1 /* $Cambridge: exim/src/src/acl.c,v 1.66 2006/09/25 10:14:20 ph10 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,
68 ACLC_LOG_REJECT_TARGET,
70 #ifdef WITH_CONTENT_SCAN
74 #ifdef WITH_CONTENT_SCAN
79 #ifdef WITH_CONTENT_SCAN
85 #ifdef WITH_CONTENT_SCAN
88 #ifdef EXPERIMENTAL_SPF
93 /* ACL conditions/modifiers: "delay", "control", "endpass", "message",
94 "log_message", "log_reject_target", "logwrite", and "set" are modifiers that
95 look like conditions but always return TRUE. They are used for their side
98 static uschar *conditions[] = {
102 #ifdef EXPERIMENTAL_BRIGHTMAIL
107 #ifdef WITH_CONTENT_SCAN
111 #ifdef WITH_OLD_DEMIME
114 #ifdef EXPERIMENTAL_DOMAINKEYS
115 US"dk_domain_source",
117 US"dk_sender_domains",
118 US"dk_sender_local_parts",
129 US"log_reject_target",
131 #ifdef WITH_CONTENT_SCAN
135 #ifdef WITH_CONTENT_SCAN
140 #ifdef WITH_CONTENT_SCAN
143 US"sender_domains", US"senders", US"set",
144 #ifdef WITH_CONTENT_SCAN
147 #ifdef EXPERIMENTAL_SPF
153 /* Return values from decode_control(); keep in step with the table of names
157 CONTROL_AUTH_UNADVERTISED,
158 #ifdef EXPERIMENTAL_BRIGHTMAIL
161 #ifdef EXPERIMENTAL_DOMAINKEYS
165 CONTROL_CASEFUL_LOCAL_PART,
166 CONTROL_CASELOWER_LOCAL_PART,
167 CONTROL_ENFORCE_SYNC,
168 CONTROL_NO_ENFORCE_SYNC,
172 CONTROL_SUPPRESS_LOCAL_FIXUPS,
173 #ifdef WITH_CONTENT_SCAN
174 CONTROL_NO_MBOX_UNSPOOL,
181 /* ACL control names; keep in step with the table above! This list is used for
182 turning ids into names. The actual list of recognized names is in the variable
183 control_def controls_list[] below. The fact that there are two lists is a mess
184 and should be tidied up. */
186 static uschar *controls[] = {
187 US"allow_auth_unadvertised",
188 #ifdef EXPERIMENTAL_BRIGHTMAIL
191 #ifdef EXPERIMENTAL_DOMAINKEYS
195 US"caseful_local_part",
196 US"caselower_local_part",
202 US"suppress_local_fixups",
203 #ifdef WITH_CONTENT_SCAN
209 /* Flags to indicate for which conditions /modifiers a string expansion is done
210 at the outer level. In the other cases, expansion already occurs in the
211 checking functions. */
213 static uschar cond_expand_at_top[] = {
215 TRUE, /* add_header */
216 FALSE, /* authenticated */
217 #ifdef EXPERIMENTAL_BRIGHTMAIL
218 TRUE, /* bmi_optin */
220 TRUE, /* condition */
222 #ifdef WITH_CONTENT_SCAN
226 #ifdef WITH_OLD_DEMIME
229 #ifdef EXPERIMENTAL_DOMAINKEYS
230 TRUE, /* dk_domain_source */
231 TRUE, /* dk_policy */
232 TRUE, /* dk_sender_domains */
233 TRUE, /* dk_sender_local_parts */
234 TRUE, /* dk_senders */
235 TRUE, /* dk_status */
239 FALSE, /* encrypted */
242 FALSE, /* local_parts */
243 TRUE, /* log_message */
244 TRUE, /* log_reject_target */
246 #ifdef WITH_CONTENT_SCAN
250 #ifdef WITH_CONTENT_SCAN
251 TRUE, /* mime_regex */
253 TRUE, /* ratelimit */
254 FALSE, /* recipients */
255 #ifdef WITH_CONTENT_SCAN
258 FALSE, /* sender_domains */
261 #ifdef WITH_CONTENT_SCAN
264 #ifdef EXPERIMENTAL_SPF
270 /* Flags to identify the modifiers */
272 static uschar cond_modifiers[] = {
274 TRUE, /* add_header */
275 FALSE, /* authenticated */
276 #ifdef EXPERIMENTAL_BRIGHTMAIL
277 TRUE, /* bmi_optin */
279 FALSE, /* condition */
281 #ifdef WITH_CONTENT_SCAN
285 #ifdef WITH_OLD_DEMIME
288 #ifdef EXPERIMENTAL_DOMAINKEYS
289 FALSE, /* dk_domain_source */
290 FALSE, /* dk_policy */
291 FALSE, /* dk_sender_domains */
292 FALSE, /* dk_sender_local_parts */
293 FALSE, /* dk_senders */
294 FALSE, /* dk_status */
296 FALSE, /* dnslists */
298 FALSE, /* encrypted */
301 FALSE, /* local_parts */
302 TRUE, /* log_message */
303 TRUE, /* log_reject_target */
305 #ifdef WITH_CONTENT_SCAN
309 #ifdef WITH_CONTENT_SCAN
310 FALSE, /* mime_regex */
312 FALSE, /* ratelimit */
313 FALSE, /* recipients */
314 #ifdef WITH_CONTENT_SCAN
317 FALSE, /* sender_domains */
320 #ifdef WITH_CONTENT_SCAN
323 #ifdef EXPERIMENTAL_SPF
329 /* Bit map vector of which conditions are not allowed at certain times. For
330 each condition, there's a bitmap of dis-allowed times. For some, it is easier
331 to specify the negation of a small number of allowed times. */
333 static unsigned int cond_forbids[] = {
337 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* add_header */
338 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
339 (1<<ACL_WHERE_MIME)|(1<<ACL_WHERE_NOTSMTP)|
340 (1<<ACL_WHERE_NOTSMTP_START)),
342 (1<<ACL_WHERE_NOTSMTP)| /* authenticated */
343 (1<<ACL_WHERE_NOTSMTP_START)|
344 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO),
346 #ifdef EXPERIMENTAL_BRIGHTMAIL
347 (1<<ACL_WHERE_AUTH)| /* bmi_optin */
348 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
349 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_MIME)|
350 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
351 (1<<ACL_WHERE_MAILAUTH)|
352 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
353 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_PREDATA)|
354 (1<<ACL_WHERE_NOTSMTP_START),
359 /* Certain types of control are always allowed, so we let it through
360 always and check in the control processing itself. */
364 #ifdef WITH_CONTENT_SCAN
366 ~(1<<ACL_WHERE_MIME), /* decode */
371 #ifdef WITH_OLD_DEMIME
373 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)), /* demime */
376 #ifdef EXPERIMENTAL_DOMAINKEYS
377 (1<<ACL_WHERE_AUTH)| /* dk_domain_source */
378 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
379 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
380 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
381 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
382 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
383 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_NOTSMTP_START),
385 (1<<ACL_WHERE_AUTH)| /* dk_policy */
386 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
387 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
388 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
389 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
390 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
391 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_NOTSMTP_START),
393 (1<<ACL_WHERE_AUTH)| /* dk_sender_domains */
394 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
395 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
396 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
397 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
398 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
399 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_NOTSMTP_START),
401 (1<<ACL_WHERE_AUTH)| /* dk_sender_local_parts */
402 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
403 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
404 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
405 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
406 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
407 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_NOTSMTP_START),
409 (1<<ACL_WHERE_AUTH)| /* dk_senders */
410 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
411 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
412 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
413 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
414 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
415 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_NOTSMTP_START),
417 (1<<ACL_WHERE_AUTH)| /* dk_status */
418 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
419 (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
420 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
421 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
422 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
423 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_NOTSMTP_START),
426 (1<<ACL_WHERE_NOTSMTP)| /* dnslists */
427 (1<<ACL_WHERE_NOTSMTP_START),
430 ~(1<<ACL_WHERE_RCPT), /* domains */
432 (1<<ACL_WHERE_NOTSMTP)| /* encrypted */
433 (1<<ACL_WHERE_CONNECT)|
434 (1<<ACL_WHERE_NOTSMTP_START)|
439 (1<<ACL_WHERE_NOTSMTP)| /* hosts */
440 (1<<ACL_WHERE_NOTSMTP_START),
443 ~(1<<ACL_WHERE_RCPT), /* local_parts */
447 0, /* log_reject_target */
451 #ifdef WITH_CONTENT_SCAN
453 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)), /* malware */
458 #ifdef WITH_CONTENT_SCAN
460 ~(1<<ACL_WHERE_MIME), /* mime_regex */
466 ~(1<<ACL_WHERE_RCPT), /* recipients */
468 #ifdef WITH_CONTENT_SCAN
470 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* regex */
471 (1<<ACL_WHERE_MIME)),
474 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* sender_domains */
476 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
477 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
478 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
480 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* senders */
482 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
483 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
484 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
488 #ifdef WITH_CONTENT_SCAN
490 ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)), /* spam */
493 #ifdef EXPERIMENTAL_SPF
494 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* spf */
496 (1<<ACL_WHERE_MAILAUTH)|
497 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
498 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY)|
499 (1<<ACL_WHERE_NOTSMTP)|
500 (1<<ACL_WHERE_NOTSMTP_START),
503 /* Certain types of verify are always allowed, so we let it through
504 always and check in the verify function itself */
510 /* Bit map vector of which controls are not allowed at certain times. For
511 each control, there's a bitmap of dis-allowed times. For some, it is easier to
512 specify the negation of a small number of allowed times. */
514 static unsigned int control_forbids[] = {
516 ~((1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)), /* allow_auth_unadvertised */
518 #ifdef EXPERIMENTAL_BRIGHTMAIL
522 #ifdef EXPERIMENTAL_DOMAINKEYS
523 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* dk_verify */
524 (1<<ACL_WHERE_NOTSMTP_START),
530 ~(1<<ACL_WHERE_RCPT), /* caseful_local_part */
533 ~(1<<ACL_WHERE_RCPT), /* caselower_local_part */
535 (1<<ACL_WHERE_NOTSMTP)| /* enforce_sync */
536 (1<<ACL_WHERE_NOTSMTP_START),
538 (1<<ACL_WHERE_NOTSMTP)| /* no_enforce_sync */
539 (1<<ACL_WHERE_NOTSMTP_START),
542 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* freeze */
543 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
544 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)),
547 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* queue_only */
548 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
549 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)),
552 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* submission */
553 (1<<ACL_WHERE_PREDATA)),
556 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* suppress_local_fixups */
557 (1<<ACL_WHERE_PREDATA)|
558 (1<<ACL_WHERE_NOTSMTP_START)),
560 #ifdef WITH_CONTENT_SCAN
562 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* no_mbox_unspool */
563 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
564 (1<<ACL_WHERE_MIME)),
568 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakedefer */
569 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
570 (1<<ACL_WHERE_MIME)),
573 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakereject */
574 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
575 (1<<ACL_WHERE_MIME)),
577 (1<<ACL_WHERE_NOTSMTP)| /* no_multiline */
578 (1<<ACL_WHERE_NOTSMTP_START)
581 /* Structure listing various control arguments, with their characteristics. */
583 typedef struct control_def {
585 int value; /* CONTROL_xxx value */
586 BOOL has_option; /* Has /option(s) following */
589 static control_def controls_list[] = {
590 { US"allow_auth_unadvertised", CONTROL_AUTH_UNADVERTISED, FALSE },
591 #ifdef EXPERIMENTAL_BRIGHTMAIL
592 { US"bmi_run", CONTROL_BMI_RUN, FALSE },
594 #ifdef EXPERIMENTAL_DOMAINKEYS
595 { US"dk_verify", CONTROL_DK_VERIFY, FALSE },
597 { US"caseful_local_part", CONTROL_CASEFUL_LOCAL_PART, FALSE },
598 { US"caselower_local_part", CONTROL_CASELOWER_LOCAL_PART, FALSE },
599 { US"enforce_sync", CONTROL_ENFORCE_SYNC, FALSE },
600 { US"freeze", CONTROL_FREEZE, TRUE },
601 { US"no_enforce_sync", CONTROL_NO_ENFORCE_SYNC, FALSE },
602 { US"no_multiline_responses", CONTROL_NO_MULTILINE, FALSE },
603 { US"queue_only", CONTROL_QUEUE_ONLY, FALSE },
604 #ifdef WITH_CONTENT_SCAN
605 { US"no_mbox_unspool", CONTROL_NO_MBOX_UNSPOOL, FALSE },
607 { US"fakedefer", CONTROL_FAKEDEFER, TRUE },
608 { US"fakereject", CONTROL_FAKEREJECT, TRUE },
609 { US"submission", CONTROL_SUBMISSION, TRUE },
610 { US"suppress_local_fixups", CONTROL_SUPPRESS_LOCAL_FIXUPS, FALSE }
613 /* Support data structures for Client SMTP Authorization. acl_verify_csa()
614 caches its result in a tree to avoid repeated DNS queries. The result is an
615 integer code which is used as an index into the following tables of
616 explanatory strings and verification return codes. */
618 static tree_node *csa_cache = NULL;
620 enum { CSA_UNKNOWN, CSA_OK, CSA_DEFER_SRV, CSA_DEFER_ADDR,
621 CSA_FAIL_EXPLICIT, CSA_FAIL_DOMAIN, CSA_FAIL_NOADDR, CSA_FAIL_MISMATCH };
623 /* The acl_verify_csa() return code is translated into an acl_verify() return
624 code using the following table. It is OK unless the client is definitely not
625 authorized. This is because CSA is supposed to be optional for sending sites,
626 so recipients should not be too strict about checking it - especially because
627 DNS problems are quite likely to occur. It's possible to use $csa_status in
628 further ACL conditions to distinguish ok, unknown, and defer if required, but
629 the aim is to make the usual configuration simple. */
631 static int csa_return_code[] = {
633 FAIL, FAIL, FAIL, FAIL
636 static uschar *csa_status_string[] = {
637 US"unknown", US"ok", US"defer", US"defer",
638 US"fail", US"fail", US"fail", US"fail"
641 static uschar *csa_reason_string[] = {
644 US"deferred (SRV lookup failed)",
645 US"deferred (target address lookup failed)",
646 US"failed (explicit authorization required)",
647 US"failed (host name not authorized)",
648 US"failed (no authorized addresses)",
649 US"failed (client address mismatch)"
652 /* Enable recursion between acl_check_internal() and acl_check_condition() */
654 static int acl_check_internal(int, address_item *, uschar *, int, uschar **,
658 /*************************************************
659 * Pick out name from list *
660 *************************************************/
662 /* Use a binary chop method
669 Returns: offset in list, or -1 if not found
673 acl_checkname(uschar *name, uschar **list, int end)
679 int mid = (start + end)/2;
680 int c = Ustrcmp(name, list[mid]);
681 if (c == 0) return mid;
682 if (c < 0) end = mid; else start = mid + 1;
689 /*************************************************
690 * Read and parse one ACL *
691 *************************************************/
693 /* This function is called both from readconf in order to parse the ACLs in the
694 configuration file, and also when an ACL is encountered dynamically (e.g. as
695 the result of an expansion). It is given a function to call in order to
696 retrieve the lines of the ACL. This function handles skipping comments and
697 blank lines (where relevant).
