1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2016 */
6 /* See the file NOTICE for conditions of use and distribution. */
8 /* Code for handling Access Control Lists (ACLs) */
13 /* Default callout timeout */
15 #define CALLOUT_TIMEOUT_DEFAULT 30
17 /* ACL verb codes - keep in step with the table of verbs that follows */
19 enum { ACL_ACCEPT, ACL_DEFER, ACL_DENY, ACL_DISCARD, ACL_DROP, ACL_REQUIRE,
24 static uschar *verbs[] = {
33 /* For each verb, the conditions for which "message" or "log_message" are used
34 are held as a bitmap. This is to avoid expanding the strings unnecessarily. For
35 "accept", the FAIL case is used only after "endpass", but that is selected in
38 static int msgcond[] = {
39 (1<<OK) | (1<<FAIL) | (1<<FAIL_DROP), /* accept */
42 (1<<OK) | (1<<FAIL) | (1<<FAIL_DROP), /* discard */
44 (1<<FAIL) | (1<<FAIL_DROP), /* require */
48 /* ACL condition and modifier codes - keep in step with the table that
49 follows, and the cond_expand_at_top and uschar cond_modifiers tables lower
55 #ifdef EXPERIMENTAL_BRIGHTMAIL
61 #ifdef EXPERIMENTAL_DCC
64 #ifdef WITH_CONTENT_SCAN
72 #ifdef EXPERIMENTAL_DMARC
82 ACLC_LOG_REJECT_TARGET,
84 #ifdef WITH_CONTENT_SCAN
88 #ifdef WITH_CONTENT_SCAN
93 #ifdef WITH_CONTENT_SCAN
100 #ifdef WITH_CONTENT_SCAN
103 #ifdef EXPERIMENTAL_SPF
110 /* ACL conditions/modifiers: "delay", "control", "continue", "endpass",
111 "message", "log_message", "log_reject_target", "logwrite", and "set" are
112 modifiers that look like conditions but always return TRUE. They are used for
113 their side effects. */
115 static uschar *conditions[] = {
119 #ifdef EXPERIMENTAL_BRIGHTMAIL
125 #ifdef EXPERIMENTAL_DCC
128 #ifdef WITH_CONTENT_SCAN
136 #ifdef EXPERIMENTAL_DMARC
146 US"log_reject_target",
148 #ifdef WITH_CONTENT_SCAN
152 #ifdef WITH_CONTENT_SCAN
157 #ifdef WITH_CONTENT_SCAN
161 US"sender_domains", US"senders", US"set",
162 #ifdef WITH_CONTENT_SCAN
165 #ifdef EXPERIMENTAL_SPF
173 /* Return values from decode_control(); keep in step with the table of names
177 CONTROL_AUTH_UNADVERTISED,
178 #ifdef EXPERIMENTAL_BRIGHTMAIL
185 #ifdef EXPERIMENTAL_DMARC
186 CONTROL_DMARC_VERIFY,
187 CONTROL_DMARC_FORENSIC,
191 CONTROL_CASEFUL_LOCAL_PART,
192 CONTROL_CASELOWER_LOCAL_PART,
193 CONTROL_CUTTHROUGH_DELIVERY,
194 CONTROL_ENFORCE_SYNC,
195 CONTROL_NO_ENFORCE_SYNC,
199 CONTROL_SUPPRESS_LOCAL_FIXUPS,
200 #ifdef WITH_CONTENT_SCAN
201 CONTROL_NO_MBOX_UNSPOOL,
206 CONTROL_UTF8_DOWNCONVERT,
208 CONTROL_NO_MULTILINE,
209 CONTROL_NO_PIPELINING,
210 CONTROL_NO_DELAY_FLUSH,
211 CONTROL_NO_CALLOUT_FLUSH
214 /* ACL control names; keep in step with the table above! This list is used for
215 turning ids into names. The actual list of recognized names is in the variable
216 control_def controls_list[] below. The fact that there are two lists is a mess
217 and should be tidied up. */
219 static uschar *controls[] = {
220 US"allow_auth_unadvertised",
221 #ifdef EXPERIMENTAL_BRIGHTMAIL
226 US"dkim_disable_verify",
228 #ifdef EXPERIMENTAL_DMARC
229 US"dmarc_disable_verify",
230 US"dmarc_enable_forensic",
234 US"caseful_local_part",
235 US"caselower_local_part",
236 US"cutthrough_delivery",
242 US"suppress_local_fixups",
243 #ifdef WITH_CONTENT_SCAN
249 US"utf8_downconvert",
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
279 TRUE, /* dkim_signers */
280 TRUE, /* dkim_status */
282 #ifdef EXPERIMENTAL_DMARC
283 TRUE, /* dmarc_status */
287 FALSE, /* encrypted */
290 FALSE, /* local_parts */
291 TRUE, /* log_message */
292 TRUE, /* log_reject_target */
294 #ifdef WITH_CONTENT_SCAN
298 #ifdef WITH_CONTENT_SCAN
299 TRUE, /* mime_regex */
301 TRUE, /* ratelimit */
302 FALSE, /* recipients */
303 #ifdef WITH_CONTENT_SCAN
306 TRUE, /* remove_header */
307 FALSE, /* sender_domains */
310 #ifdef WITH_CONTENT_SCAN
313 #ifdef EXPERIMENTAL_SPF
315 TRUE, /* spf_guess */
321 /* Flags to identify the modifiers */
323 static uschar cond_modifiers[] = {
325 TRUE, /* add_header */
326 FALSE, /* authenticated */
327 #ifdef EXPERIMENTAL_BRIGHTMAIL
328 TRUE, /* bmi_optin */
330 FALSE, /* condition */
333 #ifdef EXPERIMENTAL_DCC
336 #ifdef WITH_CONTENT_SCAN
341 FALSE, /* dkim_signers */
342 FALSE, /* dkim_status */
344 #ifdef EXPERIMENTAL_DMARC
345 FALSE, /* dmarc_status */
347 FALSE, /* dnslists */
349 FALSE, /* encrypted */
352 FALSE, /* local_parts */
353 TRUE, /* log_message */
354 TRUE, /* log_reject_target */
356 #ifdef WITH_CONTENT_SCAN
360 #ifdef WITH_CONTENT_SCAN
361 FALSE, /* mime_regex */
363 FALSE, /* ratelimit */
364 FALSE, /* recipients */
365 #ifdef WITH_CONTENT_SCAN
368 TRUE, /* remove_header */
369 FALSE, /* sender_domains */
372 #ifdef WITH_CONTENT_SCAN
375 #ifdef EXPERIMENTAL_SPF
377 FALSE, /* spf_guess */
383 /* Bit map vector of which conditions and modifiers are not allowed at certain
384 times. For each condition and modifier, there's a bitmap of dis-allowed times.
385 For some, it is easier to specify the negation of a small number of allowed
388 static unsigned int cond_forbids[] = {
392 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* add_header */
393 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
397 (1<<ACL_WHERE_MIME)|(1<<ACL_WHERE_NOTSMTP)|
399 (1<<ACL_WHERE_NOTSMTP_START)),
401 (1<<ACL_WHERE_NOTSMTP)| /* authenticated */
402 (1<<ACL_WHERE_NOTSMTP_START)|
403 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO),
405 #ifdef EXPERIMENTAL_BRIGHTMAIL
406 (1<<ACL_WHERE_AUTH)| /* bmi_optin */
407 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
408 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_MIME)|
412 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
413 (1<<ACL_WHERE_MAILAUTH)|
414 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
415 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_PREDATA)|
416 (1<<ACL_WHERE_NOTSMTP_START),
423 /* Certain types of control are always allowed, so we let it through
424 always and check in the control processing itself. */
428 #ifdef EXPERIMENTAL_DCC
430 ~((1<<ACL_WHERE_DATA)| /* dcc */
434 (1<<ACL_WHERE_NOTSMTP)),
437 #ifdef WITH_CONTENT_SCAN
439 ~(1<<ACL_WHERE_MIME), /* decode */
442 (1<<ACL_WHERE_NOTQUIT), /* delay */
446 ~(1<<ACL_WHERE_DKIM), /* dkim_signers */
449 ~(1<<ACL_WHERE_DKIM), /* dkim_status */
452 #ifdef EXPERIMENTAL_DMARC
454 ~(1<<ACL_WHERE_DATA), /* dmarc_status */
457 /* Explicit key lookups can be made in non-smtp ACLs so pass
458 always and check in the verify processing itself. */
463 ~((1<<ACL_WHERE_RCPT) /* domains */
470 (1<<ACL_WHERE_NOTSMTP)| /* encrypted */
471 (1<<ACL_WHERE_CONNECT)|
472 (1<<ACL_WHERE_NOTSMTP_START)|
477 (1<<ACL_WHERE_NOTSMTP)| /* hosts */
478 (1<<ACL_WHERE_NOTSMTP_START),
481 ~((1<<ACL_WHERE_RCPT) /* local_parts */
490 0, /* log_reject_target */
494 #ifdef WITH_CONTENT_SCAN
496 ~((1<<ACL_WHERE_DATA)| /* malware */
500 (1<<ACL_WHERE_NOTSMTP)),
505 #ifdef WITH_CONTENT_SCAN
507 ~(1<<ACL_WHERE_MIME), /* mime_regex */
513 ~(1<<ACL_WHERE_RCPT), /* recipients */
515 #ifdef WITH_CONTENT_SCAN
517 ~((1<<ACL_WHERE_DATA)| /* regex */
521 (1<<ACL_WHERE_NOTSMTP)|
522 (1<<ACL_WHERE_MIME)),
526 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* remove_header */
527 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
531 (1<<ACL_WHERE_MIME)|(1<<ACL_WHERE_NOTSMTP)|
532 (1<<ACL_WHERE_NOTSMTP_START)),
534 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* sender_domains */
536 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
537 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
538 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
540 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* senders */
542 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
543 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
544 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
548 #ifdef WITH_CONTENT_SCAN
550 ~((1<<ACL_WHERE_DATA)| /* spam */
554 (1<<ACL_WHERE_NOTSMTP)),
557 #ifdef EXPERIMENTAL_SPF
558 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* spf */
560 (1<<ACL_WHERE_MAILAUTH)|
561 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
562 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY)|
563 (1<<ACL_WHERE_NOTSMTP)|
564 (1<<ACL_WHERE_NOTSMTP_START),
566 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* spf_guess */
568 (1<<ACL_WHERE_MAILAUTH)|
569 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
570 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY)|
571 (1<<ACL_WHERE_NOTSMTP)|
572 (1<<ACL_WHERE_NOTSMTP_START),
577 /* Certain types of verify are always allowed, so we let it through
578 always and check in the verify function itself */
584 /* Bit map vector of which controls are not allowed at certain times. For
585 each control, there's a bitmap of dis-allowed times. For some, it is easier to
586 specify the negation of a small number of allowed times. */
588 static unsigned int control_forbids[] = {
590 ~((1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)), /* allow_auth_unadvertised */
592 #ifdef EXPERIMENTAL_BRIGHTMAIL
599 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* dkim_disable_verify */
600 # ifndef DISABLE_PRDR
603 (1<<ACL_WHERE_NOTSMTP_START),
606 #ifdef EXPERIMENTAL_DMARC
607 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* dmarc_disable_verify */
608 (1<<ACL_WHERE_NOTSMTP_START),
609 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* dmarc_enable_forensic */
610 (1<<ACL_WHERE_NOTSMTP_START),
613 (1<<ACL_WHERE_NOTSMTP)|
614 (1<<ACL_WHERE_NOTSMTP_START)|
615 (1<<ACL_WHERE_NOTQUIT), /* dscp */
620 ~(1<<ACL_WHERE_RCPT), /* caseful_local_part */
623 ~(1<<ACL_WHERE_RCPT), /* caselower_local_part */
626 0, /* cutthrough_delivery */
628 (1<<ACL_WHERE_NOTSMTP)| /* enforce_sync */
629 (1<<ACL_WHERE_NOTSMTP_START),
631 (1<<ACL_WHERE_NOTSMTP)| /* no_enforce_sync */
632 (1<<ACL_WHERE_NOTSMTP_START),
635 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* freeze */
636 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
637 // (1<<ACL_WHERE_PRDR)| /* Not allow one user to freeze for all */
638 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)),
641 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* queue_only */
642 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
643 // (1<<ACL_WHERE_PRDR)| /* Not allow one user to freeze for all */
644 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)),
647 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* submission */
648 (1<<ACL_WHERE_PREDATA)),
651 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* suppress_local_fixups */
652 (1<<ACL_WHERE_PREDATA)|
653 (1<<ACL_WHERE_NOTSMTP_START)),
655 #ifdef WITH_CONTENT_SCAN
657 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* no_mbox_unspool */
658 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
659 // (1<<ACL_WHERE_PRDR)| /* Not allow one user to freeze for all */
660 (1<<ACL_WHERE_MIME)),
664 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakedefer */
665 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
669 (1<<ACL_WHERE_MIME)),
672 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakereject */
673 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
677 (1<<ACL_WHERE_MIME)),
680 0, /* utf8_downconvert */
683 (1<<ACL_WHERE_NOTSMTP)| /* no_multiline */
684 (1<<ACL_WHERE_NOTSMTP_START),
686 (1<<ACL_WHERE_NOTSMTP)| /* no_pipelining */
687 (1<<ACL_WHERE_NOTSMTP_START),
689 (1<<ACL_WHERE_NOTSMTP)| /* no_delay_flush */
690 (1<<ACL_WHERE_NOTSMTP_START),
692 (1<<ACL_WHERE_NOTSMTP)| /* no_callout_flush */
693 (1<<ACL_WHERE_NOTSMTP_START)
696 /* Structure listing various control arguments, with their characteristics. */
698 typedef struct control_def {
700 int value; /* CONTROL_xxx value */
701 BOOL has_option; /* Has /option(s) following */
704 static control_def controls_list[] = {
705 { US"allow_auth_unadvertised", CONTROL_AUTH_UNADVERTISED, FALSE },
706 #ifdef EXPERIMENTAL_BRIGHTMAIL
707 { US"bmi_run", CONTROL_BMI_RUN, FALSE },
709 { US"debug", CONTROL_DEBUG, TRUE },
711 { US"dkim_disable_verify", CONTROL_DKIM_VERIFY, FALSE },
713 #ifdef EXPERIMENTAL_DMARC
714 { US"dmarc_disable_verify", CONTROL_DMARC_VERIFY, FALSE },
715 { US"dmarc_enable_forensic", CONTROL_DMARC_FORENSIC, FALSE },
717 { US"dscp", CONTROL_DSCP, TRUE },
718 { US"caseful_local_part", CONTROL_CASEFUL_LOCAL_PART, FALSE },
719 { US"caselower_local_part", CONTROL_CASELOWER_LOCAL_PART, FALSE },
720 { US"enforce_sync", CONTROL_ENFORCE_SYNC, FALSE },
721 { US"freeze", CONTROL_FREEZE, TRUE },
722 { US"no_callout_flush", CONTROL_NO_CALLOUT_FLUSH, FALSE },
723 { US"no_delay_flush", CONTROL_NO_DELAY_FLUSH, FALSE },
724 { US"no_enforce_sync", CONTROL_NO_ENFORCE_SYNC, FALSE },
725 { US"no_multiline_responses", CONTROL_NO_MULTILINE, FALSE },
726 { US"no_pipelining", CONTROL_NO_PIPELINING, FALSE },
727 { US"queue_only", CONTROL_QUEUE_ONLY, FALSE },
728 #ifdef WITH_CONTENT_SCAN
729 { US"no_mbox_unspool", CONTROL_NO_MBOX_UNSPOOL, FALSE },
731 { US"fakedefer", CONTROL_FAKEDEFER, TRUE },
732 { US"fakereject", CONTROL_FAKEREJECT, TRUE },
733 { US"submission", CONTROL_SUBMISSION, TRUE },
734 { US"suppress_local_fixups", CONTROL_SUPPRESS_LOCAL_FIXUPS, FALSE },
735 { US"cutthrough_delivery", CONTROL_CUTTHROUGH_DELIVERY, FALSE },
737 { US"utf8_downconvert", CONTROL_UTF8_DOWNCONVERT, TRUE }
741 /* Support data structures for Client SMTP Authorization. acl_verify_csa()
742 caches its result in a tree to avoid repeated DNS queries. The result is an
743 integer code which is used as an index into the following tables of
744 explanatory strings and verification return codes. */
746 static tree_node *csa_cache = NULL;
748 enum { CSA_UNKNOWN, CSA_OK, CSA_DEFER_SRV, CSA_DEFER_ADDR,
749 CSA_FAIL_EXPLICIT, CSA_FAIL_DOMAIN, CSA_FAIL_NOADDR, CSA_FAIL_MISMATCH };
751 /* The acl_verify_csa() return code is translated into an acl_verify() return
752 code using the following table. It is OK unless the client is definitely not
753 authorized. This is because CSA is supposed to be optional for sending sites,
754 so recipients should not be too strict about checking it - especially because
755 DNS problems are quite likely to occur. It's possible to use $csa_status in
756 further ACL conditions to distinguish ok, unknown, and defer if required, but
757 the aim is to make the usual configuration simple. */
759 static int csa_return_code[] = {
761 FAIL, FAIL, FAIL, FAIL
764 static uschar *csa_status_string[] = {
765 US"unknown", US"ok", US"defer", US"defer",
766 US"fail", US"fail", US"fail", US"fail"
769 static uschar *csa_reason_string[] = {
772 US"deferred (SRV lookup failed)",
773 US"deferred (target address lookup failed)",
774 US"failed (explicit authorization required)",
775 US"failed (host name not authorized)",
776 US"failed (no authorized addresses)",
777 US"failed (client address mismatch)"
780 /* Options for the ratelimit condition. Note that there are two variants of
781 the per_rcpt option, depending on the ACL that is used to measure the rate.
