1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2014 */
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 lookup_dnssec_authenticated = NULL;
1618 switch (dns_lookup(&dnsa, target, type, NULL))
1620 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1623 return t->data.val = CSA_DEFER_ADDR;
1625 /* If the query succeeded, scan the addresses and return the result. */
1628 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ANSWERS, target);
1629 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1630 /* else fall through */
1632 /* If the target has no IP addresses, the client cannot have an authorized
1633 IP address. However, if the target site uses A6 records (not AAAA records)
1634 we have to do yet another lookup in order to check them. */
1639 #if HAVE_IPV6 && defined(SUPPORT_A6)
1640 if (type == T_AAAA) { type = T_A6; goto DNS_LOOKUP_AGAIN; }
1643 return t->data.val = CSA_FAIL_NOADDR;
1649 /*************************************************
1650 * Handle verification (address & other) *
1651 *************************************************/
1653 enum { VERIFY_REV_HOST_LKUP, VERIFY_CERT, VERIFY_HELO, VERIFY_CSA, VERIFY_HDR_SYNTAX,
1654 VERIFY_NOT_BLIND, VERIFY_HDR_SNDR, VERIFY_SNDR, VERIFY_RCPT,
1655 VERIFY_HDR_NAMES_ASCII
1660 unsigned where_allowed; /* bitmap */
1661 BOOL no_options; /* Never has /option(s) following */
1662 unsigned alt_opt_sep; /* >0 Non-/ option separator (custom parser) */
1664 static verify_type_t verify_type_list[] = {
1665 { US"reverse_host_lookup", VERIFY_REV_HOST_LKUP, ~0, TRUE, 0 },
1666 { US"certificate", VERIFY_CERT, ~0, TRUE, 0 },
1667 { US"helo", VERIFY_HELO, ~0, TRUE, 0 },
1668 { US"csa", VERIFY_CSA, ~0, FALSE, 0 },
1669 { US"header_syntax", VERIFY_HDR_SYNTAX, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), TRUE, 0 },
1670 { US"not_blind", VERIFY_NOT_BLIND, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), TRUE, 0 },
1671 { US"header_sender", VERIFY_HDR_SNDR, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), FALSE, 0 },
1672 { US"sender", VERIFY_SNDR, (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)
1673 |(1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP),
1675 { US"recipient", VERIFY_RCPT, (1<<ACL_WHERE_RCPT), FALSE, 0 },
1676 { US"header_names_ascii", VERIFY_HDR_NAMES_ASCII, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), TRUE, 0 }
1680 enum { CALLOUT_DEFER_OK, CALLOUT_NOCACHE, CALLOUT_RANDOM, CALLOUT_USE_SENDER,
1681 CALLOUT_USE_POSTMASTER, CALLOUT_POSTMASTER, CALLOUT_FULLPOSTMASTER,
1682 CALLOUT_MAILFROM, CALLOUT_POSTMASTER_MAILFROM, CALLOUT_MAXWAIT, CALLOUT_CONNECT,
1689 BOOL has_option; /* Has =option(s) following */
1690 BOOL timeval; /* Has a time value */
1692 static callout_opt_t callout_opt_list[] = {
1693 { US"defer_ok", CALLOUT_DEFER_OK, 0, FALSE, FALSE },
1694 { US"no_cache", CALLOUT_NOCACHE, vopt_callout_no_cache, FALSE, FALSE },
1695 { US"random", CALLOUT_RANDOM, vopt_callout_random, FALSE, FALSE },
1696 { US"use_sender", CALLOUT_USE_SENDER, vopt_callout_recipsender, FALSE, FALSE },
1697 { US"use_postmaster", CALLOUT_USE_POSTMASTER,vopt_callout_recippmaster, FALSE, FALSE },
1698 { US"postmaster_mailfrom",CALLOUT_POSTMASTER_MAILFROM,0, TRUE, FALSE },
1699 { US"postmaster", CALLOUT_POSTMASTER, 0, FALSE, FALSE },
1700 { US"fullpostmaster", CALLOUT_FULLPOSTMASTER,vopt_callout_fullpm, FALSE, FALSE },
1701 { US"mailfrom", CALLOUT_MAILFROM, 0, TRUE, FALSE },
1702 { US"maxwait", CALLOUT_MAXWAIT, 0, TRUE, TRUE },
1703 { US"connect", CALLOUT_CONNECT, 0, TRUE, TRUE },
1704 { NULL, CALLOUT_TIME, 0, FALSE, TRUE }
1709 /* This function implements the "verify" condition. It is called when
1710 encountered in any ACL, because some tests are almost always permitted. Some
1711 just don't make sense, and always fail (for example, an attempt to test a host
1712 lookup for a non-TCP/IP message). Others are restricted to certain ACLs.
1715 where where called from
1716 addr the recipient address that the ACL is handling, or NULL
1717 arg the argument of "verify"
1718 user_msgptr pointer for user message
1719 log_msgptr pointer for log message
1720 basic_errno where to put verify errno
1722 Returns: OK verification condition succeeded
1723 FAIL verification failed
1724 DEFER there was a problem verifying
1729 acl_verify(int where, address_item *addr, uschar *arg,
1730 uschar **user_msgptr, uschar **log_msgptr, int *basic_errno)
1734 int callout_overall = -1;
1735 int callout_connect = -1;
1736 int verify_options = 0;
1738 BOOL verify_header_sender = FALSE;
1739 BOOL defer_ok = FALSE;
1740 BOOL callout_defer_ok = FALSE;
1741 BOOL no_details = FALSE;
1742 BOOL success_on_redirect = FALSE;
1743 address_item *sender_vaddr = NULL;
1744 uschar *verify_sender_address = NULL;
1745 uschar *pm_mailfrom = NULL;
1746 uschar *se_mailfrom = NULL;
1748 /* Some of the verify items have slash-separated options; some do not. Diagnose
1749 an error if options are given for items that don't expect them.
1752 uschar *slash = Ustrchr(arg, '/');
1754 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
1757 if (ss == NULL) goto BAD_VERIFY;
1759 /* Handle name/address consistency verification in a separate function. */
1761 for (vp= verify_type_list;
1762 (char *)vp < (char *)verify_type_list + sizeof(verify_type_list);
1765 if (vp->alt_opt_sep ? strncmpic(ss, vp->name, vp->alt_opt_sep) == 0
1766 : strcmpic (ss, vp->name) == 0)
1768 if ((char *)vp >= (char *)verify_type_list + sizeof(verify_type_list))
1771 if (vp->no_options && slash != NULL)
1773 *log_msgptr = string_sprintf("unexpected '/' found in \"%s\" "
1774 "(this verify item has no options)", arg);
1777 if (!(vp->where_allowed & (1<<where)))
1779 *log_msgptr = string_sprintf("cannot verify %s in ACL for %s", vp->name, acl_wherenames[where]);
1784 case VERIFY_REV_HOST_LKUP:
1785 if (sender_host_address == NULL) return OK;
1786 return acl_verify_reverse(user_msgptr, log_msgptr);
1789 /* TLS certificate verification is done at STARTTLS time; here we just
1790 test whether it was successful or not. (This is for optional verification; for
1791 mandatory verification, the connection doesn't last this long.) */
1793 if (tls_in.certificate_verified) return OK;
1794 *user_msgptr = US"no verified certificate";
1798 /* We can test the result of optional HELO verification that might have
1799 occurred earlier. If not, we can attempt the verification now. */
1801 if (!helo_verified && !helo_verify_failed) smtp_verify_helo();
1802 return helo_verified? OK : FAIL;
1805 /* Do Client SMTP Authorization checks in a separate function, and turn the
1806 result code into user-friendly strings. */
1808 rc = acl_verify_csa(list);
1809 *log_msgptr = *user_msgptr = string_sprintf("client SMTP authorization %s",
1810 csa_reason_string[rc]);
1811 csa_status = csa_status_string[rc];
1812 DEBUG(D_acl) debug_printf("CSA result %s\n", csa_status);
1813 return csa_return_code[rc];
1815 case VERIFY_HDR_SYNTAX:
1816 /* Check that all relevant header lines have the correct syntax. If there is
1817 a syntax error, we return details of the error to the sender if configured to
1818 send out full details. (But a "message" setting on the ACL can override, as
1821 rc = verify_check_headers(log_msgptr);
1822 if (rc != OK && smtp_return_error_details && *log_msgptr != NULL)
1823 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1826 case VERIFY_HDR_NAMES_ASCII:
1827 /* Check that all header names are true 7 bit strings
1828 See RFC 5322, 2.2. and RFC 6532, 3. */
1830 rc = verify_check_header_names_ascii(log_msgptr);
1831 if (rc != OK && smtp_return_error_details && *log_msgptr != NULL)
1832 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1835 case VERIFY_NOT_BLIND:
1836 /* Check that no recipient of this message is "blind", that is, every envelope
1837 recipient must be mentioned in either To: or Cc:. */
1839 rc = verify_check_notblind();
1842 *log_msgptr = string_sprintf("bcc recipient detected");
1843 if (smtp_return_error_details)
1844 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1848 /* The remaining verification tests check recipient and sender addresses,
1849 either from the envelope or from the header. There are a number of
1850 slash-separated options that are common to all of them. */
1852 case VERIFY_HDR_SNDR:
1853 verify_header_sender = TRUE;
1857 /* In the case of a sender, this can optionally be followed by an address to use
1858 in place of the actual sender (rare special-case requirement). */
1862 verify_sender_address = sender_address;
1865 while (isspace(*s)) s++;
1866 if (*s++ != '=') goto BAD_VERIFY;
1867 while (isspace(*s)) s++;
1868 verify_sender_address = string_copy(s);
1879 /* Remaining items are optional; they apply to sender and recipient
1880 verification, including "header sender" verification. */
1882 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size))
1885 if (strcmpic(ss, US"defer_ok") == 0) defer_ok = TRUE;
1886 else if (strcmpic(ss, US"no_details") == 0) no_details = TRUE;
1887 else if (strcmpic(ss, US"success_on_redirect") == 0) success_on_redirect = TRUE;
1889 /* These two old options are left for backwards compatibility */
1891 else if (strcmpic(ss, US"callout_defer_ok") == 0)
1893 callout_defer_ok = TRUE;
1894 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1897 else if (strcmpic(ss, US"check_postmaster") == 0)
1900 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1903 /* The callout option has a number of sub-options, comma separated */
1905 else if (strncmpic(ss, US"callout", 7) == 0)
1907 callout = CALLOUT_TIMEOUT_DEFAULT;
1911 while (isspace(*ss)) ss++;
1917 while (isspace(*ss)) ss++;
1919 while ((opt = string_nextinlist(&ss, &optsep, buffer, sizeof(buffer)))
1923 double period = 1.0F;
1925 for (op= callout_opt_list; op->name; op++)
1926 if (strncmpic(opt, op->name, Ustrlen(op->name)) == 0)
1929 verify_options |= op->flag;
1932 opt += Ustrlen(op->name);
1933 while (isspace(*opt)) opt++;
1936 *log_msgptr = string_sprintf("'=' expected after "
1937 "\"%s\" in ACL verify condition \"%s\"", op->name, arg);
1940 while (isspace(*opt)) opt++;
1944 period = readconf_readtime(opt, 0, FALSE);
1947 *log_msgptr = string_sprintf("bad time value in ACL condition "
1948 "\"verify %s\"", arg);
1955 case CALLOUT_DEFER_OK: callout_defer_ok = TRUE; break;
1956 case CALLOUT_POSTMASTER: pm_mailfrom = US""; break;
1957 case CALLOUT_FULLPOSTMASTER: pm_mailfrom = US""; break;
1958 case CALLOUT_MAILFROM:
1959 if (!verify_header_sender)
1961 *log_msgptr = string_sprintf("\"mailfrom\" is allowed as a "
1962 "callout option only for verify=header_sender (detected in ACL "
1963 "condition \"%s\")", arg);
1966 se_mailfrom = string_copy(opt);
1968 case CALLOUT_POSTMASTER_MAILFROM: pm_mailfrom = string_copy(opt); break;
1969 case CALLOUT_MAXWAIT: callout_overall = period; break;
1970 case CALLOUT_CONNECT: callout_connect = period; break;
1971 case CALLOUT_TIME: callout = period; break;
1977 *log_msgptr = string_sprintf("'=' expected after \"callout\" in "
1978 "ACL condition \"%s\"", arg);
1984 /* Option not recognized */
1988 *log_msgptr = string_sprintf("unknown option \"%s\" in ACL "
1989 "condition \"verify %s\"", ss, arg);
1994 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster)) ==
1995 (vopt_callout_recipsender|vopt_callout_recippmaster))
1997 *log_msgptr = US"only one of use_sender and use_postmaster can be set "
1998 "for a recipient callout";
2002 /* Handle sender-in-header verification. Default the user message to the log
2003 message if giving out verification details. */
2005 if (verify_header_sender)
2008 rc = verify_check_header_address(user_msgptr, log_msgptr, callout,
2009 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, verify_options,
2013 *basic_errno = verrno;
2014 if (smtp_return_error_details)
2016 if (*user_msgptr == NULL && *log_msgptr != NULL)
2017 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
2018 if (rc == DEFER) acl_temp_details = TRUE;
2023 /* Handle a sender address. The default is to verify *the* sender address, but
2024 optionally a different address can be given, for special requirements. If the
2025 address is empty, we are dealing with a bounce message that has no sender, so
2026 we cannot do any checking. If the real sender address gets rewritten during
2027 verification (e.g. DNS widening), set the flag to stop it being rewritten again
2028 during message reception.