700 func function to get next line of ACL
701 error where to put an error message
703 Returns: pointer to ACL, or NULL
704 NULL can be legal (empty ACL); in this case error will be NULL
708 acl_read(uschar *(*func)(void), uschar **error)
710 acl_block *yield = NULL;
711 acl_block **lastp = &yield;
712 acl_block *this = NULL;
713 acl_condition_block *cond;
714 acl_condition_block **condp = NULL;
719 while ((s = (*func)()) != NULL)
722 BOOL negated = FALSE;
723 uschar *saveline = s;
726 /* Conditions (but not verbs) are allowed to be negated by an initial
729 while (isspace(*s)) s++;
736 /* Read the name of a verb or a condition, or the start of a new ACL, which
737 can be started by a name, or by a macro definition. */
739 s = readconf_readname(name, sizeof(name), s);
740 if (*s == ':' || (isupper(name[0]) && *s == '=')) return yield;
742 /* If a verb is unrecognized, it may be another condition or modifier that
743 continues the previous verb. */
745 v = acl_checkname(name, verbs, sizeof(verbs)/sizeof(char *));
750 *error = string_sprintf("unknown ACL verb \"%s\" in \"%s\"", name,
762 *error = string_sprintf("malformed ACL line \"%s\"", saveline);
765 this = store_get(sizeof(acl_block));
767 lastp = &(this->next);
770 this->condition = NULL;
771 condp = &(this->condition);
772 if (*s == 0) continue; /* No condition on this line */
778 s = readconf_readname(name, sizeof(name), s); /* Condition name */
781 /* Handle a condition or modifier. */
783 c = acl_checkname(name, conditions, sizeof(conditions)/sizeof(char *));
786 *error = string_sprintf("unknown ACL condition/modifier in \"%s\"",
791 /* The modifiers may not be negated */
793 if (negated && cond_modifiers[c])
795 *error = string_sprintf("ACL error: negation is not allowed with "
796 "\"%s\"", conditions[c]);
800 /* ENDPASS may occur only with ACCEPT or DISCARD. */
802 if (c == ACLC_ENDPASS &&
803 this->verb != ACL_ACCEPT &&
804 this->verb != ACL_DISCARD)
806 *error = string_sprintf("ACL error: \"%s\" is not allowed with \"%s\"",
807 conditions[c], verbs[this->verb]);
811 cond = store_get(sizeof(acl_condition_block));
814 cond->u.negated = negated;
817 condp = &(cond->next);
819 /* The "set" modifier is different in that its argument is "name=value"
820 rather than just a value, and we can check the validity of the name, which
821 gives us a variable name to insert into the data block. The original ACL
822 variable names were acl_c0 ... acl_c9 and acl_m0 ... acl_m9. This was
823 extended to 20 of each type, but after that people successfully argued for
824 arbitrary names. In the new scheme, the names must start with acl_c or acl_m.
825 After that, we allow alphanumerics and underscores, but the first character
826 after c or m must be a digit or an underscore. This retains backwards
833 if (Ustrncmp(s, "acl_c", 5) != 0 &&
834 Ustrncmp(s, "acl_m", 5) != 0)
836 *error = string_sprintf("invalid variable name after \"set\" in ACL "
837 "modifier \"set %s\" (must start \"acl_c\" or \"acl_m\")", s);
842 if (!isdigit(*endptr) && *endptr != '_')
844 *error = string_sprintf("invalid variable name after \"set\" in ACL "
845 "modifier \"set %s\" (digit or underscore must follow acl_c or acl_m)",
850 while (*endptr != 0 && *endptr != '=' && !isspace(*endptr))
852 if (!isalnum(*endptr) && *endptr != '_')
854 *error = string_sprintf("invalid character \"%c\" in variable name "
855 "in ACL modifier \"set %s\"", *endptr, s);
861 cond->u.varname = string_copyn(s + 4, endptr - s - 4);
863 while (isspace(*s)) s++;
866 /* For "set", we are now positioned for the data. For the others, only
867 "endpass" has no data */
869 if (c != ACLC_ENDPASS)
873 *error = string_sprintf("\"=\" missing after ACL \"%s\" %s", name,
874 cond_modifiers[c]? US"modifier" : US"condition");
877 while (isspace(*s)) s++;
878 cond->arg = string_copy(s);
887 /*************************************************
888 * Set up added header line(s) *
889 *************************************************/
891 /* This function is called by the add_header modifier, and also from acl_warn()
892 to implement the now-deprecated way of adding header lines using "message" on a
893 "warn" verb. The argument is treated as a sequence of header lines which are
894 added to a chain, provided there isn't an identical one already there.
896 Argument: string of header lines
901 setup_header(uschar *hstring)
904 int hlen = Ustrlen(hstring);
906 /* An empty string does nothing; otherwise add a final newline if necessary. */
908 if (hlen <= 0) return;
909 if (hstring[hlen-1] != '\n') hstring = string_sprintf("%s\n", hstring);
911 /* Loop for multiple header lines, taking care about continuations */
913 for (p = q = hstring; *p != 0; )
916 int newtype = htype_add_bot;
917 header_line **hptr = &acl_added_headers;
919 /* Find next header line within the string */
923 q = Ustrchr(q, '\n');
924 if (*(++q) != ' ' && *q != '\t') break;
927 /* If the line starts with a colon, interpret the instruction for where to
928 add it. This temporarily sets up a new type. */
932 if (strncmpic(p, US":after_received:", 16) == 0)
934 newtype = htype_add_rec;
937 else if (strncmpic(p, US":at_start_rfc:", 14) == 0)
939 newtype = htype_add_rfc;
942 else if (strncmpic(p, US":at_start:", 10) == 0)
944 newtype = htype_add_top;
947 else if (strncmpic(p, US":at_end:", 8) == 0)
949 newtype = htype_add_bot;
952 while (*p == ' ' || *p == '\t') p++;
955 /* See if this line starts with a header name, and if not, add X-ACL-Warn:
956 to the front of it. */
958 for (s = p; s < q - 1; s++)
960 if (*s == ':' || !isgraph(*s)) break;
963 s = string_sprintf("%s%.*s", (*s == ':')? "" : "X-ACL-Warn: ", q - p, p);
966 /* See if this line has already been added */
968 while (*hptr != NULL)
970 if (Ustrncmp((*hptr)->text, s, hlen) == 0) break;
971 hptr = &((*hptr)->next);
974 /* Add if not previously present */
978 header_line *h = store_get(sizeof(header_line));
987 /* Advance for next header line within the string */
996 /*************************************************
998 *************************************************/
1000 /* This function is called when a WARN verb's conditions are true. It adds to
1001 the message's headers, and/or writes information to the log. In each case, this
1002 only happens once (per message for headers, per connection for log).
1004 ** NOTE: The header adding action using the "message" setting is historic, and
1005 its use is now deprecated. The new add_header modifier should be used instead.
1008 where ACL_WHERE_xxxx indicating which ACL this is
1009 user_message message for adding to headers
1010 log_message message for logging, if different
1016 acl_warn(int where, uschar *user_message, uschar *log_message)
1018 if (log_message != NULL && log_message != user_message)
1021 string_item *logged;
1023 text = string_sprintf("%s Warning: %s", host_and_ident(TRUE),
1024 string_printing(log_message));
1026 /* If a sender verification has failed, and the log message is "sender verify
1027 failed", add the failure message. */
1029 if (sender_verified_failed != NULL &&
1030 sender_verified_failed->message != NULL &&
1031 strcmpic(log_message, US"sender verify failed") == 0)
1032 text = string_sprintf("%s: %s", text, sender_verified_failed->message);
1034 /* Search previously logged warnings. They are kept in malloc
1035 store so they can be freed at the start of a new message. */
1037 for (logged = acl_warn_logged; logged != NULL; logged = logged->next)
1038 if (Ustrcmp(logged->text, text) == 0) break;
1042 int length = Ustrlen(text) + 1;
1043 log_write(0, LOG_MAIN, "%s", text);
1044 logged = store_malloc(sizeof(string_item) + length);
1045 logged->text = (uschar *)logged + sizeof(string_item);
1046 memcpy(logged->text, text, length);
1047 logged->next = acl_warn_logged;
1048 acl_warn_logged = logged;
1052 /* If there's no user message, we are done. */
1054 if (user_message == NULL) return;
1056 /* If this isn't a message ACL, we can't do anything with a user message.
1059 if (where > ACL_WHERE_NOTSMTP)
1061 log_write(0, LOG_MAIN|LOG_PANIC, "ACL \"warn\" with \"message\" setting "
1062 "found in a non-message (%s) ACL: cannot specify header lines here: "
1063 "message ignored", acl_wherenames[where]);
1067 /* The code for setting up header lines is now abstracted into a separate
1068 function so that it can be used for the add_header modifier as well. */
1070 setup_header(user_message);
1075 /*************************************************
1076 * Verify and check reverse DNS *
1077 *************************************************/
1079 /* Called from acl_verify() below. We look up the host name(s) of the client IP
1080 address if this has not yet been done. The host_name_lookup() function checks
1081 that one of these names resolves to an address list that contains the client IP
1082 address, so we don't actually have to do the check here.
1085 user_msgptr pointer for user message
1086 log_msgptr pointer for log message
1088 Returns: OK verification condition succeeded
1089 FAIL verification failed
1090 DEFER there was a problem verifying
1094 acl_verify_reverse(uschar **user_msgptr, uschar **log_msgptr)
1098 user_msgptr = user_msgptr; /* stop compiler warning */
1100 /* Previous success */
1102 if (sender_host_name != NULL) return OK;
1104 /* Previous failure */
1106 if (host_lookup_failed)
1108 *log_msgptr = string_sprintf("host lookup failed%s", host_lookup_msg);
1112 /* Need to do a lookup */
1115 debug_printf("looking up host name to force name/address consistency check\n");
1117 if ((rc = host_name_lookup()) != OK)
1119 *log_msgptr = (rc == DEFER)?
