1 /* $Cambridge: exim/src/src/acl.c,v 1.35 2005/05/25 09:58:16 fanf2 Exp $ */
3 /*************************************************
4 * Exim - an Internet mail transport agent *
5 *************************************************/
7 /* Copyright (c) University of Cambridge 1995 - 2005 */
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 condition for which "message" is used */
32 static int msgcond[] = { FAIL, OK, OK, FAIL, OK, FAIL, OK };
34 /* ACL condition and modifier codes - keep in step with the table that
37 enum { ACLC_ACL, ACLC_AUTHENTICATED,
38 #ifdef EXPERIMENTAL_BRIGHTMAIL
41 ACLC_CONDITION, ACLC_CONTROL,
42 #ifdef WITH_CONTENT_SCAN
46 #ifdef WITH_OLD_DEMIME
49 #ifdef EXPERIMENTAL_DOMAINKEYS
50 ACLC_DK_DOMAIN_SOURCE,
52 ACLC_DK_SENDER_DOMAINS,
53 ACLC_DK_SENDER_LOCAL_PARTS,
57 ACLC_DNSLISTS, ACLC_DOMAINS, ACLC_ENCRYPTED, ACLC_ENDPASS,
58 ACLC_HOSTS, ACLC_LOCAL_PARTS, ACLC_LOG_MESSAGE, ACLC_LOGWRITE,
59 #ifdef WITH_CONTENT_SCAN
63 #ifdef WITH_CONTENT_SCAN
68 #ifdef WITH_CONTENT_SCAN
71 ACLC_SENDER_DOMAINS, ACLC_SENDERS, ACLC_SET,
72 #ifdef WITH_CONTENT_SCAN
75 #ifdef EXPERIMENTAL_SPF
80 /* ACL conditions/modifiers: "delay", "control", "endpass", "message",
81 "log_message", "logwrite", and "set" are modifiers that look like conditions
82 but always return TRUE. They are used for their side effects. */
84 static uschar *conditions[] = { US"acl", US"authenticated",
85 #ifdef EXPERIMENTAL_BRIGHTMAIL
90 #ifdef WITH_CONTENT_SCAN
94 #ifdef WITH_OLD_DEMIME
97 #ifdef EXPERIMENTAL_DOMAINKEYS
100 US"dk_sender_domains",
101 US"dk_sender_local_parts",
105 US"dnslists", US"domains", US"encrypted",
106 US"endpass", US"hosts", US"local_parts", US"log_message", US"logwrite",
107 #ifdef WITH_CONTENT_SCAN
111 #ifdef WITH_CONTENT_SCAN
116 #ifdef WITH_CONTENT_SCAN
119 US"sender_domains", US"senders", US"set",
120 #ifdef WITH_CONTENT_SCAN
123 #ifdef EXPERIMENTAL_SPF
128 /* ACL control names */
130 static uschar *controls[] = { US"error", US"caseful_local_part",
131 US"caselower_local_part", US"enforce_sync", US"no_enforce_sync", US"freeze",
132 US"queue_only", US"submission", US"no_multiline"};
134 /* Flags to indicate for which conditions /modifiers a string expansion is done
135 at the outer level. In the other cases, expansion already occurs in the
136 checking functions. */
138 static uschar cond_expand_at_top[] = {
140 FALSE, /* authenticated */
141 #ifdef EXPERIMENTAL_BRIGHTMAIL
142 TRUE, /* bmi_optin */
144 TRUE, /* condition */
146 #ifdef WITH_CONTENT_SCAN
150 #ifdef WITH_OLD_DEMIME
153 #ifdef EXPERIMENTAL_DOMAINKEYS
154 TRUE, /* dk_domain_source */
155 TRUE, /* dk_policy */
156 TRUE, /* dk_sender_domains */
157 TRUE, /* dk_sender_local_parts */
158 TRUE, /* dk_senders */
159 TRUE, /* dk_status */
163 FALSE, /* encrypted */
166 FALSE, /* local_parts */
167 TRUE, /* log_message */
169 #ifdef WITH_CONTENT_SCAN
173 #ifdef WITH_CONTENT_SCAN
174 TRUE, /* mime_regex */
176 TRUE, /* ratelimit */
177 FALSE, /* recipients */
178 #ifdef WITH_CONTENT_SCAN
181 FALSE, /* sender_domains */
184 #ifdef WITH_CONTENT_SCAN
187 #ifdef EXPERIMENTAL_SPF
193 /* Flags to identify the modifiers */
195 static uschar cond_modifiers[] = {
197 FALSE, /* authenticated */
198 #ifdef EXPERIMENTAL_BRIGHTMAIL
199 TRUE, /* bmi_optin */
201 FALSE, /* condition */
203 #ifdef WITH_CONTENT_SCAN
207 #ifdef WITH_OLD_DEMIME
210 #ifdef EXPERIMENTAL_DOMAINKEYS
211 FALSE, /* dk_domain_source */
212 FALSE, /* dk_policy */
213 FALSE, /* dk_sender_domains */
214 FALSE, /* dk_sender_local_parts */
215 FALSE, /* dk_senders */
216 FALSE, /* dk_status */
218 FALSE, /* dnslists */
220 FALSE, /* encrypted */
223 FALSE, /* local_parts */
224 TRUE, /* log_message */
226 #ifdef WITH_CONTENT_SCAN
230 #ifdef WITH_CONTENT_SCAN
231 FALSE, /* mime_regex */
233 FALSE, /* ratelimit */
234 FALSE, /* recipients */
235 #ifdef WITH_CONTENT_SCAN
238 FALSE, /* sender_domains */
241 #ifdef WITH_CONTENT_SCAN
244 #ifdef EXPERIMENTAL_SPF
250 /* Bit map vector of which conditions are not allowed at certain times. For
251 each condition, there's a bitmap of dis-allowed times. For some, it is easier
252 to specify the negation of a small number of allowed times. */
254 static unsigned int cond_forbids[] = {
257 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_CONNECT)| /* authenticated */
260 #ifdef EXPERIMENTAL_BRIGHTMAIL
261 (1<<ACL_WHERE_AUTH)| /* bmi_optin */
262 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
263 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_MIME)|
264 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
265 (1<<ACL_WHERE_MAILAUTH)|
266 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
267 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_PREDATA),
272 /* Certain types of control are always allowed, so we let it through
273 always and check in the control processing itself. */
277 #ifdef WITH_CONTENT_SCAN
279 ~(1<<ACL_WHERE_MIME), /* decode */
284 #ifdef WITH_OLD_DEMIME
286 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)), /* demime */
289 #ifdef EXPERIMENTAL_DOMAINKEYS
290 (1<<ACL_WHERE_AUTH)| /* dk_domain_source */
291 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
292 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
293 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
294 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
295 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
298 (1<<ACL_WHERE_AUTH)| /* dk_policy */
299 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
300 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
301 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
302 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
303 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
306 (1<<ACL_WHERE_AUTH)| /* dk_sender_domains */
307 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
308 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
309 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
310 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
311 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
314 (1<<ACL_WHERE_AUTH)| /* dk_sender_local_parts */
315 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
316 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
317 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
318 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
319 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
322 (1<<ACL_WHERE_AUTH)| /* dk_senders */
323 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
324 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
325 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
326 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
327 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
330 (1<<ACL_WHERE_AUTH)| /* dk_status */
331 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
332 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
333 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
334 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
335 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
339 (1<<ACL_WHERE_NOTSMTP), /* dnslists */
342 ~(1<<ACL_WHERE_RCPT), /* domains */
344 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_CONNECT)| /* encrypted */
349 (1<<ACL_WHERE_NOTSMTP), /* hosts */
352 ~(1<<ACL_WHERE_RCPT), /* local_parts */
358 #ifdef WITH_CONTENT_SCAN
360 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)), /* malware */
365 #ifdef WITH_CONTENT_SCAN
367 ~(1<<ACL_WHERE_MIME), /* mime_regex */
373 ~(1<<ACL_WHERE_RCPT), /* recipients */
375 #ifdef WITH_CONTENT_SCAN
377 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* regex */
378 (1<<ACL_WHERE_MIME)),
381 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* sender_domains */
383 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
384 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
385 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
387 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* senders */
389 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
390 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
391 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
395 #ifdef WITH_CONTENT_SCAN
397 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)), /* spam */
400 #ifdef EXPERIMENTAL_SPF
401 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* spf */
403 (1<<ACL_WHERE_MAILAUTH)|
404 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
405 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
408 /* Certain types of verify are always allowed, so we let it through
409 always and check in the verify function itself */
415 /* Return values from decode_control() */
418 #ifdef EXPERIMENTAL_BRIGHTMAIL
421 #ifdef EXPERIMENTAL_DOMAINKEYS
424 CONTROL_ERROR, CONTROL_CASEFUL_LOCAL_PART, CONTROL_CASELOWER_LOCAL_PART,
425 CONTROL_ENFORCE_SYNC, CONTROL_NO_ENFORCE_SYNC, CONTROL_FREEZE,
426 CONTROL_QUEUE_ONLY, CONTROL_SUBMISSION,
427 #ifdef WITH_CONTENT_SCAN
428 CONTROL_NO_MBOX_UNSPOOL,
430 CONTROL_FAKEDEFER, CONTROL_FAKEREJECT, CONTROL_NO_MULTILINE };
432 /* Bit map vector of which controls are not allowed at certain times. For
433 each control, there's a bitmap of dis-allowed times. For some, it is easier to
434 specify the negation of a small number of allowed times. */
436 static unsigned int control_forbids[] = {
437 #ifdef EXPERIMENTAL_BRIGHTMAIL
440 #ifdef EXPERIMENTAL_DOMAINKEYS
441 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), /* dk_verify */
447 ~(1<<ACL_WHERE_RCPT), /* caseful_local_part */
450 ~(1<<ACL_WHERE_RCPT), /* caselower_local_part */
452 (1<<ACL_WHERE_NOTSMTP), /* enforce_sync */
454 (1<<ACL_WHERE_NOTSMTP), /* no_enforce_sync */
457 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* freeze */
458 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
459 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)),
462 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* queue_only */
463 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
464 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)),
467 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* submission */
468 (1<<ACL_WHERE_PREDATA)),
470 #ifdef WITH_CONTENT_SCAN
472 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* no_mbox_unspool */
473 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
474 (1<<ACL_WHERE_MIME)),
478 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakedefer */
479 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
480 (1<<ACL_WHERE_MIME)),
483 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakereject */
484 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
485 (1<<ACL_WHERE_MIME)),
487 (1<<ACL_WHERE_NOTSMTP) /* no_multiline */
490 /* Structure listing various control arguments, with their characteristics. */
492 typedef struct control_def {
494 int value; /* CONTROL_xxx value */
495 BOOL has_option; /* Has /option(s) following */
498 static control_def controls_list[] = {
499 #ifdef EXPERIMENTAL_BRIGHTMAIL
500 { US"bmi_run", CONTROL_BMI_RUN, FALSE},
502 #ifdef EXPERIMENTAL_DOMAINKEYS
503 { US"dk_verify", CONTROL_DK_VERIFY, FALSE},
505 { US"caseful_local_part", CONTROL_CASEFUL_LOCAL_PART, FALSE},
506 { US"caselower_local_part", CONTROL_CASELOWER_LOCAL_PART, FALSE},
507 { US"enforce_sync", CONTROL_ENFORCE_SYNC, FALSE},
508 { US"freeze", CONTROL_FREEZE, FALSE},
509 { US"no_enforce_sync", CONTROL_NO_ENFORCE_SYNC, FALSE},
510 { US"no_multiline_responses", CONTROL_NO_MULTILINE, FALSE},
511 { US"queue_only", CONTROL_QUEUE_ONLY, FALSE},
512 #ifdef WITH_CONTENT_SCAN
513 { US"no_mbox_unspool", CONTROL_NO_MBOX_UNSPOOL, FALSE},
515 { US"fakedefer", CONTROL_FAKEDEFER, TRUE},
516 { US"fakereject", CONTROL_FAKEREJECT, TRUE},
517 { US"submission", CONTROL_SUBMISSION, TRUE}
520 /* Support data structures for Client SMTP Authorization. acl_verify_csa()
521 caches its result in a tree to avoid repeated DNS queries. The result is an
522 integer code which is used as an index into the following tables of
523 explanatory strings and verification return codes. */
525 static tree_node *csa_cache = NULL;
527 enum { CSA_UNKNOWN, CSA_OK, CSA_DEFER_SRV, CSA_DEFER_ADDR,
528 CSA_FAIL_EXPLICIT, CSA_FAIL_DOMAIN, CSA_FAIL_NOADDR, CSA_FAIL_MISMATCH };
530 /* The acl_verify_csa() return code is translated into an acl_verify() return
531 code using the following table. It is OK unless the client is definitely not
532 authorized. This is because CSA is supposed to be optional for sending sites,
533 so recipients should not be too strict about checking it - especially because
534 DNS problems are quite likely to occur. It's possible to use $csa_status in
535 further ACL conditions to distinguish ok, unknown, and defer if required, but
536 the aim is to make the usual configuration simple. */
538 static int csa_return_code[] = {
540 FAIL, FAIL, FAIL, FAIL
543 static uschar *csa_status_string[] = {
544 US"unknown", US"ok", US"defer", US"defer",
545 US"fail", US"fail", US"fail", US"fail"
548 static uschar *csa_reason_string[] = {
551 US"deferred (SRV lookup failed)",
552 US"deferred (target address lookup failed)",
553 US"failed (explicit authorization required)",
554 US"failed (host name not authorized)",
555 US"failed (no authorized addresses)",
556 US"failed (client address mismatch)"
559 /* Enable recursion between acl_check_internal() and acl_check_condition() */
561 static int acl_check_internal(int, address_item *, uschar *, int, uschar **,
565 /*************************************************
566 * Pick out name from list *
567 *************************************************/
569 /* Use a binary chop method
576 Returns: offset in list, or -1 if not found
580 acl_checkname(uschar *name, uschar **list, int end)
586 int mid = (start + end)/2;
587 int c = Ustrcmp(name, list[mid]);
588 if (c == 0) return mid;
589 if (c < 0) end = mid; else start = mid + 1;
596 /*************************************************
597 * Read and parse one ACL *
598 *************************************************/
600 /* This function is called both from readconf in order to parse the ACLs in the
601 configuration file, and also when an ACL is encountered dynamically (e.g. as
602 the result of an expansion). It is given a function to call in order to
603 retrieve the lines of the ACL. This function handles skipping comments and
604 blank lines (where relevant).
