1 /* $Cambridge: exim/src/src/acl.c,v 1.45 2005/09/06 13:17:36 ph10 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[] = {
87 #ifdef EXPERIMENTAL_BRIGHTMAIL
92 #ifdef WITH_CONTENT_SCAN
96 #ifdef WITH_OLD_DEMIME
99 #ifdef EXPERIMENTAL_DOMAINKEYS
100 US"dk_domain_source",
102 US"dk_sender_domains",
103 US"dk_sender_local_parts",
107 US"dnslists", US"domains", US"encrypted",
108 US"endpass", US"hosts", US"local_parts", US"log_message", US"logwrite",
109 #ifdef WITH_CONTENT_SCAN
113 #ifdef WITH_CONTENT_SCAN
118 #ifdef WITH_CONTENT_SCAN
121 US"sender_domains", US"senders", US"set",
122 #ifdef WITH_CONTENT_SCAN
125 #ifdef EXPERIMENTAL_SPF
131 /* Return values from decode_control(); keep in step with the table of names
135 #ifdef EXPERIMENTAL_BRIGHTMAIL
138 #ifdef EXPERIMENTAL_DOMAINKEYS
141 CONTROL_ERROR, CONTROL_CASEFUL_LOCAL_PART, CONTROL_CASELOWER_LOCAL_PART,
142 CONTROL_ENFORCE_SYNC, CONTROL_NO_ENFORCE_SYNC, CONTROL_FREEZE,
143 CONTROL_QUEUE_ONLY, CONTROL_SUBMISSION,
144 #ifdef WITH_CONTENT_SCAN
145 CONTROL_NO_MBOX_UNSPOOL,
147 CONTROL_FAKEDEFER, CONTROL_FAKEREJECT, CONTROL_NO_MULTILINE };
149 /* ACL control names; keep in step with the table above! */
151 static uschar *controls[] = {
152 #ifdef EXPERIMENTAL_BRIGHTMAIL
155 #ifdef EXPERIMENTAL_DOMAINKEYS
158 US"error", US"caseful_local_part",
159 US"caselower_local_part", US"enforce_sync", US"no_enforce_sync", US"freeze",
160 US"queue_only", US"submission",
161 #ifdef WITH_CONTENT_SCAN
166 /* Flags to indicate for which conditions /modifiers a string expansion is done
167 at the outer level. In the other cases, expansion already occurs in the
168 checking functions. */
170 static uschar cond_expand_at_top[] = {
172 FALSE, /* authenticated */
173 #ifdef EXPERIMENTAL_BRIGHTMAIL
174 TRUE, /* bmi_optin */
176 TRUE, /* condition */
178 #ifdef WITH_CONTENT_SCAN
182 #ifdef WITH_OLD_DEMIME
185 #ifdef EXPERIMENTAL_DOMAINKEYS
186 TRUE, /* dk_domain_source */
187 TRUE, /* dk_policy */
188 TRUE, /* dk_sender_domains */
189 TRUE, /* dk_sender_local_parts */
190 TRUE, /* dk_senders */
191 TRUE, /* dk_status */
195 FALSE, /* encrypted */
198 FALSE, /* local_parts */
199 TRUE, /* log_message */
201 #ifdef WITH_CONTENT_SCAN
205 #ifdef WITH_CONTENT_SCAN
206 TRUE, /* mime_regex */
208 TRUE, /* ratelimit */
209 FALSE, /* recipients */
210 #ifdef WITH_CONTENT_SCAN
213 FALSE, /* sender_domains */
216 #ifdef WITH_CONTENT_SCAN
219 #ifdef EXPERIMENTAL_SPF
225 /* Flags to identify the modifiers */
227 static uschar cond_modifiers[] = {
229 FALSE, /* authenticated */
230 #ifdef EXPERIMENTAL_BRIGHTMAIL
231 TRUE, /* bmi_optin */
233 FALSE, /* condition */
235 #ifdef WITH_CONTENT_SCAN
239 #ifdef WITH_OLD_DEMIME
242 #ifdef EXPERIMENTAL_DOMAINKEYS
243 FALSE, /* dk_domain_source */
244 FALSE, /* dk_policy */
245 FALSE, /* dk_sender_domains */
246 FALSE, /* dk_sender_local_parts */
247 FALSE, /* dk_senders */
248 FALSE, /* dk_status */
250 FALSE, /* dnslists */
252 FALSE, /* encrypted */
255 FALSE, /* local_parts */
256 TRUE, /* log_message */
258 #ifdef WITH_CONTENT_SCAN
262 #ifdef WITH_CONTENT_SCAN
263 FALSE, /* mime_regex */
265 FALSE, /* ratelimit */
266 FALSE, /* recipients */
267 #ifdef WITH_CONTENT_SCAN
270 FALSE, /* sender_domains */
273 #ifdef WITH_CONTENT_SCAN
276 #ifdef EXPERIMENTAL_SPF
282 /* Bit map vector of which conditions are not allowed at certain times. For
283 each condition, there's a bitmap of dis-allowed times. For some, it is easier
284 to specify the negation of a small number of allowed times. */
286 static unsigned int cond_forbids[] = {
289 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_CONNECT)| /* authenticated */
292 #ifdef EXPERIMENTAL_BRIGHTMAIL
293 (1<<ACL_WHERE_AUTH)| /* bmi_optin */
294 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
295 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_MIME)|
296 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
297 (1<<ACL_WHERE_MAILAUTH)|
298 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
299 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_PREDATA),
304 /* Certain types of control are always allowed, so we let it through
305 always and check in the control processing itself. */
309 #ifdef WITH_CONTENT_SCAN
311 ~(1<<ACL_WHERE_MIME), /* decode */
316 #ifdef WITH_OLD_DEMIME
318 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)), /* demime */
321 #ifdef EXPERIMENTAL_DOMAINKEYS
322 (1<<ACL_WHERE_AUTH)| /* dk_domain_source */
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_policy */
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)|
338 (1<<ACL_WHERE_AUTH)| /* dk_sender_domains */
339 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
340 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
341 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
342 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
343 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
346 (1<<ACL_WHERE_AUTH)| /* dk_sender_local_parts */
347 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
348 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
349 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
350 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
351 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
354 (1<<ACL_WHERE_AUTH)| /* dk_senders */
355 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
356 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
357 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
358 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
359 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
362 (1<<ACL_WHERE_AUTH)| /* dk_status */
363 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
364 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
365 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
366 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
367 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
371 (1<<ACL_WHERE_NOTSMTP), /* dnslists */
374 ~(1<<ACL_WHERE_RCPT), /* domains */
376 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_CONNECT)| /* encrypted */
381 (1<<ACL_WHERE_NOTSMTP), /* hosts */
384 ~(1<<ACL_WHERE_RCPT), /* local_parts */
390 #ifdef WITH_CONTENT_SCAN
392 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)), /* malware */
397 #ifdef WITH_CONTENT_SCAN
399 ~(1<<ACL_WHERE_MIME), /* mime_regex */
405 ~(1<<ACL_WHERE_RCPT), /* recipients */
407 #ifdef WITH_CONTENT_SCAN
409 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* regex */
410 (1<<ACL_WHERE_MIME)),
413 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* sender_domains */
415 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
416 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
417 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
419 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* senders */
421 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
422 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
423 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
427 #ifdef WITH_CONTENT_SCAN
429 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)), /* spam */
432 #ifdef EXPERIMENTAL_SPF
433 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* spf */
435 (1<<ACL_WHERE_MAILAUTH)|
436 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
437 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
440 /* Certain types of verify are always allowed, so we let it through
441 always and check in the verify function itself */
447 /* Bit map vector of which controls are not allowed at certain times. For
448 each control, there's a bitmap of dis-allowed times. For some, it is easier to
449 specify the negation of a small number of allowed times. */
451 static unsigned int control_forbids[] = {
452 #ifdef EXPERIMENTAL_BRIGHTMAIL
455 #ifdef EXPERIMENTAL_DOMAINKEYS
456 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), /* dk_verify */
462 ~(1<<ACL_WHERE_RCPT), /* caseful_local_part */
465 ~(1<<ACL_WHERE_RCPT), /* caselower_local_part */
467 (1<<ACL_WHERE_NOTSMTP), /* enforce_sync */
469 (1<<ACL_WHERE_NOTSMTP), /* no_enforce_sync */
472 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* freeze */
473 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
474 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)),
477 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* queue_only */
478 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
479 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)),
482 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* submission */
483 (1<<ACL_WHERE_PREDATA)),
485 #ifdef WITH_CONTENT_SCAN
487 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* no_mbox_unspool */
488 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
489 (1<<ACL_WHERE_MIME)),
493 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakedefer */
494 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
495 (1<<ACL_WHERE_MIME)),
498 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakereject */
499 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
500 (1<<ACL_WHERE_MIME)),
502 (1<<ACL_WHERE_NOTSMTP) /* no_multiline */
505 /* Structure listing various control arguments, with their characteristics. */
507 typedef struct control_def {
509 int value; /* CONTROL_xxx value */
510 BOOL has_option; /* Has /option(s) following */
513 static control_def controls_list[] = {
514 #ifdef EXPERIMENTAL_BRIGHTMAIL
515 { US"bmi_run", CONTROL_BMI_RUN, FALSE},
517 #ifdef EXPERIMENTAL_DOMAINKEYS
518 { US"dk_verify", CONTROL_DK_VERIFY, FALSE},
520 { US"caseful_local_part", CONTROL_CASEFUL_LOCAL_PART, FALSE},
521 { US"caselower_local_part", CONTROL_CASELOWER_LOCAL_PART, FALSE},
522 { US"enforce_sync", CONTROL_ENFORCE_SYNC, FALSE},
523 { US"freeze", CONTROL_FREEZE, FALSE},
524 { US"no_enforce_sync", CONTROL_NO_ENFORCE_SYNC, FALSE},
525 { US"no_multiline_responses", CONTROL_NO_MULTILINE, FALSE},
526 { US"queue_only", CONTROL_QUEUE_ONLY, FALSE},
527 #ifdef WITH_CONTENT_SCAN
528 { US"no_mbox_unspool", CONTROL_NO_MBOX_UNSPOOL, FALSE},
530 { US"fakedefer", CONTROL_FAKEDEFER, TRUE},
531 { US"fakereject", CONTROL_FAKEREJECT, TRUE},
532 { US"submission", CONTROL_SUBMISSION, TRUE}
535 /* Support data structures for Client SMTP Authorization. acl_verify_csa()
536 caches its result in a tree to avoid repeated DNS queries. The result is an
537 integer code which is used as an index into the following tables of
538 explanatory strings and verification return codes. */
540 static tree_node *csa_cache = NULL;
542 enum { CSA_UNKNOWN, CSA_OK, CSA_DEFER_SRV, CSA_DEFER_ADDR,
543 CSA_FAIL_EXPLICIT, CSA_FAIL_DOMAIN, CSA_FAIL_NOADDR, CSA_FAIL_MISMATCH };
545 /* The acl_verify_csa() return code is translated into an acl_verify() return
546 code using the following table. It is OK unless the client is definitely not
547 authorized. This is because CSA is supposed to be optional for sending sites,
548 so recipients should not be too strict about checking it - especially because
549 DNS problems are quite likely to occur. It's possible to use $csa_status in
550 further ACL conditions to distinguish ok, unknown, and defer if required, but
551 the aim is to make the usual configuration simple. */
553 static int csa_return_code[] = {
555 FAIL, FAIL, FAIL, FAIL
558 static uschar *csa_status_string[] = {
559 US"unknown", US"ok", US"defer", US"defer",
560 US"fail", US"fail", US"fail", US"fail"
563 static uschar *csa_reason_string[] = {
566 US"deferred (SRV lookup failed)",
567 US"deferred (target address lookup failed)",
568 US"failed (explicit authorization required)",
569 US"failed (host name not authorized)",
570 US"failed (no authorized addresses)",
571 US"failed (client address mismatch)"
574 /* Enable recursion between acl_check_internal() and acl_check_condition() */
576 static int acl_check_internal(int, address_item *, uschar *, int, uschar **,
580 /*************************************************
581 * Pick out name from list *
582 *************************************************/
584 /* Use a binary chop method
591 Returns: offset in list, or -1 if not found
595 acl_checkname(uschar *name, uschar **list, int end)
601 int mid = (start + end)/2;
602 int c = Ustrcmp(name, list[mid]);
603 if (c == 0) return mid;
604 if (c < 0) end = mid; else start = mid + 1;
611 /*************************************************
612 * Read and parse one ACL *
613 *************************************************/
615 /* This function is called both from readconf in order to parse the ACLs in the
616 configuration file, and also when an ACL is encountered dynamically (e.g. as
617 the result of an expansion). It is given a function to call in order to
618 retrieve the lines of the ACL. This function handles skipping comments and
619 blank lines (where relevant).
