimit condition.
2308
2309 Note that the return value might be slightly unexpected: if the
2310 sender's rate is above the limit then the result is OK. This is
2311 similar to the dnslists condition, and is so that you can write
2312 ACL clauses like: defer ratelimit = 15 / 1h
2313
2314 Arguments:
2315 arg the option string for ratelimit=
2316 where ACL_WHERE_xxxx indicating which ACL this is
2317 log_msgptr for error messages
2318
2319 Returns: OK - Sender's rate is above limit
2320 FAIL - Sender's rate is below limit
2321 DEFER - Problem opening ratelimit database
2322 ERROR - Syntax error in options.
2323 */
2324
2325 static int
2326 acl_ratelimit(uschar *arg, int where, uschar **log_msgptr)
2327 {
2328 double limit, period, count;
2329 uschar *ss;
2330 uschar *key = NULL;
2331 uschar *unique = NULL;
2332 int sep = '/';
2333 BOOL leaky = FALSE, strict = FALSE, readonly = FALSE;
2334 BOOL noupdate = FALSE, badacl = FALSE;
2335 int mode = RATE_PER_WHAT;
2336 int old_pool, rc;
2337 tree_node **anchor, *t;
2338 open_db dbblock, *dbm;
2339 int dbdb_size;
2340 dbdata_ratelimit *dbd;
2341 dbdata_ratelimit_unique *dbdb;
2342 struct timeval tv;
2343
2344 /* Parse the first two options and record their values in expansion
2345 variables. These variables allow the configuration to have informative
2346 error messages based on rate limits obtained from a table lookup. */
2347
2348 /* First is the maximum number of messages per period / maximum burst
2349 size, which must be greater than or equal to zero. Zero is useful for
2350 rate measurement as opposed to rate limiting. */
2351
2352 sender_rate_limit = string_nextinlist(&arg, &sep, NULL, 0);
2353 if (sender_rate_limit == NULL)
2354 limit = -1.0;
2355 else
2356 {
2357 limit = Ustrtod(sender_rate_limit, &ss);
2358 if (tolower(*ss) == 'k') { limit *= 1024.0; ss++; }
2359 else if (tolower(*ss) == 'm') { limit *= 1024.0*1024.0; ss++; }
2360 else if (tolower(*ss) == 'g') { limit *= 1024.0*1024.0*1024.0; ss++; }
2361 }
2362 if (limit < 0.0 || *ss != '\0')
2363 return ratelimit_error(log_msgptr,
2364 "\"%s\" is not a positive number", sender_rate_limit);
2365
2366 /* Second is the rate measurement period / exponential smoothing time
2367 constant. This must be strictly greater than zero, because zero leads to
2368 run-time division errors. */
2369
2370 sender_rate_period = string_nextinlist(&arg, &sep, NULL, 0);
2371 if (sender_rate_period == NULL) period = -1.0;
2372 else period = readconf_readtime(sender_rate_period, 0, FALSE);
2373 if (period <= 0.0)
2374 return ratelimit_error(log_msgptr,
2375 "\"%s\" is not a time value", sender_rate_period);
2376
2377 /* By default we are counting one of something, but the per_rcpt,
2378 per_byte, and count options can change this. */
2379
2380 count = 1.0;
2381
2382 /* Parse the other options. */
2383
2384 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2385 != NULL)
2386 {
2387 if (strcmpic(ss, US"leaky") == 0) leaky = TRUE;
2388 else if (strcmpic(ss, US"strict") == 0) strict = TRUE;
2389 else if (strcmpic(ss, US"noupdate") == 0) noupdate = TRUE;
2390 else if (strcmpic(ss, US"readonly") == 0) readonly = TRUE;
2391 else if (strcmpic(ss, US"per_cmd") == 0) RATE_SET(mode, PER_CMD);
2392 else if (strcmpic(ss, US"per_conn") == 0)
2393 {
2394 RATE_SET(mode, PER_CONN);
2395 if (where == ACL_WHERE_NOTSMTP || where == ACL_WHERE_NOTSMTP_START)
2396 badacl = TRUE;
2397 }
2398 else if (strcmpic(ss, US"per_mail") == 0)
2399 {
2400 RATE_SET(mode, PER_MAIL);
2401 if (where > ACL_WHERE_NOTSMTP) badacl = TRUE;
2402 }
2403 else if (strcmpic(ss, US"per_rcpt") == 0)
2404 {
2405 /* If we are running in the RCPT ACL, then we'll count the recipients
2406 one by one, but if we are running when we have accumulated the whole
2407 list then we'll add them all in one batch. */
2408 if (where == ACL_WHERE_RCPT)
2409 RATE_SET(mode, PER_RCPT);
2410 else if (where >= ACL_WHERE_PREDATA && where <= ACL_WHERE_NOTSMTP)
2411 RATE_SET(mode, PER_ALLRCPTS), count = (double)recipients_count;
2412 else if (where == ACL_WHERE_MAIL || where > ACL_WHERE_NOTSMTP)
2413 RATE_SET(mode, PER_RCPT), badacl = TRUE;
2414 }
2415 else if (strcmpic(ss, US"per_byte") == 0)
2416 {
2417 /* If we have not yet received the message data and there was no SIZE
2418 declaration on the MAIL comand, then it's safe to just use a value of
2419 zero and let the recorded rate decay as if nothing happened. */
2420 RATE_SET(mode, PER_MAIL);
2421 if (where > ACL_WHERE_NOTSMTP) badacl = TRUE;
2422 else count = message_size < 0 ? 0.0 : (double)message_size;
2423 }
2424 else if (strcmpic(ss, US"per_addr") == 0)
2425 {
2426 RATE_SET(mode, PER_RCPT);
2427 if (where != ACL_WHERE_RCPT) badacl = TRUE, unique = US"*";
2428 else unique = string_sprintf("%s@%s", deliver_localpart, deliver_domain);
2429 }
2430 else if (strncmpic(ss, US"count=", 6) == 0)
2431 {
2432 uschar *e;
2433 count = Ustrtod(ss+6, &e);
2434 if (count < 0.0 || *e != '\0')
2435 return ratelimit_error(log_msgptr,
2436 "\"%s\" is not a positive number", ss);
2437 }
2438 else if (strncmpic(ss, US"unique=", 7) == 0)
2439 unique = string_copy(ss + 7);
2440 else if (key == NULL)
2441 key = string_copy(ss);
2442 else
2443 key = string_sprintf("%s/%s", key, ss);
2444 }
2445
2446 /* Sanity check. When the badacl flag is set the update mode must either
2447 be readonly (which is the default if it is omitted) or, for backwards
2448 compatibility, a combination of noupdate and strict or leaky. */
2449
2450 if (mode == RATE_PER_CLASH)
2451 return ratelimit_error(log_msgptr, "conflicting per_* options");
2452 if (leaky + strict + readonly > 1)
2453 return ratelimit_error(log_msgptr, "conflicting update modes");
2454 if (badacl && (leaky || strict) && !noupdate)
2455 return ratelimit_error(log_msgptr,
2456 "\"%s\" must not have /leaky or /strict option in %s ACL",
2457 ratelimit_option_string[mode], acl_wherenames[where]);
2458
2459 /* Set the default values of any unset options. In readonly mode we
2460 perform the rate computation without any increment so that its value
2461 decays to eventually allow over-limit senders through. */
2462
2463 if (noupdate) readonly = TRUE, leaky = strict = FALSE;
2464 if (badacl) readonly = TRUE;
2465 if (readonly) count = 0.0;
2466 if (!strict && !readonly) leaky = TRUE;
2467 if (mode == RATE_PER_WHAT) mode = RATE_PER_MAIL;
2468
2469 /* Create the lookup key. If there is no explicit key, use sender_host_address.
2470 If there is no sender_host_address (e.g. -bs or acl_not_smtp) then we simply
2471 omit it. The smoothing constant (sender_rate_period) and the per_xxx options
2472 are added to the key because they alter the meaning of the stored data. */
2473
2474 if (key == NULL)
2475 key = (sender_host_address == NULL)? US"" : sender_host_address;
2476
2477 key = string_sprintf("%s/%s/%s%s",
2478 sender_rate_period,
2479 ratelimit_option_string[mode],
2480 unique == NULL ? "" : "unique/",
2481 key);
2482
2483 HDEBUG(D_acl)
2484 debug_printf("ratelimit condition count=%.0f %.1f/%s\n", count, limit, key);
2485
2486 /* See if we have already computed the rate by looking in the relevant tree.
