1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2014 */
6 /* See the file NOTICE for conditions of use and distribution. */
8 /* Code for handling Access Control Lists (ACLs) */
13 /* Default callout timeout */
15 #define CALLOUT_TIMEOUT_DEFAULT 30
17 /* ACL verb codes - keep in step with the table of verbs that follows */
19 enum { ACL_ACCEPT, ACL_DEFER, ACL_DENY, ACL_DISCARD, ACL_DROP, ACL_REQUIRE,
24 static uschar *verbs[] = {
33 /* For each verb, the conditions for which "message" or "log_message" are used
34 are held as a bitmap. This is to avoid expanding the strings unnecessarily. For
35 "accept", the FAIL case is used only after "endpass", but that is selected in
38 static int msgcond[] = {
39 (1<<OK) | (1<<FAIL) | (1<<FAIL_DROP), /* accept */
42 (1<<OK) | (1<<FAIL) | (1<<FAIL_DROP), /* discard */
44 (1<<FAIL) | (1<<FAIL_DROP), /* require */
48 /* ACL condition and modifier codes - keep in step with the table that
49 follows, and the cond_expand_at_top and uschar cond_modifiers tables lower
55 #ifdef EXPERIMENTAL_BRIGHTMAIL
61 #ifdef EXPERIMENTAL_DCC
64 #ifdef WITH_CONTENT_SCAN
68 #ifdef WITH_OLD_DEMIME
75 #ifdef EXPERIMENTAL_DMARC
85 ACLC_LOG_REJECT_TARGET,
87 #ifdef WITH_CONTENT_SCAN
91 #ifdef WITH_CONTENT_SCAN
96 #ifdef WITH_CONTENT_SCAN
103 #ifdef WITH_CONTENT_SCAN
106 #ifdef EXPERIMENTAL_SPF
113 /* ACL conditions/modifiers: "delay", "control", "continue", "endpass",
114 "message", "log_message", "log_reject_target", "logwrite", and "set" are
115 modifiers that look like conditions but always return TRUE. They are used for
116 their side effects. */
118 static uschar *conditions[] = {
122 #ifdef EXPERIMENTAL_BRIGHTMAIL
128 #ifdef EXPERIMENTAL_DCC
131 #ifdef WITH_CONTENT_SCAN
135 #ifdef WITH_OLD_DEMIME
142 #ifdef EXPERIMENTAL_DMARC
152 US"log_reject_target",
154 #ifdef WITH_CONTENT_SCAN
158 #ifdef WITH_CONTENT_SCAN
163 #ifdef WITH_CONTENT_SCAN
167 US"sender_domains", US"senders", US"set",
168 #ifdef WITH_CONTENT_SCAN
171 #ifdef EXPERIMENTAL_SPF
179 /* Return values from decode_control(); keep in step with the table of names
183 CONTROL_AUTH_UNADVERTISED,
184 #ifdef EXPERIMENTAL_BRIGHTMAIL
191 #ifdef EXPERIMENTAL_DMARC
192 CONTROL_DMARC_VERIFY,
193 CONTROL_DMARC_FORENSIC,
197 CONTROL_CASEFUL_LOCAL_PART,
198 CONTROL_CASELOWER_LOCAL_PART,
199 CONTROL_CUTTHROUGH_DELIVERY,
200 CONTROL_ENFORCE_SYNC,
201 CONTROL_NO_ENFORCE_SYNC,
205 CONTROL_SUPPRESS_LOCAL_FIXUPS,
206 #ifdef WITH_CONTENT_SCAN
207 CONTROL_NO_MBOX_UNSPOOL,
211 CONTROL_NO_MULTILINE,
212 CONTROL_NO_PIPELINING,
213 CONTROL_NO_DELAY_FLUSH,
214 CONTROL_NO_CALLOUT_FLUSH
217 /* ACL control names; keep in step with the table above! This list is used for
218 turning ids into names. The actual list of recognized names is in the variable
219 control_def controls_list[] below. The fact that there are two lists is a mess
220 and should be tidied up. */
222 static uschar *controls[] = {
223 US"allow_auth_unadvertised",
224 #ifdef EXPERIMENTAL_BRIGHTMAIL
229 US"dkim_disable_verify",
231 #ifdef EXPERIMENTAL_DMARC
232 US"dmarc_disable_verify",
233 US"dmarc_enable_forensic",
237 US"caseful_local_part",
238 US"caselower_local_part",
239 US"cutthrough_delivery",
245 US"suppress_local_fixups",
246 #ifdef WITH_CONTENT_SCAN
251 US"no_multiline_responses",
257 /* Flags to indicate for which conditions/modifiers a string expansion is done
258 at the outer level. In the other cases, expansion already occurs in the
259 checking functions. */
261 static uschar cond_expand_at_top[] = {
263 TRUE, /* add_header */
264 FALSE, /* authenticated */
265 #ifdef EXPERIMENTAL_BRIGHTMAIL
266 TRUE, /* bmi_optin */
268 TRUE, /* condition */
271 #ifdef EXPERIMENTAL_DCC
274 #ifdef WITH_CONTENT_SCAN
278 #ifdef WITH_OLD_DEMIME
282 TRUE, /* dkim_signers */
283 TRUE, /* dkim_status */
285 #ifdef EXPERIMENTAL_DMARC
286 TRUE, /* dmarc_status */
290 FALSE, /* encrypted */
293 FALSE, /* local_parts */
294 TRUE, /* log_message */
295 TRUE, /* log_reject_target */
297 #ifdef WITH_CONTENT_SCAN
301 #ifdef WITH_CONTENT_SCAN
302 TRUE, /* mime_regex */
304 TRUE, /* ratelimit */
305 FALSE, /* recipients */
306 #ifdef WITH_CONTENT_SCAN
309 TRUE, /* remove_header */
310 FALSE, /* sender_domains */
313 #ifdef WITH_CONTENT_SCAN
316 #ifdef EXPERIMENTAL_SPF
318 TRUE, /* spf_guess */
324 /* Flags to identify the modifiers */
326 static uschar cond_modifiers[] = {
328 TRUE, /* add_header */
329 FALSE, /* authenticated */
330 #ifdef EXPERIMENTAL_BRIGHTMAIL
331 TRUE, /* bmi_optin */
333 FALSE, /* condition */
336 #ifdef EXPERIMENTAL_DCC
339 #ifdef WITH_CONTENT_SCAN
343 #ifdef WITH_OLD_DEMIME
347 FALSE, /* dkim_signers */
348 FALSE, /* dkim_status */
350 #ifdef EXPERIMENTAL_DMARC
351 FALSE, /* dmarc_status */
353 FALSE, /* dnslists */
355 FALSE, /* encrypted */
358 FALSE, /* local_parts */
359 TRUE, /* log_message */
360 TRUE, /* log_reject_target */
362 #ifdef WITH_CONTENT_SCAN
366 #ifdef WITH_CONTENT_SCAN
367 FALSE, /* mime_regex */
369 FALSE, /* ratelimit */
370 FALSE, /* recipients */
371 #ifdef WITH_CONTENT_SCAN
374 TRUE, /* remove_header */
375 FALSE, /* sender_domains */
378 #ifdef WITH_CONTENT_SCAN
381 #ifdef EXPERIMENTAL_SPF
383 FALSE, /* spf_guess */
389 /* Bit map vector of which conditions and modifiers are not allowed at certain
390 times. For each condition and modifier, there's a bitmap of dis-allowed times.
391 For some, it is easier to specify the negation of a small number of allowed
394 static unsigned int cond_forbids[] = {
398 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* add_header */
399 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
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 */
450 #ifdef WITH_OLD_DEMIME
452 ~((1<<ACL_WHERE_DATA)| /* demime */
456 (1<<ACL_WHERE_NOTSMTP)),
461 ~(1<<ACL_WHERE_DKIM), /* dkim_signers */
464 ~(1<<ACL_WHERE_DKIM), /* dkim_status */
467 #ifdef EXPERIMENTAL_DMARC
469 ~(1<<ACL_WHERE_DATA), /* dmarc_status */
472 (1<<ACL_WHERE_NOTSMTP)| /* dnslists */
473 (1<<ACL_WHERE_NOTSMTP_START),
476 ~((1<<ACL_WHERE_RCPT) /* domains */
482 (1<<ACL_WHERE_NOTSMTP)| /* encrypted */
483 (1<<ACL_WHERE_CONNECT)|
484 (1<<ACL_WHERE_NOTSMTP_START)|
489 (1<<ACL_WHERE_NOTSMTP)| /* hosts */
490 (1<<ACL_WHERE_NOTSMTP_START),
493 ~((1<<ACL_WHERE_RCPT) /* local_parts */
501 0, /* log_reject_target */
505 #ifdef WITH_CONTENT_SCAN
507 ~((1<<ACL_WHERE_DATA)| /* malware */
511 (1<<ACL_WHERE_NOTSMTP)),
516 #ifdef WITH_CONTENT_SCAN
518 ~(1<<ACL_WHERE_MIME), /* mime_regex */
524 ~(1<<ACL_WHERE_RCPT), /* recipients */
526 #ifdef WITH_CONTENT_SCAN
528 ~((1<<ACL_WHERE_DATA)| /* regex */
532 (1<<ACL_WHERE_NOTSMTP)|
533 (1<<ACL_WHERE_MIME)),
537 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* remove_header */
538 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
542 (1<<ACL_WHERE_MIME)|(1<<ACL_WHERE_NOTSMTP)|
543 (1<<ACL_WHERE_NOTSMTP_START)),
545 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* sender_domains */
547 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
548 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
549 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
551 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* senders */
553 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
554 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
555 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
559 #ifdef WITH_CONTENT_SCAN
561 ~((1<<ACL_WHERE_DATA)| /* spam */
565 (1<<ACL_WHERE_NOTSMTP)),
568 #ifdef EXPERIMENTAL_SPF
569 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* spf */
571 (1<<ACL_WHERE_MAILAUTH)|
572 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
573 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY)|
574 (1<<ACL_WHERE_NOTSMTP)|
575 (1<<ACL_WHERE_NOTSMTP_START),
577 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* spf_guess */
579 (1<<ACL_WHERE_MAILAUTH)|
580 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
581 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY)|
582 (1<<ACL_WHERE_NOTSMTP)|
583 (1<<ACL_WHERE_NOTSMTP_START),
588 /* Certain types of verify are always allowed, so we let it through
589 always and check in the verify function itself */
595 /* Bit map vector of which controls are not allowed at certain times. For
596 each control, there's a bitmap of dis-allowed times. For some, it is easier to
597 specify the negation of a small number of allowed times. */
599 static unsigned int control_forbids[] = {
601 ~((1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)), /* allow_auth_unadvertised */
603 #ifdef EXPERIMENTAL_BRIGHTMAIL
610 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* dkim_disable_verify */
614 (1<<ACL_WHERE_NOTSMTP_START),
617 #ifdef EXPERIMENTAL_DMARC
618 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* dmarc_disable_verify */
619 (1<<ACL_WHERE_NOTSMTP_START),
620 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* dmarc_enable_forensic */
621 (1<<ACL_WHERE_NOTSMTP_START),
624 (1<<ACL_WHERE_NOTSMTP)|
625 (1<<ACL_WHERE_NOTSMTP_START)|
626 (1<<ACL_WHERE_NOTQUIT), /* dscp */
631 ~(1<<ACL_WHERE_RCPT), /* caseful_local_part */
634 ~(1<<ACL_WHERE_RCPT), /* caselower_local_part */
637 0, /* cutthrough_delivery */
639 (1<<ACL_WHERE_NOTSMTP)| /* enforce_sync */
640 (1<<ACL_WHERE_NOTSMTP_START),
642 (1<<ACL_WHERE_NOTSMTP)| /* no_enforce_sync */
643 (1<<ACL_WHERE_NOTSMTP_START),
646 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* freeze */
647 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
648 // (1<<ACL_WHERE_PRDR)| /* Not allow one user to freeze for all */
649 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)),
652 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* queue_only */
653 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
654 // (1<<ACL_WHERE_PRDR)| /* Not allow one user to freeze for all */
655 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)),
658 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* submission */
659 (1<<ACL_WHERE_PREDATA)),
662 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* suppress_local_fixups */
663 (1<<ACL_WHERE_PREDATA)|
664 (1<<ACL_WHERE_NOTSMTP_START)),
666 #ifdef WITH_CONTENT_SCAN
668 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* no_mbox_unspool */
669 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
670 // (1<<ACL_WHERE_PRDR)| /* Not allow one user to freeze for all */
671 (1<<ACL_WHERE_MIME)),
675 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakedefer */
676 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
680 (1<<ACL_WHERE_MIME)),
683 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakereject */
684 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
688 (1<<ACL_WHERE_MIME)),
690 (1<<ACL_WHERE_NOTSMTP)| /* no_multiline */
691 (1<<ACL_WHERE_NOTSMTP_START),
693 (1<<ACL_WHERE_NOTSMTP)| /* no_pipelining */
694 (1<<ACL_WHERE_NOTSMTP_START),
696 (1<<ACL_WHERE_NOTSMTP)| /* no_delay_flush */
697 (1<<ACL_WHERE_NOTSMTP_START),
699 (1<<ACL_WHERE_NOTSMTP)| /* no_callout_flush */
700 (1<<ACL_WHERE_NOTSMTP_START)
703 /* Structure listing various control arguments, with their characteristics. */
705 typedef struct control_def {
707 int value; /* CONTROL_xxx value */
708 BOOL has_option; /* Has /option(s) following */
711 static control_def controls_list[] = {
712 { US"allow_auth_unadvertised", CONTROL_AUTH_UNADVERTISED, FALSE },
713 #ifdef EXPERIMENTAL_BRIGHTMAIL
714 { US"bmi_run", CONTROL_BMI_RUN, FALSE },
716 { US"debug", CONTROL_DEBUG, TRUE },
718 { US"dkim_disable_verify", CONTROL_DKIM_VERIFY, FALSE },
720 #ifdef EXPERIMENTAL_DMARC
721 { US"dmarc_disable_verify", CONTROL_DMARC_VERIFY, FALSE },
722 { US"dmarc_enable_forensic", CONTROL_DMARC_FORENSIC, FALSE },
724 { US"dscp", CONTROL_DSCP, TRUE },
725 { US"caseful_local_part", CONTROL_CASEFUL_LOCAL_PART, FALSE },
726 { US"caselower_local_part", CONTROL_CASELOWER_LOCAL_PART, FALSE },
727 { US"enforce_sync", CONTROL_ENFORCE_SYNC, FALSE },
728 { US"freeze", CONTROL_FREEZE, TRUE },
729 { US"no_callout_flush", CONTROL_NO_CALLOUT_FLUSH, FALSE },
730 { US"no_delay_flush", CONTROL_NO_DELAY_FLUSH, FALSE },
731 { US"no_enforce_sync", CONTROL_NO_ENFORCE_SYNC, FALSE },
732 { US"no_multiline_responses", CONTROL_NO_MULTILINE, FALSE },
733 { US"no_pipelining", CONTROL_NO_PIPELINING, FALSE },
734 { US"queue_only", CONTROL_QUEUE_ONLY, FALSE },
735 #ifdef WITH_CONTENT_SCAN
736 { US"no_mbox_unspool", CONTROL_NO_MBOX_UNSPOOL, FALSE },
738 { US"fakedefer", CONTROL_FAKEDEFER, TRUE },
739 { US"fakereject", CONTROL_FAKEREJECT, TRUE },
740 { US"submission", CONTROL_SUBMISSION, TRUE },
741 { US"suppress_local_fixups", CONTROL_SUPPRESS_LOCAL_FIXUPS, FALSE },
742 { US"cutthrough_delivery", CONTROL_CUTTHROUGH_DELIVERY, FALSE }
745 /* Support data structures for Client SMTP Authorization. acl_verify_csa()
746 caches its result in a tree to avoid repeated DNS queries. The result is an
747 integer code which is used as an index into the following tables of
748 explanatory strings and verification return codes. */
750 static tree_node *csa_cache = NULL;
752 enum { CSA_UNKNOWN, CSA_OK, CSA_DEFER_SRV, CSA_DEFER_ADDR,
753 CSA_FAIL_EXPLICIT, CSA_FAIL_DOMAIN, CSA_FAIL_NOADDR, CSA_FAIL_MISMATCH };
755 /* The acl_verify_csa() return code is translated into an acl_verify() return
756 code using the following table. It is OK unless the client is definitely not
757 authorized. This is because CSA is supposed to be optional for sending sites,
758 so recipients should not be too strict about checking it - especially because
759 DNS problems are quite likely to occur. It's possible to use $csa_status in
760 further ACL conditions to distinguish ok, unknown, and defer if required, but
761 the aim is to make the usual configuration simple. */
763 static int csa_return_code[] = {
765 FAIL, FAIL, FAIL, FAIL
768 static uschar *csa_status_string[] = {
769 US"unknown", US"ok", US"defer", US"defer",
770 US"fail", US"fail", US"fail", US"fail"
773 static uschar *csa_reason_string[] = {
776 US"deferred (SRV lookup failed)",
777 US"deferred (target address lookup failed)",
778 US"failed (explicit authorization required)",
779 US"failed (host name not authorized)",
780 US"failed (no authorized addresses)",
781 US"failed (client address mismatch)"
784 /* Options for the ratelimit condition. Note that there are two variants of
785 the per_rcpt option, depending on the ACL that is used to measure the rate.
