1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2017 */
6 /* See the file NOTICE for conditions of use and distribution. */
8 /* Code for handling Access Control Lists (ACLs) */
13 /* Default callout timeout */
15 #define CALLOUT_TIMEOUT_DEFAULT 30
17 /* ACL verb codes - keep in step with the table of verbs that follows */
19 enum { ACL_ACCEPT, ACL_DEFER, ACL_DENY, ACL_DISCARD, ACL_DROP, ACL_REQUIRE,
24 static uschar *verbs[] = {
25 [ACL_ACCEPT] = US"accept",
26 [ACL_DEFER] = US"defer",
27 [ACL_DENY] = US"deny",
28 [ACL_DISCARD] = US"discard",
29 [ACL_DROP] = US"drop",
30 [ACL_REQUIRE] = US"require",
34 /* For each verb, the conditions for which "message" or "log_message" are used
35 are held as a bitmap. This is to avoid expanding the strings unnecessarily. For
36 "accept", the FAIL case is used only after "endpass", but that is selected in
39 static int msgcond[] = {
40 [ACL_ACCEPT] = BIT(OK) | BIT(FAIL) | BIT(FAIL_DROP),
41 [ACL_DEFER] = BIT(OK),
43 [ACL_DISCARD] = BIT(OK) | BIT(FAIL) | BIT(FAIL_DROP),
45 [ACL_REQUIRE] = BIT(FAIL) | BIT(FAIL_DROP),
49 /* ACL condition and modifier codes - keep in step with the table that
56 #ifdef EXPERIMENTAL_BRIGHTMAIL
62 #ifdef EXPERIMENTAL_DCC
65 #ifdef WITH_CONTENT_SCAN
73 #ifdef EXPERIMENTAL_DMARC
83 ACLC_LOG_REJECT_TARGET,
85 #ifdef WITH_CONTENT_SCAN
89 #ifdef WITH_CONTENT_SCAN
95 #ifdef WITH_CONTENT_SCAN
102 #ifdef WITH_CONTENT_SCAN
112 /* ACL conditions/modifiers: "delay", "control", "continue", "endpass",
113 "message", "log_message", "log_reject_target", "logwrite", "queue" and "set" are
114 modifiers that look like conditions but always return TRUE. They are used for
115 their side effects. */
117 typedef struct condition_def {
120 /* Flag to indicate the condition/modifier has a string expansion done
121 at the outer level. In the other cases, expansion already occurs in the
122 checking functions. */
123 BOOL expand_at_top:1;
127 /* Bit map vector of which conditions and modifiers are not allowed at certain
128 times. For each condition and modifier, there's a bitmap of dis-allowed times.
129 For some, it is easier to specify the negation of a small number of allowed
135 static condition_def conditions[] = {
136 [ACLC_ACL] = { US"acl", FALSE, FALSE, 0 },
138 [ACLC_ADD_HEADER] = { US"add_header", TRUE, TRUE,
140 ~(ACL_BIT_MAIL | ACL_BIT_RCPT |
141 ACL_BIT_PREDATA | ACL_BIT_DATA |
145 ACL_BIT_MIME | ACL_BIT_NOTSMTP |
147 ACL_BIT_NOTSMTP_START),
150 [ACLC_AUTHENTICATED] = { US"authenticated", FALSE, FALSE,
151 ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START |
152 ACL_BIT_CONNECT | ACL_BIT_HELO,
154 #ifdef EXPERIMENTAL_BRIGHTMAIL
155 [ACLC_BMI_OPTIN] = { US"bmi_optin", TRUE, TRUE,
157 ACL_BIT_CONNECT | ACL_BIT_HELO |
158 ACL_BIT_DATA | ACL_BIT_MIME |
159 # ifndef DISABLE_PRDR
162 ACL_BIT_ETRN | ACL_BIT_EXPN |
164 ACL_BIT_MAIL | ACL_BIT_STARTTLS |
165 ACL_BIT_VRFY | ACL_BIT_PREDATA |
166 ACL_BIT_NOTSMTP_START,
169 [ACLC_CONDITION] = { US"condition", TRUE, FALSE, 0 },
170 [ACLC_CONTINUE] = { US"continue", TRUE, TRUE, 0 },
172 /* Certain types of control are always allowed, so we let it through
173 always and check in the control processing itself. */
174 [ACLC_CONTROL] = { US"control", TRUE, TRUE, 0 },
176 #ifdef EXPERIMENTAL_DCC
177 [ACLC_DCC] = { US"dcc", TRUE, FALSE,
180 # ifndef DISABLE_PRDR
186 #ifdef WITH_CONTENT_SCAN
187 [ACLC_DECODE] = { US"decode", TRUE, FALSE, (unsigned int) ~ACL_BIT_MIME },
190 [ACLC_DELAY] = { US"delay", TRUE, TRUE, ACL_BIT_NOTQUIT },
192 [ACLC_DKIM_SIGNER] = { US"dkim_signers", TRUE, FALSE, (unsigned int) ~ACL_BIT_DKIM },
193 [ACLC_DKIM_STATUS] = { US"dkim_status", TRUE, FALSE, (unsigned int) ~ACL_BIT_DKIM },
195 #ifdef EXPERIMENTAL_DMARC
196 [ACLC_DMARC_STATUS] = { US"dmarc_status", TRUE, FALSE, (unsigned int) ~ACL_BIT_DATA },
199 /* Explicit key lookups can be made in non-smtp ACLs so pass
200 always and check in the verify processing itself. */
201 [ACLC_DNSLISTS] = { US"dnslists", TRUE, FALSE, 0 },
203 [ACLC_DOMAINS] = { US"domains", FALSE, FALSE,
205 ~(ACL_BIT_RCPT | ACL_BIT_VRFY
211 [ACLC_ENCRYPTED] = { US"encrypted", FALSE, FALSE,
212 ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START |
216 [ACLC_ENDPASS] = { US"endpass", TRUE, TRUE, 0 },
218 [ACLC_HOSTS] = { US"hosts", FALSE, FALSE,
219 ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START,
221 [ACLC_LOCAL_PARTS] = { US"local_parts", FALSE, FALSE,
223 ~(ACL_BIT_RCPT | ACL_BIT_VRFY
230 [ACLC_LOG_MESSAGE] = { US"log_message", TRUE, TRUE, 0 },
231 [ACLC_LOG_REJECT_TARGET] = { US"log_reject_target", TRUE, TRUE, 0 },
232 [ACLC_LOGWRITE] = { US"logwrite", TRUE, TRUE, 0 },
234 #ifdef WITH_CONTENT_SCAN
235 [ACLC_MALWARE] = { US"malware", TRUE, FALSE,
238 # ifndef DISABLE_PRDR
245 [ACLC_MESSAGE] = { US"message", TRUE, TRUE, 0 },
246 #ifdef WITH_CONTENT_SCAN
247 [ACLC_MIME_REGEX] = { US"mime_regex", TRUE, FALSE, (unsigned int) ~ACL_BIT_MIME },
250 [ACLC_QUEUE] = { US"queue", TRUE, TRUE,
258 [ACLC_RATELIMIT] = { US"ratelimit", TRUE, FALSE, 0 },
259 [ACLC_RECIPIENTS] = { US"recipients", FALSE, FALSE, (unsigned int) ~ACL_BIT_RCPT },
261 #ifdef WITH_CONTENT_SCAN
262 [ACLC_REGEX] = { US"regex", TRUE, FALSE,
265 # ifndef DISABLE_PRDR
273 [ACLC_REMOVE_HEADER] = { US"remove_header", TRUE, TRUE,
275 ~(ACL_BIT_MAIL|ACL_BIT_RCPT |
276 ACL_BIT_PREDATA | ACL_BIT_DATA |
280 ACL_BIT_MIME | ACL_BIT_NOTSMTP |
281 ACL_BIT_NOTSMTP_START),
283 [ACLC_SENDER_DOMAINS] = { US"sender_domains", FALSE, FALSE,
284 ACL_BIT_AUTH | ACL_BIT_CONNECT |
286 ACL_BIT_MAILAUTH | ACL_BIT_QUIT |
287 ACL_BIT_ETRN | ACL_BIT_EXPN |
288 ACL_BIT_STARTTLS | ACL_BIT_VRFY,
290 [ACLC_SENDERS] = { US"senders", FALSE, FALSE,
291 ACL_BIT_AUTH | ACL_BIT_CONNECT |
293 ACL_BIT_MAILAUTH | ACL_BIT_QUIT |
294 ACL_BIT_ETRN | ACL_BIT_EXPN |
295 ACL_BIT_STARTTLS | ACL_BIT_VRFY,
298 [ACLC_SET] = { US"set", TRUE, TRUE, 0 },
300 #ifdef WITH_CONTENT_SCAN
301 [ACLC_SPAM] = { US"spam", TRUE, FALSE,
302 (unsigned int) ~(ACL_BIT_DATA |
303 # ifndef DISABLE_PRDR
310 [ACLC_SPF] = { US"spf", TRUE, FALSE,
311 ACL_BIT_AUTH | ACL_BIT_CONNECT |
312 ACL_BIT_HELO | ACL_BIT_MAILAUTH |
313 ACL_BIT_ETRN | ACL_BIT_EXPN |
314 ACL_BIT_STARTTLS | ACL_BIT_VRFY |
315 ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START,
317 [ACLC_SPF_GUESS] = { US"spf_guess", TRUE, FALSE,
318 ACL_BIT_AUTH | ACL_BIT_CONNECT |
319 ACL_BIT_HELO | ACL_BIT_MAILAUTH |
320 ACL_BIT_ETRN | ACL_BIT_EXPN |
321 ACL_BIT_STARTTLS | ACL_BIT_VRFY |
322 ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START,
325 [ACLC_UDPSEND] = { US"udpsend", TRUE, TRUE, 0 },
327 /* Certain types of verify are always allowed, so we let it through
328 always and check in the verify function itself */
329 [ACLC_VERIFY] = { US"verify", TRUE, FALSE, 0 },
334 /* Return values from decode_control(); used as index so keep in step
335 with the controls_list table that follows! */
338 CONTROL_AUTH_UNADVERTISED,
339 #ifdef EXPERIMENTAL_BRIGHTMAIL
342 CONTROL_CASEFUL_LOCAL_PART,
343 CONTROL_CASELOWER_LOCAL_PART,
344 CONTROL_CUTTHROUGH_DELIVERY,
349 #ifdef EXPERIMENTAL_DMARC
350 CONTROL_DMARC_VERIFY,
351 CONTROL_DMARC_FORENSIC,
354 CONTROL_ENFORCE_SYNC,
355 CONTROL_ERROR, /* pseudo-value for decode errors */
360 CONTROL_NO_CALLOUT_FLUSH,
361 CONTROL_NO_DELAY_FLUSH,
362 CONTROL_NO_ENFORCE_SYNC,
363 #ifdef WITH_CONTENT_SCAN
364 CONTROL_NO_MBOX_UNSPOOL,
366 CONTROL_NO_MULTILINE,
367 CONTROL_NO_PIPELINING,
371 CONTROL_SUPPRESS_LOCAL_FIXUPS,
373 CONTROL_UTF8_DOWNCONVERT,
379 /* Structure listing various control arguments, with their characteristics.
