1 /* $Cambridge: exim/src/src/acl.c,v 1.83 2009/06/10 07:34:04 tom Exp $ */
3 /*************************************************
4 * Exim - an Internet mail transport agent *
5 *************************************************/
7 /* Copyright (c) University of Cambridge 1995 - 2007 */
8 /* See the file NOTICE for conditions of use and distribution. */
10 /* Code for handling Access Control Lists (ACLs) */
15 /* Default callout timeout */
17 #define CALLOUT_TIMEOUT_DEFAULT 30
19 /* ACL verb codes - keep in step with the table of verbs that follows */
21 enum { ACL_ACCEPT, ACL_DEFER, ACL_DENY, ACL_DISCARD, ACL_DROP, ACL_REQUIRE,
26 static uschar *verbs[] =
27 { US"accept", US"defer", US"deny", US"discard", US"drop", US"require",
30 /* For each verb, the conditions for which "message" or "log_message" are used
31 are held as a bitmap. This is to avoid expanding the strings unnecessarily. For
32 "accept", the FAIL case is used only after "endpass", but that is selected in
35 static int msgcond[] = {
36 (1<<OK) | (1<<FAIL) | (1<<FAIL_DROP), /* accept */
39 (1<<OK) | (1<<FAIL) | (1<<FAIL_DROP), /* discard */
41 (1<<FAIL) | (1<<FAIL_DROP), /* require */
45 /* ACL condition and modifier codes - keep in step with the table that
46 follows, and the cond_expand_at_top and uschar cond_modifiers tables lower
52 #ifdef EXPERIMENTAL_BRIGHTMAIL
58 #ifdef EXPERIMENTAL_DCC
61 #ifdef WITH_CONTENT_SCAN
65 #ifdef WITH_OLD_DEMIME
79 ACLC_LOG_REJECT_TARGET,
81 #ifdef WITH_CONTENT_SCAN
85 #ifdef WITH_CONTENT_SCAN
90 #ifdef WITH_CONTENT_SCAN
96 #ifdef WITH_CONTENT_SCAN
99 #ifdef EXPERIMENTAL_SPF
105 /* ACL conditions/modifiers: "delay", "control", "continue", "endpass",
106 "message", "log_message", "log_reject_target", "logwrite", and "set" are
107 modifiers that look like conditions but always return TRUE. They are used for
108 their side effects. */
110 static uschar *conditions[] = {
114 #ifdef EXPERIMENTAL_BRIGHTMAIL
120 #ifdef EXPERIMENTAL_DCC
123 #ifdef WITH_CONTENT_SCAN
127 #ifdef WITH_OLD_DEMIME
141 US"log_reject_target",
143 #ifdef WITH_CONTENT_SCAN
147 #ifdef WITH_CONTENT_SCAN
152 #ifdef WITH_CONTENT_SCAN
155 US"sender_domains", US"senders", US"set",
156 #ifdef WITH_CONTENT_SCAN
159 #ifdef EXPERIMENTAL_SPF
166 /* Return values from decode_control(); keep in step with the table of names
170 CONTROL_AUTH_UNADVERTISED,
171 #ifdef EXPERIMENTAL_BRIGHTMAIL
178 CONTROL_CASEFUL_LOCAL_PART,
179 CONTROL_CASELOWER_LOCAL_PART,
180 CONTROL_ENFORCE_SYNC,
181 CONTROL_NO_ENFORCE_SYNC,
185 CONTROL_SUPPRESS_LOCAL_FIXUPS,
186 #ifdef WITH_CONTENT_SCAN
187 CONTROL_NO_MBOX_UNSPOOL,
191 CONTROL_NO_MULTILINE,
192 CONTROL_NO_PIPELINING,
193 CONTROL_NO_DELAY_FLUSH,
194 CONTROL_NO_CALLOUT_FLUSH
197 /* ACL control names; keep in step with the table above! This list is used for
198 turning ids into names. The actual list of recognized names is in the variable
199 control_def controls_list[] below. The fact that there are two lists is a mess
200 and should be tidied up. */
202 static uschar *controls[] = {
203 US"allow_auth_unadvertised",
204 #ifdef EXPERIMENTAL_BRIGHTMAIL
208 US"dkim_disable_verify",
211 US"caseful_local_part",
212 US"caselower_local_part",
218 US"suppress_local_fixups",
219 #ifdef WITH_CONTENT_SCAN
224 US"no_multiline_responses",
230 /* Flags to indicate for which conditions/modifiers a string expansion is done
231 at the outer level. In the other cases, expansion already occurs in the
232 checking functions. */
234 static uschar cond_expand_at_top[] = {
236 TRUE, /* add_header */
237 FALSE, /* authenticated */
238 #ifdef EXPERIMENTAL_BRIGHTMAIL
239 TRUE, /* bmi_optin */
241 TRUE, /* condition */
244 #ifdef EXPERIMENTAL_DCC
247 #ifdef WITH_CONTENT_SCAN
251 #ifdef WITH_OLD_DEMIME
255 TRUE, /* dkim_signers */
256 TRUE, /* dkim_status */
260 FALSE, /* encrypted */
263 FALSE, /* local_parts */
264 TRUE, /* log_message */
265 TRUE, /* log_reject_target */
267 #ifdef WITH_CONTENT_SCAN
271 #ifdef WITH_CONTENT_SCAN
272 TRUE, /* mime_regex */
274 TRUE, /* ratelimit */
275 FALSE, /* recipients */
276 #ifdef WITH_CONTENT_SCAN
279 FALSE, /* sender_domains */
282 #ifdef WITH_CONTENT_SCAN
285 #ifdef EXPERIMENTAL_SPF
287 TRUE, /* spf_guess */
292 /* Flags to identify the modifiers */
294 static uschar cond_modifiers[] = {
296 TRUE, /* add_header */
297 FALSE, /* authenticated */
298 #ifdef EXPERIMENTAL_BRIGHTMAIL
299 TRUE, /* bmi_optin */
301 FALSE, /* condition */
304 #ifdef EXPERIMENTAL_DCC
307 #ifdef WITH_CONTENT_SCAN
311 #ifdef WITH_OLD_DEMIME
315 FALSE, /* dkim_signers */
316 FALSE, /* dkim_status */
318 FALSE, /* dnslists */
320 FALSE, /* encrypted */
323 FALSE, /* local_parts */
324 TRUE, /* log_message */
325 TRUE, /* log_reject_target */
327 #ifdef WITH_CONTENT_SCAN
331 #ifdef WITH_CONTENT_SCAN
332 FALSE, /* mime_regex */
334 FALSE, /* ratelimit */
335 FALSE, /* recipients */
336 #ifdef WITH_CONTENT_SCAN
339 FALSE, /* sender_domains */
342 #ifdef WITH_CONTENT_SCAN
345 #ifdef EXPERIMENTAL_SPF
347 FALSE, /* spf_guess */
352 /* Bit map vector of which conditions and modifiers are not allowed at certain
353 times. For each condition and modifier, there's a bitmap of dis-allowed times.
354 For some, it is easier to specify the negation of a small number of allowed
357 static unsigned int cond_forbids[] = {
361 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* add_header */
362 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
363 (1<<ACL_WHERE_MIME)|(1<<ACL_WHERE_NOTSMTP)|
364 (1<<ACL_WHERE_NOTSMTP_START)),
366 (1<<ACL_WHERE_NOTSMTP)| /* authenticated */
367 (1<<ACL_WHERE_NOTSMTP_START)|
368 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO),
370 #ifdef EXPERIMENTAL_BRIGHTMAIL
371 (1<<ACL_WHERE_AUTH)| /* bmi_optin */
372 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
373 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_MIME)|
374 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
375 (1<<ACL_WHERE_MAILAUTH)|
376 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
377 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_PREDATA)|
378 (1<<ACL_WHERE_NOTSMTP_START),
385 /* Certain types of control are always allowed, so we let it through
386 always and check in the control processing itself. */
390 #ifdef EXPERIMENTAL_DCC
392 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)), /* dcc */
395 #ifdef WITH_CONTENT_SCAN
397 ~(1<<ACL_WHERE_MIME), /* decode */
400 (1<<ACL_WHERE_NOTQUIT), /* delay */
402 #ifdef WITH_OLD_DEMIME
404 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)), /* demime */
409 ~(1<<ACL_WHERE_DKIM), /* dkim_signers */
412 ~(1<<ACL_WHERE_DKIM), /* dkim_status */
415 (1<<ACL_WHERE_NOTSMTP)| /* dnslists */
416 (1<<ACL_WHERE_NOTSMTP_START),
419 ~(1<<ACL_WHERE_RCPT), /* domains */
421 (1<<ACL_WHERE_NOTSMTP)| /* encrypted */
422 (1<<ACL_WHERE_CONNECT)|
423 (1<<ACL_WHERE_NOTSMTP_START)|
428 (1<<ACL_WHERE_NOTSMTP)| /* hosts */
429 (1<<ACL_WHERE_NOTSMTP_START),
432 ~(1<<ACL_WHERE_RCPT), /* local_parts */
436 0, /* log_reject_target */
440 #ifdef WITH_CONTENT_SCAN
442 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)), /* malware */
447 #ifdef WITH_CONTENT_SCAN
449 ~(1<<ACL_WHERE_MIME), /* mime_regex */
455 ~(1<<ACL_WHERE_RCPT), /* recipients */
457 #ifdef WITH_CONTENT_SCAN
459 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* regex */
460 (1<<ACL_WHERE_MIME)),
463 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* sender_domains */
465 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
466 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
467 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
469 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* senders */
471 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
472 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
473 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
477 #ifdef WITH_CONTENT_SCAN
479 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)), /* spam */
482 #ifdef EXPERIMENTAL_SPF
483 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* spf */
485 (1<<ACL_WHERE_MAILAUTH)|
486 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
487 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY)|
488 (1<<ACL_WHERE_NOTSMTP)|
489 (1<<ACL_WHERE_NOTSMTP_START),
491 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* spf_guess */
493 (1<<ACL_WHERE_MAILAUTH)|
494 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
495 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY)|
496 (1<<ACL_WHERE_NOTSMTP)|
497 (1<<ACL_WHERE_NOTSMTP_START),
500 /* Certain types of verify are always allowed, so we let it through
501 always and check in the verify function itself */
507 /* Bit map vector of which controls are not allowed at certain times. For
508 each control, there's a bitmap of dis-allowed times. For some, it is easier to
509 specify the negation of a small number of allowed times. */
511 static unsigned int control_forbids[] = {
513 ~((1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)), /* allow_auth_unadvertised */
515 #ifdef EXPERIMENTAL_BRIGHTMAIL
520 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* dkim_disable_verify */
521 (1<<ACL_WHERE_NOTSMTP_START),
527 ~(1<<ACL_WHERE_RCPT), /* caseful_local_part */
530 ~(1<<ACL_WHERE_RCPT), /* caselower_local_part */
532 (1<<ACL_WHERE_NOTSMTP)| /* enforce_sync */
533 (1<<ACL_WHERE_NOTSMTP_START),
535 (1<<ACL_WHERE_NOTSMTP)| /* no_enforce_sync */
536 (1<<ACL_WHERE_NOTSMTP_START),
539 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* freeze */
540 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
541 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)),
544 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* queue_only */
545 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
546 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)),
549 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* submission */
550 (1<<ACL_WHERE_PREDATA)),
553 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* suppress_local_fixups */
554 (1<<ACL_WHERE_PREDATA)|
555 (1<<ACL_WHERE_NOTSMTP_START)),
557 #ifdef WITH_CONTENT_SCAN
559 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* no_mbox_unspool */
560 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
561 (1<<ACL_WHERE_MIME)),
565 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakedefer */
566 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
567 (1<<ACL_WHERE_MIME)),
570 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakereject */
571 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
572 (1<<ACL_WHERE_MIME)),
574 (1<<ACL_WHERE_NOTSMTP)| /* no_multiline */
575 (1<<ACL_WHERE_NOTSMTP_START),
577 (1<<ACL_WHERE_NOTSMTP)| /* no_pipelining */
578 (1<<ACL_WHERE_NOTSMTP_START),
580 (1<<ACL_WHERE_NOTSMTP)| /* no_delay_flush */
581 (1<<ACL_WHERE_NOTSMTP_START),
583 (1<<ACL_WHERE_NOTSMTP)| /* no_callout_flush */
584 (1<<ACL_WHERE_NOTSMTP_START)
587 /* Structure listing various control arguments, with their characteristics. */
589 typedef struct control_def {
591 int value; /* CONTROL_xxx value */
592 BOOL has_option; /* Has /option(s) following */
595 static control_def controls_list[] = {
596 { US"allow_auth_unadvertised", CONTROL_AUTH_UNADVERTISED, FALSE },
597 #ifdef EXPERIMENTAL_BRIGHTMAIL
598 { US"bmi_run", CONTROL_BMI_RUN, FALSE },
601 { US"dkim_disable_verify", CONTROL_DKIM_VERIFY, FALSE },
603 { US"caseful_local_part", CONTROL_CASEFUL_LOCAL_PART, FALSE },