782 However any ACL must be able to look up per_rcpt rates in /noupdate mode,
783 so the two variants must have the same internal representation as well as
784 the same configuration string. */
787 RATE_PER_WHAT, RATE_PER_CLASH, RATE_PER_ADDR, RATE_PER_BYTE, RATE_PER_CMD,
788 RATE_PER_CONN, RATE_PER_MAIL, RATE_PER_RCPT, RATE_PER_ALLRCPTS
791 #define RATE_SET(var,new) \
792 (((var) == RATE_PER_WHAT) ? ((var) = RATE_##new) : ((var) = RATE_PER_CLASH))
794 static uschar *ratelimit_option_string[] = {
795 US"?", US"!", US"per_addr", US"per_byte", US"per_cmd",
796 US"per_conn", US"per_mail", US"per_rcpt", US"per_rcpt"
799 /* Enable recursion between acl_check_internal() and acl_check_condition() */
801 static int acl_check_wargs(int, address_item *, const uschar *, int, uschar **,
805 /*************************************************
806 * Pick out name from list *
807 *************************************************/
809 /* Use a binary chop method
816 Returns: offset in list, or -1 if not found
820 acl_checkname(uschar *name, uschar **list, int end)
826 int mid = (start + end)/2;
827 int c = Ustrcmp(name, list[mid]);
828 if (c == 0) return mid;
829 if (c < 0) end = mid; else start = mid + 1;
836 /*************************************************
837 * Read and parse one ACL *
838 *************************************************/
840 /* This function is called both from readconf in order to parse the ACLs in the
841 configuration file, and also when an ACL is encountered dynamically (e.g. as
842 the result of an expansion). It is given a function to call in order to
843 retrieve the lines of the ACL. This function handles skipping comments and
844 blank lines (where relevant).
847 func function to get next line of ACL
848 error where to put an error message
850 Returns: pointer to ACL, or NULL
851 NULL can be legal (empty ACL); in this case error will be NULL
855 acl_read(uschar *(*func)(void), uschar **error)
857 acl_block *yield = NULL;
858 acl_block **lastp = &yield;
859 acl_block *this = NULL;
860 acl_condition_block *cond;
861 acl_condition_block **condp = NULL;
866 while ((s = (*func)()) != NULL)
869 BOOL negated = FALSE;
870 uschar *saveline = s;
873 /* Conditions (but not verbs) are allowed to be negated by an initial
876 while (isspace(*s)) s++;
883 /* Read the name of a verb or a condition, or the start of a new ACL, which
884 can be started by a name, or by a macro definition. */
886 s = readconf_readname(name, sizeof(name), s);
887 if (*s == ':' || (isupper(name[0]) && *s == '=')) return yield;
889 /* If a verb is unrecognized, it may be another condition or modifier that
890 continues the previous verb. */
892 v = acl_checkname(name, verbs, sizeof(verbs)/sizeof(char *));
897 *error = string_sprintf("unknown ACL verb \"%s\" in \"%s\"", name,
909 *error = string_sprintf("malformed ACL line \"%s\"", saveline);
912 this = store_get(sizeof(acl_block));
914 lastp = &(this->next);
917 this->condition = NULL;
918 condp = &(this->condition);
919 if (*s == 0) continue; /* No condition on this line */
925 s = readconf_readname(name, sizeof(name), s); /* Condition name */
928 /* Handle a condition or modifier. */
930 c = acl_checkname(name, conditions, sizeof(conditions)/sizeof(char *));
933 *error = string_sprintf("unknown ACL condition/modifier in \"%s\"",
938 /* The modifiers may not be negated */
940 if (negated && cond_modifiers[c])
942 *error = string_sprintf("ACL error: negation is not allowed with "
943 "\"%s\"", conditions[c]);
947 /* ENDPASS may occur only with ACCEPT or DISCARD. */
949 if (c == ACLC_ENDPASS &&
950 this->verb != ACL_ACCEPT &&
951 this->verb != ACL_DISCARD)
953 *error = string_sprintf("ACL error: \"%s\" is not allowed with \"%s\"",
954 conditions[c], verbs[this->verb]);
958 cond = store_get(sizeof(acl_condition_block));
961 cond->u.negated = negated;
964 condp = &(cond->next);
966 /* The "set" modifier is different in that its argument is "name=value"
967 rather than just a value, and we can check the validity of the name, which
968 gives us a variable name to insert into the data block. The original ACL
969 variable names were acl_c0 ... acl_c9 and acl_m0 ... acl_m9. This was
970 extended to 20 of each type, but after that people successfully argued for
971 arbitrary names. In the new scheme, the names must start with acl_c or acl_m.
972 After that, we allow alphanumerics and underscores, but the first character
973 after c or m must be a digit or an underscore. This retains backwards
980 if (Ustrncmp(s, "acl_c", 5) != 0 &&
981 Ustrncmp(s, "acl_m", 5) != 0)
983 *error = string_sprintf("invalid variable name after \"set\" in ACL "
984 "modifier \"set %s\" (must start \"acl_c\" or \"acl_m\")", s);
989 if (!isdigit(*endptr) && *endptr != '_')
991 *error = string_sprintf("invalid variable name after \"set\" in ACL "
992 "modifier \"set %s\" (digit or underscore must follow acl_c or acl_m)",
997 while (*endptr != 0 && *endptr != '=' && !isspace(*endptr))
999 if (!isalnum(*endptr) && *endptr != '_')
1001 *error = string_sprintf("invalid character \"%c\" in variable name "
1002 "in ACL modifier \"set %s\"", *endptr, s);
1008 cond->u.varname = string_copyn(s + 4, endptr - s - 4);
1010 while (isspace(*s)) s++;
1013 /* For "set", we are now positioned for the data. For the others, only
1014 "endpass" has no data */
1016 if (c != ACLC_ENDPASS)
1020 *error = string_sprintf("\"=\" missing after ACL \"%s\" %s", name,
1021 cond_modifiers[c]? US"modifier" : US"condition");
1024 while (isspace(*s)) s++;
1025 cond->arg = string_copy(s);
1034 /*************************************************
1035 * Set up added header line(s) *
1036 *************************************************/
1038 /* This function is called by the add_header modifier, and also from acl_warn()
1039 to implement the now-deprecated way of adding header lines using "message" on a
1040 "warn" verb. The argument is treated as a sequence of header lines which are
1041 added to a chain, provided there isn't an identical one already there.
1043 Argument: string of header lines
1048 setup_header(const uschar *hstring)
1050 const uschar *p, *q;
1051 int hlen = Ustrlen(hstring);
1053 /* Ignore any leading newlines */
1054 while (*hstring == '\n') hstring++, hlen--;
1056 /* An empty string does nothing; ensure exactly one final newline. */
1057 if (hlen <= 0) return;
1058 if (hstring[--hlen] != '\n') /* no newline */
1059 q = string_sprintf("%s\n", hstring);
1060 else if (hstring[hlen-1] == '\n') /* double newline */
1062 uschar * s = string_copy(hstring);
1063 while(s[--hlen] == '\n')
1070 /* Loop for multiple header lines, taking care about continuations */
1072 for (p = q; *p != 0; )
1076 int newtype = htype_add_bot;
1077 header_line **hptr = &acl_added_headers;
1079 /* Find next header line within the string */
1083 q = Ustrchr(q, '\n'); /* we know there was a newline */
1084 if (*(++q) != ' ' && *q != '\t') break;
1087 /* If the line starts with a colon, interpret the instruction for where to
1088 add it. This temporarily sets up a new type. */
1092 if (strncmpic(p, US":after_received:", 16) == 0)
1094 newtype = htype_add_rec;
1097 else if (strncmpic(p, US":at_start_rfc:", 14) == 0)
1099 newtype = htype_add_rfc;
1102 else if (strncmpic(p, US":at_start:", 10) == 0)
1104 newtype = htype_add_top;
1107 else if (strncmpic(p, US":at_end:", 8) == 0)
1109 newtype = htype_add_bot;
1112 while (*p == ' ' || *p == '\t') p++;
1115 /* See if this line starts with a header name, and if not, add X-ACL-Warn:
1116 to the front of it. */
1118 for (s = p; s < q - 1; s++)
1120 if (*s == ':' || !isgraph(*s)) break;
1123 hdr = string_sprintf("%s%.*s", (*s == ':')? "" : "X-ACL-Warn: ", (int) (q - p), p);
1124 hlen = Ustrlen(hdr);
1126 /* See if this line has already been added */
1128 while (*hptr != NULL)
1130 if (Ustrncmp((*hptr)->text, hdr, hlen) == 0) break;
1131 hptr = &((*hptr)->next);
1134 /* Add if not previously present */
1138 header_line *h = store_get(sizeof(header_line));
1147 /* Advance for next header line within the string */
1155 /*************************************************
1156 * List the added header lines *
1157 *************************************************/
1161 uschar * ret = NULL;
1164 header_line * h = acl_added_headers;
1168 if (!h) return NULL;
1173 while ((cp = Ustrchr(s, '\n')) != NULL)
1175 if (cp[1] == '\0') break;
1177 /* contains embedded newline; needs doubling */
1178 ret = string_catn(ret, &size, &ptr, s, cp-s+1);
1179 ret = string_catn(ret, &size, &ptr, US"\n", 1);
1182 /* last bit of header */
1184 ret = string_catn(ret, &size, &ptr, s, cp-s+1); /* newline-sep list */
1186 while((h = h->next));
1188 ret[ptr-1] = '\0'; /* overwrite last newline */
1193 /*************************************************
1194 * Set up removed header line(s) *
1195 *************************************************/
1197 /* This function is called by the remove_header modifier. The argument is
1198 treated as a sequence of header names which are added to a colon separated
1199 list, provided there isn't an identical one already there.
1201 Argument: string of header names
1206 setup_remove_header(const uschar *hnames)
1209 acl_removed_headers = acl_removed_headers
1210 ? string_sprintf("%s : %s", acl_removed_headers, hnames)
1211 : string_copy(hnames);
1216 /*************************************************
1218 *************************************************/
1220 /* This function is called when a WARN verb's conditions are true. It adds to
1221 the message's headers, and/or writes information to the log. In each case, this
1222 only happens once (per message for headers, per connection for log).
1224 ** NOTE: The header adding action using the "message" setting is historic, and
1225 its use is now deprecated. The new add_header modifier should be used instead.
1228 where ACL_WHERE_xxxx indicating which ACL this is
1229 user_message message for adding to headers
1230 log_message message for logging, if different
1236 acl_warn(int where, uschar *user_message, uschar *log_message)
1238 if (log_message != NULL && log_message != user_message)
1241 string_item *logged;
1243 text = string_sprintf("%s Warning: %s", host_and_ident(TRUE),
1244 string_printing(log_message));
1246 /* If a sender verification has failed, and the log message is "sender verify
1247 failed", add the failure message. */
1249 if (sender_verified_failed != NULL &&
1250 sender_verified_failed->message != NULL &&
1251 strcmpic(log_message, US"sender verify failed") == 0)
1252 text = string_sprintf("%s: %s", text, sender_verified_failed->message);
1254 /* Search previously logged warnings. They are kept in malloc
1255 store so they can be freed at the start of a new message. */
1257 for (logged = acl_warn_logged; logged != NULL; logged = logged->next)
1258 if (Ustrcmp(logged->text, text) == 0) break;
1262 int length = Ustrlen(text) + 1;
1263 log_write(0, LOG_MAIN, "%s", text);
1264 logged = store_malloc(sizeof(string_item) + length);
1265 logged->text = (uschar *)logged + sizeof(string_item);
1266 memcpy(logged->text, text, length);
1267 logged->next = acl_warn_logged;
1268 acl_warn_logged = logged;
1272 /* If there's no user message, we are done. */
1274 if (user_message == NULL) return;
1276 /* If this isn't a message ACL, we can't do anything with a user message.
1279 if (where > ACL_WHERE_NOTSMTP)
1281 log_write(0, LOG_MAIN|LOG_PANIC, "ACL \"warn\" with \"message\" setting "
1282 "found in a non-message (%s) ACL: cannot specify header lines here: "
1283 "message ignored", acl_wherenames[where]);
1287 /* The code for setting up header lines is now abstracted into a separate
1288 function so that it can be used for the add_header modifier as well. */
1290 setup_header(user_message);
1295 /*************************************************
1296 * Verify and check reverse DNS *
1297 *************************************************/
1299 /* Called from acl_verify() below. We look up the host name(s) of the client IP
1300 address if this has not yet been done. The host_name_lookup() function checks
1301 that one of these names resolves to an address list that contains the client IP
1302 address, so we don't actually have to do the check here.
1305 user_msgptr pointer for user message
1306 log_msgptr pointer for log message
1308 Returns: OK verification condition succeeded
1309 FAIL verification failed
1310 DEFER there was a problem verifying
1314 acl_verify_reverse(uschar **user_msgptr, uschar **log_msgptr)
1318 user_msgptr = user_msgptr; /* stop compiler warning */
1320 /* Previous success */
1322 if (sender_host_name != NULL) return OK;
1324 /* Previous failure */
1326 if (host_lookup_failed)
1328 *log_msgptr = string_sprintf("host lookup failed%s", host_lookup_msg);
1332 /* Need to do a lookup */
1335 debug_printf("looking up host name to force name/address consistency check\n");
1337 if ((rc = host_name_lookup()) != OK)
1339 *log_msgptr = (rc == DEFER)?
1340 US"host lookup deferred for reverse lookup check"
1342 string_sprintf("host lookup failed for reverse lookup check%s",
1344 return rc; /* DEFER or FAIL */
1347 host_build_sender_fullhost();
1353 /*************************************************
1354 * Check client IP address matches CSA target *
1355 *************************************************/
1357 /* Called from acl_verify_csa() below. This routine scans a section of a DNS
1358 response for address records belonging to the CSA target hostname. The section
1359 is specified by the reset argument, either RESET_ADDITIONAL or RESET_ANSWERS.
1360 If one of the addresses matches the client's IP address, then the client is
1361 authorized by CSA. If there are target IP addresses but none of them match
1362 then the client is using an unauthorized IP address. If there are no target IP
1363 addresses then the client cannot be using an authorized IP address. (This is
1364 an odd configuration - why didn't the SRV record have a weight of 1 instead?)