622 func function to get next line of ACL
623 error where to put an error message
625 Returns: pointer to ACL, or NULL
626 NULL can be legal (empty ACL); in this case error will be NULL
630 acl_read(uschar *(*func)(void), uschar **error)
632 acl_block *yield = NULL;
633 acl_block **lastp = &yield;
634 acl_block *this = NULL;
635 acl_condition_block *cond;
636 acl_condition_block **condp = NULL;
641 while ((s = (*func)()) != NULL)
644 BOOL negated = FALSE;
645 uschar *saveline = s;
648 /* Conditions (but not verbs) are allowed to be negated by an initial
651 while (isspace(*s)) s++;
658 /* Read the name of a verb or a condition, or the start of a new ACL, which
659 can be started by a name, or by a macro definition. */
661 s = readconf_readname(name, sizeof(name), s);
662 if (*s == ':' || isupper(name[0] && *s == '=')) return yield;
664 /* If a verb is unrecognized, it may be another condition or modifier that
665 continues the previous verb. */
667 v = acl_checkname(name, verbs, sizeof(verbs)/sizeof(char *));
672 *error = string_sprintf("unknown ACL verb in \"%s\"", saveline);
683 *error = string_sprintf("malformed ACL line \"%s\"", saveline);
686 this = store_get(sizeof(acl_block));
688 lastp = &(this->next);
691 this->condition = NULL;
692 condp = &(this->condition);
693 if (*s == 0) continue; /* No condition on this line */
699 s = readconf_readname(name, sizeof(name), s); /* Condition name */
702 /* Handle a condition or modifier. */
704 c = acl_checkname(name, conditions, sizeof(conditions)/sizeof(char *));
707 *error = string_sprintf("unknown ACL condition/modifier in \"%s\"",
712 /* The modifiers may not be negated */
714 if (negated && cond_modifiers[c])
716 *error = string_sprintf("ACL error: negation is not allowed with "
717 "\"%s\"", conditions[c]);
721 /* ENDPASS may occur only with ACCEPT or DISCARD. */
723 if (c == ACLC_ENDPASS &&
724 this->verb != ACL_ACCEPT &&
725 this->verb != ACL_DISCARD)
727 *error = string_sprintf("ACL error: \"%s\" is not allowed with \"%s\"",
728 conditions[c], verbs[this->verb]);
732 cond = store_get(sizeof(acl_condition_block));
735 cond->u.negated = negated;
738 condp = &(cond->next);
740 /* The "set" modifier is different in that its argument is "name=value"
741 rather than just a value, and we can check the validity of the name, which
742 gives us a variable number to insert into the data block. */
746 if (Ustrncmp(s, "acl_", 4) != 0 || (s[4] != 'c' && s[4] != 'm') ||
747 !isdigit(s[5]) || (!isspace(s[6]) && s[6] != '='))
749 *error = string_sprintf("unrecognized name after \"set\" in ACL "
750 "modifier \"set %s\"", s);
754 cond->u.varnumber = s[5] - '0';
755 if (s[4] == 'm') cond->u.varnumber += ACL_C_MAX;
757 while (isspace(*s)) s++;
760 /* For "set", we are now positioned for the data. For the others, only
761 "endpass" has no data */
763 if (c != ACLC_ENDPASS)
767 *error = string_sprintf("\"=\" missing after ACL \"%s\" %s", name,
768 cond_modifiers[c]? US"modifier" : US"condition");
771 while (isspace(*s)) s++;
772 cond->arg = string_copy(s);
781 /*************************************************
783 *************************************************/
785 /* This function is called when a WARN verb's conditions are true. It adds to
786 the message's headers, and/or writes information to the log. In each case, this
787 only happens once (per message for headers, per connection for log).
790 where ACL_WHERE_xxxx indicating which ACL this is
791 user_message message for adding to headers
792 log_message message for logging, if different
798 acl_warn(int where, uschar *user_message, uschar *log_message)
802 if (log_message != NULL && log_message != user_message)
807 text = string_sprintf("%s Warning: %s", host_and_ident(TRUE),
808 string_printing(log_message));
810 /* If a sender verification has failed, and the log message is "sender verify
811 failed", add the failure message. */
813 if (sender_verified_failed != NULL &&
814 sender_verified_failed->message != NULL &&
815 strcmpic(log_message, US"sender verify failed") == 0)
816 text = string_sprintf("%s: %s", text, sender_verified_failed->message);
818 /* Search previously logged warnings. They are kept in malloc
819 store so they can be freed at the start of a new message. */
821 for (logged = acl_warn_logged; logged != NULL; logged = logged->next)
822 if (Ustrcmp(logged->text, text) == 0) break;
826 int length = Ustrlen(text) + 1;
827 log_write(0, LOG_MAIN, "%s", text);
828 logged = store_malloc(sizeof(string_item) + length);
829 logged->text = (uschar *)logged + sizeof(string_item);
830 memcpy(logged->text, text, length);
831 logged->next = acl_warn_logged;
832 acl_warn_logged = logged;
836 /* If there's no user message, we are done. */
838 if (user_message == NULL) return;
840 /* If this isn't a message ACL, we can't do anything with a user message.
843 if (where > ACL_WHERE_NOTSMTP)
845 log_write(0, LOG_MAIN|LOG_PANIC, "ACL \"warn\" with \"message\" setting "
846 "found in a non-message (%s) ACL: cannot specify header lines here: "
847 "message ignored", acl_wherenames[where]);
851 /* Treat the user message as a sequence of one or more header lines. */
853 hlen = Ustrlen(user_message);
856 uschar *text, *p, *q;
858 /* Add a final newline if not present */
860 text = ((user_message)[hlen-1] == '\n')? user_message :
861 string_sprintf("%s\n", user_message);
863 /* Loop for multiple header lines, taking care about continuations */
865 for (p = q = text; *p != 0; )
868 int newtype = htype_add_bot;
869 header_line **hptr = &acl_warn_headers;
871 /* Find next header line within the string */
875 q = Ustrchr(q, '\n');
876 if (*(++q) != ' ' && *q != '\t') break;
879 /* If the line starts with a colon, interpret the instruction for where to
880 add it. This temporarily sets up a new type. */
884 if (strncmpic(p, US":after_received:", 16) == 0)
886 newtype = htype_add_rec;
889 else if (strncmpic(p, US":at_start_rfc:", 14) == 0)
891 newtype = htype_add_rfc;
894 else if (strncmpic(p, US":at_start:", 10) == 0)
896 newtype = htype_add_top;
899 else if (strncmpic(p, US":at_end:", 8) == 0)
901 newtype = htype_add_bot;
904 while (*p == ' ' || *p == '\t') p++;
907 /* See if this line starts with a header name, and if not, add X-ACL-Warn:
908 to the front of it. */
910 for (s = p; s < q - 1; s++)
912 if (*s == ':' || !isgraph(*s)) break;
915 s = string_sprintf("%s%.*s", (*s == ':')? "" : "X-ACL-Warn: ", q - p, p);
918 /* See if this line has already been added */
920 while (*hptr != NULL)
922 if (Ustrncmp((*hptr)->text, s, hlen) == 0) break;
923 hptr = &((*hptr)->next);
926 /* Add if not previously present */
930 header_line *h = store_get(sizeof(header_line));
939 /* Advance for next header line within the string */
948 /*************************************************
949 * Verify and check reverse DNS *
950 *************************************************/
952 /* Called from acl_verify() below. We look up the host name(s) of the client IP
953 address if this has not yet been done. The host_name_lookup() function checks
954 that one of these names resolves to an address list that contains the client IP
955 address, so we don't actually have to do the check here.
958 user_msgptr pointer for user message
959 log_msgptr pointer for log message
961 Returns: OK verification condition succeeded
962 FAIL verification failed
963 DEFER there was a problem verifying
967 acl_verify_reverse(uschar **user_msgptr, uschar **log_msgptr)
971 user_msgptr = user_msgptr; /* stop compiler warning */
973 /* Previous success */
975 if (sender_host_name != NULL) return OK;
977 /* Previous failure */
979 if (host_lookup_failed)
981 *log_msgptr = string_sprintf("host lookup failed%s", host_lookup_msg);
985 /* Need to do a lookup */
988 debug_printf("looking up host name to force name/address consistency check\n");
990 if ((rc = host_name_lookup()) != OK)
992 *log_msgptr = (rc == DEFER)?
993 US"host lookup deferred for reverse lookup check"
995 string_sprintf("host lookup failed for reverse lookup check%s",
997 return rc; /* DEFER or FAIL */
1000 host_build_sender_fullhost();
1006 /*************************************************
1007 * Check client IP address matches CSA target *
1008 *************************************************/
1010 /* Called from acl_verify_csa() below. This routine scans a section of a DNS
1011 response for address records belonging to the CSA target hostname. The section
1012 is specified by the reset argument, either RESET_ADDITIONAL or RESET_ANSWERS.
1013 If one of the addresses matches the client's IP address, then the client is
1014 authorized by CSA. If there are target IP addresses but none of them match
1015 then the client is using an unauthorized IP address. If there are no target IP
1016 addresses then the client cannot be using an authorized IP address. (This is
1017 an odd configuration - why didn't the SRV record have a weight of 1 instead?)
1020 dnsa the DNS answer block
1021 dnss a DNS scan block for us to use
1022 reset option specifing what portion to scan, as described above
1023 target the target hostname to use for matching RR names
1025 Returns: CSA_OK successfully authorized
1026 CSA_FAIL_MISMATCH addresses found but none matched
1027 CSA_FAIL_NOADDR no target addresses found
1031 acl_verify_csa_address(dns_answer *dnsa, dns_scan *dnss, int reset,
1037 BOOL target_found = FALSE;
1039 for (rr = dns_next_rr(dnsa, dnss, reset);
1041 rr = dns_next_rr(dnsa, dnss, RESET_NEXT))
1043 /* Check this is an address RR for the target hostname. */
1047 && rr->type != T_AAAA
1054 if (strcmpic(target, rr->name) != 0) continue;
1056 target_found = TRUE;
1058 /* Turn the target address RR into a list of textual IP addresses and scan
1059 the list. There may be more than one if it is an A6 RR. */
1061 for (da = dns_address_from_rr(dnsa, rr); da != NULL; da = da->next)
1063 /* If the client IP address matches the target IP address, it's good! */
1065 DEBUG(D_acl) debug_printf("CSA target address is %s\n", da->address);
1067 if (strcmpic(sender_host_address, da->address) == 0) return CSA_OK;
1071 /* If we found some target addresses but none of them matched, the client is
1072 using an unauthorized IP address, otherwise the target has no authorized IP
1075 if (target_found) return CSA_FAIL_MISMATCH;
1076 else return CSA_FAIL_NOADDR;
1081 /*************************************************
1082 * Verify Client SMTP Authorization *
1083 *************************************************/
1085 /* Called from acl_verify() below. This routine calls dns_lookup_special()
1086 to find the CSA SRV record corresponding to the domain argument, or
1087 $sender_helo_name if no argument is provided. It then checks that the
1088 client is authorized, and that its IP address corresponds to the SRV
1089 target's address by calling acl_verify_csa_address() above. The address
1090 should have been returned in the DNS response's ADDITIONAL section, but if
1091 not we perform another DNS lookup to get it.