2487 For per-connection rate limiting, store tree nodes and dbdata in the permanent
2488 pool so that they survive across resets. In readonly mode we only remember the
2489 result for the rest of this command in case a later command changes it. After
2490 this bit of logic the code is independent of the per_* mode. */
2491
2492 old_pool = store_pool;
2493
2494 if (readonly)
2495 anchor = &ratelimiters_cmd;
2496 else switch(mode) {
2497 case RATE_PER_CONN:
2498 anchor = &ratelimiters_conn;
2499 store_pool = POOL_PERM;
2500 break;
2501 case RATE_PER_BYTE:
2502 case RATE_PER_MAIL:
2503 case RATE_PER_ALLRCPTS:
2504 anchor = &ratelimiters_mail;
2505 break;
2506 case RATE_PER_ADDR:
2507 case RATE_PER_CMD:
2508 case RATE_PER_RCPT:
2509 anchor = &ratelimiters_cmd;
2510 break;
2511 default:
2512 anchor = NULL; /* silence an "unused" complaint */
2513 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
2514 "internal ACL error: unknown ratelimit mode %d", mode);
2515 break;
2516 }
2517
2518 t = tree_search(*anchor, key);
2519 if (t != NULL)
2520 {
2521 dbd = t->data.ptr;
2522 /* The following few lines duplicate some of the code below. */
2523 rc = (dbd->rate < limit)? FAIL : OK;
2524 store_pool = old_pool;
2525 sender_rate = string_sprintf("%.1f", dbd->rate);
2526 HDEBUG(D_acl)
2527 debug_printf("ratelimit found pre-computed rate %s\n", sender_rate);
2528 return rc;
2529 }
2530
2531 /* We aren't using a pre-computed rate, so get a previously recorded rate
2532 from the database, which will be updated and written back if required. */
2533
2534 dbm = dbfn_open(US"ratelimit", O_RDWR, &dbblock, TRUE);
2535 if (dbm == NULL)
2536 {
2537 store_pool = old_pool;
2538 sender_rate = NULL;
2539 HDEBUG(D_acl) debug_printf("ratelimit database not available\n");
2540 *log_msgptr = US"ratelimit database not available";
2541 return DEFER;
2542 }
2543 dbdb = dbfn_read_with_length(dbm, key, &dbdb_size);
2544 dbd = NULL;
2545
2546 gettimeofday(&tv, NULL);
2547
2548 if (dbdb != NULL)
2549 {
2550 /* Locate the basic ratelimit block inside the DB data. */
2551 HDEBUG(D_acl) debug_printf("ratelimit found key in database\n");
2552 dbd = &dbdb->dbd;
2553
2554 /* Forget the old Bloom filter if it is too old, so that we count each
2555 repeating event once per period. We don't simply clear and re-use the old
2556 filter because we want its size to change if the limit changes. Note that
2557 we keep the dbd pointer for copying the rate into the new data block. */
2558
2559 if(unique != NULL && tv.tv_sec > dbdb->bloom_epoch + period)
2560 {
2561 HDEBUG(D_acl) debug_printf("ratelimit discarding old Bloom filter\n");
2562 dbdb = NULL;
2563 }
2564
2565 /* Sanity check. */
2566
2567 if(unique != NULL && dbdb_size < sizeof(*dbdb))
2568 {
2569 HDEBUG(D_acl) debug_printf("ratelimit discarding undersize Bloom filter\n");
2570 dbdb = NULL;
2571 }
2572 }
2573
2574 /* Allocate a new data block if the database lookup failed
2575 or the Bloom filter passed its age limit. */
2576
2577 if (dbdb == NULL)
2578 {
2579 if (unique == NULL)
2580 {
2581 /* No Bloom filter. This basic ratelimit block is initialized below. */
2582 HDEBUG(D_acl) debug_printf("ratelimit creating new rate data block\n");
2583 dbdb_size = sizeof(*dbd);
2584 dbdb = store_get(dbdb_size);
2585 }
2586 else
2587 {
2588 int extra;
2589 HDEBUG(D_acl) debug_printf("ratelimit creating new Bloom filter\n");
2590
2591 /* See the long comment below for an explanation of the magic number 2.
2592 The filter has a minimum size in case the rate limit is very small;
2593 this is determined by the definition of dbdata_ratelimit_unique. */
2594
2595 extra = (int)limit * 2 - sizeof(dbdb->bloom);
2596 if (extra < 0) extra = 0;
2597 dbdb_size = sizeof(*dbdb) + extra;
2598 dbdb = store_get(dbdb_size);
2599 dbdb->bloom_epoch = tv.tv_sec;
2600 dbdb->bloom_size = sizeof(dbdb->bloom) + extra;
2601 memset(dbdb->bloom, 0, dbdb->bloom_size);
2602
2603 /* Preserve any basic ratelimit data (which is our longer-term memory)
2604 by copying it from the discarded block. */
2605
2606 if (dbd != NULL)
2607 {
2608 dbdb->dbd = *dbd;
2609 dbd = &dbdb->dbd;
2610 }
2611 }
2612 }
2613
2614 /* If we are counting unique events, find out if this event is new or not.
2615 If the client repeats the event during the current period then it should be
2616 counted. We skip this code in readonly mode for efficiency, because any
2617 changes to the filter will be discarded and because count is already set to
2618 zero. */
2619
2620 if (unique != NULL && !readonly)
2621 {
2622 /* We identify unique events using a Bloom filter. (You can find my
2623 notes on Bloom filters at http://fanf.livejournal.com/81696.html)
2624 With the per_addr option, an "event" is a recipient address, though the
2625 user can use the unique option to define their own events. We only count
2626 an event if we have not seen it before.
2627
2628 We size the filter according to the rate limit, which (in leaky mode)
2629 is the limit on the population of the filter. We allow 16 bits of space
2630 per entry (see the construction code above) and we set (up to) 8 of them
2631 when inserting an element (see the loop below). The probability of a false
2632 positive (an event we have not seen before but which we fail to count) is
2633
2634 size = limit * 16
2635 numhash = 8
2636 allzero = exp(-numhash * pop / size)
2637 = exp(-0.5 * pop / limit)
2638 fpr = pow(1 - allzero, numhash)
2639
2640 For senders at the limit the fpr is 0.06% or 1 in 1700
2641 and for senders at half the limit it is 0.0006% or 1 in 170000
2642
2643 In strict mode the Bloom filter can fill up beyond the normal limit, in
2644 which case the false positive rate will rise. This means that the
2645 measured rate for very fast senders can bogusly drop off after a while.
2646
2647 At twice the limit, the fpr is 2.5% or 1 in 40
2648 At four times the limit, it is 31% or 1 in 3.2
2649
2650 It takes ln(pop/limit) periods for an over-limit burst of pop events to
2651 decay below the limit, and if this is more than one then the Bloom filter
2652 will be discarded before the decay gets that far. The false positive rate
2653 at this threshold is 9.3% or 1 in 10.7. */
2654
2655 BOOL seen;
2656 unsigned n, hash, hinc;
2657 uschar md5sum[16];
2658 md5 md5info;
2659
2660 /* Instead of using eight independent hash values, we combine two values
2661 using the formula h1 + n * h2. This does not harm the Bloom filter's
2662 performance, and means the amount of hash we need is independent of the
2663 number of bits we set in the filter. */
2664
2665 md5_start(&md5info);
2666 md5_end(&md5info, unique, Ustrlen(unique), md5sum);
2667 hash = md5sum[0] | md5sum[1] << 8 | md5sum[2] << 16 | md5sum[3] << 24;
2668 hinc = md5sum[4] | md5sum[5] << 8 | md5sum[6] << 16 | md5sum[7] << 24;
2669
2670 /* Scan the bits corresponding to this event. A zero bit means we have
2671 not seen it before. Ensure all bits are set to record this event. */
2672
2673 HDEBUG(D_acl) debug_printf("ratelimit checking uniqueness of %s\n", unique);
2674
2675 seen = TRUE;
2676 for (n = 0; n < 8; n++, hash += hinc)
2677 {
2678 int bit = 1 << (hash % 8);
2679 int byte = (hash / 8) % dbdb->bloom_size;
2680 if ((dbdb->bloom[byte] & bit) == 0)
2681 {
2682 dbdb->bloom[byte] |= bit;
2683 seen = FALSE;
2684 }
2685 }
2686
2687 /* If this event has occurred before, do not count it. */
2688
2689 if (seen)
2690 {
2691 HDEBUG(D_acl) debug_printf("ratelimit event found in Bloom filter\n");
2692 count = 0.0;
2693 }
2694 else
2695 HDEBUG(D_acl) debug_printf("ratelimit event added to Bloom filter\n");
2696 }
2697
2698 /* If there was no previous ratelimit data block for this key, initialize
2699 the new one, otherwise update the block from the database. The initial rate
2700 is what would be computed by the code below for an infinite interval. */
2701
2702 if (dbd == NULL)
2703 {
2704 HDEBUG(D_acl) debug_printf("ratelimit initializing new key's rate data\n");
2705 dbd = &dbdb->dbd;
2706 dbd->time_stamp = tv.tv_sec;
2707 dbd->time_usec = tv.tv_usec;
2708 dbd->rate = count;
2709 }
2710 else
2711 {
2712 /* The smoothed rate is computed using an exponentially weighted moving
2713 average adjusted for variable sampling intervals. The standard EWMA for
2714 a fixed sampling interval is: f'(t) = (1 - a) * f(t) + a * f'(t - 1)
2715 where f() is the measured value and f'() is the smoothed value.
2716
2717 Old data decays out of the smoothed value exponentially, such that data n
2718 samples old is multiplied by a^n. The exponential decay time constant p
2719 is defined such that data p samples old is multiplied by 1/e, which means
2720 that a = exp(-1/p). We can maintain the same time constant for a variable
2721 sampling interval i by using a = exp(-i/p).
2722
2723 The rate we are measuring is messages per period, suitable for directly
2724 comparing with the limit. The average rate between now and the previous
2725 message is period / interval, which we feed into the EWMA as the sample.
2726
2727 It turns out that the number of messages required for the smoothed rate
2728 to reach the limit when they are sent in a burst is equal to the limit.
2729 This can be seen by analysing the value of the smoothed rate after N
2730 messages sent at even intervals. Let k = (1 - a) * p/i
2731
2732 rate_1 = (1 - a) * p/i + a * rate_0
2733 = k + a * rate_0
2734 rate_2 = k + a * rate_1
2735 = k + a * k + a^2 * rate_0
2736 rate_3 = k + a * k + a^2 * k + a^3 * rate_0
2737 rate_N = rate_0 * a^N + k * SUM(x=0..N-1)(a^x)
2738 = rate_0 * a^N + k * (1 - a^N) / (1 - a)
2739 = rate_0 * a^N + p/i * (1 - a^N)
2740
2741 When N is large, a^N -> 0 so rate_N -> p/i as desired.
2742
2743 rate_N = p/i + (rate_0 - p/i) * a^N
2744 a^N = (rate_N - p/i) / (rate_0 - p/i)
2745 N * -i/p = log((rate_N - p/i) / (rate_0 - p/i))
2746 N = p/i * log((rate_0 - p/i) / (rate_N - p/i))
2747
2748 Numerical analysis of the above equation, setting the computed rate to
2749 increase from rate_0 = 0 to rate_N = limit, shows that for large sending
2750 rates, p/i, the number of messages N = limit. So limit serves as both the
2751 maximum rate measured in messages per period, and the maximum number of
2752 messages that can be sent in a fast burst. */
2753
2754 double this_time = (double)tv.tv_sec
2755 + (double)tv.tv_usec / 1000000.0;
2756 double prev_time = (double)dbd->time_stamp
2757 + (double)dbd->time_usec / 1000000.0;
2758
2759 /* We must avoid division by zero, and deal gracefully with the clock going
2760 backwards. If we blunder ahead when time is in reverse then the computed
2761 rate will be bogus. To be safe we clamp interval to a very small number. */
2762
2763 double interval = this_time - prev_time <= 0.0 ? 1e-9
2764 : this_time - prev_time;
2765
2766 double i_over_p = interval / period;
2767 double a = exp(-i_over_p);
2768
2769 /* Combine the instantaneous rate (period / interval) with the previous rate
2770 using the smoothing factor a. In order to measure sized events, multiply the
2771 instantaneous rate by the count of bytes or recipients etc. */
2772
2773 dbd->time_stamp = tv.tv_sec;
2774 dbd->time_usec = tv.tv_usec;
2775 dbd->rate = (1 - a) * count / i_over_p + a * dbd->rate;
2776
2777 /* When events are very widely spaced the computed rate tends towards zero.