786 However any ACL must be able to look up per_rcpt rates in /noupdate mode,
787 so the two variants must have the same internal representation as well as
788 the same configuration string. */
791 RATE_PER_WHAT, RATE_PER_CLASH, RATE_PER_ADDR, RATE_PER_BYTE, RATE_PER_CMD,
792 RATE_PER_CONN, RATE_PER_MAIL, RATE_PER_RCPT, RATE_PER_ALLRCPTS
795 #define RATE_SET(var,new) \
796 (((var) == RATE_PER_WHAT) ? ((var) = RATE_##new) : ((var) = RATE_PER_CLASH))
798 static uschar *ratelimit_option_string[] = {
799 US"?", US"!", US"per_addr", US"per_byte", US"per_cmd",
800 US"per_conn", US"per_mail", US"per_rcpt", US"per_rcpt"
803 /* Enable recursion between acl_check_internal() and acl_check_condition() */
805 static int acl_check_wargs(int, address_item *, const uschar *, int, uschar **,
809 /*************************************************
810 * Pick out name from list *
811 *************************************************/
813 /* Use a binary chop method
820 Returns: offset in list, or -1 if not found
824 acl_checkname(uschar *name, uschar **list, int end)
830 int mid = (start + end)/2;
831 int c = Ustrcmp(name, list[mid]);
832 if (c == 0) return mid;
833 if (c < 0) end = mid; else start = mid + 1;
840 /*************************************************
841 * Read and parse one ACL *
842 *************************************************/
844 /* This function is called both from readconf in order to parse the ACLs in the
845 configuration file, and also when an ACL is encountered dynamically (e.g. as
846 the result of an expansion). It is given a function to call in order to
847 retrieve the lines of the ACL. This function handles skipping comments and
848 blank lines (where relevant).
851 func function to get next line of ACL
852 error where to put an error message
854 Returns: pointer to ACL, or NULL
855 NULL can be legal (empty ACL); in this case error will be NULL
859 acl_read(uschar *(*func)(void), uschar **error)
861 acl_block *yield = NULL;
862 acl_block **lastp = &yield;
863 acl_block *this = NULL;
864 acl_condition_block *cond;
865 acl_condition_block **condp = NULL;
870 while ((s = (*func)()) != NULL)
873 BOOL negated = FALSE;
874 uschar *saveline = s;
877 /* Conditions (but not verbs) are allowed to be negated by an initial
880 while (isspace(*s)) s++;
887 /* Read the name of a verb or a condition, or the start of a new ACL, which
888 can be started by a name, or by a macro definition. */
890 s = readconf_readname(name, sizeof(name), s);
891 if (*s == ':' || (isupper(name[0]) && *s == '=')) return yield;
893 /* If a verb is unrecognized, it may be another condition or modifier that
894 continues the previous verb. */
896 v = acl_checkname(name, verbs, sizeof(verbs)/sizeof(char *));
901 *error = string_sprintf("unknown ACL verb \"%s\" in \"%s\"", name,
913 *error = string_sprintf("malformed ACL line \"%s\"", saveline);
916 this = store_get(sizeof(acl_block));
918 lastp = &(this->next);
921 this->condition = NULL;
922 condp = &(this->condition);
923 if (*s == 0) continue; /* No condition on this line */
929 s = readconf_readname(name, sizeof(name), s); /* Condition name */
932 /* Handle a condition or modifier. */
934 c = acl_checkname(name, conditions, sizeof(conditions)/sizeof(char *));
937 *error = string_sprintf("unknown ACL condition/modifier in \"%s\"",
942 /* The modifiers may not be negated */
944 if (negated && cond_modifiers[c])
946 *error = string_sprintf("ACL error: negation is not allowed with "
947 "\"%s\"", conditions[c]);
951 /* ENDPASS may occur only with ACCEPT or DISCARD. */
953 if (c == ACLC_ENDPASS &&
954 this->verb != ACL_ACCEPT &&
955 this->verb != ACL_DISCARD)
957 *error = string_sprintf("ACL error: \"%s\" is not allowed with \"%s\"",
958 conditions[c], verbs[this->verb]);
962 cond = store_get(sizeof(acl_condition_block));
965 cond->u.negated = negated;
968 condp = &(cond->next);
970 /* The "set" modifier is different in that its argument is "name=value"
971 rather than just a value, and we can check the validity of the name, which
972 gives us a variable name to insert into the data block. The original ACL
973 variable names were acl_c0 ... acl_c9 and acl_m0 ... acl_m9. This was
974 extended to 20 of each type, but after that people successfully argued for
975 arbitrary names. In the new scheme, the names must start with acl_c or acl_m.
976 After that, we allow alphanumerics and underscores, but the first character
977 after c or m must be a digit or an underscore. This retains backwards
984 if (Ustrncmp(s, "acl_c", 5) != 0 &&
985 Ustrncmp(s, "acl_m", 5) != 0)
987 *error = string_sprintf("invalid variable name after \"set\" in ACL "
988 "modifier \"set %s\" (must start \"acl_c\" or \"acl_m\")", s);
993 if (!isdigit(*endptr) && *endptr != '_')
995 *error = string_sprintf("invalid variable name after \"set\" in ACL "
996 "modifier \"set %s\" (digit or underscore must follow acl_c or acl_m)",
1001 while (*endptr != 0 && *endptr != '=' && !isspace(*endptr))
1003 if (!isalnum(*endptr) && *endptr != '_')
1005 *error = string_sprintf("invalid character \"%c\" in variable name "
1006 "in ACL modifier \"set %s\"", *endptr, s);
1012 cond->u.varname = string_copyn(s + 4, endptr - s - 4);
1014 while (isspace(*s)) s++;
1017 /* For "set", we are now positioned for the data. For the others, only
1018 "endpass" has no data */
1020 if (c != ACLC_ENDPASS)
1024 *error = string_sprintf("\"=\" missing after ACL \"%s\" %s", name,
1025 cond_modifiers[c]? US"modifier" : US"condition");
1028 while (isspace(*s)) s++;
1029 cond->arg = string_copy(s);
1038 /*************************************************
1039 * Set up added header line(s) *
1040 *************************************************/
1042 /* This function is called by the add_header modifier, and also from acl_warn()
1043 to implement the now-deprecated way of adding header lines using "message" on a
1044 "warn" verb. The argument is treated as a sequence of header lines which are
1045 added to a chain, provided there isn't an identical one already there.
1047 Argument: string of header lines
1052 setup_header(const uschar *hstring)
1054 const uschar *p, *q;
1055 int hlen = Ustrlen(hstring);
1057 /* Ignore any leading newlines */
1058 while (*hstring == '\n') hstring++, hlen--;
1060 /* An empty string does nothing; ensure exactly one final newline. */
1061 if (hlen <= 0) return;
1062 if (hstring[--hlen] != '\n')
1063 q = string_sprintf("%s\n", hstring);
1064 else if (hstring[hlen-1] == '\n')
1066 uschar * s = string_copy(hstring);
1067 while(s[--hlen] == '\n')
1074 /* Loop for multiple header lines, taking care about continuations */
1076 for (p = q; *p != 0; )
1080 int newtype = htype_add_bot;
1081 header_line **hptr = &acl_added_headers;
1083 /* Find next header line within the string */
1087 q = Ustrchr(q, '\n');
1088 if (*(++q) != ' ' && *q != '\t') break;
1091 /* If the line starts with a colon, interpret the instruction for where to
1092 add it. This temporarily sets up a new type. */
1096 if (strncmpic(p, US":after_received:", 16) == 0)
1098 newtype = htype_add_rec;
1101 else if (strncmpic(p, US":at_start_rfc:", 14) == 0)
1103 newtype = htype_add_rfc;
1106 else if (strncmpic(p, US":at_start:", 10) == 0)
1108 newtype = htype_add_top;
1111 else if (strncmpic(p, US":at_end:", 8) == 0)
1113 newtype = htype_add_bot;
1116 while (*p == ' ' || *p == '\t') p++;
1119 /* See if this line starts with a header name, and if not, add X-ACL-Warn:
1120 to the front of it. */
1122 for (s = p; s < q - 1; s++)
1124 if (*s == ':' || !isgraph(*s)) break;
1127 hdr = string_sprintf("%s%.*s", (*s == ':')? "" : "X-ACL-Warn: ", (int) (q - p), p);
1128 hlen = Ustrlen(hdr);
1130 /* See if this line has already been added */
1132 while (*hptr != NULL)
1134 if (Ustrncmp((*hptr)->text, hdr, hlen) == 0) break;
1135 hptr = &((*hptr)->next);
1138 /* Add if not previously present */
1142 header_line *h = store_get(sizeof(header_line));
1151 /* Advance for next header line within the string */
1159 /*************************************************
1160 * List the added header lines *
1161 *************************************************/
1165 uschar * ret = NULL;
1166 header_line * h = acl_added_headers;
1172 if (!h) return NULL;
1177 while ((cp = Ustrchr(s, '\n')) != NULL)
1179 if (cp[1] == '\0') break;
1181 /* contains embedded newline; needs doubling */
1182 ret = string_cat(ret, &size, &ptr, s, cp-s+1);
1183 ret = string_cat(ret, &size, &ptr, US"\n", 1);
1186 /* last bit of header */
1188 ret = string_cat(ret, &size, &ptr, s, cp-s+1); /* newline-sep list */
1190 while((h = h->next));
1192 ret[ptr-1] = '\0'; /* overwrite last newline */
1197 /*************************************************
1198 * Set up removed header line(s) *
1199 *************************************************/
1201 /* This function is called by the remove_header modifier. The argument is
1202 treated as a sequence of header names which are added to a colon separated
1203 list, provided there isn't an identical one already there.
1205 Argument: string of header names
1210 setup_remove_header(const uschar *hnames)
1213 acl_removed_headers = acl_removed_headers
1214 ? string_sprintf("%s : %s", acl_removed_headers, hnames)
1215 : string_copy(hnames);
1220 /*************************************************
1222 *************************************************/
1224 /* This function is called when a WARN verb's conditions are true. It adds to
1225 the message's headers, and/or writes information to the log. In each case, this
1226 only happens once (per message for headers, per connection for log).
1228 ** NOTE: The header adding action using the "message" setting is historic, and
1229 its use is now deprecated. The new add_header modifier should be used instead.
1232 where ACL_WHERE_xxxx indicating which ACL this is
1233 user_message message for adding to headers
1234 log_message message for logging, if different
1240 acl_warn(int where, uschar *user_message, uschar *log_message)
1242 if (log_message != NULL && log_message != user_message)
1245 string_item *logged;
1247 text = string_sprintf("%s Warning: %s", host_and_ident(TRUE),
1248 string_printing(log_message));
1250 /* If a sender verification has failed, and the log message is "sender verify
1251 failed", add the failure message. */
1253 if (sender_verified_failed != NULL &&
1254 sender_verified_failed->message != NULL &&
1255 strcmpic(log_message, US"sender verify failed") == 0)
1256 text = string_sprintf("%s: %s", text, sender_verified_failed->message);
1258 /* Search previously logged warnings. They are kept in malloc
1259 store so they can be freed at the start of a new message. */
1261 for (logged = acl_warn_logged; logged != NULL; logged = logged->next)
1262 if (Ustrcmp(logged->text, text) == 0) break;
1266 int length = Ustrlen(text) + 1;
1267 log_write(0, LOG_MAIN, "%s", text);
1268 logged = store_malloc(sizeof(string_item) + length);
1269 logged->text = (uschar *)logged + sizeof(string_item);
1270 memcpy(logged->text, text, length);
1271 logged->next = acl_warn_logged;
1272 acl_warn_logged = logged;
1276 /* If there's no user message, we are done. */
1278 if (user_message == NULL) return;
1280 /* If this isn't a message ACL, we can't do anything with a user message.
1283 if (where > ACL_WHERE_NOTSMTP)
1285 log_write(0, LOG_MAIN|LOG_PANIC, "ACL \"warn\" with \"message\" setting "
1286 "found in a non-message (%s) ACL: cannot specify header lines here: "
1287 "message ignored", acl_wherenames[where]);
1291 /* The code for setting up header lines is now abstracted into a separate
1292 function so that it can be used for the add_header modifier as well. */
1294 setup_header(user_message);
1299 /*************************************************
1300 * Verify and check reverse DNS *
1301 *************************************************/
1303 /* Called from acl_verify() below. We look up the host name(s) of the client IP
1304 address if this has not yet been done. The host_name_lookup() function checks
1305 that one of these names resolves to an address list that contains the client IP
1306 address, so we don't actually have to do the check here.