1367 dnsa the DNS answer block
1368 dnss a DNS scan block for us to use
1369 reset option specifing what portion to scan, as described above
1370 target the target hostname to use for matching RR names
1372 Returns: CSA_OK successfully authorized
1373 CSA_FAIL_MISMATCH addresses found but none matched
1374 CSA_FAIL_NOADDR no target addresses found
1378 acl_verify_csa_address(dns_answer *dnsa, dns_scan *dnss, int reset,
1384 BOOL target_found = FALSE;
1386 for (rr = dns_next_rr(dnsa, dnss, reset);
1388 rr = dns_next_rr(dnsa, dnss, RESET_NEXT))
1390 /* Check this is an address RR for the target hostname. */
1394 && rr->type != T_AAAA
1398 if (strcmpic(target, rr->name) != 0) continue;
1400 target_found = TRUE;
1402 /* Turn the target address RR into a list of textual IP addresses and scan
1403 the list. There may be more than one if it is an A6 RR. */
1405 for (da = dns_address_from_rr(dnsa, rr); da != NULL; da = da->next)
1407 /* If the client IP address matches the target IP address, it's good! */
1409 DEBUG(D_acl) debug_printf("CSA target address is %s\n", da->address);
1411 if (strcmpic(sender_host_address, da->address) == 0) return CSA_OK;
1415 /* If we found some target addresses but none of them matched, the client is
1416 using an unauthorized IP address, otherwise the target has no authorized IP
1419 if (target_found) return CSA_FAIL_MISMATCH;
1420 else return CSA_FAIL_NOADDR;
1425 /*************************************************
1426 * Verify Client SMTP Authorization *
1427 *************************************************/
1429 /* Called from acl_verify() below. This routine calls dns_lookup_special()
1430 to find the CSA SRV record corresponding to the domain argument, or
1431 $sender_helo_name if no argument is provided. It then checks that the
1432 client is authorized, and that its IP address corresponds to the SRV
1433 target's address by calling acl_verify_csa_address() above. The address
1434 should have been returned in the DNS response's ADDITIONAL section, but if
1435 not we perform another DNS lookup to get it.
1438 domain pointer to optional parameter following verify = csa
1440 Returns: CSA_UNKNOWN no valid CSA record found
1441 CSA_OK successfully authorized
1442 CSA_FAIL_* client is definitely not authorized
1443 CSA_DEFER_* there was a DNS problem
1447 acl_verify_csa(const uschar *domain)
1450 const uschar *found;
1452 int priority, weight, port;
1459 /* Work out the domain we are using for the CSA lookup. The default is the
1460 client's HELO domain. If the client has not said HELO, use its IP address
1461 instead. If it's a local client (exim -bs), CSA isn't applicable. */
1463 while (isspace(*domain) && *domain != '\0') ++domain;
1464 if (*domain == '\0') domain = sender_helo_name;
1465 if (domain == NULL) domain = sender_host_address;
1466 if (sender_host_address == NULL) return CSA_UNKNOWN;
1468 /* If we have an address literal, strip off the framing ready for turning it
1469 into a domain. The framing consists of matched square brackets possibly
1470 containing a keyword and a colon before the actual IP address. */
1472 if (domain[0] == '[')
1474 const uschar *start = Ustrchr(domain, ':');
1475 if (start == NULL) start = domain;
1476 domain = string_copyn(start + 1, Ustrlen(start) - 2);
1479 /* Turn domains that look like bare IP addresses into domains in the reverse
1480 DNS. This code also deals with address literals and $sender_host_address. It's
1481 not quite kosher to treat bare domains such as EHLO 192.0.2.57 the same as
1482 address literals, but it's probably the most friendly thing to do. This is an
1483 extension to CSA, so we allow it to be turned off for proper conformance. */
1485 if (string_is_ip_address(domain, NULL) != 0)
1487 if (!dns_csa_use_reverse) return CSA_UNKNOWN;
1488 dns_build_reverse(domain, target);
1492 /* Find out if we've already done the CSA check for this domain. If we have,
1493 return the same result again. Otherwise build a new cached result structure
1494 for this domain. The name is filled in now, and the value is filled in when
1495 we return from this function. */
1497 t = tree_search(csa_cache, domain);
1498 if (t != NULL) return t->data.val;
1500 t = store_get_perm(sizeof(tree_node) + Ustrlen(domain));
1501 Ustrcpy(t->name, domain);
1502 (void)tree_insertnode(&csa_cache, t);
1504 /* Now we are ready to do the actual DNS lookup(s). */
1507 switch (dns_special_lookup(&dnsa, domain, T_CSA, &found))
1509 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1512 return t->data.val = CSA_DEFER_SRV;
1514 /* If we found nothing, the client's authorization is unknown. */
1518 return t->data.val = CSA_UNKNOWN;
1520 /* We got something! Go on to look at the reply in more detail. */
1526 /* Scan the reply for well-formed CSA SRV records. */
1528 for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS);
1530 rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT))
1532 if (rr->type != T_SRV) continue;
1534 /* Extract the numerical SRV fields (p is incremented) */
1537 GETSHORT(priority, p);
1538 GETSHORT(weight, p);
1542 debug_printf("CSA priority=%d weight=%d port=%d\n", priority, weight, port);
1544 /* Check the CSA version number */
1546 if (priority != 1) continue;
1548 /* If the domain does not have a CSA SRV record of its own (i.e. the domain
1549 found by dns_special_lookup() is a parent of the one we asked for), we check
1550 the subdomain assertions in the port field. At the moment there's only one
1551 assertion: legitimate SMTP clients are all explicitly authorized with CSA
1552 SRV records of their own. */
1554 if (Ustrcmp(found, domain) != 0)
1557 return t->data.val = CSA_FAIL_EXPLICIT;
1559 return t->data.val = CSA_UNKNOWN;
1562 /* This CSA SRV record refers directly to our domain, so we check the value
1563 in the weight field to work out the domain's authorization. 0 and 1 are
1564 unauthorized; 3 means the client is authorized but we can't check the IP
1565 address in order to authenticate it, so we treat it as unknown; values
1566 greater than 3 are undefined. */
1568 if (weight < 2) return t->data.val = CSA_FAIL_DOMAIN;
1570 if (weight > 2) continue;
1572 /* Weight == 2, which means the domain is authorized. We must check that the
1573 client's IP address is listed as one of the SRV target addresses. Save the
1574 target hostname then break to scan the additional data for its addresses. */
1576 (void)dn_expand(dnsa.answer, dnsa.answer + dnsa.answerlen, p,
1577 (DN_EXPAND_ARG4_TYPE)target, sizeof(target));
1579 DEBUG(D_acl) debug_printf("CSA target is %s\n", target);
1584 /* If we didn't break the loop then no appropriate records were found. */
1586 if (rr == NULL) return t->data.val = CSA_UNKNOWN;
1588 /* Do not check addresses if the target is ".", in accordance with RFC 2782.
1589 A target of "." indicates there are no valid addresses, so the client cannot
1590 be authorized. (This is an odd configuration because weight=2 target=. is
1591 equivalent to weight=1, but we check for it in order to keep load off the
1592 root name servers.) Note that dn_expand() turns "." into "". */
1594 if (Ustrcmp(target, "") == 0) return t->data.val = CSA_FAIL_NOADDR;
1596 /* Scan the additional section of the CSA SRV reply for addresses belonging
1597 to the target. If the name server didn't return any additional data (e.g.
1598 because it does not fully support SRV records), we need to do another lookup
1599 to obtain the target addresses; otherwise we have a definitive result. */
1601 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ADDITIONAL, target);
1602 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1604 /* The DNS lookup type corresponds to the IP version used by the client. */
1607 if (Ustrchr(sender_host_address, ':') != NULL)
1610 #endif /* HAVE_IPV6 */
1614 lookup_dnssec_authenticated = NULL;
1615 switch (dns_lookup(&dnsa, target, type, NULL))
1617 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1620 return t->data.val = CSA_DEFER_ADDR;
1622 /* If the query succeeded, scan the addresses and return the result. */
1625 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ANSWERS, target);
1626 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1627 /* else fall through */
1629 /* If the target has no IP addresses, the client cannot have an authorized
1630 IP address. However, if the target site uses A6 records (not AAAA records)
1631 we have to do yet another lookup in order to check them. */
1635 return t->data.val = CSA_FAIL_NOADDR;
1641 /*************************************************
1642 * Handle verification (address & other) *
1643 *************************************************/
1645 enum { VERIFY_REV_HOST_LKUP, VERIFY_CERT, VERIFY_HELO, VERIFY_CSA, VERIFY_HDR_SYNTAX,
1646 VERIFY_NOT_BLIND, VERIFY_HDR_SNDR, VERIFY_SNDR, VERIFY_RCPT,
1647 VERIFY_HDR_NAMES_ASCII
1652 unsigned where_allowed; /* bitmap */
1653 BOOL no_options; /* Never has /option(s) following */
1654 unsigned alt_opt_sep; /* >0 Non-/ option separator (custom parser) */
1656 static verify_type_t verify_type_list[] = {
1657 { US"reverse_host_lookup", VERIFY_REV_HOST_LKUP, ~0, FALSE, 0 },
1658 { US"certificate", VERIFY_CERT, ~0, TRUE, 0 },
1659 { US"helo", VERIFY_HELO, ~0, TRUE, 0 },
1660 { US"csa", VERIFY_CSA, ~0, FALSE, 0 },
1661 { US"header_syntax", VERIFY_HDR_SYNTAX, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), TRUE, 0 },
1662 { US"not_blind", VERIFY_NOT_BLIND, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), TRUE, 0 },
1663 { US"header_sender", VERIFY_HDR_SNDR, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), FALSE, 0 },
1664 { US"sender", VERIFY_SNDR, (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)
1665 |(1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP),
1667 { US"recipient", VERIFY_RCPT, (1<<ACL_WHERE_RCPT), FALSE, 0 },
1668 { US"header_names_ascii", VERIFY_HDR_NAMES_ASCII, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), TRUE, 0 }
1672 enum { CALLOUT_DEFER_OK, CALLOUT_NOCACHE, CALLOUT_RANDOM, CALLOUT_USE_SENDER,
1673 CALLOUT_USE_POSTMASTER, CALLOUT_POSTMASTER, CALLOUT_FULLPOSTMASTER,
1674 CALLOUT_MAILFROM, CALLOUT_POSTMASTER_MAILFROM, CALLOUT_MAXWAIT, CALLOUT_CONNECT,
1681 BOOL has_option; /* Has =option(s) following */
1682 BOOL timeval; /* Has a time value */
1684 static callout_opt_t callout_opt_list[] = {
1685 { US"defer_ok", CALLOUT_DEFER_OK, 0, FALSE, FALSE },
1686 { US"no_cache", CALLOUT_NOCACHE, vopt_callout_no_cache, FALSE, FALSE },
1687 { US"random", CALLOUT_RANDOM, vopt_callout_random, FALSE, FALSE },
1688 { US"use_sender", CALLOUT_USE_SENDER, vopt_callout_recipsender, FALSE, FALSE },
1689 { US"use_postmaster", CALLOUT_USE_POSTMASTER,vopt_callout_recippmaster, FALSE, FALSE },
1690 { US"postmaster_mailfrom",CALLOUT_POSTMASTER_MAILFROM,0, TRUE, FALSE },
1691 { US"postmaster", CALLOUT_POSTMASTER, 0, FALSE, FALSE },
1692 { US"fullpostmaster", CALLOUT_FULLPOSTMASTER,vopt_callout_fullpm, FALSE, FALSE },
1693 { US"mailfrom", CALLOUT_MAILFROM, 0, TRUE, FALSE },
1694 { US"maxwait", CALLOUT_MAXWAIT, 0, TRUE, TRUE },
1695 { US"connect", CALLOUT_CONNECT, 0, TRUE, TRUE },
1696 { NULL, CALLOUT_TIME, 0, FALSE, TRUE }
1701 /* This function implements the "verify" condition. It is called when
1702 encountered in any ACL, because some tests are almost always permitted. Some
1703 just don't make sense, and always fail (for example, an attempt to test a host
1704 lookup for a non-TCP/IP message). Others are restricted to certain ACLs.
1707 where where called from
1708 addr the recipient address that the ACL is handling, or NULL
1709 arg the argument of "verify"
1710 user_msgptr pointer for user message
1711 log_msgptr pointer for log message
1712 basic_errno where to put verify errno
1714 Returns: OK verification condition succeeded
1715 FAIL verification failed
1716 DEFER there was a problem verifying
1721 acl_verify(int where, address_item *addr, const uschar *arg,
1722 uschar **user_msgptr, uschar **log_msgptr, int *basic_errno)
1726 int callout_overall = -1;
1727 int callout_connect = -1;
1728 int verify_options = 0;
1730 BOOL verify_header_sender = FALSE;
1731 BOOL defer_ok = FALSE;
1732 BOOL callout_defer_ok = FALSE;
1733 BOOL no_details = FALSE;
1734 BOOL success_on_redirect = FALSE;
1735 address_item *sender_vaddr = NULL;
1736 uschar *verify_sender_address = NULL;
1737 uschar *pm_mailfrom = NULL;
1738 uschar *se_mailfrom = NULL;
1740 /* Some of the verify items have slash-separated options; some do not. Diagnose
1741 an error if options are given for items that don't expect them.
