1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2013 */
6 /* See the file NOTICE for conditions of use and distribution. */
8 /* Code for handling Access Control Lists (ACLs) */
13 /* Default callout timeout */
15 #define CALLOUT_TIMEOUT_DEFAULT 30
17 /* ACL verb codes - keep in step with the table of verbs that follows */
19 enum { ACL_ACCEPT, ACL_DEFER, ACL_DENY, ACL_DISCARD, ACL_DROP, ACL_REQUIRE,
24 static uschar *verbs[] = {
33 /* For each verb, the conditions for which "message" or "log_message" are used
34 are held as a bitmap. This is to avoid expanding the strings unnecessarily. For
35 "accept", the FAIL case is used only after "endpass", but that is selected in
38 static int msgcond[] = {
39 (1<<OK) | (1<<FAIL) | (1<<FAIL_DROP), /* accept */
42 (1<<OK) | (1<<FAIL) | (1<<FAIL_DROP), /* discard */
44 (1<<FAIL) | (1<<FAIL_DROP), /* require */
48 /* ACL condition and modifier codes - keep in step with the table that
49 follows, and the cond_expand_at_top and uschar cond_modifiers tables lower
55 #ifdef EXPERIMENTAL_BRIGHTMAIL
61 #ifdef EXPERIMENTAL_DCC
64 #ifdef WITH_CONTENT_SCAN
68 #ifdef WITH_OLD_DEMIME
75 #ifdef EXPERIMENTAL_DMARC
85 ACLC_LOG_REJECT_TARGET,
87 #ifdef WITH_CONTENT_SCAN
91 #ifdef WITH_CONTENT_SCAN
96 #ifdef WITH_CONTENT_SCAN
103 #ifdef WITH_CONTENT_SCAN
106 #ifdef EXPERIMENTAL_SPF
113 /* ACL conditions/modifiers: "delay", "control", "continue", "endpass",
114 "message", "log_message", "log_reject_target", "logwrite", and "set" are
115 modifiers that look like conditions but always return TRUE. They are used for
116 their side effects. */
118 static uschar *conditions[] = {
122 #ifdef EXPERIMENTAL_BRIGHTMAIL
128 #ifdef EXPERIMENTAL_DCC
131 #ifdef WITH_CONTENT_SCAN
135 #ifdef WITH_OLD_DEMIME
142 #ifdef EXPERIMENTAL_DMARC
152 US"log_reject_target",
154 #ifdef WITH_CONTENT_SCAN
158 #ifdef WITH_CONTENT_SCAN
163 #ifdef WITH_CONTENT_SCAN
167 US"sender_domains", US"senders", US"set",
168 #ifdef WITH_CONTENT_SCAN
171 #ifdef EXPERIMENTAL_SPF
179 /* Return values from decode_control(); keep in step with the table of names
183 CONTROL_AUTH_UNADVERTISED,
184 #ifdef EXPERIMENTAL_BRIGHTMAIL
191 #ifdef EXPERIMENTAL_DMARC
192 CONTROL_DMARC_VERIFY,
193 CONTROL_DMARC_FORENSIC,
197 CONTROL_CASEFUL_LOCAL_PART,
198 CONTROL_CASELOWER_LOCAL_PART,
199 CONTROL_CUTTHROUGH_DELIVERY,
200 CONTROL_ENFORCE_SYNC,
201 CONTROL_NO_ENFORCE_SYNC,
205 CONTROL_SUPPRESS_LOCAL_FIXUPS,
206 #ifdef WITH_CONTENT_SCAN
207 CONTROL_NO_MBOX_UNSPOOL,
211 CONTROL_NO_MULTILINE,
212 CONTROL_NO_PIPELINING,
213 CONTROL_NO_DELAY_FLUSH,
214 CONTROL_NO_CALLOUT_FLUSH
217 /* ACL control names; keep in step with the table above! This list is used for
218 turning ids into names. The actual list of recognized names is in the variable
219 control_def controls_list[] below. The fact that there are two lists is a mess
220 and should be tidied up. */
222 static uschar *controls[] = {
223 US"allow_auth_unadvertised",
224 #ifdef EXPERIMENTAL_BRIGHTMAIL
229 US"dkim_disable_verify",
231 #ifdef EXPERIMENTAL_DMARC
232 US"dmarc_disable_verify",
233 US"dmarc_enable_forensic",
237 US"caseful_local_part",
238 US"caselower_local_part",
239 US"cutthrough_delivery",
245 US"suppress_local_fixups",
246 #ifdef WITH_CONTENT_SCAN
251 US"no_multiline_responses",
257 /* Flags to indicate for which conditions/modifiers a string expansion is done
258 at the outer level. In the other cases, expansion already occurs in the
259 checking functions. */
261 static uschar cond_expand_at_top[] = {
263 TRUE, /* add_header */
264 FALSE, /* authenticated */
265 #ifdef EXPERIMENTAL_BRIGHTMAIL
266 TRUE, /* bmi_optin */
268 TRUE, /* condition */
271 #ifdef EXPERIMENTAL_DCC
274 #ifdef WITH_CONTENT_SCAN
278 #ifdef WITH_OLD_DEMIME
282 TRUE, /* dkim_signers */
283 TRUE, /* dkim_status */
285 #ifdef EXPERIMENTAL_DMARC
286 TRUE, /* dmarc_status */
290 FALSE, /* encrypted */
293 FALSE, /* local_parts */
294 TRUE, /* log_message */
295 TRUE, /* log_reject_target */
297 #ifdef WITH_CONTENT_SCAN
301 #ifdef WITH_CONTENT_SCAN
302 TRUE, /* mime_regex */
304 TRUE, /* ratelimit */
305 FALSE, /* recipients */
306 #ifdef WITH_CONTENT_SCAN
309 TRUE, /* remove_header */
310 FALSE, /* sender_domains */
313 #ifdef WITH_CONTENT_SCAN
316 #ifdef EXPERIMENTAL_SPF
318 TRUE, /* spf_guess */
324 /* Flags to identify the modifiers */
326 static uschar cond_modifiers[] = {
328 TRUE, /* add_header */
329 FALSE, /* authenticated */
330 #ifdef EXPERIMENTAL_BRIGHTMAIL
331 TRUE, /* bmi_optin */
333 FALSE, /* condition */
336 #ifdef EXPERIMENTAL_DCC
339 #ifdef WITH_CONTENT_SCAN
343 #ifdef WITH_OLD_DEMIME
347 FALSE, /* dkim_signers */
348 FALSE, /* dkim_status */
350 #ifdef EXPERIMENTAL_DMARC
351 FALSE, /* dmarc_status */
353 FALSE, /* dnslists */
355 FALSE, /* encrypted */
358 FALSE, /* local_parts */
359 TRUE, /* log_message */
360 TRUE, /* log_reject_target */
362 #ifdef WITH_CONTENT_SCAN
366 #ifdef WITH_CONTENT_SCAN
367 FALSE, /* mime_regex */
369 FALSE, /* ratelimit */
370 FALSE, /* recipients */
371 #ifdef WITH_CONTENT_SCAN
374 TRUE, /* remove_header */
375 FALSE, /* sender_domains */
378 #ifdef WITH_CONTENT_SCAN
381 #ifdef EXPERIMENTAL_SPF
383 FALSE, /* spf_guess */
389 /* Bit map vector of which conditions and modifiers are not allowed at certain
390 times. For each condition and modifier, there's a bitmap of dis-allowed times.
391 For some, it is easier to specify the negation of a small number of allowed
394 static unsigned int cond_forbids[] = {
398 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* add_header */
399 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
400 #ifdef EXPERIMENTAL_PRDR
403 (1<<ACL_WHERE_MIME)|(1<<ACL_WHERE_NOTSMTP)|
405 (1<<ACL_WHERE_NOTSMTP_START)),
407 (1<<ACL_WHERE_NOTSMTP)| /* authenticated */
408 (1<<ACL_WHERE_NOTSMTP_START)|
409 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO),
411 #ifdef EXPERIMENTAL_BRIGHTMAIL
412 (1<<ACL_WHERE_AUTH)| /* bmi_optin */
413 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
414 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_MIME)|
415 #ifdef EXPERIMENTAL_PRDR
418 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
419 (1<<ACL_WHERE_MAILAUTH)|
420 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
421 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_PREDATA)|
422 (1<<ACL_WHERE_NOTSMTP_START),
429 /* Certain types of control are always allowed, so we let it through
430 always and check in the control processing itself. */
434 #ifdef EXPERIMENTAL_DCC
436 ~((1<<ACL_WHERE_DATA)| /* dcc */
437 #ifdef EXPERIMENTAL_PRDR
439 #endif /* EXPERIMENTAL_PRDR */
440 (1<<ACL_WHERE_NOTSMTP)),
443 #ifdef WITH_CONTENT_SCAN
445 ~(1<<ACL_WHERE_MIME), /* decode */
448 (1<<ACL_WHERE_NOTQUIT), /* delay */
450 #ifdef WITH_OLD_DEMIME
452 ~((1<<ACL_WHERE_DATA)| /* demime */
453 #ifdef EXPERIMENTAL_PRDR
455 #endif /* EXPERIMENTAL_PRDR */
456 (1<<ACL_WHERE_NOTSMTP)),
461 ~(1<<ACL_WHERE_DKIM), /* dkim_signers */
464 ~(1<<ACL_WHERE_DKIM), /* dkim_status */
467 #ifdef EXPERIMENTAL_DMARC
469 ~(1<<ACL_WHERE_DATA), /* dmarc_status */
472 (1<<ACL_WHERE_NOTSMTP)| /* dnslists */
473 (1<<ACL_WHERE_NOTSMTP_START),
476 ~((1<<ACL_WHERE_RCPT) /* domains */
477 #ifdef EXPERIMENTAL_PRDR
482 (1<<ACL_WHERE_NOTSMTP)| /* encrypted */
483 (1<<ACL_WHERE_CONNECT)|
484 (1<<ACL_WHERE_NOTSMTP_START)|
489 (1<<ACL_WHERE_NOTSMTP)| /* hosts */
490 (1<<ACL_WHERE_NOTSMTP_START),
493 ~((1<<ACL_WHERE_RCPT) /* local_parts */
494 #ifdef EXPERIMENTAL_PRDR
501 0, /* log_reject_target */
505 #ifdef WITH_CONTENT_SCAN
507 ~((1<<ACL_WHERE_DATA)| /* malware */
508 #ifdef EXPERIMENTAL_PRDR
510 #endif /* EXPERIMENTAL_PRDR */
511 (1<<ACL_WHERE_NOTSMTP)),
516 #ifdef WITH_CONTENT_SCAN
518 ~(1<<ACL_WHERE_MIME), /* mime_regex */
524 ~(1<<ACL_WHERE_RCPT), /* recipients */
526 #ifdef WITH_CONTENT_SCAN
528 ~((1<<ACL_WHERE_DATA)| /* regex */
529 #ifdef EXPERIMENTAL_PRDR
531 #endif /* EXPERIMENTAL_PRDR */
532 (1<<ACL_WHERE_NOTSMTP)|
533 (1<<ACL_WHERE_MIME)),
537 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* remove_header */
538 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
539 #ifdef EXPERIMENTAL_PRDR
542 (1<<ACL_WHERE_MIME)|(1<<ACL_WHERE_NOTSMTP)|
543 (1<<ACL_WHERE_NOTSMTP_START)),
545 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* sender_domains */
547 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
548 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
549 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
551 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* senders */
553 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
554 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
555 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
559 #ifdef WITH_CONTENT_SCAN
561 ~((1<<ACL_WHERE_DATA)| /* spam */
562 #ifdef EXPERIMENTAL_PRDR
564 #endif /* EXPERIMENTAL_PRDR */
565 (1<<ACL_WHERE_NOTSMTP)),
568 #ifdef EXPERIMENTAL_SPF
569 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* spf */
571 (1<<ACL_WHERE_MAILAUTH)|
572 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
573 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY)|
574 (1<<ACL_WHERE_NOTSMTP)|
575 (1<<ACL_WHERE_NOTSMTP_START),
577 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* spf_guess */
579 (1<<ACL_WHERE_MAILAUTH)|
580 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
581 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY)|
582 (1<<ACL_WHERE_NOTSMTP)|
583 (1<<ACL_WHERE_NOTSMTP_START),
588 /* Certain types of verify are always allowed, so we let it through
589 always and check in the verify function itself */
595 /* Bit map vector of which controls are not allowed at certain times. For
596 each control, there's a bitmap of dis-allowed times. For some, it is easier to
597 specify the negation of a small number of allowed times. */
599 static unsigned int control_forbids[] = {
601 ~((1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)), /* allow_auth_unadvertised */
603 #ifdef EXPERIMENTAL_BRIGHTMAIL
610 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* dkim_disable_verify */
611 #ifdef EXPERIMENTAL_PRDR
613 #endif /* EXPERIMENTAL_PRDR */
614 (1<<ACL_WHERE_NOTSMTP_START),
617 #ifdef EXPERIMENTAL_DMARC
618 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* dmarc_disable_verify */
619 (1<<ACL_WHERE_NOTSMTP_START),
620 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* dmarc_enable_forensic */
621 (1<<ACL_WHERE_NOTSMTP_START),
624 (1<<ACL_WHERE_NOTSMTP)|
625 (1<<ACL_WHERE_NOTSMTP_START)|
626 (1<<ACL_WHERE_NOTQUIT), /* dscp */
631 ~(1<<ACL_WHERE_RCPT), /* caseful_local_part */
634 ~(1<<ACL_WHERE_RCPT), /* caselower_local_part */
637 0, /* cutthrough_delivery */
639 (1<<ACL_WHERE_NOTSMTP)| /* enforce_sync */
640 (1<<ACL_WHERE_NOTSMTP_START),
642 (1<<ACL_WHERE_NOTSMTP)| /* no_enforce_sync */
643 (1<<ACL_WHERE_NOTSMTP_START),
646 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* freeze */
647 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
648 // (1<<ACL_WHERE_PRDR)| /* Not allow one user to freeze for all */
649 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)),
652 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* queue_only */
653 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
654 // (1<<ACL_WHERE_PRDR)| /* Not allow one user to freeze for all */
655 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)),
658 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* submission */
659 (1<<ACL_WHERE_PREDATA)),
662 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* suppress_local_fixups */
663 (1<<ACL_WHERE_PREDATA)|
664 (1<<ACL_WHERE_NOTSMTP_START)),
666 #ifdef WITH_CONTENT_SCAN
668 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* no_mbox_unspool */
669 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
670 // (1<<ACL_WHERE_PRDR)| /* Not allow one user to freeze for all */
671 (1<<ACL_WHERE_MIME)),
675 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakedefer */
676 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
677 #ifdef EXPERIMENTAL_PRDR
679 #endif /* EXPERIMENTAL_PRDR */
680 (1<<ACL_WHERE_MIME)),
683 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakereject */
684 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
685 #ifdef EXPERIMENTAL_PRDR
687 #endif /* EXPERIMENTAL_PRDR */
688 (1<<ACL_WHERE_MIME)),
690 (1<<ACL_WHERE_NOTSMTP)| /* no_multiline */
691 (1<<ACL_WHERE_NOTSMTP_START),
693 (1<<ACL_WHERE_NOTSMTP)| /* no_pipelining */
694 (1<<ACL_WHERE_NOTSMTP_START),
696 (1<<ACL_WHERE_NOTSMTP)| /* no_delay_flush */
697 (1<<ACL_WHERE_NOTSMTP_START),
699 (1<<ACL_WHERE_NOTSMTP)| /* no_callout_flush */
700 (1<<ACL_WHERE_NOTSMTP_START)
703 /* Structure listing various control arguments, with their characteristics. */
705 typedef struct control_def {
707 int value; /* CONTROL_xxx value */
708 BOOL has_option; /* Has /option(s) following */
711 static control_def controls_list[] = {
712 { US"allow_auth_unadvertised", CONTROL_AUTH_UNADVERTISED, FALSE },
713 #ifdef EXPERIMENTAL_BRIGHTMAIL
714 { US"bmi_run", CONTROL_BMI_RUN, FALSE },
716 { US"debug", CONTROL_DEBUG, TRUE },
718 { US"dkim_disable_verify", CONTROL_DKIM_VERIFY, FALSE },
720 #ifdef EXPERIMENTAL_DMARC
721 { US"dmarc_disable_verify", CONTROL_DMARC_VERIFY, FALSE },
722 { US"dmarc_enable_forensic", CONTROL_DMARC_FORENSIC, FALSE },
724 { US"dscp", CONTROL_DSCP, TRUE },
725 { US"caseful_local_part", CONTROL_CASEFUL_LOCAL_PART, FALSE },
726 { US"caselower_local_part", CONTROL_CASELOWER_LOCAL_PART, FALSE },
727 { US"enforce_sync", CONTROL_ENFORCE_SYNC, FALSE },
728 { US"freeze", CONTROL_FREEZE, TRUE },
729 { US"no_callout_flush", CONTROL_NO_CALLOUT_FLUSH, FALSE },
730 { US"no_delay_flush", CONTROL_NO_DELAY_FLUSH, FALSE },
731 { US"no_enforce_sync", CONTROL_NO_ENFORCE_SYNC, FALSE },
732 { US"no_multiline_responses", CONTROL_NO_MULTILINE, FALSE },
733 { US"no_pipelining", CONTROL_NO_PIPELINING, FALSE },
734 { US"queue_only", CONTROL_QUEUE_ONLY, FALSE },
735 #ifdef WITH_CONTENT_SCAN
736 { US"no_mbox_unspool", CONTROL_NO_MBOX_UNSPOOL, FALSE },
738 { US"fakedefer", CONTROL_FAKEDEFER, TRUE },
739 { US"fakereject", CONTROL_FAKEREJECT, TRUE },
740 { US"submission", CONTROL_SUBMISSION, TRUE },
741 { US"suppress_local_fixups", CONTROL_SUPPRESS_LOCAL_FIXUPS, FALSE },
742 { US"cutthrough_delivery", CONTROL_CUTTHROUGH_DELIVERY, FALSE }
745 /* Support data structures for Client SMTP Authorization. acl_verify_csa()
746 caches its result in a tree to avoid repeated DNS queries. The result is an
747 integer code which is used as an index into the following tables of
748 explanatory strings and verification return codes. */
750 static tree_node *csa_cache = NULL;
752 enum { CSA_UNKNOWN, CSA_OK, CSA_DEFER_SRV, CSA_DEFER_ADDR,
753 CSA_FAIL_EXPLICIT, CSA_FAIL_DOMAIN, CSA_FAIL_NOADDR, CSA_FAIL_MISMATCH };
755 /* The acl_verify_csa() return code is translated into an acl_verify() return
756 code using the following table. It is OK unless the client is definitely not
757 authorized. This is because CSA is supposed to be optional for sending sites,
758 so recipients should not be too strict about checking it - especially because
759 DNS problems are quite likely to occur. It's possible to use $csa_status in
760 further ACL conditions to distinguish ok, unknown, and defer if required, but
761 the aim is to make the usual configuration simple. */
763 static int csa_return_code[] = {
765 FAIL, FAIL, FAIL, FAIL
768 static uschar *csa_status_string[] = {
769 US"unknown", US"ok", US"defer", US"defer",
770 US"fail", US"fail", US"fail", US"fail"
773 static uschar *csa_reason_string[] = {
776 US"deferred (SRV lookup failed)",
777 US"deferred (target address lookup failed)",
778 US"failed (explicit authorization required)",
779 US"failed (host name not authorized)",
780 US"failed (no authorized addresses)",
781 US"failed (client address mismatch)"
784 /* Options for the ratelimit condition. Note that there are two variants of
785 the per_rcpt option, depending on the ACL that is used to measure the rate.