1309 user_msgptr pointer for user message
1310 log_msgptr pointer for log message
1312 Returns: OK verification condition succeeded
1313 FAIL verification failed
1314 DEFER there was a problem verifying
1318 acl_verify_reverse(uschar **user_msgptr, uschar **log_msgptr)
1322 user_msgptr = user_msgptr; /* stop compiler warning */
1324 /* Previous success */
1326 if (sender_host_name != NULL) return OK;
1328 /* Previous failure */
1330 if (host_lookup_failed)
1332 *log_msgptr = string_sprintf("host lookup failed%s", host_lookup_msg);
1336 /* Need to do a lookup */
1339 debug_printf("looking up host name to force name/address consistency check\n");
1341 if ((rc = host_name_lookup()) != OK)
1343 *log_msgptr = (rc == DEFER)?
1344 US"host lookup deferred for reverse lookup check"
1346 string_sprintf("host lookup failed for reverse lookup check%s",
1348 return rc; /* DEFER or FAIL */
1351 host_build_sender_fullhost();
1357 /*************************************************
1358 * Check client IP address matches CSA target *
1359 *************************************************/
1361 /* Called from acl_verify_csa() below. This routine scans a section of a DNS
1362 response for address records belonging to the CSA target hostname. The section
1363 is specified by the reset argument, either RESET_ADDITIONAL or RESET_ANSWERS.
1364 If one of the addresses matches the client's IP address, then the client is
1365 authorized by CSA. If there are target IP addresses but none of them match
1366 then the client is using an unauthorized IP address. If there are no target IP
1367 addresses then the client cannot be using an authorized IP address. (This is
1368 an odd configuration - why didn't the SRV record have a weight of 1 instead?)
1371 dnsa the DNS answer block
1372 dnss a DNS scan block for us to use
1373 reset option specifing what portion to scan, as described above
1374 target the target hostname to use for matching RR names
1376 Returns: CSA_OK successfully authorized
1377 CSA_FAIL_MISMATCH addresses found but none matched
1378 CSA_FAIL_NOADDR no target addresses found
1382 acl_verify_csa_address(dns_answer *dnsa, dns_scan *dnss, int reset,
1388 BOOL target_found = FALSE;
1390 for (rr = dns_next_rr(dnsa, dnss, reset);
1392 rr = dns_next_rr(dnsa, dnss, RESET_NEXT))
1394 /* Check this is an address RR for the target hostname. */
1398 && 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 #if HAVE_IPV6 && defined(SUPPORT_A6)
1625 lookup_dnssec_authenticated = NULL;
1626 switch (dns_lookup(&dnsa, target, type, NULL))
1628 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1631 return t->data.val = CSA_DEFER_ADDR;
1633 /* If the query succeeded, scan the addresses and return the result. */
1636 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ANSWERS, target);
1637 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1638 /* else fall through */
1640 /* If the target has no IP addresses, the client cannot have an authorized
1641 IP address. However, if the target site uses A6 records (not AAAA records)
1642 we have to do yet another lookup in order to check them. */
1647 #if HAVE_IPV6 && defined(SUPPORT_A6)
1648 if (type == T_AAAA) { type = T_A6; goto DNS_LOOKUP_AGAIN; }
1651 return t->data.val = CSA_FAIL_NOADDR;
1657 /*************************************************
1658 * Handle verification (address & other) *
1659 *************************************************/
1661 enum { VERIFY_REV_HOST_LKUP, VERIFY_CERT, VERIFY_HELO, VERIFY_CSA, VERIFY_HDR_SYNTAX,
1662 VERIFY_NOT_BLIND, VERIFY_HDR_SNDR, VERIFY_SNDR, VERIFY_RCPT,
1663 VERIFY_HDR_NAMES_ASCII
1668 unsigned where_allowed; /* bitmap */
1669 BOOL no_options; /* Never has /option(s) following */
1670 unsigned alt_opt_sep; /* >0 Non-/ option separator (custom parser) */
1672 static verify_type_t verify_type_list[] = {
1673 { US"reverse_host_lookup", VERIFY_REV_HOST_LKUP, ~0, FALSE, 0 },
1674 { US"certificate", VERIFY_CERT, ~0, TRUE, 0 },
1675 { US"helo", VERIFY_HELO, ~0, TRUE, 0 },
1676 { US"csa", VERIFY_CSA, ~0, FALSE, 0 },
1677 { US"header_syntax", VERIFY_HDR_SYNTAX, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), TRUE, 0 },
1678 { US"not_blind", VERIFY_NOT_BLIND, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), TRUE, 0 },
1679 { US"header_sender", VERIFY_HDR_SNDR, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), FALSE, 0 },
1680 { US"sender", VERIFY_SNDR, (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)
1681 |(1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP),
1683 { US"recipient", VERIFY_RCPT, (1<<ACL_WHERE_RCPT), FALSE, 0 },
1684 { US"header_names_ascii", VERIFY_HDR_NAMES_ASCII, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), TRUE, 0 }
1688 enum { CALLOUT_DEFER_OK, CALLOUT_NOCACHE, CALLOUT_RANDOM, CALLOUT_USE_SENDER,
1689 CALLOUT_USE_POSTMASTER, CALLOUT_POSTMASTER, CALLOUT_FULLPOSTMASTER,
1690 CALLOUT_MAILFROM, CALLOUT_POSTMASTER_MAILFROM, CALLOUT_MAXWAIT, CALLOUT_CONNECT,
1697 BOOL has_option; /* Has =option(s) following */
1698 BOOL timeval; /* Has a time value */
1700 static callout_opt_t callout_opt_list[] = {
1701 { US"defer_ok", CALLOUT_DEFER_OK, 0, FALSE, FALSE },
1702 { US"no_cache", CALLOUT_NOCACHE, vopt_callout_no_cache, FALSE, FALSE },
1703 { US"random", CALLOUT_RANDOM, vopt_callout_random, FALSE, FALSE },
1704 { US"use_sender", CALLOUT_USE_SENDER, vopt_callout_recipsender, FALSE, FALSE },
1705 { US"use_postmaster", CALLOUT_USE_POSTMASTER,vopt_callout_recippmaster, FALSE, FALSE },
1706 { US"postmaster_mailfrom",CALLOUT_POSTMASTER_MAILFROM,0, TRUE, FALSE },
1707 { US"postmaster", CALLOUT_POSTMASTER, 0, FALSE, FALSE },
1708 { US"fullpostmaster", CALLOUT_FULLPOSTMASTER,vopt_callout_fullpm, FALSE, FALSE },
1709 { US"mailfrom", CALLOUT_MAILFROM, 0, TRUE, FALSE },
1710 { US"maxwait", CALLOUT_MAXWAIT, 0, TRUE, TRUE },
1711 { US"connect", CALLOUT_CONNECT, 0, TRUE, TRUE },
1712 { NULL, CALLOUT_TIME, 0, FALSE, TRUE }
1717 /* This function implements the "verify" condition. It is called when
1718 encountered in any ACL, because some tests are almost always permitted. Some
1719 just don't make sense, and always fail (for example, an attempt to test a host
1720 lookup for a non-TCP/IP message). Others are restricted to certain ACLs.
1723 where where called from
1724 addr the recipient address that the ACL is handling, or NULL
1725 arg the argument of "verify"
1726 user_msgptr pointer for user message
1727 log_msgptr pointer for log message
1728 basic_errno where to put verify errno
1730 Returns: OK verification condition succeeded
1731 FAIL verification failed
1732 DEFER there was a problem verifying
1737 acl_verify(int where, address_item *addr, const uschar *arg,
1738 uschar **user_msgptr, uschar **log_msgptr, int *basic_errno)
1742 int callout_overall = -1;
1743 int callout_connect = -1;
1744 int verify_options = 0;
1746 BOOL verify_header_sender = FALSE;
1747 BOOL defer_ok = FALSE;
1748 BOOL callout_defer_ok = FALSE;
1749 BOOL no_details = FALSE;
1750 BOOL success_on_redirect = FALSE;
1751 address_item *sender_vaddr = NULL;
1752 uschar *verify_sender_address = NULL;
1753 uschar *pm_mailfrom = NULL;
1754 uschar *se_mailfrom = NULL;
1756 /* Some of the verify items have slash-separated options; some do not. Diagnose
1757 an error if options are given for items that don't expect them.
1760 uschar *slash = Ustrchr(arg, '/');
1761 const uschar *list = arg;
1762 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
1765 if (ss == NULL) goto BAD_VERIFY;
1767 /* Handle name/address consistency verification in a separate function. */
1769 for (vp= verify_type_list;
1770 (char *)vp < (char *)verify_type_list + sizeof(verify_type_list);
1773 if (vp->alt_opt_sep ? strncmpic(ss, vp->name, vp->alt_opt_sep) == 0
1774 : strcmpic (ss, vp->name) == 0)
1776 if ((char *)vp >= (char *)verify_type_list + sizeof(verify_type_list))
1779 if (vp->no_options && slash != NULL)
1781 *log_msgptr = string_sprintf("unexpected '/' found in \"%s\" "
1782 "(this verify item has no options)", arg);
1785 if (!(vp->where_allowed & (1<<where)))
1787 *log_msgptr = string_sprintf("cannot verify %s in ACL for %s", vp->name, acl_wherenames[where]);
1792 case VERIFY_REV_HOST_LKUP:
1793 if (sender_host_address == NULL) return OK;
1794 if ((rc = acl_verify_reverse(user_msgptr, log_msgptr)) == DEFER)
1795 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size)))
1796 if (strcmpic(ss, US"defer_ok") == 0)
1801 /* TLS certificate verification is done at STARTTLS time; here we just
1802 test whether it was successful or not. (This is for optional verification; for
1803 mandatory verification, the connection doesn't last this long.) */
1805 if (tls_in.certificate_verified) return OK;
1806 *user_msgptr = US"no verified certificate";
1810 /* We can test the result of optional HELO verification that might have
1811 occurred earlier. If not, we can attempt the verification now. */
1813 if (!helo_verified && !helo_verify_failed) smtp_verify_helo();
1814 return helo_verified? OK : FAIL;
1817 /* Do Client SMTP Authorization checks in a separate function, and turn the
1818 result code into user-friendly strings. */
1820 rc = acl_verify_csa(list);
1821 *log_msgptr = *user_msgptr = string_sprintf("client SMTP authorization %s",
1822 csa_reason_string[rc]);
1823 csa_status = csa_status_string[rc];
1824 DEBUG(D_acl) debug_printf("CSA result %s\n", csa_status);
1825 return csa_return_code[rc];
1827 case VERIFY_HDR_SYNTAX:
1828 /* Check that all relevant header lines have the correct syntax. If there is
1829 a syntax error, we return details of the error to the sender if configured to
1830 send out full details. (But a "message" setting on the ACL can override, as
1833 rc = verify_check_headers(log_msgptr);
1834 if (rc != OK && smtp_return_error_details && *log_msgptr != NULL)
1835 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1838 case VERIFY_HDR_NAMES_ASCII:
1839 /* Check that all header names are true 7 bit strings
1840 See RFC 5322, 2.2. and RFC 6532, 3. */
1842 rc = verify_check_header_names_ascii(log_msgptr);
1843 if (rc != OK && smtp_return_error_details && *log_msgptr != NULL)
1844 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1847 case VERIFY_NOT_BLIND:
1848 /* Check that no recipient of this message is "blind", that is, every envelope
1849 recipient must be mentioned in either To: or Cc:. */
1851 rc = verify_check_notblind();
1854 *log_msgptr = string_sprintf("bcc recipient detected");
1855 if (smtp_return_error_details)
1856 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1860 /* The remaining verification tests check recipient and sender addresses,
1861 either from the envelope or from the header. There are a number of
1862 slash-separated options that are common to all of them. */
1864 case VERIFY_HDR_SNDR:
1865 verify_header_sender = TRUE;
1869 /* In the case of a sender, this can optionally be followed by an address to use
1870 in place of the actual sender (rare special-case requirement). */
1874 verify_sender_address = sender_address;
1877 while (isspace(*s)) s++;
1878 if (*s++ != '=') goto BAD_VERIFY;
1879 while (isspace(*s)) s++;
1880 verify_sender_address = string_copy(s);
1891 /* Remaining items are optional; they apply to sender and recipient
1892 verification, including "header sender" verification. */
1894 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size))
1897 if (strcmpic(ss, US"defer_ok") == 0) defer_ok = TRUE;
1898 else if (strcmpic(ss, US"no_details") == 0) no_details = TRUE;
1899 else if (strcmpic(ss, US"success_on_redirect") == 0) success_on_redirect = TRUE;
1901 /* These two old options are left for backwards compatibility */
1903 else if (strcmpic(ss, US"callout_defer_ok") == 0)
1905 callout_defer_ok = TRUE;
1906 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1909 else if (strcmpic(ss, US"check_postmaster") == 0)
1912 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1915 /* The callout option has a number of sub-options, comma separated */
1917 else if (strncmpic(ss, US"callout", 7) == 0)
1919 callout = CALLOUT_TIMEOUT_DEFAULT;
1923 while (isspace(*ss)) ss++;
1926 const uschar * sublist = ss;
1930 while (isspace(*sublist)) sublist++;
1932 while ((opt = string_nextinlist(&sublist, &optsep, buffer, sizeof(buffer)))
1936 double period = 1.0F;
1938 for (op= callout_opt_list; op->name; op++)
1939 if (strncmpic(opt, op->name, Ustrlen(op->name)) == 0)
1942 verify_options |= op->flag;
1945 opt += Ustrlen(op->name);
1946 while (isspace(*opt)) opt++;
1949 *log_msgptr = string_sprintf("'=' expected after "
1950 "\"%s\" in ACL verify condition \"%s\"", op->name, arg);
1953 while (isspace(*opt)) opt++;
1957 period = readconf_readtime(opt, 0, FALSE);
1960 *log_msgptr = string_sprintf("bad time value in ACL condition "
1961 "\"verify %s\"", arg);
1968 case CALLOUT_DEFER_OK: callout_defer_ok = TRUE; break;
1969 case CALLOUT_POSTMASTER: pm_mailfrom = US""; break;
1970 case CALLOUT_FULLPOSTMASTER: pm_mailfrom = US""; break;
1971 case CALLOUT_MAILFROM:
1972 if (!verify_header_sender)
1974 *log_msgptr = string_sprintf("\"mailfrom\" is allowed as a "
1975 "callout option only for verify=header_sender (detected in ACL "
1976 "condition \"%s\")", arg);
1979 se_mailfrom = string_copy(opt);
1981 case CALLOUT_POSTMASTER_MAILFROM: pm_mailfrom = string_copy(opt); break;
1982 case CALLOUT_MAXWAIT: callout_overall = period; break;
1983 case CALLOUT_CONNECT: callout_connect = period; break;
1984 case CALLOUT_TIME: callout = period; break;
1990 *log_msgptr = string_sprintf("'=' expected after \"callout\" in "
1991 "ACL condition \"%s\"", arg);
1997 /* Option not recognized */
2001 *log_msgptr = string_sprintf("unknown option \"%s\" in ACL "
2002 "condition \"verify %s\"", ss, arg);
2007 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster)) ==
2008 (vopt_callout_recipsender|vopt_callout_recippmaster))
2010 *log_msgptr = US"only one of use_sender and use_postmaster can be set "
2011 "for a recipient callout";
2015 /* Handle sender-in-header verification. Default the user message to the log
2016 message if giving out verification details. */
2018 if (verify_header_sender)
2021 rc = verify_check_header_address(user_msgptr, log_msgptr, callout,
2022 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, verify_options,
2026 *basic_errno = verrno;
2027 if (smtp_return_error_details)
2029 if (*user_msgptr == NULL && *log_msgptr != NULL)
2030 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
2031 if (rc == DEFER) acl_temp_details = TRUE;
2036 /* Handle a sender address. The default is to verify *the* sender address, but
2037 optionally a different address can be given, for special requirements. If the
2038 address is empty, we are dealing with a bounce message that has no sender, so
2039 we cannot do any checking. If the real sender address gets rewritten during
2040 verification (e.g. DNS widening), set the flag to stop it being rewritten again
2041 during message reception.
