1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2016 */
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
72 #ifdef EXPERIMENTAL_DMARC
82 ACLC_LOG_REJECT_TARGET,
84 #ifdef WITH_CONTENT_SCAN
88 #ifdef WITH_CONTENT_SCAN
94 #ifdef WITH_CONTENT_SCAN
101 #ifdef WITH_CONTENT_SCAN
104 #ifdef EXPERIMENTAL_SPF
111 /* ACL conditions/modifiers: "delay", "control", "continue", "endpass",
112 "message", "log_message", "log_reject_target", "logwrite", "queue" and "set" are
113 modifiers that look like conditions but always return TRUE. They are used for
114 their side effects. */
116 static uschar *conditions[] = {
120 #ifdef EXPERIMENTAL_BRIGHTMAIL
126 #ifdef EXPERIMENTAL_DCC
129 #ifdef WITH_CONTENT_SCAN
137 #ifdef EXPERIMENTAL_DMARC
147 US"log_reject_target",
149 #ifdef WITH_CONTENT_SCAN
153 #ifdef WITH_CONTENT_SCAN
159 #ifdef WITH_CONTENT_SCAN
166 #ifdef WITH_CONTENT_SCAN
169 #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,
210 CONTROL_UTF8_DOWNCONVERT,
212 CONTROL_NO_MULTILINE,
213 CONTROL_NO_PIPELINING,
214 CONTROL_NO_DELAY_FLUSH,
215 CONTROL_NO_CALLOUT_FLUSH
218 /* ACL control names; keep in step with the table above! This list is used for
219 turning ids into names. The actual list of recognized names is in the variable
220 control_def controls_list[] below. The fact that there are two lists is a mess
221 and should be tidied up. */
223 static uschar *controls[] = {
224 US"allow_auth_unadvertised",
225 #ifdef EXPERIMENTAL_BRIGHTMAIL
230 US"dkim_disable_verify",
232 #ifdef EXPERIMENTAL_DMARC
233 US"dmarc_disable_verify",
234 US"dmarc_enable_forensic",
238 US"caseful_local_part",
239 US"caselower_local_part",
240 US"cutthrough_delivery",
246 US"suppress_local_fixups",
247 #ifdef WITH_CONTENT_SCAN
253 US"utf8_downconvert",
255 US"no_multiline_responses",
261 /* Flags to indicate for which conditions/modifiers a string expansion is done
262 at the outer level. In the other cases, expansion already occurs in the
263 checking functions. */
265 static uschar cond_expand_at_top[] = {
267 TRUE, /* add_header */
268 FALSE, /* authenticated */
269 #ifdef EXPERIMENTAL_BRIGHTMAIL
270 TRUE, /* bmi_optin */
272 TRUE, /* condition */
275 #ifdef EXPERIMENTAL_DCC
278 #ifdef WITH_CONTENT_SCAN
283 TRUE, /* dkim_signers */
284 TRUE, /* dkim_status */
286 #ifdef EXPERIMENTAL_DMARC
287 TRUE, /* dmarc_status */
291 FALSE, /* encrypted */
294 FALSE, /* local_parts */
295 TRUE, /* log_message */
296 TRUE, /* log_reject_target */
298 #ifdef WITH_CONTENT_SCAN
302 #ifdef WITH_CONTENT_SCAN
303 TRUE, /* mime_regex */
306 TRUE, /* ratelimit */
307 FALSE, /* recipients */
308 #ifdef WITH_CONTENT_SCAN
311 TRUE, /* remove_header */
312 FALSE, /* sender_domains */
315 #ifdef WITH_CONTENT_SCAN
318 #ifdef EXPERIMENTAL_SPF
320 TRUE, /* spf_guess */
326 /* Flags to identify the modifiers */
328 static uschar cond_modifiers[] = {
330 TRUE, /* add_header */
331 FALSE, /* authenticated */
332 #ifdef EXPERIMENTAL_BRIGHTMAIL
333 TRUE, /* bmi_optin */
335 FALSE, /* condition */
338 #ifdef EXPERIMENTAL_DCC
341 #ifdef WITH_CONTENT_SCAN
346 FALSE, /* dkim_signers */
347 FALSE, /* dkim_status */
349 #ifdef EXPERIMENTAL_DMARC
350 FALSE, /* dmarc_status */
352 FALSE, /* dnslists */
354 FALSE, /* encrypted */
357 FALSE, /* local_parts */
358 TRUE, /* log_message */
359 TRUE, /* log_reject_target */
361 #ifdef WITH_CONTENT_SCAN
365 #ifdef WITH_CONTENT_SCAN
366 FALSE, /* mime_regex */
369 FALSE, /* ratelimit */
370 FALSE, /* recipients */
371 #ifdef WITH_CONTENT_SCAN
374 TRUE, /* remove_header */
375 FALSE, /* sender_domains */
378 #ifdef WITH_CONTENT_SCAN
381 #ifdef EXPERIMENTAL_SPF
383 FALSE, /* spf_guess */
389 /* Bit map vector of which conditions and modifiers are not allowed at certain
390 times. For each condition and modifier, there's a bitmap of dis-allowed times.
391 For some, it is easier to specify the negation of a small number of allowed
394 static unsigned int cond_forbids[] = {
398 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* add_header */
399 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
403 (1<<ACL_WHERE_MIME)|(1<<ACL_WHERE_NOTSMTP)|
405 (1<<ACL_WHERE_NOTSMTP_START)),
407 (1<<ACL_WHERE_NOTSMTP)| /* authenticated */
408 (1<<ACL_WHERE_NOTSMTP_START)|
409 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO),
411 #ifdef EXPERIMENTAL_BRIGHTMAIL
412 (1<<ACL_WHERE_AUTH)| /* bmi_optin */
413 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
414 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_MIME)|
418 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
419 (1<<ACL_WHERE_MAILAUTH)|
420 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
421 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_PREDATA)|
422 (1<<ACL_WHERE_NOTSMTP_START),
429 /* Certain types of control are always allowed, so we let it through
430 always and check in the control processing itself. */
434 #ifdef EXPERIMENTAL_DCC
436 ~((1<<ACL_WHERE_DATA)| /* dcc */
440 (1<<ACL_WHERE_NOTSMTP)),
443 #ifdef WITH_CONTENT_SCAN
445 ~(1<<ACL_WHERE_MIME), /* decode */
448 (1<<ACL_WHERE_NOTQUIT), /* delay */
452 ~(1<<ACL_WHERE_DKIM), /* dkim_signers */
455 ~(1<<ACL_WHERE_DKIM), /* dkim_status */
458 #ifdef EXPERIMENTAL_DMARC
460 ~(1<<ACL_WHERE_DATA), /* dmarc_status */
463 /* Explicit key lookups can be made in non-smtp ACLs so pass
464 always and check in the verify processing itself. */
469 ~((1<<ACL_WHERE_RCPT) /* domains */
476 (1<<ACL_WHERE_NOTSMTP)| /* encrypted */
477 (1<<ACL_WHERE_CONNECT)|
478 (1<<ACL_WHERE_NOTSMTP_START)|
483 (1<<ACL_WHERE_NOTSMTP)| /* hosts */
484 (1<<ACL_WHERE_NOTSMTP_START),
487 ~((1<<ACL_WHERE_RCPT) /* local_parts */
496 0, /* log_reject_target */
500 #ifdef WITH_CONTENT_SCAN
502 ~((1<<ACL_WHERE_DATA)| /* malware */
506 (1<<ACL_WHERE_NOTSMTP)),
511 #ifdef WITH_CONTENT_SCAN
513 ~(1<<ACL_WHERE_MIME), /* mime_regex */
520 ~(1<<ACL_WHERE_RCPT), /* recipients */
522 #ifdef WITH_CONTENT_SCAN
524 ~((1<<ACL_WHERE_DATA)| /* regex */
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)|
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 */
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),
584 /* Certain types of verify are always allowed, so we let it through
585 always and check in the verify function itself */
591 /* Bit map vector of which controls are not allowed at certain times. For
592 each control, there's a bitmap of dis-allowed times. For some, it is easier to
593 specify the negation of a small number of allowed times. */
595 static unsigned int control_forbids[] = {
597 ~((1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)), /* allow_auth_unadvertised */
599 #ifdef EXPERIMENTAL_BRIGHTMAIL
606 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* dkim_disable_verify */
607 # ifndef DISABLE_PRDR
610 (1<<ACL_WHERE_NOTSMTP_START),
613 #ifdef EXPERIMENTAL_DMARC
614 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* dmarc_disable_verify */
615 (1<<ACL_WHERE_NOTSMTP_START),
616 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* dmarc_enable_forensic */
617 (1<<ACL_WHERE_NOTSMTP_START),
620 (1<<ACL_WHERE_NOTSMTP)|
621 (1<<ACL_WHERE_NOTSMTP_START)|
622 (1<<ACL_WHERE_NOTQUIT), /* dscp */
627 ~(1<<ACL_WHERE_RCPT), /* caseful_local_part */
630 ~(1<<ACL_WHERE_RCPT), /* caselower_local_part */
633 0, /* cutthrough_delivery */
635 (1<<ACL_WHERE_NOTSMTP)| /* enforce_sync */
636 (1<<ACL_WHERE_NOTSMTP_START),
638 (1<<ACL_WHERE_NOTSMTP)| /* no_enforce_sync */
639 (1<<ACL_WHERE_NOTSMTP_START),
642 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* freeze */
643 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
644 // (1<<ACL_WHERE_PRDR)| /* Not allow one user to freeze for all */
645 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)),
648 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* queue_only */
649 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
650 // (1<<ACL_WHERE_PRDR)| /* Not allow one user to freeze for all */
651 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)),
654 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* submission */
655 (1<<ACL_WHERE_PREDATA)),
658 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* suppress_local_fixups */
659 (1<<ACL_WHERE_PREDATA)|
660 (1<<ACL_WHERE_NOTSMTP_START)),
662 #ifdef WITH_CONTENT_SCAN
664 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* no_mbox_unspool */
665 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
666 // (1<<ACL_WHERE_PRDR)| /* Not allow one user to freeze for all */
667 (1<<ACL_WHERE_MIME)),
671 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakedefer */
672 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
676 (1<<ACL_WHERE_MIME)),
679 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakereject */
680 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
684 (1<<ACL_WHERE_MIME)),
687 0, /* utf8_downconvert */
690 (1<<ACL_WHERE_NOTSMTP)| /* no_multiline */
691 (1<<ACL_WHERE_NOTSMTP_START),
693 (1<<ACL_WHERE_NOTSMTP)| /* no_pipelining */
694 (1<<ACL_WHERE_NOTSMTP_START),
696 (1<<ACL_WHERE_NOTSMTP)| /* no_delay_flush */
697 (1<<ACL_WHERE_NOTSMTP_START),
699 (1<<ACL_WHERE_NOTSMTP)| /* no_callout_flush */
700 (1<<ACL_WHERE_NOTSMTP_START)
703 /* Structure listing various control arguments, with their characteristics. */
705 typedef struct control_def {
707 int value; /* CONTROL_xxx value */
708 BOOL has_option; /* Has /option(s) following */
711 static control_def controls_list[] = {
712 { US"allow_auth_unadvertised", CONTROL_AUTH_UNADVERTISED, FALSE },
713 #ifdef EXPERIMENTAL_BRIGHTMAIL
714 { US"bmi_run", CONTROL_BMI_RUN, FALSE },
716 { US"debug", CONTROL_DEBUG, TRUE },
718 { US"dkim_disable_verify", CONTROL_DKIM_VERIFY, FALSE },
720 #ifdef EXPERIMENTAL_DMARC
721 { US"dmarc_disable_verify", CONTROL_DMARC_VERIFY, FALSE },
722 { US"dmarc_enable_forensic", CONTROL_DMARC_FORENSIC, FALSE },
724 { US"dscp", CONTROL_DSCP, TRUE },
725 { US"caseful_local_part", CONTROL_CASEFUL_LOCAL_PART, FALSE },
726 { US"caselower_local_part", CONTROL_CASELOWER_LOCAL_PART, FALSE },
727 { US"enforce_sync", CONTROL_ENFORCE_SYNC, FALSE },
728 { US"freeze", CONTROL_FREEZE, TRUE },
729 { US"no_callout_flush", CONTROL_NO_CALLOUT_FLUSH, FALSE },
730 { US"no_delay_flush", CONTROL_NO_DELAY_FLUSH, FALSE },
731 { US"no_enforce_sync", CONTROL_NO_ENFORCE_SYNC, FALSE },
732 { US"no_multiline_responses", CONTROL_NO_MULTILINE, FALSE },
733 { US"no_pipelining", CONTROL_NO_PIPELINING, FALSE },
734 { US"queue_only", CONTROL_QUEUE_ONLY, FALSE },
735 #ifdef WITH_CONTENT_SCAN
736 { US"no_mbox_unspool", CONTROL_NO_MBOX_UNSPOOL, FALSE },
738 { US"fakedefer", CONTROL_FAKEDEFER, TRUE },
739 { US"fakereject", CONTROL_FAKEREJECT, TRUE },
740 { US"submission", CONTROL_SUBMISSION, TRUE },
741 { US"suppress_local_fixups", CONTROL_SUPPRESS_LOCAL_FIXUPS, FALSE },
742 { US"cutthrough_delivery", CONTROL_CUTTHROUGH_DELIVERY, FALSE },
744 { US"utf8_downconvert", CONTROL_UTF8_DOWNCONVERT, TRUE }
748 /* Support data structures for Client SMTP Authorization. acl_verify_csa()
749 caches its result in a tree to avoid repeated DNS queries. The result is an
750 integer code which is used as an index into the following tables of
751 explanatory strings and verification return codes. */
753 static tree_node *csa_cache = NULL;
755 enum { CSA_UNKNOWN, CSA_OK, CSA_DEFER_SRV, CSA_DEFER_ADDR,
756 CSA_FAIL_EXPLICIT, CSA_FAIL_DOMAIN, CSA_FAIL_NOADDR, CSA_FAIL_MISMATCH };
758 /* The acl_verify_csa() return code is translated into an acl_verify() return
759 code using the following table. It is OK unless the client is definitely not
760 authorized. This is because CSA is supposed to be optional for sending sites,
761 so recipients should not be too strict about checking it - especially because
762 DNS problems are quite likely to occur. It's possible to use $csa_status in
763 further ACL conditions to distinguish ok, unknown, and defer if required, but
764 the aim is to make the usual configuration simple. */
766 static int csa_return_code[] = {
768 FAIL, FAIL, FAIL, FAIL
771 static uschar *csa_status_string[] = {
772 US"unknown", US"ok", US"defer", US"defer",
773 US"fail", US"fail", US"fail", US"fail"
776 static uschar *csa_reason_string[] = {
779 US"deferred (SRV lookup failed)",
780 US"deferred (target address lookup failed)",
781 US"failed (explicit authorization required)",
782 US"failed (host name not authorized)",
783 US"failed (no authorized addresses)",
784 US"failed (client address mismatch)"
787 /* Options for the ratelimit condition. Note that there are two variants of
788 the per_rcpt option, depending on the ACL that is used to measure the rate.