786 However any ACL must be able to look up per_rcpt rates in /noupdate mode,
787 so the two variants must have the same internal representation as well as
788 the same configuration string. */
791 RATE_PER_WHAT, RATE_PER_CLASH, RATE_PER_ADDR, RATE_PER_BYTE, RATE_PER_CMD,
792 RATE_PER_CONN, RATE_PER_MAIL, RATE_PER_RCPT, RATE_PER_ALLRCPTS
795 #define RATE_SET(var,new) \
796 (((var) == RATE_PER_WHAT) ? ((var) = RATE_##new) : ((var) = RATE_PER_CLASH))
798 static uschar *ratelimit_option_string[] = {
799 US"?", US"!", US"per_addr", US"per_byte", US"per_cmd",
800 US"per_conn", US"per_mail", US"per_rcpt", US"per_rcpt"
803 /* Enable recursion between acl_check_internal() and acl_check_condition() */
805 static int acl_check_wargs(int, address_item *, uschar *, int, uschar **,
809 /*************************************************
810 * Pick out name from list *
811 *************************************************/
813 /* Use a binary chop method
820 Returns: offset in list, or -1 if not found
824 acl_checkname(uschar *name, uschar **list, int end)
830 int mid = (start + end)/2;
831 int c = Ustrcmp(name, list[mid]);
832 if (c == 0) return mid;
833 if (c < 0) end = mid; else start = mid + 1;
840 /*************************************************
841 * Read and parse one ACL *
842 *************************************************/
844 /* This function is called both from readconf in order to parse the ACLs in the
845 configuration file, and also when an ACL is encountered dynamically (e.g. as
846 the result of an expansion). It is given a function to call in order to
847 retrieve the lines of the ACL. This function handles skipping comments and
848 blank lines (where relevant).
851 func function to get next line of ACL
852 error where to put an error message
854 Returns: pointer to ACL, or NULL
855 NULL can be legal (empty ACL); in this case error will be NULL
859 acl_read(uschar *(*func)(void), uschar **error)
861 acl_block *yield = NULL;
862 acl_block **lastp = &yield;
863 acl_block *this = NULL;
864 acl_condition_block *cond;
865 acl_condition_block **condp = NULL;
870 while ((s = (*func)()) != NULL)
873 BOOL negated = FALSE;
874 uschar *saveline = s;
877 /* Conditions (but not verbs) are allowed to be negated by an initial
880 while (isspace(*s)) s++;
887 /* Read the name of a verb or a condition, or the start of a new ACL, which
888 can be started by a name, or by a macro definition. */
890 s = readconf_readname(name, sizeof(name), s);
891 if (*s == ':' || (isupper(name[0]) && *s == '=')) return yield;
893 /* If a verb is unrecognized, it may be another condition or modifier that
894 continues the previous verb. */
896 v = acl_checkname(name, verbs, sizeof(verbs)/sizeof(char *));
901 *error = string_sprintf("unknown ACL verb \"%s\" in \"%s\"", name,
913 *error = string_sprintf("malformed ACL line \"%s\"", saveline);
916 this = store_get(sizeof(acl_block));
918 lastp = &(this->next);
921 this->condition = NULL;
922 condp = &(this->condition);
923 if (*s == 0) continue; /* No condition on this line */
929 s = readconf_readname(name, sizeof(name), s); /* Condition name */
932 /* Handle a condition or modifier. */
934 c = acl_checkname(name, conditions, sizeof(conditions)/sizeof(char *));
937 *error = string_sprintf("unknown ACL condition/modifier in \"%s\"",
942 /* The modifiers may not be negated */
944 if (negated && cond_modifiers[c])
946 *error = string_sprintf("ACL error: negation is not allowed with "
947 "\"%s\"", conditions[c]);
951 /* ENDPASS may occur only with ACCEPT or DISCARD. */
953 if (c == ACLC_ENDPASS &&
954 this->verb != ACL_ACCEPT &&
955 this->verb != ACL_DISCARD)
957 *error = string_sprintf("ACL error: \"%s\" is not allowed with \"%s\"",
958 conditions[c], verbs[this->verb]);
962 cond = store_get(sizeof(acl_condition_block));
965 cond->u.negated = negated;
968 condp = &(cond->next);
970 /* The "set" modifier is different in that its argument is "name=value"
971 rather than just a value, and we can check the validity of the name, which
972 gives us a variable name to insert into the data block. The original ACL
973 variable names were acl_c0 ... acl_c9 and acl_m0 ... acl_m9. This was
974 extended to 20 of each type, but after that people successfully argued for
975 arbitrary names. In the new scheme, the names must start with acl_c or acl_m.
976 After that, we allow alphanumerics and underscores, but the first character
977 after c or m must be a digit or an underscore. This retains backwards
984 if (Ustrncmp(s, "acl_c", 5) != 0 &&
985 Ustrncmp(s, "acl_m", 5) != 0)
987 *error = string_sprintf("invalid variable name after \"set\" in ACL "
988 "modifier \"set %s\" (must start \"acl_c\" or \"acl_m\")", s);
993 if (!isdigit(*endptr) && *endptr != '_')
995 *error = string_sprintf("invalid variable name after \"set\" in ACL "
996 "modifier \"set %s\" (digit or underscore must follow acl_c or acl_m)",
1001 while (*endptr != 0 && *endptr != '=' && !isspace(*endptr))
1003 if (!isalnum(*endptr) && *endptr != '_')
1005 *error = string_sprintf("invalid character \"%c\" in variable name "
1006 "in ACL modifier \"set %s\"", *endptr, s);
1012 cond->u.varname = string_copyn(s + 4, endptr - s - 4);
1014 while (isspace(*s)) s++;
1017 /* For "set", we are now positioned for the data. For the others, only
1018 "endpass" has no data */
1020 if (c != ACLC_ENDPASS)
1024 *error = string_sprintf("\"=\" missing after ACL \"%s\" %s", name,
1025 cond_modifiers[c]? US"modifier" : US"condition");
1028 while (isspace(*s)) s++;
1029 cond->arg = string_copy(s);
1038 /*************************************************
1039 * Set up added header line(s) *
1040 *************************************************/
1042 /* This function is called by the add_header modifier, and also from acl_warn()
1043 to implement the now-deprecated way of adding header lines using "message" on a
1044 "warn" verb. The argument is treated as a sequence of header lines which are
1045 added to a chain, provided there isn't an identical one already there.
1047 Argument: string of header lines
1052 setup_header(uschar *hstring)
1055 int hlen = Ustrlen(hstring);
1057 /* Ignore any leading newlines */
1058 while (*hstring == '\n') hstring++, hlen--;
1060 /* An empty string does nothing; ensure exactly one final newline. */
1061 if (hlen <= 0) return;
1062 if (hstring[--hlen] != '\n') hstring = string_sprintf("%s\n", hstring);
1063 else while(hstring[--hlen] == '\n') hstring[hlen+1] = '\0';
1065 /* Loop for multiple header lines, taking care about continuations */
1067 for (p = q = hstring; *p != 0; )
1070 int newtype = htype_add_bot;
1071 header_line **hptr = &acl_added_headers;
1073 /* Find next header line within the string */
1077 q = Ustrchr(q, '\n');
1078 if (*(++q) != ' ' && *q != '\t') break;
1081 /* If the line starts with a colon, interpret the instruction for where to
1082 add it. This temporarily sets up a new type. */
1086 if (strncmpic(p, US":after_received:", 16) == 0)
1088 newtype = htype_add_rec;
1091 else if (strncmpic(p, US":at_start_rfc:", 14) == 0)
1093 newtype = htype_add_rfc;
1096 else if (strncmpic(p, US":at_start:", 10) == 0)
1098 newtype = htype_add_top;
1101 else if (strncmpic(p, US":at_end:", 8) == 0)
1103 newtype = htype_add_bot;
1106 while (*p == ' ' || *p == '\t') p++;
1109 /* See if this line starts with a header name, and if not, add X-ACL-Warn:
1110 to the front of it. */
1112 for (s = p; s < q - 1; s++)
1114 if (*s == ':' || !isgraph(*s)) break;
1117 s = string_sprintf("%s%.*s", (*s == ':')? "" : "X-ACL-Warn: ", (int) (q - p), p);
1120 /* See if this line has already been added */
1122 while (*hptr != NULL)
1124 if (Ustrncmp((*hptr)->text, s, hlen) == 0) break;
1125 hptr = &((*hptr)->next);
1128 /* Add if not previously present */
1132 header_line *h = store_get(sizeof(header_line));
1141 /* Advance for next header line within the string */
1149 /*************************************************
1150 * List the added header lines *
1151 *************************************************/
1155 uschar * ret = NULL;
1156 header_line * h = acl_added_headers;
1162 if (!h) return NULL;
1167 while ((cp = Ustrchr(s, '\n')) != NULL)
1169 if (cp[1] == '\0') break;
1171 /* contains embedded newline; needs doubling */
1172 ret = string_cat(ret, &size, &ptr, s, cp-s+1);
1173 ret = string_cat(ret, &size, &ptr, US"\n", 1);
1176 /* last bit of header */
1178 ret = string_cat(ret, &size, &ptr, s, cp-s+1); /* newline-sep list */
1180 while((h = h->next));
1182 ret[ptr-1] = '\0'; /* overwrite last newline */
1187 /*************************************************
1188 * Set up removed header line(s) *
1189 *************************************************/
1191 /* This function is called by the remove_header modifier. The argument is
1192 treated as a sequence of header names which are added to a colon separated
1193 list, provided there isn't an identical one already there.
1195 Argument: string of header names
1200 setup_remove_header(uschar *hnames)
1204 if (acl_removed_headers == NULL)
1205 acl_removed_headers = hnames;
1207 acl_removed_headers = string_sprintf("%s : %s", acl_removed_headers, hnames);
1213 /*************************************************
1215 *************************************************/
1217 /* This function is called when a WARN verb's conditions are true. It adds to
1218 the message's headers, and/or writes information to the log. In each case, this
1219 only happens once (per message for headers, per connection for log).
1221 ** NOTE: The header adding action using the "message" setting is historic, and
1222 its use is now deprecated. The new add_header modifier should be used instead.
1225 where ACL_WHERE_xxxx indicating which ACL this is
1226 user_message message for adding to headers
1227 log_message message for logging, if different
1233 acl_warn(int where, uschar *user_message, uschar *log_message)
1235 if (log_message != NULL && log_message != user_message)
1238 string_item *logged;
1240 text = string_sprintf("%s Warning: %s", host_and_ident(TRUE),
1241 string_printing(log_message));
1243 /* If a sender verification has failed, and the log message is "sender verify
1244 failed", add the failure message. */
1246 if (sender_verified_failed != NULL &&
1247 sender_verified_failed->message != NULL &&
1248 strcmpic(log_message, US"sender verify failed") == 0)
1249 text = string_sprintf("%s: %s", text, sender_verified_failed->message);
1251 /* Search previously logged warnings. They are kept in malloc
1252 store so they can be freed at the start of a new message. */
1254 for (logged = acl_warn_logged; logged != NULL; logged = logged->next)
1255 if (Ustrcmp(logged->text, text) == 0) break;
1259 int length = Ustrlen(text) + 1;
1260 log_write(0, LOG_MAIN, "%s", text);
1261 logged = store_malloc(sizeof(string_item) + length);
1262 logged->text = (uschar *)logged + sizeof(string_item);
1263 memcpy(logged->text, text, length);
1264 logged->next = acl_warn_logged;
1265 acl_warn_logged = logged;
1269 /* If there's no user message, we are done. */
1271 if (user_message == NULL) return;
1273 /* If this isn't a message ACL, we can't do anything with a user message.