2043 A list of verified "sender" addresses is kept to try to avoid doing to much
2044 work repetitively when there are multiple recipients in a message and they all
2045 require sender verification. However, when callouts are involved, it gets too
2046 complicated because different recipients may require different callout options.
2047 Therefore, we always do a full sender verify when any kind of callout is
2048 specified. Caching elsewhere, for instance in the DNS resolver and in the
2049 callout handling, should ensure that this is not terribly inefficient. */
2051 else if (verify_sender_address != NULL)
2053 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster))
2056 *log_msgptr = US"use_sender or use_postmaster cannot be used for a "
2057 "sender verify callout";
2061 sender_vaddr = verify_checked_sender(verify_sender_address);
2062 if (sender_vaddr != NULL && /* Previously checked */
2063 callout <= 0) /* No callout needed this time */
2065 /* If the "routed" flag is set, it means that routing worked before, so
2066 this check can give OK (the saved return code value, if set, belongs to a
2067 callout that was done previously). If the "routed" flag is not set, routing
2068 must have failed, so we use the saved return code. */
2070 if (testflag(sender_vaddr, af_verify_routed)) rc = OK; else
2072 rc = sender_vaddr->special_action;
2073 *basic_errno = sender_vaddr->basic_errno;
2075 HDEBUG(D_acl) debug_printf("using cached sender verify result\n");
2078 /* Do a new verification, and cache the result. The cache is used to avoid
2079 verifying the sender multiple times for multiple RCPTs when callouts are not
2080 specified (see comments above).
2082 The cache is also used on failure to give details in response to the first
2083 RCPT that gets bounced for this reason. However, this can be suppressed by
2084 the no_details option, which sets the flag that says "this detail has already
2085 been sent". The cache normally contains just one address, but there may be
2086 more in esoteric circumstances. */
2091 uschar *save_address_data = deliver_address_data;
2093 sender_vaddr = deliver_make_addr(verify_sender_address, TRUE);
2094 if (no_details) setflag(sender_vaddr, af_sverify_told);
2095 if (verify_sender_address[0] != 0)
2097 /* If this is the real sender address, save the unrewritten version
2098 for use later in receive. Otherwise, set a flag so that rewriting the
2099 sender in verify_address() does not update sender_address. */
2101 if (verify_sender_address == sender_address)
2102 sender_address_unrewritten = sender_address;
2104 verify_options |= vopt_fake_sender;
2106 if (success_on_redirect)
2107 verify_options |= vopt_success_on_redirect;
2109 /* The recipient, qualify, and expn options are never set in
2112 rc = verify_address(sender_vaddr, NULL, verify_options, callout,
2113 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, &routed);
2115 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
2119 if (Ustrcmp(sender_vaddr->address, verify_sender_address) != 0)
2121 DEBUG(D_acl) debug_printf("sender %s verified ok as %s\n",
2122 verify_sender_address, sender_vaddr->address);
2126 DEBUG(D_acl) debug_printf("sender %s verified ok\n",
2127 verify_sender_address);
2130 else *basic_errno = sender_vaddr->basic_errno;
2132 else rc = OK; /* Null sender */
2134 /* Cache the result code */
2136 if (routed) setflag(sender_vaddr, af_verify_routed);
2137 if (callout > 0) setflag(sender_vaddr, af_verify_callout);
2138 sender_vaddr->special_action = rc;
2139 sender_vaddr->next = sender_verified_list;
2140 sender_verified_list = sender_vaddr;
2142 /* Restore the recipient address data, which might have been clobbered by
2143 the sender verification. */
2145 deliver_address_data = save_address_data;
2148 /* Put the sender address_data value into $sender_address_data */
2150 sender_address_data = sender_vaddr->p.address_data;
2153 /* A recipient address just gets a straightforward verify; again we must handle
2154 the DEFER overrides. */
2160 if (success_on_redirect)
2161 verify_options |= vopt_success_on_redirect;
2163 /* We must use a copy of the address for verification, because it might
2167 rc = verify_address(&addr2, NULL, verify_options|vopt_is_recipient, callout,
2168 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, NULL);
2169 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
2171 *basic_errno = addr2.basic_errno;
2172 *log_msgptr = addr2.message;
2173 *user_msgptr = (addr2.user_message != NULL)?
2174 addr2.user_message : addr2.message;
2176 /* Allow details for temporary error if the address is so flagged. */
2177 if (testflag((&addr2), af_pass_message)) acl_temp_details = TRUE;
2179 /* Make $address_data visible */
2180 deliver_address_data = addr2.p.address_data;
2183 /* We have a result from the relevant test. Handle defer overrides first. */
2185 if (rc == DEFER && (defer_ok ||
2186 (callout_defer_ok && *basic_errno == ERRNO_CALLOUTDEFER)))
2188 HDEBUG(D_acl) debug_printf("verify defer overridden by %s\n",
2189 defer_ok? "defer_ok" : "callout_defer_ok");
2193 /* If we've failed a sender, set up a recipient message, and point
2194 sender_verified_failed to the address item that actually failed. */
2196 if (rc != OK && verify_sender_address != NULL)
2200 *log_msgptr = *user_msgptr = US"Sender verify failed";
2202 else if (*basic_errno != ERRNO_CALLOUTDEFER)
2204 *log_msgptr = *user_msgptr = US"Could not complete sender verify";
2208 *log_msgptr = US"Could not complete sender verify callout";
2209 *user_msgptr = smtp_return_error_details? sender_vaddr->user_message :
2213 sender_verified_failed = sender_vaddr;
2216 /* Verifying an address messes up the values of $domain and $local_part,
2217 so reset them before returning if this is a RCPT ACL. */
2221 deliver_domain = addr->domain;
2222 deliver_localpart = addr->local_part;
2226 /* Syntax errors in the verify argument come here. */
2229 *log_msgptr = string_sprintf("expected \"sender[=address]\", \"recipient\", "
2230 "\"helo\", \"header_syntax\", \"header_sender\", \"header_names_ascii\" "
2231 "or \"reverse_host_lookup\" at start of ACL condition "
2232 "\"verify %s\"", arg);
2239 /*************************************************
2240 * Check argument for control= modifier *
2241 *************************************************/
2243 /* Called from acl_check_condition() below
2246 arg the argument string for control=
2247 pptr set to point to the terminating character
2248 where which ACL we are in
2249 log_msgptr for error messages
2251 Returns: CONTROL_xxx value
2255 decode_control(const uschar *arg, const uschar **pptr, int where, uschar **log_msgptr)
2260 for (d = controls_list;
2261 d < controls_list + sizeof(controls_list)/sizeof(control_def);
2264 len = Ustrlen(d->name);
2265 if (Ustrncmp(d->name, arg, len) == 0) break;
2268 if (d >= controls_list + sizeof(controls_list)/sizeof(control_def) ||
2269 (arg[len] != 0 && (!d->has_option || arg[len] != '/')))
2271 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
2272 return CONTROL_ERROR;
2282 /*************************************************
2283 * Return a ratelimit error *
2284 *************************************************/
2286 /* Called from acl_ratelimit() below
2289 log_msgptr for error messages
2290 format format string
2291 ... supplementary arguments
2292 ss ratelimit option name
2293 where ACL_WHERE_xxxx indicating which ACL this is
2299 ratelimit_error(uschar **log_msgptr, const char *format, ...)
2302 uschar buffer[STRING_SPRINTF_BUFFER_SIZE];
2303 va_start(ap, format);
2304 if (!string_vformat(buffer, sizeof(buffer), format, ap))
2305 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
2306 "string_sprintf expansion was longer than " SIZE_T_FMT, sizeof(buffer));
2308 *log_msgptr = string_sprintf(
2309 "error in arguments to \"ratelimit\" condition: %s", buffer);
2316 /*************************************************
2317 * Handle rate limiting *
2318 *************************************************/
2320 /* Called by acl_check_condition() below to calculate the result
2321 of the ACL ratelimit condition.
2323 Note that the return value might be slightly unexpected: if the
2324 sender's rate is above the limit then the result is OK. This is
2325 similar to the dnslists condition, and is so that you can write
2326 ACL clauses like: defer ratelimit = 15 / 1h
2329 arg the option string for ratelimit=
2330 where ACL_WHERE_xxxx indicating which ACL this is
2331 log_msgptr for error messages
2333 Returns: OK - Sender's rate is above limit
2334 FAIL - Sender's rate is below limit
2335 DEFER - Problem opening ratelimit database
2336 ERROR - Syntax error in options.
2340 acl_ratelimit(const uschar *arg, int where, uschar **log_msgptr)
2342 double limit, period, count;
2345 uschar *unique = NULL;
2347 BOOL leaky = FALSE, strict = FALSE, readonly = FALSE;
2348 BOOL noupdate = FALSE, badacl = FALSE;
2349 int mode = RATE_PER_WHAT;
2351 tree_node **anchor, *t;
2352 open_db dbblock, *dbm;
2354 dbdata_ratelimit *dbd;
2355 dbdata_ratelimit_unique *dbdb;
2358 /* Parse the first two options and record their values in expansion
2359 variables. These variables allow the configuration to have informative
2360 error messages based on rate limits obtained from a table lookup. */
2362 /* First is the maximum number of messages per period / maximum burst
2363 size, which must be greater than or equal to zero. Zero is useful for
2364 rate measurement as opposed to rate limiting. */
2366 sender_rate_limit = string_nextinlist(&arg, &sep, NULL, 0);
2367 if (sender_rate_limit == NULL)
2370 ss = NULL; /* compiler quietening */
2374 limit = Ustrtod(sender_rate_limit, &ss);
2375 if (tolower(*ss) == 'k') { limit *= 1024.0; ss++; }
2376 else if (tolower(*ss) == 'm') { limit *= 1024.0*1024.0; ss++; }
2377 else if (tolower(*ss) == 'g') { limit *= 1024.0*1024.0*1024.0; ss++; }
2379 if (limit < 0.0 || *ss != '\0')
2380 return ratelimit_error(log_msgptr,
2381 "\"%s\" is not a positive number", sender_rate_limit);
2383 /* Second is the rate measurement period / exponential smoothing time
2384 constant. This must be strictly greater than zero, because zero leads to
2385 run-time division errors. */
2387 sender_rate_period = string_nextinlist(&arg, &sep, NULL, 0);
2388 if (sender_rate_period == NULL) period = -1.0;
2389 else period = readconf_readtime(sender_rate_period, 0, FALSE);
2391 return ratelimit_error(log_msgptr,
2392 "\"%s\" is not a time value", sender_rate_period);
2394 /* By default we are counting one of something, but the per_rcpt,
2395 per_byte, and count options can change this. */
2399 /* Parse the other options. */
2401 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2404 if (strcmpic(ss, US"leaky") == 0) leaky = TRUE;
2405 else if (strcmpic(ss, US"strict") == 0) strict = TRUE;
2406 else if (strcmpic(ss, US"noupdate") == 0) noupdate = TRUE;
2407 else if (strcmpic(ss, US"readonly") == 0) readonly = TRUE;
2408 else if (strcmpic(ss, US"per_cmd") == 0) RATE_SET(mode, PER_CMD);
2409 else if (strcmpic(ss, US"per_conn") == 0)
2411 RATE_SET(mode, PER_CONN);
2412 if (where == ACL_WHERE_NOTSMTP || where == ACL_WHERE_NOTSMTP_START)
2415 else if (strcmpic(ss, US"per_mail") == 0)
2417 RATE_SET(mode, PER_MAIL);
2418 if (where > ACL_WHERE_NOTSMTP) badacl = TRUE;
2420 else if (strcmpic(ss, US"per_rcpt") == 0)
2422 /* If we are running in the RCPT ACL, then we'll count the recipients
2423 one by one, but if we are running when we have accumulated the whole
2424 list then we'll add them all in one batch. */
2425 if (where == ACL_WHERE_RCPT)
2426 RATE_SET(mode, PER_RCPT);
2427 else if (where >= ACL_WHERE_PREDATA && where <= ACL_WHERE_NOTSMTP)
2428 RATE_SET(mode, PER_ALLRCPTS), count = (double)recipients_count;
2429 else if (where == ACL_WHERE_MAIL || where > ACL_WHERE_NOTSMTP)
2430 RATE_SET(mode, PER_RCPT), badacl = TRUE;
2432 else if (strcmpic(ss, US"per_byte") == 0)
2434 /* If we have not yet received the message data and there was no SIZE
2435 declaration on the MAIL comand, then it's safe to just use a value of
2436 zero and let the recorded rate decay as if nothing happened. */
2437 RATE_SET(mode, PER_MAIL);
2438 if (where > ACL_WHERE_NOTSMTP) badacl = TRUE;
2439 else count = message_size < 0 ? 0.0 : (double)message_size;
2441 else if (strcmpic(ss, US"per_addr") == 0)
2443 RATE_SET(mode, PER_RCPT);
2444 if (where != ACL_WHERE_RCPT) badacl = TRUE, unique = US"*";
2445 else unique = string_sprintf("%s@%s", deliver_localpart, deliver_domain);
2447 else if (strncmpic(ss, US"count=", 6) == 0)
2450 count = Ustrtod(ss+6, &e);
2451 if (count < 0.0 || *e != '\0')
2452 return ratelimit_error(log_msgptr,
2453 "\"%s\" is not a positive number", ss);
2455 else if (strncmpic(ss, US"unique=", 7) == 0)
2456 unique = string_copy(ss + 7);
2457 else if (key == NULL)
2458 key = string_copy(ss);
2460 key = string_sprintf("%s/%s", key, ss);
2463 /* Sanity check. When the badacl flag is set the update mode must either
2464 be readonly (which is the default if it is omitted) or, for backwards
2465 compatibility, a combination of noupdate and strict or leaky. */
2467 if (mode == RATE_PER_CLASH)
2468 return ratelimit_error(log_msgptr, "conflicting per_* options");
2469 if (leaky + strict + readonly > 1)
2470 return ratelimit_error(log_msgptr, "conflicting update modes");
2471 if (badacl && (leaky || strict) && !noupdate)
2472 return ratelimit_error(log_msgptr,
2473 "\"%s\" must not have /leaky or /strict option in %s ACL",
2474 ratelimit_option_string[mode], acl_wherenames[where]);
2476 /* Set the default values of any unset options. In readonly mode we
2477 perform the rate computation without any increment so that its value
2478 decays to eventually allow over-limit senders through. */
2480 if (noupdate) readonly = TRUE, leaky = strict = FALSE;
2481 if (badacl) readonly = TRUE;
2482 if (readonly) count = 0.0;
2483 if (!strict && !readonly) leaky = TRUE;
2484 if (mode == RATE_PER_WHAT) mode = RATE_PER_MAIL;
2486 /* Create the lookup key. If there is no explicit key, use sender_host_address.
