1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2012 */
6 /* See the file NOTICE for conditions of use and distribution. */
8 /* Code for handling Access Control Lists (ACLs) */
13 /* Default callout timeout */
15 #define CALLOUT_TIMEOUT_DEFAULT 30
17 /* ACL verb codes - keep in step with the table of verbs that follows */
19 enum { ACL_ACCEPT, ACL_DEFER, ACL_DENY, ACL_DISCARD, ACL_DROP, ACL_REQUIRE,
24 static uschar *verbs[] = {
33 /* For each verb, the conditions for which "message" or "log_message" are used
34 are held as a bitmap. This is to avoid expanding the strings unnecessarily. For
35 "accept", the FAIL case is used only after "endpass", but that is selected in
38 static int msgcond[] = {
39 (1<<OK) | (1<<FAIL) | (1<<FAIL_DROP), /* accept */
42 (1<<OK) | (1<<FAIL) | (1<<FAIL_DROP), /* discard */
44 (1<<FAIL) | (1<<FAIL_DROP), /* require */
48 /* ACL condition and modifier codes - keep in step with the table that
49 follows, and the cond_expand_at_top and uschar cond_modifiers tables lower
55 #ifdef EXPERIMENTAL_BRIGHTMAIL
61 #ifdef EXPERIMENTAL_DCC
64 #ifdef WITH_CONTENT_SCAN
68 #ifdef WITH_OLD_DEMIME
75 #ifdef EXPERIMENTAL_DMARC
85 ACLC_LOG_REJECT_TARGET,
87 #ifdef WITH_CONTENT_SCAN
91 #ifdef WITH_CONTENT_SCAN
96 #ifdef WITH_CONTENT_SCAN
103 #ifdef WITH_CONTENT_SCAN
106 #ifdef EXPERIMENTAL_SPF
113 /* ACL conditions/modifiers: "delay", "control", "continue", "endpass",
114 "message", "log_message", "log_reject_target", "logwrite", and "set" are
115 modifiers that look like conditions but always return TRUE. They are used for
116 their side effects. */
118 static uschar *conditions[] = {
122 #ifdef EXPERIMENTAL_BRIGHTMAIL
128 #ifdef EXPERIMENTAL_DCC
131 #ifdef WITH_CONTENT_SCAN
135 #ifdef WITH_OLD_DEMIME
142 #ifdef EXPERIMENTAL_DMARC
152 US"log_reject_target",
154 #ifdef WITH_CONTENT_SCAN
158 #ifdef WITH_CONTENT_SCAN
163 #ifdef WITH_CONTENT_SCAN
167 US"sender_domains", US"senders", US"set",
168 #ifdef WITH_CONTENT_SCAN
171 #ifdef EXPERIMENTAL_SPF
179 /* Return values from decode_control(); keep in step with the table of names
183 CONTROL_AUTH_UNADVERTISED,
184 #ifdef EXPERIMENTAL_BRIGHTMAIL
191 #ifdef EXPERIMENTAL_DMARC
192 CONTROL_DMARC_VERIFY,
193 CONTROL_DMARC_FORENSIC,
197 CONTROL_CASEFUL_LOCAL_PART,
198 CONTROL_CASELOWER_LOCAL_PART,
199 CONTROL_CUTTHROUGH_DELIVERY,
200 CONTROL_ENFORCE_SYNC,
201 CONTROL_NO_ENFORCE_SYNC,
205 CONTROL_SUPPRESS_LOCAL_FIXUPS,
206 #ifdef WITH_CONTENT_SCAN
207 CONTROL_NO_MBOX_UNSPOOL,
211 CONTROL_NO_MULTILINE,
212 CONTROL_NO_PIPELINING,
213 CONTROL_NO_DELAY_FLUSH,
214 CONTROL_NO_CALLOUT_FLUSH
217 /* ACL control names; keep in step with the table above! This list is used for
218 turning ids into names. The actual list of recognized names is in the variable
219 control_def controls_list[] below. The fact that there are two lists is a mess
220 and should be tidied up. */
222 static uschar *controls[] = {
223 US"allow_auth_unadvertised",
224 #ifdef EXPERIMENTAL_BRIGHTMAIL
229 US"dkim_disable_verify",
231 #ifdef EXPERIMENTAL_DMARC
232 US"dmarc_disable_verify",
233 US"dmarc_enable_forensic",
237 US"caseful_local_part",
238 US"caselower_local_part",
239 US"cutthrough_delivery",
245 US"suppress_local_fixups",
246 #ifdef WITH_CONTENT_SCAN
251 US"no_multiline_responses",
257 /* Flags to indicate for which conditions/modifiers a string expansion is done
258 at the outer level. In the other cases, expansion already occurs in the
259 checking functions. */
261 static uschar cond_expand_at_top[] = {
263 TRUE, /* add_header */
264 FALSE, /* authenticated */
265 #ifdef EXPERIMENTAL_BRIGHTMAIL
266 TRUE, /* bmi_optin */
268 TRUE, /* condition */
271 #ifdef EXPERIMENTAL_DCC
274 #ifdef WITH_CONTENT_SCAN
278 #ifdef WITH_OLD_DEMIME
282 TRUE, /* dkim_signers */
283 TRUE, /* dkim_status */
285 #ifdef EXPERIMENTAL_DMARC
286 TRUE, /* dmarc_status */
290 FALSE, /* encrypted */
293 FALSE, /* local_parts */
294 TRUE, /* log_message */
295 TRUE, /* log_reject_target */
297 #ifdef WITH_CONTENT_SCAN
301 #ifdef WITH_CONTENT_SCAN
302 TRUE, /* mime_regex */
304 TRUE, /* ratelimit */
305 FALSE, /* recipients */
306 #ifdef WITH_CONTENT_SCAN
309 TRUE, /* remove_header */
310 FALSE, /* sender_domains */
313 #ifdef WITH_CONTENT_SCAN
316 #ifdef EXPERIMENTAL_SPF
318 TRUE, /* spf_guess */
324 /* Flags to identify the modifiers */
326 static uschar cond_modifiers[] = {
328 TRUE, /* add_header */
329 FALSE, /* authenticated */
330 #ifdef EXPERIMENTAL_BRIGHTMAIL
331 TRUE, /* bmi_optin */
333 FALSE, /* condition */
336 #ifdef EXPERIMENTAL_DCC
339 #ifdef WITH_CONTENT_SCAN
343 #ifdef WITH_OLD_DEMIME
347 FALSE, /* dkim_signers */
348 FALSE, /* dkim_status */
350 #ifdef EXPERIMENTAL_DMARC
351 FALSE, /* dmarc_status */
353 FALSE, /* dnslists */
355 FALSE, /* encrypted */
358 FALSE, /* local_parts */
359 TRUE, /* log_message */
360 TRUE, /* log_reject_target */
362 #ifdef WITH_CONTENT_SCAN
366 #ifdef WITH_CONTENT_SCAN
367 FALSE, /* mime_regex */
369 FALSE, /* ratelimit */
370 FALSE, /* recipients */
371 #ifdef WITH_CONTENT_SCAN
374 TRUE, /* remove_header */
375 FALSE, /* sender_domains */
378 #ifdef WITH_CONTENT_SCAN
381 #ifdef EXPERIMENTAL_SPF
383 FALSE, /* spf_guess */
389 /* Bit map vector of which conditions and modifiers are not allowed at certain
390 times. For each condition and modifier, there's a bitmap of dis-allowed times.
391 For some, it is easier to specify the negation of a small number of allowed
394 static unsigned int cond_forbids[] = {
398 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* add_header */
399 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
400 #ifdef EXPERIMENTAL_PRDR
403 (1<<ACL_WHERE_MIME)|(1<<ACL_WHERE_NOTSMTP)|
405 (1<<ACL_WHERE_NOTSMTP_START)),
407 (1<<ACL_WHERE_NOTSMTP)| /* authenticated */
408 (1<<ACL_WHERE_NOTSMTP_START)|
409 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO),
411 #ifdef EXPERIMENTAL_BRIGHTMAIL
412 (1<<ACL_WHERE_AUTH)| /* bmi_optin */
413 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
414 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_MIME)|
415 #ifdef EXPERIMENTAL_PRDR
418 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
419 (1<<ACL_WHERE_MAILAUTH)|
420 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
421 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_PREDATA)|
422 (1<<ACL_WHERE_NOTSMTP_START),
429 /* Certain types of control are always allowed, so we let it through
430 always and check in the control processing itself. */
434 #ifdef EXPERIMENTAL_DCC
436 ~((1<<ACL_WHERE_DATA)| /* dcc */
437 #ifdef EXPERIMENTAL_PRDR
439 #endif /* EXPERIMENTAL_PRDR */
440 (1<<ACL_WHERE_NOTSMTP)),
443 #ifdef WITH_CONTENT_SCAN
445 ~(1<<ACL_WHERE_MIME), /* decode */
448 (1<<ACL_WHERE_NOTQUIT), /* delay */
450 #ifdef WITH_OLD_DEMIME
452 ~((1<<ACL_WHERE_DATA)| /* demime */
453 #ifdef EXPERIMENTAL_PRDR
455 #endif /* EXPERIMENTAL_PRDR */
456 (1<<ACL_WHERE_NOTSMTP)),
461 ~(1<<ACL_WHERE_DKIM), /* dkim_signers */
464 ~(1<<ACL_WHERE_DKIM), /* dkim_status */
467 #ifdef EXPERIMENTAL_DMARC
469 ~(1<<ACL_WHERE_DATA), /* dmarc_status */
472 (1<<ACL_WHERE_NOTSMTP)| /* dnslists */
473 (1<<ACL_WHERE_NOTSMTP_START),
476 ~((1<<ACL_WHERE_RCPT) /* domains */
477 #ifdef EXPERIMENTAL_PRDR
482 (1<<ACL_WHERE_NOTSMTP)| /* encrypted */
483 (1<<ACL_WHERE_CONNECT)|
484 (1<<ACL_WHERE_NOTSMTP_START)|
489 (1<<ACL_WHERE_NOTSMTP)| /* hosts */
490 (1<<ACL_WHERE_NOTSMTP_START),
493 ~((1<<ACL_WHERE_RCPT) /* local_parts */
494 #ifdef EXPERIMENTAL_PRDR
501 0, /* log_reject_target */
505 #ifdef WITH_CONTENT_SCAN
507 ~((1<<ACL_WHERE_DATA)| /* malware */
508 #ifdef EXPERIMENTAL_PRDR
510 #endif /* EXPERIMENTAL_PRDR */
511 (1<<ACL_WHERE_NOTSMTP)),
516 #ifdef WITH_CONTENT_SCAN
518 ~(1<<ACL_WHERE_MIME), /* mime_regex */
524 ~(1<<ACL_WHERE_RCPT), /* recipients */
526 #ifdef WITH_CONTENT_SCAN
528 ~((1<<ACL_WHERE_DATA)| /* regex */
529 #ifdef EXPERIMENTAL_PRDR
531 #endif /* EXPERIMENTAL_PRDR */
532 (1<<ACL_WHERE_NOTSMTP)|
533 (1<<ACL_WHERE_MIME)),
537 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* remove_header */
538 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
539 #ifdef EXPERIMENTAL_PRDR
542 (1<<ACL_WHERE_MIME)|(1<<ACL_WHERE_NOTSMTP)|
543 (1<<ACL_WHERE_NOTSMTP_START)),
545 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* sender_domains */
547 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
548 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
549 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
551 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* senders */
553 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
554 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
555 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
559 #ifdef WITH_CONTENT_SCAN
561 ~((1<<ACL_WHERE_DATA)| /* spam */
562 #ifdef EXPERIMENTAL_PRDR
564 #endif /* EXPERIMENTAL_PRDR */
565 (1<<ACL_WHERE_NOTSMTP)),
568 #ifdef EXPERIMENTAL_SPF
569 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* spf */
571 (1<<ACL_WHERE_MAILAUTH)|
572 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
573 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY)|
574 (1<<ACL_WHERE_NOTSMTP)|
575 (1<<ACL_WHERE_NOTSMTP_START),
577 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* spf_guess */
579 (1<<ACL_WHERE_MAILAUTH)|
580 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
581 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY)|
582 (1<<ACL_WHERE_NOTSMTP)|
583 (1<<ACL_WHERE_NOTSMTP_START),
588 /* Certain types of verify are always allowed, so we let it through
589 always and check in the verify function itself */
595 /* Bit map vector of which controls are not allowed at certain times. For
596 each control, there's a bitmap of dis-allowed times. For some, it is easier to
597 specify the negation of a small number of allowed times. */
599 static unsigned int control_forbids[] = {
601 ~((1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)), /* allow_auth_unadvertised */
603 #ifdef EXPERIMENTAL_BRIGHTMAIL
610 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* dkim_disable_verify */
611 #ifdef EXPERIMENTAL_PRDR
613 #endif /* EXPERIMENTAL_PRDR */
614 (1<<ACL_WHERE_NOTSMTP_START),
617 #ifdef EXPERIMENTAL_DMARC
618 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* dmarc_disable_verify */
619 (1<<ACL_WHERE_NOTSMTP_START),
620 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* dmarc_enable_forensic */
621 (1<<ACL_WHERE_NOTSMTP_START),
624 (1<<ACL_WHERE_NOTSMTP)|
625 (1<<ACL_WHERE_NOTSMTP_START)|
626 (1<<ACL_WHERE_NOTQUIT), /* dscp */
631 ~(1<<ACL_WHERE_RCPT), /* caseful_local_part */
634 ~(1<<ACL_WHERE_RCPT), /* caselower_local_part */
637 0, /* cutthrough_delivery */
639 (1<<ACL_WHERE_NOTSMTP)| /* enforce_sync */
640 (1<<ACL_WHERE_NOTSMTP_START),
642 (1<<ACL_WHERE_NOTSMTP)| /* no_enforce_sync */
643 (1<<ACL_WHERE_NOTSMTP_START),
646 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* freeze */
647 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
648 // (1<<ACL_WHERE_PRDR)| /* Not allow one user to freeze for all */
649 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)),
652 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* queue_only */
653 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
654 // (1<<ACL_WHERE_PRDR)| /* Not allow one user to freeze for all */
655 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)),
658 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* submission */
659 (1<<ACL_WHERE_PREDATA)),
662 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* suppress_local_fixups */
663 (1<<ACL_WHERE_PREDATA)|
664 (1<<ACL_WHERE_NOTSMTP_START)),
666 #ifdef WITH_CONTENT_SCAN
668 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* no_mbox_unspool */
669 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
670 // (1<<ACL_WHERE_PRDR)| /* Not allow one user to freeze for all */
671 (1<<ACL_WHERE_MIME)),
675 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakedefer */
676 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
677 #ifdef EXPERIMENTAL_PRDR
679 #endif /* EXPERIMENTAL_PRDR */
680 (1<<ACL_WHERE_MIME)),
683 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakereject */
684 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
685 #ifdef EXPERIMENTAL_PRDR
687 #endif /* EXPERIMENTAL_PRDR */
688 (1<<ACL_WHERE_MIME)),
690 (1<<ACL_WHERE_NOTSMTP)| /* no_multiline */
691 (1<<ACL_WHERE_NOTSMTP_START),
693 (1<<ACL_WHERE_NOTSMTP)| /* no_pipelining */
694 (1<<ACL_WHERE_NOTSMTP_START),
696 (1<<ACL_WHERE_NOTSMTP)| /* no_delay_flush */
697 (1<<ACL_WHERE_NOTSMTP_START),
699 (1<<ACL_WHERE_NOTSMTP)| /* no_callout_flush */
700 (1<<ACL_WHERE_NOTSMTP_START)
703 /* Structure listing various control arguments, with their characteristics. */
705 typedef struct control_def {
707 int value; /* CONTROL_xxx value */
708 BOOL has_option; /* Has /option(s) following */
711 static control_def controls_list[] = {
712 { US"allow_auth_unadvertised", CONTROL_AUTH_UNADVERTISED, FALSE },
713 #ifdef EXPERIMENTAL_BRIGHTMAIL
714 { US"bmi_run", CONTROL_BMI_RUN, FALSE },
716 { US"debug", CONTROL_DEBUG, TRUE },
718 { US"dkim_disable_verify", CONTROL_DKIM_VERIFY, FALSE },
720 #ifdef EXPERIMENTAL_DMARC
721 { US"dmarc_disable_verify", CONTROL_DMARC_VERIFY, FALSE },
722 { US"dmarc_enable_forensic", CONTROL_DMARC_FORENSIC, FALSE },
724 { US"dscp", CONTROL_DSCP, TRUE },
725 { US"caseful_local_part", CONTROL_CASEFUL_LOCAL_PART, FALSE },
726 { US"caselower_local_part", CONTROL_CASELOWER_LOCAL_PART, FALSE },
727 { US"enforce_sync", CONTROL_ENFORCE_SYNC, FALSE },
728 { US"freeze", CONTROL_FREEZE, TRUE },
729 { US"no_callout_flush", CONTROL_NO_CALLOUT_FLUSH, FALSE },
730 { US"no_delay_flush", CONTROL_NO_DELAY_FLUSH, FALSE },
731 { US"no_enforce_sync", CONTROL_NO_ENFORCE_SYNC, FALSE },
732 { US"no_multiline_responses", CONTROL_NO_MULTILINE, FALSE },
733 { US"no_pipelining", CONTROL_NO_PIPELINING, FALSE },
734 { US"queue_only", CONTROL_QUEUE_ONLY, FALSE },
735 #ifdef WITH_CONTENT_SCAN
736 { US"no_mbox_unspool", CONTROL_NO_MBOX_UNSPOOL, FALSE },
738 { US"fakedefer", CONTROL_FAKEDEFER, TRUE },
739 { US"fakereject", CONTROL_FAKEREJECT, TRUE },
740 { US"submission", CONTROL_SUBMISSION, TRUE },
741 { US"suppress_local_fixups", CONTROL_SUPPRESS_LOCAL_FIXUPS, FALSE },
742 { US"cutthrough_delivery", CONTROL_CUTTHROUGH_DELIVERY, FALSE }
745 /* Support data structures for Client SMTP Authorization. acl_verify_csa()
746 caches its result in a tree to avoid repeated DNS queries. The result is an
747 integer code which is used as an index into the following tables of
748 explanatory strings and verification return codes. */
750 static tree_node *csa_cache = NULL;
752 enum { CSA_UNKNOWN, CSA_OK, CSA_DEFER_SRV, CSA_DEFER_ADDR,
753 CSA_FAIL_EXPLICIT, CSA_FAIL_DOMAIN, CSA_FAIL_NOADDR, CSA_FAIL_MISMATCH };
755 /* The acl_verify_csa() return code is translated into an acl_verify() return
756 code using the following table. It is OK unless the client is definitely not
757 authorized. This is because CSA is supposed to be optional for sending sites,
758 so recipients should not be too strict about checking it - especially because
759 DNS problems are quite likely to occur. It's possible to use $csa_status in
760 further ACL conditions to distinguish ok, unknown, and defer if required, but
761 the aim is to make the usual configuration simple. */
763 static int csa_return_code[] = {
765 FAIL, FAIL, FAIL, FAIL
768 static uschar *csa_status_string[] = {
769 US"unknown", US"ok", US"defer", US"defer",
770 US"fail", US"fail", US"fail", US"fail"
773 static uschar *csa_reason_string[] = {
776 US"deferred (SRV lookup failed)",
777 US"deferred (target address lookup failed)",
778 US"failed (explicit authorization required)",
779 US"failed (host name not authorized)",
780 US"failed (no authorized addresses)",
781 US"failed (client address mismatch)"
784 /* Options for the ratelimit condition. Note that there are two variants of
785 the per_rcpt option, depending on the ACL that is used to measure the rate.