604 { US"caselower_local_part", CONTROL_CASELOWER_LOCAL_PART, FALSE },
605 { US"enforce_sync", CONTROL_ENFORCE_SYNC, FALSE },
606 { US"freeze", CONTROL_FREEZE, TRUE },
607 { US"no_callout_flush", CONTROL_NO_CALLOUT_FLUSH, FALSE },
608 { US"no_delay_flush", CONTROL_NO_DELAY_FLUSH, FALSE },
609 { US"no_enforce_sync", CONTROL_NO_ENFORCE_SYNC, FALSE },
610 { US"no_multiline_responses", CONTROL_NO_MULTILINE, FALSE },
611 { US"no_pipelining", CONTROL_NO_PIPELINING, FALSE },
612 { US"queue_only", CONTROL_QUEUE_ONLY, FALSE },
613 #ifdef WITH_CONTENT_SCAN
614 { US"no_mbox_unspool", CONTROL_NO_MBOX_UNSPOOL, FALSE },
616 { US"fakedefer", CONTROL_FAKEDEFER, TRUE },
617 { US"fakereject", CONTROL_FAKEREJECT, TRUE },
618 { US"submission", CONTROL_SUBMISSION, TRUE },
619 { US"suppress_local_fixups", CONTROL_SUPPRESS_LOCAL_FIXUPS, FALSE }
622 /* Support data structures for Client SMTP Authorization. acl_verify_csa()
623 caches its result in a tree to avoid repeated DNS queries. The result is an
624 integer code which is used as an index into the following tables of
625 explanatory strings and verification return codes. */
627 static tree_node *csa_cache = NULL;
629 enum { CSA_UNKNOWN, CSA_OK, CSA_DEFER_SRV, CSA_DEFER_ADDR,
630 CSA_FAIL_EXPLICIT, CSA_FAIL_DOMAIN, CSA_FAIL_NOADDR, CSA_FAIL_MISMATCH };
632 /* The acl_verify_csa() return code is translated into an acl_verify() return
633 code using the following table. It is OK unless the client is definitely not
634 authorized. This is because CSA is supposed to be optional for sending sites,
635 so recipients should not be too strict about checking it - especially because
636 DNS problems are quite likely to occur. It's possible to use $csa_status in
637 further ACL conditions to distinguish ok, unknown, and defer if required, but
638 the aim is to make the usual configuration simple. */
640 static int csa_return_code[] = {
642 FAIL, FAIL, FAIL, FAIL
645 static uschar *csa_status_string[] = {
646 US"unknown", US"ok", US"defer", US"defer",
647 US"fail", US"fail", US"fail", US"fail"
650 static uschar *csa_reason_string[] = {
653 US"deferred (SRV lookup failed)",
654 US"deferred (target address lookup failed)",
655 US"failed (explicit authorization required)",
656 US"failed (host name not authorized)",
657 US"failed (no authorized addresses)",
658 US"failed (client address mismatch)"
661 /* Enable recursion between acl_check_internal() and acl_check_condition() */
663 static int acl_check_internal(int, address_item *, uschar *, int, uschar **,
667 /*************************************************
668 * Pick out name from list *
669 *************************************************/
671 /* Use a binary chop method
678 Returns: offset in list, or -1 if not found
682 acl_checkname(uschar *name, uschar **list, int end)
688 int mid = (start + end)/2;
689 int c = Ustrcmp(name, list[mid]);
690 if (c == 0) return mid;
691 if (c < 0) end = mid; else start = mid + 1;
698 /*************************************************
699 * Read and parse one ACL *
700 *************************************************/
702 /* This function is called both from readconf in order to parse the ACLs in the
703 configuration file, and also when an ACL is encountered dynamically (e.g. as
704 the result of an expansion). It is given a function to call in order to
705 retrieve the lines of the ACL. This function handles skipping comments and
706 blank lines (where relevant).
709 func function to get next line of ACL
710 error where to put an error message
712 Returns: pointer to ACL, or NULL
713 NULL can be legal (empty ACL); in this case error will be NULL
717 acl_read(uschar *(*func)(void), uschar **error)
719 acl_block *yield = NULL;
720 acl_block **lastp = &yield;
721 acl_block *this = NULL;
722 acl_condition_block *cond;
723 acl_condition_block **condp = NULL;
728 while ((s = (*func)()) != NULL)
731 BOOL negated = FALSE;
732 uschar *saveline = s;
735 /* Conditions (but not verbs) are allowed to be negated by an initial
738 while (isspace(*s)) s++;
745 /* Read the name of a verb or a condition, or the start of a new ACL, which
746 can be started by a name, or by a macro definition. */
748 s = readconf_readname(name, sizeof(name), s);
749 if (*s == ':' || (isupper(name[0]) && *s == '=')) return yield;
751 /* If a verb is unrecognized, it may be another condition or modifier that
752 continues the previous verb. */
754 v = acl_checkname(name, verbs, sizeof(verbs)/sizeof(char *));
759 *error = string_sprintf("unknown ACL verb \"%s\" in \"%s\"", name,
771 *error = string_sprintf("malformed ACL line \"%s\"", saveline);
774 this = store_get(sizeof(acl_block));
776 lastp = &(this->next);
779 this->condition = NULL;
780 condp = &(this->condition);
781 if (*s == 0) continue; /* No condition on this line */
787 s = readconf_readname(name, sizeof(name), s); /* Condition name */
790 /* Handle a condition or modifier. */
792 c = acl_checkname(name, conditions, sizeof(conditions)/sizeof(char *));
795 *error = string_sprintf("unknown ACL condition/modifier in \"%s\"",
800 /* The modifiers may not be negated */
802 if (negated && cond_modifiers[c])
804 *error = string_sprintf("ACL error: negation is not allowed with "
805 "\"%s\"", conditions[c]);
809 /* ENDPASS may occur only with ACCEPT or DISCARD. */
811 if (c == ACLC_ENDPASS &&
812 this->verb != ACL_ACCEPT &&
813 this->verb != ACL_DISCARD)
815 *error = string_sprintf("ACL error: \"%s\" is not allowed with \"%s\"",
816 conditions[c], verbs[this->verb]);
820 cond = store_get(sizeof(acl_condition_block));
823 cond->u.negated = negated;
826 condp = &(cond->next);
828 /* The "set" modifier is different in that its argument is "name=value"
829 rather than just a value, and we can check the validity of the name, which
830 gives us a variable name to insert into the data block. The original ACL
831 variable names were acl_c0 ... acl_c9 and acl_m0 ... acl_m9. This was
832 extended to 20 of each type, but after that people successfully argued for
833 arbitrary names. In the new scheme, the names must start with acl_c or acl_m.
834 After that, we allow alphanumerics and underscores, but the first character
835 after c or m must be a digit or an underscore. This retains backwards
842 if (Ustrncmp(s, "acl_c", 5) != 0 &&
843 Ustrncmp(s, "acl_m", 5) != 0)
845 *error = string_sprintf("invalid variable name after \"set\" in ACL "
846 "modifier \"set %s\" (must start \"acl_c\" or \"acl_m\")", s);
851 if (!isdigit(*endptr) && *endptr != '_')
853 *error = string_sprintf("invalid variable name after \"set\" in ACL "
854 "modifier \"set %s\" (digit or underscore must follow acl_c or acl_m)",
859 while (*endptr != 0 && *endptr != '=' && !isspace(*endptr))
861 if (!isalnum(*endptr) && *endptr != '_')
863 *error = string_sprintf("invalid character \"%c\" in variable name "
864 "in ACL modifier \"set %s\"", *endptr, s);
870 cond->u.varname = string_copyn(s + 4, endptr - s - 4);
872 while (isspace(*s)) s++;
875 /* For "set", we are now positioned for the data. For the others, only
876 "endpass" has no data */
878 if (c != ACLC_ENDPASS)
882 *error = string_sprintf("\"=\" missing after ACL \"%s\" %s", name,
883 cond_modifiers[c]? US"modifier" : US"condition");
886 while (isspace(*s)) s++;
887 cond->arg = string_copy(s);
896 /*************************************************
897 * Set up added header line(s) *
898 *************************************************/
900 /* This function is called by the add_header modifier, and also from acl_warn()
901 to implement the now-deprecated way of adding header lines using "message" on a
902 "warn" verb. The argument is treated as a sequence of header lines which are
903 added to a chain, provided there isn't an identical one already there.
905 Argument: string of header lines
910 setup_header(uschar *hstring)
913 int hlen = Ustrlen(hstring);
915 /* An empty string does nothing; otherwise add a final newline if necessary. */
917 if (hlen <= 0) return;
918 if (hstring[hlen-1] != '\n') hstring = string_sprintf("%s\n", hstring);
920 /* Loop for multiple header lines, taking care about continuations */
922 for (p = q = hstring; *p != 0; )
925 int newtype = htype_add_bot;
926 header_line **hptr = &acl_added_headers;
928 /* Find next header line within the string */
932 q = Ustrchr(q, '\n');
933 if (*(++q) != ' ' && *q != '\t') break;
936 /* If the line starts with a colon, interpret the instruction for where to
937 add it. This temporarily sets up a new type. */
941 if (strncmpic(p, US":after_received:", 16) == 0)
943 newtype = htype_add_rec;
946 else if (strncmpic(p, US":at_start_rfc:", 14) == 0)
948 newtype = htype_add_rfc;
951 else if (strncmpic(p, US":at_start:", 10) == 0)
953 newtype = htype_add_top;
956 else if (strncmpic(p, US":at_end:", 8) == 0)
958 newtype = htype_add_bot;
961 while (*p == ' ' || *p == '\t') p++;
964 /* See if this line starts with a header name, and if not, add X-ACL-Warn:
965 to the front of it. */
967 for (s = p; s < q - 1; s++)
969 if (*s == ':' || !isgraph(*s)) break;
972 s = string_sprintf("%s%.*s", (*s == ':')? "" : "X-ACL-Warn: ", q - p, p);
975 /* See if this line has already been added */
977 while (*hptr != NULL)
979 if (Ustrncmp((*hptr)->text, s, hlen) == 0) break;
980 hptr = &((*hptr)->next);
983 /* Add if not previously present */
987 header_line *h = store_get(sizeof(header_line));
996 /* Advance for next header line within the string */
1005 /*************************************************
1007 *************************************************/
1009 /* This function is called when a WARN verb's conditions are true. It adds to
1010 the message's headers, and/or writes information to the log. In each case, this
1011 only happens once (per message for headers, per connection for log).
1013 ** NOTE: The header adding action using the "message" setting is historic, and
1014 its use is now deprecated. The new add_header modifier should be used instead.
1017 where ACL_WHERE_xxxx indicating which ACL this is
1018 user_message message for adding to headers
1019 log_message message for logging, if different
1025 acl_warn(int where, uschar *user_message, uschar *log_message)
1027 if (log_message != NULL && log_message != user_message)
1030 string_item *logged;
1032 text = string_sprintf("%s Warning: %s", host_and_ident(TRUE),
1033 string_printing(log_message));
1035 /* If a sender verification has failed, and the log message is "sender verify
1036 failed", add the failure message. */
1038 if (sender_verified_failed != NULL &&
1039 sender_verified_failed->message != NULL &&
1040 strcmpic(log_message, US"sender verify failed") == 0)
1041 text = string_sprintf("%s: %s", text, sender_verified_failed->message);
1043 /* Search previously logged warnings. They are kept in malloc
1044 store so they can be freed at the start of a new message. */
1046 for (logged = acl_warn_logged; logged != NULL; logged = logged->next)
1047 if (Ustrcmp(logged->text, text) == 0) break;
1051 int length = Ustrlen(text) + 1;
1052 log_write(0, LOG_MAIN, "%s", text);
1053 logged = store_malloc(sizeof(string_item) + length);
1054 logged->text = (uschar *)logged + sizeof(string_item);
1055 memcpy(logged->text, text, length);
1056 logged->next = acl_warn_logged;
1057 acl_warn_logged = logged;
1061 /* If there's no user message, we are done. */
1063 if (user_message == NULL) return;
1065 /* If this isn't a message ACL, we can't do anything with a user message.
