1 /* $Cambridge: exim/src/src/acl.c,v 1.59 2006/06/07 15:06:26 fanf2 Exp $ */
3 /*************************************************
4 * Exim - an Internet mail transport agent *
5 *************************************************/
7 /* Copyright (c) University of Cambridge 1995 - 2006 */
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
35 follows, and the cond_expand_at_top and uschar cond_modifiers tables lower
41 #ifdef EXPERIMENTAL_BRIGHTMAIL
46 #ifdef WITH_CONTENT_SCAN
50 #ifdef WITH_OLD_DEMIME
53 #ifdef EXPERIMENTAL_DOMAINKEYS
54 ACLC_DK_DOMAIN_SOURCE,
56 ACLC_DK_SENDER_DOMAINS,
57 ACLC_DK_SENDER_LOCAL_PARTS,
69 #ifdef WITH_CONTENT_SCAN
73 #ifdef WITH_CONTENT_SCAN
78 #ifdef WITH_CONTENT_SCAN
84 #ifdef WITH_CONTENT_SCAN
87 #ifdef EXPERIMENTAL_SPF
92 /* ACL conditions/modifiers: "delay", "control", "endpass", "message",
93 "log_message", "logwrite", and "set" are modifiers that look like conditions
94 but always return TRUE. They are used for their side effects. */
96 static uschar *conditions[] = {
100 #ifdef EXPERIMENTAL_BRIGHTMAIL
105 #ifdef WITH_CONTENT_SCAN
109 #ifdef WITH_OLD_DEMIME
112 #ifdef EXPERIMENTAL_DOMAINKEYS
113 US"dk_domain_source",
115 US"dk_sender_domains",
116 US"dk_sender_local_parts",
120 US"dnslists", US"domains", US"encrypted",
121 US"endpass", US"hosts", US"local_parts", US"log_message", US"logwrite",
122 #ifdef WITH_CONTENT_SCAN
126 #ifdef WITH_CONTENT_SCAN
131 #ifdef WITH_CONTENT_SCAN
134 US"sender_domains", US"senders", US"set",
135 #ifdef WITH_CONTENT_SCAN
138 #ifdef EXPERIMENTAL_SPF
144 /* Return values from decode_control(); keep in step with the table of names
148 CONTROL_AUTH_UNADVERTISED,
149 #ifdef EXPERIMENTAL_BRIGHTMAIL
152 #ifdef EXPERIMENTAL_DOMAINKEYS
156 CONTROL_CASEFUL_LOCAL_PART,
157 CONTROL_CASELOWER_LOCAL_PART,
158 CONTROL_ENFORCE_SYNC,
159 CONTROL_NO_ENFORCE_SYNC,
163 CONTROL_SUPPRESS_LOCAL_FIXUPS,
164 #ifdef WITH_CONTENT_SCAN
165 CONTROL_NO_MBOX_UNSPOOL,
172 /* ACL control names; keep in step with the table above! This list is used for
173 turning ids into names. The actual list of recognized names is in the variable
174 control_def controls_list[] below. The fact that there are two lists is a mess
175 and should be tidied up. */
177 static uschar *controls[] = {
178 US"allow_auth_unadvertised",
179 #ifdef EXPERIMENTAL_BRIGHTMAIL
182 #ifdef EXPERIMENTAL_DOMAINKEYS
186 US"caseful_local_part",
187 US"caselower_local_part",
193 US"suppress_local_fixups",
194 #ifdef WITH_CONTENT_SCAN
200 /* Flags to indicate for which conditions /modifiers a string expansion is done
201 at the outer level. In the other cases, expansion already occurs in the
202 checking functions. */
204 static uschar cond_expand_at_top[] = {
206 TRUE, /* add_header */
207 FALSE, /* authenticated */
208 #ifdef EXPERIMENTAL_BRIGHTMAIL
209 TRUE, /* bmi_optin */
211 TRUE, /* condition */
213 #ifdef WITH_CONTENT_SCAN
217 #ifdef WITH_OLD_DEMIME
220 #ifdef EXPERIMENTAL_DOMAINKEYS
221 TRUE, /* dk_domain_source */
222 TRUE, /* dk_policy */
223 TRUE, /* dk_sender_domains */
224 TRUE, /* dk_sender_local_parts */
225 TRUE, /* dk_senders */
226 TRUE, /* dk_status */
230 FALSE, /* encrypted */
233 FALSE, /* local_parts */
234 TRUE, /* log_message */
236 #ifdef WITH_CONTENT_SCAN
240 #ifdef WITH_CONTENT_SCAN
241 TRUE, /* mime_regex */
243 TRUE, /* ratelimit */
244 FALSE, /* recipients */
245 #ifdef WITH_CONTENT_SCAN
248 FALSE, /* sender_domains */
251 #ifdef WITH_CONTENT_SCAN
254 #ifdef EXPERIMENTAL_SPF
260 /* Flags to identify the modifiers */
262 static uschar cond_modifiers[] = {
264 TRUE, /* add_header */
265 FALSE, /* authenticated */
266 #ifdef EXPERIMENTAL_BRIGHTMAIL
267 TRUE, /* bmi_optin */
269 FALSE, /* condition */
271 #ifdef WITH_CONTENT_SCAN
275 #ifdef WITH_OLD_DEMIME
278 #ifdef EXPERIMENTAL_DOMAINKEYS
279 FALSE, /* dk_domain_source */
280 FALSE, /* dk_policy */
281 FALSE, /* dk_sender_domains */
282 FALSE, /* dk_sender_local_parts */
283 FALSE, /* dk_senders */
284 FALSE, /* dk_status */
286 FALSE, /* dnslists */
288 FALSE, /* encrypted */
291 FALSE, /* local_parts */
292 TRUE, /* log_message */
294 #ifdef WITH_CONTENT_SCAN
298 #ifdef WITH_CONTENT_SCAN
299 FALSE, /* mime_regex */
301 FALSE, /* ratelimit */
302 FALSE, /* recipients */
303 #ifdef WITH_CONTENT_SCAN
306 FALSE, /* sender_domains */
309 #ifdef WITH_CONTENT_SCAN
312 #ifdef EXPERIMENTAL_SPF
318 /* Bit map vector of which conditions are not allowed at certain times. For
319 each condition, there's a bitmap of dis-allowed times. For some, it is easier
320 to specify the negation of a small number of allowed times. */
322 static unsigned int cond_forbids[] = {
326 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* add_header */
327 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
328 (1<<ACL_WHERE_MIME)|(1<<ACL_WHERE_NOTSMTP)),
330 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_CONNECT)| /* authenticated */
333 #ifdef EXPERIMENTAL_BRIGHTMAIL
334 (1<<ACL_WHERE_AUTH)| /* bmi_optin */
335 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
336 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_MIME)|
337 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
338 (1<<ACL_WHERE_MAILAUTH)|
339 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
340 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_PREDATA),
345 /* Certain types of control are always allowed, so we let it through
346 always and check in the control processing itself. */
350 #ifdef WITH_CONTENT_SCAN
352 ~(1<<ACL_WHERE_MIME), /* decode */
357 #ifdef WITH_OLD_DEMIME
359 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)), /* demime */
362 #ifdef EXPERIMENTAL_DOMAINKEYS
363 (1<<ACL_WHERE_AUTH)| /* dk_domain_source */
364 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
365 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
366 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
367 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
368 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
371 (1<<ACL_WHERE_AUTH)| /* dk_policy */
372 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
373 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
374 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
375 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
376 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
379 (1<<ACL_WHERE_AUTH)| /* dk_sender_domains */
380 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
381 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
382 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
383 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
384 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
387 (1<<ACL_WHERE_AUTH)| /* dk_sender_local_parts */
388 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
389 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
390 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
391 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
392 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
395 (1<<ACL_WHERE_AUTH)| /* dk_senders */
396 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
397 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
398 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
399 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
400 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
403 (1<<ACL_WHERE_AUTH)| /* dk_status */
404 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
405 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
406 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
407 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
408 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
412 (1<<ACL_WHERE_NOTSMTP), /* dnslists */
415 ~(1<<ACL_WHERE_RCPT), /* domains */
417 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_CONNECT)| /* encrypted */
422 (1<<ACL_WHERE_NOTSMTP), /* hosts */
425 ~(1<<ACL_WHERE_RCPT), /* local_parts */
431 #ifdef WITH_CONTENT_SCAN
433 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)), /* malware */
438 #ifdef WITH_CONTENT_SCAN
440 ~(1<<ACL_WHERE_MIME), /* mime_regex */
446 ~(1<<ACL_WHERE_RCPT), /* recipients */
448 #ifdef WITH_CONTENT_SCAN
450 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* regex */
451 (1<<ACL_WHERE_MIME)),
454 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* sender_domains */
456 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
457 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
458 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
460 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* senders */
462 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
463 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
464 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
468 #ifdef WITH_CONTENT_SCAN
470 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)), /* spam */
473 #ifdef EXPERIMENTAL_SPF
474 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* spf */
476 (1<<ACL_WHERE_MAILAUTH)|
477 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
478 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
481 /* Certain types of verify are always allowed, so we let it through
482 always and check in the verify function itself */
488 /* Bit map vector of which controls are not allowed at certain times. For
489 each control, there's a bitmap of dis-allowed times. For some, it is easier to
490 specify the negation of a small number of allowed times. */
492 static unsigned int control_forbids[] = {
494 ~((1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)), /* allow_auth_unadvertised */
496 #ifdef EXPERIMENTAL_BRIGHTMAIL
500 #ifdef EXPERIMENTAL_DOMAINKEYS
501 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), /* dk_verify */
507 ~(1<<ACL_WHERE_RCPT), /* caseful_local_part */
510 ~(1<<ACL_WHERE_RCPT), /* caselower_local_part */
512 (1<<ACL_WHERE_NOTSMTP), /* enforce_sync */
514 (1<<ACL_WHERE_NOTSMTP), /* no_enforce_sync */
517 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* freeze */
518 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
519 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)),
522 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* queue_only */
523 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
524 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)),
527 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* submission */
528 (1<<ACL_WHERE_PREDATA)),
531 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* suppress_local_fixups */
532 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_PREDATA)),
534 #ifdef WITH_CONTENT_SCAN
536 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* no_mbox_unspool */
537 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
538 (1<<ACL_WHERE_MIME)),
542 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakedefer */
543 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
544 (1<<ACL_WHERE_MIME)),
547 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakereject */
548 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
549 (1<<ACL_WHERE_MIME)),
551 (1<<ACL_WHERE_NOTSMTP) /* no_multiline */
554 /* Structure listing various control arguments, with their characteristics. */
556 typedef struct control_def {
558 int value; /* CONTROL_xxx value */
559 BOOL has_option; /* Has /option(s) following */
562 static control_def controls_list[] = {
563 { US"allow_auth_unadvertised", CONTROL_AUTH_UNADVERTISED, FALSE },
564 #ifdef EXPERIMENTAL_BRIGHTMAIL
565 { US"bmi_run", CONTROL_BMI_RUN, FALSE },
567 #ifdef EXPERIMENTAL_DOMAINKEYS
568 { US"dk_verify", CONTROL_DK_VERIFY, FALSE },
570 { US"caseful_local_part", CONTROL_CASEFUL_LOCAL_PART, FALSE },
571 { US"caselower_local_part", CONTROL_CASELOWER_LOCAL_PART, FALSE },
572 { US"enforce_sync", CONTROL_ENFORCE_SYNC, FALSE },
573 { US"freeze", CONTROL_FREEZE, TRUE },
574 { US"no_enforce_sync", CONTROL_NO_ENFORCE_SYNC, FALSE },
575 { US"no_multiline_responses", CONTROL_NO_MULTILINE, FALSE },
576 { US"queue_only", CONTROL_QUEUE_ONLY, FALSE },
577 #ifdef WITH_CONTENT_SCAN
578 { US"no_mbox_unspool", CONTROL_NO_MBOX_UNSPOOL, FALSE },
580 { US"fakedefer", CONTROL_FAKEDEFER, TRUE },
581 { US"fakereject", CONTROL_FAKEREJECT, TRUE },
582 { US"submission", CONTROL_SUBMISSION, TRUE },
583 { US"suppress_local_fixups", CONTROL_SUPPRESS_LOCAL_FIXUPS, FALSE }
586 /* Support data structures for Client SMTP Authorization. acl_verify_csa()
587 caches its result in a tree to avoid repeated DNS queries. The result is an
588 integer code which is used as an index into the following tables of
589 explanatory strings and verification return codes. */
591 static tree_node *csa_cache = NULL;
593 enum { CSA_UNKNOWN, CSA_OK, CSA_DEFER_SRV, CSA_DEFER_ADDR,
594 CSA_FAIL_EXPLICIT, CSA_FAIL_DOMAIN, CSA_FAIL_NOADDR, CSA_FAIL_MISMATCH };
596 /* The acl_verify_csa() return code is translated into an acl_verify() return
597 code using the following table. It is OK unless the client is definitely not
598 authorized. This is because CSA is supposed to be optional for sending sites,
599 so recipients should not be too strict about checking it - especially because
600 DNS problems are quite likely to occur. It's possible to use $csa_status in
601 further ACL conditions to distinguish ok, unknown, and defer if required, but
602 the aim is to make the usual configuration simple. */
604 static int csa_return_code[] = {
606 FAIL, FAIL, FAIL, FAIL
609 static uschar *csa_status_string[] = {
610 US"unknown", US"ok", US"defer", US"defer",
611 US"fail", US"fail", US"fail", US"fail"
614 static uschar *csa_reason_string[] = {
617 US"deferred (SRV lookup failed)",
618 US"deferred (target address lookup failed)",
619 US"failed (explicit authorization required)",
620 US"failed (host name not authorized)",
621 US"failed (no authorized addresses)",
622 US"failed (client address mismatch)"
625 /* Enable recursion between acl_check_internal() and acl_check_condition() */
627 static int acl_check_internal(int, address_item *, uschar *, int, uschar **,
631 /*************************************************
632 * Pick out name from list *
633 *************************************************/
635 /* Use a binary chop method
642 Returns: offset in list, or -1 if not found
646 acl_checkname(uschar *name, uschar **list, int end)
652 int mid = (start + end)/2;
653 int c = Ustrcmp(name, list[mid]);
654 if (c == 0) return mid;
655 if (c < 0) end = mid; else start = mid + 1;
662 /*************************************************
663 * Read and parse one ACL *
664 *************************************************/
666 /* This function is called both from readconf in order to parse the ACLs in the
667 configuration file, and also when an ACL is encountered dynamically (e.g. as
668 the result of an expansion). It is given a function to call in order to
669 retrieve the lines of the ACL. This function handles skipping comments and
670 blank lines (where relevant).