786 However any ACL must be able to look up per_rcpt rates in /noupdate mode,
787 so the two variants must have the same internal representation as well as
788 the same configuration string. */
791 RATE_PER_WHAT, RATE_PER_CLASH, RATE_PER_ADDR, RATE_PER_BYTE, RATE_PER_CMD,
792 RATE_PER_CONN, RATE_PER_MAIL, RATE_PER_RCPT, RATE_PER_ALLRCPTS
795 #define RATE_SET(var,new) \
796 (((var) == RATE_PER_WHAT) ? ((var) = RATE_##new) : ((var) = RATE_PER_CLASH))
798 static uschar *ratelimit_option_string[] = {
799 US"?", US"!", US"per_addr", US"per_byte", US"per_cmd",
800 US"per_conn", US"per_mail", US"per_rcpt", US"per_rcpt"
803 /* Enable recursion between acl_check_internal() and acl_check_condition() */
805 static int acl_check_wargs(int, address_item *, uschar *, int, uschar **,
809 /*************************************************
810 * Pick out name from list *
811 *************************************************/
813 /* Use a binary chop method
820 Returns: offset in list, or -1 if not found
824 acl_checkname(uschar *name, uschar **list, int end)
830 int mid = (start + end)/2;
831 int c = Ustrcmp(name, list[mid]);
832 if (c == 0) return mid;
833 if (c < 0) end = mid; else start = mid + 1;
840 /*************************************************
841 * Read and parse one ACL *
842 *************************************************/
844 /* This function is called both from readconf in order to parse the ACLs in the
845 configuration file, and also when an ACL is encountered dynamically (e.g. as
846 the result of an expansion). It is given a function to call in order to
847 retrieve the lines of the ACL. This function handles skipping comments and
848 blank lines (where relevant).
851 func function to get next line of ACL
852 error where to put an error message
854 Returns: pointer to ACL, or NULL
855 NULL can be legal (empty ACL); in this case error will be NULL
859 acl_read(uschar *(*func)(void), uschar **error)
861 acl_block *yield = NULL;
862 acl_block **lastp = &yield;
863 acl_block *this = NULL;
864 acl_condition_block *cond;
865 acl_condition_block **condp = NULL;
870 while ((s = (*func)()) != NULL)
873 BOOL negated = FALSE;
874 uschar *saveline = s;
877 /* Conditions (but not verbs) are allowed to be negated by an initial
880 while (isspace(*s)) s++;
887 /* Read the name of a verb or a condition, or the start of a new ACL, which
888 can be started by a name, or by a macro definition. */
890 s = readconf_readname(name, sizeof(name), s);
891 if (*s == ':' || (isupper(name[0]) && *s == '=')) return yield;
893 /* If a verb is unrecognized, it may be another condition or modifier that
894 continues the previous verb. */
896 v = acl_checkname(name, verbs, sizeof(verbs)/sizeof(char *));
901 *error = string_sprintf("unknown ACL verb \"%s\" in \"%s\"", name,
913 *error = string_sprintf("malformed ACL line \"%s\"", saveline);
916 this = store_get(sizeof(acl_block));
918 lastp = &(this->next);
921 this->condition = NULL;
922 condp = &(this->condition);
923 if (*s == 0) continue; /* No condition on this line */
929 s = readconf_readname(name, sizeof(name), s); /* Condition name */
932 /* Handle a condition or modifier. */
934 c = acl_checkname(name, conditions, sizeof(conditions)/sizeof(char *));
937 *error = string_sprintf("unknown ACL condition/modifier in \"%s\"",
942 /* The modifiers may not be negated */
944 if (negated && cond_modifiers[c])
946 *error = string_sprintf("ACL error: negation is not allowed with "
947 "\"%s\"", conditions[c]);
951 /* ENDPASS may occur only with ACCEPT or DISCARD. */
953 if (c == ACLC_ENDPASS &&
954 this->verb != ACL_ACCEPT &&
955 this->verb != ACL_DISCARD)
957 *error = string_sprintf("ACL error: \"%s\" is not allowed with \"%s\"",
958 conditions[c], verbs[this->verb]);
962 cond = store_get(sizeof(acl_condition_block));
965 cond->u.negated = negated;
968 condp = &(cond->next);
970 /* The "set" modifier is different in that its argument is "name=value"
971 rather than just a value, and we can check the validity of the name, which
972 gives us a variable name to insert into the data block. The original ACL
973 variable names were acl_c0 ... acl_c9 and acl_m0 ... acl_m9. This was
974 extended to 20 of each type, but after that people successfully argued for
975 arbitrary names. In the new scheme, the names must start with acl_c or acl_m.
976 After that, we allow alphanumerics and underscores, but the first character
977 after c or m must be a digit or an underscore. This retains backwards
984 if (Ustrncmp(s, "acl_c", 5) != 0 &&
985 Ustrncmp(s, "acl_m", 5) != 0)
987 *error = string_sprintf("invalid variable name after \"set\" in ACL "
988 "modifier \"set %s\" (must start \"acl_c\" or \"acl_m\")", s);
993 if (!isdigit(*endptr) && *endptr != '_')
995 *error = string_sprintf("invalid variable name after \"set\" in ACL "
996 "modifier \"set %s\" (digit or underscore must follow acl_c or acl_m)",
1001 while (*endptr != 0 && *endptr != '=' && !isspace(*endptr))
1003 if (!isalnum(*endptr) && *endptr != '_')
1005 *error = string_sprintf("invalid character \"%c\" in variable name "
1006 "in ACL modifier \"set %s\"", *endptr, s);
1012 cond->u.varname = string_copyn(s + 4, endptr - s - 4);
1014 while (isspace(*s)) s++;
1017 /* For "set", we are now positioned for the data. For the others, only
1018 "endpass" has no data */
1020 if (c != ACLC_ENDPASS)
1024 *error = string_sprintf("\"=\" missing after ACL \"%s\" %s", name,
1025 cond_modifiers[c]? US"modifier" : US"condition");
1028 while (isspace(*s)) s++;
1029 cond->arg = string_copy(s);
1038 /*************************************************
1039 * Set up added header line(s) *
1040 *************************************************/
1042 /* This function is called by the add_header modifier, and also from acl_warn()
1043 to implement the now-deprecated way of adding header lines using "message" on a
1044 "warn" verb. The argument is treated as a sequence of header lines which are
1045 added to a chain, provided there isn't an identical one already there.
1047 Argument: string of header lines
1052 setup_header(uschar *hstring)
1055 int hlen = Ustrlen(hstring);
1057 /* Ignore any leading newlines */
1058 while (*hstring == '\n') hstring++, hlen--;
1060 /* An empty string does nothing; ensure exactly one final newline. */
1061 if (hlen <= 0) return;
1062 if (hstring[--hlen] != '\n') hstring = string_sprintf("%s\n", hstring);
1063 else while(hstring[--hlen] == '\n') hstring[hlen+1] = '\0';
1065 /* Loop for multiple header lines, taking care about continuations */
1067 for (p = q = hstring; *p != 0; )
1070 int newtype = htype_add_bot;
1071 header_line **hptr = &acl_added_headers;
1073 /* Find next header line within the string */
1077 q = Ustrchr(q, '\n');
1078 if (*(++q) != ' ' && *q != '\t') break;
1081 /* If the line starts with a colon, interpret the instruction for where to
1082 add it. This temporarily sets up a new type. */
1086 if (strncmpic(p, US":after_received:", 16) == 0)
1088 newtype = htype_add_rec;
1091 else if (strncmpic(p, US":at_start_rfc:", 14) == 0)
1093 newtype = htype_add_rfc;
1096 else if (strncmpic(p, US":at_start:", 10) == 0)
1098 newtype = htype_add_top;
1101 else if (strncmpic(p, US":at_end:", 8) == 0)
1103 newtype = htype_add_bot;
1106 while (*p == ' ' || *p == '\t') p++;
1109 /* See if this line starts with a header name, and if not, add X-ACL-Warn:
1110 to the front of it. */
1112 for (s = p; s < q - 1; s++)
1114 if (*s == ':' || !isgraph(*s)) break;
1117 s = string_sprintf("%s%.*s", (*s == ':')? "" : "X-ACL-Warn: ", (int) (q - p), p);
1120 /* See if this line has already been added */
1122 while (*hptr != NULL)
1124 if (Ustrncmp((*hptr)->text, s, hlen) == 0) break;
1125 hptr = &((*hptr)->next);
1128 /* Add if not previously present */
1132 header_line *h = store_get(sizeof(header_line));
1141 /* Advance for next header line within the string */
1149 /*************************************************
1150 * List the added header lines *
1151 *************************************************/
1155 uschar * ret = NULL;
1156 header_line * h = acl_added_headers;
1162 if (!h) return NULL;
1167 while ((cp = Ustrchr(s, '\n')) != NULL)
1169 if (cp[1] == '\0') break;
1171 /* contains embedded newline; needs doubling */
1172 ret = string_cat(ret, &size, &ptr, s, cp-s+1);
1173 ret = string_cat(ret, &size, &ptr, US"\n", 1);
1176 /* last bit of header */
1178 ret = string_cat(ret, &size, &ptr, s, cp-s+1); /* newline-sep list */
1180 while((h = h->next));
1182 ret[ptr-1] = '\0'; /* overwrite last newline */
1187 /*************************************************
1188 * Set up removed header line(s) *
1189 *************************************************/
1191 /* This function is called by the remove_header modifier. The argument is
1192 treated as a sequence of header names which are added to a colon separated
1193 list, provided there isn't an identical one already there.
1195 Argument: string of header names
1200 setup_remove_header(uschar *hnames)
1204 if (acl_removed_headers == NULL)
1205 acl_removed_headers = hnames;
1207 acl_removed_headers = string_sprintf("%s : %s", acl_removed_headers, hnames);
1213 /*************************************************
1215 *************************************************/
1217 /* This function is called when a WARN verb's conditions are true. It adds to
1218 the message's headers, and/or writes information to the log. In each case, this
1219 only happens once (per message for headers, per connection for log).
1221 ** NOTE: The header adding action using the "message" setting is historic, and
1222 its use is now deprecated. The new add_header modifier should be used instead.
1225 where ACL_WHERE_xxxx indicating which ACL this is
1226 user_message message for adding to headers
1227 log_message message for logging, if different
1233 acl_warn(int where, uschar *user_message, uschar *log_message)
1235 if (log_message != NULL && log_message != user_message)
1238 string_item *logged;
1240 text = string_sprintf("%s Warning: %s", host_and_ident(TRUE),
1241 string_printing(log_message));
1243 /* If a sender verification has failed, and the log message is "sender verify
1244 failed", add the failure message. */
1246 if (sender_verified_failed != NULL &&
1247 sender_verified_failed->message != NULL &&
1248 strcmpic(log_message, US"sender verify failed") == 0)
1249 text = string_sprintf("%s: %s", text, sender_verified_failed->message);
1251 /* Search previously logged warnings. They are kept in malloc
1252 store so they can be freed at the start of a new message. */
1254 for (logged = acl_warn_logged; logged != NULL; logged = logged->next)
1255 if (Ustrcmp(logged->text, text) == 0) break;
1259 int length = Ustrlen(text) + 1;
1260 log_write(0, LOG_MAIN, "%s", text);
1261 logged = store_malloc(sizeof(string_item) + length);
1262 logged->text = (uschar *)logged + sizeof(string_item);
1263 memcpy(logged->text, text, length);
1264 logged->next = acl_warn_logged;
1265 acl_warn_logged = logged;
1269 /* If there's no user message, we are done. */
1271 if (user_message == NULL) return;
1273 /* If this isn't a message ACL, we can't do anything with a user message.