1068 if (where > ACL_WHERE_NOTSMTP)
1070 log_write(0, LOG_MAIN|LOG_PANIC, "ACL \"warn\" with \"message\" setting "
1071 "found in a non-message (%s) ACL: cannot specify header lines here: "
1072 "message ignored", acl_wherenames[where]);
1076 /* The code for setting up header lines is now abstracted into a separate
1077 function so that it can be used for the add_header modifier as well. */
1079 setup_header(user_message);
1084 /*************************************************
1085 * Verify and check reverse DNS *
1086 *************************************************/
1088 /* Called from acl_verify() below. We look up the host name(s) of the client IP
1089 address if this has not yet been done. The host_name_lookup() function checks
1090 that one of these names resolves to an address list that contains the client IP
1091 address, so we don't actually have to do the check here.
1094 user_msgptr pointer for user message
1095 log_msgptr pointer for log message
1097 Returns: OK verification condition succeeded
1098 FAIL verification failed
1099 DEFER there was a problem verifying
1103 acl_verify_reverse(uschar **user_msgptr, uschar **log_msgptr)
1107 user_msgptr = user_msgptr; /* stop compiler warning */
1109 /* Previous success */
1111 if (sender_host_name != NULL) return OK;
1113 /* Previous failure */
1115 if (host_lookup_failed)
1117 *log_msgptr = string_sprintf("host lookup failed%s", host_lookup_msg);
1121 /* Need to do a lookup */
1124 debug_printf("looking up host name to force name/address consistency check\n");
1126 if ((rc = host_name_lookup()) != OK)
1128 *log_msgptr = (rc == DEFER)?
1129 US"host lookup deferred for reverse lookup check"
1131 string_sprintf("host lookup failed for reverse lookup check%s",
1133 return rc; /* DEFER or FAIL */
1136 host_build_sender_fullhost();
1142 /*************************************************
1143 * Check client IP address matches CSA target *
1144 *************************************************/
1146 /* Called from acl_verify_csa() below. This routine scans a section of a DNS
1147 response for address records belonging to the CSA target hostname. The section
1148 is specified by the reset argument, either RESET_ADDITIONAL or RESET_ANSWERS.
1149 If one of the addresses matches the client's IP address, then the client is
1150 authorized by CSA. If there are target IP addresses but none of them match
1151 then the client is using an unauthorized IP address. If there are no target IP
1152 addresses then the client cannot be using an authorized IP address. (This is
1153 an odd configuration - why didn't the SRV record have a weight of 1 instead?)
1156 dnsa the DNS answer block
1157 dnss a DNS scan block for us to use
1158 reset option specifing what portion to scan, as described above
1159 target the target hostname to use for matching RR names
1161 Returns: CSA_OK successfully authorized
1162 CSA_FAIL_MISMATCH addresses found but none matched
1163 CSA_FAIL_NOADDR no target addresses found
1167 acl_verify_csa_address(dns_answer *dnsa, dns_scan *dnss, int reset,
1173 BOOL target_found = FALSE;
1175 for (rr = dns_next_rr(dnsa, dnss, reset);
1177 rr = dns_next_rr(dnsa, dnss, RESET_NEXT))
1179 /* Check this is an address RR for the target hostname. */
1183 && rr->type != T_AAAA
1190 if (strcmpic(target, rr->name) != 0) continue;
1192 target_found = TRUE;
1194 /* Turn the target address RR into a list of textual IP addresses and scan
1195 the list. There may be more than one if it is an A6 RR. */
1197 for (da = dns_address_from_rr(dnsa, rr); da != NULL; da = da->next)
1199 /* If the client IP address matches the target IP address, it's good! */
1201 DEBUG(D_acl) debug_printf("CSA target address is %s\n", da->address);
1203 if (strcmpic(sender_host_address, da->address) == 0) return CSA_OK;
1207 /* If we found some target addresses but none of them matched, the client is
1208 using an unauthorized IP address, otherwise the target has no authorized IP
1211 if (target_found) return CSA_FAIL_MISMATCH;
1212 else return CSA_FAIL_NOADDR;
1217 /*************************************************
1218 * Verify Client SMTP Authorization *
1219 *************************************************/
1221 /* Called from acl_verify() below. This routine calls dns_lookup_special()
1222 to find the CSA SRV record corresponding to the domain argument, or
1223 $sender_helo_name if no argument is provided. It then checks that the
1224 client is authorized, and that its IP address corresponds to the SRV
1225 target's address by calling acl_verify_csa_address() above. The address
1226 should have been returned in the DNS response's ADDITIONAL section, but if
1227 not we perform another DNS lookup to get it.
1230 domain pointer to optional parameter following verify = csa
1232 Returns: CSA_UNKNOWN no valid CSA record found
1233 CSA_OK successfully authorized
1234 CSA_FAIL_* client is definitely not authorized
1235 CSA_DEFER_* there was a DNS problem
1239 acl_verify_csa(uschar *domain)
1243 int priority, weight, port;
1250 /* Work out the domain we are using for the CSA lookup. The default is the
1251 client's HELO domain. If the client has not said HELO, use its IP address
1252 instead. If it's a local client (exim -bs), CSA isn't applicable. */
1254 while (isspace(*domain) && *domain != '\0') ++domain;
1255 if (*domain == '\0') domain = sender_helo_name;
1256 if (domain == NULL) domain = sender_host_address;
1257 if (sender_host_address == NULL) return CSA_UNKNOWN;
1259 /* If we have an address literal, strip off the framing ready for turning it
1260 into a domain. The framing consists of matched square brackets possibly
1261 containing a keyword and a colon before the actual IP address. */
1263 if (domain[0] == '[')
1265 uschar *start = Ustrchr(domain, ':');
1266 if (start == NULL) start = domain;
1267 domain = string_copyn(start + 1, Ustrlen(start) - 2);
1270 /* Turn domains that look like bare IP addresses into domains in the reverse
1271 DNS. This code also deals with address literals and $sender_host_address. It's
1272 not quite kosher to treat bare domains such as EHLO 192.0.2.57 the same as
1273 address literals, but it's probably the most friendly thing to do. This is an
1274 extension to CSA, so we allow it to be turned off for proper conformance. */
1276 if (string_is_ip_address(domain, NULL) != 0)
1278 if (!dns_csa_use_reverse) return CSA_UNKNOWN;
1279 dns_build_reverse(domain, target);
1283 /* Find out if we've already done the CSA check for this domain. If we have,
1284 return the same result again. Otherwise build a new cached result structure
1285 for this domain. The name is filled in now, and the value is filled in when
1286 we return from this function. */
1288 t = tree_search(csa_cache, domain);
1289 if (t != NULL) return t->data.val;
1291 t = store_get_perm(sizeof(tree_node) + Ustrlen(domain));
1292 Ustrcpy(t->name, domain);
1293 (void)tree_insertnode(&csa_cache, t);
1295 /* Now we are ready to do the actual DNS lookup(s). */
1298 switch (dns_special_lookup(&dnsa, domain, T_CSA, &found))
1300 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1303 return t->data.val = CSA_DEFER_SRV;
1305 /* If we found nothing, the client's authorization is unknown. */
1309 return t->data.val = CSA_UNKNOWN;
1311 /* We got something! Go on to look at the reply in more detail. */
1317 /* Scan the reply for well-formed CSA SRV records. */
1319 for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS);
1321 rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT))
1323 if (rr->type != T_SRV) continue;
1325 /* Extract the numerical SRV fields (p is incremented) */
1328 GETSHORT(priority, p);
1329 GETSHORT(weight, p);
1333 debug_printf("CSA priority=%d weight=%d port=%d\n", priority, weight, port);
1335 /* Check the CSA version number */
1337 if (priority != 1) continue;
1339 /* If the domain does not have a CSA SRV record of its own (i.e. the domain
1340 found by dns_special_lookup() is a parent of the one we asked for), we check
1341 the subdomain assertions in the port field. At the moment there's only one
1342 assertion: legitimate SMTP clients are all explicitly authorized with CSA
1343 SRV records of their own. */
1345 if (found != domain)
1348 return t->data.val = CSA_FAIL_EXPLICIT;
1350 return t->data.val = CSA_UNKNOWN;
1353 /* This CSA SRV record refers directly to our domain, so we check the value
1354 in the weight field to work out the domain's authorization. 0 and 1 are
1355 unauthorized; 3 means the client is authorized but we can't check the IP
1356 address in order to authenticate it, so we treat it as unknown; values
1357 greater than 3 are undefined. */
1359 if (weight < 2) return t->data.val = CSA_FAIL_DOMAIN;
1361 if (weight > 2) continue;
1363 /* Weight == 2, which means the domain is authorized. We must check that the
1364 client's IP address is listed as one of the SRV target addresses. Save the
1365 target hostname then break to scan the additional data for its addresses. */
1367 (void)dn_expand(dnsa.answer, dnsa.answer + dnsa.answerlen, p,
1368 (DN_EXPAND_ARG4_TYPE)target, sizeof(target));
1370 DEBUG(D_acl) debug_printf("CSA target is %s\n", target);
1375 /* If we didn't break the loop then no appropriate records were found. */
1377 if (rr == NULL) return t->data.val = CSA_UNKNOWN;
1379 /* Do not check addresses if the target is ".", in accordance with RFC 2782.
1380 A target of "." indicates there are no valid addresses, so the client cannot
1381 be authorized. (This is an odd configuration because weight=2 target=. is
1382 equivalent to weight=1, but we check for it in order to keep load off the
1383 root name servers.) Note that dn_expand() turns "." into "". */
1385 if (Ustrcmp(target, "") == 0) return t->data.val = CSA_FAIL_NOADDR;
1387 /* Scan the additional section of the CSA SRV reply for addresses belonging
1388 to the target. If the name server didn't return any additional data (e.g.
1389 because it does not fully support SRV records), we need to do another lookup
1390 to obtain the target addresses; otherwise we have a definitive result. */
1392 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ADDITIONAL, target);
1393 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1395 /* The DNS lookup type corresponds to the IP version used by the client. */
1398 if (Ustrchr(sender_host_address, ':') != NULL)
1401 #endif /* HAVE_IPV6 */
1405 #if HAVE_IPV6 && defined(SUPPORT_A6)
1409 switch (dns_lookup(&dnsa, target, type, NULL))
1411 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1414 return t->data.val = CSA_DEFER_ADDR;
1416 /* If the query succeeded, scan the addresses and return the result. */
1419 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ANSWERS, target);
1420 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1421 /* else fall through */
1423 /* If the target has no IP addresses, the client cannot have an authorized
1424 IP address. However, if the target site uses A6 records (not AAAA records)
1425 we have to do yet another lookup in order to check them. */
1430 #if HAVE_IPV6 && defined(SUPPORT_A6)
1431 if (type == T_AAAA) { type = T_A6; goto DNS_LOOKUP_AGAIN; }
1434 return t->data.val = CSA_FAIL_NOADDR;
1440 /*************************************************
1441 * Handle verification (address & other) *
1442 *************************************************/
1444 /* This function implements the "verify" condition. It is called when
1445 encountered in any ACL, because some tests are almost always permitted. Some
1446 just don't make sense, and always fail (for example, an attempt to test a host
1447 lookup for a non-TCP/IP message). Others are restricted to certain ACLs.
1450 where where called from
1451 addr the recipient address that the ACL is handling, or NULL
1452 arg the argument of "verify"
1453 user_msgptr pointer for user message
1454 log_msgptr pointer for log message
1455 basic_errno where to put verify errno
1457 Returns: OK verification condition succeeded
1458 FAIL verification failed
1459 DEFER there was a problem verifying
1464 acl_verify(int where, address_item *addr, uschar *arg,
1465 uschar **user_msgptr, uschar **log_msgptr, int *basic_errno)
1469 int callout_overall = -1;
1470 int callout_connect = -1;
1471 int verify_options = 0;
1473 BOOL verify_header_sender = FALSE;
1474 BOOL defer_ok = FALSE;
1475 BOOL callout_defer_ok = FALSE;
1476 BOOL no_details = FALSE;
1477 BOOL success_on_redirect = FALSE;
1478 address_item *sender_vaddr = NULL;
1479 uschar *verify_sender_address = NULL;
1480 uschar *pm_mailfrom = NULL;
1481 uschar *se_mailfrom = NULL;
1483 /* Some of the verify items have slash-separated options; some do not. Diagnose
1484 an error if options are given for items that don't expect them. This code has
1485 now got very message. Refactoring to use a table would be a good idea one day.