1276 if (where > ACL_WHERE_NOTSMTP)
1278 log_write(0, LOG_MAIN|LOG_PANIC, "ACL \"warn\" with \"message\" setting "
1279 "found in a non-message (%s) ACL: cannot specify header lines here: "
1280 "message ignored", acl_wherenames[where]);
1284 /* The code for setting up header lines is now abstracted into a separate
1285 function so that it can be used for the add_header modifier as well. */
1287 setup_header(user_message);
1292 /*************************************************
1293 * Verify and check reverse DNS *
1294 *************************************************/
1296 /* Called from acl_verify() below. We look up the host name(s) of the client IP
1297 address if this has not yet been done. The host_name_lookup() function checks
1298 that one of these names resolves to an address list that contains the client IP
1299 address, so we don't actually have to do the check here.
1302 user_msgptr pointer for user message
1303 log_msgptr pointer for log message
1305 Returns: OK verification condition succeeded
1306 FAIL verification failed
1307 DEFER there was a problem verifying
1311 acl_verify_reverse(uschar **user_msgptr, uschar **log_msgptr)
1315 user_msgptr = user_msgptr; /* stop compiler warning */
1317 /* Previous success */
1319 if (sender_host_name != NULL) return OK;
1321 /* Previous failure */
1323 if (host_lookup_failed)
1325 *log_msgptr = string_sprintf("host lookup failed%s", host_lookup_msg);
1329 /* Need to do a lookup */
1332 debug_printf("looking up host name to force name/address consistency check\n");
1334 if ((rc = host_name_lookup()) != OK)
1336 *log_msgptr = (rc == DEFER)?
1337 US"host lookup deferred for reverse lookup check"
1339 string_sprintf("host lookup failed for reverse lookup check%s",
1341 return rc; /* DEFER or FAIL */
1344 host_build_sender_fullhost();
1350 /*************************************************
1351 * Check client IP address matches CSA target *
1352 *************************************************/
1354 /* Called from acl_verify_csa() below. This routine scans a section of a DNS
1355 response for address records belonging to the CSA target hostname. The section
1356 is specified by the reset argument, either RESET_ADDITIONAL or RESET_ANSWERS.
1357 If one of the addresses matches the client's IP address, then the client is
1358 authorized by CSA. If there are target IP addresses but none of them match
1359 then the client is using an unauthorized IP address. If there are no target IP
1360 addresses then the client cannot be using an authorized IP address. (This is
1361 an odd configuration - why didn't the SRV record have a weight of 1 instead?)
1364 dnsa the DNS answer block
1365 dnss a DNS scan block for us to use
1366 reset option specifing what portion to scan, as described above
1367 target the target hostname to use for matching RR names
1369 Returns: CSA_OK successfully authorized
1370 CSA_FAIL_MISMATCH addresses found but none matched
1371 CSA_FAIL_NOADDR no target addresses found
1375 acl_verify_csa_address(dns_answer *dnsa, dns_scan *dnss, int reset,
1381 BOOL target_found = FALSE;
1383 for (rr = dns_next_rr(dnsa, dnss, reset);
1385 rr = dns_next_rr(dnsa, dnss, RESET_NEXT))
1387 /* Check this is an address RR for the target hostname. */
1391 && rr->type != T_AAAA
1398 if (strcmpic(target, rr->name) != 0) continue;
1400 target_found = TRUE;
1402 /* Turn the target address RR into a list of textual IP addresses and scan
1403 the list. There may be more than one if it is an A6 RR. */
1405 for (da = dns_address_from_rr(dnsa, rr); da != NULL; da = da->next)
1407 /* If the client IP address matches the target IP address, it's good! */
1409 DEBUG(D_acl) debug_printf("CSA target address is %s\n", da->address);
1411 if (strcmpic(sender_host_address, da->address) == 0) return CSA_OK;
1415 /* If we found some target addresses but none of them matched, the client is
1416 using an unauthorized IP address, otherwise the target has no authorized IP
1419 if (target_found) return CSA_FAIL_MISMATCH;
1420 else return CSA_FAIL_NOADDR;
1425 /*************************************************
1426 * Verify Client SMTP Authorization *
1427 *************************************************/
1429 /* Called from acl_verify() below. This routine calls dns_lookup_special()
1430 to find the CSA SRV record corresponding to the domain argument, or
1431 $sender_helo_name if no argument is provided. It then checks that the
1432 client is authorized, and that its IP address corresponds to the SRV
1433 target's address by calling acl_verify_csa_address() above. The address
1434 should have been returned in the DNS response's ADDITIONAL section, but if
1435 not we perform another DNS lookup to get it.
1438 domain pointer to optional parameter following verify = csa
1440 Returns: CSA_UNKNOWN no valid CSA record found
1441 CSA_OK successfully authorized
1442 CSA_FAIL_* client is definitely not authorized
1443 CSA_DEFER_* there was a DNS problem
1447 acl_verify_csa(uschar *domain)
1451 int priority, weight, port;
1458 /* Work out the domain we are using for the CSA lookup. The default is the
1459 client's HELO domain. If the client has not said HELO, use its IP address
1460 instead. If it's a local client (exim -bs), CSA isn't applicable. */
1462 while (isspace(*domain) && *domain != '\0') ++domain;
1463 if (*domain == '\0') domain = sender_helo_name;
1464 if (domain == NULL) domain = sender_host_address;
1465 if (sender_host_address == NULL) return CSA_UNKNOWN;
1467 /* If we have an address literal, strip off the framing ready for turning it
1468 into a domain. The framing consists of matched square brackets possibly
1469 containing a keyword and a colon before the actual IP address. */
1471 if (domain[0] == '[')
1473 uschar *start = Ustrchr(domain, ':');
1474 if (start == NULL) start = domain;
1475 domain = string_copyn(start + 1, Ustrlen(start) - 2);
1478 /* Turn domains that look like bare IP addresses into domains in the reverse
1479 DNS. This code also deals with address literals and $sender_host_address. It's
1480 not quite kosher to treat bare domains such as EHLO 192.0.2.57 the same as
1481 address literals, but it's probably the most friendly thing to do. This is an
1482 extension to CSA, so we allow it to be turned off for proper conformance. */
1484 if (string_is_ip_address(domain, NULL) != 0)
1486 if (!dns_csa_use_reverse) return CSA_UNKNOWN;
1487 dns_build_reverse(domain, target);
1491 /* Find out if we've already done the CSA check for this domain. If we have,
1492 return the same result again. Otherwise build a new cached result structure
1493 for this domain. The name is filled in now, and the value is filled in when
1494 we return from this function. */
1496 t = tree_search(csa_cache, domain);
1497 if (t != NULL) return t->data.val;
1499 t = store_get_perm(sizeof(tree_node) + Ustrlen(domain));
1500 Ustrcpy(t->name, domain);
1501 (void)tree_insertnode(&csa_cache, t);
1503 /* Now we are ready to do the actual DNS lookup(s). */
1506 switch (dns_special_lookup(&dnsa, domain, T_CSA, &found))
1508 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1511 return t->data.val = CSA_DEFER_SRV;
1513 /* If we found nothing, the client's authorization is unknown. */
1517 return t->data.val = CSA_UNKNOWN;
1519 /* We got something! Go on to look at the reply in more detail. */
1525 /* Scan the reply for well-formed CSA SRV records. */
1527 for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS);
1529 rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT))
1531 if (rr->type != T_SRV) continue;
1533 /* Extract the numerical SRV fields (p is incremented) */
1536 GETSHORT(priority, p);
1537 GETSHORT(weight, p);
1541 debug_printf("CSA priority=%d weight=%d port=%d\n", priority, weight, port);
1543 /* Check the CSA version number */
1545 if (priority != 1) continue;
1547 /* If the domain does not have a CSA SRV record of its own (i.e. the domain
1548 found by dns_special_lookup() is a parent of the one we asked for), we check
1549 the subdomain assertions in the port field. At the moment there's only one
1550 assertion: legitimate SMTP clients are all explicitly authorized with CSA
1551 SRV records of their own. */
1553 if (found != domain)
1556 return t->data.val = CSA_FAIL_EXPLICIT;
1558 return t->data.val = CSA_UNKNOWN;
1561 /* This CSA SRV record refers directly to our domain, so we check the value
1562 in the weight field to work out the domain's authorization. 0 and 1 are
1563 unauthorized; 3 means the client is authorized but we can't check the IP
1564 address in order to authenticate it, so we treat it as unknown; values
1565 greater than 3 are undefined. */
1567 if (weight < 2) return t->data.val = CSA_FAIL_DOMAIN;
1569 if (weight > 2) continue;
1571 /* Weight == 2, which means the domain is authorized. We must check that the
1572 client's IP address is listed as one of the SRV target addresses. Save the
1573 target hostname then break to scan the additional data for its addresses. */
1575 (void)dn_expand(dnsa.answer, dnsa.answer + dnsa.answerlen, p,
1576 (DN_EXPAND_ARG4_TYPE)target, sizeof(target));
1578 DEBUG(D_acl) debug_printf("CSA target is %s\n", target);
1583 /* If we didn't break the loop then no appropriate records were found. */
1585 if (rr == NULL) return t->data.val = CSA_UNKNOWN;
1587 /* Do not check addresses if the target is ".", in accordance with RFC 2782.
1588 A target of "." indicates there are no valid addresses, so the client cannot
1589 be authorized. (This is an odd configuration because weight=2 target=. is
1590 equivalent to weight=1, but we check for it in order to keep load off the
1591 root name servers.) Note that dn_expand() turns "." into "". */
1593 if (Ustrcmp(target, "") == 0) return t->data.val = CSA_FAIL_NOADDR;
1595 /* Scan the additional section of the CSA SRV reply for addresses belonging
1596 to the target. If the name server didn't return any additional data (e.g.
1597 because it does not fully support SRV records), we need to do another lookup
1598 to obtain the target addresses; otherwise we have a definitive result. */
1600 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ADDITIONAL, target);
1601 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1603 /* The DNS lookup type corresponds to the IP version used by the client. */
1606 if (Ustrchr(sender_host_address, ':') != NULL)
1609 #endif /* HAVE_IPV6 */
1613 #if HAVE_IPV6 && defined(SUPPORT_A6)
1617 switch (dns_lookup(&dnsa, target, type, NULL))
1619 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1622 return t->data.val = CSA_DEFER_ADDR;
1624 /* If the query succeeded, scan the addresses and return the result. */
1627 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ANSWERS, target);
1628 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1629 /* else fall through */
1631 /* If the target has no IP addresses, the client cannot have an authorized
1632 IP address. However, if the target site uses A6 records (not AAAA records)
1633 we have to do yet another lookup in order to check them. */
1638 #if HAVE_IPV6 && defined(SUPPORT_A6)
1639 if (type == T_AAAA) { type = T_A6; goto DNS_LOOKUP_AGAIN; }
1642 return t->data.val = CSA_FAIL_NOADDR;
1648 /*************************************************
1649 * Handle verification (address & other) *
1650 *************************************************/
1652 enum { VERIFY_REV_HOST_LKUP, VERIFY_CERT, VERIFY_HELO, VERIFY_CSA, VERIFY_HDR_SYNTAX,
1653 VERIFY_NOT_BLIND, VERIFY_HDR_SNDR, VERIFY_SNDR, VERIFY_RCPT,
1654 VERIFY_HDR_NAMES_ASCII
1659 unsigned where_allowed; /* bitmap */
1660 BOOL no_options; /* Never has /option(s) following */
1661 unsigned alt_opt_sep; /* >0 Non-/ option separator (custom parser) */
1663 static verify_type_t verify_type_list[] = {
1664 { US"reverse_host_lookup", VERIFY_REV_HOST_LKUP, ~0, TRUE, 0 },
1665 { US"certificate", VERIFY_CERT, ~0, TRUE, 0 },
1666 { US"helo", VERIFY_HELO, ~0, TRUE, 0 },
1667 { US"csa", VERIFY_CSA, ~0, FALSE, 0 },
1668 { US"header_syntax", VERIFY_HDR_SYNTAX, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), TRUE, 0 },
1669 { US"not_blind", VERIFY_NOT_BLIND, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), TRUE, 0 },
1670 { US"header_sender", VERIFY_HDR_SNDR, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), FALSE, 0 },
1671 { US"sender", VERIFY_SNDR, (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)
1672 |(1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP),
1674 { US"recipient", VERIFY_RCPT, (1<<ACL_WHERE_RCPT), FALSE, 0 },
1675 { US"header_names_ascii", VERIFY_HDR_NAMES_ASCII, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), TRUE, 0 }
1679 enum { CALLOUT_DEFER_OK, CALLOUT_NOCACHE, CALLOUT_RANDOM, CALLOUT_USE_SENDER,
1680 CALLOUT_USE_POSTMASTER, CALLOUT_POSTMASTER, CALLOUT_FULLPOSTMASTER,
1681 CALLOUT_MAILFROM, CALLOUT_POSTMASTER_MAILFROM, CALLOUT_MAXWAIT, CALLOUT_CONNECT,
1688 BOOL has_option; /* Has =option(s) following */
1689 BOOL timeval; /* Has a time value */
1691 static callout_opt_t callout_opt_list[] = {
1692 { US"defer_ok", CALLOUT_DEFER_OK, 0, FALSE, FALSE },
1693 { US"no_cache", CALLOUT_NOCACHE, vopt_callout_no_cache, FALSE, FALSE },
1694 { US"random", CALLOUT_RANDOM, vopt_callout_random, FALSE, FALSE },
1695 { US"use_sender", CALLOUT_USE_SENDER, vopt_callout_recipsender, FALSE, FALSE },
1696 { US"use_postmaster", CALLOUT_USE_POSTMASTER,vopt_callout_recippmaster, FALSE, FALSE },
1697 { US"postmaster_mailfrom",CALLOUT_POSTMASTER_MAILFROM,0, TRUE, FALSE },
1698 { US"postmaster", CALLOUT_POSTMASTER, 0, FALSE, FALSE },
1699 { US"fullpostmaster", CALLOUT_FULLPOSTMASTER,vopt_callout_fullpm, FALSE, FALSE },
1700 { US"mailfrom", CALLOUT_MAILFROM, 0, TRUE, FALSE },
1701 { US"maxwait", CALLOUT_MAXWAIT, 0, TRUE, TRUE },
1702 { US"connect", CALLOUT_CONNECT, 0, TRUE, TRUE },
1703 { NULL, CALLOUT_TIME, 0, FALSE, TRUE }
1708 /* This function implements the "verify" condition. It is called when
1709 encountered in any ACL, because some tests are almost always permitted. Some
1710 just don't make sense, and always fail (for example, an attempt to test a host
1711 lookup for a non-TCP/IP message). Others are restricted to certain ACLs.
1714 where where called from
1715 addr the recipient address that the ACL is handling, or NULL
1716 arg the argument of "verify"
1717 user_msgptr pointer for user message
1718 log_msgptr pointer for log message
1719 basic_errno where to put verify errno
1721 Returns: OK verification condition succeeded
1722 FAIL verification failed
1723 DEFER there was a problem verifying
1728 acl_verify(int where, address_item *addr, uschar *arg,
1729 uschar **user_msgptr, uschar **log_msgptr, int *basic_errno)
1733 int callout_overall = -1;
1734 int callout_connect = -1;
1735 int verify_options = 0;
1737 BOOL verify_header_sender = FALSE;
1738 BOOL defer_ok = FALSE;
1739 BOOL callout_defer_ok = FALSE;
1740 BOOL no_details = FALSE;
1741 BOOL success_on_redirect = FALSE;
1742 address_item *sender_vaddr = NULL;
1743 uschar *verify_sender_address = NULL;
1744 uschar *pm_mailfrom = NULL;
1745 uschar *se_mailfrom = NULL;
1747 /* Some of the verify items have slash-separated options; some do not. Diagnose
1748 an error if options are given for items that don't expect them.