380 For each control, there's a bitmap of dis-allowed times. For some, it is easier
381 to specify the negation of a small number of allowed times. */
383 typedef struct control_def {
385 BOOL has_option; /* Has /option(s) following */
386 unsigned forbids; /* bitmap of dis-allowed times */
389 static control_def controls_list[] = {
390 /* name has_option forbids */
391 [CONTROL_AUTH_UNADVERTISED] =
392 { US"allow_auth_unadvertised", FALSE,
394 ~(ACL_BIT_CONNECT | ACL_BIT_HELO)
396 #ifdef EXPERIMENTAL_BRIGHTMAIL
398 { US"bmi_run", FALSE, 0 },
400 [CONTROL_CASEFUL_LOCAL_PART] =
401 { US"caseful_local_part", FALSE, (unsigned) ~ACL_BIT_RCPT },
402 [CONTROL_CASELOWER_LOCAL_PART] =
403 { US"caselower_local_part", FALSE, (unsigned) ~ACL_BIT_RCPT },
404 [CONTROL_CUTTHROUGH_DELIVERY] =
405 { US"cutthrough_delivery", TRUE, 0 },
407 { US"debug", TRUE, 0 },
410 [CONTROL_DKIM_VERIFY] =
411 { US"dkim_disable_verify", FALSE,
412 ACL_BIT_DATA | ACL_BIT_NOTSMTP |
413 # ifndef DISABLE_PRDR
416 ACL_BIT_NOTSMTP_START
420 #ifdef EXPERIMENTAL_DMARC
421 [CONTROL_DMARC_VERIFY] =
422 { US"dmarc_disable_verify", FALSE,
423 ACL_BIT_DATA | ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START
425 [CONTROL_DMARC_FORENSIC] =
426 { US"dmarc_enable_forensic", FALSE,
427 ACL_BIT_DATA | ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START
433 ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START | ACL_BIT_NOTQUIT
435 [CONTROL_ENFORCE_SYNC] =
436 { US"enforce_sync", FALSE,
437 ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START
440 /* Pseudo-value for decode errors */
442 { US"error", FALSE, 0 },
444 [CONTROL_FAKEDEFER] =
445 { US"fakedefer", TRUE,
447 ~(ACL_BIT_MAIL | ACL_BIT_RCPT |
448 ACL_BIT_PREDATA | ACL_BIT_DATA |
454 [CONTROL_FAKEREJECT] =
455 { US"fakereject", TRUE,
457 ~(ACL_BIT_MAIL | ACL_BIT_RCPT |
458 ACL_BIT_PREDATA | ACL_BIT_DATA |
467 ~(ACL_BIT_MAIL | ACL_BIT_RCPT |
468 ACL_BIT_PREDATA | ACL_BIT_DATA |
469 // ACL_BIT_PRDR| /* Not allow one user to freeze for all */
470 ACL_BIT_NOTSMTP | ACL_BIT_MIME)
473 [CONTROL_NO_CALLOUT_FLUSH] =
474 { US"no_callout_flush", FALSE,
475 ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START
477 [CONTROL_NO_DELAY_FLUSH] =
478 { US"no_delay_flush", FALSE,
479 ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START
482 [CONTROL_NO_ENFORCE_SYNC] =
483 { US"no_enforce_sync", FALSE,
484 ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START
486 #ifdef WITH_CONTENT_SCAN
487 [CONTROL_NO_MBOX_UNSPOOL] =
488 { US"no_mbox_unspool", FALSE,
490 ~(ACL_BIT_MAIL | ACL_BIT_RCPT |
491 ACL_BIT_PREDATA | ACL_BIT_DATA |
492 // ACL_BIT_PRDR| /* Not allow one user to freeze for all */
496 [CONTROL_NO_MULTILINE] =
497 { US"no_multiline_responses", FALSE,
498 ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START
500 [CONTROL_NO_PIPELINING] =
501 { US"no_pipelining", FALSE,
502 ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START
505 [CONTROL_QUEUE_ONLY] =
506 { US"queue_only", FALSE,
508 ~(ACL_BIT_MAIL | ACL_BIT_RCPT |
509 ACL_BIT_PREDATA | ACL_BIT_DATA |
510 // ACL_BIT_PRDR| /* Not allow one user to freeze for all */
511 ACL_BIT_NOTSMTP | ACL_BIT_MIME)
513 [CONTROL_SUBMISSION] =
514 { US"submission", TRUE,
516 ~(ACL_BIT_MAIL | ACL_BIT_RCPT | ACL_BIT_PREDATA)
518 [CONTROL_SUPPRESS_LOCAL_FIXUPS] =
519 { US"suppress_local_fixups", FALSE,
521 ~(ACL_BIT_MAIL | ACL_BIT_RCPT | ACL_BIT_PREDATA |
522 ACL_BIT_NOTSMTP_START)
525 [CONTROL_UTF8_DOWNCONVERT] =
526 { US"utf8_downconvert", TRUE, 0 }
530 /* Support data structures for Client SMTP Authorization. acl_verify_csa()
531 caches its result in a tree to avoid repeated DNS queries. The result is an
532 integer code which is used as an index into the following tables of
533 explanatory strings and verification return codes. */
535 static tree_node *csa_cache = NULL;
537 enum { CSA_UNKNOWN, CSA_OK, CSA_DEFER_SRV, CSA_DEFER_ADDR,
538 CSA_FAIL_EXPLICIT, CSA_FAIL_DOMAIN, CSA_FAIL_NOADDR, CSA_FAIL_MISMATCH };
540 /* The acl_verify_csa() return code is translated into an acl_verify() return
541 code using the following table. It is OK unless the client is definitely not
542 authorized. This is because CSA is supposed to be optional for sending sites,
543 so recipients should not be too strict about checking it - especially because
544 DNS problems are quite likely to occur. It's possible to use $csa_status in
545 further ACL conditions to distinguish ok, unknown, and defer if required, but
546 the aim is to make the usual configuration simple. */
548 static int csa_return_code[] = {
551 [CSA_DEFER_SRV] = OK,
552 [CSA_DEFER_ADDR] = OK,
553 [CSA_FAIL_EXPLICIT] = FAIL,
554 [CSA_FAIL_DOMAIN] = FAIL,
555 [CSA_FAIL_NOADDR] = FAIL,
556 [CSA_FAIL_MISMATCH] = FAIL
559 static uschar *csa_status_string[] = {
560 [CSA_UNKNOWN] = US"unknown",
562 [CSA_DEFER_SRV] = US"defer",
563 [CSA_DEFER_ADDR] = US"defer",
564 [CSA_FAIL_EXPLICIT] = US"fail",
565 [CSA_FAIL_DOMAIN] = US"fail",
566 [CSA_FAIL_NOADDR] = US"fail",
567 [CSA_FAIL_MISMATCH] = US"fail"
570 static uschar *csa_reason_string[] = {
571 [CSA_UNKNOWN] = US"unknown",
573 [CSA_DEFER_SRV] = US"deferred (SRV lookup failed)",
574 [CSA_DEFER_ADDR] = US"deferred (target address lookup failed)",
575 [CSA_FAIL_EXPLICIT] = US"failed (explicit authorization required)",
576 [CSA_FAIL_DOMAIN] = US"failed (host name not authorized)",
577 [CSA_FAIL_NOADDR] = US"failed (no authorized addresses)",
578 [CSA_FAIL_MISMATCH] = US"failed (client address mismatch)"
581 /* Options for the ratelimit condition. Note that there are two variants of
582 the per_rcpt option, depending on the ACL that is used to measure the rate.
583 However any ACL must be able to look up per_rcpt rates in /noupdate mode,
584 so the two variants must have the same internal representation as well as
585 the same configuration string. */
588 RATE_PER_WHAT, RATE_PER_CLASH, RATE_PER_ADDR, RATE_PER_BYTE, RATE_PER_CMD,
589 RATE_PER_CONN, RATE_PER_MAIL, RATE_PER_RCPT, RATE_PER_ALLRCPTS
592 #define RATE_SET(var,new) \
593 (((var) == RATE_PER_WHAT) ? ((var) = RATE_##new) : ((var) = RATE_PER_CLASH))
595 static uschar *ratelimit_option_string[] = {
596 [RATE_PER_WHAT] = US"?",
597 [RATE_PER_CLASH] = US"!",
598 [RATE_PER_ADDR] = US"per_addr",
599 [RATE_PER_BYTE] = US"per_byte",
600 [RATE_PER_CMD] = US"per_cmd",
601 [RATE_PER_CONN] = US"per_conn",
602 [RATE_PER_MAIL] = US"per_mail",
603 [RATE_PER_RCPT] = US"per_rcpt",
604 [RATE_PER_ALLRCPTS] = US"per_rcpt"
607 /* Enable recursion between acl_check_internal() and acl_check_condition() */
609 static int acl_check_wargs(int, address_item *, const uschar *, uschar **,
613 /*************************************************
614 * Find control in list *
615 *************************************************/
617 /* The lists are always in order, so binary chop can be used.
620 name the control name to search for
621 ol the first entry in the control list
622 last one more than the offset of the last entry in the control list
624 Returns: index of a control entry, or -1 if not found
628 find_control(const uschar * name, control_def * ol, int last)
633 int middle = (first + last)/2;
634 uschar * s = ol[middle].name;
635 int c = Ustrncmp(name, s, Ustrlen(s));
636 if (c == 0) return middle;
637 else if (c > 0) first = middle + 1;
645 /*************************************************
646 * Pick out condition from list *
647 *************************************************/
649 /* Use a binary chop method
653 list list of conditions
656 Returns: offset in list, or -1 if not found
660 acl_checkcondition(uschar * name, condition_def * list, int end)
665 int mid = (start + end)/2;
666 int c = Ustrcmp(name, list[mid].name);
667 if (c == 0) return mid;
668 if (c < 0) end = mid;
669 else start = mid + 1;
675 /*************************************************
676 * Pick out name from list *
677 *************************************************/
679 /* Use a binary chop method
686 Returns: offset in list, or -1 if not found
690 acl_checkname(uschar *name, uschar **list, int end)
696 int mid = (start + end)/2;
697 int c = Ustrcmp(name, list[mid]);
698 if (c == 0) return mid;
699 if (c < 0) end = mid; else start = mid + 1;
706 /*************************************************
707 * Read and parse one ACL *
708 *************************************************/
710 /* This function is called both from readconf in order to parse the ACLs in the
711 configuration file, and also when an ACL is encountered dynamically (e.g. as
712 the result of an expansion). It is given a function to call in order to
713 retrieve the lines of the ACL. This function handles skipping comments and
714 blank lines (where relevant).
717 func function to get next line of ACL
718 error where to put an error message
720 Returns: pointer to ACL, or NULL
721 NULL can be legal (empty ACL); in this case error will be NULL
725 acl_read(uschar *(*func)(void), uschar **error)
727 acl_block *yield = NULL;
728 acl_block **lastp = &yield;
729 acl_block *this = NULL;
730 acl_condition_block *cond;
731 acl_condition_block **condp = NULL;
736 while ((s = (*func)()) != NULL)
739 BOOL negated = FALSE;
740 uschar *saveline = s;
743 /* Conditions (but not verbs) are allowed to be negated by an initial
746 while (isspace(*s)) s++;
753 /* Read the name of a verb or a condition, or the start of a new ACL, which
754 can be started by a name, or by a macro definition. */
756 s = readconf_readname(name, sizeof(name), s);
757 if (*s == ':' || (isupper(name[0]) && *s == '=')) return yield;
759 /* If a verb is unrecognized, it may be another condition or modifier that
760 continues the previous verb. */
762 if ((v = acl_checkname(name, verbs, nelem(verbs))) < 0)
766 *error = string_sprintf("unknown ACL verb \"%s\" in \"%s\"", name,
778 *error = string_sprintf("malformed ACL line \"%s\"", saveline);
781 this = store_get(sizeof(acl_block));
783 lastp = &(this->next);
786 this->condition = NULL;
787 condp = &(this->condition);
788 if (*s == 0) continue; /* No condition on this line */
794 s = readconf_readname(name, sizeof(name), s); /* Condition name */
797 /* Handle a condition or modifier. */
799 if ((c = acl_checkcondition(name, conditions, nelem(conditions))) < 0)
801 *error = string_sprintf("unknown ACL condition/modifier in \"%s\"",
806 /* The modifiers may not be negated */
808 if (negated && conditions[c].is_modifier)
810 *error = string_sprintf("ACL error: negation is not allowed with "
811 "\"%s\"", conditions[c].name);
815 /* ENDPASS may occur only with ACCEPT or DISCARD. */
817 if (c == ACLC_ENDPASS &&
818 this->verb != ACL_ACCEPT &&
819 this->verb != ACL_DISCARD)
821 *error = string_sprintf("ACL error: \"%s\" is not allowed with \"%s\"",
822 conditions[c].name, verbs[this->verb]);
826 cond = store_get(sizeof(acl_condition_block));
829 cond->u.negated = negated;
832 condp = &(cond->next);
834 /* The "set" modifier is different in that its argument is "name=value"
835 rather than just a value, and we can check the validity of the name, which
836 gives us a variable name to insert into the data block. The original ACL
837 variable names were acl_c0 ... acl_c9 and acl_m0 ... acl_m9. This was
838 extended to 20 of each type, but after that people successfully argued for
839 arbitrary names. In the new scheme, the names must start with acl_c or acl_m.
840 After that, we allow alphanumerics and underscores, but the first character
841 after c or m must be a digit or an underscore. This retains backwards
846 if ( Ustrncmp(s, "dkim_verify_status", 18) == 0
847 || Ustrncmp(s, "dkim_verify_reason", 18) == 0)
849 uschar * endptr = s+18;
851 if (isalnum(*endptr))
853 *error = string_sprintf("invalid variable name after \"set\" in ACL "
854 "modifier \"set %s\" "
855 "(only \"dkim_verify_status\" or \"dkim_verify_reason\" permitted)",
859 cond->u.varname = string_copyn(s, 18);
861 while (isspace(*s)) s++;
868 if (Ustrncmp(s, "acl_c", 5) != 0 &&
869 Ustrncmp(s, "acl_m", 5) != 0)
871 *error = string_sprintf("invalid variable name after \"set\" in ACL "
872 "modifier \"set %s\" (must start \"acl_c\" or \"acl_m\")", s);
877 if (!isdigit(*endptr) && *endptr != '_')
879 *error = string_sprintf("invalid variable name after \"set\" in ACL "
880 "modifier \"set %s\" (digit or underscore must follow acl_c or acl_m)",
885 while (*endptr != 0 && *endptr != '=' && !isspace(*endptr))
887 if (!isalnum(*endptr) && *endptr != '_')
889 *error = string_sprintf("invalid character \"%c\" in variable name "
890 "in ACL modifier \"set %s\"", *endptr, s);
896 cond->u.varname = string_copyn(s + 4, endptr - s - 4);
898 while (isspace(*s)) s++;
901 /* For "set", we are now positioned for the data. For the others, only
902 "endpass" has no data */
904 if (c != ACLC_ENDPASS)
908 *error = string_sprintf("\"=\" missing after ACL \"%s\" %s", name,
909 conditions[c].is_modifier ? US"modifier" : US"condition");
912 while (isspace(*s)) s++;
913 cond->arg = string_copy(s);
922 /*************************************************
923 * Set up added header line(s) *
924 *************************************************/
926 /* This function is called by the add_header modifier, and also from acl_warn()
927 to implement the now-deprecated way of adding header lines using "message" on a
928 "warn" verb. The argument is treated as a sequence of header lines which are
929 added to a chain, provided there isn't an identical one already there.