1744 uschar *slash = Ustrchr(arg, '/');
1745 const uschar *list = arg;
1746 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
1749 if (ss == NULL) goto BAD_VERIFY;
1751 /* Handle name/address consistency verification in a separate function. */
1753 for (vp= verify_type_list;
1754 (char *)vp < (char *)verify_type_list + sizeof(verify_type_list);
1757 if (vp->alt_opt_sep ? strncmpic(ss, vp->name, vp->alt_opt_sep) == 0
1758 : strcmpic (ss, vp->name) == 0)
1760 if ((char *)vp >= (char *)verify_type_list + sizeof(verify_type_list))
1763 if (vp->no_options && slash != NULL)
1765 *log_msgptr = string_sprintf("unexpected '/' found in \"%s\" "
1766 "(this verify item has no options)", arg);
1769 if (!(vp->where_allowed & (1<<where)))
1771 *log_msgptr = string_sprintf("cannot verify %s in ACL for %s", vp->name, acl_wherenames[where]);
1776 case VERIFY_REV_HOST_LKUP:
1777 if (sender_host_address == NULL) return OK;
1778 if ((rc = acl_verify_reverse(user_msgptr, log_msgptr)) == DEFER)
1779 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size)))
1780 if (strcmpic(ss, US"defer_ok") == 0)
1785 /* TLS certificate verification is done at STARTTLS time; here we just
1786 test whether it was successful or not. (This is for optional verification; for
1787 mandatory verification, the connection doesn't last this long.) */
1789 if (tls_in.certificate_verified) return OK;
1790 *user_msgptr = US"no verified certificate";
1794 /* We can test the result of optional HELO verification that might have
1795 occurred earlier. If not, we can attempt the verification now. */
1797 if (!helo_verified && !helo_verify_failed) smtp_verify_helo();
1798 return helo_verified? OK : FAIL;
1801 /* Do Client SMTP Authorization checks in a separate function, and turn the
1802 result code into user-friendly strings. */
1804 rc = acl_verify_csa(list);
1805 *log_msgptr = *user_msgptr = string_sprintf("client SMTP authorization %s",
1806 csa_reason_string[rc]);
1807 csa_status = csa_status_string[rc];
1808 DEBUG(D_acl) debug_printf("CSA result %s\n", csa_status);
1809 return csa_return_code[rc];
1811 case VERIFY_HDR_SYNTAX:
1812 /* Check that all relevant header lines have the correct syntax. If there is
1813 a syntax error, we return details of the error to the sender if configured to
1814 send out full details. (But a "message" setting on the ACL can override, as
1817 rc = verify_check_headers(log_msgptr);
1818 if (rc != OK && *log_msgptr)
1819 if (smtp_return_error_details)
1820 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1822 acl_verify_message = *log_msgptr;
1825 case VERIFY_HDR_NAMES_ASCII:
1826 /* Check that all header names are true 7 bit strings
1827 See RFC 5322, 2.2. and RFC 6532, 3. */
1829 rc = verify_check_header_names_ascii(log_msgptr);
1830 if (rc != OK && smtp_return_error_details && *log_msgptr != NULL)
1831 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1834 case VERIFY_NOT_BLIND:
1835 /* Check that no recipient of this message is "blind", that is, every envelope
1836 recipient must be mentioned in either To: or Cc:. */
1838 rc = verify_check_notblind();
1841 *log_msgptr = string_sprintf("bcc recipient detected");
1842 if (smtp_return_error_details)
1843 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1847 /* The remaining verification tests check recipient and sender addresses,
1848 either from the envelope or from the header. There are a number of
1849 slash-separated options that are common to all of them. */
1851 case VERIFY_HDR_SNDR:
1852 verify_header_sender = TRUE;
1856 /* In the case of a sender, this can optionally be followed by an address to use
1857 in place of the actual sender (rare special-case requirement). */
1861 verify_sender_address = sender_address;
1864 while (isspace(*s)) s++;
1865 if (*s++ != '=') goto BAD_VERIFY;
1866 while (isspace(*s)) s++;
1867 verify_sender_address = string_copy(s);
1878 /* Remaining items are optional; they apply to sender and recipient
1879 verification, including "header sender" verification. */
1881 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size))
1884 if (strcmpic(ss, US"defer_ok") == 0) defer_ok = TRUE;
1885 else if (strcmpic(ss, US"no_details") == 0) no_details = TRUE;
1886 else if (strcmpic(ss, US"success_on_redirect") == 0) success_on_redirect = TRUE;
1888 /* These two old options are left for backwards compatibility */
1890 else if (strcmpic(ss, US"callout_defer_ok") == 0)
1892 callout_defer_ok = TRUE;
1893 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1896 else if (strcmpic(ss, US"check_postmaster") == 0)
1899 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1902 /* The callout option has a number of sub-options, comma separated */
1904 else if (strncmpic(ss, US"callout", 7) == 0)
1906 callout = CALLOUT_TIMEOUT_DEFAULT;
1910 while (isspace(*ss)) ss++;
1913 const uschar * sublist = ss;
1917 while (isspace(*sublist)) sublist++;
1919 while ((opt = string_nextinlist(&sublist, &optsep, buffer, sizeof(buffer)))
1923 double period = 1.0F;
1925 for (op= callout_opt_list; op->name; op++)
1926 if (strncmpic(opt, op->name, Ustrlen(op->name)) == 0)
1929 verify_options |= op->flag;
1932 opt += Ustrlen(op->name);
1933 while (isspace(*opt)) opt++;
1936 *log_msgptr = string_sprintf("'=' expected after "
1937 "\"%s\" in ACL verify condition \"%s\"", op->name, arg);
1940 while (isspace(*opt)) opt++;
1944 period = readconf_readtime(opt, 0, FALSE);
1947 *log_msgptr = string_sprintf("bad time value in ACL condition "
1948 "\"verify %s\"", arg);
1955 case CALLOUT_DEFER_OK: callout_defer_ok = TRUE; break;
1956 case CALLOUT_POSTMASTER: pm_mailfrom = US""; break;
1957 case CALLOUT_FULLPOSTMASTER: pm_mailfrom = US""; break;
1958 case CALLOUT_MAILFROM:
1959 if (!verify_header_sender)
1961 *log_msgptr = string_sprintf("\"mailfrom\" is allowed as a "
1962 "callout option only for verify=header_sender (detected in ACL "
1963 "condition \"%s\")", arg);
1966 se_mailfrom = string_copy(opt);
1968 case CALLOUT_POSTMASTER_MAILFROM: pm_mailfrom = string_copy(opt); break;
1969 case CALLOUT_MAXWAIT: callout_overall = period; break;
1970 case CALLOUT_CONNECT: callout_connect = period; break;
1971 case CALLOUT_TIME: callout = period; break;
1977 *log_msgptr = string_sprintf("'=' expected after \"callout\" in "
1978 "ACL condition \"%s\"", arg);
1984 /* Option not recognized */
1988 *log_msgptr = string_sprintf("unknown option \"%s\" in ACL "
1989 "condition \"verify %s\"", ss, arg);
1994 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster)) ==
1995 (vopt_callout_recipsender|vopt_callout_recippmaster))
1997 *log_msgptr = US"only one of use_sender and use_postmaster can be set "
1998 "for a recipient callout";
2002 /* Handle sender-in-header verification. Default the user message to the log
2003 message if giving out verification details. */
2005 if (verify_header_sender)
2008 rc = verify_check_header_address(user_msgptr, log_msgptr, callout,
2009 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, verify_options,
2013 *basic_errno = verrno;
2014 if (smtp_return_error_details)
2016 if (*user_msgptr == NULL && *log_msgptr != NULL)
2017 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
2018 if (rc == DEFER) acl_temp_details = TRUE;
2023 /* Handle a sender address. The default is to verify *the* sender address, but
2024 optionally a different address can be given, for special requirements. If the
2025 address is empty, we are dealing with a bounce message that has no sender, so
2026 we cannot do any checking. If the real sender address gets rewritten during
2027 verification (e.g. DNS widening), set the flag to stop it being rewritten again
2028 during message reception.
2030 A list of verified "sender" addresses is kept to try to avoid doing to much
2031 work repetitively when there are multiple recipients in a message and they all
2032 require sender verification. However, when callouts are involved, it gets too
2033 complicated because different recipients may require different callout options.
2034 Therefore, we always do a full sender verify when any kind of callout is
2035 specified. Caching elsewhere, for instance in the DNS resolver and in the
2036 callout handling, should ensure that this is not terribly inefficient. */
2038 else if (verify_sender_address != NULL)
2040 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster))
2043 *log_msgptr = US"use_sender or use_postmaster cannot be used for a "
2044 "sender verify callout";
2048 sender_vaddr = verify_checked_sender(verify_sender_address);
2049 if (sender_vaddr != NULL && /* Previously checked */
2050 callout <= 0) /* No callout needed this time */
2052 /* If the "routed" flag is set, it means that routing worked before, so
2053 this check can give OK (the saved return code value, if set, belongs to a
2054 callout that was done previously). If the "routed" flag is not set, routing
2055 must have failed, so we use the saved return code. */
2057 if (testflag(sender_vaddr, af_verify_routed)) rc = OK; else
2059 rc = sender_vaddr->special_action;
2060 *basic_errno = sender_vaddr->basic_errno;
2062 HDEBUG(D_acl) debug_printf("using cached sender verify result\n");
2065 /* Do a new verification, and cache the result. The cache is used to avoid
2066 verifying the sender multiple times for multiple RCPTs when callouts are not
2067 specified (see comments above).
2069 The cache is also used on failure to give details in response to the first
2070 RCPT that gets bounced for this reason. However, this can be suppressed by
2071 the no_details option, which sets the flag that says "this detail has already
2072 been sent". The cache normally contains just one address, but there may be
2073 more in esoteric circumstances. */
2078 uschar *save_address_data = deliver_address_data;
2080 sender_vaddr = deliver_make_addr(verify_sender_address, TRUE);
2082 if ((sender_vaddr->prop.utf8_msg = message_smtputf8))
2084 sender_vaddr->prop.utf8_downcvt = message_utf8_downconvert == 1;
2085 sender_vaddr->prop.utf8_downcvt_maybe = message_utf8_downconvert == -1;
2088 if (no_details) setflag(sender_vaddr, af_sverify_told);
2089 if (verify_sender_address[0] != 0)
2091 /* If this is the real sender address, save the unrewritten version
2092 for use later in receive. Otherwise, set a flag so that rewriting the
2093 sender in verify_address() does not update sender_address. */
2095 if (verify_sender_address == sender_address)
2096 sender_address_unrewritten = sender_address;
2098 verify_options |= vopt_fake_sender;
2100 if (success_on_redirect)
2101 verify_options |= vopt_success_on_redirect;
2103 /* The recipient, qualify, and expn options are never set in
2106 rc = verify_address(sender_vaddr, NULL, verify_options, callout,
2107 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, &routed);
2109 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
2113 if (Ustrcmp(sender_vaddr->address, verify_sender_address) != 0)
2115 DEBUG(D_acl) debug_printf("sender %s verified ok as %s\n",
2116 verify_sender_address, sender_vaddr->address);
2120 DEBUG(D_acl) debug_printf("sender %s verified ok\n",
2121 verify_sender_address);
2124 else *basic_errno = sender_vaddr->basic_errno;
2126 else rc = OK; /* Null sender */
2128 /* Cache the result code */
2130 if (routed) setflag(sender_vaddr, af_verify_routed);
2131 if (callout > 0) setflag(sender_vaddr, af_verify_callout);
2132 sender_vaddr->special_action = rc;
2133 sender_vaddr->next = sender_verified_list;
2134 sender_verified_list = sender_vaddr;
2136 /* Restore the recipient address data, which might have been clobbered by
2137 the sender verification. */
2139 deliver_address_data = save_address_data;
2142 /* Put the sender address_data value into $sender_address_data */
2144 sender_address_data = sender_vaddr->prop.address_data;
2147 /* A recipient address just gets a straightforward verify; again we must handle
2148 the DEFER overrides. */
2154 if (success_on_redirect)
2155 verify_options |= vopt_success_on_redirect;
2157 /* We must use a copy of the address for verification, because it might
2161 rc = verify_address(&addr2, NULL, verify_options|vopt_is_recipient, callout,
2162 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, NULL);
2163 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
2165 *basic_errno = addr2.basic_errno;
2166 *log_msgptr = addr2.message;
2167 *user_msgptr = (addr2.user_message != NULL)?
2168 addr2.user_message : addr2.message;
2170 /* Allow details for temporary error if the address is so flagged. */
2171 if (testflag((&addr2), af_pass_message)) acl_temp_details = TRUE;
2173 /* Make $address_data visible */
2174 deliver_address_data = addr2.prop.address_data;
2177 /* We have a result from the relevant test. Handle defer overrides first. */
2179 if (rc == DEFER && (defer_ok ||
2180 (callout_defer_ok && *basic_errno == ERRNO_CALLOUTDEFER)))
2182 HDEBUG(D_acl) debug_printf("verify defer overridden by %s\n",
2183 defer_ok? "defer_ok" : "callout_defer_ok");
2187 /* If we've failed a sender, set up a recipient message, and point
2188 sender_verified_failed to the address item that actually failed. */
2190 if (rc != OK && verify_sender_address != NULL)
2193 *log_msgptr = *user_msgptr = US"Sender verify failed";
2194 else if (*basic_errno != ERRNO_CALLOUTDEFER)
2195 *log_msgptr = *user_msgptr = US"Could not complete sender verify";
2198 *log_msgptr = US"Could not complete sender verify callout";
2199 *user_msgptr = smtp_return_error_details? sender_vaddr->user_message :
2203 sender_verified_failed = sender_vaddr;
2206 /* Verifying an address messes up the values of $domain and $local_part,
2207 so reset them before returning if this is a RCPT ACL. */
2211 deliver_domain = addr->domain;
2212 deliver_localpart = addr->local_part;
2216 /* Syntax errors in the verify argument come here. */
2219 *log_msgptr = string_sprintf("expected \"sender[=address]\", \"recipient\", "
2220 "\"helo\", \"header_syntax\", \"header_sender\", \"header_names_ascii\" "
2221 "or \"reverse_host_lookup\" at start of ACL condition "
2222 "\"verify %s\"", arg);
2229 /*************************************************
2230 * Check argument for control= modifier *
2231 *************************************************/
2233 /* Called from acl_check_condition() below
2236 arg the argument string for control=
2237 pptr set to point to the terminating character
2238 where which ACL we are in
2239 log_msgptr for error messages
2241 Returns: CONTROL_xxx value
2245 decode_control(const uschar *arg, const uschar **pptr, int where, uschar **log_msgptr)
2250 for (d = controls_list;
2251 d < controls_list + sizeof(controls_list)/sizeof(control_def);
2254 len = Ustrlen(d->name);
2255 if (Ustrncmp(d->name, arg, len) == 0) break;
2258 if (d >= controls_list + sizeof(controls_list)/sizeof(control_def) ||
2259 (arg[len] != 0 && (!d->has_option || arg[len] != '/')))
2261 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
2262 return CONTROL_ERROR;
2272 /*************************************************
2273 * Return a ratelimit error *
2274 *************************************************/
2276 /* Called from acl_ratelimit() below
2279 log_msgptr for error messages
2280 format format string
2281 ... supplementary arguments
2282 ss ratelimit option name
2283 where ACL_WHERE_xxxx indicating which ACL this is
2289 ratelimit_error(uschar **log_msgptr, const char *format, ...)
2292 uschar buffer[STRING_SPRINTF_BUFFER_SIZE];
2293 va_start(ap, format);
2294 if (!string_vformat(buffer, sizeof(buffer), format, ap))
2295 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
2296 "string_sprintf expansion was longer than " SIZE_T_FMT, sizeof(buffer));
2298 *log_msgptr = string_sprintf(
2299 "error in arguments to \"ratelimit\" condition: %s", buffer);
2306 /*************************************************
2307 * Handle rate limiting *
2308 *************************************************/
2310 /* Called by acl_check_condition() below to calculate the result
2311 of the ACL ratelimit condition.