1120 US"host lookup deferred for reverse lookup check"
1122 string_sprintf("host lookup failed for reverse lookup check%s",
1124 return rc; /* DEFER or FAIL */
1127 host_build_sender_fullhost();
1133 /*************************************************
1134 * Check client IP address matches CSA target *
1135 *************************************************/
1137 /* Called from acl_verify_csa() below. This routine scans a section of a DNS
1138 response for address records belonging to the CSA target hostname. The section
1139 is specified by the reset argument, either RESET_ADDITIONAL or RESET_ANSWERS.
1140 If one of the addresses matches the client's IP address, then the client is
1141 authorized by CSA. If there are target IP addresses but none of them match
1142 then the client is using an unauthorized IP address. If there are no target IP
1143 addresses then the client cannot be using an authorized IP address. (This is
1144 an odd configuration - why didn't the SRV record have a weight of 1 instead?)
1147 dnsa the DNS answer block
1148 dnss a DNS scan block for us to use
1149 reset option specifing what portion to scan, as described above
1150 target the target hostname to use for matching RR names
1152 Returns: CSA_OK successfully authorized
1153 CSA_FAIL_MISMATCH addresses found but none matched
1154 CSA_FAIL_NOADDR no target addresses found
1158 acl_verify_csa_address(dns_answer *dnsa, dns_scan *dnss, int reset,
1164 BOOL target_found = FALSE;
1166 for (rr = dns_next_rr(dnsa, dnss, reset);
1168 rr = dns_next_rr(dnsa, dnss, RESET_NEXT))
1170 /* Check this is an address RR for the target hostname. */
1174 && rr->type != T_AAAA
1181 if (strcmpic(target, rr->name) != 0) continue;
1183 target_found = TRUE;
1185 /* Turn the target address RR into a list of textual IP addresses and scan
1186 the list. There may be more than one if it is an A6 RR. */
1188 for (da = dns_address_from_rr(dnsa, rr); da != NULL; da = da->next)
1190 /* If the client IP address matches the target IP address, it's good! */
1192 DEBUG(D_acl) debug_printf("CSA target address is %s\n", da->address);
1194 if (strcmpic(sender_host_address, da->address) == 0) return CSA_OK;
1198 /* If we found some target addresses but none of them matched, the client is
1199 using an unauthorized IP address, otherwise the target has no authorized IP
1202 if (target_found) return CSA_FAIL_MISMATCH;
1203 else return CSA_FAIL_NOADDR;
1208 /*************************************************
1209 * Verify Client SMTP Authorization *
1210 *************************************************/
1212 /* Called from acl_verify() below. This routine calls dns_lookup_special()
1213 to find the CSA SRV record corresponding to the domain argument, or
1214 $sender_helo_name if no argument is provided. It then checks that the
1215 client is authorized, and that its IP address corresponds to the SRV
1216 target's address by calling acl_verify_csa_address() above. The address
1217 should have been returned in the DNS response's ADDITIONAL section, but if
1218 not we perform another DNS lookup to get it.
1221 domain pointer to optional parameter following verify = csa
1223 Returns: CSA_UNKNOWN no valid CSA record found
1224 CSA_OK successfully authorized
1225 CSA_FAIL_* client is definitely not authorized
1226 CSA_DEFER_* there was a DNS problem
1230 acl_verify_csa(uschar *domain)
1234 int priority, weight, port;
1241 /* Work out the domain we are using for the CSA lookup. The default is the
1242 client's HELO domain. If the client has not said HELO, use its IP address
1243 instead. If it's a local client (exim -bs), CSA isn't applicable. */
1245 while (isspace(*domain) && *domain != '\0') ++domain;
1246 if (*domain == '\0') domain = sender_helo_name;
1247 if (domain == NULL) domain = sender_host_address;
1248 if (sender_host_address == NULL) return CSA_UNKNOWN;
1250 /* If we have an address literal, strip off the framing ready for turning it
1251 into a domain. The framing consists of matched square brackets possibly
1252 containing a keyword and a colon before the actual IP address. */
1254 if (domain[0] == '[')
1256 uschar *start = Ustrchr(domain, ':');
1257 if (start == NULL) start = domain;
1258 domain = string_copyn(start + 1, Ustrlen(start) - 2);
1261 /* Turn domains that look like bare IP addresses into domains in the reverse
1262 DNS. This code also deals with address literals and $sender_host_address. It's
1263 not quite kosher to treat bare domains such as EHLO 192.0.2.57 the same as
1264 address literals, but it's probably the most friendly thing to do. This is an
1265 extension to CSA, so we allow it to be turned off for proper conformance. */
1267 if (string_is_ip_address(domain, NULL) != 0)
1269 if (!dns_csa_use_reverse) return CSA_UNKNOWN;
1270 dns_build_reverse(domain, target);
1274 /* Find out if we've already done the CSA check for this domain. If we have,
1275 return the same result again. Otherwise build a new cached result structure
1276 for this domain. The name is filled in now, and the value is filled in when
1277 we return from this function. */
1279 t = tree_search(csa_cache, domain);
1280 if (t != NULL) return t->data.val;
1282 t = store_get_perm(sizeof(tree_node) + Ustrlen(domain));
1283 Ustrcpy(t->name, domain);
1284 (void)tree_insertnode(&csa_cache, t);
1286 /* Now we are ready to do the actual DNS lookup(s). */
1289 switch (dns_special_lookup(&dnsa, domain, T_CSA, &found))
1291 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1294 return t->data.val = CSA_DEFER_SRV;
1296 /* If we found nothing, the client's authorization is unknown. */
1300 return t->data.val = CSA_UNKNOWN;
1302 /* We got something! Go on to look at the reply in more detail. */
1308 /* Scan the reply for well-formed CSA SRV records. */
1310 for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS);
1312 rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT))
1314 if (rr->type != T_SRV) continue;
1316 /* Extract the numerical SRV fields (p is incremented) */
1319 GETSHORT(priority, p);
1320 GETSHORT(weight, p);
1324 debug_printf("CSA priority=%d weight=%d port=%d\n", priority, weight, port);
1326 /* Check the CSA version number */
1328 if (priority != 1) continue;
1330 /* If the domain does not have a CSA SRV record of its own (i.e. the domain
1331 found by dns_special_lookup() is a parent of the one we asked for), we check
1332 the subdomain assertions in the port field. At the moment there's only one
1333 assertion: legitimate SMTP clients are all explicitly authorized with CSA
1334 SRV records of their own. */
1336 if (found != domain)
1339 return t->data.val = CSA_FAIL_EXPLICIT;
1341 return t->data.val = CSA_UNKNOWN;
1344 /* This CSA SRV record refers directly to our domain, so we check the value
1345 in the weight field to work out the domain's authorization. 0 and 1 are
1346 unauthorized; 3 means the client is authorized but we can't check the IP
1347 address in order to authenticate it, so we treat it as unknown; values
1348 greater than 3 are undefined. */
1350 if (weight < 2) return t->data.val = CSA_FAIL_DOMAIN;
1352 if (weight > 2) continue;
1354 /* Weight == 2, which means the domain is authorized. We must check that the
1355 client's IP address is listed as one of the SRV target addresses. Save the
1356 target hostname then break to scan the additional data for its addresses. */
1358 (void)dn_expand(dnsa.answer, dnsa.answer + dnsa.answerlen, p,
1359 (DN_EXPAND_ARG4_TYPE)target, sizeof(target));
1361 DEBUG(D_acl) debug_printf("CSA target is %s\n", target);
1366 /* If we didn't break the loop then no appropriate records were found. */
1368 if (rr == NULL) return t->data.val = CSA_UNKNOWN;
1370 /* Do not check addresses if the target is ".", in accordance with RFC 2782.
1371 A target of "." indicates there are no valid addresses, so the client cannot
1372 be authorized. (This is an odd configuration because weight=2 target=. is
1373 equivalent to weight=1, but we check for it in order to keep load off the
1374 root name servers.) Note that dn_expand() turns "." into "". */
1376 if (Ustrcmp(target, "") == 0) return t->data.val = CSA_FAIL_NOADDR;
1378 /* Scan the additional section of the CSA SRV reply for addresses belonging
1379 to the target. If the name server didn't return any additional data (e.g.
1380 because it does not fully support SRV records), we need to do another lookup
1381 to obtain the target addresses; otherwise we have a definitive result. */
1383 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ADDITIONAL, target);
1384 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1386 /* The DNS lookup type corresponds to the IP version used by the client. */
1389 if (Ustrchr(sender_host_address, ':') != NULL)
1392 #endif /* HAVE_IPV6 */
1396 #if HAVE_IPV6 && defined(SUPPORT_A6)
1400 switch (dns_lookup(&dnsa, target, type, NULL))
1402 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1405 return t->data.val = CSA_DEFER_ADDR;
1407 /* If the query succeeded, scan the addresses and return the result. */
1410 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ANSWERS, target);
1411 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1412 /* else fall through */
1414 /* If the target has no IP addresses, the client cannot have an authorized
1415 IP address. However, if the target site uses A6 records (not AAAA records)
1416 we have to do yet another lookup in order to check them. */
1421 #if HAVE_IPV6 && defined(SUPPORT_A6)
1422 if (type == T_AAAA) { type = T_A6; goto DNS_LOOKUP_AGAIN; }
1425 return t->data.val = CSA_FAIL_NOADDR;
1431 /*************************************************
1432 * Handle verification (address & other) *
1433 *************************************************/
1435 /* This function implements the "verify" condition. It is called when
1436 encountered in any ACL, because some tests are almost always permitted. Some
1437 just don't make sense, and always fail (for example, an attempt to test a host
1438 lookup for a non-TCP/IP message). Others are restricted to certain ACLs.
1441 where where called from
1442 addr the recipient address that the ACL is handling, or NULL
1443 arg the argument of "verify"
1444 user_msgptr pointer for user message
1445 log_msgptr pointer for log message
1446 basic_errno where to put verify errno
1448 Returns: OK verification condition succeeded
1449 FAIL verification failed
1450 DEFER there was a problem verifying
1455 acl_verify(int where, address_item *addr, uschar *arg,
1456 uschar **user_msgptr, uschar **log_msgptr, int *basic_errno)
1460 int callout_overall = -1;
1461 int callout_connect = -1;
1462 int verify_options = 0;
1464 BOOL verify_header_sender = FALSE;
1465 BOOL defer_ok = FALSE;
1466 BOOL callout_defer_ok = FALSE;
1467 BOOL no_details = FALSE;
1468 BOOL success_on_redirect = FALSE;
1469 address_item *sender_vaddr = NULL;
1470 uschar *verify_sender_address = NULL;
1471 uschar *pm_mailfrom = NULL;
1472 uschar *se_mailfrom = NULL;
1474 /* Some of the verify items have slash-separated options; some do not. Diagnose
1475 an error if options are given for items that don't expect them. This code has
1476 now got very message. Refactoring to use a table would be a good idea one day.
1479 uschar *slash = Ustrchr(arg, '/');
1481 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
1483 if (ss == NULL) goto BAD_VERIFY;
1485 /* Handle name/address consistency verification in a separate function. */
1487 if (strcmpic(ss, US"reverse_host_lookup") == 0)
1489 if (slash != NULL) goto NO_OPTIONS;
1490 if (sender_host_address == NULL) return OK;
1491 return acl_verify_reverse(user_msgptr, log_msgptr);
1494 /* TLS certificate verification is done at STARTTLS time; here we just
1495 test whether it was successful or not. (This is for optional verification; for
1496 mandatory verification, the connection doesn't last this long.) */
1498 if (strcmpic(ss, US"certificate") == 0)
1500 if (slash != NULL) goto NO_OPTIONS;
1501 if (tls_certificate_verified) return OK;
1502 *user_msgptr = US"no verified certificate";
1506 /* We can test the result of optional HELO verification that might have
1507 occurred earlier. If not, we can attempt the verification now. */
1509 if (strcmpic(ss, US"helo") == 0)
1511 if (slash != NULL) goto NO_OPTIONS;
1512 if (!helo_verified && !helo_verify_failed) smtp_verify_helo();
1513 return helo_verified? OK : FAIL;
1516 /* Do Client SMTP Authorization checks in a separate function, and turn the
1517 result code into user-friendly strings. */
1519 if (strcmpic(ss, US"csa") == 0)
1521 rc = acl_verify_csa(list);
1522 *log_msgptr = *user_msgptr = string_sprintf("client SMTP authorization %s",
1523 csa_reason_string[rc]);
1524 csa_status = csa_status_string[rc];
1525 DEBUG(D_acl) debug_printf("CSA result %s\n", csa_status);
1526 return csa_return_code[rc];
1529 /* Check that all relevant header lines have the correct syntax. If there is
1530 a syntax error, we return details of the error to the sender if configured to
1531 send out full details. (But a "message" setting on the ACL can override, as
1534 if (strcmpic(ss, US"header_syntax") == 0)
1536 if (slash != NULL) goto NO_OPTIONS;
1537 if (where != ACL_WHERE_DATA && where != ACL_WHERE_NOTSMTP) goto WRONG_ACL;
1538 rc = verify_check_headers(log_msgptr);
1539 if (rc != OK && smtp_return_error_details && *log_msgptr != NULL)
1540 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1544 /* Check that no recipient of this message is "blind", that is, every envelope
1545 recipient must be mentioned in either To: or Cc:. */
1547 if (strcmpic(ss, US"not_blind") == 0)
1549 if (slash != NULL) goto NO_OPTIONS;
1550 if (where != ACL_WHERE_DATA && where != ACL_WHERE_NOTSMTP) goto WRONG_ACL;
1551 rc = verify_check_notblind();
1554 *log_msgptr = string_sprintf("bcc recipient detected");
1555 if (smtp_return_error_details)
1556 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1561 /* The remaining verification tests check recipient and sender addresses,
1562 either from the envelope or from the header. There are a number of
1563 slash-separated options that are common to all of them. */
1566 /* Check that there is at least one verifiable sender address in the relevant
1567 header lines. This can be followed by callout and defer options, just like
1568 sender and recipient. */
1570 if (strcmpic(ss, US"header_sender") == 0)
1572 if (where != ACL_WHERE_DATA && where != ACL_WHERE_NOTSMTP) goto WRONG_ACL;
1573 verify_header_sender = TRUE;
1576 /* Otherwise, first item in verify argument must be "sender" or "recipient".