2778 Although this is accurate it turns out not to be useful for our purposes,
2779 especially when the first event after a long silence is the start of a spam
2780 run. A more useful model is that the rate for an isolated event should be the
2781 size of the event per the period size, ignoring the lack of events outside
2782 the current period and regardless of where the event falls in the period. So,
2783 if the interval was so long that the calculated rate is unhelpfully small, we
2784 re-intialize the rate. In the absence of higher-rate bursts, the condition
2785 below is true if the interval is greater than the period. */
2786
2787 if (dbd->rate < count) dbd->rate = count;
2788 }
2789
2790 /* Clients sending at the limit are considered to be over the limit.
2791 This matters for edge cases such as a limit of zero, when the client
2792 should be completely blocked. */
2793
2794 rc = (dbd->rate < limit)? FAIL : OK;
2795
2796 /* Update the state if the rate is low or if we are being strict. If we
2797 are in leaky mode and the sender's rate is too high, we do not update
2798 the recorded rate in order to avoid an over-aggressive sender's retry
2799 rate preventing them from getting any email through. If readonly is set,
2800 neither leaky nor strict are set, so we do not do any updates. */
2801
2802 if ((rc == FAIL && leaky) || strict)
2803 {
2804 dbfn_write(dbm, key, dbdb, dbdb_size);
2805 HDEBUG(D_acl) debug_printf("ratelimit db updated\n");
2806 }
2807 else
2808 {
2809 HDEBUG(D_acl) debug_printf("ratelimit db not updated: %s\n",
2810 readonly? "readonly mode" : "over the limit, but leaky");
2811 }
2812
2813 dbfn_close(dbm);
2814
2815 /* Store the result in the tree for future reference. */
2816
2817 t = store_get(sizeof(tree_node) + Ustrlen(key));
2818 t->data.ptr = dbd;
2819 Ustrcpy(t->name, key);
2820 (void)tree_insertnode(anchor, t);
2821
2822 /* We create the formatted version of the sender's rate very late in
2823 order to ensure that it is done using the correct storage pool. */
2824
2825 store_pool = old_pool;
2826 sender_rate = string_sprintf("%.1f", dbd->rate);
2827
2828 HDEBUG(D_acl)
2829 debug_printf("ratelimit computed rate %s\n", sender_rate);
2830
2831 return rc;
2832 }
2833
2834
2835
2836 /*************************************************
2837 * The udpsend ACL modifier *
2838 *************************************************/
2839
2840 /* Called by acl_check_condition() below.
2841
2842 Arguments:
2843 arg the option string for udpsend=
2844 log_msgptr for error messages
2845
2846 Returns: OK - Completed.
2847 DEFER - Problem with DNS lookup.
2848 ERROR - Syntax error in options.
2849 */
2850
2851 static int
2852 acl_udpsend(uschar *arg, uschar **log_msgptr)
2853 {
2854 int sep = 0;
2855 uschar *hostname;
2856 uschar *portstr;
2857 uschar *portend;
2858 host_item *h;
2859 int portnum;
2860 int len;
2861 int r, s;
2862 uschar * errstr;
2863
2864 hostname = string_nextinlist(&arg, &sep, NULL, 0);
2865 portstr = string_nextinlist(&arg, &sep, NULL, 0);
2866
2867 if (hostname == NULL)
2868 {
2869 *log_msgptr = US"missing destination host in \"udpsend\" modifier";
2870 return ERROR;
2871 }
2872 if (portstr == NULL)
2873 {
2874 *log_msgptr = US"missing destination port in \"udpsend\" modifier";
2875 return ERROR;
2876 }
2877 if (arg == NULL)
2878 {
2879 *log_msgptr = US"missing datagram payload in \"udpsend\" modifier";
2880 return ERROR;
2881 }
2882 portnum = Ustrtol(portstr, &portend, 10);
2883 if (*portend != '\0')
2884 {
2885 *log_msgptr = US"bad destination port in \"udpsend\" modifier";
2886 return ERROR;
2887 }
2888
2889 /* Make a single-item host list. */
2890 h = store_get(sizeof(host_item));
2891 memset(h, 0, sizeof(host_item));
2892 h->name = hostname;
2893 h->port = portnum;
2894 h->mx = MX_NONE;
2895
2896 if (string_is_ip_address(hostname, NULL))
2897 h->address = hostname, r = HOST_FOUND;
2898 else
2899 r = host_find_byname(h, NULL, 0, NULL, FALSE);
2900 if (r == HOST_FIND_FAILED || r == HOST_FIND_AGAIN)
2901 {
2902 *log_msgptr = US"DNS lookup failed in \"udpsend\" modifier";
2903 return DEFER;
2904 }
2905
2906 HDEBUG(D_acl)
2907 debug_printf("udpsend [%s]:%d %s\n", h->address, portnum, arg);
2908
2909 r = s = ip_connectedsocket(SOCK_DGRAM, h->address, portnum, portnum,
2910 1, NULL, &errstr);
2911 if (r < 0) goto defer;
2912 len = Ustrlen(arg);
2913 r = send(s, arg, len, 0);
2914 if (r < 0)
2915 {
2916 errstr = US strerror(errno);
2917 close(s);
2918 goto defer;
2919 }
2920 close(s);
2921 if (r < len)
2922 {
2923 *log_msgptr =
2924 string_sprintf("\"udpsend\" truncated from %d to %d octets", len, r);
2925 return DEFER;
2926 }
2927
2928 HDEBUG(D_acl)
2929 debug_printf("udpsend %d bytes\n", r);
2930
2931 return OK;
2932
2933 defer:
2934 *log_msgptr = string_sprintf("\"udpsend\" failed: %s", errstr);
2935 return DEFER;
2936 }
2937
2938
2939
2940 /*************************************************
2941 * Handle conditions/modifiers on an ACL item *
2942 *************************************************/
2943
2944 /* Called from acl_check() below.
2945
2946 Arguments:
2947 verb ACL verb
2948 cb ACL condition block - if NULL, result is OK
2949 where where called from
2950 addr the address being checked for RCPT, or NULL
2951 level the nesting level
2952 epp pointer to pass back TRUE if "endpass" encountered
2953 (applies only to "accept" and "discard")
2954 user_msgptr user message pointer
2955 log_msgptr log message pointer
2956 basic_errno pointer to where to put verify error
2957
2958 Returns: OK - all conditions are met
2959 DISCARD - an "acl" condition returned DISCARD - only allowed
2960 for "accept" or "discard" verbs
2961 FAIL - at least one condition fails
2962 FAIL_DROP - an "acl" condition returned FAIL_DROP
2963 DEFER - can't tell at the moment (typically, lookup defer,
2964 but can be temporary callout problem)
2965 ERROR - ERROR from nested ACL or expansion failure or other
2966 error
2967 */
2968
2969 static int
2970 acl_check_condition(int verb, acl_condition_block *cb, int where,
2971 address_item *addr, int level, BOOL *epp, uschar **user_msgptr,
2972 uschar **log_msgptr, int *basic_errno)
2973 {
2974 uschar *user_message = NULL;
2975 uschar *log_message = NULL;
2976 uschar *debug_tag = NULL;
2977 uschar *debug_opts = NULL;
2978 uschar *p = NULL;
2979 int rc = OK;
2980 #ifdef WITH_CONTENT_SCAN
2981 int sep = '/';
2982 #endif
2983
2984 for (; cb != NULL; cb = cb->next)
2985 {
2986 uschar *arg;
2987 int control_type;
2988
2989 /* The message and log_message items set up messages to be used in
2990 case of rejection. They are expanded later. */
2991
2992 if (cb->type == ACLC_MESSAGE)
2993 {
2994 user_message = cb->arg;
2995 continue;
2996 }
2997
2998 if (cb->type == ACLC_LOG_MESSAGE)
2999 {
3000 log_message = cb->arg;
3001 continue;
3002 }
3003
3004 /* The endpass "condition" just sets a flag to show it occurred. This is
3005 checked at compile time to be on an "accept" or "discard" item. */
3006
3007 if (cb->type == ACLC_ENDPASS)
3008 {
3009 *epp = TRUE;
3010 continue;
3011 }
3012
3013 /* For other conditions and modifiers, the argument is expanded now for some
3014 of them, but not for all, because expansion happens down in some lower level
3015 checking functions in some cases. */
3016
3017 if (cond_expand_at_top[cb->type])
3018 {
3019 arg = expand_string(cb->arg);
3020 if (arg == NULL)
3021 {
3022 if (expand_string_forcedfail) continue;
3023 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s",
3024 cb->arg, expand_string_message);
3025 return search_find_defer? DEFER : ERROR;
3026 }
3027 }
3028 else arg = cb->arg;
3029
3030 /* Show condition, and expanded condition if it's different */
3031
3032 HDEBUG(D_acl)
3033 {
3034 int lhswidth = 0;
3035 debug_printf("check %s%s %n",
3036 (!cond_modifiers[cb->type] && cb->u.negated)? "!":"",
3037 conditions[cb->type], &lhswidth);
3038
3039 if (cb->type == ACLC_SET)
3040 {
3041 debug_printf("acl_%s ", cb->u.varname);
3042 lhswidth += 5 + Ustrlen(cb->u.varname);
3043 }
3044
3045 debug_printf("= %s\n", cb->arg);
3046
3047 if (arg != cb->arg)
3048 debug_printf("%.*s= %s\n", lhswidth,
3049 US" ", CS arg);
3050 }
3051
3052 /* Check that this condition makes sense at this time */
3053
3054 if ((cond_forbids[cb->type] & (1 << where)) != 0)
3055 {
3056 *log_msgptr = string_sprintf("cannot %s %s condition in %s ACL",
3057 cond_modifiers[cb->type]? "use" : "test",
3058 conditions[cb->type], acl_wherenames[where]);
3059 return ERROR;
3060 }
3061
3062 /* Run the appropriate test for each condition, or take the appropriate
3063 action for the remaining modifiers. */
3064
3065 switch(cb->type)
3066 {
3067 case ACLC_ADD_HEADER:
3068 setup_header(arg);
3069 break;
3070
3071 /* A nested ACL that returns "discard" makes sense only for an "accept" or
3072 "discard" verb. */
3073
3074 case ACLC_ACL:
3075 rc = acl_check_wargs(where, addr, arg, level+1, user_msgptr, log_msgptr);
3076 if (rc == DISCARD && verb != ACL_ACCEPT && verb != ACL_DISCARD)
3077 {
3078 *log_msgptr = string_sprintf("nested ACL returned \"discard\" for "