2313 Note that the return value might be slightly unexpected: if the
2314 sender's rate is above the limit then the result is OK. This is
2315 similar to the dnslists condition, and is so that you can write
2316 ACL clauses like: defer ratelimit = 15 / 1h
2319 arg the option string for ratelimit=
2320 where ACL_WHERE_xxxx indicating which ACL this is
2321 log_msgptr for error messages
2323 Returns: OK - Sender's rate is above limit
2324 FAIL - Sender's rate is below limit
2325 DEFER - Problem opening ratelimit database
2326 ERROR - Syntax error in options.
2330 acl_ratelimit(const uschar *arg, int where, uschar **log_msgptr)
2332 double limit, period, count;
2335 uschar *unique = NULL;
2337 BOOL leaky = FALSE, strict = FALSE, readonly = FALSE;
2338 BOOL noupdate = FALSE, badacl = FALSE;
2339 int mode = RATE_PER_WHAT;
2341 tree_node **anchor, *t;
2342 open_db dbblock, *dbm;
2344 dbdata_ratelimit *dbd;
2345 dbdata_ratelimit_unique *dbdb;
2348 /* Parse the first two options and record their values in expansion
2349 variables. These variables allow the configuration to have informative
2350 error messages based on rate limits obtained from a table lookup. */
2352 /* First is the maximum number of messages per period / maximum burst
2353 size, which must be greater than or equal to zero. Zero is useful for
2354 rate measurement as opposed to rate limiting. */
2356 sender_rate_limit = string_nextinlist(&arg, &sep, NULL, 0);
2357 if (sender_rate_limit == NULL)
2358 return ratelimit_error(log_msgptr, "sender rate limit not set");
2360 limit = Ustrtod(sender_rate_limit, &ss);
2361 if (tolower(*ss) == 'k') { limit *= 1024.0; ss++; }
2362 else if (tolower(*ss) == 'm') { limit *= 1024.0*1024.0; ss++; }
2363 else if (tolower(*ss) == 'g') { limit *= 1024.0*1024.0*1024.0; ss++; }
2365 if (limit < 0.0 || *ss != '\0')
2366 return ratelimit_error(log_msgptr,
2367 "\"%s\" is not a positive number", sender_rate_limit);
2369 /* Second is the rate measurement period / exponential smoothing time
2370 constant. This must be strictly greater than zero, because zero leads to
2371 run-time division errors. */
2373 sender_rate_period = string_nextinlist(&arg, &sep, NULL, 0);
2374 if (sender_rate_period == NULL) period = -1.0;
2375 else period = readconf_readtime(sender_rate_period, 0, FALSE);
2377 return ratelimit_error(log_msgptr,
2378 "\"%s\" is not a time value", sender_rate_period);
2380 /* By default we are counting one of something, but the per_rcpt,
2381 per_byte, and count options can change this. */
2385 /* Parse the other options. */
2387 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2390 if (strcmpic(ss, US"leaky") == 0) leaky = TRUE;
2391 else if (strcmpic(ss, US"strict") == 0) strict = TRUE;
2392 else if (strcmpic(ss, US"noupdate") == 0) noupdate = TRUE;
2393 else if (strcmpic(ss, US"readonly") == 0) readonly = TRUE;
2394 else if (strcmpic(ss, US"per_cmd") == 0) RATE_SET(mode, PER_CMD);
2395 else if (strcmpic(ss, US"per_conn") == 0)
2397 RATE_SET(mode, PER_CONN);
2398 if (where == ACL_WHERE_NOTSMTP || where == ACL_WHERE_NOTSMTP_START)
2401 else if (strcmpic(ss, US"per_mail") == 0)
2403 RATE_SET(mode, PER_MAIL);
2404 if (where > ACL_WHERE_NOTSMTP) badacl = TRUE;
2406 else if (strcmpic(ss, US"per_rcpt") == 0)
2408 /* If we are running in the RCPT ACL, then we'll count the recipients
2409 one by one, but if we are running when we have accumulated the whole
2410 list then we'll add them all in one batch. */
2411 if (where == ACL_WHERE_RCPT)
2412 RATE_SET(mode, PER_RCPT);
2413 else if (where >= ACL_WHERE_PREDATA && where <= ACL_WHERE_NOTSMTP)
2414 RATE_SET(mode, PER_ALLRCPTS), count = (double)recipients_count;
2415 else if (where == ACL_WHERE_MAIL || where > ACL_WHERE_NOTSMTP)
2416 RATE_SET(mode, PER_RCPT), badacl = TRUE;
2418 else if (strcmpic(ss, US"per_byte") == 0)
2420 /* If we have not yet received the message data and there was no SIZE
2421 declaration on the MAIL comand, then it's safe to just use a value of
2422 zero and let the recorded rate decay as if nothing happened. */
2423 RATE_SET(mode, PER_MAIL);
2424 if (where > ACL_WHERE_NOTSMTP) badacl = TRUE;
2425 else count = message_size < 0 ? 0.0 : (double)message_size;
2427 else if (strcmpic(ss, US"per_addr") == 0)
2429 RATE_SET(mode, PER_RCPT);
2430 if (where != ACL_WHERE_RCPT) badacl = TRUE, unique = US"*";
2431 else unique = string_sprintf("%s@%s", deliver_localpart, deliver_domain);
2433 else if (strncmpic(ss, US"count=", 6) == 0)
2436 count = Ustrtod(ss+6, &e);
2437 if (count < 0.0 || *e != '\0')
2438 return ratelimit_error(log_msgptr,
2439 "\"%s\" is not a positive number", ss);
2441 else if (strncmpic(ss, US"unique=", 7) == 0)
2442 unique = string_copy(ss + 7);
2443 else if (key == NULL)
2444 key = string_copy(ss);
2446 key = string_sprintf("%s/%s", key, ss);
2449 /* Sanity check. When the badacl flag is set the update mode must either
2450 be readonly (which is the default if it is omitted) or, for backwards
2451 compatibility, a combination of noupdate and strict or leaky. */
2453 if (mode == RATE_PER_CLASH)
2454 return ratelimit_error(log_msgptr, "conflicting per_* options");
2455 if (leaky + strict + readonly > 1)
2456 return ratelimit_error(log_msgptr, "conflicting update modes");
2457 if (badacl && (leaky || strict) && !noupdate)
2458 return ratelimit_error(log_msgptr,
2459 "\"%s\" must not have /leaky or /strict option in %s ACL",
2460 ratelimit_option_string[mode], acl_wherenames[where]);
2462 /* Set the default values of any unset options. In readonly mode we
2463 perform the rate computation without any increment so that its value
2464 decays to eventually allow over-limit senders through. */
2466 if (noupdate) readonly = TRUE, leaky = strict = FALSE;
2467 if (badacl) readonly = TRUE;
2468 if (readonly) count = 0.0;
2469 if (!strict && !readonly) leaky = TRUE;
2470 if (mode == RATE_PER_WHAT) mode = RATE_PER_MAIL;
2472 /* Create the lookup key. If there is no explicit key, use sender_host_address.
2473 If there is no sender_host_address (e.g. -bs or acl_not_smtp) then we simply
2474 omit it. The smoothing constant (sender_rate_period) and the per_xxx options
2475 are added to the key because they alter the meaning of the stored data. */
2478 key = (sender_host_address == NULL)? US"" : sender_host_address;
2480 key = string_sprintf("%s/%s/%s%s",
2482 ratelimit_option_string[mode],
2483 unique == NULL ? "" : "unique/",
2487 debug_printf("ratelimit condition count=%.0f %.1f/%s\n", count, limit, key);
2489 /* See if we have already computed the rate by looking in the relevant tree.
2490 For per-connection rate limiting, store tree nodes and dbdata in the permanent
2491 pool so that they survive across resets. In readonly mode we only remember the
2492 result for the rest of this command in case a later command changes it. After
2493 this bit of logic the code is independent of the per_* mode. */
2495 old_pool = store_pool;
2498 anchor = &ratelimiters_cmd;
2501 anchor = &ratelimiters_conn;
2502 store_pool = POOL_PERM;
2506 case RATE_PER_ALLRCPTS:
2507 anchor = &ratelimiters_mail;
2512 anchor = &ratelimiters_cmd;
2515 anchor = NULL; /* silence an "unused" complaint */
2516 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
2517 "internal ACL error: unknown ratelimit mode %d", mode);
2521 t = tree_search(*anchor, key);
2525 /* The following few lines duplicate some of the code below. */
2526 rc = (dbd->rate < limit)? FAIL : OK;
2527 store_pool = old_pool;
2528 sender_rate = string_sprintf("%.1f", dbd->rate);
2530 debug_printf("ratelimit found pre-computed rate %s\n", sender_rate);
2534 /* We aren't using a pre-computed rate, so get a previously recorded rate
2535 from the database, which will be updated and written back if required. */
2537 dbm = dbfn_open(US"ratelimit", O_RDWR, &dbblock, TRUE);
2540 store_pool = old_pool;
2542 HDEBUG(D_acl) debug_printf("ratelimit database not available\n");
2543 *log_msgptr = US"ratelimit database not available";
2546 dbdb = dbfn_read_with_length(dbm, key, &dbdb_size);
2549 gettimeofday(&tv, NULL);
2553 /* Locate the basic ratelimit block inside the DB data. */
2554 HDEBUG(D_acl) debug_printf("ratelimit found key in database\n");
2557 /* Forget the old Bloom filter if it is too old, so that we count each
2558 repeating event once per period. We don't simply clear and re-use the old
2559 filter because we want its size to change if the limit changes. Note that
2560 we keep the dbd pointer for copying the rate into the new data block. */
2562 if(unique != NULL && tv.tv_sec > dbdb->bloom_epoch + period)
2564 HDEBUG(D_acl) debug_printf("ratelimit discarding old Bloom filter\n");
2570 if(unique != NULL && dbdb_size < sizeof(*dbdb))
2572 HDEBUG(D_acl) debug_printf("ratelimit discarding undersize Bloom filter\n");
2577 /* Allocate a new data block if the database lookup failed
2578 or the Bloom filter passed its age limit. */
2584 /* No Bloom filter. This basic ratelimit block is initialized below. */
2585 HDEBUG(D_acl) debug_printf("ratelimit creating new rate data block\n");
2586 dbdb_size = sizeof(*dbd);
2587 dbdb = store_get(dbdb_size);
2592 HDEBUG(D_acl) debug_printf("ratelimit creating new Bloom filter\n");
2594 /* See the long comment below for an explanation of the magic number 2.
2595 The filter has a minimum size in case the rate limit is very small;
2596 this is determined by the definition of dbdata_ratelimit_unique. */
2598 extra = (int)limit * 2 - sizeof(dbdb->bloom);
2599 if (extra < 0) extra = 0;
2600 dbdb_size = sizeof(*dbdb) + extra;
2601 dbdb = store_get(dbdb_size);
2602 dbdb->bloom_epoch = tv.tv_sec;
2603 dbdb->bloom_size = sizeof(dbdb->bloom) + extra;
2604 memset(dbdb->bloom, 0, dbdb->bloom_size);
2606 /* Preserve any basic ratelimit data (which is our longer-term memory)
2607 by copying it from the discarded block. */
2617 /* If we are counting unique events, find out if this event is new or not.
2618 If the client repeats the event during the current period then it should be
2619 counted. We skip this code in readonly mode for efficiency, because any
2620 changes to the filter will be discarded and because count is already set to
2623 if (unique != NULL && !readonly)
2625 /* We identify unique events using a Bloom filter. (You can find my
2626 notes on Bloom filters at http://fanf.livejournal.com/81696.html)
2627 With the per_addr option, an "event" is a recipient address, though the
2628 user can use the unique option to define their own events. We only count
2629 an event if we have not seen it before.
2631 We size the filter according to the rate limit, which (in leaky mode)
2632 is the limit on the population of the filter. We allow 16 bits of space
2633 per entry (see the construction code above) and we set (up to) 8 of them
2634 when inserting an element (see the loop below). The probability of a false
2635 positive (an event we have not seen before but which we fail to count) is
2639 allzero = exp(-numhash * pop / size)
2640 = exp(-0.5 * pop / limit)
2641 fpr = pow(1 - allzero, numhash)
2643 For senders at the limit the fpr is 0.06% or 1 in 1700
2644 and for senders at half the limit it is 0.0006% or 1 in 170000
2646 In strict mode the Bloom filter can fill up beyond the normal limit, in
2647 which case the false positive rate will rise. This means that the
2648 measured rate for very fast senders can bogusly drop off after a while.
2650 At twice the limit, the fpr is 2.5% or 1 in 40
2651 At four times the limit, it is 31% or 1 in 3.2
2653 It takes ln(pop/limit) periods for an over-limit burst of pop events to
2654 decay below the limit, and if this is more than one then the Bloom filter
2655 will be discarded before the decay gets that far. The false positive rate
2656 at this threshold is 9.3% or 1 in 10.7. */
2659 unsigned n, hash, hinc;
2663 /* Instead of using eight independent hash values, we combine two values
2664 using the formula h1 + n * h2. This does not harm the Bloom filter's
2665 performance, and means the amount of hash we need is independent of the
2666 number of bits we set in the filter. */
2668 md5_start(&md5info);
2669 md5_end(&md5info, unique, Ustrlen(unique), md5sum);
2670 hash = md5sum[0] | md5sum[1] << 8 | md5sum[2] << 16 | md5sum[3] << 24;
2671 hinc = md5sum[4] | md5sum[5] << 8 | md5sum[6] << 16 | md5sum[7] << 24;
2673 /* Scan the bits corresponding to this event. A zero bit means we have
2674 not seen it before. Ensure all bits are set to record this event. */
2676 HDEBUG(D_acl) debug_printf("ratelimit checking uniqueness of %s\n", unique);
2679 for (n = 0; n < 8; n++, hash += hinc)
2681 int bit = 1 << (hash % 8);
2682 int byte = (hash / 8) % dbdb->bloom_size;
2683 if ((dbdb->bloom[byte] & bit) == 0)
2685 dbdb->bloom[byte] |= bit;
2690 /* If this event has occurred before, do not count it. */
2694 HDEBUG(D_acl) debug_printf("ratelimit event found in Bloom filter\n");
2698 HDEBUG(D_acl) debug_printf("ratelimit event added to Bloom filter\n");
2701 /* If there was no previous ratelimit data block for this key, initialize
2702 the new one, otherwise update the block from the database. The initial rate
2703 is what would be computed by the code below for an infinite interval. */
2707 HDEBUG(D_acl) debug_printf("ratelimit initializing new key's rate data\n");
2709 dbd->time_stamp = tv.tv_sec;
2710 dbd->time_usec = tv.tv_usec;
2715 /* The smoothed rate is computed using an exponentially weighted moving
2716 average adjusted for variable sampling intervals. The standard EWMA for
2717 a fixed sampling interval is: f'(t) = (1 - a) * f(t) + a * f'(t - 1)
2718 where f() is the measured value and f'() is the smoothed value.
2720 Old data decays out of the smoothed value exponentially, such that data n
2721 samples old is multiplied by a^n. The exponential decay time constant p
2722 is defined such that data p samples old is multiplied by 1/e, which means
2723 that a = exp(-1/p). We can maintain the same time constant for a variable
2724 sampling interval i by using a = exp(-i/p).
2726 The rate we are measuring is messages per period, suitable for directly
2727 comparing with the limit. The average rate between now and the previous
2728 message is period / interval, which we feed into the EWMA as the sample.
2730 It turns out that the number of messages required for the smoothed rate
2731 to reach the limit when they are sent in a burst is equal to the limit.
2732 This can be seen by analysing the value of the smoothed rate after N
2733 messages sent at even intervals. Let k = (1 - a) * p/i
2735 rate_1 = (1 - a) * p/i + a * rate_0
2737 rate_2 = k + a * rate_1
2738 = k + a * k + a^2 * rate_0
2739 rate_3 = k + a * k + a^2 * k + a^3 * rate_0
2740 rate_N = rate_0 * a^N + k * SUM(x=0..N-1)(a^x)
2741 = rate_0 * a^N + k * (1 - a^N) / (1 - a)
2742 = rate_0 * a^N + p/i * (1 - a^N)
2744 When N is large, a^N -> 0 so rate_N -> p/i as desired.
2746 rate_N = p/i + (rate_0 - p/i) * a^N
2747 a^N = (rate_N - p/i) / (rate_0 - p/i)
2748 N * -i/p = log((rate_N - p/i) / (rate_0 - p/i))
2749 N = p/i * log((rate_0 - p/i) / (rate_N - p/i))
2751 Numerical analysis of the above equation, setting the computed rate to
2752 increase from rate_0 = 0 to rate_N = limit, shows that for large sending
2753 rates, p/i, the number of messages N = limit. So limit serves as both the
2754 maximum rate measured in messages per period, and the maximum number of
2755 messages that can be sent in a fast burst. */
2757 double this_time = (double)tv.tv_sec
2758 + (double)tv.tv_usec / 1000000.0;
2759 double prev_time = (double)dbd->time_stamp
2760 + (double)dbd->time_usec / 1000000.0;
2762 /* We must avoid division by zero, and deal gracefully with the clock going
2763 backwards. If we blunder ahead when time is in reverse then the computed
2764 rate will be bogus. To be safe we clamp interval to a very small number. */
2766 double interval = this_time - prev_time <= 0.0 ? 1e-9
2767 : this_time - prev_time;
2769 double i_over_p = interval / period;
2770 double a = exp(-i_over_p);
2772 /* Combine the instantaneous rate (period / interval) with the previous rate
2773 using the smoothing factor a. In order to measure sized events, multiply the
2774 instantaneous rate by the count of bytes or recipients etc. */
2776 dbd->time_stamp = tv.tv_sec;
2777 dbd->time_usec = tv.tv_usec;
2778 dbd->rate = (1 - a) * count / i_over_p + a * dbd->rate;
2780 /* When events are very widely spaced the computed rate tends towards zero.
2781 Although this is accurate it turns out not to be useful for our purposes,
2782 especially when the first event after a long silence is the start of a spam
2783 run. A more useful model is that the rate for an isolated event should be the
2784 size of the event per the period size, ignoring the lack of events outside
2785 the current period and regardless of where the event falls in the period. So,
2786 if the interval was so long that the calculated rate is unhelpfully small, we
2787 re-intialize the rate. In the absence of higher-rate bursts, the condition
2788 below is true if the interval is greater than the period. */
2790 if (dbd->rate < count) dbd->rate = count;
2793 /* Clients sending at the limit are considered to be over the limit.
2794 This matters for edge cases such as a limit of zero, when the client
2795 should be completely blocked. */
2797 rc = (dbd->rate < limit)? FAIL : OK;
2799 /* Update the state if the rate is low or if we are being strict. If we
2800 are in leaky mode and the sender's rate is too high, we do not update
2801 the recorded rate in order to avoid an over-aggressive sender's retry
2802 rate preventing them from getting any email through. If readonly is set,
2803 neither leaky nor strict are set, so we do not do any updates. */
2805 if ((rc == FAIL && leaky) || strict)
2807 dbfn_write(dbm, key, dbdb, dbdb_size);
2808 HDEBUG(D_acl) debug_printf("ratelimit db updated\n");
2812 HDEBUG(D_acl) debug_printf("ratelimit db not updated: %s\n",
2813 readonly? "readonly mode" : "over the limit, but leaky");
2818 /* Store the result in the tree for future reference. */
2820 t = store_get(sizeof(tree_node) + Ustrlen(key));
2822 Ustrcpy(t->name, key);
2823 (void)tree_insertnode(anchor, t);
2825 /* We create the formatted version of the sender's rate very late in
2826 order to ensure that it is done using the correct storage pool. */
2828 store_pool = old_pool;
2829 sender_rate = string_sprintf("%.1f", dbd->rate);
2832 debug_printf("ratelimit computed rate %s\n", sender_rate);
2839 /*************************************************
2840 * The udpsend ACL modifier *
2841 *************************************************/
2843 /* Called by acl_check_condition() below.