1577 In the case of a sender, this can optionally be followed by an address to use
1578 in place of the actual sender (rare special-case requirement). */
1580 else if (strncmpic(ss, US"sender", 6) == 0)
1583 if (where > ACL_WHERE_NOTSMTP)
1585 *log_msgptr = string_sprintf("cannot verify sender in ACL for %s "
1586 "(only possible for MAIL, RCPT, PREDATA, or DATA)",
1587 acl_wherenames[where]);
1591 verify_sender_address = sender_address;
1594 while (isspace(*s)) s++;
1595 if (*s++ != '=') goto BAD_VERIFY;
1596 while (isspace(*s)) s++;
1597 verify_sender_address = string_copy(s);
1602 if (strcmpic(ss, US"recipient") != 0) goto BAD_VERIFY;
1605 *log_msgptr = string_sprintf("cannot verify recipient in ACL for %s "
1606 "(only possible for RCPT)", acl_wherenames[where]);
1611 /* Remaining items are optional; they apply to sender and recipient
1612 verification, including "header sender" verification. */
1614 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size))
1617 if (strcmpic(ss, US"defer_ok") == 0) defer_ok = TRUE;
1618 else if (strcmpic(ss, US"no_details") == 0) no_details = TRUE;
1619 else if (strcmpic(ss, US"success_on_redirect") == 0) success_on_redirect = TRUE;
1621 /* These two old options are left for backwards compatibility */
1623 else if (strcmpic(ss, US"callout_defer_ok") == 0)
1625 callout_defer_ok = TRUE;
1626 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1629 else if (strcmpic(ss, US"check_postmaster") == 0)
1632 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1635 /* The callout option has a number of sub-options, comma separated */
1637 else if (strncmpic(ss, US"callout", 7) == 0)
1639 callout = CALLOUT_TIMEOUT_DEFAULT;
1643 while (isspace(*ss)) ss++;
1649 while (isspace(*ss)) ss++;
1651 /* This callout option handling code has become a mess as new options
1652 have been added in an ad hoc manner. It should be tidied up into some
1653 kind of table-driven thing. */
1655 while ((opt = string_nextinlist(&ss, &optsep, buffer, sizeof(buffer)))
1658 if (strcmpic(opt, US"defer_ok") == 0) callout_defer_ok = TRUE;
1659 else if (strcmpic(opt, US"no_cache") == 0)
1660 verify_options |= vopt_callout_no_cache;
1661 else if (strcmpic(opt, US"random") == 0)
1662 verify_options |= vopt_callout_random;
1663 else if (strcmpic(opt, US"use_sender") == 0)
1664 verify_options |= vopt_callout_recipsender;
1665 else if (strcmpic(opt, US"use_postmaster") == 0)
1666 verify_options |= vopt_callout_recippmaster;
1667 else if (strcmpic(opt, US"postmaster") == 0) pm_mailfrom = US"";
1668 else if (strcmpic(opt, US"fullpostmaster") == 0)
1671 verify_options |= vopt_callout_fullpm;
1674 else if (strncmpic(opt, US"mailfrom", 8) == 0)
1676 if (!verify_header_sender)
1678 *log_msgptr = string_sprintf("\"mailfrom\" is allowed as a "
1679 "callout option only for verify=header_sender (detected in ACL "
1680 "condition \"%s\")", arg);
1684 while (isspace(*opt)) opt++;
1687 *log_msgptr = string_sprintf("'=' expected after "
1688 "\"mailfrom\" in ACL condition \"%s\"", arg);
1691 while (isspace(*opt)) opt++;
1692 se_mailfrom = string_copy(opt);
1695 else if (strncmpic(opt, US"postmaster_mailfrom", 19) == 0)
1698 while (isspace(*opt)) opt++;
1701 *log_msgptr = string_sprintf("'=' expected after "
1702 "\"postmaster_mailfrom\" in ACL condition \"%s\"", arg);
1705 while (isspace(*opt)) opt++;
1706 pm_mailfrom = string_copy(opt);
1709 else if (strncmpic(opt, US"maxwait", 7) == 0)
1712 while (isspace(*opt)) opt++;
1715 *log_msgptr = string_sprintf("'=' expected after \"maxwait\" in "
1716 "ACL condition \"%s\"", arg);
1719 while (isspace(*opt)) opt++;
1720 callout_overall = readconf_readtime(opt, 0, FALSE);
1721 if (callout_overall < 0)
1723 *log_msgptr = string_sprintf("bad time value in ACL condition "
1724 "\"verify %s\"", arg);
1728 else if (strncmpic(opt, US"connect", 7) == 0)
1731 while (isspace(*opt)) opt++;
1734 *log_msgptr = string_sprintf("'=' expected after "
1735 "\"callout_overaall\" in ACL condition \"%s\"", arg);
1738 while (isspace(*opt)) opt++;
1739 callout_connect = readconf_readtime(opt, 0, FALSE);
1740 if (callout_connect < 0)
1742 *log_msgptr = string_sprintf("bad time value in ACL condition "
1743 "\"verify %s\"", arg);
1747 else /* Plain time is callout connect/command timeout */
1749 callout = readconf_readtime(opt, 0, FALSE);
1752 *log_msgptr = string_sprintf("bad time value in ACL condition "
1753 "\"verify %s\"", arg);
1761 *log_msgptr = string_sprintf("'=' expected after \"callout\" in "
1762 "ACL condition \"%s\"", arg);
1768 /* Option not recognized */
1772 *log_msgptr = string_sprintf("unknown option \"%s\" in ACL "
1773 "condition \"verify %s\"", ss, arg);
1778 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster)) ==
1779 (vopt_callout_recipsender|vopt_callout_recippmaster))
1781 *log_msgptr = US"only one of use_sender and use_postmaster can be set "
1782 "for a recipient callout";
1786 /* Handle sender-in-header verification. Default the user message to the log
1787 message if giving out verification details. */
1789 if (verify_header_sender)
1792 rc = verify_check_header_address(user_msgptr, log_msgptr, callout,
1793 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, verify_options,
1797 *basic_errno = verrno;
1798 if (smtp_return_error_details)
1800 if (*user_msgptr == NULL && *log_msgptr != NULL)
1801 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1802 if (rc == DEFER) acl_temp_details = TRUE;
1807 /* Handle a sender address. The default is to verify *the* sender address, but
1808 optionally a different address can be given, for special requirements. If the
1809 address is empty, we are dealing with a bounce message that has no sender, so
1810 we cannot do any checking. If the real sender address gets rewritten during
1811 verification (e.g. DNS widening), set the flag to stop it being rewritten again
1812 during message reception.
1814 A list of verified "sender" addresses is kept to try to avoid doing to much
1815 work repetitively when there are multiple recipients in a message and they all
1816 require sender verification. However, when callouts are involved, it gets too
1817 complicated because different recipients may require different callout options.
1818 Therefore, we always do a full sender verify when any kind of callout is
1819 specified. Caching elsewhere, for instance in the DNS resolver and in the
1820 callout handling, should ensure that this is not terribly inefficient. */
1822 else if (verify_sender_address != NULL)
1824 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster))
1827 *log_msgptr = US"use_sender or use_postmaster cannot be used for a "
1828 "sender verify callout";
1832 sender_vaddr = verify_checked_sender(verify_sender_address);
1833 if (sender_vaddr != NULL && /* Previously checked */
1834 callout <= 0) /* No callout needed this time */
1836 /* If the "routed" flag is set, it means that routing worked before, so
1837 this check can give OK (the saved return code value, if set, belongs to a
1838 callout that was done previously). If the "routed" flag is not set, routing
1839 must have failed, so we use the saved return code. */
1841 if (testflag(sender_vaddr, af_verify_routed)) rc = OK; else
1843 rc = sender_vaddr->special_action;
1844 *basic_errno = sender_vaddr->basic_errno;
1846 HDEBUG(D_acl) debug_printf("using cached sender verify result\n");
1849 /* Do a new verification, and cache the result. The cache is used to avoid
1850 verifying the sender multiple times for multiple RCPTs when callouts are not
1851 specified (see comments above).
1853 The cache is also used on failure to give details in response to the first
1854 RCPT that gets bounced for this reason. However, this can be suppressed by
1855 the no_details option, which sets the flag that says "this detail has already
1856 been sent". The cache normally contains just one address, but there may be
1857 more in esoteric circumstances. */
1862 uschar *save_address_data = deliver_address_data;
1864 sender_vaddr = deliver_make_addr(verify_sender_address, TRUE);
1865 if (no_details) setflag(sender_vaddr, af_sverify_told);
1866 if (verify_sender_address[0] != 0)
1868 /* If this is the real sender address, save the unrewritten version
1869 for use later in receive. Otherwise, set a flag so that rewriting the
1870 sender in verify_address() does not update sender_address. */
1872 if (verify_sender_address == sender_address)
1873 sender_address_unrewritten = sender_address;
1875 verify_options |= vopt_fake_sender;
1877 if (success_on_redirect)
1878 verify_options |= vopt_success_on_redirect;
1880 /* The recipient, qualify, and expn options are never set in
1883 rc = verify_address(sender_vaddr, NULL, verify_options, callout,
1884 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, &routed);
1886 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
1890 if (Ustrcmp(sender_vaddr->address, verify_sender_address) != 0)
1892 DEBUG(D_acl) debug_printf("sender %s verified ok as %s\n",
1893 verify_sender_address, sender_vaddr->address);
1897 DEBUG(D_acl) debug_printf("sender %s verified ok\n",
1898 verify_sender_address);
1901 else *basic_errno = sender_vaddr->basic_errno;
1903 else rc = OK; /* Null sender */
1905 /* Cache the result code */
1907 if (routed) setflag(sender_vaddr, af_verify_routed);
1908 if (callout > 0) setflag(sender_vaddr, af_verify_callout);
1909 sender_vaddr->special_action = rc;
1910 sender_vaddr->next = sender_verified_list;
1911 sender_verified_list = sender_vaddr;
1913 /* Restore the recipient address data, which might have been clobbered by
1914 the sender verification. */
1916 deliver_address_data = save_address_data;
1919 /* Put the sender address_data value into $sender_address_data */
1921 sender_address_data = sender_vaddr->p.address_data;
1924 /* A recipient address just gets a straightforward verify; again we must handle
1925 the DEFER overrides. */
1931 if (success_on_redirect)
1932 verify_options |= vopt_success_on_redirect;
1934 /* We must use a copy of the address for verification, because it might
1938 rc = verify_address(&addr2, NULL, verify_options|vopt_is_recipient, callout,
1939 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, NULL);
1940 HDEBUG(D_acl) debug_printf("----------- end verify ------------\n");
1942 *log_msgptr = addr2.message;
1943 *user_msgptr = (addr2.user_message != NULL)?