607 func function to get next line of ACL
608 error where to put an error message
610 Returns: pointer to ACL, or NULL
611 NULL can be legal (empty ACL); in this case error will be NULL
615 acl_read(uschar *(*func)(void), uschar **error)
617 acl_block *yield = NULL;
618 acl_block **lastp = &yield;
619 acl_block *this = NULL;
620 acl_condition_block *cond;
621 acl_condition_block **condp = NULL;
626 while ((s = (*func)()) != NULL)
629 BOOL negated = FALSE;
630 uschar *saveline = s;
633 /* Conditions (but not verbs) are allowed to be negated by an initial
636 while (isspace(*s)) s++;
643 /* Read the name of a verb or a condition, or the start of a new ACL, which
644 can be started by a name, or by a macro definition. */
646 s = readconf_readname(name, sizeof(name), s);
647 if (*s == ':' || isupper(name[0] && *s == '=')) return yield;
649 /* If a verb is unrecognized, it may be another condition or modifier that
650 continues the previous verb. */
652 v = acl_checkname(name, verbs, sizeof(verbs)/sizeof(char *));
657 *error = string_sprintf("unknown ACL verb in \"%s\"", saveline);
668 *error = string_sprintf("malformed ACL line \"%s\"", saveline);
671 this = store_get(sizeof(acl_block));
673 lastp = &(this->next);
676 this->condition = NULL;
677 condp = &(this->condition);
678 if (*s == 0) continue; /* No condition on this line */
684 s = readconf_readname(name, sizeof(name), s); /* Condition name */
687 /* Handle a condition or modifier. */
689 c = acl_checkname(name, conditions, sizeof(conditions)/sizeof(char *));
692 *error = string_sprintf("unknown ACL condition/modifier in \"%s\"",
697 /* The modifiers may not be negated */
699 if (negated && cond_modifiers[c])
701 *error = string_sprintf("ACL error: negation is not allowed with "
702 "\"%s\"", conditions[c]);
706 /* ENDPASS may occur only with ACCEPT or DISCARD. */
708 if (c == ACLC_ENDPASS &&
709 this->verb != ACL_ACCEPT &&
710 this->verb != ACL_DISCARD)
712 *error = string_sprintf("ACL error: \"%s\" is not allowed with \"%s\"",
713 conditions[c], verbs[this->verb]);
717 cond = store_get(sizeof(acl_condition_block));
720 cond->u.negated = negated;
723 condp = &(cond->next);
725 /* The "set" modifier is different in that its argument is "name=value"
726 rather than just a value, and we can check the validity of the name, which
727 gives us a variable number to insert into the data block. */
731 if (Ustrncmp(s, "acl_", 4) != 0 || (s[4] != 'c' && s[4] != 'm') ||
732 !isdigit(s[5]) || (!isspace(s[6]) && s[6] != '='))
734 *error = string_sprintf("unrecognized name after \"set\" in ACL "
735 "modifier \"set %s\"", s);
739 cond->u.varnumber = s[5] - '0';
740 if (s[4] == 'm') cond->u.varnumber += ACL_C_MAX;
742 while (isspace(*s)) s++;
745 /* For "set", we are now positioned for the data. For the others, only
746 "endpass" has no data */
748 if (c != ACLC_ENDPASS)
752 *error = string_sprintf("\"=\" missing after ACL \"%s\" %s", name,
753 cond_modifiers[c]? US"modifier" : US"condition");
756 while (isspace(*s)) s++;
757 cond->arg = string_copy(s);
766 /*************************************************
768 *************************************************/
770 /* This function is called when a WARN verb's conditions are true. It adds to
771 the message's headers, and/or writes information to the log. In each case, this
772 only happens once (per message for headers, per connection for log).
775 where ACL_WHERE_xxxx indicating which ACL this is
776 user_message message for adding to headers
777 log_message message for logging, if different
783 acl_warn(int where, uschar *user_message, uschar *log_message)
787 if (log_message != NULL && log_message != user_message)
792 text = string_sprintf("%s Warning: %s", host_and_ident(TRUE),
793 string_printing(log_message));
795 /* If a sender verification has failed, and the log message is "sender verify
796 failed", add the failure message. */
798 if (sender_verified_failed != NULL &&
799 sender_verified_failed->message != NULL &&
800 strcmpic(log_message, US"sender verify failed") == 0)
801 text = string_sprintf("%s: %s", text, sender_verified_failed->message);
803 /* Search previously logged warnings. They are kept in malloc
804 store so they can be freed at the start of a new message. */
806 for (logged = acl_warn_logged; logged != NULL; logged = logged->next)
807 if (Ustrcmp(logged->text, text) == 0) break;
811 int length = Ustrlen(text) + 1;
812 log_write(0, LOG_MAIN, "%s", text);
813 logged = store_malloc(sizeof(string_item) + length);
814 logged->text = (uschar *)logged + sizeof(string_item);
815 memcpy(logged->text, text, length);
816 logged->next = acl_warn_logged;
817 acl_warn_logged = logged;
821 /* If there's no user message, we are done. */
823 if (user_message == NULL) return;
825 /* If this isn't a message ACL, we can't do anything with a user message.
828 if (where > ACL_WHERE_NOTSMTP)
830 log_write(0, LOG_MAIN|LOG_PANIC, "ACL \"warn\" with \"message\" setting "
831 "found in a non-message (%s) ACL: cannot specify header lines here: "
832 "message ignored", acl_wherenames[where]);
836 /* Treat the user message as a sequence of one or more header lines. */
838 hlen = Ustrlen(user_message);
841 uschar *text, *p, *q;
843 /* Add a final newline if not present */
845 text = ((user_message)[hlen-1] == '\n')? user_message :
846 string_sprintf("%s\n", user_message);
848 /* Loop for multiple header lines, taking care about continuations */
850 for (p = q = text; *p != 0; )
853 int newtype = htype_add_bot;
854 header_line **hptr = &acl_warn_headers;
856 /* Find next header line within the string */
860 q = Ustrchr(q, '\n');
861 if (*(++q) != ' ' && *q != '\t') break;
864 /* If the line starts with a colon, interpret the instruction for where to
865 add it. This temporarily sets up a new type. */
869 if (strncmpic(p, US":after_received:", 16) == 0)
871 newtype = htype_add_rec;
874 else if (strncmpic(p, US":at_start_rfc:", 14) == 0)
876 newtype = htype_add_rfc;
879 else if (strncmpic(p, US":at_start:", 10) == 0)
881 newtype = htype_add_top;
884 else if (strncmpic(p, US":at_end:", 8) == 0)
886 newtype = htype_add_bot;
889 while (*p == ' ' || *p == '\t') p++;
892 /* See if this line starts with a header name, and if not, add X-ACL-Warn:
893 to the front of it. */
895 for (s = p; s < q - 1; s++)
897 if (*s == ':' || !isgraph(*s)) break;
900 s = string_sprintf("%s%.*s", (*s == ':')? "" : "X-ACL-Warn: ", q - p, p);
903 /* See if this line has already been added */
905 while (*hptr != NULL)
907 if (Ustrncmp((*hptr)->text, s, hlen) == 0) break;
908 hptr = &((*hptr)->next);
911 /* Add if not previously present */
915 header_line *h = store_get(sizeof(header_line));
924 /* Advance for next header line within the string */
933 /*************************************************
934 * Verify and check reverse DNS *
935 *************************************************/
937 /* Called from acl_verify() below. We look up the host name(s) of the client IP
938 address if this has not yet been done. The host_name_lookup() function checks
939 that one of these names resolves to an address list that contains the client IP
940 address, so we don't actually have to do the check here.
943 user_msgptr pointer for user message
944 log_msgptr pointer for log message
946 Returns: OK verification condition succeeded
947 FAIL verification failed
948 DEFER there was a problem verifying
952 acl_verify_reverse(uschar **user_msgptr, uschar **log_msgptr)
956 user_msgptr = user_msgptr; /* stop compiler warning */
958 /* Previous success */
960 if (sender_host_name != NULL) return OK;
962 /* Previous failure */
964 if (host_lookup_failed)
966 *log_msgptr = string_sprintf("host lookup failed%s", host_lookup_msg);
970 /* Need to do a lookup */
973 debug_printf("looking up host name to force name/address consistency check\n");
975 if ((rc = host_name_lookup()) != OK)
977 *log_msgptr = (rc == DEFER)?
978 US"host lookup deferred for reverse lookup check"
980 string_sprintf("host lookup failed for reverse lookup check%s",
982 return rc; /* DEFER or FAIL */
985 host_build_sender_fullhost();
991 /*************************************************
992 * Check client IP address matches CSA target *
993 *************************************************/
995 /* Called from acl_verify_csa() below. This routine scans a section of a DNS
996 response for address records belonging to the CSA target hostname. The section
997 is specified by the reset argument, either RESET_ADDITIONAL or RESET_ANSWERS.
998 If one of the addresses matches the client's IP address, then the client is
999 authorized by CSA. If there are target IP addresses but none of them match
1000 then the client is using an unauthorized IP address. If there are no target IP
1001 addresses then the client cannot be using an authorized IP address. (This is
1002 an odd configuration - why didn't the SRV record have a weight of 1 instead?)
