Fix Solaris build
[exim.git] / src / src / acl.c
1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
4
5 /* Copyright (c) University of Cambridge 1995 - 2016 */
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 #ifndef DISABLE_DKIM
69 ACLC_DKIM_SIGNER,
70 ACLC_DKIM_STATUS,
71 #endif
72 #ifdef EXPERIMENTAL_DMARC
73 ACLC_DMARC_STATUS,
74 #endif
75 ACLC_DNSLISTS,
76 ACLC_DOMAINS,
77 ACLC_ENCRYPTED,
78 ACLC_ENDPASS,
79 ACLC_HOSTS,
80 ACLC_LOCAL_PARTS,
81 ACLC_LOG_MESSAGE,
82 ACLC_LOG_REJECT_TARGET,
83 ACLC_LOGWRITE,
84 #ifdef WITH_CONTENT_SCAN
85 ACLC_MALWARE,
86 #endif
87 ACLC_MESSAGE,
88 #ifdef WITH_CONTENT_SCAN
89 ACLC_MIME_REGEX,
90 #endif
91 ACLC_RATELIMIT,
92 ACLC_RECIPIENTS,
93 #ifdef WITH_CONTENT_SCAN
94 ACLC_REGEX,
95 #endif
96 ACLC_REMOVE_HEADER,
97 ACLC_SENDER_DOMAINS,
98 ACLC_SENDERS,
99 ACLC_SET,
100 #ifdef WITH_CONTENT_SCAN
101 ACLC_SPAM,
102 #endif
103 #ifdef EXPERIMENTAL_SPF
104 ACLC_SPF,
105 ACLC_SPF_GUESS,
106 #endif
107 ACLC_UDPSEND,
108 ACLC_VERIFY };
109
110 /* ACL conditions/modifiers: "delay", "control", "continue", "endpass",
111 "message", "log_message", "log_reject_target", "logwrite", and "set" are
112 modifiers that look like conditions but always return TRUE. They are used for
113 their side effects. */
114
115 static uschar *conditions[] = {
116 US"acl",
117 US"add_header",
118 US"authenticated",
119 #ifdef EXPERIMENTAL_BRIGHTMAIL
120 US"bmi_optin",
121 #endif
122 US"condition",
123 US"continue",
124 US"control",
125 #ifdef EXPERIMENTAL_DCC
126 US"dcc",
127 #endif
128 #ifdef WITH_CONTENT_SCAN
129 US"decode",
130 #endif
131 US"delay",
132 #ifndef DISABLE_DKIM
133 US"dkim_signers",
134 US"dkim_status",
135 #endif
136 #ifdef EXPERIMENTAL_DMARC
137 US"dmarc_status",
138 #endif
139 US"dnslists",
140 US"domains",
141 US"encrypted",
142 US"endpass",
143 US"hosts",
144 US"local_parts",
145 US"log_message",
146 US"log_reject_target",
147 US"logwrite",
148 #ifdef WITH_CONTENT_SCAN
149 US"malware",
150 #endif
151 US"message",
152 #ifdef WITH_CONTENT_SCAN
153 US"mime_regex",
154 #endif
155 US"ratelimit",
156 US"recipients",
157 #ifdef WITH_CONTENT_SCAN
158 US"regex",
159 #endif
160 US"remove_header",
161 US"sender_domains", US"senders", US"set",
162 #ifdef WITH_CONTENT_SCAN
163 US"spam",
164 #endif
165 #ifdef EXPERIMENTAL_SPF
166 US"spf",
167 US"spf_guess",
168 #endif
169 US"udpsend",
170 US"verify" };
171
172
173 /* Return values from decode_control(); keep in step with the table of names
174 that follows! */
175
176 enum {
177 CONTROL_AUTH_UNADVERTISED,
178 #ifdef EXPERIMENTAL_BRIGHTMAIL
179 CONTROL_BMI_RUN,
180 #endif
181 CONTROL_DEBUG,
182 #ifndef DISABLE_DKIM
183 CONTROL_DKIM_VERIFY,
184 #endif
185 #ifdef EXPERIMENTAL_DMARC
186 CONTROL_DMARC_VERIFY,
187 CONTROL_DMARC_FORENSIC,
188 #endif
189 CONTROL_DSCP,
190 CONTROL_ERROR,
191 CONTROL_CASEFUL_LOCAL_PART,
192 CONTROL_CASELOWER_LOCAL_PART,
193 CONTROL_CUTTHROUGH_DELIVERY,
194 CONTROL_ENFORCE_SYNC,
195 CONTROL_NO_ENFORCE_SYNC,
196 CONTROL_FREEZE,
197 CONTROL_QUEUE_ONLY,
198 CONTROL_SUBMISSION,
199 CONTROL_SUPPRESS_LOCAL_FIXUPS,
200 #ifdef WITH_CONTENT_SCAN
201 CONTROL_NO_MBOX_UNSPOOL,
202 #endif
203 CONTROL_FAKEDEFER,
204 CONTROL_FAKEREJECT,
205 #ifdef SUPPORT_I18N
206 CONTROL_UTF8_DOWNCONVERT,
207 #endif
208 CONTROL_NO_MULTILINE,
209 CONTROL_NO_PIPELINING,
210 CONTROL_NO_DELAY_FLUSH,
211 CONTROL_NO_CALLOUT_FLUSH
212 };
213
214 /* ACL control names; keep in step with the table above! This list is used for
215 turning ids into names. The actual list of recognized names is in the variable
216 control_def controls_list[] below. The fact that there are two lists is a mess
217 and should be tidied up. */
218
219 static uschar *controls[] = {
220 US"allow_auth_unadvertised",
221 #ifdef EXPERIMENTAL_BRIGHTMAIL
222 US"bmi_run",
223 #endif
224 US"debug",
225 #ifndef DISABLE_DKIM
226 US"dkim_disable_verify",
227 #endif
228 #ifdef EXPERIMENTAL_DMARC
229 US"dmarc_disable_verify",
230 US"dmarc_enable_forensic",
231 #endif
232 US"dscp",
233 US"error",
234 US"caseful_local_part",
235 US"caselower_local_part",
236 US"cutthrough_delivery",
237 US"enforce_sync",
238 US"no_enforce_sync",
239 US"freeze",
240 US"queue_only",
241 US"submission",
242 US"suppress_local_fixups",
243 #ifdef WITH_CONTENT_SCAN
244 US"no_mbox_unspool",
245 #endif
246 US"fakedefer",
247 US"fakereject",
248 #ifdef SUPPORT_I18N
249 US"utf8_downconvert",
250 #endif
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 #ifndef DISABLE_DKIM
279 TRUE, /* dkim_signers */
280 TRUE, /* dkim_status */
281 #endif
282 #ifdef EXPERIMENTAL_DMARC
283 TRUE, /* dmarc_status */
284 #endif
285 TRUE, /* dnslists */
286 FALSE, /* domains */
287 FALSE, /* encrypted */
288 TRUE, /* endpass */
289 FALSE, /* hosts */
290 FALSE, /* local_parts */
291 TRUE, /* log_message */
292 TRUE, /* log_reject_target */
293 TRUE, /* logwrite */
294 #ifdef WITH_CONTENT_SCAN
295 TRUE, /* malware */
296 #endif
297 TRUE, /* message */
298 #ifdef WITH_CONTENT_SCAN
299 TRUE, /* mime_regex */
300 #endif
301 TRUE, /* ratelimit */
302 FALSE, /* recipients */
303 #ifdef WITH_CONTENT_SCAN
304 TRUE, /* regex */
305 #endif
306 TRUE, /* remove_header */
307 FALSE, /* sender_domains */
308 FALSE, /* senders */
309 TRUE, /* set */
310 #ifdef WITH_CONTENT_SCAN
311 TRUE, /* spam */
312 #endif
313 #ifdef EXPERIMENTAL_SPF
314 TRUE, /* spf */
315 TRUE, /* spf_guess */
316 #endif
317 TRUE, /* udpsend */
318 TRUE /* verify */
319 };
320
321 /* Flags to identify the modifiers */
322
323 static uschar cond_modifiers[] = {
324 FALSE, /* acl */
325 TRUE, /* add_header */
326 FALSE, /* authenticated */
327 #ifdef EXPERIMENTAL_BRIGHTMAIL
328 TRUE, /* bmi_optin */
329 #endif
330 FALSE, /* condition */
331 TRUE, /* continue */
332 TRUE, /* control */
333 #ifdef EXPERIMENTAL_DCC
334 FALSE, /* dcc */
335 #endif
336 #ifdef WITH_CONTENT_SCAN
337 FALSE, /* decode */
338 #endif
339 TRUE, /* delay */
340 #ifndef DISABLE_DKIM
341 FALSE, /* dkim_signers */
342 FALSE, /* dkim_status */
343 #endif
344 #ifdef EXPERIMENTAL_DMARC
345 FALSE, /* dmarc_status */
346 #endif
347 FALSE, /* dnslists */
348 FALSE, /* domains */
349 FALSE, /* encrypted */
350 TRUE, /* endpass */
351 FALSE, /* hosts */
352 FALSE, /* local_parts */
353 TRUE, /* log_message */
354 TRUE, /* log_reject_target */
355 TRUE, /* logwrite */
356 #ifdef WITH_CONTENT_SCAN
357 FALSE, /* malware */
358 #endif
359 TRUE, /* message */
360 #ifdef WITH_CONTENT_SCAN
361 FALSE, /* mime_regex */
362 #endif
363 FALSE, /* ratelimit */
364 FALSE, /* recipients */
365 #ifdef WITH_CONTENT_SCAN
366 FALSE, /* regex */
367 #endif
368 TRUE, /* remove_header */
369 FALSE, /* sender_domains */
370 FALSE, /* senders */
371 TRUE, /* set */
372 #ifdef WITH_CONTENT_SCAN
373 FALSE, /* spam */
374 #endif
375 #ifdef EXPERIMENTAL_SPF
376 FALSE, /* spf */
377 FALSE, /* spf_guess */
378 #endif
379 TRUE, /* udpsend */
380 FALSE /* verify */
381 };
382
383 /* Bit map vector of which conditions and modifiers are not allowed at certain
384 times. For each condition and modifier, there's a bitmap of dis-allowed times.
385 For some, it is easier to specify the negation of a small number of allowed
386 times. */
387
388 static unsigned int cond_forbids[] = {
389 0, /* acl */
390
391 (unsigned int)
392 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* add_header */
393 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
394 #ifndef DISABLE_PRDR
395 (1<<ACL_WHERE_PRDR)|
396 #endif
397 (1<<ACL_WHERE_MIME)|(1<<ACL_WHERE_NOTSMTP)|
398 (1<<ACL_WHERE_DKIM)|
399 (1<<ACL_WHERE_NOTSMTP_START)),
400
401 (1<<ACL_WHERE_NOTSMTP)| /* authenticated */
402 (1<<ACL_WHERE_NOTSMTP_START)|
403 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO),
404
405 #ifdef EXPERIMENTAL_BRIGHTMAIL
406 (1<<ACL_WHERE_AUTH)| /* bmi_optin */
407 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
408 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_MIME)|
409 #ifndef DISABLE_PRDR
410 (1<<ACL_WHERE_PRDR)|
411 #endif
412 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
413 (1<<ACL_WHERE_MAILAUTH)|
414 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
415 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_PREDATA)|
416 (1<<ACL_WHERE_NOTSMTP_START),
417 #endif
418
419 0, /* condition */
420
421 0, /* continue */
422
423 /* Certain types of control are always allowed, so we let it through
424 always and check in the control processing itself. */
425
426 0, /* control */
427
428 #ifdef EXPERIMENTAL_DCC
429 (unsigned int)
430 ~((1<<ACL_WHERE_DATA)| /* dcc */
431 #ifndef DISABLE_PRDR
432 (1<<ACL_WHERE_PRDR)|
433 #endif
434 (1<<ACL_WHERE_NOTSMTP)),
435 #endif
436
437 #ifdef WITH_CONTENT_SCAN
438 (unsigned int)
439 ~(1<<ACL_WHERE_MIME), /* decode */
440 #endif
441
442 (1<<ACL_WHERE_NOTQUIT), /* delay */
443
444 #ifndef DISABLE_DKIM
445 (unsigned int)
446 ~(1<<ACL_WHERE_DKIM), /* dkim_signers */
447
448 (unsigned int)
449 ~(1<<ACL_WHERE_DKIM), /* dkim_status */
450 #endif
451
452 #ifdef EXPERIMENTAL_DMARC
453 (unsigned int)
454 ~(1<<ACL_WHERE_DATA), /* dmarc_status */
455 #endif
456
457 /* Explicit key lookups can be made in non-smtp ACLs so pass
458 always and check in the verify processing itself. */
459
460 0, /* dnslists */
461
462 (unsigned int)
463 ~((1<<ACL_WHERE_RCPT) /* domains */
464 |(1<<ACL_WHERE_VRFY)
465 #ifndef DISABLE_PRDR
466 |(1<<ACL_WHERE_PRDR)
467 #endif
468 ),
469
470 (1<<ACL_WHERE_NOTSMTP)| /* encrypted */
471 (1<<ACL_WHERE_CONNECT)|
472 (1<<ACL_WHERE_NOTSMTP_START)|
473 (1<<ACL_WHERE_HELO),
474
475 0, /* endpass */
476
477 (1<<ACL_WHERE_NOTSMTP)| /* hosts */
478 (1<<ACL_WHERE_NOTSMTP_START),
479
480 (unsigned int)
481 ~((1<<ACL_WHERE_RCPT) /* local_parts */
482 |(1<<ACL_WHERE_VRFY)
483 #ifndef DISABLE_PRDR
484 |(1<<ACL_WHERE_PRDR)
485 #endif
486 ),
487
488 0, /* log_message */
489
490 0, /* log_reject_target */
491
492 0, /* logwrite */
493
494 #ifdef WITH_CONTENT_SCAN
495 (unsigned int)
496 ~((1<<ACL_WHERE_DATA)| /* malware */
497 #ifndef DISABLE_PRDR
498 (1<<ACL_WHERE_PRDR)|
499 #endif
500 (1<<ACL_WHERE_NOTSMTP)),
501 #endif
502
503 0, /* message */
504
505 #ifdef WITH_CONTENT_SCAN
506 (unsigned int)
507 ~(1<<ACL_WHERE_MIME), /* mime_regex */
508 #endif
509
510 0, /* ratelimit */
511
512 (unsigned int)
513 ~(1<<ACL_WHERE_RCPT), /* recipients */
514
515 #ifdef WITH_CONTENT_SCAN
516 (unsigned int)
517 ~((1<<ACL_WHERE_DATA)| /* regex */
518 #ifndef DISABLE_PRDR
519 (1<<ACL_WHERE_PRDR)|
520 #endif
521 (1<<ACL_WHERE_NOTSMTP)|
522 (1<<ACL_WHERE_MIME)),
523 #endif
524
525 (unsigned int)
526 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* remove_header */
527 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
528 #ifndef DISABLE_PRDR
529 (1<<ACL_WHERE_PRDR)|
530 #endif
531 (1<<ACL_WHERE_MIME)|(1<<ACL_WHERE_NOTSMTP)|
532 (1<<ACL_WHERE_NOTSMTP_START)),
533
534 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* sender_domains */
535 (1<<ACL_WHERE_HELO)|
536 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
537 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
538 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
539
540 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* senders */
541 (1<<ACL_WHERE_HELO)|
542 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
543 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
544 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
545
546 0, /* set */
547
548 #ifdef WITH_CONTENT_SCAN
549 (unsigned int)
550 ~((1<<ACL_WHERE_DATA)| /* spam */
551 #ifndef DISABLE_PRDR
552 (1<<ACL_WHERE_PRDR)|
553 #endif
554 (1<<ACL_WHERE_NOTSMTP)),
555 #endif
556
557 #ifdef EXPERIMENTAL_SPF
558 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* spf */
559 (1<<ACL_WHERE_HELO)|
560 (1<<ACL_WHERE_MAILAUTH)|
561 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