1094 domain pointer to optional parameter following verify = csa
1096 Returns: CSA_UNKNOWN no valid CSA record found
1097 CSA_OK successfully authorized
1098 CSA_FAIL_* client is definitely not authorized
1099 CSA_DEFER_* there was a DNS problem
1103 acl_verify_csa(uschar *domain)
1107 int priority, weight, port;
1114 /* Work out the domain we are using for the CSA lookup. The default is the
1115 client's HELO domain. If the client has not said HELO, use its IP address
1116 instead. If it's a local client (exim -bs), CSA isn't applicable. */
1118 while (isspace(*domain) && *domain != '\0') ++domain;
1119 if (*domain == '\0') domain = sender_helo_name;
1120 if (domain == NULL) domain = sender_host_address;
1121 if (sender_host_address == NULL) return CSA_UNKNOWN;
1123 /* If we have an address literal, strip off the framing ready for turning it
1124 into a domain. The framing consists of matched square brackets possibly
1125 containing a keyword and a colon before the actual IP address. */
1127 if (domain[0] == '[')
1129 uschar *start = Ustrchr(domain, ':');
1130 if (start == NULL) start = domain;
1131 domain = string_copyn(start + 1, Ustrlen(start) - 2);
1134 /* Turn domains that look like bare IP addresses into domains in the reverse
1135 DNS. This code also deals with address literals and $sender_host_address. It's
1136 not quite kosher to treat bare domains such as EHLO 192.0.2.57 the same as
1137 address literals, but it's probably the most friendly thing to do. This is an
1138 extension to CSA, so we allow it to be turned off for proper conformance. */
1140 if (string_is_ip_address(domain, NULL))
1142 if (!dns_csa_use_reverse) return CSA_UNKNOWN;
1143 dns_build_reverse(domain, target);
1147 /* Find out if we've already done the CSA check for this domain. If we have,
1148 return the same result again. Otherwise build a new cached result structure
1149 for this domain. The name is filled in now, and the value is filled in when
1150 we return from this function. */
1152 t = tree_search(csa_cache, domain);
1153 if (t != NULL) return t->data.val;
1155 t = store_get_perm(sizeof(tree_node) + Ustrlen(domain));
1156 Ustrcpy(t->name, domain);
1157 (void)tree_insertnode(&csa_cache, t);
1159 /* Now we are ready to do the actual DNS lookup(s). */
1162 switch (dns_special_lookup(&dnsa, domain, T_CSA, &found))
1164 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1167 return t->data.val = CSA_DEFER_SRV;
1169 /* If we found nothing, the client's authorization is unknown. */
1173 return t->data.val = CSA_UNKNOWN;
1175 /* We got something! Go on to look at the reply in more detail. */
1181 /* Scan the reply for well-formed CSA SRV records. */
1183 for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS);
1185 rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT))
1187 if (rr->type != T_SRV) continue;
1189 /* Extract the numerical SRV fields (p is incremented) */
1192 GETSHORT(priority, p);
1193 GETSHORT(weight, p);
1197 debug_printf("CSA priority=%d weight=%d port=%d\n", priority, weight, port);
1199 /* Check the CSA version number */
1201 if (priority != 1) continue;
1203 /* If the domain does not have a CSA SRV record of its own (i.e. the domain
1204 found by dns_special_lookup() is a parent of the one we asked for), we check
1205 the subdomain assertions in the port field. At the moment there's only one
1206 assertion: legitimate SMTP clients are all explicitly authorized with CSA
1207 SRV records of their own. */
1209 if (found != domain)
1212 return t->data.val = CSA_FAIL_EXPLICIT;
1214 return t->data.val = CSA_UNKNOWN;
1217 /* This CSA SRV record refers directly to our domain, so we check the value
1218 in the weight field to work out the domain's authorization. 0 and 1 are
1219 unauthorized; 3 means the client is authorized but we can't check the IP
1220 address in order to authenticate it, so we treat it as unknown; values
1221 greater than 3 are undefined. */
1223 if (weight < 2) return t->data.val = CSA_FAIL_DOMAIN;
1225 if (weight > 2) continue;
1227 /* Weight == 2, which means the domain is authorized. We must check that the
1228 client's IP address is listed as one of the SRV target addresses. Save the
1229 target hostname then break to scan the additional data for its addresses. */
1231 (void)dn_expand(dnsa.answer, dnsa.answer + dnsa.answerlen, p,
1232 (DN_EXPAND_ARG4_TYPE)target, sizeof(target));
1234 DEBUG(D_acl) debug_printf("CSA target is %s\n", target);
1239 /* If we didn't break the loop then no appropriate records were found. */
1241 if (rr == NULL) return t->data.val = CSA_UNKNOWN;
1243 /* Do not check addresses if the target is ".", in accordance with RFC 2782.
1244 A target of "." indicates there are no valid addresses, so the client cannot
1245 be authorized. (This is an odd configuration because weight=2 target=. is
1246 equivalent to weight=1, but we check for it in order to keep load off the
1247 root name servers.) Note that dn_expand() turns "." into "". */
1249 if (Ustrcmp(target, "") == 0) return t->data.val = CSA_FAIL_NOADDR;
1251 /* Scan the additional section of the CSA SRV reply for addresses belonging
1252 to the target. If the name server didn't return any additional data (e.g.
1253 because it does not fully support SRV records), we need to do another lookup
1254 to obtain the target addresses; otherwise we have a definitive result. */
1256 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ADDITIONAL, target);
1257 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1259 /* The DNS lookup type corresponds to the IP version used by the client. */
1262 if (Ustrchr(sender_host_address, ':') != NULL)
1265 #endif /* HAVE_IPV6 */
1269 #if HAVE_IPV6 && defined(SUPPORT_A6)
1273 switch (dns_lookup(&dnsa, target, type, NULL))
1275 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1278 return t->data.val = CSA_DEFER_ADDR;
1280 /* If the query succeeded, scan the addresses and return the result. */
1283 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ANSWERS, target);
1284 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1285 /* else fall through */
1287 /* If the target has no IP addresses, the client cannot have an authorized
1288 IP address. However, if the target site uses A6 records (not AAAA records)
1289 we have to do yet another lookup in order to check them. */
1294 #if HAVE_IPV6 && defined(SUPPORT_A6)
1295 if (type == T_AAAA) { type = T_A6; goto DNS_LOOKUP_AGAIN; }
1298 return t->data.val = CSA_FAIL_NOADDR;
1304 /*************************************************
1305 * Handle verification (address & other) *
1306 *************************************************/
1308 /* This function implements the "verify" condition. It is called when
1309 encountered in any ACL, because some tests are almost always permitted. Some
1310 just don't make sense, and always fail (for example, an attempt to test a host
1311 lookup for a non-TCP/IP message). Others are restricted to certain ACLs.
1314 where where called from
1315 addr the recipient address that the ACL is handling, or NULL
1316 arg the argument of "verify"
1317 user_msgptr pointer for user message
1318 log_msgptr pointer for log message
1319 basic_errno where to put verify errno
1321 Returns: OK verification condition succeeded
1322 FAIL verification failed
1323 DEFER there was a problem verifying
1328 acl_verify(int where, address_item *addr, uschar *arg,
1329 uschar **user_msgptr, uschar **log_msgptr, int *basic_errno)
1333 int callout_overall = -1;
1334 int callout_connect = -1;
1335 int verify_options = 0;
1337 BOOL verify_header_sender = FALSE;
1338 BOOL defer_ok = FALSE;
1339 BOOL callout_defer_ok = FALSE;
1340 BOOL no_details = FALSE;
1341 BOOL success_on_redirect = FALSE;
1342 address_item *sender_vaddr = NULL;
1343 uschar *verify_sender_address = NULL;
1344 uschar *pm_mailfrom = NULL;
1345 uschar *se_mailfrom = NULL;
1347 /* Some of the verify items have slash-separated options; some do not. Diagnose
1348 an error if options are given for items that don't expect them. This code has
1349 now got very message. Refactoring to use a table would be a good idea one day.
1352 uschar *slash = Ustrchr(arg, '/');
1354 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
1356 if (ss == NULL) goto BAD_VERIFY;
1358 /* Handle name/address consistency verification in a separate function. */
1360 if (strcmpic(ss, US"reverse_host_lookup") == 0)
1362 if (slash != NULL) goto NO_OPTIONS;
1363 if (sender_host_address == NULL) return OK;
1364 return acl_verify_reverse(user_msgptr, log_msgptr);
1367 /* TLS certificate verification is done at STARTTLS time; here we just
1368 test whether it was successful or not. (This is for optional verification; for
1369 mandatory verification, the connection doesn't last this long.) */
1371 if (strcmpic(ss, US"certificate") == 0)
1373 if (slash != NULL) goto NO_OPTIONS;
1374 if (tls_certificate_verified) return OK;
1375 *user_msgptr = US"no verified certificate";
1379 /* We can test the result of optional HELO verification that might have
1380 occurred earlier. If not, we can attempt the verification now. */
1382 if (strcmpic(ss, US"helo") == 0)
1384 if (slash != NULL) goto NO_OPTIONS;
1385 if (helo_verified) return OK;
1386 if (helo_verify_failed) return FAIL;
1387 if (smtp_verify_helo()) return helo_verified? OK : FAIL;
1391 /* Do Client SMTP Authorization checks in a separate function, and turn the
1392 result code into user-friendly strings. */
1394 if (strcmpic(ss, US"csa") == 0)
1396 rc = acl_verify_csa(list);
1397 *log_msgptr = *user_msgptr = string_sprintf("client SMTP authorization %s",
1398 csa_reason_string[rc]);
1399 csa_status = csa_status_string[rc];
1400 DEBUG(D_acl) debug_printf("CSA result %s\n", csa_status);
1401 return csa_return_code[rc];
1404 /* Check that all relevant header lines have the correct syntax. If there is
1405 a syntax error, we return details of the error to the sender if configured to
1406 send out full details. (But a "message" setting on the ACL can override, as
1409 if (strcmpic(ss, US"header_syntax") == 0)
1411 if (slash != NULL) goto NO_OPTIONS;
1412 if (where != ACL_WHERE_DATA && where != ACL_WHERE_NOTSMTP) goto WRONG_ACL;
1413 rc = verify_check_headers(log_msgptr);
1414 if (rc != OK && smtp_return_error_details && *log_msgptr != NULL)
1415 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1419 /* Check that no recipient of this message is "blind", that is, every envelope
1420 recipient must be mentioned in either To: or Cc:. */
1422 if (strcmpic(ss, US"not_blind") == 0)
1424 if (slash != NULL) goto NO_OPTIONS;
1425 if (where != ACL_WHERE_DATA && where != ACL_WHERE_NOTSMTP) goto WRONG_ACL;
1426 rc = verify_check_notblind();
1429 *log_msgptr = string_sprintf("bcc recipient detected");
1430 if (smtp_return_error_details)
1431 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1436 /* The remaining verification tests check recipient and sender addresses,
1437 either from the envelope or from the header. There are a number of
1438 slash-separated options that are common to all of them. */
1441 /* Check that there is at least one verifiable sender address in the relevant
1442 header lines. This can be followed by callout and defer options, just like
1443 sender and recipient. */
1445 if (strcmpic(ss, US"header_sender") == 0)
1447 if (where != ACL_WHERE_DATA && where != ACL_WHERE_NOTSMTP) goto WRONG_ACL;
1448 verify_header_sender = TRUE;
1451 /* Otherwise, first item in verify argument must be "sender" or "recipient".