1488 uschar *slash = Ustrchr(arg, '/');
1490 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
1492 if (ss == NULL) goto BAD_VERIFY;
1494 /* Handle name/address consistency verification in a separate function. */
1496 if (strcmpic(ss, US"reverse_host_lookup") == 0)
1498 if (slash != NULL) goto NO_OPTIONS;
1499 if (sender_host_address == NULL) return OK;
1500 return acl_verify_reverse(user_msgptr, log_msgptr);
1503 /* TLS certificate verification is done at STARTTLS time; here we just
1504 test whether it was successful or not. (This is for optional verification; for
1505 mandatory verification, the connection doesn't last this long.) */
1507 if (strcmpic(ss, US"certificate") == 0)
1509 if (slash != NULL) goto NO_OPTIONS;
1510 if (tls_certificate_verified) return OK;
1511 *user_msgptr = US"no verified certificate";
1515 /* We can test the result of optional HELO verification that might have
1516 occurred earlier. If not, we can attempt the verification now. */
1518 if (strcmpic(ss, US"helo") == 0)
1520 if (slash != NULL) goto NO_OPTIONS;
1521 if (!helo_verified && !helo_verify_failed) smtp_verify_helo();
1522 return helo_verified? OK : FAIL;
1525 /* Do Client SMTP Authorization checks in a separate function, and turn the
1526 result code into user-friendly strings. */
1528 if (strcmpic(ss, US"csa") == 0)
1530 rc = acl_verify_csa(list);
1531 *log_msgptr = *user_msgptr = string_sprintf("client SMTP authorization %s",
1532 csa_reason_string[rc]);
1533 csa_status = csa_status_string[rc];
1534 DEBUG(D_acl) debug_printf("CSA result %s\n", csa_status);
1535 return csa_return_code[rc];
1538 /* Check that all relevant header lines have the correct syntax. If there is
1539 a syntax error, we return details of the error to the sender if configured to
1540 send out full details. (But a "message" setting on the ACL can override, as
1543 if (strcmpic(ss, US"header_syntax") == 0)
1545 if (slash != NULL) goto NO_OPTIONS;
1546 if (where != ACL_WHERE_DATA && where != ACL_WHERE_NOTSMTP) goto WRONG_ACL;
1547 rc = verify_check_headers(log_msgptr);
1548 if (rc != OK && smtp_return_error_details && *log_msgptr != NULL)
1549 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1553 /* Check that no recipient of this message is "blind", that is, every envelope
1554 recipient must be mentioned in either To: or Cc:. */
1556 if (strcmpic(ss, US"not_blind") == 0)
1558 if (slash != NULL) goto NO_OPTIONS;
1559 if (where != ACL_WHERE_DATA && where != ACL_WHERE_NOTSMTP) goto WRONG_ACL;
1560 rc = verify_check_notblind();
1563 *log_msgptr = string_sprintf("bcc recipient detected");
1564 if (smtp_return_error_details)
1565 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1570 /* The remaining verification tests check recipient and sender addresses,
1571 either from the envelope or from the header. There are a number of
1572 slash-separated options that are common to all of them. */
1575 /* Check that there is at least one verifiable sender address in the relevant
1576 header lines. This can be followed by callout and defer options, just like
1577 sender and recipient. */
1579 if (strcmpic(ss, US"header_sender") == 0)
1581 if (where != ACL_WHERE_DATA && where != ACL_WHERE_NOTSMTP) goto WRONG_ACL;
1582 verify_header_sender = TRUE;
1585 /* Otherwise, first item in verify argument must be "sender" or "recipient".
1586 In the case of a sender, this can optionally be followed by an address to use
1587 in place of the actual sender (rare special-case requirement). */
1589 else if (strncmpic(ss, US"sender", 6) == 0)
1592 if (where > ACL_WHERE_NOTSMTP)
1594 *log_msgptr = string_sprintf("cannot verify sender in ACL for %s "
1595 "(only possible for MAIL, RCPT, PREDATA, or DATA)",
1596 acl_wherenames[where]);
1600 verify_sender_address = sender_address;
1603 while (isspace(*s)) s++;
1604 if (*s++ != '=') goto BAD_VERIFY;
1605 while (isspace(*s)) s++;
1606 verify_sender_address = string_copy(s);
1611 if (strcmpic(ss, US"recipient") != 0) goto BAD_VERIFY;
1614 *log_msgptr = string_sprintf("cannot verify recipient in ACL for %s "
1615 "(only possible for RCPT)", acl_wherenames[where]);
1620 /* Remaining items are optional; they apply to sender and recipient
1621 verification, including "header sender" verification. */
1623 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size))
1626 if (strcmpic(ss, US"defer_ok") == 0) defer_ok = TRUE;
1627 else if (strcmpic(ss, US"no_details") == 0) no_details = TRUE;
1628 else if (strcmpic(ss, US"success_on_redirect") == 0) success_on_redirect = TRUE;
1630 /* These two old options are left for backwards compatibility */
1632 else if (strcmpic(ss, US"callout_defer_ok") == 0)
1634 callout_defer_ok = TRUE;
1635 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1638 else if (strcmpic(ss, US"check_postmaster") == 0)
1641 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1644 /* The callout option has a number of sub-options, comma separated */
1646 else if (strncmpic(ss, US"callout", 7) == 0)
1648 callout = CALLOUT_TIMEOUT_DEFAULT;
1652 while (isspace(*ss)) ss++;
1658 while (isspace(*ss)) ss++;
1660 /* This callout option handling code has become a mess as new options
1661 have been added in an ad hoc manner. It should be tidied up into some
1662 kind of table-driven thing. */
1664 while ((opt = string_nextinlist(&ss, &optsep, buffer, sizeof(buffer)))
1667 if (strcmpic(opt, US"defer_ok") == 0) callout_defer_ok = TRUE;
1668 else if (strcmpic(opt, US"no_cache") == 0)
1669 verify_options |= vopt_callout_no_cache;
1670 else if (strcmpic(opt, US"random") == 0)
1671 verify_options |= vopt_callout_random;
1672 else if (strcmpic(opt, US"use_sender") == 0)
1673 verify_options |= vopt_callout_recipsender;
1674 else if (strcmpic(opt, US"use_postmaster") == 0)
1675 verify_options |= vopt_callout_recippmaster;
1676 else if (strcmpic(opt, US"postmaster") == 0) pm_mailfrom = US"";
1677 else if (strcmpic(opt, US"fullpostmaster") == 0)
1680 verify_options |= vopt_callout_fullpm;
1683 else if (strncmpic(opt, US"mailfrom", 8) == 0)
1685 if (!verify_header_sender)
1687 *log_msgptr = string_sprintf("\"mailfrom\" is allowed as a "
1688 "callout option only for verify=header_sender (detected in ACL "
1689 "condition \"%s\")", arg);
1693 while (isspace(*opt)) opt++;
1696 *log_msgptr = string_sprintf("'=' expected after "
1697 "\"mailfrom\" in ACL condition \"%s\"", arg);
1700 while (isspace(*opt)) opt++;
1701 se_mailfrom = string_copy(opt);
1704 else if (strncmpic(opt, US"postmaster_mailfrom", 19) == 0)
1707 while (isspace(*opt)) opt++;
1710 *log_msgptr = string_sprintf("'=' expected after "
1711 "\"postmaster_mailfrom\" in ACL condition \"%s\"", arg);
1714 while (isspace(*opt)) opt++;
1715 pm_mailfrom = string_copy(opt);
1718 else if (strncmpic(opt, US"maxwait", 7) == 0)
1721 while (isspace(*opt)) opt++;
1724 *log_msgptr = string_sprintf("'=' expected after \"maxwait\" in "
1725 "ACL condition \"%s\"", arg);
1728 while (isspace(*opt)) opt++;
1729 callout_overall = readconf_readtime(opt, 0, FALSE);
1730 if (callout_overall < 0)
1732 *log_msgptr = string_sprintf("bad time value in ACL condition "
1733 "\"verify %s\"", arg);
1737 else if (strncmpic(opt, US"connect", 7) == 0)
1740 while (isspace(*opt)) opt++;
1743 *log_msgptr = string_sprintf("'=' expected after "
1744 "\"callout_overaall\" in ACL condition \"%s\"", arg);
1747 while (isspace(*opt)) opt++;
1748 callout_connect = readconf_readtime(opt, 0, FALSE);
1749 if (callout_connect < 0)
1751 *log_msgptr = string_sprintf("bad time value in ACL condition "
1752 "\"verify %s\"", arg);
1756 else /* Plain time is callout connect/command timeout */
1758 callout = readconf_readtime(opt, 0, FALSE);
1761 *log_msgptr = string_sprintf("bad time value in ACL condition "
1762 "\"verify %s\"", arg);
1770 *log_msgptr = string_sprintf("'=' expected after \"callout\" in "
1771 "ACL condition \"%s\"", arg);
1777 /* Option not recognized */
1781 *log_msgptr = string_sprintf("unknown option \"%s\" in ACL "
1782 "condition \"verify %s\"", ss, arg);
1787 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster)) ==
1788 (vopt_callout_recipsender|vopt_callout_recippmaster))
1790 *log_msgptr = US"only one of use_sender and use_postmaster can be set "
1791 "for a recipient callout";
1795 /* Handle sender-in-header verification. Default the user message to the log
1796 message if giving out verification details. */
1798 if (verify_header_sender)
1801 rc = verify_check_header_address(user_msgptr, log_msgptr, callout,
1802 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, verify_options,
1806 *basic_errno = verrno;
1807 if (smtp_return_error_details)
1809 if (*user_msgptr == NULL && *log_msgptr != NULL)
1810 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1811 if (rc == DEFER) acl_temp_details = TRUE;
1816 /* Handle a sender address. The default is to verify *the* sender address, but
1817 optionally a different address can be given, for special requirements. If the
1818 address is empty, we are dealing with a bounce message that has no sender, so
1819 we cannot do any checking. If the real sender address gets rewritten during
1820 verification (e.g. DNS widening), set the flag to stop it being rewritten again
1821 during message reception.
1823 A list of verified "sender" addresses is kept to try to avoid doing to much
1824 work repetitively when there are multiple recipients in a message and they all
1825 require sender verification. However, when callouts are involved, it gets too
1826 complicated because different recipients may require different callout options.
1827 Therefore, we always do a full sender verify when any kind of callout is
1828 specified. Caching elsewhere, for instance in the DNS resolver and in the
1829 callout handling, should ensure that this is not terribly inefficient. */
1831 else if (verify_sender_address != NULL)
1833 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster))
1836 *log_msgptr = US"use_sender or use_postmaster cannot be used for a "
1837 "sender verify callout";
1841 sender_vaddr = verify_checked_sender(verify_sender_address);
1842 if (sender_vaddr != NULL && /* Previously checked */
1843 callout <= 0) /* No callout needed this time */
1845 /* If the "routed" flag is set, it means that routing worked before, so
1846 this check can give OK (the saved return code value, if set, belongs to a
1847 callout that was done previously). If the "routed" flag is not set, routing
1848 must have failed, so we use the saved return code. */
1850 if (testflag(sender_vaddr, af_verify_routed)) rc = OK; else
1852 rc = sender_vaddr->special_action;
1853 *basic_errno = sender_vaddr->basic_errno;
1855 HDEBUG(D_acl) debug_printf("using cached sender verify result\n");
1858 /* Do a new verification, and cache the result. The cache is used to avoid
1859 verifying the sender multiple times for multiple RCPTs when callouts are not
1860 specified (see comments above).
1862 The cache is also used on failure to give details in response to the first
1863 RCPT that gets bounced for this reason. However, this can be suppressed by
1864 the no_details option, which sets the flag that says "this detail has already
1865 been sent". The cache normally contains just one address, but there may be
1866 more in esoteric circumstances. */
1871 uschar *save_address_data = deliver_address_data;
1873 sender_vaddr = deliver_make_addr(verify_sender_address, TRUE);
1874 if (no_details) setflag(sender_vaddr, af_sverify_told);
1875 if (verify_sender_address[0] != 0)
1877 /* If this is the real sender address, save the unrewritten version
1878 for use later in receive. Otherwise, set a flag so that rewriting the
1879 sender in verify_address() does not update sender_address. */
1881 if (verify_sender_address == sender_address)
1882 sender_address_unrewritten = sender_address;
1884 verify_options |= vopt_fake_sender;
1886 if (success_on_redirect)
1887 verify_options |= vopt_success_on_redirect;
1889 /* The recipient, qualify, and expn options are never set in
1892 rc = verify_address(sender_vaddr, NULL, verify_options, callout,
1893 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, &routed);
1895 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
1899 if (Ustrcmp(sender_vaddr->address, verify_sender_address) != 0)
1901 DEBUG(D_acl) debug_printf("sender %s verified ok as %s\n",
1902 verify_sender_address, sender_vaddr->address);
1906 DEBUG(D_acl) debug_printf("sender %s verified ok\n",
1907 verify_sender_address);
1910 else *basic_errno = sender_vaddr->basic_errno;
1912 else rc = OK; /* Null sender */
1914 /* Cache the result code */
1916 if (routed) setflag(sender_vaddr, af_verify_routed);
1917 if (callout > 0) setflag(sender_vaddr, af_verify_callout);
1918 sender_vaddr->special_action = rc;
1919 sender_vaddr->next = sender_verified_list;
1920 sender_verified_list = sender_vaddr;
1922 /* Restore the recipient address data, which might have been clobbered by
1923 the sender verification. */
1925 deliver_address_data = save_address_data;
1928 /* Put the sender address_data value into $sender_address_data */
1930 sender_address_data = sender_vaddr->p.address_data;
1933 /* A recipient address just gets a straightforward verify; again we must handle
1934 the DEFER overrides. */
1940 if (success_on_redirect)
1941 verify_options |= vopt_success_on_redirect;
1943 /* We must use a copy of the address for verification, because it might
1947 rc = verify_address(&addr2, NULL, verify_options|vopt_is_recipient, callout,
1948 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, NULL);
1949 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
1951 *basic_errno = addr2.basic_errno;
1952 *log_msgptr = addr2.message;
1953 *user_msgptr = (addr2.user_message != NULL)?
