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
112 /* ACL conditions/modifiers: "delay", "control", "continue", "endpass",
113 "message", "log_message", "log_reject_target", "logwrite", and "set" are
114 modifiers that look like conditions but always return TRUE. They are used for
115 their side effects. */
117 static uschar *conditions[] = {
121 #ifdef EXPERIMENTAL_BRIGHTMAIL
127 #ifdef EXPERIMENTAL_DCC
130 #ifdef WITH_CONTENT_SCAN
134 #ifdef WITH_OLD_DEMIME
141 #ifdef EXPERIMENTAL_DMARC
151 US"log_reject_target",
153 #ifdef WITH_CONTENT_SCAN
157 #ifdef WITH_CONTENT_SCAN
162 #ifdef WITH_CONTENT_SCAN
166 US"sender_domains", US"senders", US"set",
167 #ifdef WITH_CONTENT_SCAN
170 #ifdef EXPERIMENTAL_SPF
177 /* Return values from decode_control(); keep in step with the table of names
181 CONTROL_AUTH_UNADVERTISED,
182 #ifdef EXPERIMENTAL_BRIGHTMAIL
189 #ifdef EXPERIMENTAL_DMARC
190 CONTROL_DMARC_VERIFY,
191 CONTROL_DMARC_FORENSIC,
195 CONTROL_CASEFUL_LOCAL_PART,
196 CONTROL_CASELOWER_LOCAL_PART,
197 CONTROL_CUTTHROUGH_DELIVERY,
198 CONTROL_ENFORCE_SYNC,
199 CONTROL_NO_ENFORCE_SYNC,
203 CONTROL_SUPPRESS_LOCAL_FIXUPS,
204 #ifdef WITH_CONTENT_SCAN
205 CONTROL_NO_MBOX_UNSPOOL,
209 CONTROL_NO_MULTILINE,
210 CONTROL_NO_PIPELINING,
211 CONTROL_NO_DELAY_FLUSH,
212 CONTROL_NO_CALLOUT_FLUSH
215 /* ACL control names; keep in step with the table above! This list is used for
216 turning ids into names. The actual list of recognized names is in the variable
217 control_def controls_list[] below. The fact that there are two lists is a mess
218 and should be tidied up. */
220 static uschar *controls[] = {
221 US"allow_auth_unadvertised",
222 #ifdef EXPERIMENTAL_BRIGHTMAIL
227 US"dkim_disable_verify",
229 #ifdef EXPERIMENTAL_DMARC
230 US"dmarc_disable_verify",
231 US"dmarc_enable_forensic",
235 US"caseful_local_part",
236 US"caselower_local_part",
237 US"cutthrough_delivery",
243 US"suppress_local_fixups",
244 #ifdef WITH_CONTENT_SCAN
249 US"no_multiline_responses",
255 /* Flags to indicate for which conditions/modifiers a string expansion is done
256 at the outer level. In the other cases, expansion already occurs in the
257 checking functions. */
259 static uschar cond_expand_at_top[] = {
261 TRUE, /* add_header */
262 FALSE, /* authenticated */
263 #ifdef EXPERIMENTAL_BRIGHTMAIL
264 TRUE, /* bmi_optin */
266 TRUE, /* condition */
269 #ifdef EXPERIMENTAL_DCC
272 #ifdef WITH_CONTENT_SCAN
276 #ifdef WITH_OLD_DEMIME
280 TRUE, /* dkim_signers */
281 TRUE, /* dkim_status */
283 #ifdef EXPERIMENTAL_DMARC
284 TRUE, /* dmarc_status */
288 FALSE, /* encrypted */
291 FALSE, /* local_parts */
292 TRUE, /* log_message */
293 TRUE, /* log_reject_target */
295 #ifdef WITH_CONTENT_SCAN
299 #ifdef WITH_CONTENT_SCAN
300 TRUE, /* mime_regex */
302 TRUE, /* ratelimit */
303 FALSE, /* recipients */
304 #ifdef WITH_CONTENT_SCAN
307 TRUE, /* remove_header */
308 FALSE, /* sender_domains */
311 #ifdef WITH_CONTENT_SCAN
314 #ifdef EXPERIMENTAL_SPF
316 TRUE, /* spf_guess */
321 /* Flags to identify the modifiers */
323 static uschar cond_modifiers[] = {
325 TRUE, /* add_header */
326 FALSE, /* authenticated */
327 #ifdef EXPERIMENTAL_BRIGHTMAIL
328 TRUE, /* bmi_optin */
330 FALSE, /* condition */
333 #ifdef EXPERIMENTAL_DCC
336 #ifdef WITH_CONTENT_SCAN
340 #ifdef WITH_OLD_DEMIME
344 FALSE, /* dkim_signers */
345 FALSE, /* dkim_status */
347 #ifdef EXPERIMENTAL_DMARC
348 FALSE, /* dmarc_status */
350 FALSE, /* dnslists */
352 FALSE, /* encrypted */
355 FALSE, /* local_parts */
356 TRUE, /* log_message */
357 TRUE, /* log_reject_target */
359 #ifdef WITH_CONTENT_SCAN
363 #ifdef WITH_CONTENT_SCAN
364 FALSE, /* mime_regex */
366 FALSE, /* ratelimit */
367 FALSE, /* recipients */
368 #ifdef WITH_CONTENT_SCAN
371 TRUE, /* remove_header */
372 FALSE, /* sender_domains */
375 #ifdef WITH_CONTENT_SCAN
378 #ifdef EXPERIMENTAL_SPF
380 FALSE, /* spf_guess */
385 /* Bit map vector of which conditions and modifiers are not allowed at certain
386 times. For each condition and modifier, there's a bitmap of dis-allowed times.
387 For some, it is easier to specify the negation of a small number of allowed
390 static unsigned int cond_forbids[] = {
394 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* add_header */
395 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
396 #ifdef EXPERIMENTAL_PRDR
399 (1<<ACL_WHERE_MIME)|(1<<ACL_WHERE_NOTSMTP)|
401 (1<<ACL_WHERE_NOTSMTP_START)),
403 (1<<ACL_WHERE_NOTSMTP)| /* authenticated */
404 (1<<ACL_WHERE_NOTSMTP_START)|
405 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO),
407 #ifdef EXPERIMENTAL_BRIGHTMAIL
408 (1<<ACL_WHERE_AUTH)| /* bmi_optin */
409 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
410 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_MIME)|
411 #ifdef EXPERIMENTAL_PRDR
414 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
415 (1<<ACL_WHERE_MAILAUTH)|
416 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
417 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_PREDATA)|
418 (1<<ACL_WHERE_NOTSMTP_START),
425 /* Certain types of control are always allowed, so we let it through
426 always and check in the control processing itself. */
430 #ifdef EXPERIMENTAL_DCC
432 ~((1<<ACL_WHERE_DATA)| /* dcc */
433 #ifdef EXPERIMENTAL_PRDR
435 #endif /* EXPERIMENTAL_PRDR */
436 (1<<ACL_WHERE_NOTSMTP)),
439 #ifdef WITH_CONTENT_SCAN
441 ~(1<<ACL_WHERE_MIME), /* decode */
444 (1<<ACL_WHERE_NOTQUIT), /* delay */
446 #ifdef WITH_OLD_DEMIME
448 ~((1<<ACL_WHERE_DATA)| /* demime */
449 #ifdef EXPERIMENTAL_PRDR
451 #endif /* EXPERIMENTAL_PRDR */
452 (1<<ACL_WHERE_NOTSMTP)),
457 ~(1<<ACL_WHERE_DKIM), /* dkim_signers */
460 ~(1<<ACL_WHERE_DKIM), /* dkim_status */
463 #ifdef EXPERIMENTAL_DMARC
465 ~(1<<ACL_WHERE_DATA), /* dmarc_status */
468 (1<<ACL_WHERE_NOTSMTP)| /* dnslists */
469 (1<<ACL_WHERE_NOTSMTP_START),
472 ~((1<<ACL_WHERE_RCPT) /* domains */
473 #ifdef EXPERIMENTAL_PRDR
478 (1<<ACL_WHERE_NOTSMTP)| /* encrypted */
479 (1<<ACL_WHERE_CONNECT)|
480 (1<<ACL_WHERE_NOTSMTP_START)|
485 (1<<ACL_WHERE_NOTSMTP)| /* hosts */
486 (1<<ACL_WHERE_NOTSMTP_START),
489 ~((1<<ACL_WHERE_RCPT) /* local_parts */
490 #ifdef EXPERIMENTAL_PRDR
497 0, /* log_reject_target */
501 #ifdef WITH_CONTENT_SCAN
503 ~((1<<ACL_WHERE_DATA)| /* malware */
504 #ifdef EXPERIMENTAL_PRDR
506 #endif /* EXPERIMENTAL_PRDR */
507 (1<<ACL_WHERE_NOTSMTP)),
512 #ifdef WITH_CONTENT_SCAN
514 ~(1<<ACL_WHERE_MIME), /* mime_regex */
520 ~(1<<ACL_WHERE_RCPT), /* recipients */
522 #ifdef WITH_CONTENT_SCAN
524 ~((1<<ACL_WHERE_DATA)| /* regex */
525 #ifdef EXPERIMENTAL_PRDR
527 #endif /* EXPERIMENTAL_PRDR */
528 (1<<ACL_WHERE_NOTSMTP)|
529 (1<<ACL_WHERE_MIME)),
533 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* remove_header */
534 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
535 #ifdef EXPERIMENTAL_PRDR
538 (1<<ACL_WHERE_MIME)|(1<<ACL_WHERE_NOTSMTP)|
539 (1<<ACL_WHERE_NOTSMTP_START)),
541 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* sender_domains */
543 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
544 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
545 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
547 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* senders */
549 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
550 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
551 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
555 #ifdef WITH_CONTENT_SCAN
557 ~((1<<ACL_WHERE_DATA)| /* spam */
558 #ifdef EXPERIMENTAL_PRDR
560 #endif /* EXPERIMENTAL_PRDR */
561 (1<<ACL_WHERE_NOTSMTP)),
564 #ifdef EXPERIMENTAL_SPF
565 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* spf */
567 (1<<ACL_WHERE_MAILAUTH)|
568 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
569 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY)|
570 (1<<ACL_WHERE_NOTSMTP)|
571 (1<<ACL_WHERE_NOTSMTP_START),
573 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* spf_guess */
575 (1<<ACL_WHERE_MAILAUTH)|
576 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
577 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY)|
578 (1<<ACL_WHERE_NOTSMTP)|
579 (1<<ACL_WHERE_NOTSMTP_START),
582 /* Certain types of verify are always allowed, so we let it through
583 always and check in the verify function itself */
589 /* Bit map vector of which controls are not allowed at certain times. For
590 each control, there's a bitmap of dis-allowed times. For some, it is easier to
591 specify the negation of a small number of allowed times. */
593 static unsigned int control_forbids[] = {
595 ~((1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)), /* allow_auth_unadvertised */
597 #ifdef EXPERIMENTAL_BRIGHTMAIL
604 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* dkim_disable_verify */
605 #ifdef EXPERIMENTAL_PRDR
607 #endif /* EXPERIMENTAL_PRDR */
608 (1<<ACL_WHERE_NOTSMTP_START),
611 #ifdef EXPERIMENTAL_DMARC
612 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* dmarc_disable_verify */
613 (1<<ACL_WHERE_NOTSMTP_START),
614 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* dmarc_enable_forensic */
615 (1<<ACL_WHERE_NOTSMTP_START),
618 (1<<ACL_WHERE_NOTSMTP)|
619 (1<<ACL_WHERE_NOTSMTP_START)|
620 (1<<ACL_WHERE_NOTQUIT), /* dscp */
625 ~(1<<ACL_WHERE_RCPT), /* caseful_local_part */
628 ~(1<<ACL_WHERE_RCPT), /* caselower_local_part */
631 0, /* cutthrough_delivery */
633 (1<<ACL_WHERE_NOTSMTP)| /* enforce_sync */
634 (1<<ACL_WHERE_NOTSMTP_START),
636 (1<<ACL_WHERE_NOTSMTP)| /* no_enforce_sync */
637 (1<<ACL_WHERE_NOTSMTP_START),
640 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* freeze */
641 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
642 // (1<<ACL_WHERE_PRDR)| /* Not allow one user to freeze for all */
643 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)),
646 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* queue_only */
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)| /* submission */
653 (1<<ACL_WHERE_PREDATA)),
656 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* suppress_local_fixups */
657 (1<<ACL_WHERE_PREDATA)|
658 (1<<ACL_WHERE_NOTSMTP_START)),
660 #ifdef WITH_CONTENT_SCAN
662 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* no_mbox_unspool */
663 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
664 // (1<<ACL_WHERE_PRDR)| /* Not allow one user to freeze for all */
665 (1<<ACL_WHERE_MIME)),
669 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakedefer */
670 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
671 #ifdef EXPERIMENTAL_PRDR
673 #endif /* EXPERIMENTAL_PRDR */
674 (1<<ACL_WHERE_MIME)),
677 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakereject */
678 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
679 #ifdef EXPERIMENTAL_PRDR
681 #endif /* EXPERIMENTAL_PRDR */
682 (1<<ACL_WHERE_MIME)),
684 (1<<ACL_WHERE_NOTSMTP)| /* no_multiline */
685 (1<<ACL_WHERE_NOTSMTP_START),
687 (1<<ACL_WHERE_NOTSMTP)| /* no_pipelining */
688 (1<<ACL_WHERE_NOTSMTP_START),
690 (1<<ACL_WHERE_NOTSMTP)| /* no_delay_flush */
691 (1<<ACL_WHERE_NOTSMTP_START),
693 (1<<ACL_WHERE_NOTSMTP)| /* no_callout_flush */
694 (1<<ACL_WHERE_NOTSMTP_START)
697 /* Structure listing various control arguments, with their characteristics. */
699 typedef struct control_def {
701 int value; /* CONTROL_xxx value */
702 BOOL has_option; /* Has /option(s) following */
705 static control_def controls_list[] = {
706 { US"allow_auth_unadvertised", CONTROL_AUTH_UNADVERTISED, FALSE },
707 #ifdef EXPERIMENTAL_BRIGHTMAIL
708 { US"bmi_run", CONTROL_BMI_RUN, FALSE },
710 { US"debug", CONTROL_DEBUG, TRUE },
712 { US"dkim_disable_verify", CONTROL_DKIM_VERIFY, FALSE },
714 #ifdef EXPERIMENTAL_DMARC
715 { US"dmarc_disable_verify", CONTROL_DMARC_VERIFY, FALSE },
716 { US"dmarc_enable_forensic", CONTROL_DMARC_FORENSIC, FALSE },
718 { US"dscp", CONTROL_DSCP, TRUE },
719 { US"caseful_local_part", CONTROL_CASEFUL_LOCAL_PART, FALSE },
720 { US"caselower_local_part", CONTROL_CASELOWER_LOCAL_PART, FALSE },
721 { US"enforce_sync", CONTROL_ENFORCE_SYNC, FALSE },
722 { US"freeze", CONTROL_FREEZE, TRUE },
723 { US"no_callout_flush", CONTROL_NO_CALLOUT_FLUSH, FALSE },
724 { US"no_delay_flush", CONTROL_NO_DELAY_FLUSH, FALSE },
725 { US"no_enforce_sync", CONTROL_NO_ENFORCE_SYNC, FALSE },
726 { US"no_multiline_responses", CONTROL_NO_MULTILINE, FALSE },
727 { US"no_pipelining", CONTROL_NO_PIPELINING, FALSE },
728 { US"queue_only", CONTROL_QUEUE_ONLY, FALSE },
729 #ifdef WITH_CONTENT_SCAN
730 { US"no_mbox_unspool", CONTROL_NO_MBOX_UNSPOOL, FALSE },
732 { US"fakedefer", CONTROL_FAKEDEFER, TRUE },
733 { US"fakereject", CONTROL_FAKEREJECT, TRUE },
734 { US"submission", CONTROL_SUBMISSION, TRUE },
735 { US"suppress_local_fixups", CONTROL_SUPPRESS_LOCAL_FIXUPS, FALSE },
736 { US"cutthrough_delivery", CONTROL_CUTTHROUGH_DELIVERY, FALSE }
739 /* Support data structures for Client SMTP Authorization. acl_verify_csa()
740 caches its result in a tree to avoid repeated DNS queries. The result is an
741 integer code which is used as an index into the following tables of
742 explanatory strings and verification return codes. */
744 static tree_node *csa_cache = NULL;
746 enum { CSA_UNKNOWN, CSA_OK, CSA_DEFER_SRV, CSA_DEFER_ADDR,
747 CSA_FAIL_EXPLICIT, CSA_FAIL_DOMAIN, CSA_FAIL_NOADDR, CSA_FAIL_MISMATCH };
749 /* The acl_verify_csa() return code is translated into an acl_verify() return
750 code using the following table. It is OK unless the client is definitely not
751 authorized. This is because CSA is supposed to be optional for sending sites,
752 so recipients should not be too strict about checking it - especially because
753 DNS problems are quite likely to occur. It's possible to use $csa_status in
754 further ACL conditions to distinguish ok, unknown, and defer if required, but
755 the aim is to make the usual configuration simple. */
757 static int csa_return_code[] = {
759 FAIL, FAIL, FAIL, FAIL
762 static uschar *csa_status_string[] = {
763 US"unknown", US"ok", US"defer", US"defer",
764 US"fail", US"fail", US"fail", US"fail"
767 static uschar *csa_reason_string[] = {
770 US"deferred (SRV lookup failed)",
771 US"deferred (target address lookup failed)",
772 US"failed (explicit authorization required)",
773 US"failed (host name not authorized)",
774 US"failed (no authorized addresses)",
775 US"failed (client address mismatch)"
778 /* Options for the ratelimit condition. Note that there are two variants of
779 the per_rcpt option, depending on the ACL that is used to measure the rate.