1005 dnsa the DNS answer block
1006 dnss a DNS scan block for us to use
1007 reset option specifing what portion to scan, as described above
1008 target the target hostname to use for matching RR names
1010 Returns: CSA_OK successfully authorized
1011 CSA_FAIL_MISMATCH addresses found but none matched
1012 CSA_FAIL_NOADDR no target addresses found
1016 acl_verify_csa_address(dns_answer *dnsa, dns_scan *dnss, int reset,
1022 BOOL target_found = FALSE;
1024 for (rr = dns_next_rr(dnsa, dnss, reset);
1026 rr = dns_next_rr(dnsa, dnss, RESET_NEXT))
1028 /* Check this is an address RR for the target hostname. */
1032 && rr->type != T_AAAA
1039 if (strcmpic(target, rr->name) != 0) continue;
1041 target_found = TRUE;
1043 /* Turn the target address RR into a list of textual IP addresses and scan
1044 the list. There may be more than one if it is an A6 RR. */
1046 for (da = dns_address_from_rr(dnsa, rr); da != NULL; da = da->next)
1048 /* If the client IP address matches the target IP address, it's good! */
1050 DEBUG(D_acl) debug_printf("CSA target address is %s\n", da->address);
1052 if (strcmpic(sender_host_address, da->address) == 0) return CSA_OK;
1056 /* If we found some target addresses but none of them matched, the client is
1057 using an unauthorized IP address, otherwise the target has no authorized IP
1060 if (target_found) return CSA_FAIL_MISMATCH;
1061 else return CSA_FAIL_NOADDR;
1066 /*************************************************
1067 * Verify Client SMTP Authorization *
1068 *************************************************/
1070 /* Called from acl_verify() below. This routine calls dns_lookup_special()
1071 to find the CSA SRV record corresponding to the domain argument, or
1072 $sender_helo_name if no argument is provided. It then checks that the
1073 client is authorized, and that its IP address corresponds to the SRV
1074 target's address by calling acl_verify_csa_address() above. The address
1075 should have been returned in the DNS response's ADDITIONAL section, but if
1076 not we perform another DNS lookup to get it.
1079 domain pointer to optional parameter following verify = csa
1081 Returns: CSA_UNKNOWN no valid CSA record found
1082 CSA_OK successfully authorized
1083 CSA_FAIL_* client is definitely not authorized
1084 CSA_DEFER_* there was a DNS problem
1088 acl_verify_csa(uschar *domain)
1092 int priority, weight, port;
1099 /* Work out the domain we are using for the CSA lookup. The default is the
1100 client's HELO domain. If the client has not said HELO, use its IP address
1101 instead. If it's a local client (exim -bs), CSA isn't applicable. */
1103 while (isspace(*domain) && *domain != '\0') ++domain;
1104 if (*domain == '\0') domain = sender_helo_name;
1105 if (domain == NULL) domain = sender_host_address;
1106 if (sender_host_address == NULL) return CSA_UNKNOWN;
1108 /* If we have an address literal, strip off the framing ready for turning it
1109 into a domain. The framing consists of matched square brackets possibly
1110 containing a keyword and a colon before the actual IP address. */
1112 if (domain[0] == '[')
1114 uschar *start = Ustrchr(domain, ':');
1115 if (start == NULL) start = domain;
1116 domain = string_copyn(start + 1, Ustrlen(start) - 2);
1119 /* Turn domains that look like bare IP addresses into domains in the reverse
1120 DNS. This code also deals with address literals and $sender_host_address. It's
1121 not quite kosher to treat bare domains such as EHLO 192.0.2.57 the same as
1122 address literals, but it's probably the most friendly thing to do. This is an
1123 extension to CSA, so we allow it to be turned off for proper conformance. */
1125 if (string_is_ip_address(domain, NULL))
1127 if (!dns_csa_use_reverse) return CSA_UNKNOWN;
1128 dns_build_reverse(domain, target);
1132 /* Find out if we've already done the CSA check for this domain. If we have,
1133 return the same result again. Otherwise build a new cached result structure
1134 for this domain. The name is filled in now, and the value is filled in when
1135 we return from this function. */
1137 t = tree_search(csa_cache, domain);
1138 if (t != NULL) return t->data.val;
1140 t = store_get_perm(sizeof(tree_node) + Ustrlen(domain));
1141 Ustrcpy(t->name, domain);
1142 (void)tree_insertnode(&csa_cache, t);
1144 /* Now we are ready to do the actual DNS lookup(s). */
1146 switch (dns_special_lookup(&dnsa, domain, T_CSA, &found))
1148 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1151 return t->data.val = CSA_DEFER_SRV;
1153 /* If we found nothing, the client's authorization is unknown. */
1157 return t->data.val = CSA_UNKNOWN;
1159 /* We got something! Go on to look at the reply in more detail. */
1165 /* Scan the reply for well-formed CSA SRV records. */
1167 for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS);
1169 rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT))
1171 if (rr->type != T_SRV) continue;
1173 /* Extract the numerical SRV fields (p is incremented) */
1176 GETSHORT(priority, p);
1177 GETSHORT(weight, p);
1181 debug_printf("CSA priority=%d weight=%d port=%d\n", priority, weight, port);
1183 /* Check the CSA version number */
1185 if (priority != 1) continue;
1187 /* If the domain does not have a CSA SRV record of its own (i.e. the domain
1188 found by dns_special_lookup() is a parent of the one we asked for), we check
1189 the subdomain assertions in the port field. At the moment there's only one
1190 assertion: legitimate SMTP clients are all explicitly authorized with CSA
1191 SRV records of their own. */
1193 if (found != domain)
1196 return t->data.val = CSA_FAIL_EXPLICIT;
1198 return t->data.val = CSA_UNKNOWN;
1201 /* This CSA SRV record refers directly to our domain, so we check the value
1202 in the weight field to work out the domain's authorization. 0 and 1 are
1203 unauthorized; 3 means the client is authorized but we can't check the IP
1204 address in order to authenticate it, so we treat it as unknown; values
1205 greater than 3 are undefined. */
1207 if (weight < 2) return t->data.val = CSA_FAIL_DOMAIN;
1209 if (weight > 2) continue;
1211 /* Weight == 2, which means the domain is authorized. We must check that the
1212 client's IP address is listed as one of the SRV target addresses. Save the
1213 target hostname then break to scan the additional data for its addresses. */
1215 (void)dn_expand(dnsa.answer, dnsa.answer + dnsa.answerlen, p,
1216 (DN_EXPAND_ARG4_TYPE)target, sizeof(target));
1218 DEBUG(D_acl) debug_printf("CSA target is %s\n", target);
1223 /* If we didn't break the loop then no appropriate records were found. */
1225 if (rr == NULL) return t->data.val = CSA_UNKNOWN;
1227 /* Do not check addresses if the target is ".", in accordance with RFC 2782.
1228 A target of "." indicates there are no valid addresses, so the client cannot
1229 be authorized. (This is an odd configuration because weight=2 target=. is
1230 equivalent to weight=1, but we check for it in order to keep load off the
1231 root name servers.) Note that dn_expand() turns "." into "". */
1233 if (Ustrcmp(target, "") == 0) return t->data.val = CSA_FAIL_NOADDR;
1235 /* Scan the additional section of the CSA SRV reply for addresses belonging
1236 to the target. If the name server didn't return any additional data (e.g.
1237 because it does not fully support SRV records), we need to do another lookup
1238 to obtain the target addresses; otherwise we have a definitive result. */
1240 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ADDITIONAL, target);
1241 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1243 /* The DNS lookup type corresponds to the IP version used by the client. */
1246 if (Ustrchr(sender_host_address, ':') != NULL)
1249 #endif /* HAVE_IPV6 */
1253 #if HAVE_IPV6 && defined(SUPPORT_A6)
1257 switch (dns_lookup(&dnsa, target, type, NULL))
1259 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1262 return t->data.val = CSA_DEFER_ADDR;
1264 /* If the query succeeded, scan the addresses and return the result. */
1267 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ANSWERS, target);
1268 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1269 /* else fall through */
1271 /* If the target has no IP addresses, the client cannot have an authorized
1272 IP address. However, if the target site uses A6 records (not AAAA records)
1273 we have to do yet another lookup in order to check them. */
1278 #if HAVE_IPV6 && defined(SUPPORT_A6)
1279 if (type == T_AAAA) { type = T_A6; goto DNS_LOOKUP_AGAIN; }
1282 return t->data.val = CSA_FAIL_NOADDR;
1288 /*************************************************
1289 * Handle verification (address & other) *
1290 *************************************************/
1292 /* This function implements the "verify" condition. It is called when
1293 encountered in any ACL, because some tests are almost always permitted. Some
1294 just don't make sense, and always fail (for example, an attempt to test a host
1295 lookup for a non-TCP/IP message). Others are restricted to certain ACLs.
1298 where where called from
1299 addr the recipient address that the ACL is handling, or NULL
1300 arg the argument of "verify"
1301 user_msgptr pointer for user message
1302 log_msgptr pointer for log message
1303 basic_errno where to put verify errno
1305 Returns: OK verification condition succeeded
1306 FAIL verification failed
1307 DEFER there was a problem verifying
1312 acl_verify(int where, address_item *addr, uschar *arg,
1313 uschar **user_msgptr, uschar **log_msgptr, int *basic_errno)
1317 int callout_overall = -1;
1318 int callout_connect = -1;
1319 int verify_options = 0;
1321 BOOL verify_header_sender = FALSE;
1322 BOOL defer_ok = FALSE;
1323 BOOL callout_defer_ok = FALSE;
1324 BOOL no_details = FALSE;
1325 address_item *sender_vaddr = NULL;
1326 uschar *verify_sender_address = NULL;
1327 uschar *pm_mailfrom = NULL;
1328 uschar *se_mailfrom = NULL;
1330 /* Some of the verify items have slash-separated options; some do not. Diagnose
1331 an error if options are given for items that don't expect them. This code has
1332 now got very message. Refactoring to use a table would be a good idea one day.
1335 uschar *slash = Ustrchr(arg, '/');
1337 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
1339 if (ss == NULL) goto BAD_VERIFY;
1341 /* Handle name/address consistency verification in a separate function. */
1343 if (strcmpic(ss, US"reverse_host_lookup") == 0)
1345 if (slash != NULL) goto NO_OPTIONS;
1346 if (sender_host_address == NULL) return OK;
1347 return acl_verify_reverse(user_msgptr, log_msgptr);
1350 /* TLS certificate verification is done at STARTTLS time; here we just
1351 test whether it was successful or not. (This is for optional verification; for
1352 mandatory verification, the connection doesn't last this long.) */
1354 if (strcmpic(ss, US"certificate") == 0)
1356 if (slash != NULL) goto NO_OPTIONS;
1357 if (tls_certificate_verified) return OK;
1358 *user_msgptr = US"no verified certificate";
1362 /* We can test the result of optional HELO verification */
1364 if (strcmpic(ss, US"helo") == 0)
1366 if (slash != NULL) goto NO_OPTIONS;
1367 return helo_verified? OK : FAIL;
1370 /* Do Client SMTP Authorization checks in a separate function, and turn the
1371 result code into user-friendly strings. */
1373 if (strcmpic(ss, US"csa") == 0)
1375 rc = acl_verify_csa(list);
1376 *log_msgptr = *user_msgptr = string_sprintf("client SMTP authorization %s",
1377 csa_reason_string[rc]);
1378 csa_status = csa_status_string[rc];
1379 DEBUG(D_acl) debug_printf("CSA result %s\n", csa_status);
1380 return csa_return_code[rc];
1383 /* Check that all relevant header lines have the correct syntax. If there is
1384 a syntax error, we return details of the error to the sender if configured to
1385 send out full details. (But a "message" setting on the ACL can override, as
1388 if (strcmpic(ss, US"header_syntax") == 0)
1390 if (slash != NULL) goto NO_OPTIONS;
1391 if (where != ACL_WHERE_DATA && where != ACL_WHERE_NOTSMTP)
1393 *log_msgptr = string_sprintf("cannot check header contents in ACL for %s "
1394 "(only possible in ACL for DATA)", acl_wherenames[where]);
1397 rc = verify_check_headers(log_msgptr);
1398 if (rc != OK && smtp_return_error_details && *log_msgptr != NULL)
1399 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1404 /* The remaining verification tests check recipient and sender addresses,
1405 either from the envelope or from the header. There are a number of
1406 slash-separated options that are common to all of them. */
1409 /* Check that there is at least one verifiable sender address in the relevant
1410 header lines. This can be followed by callout and defer options, just like
1411 sender and recipient. */
1413 if (strcmpic(ss, US"header_sender") == 0)
1415 if (where != ACL_WHERE_DATA && where != ACL_WHERE_NOTSMTP)
1417 *log_msgptr = string_sprintf("cannot check header contents in ACL for %s "
1418 "(only possible in ACL for DATA)", acl_wherenames[where]);
1421 verify_header_sender = TRUE;
1424 /* Otherwise, first item in verify argument must be "sender" or "recipient".