2487 If there is no sender_host_address (e.g. -bs or acl_not_smtp) then we simply
2488 omit it. The smoothing constant (sender_rate_period) and the per_xxx options
2489 are added to the key because they alter the meaning of the stored data. */
2492 key = (sender_host_address == NULL)? US"" : sender_host_address;
2494 key = string_sprintf("%s/%s/%s%s",
2496 ratelimit_option_string[mode],
2497 unique == NULL ? "" : "unique/",
2501 debug_printf("ratelimit condition count=%.0f %.1f/%s\n", count, limit, key);
2503 /* See if we have already computed the rate by looking in the relevant tree.
2504 For per-connection rate limiting, store tree nodes and dbdata in the permanent
2505 pool so that they survive across resets. In readonly mode we only remember the
2506 result for the rest of this command in case a later command changes it. After
2507 this bit of logic the code is independent of the per_* mode. */
2509 old_pool = store_pool;
2512 anchor = &ratelimiters_cmd;
2515 anchor = &ratelimiters_conn;
2516 store_pool = POOL_PERM;
2520 case RATE_PER_ALLRCPTS:
2521 anchor = &ratelimiters_mail;
2526 anchor = &ratelimiters_cmd;
2529 anchor = NULL; /* silence an "unused" complaint */
2530 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
2531 "internal ACL error: unknown ratelimit mode %d", mode);
2535 t = tree_search(*anchor, key);
2539 /* The following few lines duplicate some of the code below. */
2540 rc = (dbd->rate < limit)? FAIL : OK;
2541 store_pool = old_pool;
2542 sender_rate = string_sprintf("%.1f", dbd->rate);
2544 debug_printf("ratelimit found pre-computed rate %s\n", sender_rate);
2548 /* We aren't using a pre-computed rate, so get a previously recorded rate
2549 from the database, which will be updated and written back if required. */
2551 dbm = dbfn_open(US"ratelimit", O_RDWR, &dbblock, TRUE);
2554 store_pool = old_pool;
2556 HDEBUG(D_acl) debug_printf("ratelimit database not available\n");
2557 *log_msgptr = US"ratelimit database not available";
2560 dbdb = dbfn_read_with_length(dbm, key, &dbdb_size);
2563 gettimeofday(&tv, NULL);
2567 /* Locate the basic ratelimit block inside the DB data. */
2568 HDEBUG(D_acl) debug_printf("ratelimit found key in database\n");
2571 /* Forget the old Bloom filter if it is too old, so that we count each
2572 repeating event once per period. We don't simply clear and re-use the old
2573 filter because we want its size to change if the limit changes. Note that
2574 we keep the dbd pointer for copying the rate into the new data block. */
2576 if(unique != NULL && tv.tv_sec > dbdb->bloom_epoch + period)
2578 HDEBUG(D_acl) debug_printf("ratelimit discarding old Bloom filter\n");
2584 if(unique != NULL && dbdb_size < sizeof(*dbdb))
2586 HDEBUG(D_acl) debug_printf("ratelimit discarding undersize Bloom filter\n");
2591 /* Allocate a new data block if the database lookup failed
2592 or the Bloom filter passed its age limit. */
2598 /* No Bloom filter. This basic ratelimit block is initialized below. */
2599 HDEBUG(D_acl) debug_printf("ratelimit creating new rate data block\n");
2600 dbdb_size = sizeof(*dbd);
2601 dbdb = store_get(dbdb_size);
2606 HDEBUG(D_acl) debug_printf("ratelimit creating new Bloom filter\n");
2608 /* See the long comment below for an explanation of the magic number 2.
2609 The filter has a minimum size in case the rate limit is very small;
2610 this is determined by the definition of dbdata_ratelimit_unique. */
2612 extra = (int)limit * 2 - sizeof(dbdb->bloom);
2613 if (extra < 0) extra = 0;
2614 dbdb_size = sizeof(*dbdb) + extra;
2615 dbdb = store_get(dbdb_size);
2616 dbdb->bloom_epoch = tv.tv_sec;
2617 dbdb->bloom_size = sizeof(dbdb->bloom) + extra;
2618 memset(dbdb->bloom, 0, dbdb->bloom_size);
2620 /* Preserve any basic ratelimit data (which is our longer-term memory)
2621 by copying it from the discarded block. */
2631 /* If we are counting unique events, find out if this event is new or not.
2632 If the client repeats the event during the current period then it should be
2633 counted. We skip this code in readonly mode for efficiency, because any
2634 changes to the filter will be discarded and because count is already set to
2637 if (unique != NULL && !readonly)
2639 /* We identify unique events using a Bloom filter. (You can find my
2640 notes on Bloom filters at http://fanf.livejournal.com/81696.html)
2641 With the per_addr option, an "event" is a recipient address, though the
2642 user can use the unique option to define their own events. We only count
2643 an event if we have not seen it before.
2645 We size the filter according to the rate limit, which (in leaky mode)
2646 is the limit on the population of the filter. We allow 16 bits of space
2647 per entry (see the construction code above) and we set (up to) 8 of them
2648 when inserting an element (see the loop below). The probability of a false
2649 positive (an event we have not seen before but which we fail to count) is
2653 allzero = exp(-numhash * pop / size)
2654 = exp(-0.5 * pop / limit)
2655 fpr = pow(1 - allzero, numhash)
2657 For senders at the limit the fpr is 0.06% or 1 in 1700
2658 and for senders at half the limit it is 0.0006% or 1 in 170000
2660 In strict mode the Bloom filter can fill up beyond the normal limit, in
2661 which case the false positive rate will rise. This means that the
2662 measured rate for very fast senders can bogusly drop off after a while.
2664 At twice the limit, the fpr is 2.5% or 1 in 40
2665 At four times the limit, it is 31% or 1 in 3.2
2667 It takes ln(pop/limit) periods for an over-limit burst of pop events to
2668 decay below the limit, and if this is more than one then the Bloom filter
2669 will be discarded before the decay gets that far. The false positive rate
2670 at this threshold is 9.3% or 1 in 10.7. */
2673 unsigned n, hash, hinc;
2677 /* Instead of using eight independent hash values, we combine two values
2678 using the formula h1 + n * h2. This does not harm the Bloom filter's
2679 performance, and means the amount of hash we need is independent of the
2680 number of bits we set in the filter. */
2682 md5_start(&md5info);
2683 md5_end(&md5info, unique, Ustrlen(unique), md5sum);
2684 hash = md5sum[0] | md5sum[1] << 8 | md5sum[2] << 16 | md5sum[3] << 24;
2685 hinc = md5sum[4] | md5sum[5] << 8 | md5sum[6] << 16 | md5sum[7] << 24;
2687 /* Scan the bits corresponding to this event. A zero bit means we have
2688 not seen it before. Ensure all bits are set to record this event. */
2690 HDEBUG(D_acl) debug_printf("ratelimit checking uniqueness of %s\n", unique);
2693 for (n = 0; n < 8; n++, hash += hinc)
2695 int bit = 1 << (hash % 8);
2696 int byte = (hash / 8) % dbdb->bloom_size;
2697 if ((dbdb->bloom[byte] & bit) == 0)
2699 dbdb->bloom[byte] |= bit;
2704 /* If this event has occurred before, do not count it. */
2708 HDEBUG(D_acl) debug_printf("ratelimit event found in Bloom filter\n");
2712 HDEBUG(D_acl) debug_printf("ratelimit event added to Bloom filter\n");
2715 /* If there was no previous ratelimit data block for this key, initialize
2716 the new one, otherwise update the block from the database. The initial rate
2717 is what would be computed by the code below for an infinite interval. */
2721 HDEBUG(D_acl) debug_printf("ratelimit initializing new key's rate data\n");
2723 dbd->time_stamp = tv.tv_sec;
2724 dbd->time_usec = tv.tv_usec;
2729 /* The smoothed rate is computed using an exponentially weighted moving
2730 average adjusted for variable sampling intervals. The standard EWMA for
2731 a fixed sampling interval is: f'(t) = (1 - a) * f(t) + a * f'(t - 1)
2732 where f() is the measured value and f'() is the smoothed value.
2734 Old data decays out of the smoothed value exponentially, such that data n
2735 samples old is multiplied by a^n. The exponential decay time constant p
2736 is defined such that data p samples old is multiplied by 1/e, which means
2737 that a = exp(-1/p). We can maintain the same time constant for a variable
2738 sampling interval i by using a = exp(-i/p).
2740 The rate we are measuring is messages per period, suitable for directly
2741 comparing with the limit. The average rate between now and the previous
2742 message is period / interval, which we feed into the EWMA as the sample.
2744 It turns out that the number of messages required for the smoothed rate
2745 to reach the limit when they are sent in a burst is equal to the limit.
2746 This can be seen by analysing the value of the smoothed rate after N
2747 messages sent at even intervals. Let k = (1 - a) * p/i
2749 rate_1 = (1 - a) * p/i + a * rate_0
2751 rate_2 = k + a * rate_1
2752 = k + a * k + a^2 * rate_0
2753 rate_3 = k + a * k + a^2 * k + a^3 * rate_0
2754 rate_N = rate_0 * a^N + k * SUM(x=0..N-1)(a^x)
2755 = rate_0 * a^N + k * (1 - a^N) / (1 - a)
2756 = rate_0 * a^N + p/i * (1 - a^N)
2758 When N is large, a^N -> 0 so rate_N -> p/i as desired.
2760 rate_N = p/i + (rate_0 - p/i) * a^N
2761 a^N = (rate_N - p/i) / (rate_0 - p/i)
2762 N * -i/p = log((rate_N - p/i) / (rate_0 - p/i))
2763 N = p/i * log((rate_0 - p/i) / (rate_N - p/i))
2765 Numerical analysis of the above equation, setting the computed rate to
2766 increase from rate_0 = 0 to rate_N = limit, shows that for large sending
2767 rates, p/i, the number of messages N = limit. So limit serves as both the
2768 maximum rate measured in messages per period, and the maximum number of
2769 messages that can be sent in a fast burst. */
2771 double this_time = (double)tv.tv_sec
2772 + (double)tv.tv_usec / 1000000.0;
2773 double prev_time = (double)dbd->time_stamp
2774 + (double)dbd->time_usec / 1000000.0;
2776 /* We must avoid division by zero, and deal gracefully with the clock going
2777 backwards. If we blunder ahead when time is in reverse then the computed
2778 rate will be bogus. To be safe we clamp interval to a very small number. */
2780 double interval = this_time - prev_time <= 0.0 ? 1e-9
2781 : this_time - prev_time;
2783 double i_over_p = interval / period;
2784 double a = exp(-i_over_p);
2786 /* Combine the instantaneous rate (period / interval) with the previous rate
2787 using the smoothing factor a. In order to measure sized events, multiply the
2788 instantaneous rate by the count of bytes or recipients etc. */
2790 dbd->time_stamp = tv.tv_sec;
2791 dbd->time_usec = tv.tv_usec;
2792 dbd->rate = (1 - a) * count / i_over_p + a * dbd->rate;
2794 /* When events are very widely spaced the computed rate tends towards zero.
2795 Although this is accurate it turns out not to be useful for our purposes,
2796 especially when the first event after a long silence is the start of a spam
2797 run. A more useful model is that the rate for an isolated event should be the
2798 size of the event per the period size, ignoring the lack of events outside
2799 the current period and regardless of where the event falls in the period. So,
2800 if the interval was so long that the calculated rate is unhelpfully small, we
2801 re-intialize the rate. In the absence of higher-rate bursts, the condition
2802 below is true if the interval is greater than the period. */
2804 if (dbd->rate < count) dbd->rate = count;
2807 /* Clients sending at the limit are considered to be over the limit.
2808 This matters for edge cases such as a limit of zero, when the client
2809 should be completely blocked. */
2811 rc = (dbd->rate < limit)? FAIL : OK;
2813 /* Update the state if the rate is low or if we are being strict. If we
2814 are in leaky mode and the sender's rate is too high, we do not update
2815 the recorded rate in order to avoid an over-aggressive sender's retry
2816 rate preventing them from getting any email through. If readonly is set,
2817 neither leaky nor strict are set, so we do not do any updates. */
2819 if ((rc == FAIL && leaky) || strict)
2821 dbfn_write(dbm, key, dbdb, dbdb_size);
2822 HDEBUG(D_acl) debug_printf("ratelimit db updated\n");
2826 HDEBUG(D_acl) debug_printf("ratelimit db not updated: %s\n",
2827 readonly? "readonly mode" : "over the limit, but leaky");
2832 /* Store the result in the tree for future reference. */
2834 t = store_get(sizeof(tree_node) + Ustrlen(key));
2836 Ustrcpy(t->name, key);
2837 (void)tree_insertnode(anchor, t);
2839 /* We create the formatted version of the sender's rate very late in
2840 order to ensure that it is done using the correct storage pool. */
2842 store_pool = old_pool;
2843 sender_rate = string_sprintf("%.1f", dbd->rate);
2846 debug_printf("ratelimit computed rate %s\n", sender_rate);
2853 /*************************************************
2854 * The udpsend ACL modifier *
2855 *************************************************/
2857 /* Called by acl_check_condition() below.