3079 "\"%s\" command (only allowed with \"accept\" or \"discard\")",
3080 verbs[verb]);
3081 return ERROR;
3082 }
3083 break;
3084
3085 case ACLC_AUTHENTICATED:
3086 rc = (sender_host_authenticated == NULL)? FAIL :
3087 match_isinlist(sender_host_authenticated, &arg, 0, NULL, NULL, MCL_STRING,
3088 TRUE, NULL);
3089 break;
3090
3091 #ifdef EXPERIMENTAL_BRIGHTMAIL
3092 case ACLC_BMI_OPTIN:
3093 {
3094 int old_pool = store_pool;
3095 store_pool = POOL_PERM;
3096 bmi_current_optin = string_copy(arg);
3097 store_pool = old_pool;
3098 }
3099 break;
3100 #endif
3101
3102 case ACLC_CONDITION:
3103 /* The true/false parsing here should be kept in sync with that used in
3104 expand.c when dealing with ECOND_BOOL so that we don't have too many
3105 different definitions of what can be a boolean. */
3106 if (*arg == '-'
3107 ? Ustrspn(arg+1, "0123456789") == Ustrlen(arg+1) /* Negative number */
3108 : Ustrspn(arg, "0123456789") == Ustrlen(arg)) /* Digits, or empty */
3109 rc = (Uatoi(arg) == 0)? FAIL : OK;
3110 else
3111 rc = (strcmpic(arg, US"no") == 0 ||
3112 strcmpic(arg, US"false") == 0)? FAIL :
3113 (strcmpic(arg, US"yes") == 0 ||
3114 strcmpic(arg, US"true") == 0)? OK : DEFER;
3115 if (rc == DEFER)
3116 *log_msgptr = string_sprintf("invalid \"condition\" value \"%s\"", arg);
3117 break;
3118
3119 case ACLC_CONTINUE: /* Always succeeds */
3120 break;
3121
3122 case ACLC_CONTROL:
3123 control_type = decode_control(arg, &p, where, log_msgptr);
3124
3125 /* Check if this control makes sense at this time */
3126
3127 if ((control_forbids[control_type] & (1 << where)) != 0)
3128 {
3129 *log_msgptr = string_sprintf("cannot use \"control=%s\" in %s ACL",
3130 controls[control_type], acl_wherenames[where]);
3131 return ERROR;
3132 }
3133
3134 switch(control_type)
3135 {
3136 case CONTROL_AUTH_UNADVERTISED:
3137 allow_auth_unadvertised = TRUE;
3138 break;
3139
3140 #ifdef EXPERIMENTAL_BRIGHTMAIL
3141 case CONTROL_BMI_RUN:
3142 bmi_run = 1;
3143 break;
3144 #endif
3145
3146 #ifndef DISABLE_DKIM
3147 case CONTROL_DKIM_VERIFY:
3148 dkim_disable_verify = TRUE;
3149 #ifdef EXPERIMENTAL_DMARC
3150 /* Since DKIM was blocked, skip DMARC too */
3151 dmarc_disable_verify = TRUE;
3152 dmarc_enable_forensic = FALSE;
3153 #endif
3154 break;
3155 #endif
3156
3157 #ifdef EXPERIMENTAL_DMARC
3158 case CONTROL_DMARC_VERIFY:
3159 dmarc_disable_verify = TRUE;
3160 break;
3161
3162 case CONTROL_DMARC_FORENSIC:
3163 dmarc_enable_forensic = TRUE;
3164 break;
3165 #endif
3166
3167 case CONTROL_DSCP:
3168 if (*p == '/')
3169 {
3170 int fd, af, level, optname, value;
3171 /* If we are acting on stdin, the setsockopt may fail if stdin is not
3172 a socket; we can accept that, we'll just debug-log failures anyway. */
3173 fd = fileno(smtp_in);
3174 af = ip_get_address_family(fd);
3175 if (af < 0)
3176 {
3177 HDEBUG(D_acl)
3178 debug_printf("smtp input is probably not a socket [%s], not setting DSCP\n",
3179 strerror(errno));
3180 break;
3181 }
3182 if (dscp_lookup(p+1, af, &level, &optname, &value))
3183 {
3184 if (setsockopt(fd, level, optname, &value, sizeof(value)) < 0)
3185 {
3186 HDEBUG(D_acl) debug_printf("failed to set input DSCP[%s]: %s\n",
3187 p+1, strerror(errno));
3188 }
3189 else
3190 {
3191 HDEBUG(D_acl) debug_printf("set input DSCP to \"%s\"\n", p+1);
3192 }
3193 }
3194 else
3195 {
3196 *log_msgptr = string_sprintf("unrecognised DSCP value in \"control=%s\"", arg);
3197 return ERROR;
3198 }
3199 }
3200 else
3201 {
3202 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3203 return ERROR;
3204 }
3205 break;
3206
3207 case CONTROL_ERROR:
3208 return ERROR;
3209
3210 case CONTROL_CASEFUL_LOCAL_PART:
3211 deliver_localpart = addr->cc_local_part;
3212 break;
3213
3214 case CONTROL_CASELOWER_LOCAL_PART:
3215 deliver_localpart = addr->lc_local_part;
3216 break;
3217
3218 case CONTROL_ENFORCE_SYNC:
3219 smtp_enforce_sync = TRUE;
3220 break;
3221
3222 case CONTROL_NO_ENFORCE_SYNC:
3223 smtp_enforce_sync = FALSE;
3224 break;
3225
3226 #ifdef WITH_CONTENT_SCAN
3227 case CONTROL_NO_MBOX_UNSPOOL:
3228 no_mbox_unspool = TRUE;
3229 break;
3230 #endif
3231
3232 case CONTROL_NO_MULTILINE:
3233 no_multiline_responses = TRUE;
3234 break;
3235
3236 case CONTROL_NO_PIPELINING:
3237 pipelining_enable = FALSE;
3238 break;
3239
3240 case CONTROL_NO_DELAY_FLUSH:
3241 disable_delay_flush = TRUE;
3242 break;
3243
3244 case CONTROL_NO_CALLOUT_FLUSH:
3245 disable_callout_flush = TRUE;
3246 break;
3247
3248 case CONTROL_FAKEDEFER:
3249 case CONTROL_FAKEREJECT:
3250 fake_response = (control_type == CONTROL_FAKEDEFER) ? DEFER : FAIL;
3251 if (*p == '/')
3252 {
3253 uschar *pp = p + 1;
3254 while (*pp != 0) pp++;
3255 fake_response_text = expand_string(string_copyn(p+1, pp-p-1));
3256 p = pp;
3257 }
3258 else
3259 {
3260 /* Explicitly reset to default string */
3261 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).";
3262 }
3263 break;
3264
3265 case CONTROL_FREEZE:
3266 deliver_freeze = TRUE;
3267 deliver_frozen_at = time(NULL);
3268 freeze_tell = freeze_tell_config; /* Reset to configured value */
3269 if (Ustrncmp(p, "/no_tell", 8) == 0)
3270 {
3271 p += 8;
3272 freeze_tell = NULL;
3273 }
3274 if (*p != 0)
3275 {
3276 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3277 return ERROR;
3278 }
3279 break;
3280
3281 case CONTROL_QUEUE_ONLY:
3282 queue_only_policy = TRUE;
3283 break;
3284
3285 case CONTROL_SUBMISSION:
3286 originator_name = US"";
3287 submission_mode = TRUE;
3288 while (*p == '/')
3289 {
3290 if (Ustrncmp(p, "/sender_retain", 14) == 0)
3291 {
3292 p += 14;
3293 active_local_sender_retain = TRUE;
3294 active_local_from_check = FALSE;
3295 }
3296 else if (Ustrncmp(p, "/domain=", 8) == 0)
3297 {
3298 uschar *pp = p + 8;
3299 while (*pp != 0 && *pp != '/') pp++;
3300 submission_domain = string_copyn(p+8, pp-p-8);
3301 p = pp;
3302 }
3303 /* The name= option must be last, because it swallows the rest of
3304 the string. */
3305 else if (Ustrncmp(p, "/name=", 6) == 0)
3306 {
3307 uschar *pp = p + 6;
3308 while (*pp != 0) pp++;
3309 submission_name = string_copy(parse_fix_phrase(p+6, pp-p-6,
3310 big_buffer, big_buffer_size));
3311 p = pp;
3312 }
3313 else break;
3314 }
3315 if (*p != 0)
3316 {
3317 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3318 return ERROR;
3319 }
3320 break;
3321
3322 case CONTROL_DEBUG:
3323 while (*p == '/')
3324 {
3325 if (Ustrncmp(p, "/tag=", 5) == 0)
3326 {
3327 uschar *pp = p + 5;
3328 while (*pp != '\0' && *pp != '/') pp++;
3329 debug_tag = string_copyn(p+5, pp-p-5);
3330 p = pp;
3331 }
3332 else if (Ustrncmp(p, "/opts=", 6) == 0)
3333 {
3334 uschar *pp = p + 6;
3335 while (*pp != '\0' && *pp != '/') pp++;
3336 debug_opts = string_copyn(p+6, pp-p-6);
3337 p = pp;
3338 }
3339 }
3340 debug_logging_activate(debug_tag, debug_opts);
3341 break;
3342
3343 case CONTROL_SUPPRESS_LOCAL_FIXUPS:
3344 suppress_local_fixups = TRUE;
3345 break;
3346
3347 case CONTROL_CUTTHROUGH_DELIVERY:
3348 if (deliver_freeze)
3349 {
3350 *log_msgptr = string_sprintf("\"control=%s\" on frozen item", arg);
3351 return ERROR;
3352 }
3353 if (queue_only_policy)
3354 {
3355 *log_msgptr = string_sprintf("\"control=%s\" on queue-only item", arg);
3356 return ERROR;
3357 }
3358 cutthrough_delivery = TRUE;
3359 break;
3360 }
3361 break;
3362
3363 #ifdef EXPERIMENTAL_DCC
3364 case ACLC_DCC:
3365 {
3366 /* Seperate the regular expression and any optional parameters. */
3367 uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size);
3368 /* Run the dcc backend. */
3369 rc = dcc_process(&ss);
3370 /* Modify return code based upon the existance of options. */
3371 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
3372 != NULL) {
3373 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
3374 {
3375 /* FAIL so that the message is passed to the next ACL */
3376 rc = FAIL;
3377 }
3378 }
3379 }
3380 break;
3381 #endif
3382
3383 #ifdef WITH_CONTENT_SCAN
3384 case ACLC_DECODE:
3385 rc = mime_decode(&arg);
3386 break;
3387 #endif
3388
3389 case ACLC_DELAY:
3390 {
3391 int delay = readconf_readtime(arg, 0, FALSE);
3392 if (delay < 0)
3393 {
3394 *log_msgptr = string_sprintf("syntax error in argument for \"delay\" "
3395 "modifier: \"%s\" is not a time value", arg);
3396 return ERROR;
3397 }
3398 else
3399 {
3400 HDEBUG(D_acl) debug_printf("delay modifier requests %d-second delay\n",
3401 delay);
3402 if (host_checking)
3403 {
3404 HDEBUG(D_acl)
3405 debug_printf("delay skipped in -bh checking mode\n");
3406 }
3407
3408 /* It appears to be impossible to detect that a TCP/IP connection has
3409 gone away without reading from it. This means that we cannot shorten
3410 the delay below if the client goes away, because we cannot discover
3411 that the client has closed its end of the connection. (The connection
3412 is actually in a half-closed state, waiting for the server to close its
3413 end.) It would be nice to be able to detect this state, so that the
3414 Exim process is not held up unnecessarily. However, it seems that we
3415 can't. The poll() function does not do the right thing, and in any case
3416 it is not always available.