780 However any ACL must be able to look up per_rcpt rates in /noupdate mode,
781 so the two variants must have the same internal representation as well as
782 the same configuration string. */
785 RATE_PER_WHAT, RATE_PER_CLASH, RATE_PER_ADDR, RATE_PER_BYTE, RATE_PER_CMD,
786 RATE_PER_CONN, RATE_PER_MAIL, RATE_PER_RCPT, RATE_PER_ALLRCPTS
789 #define RATE_SET(var,new) \
790 (((var) == RATE_PER_WHAT) ? ((var) = RATE_##new) : ((var) = RATE_PER_CLASH))
792 static uschar *ratelimit_option_string[] = {
793 US"?", US"!", US"per_addr", US"per_byte", US"per_cmd",
794 US"per_conn", US"per_mail", US"per_rcpt", US"per_rcpt"
797 /* Enable recursion between acl_check_internal() and acl_check_condition() */
799 static int acl_check_wargs(int, address_item *, uschar *, int, uschar **,
803 /*************************************************
804 * Pick out name from list *
805 *************************************************/
807 /* Use a binary chop method
814 Returns: offset in list, or -1 if not found
818 acl_checkname(uschar *name, uschar **list, int end)
824 int mid = (start + end)/2;
825 int c = Ustrcmp(name, list[mid]);
826 if (c == 0) return mid;
827 if (c < 0) end = mid; else start = mid + 1;
834 /*************************************************
835 * Read and parse one ACL *
836 *************************************************/
838 /* This function is called both from readconf in order to parse the ACLs in the
839 configuration file, and also when an ACL is encountered dynamically (e.g. as
840 the result of an expansion). It is given a function to call in order to
841 retrieve the lines of the ACL. This function handles skipping comments and
842 blank lines (where relevant).
845 func function to get next line of ACL
846 error where to put an error message
848 Returns: pointer to ACL, or NULL
849 NULL can be legal (empty ACL); in this case error will be NULL
853 acl_read(uschar *(*func)(void), uschar **error)
855 acl_block *yield = NULL;
856 acl_block **lastp = &yield;
857 acl_block *this = NULL;
858 acl_condition_block *cond;
859 acl_condition_block **condp = NULL;
864 while ((s = (*func)()) != NULL)
867 BOOL negated = FALSE;
868 uschar *saveline = s;
871 /* Conditions (but not verbs) are allowed to be negated by an initial
874 while (isspace(*s)) s++;
881 /* Read the name of a verb or a condition, or the start of a new ACL, which
882 can be started by a name, or by a macro definition. */
884 s = readconf_readname(name, sizeof(name), s);
885 if (*s == ':' || (isupper(name[0]) && *s == '=')) return yield;
887 /* If a verb is unrecognized, it may be another condition or modifier that
888 continues the previous verb. */
890 v = acl_checkname(name, verbs, sizeof(verbs)/sizeof(char *));
895 *error = string_sprintf("unknown ACL verb \"%s\" in \"%s\"", name,
907 *error = string_sprintf("malformed ACL line \"%s\"", saveline);
910 this = store_get(sizeof(acl_block));
912 lastp = &(this->next);
915 this->condition = NULL;
916 condp = &(this->condition);
917 if (*s == 0) continue; /* No condition on this line */
923 s = readconf_readname(name, sizeof(name), s); /* Condition name */
926 /* Handle a condition or modifier. */
928 c = acl_checkname(name, conditions, sizeof(conditions)/sizeof(char *));
931 *error = string_sprintf("unknown ACL condition/modifier in \"%s\"",
936 /* The modifiers may not be negated */
938 if (negated && cond_modifiers[c])
940 *error = string_sprintf("ACL error: negation is not allowed with "
941 "\"%s\"", conditions[c]);
945 /* ENDPASS may occur only with ACCEPT or DISCARD. */
947 if (c == ACLC_ENDPASS &&
948 this->verb != ACL_ACCEPT &&
949 this->verb != ACL_DISCARD)
951 *error = string_sprintf("ACL error: \"%s\" is not allowed with \"%s\"",
952 conditions[c], verbs[this->verb]);
956 cond = store_get(sizeof(acl_condition_block));
959 cond->u.negated = negated;
962 condp = &(cond->next);
964 /* The "set" modifier is different in that its argument is "name=value"
965 rather than just a value, and we can check the validity of the name, which
966 gives us a variable name to insert into the data block. The original ACL
967 variable names were acl_c0 ... acl_c9 and acl_m0 ... acl_m9. This was
968 extended to 20 of each type, but after that people successfully argued for
969 arbitrary names. In the new scheme, the names must start with acl_c or acl_m.
970 After that, we allow alphanumerics and underscores, but the first character
971 after c or m must be a digit or an underscore. This retains backwards
978 if (Ustrncmp(s, "acl_c", 5) != 0 &&
979 Ustrncmp(s, "acl_m", 5) != 0)
981 *error = string_sprintf("invalid variable name after \"set\" in ACL "
982 "modifier \"set %s\" (must start \"acl_c\" or \"acl_m\")", s);
987 if (!isdigit(*endptr) && *endptr != '_')
989 *error = string_sprintf("invalid variable name after \"set\" in ACL "
990 "modifier \"set %s\" (digit or underscore must follow acl_c or acl_m)",
995 while (*endptr != 0 && *endptr != '=' && !isspace(*endptr))
997 if (!isalnum(*endptr) && *endptr != '_')
999 *error = string_sprintf("invalid character \"%c\" in variable name "
1000 "in ACL modifier \"set %s\"", *endptr, s);
1006 cond->u.varname = string_copyn(s + 4, endptr - s - 4);
1008 while (isspace(*s)) s++;
1011 /* For "set", we are now positioned for the data. For the others, only
1012 "endpass" has no data */
1014 if (c != ACLC_ENDPASS)
1018 *error = string_sprintf("\"=\" missing after ACL \"%s\" %s", name,
1019 cond_modifiers[c]? US"modifier" : US"condition");
1022 while (isspace(*s)) s++;
1023 cond->arg = string_copy(s);
1032 /*************************************************
1033 * Set up added header line(s) *
1034 *************************************************/
1036 /* This function is called by the add_header modifier, and also from acl_warn()
1037 to implement the now-deprecated way of adding header lines using "message" on a
1038 "warn" verb. The argument is treated as a sequence of header lines which are
1039 added to a chain, provided there isn't an identical one already there.
1041 Argument: string of header lines
1046 setup_header(uschar *hstring)
1049 int hlen = Ustrlen(hstring);
1051 /* Ignore any leading newlines */
1052 while (*hstring == '\n') hstring++, hlen--;
1054 /* An empty string does nothing; ensure exactly one final newline. */
1055 if (hlen <= 0) return;
1056 if (hstring[--hlen] != '\n') hstring = string_sprintf("%s\n", hstring);
1057 else while(hstring[--hlen] == '\n') hstring[hlen+1] = '\0';
1059 /* Loop for multiple header lines, taking care about continuations */
1061 for (p = q = hstring; *p != 0; )
1064 int newtype = htype_add_bot;
1065 header_line **hptr = &acl_added_headers;
1067 /* Find next header line within the string */
1071 q = Ustrchr(q, '\n');
1072 if (*(++q) != ' ' && *q != '\t') break;
1075 /* If the line starts with a colon, interpret the instruction for where to
1076 add it. This temporarily sets up a new type. */
1080 if (strncmpic(p, US":after_received:", 16) == 0)
1082 newtype = htype_add_rec;
1085 else if (strncmpic(p, US":at_start_rfc:", 14) == 0)
1087 newtype = htype_add_rfc;
1090 else if (strncmpic(p, US":at_start:", 10) == 0)
1092 newtype = htype_add_top;
1095 else if (strncmpic(p, US":at_end:", 8) == 0)
1097 newtype = htype_add_bot;
1100 while (*p == ' ' || *p == '\t') p++;
1103 /* See if this line starts with a header name, and if not, add X-ACL-Warn:
1104 to the front of it. */
1106 for (s = p; s < q - 1; s++)
1108 if (*s == ':' || !isgraph(*s)) break;
1111 s = string_sprintf("%s%.*s", (*s == ':')? "" : "X-ACL-Warn: ", (int) (q - p), p);
1114 /* See if this line has already been added */
1116 while (*hptr != NULL)
1118 if (Ustrncmp((*hptr)->text, s, hlen) == 0) break;
1119 hptr = &((*hptr)->next);
1122 /* Add if not previously present */
1126 header_line *h = store_get(sizeof(header_line));
1135 /* Advance for next header line within the string */
1143 /*************************************************
1144 * List the added header lines *
1145 *************************************************/
1149 uschar * ret = NULL;
1150 header_line * h = acl_added_headers;
1156 if (!h) return NULL;
1161 while ((cp = Ustrchr(s, '\n')) != NULL)
1163 if (cp[1] == '\0') break;
1165 /* contains embedded newline; needs doubling */
1166 ret = string_cat(ret, &size, &ptr, s, cp-s+1);
1167 ret = string_cat(ret, &size, &ptr, US"\n", 1);
1170 /* last bit of header */
1172 ret = string_cat(ret, &size, &ptr, s, cp-s+1); /* newline-sep list */
1174 while((h = h->next));
1176 ret[ptr-1] = '\0'; /* overwrite last newline */
1181 /*************************************************
1182 * Set up removed header line(s) *
1183 *************************************************/
1185 /* This function is called by the remove_header modifier. The argument is
1186 treated as a sequence of header names which are added to a colon separated
1187 list, provided there isn't an identical one already there.
1189 Argument: string of header names
1194 setup_remove_header(uschar *hnames)
1198 if (acl_removed_headers == NULL)
1199 acl_removed_headers = hnames;
1201 acl_removed_headers = string_sprintf("%s : %s", acl_removed_headers, hnames);
1207 /*************************************************
1209 *************************************************/
1211 /* This function is called when a WARN verb's conditions are true. It adds to
1212 the message's headers, and/or writes information to the log. In each case, this
1213 only happens once (per message for headers, per connection for log).
1215 ** NOTE: The header adding action using the "message" setting is historic, and
1216 its use is now deprecated. The new add_header modifier should be used instead.
1219 where ACL_WHERE_xxxx indicating which ACL this is
1220 user_message message for adding to headers
1221 log_message message for logging, if different
1227 acl_warn(int where, uschar *user_message, uschar *log_message)
1229 if (log_message != NULL && log_message != user_message)
1232 string_item *logged;
1234 text = string_sprintf("%s Warning: %s", host_and_ident(TRUE),
1235 string_printing(log_message));
1237 /* If a sender verification has failed, and the log message is "sender verify
1238 failed", add the failure message. */
1240 if (sender_verified_failed != NULL &&
1241 sender_verified_failed->message != NULL &&
1242 strcmpic(log_message, US"sender verify failed") == 0)
1243 text = string_sprintf("%s: %s", text, sender_verified_failed->message);
1245 /* Search previously logged warnings. They are kept in malloc
1246 store so they can be freed at the start of a new message. */
1248 for (logged = acl_warn_logged; logged != NULL; logged = logged->next)
1249 if (Ustrcmp(logged->text, text) == 0) break;
1253 int length = Ustrlen(text) + 1;
1254 log_write(0, LOG_MAIN, "%s", text);
1255 logged = store_malloc(sizeof(string_item) + length);
1256 logged->text = (uschar *)logged + sizeof(string_item);
1257 memcpy(logged->text, text, length);
1258 logged->next = acl_warn_logged;
1259 acl_warn_logged = logged;
1263 /* If there's no user message, we are done. */
1265 if (user_message == NULL) return;
1267 /* If this isn't a message ACL, we can't do anything with a user message.
1270 if (where > ACL_WHERE_NOTSMTP)
1272 log_write(0, LOG_MAIN|LOG_PANIC, "ACL \"warn\" with \"message\" setting "
1273 "found in a non-message (%s) ACL: cannot specify header lines here: "
1274 "message ignored", acl_wherenames[where]);
1278 /* The code for setting up header lines is now abstracted into a separate
1279 function so that it can be used for the add_header modifier as well. */
1281 setup_header(user_message);
1286 /*************************************************
1287 * Verify and check reverse DNS *
1288 *************************************************/
1290 /* Called from acl_verify() below. We look up the host name(s) of the client IP
1291 address if this has not yet been done. The host_name_lookup() function checks
1292 that one of these names resolves to an address list that contains the client IP
1293 address, so we don't actually have to do the check here.