1452 In the case of a sender, this can optionally be followed by an address to use
1453 in place of the actual sender (rare special-case requirement). */
1455 else if (strncmpic(ss, US"sender", 6) == 0)
1458 if (where > ACL_WHERE_NOTSMTP)
1460 *log_msgptr = string_sprintf("cannot verify sender in ACL for %s "
1461 "(only possible for MAIL, RCPT, PREDATA, or DATA)",
1462 acl_wherenames[where]);
1466 verify_sender_address = sender_address;
1469 while (isspace(*s)) s++;
1470 if (*s++ != '=') goto BAD_VERIFY;
1471 while (isspace(*s)) s++;
1472 verify_sender_address = string_copy(s);
1477 if (strcmpic(ss, US"recipient") != 0) goto BAD_VERIFY;
1480 *log_msgptr = string_sprintf("cannot verify recipient in ACL for %s "
1481 "(only possible for RCPT)", acl_wherenames[where]);
1486 /* Remaining items are optional; they apply to sender and recipient
1487 verification, including "header sender" verification. */
1489 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size))
1492 if (strcmpic(ss, US"defer_ok") == 0) defer_ok = TRUE;
1493 else if (strcmpic(ss, US"no_details") == 0) no_details = TRUE;
1494 else if (strcmpic(ss, US"success_on_redirect") == 0) success_on_redirect = TRUE;
1496 /* These two old options are left for backwards compatibility */
1498 else if (strcmpic(ss, US"callout_defer_ok") == 0)
1500 callout_defer_ok = TRUE;
1501 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1504 else if (strcmpic(ss, US"check_postmaster") == 0)
1507 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1510 /* The callout option has a number of sub-options, comma separated */
1512 else if (strncmpic(ss, US"callout", 7) == 0)
1514 callout = CALLOUT_TIMEOUT_DEFAULT;
1518 while (isspace(*ss)) ss++;
1524 while (isspace(*ss)) ss++;
1526 /* This callout option handling code has become a mess as new options
1527 have been added in an ad hoc manner. It should be tidied up into some
1528 kind of table-driven thing. */
1530 while ((opt = string_nextinlist(&ss, &optsep, buffer, sizeof(buffer)))
1533 if (strcmpic(opt, US"defer_ok") == 0) callout_defer_ok = TRUE;
1534 else if (strcmpic(opt, US"no_cache") == 0)
1535 verify_options |= vopt_callout_no_cache;
1536 else if (strcmpic(opt, US"random") == 0)
1537 verify_options |= vopt_callout_random;
1538 else if (strcmpic(opt, US"use_sender") == 0)
1539 verify_options |= vopt_callout_recipsender;
1540 else if (strcmpic(opt, US"use_postmaster") == 0)
1541 verify_options |= vopt_callout_recippmaster;
1542 else if (strcmpic(opt, US"postmaster") == 0) pm_mailfrom = US"";
1543 else if (strcmpic(opt, US"fullpostmaster") == 0)
1546 verify_options |= vopt_callout_fullpm;
1549 else if (strncmpic(opt, US"mailfrom", 8) == 0)
1551 if (!verify_header_sender)
1553 *log_msgptr = string_sprintf("\"mailfrom\" is allowed as a "
1554 "callout option only for verify=header_sender (detected in ACL "
1555 "condition \"%s\")", arg);
1559 while (isspace(*opt)) opt++;
1562 *log_msgptr = string_sprintf("'=' expected after "
1563 "\"mailfrom\" in ACL condition \"%s\"", arg);
1566 while (isspace(*opt)) opt++;
1567 se_mailfrom = string_copy(opt);
1570 else if (strncmpic(opt, US"postmaster_mailfrom", 19) == 0)
1573 while (isspace(*opt)) opt++;
1576 *log_msgptr = string_sprintf("'=' expected after "
1577 "\"postmaster_mailfrom\" in ACL condition \"%s\"", arg);
1580 while (isspace(*opt)) opt++;
1581 pm_mailfrom = string_copy(opt);
1584 else if (strncmpic(opt, US"maxwait", 7) == 0)
1587 while (isspace(*opt)) opt++;
1590 *log_msgptr = string_sprintf("'=' expected after \"maxwait\" in "
1591 "ACL condition \"%s\"", arg);
1594 while (isspace(*opt)) opt++;
1595 callout_overall = readconf_readtime(opt, 0, FALSE);
1596 if (callout_overall < 0)
1598 *log_msgptr = string_sprintf("bad time value in ACL condition "
1599 "\"verify %s\"", arg);
1603 else if (strncmpic(opt, US"connect", 7) == 0)
1606 while (isspace(*opt)) opt++;
1609 *log_msgptr = string_sprintf("'=' expected after "
1610 "\"callout_overaall\" in ACL condition \"%s\"", arg);
1613 while (isspace(*opt)) opt++;
1614 callout_connect = readconf_readtime(opt, 0, FALSE);
1615 if (callout_connect < 0)
1617 *log_msgptr = string_sprintf("bad time value in ACL condition "
1618 "\"verify %s\"", arg);
1622 else /* Plain time is callout connect/command timeout */
1624 callout = readconf_readtime(opt, 0, FALSE);
1627 *log_msgptr = string_sprintf("bad time value in ACL condition "
1628 "\"verify %s\"", arg);
1636 *log_msgptr = string_sprintf("'=' expected after \"callout\" in "
1637 "ACL condition \"%s\"", arg);
1643 /* Option not recognized */
1647 *log_msgptr = string_sprintf("unknown option \"%s\" in ACL "
1648 "condition \"verify %s\"", ss, arg);
1653 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster)) ==
1654 (vopt_callout_recipsender|vopt_callout_recippmaster))
1656 *log_msgptr = US"only one of use_sender and use_postmaster can be set "
1657 "for a recipient callout";
1661 /* Handle sender-in-header verification. Default the user message to the log
1662 message if giving out verification details. */
1664 if (verify_header_sender)
1667 rc = verify_check_header_address(user_msgptr, log_msgptr, callout,
1668 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, verify_options,
1672 *basic_errno = verrno;
1673 if (smtp_return_error_details)
1675 if (*user_msgptr == NULL && *log_msgptr != NULL)
1676 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1677 if (rc == DEFER) acl_temp_details = TRUE;
1682 /* Handle a sender address. The default is to verify *the* sender address, but
1683 optionally a different address can be given, for special requirements. If the
1684 address is empty, we are dealing with a bounce message that has no sender, so
1685 we cannot do any checking. If the real sender address gets rewritten during
1686 verification (e.g. DNS widening), set the flag to stop it being rewritten again
1687 during message reception.
1689 A list of verified "sender" addresses is kept to try to avoid doing to much
1690 work repetitively when there are multiple recipients in a message and they all
1691 require sender verification. However, when callouts are involved, it gets too
1692 complicated because different recipients may require different callout options.
1693 Therefore, we always do a full sender verify when any kind of callout is
1694 specified. Caching elsewhere, for instance in the DNS resolver and in the
1695 callout handling, should ensure that this is not terribly inefficient. */
1697 else if (verify_sender_address != NULL)
1699 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster))
1702 *log_msgptr = US"use_sender or use_postmaster cannot be used for a "
1703 "sender verify callout";
1707 sender_vaddr = verify_checked_sender(verify_sender_address);
1708 if (sender_vaddr != NULL && /* Previously checked */
1709 callout <= 0) /* No callout needed this time */
1711 /* If the "routed" flag is set, it means that routing worked before, so
1712 this check can give OK (the saved return code value, if set, belongs to a
1713 callout that was done previously). If the "routed" flag is not set, routing
1714 must have failed, so we use the saved return code. */
1716 if (testflag(sender_vaddr, af_verify_routed)) rc = OK; else
1718 rc = sender_vaddr->special_action;
1719 *basic_errno = sender_vaddr->basic_errno;
1721 HDEBUG(D_acl) debug_printf("using cached sender verify result\n");
1724 /* Do a new verification, and cache the result. The cache is used to avoid
1725 verifying the sender multiple times for multiple RCPTs when callouts are not
1726 specified (see comments above).
1728 The cache is also used on failure to give details in response to the first
1729 RCPT that gets bounced for this reason. However, this can be suppressed by
1730 the no_details option, which sets the flag that says "this detail has already
1731 been sent". The cache normally contains just one address, but there may be
1732 more in esoteric circumstances. */
1737 uschar *save_address_data = deliver_address_data;
1739 sender_vaddr = deliver_make_addr(verify_sender_address, TRUE);
1740 if (no_details) setflag(sender_vaddr, af_sverify_told);
1741 if (verify_sender_address[0] != 0)
1743 /* If this is the real sender address, save the unrewritten version
1744 for use later in receive. Otherwise, set a flag so that rewriting the
1745 sender in verify_address() does not update sender_address. */
1747 if (verify_sender_address == sender_address)
1748 sender_address_unrewritten = sender_address;
1750 verify_options |= vopt_fake_sender;
1752 if (success_on_redirect)
1753 verify_options |= vopt_success_on_redirect;
1755 /* The recipient, qualify, and expn options are never set in
1758 rc = verify_address(sender_vaddr, NULL, verify_options, callout,
1759 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, &routed);
1761 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
1765 if (Ustrcmp(sender_vaddr->address, verify_sender_address) != 0)
1767 DEBUG(D_acl) debug_printf("sender %s verified ok as %s\n",
1768 verify_sender_address, sender_vaddr->address);
1772 DEBUG(D_acl) debug_printf("sender %s verified ok\n",
1773 verify_sender_address);
1776 else *basic_errno = sender_vaddr->basic_errno;
1778 else rc = OK; /* Null sender */
1780 /* Cache the result code */
1782 if (routed) setflag(sender_vaddr, af_verify_routed);
1783 if (callout > 0) setflag(sender_vaddr, af_verify_callout);
1784 sender_vaddr->special_action = rc;
1785 sender_vaddr->next = sender_verified_list;
1786 sender_verified_list = sender_vaddr;
1788 /* Restore the recipient address data, which might have been clobbered by
1789 the sender verification. */
1791 deliver_address_data = save_address_data;
1794 /* Put the sender address_data value into $sender_address_data */
1796 sender_address_data = sender_vaddr->p.address_data;
1799 /* A recipient address just gets a straightforward verify; again we must handle
1800 the DEFER overrides. */
1806 if (success_on_redirect)
1807 verify_options |= vopt_success_on_redirect;
1809 /* We must use a copy of the address for verification, because it might
1813 rc = verify_address(&addr2, NULL, verify_options|vopt_is_recipient, callout,
1814 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, NULL);
1815 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
1817 *log_msgptr = addr2.message;
1818 *user_msgptr = (addr2.user_message != NULL)?