1954 addr2.user_message : addr2.message;
1956 /* Allow details for temporary error if the address is so flagged. */
1957 if (testflag((&addr2), af_pass_message)) acl_temp_details = TRUE;
1959 /* Make $address_data visible */
1960 deliver_address_data = addr2.p.address_data;
1963 /* We have a result from the relevant test. Handle defer overrides first. */
1965 if (rc == DEFER && (defer_ok ||
1966 (callout_defer_ok && *basic_errno == ERRNO_CALLOUTDEFER)))
1968 HDEBUG(D_acl) debug_printf("verify defer overridden by %s\n",
1969 defer_ok? "defer_ok" : "callout_defer_ok");
1973 /* If we've failed a sender, set up a recipient message, and point
1974 sender_verified_failed to the address item that actually failed. */
1976 if (rc != OK && verify_sender_address != NULL)
1980 *log_msgptr = *user_msgptr = US"Sender verify failed";
1982 else if (*basic_errno != ERRNO_CALLOUTDEFER)
1984 *log_msgptr = *user_msgptr = US"Could not complete sender verify";
1988 *log_msgptr = US"Could not complete sender verify callout";
1989 *user_msgptr = smtp_return_error_details? sender_vaddr->user_message :
1993 sender_verified_failed = sender_vaddr;
1996 /* Verifying an address messes up the values of $domain and $local_part,
1997 so reset them before returning if this is a RCPT ACL. */
2001 deliver_domain = addr->domain;
2002 deliver_localpart = addr->local_part;
2006 /* Syntax errors in the verify argument come here. */
2009 *log_msgptr = string_sprintf("expected \"sender[=address]\", \"recipient\", "
2010 "\"helo\", \"header_syntax\", \"header_sender\" or "
2011 "\"reverse_host_lookup\" at start of ACL condition "
2012 "\"verify %s\"", arg);
2015 /* Options supplied when not allowed come here */
2018 *log_msgptr = string_sprintf("unexpected '/' found in \"%s\" "
2019 "(this verify item has no options)", arg);
2022 /* Calls in the wrong ACL come here */
2025 *log_msgptr = string_sprintf("cannot check header contents in ACL for %s "
2026 "(only possible in ACL for DATA)", acl_wherenames[where]);
2033 /*************************************************
2034 * Check argument for control= modifier *
2035 *************************************************/
2037 /* Called from acl_check_condition() below
2040 arg the argument string for control=
2041 pptr set to point to the terminating character
2042 where which ACL we are in
2043 log_msgptr for error messages
2045 Returns: CONTROL_xxx value
2049 decode_control(uschar *arg, uschar **pptr, int where, uschar **log_msgptr)
2054 for (d = controls_list;
2055 d < controls_list + sizeof(controls_list)/sizeof(control_def);
2058 len = Ustrlen(d->name);
2059 if (Ustrncmp(d->name, arg, len) == 0) break;
2062 if (d >= controls_list + sizeof(controls_list)/sizeof(control_def) ||
2063 (arg[len] != 0 && (!d->has_option || arg[len] != '/')))
2065 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
2066 return CONTROL_ERROR;
2075 /*************************************************
2076 * Handle rate limiting *
2077 *************************************************/
2079 /* Called by acl_check_condition() below to calculate the result
2080 of the ACL ratelimit condition.
2082 Note that the return value might be slightly unexpected: if the
2083 sender's rate is above the limit then the result is OK. This is
2084 similar to the dnslists condition, and is so that you can write
2085 ACL clauses like: defer ratelimit = 15 / 1h
2088 arg the option string for ratelimit=
2089 where ACL_WHERE_xxxx indicating which ACL this is
2090 log_msgptr for error messages
2092 Returns: OK - Sender's rate is above limit
2093 FAIL - Sender's rate is below limit
2094 DEFER - Problem opening ratelimit database
2095 ERROR - Syntax error in options.
2099 acl_ratelimit(uschar *arg, int where, uschar **log_msgptr)
2101 double limit, period;
2105 BOOL leaky = FALSE, strict = FALSE, noupdate = FALSE;
2106 BOOL per_byte = FALSE, per_cmd = FALSE, per_conn = FALSE, per_mail = FALSE;
2108 tree_node **anchor, *t;
2109 open_db dbblock, *dbm;
2110 dbdata_ratelimit *dbd;
2113 /* Parse the first two options and record their values in expansion
2114 variables. These variables allow the configuration to have informative
2115 error messages based on rate limits obtained from a table lookup. */
2117 /* First is the maximum number of messages per period and maximum burst
2118 size, which must be greater than or equal to zero. Zero is useful for
2119 rate measurement as opposed to rate limiting. */
2121 sender_rate_limit = string_nextinlist(&arg, &sep, NULL, 0);
2122 if (sender_rate_limit == NULL)
2126 limit = Ustrtod(sender_rate_limit, &ss);
2127 if (tolower(*ss) == 'k') { limit *= 1024.0; ss++; }
2128 else if (tolower(*ss) == 'm') { limit *= 1024.0*1024.0; ss++; }
2129 else if (tolower(*ss) == 'g') { limit *= 1024.0*1024.0*1024.0; ss++; }
2131 if (limit < 0.0 || *ss != 0)
2133 *log_msgptr = string_sprintf("syntax error in argument for "
2134 "\"ratelimit\" condition: \"%s\" is not a positive number",
2139 /* Second is the rate measurement period and exponential smoothing time
2140 constant. This must be strictly greater than zero, because zero leads to
2141 run-time division errors. */
2143 sender_rate_period = string_nextinlist(&arg, &sep, NULL, 0);
2144 if (sender_rate_period == NULL) period = -1.0;
2145 else period = readconf_readtime(sender_rate_period, 0, FALSE);
2148 *log_msgptr = string_sprintf("syntax error in argument for "
2149 "\"ratelimit\" condition: \"%s\" is not a time value",
2150 sender_rate_period);
2154 /* Parse the other options. Should we check if the per_* options are being
2155 used in ACLs where they don't make sense, e.g. per_mail in the connect ACL? */
2157 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2160 if (strcmpic(ss, US"leaky") == 0) leaky = TRUE;
2161 else if (strcmpic(ss, US"strict") == 0) strict = TRUE;
2162 else if (strcmpic(ss, US"noupdate") == 0) noupdate = TRUE;
2163 else if (strcmpic(ss, US"per_byte") == 0) per_byte = TRUE;
2164 else if (strcmpic(ss, US"per_cmd") == 0) per_cmd = TRUE;
2165 else if (strcmpic(ss, US"per_rcpt") == 0) per_cmd = TRUE; /* alias */
2166 else if (strcmpic(ss, US"per_conn") == 0) per_conn = TRUE;
2167 else if (strcmpic(ss, US"per_mail") == 0) per_mail = TRUE;
2168 else key = string_sprintf("%s", ss);
2171 if (leaky + strict > 1 || per_byte + per_cmd + per_conn + per_mail > 1)
2173 *log_msgptr = US"conflicting options for \"ratelimit\" condition";
2177 /* Default option values */
2179 if (!strict) leaky = TRUE;
2180 if (!per_byte && !per_cmd && !per_conn) per_mail = TRUE;
2182 /* Create the lookup key. If there is no explicit key, use sender_host_address.
2183 If there is no sender_host_address (e.g. -bs or acl_not_smtp) then we simply
2184 omit it. The smoothing constant (sender_rate_period) and the per_xxx options
2185 are added to the key because they alter the meaning of the stored data. */
2188 key = (sender_host_address == NULL)? US"" : sender_host_address;
2190 key = string_sprintf("%s/%s/%s/%s",
2192 per_byte? US"per_byte" :
2193 per_cmd? US"per_cmd" :
2194 per_mail? US"per_mail" : US"per_conn",
2195 strict? US"strict" : US"leaky",
2198 HDEBUG(D_acl) debug_printf("ratelimit condition limit=%.0f period=%.0f key=%s\n",
2199 limit, period, key);
2201 /* See if we have already computed the rate by looking in the relevant tree.
2202 For per-connection rate limiting, store tree nodes and dbdata in the permanent
2203 pool so that they survive across resets. */
2206 old_pool = store_pool;
2210 anchor = &ratelimiters_conn;
2211 store_pool = POOL_PERM;
2213 else if (per_mail || per_byte)
2214 anchor = &ratelimiters_mail;
2216 anchor = &ratelimiters_cmd;
2218 if (anchor != NULL && (t = tree_search(*anchor, key)) != NULL)
2221 /* The following few lines duplicate some of the code below. */
2222 rc = (dbd->rate < limit)? FAIL : OK;
2223 store_pool = old_pool;
2224 sender_rate = string_sprintf("%.1f", dbd->rate);
2226 debug_printf("ratelimit found pre-computed rate %s\n", sender_rate);
2230 /* We aren't using a pre-computed rate, so get a previously recorded
2231 rate from the database, update it, and write it back when required. If there's
2232 no previous rate for this key, create one. */
2234 dbm = dbfn_open(US"ratelimit", O_RDWR, &dbblock, TRUE);
2237 store_pool = old_pool;
2239 HDEBUG(D_acl) debug_printf("ratelimit database not available\n");
2240 *log_msgptr = US"ratelimit database not available";
2243 dbd = dbfn_read(dbm, key);
2245 gettimeofday(&tv, NULL);
2249 HDEBUG(D_acl) debug_printf("ratelimit initializing new key's data\n");
2250 dbd = store_get(sizeof(dbdata_ratelimit));
2251 dbd->time_stamp = tv.tv_sec;
2252 dbd->time_usec = tv.tv_usec;
2257 /* The smoothed rate is computed using an exponentially weighted moving
2258 average adjusted for variable sampling intervals. The standard EWMA for
2259 a fixed sampling interval is: f'(t) = (1 - a) * f(t) + a * f'(t - 1)
2260 where f() is the measured value and f'() is the smoothed value.
2262 Old data decays out of the smoothed value exponentially, such that data n
2263 samples old is multiplied by a^n. The exponential decay time constant p
2264 is defined such that data p samples old is multiplied by 1/e, which means
2265 that a = exp(-1/p). We can maintain the same time constant for a variable
2266 sampling interval i by using a = exp(-i/p).
2268 The rate we are measuring is messages per period, suitable for directly
2269 comparing with the limit. The average rate between now and the previous
2270 message is period / interval, which we feed into the EWMA as the sample.
2272 It turns out that the number of messages required for the smoothed rate
2273 to reach the limit when they are sent in a burst is equal to the limit.