2860 arg the option string for udpsend=
2861 log_msgptr for error messages
2863 Returns: OK - Completed.
2864 DEFER - Problem with DNS lookup.
2865 ERROR - Syntax error in options.
2869 acl_udpsend(const uschar *arg, uschar **log_msgptr)
2881 hostname = string_nextinlist(&arg, &sep, NULL, 0);
2882 portstr = string_nextinlist(&arg, &sep, NULL, 0);
2884 if (hostname == NULL)
2886 *log_msgptr = US"missing destination host in \"udpsend\" modifier";
2889 if (portstr == NULL)
2891 *log_msgptr = US"missing destination port in \"udpsend\" modifier";
2896 *log_msgptr = US"missing datagram payload in \"udpsend\" modifier";
2899 portnum = Ustrtol(portstr, &portend, 10);
2900 if (*portend != '\0')
2902 *log_msgptr = US"bad destination port in \"udpsend\" modifier";
2906 /* Make a single-item host list. */
2907 h = store_get(sizeof(host_item));
2908 memset(h, 0, sizeof(host_item));
2913 if (string_is_ip_address(hostname, NULL))
2914 h->address = hostname, r = HOST_FOUND;
2916 r = host_find_byname(h, NULL, 0, NULL, FALSE);
2917 if (r == HOST_FIND_FAILED || r == HOST_FIND_AGAIN)
2919 *log_msgptr = US"DNS lookup failed in \"udpsend\" modifier";
2924 debug_printf("udpsend [%s]:%d %s\n", h->address, portnum, arg);
2926 r = s = ip_connectedsocket(SOCK_DGRAM, h->address, portnum, portnum,
2928 if (r < 0) goto defer;
2930 r = send(s, arg, len, 0);
2933 errstr = US strerror(errno);
2941 string_sprintf("\"udpsend\" truncated from %d to %d octets", len, r);
2946 debug_printf("udpsend %d bytes\n", r);
2951 *log_msgptr = string_sprintf("\"udpsend\" failed: %s", errstr);
2957 /*************************************************
2958 * Handle conditions/modifiers on an ACL item *
2959 *************************************************/
2961 /* Called from acl_check() below.
2965 cb ACL condition block - if NULL, result is OK
2966 where where called from
2967 addr the address being checked for RCPT, or NULL
2968 level the nesting level
2969 epp pointer to pass back TRUE if "endpass" encountered
2970 (applies only to "accept" and "discard")
2971 user_msgptr user message pointer
2972 log_msgptr log message pointer
2973 basic_errno pointer to where to put verify error
2975 Returns: OK - all conditions are met
2976 DISCARD - an "acl" condition returned DISCARD - only allowed
2977 for "accept" or "discard" verbs
2978 FAIL - at least one condition fails
2979 FAIL_DROP - an "acl" condition returned FAIL_DROP
2980 DEFER - can't tell at the moment (typically, lookup defer,
2981 but can be temporary callout problem)
2982 ERROR - ERROR from nested ACL or expansion failure or other
2987 acl_check_condition(int verb, acl_condition_block *cb, int where,
2988 address_item *addr, int level, BOOL *epp, uschar **user_msgptr,
2989 uschar **log_msgptr, int *basic_errno)
2991 uschar *user_message = NULL;
2992 uschar *log_message = NULL;
2993 uschar *debug_tag = NULL;
2994 uschar *debug_opts = NULL;
2996 #ifdef WITH_CONTENT_SCAN
3000 for (; cb != NULL; cb = cb->next)
3005 /* The message and log_message items set up messages to be used in
3006 case of rejection. They are expanded later. */
3008 if (cb->type == ACLC_MESSAGE)
3010 HDEBUG(D_acl) debug_printf(" message: %s\n", cb->arg);
3011 user_message = cb->arg;
3015 if (cb->type == ACLC_LOG_MESSAGE)
3017 HDEBUG(D_acl) debug_printf("l_message: %s\n", cb->arg);
3018 log_message = cb->arg;
3022 /* The endpass "condition" just sets a flag to show it occurred. This is
3023 checked at compile time to be on an "accept" or "discard" item. */
3025 if (cb->type == ACLC_ENDPASS)
3031 /* For other conditions and modifiers, the argument is expanded now for some
3032 of them, but not for all, because expansion happens down in some lower level
3033 checking functions in some cases. */
3035 if (cond_expand_at_top[cb->type])
3037 arg = expand_string(cb->arg);
3040 if (expand_string_forcedfail) continue;
3041 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s",
3042 cb->arg, expand_string_message);
3043 return search_find_defer? DEFER : ERROR;
3048 /* Show condition, and expanded condition if it's different */
3053 debug_printf("check %s%s %n",
3054 (!cond_modifiers[cb->type] && cb->u.negated)? "!":"",
3055 conditions[cb->type], &lhswidth);
3057 if (cb->type == ACLC_SET)
3059 debug_printf("acl_%s ", cb->u.varname);
3060 lhswidth += 5 + Ustrlen(cb->u.varname);
3063 debug_printf("= %s\n", cb->arg);
3066 debug_printf("%.*s= %s\n", lhswidth,
3070 /* Check that this condition makes sense at this time */
3072 if ((cond_forbids[cb->type] & (1 << where)) != 0)
3074 *log_msgptr = string_sprintf("cannot %s %s condition in %s ACL",
3075 cond_modifiers[cb->type]? "use" : "test",
3076 conditions[cb->type], acl_wherenames[where]);
3080 /* Run the appropriate test for each condition, or take the appropriate
3081 action for the remaining modifiers. */
3085 case ACLC_ADD_HEADER:
3089 /* A nested ACL that returns "discard" makes sense only for an "accept" or
3093 rc = acl_check_wargs(where, addr, arg, level+1, user_msgptr, log_msgptr);
3094 if (rc == DISCARD && verb != ACL_ACCEPT && verb != ACL_DISCARD)
3096 *log_msgptr = string_sprintf("nested ACL returned \"discard\" for "
3097 "\"%s\" command (only allowed with \"accept\" or \"discard\")",
3103 case ACLC_AUTHENTICATED:
3104 rc = (sender_host_authenticated == NULL)? FAIL :
3105 match_isinlist(sender_host_authenticated, &arg, 0, NULL, NULL, MCL_STRING,
3109 #ifdef EXPERIMENTAL_BRIGHTMAIL
3110 case ACLC_BMI_OPTIN:
3112 int old_pool = store_pool;
3113 store_pool = POOL_PERM;
3114 bmi_current_optin = string_copy(arg);
3115 store_pool = old_pool;
3120 case ACLC_CONDITION:
3121 /* The true/false parsing here should be kept in sync with that used in
3122 expand.c when dealing with ECOND_BOOL so that we don't have too many
3123 different definitions of what can be a boolean. */
3125 ? Ustrspn(arg+1, "0123456789") == Ustrlen(arg+1) /* Negative number */
3126 : Ustrspn(arg, "0123456789") == Ustrlen(arg)) /* Digits, or empty */
3127 rc = (Uatoi(arg) == 0)? FAIL : OK;
3129 rc = (strcmpic(arg, US"no") == 0 ||
3130 strcmpic(arg, US"false") == 0)? FAIL :
3131 (strcmpic(arg, US"yes") == 0 ||
3132 strcmpic(arg, US"true") == 0)? OK : DEFER;
3134 *log_msgptr = string_sprintf("invalid \"condition\" value \"%s\"", arg);
3137 case ACLC_CONTINUE: /* Always succeeds */
3142 const uschar *p = NULL;
3143 control_type = decode_control(arg, &p, where, log_msgptr);
3145 /* Check if this control makes sense at this time */
3147 if ((control_forbids[control_type] & (1 << where)) != 0)
3149 *log_msgptr = string_sprintf("cannot use \"control=%s\" in %s ACL",
3150 controls[control_type], acl_wherenames[where]);
3154 switch(control_type)
3156 case CONTROL_AUTH_UNADVERTISED:
3157 allow_auth_unadvertised = TRUE;
3160 #ifdef EXPERIMENTAL_BRIGHTMAIL
3161 case CONTROL_BMI_RUN:
3166 #ifndef DISABLE_DKIM
3167 case CONTROL_DKIM_VERIFY:
3168 dkim_disable_verify = TRUE;
3169 #ifdef EXPERIMENTAL_DMARC
3170 /* Since DKIM was blocked, skip DMARC too */
3171 dmarc_disable_verify = TRUE;
3172 dmarc_enable_forensic = FALSE;
3177 #ifdef EXPERIMENTAL_DMARC
3178 case CONTROL_DMARC_VERIFY:
3179 dmarc_disable_verify = TRUE;
3182 case CONTROL_DMARC_FORENSIC:
3183 dmarc_enable_forensic = TRUE;
3190 int fd, af, level, optname, value;
3191 /* If we are acting on stdin, the setsockopt may fail if stdin is not
3192 a socket; we can accept that, we'll just debug-log failures anyway. */
3193 fd = fileno(smtp_in);
3194 af = ip_get_address_family(fd);
3198 debug_printf("smtp input is probably not a socket [%s], not setting DSCP\n",
3202 if (dscp_lookup(p+1, af, &level, &optname, &value))
3204 if (setsockopt(fd, level, optname, &value, sizeof(value)) < 0)
3206 HDEBUG(D_acl) debug_printf("failed to set input DSCP[%s]: %s\n",
3207 p+1, strerror(errno));
3211 HDEBUG(D_acl) debug_printf("set input DSCP to \"%s\"\n", p+1);
3216 *log_msgptr = string_sprintf("unrecognised DSCP value in \"control=%s\"", arg);
3222 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3230 case CONTROL_CASEFUL_LOCAL_PART:
3231 deliver_localpart = addr->cc_local_part;
3234 case CONTROL_CASELOWER_LOCAL_PART:
3235 deliver_localpart = addr->lc_local_part;
3238 case CONTROL_ENFORCE_SYNC:
3239 smtp_enforce_sync = TRUE;
3242 case CONTROL_NO_ENFORCE_SYNC:
3243 smtp_enforce_sync = FALSE;
3246 #ifdef WITH_CONTENT_SCAN
3247 case CONTROL_NO_MBOX_UNSPOOL:
3248 no_mbox_unspool = TRUE;
3252 case CONTROL_NO_MULTILINE:
3253 no_multiline_responses = TRUE;
3256 case CONTROL_NO_PIPELINING:
3257 pipelining_enable = FALSE;
3260 case CONTROL_NO_DELAY_FLUSH:
3261 disable_delay_flush = TRUE;
3264 case CONTROL_NO_CALLOUT_FLUSH:
3265 disable_callout_flush = TRUE;
3268 case CONTROL_FAKEREJECT:
3269 cancel_cutthrough_connection("fakereject");
3270 case CONTROL_FAKEDEFER:
3271 fake_response = (control_type == CONTROL_FAKEDEFER) ? DEFER : FAIL;
3274 const uschar *pp = p + 1;
3275 while (*pp != 0) pp++;
3276 fake_response_text = expand_string(string_copyn(p+1, pp-p-1));
3281 /* Explicitly reset to default string */
3282 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).";
3286 case CONTROL_FREEZE:
3287 deliver_freeze = TRUE;
3288 deliver_frozen_at = time(NULL);
3289 freeze_tell = freeze_tell_config; /* Reset to configured value */
3290 if (Ustrncmp(p, "/no_tell", 8) == 0)
3297 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3300 cancel_cutthrough_connection("item frozen");
3303 case CONTROL_QUEUE_ONLY:
3304 queue_only_policy = TRUE;
3305 cancel_cutthrough_connection("queueing forced");
3308 case CONTROL_SUBMISSION:
3309 originator_name = US"";
3310 submission_mode = TRUE;
3313 if (Ustrncmp(p, "/sender_retain", 14) == 0)
3316 active_local_sender_retain = TRUE;
3317 active_local_from_check = FALSE;
3319 else if (Ustrncmp(p, "/domain=", 8) == 0)
3321 const uschar *pp = p + 8;
3322 while (*pp != 0 && *pp != '/') pp++;
3323 submission_domain = string_copyn(p+8, pp-p-8);
3326 /* The name= option must be last, because it swallows the rest of
3328 else if (Ustrncmp(p, "/name=", 6) == 0)
3330 const uschar *pp = p + 6;
3331 while (*pp != 0) pp++;
3332 submission_name = string_copy(parse_fix_phrase(p+6, pp-p-6,
3333 big_buffer, big_buffer_size));
3340 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3348 if (Ustrncmp(p, "/tag=", 5) == 0)
3350 const uschar *pp = p + 5;
3351 while (*pp != '\0' && *pp != '/') pp++;
3352 debug_tag = string_copyn(p+5, pp-p-5);
3355 else if (Ustrncmp(p, "/opts=", 6) == 0)
3357 const uschar *pp = p + 6;
3358 while (*pp != '\0' && *pp != '/') pp++;
3359 debug_opts = string_copyn(p+6, pp-p-6);
3363 debug_logging_activate(debug_tag, debug_opts);
3366 case CONTROL_SUPPRESS_LOCAL_FIXUPS:
3367 suppress_local_fixups = TRUE;
3370 case CONTROL_CUTTHROUGH_DELIVERY:
3372 /* Too hard to think about for now. We might in future cutthrough
3373 the case where both sides handle prdr and this-node prdr acl
3375 *log_msgptr = string_sprintf(US"PRDR on %s reception\n", arg);
3379 *log_msgptr = US"frozen";
3380 else if (queue_only_policy)
3381 *log_msgptr = US"queue-only";
3382 else if (fake_response == FAIL)
3383 *log_msgptr = US"fakereject";
3386 if (rcpt_count == 1) cutthrough.delivery = TRUE;
3389 *log_msgptr = string_sprintf("\"control=%s\" on %s item",
3397 #ifdef EXPERIMENTAL_DCC
3400 /* Seperate the regular expression and any optional parameters. */
3401 const uschar * list = arg;
3402 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
3403 /* Run the dcc backend. */
3404 rc = dcc_process(&ss);
3405 /* Modify return code based upon the existance of options. */
3406 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size))
3408 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
3410 /* FAIL so that the message is passed to the next ACL */
3418 #ifdef WITH_CONTENT_SCAN
3420 rc = mime_decode(&arg);
3426 int delay = readconf_readtime(arg, 0, FALSE);
3429 *log_msgptr = string_sprintf("syntax error in argument for \"delay\" "
3430 "modifier: \"%s\" is not a time value", arg);
3435 HDEBUG(D_acl) debug_printf("delay modifier requests %d-second delay\n",
3440 debug_printf("delay skipped in -bh checking mode\n");
3443 /* It appears to be impossible to detect that a TCP/IP connection has
3444 gone away without reading from it. This means that we cannot shorten
3445 the delay below if the client goes away, because we cannot discover
3446 that the client has closed its end of the connection. (The connection
3447 is actually in a half-closed state, waiting for the server to close its
3448 end.) It would be nice to be able to detect this state, so that the
3449 Exim process is not held up unnecessarily. However, it seems that we
3450 can't. The poll() function does not do the right thing, and in any case
3451 it is not always available.
3453 NOTE 1: If ever this state of affairs changes, remember that we may be
3454 dealing with stdin/stdout here, in addition to TCP/IP connections.
3455 Also, delays may be specified for non-SMTP input, where smtp_out and
3456 smtp_in will be NULL. Whatever is done must work in all cases.
3458 NOTE 2: The added feature of flushing the output before a delay must
3459 apply only to SMTP input. Hence the test for smtp_out being non-NULL.