1751 uschar *slash = Ustrchr(arg, '/');
1753 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
1756 if (ss == NULL) goto BAD_VERIFY;
1758 /* Handle name/address consistency verification in a separate function. */
1760 for (vp= verify_type_list;
1761 (char *)vp < (char *)verify_type_list + sizeof(verify_type_list);
1764 if (vp->alt_opt_sep ? strncmpic(ss, vp->name, vp->alt_opt_sep) == 0
1765 : strcmpic (ss, vp->name) == 0)
1767 if ((char *)vp >= (char *)verify_type_list + sizeof(verify_type_list))
1770 if (vp->no_options && slash != NULL)
1772 *log_msgptr = string_sprintf("unexpected '/' found in \"%s\" "
1773 "(this verify item has no options)", arg);
1776 if (!(vp->where_allowed & (1<<where)))
1778 *log_msgptr = string_sprintf("cannot verify %s in ACL for %s", vp->name, acl_wherenames[where]);
1783 case VERIFY_REV_HOST_LKUP:
1784 if (sender_host_address == NULL) return OK;
1785 return acl_verify_reverse(user_msgptr, log_msgptr);
1788 /* TLS certificate verification is done at STARTTLS time; here we just
1789 test whether it was successful or not. (This is for optional verification; for
1790 mandatory verification, the connection doesn't last this long.) */
1792 if (tls_in.certificate_verified) return OK;
1793 *user_msgptr = US"no verified certificate";
1797 /* We can test the result of optional HELO verification that might have
1798 occurred earlier. If not, we can attempt the verification now. */
1800 if (!helo_verified && !helo_verify_failed) smtp_verify_helo();
1801 return helo_verified? OK : FAIL;
1804 /* Do Client SMTP Authorization checks in a separate function, and turn the
1805 result code into user-friendly strings. */
1807 rc = acl_verify_csa(list);
1808 *log_msgptr = *user_msgptr = string_sprintf("client SMTP authorization %s",
1809 csa_reason_string[rc]);
1810 csa_status = csa_status_string[rc];
1811 DEBUG(D_acl) debug_printf("CSA result %s\n", csa_status);
1812 return csa_return_code[rc];
1814 case VERIFY_HDR_SYNTAX:
1815 /* Check that all relevant header lines have the correct syntax. If there is
1816 a syntax error, we return details of the error to the sender if configured to
1817 send out full details. (But a "message" setting on the ACL can override, as
1820 rc = verify_check_headers(log_msgptr);
1821 if (rc != OK && smtp_return_error_details && *log_msgptr != NULL)
1822 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1825 case VERIFY_HDR_NAMES_ASCII:
1826 /* Check that all header names are true 7 bit strings
1827 See RFC 5322, 2.2. and RFC 6532, 3. */
1829 rc = verify_check_header_names_ascii(log_msgptr);
1830 if (rc != OK && smtp_return_error_details && *log_msgptr != NULL)
1831 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1834 case VERIFY_NOT_BLIND:
1835 /* Check that no recipient of this message is "blind", that is, every envelope
1836 recipient must be mentioned in either To: or Cc:. */
1838 rc = verify_check_notblind();
1841 *log_msgptr = string_sprintf("bcc recipient detected");
1842 if (smtp_return_error_details)
1843 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1847 /* The remaining verification tests check recipient and sender addresses,
1848 either from the envelope or from the header. There are a number of
1849 slash-separated options that are common to all of them. */
1851 case VERIFY_HDR_SNDR:
1852 verify_header_sender = TRUE;
1856 /* In the case of a sender, this can optionally be followed by an address to use
1857 in place of the actual sender (rare special-case requirement). */
1861 verify_sender_address = sender_address;
1864 while (isspace(*s)) s++;
1865 if (*s++ != '=') goto BAD_VERIFY;
1866 while (isspace(*s)) s++;
1867 verify_sender_address = string_copy(s);
1878 /* Remaining items are optional; they apply to sender and recipient
1879 verification, including "header sender" verification. */
1881 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size))
1884 if (strcmpic(ss, US"defer_ok") == 0) defer_ok = TRUE;
1885 else if (strcmpic(ss, US"no_details") == 0) no_details = TRUE;
1886 else if (strcmpic(ss, US"success_on_redirect") == 0) success_on_redirect = TRUE;
1888 /* These two old options are left for backwards compatibility */
1890 else if (strcmpic(ss, US"callout_defer_ok") == 0)
1892 callout_defer_ok = TRUE;
1893 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1896 else if (strcmpic(ss, US"check_postmaster") == 0)
1899 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1902 /* The callout option has a number of sub-options, comma separated */
1904 else if (strncmpic(ss, US"callout", 7) == 0)
1906 callout = CALLOUT_TIMEOUT_DEFAULT;
1910 while (isspace(*ss)) ss++;
1916 while (isspace(*ss)) ss++;
1918 while ((opt = string_nextinlist(&ss, &optsep, buffer, sizeof(buffer)))
1922 double period = 1.0F;
1924 for (op= callout_opt_list; op->name; op++)
1925 if (strncmpic(opt, op->name, Ustrlen(op->name)) == 0)
1928 verify_options |= op->flag;
1931 opt += Ustrlen(op->name);
1932 while (isspace(*opt)) opt++;
1935 *log_msgptr = string_sprintf("'=' expected after "
1936 "\"%s\" in ACL verify condition \"%s\"", op->name, arg);
1939 while (isspace(*opt)) opt++;
1943 period = readconf_readtime(opt, 0, FALSE);
1946 *log_msgptr = string_sprintf("bad time value in ACL condition "
1947 "\"verify %s\"", arg);
1954 case CALLOUT_DEFER_OK: callout_defer_ok = TRUE; break;
1955 case CALLOUT_POSTMASTER: pm_mailfrom = US""; break;
1956 case CALLOUT_FULLPOSTMASTER: pm_mailfrom = US""; break;
1957 case CALLOUT_MAILFROM:
1958 if (!verify_header_sender)
1960 *log_msgptr = string_sprintf("\"mailfrom\" is allowed as a "
1961 "callout option only for verify=header_sender (detected in ACL "
1962 "condition \"%s\")", arg);
1965 se_mailfrom = string_copy(opt);
1967 case CALLOUT_POSTMASTER_MAILFROM: pm_mailfrom = string_copy(opt); break;
1968 case CALLOUT_MAXWAIT: callout_overall = period; break;
1969 case CALLOUT_CONNECT: callout_connect = period; break;
1970 case CALLOUT_TIME: callout = period; break;
1976 *log_msgptr = string_sprintf("'=' expected after \"callout\" in "
1977 "ACL condition \"%s\"", arg);
1983 /* Option not recognized */
1987 *log_msgptr = string_sprintf("unknown option \"%s\" in ACL "
1988 "condition \"verify %s\"", ss, arg);
1993 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster)) ==
1994 (vopt_callout_recipsender|vopt_callout_recippmaster))
1996 *log_msgptr = US"only one of use_sender and use_postmaster can be set "
1997 "for a recipient callout";
2001 /* Handle sender-in-header verification. Default the user message to the log
2002 message if giving out verification details. */
2004 if (verify_header_sender)
2007 rc = verify_check_header_address(user_msgptr, log_msgptr, callout,
2008 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, verify_options,
2012 *basic_errno = verrno;
2013 if (smtp_return_error_details)
2015 if (*user_msgptr == NULL && *log_msgptr != NULL)
2016 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
2017 if (rc == DEFER) acl_temp_details = TRUE;
2022 /* Handle a sender address. The default is to verify *the* sender address, but
2023 optionally a different address can be given, for special requirements. If the
2024 address is empty, we are dealing with a bounce message that has no sender, so
2025 we cannot do any checking. If the real sender address gets rewritten during
2026 verification (e.g. DNS widening), set the flag to stop it being rewritten again
2027 during message reception.
2029 A list of verified "sender" addresses is kept to try to avoid doing to much
2030 work repetitively when there are multiple recipients in a message and they all
2031 require sender verification. However, when callouts are involved, it gets too
2032 complicated because different recipients may require different callout options.
2033 Therefore, we always do a full sender verify when any kind of callout is
2034 specified. Caching elsewhere, for instance in the DNS resolver and in the
2035 callout handling, should ensure that this is not terribly inefficient. */
2037 else if (verify_sender_address != NULL)
2039 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster))
2042 *log_msgptr = US"use_sender or use_postmaster cannot be used for a "
2043 "sender verify callout";
2047 sender_vaddr = verify_checked_sender(verify_sender_address);
2048 if (sender_vaddr != NULL && /* Previously checked */
2049 callout <= 0) /* No callout needed this time */
2051 /* If the "routed" flag is set, it means that routing worked before, so
2052 this check can give OK (the saved return code value, if set, belongs to a
2053 callout that was done previously). If the "routed" flag is not set, routing
2054 must have failed, so we use the saved return code. */
2056 if (testflag(sender_vaddr, af_verify_routed)) rc = OK; else
2058 rc = sender_vaddr->special_action;
2059 *basic_errno = sender_vaddr->basic_errno;
2061 HDEBUG(D_acl) debug_printf("using cached sender verify result\n");
2064 /* Do a new verification, and cache the result. The cache is used to avoid
2065 verifying the sender multiple times for multiple RCPTs when callouts are not
2066 specified (see comments above).
2068 The cache is also used on failure to give details in response to the first
2069 RCPT that gets bounced for this reason. However, this can be suppressed by
2070 the no_details option, which sets the flag that says "this detail has already
2071 been sent". The cache normally contains just one address, but there may be
2072 more in esoteric circumstances. */
2077 uschar *save_address_data = deliver_address_data;
2079 sender_vaddr = deliver_make_addr(verify_sender_address, TRUE);
2080 if (no_details) setflag(sender_vaddr, af_sverify_told);
2081 if (verify_sender_address[0] != 0)
2083 /* If this is the real sender address, save the unrewritten version
2084 for use later in receive. Otherwise, set a flag so that rewriting the
2085 sender in verify_address() does not update sender_address. */
2087 if (verify_sender_address == sender_address)
2088 sender_address_unrewritten = sender_address;
2090 verify_options |= vopt_fake_sender;
2092 if (success_on_redirect)
2093 verify_options |= vopt_success_on_redirect;
2095 /* The recipient, qualify, and expn options are never set in
2098 rc = verify_address(sender_vaddr, NULL, verify_options, callout,
2099 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, &routed);
2101 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
2105 if (Ustrcmp(sender_vaddr->address, verify_sender_address) != 0)
2107 DEBUG(D_acl) debug_printf("sender %s verified ok as %s\n",
2108 verify_sender_address, sender_vaddr->address);
2112 DEBUG(D_acl) debug_printf("sender %s verified ok\n",
2113 verify_sender_address);
2116 else *basic_errno = sender_vaddr->basic_errno;
2118 else rc = OK; /* Null sender */
2120 /* Cache the result code */
2122 if (routed) setflag(sender_vaddr, af_verify_routed);
2123 if (callout > 0) setflag(sender_vaddr, af_verify_callout);
2124 sender_vaddr->special_action = rc;
2125 sender_vaddr->next = sender_verified_list;
2126 sender_verified_list = sender_vaddr;
2128 /* Restore the recipient address data, which might have been clobbered by
2129 the sender verification. */
2131 deliver_address_data = save_address_data;
2134 /* Put the sender address_data value into $sender_address_data */
2136 sender_address_data = sender_vaddr->p.address_data;
2139 /* A recipient address just gets a straightforward verify; again we must handle
2140 the DEFER overrides. */
2146 if (success_on_redirect)
2147 verify_options |= vopt_success_on_redirect;
2149 /* We must use a copy of the address for verification, because it might
2153 rc = verify_address(&addr2, NULL, verify_options|vopt_is_recipient, callout,
2154 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, NULL);
2155 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
2157 *basic_errno = addr2.basic_errno;
2158 *log_msgptr = addr2.message;
2159 *user_msgptr = (addr2.user_message != NULL)?
2160 addr2.user_message : addr2.message;
2162 /* Allow details for temporary error if the address is so flagged. */
2163 if (testflag((&addr2), af_pass_message)) acl_temp_details = TRUE;
2165 /* Make $address_data visible */
2166 deliver_address_data = addr2.p.address_data;
2169 /* We have a result from the relevant test. Handle defer overrides first. */
2171 if (rc == DEFER && (defer_ok ||
2172 (callout_defer_ok && *basic_errno == ERRNO_CALLOUTDEFER)))
2174 HDEBUG(D_acl) debug_printf("verify defer overridden by %s\n",
2175 defer_ok? "defer_ok" : "callout_defer_ok");
2179 /* If we've failed a sender, set up a recipient message, and point
2180 sender_verified_failed to the address item that actually failed. */
2182 if (rc != OK && verify_sender_address != NULL)
2186 *log_msgptr = *user_msgptr = US"Sender verify failed";
2188 else if (*basic_errno != ERRNO_CALLOUTDEFER)
2190 *log_msgptr = *user_msgptr = US"Could not complete sender verify";
2194 *log_msgptr = US"Could not complete sender verify callout";
2195 *user_msgptr = smtp_return_error_details? sender_vaddr->user_message :
2199 sender_verified_failed = sender_vaddr;
2202 /* Verifying an address messes up the values of $domain and $local_part,
2203 so reset them before returning if this is a RCPT ACL. */
2207 deliver_domain = addr->domain;
2208 deliver_localpart = addr->local_part;
2212 /* Syntax errors in the verify argument come here. */
2215 *log_msgptr = string_sprintf("expected \"sender[=address]\", \"recipient\", "
2216 "\"helo\", \"header_syntax\", \"header_sender\", \"header_names_ascii\" "
2217 "or \"reverse_host_lookup\" at start of ACL condition "
2218 "\"verify %s\"", arg);
2225 /*************************************************
2226 * Check argument for control= modifier *
2227 *************************************************/
2229 /* Called from acl_check_condition() below
2232 arg the argument string for control=
2233 pptr set to point to the terminating character
2234 where which ACL we are in
2235 log_msgptr for error messages
2237 Returns: CONTROL_xxx value
2241 decode_control(uschar *arg, uschar **pptr, int where, uschar **log_msgptr)
2246 for (d = controls_list;
2247 d < controls_list + sizeof(controls_list)/sizeof(control_def);
2250 len = Ustrlen(d->name);
2251 if (Ustrncmp(d->name, arg, len) == 0) break;
2254 if (d >= controls_list + sizeof(controls_list)/sizeof(control_def) ||
2255 (arg[len] != 0 && (!d->has_option || arg[len] != '/')))
2257 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
2258 return CONTROL_ERROR;
2268 /*************************************************
2269 * Return a ratelimit error *
2270 *************************************************/
2272 /* Called from acl_ratelimit() below
2275 log_msgptr for error messages
2276 format format string
2277 ... supplementary arguments
2278 ss ratelimit option name
2279 where ACL_WHERE_xxxx indicating which ACL this is
2285 ratelimit_error(uschar **log_msgptr, const char *format, ...)
2288 uschar buffer[STRING_SPRINTF_BUFFER_SIZE];
2289 va_start(ap, format);
2290 if (!string_vformat(buffer, sizeof(buffer), format, ap))
2291 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
2292 "string_sprintf expansion was longer than " SIZE_T_FMT, sizeof(buffer));
2294 *log_msgptr = string_sprintf(
2295 "error in arguments to \"ratelimit\" condition: %s", buffer);
2302 /*************************************************
2303 * Handle rate limiting *
2304 *************************************************/
2306 /* Called by acl_check_condition() below to calculate the result
2307 of the ACL ratelimit condition.