1425 In the case of a sender, this can optionally be followed by an address to use
1426 in place of the actual sender (rare special-case requirement). */
1428 else if (strncmpic(ss, US"sender", 6) == 0)
1431 if (where > ACL_WHERE_NOTSMTP)
1433 *log_msgptr = string_sprintf("cannot verify sender in ACL for %s "
1434 "(only possible for MAIL, RCPT, PREDATA, or DATA)",
1435 acl_wherenames[where]);
1439 verify_sender_address = sender_address;
1442 while (isspace(*s)) s++;
1443 if (*s++ != '=') goto BAD_VERIFY;
1444 while (isspace(*s)) s++;
1445 verify_sender_address = string_copy(s);
1450 if (strcmpic(ss, US"recipient") != 0) goto BAD_VERIFY;
1453 *log_msgptr = string_sprintf("cannot verify recipient in ACL for %s "
1454 "(only possible for RCPT)", acl_wherenames[where]);
1459 /* Remaining items are optional; they apply to sender and recipient
1460 verification, including "header sender" verification. */
1462 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size))
1465 if (strcmpic(ss, US"defer_ok") == 0) defer_ok = TRUE;
1466 else if (strcmpic(ss, US"no_details") == 0) no_details = TRUE;
1468 /* These two old options are left for backwards compatibility */
1470 else if (strcmpic(ss, US"callout_defer_ok") == 0)
1472 callout_defer_ok = TRUE;
1473 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1476 else if (strcmpic(ss, US"check_postmaster") == 0)
1479 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1482 /* The callout option has a number of sub-options, comma separated */
1484 else if (strncmpic(ss, US"callout", 7) == 0)
1486 callout = CALLOUT_TIMEOUT_DEFAULT;
1490 while (isspace(*ss)) ss++;
1496 while (isspace(*ss)) ss++;
1498 /* This callout option handling code has become a mess as new options
1499 have been added in an ad hoc manner. It should be tidied up into some
1500 kind of table-driven thing. */
1502 while ((opt = string_nextinlist(&ss, &optsep, buffer, sizeof(buffer)))
1505 if (strcmpic(opt, US"defer_ok") == 0) callout_defer_ok = TRUE;
1506 else if (strcmpic(opt, US"no_cache") == 0)
1507 verify_options |= vopt_callout_no_cache;
1508 else if (strcmpic(opt, US"random") == 0)
1509 verify_options |= vopt_callout_random;
1510 else if (strcmpic(opt, US"use_sender") == 0)
1511 verify_options |= vopt_callout_recipsender;
1512 else if (strcmpic(opt, US"use_postmaster") == 0)
1513 verify_options |= vopt_callout_recippmaster;
1514 else if (strcmpic(opt, US"postmaster") == 0) pm_mailfrom = US"";
1516 else if (strncmpic(opt, US"mailfrom", 8) == 0)
1518 if (!verify_header_sender)
1520 *log_msgptr = string_sprintf("\"mailfrom\" is allowed as a "
1521 "callout option only for verify=header_sender (detected in ACL "
1522 "condition \"%s\")", arg);
1526 while (isspace(*opt)) opt++;
1529 *log_msgptr = string_sprintf("'=' expected after "
1530 "\"mailfrom\" in ACL condition \"%s\"", arg);
1533 while (isspace(*opt)) opt++;
1534 se_mailfrom = string_copy(opt);
1537 else if (strncmpic(opt, US"postmaster_mailfrom", 19) == 0)
1540 while (isspace(*opt)) opt++;
1543 *log_msgptr = string_sprintf("'=' expected after "
1544 "\"postmaster_mailfrom\" in ACL condition \"%s\"", arg);
1547 while (isspace(*opt)) opt++;
1548 pm_mailfrom = string_copy(opt);
1551 else if (strncmpic(opt, US"maxwait", 7) == 0)
1554 while (isspace(*opt)) opt++;
1557 *log_msgptr = string_sprintf("'=' expected after \"maxwait\" in "
1558 "ACL condition \"%s\"", arg);
1561 while (isspace(*opt)) opt++;
1562 callout_overall = readconf_readtime(opt, 0, FALSE);
1563 if (callout_overall < 0)
1565 *log_msgptr = string_sprintf("bad time value in ACL condition "
1566 "\"verify %s\"", arg);
1570 else if (strncmpic(opt, US"connect", 7) == 0)
1573 while (isspace(*opt)) opt++;
1576 *log_msgptr = string_sprintf("'=' expected after "
1577 "\"callout_overaall\" in ACL condition \"%s\"", arg);
1580 while (isspace(*opt)) opt++;
1581 callout_connect = readconf_readtime(opt, 0, FALSE);
1582 if (callout_connect < 0)
1584 *log_msgptr = string_sprintf("bad time value in ACL condition "
1585 "\"verify %s\"", arg);
1589 else /* Plain time is callout connect/command timeout */
1591 callout = readconf_readtime(opt, 0, FALSE);
1594 *log_msgptr = string_sprintf("bad time value in ACL condition "
1595 "\"verify %s\"", arg);
1603 *log_msgptr = string_sprintf("'=' expected after \"callout\" in "
1604 "ACL condition \"%s\"", arg);
1610 /* Option not recognized */
1614 *log_msgptr = string_sprintf("unknown option \"%s\" in ACL "
1615 "condition \"verify %s\"", ss, arg);
1620 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster)) ==
1621 (vopt_callout_recipsender|vopt_callout_recippmaster))
1623 *log_msgptr = US"only one of use_sender and use_postmaster can be set "
1624 "for a recipient callout";
1628 /* Handle sender-in-header verification. Default the user message to the log
1629 message if giving out verification details. */
1631 if (verify_header_sender)
1634 rc = verify_check_header_address(user_msgptr, log_msgptr, callout,
1635 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, verify_options,
1639 *basic_errno = verrno;
1640 if (smtp_return_error_details)
1642 if (*user_msgptr == NULL && *log_msgptr != NULL)
1643 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1644 if (rc == DEFER) acl_temp_details = TRUE;
1649 /* Handle a sender address. The default is to verify *the* sender address, but
1650 optionally a different address can be given, for special requirements. If the
1651 address is empty, we are dealing with a bounce message that has no sender, so
1652 we cannot do any checking. If the real sender address gets rewritten during
1653 verification (e.g. DNS widening), set the flag to stop it being rewritten again
1654 during message reception.
1656 A list of verified "sender" addresses is kept to try to avoid doing to much
1657 work repetitively when there are multiple recipients in a message and they all
1658 require sender verification. However, when callouts are involved, it gets too
1659 complicated because different recipients may require different callout options.
1660 Therefore, we always do a full sender verify when any kind of callout is
1661 specified. Caching elsewhere, for instance in the DNS resolver and in the
1662 callout handling, should ensure that this is not terribly inefficient. */
1664 else if (verify_sender_address != NULL)
1666 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster))
1669 *log_msgptr = US"use_sender or use_postmaster cannot be used for a "
1670 "sender verify callout";
1674 sender_vaddr = verify_checked_sender(verify_sender_address);
1675 if (sender_vaddr != NULL && /* Previously checked */
1676 callout <= 0) /* No callout needed this time */
1678 /* If the "routed" flag is set, it means that routing worked before, so
1679 this check can give OK (the saved return code value, if set, belongs to a
1680 callout that was done previously). If the "routed" flag is not set, routing
1681 must have failed, so we use the saved return code. */
1683 if (testflag(sender_vaddr, af_verify_routed)) rc = OK; else
1685 rc = sender_vaddr->special_action;
1686 *basic_errno = sender_vaddr->basic_errno;
1688 HDEBUG(D_acl) debug_printf("using cached sender verify result\n");
1691 /* Do a new verification, and cache the result. The cache is used to avoid
1692 verifying the sender multiple times for multiple RCPTs when callouts are not
1693 specified (see comments above).
1695 The cache is also used on failure to give details in response to the first
1696 RCPT that gets bounced for this reason. However, this can be suppressed by
1697 the no_details option, which sets the flag that says "this detail has already
1698 been sent". The cache normally contains just one address, but there may be
1699 more in esoteric circumstances. */
1704 uschar *save_address_data = deliver_address_data;
1706 sender_vaddr = deliver_make_addr(verify_sender_address, TRUE);
1707 if (no_details) setflag(sender_vaddr, af_sverify_told);
1708 if (verify_sender_address[0] != 0)
1710 /* If this is the real sender address, save the unrewritten version
1711 for use later in receive. Otherwise, set a flag so that rewriting the
1712 sender in verify_address() does not update sender_address. */
1714 if (verify_sender_address == sender_address)
1715 sender_address_unrewritten = sender_address;
1717 verify_options |= vopt_fake_sender;
1719 /* The recipient, qualify, and expn options are never set in
1722 rc = verify_address(sender_vaddr, NULL, verify_options, callout,
1723 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, &routed);
1725 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
1729 if (Ustrcmp(sender_vaddr->address, verify_sender_address) != 0)
1731 DEBUG(D_acl) debug_printf("sender %s verified ok as %s\n",
1732 verify_sender_address, sender_vaddr->address);
1736 DEBUG(D_acl) debug_printf("sender %s verified ok\n",
1737 verify_sender_address);
1740 else *basic_errno = sender_vaddr->basic_errno;
1742 else rc = OK; /* Null sender */
1744 /* Cache the result code */
1746 if (routed) setflag(sender_vaddr, af_verify_routed);
1747 if (callout > 0) setflag(sender_vaddr, af_verify_callout);
1748 sender_vaddr->special_action = rc;
1749 sender_vaddr->next = sender_verified_list;
1750 sender_verified_list = sender_vaddr;
1752 /* Restore the recipient address data, which might have been clobbered by
1753 the sender verification. */
1755 deliver_address_data = save_address_data;
1758 /* Put the sender address_data value into $sender_address_data */
1760 sender_address_data = sender_vaddr->p.address_data;
1763 /* A recipient address just gets a straightforward verify; again we must handle
1764 the DEFER overrides. */
1770 /* We must use a copy of the address for verification, because it might
1774 rc = verify_address(&addr2, NULL, verify_options|vopt_is_recipient, callout,
1775 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, NULL);
1776 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
1778 *log_msgptr = addr2.message;
1779 *user_msgptr = (addr2.user_message != NULL)?