673 func function to get next line of ACL
674 error where to put an error message
676 Returns: pointer to ACL, or NULL
677 NULL can be legal (empty ACL); in this case error will be NULL
681 acl_read(uschar *(*func)(void), uschar **error)
683 acl_block *yield = NULL;
684 acl_block **lastp = &yield;
685 acl_block *this = NULL;
686 acl_condition_block *cond;
687 acl_condition_block **condp = NULL;
692 while ((s = (*func)()) != NULL)
695 BOOL negated = FALSE;
696 uschar *saveline = s;
699 /* Conditions (but not verbs) are allowed to be negated by an initial
702 while (isspace(*s)) s++;
709 /* Read the name of a verb or a condition, or the start of a new ACL, which
710 can be started by a name, or by a macro definition. */
712 s = readconf_readname(name, sizeof(name), s);
713 if (*s == ':' || isupper(name[0] && *s == '=')) return yield;
715 /* If a verb is unrecognized, it may be another condition or modifier that
716 continues the previous verb. */
718 v = acl_checkname(name, verbs, sizeof(verbs)/sizeof(char *));
723 *error = string_sprintf("unknown ACL verb in \"%s\"", saveline);
734 *error = string_sprintf("malformed ACL line \"%s\"", saveline);
737 this = store_get(sizeof(acl_block));
739 lastp = &(this->next);
742 this->condition = NULL;
743 condp = &(this->condition);
744 if (*s == 0) continue; /* No condition on this line */
750 s = readconf_readname(name, sizeof(name), s); /* Condition name */
753 /* Handle a condition or modifier. */
755 c = acl_checkname(name, conditions, sizeof(conditions)/sizeof(char *));
758 *error = string_sprintf("unknown ACL condition/modifier in \"%s\"",
763 /* The modifiers may not be negated */
765 if (negated && cond_modifiers[c])
767 *error = string_sprintf("ACL error: negation is not allowed with "
768 "\"%s\"", conditions[c]);
772 /* ENDPASS may occur only with ACCEPT or DISCARD. */
774 if (c == ACLC_ENDPASS &&
775 this->verb != ACL_ACCEPT &&
776 this->verb != ACL_DISCARD)
778 *error = string_sprintf("ACL error: \"%s\" is not allowed with \"%s\"",
779 conditions[c], verbs[this->verb]);
783 cond = store_get(sizeof(acl_condition_block));
786 cond->u.negated = negated;
789 condp = &(cond->next);
791 /* The "set" modifier is different in that its argument is "name=value"
792 rather than just a value, and we can check the validity of the name, which
793 gives us a variable number to insert into the data block. */
800 if (Ustrncmp(s, "acl_", 4) != 0) goto BAD_ACL_VAR;
806 else if (s[4] == 'm')
811 else goto BAD_ACL_VAR;
813 n = Ustrtoul(s + 5, &endptr, 10);
814 if ((*endptr != 0 && *endptr != '=' && !isspace(*endptr)) || n >= max)
817 *error = string_sprintf("syntax error or unrecognized name after "
818 "\"set\" in ACL modifier \"set %s\"", s);
822 cond->u.varnumber = n + offset;
824 while (isspace(*s)) s++;
827 /* For "set", we are now positioned for the data. For the others, only
828 "endpass" has no data */
830 if (c != ACLC_ENDPASS)
834 *error = string_sprintf("\"=\" missing after ACL \"%s\" %s", name,
835 cond_modifiers[c]? US"modifier" : US"condition");
838 while (isspace(*s)) s++;
839 cond->arg = string_copy(s);
848 /*************************************************
849 * Set up added header line(s) *
850 *************************************************/
852 /* This function is called by the add_header modifier, and also from acl_warn()
853 to implement the now-deprecated way of adding header lines using "message" on a
854 "warn" verb. The argument is treated as a sequence of header lines which are
855 added to a chain, provided there isn't an identical one already there.
857 Argument: string of header lines
862 setup_header(uschar *hstring)
865 int hlen = Ustrlen(hstring);
867 /* An empty string does nothing; otherwise add a final newline if necessary. */
869 if (hlen <= 0) return;
870 if (hstring[hlen-1] != '\n') hstring = string_sprintf("%s\n", hstring);
872 /* Loop for multiple header lines, taking care about continuations */
874 for (p = q = hstring; *p != 0; )
877 int newtype = htype_add_bot;
878 header_line **hptr = &acl_added_headers;
880 /* Find next header line within the string */
884 q = Ustrchr(q, '\n');
885 if (*(++q) != ' ' && *q != '\t') break;
888 /* If the line starts with a colon, interpret the instruction for where to
889 add it. This temporarily sets up a new type. */
893 if (strncmpic(p, US":after_received:", 16) == 0)
895 newtype = htype_add_rec;
898 else if (strncmpic(p, US":at_start_rfc:", 14) == 0)
900 newtype = htype_add_rfc;
903 else if (strncmpic(p, US":at_start:", 10) == 0)
905 newtype = htype_add_top;
908 else if (strncmpic(p, US":at_end:", 8) == 0)
910 newtype = htype_add_bot;
913 while (*p == ' ' || *p == '\t') p++;
916 /* See if this line starts with a header name, and if not, add X-ACL-Warn:
917 to the front of it. */
919 for (s = p; s < q - 1; s++)
921 if (*s == ':' || !isgraph(*s)) break;
924 s = string_sprintf("%s%.*s", (*s == ':')? "" : "X-ACL-Warn: ", q - p, p);
927 /* See if this line has already been added */
929 while (*hptr != NULL)
931 if (Ustrncmp((*hptr)->text, s, hlen) == 0) break;
932 hptr = &((*hptr)->next);
935 /* Add if not previously present */
939 header_line *h = store_get(sizeof(header_line));
948 /* Advance for next header line within the string */
957 /*************************************************
959 *************************************************/
961 /* This function is called when a WARN verb's conditions are true. It adds to
962 the message's headers, and/or writes information to the log. In each case, this
963 only happens once (per message for headers, per connection for log).
965 ** NOTE: The header adding action using the "message" setting is historic, and
966 its use is now deprecated. The new add_header modifier should be used instead.
969 where ACL_WHERE_xxxx indicating which ACL this is
970 user_message message for adding to headers
971 log_message message for logging, if different
977 acl_warn(int where, uschar *user_message, uschar *log_message)
979 if (log_message != NULL && log_message != user_message)
984 text = string_sprintf("%s Warning: %s", host_and_ident(TRUE),
985 string_printing(log_message));
987 /* If a sender verification has failed, and the log message is "sender verify
988 failed", add the failure message. */
990 if (sender_verified_failed != NULL &&
991 sender_verified_failed->message != NULL &&
992 strcmpic(log_message, US"sender verify failed") == 0)
993 text = string_sprintf("%s: %s", text, sender_verified_failed->message);
995 /* Search previously logged warnings. They are kept in malloc
996 store so they can be freed at the start of a new message. */
998 for (logged = acl_warn_logged; logged != NULL; logged = logged->next)
999 if (Ustrcmp(logged->text, text) == 0) break;
1003 int length = Ustrlen(text) + 1;
1004 log_write(0, LOG_MAIN, "%s", text);
1005 logged = store_malloc(sizeof(string_item) + length);
1006 logged->text = (uschar *)logged + sizeof(string_item);
1007 memcpy(logged->text, text, length);
1008 logged->next = acl_warn_logged;
1009 acl_warn_logged = logged;
1013 /* If there's no user message, we are done. */
1015 if (user_message == NULL) return;
1017 /* If this isn't a message ACL, we can't do anything with a user message.
1020 if (where > ACL_WHERE_NOTSMTP)
1022 log_write(0, LOG_MAIN|LOG_PANIC, "ACL \"warn\" with \"message\" setting "
1023 "found in a non-message (%s) ACL: cannot specify header lines here: "
1024 "message ignored", acl_wherenames[where]);
1028 /* The code for setting up header lines is now abstracted into a separate
1029 function so that it can be used for the add_header modifier as well. */
1031 setup_header(user_message);
1036 /*************************************************
1037 * Verify and check reverse DNS *
1038 *************************************************/
1040 /* Called from acl_verify() below. We look up the host name(s) of the client IP
1041 address if this has not yet been done. The host_name_lookup() function checks
1042 that one of these names resolves to an address list that contains the client IP
1043 address, so we don't actually have to do the check here.
1046 user_msgptr pointer for user message
1047 log_msgptr pointer for log message
1049 Returns: OK verification condition succeeded
1050 FAIL verification failed
1051 DEFER there was a problem verifying
1055 acl_verify_reverse(uschar **user_msgptr, uschar **log_msgptr)
1059 user_msgptr = user_msgptr; /* stop compiler warning */
1061 /* Previous success */
1063 if (sender_host_name != NULL) return OK;
1065 /* Previous failure */
1067 if (host_lookup_failed)
1069 *log_msgptr = string_sprintf("host lookup failed%s", host_lookup_msg);
1073 /* Need to do a lookup */
1076 debug_printf("looking up host name to force name/address consistency check\n");
1078 if ((rc = host_name_lookup()) != OK)
1080 *log_msgptr = (rc == DEFER)?
1081 US"host lookup deferred for reverse lookup check"
1083 string_sprintf("host lookup failed for reverse lookup check%s",
1085 return rc; /* DEFER or FAIL */
1088 host_build_sender_fullhost();
1094 /*************************************************
1095 * Check client IP address matches CSA target *
1096 *************************************************/
1098 /* Called from acl_verify_csa() below. This routine scans a section of a DNS
1099 response for address records belonging to the CSA target hostname. The section
1100 is specified by the reset argument, either RESET_ADDITIONAL or RESET_ANSWERS.