3417
3418 NOTE 1: If ever this state of affairs changes, remember that we may be
3419 dealing with stdin/stdout here, in addition to TCP/IP connections.
3420 Also, delays may be specified for non-SMTP input, where smtp_out and
3421 smtp_in will be NULL. Whatever is done must work in all cases.
3422
3423 NOTE 2: The added feature of flushing the output before a delay must
3424 apply only to SMTP input. Hence the test for smtp_out being non-NULL.
3425 */
3426
3427 else
3428 {
3429 if (smtp_out != NULL && !disable_delay_flush) mac_smtp_fflush();
3430 while (delay > 0) delay = sleep(delay);
3431 }
3432 }
3433 }
3434 break;
3435
3436 #ifdef WITH_OLD_DEMIME
3437 case ACLC_DEMIME:
3438 rc = demime(&arg);
3439 break;
3440 #endif
3441
3442 #ifndef DISABLE_DKIM
3443 case ACLC_DKIM_SIGNER:
3444 if (dkim_cur_signer != NULL)
3445 rc = match_isinlist(dkim_cur_signer,
3446 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
3447 else
3448 rc = FAIL;
3449 break;
3450
3451 case ACLC_DKIM_STATUS:
3452 rc = match_isinlist(dkim_exim_expand_query(DKIM_VERIFY_STATUS),
3453 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
3454 break;
3455 #endif
3456
3457 #ifdef EXPERIMENTAL_DMARC
3458 case ACLC_DMARC_STATUS:
3459 if (!dmarc_has_been_checked)
3460 dmarc_process();
3461 dmarc_has_been_checked = TRUE;
3462 /* used long way of dmarc_exim_expand_query() in case we need more
3463 * view into the process in the future. */
3464 rc = match_isinlist(dmarc_exim_expand_query(DMARC_VERIFY_STATUS),
3465 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
3466 break;
3467 #endif
3468
3469 case ACLC_DNSLISTS:
3470 rc = verify_check_dnsbl(&arg);
3471 break;
3472
3473 case ACLC_DOMAINS:
3474 rc = match_isinlist(addr->domain, &arg, 0, &domainlist_anchor,
3475 addr->domain_cache, MCL_DOMAIN, TRUE, &deliver_domain_data);
3476 break;
3477
3478 /* The value in tls_cipher is the full cipher name, for example,
3479 TLSv1:DES-CBC3-SHA:168, whereas the values to test for are just the
3480 cipher names such as DES-CBC3-SHA. But program defensively. We don't know
3481 what may in practice come out of the SSL library - which at the time of
3482 writing is poorly documented. */
3483
3484 case ACLC_ENCRYPTED:
3485 if (tls_in.cipher == NULL) rc = FAIL; else
3486 {
3487 uschar *endcipher = NULL;
3488 uschar *cipher = Ustrchr(tls_in.cipher, ':');
3489 if (cipher == NULL) cipher = tls_in.cipher; else
3490 {
3491 endcipher = Ustrchr(++cipher, ':');
3492 if (endcipher != NULL) *endcipher = 0;
3493 }
3494 rc = match_isinlist(cipher, &arg, 0, NULL, NULL, MCL_STRING, TRUE, NULL);
3495 if (endcipher != NULL) *endcipher = ':';
3496 }
3497 break;
3498
3499 /* Use verify_check_this_host() instead of verify_check_host() so that
3500 we can pass over &host_data to catch any looked up data. Once it has been
3501 set, it retains its value so that it's still there if another ACL verb
3502 comes through here and uses the cache. However, we must put it into
3503 permanent store in case it is also expected to be used in a subsequent
3504 message in the same SMTP connection. */
3505
3506 case ACLC_HOSTS:
3507 rc = verify_check_this_host(&arg, sender_host_cache, NULL,
3508 (sender_host_address == NULL)? US"" : sender_host_address, &host_data);
3509 if (host_data != NULL) host_data = string_copy_malloc(host_data);
3510 break;
3511
3512 case ACLC_LOCAL_PARTS:
3513 rc = match_isinlist(addr->cc_local_part, &arg, 0,
3514 &localpartlist_anchor, addr->localpart_cache, MCL_LOCALPART, TRUE,
3515 &deliver_localpart_data);
3516 break;
3517
3518 case ACLC_LOG_REJECT_TARGET:
3519 {
3520 int logbits = 0;
3521 int sep = 0;
3522 uschar *s = arg;
3523 uschar *ss;
3524 while ((ss = string_nextinlist(&s, &sep, big_buffer, big_buffer_size))
3525 != NULL)
3526 {
3527 if (Ustrcmp(ss, "main") == 0) logbits |= LOG_MAIN;
3528 else if (Ustrcmp(ss, "panic") == 0) logbits |= LOG_PANIC;
3529 else if (Ustrcmp(ss, "reject") == 0) logbits |= LOG_REJECT;
3530 else
3531 {
3532 logbits |= LOG_MAIN|LOG_REJECT;
3533 log_write(0, LOG_MAIN|LOG_PANIC, "unknown log name \"%s\" in "
3534 "\"log_reject_target\" in %s ACL", ss, acl_wherenames[where]);
3535 }
3536 }
3537 log_reject_target = logbits;
3538 }
3539 break;
3540
3541 case ACLC_LOGWRITE:
3542 {
3543 int logbits = 0;
3544 uschar *s = arg;
3545 if (*s == ':')
3546 {
3547 s++;
3548 while (*s != ':')
3549 {
3550 if (Ustrncmp(s, "main", 4) == 0)
3551 { logbits |= LOG_MAIN; s += 4; }
3552 else if (Ustrncmp(s, "panic", 5) == 0)
3553 { logbits |= LOG_PANIC; s += 5; }
3554 else if (Ustrncmp(s, "reject", 6) == 0)
3555 { logbits |= LOG_REJECT; s += 6; }
3556 else
3557 {
3558 logbits = LOG_MAIN|LOG_PANIC;
3559 s = string_sprintf(":unknown log name in \"%s\" in "
3560 "\"logwrite\" in %s ACL", arg, acl_wherenames[where]);
3561 }
3562 if (*s == ',') s++;
3563 }
3564 s++;
3565 }
3566 while (isspace(*s)) s++;
3567
3568
3569 if (logbits == 0) logbits = LOG_MAIN;
3570 log_write(0, logbits, "%s", string_printing(s));
3571 }
3572 break;
3573
3574 #ifdef WITH_CONTENT_SCAN
3575 case ACLC_MALWARE:
3576 {
3577 /* Separate the regular expression and any optional parameters. */
3578 uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size);
3579 /* Run the malware backend. */
3580 rc = malware(&ss);
3581 /* Modify return code based upon the existance of options. */
3582 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
3583 != NULL) {
3584 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
3585 {
3586 /* FAIL so that the message is passed to the next ACL */
3587 rc = FAIL;
3588 }
3589 }
3590 }
3591 break;
3592
3593 case ACLC_MIME_REGEX:
3594 rc = mime_regex(&arg);
3595 break;
3596 #endif
3597
3598 case ACLC_RATELIMIT:
3599 rc = acl_ratelimit(arg, where, log_msgptr);
3600 break;
3601
3602 case ACLC_RECIPIENTS:
3603 rc = match_address_list(addr->address, TRUE, TRUE, &arg, NULL, -1, 0,
3604 &recipient_data);
3605 break;
3606
3607 #ifdef WITH_CONTENT_SCAN
3608 case ACLC_REGEX:
3609 rc = regex(&arg);
3610 break;
3611 #endif
3612
3613 case ACLC_REMOVE_HEADER:
3614 setup_remove_header(arg);
3615 break;
3616
3617 case ACLC_SENDER_DOMAINS:
3618 {
3619 uschar *sdomain;
3620 sdomain = Ustrrchr(sender_address, '@');
3621 sdomain = (sdomain == NULL)? US"" : sdomain + 1;
3622 rc = match_isinlist(sdomain, &arg, 0, &domainlist_anchor,
3623 sender_domain_cache, MCL_DOMAIN, TRUE, NULL);
3624 }
3625 break;
3626
3627 case ACLC_SENDERS:
3628 rc = match_address_list(sender_address, TRUE, TRUE, &arg,
3629 sender_address_cache, -1, 0, &sender_data);
3630 break;
3631
3632 /* Connection variables must persist forever */
3633
3634 case ACLC_SET:
3635 {
3636 int old_pool = store_pool;
3637 if (cb->u.varname[0] == 'c') store_pool = POOL_PERM;
3638 acl_var_create(cb->u.varname)->data.ptr = string_copy(arg);
3639 store_pool = old_pool;
3640 }
3641 break;
3642
3643 #ifdef WITH_CONTENT_SCAN
3644 case ACLC_SPAM:
3645 {
3646 /* Seperate the regular expression and any optional parameters. */
3647 uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size);
3648 /* Run the spam backend. */
3649 rc = spam(&ss);
3650 /* Modify return code based upon the existance of options. */
3651 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
3652 != NULL) {
3653 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
3654 {
3655 /* FAIL so that the message is passed to the next ACL */
3656 rc = FAIL;
3657 }
3658 }
3659 }
3660 break;
3661 #endif
3662
3663 #ifdef EXPERIMENTAL_SPF
3664 case ACLC_SPF:
3665 rc = spf_process(&arg, sender_address, SPF_PROCESS_NORMAL);
3666 break;
3667 case ACLC_SPF_GUESS:
3668 rc = spf_process(&arg, sender_address, SPF_PROCESS_GUESS);
3669 break;
3670 #endif
3671
3672 case ACLC_UDPSEND:
3673 rc = acl_udpsend(arg, log_msgptr);
3674 break;
3675
3676 /* If the verb is WARN, discard any user message from verification, because
3677 such messages are SMTP responses, not header additions. The latter come
3678 only from explicit "message" modifiers. However, put the user message into
3679 $acl_verify_message so it can be used in subsequent conditions or modifiers
3680 (until something changes it). */
3681
3682 case ACLC_VERIFY:
3683 rc = acl_verify(where, addr, arg, user_msgptr, log_msgptr, basic_errno);
3684 acl_verify_message = *user_msgptr;
3685 if (verb == ACL_WARN) *user_msgptr = NULL;
3686 break;
3687
3688 default:
3689 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown "
3690 "condition %d", cb->type);
3691 break;
3692 }
3693
3694 /* If a condition was negated, invert OK/FAIL. */
3695
3696 if (!cond_modifiers[cb->type] && cb->u.negated)
3697 {
3698 if (rc == OK) rc = FAIL;
3699 else if (rc == FAIL || rc == FAIL_DROP) rc = OK;
3700 }
3701
3702 if (rc != OK) break; /* Conditions loop */
3703 }
3704
3705
3706 /* If the result is the one for which "message" and/or "log_message" are used,
3707 handle the values of these modifiers. If there isn't a log message set, we make
3708 it the same as the user message.