1944 addr2.user_message : addr2.message;
1945 *basic_errno = addr2.basic_errno;
1947 /* Make $address_data visible */
1948 deliver_address_data = addr2.p.address_data;
1951 /* We have a result from the relevant test. Handle defer overrides first. */
1953 if (rc == DEFER && (defer_ok ||
1954 (callout_defer_ok && *basic_errno == ERRNO_CALLOUTDEFER)))
1956 HDEBUG(D_acl) debug_printf("verify defer overridden by %s\n",
1957 defer_ok? "defer_ok" : "callout_defer_ok");
1961 /* If we've failed a sender, set up a recipient message, and point
1962 sender_verified_failed to the address item that actually failed. */
1964 if (rc != OK && verify_sender_address != NULL)
1968 *log_msgptr = *user_msgptr = US"Sender verify failed";
1970 else if (*basic_errno != ERRNO_CALLOUTDEFER)
1972 *log_msgptr = *user_msgptr = US"Could not complete sender verify";
1976 *log_msgptr = US"Could not complete sender verify callout";
1977 *user_msgptr = smtp_return_error_details? sender_vaddr->user_message :
1981 sender_verified_failed = sender_vaddr;
1984 /* Verifying an address messes up the values of $domain and $local_part,
1985 so reset them before returning if this is a RCPT ACL. */
1989 deliver_domain = addr->domain;
1990 deliver_localpart = addr->local_part;
1994 /* Syntax errors in the verify argument come here. */
1997 *log_msgptr = string_sprintf("expected \"sender[=address]\", \"recipient\", "
1998 "\"helo\", \"header_syntax\", \"header_sender\" or "
1999 "\"reverse_host_lookup\" at start of ACL condition "
2000 "\"verify %s\"", arg);
2003 /* Options supplied when not allowed come here */
2006 *log_msgptr = string_sprintf("unexpected '/' found in \"%s\" "
2007 "(this verify item has no options)", arg);
2010 /* Calls in the wrong ACL come here */
2013 *log_msgptr = string_sprintf("cannot check header contents in ACL for %s "
2014 "(only possible in ACL for DATA)", acl_wherenames[where]);
2021 /*************************************************
2022 * Check argument for control= modifier *
2023 *************************************************/
2025 /* Called from acl_check_condition() below
2028 arg the argument string for control=
2029 pptr set to point to the terminating character
2030 where which ACL we are in
2031 log_msgptr for error messages
2033 Returns: CONTROL_xxx value
2037 decode_control(uschar *arg, uschar **pptr, int where, uschar **log_msgptr)
2042 for (d = controls_list;
2043 d < controls_list + sizeof(controls_list)/sizeof(control_def);
2046 len = Ustrlen(d->name);
2047 if (Ustrncmp(d->name, arg, len) == 0) break;
2050 if (d >= controls_list + sizeof(controls_list)/sizeof(control_def) ||
2051 (arg[len] != 0 && (!d->has_option || arg[len] != '/')))
2053 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
2054 return CONTROL_ERROR;
2063 /*************************************************
2064 * Handle rate limiting *
2065 *************************************************/
2067 /* Called by acl_check_condition() below to calculate the result
2068 of the ACL ratelimit condition.
2070 Note that the return value might be slightly unexpected: if the
2071 sender's rate is above the limit then the result is OK. This is
2072 similar to the dnslists condition, and is so that you can write
2073 ACL clauses like: defer ratelimit = 15 / 1h
2076 arg the option string for ratelimit=
2077 where ACL_WHERE_xxxx indicating which ACL this is
2078 log_msgptr for error messages
2080 Returns: OK - Sender's rate is above limit
2081 FAIL - Sender's rate is below limit
2082 DEFER - Problem opening ratelimit database
2083 ERROR - Syntax error in options.
2087 acl_ratelimit(uschar *arg, int where, uschar **log_msgptr)
2089 double limit, period;
2092 BOOL have_key = FALSE, leaky = FALSE, strict = FALSE;
2093 BOOL per_byte = FALSE, per_cmd = FALSE, per_conn = FALSE, per_mail = FALSE;
2095 tree_node **anchor, *t;
2096 open_db dbblock, *dbm;
2097 dbdata_ratelimit *dbd;
2100 /* Parse the first two options and record their values in expansion
2101 variables. These variables allow the configuration to have informative
2102 error messages based on rate limits obtained from a table lookup. */
2104 /* First is the maximum number of messages per period and maximum burst
2105 size, which must be greater than or equal to zero. Zero is useful for
2106 rate measurement as opposed to rate limiting. */
2108 sender_rate_limit = string_nextinlist(&arg, &sep, NULL, 0);
2109 if (sender_rate_limit == NULL)
2113 limit = Ustrtod(sender_rate_limit, &ss);
2114 if (tolower(*ss) == 'k') { limit *= 1024.0; ss++; }
2115 else if (tolower(*ss) == 'm') { limit *= 1024.0*1024.0; ss++; }
2116 else if (tolower(*ss) == 'g') { limit *= 1024.0*1024.0*1024.0; ss++; }
2118 if (limit < 0.0 || *ss != 0)
2120 *log_msgptr = string_sprintf("syntax error in argument for "
2121 "\"ratelimit\" condition: \"%s\" is not a positive number",
2126 /* We use the rest of the argument list following the limit as the
2127 lookup key, because it doesn't make sense to use the same stored data
2128 if the period or options are different. */
2132 /* Second is the rate measurement period and exponential smoothing time
2133 constant. This must be strictly greater than zero, because zero leads to
2134 run-time division errors. */
2136 sender_rate_period = string_nextinlist(&arg, &sep, NULL, 0);
2137 if (sender_rate_period == NULL) period = -1.0;
2138 else period = readconf_readtime(sender_rate_period, 0, FALSE);
2141 *log_msgptr = string_sprintf("syntax error in argument for "
2142 "\"ratelimit\" condition: \"%s\" is not a time value",
2143 sender_rate_period);
2147 /* Parse the other options. Should we check if the per_* options are being
2148 used in ACLs where they don't make sense, e.g. per_mail in the connect ACL? */
2150 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2153 if (strcmpic(ss, US"leaky") == 0) leaky = TRUE;
2154 else if (strcmpic(ss, US"strict") == 0) strict = TRUE;
2155 else if (strcmpic(ss, US"per_byte") == 0) per_byte = TRUE;
2156 else if (strcmpic(ss, US"per_cmd") == 0) per_cmd = TRUE;
2157 else if (strcmpic(ss, US"per_conn") == 0) per_conn = TRUE;
2158 else if (strcmpic(ss, US"per_mail") == 0) per_mail = TRUE;
2159 else if (strcmpic(ss, US"per_rcpt") == 0) per_cmd = TRUE; /* alias */
2160 else have_key = TRUE;
2162 if (leaky + strict > 1 || per_byte + per_cmd + per_conn + per_mail > 1)
2164 *log_msgptr = US"conflicting options for \"ratelimit\" condition";
2168 /* Default option values */
2169 if (!strict) leaky = TRUE;
2170 if (!per_byte && !per_cmd && !per_conn) per_mail = TRUE;
2172 /* If there is no explicit key, use the sender_host_address. If there is no
2173 sender_host_address (e.g. -bs or acl_not_smtp) then we simply omit it. */
2175 if (!have_key && sender_host_address != NULL)
2176 key = string_sprintf("%s / %s", key, sender_host_address);
2178 HDEBUG(D_acl) debug_printf("ratelimit condition limit=%.0f period=%.0f key=%s\n",
2179 limit, period, key);
2181 /* See if we have already computed the rate by looking in the relevant tree. For
2182 per-connection rate limiting, store tree nodes and dbdata in the permanent pool
2183 so that they survive across resets. */
2186 old_pool = store_pool;
2190 anchor = &ratelimiters_conn;
2191 store_pool = POOL_PERM;
2193 else if (per_mail || per_byte)
2194 anchor = &ratelimiters_mail;
2196 anchor = &ratelimiters_cmd;
2198 if (anchor != NULL && (t = tree_search(*anchor, key)) != NULL)
2201 /* The following few lines duplicate some of the code below. */
2202 if (dbd->rate < limit) rc = FAIL;
2204 store_pool = old_pool;
2205 sender_rate = string_sprintf("%.1f", dbd->rate);
2207 debug_printf("ratelimit found pre-computed rate %s\n", sender_rate);
2211 /* We aren't using a pre-computed rate, so get a previously recorded
2212 rate from the database, update it, and write it back. If there's no
2213 previous rate for this key, create one. */
2215 dbm = dbfn_open(US"ratelimit", O_RDWR, &dbblock, TRUE);
2218 store_pool = old_pool;
2220 HDEBUG(D_acl) debug_printf("ratelimit database not available\n");
2221 *log_msgptr = US"ratelimit database not available";
2224 dbd = dbfn_read(dbm, key);
2226 gettimeofday(&tv, NULL);
2230 HDEBUG(D_acl) debug_printf("ratelimit initializing new key's data\n");
2231 dbd = store_get(sizeof(dbdata_ratelimit));
2232 dbd->time_stamp = tv.tv_sec;
2233 dbd->time_usec = tv.tv_usec;
2238 /* The smoothed rate is computed using an exponentially weighted moving
2239 average adjusted for variable sampling intervals. The standard EWMA for
2240 a fixed sampling interval is: f'(t) = (1 - a) * f(t) + a * f'(t - 1)
2241 where f() is the measured value and f'() is the smoothed value.
2243 Old data decays out of the smoothed value exponentially, such that data n
2244 samples old is multiplied by a^n. The exponential decay time constant p
2245 is defined such that data p samples old is multiplied by 1/e, which means
2246 that a = exp(-1/p). We can maintain the same time constant for a variable
2247 sampling interval i by using a = exp(-i/p).
2249 The rate we are measuring is messages per period, suitable for directly
2250 comparing with the limit. The average rate between now and the previous
2251 message is period / interval, which we feed into the EWMA as the sample.
2253 It turns out that the number of messages required for the smoothed rate
2254 to reach the limit when they are sent in a burst is equal to the limit.
2255 This can be seen by analysing the value of the smoothed rate after N
2256 messages sent at even intervals. Let k = (1 - a) * p/i
2258 rate_1 = (1 - a) * p/i + a * rate_0
2260 rate_2 = k + a * rate_1
2261 = k + a * k + a^2 * rate_0
2262 rate_3 = k + a * k + a^2 * k + a^3 * rate_0
2263 rate_N = rate_0 * a^N + k * SUM(x=0..N-1)(a^x)
2264 = rate_0 * a^N + k * (1 - a^N) / (1 - a)
2265 = rate_0 * a^N + p/i * (1 - a^N)
2267 When N is large, a^N -> 0 so rate_N -> p/i as desired.
2269 rate_N = p/i + (rate_0 - p/i) * a^N
2270 a^N = (rate_N - p/i) / (rate_0 - p/i)
2271 N * -i/p = log((rate_N - p/i) / (rate_0 - p/i))
2272 N = p/i * log((rate_0 - p/i) / (rate_N - p/i))
2274 Numerical analysis of the above equation, setting the computed rate to
2275 increase from rate_0 = 0 to rate_N = limit, shows that for large sending
2276 rates, p/i, the number of messages N = limit. So limit serves as both the
2277 maximum rate measured in messages per period, and the maximum number of
2278 messages that can be sent in a fast burst. */
2280 double this_time = (double)tv.tv_sec
2281 + (double)tv.tv_usec / 1000000.0;
2282 double prev_time = (double)dbd->time_stamp
2283 + (double)dbd->time_usec / 1000000.0;
2285 /* We must avoid division by zero, and deal gracefully with the clock going
2286 backwards. If we blunder ahead when time is in reverse then the computed
2287 rate will be bogus. To be safe we clamp interval to a very small number. */
2289 double interval = this_time - prev_time <= 0.0 ? 1e-9
2290 : this_time - prev_time;
2292 double i_over_p = interval / period;
2293 double a = exp(-i_over_p);
2295 dbd->time_stamp = tv.tv_sec;
2296 dbd->time_usec = tv.tv_usec;
2298 /* If we are measuring the rate in bytes per period, multiply the
2299 measured rate by the message size. If we don't know the message size
2300 then it's safe to just use a value of zero and let the recorded rate
2301 decay as if nothing happened. */
2304 dbd->rate = (message_size < 0 ? 0.0 : (double)message_size)
2305 * (1 - a) / i_over_p + a * dbd->rate;
2306 else if (per_cmd && where == ACL_WHERE_NOTSMTP)
2307 dbd->rate = (double)recipients_count
2308 * (1 - a) / i_over_p + a * dbd->rate;
2310 dbd->rate = (1 - a) / i_over_p + a * dbd->rate;
2313 /* Clients sending at the limit are considered to be over the limit. This
2314 matters for edge cases such the first message sent by a client (which gets
2315 the initial rate of 0.0) when the rate limit is zero (i.e. the client should
2316 be completely blocked). */
2318 if (dbd->rate < limit) rc = FAIL;
2321 /* Update the state if the rate is low or if we are being strict. If we
2322 are in leaky mode and the sender's rate is too high, we do not update
2323 the recorded rate in order to avoid an over-aggressive sender's retry
2324 rate preventing them from getting any email through. */
2326 if (rc == FAIL || !leaky)
2327 dbfn_write(dbm, key, dbd, sizeof(dbdata_ratelimit));
2330 /* Store the result in the tree for future reference, if necessary. */
2334 t = store_get(sizeof(tree_node) + Ustrlen(key));
2336 Ustrcpy(t->name, key);
2337 (void)tree_insertnode(anchor, t);
2340 /* We create the formatted version of the sender's rate very late in
2341 order to ensure that it is done using the correct storage pool. */
2343 store_pool = old_pool;
2344 sender_rate = string_sprintf("%.1f", dbd->rate);
2347 debug_printf("ratelimit computed rate %s\n", sender_rate);
2354 /*************************************************
2355 * Handle conditions/modifiers on an ACL item *
2356 *************************************************/
2358 /* Called from acl_check() below.