562 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY)|
563 (1<<ACL_WHERE_NOTSMTP)|
564 (1<<ACL_WHERE_NOTSMTP_START),
565
566 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* spf_guess */
567 (1<<ACL_WHERE_HELO)|
568 (1<<ACL_WHERE_MAILAUTH)|
569 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
570 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY)|
571 (1<<ACL_WHERE_NOTSMTP)|
572 (1<<ACL_WHERE_NOTSMTP_START),
573 #endif
574
575 0, /* udpsend */
576
577 /* Certain types of verify are always allowed, so we let it through
578 always and check in the verify function itself */
579
580 0 /* verify */
581 };
582
583
584 /* Bit map vector of which controls are not allowed at certain times. For
585 each control, there's a bitmap of dis-allowed times. For some, it is easier to
586 specify the negation of a small number of allowed times. */
587
588 static unsigned int control_forbids[] = {
589 (unsigned int)
590 ~((1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)), /* allow_auth_unadvertised */
591
592 #ifdef EXPERIMENTAL_BRIGHTMAIL
593 0, /* bmi_run */
594 #endif
595
596 0, /* debug */
597
598 #ifndef DISABLE_DKIM
599 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* dkim_disable_verify */
600 # ifndef DISABLE_PRDR
601 (1<<ACL_WHERE_PRDR)|
602 # endif
603 (1<<ACL_WHERE_NOTSMTP_START),
604 #endif
605
606 #ifdef EXPERIMENTAL_DMARC
607 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* dmarc_disable_verify */
608 (1<<ACL_WHERE_NOTSMTP_START),
609 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* dmarc_enable_forensic */
610 (1<<ACL_WHERE_NOTSMTP_START),
611 #endif
612
613 (1<<ACL_WHERE_NOTSMTP)|
614 (1<<ACL_WHERE_NOTSMTP_START)|
615 (1<<ACL_WHERE_NOTQUIT), /* dscp */
616
617 0, /* error */
618
619 (unsigned int)
620 ~(1<<ACL_WHERE_RCPT), /* caseful_local_part */
621
622 (unsigned int)
623 ~(1<<ACL_WHERE_RCPT), /* caselower_local_part */
624
625 (unsigned int)
626 0, /* cutthrough_delivery */
627
628 (1<<ACL_WHERE_NOTSMTP)| /* enforce_sync */
629 (1<<ACL_WHERE_NOTSMTP_START),
630
631 (1<<ACL_WHERE_NOTSMTP)| /* no_enforce_sync */
632 (1<<ACL_WHERE_NOTSMTP_START),
633
634 (unsigned int)
635 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* freeze */
636 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
637 // (1<<ACL_WHERE_PRDR)| /* Not allow one user to freeze for all */
638 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)),
639
640 (unsigned int)
641 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* queue_only */
642 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
643 // (1<<ACL_WHERE_PRDR)| /* Not allow one user to freeze for all */
644 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)),
645
646 (unsigned int)
647 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* submission */
648 (1<<ACL_WHERE_PREDATA)),
649
650 (unsigned int)
651 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* suppress_local_fixups */
652 (1<<ACL_WHERE_PREDATA)|
653 (1<<ACL_WHERE_NOTSMTP_START)),
654
655 #ifdef WITH_CONTENT_SCAN
656 (unsigned int)
657 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* no_mbox_unspool */
658 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
659 // (1<<ACL_WHERE_PRDR)| /* Not allow one user to freeze for all */
660 (1<<ACL_WHERE_MIME)),
661 #endif
662
663 (unsigned int)
664 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakedefer */
665 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
666 #ifndef DISABLE_PRDR
667 (1<<ACL_WHERE_PRDR)|
668 #endif
669 (1<<ACL_WHERE_MIME)),
670
671 (unsigned int)
672 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakereject */
673 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
674 #ifndef DISABLE_PRDR
675 (1<<ACL_WHERE_PRDR)|
676 #endif
677 (1<<ACL_WHERE_MIME)),
678
679 #ifdef SUPPORT_I18N
680 0, /* utf8_downconvert */
681 #endif
682
683 (1<<ACL_WHERE_NOTSMTP)| /* no_multiline */
684 (1<<ACL_WHERE_NOTSMTP_START),
685
686 (1<<ACL_WHERE_NOTSMTP)| /* no_pipelining */
687 (1<<ACL_WHERE_NOTSMTP_START),
688
689 (1<<ACL_WHERE_NOTSMTP)| /* no_delay_flush */
690 (1<<ACL_WHERE_NOTSMTP_START),
691
692 (1<<ACL_WHERE_NOTSMTP)| /* no_callout_flush */
693 (1<<ACL_WHERE_NOTSMTP_START)
694 };
695
696 /* Structure listing various control arguments, with their characteristics. */
697
698 typedef struct control_def {
699 uschar *name;
700 int value; /* CONTROL_xxx value */
701 BOOL has_option; /* Has /option(s) following */
702 } control_def;
703
704 static control_def controls_list[] = {
705 { US"allow_auth_unadvertised", CONTROL_AUTH_UNADVERTISED, FALSE },
706 #ifdef EXPERIMENTAL_BRIGHTMAIL
707 { US"bmi_run", CONTROL_BMI_RUN, FALSE },
708 #endif
709 { US"debug", CONTROL_DEBUG, TRUE },
710 #ifndef DISABLE_DKIM
711 { US"dkim_disable_verify", CONTROL_DKIM_VERIFY, FALSE },
712 #endif
713 #ifdef EXPERIMENTAL_DMARC
714 { US"dmarc_disable_verify", CONTROL_DMARC_VERIFY, FALSE },
715 { US"dmarc_enable_forensic", CONTROL_DMARC_FORENSIC, FALSE },
716 #endif
717 { US"dscp", CONTROL_DSCP, TRUE },
718 { US"caseful_local_part", CONTROL_CASEFUL_LOCAL_PART, FALSE },
719 { US"caselower_local_part", CONTROL_CASELOWER_LOCAL_PART, FALSE },
720 { US"enforce_sync", CONTROL_ENFORCE_SYNC, FALSE },
721 { US"freeze", CONTROL_FREEZE, TRUE },
722 { US"no_callout_flush", CONTROL_NO_CALLOUT_FLUSH, FALSE },
723 { US"no_delay_flush", CONTROL_NO_DELAY_FLUSH, FALSE },
724 { US"no_enforce_sync", CONTROL_NO_ENFORCE_SYNC, FALSE },
725 { US"no_multiline_responses", CONTROL_NO_MULTILINE, FALSE },
726 { US"no_pipelining", CONTROL_NO_PIPELINING, FALSE },
727 { US"queue_only", CONTROL_QUEUE_ONLY, FALSE },
728 #ifdef WITH_CONTENT_SCAN
729 { US"no_mbox_unspool", CONTROL_NO_MBOX_UNSPOOL, FALSE },
730 #endif
731 { US"fakedefer", CONTROL_FAKEDEFER, TRUE },
732 { US"fakereject", CONTROL_FAKEREJECT, TRUE },
733 { US"submission", CONTROL_SUBMISSION, TRUE },
734 { US"suppress_local_fixups", CONTROL_SUPPRESS_LOCAL_FIXUPS, FALSE },
735 { US"cutthrough_delivery", CONTROL_CUTTHROUGH_DELIVERY, FALSE },
736 #ifdef SUPPORT_I18N
737 { US"utf8_downconvert", CONTROL_UTF8_DOWNCONVERT, TRUE }
738 #endif
739 };
740
741 /* Support data structures for Client SMTP Authorization. acl_verify_csa()
742 caches its result in a tree to avoid repeated DNS queries. The result is an
743 integer code which is used as an index into the following tables of
744 explanatory strings and verification return codes. */
745
746 static tree_node *csa_cache = NULL;
747
748 enum { CSA_UNKNOWN, CSA_OK, CSA_DEFER_SRV, CSA_DEFER_ADDR,
749 CSA_FAIL_EXPLICIT, CSA_FAIL_DOMAIN, CSA_FAIL_NOADDR, CSA_FAIL_MISMATCH };
750
751 /* The acl_verify_csa() return code is translated into an acl_verify() return
752 code using the following table. It is OK unless the client is definitely not
753 authorized. This is because CSA is supposed to be optional for sending sites,
754 so recipients should not be too strict about checking it - especially because
755 DNS problems are quite likely to occur. It's possible to use $csa_status in
756 further ACL conditions to distinguish ok, unknown, and defer if required, but
757 the aim is to make the usual configuration simple. */
758
759 static int csa_return_code[] = {
760 OK, OK, OK, OK,
761 FAIL, FAIL, FAIL, FAIL
762 };
763
764 static uschar *csa_status_string[] = {
765 US"unknown", US"ok", US"defer", US"defer",
766 US"fail", US"fail", US"fail", US"fail"
767 };
768
769 static uschar *csa_reason_string[] = {
770 US"unknown",
771 US"ok",
772 US"deferred (SRV lookup failed)",
773 US"deferred (target address lookup failed)",
774 US"failed (explicit authorization required)",
775 US"failed (host name not authorized)",
776 US"failed (no authorized addresses)",
777 US"failed (client address mismatch)"
778 };
779
780 /* Options for the ratelimit condition. Note that there are two variants of
781 the per_rcpt option, depending on the ACL that is used to measure the rate.
782 However any ACL must be able to look up per_rcpt rates in /noupdate mode,
783 so the two variants must have the same internal representation as well as
784 the same configuration string. */
785
786 enum {
787 RATE_PER_WHAT, RATE_PER_CLASH, RATE_PER_ADDR, RATE_PER_BYTE, RATE_PER_CMD,
788 RATE_PER_CONN, RATE_PER_MAIL, RATE_PER_RCPT, RATE_PER_ALLRCPTS
789 };
790
791 #define RATE_SET(var,new) \
792 (((var) == RATE_PER_WHAT) ? ((var) = RATE_##new) : ((var) = RATE_PER_CLASH))
793
794 static uschar *ratelimit_option_string[] = {
795 US"?", US"!", US"per_addr", US"per_byte", US"per_cmd",
796 US"per_conn", US"per_mail", US"per_rcpt", US"per_rcpt"
797 };
798
799 /* Enable recursion between acl_check_internal() and acl_check_condition() */
800
801 static int acl_check_wargs(int, address_item *, const uschar *, int, uschar **,
802 uschar **);
803
804
805 /*************************************************
806 * Pick out name from list *
807 *************************************************/
808
809 /* Use a binary chop method
810
811 Arguments:
812 name name to find
813 list list of names
814 end size of list
815
816 Returns: offset in list, or -1 if not found
817 */
818
819 static int
820 acl_checkname(uschar *name, uschar **list, int end)
821 {
822 int start = 0;
823
824 while (start < end)
825 {
826 int mid = (start + end)/2;
827 int c = Ustrcmp(name, list[mid]);
828 if (c == 0) return mid;
829 if (c < 0) end = mid; else start = mid + 1;
830 }
831
832 return -1;
833 }
834
835
836 /*************************************************
837 * Read and parse one ACL *
838 *************************************************/
839
840 /* This function is called both from readconf in order to parse the ACLs in the
841 configuration file, and also when an ACL is encountered dynamically (e.g. as
842 the result of an expansion). It is given a function to call in order to
843 retrieve the lines of the ACL. This function handles skipping comments and
844 blank lines (where relevant).
845
846 Arguments:
847 func function to get next line of ACL
848 error where to put an error message
849
850 Returns: pointer to ACL, or NULL
851 NULL can be legal (empty ACL); in this case error will be NULL
852 */
853
854 acl_block *
855 acl_read(uschar *(*func)(void), uschar **error)
856 {
857 acl_block *yield = NULL;
858 acl_block **lastp = &yield;
859 acl_block *this = NULL;
860 acl_condition_block *cond;
861 acl_condition_block **condp = NULL;
862 uschar *s;
863
864 *error = NULL;
865
866 while ((s = (*func)()) != NULL)
867 {
868 int v, c;
869 BOOL negated = FALSE;
870 uschar *saveline = s;
871 uschar name[64];
872
873 /* Conditions (but not verbs) are allowed to be negated by an initial
874 exclamation mark. */
875
876 while (isspace(*s)) s++;
877 if (*s == '!')
878 {
879 negated = TRUE;
880 s++;
881 }
882
883 /* Read the name of a verb or a condition, or the start of a new ACL, which
884 can be started by a name, or by a macro definition. */
885
886 s = readconf_readname(name, sizeof(name), s);
887 if (*s == ':' || (isupper(name[0]) && *s == '=')) return yield;
888
889 /* If a verb is unrecognized, it may be another condition or modifier that
890 continues the previous verb. */
891
892 v = acl_checkname(name, verbs, sizeof(verbs)/sizeof(char *));
893 if (v < 0)
894 {
895 if (this == NULL)
896 {
897 *error = string_sprintf("unknown ACL verb \"%s\" in \"%s\"", name,
898 saveline);
899 return NULL;
900 }
901 }
902
903 /* New verb */
904
905 else
906 {
907 if (negated)
908 {
909 *error = string_sprintf("malformed ACL line \"%s\"", saveline);
910 return NULL;
911 }
912 this = store_get(sizeof(acl_block));
913 *lastp = this;
914 lastp = &(this->next);
915 this->next = NULL;
916 this->verb = v;
917 this->condition = NULL;
918 condp = &(this->condition);
919 if (*s == 0) continue; /* No condition on this line */
920 if (*s == '!')