3709
3710 "message" is a user message that will be included in an SMTP response. Unless
3711 it is empty, it overrides any previously set user message.
3712
3713 "log_message" is a non-user message, and it adds to any existing non-user
3714 message that is already set.
3715
3716 Most verbs have but a single return for which the messages are relevant, but
3717 for "discard", it's useful to have the log message both when it succeeds and
3718 when it fails. For "accept", the message is used in the OK case if there is no
3719 "endpass", but (for backwards compatibility) in the FAIL case if "endpass" is
3720 present. */
3721
3722 if (*epp && rc == OK) user_message = NULL;
3723
3724 if (((1<<rc) & msgcond[verb]) != 0)
3725 {
3726 uschar *expmessage;
3727 uschar *old_user_msgptr = *user_msgptr;
3728 uschar *old_log_msgptr = (*log_msgptr != NULL)? *log_msgptr : old_user_msgptr;
3729
3730 /* If the verb is "warn", messages generated by conditions (verification or
3731 nested ACLs) are always discarded. This also happens for acceptance verbs
3732 when they actually do accept. Only messages specified at this level are used.
3733 However, the value of an existing message is available in $acl_verify_message
3734 during expansions. */
3735
3736 if (verb == ACL_WARN ||
3737 (rc == OK && (verb == ACL_ACCEPT || verb == ACL_DISCARD)))
3738 *log_msgptr = *user_msgptr = NULL;
3739
3740 if (user_message != NULL)
3741 {
3742 acl_verify_message = old_user_msgptr;
3743 expmessage = expand_string(user_message);
3744 if (expmessage == NULL)
3745 {
3746 if (!expand_string_forcedfail)
3747 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
3748 user_message, expand_string_message);
3749 }
3750 else if (expmessage[0] != 0) *user_msgptr = expmessage;
3751 }
3752
3753 if (log_message != NULL)
3754 {
3755 acl_verify_message = old_log_msgptr;
3756 expmessage = expand_string(log_message);
3757 if (expmessage == NULL)
3758 {
3759 if (!expand_string_forcedfail)
3760 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
3761 log_message, expand_string_message);
3762 }
3763 else if (expmessage[0] != 0)
3764 {
3765 *log_msgptr = (*log_msgptr == NULL)? expmessage :
3766 string_sprintf("%s: %s", expmessage, *log_msgptr);
3767 }
3768 }
3769
3770 /* If no log message, default it to the user message */
3771
3772 if (*log_msgptr == NULL) *log_msgptr = *user_msgptr;
3773 }
3774
3775 acl_verify_message = NULL;
3776 return rc;
3777 }
3778
3779
3780
3781
3782
3783 /*************************************************
3784 * Get line from a literal ACL *
3785 *************************************************/
3786
3787 /* This function is passed to acl_read() in order to extract individual lines
3788 of a literal ACL, which we access via static pointers. We can destroy the
3789 contents because this is called only once (the compiled ACL is remembered).
3790
3791 This code is intended to treat the data in the same way as lines in the main
3792 Exim configuration file. That is:
3793
3794 . Leading spaces are ignored.
3795
3796 . A \ at the end of a line is a continuation - trailing spaces after the \
3797 are permitted (this is because I don't believe in making invisible things
3798 significant). Leading spaces on the continued part of a line are ignored.
3799
3800 . Physical lines starting (significantly) with # are totally ignored, and
3801 may appear within a sequence of backslash-continued lines.
3802
3803 . Blank lines are ignored, but will end a sequence of continuations.
3804
3805 Arguments: none
3806 Returns: a pointer to the next line
3807 */
3808
3809
3810 static uschar *acl_text; /* Current pointer in the text */
3811 static uschar *acl_text_end; /* Points one past the terminating '0' */
3812
3813
3814 static uschar *
3815 acl_getline(void)
3816 {
3817 uschar *yield;
3818
3819 /* This loop handles leading blank lines and comments. */
3820
3821 for(;;)
3822 {
3823 while (isspace(*acl_text)) acl_text++; /* Leading spaces/empty lines */
3824 if (*acl_text == 0) return NULL; /* No more data */
3825 yield = acl_text; /* Potential data line */
3826
3827 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3828
3829 /* If we hit the end before a newline, we have the whole logical line. If
3830 it's a comment, there's no more data to be given. Otherwise, yield it. */
3831
3832 if (*acl_text == 0) return (*yield == '#')? NULL : yield;
3833
3834 /* After reaching a newline, end this loop if the physical line does not
3835 start with '#'. If it does, it's a comment, and the loop continues. */
3836
3837 if (*yield != '#') break;
3838 }
3839
3840 /* This loop handles continuations. We know we have some real data, ending in
3841 newline. See if there is a continuation marker at the end (ignoring trailing
3842 white space). We know that *yield is not white space, so no need to test for
3843 cont > yield in the backwards scanning loop. */
3844
3845 for(;;)
3846 {
3847 uschar *cont;
3848 for (cont = acl_text - 1; isspace(*cont); cont--);
3849
3850 /* If no continuation follows, we are done. Mark the end of the line and
3851 return it. */
3852
3853 if (*cont != '\\')
3854 {
3855 *acl_text++ = 0;
3856 return yield;
3857 }
3858
3859 /* We have encountered a continuation. Skip over whitespace at the start of
3860 the next line, and indeed the whole of the next line or lines if they are
3861 comment lines. */
3862
3863 for (;;)
3864 {
3865 while (*(++acl_text) == ' ' || *acl_text == '\t');
3866 if (*acl_text != '#') break;
3867 while (*(++acl_text) != 0 && *acl_text != '\n');
3868 }
3869
3870 /* We have the start of a continuation line. Move all the rest of the data
3871 to join onto the previous line, and then find its end. If the end is not a
3872 newline, we are done. Otherwise loop to look for another continuation. */
3873
3874 memmove(cont, acl_text, acl_text_end - acl_text);
3875 acl_text_end -= acl_text - cont;
3876 acl_text = cont;
3877 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3878 if (*acl_text == 0) return yield;
3879 }
3880
3881 /* Control does not reach here */
3882 }
3883
3884
3885
3886
3887
3888 /*************************************************
3889 * Check access using an ACL *
3890 *************************************************/
3891
3892 /* This function is called from address_check. It may recurse via
3893 acl_check_condition() - hence the use of a level to stop looping. The ACL is
3894 passed as a string which is expanded. A forced failure implies no access check
3895 is required. If the result is a single word, it is taken as the name of an ACL
3896 which is sought in the global ACL tree. Otherwise, it is taken as literal ACL
3897 text, complete with newlines, and parsed as such. In both cases, the ACL check
3898 is then run. This function uses an auxiliary function for acl_read() to call
3899 for reading individual lines of a literal ACL. This is acl_getline(), which
3900 appears immediately above.