931 Argument: string of header lines
936 setup_header(const uschar *hstring)
939 int hlen = Ustrlen(hstring);
941 /* Ignore any leading newlines */
942 while (*hstring == '\n') hstring++, hlen--;
944 /* An empty string does nothing; ensure exactly one final newline. */
945 if (hlen <= 0) return;
946 if (hstring[--hlen] != '\n') /* no newline */
947 q = string_sprintf("%s\n", hstring);
948 else if (hstring[hlen-1] == '\n') /* double newline */
950 uschar * s = string_copy(hstring);
951 while(s[--hlen] == '\n')
958 /* Loop for multiple header lines, taking care about continuations */
960 for (p = q; *p != 0; )
964 int newtype = htype_add_bot;
965 header_line **hptr = &acl_added_headers;
967 /* Find next header line within the string */
971 q = Ustrchr(q, '\n'); /* we know there was a newline */
972 if (*(++q) != ' ' && *q != '\t') break;
975 /* If the line starts with a colon, interpret the instruction for where to
976 add it. This temporarily sets up a new type. */
980 if (strncmpic(p, US":after_received:", 16) == 0)
982 newtype = htype_add_rec;
985 else if (strncmpic(p, US":at_start_rfc:", 14) == 0)
987 newtype = htype_add_rfc;
990 else if (strncmpic(p, US":at_start:", 10) == 0)
992 newtype = htype_add_top;
995 else if (strncmpic(p, US":at_end:", 8) == 0)
997 newtype = htype_add_bot;
1000 while (*p == ' ' || *p == '\t') p++;
1003 /* See if this line starts with a header name, and if not, add X-ACL-Warn:
1004 to the front of it. */
1006 for (s = p; s < q - 1; s++)
1008 if (*s == ':' || !isgraph(*s)) break;
1011 hdr = string_sprintf("%s%.*s", (*s == ':')? "" : "X-ACL-Warn: ", (int) (q - p), p);
1012 hlen = Ustrlen(hdr);
1014 /* See if this line has already been added */
1016 while (*hptr != NULL)
1018 if (Ustrncmp((*hptr)->text, hdr, hlen) == 0) break;
1019 hptr = &((*hptr)->next);
1022 /* Add if not previously present */
1026 header_line *h = store_get(sizeof(header_line));
1035 /* Advance for next header line within the string */
1043 /*************************************************
1044 * List the added header lines *
1045 *************************************************/
1050 header_line * h = acl_added_headers;
1054 if (!h) return NULL;
1059 while ((cp = Ustrchr(s, '\n')) != NULL)
1061 if (cp[1] == '\0') break;
1063 /* contains embedded newline; needs doubling */
1064 g = string_catn(g, s, cp-s+1);
1065 g = string_catn(g, US"\n", 1);
1068 /* last bit of header */
1070 /*XXX could we use add_listele? */
1071 g = string_catn(g, s, cp-s+1); /* newline-sep list */
1073 while((h = h->next));
1075 g->s[g->ptr - 1] = '\0'; /* overwrite last newline */
1080 /*************************************************
1081 * Set up removed header line(s) *
1082 *************************************************/
1084 /* This function is called by the remove_header modifier. The argument is
1085 treated as a sequence of header names which are added to a colon separated
1086 list, provided there isn't an identical one already there.
1088 Argument: string of header names
1093 setup_remove_header(const uschar *hnames)
1096 acl_removed_headers = acl_removed_headers
1097 ? string_sprintf("%s : %s", acl_removed_headers, hnames)
1098 : string_copy(hnames);
1103 /*************************************************
1105 *************************************************/
1107 /* This function is called when a WARN verb's conditions are true. It adds to
1108 the message's headers, and/or writes information to the log. In each case, this
1109 only happens once (per message for headers, per connection for log).
1111 ** NOTE: The header adding action using the "message" setting is historic, and
1112 its use is now deprecated. The new add_header modifier should be used instead.
1115 where ACL_WHERE_xxxx indicating which ACL this is
1116 user_message message for adding to headers
1117 log_message message for logging, if different
1123 acl_warn(int where, uschar *user_message, uschar *log_message)
1125 if (log_message != NULL && log_message != user_message)
1128 string_item *logged;
1130 text = string_sprintf("%s Warning: %s", host_and_ident(TRUE),
1131 string_printing(log_message));
1133 /* If a sender verification has failed, and the log message is "sender verify
1134 failed", add the failure message. */
1136 if (sender_verified_failed != NULL &&
1137 sender_verified_failed->message != NULL &&
1138 strcmpic(log_message, US"sender verify failed") == 0)
1139 text = string_sprintf("%s: %s", text, sender_verified_failed->message);
1141 /* Search previously logged warnings. They are kept in malloc
1142 store so they can be freed at the start of a new message. */
1144 for (logged = acl_warn_logged; logged != NULL; logged = logged->next)
1145 if (Ustrcmp(logged->text, text) == 0) break;
1149 int length = Ustrlen(text) + 1;
1150 log_write(0, LOG_MAIN, "%s", text);
1151 logged = store_malloc(sizeof(string_item) + length);
1152 logged->text = US logged + sizeof(string_item);
1153 memcpy(logged->text, text, length);
1154 logged->next = acl_warn_logged;
1155 acl_warn_logged = logged;
1159 /* If there's no user message, we are done. */
1161 if (user_message == NULL) return;
1163 /* If this isn't a message ACL, we can't do anything with a user message.
1166 if (where > ACL_WHERE_NOTSMTP)
1168 log_write(0, LOG_MAIN|LOG_PANIC, "ACL \"warn\" with \"message\" setting "
1169 "found in a non-message (%s) ACL: cannot specify header lines here: "
1170 "message ignored", acl_wherenames[where]);
1174 /* The code for setting up header lines is now abstracted into a separate
1175 function so that it can be used for the add_header modifier as well. */
1177 setup_header(user_message);
1182 /*************************************************
1183 * Verify and check reverse DNS *
1184 *************************************************/
1186 /* Called from acl_verify() below. We look up the host name(s) of the client IP
1187 address if this has not yet been done. The host_name_lookup() function checks
1188 that one of these names resolves to an address list that contains the client IP
1189 address, so we don't actually have to do the check here.
1192 user_msgptr pointer for user message
1193 log_msgptr pointer for log message
1195 Returns: OK verification condition succeeded
1196 FAIL verification failed
1197 DEFER there was a problem verifying
1201 acl_verify_reverse(uschar **user_msgptr, uschar **log_msgptr)
1205 user_msgptr = user_msgptr; /* stop compiler warning */
1207 /* Previous success */
1209 if (sender_host_name != NULL) return OK;
1211 /* Previous failure */
1213 if (host_lookup_failed)
1215 *log_msgptr = string_sprintf("host lookup failed%s", host_lookup_msg);
1219 /* Need to do a lookup */
1222 debug_printf_indent("looking up host name to force name/address consistency check\n");
1224 if ((rc = host_name_lookup()) != OK)
1226 *log_msgptr = (rc == DEFER)?
1227 US"host lookup deferred for reverse lookup check"
1229 string_sprintf("host lookup failed for reverse lookup check%s",
1231 return rc; /* DEFER or FAIL */
1234 host_build_sender_fullhost();
1240 /*************************************************
1241 * Check client IP address matches CSA target *
1242 *************************************************/
1244 /* Called from acl_verify_csa() below. This routine scans a section of a DNS
1245 response for address records belonging to the CSA target hostname. The section
1246 is specified by the reset argument, either RESET_ADDITIONAL or RESET_ANSWERS.
1247 If one of the addresses matches the client's IP address, then the client is
1248 authorized by CSA. If there are target IP addresses but none of them match
1249 then the client is using an unauthorized IP address. If there are no target IP
1250 addresses then the client cannot be using an authorized IP address. (This is
1251 an odd configuration - why didn't the SRV record have a weight of 1 instead?)
1254 dnsa the DNS answer block
1255 dnss a DNS scan block for us to use
1256 reset option specifying what portion to scan, as described above
1257 target the target hostname to use for matching RR names
1259 Returns: CSA_OK successfully authorized
1260 CSA_FAIL_MISMATCH addresses found but none matched
1261 CSA_FAIL_NOADDR no target addresses found
1265 acl_verify_csa_address(dns_answer *dnsa, dns_scan *dnss, int reset,
1271 BOOL target_found = FALSE;
1273 for (rr = dns_next_rr(dnsa, dnss, reset);
1275 rr = dns_next_rr(dnsa, dnss, RESET_NEXT))
1277 /* Check this is an address RR for the target hostname. */
1281 && rr->type != T_AAAA
1285 if (strcmpic(target, rr->name) != 0) continue;
1287 target_found = TRUE;
1289 /* Turn the target address RR into a list of textual IP addresses and scan
1290 the list. There may be more than one if it is an A6 RR. */
1292 for (da = dns_address_from_rr(dnsa, rr); da != NULL; da = da->next)
1294 /* If the client IP address matches the target IP address, it's good! */
1296 DEBUG(D_acl) debug_printf_indent("CSA target address is %s\n", da->address);
1298 if (strcmpic(sender_host_address, da->address) == 0) return CSA_OK;
1302 /* If we found some target addresses but none of them matched, the client is
1303 using an unauthorized IP address, otherwise the target has no authorized IP
1306 if (target_found) return CSA_FAIL_MISMATCH;
1307 else return CSA_FAIL_NOADDR;
1312 /*************************************************
1313 * Verify Client SMTP Authorization *
1314 *************************************************/
1316 /* Called from acl_verify() below. This routine calls dns_lookup_special()
1317 to find the CSA SRV record corresponding to the domain argument, or
1318 $sender_helo_name if no argument is provided. It then checks that the
1319 client is authorized, and that its IP address corresponds to the SRV
1320 target's address by calling acl_verify_csa_address() above. The address
1321 should have been returned in the DNS response's ADDITIONAL section, but if
1322 not we perform another DNS lookup to get it.