789 However any ACL must be able to look up per_rcpt rates in /noupdate mode,
790 so the two variants must have the same internal representation as well as
791 the same configuration string. */
794 RATE_PER_WHAT, RATE_PER_CLASH, RATE_PER_ADDR, RATE_PER_BYTE, RATE_PER_CMD,
795 RATE_PER_CONN, RATE_PER_MAIL, RATE_PER_RCPT, RATE_PER_ALLRCPTS
798 #define RATE_SET(var,new) \
799 (((var) == RATE_PER_WHAT) ? ((var) = RATE_##new) : ((var) = RATE_PER_CLASH))
801 static uschar *ratelimit_option_string[] = {
802 US"?", US"!", US"per_addr", US"per_byte", US"per_cmd",
803 US"per_conn", US"per_mail", US"per_rcpt", US"per_rcpt"
806 /* Enable recursion between acl_check_internal() and acl_check_condition() */
808 static int acl_check_wargs(int, address_item *, const uschar *, int, uschar **,
812 /*************************************************
813 * Pick out name from list *
814 *************************************************/
816 /* Use a binary chop method
823 Returns: offset in list, or -1 if not found
827 acl_checkname(uschar *name, uschar **list, int end)
833 int mid = (start + end)/2;
834 int c = Ustrcmp(name, list[mid]);
835 if (c == 0) return mid;
836 if (c < 0) end = mid; else start = mid + 1;
843 /*************************************************
844 * Read and parse one ACL *
845 *************************************************/
847 /* This function is called both from readconf in order to parse the ACLs in the
848 configuration file, and also when an ACL is encountered dynamically (e.g. as
849 the result of an expansion). It is given a function to call in order to
850 retrieve the lines of the ACL. This function handles skipping comments and
851 blank lines (where relevant).
854 func function to get next line of ACL
855 error where to put an error message
857 Returns: pointer to ACL, or NULL
858 NULL can be legal (empty ACL); in this case error will be NULL
862 acl_read(uschar *(*func)(void), uschar **error)
864 acl_block *yield = NULL;
865 acl_block **lastp = &yield;
866 acl_block *this = NULL;
867 acl_condition_block *cond;
868 acl_condition_block **condp = NULL;
873 while ((s = (*func)()) != NULL)
876 BOOL negated = FALSE;
877 uschar *saveline = s;
880 /* Conditions (but not verbs) are allowed to be negated by an initial
883 while (isspace(*s)) s++;
890 /* Read the name of a verb or a condition, or the start of a new ACL, which
891 can be started by a name, or by a macro definition. */
893 s = readconf_readname(name, sizeof(name), s);
894 if (*s == ':' || (isupper(name[0]) && *s == '=')) return yield;
896 /* If a verb is unrecognized, it may be another condition or modifier that
897 continues the previous verb. */
899 v = acl_checkname(name, verbs, sizeof(verbs)/sizeof(char *));
904 *error = string_sprintf("unknown ACL verb \"%s\" in \"%s\"", name,
916 *error = string_sprintf("malformed ACL line \"%s\"", saveline);
919 this = store_get(sizeof(acl_block));
921 lastp = &(this->next);
924 this->condition = NULL;
925 condp = &(this->condition);
926 if (*s == 0) continue; /* No condition on this line */
932 s = readconf_readname(name, sizeof(name), s); /* Condition name */
935 /* Handle a condition or modifier. */
937 c = acl_checkname(name, conditions, sizeof(conditions)/sizeof(char *));
940 *error = string_sprintf("unknown ACL condition/modifier in \"%s\"",
945 /* The modifiers may not be negated */
947 if (negated && cond_modifiers[c])
949 *error = string_sprintf("ACL error: negation is not allowed with "
950 "\"%s\"", conditions[c]);
954 /* ENDPASS may occur only with ACCEPT or DISCARD. */
956 if (c == ACLC_ENDPASS &&
957 this->verb != ACL_ACCEPT &&
958 this->verb != ACL_DISCARD)
960 *error = string_sprintf("ACL error: \"%s\" is not allowed with \"%s\"",
961 conditions[c], verbs[this->verb]);
965 cond = store_get(sizeof(acl_condition_block));
968 cond->u.negated = negated;
971 condp = &(cond->next);
973 /* The "set" modifier is different in that its argument is "name=value"
974 rather than just a value, and we can check the validity of the name, which
975 gives us a variable name to insert into the data block. The original ACL
976 variable names were acl_c0 ... acl_c9 and acl_m0 ... acl_m9. This was
977 extended to 20 of each type, but after that people successfully argued for
978 arbitrary names. In the new scheme, the names must start with acl_c or acl_m.
979 After that, we allow alphanumerics and underscores, but the first character
980 after c or m must be a digit or an underscore. This retains backwards
987 if (Ustrncmp(s, "acl_c", 5) != 0 &&
988 Ustrncmp(s, "acl_m", 5) != 0)
990 *error = string_sprintf("invalid variable name after \"set\" in ACL "
991 "modifier \"set %s\" (must start \"acl_c\" or \"acl_m\")", s);
996 if (!isdigit(*endptr) && *endptr != '_')
998 *error = string_sprintf("invalid variable name after \"set\" in ACL "
999 "modifier \"set %s\" (digit or underscore must follow acl_c or acl_m)",
1004 while (*endptr != 0 && *endptr != '=' && !isspace(*endptr))
1006 if (!isalnum(*endptr) && *endptr != '_')
1008 *error = string_sprintf("invalid character \"%c\" in variable name "
1009 "in ACL modifier \"set %s\"", *endptr, s);
1015 cond->u.varname = string_copyn(s + 4, endptr - s - 4);
1017 while (isspace(*s)) s++;
1020 /* For "set", we are now positioned for the data. For the others, only
1021 "endpass" has no data */
1023 if (c != ACLC_ENDPASS)
1027 *error = string_sprintf("\"=\" missing after ACL \"%s\" %s", name,
1028 cond_modifiers[c]? US"modifier" : US"condition");
1031 while (isspace(*s)) s++;
1032 cond->arg = string_copy(s);
1041 /*************************************************
1042 * Set up added header line(s) *
1043 *************************************************/
1045 /* This function is called by the add_header modifier, and also from acl_warn()
1046 to implement the now-deprecated way of adding header lines using "message" on a
1047 "warn" verb. The argument is treated as a sequence of header lines which are
1048 added to a chain, provided there isn't an identical one already there.
1050 Argument: string of header lines
1055 setup_header(const uschar *hstring)
1057 const uschar *p, *q;
1058 int hlen = Ustrlen(hstring);
1060 /* Ignore any leading newlines */
1061 while (*hstring == '\n') hstring++, hlen--;
1063 /* An empty string does nothing; ensure exactly one final newline. */
1064 if (hlen <= 0) return;
1065 if (hstring[--hlen] != '\n') /* no newline */
1066 q = string_sprintf("%s\n", hstring);
1067 else if (hstring[hlen-1] == '\n') /* double newline */
1069 uschar * s = string_copy(hstring);
1070 while(s[--hlen] == '\n')
1077 /* Loop for multiple header lines, taking care about continuations */
1079 for (p = q; *p != 0; )
1083 int newtype = htype_add_bot;
1084 header_line **hptr = &acl_added_headers;
1086 /* Find next header line within the string */
1090 q = Ustrchr(q, '\n'); /* we know there was a newline */
1091 if (*(++q) != ' ' && *q != '\t') break;
1094 /* If the line starts with a colon, interpret the instruction for where to
1095 add it. This temporarily sets up a new type. */
1099 if (strncmpic(p, US":after_received:", 16) == 0)
1101 newtype = htype_add_rec;
1104 else if (strncmpic(p, US":at_start_rfc:", 14) == 0)
1106 newtype = htype_add_rfc;
1109 else if (strncmpic(p, US":at_start:", 10) == 0)
1111 newtype = htype_add_top;
1114 else if (strncmpic(p, US":at_end:", 8) == 0)
1116 newtype = htype_add_bot;
1119 while (*p == ' ' || *p == '\t') p++;
1122 /* See if this line starts with a header name, and if not, add X-ACL-Warn:
1123 to the front of it. */
1125 for (s = p; s < q - 1; s++)
1127 if (*s == ':' || !isgraph(*s)) break;
1130 hdr = string_sprintf("%s%.*s", (*s == ':')? "" : "X-ACL-Warn: ", (int) (q - p), p);
1131 hlen = Ustrlen(hdr);
1133 /* See if this line has already been added */
1135 while (*hptr != NULL)
1137 if (Ustrncmp((*hptr)->text, hdr, hlen) == 0) break;
1138 hptr = &((*hptr)->next);
1141 /* Add if not previously present */
1145 header_line *h = store_get(sizeof(header_line));
1154 /* Advance for next header line within the string */
1162 /*************************************************
1163 * List the added header lines *
1164 *************************************************/
1168 uschar * ret = NULL;
1171 header_line * h = acl_added_headers;
1175 if (!h) return NULL;
1180 while ((cp = Ustrchr(s, '\n')) != NULL)
1182 if (cp[1] == '\0') break;
1184 /* contains embedded newline; needs doubling */
1185 ret = string_catn(ret, &size, &ptr, s, cp-s+1);
1186 ret = string_catn(ret, &size, &ptr, US"\n", 1);
1189 /* last bit of header */
1191 ret = string_catn(ret, &size, &ptr, s, cp-s+1); /* newline-sep list */
1193 while((h = h->next));
1195 ret[ptr-1] = '\0'; /* overwrite last newline */
1200 /*************************************************
1201 * Set up removed header line(s) *
1202 *************************************************/
1204 /* This function is called by the remove_header modifier. The argument is
1205 treated as a sequence of header names which are added to a colon separated
1206 list, provided there isn't an identical one already there.
1208 Argument: string of header names
1213 setup_remove_header(const uschar *hnames)
1216 acl_removed_headers = acl_removed_headers
1217 ? string_sprintf("%s : %s", acl_removed_headers, hnames)
1218 : string_copy(hnames);
1223 /*************************************************
1225 *************************************************/
1227 /* This function is called when a WARN verb's conditions are true. It adds to
1228 the message's headers, and/or writes information to the log. In each case, this
1229 only happens once (per message for headers, per connection for log).
1231 ** NOTE: The header adding action using the "message" setting is historic, and
1232 its use is now deprecated. The new add_header modifier should be used instead.
1235 where ACL_WHERE_xxxx indicating which ACL this is
1236 user_message message for adding to headers
1237 log_message message for logging, if different
1243 acl_warn(int where, uschar *user_message, uschar *log_message)
1245 if (log_message != NULL && log_message != user_message)
1248 string_item *logged;
1250 text = string_sprintf("%s Warning: %s", host_and_ident(TRUE),
1251 string_printing(log_message));
1253 /* If a sender verification has failed, and the log message is "sender verify
1254 failed", add the failure message. */
1256 if (sender_verified_failed != NULL &&
1257 sender_verified_failed->message != NULL &&
1258 strcmpic(log_message, US"sender verify failed") == 0)
1259 text = string_sprintf("%s: %s", text, sender_verified_failed->message);
1261 /* Search previously logged warnings. They are kept in malloc
1262 store so they can be freed at the start of a new message. */
1264 for (logged = acl_warn_logged; logged != NULL; logged = logged->next)
1265 if (Ustrcmp(logged->text, text) == 0) break;
1269 int length = Ustrlen(text) + 1;
1270 log_write(0, LOG_MAIN, "%s", text);
1271 logged = store_malloc(sizeof(string_item) + length);
1272 logged->text = (uschar *)logged + sizeof(string_item);
1273 memcpy(logged->text, text, length);
1274 logged->next = acl_warn_logged;
1275 acl_warn_logged = logged;
1279 /* If there's no user message, we are done. */
1281 if (user_message == NULL) return;
1283 /* If this isn't a message ACL, we can't do anything with a user message.
1286 if (where > ACL_WHERE_NOTSMTP)
1288 log_write(0, LOG_MAIN|LOG_PANIC, "ACL \"warn\" with \"message\" setting "
1289 "found in a non-message (%s) ACL: cannot specify header lines here: "
1290 "message ignored", acl_wherenames[where]);
1294 /* The code for setting up header lines is now abstracted into a separate
1295 function so that it can be used for the add_header modifier as well. */
1297 setup_header(user_message);
1302 /*************************************************
1303 * Verify and check reverse DNS *
1304 *************************************************/
1306 /* Called from acl_verify() below. We look up the host name(s) of the client IP
1307 address if this has not yet been done. The host_name_lookup() function checks
1308 that one of these names resolves to an address list that contains the client IP
1309 address, so we don't actually have to do the check here.
1312 user_msgptr pointer for user message
1313 log_msgptr pointer for log message
1315 Returns: OK verification condition succeeded
1316 FAIL verification failed
1317 DEFER there was a problem verifying
1321 acl_verify_reverse(uschar **user_msgptr, uschar **log_msgptr)
1325 user_msgptr = user_msgptr; /* stop compiler warning */
1327 /* Previous success */
1329 if (sender_host_name != NULL) return OK;
1331 /* Previous failure */
1333 if (host_lookup_failed)
1335 *log_msgptr = string_sprintf("host lookup failed%s", host_lookup_msg);
1339 /* Need to do a lookup */
1342 debug_printf("looking up host name to force name/address consistency check\n");
1344 if ((rc = host_name_lookup()) != OK)
1346 *log_msgptr = (rc == DEFER)?
1347 US"host lookup deferred for reverse lookup check"
1349 string_sprintf("host lookup failed for reverse lookup check%s",
1351 return rc; /* DEFER or FAIL */
1354 host_build_sender_fullhost();
1360 /*************************************************
1361 * Check client IP address matches CSA target *
1362 *************************************************/
1364 /* Called from acl_verify_csa() below. This routine scans a section of a DNS
1365 response for address records belonging to the CSA target hostname. The section
1366 is specified by the reset argument, either RESET_ADDITIONAL or RESET_ANSWERS.
1367 If one of the addresses matches the client's IP address, then the client is
1368 authorized by CSA. If there are target IP addresses but none of them match
1369 then the client is using an unauthorized IP address. If there are no target IP
1370 addresses then the client cannot be using an authorized IP address. (This is
1371 an odd configuration - why didn't the SRV record have a weight of 1 instead?)
1374 dnsa the DNS answer block
1375 dnss a DNS scan block for us to use
1376 reset option specifing what portion to scan, as described above
1377 target the target hostname to use for matching RR names
1379 Returns: CSA_OK successfully authorized
1380 CSA_FAIL_MISMATCH addresses found but none matched
1381 CSA_FAIL_NOADDR no target addresses found
1385 acl_verify_csa_address(dns_answer *dnsa, dns_scan *dnss, int reset,
1391 BOOL target_found = FALSE;
1393 for (rr = dns_next_rr(dnsa, dnss, reset);
1395 rr = dns_next_rr(dnsa, dnss, RESET_NEXT))
1397 /* Check this is an address RR for the target hostname. */
1401 && rr->type != T_AAAA
1405 if (strcmpic(target, rr->name) != 0) continue;
1407 target_found = TRUE;
1409 /* Turn the target address RR into a list of textual IP addresses and scan
1410 the list. There may be more than one if it is an A6 RR. */
1412 for (da = dns_address_from_rr(dnsa, rr); da != NULL; da = da->next)
1414 /* If the client IP address matches the target IP address, it's good! */
1416 DEBUG(D_acl) debug_printf("CSA target address is %s\n", da->address);
1418 if (strcmpic(sender_host_address, da->address) == 0) return CSA_OK;
1422 /* If we found some target addresses but none of them matched, the client is
1423 using an unauthorized IP address, otherwise the target has no authorized IP
1426 if (target_found) return CSA_FAIL_MISMATCH;
1427 else return CSA_FAIL_NOADDR;
1432 /*************************************************
1433 * Verify Client SMTP Authorization *
1434 *************************************************/
1436 /* Called from acl_verify() below. This routine calls dns_lookup_special()
1437 to find the CSA SRV record corresponding to the domain argument, or
1438 $sender_helo_name if no argument is provided. It then checks that the
1439 client is authorized, and that its IP address corresponds to the SRV
1440 target's address by calling acl_verify_csa_address() above. The address
1441 should have been returned in the DNS response's ADDITIONAL section, but if
1442 not we perform another DNS lookup to get it.