2274 This can be seen by analysing the value of the smoothed rate after N
2275 messages sent at even intervals. Let k = (1 - a) * p/i
2277 rate_1 = (1 - a) * p/i + a * rate_0
2279 rate_2 = k + a * rate_1
2280 = k + a * k + a^2 * rate_0
2281 rate_3 = k + a * k + a^2 * k + a^3 * rate_0
2282 rate_N = rate_0 * a^N + k * SUM(x=0..N-1)(a^x)
2283 = rate_0 * a^N + k * (1 - a^N) / (1 - a)
2284 = rate_0 * a^N + p/i * (1 - a^N)
2286 When N is large, a^N -> 0 so rate_N -> p/i as desired.
2288 rate_N = p/i + (rate_0 - p/i) * a^N
2289 a^N = (rate_N - p/i) / (rate_0 - p/i)
2290 N * -i/p = log((rate_N - p/i) / (rate_0 - p/i))
2291 N = p/i * log((rate_0 - p/i) / (rate_N - p/i))
2293 Numerical analysis of the above equation, setting the computed rate to
2294 increase from rate_0 = 0 to rate_N = limit, shows that for large sending
2295 rates, p/i, the number of messages N = limit. So limit serves as both the
2296 maximum rate measured in messages per period, and the maximum number of
2297 messages that can be sent in a fast burst. */
2299 double this_time = (double)tv.tv_sec
2300 + (double)tv.tv_usec / 1000000.0;
2301 double prev_time = (double)dbd->time_stamp
2302 + (double)dbd->time_usec / 1000000.0;
2304 /* We must avoid division by zero, and deal gracefully with the clock going
2305 backwards. If we blunder ahead when time is in reverse then the computed
2306 rate will be bogus. To be safe we clamp interval to a very small number. */
2308 double interval = this_time - prev_time <= 0.0 ? 1e-9
2309 : this_time - prev_time;
2311 double i_over_p = interval / period;
2312 double a = exp(-i_over_p);
2314 dbd->time_stamp = tv.tv_sec;
2315 dbd->time_usec = tv.tv_usec;
2317 /* If we are measuring the rate in bytes per period, multiply the
2318 measured rate by the message size. If we don't know the message size
2319 then it's safe to just use a value of zero and let the recorded rate
2320 decay as if nothing happened. */
2323 dbd->rate = (message_size < 0 ? 0.0 : (double)message_size)
2324 * (1 - a) / i_over_p + a * dbd->rate;
2325 else if (per_cmd && where == ACL_WHERE_NOTSMTP)
2326 dbd->rate = (double)recipients_count
2327 * (1 - a) / i_over_p + a * dbd->rate;
2329 dbd->rate = (1 - a) / i_over_p + a * dbd->rate;
2332 /* Clients sending at the limit are considered to be over the limit. This
2333 matters for edge cases such the first message sent by a client (which gets
2334 the initial rate of 0.0) when the rate limit is zero (i.e. the client should
2335 be completely blocked). */
2337 rc = (dbd->rate < limit)? FAIL : OK;
2339 /* Update the state if the rate is low or if we are being strict. If we
2340 are in leaky mode and the sender's rate is too high, we do not update
2341 the recorded rate in order to avoid an over-aggressive sender's retry
2342 rate preventing them from getting any email through. If noupdate is set,
2343 do not do any updates. */
2345 if ((rc == FAIL || !leaky) && !noupdate)
2347 dbfn_write(dbm, key, dbd, sizeof(dbdata_ratelimit));
2348 HDEBUG(D_acl) debug_printf("ratelimit db updated\n");
2352 HDEBUG(D_acl) debug_printf("ratelimit db not updated: %s\n",
2353 noupdate? "noupdate set" : "over the limit, but leaky");
2358 /* Store the result in the tree for future reference, if necessary. */
2360 if (anchor != NULL && !noupdate)
2362 t = store_get(sizeof(tree_node) + Ustrlen(key));
2364 Ustrcpy(t->name, key);
2365 (void)tree_insertnode(anchor, t);
2368 /* We create the formatted version of the sender's rate very late in
2369 order to ensure that it is done using the correct storage pool. */
2371 store_pool = old_pool;
2372 sender_rate = string_sprintf("%.1f", dbd->rate);
2375 debug_printf("ratelimit computed rate %s\n", sender_rate);
2382 /*************************************************
2383 * Handle conditions/modifiers on an ACL item *
2384 *************************************************/
2386 /* Called from acl_check() below.
2390 cb ACL condition block - if NULL, result is OK
2391 where where called from
2392 addr the address being checked for RCPT, or NULL
2393 level the nesting level
2394 epp pointer to pass back TRUE if "endpass" encountered
2395 (applies only to "accept" and "discard")
2396 user_msgptr user message pointer
2397 log_msgptr log message pointer
2398 basic_errno pointer to where to put verify error
2400 Returns: OK - all conditions are met
2401 DISCARD - an "acl" condition returned DISCARD - only allowed
2402 for "accept" or "discard" verbs
2403 FAIL - at least one condition fails
2404 FAIL_DROP - an "acl" condition returned FAIL_DROP
2405 DEFER - can't tell at the moment (typically, lookup defer,
2406 but can be temporary callout problem)
2407 ERROR - ERROR from nested ACL or expansion failure or other
2412 acl_check_condition(int verb, acl_condition_block *cb, int where,
2413 address_item *addr, int level, BOOL *epp, uschar **user_msgptr,
2414 uschar **log_msgptr, int *basic_errno)
2416 uschar *user_message = NULL;
2417 uschar *log_message = NULL;
2420 #ifdef WITH_CONTENT_SCAN
2424 for (; cb != NULL; cb = cb->next)
2429 /* The message and log_message items set up messages to be used in
2430 case of rejection. They are expanded later. */
2432 if (cb->type == ACLC_MESSAGE)
2434 user_message = cb->arg;
2438 if (cb->type == ACLC_LOG_MESSAGE)
2440 log_message = cb->arg;
2444 /* The endpass "condition" just sets a flag to show it occurred. This is
2445 checked at compile time to be on an "accept" or "discard" item. */
2447 if (cb->type == ACLC_ENDPASS)
2453 /* For other conditions and modifiers, the argument is expanded now for some
2454 of them, but not for all, because expansion happens down in some lower level
2455 checking functions in some cases. */
2457 if (cond_expand_at_top[cb->type])
2459 arg = expand_string(cb->arg);
2462 if (expand_string_forcedfail) continue;
2463 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s",
2464 cb->arg, expand_string_message);
2465 return search_find_defer? DEFER : ERROR;
2470 /* Show condition, and expanded condition if it's different */
2475 debug_printf("check %s%s %n",
2476 (!cond_modifiers[cb->type] && cb->u.negated)? "!":"",
2477 conditions[cb->type], &lhswidth);
2479 if (cb->type == ACLC_SET)
2481 debug_printf("acl_%s ", cb->u.varname);
2482 lhswidth += 5 + Ustrlen(cb->u.varname);
2485 debug_printf("= %s\n", cb->arg);
2488 debug_printf("%.*s= %s\n", lhswidth,
2492 /* Check that this condition makes sense at this time */
2494 if ((cond_forbids[cb->type] & (1 << where)) != 0)
2496 *log_msgptr = string_sprintf("cannot %s %s condition in %s ACL",
2497 cond_modifiers[cb->type]? "use" : "test",
2498 conditions[cb->type], acl_wherenames[where]);
2502 /* Run the appropriate test for each condition, or take the appropriate
2503 action for the remaining modifiers. */
2507 case ACLC_ADD_HEADER:
2511 /* A nested ACL that returns "discard" makes sense only for an "accept" or
2515 rc = acl_check_internal(where, addr, arg, level+1, user_msgptr, log_msgptr);
2516 if (rc == DISCARD && verb != ACL_ACCEPT && verb != ACL_DISCARD)
2518 *log_msgptr = string_sprintf("nested ACL returned \"discard\" for "
2519 "\"%s\" command (only allowed with \"accept\" or \"discard\")",
2525 case ACLC_AUTHENTICATED:
2526 rc = (sender_host_authenticated == NULL)? FAIL :
2527 match_isinlist(sender_host_authenticated, &arg, 0, NULL, NULL, MCL_STRING,
2531 #ifdef EXPERIMENTAL_BRIGHTMAIL
2532 case ACLC_BMI_OPTIN:
2534 int old_pool = store_pool;
2535 store_pool = POOL_PERM;
2536 bmi_current_optin = string_copy(arg);
2537 store_pool = old_pool;
2542 case ACLC_CONDITION:
2543 if (Ustrspn(arg, "0123456789") == Ustrlen(arg)) /* Digits, or empty */
2544 rc = (Uatoi(arg) == 0)? FAIL : OK;
2546 rc = (strcmpic(arg, US"no") == 0 ||
2547 strcmpic(arg, US"false") == 0)? FAIL :
2548 (strcmpic(arg, US"yes") == 0 ||
2549 strcmpic(arg, US"true") == 0)? OK : DEFER;
2551 *log_msgptr = string_sprintf("invalid \"condition\" value \"%s\"", arg);
2554 case ACLC_CONTINUE: /* Always succeeds */
2558 control_type = decode_control(arg, &p, where, log_msgptr);
2560 /* Check if this control makes sense at this time */
2562 if ((control_forbids[control_type] & (1 << where)) != 0)
2564 *log_msgptr = string_sprintf("cannot use \"control=%s\" in %s ACL",
2565 controls[control_type], acl_wherenames[where]);
2569 switch(control_type)
2571 case CONTROL_AUTH_UNADVERTISED:
2572 allow_auth_unadvertised = TRUE;
2575 #ifdef EXPERIMENTAL_BRIGHTMAIL
2576 case CONTROL_BMI_RUN:
2581 #ifndef DISABLE_DKIM
2582 case CONTROL_DKIM_VERIFY:
2583 dkim_disable_verify = TRUE;
2590 case CONTROL_CASEFUL_LOCAL_PART:
2591 deliver_localpart = addr->cc_local_part;
2594 case CONTROL_CASELOWER_LOCAL_PART:
2595 deliver_localpart = addr->lc_local_part;
2598 case CONTROL_ENFORCE_SYNC:
2599 smtp_enforce_sync = TRUE;
2602 case CONTROL_NO_ENFORCE_SYNC:
2603 smtp_enforce_sync = FALSE;
2606 #ifdef WITH_CONTENT_SCAN
2607 case CONTROL_NO_MBOX_UNSPOOL:
2608 no_mbox_unspool = TRUE;
2612 case CONTROL_NO_MULTILINE:
2613 no_multiline_responses = TRUE;
2616 case CONTROL_NO_PIPELINING:
2617 pipelining_enable = FALSE;
2620 case CONTROL_NO_DELAY_FLUSH:
2621 disable_delay_flush = TRUE;
2624 case CONTROL_NO_CALLOUT_FLUSH:
2625 disable_callout_flush = TRUE;
2628 case CONTROL_FAKEDEFER:
2629 case CONTROL_FAKEREJECT:
2630 fake_response = (control_type == CONTROL_FAKEDEFER) ? DEFER : FAIL;
2634 while (*pp != 0) pp++;
2635 fake_response_text = expand_string(string_copyn(p+1, pp-p-1));
2640 /* Explicitly reset to default string */
2641 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).";
2645 case CONTROL_FREEZE:
2646 deliver_freeze = TRUE;
2647 deliver_frozen_at = time(NULL);
2648 freeze_tell = freeze_tell_config; /* Reset to configured value */
2649 if (Ustrncmp(p, "/no_tell", 8) == 0)
2656 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
2661 case CONTROL_QUEUE_ONLY:
2662 queue_only_policy = TRUE;
2665 case CONTROL_SUBMISSION:
2666 originator_name = US"";
2667 submission_mode = TRUE;
2670 if (Ustrncmp(p, "/sender_retain", 14) == 0)
2673 active_local_sender_retain = TRUE;
2674 active_local_from_check = FALSE;
2676 else if (Ustrncmp(p, "/domain=", 8) == 0)
2679 while (*pp != 0 && *pp != '/') pp++;
2680 submission_domain = string_copyn(p+8, pp-p-8);
2683 /* The name= option must be last, because it swallows the rest of
2685 else if (Ustrncmp(p, "/name=", 6) == 0)
2688 while (*pp != 0) pp++;
2689 submission_name = string_copy(parse_fix_phrase(p+6, pp-p-6,
2690 big_buffer, big_buffer_size));
2697 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
2702 case CONTROL_SUPPRESS_LOCAL_FIXUPS:
2703 suppress_local_fixups = TRUE;
2708 #ifdef EXPERIMENTAL_DCC
2711 /* Seperate the regular expression and any optional parameters. */
2712 uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size);
2713 /* Run the dcc backend. */
2714 rc = dcc_process(&ss);
2715 /* Modify return code based upon the existance of options. */
2716 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2718 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
2720 /* FAIL so that the message is passed to the next ACL */
2728 #ifdef WITH_CONTENT_SCAN
2730 rc = mime_decode(&arg);
2736 int delay = readconf_readtime(arg, 0, FALSE);
2739 *log_msgptr = string_sprintf("syntax error in argument for \"delay\" "
2740 "modifier: \"%s\" is not a time value", arg);
2745 HDEBUG(D_acl) debug_printf("delay modifier requests %d-second delay\n",
2750 debug_printf("delay skipped in -bh checking mode\n");
2753 /* It appears to be impossible to detect that a TCP/IP connection has
2754 gone away without reading from it. This means that we cannot shorten
2755 the delay below if the client goes away, because we cannot discover
2756 that the client has closed its end of the connection. (The connection
2757 is actually in a half-closed state, waiting for the server to close its
2758 end.) It would be nice to be able to detect this state, so that the
2759 Exim process is not held up unnecessarily. However, it seems that we
2760 can't. The poll() function does not do the right thing, and in any case
2761 it is not always available.