1325 domain pointer to optional parameter following verify = csa
1327 Returns: CSA_UNKNOWN no valid CSA record found
1328 CSA_OK successfully authorized
1329 CSA_FAIL_* client is definitely not authorized
1330 CSA_DEFER_* there was a DNS problem
1334 acl_verify_csa(const uschar *domain)
1337 const uschar *found;
1338 int priority, weight, port;
1345 /* Work out the domain we are using for the CSA lookup. The default is the
1346 client's HELO domain. If the client has not said HELO, use its IP address
1347 instead. If it's a local client (exim -bs), CSA isn't applicable. */
1349 while (isspace(*domain) && *domain != '\0') ++domain;
1350 if (*domain == '\0') domain = sender_helo_name;
1351 if (domain == NULL) domain = sender_host_address;
1352 if (sender_host_address == NULL) return CSA_UNKNOWN;
1354 /* If we have an address literal, strip off the framing ready for turning it
1355 into a domain. The framing consists of matched square brackets possibly
1356 containing a keyword and a colon before the actual IP address. */
1358 if (domain[0] == '[')
1360 const uschar *start = Ustrchr(domain, ':');
1361 if (start == NULL) start = domain;
1362 domain = string_copyn(start + 1, Ustrlen(start) - 2);
1365 /* Turn domains that look like bare IP addresses into domains in the reverse
1366 DNS. This code also deals with address literals and $sender_host_address. It's
1367 not quite kosher to treat bare domains such as EHLO 192.0.2.57 the same as
1368 address literals, but it's probably the most friendly thing to do. This is an
1369 extension to CSA, so we allow it to be turned off for proper conformance. */
1371 if (string_is_ip_address(domain, NULL) != 0)
1373 if (!dns_csa_use_reverse) return CSA_UNKNOWN;
1374 dns_build_reverse(domain, target);
1378 /* Find out if we've already done the CSA check for this domain. If we have,
1379 return the same result again. Otherwise build a new cached result structure
1380 for this domain. The name is filled in now, and the value is filled in when
1381 we return from this function. */
1383 t = tree_search(csa_cache, domain);
1384 if (t != NULL) return t->data.val;
1386 t = store_get_perm(sizeof(tree_node) + Ustrlen(domain));
1387 Ustrcpy(t->name, domain);
1388 (void)tree_insertnode(&csa_cache, t);
1390 /* Now we are ready to do the actual DNS lookup(s). */
1393 switch (dns_special_lookup(&dnsa, domain, T_CSA, &found))
1395 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1398 return t->data.val = CSA_DEFER_SRV;
1400 /* If we found nothing, the client's authorization is unknown. */
1404 return t->data.val = CSA_UNKNOWN;
1406 /* We got something! Go on to look at the reply in more detail. */
1412 /* Scan the reply for well-formed CSA SRV records. */
1414 for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS);
1416 rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT)) if (rr->type == T_SRV)
1418 const uschar * p = rr->data;
1420 /* Extract the numerical SRV fields (p is incremented) */
1422 GETSHORT(priority, p);
1423 GETSHORT(weight, p);
1427 debug_printf_indent("CSA priority=%d weight=%d port=%d\n", priority, weight, port);
1429 /* Check the CSA version number */
1431 if (priority != 1) continue;
1433 /* If the domain does not have a CSA SRV record of its own (i.e. the domain
1434 found by dns_special_lookup() is a parent of the one we asked for), we check
1435 the subdomain assertions in the port field. At the moment there's only one
1436 assertion: legitimate SMTP clients are all explicitly authorized with CSA
1437 SRV records of their own. */
1439 if (Ustrcmp(found, domain) != 0)
1440 return t->data.val = port & 1 ? CSA_FAIL_EXPLICIT : CSA_UNKNOWN;
1442 /* This CSA SRV record refers directly to our domain, so we check the value
1443 in the weight field to work out the domain's authorization. 0 and 1 are
1444 unauthorized; 3 means the client is authorized but we can't check the IP
1445 address in order to authenticate it, so we treat it as unknown; values
1446 greater than 3 are undefined. */
1448 if (weight < 2) return t->data.val = CSA_FAIL_DOMAIN;
1450 if (weight > 2) continue;
1452 /* Weight == 2, which means the domain is authorized. We must check that the
1453 client's IP address is listed as one of the SRV target addresses. Save the
1454 target hostname then break to scan the additional data for its addresses. */
1456 (void)dn_expand(dnsa.answer, dnsa.answer + dnsa.answerlen, p,
1457 (DN_EXPAND_ARG4_TYPE)target, sizeof(target));
1459 DEBUG(D_acl) debug_printf_indent("CSA target is %s\n", target);
1464 /* If we didn't break the loop then no appropriate records were found. */
1466 if (rr == NULL) return t->data.val = CSA_UNKNOWN;
1468 /* Do not check addresses if the target is ".", in accordance with RFC 2782.
1469 A target of "." indicates there are no valid addresses, so the client cannot
1470 be authorized. (This is an odd configuration because weight=2 target=. is
1471 equivalent to weight=1, but we check for it in order to keep load off the
1472 root name servers.) Note that dn_expand() turns "." into "". */
1474 if (Ustrcmp(target, "") == 0) return t->data.val = CSA_FAIL_NOADDR;
1476 /* Scan the additional section of the CSA SRV reply for addresses belonging
1477 to the target. If the name server didn't return any additional data (e.g.
1478 because it does not fully support SRV records), we need to do another lookup
1479 to obtain the target addresses; otherwise we have a definitive result. */
1481 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ADDITIONAL, target);
1482 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1484 /* The DNS lookup type corresponds to the IP version used by the client. */
1487 if (Ustrchr(sender_host_address, ':') != NULL)
1490 #endif /* HAVE_IPV6 */
1494 lookup_dnssec_authenticated = NULL;
1495 switch (dns_lookup(&dnsa, target, type, NULL))
1497 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1500 return t->data.val = CSA_DEFER_ADDR;
1502 /* If the query succeeded, scan the addresses and return the result. */
1505 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ANSWERS, target);
1506 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1507 /* else fall through */
1509 /* If the target has no IP addresses, the client cannot have an authorized
1510 IP address. However, if the target site uses A6 records (not AAAA records)
1511 we have to do yet another lookup in order to check them. */
1515 return t->data.val = CSA_FAIL_NOADDR;
1521 /*************************************************
1522 * Handle verification (address & other) *
1523 *************************************************/
1525 enum { VERIFY_REV_HOST_LKUP, VERIFY_CERT, VERIFY_HELO, VERIFY_CSA, VERIFY_HDR_SYNTAX,
1526 VERIFY_NOT_BLIND, VERIFY_HDR_SNDR, VERIFY_SNDR, VERIFY_RCPT,
1527 VERIFY_HDR_NAMES_ASCII, VERIFY_ARC
1532 unsigned where_allowed; /* bitmap */
1533 BOOL no_options; /* Never has /option(s) following */
1534 unsigned alt_opt_sep; /* >0 Non-/ option separator (custom parser) */
1536 static verify_type_t verify_type_list[] = {
1537 /* name value where no-opt opt-sep */
1538 { US"reverse_host_lookup", VERIFY_REV_HOST_LKUP, ~0, FALSE, 0 },
1539 { US"certificate", VERIFY_CERT, ~0, TRUE, 0 },
1540 { US"helo", VERIFY_HELO, ~0, TRUE, 0 },
1541 { US"csa", VERIFY_CSA, ~0, FALSE, 0 },
1542 { US"header_syntax", VERIFY_HDR_SYNTAX, ACL_BIT_DATA | ACL_BIT_NOTSMTP, TRUE, 0 },
1543 { US"not_blind", VERIFY_NOT_BLIND, ACL_BIT_DATA | ACL_BIT_NOTSMTP, TRUE, 0 },
1544 { US"header_sender", VERIFY_HDR_SNDR, ACL_BIT_DATA | ACL_BIT_NOTSMTP, FALSE, 0 },
1545 { US"sender", VERIFY_SNDR, ACL_BIT_MAIL | ACL_BIT_RCPT
1546 |ACL_BIT_PREDATA | ACL_BIT_DATA | ACL_BIT_NOTSMTP,
1548 { US"recipient", VERIFY_RCPT, ACL_BIT_RCPT, FALSE, 0 },
1549 { US"header_names_ascii", VERIFY_HDR_NAMES_ASCII, ACL_BIT_DATA | ACL_BIT_NOTSMTP, TRUE, 0 },
1550 #ifdef EXPERIMENTAL_ARC
1551 { US"arc", VERIFY_ARC, ACL_BIT_DATA, TRUE , 0 },
1556 enum { CALLOUT_DEFER_OK, CALLOUT_NOCACHE, CALLOUT_RANDOM, CALLOUT_USE_SENDER,
1557 CALLOUT_USE_POSTMASTER, CALLOUT_POSTMASTER, CALLOUT_FULLPOSTMASTER,
1558 CALLOUT_MAILFROM, CALLOUT_POSTMASTER_MAILFROM, CALLOUT_MAXWAIT, CALLOUT_CONNECT,
1559 CALLOUT_HOLD, CALLOUT_TIME /* TIME must be last */
1565 BOOL has_option; /* Has =option(s) following */
1566 BOOL timeval; /* Has a time value */
1568 static callout_opt_t callout_opt_list[] = {
1569 /* name value flag has-opt has-time */
1570 { US"defer_ok", CALLOUT_DEFER_OK, 0, FALSE, FALSE },
1571 { US"no_cache", CALLOUT_NOCACHE, vopt_callout_no_cache, FALSE, FALSE },
1572 { US"random", CALLOUT_RANDOM, vopt_callout_random, FALSE, FALSE },
1573 { US"use_sender", CALLOUT_USE_SENDER, vopt_callout_recipsender, FALSE, FALSE },
1574 { US"use_postmaster", CALLOUT_USE_POSTMASTER,vopt_callout_recippmaster, FALSE, FALSE },
1575 { US"postmaster_mailfrom",CALLOUT_POSTMASTER_MAILFROM,0, TRUE, FALSE },
1576 { US"postmaster", CALLOUT_POSTMASTER, 0, FALSE, FALSE },
1577 { US"fullpostmaster", CALLOUT_FULLPOSTMASTER,vopt_callout_fullpm, FALSE, FALSE },
1578 { US"mailfrom", CALLOUT_MAILFROM, 0, TRUE, FALSE },
1579 { US"maxwait", CALLOUT_MAXWAIT, 0, TRUE, TRUE },
1580 { US"connect", CALLOUT_CONNECT, 0, TRUE, TRUE },
1581 { US"hold", CALLOUT_HOLD, vopt_callout_hold, FALSE, FALSE },
1582 { NULL, CALLOUT_TIME, 0, FALSE, TRUE }
1587 /* This function implements the "verify" condition. It is called when
1588 encountered in any ACL, because some tests are almost always permitted. Some
1589 just don't make sense, and always fail (for example, an attempt to test a host
1590 lookup for a non-TCP/IP message). Others are restricted to certain ACLs.
1593 where where called from
1594 addr the recipient address that the ACL is handling, or NULL
1595 arg the argument of "verify"
1596 user_msgptr pointer for user message
1597 log_msgptr pointer for log message
1598 basic_errno where to put verify errno
1600 Returns: OK verification condition succeeded
1601 FAIL verification failed
1602 DEFER there was a problem verifying
1607 acl_verify(int where, address_item *addr, const uschar *arg,
1608 uschar **user_msgptr, uschar **log_msgptr, int *basic_errno)
1612 int callout_overall = -1;
1613 int callout_connect = -1;
1614 int verify_options = 0;
1616 BOOL verify_header_sender = FALSE;
1617 BOOL defer_ok = FALSE;
1618 BOOL callout_defer_ok = FALSE;
1619 BOOL no_details = FALSE;
1620 BOOL success_on_redirect = FALSE;
1621 address_item *sender_vaddr = NULL;
1622 uschar *verify_sender_address = NULL;
1623 uschar *pm_mailfrom = NULL;
1624 uschar *se_mailfrom = NULL;
1626 /* Some of the verify items have slash-separated options; some do not. Diagnose
1627 an error if options are given for items that don't expect them.