1445 domain pointer to optional parameter following verify = csa
1447 Returns: CSA_UNKNOWN no valid CSA record found
1448 CSA_OK successfully authorized
1449 CSA_FAIL_* client is definitely not authorized
1450 CSA_DEFER_* there was a DNS problem
1454 acl_verify_csa(const uschar *domain)
1457 const uschar *found;
1459 int priority, weight, port;
1466 /* Work out the domain we are using for the CSA lookup. The default is the
1467 client's HELO domain. If the client has not said HELO, use its IP address
1468 instead. If it's a local client (exim -bs), CSA isn't applicable. */
1470 while (isspace(*domain) && *domain != '\0') ++domain;
1471 if (*domain == '\0') domain = sender_helo_name;
1472 if (domain == NULL) domain = sender_host_address;
1473 if (sender_host_address == NULL) return CSA_UNKNOWN;
1475 /* If we have an address literal, strip off the framing ready for turning it
1476 into a domain. The framing consists of matched square brackets possibly
1477 containing a keyword and a colon before the actual IP address. */
1479 if (domain[0] == '[')
1481 const uschar *start = Ustrchr(domain, ':');
1482 if (start == NULL) start = domain;
1483 domain = string_copyn(start + 1, Ustrlen(start) - 2);
1486 /* Turn domains that look like bare IP addresses into domains in the reverse
1487 DNS. This code also deals with address literals and $sender_host_address. It's
1488 not quite kosher to treat bare domains such as EHLO 192.0.2.57 the same as
1489 address literals, but it's probably the most friendly thing to do. This is an
1490 extension to CSA, so we allow it to be turned off for proper conformance. */
1492 if (string_is_ip_address(domain, NULL) != 0)
1494 if (!dns_csa_use_reverse) return CSA_UNKNOWN;
1495 dns_build_reverse(domain, target);
1499 /* Find out if we've already done the CSA check for this domain. If we have,
1500 return the same result again. Otherwise build a new cached result structure
1501 for this domain. The name is filled in now, and the value is filled in when
1502 we return from this function. */
1504 t = tree_search(csa_cache, domain);
1505 if (t != NULL) return t->data.val;
1507 t = store_get_perm(sizeof(tree_node) + Ustrlen(domain));
1508 Ustrcpy(t->name, domain);
1509 (void)tree_insertnode(&csa_cache, t);
1511 /* Now we are ready to do the actual DNS lookup(s). */
1514 switch (dns_special_lookup(&dnsa, domain, T_CSA, &found))
1516 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1519 return t->data.val = CSA_DEFER_SRV;
1521 /* If we found nothing, the client's authorization is unknown. */
1525 return t->data.val = CSA_UNKNOWN;
1527 /* We got something! Go on to look at the reply in more detail. */
1533 /* Scan the reply for well-formed CSA SRV records. */
1535 for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS);
1537 rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT))
1539 if (rr->type != T_SRV) continue;
1541 /* Extract the numerical SRV fields (p is incremented) */
1544 GETSHORT(priority, p);
1545 GETSHORT(weight, p);
1549 debug_printf("CSA priority=%d weight=%d port=%d\n", priority, weight, port);
1551 /* Check the CSA version number */
1553 if (priority != 1) continue;
1555 /* If the domain does not have a CSA SRV record of its own (i.e. the domain
1556 found by dns_special_lookup() is a parent of the one we asked for), we check
1557 the subdomain assertions in the port field. At the moment there's only one
1558 assertion: legitimate SMTP clients are all explicitly authorized with CSA
1559 SRV records of their own. */
1561 if (Ustrcmp(found, domain) != 0)
1564 return t->data.val = CSA_FAIL_EXPLICIT;
1566 return t->data.val = CSA_UNKNOWN;
1569 /* This CSA SRV record refers directly to our domain, so we check the value
1570 in the weight field to work out the domain's authorization. 0 and 1 are
1571 unauthorized; 3 means the client is authorized but we can't check the IP
1572 address in order to authenticate it, so we treat it as unknown; values
1573 greater than 3 are undefined. */
1575 if (weight < 2) return t->data.val = CSA_FAIL_DOMAIN;
1577 if (weight > 2) continue;
1579 /* Weight == 2, which means the domain is authorized. We must check that the
1580 client's IP address is listed as one of the SRV target addresses. Save the
1581 target hostname then break to scan the additional data for its addresses. */
1583 (void)dn_expand(dnsa.answer, dnsa.answer + dnsa.answerlen, p,
1584 (DN_EXPAND_ARG4_TYPE)target, sizeof(target));
1586 DEBUG(D_acl) debug_printf("CSA target is %s\n", target);
1591 /* If we didn't break the loop then no appropriate records were found. */
1593 if (rr == NULL) return t->data.val = CSA_UNKNOWN;
1595 /* Do not check addresses if the target is ".", in accordance with RFC 2782.
1596 A target of "." indicates there are no valid addresses, so the client cannot
1597 be authorized. (This is an odd configuration because weight=2 target=. is
1598 equivalent to weight=1, but we check for it in order to keep load off the
1599 root name servers.) Note that dn_expand() turns "." into "". */
1601 if (Ustrcmp(target, "") == 0) return t->data.val = CSA_FAIL_NOADDR;
1603 /* Scan the additional section of the CSA SRV reply for addresses belonging
1604 to the target. If the name server didn't return any additional data (e.g.
1605 because it does not fully support SRV records), we need to do another lookup
1606 to obtain the target addresses; otherwise we have a definitive result. */
1608 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ADDITIONAL, target);
1609 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1611 /* The DNS lookup type corresponds to the IP version used by the client. */
1614 if (Ustrchr(sender_host_address, ':') != NULL)
1617 #endif /* HAVE_IPV6 */
1621 lookup_dnssec_authenticated = NULL;
1622 switch (dns_lookup(&dnsa, target, type, NULL))
1624 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1627 return t->data.val = CSA_DEFER_ADDR;
1629 /* If the query succeeded, scan the addresses and return the result. */
1632 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ANSWERS, target);
1633 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1634 /* else fall through */
1636 /* If the target has no IP addresses, the client cannot have an authorized
1637 IP address. However, if the target site uses A6 records (not AAAA records)
1638 we have to do yet another lookup in order to check them. */
1642 return t->data.val = CSA_FAIL_NOADDR;
1648 /*************************************************
1649 * Handle verification (address & other) *
1650 *************************************************/
1652 enum { VERIFY_REV_HOST_LKUP, VERIFY_CERT, VERIFY_HELO, VERIFY_CSA, VERIFY_HDR_SYNTAX,
1653 VERIFY_NOT_BLIND, VERIFY_HDR_SNDR, VERIFY_SNDR, VERIFY_RCPT,
1654 VERIFY_HDR_NAMES_ASCII
1659 unsigned where_allowed; /* bitmap */
1660 BOOL no_options; /* Never has /option(s) following */
1661 unsigned alt_opt_sep; /* >0 Non-/ option separator (custom parser) */
1663 static verify_type_t verify_type_list[] = {
1664 { US"reverse_host_lookup", VERIFY_REV_HOST_LKUP, ~0, FALSE, 0 },
1665 { US"certificate", VERIFY_CERT, ~0, TRUE, 0 },
1666 { US"helo", VERIFY_HELO, ~0, TRUE, 0 },
1667 { US"csa", VERIFY_CSA, ~0, FALSE, 0 },
1668 { US"header_syntax", VERIFY_HDR_SYNTAX, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), TRUE, 0 },
1669 { US"not_blind", VERIFY_NOT_BLIND, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), TRUE, 0 },
1670 { US"header_sender", VERIFY_HDR_SNDR, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), FALSE, 0 },
1671 { US"sender", VERIFY_SNDR, (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)
1672 |(1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP),
1674 { US"recipient", VERIFY_RCPT, (1<<ACL_WHERE_RCPT), FALSE, 0 },
1675 { US"header_names_ascii", VERIFY_HDR_NAMES_ASCII, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), TRUE, 0 }
1679 enum { CALLOUT_DEFER_OK, CALLOUT_NOCACHE, CALLOUT_RANDOM, CALLOUT_USE_SENDER,
1680 CALLOUT_USE_POSTMASTER, CALLOUT_POSTMASTER, CALLOUT_FULLPOSTMASTER,
1681 CALLOUT_MAILFROM, CALLOUT_POSTMASTER_MAILFROM, CALLOUT_MAXWAIT, CALLOUT_CONNECT,
1688 BOOL has_option; /* Has =option(s) following */
1689 BOOL timeval; /* Has a time value */
1691 static callout_opt_t callout_opt_list[] = {
1692 { US"defer_ok", CALLOUT_DEFER_OK, 0, FALSE, FALSE },
1693 { US"no_cache", CALLOUT_NOCACHE, vopt_callout_no_cache, FALSE, FALSE },
1694 { US"random", CALLOUT_RANDOM, vopt_callout_random, FALSE, FALSE },
1695 { US"use_sender", CALLOUT_USE_SENDER, vopt_callout_recipsender, FALSE, FALSE },
1696 { US"use_postmaster", CALLOUT_USE_POSTMASTER,vopt_callout_recippmaster, FALSE, FALSE },
1697 { US"postmaster_mailfrom",CALLOUT_POSTMASTER_MAILFROM,0, TRUE, FALSE },
1698 { US"postmaster", CALLOUT_POSTMASTER, 0, FALSE, FALSE },
1699 { US"fullpostmaster", CALLOUT_FULLPOSTMASTER,vopt_callout_fullpm, FALSE, FALSE },
1700 { US"mailfrom", CALLOUT_MAILFROM, 0, TRUE, FALSE },
1701 { US"maxwait", CALLOUT_MAXWAIT, 0, TRUE, TRUE },
1702 { US"connect", CALLOUT_CONNECT, 0, TRUE, TRUE },
1703 { NULL, CALLOUT_TIME, 0, FALSE, TRUE }
1708 /* This function implements the "verify" condition. It is called when
1709 encountered in any ACL, because some tests are almost always permitted. Some
1710 just don't make sense, and always fail (for example, an attempt to test a host
1711 lookup for a non-TCP/IP message). Others are restricted to certain ACLs.
1714 where where called from
1715 addr the recipient address that the ACL is handling, or NULL
1716 arg the argument of "verify"
1717 user_msgptr pointer for user message
1718 log_msgptr pointer for log message
1719 basic_errno where to put verify errno
1721 Returns: OK verification condition succeeded
1722 FAIL verification failed
1723 DEFER there was a problem verifying
1728 acl_verify(int where, address_item *addr, const uschar *arg,
1729 uschar **user_msgptr, uschar **log_msgptr, int *basic_errno)
1733 int callout_overall = -1;
1734 int callout_connect = -1;
1735 int verify_options = 0;
1737 BOOL verify_header_sender = FALSE;
1738 BOOL defer_ok = FALSE;
1739 BOOL callout_defer_ok = FALSE;
1740 BOOL no_details = FALSE;
1741 BOOL success_on_redirect = FALSE;
1742 address_item *sender_vaddr = NULL;
1743 uschar *verify_sender_address = NULL;
1744 uschar *pm_mailfrom = NULL;
1745 uschar *se_mailfrom = NULL;
1747 /* Some of the verify items have slash-separated options; some do not. Diagnose
1748 an error if options are given for items that don't expect them.
1751 uschar *slash = Ustrchr(arg, '/');
1752 const uschar *list = arg;
1753 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
1756 if (ss == NULL) goto BAD_VERIFY;
1758 /* Handle name/address consistency verification in a separate function. */
1760 for (vp= verify_type_list;
1761 (char *)vp < (char *)verify_type_list + sizeof(verify_type_list);
1764 if (vp->alt_opt_sep ? strncmpic(ss, vp->name, vp->alt_opt_sep) == 0
1765 : strcmpic (ss, vp->name) == 0)
1767 if ((char *)vp >= (char *)verify_type_list + sizeof(verify_type_list))
1770 if (vp->no_options && slash != NULL)
1772 *log_msgptr = string_sprintf("unexpected '/' found in \"%s\" "
1773 "(this verify item has no options)", arg);
1776 if (!(vp->where_allowed & (1<<where)))
1778 *log_msgptr = string_sprintf("cannot verify %s in ACL for %s", vp->name, acl_wherenames[where]);
1783 case VERIFY_REV_HOST_LKUP:
1784 if (sender_host_address == NULL) return OK;
1785 if ((rc = acl_verify_reverse(user_msgptr, log_msgptr)) == DEFER)
1786 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size)))
1787 if (strcmpic(ss, US"defer_ok") == 0)
1792 /* TLS certificate verification is done at STARTTLS time; here we just
1793 test whether it was successful or not. (This is for optional verification; for
1794 mandatory verification, the connection doesn't last this long.) */
1796 if (tls_in.certificate_verified) return OK;
1797 *user_msgptr = US"no verified certificate";
1801 /* We can test the result of optional HELO verification that might have
1802 occurred earlier. If not, we can attempt the verification now. */
1804 if (!helo_verified && !helo_verify_failed) smtp_verify_helo();
1805 return helo_verified? OK : FAIL;
1808 /* Do Client SMTP Authorization checks in a separate function, and turn the
1809 result code into user-friendly strings. */
1811 rc = acl_verify_csa(list);
1812 *log_msgptr = *user_msgptr = string_sprintf("client SMTP authorization %s",
1813 csa_reason_string[rc]);
1814 csa_status = csa_status_string[rc];
1815 DEBUG(D_acl) debug_printf("CSA result %s\n", csa_status);
1816 return csa_return_code[rc];
1818 case VERIFY_HDR_SYNTAX:
1819 /* Check that all relevant header lines have the correct syntax. If there is
1820 a syntax error, we return details of the error to the sender if configured to
1821 send out full details. (But a "message" setting on the ACL can override, as
1824 rc = verify_check_headers(log_msgptr);
1825 if (rc != OK && *log_msgptr)
1826 if (smtp_return_error_details)
1827 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1829 acl_verify_message = *log_msgptr;
1832 case VERIFY_HDR_NAMES_ASCII:
1833 /* Check that all header names are true 7 bit strings
1834 See RFC 5322, 2.2. and RFC 6532, 3. */
1836 rc = verify_check_header_names_ascii(log_msgptr);
1837 if (rc != OK && smtp_return_error_details && *log_msgptr != NULL)
1838 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1841 case VERIFY_NOT_BLIND:
1842 /* Check that no recipient of this message is "blind", that is, every envelope
1843 recipient must be mentioned in either To: or Cc:. */
1845 rc = verify_check_notblind();
1848 *log_msgptr = string_sprintf("bcc recipient detected");
1849 if (smtp_return_error_details)
1850 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1854 /* The remaining verification tests check recipient and sender addresses,
1855 either from the envelope or from the header. There are a number of
1856 slash-separated options that are common to all of them. */
1858 case VERIFY_HDR_SNDR:
1859 verify_header_sender = TRUE;
1863 /* In the case of a sender, this can optionally be followed by an address to use
1864 in place of the actual sender (rare special-case requirement). */
1868 verify_sender_address = sender_address;
1871 while (isspace(*s)) s++;
1872 if (*s++ != '=') goto BAD_VERIFY;
1873 while (isspace(*s)) s++;
1874 verify_sender_address = string_copy(s);
1885 /* Remaining items are optional; they apply to sender and recipient
1886 verification, including "header sender" verification. */
1888 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size))
1891 if (strcmpic(ss, US"defer_ok") == 0) defer_ok = TRUE;
1892 else if (strcmpic(ss, US"no_details") == 0) no_details = TRUE;
1893 else if (strcmpic(ss, US"success_on_redirect") == 0) success_on_redirect = TRUE;
1895 /* These two old options are left for backwards compatibility */
1897 else if (strcmpic(ss, US"callout_defer_ok") == 0)
1899 callout_defer_ok = TRUE;
1900 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1903 else if (strcmpic(ss, US"check_postmaster") == 0)
1906 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1909 /* The callout option has a number of sub-options, comma separated */
1911 else if (strncmpic(ss, US"callout", 7) == 0)
1913 callout = CALLOUT_TIMEOUT_DEFAULT;
1917 while (isspace(*ss)) ss++;
1920 const uschar * sublist = ss;
1924 while (isspace(*sublist)) sublist++;
1926 while ((opt = string_nextinlist(&sublist, &optsep, buffer, sizeof(buffer)))
1930 double period = 1.0F;
1932 for (op= callout_opt_list; op->name; op++)
1933 if (strncmpic(opt, op->name, Ustrlen(op->name)) == 0)
1936 verify_options |= op->flag;
1939 opt += Ustrlen(op->name);
1940 while (isspace(*opt)) opt++;
1943 *log_msgptr = string_sprintf("'=' expected after "
1944 "\"%s\" in ACL verify condition \"%s\"", op->name, arg);
1947 while (isspace(*opt)) opt++;
1951 period = readconf_readtime(opt, 0, FALSE);
1954 *log_msgptr = string_sprintf("bad time value in ACL condition "
1955 "\"verify %s\"", arg);
1962 case CALLOUT_DEFER_OK: callout_defer_ok = TRUE; break;
1963 case CALLOUT_POSTMASTER: pm_mailfrom = US""; break;
1964 case CALLOUT_FULLPOSTMASTER: pm_mailfrom = US""; break;
1965 case CALLOUT_MAILFROM:
1966 if (!verify_header_sender)
1968 *log_msgptr = string_sprintf("\"mailfrom\" is allowed as a "
1969 "callout option only for verify=header_sender (detected in ACL "
1970 "condition \"%s\")", arg);
1973 se_mailfrom = string_copy(opt);
1975 case CALLOUT_POSTMASTER_MAILFROM: pm_mailfrom = string_copy(opt); break;
1976 case CALLOUT_MAXWAIT: callout_overall = period; break;
1977 case CALLOUT_CONNECT: callout_connect = period; break;
1978 case CALLOUT_TIME: callout = period; break;
1984 *log_msgptr = string_sprintf("'=' expected after \"callout\" in "
1985 "ACL condition \"%s\"", arg);
1991 /* Option not recognized */
1995 *log_msgptr = string_sprintf("unknown option \"%s\" in ACL "
1996 "condition \"verify %s\"", ss, arg);
2001 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster)) ==
2002 (vopt_callout_recipsender|vopt_callout_recippmaster))
2004 *log_msgptr = US"only one of use_sender and use_postmaster can be set "
2005 "for a recipient callout";
2009 /* Handle sender-in-header verification. Default the user message to the log
2010 message if giving out verification details. */
2012 if (verify_header_sender)
2015 rc = verify_check_header_address(user_msgptr, log_msgptr, callout,
2016 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, verify_options,
2020 *basic_errno = verrno;
2021 if (smtp_return_error_details)
2023 if (*user_msgptr == NULL && *log_msgptr != NULL)
2024 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
2025 if (rc == DEFER) acl_temp_details = TRUE;
2030 /* Handle a sender address. The default is to verify *the* sender address, but
2031 optionally a different address can be given, for special requirements. If the
2032 address is empty, we are dealing with a bounce message that has no sender, so
2033 we cannot do any checking. If the real sender address gets rewritten during
2034 verification (e.g. DNS widening), set the flag to stop it being rewritten again
2035 during message reception.