2030 A list of verified "sender" addresses is kept to try to avoid doing to much
2031 work repetitively when there are multiple recipients in a message and they all
2032 require sender verification. However, when callouts are involved, it gets too
2033 complicated because different recipients may require different callout options.
2034 Therefore, we always do a full sender verify when any kind of callout is
2035 specified. Caching elsewhere, for instance in the DNS resolver and in the
2036 callout handling, should ensure that this is not terribly inefficient. */
2038 else if (verify_sender_address != NULL)
2040 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster))
2043 *log_msgptr = US"use_sender or use_postmaster cannot be used for a "
2044 "sender verify callout";
2048 sender_vaddr = verify_checked_sender(verify_sender_address);
2049 if (sender_vaddr != NULL && /* Previously checked */
2050 callout <= 0) /* No callout needed this time */
2052 /* If the "routed" flag is set, it means that routing worked before, so
2053 this check can give OK (the saved return code value, if set, belongs to a
2054 callout that was done previously). If the "routed" flag is not set, routing
2055 must have failed, so we use the saved return code. */
2057 if (testflag(sender_vaddr, af_verify_routed)) rc = OK; else
2059 rc = sender_vaddr->special_action;
2060 *basic_errno = sender_vaddr->basic_errno;
2062 HDEBUG(D_acl) debug_printf("using cached sender verify result\n");
2065 /* Do a new verification, and cache the result. The cache is used to avoid
2066 verifying the sender multiple times for multiple RCPTs when callouts are not
2067 specified (see comments above).
2069 The cache is also used on failure to give details in response to the first
2070 RCPT that gets bounced for this reason. However, this can be suppressed by
2071 the no_details option, which sets the flag that says "this detail has already
2072 been sent". The cache normally contains just one address, but there may be
2073 more in esoteric circumstances. */
2078 uschar *save_address_data = deliver_address_data;
2080 sender_vaddr = deliver_make_addr(verify_sender_address, TRUE);
2081 if (no_details) setflag(sender_vaddr, af_sverify_told);
2082 if (verify_sender_address[0] != 0)
2084 /* If this is the real sender address, save the unrewritten version
2085 for use later in receive. Otherwise, set a flag so that rewriting the
2086 sender in verify_address() does not update sender_address. */
2088 if (verify_sender_address == sender_address)
2089 sender_address_unrewritten = sender_address;
2091 verify_options |= vopt_fake_sender;
2093 if (success_on_redirect)
2094 verify_options |= vopt_success_on_redirect;
2096 /* The recipient, qualify, and expn options are never set in
2099 rc = verify_address(sender_vaddr, NULL, verify_options, callout,
2100 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, &routed);
2102 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
2106 if (Ustrcmp(sender_vaddr->address, verify_sender_address) != 0)
2108 DEBUG(D_acl) debug_printf("sender %s verified ok as %s\n",
2109 verify_sender_address, sender_vaddr->address);
2113 DEBUG(D_acl) debug_printf("sender %s verified ok\n",
2114 verify_sender_address);
2117 else *basic_errno = sender_vaddr->basic_errno;
2119 else rc = OK; /* Null sender */
2121 /* Cache the result code */
2123 if (routed) setflag(sender_vaddr, af_verify_routed);
2124 if (callout > 0) setflag(sender_vaddr, af_verify_callout);
2125 sender_vaddr->special_action = rc;
2126 sender_vaddr->next = sender_verified_list;
2127 sender_verified_list = sender_vaddr;
2129 /* Restore the recipient address data, which might have been clobbered by
2130 the sender verification. */
2132 deliver_address_data = save_address_data;
2135 /* Put the sender address_data value into $sender_address_data */
2137 sender_address_data = sender_vaddr->p.address_data;
2140 /* A recipient address just gets a straightforward verify; again we must handle
2141 the DEFER overrides. */
2147 if (success_on_redirect)
2148 verify_options |= vopt_success_on_redirect;
2150 /* We must use a copy of the address for verification, because it might
2154 rc = verify_address(&addr2, NULL, verify_options|vopt_is_recipient, callout,
2155 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, NULL);
2156 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
2158 *basic_errno = addr2.basic_errno;
2159 *log_msgptr = addr2.message;
2160 *user_msgptr = (addr2.user_message != NULL)?
2161 addr2.user_message : addr2.message;
2163 /* Allow details for temporary error if the address is so flagged. */
2164 if (testflag((&addr2), af_pass_message)) acl_temp_details = TRUE;
2166 /* Make $address_data visible */
2167 deliver_address_data = addr2.p.address_data;
2170 /* We have a result from the relevant test. Handle defer overrides first. */
2172 if (rc == DEFER && (defer_ok ||
2173 (callout_defer_ok && *basic_errno == ERRNO_CALLOUTDEFER)))
2175 HDEBUG(D_acl) debug_printf("verify defer overridden by %s\n",
2176 defer_ok? "defer_ok" : "callout_defer_ok");
2180 /* If we've failed a sender, set up a recipient message, and point
2181 sender_verified_failed to the address item that actually failed. */
2183 if (rc != OK && verify_sender_address != NULL)
2187 *log_msgptr = *user_msgptr = US"Sender verify failed";
2189 else if (*basic_errno != ERRNO_CALLOUTDEFER)
2191 *log_msgptr = *user_msgptr = US"Could not complete sender verify";
2195 *log_msgptr = US"Could not complete sender verify callout";
2196 *user_msgptr = smtp_return_error_details? sender_vaddr->user_message :
2200 sender_verified_failed = sender_vaddr;
2203 /* Verifying an address messes up the values of $domain and $local_part,
2204 so reset them before returning if this is a RCPT ACL. */
2208 deliver_domain = addr->domain;
2209 deliver_localpart = addr->local_part;
2213 /* Syntax errors in the verify argument come here. */
2216 *log_msgptr = string_sprintf("expected \"sender[=address]\", \"recipient\", "
2217 "\"helo\", \"header_syntax\", \"header_sender\", \"header_names_ascii\" "
2218 "or \"reverse_host_lookup\" at start of ACL condition "
2219 "\"verify %s\"", arg);
2226 /*************************************************
2227 * Check argument for control= modifier *
2228 *************************************************/
2230 /* Called from acl_check_condition() below
2233 arg the argument string for control=
2234 pptr set to point to the terminating character
2235 where which ACL we are in
2236 log_msgptr for error messages
2238 Returns: CONTROL_xxx value
2242 decode_control(uschar *arg, uschar **pptr, int where, uschar **log_msgptr)
2247 for (d = controls_list;
2248 d < controls_list + sizeof(controls_list)/sizeof(control_def);
2251 len = Ustrlen(d->name);
2252 if (Ustrncmp(d->name, arg, len) == 0) break;
2255 if (d >= controls_list + sizeof(controls_list)/sizeof(control_def) ||
2256 (arg[len] != 0 && (!d->has_option || arg[len] != '/')))
2258 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
2259 return CONTROL_ERROR;
2269 /*************************************************
2270 * Return a ratelimit error *
2271 *************************************************/
2273 /* Called from acl_ratelimit() below
2276 log_msgptr for error messages
2277 format format string
2278 ... supplementary arguments
2279 ss ratelimit option name
2280 where ACL_WHERE_xxxx indicating which ACL this is
2286 ratelimit_error(uschar **log_msgptr, const char *format, ...)
2289 uschar buffer[STRING_SPRINTF_BUFFER_SIZE];
2290 va_start(ap, format);
2291 if (!string_vformat(buffer, sizeof(buffer), format, ap))
2292 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
2293 "string_sprintf expansion was longer than " SIZE_T_FMT, sizeof(buffer));
2295 *log_msgptr = string_sprintf(
2296 "error in arguments to \"ratelimit\" condition: %s", buffer);
2303 /*************************************************
2304 * Handle rate limiting *
2305 *************************************************/
2307 /* Called by acl_check_condition() below to calculate the result
2308 of the ACL ratelimit condition.