1819 addr2.user_message : addr2.message;
1820 *basic_errno = addr2.basic_errno;
1822 /* Make $address_data visible */
1823 deliver_address_data = addr2.p.address_data;
1826 /* We have a result from the relevant test. Handle defer overrides first. */
1828 if (rc == DEFER && (defer_ok ||
1829 (callout_defer_ok && *basic_errno == ERRNO_CALLOUTDEFER)))
1831 HDEBUG(D_acl) debug_printf("verify defer overridden by %s\n",
1832 defer_ok? "defer_ok" : "callout_defer_ok");
1836 /* If we've failed a sender, set up a recipient message, and point
1837 sender_verified_failed to the address item that actually failed. */
1839 if (rc != OK && verify_sender_address != NULL)
1843 *log_msgptr = *user_msgptr = US"Sender verify failed";
1845 else if (*basic_errno != ERRNO_CALLOUTDEFER)
1847 *log_msgptr = *user_msgptr = US"Could not complete sender verify";
1851 *log_msgptr = US"Could not complete sender verify callout";
1852 *user_msgptr = smtp_return_error_details? sender_vaddr->user_message :
1856 sender_verified_failed = sender_vaddr;
1859 /* Verifying an address messes up the values of $domain and $local_part,
1860 so reset them before returning if this is a RCPT ACL. */
1864 deliver_domain = addr->domain;
1865 deliver_localpart = addr->local_part;
1869 /* Syntax errors in the verify argument come here. */
1872 *log_msgptr = string_sprintf("expected \"sender[=address]\", \"recipient\", "
1873 "\"helo\", \"header_syntax\", \"header_sender\" or "
1874 "\"reverse_host_lookup\" at start of ACL condition "
1875 "\"verify %s\"", arg);
1878 /* Options supplied when not allowed come here */
1881 *log_msgptr = string_sprintf("unexpected '/' found in \"%s\" "
1882 "(this verify item has no options)", arg);
1885 /* Calls in the wrong ACL come here */
1888 *log_msgptr = string_sprintf("cannot check header contents in ACL for %s "
1889 "(only possible in ACL for DATA)", acl_wherenames[where]);
1896 /*************************************************
1897 * Check argument for control= modifier *
1898 *************************************************/
1900 /* Called from acl_check_condition() below
1903 arg the argument string for control=
1904 pptr set to point to the terminating character
1905 where which ACL we are in
1906 log_msgptr for error messages
1908 Returns: CONTROL_xxx value
1912 decode_control(uschar *arg, uschar **pptr, int where, uschar **log_msgptr)
1917 for (d = controls_list;
1918 d < controls_list + sizeof(controls_list)/sizeof(control_def);
1921 len = Ustrlen(d->name);
1922 if (Ustrncmp(d->name, arg, len) == 0) break;
1925 if (d >= controls_list + sizeof(controls_list)/sizeof(control_def) ||
1926 (arg[len] != 0 && (!d->has_option || arg[len] != '/')))
1928 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
1929 return CONTROL_ERROR;
1938 /*************************************************
1939 * Handle rate limiting *
1940 *************************************************/
1942 /* Called by acl_check_condition() below to calculate the result
1943 of the ACL ratelimit condition.
1945 Note that the return value might be slightly unexpected: if the
1946 sender's rate is above the limit then the result is OK. This is
1947 similar to the dnslists condition, and is so that you can write
1948 ACL clauses like: defer ratelimit = 15 / 1h
1951 arg the option string for ratelimit=
1952 log_msgptr for error messages
1954 Returns: OK - Sender's rate is above limit
1955 FAIL - Sender's rate is below limit
1956 DEFER - Problem opening ratelimit database
1957 ERROR - Syntax error in options.
1961 acl_ratelimit(uschar *arg, uschar **log_msgptr)
1963 double limit, period;
1966 BOOL have_key = FALSE, leaky = FALSE, strict = FALSE;
1967 BOOL per_byte = FALSE, per_cmd = FALSE, per_conn = FALSE, per_mail = FALSE;
1969 tree_node **anchor, *t;
1970 open_db dbblock, *dbm;
1971 dbdata_ratelimit *dbd;
1974 /* Parse the first two options and record their values in expansion
1975 variables. These variables allow the configuration to have informative
1976 error messages based on rate limits obtained from a table lookup. */
1978 /* First is the maximum number of messages per period and maximum burst
1979 size, which must be greater than or equal to zero. Zero is useful for
1980 rate measurement as opposed to rate limiting. */
1982 sender_rate_limit = string_nextinlist(&arg, &sep, NULL, 0);
1983 if (sender_rate_limit == NULL)
1987 limit = Ustrtod(sender_rate_limit, &ss);
1988 if (tolower(*ss) == 'k') { limit *= 1024.0; ss++; }
1989 else if (tolower(*ss) == 'm') { limit *= 1024.0*1024.0; ss++; }
1990 else if (tolower(*ss) == 'g') { limit *= 1024.0*1024.0*1024.0; ss++; }
1992 if (limit < 0.0 || *ss != 0)
1994 *log_msgptr = string_sprintf("syntax error in argument for "
1995 "\"ratelimit\" condition: \"%s\" is not a positive number",
2000 /* We use the rest of the argument list following the limit as the
2001 lookup key, because it doesn't make sense to use the same stored data
2002 if the period or options are different. */
2006 /* Second is the rate measurement period and exponential smoothing time
2007 constant. This must be strictly greater than zero, because zero leads to
2008 run-time division errors. */
2010 sender_rate_period = string_nextinlist(&arg, &sep, NULL, 0);
2011 if (sender_rate_period == NULL) period = -1.0;
2012 else period = readconf_readtime(sender_rate_period, 0, FALSE);
2015 *log_msgptr = string_sprintf("syntax error in argument for "
2016 "\"ratelimit\" condition: \"%s\" is not a time value",
2017 sender_rate_period);
2021 /* Parse the other options. Should we check if the per_* options are being
2022 used in ACLs where they don't make sense, e.g. per_mail in the connect ACL? */
2024 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2027 if (strcmpic(ss, US"leaky") == 0) leaky = TRUE;
2028 else if (strcmpic(ss, US"strict") == 0) strict = TRUE;
2029 else if (strcmpic(ss, US"per_byte") == 0) per_byte = TRUE;
2030 else if (strcmpic(ss, US"per_cmd") == 0) per_cmd = TRUE;
2031 else if (strcmpic(ss, US"per_conn") == 0) per_conn = TRUE;
2032 else if (strcmpic(ss, US"per_mail") == 0) per_mail = TRUE;
2033 else if (strcmpic(ss, US"per_rcpt") == 0) per_cmd = TRUE; /* alias */
2034 else have_key = TRUE;
2036 if (leaky + strict > 1 || per_byte + per_cmd + per_conn + per_mail > 1)
2038 *log_msgptr = US"conflicting options for \"ratelimit\" condition";
2042 /* Default option values */
2043 if (!strict) leaky = TRUE;
2044 if (!per_byte && !per_cmd && !per_conn) per_mail = TRUE;
2046 /* If there is no explicit key, use the sender_host_address. If there is no
2047 sender_host_address (e.g. -bs or acl_not_smtp) then we simply omit it. */
2049 if (!have_key && sender_host_address != NULL)
2050 key = string_sprintf("%s / %s", key, sender_host_address);
2052 HDEBUG(D_acl) debug_printf("ratelimit condition limit=%.0f period=%.0f key=%s\n",
2053 limit, period, key);
2055 /* See if we have already computed the rate by looking in the relevant tree. For
2056 per-connection rate limiting, store tree nodes and dbdata in the permanent pool
2057 so that they survive across resets. */
2060 old_pool = store_pool;
2064 anchor = &ratelimiters_conn;
2065 store_pool = POOL_PERM;
2067 else if (per_mail || per_byte)
2068 anchor = &ratelimiters_mail;
2070 anchor = &ratelimiters_cmd;
2072 if (anchor != NULL && (t = tree_search(*anchor, key)) != NULL)
2075 /* The following few lines duplicate some of the code below. */
2076 if (dbd->rate < limit) rc = FAIL;
2078 store_pool = old_pool;
2079 sender_rate = string_sprintf("%.1f", dbd->rate);
2081 debug_printf("ratelimit found pre-computed rate %s\n", sender_rate);
2085 /* We aren't using a pre-computed rate, so get a previously recorded
2086 rate from the database, update it, and write it back. If there's no
2087 previous rate for this key, create one. */
2089 dbm = dbfn_open(US"ratelimit", O_RDWR, &dbblock, TRUE);
2092 store_pool = old_pool;
2094 HDEBUG(D_acl) debug_printf("ratelimit database not available\n");
2095 *log_msgptr = US"ratelimit database not available";
2098 dbd = dbfn_read(dbm, key);
2100 gettimeofday(&tv, NULL);
2104 HDEBUG(D_acl) debug_printf("ratelimit initializing new key's data\n");
2105 dbd = store_get(sizeof(dbdata_ratelimit));
2106 dbd->time_stamp = tv.tv_sec;
2107 dbd->time_usec = tv.tv_usec;
2112 /* The smoothed rate is computed using an exponentially weighted moving
2113 average adjusted for variable sampling intervals. The standard EWMA for
2114 a fixed sampling interval is: f'(t) = (1 - a) * f(t) + a * f'(t - 1)
2115 where f() is the measured value and f'() is the smoothed value.
2117 Old data decays out of the smoothed value exponentially, such that data n
2118 samples old is multiplied by a^n. The exponential decay time constant p
2119 is defined such that data p samples old is multiplied by 1/e, which means
2120 that a = exp(-1/p). We can maintain the same time constant for a variable
2121 sampling interval i by using a = exp(-i/p).
2123 The rate we are measuring is messages per period, suitable for directly
2124 comparing with the limit. The average rate between now and the previous
2125 message is period / interval, which we feed into the EWMA as the sample.
2127 It turns out that the number of messages required for the smoothed rate
2128 to reach the limit when they are sent in a burst is equal to the limit.
2129 This can be seen by analysing the value of the smoothed rate after N
2130 messages sent at even intervals. Let k = (1 - a) * p/i
2132 rate_1 = (1 - a) * p/i + a * rate_0
2134 rate_2 = k + a * rate_1
2135 = k + a * k + a^2 * rate_0
2136 rate_3 = k + a * k + a^2 * k + a^3 * rate_0
2137 rate_N = rate_0 * a^N + k * SUM(x=0..N-1)(a^x)
2138 = rate_0 * a^N + k * (1 - a^N) / (1 - a)
2139 = rate_0 * a^N + p/i * (1 - a^N)
2141 When N is large, a^N -> 0 so rate_N -> p/i as desired.
2143 rate_N = p/i + (rate_0 - p/i) * a^N
2144 a^N = (rate_N - p/i) / (rate_0 - p/i)
2145 N * -i/p = log((rate_N - p/i) / (rate_0 - p/i))
2146 N = p/i * log((rate_0 - p/i) / (rate_N - p/i))
2148 Numerical analysis of the above equation, setting the computed rate to
2149 increase from rate_0 = 0 to rate_N = limit, shows that for large sending
2150 rates, p/i, the number of messages N = limit. So limit serves as both the
2151 maximum rate measured in messages per period, and the maximum number of
2152 messages that can be sent in a fast burst. */
2154 double this_time = (double)tv.tv_sec
2155 + (double)tv.tv_usec / 1000000.0;
2156 double prev_time = (double)dbd->time_stamp
2157 + (double)dbd->time_usec / 1000000.0;
2158 double interval = this_time - prev_time;
2160 double i_over_p = interval / period;
2161 double a = exp(-i_over_p);
2163 /* We must avoid division by zero, and deal gracefully with the clock going
2164 backwards. If we blunder ahead when time is in reverse then the computed
2165 rate will become bogusly huge. Clamp i/p to a very small number instead. */
2167 if (i_over_p <= 0.0) i_over_p = 1e-9;
2169 dbd->time_stamp = tv.tv_sec;
2170 dbd->time_usec = tv.tv_usec;
2172 /* If we are measuring the rate in bytes per period, multiply the
2173 measured rate by the message size. If we don't know the message size
2174 then it's safe to just use a value of zero and let the recorded rate
2175 decay as if nothing happened. */
2178 dbd->rate = (message_size < 0 ? 0.0 : (double)message_size)
2179 * (1 - a) / i_over_p + a * dbd->rate;
2181 dbd->rate = (1 - a) / i_over_p + a * dbd->rate;
2184 /* Clients sending at the limit are considered to be over the limit. This
2185 matters for edge cases such the first message sent by a client (which gets
2186 the initial rate of 0.0) when the rate limit is zero (i.e. the client should
2187 be completely blocked). */
2189 if (dbd->rate < limit) rc = FAIL;
2192 /* Update the state if the rate is low or if we are being strict. If we
2193 are in leaky mode and the sender's rate is too high, we do not update
2194 the recorded rate in order to avoid an over-aggressive sender's retry
2195 rate preventing them from getting any email through. */
2197 if (rc == FAIL || !leaky)
2198 dbfn_write(dbm, key, dbd, sizeof(dbdata_ratelimit));
2201 /* Store the result in the tree for future reference, if necessary. */
2205 t = store_get(sizeof(tree_node) + Ustrlen(key));
2207 Ustrcpy(t->name, key);
2208 (void)tree_insertnode(anchor, t);
2211 /* We create the formatted version of the sender's rate very late in
2212 order to ensure that it is done using the correct storage pool. */
2214 store_pool = old_pool;
2215 sender_rate = string_sprintf("%.1f", dbd->rate);
2218 debug_printf("ratelimit computed rate %s\n", sender_rate);
2225 /*************************************************
2226 * Handle conditions/modifiers on an ACL item *
2227 *************************************************/
2229 /* Called from acl_check() below.