2362 cb ACL condition block - if NULL, result is OK
2363 where where called from
2364 addr the address being checked for RCPT, or NULL
2365 level the nesting level
2366 epp pointer to pass back TRUE if "endpass" encountered
2367 (applies only to "accept" and "discard")
2368 user_msgptr user message pointer
2369 log_msgptr log message pointer
2370 basic_errno pointer to where to put verify error
2372 Returns: OK - all conditions are met
2373 DISCARD - an "acl" condition returned DISCARD - only allowed
2374 for "accept" or "discard" verbs
2375 FAIL - at least one condition fails
2376 FAIL_DROP - an "acl" condition returned FAIL_DROP
2377 DEFER - can't tell at the moment (typically, lookup defer,
2378 but can be temporary callout problem)
2379 ERROR - ERROR from nested ACL or expansion failure or other
2384 acl_check_condition(int verb, acl_condition_block *cb, int where,
2385 address_item *addr, int level, BOOL *epp, uschar **user_msgptr,
2386 uschar **log_msgptr, int *basic_errno)
2388 uschar *user_message = NULL;
2389 uschar *log_message = NULL;
2392 #ifdef WITH_CONTENT_SCAN
2396 for (; cb != NULL; cb = cb->next)
2401 /* The message and log_message items set up messages to be used in
2402 case of rejection. They are expanded later. */
2404 if (cb->type == ACLC_MESSAGE)
2406 user_message = cb->arg;
2410 if (cb->type == ACLC_LOG_MESSAGE)
2412 log_message = cb->arg;
2416 /* The endpass "condition" just sets a flag to show it occurred. This is
2417 checked at compile time to be on an "accept" or "discard" item. */
2419 if (cb->type == ACLC_ENDPASS)
2425 /* For other conditions and modifiers, the argument is expanded now for some
2426 of them, but not for all, because expansion happens down in some lower level
2427 checking functions in some cases. */
2429 if (cond_expand_at_top[cb->type])
2431 arg = expand_string(cb->arg);
2434 if (expand_string_forcedfail) continue;
2435 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s",
2436 cb->arg, expand_string_message);
2437 return search_find_defer? DEFER : ERROR;
2442 /* Show condition, and expanded condition if it's different */
2447 debug_printf("check %s%s %n",
2448 (!cond_modifiers[cb->type] && cb->u.negated)? "!":"",
2449 conditions[cb->type], &lhswidth);
2451 if (cb->type == ACLC_SET)
2453 debug_printf("acl_%s ", cb->u.varname);
2454 lhswidth += 5 + Ustrlen(cb->u.varname);
2457 debug_printf("= %s\n", cb->arg);
2460 debug_printf("%.*s= %s\n", lhswidth,
2464 /* Check that this condition makes sense at this time */
2466 if ((cond_forbids[cb->type] & (1 << where)) != 0)
2468 *log_msgptr = string_sprintf("cannot %s %s condition in %s ACL",
2469 cond_modifiers[cb->type]? "use" : "test",
2470 conditions[cb->type], acl_wherenames[where]);
2474 /* Run the appropriate test for each condition, or take the appropriate
2475 action for the remaining modifiers. */
2479 case ACLC_ADD_HEADER:
2483 /* A nested ACL that returns "discard" makes sense only for an "accept" or
2487 rc = acl_check_internal(where, addr, arg, level+1, user_msgptr, log_msgptr);
2488 if (rc == DISCARD && verb != ACL_ACCEPT && verb != ACL_DISCARD)
2490 *log_msgptr = string_sprintf("nested ACL returned \"discard\" for "
2491 "\"%s\" command (only allowed with \"accept\" or \"discard\")",
2497 case ACLC_AUTHENTICATED:
2498 rc = (sender_host_authenticated == NULL)? FAIL :
2499 match_isinlist(sender_host_authenticated, &arg, 0, NULL, NULL, MCL_STRING,
2503 #ifdef EXPERIMENTAL_BRIGHTMAIL
2504 case ACLC_BMI_OPTIN:
2506 int old_pool = store_pool;
2507 store_pool = POOL_PERM;
2508 bmi_current_optin = string_copy(arg);
2509 store_pool = old_pool;
2514 case ACLC_CONDITION:
2515 if (Ustrspn(arg, "0123456789") == Ustrlen(arg)) /* Digits, or empty */
2516 rc = (Uatoi(arg) == 0)? FAIL : OK;
2518 rc = (strcmpic(arg, US"no") == 0 ||
2519 strcmpic(arg, US"false") == 0)? FAIL :
2520 (strcmpic(arg, US"yes") == 0 ||
2521 strcmpic(arg, US"true") == 0)? OK : DEFER;
2523 *log_msgptr = string_sprintf("invalid \"condition\" value \"%s\"", arg);
2527 control_type = decode_control(arg, &p, where, log_msgptr);
2529 /* Check if this control makes sense at this time */
2531 if ((control_forbids[control_type] & (1 << where)) != 0)
2533 *log_msgptr = string_sprintf("cannot use \"control=%s\" in %s ACL",
2534 controls[control_type], acl_wherenames[where]);
2538 switch(control_type)
2540 case CONTROL_AUTH_UNADVERTISED:
2541 allow_auth_unadvertised = TRUE;
2544 #ifdef EXPERIMENTAL_BRIGHTMAIL
2545 case CONTROL_BMI_RUN:
2550 #ifdef EXPERIMENTAL_DOMAINKEYS
2551 case CONTROL_DK_VERIFY:
2559 case CONTROL_CASEFUL_LOCAL_PART:
2560 deliver_localpart = addr->cc_local_part;
2563 case CONTROL_CASELOWER_LOCAL_PART:
2564 deliver_localpart = addr->lc_local_part;
2567 case CONTROL_ENFORCE_SYNC:
2568 smtp_enforce_sync = TRUE;
2571 case CONTROL_NO_ENFORCE_SYNC:
2572 smtp_enforce_sync = FALSE;
2575 #ifdef WITH_CONTENT_SCAN
2576 case CONTROL_NO_MBOX_UNSPOOL:
2577 no_mbox_unspool = TRUE;
2581 case CONTROL_NO_MULTILINE:
2582 no_multiline_responses = TRUE;
2585 case CONTROL_FAKEDEFER:
2586 case CONTROL_FAKEREJECT:
2587 fake_response = (control_type == CONTROL_FAKEDEFER) ? DEFER : FAIL;
2591 while (*pp != 0) pp++;
2592 fake_response_text = expand_string(string_copyn(p+1, pp-p-1));
2597 /* Explicitly reset to default string */
2598 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).";
2602 case CONTROL_FREEZE:
2603 deliver_freeze = TRUE;
2604 deliver_frozen_at = time(NULL);
2605 freeze_tell = freeze_tell_config; /* Reset to configured value */
2606 if (Ustrncmp(p, "/no_tell", 8) == 0)
2613 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
2618 case CONTROL_QUEUE_ONLY:
2619 queue_only_policy = TRUE;
2622 case CONTROL_SUBMISSION:
2623 originator_name = US"";
2624 submission_mode = TRUE;
2627 if (Ustrncmp(p, "/sender_retain", 14) == 0)
2630 active_local_sender_retain = TRUE;
2631 active_local_from_check = FALSE;
2633 else if (Ustrncmp(p, "/domain=", 8) == 0)
2636 while (*pp != 0 && *pp != '/') pp++;
2637 submission_domain = string_copyn(p+8, pp-p-8);
2640 /* The name= option must be last, because it swallows the rest of
2642 else if (Ustrncmp(p, "/name=", 6) == 0)
2645 while (*pp != 0) pp++;
2646 submission_name = string_copy(parse_fix_phrase(p+6, pp-p-6,
2647 big_buffer, big_buffer_size));
2654 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
2659 case CONTROL_SUPPRESS_LOCAL_FIXUPS:
2660 suppress_local_fixups = TRUE;
2665 #ifdef WITH_CONTENT_SCAN
2667 rc = mime_decode(&arg);
2673 int delay = readconf_readtime(arg, 0, FALSE);
2676 *log_msgptr = string_sprintf("syntax error in argument for \"delay\" "
2677 "modifier: \"%s\" is not a time value", arg);
2682 HDEBUG(D_acl) debug_printf("delay modifier requests %d-second delay\n",
2687 debug_printf("delay skipped in -bh checking mode\n");
2690 /* It appears to be impossible to detect that a TCP/IP connection has
2691 gone away without reading from it. This means that we cannot shorten
2692 the delay below if the client goes away, because we cannot discover
2693 that the client has closed its end of the connection. (The connection
2694 is actually in a half-closed state, waiting for the server to close its
2695 end.) It would be nice to be able to detect this state, so that the
2696 Exim process is not held up unnecessarily. However, it seems that we
2697 can't. The poll() function does not do the right thing, and in any case
2698 it is not always available.
2700 NOTE: If ever this state of affairs changes, remember that we may be
2701 dealing with stdin/stdout here, in addition to TCP/IP connections.