1101 If one of the addresses matches the client's IP address, then the client is
1102 authorized by CSA. If there are target IP addresses but none of them match
1103 then the client is using an unauthorized IP address. If there are no target IP
1104 addresses then the client cannot be using an authorized IP address. (This is
1105 an odd configuration - why didn't the SRV record have a weight of 1 instead?)
1108 dnsa the DNS answer block
1109 dnss a DNS scan block for us to use
1110 reset option specifing what portion to scan, as described above
1111 target the target hostname to use for matching RR names
1113 Returns: CSA_OK successfully authorized
1114 CSA_FAIL_MISMATCH addresses found but none matched
1115 CSA_FAIL_NOADDR no target addresses found
1119 acl_verify_csa_address(dns_answer *dnsa, dns_scan *dnss, int reset,
1125 BOOL target_found = FALSE;
1127 for (rr = dns_next_rr(dnsa, dnss, reset);
1129 rr = dns_next_rr(dnsa, dnss, RESET_NEXT))
1131 /* Check this is an address RR for the target hostname. */
1135 && rr->type != T_AAAA
1142 if (strcmpic(target, rr->name) != 0) continue;
1144 target_found = TRUE;
1146 /* Turn the target address RR into a list of textual IP addresses and scan
1147 the list. There may be more than one if it is an A6 RR. */
1149 for (da = dns_address_from_rr(dnsa, rr); da != NULL; da = da->next)
1151 /* If the client IP address matches the target IP address, it's good! */
1153 DEBUG(D_acl) debug_printf("CSA target address is %s\n", da->address);
1155 if (strcmpic(sender_host_address, da->address) == 0) return CSA_OK;
1159 /* If we found some target addresses but none of them matched, the client is
1160 using an unauthorized IP address, otherwise the target has no authorized IP
1163 if (target_found) return CSA_FAIL_MISMATCH;
1164 else return CSA_FAIL_NOADDR;
1169 /*************************************************
1170 * Verify Client SMTP Authorization *
1171 *************************************************/
1173 /* Called from acl_verify() below. This routine calls dns_lookup_special()
1174 to find the CSA SRV record corresponding to the domain argument, or
1175 $sender_helo_name if no argument is provided. It then checks that the
1176 client is authorized, and that its IP address corresponds to the SRV
1177 target's address by calling acl_verify_csa_address() above. The address
1178 should have been returned in the DNS response's ADDITIONAL section, but if
1179 not we perform another DNS lookup to get it.
1182 domain pointer to optional parameter following verify = csa
1184 Returns: CSA_UNKNOWN no valid CSA record found
1185 CSA_OK successfully authorized
1186 CSA_FAIL_* client is definitely not authorized
1187 CSA_DEFER_* there was a DNS problem
1191 acl_verify_csa(uschar *domain)
1195 int priority, weight, port;
1202 /* Work out the domain we are using for the CSA lookup. The default is the
1203 client's HELO domain. If the client has not said HELO, use its IP address
1204 instead. If it's a local client (exim -bs), CSA isn't applicable. */
1206 while (isspace(*domain) && *domain != '\0') ++domain;
1207 if (*domain == '\0') domain = sender_helo_name;
1208 if (domain == NULL) domain = sender_host_address;
1209 if (sender_host_address == NULL) return CSA_UNKNOWN;
1211 /* If we have an address literal, strip off the framing ready for turning it
1212 into a domain. The framing consists of matched square brackets possibly
1213 containing a keyword and a colon before the actual IP address. */
1215 if (domain[0] == '[')
1217 uschar *start = Ustrchr(domain, ':');
1218 if (start == NULL) start = domain;
1219 domain = string_copyn(start + 1, Ustrlen(start) - 2);
1222 /* Turn domains that look like bare IP addresses into domains in the reverse
1223 DNS. This code also deals with address literals and $sender_host_address. It's
1224 not quite kosher to treat bare domains such as EHLO 192.0.2.57 the same as
1225 address literals, but it's probably the most friendly thing to do. This is an
1226 extension to CSA, so we allow it to be turned off for proper conformance. */
1228 if (string_is_ip_address(domain, NULL) != 0)
1230 if (!dns_csa_use_reverse) return CSA_UNKNOWN;
1231 dns_build_reverse(domain, target);
1235 /* Find out if we've already done the CSA check for this domain. If we have,
1236 return the same result again. Otherwise build a new cached result structure
1237 for this domain. The name is filled in now, and the value is filled in when
1238 we return from this function. */
1240 t = tree_search(csa_cache, domain);
1241 if (t != NULL) return t->data.val;
1243 t = store_get_perm(sizeof(tree_node) + Ustrlen(domain));
1244 Ustrcpy(t->name, domain);
1245 (void)tree_insertnode(&csa_cache, t);
1247 /* Now we are ready to do the actual DNS lookup(s). */
1250 switch (dns_special_lookup(&dnsa, domain, T_CSA, &found))
1252 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1255 return t->data.val = CSA_DEFER_SRV;
1257 /* If we found nothing, the client's authorization is unknown. */
1261 return t->data.val = CSA_UNKNOWN;
1263 /* We got something! Go on to look at the reply in more detail. */
1269 /* Scan the reply for well-formed CSA SRV records. */
1271 for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS);
1273 rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT))
1275 if (rr->type != T_SRV) continue;
1277 /* Extract the numerical SRV fields (p is incremented) */
1280 GETSHORT(priority, p);
1281 GETSHORT(weight, p);
1285 debug_printf("CSA priority=%d weight=%d port=%d\n", priority, weight, port);
1287 /* Check the CSA version number */
1289 if (priority != 1) continue;
1291 /* If the domain does not have a CSA SRV record of its own (i.e. the domain
1292 found by dns_special_lookup() is a parent of the one we asked for), we check
1293 the subdomain assertions in the port field. At the moment there's only one
1294 assertion: legitimate SMTP clients are all explicitly authorized with CSA
1295 SRV records of their own. */
1297 if (found != domain)
1300 return t->data.val = CSA_FAIL_EXPLICIT;
1302 return t->data.val = CSA_UNKNOWN;
1305 /* This CSA SRV record refers directly to our domain, so we check the value
1306 in the weight field to work out the domain's authorization. 0 and 1 are
1307 unauthorized; 3 means the client is authorized but we can't check the IP
1308 address in order to authenticate it, so we treat it as unknown; values
1309 greater than 3 are undefined. */
1311 if (weight < 2) return t->data.val = CSA_FAIL_DOMAIN;
1313 if (weight > 2) continue;
1315 /* Weight == 2, which means the domain is authorized. We must check that the
1316 client's IP address is listed as one of the SRV target addresses. Save the
1317 target hostname then break to scan the additional data for its addresses. */
1319 (void)dn_expand(dnsa.answer, dnsa.answer + dnsa.answerlen, p,
1320 (DN_EXPAND_ARG4_TYPE)target, sizeof(target));
1322 DEBUG(D_acl) debug_printf("CSA target is %s\n", target);
1327 /* If we didn't break the loop then no appropriate records were found. */
1329 if (rr == NULL) return t->data.val = CSA_UNKNOWN;
1331 /* Do not check addresses if the target is ".", in accordance with RFC 2782.
1332 A target of "." indicates there are no valid addresses, so the client cannot
1333 be authorized. (This is an odd configuration because weight=2 target=. is
1334 equivalent to weight=1, but we check for it in order to keep load off the
1335 root name servers.) Note that dn_expand() turns "." into "". */
1337 if (Ustrcmp(target, "") == 0) return t->data.val = CSA_FAIL_NOADDR;
1339 /* Scan the additional section of the CSA SRV reply for addresses belonging
1340 to the target. If the name server didn't return any additional data (e.g.
1341 because it does not fully support SRV records), we need to do another lookup
1342 to obtain the target addresses; otherwise we have a definitive result. */
1344 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ADDITIONAL, target);
1345 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1347 /* The DNS lookup type corresponds to the IP version used by the client. */
1350 if (Ustrchr(sender_host_address, ':') != NULL)
1353 #endif /* HAVE_IPV6 */
1357 #if HAVE_IPV6 && defined(SUPPORT_A6)
1361 switch (dns_lookup(&dnsa, target, type, NULL))
1363 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1366 return t->data.val = CSA_DEFER_ADDR;
1368 /* If the query succeeded, scan the addresses and return the result. */
1371 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ANSWERS, target);
1372 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1373 /* else fall through */
1375 /* If the target has no IP addresses, the client cannot have an authorized
1376 IP address. However, if the target site uses A6 records (not AAAA records)
1377 we have to do yet another lookup in order to check them. */
1382 #if HAVE_IPV6 && defined(SUPPORT_A6)
1383 if (type == T_AAAA) { type = T_A6; goto DNS_LOOKUP_AGAIN; }
1386 return t->data.val = CSA_FAIL_NOADDR;
1392 /*************************************************
1393 * Handle verification (address & other) *
1394 *************************************************/
1396 /* This function implements the "verify" condition. It is called when
1397 encountered in any ACL, because some tests are almost always permitted. Some
1398 just don't make sense, and always fail (for example, an attempt to test a host
1399 lookup for a non-TCP/IP message). Others are restricted to certain ACLs.
1402 where where called from
1403 addr the recipient address that the ACL is handling, or NULL
1404 arg the argument of "verify"
1405 user_msgptr pointer for user message
1406 log_msgptr pointer for log message
1407 basic_errno where to put verify errno
1409 Returns: OK verification condition succeeded
1410 FAIL verification failed
1411 DEFER there was a problem verifying
1416 acl_verify(int where, address_item *addr, uschar *arg,
1417 uschar **user_msgptr, uschar **log_msgptr, int *basic_errno)
1421 int callout_overall = -1;
1422 int callout_connect = -1;
1423 int verify_options = 0;
1425 BOOL verify_header_sender = FALSE;
1426 BOOL defer_ok = FALSE;
1427 BOOL callout_defer_ok = FALSE;
1428 BOOL no_details = FALSE;
1429 BOOL success_on_redirect = FALSE;
1430 address_item *sender_vaddr = NULL;
1431 uschar *verify_sender_address = NULL;
1432 uschar *pm_mailfrom = NULL;
1433 uschar *se_mailfrom = NULL;
1435 /* Some of the verify items have slash-separated options; some do not. Diagnose
1436 an error if options are given for items that don't expect them. This code has
1437 now got very message. Refactoring to use a table would be a good idea one day.
1440 uschar *slash = Ustrchr(arg, '/');
1442 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
1444 if (ss == NULL) goto BAD_VERIFY;
1446 /* Handle name/address consistency verification in a separate function. */
1448 if (strcmpic(ss, US"reverse_host_lookup") == 0)
1450 if (slash != NULL) goto NO_OPTIONS;
1451 if (sender_host_address == NULL) return OK;
1452 return acl_verify_reverse(user_msgptr, log_msgptr);
1455 /* TLS certificate verification is done at STARTTLS time; here we just
1456 test whether it was successful or not. (This is for optional verification; for
1457 mandatory verification, the connection doesn't last this long.) */
1459 if (strcmpic(ss, US"certificate") == 0)
1461 if (slash != NULL) goto NO_OPTIONS;
1462 if (tls_certificate_verified) return OK;
1463 *user_msgptr = US"no verified certificate";
1467 /* We can test the result of optional HELO verification that might have
1468 occurred earlier. If not, we can attempt the verification now. */
1470 if (strcmpic(ss, US"helo") == 0)
1472 if (slash != NULL) goto NO_OPTIONS;
1473 if (!helo_verified && !helo_verify_failed) smtp_verify_helo();
1474 return helo_verified? OK : FAIL;
1477 /* Do Client SMTP Authorization checks in a separate function, and turn the
1478 result code into user-friendly strings. */
1480 if (strcmpic(ss, US"csa") == 0)
1482 rc = acl_verify_csa(list);
1483 *log_msgptr = *user_msgptr = string_sprintf("client SMTP authorization %s",
1484 csa_reason_string[rc]);
1485 csa_status = csa_status_string[rc];
1486 DEBUG(D_acl) debug_printf("CSA result %s\n", csa_status);
1487 return csa_return_code[rc];
1490 /* Check that all relevant header lines have the correct syntax. If there is
1491 a syntax error, we return details of the error to the sender if configured to
1492 send out full details. (But a "message" setting on the ACL can override, as
1495 if (strcmpic(ss, US"header_syntax") == 0)
1497 if (slash != NULL) goto NO_OPTIONS;
1498 if (where != ACL_WHERE_DATA && where != ACL_WHERE_NOTSMTP) goto WRONG_ACL;
1499 rc = verify_check_headers(log_msgptr);
1500 if (rc != OK && smtp_return_error_details && *log_msgptr != NULL)
1501 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1505 /* Check that no recipient of this message is "blind", that is, every envelope
1506 recipient must be mentioned in either To: or Cc:. */
1508 if (strcmpic(ss, US"not_blind") == 0)
1510 if (slash != NULL) goto NO_OPTIONS;
1511 if (where != ACL_WHERE_DATA && where != ACL_WHERE_NOTSMTP) goto WRONG_ACL;
1512 rc = verify_check_notblind();
1515 *log_msgptr = string_sprintf("bcc recipient detected");
1516 if (smtp_return_error_details)
1517 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1522 /* The remaining verification tests check recipient and sender addresses,
1523 either from the envelope or from the header. There are a number of
1524 slash-separated options that are common to all of them. */
1527 /* Check that there is at least one verifiable sender address in the relevant
1528 header lines. This can be followed by callout and defer options, just like
1529 sender and recipient. */
1531 if (strcmpic(ss, US"header_sender") == 0)
1533 if (where != ACL_WHERE_DATA && where != ACL_WHERE_NOTSMTP) goto WRONG_ACL;
1534 verify_header_sender = TRUE;
1537 /* Otherwise, first item in verify argument must be "sender" or "recipient".