2309 Note that the return value might be slightly unexpected: if the
2310 sender's rate is above the limit then the result is OK. This is
2311 similar to the dnslists condition, and is so that you can write
2312 ACL clauses like: defer ratelimit = 15 / 1h
2315 arg the option string for ratelimit=
2316 where ACL_WHERE_xxxx indicating which ACL this is
2317 log_msgptr for error messages
2319 Returns: OK - Sender's rate is above limit
2320 FAIL - Sender's rate is below limit
2321 DEFER - Problem opening ratelimit database
2322 ERROR - Syntax error in options.
2326 acl_ratelimit(uschar *arg, int where, uschar **log_msgptr)
2328 double limit, period, count;
2331 uschar *unique = NULL;
2333 BOOL leaky = FALSE, strict = FALSE, readonly = FALSE;
2334 BOOL noupdate = FALSE, badacl = FALSE;
2335 int mode = RATE_PER_WHAT;
2337 tree_node **anchor, *t;
2338 open_db dbblock, *dbm;
2340 dbdata_ratelimit *dbd;
2341 dbdata_ratelimit_unique *dbdb;
2344 /* Parse the first two options and record their values in expansion
2345 variables. These variables allow the configuration to have informative
2346 error messages based on rate limits obtained from a table lookup. */
2348 /* First is the maximum number of messages per period / maximum burst
2349 size, which must be greater than or equal to zero. Zero is useful for
2350 rate measurement as opposed to rate limiting. */
2352 sender_rate_limit = string_nextinlist(&arg, &sep, NULL, 0);
2353 if (sender_rate_limit == NULL)
2357 limit = Ustrtod(sender_rate_limit, &ss);
2358 if (tolower(*ss) == 'k') { limit *= 1024.0; ss++; }
2359 else if (tolower(*ss) == 'm') { limit *= 1024.0*1024.0; ss++; }
2360 else if (tolower(*ss) == 'g') { limit *= 1024.0*1024.0*1024.0; ss++; }
2362 if (limit < 0.0 || *ss != '\0')
2363 return ratelimit_error(log_msgptr,
2364 "\"%s\" is not a positive number", sender_rate_limit);
2366 /* Second is the rate measurement period / exponential smoothing time
2367 constant. This must be strictly greater than zero, because zero leads to
2368 run-time division errors. */
2370 sender_rate_period = string_nextinlist(&arg, &sep, NULL, 0);
2371 if (sender_rate_period == NULL) period = -1.0;
2372 else period = readconf_readtime(sender_rate_period, 0, FALSE);
2374 return ratelimit_error(log_msgptr,
2375 "\"%s\" is not a time value", sender_rate_period);
2377 /* By default we are counting one of something, but the per_rcpt,
2378 per_byte, and count options can change this. */
2382 /* Parse the other options. */
2384 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2387 if (strcmpic(ss, US"leaky") == 0) leaky = TRUE;
2388 else if (strcmpic(ss, US"strict") == 0) strict = TRUE;
2389 else if (strcmpic(ss, US"noupdate") == 0) noupdate = TRUE;
2390 else if (strcmpic(ss, US"readonly") == 0) readonly = TRUE;
2391 else if (strcmpic(ss, US"per_cmd") == 0) RATE_SET(mode, PER_CMD);
2392 else if (strcmpic(ss, US"per_conn") == 0)
2394 RATE_SET(mode, PER_CONN);
2395 if (where == ACL_WHERE_NOTSMTP || where == ACL_WHERE_NOTSMTP_START)
2398 else if (strcmpic(ss, US"per_mail") == 0)
2400 RATE_SET(mode, PER_MAIL);
2401 if (where > ACL_WHERE_NOTSMTP) badacl = TRUE;
2403 else if (strcmpic(ss, US"per_rcpt") == 0)
2405 /* If we are running in the RCPT ACL, then we'll count the recipients
2406 one by one, but if we are running when we have accumulated the whole
2407 list then we'll add them all in one batch. */
2408 if (where == ACL_WHERE_RCPT)
2409 RATE_SET(mode, PER_RCPT);
2410 else if (where >= ACL_WHERE_PREDATA && where <= ACL_WHERE_NOTSMTP)
2411 RATE_SET(mode, PER_ALLRCPTS), count = (double)recipients_count;
2412 else if (where == ACL_WHERE_MAIL || where > ACL_WHERE_NOTSMTP)
2413 RATE_SET(mode, PER_RCPT), badacl = TRUE;
2415 else if (strcmpic(ss, US"per_byte") == 0)
2417 /* If we have not yet received the message data and there was no SIZE
2418 declaration on the MAIL comand, then it's safe to just use a value of
2419 zero and let the recorded rate decay as if nothing happened. */
2420 RATE_SET(mode, PER_MAIL);
2421 if (where > ACL_WHERE_NOTSMTP) badacl = TRUE;
2422 else count = message_size < 0 ? 0.0 : (double)message_size;
2424 else if (strcmpic(ss, US"per_addr") == 0)
2426 RATE_SET(mode, PER_RCPT);
2427 if (where != ACL_WHERE_RCPT) badacl = TRUE, unique = US"*";
2428 else unique = string_sprintf("%s@%s", deliver_localpart, deliver_domain);
2430 else if (strncmpic(ss, US"count=", 6) == 0)
2433 count = Ustrtod(ss+6, &e);
2434 if (count < 0.0 || *e != '\0')
2435 return ratelimit_error(log_msgptr,
2436 "\"%s\" is not a positive number", ss);
2438 else if (strncmpic(ss, US"unique=", 7) == 0)
2439 unique = string_copy(ss + 7);
2440 else if (key == NULL)
2441 key = string_copy(ss);
2443 key = string_sprintf("%s/%s", key, ss);
2446 /* Sanity check. When the badacl flag is set the update mode must either
2447 be readonly (which is the default if it is omitted) or, for backwards
2448 compatibility, a combination of noupdate and strict or leaky. */
2450 if (mode == RATE_PER_CLASH)
2451 return ratelimit_error(log_msgptr, "conflicting per_* options");
2452 if (leaky + strict + readonly > 1)
2453 return ratelimit_error(log_msgptr, "conflicting update modes");
2454 if (badacl && (leaky || strict) && !noupdate)
2455 return ratelimit_error(log_msgptr,
2456 "\"%s\" must not have /leaky or /strict option in %s ACL",
2457 ratelimit_option_string[mode], acl_wherenames[where]);
2459 /* Set the default values of any unset options. In readonly mode we
2460 perform the rate computation without any increment so that its value
2461 decays to eventually allow over-limit senders through. */
2463 if (noupdate) readonly = TRUE, leaky = strict = FALSE;
2464 if (badacl) readonly = TRUE;
2465 if (readonly) count = 0.0;
2466 if (!strict && !readonly) leaky = TRUE;
2467 if (mode == RATE_PER_WHAT) mode = RATE_PER_MAIL;
2469 /* Create the lookup key. If there is no explicit key, use sender_host_address.
2470 If there is no sender_host_address (e.g. -bs or acl_not_smtp) then we simply
2471 omit it. The smoothing constant (sender_rate_period) and the per_xxx options
2472 are added to the key because they alter the meaning of the stored data. */
2475 key = (sender_host_address == NULL)? US"" : sender_host_address;
2477 key = string_sprintf("%s/%s/%s%s",
2479 ratelimit_option_string[mode],
2480 unique == NULL ? "" : "unique/",
2484 debug_printf("ratelimit condition count=%.0f %.1f/%s\n", count, limit, key);
2486 /* See if we have already computed the rate by looking in the relevant tree.
2487 For per-connection rate limiting, store tree nodes and dbdata in the permanent
2488 pool so that they survive across resets. In readonly mode we only remember the
2489 result for the rest of this command in case a later command changes it. After
2490 this bit of logic the code is independent of the per_* mode. */
2492 old_pool = store_pool;
2495 anchor = &ratelimiters_cmd;
2498 anchor = &ratelimiters_conn;
2499 store_pool = POOL_PERM;
2503 case RATE_PER_ALLRCPTS:
2504 anchor = &ratelimiters_mail;
2509 anchor = &ratelimiters_cmd;
2512 anchor = NULL; /* silence an "unused" complaint */
2513 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
2514 "internal ACL error: unknown ratelimit mode %d", mode);
2518 t = tree_search(*anchor, key);
2522 /* The following few lines duplicate some of the code below. */
2523 rc = (dbd->rate < limit)? FAIL : OK;
2524 store_pool = old_pool;
2525 sender_rate = string_sprintf("%.1f", dbd->rate);
2527 debug_printf("ratelimit found pre-computed rate %s\n", sender_rate);
2531 /* We aren't using a pre-computed rate, so get a previously recorded rate
2532 from the database, which will be updated and written back if required. */
2534 dbm = dbfn_open(US"ratelimit", O_RDWR, &dbblock, TRUE);
2537 store_pool = old_pool;
2539 HDEBUG(D_acl) debug_printf("ratelimit database not available\n");
2540 *log_msgptr = US"ratelimit database not available";
2543 dbdb = dbfn_read_with_length(dbm, key, &dbdb_size);
2546 gettimeofday(&tv, NULL);
2550 /* Locate the basic ratelimit block inside the DB data. */
2551 HDEBUG(D_acl) debug_printf("ratelimit found key in database\n");
2554 /* Forget the old Bloom filter if it is too old, so that we count each
2555 repeating event once per period. We don't simply clear and re-use the old
2556 filter because we want its size to change if the limit changes. Note that
2557 we keep the dbd pointer for copying the rate into the new data block. */
2559 if(unique != NULL && tv.tv_sec > dbdb->bloom_epoch + period)
2561 HDEBUG(D_acl) debug_printf("ratelimit discarding old Bloom filter\n");
2567 if(unique != NULL && dbdb_size < sizeof(*dbdb))
2569 HDEBUG(D_acl) debug_printf("ratelimit discarding undersize Bloom filter\n");
2574 /* Allocate a new data block if the database lookup failed
2575 or the Bloom filter passed its age limit. */
2581 /* No Bloom filter. This basic ratelimit block is initialized below. */
2582 HDEBUG(D_acl) debug_printf("ratelimit creating new rate data block\n");
2583 dbdb_size = sizeof(*dbd);
2584 dbdb = store_get(dbdb_size);
2589 HDEBUG(D_acl) debug_printf("ratelimit creating new Bloom filter\n");
2591 /* See the long comment below for an explanation of the magic number 2.
2592 The filter has a minimum size in case the rate limit is very small;
2593 this is determined by the definition of dbdata_ratelimit_unique. */
2595 extra = (int)limit * 2 - sizeof(dbdb->bloom);
2596 if (extra < 0) extra = 0;
2597 dbdb_size = sizeof(*dbdb) + extra;
2598 dbdb = store_get(dbdb_size);
2599 dbdb->bloom_epoch = tv.tv_sec;
2600 dbdb->bloom_size = sizeof(dbdb->bloom) + extra;
2601 memset(dbdb->bloom, 0, dbdb->bloom_size);
2603 /* Preserve any basic ratelimit data (which is our longer-term memory)
2604 by copying it from the discarded block. */
2614 /* If we are counting unique events, find out if this event is new or not.
2615 If the client repeats the event during the current period then it should be
2616 counted. We skip this code in readonly mode for efficiency, because any
2617 changes to the filter will be discarded and because count is already set to
2620 if (unique != NULL && !readonly)
2622 /* We identify unique events using a Bloom filter. (You can find my
2623 notes on Bloom filters at http://fanf.livejournal.com/81696.html)
2624 With the per_addr option, an "event" is a recipient address, though the
2625 user can use the unique option to define their own events. We only count
2626 an event if we have not seen it before.
2628 We size the filter according to the rate limit, which (in leaky mode)
2629 is the limit on the population of the filter. We allow 16 bits of space
2630 per entry (see the construction code above) and we set (up to) 8 of them
2631 when inserting an element (see the loop below). The probability of a false
2632 positive (an event we have not seen before but which we fail to count) is
2636 allzero = exp(-numhash * pop / size)
2637 = exp(-0.5 * pop / limit)
2638 fpr = pow(1 - allzero, numhash)
2640 For senders at the limit the fpr is 0.06% or 1 in 1700
2641 and for senders at half the limit it is 0.0006% or 1 in 170000
2643 In strict mode the Bloom filter can fill up beyond the normal limit, in
2644 which case the false positive rate will rise. This means that the
2645 measured rate for very fast senders can bogusly drop off after a while.
2647 At twice the limit, the fpr is 2.5% or 1 in 40
2648 At four times the limit, it is 31% or 1 in 3.2
2650 It takes ln(pop/limit) periods for an over-limit burst of pop events to
2651 decay below the limit, and if this is more than one then the Bloom filter
2652 will be discarded before the decay gets that far. The false positive rate
2653 at this threshold is 9.3% or 1 in 10.7. */
2656 unsigned n, hash, hinc;
2660 /* Instead of using eight independent hash values, we combine two values
2661 using the formula h1 + n * h2. This does not harm the Bloom filter's
2662 performance, and means the amount of hash we need is independent of the
2663 number of bits we set in the filter. */
2665 md5_start(&md5info);
2666 md5_end(&md5info, unique, Ustrlen(unique), md5sum);
2667 hash = md5sum[0] | md5sum[1] << 8 | md5sum[2] << 16 | md5sum[3] << 24;
2668 hinc = md5sum[4] | md5sum[5] << 8 | md5sum[6] << 16 | md5sum[7] << 24;
2670 /* Scan the bits corresponding to this event. A zero bit means we have
2671 not seen it before. Ensure all bits are set to record this event. */
2673 HDEBUG(D_acl) debug_printf("ratelimit checking uniqueness of %s\n", unique);
2676 for (n = 0; n < 8; n++, hash += hinc)
2678 int bit = 1 << (hash % 8);
2679 int byte = (hash / 8) % dbdb->bloom_size;
2680 if ((dbdb->bloom[byte] & bit) == 0)
2682 dbdb->bloom[byte] |= bit;
2687 /* If this event has occurred before, do not count it. */
2691 HDEBUG(D_acl) debug_printf("ratelimit event found in Bloom filter\n");
2695 HDEBUG(D_acl) debug_printf("ratelimit event added to Bloom filter\n");
2698 /* If there was no previous ratelimit data block for this key, initialize
2699 the new one, otherwise update the block from the database. The initial rate
2700 is what would be computed by the code below for an infinite interval. */
2704 HDEBUG(D_acl) debug_printf("ratelimit initializing new key's rate data\n");
2706 dbd->time_stamp = tv.tv_sec;
2707 dbd->time_usec = tv.tv_usec;
2712 /* The smoothed rate is computed using an exponentially weighted moving
2713 average adjusted for variable sampling intervals. The standard EWMA for
2714 a fixed sampling interval is: f'(t) = (1 - a) * f(t) + a * f'(t - 1)
2715 where f() is the measured value and f'() is the smoothed value.
2717 Old data decays out of the smoothed value exponentially, such that data n
2718 samples old is multiplied by a^n. The exponential decay time constant p
2719 is defined such that data p samples old is multiplied by 1/e, which means
2720 that a = exp(-1/p). We can maintain the same time constant for a variable
2721 sampling interval i by using a = exp(-i/p).
2723 The rate we are measuring is messages per period, suitable for directly
2724 comparing with the limit. The average rate between now and the previous
2725 message is period / interval, which we feed into the EWMA as the sample.
2727 It turns out that the number of messages required for the smoothed rate
2728 to reach the limit when they are sent in a burst is equal to the limit.