2037 A list of verified "sender" addresses is kept to try to avoid doing to much
2038 work repetitively when there are multiple recipients in a message and they all
2039 require sender verification. However, when callouts are involved, it gets too
2040 complicated because different recipients may require different callout options.
2041 Therefore, we always do a full sender verify when any kind of callout is
2042 specified. Caching elsewhere, for instance in the DNS resolver and in the
2043 callout handling, should ensure that this is not terribly inefficient. */
2045 else if (verify_sender_address != NULL)
2047 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster))
2050 *log_msgptr = US"use_sender or use_postmaster cannot be used for a "
2051 "sender verify callout";
2055 sender_vaddr = verify_checked_sender(verify_sender_address);
2056 if (sender_vaddr != NULL && /* Previously checked */
2057 callout <= 0) /* No callout needed this time */
2059 /* If the "routed" flag is set, it means that routing worked before, so
2060 this check can give OK (the saved return code value, if set, belongs to a
2061 callout that was done previously). If the "routed" flag is not set, routing
2062 must have failed, so we use the saved return code. */
2064 if (testflag(sender_vaddr, af_verify_routed)) rc = OK; else
2066 rc = sender_vaddr->special_action;
2067 *basic_errno = sender_vaddr->basic_errno;
2069 HDEBUG(D_acl) debug_printf("using cached sender verify result\n");
2072 /* Do a new verification, and cache the result. The cache is used to avoid
2073 verifying the sender multiple times for multiple RCPTs when callouts are not
2074 specified (see comments above).
2076 The cache is also used on failure to give details in response to the first
2077 RCPT that gets bounced for this reason. However, this can be suppressed by
2078 the no_details option, which sets the flag that says "this detail has already
2079 been sent". The cache normally contains just one address, but there may be
2080 more in esoteric circumstances. */
2085 uschar *save_address_data = deliver_address_data;
2087 sender_vaddr = deliver_make_addr(verify_sender_address, TRUE);
2089 if ((sender_vaddr->prop.utf8_msg = message_smtputf8))
2091 sender_vaddr->prop.utf8_downcvt = message_utf8_downconvert == 1;
2092 sender_vaddr->prop.utf8_downcvt_maybe = message_utf8_downconvert == -1;
2095 if (no_details) setflag(sender_vaddr, af_sverify_told);
2096 if (verify_sender_address[0] != 0)
2098 /* If this is the real sender address, save the unrewritten version
2099 for use later in receive. Otherwise, set a flag so that rewriting the
2100 sender in verify_address() does not update sender_address. */
2102 if (verify_sender_address == sender_address)
2103 sender_address_unrewritten = sender_address;
2105 verify_options |= vopt_fake_sender;
2107 if (success_on_redirect)
2108 verify_options |= vopt_success_on_redirect;
2110 /* The recipient, qualify, and expn options are never set in
2113 rc = verify_address(sender_vaddr, NULL, verify_options, callout,
2114 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, &routed);
2116 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
2120 if (Ustrcmp(sender_vaddr->address, verify_sender_address) != 0)
2122 DEBUG(D_acl) debug_printf("sender %s verified ok as %s\n",
2123 verify_sender_address, sender_vaddr->address);
2127 DEBUG(D_acl) debug_printf("sender %s verified ok\n",
2128 verify_sender_address);
2131 else *basic_errno = sender_vaddr->basic_errno;
2133 else rc = OK; /* Null sender */
2135 /* Cache the result code */
2137 if (routed) setflag(sender_vaddr, af_verify_routed);
2138 if (callout > 0) setflag(sender_vaddr, af_verify_callout);
2139 sender_vaddr->special_action = rc;
2140 sender_vaddr->next = sender_verified_list;
2141 sender_verified_list = sender_vaddr;
2143 /* Restore the recipient address data, which might have been clobbered by
2144 the sender verification. */
2146 deliver_address_data = save_address_data;
2149 /* Put the sender address_data value into $sender_address_data */
2151 sender_address_data = sender_vaddr->prop.address_data;
2154 /* A recipient address just gets a straightforward verify; again we must handle
2155 the DEFER overrides. */
2161 if (success_on_redirect)
2162 verify_options |= vopt_success_on_redirect;
2164 /* We must use a copy of the address for verification, because it might
2168 rc = verify_address(&addr2, NULL, verify_options|vopt_is_recipient, callout,
2169 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, NULL);
2170 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
2172 *basic_errno = addr2.basic_errno;
2173 *log_msgptr = addr2.message;
2174 *user_msgptr = (addr2.user_message != NULL)?
2175 addr2.user_message : addr2.message;
2177 /* Allow details for temporary error if the address is so flagged. */
2178 if (testflag((&addr2), af_pass_message)) acl_temp_details = TRUE;
2180 /* Make $address_data visible */
2181 deliver_address_data = addr2.prop.address_data;
2184 /* We have a result from the relevant test. Handle defer overrides first. */
2186 if (rc == DEFER && (defer_ok ||
2187 (callout_defer_ok && *basic_errno == ERRNO_CALLOUTDEFER)))
2189 HDEBUG(D_acl) debug_printf("verify defer overridden by %s\n",
2190 defer_ok? "defer_ok" : "callout_defer_ok");
2194 /* If we've failed a sender, set up a recipient message, and point
2195 sender_verified_failed to the address item that actually failed. */
2197 if (rc != OK && verify_sender_address != NULL)
2200 *log_msgptr = *user_msgptr = US"Sender verify failed";
2201 else if (*basic_errno != ERRNO_CALLOUTDEFER)
2202 *log_msgptr = *user_msgptr = US"Could not complete sender verify";
2205 *log_msgptr = US"Could not complete sender verify callout";
2206 *user_msgptr = smtp_return_error_details? sender_vaddr->user_message :
2210 sender_verified_failed = sender_vaddr;
2213 /* Verifying an address messes up the values of $domain and $local_part,
2214 so reset them before returning if this is a RCPT ACL. */
2218 deliver_domain = addr->domain;
2219 deliver_localpart = addr->local_part;
2223 /* Syntax errors in the verify argument come here. */
2226 *log_msgptr = string_sprintf("expected \"sender[=address]\", \"recipient\", "
2227 "\"helo\", \"header_syntax\", \"header_sender\", \"header_names_ascii\" "
2228 "or \"reverse_host_lookup\" at start of ACL condition "
2229 "\"verify %s\"", arg);
2236 /*************************************************
2237 * Check argument for control= modifier *
2238 *************************************************/
2240 /* Called from acl_check_condition() below
2243 arg the argument string for control=
2244 pptr set to point to the terminating character
2245 where which ACL we are in
2246 log_msgptr for error messages
2248 Returns: CONTROL_xxx value
2252 decode_control(const uschar *arg, const uschar **pptr, int where, uschar **log_msgptr)
2257 for (d = controls_list;
2258 d < controls_list + sizeof(controls_list)/sizeof(control_def);
2261 len = Ustrlen(d->name);
2262 if (Ustrncmp(d->name, arg, len) == 0) break;
2265 if (d >= controls_list + sizeof(controls_list)/sizeof(control_def) ||
2266 (arg[len] != 0 && (!d->has_option || arg[len] != '/')))
2268 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
2269 return CONTROL_ERROR;
2279 /*************************************************
2280 * Return a ratelimit error *
2281 *************************************************/
2283 /* Called from acl_ratelimit() below
2286 log_msgptr for error messages
2287 format format string
2288 ... supplementary arguments
2289 ss ratelimit option name
2290 where ACL_WHERE_xxxx indicating which ACL this is
2296 ratelimit_error(uschar **log_msgptr, const char *format, ...)
2299 uschar buffer[STRING_SPRINTF_BUFFER_SIZE];
2300 va_start(ap, format);
2301 if (!string_vformat(buffer, sizeof(buffer), format, ap))
2302 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
2303 "string_sprintf expansion was longer than " SIZE_T_FMT, sizeof(buffer));
2305 *log_msgptr = string_sprintf(
2306 "error in arguments to \"ratelimit\" condition: %s", buffer);
2313 /*************************************************
2314 * Handle rate limiting *
2315 *************************************************/
2317 /* Called by acl_check_condition() below to calculate the result
2318 of the ACL ratelimit condition.
2320 Note that the return value might be slightly unexpected: if the
2321 sender's rate is above the limit then the result is OK. This is
2322 similar to the dnslists condition, and is so that you can write
2323 ACL clauses like: defer ratelimit = 15 / 1h
2326 arg the option string for ratelimit=
2327 where ACL_WHERE_xxxx indicating which ACL this is
2328 log_msgptr for error messages
2330 Returns: OK - Sender's rate is above limit
2331 FAIL - Sender's rate is below limit
2332 DEFER - Problem opening ratelimit database
2333 ERROR - Syntax error in options.
2337 acl_ratelimit(const uschar *arg, int where, uschar **log_msgptr)
2339 double limit, period, count;
2342 uschar *unique = NULL;
2344 BOOL leaky = FALSE, strict = FALSE, readonly = FALSE;
2345 BOOL noupdate = FALSE, badacl = FALSE;
2346 int mode = RATE_PER_WHAT;
2348 tree_node **anchor, *t;
2349 open_db dbblock, *dbm;
2351 dbdata_ratelimit *dbd;
2352 dbdata_ratelimit_unique *dbdb;
2355 /* Parse the first two options and record their values in expansion
2356 variables. These variables allow the configuration to have informative
2357 error messages based on rate limits obtained from a table lookup. */
2359 /* First is the maximum number of messages per period / maximum burst
2360 size, which must be greater than or equal to zero. Zero is useful for
2361 rate measurement as opposed to rate limiting. */
2363 sender_rate_limit = string_nextinlist(&arg, &sep, NULL, 0);
2364 if (sender_rate_limit == NULL)
2365 return ratelimit_error(log_msgptr, "sender rate limit not set");
2367 limit = Ustrtod(sender_rate_limit, &ss);
2368 if (tolower(*ss) == 'k') { limit *= 1024.0; ss++; }
2369 else if (tolower(*ss) == 'm') { limit *= 1024.0*1024.0; ss++; }
2370 else if (tolower(*ss) == 'g') { limit *= 1024.0*1024.0*1024.0; ss++; }
2372 if (limit < 0.0 || *ss != '\0')
2373 return ratelimit_error(log_msgptr,
2374 "\"%s\" is not a positive number", sender_rate_limit);
2376 /* Second is the rate measurement period / exponential smoothing time
2377 constant. This must be strictly greater than zero, because zero leads to
2378 run-time division errors. */
2380 sender_rate_period = string_nextinlist(&arg, &sep, NULL, 0);
2381 if (sender_rate_period == NULL) period = -1.0;
2382 else period = readconf_readtime(sender_rate_period, 0, FALSE);
2384 return ratelimit_error(log_msgptr,
2385 "\"%s\" is not a time value", sender_rate_period);
2387 /* By default we are counting one of something, but the per_rcpt,
2388 per_byte, and count options can change this. */
2392 /* Parse the other options. */
2394 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2397 if (strcmpic(ss, US"leaky") == 0) leaky = TRUE;
2398 else if (strcmpic(ss, US"strict") == 0) strict = TRUE;
2399 else if (strcmpic(ss, US"noupdate") == 0) noupdate = TRUE;
2400 else if (strcmpic(ss, US"readonly") == 0) readonly = TRUE;
2401 else if (strcmpic(ss, US"per_cmd") == 0) RATE_SET(mode, PER_CMD);
2402 else if (strcmpic(ss, US"per_conn") == 0)
2404 RATE_SET(mode, PER_CONN);
2405 if (where == ACL_WHERE_NOTSMTP || where == ACL_WHERE_NOTSMTP_START)
2408 else if (strcmpic(ss, US"per_mail") == 0)
2410 RATE_SET(mode, PER_MAIL);
2411 if (where > ACL_WHERE_NOTSMTP) badacl = TRUE;
2413 else if (strcmpic(ss, US"per_rcpt") == 0)
2415 /* If we are running in the RCPT ACL, then we'll count the recipients
2416 one by one, but if we are running when we have accumulated the whole
2417 list then we'll add them all in one batch. */
2418 if (where == ACL_WHERE_RCPT)
2419 RATE_SET(mode, PER_RCPT);
2420 else if (where >= ACL_WHERE_PREDATA && where <= ACL_WHERE_NOTSMTP)
2421 RATE_SET(mode, PER_ALLRCPTS), count = (double)recipients_count;
2422 else if (where == ACL_WHERE_MAIL || where > ACL_WHERE_NOTSMTP)
2423 RATE_SET(mode, PER_RCPT), badacl = TRUE;
2425 else if (strcmpic(ss, US"per_byte") == 0)
2427 /* If we have not yet received the message data and there was no SIZE
2428 declaration on the MAIL comand, then it's safe to just use a value of
2429 zero and let the recorded rate decay as if nothing happened. */
2430 RATE_SET(mode, PER_MAIL);
2431 if (where > ACL_WHERE_NOTSMTP) badacl = TRUE;
2432 else count = message_size < 0 ? 0.0 : (double)message_size;
2434 else if (strcmpic(ss, US"per_addr") == 0)
2436 RATE_SET(mode, PER_RCPT);
2437 if (where != ACL_WHERE_RCPT) badacl = TRUE, unique = US"*";
2438 else unique = string_sprintf("%s@%s", deliver_localpart, deliver_domain);
2440 else if (strncmpic(ss, US"count=", 6) == 0)
2443 count = Ustrtod(ss+6, &e);
2444 if (count < 0.0 || *e != '\0')
2445 return ratelimit_error(log_msgptr,
2446 "\"%s\" is not a positive number", ss);
2448 else if (strncmpic(ss, US"unique=", 7) == 0)
2449 unique = string_copy(ss + 7);
2450 else if (key == NULL)
2451 key = string_copy(ss);
2453 key = string_sprintf("%s/%s", key, ss);
2456 /* Sanity check. When the badacl flag is set the update mode must either
2457 be readonly (which is the default if it is omitted) or, for backwards
2458 compatibility, a combination of noupdate and strict or leaky. */
2460 if (mode == RATE_PER_CLASH)
2461 return ratelimit_error(log_msgptr, "conflicting per_* options");
2462 if (leaky + strict + readonly > 1)
2463 return ratelimit_error(log_msgptr, "conflicting update modes");
2464 if (badacl && (leaky || strict) && !noupdate)
2465 return ratelimit_error(log_msgptr,
2466 "\"%s\" must not have /leaky or /strict option in %s ACL",
2467 ratelimit_option_string[mode], acl_wherenames[where]);
2469 /* Set the default values of any unset options. In readonly mode we
2470 perform the rate computation without any increment so that its value
2471 decays to eventually allow over-limit senders through. */
2473 if (noupdate) readonly = TRUE, leaky = strict = FALSE;
2474 if (badacl) readonly = TRUE;
2475 if (readonly) count = 0.0;
2476 if (!strict && !readonly) leaky = TRUE;
2477 if (mode == RATE_PER_WHAT) mode = RATE_PER_MAIL;
2479 /* Create the lookup key. If there is no explicit key, use sender_host_address.