2310 Note that the return value might be slightly unexpected: if the
2311 sender's rate is above the limit then the result is OK. This is
2312 similar to the dnslists condition, and is so that you can write
2313 ACL clauses like: defer ratelimit = 15 / 1h
2316 arg the option string for ratelimit=
2317 where ACL_WHERE_xxxx indicating which ACL this is
2318 log_msgptr for error messages
2320 Returns: OK - Sender's rate is above limit
2321 FAIL - Sender's rate is below limit
2322 DEFER - Problem opening ratelimit database
2323 ERROR - Syntax error in options.
2327 acl_ratelimit(uschar *arg, int where, uschar **log_msgptr)
2329 double limit, period, count;
2332 uschar *unique = NULL;
2334 BOOL leaky = FALSE, strict = FALSE, readonly = FALSE;
2335 BOOL noupdate = FALSE, badacl = FALSE;
2336 int mode = RATE_PER_WHAT;
2338 tree_node **anchor, *t;
2339 open_db dbblock, *dbm;
2341 dbdata_ratelimit *dbd;
2342 dbdata_ratelimit_unique *dbdb;
2345 /* Parse the first two options and record their values in expansion
2346 variables. These variables allow the configuration to have informative
2347 error messages based on rate limits obtained from a table lookup. */
2349 /* First is the maximum number of messages per period / maximum burst
2350 size, which must be greater than or equal to zero. Zero is useful for
2351 rate measurement as opposed to rate limiting. */
2353 sender_rate_limit = string_nextinlist(&arg, &sep, NULL, 0);
2354 if (sender_rate_limit == NULL)
2358 limit = Ustrtod(sender_rate_limit, &ss);
2359 if (tolower(*ss) == 'k') { limit *= 1024.0; ss++; }
2360 else if (tolower(*ss) == 'm') { limit *= 1024.0*1024.0; ss++; }
2361 else if (tolower(*ss) == 'g') { limit *= 1024.0*1024.0*1024.0; ss++; }
2363 if (limit < 0.0 || *ss != '\0')
2364 return ratelimit_error(log_msgptr,
2365 "\"%s\" is not a positive number", sender_rate_limit);
2367 /* Second is the rate measurement period / exponential smoothing time
2368 constant. This must be strictly greater than zero, because zero leads to
2369 run-time division errors. */
2371 sender_rate_period = string_nextinlist(&arg, &sep, NULL, 0);
2372 if (sender_rate_period == NULL) period = -1.0;
2373 else period = readconf_readtime(sender_rate_period, 0, FALSE);
2375 return ratelimit_error(log_msgptr,
2376 "\"%s\" is not a time value", sender_rate_period);
2378 /* By default we are counting one of something, but the per_rcpt,
2379 per_byte, and count options can change this. */
2383 /* Parse the other options. */
2385 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2388 if (strcmpic(ss, US"leaky") == 0) leaky = TRUE;
2389 else if (strcmpic(ss, US"strict") == 0) strict = TRUE;
2390 else if (strcmpic(ss, US"noupdate") == 0) noupdate = TRUE;
2391 else if (strcmpic(ss, US"readonly") == 0) readonly = TRUE;
2392 else if (strcmpic(ss, US"per_cmd") == 0) RATE_SET(mode, PER_CMD);
2393 else if (strcmpic(ss, US"per_conn") == 0)
2395 RATE_SET(mode, PER_CONN);
2396 if (where == ACL_WHERE_NOTSMTP || where == ACL_WHERE_NOTSMTP_START)
2399 else if (strcmpic(ss, US"per_mail") == 0)
2401 RATE_SET(mode, PER_MAIL);
2402 if (where > ACL_WHERE_NOTSMTP) badacl = TRUE;
2404 else if (strcmpic(ss, US"per_rcpt") == 0)
2406 /* If we are running in the RCPT ACL, then we'll count the recipients
2407 one by one, but if we are running when we have accumulated the whole
2408 list then we'll add them all in one batch. */
2409 if (where == ACL_WHERE_RCPT)
2410 RATE_SET(mode, PER_RCPT);
2411 else if (where >= ACL_WHERE_PREDATA && where <= ACL_WHERE_NOTSMTP)
2412 RATE_SET(mode, PER_ALLRCPTS), count = (double)recipients_count;
2413 else if (where == ACL_WHERE_MAIL || where > ACL_WHERE_NOTSMTP)
2414 RATE_SET(mode, PER_RCPT), badacl = TRUE;
2416 else if (strcmpic(ss, US"per_byte") == 0)
2418 /* If we have not yet received the message data and there was no SIZE
2419 declaration on the MAIL comand, then it's safe to just use a value of
2420 zero and let the recorded rate decay as if nothing happened. */
2421 RATE_SET(mode, PER_MAIL);
2422 if (where > ACL_WHERE_NOTSMTP) badacl = TRUE;
2423 else count = message_size < 0 ? 0.0 : (double)message_size;
2425 else if (strcmpic(ss, US"per_addr") == 0)
2427 RATE_SET(mode, PER_RCPT);
2428 if (where != ACL_WHERE_RCPT) badacl = TRUE, unique = US"*";
2429 else unique = string_sprintf("%s@%s", deliver_localpart, deliver_domain);
2431 else if (strncmpic(ss, US"count=", 6) == 0)
2434 count = Ustrtod(ss+6, &e);
2435 if (count < 0.0 || *e != '\0')
2436 return ratelimit_error(log_msgptr,
2437 "\"%s\" is not a positive number", ss);
2439 else if (strncmpic(ss, US"unique=", 7) == 0)
2440 unique = string_copy(ss + 7);
2441 else if (key == NULL)
2442 key = string_copy(ss);
2444 key = string_sprintf("%s/%s", key, ss);
2447 /* Sanity check. When the badacl flag is set the update mode must either
2448 be readonly (which is the default if it is omitted) or, for backwards
2449 compatibility, a combination of noupdate and strict or leaky. */
2451 if (mode == RATE_PER_CLASH)
2452 return ratelimit_error(log_msgptr, "conflicting per_* options");
2453 if (leaky + strict + readonly > 1)
2454 return ratelimit_error(log_msgptr, "conflicting update modes");
2455 if (badacl && (leaky || strict) && !noupdate)
2456 return ratelimit_error(log_msgptr,
2457 "\"%s\" must not have /leaky or /strict option in %s ACL",
2458 ratelimit_option_string[mode], acl_wherenames[where]);
2460 /* Set the default values of any unset options. In readonly mode we
2461 perform the rate computation without any increment so that its value
2462 decays to eventually allow over-limit senders through. */
2464 if (noupdate) readonly = TRUE, leaky = strict = FALSE;
2465 if (badacl) readonly = TRUE;
2466 if (readonly) count = 0.0;
2467 if (!strict && !readonly) leaky = TRUE;
2468 if (mode == RATE_PER_WHAT) mode = RATE_PER_MAIL;
2470 /* Create the lookup key. If there is no explicit key, use sender_host_address.
2471 If there is no sender_host_address (e.g. -bs or acl_not_smtp) then we simply
2472 omit it. The smoothing constant (sender_rate_period) and the per_xxx options
2473 are added to the key because they alter the meaning of the stored data. */
2476 key = (sender_host_address == NULL)? US"" : sender_host_address;
2478 key = string_sprintf("%s/%s/%s%s",
2480 ratelimit_option_string[mode],
2481 unique == NULL ? "" : "unique/",
2485 debug_printf("ratelimit condition count=%.0f %.1f/%s\n", count, limit, key);
2487 /* See if we have already computed the rate by looking in the relevant tree.
2488 For per-connection rate limiting, store tree nodes and dbdata in the permanent
2489 pool so that they survive across resets. In readonly mode we only remember the
2490 result for the rest of this command in case a later command changes it. After
2491 this bit of logic the code is independent of the per_* mode. */
2493 old_pool = store_pool;
2496 anchor = &ratelimiters_cmd;
2499 anchor = &ratelimiters_conn;
2500 store_pool = POOL_PERM;
2504 case RATE_PER_ALLRCPTS:
2505 anchor = &ratelimiters_mail;
2510 anchor = &ratelimiters_cmd;
2513 anchor = NULL; /* silence an "unused" complaint */
2514 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
2515 "internal ACL error: unknown ratelimit mode %d", mode);
2519 t = tree_search(*anchor, key);
2523 /* The following few lines duplicate some of the code below. */
2524 rc = (dbd->rate < limit)? FAIL : OK;
2525 store_pool = old_pool;
2526 sender_rate = string_sprintf("%.1f", dbd->rate);
2528 debug_printf("ratelimit found pre-computed rate %s\n", sender_rate);
2532 /* We aren't using a pre-computed rate, so get a previously recorded rate
2533 from the database, which will be updated and written back if required. */
2535 dbm = dbfn_open(US"ratelimit", O_RDWR, &dbblock, TRUE);
2538 store_pool = old_pool;
2540 HDEBUG(D_acl) debug_printf("ratelimit database not available\n");
2541 *log_msgptr = US"ratelimit database not available";
2544 dbdb = dbfn_read_with_length(dbm, key, &dbdb_size);
2547 gettimeofday(&tv, NULL);
2551 /* Locate the basic ratelimit block inside the DB data. */
2552 HDEBUG(D_acl) debug_printf("ratelimit found key in database\n");
2555 /* Forget the old Bloom filter if it is too old, so that we count each
2556 repeating event once per period. We don't simply clear and re-use the old
2557 filter because we want its size to change if the limit changes. Note that
2558 we keep the dbd pointer for copying the rate into the new data block. */
2560 if(unique != NULL && tv.tv_sec > dbdb->bloom_epoch + period)
2562 HDEBUG(D_acl) debug_printf("ratelimit discarding old Bloom filter\n");
2568 if(unique != NULL && dbdb_size < sizeof(*dbdb))
2570 HDEBUG(D_acl) debug_printf("ratelimit discarding undersize Bloom filter\n");
2575 /* Allocate a new data block if the database lookup failed
2576 or the Bloom filter passed its age limit. */
2582 /* No Bloom filter. This basic ratelimit block is initialized below. */
2583 HDEBUG(D_acl) debug_printf("ratelimit creating new rate data block\n");
2584 dbdb_size = sizeof(*dbd);
2585 dbdb = store_get(dbdb_size);
2590 HDEBUG(D_acl) debug_printf("ratelimit creating new Bloom filter\n");
2592 /* See the long comment below for an explanation of the magic number 2.