1630 uschar *slash = Ustrchr(arg, '/');
1631 const uschar *list = arg;
1632 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
1635 if (!ss) goto BAD_VERIFY;
1637 /* Handle name/address consistency verification in a separate function. */
1639 for (vp= verify_type_list;
1640 CS vp < CS verify_type_list + sizeof(verify_type_list);
1643 if (vp->alt_opt_sep ? strncmpic(ss, vp->name, vp->alt_opt_sep) == 0
1644 : strcmpic (ss, vp->name) == 0)
1646 if (CS vp >= CS verify_type_list + sizeof(verify_type_list))
1649 if (vp->no_options && slash)
1651 *log_msgptr = string_sprintf("unexpected '/' found in \"%s\" "
1652 "(this verify item has no options)", arg);
1655 if (!(vp->where_allowed & BIT(where)))
1657 *log_msgptr = string_sprintf("cannot verify %s in ACL for %s",
1658 vp->name, acl_wherenames[where]);
1663 case VERIFY_REV_HOST_LKUP:
1664 if (sender_host_address == NULL) return OK;
1665 if ((rc = acl_verify_reverse(user_msgptr, log_msgptr)) == DEFER)
1666 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size)))
1667 if (strcmpic(ss, US"defer_ok") == 0)
1672 /* TLS certificate verification is done at STARTTLS time; here we just
1673 test whether it was successful or not. (This is for optional verification; for
1674 mandatory verification, the connection doesn't last this long.) */
1676 if (tls_in.certificate_verified) return OK;
1677 *user_msgptr = US"no verified certificate";
1681 /* We can test the result of optional HELO verification that might have
1682 occurred earlier. If not, we can attempt the verification now. */
1684 if (!helo_verified && !helo_verify_failed) smtp_verify_helo();
1685 return helo_verified? OK : FAIL;
1688 /* Do Client SMTP Authorization checks in a separate function, and turn the
1689 result code into user-friendly strings. */
1691 rc = acl_verify_csa(list);
1692 *log_msgptr = *user_msgptr = string_sprintf("client SMTP authorization %s",
1693 csa_reason_string[rc]);
1694 csa_status = csa_status_string[rc];
1695 DEBUG(D_acl) debug_printf_indent("CSA result %s\n", csa_status);
1696 return csa_return_code[rc];
1698 case VERIFY_HDR_SYNTAX:
1699 /* Check that all relevant header lines have the correct 5322-syntax. If there is
1700 a syntax error, we return details of the error to the sender if configured to
1701 send out full details. (But a "message" setting on the ACL can override, as
1704 rc = verify_check_headers(log_msgptr);
1705 if (rc != OK && *log_msgptr)
1706 if (smtp_return_error_details)
1707 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1709 acl_verify_message = *log_msgptr;
1712 case VERIFY_HDR_NAMES_ASCII:
1713 /* Check that all header names are true 7 bit strings
1714 See RFC 5322, 2.2. and RFC 6532, 3. */
1716 rc = verify_check_header_names_ascii(log_msgptr);
1717 if (rc != OK && smtp_return_error_details && *log_msgptr != NULL)
1718 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1721 case VERIFY_NOT_BLIND:
1722 /* Check that no recipient of this message is "blind", that is, every envelope
1723 recipient must be mentioned in either To: or Cc:. */
1725 rc = verify_check_notblind();
1728 *log_msgptr = string_sprintf("bcc recipient detected");
1729 if (smtp_return_error_details)
1730 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1734 /* The remaining verification tests check recipient and sender addresses,
1735 either from the envelope or from the header. There are a number of
1736 slash-separated options that are common to all of them. */
1738 case VERIFY_HDR_SNDR:
1739 verify_header_sender = TRUE;
1743 /* In the case of a sender, this can optionally be followed by an address to use
1744 in place of the actual sender (rare special-case requirement). */
1748 verify_sender_address = sender_address;
1751 while (isspace(*s)) s++;
1752 if (*s++ != '=') goto BAD_VERIFY;
1753 while (isspace(*s)) s++;
1754 verify_sender_address = string_copy(s);
1765 /* Remaining items are optional; they apply to sender and recipient
1766 verification, including "header sender" verification. */
1768 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size))
1771 if (strcmpic(ss, US"defer_ok") == 0) defer_ok = TRUE;
1772 else if (strcmpic(ss, US"no_details") == 0) no_details = TRUE;
1773 else if (strcmpic(ss, US"success_on_redirect") == 0) success_on_redirect = TRUE;
1775 /* These two old options are left for backwards compatibility */
1777 else if (strcmpic(ss, US"callout_defer_ok") == 0)
1779 callout_defer_ok = TRUE;
1780 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1783 else if (strcmpic(ss, US"check_postmaster") == 0)
1786 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1789 /* The callout option has a number of sub-options, comma separated */
1791 else if (strncmpic(ss, US"callout", 7) == 0)
1793 callout = CALLOUT_TIMEOUT_DEFAULT;
1797 while (isspace(*ss)) ss++;
1800 const uschar * sublist = ss;
1804 while (isspace(*sublist)) sublist++;
1806 while ((opt = string_nextinlist(&sublist, &optsep, buffer, sizeof(buffer))))
1809 double period = 1.0F;
1811 for (op= callout_opt_list; op->name; op++)
1812 if (strncmpic(opt, op->name, Ustrlen(op->name)) == 0)
1815 verify_options |= op->flag;
1818 opt += Ustrlen(op->name);
1819 while (isspace(*opt)) opt++;
1822 *log_msgptr = string_sprintf("'=' expected after "
1823 "\"%s\" in ACL verify condition \"%s\"", op->name, arg);
1826 while (isspace(*opt)) opt++;
1828 if (op->timeval && (period = readconf_readtime(opt, 0, FALSE)) < 0)
1830 *log_msgptr = string_sprintf("bad time value in ACL condition "
1831 "\"verify %s\"", arg);
1837 case CALLOUT_DEFER_OK: callout_defer_ok = TRUE; break;
1838 case CALLOUT_POSTMASTER: pm_mailfrom = US""; break;
1839 case CALLOUT_FULLPOSTMASTER: pm_mailfrom = US""; break;
1840 case CALLOUT_MAILFROM:
1841 if (!verify_header_sender)
1843 *log_msgptr = string_sprintf("\"mailfrom\" is allowed as a "
1844 "callout option only for verify=header_sender (detected in ACL "
1845 "condition \"%s\")", arg);
1848 se_mailfrom = string_copy(opt);
1850 case CALLOUT_POSTMASTER_MAILFROM: pm_mailfrom = string_copy(opt); break;
1851 case CALLOUT_MAXWAIT: callout_overall = period; break;
1852 case CALLOUT_CONNECT: callout_connect = period; break;
1853 case CALLOUT_TIME: callout = period; break;
1859 *log_msgptr = string_sprintf("'=' expected after \"callout\" in "
1860 "ACL condition \"%s\"", arg);
1866 /* Option not recognized */
1870 *log_msgptr = string_sprintf("unknown option \"%s\" in ACL "
1871 "condition \"verify %s\"", ss, arg);
1876 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster)) ==
1877 (vopt_callout_recipsender|vopt_callout_recippmaster))
1879 *log_msgptr = US"only one of use_sender and use_postmaster can be set "
1880 "for a recipient callout";
1884 /* Handle sender-in-header verification. Default the user message to the log
1885 message if giving out verification details. */
1887 if (verify_header_sender)
1891 if ((rc = verify_check_header_address(user_msgptr, log_msgptr, callout,
1892 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, verify_options,
1895 *basic_errno = verrno;
1896 if (smtp_return_error_details)
1898 if (!*user_msgptr && *log_msgptr)
1899 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1900 if (rc == DEFER) acl_temp_details = TRUE;
1905 /* Handle a sender address. The default is to verify *the* sender address, but
1906 optionally a different address can be given, for special requirements. If the
1907 address is empty, we are dealing with a bounce message that has no sender, so
1908 we cannot do any checking. If the real sender address gets rewritten during
1909 verification (e.g. DNS widening), set the flag to stop it being rewritten again
1910 during message reception.
1912 A list of verified "sender" addresses is kept to try to avoid doing to much
1913 work repetitively when there are multiple recipients in a message and they all
1914 require sender verification. However, when callouts are involved, it gets too
1915 complicated because different recipients may require different callout options.
1916 Therefore, we always do a full sender verify when any kind of callout is
1917 specified. Caching elsewhere, for instance in the DNS resolver and in the
1918 callout handling, should ensure that this is not terribly inefficient. */
1920 else if (verify_sender_address)
1922 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster)))
1924 *log_msgptr = US"use_sender or use_postmaster cannot be used for a "
1925 "sender verify callout";
1929 sender_vaddr = verify_checked_sender(verify_sender_address);
1930 if (sender_vaddr != NULL && /* Previously checked */
1931 callout <= 0) /* No callout needed this time */
1933 /* If the "routed" flag is set, it means that routing worked before, so
1934 this check can give OK (the saved return code value, if set, belongs to a
1935 callout that was done previously). If the "routed" flag is not set, routing
1936 must have failed, so we use the saved return code. */
1938 if (testflag(sender_vaddr, af_verify_routed))
1942 rc = sender_vaddr->special_action;
1943 *basic_errno = sender_vaddr->basic_errno;
1945 HDEBUG(D_acl) debug_printf_indent("using cached sender verify result\n");
1948 /* Do a new verification, and cache the result. The cache is used to avoid
1949 verifying the sender multiple times for multiple RCPTs when callouts are not
1950 specified (see comments above).
1952 The cache is also used on failure to give details in response to the first
1953 RCPT that gets bounced for this reason. However, this can be suppressed by
1954 the no_details option, which sets the flag that says "this detail has already
1955 been sent". The cache normally contains just one address, but there may be
1956 more in esoteric circumstances. */
1961 uschar *save_address_data = deliver_address_data;
1963 sender_vaddr = deliver_make_addr(verify_sender_address, TRUE);
1965 if ((sender_vaddr->prop.utf8_msg = message_smtputf8))
1967 sender_vaddr->prop.utf8_downcvt = message_utf8_downconvert == 1;
1968 sender_vaddr->prop.utf8_downcvt_maybe = message_utf8_downconvert == -1;
1971 if (no_details) setflag(sender_vaddr, af_sverify_told);
1972 if (verify_sender_address[0] != 0)
1974 /* If this is the real sender address, save the unrewritten version
1975 for use later in receive. Otherwise, set a flag so that rewriting the
1976 sender in verify_address() does not update sender_address. */
1978 if (verify_sender_address == sender_address)
1979 sender_address_unrewritten = sender_address;
1981 verify_options |= vopt_fake_sender;
1983 if (success_on_redirect)
1984 verify_options |= vopt_success_on_redirect;
1986 /* The recipient, qualify, and expn options are never set in
1989 rc = verify_address(sender_vaddr, NULL, verify_options, callout,
1990 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, &routed);
1992 HDEBUG(D_acl) debug_printf_indent("----------- end verify ------------\n");
1995 *basic_errno = sender_vaddr->basic_errno;
1999 if (Ustrcmp(sender_vaddr->address, verify_sender_address) != 0)
2000 debug_printf_indent("sender %s verified ok as %s\n",
2001 verify_sender_address, sender_vaddr->address);
2003 debug_printf_indent("sender %s verified ok\n",
2004 verify_sender_address);
2008 rc = OK; /* Null sender */
2010 /* Cache the result code */
2012 if (routed) setflag(sender_vaddr, af_verify_routed);
2013 if (callout > 0) setflag(sender_vaddr, af_verify_callout);
2014 sender_vaddr->special_action = rc;
2015 sender_vaddr->next = sender_verified_list;
2016 sender_verified_list = sender_vaddr;
2018 /* Restore the recipient address data, which might have been clobbered by
2019 the sender verification. */
2021 deliver_address_data = save_address_data;
2024 /* Put the sender address_data value into $sender_address_data */
2026 sender_address_data = sender_vaddr->prop.address_data;
2029 /* A recipient address just gets a straightforward verify; again we must handle
2030 the DEFER overrides. */
2036 if (success_on_redirect)
2037 verify_options |= vopt_success_on_redirect;
2039 /* We must use a copy of the address for verification, because it might
2043 rc = verify_address(&addr2, NULL, verify_options|vopt_is_recipient, callout,
2044 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, NULL);
2045 HDEBUG(D_acl) debug_printf_indent("----------- end verify ------------\n");
2047 *basic_errno = addr2.basic_errno;
2048 *log_msgptr = addr2.message;
2049 *user_msgptr = (addr2.user_message != NULL)?
2050 addr2.user_message : addr2.message;
2052 /* Allow details for temporary error if the address is so flagged. */
2053 if (testflag((&addr2), af_pass_message)) acl_temp_details = TRUE;
2055 /* Make $address_data visible */
2056 deliver_address_data = addr2.prop.address_data;
2059 /* We have a result from the relevant test. Handle defer overrides first. */
2061 if (rc == DEFER && (defer_ok ||
2062 (callout_defer_ok && *basic_errno == ERRNO_CALLOUTDEFER)))
2064 HDEBUG(D_acl) debug_printf_indent("verify defer overridden by %s\n",
2065 defer_ok? "defer_ok" : "callout_defer_ok");
2069 /* If we've failed a sender, set up a recipient message, and point
2070 sender_verified_failed to the address item that actually failed. */
2072 if (rc != OK && verify_sender_address != NULL)
2075 *log_msgptr = *user_msgptr = US"Sender verify failed";
2076 else if (*basic_errno != ERRNO_CALLOUTDEFER)
2077 *log_msgptr = *user_msgptr = US"Could not complete sender verify";
2080 *log_msgptr = US"Could not complete sender verify callout";
2081 *user_msgptr = smtp_return_error_details? sender_vaddr->user_message :
2085 sender_verified_failed = sender_vaddr;
2088 /* Verifying an address messes up the values of $domain and $local_part,
2089 so reset them before returning if this is a RCPT ACL. */
2093 deliver_domain = addr->domain;
2094 deliver_localpart = addr->local_part;
2098 /* Syntax errors in the verify argument come here. */
2101 *log_msgptr = string_sprintf("expected \"sender[=address]\", \"recipient\", "
2102 "\"helo\", \"header_syntax\", \"header_sender\", \"header_names_ascii\" "
2103 "or \"reverse_host_lookup\" at start of ACL condition "
2104 "\"verify %s\"", arg);
2111 /*************************************************
2112 * Check argument for control= modifier *
2113 *************************************************/
2115 /* Called from acl_check_condition() below
2118 arg the argument string for control=
2119 pptr set to point to the terminating character
2120 where which ACL we are in
2121 log_msgptr for error messages
2123 Returns: CONTROL_xxx value
2127 decode_control(const uschar *arg, const uschar **pptr, int where, uschar **log_msgptr)
2132 if ( (idx = find_control(arg, controls_list, nelem(controls_list))) < 0
2133 || ( arg[len = Ustrlen((d = controls_list+idx)->name)] != 0
2134 && (!d->has_option || arg[len] != '/')
2137 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
2138 return CONTROL_ERROR;
2148 /*************************************************
2149 * Return a ratelimit error *
2150 *************************************************/
2152 /* Called from acl_ratelimit() below
2155 log_msgptr for error messages
2156 format format string
2157 ... supplementary arguments
2158 ss ratelimit option name
2159 where ACL_WHERE_xxxx indicating which ACL this is
2165 ratelimit_error(uschar **log_msgptr, const char *format, ...)