3464 if (smtp_out != NULL && !disable_delay_flush) mac_smtp_fflush();
3465 while (delay > 0) delay = sleep(delay);
3471 #ifdef WITH_OLD_DEMIME
3477 #ifndef DISABLE_DKIM
3478 case ACLC_DKIM_SIGNER:
3479 if (dkim_cur_signer != NULL)
3480 rc = match_isinlist(dkim_cur_signer,
3481 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
3486 case ACLC_DKIM_STATUS:
3487 rc = match_isinlist(dkim_exim_expand_query(DKIM_VERIFY_STATUS),
3488 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
3492 #ifdef EXPERIMENTAL_DMARC
3493 case ACLC_DMARC_STATUS:
3494 if (!dmarc_has_been_checked)
3496 dmarc_has_been_checked = TRUE;
3497 /* used long way of dmarc_exim_expand_query() in case we need more
3498 * view into the process in the future. */
3499 rc = match_isinlist(dmarc_exim_expand_query(DMARC_VERIFY_STATUS),
3500 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
3505 rc = verify_check_dnsbl(&arg);
3509 rc = match_isinlist(addr->domain, &arg, 0, &domainlist_anchor,
3510 addr->domain_cache, MCL_DOMAIN, TRUE, CUSS &deliver_domain_data);
3513 /* The value in tls_cipher is the full cipher name, for example,
3514 TLSv1:DES-CBC3-SHA:168, whereas the values to test for are just the
3515 cipher names such as DES-CBC3-SHA. But program defensively. We don't know
3516 what may in practice come out of the SSL library - which at the time of
3517 writing is poorly documented. */
3519 case ACLC_ENCRYPTED:
3520 if (tls_in.cipher == NULL) rc = FAIL; else
3522 uschar *endcipher = NULL;
3523 uschar *cipher = Ustrchr(tls_in.cipher, ':');
3524 if (cipher == NULL) cipher = tls_in.cipher; else
3526 endcipher = Ustrchr(++cipher, ':');
3527 if (endcipher != NULL) *endcipher = 0;
3529 rc = match_isinlist(cipher, &arg, 0, NULL, NULL, MCL_STRING, TRUE, NULL);
3530 if (endcipher != NULL) *endcipher = ':';
3534 /* Use verify_check_this_host() instead of verify_check_host() so that
3535 we can pass over &host_data to catch any looked up data. Once it has been
3536 set, it retains its value so that it's still there if another ACL verb
3537 comes through here and uses the cache. However, we must put it into
3538 permanent store in case it is also expected to be used in a subsequent
3539 message in the same SMTP connection. */
3542 rc = verify_check_this_host(&arg, sender_host_cache, NULL,
3543 (sender_host_address == NULL)? US"" : sender_host_address,
3545 if (host_data != NULL) host_data = string_copy_malloc(host_data);
3548 case ACLC_LOCAL_PARTS:
3549 rc = match_isinlist(addr->cc_local_part, &arg, 0,
3550 &localpartlist_anchor, addr->localpart_cache, MCL_LOCALPART, TRUE,
3551 CUSS &deliver_localpart_data);
3554 case ACLC_LOG_REJECT_TARGET:
3558 const uschar *s = arg;
3560 while ((ss = string_nextinlist(&s, &sep, big_buffer, big_buffer_size))
3563 if (Ustrcmp(ss, "main") == 0) logbits |= LOG_MAIN;
3564 else if (Ustrcmp(ss, "panic") == 0) logbits |= LOG_PANIC;
3565 else if (Ustrcmp(ss, "reject") == 0) logbits |= LOG_REJECT;
3568 logbits |= LOG_MAIN|LOG_REJECT;
3569 log_write(0, LOG_MAIN|LOG_PANIC, "unknown log name \"%s\" in "
3570 "\"log_reject_target\" in %s ACL", ss, acl_wherenames[where]);
3573 log_reject_target = logbits;
3580 const uschar *s = arg;
3586 if (Ustrncmp(s, "main", 4) == 0)
3587 { logbits |= LOG_MAIN; s += 4; }
3588 else if (Ustrncmp(s, "panic", 5) == 0)
3589 { logbits |= LOG_PANIC; s += 5; }
3590 else if (Ustrncmp(s, "reject", 6) == 0)
3591 { logbits |= LOG_REJECT; s += 6; }
3594 logbits = LOG_MAIN|LOG_PANIC;
3595 s = string_sprintf(":unknown log name in \"%s\" in "
3596 "\"logwrite\" in %s ACL", arg, acl_wherenames[where]);
3602 while (isspace(*s)) s++;
3605 if (logbits == 0) logbits = LOG_MAIN;
3606 log_write(0, logbits, "%s", string_printing(s));
3610 #ifdef WITH_CONTENT_SCAN
3611 case ACLC_MALWARE: /* Run the malware backend. */
3613 /* Separate the regular expression and any optional parameters. */
3614 const uschar * list = arg;
3615 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
3617 BOOL defer_ok = FALSE;
3620 while ((opt = string_nextinlist(&list, &sep, NULL, 0)))
3621 if (strcmpic(opt, US"defer_ok") == 0)
3623 else if ( strncmpic(opt, US"tmo=", 4) == 0
3624 && (timeout = readconf_readtime(opt+4, '\0', FALSE)) < 0
3627 *log_msgptr = string_sprintf("bad timeout value in '%s'", opt);
3631 rc = malware(ss, timeout);
3632 if (rc == DEFER && defer_ok)
3633 rc = FAIL; /* FAIL so that the message is passed to the next ACL */
3637 case ACLC_MIME_REGEX:
3638 rc = mime_regex(&arg);
3642 case ACLC_RATELIMIT:
3643 rc = acl_ratelimit(arg, where, log_msgptr);
3646 case ACLC_RECIPIENTS:
3647 rc = match_address_list((const uschar *)addr->address, TRUE, TRUE, &arg, NULL, -1, 0,
3648 CUSS &recipient_data);
3651 #ifdef WITH_CONTENT_SCAN
3657 case ACLC_REMOVE_HEADER:
3658 setup_remove_header(arg);
3661 case ACLC_SENDER_DOMAINS:
3664 sdomain = Ustrrchr(sender_address, '@');
3665 sdomain = (sdomain == NULL)? US"" : sdomain + 1;
3666 rc = match_isinlist(sdomain, &arg, 0, &domainlist_anchor,
3667 sender_domain_cache, MCL_DOMAIN, TRUE, NULL);
3672 rc = match_address_list((const uschar *)sender_address, TRUE, TRUE, &arg,
3673 sender_address_cache, -1, 0, CUSS &sender_data);
3676 /* Connection variables must persist forever */
3680 int old_pool = store_pool;
3681 if (cb->u.varname[0] == 'c') store_pool = POOL_PERM;
3682 acl_var_create(cb->u.varname)->data.ptr = string_copy(arg);
3683 store_pool = old_pool;
3687 #ifdef WITH_CONTENT_SCAN
3690 /* Seperate the regular expression and any optional parameters. */
3691 const uschar * list = arg;
3692 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
3693 /* Run the spam backend. */
3694 rc = spam(CUSS &ss);
3695 /* Modify return code based upon the existance of options. */
3696 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size))
3698 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
3700 /* FAIL so that the message is passed to the next ACL */
3708 #ifdef EXPERIMENTAL_SPF
3710 rc = spf_process(&arg, sender_address, SPF_PROCESS_NORMAL);
3712 case ACLC_SPF_GUESS:
3713 rc = spf_process(&arg, sender_address, SPF_PROCESS_GUESS);
3718 rc = acl_udpsend(arg, log_msgptr);
3721 /* If the verb is WARN, discard any user message from verification, because
3722 such messages are SMTP responses, not header additions. The latter come
3723 only from explicit "message" modifiers. However, put the user message into
3724 $acl_verify_message so it can be used in subsequent conditions or modifiers
3725 (until something changes it). */
3728 rc = acl_verify(where, addr, arg, user_msgptr, log_msgptr, basic_errno);
3729 acl_verify_message = *user_msgptr;
3730 if (verb == ACL_WARN) *user_msgptr = NULL;
3734 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown "
3735 "condition %d", cb->type);
3739 /* If a condition was negated, invert OK/FAIL. */
3741 if (!cond_modifiers[cb->type] && cb->u.negated)
3743 if (rc == OK) rc = FAIL;
3744 else if (rc == FAIL || rc == FAIL_DROP) rc = OK;
3747 if (rc != OK) break; /* Conditions loop */
3751 /* If the result is the one for which "message" and/or "log_message" are used,
3752 handle the values of these modifiers. If there isn't a log message set, we make
3753 it the same as the user message.
3755 "message" is a user message that will be included in an SMTP response. Unless
3756 it is empty, it overrides any previously set user message.
3758 "log_message" is a non-user message, and it adds to any existing non-user
3759 message that is already set.
3761 Most verbs have but a single return for which the messages are relevant, but
3762 for "discard", it's useful to have the log message both when it succeeds and
3763 when it fails. For "accept", the message is used in the OK case if there is no
3764 "endpass", but (for backwards compatibility) in the FAIL case if "endpass" is
3767 if (*epp && rc == OK) user_message = NULL;
3769 if (((1<<rc) & msgcond[verb]) != 0)
3772 uschar *old_user_msgptr = *user_msgptr;
3773 uschar *old_log_msgptr = (*log_msgptr != NULL)? *log_msgptr : old_user_msgptr;
3775 /* If the verb is "warn", messages generated by conditions (verification or
3776 nested ACLs) are always discarded. This also happens for acceptance verbs
3777 when they actually do accept. Only messages specified at this level are used.
3778 However, the value of an existing message is available in $acl_verify_message
3779 during expansions. */
3781 if (verb == ACL_WARN ||
3782 (rc == OK && (verb == ACL_ACCEPT || verb == ACL_DISCARD)))
3783 *log_msgptr = *user_msgptr = NULL;
3785 if (user_message != NULL)
3787 acl_verify_message = old_user_msgptr;
3788 expmessage = expand_string(user_message);
3789 if (expmessage == NULL)
3791 if (!expand_string_forcedfail)
3792 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
3793 user_message, expand_string_message);
3795 else if (expmessage[0] != 0) *user_msgptr = expmessage;
3798 if (log_message != NULL)
3800 acl_verify_message = old_log_msgptr;
3801 expmessage = expand_string(log_message);
3802 if (expmessage == NULL)
3804 if (!expand_string_forcedfail)
3805 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
3806 log_message, expand_string_message);
3808 else if (expmessage[0] != 0)
3810 *log_msgptr = (*log_msgptr == NULL)? expmessage :
3811 string_sprintf("%s: %s", expmessage, *log_msgptr);
3815 /* If no log message, default it to the user message */
3817 if (*log_msgptr == NULL) *log_msgptr = *user_msgptr;
3820 acl_verify_message = NULL;
3828 /*************************************************
3829 * Get line from a literal ACL *
3830 *************************************************/
3832 /* This function is passed to acl_read() in order to extract individual lines
3833 of a literal ACL, which we access via static pointers. We can destroy the
3834 contents because this is called only once (the compiled ACL is remembered).
3836 This code is intended to treat the data in the same way as lines in the main
3837 Exim configuration file. That is:
3839 . Leading spaces are ignored.
3841 . A \ at the end of a line is a continuation - trailing spaces after the \
3842 are permitted (this is because I don't believe in making invisible things
3843 significant). Leading spaces on the continued part of a line are ignored.
3845 . Physical lines starting (significantly) with # are totally ignored, and
3846 may appear within a sequence of backslash-continued lines.
3848 . Blank lines are ignored, but will end a sequence of continuations.
3851 Returns: a pointer to the next line
3855 static uschar *acl_text; /* Current pointer in the text */
3856 static uschar *acl_text_end; /* Points one past the terminating '0' */
3864 /* This loop handles leading blank lines and comments. */
3868 while (isspace(*acl_text)) acl_text++; /* Leading spaces/empty lines */
3869 if (*acl_text == 0) return NULL; /* No more data */
3870 yield = acl_text; /* Potential data line */
3872 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3874 /* If we hit the end before a newline, we have the whole logical line. If
3875 it's a comment, there's no more data to be given. Otherwise, yield it. */
3877 if (*acl_text == 0) return (*yield == '#')? NULL : yield;
3879 /* After reaching a newline, end this loop if the physical line does not
3880 start with '#'. If it does, it's a comment, and the loop continues. */
3882 if (*yield != '#') break;
3885 /* This loop handles continuations. We know we have some real data, ending in
3886 newline. See if there is a continuation marker at the end (ignoring trailing
3887 white space). We know that *yield is not white space, so no need to test for
3888 cont > yield in the backwards scanning loop. */
3893 for (cont = acl_text - 1; isspace(*cont); cont--);
3895 /* If no continuation follows, we are done. Mark the end of the line and
3904 /* We have encountered a continuation. Skip over whitespace at the start of
3905 the next line, and indeed the whole of the next line or lines if they are
3910 while (*(++acl_text) == ' ' || *acl_text == '\t');
3911 if (*acl_text != '#') break;
3912 while (*(++acl_text) != 0 && *acl_text != '\n');
3915 /* We have the start of a continuation line. Move all the rest of the data
3916 to join onto the previous line, and then find its end. If the end is not a
3917 newline, we are done. Otherwise loop to look for another continuation. */
3919 memmove(cont, acl_text, acl_text_end - acl_text);
3920 acl_text_end -= acl_text - cont;
3922 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3923 if (*acl_text == 0) return yield;
3926 /* Control does not reach here */
3933 /*************************************************
3934 * Check access using an ACL *
3935 *************************************************/
3937 /* This function is called from address_check. It may recurse via
3938 acl_check_condition() - hence the use of a level to stop looping. The ACL is
3939 passed as a string which is expanded. A forced failure implies no access check
3940 is required. If the result is a single word, it is taken as the name of an ACL
3941 which is sought in the global ACL tree. Otherwise, it is taken as literal ACL
3942 text, complete with newlines, and parsed as such. In both cases, the ACL check
3943 is then run. This function uses an auxiliary function for acl_read() to call
3944 for reading individual lines of a literal ACL. This is acl_getline(), which
3945 appears immediately above.
3948 where where called from
3949 addr address item when called from RCPT; otherwise NULL
3950 s the input string; NULL is the same as an empty ACL => DENY
3951 level the nesting level
3952 user_msgptr where to put a user error (for SMTP response)
3953 log_msgptr where to put a logging message (not for SMTP response)
3955 Returns: OK access is granted
3956 DISCARD access is apparently granted...
3957 FAIL access is denied
3958 FAIL_DROP access is denied; drop the connection
3959 DEFER can't tell at the moment
3964 acl_check_internal(int where, address_item *addr, uschar *s, int level,
3965 uschar **user_msgptr, uschar **log_msgptr)
3968 acl_block *acl = NULL;
3969 uschar *acl_name = US"inline ACL";
3972 /* Catch configuration loops */
3976 *log_msgptr = US"ACL nested too deep: possible loop";
3982 HDEBUG(D_acl) debug_printf("ACL is NULL: implicit DENY\n");
3986 /* At top level, we expand the incoming string. At lower levels, it has already
3987 been expanded as part of condition processing. */
3991 ss = expand_string(s);
3994 if (expand_string_forcedfail) return OK;
3995 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s", s,
3996 expand_string_message);
4002 while (isspace(*ss))ss++;
4004 /* If we can't find a named ACL, the default is to parse it as an inline one.
4005 (Unless it begins with a slash; non-existent files give rise to an error.) */
4009 /* Handle the case of a string that does not contain any spaces. Look for a
4010 named ACL among those read from the configuration, or a previously read file.