1538 In the case of a sender, this can optionally be followed by an address to use
1539 in place of the actual sender (rare special-case requirement). */
1541 else if (strncmpic(ss, US"sender", 6) == 0)
1544 if (where > ACL_WHERE_NOTSMTP)
1546 *log_msgptr = string_sprintf("cannot verify sender in ACL for %s "
1547 "(only possible for MAIL, RCPT, PREDATA, or DATA)",
1548 acl_wherenames[where]);
1552 verify_sender_address = sender_address;
1555 while (isspace(*s)) s++;
1556 if (*s++ != '=') goto BAD_VERIFY;
1557 while (isspace(*s)) s++;
1558 verify_sender_address = string_copy(s);
1563 if (strcmpic(ss, US"recipient") != 0) goto BAD_VERIFY;
1566 *log_msgptr = string_sprintf("cannot verify recipient in ACL for %s "
1567 "(only possible for RCPT)", acl_wherenames[where]);
1572 /* Remaining items are optional; they apply to sender and recipient
1573 verification, including "header sender" verification. */
1575 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size))
1578 if (strcmpic(ss, US"defer_ok") == 0) defer_ok = TRUE;
1579 else if (strcmpic(ss, US"no_details") == 0) no_details = TRUE;
1580 else if (strcmpic(ss, US"success_on_redirect") == 0) success_on_redirect = TRUE;
1582 /* These two old options are left for backwards compatibility */
1584 else if (strcmpic(ss, US"callout_defer_ok") == 0)
1586 callout_defer_ok = TRUE;
1587 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1590 else if (strcmpic(ss, US"check_postmaster") == 0)
1593 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1596 /* The callout option has a number of sub-options, comma separated */
1598 else if (strncmpic(ss, US"callout", 7) == 0)
1600 callout = CALLOUT_TIMEOUT_DEFAULT;
1604 while (isspace(*ss)) ss++;
1610 while (isspace(*ss)) ss++;
1612 /* This callout option handling code has become a mess as new options
1613 have been added in an ad hoc manner. It should be tidied up into some
1614 kind of table-driven thing. */
1616 while ((opt = string_nextinlist(&ss, &optsep, buffer, sizeof(buffer)))
1619 if (strcmpic(opt, US"defer_ok") == 0) callout_defer_ok = TRUE;
1620 else if (strcmpic(opt, US"no_cache") == 0)
1621 verify_options |= vopt_callout_no_cache;
1622 else if (strcmpic(opt, US"random") == 0)
1623 verify_options |= vopt_callout_random;
1624 else if (strcmpic(opt, US"use_sender") == 0)
1625 verify_options |= vopt_callout_recipsender;
1626 else if (strcmpic(opt, US"use_postmaster") == 0)
1627 verify_options |= vopt_callout_recippmaster;
1628 else if (strcmpic(opt, US"postmaster") == 0) pm_mailfrom = US"";
1629 else if (strcmpic(opt, US"fullpostmaster") == 0)
1632 verify_options |= vopt_callout_fullpm;
1635 else if (strncmpic(opt, US"mailfrom", 8) == 0)
1637 if (!verify_header_sender)
1639 *log_msgptr = string_sprintf("\"mailfrom\" is allowed as a "
1640 "callout option only for verify=header_sender (detected in ACL "
1641 "condition \"%s\")", arg);
1645 while (isspace(*opt)) opt++;
1648 *log_msgptr = string_sprintf("'=' expected after "
1649 "\"mailfrom\" in ACL condition \"%s\"", arg);
1652 while (isspace(*opt)) opt++;
1653 se_mailfrom = string_copy(opt);
1656 else if (strncmpic(opt, US"postmaster_mailfrom", 19) == 0)
1659 while (isspace(*opt)) opt++;
1662 *log_msgptr = string_sprintf("'=' expected after "
1663 "\"postmaster_mailfrom\" in ACL condition \"%s\"", arg);
1666 while (isspace(*opt)) opt++;
1667 pm_mailfrom = string_copy(opt);
1670 else if (strncmpic(opt, US"maxwait", 7) == 0)
1673 while (isspace(*opt)) opt++;
1676 *log_msgptr = string_sprintf("'=' expected after \"maxwait\" in "
1677 "ACL condition \"%s\"", arg);
1680 while (isspace(*opt)) opt++;
1681 callout_overall = readconf_readtime(opt, 0, FALSE);
1682 if (callout_overall < 0)
1684 *log_msgptr = string_sprintf("bad time value in ACL condition "
1685 "\"verify %s\"", arg);
1689 else if (strncmpic(opt, US"connect", 7) == 0)
1692 while (isspace(*opt)) opt++;
1695 *log_msgptr = string_sprintf("'=' expected after "
1696 "\"callout_overaall\" in ACL condition \"%s\"", arg);
1699 while (isspace(*opt)) opt++;
1700 callout_connect = readconf_readtime(opt, 0, FALSE);
1701 if (callout_connect < 0)
1703 *log_msgptr = string_sprintf("bad time value in ACL condition "
1704 "\"verify %s\"", arg);
1708 else /* Plain time is callout connect/command timeout */
1710 callout = readconf_readtime(opt, 0, FALSE);
1713 *log_msgptr = string_sprintf("bad time value in ACL condition "
1714 "\"verify %s\"", arg);
1722 *log_msgptr = string_sprintf("'=' expected after \"callout\" in "
1723 "ACL condition \"%s\"", arg);
1729 /* Option not recognized */
1733 *log_msgptr = string_sprintf("unknown option \"%s\" in ACL "
1734 "condition \"verify %s\"", ss, arg);
1739 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster)) ==
1740 (vopt_callout_recipsender|vopt_callout_recippmaster))
1742 *log_msgptr = US"only one of use_sender and use_postmaster can be set "
1743 "for a recipient callout";
1747 /* Handle sender-in-header verification. Default the user message to the log
1748 message if giving out verification details. */
1750 if (verify_header_sender)
1753 rc = verify_check_header_address(user_msgptr, log_msgptr, callout,
1754 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, verify_options,
1758 *basic_errno = verrno;
1759 if (smtp_return_error_details)
1761 if (*user_msgptr == NULL && *log_msgptr != NULL)
1762 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1763 if (rc == DEFER) acl_temp_details = TRUE;
1768 /* Handle a sender address. The default is to verify *the* sender address, but
1769 optionally a different address can be given, for special requirements. If the
1770 address is empty, we are dealing with a bounce message that has no sender, so
1771 we cannot do any checking. If the real sender address gets rewritten during
1772 verification (e.g. DNS widening), set the flag to stop it being rewritten again
1773 during message reception.
1775 A list of verified "sender" addresses is kept to try to avoid doing to much
1776 work repetitively when there are multiple recipients in a message and they all
1777 require sender verification. However, when callouts are involved, it gets too
1778 complicated because different recipients may require different callout options.
1779 Therefore, we always do a full sender verify when any kind of callout is
1780 specified. Caching elsewhere, for instance in the DNS resolver and in the
1781 callout handling, should ensure that this is not terribly inefficient. */
1783 else if (verify_sender_address != NULL)
1785 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster))
1788 *log_msgptr = US"use_sender or use_postmaster cannot be used for a "
1789 "sender verify callout";
1793 sender_vaddr = verify_checked_sender(verify_sender_address);
1794 if (sender_vaddr != NULL && /* Previously checked */
1795 callout <= 0) /* No callout needed this time */
1797 /* If the "routed" flag is set, it means that routing worked before, so
1798 this check can give OK (the saved return code value, if set, belongs to a
1799 callout that was done previously). If the "routed" flag is not set, routing
1800 must have failed, so we use the saved return code. */
1802 if (testflag(sender_vaddr, af_verify_routed)) rc = OK; else
1804 rc = sender_vaddr->special_action;
1805 *basic_errno = sender_vaddr->basic_errno;
1807 HDEBUG(D_acl) debug_printf("using cached sender verify result\n");
1810 /* Do a new verification, and cache the result. The cache is used to avoid
1811 verifying the sender multiple times for multiple RCPTs when callouts are not
1812 specified (see comments above).
1814 The cache is also used on failure to give details in response to the first
1815 RCPT that gets bounced for this reason. However, this can be suppressed by
1816 the no_details option, which sets the flag that says "this detail has already
1817 been sent". The cache normally contains just one address, but there may be
1818 more in esoteric circumstances. */
1823 uschar *save_address_data = deliver_address_data;
1825 sender_vaddr = deliver_make_addr(verify_sender_address, TRUE);
1826 if (no_details) setflag(sender_vaddr, af_sverify_told);
1827 if (verify_sender_address[0] != 0)
1829 /* If this is the real sender address, save the unrewritten version
1830 for use later in receive. Otherwise, set a flag so that rewriting the
1831 sender in verify_address() does not update sender_address. */
1833 if (verify_sender_address == sender_address)
1834 sender_address_unrewritten = sender_address;
1836 verify_options |= vopt_fake_sender;
1838 if (success_on_redirect)
1839 verify_options |= vopt_success_on_redirect;
1841 /* The recipient, qualify, and expn options are never set in
1844 rc = verify_address(sender_vaddr, NULL, verify_options, callout,
1845 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, &routed);
1847 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
1851 if (Ustrcmp(sender_vaddr->address, verify_sender_address) != 0)
1853 DEBUG(D_acl) debug_printf("sender %s verified ok as %s\n",
1854 verify_sender_address, sender_vaddr->address);
1858 DEBUG(D_acl) debug_printf("sender %s verified ok\n",
1859 verify_sender_address);
1862 else *basic_errno = sender_vaddr->basic_errno;
1864 else rc = OK; /* Null sender */
1866 /* Cache the result code */
1868 if (routed) setflag(sender_vaddr, af_verify_routed);
1869 if (callout > 0) setflag(sender_vaddr, af_verify_callout);
1870 sender_vaddr->special_action = rc;
1871 sender_vaddr->next = sender_verified_list;
1872 sender_verified_list = sender_vaddr;
1874 /* Restore the recipient address data, which might have been clobbered by
1875 the sender verification. */
1877 deliver_address_data = save_address_data;
1880 /* Put the sender address_data value into $sender_address_data */
1882 sender_address_data = sender_vaddr->p.address_data;
1885 /* A recipient address just gets a straightforward verify; again we must handle
1886 the DEFER overrides. */
1892 if (success_on_redirect)
1893 verify_options |= vopt_success_on_redirect;
1895 /* We must use a copy of the address for verification, because it might
1899 rc = verify_address(&addr2, NULL, verify_options|vopt_is_recipient, callout,
1900 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, NULL);
1901 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
1903 *log_msgptr = addr2.message;
1904 *user_msgptr = (addr2.user_message != NULL)?