2763 NOTE 1: If ever this state of affairs changes, remember that we may be
2764 dealing with stdin/stdout here, in addition to TCP/IP connections.
2765 Also, delays may be specified for non-SMTP input, where smtp_out and
2766 smtp_in will be NULL. Whatever is done must work in all cases.
2768 NOTE 2: The added feature of flushing the output before a delay must
2769 apply only to SMTP input. Hence the test for smtp_out being non-NULL.
2774 if (smtp_out != NULL && !disable_delay_flush) mac_smtp_fflush();
2775 while (delay > 0) delay = sleep(delay);
2781 #ifdef WITH_OLD_DEMIME
2787 #ifndef DISABLE_DKIM
2788 case ACLC_DKIM_SIGNER:
2789 if (dkim_signing_domain != NULL)
2791 rc = match_isinlist(dkim_signing_domain,
2792 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
2795 rc = match_isinlist(dkim_exim_expand_query(DKIM_IDENTITY),
2796 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
2805 case ACLC_DKIM_STATUS:
2806 rc = match_isinlist(dkim_exim_expand_query(DKIM_VERIFY_STATUS),
2807 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
2812 rc = verify_check_dnsbl(&arg);
2816 rc = match_isinlist(addr->domain, &arg, 0, &domainlist_anchor,
2817 addr->domain_cache, MCL_DOMAIN, TRUE, &deliver_domain_data);
2820 /* The value in tls_cipher is the full cipher name, for example,
2821 TLSv1:DES-CBC3-SHA:168, whereas the values to test for are just the
2822 cipher names such as DES-CBC3-SHA. But program defensively. We don't know
2823 what may in practice come out of the SSL library - which at the time of
2824 writing is poorly documented. */
2826 case ACLC_ENCRYPTED:
2827 if (tls_cipher == NULL) rc = FAIL; else
2829 uschar *endcipher = NULL;
2830 uschar *cipher = Ustrchr(tls_cipher, ':');
2831 if (cipher == NULL) cipher = tls_cipher; else
2833 endcipher = Ustrchr(++cipher, ':');
2834 if (endcipher != NULL) *endcipher = 0;
2836 rc = match_isinlist(cipher, &arg, 0, NULL, NULL, MCL_STRING, TRUE, NULL);
2837 if (endcipher != NULL) *endcipher = ':';
2841 /* Use verify_check_this_host() instead of verify_check_host() so that
2842 we can pass over &host_data to catch any looked up data. Once it has been
2843 set, it retains its value so that it's still there if another ACL verb
2844 comes through here and uses the cache. However, we must put it into
2845 permanent store in case it is also expected to be used in a subsequent
2846 message in the same SMTP connection. */
2849 rc = verify_check_this_host(&arg, sender_host_cache, NULL,
2850 (sender_host_address == NULL)? US"" : sender_host_address, &host_data);
2851 if (host_data != NULL) host_data = string_copy_malloc(host_data);
2854 case ACLC_LOCAL_PARTS:
2855 rc = match_isinlist(addr->cc_local_part, &arg, 0,
2856 &localpartlist_anchor, addr->localpart_cache, MCL_LOCALPART, TRUE,
2857 &deliver_localpart_data);
2860 case ACLC_LOG_REJECT_TARGET:
2866 while ((ss = string_nextinlist(&s, &sep, big_buffer, big_buffer_size))
2869 if (Ustrcmp(ss, "main") == 0) logbits |= LOG_MAIN;
2870 else if (Ustrcmp(ss, "panic") == 0) logbits |= LOG_PANIC;
2871 else if (Ustrcmp(ss, "reject") == 0) logbits |= LOG_REJECT;
2874 logbits |= LOG_MAIN|LOG_REJECT;
2875 log_write(0, LOG_MAIN|LOG_PANIC, "unknown log name \"%s\" in "
2876 "\"log_reject_target\" in %s ACL", ss, acl_wherenames[where]);
2879 log_reject_target = logbits;
2892 if (Ustrncmp(s, "main", 4) == 0)
2893 { logbits |= LOG_MAIN; s += 4; }
2894 else if (Ustrncmp(s, "panic", 5) == 0)
2895 { logbits |= LOG_PANIC; s += 5; }
2896 else if (Ustrncmp(s, "reject", 6) == 0)
2897 { logbits |= LOG_REJECT; s += 6; }
2900 logbits = LOG_MAIN|LOG_PANIC;
2901 s = string_sprintf(":unknown log name in \"%s\" in "
2902 "\"logwrite\" in %s ACL", arg, acl_wherenames[where]);
2908 while (isspace(*s)) s++;
2911 if (logbits == 0) logbits = LOG_MAIN;
2912 log_write(0, logbits, "%s", string_printing(s));
2916 #ifdef WITH_CONTENT_SCAN
2919 /* Separate the regular expression and any optional parameters. */
2920 uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size);
2921 /* Run the malware backend. */
2923 /* Modify return code based upon the existance of options. */
2924 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2926 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
2928 /* FAIL so that the message is passed to the next ACL */
2935 case ACLC_MIME_REGEX:
2936 rc = mime_regex(&arg);
2940 case ACLC_RATELIMIT:
2941 rc = acl_ratelimit(arg, where, log_msgptr);
2944 case ACLC_RECIPIENTS:
2945 rc = match_address_list(addr->address, TRUE, TRUE, &arg, NULL, -1, 0,
2949 #ifdef WITH_CONTENT_SCAN
2955 case ACLC_SENDER_DOMAINS:
2958 sdomain = Ustrrchr(sender_address, '@');
2959 sdomain = (sdomain == NULL)? US"" : sdomain + 1;
2960 rc = match_isinlist(sdomain, &arg, 0, &domainlist_anchor,
2961 sender_domain_cache, MCL_DOMAIN, TRUE, NULL);
2966 rc = match_address_list(sender_address, TRUE, TRUE, &arg,
2967 sender_address_cache, -1, 0, &sender_data);
2970 /* Connection variables must persist forever */
2974 int old_pool = store_pool;
2975 if (cb->u.varname[0] == 'c') store_pool = POOL_PERM;
2976 acl_var_create(cb->u.varname)->data.ptr = string_copy(arg);
2977 store_pool = old_pool;
2981 #ifdef WITH_CONTENT_SCAN
2984 /* Seperate the regular expression and any optional parameters. */
2985 uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size);
2986 /* Run the spam backend. */
2988 /* Modify return code based upon the existance of options. */
2989 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2991 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
2993 /* FAIL so that the message is passed to the next ACL */
3001 #ifdef EXPERIMENTAL_SPF
3003 rc = spf_process(&arg, sender_address, SPF_PROCESS_NORMAL);
3005 case ACLC_SPF_GUESS:
3006 rc = spf_process(&arg, sender_address, SPF_PROCESS_GUESS);
3010 /* If the verb is WARN, discard any user message from verification, because
3011 such messages are SMTP responses, not header additions. The latter come
3012 only from explicit "message" modifiers. However, put the user message into
3013 $acl_verify_message so it can be used in subsequent conditions or modifiers
3014 (until something changes it). */
3017 rc = acl_verify(where, addr, arg, user_msgptr, log_msgptr, basic_errno);
3018 acl_verify_message = *user_msgptr;
3019 if (verb == ACL_WARN) *user_msgptr = NULL;
3023 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown "
3024 "condition %d", cb->type);
3028 /* If a condition was negated, invert OK/FAIL. */
3030 if (!cond_modifiers[cb->type] && cb->u.negated)
3032 if (rc == OK) rc = FAIL;
3033 else if (rc == FAIL || rc == FAIL_DROP) rc = OK;
3036 if (rc != OK) break; /* Conditions loop */
3040 /* If the result is the one for which "message" and/or "log_message" are used,
3041 handle the values of these modifiers. If there isn't a log message set, we make
3042 it the same as the user message.
3044 "message" is a user message that will be included in an SMTP response. Unless
3045 it is empty, it overrides any previously set user message.
3047 "log_message" is a non-user message, and it adds to any existing non-user
3048 message that is already set.
3050 Most verbs have but a single return for which the messages are relevant, but
3051 for "discard", it's useful to have the log message both when it succeeds and
3052 when it fails. For "accept", the message is used in the OK case if there is no
3053 "endpass", but (for backwards compatibility) in the FAIL case if "endpass" is
3056 if (*epp && rc == OK) user_message = NULL;
3058 if (((1<<rc) & msgcond[verb]) != 0)
3061 uschar *old_user_msgptr = *user_msgptr;
3062 uschar *old_log_msgptr = (*log_msgptr != NULL)? *log_msgptr : old_user_msgptr;
3064 /* If the verb is "warn", messages generated by conditions (verification or
3065 nested ACLs) are always discarded. This also happens for acceptance verbs
3066 when they actually do accept. Only messages specified at this level are used.
3067 However, the value of an existing message is available in $acl_verify_message
3068 during expansions. */
3070 if (verb == ACL_WARN ||
3071 (rc == OK && (verb == ACL_ACCEPT || verb == ACL_DISCARD)))
3072 *log_msgptr = *user_msgptr = NULL;
3074 if (user_message != NULL)
3076 acl_verify_message = old_user_msgptr;
3077 expmessage = expand_string(user_message);
3078 if (expmessage == NULL)
3080 if (!expand_string_forcedfail)
3081 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
3082 user_message, expand_string_message);
3084 else if (expmessage[0] != 0) *user_msgptr = expmessage;
3087 if (log_message != NULL)
3089 acl_verify_message = old_log_msgptr;
3090 expmessage = expand_string(log_message);
3091 if (expmessage == NULL)
3093 if (!expand_string_forcedfail)
3094 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
3095 log_message, expand_string_message);
3097 else if (expmessage[0] != 0)
3099 *log_msgptr = (*log_msgptr == NULL)? expmessage :
3100 string_sprintf("%s: %s", expmessage, *log_msgptr);
3104 /* If no log message, default it to the user message */
3106 if (*log_msgptr == NULL) *log_msgptr = *user_msgptr;
3109 acl_verify_message = NULL;
3117 /*************************************************
3118 * Get line from a literal ACL *
3119 *************************************************/
3121 /* This function is passed to acl_read() in order to extract individual lines
3122 of a literal ACL, which we access via static pointers. We can destroy the
3123 contents because this is called only once (the compiled ACL is remembered).
3125 This code is intended to treat the data in the same way as lines in the main
3126 Exim configuration file. That is:
3128 . Leading spaces are ignored.
3130 . A \ at the end of a line is a continuation - trailing spaces after the \
3131 are permitted (this is because I don't believe in making invisible things
3132 significant). Leading spaces on the continued part of a line are ignored.
3134 . Physical lines starting (significantly) with # are totally ignored, and
3135 may appear within a sequence of backslash-continued lines.
3137 . Blank lines are ignored, but will end a sequence of continuations.
3140 Returns: a pointer to the next line
3144 static uschar *acl_text; /* Current pointer in the text */
3145 static uschar *acl_text_end; /* Points one past the terminating '0' */
3153 /* This loop handles leading blank lines and comments. */
3157 while (isspace(*acl_text)) acl_text++; /* Leading spaces/empty lines */
3158 if (*acl_text == 0) return NULL; /* No more data */
3159 yield = acl_text; /* Potential data line */
3161 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3163 /* If we hit the end before a newline, we have the whole logical line. If
3164 it's a comment, there's no more data to be given. Otherwise, yield it. */
3166 if (*acl_text == 0) return (*yield == '#')? NULL : yield;
3168 /* After reaching a newline, end this loop if the physical line does not
3169 start with '#'. If it does, it's a comment, and the loop continues. */
3171 if (*yield != '#') break;
3174 /* This loop handles continuations. We know we have some real data, ending in
3175 newline. See if there is a continuation marker at the end (ignoring trailing
3176 white space). We know that *yield is not white space, so no need to test for
3177 cont > yield in the backwards scanning loop. */
3182 for (cont = acl_text - 1; isspace(*cont); cont--);
3184 /* If no continuation follows, we are done. Mark the end of the line and
3193 /* We have encountered a continuation. Skip over whitespace at the start of
3194 the next line, and indeed the whole of the next line or lines if they are
3199 while (*(++acl_text) == ' ' || *acl_text == '\t');
3200 if (*acl_text != '#') break;
3201 while (*(++acl_text) != 0 && *acl_text != '\n');
3204 /* We have the start of a continuation line. Move all the rest of the data
3205 to join onto the previous line, and then find its end. If the end is not a
3206 newline, we are done. Otherwise loop to look for another continuation. */
3208 memmove(cont, acl_text, acl_text_end - acl_text);
3209 acl_text_end -= acl_text - cont;
3211 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3212 if (*acl_text == 0) return yield;
3215 /* Control does not reach here */
3222 /*************************************************
3223 * Check access using an ACL *
3224 *************************************************/
3226 /* This function is called from address_check. It may recurse via
3227 acl_check_condition() - hence the use of a level to stop looping. The ACL is
3228 passed as a string which is expanded. A forced failure implies no access check
3229 is required. If the result is a single word, it is taken as the name of an ACL
3230 which is sought in the global ACL tree. Otherwise, it is taken as literal ACL
3231 text, complete with newlines, and parsed as such. In both cases, the ACL check
3232 is then run. This function uses an auxiliary function for acl_read() to call
3233 for reading individual lines of a literal ACL. This is acl_getline(), which
3234 appears immediately above.