1780 addr2.user_message : addr2.message;
1781 *basic_errno = addr2.basic_errno;
1783 /* Make $address_data visible */
1784 deliver_address_data = addr2.p.address_data;
1787 /* We have a result from the relevant test. Handle defer overrides first. */
1789 if (rc == DEFER && (defer_ok ||
1790 (callout_defer_ok && *basic_errno == ERRNO_CALLOUTDEFER)))
1792 HDEBUG(D_acl) debug_printf("verify defer overridden by %s\n",
1793 defer_ok? "defer_ok" : "callout_defer_ok");
1797 /* If we've failed a sender, set up a recipient message, and point
1798 sender_verified_failed to the address item that actually failed. */
1800 if (rc != OK && verify_sender_address != NULL)
1804 *log_msgptr = *user_msgptr = US"Sender verify failed";
1806 else if (*basic_errno != ERRNO_CALLOUTDEFER)
1808 *log_msgptr = *user_msgptr = US"Could not complete sender verify";
1812 *log_msgptr = US"Could not complete sender verify callout";
1813 *user_msgptr = smtp_return_error_details? sender_vaddr->user_message :
1817 sender_verified_failed = sender_vaddr;
1820 /* Verifying an address messes up the values of $domain and $local_part,
1821 so reset them before returning if this is a RCPT ACL. */
1825 deliver_domain = addr->domain;
1826 deliver_localpart = addr->local_part;
1830 /* Syntax errors in the verify argument come here. */
1833 *log_msgptr = string_sprintf("expected \"sender[=address]\", \"recipient\", "
1834 "\"helo\", \"header_syntax\", \"header_sender\" or "
1835 "\"reverse_host_lookup\" at start of ACL condition "
1836 "\"verify %s\"", arg);
1839 /* Options supplied when not allowed come here */
1842 *log_msgptr = string_sprintf("unexpected '/' found in \"%s\" "
1843 "(this verify item has no options)", arg);
1850 /*************************************************
1851 * Check argument for control= modifier *
1852 *************************************************/
1854 /* Called from acl_check_condition() below
1857 arg the argument string for control=
1858 pptr set to point to the terminating character
1859 where which ACL we are in
1860 log_msgptr for error messages
1862 Returns: CONTROL_xxx value
1866 decode_control(uschar *arg, uschar **pptr, int where, uschar **log_msgptr)
1871 for (d = controls_list;
1872 d < controls_list + sizeof(controls_list)/sizeof(control_def);
1875 len = Ustrlen(d->name);
1876 if (Ustrncmp(d->name, arg, len) == 0) break;
1879 if (d >= controls_list + sizeof(controls_list)/sizeof(control_def) ||
1880 (arg[len] != 0 && (!d->has_option || arg[len] != '/')))
1882 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
1883 return CONTROL_ERROR;
1892 /*************************************************
1893 * Handle rate limiting *
1894 *************************************************/
1896 /* Called by acl_check_condition() below to calculate the result
1897 of the ACL ratelimit condition.
1899 Note that the return value might be slightly unexpected: if the
1900 sender's rate is above the limit then the result is OK. This is
1901 similar to the dnslists condition, and is so that you can write
1902 ACL clauses like: defer ratelimit = 15 / 1h
1905 arg the option string for ratelimit=
1906 log_msgptr for error messages
1908 Returns: OK - Sender's rate is above limit
1909 FAIL - Sender's rate is below limit
1910 DEFER - Problem opening ratelimit database
1911 ERROR - Syntax error in options.
1915 acl_ratelimit(uschar *arg, uschar **log_msgptr)
1917 double limit, period;
1918 uschar *ss, *key = arg;
1920 BOOL have_key = FALSE, leaky = FALSE, strict = FALSE;
1921 BOOL per_byte = FALSE, per_cmd = FALSE, per_conn = FALSE, per_mail = FALSE;
1923 tree_node **anchor, *t;
1924 open_db dbblock, *dbm;
1925 dbdata_ratelimit *dbd;
1928 /* Parse the first two options and record their values in expansion
1929 variables. These variables allow the configuration to have informative
1930 error messages based on rate limits obtained from a table lookup. */
1932 /* First is the maximum number of messages per period and maximum burst
1933 size, which must be greater than or equal to zero. Zero is useful for
1934 rate measurement as opposed to rate limiting. */
1936 sender_rate_limit = string_nextinlist(&arg, &sep, NULL, 0);
1937 if (sender_rate_limit == NULL)
1941 limit = Ustrtod(sender_rate_limit, &ss);
1942 if (tolower(*ss) == 'k') { limit *= 1024.0; ss++; }
1943 else if (tolower(*ss) == 'm') { limit *= 1024.0*1024.0; ss++; }
1944 else if (tolower(*ss) == 'g') { limit *= 1024.0*1024.0*1024.0; ss++; }
1946 if (limit < 0.0 || *ss != 0)
1948 *log_msgptr = string_sprintf("syntax error in argument for "
1949 "\"ratelimit\" condition: \"%s\" is not a positive number",
1954 /* Second is the rate measurement period and exponential smoothing time
1955 constant. This must be strictly greater than zero, because zero leads to
1956 run-time division errors. */
1958 sender_rate_period = string_nextinlist(&arg, &sep, NULL, 0);
1959 if (sender_rate_period == NULL) period = -1.0;
1960 else period = readconf_readtime(sender_rate_period, 0, FALSE);
1963 *log_msgptr = string_sprintf("syntax error in argument for "
1964 "\"ratelimit\" condition: \"%s\" is not a time value",
1965 sender_rate_period);
1969 /* Parse the other options. Should we check if the per_* options are being
1970 used in ACLs where they don't make sense, e.g. per_mail in the connect ACL? */
1972 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
1975 if (strcmpic(ss, US"leaky") == 0) leaky = TRUE;
1976 else if (strcmpic(ss, US"strict") == 0) strict = TRUE;
1977 else if (strcmpic(ss, US"per_byte") == 0) per_byte = TRUE;
1978 else if (strcmpic(ss, US"per_cmd") == 0) per_cmd = TRUE;
1979 else if (strcmpic(ss, US"per_conn") == 0) per_conn = TRUE;
1980 else if (strcmpic(ss, US"per_mail") == 0) per_mail = TRUE;
1981 else if (strcmpic(ss, US"per_rcpt") == 0) per_cmd = TRUE; /* alias */
1982 else have_key = TRUE;
1984 if (leaky + strict > 1 || per_byte + per_cmd + per_conn + per_mail > 1)
1986 *log_msgptr = US"conflicting options for \"ratelimit\" condition";
1990 /* Default option values */
1991 if (!strict) leaky = TRUE;
1992 if (!per_byte && !per_cmd && !per_conn) per_mail = TRUE;
1994 /* We use the whole of the argument list as the lookup key, because it doesn't
1995 make sense to use the same stored data if any of the arguments are different.
1996 If there is no explicit key, use the sender_host_address. If there is no
1997 sender_host_address (e.g. -bs or acl_not_smtp) then we simply omit it. */
1999 if (!have_key && sender_host_address != NULL)
2000 key = string_sprintf("%s / %s", key, sender_host_address);
2002 HDEBUG(D_acl) debug_printf("ratelimit condition limit=%.0f period=%.0f key=%s\n",
2003 limit, period, key);
2005 /* If we are dealing with rate limits per connection, per message, or per byte,
2006 see if we have already computed the rate by looking in the relevant tree. For
2007 per-connection rate limiting, store tree nodes and dbdata in the permanent pool
2008 so that they survive across resets. */
2011 old_pool = store_pool;
2015 anchor = &ratelimiters_conn;
2016 store_pool = POOL_PERM;
2018 if (per_mail || per_byte)
2019 anchor = &ratelimiters_mail;
2021 if (anchor != NULL && (t = tree_search(*anchor, key)) != NULL)
2024 /* The following few lines duplicate some of the code below. */
2025 if (dbd->rate < limit) rc = FAIL;
2027 store_pool = old_pool;
2028 sender_rate = string_sprintf("%.1f", dbd->rate);
2030 debug_printf("ratelimit found pre-computed rate %s\n", sender_rate);
2034 /* We aren't using a pre-computed rate, so get a previously recorded
2035 rate from the database, update it, and write it back. If there's no
2036 previous rate for this key, create one. */
2038 dbm = dbfn_open(US"ratelimit", O_RDWR, &dbblock, TRUE);
2041 store_pool = old_pool;
2043 HDEBUG(D_acl) debug_printf("ratelimit database not available\n");
2044 *log_msgptr = US"ratelimit database not available";
2047 dbd = dbfn_read(dbm, key);
2049 gettimeofday(&tv, NULL);
2053 HDEBUG(D_acl) debug_printf("ratelimit initializing new key's data\n");
2054 dbd = store_get(sizeof(dbdata_ratelimit));
2055 dbd->time_stamp = tv.tv_sec;
2056 dbd->time_usec = tv.tv_usec;
2061 /* The smoothed rate is computed using an exponentially weighted moving
2062 average adjusted for variable sampling intervals. The standard EWMA for
2063 a fixed sampling interval is: f'(t) = (1 - a) * f(t) + a * f'(t - 1)
2064 where f() is the measured value and f'() is the smoothed value.
2066 Old data decays out of the smoothed value exponentially, such that data n
2067 samples old is multiplied by a^n. The exponential decay time constant p
2068 is defined such that data p samples old is multiplied by 1/e, which means
2069 that a = exp(-1/p). We can maintain the same time constant for a variable
2070 sampling interval i by using a = exp(-i/p).
2072 The rate we are measuring is messages per period, suitable for directly
2073 comparing with the limit. The average rate between now and the previous
2074 message is period / interval, which we feed into the EWMA as the sample.
2076 It turns out that the number of messages required for the smoothed rate
2077 to reach the limit when they are sent in a burst is equal to the limit.
2078 This can be seen by analysing the value of the smoothed rate after N
2079 messages sent at even intervals. Let k = (1 - a) * p/i
2081 rate_1 = (1 - a) * p/i + a * rate_0
2083 rate_2 = k + a * rate_1
2084 = k + a * k + a^2 * rate_0
2085 rate_3 = k + a * k + a^2 * k + a^3 * rate_0
2086 rate_N = rate_0 * a^N + k * SUM(x=0..N-1)(a^x)
2087 = rate_0 * a^N + k * (1 - a^N) / (1 - a)
2088 = rate_0 * a^N + p/i * (1 - a^N)
2090 When N is large, a^N -> 0 so rate_N -> p/i as desired.
2092 rate_N = p/i + (rate_0 - p/i) * a^N
2093 a^N = (rate_N - p/i) / (rate_0 - p/i)
2094 N * -i/p = log((rate_N - p/i) / (rate_0 - p/i))
2095 N = p/i * log((rate_0 - p/i) / (rate_N - p/i))
2097 Numerical analysis of the above equation, setting the computed rate to
2098 increase from rate_0 = 0 to rate_N = limit, shows that for large sending
2099 rates, p/i, the number of messages N = limit. So limit serves as both the
2100 maximum rate measured in messages per period, and the maximum number of
2101 messages that can be sent in a fast burst. */
2103 double this_time = (double)tv.tv_sec
2104 + (double)tv.tv_usec / 1000000.0;
2105 double prev_time = (double)dbd->time_stamp
2106 + (double)dbd->time_usec / 1000000.0;
2107 double interval = this_time - prev_time;
2109 double i_over_p = interval / period;
2110 double a = exp(-i_over_p);
2112 /* We must avoid division by zero, and deal gracefully with the clock going
2113 backwards. If we blunder ahead when time is in reverse then the computed
2114 rate will become bogusly huge. Clamp i/p to a very small number instead. */
2116 if (i_over_p <= 0.0) i_over_p = 1e-9;
2118 dbd->time_stamp = tv.tv_sec;
2119 dbd->time_usec = tv.tv_usec;
2121 /* If we are measuring the rate in bytes per period, multiply the
2122 measured rate by the message size. If we don't know the message size
2123 then it's safe to just use a value of zero and let the recorded rate
2124 decay as if nothing happened. */
2127 dbd->rate = (message_size < 0 ? 0.0 : (double)message_size)
2128 * (1 - a) / i_over_p + a * dbd->rate;
2130 dbd->rate = (1 - a) / i_over_p + a * dbd->rate;
2133 /* Clients sending at the limit are considered to be over the limit. This
2134 matters for edge cases such the first message sent by a client (which gets
2135 the initial rate of 0.0) when the rate limit is zero (i.e. the client should
2136 be completely blocked). */
2138 if (dbd->rate < limit) rc = FAIL;
2141 /* Update the state if the rate is low or if we are being strict. If we
2142 are in leaky mode and the sender's rate is too high, we do not update
2143 the recorded rate in order to avoid an over-aggressive sender's retry
2144 rate preventing them from getting any email through. */
2146 if (rc == FAIL || !leaky)
2147 dbfn_write(dbm, key, dbd, sizeof(dbdata_ratelimit));
2150 /* Store the result in the tree for future reference, if necessary. */
2154 t = store_get(sizeof(tree_node) + Ustrlen(key));
2156 Ustrcpy(t->name, key);
2157 (void)tree_insertnode(anchor, t);
2160 /* We create the formatted version of the sender's rate very late in
2161 order to ensure that it is done using the correct storage pool. */
2163 store_pool = old_pool;
2164 sender_rate = string_sprintf("%.1f", dbd->rate);
2167 debug_printf("ratelimit computed rate %s\n", sender_rate);
2174 /*************************************************
2175 * Handle conditions/modifiers on an ACL item *
2176 *************************************************/
2178 /* Called from acl_check() below.