2480 If there is no sender_host_address (e.g. -bs or acl_not_smtp) then we simply
2481 omit it. The smoothing constant (sender_rate_period) and the per_xxx options
2482 are added to the key because they alter the meaning of the stored data. */
2485 key = (sender_host_address == NULL)? US"" : sender_host_address;
2487 key = string_sprintf("%s/%s/%s%s",
2489 ratelimit_option_string[mode],
2490 unique == NULL ? "" : "unique/",
2494 debug_printf("ratelimit condition count=%.0f %.1f/%s\n", count, limit, key);
2496 /* See if we have already computed the rate by looking in the relevant tree.
2497 For per-connection rate limiting, store tree nodes and dbdata in the permanent
2498 pool so that they survive across resets. In readonly mode we only remember the
2499 result for the rest of this command in case a later command changes it. After
2500 this bit of logic the code is independent of the per_* mode. */
2502 old_pool = store_pool;
2505 anchor = &ratelimiters_cmd;
2508 anchor = &ratelimiters_conn;
2509 store_pool = POOL_PERM;
2513 case RATE_PER_ALLRCPTS:
2514 anchor = &ratelimiters_mail;
2519 anchor = &ratelimiters_cmd;
2522 anchor = NULL; /* silence an "unused" complaint */
2523 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
2524 "internal ACL error: unknown ratelimit mode %d", mode);
2528 t = tree_search(*anchor, key);
2532 /* The following few lines duplicate some of the code below. */
2533 rc = (dbd->rate < limit)? FAIL : OK;
2534 store_pool = old_pool;
2535 sender_rate = string_sprintf("%.1f", dbd->rate);
2537 debug_printf("ratelimit found pre-computed rate %s\n", sender_rate);
2541 /* We aren't using a pre-computed rate, so get a previously recorded rate
2542 from the database, which will be updated and written back if required. */
2544 dbm = dbfn_open(US"ratelimit", O_RDWR, &dbblock, TRUE);
2547 store_pool = old_pool;
2549 HDEBUG(D_acl) debug_printf("ratelimit database not available\n");
2550 *log_msgptr = US"ratelimit database not available";
2553 dbdb = dbfn_read_with_length(dbm, key, &dbdb_size);
2556 gettimeofday(&tv, NULL);
2560 /* Locate the basic ratelimit block inside the DB data. */
2561 HDEBUG(D_acl) debug_printf("ratelimit found key in database\n");
2564 /* Forget the old Bloom filter if it is too old, so that we count each
2565 repeating event once per period. We don't simply clear and re-use the old
2566 filter because we want its size to change if the limit changes. Note that
2567 we keep the dbd pointer for copying the rate into the new data block. */
2569 if(unique != NULL && tv.tv_sec > dbdb->bloom_epoch + period)
2571 HDEBUG(D_acl) debug_printf("ratelimit discarding old Bloom filter\n");
2577 if(unique != NULL && dbdb_size < sizeof(*dbdb))
2579 HDEBUG(D_acl) debug_printf("ratelimit discarding undersize Bloom filter\n");
2584 /* Allocate a new data block if the database lookup failed
2585 or the Bloom filter passed its age limit. */
2591 /* No Bloom filter. This basic ratelimit block is initialized below. */
2592 HDEBUG(D_acl) debug_printf("ratelimit creating new rate data block\n");
2593 dbdb_size = sizeof(*dbd);
2594 dbdb = store_get(dbdb_size);
2599 HDEBUG(D_acl) debug_printf("ratelimit creating new Bloom filter\n");
2601 /* See the long comment below for an explanation of the magic number 2.
2602 The filter has a minimum size in case the rate limit is very small;
2603 this is determined by the definition of dbdata_ratelimit_unique. */
2605 extra = (int)limit * 2 - sizeof(dbdb->bloom);
2606 if (extra < 0) extra = 0;
2607 dbdb_size = sizeof(*dbdb) + extra;
2608 dbdb = store_get(dbdb_size);
2609 dbdb->bloom_epoch = tv.tv_sec;
2610 dbdb->bloom_size = sizeof(dbdb->bloom) + extra;
2611 memset(dbdb->bloom, 0, dbdb->bloom_size);
2613 /* Preserve any basic ratelimit data (which is our longer-term memory)
2614 by copying it from the discarded block. */
2624 /* If we are counting unique events, find out if this event is new or not.
2625 If the client repeats the event during the current period then it should be
2626 counted. We skip this code in readonly mode for efficiency, because any
2627 changes to the filter will be discarded and because count is already set to
2630 if (unique != NULL && !readonly)
2632 /* We identify unique events using a Bloom filter. (You can find my
2633 notes on Bloom filters at http://fanf.livejournal.com/81696.html)
2634 With the per_addr option, an "event" is a recipient address, though the
2635 user can use the unique option to define their own events. We only count
2636 an event if we have not seen it before.
2638 We size the filter according to the rate limit, which (in leaky mode)
2639 is the limit on the population of the filter. We allow 16 bits of space
2640 per entry (see the construction code above) and we set (up to) 8 of them
2641 when inserting an element (see the loop below). The probability of a false
2642 positive (an event we have not seen before but which we fail to count) is
2646 allzero = exp(-numhash * pop / size)
2647 = exp(-0.5 * pop / limit)
2648 fpr = pow(1 - allzero, numhash)
2650 For senders at the limit the fpr is 0.06% or 1 in 1700
2651 and for senders at half the limit it is 0.0006% or 1 in 170000
2653 In strict mode the Bloom filter can fill up beyond the normal limit, in
2654 which case the false positive rate will rise. This means that the
2655 measured rate for very fast senders can bogusly drop off after a while.
2657 At twice the limit, the fpr is 2.5% or 1 in 40
2658 At four times the limit, it is 31% or 1 in 3.2
2660 It takes ln(pop/limit) periods for an over-limit burst of pop events to
2661 decay below the limit, and if this is more than one then the Bloom filter
2662 will be discarded before the decay gets that far. The false positive rate
2663 at this threshold is 9.3% or 1 in 10.7. */
2666 unsigned n, hash, hinc;
2670 /* Instead of using eight independent hash values, we combine two values
2671 using the formula h1 + n * h2. This does not harm the Bloom filter's
2672 performance, and means the amount of hash we need is independent of the
2673 number of bits we set in the filter. */
2675 md5_start(&md5info);
2676 md5_end(&md5info, unique, Ustrlen(unique), md5sum);
2677 hash = md5sum[0] | md5sum[1] << 8 | md5sum[2] << 16 | md5sum[3] << 24;
2678 hinc = md5sum[4] | md5sum[5] << 8 | md5sum[6] << 16 | md5sum[7] << 24;
2680 /* Scan the bits corresponding to this event. A zero bit means we have
2681 not seen it before. Ensure all bits are set to record this event. */
2683 HDEBUG(D_acl) debug_printf("ratelimit checking uniqueness of %s\n", unique);
2686 for (n = 0; n < 8; n++, hash += hinc)
2688 int bit = 1 << (hash % 8);
2689 int byte = (hash / 8) % dbdb->bloom_size;
2690 if ((dbdb->bloom[byte] & bit) == 0)
2692 dbdb->bloom[byte] |= bit;
2697 /* If this event has occurred before, do not count it. */
2701 HDEBUG(D_acl) debug_printf("ratelimit event found in Bloom filter\n");
2705 HDEBUG(D_acl) debug_printf("ratelimit event added to Bloom filter\n");
2708 /* If there was no previous ratelimit data block for this key, initialize
2709 the new one, otherwise update the block from the database. The initial rate
2710 is what would be computed by the code below for an infinite interval. */
2714 HDEBUG(D_acl) debug_printf("ratelimit initializing new key's rate data\n");
2716 dbd->time_stamp = tv.tv_sec;
2717 dbd->time_usec = tv.tv_usec;
2722 /* The smoothed rate is computed using an exponentially weighted moving
2723 average adjusted for variable sampling intervals. The standard EWMA for
2724 a fixed sampling interval is: f'(t) = (1 - a) * f(t) + a * f'(t - 1)
2725 where f() is the measured value and f'() is the smoothed value.
2727 Old data decays out of the smoothed value exponentially, such that data n
2728 samples old is multiplied by a^n. The exponential decay time constant p
2729 is defined such that data p samples old is multiplied by 1/e, which means
2730 that a = exp(-1/p). We can maintain the same time constant for a variable
2731 sampling interval i by using a = exp(-i/p).
2733 The rate we are measuring is messages per period, suitable for directly
2734 comparing with the limit. The average rate between now and the previous
2735 message is period / interval, which we feed into the EWMA as the sample.
2737 It turns out that the number of messages required for the smoothed rate
2738 to reach the limit when they are sent in a burst is equal to the limit.
2739 This can be seen by analysing the value of the smoothed rate after N
2740 messages sent at even intervals. Let k = (1 - a) * p/i
2742 rate_1 = (1 - a) * p/i + a * rate_0
2744 rate_2 = k + a * rate_1
2745 = k + a * k + a^2 * rate_0
2746 rate_3 = k + a * k + a^2 * k + a^3 * rate_0
2747 rate_N = rate_0 * a^N + k * SUM(x=0..N-1)(a^x)
2748 = rate_0 * a^N + k * (1 - a^N) / (1 - a)
2749 = rate_0 * a^N + p/i * (1 - a^N)
2751 When N is large, a^N -> 0 so rate_N -> p/i as desired.
2753 rate_N = p/i + (rate_0 - p/i) * a^N
2754 a^N = (rate_N - p/i) / (rate_0 - p/i)
2755 N * -i/p = log((rate_N - p/i) / (rate_0 - p/i))
2756 N = p/i * log((rate_0 - p/i) / (rate_N - p/i))
2758 Numerical analysis of the above equation, setting the computed rate to
2759 increase from rate_0 = 0 to rate_N = limit, shows that for large sending
2760 rates, p/i, the number of messages N = limit. So limit serves as both the
2761 maximum rate measured in messages per period, and the maximum number of
2762 messages that can be sent in a fast burst. */
2764 double this_time = (double)tv.tv_sec
2765 + (double)tv.tv_usec / 1000000.0;
2766 double prev_time = (double)dbd->time_stamp
2767 + (double)dbd->time_usec / 1000000.0;
2769 /* We must avoid division by zero, and deal gracefully with the clock going
2770 backwards. If we blunder ahead when time is in reverse then the computed
2771 rate will be bogus. To be safe we clamp interval to a very small number. */
2773 double interval = this_time - prev_time <= 0.0 ? 1e-9
2774 : this_time - prev_time;
2776 double i_over_p = interval / period;
2777 double a = exp(-i_over_p);
2779 /* Combine the instantaneous rate (period / interval) with the previous rate
2780 using the smoothing factor a. In order to measure sized events, multiply the
2781 instantaneous rate by the count of bytes or recipients etc. */
2783 dbd->time_stamp = tv.tv_sec;
2784 dbd->time_usec = tv.tv_usec;
2785 dbd->rate = (1 - a) * count / i_over_p + a * dbd->rate;
2787 /* When events are very widely spaced the computed rate tends towards zero.
2788 Although this is accurate it turns out not to be useful for our purposes,
2789 especially when the first event after a long silence is the start of a spam
2790 run. A more useful model is that the rate for an isolated event should be the
2791 size of the event per the period size, ignoring the lack of events outside
2792 the current period and regardless of where the event falls in the period. So,
2793 if the interval was so long that the calculated rate is unhelpfully small, we
2794 re-intialize the rate. In the absence of higher-rate bursts, the condition
2795 below is true if the interval is greater than the period. */
2797 if (dbd->rate < count) dbd->rate = count;
2800 /* Clients sending at the limit are considered to be over the limit.
2801 This matters for edge cases such as a limit of zero, when the client
2802 should be completely blocked. */
2804 rc = (dbd->rate < limit)? FAIL : OK;
2806 /* Update the state if the rate is low or if we are being strict. If we
2807 are in leaky mode and the sender's rate is too high, we do not update
2808 the recorded rate in order to avoid an over-aggressive sender's retry
2809 rate preventing them from getting any email through. If readonly is set,
2810 neither leaky nor strict are set, so we do not do any updates. */
2812 if ((rc == FAIL && leaky) || strict)
2814 dbfn_write(dbm, key, dbdb, dbdb_size);
2815 HDEBUG(D_acl) debug_printf("ratelimit db updated\n");
2819 HDEBUG(D_acl) debug_printf("ratelimit db not updated: %s\n",
2820 readonly? "readonly mode" : "over the limit, but leaky");
2825 /* Store the result in the tree for future reference. */
2827 t = store_get(sizeof(tree_node) + Ustrlen(key));
2829 Ustrcpy(t->name, key);
2830 (void)tree_insertnode(anchor, t);
2832 /* We create the formatted version of the sender's rate very late in
2833 order to ensure that it is done using the correct storage pool. */
2835 store_pool = old_pool;
2836 sender_rate = string_sprintf("%.1f", dbd->rate);
2839 debug_printf("ratelimit computed rate %s\n", sender_rate);
2846 /*************************************************
2847 * The udpsend ACL modifier *
2848 *************************************************/
2850 /* Called by acl_check_condition() below.