2233 cb ACL condition block - if NULL, result is OK
2234 where where called from
2235 addr the address being checked for RCPT, or NULL
2236 level the nesting level
2237 epp pointer to pass back TRUE if "endpass" encountered
2238 (applies only to "accept" and "discard")
2239 user_msgptr user message pointer
2240 log_msgptr log message pointer
2241 basic_errno pointer to where to put verify error
2243 Returns: OK - all conditions are met
2244 DISCARD - an "acl" condition returned DISCARD - only allowed
2245 for "accept" or "discard" verbs
2246 FAIL - at least one condition fails
2247 FAIL_DROP - an "acl" condition returned FAIL_DROP
2248 DEFER - can't tell at the moment (typically, lookup defer,
2249 but can be temporary callout problem)
2250 ERROR - ERROR from nested ACL or expansion failure or other
2255 acl_check_condition(int verb, acl_condition_block *cb, int where,
2256 address_item *addr, int level, BOOL *epp, uschar **user_msgptr,
2257 uschar **log_msgptr, int *basic_errno)
2259 uschar *user_message = NULL;
2260 uschar *log_message = NULL;
2263 #ifdef WITH_CONTENT_SCAN
2267 for (; cb != NULL; cb = cb->next)
2272 /* The message and log_message items set up messages to be used in
2273 case of rejection. They are expanded later. */
2275 if (cb->type == ACLC_MESSAGE)
2277 user_message = cb->arg;
2281 if (cb->type == ACLC_LOG_MESSAGE)
2283 log_message = cb->arg;
2287 /* The endpass "condition" just sets a flag to show it occurred. This is
2288 checked at compile time to be on an "accept" or "discard" item. */
2290 if (cb->type == ACLC_ENDPASS)
2296 /* For other conditions and modifiers, the argument is expanded now for some
2297 of them, but not for all, because expansion happens down in some lower level
2298 checking functions in some cases. */
2300 if (cond_expand_at_top[cb->type])
2302 arg = expand_string(cb->arg);
2305 if (expand_string_forcedfail) continue;
2306 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s",
2307 cb->arg, expand_string_message);
2308 return search_find_defer? DEFER : ERROR;
2313 /* Show condition, and expanded condition if it's different */
2318 debug_printf("check %s%s %n",
2319 (!cond_modifiers[cb->type] && cb->u.negated)? "!":"",
2320 conditions[cb->type], &lhswidth);
2322 if (cb->type == ACLC_SET)
2324 int n = cb->u.varnumber;
2325 int t = (n < ACL_C_MAX)? 'c' : 'm';
2326 if (n >= ACL_C_MAX) n -= ACL_C_MAX;
2327 debug_printf("acl_%c%d ", t, n);
2331 debug_printf("= %s\n", cb->arg);
2334 debug_printf("%.*s= %s\n", lhswidth,
2338 /* Check that this condition makes sense at this time */
2340 if ((cond_forbids[cb->type] & (1 << where)) != 0)
2342 *log_msgptr = string_sprintf("cannot %s %s condition in %s ACL",
2343 cond_modifiers[cb->type]? "use" : "test",
2344 conditions[cb->type], acl_wherenames[where]);
2348 /* Run the appropriate test for each condition, or take the appropriate
2349 action for the remaining modifiers. */
2353 /* A nested ACL that returns "discard" makes sense only for an "accept" or
2357 rc = acl_check_internal(where, addr, arg, level+1, user_msgptr, log_msgptr);
2358 if (rc == DISCARD && verb != ACL_ACCEPT && verb != ACL_DISCARD)
2360 *log_msgptr = string_sprintf("nested ACL returned \"discard\" for "
2361 "\"%s\" command (only allowed with \"accept\" or \"discard\")",
2367 case ACLC_AUTHENTICATED:
2368 rc = (sender_host_authenticated == NULL)? FAIL :
2369 match_isinlist(sender_host_authenticated, &arg, 0, NULL, NULL, MCL_STRING,
2373 #ifdef EXPERIMENTAL_BRIGHTMAIL
2374 case ACLC_BMI_OPTIN:
2376 int old_pool = store_pool;
2377 store_pool = POOL_PERM;
2378 bmi_current_optin = string_copy(arg);
2379 store_pool = old_pool;
2384 case ACLC_CONDITION:
2385 if (Ustrspn(arg, "0123456789") == Ustrlen(arg)) /* Digits, or empty */
2386 rc = (Uatoi(arg) == 0)? FAIL : OK;
2388 rc = (strcmpic(arg, US"no") == 0 ||
2389 strcmpic(arg, US"false") == 0)? FAIL :
2390 (strcmpic(arg, US"yes") == 0 ||
2391 strcmpic(arg, US"true") == 0)? OK : DEFER;
2393 *log_msgptr = string_sprintf("invalid \"condition\" value \"%s\"", arg);
2397 control_type = decode_control(arg, &p, where, log_msgptr);
2399 /* Check if this control makes sense at this time */
2401 if ((control_forbids[control_type] & (1 << where)) != 0)
2403 *log_msgptr = string_sprintf("cannot use \"control=%s\" in %s ACL",
2404 controls[control_type], acl_wherenames[where]);
2408 switch(control_type)
2410 #ifdef EXPERIMENTAL_BRIGHTMAIL
2411 case CONTROL_BMI_RUN:
2415 #ifdef EXPERIMENTAL_DOMAINKEYS
2416 case CONTROL_DK_VERIFY:
2423 case CONTROL_CASEFUL_LOCAL_PART:
2424 deliver_localpart = addr->cc_local_part;
2427 case CONTROL_CASELOWER_LOCAL_PART:
2428 deliver_localpart = addr->lc_local_part;
2431 case CONTROL_ENFORCE_SYNC:
2432 smtp_enforce_sync = TRUE;
2435 case CONTROL_NO_ENFORCE_SYNC:
2436 smtp_enforce_sync = FALSE;
2439 #ifdef WITH_CONTENT_SCAN
2440 case CONTROL_NO_MBOX_UNSPOOL:
2441 no_mbox_unspool = TRUE;
2445 case CONTROL_NO_MULTILINE:
2446 no_multiline_responses = TRUE;
2449 case CONTROL_FAKEDEFER:
2450 case CONTROL_FAKEREJECT:
2451 fake_response = (control_type == CONTROL_FAKEDEFER) ? DEFER : FAIL;
2455 while (*pp != 0) pp++;
2456 fake_response_text = expand_string(string_copyn(p+1, pp-p-1));
2461 /* Explicitly reset to default string */
2462 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).";
2466 case CONTROL_FREEZE:
2467 deliver_freeze = TRUE;
2468 deliver_frozen_at = time(NULL);
2471 case CONTROL_QUEUE_ONLY:
2472 queue_only_policy = TRUE;
2475 case CONTROL_SUBMISSION:
2476 originator_name = US"";
2477 submission_mode = TRUE;
2480 if (Ustrncmp(p, "/sender_retain", 14) == 0)
2483 active_local_sender_retain = TRUE;
2484 active_local_from_check = FALSE;
2486 else if (Ustrncmp(p, "/domain=", 8) == 0)
2489 while (*pp != 0 && *pp != '/') pp++;
2490 submission_domain = string_copyn(p+8, pp-p-8);
2493 else if (Ustrncmp(p, "/name=", 6) == 0)
2496 while (*pp != 0 && *pp != '/') pp++;
2497 originator_name = string_copy(parse_fix_phrase(p+6, pp-p-6,
2498 big_buffer, big_buffer_size));
2505 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
2512 #ifdef WITH_CONTENT_SCAN
2514 rc = mime_decode(&arg);
2520 int delay = readconf_readtime(arg, 0, FALSE);
2523 *log_msgptr = string_sprintf("syntax error in argument for \"delay\" "
2524 "modifier: \"%s\" is not a time value", arg);
2529 HDEBUG(D_acl) debug_printf("delay modifier requests %d-second delay\n",
2534 debug_printf("delay skipped in -bh checking mode\n");
2537 /* It appears to be impossible to detect that a TCP/IP connection has
2538 gone away without reading from it. This means that we cannot shorten
2539 the delay below if the client goes away, because we cannot discover
2540 that the client has closed its end of the connection. (The connection
2541 is actually in a half-closed state, waiting for the server to close its
2542 end.) It would be nice to be able to detect this state, so that the
2543 Exim process is not held up unnecessarily. However, it seems that we
2544 can't. The poll() function does not do the right thing, and in any case
2545 it is not always available.
2547 NOTE: If ever this state of affairs changes, remember that we may be
2548 dealing with stdin/stdout here, in addition to TCP/IP connections.