1296 user_msgptr pointer for user message
1297 log_msgptr pointer for log message
1299 Returns: OK verification condition succeeded
1300 FAIL verification failed
1301 DEFER there was a problem verifying
1305 acl_verify_reverse(uschar **user_msgptr, uschar **log_msgptr)
1309 user_msgptr = user_msgptr; /* stop compiler warning */
1311 /* Previous success */
1313 if (sender_host_name != NULL) return OK;
1315 /* Previous failure */
1317 if (host_lookup_failed)
1319 *log_msgptr = string_sprintf("host lookup failed%s", host_lookup_msg);
1323 /* Need to do a lookup */
1326 debug_printf("looking up host name to force name/address consistency check\n");
1328 if ((rc = host_name_lookup()) != OK)
1330 *log_msgptr = (rc == DEFER)?
1331 US"host lookup deferred for reverse lookup check"
1333 string_sprintf("host lookup failed for reverse lookup check%s",
1335 return rc; /* DEFER or FAIL */
1338 host_build_sender_fullhost();
1344 /*************************************************
1345 * Check client IP address matches CSA target *
1346 *************************************************/
1348 /* Called from acl_verify_csa() below. This routine scans a section of a DNS
1349 response for address records belonging to the CSA target hostname. The section
1350 is specified by the reset argument, either RESET_ADDITIONAL or RESET_ANSWERS.
1351 If one of the addresses matches the client's IP address, then the client is
1352 authorized by CSA. If there are target IP addresses but none of them match
1353 then the client is using an unauthorized IP address. If there are no target IP
1354 addresses then the client cannot be using an authorized IP address. (This is
1355 an odd configuration - why didn't the SRV record have a weight of 1 instead?)
1358 dnsa the DNS answer block
1359 dnss a DNS scan block for us to use
1360 reset option specifing what portion to scan, as described above
1361 target the target hostname to use for matching RR names
1363 Returns: CSA_OK successfully authorized
1364 CSA_FAIL_MISMATCH addresses found but none matched
1365 CSA_FAIL_NOADDR no target addresses found
1369 acl_verify_csa_address(dns_answer *dnsa, dns_scan *dnss, int reset,
1375 BOOL target_found = FALSE;
1377 for (rr = dns_next_rr(dnsa, dnss, reset);
1379 rr = dns_next_rr(dnsa, dnss, RESET_NEXT))
1381 /* Check this is an address RR for the target hostname. */
1385 && rr->type != T_AAAA
1392 if (strcmpic(target, rr->name) != 0) continue;
1394 target_found = TRUE;
1396 /* Turn the target address RR into a list of textual IP addresses and scan
1397 the list. There may be more than one if it is an A6 RR. */
1399 for (da = dns_address_from_rr(dnsa, rr); da != NULL; da = da->next)
1401 /* If the client IP address matches the target IP address, it's good! */
1403 DEBUG(D_acl) debug_printf("CSA target address is %s\n", da->address);
1405 if (strcmpic(sender_host_address, da->address) == 0) return CSA_OK;
1409 /* If we found some target addresses but none of them matched, the client is
1410 using an unauthorized IP address, otherwise the target has no authorized IP
1413 if (target_found) return CSA_FAIL_MISMATCH;
1414 else return CSA_FAIL_NOADDR;
1419 /*************************************************
1420 * Verify Client SMTP Authorization *
1421 *************************************************/
1423 /* Called from acl_verify() below. This routine calls dns_lookup_special()
1424 to find the CSA SRV record corresponding to the domain argument, or
1425 $sender_helo_name if no argument is provided. It then checks that the
1426 client is authorized, and that its IP address corresponds to the SRV
1427 target's address by calling acl_verify_csa_address() above. The address
1428 should have been returned in the DNS response's ADDITIONAL section, but if
1429 not we perform another DNS lookup to get it.
1432 domain pointer to optional parameter following verify = csa
1434 Returns: CSA_UNKNOWN no valid CSA record found
1435 CSA_OK successfully authorized
1436 CSA_FAIL_* client is definitely not authorized
1437 CSA_DEFER_* there was a DNS problem
1441 acl_verify_csa(uschar *domain)
1445 int priority, weight, port;
1452 /* Work out the domain we are using for the CSA lookup. The default is the
1453 client's HELO domain. If the client has not said HELO, use its IP address
1454 instead. If it's a local client (exim -bs), CSA isn't applicable. */
1456 while (isspace(*domain) && *domain != '\0') ++domain;
1457 if (*domain == '\0') domain = sender_helo_name;
1458 if (domain == NULL) domain = sender_host_address;
1459 if (sender_host_address == NULL) return CSA_UNKNOWN;
1461 /* If we have an address literal, strip off the framing ready for turning it
1462 into a domain. The framing consists of matched square brackets possibly
1463 containing a keyword and a colon before the actual IP address. */
1465 if (domain[0] == '[')
1467 uschar *start = Ustrchr(domain, ':');
1468 if (start == NULL) start = domain;
1469 domain = string_copyn(start + 1, Ustrlen(start) - 2);
1472 /* Turn domains that look like bare IP addresses into domains in the reverse
1473 DNS. This code also deals with address literals and $sender_host_address. It's
1474 not quite kosher to treat bare domains such as EHLO 192.0.2.57 the same as
1475 address literals, but it's probably the most friendly thing to do. This is an
1476 extension to CSA, so we allow it to be turned off for proper conformance. */
1478 if (string_is_ip_address(domain, NULL) != 0)
1480 if (!dns_csa_use_reverse) return CSA_UNKNOWN;
1481 dns_build_reverse(domain, target);
1485 /* Find out if we've already done the CSA check for this domain. If we have,
1486 return the same result again. Otherwise build a new cached result structure
1487 for this domain. The name is filled in now, and the value is filled in when
1488 we return from this function. */
1490 t = tree_search(csa_cache, domain);
1491 if (t != NULL) return t->data.val;
1493 t = store_get_perm(sizeof(tree_node) + Ustrlen(domain));
1494 Ustrcpy(t->name, domain);
1495 (void)tree_insertnode(&csa_cache, t);
1497 /* Now we are ready to do the actual DNS lookup(s). */
1500 switch (dns_special_lookup(&dnsa, domain, T_CSA, &found))
1502 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1505 return t->data.val = CSA_DEFER_SRV;
1507 /* If we found nothing, the client's authorization is unknown. */
1511 return t->data.val = CSA_UNKNOWN;
1513 /* We got something! Go on to look at the reply in more detail. */
1519 /* Scan the reply for well-formed CSA SRV records. */
1521 for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS);
1523 rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT))
1525 if (rr->type != T_SRV) continue;
1527 /* Extract the numerical SRV fields (p is incremented) */
1530 GETSHORT(priority, p);
1531 GETSHORT(weight, p);
1535 debug_printf("CSA priority=%d weight=%d port=%d\n", priority, weight, port);
1537 /* Check the CSA version number */
1539 if (priority != 1) continue;
1541 /* If the domain does not have a CSA SRV record of its own (i.e. the domain
1542 found by dns_special_lookup() is a parent of the one we asked for), we check
1543 the subdomain assertions in the port field. At the moment there's only one
1544 assertion: legitimate SMTP clients are all explicitly authorized with CSA
1545 SRV records of their own. */
1547 if (found != domain)
1550 return t->data.val = CSA_FAIL_EXPLICIT;
1552 return t->data.val = CSA_UNKNOWN;
1555 /* This CSA SRV record refers directly to our domain, so we check the value
1556 in the weight field to work out the domain's authorization. 0 and 1 are
1557 unauthorized; 3 means the client is authorized but we can't check the IP
1558 address in order to authenticate it, so we treat it as unknown; values
1559 greater than 3 are undefined. */
1561 if (weight < 2) return t->data.val = CSA_FAIL_DOMAIN;
1563 if (weight > 2) continue;
1565 /* Weight == 2, which means the domain is authorized. We must check that the
1566 client's IP address is listed as one of the SRV target addresses. Save the
1567 target hostname then break to scan the additional data for its addresses. */
1569 (void)dn_expand(dnsa.answer, dnsa.answer + dnsa.answerlen, p,
1570 (DN_EXPAND_ARG4_TYPE)target, sizeof(target));
1572 DEBUG(D_acl) debug_printf("CSA target is %s\n", target);
1577 /* If we didn't break the loop then no appropriate records were found. */
1579 if (rr == NULL) return t->data.val = CSA_UNKNOWN;
1581 /* Do not check addresses if the target is ".", in accordance with RFC 2782.
1582 A target of "." indicates there are no valid addresses, so the client cannot
1583 be authorized. (This is an odd configuration because weight=2 target=. is
1584 equivalent to weight=1, but we check for it in order to keep load off the
1585 root name servers.) Note that dn_expand() turns "." into "". */
1587 if (Ustrcmp(target, "") == 0) return t->data.val = CSA_FAIL_NOADDR;
1589 /* Scan the additional section of the CSA SRV reply for addresses belonging
1590 to the target. If the name server didn't return any additional data (e.g.
1591 because it does not fully support SRV records), we need to do another lookup
1592 to obtain the target addresses; otherwise we have a definitive result. */
1594 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ADDITIONAL, target);
1595 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1597 /* The DNS lookup type corresponds to the IP version used by the client. */
1600 if (Ustrchr(sender_host_address, ':') != NULL)
1603 #endif /* HAVE_IPV6 */
1607 #if HAVE_IPV6 && defined(SUPPORT_A6)
1611 switch (dns_lookup(&dnsa, target, type, NULL))
1613 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1616 return t->data.val = CSA_DEFER_ADDR;
1618 /* If the query succeeded, scan the addresses and return the result. */
1621 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ANSWERS, target);
1622 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1623 /* else fall through */
1625 /* If the target has no IP addresses, the client cannot have an authorized
1626 IP address. However, if the target site uses A6 records (not AAAA records)
1627 we have to do yet another lookup in order to check them. */
1632 #if HAVE_IPV6 && defined(SUPPORT_A6)
1633 if (type == T_AAAA) { type = T_A6; goto DNS_LOOKUP_AGAIN; }
1636 return t->data.val = CSA_FAIL_NOADDR;
1642 /*************************************************
1643 * Handle verification (address & other) *
1644 *************************************************/
1646 enum { VERIFY_REV_HOST_LKUP, VERIFY_CERT, VERIFY_HELO, VERIFY_CSA, VERIFY_HDR_SYNTAX,
1647 VERIFY_NOT_BLIND, VERIFY_HDR_SNDR, VERIFY_SNDR, VERIFY_RCPT
1652 unsigned where_allowed; /* bitmap */
1653 BOOL no_options; /* Never has /option(s) following */
1654 unsigned alt_opt_sep; /* >0 Non-/ option separator (custom parser) */
1656 static verify_type_t verify_type_list[] = {
1657 { US"reverse_host_lookup", VERIFY_REV_HOST_LKUP, ~0, TRUE, 0 },
1658 { US"certificate", VERIFY_CERT, ~0, TRUE, 0 },
1659 { US"helo", VERIFY_HELO, ~0, TRUE, 0 },
1660 { US"csa", VERIFY_CSA, ~0, FALSE, 0 },
1661 { US"header_syntax", VERIFY_HDR_SYNTAX, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), TRUE, 0 },
1662 { US"not_blind", VERIFY_NOT_BLIND, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), TRUE, 0 },
1663 { US"header_sender", VERIFY_HDR_SNDR, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), FALSE, 0 },
1664 { US"sender", VERIFY_SNDR, (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)
1665 |(1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP),
1667 { US"recipient", VERIFY_RCPT, (1<<ACL_WHERE_RCPT), FALSE, 0 }
1671 enum { CALLOUT_DEFER_OK, CALLOUT_NOCACHE, CALLOUT_RANDOM, CALLOUT_USE_SENDER,
1672 CALLOUT_USE_POSTMASTER, CALLOUT_POSTMASTER, CALLOUT_FULLPOSTMASTER,
1673 CALLOUT_MAILFROM, CALLOUT_POSTMASTER_MAILFROM, CALLOUT_MAXWAIT, CALLOUT_CONNECT,
1680 BOOL has_option; /* Has =option(s) following */
1681 BOOL timeval; /* Has a time value */
1683 static callout_opt_t callout_opt_list[] = {
1684 { US"defer_ok", CALLOUT_DEFER_OK, 0, FALSE, FALSE },
1685 { US"no_cache", CALLOUT_NOCACHE, vopt_callout_no_cache, FALSE, FALSE },
1686 { US"random", CALLOUT_RANDOM, vopt_callout_random, FALSE, FALSE },
1687 { US"use_sender", CALLOUT_USE_SENDER, vopt_callout_recipsender, FALSE, FALSE },
1688 { US"use_postmaster", CALLOUT_USE_POSTMASTER,vopt_callout_recippmaster, FALSE, FALSE },
1689 { US"postmaster_mailfrom",CALLOUT_POSTMASTER_MAILFROM,0, TRUE, FALSE },
1690 { US"postmaster", CALLOUT_POSTMASTER, 0, FALSE, FALSE },
1691 { US"fullpostmaster", CALLOUT_FULLPOSTMASTER,vopt_callout_fullpm, FALSE, FALSE },
1692 { US"mailfrom", CALLOUT_MAILFROM, 0, TRUE, FALSE },
1693 { US"maxwait", CALLOUT_MAXWAIT, 0, TRUE, TRUE },
1694 { US"connect", CALLOUT_CONNECT, 0, TRUE, TRUE },
1695 { NULL, CALLOUT_TIME, 0, FALSE, TRUE }
1700 /* This function implements the "verify" condition. It is called when
1701 encountered in any ACL, because some tests are almost always permitted. Some
1702 just don't make sense, and always fail (for example, an attempt to test a host
1703 lookup for a non-TCP/IP message). Others are restricted to certain ACLs.
1706 where where called from
1707 addr the recipient address that the ACL is handling, or NULL
1708 arg the argument of "verify"
1709 user_msgptr pointer for user message
1710 log_msgptr pointer for log message
1711 basic_errno where to put verify errno
1713 Returns: OK verification condition succeeded
1714 FAIL verification failed
1715 DEFER there was a problem verifying
1720 acl_verify(int where, address_item *addr, uschar *arg,
1721 uschar **user_msgptr, uschar **log_msgptr, int *basic_errno)
1725 int callout_overall = -1;
1726 int callout_connect = -1;
1727 int verify_options = 0;
1729 BOOL verify_header_sender = FALSE;
1730 BOOL defer_ok = FALSE;
1731 BOOL callout_defer_ok = FALSE;
1732 BOOL no_details = FALSE;
1733 BOOL success_on_redirect = FALSE;
1734 address_item *sender_vaddr = NULL;
1735 uschar *verify_sender_address = NULL;
1736 uschar *pm_mailfrom = NULL;
1737 uschar *se_mailfrom = NULL;
1739 /* Some of the verify items have slash-separated options; some do not. Diagnose
1740 an error if options are given for items that don't expect them.