2593 The filter has a minimum size in case the rate limit is very small;
2594 this is determined by the definition of dbdata_ratelimit_unique. */
2596 extra = (int)limit * 2 - sizeof(dbdb->bloom);
2597 if (extra < 0) extra = 0;
2598 dbdb_size = sizeof(*dbdb) + extra;
2599 dbdb = store_get(dbdb_size);
2600 dbdb->bloom_epoch = tv.tv_sec;
2601 dbdb->bloom_size = sizeof(dbdb->bloom) + extra;
2602 memset(dbdb->bloom, 0, dbdb->bloom_size);
2604 /* Preserve any basic ratelimit data (which is our longer-term memory)
2605 by copying it from the discarded block. */
2615 /* If we are counting unique events, find out if this event is new or not.
2616 If the client repeats the event during the current period then it should be
2617 counted. We skip this code in readonly mode for efficiency, because any
2618 changes to the filter will be discarded and because count is already set to
2621 if (unique != NULL && !readonly)
2623 /* We identify unique events using a Bloom filter. (You can find my
2624 notes on Bloom filters at http://fanf.livejournal.com/81696.html)
2625 With the per_addr option, an "event" is a recipient address, though the
2626 user can use the unique option to define their own events. We only count
2627 an event if we have not seen it before.
2629 We size the filter according to the rate limit, which (in leaky mode)
2630 is the limit on the population of the filter. We allow 16 bits of space
2631 per entry (see the construction code above) and we set (up to) 8 of them
2632 when inserting an element (see the loop below). The probability of a false
2633 positive (an event we have not seen before but which we fail to count) is
2637 allzero = exp(-numhash * pop / size)
2638 = exp(-0.5 * pop / limit)
2639 fpr = pow(1 - allzero, numhash)
2641 For senders at the limit the fpr is 0.06% or 1 in 1700
2642 and for senders at half the limit it is 0.0006% or 1 in 170000
2644 In strict mode the Bloom filter can fill up beyond the normal limit, in
2645 which case the false positive rate will rise. This means that the
2646 measured rate for very fast senders can bogusly drop off after a while.
2648 At twice the limit, the fpr is 2.5% or 1 in 40
2649 At four times the limit, it is 31% or 1 in 3.2
2651 It takes ln(pop/limit) periods for an over-limit burst of pop events to
2652 decay below the limit, and if this is more than one then the Bloom filter
2653 will be discarded before the decay gets that far. The false positive rate
2654 at this threshold is 9.3% or 1 in 10.7. */
2657 unsigned n, hash, hinc;
2661 /* Instead of using eight independent hash values, we combine two values
2662 using the formula h1 + n * h2. This does not harm the Bloom filter's
2663 performance, and means the amount of hash we need is independent of the
2664 number of bits we set in the filter. */
2666 md5_start(&md5info);
2667 md5_end(&md5info, unique, Ustrlen(unique), md5sum);
2668 hash = md5sum[0] | md5sum[1] << 8 | md5sum[2] << 16 | md5sum[3] << 24;
2669 hinc = md5sum[4] | md5sum[5] << 8 | md5sum[6] << 16 | md5sum[7] << 24;
2671 /* Scan the bits corresponding to this event. A zero bit means we have
2672 not seen it before. Ensure all bits are set to record this event. */
2674 HDEBUG(D_acl) debug_printf("ratelimit checking uniqueness of %s\n", unique);
2677 for (n = 0; n < 8; n++, hash += hinc)
2679 int bit = 1 << (hash % 8);
2680 int byte = (hash / 8) % dbdb->bloom_size;
2681 if ((dbdb->bloom[byte] & bit) == 0)
2683 dbdb->bloom[byte] |= bit;
2688 /* If this event has occurred before, do not count it. */
2692 HDEBUG(D_acl) debug_printf("ratelimit event found in Bloom filter\n");
2696 HDEBUG(D_acl) debug_printf("ratelimit event added to Bloom filter\n");
2699 /* If there was no previous ratelimit data block for this key, initialize
2700 the new one, otherwise update the block from the database. The initial rate
2701 is what would be computed by the code below for an infinite interval. */
2705 HDEBUG(D_acl) debug_printf("ratelimit initializing new key's rate data\n");
2707 dbd->time_stamp = tv.tv_sec;
2708 dbd->time_usec = tv.tv_usec;
2713 /* The smoothed rate is computed using an exponentially weighted moving
2714 average adjusted for variable sampling intervals. The standard EWMA for
2715 a fixed sampling interval is: f'(t) = (1 - a) * f(t) + a * f'(t - 1)
2716 where f() is the measured value and f'() is the smoothed value.
2718 Old data decays out of the smoothed value exponentially, such that data n
2719 samples old is multiplied by a^n. The exponential decay time constant p
2720 is defined such that data p samples old is multiplied by 1/e, which means
2721 that a = exp(-1/p). We can maintain the same time constant for a variable
2722 sampling interval i by using a = exp(-i/p).
2724 The rate we are measuring is messages per period, suitable for directly
2725 comparing with the limit. The average rate between now and the previous
2726 message is period / interval, which we feed into the EWMA as the sample.
2728 It turns out that the number of messages required for the smoothed rate
2729 to reach the limit when they are sent in a burst is equal to the limit.
2730 This can be seen by analysing the value of the smoothed rate after N
2731 messages sent at even intervals. Let k = (1 - a) * p/i
2733 rate_1 = (1 - a) * p/i + a * rate_0
2735 rate_2 = k + a * rate_1
2736 = k + a * k + a^2 * rate_0
2737 rate_3 = k + a * k + a^2 * k + a^3 * rate_0
2738 rate_N = rate_0 * a^N + k * SUM(x=0..N-1)(a^x)
2739 = rate_0 * a^N + k * (1 - a^N) / (1 - a)
2740 = rate_0 * a^N + p/i * (1 - a^N)
2742 When N is large, a^N -> 0 so rate_N -> p/i as desired.
2744 rate_N = p/i + (rate_0 - p/i) * a^N
2745 a^N = (rate_N - p/i) / (rate_0 - p/i)
2746 N * -i/p = log((rate_N - p/i) / (rate_0 - p/i))
2747 N = p/i * log((rate_0 - p/i) / (rate_N - p/i))
2749 Numerical analysis of the above equation, setting the computed rate to
2750 increase from rate_0 = 0 to rate_N = limit, shows that for large sending
2751 rates, p/i, the number of messages N = limit. So limit serves as both the
2752 maximum rate measured in messages per period, and the maximum number of
2753 messages that can be sent in a fast burst. */
2755 double this_time = (double)tv.tv_sec
2756 + (double)tv.tv_usec / 1000000.0;
2757 double prev_time = (double)dbd->time_stamp
2758 + (double)dbd->time_usec / 1000000.0;
2760 /* We must avoid division by zero, and deal gracefully with the clock going
2761 backwards. If we blunder ahead when time is in reverse then the computed
2762 rate will be bogus. To be safe we clamp interval to a very small number. */
2764 double interval = this_time - prev_time <= 0.0 ? 1e-9
2765 : this_time - prev_time;
2767 double i_over_p = interval / period;
2768 double a = exp(-i_over_p);
2770 /* Combine the instantaneous rate (period / interval) with the previous rate
2771 using the smoothing factor a. In order to measure sized events, multiply the
2772 instantaneous rate by the count of bytes or recipients etc. */
2774 dbd->time_stamp = tv.tv_sec;
2775 dbd->time_usec = tv.tv_usec;
2776 dbd->rate = (1 - a) * count / i_over_p + a * dbd->rate;
2778 /* When events are very widely spaced the computed rate tends towards zero.
2779 Although this is accurate it turns out not to be useful for our purposes,
2780 especially when the first event after a long silence is the start of a spam
2781 run. A more useful model is that the rate for an isolated event should be the
2782 size of the event per the period size, ignoring the lack of events outside
2783 the current period and regardless of where the event falls in the period. So,
2784 if the interval was so long that the calculated rate is unhelpfully small, we
2785 re-intialize the rate. In the absence of higher-rate bursts, the condition
2786 below is true if the interval is greater than the period. */
2788 if (dbd->rate < count) dbd->rate = count;
2791 /* Clients sending at the limit are considered to be over the limit.
2792 This matters for edge cases such as a limit of zero, when the client
2793 should be completely blocked. */
2795 rc = (dbd->rate < limit)? FAIL : OK;
2797 /* Update the state if the rate is low or if we are being strict. If we
2798 are in leaky mode and the sender's rate is too high, we do not update
2799 the recorded rate in order to avoid an over-aggressive sender's retry
2800 rate preventing them from getting any email through. If readonly is set,
2801 neither leaky nor strict are set, so we do not do any updates. */
2803 if ((rc == FAIL && leaky) || strict)
2805 dbfn_write(dbm, key, dbdb, dbdb_size);
2806 HDEBUG(D_acl) debug_printf("ratelimit db updated\n");
2810 HDEBUG(D_acl) debug_printf("ratelimit db not updated: %s\n",
2811 readonly? "readonly mode" : "over the limit, but leaky");
2816 /* Store the result in the tree for future reference. */
2818 t = store_get(sizeof(tree_node) + Ustrlen(key));
2820 Ustrcpy(t->name, key);
2821 (void)tree_insertnode(anchor, t);
2823 /* We create the formatted version of the sender's rate very late in
2824 order to ensure that it is done using the correct storage pool. */
2826 store_pool = old_pool;
2827 sender_rate = string_sprintf("%.1f", dbd->rate);
2830 debug_printf("ratelimit computed rate %s\n", sender_rate);
2837 /*************************************************
2838 * The udpsend ACL modifier *
2839 *************************************************/
2841 /* Called by acl_check_condition() below.
2844 arg the option string for udpsend=
2845 log_msgptr for error messages
2847 Returns: OK - Completed.
2848 DEFER - Problem with DNS lookup.
2849 ERROR - Syntax error in options.
2853 acl_udpsend(uschar *arg, uschar **log_msgptr)
2865 hostname = string_nextinlist(&arg, &sep, NULL, 0);
2866 portstr = string_nextinlist(&arg, &sep, NULL, 0);
2868 if (hostname == NULL)
2870 *log_msgptr = US"missing destination host in \"udpsend\" modifier";
2873 if (portstr == NULL)
2875 *log_msgptr = US"missing destination port in \"udpsend\" modifier";
2880 *log_msgptr = US"missing datagram payload in \"udpsend\" modifier";
2883 portnum = Ustrtol(portstr, &portend, 10);
2884 if (*portend != '\0')
2886 *log_msgptr = US"bad destination port in \"udpsend\" modifier";
2890 /* Make a single-item host list. */
2891 h = store_get(sizeof(host_item));
2892 memset(h, 0, sizeof(host_item));
2897 if (string_is_ip_address(hostname, NULL))
2898 h->address = hostname, r = HOST_FOUND;
2900 r = host_find_byname(h, NULL, 0, NULL, FALSE);
2901 if (r == HOST_FIND_FAILED || r == HOST_FIND_AGAIN)
2903 *log_msgptr = US"DNS lookup failed in \"udpsend\" modifier";
2908 debug_printf("udpsend [%s]:%d %s\n", h->address, portnum, arg);
2910 r = s = ip_connectedsocket(SOCK_DGRAM, h->address, portnum, portnum,
2912 if (r < 0) goto defer;
2914 r = send(s, arg, len, 0);
2917 errstr = US strerror(errno);
2925 string_sprintf("\"udpsend\" truncated from %d to %d octets", len, r);
2930 debug_printf("udpsend %d bytes\n", r);
2935 *log_msgptr = string_sprintf("\"udpsend\" failed: %s", errstr);
2941 /*************************************************
2942 * Handle conditions/modifiers on an ACL item *
2943 *************************************************/
2945 /* Called from acl_check() below.