2729 This can be seen by analysing the value of the smoothed rate after N
2730 messages sent at even intervals. Let k = (1 - a) * p/i
2732 rate_1 = (1 - a) * p/i + a * rate_0
2734 rate_2 = k + a * rate_1
2735 = k + a * k + a^2 * rate_0
2736 rate_3 = k + a * k + a^2 * k + a^3 * rate_0
2737 rate_N = rate_0 * a^N + k * SUM(x=0..N-1)(a^x)
2738 = rate_0 * a^N + k * (1 - a^N) / (1 - a)
2739 = rate_0 * a^N + p/i * (1 - a^N)
2741 When N is large, a^N -> 0 so rate_N -> p/i as desired.
2743 rate_N = p/i + (rate_0 - p/i) * a^N
2744 a^N = (rate_N - p/i) / (rate_0 - p/i)
2745 N * -i/p = log((rate_N - p/i) / (rate_0 - p/i))
2746 N = p/i * log((rate_0 - p/i) / (rate_N - p/i))
2748 Numerical analysis of the above equation, setting the computed rate to
2749 increase from rate_0 = 0 to rate_N = limit, shows that for large sending
2750 rates, p/i, the number of messages N = limit. So limit serves as both the
2751 maximum rate measured in messages per period, and the maximum number of
2752 messages that can be sent in a fast burst. */
2754 double this_time = (double)tv.tv_sec
2755 + (double)tv.tv_usec / 1000000.0;
2756 double prev_time = (double)dbd->time_stamp
2757 + (double)dbd->time_usec / 1000000.0;
2759 /* We must avoid division by zero, and deal gracefully with the clock going
2760 backwards. If we blunder ahead when time is in reverse then the computed
2761 rate will be bogus. To be safe we clamp interval to a very small number. */
2763 double interval = this_time - prev_time <= 0.0 ? 1e-9
2764 : this_time - prev_time;
2766 double i_over_p = interval / period;
2767 double a = exp(-i_over_p);
2769 /* Combine the instantaneous rate (period / interval) with the previous rate
2770 using the smoothing factor a. In order to measure sized events, multiply the
2771 instantaneous rate by the count of bytes or recipients etc. */
2773 dbd->time_stamp = tv.tv_sec;
2774 dbd->time_usec = tv.tv_usec;
2775 dbd->rate = (1 - a) * count / i_over_p + a * dbd->rate;
2777 /* When events are very widely spaced the computed rate tends towards zero.
2778 Although this is accurate it turns out not to be useful for our purposes,
2779 especially when the first event after a long silence is the start of a spam
2780 run. A more useful model is that the rate for an isolated event should be the
2781 size of the event per the period size, ignoring the lack of events outside
2782 the current period and regardless of where the event falls in the period. So,
2783 if the interval was so long that the calculated rate is unhelpfully small, we
2784 re-intialize the rate. In the absence of higher-rate bursts, the condition
2785 below is true if the interval is greater than the period. */
2787 if (dbd->rate < count) dbd->rate = count;
2790 /* Clients sending at the limit are considered to be over the limit.
2791 This matters for edge cases such as a limit of zero, when the client
2792 should be completely blocked. */
2794 rc = (dbd->rate < limit)? FAIL : OK;
2796 /* Update the state if the rate is low or if we are being strict. If we
2797 are in leaky mode and the sender's rate is too high, we do not update
2798 the recorded rate in order to avoid an over-aggressive sender's retry
2799 rate preventing them from getting any email through. If readonly is set,
2800 neither leaky nor strict are set, so we do not do any updates. */
2802 if ((rc == FAIL && leaky) || strict)
2804 dbfn_write(dbm, key, dbdb, dbdb_size);
2805 HDEBUG(D_acl) debug_printf("ratelimit db updated\n");
2809 HDEBUG(D_acl) debug_printf("ratelimit db not updated: %s\n",
2810 readonly? "readonly mode" : "over the limit, but leaky");
2815 /* Store the result in the tree for future reference. */
2817 t = store_get(sizeof(tree_node) + Ustrlen(key));
2819 Ustrcpy(t->name, key);
2820 (void)tree_insertnode(anchor, t);
2822 /* We create the formatted version of the sender's rate very late in
2823 order to ensure that it is done using the correct storage pool. */
2825 store_pool = old_pool;
2826 sender_rate = string_sprintf("%.1f", dbd->rate);
2829 debug_printf("ratelimit computed rate %s\n", sender_rate);
2836 /*************************************************
2837 * The udpsend ACL modifier *
2838 *************************************************/
2840 /* Called by acl_check_condition() below.
2843 arg the option string for udpsend=
2844 log_msgptr for error messages
2846 Returns: OK - Completed.
2847 DEFER - Problem with DNS lookup.
2848 ERROR - Syntax error in options.
2852 acl_udpsend(uschar *arg, uschar **log_msgptr)
2864 hostname = string_nextinlist(&arg, &sep, NULL, 0);
2865 portstr = string_nextinlist(&arg, &sep, NULL, 0);
2867 if (hostname == NULL)
2869 *log_msgptr = US"missing destination host in \"udpsend\" modifier";
2872 if (portstr == NULL)
2874 *log_msgptr = US"missing destination port in \"udpsend\" modifier";
2879 *log_msgptr = US"missing datagram payload in \"udpsend\" modifier";
2882 portnum = Ustrtol(portstr, &portend, 10);
2883 if (*portend != '\0')
2885 *log_msgptr = US"bad destination port in \"udpsend\" modifier";
2889 /* Make a single-item host list. */
2890 h = store_get(sizeof(host_item));
2891 memset(h, 0, sizeof(host_item));
2896 if (string_is_ip_address(hostname, NULL))
2897 h->address = hostname, r = HOST_FOUND;
2899 r = host_find_byname(h, NULL, 0, NULL, FALSE);
2900 if (r == HOST_FIND_FAILED || r == HOST_FIND_AGAIN)
2902 *log_msgptr = US"DNS lookup failed in \"udpsend\" modifier";
2907 debug_printf("udpsend [%s]:%d %s\n", h->address, portnum, arg);
2909 r = s = ip_connectedsocket(SOCK_DGRAM, h->address, portnum, portnum,
2911 if (r < 0) goto defer;
2913 r = send(s, arg, len, 0);
2916 errstr = US strerror(errno);
2924 string_sprintf("\"udpsend\" truncated from %d to %d octets", len, r);
2929 debug_printf("udpsend %d bytes\n", r);
2934 *log_msgptr = string_sprintf("\"udpsend\" failed: %s", errstr);
2940 /*************************************************
2941 * Handle conditions/modifiers on an ACL item *
2942 *************************************************/
2944 /* Called from acl_check() below.
2948 cb ACL condition block - if NULL, result is OK
2949 where where called from
2950 addr the address being checked for RCPT, or NULL
2951 level the nesting level
2952 epp pointer to pass back TRUE if "endpass" encountered
2953 (applies only to "accept" and "discard")
2954 user_msgptr user message pointer
2955 log_msgptr log message pointer
2956 basic_errno pointer to where to put verify error
2958 Returns: OK - all conditions are met
2959 DISCARD - an "acl" condition returned DISCARD - only allowed
2960 for "accept" or "discard" verbs
2961 FAIL - at least one condition fails
2962 FAIL_DROP - an "acl" condition returned FAIL_DROP
2963 DEFER - can't tell at the moment (typically, lookup defer,
2964 but can be temporary callout problem)
2965 ERROR - ERROR from nested ACL or expansion failure or other
2970 acl_check_condition(int verb, acl_condition_block *cb, int where,
2971 address_item *addr, int level, BOOL *epp, uschar **user_msgptr,
2972 uschar **log_msgptr, int *basic_errno)
2974 uschar *user_message = NULL;
2975 uschar *log_message = NULL;
2976 uschar *debug_tag = NULL;
2977 uschar *debug_opts = NULL;
2980 #ifdef WITH_CONTENT_SCAN
2984 for (; cb != NULL; cb = cb->next)
2989 /* The message and log_message items set up messages to be used in
2990 case of rejection. They are expanded later. */
2992 if (cb->type == ACLC_MESSAGE)
2994 user_message = cb->arg;
2998 if (cb->type == ACLC_LOG_MESSAGE)
3000 log_message = cb->arg;
3004 /* The endpass "condition" just sets a flag to show it occurred. This is
3005 checked at compile time to be on an "accept" or "discard" item. */
3007 if (cb->type == ACLC_ENDPASS)
3013 /* For other conditions and modifiers, the argument is expanded now for some
3014 of them, but not for all, because expansion happens down in some lower level
3015 checking functions in some cases. */
3017 if (cond_expand_at_top[cb->type])
3019 arg = expand_string(cb->arg);
3022 if (expand_string_forcedfail) continue;
3023 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s",
3024 cb->arg, expand_string_message);
3025 return search_find_defer? DEFER : ERROR;
3030 /* Show condition, and expanded condition if it's different */
3035 debug_printf("check %s%s %n",
3036 (!cond_modifiers[cb->type] && cb->u.negated)? "!":"",
3037 conditions[cb->type], &lhswidth);
3039 if (cb->type == ACLC_SET)
3041 debug_printf("acl_%s ", cb->u.varname);
3042 lhswidth += 5 + Ustrlen(cb->u.varname);
3045 debug_printf("= %s\n", cb->arg);
3048 debug_printf("%.*s= %s\n", lhswidth,
3052 /* Check that this condition makes sense at this time */
3054 if ((cond_forbids[cb->type] & (1 << where)) != 0)
3056 *log_msgptr = string_sprintf("cannot %s %s condition in %s ACL",
3057 cond_modifiers[cb->type]? "use" : "test",
3058 conditions[cb->type], acl_wherenames[where]);
3062 /* Run the appropriate test for each condition, or take the appropriate
3063 action for the remaining modifiers. */
3067 case ACLC_ADD_HEADER:
3071 /* A nested ACL that returns "discard" makes sense only for an "accept" or
3075 rc = acl_check_wargs(where, addr, arg, level+1, user_msgptr, log_msgptr);
3076 if (rc == DISCARD && verb != ACL_ACCEPT && verb != ACL_DISCARD)
3078 *log_msgptr = string_sprintf("nested ACL returned \"discard\" for "
3079 "\"%s\" command (only allowed with \"accept\" or \"discard\")",
3085 case ACLC_AUTHENTICATED:
3086 rc = (sender_host_authenticated == NULL)? FAIL :
3087 match_isinlist(sender_host_authenticated, &arg, 0, NULL, NULL, MCL_STRING,
3091 #ifdef EXPERIMENTAL_BRIGHTMAIL
3092 case ACLC_BMI_OPTIN:
3094 int old_pool = store_pool;
3095 store_pool = POOL_PERM;
3096 bmi_current_optin = string_copy(arg);
3097 store_pool = old_pool;
3102 case ACLC_CONDITION:
3103 /* The true/false parsing here should be kept in sync with that used in
3104 expand.c when dealing with ECOND_BOOL so that we don't have too many
3105 different definitions of what can be a boolean. */
3106 if (Ustrspn(arg, "0123456789") == Ustrlen(arg)) /* Digits, or empty */
3107 rc = (Uatoi(arg) == 0)? FAIL : OK;
3109 rc = (strcmpic(arg, US"no") == 0 ||
3110 strcmpic(arg, US"false") == 0)? FAIL :
3111 (strcmpic(arg, US"yes") == 0 ||
3112 strcmpic(arg, US"true") == 0)? OK : DEFER;
3114 *log_msgptr = string_sprintf("invalid \"condition\" value \"%s\"", arg);
3117 case ACLC_CONTINUE: /* Always succeeds */
3121 control_type = decode_control(arg, &p, where, log_msgptr);
3123 /* Check if this control makes sense at this time */
3125 if ((control_forbids[control_type] & (1 << where)) != 0)
3127 *log_msgptr = string_sprintf("cannot use \"control=%s\" in %s ACL",
3128 controls[control_type], acl_wherenames[where]);
3132 switch(control_type)
3134 case CONTROL_AUTH_UNADVERTISED:
3135 allow_auth_unadvertised = TRUE;
3138 #ifdef EXPERIMENTAL_BRIGHTMAIL
3139 case CONTROL_BMI_RUN:
3144 #ifndef DISABLE_DKIM
3145 case CONTROL_DKIM_VERIFY:
3146 dkim_disable_verify = TRUE;
3147 #ifdef EXPERIMENTAL_DMARC
3148 /* Since DKIM was blocked, skip DMARC too */
3149 dmarc_disable_verify = TRUE;
3150 dmarc_enable_forensic = FALSE;
3155 #ifdef EXPERIMENTAL_DMARC
3156 case CONTROL_DMARC_VERIFY:
3157 dmarc_disable_verify = TRUE;
3160 case CONTROL_DMARC_FORENSIC:
3161 dmarc_enable_forensic = TRUE;
3168 int fd, af, level, optname, value;
3169 /* If we are acting on stdin, the setsockopt may fail if stdin is not
3170 a socket; we can accept that, we'll just debug-log failures anyway. */
3171 fd = fileno(smtp_in);
3172 af = ip_get_address_family(fd);
3176 debug_printf("smtp input is probably not a socket [%s], not setting DSCP\n",
3180 if (dscp_lookup(p+1, af, &level, &optname, &value))
3182 if (setsockopt(fd, level, optname, &value, sizeof(value)) < 0)
3184 HDEBUG(D_acl) debug_printf("failed to set input DSCP[%s]: %s\n",
3185 p+1, strerror(errno));
3189 HDEBUG(D_acl) debug_printf("set input DSCP to \"%s\"\n", p+1);
3194 *log_msgptr = string_sprintf("unrecognised DSCP value in \"control=%s\"", arg);
3200 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3208 case CONTROL_CASEFUL_LOCAL_PART:
3209 deliver_localpart = addr->cc_local_part;
3212 case CONTROL_CASELOWER_LOCAL_PART:
3213 deliver_localpart = addr->lc_local_part;
3216 case CONTROL_ENFORCE_SYNC:
3217 smtp_enforce_sync = TRUE;
3220 case CONTROL_NO_ENFORCE_SYNC:
3221 smtp_enforce_sync = FALSE;
3224 #ifdef WITH_CONTENT_SCAN
3225 case CONTROL_NO_MBOX_UNSPOOL:
3226 no_mbox_unspool = TRUE;
3230 case CONTROL_NO_MULTILINE:
3231 no_multiline_responses = TRUE;
3234 case CONTROL_NO_PIPELINING:
3235 pipelining_enable = FALSE;
3238 case CONTROL_NO_DELAY_FLUSH:
3239 disable_delay_flush = TRUE;
3242 case CONTROL_NO_CALLOUT_FLUSH:
3243 disable_callout_flush = TRUE;
3246 case CONTROL_FAKEDEFER:
3247 case CONTROL_FAKEREJECT:
3248 fake_response = (control_type == CONTROL_FAKEDEFER) ? DEFER : FAIL;
3252 while (*pp != 0) pp++;
3253 fake_response_text = expand_string(string_copyn(p+1, pp-p-1));
3258 /* Explicitly reset to default string */
3259 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).";
3263 case CONTROL_FREEZE:
3264 deliver_freeze = TRUE;
3265 deliver_frozen_at = time(NULL);
3266 freeze_tell = freeze_tell_config; /* Reset to configured value */
3267 if (Ustrncmp(p, "/no_tell", 8) == 0)
3274 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3279 case CONTROL_QUEUE_ONLY:
3280 queue_only_policy = TRUE;
3283 case CONTROL_SUBMISSION:
3284 originator_name = US"";
3285 submission_mode = TRUE;
3288 if (Ustrncmp(p, "/sender_retain", 14) == 0)
3291 active_local_sender_retain = TRUE;
3292 active_local_from_check = FALSE;
3294 else if (Ustrncmp(p, "/domain=", 8) == 0)
3297 while (*pp != 0 && *pp != '/') pp++;
3298 submission_domain = string_copyn(p+8, pp-p-8);
3301 /* The name= option must be last, because it swallows the rest of
3303 else if (Ustrncmp(p, "/name=", 6) == 0)
3306 while (*pp != 0) pp++;
3307 submission_name = string_copy(parse_fix_phrase(p+6, pp-p-6,
3308 big_buffer, big_buffer_size));
3315 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3323 if (Ustrncmp(p, "/tag=", 5) == 0)
3326 while (*pp != '\0' && *pp != '/') pp++;
3327 debug_tag = string_copyn(p+5, pp-p-5);
3330 else if (Ustrncmp(p, "/opts=", 6) == 0)
3333 while (*pp != '\0' && *pp != '/') pp++;
3334 debug_opts = string_copyn(p+6, pp-p-6);
3338 debug_logging_activate(debug_tag, debug_opts);
3341 case CONTROL_SUPPRESS_LOCAL_FIXUPS:
3342 suppress_local_fixups = TRUE;
3345 case CONTROL_CUTTHROUGH_DELIVERY:
3348 *log_msgptr = string_sprintf("\"control=%s\" on frozen item", arg);
3351 if (queue_only_policy)
3353 *log_msgptr = string_sprintf("\"control=%s\" on queue-only item", arg);
3356 cutthrough_delivery = TRUE;
3361 #ifdef EXPERIMENTAL_DCC
3364 /* Seperate the regular expression and any optional parameters. */
3365 uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size);
3366 /* Run the dcc backend. */
3367 rc = dcc_process(&ss);
3368 /* Modify return code based upon the existance of options. */
3369 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
3371 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
3373 /* FAIL so that the message is passed to the next ACL */
3381 #ifdef WITH_CONTENT_SCAN
3383 rc = mime_decode(&arg);
3389 int delay = readconf_readtime(arg, 0, FALSE);
3392 *log_msgptr = string_sprintf("syntax error in argument for \"delay\" "
3393 "modifier: \"%s\" is not a time value", arg);
3398 HDEBUG(D_acl) debug_printf("delay modifier requests %d-second delay\n",
3403 debug_printf("delay skipped in -bh checking mode\n");
3406 /* It appears to be impossible to detect that a TCP/IP connection has
3407 gone away without reading from it. This means that we cannot shorten
3408 the delay below if the client goes away, because we cannot discover
3409 that the client has closed its end of the connection. (The connection
3410 is actually in a half-closed state, waiting for the server to close its
3411 end.) It would be nice to be able to detect this state, so that the
3412 Exim process is not held up unnecessarily. However, it seems that we
3413 can't. The poll() function does not do the right thing, and in any case
3414 it is not always available.