1743 uschar *slash = Ustrchr(arg, '/');
1745 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
1748 if (ss == NULL) goto BAD_VERIFY;
1750 /* Handle name/address consistency verification in a separate function. */
1752 for (vp= verify_type_list;
1753 (char *)vp < (char *)verify_type_list + sizeof(verify_type_list);
1756 if (vp->alt_opt_sep ? strncmpic(ss, vp->name, vp->alt_opt_sep) == 0
1757 : strcmpic (ss, vp->name) == 0)
1759 if ((char *)vp >= (char *)verify_type_list + sizeof(verify_type_list))
1762 if (vp->no_options && slash != NULL)
1764 *log_msgptr = string_sprintf("unexpected '/' found in \"%s\" "
1765 "(this verify item has no options)", arg);
1768 if (!(vp->where_allowed & (1<<where)))
1770 *log_msgptr = string_sprintf("cannot verify %s in ACL for %s", vp->name, acl_wherenames[where]);
1775 case VERIFY_REV_HOST_LKUP:
1776 if (sender_host_address == NULL) return OK;
1777 return acl_verify_reverse(user_msgptr, log_msgptr);
1780 /* TLS certificate verification is done at STARTTLS time; here we just
1781 test whether it was successful or not. (This is for optional verification; for
1782 mandatory verification, the connection doesn't last this long.) */
1784 if (tls_in.certificate_verified) return OK;
1785 *user_msgptr = US"no verified certificate";
1789 /* We can test the result of optional HELO verification that might have
1790 occurred earlier. If not, we can attempt the verification now. */
1792 if (!helo_verified && !helo_verify_failed) smtp_verify_helo();
1793 return helo_verified? OK : FAIL;
1796 /* Do Client SMTP Authorization checks in a separate function, and turn the
1797 result code into user-friendly strings. */
1799 rc = acl_verify_csa(list);
1800 *log_msgptr = *user_msgptr = string_sprintf("client SMTP authorization %s",
1801 csa_reason_string[rc]);
1802 csa_status = csa_status_string[rc];
1803 DEBUG(D_acl) debug_printf("CSA result %s\n", csa_status);
1804 return csa_return_code[rc];
1806 case VERIFY_HDR_SYNTAX:
1807 /* Check that all relevant header lines have the correct syntax. If there is
1808 a syntax error, we return details of the error to the sender if configured to
1809 send out full details. (But a "message" setting on the ACL can override, as
1812 rc = verify_check_headers(log_msgptr);
1813 if (rc != OK && smtp_return_error_details && *log_msgptr != NULL)
1814 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1817 case VERIFY_NOT_BLIND:
1818 /* Check that no recipient of this message is "blind", that is, every envelope
1819 recipient must be mentioned in either To: or Cc:. */
1821 rc = verify_check_notblind();
1824 *log_msgptr = string_sprintf("bcc recipient detected");
1825 if (smtp_return_error_details)
1826 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1830 /* The remaining verification tests check recipient and sender addresses,
1831 either from the envelope or from the header. There are a number of
1832 slash-separated options that are common to all of them. */
1834 case VERIFY_HDR_SNDR:
1835 verify_header_sender = TRUE;
1839 /* In the case of a sender, this can optionally be followed by an address to use
1840 in place of the actual sender (rare special-case requirement). */
1844 verify_sender_address = sender_address;
1847 while (isspace(*s)) s++;
1848 if (*s++ != '=') goto BAD_VERIFY;
1849 while (isspace(*s)) s++;
1850 verify_sender_address = string_copy(s);
1861 /* Remaining items are optional; they apply to sender and recipient
1862 verification, including "header sender" verification. */
1864 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size))
1867 if (strcmpic(ss, US"defer_ok") == 0) defer_ok = TRUE;
1868 else if (strcmpic(ss, US"no_details") == 0) no_details = TRUE;
1869 else if (strcmpic(ss, US"success_on_redirect") == 0) success_on_redirect = TRUE;
1871 /* These two old options are left for backwards compatibility */
1873 else if (strcmpic(ss, US"callout_defer_ok") == 0)
1875 callout_defer_ok = TRUE;
1876 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1879 else if (strcmpic(ss, US"check_postmaster") == 0)
1882 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1885 /* The callout option has a number of sub-options, comma separated */
1887 else if (strncmpic(ss, US"callout", 7) == 0)
1889 callout = CALLOUT_TIMEOUT_DEFAULT;
1893 while (isspace(*ss)) ss++;
1899 while (isspace(*ss)) ss++;
1901 while ((opt = string_nextinlist(&ss, &optsep, buffer, sizeof(buffer)))
1905 double period = 1.0F;
1907 for (op= callout_opt_list; op->name; op++)
1908 if (strncmpic(opt, op->name, Ustrlen(op->name)) == 0)
1911 verify_options |= op->flag;
1914 opt += Ustrlen(op->name);
1915 while (isspace(*opt)) opt++;
1918 *log_msgptr = string_sprintf("'=' expected after "
1919 "\"%s\" in ACL verify condition \"%s\"", op->name, arg);
1922 while (isspace(*opt)) opt++;
1926 period = readconf_readtime(opt, 0, FALSE);
1929 *log_msgptr = string_sprintf("bad time value in ACL condition "
1930 "\"verify %s\"", arg);
1937 case CALLOUT_DEFER_OK: callout_defer_ok = TRUE; break;
1938 case CALLOUT_POSTMASTER: pm_mailfrom = US""; break;
1939 case CALLOUT_FULLPOSTMASTER: pm_mailfrom = US""; break;
1940 case CALLOUT_MAILFROM:
1941 if (!verify_header_sender)
1943 *log_msgptr = string_sprintf("\"mailfrom\" is allowed as a "
1944 "callout option only for verify=header_sender (detected in ACL "
1945 "condition \"%s\")", arg);
1948 se_mailfrom = string_copy(opt);
1950 case CALLOUT_POSTMASTER_MAILFROM: pm_mailfrom = string_copy(opt); break;
1951 case CALLOUT_MAXWAIT: callout_overall = period; break;
1952 case CALLOUT_CONNECT: callout_connect = period; break;
1953 case CALLOUT_TIME: callout = period; break;
1959 *log_msgptr = string_sprintf("'=' expected after \"callout\" in "
1960 "ACL condition \"%s\"", arg);
1966 /* Option not recognized */
1970 *log_msgptr = string_sprintf("unknown option \"%s\" in ACL "
1971 "condition \"verify %s\"", ss, arg);
1976 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster)) ==
1977 (vopt_callout_recipsender|vopt_callout_recippmaster))
1979 *log_msgptr = US"only one of use_sender and use_postmaster can be set "
1980 "for a recipient callout";
1984 /* Handle sender-in-header verification. Default the user message to the log
1985 message if giving out verification details. */
1987 if (verify_header_sender)
1990 rc = verify_check_header_address(user_msgptr, log_msgptr, callout,
1991 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, verify_options,
1995 *basic_errno = verrno;
1996 if (smtp_return_error_details)
1998 if (*user_msgptr == NULL && *log_msgptr != NULL)
1999 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
2000 if (rc == DEFER) acl_temp_details = TRUE;
2005 /* Handle a sender address. The default is to verify *the* sender address, but
2006 optionally a different address can be given, for special requirements. If the
2007 address is empty, we are dealing with a bounce message that has no sender, so
2008 we cannot do any checking. If the real sender address gets rewritten during
2009 verification (e.g. DNS widening), set the flag to stop it being rewritten again
2010 during message reception.
2012 A list of verified "sender" addresses is kept to try to avoid doing to much
2013 work repetitively when there are multiple recipients in a message and they all
2014 require sender verification. However, when callouts are involved, it gets too
2015 complicated because different recipients may require different callout options.
2016 Therefore, we always do a full sender verify when any kind of callout is
2017 specified. Caching elsewhere, for instance in the DNS resolver and in the
2018 callout handling, should ensure that this is not terribly inefficient. */
2020 else if (verify_sender_address != NULL)
2022 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster))
2025 *log_msgptr = US"use_sender or use_postmaster cannot be used for a "
2026 "sender verify callout";
2030 sender_vaddr = verify_checked_sender(verify_sender_address);
2031 if (sender_vaddr != NULL && /* Previously checked */
2032 callout <= 0) /* No callout needed this time */
2034 /* If the "routed" flag is set, it means that routing worked before, so
2035 this check can give OK (the saved return code value, if set, belongs to a
2036 callout that was done previously). If the "routed" flag is not set, routing
2037 must have failed, so we use the saved return code. */
2039 if (testflag(sender_vaddr, af_verify_routed)) rc = OK; else
2041 rc = sender_vaddr->special_action;
2042 *basic_errno = sender_vaddr->basic_errno;
2044 HDEBUG(D_acl) debug_printf("using cached sender verify result\n");
2047 /* Do a new verification, and cache the result. The cache is used to avoid
2048 verifying the sender multiple times for multiple RCPTs when callouts are not
2049 specified (see comments above).
2051 The cache is also used on failure to give details in response to the first
2052 RCPT that gets bounced for this reason. However, this can be suppressed by
2053 the no_details option, which sets the flag that says "this detail has already
2054 been sent". The cache normally contains just one address, but there may be
2055 more in esoteric circumstances. */
2060 uschar *save_address_data = deliver_address_data;
2062 sender_vaddr = deliver_make_addr(verify_sender_address, TRUE);
2063 if (no_details) setflag(sender_vaddr, af_sverify_told);
2064 if (verify_sender_address[0] != 0)
2066 /* If this is the real sender address, save the unrewritten version
2067 for use later in receive. Otherwise, set a flag so that rewriting the
2068 sender in verify_address() does not update sender_address. */
2070 if (verify_sender_address == sender_address)
2071 sender_address_unrewritten = sender_address;
2073 verify_options |= vopt_fake_sender;
2075 if (success_on_redirect)
2076 verify_options |= vopt_success_on_redirect;
2078 /* The recipient, qualify, and expn options are never set in
2081 rc = verify_address(sender_vaddr, NULL, verify_options, callout,
2082 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, &routed);
2084 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
2088 if (Ustrcmp(sender_vaddr->address, verify_sender_address) != 0)
2090 DEBUG(D_acl) debug_printf("sender %s verified ok as %s\n",
2091 verify_sender_address, sender_vaddr->address);
2095 DEBUG(D_acl) debug_printf("sender %s verified ok\n",
2096 verify_sender_address);
2099 else *basic_errno = sender_vaddr->basic_errno;
2101 else rc = OK; /* Null sender */
2103 /* Cache the result code */
2105 if (routed) setflag(sender_vaddr, af_verify_routed);
2106 if (callout > 0) setflag(sender_vaddr, af_verify_callout);
2107 sender_vaddr->special_action = rc;
2108 sender_vaddr->next = sender_verified_list;
2109 sender_verified_list = sender_vaddr;
2111 /* Restore the recipient address data, which might have been clobbered by
2112 the sender verification. */
2114 deliver_address_data = save_address_data;
2117 /* Put the sender address_data value into $sender_address_data */
2119 sender_address_data = sender_vaddr->p.address_data;
2122 /* A recipient address just gets a straightforward verify; again we must handle
2123 the DEFER overrides. */
2129 if (success_on_redirect)
2130 verify_options |= vopt_success_on_redirect;
2132 /* We must use a copy of the address for verification, because it might
2136 rc = verify_address(&addr2, NULL, verify_options|vopt_is_recipient, callout,
2137 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, NULL);
2138 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
2140 *basic_errno = addr2.basic_errno;
2141 *log_msgptr = addr2.message;
2142 *user_msgptr = (addr2.user_message != NULL)?
2143 addr2.user_message : addr2.message;
2145 /* Allow details for temporary error if the address is so flagged. */
2146 if (testflag((&addr2), af_pass_message)) acl_temp_details = TRUE;
2148 /* Make $address_data visible */
2149 deliver_address_data = addr2.p.address_data;
2152 /* We have a result from the relevant test. Handle defer overrides first. */
2154 if (rc == DEFER && (defer_ok ||
2155 (callout_defer_ok && *basic_errno == ERRNO_CALLOUTDEFER)))
2157 HDEBUG(D_acl) debug_printf("verify defer overridden by %s\n",
2158 defer_ok? "defer_ok" : "callout_defer_ok");
2162 /* If we've failed a sender, set up a recipient message, and point
2163 sender_verified_failed to the address item that actually failed. */
2165 if (rc != OK && verify_sender_address != NULL)
2169 *log_msgptr = *user_msgptr = US"Sender verify failed";
2171 else if (*basic_errno != ERRNO_CALLOUTDEFER)
2173 *log_msgptr = *user_msgptr = US"Could not complete sender verify";
2177 *log_msgptr = US"Could not complete sender verify callout";
2178 *user_msgptr = smtp_return_error_details? sender_vaddr->user_message :
2182 sender_verified_failed = sender_vaddr;
2185 /* Verifying an address messes up the values of $domain and $local_part,
2186 so reset them before returning if this is a RCPT ACL. */
2190 deliver_domain = addr->domain;
2191 deliver_localpart = addr->local_part;
2195 /* Syntax errors in the verify argument come here. */
2198 *log_msgptr = string_sprintf("expected \"sender[=address]\", \"recipient\", "
2199 "\"helo\", \"header_syntax\", \"header_sender\" or "
2200 "\"reverse_host_lookup\" at start of ACL condition "
2201 "\"verify %s\"", arg);
2208 /*************************************************
2209 * Check argument for control= modifier *
2210 *************************************************/
2212 /* Called from acl_check_condition() below
2215 arg the argument string for control=
2216 pptr set to point to the terminating character
2217 where which ACL we are in
2218 log_msgptr for error messages
2220 Returns: CONTROL_xxx value
2224 decode_control(uschar *arg, uschar **pptr, int where, uschar **log_msgptr)
2229 for (d = controls_list;
2230 d < controls_list + sizeof(controls_list)/sizeof(control_def);
2233 len = Ustrlen(d->name);
2234 if (Ustrncmp(d->name, arg, len) == 0) break;
2237 if (d >= controls_list + sizeof(controls_list)/sizeof(control_def) ||
2238 (arg[len] != 0 && (!d->has_option || arg[len] != '/')))
2240 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
2241 return CONTROL_ERROR;
2251 /*************************************************
2252 * Return a ratelimit error *
2253 *************************************************/
2255 /* Called from acl_ratelimit() below
2258 log_msgptr for error messages
2259 format format string
2260 ... supplementary arguments
2261 ss ratelimit option name
2262 where ACL_WHERE_xxxx indicating which ACL this is
2268 ratelimit_error(uschar **log_msgptr, const char *format, ...)
2271 uschar buffer[STRING_SPRINTF_BUFFER_SIZE];
2272 va_start(ap, format);
2273 if (!string_vformat(buffer, sizeof(buffer), format, ap))
2274 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
2275 "string_sprintf expansion was longer than " SIZE_T_FMT, sizeof(buffer));
2277 *log_msgptr = string_sprintf(
2278 "error in arguments to \"ratelimit\" condition: %s", buffer);
2285 /*************************************************
2286 * Handle rate limiting *
2287 *************************************************/
2289 /* Called by acl_check_condition() below to calculate the result
2290 of the ACL ratelimit condition.