2949 cb ACL condition block - if NULL, result is OK
2950 where where called from
2951 addr the address being checked for RCPT, or NULL
2952 level the nesting level
2953 epp pointer to pass back TRUE if "endpass" encountered
2954 (applies only to "accept" and "discard")
2955 user_msgptr user message pointer
2956 log_msgptr log message pointer
2957 basic_errno pointer to where to put verify error
2959 Returns: OK - all conditions are met
2960 DISCARD - an "acl" condition returned DISCARD - only allowed
2961 for "accept" or "discard" verbs
2962 FAIL - at least one condition fails
2963 FAIL_DROP - an "acl" condition returned FAIL_DROP
2964 DEFER - can't tell at the moment (typically, lookup defer,
2965 but can be temporary callout problem)
2966 ERROR - ERROR from nested ACL or expansion failure or other
2971 acl_check_condition(int verb, acl_condition_block *cb, int where,
2972 address_item *addr, int level, BOOL *epp, uschar **user_msgptr,
2973 uschar **log_msgptr, int *basic_errno)
2975 uschar *user_message = NULL;
2976 uschar *log_message = NULL;
2977 uschar *debug_tag = NULL;
2978 uschar *debug_opts = NULL;
2981 #ifdef WITH_CONTENT_SCAN
2985 for (; cb != NULL; cb = cb->next)
2990 /* The message and log_message items set up messages to be used in
2991 case of rejection. They are expanded later. */
2993 if (cb->type == ACLC_MESSAGE)
2995 user_message = cb->arg;
2999 if (cb->type == ACLC_LOG_MESSAGE)
3001 log_message = cb->arg;
3005 /* The endpass "condition" just sets a flag to show it occurred. This is
3006 checked at compile time to be on an "accept" or "discard" item. */
3008 if (cb->type == ACLC_ENDPASS)
3014 /* For other conditions and modifiers, the argument is expanded now for some
3015 of them, but not for all, because expansion happens down in some lower level
3016 checking functions in some cases. */
3018 if (cond_expand_at_top[cb->type])
3020 arg = expand_string(cb->arg);
3023 if (expand_string_forcedfail) continue;
3024 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s",
3025 cb->arg, expand_string_message);
3026 return search_find_defer? DEFER : ERROR;
3031 /* Show condition, and expanded condition if it's different */
3036 debug_printf("check %s%s %n",
3037 (!cond_modifiers[cb->type] && cb->u.negated)? "!":"",
3038 conditions[cb->type], &lhswidth);
3040 if (cb->type == ACLC_SET)
3042 debug_printf("acl_%s ", cb->u.varname);
3043 lhswidth += 5 + Ustrlen(cb->u.varname);
3046 debug_printf("= %s\n", cb->arg);
3049 debug_printf("%.*s= %s\n", lhswidth,
3053 /* Check that this condition makes sense at this time */
3055 if ((cond_forbids[cb->type] & (1 << where)) != 0)
3057 *log_msgptr = string_sprintf("cannot %s %s condition in %s ACL",
3058 cond_modifiers[cb->type]? "use" : "test",
3059 conditions[cb->type], acl_wherenames[where]);
3063 /* Run the appropriate test for each condition, or take the appropriate
3064 action for the remaining modifiers. */
3068 case ACLC_ADD_HEADER:
3072 /* A nested ACL that returns "discard" makes sense only for an "accept" or
3076 rc = acl_check_wargs(where, addr, arg, level+1, user_msgptr, log_msgptr);
3077 if (rc == DISCARD && verb != ACL_ACCEPT && verb != ACL_DISCARD)
3079 *log_msgptr = string_sprintf("nested ACL returned \"discard\" for "
3080 "\"%s\" command (only allowed with \"accept\" or \"discard\")",
3086 case ACLC_AUTHENTICATED:
3087 rc = (sender_host_authenticated == NULL)? FAIL :
3088 match_isinlist(sender_host_authenticated, &arg, 0, NULL, NULL, MCL_STRING,
3092 #ifdef EXPERIMENTAL_BRIGHTMAIL
3093 case ACLC_BMI_OPTIN:
3095 int old_pool = store_pool;
3096 store_pool = POOL_PERM;
3097 bmi_current_optin = string_copy(arg);
3098 store_pool = old_pool;
3103 case ACLC_CONDITION:
3104 /* The true/false parsing here should be kept in sync with that used in
3105 expand.c when dealing with ECOND_BOOL so that we don't have too many
3106 different definitions of what can be a boolean. */
3108 ? Ustrspn(arg+1, "0123456789") == Ustrlen(arg+1) /* Negative number */
3109 : Ustrspn(arg, "0123456789") == Ustrlen(arg)) /* Digits, or empty */
3110 rc = (Uatoi(arg) == 0)? FAIL : OK;
3112 rc = (strcmpic(arg, US"no") == 0 ||
3113 strcmpic(arg, US"false") == 0)? FAIL :
3114 (strcmpic(arg, US"yes") == 0 ||
3115 strcmpic(arg, US"true") == 0)? OK : DEFER;
3117 *log_msgptr = string_sprintf("invalid \"condition\" value \"%s\"", arg);
3120 case ACLC_CONTINUE: /* Always succeeds */
3124 control_type = decode_control(arg, &p, where, log_msgptr);
3126 /* Check if this control makes sense at this time */
3128 if ((control_forbids[control_type] & (1 << where)) != 0)
3130 *log_msgptr = string_sprintf("cannot use \"control=%s\" in %s ACL",
3131 controls[control_type], acl_wherenames[where]);
3135 switch(control_type)
3137 case CONTROL_AUTH_UNADVERTISED:
3138 allow_auth_unadvertised = TRUE;
3141 #ifdef EXPERIMENTAL_BRIGHTMAIL
3142 case CONTROL_BMI_RUN:
3147 #ifndef DISABLE_DKIM
3148 case CONTROL_DKIM_VERIFY:
3149 dkim_disable_verify = TRUE;
3150 #ifdef EXPERIMENTAL_DMARC
3151 /* Since DKIM was blocked, skip DMARC too */
3152 dmarc_disable_verify = TRUE;
3153 dmarc_enable_forensic = FALSE;
3158 #ifdef EXPERIMENTAL_DMARC
3159 case CONTROL_DMARC_VERIFY:
3160 dmarc_disable_verify = TRUE;
3163 case CONTROL_DMARC_FORENSIC:
3164 dmarc_enable_forensic = TRUE;
3171 int fd, af, level, optname, value;
3172 /* If we are acting on stdin, the setsockopt may fail if stdin is not
3173 a socket; we can accept that, we'll just debug-log failures anyway. */
3174 fd = fileno(smtp_in);
3175 af = ip_get_address_family(fd);
3179 debug_printf("smtp input is probably not a socket [%s], not setting DSCP\n",
3183 if (dscp_lookup(p+1, af, &level, &optname, &value))
3185 if (setsockopt(fd, level, optname, &value, sizeof(value)) < 0)
3187 HDEBUG(D_acl) debug_printf("failed to set input DSCP[%s]: %s\n",
3188 p+1, strerror(errno));
3192 HDEBUG(D_acl) debug_printf("set input DSCP to \"%s\"\n", p+1);
3197 *log_msgptr = string_sprintf("unrecognised DSCP value in \"control=%s\"", arg);
3203 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3211 case CONTROL_CASEFUL_LOCAL_PART:
3212 deliver_localpart = addr->cc_local_part;
3215 case CONTROL_CASELOWER_LOCAL_PART:
3216 deliver_localpart = addr->lc_local_part;
3219 case CONTROL_ENFORCE_SYNC:
3220 smtp_enforce_sync = TRUE;
3223 case CONTROL_NO_ENFORCE_SYNC:
3224 smtp_enforce_sync = FALSE;
3227 #ifdef WITH_CONTENT_SCAN
3228 case CONTROL_NO_MBOX_UNSPOOL:
3229 no_mbox_unspool = TRUE;
3233 case CONTROL_NO_MULTILINE:
3234 no_multiline_responses = TRUE;
3237 case CONTROL_NO_PIPELINING:
3238 pipelining_enable = FALSE;
3241 case CONTROL_NO_DELAY_FLUSH:
3242 disable_delay_flush = TRUE;
3245 case CONTROL_NO_CALLOUT_FLUSH:
3246 disable_callout_flush = TRUE;
3249 case CONTROL_FAKEDEFER:
3250 case CONTROL_FAKEREJECT:
3251 fake_response = (control_type == CONTROL_FAKEDEFER) ? DEFER : FAIL;
3255 while (*pp != 0) pp++;
3256 fake_response_text = expand_string(string_copyn(p+1, pp-p-1));
3261 /* Explicitly reset to default string */
3262 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).";
3266 case CONTROL_FREEZE:
3267 deliver_freeze = TRUE;
3268 deliver_frozen_at = time(NULL);
3269 freeze_tell = freeze_tell_config; /* Reset to configured value */
3270 if (Ustrncmp(p, "/no_tell", 8) == 0)
3277 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3282 case CONTROL_QUEUE_ONLY:
3283 queue_only_policy = TRUE;
3286 case CONTROL_SUBMISSION:
3287 originator_name = US"";
3288 submission_mode = TRUE;
3291 if (Ustrncmp(p, "/sender_retain", 14) == 0)
3294 active_local_sender_retain = TRUE;
3295 active_local_from_check = FALSE;
3297 else if (Ustrncmp(p, "/domain=", 8) == 0)
3300 while (*pp != 0 && *pp != '/') pp++;
3301 submission_domain = string_copyn(p+8, pp-p-8);
3304 /* The name= option must be last, because it swallows the rest of
3306 else if (Ustrncmp(p, "/name=", 6) == 0)
3309 while (*pp != 0) pp++;
3310 submission_name = string_copy(parse_fix_phrase(p+6, pp-p-6,
3311 big_buffer, big_buffer_size));
3318 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3326 if (Ustrncmp(p, "/tag=", 5) == 0)
3329 while (*pp != '\0' && *pp != '/') pp++;
3330 debug_tag = string_copyn(p+5, pp-p-5);
3333 else if (Ustrncmp(p, "/opts=", 6) == 0)
3336 while (*pp != '\0' && *pp != '/') pp++;
3337 debug_opts = string_copyn(p+6, pp-p-6);
3341 debug_logging_activate(debug_tag, debug_opts);
3344 case CONTROL_SUPPRESS_LOCAL_FIXUPS:
3345 suppress_local_fixups = TRUE;
3348 case CONTROL_CUTTHROUGH_DELIVERY:
3351 *log_msgptr = string_sprintf("\"control=%s\" on frozen item", arg);
3354 if (queue_only_policy)
3356 *log_msgptr = string_sprintf("\"control=%s\" on queue-only item", arg);
3359 cutthrough_delivery = TRUE;
3364 #ifdef EXPERIMENTAL_DCC
3367 /* Seperate the regular expression and any optional parameters. */
3368 uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size);
3369 /* Run the dcc backend. */
3370 rc = dcc_process(&ss);
3371 /* Modify return code based upon the existance of options. */
3372 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
3374 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
3376 /* FAIL so that the message is passed to the next ACL */
3384 #ifdef WITH_CONTENT_SCAN
3386 rc = mime_decode(&arg);
3392 int delay = readconf_readtime(arg, 0, FALSE);
3395 *log_msgptr = string_sprintf("syntax error in argument for \"delay\" "
3396 "modifier: \"%s\" is not a time value", arg);
3401 HDEBUG(D_acl) debug_printf("delay modifier requests %d-second delay\n",
3406 debug_printf("delay skipped in -bh checking mode\n");
3409 /* It appears to be impossible to detect that a TCP/IP connection has
3410 gone away without reading from it. This means that we cannot shorten
3411 the delay below if the client goes away, because we cannot discover
3412 that the client has closed its end of the connection. (The connection
3413 is actually in a half-closed state, waiting for the server to close its
3414 end.) It would be nice to be able to detect this state, so that the
3415 Exim process is not held up unnecessarily. However, it seems that we
3416 can't. The poll() function does not do the right thing, and in any case
3417 it is not always available.