2168 uschar buffer[STRING_SPRINTF_BUFFER_SIZE];
2169 va_start(ap, format);
2170 if (!string_vformat(buffer, sizeof(buffer), format, ap))
2171 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
2172 "string_sprintf expansion was longer than " SIZE_T_FMT, sizeof(buffer));
2174 *log_msgptr = string_sprintf(
2175 "error in arguments to \"ratelimit\" condition: %s", buffer);
2182 /*************************************************
2183 * Handle rate limiting *
2184 *************************************************/
2186 /* Called by acl_check_condition() below to calculate the result
2187 of the ACL ratelimit condition.
2189 Note that the return value might be slightly unexpected: if the
2190 sender's rate is above the limit then the result is OK. This is
2191 similar to the dnslists condition, and is so that you can write
2192 ACL clauses like: defer ratelimit = 15 / 1h
2195 arg the option string for ratelimit=
2196 where ACL_WHERE_xxxx indicating which ACL this is
2197 log_msgptr for error messages
2199 Returns: OK - Sender's rate is above limit
2200 FAIL - Sender's rate is below limit
2201 DEFER - Problem opening ratelimit database
2202 ERROR - Syntax error in options.
2206 acl_ratelimit(const uschar *arg, int where, uschar **log_msgptr)
2208 double limit, period, count;
2211 uschar *unique = NULL;
2213 BOOL leaky = FALSE, strict = FALSE, readonly = FALSE;
2214 BOOL noupdate = FALSE, badacl = FALSE;
2215 int mode = RATE_PER_WHAT;
2217 tree_node **anchor, *t;
2218 open_db dbblock, *dbm;
2220 dbdata_ratelimit *dbd;
2221 dbdata_ratelimit_unique *dbdb;
2224 /* Parse the first two options and record their values in expansion
2225 variables. These variables allow the configuration to have informative
2226 error messages based on rate limits obtained from a table lookup. */
2228 /* First is the maximum number of messages per period / maximum burst
2229 size, which must be greater than or equal to zero. Zero is useful for
2230 rate measurement as opposed to rate limiting. */
2232 sender_rate_limit = string_nextinlist(&arg, &sep, NULL, 0);
2233 if (sender_rate_limit == NULL)
2234 return ratelimit_error(log_msgptr, "sender rate limit not set");
2236 limit = Ustrtod(sender_rate_limit, &ss);
2237 if (tolower(*ss) == 'k') { limit *= 1024.0; ss++; }
2238 else if (tolower(*ss) == 'm') { limit *= 1024.0*1024.0; ss++; }
2239 else if (tolower(*ss) == 'g') { limit *= 1024.0*1024.0*1024.0; ss++; }
2241 if (limit < 0.0 || *ss != '\0')
2242 return ratelimit_error(log_msgptr,
2243 "\"%s\" is not a positive number", sender_rate_limit);
2245 /* Second is the rate measurement period / exponential smoothing time
2246 constant. This must be strictly greater than zero, because zero leads to
2247 run-time division errors. */
2249 sender_rate_period = string_nextinlist(&arg, &sep, NULL, 0);
2250 if (sender_rate_period == NULL) period = -1.0;
2251 else period = readconf_readtime(sender_rate_period, 0, FALSE);
2253 return ratelimit_error(log_msgptr,
2254 "\"%s\" is not a time value", sender_rate_period);
2256 /* By default we are counting one of something, but the per_rcpt,
2257 per_byte, and count options can change this. */
2261 /* Parse the other options. */
2263 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2266 if (strcmpic(ss, US"leaky") == 0) leaky = TRUE;
2267 else if (strcmpic(ss, US"strict") == 0) strict = TRUE;
2268 else if (strcmpic(ss, US"noupdate") == 0) noupdate = TRUE;
2269 else if (strcmpic(ss, US"readonly") == 0) readonly = TRUE;
2270 else if (strcmpic(ss, US"per_cmd") == 0) RATE_SET(mode, PER_CMD);
2271 else if (strcmpic(ss, US"per_conn") == 0)
2273 RATE_SET(mode, PER_CONN);
2274 if (where == ACL_WHERE_NOTSMTP || where == ACL_WHERE_NOTSMTP_START)
2277 else if (strcmpic(ss, US"per_mail") == 0)
2279 RATE_SET(mode, PER_MAIL);
2280 if (where > ACL_WHERE_NOTSMTP) badacl = TRUE;
2282 else if (strcmpic(ss, US"per_rcpt") == 0)
2284 /* If we are running in the RCPT ACL, then we'll count the recipients
2285 one by one, but if we are running when we have accumulated the whole
2286 list then we'll add them all in one batch. */
2287 if (where == ACL_WHERE_RCPT)
2288 RATE_SET(mode, PER_RCPT);
2289 else if (where >= ACL_WHERE_PREDATA && where <= ACL_WHERE_NOTSMTP)
2290 RATE_SET(mode, PER_ALLRCPTS), count = (double)recipients_count;
2291 else if (where == ACL_WHERE_MAIL || where > ACL_WHERE_NOTSMTP)
2292 RATE_SET(mode, PER_RCPT), badacl = TRUE;
2294 else if (strcmpic(ss, US"per_byte") == 0)
2296 /* If we have not yet received the message data and there was no SIZE
2297 declaration on the MAIL command, then it's safe to just use a value of
2298 zero and let the recorded rate decay as if nothing happened. */
2299 RATE_SET(mode, PER_MAIL);
2300 if (where > ACL_WHERE_NOTSMTP) badacl = TRUE;
2301 else count = message_size < 0 ? 0.0 : (double)message_size;
2303 else if (strcmpic(ss, US"per_addr") == 0)
2305 RATE_SET(mode, PER_RCPT);
2306 if (where != ACL_WHERE_RCPT) badacl = TRUE, unique = US"*";
2307 else unique = string_sprintf("%s@%s", deliver_localpart, deliver_domain);
2309 else if (strncmpic(ss, US"count=", 6) == 0)
2312 count = Ustrtod(ss+6, &e);
2313 if (count < 0.0 || *e != '\0')
2314 return ratelimit_error(log_msgptr,
2315 "\"%s\" is not a positive number", ss);
2317 else if (strncmpic(ss, US"unique=", 7) == 0)
2318 unique = string_copy(ss + 7);
2319 else if (key == NULL)
2320 key = string_copy(ss);
2322 key = string_sprintf("%s/%s", key, ss);
2325 /* Sanity check. When the badacl flag is set the update mode must either
2326 be readonly (which is the default if it is omitted) or, for backwards
2327 compatibility, a combination of noupdate and strict or leaky. */
2329 if (mode == RATE_PER_CLASH)
2330 return ratelimit_error(log_msgptr, "conflicting per_* options");
2331 if (leaky + strict + readonly > 1)
2332 return ratelimit_error(log_msgptr, "conflicting update modes");
2333 if (badacl && (leaky || strict) && !noupdate)
2334 return ratelimit_error(log_msgptr,
2335 "\"%s\" must not have /leaky or /strict option in %s ACL",
2336 ratelimit_option_string[mode], acl_wherenames[where]);
2338 /* Set the default values of any unset options. In readonly mode we
2339 perform the rate computation without any increment so that its value
2340 decays to eventually allow over-limit senders through. */
2342 if (noupdate) readonly = TRUE, leaky = strict = FALSE;
2343 if (badacl) readonly = TRUE;
2344 if (readonly) count = 0.0;
2345 if (!strict && !readonly) leaky = TRUE;
2346 if (mode == RATE_PER_WHAT) mode = RATE_PER_MAIL;
2348 /* Create the lookup key. If there is no explicit key, use sender_host_address.
2349 If there is no sender_host_address (e.g. -bs or acl_not_smtp) then we simply
2350 omit it. The smoothing constant (sender_rate_period) and the per_xxx options
2351 are added to the key because they alter the meaning of the stored data. */
2354 key = (sender_host_address == NULL)? US"" : sender_host_address;
2356 key = string_sprintf("%s/%s/%s%s",
2358 ratelimit_option_string[mode],
2359 unique == NULL ? "" : "unique/",
2363 debug_printf_indent("ratelimit condition count=%.0f %.1f/%s\n", count, limit, key);
2365 /* See if we have already computed the rate by looking in the relevant tree.
2366 For per-connection rate limiting, store tree nodes and dbdata in the permanent
2367 pool so that they survive across resets. In readonly mode we only remember the
2368 result for the rest of this command in case a later command changes it. After
2369 this bit of logic the code is independent of the per_* mode. */
2371 old_pool = store_pool;
2374 anchor = &ratelimiters_cmd;
2377 anchor = &ratelimiters_conn;
2378 store_pool = POOL_PERM;
2382 case RATE_PER_ALLRCPTS:
2383 anchor = &ratelimiters_mail;
2388 anchor = &ratelimiters_cmd;
2391 anchor = NULL; /* silence an "unused" complaint */
2392 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
2393 "internal ACL error: unknown ratelimit mode %d", mode);
2397 t = tree_search(*anchor, key);
2401 /* The following few lines duplicate some of the code below. */
2402 rc = (dbd->rate < limit)? FAIL : OK;
2403 store_pool = old_pool;
2404 sender_rate = string_sprintf("%.1f", dbd->rate);
2406 debug_printf_indent("ratelimit found pre-computed rate %s\n", sender_rate);
2410 /* We aren't using a pre-computed rate, so get a previously recorded rate
2411 from the database, which will be updated and written back if required. */
2413 if (!(dbm = dbfn_open(US"ratelimit", O_RDWR, &dbblock, TRUE)))
2415 store_pool = old_pool;
2417 HDEBUG(D_acl) debug_printf_indent("ratelimit database not available\n");
2418 *log_msgptr = US"ratelimit database not available";
2421 dbdb = dbfn_read_with_length(dbm, key, &dbdb_size);
2424 gettimeofday(&tv, NULL);
2428 /* Locate the basic ratelimit block inside the DB data. */
2429 HDEBUG(D_acl) debug_printf_indent("ratelimit found key in database\n");
2432 /* Forget the old Bloom filter if it is too old, so that we count each
2433 repeating event once per period. We don't simply clear and re-use the old
2434 filter because we want its size to change if the limit changes. Note that
2435 we keep the dbd pointer for copying the rate into the new data block. */
2437 if(unique != NULL && tv.tv_sec > dbdb->bloom_epoch + period)
2439 HDEBUG(D_acl) debug_printf_indent("ratelimit discarding old Bloom filter\n");
2445 if(unique != NULL && dbdb_size < sizeof(*dbdb))
2447 HDEBUG(D_acl) debug_printf_indent("ratelimit discarding undersize Bloom filter\n");
2452 /* Allocate a new data block if the database lookup failed
2453 or the Bloom filter passed its age limit. */
2459 /* No Bloom filter. This basic ratelimit block is initialized below. */
2460 HDEBUG(D_acl) debug_printf_indent("ratelimit creating new rate data block\n");
2461 dbdb_size = sizeof(*dbd);
2462 dbdb = store_get(dbdb_size);
2467 HDEBUG(D_acl) debug_printf_indent("ratelimit creating new Bloom filter\n");
2469 /* See the long comment below for an explanation of the magic number 2.
2470 The filter has a minimum size in case the rate limit is very small;
2471 this is determined by the definition of dbdata_ratelimit_unique. */
2473 extra = (int)limit * 2 - sizeof(dbdb->bloom);
2474 if (extra < 0) extra = 0;
2475 dbdb_size = sizeof(*dbdb) + extra;
2476 dbdb = store_get(dbdb_size);
2477 dbdb->bloom_epoch = tv.tv_sec;
2478 dbdb->bloom_size = sizeof(dbdb->bloom) + extra;
2479 memset(dbdb->bloom, 0, dbdb->bloom_size);
2481 /* Preserve any basic ratelimit data (which is our longer-term memory)
2482 by copying it from the discarded block. */
2492 /* If we are counting unique events, find out if this event is new or not.
2493 If the client repeats the event during the current period then it should be
2494 counted. We skip this code in readonly mode for efficiency, because any
2495 changes to the filter will be discarded and because count is already set to
2498 if (unique != NULL && !readonly)
2500 /* We identify unique events using a Bloom filter. (You can find my
2501 notes on Bloom filters at http://fanf.livejournal.com/81696.html)
2502 With the per_addr option, an "event" is a recipient address, though the
2503 user can use the unique option to define their own events. We only count
2504 an event if we have not seen it before.
2506 We size the filter according to the rate limit, which (in leaky mode)
2507 is the limit on the population of the filter. We allow 16 bits of space
2508 per entry (see the construction code above) and we set (up to) 8 of them
2509 when inserting an element (see the loop below). The probability of a false
2510 positive (an event we have not seen before but which we fail to count) is
2514 allzero = exp(-numhash * pop / size)
2515 = exp(-0.5 * pop / limit)
2516 fpr = pow(1 - allzero, numhash)
2518 For senders at the limit the fpr is 0.06% or 1 in 1700
2519 and for senders at half the limit it is 0.0006% or 1 in 170000
2521 In strict mode the Bloom filter can fill up beyond the normal limit, in
2522 which case the false positive rate will rise. This means that the
2523 measured rate for very fast senders can bogusly drop off after a while.