2292 Note that the return value might be slightly unexpected: if the
2293 sender's rate is above the limit then the result is OK. This is
2294 similar to the dnslists condition, and is so that you can write
2295 ACL clauses like: defer ratelimit = 15 / 1h
2298 arg the option string for ratelimit=
2299 where ACL_WHERE_xxxx indicating which ACL this is
2300 log_msgptr for error messages
2302 Returns: OK - Sender's rate is above limit
2303 FAIL - Sender's rate is below limit
2304 DEFER - Problem opening ratelimit database
2305 ERROR - Syntax error in options.
2309 acl_ratelimit(uschar *arg, int where, uschar **log_msgptr)
2311 double limit, period, count;
2314 uschar *unique = NULL;
2316 BOOL leaky = FALSE, strict = FALSE, readonly = FALSE;
2317 BOOL noupdate = FALSE, badacl = FALSE;
2318 int mode = RATE_PER_WHAT;
2320 tree_node **anchor, *t;
2321 open_db dbblock, *dbm;
2323 dbdata_ratelimit *dbd;
2324 dbdata_ratelimit_unique *dbdb;
2327 /* Parse the first two options and record their values in expansion
2328 variables. These variables allow the configuration to have informative
2329 error messages based on rate limits obtained from a table lookup. */
2331 /* First is the maximum number of messages per period / maximum burst
2332 size, which must be greater than or equal to zero. Zero is useful for
2333 rate measurement as opposed to rate limiting. */
2335 sender_rate_limit = string_nextinlist(&arg, &sep, NULL, 0);
2336 if (sender_rate_limit == NULL)
2340 limit = Ustrtod(sender_rate_limit, &ss);
2341 if (tolower(*ss) == 'k') { limit *= 1024.0; ss++; }
2342 else if (tolower(*ss) == 'm') { limit *= 1024.0*1024.0; ss++; }
2343 else if (tolower(*ss) == 'g') { limit *= 1024.0*1024.0*1024.0; ss++; }
2345 if (limit < 0.0 || *ss != '\0')
2346 return ratelimit_error(log_msgptr,
2347 "\"%s\" is not a positive number", sender_rate_limit);
2349 /* Second is the rate measurement period / exponential smoothing time
2350 constant. This must be strictly greater than zero, because zero leads to
2351 run-time division errors. */
2353 sender_rate_period = string_nextinlist(&arg, &sep, NULL, 0);
2354 if (sender_rate_period == NULL) period = -1.0;
2355 else period = readconf_readtime(sender_rate_period, 0, FALSE);
2357 return ratelimit_error(log_msgptr,
2358 "\"%s\" is not a time value", sender_rate_period);
2360 /* By default we are counting one of something, but the per_rcpt,
2361 per_byte, and count options can change this. */
2365 /* Parse the other options. */
2367 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2370 if (strcmpic(ss, US"leaky") == 0) leaky = TRUE;
2371 else if (strcmpic(ss, US"strict") == 0) strict = TRUE;
2372 else if (strcmpic(ss, US"noupdate") == 0) noupdate = TRUE;
2373 else if (strcmpic(ss, US"readonly") == 0) readonly = TRUE;
2374 else if (strcmpic(ss, US"per_cmd") == 0) RATE_SET(mode, PER_CMD);
2375 else if (strcmpic(ss, US"per_conn") == 0)
2377 RATE_SET(mode, PER_CONN);
2378 if (where == ACL_WHERE_NOTSMTP || where == ACL_WHERE_NOTSMTP_START)
2381 else if (strcmpic(ss, US"per_mail") == 0)
2383 RATE_SET(mode, PER_MAIL);
2384 if (where > ACL_WHERE_NOTSMTP) badacl = TRUE;
2386 else if (strcmpic(ss, US"per_rcpt") == 0)
2388 /* If we are running in the RCPT ACL, then we'll count the recipients
2389 one by one, but if we are running when we have accumulated the whole
2390 list then we'll add them all in one batch. */
2391 if (where == ACL_WHERE_RCPT)
2392 RATE_SET(mode, PER_RCPT);
2393 else if (where >= ACL_WHERE_PREDATA && where <= ACL_WHERE_NOTSMTP)
2394 RATE_SET(mode, PER_ALLRCPTS), count = (double)recipients_count;
2395 else if (where == ACL_WHERE_MAIL || where > ACL_WHERE_NOTSMTP)
2396 RATE_SET(mode, PER_RCPT), badacl = TRUE;
2398 else if (strcmpic(ss, US"per_byte") == 0)
2400 /* If we have not yet received the message data and there was no SIZE
2401 declaration on the MAIL comand, then it's safe to just use a value of
2402 zero and let the recorded rate decay as if nothing happened. */
2403 RATE_SET(mode, PER_MAIL);
2404 if (where > ACL_WHERE_NOTSMTP) badacl = TRUE;
2405 else count = message_size < 0 ? 0.0 : (double)message_size;
2407 else if (strcmpic(ss, US"per_addr") == 0)
2409 RATE_SET(mode, PER_RCPT);
2410 if (where != ACL_WHERE_RCPT) badacl = TRUE, unique = US"*";
2411 else unique = string_sprintf("%s@%s", deliver_localpart, deliver_domain);
2413 else if (strncmpic(ss, US"count=", 6) == 0)
2416 count = Ustrtod(ss+6, &e);
2417 if (count < 0.0 || *e != '\0')
2418 return ratelimit_error(log_msgptr,
2419 "\"%s\" is not a positive number", ss);
2421 else if (strncmpic(ss, US"unique=", 7) == 0)
2422 unique = string_copy(ss + 7);
2423 else if (key == NULL)
2424 key = string_copy(ss);
2426 key = string_sprintf("%s/%s", key, ss);
2429 /* Sanity check. When the badacl flag is set the update mode must either
2430 be readonly (which is the default if it is omitted) or, for backwards
2431 compatibility, a combination of noupdate and strict or leaky. */
2433 if (mode == RATE_PER_CLASH)
2434 return ratelimit_error(log_msgptr, "conflicting per_* options");
2435 if (leaky + strict + readonly > 1)
2436 return ratelimit_error(log_msgptr, "conflicting update modes");
2437 if (badacl && (leaky || strict) && !noupdate)
2438 return ratelimit_error(log_msgptr,
2439 "\"%s\" must not have /leaky or /strict option in %s ACL",
2440 ratelimit_option_string[mode], acl_wherenames[where]);
2442 /* Set the default values of any unset options. In readonly mode we
2443 perform the rate computation without any increment so that its value
2444 decays to eventually allow over-limit senders through. */
2446 if (noupdate) readonly = TRUE, leaky = strict = FALSE;
2447 if (badacl) readonly = TRUE;
2448 if (readonly) count = 0.0;
2449 if (!strict && !readonly) leaky = TRUE;
2450 if (mode == RATE_PER_WHAT) mode = RATE_PER_MAIL;
2452 /* Create the lookup key. If there is no explicit key, use sender_host_address.
2453 If there is no sender_host_address (e.g. -bs or acl_not_smtp) then we simply
2454 omit it. The smoothing constant (sender_rate_period) and the per_xxx options
2455 are added to the key because they alter the meaning of the stored data. */
2458 key = (sender_host_address == NULL)? US"" : sender_host_address;
2460 key = string_sprintf("%s/%s/%s%s",
2462 ratelimit_option_string[mode],
2463 unique == NULL ? "" : "unique/",
2467 debug_printf("ratelimit condition count=%.0f %.1f/%s\n", count, limit, key);
2469 /* See if we have already computed the rate by looking in the relevant tree.
2470 For per-connection rate limiting, store tree nodes and dbdata in the permanent
2471 pool so that they survive across resets. In readonly mode we only remember the
2472 result for the rest of this command in case a later command changes it. After
2473 this bit of logic the code is independent of the per_* mode. */
2475 old_pool = store_pool;
2478 anchor = &ratelimiters_cmd;
2481 anchor = &ratelimiters_conn;
2482 store_pool = POOL_PERM;
2486 case RATE_PER_ALLRCPTS:
2487 anchor = &ratelimiters_mail;
2492 anchor = &ratelimiters_cmd;
2495 anchor = NULL; /* silence an "unused" complaint */
2496 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
2497 "internal ACL error: unknown ratelimit mode %d", mode);
2501 t = tree_search(*anchor, key);
2505 /* The following few lines duplicate some of the code below. */
2506 rc = (dbd->rate < limit)? FAIL : OK;
2507 store_pool = old_pool;
2508 sender_rate = string_sprintf("%.1f", dbd->rate);
2510 debug_printf("ratelimit found pre-computed rate %s\n", sender_rate);
2514 /* We aren't using a pre-computed rate, so get a previously recorded rate
2515 from the database, which will be updated and written back if required. */
2517 dbm = dbfn_open(US"ratelimit", O_RDWR, &dbblock, TRUE);
2520 store_pool = old_pool;
2522 HDEBUG(D_acl) debug_printf("ratelimit database not available\n");
2523 *log_msgptr = US"ratelimit database not available";
2526 dbdb = dbfn_read_with_length(dbm, key, &dbdb_size);
2529 gettimeofday(&tv, NULL);
2533 /* Locate the basic ratelimit block inside the DB data. */
2534 HDEBUG(D_acl) debug_printf("ratelimit found key in database\n");
2537 /* Forget the old Bloom filter if it is too old, so that we count each
2538 repeating event once per period. We don't simply clear and re-use the old
2539 filter because we want its size to change if the limit changes. Note that
2540 we keep the dbd pointer for copying the rate into the new data block. */
2542 if(unique != NULL && tv.tv_sec > dbdb->bloom_epoch + period)
2544 HDEBUG(D_acl) debug_printf("ratelimit discarding old Bloom filter\n");
2550 if(unique != NULL && dbdb_size < sizeof(*dbdb))
2552 HDEBUG(D_acl) debug_printf("ratelimit discarding undersize Bloom filter\n");
2557 /* Allocate a new data block if the database lookup failed
2558 or the Bloom filter passed its age limit. */
2564 /* No Bloom filter. This basic ratelimit block is initialized below. */
2565 HDEBUG(D_acl) debug_printf("ratelimit creating new rate data block\n");
2566 dbdb_size = sizeof(*dbd);
2567 dbdb = store_get(dbdb_size);
2572 HDEBUG(D_acl) debug_printf("ratelimit creating new Bloom filter\n");
2574 /* See the long comment below for an explanation of the magic number 2.
2575 The filter has a minimum size in case the rate limit is very small;
2576 this is determined by the definition of dbdata_ratelimit_unique. */
2578 extra = (int)limit * 2 - sizeof(dbdb->bloom);
2579 if (extra < 0) extra = 0;
2580 dbdb_size = sizeof(*dbdb) + extra;
2581 dbdb = store_get(dbdb_size);
2582 dbdb->bloom_epoch = tv.tv_sec;
2583 dbdb->bloom_size = sizeof(dbdb->bloom) + extra;
2584 memset(dbdb->bloom, 0, dbdb->bloom_size);
2586 /* Preserve any basic ratelimit data (which is our longer-term memory)
2587 by copying it from the discarded block. */
2597 /* If we are counting unique events, find out if this event is new or not.
2598 If the client repeats the event during the current period then it should be
2599 counted. We skip this code in readonly mode for efficiency, because any
2600 changes to the filter will be discarded and because count is already set to
2603 if (unique != NULL && !readonly)
2605 /* We identify unique events using a Bloom filter. (You can find my
2606 notes on Bloom filters at http://fanf.livejournal.com/81696.html)
2607 With the per_addr option, an "event" is a recipient address, though the
2608 user can use the unique option to define their own events. We only count
2609 an event if we have not seen it before.
2611 We size the filter according to the rate limit, which (in leaky mode)
2612 is the limit on the population of the filter. We allow 16 bits of space
2613 per entry (see the construction code above) and we set (up to) 8 of them
2614 when inserting an element (see the loop below). The probability of a false
2615 positive (an event we have not seen before but which we fail to count) is
2619 allzero = exp(-numhash * pop / size)
2620 = exp(-0.5 * pop / limit)
2621 fpr = pow(1 - allzero, numhash)
2623 For senders at the limit the fpr is 0.06% or 1 in 1700
2624 and for senders at half the limit it is 0.0006% or 1 in 170000
2626 In strict mode the Bloom filter can fill up beyond the normal limit, in
2627 which case the false positive rate will rise. This means that the
2628 measured rate for very fast senders can bogusly drop off after a while.
2630 At twice the limit, the fpr is 2.5% or 1 in 40
2631 At four times the limit, it is 31% or 1 in 3.2
2633 It takes ln(pop/limit) periods for an over-limit burst of pop events to
2634 decay below the limit, and if this is more than one then the Bloom filter
2635 will be discarded before the decay gets that far. The false positive rate
2636 at this threshold is 9.3% or 1 in 10.7. */
2639 unsigned n, hash, hinc;
2643 /* Instead of using eight independent hash values, we combine two values
2644 using the formula h1 + n * h2. This does not harm the Bloom filter's
2645 performance, and means the amount of hash we need is independent of the
2646 number of bits we set in the filter. */
2648 md5_start(&md5info);
2649 md5_end(&md5info, unique, Ustrlen(unique), md5sum);
2650 hash = md5sum[0] | md5sum[1] << 8 | md5sum[2] << 16 | md5sum[3] << 24;
2651 hinc = md5sum[4] | md5sum[5] << 8 | md5sum[6] << 16 | md5sum[7] << 24;
2653 /* Scan the bits corresponding to this event. A zero bit means we have
2654 not seen it before. Ensure all bits are set to record this event. */
2656 HDEBUG(D_acl) debug_printf("ratelimit checking uniqueness of %s\n", unique);
2659 for (n = 0; n < 8; n++, hash += hinc)
2661 int bit = 1 << (hash % 8);
2662 int byte = (hash / 8) % dbdb->bloom_size;
2663 if ((dbdb->bloom[byte] & bit) == 0)
2665 dbdb->bloom[byte] |= bit;
2670 /* If this event has occurred before, do not count it. */
2674 HDEBUG(D_acl) debug_printf("ratelimit event found in Bloom filter\n");
2678 HDEBUG(D_acl) debug_printf("ratelimit event added to Bloom filter\n");
2681 /* If there was no previous ratelimit data block for this key, initialize
2682 the new one, otherwise update the block from the database. The initial rate
2683 is what would be computed by the code below for an infinite interval. */
2687 HDEBUG(D_acl) debug_printf("ratelimit initializing new key's rate data\n");
2689 dbd->time_stamp = tv.tv_sec;
2690 dbd->time_usec = tv.tv_usec;
2695 /* The smoothed rate is computed using an exponentially weighted moving
2696 average adjusted for variable sampling intervals. The standard EWMA for
2697 a fixed sampling interval is: f'(t) = (1 - a) * f(t) + a * f'(t - 1)
2698 where f() is the measured value and f'() is the smoothed value.
2700 Old data decays out of the smoothed value exponentially, such that data n
2701 samples old is multiplied by a^n. The exponential decay time constant p
2702 is defined such that data p samples old is multiplied by 1/e, which means
2703 that a = exp(-1/p). We can maintain the same time constant for a variable
2704 sampling interval i by using a = exp(-i/p).
2706 The rate we are measuring is messages per period, suitable for directly
2707 comparing with the limit. The average rate between now and the previous
2708 message is period / interval, which we feed into the EWMA as the sample.
2710 It turns out that the number of messages required for the smoothed rate
2711 to reach the limit when they are sent in a burst is equal to the limit.