1276 if (where > ACL_WHERE_NOTSMTP)
1278 log_write(0, LOG_MAIN|LOG_PANIC, "ACL \"warn\" with \"message\" setting "
1279 "found in a non-message (%s) ACL: cannot specify header lines here: "
1280 "message ignored", acl_wherenames[where]);
1284 /* The code for setting up header lines is now abstracted into a separate
1285 function so that it can be used for the add_header modifier as well. */
1287 setup_header(user_message);
1292 /*************************************************
1293 * Verify and check reverse DNS *
1294 *************************************************/
1296 /* Called from acl_verify() below. We look up the host name(s) of the client IP
1297 address if this has not yet been done. The host_name_lookup() function checks
1298 that one of these names resolves to an address list that contains the client IP
1299 address, so we don't actually have to do the check here.
1302 user_msgptr pointer for user message
1303 log_msgptr pointer for log message
1305 Returns: OK verification condition succeeded
1306 FAIL verification failed
1307 DEFER there was a problem verifying
1311 acl_verify_reverse(uschar **user_msgptr, uschar **log_msgptr)
1315 user_msgptr = user_msgptr; /* stop compiler warning */
1317 /* Previous success */
1319 if (sender_host_name != NULL) return OK;
1321 /* Previous failure */
1323 if (host_lookup_failed)
1325 *log_msgptr = string_sprintf("host lookup failed%s", host_lookup_msg);
1329 /* Need to do a lookup */
1332 debug_printf("looking up host name to force name/address consistency check\n");
1334 if ((rc = host_name_lookup()) != OK)
1336 *log_msgptr = (rc == DEFER)?
1337 US"host lookup deferred for reverse lookup check"
1339 string_sprintf("host lookup failed for reverse lookup check%s",
1341 return rc; /* DEFER or FAIL */
1344 host_build_sender_fullhost();
1350 /*************************************************
1351 * Check client IP address matches CSA target *
1352 *************************************************/
1354 /* Called from acl_verify_csa() below. This routine scans a section of a DNS
1355 response for address records belonging to the CSA target hostname. The section
1356 is specified by the reset argument, either RESET_ADDITIONAL or RESET_ANSWERS.
1357 If one of the addresses matches the client's IP address, then the client is
1358 authorized by CSA. If there are target IP addresses but none of them match
1359 then the client is using an unauthorized IP address. If there are no target IP
1360 addresses then the client cannot be using an authorized IP address. (This is
1361 an odd configuration - why didn't the SRV record have a weight of 1 instead?)
1364 dnsa the DNS answer block
1365 dnss a DNS scan block for us to use
1366 reset option specifing what portion to scan, as described above
1367 target the target hostname to use for matching RR names
1369 Returns: CSA_OK successfully authorized
1370 CSA_FAIL_MISMATCH addresses found but none matched
1371 CSA_FAIL_NOADDR no target addresses found
1375 acl_verify_csa_address(dns_answer *dnsa, dns_scan *dnss, int reset,
1381 BOOL target_found = FALSE;
1383 for (rr = dns_next_rr(dnsa, dnss, reset);
1385 rr = dns_next_rr(dnsa, dnss, RESET_NEXT))
1387 /* Check this is an address RR for the target hostname. */
1391 && rr->type != T_AAAA
1398 if (strcmpic(target, rr->name) != 0) continue;
1400 target_found = TRUE;
1402 /* Turn the target address RR into a list of textual IP addresses and scan
1403 the list. There may be more than one if it is an A6 RR. */
1405 for (da = dns_address_from_rr(dnsa, rr); da != NULL; da = da->next)
1407 /* If the client IP address matches the target IP address, it's good! */
1409 DEBUG(D_acl) debug_printf("CSA target address is %s\n", da->address);
1411 if (strcmpic(sender_host_address, da->address) == 0) return CSA_OK;
1415 /* If we found some target addresses but none of them matched, the client is
1416 using an unauthorized IP address, otherwise the target has no authorized IP
1419 if (target_found) return CSA_FAIL_MISMATCH;
1420 else return CSA_FAIL_NOADDR;
1425 /*************************************************
1426 * Verify Client SMTP Authorization *
1427 *************************************************/
1429 /* Called from acl_verify() below. This routine calls dns_lookup_special()
1430 to find the CSA SRV record corresponding to the domain argument, or
1431 $sender_helo_name if no argument is provided. It then checks that the
1432 client is authorized, and that its IP address corresponds to the SRV
1433 target's address by calling acl_verify_csa_address() above. The address
1434 should have been returned in the DNS response's ADDITIONAL section, but if
1435 not we perform another DNS lookup to get it.
1438 domain pointer to optional parameter following verify = csa
1440 Returns: CSA_UNKNOWN no valid CSA record found
1441 CSA_OK successfully authorized
1442 CSA_FAIL_* client is definitely not authorized
1443 CSA_DEFER_* there was a DNS problem
1447 acl_verify_csa(uschar *domain)
1451 int priority, weight, port;
1458 /* Work out the domain we are using for the CSA lookup. The default is the
1459 client's HELO domain. If the client has not said HELO, use its IP address
1460 instead. If it's a local client (exim -bs), CSA isn't applicable. */
1462 while (isspace(*domain) && *domain != '\0') ++domain;
1463 if (*domain == '\0') domain = sender_helo_name;
1464 if (domain == NULL) domain = sender_host_address;
1465 if (sender_host_address == NULL) return CSA_UNKNOWN;
1467 /* If we have an address literal, strip off the framing ready for turning it
1468 into a domain. The framing consists of matched square brackets possibly
1469 containing a keyword and a colon before the actual IP address. */
1471 if (domain[0] == '[')
1473 uschar *start = Ustrchr(domain, ':');
1474 if (start == NULL) start = domain;
1475 domain = string_copyn(start + 1, Ustrlen(start) - 2);
1478 /* Turn domains that look like bare IP addresses into domains in the reverse
1479 DNS. This code also deals with address literals and $sender_host_address. It's
1480 not quite kosher to treat bare domains such as EHLO 192.0.2.57 the same as
1481 address literals, but it's probably the most friendly thing to do. This is an
1482 extension to CSA, so we allow it to be turned off for proper conformance. */
1484 if (string_is_ip_address(domain, NULL) != 0)
1486 if (!dns_csa_use_reverse) return CSA_UNKNOWN;
1487 dns_build_reverse(domain, target);
1491 /* Find out if we've already done the CSA check for this domain. If we have,
1492 return the same result again. Otherwise build a new cached result structure
1493 for this domain. The name is filled in now, and the value is filled in when
1494 we return from this function. */
1496 t = tree_search(csa_cache, domain);
1497 if (t != NULL) return t->data.val;
1499 t = store_get_perm(sizeof(tree_node) + Ustrlen(domain));
1500 Ustrcpy(t->name, domain);
1501 (void)tree_insertnode(&csa_cache, t);
1503 /* Now we are ready to do the actual DNS lookup(s). */
1506 switch (dns_special_lookup(&dnsa, domain, T_CSA, &found))
1508 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1511 return t->data.val = CSA_DEFER_SRV;
1513 /* If we found nothing, the client's authorization is unknown. */
1517 return t->data.val = CSA_UNKNOWN;
1519 /* We got something! Go on to look at the reply in more detail. */
1525 /* Scan the reply for well-formed CSA SRV records. */
1527 for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS);
1529 rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT))
1531 if (rr->type != T_SRV) continue;
1533 /* Extract the numerical SRV fields (p is incremented) */
1536 GETSHORT(priority, p);
1537 GETSHORT(weight, p);
1541 debug_printf("CSA priority=%d weight=%d port=%d\n", priority, weight, port);
1543 /* Check the CSA version number */
1545 if (priority != 1) continue;
1547 /* If the domain does not have a CSA SRV record of its own (i.e. the domain
1548 found by dns_special_lookup() is a parent of the one we asked for), we check
1549 the subdomain assertions in the port field. At the moment there's only one
1550 assertion: legitimate SMTP clients are all explicitly authorized with CSA
1551 SRV records of their own. */
1553 if (found != domain)
1556 return t->data.val = CSA_FAIL_EXPLICIT;
1558 return t->data.val = CSA_UNKNOWN;
1561 /* This CSA SRV record refers directly to our domain, so we check the value
1562 in the weight field to work out the domain's authorization. 0 and 1 are
1563 unauthorized; 3 means the client is authorized but we can't check the IP
1564 address in order to authenticate it, so we treat it as unknown; values
1565 greater than 3 are undefined. */
1567 if (weight < 2) return t->data.val = CSA_FAIL_DOMAIN;
1569 if (weight > 2) continue;
1571 /* Weight == 2, which means the domain is authorized. We must check that the
1572 client's IP address is listed as one of the SRV target addresses. Save the
1573 target hostname then break to scan the additional data for its addresses. */
1575 (void)dn_expand(dnsa.answer, dnsa.answer + dnsa.answerlen, p,
1576 (DN_EXPAND_ARG4_TYPE)target, sizeof(target));
1578 DEBUG(D_acl) debug_printf("CSA target is %s\n", target);
1583 /* If we didn't break the loop then no appropriate records were found. */
1585 if (rr == NULL) return t->data.val = CSA_UNKNOWN;
1587 /* Do not check addresses if the target is ".", in accordance with RFC 2782.
1588 A target of "." indicates there are no valid addresses, so the client cannot
1589 be authorized. (This is an odd configuration because weight=2 target=. is
1590 equivalent to weight=1, but we check for it in order to keep load off the
1591 root name servers.) Note that dn_expand() turns "." into "". */
1593 if (Ustrcmp(target, "") == 0) return t->data.val = CSA_FAIL_NOADDR;
1595 /* Scan the additional section of the CSA SRV reply for addresses belonging
1596 to the target. If the name server didn't return any additional data (e.g.
1597 because it does not fully support SRV records), we need to do another lookup
1598 to obtain the target addresses; otherwise we have a definitive result. */
1600 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ADDITIONAL, target);
1601 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1603 /* The DNS lookup type corresponds to the IP version used by the client. */
1606 if (Ustrchr(sender_host_address, ':') != NULL)
1609 #endif /* HAVE_IPV6 */
1613 #if HAVE_IPV6 && defined(SUPPORT_A6)
1617 switch (dns_lookup(&dnsa, target, type, NULL))
1619 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1622 return t->data.val = CSA_DEFER_ADDR;
1624 /* If the query succeeded, scan the addresses and return the result. */
1627 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ANSWERS, target);
1628 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1629 /* else fall through */
1631 /* If the target has no IP addresses, the client cannot have an authorized
1632 IP address. However, if the target site uses A6 records (not AAAA records)
1633 we have to do yet another lookup in order to check them. */
1638 #if HAVE_IPV6 && defined(SUPPORT_A6)
1639 if (type == T_AAAA) { type = T_A6; goto DNS_LOOKUP_AGAIN; }
1642 return t->data.val = CSA_FAIL_NOADDR;
1648 /*************************************************
1649 * Handle verification (address & other) *
1650 *************************************************/
1652 enum { VERIFY_REV_HOST_LKUP, VERIFY_CERT, VERIFY_HELO, VERIFY_CSA, VERIFY_HDR_SYNTAX,
1653 VERIFY_NOT_BLIND, VERIFY_HDR_SNDR, VERIFY_SNDR, VERIFY_RCPT
1658 unsigned where_allowed; /* bitmap */
1659 BOOL no_options; /* Never has /option(s) following */
1660 unsigned alt_opt_sep; /* >0 Non-/ option separator (custom parser) */
1662 static verify_type_t verify_type_list[] = {
1663 { US"reverse_host_lookup", VERIFY_REV_HOST_LKUP, ~0, TRUE, 0 },
1664 { US"certificate", VERIFY_CERT, ~0, TRUE, 0 },
1665 { US"helo", VERIFY_HELO, ~0, TRUE, 0 },
1666 { US"csa", VERIFY_CSA, ~0, FALSE, 0 },
1667 { US"header_syntax", VERIFY_HDR_SYNTAX, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), TRUE, 0 },
1668 { US"not_blind", VERIFY_NOT_BLIND, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), TRUE, 0 },
1669 { US"header_sender", VERIFY_HDR_SNDR, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), FALSE, 0 },
1670 { US"sender", VERIFY_SNDR, (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)
1671 |(1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP),
1673 { US"recipient", VERIFY_RCPT, (1<<ACL_WHERE_RCPT), FALSE, 0 }
1677 enum { CALLOUT_DEFER_OK, CALLOUT_NOCACHE, CALLOUT_RANDOM, CALLOUT_USE_SENDER,
1678 CALLOUT_USE_POSTMASTER, CALLOUT_POSTMASTER, CALLOUT_FULLPOSTMASTER,
1679 CALLOUT_MAILFROM, CALLOUT_POSTMASTER_MAILFROM, CALLOUT_MAXWAIT, CALLOUT_CONNECT,
1686 BOOL has_option; /* Has =option(s) following */
1687 BOOL timeval; /* Has a time value */
1689 static callout_opt_t callout_opt_list[] = {
1690 { US"defer_ok", CALLOUT_DEFER_OK, 0, FALSE, FALSE },
1691 { US"no_cache", CALLOUT_NOCACHE, vopt_callout_no_cache, FALSE, FALSE },
1692 { US"random", CALLOUT_RANDOM, vopt_callout_random, FALSE, FALSE },
1693 { US"use_sender", CALLOUT_USE_SENDER, vopt_callout_recipsender, FALSE, FALSE },
1694 { US"use_postmaster", CALLOUT_USE_POSTMASTER,vopt_callout_recippmaster, FALSE, FALSE },
1695 { US"postmaster_mailfrom",CALLOUT_POSTMASTER_MAILFROM,0, TRUE, FALSE },
1696 { US"postmaster", CALLOUT_POSTMASTER, 0, FALSE, FALSE },
1697 { US"fullpostmaster", CALLOUT_FULLPOSTMASTER,vopt_callout_fullpm, FALSE, FALSE },
1698 { US"mailfrom", CALLOUT_MAILFROM, 0, TRUE, FALSE },
1699 { US"maxwait", CALLOUT_MAXWAIT, 0, TRUE, TRUE },
1700 { US"connect", CALLOUT_CONNECT, 0, TRUE, TRUE },
1701 { NULL, CALLOUT_TIME, 0, FALSE, TRUE }
1706 /* This function implements the "verify" condition. It is called when
1707 encountered in any ACL, because some tests are almost always permitted. Some
1708 just don't make sense, and always fail (for example, an attempt to test a host
1709 lookup for a non-TCP/IP message). Others are restricted to certain ACLs.
1712 where where called from
1713 addr the recipient address that the ACL is handling, or NULL
1714 arg the argument of "verify"
1715 user_msgptr pointer for user message
1716 log_msgptr pointer for log message
1717 basic_errno where to put verify errno
1719 Returns: OK verification condition succeeded
1720 FAIL verification failed
1721 DEFER there was a problem verifying
1726 acl_verify(int where, address_item *addr, uschar *arg,
1727 uschar **user_msgptr, uschar **log_msgptr, int *basic_errno)
1731 int callout_overall = -1;
1732 int callout_connect = -1;
1733 int verify_options = 0;
1735 BOOL verify_header_sender = FALSE;
1736 BOOL defer_ok = FALSE;
1737 BOOL callout_defer_ok = FALSE;
1738 BOOL no_details = FALSE;
1739 BOOL success_on_redirect = FALSE;
1740 address_item *sender_vaddr = NULL;
1741 uschar *verify_sender_address = NULL;
1742 uschar *pm_mailfrom = NULL;
1743 uschar *se_mailfrom = NULL;
1745 /* Some of the verify items have slash-separated options; some do not. Diagnose
1746 an error if options are given for items that don't expect them.