921 {
922 negated = TRUE;
923 s++;
924 }
925 s = readconf_readname(name, sizeof(name), s); /* Condition name */
926 }
927
928 /* Handle a condition or modifier. */
929
930 c = acl_checkname(name, conditions, sizeof(conditions)/sizeof(char *));
931 if (c < 0)
932 {
933 *error = string_sprintf("unknown ACL condition/modifier in \"%s\"",
934 saveline);
935 return NULL;
936 }
937
938 /* The modifiers may not be negated */
939
940 if (negated && cond_modifiers[c])
941 {
942 *error = string_sprintf("ACL error: negation is not allowed with "
943 "\"%s\"", conditions[c]);
944 return NULL;
945 }
946
947 /* ENDPASS may occur only with ACCEPT or DISCARD. */
948
949 if (c == ACLC_ENDPASS &&
950 this->verb != ACL_ACCEPT &&
951 this->verb != ACL_DISCARD)
952 {
953 *error = string_sprintf("ACL error: \"%s\" is not allowed with \"%s\"",
954 conditions[c], verbs[this->verb]);
955 return NULL;
956 }
957
958 cond = store_get(sizeof(acl_condition_block));
959 cond->next = NULL;
960 cond->type = c;
961 cond->u.negated = negated;
962
963 *condp = cond;
964 condp = &(cond->next);
965
966 /* The "set" modifier is different in that its argument is "name=value"
967 rather than just a value, and we can check the validity of the name, which
968 gives us a variable name to insert into the data block. The original ACL
969 variable names were acl_c0 ... acl_c9 and acl_m0 ... acl_m9. This was
970 extended to 20 of each type, but after that people successfully argued for
971 arbitrary names. In the new scheme, the names must start with acl_c or acl_m.
972 After that, we allow alphanumerics and underscores, but the first character
973 after c or m must be a digit or an underscore. This retains backwards
974 compatibility. */
975
976 if (c == ACLC_SET)
977 {
978 uschar *endptr;
979
980 if (Ustrncmp(s, "acl_c", 5) != 0 &&
981 Ustrncmp(s, "acl_m", 5) != 0)
982 {
983 *error = string_sprintf("invalid variable name after \"set\" in ACL "
984 "modifier \"set %s\" (must start \"acl_c\" or \"acl_m\")", s);
985 return NULL;
986 }
987
988 endptr = s + 5;
989 if (!isdigit(*endptr) && *endptr != '_')
990 {
991 *error = string_sprintf("invalid variable name after \"set\" in ACL "
992 "modifier \"set %s\" (digit or underscore must follow acl_c or acl_m)",
993 s);
994 return NULL;
995 }
996
997 while (*endptr != 0 && *endptr != '=' && !isspace(*endptr))
998 {
999 if (!isalnum(*endptr) && *endptr != '_')
1000 {
1001 *error = string_sprintf("invalid character \"%c\" in variable name "
1002 "in ACL modifier \"set %s\"", *endptr, s);
1003 return NULL;
1004 }
1005 endptr++;
1006 }
1007
1008 cond->u.varname = string_copyn(s + 4, endptr - s - 4);
1009 s = endptr;
1010 while (isspace(*s)) s++;
1011 }
1012
1013 /* For "set", we are now positioned for the data. For the others, only
1014 "endpass" has no data */
1015
1016 if (c != ACLC_ENDPASS)
1017 {
1018 if (*s++ != '=')
1019 {
1020 *error = string_sprintf("\"=\" missing after ACL \"%s\" %s", name,
1021 cond_modifiers[c]? US"modifier" : US"condition");
1022 return NULL;
1023 }
1024 while (isspace(*s)) s++;
1025 cond->arg = string_copy(s);
1026 }
1027 }
1028
1029 return yield;
1030 }
1031
1032
1033
1034 /*************************************************
1035 * Set up added header line(s) *
1036 *************************************************/
1037
1038 /* This function is called by the add_header modifier, and also from acl_warn()
1039 to implement the now-deprecated way of adding header lines using "message" on a
1040 "warn" verb. The argument is treated as a sequence of header lines which are
1041 added to a chain, provided there isn't an identical one already there.
1042
1043 Argument: string of header lines
1044 Returns: nothing
1045 */
1046
1047 static void
1048 setup_header(const uschar *hstring)
1049 {
1050 const uschar *p, *q;
1051 int hlen = Ustrlen(hstring);
1052
1053 /* Ignore any leading newlines */
1054 while (*hstring == '\n') hstring++, hlen--;
1055
1056 /* An empty string does nothing; ensure exactly one final newline. */
1057 if (hlen <= 0) return;
1058 if (hstring[--hlen] != '\n') /* no newline */
1059 q = string_sprintf("%s\n", hstring);
1060 else if (hstring[hlen-1] == '\n') /* double newline */
1061 {
1062 uschar * s = string_copy(hstring);
1063 while(s[--hlen] == '\n')
1064 s[hlen+1] = '\0';
1065 q = s;
1066 }
1067 else
1068 q = hstring;
1069
1070 /* Loop for multiple header lines, taking care about continuations */
1071
1072 for (p = q; *p != 0; )
1073 {
1074 const uschar *s;
1075 uschar * hdr;
1076 int newtype = htype_add_bot;
1077 header_line **hptr = &acl_added_headers;
1078
1079 /* Find next header line within the string */
1080
1081 for (;;)
1082 {
1083 q = Ustrchr(q, '\n'); /* we know there was a newline */
1084 if (*(++q) != ' ' && *q != '\t') break;
1085 }
1086
1087 /* If the line starts with a colon, interpret the instruction for where to
1088 add it. This temporarily sets up a new type. */
1089
1090 if (*p == ':')
1091 {
1092 if (strncmpic(p, US":after_received:", 16) == 0)
1093 {
1094 newtype = htype_add_rec;
1095 p += 16;
1096 }
1097 else if (strncmpic(p, US":at_start_rfc:", 14) == 0)
1098 {
1099 newtype = htype_add_rfc;
1100 p += 14;
1101 }
1102 else if (strncmpic(p, US":at_start:", 10) == 0)
1103 {
1104 newtype = htype_add_top;
1105 p += 10;
1106 }
1107 else if (strncmpic(p, US":at_end:", 8) == 0)
1108 {
1109 newtype = htype_add_bot;
1110 p += 8;
1111 }
1112 while (*p == ' ' || *p == '\t') p++;
1113 }
1114
1115 /* See if this line starts with a header name, and if not, add X-ACL-Warn:
1116 to the front of it. */
1117
1118 for (s = p; s < q - 1; s++)
1119 {
1120 if (*s == ':' || !isgraph(*s)) break;
1121 }
1122
1123 hdr = string_sprintf("%s%.*s", (*s == ':')? "" : "X-ACL-Warn: ", (int) (q - p), p);
1124 hlen = Ustrlen(hdr);
1125
1126 /* See if this line has already been added */
1127
1128 while (*hptr != NULL)
1129 {
1130 if (Ustrncmp((*hptr)->text, hdr, hlen) == 0) break;
1131 hptr = &((*hptr)->next);
1132 }
1133
1134 /* Add if not previously present */
1135
1136 if (*hptr == NULL)
1137 {
1138 header_line *h = store_get(sizeof(header_line));
1139 h->text = hdr;
1140 h->next = NULL;
1141 h->type = newtype;
1142 h->slen = hlen;
1143 *hptr = h;
1144 hptr = &(h->next);
1145 }
1146
1147 /* Advance for next header line within the string */
1148
1149 p = q;
1150 }
1151 }
1152
1153
1154
1155 /*************************************************
1156 * List the added header lines *
1157 *************************************************/
1158 uschar *
1159 fn_hdrs_added(void)
1160 {
1161 uschar * ret = NULL;
1162 header_line * h = acl_added_headers;
1163 uschar * s;
1164 uschar * cp;
1165 int size = 0;
1166 int ptr = 0;
1167
1168 if (!h) return NULL;
1169
1170 do
1171 {
1172 s = h->text;
1173 while ((cp = Ustrchr(s, '\n')) != NULL)
1174 {
1175 if (cp[1] == '\0') break;
1176
1177 /* contains embedded newline; needs doubling */
1178 ret = string_catn(ret, &size, &ptr, s, cp-s+1);
1179 ret = string_catn(ret, &size, &ptr, US"\n", 1);
1180 s = cp+1;
1181 }
1182 /* last bit of header */
1183
1184 ret = string_catn(ret, &size, &ptr, s, cp-s+1); /* newline-sep list */
1185 }
1186 while((h = h->next));
1187
1188 ret[ptr-1] = '\0'; /* overwrite last newline */
1189 return ret;
1190 }
1191
1192
1193 /*************************************************
1194 * Set up removed header line(s) *
1195 *************************************************/
1196
1197 /* This function is called by the remove_header modifier. The argument is
1198 treated as a sequence of header names which are added to a colon separated
1199 list, provided there isn't an identical one already there.
1200
1201 Argument: string of header names
1202 Returns: nothing
1203 */
1204
1205 static void
1206 setup_remove_header(const uschar *hnames)
1207 {
1208 if (*hnames != 0)
1209 acl_removed_headers = acl_removed_headers
1210 ? string_sprintf("%s : %s", acl_removed_headers, hnames)
1211 : string_copy(hnames);
1212 }
1213
1214
1215
1216 /*************************************************
1217 * Handle warnings *
1218 *************************************************/
1219
1220 /* This function is called when a WARN verb's conditions are true. It adds to
1221 the message's headers, and/or writes information to the log. In each case, this
1222 only happens once (per message for headers, per connection for log).
1223
1224 ** NOTE: The header adding action using the "message" setting is historic, and
1225 its use is now deprecated. The new add_header modifier should be used instead.
1226
1227 Arguments:
1228 where ACL_WHERE_xxxx indicating which ACL this is
1229 user_message message for adding to headers
1230 log_message message for logging, if different
1231
1232 Returns: nothing
1233 */
1234
1235 static void
1236 acl_warn(int where, uschar *user_message, uschar *log_message)
1237 {
1238 if (log_message != NULL && log_message != user_message)
1239 {
1240 uschar *text;
1241 string_item *logged;
1242
1243 text = string_sprintf("%s Warning: %s", host_and_ident(TRUE),
1244 string_printing(log_message));
1245
1246 /* If a sender verification has failed, and the log message is "sender verify
1247 failed", add the failure message. */
1248
1249 if (sender_verified_failed != NULL &&
1250 sender_verified_failed->message != NULL &&
1251 strcmpic(log_message, US"sender verify failed") == 0)
1252 text = string_sprintf("%s: %s", text, sender_verified_failed->message);
1253
1254 /* Search previously logged warnings. They are kept in malloc
1255 store so they can be freed at the start of a new message. */
1256
1257 for (logged = acl_warn_logged; logged != NULL; logged = logged->next)
1258 if (Ustrcmp(logged->text, text) == 0) break;
1259
1260 if (logged == NULL)
1261 {
1262 int length = Ustrlen(text) + 1;
1263 log_write(0, LOG_MAIN, "%s", text);
1264 logged = store_malloc(sizeof(string_item) + length);
1265 logged->text = (uschar *)logged + sizeof(string_item);
1266 memcpy(logged->text, text, length);
1267 logged->next = acl_warn_logged;
1268 acl_warn_logged = logged;
1269 }
1270 }
1271
1272 /* If there's no user message, we are done. */
1273
1274 if (user_message == NULL) return;
1275
1276 /* If this isn't a message ACL, we can't do anything with a user message.
1277 Log an error. */
1278
1279 if (where > ACL_WHERE_NOTSMTP)
1280 {
1281 log_write(0, LOG_MAIN|LOG_PANIC, "ACL \"warn\" with \"message\" setting "
1282 "found in a non-message (%s) ACL: cannot specify header lines here: "
1283 "message ignored", acl_wherenames[where]);
1284 return;
1285 }
1286
1287 /* The code for setting up header lines is now abstracted into a separate
1288 function so that it can be used for the add_header modifier as well. */
1289
1290 setup_header(user_message);
1291 }
1292
1293
1294
1295 /*************************************************
1296 * Verify and check reverse DNS *
1297 *************************************************/
1298
1299 /* Called from acl_verify() below. We look up the host name(s) of the client IP
1300 address if this has not yet been done. The host_name_lookup() function checks
1301 that one of these names resolves to an address list that contains the client IP
1302 address, so we don't actually have to do the check here.
1303
1304 Arguments:
1305 user_msgptr pointer for user message
1306 log_msgptr pointer for log message
1307
1308 Returns: OK verification condition succeeded
1309 FAIL verification failed
1310 DEFER there was a problem verifying
1311 */
1312
1313 static int
1314 acl_verify_reverse(uschar **user_msgptr, uschar **log_msgptr)
1315 {
1316 int rc;
1317
1318 user_msgptr = user_msgptr; /* stop compiler warning */
1319
1320 /* Previous success */
1321
1322 if (sender_host_name != NULL) return OK;
1323
1324 /* Previous failure */
1325
1326 if (host_lookup_failed)
1327 {
1328 *log_msgptr = string_sprintf("host lookup failed%s", host_lookup_msg);
1329 return FAIL;
1330 }
1331
1332 /* Need to do a lookup */
1333
1334 HDEBUG(D_acl)
1335 debug_printf("looking up host name to force name/address consistency check\n");
1336
1337 if ((rc = host_name_lookup()) != OK)
1338 {
1339 *log_msgptr = (rc == DEFER)?
1340 US"host lookup deferred for reverse lookup check"
1341 :
1342 string_sprintf("host lookup failed for reverse lookup check%s",
1343 host_lookup_msg);
1344 return rc; /* DEFER or FAIL */
1345 }
1346
1347 host_build_sender_fullhost();
1348 return OK;
1349 }
1350
1351
1352
1353 /*************************************************
1354 * Check client IP address matches CSA target *
1355 *************************************************/
1356
1357 /* Called from acl_verify_csa() below. This routine scans a section of a DNS
1358 response for address records belonging to the CSA target hostname. The section
1359 is specified by the reset argument, either RESET_ADDITIONAL or RESET_ANSWERS.
1360 If one of the addresses matches the client's IP address, then the client is
1361 authorized by CSA. If there are target IP addresses but none of them match
1362 then the client is using an unauthorized IP address. If there are no target IP
1363 addresses then the client cannot be using an authorized IP address. (This is
1364 an odd configuration - why didn't the SRV record have a weight of 1 instead?)