2712 This can be seen by analysing the value of the smoothed rate after N
2713 messages sent at even intervals. Let k = (1 - a) * p/i
2715 rate_1 = (1 - a) * p/i + a * rate_0
2717 rate_2 = k + a * rate_1
2718 = k + a * k + a^2 * rate_0
2719 rate_3 = k + a * k + a^2 * k + a^3 * rate_0
2720 rate_N = rate_0 * a^N + k * SUM(x=0..N-1)(a^x)
2721 = rate_0 * a^N + k * (1 - a^N) / (1 - a)
2722 = rate_0 * a^N + p/i * (1 - a^N)
2724 When N is large, a^N -> 0 so rate_N -> p/i as desired.
2726 rate_N = p/i + (rate_0 - p/i) * a^N
2727 a^N = (rate_N - p/i) / (rate_0 - p/i)
2728 N * -i/p = log((rate_N - p/i) / (rate_0 - p/i))
2729 N = p/i * log((rate_0 - p/i) / (rate_N - p/i))
2731 Numerical analysis of the above equation, setting the computed rate to
2732 increase from rate_0 = 0 to rate_N = limit, shows that for large sending
2733 rates, p/i, the number of messages N = limit. So limit serves as both the
2734 maximum rate measured in messages per period, and the maximum number of
2735 messages that can be sent in a fast burst. */
2737 double this_time = (double)tv.tv_sec
2738 + (double)tv.tv_usec / 1000000.0;
2739 double prev_time = (double)dbd->time_stamp
2740 + (double)dbd->time_usec / 1000000.0;
2742 /* We must avoid division by zero, and deal gracefully with the clock going
2743 backwards. If we blunder ahead when time is in reverse then the computed
2744 rate will be bogus. To be safe we clamp interval to a very small number. */
2746 double interval = this_time - prev_time <= 0.0 ? 1e-9
2747 : this_time - prev_time;
2749 double i_over_p = interval / period;
2750 double a = exp(-i_over_p);
2752 /* Combine the instantaneous rate (period / interval) with the previous rate
2753 using the smoothing factor a. In order to measure sized events, multiply the
2754 instantaneous rate by the count of bytes or recipients etc. */
2756 dbd->time_stamp = tv.tv_sec;
2757 dbd->time_usec = tv.tv_usec;
2758 dbd->rate = (1 - a) * count / i_over_p + a * dbd->rate;
2760 /* When events are very widely spaced the computed rate tends towards zero.
2761 Although this is accurate it turns out not to be useful for our purposes,
2762 especially when the first event after a long silence is the start of a spam
2763 run. A more useful model is that the rate for an isolated event should be the
2764 size of the event per the period size, ignoring the lack of events outside
2765 the current period and regardless of where the event falls in the period. So,
2766 if the interval was so long that the calculated rate is unhelpfully small, we
2767 re-intialize the rate. In the absence of higher-rate bursts, the condition
2768 below is true if the interval is greater than the period. */
2770 if (dbd->rate < count) dbd->rate = count;
2773 /* Clients sending at the limit are considered to be over the limit.
2774 This matters for edge cases such as a limit of zero, when the client
2775 should be completely blocked. */
2777 rc = (dbd->rate < limit)? FAIL : OK;
2779 /* Update the state if the rate is low or if we are being strict. If we
2780 are in leaky mode and the sender's rate is too high, we do not update
2781 the recorded rate in order to avoid an over-aggressive sender's retry
2782 rate preventing them from getting any email through. If readonly is set,
2783 neither leaky nor strict are set, so we do not do any updates. */
2785 if ((rc == FAIL && leaky) || strict)
2787 dbfn_write(dbm, key, dbdb, dbdb_size);
2788 HDEBUG(D_acl) debug_printf("ratelimit db updated\n");
2792 HDEBUG(D_acl) debug_printf("ratelimit db not updated: %s\n",
2793 readonly? "readonly mode" : "over the limit, but leaky");
2798 /* Store the result in the tree for future reference. */
2800 t = store_get(sizeof(tree_node) + Ustrlen(key));
2802 Ustrcpy(t->name, key);
2803 (void)tree_insertnode(anchor, t);
2805 /* We create the formatted version of the sender's rate very late in
2806 order to ensure that it is done using the correct storage pool. */
2808 store_pool = old_pool;
2809 sender_rate = string_sprintf("%.1f", dbd->rate);
2812 debug_printf("ratelimit computed rate %s\n", sender_rate);
2819 /*************************************************
2820 * Handle conditions/modifiers on an ACL item *
2821 *************************************************/
2823 /* Called from acl_check() below.
2827 cb ACL condition block - if NULL, result is OK
2828 where where called from
2829 addr the address being checked for RCPT, or NULL
2830 level the nesting level
2831 epp pointer to pass back TRUE if "endpass" encountered
2832 (applies only to "accept" and "discard")
2833 user_msgptr user message pointer
2834 log_msgptr log message pointer
2835 basic_errno pointer to where to put verify error
2837 Returns: OK - all conditions are met
2838 DISCARD - an "acl" condition returned DISCARD - only allowed
2839 for "accept" or "discard" verbs
2840 FAIL - at least one condition fails
2841 FAIL_DROP - an "acl" condition returned FAIL_DROP
2842 DEFER - can't tell at the moment (typically, lookup defer,
2843 but can be temporary callout problem)
2844 ERROR - ERROR from nested ACL or expansion failure or other
2849 acl_check_condition(int verb, acl_condition_block *cb, int where,
2850 address_item *addr, int level, BOOL *epp, uschar **user_msgptr,
2851 uschar **log_msgptr, int *basic_errno)
2853 uschar *user_message = NULL;
2854 uschar *log_message = NULL;
2855 uschar *debug_tag = NULL;
2856 uschar *debug_opts = NULL;
2859 #ifdef WITH_CONTENT_SCAN
2863 for (; cb != NULL; cb = cb->next)
2868 /* The message and log_message items set up messages to be used in
2869 case of rejection. They are expanded later. */
2871 if (cb->type == ACLC_MESSAGE)
2873 user_message = cb->arg;
2877 if (cb->type == ACLC_LOG_MESSAGE)
2879 log_message = cb->arg;
2883 /* The endpass "condition" just sets a flag to show it occurred. This is
2884 checked at compile time to be on an "accept" or "discard" item. */
2886 if (cb->type == ACLC_ENDPASS)
2892 /* For other conditions and modifiers, the argument is expanded now for some
2893 of them, but not for all, because expansion happens down in some lower level
2894 checking functions in some cases. */
2896 if (cond_expand_at_top[cb->type])
2898 arg = expand_string(cb->arg);
2901 if (expand_string_forcedfail) continue;
2902 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s",
2903 cb->arg, expand_string_message);
2904 return search_find_defer? DEFER : ERROR;
2909 /* Show condition, and expanded condition if it's different */
2914 debug_printf("check %s%s %n",
2915 (!cond_modifiers[cb->type] && cb->u.negated)? "!":"",
2916 conditions[cb->type], &lhswidth);
2918 if (cb->type == ACLC_SET)
2920 debug_printf("acl_%s ", cb->u.varname);
2921 lhswidth += 5 + Ustrlen(cb->u.varname);
2924 debug_printf("= %s\n", cb->arg);
2927 debug_printf("%.*s= %s\n", lhswidth,
2931 /* Check that this condition makes sense at this time */
2933 if ((cond_forbids[cb->type] & (1 << where)) != 0)
2935 *log_msgptr = string_sprintf("cannot %s %s condition in %s ACL",
2936 cond_modifiers[cb->type]? "use" : "test",
2937 conditions[cb->type], acl_wherenames[where]);
2941 /* Run the appropriate test for each condition, or take the appropriate
2942 action for the remaining modifiers. */
2946 case ACLC_ADD_HEADER:
2950 /* A nested ACL that returns "discard" makes sense only for an "accept" or
2954 rc = acl_check_wargs(where, addr, arg, level+1, user_msgptr, log_msgptr);
2955 if (rc == DISCARD && verb != ACL_ACCEPT && verb != ACL_DISCARD)
2957 *log_msgptr = string_sprintf("nested ACL returned \"discard\" for "
2958 "\"%s\" command (only allowed with \"accept\" or \"discard\")",
2964 case ACLC_AUTHENTICATED:
2965 rc = (sender_host_authenticated == NULL)? FAIL :
2966 match_isinlist(sender_host_authenticated, &arg, 0, NULL, NULL, MCL_STRING,
2970 #ifdef EXPERIMENTAL_BRIGHTMAIL
2971 case ACLC_BMI_OPTIN:
2973 int old_pool = store_pool;
2974 store_pool = POOL_PERM;
2975 bmi_current_optin = string_copy(arg);
2976 store_pool = old_pool;
2981 case ACLC_CONDITION:
2982 /* The true/false parsing here should be kept in sync with that used in
2983 expand.c when dealing with ECOND_BOOL so that we don't have too many
2984 different definitions of what can be a boolean. */
2985 if (Ustrspn(arg, "0123456789") == Ustrlen(arg)) /* Digits, or empty */
2986 rc = (Uatoi(arg) == 0)? FAIL : OK;
2988 rc = (strcmpic(arg, US"no") == 0 ||
2989 strcmpic(arg, US"false") == 0)? FAIL :
2990 (strcmpic(arg, US"yes") == 0 ||
2991 strcmpic(arg, US"true") == 0)? OK : DEFER;
2993 *log_msgptr = string_sprintf("invalid \"condition\" value \"%s\"", arg);
2996 case ACLC_CONTINUE: /* Always succeeds */
3000 control_type = decode_control(arg, &p, where, log_msgptr);
3002 /* Check if this control makes sense at this time */
3004 if ((control_forbids[control_type] & (1 << where)) != 0)
3006 *log_msgptr = string_sprintf("cannot use \"control=%s\" in %s ACL",
3007 controls[control_type], acl_wherenames[where]);
3011 switch(control_type)
3013 case CONTROL_AUTH_UNADVERTISED:
3014 allow_auth_unadvertised = TRUE;
3017 #ifdef EXPERIMENTAL_BRIGHTMAIL
3018 case CONTROL_BMI_RUN:
3023 #ifndef DISABLE_DKIM
3024 case CONTROL_DKIM_VERIFY:
3025 dkim_disable_verify = TRUE;
3026 #ifdef EXPERIMENTAL_DMARC
3027 /* Since DKIM was blocked, skip DMARC too */
3028 dmarc_disable_verify = TRUE;
3029 dmarc_enable_forensic = FALSE;
3034 #ifdef EXPERIMENTAL_DMARC
3035 case CONTROL_DMARC_VERIFY:
3036 dmarc_disable_verify = TRUE;
3039 case CONTROL_DMARC_FORENSIC:
3040 dmarc_enable_forensic = TRUE;
3047 int fd, af, level, optname, value;
3048 /* If we are acting on stdin, the setsockopt may fail if stdin is not
3049 a socket; we can accept that, we'll just debug-log failures anyway. */
3050 fd = fileno(smtp_in);
3051 af = ip_get_address_family(fd);
3055 debug_printf("smtp input is probably not a socket [%s], not setting DSCP\n",
3059 if (dscp_lookup(p+1, af, &level, &optname, &value))
3061 if (setsockopt(fd, level, optname, &value, sizeof(value)) < 0)
3063 HDEBUG(D_acl) debug_printf("failed to set input DSCP[%s]: %s\n",
3064 p+1, strerror(errno));
3068 HDEBUG(D_acl) debug_printf("set input DSCP to \"%s\"\n", p+1);
3073 *log_msgptr = string_sprintf("unrecognised DSCP value in \"control=%s\"", arg);
3079 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3087 case CONTROL_CASEFUL_LOCAL_PART:
3088 deliver_localpart = addr->cc_local_part;
3091 case CONTROL_CASELOWER_LOCAL_PART:
3092 deliver_localpart = addr->lc_local_part;
3095 case CONTROL_ENFORCE_SYNC:
3096 smtp_enforce_sync = TRUE;
3099 case CONTROL_NO_ENFORCE_SYNC:
3100 smtp_enforce_sync = FALSE;
3103 #ifdef WITH_CONTENT_SCAN
3104 case CONTROL_NO_MBOX_UNSPOOL:
3105 no_mbox_unspool = TRUE;
3109 case CONTROL_NO_MULTILINE:
3110 no_multiline_responses = TRUE;
3113 case CONTROL_NO_PIPELINING:
3114 pipelining_enable = FALSE;
3117 case CONTROL_NO_DELAY_FLUSH:
3118 disable_delay_flush = TRUE;
3121 case CONTROL_NO_CALLOUT_FLUSH:
3122 disable_callout_flush = TRUE;
3125 case CONTROL_FAKEDEFER:
3126 case CONTROL_FAKEREJECT:
3127 fake_response = (control_type == CONTROL_FAKEDEFER) ? DEFER : FAIL;
3131 while (*pp != 0) pp++;
3132 fake_response_text = expand_string(string_copyn(p+1, pp-p-1));
3137 /* Explicitly reset to default string */
3138 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).";
3142 case CONTROL_FREEZE:
3143 deliver_freeze = TRUE;
3144 deliver_frozen_at = time(NULL);
3145 freeze_tell = freeze_tell_config; /* Reset to configured value */
3146 if (Ustrncmp(p, "/no_tell", 8) == 0)
3153 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3158 case CONTROL_QUEUE_ONLY:
3159 queue_only_policy = TRUE;
3162 case CONTROL_SUBMISSION:
3163 originator_name = US"";
3164 submission_mode = TRUE;
3167 if (Ustrncmp(p, "/sender_retain", 14) == 0)
3170 active_local_sender_retain = TRUE;
3171 active_local_from_check = FALSE;
3173 else if (Ustrncmp(p, "/domain=", 8) == 0)
3176 while (*pp != 0 && *pp != '/') pp++;
3177 submission_domain = string_copyn(p+8, pp-p-8);
3180 /* The name= option must be last, because it swallows the rest of
3182 else if (Ustrncmp(p, "/name=", 6) == 0)
3185 while (*pp != 0) pp++;
3186 submission_name = string_copy(parse_fix_phrase(p+6, pp-p-6,
3187 big_buffer, big_buffer_size));
3194 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3202 if (Ustrncmp(p, "/tag=", 5) == 0)
3205 while (*pp != '\0' && *pp != '/') pp++;
3206 debug_tag = string_copyn(p+5, pp-p-5);
3209 else if (Ustrncmp(p, "/opts=", 6) == 0)
3212 while (*pp != '\0' && *pp != '/') pp++;
3213 debug_opts = string_copyn(p+6, pp-p-6);
3217 debug_logging_activate(debug_tag, debug_opts);
3220 case CONTROL_SUPPRESS_LOCAL_FIXUPS:
3221 suppress_local_fixups = TRUE;
3224 case CONTROL_CUTTHROUGH_DELIVERY:
3227 *log_msgptr = string_sprintf("\"control=%s\" on frozen item", arg);
3230 if (queue_only_policy)
3232 *log_msgptr = string_sprintf("\"control=%s\" on queue-only item", arg);
3235 cutthrough_delivery = TRUE;
3240 #ifdef EXPERIMENTAL_DCC
3243 /* Seperate the regular expression and any optional parameters. */
3244 uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size);
3245 /* Run the dcc backend. */
3246 rc = dcc_process(&ss);
3247 /* Modify return code based upon the existance of options. */
3248 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
3250 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
3252 /* FAIL so that the message is passed to the next ACL */
3260 #ifdef WITH_CONTENT_SCAN
3262 rc = mime_decode(&arg);
3268 int delay = readconf_readtime(arg, 0, FALSE);
3271 *log_msgptr = string_sprintf("syntax error in argument for \"delay\" "
3272 "modifier: \"%s\" is not a time value", arg);
3277 HDEBUG(D_acl) debug_printf("delay modifier requests %d-second delay\n",
3282 debug_printf("delay skipped in -bh checking mode\n");
3285 /* It appears to be impossible to detect that a TCP/IP connection has
3286 gone away without reading from it. This means that we cannot shorten
3287 the delay below if the client goes away, because we cannot discover
3288 that the client has closed its end of the connection. (The connection
3289 is actually in a half-closed state, waiting for the server to close its
3290 end.) It would be nice to be able to detect this state, so that the
3291 Exim process is not held up unnecessarily. However, it seems that we
3292 can't. The poll() function does not do the right thing, and in any case
3293 it is not always available.