1749 uschar *slash = Ustrchr(arg, '/');
1751 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
1754 if (ss == NULL) goto BAD_VERIFY;
1756 /* Handle name/address consistency verification in a separate function. */
1758 for (vp= verify_type_list;
1759 (char *)vp < (char *)verify_type_list + sizeof(verify_type_list);
1762 if (vp->alt_opt_sep ? strncmpic(ss, vp->name, vp->alt_opt_sep) == 0
1763 : strcmpic (ss, vp->name) == 0)
1765 if ((char *)vp >= (char *)verify_type_list + sizeof(verify_type_list))
1768 if (vp->no_options && slash != NULL)
1770 *log_msgptr = string_sprintf("unexpected '/' found in \"%s\" "
1771 "(this verify item has no options)", arg);
1774 if (!(vp->where_allowed & (1<<where)))
1776 *log_msgptr = string_sprintf("cannot verify %s in ACL for %s", vp->name, acl_wherenames[where]);
1781 case VERIFY_REV_HOST_LKUP:
1782 if (sender_host_address == NULL) return OK;
1783 return acl_verify_reverse(user_msgptr, log_msgptr);
1786 /* TLS certificate verification is done at STARTTLS time; here we just
1787 test whether it was successful or not. (This is for optional verification; for
1788 mandatory verification, the connection doesn't last this long.) */
1790 if (tls_in.certificate_verified) return OK;
1791 *user_msgptr = US"no verified certificate";
1795 /* We can test the result of optional HELO verification that might have
1796 occurred earlier. If not, we can attempt the verification now. */
1798 if (!helo_verified && !helo_verify_failed) smtp_verify_helo();
1799 return helo_verified? OK : FAIL;
1802 /* Do Client SMTP Authorization checks in a separate function, and turn the
1803 result code into user-friendly strings. */
1805 rc = acl_verify_csa(list);
1806 *log_msgptr = *user_msgptr = string_sprintf("client SMTP authorization %s",
1807 csa_reason_string[rc]);
1808 csa_status = csa_status_string[rc];
1809 DEBUG(D_acl) debug_printf("CSA result %s\n", csa_status);
1810 return csa_return_code[rc];
1812 case VERIFY_HDR_SYNTAX:
1813 /* Check that all relevant header lines have the correct syntax. If there is
1814 a syntax error, we return details of the error to the sender if configured to
1815 send out full details. (But a "message" setting on the ACL can override, as
1818 rc = verify_check_headers(log_msgptr);
1819 if (rc != OK && smtp_return_error_details && *log_msgptr != NULL)
1820 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1823 case VERIFY_NOT_BLIND:
1824 /* Check that no recipient of this message is "blind", that is, every envelope
1825 recipient must be mentioned in either To: or Cc:. */
1827 rc = verify_check_notblind();
1830 *log_msgptr = string_sprintf("bcc recipient detected");
1831 if (smtp_return_error_details)
1832 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1836 /* The remaining verification tests check recipient and sender addresses,
1837 either from the envelope or from the header. There are a number of
1838 slash-separated options that are common to all of them. */
1840 case VERIFY_HDR_SNDR:
1841 verify_header_sender = TRUE;
1845 /* In the case of a sender, this can optionally be followed by an address to use
1846 in place of the actual sender (rare special-case requirement). */
1850 verify_sender_address = sender_address;
1853 while (isspace(*s)) s++;
1854 if (*s++ != '=') goto BAD_VERIFY;
1855 while (isspace(*s)) s++;
1856 verify_sender_address = string_copy(s);
1867 /* Remaining items are optional; they apply to sender and recipient
1868 verification, including "header sender" verification. */
1870 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size))
1873 if (strcmpic(ss, US"defer_ok") == 0) defer_ok = TRUE;
1874 else if (strcmpic(ss, US"no_details") == 0) no_details = TRUE;
1875 else if (strcmpic(ss, US"success_on_redirect") == 0) success_on_redirect = TRUE;
1877 /* These two old options are left for backwards compatibility */
1879 else if (strcmpic(ss, US"callout_defer_ok") == 0)
1881 callout_defer_ok = TRUE;
1882 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1885 else if (strcmpic(ss, US"check_postmaster") == 0)
1888 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1891 /* The callout option has a number of sub-options, comma separated */
1893 else if (strncmpic(ss, US"callout", 7) == 0)
1895 callout = CALLOUT_TIMEOUT_DEFAULT;
1899 while (isspace(*ss)) ss++;
1905 while (isspace(*ss)) ss++;
1907 while ((opt = string_nextinlist(&ss, &optsep, buffer, sizeof(buffer)))
1911 double period = 1.0F;
1913 for (op= callout_opt_list; op->name; op++)
1914 if (strncmpic(opt, op->name, Ustrlen(op->name)) == 0)
1917 verify_options |= op->flag;
1920 opt += Ustrlen(op->name);
1921 while (isspace(*opt)) opt++;
1924 *log_msgptr = string_sprintf("'=' expected after "
1925 "\"%s\" in ACL verify condition \"%s\"", op->name, arg);
1928 while (isspace(*opt)) opt++;
1932 period = readconf_readtime(opt, 0, FALSE);
1935 *log_msgptr = string_sprintf("bad time value in ACL condition "
1936 "\"verify %s\"", arg);
1943 case CALLOUT_DEFER_OK: callout_defer_ok = TRUE; break;
1944 case CALLOUT_POSTMASTER: pm_mailfrom = US""; break;
1945 case CALLOUT_FULLPOSTMASTER: pm_mailfrom = US""; break;
1946 case CALLOUT_MAILFROM:
1947 if (!verify_header_sender)
1949 *log_msgptr = string_sprintf("\"mailfrom\" is allowed as a "
1950 "callout option only for verify=header_sender (detected in ACL "
1951 "condition \"%s\")", arg);
1954 se_mailfrom = string_copy(opt);
1956 case CALLOUT_POSTMASTER_MAILFROM: pm_mailfrom = string_copy(opt); break;
1957 case CALLOUT_MAXWAIT: callout_overall = period; break;
1958 case CALLOUT_CONNECT: callout_connect = period; break;
1959 case CALLOUT_TIME: callout = period; break;
1965 *log_msgptr = string_sprintf("'=' expected after \"callout\" in "
1966 "ACL condition \"%s\"", arg);
1972 /* Option not recognized */
1976 *log_msgptr = string_sprintf("unknown option \"%s\" in ACL "
1977 "condition \"verify %s\"", ss, arg);
1982 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster)) ==
1983 (vopt_callout_recipsender|vopt_callout_recippmaster))
1985 *log_msgptr = US"only one of use_sender and use_postmaster can be set "
1986 "for a recipient callout";
1990 /* Handle sender-in-header verification. Default the user message to the log
1991 message if giving out verification details. */
1993 if (verify_header_sender)
1996 rc = verify_check_header_address(user_msgptr, log_msgptr, callout,
1997 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, verify_options,
2001 *basic_errno = verrno;
2002 if (smtp_return_error_details)
2004 if (*user_msgptr == NULL && *log_msgptr != NULL)
2005 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
2006 if (rc == DEFER) acl_temp_details = TRUE;
2011 /* Handle a sender address. The default is to verify *the* sender address, but
2012 optionally a different address can be given, for special requirements. If the
2013 address is empty, we are dealing with a bounce message that has no sender, so
2014 we cannot do any checking. If the real sender address gets rewritten during
2015 verification (e.g. DNS widening), set the flag to stop it being rewritten again
2016 during message reception.
2018 A list of verified "sender" addresses is kept to try to avoid doing to much
2019 work repetitively when there are multiple recipients in a message and they all
2020 require sender verification. However, when callouts are involved, it gets too
2021 complicated because different recipients may require different callout options.
2022 Therefore, we always do a full sender verify when any kind of callout is
2023 specified. Caching elsewhere, for instance in the DNS resolver and in the
2024 callout handling, should ensure that this is not terribly inefficient. */
2026 else if (verify_sender_address != NULL)
2028 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster))
2031 *log_msgptr = US"use_sender or use_postmaster cannot be used for a "
2032 "sender verify callout";
2036 sender_vaddr = verify_checked_sender(verify_sender_address);
2037 if (sender_vaddr != NULL && /* Previously checked */
2038 callout <= 0) /* No callout needed this time */
2040 /* If the "routed" flag is set, it means that routing worked before, so
2041 this check can give OK (the saved return code value, if set, belongs to a
2042 callout that was done previously). If the "routed" flag is not set, routing
2043 must have failed, so we use the saved return code. */
2045 if (testflag(sender_vaddr, af_verify_routed)) rc = OK; else
2047 rc = sender_vaddr->special_action;
2048 *basic_errno = sender_vaddr->basic_errno;
2050 HDEBUG(D_acl) debug_printf("using cached sender verify result\n");
2053 /* Do a new verification, and cache the result. The cache is used to avoid
2054 verifying the sender multiple times for multiple RCPTs when callouts are not
2055 specified (see comments above).
2057 The cache is also used on failure to give details in response to the first
2058 RCPT that gets bounced for this reason. However, this can be suppressed by
2059 the no_details option, which sets the flag that says "this detail has already
2060 been sent". The cache normally contains just one address, but there may be
2061 more in esoteric circumstances. */
2066 uschar *save_address_data = deliver_address_data;
2068 sender_vaddr = deliver_make_addr(verify_sender_address, TRUE);
2069 if (no_details) setflag(sender_vaddr, af_sverify_told);
2070 if (verify_sender_address[0] != 0)
2072 /* If this is the real sender address, save the unrewritten version
2073 for use later in receive. Otherwise, set a flag so that rewriting the
2074 sender in verify_address() does not update sender_address. */
2076 if (verify_sender_address == sender_address)
2077 sender_address_unrewritten = sender_address;
2079 verify_options |= vopt_fake_sender;
2081 if (success_on_redirect)
2082 verify_options |= vopt_success_on_redirect;
2084 /* The recipient, qualify, and expn options are never set in
2087 rc = verify_address(sender_vaddr, NULL, verify_options, callout,
2088 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, &routed);
2090 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
2094 if (Ustrcmp(sender_vaddr->address, verify_sender_address) != 0)
2096 DEBUG(D_acl) debug_printf("sender %s verified ok as %s\n",
2097 verify_sender_address, sender_vaddr->address);
2101 DEBUG(D_acl) debug_printf("sender %s verified ok\n",
2102 verify_sender_address);
2105 else *basic_errno = sender_vaddr->basic_errno;
2107 else rc = OK; /* Null sender */
2109 /* Cache the result code */
2111 if (routed) setflag(sender_vaddr, af_verify_routed);
2112 if (callout > 0) setflag(sender_vaddr, af_verify_callout);
2113 sender_vaddr->special_action = rc;
2114 sender_vaddr->next = sender_verified_list;
2115 sender_verified_list = sender_vaddr;
2117 /* Restore the recipient address data, which might have been clobbered by
2118 the sender verification. */
2120 deliver_address_data = save_address_data;
2123 /* Put the sender address_data value into $sender_address_data */
2125 sender_address_data = sender_vaddr->p.address_data;
2128 /* A recipient address just gets a straightforward verify; again we must handle
2129 the DEFER overrides. */
2135 if (success_on_redirect)
2136 verify_options |= vopt_success_on_redirect;
2138 /* We must use a copy of the address for verification, because it might
2142 rc = verify_address(&addr2, NULL, verify_options|vopt_is_recipient, callout,
2143 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, NULL);
2144 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
2146 *basic_errno = addr2.basic_errno;
2147 *log_msgptr = addr2.message;
2148 *user_msgptr = (addr2.user_message != NULL)?
2149 addr2.user_message : addr2.message;
2151 /* Allow details for temporary error if the address is so flagged. */
2152 if (testflag((&addr2), af_pass_message)) acl_temp_details = TRUE;
2154 /* Make $address_data visible */
2155 deliver_address_data = addr2.p.address_data;
2158 /* We have a result from the relevant test. Handle defer overrides first. */
2160 if (rc == DEFER && (defer_ok ||
2161 (callout_defer_ok && *basic_errno == ERRNO_CALLOUTDEFER)))
2163 HDEBUG(D_acl) debug_printf("verify defer overridden by %s\n",
2164 defer_ok? "defer_ok" : "callout_defer_ok");
2168 /* If we've failed a sender, set up a recipient message, and point
2169 sender_verified_failed to the address item that actually failed. */
2171 if (rc != OK && verify_sender_address != NULL)
2175 *log_msgptr = *user_msgptr = US"Sender verify failed";
2177 else if (*basic_errno != ERRNO_CALLOUTDEFER)
2179 *log_msgptr = *user_msgptr = US"Could not complete sender verify";
2183 *log_msgptr = US"Could not complete sender verify callout";
2184 *user_msgptr = smtp_return_error_details? sender_vaddr->user_message :
2188 sender_verified_failed = sender_vaddr;
2191 /* Verifying an address messes up the values of $domain and $local_part,
2192 so reset them before returning if this is a RCPT ACL. */
2196 deliver_domain = addr->domain;
2197 deliver_localpart = addr->local_part;
2201 /* Syntax errors in the verify argument come here. */
2204 *log_msgptr = string_sprintf("expected \"sender[=address]\", \"recipient\", "
2205 "\"helo\", \"header_syntax\", \"header_sender\" or "
2206 "\"reverse_host_lookup\" at start of ACL condition "
2207 "\"verify %s\"", arg);
2214 /*************************************************
2215 * Check argument for control= modifier *
2216 *************************************************/
2218 /* Called from acl_check_condition() below
2221 arg the argument string for control=
2222 pptr set to point to the terminating character
2223 where which ACL we are in
2224 log_msgptr for error messages
2226 Returns: CONTROL_xxx value
2230 decode_control(uschar *arg, uschar **pptr, int where, uschar **log_msgptr)
2235 for (d = controls_list;
2236 d < controls_list + sizeof(controls_list)/sizeof(control_def);
2239 len = Ustrlen(d->name);
2240 if (Ustrncmp(d->name, arg, len) == 0) break;
2243 if (d >= controls_list + sizeof(controls_list)/sizeof(control_def) ||
2244 (arg[len] != 0 && (!d->has_option || arg[len] != '/')))
2246 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
2247 return CONTROL_ERROR;
2257 /*************************************************
2258 * Return a ratelimit error *
2259 *************************************************/
2261 /* Called from acl_ratelimit() below
2264 log_msgptr for error messages
2265 format format string
2266 ... supplementary arguments
2267 ss ratelimit option name
2268 where ACL_WHERE_xxxx indicating which ACL this is
2274 ratelimit_error(uschar **log_msgptr, const char *format, ...)
2277 uschar buffer[STRING_SPRINTF_BUFFER_SIZE];
2278 va_start(ap, format);
2279 if (!string_vformat(buffer, sizeof(buffer), format, ap))
2280 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
2281 "string_sprintf expansion was longer than " SIZE_T_FMT, sizeof(buffer));
2283 *log_msgptr = string_sprintf(
2284 "error in arguments to \"ratelimit\" condition: %s", buffer);
2291 /*************************************************
2292 * Handle rate limiting *
2293 *************************************************/
2295 /* Called by acl_check_condition() below to calculate the result
2296 of the ACL ratelimit condition.