3901
3902 Arguments:
3903 where where called from
3904 addr address item when called from RCPT; otherwise NULL
3905 s the input string; NULL is the same as an empty ACL => DENY
3906 level the nesting level
3907 user_msgptr where to put a user error (for SMTP response)
3908 log_msgptr where to put a logging message (not for SMTP response)
3909
3910 Returns: OK access is granted
3911 DISCARD access is apparently granted...
3912 FAIL access is denied
3913 FAIL_DROP access is denied; drop the connection
3914 DEFER can't tell at the moment
3915 ERROR disaster
3916 */
3917
3918 static int
3919 acl_check_internal(int where, address_item *addr, uschar *s, int level,
3920 uschar **user_msgptr, uschar **log_msgptr)
3921 {
3922 int fd = -1;
3923 acl_block *acl = NULL;
3924 uschar *acl_name = US"inline ACL";
3925 uschar *ss;
3926
3927 /* Catch configuration loops */
3928
3929 if (level > 20)
3930 {
3931 *log_msgptr = US"ACL nested too deep: possible loop";
3932 return ERROR;
3933 }
3934
3935 if (s == NULL)
3936 {
3937 HDEBUG(D_acl) debug_printf("ACL is NULL: implicit DENY\n");
3938 return FAIL;
3939 }
3940
3941 /* At top level, we expand the incoming string. At lower levels, it has already
3942 been expanded as part of condition processing. */
3943
3944 if (level == 0)
3945 {
3946 ss = expand_string(s);
3947 if (ss == NULL)
3948 {
3949 if (expand_string_forcedfail) return OK;
3950 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s", s,
3951 expand_string_message);
3952 return ERROR;
3953 }
3954 }
3955 else ss = s;
3956
3957 while (isspace(*ss))ss++;
3958
3959 /* If we can't find a named ACL, the default is to parse it as an inline one.
3960 (Unless it begins with a slash; non-existent files give rise to an error.) */
3961
3962 acl_text = ss;
3963
3964 /* Handle the case of a string that does not contain any spaces. Look for a
3965 named ACL among those read from the configuration, or a previously read file.
3966 It is possible that the pointer to the ACL is NULL if the configuration
3967 contains a name with no data. If not found, and the text begins with '/',
3968 read an ACL from a file, and save it so it can be re-used. */
3969
3970 if (Ustrchr(ss, ' ') == NULL)
3971 {
3972 tree_node *t = tree_search(acl_anchor, ss);
3973 if (t != NULL)
3974 {
3975 acl = (acl_block *)(t->data.ptr);
3976 if (acl == NULL)
3977 {
3978 HDEBUG(D_acl) debug_printf("ACL \"%s\" is empty: implicit DENY\n", ss);
3979 return FAIL;
3980 }
3981 acl_name = string_sprintf("ACL \"%s\"", ss);
3982 HDEBUG(D_acl) debug_printf("using ACL \"%s\"\n", ss);
3983 }
3984
3985 else if (*ss == '/')
3986 {
3987 struct stat statbuf;
3988 fd = Uopen(ss, O_RDONLY, 0);
3989 if (fd < 0)
3990 {
3991 *log_msgptr = string_sprintf("failed to open ACL file \"%s\": %s", ss,
3992 strerror(errno));
3993 return ERROR;
3994 }
3995
3996 if (fstat(fd, &statbuf) != 0)
3997 {
3998 *log_msgptr = string_sprintf("failed to fstat ACL file \"%s\": %s", ss,
3999 strerror(errno));
4000 return ERROR;
4001 }
4002
4003 acl_text = store_get(statbuf.st_size + 1);
4004 acl_text_end = acl_text + statbuf.st_size + 1;
4005
4006 if (read(fd, acl_text, statbuf.st_size) != statbuf.st_size)
4007 {
4008 *log_msgptr = string_sprintf("failed to read ACL file \"%s\": %s",
4009 ss, strerror(errno));
4010 return ERROR;
4011 }
4012 acl_text[statbuf.st_size] = 0;
4013 (void)close(fd);
4014
4015 acl_name = string_sprintf("ACL \"%s\"", ss);
4016 HDEBUG(D_acl) debug_printf("read ACL from file %s\n", ss);
4017 }
4018 }
4019
4020 /* Parse an ACL that is still in text form. If it came from a file, remember it
4021 in the ACL tree, having read it into the POOL_PERM store pool so that it
4022 persists between multiple messages. */
4023
4024 if (acl == NULL)
4025 {
4026 int old_pool = store_pool;
4027 if (fd >= 0) store_pool = POOL_PERM;
4028 acl = acl_read(acl_getline, log_msgptr);
4029 store_pool = old_pool;
4030 if (acl == NULL && *log_msgptr != NULL) return ERROR;
4031 if (fd >= 0)
4032 {
4033 tree_node *t = store_get_perm(sizeof(tree_node) + Ustrlen(ss));
4034 Ustrcpy(t->name, ss);
4035 t->data.ptr = acl;
4036 (void)tree_insertnode(&acl_anchor, t);
4037 }
4038 }
4039
4040 /* Now we have an ACL to use. It's possible it may be NULL. */
4041
4042 while (acl != NULL)
4043 {
4044 int cond;
4045 int basic_errno = 0;
4046 BOOL endpass_seen = FALSE;
4047
4048 *log_msgptr = *user_msgptr = NULL;
4049 acl_temp_details = FALSE;
4050
4051 if ((where == ACL_WHERE_QUIT || where == ACL_WHERE_NOTQUIT) &&
4052 acl->verb != ACL_ACCEPT &&
4053 acl->verb != ACL_WARN)
4054 {
4055 *log_msgptr = string_sprintf("\"%s\" is not allowed in a QUIT or not-QUIT ACL",
4056 verbs[acl->verb]);
4057 return ERROR;
4058 }
4059
4060 HDEBUG(D_acl) debug_printf("processing \"%s\"\n", verbs[acl->verb]);
4061
4062 /* Clear out any search error message from a previous check before testing
4063 this condition. */
4064
4065 search_error_message = NULL;
4066 cond = acl_check_condition(acl->verb, acl->condition, where, addr, level,
4067 &endpass_seen, user_msgptr, log_msgptr, &basic_errno);
4068
4069 /* Handle special returns: DEFER causes a return except on a WARN verb;
4070 ERROR always causes a return. */
4071
4072 switch (cond)
4073 {
4074 case DEFER:
4075 HDEBUG(D_acl) debug_printf("%s: condition test deferred in %s\n", verbs[acl->verb], acl_name);
4076 if (basic_errno != ERRNO_CALLOUTDEFER)
4077 {
4078 if (search_error_message != NULL && *search_error_message != 0)
4079 *log_msgptr = search_error_message;
4080 if (smtp_return_error_details) acl_temp_details = TRUE;
4081 }
4082 else
4083 {
4084 acl_temp_details = TRUE;
4085 }
4086 if (acl->verb != ACL_WARN) return DEFER;
4087 break;
4088
4089 default: /* Paranoia */
4090 case ERROR:
4091 HDEBUG(D_acl) debug_printf("%s: condition test error in %s\n", verbs[acl->verb], acl_name);
4092 return ERROR;
4093
4094 case OK:
4095 HDEBUG(D_acl) debug_printf("%s: condition test succeeded in %s\n",
4096 verbs[acl->verb], acl_name);
4097 break;
4098
4099 case FAIL:
4100 HDEBUG(D_acl) debug_printf("%s: condition test failed in %s\n", verbs[acl->verb], acl_name);
4101 break;
4102
4103 /* DISCARD and DROP can happen only from a nested ACL condition, and
4104 DISCARD can happen only for an "accept" or "discard" verb. */
4105
4106 case DISCARD:
4107 HDEBUG(D_acl) debug_printf("%s: condition test yielded \"discard\" in %s\n",
4108 verbs[acl->verb], acl_name);
4109 break;
4110
4111 case FAIL_DROP:
4112 HDEBUG(D_acl) debug_printf("%s: condition test yielded \"drop\" in %s\n",
4113 verbs[acl->verb], acl_name);
4114 break;
4115 }
4116
4117 /* At this point, cond for most verbs is either OK or FAIL or (as a result of
4118 a nested ACL condition) FAIL_DROP. However, for WARN, cond may be DEFER, and
4119 for ACCEPT and DISCARD, it may be DISCARD after a nested ACL call. */
4120
4121 switch(acl->verb)
4122 {
4123 case ACL_ACCEPT:
4124 if (cond == OK || cond == DISCARD) return cond;
4125 if (endpass_seen)
4126 {
4127 HDEBUG(D_acl) debug_printf("accept: endpass encountered - denying access\n");
4128 return cond;
4129 }
4130 break;
4131
4132 case ACL_DEFER:
4133 if (cond == OK)
4134 {
4135 acl_temp_details = TRUE;
4136 return DEFER;
4137 }
4138 break;
4139
4140 case ACL_DENY:
4141 if (cond == OK) return FAIL;
4142 break;
4143
4144 case ACL_DISCARD:
4145 if (cond == OK || cond == DISCARD) return DISCARD;
4146 if (endpass_seen)
4147 {
4148 HDEBUG(D_acl) debug_printf("discard: endpass encountered - denying access\n");
4149 return cond;
4150 }
4151 break;
4152
4153 case ACL_DROP:
4154 if (cond == OK) return FAIL_DROP;
4155 break;
4156
4157 case ACL_REQUIRE:
4158 if (cond != OK) return cond;
4159 break;
4160
4161 case ACL_WARN:
4162 if (cond == OK)
4163 acl_warn(where, *user_msgptr, *log_msgptr);
4164 else if (cond == DEFER && (log_extra_selector & LX_acl_warn_skipped) != 0)
4165 log_write(0, LOG_MAIN, "%s Warning: ACL \"warn\" statement skipped: "
4166 "condition test deferred%s%s", host_and_ident(TRUE),
4167 (*log_msgptr == NULL)? US"" : US": ",
4168 (*log_msgptr == NULL)? US"" : *log_msgptr);
4169 *log_msgptr = *user_msgptr = NULL; /* In case implicit DENY follows */
4170 break;
4171
4172 default:
4173 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown verb %d",
4174 acl->verb);
4175 break;
4176 }
4177
4178 /* Pass to the next ACL item */
4179
4180 acl = acl->next;
4181 }
4182
4183 /* We have reached the end of the ACL. This is an implicit DENY. */
4184
4185 HDEBUG(D_acl) debug_printf("end of %s: implicit DENY\n", acl_name);
4186 return FAIL;
4187 }
4188
4189
4190
4191
4192 /* Same args as acl_check_internal() above, but the string s is
4193 the name of an ACL followed optionally by up to 9 space-separated arguments.