3419 NOTE 1: If ever this state of affairs changes, remember that we may be
3420 dealing with stdin/stdout here, in addition to TCP/IP connections.
3421 Also, delays may be specified for non-SMTP input, where smtp_out and
3422 smtp_in will be NULL. Whatever is done must work in all cases.
3424 NOTE 2: The added feature of flushing the output before a delay must
3425 apply only to SMTP input. Hence the test for smtp_out being non-NULL.
3430 if (smtp_out != NULL && !disable_delay_flush) mac_smtp_fflush();
3431 while (delay > 0) delay = sleep(delay);
3437 #ifdef WITH_OLD_DEMIME
3443 #ifndef DISABLE_DKIM
3444 case ACLC_DKIM_SIGNER:
3445 if (dkim_cur_signer != NULL)
3446 rc = match_isinlist(dkim_cur_signer,
3447 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
3452 case ACLC_DKIM_STATUS:
3453 rc = match_isinlist(dkim_exim_expand_query(DKIM_VERIFY_STATUS),
3454 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
3458 #ifdef EXPERIMENTAL_DMARC
3459 case ACLC_DMARC_STATUS:
3460 if (!dmarc_has_been_checked)
3462 dmarc_has_been_checked = TRUE;
3463 /* used long way of dmarc_exim_expand_query() in case we need more
3464 * view into the process in the future. */
3465 rc = match_isinlist(dmarc_exim_expand_query(DMARC_VERIFY_STATUS),
3466 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
3471 rc = verify_check_dnsbl(&arg);
3475 rc = match_isinlist(addr->domain, &arg, 0, &domainlist_anchor,
3476 addr->domain_cache, MCL_DOMAIN, TRUE, &deliver_domain_data);
3479 /* The value in tls_cipher is the full cipher name, for example,
3480 TLSv1:DES-CBC3-SHA:168, whereas the values to test for are just the
3481 cipher names such as DES-CBC3-SHA. But program defensively. We don't know
3482 what may in practice come out of the SSL library - which at the time of
3483 writing is poorly documented. */
3485 case ACLC_ENCRYPTED:
3486 if (tls_in.cipher == NULL) rc = FAIL; else
3488 uschar *endcipher = NULL;
3489 uschar *cipher = Ustrchr(tls_in.cipher, ':');
3490 if (cipher == NULL) cipher = tls_in.cipher; else
3492 endcipher = Ustrchr(++cipher, ':');
3493 if (endcipher != NULL) *endcipher = 0;
3495 rc = match_isinlist(cipher, &arg, 0, NULL, NULL, MCL_STRING, TRUE, NULL);
3496 if (endcipher != NULL) *endcipher = ':';
3500 /* Use verify_check_this_host() instead of verify_check_host() so that
3501 we can pass over &host_data to catch any looked up data. Once it has been
3502 set, it retains its value so that it's still there if another ACL verb
3503 comes through here and uses the cache. However, we must put it into
3504 permanent store in case it is also expected to be used in a subsequent
3505 message in the same SMTP connection. */
3508 rc = verify_check_this_host(&arg, sender_host_cache, NULL,
3509 (sender_host_address == NULL)? US"" : sender_host_address, &host_data);
3510 if (host_data != NULL) host_data = string_copy_malloc(host_data);
3513 case ACLC_LOCAL_PARTS:
3514 rc = match_isinlist(addr->cc_local_part, &arg, 0,
3515 &localpartlist_anchor, addr->localpart_cache, MCL_LOCALPART, TRUE,
3516 &deliver_localpart_data);
3519 case ACLC_LOG_REJECT_TARGET:
3525 while ((ss = string_nextinlist(&s, &sep, big_buffer, big_buffer_size))
3528 if (Ustrcmp(ss, "main") == 0) logbits |= LOG_MAIN;
3529 else if (Ustrcmp(ss, "panic") == 0) logbits |= LOG_PANIC;
3530 else if (Ustrcmp(ss, "reject") == 0) logbits |= LOG_REJECT;
3533 logbits |= LOG_MAIN|LOG_REJECT;
3534 log_write(0, LOG_MAIN|LOG_PANIC, "unknown log name \"%s\" in "
3535 "\"log_reject_target\" in %s ACL", ss, acl_wherenames[where]);
3538 log_reject_target = logbits;
3551 if (Ustrncmp(s, "main", 4) == 0)
3552 { logbits |= LOG_MAIN; s += 4; }
3553 else if (Ustrncmp(s, "panic", 5) == 0)
3554 { logbits |= LOG_PANIC; s += 5; }
3555 else if (Ustrncmp(s, "reject", 6) == 0)
3556 { logbits |= LOG_REJECT; s += 6; }
3559 logbits = LOG_MAIN|LOG_PANIC;
3560 s = string_sprintf(":unknown log name in \"%s\" in "
3561 "\"logwrite\" in %s ACL", arg, acl_wherenames[where]);
3567 while (isspace(*s)) s++;
3570 if (logbits == 0) logbits = LOG_MAIN;
3571 log_write(0, logbits, "%s", string_printing(s));
3575 #ifdef WITH_CONTENT_SCAN
3578 /* Separate the regular expression and any optional parameters. */
3579 uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size);
3580 /* Run the malware backend. */
3582 /* Modify return code based upon the existance of options. */
3583 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
3585 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
3587 /* FAIL so that the message is passed to the next ACL */
3594 case ACLC_MIME_REGEX:
3595 rc = mime_regex(&arg);
3599 case ACLC_RATELIMIT:
3600 rc = acl_ratelimit(arg, where, log_msgptr);
3603 case ACLC_RECIPIENTS:
3604 rc = match_address_list(addr->address, TRUE, TRUE, &arg, NULL, -1, 0,
3608 #ifdef WITH_CONTENT_SCAN
3614 case ACLC_REMOVE_HEADER:
3615 setup_remove_header(arg);
3618 case ACLC_SENDER_DOMAINS:
3621 sdomain = Ustrrchr(sender_address, '@');
3622 sdomain = (sdomain == NULL)? US"" : sdomain + 1;
3623 rc = match_isinlist(sdomain, &arg, 0, &domainlist_anchor,
3624 sender_domain_cache, MCL_DOMAIN, TRUE, NULL);
3629 rc = match_address_list(sender_address, TRUE, TRUE, &arg,
3630 sender_address_cache, -1, 0, &sender_data);
3633 /* Connection variables must persist forever */
3637 int old_pool = store_pool;
3638 if (cb->u.varname[0] == 'c') store_pool = POOL_PERM;
3639 acl_var_create(cb->u.varname)->data.ptr = string_copy(arg);
3640 store_pool = old_pool;
3644 #ifdef WITH_CONTENT_SCAN
3647 /* Seperate the regular expression and any optional parameters. */
3648 uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size);
3649 /* Run the spam backend. */
3651 /* Modify return code based upon the existance of options. */
3652 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
3654 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
3656 /* FAIL so that the message is passed to the next ACL */
3664 #ifdef EXPERIMENTAL_SPF
3666 rc = spf_process(&arg, sender_address, SPF_PROCESS_NORMAL);
3668 case ACLC_SPF_GUESS:
3669 rc = spf_process(&arg, sender_address, SPF_PROCESS_GUESS);
3674 rc = acl_udpsend(arg, log_msgptr);
3677 /* If the verb is WARN, discard any user message from verification, because
3678 such messages are SMTP responses, not header additions. The latter come
3679 only from explicit "message" modifiers. However, put the user message into
3680 $acl_verify_message so it can be used in subsequent conditions or modifiers
3681 (until something changes it). */
3684 rc = acl_verify(where, addr, arg, user_msgptr, log_msgptr, basic_errno);
3685 acl_verify_message = *user_msgptr;
3686 if (verb == ACL_WARN) *user_msgptr = NULL;
3690 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown "
3691 "condition %d", cb->type);
3695 /* If a condition was negated, invert OK/FAIL. */
3697 if (!cond_modifiers[cb->type] && cb->u.negated)
3699 if (rc == OK) rc = FAIL;
3700 else if (rc == FAIL || rc == FAIL_DROP) rc = OK;
3703 if (rc != OK) break; /* Conditions loop */
3707 /* If the result is the one for which "message" and/or "log_message" are used,
3708 handle the values of these modifiers. If there isn't a log message set, we make
3709 it the same as the user message.
3711 "message" is a user message that will be included in an SMTP response. Unless
3712 it is empty, it overrides any previously set user message.
3714 "log_message" is a non-user message, and it adds to any existing non-user
3715 message that is already set.