2846 arg the option string for udpsend=
2847 log_msgptr for error messages
2849 Returns: OK - Completed.
2850 DEFER - Problem with DNS lookup.
2851 ERROR - Syntax error in options.
2855 acl_udpsend(const uschar *arg, uschar **log_msgptr)
2867 hostname = string_nextinlist(&arg, &sep, NULL, 0);
2868 portstr = string_nextinlist(&arg, &sep, NULL, 0);
2870 if (hostname == NULL)
2872 *log_msgptr = US"missing destination host in \"udpsend\" modifier";
2875 if (portstr == NULL)
2877 *log_msgptr = US"missing destination port in \"udpsend\" modifier";
2882 *log_msgptr = US"missing datagram payload in \"udpsend\" modifier";
2885 portnum = Ustrtol(portstr, &portend, 10);
2886 if (*portend != '\0')
2888 *log_msgptr = US"bad destination port in \"udpsend\" modifier";
2892 /* Make a single-item host list. */
2893 h = store_get(sizeof(host_item));
2894 memset(h, 0, sizeof(host_item));
2899 if (string_is_ip_address(hostname, NULL))
2900 h->address = hostname, r = HOST_FOUND;
2902 r = host_find_byname(h, NULL, 0, NULL, FALSE);
2903 if (r == HOST_FIND_FAILED || r == HOST_FIND_AGAIN)
2905 *log_msgptr = US"DNS lookup failed in \"udpsend\" modifier";
2910 debug_printf("udpsend [%s]:%d %s\n", h->address, portnum, arg);
2912 r = s = ip_connectedsocket(SOCK_DGRAM, h->address, portnum, portnum,
2914 if (r < 0) goto defer;
2916 r = send(s, arg, len, 0);
2919 errstr = US strerror(errno);
2927 string_sprintf("\"udpsend\" truncated from %d to %d octets", len, r);
2932 debug_printf("udpsend %d bytes\n", r);
2937 *log_msgptr = string_sprintf("\"udpsend\" failed: %s", errstr);
2943 /*************************************************
2944 * Handle conditions/modifiers on an ACL item *
2945 *************************************************/
2947 /* Called from acl_check() below.
2951 cb ACL condition block - if NULL, result is OK
2952 where where called from
2953 addr the address being checked for RCPT, or NULL
2954 level the nesting level
2955 epp pointer to pass back TRUE if "endpass" encountered
2956 (applies only to "accept" and "discard")
2957 user_msgptr user message pointer
2958 log_msgptr log message pointer
2959 basic_errno pointer to where to put verify error
2961 Returns: OK - all conditions are met
2962 DISCARD - an "acl" condition returned DISCARD - only allowed
2963 for "accept" or "discard" verbs
2964 FAIL - at least one condition fails
2965 FAIL_DROP - an "acl" condition returned FAIL_DROP
2966 DEFER - can't tell at the moment (typically, lookup defer,
2967 but can be temporary callout problem)
2968 ERROR - ERROR from nested ACL or expansion failure or other
2973 acl_check_condition(int verb, acl_condition_block *cb, int where,
2974 address_item *addr, int level, BOOL *epp, uschar **user_msgptr,
2975 uschar **log_msgptr, int *basic_errno)
2977 uschar *user_message = NULL;
2978 uschar *log_message = NULL;
2979 uschar *debug_tag = NULL;
2980 uschar *debug_opts = NULL;
2982 #ifdef WITH_CONTENT_SCAN
2986 for (; cb != NULL; cb = cb->next)
2991 /* The message and log_message items set up messages to be used in
2992 case of rejection. They are expanded later. */
2994 if (cb->type == ACLC_MESSAGE)
2996 HDEBUG(D_acl) debug_printf(" message: %s\n", cb->arg);
2997 user_message = cb->arg;
3001 if (cb->type == ACLC_LOG_MESSAGE)
3003 HDEBUG(D_acl) debug_printf("l_message: %s\n", cb->arg);
3004 log_message = cb->arg;
3008 /* The endpass "condition" just sets a flag to show it occurred. This is
3009 checked at compile time to be on an "accept" or "discard" item. */
3011 if (cb->type == ACLC_ENDPASS)
3017 /* For other conditions and modifiers, the argument is expanded now for some
3018 of them, but not for all, because expansion happens down in some lower level
3019 checking functions in some cases. */
3021 if (cond_expand_at_top[cb->type])
3023 arg = expand_string(cb->arg);
3026 if (expand_string_forcedfail) continue;
3027 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s",
3028 cb->arg, expand_string_message);
3029 return search_find_defer? DEFER : ERROR;
3034 /* Show condition, and expanded condition if it's different */
3039 debug_printf("check %s%s %n",
3040 (!cond_modifiers[cb->type] && cb->u.negated)? "!":"",
3041 conditions[cb->type], &lhswidth);
3043 if (cb->type == ACLC_SET)
3045 debug_printf("acl_%s ", cb->u.varname);
3046 lhswidth += 5 + Ustrlen(cb->u.varname);
3049 debug_printf("= %s\n", cb->arg);
3052 debug_printf("%.*s= %s\n", lhswidth,
3056 /* Check that this condition makes sense at this time */
3058 if ((cond_forbids[cb->type] & (1 << where)) != 0)
3060 *log_msgptr = string_sprintf("cannot %s %s condition in %s ACL",
3061 cond_modifiers[cb->type]? "use" : "test",
3062 conditions[cb->type], acl_wherenames[where]);
3066 /* Run the appropriate test for each condition, or take the appropriate
3067 action for the remaining modifiers. */
3071 case ACLC_ADD_HEADER:
3075 /* A nested ACL that returns "discard" makes sense only for an "accept" or
3079 rc = acl_check_wargs(where, addr, arg, level+1, user_msgptr, log_msgptr);
3080 if (rc == DISCARD && verb != ACL_ACCEPT && verb != ACL_DISCARD)
3082 *log_msgptr = string_sprintf("nested ACL returned \"discard\" for "
3083 "\"%s\" command (only allowed with \"accept\" or \"discard\")",
3089 case ACLC_AUTHENTICATED:
3090 rc = (sender_host_authenticated == NULL)? FAIL :
3091 match_isinlist(sender_host_authenticated, &arg, 0, NULL, NULL, MCL_STRING,
3095 #ifdef EXPERIMENTAL_BRIGHTMAIL
3096 case ACLC_BMI_OPTIN:
3098 int old_pool = store_pool;
3099 store_pool = POOL_PERM;
3100 bmi_current_optin = string_copy(arg);
3101 store_pool = old_pool;
3106 case ACLC_CONDITION:
3107 /* The true/false parsing here should be kept in sync with that used in
3108 expand.c when dealing with ECOND_BOOL so that we don't have too many
3109 different definitions of what can be a boolean. */
3111 ? Ustrspn(arg+1, "0123456789") == Ustrlen(arg+1) /* Negative number */
3112 : Ustrspn(arg, "0123456789") == Ustrlen(arg)) /* Digits, or empty */
3113 rc = (Uatoi(arg) == 0)? FAIL : OK;
3115 rc = (strcmpic(arg, US"no") == 0 ||
3116 strcmpic(arg, US"false") == 0)? FAIL :
3117 (strcmpic(arg, US"yes") == 0 ||
3118 strcmpic(arg, US"true") == 0)? OK : DEFER;
3120 *log_msgptr = string_sprintf("invalid \"condition\" value \"%s\"", arg);
3123 case ACLC_CONTINUE: /* Always succeeds */
3128 const uschar *p = NULL;
3129 control_type = decode_control(arg, &p, where, log_msgptr);
3131 /* Check if this control makes sense at this time */
3133 if ((control_forbids[control_type] & (1 << where)) != 0)
3135 *log_msgptr = string_sprintf("cannot use \"control=%s\" in %s ACL",
3136 controls[control_type], acl_wherenames[where]);
3140 switch(control_type)
3142 case CONTROL_AUTH_UNADVERTISED:
3143 allow_auth_unadvertised = TRUE;
3146 #ifdef EXPERIMENTAL_BRIGHTMAIL
3147 case CONTROL_BMI_RUN:
3152 #ifndef DISABLE_DKIM
3153 case CONTROL_DKIM_VERIFY:
3154 dkim_disable_verify = TRUE;
3155 #ifdef EXPERIMENTAL_DMARC
3156 /* Since DKIM was blocked, skip DMARC too */
3157 dmarc_disable_verify = TRUE;
3158 dmarc_enable_forensic = FALSE;
3163 #ifdef EXPERIMENTAL_DMARC
3164 case CONTROL_DMARC_VERIFY:
3165 dmarc_disable_verify = TRUE;
3168 case CONTROL_DMARC_FORENSIC:
3169 dmarc_enable_forensic = TRUE;
3176 int fd, af, level, optname, value;
3177 /* If we are acting on stdin, the setsockopt may fail if stdin is not
3178 a socket; we can accept that, we'll just debug-log failures anyway. */
3179 fd = fileno(smtp_in);
3180 af = ip_get_address_family(fd);
3184 debug_printf("smtp input is probably not a socket [%s], not setting DSCP\n",
3188 if (dscp_lookup(p+1, af, &level, &optname, &value))
3190 if (setsockopt(fd, level, optname, &value, sizeof(value)) < 0)
3192 HDEBUG(D_acl) debug_printf("failed to set input DSCP[%s]: %s\n",
3193 p+1, strerror(errno));
3197 HDEBUG(D_acl) debug_printf("set input DSCP to \"%s\"\n", p+1);
3202 *log_msgptr = string_sprintf("unrecognised DSCP value in \"control=%s\"", arg);
3208 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3216 case CONTROL_CASEFUL_LOCAL_PART:
3217 deliver_localpart = addr->cc_local_part;
3220 case CONTROL_CASELOWER_LOCAL_PART:
3221 deliver_localpart = addr->lc_local_part;
3224 case CONTROL_ENFORCE_SYNC:
3225 smtp_enforce_sync = TRUE;
3228 case CONTROL_NO_ENFORCE_SYNC:
3229 smtp_enforce_sync = FALSE;
3232 #ifdef WITH_CONTENT_SCAN
3233 case CONTROL_NO_MBOX_UNSPOOL:
3234 no_mbox_unspool = TRUE;
3238 case CONTROL_NO_MULTILINE:
3239 no_multiline_responses = TRUE;
3242 case CONTROL_NO_PIPELINING:
3243 pipelining_enable = FALSE;
3246 case CONTROL_NO_DELAY_FLUSH:
3247 disable_delay_flush = TRUE;
3250 case CONTROL_NO_CALLOUT_FLUSH:
3251 disable_callout_flush = TRUE;
3254 case CONTROL_FAKEREJECT:
3255 cancel_cutthrough_connection("fakereject");
3256 case CONTROL_FAKEDEFER:
3257 fake_response = (control_type == CONTROL_FAKEDEFER) ? DEFER : FAIL;
3260 const uschar *pp = p + 1;
3261 while (*pp != 0) pp++;
3262 fake_response_text = expand_string(string_copyn(p+1, pp-p-1));
3267 /* Explicitly reset to default string */
3268 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).";
3272 case CONTROL_FREEZE:
3273 deliver_freeze = TRUE;
3274 deliver_frozen_at = time(NULL);
3275 freeze_tell = freeze_tell_config; /* Reset to configured value */
3276 if (Ustrncmp(p, "/no_tell", 8) == 0)
3283 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3286 cancel_cutthrough_connection("item frozen");
3289 case CONTROL_QUEUE_ONLY:
3290 queue_only_policy = TRUE;
3291 cancel_cutthrough_connection("queueing forced");
3294 case CONTROL_SUBMISSION:
3295 originator_name = US"";
3296 submission_mode = TRUE;
3299 if (Ustrncmp(p, "/sender_retain", 14) == 0)
3302 active_local_sender_retain = TRUE;
3303 active_local_from_check = FALSE;
3305 else if (Ustrncmp(p, "/domain=", 8) == 0)
3307 const uschar *pp = p + 8;
3308 while (*pp != 0 && *pp != '/') pp++;
3309 submission_domain = string_copyn(p+8, pp-p-8);
3312 /* The name= option must be last, because it swallows the rest of
3314 else if (Ustrncmp(p, "/name=", 6) == 0)
3316 const uschar *pp = p + 6;
3317 while (*pp != 0) pp++;
3318 submission_name = string_copy(parse_fix_phrase(p+6, pp-p-6,
3319 big_buffer, big_buffer_size));
3326 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3334 if (Ustrncmp(p, "/tag=", 5) == 0)
3336 const uschar *pp = p + 5;
3337 while (*pp != '\0' && *pp != '/') pp++;
3338 debug_tag = string_copyn(p+5, pp-p-5);
3341 else if (Ustrncmp(p, "/opts=", 6) == 0)
3343 const uschar *pp = p + 6;
3344 while (*pp != '\0' && *pp != '/') pp++;
3345 debug_opts = string_copyn(p+6, pp-p-6);
3349 debug_logging_activate(debug_tag, debug_opts);
3352 case CONTROL_SUPPRESS_LOCAL_FIXUPS:
3353 suppress_local_fixups = TRUE;
3356 case CONTROL_CUTTHROUGH_DELIVERY:
3357 #ifndef DISABLE_PRDR
3362 /* Too hard to think about for now. We might in future cutthrough
3363 the case where both sides handle prdr and this-node prdr acl
3365 *log_msgptr = string_sprintf("PRDR on %s reception\n", arg);
3369 *log_msgptr = US"frozen";
3370 else if (queue_only_policy)
3371 *log_msgptr = US"queue-only";
3372 else if (fake_response == FAIL)
3373 *log_msgptr = US"fakereject";
3376 if (rcpt_count == 1) cutthrough.delivery = TRUE;
3379 *log_msgptr = string_sprintf("\"control=%s\" on %s item",
3385 case CONTROL_UTF8_DOWNCONVERT:
3390 message_utf8_downconvert = 1;
3391 addr->prop.utf8_downcvt = TRUE;
3392 addr->prop.utf8_downcvt_maybe = FALSE;
3398 message_utf8_downconvert = 0;
3399 addr->prop.utf8_downcvt = FALSE;
3400 addr->prop.utf8_downcvt_maybe = FALSE;
3404 if (p[1] == '-' && p[2] == '1')
3406 message_utf8_downconvert = -1;
3407 addr->prop.utf8_downcvt = FALSE;
3408 addr->prop.utf8_downcvt_maybe = TRUE;
3412 *log_msgptr = US"bad option value for control=utf8_downconvert";
3416 message_utf8_downconvert = 1;
3417 addr->prop.utf8_downcvt = TRUE;
3418 addr->prop.utf8_downcvt_maybe = FALSE;
3428 #ifdef EXPERIMENTAL_DCC
3431 /* Seperate the regular expression and any optional parameters. */
3432 const uschar * list = arg;
3433 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
3434 /* Run the dcc backend. */
3435 rc = dcc_process(&ss);
3436 /* Modify return code based upon the existance of options. */
3437 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size)))
3438 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
3439 rc = FAIL; /* FAIL so that the message is passed to the next ACL */
3444 #ifdef WITH_CONTENT_SCAN
3446 rc = mime_decode(&arg);
3452 int delay = readconf_readtime(arg, 0, FALSE);
3455 *log_msgptr = string_sprintf("syntax error in argument for \"delay\" "
3456 "modifier: \"%s\" is not a time value", arg);
3461 HDEBUG(D_acl) debug_printf("delay modifier requests %d-second delay\n",
3466 debug_printf("delay skipped in -bh checking mode\n");
3469 /* NOTE 1: Remember that we may be
3470 dealing with stdin/stdout here, in addition to TCP/IP connections.