1365
1366 Arguments:
1367 dnsa the DNS answer block
1368 dnss a DNS scan block for us to use
1369 reset option specifing what portion to scan, as described above
1370 target the target hostname to use for matching RR names
1371
1372 Returns: CSA_OK successfully authorized
1373 CSA_FAIL_MISMATCH addresses found but none matched
1374 CSA_FAIL_NOADDR no target addresses found
1375 */
1376
1377 static int
1378 acl_verify_csa_address(dns_answer *dnsa, dns_scan *dnss, int reset,
1379 uschar *target)
1380 {
1381 dns_record *rr;
1382 dns_address *da;
1383
1384 BOOL target_found = FALSE;
1385
1386 for (rr = dns_next_rr(dnsa, dnss, reset);
1387 rr != NULL;
1388 rr = dns_next_rr(dnsa, dnss, RESET_NEXT))
1389 {
1390 /* Check this is an address RR for the target hostname. */
1391
1392 if (rr->type != T_A
1393 #if HAVE_IPV6
1394 && rr->type != T_AAAA
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(const uschar *domain)
1448 {
1449 tree_node *t;
1450 const uschar *found;
1451 uschar *p;
1452 int priority, weight, port;
1453 dns_answer dnsa;
1454 dns_scan dnss;
1455 dns_record *rr;
1456 int rc, type;
1457 uschar target[256];
1458
1459 /* Work out the domain we are using for the CSA lookup. The default is the
1460 client's HELO domain. If the client has not said HELO, use its IP address
1461 instead. If it's a local client (exim -bs), CSA isn't applicable. */
1462
1463 while (isspace(*domain) && *domain != '\0') ++domain;
1464 if (*domain == '\0') domain = sender_helo_name;
1465 if (domain == NULL) domain = sender_host_address;
1466 if (sender_host_address == NULL) return CSA_UNKNOWN;
1467
1468 /* If we have an address literal, strip off the framing ready for turning it
1469 into a domain. The framing consists of matched square brackets possibly
1470 containing a keyword and a colon before the actual IP address. */
1471
1472 if (domain[0] == '[')
1473 {
1474 const uschar *start = Ustrchr(domain, ':');
1475 if (start == NULL) start = domain;
1476 domain = string_copyn(start + 1, Ustrlen(start) - 2);
1477 }
1478
1479 /* Turn domains that look like bare IP addresses into domains in the reverse
1480 DNS. This code also deals with address literals and $sender_host_address. It's
1481 not quite kosher to treat bare domains such as EHLO 192.0.2.57 the same as
1482 address literals, but it's probably the most friendly thing to do. This is an
1483 extension to CSA, so we allow it to be turned off for proper conformance. */
1484
1485 if (string_is_ip_address(domain, NULL) != 0)
1486 {
1487 if (!dns_csa_use_reverse) return CSA_UNKNOWN;
1488 dns_build_reverse(domain, target);
1489 domain = target;
1490 }
1491
1492 /* Find out if we've already done the CSA check for this domain. If we have,
1493 return the same result again. Otherwise build a new cached result structure
1494 for this domain. The name is filled in now, and the value is filled in when
1495 we return from this function. */
1496
1497 t = tree_search(csa_cache, domain);
1498 if (t != NULL) return t->data.val;
1499
1500 t = store_get_perm(sizeof(tree_node) + Ustrlen(domain));
1501 Ustrcpy(t->name, domain);
1502 (void)tree_insertnode(&csa_cache, t);
1503
1504 /* Now we are ready to do the actual DNS lookup(s). */
1505
1506 found = domain;
1507 switch (dns_special_lookup(&dnsa, domain, T_CSA, &found))
1508 {
1509 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1510
1511 default:
1512 return t->data.val = CSA_DEFER_SRV;
1513
1514 /* If we found nothing, the client's authorization is unknown. */
1515
1516 case DNS_NOMATCH:
1517 case DNS_NODATA:
1518 return t->data.val = CSA_UNKNOWN;
1519
1520 /* We got something! Go on to look at the reply in more detail. */
1521
1522 case DNS_SUCCEED:
1523 break;
1524 }
1525
1526 /* Scan the reply for well-formed CSA SRV records. */
1527
1528 for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS);
1529 rr != NULL;
1530 rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT))
1531 {
1532 if (rr->type != T_SRV) continue;
1533
1534 /* Extract the numerical SRV fields (p is incremented) */
1535
1536 p = rr->data;
1537 GETSHORT(priority, p);
1538 GETSHORT(weight, p);
1539 GETSHORT(port, p);
1540
1541 DEBUG(D_acl)
1542 debug_printf("CSA priority=%d weight=%d port=%d\n", priority, weight, port);
1543
1544 /* Check the CSA version number */
1545
1546 if (priority != 1) continue;
1547
1548 /* If the domain does not have a CSA SRV record of its own (i.e. the domain
1549 found by dns_special_lookup() is a parent of the one we asked for), we check
1550 the subdomain assertions in the port field. At the moment there's only one
1551 assertion: legitimate SMTP clients are all explicitly authorized with CSA
1552 SRV records of their own. */
1553
1554 if (Ustrcmp(found, domain) != 0)
1555 {
1556 if (port & 1)
1557 return t->data.val = CSA_FAIL_EXPLICIT;
1558 else
1559 return t->data.val = CSA_UNKNOWN;
1560 }
1561
1562 /* This CSA SRV record refers directly to our domain, so we check the value
1563 in the weight field to work out the domain's authorization. 0 and 1 are
1564 unauthorized; 3 means the client is authorized but we can't check the IP
1565 address in order to authenticate it, so we treat it as unknown; values
1566 greater than 3 are undefined. */
1567
1568 if (weight < 2) return t->data.val = CSA_FAIL_DOMAIN;
1569
1570 if (weight > 2) continue;
1571
1572 /* Weight == 2, which means the domain is authorized. We must check that the
1573 client's IP address is listed as one of the SRV target addresses. Save the
1574 target hostname then break to scan the additional data for its addresses. */
1575
1576 (void)dn_expand(dnsa.answer, dnsa.answer + dnsa.answerlen, p,
1577 (DN_EXPAND_ARG4_TYPE)target, sizeof(target));
1578
1579 DEBUG(D_acl) debug_printf("CSA target is %s\n", target);
1580
1581 break;
1582 }
1583
1584 /* If we didn't break the loop then no appropriate records were found. */
1585
1586 if (rr == NULL) return t->data.val = CSA_UNKNOWN;
1587
1588 /* Do not check addresses if the target is ".", in accordance with RFC 2782.
1589 A target of "." indicates there are no valid addresses, so the client cannot
1590 be authorized. (This is an odd configuration because weight=2 target=. is
1591 equivalent to weight=1, but we check for it in order to keep load off the
1592 root name servers.) Note that dn_expand() turns "." into "". */
1593
1594 if (Ustrcmp(target, "") == 0) return t->data.val = CSA_FAIL_NOADDR;
1595
1596 /* Scan the additional section of the CSA SRV reply for addresses belonging
1597 to the target. If the name server didn't return any additional data (e.g.
1598 because it does not fully support SRV records), we need to do another lookup
1599 to obtain the target addresses; otherwise we have a definitive result. */
1600
1601 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ADDITIONAL, target);
1602 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1603
1604 /* The DNS lookup type corresponds to the IP version used by the client. */
1605
1606 #if HAVE_IPV6
1607 if (Ustrchr(sender_host_address, ':') != NULL)
1608 type = T_AAAA;
1609 else
1610 #endif /* HAVE_IPV6 */
1611 type = T_A;
1612
1613
1614 lookup_dnssec_authenticated = NULL;
1615 switch (dns_lookup(&dnsa, target, type, NULL))
1616 {
1617 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1618
1619 default:
1620 return t->data.val = CSA_DEFER_ADDR;
1621
1622 /* If the query succeeded, scan the addresses and return the result. */
1623
1624 case DNS_SUCCEED:
1625 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ANSWERS, target);
1626 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1627 /* else fall through */
1628
1629 /* If the target has no IP addresses, the client cannot have an authorized
1630 IP address. However, if the target site uses A6 records (not AAAA records)
1631 we have to do yet another lookup in order to check them. */
1632
1633 case DNS_NOMATCH:
1634 case DNS_NODATA:
1635 return t->data.val = CSA_FAIL_NOADDR;
1636 }
1637 }
1638
1639
1640
1641 /*************************************************
1642 * Handle verification (address & other) *
1643 *************************************************/
1644
1645 enum { VERIFY_REV_HOST_LKUP, VERIFY_CERT, VERIFY_HELO, VERIFY_CSA, VERIFY_HDR_SYNTAX,
1646 VERIFY_NOT_BLIND, VERIFY_HDR_SNDR, VERIFY_SNDR, VERIFY_RCPT,
1647 VERIFY_HDR_NAMES_ASCII
1648 };
1649 typedef struct {
1650 uschar * name;
1651 int value;
1652 unsigned where_allowed; /* bitmap */
1653 BOOL no_options; /* Never has /option(s) following */
1654 unsigned alt_opt_sep; /* >0 Non-/ option separator (custom parser) */
1655 } verify_type_t;
1656 static verify_type_t verify_type_list[] = {
1657 { US"reverse_host_lookup", VERIFY_REV_HOST_LKUP, ~0, FALSE, 0 },
1658 { US"certificate", VERIFY_CERT, ~0, TRUE, 0 },
1659 { US"helo", VERIFY_HELO, ~0, TRUE, 0 },
1660 { US"csa", VERIFY_CSA, ~0, FALSE, 0 },
1661 { US"header_syntax", VERIFY_HDR_SYNTAX, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), TRUE, 0 },
1662 { US"not_blind", VERIFY_NOT_BLIND, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), TRUE, 0 },
1663 { US"header_sender", VERIFY_HDR_SNDR, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), FALSE, 0 },
1664 { US"sender", VERIFY_SNDR, (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)
1665 |(1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP),
1666 FALSE, 6 },
1667 { US"recipient", VERIFY_RCPT, (1<<ACL_WHERE_RCPT), FALSE, 0 },
1668 { US"header_names_ascii", VERIFY_HDR_NAMES_ASCII, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), TRUE, 0 }
1669 };
1670
1671
1672 enum { CALLOUT_DEFER_OK, CALLOUT_NOCACHE, CALLOUT_RANDOM, CALLOUT_USE_SENDER,
1673 CALLOUT_USE_POSTMASTER, CALLOUT_POSTMASTER, CALLOUT_FULLPOSTMASTER,
1674 CALLOUT_MAILFROM, CALLOUT_POSTMASTER_MAILFROM, CALLOUT_MAXWAIT, CALLOUT_CONNECT,
1675 CALLOUT_TIME
1676 };
1677 typedef struct {
1678 uschar * name;
1679 int value;
1680 int flag;
1681 BOOL has_option; /* Has =option(s) following */
1682 BOOL timeval; /* Has a time value */
1683 } callout_opt_t;
1684 static callout_opt_t callout_opt_list[] = {
1685 { US"defer_ok", CALLOUT_DEFER_OK, 0, FALSE, FALSE },
1686 { US"no_cache", CALLOUT_NOCACHE, vopt_callout_no_cache, FALSE, FALSE },
1687 { US"random", CALLOUT_RANDOM, vopt_callout_random, FALSE, FALSE },
1688 { US"use_sender", CALLOUT_USE_SENDER, vopt_callout_recipsender, FALSE, FALSE },
1689 { US"use_postmaster", CALLOUT_USE_POSTMASTER,vopt_callout_recippmaster, FALSE, FALSE },
1690 { US"postmaster_mailfrom",CALLOUT_POSTMASTER_MAILFROM,0, TRUE, FALSE },
1691 { US"postmaster", CALLOUT_POSTMASTER, 0, FALSE, FALSE },
1692 { US"fullpostmaster", CALLOUT_FULLPOSTMASTER,vopt_callout_fullpm, FALSE, FALSE },
1693 { US"mailfrom", CALLOUT_MAILFROM, 0, TRUE, FALSE },
1694 { US"maxwait", CALLOUT_MAXWAIT, 0, TRUE, TRUE },
1695 { US"connect", CALLOUT_CONNECT, 0, TRUE, TRUE },
1696 { NULL, CALLOUT_TIME, 0, FALSE, TRUE }
1697 };
1698
1699
1700
1701 /* This function implements the "verify" condition. It is called when
1702 encountered in any ACL, because some tests are almost always permitted. Some
1703 just don't make sense, and always fail (for example, an attempt to test a host
1704 lookup for a non-TCP/IP message). Others are restricted to certain ACLs.
1705
1706 Arguments:
1707 where where called from
1708 addr the recipient address that the ACL is handling, or NULL
1709 arg the argument of "verify"
1710 user_msgptr pointer for user message
1711 log_msgptr pointer for log message
1712 basic_errno where to put verify errno
1713
1714 Returns: OK verification condition succeeded
1715 FAIL verification failed
1716 DEFER there was a problem verifying
1717 ERROR syntax error
1718 */
1719
1720 static int
1721 acl_verify(int where, address_item *addr, const uschar *arg,
1722 uschar **user_msgptr, uschar **log_msgptr, int *basic_errno)
1723 {
1724 int sep = '/';
1725 int callout = -1;
1726 int callout_overall = -1;
1727 int callout_connect = -1;
1728 int verify_options = 0;
1729 int rc;
1730 BOOL verify_header_sender = FALSE;
1731 BOOL defer_ok = FALSE;
1732 BOOL callout_defer_ok = FALSE;
1733 BOOL no_details = FALSE;
1734 BOOL success_on_redirect = FALSE;
1735 address_item *sender_vaddr = NULL;
1736 uschar *verify_sender_address = NULL;
1737 uschar *pm_mailfrom = NULL;
1738 uschar *se_mailfrom = NULL;
1739
1740 /* Some of the verify items have slash-separated options; some do not. Diagnose
1741 an error if options are given for items that don't expect them.