3416 NOTE 1: If ever this state of affairs changes, remember that we may be
3417 dealing with stdin/stdout here, in addition to TCP/IP connections.
3418 Also, delays may be specified for non-SMTP input, where smtp_out and
3419 smtp_in will be NULL. Whatever is done must work in all cases.
3421 NOTE 2: The added feature of flushing the output before a delay must
3422 apply only to SMTP input. Hence the test for smtp_out being non-NULL.
3427 if (smtp_out != NULL && !disable_delay_flush) mac_smtp_fflush();
3428 while (delay > 0) delay = sleep(delay);
3434 #ifdef WITH_OLD_DEMIME
3440 #ifndef DISABLE_DKIM
3441 case ACLC_DKIM_SIGNER:
3442 if (dkim_cur_signer != NULL)
3443 rc = match_isinlist(dkim_cur_signer,
3444 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
3449 case ACLC_DKIM_STATUS:
3450 rc = match_isinlist(dkim_exim_expand_query(DKIM_VERIFY_STATUS),
3451 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
3455 #ifdef EXPERIMENTAL_DMARC
3456 case ACLC_DMARC_STATUS:
3457 if (!dmarc_has_been_checked)
3459 dmarc_has_been_checked = TRUE;
3460 /* used long way of dmarc_exim_expand_query() in case we need more
3461 * view into the process in the future. */
3462 rc = match_isinlist(dmarc_exim_expand_query(DMARC_VERIFY_STATUS),
3463 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
3468 rc = verify_check_dnsbl(&arg);
3472 rc = match_isinlist(addr->domain, &arg, 0, &domainlist_anchor,
3473 addr->domain_cache, MCL_DOMAIN, TRUE, &deliver_domain_data);
3476 /* The value in tls_cipher is the full cipher name, for example,
3477 TLSv1:DES-CBC3-SHA:168, whereas the values to test for are just the
3478 cipher names such as DES-CBC3-SHA. But program defensively. We don't know
3479 what may in practice come out of the SSL library - which at the time of
3480 writing is poorly documented. */
3482 case ACLC_ENCRYPTED:
3483 if (tls_in.cipher == NULL) rc = FAIL; else
3485 uschar *endcipher = NULL;
3486 uschar *cipher = Ustrchr(tls_in.cipher, ':');
3487 if (cipher == NULL) cipher = tls_in.cipher; else
3489 endcipher = Ustrchr(++cipher, ':');
3490 if (endcipher != NULL) *endcipher = 0;
3492 rc = match_isinlist(cipher, &arg, 0, NULL, NULL, MCL_STRING, TRUE, NULL);
3493 if (endcipher != NULL) *endcipher = ':';
3497 /* Use verify_check_this_host() instead of verify_check_host() so that
3498 we can pass over &host_data to catch any looked up data. Once it has been
3499 set, it retains its value so that it's still there if another ACL verb
3500 comes through here and uses the cache. However, we must put it into
3501 permanent store in case it is also expected to be used in a subsequent
3502 message in the same SMTP connection. */
3505 rc = verify_check_this_host(&arg, sender_host_cache, NULL,
3506 (sender_host_address == NULL)? US"" : sender_host_address, &host_data);
3507 if (host_data != NULL) host_data = string_copy_malloc(host_data);
3510 case ACLC_LOCAL_PARTS:
3511 rc = match_isinlist(addr->cc_local_part, &arg, 0,
3512 &localpartlist_anchor, addr->localpart_cache, MCL_LOCALPART, TRUE,
3513 &deliver_localpart_data);
3516 case ACLC_LOG_REJECT_TARGET:
3522 while ((ss = string_nextinlist(&s, &sep, big_buffer, big_buffer_size))
3525 if (Ustrcmp(ss, "main") == 0) logbits |= LOG_MAIN;
3526 else if (Ustrcmp(ss, "panic") == 0) logbits |= LOG_PANIC;
3527 else if (Ustrcmp(ss, "reject") == 0) logbits |= LOG_REJECT;
3530 logbits |= LOG_MAIN|LOG_REJECT;
3531 log_write(0, LOG_MAIN|LOG_PANIC, "unknown log name \"%s\" in "
3532 "\"log_reject_target\" in %s ACL", ss, acl_wherenames[where]);
3535 log_reject_target = logbits;
3548 if (Ustrncmp(s, "main", 4) == 0)
3549 { logbits |= LOG_MAIN; s += 4; }
3550 else if (Ustrncmp(s, "panic", 5) == 0)
3551 { logbits |= LOG_PANIC; s += 5; }
3552 else if (Ustrncmp(s, "reject", 6) == 0)
3553 { logbits |= LOG_REJECT; s += 6; }
3556 logbits = LOG_MAIN|LOG_PANIC;
3557 s = string_sprintf(":unknown log name in \"%s\" in "
3558 "\"logwrite\" in %s ACL", arg, acl_wherenames[where]);
3564 while (isspace(*s)) s++;
3567 if (logbits == 0) logbits = LOG_MAIN;
3568 log_write(0, logbits, "%s", string_printing(s));
3572 #ifdef WITH_CONTENT_SCAN
3575 /* Separate the regular expression and any optional parameters. */
3576 uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size);
3577 /* Run the malware backend. */
3579 /* Modify return code based upon the existance of options. */
3580 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
3582 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
3584 /* FAIL so that the message is passed to the next ACL */
3591 case ACLC_MIME_REGEX:
3592 rc = mime_regex(&arg);
3596 case ACLC_RATELIMIT:
3597 rc = acl_ratelimit(arg, where, log_msgptr);
3600 case ACLC_RECIPIENTS:
3601 rc = match_address_list(addr->address, TRUE, TRUE, &arg, NULL, -1, 0,
3605 #ifdef WITH_CONTENT_SCAN
3611 case ACLC_REMOVE_HEADER:
3612 setup_remove_header(arg);
3615 case ACLC_SENDER_DOMAINS:
3618 sdomain = Ustrrchr(sender_address, '@');
3619 sdomain = (sdomain == NULL)? US"" : sdomain + 1;
3620 rc = match_isinlist(sdomain, &arg, 0, &domainlist_anchor,
3621 sender_domain_cache, MCL_DOMAIN, TRUE, NULL);
3626 rc = match_address_list(sender_address, TRUE, TRUE, &arg,
3627 sender_address_cache, -1, 0, &sender_data);
3630 /* Connection variables must persist forever */
3634 int old_pool = store_pool;
3635 if (cb->u.varname[0] == 'c') store_pool = POOL_PERM;
3636 acl_var_create(cb->u.varname)->data.ptr = string_copy(arg);
3637 store_pool = old_pool;
3641 #ifdef WITH_CONTENT_SCAN
3644 /* Seperate the regular expression and any optional parameters. */
3645 uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size);
3646 /* Run the spam backend. */
3648 /* Modify return code based upon the existance of options. */
3649 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
3651 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
3653 /* FAIL so that the message is passed to the next ACL */
3661 #ifdef EXPERIMENTAL_SPF
3663 rc = spf_process(&arg, sender_address, SPF_PROCESS_NORMAL);
3665 case ACLC_SPF_GUESS:
3666 rc = spf_process(&arg, sender_address, SPF_PROCESS_GUESS);
3671 rc = acl_udpsend(arg, log_msgptr);
3674 /* If the verb is WARN, discard any user message from verification, because
3675 such messages are SMTP responses, not header additions. The latter come
3676 only from explicit "message" modifiers. However, put the user message into
3677 $acl_verify_message so it can be used in subsequent conditions or modifiers
3678 (until something changes it). */
3681 rc = acl_verify(where, addr, arg, user_msgptr, log_msgptr, basic_errno);
3682 acl_verify_message = *user_msgptr;
3683 if (verb == ACL_WARN) *user_msgptr = NULL;
3687 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown "
3688 "condition %d", cb->type);
3692 /* If a condition was negated, invert OK/FAIL. */
3694 if (!cond_modifiers[cb->type] && cb->u.negated)
3696 if (rc == OK) rc = FAIL;
3697 else if (rc == FAIL || rc == FAIL_DROP) rc = OK;
3700 if (rc != OK) break; /* Conditions loop */
3704 /* If the result is the one for which "message" and/or "log_message" are used,
3705 handle the values of these modifiers. If there isn't a log message set, we make
3706 it the same as the user message.
3708 "message" is a user message that will be included in an SMTP response. Unless
3709 it is empty, it overrides any previously set user message.
3711 "log_message" is a non-user message, and it adds to any existing non-user
3712 message that is already set.
3714 Most verbs have but a single return for which the messages are relevant, but
3715 for "discard", it's useful to have the log message both when it succeeds and
3716 when it fails. For "accept", the message is used in the OK case if there is no
3717 "endpass", but (for backwards compatibility) in the FAIL case if "endpass" is
3720 if (*epp && rc == OK) user_message = NULL;
3722 if (((1<<rc) & msgcond[verb]) != 0)
3725 uschar *old_user_msgptr = *user_msgptr;
3726 uschar *old_log_msgptr = (*log_msgptr != NULL)? *log_msgptr : old_user_msgptr;
3728 /* If the verb is "warn", messages generated by conditions (verification or
3729 nested ACLs) are always discarded. This also happens for acceptance verbs
3730 when they actually do accept. Only messages specified at this level are used.
3731 However, the value of an existing message is available in $acl_verify_message
3732 during expansions. */
3734 if (verb == ACL_WARN ||
3735 (rc == OK && (verb == ACL_ACCEPT || verb == ACL_DISCARD)))
3736 *log_msgptr = *user_msgptr = NULL;
3738 if (user_message != NULL)
3740 acl_verify_message = old_user_msgptr;
3741 expmessage = expand_string(user_message);
3742 if (expmessage == NULL)
3744 if (!expand_string_forcedfail)
3745 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
3746 user_message, expand_string_message);
3748 else if (expmessage[0] != 0) *user_msgptr = expmessage;
3751 if (log_message != NULL)
3753 acl_verify_message = old_log_msgptr;
3754 expmessage = expand_string(log_message);
3755 if (expmessage == NULL)
3757 if (!expand_string_forcedfail)
3758 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
3759 log_message, expand_string_message);
3761 else if (expmessage[0] != 0)
3763 *log_msgptr = (*log_msgptr == NULL)? expmessage :
3764 string_sprintf("%s: %s", expmessage, *log_msgptr);
3768 /* If no log message, default it to the user message */
3770 if (*log_msgptr == NULL) *log_msgptr = *user_msgptr;
3773 acl_verify_message = NULL;
3781 /*************************************************
3782 * Get line from a literal ACL *
3783 *************************************************/
3785 /* This function is passed to acl_read() in order to extract individual lines
3786 of a literal ACL, which we access via static pointers. We can destroy the
3787 contents because this is called only once (the compiled ACL is remembered).
3789 This code is intended to treat the data in the same way as lines in the main
3790 Exim configuration file. That is:
3792 . Leading spaces are ignored.
3794 . A \ at the end of a line is a continuation - trailing spaces after the \
3795 are permitted (this is because I don't believe in making invisible things
3796 significant). Leading spaces on the continued part of a line are ignored.
3798 . Physical lines starting (significantly) with # are totally ignored, and
3799 may appear within a sequence of backslash-continued lines.
3801 . Blank lines are ignored, but will end a sequence of continuations.
3804 Returns: a pointer to the next line
3808 static uschar *acl_text; /* Current pointer in the text */
3809 static uschar *acl_text_end; /* Points one past the terminating '0' */
3817 /* This loop handles leading blank lines and comments. */
3821 while (isspace(*acl_text)) acl_text++; /* Leading spaces/empty lines */
3822 if (*acl_text == 0) return NULL; /* No more data */
3823 yield = acl_text; /* Potential data line */
3825 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3827 /* If we hit the end before a newline, we have the whole logical line. If
3828 it's a comment, there's no more data to be given. Otherwise, yield it. */
3830 if (*acl_text == 0) return (*yield == '#')? NULL : yield;
3832 /* After reaching a newline, end this loop if the physical line does not
3833 start with '#'. If it does, it's a comment, and the loop continues. */
3835 if (*yield != '#') break;
3838 /* This loop handles continuations. We know we have some real data, ending in
3839 newline. See if there is a continuation marker at the end (ignoring trailing
3840 white space). We know that *yield is not white space, so no need to test for
3841 cont > yield in the backwards scanning loop. */
3846 for (cont = acl_text - 1; isspace(*cont); cont--);
3848 /* If no continuation follows, we are done. Mark the end of the line and
3857 /* We have encountered a continuation. Skip over whitespace at the start of
3858 the next line, and indeed the whole of the next line or lines if they are
3863 while (*(++acl_text) == ' ' || *acl_text == '\t');
3864 if (*acl_text != '#') break;
3865 while (*(++acl_text) != 0 && *acl_text != '\n');
3868 /* We have the start of a continuation line. Move all the rest of the data
3869 to join onto the previous line, and then find its end. If the end is not a
3870 newline, we are done. Otherwise loop to look for another continuation. */
3872 memmove(cont, acl_text, acl_text_end - acl_text);
3873 acl_text_end -= acl_text - cont;
3875 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3876 if (*acl_text == 0) return yield;
3879 /* Control does not reach here */
3886 /*************************************************
3887 * Check access using an ACL *
3888 *************************************************/
3890 /* This function is called from address_check. It may recurse via
3891 acl_check_condition() - hence the use of a level to stop looping. The ACL is
3892 passed as a string which is expanded. A forced failure implies no access check
3893 is required. If the result is a single word, it is taken as the name of an ACL
3894 which is sought in the global ACL tree. Otherwise, it is taken as literal ACL
3895 text, complete with newlines, and parsed as such. In both cases, the ACL check
3896 is then run. This function uses an auxiliary function for acl_read() to call
3897 for reading individual lines of a literal ACL. This is acl_getline(), which
3898 appears immediately above.