2182 cb ACL condition block - if NULL, result is OK
2183 where where called from
2184 addr the address being checked for RCPT, or NULL
2185 level the nesting level
2186 epp pointer to pass back TRUE if "endpass" encountered
2187 (applies only to "accept" and "discard")
2188 user_msgptr user message pointer
2189 log_msgptr log message pointer
2190 basic_errno pointer to where to put verify error
2192 Returns: OK - all conditions are met
2193 DISCARD - an "acl" condition returned DISCARD - only allowed
2194 for "accept" or "discard" verbs
2195 FAIL - at least one condition fails
2196 FAIL_DROP - an "acl" condition returned FAIL_DROP
2197 DEFER - can't tell at the moment (typically, lookup defer,
2198 but can be temporary callout problem)
2199 ERROR - ERROR from nested ACL or expansion failure or other
2204 acl_check_condition(int verb, acl_condition_block *cb, int where,
2205 address_item *addr, int level, BOOL *epp, uschar **user_msgptr,
2206 uschar **log_msgptr, int *basic_errno)
2208 uschar *user_message = NULL;
2209 uschar *log_message = NULL;
2212 #ifdef WITH_CONTENT_SCAN
2216 for (; cb != NULL; cb = cb->next)
2221 /* The message and log_message items set up messages to be used in
2222 case of rejection. They are expanded later. */
2224 if (cb->type == ACLC_MESSAGE)
2226 user_message = cb->arg;
2230 if (cb->type == ACLC_LOG_MESSAGE)
2232 log_message = cb->arg;
2236 /* The endpass "condition" just sets a flag to show it occurred. This is
2237 checked at compile time to be on an "accept" or "discard" item. */
2239 if (cb->type == ACLC_ENDPASS)
2245 /* For other conditions and modifiers, the argument is expanded now for some
2246 of them, but not for all, because expansion happens down in some lower level
2247 checking functions in some cases. */
2249 if (cond_expand_at_top[cb->type])
2251 arg = expand_string(cb->arg);
2254 if (expand_string_forcedfail) continue;
2255 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s",
2256 cb->arg, expand_string_message);
2257 return search_find_defer? DEFER : ERROR;
2262 /* Show condition, and expanded condition if it's different */
2267 debug_printf("check %s%s %n",
2268 (!cond_modifiers[cb->type] && cb->u.negated)? "!":"",
2269 conditions[cb->type], &lhswidth);
2271 if (cb->type == ACLC_SET)
2273 int n = cb->u.varnumber;
2274 int t = (n < ACL_C_MAX)? 'c' : 'm';
2275 if (n >= ACL_C_MAX) n -= ACL_C_MAX;
2276 debug_printf("acl_%c%d ", t, n);
2280 debug_printf("= %s\n", cb->arg);
2283 debug_printf("%.*s= %s\n", lhswidth,
2287 /* Check that this condition makes sense at this time */
2289 if ((cond_forbids[cb->type] & (1 << where)) != 0)
2291 *log_msgptr = string_sprintf("cannot %s %s condition in %s ACL",
2292 cond_modifiers[cb->type]? "use" : "test",
2293 conditions[cb->type], acl_wherenames[where]);
2297 /* Run the appropriate test for each condition, or take the appropriate
2298 action for the remaining modifiers. */
2302 /* A nested ACL that returns "discard" makes sense only for an "accept" or
2306 rc = acl_check_internal(where, addr, arg, level+1, user_msgptr, log_msgptr);
2307 if (rc == DISCARD && verb != ACL_ACCEPT && verb != ACL_DISCARD)
2309 *log_msgptr = string_sprintf("nested ACL returned \"discard\" for "
2310 "\"%s\" command (only allowed with \"accept\" or \"discard\")",
2316 case ACLC_AUTHENTICATED:
2317 rc = (sender_host_authenticated == NULL)? FAIL :
2318 match_isinlist(sender_host_authenticated, &arg, 0, NULL, NULL, MCL_STRING,
2322 #ifdef EXPERIMENTAL_BRIGHTMAIL
2323 case ACLC_BMI_OPTIN:
2325 int old_pool = store_pool;
2326 store_pool = POOL_PERM;
2327 bmi_current_optin = string_copy(arg);
2328 store_pool = old_pool;
2333 case ACLC_CONDITION:
2334 if (Ustrspn(arg, "0123456789") == Ustrlen(arg)) /* Digits, or empty */
2335 rc = (Uatoi(arg) == 0)? FAIL : OK;
2337 rc = (strcmpic(arg, US"no") == 0 ||
2338 strcmpic(arg, US"false") == 0)? FAIL :
2339 (strcmpic(arg, US"yes") == 0 ||
2340 strcmpic(arg, US"true") == 0)? OK : DEFER;
2342 *log_msgptr = string_sprintf("invalid \"condition\" value \"%s\"", arg);
2346 control_type = decode_control(arg, &p, where, log_msgptr);
2348 /* Check if this control makes sense at this time */
2350 if ((control_forbids[control_type] & (1 << where)) != 0)
2352 *log_msgptr = string_sprintf("cannot use \"control=%s\" in %s ACL",
2353 controls[control_type], acl_wherenames[where]);
2357 switch(control_type)
2359 #ifdef EXPERIMENTAL_BRIGHTMAIL
2360 case CONTROL_BMI_RUN:
2364 #ifdef EXPERIMENTAL_DOMAINKEYS
2365 case CONTROL_DK_VERIFY:
2372 case CONTROL_CASEFUL_LOCAL_PART:
2373 deliver_localpart = addr->cc_local_part;
2376 case CONTROL_CASELOWER_LOCAL_PART:
2377 deliver_localpart = addr->lc_local_part;
2380 case CONTROL_ENFORCE_SYNC:
2381 smtp_enforce_sync = TRUE;
2384 case CONTROL_NO_ENFORCE_SYNC:
2385 smtp_enforce_sync = FALSE;
2388 #ifdef WITH_CONTENT_SCAN
2389 case CONTROL_NO_MBOX_UNSPOOL:
2390 no_mbox_unspool = TRUE;
2394 case CONTROL_NO_MULTILINE:
2395 no_multiline_responses = TRUE;
2398 case CONTROL_FAKEDEFER:
2399 case CONTROL_FAKEREJECT:
2400 fake_response = (control_type == CONTROL_FAKEDEFER) ? DEFER : FAIL;
2404 while (*pp != 0) pp++;
2405 fake_response_text = expand_string(string_copyn(p+1, pp-p-1));
2410 /* Explicitly reset to default string */
2411 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).";
2415 case CONTROL_FREEZE:
2416 deliver_freeze = TRUE;
2417 deliver_frozen_at = time(NULL);
2420 case CONTROL_QUEUE_ONLY:
2421 queue_only_policy = TRUE;
2424 case CONTROL_SUBMISSION:
2425 originator_name = US"";
2426 submission_mode = TRUE;
2429 if (Ustrncmp(p, "/sender_retain", 14) == 0)
2432 active_local_sender_retain = TRUE;
2433 active_local_from_check = FALSE;
2435 else if (Ustrncmp(p, "/domain=", 8) == 0)
2438 while (*pp != 0 && *pp != '/') pp++;
2439 submission_domain = string_copyn(p+8, pp-p-8);
2442 else if (Ustrncmp(p, "/name=", 6) == 0)
2445 while (*pp != 0 && *pp != '/') pp++;
2446 originator_name = string_copy(parse_fix_phrase(p+6, pp-p-6,
2447 big_buffer, big_buffer_size));
2454 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
2461 #ifdef WITH_CONTENT_SCAN
2463 rc = mime_decode(&arg);
2469 int delay = readconf_readtime(arg, 0, FALSE);
2472 *log_msgptr = string_sprintf("syntax error in argument for \"delay\" "
2473 "modifier: \"%s\" is not a time value", arg);
2478 HDEBUG(D_acl) debug_printf("delay modifier requests %d-second delay\n",
2483 debug_printf("delay skipped in -bh checking mode\n");
2486 /* It appears to be impossible to detect that a TCP/IP connection has
2487 gone away without reading from it. This means that we cannot shorten
2488 the delay below if the client goes away, because we cannot discover
2489 that the client has closed its end of the connection. (The connection
2490 is actually in a half-closed state, waiting for the server to close its
2491 end.) It would be nice to be able to detect this state, so that the
2492 Exim process is not held up unnecessarily. However, it seems that we
2493 can't. The poll() function does not do the right thing, and in any case
2494 it is not always available.
2496 NOTE: If ever this state of affairs changes, remember that we may be
2497 dealing with stdin/stdout here, in addition to TCP/IP connections.