2298 Note that the return value might be slightly unexpected: if the
2299 sender's rate is above the limit then the result is OK. This is
2300 similar to the dnslists condition, and is so that you can write
2301 ACL clauses like: defer ratelimit = 15 / 1h
2304 arg the option string for ratelimit=
2305 where ACL_WHERE_xxxx indicating which ACL this is
2306 log_msgptr for error messages
2308 Returns: OK - Sender's rate is above limit
2309 FAIL - Sender's rate is below limit
2310 DEFER - Problem opening ratelimit database
2311 ERROR - Syntax error in options.
2315 acl_ratelimit(uschar *arg, int where, uschar **log_msgptr)
2317 double limit, period, count;
2320 uschar *unique = NULL;
2322 BOOL leaky = FALSE, strict = FALSE, readonly = FALSE;
2323 BOOL noupdate = FALSE, badacl = FALSE;
2324 int mode = RATE_PER_WHAT;
2326 tree_node **anchor, *t;
2327 open_db dbblock, *dbm;
2329 dbdata_ratelimit *dbd;
2330 dbdata_ratelimit_unique *dbdb;
2333 /* Parse the first two options and record their values in expansion
2334 variables. These variables allow the configuration to have informative
2335 error messages based on rate limits obtained from a table lookup. */
2337 /* First is the maximum number of messages per period / maximum burst
2338 size, which must be greater than or equal to zero. Zero is useful for
2339 rate measurement as opposed to rate limiting. */
2341 sender_rate_limit = string_nextinlist(&arg, &sep, NULL, 0);
2342 if (sender_rate_limit == NULL)
2346 limit = Ustrtod(sender_rate_limit, &ss);
2347 if (tolower(*ss) == 'k') { limit *= 1024.0; ss++; }
2348 else if (tolower(*ss) == 'm') { limit *= 1024.0*1024.0; ss++; }
2349 else if (tolower(*ss) == 'g') { limit *= 1024.0*1024.0*1024.0; ss++; }
2351 if (limit < 0.0 || *ss != '\0')
2352 return ratelimit_error(log_msgptr,
2353 "\"%s\" is not a positive number", sender_rate_limit);
2355 /* Second is the rate measurement period / exponential smoothing time
2356 constant. This must be strictly greater than zero, because zero leads to
2357 run-time division errors. */
2359 sender_rate_period = string_nextinlist(&arg, &sep, NULL, 0);
2360 if (sender_rate_period == NULL) period = -1.0;
2361 else period = readconf_readtime(sender_rate_period, 0, FALSE);
2363 return ratelimit_error(log_msgptr,
2364 "\"%s\" is not a time value", sender_rate_period);
2366 /* By default we are counting one of something, but the per_rcpt,
2367 per_byte, and count options can change this. */
2371 /* Parse the other options. */
2373 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2376 if (strcmpic(ss, US"leaky") == 0) leaky = TRUE;
2377 else if (strcmpic(ss, US"strict") == 0) strict = TRUE;
2378 else if (strcmpic(ss, US"noupdate") == 0) noupdate = TRUE;
2379 else if (strcmpic(ss, US"readonly") == 0) readonly = TRUE;
2380 else if (strcmpic(ss, US"per_cmd") == 0) RATE_SET(mode, PER_CMD);
2381 else if (strcmpic(ss, US"per_conn") == 0)
2383 RATE_SET(mode, PER_CONN);
2384 if (where == ACL_WHERE_NOTSMTP || where == ACL_WHERE_NOTSMTP_START)
2387 else if (strcmpic(ss, US"per_mail") == 0)
2389 RATE_SET(mode, PER_MAIL);
2390 if (where > ACL_WHERE_NOTSMTP) badacl = TRUE;
2392 else if (strcmpic(ss, US"per_rcpt") == 0)
2394 /* If we are running in the RCPT ACL, then we'll count the recipients
2395 one by one, but if we are running when we have accumulated the whole
2396 list then we'll add them all in one batch. */
2397 if (where == ACL_WHERE_RCPT)
2398 RATE_SET(mode, PER_RCPT);
2399 else if (where >= ACL_WHERE_PREDATA && where <= ACL_WHERE_NOTSMTP)
2400 RATE_SET(mode, PER_ALLRCPTS), count = (double)recipients_count;
2401 else if (where == ACL_WHERE_MAIL || where > ACL_WHERE_NOTSMTP)
2402 RATE_SET(mode, PER_RCPT), badacl = TRUE;
2404 else if (strcmpic(ss, US"per_byte") == 0)
2406 /* If we have not yet received the message data and there was no SIZE
2407 declaration on the MAIL comand, then it's safe to just use a value of
2408 zero and let the recorded rate decay as if nothing happened. */
2409 RATE_SET(mode, PER_MAIL);
2410 if (where > ACL_WHERE_NOTSMTP) badacl = TRUE;
2411 else count = message_size < 0 ? 0.0 : (double)message_size;
2413 else if (strcmpic(ss, US"per_addr") == 0)
2415 RATE_SET(mode, PER_RCPT);
2416 if (where != ACL_WHERE_RCPT) badacl = TRUE, unique = US"*";
2417 else unique = string_sprintf("%s@%s", deliver_localpart, deliver_domain);
2419 else if (strncmpic(ss, US"count=", 6) == 0)
2422 count = Ustrtod(ss+6, &e);
2423 if (count < 0.0 || *e != '\0')
2424 return ratelimit_error(log_msgptr,
2425 "\"%s\" is not a positive number", ss);
2427 else if (strncmpic(ss, US"unique=", 7) == 0)
2428 unique = string_copy(ss + 7);
2429 else if (key == NULL)
2430 key = string_copy(ss);
2432 key = string_sprintf("%s/%s", key, ss);
2435 /* Sanity check. When the badacl flag is set the update mode must either
2436 be readonly (which is the default if it is omitted) or, for backwards
2437 compatibility, a combination of noupdate and strict or leaky. */
2439 if (mode == RATE_PER_CLASH)
2440 return ratelimit_error(log_msgptr, "conflicting per_* options");
2441 if (leaky + strict + readonly > 1)
2442 return ratelimit_error(log_msgptr, "conflicting update modes");
2443 if (badacl && (leaky || strict) && !noupdate)
2444 return ratelimit_error(log_msgptr,
2445 "\"%s\" must not have /leaky or /strict option in %s ACL",
2446 ratelimit_option_string[mode], acl_wherenames[where]);
2448 /* Set the default values of any unset options. In readonly mode we
2449 perform the rate computation without any increment so that its value
2450 decays to eventually allow over-limit senders through. */
2452 if (noupdate) readonly = TRUE, leaky = strict = FALSE;
2453 if (badacl) readonly = TRUE;
2454 if (readonly) count = 0.0;
2455 if (!strict && !readonly) leaky = TRUE;
2456 if (mode == RATE_PER_WHAT) mode = RATE_PER_MAIL;
2458 /* Create the lookup key. If there is no explicit key, use sender_host_address.
2459 If there is no sender_host_address (e.g. -bs or acl_not_smtp) then we simply
2460 omit it. The smoothing constant (sender_rate_period) and the per_xxx options
2461 are added to the key because they alter the meaning of the stored data. */
2464 key = (sender_host_address == NULL)? US"" : sender_host_address;
2466 key = string_sprintf("%s/%s/%s%s",
2468 ratelimit_option_string[mode],
2469 unique == NULL ? "" : "unique/",
2473 debug_printf("ratelimit condition count=%.0f %.1f/%s\n", count, limit, key);
2475 /* See if we have already computed the rate by looking in the relevant tree.
2476 For per-connection rate limiting, store tree nodes and dbdata in the permanent
2477 pool so that they survive across resets. In readonly mode we only remember the
2478 result for the rest of this command in case a later command changes it. After
2479 this bit of logic the code is independent of the per_* mode. */
2481 old_pool = store_pool;
2484 anchor = &ratelimiters_cmd;
2487 anchor = &ratelimiters_conn;
2488 store_pool = POOL_PERM;
2492 case RATE_PER_ALLRCPTS:
2493 anchor = &ratelimiters_mail;
2498 anchor = &ratelimiters_cmd;
2501 anchor = NULL; /* silence an "unused" complaint */
2502 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
2503 "internal ACL error: unknown ratelimit mode %d", mode);
2507 t = tree_search(*anchor, key);
2511 /* The following few lines duplicate some of the code below. */
2512 rc = (dbd->rate < limit)? FAIL : OK;
2513 store_pool = old_pool;
2514 sender_rate = string_sprintf("%.1f", dbd->rate);
2516 debug_printf("ratelimit found pre-computed rate %s\n", sender_rate);
2520 /* We aren't using a pre-computed rate, so get a previously recorded rate
2521 from the database, which will be updated and written back if required. */
2523 dbm = dbfn_open(US"ratelimit", O_RDWR, &dbblock, TRUE);
2526 store_pool = old_pool;
2528 HDEBUG(D_acl) debug_printf("ratelimit database not available\n");
2529 *log_msgptr = US"ratelimit database not available";
2532 dbdb = dbfn_read_with_length(dbm, key, &dbdb_size);
2535 gettimeofday(&tv, NULL);
2539 /* Locate the basic ratelimit block inside the DB data. */
2540 HDEBUG(D_acl) debug_printf("ratelimit found key in database\n");
2543 /* Forget the old Bloom filter if it is too old, so that we count each
2544 repeating event once per period. We don't simply clear and re-use the old
2545 filter because we want its size to change if the limit changes. Note that
2546 we keep the dbd pointer for copying the rate into the new data block. */
2548 if(unique != NULL && tv.tv_sec > dbdb->bloom_epoch + period)
2550 HDEBUG(D_acl) debug_printf("ratelimit discarding old Bloom filter\n");
2556 if(unique != NULL && dbdb_size < sizeof(*dbdb))
2558 HDEBUG(D_acl) debug_printf("ratelimit discarding undersize Bloom filter\n");
2563 /* Allocate a new data block if the database lookup failed
2564 or the Bloom filter passed its age limit. */
2570 /* No Bloom filter. This basic ratelimit block is initialized below. */
2571 HDEBUG(D_acl) debug_printf("ratelimit creating new rate data block\n");
2572 dbdb_size = sizeof(*dbd);
2573 dbdb = store_get(dbdb_size);
2578 HDEBUG(D_acl) debug_printf("ratelimit creating new Bloom filter\n");
2580 /* See the long comment below for an explanation of the magic number 2.
2581 The filter has a minimum size in case the rate limit is very small;
2582 this is determined by the definition of dbdata_ratelimit_unique. */
2584 extra = (int)limit * 2 - sizeof(dbdb->bloom);
2585 if (extra < 0) extra = 0;
2586 dbdb_size = sizeof(*dbdb) + extra;
2587 dbdb = store_get(dbdb_size);
2588 dbdb->bloom_epoch = tv.tv_sec;
2589 dbdb->bloom_size = sizeof(dbdb->bloom) + extra;
2590 memset(dbdb->bloom, 0, dbdb->bloom_size);
2592 /* Preserve any basic ratelimit data (which is our longer-term memory)
2593 by copying it from the discarded block. */
2603 /* If we are counting unique events, find out if this event is new or not.
2604 If the client repeats the event during the current period then it should be
2605 counted. We skip this code in readonly mode for efficiency, because any
2606 changes to the filter will be discarded and because count is already set to
2609 if (unique != NULL && !readonly)
2611 /* We identify unique events using a Bloom filter. (You can find my
2612 notes on Bloom filters at http://fanf.livejournal.com/81696.html)
2613 With the per_addr option, an "event" is a recipient address, though the
2614 user can use the unique option to define their own events. We only count
2615 an event if we have not seen it before.
2617 We size the filter according to the rate limit, which (in leaky mode)
2618 is the limit on the population of the filter. We allow 16 bits of space
2619 per entry (see the construction code above) and we set (up to) 8 of them
2620 when inserting an element (see the loop below). The probability of a false
2621 positive (an event we have not seen before but which we fail to count) is
2625 allzero = exp(-numhash * pop / size)
2626 = exp(-0.5 * pop / limit)
2627 fpr = pow(1 - allzero, numhash)
2629 For senders at the limit the fpr is 0.06% or 1 in 1700
2630 and for senders at half the limit it is 0.0006% or 1 in 170000
2632 In strict mode the Bloom filter can fill up beyond the normal limit, in
2633 which case the false positive rate will rise. This means that the
2634 measured rate for very fast senders can bogusly drop off after a while.
2636 At twice the limit, the fpr is 2.5% or 1 in 40
2637 At four times the limit, it is 31% or 1 in 3.2
2639 It takes ln(pop/limit) periods for an over-limit burst of pop events to
2640 decay below the limit, and if this is more than one then the Bloom filter
2641 will be discarded before the decay gets that far. The false positive rate
2642 at this threshold is 9.3% or 1 in 10.7. */
2645 unsigned n, hash, hinc;
2649 /* Instead of using eight independent hash values, we combine two values
2650 using the formula h1 + n * h2. This does not harm the Bloom filter's
2651 performance, and means the amount of hash we need is independent of the
2652 number of bits we set in the filter. */
2654 md5_start(&md5info);
2655 md5_end(&md5info, unique, Ustrlen(unique), md5sum);
2656 hash = md5sum[0] | md5sum[1] << 8 | md5sum[2] << 16 | md5sum[3] << 24;
2657 hinc = md5sum[4] | md5sum[5] << 8 | md5sum[6] << 16 | md5sum[7] << 24;
2659 /* Scan the bits corresponding to this event. A zero bit means we have
2660 not seen it before. Ensure all bits are set to record this event. */
2662 HDEBUG(D_acl) debug_printf("ratelimit checking uniqueness of %s\n", unique);
2665 for (n = 0; n < 8; n++, hash += hinc)
2667 int bit = 1 << (hash % 8);
2668 int byte = (hash / 8) % dbdb->bloom_size;
2669 if ((dbdb->bloom[byte] & bit) == 0)
2671 dbdb->bloom[byte] |= bit;
2676 /* If this event has occurred before, do not count it. */
2680 HDEBUG(D_acl) debug_printf("ratelimit event found in Bloom filter\n");
2684 HDEBUG(D_acl) debug_printf("ratelimit event added to Bloom filter\n");
2687 /* If there was no previous ratelimit data block for this key, initialize
2688 the new one, otherwise update the block from the database. The initial rate
2689 is what would be computed by the code below for an infinite interval. */
2693 HDEBUG(D_acl) debug_printf("ratelimit initializing new key's rate data\n");
2695 dbd->time_stamp = tv.tv_sec;
2696 dbd->time_usec = tv.tv_usec;
2701 /* The smoothed rate is computed using an exponentially weighted moving
2702 average adjusted for variable sampling intervals. The standard EWMA for
2703 a fixed sampling interval is: f'(t) = (1 - a) * f(t) + a * f'(t - 1)
2704 where f() is the measured value and f'() is the smoothed value.
2706 Old data decays out of the smoothed value exponentially, such that data n
2707 samples old is multiplied by a^n. The exponential decay time constant p
2708 is defined such that data p samples old is multiplied by 1/e, which means
2709 that a = exp(-1/p). We can maintain the same time constant for a variable
2710 sampling interval i by using a = exp(-i/p).
2712 The rate we are measuring is messages per period, suitable for directly
2713 comparing with the limit. The average rate between now and the previous
2714 message is period / interval, which we feed into the EWMA as the sample.
2716 It turns out that the number of messages required for the smoothed rate
2717 to reach the limit when they are sent in a burst is equal to the limit.
2718 This can be seen by analysing the value of the smoothed rate after N
2719 messages sent at even intervals. Let k = (1 - a) * p/i
2721 rate_1 = (1 - a) * p/i + a * rate_0
2723 rate_2 = k + a * rate_1
2724 = k + a * k + a^2 * rate_0
2725 rate_3 = k + a * k + a^2 * k + a^3 * rate_0
2726 rate_N = rate_0 * a^N + k * SUM(x=0..N-1)(a^x)
2727 = rate_0 * a^N + k * (1 - a^N) / (1 - a)
2728 = rate_0 * a^N + p/i * (1 - a^N)
2730 When N is large, a^N -> 0 so rate_N -> p/i as desired.
2732 rate_N = p/i + (rate_0 - p/i) * a^N
2733 a^N = (rate_N - p/i) / (rate_0 - p/i)
2734 N * -i/p = log((rate_N - p/i) / (rate_0 - p/i))
2735 N = p/i * log((rate_0 - p/i) / (rate_N - p/i))
2737 Numerical analysis of the above equation, setting the computed rate to
2738 increase from rate_0 = 0 to rate_N = limit, shows that for large sending
2739 rates, p/i, the number of messages N = limit. So limit serves as both the
2740 maximum rate measured in messages per period, and the maximum number of
2741 messages that can be sent in a fast burst. */
2743 double this_time = (double)tv.tv_sec
2744 + (double)tv.tv_usec / 1000000.0;
2745 double prev_time = (double)dbd->time_stamp
2746 + (double)dbd->time_usec / 1000000.0;
2748 /* We must avoid division by zero, and deal gracefully with the clock going
2749 backwards. If we blunder ahead when time is in reverse then the computed
2750 rate will be bogus. To be safe we clamp interval to a very small number. */
2752 double interval = this_time - prev_time <= 0.0 ? 1e-9
2753 : this_time - prev_time;
2755 double i_over_p = interval / period;
2756 double a = exp(-i_over_p);
2758 /* Combine the instantaneous rate (period / interval) with the previous rate
2759 using the smoothing factor a. In order to measure sized events, multiply the
2760 instantaneous rate by the count of bytes or recipients etc. */
2762 dbd->time_stamp = tv.tv_sec;
2763 dbd->time_usec = tv.tv_usec;
2764 dbd->rate = (1 - a) * count / i_over_p + a * dbd->rate;
2766 /* When events are very widely spaced the computed rate tends towards zero.