1905 addr2.user_message : addr2.message;
1906 *basic_errno = addr2.basic_errno;
1908 /* Make $address_data visible */
1909 deliver_address_data = addr2.p.address_data;
1912 /* We have a result from the relevant test. Handle defer overrides first. */
1914 if (rc == DEFER && (defer_ok ||
1915 (callout_defer_ok && *basic_errno == ERRNO_CALLOUTDEFER)))
1917 HDEBUG(D_acl) debug_printf("verify defer overridden by %s\n",
1918 defer_ok? "defer_ok" : "callout_defer_ok");
1922 /* If we've failed a sender, set up a recipient message, and point
1923 sender_verified_failed to the address item that actually failed. */
1925 if (rc != OK && verify_sender_address != NULL)
1929 *log_msgptr = *user_msgptr = US"Sender verify failed";
1931 else if (*basic_errno != ERRNO_CALLOUTDEFER)
1933 *log_msgptr = *user_msgptr = US"Could not complete sender verify";
1937 *log_msgptr = US"Could not complete sender verify callout";
1938 *user_msgptr = smtp_return_error_details? sender_vaddr->user_message :
1942 sender_verified_failed = sender_vaddr;
1945 /* Verifying an address messes up the values of $domain and $local_part,
1946 so reset them before returning if this is a RCPT ACL. */
1950 deliver_domain = addr->domain;
1951 deliver_localpart = addr->local_part;
1955 /* Syntax errors in the verify argument come here. */
1958 *log_msgptr = string_sprintf("expected \"sender[=address]\", \"recipient\", "
1959 "\"helo\", \"header_syntax\", \"header_sender\" or "
1960 "\"reverse_host_lookup\" at start of ACL condition "
1961 "\"verify %s\"", arg);
1964 /* Options supplied when not allowed come here */
1967 *log_msgptr = string_sprintf("unexpected '/' found in \"%s\" "
1968 "(this verify item has no options)", arg);
1971 /* Calls in the wrong ACL come here */
1974 *log_msgptr = string_sprintf("cannot check header contents in ACL for %s "
1975 "(only possible in ACL for DATA)", acl_wherenames[where]);
1982 /*************************************************
1983 * Check argument for control= modifier *
1984 *************************************************/
1986 /* Called from acl_check_condition() below
1989 arg the argument string for control=
1990 pptr set to point to the terminating character
1991 where which ACL we are in
1992 log_msgptr for error messages
1994 Returns: CONTROL_xxx value
1998 decode_control(uschar *arg, uschar **pptr, int where, uschar **log_msgptr)
2003 for (d = controls_list;
2004 d < controls_list + sizeof(controls_list)/sizeof(control_def);
2007 len = Ustrlen(d->name);
2008 if (Ustrncmp(d->name, arg, len) == 0) break;
2011 if (d >= controls_list + sizeof(controls_list)/sizeof(control_def) ||
2012 (arg[len] != 0 && (!d->has_option || arg[len] != '/')))
2014 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
2015 return CONTROL_ERROR;
2024 /*************************************************
2025 * Handle rate limiting *
2026 *************************************************/
2028 /* Called by acl_check_condition() below to calculate the result
2029 of the ACL ratelimit condition.
2031 Note that the return value might be slightly unexpected: if the
2032 sender's rate is above the limit then the result is OK. This is
2033 similar to the dnslists condition, and is so that you can write
2034 ACL clauses like: defer ratelimit = 15 / 1h
2037 arg the option string for ratelimit=
2038 where ACL_WHERE_xxxx indicating which ACL this is
2039 log_msgptr for error messages
2041 Returns: OK - Sender's rate is above limit
2042 FAIL - Sender's rate is below limit
2043 DEFER - Problem opening ratelimit database
2044 ERROR - Syntax error in options.
2048 acl_ratelimit(uschar *arg, int where, uschar **log_msgptr)
2050 double limit, period;
2053 BOOL have_key = FALSE, leaky = FALSE, strict = FALSE;
2054 BOOL per_byte = FALSE, per_cmd = FALSE, per_conn = FALSE, per_mail = FALSE;
2056 tree_node **anchor, *t;
2057 open_db dbblock, *dbm;
2058 dbdata_ratelimit *dbd;
2061 /* Parse the first two options and record their values in expansion
2062 variables. These variables allow the configuration to have informative
2063 error messages based on rate limits obtained from a table lookup. */
2065 /* First is the maximum number of messages per period and maximum burst
2066 size, which must be greater than or equal to zero. Zero is useful for
2067 rate measurement as opposed to rate limiting. */
2069 sender_rate_limit = string_nextinlist(&arg, &sep, NULL, 0);
2070 if (sender_rate_limit == NULL)
2074 limit = Ustrtod(sender_rate_limit, &ss);
2075 if (tolower(*ss) == 'k') { limit *= 1024.0; ss++; }
2076 else if (tolower(*ss) == 'm') { limit *= 1024.0*1024.0; ss++; }
2077 else if (tolower(*ss) == 'g') { limit *= 1024.0*1024.0*1024.0; ss++; }
2079 if (limit < 0.0 || *ss != 0)
2081 *log_msgptr = string_sprintf("syntax error in argument for "
2082 "\"ratelimit\" condition: \"%s\" is not a positive number",
2087 /* We use the rest of the argument list following the limit as the
2088 lookup key, because it doesn't make sense to use the same stored data
2089 if the period or options are different. */
2093 /* Second is the rate measurement period and exponential smoothing time
2094 constant. This must be strictly greater than zero, because zero leads to
2095 run-time division errors. */
2097 sender_rate_period = string_nextinlist(&arg, &sep, NULL, 0);
2098 if (sender_rate_period == NULL) period = -1.0;
2099 else period = readconf_readtime(sender_rate_period, 0, FALSE);
2102 *log_msgptr = string_sprintf("syntax error in argument for "
2103 "\"ratelimit\" condition: \"%s\" is not a time value",
2104 sender_rate_period);
2108 /* Parse the other options. Should we check if the per_* options are being
2109 used in ACLs where they don't make sense, e.g. per_mail in the connect ACL? */
2111 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2114 if (strcmpic(ss, US"leaky") == 0) leaky = TRUE;
2115 else if (strcmpic(ss, US"strict") == 0) strict = TRUE;
2116 else if (strcmpic(ss, US"per_byte") == 0) per_byte = TRUE;
2117 else if (strcmpic(ss, US"per_cmd") == 0) per_cmd = TRUE;
2118 else if (strcmpic(ss, US"per_conn") == 0) per_conn = TRUE;
2119 else if (strcmpic(ss, US"per_mail") == 0) per_mail = TRUE;
2120 else if (strcmpic(ss, US"per_rcpt") == 0) per_cmd = TRUE; /* alias */
2121 else have_key = TRUE;
2123 if (leaky + strict > 1 || per_byte + per_cmd + per_conn + per_mail > 1)
2125 *log_msgptr = US"conflicting options for \"ratelimit\" condition";
2129 /* Default option values */
2130 if (!strict) leaky = TRUE;
2131 if (!per_byte && !per_cmd && !per_conn) per_mail = TRUE;
2133 /* If there is no explicit key, use the sender_host_address. If there is no
2134 sender_host_address (e.g. -bs or acl_not_smtp) then we simply omit it. */
2136 if (!have_key && sender_host_address != NULL)
2137 key = string_sprintf("%s / %s", key, sender_host_address);
2139 HDEBUG(D_acl) debug_printf("ratelimit condition limit=%.0f period=%.0f key=%s\n",
2140 limit, period, key);
2142 /* See if we have already computed the rate by looking in the relevant tree. For
2143 per-connection rate limiting, store tree nodes and dbdata in the permanent pool
2144 so that they survive across resets. */
2147 old_pool = store_pool;
2151 anchor = &ratelimiters_conn;
2152 store_pool = POOL_PERM;
2154 else if (per_mail || per_byte)
2155 anchor = &ratelimiters_mail;
2157 anchor = &ratelimiters_cmd;
2159 if (anchor != NULL && (t = tree_search(*anchor, key)) != NULL)
2162 /* The following few lines duplicate some of the code below. */
2163 if (dbd->rate < limit) rc = FAIL;
2165 store_pool = old_pool;
2166 sender_rate = string_sprintf("%.1f", dbd->rate);
2168 debug_printf("ratelimit found pre-computed rate %s\n", sender_rate);
2172 /* We aren't using a pre-computed rate, so get a previously recorded
2173 rate from the database, update it, and write it back. If there's no
2174 previous rate for this key, create one. */
2176 dbm = dbfn_open(US"ratelimit", O_RDWR, &dbblock, TRUE);
2179 store_pool = old_pool;
2181 HDEBUG(D_acl) debug_printf("ratelimit database not available\n");
2182 *log_msgptr = US"ratelimit database not available";
2185 dbd = dbfn_read(dbm, key);
2187 gettimeofday(&tv, NULL);
2191 HDEBUG(D_acl) debug_printf("ratelimit initializing new key's data\n");
2192 dbd = store_get(sizeof(dbdata_ratelimit));
2193 dbd->time_stamp = tv.tv_sec;
2194 dbd->time_usec = tv.tv_usec;
2199 /* The smoothed rate is computed using an exponentially weighted moving
2200 average adjusted for variable sampling intervals. The standard EWMA for
2201 a fixed sampling interval is: f'(t) = (1 - a) * f(t) + a * f'(t - 1)
2202 where f() is the measured value and f'() is the smoothed value.
2204 Old data decays out of the smoothed value exponentially, such that data n
2205 samples old is multiplied by a^n. The exponential decay time constant p
2206 is defined such that data p samples old is multiplied by 1/e, which means
2207 that a = exp(-1/p). We can maintain the same time constant for a variable
2208 sampling interval i by using a = exp(-i/p).
2210 The rate we are measuring is messages per period, suitable for directly
2211 comparing with the limit. The average rate between now and the previous
2212 message is period / interval, which we feed into the EWMA as the sample.
2214 It turns out that the number of messages required for the smoothed rate
2215 to reach the limit when they are sent in a burst is equal to the limit.
2216 This can be seen by analysing the value of the smoothed rate after N
2217 messages sent at even intervals. Let k = (1 - a) * p/i
2219 rate_1 = (1 - a) * p/i + a * rate_0
2221 rate_2 = k + a * rate_1
2222 = k + a * k + a^2 * rate_0
2223 rate_3 = k + a * k + a^2 * k + a^3 * rate_0
2224 rate_N = rate_0 * a^N + k * SUM(x=0..N-1)(a^x)
2225 = rate_0 * a^N + k * (1 - a^N) / (1 - a)
2226 = rate_0 * a^N + p/i * (1 - a^N)
2228 When N is large, a^N -> 0 so rate_N -> p/i as desired.
2230 rate_N = p/i + (rate_0 - p/i) * a^N
2231 a^N = (rate_N - p/i) / (rate_0 - p/i)
2232 N * -i/p = log((rate_N - p/i) / (rate_0 - p/i))
2233 N = p/i * log((rate_0 - p/i) / (rate_N - p/i))
2235 Numerical analysis of the above equation, setting the computed rate to
2236 increase from rate_0 = 0 to rate_N = limit, shows that for large sending
2237 rates, p/i, the number of messages N = limit. So limit serves as both the
2238 maximum rate measured in messages per period, and the maximum number of
2239 messages that can be sent in a fast burst. */
2241 double this_time = (double)tv.tv_sec
2242 + (double)tv.tv_usec / 1000000.0;
2243 double prev_time = (double)dbd->time_stamp
2244 + (double)dbd->time_usec / 1000000.0;
2246 /* We must avoid division by zero, and deal gracefully with the clock going
2247 backwards. If we blunder ahead when time is in reverse then the computed
2248 rate will be bogus. To be safe we clamp interval to a very small number. */
2250 double interval = this_time - prev_time <= 0.0 ? 1e-9
2251 : this_time - prev_time;
2253 double i_over_p = interval / period;
2254 double a = exp(-i_over_p);
2256 dbd->time_stamp = tv.tv_sec;
2257 dbd->time_usec = tv.tv_usec;
2259 /* If we are measuring the rate in bytes per period, multiply the
2260 measured rate by the message size. If we don't know the message size
2261 then it's safe to just use a value of zero and let the recorded rate
2262 decay as if nothing happened. */
2265 dbd->rate = (message_size < 0 ? 0.0 : (double)message_size)
2266 * (1 - a) / i_over_p + a * dbd->rate;
2267 else if (per_cmd && where == ACL_WHERE_NOTSMTP)
2268 dbd->rate = (double)recipients_count
2269 * (1 - a) / i_over_p + a * dbd->rate;
2271 dbd->rate = (1 - a) / i_over_p + a * dbd->rate;
2274 /* Clients sending at the limit are considered to be over the limit. This
2275 matters for edge cases such the first message sent by a client (which gets
2276 the initial rate of 0.0) when the rate limit is zero (i.e. the client should
2277 be completely blocked). */
2279 if (dbd->rate < limit) rc = FAIL;
2282 /* Update the state if the rate is low or if we are being strict. If we
2283 are in leaky mode and the sender's rate is too high, we do not update
2284 the recorded rate in order to avoid an over-aggressive sender's retry
2285 rate preventing them from getting any email through. */
2287 if (rc == FAIL || !leaky)
2288 dbfn_write(dbm, key, dbd, sizeof(dbdata_ratelimit));
2291 /* Store the result in the tree for future reference, if necessary. */
2295 t = store_get(sizeof(tree_node) + Ustrlen(key));
2297 Ustrcpy(t->name, key);
2298 (void)tree_insertnode(anchor, t);
2301 /* We create the formatted version of the sender's rate very late in
2302 order to ensure that it is done using the correct storage pool. */
2304 store_pool = old_pool;
2305 sender_rate = string_sprintf("%.1f", dbd->rate);
2308 debug_printf("ratelimit computed rate %s\n", sender_rate);
2315 /*************************************************
2316 * Handle conditions/modifiers on an ACL item *
2317 *************************************************/
2319 /* Called from acl_check() below.