2853 arg the option string for udpsend=
2854 log_msgptr for error messages
2856 Returns: OK - Completed.
2857 DEFER - Problem with DNS lookup.
2858 ERROR - Syntax error in options.
2862 acl_udpsend(const uschar *arg, uschar **log_msgptr)
2874 hostname = string_nextinlist(&arg, &sep, NULL, 0);
2875 portstr = string_nextinlist(&arg, &sep, NULL, 0);
2877 if (hostname == NULL)
2879 *log_msgptr = US"missing destination host in \"udpsend\" modifier";
2882 if (portstr == NULL)
2884 *log_msgptr = US"missing destination port in \"udpsend\" modifier";
2889 *log_msgptr = US"missing datagram payload in \"udpsend\" modifier";
2892 portnum = Ustrtol(portstr, &portend, 10);
2893 if (*portend != '\0')
2895 *log_msgptr = US"bad destination port in \"udpsend\" modifier";
2899 /* Make a single-item host list. */
2900 h = store_get(sizeof(host_item));
2901 memset(h, 0, sizeof(host_item));
2906 if (string_is_ip_address(hostname, NULL))
2907 h->address = hostname, r = HOST_FOUND;
2909 r = host_find_byname(h, NULL, 0, NULL, FALSE);
2910 if (r == HOST_FIND_FAILED || r == HOST_FIND_AGAIN)
2912 *log_msgptr = US"DNS lookup failed in \"udpsend\" modifier";
2917 debug_printf("udpsend [%s]:%d %s\n", h->address, portnum, arg);
2919 r = s = ip_connectedsocket(SOCK_DGRAM, h->address, portnum, portnum,
2921 if (r < 0) goto defer;
2923 r = send(s, arg, len, 0);
2926 errstr = US strerror(errno);
2934 string_sprintf("\"udpsend\" truncated from %d to %d octets", len, r);
2939 debug_printf("udpsend %d bytes\n", r);
2944 *log_msgptr = string_sprintf("\"udpsend\" failed: %s", errstr);
2950 /*************************************************
2951 * Handle conditions/modifiers on an ACL item *
2952 *************************************************/
2954 /* Called from acl_check() below.
2958 cb ACL condition block - if NULL, result is OK
2959 where where called from
2960 addr the address being checked for RCPT, or NULL
2961 level the nesting level
2962 epp pointer to pass back TRUE if "endpass" encountered
2963 (applies only to "accept" and "discard")
2964 user_msgptr user message pointer
2965 log_msgptr log message pointer
2966 basic_errno pointer to where to put verify error
2968 Returns: OK - all conditions are met
2969 DISCARD - an "acl" condition returned DISCARD - only allowed
2970 for "accept" or "discard" verbs
2971 FAIL - at least one condition fails
2972 FAIL_DROP - an "acl" condition returned FAIL_DROP
2973 DEFER - can't tell at the moment (typically, lookup defer,
2974 but can be temporary callout problem)
2975 ERROR - ERROR from nested ACL or expansion failure or other
2980 acl_check_condition(int verb, acl_condition_block *cb, int where,
2981 address_item *addr, int level, BOOL *epp, uschar **user_msgptr,
2982 uschar **log_msgptr, int *basic_errno)
2984 uschar *user_message = NULL;
2985 uschar *log_message = NULL;
2986 uschar *debug_tag = NULL;
2987 uschar *debug_opts = NULL;
2989 #ifdef WITH_CONTENT_SCAN
2993 for (; cb != NULL; cb = cb->next)
2998 /* The message and log_message items set up messages to be used in
2999 case of rejection. They are expanded later. */
3001 if (cb->type == ACLC_MESSAGE)
3003 HDEBUG(D_acl) debug_printf(" message: %s\n", cb->arg);
3004 user_message = cb->arg;
3008 if (cb->type == ACLC_LOG_MESSAGE)
3010 HDEBUG(D_acl) debug_printf("l_message: %s\n", cb->arg);
3011 log_message = cb->arg;
3015 /* The endpass "condition" just sets a flag to show it occurred. This is
3016 checked at compile time to be on an "accept" or "discard" item. */
3018 if (cb->type == ACLC_ENDPASS)
3024 /* For other conditions and modifiers, the argument is expanded now for some
3025 of them, but not for all, because expansion happens down in some lower level
3026 checking functions in some cases. */
3028 if (cond_expand_at_top[cb->type])
3030 arg = expand_string(cb->arg);
3033 if (expand_string_forcedfail) continue;
3034 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s",
3035 cb->arg, expand_string_message);
3036 return search_find_defer? DEFER : ERROR;
3041 /* Show condition, and expanded condition if it's different */
3046 debug_printf("check %s%s %n",
3047 (!cond_modifiers[cb->type] && cb->u.negated)? "!":"",
3048 conditions[cb->type], &lhswidth);
3050 if (cb->type == ACLC_SET)
3052 debug_printf("acl_%s ", cb->u.varname);
3053 lhswidth += 5 + Ustrlen(cb->u.varname);
3056 debug_printf("= %s\n", cb->arg);
3059 debug_printf("%.*s= %s\n", lhswidth,
3063 /* Check that this condition makes sense at this time */
3065 if ((cond_forbids[cb->type] & (1 << where)) != 0)
3067 *log_msgptr = string_sprintf("cannot %s %s condition in %s ACL",
3068 cond_modifiers[cb->type]? "use" : "test",
3069 conditions[cb->type], acl_wherenames[where]);
3073 /* Run the appropriate test for each condition, or take the appropriate
3074 action for the remaining modifiers. */
3078 case ACLC_ADD_HEADER:
3082 /* A nested ACL that returns "discard" makes sense only for an "accept" or
3086 rc = acl_check_wargs(where, addr, arg, level+1, user_msgptr, log_msgptr);
3087 if (rc == DISCARD && verb != ACL_ACCEPT && verb != ACL_DISCARD)
3089 *log_msgptr = string_sprintf("nested ACL returned \"discard\" for "
3090 "\"%s\" command (only allowed with \"accept\" or \"discard\")",
3096 case ACLC_AUTHENTICATED:
3097 rc = (sender_host_authenticated == NULL)? FAIL :
3098 match_isinlist(sender_host_authenticated, &arg, 0, NULL, NULL, MCL_STRING,
3102 #ifdef EXPERIMENTAL_BRIGHTMAIL
3103 case ACLC_BMI_OPTIN:
3105 int old_pool = store_pool;
3106 store_pool = POOL_PERM;
3107 bmi_current_optin = string_copy(arg);
3108 store_pool = old_pool;
3113 case ACLC_CONDITION:
3114 /* The true/false parsing here should be kept in sync with that used in
3115 expand.c when dealing with ECOND_BOOL so that we don't have too many
3116 different definitions of what can be a boolean. */
3118 ? Ustrspn(arg+1, "0123456789") == Ustrlen(arg+1) /* Negative number */
3119 : Ustrspn(arg, "0123456789") == Ustrlen(arg)) /* Digits, or empty */
3120 rc = (Uatoi(arg) == 0)? FAIL : OK;
3122 rc = (strcmpic(arg, US"no") == 0 ||
3123 strcmpic(arg, US"false") == 0)? FAIL :
3124 (strcmpic(arg, US"yes") == 0 ||
3125 strcmpic(arg, US"true") == 0)? OK : DEFER;
3127 *log_msgptr = string_sprintf("invalid \"condition\" value \"%s\"", arg);
3130 case ACLC_CONTINUE: /* Always succeeds */
3135 const uschar *p = NULL;
3136 control_type = decode_control(arg, &p, where, log_msgptr);
3138 /* Check if this control makes sense at this time */
3140 if ((control_forbids[control_type] & (1 << where)) != 0)
3142 *log_msgptr = string_sprintf("cannot use \"control=%s\" in %s ACL",
3143 controls[control_type], acl_wherenames[where]);
3147 switch(control_type)
3149 case CONTROL_AUTH_UNADVERTISED:
3150 allow_auth_unadvertised = TRUE;
3153 #ifdef EXPERIMENTAL_BRIGHTMAIL
3154 case CONTROL_BMI_RUN:
3159 #ifndef DISABLE_DKIM
3160 case CONTROL_DKIM_VERIFY:
3161 dkim_disable_verify = TRUE;
3162 #ifdef EXPERIMENTAL_DMARC
3163 /* Since DKIM was blocked, skip DMARC too */
3164 dmarc_disable_verify = TRUE;
3165 dmarc_enable_forensic = FALSE;
3170 #ifdef EXPERIMENTAL_DMARC
3171 case CONTROL_DMARC_VERIFY:
3172 dmarc_disable_verify = TRUE;
3175 case CONTROL_DMARC_FORENSIC:
3176 dmarc_enable_forensic = TRUE;
3183 int fd, af, level, optname, value;
3184 /* If we are acting on stdin, the setsockopt may fail if stdin is not
3185 a socket; we can accept that, we'll just debug-log failures anyway. */
3186 fd = fileno(smtp_in);
3187 af = ip_get_address_family(fd);
3191 debug_printf("smtp input is probably not a socket [%s], not setting DSCP\n",
3195 if (dscp_lookup(p+1, af, &level, &optname, &value))
3197 if (setsockopt(fd, level, optname, &value, sizeof(value)) < 0)
3199 HDEBUG(D_acl) debug_printf("failed to set input DSCP[%s]: %s\n",
3200 p+1, strerror(errno));
3204 HDEBUG(D_acl) debug_printf("set input DSCP to \"%s\"\n", p+1);
3209 *log_msgptr = string_sprintf("unrecognised DSCP value in \"control=%s\"", arg);
3215 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3223 case CONTROL_CASEFUL_LOCAL_PART:
3224 deliver_localpart = addr->cc_local_part;
3227 case CONTROL_CASELOWER_LOCAL_PART:
3228 deliver_localpart = addr->lc_local_part;
3231 case CONTROL_ENFORCE_SYNC:
3232 smtp_enforce_sync = TRUE;
3235 case CONTROL_NO_ENFORCE_SYNC:
3236 smtp_enforce_sync = FALSE;
3239 #ifdef WITH_CONTENT_SCAN
3240 case CONTROL_NO_MBOX_UNSPOOL:
3241 no_mbox_unspool = TRUE;
3245 case CONTROL_NO_MULTILINE:
3246 no_multiline_responses = TRUE;
3249 case CONTROL_NO_PIPELINING:
3250 pipelining_enable = FALSE;
3253 case CONTROL_NO_DELAY_FLUSH:
3254 disable_delay_flush = TRUE;
3257 case CONTROL_NO_CALLOUT_FLUSH:
3258 disable_callout_flush = TRUE;
3261 case CONTROL_FAKEREJECT:
3262 cancel_cutthrough_connection("fakereject");
3263 case CONTROL_FAKEDEFER:
3264 fake_response = (control_type == CONTROL_FAKEDEFER) ? DEFER : FAIL;
3267 const uschar *pp = p + 1;
3268 while (*pp != 0) pp++;
3269 fake_response_text = expand_string(string_copyn(p+1, pp-p-1));
3274 /* Explicitly reset to default string */
3275 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).";
3279 case CONTROL_FREEZE:
3280 deliver_freeze = TRUE;
3281 deliver_frozen_at = time(NULL);
3282 freeze_tell = freeze_tell_config; /* Reset to configured value */
3283 if (Ustrncmp(p, "/no_tell", 8) == 0)
3290 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3293 cancel_cutthrough_connection("item frozen");
3296 case CONTROL_QUEUE_ONLY:
3297 queue_only_policy = TRUE;
3298 cancel_cutthrough_connection("queueing forced");
3301 case CONTROL_SUBMISSION:
3302 originator_name = US"";
3303 submission_mode = TRUE;
3306 if (Ustrncmp(p, "/sender_retain", 14) == 0)
3309 active_local_sender_retain = TRUE;
3310 active_local_from_check = FALSE;
3312 else if (Ustrncmp(p, "/domain=", 8) == 0)
3314 const uschar *pp = p + 8;
3315 while (*pp != 0 && *pp != '/') pp++;
3316 submission_domain = string_copyn(p+8, pp-p-8);
3319 /* The name= option must be last, because it swallows the rest of
3321 else if (Ustrncmp(p, "/name=", 6) == 0)
3323 const uschar *pp = p + 6;
3324 while (*pp != 0) pp++;
3325 submission_name = string_copy(parse_fix_phrase(p+6, pp-p-6,
3326 big_buffer, big_buffer_size));
3333 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3341 if (Ustrncmp(p, "/tag=", 5) == 0)
3343 const uschar *pp = p + 5;
3344 while (*pp != '\0' && *pp != '/') pp++;
3345 debug_tag = string_copyn(p+5, pp-p-5);
3348 else if (Ustrncmp(p, "/opts=", 6) == 0)
3350 const uschar *pp = p + 6;
3351 while (*pp != '\0' && *pp != '/') pp++;
3352 debug_opts = string_copyn(p+6, pp-p-6);
3356 debug_logging_activate(debug_tag, debug_opts);
3359 case CONTROL_SUPPRESS_LOCAL_FIXUPS:
3360 suppress_local_fixups = TRUE;
3363 case CONTROL_CUTTHROUGH_DELIVERY:
3364 #ifndef DISABLE_PRDR
3369 /* Too hard to think about for now. We might in future cutthrough
3370 the case where both sides handle prdr and this-node prdr acl
3372 *log_msgptr = string_sprintf("PRDR on %s reception\n", arg);
3376 *log_msgptr = US"frozen";
3377 else if (queue_only_policy)
3378 *log_msgptr = US"queue-only";
3379 else if (fake_response == FAIL)
3380 *log_msgptr = US"fakereject";
3383 if (rcpt_count == 1) cutthrough.delivery = TRUE;
3386 *log_msgptr = string_sprintf("\"control=%s\" on %s item",
3392 case CONTROL_UTF8_DOWNCONVERT:
3397 message_utf8_downconvert = 1;
3398 addr->prop.utf8_downcvt = TRUE;
3399 addr->prop.utf8_downcvt_maybe = FALSE;
3405 message_utf8_downconvert = 0;
3406 addr->prop.utf8_downcvt = FALSE;
3407 addr->prop.utf8_downcvt_maybe = FALSE;
3411 if (p[1] == '-' && p[2] == '1')
3413 message_utf8_downconvert = -1;
3414 addr->prop.utf8_downcvt = FALSE;
3415 addr->prop.utf8_downcvt_maybe = TRUE;
3419 *log_msgptr = US"bad option value for control=utf8_downconvert";
3423 message_utf8_downconvert = 1;
3424 addr->prop.utf8_downcvt = TRUE;
3425 addr->prop.utf8_downcvt_maybe = FALSE;
3435 #ifdef EXPERIMENTAL_DCC
3438 /* Seperate the regular expression and any optional parameters. */
3439 const uschar * list = arg;
3440 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
3441 /* Run the dcc backend. */
3442 rc = dcc_process(&ss);
3443 /* Modify return code based upon the existance of options. */
3444 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size)))
3445 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
3446 rc = FAIL; /* FAIL so that the message is passed to the next ACL */
3451 #ifdef WITH_CONTENT_SCAN
3453 rc = mime_decode(&arg);
3459 int delay = readconf_readtime(arg, 0, FALSE);
3462 *log_msgptr = string_sprintf("syntax error in argument for \"delay\" "
3463 "modifier: \"%s\" is not a time value", arg);
3468 HDEBUG(D_acl) debug_printf("delay modifier requests %d-second delay\n",
3473 debug_printf("delay skipped in -bh checking mode\n");
3476 /* NOTE 1: Remember that we may be
3477 dealing with stdin/stdout here, in addition to TCP/IP connections.
3478 Also, delays may be specified for non-SMTP input, where smtp_out and
3479 smtp_in will be NULL. Whatever is done must work in all cases.
3481 NOTE 2: The added feature of flushing the output before a delay must
3482 apply only to SMTP input. Hence the test for smtp_out being non-NULL.
3487 if (smtp_out != NULL && !disable_delay_flush)
3490 #if !defined(NO_POLL_H) && defined (POLLRDHUP)
3496 p.fd = fileno(smtp_out);
3497 p.events = POLLRDHUP;
3500 if (poll(&p, n, delay*1000) > 0)
3501 HDEBUG(D_acl) debug_printf("delay cancelled by peer close\n");
3504 /* It appears to be impossible to detect that a TCP/IP connection has
3505 gone away without reading from it. This means that we cannot shorten
3506 the delay below if the client goes away, because we cannot discover
3507 that the client has closed its end of the connection. (The connection
3508 is actually in a half-closed state, waiting for the server to close its
3509 end.) It would be nice to be able to detect this state, so that the
3510 Exim process is not held up unnecessarily. However, it seems that we
3511 can't. The poll() function does not do the right thing, and in any case
3512 it is not always available.