3901 where where called from
3902 addr address item when called from RCPT; otherwise NULL
3903 s the input string; NULL is the same as an empty ACL => DENY
3904 level the nesting level
3905 user_msgptr where to put a user error (for SMTP response)
3906 log_msgptr where to put a logging message (not for SMTP response)
3908 Returns: OK access is granted
3909 DISCARD access is apparently granted...
3910 FAIL access is denied
3911 FAIL_DROP access is denied; drop the connection
3912 DEFER can't tell at the moment
3917 acl_check_internal(int where, address_item *addr, uschar *s, int level,
3918 uschar **user_msgptr, uschar **log_msgptr)
3921 acl_block *acl = NULL;
3922 uschar *acl_name = US"inline ACL";
3925 /* Catch configuration loops */
3929 *log_msgptr = US"ACL nested too deep: possible loop";
3935 HDEBUG(D_acl) debug_printf("ACL is NULL: implicit DENY\n");
3939 /* At top level, we expand the incoming string. At lower levels, it has already
3940 been expanded as part of condition processing. */
3944 ss = expand_string(s);
3947 if (expand_string_forcedfail) return OK;
3948 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s", s,
3949 expand_string_message);
3955 while (isspace(*ss))ss++;
3957 /* If we can't find a named ACL, the default is to parse it as an inline one.
3958 (Unless it begins with a slash; non-existent files give rise to an error.) */
3962 /* Handle the case of a string that does not contain any spaces. Look for a
3963 named ACL among those read from the configuration, or a previously read file.
3964 It is possible that the pointer to the ACL is NULL if the configuration
3965 contains a name with no data. If not found, and the text begins with '/',
3966 read an ACL from a file, and save it so it can be re-used. */
3968 if (Ustrchr(ss, ' ') == NULL)
3970 tree_node *t = tree_search(acl_anchor, ss);
3973 acl = (acl_block *)(t->data.ptr);
3976 HDEBUG(D_acl) debug_printf("ACL \"%s\" is empty: implicit DENY\n", ss);
3979 acl_name = string_sprintf("ACL \"%s\"", ss);
3980 HDEBUG(D_acl) debug_printf("using ACL \"%s\"\n", ss);
3983 else if (*ss == '/')
3985 struct stat statbuf;
3986 fd = Uopen(ss, O_RDONLY, 0);
3989 *log_msgptr = string_sprintf("failed to open ACL file \"%s\": %s", ss,
3994 if (fstat(fd, &statbuf) != 0)
3996 *log_msgptr = string_sprintf("failed to fstat ACL file \"%s\": %s", ss,
4001 acl_text = store_get(statbuf.st_size + 1);
4002 acl_text_end = acl_text + statbuf.st_size + 1;
4004 if (read(fd, acl_text, statbuf.st_size) != statbuf.st_size)
4006 *log_msgptr = string_sprintf("failed to read ACL file \"%s\": %s",
4007 ss, strerror(errno));
4010 acl_text[statbuf.st_size] = 0;
4013 acl_name = string_sprintf("ACL \"%s\"", ss);
4014 HDEBUG(D_acl) debug_printf("read ACL from file %s\n", ss);
4018 /* Parse an ACL that is still in text form. If it came from a file, remember it
4019 in the ACL tree, having read it into the POOL_PERM store pool so that it
4020 persists between multiple messages. */
4024 int old_pool = store_pool;
4025 if (fd >= 0) store_pool = POOL_PERM;
4026 acl = acl_read(acl_getline, log_msgptr);
4027 store_pool = old_pool;
4028 if (acl == NULL && *log_msgptr != NULL) return ERROR;
4031 tree_node *t = store_get_perm(sizeof(tree_node) + Ustrlen(ss));
4032 Ustrcpy(t->name, ss);
4034 (void)tree_insertnode(&acl_anchor, t);
4038 /* Now we have an ACL to use. It's possible it may be NULL. */
4043 int basic_errno = 0;
4044 BOOL endpass_seen = FALSE;
4046 *log_msgptr = *user_msgptr = NULL;
4047 acl_temp_details = FALSE;
4049 if ((where == ACL_WHERE_QUIT || where == ACL_WHERE_NOTQUIT) &&
4050 acl->verb != ACL_ACCEPT &&
4051 acl->verb != ACL_WARN)
4053 *log_msgptr = string_sprintf("\"%s\" is not allowed in a QUIT or not-QUIT ACL",
4058 HDEBUG(D_acl) debug_printf("processing \"%s\"\n", verbs[acl->verb]);
4060 /* Clear out any search error message from a previous check before testing
4063 search_error_message = NULL;
4064 cond = acl_check_condition(acl->verb, acl->condition, where, addr, level,
4065 &endpass_seen, user_msgptr, log_msgptr, &basic_errno);
4067 /* Handle special returns: DEFER causes a return except on a WARN verb;
4068 ERROR always causes a return. */
4073 HDEBUG(D_acl) debug_printf("%s: condition test deferred in %s\n", verbs[acl->verb], acl_name);
4074 if (basic_errno != ERRNO_CALLOUTDEFER)
4076 if (search_error_message != NULL && *search_error_message != 0)
4077 *log_msgptr = search_error_message;
4078 if (smtp_return_error_details) acl_temp_details = TRUE;
4082 acl_temp_details = TRUE;
4084 if (acl->verb != ACL_WARN) return DEFER;
4087 default: /* Paranoia */
4089 HDEBUG(D_acl) debug_printf("%s: condition test error in %s\n", verbs[acl->verb], acl_name);
4093 HDEBUG(D_acl) debug_printf("%s: condition test succeeded in %s\n",
4094 verbs[acl->verb], acl_name);
4098 HDEBUG(D_acl) debug_printf("%s: condition test failed in %s\n", verbs[acl->verb], acl_name);
4101 /* DISCARD and DROP can happen only from a nested ACL condition, and
4102 DISCARD can happen only for an "accept" or "discard" verb. */
4105 HDEBUG(D_acl) debug_printf("%s: condition test yielded \"discard\" in %s\n",
4106 verbs[acl->verb], acl_name);
4110 HDEBUG(D_acl) debug_printf("%s: condition test yielded \"drop\" in %s\n",
4111 verbs[acl->verb], acl_name);
4115 /* At this point, cond for most verbs is either OK or FAIL or (as a result of
4116 a nested ACL condition) FAIL_DROP. However, for WARN, cond may be DEFER, and
4117 for ACCEPT and DISCARD, it may be DISCARD after a nested ACL call. */
4122 if (cond == OK || cond == DISCARD) return cond;
4125 HDEBUG(D_acl) debug_printf("accept: endpass encountered - denying access\n");
4133 acl_temp_details = TRUE;
4139 if (cond == OK) return FAIL;
4143 if (cond == OK || cond == DISCARD) return DISCARD;
4146 HDEBUG(D_acl) debug_printf("discard: endpass encountered - denying access\n");
4152 if (cond == OK) return FAIL_DROP;
4156 if (cond != OK) return cond;
4161 acl_warn(where, *user_msgptr, *log_msgptr);
4162 else if (cond == DEFER && (log_extra_selector & LX_acl_warn_skipped) != 0)
4163 log_write(0, LOG_MAIN, "%s Warning: ACL \"warn\" statement skipped: "
4164 "condition test deferred%s%s", host_and_ident(TRUE),
4165 (*log_msgptr == NULL)? US"" : US": ",
4166 (*log_msgptr == NULL)? US"" : *log_msgptr);
4167 *log_msgptr = *user_msgptr = NULL; /* In case implicit DENY follows */
4171 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown verb %d",
4176 /* Pass to the next ACL item */
4181 /* We have reached the end of the ACL. This is an implicit DENY. */
4183 HDEBUG(D_acl) debug_printf("end of %s: implicit DENY\n", acl_name);
4190 /* Same args as acl_check_internal() above, but the string s is
4191 the name of an ACL followed optionally by up to 9 space-separated arguments.
4192 The name and args are separately expanded. Args go into $acl_arg globals. */
4194 acl_check_wargs(int where, address_item *addr, uschar *s, int level,
4195 uschar **user_msgptr, uschar **log_msgptr)
4198 uschar * tmp_arg[9]; /* must match acl_arg[] */
4199 uschar * sav_arg[9]; /* must match acl_arg[] */
4205 if (!(tmp = string_dequote(&s)) || !(name = expand_string(tmp)))
4208 for (i = 0; i < 9; i++)
4210 while (*s && isspace(*s)) s++;
4212 if (!(tmp = string_dequote(&s)) || !(tmp_arg[i] = expand_string(tmp)))
4219 sav_narg = acl_narg;
4221 for (i = 0; i < acl_narg; i++)
4223 sav_arg[i] = acl_arg[i];
4224 acl_arg[i] = tmp_arg[i];
4228 sav_arg[i] = acl_arg[i];
4229 acl_arg[i++] = NULL;
4232 ret = acl_check_internal(where, addr, name, level, user_msgptr, log_msgptr);
4234 acl_narg = sav_narg;
4235 for (i = 0; i < 9; i++) acl_arg[i] = sav_arg[i];
4239 if (expand_string_forcedfail) return ERROR;
4240 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s",
4241 tmp, expand_string_message);
4242 return search_find_defer?DEFER:ERROR;
4247 /*************************************************
4248 * Check access using an ACL *
4249 *************************************************/
4251 /* Alternate interface for ACL, used by expansions */
4253 acl_eval(int where, uschar *s, uschar **user_msgptr, uschar **log_msgptr)
4256 address_item *addr = NULL;
4258 *user_msgptr = *log_msgptr = NULL;
4259 sender_verified_failed = NULL;
4260 ratelimiters_cmd = NULL;
4261 log_reject_target = LOG_MAIN|LOG_REJECT;
4263 if (where == ACL_WHERE_RCPT)
4265 adb = address_defaults;
4267 addr->address = expand_string(US"$local_part@$domain");
4268 addr->domain = deliver_domain;
4269 addr->local_part = deliver_localpart;
4270 addr->cc_local_part = deliver_localpart;
4271 addr->lc_local_part = deliver_localpart;
4274 return acl_check_internal(where, addr, s, 0, user_msgptr, log_msgptr);
4279 /* This is the external interface for ACL checks. It sets up an address and the
4280 expansions for $domain and $local_part when called after RCPT, then calls
4281 acl_check_internal() to do the actual work.
4284 where ACL_WHERE_xxxx indicating where called from
4285 recipient RCPT address for RCPT check, else NULL
4286 s the input string; NULL is the same as an empty ACL => DENY
4287 user_msgptr where to put a user error (for SMTP response)
4288 log_msgptr where to put a logging message (not for SMTP response)
4290 Returns: OK access is granted by an ACCEPT verb
4291 DISCARD access is granted by a DISCARD verb
4292 FAIL access is denied
4293 FAIL_DROP access is denied; drop the connection
4294 DEFER can't tell at the moment
4297 int acl_where = ACL_WHERE_UNKNOWN;
4300 acl_check(int where, uschar *recipient, uschar *s, uschar **user_msgptr,
4301 uschar **log_msgptr)
4305 address_item *addr = NULL;
4307 *user_msgptr = *log_msgptr = NULL;
4308 sender_verified_failed = NULL;
4309 ratelimiters_cmd = NULL;
4310 log_reject_target = LOG_MAIN|LOG_REJECT;
4312 #ifdef EXPERIMENTAL_PRDR
4313 if (where == ACL_WHERE_RCPT || where == ACL_WHERE_PRDR )
4315 if (where == ACL_WHERE_RCPT )
4318 adb = address_defaults;
4320 addr->address = recipient;
4321 if (deliver_split_address(addr) == DEFER)
4323 *log_msgptr = US"defer in percent_hack_domains check";
4326 deliver_domain = addr->domain;
4327 deliver_localpart = addr->local_part;
4331 rc = acl_check_internal(where, addr, s, 0, user_msgptr, log_msgptr);
4332 acl_where = ACL_WHERE_UNKNOWN;
4334 /* Cutthrough - if requested,
4335 and WHERE_RCPT and not yet opened conn as result of recipient-verify,
4336 and rcpt acl returned accept,
4337 and first recipient (cancel on any subsequents)
4338 open one now and run it up to RCPT acceptance.
4339 A failed verify should cancel cutthrough request.
4341 Initial implementation: dual-write to spool.
4342 Assume the rxd datastream is now being copied byte-for-byte to an open cutthrough connection.
4344 Cease cutthrough copy on rxd final dot; do not send one.
4346 On a data acl, if not accept and a cutthrough conn is open, hard-close it (no SMTP niceness).
4348 On data acl accept, terminate the dataphase on an open cutthrough conn. If accepted or
4349 perm-rejected, reflect that to the original sender - and dump the spooled copy.
4350 If temp-reject, close the conn (and keep the spooled copy).
4351 If conn-failure, no action (and keep the spooled copy).
4355 case ACL_WHERE_RCPT:
4356 #ifdef EXPERIMENTAL_PRDR
4357 case ACL_WHERE_PRDR:
4359 if( rcpt_count > 1 )
4360 cancel_cutthrough_connection("more than one recipient");
4361 else if (rc == OK && cutthrough_delivery && cutthrough_fd < 0)
4362 open_cutthrough_connection(addr);
4365 case ACL_WHERE_PREDATA:
4367 cutthrough_predata();
4369 cancel_cutthrough_connection("predata acl not ok");
4372 case ACL_WHERE_QUIT:
4373 case ACL_WHERE_NOTQUIT:
4374 cancel_cutthrough_connection("quit or notquit");
4381 deliver_domain = deliver_localpart = deliver_address_data =
4382 sender_address_data = NULL;
4384 /* A DISCARD response is permitted only for message ACLs, excluding the PREDATA
4385 ACL, which is really in the middle of an SMTP command. */
4389 if (where > ACL_WHERE_NOTSMTP || where == ACL_WHERE_PREDATA)
4391 log_write(0, LOG_MAIN|LOG_PANIC, "\"discard\" verb not allowed in %s "
4392 "ACL", acl_wherenames[where]);
4398 /* A DROP response is not permitted from MAILAUTH */
4400 if (rc == FAIL_DROP && where == ACL_WHERE_MAILAUTH)
4402 log_write(0, LOG_MAIN|LOG_PANIC, "\"drop\" verb not allowed in %s "
4403 "ACL", acl_wherenames[where]);
4407 /* Before giving a response, take a look at the length of any user message, and
4408 split it up into multiple lines if possible. */
4410 *user_msgptr = string_split_message(*user_msgptr);
4411 if (fake_response != OK)
4412 fake_response_text = string_split_message(fake_response_text);
4418 /*************************************************
4419 * Create ACL variable *
4420 *************************************************/
4422 /* Create an ACL variable or reuse an existing one. ACL variables are in a
4423 binary tree (see tree.c) with acl_var_c and acl_var_m as root nodes.
4426 name pointer to the variable's name, starting with c or m
4428 Returns the pointer to variable's tree node
4432 acl_var_create(uschar *name)
4434 tree_node *node, **root;
4435 root = (name[0] == 'c')? &acl_var_c : &acl_var_m;
4436 node = tree_search(*root, name);
4439 node = store_get(sizeof(tree_node) + Ustrlen(name));
4440 Ustrcpy(node->name, name);
4441 (void)tree_insertnode(root, node);
4443 node->data.ptr = NULL;
4449 /*************************************************
4450 * Write an ACL variable in spool format *
4451 *************************************************/
4453 /* This function is used as a callback for tree_walk when writing variables to
4454 the spool file. To retain spool file compatibility, what is written is -aclc or
4455 -aclm followed by the rest of the name and the data length, space separated,
4456 then the value itself, starting on a new line, and terminated by an additional
4457 newline. When we had only numbered ACL variables, the first line might look
4458 like this: "-aclc 5 20". Now it might be "-aclc foo 20" for the variable called
4462 name of the variable
4463 value of the variable
4464 ctx FILE pointer (as a void pointer)
4470 acl_var_write(uschar *name, uschar *value, void *ctx)
4472 FILE *f = (FILE *)ctx;
4473 fprintf(f, "-acl%c %s %d\n%s\n", name[0], name+1, Ustrlen(value), value);