1742 */
1743
1744 uschar *slash = Ustrchr(arg, '/');
1745 const uschar *list = arg;
1746 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
1747 verify_type_t * vp;
1748
1749 if (ss == NULL) goto BAD_VERIFY;
1750
1751 /* Handle name/address consistency verification in a separate function. */
1752
1753 for (vp= verify_type_list;
1754 (char *)vp < (char *)verify_type_list + sizeof(verify_type_list);
1755 vp++
1756 )
1757 if (vp->alt_opt_sep ? strncmpic(ss, vp->name, vp->alt_opt_sep) == 0
1758 : strcmpic (ss, vp->name) == 0)
1759 break;
1760 if ((char *)vp >= (char *)verify_type_list + sizeof(verify_type_list))
1761 goto BAD_VERIFY;
1762
1763 if (vp->no_options && slash != NULL)
1764 {
1765 *log_msgptr = string_sprintf("unexpected '/' found in \"%s\" "
1766 "(this verify item has no options)", arg);
1767 return ERROR;
1768 }
1769 if (!(vp->where_allowed & (1<<where)))
1770 {
1771 *log_msgptr = string_sprintf("cannot verify %s in ACL for %s", vp->name, acl_wherenames[where]);
1772 return ERROR;
1773 }
1774 switch(vp->value)
1775 {
1776 case VERIFY_REV_HOST_LKUP:
1777 if (sender_host_address == NULL) return OK;
1778 if ((rc = acl_verify_reverse(user_msgptr, log_msgptr)) == DEFER)
1779 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size)))
1780 if (strcmpic(ss, US"defer_ok") == 0)
1781 return OK;
1782 return rc;
1783
1784 case VERIFY_CERT:
1785 /* TLS certificate verification is done at STARTTLS time; here we just
1786 test whether it was successful or not. (This is for optional verification; for
1787 mandatory verification, the connection doesn't last this long.) */
1788
1789 if (tls_in.certificate_verified) return OK;
1790 *user_msgptr = US"no verified certificate";
1791 return FAIL;
1792
1793 case VERIFY_HELO:
1794 /* We can test the result of optional HELO verification that might have
1795 occurred earlier. If not, we can attempt the verification now. */
1796
1797 if (!helo_verified && !helo_verify_failed) smtp_verify_helo();
1798 return helo_verified? OK : FAIL;
1799
1800 case VERIFY_CSA:
1801 /* Do Client SMTP Authorization checks in a separate function, and turn the
1802 result code into user-friendly strings. */
1803
1804 rc = acl_verify_csa(list);
1805 *log_msgptr = *user_msgptr = string_sprintf("client SMTP authorization %s",
1806 csa_reason_string[rc]);
1807 csa_status = csa_status_string[rc];
1808 DEBUG(D_acl) debug_printf("CSA result %s\n", csa_status);
1809 return csa_return_code[rc];
1810
1811 case VERIFY_HDR_SYNTAX:
1812 /* Check that all relevant header lines have the correct syntax. If there is
1813 a syntax error, we return details of the error to the sender if configured to
1814 send out full details. (But a "message" setting on the ACL can override, as
1815 always). */
1816
1817 rc = verify_check_headers(log_msgptr);
1818 if (rc != OK && *log_msgptr)
1819 if (smtp_return_error_details)
1820 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1821 else
1822 acl_verify_message = *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 const uschar * sublist = ss;
1914 int optsep = ',';
1915 uschar *opt;
1916 uschar buffer[256];
1917 while (isspace(*sublist)) sublist++;
1918
1919 while ((opt = string_nextinlist(&sublist, &optsep, buffer, sizeof(buffer)))
1920 != NULL)
1921 {
1922 callout_opt_t * op;
1923 double period = 1.0F;
1924
1925 for (op= callout_opt_list; op->name; op++)
1926 if (strncmpic(opt, op->name, Ustrlen(op->name)) == 0)
1927 break;
1928
1929 verify_options |= op->flag;
1930 if (op->has_option)
1931 {
1932 opt += Ustrlen(op->name);
1933 while (isspace(*opt)) opt++;
1934 if (*opt++ != '=')
1935 {
1936 *log_msgptr = string_sprintf("'=' expected after "
1937 "\"%s\" in ACL verify condition \"%s\"", op->name, arg);
1938 return ERROR;
1939 }
1940 while (isspace(*opt)) opt++;
1941 }
1942 if (op->timeval)
1943 {
1944 period = readconf_readtime(opt, 0, FALSE);
1945 if (period < 0)
1946 {
1947 *log_msgptr = string_sprintf("bad time value in ACL condition "
1948 "\"verify %s\"", arg);
1949 return ERROR;
1950 }
1951 }
1952
1953 switch(op->value)
1954 {
1955 case CALLOUT_DEFER_OK: callout_defer_ok = TRUE; break;
1956 case CALLOUT_POSTMASTER: pm_mailfrom = US""; break;
1957 case CALLOUT_FULLPOSTMASTER: pm_mailfrom = US""; break;
1958 case CALLOUT_MAILFROM:
1959 if (!verify_header_sender)
1960 {
1961 *log_msgptr = string_sprintf("\"mailfrom\" is allowed as a "
1962 "callout option only for verify=header_sender (detected in ACL "
1963 "condition \"%s\")", arg);
1964 return ERROR;
1965 }
1966 se_mailfrom = string_copy(opt);
1967 break;
1968 case CALLOUT_POSTMASTER_MAILFROM: pm_mailfrom = string_copy(opt); break;
1969 case CALLOUT_MAXWAIT: callout_overall = period; break;
1970 case CALLOUT_CONNECT: callout_connect = period; break;
1971 case CALLOUT_TIME: callout = period; break;
1972 }
1973 }
1974 }
1975 else
1976 {
1977 *log_msgptr = string_sprintf("'=' expected after \"callout\" in "
1978 "ACL condition \"%s\"", arg);
1979 return ERROR;
1980 }
1981 }
1982 }
1983
1984 /* Option not recognized */
1985
1986 else
1987 {
1988 *log_msgptr = string_sprintf("unknown option \"%s\" in ACL "
1989 "condition \"verify %s\"", ss, arg);
1990 return ERROR;
1991 }
1992 }
1993
1994 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster)) ==
1995 (vopt_callout_recipsender|vopt_callout_recippmaster))
1996 {
1997 *log_msgptr = US"only one of use_sender and use_postmaster can be set "
1998 "for a recipient callout";
1999 return ERROR;
2000 }
2001
2002 /* Handle sender-in-header verification. Default the user message to the log
2003 message if giving out verification details. */
2004
2005 if (verify_header_sender)
2006 {
2007 int verrno;
2008 rc = verify_check_header_address(user_msgptr, log_msgptr, callout,
2009 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, verify_options,
2010 &verrno);
2011 if (rc != OK)
2012 {
2013 *basic_errno = verrno;
2014 if (smtp_return_error_details)
2015 {
2016 if (*user_msgptr == NULL && *log_msgptr != NULL)
2017 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
2018 if (rc == DEFER) acl_temp_details = TRUE;
2019 }
2020 }
2021 }
2022
2023 /* Handle a sender address. The default is to verify *the* sender address, but
2024 optionally a different address can be given, for special requirements. If the
2025 address is empty, we are dealing with a bounce message that has no sender, so
2026 we cannot do any checking. If the real sender address gets rewritten during
2027 verification (e.g. DNS widening), set the flag to stop it being rewritten again
2028 during message reception.
2029
2030 A list of verified "sender" addresses is kept to try to avoid doing to much
2031 work repetitively when there are multiple recipients in a message and they all
2032 require sender verification. However, when callouts are involved, it gets too
2033 complicated because different recipients may require different callout options.
2034 Therefore, we always do a full sender verify when any kind of callout is
2035 specified. Caching elsewhere, for instance in the DNS resolver and in the
2036 callout handling, should ensure that this is not terribly inefficient. */
2037
2038 else if (verify_sender_address != NULL)
2039 {
2040 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster))
2041 != 0)
2042 {
2043 *log_msgptr = US"use_sender or use_postmaster cannot be used for a "
2044 "sender verify callout";
2045 return ERROR;
2046 }
2047
2048 sender_vaddr = verify_checked_sender(verify_sender_address);
2049 if (sender_vaddr != NULL && /* Previously checked */
2050 callout <= 0) /* No callout needed this time */
2051 {
2052 /* If the "routed" flag is set, it means that routing worked before, so
2053 this check can give OK (the saved return code value, if set, belongs to a
2054 callout that was done previously). If the "routed" flag is not set, routing
2055 must have failed, so we use the saved return code. */
2056
2057 if (testflag(sender_vaddr, af_verify_routed)) rc = OK; else
2058 {
2059 rc = sender_vaddr->special_action;
2060 *basic_errno = sender_vaddr->basic_errno;
2061 }
2062 HDEBUG(D_acl) debug_printf("using cached sender verify result\n");
2063 }
2064
2065 /* Do a new verification, and cache the result. The cache is used to avoid
2066 verifying the sender multiple times for multiple RCPTs when callouts are not
2067 specified (see comments above).
2068
2069 The cache is also used on failure to give details in response to the first
2070 RCPT that gets bounced for this reason. However, this can be suppressed by
2071 the no_details option, which sets the flag that says "this detail has already
2072 been sent". The cache normally contains just one address, but there may be
2073 more in esoteric circumstances. */
2074
2075 else
2076 {
2077 BOOL routed = TRUE;
2078 uschar *save_address_data = deliver_address_data;
2079
2080 sender_vaddr = deliver_make_addr(verify_sender_address, TRUE);
2081 #ifdef SUPPORT_I18N
2082 if ((sender_vaddr->prop.utf8_msg = message_smtputf8))
2083 {
2084 sender_vaddr->prop.utf8_downcvt = message_utf8_downconvert == 1;
2085 sender_vaddr->prop.utf8_downcvt_maybe = message_utf8_downconvert == -1;
2086 }
2087 #endif
2088 if (no_details) setflag(sender_vaddr, af_sverify_told);
2089 if (verify_sender_address[0] != 0)
2090 {
2091 /* If this is the real sender address, save the unrewritten version
2092 for use later in receive. Otherwise, set a flag so that rewriting the
2093 sender in verify_address() does not update sender_address. */
2094
2095 if (verify_sender_address == sender_address)
2096 sender_address_unrewritten = sender_address;
2097 else
2098 verify_options |= vopt_fake_sender;
2099
2100 if (success_on_redirect)
2101 verify_options |= vopt_success_on_redirect;
2102
2103 /* The recipient, qualify, and expn options are never set in
2104 verify_options. */
2105
2106 rc = verify_address(sender_vaddr, NULL, verify_options, callout,
2107 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, &routed);
2108
2109 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
2110
2111 if (rc == OK)
2112 {
2113 if (Ustrcmp(sender_vaddr->address, verify_sender_address) != 0)
2114 {
2115 DEBUG(D_acl) debug_printf("sender %s verified ok as %s\n",
2116 verify_sender_address, sender_vaddr->address);
2117 }
2118 else
2119 {
2120 DEBUG(D_acl) debug_printf("sender %s verified ok\n",
2121 verify_sender_address);
2122 }
2123 }
2124 else *basic_errno = sender_vaddr->basic_errno;
2125 }
2126 else rc = OK; /* Null sender */
2127
2128 /* Cache the result code */
2129
2130 if (routed) setflag(sender_vaddr, af_verify_routed);
2131 if (callout > 0) setflag(sender_vaddr, af_verify_callout);
2132 sender_vaddr->special_action = rc;
2133 sender_vaddr->next = sender_verified_list;
2134 sender_verified_list = sender_vaddr;
2135
2136 /* Restore the recipient address data, which might have been clobbered by
2137 the sender verification. */
2138
2139 deliver_address_data = save_address_data;
2140 }
2141
2142 /* Put the sender address_data value into $sender_address_data */
2143
2144 sender_address_data = sender_vaddr->prop.address_data;
2145 }
2146
2147 /* A recipient address just gets a straightforward verify; again we must handle
2148 the DEFER overrides. */
2149
2150 else
2151 {
2152 address_item addr2;
2153
2154 if (success_on_redirect)
2155 verify_options |= vopt_success_on_redirect;
2156
2157 /* We must use a copy of the address for verification, because it might
2158 get rewritten. */
2159
2160 addr2 = *addr;
2161 rc = verify_address(&addr2, NULL, verify_options|vopt_is_recipient, callout,
2162 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, NULL);
2163 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
2164
2165 *basic_errno = addr2.basic_errno;
2166 *log_msgptr = addr2.message;
2167 *user_msgptr = (addr2.user_message != NULL)?
2168 addr2.user_message : addr2.message;
2169
2170 /* Allow details for temporary error if the address is so flagged. */
2171 if (testflag((&addr2), af_pass_message)) acl_temp_details = TRUE;
2172
2173 /* Make $address_data visible */
2174 deliver_address_data = addr2.prop.address_data;
2175 }
2176
2177 /* We have a result from the relevant test. Handle defer overrides first. */
2178
2179 if (rc == DEFER && (defer_ok ||
2180 (callout_defer_ok && *basic_errno == ERRNO_CALLOUTDEFER)))
2181 {
2182 HDEBUG(D_acl) debug_printf("verify defer overridden by %s\n",
2183 defer_ok? "defer_ok" : "callout_defer_ok");
2184 rc = OK;
2185 }
2186
2187 /* If we've failed a sender, set up a recipient message, and point
2188 sender_verified_failed to the address item that actually failed. */
2189
2190 if (rc != OK && verify_sender_address != NULL)
2191 {
2192 if (rc != DEFER)
2193 *log_msgptr = *user_msgptr = US"Sender verify failed";
2194 else if (*basic_errno != ERRNO_CALLOUTDEFER)
2195 *log_msgptr = *user_msgptr = US"Could not complete sender verify";
2196 else
2197 {
2198 *log_msgptr = US"Could not complete sender verify callout";
2199 *user_msgptr = smtp_return_error_details? sender_vaddr->user_message :
2200 *log_msgptr;
2201 }
2202
2203 sender_verified_failed = sender_vaddr;
2204 }
2205
2206 /* Verifying an address messes up the values of $domain and $local_part,
2207 so reset them before returning if this is a RCPT ACL. */
2208
2209 if (addr != NULL)
2210 {
2211 deliver_domain = addr->domain;
2212 deliver_localpart = addr->local_part;
2213 }
2214 return rc;
2215
2216 /* Syntax errors in the verify argument come here. */
2217
2218 BAD_VERIFY:
2219 *log_msgptr = string_sprintf("expected \"sender[=address]\", \"recipient\", "
2220 "\"helo\", \"header_syntax\", \"header_sender\", \"header_names_ascii\" "
2221 "or \"reverse_host_lookup\" at start of ACL condition "
2222 "\"verify %s\"", arg);
2223 return ERROR;
2224 }
2225
2226
2227
2228
2229 /*************************************************
2230 * Check argument for control= modifier *
2231 *************************************************/
2232
2233 /* Called from acl_check_condition() below
2234
2235 Arguments:
2236 arg the argument string for control=
2237 pptr set to point to the terminating character
2238 where which ACL we are in
2239 log_msgptr for error messages
2240
2241 Returns: CONTROL_xxx value
2242 */
2243
2244 static int
2245 decode_control(const uschar *arg, const uschar **pptr, int where, uschar **log_msgptr)
2246 {
2247 int len;
2248 control_def *d;
2249
2250 for (d = controls_list;
2251 d < controls_list + sizeof(controls_list)/sizeof(control_def);
2252 d++)
2253 {
2254 len = Ustrlen(d->name);
2255 if (Ustrncmp(d->name, arg, len) == 0) break;
2256 }
2257
2258 if (d >= controls_list + sizeof(controls_list)/sizeof(control_def) ||
2259 (arg[len] != 0 && (!d->has_option || arg[len] != '/')))
2260 {
2261 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
2262 return CONTROL_ERROR;
2263 }
2264
2265 *pptr = arg + len;
2266 return d->value;
2267 }
2268
2269
2270
2271
2272 /*************************************************
2273 * Return a ratelimit error *
2274 *************************************************/
2275
2276 /* Called from acl_ratelimit() below
2277
2278 Arguments:
2279 log_msgptr for error messages
2280 format format string
2281 ... supplementary arguments
2282 ss ratelimit option name
2283 where ACL_WHERE_xxxx indicating which ACL this is
2284
2285 Returns: ERROR
2286 */
2287
2288 static int
2289 ratelimit_error(uschar **log_msgptr, const char *format, ...)
2290 {
2291 va_list ap;
2292 uschar buffer[STRING_SPRINTF_BUFFER_SIZE];
2293 va_start(ap, format);
2294 if (!string_vformat(buffer, sizeof(buffer), format, ap))
2295 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
2296 "string_sprintf expansion was longer than " SIZE_T_FMT, sizeof(buffer));
2297 va_end(ap);
2298 *log_msgptr = string_sprintf(
2299 "error in arguments to \"ratelimit\" condition: %s", buffer);
2300 return ERROR;
2301 }
2302
2303
2304
2305
2306 /*************************************************
2307 * Handle rate limiting *
2308 *************************************************/
2309
2310 /* Called by acl_check_condition() below to calculate the result
2311 of the ACL ratelimit condition.