2498 Whatever is done must work in both cases. To detected the stdin/stdout
2499 case, check for smtp_in or smtp_out being NULL. */
2503 while (delay > 0) delay = sleep(delay);
2509 #ifdef WITH_OLD_DEMIME
2515 #ifdef EXPERIMENTAL_DOMAINKEYS
2516 case ACLC_DK_DOMAIN_SOURCE:
2517 if (dk_verify_block == NULL) { rc = FAIL; break; };
2518 /* check header source of domain against given string */
2519 switch (dk_verify_block->address_source) {
2520 case DK_EXIM_ADDRESS_FROM_FROM:
2521 rc = match_isinlist(US"from", &arg, 0, NULL,
2522 NULL, MCL_STRING, TRUE, NULL);
2524 case DK_EXIM_ADDRESS_FROM_SENDER:
2525 rc = match_isinlist(US"sender", &arg, 0, NULL,
2526 NULL, MCL_STRING, TRUE, NULL);
2528 case DK_EXIM_ADDRESS_NONE:
2529 rc = match_isinlist(US"none", &arg, 0, NULL,
2530 NULL, MCL_STRING, TRUE, NULL);
2534 case ACLC_DK_POLICY:
2535 if (dk_verify_block == NULL) { rc = FAIL; break; };
2536 /* check policy against given string, default FAIL */
2538 if (dk_verify_block->signsall)
2539 rc = match_isinlist(US"signsall", &arg, 0, NULL,
2540 NULL, MCL_STRING, TRUE, NULL);
2541 if (dk_verify_block->testing)
2542 rc = match_isinlist(US"testing", &arg, 0, NULL,
2543 NULL, MCL_STRING, TRUE, NULL);
2545 case ACLC_DK_SENDER_DOMAINS:
2546 if (dk_verify_block == NULL) { rc = FAIL; break; };
2547 if (dk_verify_block->domain != NULL)
2548 rc = match_isinlist(dk_verify_block->domain, &arg, 0, &domainlist_anchor,
2549 NULL, MCL_DOMAIN, TRUE, NULL);
2552 case ACLC_DK_SENDER_LOCAL_PARTS:
2553 if (dk_verify_block == NULL) { rc = FAIL; break; };
2554 if (dk_verify_block->local_part != NULL)
2555 rc = match_isinlist(dk_verify_block->local_part, &arg, 0, &localpartlist_anchor,
2556 NULL, MCL_LOCALPART, TRUE, NULL);
2559 case ACLC_DK_SENDERS:
2560 if (dk_verify_block == NULL) { rc = FAIL; break; };
2561 if (dk_verify_block->address != NULL)
2562 rc = match_address_list(dk_verify_block->address, TRUE, TRUE, &arg, NULL, -1, 0, NULL);
2565 case ACLC_DK_STATUS:
2566 if (dk_verify_block == NULL) { rc = FAIL; break; };
2567 if (dk_verify_block->result > 0) {
2568 switch(dk_verify_block->result) {
2569 case DK_EXIM_RESULT_BAD_FORMAT:
2570 rc = match_isinlist(US"bad format", &arg, 0, NULL,
2571 NULL, MCL_STRING, TRUE, NULL);
2573 case DK_EXIM_RESULT_NO_KEY:
2574 rc = match_isinlist(US"no key", &arg, 0, NULL,
2575 NULL, MCL_STRING, TRUE, NULL);
2577 case DK_EXIM_RESULT_NO_SIGNATURE:
2578 rc = match_isinlist(US"no signature", &arg, 0, NULL,
2579 NULL, MCL_STRING, TRUE, NULL);
2581 case DK_EXIM_RESULT_REVOKED:
2582 rc = match_isinlist(US"revoked", &arg, 0, NULL,
2583 NULL, MCL_STRING, TRUE, NULL);
2585 case DK_EXIM_RESULT_NON_PARTICIPANT:
2586 rc = match_isinlist(US"non-participant", &arg, 0, NULL,
2587 NULL, MCL_STRING, TRUE, NULL);
2589 case DK_EXIM_RESULT_GOOD:
2590 rc = match_isinlist(US"good", &arg, 0, NULL,
2591 NULL, MCL_STRING, TRUE, NULL);
2593 case DK_EXIM_RESULT_BAD:
2594 rc = match_isinlist(US"bad", &arg, 0, NULL,
2595 NULL, MCL_STRING, TRUE, NULL);
2603 rc = verify_check_dnsbl(&arg);
2607 rc = match_isinlist(addr->domain, &arg, 0, &domainlist_anchor,
2608 addr->domain_cache, MCL_DOMAIN, TRUE, &deliver_domain_data);
2611 /* The value in tls_cipher is the full cipher name, for example,
2612 TLSv1:DES-CBC3-SHA:168, whereas the values to test for are just the
2613 cipher names such as DES-CBC3-SHA. But program defensively. We don't know
2614 what may in practice come out of the SSL library - which at the time of
2615 writing is poorly documented. */
2617 case ACLC_ENCRYPTED:
2618 if (tls_cipher == NULL) rc = FAIL; else
2620 uschar *endcipher = NULL;
2621 uschar *cipher = Ustrchr(tls_cipher, ':');
2622 if (cipher == NULL) cipher = tls_cipher; else
2624 endcipher = Ustrchr(++cipher, ':');
2625 if (endcipher != NULL) *endcipher = 0;
2627 rc = match_isinlist(cipher, &arg, 0, NULL, NULL, MCL_STRING, TRUE, NULL);
2628 if (endcipher != NULL) *endcipher = ':';
2632 /* Use verify_check_this_host() instead of verify_check_host() so that
2633 we can pass over &host_data to catch any looked up data. Once it has been
2634 set, it retains its value so that it's still there if another ACL verb
2635 comes through here and uses the cache. However, we must put it into
2636 permanent store in case it is also expected to be used in a subsequent
2637 message in the same SMTP connection. */
2640 rc = verify_check_this_host(&arg, sender_host_cache, NULL,
2641 (sender_host_address == NULL)? US"" : sender_host_address, &host_data);
2642 if (host_data != NULL) host_data = string_copy_malloc(host_data);
2645 case ACLC_LOCAL_PARTS:
2646 rc = match_isinlist(addr->cc_local_part, &arg, 0,
2647 &localpartlist_anchor, addr->localpart_cache, MCL_LOCALPART, TRUE,
2648 &deliver_localpart_data);
2660 if (Ustrncmp(s, "main", 4) == 0)
2661 { logbits |= LOG_MAIN; s += 4; }
2662 else if (Ustrncmp(s, "panic", 5) == 0)
2663 { logbits |= LOG_PANIC; s += 5; }
2664 else if (Ustrncmp(s, "reject", 6) == 0)
2665 { logbits |= LOG_REJECT; s += 6; }
2668 logbits = LOG_MAIN|LOG_PANIC;
2669 s = string_sprintf(":unknown log name in \"%s\" in "
2670 "\"logwrite\" in %s ACL", arg, acl_wherenames[where]);
2676 while (isspace(*s)) s++;
2677 if (logbits == 0) logbits = LOG_MAIN;
2678 log_write(0, logbits, "%s", string_printing(s));
2682 #ifdef WITH_CONTENT_SCAN
2685 /* Seperate the regular expression and any optional parameters. */
2686 uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size);
2687 /* Run the malware backend. */
2689 /* Modify return code based upon the existance of options. */
2690 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2692 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
2694 /* FAIL so that the message is passed to the next ACL */
2701 case ACLC_MIME_REGEX:
2702 rc = mime_regex(&arg);
2706 case ACLC_RATELIMIT:
2707 rc = acl_ratelimit(arg, log_msgptr);
2710 case ACLC_RECIPIENTS:
2711 rc = match_address_list(addr->address, TRUE, TRUE, &arg, NULL, -1, 0,
2715 #ifdef WITH_CONTENT_SCAN
2721 case ACLC_SENDER_DOMAINS:
2724 sdomain = Ustrrchr(sender_address, '@');
2725 sdomain = (sdomain == NULL)? US"" : sdomain + 1;
2726 rc = match_isinlist(sdomain, &arg, 0, &domainlist_anchor,
2727 sender_domain_cache, MCL_DOMAIN, TRUE, NULL);
2732 rc = match_address_list(sender_address, TRUE, TRUE, &arg,
2733 sender_address_cache, -1, 0, &sender_data);
2736 /* Connection variables must persist forever */
2740 int old_pool = store_pool;
2741 if (cb->u.varnumber < ACL_C_MAX) store_pool = POOL_PERM;
2742 acl_var[cb->u.varnumber] = string_copy(arg);
2743 store_pool = old_pool;
2747 #ifdef WITH_CONTENT_SCAN
2750 /* Seperate the regular expression and any optional parameters. */
2751 uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size);
2752 /* Run the spam backend. */
2754 /* Modify return code based upon the existance of options. */
2755 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2757 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
2759 /* FAIL so that the message is passed to the next ACL */
2767 #ifdef EXPERIMENTAL_SPF
2769 rc = spf_process(&arg, sender_address);
2773 /* If the verb is WARN, discard any user message from verification, because
2774 such messages are SMTP responses, not header additions. The latter come
2775 only from explicit "message" modifiers. However, put the user message into
2776 $acl_verify_message so it can be used in subsequent conditions or modifiers
2777 (until something changes it). */
2780 rc = acl_verify(where, addr, arg, user_msgptr, log_msgptr, basic_errno);
2781 acl_verify_message = *user_msgptr;
2782 if (verb == ACL_WARN) *user_msgptr = NULL;
2786 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown "
2787 "condition %d", cb->type);
2791 /* If a condition was negated, invert OK/FAIL. */
2793 if (!cond_modifiers[cb->type] && cb->u.negated)
2795 if (rc == OK) rc = FAIL;
2796 else if (rc == FAIL || rc == FAIL_DROP) rc = OK;
2799 if (rc != OK) break; /* Conditions loop */
2803 /* If the result is the one for which "message" and/or "log_message" are used,
2804 handle the values of these options. Most verbs have but a single return for
2805 which the messages are relevant, but for "discard", it's useful to have the log
2806 message both when it succeeds and when it fails. Also, for an "accept" that
2807 appears in a QUIT ACL, we want to handle the user message. Since only "accept"
2808 and "warn" are permitted in that ACL, we don't need to test the verb.
2810 These modifiers act in different ways:
2812 "message" is a user message that will be included in an SMTP response. Unless
2813 it is empty, it overrides any previously set user message.
2815 "log_message" is a non-user message, and it adds to any existing non-user
2816 message that is already set.
2818 If there isn't a log message set, we make it the same as the user message. */
2820 if (((rc == FAIL_DROP)? FAIL : rc) == msgcond[verb] ||
2821 (verb == ACL_DISCARD && rc == OK) ||
2822 (where == ACL_WHERE_QUIT))
2826 /* If the verb is "warn", messages generated by conditions (verification or
2827 nested ACLs) are discarded. Only messages specified at this level are used.
2828 However, the value of an existing message is available in $acl_verify_message
2829 during expansions. */
2831 uschar *old_user_msgptr = *user_msgptr;
2832 uschar *old_log_msgptr = (*log_msgptr != NULL)? *log_msgptr : old_user_msgptr;
2834 if (verb == ACL_WARN) *log_msgptr = *user_msgptr = NULL;
2836 if (user_message != NULL)
2838 acl_verify_message = old_user_msgptr;
2839 expmessage = expand_string(user_message);
2840 if (expmessage == NULL)
2842 if (!expand_string_forcedfail)
2843 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
2844 user_message, expand_string_message);
2846 else if (expmessage[0] != 0) *user_msgptr = expmessage;
2849 if (log_message != NULL)
2851 acl_verify_message = old_log_msgptr;
2852 expmessage = expand_string(log_message);
2853 if (expmessage == NULL)
2855 if (!expand_string_forcedfail)
2856 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
2857 log_message, expand_string_message);
2859 else if (expmessage[0] != 0)
2861 *log_msgptr = (*log_msgptr == NULL)? expmessage :
2862 string_sprintf("%s: %s", expmessage, *log_msgptr);
2866 /* If no log message, default it to the user message */
2868 if (*log_msgptr == NULL) *log_msgptr = *user_msgptr;
2871 acl_verify_message = NULL;
2879 /*************************************************
2880 * Get line from a literal ACL *
2881 *************************************************/
2883 /* This function is passed to acl_read() in order to extract individual lines
2884 of a literal ACL, which we access via static pointers. We can destroy the
2885 contents because this is called only once (the compiled ACL is remembered).
2887 This code is intended to treat the data in the same way as lines in the main
2888 Exim configuration file. That is:
2890 . Leading spaces are ignored.
2892 . A \ at the end of a line is a continuation - trailing spaces after the \
2893 are permitted (this is because I don't believe in making invisible things
2894 significant). Leading spaces on the continued part of a line are ignored.
2896 . Physical lines starting (significantly) with # are totally ignored, and
2897 may appear within a sequence of backslash-continued lines.
2899 . Blank lines are ignored, but will end a sequence of continuations.