3295 NOTE 1: If ever this state of affairs changes, remember that we may be
3296 dealing with stdin/stdout here, in addition to TCP/IP connections.
3297 Also, delays may be specified for non-SMTP input, where smtp_out and
3298 smtp_in will be NULL. Whatever is done must work in all cases.
3300 NOTE 2: The added feature of flushing the output before a delay must
3301 apply only to SMTP input. Hence the test for smtp_out being non-NULL.
3306 if (smtp_out != NULL && !disable_delay_flush) mac_smtp_fflush();
3307 while (delay > 0) delay = sleep(delay);
3313 #ifdef WITH_OLD_DEMIME
3319 #ifndef DISABLE_DKIM
3320 case ACLC_DKIM_SIGNER:
3321 if (dkim_cur_signer != NULL)
3322 rc = match_isinlist(dkim_cur_signer,
3323 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
3328 case ACLC_DKIM_STATUS:
3329 rc = match_isinlist(dkim_exim_expand_query(DKIM_VERIFY_STATUS),
3330 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
3334 #ifdef EXPERIMENTAL_DMARC
3335 case ACLC_DMARC_STATUS:
3336 if (!dmarc_has_been_checked)
3338 dmarc_has_been_checked = TRUE;
3339 /* used long way of dmarc_exim_expand_query() in case we need more
3340 * view into the process in the future. */
3341 rc = match_isinlist(dmarc_exim_expand_query(DMARC_VERIFY_STATUS),
3342 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
3347 rc = verify_check_dnsbl(&arg);
3351 rc = match_isinlist(addr->domain, &arg, 0, &domainlist_anchor,
3352 addr->domain_cache, MCL_DOMAIN, TRUE, &deliver_domain_data);
3355 /* The value in tls_cipher is the full cipher name, for example,
3356 TLSv1:DES-CBC3-SHA:168, whereas the values to test for are just the
3357 cipher names such as DES-CBC3-SHA. But program defensively. We don't know
3358 what may in practice come out of the SSL library - which at the time of
3359 writing is poorly documented. */
3361 case ACLC_ENCRYPTED:
3362 if (tls_in.cipher == NULL) rc = FAIL; else
3364 uschar *endcipher = NULL;
3365 uschar *cipher = Ustrchr(tls_in.cipher, ':');
3366 if (cipher == NULL) cipher = tls_in.cipher; else
3368 endcipher = Ustrchr(++cipher, ':');
3369 if (endcipher != NULL) *endcipher = 0;
3371 rc = match_isinlist(cipher, &arg, 0, NULL, NULL, MCL_STRING, TRUE, NULL);
3372 if (endcipher != NULL) *endcipher = ':';
3376 /* Use verify_check_this_host() instead of verify_check_host() so that
3377 we can pass over &host_data to catch any looked up data. Once it has been
3378 set, it retains its value so that it's still there if another ACL verb
3379 comes through here and uses the cache. However, we must put it into
3380 permanent store in case it is also expected to be used in a subsequent
3381 message in the same SMTP connection. */
3384 rc = verify_check_this_host(&arg, sender_host_cache, NULL,
3385 (sender_host_address == NULL)? US"" : sender_host_address, &host_data);
3386 if (host_data != NULL) host_data = string_copy_malloc(host_data);
3389 case ACLC_LOCAL_PARTS:
3390 rc = match_isinlist(addr->cc_local_part, &arg, 0,
3391 &localpartlist_anchor, addr->localpart_cache, MCL_LOCALPART, TRUE,
3392 &deliver_localpart_data);
3395 case ACLC_LOG_REJECT_TARGET:
3401 while ((ss = string_nextinlist(&s, &sep, big_buffer, big_buffer_size))
3404 if (Ustrcmp(ss, "main") == 0) logbits |= LOG_MAIN;
3405 else if (Ustrcmp(ss, "panic") == 0) logbits |= LOG_PANIC;
3406 else if (Ustrcmp(ss, "reject") == 0) logbits |= LOG_REJECT;
3409 logbits |= LOG_MAIN|LOG_REJECT;
3410 log_write(0, LOG_MAIN|LOG_PANIC, "unknown log name \"%s\" in "
3411 "\"log_reject_target\" in %s ACL", ss, acl_wherenames[where]);
3414 log_reject_target = logbits;
3427 if (Ustrncmp(s, "main", 4) == 0)
3428 { logbits |= LOG_MAIN; s += 4; }
3429 else if (Ustrncmp(s, "panic", 5) == 0)
3430 { logbits |= LOG_PANIC; s += 5; }
3431 else if (Ustrncmp(s, "reject", 6) == 0)
3432 { logbits |= LOG_REJECT; s += 6; }
3435 logbits = LOG_MAIN|LOG_PANIC;
3436 s = string_sprintf(":unknown log name in \"%s\" in "
3437 "\"logwrite\" in %s ACL", arg, acl_wherenames[where]);
3443 while (isspace(*s)) s++;
3446 if (logbits == 0) logbits = LOG_MAIN;
3447 log_write(0, logbits, "%s", string_printing(s));
3451 #ifdef WITH_CONTENT_SCAN
3454 /* Separate the regular expression and any optional parameters. */
3455 uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size);
3456 /* Run the malware backend. */
3458 /* Modify return code based upon the existance of options. */
3459 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
3461 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
3463 /* FAIL so that the message is passed to the next ACL */
3470 case ACLC_MIME_REGEX:
3471 rc = mime_regex(&arg);
3475 case ACLC_RATELIMIT:
3476 rc = acl_ratelimit(arg, where, log_msgptr);
3479 case ACLC_RECIPIENTS:
3480 rc = match_address_list(addr->address, TRUE, TRUE, &arg, NULL, -1, 0,
3484 #ifdef WITH_CONTENT_SCAN
3490 case ACLC_REMOVE_HEADER:
3491 setup_remove_header(arg);
3494 case ACLC_SENDER_DOMAINS:
3497 sdomain = Ustrrchr(sender_address, '@');
3498 sdomain = (sdomain == NULL)? US"" : sdomain + 1;
3499 rc = match_isinlist(sdomain, &arg, 0, &domainlist_anchor,
3500 sender_domain_cache, MCL_DOMAIN, TRUE, NULL);
3505 rc = match_address_list(sender_address, TRUE, TRUE, &arg,
3506 sender_address_cache, -1, 0, &sender_data);
3509 /* Connection variables must persist forever */
3513 int old_pool = store_pool;
3514 if (cb->u.varname[0] == 'c') store_pool = POOL_PERM;
3515 acl_var_create(cb->u.varname)->data.ptr = string_copy(arg);
3516 store_pool = old_pool;
3520 #ifdef WITH_CONTENT_SCAN
3523 /* Seperate the regular expression and any optional parameters. */
3524 uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size);
3525 /* Run the spam backend. */
3527 /* Modify return code based upon the existance of options. */
3528 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
3530 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
3532 /* FAIL so that the message is passed to the next ACL */
3540 #ifdef EXPERIMENTAL_SPF
3542 rc = spf_process(&arg, sender_address, SPF_PROCESS_NORMAL);
3544 case ACLC_SPF_GUESS:
3545 rc = spf_process(&arg, sender_address, SPF_PROCESS_GUESS);
3549 /* If the verb is WARN, discard any user message from verification, because
3550 such messages are SMTP responses, not header additions. The latter come
3551 only from explicit "message" modifiers. However, put the user message into
3552 $acl_verify_message so it can be used in subsequent conditions or modifiers
3553 (until something changes it). */
3556 rc = acl_verify(where, addr, arg, user_msgptr, log_msgptr, basic_errno);
3557 acl_verify_message = *user_msgptr;
3558 if (verb == ACL_WARN) *user_msgptr = NULL;
3562 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown "
3563 "condition %d", cb->type);
3567 /* If a condition was negated, invert OK/FAIL. */
3569 if (!cond_modifiers[cb->type] && cb->u.negated)
3571 if (rc == OK) rc = FAIL;
3572 else if (rc == FAIL || rc == FAIL_DROP) rc = OK;
3575 if (rc != OK) break; /* Conditions loop */
3579 /* If the result is the one for which "message" and/or "log_message" are used,
3580 handle the values of these modifiers. If there isn't a log message set, we make
3581 it the same as the user message.
3583 "message" is a user message that will be included in an SMTP response. Unless
3584 it is empty, it overrides any previously set user message.
3586 "log_message" is a non-user message, and it adds to any existing non-user
3587 message that is already set.
3589 Most verbs have but a single return for which the messages are relevant, but
3590 for "discard", it's useful to have the log message both when it succeeds and
3591 when it fails. For "accept", the message is used in the OK case if there is no
3592 "endpass", but (for backwards compatibility) in the FAIL case if "endpass" is
3595 if (*epp && rc == OK) user_message = NULL;
3597 if (((1<<rc) & msgcond[verb]) != 0)
3600 uschar *old_user_msgptr = *user_msgptr;
3601 uschar *old_log_msgptr = (*log_msgptr != NULL)? *log_msgptr : old_user_msgptr;
3603 /* If the verb is "warn", messages generated by conditions (verification or
3604 nested ACLs) are always discarded. This also happens for acceptance verbs
3605 when they actually do accept. Only messages specified at this level are used.
3606 However, the value of an existing message is available in $acl_verify_message
3607 during expansions. */
3609 if (verb == ACL_WARN ||
3610 (rc == OK && (verb == ACL_ACCEPT || verb == ACL_DISCARD)))
3611 *log_msgptr = *user_msgptr = NULL;
3613 if (user_message != NULL)
3615 acl_verify_message = old_user_msgptr;
3616 expmessage = expand_string(user_message);
3617 if (expmessage == NULL)
3619 if (!expand_string_forcedfail)
3620 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
3621 user_message, expand_string_message);
3623 else if (expmessage[0] != 0) *user_msgptr = expmessage;
3626 if (log_message != NULL)
3628 acl_verify_message = old_log_msgptr;
3629 expmessage = expand_string(log_message);
3630 if (expmessage == NULL)
3632 if (!expand_string_forcedfail)
3633 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
3634 log_message, expand_string_message);
3636 else if (expmessage[0] != 0)
3638 *log_msgptr = (*log_msgptr == NULL)? expmessage :
3639 string_sprintf("%s: %s", expmessage, *log_msgptr);
3643 /* If no log message, default it to the user message */
3645 if (*log_msgptr == NULL) *log_msgptr = *user_msgptr;
3648 acl_verify_message = NULL;
3656 /*************************************************
3657 * Get line from a literal ACL *
3658 *************************************************/
3660 /* This function is passed to acl_read() in order to extract individual lines
3661 of a literal ACL, which we access via static pointers. We can destroy the
3662 contents because this is called only once (the compiled ACL is remembered).
3664 This code is intended to treat the data in the same way as lines in the main
3665 Exim configuration file. That is:
3667 . Leading spaces are ignored.
3669 . A \ at the end of a line is a continuation - trailing spaces after the \
3670 are permitted (this is because I don't believe in making invisible things
3671 significant). Leading spaces on the continued part of a line are ignored.
3673 . Physical lines starting (significantly) with # are totally ignored, and
3674 may appear within a sequence of backslash-continued lines.
3676 . Blank lines are ignored, but will end a sequence of continuations.
3679 Returns: a pointer to the next line
3683 static uschar *acl_text; /* Current pointer in the text */
3684 static uschar *acl_text_end; /* Points one past the terminating '0' */
3692 /* This loop handles leading blank lines and comments. */
3696 while (isspace(*acl_text)) acl_text++; /* Leading spaces/empty lines */
3697 if (*acl_text == 0) return NULL; /* No more data */
3698 yield = acl_text; /* Potential data line */
3700 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3702 /* If we hit the end before a newline, we have the whole logical line. If
3703 it's a comment, there's no more data to be given. Otherwise, yield it. */
3705 if (*acl_text == 0) return (*yield == '#')? NULL : yield;
3707 /* After reaching a newline, end this loop if the physical line does not
3708 start with '#'. If it does, it's a comment, and the loop continues. */
3710 if (*yield != '#') break;
3713 /* This loop handles continuations. We know we have some real data, ending in
3714 newline. See if there is a continuation marker at the end (ignoring trailing
3715 white space). We know that *yield is not white space, so no need to test for
3716 cont > yield in the backwards scanning loop. */
3721 for (cont = acl_text - 1; isspace(*cont); cont--);
3723 /* If no continuation follows, we are done. Mark the end of the line and
3732 /* We have encountered a continuation. Skip over whitespace at the start of
3733 the next line, and indeed the whole of the next line or lines if they are
3738 while (*(++acl_text) == ' ' || *acl_text == '\t');
3739 if (*acl_text != '#') break;
3740 while (*(++acl_text) != 0 && *acl_text != '\n');
3743 /* We have the start of a continuation line. Move all the rest of the data
3744 to join onto the previous line, and then find its end. If the end is not a
3745 newline, we are done. Otherwise loop to look for another continuation. */
3747 memmove(cont, acl_text, acl_text_end - acl_text);
3748 acl_text_end -= acl_text - cont;
3750 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3751 if (*acl_text == 0) return yield;
3754 /* Control does not reach here */
3761 /*************************************************
3762 * Check access using an ACL *
3763 *************************************************/
3765 /* This function is called from address_check. It may recurse via
3766 acl_check_condition() - hence the use of a level to stop looping. The ACL is
3767 passed as a string which is expanded. A forced failure implies no access check
3768 is required. If the result is a single word, it is taken as the name of an ACL
3769 which is sought in the global ACL tree. Otherwise, it is taken as literal ACL
3770 text, complete with newlines, and parsed as such. In both cases, the ACL check
3771 is then run. This function uses an auxiliary function for acl_read() to call
3772 for reading individual lines of a literal ACL. This is acl_getline(), which
3773 appears immediately above.
3776 where where called from
3777 addr address item when called from RCPT; otherwise NULL
3778 s the input string; NULL is the same as an empty ACL => DENY
3779 level the nesting level
3780 user_msgptr where to put a user error (for SMTP response)
3781 log_msgptr where to put a logging message (not for SMTP response)
3783 Returns: OK access is granted
3784 DISCARD access is apparently granted...
3785 FAIL access is denied
3786 FAIL_DROP access is denied; drop the connection
3787 DEFER can't tell at the moment
3792 acl_check_internal(int where, address_item *addr, uschar *s, int level,
3793 uschar **user_msgptr, uschar **log_msgptr)
3796 acl_block *acl = NULL;
3797 uschar *acl_name = US"inline ACL";
3800 /* Catch configuration loops */
3804 *log_msgptr = US"ACL nested too deep: possible loop";
3810 HDEBUG(D_acl) debug_printf("ACL is NULL: implicit DENY\n");
3814 /* At top level, we expand the incoming string. At lower levels, it has already
3815 been expanded as part of condition processing. */
3819 ss = expand_string(s);
3822 if (expand_string_forcedfail) return OK;
3823 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s", s,
3824 expand_string_message);
3830 while (isspace(*ss))ss++;
3832 /* If we can't find a named ACL, the default is to parse it as an inline one.