2312
2313 Note that the return value might be slightly unexpected: if the
2314 sender's rate is above the limit then the result is OK. This is
2315 similar to the dnslists condition, and is so that you can write
2316 ACL clauses like: defer ratelimit = 15 / 1h
2317
2318 Arguments:
2319 arg the option string for ratelimit=
2320 where ACL_WHERE_xxxx indicating which ACL this is
2321 log_msgptr for error messages
2322
2323 Returns: OK - Sender's rate is above limit
2324 FAIL - Sender's rate is below limit
2325 DEFER - Problem opening ratelimit database
2326 ERROR - Syntax error in options.
2327 */
2328
2329 static int
2330 acl_ratelimit(const uschar *arg, int where, uschar **log_msgptr)
2331 {
2332 double limit, period, count;
2333 uschar *ss;
2334 uschar *key = NULL;
2335 uschar *unique = NULL;
2336 int sep = '/';
2337 BOOL leaky = FALSE, strict = FALSE, readonly = FALSE;
2338 BOOL noupdate = FALSE, badacl = FALSE;
2339 int mode = RATE_PER_WHAT;
2340 int old_pool, rc;
2341 tree_node **anchor, *t;
2342 open_db dbblock, *dbm;
2343 int dbdb_size;
2344 dbdata_ratelimit *dbd;
2345 dbdata_ratelimit_unique *dbdb;
2346 struct timeval tv;
2347
2348 /* Parse the first two options and record their values in expansion
2349 variables. These variables allow the configuration to have informative
2350 error messages based on rate limits obtained from a table lookup. */
2351
2352 /* First is the maximum number of messages per period / maximum burst
2353 size, which must be greater than or equal to zero. Zero is useful for
2354 rate measurement as opposed to rate limiting. */
2355
2356 sender_rate_limit = string_nextinlist(&arg, &sep, NULL, 0);
2357 if (sender_rate_limit == NULL)
2358 return ratelimit_error(log_msgptr, "sender rate limit not set");
2359
2360 limit = Ustrtod(sender_rate_limit, &ss);
2361 if (tolower(*ss) == 'k') { limit *= 1024.0; ss++; }
2362 else if (tolower(*ss) == 'm') { limit *= 1024.0*1024.0; ss++; }
2363 else if (tolower(*ss) == 'g') { limit *= 1024.0*1024.0*1024.0; ss++; }
2364
2365 if (limit < 0.0 || *ss != '\0')
2366 return ratelimit_error(log_msgptr,
2367 "\"%s\" is not a positive number", sender_rate_limit);
2368
2369 /* Second is the rate measurement period / exponential smoothing time
2370 constant. This must be strictly greater than zero, because zero leads to
2371 run-time division errors. */
2372
2373 sender_rate_period = string_nextinlist(&arg, &sep, NULL, 0);
2374 if (sender_rate_period == NULL) period = -1.0;
2375 else period = readconf_readtime(sender_rate_period, 0, FALSE);
2376 if (period <= 0.0)
2377 return ratelimit_error(log_msgptr,
2378 "\"%s\" is not a time value", sender_rate_period);
2379
2380 /* By default we are counting one of something, but the per_rcpt,
2381 per_byte, and count options can change this. */
2382
2383 count = 1.0;
2384
2385 /* Parse the other options. */
2386
2387 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2388 != NULL)
2389 {
2390 if (strcmpic(ss, US"leaky") == 0) leaky = TRUE;
2391 else if (strcmpic(ss, US"strict") == 0) strict = TRUE;
2392 else if (strcmpic(ss, US"noupdate") == 0) noupdate = TRUE;
2393 else if (strcmpic(ss, US"readonly") == 0) readonly = TRUE;
2394 else if (strcmpic(ss, US"per_cmd") == 0) RATE_SET(mode, PER_CMD);
2395 else if (strcmpic(ss, US"per_conn") == 0)
2396 {
2397 RATE_SET(mode, PER_CONN);
2398 if (where == ACL_WHERE_NOTSMTP || where == ACL_WHERE_NOTSMTP_START)
2399 badacl = TRUE;
2400 }
2401 else if (strcmpic(ss, US"per_mail") == 0)
2402 {
2403 RATE_SET(mode, PER_MAIL);
2404 if (where > ACL_WHERE_NOTSMTP) badacl = TRUE;
2405 }
2406 else if (strcmpic(ss, US"per_rcpt") == 0)
2407 {
2408 /* If we are running in the RCPT ACL, then we'll count the recipients
2409 one by one, but if we are running when we have accumulated the whole
2410 list then we'll add them all in one batch. */
2411 if (where == ACL_WHERE_RCPT)
2412 RATE_SET(mode, PER_RCPT);
2413 else if (where >= ACL_WHERE_PREDATA && where <= ACL_WHERE_NOTSMTP)
2414 RATE_SET(mode, PER_ALLRCPTS), count = (double)recipients_count;
2415 else if (where == ACL_WHERE_MAIL || where > ACL_WHERE_NOTSMTP)
2416 RATE_SET(mode, PER_RCPT), badacl = TRUE;
2417 }
2418 else if (strcmpic(ss, US"per_byte") == 0)
2419 {
2420 /* If we have not yet received the message data and there was no SIZE
2421 declaration on the MAIL comand, then it's safe to just use a value of
2422 zero and let the recorded rate decay as if nothing happened. */
2423 RATE_SET(mode, PER_MAIL);
2424 if (where > ACL_WHERE_NOTSMTP) badacl = TRUE;
2425 else count = message_size < 0 ? 0.0 : (double)message_size;
2426 }
2427 else if (strcmpic(ss, US"per_addr") == 0)
2428 {
2429 RATE_SET(mode, PER_RCPT);
2430 if (where != ACL_WHERE_RCPT) badacl = TRUE, unique = US"*";
2431 else unique = string_sprintf("%s@%s", deliver_localpart, deliver_domain);
2432 }
2433 else if (strncmpic(ss, US"count=", 6) == 0)
2434 {
2435 uschar *e;
2436 count = Ustrtod(ss+6, &e);
2437 if (count < 0.0 || *e != '\0')
2438 return ratelimit_error(log_msgptr,
2439 "\"%s\" is not a positive number", ss);
2440 }
2441 else if (strncmpic(ss, US"unique=", 7) == 0)
2442 unique = string_copy(ss + 7);
2443 else if (key == NULL)
2444 key = string_copy(ss);
2445 else
2446 key = string_sprintf("%s/%s", key, ss);
2447 }
2448
2449 /* Sanity check. When the badacl flag is set the update mode must either
2450 be readonly (which is the default if it is omitted) or, for backwards
2451 compatibility, a combination of noupdate and strict or leaky. */
2452
2453 if (mode == RATE_PER_CLASH)
2454 return ratelimit_error(log_msgptr, "conflicting per_* options");
2455 if (leaky + strict + readonly > 1)
2456 return ratelimit_error(log_msgptr, "conflicting update modes");
2457 if (badacl && (leaky || strict) && !noupdate)
2458 return ratelimit_error(log_msgptr,
2459 "\"%s\" must not have /leaky or /strict option in %s ACL",
2460 ratelimit_option_string[mode], acl_wherenames[where]);
2461
2462 /* Set the default values of any unset options. In readonly mode we
2463 perform the rate computation without any increment so that its value
2464 decays to eventually allow over-limit senders through. */
2465
2466 if (noupdate) readonly = TRUE, leaky = strict = FALSE;
2467 if (badacl) readonly = TRUE;
2468 if (readonly) count = 0.0;
2469 if (!strict && !readonly) leaky = TRUE;
2470 if (mode == RATE_PER_WHAT) mode = RATE_PER_MAIL;
2471
2472 /* Create the lookup key. If there is no explicit key, use sender_host_address.
2473 If there is no sender_host_address (e.g. -bs or acl_not_smtp) then we simply
2474 omit it. The smoothing constant (sender_rate_period) and the per_xxx options
2475 are added to the key because they alter the meaning of the stored data. */
2476
2477 if (key == NULL)
2478 key = (sender_host_address == NULL)? US"" : sender_host_address;
2479
2480 key = string_sprintf("%s/%s/%s%s",
2481 sender_rate_period,
2482 ratelimit_option_string[mode],
2483 unique == NULL ? "" : "unique/",
2484 key);
2485
2486 HDEBUG(D_acl)
2487 debug_printf("ratelimit condition count=%.0f %.1f/%s\n", count, limit, key);
2488
2489 /* See if we have already computed the rate by looking in the relevant tree.
2490 For per-connection rate limiting, store tree nodes and dbdata in the permanent
2491 pool so that they survive across resets. In readonly mode we only remember the
2492 result for the rest of this command in case a later command changes it. After
2493 this bit of logic the code is independent of the per_* mode. */
2494
2495 old_pool = store_pool;
2496
2497 if (readonly)
2498 anchor = &ratelimiters_cmd;
2499 else switch(mode) {
2500 case RATE_PER_CONN:
2501 anchor = &ratelimiters_conn;
2502 store_pool = POOL_PERM;
2503 break;
2504 case RATE_PER_BYTE:
2505 case RATE_PER_MAIL:
2506 case RATE_PER_ALLRCPTS:
2507 anchor = &ratelimiters_mail;
2508 break;
2509 case RATE_PER_ADDR:
2510 case RATE_PER_CMD:
2511 case RATE_PER_RCPT:
2512 anchor = &ratelimiters_cmd;
2513 break;
2514 default:
2515 anchor = NULL; /* silence an "unused" complaint */
2516 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
2517 "internal ACL error: unknown ratelimit mode %d", mode);
2518 break;
2519 }
2520
2521 t = tree_search(*anchor, key);
2522 if (t != NULL)
2523 {
2524 dbd = t->data.ptr;
2525 /* The following few lines duplicate some of the code below. */
2526 rc = (dbd->rate < limit)? FAIL : OK;
2527 store_pool = old_pool;
2528 sender_rate = string_sprintf("%.1f", dbd->rate);
2529 HDEBUG(D_acl)
2530 debug_printf("ratelimit found pre-computed rate %s\n", sender_rate);
2531 return rc;
2532 }
2533
2534 /* We aren't using a pre-computed rate, so get a previously recorded rate
2535 from the database, which will be updated and written back if required. */
2536
2537 dbm = dbfn_open(US"ratelimit", O_RDWR, &dbblock, TRUE);
2538 if (dbm == NULL)
2539 {
2540 store_pool = old_pool;
2541 sender_rate = NULL;
2542 HDEBUG(D_acl) debug_printf("ratelimit database not available\n");
2543 *log_msgptr = US"ratelimit database not available";
2544 return DEFER;
2545 }
2546 dbdb = dbfn_read_with_length(dbm, key, &dbdb_size);
2547 dbd = NULL;
2548
2549 gettimeofday(&tv, NULL);
2550
2551 if (dbdb != NULL)
2552 {
2553 /* Locate the basic ratelimit block inside the DB data. */
2554 HDEBUG(D_acl) debug_printf("ratelimit found key in database\n");
2555 dbd = &dbdb->dbd;
2556
2557 /* Forget the old Bloom filter if it is too old, so that we count each
2558 repeating event once per period. We don't simply clear and re-use the old
2559 filter because we want its size to change if the limit changes. Note that
2560 we keep the dbd pointer for copying the rate into the new data block. */
2561
2562 if(unique != NULL && tv.tv_sec > dbdb->bloom_epoch + period)
2563 {
2564 HDEBUG(D_acl) debug_printf("ratelimit discarding old Bloom filter\n");
2565 dbdb = NULL;
2566 }
2567
2568 /* Sanity check. */
2569
2570 if(unique != NULL && dbdb_size < sizeof(*dbdb))
2571 {
2572 HDEBUG(D_acl) debug_printf("ratelimit discarding undersize Bloom filter\n");
2573 dbdb = NULL;
2574 }
2575 }
2576
2577 /* Allocate a new data block if the database lookup failed
2578 or the Bloom filter passed its age limit. */
2579
2580 if (dbdb == NULL)
2581 {
2582 if (unique == NULL)
2583 {
2584 /* No Bloom filter. This basic ratelimit block is initialized below. */
2585 HDEBUG(D_acl) debug_printf("ratelimit creating new rate data block\n");
2586 dbdb_size = sizeof(*dbd);
2587 dbdb = store_get(dbdb_size);
2588 }
2589 else
2590 {
2591 int extra;
2592 HDEBUG(D_acl) debug_printf("ratelimit creating new Bloom filter\n");
2593
2594 /* See the long comment below for an explanation of the magic number 2.
2595 The filter has a minimum size in case the rate limit is very small;
2596 this is determined by the definition of dbdata_ratelimit_unique. */
2597
2598 extra = (int)limit * 2 - sizeof(dbdb->bloom);
2599 if (extra < 0) extra = 0;
2600 dbdb_size = sizeof(*dbdb) + extra;
2601 dbdb = store_get(dbdb_size);
2602 dbdb->bloom_epoch = tv.tv_sec;
2603 dbdb->bloom_size = sizeof(dbdb->bloom) + extra;
2604 memset(dbdb->bloom, 0, dbdb->bloom_size);
2605
2606 /* Preserve any basic ratelimit data (which is our longer-term memory)
2607 by copying it from the discarded block. */
2608
2609 if (dbd != NULL)
2610 {
2611 dbdb->dbd = *dbd;
2612 dbd = &dbdb->dbd;
2613 }
2614 }
2615 }
2616
2617 /* If we are counting unique events, find out if this event is new or not.
2618 If the client repeats the event during the current period then it should be
2619 counted. We skip this code in readonly mode for efficiency, because any
2620 changes to the filter will be discarded and because count is already set to
2621 zero. */
2622
2623 if (unique != NULL && !readonly)
2624 {
2625 /* We identify unique events using a Bloom filter. (You can find my
2626 notes on Bloom filters at http://fanf.livejournal.com/81696.html)
2627 With the per_addr option, an "event" is a recipient address, though the
2628 user can use the unique option to define their own events. We only count
2629 an event if we have not seen it before.
2630
2631 We size the filter according to the rate limit, which (in leaky mode)
2632 is the limit on the population of the filter. We allow 16 bits of space
2633 per entry (see the construction code above) and we set (up to) 8 of them
2634 when inserting an element (see the loop below). The probability of a false
2635 positive (an event we have not seen before but which we fail to count) is
2636
2637 size = limit * 16
2638 numhash = 8
2639 allzero = exp(-numhash * pop / size)
2640 = exp(-0.5 * pop / limit)
2641 fpr = pow(1 - allzero, numhash)
2642
2643 For senders at the limit the fpr is 0.06% or 1 in 1700
2644 and for senders at half the limit it is 0.0006% or 1 in 170000
2645
2646 In strict mode the Bloom filter can fill up beyond the normal limit, in
2647 which case the false positive rate will rise. This means that the
2648 measured rate for very fast senders can bogusly drop off after a while.