3471 Also, delays may be specified for non-SMTP input, where smtp_out and
3472 smtp_in will be NULL. Whatever is done must work in all cases.
3474 NOTE 2: The added feature of flushing the output before a delay must
3475 apply only to SMTP input. Hence the test for smtp_out being non-NULL.
3480 if (smtp_out != NULL && !disable_delay_flush)
3483 #if !defined(NO_POLL_H) && defined (POLLRDHUP)
3489 p.fd = fileno(smtp_out);
3490 p.events = POLLRDHUP;
3493 if (poll(&p, n, delay*1000) > 0)
3494 HDEBUG(D_acl) debug_printf("delay cancelled by peer close\n");
3497 /* It appears to be impossible to detect that a TCP/IP connection has
3498 gone away without reading from it. This means that we cannot shorten
3499 the delay below if the client goes away, because we cannot discover
3500 that the client has closed its end of the connection. (The connection
3501 is actually in a half-closed state, waiting for the server to close its
3502 end.) It would be nice to be able to detect this state, so that the
3503 Exim process is not held up unnecessarily. However, it seems that we
3504 can't. The poll() function does not do the right thing, and in any case
3505 it is not always available.
3508 while (delay > 0) delay = sleep(delay);
3515 #ifndef DISABLE_DKIM
3516 case ACLC_DKIM_SIGNER:
3517 if (dkim_cur_signer != NULL)
3518 rc = match_isinlist(dkim_cur_signer,
3519 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
3524 case ACLC_DKIM_STATUS:
3525 rc = match_isinlist(dkim_exim_expand_query(DKIM_VERIFY_STATUS),
3526 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
3530 #ifdef EXPERIMENTAL_DMARC
3531 case ACLC_DMARC_STATUS:
3532 if (!dmarc_has_been_checked)
3534 dmarc_has_been_checked = TRUE;
3535 /* used long way of dmarc_exim_expand_query() in case we need more
3536 * view into the process in the future. */
3537 rc = match_isinlist(dmarc_exim_expand_query(DMARC_VERIFY_STATUS),
3538 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
3543 rc = verify_check_dnsbl(where, &arg, log_msgptr);
3547 rc = match_isinlist(addr->domain, &arg, 0, &domainlist_anchor,
3548 addr->domain_cache, MCL_DOMAIN, TRUE, CUSS &deliver_domain_data);
3551 /* The value in tls_cipher is the full cipher name, for example,
3552 TLSv1:DES-CBC3-SHA:168, whereas the values to test for are just the
3553 cipher names such as DES-CBC3-SHA. But program defensively. We don't know
3554 what may in practice come out of the SSL library - which at the time of
3555 writing is poorly documented. */
3557 case ACLC_ENCRYPTED:
3558 if (tls_in.cipher == NULL) rc = FAIL; else
3560 uschar *endcipher = NULL;
3561 uschar *cipher = Ustrchr(tls_in.cipher, ':');
3562 if (cipher == NULL) cipher = tls_in.cipher; else
3564 endcipher = Ustrchr(++cipher, ':');
3565 if (endcipher != NULL) *endcipher = 0;
3567 rc = match_isinlist(cipher, &arg, 0, NULL, NULL, MCL_STRING, TRUE, NULL);
3568 if (endcipher != NULL) *endcipher = ':';
3572 /* Use verify_check_this_host() instead of verify_check_host() so that
3573 we can pass over &host_data to catch any looked up data. Once it has been
3574 set, it retains its value so that it's still there if another ACL verb
3575 comes through here and uses the cache. However, we must put it into
3576 permanent store in case it is also expected to be used in a subsequent
3577 message in the same SMTP connection. */
3580 rc = verify_check_this_host(&arg, sender_host_cache, NULL,
3581 (sender_host_address == NULL)? US"" : sender_host_address,
3583 if (rc == DEFER) *log_msgptr = search_error_message;
3584 if (host_data) host_data = string_copy_malloc(host_data);
3587 case ACLC_LOCAL_PARTS:
3588 rc = match_isinlist(addr->cc_local_part, &arg, 0,
3589 &localpartlist_anchor, addr->localpart_cache, MCL_LOCALPART, TRUE,
3590 CUSS &deliver_localpart_data);
3593 case ACLC_LOG_REJECT_TARGET:
3597 const uschar *s = arg;
3599 while ((ss = string_nextinlist(&s, &sep, big_buffer, big_buffer_size)))
3601 if (Ustrcmp(ss, "main") == 0) logbits |= LOG_MAIN;
3602 else if (Ustrcmp(ss, "panic") == 0) logbits |= LOG_PANIC;
3603 else if (Ustrcmp(ss, "reject") == 0) logbits |= LOG_REJECT;
3606 logbits |= LOG_MAIN|LOG_REJECT;
3607 log_write(0, LOG_MAIN|LOG_PANIC, "unknown log name \"%s\" in "
3608 "\"log_reject_target\" in %s ACL", ss, acl_wherenames[where]);
3611 log_reject_target = logbits;
3618 const uschar *s = arg;
3624 if (Ustrncmp(s, "main", 4) == 0)
3625 { logbits |= LOG_MAIN; s += 4; }
3626 else if (Ustrncmp(s, "panic", 5) == 0)
3627 { logbits |= LOG_PANIC; s += 5; }
3628 else if (Ustrncmp(s, "reject", 6) == 0)
3629 { logbits |= LOG_REJECT; s += 6; }
3632 logbits = LOG_MAIN|LOG_PANIC;
3633 s = string_sprintf(":unknown log name in \"%s\" in "
3634 "\"logwrite\" in %s ACL", arg, acl_wherenames[where]);
3640 while (isspace(*s)) s++;
3643 if (logbits == 0) logbits = LOG_MAIN;
3644 log_write(0, logbits, "%s", string_printing(s));
3648 #ifdef WITH_CONTENT_SCAN
3649 case ACLC_MALWARE: /* Run the malware backend. */
3651 /* Separate the regular expression and any optional parameters. */
3652 const uschar * list = arg;
3653 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
3655 BOOL defer_ok = FALSE;
3658 while ((opt = string_nextinlist(&list, &sep, NULL, 0)))
3659 if (strcmpic(opt, US"defer_ok") == 0)
3661 else if ( strncmpic(opt, US"tmo=", 4) == 0
3662 && (timeout = readconf_readtime(opt+4, '\0', FALSE)) < 0
3665 *log_msgptr = string_sprintf("bad timeout value in '%s'", opt);
3669 rc = malware(ss, timeout);
3670 if (rc == DEFER && defer_ok)
3671 rc = FAIL; /* FAIL so that the message is passed to the next ACL */
3675 case ACLC_MIME_REGEX:
3676 rc = mime_regex(&arg);
3680 case ACLC_RATELIMIT:
3681 rc = acl_ratelimit(arg, where, log_msgptr);
3684 case ACLC_RECIPIENTS:
3685 rc = match_address_list((const uschar *)addr->address, TRUE, TRUE, &arg, NULL, -1, 0,
3686 CUSS &recipient_data);
3689 #ifdef WITH_CONTENT_SCAN
3695 case ACLC_REMOVE_HEADER:
3696 setup_remove_header(arg);
3699 case ACLC_SENDER_DOMAINS:
3702 sdomain = Ustrrchr(sender_address, '@');
3703 sdomain = (sdomain == NULL)? US"" : sdomain + 1;
3704 rc = match_isinlist(sdomain, &arg, 0, &domainlist_anchor,
3705 sender_domain_cache, MCL_DOMAIN, TRUE, NULL);
3710 rc = match_address_list((const uschar *)sender_address, TRUE, TRUE, &arg,
3711 sender_address_cache, -1, 0, CUSS &sender_data);
3714 /* Connection variables must persist forever */
3718 int old_pool = store_pool;
3719 if ( cb->u.varname[0] == 'c'
3720 #ifndef DISABLE_EVENT
3721 || event_name /* An event is being delivered */
3724 store_pool = POOL_PERM;
3725 acl_var_create(cb->u.varname)->data.ptr = string_copy(arg);
3726 store_pool = old_pool;
3730 #ifdef WITH_CONTENT_SCAN
3733 /* Seperate the regular expression and any optional parameters. */
3734 const uschar * list = arg;
3735 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
3736 /* Run the spam backend. */
3737 rc = spam(CUSS &ss);
3738 /* Modify return code based upon the existance of options. */
3739 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size))
3741 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
3743 /* FAIL so that the message is passed to the next ACL */
3751 #ifdef EXPERIMENTAL_SPF
3753 rc = spf_process(&arg, sender_address, SPF_PROCESS_NORMAL);
3755 case ACLC_SPF_GUESS:
3756 rc = spf_process(&arg, sender_address, SPF_PROCESS_GUESS);
3761 rc = acl_udpsend(arg, log_msgptr);
3764 /* If the verb is WARN, discard any user message from verification, because
3765 such messages are SMTP responses, not header additions. The latter come
3766 only from explicit "message" modifiers. However, put the user message into
3767 $acl_verify_message so it can be used in subsequent conditions or modifiers
3768 (until something changes it). */
3771 rc = acl_verify(where, addr, arg, user_msgptr, log_msgptr, basic_errno);
3773 acl_verify_message = *user_msgptr;
3774 if (verb == ACL_WARN) *user_msgptr = NULL;
3778 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown "
3779 "condition %d", cb->type);
3783 /* If a condition was negated, invert OK/FAIL. */
3785 if (!cond_modifiers[cb->type] && cb->u.negated)
3787 if (rc == OK) rc = FAIL;
3788 else if (rc == FAIL || rc == FAIL_DROP) rc = OK;
3791 if (rc != OK) break; /* Conditions loop */
3795 /* If the result is the one for which "message" and/or "log_message" are used,
3796 handle the values of these modifiers. If there isn't a log message set, we make
3797 it the same as the user message.
3799 "message" is a user message that will be included in an SMTP response. Unless
3800 it is empty, it overrides any previously set user message.
3802 "log_message" is a non-user message, and it adds to any existing non-user
3803 message that is already set.
3805 Most verbs have but a single return for which the messages are relevant, but
3806 for "discard", it's useful to have the log message both when it succeeds and
3807 when it fails. For "accept", the message is used in the OK case if there is no
3808 "endpass", but (for backwards compatibility) in the FAIL case if "endpass" is
3811 if (*epp && rc == OK) user_message = NULL;
3813 if (((1<<rc) & msgcond[verb]) != 0)
3816 uschar *old_user_msgptr = *user_msgptr;
3817 uschar *old_log_msgptr = (*log_msgptr != NULL)? *log_msgptr : old_user_msgptr;
3819 /* If the verb is "warn", messages generated by conditions (verification or
3820 nested ACLs) are always discarded. This also happens for acceptance verbs
3821 when they actually do accept. Only messages specified at this level are used.
3822 However, the value of an existing message is available in $acl_verify_message
3823 during expansions. */
3825 if (verb == ACL_WARN ||
3826 (rc == OK && (verb == ACL_ACCEPT || verb == ACL_DISCARD)))
3827 *log_msgptr = *user_msgptr = NULL;
3829 if (user_message != NULL)
3831 acl_verify_message = old_user_msgptr;
3832 expmessage = expand_string(user_message);
3833 if (expmessage == NULL)
3835 if (!expand_string_forcedfail)
3836 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
3837 user_message, expand_string_message);
3839 else if (expmessage[0] != 0) *user_msgptr = expmessage;
3842 if (log_message != NULL)
3844 acl_verify_message = old_log_msgptr;
3845 expmessage = expand_string(log_message);
3846 if (expmessage == NULL)
3848 if (!expand_string_forcedfail)
3849 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
3850 log_message, expand_string_message);
3852 else if (expmessage[0] != 0)
3854 *log_msgptr = (*log_msgptr == NULL)? expmessage :
3855 string_sprintf("%s: %s", expmessage, *log_msgptr);
3859 /* If no log message, default it to the user message */
3861 if (*log_msgptr == NULL) *log_msgptr = *user_msgptr;
3864 acl_verify_message = NULL;
3872 /*************************************************
3873 * Get line from a literal ACL *
3874 *************************************************/
3876 /* This function is passed to acl_read() in order to extract individual lines
3877 of a literal ACL, which we access via static pointers. We can destroy the
3878 contents because this is called only once (the compiled ACL is remembered).
3880 This code is intended to treat the data in the same way as lines in the main
3881 Exim configuration file. That is:
3883 . Leading spaces are ignored.
3885 . A \ at the end of a line is a continuation - trailing spaces after the \
3886 are permitted (this is because I don't believe in making invisible things
3887 significant). Leading spaces on the continued part of a line are ignored.
3889 . Physical lines starting (significantly) with # are totally ignored, and
3890 may appear within a sequence of backslash-continued lines.
3892 . Blank lines are ignored, but will end a sequence of continuations.
3895 Returns: a pointer to the next line
3899 static uschar *acl_text; /* Current pointer in the text */
3900 static uschar *acl_text_end; /* Points one past the terminating '0' */
3908 /* This loop handles leading blank lines and comments. */
3912 while (isspace(*acl_text)) acl_text++; /* Leading spaces/empty lines */
3913 if (*acl_text == 0) return NULL; /* No more data */
3914 yield = acl_text; /* Potential data line */
3916 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3918 /* If we hit the end before a newline, we have the whole logical line. If
3919 it's a comment, there's no more data to be given. Otherwise, yield it. */
3921 if (*acl_text == 0) return (*yield == '#')? NULL : yield;
3923 /* After reaching a newline, end this loop if the physical line does not
3924 start with '#'. If it does, it's a comment, and the loop continues. */
3926 if (*yield != '#') break;
3929 /* This loop handles continuations. We know we have some real data, ending in
3930 newline. See if there is a continuation marker at the end (ignoring trailing
3931 white space). We know that *yield is not white space, so no need to test for
3932 cont > yield in the backwards scanning loop. */
3937 for (cont = acl_text - 1; isspace(*cont); cont--);
3939 /* If no continuation follows, we are done. Mark the end of the line and
3948 /* We have encountered a continuation. Skip over whitespace at the start of
3949 the next line, and indeed the whole of the next line or lines if they are
3954 while (*(++acl_text) == ' ' || *acl_text == '\t');
3955 if (*acl_text != '#') break;
3956 while (*(++acl_text) != 0 && *acl_text != '\n');
3959 /* We have the start of a continuation line. Move all the rest of the data
3960 to join onto the previous line, and then find its end. If the end is not a
3961 newline, we are done. Otherwise loop to look for another continuation. */
3963 memmove(cont, acl_text, acl_text_end - acl_text);
3964 acl_text_end -= acl_text - cont;
3966 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3967 if (*acl_text == 0) return yield;
3970 /* Control does not reach here */
3977 /*************************************************
3978 * Check access using an ACL *
3979 *************************************************/
3981 /* This function is called from address_check. It may recurse via
3982 acl_check_condition() - hence the use of a level to stop looping. The ACL is
3983 passed as a string which is expanded. A forced failure implies no access check
3984 is required. If the result is a single word, it is taken as the name of an ACL
3985 which is sought in the global ACL tree. Otherwise, it is taken as literal ACL
3986 text, complete with newlines, and parsed as such. In both cases, the ACL check
3987 is then run. This function uses an auxiliary function for acl_read() to call
3988 for reading individual lines of a literal ACL. This is acl_getline(), which
3989 appears immediately above.
3992 where where called from
3993 addr address item when called from RCPT; otherwise NULL
3994 s the input string; NULL is the same as an empty ACL => DENY
3995 level the nesting level
3996 user_msgptr where to put a user error (for SMTP response)
3997 log_msgptr where to put a logging message (not for SMTP response)
3999 Returns: OK access is granted
4000 DISCARD access is apparently granted...
4001 FAIL access is denied
4002 FAIL_DROP access is denied; drop the connection
4003 DEFER can't tell at the moment
4008 acl_check_internal(int where, address_item *addr, uschar *s, int level,
4009 uschar **user_msgptr, uschar **log_msgptr)
4012 acl_block *acl = NULL;
4013 uschar *acl_name = US"inline ACL";
4016 /* Catch configuration loops */
4020 *log_msgptr = US"ACL nested too deep: possible loop";
4026 HDEBUG(D_acl) debug_printf("ACL is NULL: implicit DENY\n");
4030 /* At top level, we expand the incoming string. At lower levels, it has already
4031 been expanded as part of condition processing. */
4035 ss = expand_string(s);
4038 if (expand_string_forcedfail) return OK;
4039 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s", s,
4040 expand_string_message);
4046 while (isspace(*ss))ss++;
4048 /* If we can't find a named ACL, the default is to parse it as an inline one.