3717 Most verbs have but a single return for which the messages are relevant, but
3718 for "discard", it's useful to have the log message both when it succeeds and
3719 when it fails. For "accept", the message is used in the OK case if there is no
3720 "endpass", but (for backwards compatibility) in the FAIL case if "endpass" is
3723 if (*epp && rc == OK) user_message = NULL;
3725 if (((1<<rc) & msgcond[verb]) != 0)
3728 uschar *old_user_msgptr = *user_msgptr;
3729 uschar *old_log_msgptr = (*log_msgptr != NULL)? *log_msgptr : old_user_msgptr;
3731 /* If the verb is "warn", messages generated by conditions (verification or
3732 nested ACLs) are always discarded. This also happens for acceptance verbs
3733 when they actually do accept. Only messages specified at this level are used.
3734 However, the value of an existing message is available in $acl_verify_message
3735 during expansions. */
3737 if (verb == ACL_WARN ||
3738 (rc == OK && (verb == ACL_ACCEPT || verb == ACL_DISCARD)))
3739 *log_msgptr = *user_msgptr = NULL;
3741 if (user_message != NULL)
3743 acl_verify_message = old_user_msgptr;
3744 expmessage = expand_string(user_message);
3745 if (expmessage == NULL)
3747 if (!expand_string_forcedfail)
3748 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
3749 user_message, expand_string_message);
3751 else if (expmessage[0] != 0) *user_msgptr = expmessage;
3754 if (log_message != NULL)
3756 acl_verify_message = old_log_msgptr;
3757 expmessage = expand_string(log_message);
3758 if (expmessage == NULL)
3760 if (!expand_string_forcedfail)
3761 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
3762 log_message, expand_string_message);
3764 else if (expmessage[0] != 0)
3766 *log_msgptr = (*log_msgptr == NULL)? expmessage :
3767 string_sprintf("%s: %s", expmessage, *log_msgptr);
3771 /* If no log message, default it to the user message */
3773 if (*log_msgptr == NULL) *log_msgptr = *user_msgptr;
3776 acl_verify_message = NULL;
3784 /*************************************************
3785 * Get line from a literal ACL *
3786 *************************************************/
3788 /* This function is passed to acl_read() in order to extract individual lines
3789 of a literal ACL, which we access via static pointers. We can destroy the
3790 contents because this is called only once (the compiled ACL is remembered).
3792 This code is intended to treat the data in the same way as lines in the main
3793 Exim configuration file. That is:
3795 . Leading spaces are ignored.
3797 . A \ at the end of a line is a continuation - trailing spaces after the \
3798 are permitted (this is because I don't believe in making invisible things
3799 significant). Leading spaces on the continued part of a line are ignored.
3801 . Physical lines starting (significantly) with # are totally ignored, and
3802 may appear within a sequence of backslash-continued lines.
3804 . Blank lines are ignored, but will end a sequence of continuations.
3807 Returns: a pointer to the next line
3811 static uschar *acl_text; /* Current pointer in the text */
3812 static uschar *acl_text_end; /* Points one past the terminating '0' */
3820 /* This loop handles leading blank lines and comments. */
3824 while (isspace(*acl_text)) acl_text++; /* Leading spaces/empty lines */
3825 if (*acl_text == 0) return NULL; /* No more data */
3826 yield = acl_text; /* Potential data line */
3828 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3830 /* If we hit the end before a newline, we have the whole logical line. If
3831 it's a comment, there's no more data to be given. Otherwise, yield it. */
3833 if (*acl_text == 0) return (*yield == '#')? NULL : yield;
3835 /* After reaching a newline, end this loop if the physical line does not
3836 start with '#'. If it does, it's a comment, and the loop continues. */
3838 if (*yield != '#') break;
3841 /* This loop handles continuations. We know we have some real data, ending in
3842 newline. See if there is a continuation marker at the end (ignoring trailing
3843 white space). We know that *yield is not white space, so no need to test for
3844 cont > yield in the backwards scanning loop. */
3849 for (cont = acl_text - 1; isspace(*cont); cont--);
3851 /* If no continuation follows, we are done. Mark the end of the line and
3860 /* We have encountered a continuation. Skip over whitespace at the start of
3861 the next line, and indeed the whole of the next line or lines if they are
3866 while (*(++acl_text) == ' ' || *acl_text == '\t');
3867 if (*acl_text != '#') break;
3868 while (*(++acl_text) != 0 && *acl_text != '\n');
3871 /* We have the start of a continuation line. Move all the rest of the data
3872 to join onto the previous line, and then find its end. If the end is not a
3873 newline, we are done. Otherwise loop to look for another continuation. */
3875 memmove(cont, acl_text, acl_text_end - acl_text);
3876 acl_text_end -= acl_text - cont;
3878 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3879 if (*acl_text == 0) return yield;
3882 /* Control does not reach here */
3889 /*************************************************
3890 * Check access using an ACL *
3891 *************************************************/
3893 /* This function is called from address_check. It may recurse via
3894 acl_check_condition() - hence the use of a level to stop looping. The ACL is
3895 passed as a string which is expanded. A forced failure implies no access check
3896 is required. If the result is a single word, it is taken as the name of an ACL
3897 which is sought in the global ACL tree. Otherwise, it is taken as literal ACL
3898 text, complete with newlines, and parsed as such. In both cases, the ACL check
3899 is then run. This function uses an auxiliary function for acl_read() to call
3900 for reading individual lines of a literal ACL. This is acl_getline(), which
3901 appears immediately above.
3904 where where called from
3905 addr address item when called from RCPT; otherwise NULL
3906 s the input string; NULL is the same as an empty ACL => DENY
3907 level the nesting level
3908 user_msgptr where to put a user error (for SMTP response)
3909 log_msgptr where to put a logging message (not for SMTP response)
3911 Returns: OK access is granted
3912 DISCARD access is apparently granted...
3913 FAIL access is denied
3914 FAIL_DROP access is denied; drop the connection
3915 DEFER can't tell at the moment
3920 acl_check_internal(int where, address_item *addr, uschar *s, int level,
3921 uschar **user_msgptr, uschar **log_msgptr)
3924 acl_block *acl = NULL;
3925 uschar *acl_name = US"inline ACL";
3928 /* Catch configuration loops */
3932 *log_msgptr = US"ACL nested too deep: possible loop";
3938 HDEBUG(D_acl) debug_printf("ACL is NULL: implicit DENY\n");
3942 /* At top level, we expand the incoming string. At lower levels, it has already
3943 been expanded as part of condition processing. */
3947 ss = expand_string(s);
3950 if (expand_string_forcedfail) return OK;
3951 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s", s,
3952 expand_string_message);
3958 while (isspace(*ss))ss++;
3960 /* If we can't find a named ACL, the default is to parse it as an inline one.
3961 (Unless it begins with a slash; non-existent files give rise to an error.) */
3965 /* Handle the case of a string that does not contain any spaces. Look for a
3966 named ACL among those read from the configuration, or a previously read file.
3967 It is possible that the pointer to the ACL is NULL if the configuration
3968 contains a name with no data. If not found, and the text begins with '/',
3969 read an ACL from a file, and save it so it can be re-used. */
3971 if (Ustrchr(ss, ' ') == NULL)
3973 tree_node *t = tree_search(acl_anchor, ss);
3976 acl = (acl_block *)(t->data.ptr);
3979 HDEBUG(D_acl) debug_printf("ACL \"%s\" is empty: implicit DENY\n", ss);
3982 acl_name = string_sprintf("ACL \"%s\"", ss);
3983 HDEBUG(D_acl) debug_printf("using ACL \"%s\"\n", ss);
3986 else if (*ss == '/')
3988 struct stat statbuf;
3989 fd = Uopen(ss, O_RDONLY, 0);
3992 *log_msgptr = string_sprintf("failed to open ACL file \"%s\": %s", ss,
3997 if (fstat(fd, &statbuf) != 0)
3999 *log_msgptr = string_sprintf("failed to fstat ACL file \"%s\": %s", ss,
4004 acl_text = store_get(statbuf.st_size + 1);
4005 acl_text_end = acl_text + statbuf.st_size + 1;
4007 if (read(fd, acl_text, statbuf.st_size) != statbuf.st_size)
4009 *log_msgptr = string_sprintf("failed to read ACL file \"%s\": %s",
4010 ss, strerror(errno));
4013 acl_text[statbuf.st_size] = 0;
4016 acl_name = string_sprintf("ACL \"%s\"", ss);
4017 HDEBUG(D_acl) debug_printf("read ACL from file %s\n", ss);
4021 /* Parse an ACL that is still in text form. If it came from a file, remember it
4022 in the ACL tree, having read it into the POOL_PERM store pool so that it
4023 persists between multiple messages. */
4027 int old_pool = store_pool;
4028 if (fd >= 0) store_pool = POOL_PERM;
4029 acl = acl_read(acl_getline, log_msgptr);
4030 store_pool = old_pool;
4031 if (acl == NULL && *log_msgptr != NULL) return ERROR;
4034 tree_node *t = store_get_perm(sizeof(tree_node) + Ustrlen(ss));
4035 Ustrcpy(t->name, ss);
4037 (void)tree_insertnode(&acl_anchor, t);
4041 /* Now we have an ACL to use. It's possible it may be NULL. */
4046 int basic_errno = 0;
4047 BOOL endpass_seen = FALSE;
4049 *log_msgptr = *user_msgptr = NULL;
4050 acl_temp_details = FALSE;
4052 if ((where == ACL_WHERE_QUIT || where == ACL_WHERE_NOTQUIT) &&
4053 acl->verb != ACL_ACCEPT &&
4054 acl->verb != ACL_WARN)
4056 *log_msgptr = string_sprintf("\"%s\" is not allowed in a QUIT or not-QUIT ACL",
4061 HDEBUG(D_acl) debug_printf("processing \"%s\"\n", verbs[acl->verb]);
4063 /* Clear out any search error message from a previous check before testing
4066 search_error_message = NULL;
4067 cond = acl_check_condition(acl->verb, acl->condition, where, addr, level,
4068 &endpass_seen, user_msgptr, log_msgptr, &basic_errno);
4070 /* Handle special returns: DEFER causes a return except on a WARN verb;
4071 ERROR always causes a return. */
4076 HDEBUG(D_acl) debug_printf("%s: condition test deferred in %s\n", verbs[acl->verb], acl_name);
4077 if (basic_errno != ERRNO_CALLOUTDEFER)
4079 if (search_error_message != NULL && *search_error_message != 0)
4080 *log_msgptr = search_error_message;
4081 if (smtp_return_error_details) acl_temp_details = TRUE;
4085 acl_temp_details = TRUE;
4087 if (acl->verb != ACL_WARN) return DEFER;
4090 default: /* Paranoia */
4092 HDEBUG(D_acl) debug_printf("%s: condition test error in %s\n", verbs[acl->verb], acl_name);
4096 HDEBUG(D_acl) debug_printf("%s: condition test succeeded in %s\n",
4097 verbs[acl->verb], acl_name);
4101 HDEBUG(D_acl) debug_printf("%s: condition test failed in %s\n", verbs[acl->verb], acl_name);
4104 /* DISCARD and DROP can happen only from a nested ACL condition, and
4105 DISCARD can happen only for an "accept" or "discard" verb. */
4108 HDEBUG(D_acl) debug_printf("%s: condition test yielded \"discard\" in %s\n",
4109 verbs[acl->verb], acl_name);
4113 HDEBUG(D_acl) debug_printf("%s: condition test yielded \"drop\" in %s\n",
4114 verbs[acl->verb], acl_name);
4118 /* At this point, cond for most verbs is either OK or FAIL or (as a result of
4119 a nested ACL condition) FAIL_DROP. However, for WARN, cond may be DEFER, and
4120 for ACCEPT and DISCARD, it may be DISCARD after a nested ACL call. */
4125 if (cond == OK || cond == DISCARD) return cond;
4128 HDEBUG(D_acl) debug_printf("accept: endpass encountered - denying access\n");
4136 acl_temp_details = TRUE;
4142 if (cond == OK) return FAIL;
4146 if (cond == OK || cond == DISCARD) return DISCARD;
4149 HDEBUG(D_acl) debug_printf("discard: endpass encountered - denying access\n");
4155 if (cond == OK) return FAIL_DROP;
4159 if (cond != OK) return cond;
4164 acl_warn(where, *user_msgptr, *log_msgptr);
4165 else if (cond == DEFER && (log_extra_selector & LX_acl_warn_skipped) != 0)
4166 log_write(0, LOG_MAIN, "%s Warning: ACL \"warn\" statement skipped: "
4167 "condition test deferred%s%s", host_and_ident(TRUE),
4168 (*log_msgptr == NULL)? US"" : US": ",
4169 (*log_msgptr == NULL)? US"" : *log_msgptr);
4170 *log_msgptr = *user_msgptr = NULL; /* In case implicit DENY follows */
4174 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown verb %d",
4179 /* Pass to the next ACL item */
4184 /* We have reached the end of the ACL. This is an implicit DENY. */
4186 HDEBUG(D_acl) debug_printf("end of %s: implicit DENY\n", acl_name);
4193 /* Same args as acl_check_internal() above, but the string s is
4194 the name of an ACL followed optionally by up to 9 space-separated arguments.