2902 Returns: a pointer to the next line
2906 static uschar *acl_text; /* Current pointer in the text */
2907 static uschar *acl_text_end; /* Points one past the terminating '0' */
2915 /* This loop handles leading blank lines and comments. */
2919 while (isspace(*acl_text)) acl_text++; /* Leading spaces/empty lines */
2920 if (*acl_text == 0) return NULL; /* No more data */
2921 yield = acl_text; /* Potential data line */
2923 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
2925 /* If we hit the end before a newline, we have the whole logical line. If
2926 it's a comment, there's no more data to be given. Otherwise, yield it. */
2928 if (*acl_text == 0) return (*yield == '#')? NULL : yield;
2930 /* After reaching a newline, end this loop if the physical line does not
2931 start with '#'. If it does, it's a comment, and the loop continues. */
2933 if (*yield != '#') break;
2936 /* This loop handles continuations. We know we have some real data, ending in
2937 newline. See if there is a continuation marker at the end (ignoring trailing
2938 white space). We know that *yield is not white space, so no need to test for
2939 cont > yield in the backwards scanning loop. */
2944 for (cont = acl_text - 1; isspace(*cont); cont--);
2946 /* If no continuation follows, we are done. Mark the end of the line and
2955 /* We have encountered a continuation. Skip over whitespace at the start of
2956 the next line, and indeed the whole of the next line or lines if they are
2961 while (*(++acl_text) == ' ' || *acl_text == '\t');
2962 if (*acl_text != '#') break;
2963 while (*(++acl_text) != 0 && *acl_text != '\n');
2966 /* We have the start of a continuation line. Move all the rest of the data
2967 to join onto the previous line, and then find its end. If the end is not a
2968 newline, we are done. Otherwise loop to look for another continuation. */
2970 memmove(cont, acl_text, acl_text_end - acl_text);
2971 acl_text_end -= acl_text - cont;
2973 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
2974 if (*acl_text == 0) return yield;
2977 /* Control does not reach here */
2984 /*************************************************
2985 * Check access using an ACL *
2986 *************************************************/
2988 /* This function is called from address_check. It may recurse via
2989 acl_check_condition() - hence the use of a level to stop looping. The ACL is
2990 passed as a string which is expanded. A forced failure implies no access check
2991 is required. If the result is a single word, it is taken as the name of an ACL
2992 which is sought in the global ACL tree. Otherwise, it is taken as literal ACL
2993 text, complete with newlines, and parsed as such. In both cases, the ACL check
2994 is then run. This function uses an auxiliary function for acl_read() to call
2995 for reading individual lines of a literal ACL. This is acl_getline(), which
2996 appears immediately above.
2999 where where called from
3000 addr address item when called from RCPT; otherwise NULL
3001 s the input string; NULL is the same as an empty ACL => DENY
3002 level the nesting level
3003 user_msgptr where to put a user error (for SMTP response)
3004 log_msgptr where to put a logging message (not for SMTP response)
3006 Returns: OK access is granted
3007 DISCARD access is apparently granted...
3008 FAIL access is denied
3009 FAIL_DROP access is denied; drop the connection
3010 DEFER can't tell at the moment
3015 acl_check_internal(int where, address_item *addr, uschar *s, int level,
3016 uschar **user_msgptr, uschar **log_msgptr)
3019 acl_block *acl = NULL;
3020 uschar *acl_name = US"inline ACL";
3023 /* Catch configuration loops */
3027 *log_msgptr = US"ACL nested too deep: possible loop";
3033 HDEBUG(D_acl) debug_printf("ACL is NULL: implicit DENY\n");
3037 /* At top level, we expand the incoming string. At lower levels, it has already
3038 been expanded as part of condition processing. */
3042 ss = expand_string(s);
3045 if (expand_string_forcedfail) return OK;
3046 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s", s,
3047 expand_string_message);
3053 while (isspace(*ss))ss++;
3055 /* If we can't find a named ACL, the default is to parse it as an inline one.
3056 (Unless it begins with a slash; non-existent files give rise to an error.) */
3060 /* Handle the case of a string that does not contain any spaces. Look for a
3061 named ACL among those read from the configuration, or a previously read file.
3062 It is possible that the pointer to the ACL is NULL if the configuration
3063 contains a name with no data. If not found, and the text begins with '/',
3064 read an ACL from a file, and save it so it can be re-used. */
3066 if (Ustrchr(ss, ' ') == NULL)
3068 tree_node *t = tree_search(acl_anchor, ss);
3071 acl = (acl_block *)(t->data.ptr);
3074 HDEBUG(D_acl) debug_printf("ACL \"%s\" is empty: implicit DENY\n", ss);
3077 acl_name = string_sprintf("ACL \"%s\"", ss);
3078 HDEBUG(D_acl) debug_printf("using ACL \"%s\"\n", ss);
3081 else if (*ss == '/')
3083 struct stat statbuf;
3084 fd = Uopen(ss, O_RDONLY, 0);
3087 *log_msgptr = string_sprintf("failed to open ACL file \"%s\": %s", ss,
3092 if (fstat(fd, &statbuf) != 0)
3094 *log_msgptr = string_sprintf("failed to fstat ACL file \"%s\": %s", ss,
3099 acl_text = store_get(statbuf.st_size + 1);
3100 acl_text_end = acl_text + statbuf.st_size + 1;
3102 if (read(fd, acl_text, statbuf.st_size) != statbuf.st_size)
3104 *log_msgptr = string_sprintf("failed to read ACL file \"%s\": %s",
3105 ss, strerror(errno));
3108 acl_text[statbuf.st_size] = 0;
3111 acl_name = string_sprintf("ACL \"%s\"", ss);
3112 HDEBUG(D_acl) debug_printf("read ACL from file %s\n", ss);
3116 /* Parse an ACL that is still in text form. If it came from a file, remember it
3117 in the ACL tree, having read it into the POOL_PERM store pool so that it
3118 persists between multiple messages. */
3122 int old_pool = store_pool;
3123 if (fd >= 0) store_pool = POOL_PERM;
3124 acl = acl_read(acl_getline, log_msgptr);
3125 store_pool = old_pool;
3126 if (acl == NULL && *log_msgptr != NULL) return ERROR;
3129 tree_node *t = store_get_perm(sizeof(tree_node) + Ustrlen(ss));
3130 Ustrcpy(t->name, ss);
3132 (void)tree_insertnode(&acl_anchor, t);
3136 /* Now we have an ACL to use. It's possible it may be NULL. */
3141 int basic_errno = 0;
3142 BOOL endpass_seen = FALSE;
3144 *log_msgptr = *user_msgptr = NULL;
3145 acl_temp_details = FALSE;
3147 if (where == ACL_WHERE_QUIT &&
3148 acl->verb != ACL_ACCEPT &&
3149 acl->verb != ACL_WARN)
3151 *log_msgptr = string_sprintf("\"%s\" is not allowed in a QUIT ACL",
3156 HDEBUG(D_acl) debug_printf("processing \"%s\"\n", verbs[acl->verb]);
3158 /* Clear out any search error message from a previous check before testing
3161 search_error_message = NULL;
3162 cond = acl_check_condition(acl->verb, acl->condition, where, addr, level,
3163 &endpass_seen, user_msgptr, log_msgptr, &basic_errno);
3165 /* Handle special returns: DEFER causes a return except on a WARN verb;
3166 ERROR always causes a return. */
3171 HDEBUG(D_acl) debug_printf("%s: condition test deferred\n", verbs[acl->verb]);
3172 if (basic_errno != ERRNO_CALLOUTDEFER)
3174 if (search_error_message != NULL && *search_error_message != 0)
3175 *log_msgptr = search_error_message;
3176 if (smtp_return_error_details) acl_temp_details = TRUE;
3180 acl_temp_details = TRUE;
3182 if (acl->verb != ACL_WARN) return DEFER;
3185 default: /* Paranoia */
3187 HDEBUG(D_acl) debug_printf("%s: condition test error\n", verbs[acl->verb]);
3191 HDEBUG(D_acl) debug_printf("%s: condition test succeeded\n",
3196 HDEBUG(D_acl) debug_printf("%s: condition test failed\n", verbs[acl->verb]);
3199 /* DISCARD and DROP can happen only from a nested ACL condition, and
3200 DISCARD can happen only for an "accept" or "discard" verb. */
3203 HDEBUG(D_acl) debug_printf("%s: condition test yielded \"discard\"\n",
3208 HDEBUG(D_acl) debug_printf("%s: condition test yielded \"drop\"\n",
3213 /* At this point, cond for most verbs is either OK or FAIL or (as a result of
3214 a nested ACL condition) FAIL_DROP. However, for WARN, cond may be DEFER, and
3215 for ACCEPT and DISCARD, it may be DISCARD after a nested ACL call. */
3220 if (cond == OK || cond == DISCARD) return cond;
3223 HDEBUG(D_acl) debug_printf("accept: endpass encountered - denying access\n");
3231 acl_temp_details = TRUE;
3237 if (cond == OK) return FAIL;
3241 if (cond == OK || cond == DISCARD) return DISCARD;
3244 HDEBUG(D_acl) debug_printf("discard: endpass encountered - denying access\n");
3250 if (cond == OK) return FAIL_DROP;
3254 if (cond != OK) return cond;
3259 acl_warn(where, *user_msgptr, *log_msgptr);
3260 else if (cond == DEFER)
3261 log_write(0, LOG_MAIN, "%s Warning: ACL \"warn\" statement skipped: "
3262 "condition test deferred%s%s", host_and_ident(TRUE),
3263 (*log_msgptr == NULL)? US"" : US": ",
3264 (*log_msgptr == NULL)? US"" : *log_msgptr);
3265 *log_msgptr = *user_msgptr = NULL; /* In case implicit DENY follows */
3269 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown verb %d",
3274 /* Pass to the next ACL item */
3279 /* We have reached the end of the ACL. This is an implicit DENY. */
3281 HDEBUG(D_acl) debug_printf("end of %s: implicit DENY\n", acl_name);
3286 /*************************************************
3287 * Check access using an ACL *
3288 *************************************************/
3290 /* This is the external interface for ACL checks. It sets up an address and the
3291 expansions for $domain and $local_part when called after RCPT, then calls
3292 acl_check_internal() to do the actual work.
3295 where ACL_WHERE_xxxx indicating where called from
3296 data_string RCPT address, or SMTP command argument, or NULL
3297 s the input string; NULL is the same as an empty ACL => DENY
3298 user_msgptr where to put a user error (for SMTP response)
3299 log_msgptr where to put a logging message (not for SMTP response)
3301 Returns: OK access is granted by an ACCEPT verb
3302 DISCARD access is granted by a DISCARD verb
3303 FAIL access is denied
3304 FAIL_DROP access is denied; drop the connection
3305 DEFER can't tell at the moment
3310 acl_check(int where, uschar *data_string, uschar *s, uschar **user_msgptr,
3311 uschar **log_msgptr)
3317 *user_msgptr = *log_msgptr = NULL;
3318 sender_verified_failed = NULL;
3320 if (where == ACL_WHERE_RCPT)
3322 adb = address_defaults;
3324 addr->address = data_string;
3325 if (deliver_split_address(addr) == DEFER)
3327 *log_msgptr = US"defer in percent_hack_domains check";
3330 deliver_domain = addr->domain;
3331 deliver_localpart = addr->local_part;
3336 smtp_command_argument = data_string;
3339 rc = acl_check_internal(where, addr, s, 0, user_msgptr, log_msgptr);
3341 smtp_command_argument = deliver_domain =
3342 deliver_localpart = deliver_address_data = sender_address_data = NULL;
3344 /* A DISCARD response is permitted only for message ACLs, excluding the PREDATA
3345 ACL, which is really in the middle of an SMTP command. */
3349 if (where > ACL_WHERE_NOTSMTP || where == ACL_WHERE_PREDATA)
3351 log_write(0, LOG_MAIN|LOG_PANIC, "\"discard\" verb not allowed in %s "
3352 "ACL", acl_wherenames[where]);
3358 /* A DROP response is not permitted from MAILAUTH */
3360 if (rc == FAIL_DROP && where == ACL_WHERE_MAILAUTH)
3362 log_write(0, LOG_MAIN|LOG_PANIC, "\"drop\" verb not allowed in %s "
3363 "ACL", acl_wherenames[where]);
3367 /* Before giving an error response, take a look at the length of any user
3368 message, and split it up into multiple lines if possible. */
3370 if (rc != OK && *user_msgptr != NULL && Ustrlen(*user_msgptr) > 75)
3372 uschar *s = *user_msgptr = string_copy(*user_msgptr);
3378 while (i < 75 && *ss != 0 && *ss != '\n') ss++, i++;
3379 if (*ss == 0) break;
3386 while (--t > s + 35)
3390 if (t[-1] == ':') { tt = t; break; }
3391 if (tt == NULL) tt = t;
3395 if (tt == NULL) /* Can't split behind - try ahead */
3400 if (*t == ' ' || *t == '\n')
3406 if (tt == NULL) break; /* Can't find anywhere to split */