2767 Although this is accurate it turns out not to be useful for our purposes,
2768 especially when the first event after a long silence is the start of a spam
2769 run. A more useful model is that the rate for an isolated event should be the
2770 size of the event per the period size, ignoring the lack of events outside
2771 the current period and regardless of where the event falls in the period. So,
2772 if the interval was so long that the calculated rate is unhelpfully small, we
2773 re-intialize the rate. In the absence of higher-rate bursts, the condition
2774 below is true if the interval is greater than the period. */
2776 if (dbd->rate < count) dbd->rate = count;
2779 /* Clients sending at the limit are considered to be over the limit.
2780 This matters for edge cases such as a limit of zero, when the client
2781 should be completely blocked. */
2783 rc = (dbd->rate < limit)? FAIL : OK;
2785 /* Update the state if the rate is low or if we are being strict. If we
2786 are in leaky mode and the sender's rate is too high, we do not update
2787 the recorded rate in order to avoid an over-aggressive sender's retry
2788 rate preventing them from getting any email through. If readonly is set,
2789 neither leaky nor strict are set, so we do not do any updates. */
2791 if ((rc == FAIL && leaky) || strict)
2793 dbfn_write(dbm, key, dbdb, dbdb_size);
2794 HDEBUG(D_acl) debug_printf("ratelimit db updated\n");
2798 HDEBUG(D_acl) debug_printf("ratelimit db not updated: %s\n",
2799 readonly? "readonly mode" : "over the limit, but leaky");
2804 /* Store the result in the tree for future reference. */
2806 t = store_get(sizeof(tree_node) + Ustrlen(key));
2808 Ustrcpy(t->name, key);
2809 (void)tree_insertnode(anchor, t);
2811 /* We create the formatted version of the sender's rate very late in
2812 order to ensure that it is done using the correct storage pool. */
2814 store_pool = old_pool;
2815 sender_rate = string_sprintf("%.1f", dbd->rate);
2818 debug_printf("ratelimit computed rate %s\n", sender_rate);
2825 /*************************************************
2826 * The udpsend ACL modifier *
2827 *************************************************/
2829 /* Called by acl_check_condition() below.
2832 arg the option string for udpsend=
2833 log_msgptr for error messages
2835 Returns: OK - Completed.
2836 DEFER - Problem with DNS lookup.
2837 ERROR - Syntax error in options.
2841 acl_udpsend(uschar *arg, uschar **log_msgptr)
2853 hostname = string_nextinlist(&arg, &sep, NULL, 0);
2854 portstr = string_nextinlist(&arg, &sep, NULL, 0);
2856 if (hostname == NULL)
2858 *log_msgptr = US"missing destination host in \"udpsend\" modifier";
2861 if (portstr == NULL)
2863 *log_msgptr = US"missing destination port in \"udpsend\" modifier";
2868 *log_msgptr = US"missing datagram payload in \"udpsend\" modifier";
2871 portnum = Ustrtol(portstr, &portend, 10);
2872 if (*portend != '\0')
2874 *log_msgptr = US"bad destination port in \"udpsend\" modifier";
2878 /* Make a single-item host list. */
2879 h = store_get(sizeof(host_item));
2880 memset(h, 0, sizeof(host_item));
2885 if (string_is_ip_address(hostname, NULL))
2886 h->address = hostname, r = HOST_FOUND;
2888 r = host_find_byname(h, NULL, 0, NULL, FALSE);
2889 if (r == HOST_FIND_FAILED || r == HOST_FIND_AGAIN)
2891 *log_msgptr = US"DNS lookup failed in \"udpsend\" modifier";
2896 debug_printf("udpsend [%s]:%d %s\n", h->address, portnum, arg);
2898 host_af = (Ustrchr(h->address, ':') == NULL)? AF_INET:AF_INET6;
2899 r = s = ip_socket(SOCK_DGRAM, host_af);
2900 if (r < 0) goto defer;
2901 r = ip_connect(s, host_af, h->address, portnum, 1);
2902 if (r < 0) goto defer;
2904 r = send(s, arg, len, MSG_NOSIGNAL);
2905 if (r < 0) goto defer;
2909 string_sprintf("\"udpsend\" truncated from %d to %d octets", len, r);
2914 debug_printf("udpsend %d bytes\n", r);
2919 *log_msgptr = string_sprintf("\"udpsend\" failed: %s", strerror(errno));
2925 /*************************************************
2926 * Handle conditions/modifiers on an ACL item *
2927 *************************************************/
2929 /* Called from acl_check() below.
2933 cb ACL condition block - if NULL, result is OK
2934 where where called from
2935 addr the address being checked for RCPT, or NULL
2936 level the nesting level
2937 epp pointer to pass back TRUE if "endpass" encountered
2938 (applies only to "accept" and "discard")
2939 user_msgptr user message pointer
2940 log_msgptr log message pointer
2941 basic_errno pointer to where to put verify error
2943 Returns: OK - all conditions are met
2944 DISCARD - an "acl" condition returned DISCARD - only allowed
2945 for "accept" or "discard" verbs
2946 FAIL - at least one condition fails
2947 FAIL_DROP - an "acl" condition returned FAIL_DROP
2948 DEFER - can't tell at the moment (typically, lookup defer,
2949 but can be temporary callout problem)
2950 ERROR - ERROR from nested ACL or expansion failure or other
2955 acl_check_condition(int verb, acl_condition_block *cb, int where,
2956 address_item *addr, int level, BOOL *epp, uschar **user_msgptr,
2957 uschar **log_msgptr, int *basic_errno)
2959 uschar *user_message = NULL;
2960 uschar *log_message = NULL;
2961 uschar *debug_tag = NULL;
2962 uschar *debug_opts = NULL;
2965 #ifdef WITH_CONTENT_SCAN
2969 for (; cb != NULL; cb = cb->next)
2974 /* The message and log_message items set up messages to be used in
2975 case of rejection. They are expanded later. */
2977 if (cb->type == ACLC_MESSAGE)
2979 user_message = cb->arg;
2983 if (cb->type == ACLC_LOG_MESSAGE)
2985 log_message = cb->arg;
2989 /* The endpass "condition" just sets a flag to show it occurred. This is
2990 checked at compile time to be on an "accept" or "discard" item. */
2992 if (cb->type == ACLC_ENDPASS)
2998 /* For other conditions and modifiers, the argument is expanded now for some
2999 of them, but not for all, because expansion happens down in some lower level
3000 checking functions in some cases. */
3002 if (cond_expand_at_top[cb->type])
3004 arg = expand_string(cb->arg);
3007 if (expand_string_forcedfail) continue;
3008 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s",
3009 cb->arg, expand_string_message);
3010 return search_find_defer? DEFER : ERROR;
3015 /* Show condition, and expanded condition if it's different */
3020 debug_printf("check %s%s %n",
3021 (!cond_modifiers[cb->type] && cb->u.negated)? "!":"",
3022 conditions[cb->type], &lhswidth);
3024 if (cb->type == ACLC_SET)
3026 debug_printf("acl_%s ", cb->u.varname);
3027 lhswidth += 5 + Ustrlen(cb->u.varname);
3030 debug_printf("= %s\n", cb->arg);
3033 debug_printf("%.*s= %s\n", lhswidth,
3037 /* Check that this condition makes sense at this time */
3039 if ((cond_forbids[cb->type] & (1 << where)) != 0)
3041 *log_msgptr = string_sprintf("cannot %s %s condition in %s ACL",
3042 cond_modifiers[cb->type]? "use" : "test",
3043 conditions[cb->type], acl_wherenames[where]);
3047 /* Run the appropriate test for each condition, or take the appropriate
3048 action for the remaining modifiers. */
3052 case ACLC_ADD_HEADER:
3056 /* A nested ACL that returns "discard" makes sense only for an "accept" or
3060 rc = acl_check_wargs(where, addr, arg, level+1, user_msgptr, log_msgptr);
3061 if (rc == DISCARD && verb != ACL_ACCEPT && verb != ACL_DISCARD)
3063 *log_msgptr = string_sprintf("nested ACL returned \"discard\" for "
3064 "\"%s\" command (only allowed with \"accept\" or \"discard\")",
3070 case ACLC_AUTHENTICATED:
3071 rc = (sender_host_authenticated == NULL)? FAIL :
3072 match_isinlist(sender_host_authenticated, &arg, 0, NULL, NULL, MCL_STRING,
3076 #ifdef EXPERIMENTAL_BRIGHTMAIL
3077 case ACLC_BMI_OPTIN:
3079 int old_pool = store_pool;
3080 store_pool = POOL_PERM;
3081 bmi_current_optin = string_copy(arg);
3082 store_pool = old_pool;
3087 case ACLC_CONDITION:
3088 /* The true/false parsing here should be kept in sync with that used in
3089 expand.c when dealing with ECOND_BOOL so that we don't have too many
3090 different definitions of what can be a boolean. */
3091 if (Ustrspn(arg, "0123456789") == Ustrlen(arg)) /* Digits, or empty */
3092 rc = (Uatoi(arg) == 0)? FAIL : OK;
3094 rc = (strcmpic(arg, US"no") == 0 ||
3095 strcmpic(arg, US"false") == 0)? FAIL :
3096 (strcmpic(arg, US"yes") == 0 ||
3097 strcmpic(arg, US"true") == 0)? OK : DEFER;
3099 *log_msgptr = string_sprintf("invalid \"condition\" value \"%s\"", arg);
3102 case ACLC_CONTINUE: /* Always succeeds */
3106 control_type = decode_control(arg, &p, where, log_msgptr);
3108 /* Check if this control makes sense at this time */
3110 if ((control_forbids[control_type] & (1 << where)) != 0)
3112 *log_msgptr = string_sprintf("cannot use \"control=%s\" in %s ACL",
3113 controls[control_type], acl_wherenames[where]);
3117 switch(control_type)
3119 case CONTROL_AUTH_UNADVERTISED:
3120 allow_auth_unadvertised = TRUE;
3123 #ifdef EXPERIMENTAL_BRIGHTMAIL
3124 case CONTROL_BMI_RUN:
3129 #ifndef DISABLE_DKIM
3130 case CONTROL_DKIM_VERIFY:
3131 dkim_disable_verify = TRUE;
3132 #ifdef EXPERIMENTAL_DMARC
3133 /* Since DKIM was blocked, skip DMARC too */
3134 dmarc_disable_verify = TRUE;
3135 dmarc_enable_forensic = FALSE;
3140 #ifdef EXPERIMENTAL_DMARC
3141 case CONTROL_DMARC_VERIFY:
3142 dmarc_disable_verify = TRUE;
3145 case CONTROL_DMARC_FORENSIC:
3146 dmarc_enable_forensic = TRUE;
3153 int fd, af, level, optname, value;
3154 /* If we are acting on stdin, the setsockopt may fail if stdin is not
3155 a socket; we can accept that, we'll just debug-log failures anyway. */
3156 fd = fileno(smtp_in);
3157 af = ip_get_address_family(fd);
3161 debug_printf("smtp input is probably not a socket [%s], not setting DSCP\n",
3165 if (dscp_lookup(p+1, af, &level, &optname, &value))
3167 if (setsockopt(fd, level, optname, &value, sizeof(value)) < 0)
3169 HDEBUG(D_acl) debug_printf("failed to set input DSCP[%s]: %s\n",
3170 p+1, strerror(errno));
3174 HDEBUG(D_acl) debug_printf("set input DSCP to \"%s\"\n", p+1);
3179 *log_msgptr = string_sprintf("unrecognised DSCP value in \"control=%s\"", arg);
3185 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3193 case CONTROL_CASEFUL_LOCAL_PART:
3194 deliver_localpart = addr->cc_local_part;
3197 case CONTROL_CASELOWER_LOCAL_PART:
3198 deliver_localpart = addr->lc_local_part;
3201 case CONTROL_ENFORCE_SYNC:
3202 smtp_enforce_sync = TRUE;
3205 case CONTROL_NO_ENFORCE_SYNC:
3206 smtp_enforce_sync = FALSE;
3209 #ifdef WITH_CONTENT_SCAN
3210 case CONTROL_NO_MBOX_UNSPOOL:
3211 no_mbox_unspool = TRUE;
3215 case CONTROL_NO_MULTILINE:
3216 no_multiline_responses = TRUE;
3219 case CONTROL_NO_PIPELINING:
3220 pipelining_enable = FALSE;
3223 case CONTROL_NO_DELAY_FLUSH:
3224 disable_delay_flush = TRUE;
3227 case CONTROL_NO_CALLOUT_FLUSH:
3228 disable_callout_flush = TRUE;
3231 case CONTROL_FAKEDEFER:
3232 case CONTROL_FAKEREJECT:
3233 fake_response = (control_type == CONTROL_FAKEDEFER) ? DEFER : FAIL;
3237 while (*pp != 0) pp++;
3238 fake_response_text = expand_string(string_copyn(p+1, pp-p-1));
3243 /* Explicitly reset to default string */
3244 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).";
3248 case CONTROL_FREEZE:
3249 deliver_freeze = TRUE;
3250 deliver_frozen_at = time(NULL);
3251 freeze_tell = freeze_tell_config; /* Reset to configured value */
3252 if (Ustrncmp(p, "/no_tell", 8) == 0)
3259 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3264 case CONTROL_QUEUE_ONLY:
3265 queue_only_policy = TRUE;
3268 case CONTROL_SUBMISSION:
3269 originator_name = US"";
3270 submission_mode = TRUE;
3273 if (Ustrncmp(p, "/sender_retain", 14) == 0)
3276 active_local_sender_retain = TRUE;
3277 active_local_from_check = FALSE;
3279 else if (Ustrncmp(p, "/domain=", 8) == 0)
3282 while (*pp != 0 && *pp != '/') pp++;
3283 submission_domain = string_copyn(p+8, pp-p-8);
3286 /* The name= option must be last, because it swallows the rest of
3288 else if (Ustrncmp(p, "/name=", 6) == 0)
3291 while (*pp != 0) pp++;
3292 submission_name = string_copy(parse_fix_phrase(p+6, pp-p-6,
3293 big_buffer, big_buffer_size));
3300 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3308 if (Ustrncmp(p, "/tag=", 5) == 0)
3311 while (*pp != '\0' && *pp != '/') pp++;
3312 debug_tag = string_copyn(p+5, pp-p-5);
3315 else if (Ustrncmp(p, "/opts=", 6) == 0)
3318 while (*pp != '\0' && *pp != '/') pp++;
3319 debug_opts = string_copyn(p+6, pp-p-6);
3323 debug_logging_activate(debug_tag, debug_opts);
3326 case CONTROL_SUPPRESS_LOCAL_FIXUPS:
3327 suppress_local_fixups = TRUE;
3330 case CONTROL_CUTTHROUGH_DELIVERY:
3333 *log_msgptr = string_sprintf("\"control=%s\" on frozen item", arg);
3336 if (queue_only_policy)
3338 *log_msgptr = string_sprintf("\"control=%s\" on queue-only item", arg);
3341 cutthrough_delivery = TRUE;
3346 #ifdef EXPERIMENTAL_DCC
3349 /* Seperate the regular expression and any optional parameters. */
3350 uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size);
3351 /* Run the dcc backend. */
3352 rc = dcc_process(&ss);
3353 /* Modify return code based upon the existance of options. */
3354 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
3356 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
3358 /* FAIL so that the message is passed to the next ACL */
3366 #ifdef WITH_CONTENT_SCAN
3368 rc = mime_decode(&arg);
3374 int delay = readconf_readtime(arg, 0, FALSE);
3377 *log_msgptr = string_sprintf("syntax error in argument for \"delay\" "
3378 "modifier: \"%s\" is not a time value", arg);
3383 HDEBUG(D_acl) debug_printf("delay modifier requests %d-second delay\n",
3388 debug_printf("delay skipped in -bh checking mode\n");
3391 /* It appears to be impossible to detect that a TCP/IP connection has
3392 gone away without reading from it. This means that we cannot shorten
3393 the delay below if the client goes away, because we cannot discover
3394 that the client has closed its end of the connection. (The connection
3395 is actually in a half-closed state, waiting for the server to close its
3396 end.) It would be nice to be able to detect this state, so that the
3397 Exim process is not held up unnecessarily. However, it seems that we
3398 can't. The poll() function does not do the right thing, and in any case
3399 it is not always available.