2549 Whatever is done must work in both cases. To detected the stdin/stdout
2550 case, check for smtp_in or smtp_out being NULL. */
2554 while (delay > 0) delay = sleep(delay);
2560 #ifdef WITH_OLD_DEMIME
2566 #ifdef EXPERIMENTAL_DOMAINKEYS
2567 case ACLC_DK_DOMAIN_SOURCE:
2568 if (dk_verify_block == NULL) { rc = FAIL; break; };
2569 /* check header source of domain against given string */
2570 switch (dk_verify_block->address_source) {
2571 case DK_EXIM_ADDRESS_FROM_FROM:
2572 rc = match_isinlist(US"from", &arg, 0, NULL,
2573 NULL, MCL_STRING, TRUE, NULL);
2575 case DK_EXIM_ADDRESS_FROM_SENDER:
2576 rc = match_isinlist(US"sender", &arg, 0, NULL,
2577 NULL, MCL_STRING, TRUE, NULL);
2579 case DK_EXIM_ADDRESS_NONE:
2580 rc = match_isinlist(US"none", &arg, 0, NULL,
2581 NULL, MCL_STRING, TRUE, NULL);
2585 case ACLC_DK_POLICY:
2586 if (dk_verify_block == NULL) { rc = FAIL; break; };
2587 /* check policy against given string, default FAIL */
2589 if (dk_verify_block->signsall)
2590 rc = match_isinlist(US"signsall", &arg, 0, NULL,
2591 NULL, MCL_STRING, TRUE, NULL);
2592 if (dk_verify_block->testing)
2593 rc = match_isinlist(US"testing", &arg, 0, NULL,
2594 NULL, MCL_STRING, TRUE, NULL);
2596 case ACLC_DK_SENDER_DOMAINS:
2597 if (dk_verify_block == NULL) { rc = FAIL; break; };
2598 if (dk_verify_block->domain != NULL)
2599 rc = match_isinlist(dk_verify_block->domain, &arg, 0, &domainlist_anchor,
2600 NULL, MCL_DOMAIN, TRUE, NULL);
2603 case ACLC_DK_SENDER_LOCAL_PARTS:
2604 if (dk_verify_block == NULL) { rc = FAIL; break; };
2605 if (dk_verify_block->local_part != NULL)
2606 rc = match_isinlist(dk_verify_block->local_part, &arg, 0, &localpartlist_anchor,
2607 NULL, MCL_LOCALPART, TRUE, NULL);
2610 case ACLC_DK_SENDERS:
2611 if (dk_verify_block == NULL) { rc = FAIL; break; };
2612 if (dk_verify_block->address != NULL)
2613 rc = match_address_list(dk_verify_block->address, TRUE, TRUE, &arg, NULL, -1, 0, NULL);
2616 case ACLC_DK_STATUS:
2617 if (dk_verify_block == NULL) { rc = FAIL; break; };
2618 if (dk_verify_block->result > 0) {
2619 switch(dk_verify_block->result) {
2620 case DK_EXIM_RESULT_BAD_FORMAT:
2621 rc = match_isinlist(US"bad format", &arg, 0, NULL,
2622 NULL, MCL_STRING, TRUE, NULL);
2624 case DK_EXIM_RESULT_NO_KEY:
2625 rc = match_isinlist(US"no key", &arg, 0, NULL,
2626 NULL, MCL_STRING, TRUE, NULL);
2628 case DK_EXIM_RESULT_NO_SIGNATURE:
2629 rc = match_isinlist(US"no signature", &arg, 0, NULL,
2630 NULL, MCL_STRING, TRUE, NULL);
2632 case DK_EXIM_RESULT_REVOKED:
2633 rc = match_isinlist(US"revoked", &arg, 0, NULL,
2634 NULL, MCL_STRING, TRUE, NULL);
2636 case DK_EXIM_RESULT_NON_PARTICIPANT:
2637 rc = match_isinlist(US"non-participant", &arg, 0, NULL,
2638 NULL, MCL_STRING, TRUE, NULL);
2640 case DK_EXIM_RESULT_GOOD:
2641 rc = match_isinlist(US"good", &arg, 0, NULL,
2642 NULL, MCL_STRING, TRUE, NULL);
2644 case DK_EXIM_RESULT_BAD:
2645 rc = match_isinlist(US"bad", &arg, 0, NULL,
2646 NULL, MCL_STRING, TRUE, NULL);
2654 rc = verify_check_dnsbl(&arg);
2658 rc = match_isinlist(addr->domain, &arg, 0, &domainlist_anchor,
2659 addr->domain_cache, MCL_DOMAIN, TRUE, &deliver_domain_data);
2662 /* The value in tls_cipher is the full cipher name, for example,
2663 TLSv1:DES-CBC3-SHA:168, whereas the values to test for are just the
2664 cipher names such as DES-CBC3-SHA. But program defensively. We don't know
2665 what may in practice come out of the SSL library - which at the time of
2666 writing is poorly documented. */
2668 case ACLC_ENCRYPTED:
2669 if (tls_cipher == NULL) rc = FAIL; else
2671 uschar *endcipher = NULL;
2672 uschar *cipher = Ustrchr(tls_cipher, ':');
2673 if (cipher == NULL) cipher = tls_cipher; else
2675 endcipher = Ustrchr(++cipher, ':');
2676 if (endcipher != NULL) *endcipher = 0;
2678 rc = match_isinlist(cipher, &arg, 0, NULL, NULL, MCL_STRING, TRUE, NULL);
2679 if (endcipher != NULL) *endcipher = ':';
2683 /* Use verify_check_this_host() instead of verify_check_host() so that
2684 we can pass over &host_data to catch any looked up data. Once it has been
2685 set, it retains its value so that it's still there if another ACL verb
2686 comes through here and uses the cache. However, we must put it into
2687 permanent store in case it is also expected to be used in a subsequent
2688 message in the same SMTP connection. */
2691 rc = verify_check_this_host(&arg, sender_host_cache, NULL,
2692 (sender_host_address == NULL)? US"" : sender_host_address, &host_data);
2693 if (host_data != NULL) host_data = string_copy_malloc(host_data);
2696 case ACLC_LOCAL_PARTS:
2697 rc = match_isinlist(addr->cc_local_part, &arg, 0,
2698 &localpartlist_anchor, addr->localpart_cache, MCL_LOCALPART, TRUE,
2699 &deliver_localpart_data);
2711 if (Ustrncmp(s, "main", 4) == 0)
2712 { logbits |= LOG_MAIN; s += 4; }
2713 else if (Ustrncmp(s, "panic", 5) == 0)
2714 { logbits |= LOG_PANIC; s += 5; }
2715 else if (Ustrncmp(s, "reject", 6) == 0)
2716 { logbits |= LOG_REJECT; s += 6; }
2719 logbits = LOG_MAIN|LOG_PANIC;
2720 s = string_sprintf(":unknown log name in \"%s\" in "
2721 "\"logwrite\" in %s ACL", arg, acl_wherenames[where]);
2727 while (isspace(*s)) s++;
2728 if (logbits == 0) logbits = LOG_MAIN;
2729 log_write(0, logbits, "%s", string_printing(s));
2733 #ifdef WITH_CONTENT_SCAN
2736 /* Seperate the regular expression and any optional parameters. */
2737 uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size);
2738 /* Run the malware backend. */
2740 /* Modify return code based upon the existance of options. */
2741 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2743 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
2745 /* FAIL so that the message is passed to the next ACL */
2752 case ACLC_MIME_REGEX:
2753 rc = mime_regex(&arg);
2757 case ACLC_RATELIMIT:
2758 rc = acl_ratelimit(arg, log_msgptr);
2761 case ACLC_RECIPIENTS:
2762 rc = match_address_list(addr->address, TRUE, TRUE, &arg, NULL, -1, 0,
2766 #ifdef WITH_CONTENT_SCAN
2772 case ACLC_SENDER_DOMAINS:
2775 sdomain = Ustrrchr(sender_address, '@');
2776 sdomain = (sdomain == NULL)? US"" : sdomain + 1;
2777 rc = match_isinlist(sdomain, &arg, 0, &domainlist_anchor,
2778 sender_domain_cache, MCL_DOMAIN, TRUE, NULL);
2783 rc = match_address_list(sender_address, TRUE, TRUE, &arg,
2784 sender_address_cache, -1, 0, &sender_data);
2787 /* Connection variables must persist forever */
2791 int old_pool = store_pool;
2792 if (cb->u.varnumber < ACL_C_MAX) store_pool = POOL_PERM;
2793 acl_var[cb->u.varnumber] = string_copy(arg);
2794 store_pool = old_pool;
2798 #ifdef WITH_CONTENT_SCAN
2801 /* Seperate the regular expression and any optional parameters. */
2802 uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size);
2803 /* Run the spam backend. */
2805 /* Modify return code based upon the existance of options. */
2806 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2808 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
2810 /* FAIL so that the message is passed to the next ACL */
2818 #ifdef EXPERIMENTAL_SPF
2820 rc = spf_process(&arg, sender_address);
2824 /* If the verb is WARN, discard any user message from verification, because
2825 such messages are SMTP responses, not header additions. The latter come
2826 only from explicit "message" modifiers. However, put the user message into
2827 $acl_verify_message so it can be used in subsequent conditions or modifiers
2828 (until something changes it). */
2831 rc = acl_verify(where, addr, arg, user_msgptr, log_msgptr, basic_errno);
2832 acl_verify_message = *user_msgptr;
2833 if (verb == ACL_WARN) *user_msgptr = NULL;
2837 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown "
2838 "condition %d", cb->type);
2842 /* If a condition was negated, invert OK/FAIL. */
2844 if (!cond_modifiers[cb->type] && cb->u.negated)
2846 if (rc == OK) rc = FAIL;
2847 else if (rc == FAIL || rc == FAIL_DROP) rc = OK;
2850 if (rc != OK) break; /* Conditions loop */
2854 /* If the result is the one for which "message" and/or "log_message" are used,
2855 handle the values of these options. Most verbs have but a single return for
2856 which the messages are relevant, but for "discard", it's useful to have the log
2857 message both when it succeeds and when it fails. Also, for an "accept" that
2858 appears in a QUIT ACL, we want to handle the user message. Since only "accept"
2859 and "warn" are permitted in that ACL, we don't need to test the verb.
2861 These modifiers act in different ways:
2863 "message" is a user message that will be included in an SMTP response. Unless
2864 it is empty, it overrides any previously set user message.
2866 "log_message" is a non-user message, and it adds to any existing non-user
2867 message that is already set.
2869 If there isn't a log message set, we make it the same as the user message. */
2871 if (((rc == FAIL_DROP)? FAIL : rc) == msgcond[verb] ||
2872 (verb == ACL_DISCARD && rc == OK) ||
2873 (where == ACL_WHERE_QUIT))
2877 /* If the verb is "warn", messages generated by conditions (verification or
2878 nested ACLs) are discarded. Only messages specified at this level are used.
2879 However, the value of an existing message is available in $acl_verify_message
2880 during expansions. */
2882 uschar *old_user_msgptr = *user_msgptr;
2883 uschar *old_log_msgptr = (*log_msgptr != NULL)? *log_msgptr : old_user_msgptr;
2885 if (verb == ACL_WARN) *log_msgptr = *user_msgptr = NULL;
2887 if (user_message != NULL)
2889 acl_verify_message = old_user_msgptr;
2890 expmessage = expand_string(user_message);
2891 if (expmessage == NULL)
2893 if (!expand_string_forcedfail)
2894 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
2895 user_message, expand_string_message);
2897 else if (expmessage[0] != 0) *user_msgptr = expmessage;
2900 if (log_message != NULL)
2902 acl_verify_message = old_log_msgptr;
2903 expmessage = expand_string(log_message);
2904 if (expmessage == NULL)
2906 if (!expand_string_forcedfail)
2907 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
2908 log_message, expand_string_message);
2910 else if (expmessage[0] != 0)
2912 *log_msgptr = (*log_msgptr == NULL)? expmessage :
2913 string_sprintf("%s: %s", expmessage, *log_msgptr);
2917 /* If no log message, default it to the user message */
2919 if (*log_msgptr == NULL) *log_msgptr = *user_msgptr;
2922 acl_verify_message = NULL;
2930 /*************************************************
2931 * Get line from a literal ACL *
2932 *************************************************/
2934 /* This function is passed to acl_read() in order to extract individual lines
2935 of a literal ACL, which we access via static pointers. We can destroy the
2936 contents because this is called only once (the compiled ACL is remembered).
2938 This code is intended to treat the data in the same way as lines in the main
2939 Exim configuration file. That is:
2941 . Leading spaces are ignored.
2943 . A \ at the end of a line is a continuation - trailing spaces after the \
2944 are permitted (this is because I don't believe in making invisible things
2945 significant). Leading spaces on the continued part of a line are ignored.
2947 . Physical lines starting (significantly) with # are totally ignored, and
2948 may appear within a sequence of backslash-continued lines.
2950 . Blank lines are ignored, but will end a sequence of continuations.