2323 cb ACL condition block - if NULL, result is OK
2324 where where called from
2325 addr the address being checked for RCPT, or NULL
2326 level the nesting level
2327 epp pointer to pass back TRUE if "endpass" encountered
2328 (applies only to "accept" and "discard")
2329 user_msgptr user message pointer
2330 log_msgptr log message pointer
2331 basic_errno pointer to where to put verify error
2333 Returns: OK - all conditions are met
2334 DISCARD - an "acl" condition returned DISCARD - only allowed
2335 for "accept" or "discard" verbs
2336 FAIL - at least one condition fails
2337 FAIL_DROP - an "acl" condition returned FAIL_DROP
2338 DEFER - can't tell at the moment (typically, lookup defer,
2339 but can be temporary callout problem)
2340 ERROR - ERROR from nested ACL or expansion failure or other
2345 acl_check_condition(int verb, acl_condition_block *cb, int where,
2346 address_item *addr, int level, BOOL *epp, uschar **user_msgptr,
2347 uschar **log_msgptr, int *basic_errno)
2349 uschar *user_message = NULL;
2350 uschar *log_message = NULL;
2353 #ifdef WITH_CONTENT_SCAN
2357 for (; cb != NULL; cb = cb->next)
2362 /* The message and log_message items set up messages to be used in
2363 case of rejection. They are expanded later. */
2365 if (cb->type == ACLC_MESSAGE)
2367 user_message = cb->arg;
2371 if (cb->type == ACLC_LOG_MESSAGE)
2373 log_message = cb->arg;
2377 /* The endpass "condition" just sets a flag to show it occurred. This is
2378 checked at compile time to be on an "accept" or "discard" item. */
2380 if (cb->type == ACLC_ENDPASS)
2386 /* For other conditions and modifiers, the argument is expanded now for some
2387 of them, but not for all, because expansion happens down in some lower level
2388 checking functions in some cases. */
2390 if (cond_expand_at_top[cb->type])
2392 arg = expand_string(cb->arg);
2395 if (expand_string_forcedfail) continue;
2396 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s",
2397 cb->arg, expand_string_message);
2398 return search_find_defer? DEFER : ERROR;
2403 /* Show condition, and expanded condition if it's different */
2408 debug_printf("check %s%s %n",
2409 (!cond_modifiers[cb->type] && cb->u.negated)? "!":"",
2410 conditions[cb->type], &lhswidth);
2412 if (cb->type == ACLC_SET)
2414 int n = cb->u.varnumber;
2415 int t = (n < ACL_CVARS)? 'c' : 'm';
2416 if (n >= ACL_CVARS) n -= ACL_CVARS;
2417 debug_printf("acl_%c%d ", t, n);
2421 debug_printf("= %s\n", cb->arg);
2424 debug_printf("%.*s= %s\n", lhswidth,
2428 /* Check that this condition makes sense at this time */
2430 if ((cond_forbids[cb->type] & (1 << where)) != 0)
2432 *log_msgptr = string_sprintf("cannot %s %s condition in %s ACL",
2433 cond_modifiers[cb->type]? "use" : "test",
2434 conditions[cb->type], acl_wherenames[where]);
2438 /* Run the appropriate test for each condition, or take the appropriate
2439 action for the remaining modifiers. */
2443 case ACLC_ADD_HEADER:
2447 /* A nested ACL that returns "discard" makes sense only for an "accept" or
2451 rc = acl_check_internal(where, addr, arg, level+1, user_msgptr, log_msgptr);
2452 if (rc == DISCARD && verb != ACL_ACCEPT && verb != ACL_DISCARD)
2454 *log_msgptr = string_sprintf("nested ACL returned \"discard\" for "
2455 "\"%s\" command (only allowed with \"accept\" or \"discard\")",
2461 case ACLC_AUTHENTICATED:
2462 rc = (sender_host_authenticated == NULL)? FAIL :
2463 match_isinlist(sender_host_authenticated, &arg, 0, NULL, NULL, MCL_STRING,
2467 #ifdef EXPERIMENTAL_BRIGHTMAIL
2468 case ACLC_BMI_OPTIN:
2470 int old_pool = store_pool;
2471 store_pool = POOL_PERM;
2472 bmi_current_optin = string_copy(arg);
2473 store_pool = old_pool;
2478 case ACLC_CONDITION:
2479 if (Ustrspn(arg, "0123456789") == Ustrlen(arg)) /* Digits, or empty */
2480 rc = (Uatoi(arg) == 0)? FAIL : OK;
2482 rc = (strcmpic(arg, US"no") == 0 ||
2483 strcmpic(arg, US"false") == 0)? FAIL :
2484 (strcmpic(arg, US"yes") == 0 ||
2485 strcmpic(arg, US"true") == 0)? OK : DEFER;
2487 *log_msgptr = string_sprintf("invalid \"condition\" value \"%s\"", arg);
2491 control_type = decode_control(arg, &p, where, log_msgptr);
2493 /* Check if this control makes sense at this time */
2495 if ((control_forbids[control_type] & (1 << where)) != 0)
2497 *log_msgptr = string_sprintf("cannot use \"control=%s\" in %s ACL",
2498 controls[control_type], acl_wherenames[where]);
2502 switch(control_type)
2504 case CONTROL_AUTH_UNADVERTISED:
2505 allow_auth_unadvertised = TRUE;
2508 #ifdef EXPERIMENTAL_BRIGHTMAIL
2509 case CONTROL_BMI_RUN:
2514 #ifdef EXPERIMENTAL_DOMAINKEYS
2515 case CONTROL_DK_VERIFY:
2523 case CONTROL_CASEFUL_LOCAL_PART:
2524 deliver_localpart = addr->cc_local_part;
2527 case CONTROL_CASELOWER_LOCAL_PART:
2528 deliver_localpart = addr->lc_local_part;
2531 case CONTROL_ENFORCE_SYNC:
2532 smtp_enforce_sync = TRUE;
2535 case CONTROL_NO_ENFORCE_SYNC:
2536 smtp_enforce_sync = FALSE;
2539 #ifdef WITH_CONTENT_SCAN
2540 case CONTROL_NO_MBOX_UNSPOOL:
2541 no_mbox_unspool = TRUE;
2545 case CONTROL_NO_MULTILINE:
2546 no_multiline_responses = TRUE;
2549 case CONTROL_FAKEDEFER:
2550 case CONTROL_FAKEREJECT:
2551 fake_response = (control_type == CONTROL_FAKEDEFER) ? DEFER : FAIL;
2555 while (*pp != 0) pp++;
2556 fake_response_text = expand_string(string_copyn(p+1, pp-p-1));
2561 /* Explicitly reset to default string */
2562 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).";
2566 case CONTROL_FREEZE:
2567 deliver_freeze = TRUE;
2568 deliver_frozen_at = time(NULL);
2569 freeze_tell = freeze_tell_config; /* Reset to configured value */
2570 if (Ustrncmp(p, "/no_tell", 8) == 0)
2577 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
2582 case CONTROL_QUEUE_ONLY:
2583 queue_only_policy = TRUE;
2586 case CONTROL_SUBMISSION:
2587 originator_name = US"";
2588 submission_mode = TRUE;
2591 if (Ustrncmp(p, "/sender_retain", 14) == 0)
2594 active_local_sender_retain = TRUE;
2595 active_local_from_check = FALSE;
2597 else if (Ustrncmp(p, "/domain=", 8) == 0)
2600 while (*pp != 0 && *pp != '/') pp++;
2601 submission_domain = string_copyn(p+8, pp-p-8);
2604 /* The name= option must be last, because it swallows the rest of
2606 else if (Ustrncmp(p, "/name=", 6) == 0)
2609 while (*pp != 0) pp++;
2610 submission_name = string_copy(parse_fix_phrase(p+6, pp-p-6,
2611 big_buffer, big_buffer_size));
2618 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
2623 case CONTROL_SUPPRESS_LOCAL_FIXUPS:
2624 suppress_local_fixups = TRUE;
2629 #ifdef WITH_CONTENT_SCAN
2631 rc = mime_decode(&arg);
2637 int delay = readconf_readtime(arg, 0, FALSE);
2640 *log_msgptr = string_sprintf("syntax error in argument for \"delay\" "
2641 "modifier: \"%s\" is not a time value", arg);
2646 HDEBUG(D_acl) debug_printf("delay modifier requests %d-second delay\n",
2651 debug_printf("delay skipped in -bh checking mode\n");
2654 /* It appears to be impossible to detect that a TCP/IP connection has
2655 gone away without reading from it. This means that we cannot shorten
2656 the delay below if the client goes away, because we cannot discover
2657 that the client has closed its end of the connection. (The connection
2658 is actually in a half-closed state, waiting for the server to close its
2659 end.) It would be nice to be able to detect this state, so that the
2660 Exim process is not held up unnecessarily. However, it seems that we
2661 can't. The poll() function does not do the right thing, and in any case
2662 it is not always available.
2664 NOTE: If ever this state of affairs changes, remember that we may be
2665 dealing with stdin/stdout here, in addition to TCP/IP connections.