2649
2650 At twice the limit, the fpr is 2.5% or 1 in 40
2651 At four times the limit, it is 31% or 1 in 3.2
2652
2653 It takes ln(pop/limit) periods for an over-limit burst of pop events to
2654 decay below the limit, and if this is more than one then the Bloom filter
2655 will be discarded before the decay gets that far. The false positive rate
2656 at this threshold is 9.3% or 1 in 10.7. */
2657
2658 BOOL seen;
2659 unsigned n, hash, hinc;
2660 uschar md5sum[16];
2661 md5 md5info;
2662
2663 /* Instead of using eight independent hash values, we combine two values
2664 using the formula h1 + n * h2. This does not harm the Bloom filter's
2665 performance, and means the amount of hash we need is independent of the
2666 number of bits we set in the filter. */
2667
2668 md5_start(&md5info);
2669 md5_end(&md5info, unique, Ustrlen(unique), md5sum);
2670 hash = md5sum[0] | md5sum[1] << 8 | md5sum[2] << 16 | md5sum[3] << 24;
2671 hinc = md5sum[4] | md5sum[5] << 8 | md5sum[6] << 16 | md5sum[7] << 24;
2672
2673 /* Scan the bits corresponding to this event. A zero bit means we have
2674 not seen it before. Ensure all bits are set to record this event. */
2675
2676 HDEBUG(D_acl) debug_printf("ratelimit checking uniqueness of %s\n", unique);
2677
2678 seen = TRUE;
2679 for (n = 0; n < 8; n++, hash += hinc)
2680 {
2681 int bit = 1 << (hash % 8);
2682 int byte = (hash / 8) % dbdb->bloom_size;
2683 if ((dbdb->bloom[byte] & bit) == 0)
2684 {
2685 dbdb->bloom[byte] |= bit;
2686 seen = FALSE;
2687 }
2688 }
2689
2690 /* If this event has occurred before, do not count it. */
2691
2692 if (seen)
2693 {
2694 HDEBUG(D_acl) debug_printf("ratelimit event found in Bloom filter\n");
2695 count = 0.0;
2696 }
2697 else
2698 HDEBUG(D_acl) debug_printf("ratelimit event added to Bloom filter\n");
2699 }
2700
2701 /* If there was no previous ratelimit data block for this key, initialize
2702 the new one, otherwise update the block from the database. The initial rate
2703 is what would be computed by the code below for an infinite interval. */
2704
2705 if (dbd == NULL)
2706 {
2707 HDEBUG(D_acl) debug_printf("ratelimit initializing new key's rate data\n");
2708 dbd = &dbdb->dbd;
2709 dbd->time_stamp = tv.tv_sec;
2710 dbd->time_usec = tv.tv_usec;
2711 dbd->rate = count;
2712 }
2713 else
2714 {
2715 /* The smoothed rate is computed using an exponentially weighted moving
2716 average adjusted for variable sampling intervals. The standard EWMA for
2717 a fixed sampling interval is: f'(t) = (1 - a) * f(t) + a * f'(t - 1)
2718 where f() is the measured value and f'() is the smoothed value.
2719
2720 Old data decays out of the smoothed value exponentially, such that data n
2721 samples old is multiplied by a^n. The exponential decay time constant p
2722 is defined such that data p samples old is multiplied by 1/e, which means
2723 that a = exp(-1/p). We can maintain the same time constant for a variable
2724 sampling interval i by using a = exp(-i/p).
2725
2726 The rate we are measuring is messages per period, suitable for directly
2727 comparing with the limit. The average rate between now and the previous
2728 message is period / interval, which we feed into the EWMA as the sample.
2729
2730 It turns out that the number of messages required for the smoothed rate
2731 to reach the limit when they are sent in a burst is equal to the limit.
2732 This can be seen by analysing the value of the smoothed rate after N
2733 messages sent at even intervals. Let k = (1 - a) * p/i
2734
2735 rate_1 = (1 - a) * p/i + a * rate_0
2736 = k + a * rate_0
2737 rate_2 = k + a * rate_1
2738 = k + a * k + a^2 * rate_0
2739 rate_3 = k + a * k + a^2 * k + a^3 * rate_0
2740 rate_N = rate_0 * a^N + k * SUM(x=0..N-1)(a^x)
2741 = rate_0 * a^N + k * (1 - a^N) / (1 - a)
2742 = rate_0 * a^N + p/i * (1 - a^N)
2743
2744 When N is large, a^N -> 0 so rate_N -> p/i as desired.
2745
2746 rate_N = p/i + (rate_0 - p/i) * a^N
2747 a^N = (rate_N - p/i) / (rate_0 - p/i)
2748 N * -i/p = log((rate_N - p/i) / (rate_0 - p/i))
2749 N = p/i * log((rate_0 - p/i) / (rate_N - p/i))
2750
2751 Numerical analysis of the above equation, setting the computed rate to
2752 increase from rate_0 = 0 to rate_N = limit, shows that for large sending
2753 rates, p/i, the number of messages N = limit. So limit serves as both the
2754 maximum rate measured in messages per period, and the maximum number of
2755 messages that can be sent in a fast burst. */
2756
2757 double this_time = (double)tv.tv_sec
2758 + (double)tv.tv_usec / 1000000.0;
2759 double prev_time = (double)dbd->time_stamp
2760 + (double)dbd->time_usec / 1000000.0;
2761
2762 /* We must avoid division by zero, and deal gracefully with the clock going
2763 backwards. If we blunder ahead when time is in reverse then the computed
2764 rate will be bogus. To be safe we clamp interval to a very small number. */
2765
2766 double interval = this_time - prev_time <= 0.0 ? 1e-9
2767 : this_time - prev_time;
2768
2769 double i_over_p = interval / period;
2770 double a = exp(-i_over_p);
2771
2772 /* Combine the instantaneous rate (period / interval) with the previous rate
2773 using the smoothing factor a. In order to measure sized events, multiply the
2774 instantaneous rate by the count of bytes or recipients etc. */
2775
2776 dbd->time_stamp = tv.tv_sec;
2777 dbd->time_usec = tv.tv_usec;
2778 dbd->rate = (1 - a) * count / i_over_p + a * dbd->rate;
2779
2780 /* When events are very widely spaced the computed rate tends towards zero.
2781 Although this is accurate it turns out not to be useful for our purposes,
2782 especially when the first event after a long silence is the start of a spam
2783 run. A more useful model is that the rate for an isolated event should be the
2784 size of the event per the period size, ignoring the lack of events outside
2785 the current period and regardless of where the event falls in the period. So,
2786 if the interval was so long that the calculated rate is unhelpfully small, we
2787 re-intialize the rate. In the absence of higher-rate bursts, the condition
2788 below is true if the interval is greater than the period. */
2789
2790 if (dbd->rate < count) dbd->rate = count;
2791 }
2792
2793 /* Clients sending at the limit are considered to be over the limit.
2794 This matters for edge cases such as a limit of zero, when the client
2795 should be completely blocked. */
2796
2797 rc = (dbd->rate < limit)? FAIL : OK;
2798
2799 /* Update the state if the rate is low or if we are being strict. If we
2800 are in leaky mode and the sender's rate is too high, we do not update
2801 the recorded rate in order to avoid an over-aggressive sender's retry
2802 rate preventing them from getting any email through. If readonly is set,
2803 neither leaky nor strict are set, so we do not do any updates. */
2804
2805 if ((rc == FAIL && leaky) || strict)
2806 {
2807 dbfn_write(dbm, key, dbdb, dbdb_size);
2808 HDEBUG(D_acl) debug_printf("ratelimit db updated\n");
2809 }
2810 else
2811 {
2812 HDEBUG(D_acl) debug_printf("ratelimit db not updated: %s\n",
2813 readonly? "readonly mode" : "over the limit, but leaky");
2814 }
2815
2816 dbfn_close(dbm);
2817
2818 /* Store the result in the tree for future reference. */
2819
2820 t = store_get(sizeof(tree_node) + Ustrlen(key));
2821 t->data.ptr = dbd;
2822 Ustrcpy(t->name, key);
2823 (void)tree_insertnode(anchor, t);
2824
2825 /* We create the formatted version of the sender's rate very late in
2826 order to ensure that it is done using the correct storage pool. */
2827
2828 store_pool = old_pool;
2829 sender_rate = string_sprintf("%.1f", dbd->rate);
2830
2831 HDEBUG(D_acl)
2832 debug_printf("ratelimit computed rate %s\n", sender_rate);
2833
2834 return rc;
2835 }
2836
2837
2838
2839 /*************************************************
2840 * The udpsend ACL modifier *
2841 *************************************************/
2842
2843 /* Called by acl_check_condition() below.
2844
2845 Arguments:
2846 arg the option string for udpsend=
2847 log_msgptr for error messages
2848
2849 Returns: OK - Completed.
2850 DEFER - Problem with DNS lookup.
2851 ERROR - Syntax error in options.
2852 */
2853
2854 static int
2855 acl_udpsend(const uschar *arg, uschar **log_msgptr)
2856 {
2857 int sep = 0;
2858 uschar *hostname;
2859 uschar *portstr;
2860 uschar *portend;
2861 host_item *h;
2862 int portnum;
2863 int len;
2864 int r, s;
2865 uschar * errstr;
2866
2867 hostname = string_nextinlist(&arg, &sep, NULL, 0);
2868 portstr = string_nextinlist(&arg, &sep, NULL, 0);
2869
2870 if (hostname == NULL)
2871 {
2872 *log_msgptr = US"missing destination host in \"udpsend\" modifier";
2873 return ERROR;
2874 }
2875 if (portstr == NULL)
2876 {
2877 *log_msgptr = US"missing destination port in \"udpsend\" modifier";
2878 return ERROR;
2879 }
2880 if (arg == NULL)
2881 {
2882 *log_msgptr = US"missing datagram payload in \"udpsend\" modifier";
2883 return ERROR;
2884 }
2885 portnum = Ustrtol(portstr, &portend, 10);
2886 if (*portend != '\0')
2887 {
2888 *log_msgptr = US"bad destination port in \"udpsend\" modifier";
2889 return ERROR;
2890 }
2891
2892 /* Make a single-item host list. */
2893 h = store_get(sizeof(host_item));
2894 memset(h, 0, sizeof(host_item));
2895 h->name = hostname;
2896 h->port = portnum;
2897 h->mx = MX_NONE;
2898
2899 if (string_is_ip_address(hostname, NULL))
2900 h->address = hostname, r = HOST_FOUND;
2901 else
2902 r = host_find_byname(h, NULL, 0, NULL, FALSE);
2903 if (r == HOST_FIND_FAILED || r == HOST_FIND_AGAIN)
2904 {
2905 *log_msgptr = US"DNS lookup failed in \"udpsend\" modifier";
2906 return DEFER;
2907 }
2908
2909 HDEBUG(D_acl)
2910 debug_printf("udpsend [%s]:%d %s\n", h->address, portnum, arg);
2911
2912 r = s = ip_connectedsocket(SOCK_DGRAM, h->address, portnum, portnum,
2913 1, NULL, &errstr);
2914 if (r < 0) goto defer;
2915 len = Ustrlen(arg);
2916 r = send(s, arg, len, 0);
2917 if (r < 0)
2918 {
2919 errstr = US strerror(errno);
2920 close(s);
2921 goto defer;
2922 }
2923 close(s);
2924 if (r < len)
2925 {
2926 *log_msgptr =
2927 string_sprintf("\"udpsend\" truncated from %d to %d octets", len, r);
2928 return DEFER;
2929 }
2930
2931 HDEBUG(D_acl)
2932 debug_printf("udpsend %d bytes\n", r);
2933
2934 return OK;
2935
2936 defer:
2937 *log_msgptr = string_sprintf("\"udpsend\" failed: %s", errstr);
2938 return DEFER;
2939 }
2940
2941
2942
2943 /*************************************************
2944 * Handle conditions/modifiers on an ACL item *
2945 *************************************************/
2946
2947 /* Called from acl_check() below.