3401 NOTE 1: If ever this state of affairs changes, remember that we may be
3402 dealing with stdin/stdout here, in addition to TCP/IP connections.
3403 Also, delays may be specified for non-SMTP input, where smtp_out and
3404 smtp_in will be NULL. Whatever is done must work in all cases.
3406 NOTE 2: The added feature of flushing the output before a delay must
3407 apply only to SMTP input. Hence the test for smtp_out being non-NULL.
3412 if (smtp_out != NULL && !disable_delay_flush) mac_smtp_fflush();
3413 while (delay > 0) delay = sleep(delay);
3419 #ifdef WITH_OLD_DEMIME
3425 #ifndef DISABLE_DKIM
3426 case ACLC_DKIM_SIGNER:
3427 if (dkim_cur_signer != NULL)
3428 rc = match_isinlist(dkim_cur_signer,
3429 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
3434 case ACLC_DKIM_STATUS:
3435 rc = match_isinlist(dkim_exim_expand_query(DKIM_VERIFY_STATUS),
3436 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
3440 #ifdef EXPERIMENTAL_DMARC
3441 case ACLC_DMARC_STATUS:
3442 if (!dmarc_has_been_checked)
3444 dmarc_has_been_checked = TRUE;
3445 /* used long way of dmarc_exim_expand_query() in case we need more
3446 * view into the process in the future. */
3447 rc = match_isinlist(dmarc_exim_expand_query(DMARC_VERIFY_STATUS),
3448 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
3453 rc = verify_check_dnsbl(&arg);
3457 rc = match_isinlist(addr->domain, &arg, 0, &domainlist_anchor,
3458 addr->domain_cache, MCL_DOMAIN, TRUE, &deliver_domain_data);
3461 /* The value in tls_cipher is the full cipher name, for example,
3462 TLSv1:DES-CBC3-SHA:168, whereas the values to test for are just the
3463 cipher names such as DES-CBC3-SHA. But program defensively. We don't know
3464 what may in practice come out of the SSL library - which at the time of
3465 writing is poorly documented. */
3467 case ACLC_ENCRYPTED:
3468 if (tls_in.cipher == NULL) rc = FAIL; else
3470 uschar *endcipher = NULL;
3471 uschar *cipher = Ustrchr(tls_in.cipher, ':');
3472 if (cipher == NULL) cipher = tls_in.cipher; else
3474 endcipher = Ustrchr(++cipher, ':');
3475 if (endcipher != NULL) *endcipher = 0;
3477 rc = match_isinlist(cipher, &arg, 0, NULL, NULL, MCL_STRING, TRUE, NULL);
3478 if (endcipher != NULL) *endcipher = ':';
3482 /* Use verify_check_this_host() instead of verify_check_host() so that
3483 we can pass over &host_data to catch any looked up data. Once it has been
3484 set, it retains its value so that it's still there if another ACL verb
3485 comes through here and uses the cache. However, we must put it into
3486 permanent store in case it is also expected to be used in a subsequent
3487 message in the same SMTP connection. */
3490 rc = verify_check_this_host(&arg, sender_host_cache, NULL,
3491 (sender_host_address == NULL)? US"" : sender_host_address, &host_data);
3492 if (host_data != NULL) host_data = string_copy_malloc(host_data);
3495 case ACLC_LOCAL_PARTS:
3496 rc = match_isinlist(addr->cc_local_part, &arg, 0,
3497 &localpartlist_anchor, addr->localpart_cache, MCL_LOCALPART, TRUE,
3498 &deliver_localpart_data);
3501 case ACLC_LOG_REJECT_TARGET:
3507 while ((ss = string_nextinlist(&s, &sep, big_buffer, big_buffer_size))
3510 if (Ustrcmp(ss, "main") == 0) logbits |= LOG_MAIN;
3511 else if (Ustrcmp(ss, "panic") == 0) logbits |= LOG_PANIC;
3512 else if (Ustrcmp(ss, "reject") == 0) logbits |= LOG_REJECT;
3515 logbits |= LOG_MAIN|LOG_REJECT;
3516 log_write(0, LOG_MAIN|LOG_PANIC, "unknown log name \"%s\" in "
3517 "\"log_reject_target\" in %s ACL", ss, acl_wherenames[where]);
3520 log_reject_target = logbits;
3533 if (Ustrncmp(s, "main", 4) == 0)
3534 { logbits |= LOG_MAIN; s += 4; }
3535 else if (Ustrncmp(s, "panic", 5) == 0)
3536 { logbits |= LOG_PANIC; s += 5; }
3537 else if (Ustrncmp(s, "reject", 6) == 0)
3538 { logbits |= LOG_REJECT; s += 6; }
3541 logbits = LOG_MAIN|LOG_PANIC;
3542 s = string_sprintf(":unknown log name in \"%s\" in "
3543 "\"logwrite\" in %s ACL", arg, acl_wherenames[where]);
3549 while (isspace(*s)) s++;
3552 if (logbits == 0) logbits = LOG_MAIN;
3553 log_write(0, logbits, "%s", string_printing(s));
3557 #ifdef WITH_CONTENT_SCAN
3560 /* Separate the regular expression and any optional parameters. */
3561 uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size);
3562 /* Run the malware backend. */
3564 /* Modify return code based upon the existance of options. */
3565 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
3567 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
3569 /* FAIL so that the message is passed to the next ACL */
3576 case ACLC_MIME_REGEX:
3577 rc = mime_regex(&arg);
3581 case ACLC_RATELIMIT:
3582 rc = acl_ratelimit(arg, where, log_msgptr);
3585 case ACLC_RECIPIENTS:
3586 rc = match_address_list(addr->address, TRUE, TRUE, &arg, NULL, -1, 0,
3590 #ifdef WITH_CONTENT_SCAN
3596 case ACLC_REMOVE_HEADER:
3597 setup_remove_header(arg);
3600 case ACLC_SENDER_DOMAINS:
3603 sdomain = Ustrrchr(sender_address, '@');
3604 sdomain = (sdomain == NULL)? US"" : sdomain + 1;
3605 rc = match_isinlist(sdomain, &arg, 0, &domainlist_anchor,
3606 sender_domain_cache, MCL_DOMAIN, TRUE, NULL);
3611 rc = match_address_list(sender_address, TRUE, TRUE, &arg,
3612 sender_address_cache, -1, 0, &sender_data);
3615 /* Connection variables must persist forever */
3619 int old_pool = store_pool;
3620 if (cb->u.varname[0] == 'c') store_pool = POOL_PERM;
3621 acl_var_create(cb->u.varname)->data.ptr = string_copy(arg);
3622 store_pool = old_pool;
3626 #ifdef WITH_CONTENT_SCAN
3629 /* Seperate the regular expression and any optional parameters. */
3630 uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size);
3631 /* Run the spam backend. */
3633 /* Modify return code based upon the existance of options. */
3634 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
3636 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
3638 /* FAIL so that the message is passed to the next ACL */
3646 #ifdef EXPERIMENTAL_SPF
3648 rc = spf_process(&arg, sender_address, SPF_PROCESS_NORMAL);
3650 case ACLC_SPF_GUESS:
3651 rc = spf_process(&arg, sender_address, SPF_PROCESS_GUESS);
3656 rc = acl_udpsend(arg, log_msgptr);
3659 /* If the verb is WARN, discard any user message from verification, because
3660 such messages are SMTP responses, not header additions. The latter come
3661 only from explicit "message" modifiers. However, put the user message into
3662 $acl_verify_message so it can be used in subsequent conditions or modifiers
3663 (until something changes it). */
3666 rc = acl_verify(where, addr, arg, user_msgptr, log_msgptr, basic_errno);
3667 acl_verify_message = *user_msgptr;
3668 if (verb == ACL_WARN) *user_msgptr = NULL;
3672 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown "
3673 "condition %d", cb->type);
3677 /* If a condition was negated, invert OK/FAIL. */
3679 if (!cond_modifiers[cb->type] && cb->u.negated)
3681 if (rc == OK) rc = FAIL;
3682 else if (rc == FAIL || rc == FAIL_DROP) rc = OK;
3685 if (rc != OK) break; /* Conditions loop */
3689 /* If the result is the one for which "message" and/or "log_message" are used,
3690 handle the values of these modifiers. If there isn't a log message set, we make
3691 it the same as the user message.
3693 "message" is a user message that will be included in an SMTP response. Unless
3694 it is empty, it overrides any previously set user message.
3696 "log_message" is a non-user message, and it adds to any existing non-user
3697 message that is already set.
3699 Most verbs have but a single return for which the messages are relevant, but
3700 for "discard", it's useful to have the log message both when it succeeds and
3701 when it fails. For "accept", the message is used in the OK case if there is no
3702 "endpass", but (for backwards compatibility) in the FAIL case if "endpass" is
3705 if (*epp && rc == OK) user_message = NULL;
3707 if (((1<<rc) & msgcond[verb]) != 0)
3710 uschar *old_user_msgptr = *user_msgptr;
3711 uschar *old_log_msgptr = (*log_msgptr != NULL)? *log_msgptr : old_user_msgptr;
3713 /* If the verb is "warn", messages generated by conditions (verification or
3714 nested ACLs) are always discarded. This also happens for acceptance verbs
3715 when they actually do accept. Only messages specified at this level are used.
3716 However, the value of an existing message is available in $acl_verify_message
3717 during expansions. */
3719 if (verb == ACL_WARN ||
3720 (rc == OK && (verb == ACL_ACCEPT || verb == ACL_DISCARD)))
3721 *log_msgptr = *user_msgptr = NULL;
3723 if (user_message != NULL)
3725 acl_verify_message = old_user_msgptr;
3726 expmessage = expand_string(user_message);
3727 if (expmessage == NULL)
3729 if (!expand_string_forcedfail)
3730 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
3731 user_message, expand_string_message);
3733 else if (expmessage[0] != 0) *user_msgptr = expmessage;
3736 if (log_message != NULL)
3738 acl_verify_message = old_log_msgptr;
3739 expmessage = expand_string(log_message);
3740 if (expmessage == NULL)
3742 if (!expand_string_forcedfail)
3743 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
3744 log_message, expand_string_message);
3746 else if (expmessage[0] != 0)
3748 *log_msgptr = (*log_msgptr == NULL)? expmessage :
3749 string_sprintf("%s: %s", expmessage, *log_msgptr);
3753 /* If no log message, default it to the user message */
3755 if (*log_msgptr == NULL) *log_msgptr = *user_msgptr;
3758 acl_verify_message = NULL;
3766 /*************************************************
3767 * Get line from a literal ACL *
3768 *************************************************/
3770 /* This function is passed to acl_read() in order to extract individual lines
3771 of a literal ACL, which we access via static pointers. We can destroy the
3772 contents because this is called only once (the compiled ACL is remembered).
3774 This code is intended to treat the data in the same way as lines in the main
3775 Exim configuration file. That is:
3777 . Leading spaces are ignored.
3779 . A \ at the end of a line is a continuation - trailing spaces after the \
3780 are permitted (this is because I don't believe in making invisible things
3781 significant). Leading spaces on the continued part of a line are ignored.
3783 . Physical lines starting (significantly) with # are totally ignored, and
3784 may appear within a sequence of backslash-continued lines.
3786 . Blank lines are ignored, but will end a sequence of continuations.
3789 Returns: a pointer to the next line
3793 static uschar *acl_text; /* Current pointer in the text */
3794 static uschar *acl_text_end; /* Points one past the terminating '0' */
3802 /* This loop handles leading blank lines and comments. */
3806 while (isspace(*acl_text)) acl_text++; /* Leading spaces/empty lines */
3807 if (*acl_text == 0) return NULL; /* No more data */
3808 yield = acl_text; /* Potential data line */
3810 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3812 /* If we hit the end before a newline, we have the whole logical line. If
3813 it's a comment, there's no more data to be given. Otherwise, yield it. */
3815 if (*acl_text == 0) return (*yield == '#')? NULL : yield;
3817 /* After reaching a newline, end this loop if the physical line does not
3818 start with '#'. If it does, it's a comment, and the loop continues. */
3820 if (*yield != '#') break;
3823 /* This loop handles continuations. We know we have some real data, ending in
3824 newline. See if there is a continuation marker at the end (ignoring trailing
3825 white space). We know that *yield is not white space, so no need to test for
3826 cont > yield in the backwards scanning loop. */
3831 for (cont = acl_text - 1; isspace(*cont); cont--);
3833 /* If no continuation follows, we are done. Mark the end of the line and
3842 /* We have encountered a continuation. Skip over whitespace at the start of
3843 the next line, and indeed the whole of the next line or lines if they are
3848 while (*(++acl_text) == ' ' || *acl_text == '\t');
3849 if (*acl_text != '#') break;
3850 while (*(++acl_text) != 0 && *acl_text != '\n');
3853 /* We have the start of a continuation line. Move all the rest of the data
3854 to join onto the previous line, and then find its end. If the end is not a
3855 newline, we are done. Otherwise loop to look for another continuation. */
3857 memmove(cont, acl_text, acl_text_end - acl_text);
3858 acl_text_end -= acl_text - cont;
3860 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3861 if (*acl_text == 0) return yield;
3864 /* Control does not reach here */
3871 /*************************************************
3872 * Check access using an ACL *
3873 *************************************************/
3875 /* This function is called from address_check. It may recurse via
3876 acl_check_condition() - hence the use of a level to stop looping. The ACL is
3877 passed as a string which is expanded. A forced failure implies no access check
3878 is required. If the result is a single word, it is taken as the name of an ACL
3879 which is sought in the global ACL tree. Otherwise, it is taken as literal ACL
3880 text, complete with newlines, and parsed as such. In both cases, the ACL check
3881 is then run. This function uses an auxiliary function for acl_read() to call
3882 for reading individual lines of a literal ACL. This is acl_getline(), which
3883 appears immediately above.