2702 Whatever is done must work in both cases. To detected the stdin/stdout
2703 case, check for smtp_in or smtp_out being NULL. */
2707 while (delay > 0) delay = sleep(delay);
2713 #ifdef WITH_OLD_DEMIME
2719 #ifdef EXPERIMENTAL_DOMAINKEYS
2720 case ACLC_DK_DOMAIN_SOURCE:
2721 if (dk_verify_block == NULL) { rc = FAIL; break; };
2722 /* check header source of domain against given string */
2723 switch (dk_verify_block->address_source) {
2724 case DK_EXIM_ADDRESS_FROM_FROM:
2725 rc = match_isinlist(US"from", &arg, 0, NULL,
2726 NULL, MCL_STRING, TRUE, NULL);
2728 case DK_EXIM_ADDRESS_FROM_SENDER:
2729 rc = match_isinlist(US"sender", &arg, 0, NULL,
2730 NULL, MCL_STRING, TRUE, NULL);
2732 case DK_EXIM_ADDRESS_NONE:
2733 rc = match_isinlist(US"none", &arg, 0, NULL,
2734 NULL, MCL_STRING, TRUE, NULL);
2739 case ACLC_DK_POLICY:
2740 if (dk_verify_block == NULL) { rc = FAIL; break; };
2741 /* check policy against given string, default FAIL */
2743 if (dk_verify_block->signsall)
2744 rc = match_isinlist(US"signsall", &arg, 0, NULL,
2745 NULL, MCL_STRING, TRUE, NULL);
2746 if (dk_verify_block->testing)
2747 rc = match_isinlist(US"testing", &arg, 0, NULL,
2748 NULL, MCL_STRING, TRUE, NULL);
2751 case ACLC_DK_SENDER_DOMAINS:
2752 if (dk_verify_block == NULL) { rc = FAIL; break; };
2753 if (dk_verify_block->domain != NULL)
2754 rc = match_isinlist(dk_verify_block->domain, &arg, 0, &domainlist_anchor,
2755 NULL, MCL_DOMAIN, TRUE, NULL);
2759 case ACLC_DK_SENDER_LOCAL_PARTS:
2760 if (dk_verify_block == NULL) { rc = FAIL; break; };
2761 if (dk_verify_block->local_part != NULL)
2762 rc = match_isinlist(dk_verify_block->local_part, &arg, 0, &localpartlist_anchor,
2763 NULL, MCL_LOCALPART, TRUE, NULL);
2767 case ACLC_DK_SENDERS:
2768 if (dk_verify_block == NULL) { rc = FAIL; break; };
2769 if (dk_verify_block->address != NULL)
2770 rc = match_address_list(dk_verify_block->address, TRUE, TRUE, &arg, NULL, -1, 0, NULL);
2774 case ACLC_DK_STATUS:
2775 if (dk_verify_block == NULL) { rc = FAIL; break; };
2776 if (dk_verify_block->result > 0) {
2777 switch(dk_verify_block->result) {
2778 case DK_EXIM_RESULT_BAD_FORMAT:
2779 rc = match_isinlist(US"bad format", &arg, 0, NULL,
2780 NULL, MCL_STRING, TRUE, NULL);
2782 case DK_EXIM_RESULT_NO_KEY:
2783 rc = match_isinlist(US"no key", &arg, 0, NULL,
2784 NULL, MCL_STRING, TRUE, NULL);
2786 case DK_EXIM_RESULT_NO_SIGNATURE:
2787 rc = match_isinlist(US"no signature", &arg, 0, NULL,
2788 NULL, MCL_STRING, TRUE, NULL);
2790 case DK_EXIM_RESULT_REVOKED:
2791 rc = match_isinlist(US"revoked", &arg, 0, NULL,
2792 NULL, MCL_STRING, TRUE, NULL);
2794 case DK_EXIM_RESULT_NON_PARTICIPANT:
2795 rc = match_isinlist(US"non-participant", &arg, 0, NULL,
2796 NULL, MCL_STRING, TRUE, NULL);
2798 case DK_EXIM_RESULT_GOOD:
2799 rc = match_isinlist(US"good", &arg, 0, NULL,
2800 NULL, MCL_STRING, TRUE, NULL);
2802 case DK_EXIM_RESULT_BAD:
2803 rc = match_isinlist(US"bad", &arg, 0, NULL,
2804 NULL, MCL_STRING, TRUE, NULL);
2812 rc = verify_check_dnsbl(&arg);
2816 rc = match_isinlist(addr->domain, &arg, 0, &domainlist_anchor,
2817 addr->domain_cache, MCL_DOMAIN, TRUE, &deliver_domain_data);
2820 /* The value in tls_cipher is the full cipher name, for example,
2821 TLSv1:DES-CBC3-SHA:168, whereas the values to test for are just the
2822 cipher names such as DES-CBC3-SHA. But program defensively. We don't know
2823 what may in practice come out of the SSL library - which at the time of
2824 writing is poorly documented. */
2826 case ACLC_ENCRYPTED:
2827 if (tls_cipher == NULL) rc = FAIL; else
2829 uschar *endcipher = NULL;
2830 uschar *cipher = Ustrchr(tls_cipher, ':');
2831 if (cipher == NULL) cipher = tls_cipher; else
2833 endcipher = Ustrchr(++cipher, ':');
2834 if (endcipher != NULL) *endcipher = 0;
2836 rc = match_isinlist(cipher, &arg, 0, NULL, NULL, MCL_STRING, TRUE, NULL);
2837 if (endcipher != NULL) *endcipher = ':';
2841 /* Use verify_check_this_host() instead of verify_check_host() so that
2842 we can pass over &host_data to catch any looked up data. Once it has been
2843 set, it retains its value so that it's still there if another ACL verb
2844 comes through here and uses the cache. However, we must put it into
2845 permanent store in case it is also expected to be used in a subsequent
2846 message in the same SMTP connection. */
2849 rc = verify_check_this_host(&arg, sender_host_cache, NULL,
2850 (sender_host_address == NULL)? US"" : sender_host_address, &host_data);
2851 if (host_data != NULL) host_data = string_copy_malloc(host_data);
2854 case ACLC_LOCAL_PARTS:
2855 rc = match_isinlist(addr->cc_local_part, &arg, 0,
2856 &localpartlist_anchor, addr->localpart_cache, MCL_LOCALPART, TRUE,
2857 &deliver_localpart_data);
2860 case ACLC_LOG_REJECT_TARGET:
2866 while ((ss = string_nextinlist(&s, &sep, big_buffer, big_buffer_size))
2869 if (Ustrcmp(ss, "main") == 0) logbits |= LOG_MAIN;
2870 else if (Ustrcmp(ss, "panic") == 0) logbits |= LOG_PANIC;
2871 else if (Ustrcmp(ss, "reject") == 0) logbits |= LOG_REJECT;
2874 logbits |= LOG_MAIN|LOG_REJECT;
2875 log_write(0, LOG_MAIN|LOG_PANIC, "unknown log name \"%s\" in "
2876 "\"log_reject_target\" in %s ACL", ss, acl_wherenames[where]);
2879 log_reject_target = logbits;
2892 if (Ustrncmp(s, "main", 4) == 0)
2893 { logbits |= LOG_MAIN; s += 4; }
2894 else if (Ustrncmp(s, "panic", 5) == 0)
2895 { logbits |= LOG_PANIC; s += 5; }
2896 else if (Ustrncmp(s, "reject", 6) == 0)
2897 { logbits |= LOG_REJECT; s += 6; }
2900 logbits = LOG_MAIN|LOG_PANIC;
2901 s = string_sprintf(":unknown log name in \"%s\" in "
2902 "\"logwrite\" in %s ACL", arg, acl_wherenames[where]);
2908 while (isspace(*s)) s++;
2911 if (logbits == 0) logbits = LOG_MAIN;
2912 log_write(0, logbits, "%s", string_printing(s));
2916 #ifdef WITH_CONTENT_SCAN
2919 /* Separate the regular expression and any optional parameters. */
2920 uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size);
2921 /* Run the malware backend. */
2923 /* Modify return code based upon the existance of options. */
2924 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2926 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
2928 /* FAIL so that the message is passed to the next ACL */
2935 case ACLC_MIME_REGEX:
2936 rc = mime_regex(&arg);
2940 case ACLC_RATELIMIT:
2941 rc = acl_ratelimit(arg, where, log_msgptr);
2944 case ACLC_RECIPIENTS:
2945 rc = match_address_list(addr->address, TRUE, TRUE, &arg, NULL, -1, 0,
2949 #ifdef WITH_CONTENT_SCAN
2955 case ACLC_SENDER_DOMAINS:
2958 sdomain = Ustrrchr(sender_address, '@');
2959 sdomain = (sdomain == NULL)? US"" : sdomain + 1;
2960 rc = match_isinlist(sdomain, &arg, 0, &domainlist_anchor,
2961 sender_domain_cache, MCL_DOMAIN, TRUE, NULL);
2966 rc = match_address_list(sender_address, TRUE, TRUE, &arg,
2967 sender_address_cache, -1, 0, &sender_data);
2970 /* Connection variables must persist forever */
2974 int old_pool = store_pool;
2975 if (cb->u.varname[0] == 'c') store_pool = POOL_PERM;
2976 acl_var_create(cb->u.varname)->data.ptr = string_copy(arg);
2977 store_pool = old_pool;
2981 #ifdef WITH_CONTENT_SCAN
2984 /* Seperate the regular expression and any optional parameters. */
2985 uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size);
2986 /* Run the spam backend. */
2988 /* Modify return code based upon the existance of options. */
2989 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2991 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
2993 /* FAIL so that the message is passed to the next ACL */
3001 #ifdef EXPERIMENTAL_SPF
3003 rc = spf_process(&arg, sender_address);
3007 /* If the verb is WARN, discard any user message from verification, because
3008 such messages are SMTP responses, not header additions. The latter come
3009 only from explicit "message" modifiers. However, put the user message into
3010 $acl_verify_message so it can be used in subsequent conditions or modifiers
3011 (until something changes it). */
3014 rc = acl_verify(where, addr, arg, user_msgptr, log_msgptr, basic_errno);
3015 acl_verify_message = *user_msgptr;
3016 if (verb == ACL_WARN) *user_msgptr = NULL;
3020 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown "
3021 "condition %d", cb->type);
3025 /* If a condition was negated, invert OK/FAIL. */
3027 if (!cond_modifiers[cb->type] && cb->u.negated)
3029 if (rc == OK) rc = FAIL;
3030 else if (rc == FAIL || rc == FAIL_DROP) rc = OK;
3033 if (rc != OK) break; /* Conditions loop */
3037 /* If the result is the one for which "message" and/or "log_message" are used,
3038 handle the values of these options. Most verbs have but a single return for
3039 which the messages are relevant, but for "discard", it's useful to have the log
3040 message both when it succeeds and when it fails. Also, for an "accept" that
3041 appears in a QUIT ACL, we want to handle the user message. Since only "accept"
3042 and "warn" are permitted in that ACL, we don't need to test the verb.
3044 These modifiers act in different ways:
3046 "message" is a user message that will be included in an SMTP response. Unless
3047 it is empty, it overrides any previously set user message.
3049 "log_message" is a non-user message, and it adds to any existing non-user
3050 message that is already set.
3052 If there isn't a log message set, we make it the same as the user message. */
3054 if (((rc == FAIL_DROP)? FAIL : rc) == msgcond[verb] ||
3055 (verb == ACL_DISCARD && rc == OK) ||
3056 (where == ACL_WHERE_QUIT))
3060 /* If the verb is "warn", messages generated by conditions (verification or
3061 nested ACLs) are discarded. Only messages specified at this level are used.
3062 However, the value of an existing message is available in $acl_verify_message
3063 during expansions. */
3065 uschar *old_user_msgptr = *user_msgptr;
3066 uschar *old_log_msgptr = (*log_msgptr != NULL)? *log_msgptr : old_user_msgptr;
3068 if (verb == ACL_WARN) *log_msgptr = *user_msgptr = NULL;
3070 if (user_message != NULL)
3072 acl_verify_message = old_user_msgptr;
3073 expmessage = expand_string(user_message);
3074 if (expmessage == NULL)
3076 if (!expand_string_forcedfail)
3077 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
3078 user_message, expand_string_message);
3080 else if (expmessage[0] != 0) *user_msgptr = expmessage;
3083 if (log_message != NULL)
3085 acl_verify_message = old_log_msgptr;
3086 expmessage = expand_string(log_message);
3087 if (expmessage == NULL)
3089 if (!expand_string_forcedfail)
3090 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
3091 log_message, expand_string_message);
3093 else if (expmessage[0] != 0)
3095 *log_msgptr = (*log_msgptr == NULL)? expmessage :
3096 string_sprintf("%s: %s", expmessage, *log_msgptr);
3100 /* If no log message, default it to the user message */
3102 if (*log_msgptr == NULL) *log_msgptr = *user_msgptr;
3105 acl_verify_message = NULL;
3113 /*************************************************
3114 * Get line from a literal ACL *
3115 *************************************************/
3117 /* This function is passed to acl_read() in order to extract individual lines
3118 of a literal ACL, which we access via static pointers. We can destroy the
3119 contents because this is called only once (the compiled ACL is remembered).
3121 This code is intended to treat the data in the same way as lines in the main
3122 Exim configuration file. That is:
3124 . Leading spaces are ignored.
3126 . A \ at the end of a line is a continuation - trailing spaces after the \
3127 are permitted (this is because I don't believe in making invisible things
3128 significant). Leading spaces on the continued part of a line are ignored.
3130 . Physical lines starting (significantly) with # are totally ignored, and
3131 may appear within a sequence of backslash-continued lines.
3133 . Blank lines are ignored, but will end a sequence of continuations.
3136 Returns: a pointer to the next line
3140 static uschar *acl_text; /* Current pointer in the text */
3141 static uschar *acl_text_end; /* Points one past the terminating '0' */
3149 /* This loop handles leading blank lines and comments. */
3153 while (isspace(*acl_text)) acl_text++; /* Leading spaces/empty lines */
3154 if (*acl_text == 0) return NULL; /* No more data */
3155 yield = acl_text; /* Potential data line */
3157 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3159 /* If we hit the end before a newline, we have the whole logical line. If
3160 it's a comment, there's no more data to be given. Otherwise, yield it. */
3162 if (*acl_text == 0) return (*yield == '#')? NULL : yield;
3164 /* After reaching a newline, end this loop if the physical line does not
3165 start with '#'. If it does, it's a comment, and the loop continues. */
3167 if (*yield != '#') break;
3170 /* This loop handles continuations. We know we have some real data, ending in
3171 newline. See if there is a continuation marker at the end (ignoring trailing
3172 white space). We know that *yield is not white space, so no need to test for
3173 cont > yield in the backwards scanning loop. */
3178 for (cont = acl_text - 1; isspace(*cont); cont--);
3180 /* If no continuation follows, we are done. Mark the end of the line and
3189 /* We have encountered a continuation. Skip over whitespace at the start of
3190 the next line, and indeed the whole of the next line or lines if they are
3195 while (*(++acl_text) == ' ' || *acl_text == '\t');
3196 if (*acl_text != '#') break;
3197 while (*(++acl_text) != 0 && *acl_text != '\n');
3200 /* We have the start of a continuation line. Move all the rest of the data
3201 to join onto the previous line, and then find its end. If the end is not a
3202 newline, we are done. Otherwise loop to look for another continuation. */
3204 memmove(cont, acl_text, acl_text_end - acl_text);
3205 acl_text_end -= acl_text - cont;
3207 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3208 if (*acl_text == 0) return yield;
3211 /* Control does not reach here */
3218 /*************************************************
3219 * Check access using an ACL *
3220 *************************************************/
3222 /* This function is called from address_check. It may recurse via
3223 acl_check_condition() - hence the use of a level to stop looping. The ACL is
3224 passed as a string which is expanded. A forced failure implies no access check
3225 is required. If the result is a single word, it is taken as the name of an ACL
3226 which is sought in the global ACL tree. Otherwise, it is taken as literal ACL
3227 text, complete with newlines, and parsed as such. In both cases, the ACL check
3228 is then run. This function uses an auxiliary function for acl_read() to call
3229 for reading individual lines of a literal ACL. This is acl_getline(), which
3230 appears immediately above.