2948
2949 Arguments:
2950 verb ACL verb
2951 cb ACL condition block - if NULL, result is OK
2952 where where called from
2953 addr the address being checked for RCPT, or NULL
2954 level the nesting level
2955 epp pointer to pass back TRUE if "endpass" encountered
2956 (applies only to "accept" and "discard")
2957 user_msgptr user message pointer
2958 log_msgptr log message pointer
2959 basic_errno pointer to where to put verify error
2960
2961 Returns: OK - all conditions are met
2962 DISCARD - an "acl" condition returned DISCARD - only allowed
2963 for "accept" or "discard" verbs
2964 FAIL - at least one condition fails
2965 FAIL_DROP - an "acl" condition returned FAIL_DROP
2966 DEFER - can't tell at the moment (typically, lookup defer,
2967 but can be temporary callout problem)
2968 ERROR - ERROR from nested ACL or expansion failure or other
2969 error
2970 */
2971
2972 static int
2973 acl_check_condition(int verb, acl_condition_block *cb, int where,
2974 address_item *addr, int level, BOOL *epp, uschar **user_msgptr,
2975 uschar **log_msgptr, int *basic_errno)
2976 {
2977 uschar *user_message = NULL;
2978 uschar *log_message = NULL;
2979 uschar *debug_tag = NULL;
2980 uschar *debug_opts = NULL;
2981 int rc = OK;
2982 #ifdef WITH_CONTENT_SCAN
2983 int sep = -'/';
2984 #endif
2985
2986 for (; cb != NULL; cb = cb->next)
2987 {
2988 const uschar *arg;
2989 int control_type;
2990
2991 /* The message and log_message items set up messages to be used in
2992 case of rejection. They are expanded later. */
2993
2994 if (cb->type == ACLC_MESSAGE)
2995 {
2996 HDEBUG(D_acl) debug_printf(" message: %s\n", cb->arg);
2997 user_message = cb->arg;
2998 continue;
2999 }
3000
3001 if (cb->type == ACLC_LOG_MESSAGE)
3002 {
3003 HDEBUG(D_acl) debug_printf("l_message: %s\n", cb->arg);
3004 log_message = cb->arg;
3005 continue;
3006 }
3007
3008 /* The endpass "condition" just sets a flag to show it occurred. This is
3009 checked at compile time to be on an "accept" or "discard" item. */
3010
3011 if (cb->type == ACLC_ENDPASS)
3012 {
3013 *epp = TRUE;
3014 continue;
3015 }
3016
3017 /* For other conditions and modifiers, the argument is expanded now for some
3018 of them, but not for all, because expansion happens down in some lower level
3019 checking functions in some cases. */
3020
3021 if (cond_expand_at_top[cb->type])
3022 {
3023 arg = expand_string(cb->arg);
3024 if (arg == NULL)
3025 {
3026 if (expand_string_forcedfail) continue;
3027 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s",
3028 cb->arg, expand_string_message);
3029 return search_find_defer? DEFER : ERROR;
3030 }
3031 }
3032 else arg = cb->arg;
3033
3034 /* Show condition, and expanded condition if it's different */
3035
3036 HDEBUG(D_acl)
3037 {
3038 int lhswidth = 0;
3039 debug_printf("check %s%s %n",
3040 (!cond_modifiers[cb->type] && cb->u.negated)? "!":"",
3041 conditions[cb->type], &lhswidth);
3042
3043 if (cb->type == ACLC_SET)
3044 {
3045 debug_printf("acl_%s ", cb->u.varname);
3046 lhswidth += 5 + Ustrlen(cb->u.varname);
3047 }
3048
3049 debug_printf("= %s\n", cb->arg);
3050
3051 if (arg != cb->arg)
3052 debug_printf("%.*s= %s\n", lhswidth,
3053 US" ", CS arg);
3054 }
3055
3056 /* Check that this condition makes sense at this time */
3057
3058 if ((cond_forbids[cb->type] & (1 << where)) != 0)
3059 {
3060 *log_msgptr = string_sprintf("cannot %s %s condition in %s ACL",
3061 cond_modifiers[cb->type]? "use" : "test",
3062 conditions[cb->type], acl_wherenames[where]);
3063 return ERROR;
3064 }
3065
3066 /* Run the appropriate test for each condition, or take the appropriate
3067 action for the remaining modifiers. */
3068
3069 switch(cb->type)
3070 {
3071 case ACLC_ADD_HEADER:
3072 setup_header(arg);
3073 break;
3074
3075 /* A nested ACL that returns "discard" makes sense only for an "accept" or
3076 "discard" verb. */
3077
3078 case ACLC_ACL:
3079 rc = acl_check_wargs(where, addr, arg, level+1, user_msgptr, log_msgptr);
3080 if (rc == DISCARD && verb != ACL_ACCEPT && verb != ACL_DISCARD)
3081 {
3082 *log_msgptr = string_sprintf("nested ACL returned \"discard\" for "
3083 "\"%s\" command (only allowed with \"accept\" or \"discard\")",
3084 verbs[verb]);
3085 return ERROR;
3086 }
3087 break;
3088
3089 case ACLC_AUTHENTICATED:
3090 rc = (sender_host_authenticated == NULL)? FAIL :
3091 match_isinlist(sender_host_authenticated, &arg, 0, NULL, NULL, MCL_STRING,
3092 TRUE, NULL);
3093 break;
3094
3095 #ifdef EXPERIMENTAL_BRIGHTMAIL
3096 case ACLC_BMI_OPTIN:
3097 {
3098 int old_pool = store_pool;
3099 store_pool = POOL_PERM;
3100 bmi_current_optin = string_copy(arg);
3101 store_pool = old_pool;
3102 }
3103 break;
3104 #endif
3105
3106 case ACLC_CONDITION:
3107 /* The true/false parsing here should be kept in sync with that used in
3108 expand.c when dealing with ECOND_BOOL so that we don't have too many
3109 different definitions of what can be a boolean. */
3110 if (*arg == '-'
3111 ? Ustrspn(arg+1, "0123456789") == Ustrlen(arg+1) /* Negative number */
3112 : Ustrspn(arg, "0123456789") == Ustrlen(arg)) /* Digits, or empty */
3113 rc = (Uatoi(arg) == 0)? FAIL : OK;
3114 else
3115 rc = (strcmpic(arg, US"no") == 0 ||
3116 strcmpic(arg, US"false") == 0)? FAIL :
3117 (strcmpic(arg, US"yes") == 0 ||
3118 strcmpic(arg, US"true") == 0)? OK : DEFER;
3119 if (rc == DEFER)
3120 *log_msgptr = string_sprintf("invalid \"condition\" value \"%s\"", arg);
3121 break;
3122
3123 case ACLC_CONTINUE: /* Always succeeds */
3124 break;
3125
3126 case ACLC_CONTROL:
3127 {
3128 const uschar *p = NULL;
3129 control_type = decode_control(arg, &p, where, log_msgptr);
3130
3131 /* Check if this control makes sense at this time */
3132
3133 if ((control_forbids[control_type] & (1 << where)) != 0)
3134 {
3135 *log_msgptr = string_sprintf("cannot use \"control=%s\" in %s ACL",
3136 controls[control_type], acl_wherenames[where]);
3137 return ERROR;
3138 }
3139
3140 switch(control_type)
3141 {
3142 case CONTROL_AUTH_UNADVERTISED:
3143 allow_auth_unadvertised = TRUE;
3144 break;
3145
3146 #ifdef EXPERIMENTAL_BRIGHTMAIL
3147 case CONTROL_BMI_RUN:
3148 bmi_run = 1;
3149 break;
3150 #endif
3151
3152 #ifndef DISABLE_DKIM
3153 case CONTROL_DKIM_VERIFY:
3154 dkim_disable_verify = TRUE;
3155 #ifdef EXPERIMENTAL_DMARC
3156 /* Since DKIM was blocked, skip DMARC too */
3157 dmarc_disable_verify = TRUE;
3158 dmarc_enable_forensic = FALSE;
3159 #endif
3160 break;
3161 #endif
3162
3163 #ifdef EXPERIMENTAL_DMARC
3164 case CONTROL_DMARC_VERIFY:
3165 dmarc_disable_verify = TRUE;
3166 break;
3167
3168 case CONTROL_DMARC_FORENSIC:
3169 dmarc_enable_forensic = TRUE;
3170 break;
3171 #endif
3172
3173 case CONTROL_DSCP:
3174 if (*p == '/')
3175 {
3176 int fd, af, level, optname, value;
3177 /* If we are acting on stdin, the setsockopt may fail if stdin is not
3178 a socket; we can accept that, we'll just debug-log failures anyway. */
3179 fd = fileno(smtp_in);
3180 af = ip_get_address_family(fd);
3181 if (af < 0)
3182 {
3183 HDEBUG(D_acl)
3184 debug_printf("smtp input is probably not a socket [%s], not setting DSCP\n",
3185 strerror(errno));
3186 break;
3187 }
3188 if (dscp_lookup(p+1, af, &level, &optname, &value))
3189 {
3190 if (setsockopt(fd, level, optname, &value, sizeof(value)) < 0)
3191 {
3192 HDEBUG(D_acl) debug_printf("failed to set input DSCP[%s]: %s\n",
3193 p+1, strerror(errno));
3194 }
3195 else
3196 {
3197 HDEBUG(D_acl) debug_printf("set input DSCP to \"%s\"\n", p+1);
3198 }
3199 }
3200 else
3201 {
3202 *log_msgptr = string_sprintf("unrecognised DSCP value in \"control=%s\"", arg);
3203 return ERROR;
3204 }
3205 }
3206 else
3207 {
3208 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3209 return ERROR;
3210 }
3211 break;
3212
3213 case CONTROL_ERROR:
3214 return ERROR;
3215
3216 case CONTROL_CASEFUL_LOCAL_PART:
3217 deliver_localpart = addr->cc_local_part;
3218 break;
3219
3220 case CONTROL_CASELOWER_LOCAL_PART:
3221 deliver_localpart = addr->lc_local_part;
3222 break;
3223
3224 case CONTROL_ENFORCE_SYNC:
3225 smtp_enforce_sync = TRUE;
3226 break;
3227
3228 case CONTROL_NO_ENFORCE_SYNC:
3229 smtp_enforce_sync = FALSE;
3230 break;
3231
3232 #ifdef WITH_CONTENT_SCAN
3233 case CONTROL_NO_MBOX_UNSPOOL:
3234 no_mbox_unspool = TRUE;
3235 break;
3236 #endif
3237
3238 case CONTROL_NO_MULTILINE:
3239 no_multiline_responses = TRUE;
3240 break;
3241
3242 case CONTROL_NO_PIPELINING:
3243 pipelining_enable = FALSE;
3244 break;
3245
3246 case CONTROL_NO_DELAY_FLUSH:
3247 disable_delay_flush = TRUE;
3248 break;
3249
3250 case CONTROL_NO_CALLOUT_FLUSH:
3251 disable_callout_flush = TRUE;
3252 break;
3253
3254 case CONTROL_FAKEREJECT:
3255 cancel_cutthrough_connection("fakereject");
3256 case CONTROL_FAKEDEFER:
3257 fake_response = (control_type == CONTROL_FAKEDEFER) ? DEFER : FAIL;
3258 if (*p == '/')
3259 {
3260 const uschar *pp = p + 1;
3261 while (*pp != 0) pp++;
3262 fake_response_text = expand_string(string_copyn(p+1, pp-p-1));
3263 p = pp;
3264 }
3265 else
3266 {
3267 /* Explicitly reset to default string */
3268 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).";
3269 }
3270 break;
3271
3272 case CONTROL_FREEZE:
3273 deliver_freeze = TRUE;
3274 deliver_frozen_at = time(NULL);
3275 freeze_tell = freeze_tell_config; /* Reset to configured value */
3276 if (Ustrncmp(p, "/no_tell", 8) == 0)
3277 {
3278 p += 8;
3279 freeze_tell = NULL;
3280 }
3281 if (*p != 0)
3282 {
3283 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3284 return ERROR;
3285 }
3286 cancel_cutthrough_connection("item frozen");
3287 break;
3288
3289 case CONTROL_QUEUE_ONLY:
3290 queue_only_policy = TRUE;
3291 cancel_cutthrough_connection("queueing forced");
3292 break;
3293
3294 case CONTROL_SUBMISSION:
3295 originator_name = US"";
3296 submission_mode = TRUE;
3297 while (*p == '/')
3298 {
3299 if (Ustrncmp(p, "/sender_retain", 14) == 0)
3300 {
3301 p += 14;
3302 active_local_sender_retain = TRUE;
3303 active_local_from_check = FALSE;
3304 }
3305 else if (Ustrncmp(p, "/domain=", 8) == 0)
3306 {
3307 const uschar *pp = p + 8;
3308 while (*pp != 0 && *pp != '/') pp++;
3309 submission_domain = string_copyn(p+8, pp-p-8);
3310 p = pp;
3311 }
3312 /* The name= option must be last, because it swallows the rest of
3313 the string. */
3314 else if (Ustrncmp(p, "/name=", 6) == 0)
3315 {
3316 const uschar *pp = p + 6;
3317 while (*pp != 0) pp++;
3318 submission_name = string_copy(parse_fix_phrase(p+6, pp-p-6,
3319 big_buffer, big_buffer_size));
3320 p = pp;
3321 }
3322 else break;
3323 }
3324 if (*p != 0)
3325 {
3326 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3327 return ERROR;
3328 }
3329 break;
3330
3331 case CONTROL_DEBUG:
3332 while (*p == '/')
3333 {
3334 if (Ustrncmp(p, "/tag=", 5) == 0)
3335 {
3336 const uschar *pp = p + 5;
3337 while (*pp != '\0' && *pp != '/') pp++;
3338 debug_tag = string_copyn(p+5, pp-p-5);
3339 p = pp;
3340 }
3341 else if (Ustrncmp(p, "/opts=", 6) == 0)
3342 {
3343 const uschar *pp = p + 6;
3344 while (*pp != '\0' && *pp != '/') pp++;
3345 debug_opts = string_copyn(p+6, pp-p-6);
3346 p = pp;
3347 }
3348 }
3349 debug_logging_activate(debug_tag, debug_opts);
3350 break;
3351
3352 case CONTROL_SUPPRESS_LOCAL_FIXUPS:
3353 suppress_local_fixups = TRUE;
3354 break;
3355
3356 case CONTROL_CUTTHROUGH_DELIVERY:
3357 #ifndef DISABLE_PRDR
3358 if (prdr_requested)
3359 #else
3360 if (0)
3361 #endif
3362 /* Too hard to think about for now. We might in future cutthrough
3363 the case where both sides handle prdr and this-node prdr acl
3364 is "accept" */
3365 *log_msgptr = string_sprintf("PRDR on %s reception\n", arg);
3366 else
3367 {
3368 if (deliver_freeze)
3369 *log_msgptr = US"frozen";
3370 else if (queue_only_policy)
3371 *log_msgptr = US"queue-only";
3372 else if (fake_response == FAIL)
3373 *log_msgptr = US"fakereject";
3374 else
3375 {
3376 if (rcpt_count == 1) cutthrough.delivery = TRUE;
3377 break;
3378 }
3379 *log_msgptr = string_sprintf("\"control=%s\" on %s item",
3380 arg, *log_msgptr);
3381 }
3382 return ERROR;
3383
3384 #ifdef SUPPORT_I18N
3385 case CONTROL_UTF8_DOWNCONVERT:
3386 if (*p == '/')
3387 {
3388 if (p[1] == '1')
3389 {
3390 message_utf8_downconvert = 1;
3391 addr->prop.utf8_downcvt = TRUE;
3392 addr->prop.utf8_downcvt_maybe = FALSE;
3393 p += 2;
3394 break;
3395 }
3396 if (p[1] == '0')
3397 {
3398 message_utf8_downconvert = 0;
3399 addr->prop.utf8_downcvt = FALSE;
3400 addr->prop.utf8_downcvt_maybe = FALSE;
3401 p += 2;
3402 break;
3403 }
3404 if (p[1] == '-' && p[2] == '1')
3405 {
3406 message_utf8_downconvert = -1;
3407 addr->prop.utf8_downcvt = FALSE;
3408 addr->prop.utf8_downcvt_maybe = TRUE;
3409 p += 3;
3410 break;
3411 }
3412 *log_msgptr = US"bad option value for control=utf8_downconvert";
3413 }
3414 else
3415 {
3416 message_utf8_downconvert = 1;
3417 addr->prop.utf8_downcvt = TRUE;
3418 addr->prop.utf8_downcvt_maybe = FALSE;
3419 break;
3420 }
3421 return ERROR;
3422 #endif
3423
3424 }
3425 break;
3426 }
3427
3428 #ifdef EXPERIMENTAL_DCC
3429 case ACLC_DCC:
3430 {
3431 /* Seperate the regular expression and any optional parameters. */
3432 const uschar * list = arg;
3433 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
3434 /* Run the dcc backend. */
3435 rc = dcc_process(&ss);
3436 /* Modify return code based upon the existance of options. */
3437 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size)))
3438 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
3439 rc = FAIL; /* FAIL so that the message is passed to the next ACL */
3440 }
3441 break;
3442 #endif
3443
3444 #ifdef WITH_CONTENT_SCAN
3445 case ACLC_DECODE:
3446 rc = mime_decode(&arg);
3447 break;
3448 #endif
3449
3450 case ACLC_DELAY:
3451 {
3452 int delay = readconf_readtime(arg, 0, FALSE);
3453 if (delay < 0)
3454 {
3455 *log_msgptr = string_sprintf("syntax error in argument for \"delay\" "
3456 "modifier: \"%s\" is not a time value", arg);
3457 return ERROR;
3458 }
3459 else
3460 {
3461 HDEBUG(D_acl) debug_printf("delay modifier requests %d-second delay\n",
3462 delay);
3463 if (host_checking)
3464 {
3465 HDEBUG(D_acl)
3466 debug_printf("delay skipped in -bh checking mode\n");
3467 }
3468
3469 /* NOTE 1: Remember that we may be
3470 dealing with stdin/stdout here, in addition to TCP/IP connections.
3471 Also, delays may be specified for non-SMTP input, where smtp_out and
3472 smtp_in will be NULL. Whatever is done must work in all cases.
3473
3474 NOTE 2: The added feature of flushing the output before a delay must
3475 apply only to SMTP input. Hence the test for smtp_out being non-NULL.
3476 */
3477
3478 else
3479 {