3237 where where called from
3238 addr address item when called from RCPT; otherwise NULL
3239 s the input string; NULL is the same as an empty ACL => DENY
3240 level the nesting level
3241 user_msgptr where to put a user error (for SMTP response)
3242 log_msgptr where to put a logging message (not for SMTP response)
3244 Returns: OK access is granted
3245 DISCARD access is apparently granted...
3246 FAIL access is denied
3247 FAIL_DROP access is denied; drop the connection
3248 DEFER can't tell at the moment
3253 acl_check_internal(int where, address_item *addr, uschar *s, int level,
3254 uschar **user_msgptr, uschar **log_msgptr)
3257 acl_block *acl = NULL;
3258 uschar *acl_name = US"inline ACL";
3261 /* Catch configuration loops */
3265 *log_msgptr = US"ACL nested too deep: possible loop";
3271 HDEBUG(D_acl) debug_printf("ACL is NULL: implicit DENY\n");
3275 /* At top level, we expand the incoming string. At lower levels, it has already
3276 been expanded as part of condition processing. */
3280 ss = expand_string(s);
3283 if (expand_string_forcedfail) return OK;
3284 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s", s,
3285 expand_string_message);
3291 while (isspace(*ss))ss++;
3293 /* If we can't find a named ACL, the default is to parse it as an inline one.
3294 (Unless it begins with a slash; non-existent files give rise to an error.) */
3298 /* Handle the case of a string that does not contain any spaces. Look for a
3299 named ACL among those read from the configuration, or a previously read file.
3300 It is possible that the pointer to the ACL is NULL if the configuration
3301 contains a name with no data. If not found, and the text begins with '/',
3302 read an ACL from a file, and save it so it can be re-used. */
3304 if (Ustrchr(ss, ' ') == NULL)
3306 tree_node *t = tree_search(acl_anchor, ss);
3309 acl = (acl_block *)(t->data.ptr);
3312 HDEBUG(D_acl) debug_printf("ACL \"%s\" is empty: implicit DENY\n", ss);
3315 acl_name = string_sprintf("ACL \"%s\"", ss);
3316 HDEBUG(D_acl) debug_printf("using ACL \"%s\"\n", ss);
3319 else if (*ss == '/')
3321 struct stat statbuf;
3322 fd = Uopen(ss, O_RDONLY, 0);
3325 *log_msgptr = string_sprintf("failed to open ACL file \"%s\": %s", ss,
3330 if (fstat(fd, &statbuf) != 0)
3332 *log_msgptr = string_sprintf("failed to fstat ACL file \"%s\": %s", ss,
3337 acl_text = store_get(statbuf.st_size + 1);
3338 acl_text_end = acl_text + statbuf.st_size + 1;
3340 if (read(fd, acl_text, statbuf.st_size) != statbuf.st_size)
3342 *log_msgptr = string_sprintf("failed to read ACL file \"%s\": %s",
3343 ss, strerror(errno));
3346 acl_text[statbuf.st_size] = 0;
3349 acl_name = string_sprintf("ACL \"%s\"", ss);
3350 HDEBUG(D_acl) debug_printf("read ACL from file %s\n", ss);
3354 /* Parse an ACL that is still in text form. If it came from a file, remember it
3355 in the ACL tree, having read it into the POOL_PERM store pool so that it
3356 persists between multiple messages. */
3360 int old_pool = store_pool;
3361 if (fd >= 0) store_pool = POOL_PERM;
3362 acl = acl_read(acl_getline, log_msgptr);
3363 store_pool = old_pool;
3364 if (acl == NULL && *log_msgptr != NULL) return ERROR;
3367 tree_node *t = store_get_perm(sizeof(tree_node) + Ustrlen(ss));
3368 Ustrcpy(t->name, ss);
3370 (void)tree_insertnode(&acl_anchor, t);
3374 /* Now we have an ACL to use. It's possible it may be NULL. */
3379 int basic_errno = 0;
3380 BOOL endpass_seen = FALSE;
3382 *log_msgptr = *user_msgptr = NULL;
3383 acl_temp_details = FALSE;
3385 if ((where == ACL_WHERE_QUIT || where == ACL_WHERE_NOTQUIT) &&
3386 acl->verb != ACL_ACCEPT &&
3387 acl->verb != ACL_WARN)
3389 *log_msgptr = string_sprintf("\"%s\" is not allowed in a QUIT or not-QUIT ACL",
3394 HDEBUG(D_acl) debug_printf("processing \"%s\"\n", verbs[acl->verb]);
3396 /* Clear out any search error message from a previous check before testing
3399 search_error_message = NULL;
3400 cond = acl_check_condition(acl->verb, acl->condition, where, addr, level,
3401 &endpass_seen, user_msgptr, log_msgptr, &basic_errno);
3403 /* Handle special returns: DEFER causes a return except on a WARN verb;
3404 ERROR always causes a return. */
3409 HDEBUG(D_acl) debug_printf("%s: condition test deferred\n", verbs[acl->verb]);
3410 if (basic_errno != ERRNO_CALLOUTDEFER)
3412 if (search_error_message != NULL && *search_error_message != 0)
3413 *log_msgptr = search_error_message;
3414 if (smtp_return_error_details) acl_temp_details = TRUE;
3418 acl_temp_details = TRUE;
3420 if (acl->verb != ACL_WARN) return DEFER;
3423 default: /* Paranoia */
3425 HDEBUG(D_acl) debug_printf("%s: condition test error\n", verbs[acl->verb]);
3429 HDEBUG(D_acl) debug_printf("%s: condition test succeeded\n",
3434 HDEBUG(D_acl) debug_printf("%s: condition test failed\n", verbs[acl->verb]);
3437 /* DISCARD and DROP can happen only from a nested ACL condition, and
3438 DISCARD can happen only for an "accept" or "discard" verb. */
3441 HDEBUG(D_acl) debug_printf("%s: condition test yielded \"discard\"\n",
3446 HDEBUG(D_acl) debug_printf("%s: condition test yielded \"drop\"\n",
3451 /* At this point, cond for most verbs is either OK or FAIL or (as a result of
3452 a nested ACL condition) FAIL_DROP. However, for WARN, cond may be DEFER, and
3453 for ACCEPT and DISCARD, it may be DISCARD after a nested ACL call. */
3458 if (cond == OK || cond == DISCARD) return cond;
3461 HDEBUG(D_acl) debug_printf("accept: endpass encountered - denying access\n");
3469 acl_temp_details = TRUE;
3475 if (cond == OK) return FAIL;
3479 if (cond == OK || cond == DISCARD) return DISCARD;
3482 HDEBUG(D_acl) debug_printf("discard: endpass encountered - denying access\n");
3488 if (cond == OK) return FAIL_DROP;
3492 if (cond != OK) return cond;
3497 acl_warn(where, *user_msgptr, *log_msgptr);
3498 else if (cond == DEFER && (log_extra_selector & LX_acl_warn_skipped) != 0)
3499 log_write(0, LOG_MAIN, "%s Warning: ACL \"warn\" statement skipped: "
3500 "condition test deferred%s%s", host_and_ident(TRUE),
3501 (*log_msgptr == NULL)? US"" : US": ",
3502 (*log_msgptr == NULL)? US"" : *log_msgptr);
3503 *log_msgptr = *user_msgptr = NULL; /* In case implicit DENY follows */
3507 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown verb %d",
3512 /* Pass to the next ACL item */
3517 /* We have reached the end of the ACL. This is an implicit DENY. */
3519 HDEBUG(D_acl) debug_printf("end of %s: implicit DENY\n", acl_name);
3524 /*************************************************
3525 * Check access using an ACL *
3526 *************************************************/
3528 /* This is the external interface for ACL checks. It sets up an address and the
3529 expansions for $domain and $local_part when called after RCPT, then calls
3530 acl_check_internal() to do the actual work.
3533 where ACL_WHERE_xxxx indicating where called from
3534 recipient RCPT address for RCPT check, else NULL
3535 s the input string; NULL is the same as an empty ACL => DENY
3536 user_msgptr where to put a user error (for SMTP response)
3537 log_msgptr where to put a logging message (not for SMTP response)
3539 Returns: OK access is granted by an ACCEPT verb
3540 DISCARD access is granted by a DISCARD verb
3541 FAIL access is denied
3542 FAIL_DROP access is denied; drop the connection
3543 DEFER can't tell at the moment
3548 acl_check(int where, uschar *recipient, uschar *s, uschar **user_msgptr,
3549 uschar **log_msgptr)
3553 address_item *addr = NULL;
3555 *user_msgptr = *log_msgptr = NULL;
3556 sender_verified_failed = NULL;
3557 ratelimiters_cmd = NULL;
3558 log_reject_target = LOG_MAIN|LOG_REJECT;
3560 if (where == ACL_WHERE_RCPT)
3562 adb = address_defaults;
3564 addr->address = recipient;
3565 if (deliver_split_address(addr) == DEFER)
3567 *log_msgptr = US"defer in percent_hack_domains check";
3570 deliver_domain = addr->domain;
3571 deliver_localpart = addr->local_part;
3574 rc = acl_check_internal(where, addr, s, 0, user_msgptr, log_msgptr);
3576 deliver_domain = deliver_localpart = deliver_address_data =
3577 sender_address_data = NULL;
3579 /* A DISCARD response is permitted only for message ACLs, excluding the PREDATA
3580 ACL, which is really in the middle of an SMTP command. */
3584 if (where > ACL_WHERE_NOTSMTP || where == ACL_WHERE_PREDATA)
3586 log_write(0, LOG_MAIN|LOG_PANIC, "\"discard\" verb not allowed in %s "
3587 "ACL", acl_wherenames[where]);
3593 /* A DROP response is not permitted from MAILAUTH */
3595 if (rc == FAIL_DROP && where == ACL_WHERE_MAILAUTH)
3597 log_write(0, LOG_MAIN|LOG_PANIC, "\"drop\" verb not allowed in %s "
3598 "ACL", acl_wherenames[where]);
3602 /* Before giving a response, take a look at the length of any user message, and
3603 split it up into multiple lines if possible. */
3605 *user_msgptr = string_split_message(*user_msgptr);
3606 if (fake_response != OK)
3607 fake_response_text = string_split_message(fake_response_text);
3614 /*************************************************
3615 * Create ACL variable *
3616 *************************************************/
3618 /* Create an ACL variable or reuse an existing one. ACL variables are in a
3619 binary tree (see tree.c) with acl_var_c and acl_var_m as root nodes.
3622 name pointer to the variable's name, starting with c or m
3624 Returns the pointer to variable's tree node
3628 acl_var_create(uschar *name)
3630 tree_node *node, **root;
3631 root = (name[0] == 'c')? &acl_var_c : &acl_var_m;
3632 node = tree_search(*root, name);
3635 node = store_get(sizeof(tree_node) + Ustrlen(name));
3636 Ustrcpy(node->name, name);
3637 (void)tree_insertnode(root, node);
3639 node->data.ptr = NULL;
3645 /*************************************************
3646 * Write an ACL variable in spool format *
3647 *************************************************/
3649 /* This function is used as a callback for tree_walk when writing variables to
3650 the spool file. To retain spool file compatibility, what is written is -aclc or
3651 -aclm followed by the rest of the name and the data length, space separated,
3652 then the value itself, starting on a new line, and terminated by an additional
3653 newline. When we had only numbered ACL variables, the first line might look
3654 like this: "-aclc 5 20". Now it might be "-aclc foo 20" for the variable called
3658 name of the variable
3659 value of the variable
3660 ctx FILE pointer (as a void pointer)
3666 acl_var_write(uschar *name, uschar *value, void *ctx)
3668 FILE *f = (FILE *)ctx;
3669 fprintf(f, "-acl%c %s %d\n%s\n", name[0], name+1, Ustrlen(value), value);