4049 (Unless it begins with a slash; non-existent files give rise to an error.) */
4053 /* Handle the case of a string that does not contain any spaces. Look for a
4054 named ACL among those read from the configuration, or a previously read file.
4055 It is possible that the pointer to the ACL is NULL if the configuration
4056 contains a name with no data. If not found, and the text begins with '/',
4057 read an ACL from a file, and save it so it can be re-used. */
4059 if (Ustrchr(ss, ' ') == NULL)
4061 tree_node *t = tree_search(acl_anchor, ss);
4064 acl = (acl_block *)(t->data.ptr);
4067 HDEBUG(D_acl) debug_printf("ACL \"%s\" is empty: implicit DENY\n", ss);
4070 acl_name = string_sprintf("ACL \"%s\"", ss);
4071 HDEBUG(D_acl) debug_printf("using ACL \"%s\"\n", ss);
4074 else if (*ss == '/')
4076 struct stat statbuf;
4077 fd = Uopen(ss, O_RDONLY, 0);
4080 *log_msgptr = string_sprintf("failed to open ACL file \"%s\": %s", ss,
4085 if (fstat(fd, &statbuf) != 0)
4087 *log_msgptr = string_sprintf("failed to fstat ACL file \"%s\": %s", ss,
4092 acl_text = store_get(statbuf.st_size + 1);
4093 acl_text_end = acl_text + statbuf.st_size + 1;
4095 if (read(fd, acl_text, statbuf.st_size) != statbuf.st_size)
4097 *log_msgptr = string_sprintf("failed to read ACL file \"%s\": %s",
4098 ss, strerror(errno));
4101 acl_text[statbuf.st_size] = 0;
4104 acl_name = string_sprintf("ACL \"%s\"", ss);
4105 HDEBUG(D_acl) debug_printf("read ACL from file %s\n", ss);
4109 /* Parse an ACL that is still in text form. If it came from a file, remember it
4110 in the ACL tree, having read it into the POOL_PERM store pool so that it
4111 persists between multiple messages. */
4115 int old_pool = store_pool;
4116 if (fd >= 0) store_pool = POOL_PERM;
4117 acl = acl_read(acl_getline, log_msgptr);
4118 store_pool = old_pool;
4119 if (acl == NULL && *log_msgptr != NULL) return ERROR;
4122 tree_node *t = store_get_perm(sizeof(tree_node) + Ustrlen(ss));
4123 Ustrcpy(t->name, ss);
4125 (void)tree_insertnode(&acl_anchor, t);
4129 /* Now we have an ACL to use. It's possible it may be NULL. */
4134 int basic_errno = 0;
4135 BOOL endpass_seen = FALSE;
4136 BOOL acl_quit_check = level == 0
4137 && (where == ACL_WHERE_QUIT || where == ACL_WHERE_NOTQUIT);
4139 *log_msgptr = *user_msgptr = NULL;
4140 acl_temp_details = FALSE;
4142 HDEBUG(D_acl) debug_printf("processing \"%s\"\n", verbs[acl->verb]);
4144 /* Clear out any search error message from a previous check before testing
4147 search_error_message = NULL;
4148 cond = acl_check_condition(acl->verb, acl->condition, where, addr, level,
4149 &endpass_seen, user_msgptr, log_msgptr, &basic_errno);
4151 /* Handle special returns: DEFER causes a return except on a WARN verb;
4152 ERROR always causes a return. */
4157 HDEBUG(D_acl) debug_printf("%s: condition test deferred in %s\n", verbs[acl->verb], acl_name);
4158 if (basic_errno != ERRNO_CALLOUTDEFER)
4160 if (search_error_message != NULL && *search_error_message != 0)
4161 *log_msgptr = search_error_message;
4162 if (smtp_return_error_details) acl_temp_details = TRUE;
4166 acl_temp_details = TRUE;
4168 if (acl->verb != ACL_WARN) return DEFER;
4171 default: /* Paranoia */
4173 HDEBUG(D_acl) debug_printf("%s: condition test error in %s\n", verbs[acl->verb], acl_name);
4177 HDEBUG(D_acl) debug_printf("%s: condition test succeeded in %s\n",
4178 verbs[acl->verb], acl_name);
4182 HDEBUG(D_acl) debug_printf("%s: condition test failed in %s\n", verbs[acl->verb], acl_name);
4185 /* DISCARD and DROP can happen only from a nested ACL condition, and
4186 DISCARD can happen only for an "accept" or "discard" verb. */
4189 HDEBUG(D_acl) debug_printf("%s: condition test yielded \"discard\" in %s\n",
4190 verbs[acl->verb], acl_name);
4194 HDEBUG(D_acl) debug_printf("%s: condition test yielded \"drop\" in %s\n",
4195 verbs[acl->verb], acl_name);
4199 /* At this point, cond for most verbs is either OK or FAIL or (as a result of
4200 a nested ACL condition) FAIL_DROP. However, for WARN, cond may be DEFER, and
4201 for ACCEPT and DISCARD, it may be DISCARD after a nested ACL call. */
4206 if (cond == OK || cond == DISCARD)
4208 HDEBUG(D_acl) debug_printf("end of %s: ACCEPT\n", acl_name);
4213 HDEBUG(D_acl) debug_printf("accept: endpass encountered - denying access\n");
4221 HDEBUG(D_acl) debug_printf("end of %s: DEFER\n", acl_name);
4222 if (acl_quit_check) goto badquit;
4223 acl_temp_details = TRUE;
4231 HDEBUG(D_acl) debug_printf("end of %s: DENY\n", acl_name);
4232 if (acl_quit_check) goto badquit;
4238 if (cond == OK || cond == DISCARD)
4240 HDEBUG(D_acl) debug_printf("end of %s: DISCARD\n", acl_name);
4241 if (acl_quit_check) goto badquit;
4246 HDEBUG(D_acl) debug_printf("discard: endpass encountered - denying access\n");
4254 HDEBUG(D_acl) debug_printf("end of %s: DROP\n", acl_name);
4255 if (acl_quit_check) goto badquit;
4263 HDEBUG(D_acl) debug_printf("end of %s: not OK\n", acl_name);
4264 if (acl_quit_check) goto badquit;
4271 acl_warn(where, *user_msgptr, *log_msgptr);
4272 else if (cond == DEFER && LOGGING(acl_warn_skipped))
4273 log_write(0, LOG_MAIN, "%s Warning: ACL \"warn\" statement skipped: "
4274 "condition test deferred%s%s", host_and_ident(TRUE),
4275 (*log_msgptr == NULL)? US"" : US": ",
4276 (*log_msgptr == NULL)? US"" : *log_msgptr);
4277 *log_msgptr = *user_msgptr = NULL; /* In case implicit DENY follows */
4281 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown verb %d",
4286 /* Pass to the next ACL item */
4291 /* We have reached the end of the ACL. This is an implicit DENY. */
4293 HDEBUG(D_acl) debug_printf("end of %s: implicit DENY\n", acl_name);
4297 *log_msgptr = string_sprintf("QUIT or not-QUIT teplevel ACL may not fail "
4298 "('%s' verb used incorrectly)", verbs[acl->verb]);
4305 /* Same args as acl_check_internal() above, but the string s is
4306 the name of an ACL followed optionally by up to 9 space-separated arguments.
4307 The name and args are separately expanded. Args go into $acl_arg globals. */
4309 acl_check_wargs(int where, address_item *addr, const uschar *s, int level,
4310 uschar **user_msgptr, uschar **log_msgptr)
4313 uschar * tmp_arg[9]; /* must match acl_arg[] */
4314 uschar * sav_arg[9]; /* must match acl_arg[] */
4320 if (!(tmp = string_dequote(&s)) || !(name = expand_string(tmp)))
4323 for (i = 0; i < 9; i++)
4325 while (*s && isspace(*s)) s++;
4327 if (!(tmp = string_dequote(&s)) || !(tmp_arg[i] = expand_string(tmp)))
4334 sav_narg = acl_narg;
4336 for (i = 0; i < acl_narg; i++)
4338 sav_arg[i] = acl_arg[i];
4339 acl_arg[i] = tmp_arg[i];
4343 sav_arg[i] = acl_arg[i];
4344 acl_arg[i++] = NULL;
4347 ret = acl_check_internal(where, addr, name, level, user_msgptr, log_msgptr);
4349 acl_narg = sav_narg;
4350 for (i = 0; i < 9; i++) acl_arg[i] = sav_arg[i];
4354 if (expand_string_forcedfail) return ERROR;
4355 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s",
4356 tmp, expand_string_message);
4357 return search_find_defer?DEFER:ERROR;
4362 /*************************************************
4363 * Check access using an ACL *
4364 *************************************************/
4366 /* Alternate interface for ACL, used by expansions */
4368 acl_eval(int where, uschar *s, uschar **user_msgptr, uschar **log_msgptr)
4371 address_item *addr = NULL;
4373 *user_msgptr = *log_msgptr = NULL;
4374 sender_verified_failed = NULL;
4375 ratelimiters_cmd = NULL;
4376 log_reject_target = LOG_MAIN|LOG_REJECT;
4378 if (where == ACL_WHERE_RCPT)
4380 adb = address_defaults;
4382 addr->address = expand_string(US"$local_part@$domain");
4383 addr->domain = deliver_domain;
4384 addr->local_part = deliver_localpart;
4385 addr->cc_local_part = deliver_localpart;
4386 addr->lc_local_part = deliver_localpart;
4389 return acl_check_internal(where, addr, s, 0, user_msgptr, log_msgptr);
4394 /* This is the external interface for ACL checks. It sets up an address and the
4395 expansions for $domain and $local_part when called after RCPT, then calls
4396 acl_check_internal() to do the actual work.
4399 where ACL_WHERE_xxxx indicating where called from
4400 recipient RCPT address for RCPT check, else NULL
4401 s the input string; NULL is the same as an empty ACL => DENY
4402 user_msgptr where to put a user error (for SMTP response)
4403 log_msgptr where to put a logging message (not for SMTP response)
4405 Returns: OK access is granted by an ACCEPT verb
4406 DISCARD access is granted by a DISCARD verb
4407 FAIL access is denied
4408 FAIL_DROP access is denied; drop the connection
4409 DEFER can't tell at the moment
4412 int acl_where = ACL_WHERE_UNKNOWN;
4415 acl_check(int where, uschar *recipient, uschar *s, uschar **user_msgptr,
4416 uschar **log_msgptr)
4420 address_item *addr = NULL;
4422 *user_msgptr = *log_msgptr = NULL;
4423 sender_verified_failed = NULL;
4424 ratelimiters_cmd = NULL;
4425 log_reject_target = LOG_MAIN|LOG_REJECT;
4427 #ifndef DISABLE_PRDR
4428 if (where==ACL_WHERE_RCPT || where==ACL_WHERE_VRFY || where==ACL_WHERE_PRDR)
4430 if (where==ACL_WHERE_RCPT || where==ACL_WHERE_VRFY)
4433 adb = address_defaults;
4435 addr->address = recipient;
4436 if (deliver_split_address(addr) == DEFER)
4438 *log_msgptr = US"defer in percent_hack_domains check";
4442 if ((addr->prop.utf8_msg = message_smtputf8))
4444 addr->prop.utf8_downcvt = message_utf8_downconvert == 1;
4445 addr->prop.utf8_downcvt_maybe = message_utf8_downconvert == -1;
4448 deliver_domain = addr->domain;
4449 deliver_localpart = addr->local_part;
4453 rc = acl_check_internal(where, addr, s, 0, user_msgptr, log_msgptr);
4454 acl_where = ACL_WHERE_UNKNOWN;
4456 /* Cutthrough - if requested,
4457 and WHERE_RCPT and not yet opened conn as result of recipient-verify,
4458 and rcpt acl returned accept,
4459 and first recipient (cancel on any subsequents)
4460 open one now and run it up to RCPT acceptance.
4461 A failed verify should cancel cutthrough request,
4462 and will pass the fail to the originator.
4463 Initial implementation: dual-write to spool.
4464 Assume the rxd datastream is now being copied byte-for-byte to an open cutthrough connection.
4466 Cease cutthrough copy on rxd final dot; do not send one.
4468 On a data acl, if not accept and a cutthrough conn is open, hard-close it (no SMTP niceness).
4470 On data acl accept, terminate the dataphase on an open cutthrough conn. If accepted or
4471 perm-rejected, reflect that to the original sender - and dump the spooled copy.
4472 If temp-reject, close the conn (and keep the spooled copy).
4473 If conn-failure, no action (and keep the spooled copy).
4477 case ACL_WHERE_RCPT:
4478 #ifndef DISABLE_PRDR
4479 case ACL_WHERE_PRDR:
4481 if (host_checking_callout) /* -bhc mode */
4482 cancel_cutthrough_connection("host-checking mode");
4483 else if (rc == OK && cutthrough.delivery && rcpt_count > cutthrough.nrcpt)
4484 rc = open_cutthrough_connection(addr);
4487 case ACL_WHERE_PREDATA:
4489 cutthrough_predata();
4491 cancel_cutthrough_connection("predata acl not ok");
4494 case ACL_WHERE_QUIT:
4495 case ACL_WHERE_NOTQUIT:
4496 cancel_cutthrough_connection("quit or notquit");
4503 deliver_domain = deliver_localpart = deliver_address_data =
4504 sender_address_data = NULL;
4506 /* A DISCARD response is permitted only for message ACLs, excluding the PREDATA
4507 ACL, which is really in the middle of an SMTP command. */
4511 if (where > ACL_WHERE_NOTSMTP || where == ACL_WHERE_PREDATA)
4513 log_write(0, LOG_MAIN|LOG_PANIC, "\"discard\" verb not allowed in %s "
4514 "ACL", acl_wherenames[where]);
4520 /* A DROP response is not permitted from MAILAUTH */
4522 if (rc == FAIL_DROP && where == ACL_WHERE_MAILAUTH)
4524 log_write(0, LOG_MAIN|LOG_PANIC, "\"drop\" verb not allowed in %s "
4525 "ACL", acl_wherenames[where]);
4529 /* Before giving a response, take a look at the length of any user message, and
4530 split it up into multiple lines if possible. */
4532 *user_msgptr = string_split_message(*user_msgptr);
4533 if (fake_response != OK)
4534 fake_response_text = string_split_message(fake_response_text);
4540 /*************************************************
4541 * Create ACL variable *
4542 *************************************************/
4544 /* Create an ACL variable or reuse an existing one. ACL variables are in a
4545 binary tree (see tree.c) with acl_var_c and acl_var_m as root nodes.
4548 name pointer to the variable's name, starting with c or m
4550 Returns the pointer to variable's tree node
4554 acl_var_create(uschar *name)
4556 tree_node *node, **root;
4557 root = (name[0] == 'c')? &acl_var_c : &acl_var_m;
4558 node = tree_search(*root, name);
4561 node = store_get(sizeof(tree_node) + Ustrlen(name));
4562 Ustrcpy(node->name, name);
4563 (void)tree_insertnode(root, node);
4565 node->data.ptr = NULL;
4571 /*************************************************
4572 * Write an ACL variable in spool format *
4573 *************************************************/
4575 /* This function is used as a callback for tree_walk when writing variables to
4576 the spool file. To retain spool file compatibility, what is written is -aclc or
4577 -aclm followed by the rest of the name and the data length, space separated,
4578 then the value itself, starting on a new line, and terminated by an additional
4579 newline. When we had only numbered ACL variables, the first line might look
4580 like this: "-aclc 5 20". Now it might be "-aclc foo 20" for the variable called
4584 name of the variable
4585 value of the variable
4586 ctx FILE pointer (as a void pointer)
4592 acl_var_write(uschar *name, uschar *value, void *ctx)
4594 FILE *f = (FILE *)ctx;
4595 fprintf(f, "-acl%c %s %d\n%s\n", name[0], name+1, Ustrlen(value), value);