3833 (Unless it begins with a slash; non-existent files give rise to an error.) */
3837 /* Handle the case of a string that does not contain any spaces. Look for a
3838 named ACL among those read from the configuration, or a previously read file.
3839 It is possible that the pointer to the ACL is NULL if the configuration
3840 contains a name with no data. If not found, and the text begins with '/',
3841 read an ACL from a file, and save it so it can be re-used. */
3843 if (Ustrchr(ss, ' ') == NULL)
3845 tree_node *t = tree_search(acl_anchor, ss);
3848 acl = (acl_block *)(t->data.ptr);
3851 HDEBUG(D_acl) debug_printf("ACL \"%s\" is empty: implicit DENY\n", ss);
3854 acl_name = string_sprintf("ACL \"%s\"", ss);
3855 HDEBUG(D_acl) debug_printf("using ACL \"%s\"\n", ss);
3858 else if (*ss == '/')
3860 struct stat statbuf;
3861 fd = Uopen(ss, O_RDONLY, 0);
3864 *log_msgptr = string_sprintf("failed to open ACL file \"%s\": %s", ss,
3869 if (fstat(fd, &statbuf) != 0)
3871 *log_msgptr = string_sprintf("failed to fstat ACL file \"%s\": %s", ss,
3876 acl_text = store_get(statbuf.st_size + 1);
3877 acl_text_end = acl_text + statbuf.st_size + 1;
3879 if (read(fd, acl_text, statbuf.st_size) != statbuf.st_size)
3881 *log_msgptr = string_sprintf("failed to read ACL file \"%s\": %s",
3882 ss, strerror(errno));
3885 acl_text[statbuf.st_size] = 0;
3888 acl_name = string_sprintf("ACL \"%s\"", ss);
3889 HDEBUG(D_acl) debug_printf("read ACL from file %s\n", ss);
3893 /* Parse an ACL that is still in text form. If it came from a file, remember it
3894 in the ACL tree, having read it into the POOL_PERM store pool so that it
3895 persists between multiple messages. */
3899 int old_pool = store_pool;
3900 if (fd >= 0) store_pool = POOL_PERM;
3901 acl = acl_read(acl_getline, log_msgptr);
3902 store_pool = old_pool;
3903 if (acl == NULL && *log_msgptr != NULL) return ERROR;
3906 tree_node *t = store_get_perm(sizeof(tree_node) + Ustrlen(ss));
3907 Ustrcpy(t->name, ss);
3909 (void)tree_insertnode(&acl_anchor, t);
3913 /* Now we have an ACL to use. It's possible it may be NULL. */
3918 int basic_errno = 0;
3919 BOOL endpass_seen = FALSE;
3921 *log_msgptr = *user_msgptr = NULL;
3922 acl_temp_details = FALSE;
3924 if ((where == ACL_WHERE_QUIT || where == ACL_WHERE_NOTQUIT) &&
3925 acl->verb != ACL_ACCEPT &&
3926 acl->verb != ACL_WARN)
3928 *log_msgptr = string_sprintf("\"%s\" is not allowed in a QUIT or not-QUIT ACL",
3933 HDEBUG(D_acl) debug_printf("processing \"%s\"\n", verbs[acl->verb]);
3935 /* Clear out any search error message from a previous check before testing
3938 search_error_message = NULL;
3939 cond = acl_check_condition(acl->verb, acl->condition, where, addr, level,
3940 &endpass_seen, user_msgptr, log_msgptr, &basic_errno);
3942 /* Handle special returns: DEFER causes a return except on a WARN verb;
3943 ERROR always causes a return. */
3948 HDEBUG(D_acl) debug_printf("%s: condition test deferred in %s\n", verbs[acl->verb], acl_name);
3949 if (basic_errno != ERRNO_CALLOUTDEFER)
3951 if (search_error_message != NULL && *search_error_message != 0)
3952 *log_msgptr = search_error_message;
3953 if (smtp_return_error_details) acl_temp_details = TRUE;
3957 acl_temp_details = TRUE;
3959 if (acl->verb != ACL_WARN) return DEFER;
3962 default: /* Paranoia */
3964 HDEBUG(D_acl) debug_printf("%s: condition test error in %s\n", verbs[acl->verb], acl_name);
3968 HDEBUG(D_acl) debug_printf("%s: condition test succeeded in %s\n",
3969 verbs[acl->verb], acl_name);
3973 HDEBUG(D_acl) debug_printf("%s: condition test failed in %s\n", verbs[acl->verb], acl_name);
3976 /* DISCARD and DROP can happen only from a nested ACL condition, and
3977 DISCARD can happen only for an "accept" or "discard" verb. */
3980 HDEBUG(D_acl) debug_printf("%s: condition test yielded \"discard\" in %s\n",
3981 verbs[acl->verb], acl_name);
3985 HDEBUG(D_acl) debug_printf("%s: condition test yielded \"drop\" in %s\n",
3986 verbs[acl->verb], acl_name);
3990 /* At this point, cond for most verbs is either OK or FAIL or (as a result of
3991 a nested ACL condition) FAIL_DROP. However, for WARN, cond may be DEFER, and
3992 for ACCEPT and DISCARD, it may be DISCARD after a nested ACL call. */
3997 if (cond == OK || cond == DISCARD) return cond;
4000 HDEBUG(D_acl) debug_printf("accept: endpass encountered - denying access\n");
4008 acl_temp_details = TRUE;
4014 if (cond == OK) return FAIL;
4018 if (cond == OK || cond == DISCARD) return DISCARD;
4021 HDEBUG(D_acl) debug_printf("discard: endpass encountered - denying access\n");
4027 if (cond == OK) return FAIL_DROP;
4031 if (cond != OK) return cond;
4036 acl_warn(where, *user_msgptr, *log_msgptr);
4037 else if (cond == DEFER && (log_extra_selector & LX_acl_warn_skipped) != 0)
4038 log_write(0, LOG_MAIN, "%s Warning: ACL \"warn\" statement skipped: "
4039 "condition test deferred%s%s", host_and_ident(TRUE),
4040 (*log_msgptr == NULL)? US"" : US": ",
4041 (*log_msgptr == NULL)? US"" : *log_msgptr);
4042 *log_msgptr = *user_msgptr = NULL; /* In case implicit DENY follows */
4046 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown verb %d",
4051 /* Pass to the next ACL item */
4056 /* We have reached the end of the ACL. This is an implicit DENY. */
4058 HDEBUG(D_acl) debug_printf("end of %s: implicit DENY\n", acl_name);
4065 /* Same args as acl_check_internal() above, but the string s is
4066 the name of an ACL followed optionally by up to 9 space-separated arguments.
4067 The name and args are separately expanded. Args go into $acl_arg globals. */
4069 acl_check_wargs(int where, address_item *addr, uschar *s, int level,
4070 uschar **user_msgptr, uschar **log_msgptr)
4073 uschar * tmp_arg[9]; /* must match acl_arg[] */
4074 uschar * sav_arg[9]; /* must match acl_arg[] */
4080 if (!(tmp = string_dequote(&s)) || !(name = expand_string(tmp)))
4083 for (i = 0; i < 9; i++)
4085 while (*s && isspace(*s)) s++;
4087 if (!(tmp = string_dequote(&s)) || !(tmp_arg[i] = expand_string(tmp)))
4094 sav_narg = acl_narg;
4096 for (i = 0; i < acl_narg; i++)
4098 sav_arg[i] = acl_arg[i];
4099 acl_arg[i] = tmp_arg[i];
4103 sav_arg[i] = acl_arg[i];
4104 acl_arg[i++] = NULL;
4107 ret = acl_check_internal(where, addr, name, level, user_msgptr, log_msgptr);
4109 acl_narg = sav_narg;
4110 for (i = 0; i < 9; i++) acl_arg[i] = sav_arg[i];
4114 if (expand_string_forcedfail) return ERROR;
4115 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s",
4116 tmp, expand_string_message);
4117 return search_find_defer?DEFER:ERROR;
4122 /*************************************************
4123 * Check access using an ACL *
4124 *************************************************/
4126 /* Alternate interface for ACL, used by expansions */
4128 acl_eval(int where, uschar *s, uschar **user_msgptr, uschar **log_msgptr)
4131 address_item *addr = NULL;
4133 *user_msgptr = *log_msgptr = NULL;
4134 sender_verified_failed = NULL;
4135 ratelimiters_cmd = NULL;
4136 log_reject_target = LOG_MAIN|LOG_REJECT;
4138 if (where == ACL_WHERE_RCPT)
4140 adb = address_defaults;
4142 addr->address = expand_string(US"$local_part@$domain");
4143 addr->domain = deliver_domain;
4144 addr->local_part = deliver_localpart;
4145 addr->cc_local_part = deliver_localpart;
4146 addr->lc_local_part = deliver_localpart;
4149 return acl_check_internal(where, addr, s, 0, user_msgptr, log_msgptr);
4154 /* This is the external interface for ACL checks. It sets up an address and the
4155 expansions for $domain and $local_part when called after RCPT, then calls
4156 acl_check_internal() to do the actual work.
4159 where ACL_WHERE_xxxx indicating where called from
4160 recipient RCPT address for RCPT check, else NULL
4161 s the input string; NULL is the same as an empty ACL => DENY
4162 user_msgptr where to put a user error (for SMTP response)
4163 log_msgptr where to put a logging message (not for SMTP response)
4165 Returns: OK access is granted by an ACCEPT verb
4166 DISCARD access is granted by a DISCARD verb
4167 FAIL access is denied
4168 FAIL_DROP access is denied; drop the connection
4169 DEFER can't tell at the moment
4172 int acl_where = ACL_WHERE_UNKNOWN;
4175 acl_check(int where, uschar *recipient, uschar *s, uschar **user_msgptr,
4176 uschar **log_msgptr)
4180 address_item *addr = NULL;
4182 *user_msgptr = *log_msgptr = NULL;
4183 sender_verified_failed = NULL;
4184 ratelimiters_cmd = NULL;
4185 log_reject_target = LOG_MAIN|LOG_REJECT;
4187 #ifdef EXPERIMENTAL_PRDR
4188 if (where == ACL_WHERE_RCPT || where == ACL_WHERE_PRDR )
4190 if (where == ACL_WHERE_RCPT )
4193 adb = address_defaults;
4195 addr->address = recipient;
4196 if (deliver_split_address(addr) == DEFER)
4198 *log_msgptr = US"defer in percent_hack_domains check";
4201 deliver_domain = addr->domain;
4202 deliver_localpart = addr->local_part;
4206 rc = acl_check_internal(where, addr, s, 0, user_msgptr, log_msgptr);
4207 acl_where = ACL_WHERE_UNKNOWN;
4209 /* Cutthrough - if requested,
4210 and WHERE_RCPT and not yet opened conn as result of recipient-verify,
4211 and rcpt acl returned accept,
4212 and first recipient (cancel on any subsequents)
4213 open one now and run it up to RCPT acceptance.
4214 A failed verify should cancel cutthrough request.
4216 Initial implementation: dual-write to spool.
4217 Assume the rxd datastream is now being copied byte-for-byte to an open cutthrough connection.
4219 Cease cutthrough copy on rxd final dot; do not send one.
4221 On a data acl, if not accept and a cutthrough conn is open, hard-close it (no SMTP niceness).
4223 On data acl accept, terminate the dataphase on an open cutthrough conn. If accepted or
4224 perm-rejected, reflect that to the original sender - and dump the spooled copy.
4225 If temp-reject, close the conn (and keep the spooled copy).
4226 If conn-failure, no action (and keep the spooled copy).
4230 case ACL_WHERE_RCPT:
4231 #ifdef EXPERIMENTAL_PRDR
4232 case ACL_WHERE_PRDR:
4234 if( rcpt_count > 1 )
4235 cancel_cutthrough_connection("more than one recipient");
4236 else if (rc == OK && cutthrough_delivery && cutthrough_fd < 0)
4237 open_cutthrough_connection(addr);
4240 case ACL_WHERE_PREDATA:
4242 cutthrough_predata();
4244 cancel_cutthrough_connection("predata acl not ok");
4247 case ACL_WHERE_QUIT:
4248 case ACL_WHERE_NOTQUIT:
4249 cancel_cutthrough_connection("quit or notquit");
4256 deliver_domain = deliver_localpart = deliver_address_data =
4257 sender_address_data = NULL;
4259 /* A DISCARD response is permitted only for message ACLs, excluding the PREDATA
4260 ACL, which is really in the middle of an SMTP command. */
4264 if (where > ACL_WHERE_NOTSMTP || where == ACL_WHERE_PREDATA)
4266 log_write(0, LOG_MAIN|LOG_PANIC, "\"discard\" verb not allowed in %s "
4267 "ACL", acl_wherenames[where]);
4273 /* A DROP response is not permitted from MAILAUTH */
4275 if (rc == FAIL_DROP && where == ACL_WHERE_MAILAUTH)
4277 log_write(0, LOG_MAIN|LOG_PANIC, "\"drop\" verb not allowed in %s "
4278 "ACL", acl_wherenames[where]);
4282 /* Before giving a response, take a look at the length of any user message, and
4283 split it up into multiple lines if possible. */
4285 *user_msgptr = string_split_message(*user_msgptr);
4286 if (fake_response != OK)
4287 fake_response_text = string_split_message(fake_response_text);
4293 /*************************************************
4294 * Create ACL variable *
4295 *************************************************/
4297 /* Create an ACL variable or reuse an existing one. ACL variables are in a
4298 binary tree (see tree.c) with acl_var_c and acl_var_m as root nodes.
4301 name pointer to the variable's name, starting with c or m
4303 Returns the pointer to variable's tree node
4307 acl_var_create(uschar *name)
4309 tree_node *node, **root;
4310 root = (name[0] == 'c')? &acl_var_c : &acl_var_m;
4311 node = tree_search(*root, name);
4314 node = store_get(sizeof(tree_node) + Ustrlen(name));
4315 Ustrcpy(node->name, name);
4316 (void)tree_insertnode(root, node);
4318 node->data.ptr = NULL;
4324 /*************************************************
4325 * Write an ACL variable in spool format *
4326 *************************************************/
4328 /* This function is used as a callback for tree_walk when writing variables to
4329 the spool file. To retain spool file compatibility, what is written is -aclc or
4330 -aclm followed by the rest of the name and the data length, space separated,
4331 then the value itself, starting on a new line, and terminated by an additional
4332 newline. When we had only numbered ACL variables, the first line might look
4333 like this: "-aclc 5 20". Now it might be "-aclc foo 20" for the variable called
4337 name of the variable
4338 value of the variable
4339 ctx FILE pointer (as a void pointer)
4345 acl_var_write(uschar *name, uschar *value, void *ctx)
4347 FILE *f = (FILE *)ctx;
4348 fprintf(f, "-acl%c %s %d\n%s\n", name[0], name+1, Ustrlen(value), value);