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