2953 Returns: a pointer to the next line
2957 static uschar *acl_text; /* Current pointer in the text */
2958 static uschar *acl_text_end; /* Points one past the terminating '0' */
2966 /* This loop handles leading blank lines and comments. */
2970 while (isspace(*acl_text)) acl_text++; /* Leading spaces/empty lines */
2971 if (*acl_text == 0) return NULL; /* No more data */
2972 yield = acl_text; /* Potential data line */
2974 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
2976 /* If we hit the end before a newline, we have the whole logical line. If
2977 it's a comment, there's no more data to be given. Otherwise, yield it. */
2979 if (*acl_text == 0) return (*yield == '#')? NULL : yield;
2981 /* After reaching a newline, end this loop if the physical line does not
2982 start with '#'. If it does, it's a comment, and the loop continues. */
2984 if (*yield != '#') break;
2987 /* This loop handles continuations. We know we have some real data, ending in
2988 newline. See if there is a continuation marker at the end (ignoring trailing
2989 white space). We know that *yield is not white space, so no need to test for
2990 cont > yield in the backwards scanning loop. */
2995 for (cont = acl_text - 1; isspace(*cont); cont--);
2997 /* If no continuation follows, we are done. Mark the end of the line and
3006 /* We have encountered a continuation. Skip over whitespace at the start of
3007 the next line, and indeed the whole of the next line or lines if they are
3012 while (*(++acl_text) == ' ' || *acl_text == '\t');
3013 if (*acl_text != '#') break;
3014 while (*(++acl_text) != 0 && *acl_text != '\n');
3017 /* We have the start of a continuation line. Move all the rest of the data
3018 to join onto the previous line, and then find its end. If the end is not a
3019 newline, we are done. Otherwise loop to look for another continuation. */
3021 memmove(cont, acl_text, acl_text_end - acl_text);
3022 acl_text_end -= acl_text - cont;
3024 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3025 if (*acl_text == 0) return yield;
3028 /* Control does not reach here */
3035 /*************************************************
3036 * Check access using an ACL *
3037 *************************************************/
3039 /* This function is called from address_check. It may recurse via
3040 acl_check_condition() - hence the use of a level to stop looping. The ACL is
3041 passed as a string which is expanded. A forced failure implies no access check
3042 is required. If the result is a single word, it is taken as the name of an ACL
3043 which is sought in the global ACL tree. Otherwise, it is taken as literal ACL
3044 text, complete with newlines, and parsed as such. In both cases, the ACL check
3045 is then run. This function uses an auxiliary function for acl_read() to call
3046 for reading individual lines of a literal ACL. This is acl_getline(), which
3047 appears immediately above.
3050 where where called from
3051 addr address item when called from RCPT; otherwise NULL
3052 s the input string; NULL is the same as an empty ACL => DENY
3053 level the nesting level
3054 user_msgptr where to put a user error (for SMTP response)
3055 log_msgptr where to put a logging message (not for SMTP response)
3057 Returns: OK access is granted
3058 DISCARD access is apparently granted...
3059 FAIL access is denied
3060 FAIL_DROP access is denied; drop the connection
3061 DEFER can't tell at the moment
3066 acl_check_internal(int where, address_item *addr, uschar *s, int level,
3067 uschar **user_msgptr, uschar **log_msgptr)
3070 acl_block *acl = NULL;
3071 uschar *acl_name = US"inline ACL";
3074 /* Catch configuration loops */
3078 *log_msgptr = US"ACL nested too deep: possible loop";
3084 HDEBUG(D_acl) debug_printf("ACL is NULL: implicit DENY\n");
3088 /* At top level, we expand the incoming string. At lower levels, it has already
3089 been expanded as part of condition processing. */
3093 ss = expand_string(s);
3096 if (expand_string_forcedfail) return OK;
3097 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s", s,
3098 expand_string_message);
3104 while (isspace(*ss))ss++;
3106 /* If we can't find a named ACL, the default is to parse it as an inline one.
3107 (Unless it begins with a slash; non-existent files give rise to an error.) */
3111 /* Handle the case of a string that does not contain any spaces. Look for a
3112 named ACL among those read from the configuration, or a previously read file.
3113 It is possible that the pointer to the ACL is NULL if the configuration
3114 contains a name with no data. If not found, and the text begins with '/',
3115 read an ACL from a file, and save it so it can be re-used. */
3117 if (Ustrchr(ss, ' ') == NULL)
3119 tree_node *t = tree_search(acl_anchor, ss);
3122 acl = (acl_block *)(t->data.ptr);
3125 HDEBUG(D_acl) debug_printf("ACL \"%s\" is empty: implicit DENY\n", ss);
3128 acl_name = string_sprintf("ACL \"%s\"", ss);
3129 HDEBUG(D_acl) debug_printf("using ACL \"%s\"\n", ss);
3132 else if (*ss == '/')
3134 struct stat statbuf;
3135 fd = Uopen(ss, O_RDONLY, 0);
3138 *log_msgptr = string_sprintf("failed to open ACL file \"%s\": %s", ss,
3143 if (fstat(fd, &statbuf) != 0)
3145 *log_msgptr = string_sprintf("failed to fstat ACL file \"%s\": %s", ss,
3150 acl_text = store_get(statbuf.st_size + 1);
3151 acl_text_end = acl_text + statbuf.st_size + 1;
3153 if (read(fd, acl_text, statbuf.st_size) != statbuf.st_size)
3155 *log_msgptr = string_sprintf("failed to read ACL file \"%s\": %s",
3156 ss, strerror(errno));
3159 acl_text[statbuf.st_size] = 0;
3162 acl_name = string_sprintf("ACL \"%s\"", ss);
3163 HDEBUG(D_acl) debug_printf("read ACL from file %s\n", ss);
3167 /* Parse an ACL that is still in text form. If it came from a file, remember it
3168 in the ACL tree, having read it into the POOL_PERM store pool so that it
3169 persists between multiple messages. */
3173 int old_pool = store_pool;
3174 if (fd >= 0) store_pool = POOL_PERM;
3175 acl = acl_read(acl_getline, log_msgptr);
3176 store_pool = old_pool;
3177 if (acl == NULL && *log_msgptr != NULL) return ERROR;
3180 tree_node *t = store_get_perm(sizeof(tree_node) + Ustrlen(ss));
3181 Ustrcpy(t->name, ss);
3183 (void)tree_insertnode(&acl_anchor, t);
3187 /* Now we have an ACL to use. It's possible it may be NULL. */
3192 int basic_errno = 0;
3193 BOOL endpass_seen = FALSE;
3195 *log_msgptr = *user_msgptr = NULL;
3196 acl_temp_details = FALSE;
3198 if (where == ACL_WHERE_QUIT &&
3199 acl->verb != ACL_ACCEPT &&
3200 acl->verb != ACL_WARN)
3202 *log_msgptr = string_sprintf("\"%s\" is not allowed in a QUIT ACL",
3207 HDEBUG(D_acl) debug_printf("processing \"%s\"\n", verbs[acl->verb]);
3209 /* Clear out any search error message from a previous check before testing
3212 search_error_message = NULL;
3213 cond = acl_check_condition(acl->verb, acl->condition, where, addr, level,
3214 &endpass_seen, user_msgptr, log_msgptr, &basic_errno);
3216 /* Handle special returns: DEFER causes a return except on a WARN verb;
3217 ERROR always causes a return. */
3222 HDEBUG(D_acl) debug_printf("%s: condition test deferred\n", verbs[acl->verb]);
3223 if (basic_errno != ERRNO_CALLOUTDEFER)
3225 if (search_error_message != NULL && *search_error_message != 0)
3226 *log_msgptr = search_error_message;
3227 if (smtp_return_error_details) acl_temp_details = TRUE;
3231 acl_temp_details = TRUE;
3233 if (acl->verb != ACL_WARN) return DEFER;
3236 default: /* Paranoia */
3238 HDEBUG(D_acl) debug_printf("%s: condition test error\n", verbs[acl->verb]);
3242 HDEBUG(D_acl) debug_printf("%s: condition test succeeded\n",
3247 HDEBUG(D_acl) debug_printf("%s: condition test failed\n", verbs[acl->verb]);
3250 /* DISCARD and DROP can happen only from a nested ACL condition, and
3251 DISCARD can happen only for an "accept" or "discard" verb. */
3254 HDEBUG(D_acl) debug_printf("%s: condition test yielded \"discard\"\n",
3259 HDEBUG(D_acl) debug_printf("%s: condition test yielded \"drop\"\n",
3264 /* At this point, cond for most verbs is either OK or FAIL or (as a result of
3265 a nested ACL condition) FAIL_DROP. However, for WARN, cond may be DEFER, and
3266 for ACCEPT and DISCARD, it may be DISCARD after a nested ACL call. */
3271 if (cond == OK || cond == DISCARD) return cond;
3274 HDEBUG(D_acl) debug_printf("accept: endpass encountered - denying access\n");
3282 acl_temp_details = TRUE;
3288 if (cond == OK) return FAIL;
3292 if (cond == OK || cond == DISCARD) return DISCARD;
3295 HDEBUG(D_acl) debug_printf("discard: endpass encountered - denying access\n");
3301 if (cond == OK) return FAIL_DROP;
3305 if (cond != OK) return cond;
3310 acl_warn(where, *user_msgptr, *log_msgptr);
3311 else if (cond == DEFER)
3312 log_write(0, LOG_MAIN, "%s Warning: ACL \"warn\" statement skipped: "
3313 "condition test deferred%s%s", host_and_ident(TRUE),
3314 (*log_msgptr == NULL)? US"" : US": ",
3315 (*log_msgptr == NULL)? US"" : *log_msgptr);
3316 *log_msgptr = *user_msgptr = NULL; /* In case implicit DENY follows */
3320 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown verb %d",
3325 /* Pass to the next ACL item */
3330 /* We have reached the end of the ACL. This is an implicit DENY. */
3332 HDEBUG(D_acl) debug_printf("end of %s: implicit DENY\n", acl_name);
3337 /*************************************************
3338 * Check access using an ACL *
3339 *************************************************/
3341 /* This is the external interface for ACL checks. It sets up an address and the
3342 expansions for $domain and $local_part when called after RCPT, then calls
3343 acl_check_internal() to do the actual work.
3346 where ACL_WHERE_xxxx indicating where called from
3347 recipient RCPT address for RCPT check, else NULL
3348 s the input string; NULL is the same as an empty ACL => DENY
3349 user_msgptr where to put a user error (for SMTP response)
3350 log_msgptr where to put a logging message (not for SMTP response)
3352 Returns: OK access is granted by an ACCEPT verb
3353 DISCARD access is granted by a DISCARD verb
3354 FAIL access is denied
3355 FAIL_DROP access is denied; drop the connection
3356 DEFER can't tell at the moment
3361 acl_check(int where, uschar *recipient, uschar *s, uschar **user_msgptr,
3362 uschar **log_msgptr)
3366 address_item *addr = NULL;
3368 *user_msgptr = *log_msgptr = NULL;
3369 sender_verified_failed = NULL;
3370 ratelimiters_cmd = NULL;
3372 if (where == ACL_WHERE_RCPT)
3374 adb = address_defaults;
3376 addr->address = recipient;
3377 if (deliver_split_address(addr) == DEFER)
3379 *log_msgptr = US"defer in percent_hack_domains check";
3382 deliver_domain = addr->domain;
3383 deliver_localpart = addr->local_part;
3386 rc = acl_check_internal(where, addr, s, 0, user_msgptr, log_msgptr);
3388 deliver_domain = deliver_localpart = deliver_address_data =
3389 sender_address_data = NULL;
3391 /* A DISCARD response is permitted only for message ACLs, excluding the PREDATA
3392 ACL, which is really in the middle of an SMTP command. */
3396 if (where > ACL_WHERE_NOTSMTP || where == ACL_WHERE_PREDATA)
3398 log_write(0, LOG_MAIN|LOG_PANIC, "\"discard\" verb not allowed in %s "
3399 "ACL", acl_wherenames[where]);
3405 /* A DROP response is not permitted from MAILAUTH */
3407 if (rc == FAIL_DROP && where == ACL_WHERE_MAILAUTH)
3409 log_write(0, LOG_MAIN|LOG_PANIC, "\"drop\" verb not allowed in %s "
3410 "ACL", acl_wherenames[where]);
3414 /* Before giving an error response, take a look at the length of any user
3415 message, and split it up into multiple lines if possible. */
3417 if (rc != OK && *user_msgptr != NULL && Ustrlen(*user_msgptr) > 75)
3419 uschar *s = *user_msgptr = string_copy(*user_msgptr);
3425 while (i < 75 && *ss != 0 && *ss != '\n') ss++, i++;
3426 if (*ss == 0) break;
3433 while (--t > s + 35)
3437 if (t[-1] == ':') { tt = t; break; }
3438 if (tt == NULL) tt = t;
3442 if (tt == NULL) /* Can't split behind - try ahead */
3447 if (*t == ' ' || *t == '\n')
3453 if (tt == NULL) break; /* Can't find anywhere to split */