4195 The name and args are separately expanded. Args go into $acl_arg globals. */
4197 acl_check_wargs(int where, address_item *addr, uschar *s, int level,
4198 uschar **user_msgptr, uschar **log_msgptr)
4201 uschar * tmp_arg[9]; /* must match acl_arg[] */
4202 uschar * sav_arg[9]; /* must match acl_arg[] */
4208 if (!(tmp = string_dequote(&s)) || !(name = expand_string(tmp)))
4211 for (i = 0; i < 9; i++)
4213 while (*s && isspace(*s)) s++;
4215 if (!(tmp = string_dequote(&s)) || !(tmp_arg[i] = expand_string(tmp)))
4222 sav_narg = acl_narg;
4224 for (i = 0; i < acl_narg; i++)
4226 sav_arg[i] = acl_arg[i];
4227 acl_arg[i] = tmp_arg[i];
4231 sav_arg[i] = acl_arg[i];
4232 acl_arg[i++] = NULL;
4235 ret = acl_check_internal(where, addr, name, level, user_msgptr, log_msgptr);
4237 acl_narg = sav_narg;
4238 for (i = 0; i < 9; i++) acl_arg[i] = sav_arg[i];
4242 if (expand_string_forcedfail) return ERROR;
4243 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s",
4244 tmp, expand_string_message);
4245 return search_find_defer?DEFER:ERROR;
4250 /*************************************************
4251 * Check access using an ACL *
4252 *************************************************/
4254 /* Alternate interface for ACL, used by expansions */
4256 acl_eval(int where, uschar *s, uschar **user_msgptr, uschar **log_msgptr)
4259 address_item *addr = NULL;
4261 *user_msgptr = *log_msgptr = NULL;
4262 sender_verified_failed = NULL;
4263 ratelimiters_cmd = NULL;
4264 log_reject_target = LOG_MAIN|LOG_REJECT;
4266 if (where == ACL_WHERE_RCPT)
4268 adb = address_defaults;
4270 addr->address = expand_string(US"$local_part@$domain");
4271 addr->domain = deliver_domain;
4272 addr->local_part = deliver_localpart;
4273 addr->cc_local_part = deliver_localpart;
4274 addr->lc_local_part = deliver_localpart;
4277 return acl_check_internal(where, addr, s, 0, user_msgptr, log_msgptr);
4282 /* This is the external interface for ACL checks. It sets up an address and the
4283 expansions for $domain and $local_part when called after RCPT, then calls
4284 acl_check_internal() to do the actual work.
4287 where ACL_WHERE_xxxx indicating where called from
4288 recipient RCPT address for RCPT check, else NULL
4289 s the input string; NULL is the same as an empty ACL => DENY
4290 user_msgptr where to put a user error (for SMTP response)
4291 log_msgptr where to put a logging message (not for SMTP response)
4293 Returns: OK access is granted by an ACCEPT verb
4294 DISCARD access is granted by a DISCARD verb
4295 FAIL access is denied
4296 FAIL_DROP access is denied; drop the connection
4297 DEFER can't tell at the moment
4300 int acl_where = ACL_WHERE_UNKNOWN;
4303 acl_check(int where, uschar *recipient, uschar *s, uschar **user_msgptr,
4304 uschar **log_msgptr)
4308 address_item *addr = NULL;
4310 *user_msgptr = *log_msgptr = NULL;
4311 sender_verified_failed = NULL;
4312 ratelimiters_cmd = NULL;
4313 log_reject_target = LOG_MAIN|LOG_REJECT;
4315 #ifdef EXPERIMENTAL_PRDR
4316 if (where == ACL_WHERE_RCPT || where == ACL_WHERE_PRDR )
4318 if (where == ACL_WHERE_RCPT )
4321 adb = address_defaults;
4323 addr->address = recipient;
4324 if (deliver_split_address(addr) == DEFER)
4326 *log_msgptr = US"defer in percent_hack_domains check";
4329 deliver_domain = addr->domain;
4330 deliver_localpart = addr->local_part;
4334 rc = acl_check_internal(where, addr, s, 0, user_msgptr, log_msgptr);
4335 acl_where = ACL_WHERE_UNKNOWN;
4337 /* Cutthrough - if requested,
4338 and WHERE_RCPT and not yet opened conn as result of recipient-verify,
4339 and rcpt acl returned accept,
4340 and first recipient (cancel on any subsequents)
4341 open one now and run it up to RCPT acceptance.
4342 A failed verify should cancel cutthrough request.
4344 Initial implementation: dual-write to spool.
4345 Assume the rxd datastream is now being copied byte-for-byte to an open cutthrough connection.
4347 Cease cutthrough copy on rxd final dot; do not send one.
4349 On a data acl, if not accept and a cutthrough conn is open, hard-close it (no SMTP niceness).
4351 On data acl accept, terminate the dataphase on an open cutthrough conn. If accepted or
4352 perm-rejected, reflect that to the original sender - and dump the spooled copy.
4353 If temp-reject, close the conn (and keep the spooled copy).
4354 If conn-failure, no action (and keep the spooled copy).
4358 case ACL_WHERE_RCPT:
4359 #ifdef EXPERIMENTAL_PRDR
4360 case ACL_WHERE_PRDR:
4362 if( rcpt_count > 1 )
4363 cancel_cutthrough_connection("more than one recipient");
4364 else if (rc == OK && cutthrough_delivery && cutthrough_fd < 0)
4365 open_cutthrough_connection(addr);
4368 case ACL_WHERE_PREDATA:
4370 cutthrough_predata();
4372 cancel_cutthrough_connection("predata acl not ok");
4375 case ACL_WHERE_QUIT:
4376 case ACL_WHERE_NOTQUIT:
4377 cancel_cutthrough_connection("quit or notquit");
4384 deliver_domain = deliver_localpart = deliver_address_data =
4385 sender_address_data = NULL;
4387 /* A DISCARD response is permitted only for message ACLs, excluding the PREDATA
4388 ACL, which is really in the middle of an SMTP command. */
4392 if (where > ACL_WHERE_NOTSMTP || where == ACL_WHERE_PREDATA)
4394 log_write(0, LOG_MAIN|LOG_PANIC, "\"discard\" verb not allowed in %s "
4395 "ACL", acl_wherenames[where]);
4401 /* A DROP response is not permitted from MAILAUTH */
4403 if (rc == FAIL_DROP && where == ACL_WHERE_MAILAUTH)
4405 log_write(0, LOG_MAIN|LOG_PANIC, "\"drop\" verb not allowed in %s "
4406 "ACL", acl_wherenames[where]);
4410 /* Before giving a response, take a look at the length of any user message, and
4411 split it up into multiple lines if possible. */
4413 *user_msgptr = string_split_message(*user_msgptr);
4414 if (fake_response != OK)
4415 fake_response_text = string_split_message(fake_response_text);
4421 /*************************************************
4422 * Create ACL variable *
4423 *************************************************/
4425 /* Create an ACL variable or reuse an existing one. ACL variables are in a
4426 binary tree (see tree.c) with acl_var_c and acl_var_m as root nodes.
4429 name pointer to the variable's name, starting with c or m
4431 Returns the pointer to variable's tree node
4435 acl_var_create(uschar *name)
4437 tree_node *node, **root;
4438 root = (name[0] == 'c')? &acl_var_c : &acl_var_m;
4439 node = tree_search(*root, name);
4442 node = store_get(sizeof(tree_node) + Ustrlen(name));
4443 Ustrcpy(node->name, name);
4444 (void)tree_insertnode(root, node);
4446 node->data.ptr = NULL;
4452 /*************************************************
4453 * Write an ACL variable in spool format *
4454 *************************************************/
4456 /* This function is used as a callback for tree_walk when writing variables to
4457 the spool file. To retain spool file compatibility, what is written is -aclc or
4458 -aclm followed by the rest of the name and the data length, space separated,
4459 then the value itself, starting on a new line, and terminated by an additional
4460 newline. When we had only numbered ACL variables, the first line might look
4461 like this: "-aclc 5 20". Now it might be "-aclc foo 20" for the variable called
4465 name of the variable
4466 value of the variable
4467 ctx FILE pointer (as a void pointer)
4473 acl_var_write(uschar *name, uschar *value, void *ctx)
4475 FILE *f = (FILE *)ctx;
4476 fprintf(f, "-acl%c %s %d\n%s\n", name[0], name+1, Ustrlen(value), value);