3233 where where called from
3234 addr address item when called from RCPT; otherwise NULL
3235 s the input string; NULL is the same as an empty ACL => DENY
3236 level the nesting level
3237 user_msgptr where to put a user error (for SMTP response)
3238 log_msgptr where to put a logging message (not for SMTP response)
3240 Returns: OK access is granted
3241 DISCARD access is apparently granted...
3242 FAIL access is denied
3243 FAIL_DROP access is denied; drop the connection
3244 DEFER can't tell at the moment
3249 acl_check_internal(int where, address_item *addr, uschar *s, int level,
3250 uschar **user_msgptr, uschar **log_msgptr)
3253 acl_block *acl = NULL;
3254 uschar *acl_name = US"inline ACL";
3257 /* Catch configuration loops */
3261 *log_msgptr = US"ACL nested too deep: possible loop";
3267 HDEBUG(D_acl) debug_printf("ACL is NULL: implicit DENY\n");
3271 /* At top level, we expand the incoming string. At lower levels, it has already
3272 been expanded as part of condition processing. */
3276 ss = expand_string(s);
3279 if (expand_string_forcedfail) return OK;
3280 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s", s,
3281 expand_string_message);
3287 while (isspace(*ss))ss++;
3289 /* If we can't find a named ACL, the default is to parse it as an inline one.
3290 (Unless it begins with a slash; non-existent files give rise to an error.) */
3294 /* Handle the case of a string that does not contain any spaces. Look for a
3295 named ACL among those read from the configuration, or a previously read file.
3296 It is possible that the pointer to the ACL is NULL if the configuration
3297 contains a name with no data. If not found, and the text begins with '/',
3298 read an ACL from a file, and save it so it can be re-used. */
3300 if (Ustrchr(ss, ' ') == NULL)
3302 tree_node *t = tree_search(acl_anchor, ss);
3305 acl = (acl_block *)(t->data.ptr);
3308 HDEBUG(D_acl) debug_printf("ACL \"%s\" is empty: implicit DENY\n", ss);
3311 acl_name = string_sprintf("ACL \"%s\"", ss);
3312 HDEBUG(D_acl) debug_printf("using ACL \"%s\"\n", ss);
3315 else if (*ss == '/')
3317 struct stat statbuf;
3318 fd = Uopen(ss, O_RDONLY, 0);
3321 *log_msgptr = string_sprintf("failed to open ACL file \"%s\": %s", ss,
3326 if (fstat(fd, &statbuf) != 0)
3328 *log_msgptr = string_sprintf("failed to fstat ACL file \"%s\": %s", ss,
3333 acl_text = store_get(statbuf.st_size + 1);
3334 acl_text_end = acl_text + statbuf.st_size + 1;
3336 if (read(fd, acl_text, statbuf.st_size) != statbuf.st_size)
3338 *log_msgptr = string_sprintf("failed to read ACL file \"%s\": %s",
3339 ss, strerror(errno));
3342 acl_text[statbuf.st_size] = 0;
3345 acl_name = string_sprintf("ACL \"%s\"", ss);
3346 HDEBUG(D_acl) debug_printf("read ACL from file %s\n", ss);
3350 /* Parse an ACL that is still in text form. If it came from a file, remember it
3351 in the ACL tree, having read it into the POOL_PERM store pool so that it
3352 persists between multiple messages. */
3356 int old_pool = store_pool;
3357 if (fd >= 0) store_pool = POOL_PERM;
3358 acl = acl_read(acl_getline, log_msgptr);
3359 store_pool = old_pool;
3360 if (acl == NULL && *log_msgptr != NULL) return ERROR;
3363 tree_node *t = store_get_perm(sizeof(tree_node) + Ustrlen(ss));
3364 Ustrcpy(t->name, ss);
3366 (void)tree_insertnode(&acl_anchor, t);
3370 /* Now we have an ACL to use. It's possible it may be NULL. */
3375 int basic_errno = 0;
3376 BOOL endpass_seen = FALSE;
3378 *log_msgptr = *user_msgptr = NULL;
3379 acl_temp_details = FALSE;
3381 if (where == ACL_WHERE_QUIT &&
3382 acl->verb != ACL_ACCEPT &&
3383 acl->verb != ACL_WARN)
3385 *log_msgptr = string_sprintf("\"%s\" is not allowed in a QUIT ACL",
3390 HDEBUG(D_acl) debug_printf("processing \"%s\"\n", verbs[acl->verb]);
3392 /* Clear out any search error message from a previous check before testing
3395 search_error_message = NULL;
3396 cond = acl_check_condition(acl->verb, acl->condition, where, addr, level,
3397 &endpass_seen, user_msgptr, log_msgptr, &basic_errno);
3399 /* Handle special returns: DEFER causes a return except on a WARN verb;
3400 ERROR always causes a return. */
3405 HDEBUG(D_acl) debug_printf("%s: condition test deferred\n", verbs[acl->verb]);
3406 if (basic_errno != ERRNO_CALLOUTDEFER)
3408 if (search_error_message != NULL && *search_error_message != 0)
3409 *log_msgptr = search_error_message;
3410 if (smtp_return_error_details) acl_temp_details = TRUE;
3414 acl_temp_details = TRUE;
3416 if (acl->verb != ACL_WARN) return DEFER;
3419 default: /* Paranoia */
3421 HDEBUG(D_acl) debug_printf("%s: condition test error\n", verbs[acl->verb]);
3425 HDEBUG(D_acl) debug_printf("%s: condition test succeeded\n",
3430 HDEBUG(D_acl) debug_printf("%s: condition test failed\n", verbs[acl->verb]);
3433 /* DISCARD and DROP can happen only from a nested ACL condition, and
3434 DISCARD can happen only for an "accept" or "discard" verb. */
3437 HDEBUG(D_acl) debug_printf("%s: condition test yielded \"discard\"\n",
3442 HDEBUG(D_acl) debug_printf("%s: condition test yielded \"drop\"\n",
3447 /* At this point, cond for most verbs is either OK or FAIL or (as a result of
3448 a nested ACL condition) FAIL_DROP. However, for WARN, cond may be DEFER, and
3449 for ACCEPT and DISCARD, it may be DISCARD after a nested ACL call. */
3454 if (cond == OK || cond == DISCARD) return cond;
3457 HDEBUG(D_acl) debug_printf("accept: endpass encountered - denying access\n");
3465 acl_temp_details = TRUE;
3471 if (cond == OK) return FAIL;
3475 if (cond == OK || cond == DISCARD) return DISCARD;
3478 HDEBUG(D_acl) debug_printf("discard: endpass encountered - denying access\n");
3484 if (cond == OK) return FAIL_DROP;
3488 if (cond != OK) return cond;
3493 acl_warn(where, *user_msgptr, *log_msgptr);
3494 else if (cond == DEFER && (log_extra_selector & LX_acl_warn_skipped) != 0)
3495 log_write(0, LOG_MAIN, "%s Warning: ACL \"warn\" statement skipped: "
3496 "condition test deferred%s%s", host_and_ident(TRUE),
3497 (*log_msgptr == NULL)? US"" : US": ",
3498 (*log_msgptr == NULL)? US"" : *log_msgptr);
3499 *log_msgptr = *user_msgptr = NULL; /* In case implicit DENY follows */
3503 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown verb %d",
3508 /* Pass to the next ACL item */
3513 /* We have reached the end of the ACL. This is an implicit DENY. */
3515 HDEBUG(D_acl) debug_printf("end of %s: implicit DENY\n", acl_name);
3520 /*************************************************
3521 * Check access using an ACL *
3522 *************************************************/
3524 /* This is the external interface for ACL checks. It sets up an address and the
3525 expansions for $domain and $local_part when called after RCPT, then calls
3526 acl_check_internal() to do the actual work.
3529 where ACL_WHERE_xxxx indicating where called from
3530 recipient RCPT address for RCPT check, else NULL
3531 s the input string; NULL is the same as an empty ACL => DENY
3532 user_msgptr where to put a user error (for SMTP response)
3533 log_msgptr where to put a logging message (not for SMTP response)
3535 Returns: OK access is granted by an ACCEPT verb
3536 DISCARD access is granted by a DISCARD verb
3537 FAIL access is denied
3538 FAIL_DROP access is denied; drop the connection
3539 DEFER can't tell at the moment
3544 acl_check(int where, uschar *recipient, uschar *s, uschar **user_msgptr,
3545 uschar **log_msgptr)
3549 address_item *addr = NULL;
3551 *user_msgptr = *log_msgptr = NULL;
3552 sender_verified_failed = NULL;
3553 ratelimiters_cmd = NULL;
3554 log_reject_target = LOG_MAIN|LOG_REJECT;
3556 if (where == ACL_WHERE_RCPT)
3558 adb = address_defaults;
3560 addr->address = recipient;
3561 if (deliver_split_address(addr) == DEFER)
3563 *log_msgptr = US"defer in percent_hack_domains check";
3566 deliver_domain = addr->domain;
3567 deliver_localpart = addr->local_part;
3570 rc = acl_check_internal(where, addr, s, 0, user_msgptr, log_msgptr);
3572 deliver_domain = deliver_localpart = deliver_address_data =
3573 sender_address_data = NULL;
3575 /* A DISCARD response is permitted only for message ACLs, excluding the PREDATA
3576 ACL, which is really in the middle of an SMTP command. */
3580 if (where > ACL_WHERE_NOTSMTP || where == ACL_WHERE_PREDATA)
3582 log_write(0, LOG_MAIN|LOG_PANIC, "\"discard\" verb not allowed in %s "
3583 "ACL", acl_wherenames[where]);
3589 /* A DROP response is not permitted from MAILAUTH */
3591 if (rc == FAIL_DROP && where == ACL_WHERE_MAILAUTH)
3593 log_write(0, LOG_MAIN|LOG_PANIC, "\"drop\" verb not allowed in %s "
3594 "ACL", acl_wherenames[where]);
3598 /* Before giving an error response, take a look at the length of any user
3599 message, and split it up into multiple lines if possible. */
3601 if (rc != OK && *user_msgptr != NULL && Ustrlen(*user_msgptr) > 75)
3603 uschar *s = *user_msgptr = string_copy(*user_msgptr);
3609 while (i < 75 && *ss != 0 && *ss != '\n') ss++, i++;
3610 if (*ss == 0) break;
3617 while (--t > s + 35)
3621 if (t[-1] == ':') { tt = t; break; }
3622 if (tt == NULL) tt = t;
3626 if (tt == NULL) /* Can't split behind - try ahead */
3631 if (*t == ' ' || *t == '\n')
3637 if (tt == NULL) break; /* Can't find anywhere to split */
3649 /*************************************************
3650 * Create ACL variable *
3651 *************************************************/
3653 /* Create an ACL variable or reuse an existing one. ACL variables are in a
3654 binary tree (see tree.c) with acl_var_c and acl_var_m as root nodes.
3657 name pointer to the variable's name, starting with c or m
3659 Returns the pointer to variable's tree node
3663 acl_var_create(uschar *name)
3665 tree_node *node, **root;
3666 root = (name[0] == 'c')? &acl_var_c : &acl_var_m;
3667 node = tree_search(*root, name);
3670 node = store_get(sizeof(tree_node) + Ustrlen(name));
3671 Ustrcpy(node->name, name);
3672 (void)tree_insertnode(root, node);
3674 node->data.ptr = NULL;
3680 /*************************************************
3681 * Write an ACL variable in spool format *
3682 *************************************************/
3684 /* This function is used as a callback for tree_walk when writing variables to
3685 the spool file. To retain spool file compatibility, what is written is -aclc or
3686 -aclm followed by the rest of the name and the data length, space separated,
3687 then the value itself, starting on a new line, and terminated by an additional
3688 newline. When we had only numbered ACL variables, the first line might look
3689 like this: "-aclc 5 20". Now it might be "-aclc foo 20" for the variable called
3693 name of the variable
3694 value of the variable
3695 ctx FILE pointer (as a void pointer)
3701 acl_var_write(uschar *name, uschar *value, void *ctx)
3703 FILE *f = (FILE *)ctx;
3704 fprintf(f, "-acl%c %s %d\n%s\n", name[0], name+1, Ustrlen(value), value);