2666 Whatever is done must work in both cases. To detected the stdin/stdout
2667 case, check for smtp_in or smtp_out being NULL. */
2671 while (delay > 0) delay = sleep(delay);
2677 #ifdef WITH_OLD_DEMIME
2683 #ifdef EXPERIMENTAL_DOMAINKEYS
2684 case ACLC_DK_DOMAIN_SOURCE:
2685 if (dk_verify_block == NULL) { rc = FAIL; break; };
2686 /* check header source of domain against given string */
2687 switch (dk_verify_block->address_source) {
2688 case DK_EXIM_ADDRESS_FROM_FROM:
2689 rc = match_isinlist(US"from", &arg, 0, NULL,
2690 NULL, MCL_STRING, TRUE, NULL);
2692 case DK_EXIM_ADDRESS_FROM_SENDER:
2693 rc = match_isinlist(US"sender", &arg, 0, NULL,
2694 NULL, MCL_STRING, TRUE, NULL);
2696 case DK_EXIM_ADDRESS_NONE:
2697 rc = match_isinlist(US"none", &arg, 0, NULL,
2698 NULL, MCL_STRING, TRUE, NULL);
2703 case ACLC_DK_POLICY:
2704 if (dk_verify_block == NULL) { rc = FAIL; break; };
2705 /* check policy against given string, default FAIL */
2707 if (dk_verify_block->signsall)
2708 rc = match_isinlist(US"signsall", &arg, 0, NULL,
2709 NULL, MCL_STRING, TRUE, NULL);
2710 if (dk_verify_block->testing)
2711 rc = match_isinlist(US"testing", &arg, 0, NULL,
2712 NULL, MCL_STRING, TRUE, NULL);
2715 case ACLC_DK_SENDER_DOMAINS:
2716 if (dk_verify_block == NULL) { rc = FAIL; break; };
2717 if (dk_verify_block->domain != NULL)
2718 rc = match_isinlist(dk_verify_block->domain, &arg, 0, &domainlist_anchor,
2719 NULL, MCL_DOMAIN, TRUE, NULL);
2723 case ACLC_DK_SENDER_LOCAL_PARTS:
2724 if (dk_verify_block == NULL) { rc = FAIL; break; };
2725 if (dk_verify_block->local_part != NULL)
2726 rc = match_isinlist(dk_verify_block->local_part, &arg, 0, &localpartlist_anchor,
2727 NULL, MCL_LOCALPART, TRUE, NULL);
2731 case ACLC_DK_SENDERS:
2732 if (dk_verify_block == NULL) { rc = FAIL; break; };
2733 if (dk_verify_block->address != NULL)
2734 rc = match_address_list(dk_verify_block->address, TRUE, TRUE, &arg, NULL, -1, 0, NULL);
2738 case ACLC_DK_STATUS:
2739 if (dk_verify_block == NULL) { rc = FAIL; break; };
2740 if (dk_verify_block->result > 0) {
2741 switch(dk_verify_block->result) {
2742 case DK_EXIM_RESULT_BAD_FORMAT:
2743 rc = match_isinlist(US"bad format", &arg, 0, NULL,
2744 NULL, MCL_STRING, TRUE, NULL);
2746 case DK_EXIM_RESULT_NO_KEY:
2747 rc = match_isinlist(US"no key", &arg, 0, NULL,
2748 NULL, MCL_STRING, TRUE, NULL);
2750 case DK_EXIM_RESULT_NO_SIGNATURE:
2751 rc = match_isinlist(US"no signature", &arg, 0, NULL,
2752 NULL, MCL_STRING, TRUE, NULL);
2754 case DK_EXIM_RESULT_REVOKED:
2755 rc = match_isinlist(US"revoked", &arg, 0, NULL,
2756 NULL, MCL_STRING, TRUE, NULL);
2758 case DK_EXIM_RESULT_NON_PARTICIPANT:
2759 rc = match_isinlist(US"non-participant", &arg, 0, NULL,
2760 NULL, MCL_STRING, TRUE, NULL);
2762 case DK_EXIM_RESULT_GOOD:
2763 rc = match_isinlist(US"good", &arg, 0, NULL,
2764 NULL, MCL_STRING, TRUE, NULL);
2766 case DK_EXIM_RESULT_BAD:
2767 rc = match_isinlist(US"bad", &arg, 0, NULL,
2768 NULL, MCL_STRING, TRUE, NULL);
2776 rc = verify_check_dnsbl(&arg);
2780 rc = match_isinlist(addr->domain, &arg, 0, &domainlist_anchor,
2781 addr->domain_cache, MCL_DOMAIN, TRUE, &deliver_domain_data);
2784 /* The value in tls_cipher is the full cipher name, for example,
2785 TLSv1:DES-CBC3-SHA:168, whereas the values to test for are just the
2786 cipher names such as DES-CBC3-SHA. But program defensively. We don't know
2787 what may in practice come out of the SSL library - which at the time of
2788 writing is poorly documented. */
2790 case ACLC_ENCRYPTED:
2791 if (tls_cipher == NULL) rc = FAIL; else
2793 uschar *endcipher = NULL;
2794 uschar *cipher = Ustrchr(tls_cipher, ':');
2795 if (cipher == NULL) cipher = tls_cipher; else
2797 endcipher = Ustrchr(++cipher, ':');
2798 if (endcipher != NULL) *endcipher = 0;
2800 rc = match_isinlist(cipher, &arg, 0, NULL, NULL, MCL_STRING, TRUE, NULL);
2801 if (endcipher != NULL) *endcipher = ':';
2805 /* Use verify_check_this_host() instead of verify_check_host() so that
2806 we can pass over &host_data to catch any looked up data. Once it has been
2807 set, it retains its value so that it's still there if another ACL verb
2808 comes through here and uses the cache. However, we must put it into
2809 permanent store in case it is also expected to be used in a subsequent
2810 message in the same SMTP connection. */
2813 rc = verify_check_this_host(&arg, sender_host_cache, NULL,
2814 (sender_host_address == NULL)? US"" : sender_host_address, &host_data);
2815 if (host_data != NULL) host_data = string_copy_malloc(host_data);
2818 case ACLC_LOCAL_PARTS:
2819 rc = match_isinlist(addr->cc_local_part, &arg, 0,
2820 &localpartlist_anchor, addr->localpart_cache, MCL_LOCALPART, TRUE,
2821 &deliver_localpart_data);
2833 if (Ustrncmp(s, "main", 4) == 0)
2834 { logbits |= LOG_MAIN; s += 4; }
2835 else if (Ustrncmp(s, "panic", 5) == 0)
2836 { logbits |= LOG_PANIC; s += 5; }
2837 else if (Ustrncmp(s, "reject", 6) == 0)
2838 { logbits |= LOG_REJECT; s += 6; }
2841 logbits = LOG_MAIN|LOG_PANIC;
2842 s = string_sprintf(":unknown log name in \"%s\" in "
2843 "\"logwrite\" in %s ACL", arg, acl_wherenames[where]);
2849 while (isspace(*s)) s++;
2850 if (logbits == 0) logbits = LOG_MAIN;
2851 log_write(0, logbits, "%s", string_printing(s));
2855 #ifdef WITH_CONTENT_SCAN
2858 /* Seperate the regular expression and any optional parameters. */
2859 uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size);
2860 /* Run the malware backend. */
2862 /* Modify return code based upon the existance of options. */
2863 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2865 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
2867 /* FAIL so that the message is passed to the next ACL */
2874 case ACLC_MIME_REGEX:
2875 rc = mime_regex(&arg);
2879 case ACLC_RATELIMIT:
2880 rc = acl_ratelimit(arg, where, log_msgptr);
2883 case ACLC_RECIPIENTS:
2884 rc = match_address_list(addr->address, TRUE, TRUE, &arg, NULL, -1, 0,
2888 #ifdef WITH_CONTENT_SCAN
2894 case ACLC_SENDER_DOMAINS:
2897 sdomain = Ustrrchr(sender_address, '@');
2898 sdomain = (sdomain == NULL)? US"" : sdomain + 1;
2899 rc = match_isinlist(sdomain, &arg, 0, &domainlist_anchor,
2900 sender_domain_cache, MCL_DOMAIN, TRUE, NULL);
2905 rc = match_address_list(sender_address, TRUE, TRUE, &arg,
2906 sender_address_cache, -1, 0, &sender_data);
2909 /* Connection variables must persist forever */
2913 int old_pool = store_pool;
2914 if (cb->u.varnumber < ACL_CVARS) store_pool = POOL_PERM;
2915 acl_var[cb->u.varnumber] = string_copy(arg);
2916 store_pool = old_pool;
2920 #ifdef WITH_CONTENT_SCAN
2923 /* Seperate the regular expression and any optional parameters. */
2924 uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size);
2925 /* Run the spam backend. */
2927 /* Modify return code based upon the existance of options. */
2928 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2930 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
2932 /* FAIL so that the message is passed to the next ACL */
2940 #ifdef EXPERIMENTAL_SPF
2942 rc = spf_process(&arg, sender_address);
2946 /* If the verb is WARN, discard any user message from verification, because
2947 such messages are SMTP responses, not header additions. The latter come
2948 only from explicit "message" modifiers. However, put the user message into
2949 $acl_verify_message so it can be used in subsequent conditions or modifiers
2950 (until something changes it). */
2953 rc = acl_verify(where, addr, arg, user_msgptr, log_msgptr, basic_errno);
2954 acl_verify_message = *user_msgptr;
2955 if (verb == ACL_WARN) *user_msgptr = NULL;
2959 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown "
2960 "condition %d", cb->type);
2964 /* If a condition was negated, invert OK/FAIL. */
2966 if (!cond_modifiers[cb->type] && cb->u.negated)
2968 if (rc == OK) rc = FAIL;
2969 else if (rc == FAIL || rc == FAIL_DROP) rc = OK;
2972 if (rc != OK) break; /* Conditions loop */
2976 /* If the result is the one for which "message" and/or "log_message" are used,
2977 handle the values of these options. Most verbs have but a single return for
2978 which the messages are relevant, but for "discard", it's useful to have the log
2979 message both when it succeeds and when it fails. Also, for an "accept" that
2980 appears in a QUIT ACL, we want to handle the user message. Since only "accept"
2981 and "warn" are permitted in that ACL, we don't need to test the verb.
2983 These modifiers act in different ways:
2985 "message" is a user message that will be included in an SMTP response. Unless
2986 it is empty, it overrides any previously set user message.
2988 "log_message" is a non-user message, and it adds to any existing non-user
2989 message that is already set.
2991 If there isn't a log message set, we make it the same as the user message. */
2993 if (((rc == FAIL_DROP)? FAIL : rc) == msgcond[verb] ||
2994 (verb == ACL_DISCARD && rc == OK) ||
2995 (where == ACL_WHERE_QUIT))
2999 /* If the verb is "warn", messages generated by conditions (verification or
3000 nested ACLs) are discarded. Only messages specified at this level are used.
3001 However, the value of an existing message is available in $acl_verify_message
3002 during expansions. */
3004 uschar *old_user_msgptr = *user_msgptr;
3005 uschar *old_log_msgptr = (*log_msgptr != NULL)? *log_msgptr : old_user_msgptr;
3007 if (verb == ACL_WARN) *log_msgptr = *user_msgptr = NULL;
3009 if (user_message != NULL)
3011 acl_verify_message = old_user_msgptr;
3012 expmessage = expand_string(user_message);
3013 if (expmessage == NULL)
3015 if (!expand_string_forcedfail)
3016 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
3017 user_message, expand_string_message);
3019 else if (expmessage[0] != 0) *user_msgptr = expmessage;
3022 if (log_message != NULL)
3024 acl_verify_message = old_log_msgptr;
3025 expmessage = expand_string(log_message);
3026 if (expmessage == NULL)
3028 if (!expand_string_forcedfail)
3029 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
3030 log_message, expand_string_message);
3032 else if (expmessage[0] != 0)
3034 *log_msgptr = (*log_msgptr == NULL)? expmessage :
3035 string_sprintf("%s: %s", expmessage, *log_msgptr);
3039 /* If no log message, default it to the user message */
3041 if (*log_msgptr == NULL) *log_msgptr = *user_msgptr;
3044 acl_verify_message = NULL;
3052 /*************************************************
3053 * Get line from a literal ACL *
3054 *************************************************/
3056 /* This function is passed to acl_read() in order to extract individual lines
3057 of a literal ACL, which we access via static pointers. We can destroy the
3058 contents because this is called only once (the compiled ACL is remembered).
3060 This code is intended to treat the data in the same way as lines in the main
3061 Exim configuration file. That is:
3063 . Leading spaces are ignored.
3065 . A \ at the end of a line is a continuation - trailing spaces after the \
3066 are permitted (this is because I don't believe in making invisible things
3067 significant). Leading spaces on the continued part of a line are ignored.
3069 . Physical lines starting (significantly) with # are totally ignored, and
3070 may appear within a sequence of backslash-continued lines.
3072 . Blank lines are ignored, but will end a sequence of continuations.