3886 where where called from
3887 addr address item when called from RCPT; otherwise NULL
3888 s the input string; NULL is the same as an empty ACL => DENY
3889 level the nesting level
3890 user_msgptr where to put a user error (for SMTP response)
3891 log_msgptr where to put a logging message (not for SMTP response)
3893 Returns: OK access is granted
3894 DISCARD access is apparently granted...
3895 FAIL access is denied
3896 FAIL_DROP access is denied; drop the connection
3897 DEFER can't tell at the moment
3902 acl_check_internal(int where, address_item *addr, uschar *s, int level,
3903 uschar **user_msgptr, uschar **log_msgptr)
3906 acl_block *acl = NULL;
3907 uschar *acl_name = US"inline ACL";
3910 /* Catch configuration loops */
3914 *log_msgptr = US"ACL nested too deep: possible loop";
3920 HDEBUG(D_acl) debug_printf("ACL is NULL: implicit DENY\n");
3924 /* At top level, we expand the incoming string. At lower levels, it has already
3925 been expanded as part of condition processing. */
3929 ss = expand_string(s);
3932 if (expand_string_forcedfail) return OK;
3933 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s", s,
3934 expand_string_message);
3940 while (isspace(*ss))ss++;
3942 /* If we can't find a named ACL, the default is to parse it as an inline one.
3943 (Unless it begins with a slash; non-existent files give rise to an error.) */
3947 /* Handle the case of a string that does not contain any spaces. Look for a
3948 named ACL among those read from the configuration, or a previously read file.
3949 It is possible that the pointer to the ACL is NULL if the configuration
3950 contains a name with no data. If not found, and the text begins with '/',
3951 read an ACL from a file, and save it so it can be re-used. */
3953 if (Ustrchr(ss, ' ') == NULL)
3955 tree_node *t = tree_search(acl_anchor, ss);
3958 acl = (acl_block *)(t->data.ptr);
3961 HDEBUG(D_acl) debug_printf("ACL \"%s\" is empty: implicit DENY\n", ss);
3964 acl_name = string_sprintf("ACL \"%s\"", ss);
3965 HDEBUG(D_acl) debug_printf("using ACL \"%s\"\n", ss);
3968 else if (*ss == '/')
3970 struct stat statbuf;
3971 fd = Uopen(ss, O_RDONLY, 0);
3974 *log_msgptr = string_sprintf("failed to open ACL file \"%s\": %s", ss,
3979 if (fstat(fd, &statbuf) != 0)
3981 *log_msgptr = string_sprintf("failed to fstat ACL file \"%s\": %s", ss,
3986 acl_text = store_get(statbuf.st_size + 1);
3987 acl_text_end = acl_text + statbuf.st_size + 1;
3989 if (read(fd, acl_text, statbuf.st_size) != statbuf.st_size)
3991 *log_msgptr = string_sprintf("failed to read ACL file \"%s\": %s",
3992 ss, strerror(errno));
3995 acl_text[statbuf.st_size] = 0;
3998 acl_name = string_sprintf("ACL \"%s\"", ss);
3999 HDEBUG(D_acl) debug_printf("read ACL from file %s\n", ss);
4003 /* Parse an ACL that is still in text form. If it came from a file, remember it
4004 in the ACL tree, having read it into the POOL_PERM store pool so that it
4005 persists between multiple messages. */
4009 int old_pool = store_pool;
4010 if (fd >= 0) store_pool = POOL_PERM;
4011 acl = acl_read(acl_getline, log_msgptr);
4012 store_pool = old_pool;
4013 if (acl == NULL && *log_msgptr != NULL) return ERROR;
4016 tree_node *t = store_get_perm(sizeof(tree_node) + Ustrlen(ss));
4017 Ustrcpy(t->name, ss);
4019 (void)tree_insertnode(&acl_anchor, t);
4023 /* Now we have an ACL to use. It's possible it may be NULL. */
4028 int basic_errno = 0;
4029 BOOL endpass_seen = FALSE;
4031 *log_msgptr = *user_msgptr = NULL;
4032 acl_temp_details = FALSE;
4034 if ((where == ACL_WHERE_QUIT || where == ACL_WHERE_NOTQUIT) &&
4035 acl->verb != ACL_ACCEPT &&
4036 acl->verb != ACL_WARN)
4038 *log_msgptr = string_sprintf("\"%s\" is not allowed in a QUIT or not-QUIT ACL",
4043 HDEBUG(D_acl) debug_printf("processing \"%s\"\n", verbs[acl->verb]);
4045 /* Clear out any search error message from a previous check before testing
4048 search_error_message = NULL;
4049 cond = acl_check_condition(acl->verb, acl->condition, where, addr, level,
4050 &endpass_seen, user_msgptr, log_msgptr, &basic_errno);
4052 /* Handle special returns: DEFER causes a return except on a WARN verb;
4053 ERROR always causes a return. */
4058 HDEBUG(D_acl) debug_printf("%s: condition test deferred in %s\n", verbs[acl->verb], acl_name);
4059 if (basic_errno != ERRNO_CALLOUTDEFER)
4061 if (search_error_message != NULL && *search_error_message != 0)
4062 *log_msgptr = search_error_message;
4063 if (smtp_return_error_details) acl_temp_details = TRUE;
4067 acl_temp_details = TRUE;
4069 if (acl->verb != ACL_WARN) return DEFER;
4072 default: /* Paranoia */
4074 HDEBUG(D_acl) debug_printf("%s: condition test error in %s\n", verbs[acl->verb], acl_name);
4078 HDEBUG(D_acl) debug_printf("%s: condition test succeeded in %s\n",
4079 verbs[acl->verb], acl_name);
4083 HDEBUG(D_acl) debug_printf("%s: condition test failed in %s\n", verbs[acl->verb], acl_name);
4086 /* DISCARD and DROP can happen only from a nested ACL condition, and
4087 DISCARD can happen only for an "accept" or "discard" verb. */
4090 HDEBUG(D_acl) debug_printf("%s: condition test yielded \"discard\" in %s\n",
4091 verbs[acl->verb], acl_name);
4095 HDEBUG(D_acl) debug_printf("%s: condition test yielded \"drop\" in %s\n",
4096 verbs[acl->verb], acl_name);
4100 /* At this point, cond for most verbs is either OK or FAIL or (as a result of
4101 a nested ACL condition) FAIL_DROP. However, for WARN, cond may be DEFER, and
4102 for ACCEPT and DISCARD, it may be DISCARD after a nested ACL call. */
4107 if (cond == OK || cond == DISCARD) return cond;
4110 HDEBUG(D_acl) debug_printf("accept: endpass encountered - denying access\n");
4118 acl_temp_details = TRUE;
4124 if (cond == OK) return FAIL;
4128 if (cond == OK || cond == DISCARD) return DISCARD;
4131 HDEBUG(D_acl) debug_printf("discard: endpass encountered - denying access\n");
4137 if (cond == OK) return FAIL_DROP;
4141 if (cond != OK) return cond;
4146 acl_warn(where, *user_msgptr, *log_msgptr);
4147 else if (cond == DEFER && (log_extra_selector & LX_acl_warn_skipped) != 0)
4148 log_write(0, LOG_MAIN, "%s Warning: ACL \"warn\" statement skipped: "
4149 "condition test deferred%s%s", host_and_ident(TRUE),
4150 (*log_msgptr == NULL)? US"" : US": ",
4151 (*log_msgptr == NULL)? US"" : *log_msgptr);
4152 *log_msgptr = *user_msgptr = NULL; /* In case implicit DENY follows */
4156 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown verb %d",
4161 /* Pass to the next ACL item */
4166 /* We have reached the end of the ACL. This is an implicit DENY. */
4168 HDEBUG(D_acl) debug_printf("end of %s: implicit DENY\n", acl_name);
4175 /* Same args as acl_check_internal() above, but the string s is
4176 the name of an ACL followed optionally by up to 9 space-separated arguments.
4177 The name and args are separately expanded. Args go into $acl_arg globals. */
4179 acl_check_wargs(int where, address_item *addr, uschar *s, int level,
4180 uschar **user_msgptr, uschar **log_msgptr)
4183 uschar * tmp_arg[9]; /* must match acl_arg[] */
4184 uschar * sav_arg[9]; /* must match acl_arg[] */
4190 if (!(tmp = string_dequote(&s)) || !(name = expand_string(tmp)))
4193 for (i = 0; i < 9; i++)
4195 while (*s && isspace(*s)) s++;
4197 if (!(tmp = string_dequote(&s)) || !(tmp_arg[i] = expand_string(tmp)))
4204 sav_narg = acl_narg;
4206 for (i = 0; i < acl_narg; i++)
4208 sav_arg[i] = acl_arg[i];
4209 acl_arg[i] = tmp_arg[i];
4213 sav_arg[i] = acl_arg[i];
4214 acl_arg[i++] = NULL;
4217 ret = acl_check_internal(where, addr, name, level, user_msgptr, log_msgptr);
4219 acl_narg = sav_narg;
4220 for (i = 0; i < 9; i++) acl_arg[i] = sav_arg[i];
4224 if (expand_string_forcedfail) return ERROR;
4225 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s",
4226 tmp, expand_string_message);
4227 return search_find_defer?DEFER:ERROR;
4232 /*************************************************
4233 * Check access using an ACL *
4234 *************************************************/
4236 /* Alternate interface for ACL, used by expansions */
4238 acl_eval(int where, uschar *s, uschar **user_msgptr, uschar **log_msgptr)
4241 address_item *addr = NULL;
4243 *user_msgptr = *log_msgptr = NULL;
4244 sender_verified_failed = NULL;
4245 ratelimiters_cmd = NULL;
4246 log_reject_target = LOG_MAIN|LOG_REJECT;
4248 if (where == ACL_WHERE_RCPT)
4250 adb = address_defaults;
4252 addr->address = expand_string(US"$local_part@$domain");
4253 addr->domain = deliver_domain;
4254 addr->local_part = deliver_localpart;
4255 addr->cc_local_part = deliver_localpart;
4256 addr->lc_local_part = deliver_localpart;
4259 return acl_check_internal(where, addr, s, 0, user_msgptr, log_msgptr);
4264 /* This is the external interface for ACL checks. It sets up an address and the
4265 expansions for $domain and $local_part when called after RCPT, then calls
4266 acl_check_internal() to do the actual work.
4269 where ACL_WHERE_xxxx indicating where called from
4270 recipient RCPT address for RCPT check, else NULL
4271 s the input string; NULL is the same as an empty ACL => DENY
4272 user_msgptr where to put a user error (for SMTP response)
4273 log_msgptr where to put a logging message (not for SMTP response)
4275 Returns: OK access is granted by an ACCEPT verb
4276 DISCARD access is granted by a DISCARD verb
4277 FAIL access is denied
4278 FAIL_DROP access is denied; drop the connection
4279 DEFER can't tell at the moment
4282 int acl_where = ACL_WHERE_UNKNOWN;
4285 acl_check(int where, uschar *recipient, uschar *s, uschar **user_msgptr,
4286 uschar **log_msgptr)
4290 address_item *addr = NULL;
4292 *user_msgptr = *log_msgptr = NULL;
4293 sender_verified_failed = NULL;
4294 ratelimiters_cmd = NULL;
4295 log_reject_target = LOG_MAIN|LOG_REJECT;
4297 #ifdef EXPERIMENTAL_PRDR
4298 if (where == ACL_WHERE_RCPT || where == ACL_WHERE_PRDR )
4300 if (where == ACL_WHERE_RCPT )
4303 adb = address_defaults;
4305 addr->address = recipient;
4306 if (deliver_split_address(addr) == DEFER)
4308 *log_msgptr = US"defer in percent_hack_domains check";
4311 deliver_domain = addr->domain;
4312 deliver_localpart = addr->local_part;
4316 rc = acl_check_internal(where, addr, s, 0, user_msgptr, log_msgptr);
4317 acl_where = ACL_WHERE_UNKNOWN;
4319 /* Cutthrough - if requested,
4320 and WHERE_RCPT and not yet opened conn as result of recipient-verify,
4321 and rcpt acl returned accept,
4322 and first recipient (cancel on any subsequents)
4323 open one now and run it up to RCPT acceptance.
4324 A failed verify should cancel cutthrough request.
4326 Initial implementation: dual-write to spool.
4327 Assume the rxd datastream is now being copied byte-for-byte to an open cutthrough connection.
4329 Cease cutthrough copy on rxd final dot; do not send one.
4331 On a data acl, if not accept and a cutthrough conn is open, hard-close it (no SMTP niceness).
4333 On data acl accept, terminate the dataphase on an open cutthrough conn. If accepted or
4334 perm-rejected, reflect that to the original sender - and dump the spooled copy.
4335 If temp-reject, close the conn (and keep the spooled copy).
4336 If conn-failure, no action (and keep the spooled copy).
4340 case ACL_WHERE_RCPT:
4341 #ifdef EXPERIMENTAL_PRDR
4342 case ACL_WHERE_PRDR:
4344 if( rcpt_count > 1 )
4345 cancel_cutthrough_connection("more than one recipient");
4346 else if (rc == OK && cutthrough_delivery && cutthrough_fd < 0)
4347 open_cutthrough_connection(addr);
4350 case ACL_WHERE_PREDATA:
4352 cutthrough_predata();
4354 cancel_cutthrough_connection("predata acl not ok");
4357 case ACL_WHERE_QUIT:
4358 case ACL_WHERE_NOTQUIT:
4359 cancel_cutthrough_connection("quit or notquit");
4366 deliver_domain = deliver_localpart = deliver_address_data =
4367 sender_address_data = NULL;
4369 /* A DISCARD response is permitted only for message ACLs, excluding the PREDATA
4370 ACL, which is really in the middle of an SMTP command. */
4374 if (where > ACL_WHERE_NOTSMTP || where == ACL_WHERE_PREDATA)
4376 log_write(0, LOG_MAIN|LOG_PANIC, "\"discard\" verb not allowed in %s "
4377 "ACL", acl_wherenames[where]);
4383 /* A DROP response is not permitted from MAILAUTH */
4385 if (rc == FAIL_DROP && where == ACL_WHERE_MAILAUTH)
4387 log_write(0, LOG_MAIN|LOG_PANIC, "\"drop\" verb not allowed in %s "
4388 "ACL", acl_wherenames[where]);
4392 /* Before giving a response, take a look at the length of any user message, and
4393 split it up into multiple lines if possible. */
4395 *user_msgptr = string_split_message(*user_msgptr);
4396 if (fake_response != OK)
4397 fake_response_text = string_split_message(fake_response_text);
4403 /*************************************************
4404 * Create ACL variable *
4405 *************************************************/
4407 /* Create an ACL variable or reuse an existing one. ACL variables are in a
4408 binary tree (see tree.c) with acl_var_c and acl_var_m as root nodes.
4411 name pointer to the variable's name, starting with c or m
4413 Returns the pointer to variable's tree node
4417 acl_var_create(uschar *name)
4419 tree_node *node, **root;
4420 root = (name[0] == 'c')? &acl_var_c : &acl_var_m;
4421 node = tree_search(*root, name);
4424 node = store_get(sizeof(tree_node) + Ustrlen(name));
4425 Ustrcpy(node->name, name);
4426 (void)tree_insertnode(root, node);
4428 node->data.ptr = NULL;
4434 /*************************************************
4435 * Write an ACL variable in spool format *
4436 *************************************************/
4438 /* This function is used as a callback for tree_walk when writing variables to
4439 the spool file. To retain spool file compatibility, what is written is -aclc or
4440 -aclm followed by the rest of the name and the data length, space separated,
4441 then the value itself, starting on a new line, and terminated by an additional
4442 newline. When we had only numbered ACL variables, the first line might look
4443 like this: "-aclc 5 20". Now it might be "-aclc foo 20" for the variable called
4447 name of the variable
4448 value of the variable
4449 ctx FILE pointer (as a void pointer)
4455 acl_var_write(uschar *name, uschar *value, void *ctx)
4457 FILE *f = (FILE *)ctx;
4458 fprintf(f, "-acl%c %s %d\n%s\n", name[0], name+1, Ustrlen(value), value);