2525 At twice the limit, the fpr is 2.5% or 1 in 40
2526 At four times the limit, it is 31% or 1 in 3.2
2528 It takes ln(pop/limit) periods for an over-limit burst of pop events to
2529 decay below the limit, and if this is more than one then the Bloom filter
2530 will be discarded before the decay gets that far. The false positive rate
2531 at this threshold is 9.3% or 1 in 10.7. */
2534 unsigned n, hash, hinc;
2538 /* Instead of using eight independent hash values, we combine two values
2539 using the formula h1 + n * h2. This does not harm the Bloom filter's
2540 performance, and means the amount of hash we need is independent of the
2541 number of bits we set in the filter. */
2543 md5_start(&md5info);
2544 md5_end(&md5info, unique, Ustrlen(unique), md5sum);
2545 hash = md5sum[0] | md5sum[1] << 8 | md5sum[2] << 16 | md5sum[3] << 24;
2546 hinc = md5sum[4] | md5sum[5] << 8 | md5sum[6] << 16 | md5sum[7] << 24;
2548 /* Scan the bits corresponding to this event. A zero bit means we have
2549 not seen it before. Ensure all bits are set to record this event. */
2551 HDEBUG(D_acl) debug_printf_indent("ratelimit checking uniqueness of %s\n", unique);
2554 for (n = 0; n < 8; n++, hash += hinc)
2556 int bit = 1 << (hash % 8);
2557 int byte = (hash / 8) % dbdb->bloom_size;
2558 if ((dbdb->bloom[byte] & bit) == 0)
2560 dbdb->bloom[byte] |= bit;
2565 /* If this event has occurred before, do not count it. */
2569 HDEBUG(D_acl) debug_printf_indent("ratelimit event found in Bloom filter\n");
2573 HDEBUG(D_acl) debug_printf_indent("ratelimit event added to Bloom filter\n");
2576 /* If there was no previous ratelimit data block for this key, initialize
2577 the new one, otherwise update the block from the database. The initial rate
2578 is what would be computed by the code below for an infinite interval. */
2582 HDEBUG(D_acl) debug_printf_indent("ratelimit initializing new key's rate data\n");
2584 dbd->time_stamp = tv.tv_sec;
2585 dbd->time_usec = tv.tv_usec;
2590 /* The smoothed rate is computed using an exponentially weighted moving
2591 average adjusted for variable sampling intervals. The standard EWMA for
2592 a fixed sampling interval is: f'(t) = (1 - a) * f(t) + a * f'(t - 1)
2593 where f() is the measured value and f'() is the smoothed value.
2595 Old data decays out of the smoothed value exponentially, such that data n
2596 samples old is multiplied by a^n. The exponential decay time constant p
2597 is defined such that data p samples old is multiplied by 1/e, which means
2598 that a = exp(-1/p). We can maintain the same time constant for a variable
2599 sampling interval i by using a = exp(-i/p).
2601 The rate we are measuring is messages per period, suitable for directly
2602 comparing with the limit. The average rate between now and the previous
2603 message is period / interval, which we feed into the EWMA as the sample.
2605 It turns out that the number of messages required for the smoothed rate
2606 to reach the limit when they are sent in a burst is equal to the limit.
2607 This can be seen by analysing the value of the smoothed rate after N
2608 messages sent at even intervals. Let k = (1 - a) * p/i
2610 rate_1 = (1 - a) * p/i + a * rate_0
2612 rate_2 = k + a * rate_1
2613 = k + a * k + a^2 * rate_0
2614 rate_3 = k + a * k + a^2 * k + a^3 * rate_0
2615 rate_N = rate_0 * a^N + k * SUM(x=0..N-1)(a^x)
2616 = rate_0 * a^N + k * (1 - a^N) / (1 - a)
2617 = rate_0 * a^N + p/i * (1 - a^N)
2619 When N is large, a^N -> 0 so rate_N -> p/i as desired.
2621 rate_N = p/i + (rate_0 - p/i) * a^N
2622 a^N = (rate_N - p/i) / (rate_0 - p/i)
2623 N * -i/p = log((rate_N - p/i) / (rate_0 - p/i))
2624 N = p/i * log((rate_0 - p/i) / (rate_N - p/i))
2626 Numerical analysis of the above equation, setting the computed rate to
2627 increase from rate_0 = 0 to rate_N = limit, shows that for large sending
2628 rates, p/i, the number of messages N = limit. So limit serves as both the
2629 maximum rate measured in messages per period, and the maximum number of
2630 messages that can be sent in a fast burst. */
2632 double this_time = (double)tv.tv_sec
2633 + (double)tv.tv_usec / 1000000.0;
2634 double prev_time = (double)dbd->time_stamp
2635 + (double)dbd->time_usec / 1000000.0;
2637 /* We must avoid division by zero, and deal gracefully with the clock going
2638 backwards. If we blunder ahead when time is in reverse then the computed
2639 rate will be bogus. To be safe we clamp interval to a very small number. */
2641 double interval = this_time - prev_time <= 0.0 ? 1e-9
2642 : this_time - prev_time;
2644 double i_over_p = interval / period;
2645 double a = exp(-i_over_p);
2647 /* Combine the instantaneous rate (period / interval) with the previous rate
2648 using the smoothing factor a. In order to measure sized events, multiply the
2649 instantaneous rate by the count of bytes or recipients etc. */
2651 dbd->time_stamp = tv.tv_sec;
2652 dbd->time_usec = tv.tv_usec;
2653 dbd->rate = (1 - a) * count / i_over_p + a * dbd->rate;
2655 /* When events are very widely spaced the computed rate tends towards zero.
2656 Although this is accurate it turns out not to be useful for our purposes,
2657 especially when the first event after a long silence is the start of a spam
2658 run. A more useful model is that the rate for an isolated event should be the
2659 size of the event per the period size, ignoring the lack of events outside
2660 the current period and regardless of where the event falls in the period. So,
2661 if the interval was so long that the calculated rate is unhelpfully small, we
2662 re-initialize the rate. In the absence of higher-rate bursts, the condition
2663 below is true if the interval is greater than the period. */
2665 if (dbd->rate < count) dbd->rate = count;
2668 /* Clients sending at the limit are considered to be over the limit.
2669 This matters for edge cases such as a limit of zero, when the client
2670 should be completely blocked. */
2672 rc = (dbd->rate < limit)? FAIL : OK;
2674 /* Update the state if the rate is low or if we are being strict. If we
2675 are in leaky mode and the sender's rate is too high, we do not update
2676 the recorded rate in order to avoid an over-aggressive sender's retry
2677 rate preventing them from getting any email through. If readonly is set,
2678 neither leaky nor strict are set, so we do not do any updates. */
2680 if ((rc == FAIL && leaky) || strict)
2682 dbfn_write(dbm, key, dbdb, dbdb_size);
2683 HDEBUG(D_acl) debug_printf_indent("ratelimit db updated\n");
2687 HDEBUG(D_acl) debug_printf_indent("ratelimit db not updated: %s\n",
2688 readonly? "readonly mode" : "over the limit, but leaky");
2693 /* Store the result in the tree for future reference. */
2695 t = store_get(sizeof(tree_node) + Ustrlen(key));
2697 Ustrcpy(t->name, key);
2698 (void)tree_insertnode(anchor, t);
2700 /* We create the formatted version of the sender's rate very late in
2701 order to ensure that it is done using the correct storage pool. */
2703 store_pool = old_pool;
2704 sender_rate = string_sprintf("%.1f", dbd->rate);
2707 debug_printf_indent("ratelimit computed rate %s\n", sender_rate);
2714 /*************************************************
2715 * The udpsend ACL modifier *
2716 *************************************************/
2718 /* Called by acl_check_condition() below.
2721 arg the option string for udpsend=
2722 log_msgptr for error messages
2724 Returns: OK - Completed.
2725 DEFER - Problem with DNS lookup.
2726 ERROR - Syntax error in options.
2730 acl_udpsend(const uschar *arg, uschar **log_msgptr)
2742 hostname = string_nextinlist(&arg, &sep, NULL, 0);
2743 portstr = string_nextinlist(&arg, &sep, NULL, 0);
2747 *log_msgptr = US"missing destination host in \"udpsend\" modifier";
2752 *log_msgptr = US"missing destination port in \"udpsend\" modifier";
2757 *log_msgptr = US"missing datagram payload in \"udpsend\" modifier";
2760 portnum = Ustrtol(portstr, &portend, 10);
2761 if (*portend != '\0')
2763 *log_msgptr = US"bad destination port in \"udpsend\" modifier";
2767 /* Make a single-item host list. */
2768 h = store_get(sizeof(host_item));
2769 memset(h, 0, sizeof(host_item));
2774 if (string_is_ip_address(hostname, NULL))
2775 h->address = hostname, r = HOST_FOUND;
2777 r = host_find_byname(h, NULL, 0, NULL, FALSE);
2778 if (r == HOST_FIND_FAILED || r == HOST_FIND_AGAIN)
2780 *log_msgptr = US"DNS lookup failed in \"udpsend\" modifier";
2785 debug_printf_indent("udpsend [%s]:%d %s\n", h->address, portnum, arg);
2787 /*XXX this could better use sendto */
2788 r = s = ip_connectedsocket(SOCK_DGRAM, h->address, portnum, portnum,
2789 1, NULL, &errstr, NULL);
2790 if (r < 0) goto defer;
2792 r = send(s, arg, len, 0);
2795 errstr = US strerror(errno);
2803 string_sprintf("\"udpsend\" truncated from %d to %d octets", len, r);
2808 debug_printf_indent("udpsend %d bytes\n", r);
2813 *log_msgptr = string_sprintf("\"udpsend\" failed: %s", errstr);
2819 /*************************************************
2820 * Handle conditions/modifiers on an ACL item *
2821 *************************************************/
2823 /* Called from acl_check() below.