3075 Returns: a pointer to the next line
3079 static uschar *acl_text; /* Current pointer in the text */
3080 static uschar *acl_text_end; /* Points one past the terminating '0' */
3088 /* This loop handles leading blank lines and comments. */
3092 while (isspace(*acl_text)) acl_text++; /* Leading spaces/empty lines */
3093 if (*acl_text == 0) return NULL; /* No more data */
3094 yield = acl_text; /* Potential data line */
3096 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3098 /* If we hit the end before a newline, we have the whole logical line. If
3099 it's a comment, there's no more data to be given. Otherwise, yield it. */
3101 if (*acl_text == 0) return (*yield == '#')? NULL : yield;
3103 /* After reaching a newline, end this loop if the physical line does not
3104 start with '#'. If it does, it's a comment, and the loop continues. */
3106 if (*yield != '#') break;
3109 /* This loop handles continuations. We know we have some real data, ending in
3110 newline. See if there is a continuation marker at the end (ignoring trailing
3111 white space). We know that *yield is not white space, so no need to test for
3112 cont > yield in the backwards scanning loop. */
3117 for (cont = acl_text - 1; isspace(*cont); cont--);
3119 /* If no continuation follows, we are done. Mark the end of the line and
3128 /* We have encountered a continuation. Skip over whitespace at the start of
3129 the next line, and indeed the whole of the next line or lines if they are
3134 while (*(++acl_text) == ' ' || *acl_text == '\t');
3135 if (*acl_text != '#') break;
3136 while (*(++acl_text) != 0 && *acl_text != '\n');
3139 /* We have the start of a continuation line. Move all the rest of the data
3140 to join onto the previous line, and then find its end. If the end is not a
3141 newline, we are done. Otherwise loop to look for another continuation. */
3143 memmove(cont, acl_text, acl_text_end - acl_text);
3144 acl_text_end -= acl_text - cont;
3146 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3147 if (*acl_text == 0) return yield;
3150 /* Control does not reach here */
3157 /*************************************************
3158 * Check access using an ACL *
3159 *************************************************/
3161 /* This function is called from address_check. It may recurse via
3162 acl_check_condition() - hence the use of a level to stop looping. The ACL is
3163 passed as a string which is expanded. A forced failure implies no access check
3164 is required. If the result is a single word, it is taken as the name of an ACL
3165 which is sought in the global ACL tree. Otherwise, it is taken as literal ACL
3166 text, complete with newlines, and parsed as such. In both cases, the ACL check
3167 is then run. This function uses an auxiliary function for acl_read() to call
3168 for reading individual lines of a literal ACL. This is acl_getline(), which
3169 appears immediately above.
3172 where where called from
3173 addr address item when called from RCPT; otherwise NULL
3174 s the input string; NULL is the same as an empty ACL => DENY
3175 level the nesting level
3176 user_msgptr where to put a user error (for SMTP response)
3177 log_msgptr where to put a logging message (not for SMTP response)
3179 Returns: OK access is granted
3180 DISCARD access is apparently granted...
3181 FAIL access is denied
3182 FAIL_DROP access is denied; drop the connection
3183 DEFER can't tell at the moment
3188 acl_check_internal(int where, address_item *addr, uschar *s, int level,
3189 uschar **user_msgptr, uschar **log_msgptr)
3192 acl_block *acl = NULL;
3193 uschar *acl_name = US"inline ACL";
3196 /* Catch configuration loops */
3200 *log_msgptr = US"ACL nested too deep: possible loop";
3206 HDEBUG(D_acl) debug_printf("ACL is NULL: implicit DENY\n");
3210 /* At top level, we expand the incoming string. At lower levels, it has already
3211 been expanded as part of condition processing. */
3215 ss = expand_string(s);
3218 if (expand_string_forcedfail) return OK;
3219 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s", s,
3220 expand_string_message);
3226 while (isspace(*ss))ss++;
3228 /* If we can't find a named ACL, the default is to parse it as an inline one.
3229 (Unless it begins with a slash; non-existent files give rise to an error.) */
3233 /* Handle the case of a string that does not contain any spaces. Look for a
3234 named ACL among those read from the configuration, or a previously read file.
3235 It is possible that the pointer to the ACL is NULL if the configuration
3236 contains a name with no data. If not found, and the text begins with '/',
3237 read an ACL from a file, and save it so it can be re-used. */
3239 if (Ustrchr(ss, ' ') == NULL)
3241 tree_node *t = tree_search(acl_anchor, ss);
3244 acl = (acl_block *)(t->data.ptr);
3247 HDEBUG(D_acl) debug_printf("ACL \"%s\" is empty: implicit DENY\n", ss);
3250 acl_name = string_sprintf("ACL \"%s\"", ss);
3251 HDEBUG(D_acl) debug_printf("using ACL \"%s\"\n", ss);
3254 else if (*ss == '/')
3256 struct stat statbuf;
3257 fd = Uopen(ss, O_RDONLY, 0);
3260 *log_msgptr = string_sprintf("failed to open ACL file \"%s\": %s", ss,
3265 if (fstat(fd, &statbuf) != 0)
3267 *log_msgptr = string_sprintf("failed to fstat ACL file \"%s\": %s", ss,
3272 acl_text = store_get(statbuf.st_size + 1);
3273 acl_text_end = acl_text + statbuf.st_size + 1;
3275 if (read(fd, acl_text, statbuf.st_size) != statbuf.st_size)
3277 *log_msgptr = string_sprintf("failed to read ACL file \"%s\": %s",
3278 ss, strerror(errno));
3281 acl_text[statbuf.st_size] = 0;
3284 acl_name = string_sprintf("ACL \"%s\"", ss);
3285 HDEBUG(D_acl) debug_printf("read ACL from file %s\n", ss);
3289 /* Parse an ACL that is still in text form. If it came from a file, remember it
3290 in the ACL tree, having read it into the POOL_PERM store pool so that it
3291 persists between multiple messages. */
3295 int old_pool = store_pool;
3296 if (fd >= 0) store_pool = POOL_PERM;
3297 acl = acl_read(acl_getline, log_msgptr);
3298 store_pool = old_pool;
3299 if (acl == NULL && *log_msgptr != NULL) return ERROR;
3302 tree_node *t = store_get_perm(sizeof(tree_node) + Ustrlen(ss));
3303 Ustrcpy(t->name, ss);
3305 (void)tree_insertnode(&acl_anchor, t);
3309 /* Now we have an ACL to use. It's possible it may be NULL. */
3314 int basic_errno = 0;
3315 BOOL endpass_seen = FALSE;
3317 *log_msgptr = *user_msgptr = NULL;
3318 acl_temp_details = FALSE;
3320 if (where == ACL_WHERE_QUIT &&
3321 acl->verb != ACL_ACCEPT &&
3322 acl->verb != ACL_WARN)
3324 *log_msgptr = string_sprintf("\"%s\" is not allowed in a QUIT ACL",
3329 HDEBUG(D_acl) debug_printf("processing \"%s\"\n", verbs[acl->verb]);
3331 /* Clear out any search error message from a previous check before testing
3334 search_error_message = NULL;
3335 cond = acl_check_condition(acl->verb, acl->condition, where, addr, level,
3336 &endpass_seen, user_msgptr, log_msgptr, &basic_errno);
3338 /* Handle special returns: DEFER causes a return except on a WARN verb;
3339 ERROR always causes a return. */
3344 HDEBUG(D_acl) debug_printf("%s: condition test deferred\n", verbs[acl->verb]);
3345 if (basic_errno != ERRNO_CALLOUTDEFER)
3347 if (search_error_message != NULL && *search_error_message != 0)
3348 *log_msgptr = search_error_message;
3349 if (smtp_return_error_details) acl_temp_details = TRUE;
3353 acl_temp_details = TRUE;
3355 if (acl->verb != ACL_WARN) return DEFER;
3358 default: /* Paranoia */
3360 HDEBUG(D_acl) debug_printf("%s: condition test error\n", verbs[acl->verb]);
3364 HDEBUG(D_acl) debug_printf("%s: condition test succeeded\n",
3369 HDEBUG(D_acl) debug_printf("%s: condition test failed\n", verbs[acl->verb]);
3372 /* DISCARD and DROP can happen only from a nested ACL condition, and
3373 DISCARD can happen only for an "accept" or "discard" verb. */
3376 HDEBUG(D_acl) debug_printf("%s: condition test yielded \"discard\"\n",
3381 HDEBUG(D_acl) debug_printf("%s: condition test yielded \"drop\"\n",
3386 /* At this point, cond for most verbs is either OK or FAIL or (as a result of
3387 a nested ACL condition) FAIL_DROP. However, for WARN, cond may be DEFER, and
3388 for ACCEPT and DISCARD, it may be DISCARD after a nested ACL call. */
3393 if (cond == OK || cond == DISCARD) return cond;
3396 HDEBUG(D_acl) debug_printf("accept: endpass encountered - denying access\n");
3404 acl_temp_details = TRUE;
3410 if (cond == OK) return FAIL;
3414 if (cond == OK || cond == DISCARD) return DISCARD;
3417 HDEBUG(D_acl) debug_printf("discard: endpass encountered - denying access\n");
3423 if (cond == OK) return FAIL_DROP;
3427 if (cond != OK) return cond;
3432 acl_warn(where, *user_msgptr, *log_msgptr);
3433 else if (cond == DEFER && (log_extra_selector & LX_acl_warn_skipped) != 0)
3434 log_write(0, LOG_MAIN, "%s Warning: ACL \"warn\" statement skipped: "
3435 "condition test deferred%s%s", host_and_ident(TRUE),
3436 (*log_msgptr == NULL)? US"" : US": ",
3437 (*log_msgptr == NULL)? US"" : *log_msgptr);
3438 *log_msgptr = *user_msgptr = NULL; /* In case implicit DENY follows */
3442 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown verb %d",
3447 /* Pass to the next ACL item */
3452 /* We have reached the end of the ACL. This is an implicit DENY. */
3454 HDEBUG(D_acl) debug_printf("end of %s: implicit DENY\n", acl_name);
3459 /*************************************************
3460 * Check access using an ACL *
3461 *************************************************/
3463 /* This is the external interface for ACL checks. It sets up an address and the
3464 expansions for $domain and $local_part when called after RCPT, then calls
3465 acl_check_internal() to do the actual work.
3468 where ACL_WHERE_xxxx indicating where called from
3469 recipient RCPT address for RCPT check, else NULL
3470 s the input string; NULL is the same as an empty ACL => DENY
3471 user_msgptr where to put a user error (for SMTP response)
3472 log_msgptr where to put a logging message (not for SMTP response)
3474 Returns: OK access is granted by an ACCEPT verb
3475 DISCARD access is granted by a DISCARD verb
3476 FAIL access is denied
3477 FAIL_DROP access is denied; drop the connection
3478 DEFER can't tell at the moment
3483 acl_check(int where, uschar *recipient, uschar *s, uschar **user_msgptr,
3484 uschar **log_msgptr)
3488 address_item *addr = NULL;
3490 *user_msgptr = *log_msgptr = NULL;
3491 sender_verified_failed = NULL;
3492 ratelimiters_cmd = NULL;
3494 if (where == ACL_WHERE_RCPT)
3496 adb = address_defaults;
3498 addr->address = recipient;
3499 if (deliver_split_address(addr) == DEFER)
3501 *log_msgptr = US"defer in percent_hack_domains check";
3504 deliver_domain = addr->domain;
3505 deliver_localpart = addr->local_part;
3508 rc = acl_check_internal(where, addr, s, 0, user_msgptr, log_msgptr);
3510 deliver_domain = deliver_localpart = deliver_address_data =
3511 sender_address_data = NULL;
3513 /* A DISCARD response is permitted only for message ACLs, excluding the PREDATA
3514 ACL, which is really in the middle of an SMTP command. */
3518 if (where > ACL_WHERE_NOTSMTP || where == ACL_WHERE_PREDATA)
3520 log_write(0, LOG_MAIN|LOG_PANIC, "\"discard\" verb not allowed in %s "
3521 "ACL", acl_wherenames[where]);
3527 /* A DROP response is not permitted from MAILAUTH */
3529 if (rc == FAIL_DROP && where == ACL_WHERE_MAILAUTH)
3531 log_write(0, LOG_MAIN|LOG_PANIC, "\"drop\" verb not allowed in %s "
3532 "ACL", acl_wherenames[where]);
3536 /* Before giving an error response, take a look at the length of any user
3537 message, and split it up into multiple lines if possible. */
3539 if (rc != OK && *user_msgptr != NULL && Ustrlen(*user_msgptr) > 75)
3541 uschar *s = *user_msgptr = string_copy(*user_msgptr);
3547 while (i < 75 && *ss != 0 && *ss != '\n') ss++, i++;
3548 if (*ss == 0) break;
3555 while (--t > s + 35)
3559 if (t[-1] == ':') { tt = t; break; }
3560 if (tt == NULL) tt = t;
3564 if (tt == NULL) /* Can't split behind - try ahead */
3569 if (*t == ' ' || *t == '\n')
3575 if (tt == NULL) break; /* Can't find anywhere to split */