4194 The name and args are separately expanded. Args go into $acl_arg globals. */
4195 static int
4196 acl_check_wargs(int where, address_item *addr, uschar *s, int level,
4197 uschar **user_msgptr, uschar **log_msgptr)
4198 {
4199 uschar * tmp;
4200 uschar * tmp_arg[9]; /* must match acl_arg[] */
4201 uschar * sav_arg[9]; /* must match acl_arg[] */
4202 int sav_narg;
4203 uschar * name;
4204 int i;
4205 int ret;
4206
4207 if (!(tmp = string_dequote(&s)) || !(name = expand_string(tmp)))
4208 goto bad;
4209
4210 for (i = 0; i < 9; i++)
4211 {
4212 while (*s && isspace(*s)) s++;
4213 if (!*s) break;
4214 if (!(tmp = string_dequote(&s)) || !(tmp_arg[i] = expand_string(tmp)))
4215 {
4216 tmp = name;
4217 goto bad;
4218 }
4219 }
4220
4221 sav_narg = acl_narg;
4222 acl_narg = i;
4223 for (i = 0; i < acl_narg; i++)
4224 {
4225 sav_arg[i] = acl_arg[i];
4226 acl_arg[i] = tmp_arg[i];
4227 }
4228 while (i < 9)
4229 {
4230 sav_arg[i] = acl_arg[i];
4231 acl_arg[i++] = NULL;
4232 }
4233
4234 ret = acl_check_internal(where, addr, name, level, user_msgptr, log_msgptr);
4235
4236 acl_narg = sav_narg;
4237 for (i = 0; i < 9; i++) acl_arg[i] = sav_arg[i];
4238 return ret;
4239
4240 bad:
4241 if (expand_string_forcedfail) return ERROR;
4242 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s",
4243 tmp, expand_string_message);
4244 return search_find_defer?DEFER:ERROR;
4245 }
4246
4247
4248
4249 /*************************************************
4250 * Check access using an ACL *
4251 *************************************************/
4252
4253 /* Alternate interface for ACL, used by expansions */
4254 int
4255 acl_eval(int where, uschar *s, uschar **user_msgptr, uschar **log_msgptr)
4256 {
4257 address_item adb;
4258 address_item *addr = NULL;
4259
4260 *user_msgptr = *log_msgptr = NULL;
4261 sender_verified_failed = NULL;
4262 ratelimiters_cmd = NULL;
4263 log_reject_target = LOG_MAIN|LOG_REJECT;
4264
4265 if (where == ACL_WHERE_RCPT)
4266 {
4267 adb = address_defaults;
4268 addr = &adb;
4269 addr->address = expand_string(US"$local_part@$domain");
4270 addr->domain = deliver_domain;
4271 addr->local_part = deliver_localpart;
4272 addr->cc_local_part = deliver_localpart;
4273 addr->lc_local_part = deliver_localpart;
4274 }
4275
4276 return acl_check_internal(where, addr, s, 0, user_msgptr, log_msgptr);
4277 }
4278
4279
4280
4281 /* This is the external interface for ACL checks. It sets up an address and the
4282 expansions for $domain and $local_part when called after RCPT, then calls
4283 acl_check_internal() to do the actual work.
4284
4285 Arguments:
4286 where ACL_WHERE_xxxx indicating where called from
4287 recipient RCPT address for RCPT check, else NULL
4288 s the input string; NULL is the same as an empty ACL => DENY
4289 user_msgptr where to put a user error (for SMTP response)
4290 log_msgptr where to put a logging message (not for SMTP response)
4291
4292 Returns: OK access is granted by an ACCEPT verb
4293 DISCARD access is granted by a DISCARD verb
4294 FAIL access is denied
4295 FAIL_DROP access is denied; drop the connection
4296 DEFER can't tell at the moment
4297 ERROR disaster
4298 */
4299 int acl_where = ACL_WHERE_UNKNOWN;
4300
4301 int
4302 acl_check(int where, uschar *recipient, uschar *s, uschar **user_msgptr,
4303 uschar **log_msgptr)
4304 {
4305 int rc;
4306 address_item adb;
4307 address_item *addr = NULL;
4308
4309 *user_msgptr = *log_msgptr = NULL;
4310 sender_verified_failed = NULL;
4311 ratelimiters_cmd = NULL;
4312 log_reject_target = LOG_MAIN|LOG_REJECT;
4313
4314 #ifdef EXPERIMENTAL_PRDR
4315 if (where == ACL_WHERE_RCPT || where == ACL_WHERE_PRDR )
4316 #else
4317 if (where == ACL_WHERE_RCPT )
4318 #endif
4319 {
4320 adb = address_defaults;
4321 addr = &adb;
4322 addr->address = recipient;
4323 if (deliver_split_address(addr) == DEFER)
4324 {
4325 *log_msgptr = US"defer in percent_hack_domains check";
4326 return DEFER;
4327 }
4328 deliver_domain = addr->domain;
4329 deliver_localpart = addr->local_part;
4330 }
4331
4332 acl_where = where;
4333 rc = acl_check_internal(where, addr, s, 0, user_msgptr, log_msgptr);
4334 acl_where = ACL_WHERE_UNKNOWN;
4335
4336 /* Cutthrough - if requested,
4337 and WHERE_RCPT and not yet opened conn as result of recipient-verify,
4338 and rcpt acl returned accept,
4339 and first recipient (cancel on any subsequents)
4340 open one now and run it up to RCPT acceptance.
4341 A failed verify should cancel cutthrough request.
4342
4343 Initial implementation: dual-write to spool.
4344 Assume the rxd datastream is now being copied byte-for-byte to an open cutthrough connection.
4345
4346 Cease cutthrough copy on rxd final dot; do not send one.
4347
4348 On a data acl, if not accept and a cutthrough conn is open, hard-close it (no SMTP niceness).
4349
4350 On data acl accept, terminate the dataphase on an open cutthrough conn. If accepted or
4351 perm-rejected, reflect that to the original sender - and dump the spooled copy.
4352 If temp-reject, close the conn (and keep the spooled copy).
4353 If conn-failure, no action (and keep the spooled copy).
4354 */
4355 switch (where)
4356 {
4357 case ACL_WHERE_RCPT:
4358 #ifdef EXPERIMENTAL_PRDR
4359 case ACL_WHERE_PRDR:
4360 #endif
4361 if( rcpt_count > 1 )
4362 cancel_cutthrough_connection("more than one recipient");
4363 else if (rc == OK && cutthrough_delivery && cutthrough_fd < 0)
4364 open_cutthrough_connection(addr);
4365 break;
4366
4367 case ACL_WHERE_PREDATA:
4368 if( rc == OK )
4369 cutthrough_predata();
4370 else
4371 cancel_cutthrough_connection("predata acl not ok");
4372 break;
4373
4374 case ACL_WHERE_QUIT:
4375 case ACL_WHERE_NOTQUIT:
4376 cancel_cutthrough_connection("quit or notquit");
4377 break;
4378
4379 default:
4380 break;
4381 }
4382
4383 deliver_domain = deliver_localpart = deliver_address_data =
4384 sender_address_data = NULL;
4385
4386 /* A DISCARD response is permitted only for message ACLs, excluding the PREDATA
4387 ACL, which is really in the middle of an SMTP command. */
4388
4389 if (rc == DISCARD)
4390 {
4391 if (where > ACL_WHERE_NOTSMTP || where == ACL_WHERE_PREDATA)
4392 {
4393 log_write(0, LOG_MAIN|LOG_PANIC, "\"discard\" verb not allowed in %s "
4394 "ACL", acl_wherenames[where]);
4395 return ERROR;
4396 }
4397 return DISCARD;
4398 }
4399
4400 /* A DROP response is not permitted from MAILAUTH */
4401
4402 if (rc == FAIL_DROP && where == ACL_WHERE_MAILAUTH)
4403 {
4404 log_write(0, LOG_MAIN|LOG_PANIC, "\"drop\" verb not allowed in %s "
4405 "ACL", acl_wherenames[where]);
4406 return ERROR;
4407 }
4408
4409 /* Before giving a response, take a look at the length of any user message, and
4410 split it up into multiple lines if possible. */
4411
4412 *user_msgptr = string_split_message(*user_msgptr);
4413 if (fake_response != OK)
4414 fake_response_text = string_split_message(fake_response_text);
4415
4416 return rc;
4417 }
4418
4419
4420 /*************************************************
4421 * Create ACL variable *
4422 *************************************************/
4423
4424 /* Create an ACL variable or reuse an existing one. ACL variables are in a
4425 binary tree (see tree.c) with acl_var_c and acl_var_m as root nodes.
4426
4427 Argument:
4428 name pointer to the variable's name, starting with c or m
4429
4430 Returns the pointer to variable's tree node
4431 */
4432
4433 tree_node *
4434 acl_var_create(uschar *name)
4435 {
4436 tree_node *node, **root;
4437 root = (name[0] == 'c')? &acl_var_c : &acl_var_m;
4438 node = tree_search(*root, name);
4439 if (node == NULL)
4440 {
4441 node = store_get(sizeof(tree_node) + Ustrlen(name));
4442 Ustrcpy(node->name, name);
4443 (void)tree_insertnode(root, node);
4444 }
4445 node->data.ptr = NULL;
4446 return node;
4447 }
4448
4449
4450
4451 /*************************************************
4452 * Write an ACL variable in spool format *
4453 *************************************************/
4454
4455 /* This function is used as a callback for tree_walk when writing variables to
4456 the spool file. To retain spool file compatibility, what is written is -aclc or
4457 -aclm followed by the rest of the name and the data length, space separated,
4458 then the value itself, starting on a new line, and terminated by an additional
4459 newline. When we had only numbered ACL variables, the first line might look
4460 like this: "-aclc 5 20". Now it might be "-aclc foo 20" for the variable called
4461 acl_cfoo.
4462
4463 Arguments:
4464 name of the variable
4465 value of the variable
4466 ctx FILE pointer (as a void pointer)
4467
4468 Returns: nothing
4469 */
4470
4471 void
4472 acl_var_write(uschar *name, uschar *value, void *ctx)
4473 {
4474 FILE *f = (FILE *)ctx;
4475 fprintf(f, "-acl%c %s %d\n%s\n", name[0], name+1, Ustrlen(value), value);
4476 }
4477
4478 /* End of acl.c */