4011 It is possible that the pointer to the ACL is NULL if the configuration
4012 contains a name with no data. If not found, and the text begins with '/',
4013 read an ACL from a file, and save it so it can be re-used. */
4015 if (Ustrchr(ss, ' ') == NULL)
4017 tree_node *t = tree_search(acl_anchor, ss);
4020 acl = (acl_block *)(t->data.ptr);
4023 HDEBUG(D_acl) debug_printf("ACL \"%s\" is empty: implicit DENY\n", ss);
4026 acl_name = string_sprintf("ACL \"%s\"", ss);
4027 HDEBUG(D_acl) debug_printf("using ACL \"%s\"\n", ss);
4030 else if (*ss == '/')
4032 struct stat statbuf;
4033 fd = Uopen(ss, O_RDONLY, 0);
4036 *log_msgptr = string_sprintf("failed to open ACL file \"%s\": %s", ss,
4041 if (fstat(fd, &statbuf) != 0)
4043 *log_msgptr = string_sprintf("failed to fstat ACL file \"%s\": %s", ss,
4048 acl_text = store_get(statbuf.st_size + 1);
4049 acl_text_end = acl_text + statbuf.st_size + 1;
4051 if (read(fd, acl_text, statbuf.st_size) != statbuf.st_size)
4053 *log_msgptr = string_sprintf("failed to read ACL file \"%s\": %s",
4054 ss, strerror(errno));
4057 acl_text[statbuf.st_size] = 0;
4060 acl_name = string_sprintf("ACL \"%s\"", ss);
4061 HDEBUG(D_acl) debug_printf("read ACL from file %s\n", ss);
4065 /* Parse an ACL that is still in text form. If it came from a file, remember it
4066 in the ACL tree, having read it into the POOL_PERM store pool so that it
4067 persists between multiple messages. */
4071 int old_pool = store_pool;
4072 if (fd >= 0) store_pool = POOL_PERM;
4073 acl = acl_read(acl_getline, log_msgptr);
4074 store_pool = old_pool;
4075 if (acl == NULL && *log_msgptr != NULL) return ERROR;
4078 tree_node *t = store_get_perm(sizeof(tree_node) + Ustrlen(ss));
4079 Ustrcpy(t->name, ss);
4081 (void)tree_insertnode(&acl_anchor, t);
4085 /* Now we have an ACL to use. It's possible it may be NULL. */
4090 int basic_errno = 0;
4091 BOOL endpass_seen = FALSE;
4093 *log_msgptr = *user_msgptr = NULL;
4094 acl_temp_details = FALSE;
4096 if ((where == ACL_WHERE_QUIT || where == ACL_WHERE_NOTQUIT) &&
4097 acl->verb != ACL_ACCEPT &&
4098 acl->verb != ACL_WARN)
4100 *log_msgptr = string_sprintf("\"%s\" is not allowed in a QUIT or not-QUIT ACL",
4105 HDEBUG(D_acl) debug_printf("processing \"%s\"\n", verbs[acl->verb]);
4107 /* Clear out any search error message from a previous check before testing
4110 search_error_message = NULL;
4111 cond = acl_check_condition(acl->verb, acl->condition, where, addr, level,
4112 &endpass_seen, user_msgptr, log_msgptr, &basic_errno);
4114 /* Handle special returns: DEFER causes a return except on a WARN verb;
4115 ERROR always causes a return. */
4120 HDEBUG(D_acl) debug_printf("%s: condition test deferred in %s\n", verbs[acl->verb], acl_name);
4121 if (basic_errno != ERRNO_CALLOUTDEFER)
4123 if (search_error_message != NULL && *search_error_message != 0)
4124 *log_msgptr = search_error_message;
4125 if (smtp_return_error_details) acl_temp_details = TRUE;
4129 acl_temp_details = TRUE;
4131 if (acl->verb != ACL_WARN) return DEFER;
4134 default: /* Paranoia */
4136 HDEBUG(D_acl) debug_printf("%s: condition test error in %s\n", verbs[acl->verb], acl_name);
4140 HDEBUG(D_acl) debug_printf("%s: condition test succeeded in %s\n",
4141 verbs[acl->verb], acl_name);
4145 HDEBUG(D_acl) debug_printf("%s: condition test failed in %s\n", verbs[acl->verb], acl_name);
4148 /* DISCARD and DROP can happen only from a nested ACL condition, and
4149 DISCARD can happen only for an "accept" or "discard" verb. */
4152 HDEBUG(D_acl) debug_printf("%s: condition test yielded \"discard\" in %s\n",
4153 verbs[acl->verb], acl_name);
4157 HDEBUG(D_acl) debug_printf("%s: condition test yielded \"drop\" in %s\n",
4158 verbs[acl->verb], acl_name);
4162 /* At this point, cond for most verbs is either OK or FAIL or (as a result of
4163 a nested ACL condition) FAIL_DROP. However, for WARN, cond may be DEFER, and
4164 for ACCEPT and DISCARD, it may be DISCARD after a nested ACL call. */
4169 if (cond == OK || cond == DISCARD)
4171 HDEBUG(D_acl) debug_printf("end of %s: ACCEPT\n", acl_name);
4176 HDEBUG(D_acl) debug_printf("accept: endpass encountered - denying access\n");
4184 HDEBUG(D_acl) debug_printf("end of %s: DEFER\n", acl_name);
4185 acl_temp_details = TRUE;
4193 HDEBUG(D_acl) debug_printf("end of %s: DENY\n", acl_name);
4199 if (cond == OK || cond == DISCARD)
4201 HDEBUG(D_acl) debug_printf("end of %s: DISCARD\n", acl_name);
4206 HDEBUG(D_acl) debug_printf("discard: endpass encountered - denying access\n");
4214 HDEBUG(D_acl) debug_printf("end of %s: DROP\n", acl_name);
4222 HDEBUG(D_acl) debug_printf("end of %s: not OK\n", acl_name);
4229 acl_warn(where, *user_msgptr, *log_msgptr);
4230 else if (cond == DEFER && (log_extra_selector & LX_acl_warn_skipped) != 0)
4231 log_write(0, LOG_MAIN, "%s Warning: ACL \"warn\" statement skipped: "
4232 "condition test deferred%s%s", host_and_ident(TRUE),
4233 (*log_msgptr == NULL)? US"" : US": ",
4234 (*log_msgptr == NULL)? US"" : *log_msgptr);
4235 *log_msgptr = *user_msgptr = NULL; /* In case implicit DENY follows */
4239 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown verb %d",
4244 /* Pass to the next ACL item */
4249 /* We have reached the end of the ACL. This is an implicit DENY. */
4251 HDEBUG(D_acl) debug_printf("end of %s: implicit DENY\n", acl_name);
4258 /* Same args as acl_check_internal() above, but the string s is
4259 the name of an ACL followed optionally by up to 9 space-separated arguments.
4260 The name and args are separately expanded. Args go into $acl_arg globals. */
4262 acl_check_wargs(int where, address_item *addr, const uschar *s, int level,
4263 uschar **user_msgptr, uschar **log_msgptr)
4266 uschar * tmp_arg[9]; /* must match acl_arg[] */
4267 uschar * sav_arg[9]; /* must match acl_arg[] */
4273 if (!(tmp = string_dequote(&s)) || !(name = expand_string(tmp)))
4276 for (i = 0; i < 9; i++)
4278 while (*s && isspace(*s)) s++;
4280 if (!(tmp = string_dequote(&s)) || !(tmp_arg[i] = expand_string(tmp)))
4287 sav_narg = acl_narg;
4289 for (i = 0; i < acl_narg; i++)
4291 sav_arg[i] = acl_arg[i];
4292 acl_arg[i] = tmp_arg[i];
4296 sav_arg[i] = acl_arg[i];
4297 acl_arg[i++] = NULL;
4300 ret = acl_check_internal(where, addr, name, level, user_msgptr, log_msgptr);
4302 acl_narg = sav_narg;
4303 for (i = 0; i < 9; i++) acl_arg[i] = sav_arg[i];
4307 if (expand_string_forcedfail) return ERROR;
4308 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s",
4309 tmp, expand_string_message);
4310 return search_find_defer?DEFER:ERROR;
4315 /*************************************************
4316 * Check access using an ACL *
4317 *************************************************/
4319 /* Alternate interface for ACL, used by expansions */
4321 acl_eval(int where, uschar *s, uschar **user_msgptr, uschar **log_msgptr)
4324 address_item *addr = NULL;
4326 *user_msgptr = *log_msgptr = NULL;
4327 sender_verified_failed = NULL;
4328 ratelimiters_cmd = NULL;
4329 log_reject_target = LOG_MAIN|LOG_REJECT;
4331 if (where == ACL_WHERE_RCPT)
4333 adb = address_defaults;
4335 addr->address = expand_string(US"$local_part@$domain");
4336 addr->domain = deliver_domain;
4337 addr->local_part = deliver_localpart;
4338 addr->cc_local_part = deliver_localpart;
4339 addr->lc_local_part = deliver_localpart;
4342 return acl_check_internal(where, addr, s, 0, user_msgptr, log_msgptr);
4347 /* This is the external interface for ACL checks. It sets up an address and the
4348 expansions for $domain and $local_part when called after RCPT, then calls
4349 acl_check_internal() to do the actual work.
4352 where ACL_WHERE_xxxx indicating where called from
4353 recipient RCPT address for RCPT check, else NULL
4354 s the input string; NULL is the same as an empty ACL => DENY
4355 user_msgptr where to put a user error (for SMTP response)
4356 log_msgptr where to put a logging message (not for SMTP response)
4358 Returns: OK access is granted by an ACCEPT verb
4359 DISCARD access is granted by a DISCARD verb
4360 FAIL access is denied
4361 FAIL_DROP access is denied; drop the connection
4362 DEFER can't tell at the moment
4365 int acl_where = ACL_WHERE_UNKNOWN;
4368 acl_check(int where, uschar *recipient, uschar *s, uschar **user_msgptr,
4369 uschar **log_msgptr)
4373 address_item *addr = NULL;
4375 *user_msgptr = *log_msgptr = NULL;
4376 sender_verified_failed = NULL;
4377 ratelimiters_cmd = NULL;
4378 log_reject_target = LOG_MAIN|LOG_REJECT;
4380 #ifndef DISABLE_PRDR
4381 if (where == ACL_WHERE_RCPT || where == ACL_WHERE_PRDR)
4383 if (where == ACL_WHERE_RCPT)
4386 adb = address_defaults;
4388 addr->address = recipient;
4389 if (deliver_split_address(addr) == DEFER)
4391 *log_msgptr = US"defer in percent_hack_domains check";
4394 deliver_domain = addr->domain;
4395 deliver_localpart = addr->local_part;
4399 rc = acl_check_internal(where, addr, s, 0, user_msgptr, log_msgptr);
4400 acl_where = ACL_WHERE_UNKNOWN;
4402 /* Cutthrough - if requested,
4403 and WHERE_RCPT and not yet opened conn as result of recipient-verify,
4404 and rcpt acl returned accept,
4405 and first recipient (cancel on any subsequents)
4406 open one now and run it up to RCPT acceptance.
4407 A failed verify should cancel cutthrough request.
4409 Initial implementation: dual-write to spool.
4410 Assume the rxd datastream is now being copied byte-for-byte to an open cutthrough connection.
4412 Cease cutthrough copy on rxd final dot; do not send one.
4414 On a data acl, if not accept and a cutthrough conn is open, hard-close it (no SMTP niceness).
4416 On data acl accept, terminate the dataphase on an open cutthrough conn. If accepted or
4417 perm-rejected, reflect that to the original sender - and dump the spooled copy.
4418 If temp-reject, close the conn (and keep the spooled copy).
4419 If conn-failure, no action (and keep the spooled copy).
4423 case ACL_WHERE_RCPT:
4424 #ifndef DISABLE_PRDR
4425 case ACL_WHERE_PRDR:
4427 if (rc == OK && cutthrough.delivery && rcpt_count > cutthrough.nrcpt)
4428 open_cutthrough_connection(addr);
4431 case ACL_WHERE_PREDATA:
4433 cutthrough_predata();
4435 cancel_cutthrough_connection("predata acl not ok");
4438 case ACL_WHERE_QUIT:
4439 case ACL_WHERE_NOTQUIT:
4440 cancel_cutthrough_connection("quit or notquit");
4447 deliver_domain = deliver_localpart = deliver_address_data =
4448 sender_address_data = NULL;
4450 /* A DISCARD response is permitted only for message ACLs, excluding the PREDATA
4451 ACL, which is really in the middle of an SMTP command. */
4455 if (where > ACL_WHERE_NOTSMTP || where == ACL_WHERE_PREDATA)
4457 log_write(0, LOG_MAIN|LOG_PANIC, "\"discard\" verb not allowed in %s "
4458 "ACL", acl_wherenames[where]);
4464 /* A DROP response is not permitted from MAILAUTH */
4466 if (rc == FAIL_DROP && where == ACL_WHERE_MAILAUTH)
4468 log_write(0, LOG_MAIN|LOG_PANIC, "\"drop\" verb not allowed in %s "
4469 "ACL", acl_wherenames[where]);
4473 /* Before giving a response, take a look at the length of any user message, and
4474 split it up into multiple lines if possible. */
4476 *user_msgptr = string_split_message(*user_msgptr);
4477 if (fake_response != OK)
4478 fake_response_text = string_split_message(fake_response_text);
4484 /*************************************************
4485 * Create ACL variable *
4486 *************************************************/
4488 /* Create an ACL variable or reuse an existing one. ACL variables are in a
4489 binary tree (see tree.c) with acl_var_c and acl_var_m as root nodes.
4492 name pointer to the variable's name, starting with c or m
4494 Returns the pointer to variable's tree node
4498 acl_var_create(uschar *name)
4500 tree_node *node, **root;
4501 root = (name[0] == 'c')? &acl_var_c : &acl_var_m;
4502 node = tree_search(*root, name);
4505 node = store_get(sizeof(tree_node) + Ustrlen(name));
4506 Ustrcpy(node->name, name);
4507 (void)tree_insertnode(root, node);
4509 node->data.ptr = NULL;
4515 /*************************************************
4516 * Write an ACL variable in spool format *
4517 *************************************************/
4519 /* This function is used as a callback for tree_walk when writing variables to
4520 the spool file. To retain spool file compatibility, what is written is -aclc or
4521 -aclm followed by the rest of the name and the data length, space separated,
4522 then the value itself, starting on a new line, and terminated by an additional
4523 newline. When we had only numbered ACL variables, the first line might look
4524 like this: "-aclc 5 20". Now it might be "-aclc foo 20" for the variable called
4528 name of the variable
4529 value of the variable
4530 ctx FILE pointer (as a void pointer)
4536 acl_var_write(uschar *name, uschar *value, void *ctx)
4538 FILE *f = (FILE *)ctx;
4539 fprintf(f, "-acl%c %s %d\n%s\n", name[0], name+1, Ustrlen(value), value);