3515 while (delay > 0) delay = sleep(delay);
3522 #ifndef DISABLE_DKIM
3523 case ACLC_DKIM_SIGNER:
3524 if (dkim_cur_signer != NULL)
3525 rc = match_isinlist(dkim_cur_signer,
3526 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
3531 case ACLC_DKIM_STATUS:
3532 rc = match_isinlist(dkim_exim_expand_query(DKIM_VERIFY_STATUS),
3533 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
3537 #ifdef EXPERIMENTAL_DMARC
3538 case ACLC_DMARC_STATUS:
3539 if (!dmarc_has_been_checked)
3541 dmarc_has_been_checked = TRUE;
3542 /* used long way of dmarc_exim_expand_query() in case we need more
3543 * view into the process in the future. */
3544 rc = match_isinlist(dmarc_exim_expand_query(DMARC_VERIFY_STATUS),
3545 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
3550 rc = verify_check_dnsbl(where, &arg, log_msgptr);
3554 rc = match_isinlist(addr->domain, &arg, 0, &domainlist_anchor,
3555 addr->domain_cache, MCL_DOMAIN, TRUE, CUSS &deliver_domain_data);
3558 /* The value in tls_cipher is the full cipher name, for example,
3559 TLSv1:DES-CBC3-SHA:168, whereas the values to test for are just the
3560 cipher names such as DES-CBC3-SHA. But program defensively. We don't know
3561 what may in practice come out of the SSL library - which at the time of
3562 writing is poorly documented. */
3564 case ACLC_ENCRYPTED:
3565 if (tls_in.cipher == NULL) rc = FAIL; else
3567 uschar *endcipher = NULL;
3568 uschar *cipher = Ustrchr(tls_in.cipher, ':');
3569 if (cipher == NULL) cipher = tls_in.cipher; else
3571 endcipher = Ustrchr(++cipher, ':');
3572 if (endcipher != NULL) *endcipher = 0;
3574 rc = match_isinlist(cipher, &arg, 0, NULL, NULL, MCL_STRING, TRUE, NULL);
3575 if (endcipher != NULL) *endcipher = ':';
3579 /* Use verify_check_this_host() instead of verify_check_host() so that
3580 we can pass over &host_data to catch any looked up data. Once it has been
3581 set, it retains its value so that it's still there if another ACL verb
3582 comes through here and uses the cache. However, we must put it into
3583 permanent store in case it is also expected to be used in a subsequent
3584 message in the same SMTP connection. */
3587 rc = verify_check_this_host(&arg, sender_host_cache, NULL,
3588 (sender_host_address == NULL)? US"" : sender_host_address,
3590 if (rc == DEFER) *log_msgptr = search_error_message;
3591 if (host_data) host_data = string_copy_malloc(host_data);
3594 case ACLC_LOCAL_PARTS:
3595 rc = match_isinlist(addr->cc_local_part, &arg, 0,
3596 &localpartlist_anchor, addr->localpart_cache, MCL_LOCALPART, TRUE,
3597 CUSS &deliver_localpart_data);
3600 case ACLC_LOG_REJECT_TARGET:
3604 const uschar *s = arg;
3606 while ((ss = string_nextinlist(&s, &sep, big_buffer, big_buffer_size)))
3608 if (Ustrcmp(ss, "main") == 0) logbits |= LOG_MAIN;
3609 else if (Ustrcmp(ss, "panic") == 0) logbits |= LOG_PANIC;
3610 else if (Ustrcmp(ss, "reject") == 0) logbits |= LOG_REJECT;
3613 logbits |= LOG_MAIN|LOG_REJECT;
3614 log_write(0, LOG_MAIN|LOG_PANIC, "unknown log name \"%s\" in "
3615 "\"log_reject_target\" in %s ACL", ss, acl_wherenames[where]);
3618 log_reject_target = logbits;
3625 const uschar *s = arg;
3631 if (Ustrncmp(s, "main", 4) == 0)
3632 { logbits |= LOG_MAIN; s += 4; }
3633 else if (Ustrncmp(s, "panic", 5) == 0)
3634 { logbits |= LOG_PANIC; s += 5; }
3635 else if (Ustrncmp(s, "reject", 6) == 0)
3636 { logbits |= LOG_REJECT; s += 6; }
3639 logbits = LOG_MAIN|LOG_PANIC;
3640 s = string_sprintf(":unknown log name in \"%s\" in "
3641 "\"logwrite\" in %s ACL", arg, acl_wherenames[where]);
3647 while (isspace(*s)) s++;
3650 if (logbits == 0) logbits = LOG_MAIN;
3651 log_write(0, logbits, "%s", string_printing(s));
3655 #ifdef WITH_CONTENT_SCAN
3656 case ACLC_MALWARE: /* Run the malware backend. */
3658 /* Separate the regular expression and any optional parameters. */
3659 const uschar * list = arg;
3660 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
3662 BOOL defer_ok = FALSE;
3665 while ((opt = string_nextinlist(&list, &sep, NULL, 0)))
3666 if (strcmpic(opt, US"defer_ok") == 0)
3668 else if ( strncmpic(opt, US"tmo=", 4) == 0
3669 && (timeout = readconf_readtime(opt+4, '\0', FALSE)) < 0
3672 *log_msgptr = string_sprintf("bad timeout value in '%s'", opt);
3676 rc = malware(ss, timeout);
3677 if (rc == DEFER && defer_ok)
3678 rc = FAIL; /* FAIL so that the message is passed to the next ACL */
3682 case ACLC_MIME_REGEX:
3683 rc = mime_regex(&arg);
3688 queue_name = string_copy_malloc(arg);
3691 case ACLC_RATELIMIT:
3692 rc = acl_ratelimit(arg, where, log_msgptr);
3695 case ACLC_RECIPIENTS:
3696 rc = match_address_list((const uschar *)addr->address, TRUE, TRUE, &arg, NULL, -1, 0,
3697 CUSS &recipient_data);
3700 #ifdef WITH_CONTENT_SCAN
3706 case ACLC_REMOVE_HEADER:
3707 setup_remove_header(arg);
3710 case ACLC_SENDER_DOMAINS:
3713 sdomain = Ustrrchr(sender_address, '@');
3714 sdomain = (sdomain == NULL)? US"" : sdomain + 1;
3715 rc = match_isinlist(sdomain, &arg, 0, &domainlist_anchor,
3716 sender_domain_cache, MCL_DOMAIN, TRUE, NULL);
3721 rc = match_address_list((const uschar *)sender_address, TRUE, TRUE, &arg,
3722 sender_address_cache, -1, 0, CUSS &sender_data);
3725 /* Connection variables must persist forever */
3729 int old_pool = store_pool;
3730 if ( cb->u.varname[0] == 'c'
3731 #ifndef DISABLE_EVENT
3732 || event_name /* An event is being delivered */
3735 store_pool = POOL_PERM;
3736 acl_var_create(cb->u.varname)->data.ptr = string_copy(arg);
3737 store_pool = old_pool;
3741 #ifdef WITH_CONTENT_SCAN
3744 /* Seperate the regular expression and any optional parameters. */
3745 const uschar * list = arg;
3746 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
3747 /* Run the spam backend. */
3748 rc = spam(CUSS &ss);
3749 /* Modify return code based upon the existance of options. */
3750 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size))
3752 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
3754 /* FAIL so that the message is passed to the next ACL */
3762 #ifdef EXPERIMENTAL_SPF
3764 rc = spf_process(&arg, sender_address, SPF_PROCESS_NORMAL);
3766 case ACLC_SPF_GUESS:
3767 rc = spf_process(&arg, sender_address, SPF_PROCESS_GUESS);
3772 rc = acl_udpsend(arg, log_msgptr);
3775 /* If the verb is WARN, discard any user message from verification, because
3776 such messages are SMTP responses, not header additions. The latter come
3777 only from explicit "message" modifiers. However, put the user message into
3778 $acl_verify_message so it can be used in subsequent conditions or modifiers
3779 (until something changes it). */
3782 rc = acl_verify(where, addr, arg, user_msgptr, log_msgptr, basic_errno);
3784 acl_verify_message = *user_msgptr;
3785 if (verb == ACL_WARN) *user_msgptr = NULL;
3789 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown "
3790 "condition %d", cb->type);
3794 /* If a condition was negated, invert OK/FAIL. */
3796 if (!cond_modifiers[cb->type] && cb->u.negated)
3798 if (rc == OK) rc = FAIL;
3799 else if (rc == FAIL || rc == FAIL_DROP) rc = OK;
3802 if (rc != OK) break; /* Conditions loop */
3806 /* If the result is the one for which "message" and/or "log_message" are used,
3807 handle the values of these modifiers. If there isn't a log message set, we make
3808 it the same as the user message.
3810 "message" is a user message that will be included in an SMTP response. Unless
3811 it is empty, it overrides any previously set user message.
3813 "log_message" is a non-user message, and it adds to any existing non-user
3814 message that is already set.
3816 Most verbs have but a single return for which the messages are relevant, but
3817 for "discard", it's useful to have the log message both when it succeeds and
3818 when it fails. For "accept", the message is used in the OK case if there is no
3819 "endpass", but (for backwards compatibility) in the FAIL case if "endpass" is
3822 if (*epp && rc == OK) user_message = NULL;
3824 if (((1<<rc) & msgcond[verb]) != 0)
3827 uschar *old_user_msgptr = *user_msgptr;
3828 uschar *old_log_msgptr = (*log_msgptr != NULL)? *log_msgptr : old_user_msgptr;
3830 /* If the verb is "warn", messages generated by conditions (verification or
3831 nested ACLs) are always discarded. This also happens for acceptance verbs
3832 when they actually do accept. Only messages specified at this level are used.
3833 However, the value of an existing message is available in $acl_verify_message
3834 during expansions. */
3836 if (verb == ACL_WARN ||
3837 (rc == OK && (verb == ACL_ACCEPT || verb == ACL_DISCARD)))
3838 *log_msgptr = *user_msgptr = NULL;
3840 if (user_message != NULL)
3842 acl_verify_message = old_user_msgptr;
3843 expmessage = expand_string(user_message);
3844 if (expmessage == NULL)
3846 if (!expand_string_forcedfail)
3847 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
3848 user_message, expand_string_message);
3850 else if (expmessage[0] != 0) *user_msgptr = expmessage;
3853 if (log_message != NULL)
3855 acl_verify_message = old_log_msgptr;
3856 expmessage = expand_string(log_message);
3857 if (expmessage == NULL)
3859 if (!expand_string_forcedfail)
3860 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
3861 log_message, expand_string_message);
3863 else if (expmessage[0] != 0)
3865 *log_msgptr = (*log_msgptr == NULL)? expmessage :
3866 string_sprintf("%s: %s", expmessage, *log_msgptr);
3870 /* If no log message, default it to the user message */
3872 if (*log_msgptr == NULL) *log_msgptr = *user_msgptr;
3875 acl_verify_message = NULL;
3883 /*************************************************
3884 * Get line from a literal ACL *
3885 *************************************************/
3887 /* This function is passed to acl_read() in order to extract individual lines
3888 of a literal ACL, which we access via static pointers. We can destroy the
3889 contents because this is called only once (the compiled ACL is remembered).
3891 This code is intended to treat the data in the same way as lines in the main
3892 Exim configuration file. That is:
3894 . Leading spaces are ignored.
3896 . A \ at the end of a line is a continuation - trailing spaces after the \
3897 are permitted (this is because I don't believe in making invisible things
3898 significant). Leading spaces on the continued part of a line are ignored.
3900 . Physical lines starting (significantly) with # are totally ignored, and
3901 may appear within a sequence of backslash-continued lines.
3903 . Blank lines are ignored, but will end a sequence of continuations.
3906 Returns: a pointer to the next line
3910 static uschar *acl_text; /* Current pointer in the text */
3911 static uschar *acl_text_end; /* Points one past the terminating '0' */
3919 /* This loop handles leading blank lines and comments. */
3923 while (isspace(*acl_text)) acl_text++; /* Leading spaces/empty lines */
3924 if (*acl_text == 0) return NULL; /* No more data */
3925 yield = acl_text; /* Potential data line */
3927 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3929 /* If we hit the end before a newline, we have the whole logical line. If
3930 it's a comment, there's no more data to be given. Otherwise, yield it. */
3932 if (*acl_text == 0) return (*yield == '#')? NULL : yield;
3934 /* After reaching a newline, end this loop if the physical line does not
3935 start with '#'. If it does, it's a comment, and the loop continues. */
3937 if (*yield != '#') break;
3940 /* This loop handles continuations. We know we have some real data, ending in
3941 newline. See if there is a continuation marker at the end (ignoring trailing
3942 white space). We know that *yield is not white space, so no need to test for
3943 cont > yield in the backwards scanning loop. */
3948 for (cont = acl_text - 1; isspace(*cont); cont--);
3950 /* If no continuation follows, we are done. Mark the end of the line and
3959 /* We have encountered a continuation. Skip over whitespace at the start of
3960 the next line, and indeed the whole of the next line or lines if they are
3965 while (*(++acl_text) == ' ' || *acl_text == '\t');
3966 if (*acl_text != '#') break;
3967 while (*(++acl_text) != 0 && *acl_text != '\n');
3970 /* We have the start of a continuation line. Move all the rest of the data
3971 to join onto the previous line, and then find its end. If the end is not a
3972 newline, we are done. Otherwise loop to look for another continuation. */
3974 memmove(cont, acl_text, acl_text_end - acl_text);
3975 acl_text_end -= acl_text - cont;
3977 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3978 if (*acl_text == 0) return yield;
3981 /* Control does not reach here */
3988 /*************************************************
3989 * Check access using an ACL *
3990 *************************************************/
3992 /* This function is called from address_check. It may recurse via
3993 acl_check_condition() - hence the use of a level to stop looping. The ACL is
3994 passed as a string which is expanded. A forced failure implies no access check
3995 is required. If the result is a single word, it is taken as the name of an ACL
3996 which is sought in the global ACL tree. Otherwise, it is taken as literal ACL
3997 text, complete with newlines, and parsed as such. In both cases, the ACL check
3998 is then run. This function uses an auxiliary function for acl_read() to call
3999 for reading individual lines of a literal ACL. This is acl_getline(), which
4000 appears immediately above.
4003 where where called from
4004 addr address item when called from RCPT; otherwise NULL
4005 s the input string; NULL is the same as an empty ACL => DENY
4006 level the nesting level
4007 user_msgptr where to put a user error (for SMTP response)
4008 log_msgptr where to put a logging message (not for SMTP response)
4010 Returns: OK access is granted
4011 DISCARD access is apparently granted...
4012 FAIL access is denied
4013 FAIL_DROP access is denied; drop the connection
4014 DEFER can't tell at the moment
4019 acl_check_internal(int where, address_item *addr, uschar *s, int level,
4020 uschar **user_msgptr, uschar **log_msgptr)
4023 acl_block *acl = NULL;
4024 uschar *acl_name = US"inline ACL";
4027 /* Catch configuration loops */
4031 *log_msgptr = US"ACL nested too deep: possible loop";
4037 HDEBUG(D_acl) debug_printf("ACL is NULL: implicit DENY\n");
4041 /* At top level, we expand the incoming string. At lower levels, it has already
4042 been expanded as part of condition processing. */
4046 ss = expand_string(s);
4049 if (expand_string_forcedfail) return OK;
4050 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s", s,
4051 expand_string_message);
4057 while (isspace(*ss))ss++;
4059 /* If we can't find a named ACL, the default is to parse it as an inline one.
4060 (Unless it begins with a slash; non-existent files give rise to an error.) */
4064 /* Handle the case of a string that does not contain any spaces. Look for a
4065 named ACL among those read from the configuration, or a previously read file.
4066 It is possible that the pointer to the ACL is NULL if the configuration
4067 contains a name with no data. If not found, and the text begins with '/',
4068 read an ACL from a file, and save it so it can be re-used. */
4070 if (Ustrchr(ss, ' ') == NULL)
4072 tree_node *t = tree_search(acl_anchor, ss);
4075 acl = (acl_block *)(t->data.ptr);
4078 HDEBUG(D_acl) debug_printf("ACL \"%s\" is empty: implicit DENY\n", ss);
4081 acl_name = string_sprintf("ACL \"%s\"", ss);
4082 HDEBUG(D_acl) debug_printf("using ACL \"%s\"\n", ss);
4085 else if (*ss == '/')
4087 struct stat statbuf;
4088 fd = Uopen(ss, O_RDONLY, 0);
4091 *log_msgptr = string_sprintf("failed to open ACL file \"%s\": %s", ss,
4096 if (fstat(fd, &statbuf) != 0)
4098 *log_msgptr = string_sprintf("failed to fstat ACL file \"%s\": %s", ss,
4103 acl_text = store_get(statbuf.st_size + 1);
4104 acl_text_end = acl_text + statbuf.st_size + 1;
4106 if (read(fd, acl_text, statbuf.st_size) != statbuf.st_size)
4108 *log_msgptr = string_sprintf("failed to read ACL file \"%s\": %s",
4109 ss, strerror(errno));
4112 acl_text[statbuf.st_size] = 0;
4115 acl_name = string_sprintf("ACL \"%s\"", ss);
4116 HDEBUG(D_acl) debug_printf("read ACL from file %s\n", ss);
4120 /* Parse an ACL that is still in text form. If it came from a file, remember it
4121 in the ACL tree, having read it into the POOL_PERM store pool so that it
4122 persists between multiple messages. */
4126 int old_pool = store_pool;
4127 if (fd >= 0) store_pool = POOL_PERM;
4128 acl = acl_read(acl_getline, log_msgptr);
4129 store_pool = old_pool;
4130 if (acl == NULL && *log_msgptr != NULL) return ERROR;
4133 tree_node *t = store_get_perm(sizeof(tree_node) + Ustrlen(ss));
4134 Ustrcpy(t->name, ss);
4136 (void)tree_insertnode(&acl_anchor, t);
4140 /* Now we have an ACL to use. It's possible it may be NULL. */
4145 int basic_errno = 0;
4146 BOOL endpass_seen = FALSE;
4147 BOOL acl_quit_check = level == 0
4148 && (where == ACL_WHERE_QUIT || where == ACL_WHERE_NOTQUIT);
4150 *log_msgptr = *user_msgptr = NULL;
4151 acl_temp_details = FALSE;
4153 HDEBUG(D_acl) debug_printf("processing \"%s\"\n", verbs[acl->verb]);
4155 /* Clear out any search error message from a previous check before testing
4158 search_error_message = NULL;
4159 cond = acl_check_condition(acl->verb, acl->condition, where, addr, level,
4160 &endpass_seen, user_msgptr, log_msgptr, &basic_errno);
4162 /* Handle special returns: DEFER causes a return except on a WARN verb;
4163 ERROR always causes a return. */
4168 HDEBUG(D_acl) debug_printf("%s: condition test deferred in %s\n", verbs[acl->verb], acl_name);
4169 if (basic_errno != ERRNO_CALLOUTDEFER)
4171 if (search_error_message != NULL && *search_error_message != 0)
4172 *log_msgptr = search_error_message;
4173 if (smtp_return_error_details) acl_temp_details = TRUE;
4177 acl_temp_details = TRUE;
4179 if (acl->verb != ACL_WARN) return DEFER;
4182 default: /* Paranoia */
4184 HDEBUG(D_acl) debug_printf("%s: condition test error in %s\n", verbs[acl->verb], acl_name);
4188 HDEBUG(D_acl) debug_printf("%s: condition test succeeded in %s\n",
4189 verbs[acl->verb], acl_name);
4193 HDEBUG(D_acl) debug_printf("%s: condition test failed in %s\n", verbs[acl->verb], acl_name);
4196 /* DISCARD and DROP can happen only from a nested ACL condition, and
4197 DISCARD can happen only for an "accept" or "discard" verb. */
4200 HDEBUG(D_acl) debug_printf("%s: condition test yielded \"discard\" in %s\n",
4201 verbs[acl->verb], acl_name);
4205 HDEBUG(D_acl) debug_printf("%s: condition test yielded \"drop\" in %s\n",
4206 verbs[acl->verb], acl_name);
4210 /* At this point, cond for most verbs is either OK or FAIL or (as a result of
4211 a nested ACL condition) FAIL_DROP. However, for WARN, cond may be DEFER, and
4212 for ACCEPT and DISCARD, it may be DISCARD after a nested ACL call. */
4217 if (cond == OK || cond == DISCARD)
4219 HDEBUG(D_acl) debug_printf("end of %s: ACCEPT\n", acl_name);
4224 HDEBUG(D_acl) debug_printf("accept: endpass encountered - denying access\n");
4232 HDEBUG(D_acl) debug_printf("end of %s: DEFER\n", acl_name);
4233 if (acl_quit_check) goto badquit;
4234 acl_temp_details = TRUE;
4242 HDEBUG(D_acl) debug_printf("end of %s: DENY\n", acl_name);
4243 if (acl_quit_check) goto badquit;
4249 if (cond == OK || cond == DISCARD)
4251 HDEBUG(D_acl) debug_printf("end of %s: DISCARD\n", acl_name);
4252 if (acl_quit_check) goto badquit;
4257 HDEBUG(D_acl) debug_printf("discard: endpass encountered - denying access\n");
4265 HDEBUG(D_acl) debug_printf("end of %s: DROP\n", acl_name);
4266 if (acl_quit_check) goto badquit;
4274 HDEBUG(D_acl) debug_printf("end of %s: not OK\n", acl_name);
4275 if (acl_quit_check) goto badquit;
4282 acl_warn(where, *user_msgptr, *log_msgptr);
4283 else if (cond == DEFER && LOGGING(acl_warn_skipped))
4284 log_write(0, LOG_MAIN, "%s Warning: ACL \"warn\" statement skipped: "
4285 "condition test deferred%s%s", host_and_ident(TRUE),
4286 (*log_msgptr == NULL)? US"" : US": ",
4287 (*log_msgptr == NULL)? US"" : *log_msgptr);
4288 *log_msgptr = *user_msgptr = NULL; /* In case implicit DENY follows */
4292 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown verb %d",
4297 /* Pass to the next ACL item */
4302 /* We have reached the end of the ACL. This is an implicit DENY. */
4304 HDEBUG(D_acl) debug_printf("end of %s: implicit DENY\n", acl_name);
4308 *log_msgptr = string_sprintf("QUIT or not-QUIT teplevel ACL may not fail "
4309 "('%s' verb used incorrectly)", verbs[acl->verb]);
4316 /* Same args as acl_check_internal() above, but the string s is
4317 the name of an ACL followed optionally by up to 9 space-separated arguments.
4318 The name and args are separately expanded. Args go into $acl_arg globals. */
4320 acl_check_wargs(int where, address_item *addr, const uschar *s, int level,
4321 uschar **user_msgptr, uschar **log_msgptr)
4324 uschar * tmp_arg[9]; /* must match acl_arg[] */
4325 uschar * sav_arg[9]; /* must match acl_arg[] */
4331 if (!(tmp = string_dequote(&s)) || !(name = expand_string(tmp)))
4334 for (i = 0; i < 9; i++)
4336 while (*s && isspace(*s)) s++;
4338 if (!(tmp = string_dequote(&s)) || !(tmp_arg[i] = expand_string(tmp)))
4345 sav_narg = acl_narg;
4347 for (i = 0; i < acl_narg; i++)
4349 sav_arg[i] = acl_arg[i];
4350 acl_arg[i] = tmp_arg[i];
4354 sav_arg[i] = acl_arg[i];
4355 acl_arg[i++] = NULL;
4358 ret = acl_check_internal(where, addr, name, level, user_msgptr, log_msgptr);
4360 acl_narg = sav_narg;
4361 for (i = 0; i < 9; i++) acl_arg[i] = sav_arg[i];
4365 if (expand_string_forcedfail) return ERROR;
4366 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s",
4367 tmp, expand_string_message);
4368 return search_find_defer?DEFER:ERROR;
4373 /*************************************************
4374 * Check access using an ACL *
4375 *************************************************/
4377 /* Alternate interface for ACL, used by expansions */
4379 acl_eval(int where, uschar *s, uschar **user_msgptr, uschar **log_msgptr)
4382 address_item *addr = NULL;
4384 *user_msgptr = *log_msgptr = NULL;
4385 sender_verified_failed = NULL;
4386 ratelimiters_cmd = NULL;
4387 log_reject_target = LOG_MAIN|LOG_REJECT;
4389 if (where == ACL_WHERE_RCPT)
4391 adb = address_defaults;
4393 addr->address = expand_string(US"$local_part@$domain");
4394 addr->domain = deliver_domain;
4395 addr->local_part = deliver_localpart;
4396 addr->cc_local_part = deliver_localpart;
4397 addr->lc_local_part = deliver_localpart;
4400 return acl_check_internal(where, addr, s, 0, user_msgptr, log_msgptr);
4405 /* This is the external interface for ACL checks. It sets up an address and the
4406 expansions for $domain and $local_part when called after RCPT, then calls
4407 acl_check_internal() to do the actual work.
4410 where ACL_WHERE_xxxx indicating where called from
4411 recipient RCPT address for RCPT check, else NULL
4412 s the input string; NULL is the same as an empty ACL => DENY
4413 user_msgptr where to put a user error (for SMTP response)
4414 log_msgptr where to put a logging message (not for SMTP response)
4416 Returns: OK access is granted by an ACCEPT verb
4417 DISCARD access is granted by a DISCARD verb
4418 FAIL access is denied
4419 FAIL_DROP access is denied; drop the connection
4420 DEFER can't tell at the moment
4423 int acl_where = ACL_WHERE_UNKNOWN;
4426 acl_check(int where, uschar *recipient, uschar *s, uschar **user_msgptr,
4427 uschar **log_msgptr)
4431 address_item *addr = NULL;
4433 *user_msgptr = *log_msgptr = NULL;
4434 sender_verified_failed = NULL;
4435 ratelimiters_cmd = NULL;
4436 log_reject_target = LOG_MAIN|LOG_REJECT;
4438 #ifndef DISABLE_PRDR
4439 if (where==ACL_WHERE_RCPT || where==ACL_WHERE_VRFY || where==ACL_WHERE_PRDR)
4441 if (where==ACL_WHERE_RCPT || where==ACL_WHERE_VRFY)
4444 adb = address_defaults;
4446 addr->address = recipient;
4447 if (deliver_split_address(addr) == DEFER)
4449 *log_msgptr = US"defer in percent_hack_domains check";
4453 if ((addr->prop.utf8_msg = message_smtputf8))
4455 addr->prop.utf8_downcvt = message_utf8_downconvert == 1;
4456 addr->prop.utf8_downcvt_maybe = message_utf8_downconvert == -1;
4459 deliver_domain = addr->domain;
4460 deliver_localpart = addr->local_part;
4464 rc = acl_check_internal(where, addr, s, 0, user_msgptr, log_msgptr);
4465 acl_where = ACL_WHERE_UNKNOWN;
4467 /* Cutthrough - if requested,
4468 and WHERE_RCPT and not yet opened conn as result of recipient-verify,
4469 and rcpt acl returned accept,
4470 and first recipient (cancel on any subsequents)
4471 open one now and run it up to RCPT acceptance.
4472 A failed verify should cancel cutthrough request,
4473 and will pass the fail to the originator.
4474 Initial implementation: dual-write to spool.
4475 Assume the rxd datastream is now being copied byte-for-byte to an open cutthrough connection.
4477 Cease cutthrough copy on rxd final dot; do not send one.
4479 On a data acl, if not accept and a cutthrough conn is open, hard-close it (no SMTP niceness).
4481 On data acl accept, terminate the dataphase on an open cutthrough conn. If accepted or
4482 perm-rejected, reflect that to the original sender - and dump the spooled copy.
4483 If temp-reject, close the conn (and keep the spooled copy).
4484 If conn-failure, no action (and keep the spooled copy).
4488 case ACL_WHERE_RCPT:
4489 #ifndef DISABLE_PRDR
4490 case ACL_WHERE_PRDR:
4492 if (host_checking_callout) /* -bhc mode */
4493 cancel_cutthrough_connection("host-checking mode");
4494 else if (rc == OK && cutthrough.delivery && rcpt_count > cutthrough.nrcpt)
4495 rc = open_cutthrough_connection(addr);
4498 case ACL_WHERE_PREDATA:
4500 cutthrough_predata();
4502 cancel_cutthrough_connection("predata acl not ok");
4505 case ACL_WHERE_QUIT:
4506 case ACL_WHERE_NOTQUIT:
4507 cancel_cutthrough_connection("quit or notquit");
4514 deliver_domain = deliver_localpart = deliver_address_data =
4515 sender_address_data = NULL;
4517 /* A DISCARD response is permitted only for message ACLs, excluding the PREDATA
4518 ACL, which is really in the middle of an SMTP command. */
4522 if (where > ACL_WHERE_NOTSMTP || where == ACL_WHERE_PREDATA)
4524 log_write(0, LOG_MAIN|LOG_PANIC, "\"discard\" verb not allowed in %s "
4525 "ACL", acl_wherenames[where]);
4531 /* A DROP response is not permitted from MAILAUTH */
4533 if (rc == FAIL_DROP && where == ACL_WHERE_MAILAUTH)
4535 log_write(0, LOG_MAIN|LOG_PANIC, "\"drop\" verb not allowed in %s "
4536 "ACL", acl_wherenames[where]);
4540 /* Before giving a response, take a look at the length of any user message, and
4541 split it up into multiple lines if possible. */
4543 *user_msgptr = string_split_message(*user_msgptr);
4544 if (fake_response != OK)
4545 fake_response_text = string_split_message(fake_response_text);
4551 /*************************************************
4552 * Create ACL variable *
4553 *************************************************/
4555 /* Create an ACL variable or reuse an existing one. ACL variables are in a
4556 binary tree (see tree.c) with acl_var_c and acl_var_m as root nodes.
4559 name pointer to the variable's name, starting with c or m
4561 Returns the pointer to variable's tree node
4565 acl_var_create(uschar *name)
4567 tree_node *node, **root;
4568 root = (name[0] == 'c')? &acl_var_c : &acl_var_m;
4569 node = tree_search(*root, name);
4572 node = store_get(sizeof(tree_node) + Ustrlen(name));
4573 Ustrcpy(node->name, name);
4574 (void)tree_insertnode(root, node);
4576 node->data.ptr = NULL;
4582 /*************************************************
4583 * Write an ACL variable in spool format *
4584 *************************************************/
4586 /* This function is used as a callback for tree_walk when writing variables to
4587 the spool file. To retain spool file compatibility, what is written is -aclc or
4588 -aclm followed by the rest of the name and the data length, space separated,
4589 then the value itself, starting on a new line, and terminated by an additional
4590 newline. When we had only numbered ACL variables, the first line might look
4591 like this: "-aclc 5 20". Now it might be "-aclc foo 20" for the variable called
4595 name of the variable
4596 value of the variable
4597 ctx FILE pointer (as a void pointer)
4603 acl_var_write(uschar *name, uschar *value, void *ctx)
4605 FILE *f = (FILE *)ctx;
4606 fprintf(f, "-acl%c %s %d\n%s\n", name[0], name+1, Ustrlen(value), value);