2827 cb ACL condition block - if NULL, result is OK
2828 where where called from
2829 addr the address being checked for RCPT, or NULL
2830 level the nesting level
2831 epp pointer to pass back TRUE if "endpass" encountered
2832 (applies only to "accept" and "discard")
2833 user_msgptr user message pointer
2834 log_msgptr log message pointer
2835 basic_errno pointer to where to put verify error
2837 Returns: OK - all conditions are met
2838 DISCARD - an "acl" condition returned DISCARD - only allowed
2839 for "accept" or "discard" verbs
2840 FAIL - at least one condition fails
2841 FAIL_DROP - an "acl" condition returned FAIL_DROP
2842 DEFER - can't tell at the moment (typically, lookup defer,
2843 but can be temporary callout problem)
2844 ERROR - ERROR from nested ACL or expansion failure or other
2849 acl_check_condition(int verb, acl_condition_block *cb, int where,
2850 address_item *addr, int level, BOOL *epp, uschar **user_msgptr,
2851 uschar **log_msgptr, int *basic_errno)
2853 uschar *user_message = NULL;
2854 uschar *log_message = NULL;
2856 #ifdef WITH_CONTENT_SCAN
2860 for (; cb != NULL; cb = cb->next)
2865 /* The message and log_message items set up messages to be used in
2866 case of rejection. They are expanded later. */
2868 if (cb->type == ACLC_MESSAGE)
2870 HDEBUG(D_acl) debug_printf_indent(" message: %s\n", cb->arg);
2871 user_message = cb->arg;
2875 if (cb->type == ACLC_LOG_MESSAGE)
2877 HDEBUG(D_acl) debug_printf_indent("l_message: %s\n", cb->arg);
2878 log_message = cb->arg;
2882 /* The endpass "condition" just sets a flag to show it occurred. This is
2883 checked at compile time to be on an "accept" or "discard" item. */
2885 if (cb->type == ACLC_ENDPASS)
2891 /* For other conditions and modifiers, the argument is expanded now for some
2892 of them, but not for all, because expansion happens down in some lower level
2893 checking functions in some cases. */
2895 if (!conditions[cb->type].expand_at_top)
2897 else if (!(arg = expand_string(cb->arg)))
2899 if (expand_string_forcedfail) continue;
2900 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s",
2901 cb->arg, expand_string_message);
2902 return search_find_defer ? DEFER : ERROR;
2905 /* Show condition, and expanded condition if it's different */
2910 debug_printf_indent("check %s%s %n",
2911 (!conditions[cb->type].is_modifier && cb->u.negated)? "!":"",
2912 conditions[cb->type].name, &lhswidth);
2914 if (cb->type == ACLC_SET)
2916 #ifndef DISABLE_DKIM
2917 if ( Ustrcmp(cb->u.varname, "dkim_verify_status") == 0
2918 || Ustrcmp(cb->u.varname, "dkim_verify_reason") == 0)
2920 debug_printf("%s ", cb->u.varname);
2926 debug_printf("acl_%s ", cb->u.varname);
2927 lhswidth += 5 + Ustrlen(cb->u.varname);
2931 debug_printf("= %s\n", cb->arg);
2934 debug_printf("%.*s= %s\n", lhswidth,
2938 /* Check that this condition makes sense at this time */
2940 if ((conditions[cb->type].forbids & (1 << where)) != 0)
2942 *log_msgptr = string_sprintf("cannot %s %s condition in %s ACL",
2943 conditions[cb->type].is_modifier ? "use" : "test",
2944 conditions[cb->type].name, acl_wherenames[where]);
2948 /* Run the appropriate test for each condition, or take the appropriate
2949 action for the remaining modifiers. */
2953 case ACLC_ADD_HEADER:
2957 /* A nested ACL that returns "discard" makes sense only for an "accept" or
2961 rc = acl_check_wargs(where, addr, arg, user_msgptr, log_msgptr);
2962 if (rc == DISCARD && verb != ACL_ACCEPT && verb != ACL_DISCARD)
2964 *log_msgptr = string_sprintf("nested ACL returned \"discard\" for "
2965 "\"%s\" command (only allowed with \"accept\" or \"discard\")",
2971 case ACLC_AUTHENTICATED:
2972 rc = (sender_host_authenticated == NULL)? FAIL :
2973 match_isinlist(sender_host_authenticated, &arg, 0, NULL, NULL, MCL_STRING,
2977 #ifdef EXPERIMENTAL_BRIGHTMAIL
2978 case ACLC_BMI_OPTIN:
2980 int old_pool = store_pool;
2981 store_pool = POOL_PERM;
2982 bmi_current_optin = string_copy(arg);
2983 store_pool = old_pool;
2988 case ACLC_CONDITION:
2989 /* The true/false parsing here should be kept in sync with that used in
2990 expand.c when dealing with ECOND_BOOL so that we don't have too many
2991 different definitions of what can be a boolean. */
2993 ? Ustrspn(arg+1, "0123456789") == Ustrlen(arg+1) /* Negative number */
2994 : Ustrspn(arg, "0123456789") == Ustrlen(arg)) /* Digits, or empty */
2995 rc = (Uatoi(arg) == 0)? FAIL : OK;
2997 rc = (strcmpic(arg, US"no") == 0 ||
2998 strcmpic(arg, US"false") == 0)? FAIL :
2999 (strcmpic(arg, US"yes") == 0 ||
3000 strcmpic(arg, US"true") == 0)? OK : DEFER;
3002 *log_msgptr = string_sprintf("invalid \"condition\" value \"%s\"", arg);
3005 case ACLC_CONTINUE: /* Always succeeds */
3010 const uschar *p = NULL;
3011 control_type = decode_control(arg, &p, where, log_msgptr);
3013 /* Check if this control makes sense at this time */
3015 if (controls_list[control_type].forbids & (1 << where))
3017 *log_msgptr = string_sprintf("cannot use \"control=%s\" in %s ACL",
3018 controls_list[control_type].name, acl_wherenames[where]);
3022 switch(control_type)
3024 case CONTROL_AUTH_UNADVERTISED:
3025 allow_auth_unadvertised = TRUE;
3028 #ifdef EXPERIMENTAL_BRIGHTMAIL
3029 case CONTROL_BMI_RUN:
3034 #ifndef DISABLE_DKIM
3035 case CONTROL_DKIM_VERIFY:
3036 dkim_disable_verify = TRUE;
3037 #ifdef EXPERIMENTAL_DMARC
3038 /* Since DKIM was blocked, skip DMARC too */
3039 dmarc_disable_verify = TRUE;
3040 dmarc_enable_forensic = FALSE;
3045 #ifdef EXPERIMENTAL_DMARC
3046 case CONTROL_DMARC_VERIFY:
3047 dmarc_disable_verify = TRUE;
3050 case CONTROL_DMARC_FORENSIC:
3051 dmarc_enable_forensic = TRUE;
3058 int fd, af, level, optname, value;
3059 /* If we are acting on stdin, the setsockopt may fail if stdin is not
3060 a socket; we can accept that, we'll just debug-log failures anyway. */
3061 fd = fileno(smtp_in);
3062 af = ip_get_address_family(fd);
3066 debug_printf_indent("smtp input is probably not a socket [%s], not setting DSCP\n",
3070 if (dscp_lookup(p+1, af, &level, &optname, &value))
3072 if (setsockopt(fd, level, optname, &value, sizeof(value)) < 0)
3074 HDEBUG(D_acl) debug_printf_indent("failed to set input DSCP[%s]: %s\n",
3075 p+1, strerror(errno));
3079 HDEBUG(D_acl) debug_printf_indent("set input DSCP to \"%s\"\n", p+1);
3084 *log_msgptr = string_sprintf("unrecognised DSCP value in \"control=%s\"", arg);
3090 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3098 case CONTROL_CASEFUL_LOCAL_PART:
3099 deliver_localpart = addr->cc_local_part;
3102 case CONTROL_CASELOWER_LOCAL_PART:
3103 deliver_localpart = addr->lc_local_part;
3106 case CONTROL_ENFORCE_SYNC:
3107 smtp_enforce_sync = TRUE;
3110 case CONTROL_NO_ENFORCE_SYNC:
3111 smtp_enforce_sync = FALSE;
3114 #ifdef WITH_CONTENT_SCAN
3115 case CONTROL_NO_MBOX_UNSPOOL:
3116 no_mbox_unspool = TRUE;
3120 case CONTROL_NO_MULTILINE:
3121 no_multiline_responses = TRUE;
3124 case CONTROL_NO_PIPELINING:
3125 pipelining_enable = FALSE;
3128 case CONTROL_NO_DELAY_FLUSH:
3129 disable_delay_flush = TRUE;
3132 case CONTROL_NO_CALLOUT_FLUSH:
3133 disable_callout_flush = TRUE;
3136 case CONTROL_FAKEREJECT:
3137 cancel_cutthrough_connection(TRUE, US"fakereject");
3138 case CONTROL_FAKEDEFER:
3139 fake_response = (control_type == CONTROL_FAKEDEFER) ? DEFER : FAIL;
3142 const uschar *pp = p + 1;
3143 while (*pp != 0) pp++;
3144 fake_response_text = expand_string(string_copyn(p+1, pp-p-1));
3149 /* Explicitly reset to default string */
3150 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).";
3154 case CONTROL_FREEZE:
3155 deliver_freeze = TRUE;
3156 deliver_frozen_at = time(NULL);
3157 freeze_tell = freeze_tell_config; /* Reset to configured value */
3158 if (Ustrncmp(p, "/no_tell", 8) == 0)
3165 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3168 cancel_cutthrough_connection(TRUE, US"item frozen");
3171 case CONTROL_QUEUE_ONLY:
3172 queue_only_policy = TRUE;
3173 cancel_cutthrough_connection(TRUE, US"queueing forced");
3176 case CONTROL_SUBMISSION:
3177 originator_name = US"";
3178 submission_mode = TRUE;
3181 if (Ustrncmp(p, "/sender_retain", 14) == 0)
3184 active_local_sender_retain = TRUE;
3185 active_local_from_check = FALSE;
3187 else if (Ustrncmp(p, "/domain=", 8) == 0)
3189 const uschar *pp = p + 8;
3190 while (*pp != 0 && *pp != '/') pp++;
3191 submission_domain = string_copyn(p+8, pp-p-8);
3194 /* The name= option must be last, because it swallows the rest of
3196 else if (Ustrncmp(p, "/name=", 6) == 0)
3198 const uschar *pp = p + 6;
3199 while (*pp != 0) pp++;
3200 submission_name = string_copy(parse_fix_phrase(p+6, pp-p-6,
3201 big_buffer, big_buffer_size));
3208 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3215 uschar * debug_tag = NULL;
3216 uschar * debug_opts = NULL;
3221 const uschar * pp = p+1;
3222 if (Ustrncmp(pp, "tag=", 4) == 0)
3224 for (pp += 4; *pp && *pp != '/';) pp++;
3225 debug_tag = string_copyn(p+5, pp-p-5);
3227 else if (Ustrncmp(pp, "opts=", 5) == 0)
3229 for (pp += 5; *pp && *pp != '/';) pp++;
3230 debug_opts = string_copyn(p+6, pp-p-6);
3232 else if (Ustrncmp(pp, "kill", 4) == 0)
3234 for (pp += 4; *pp && *pp != '/';) pp++;
3238 while (*pp && *pp != '/') pp++;
3243 debug_logging_stop();
3245 debug_logging_activate(debug_tag, debug_opts);
3249 case CONTROL_SUPPRESS_LOCAL_FIXUPS:
3250 suppress_local_fixups = TRUE;
3253 case CONTROL_CUTTHROUGH_DELIVERY:
3254 #ifndef DISABLE_PRDR
3259 /* Too hard to think about for now. We might in future cutthrough
3260 the case where both sides handle prdr and this-node prdr acl
3262 *log_msgptr = string_sprintf("PRDR on %s reception\n", arg);
3266 *log_msgptr = US"frozen";
3267 else if (queue_only_policy)
3268 *log_msgptr = US"queue-only";
3269 else if (fake_response == FAIL)
3270 *log_msgptr = US"fakereject";
3273 if (rcpt_count == 1)
3275 cutthrough.delivery = TRUE;
3278 const uschar * pp = p+1;
3279 if (Ustrncmp(pp, "defer=", 6) == 0)
3282 if (Ustrncmp(pp, "pass", 4) == 0) cutthrough.defer_pass = TRUE;
3283 /* else if (Ustrncmp(pp, "spool") == 0) ; default */
3286 while (*pp && *pp != '/') pp++;
3292 *log_msgptr = string_sprintf("\"control=%s\" on %s item",
3298 case CONTROL_UTF8_DOWNCONVERT:
3303 message_utf8_downconvert = 1;
3304 addr->prop.utf8_downcvt = TRUE;
3305 addr->prop.utf8_downcvt_maybe = FALSE;
3311 message_utf8_downconvert = 0;
3312 addr->prop.utf8_downcvt = FALSE;
3313 addr->prop.utf8_downcvt_maybe = FALSE;
3317 if (p[1] == '-' && p[2] == '1')
3319 message_utf8_downconvert = -1;
3320 addr->prop.utf8_downcvt = FALSE;
3321 addr->prop.utf8_downcvt_maybe = TRUE;
3325 *log_msgptr = US"bad option value for control=utf8_downconvert";
3329 message_utf8_downconvert = 1;
3330 addr->prop.utf8_downcvt = TRUE;
3331 addr->prop.utf8_downcvt_maybe = FALSE;
3341 #ifdef EXPERIMENTAL_DCC
3344 /* Separate the regular expression and any optional parameters. */
3345 const uschar * list = arg;
3346 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
3347 /* Run the dcc backend. */
3348 rc = dcc_process(&ss);
3349 /* Modify return code based upon the existence of options. */
3350 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size)))
3351 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
3352 rc = FAIL; /* FAIL so that the message is passed to the next ACL */
3357 #ifdef WITH_CONTENT_SCAN
3359 rc = mime_decode(&arg);
3365 int delay = readconf_readtime(arg, 0, FALSE);
3368 *log_msgptr = string_sprintf("syntax error in argument for \"delay\" "
3369 "modifier: \"%s\" is not a time value", arg);
3374 HDEBUG(D_acl) debug_printf_indent("delay modifier requests %d-second delay\n",
3379 debug_printf_indent("delay skipped in -bh checking mode\n");
3382 /* NOTE 1: Remember that we may be
3383 dealing with stdin/stdout here, in addition to TCP/IP connections.
3384 Also, delays may be specified for non-SMTP input, where smtp_out and
3385 smtp_in will be NULL. Whatever is done must work in all cases.
3387 NOTE 2: The added feature of flushing the output before a delay must
3388 apply only to SMTP input. Hence the test for smtp_out being non-NULL.
3393 if (smtp_out != NULL && !disable_delay_flush)
3396 #if !defined(NO_POLL_H) && defined (POLLRDHUP)
3402 p.fd = fileno(smtp_out);
3403 p.events = POLLRDHUP;
3406 if (poll(&p, n, delay*1000) > 0)
3407 HDEBUG(D_acl) debug_printf_indent("delay cancelled by peer close\n");
3410 /* It appears to be impossible to detect that a TCP/IP connection has
3411 gone away without reading from it. This means that we cannot shorten
3412 the delay below if the client goes away, because we cannot discover
3413 that the client has closed its end of the connection. (The connection
3414 is actually in a half-closed state, waiting for the server to close its
3415 end.) It would be nice to be able to detect this state, so that the
3416 Exim process is not held up unnecessarily. However, it seems that we
3417 can't. The poll() function does not do the right thing, and in any case
3418 it is not always available.
3421 while (delay > 0) delay = sleep(delay);
3428 #ifndef DISABLE_DKIM
3429 case ACLC_DKIM_SIGNER:
3430 if (dkim_cur_signer)
3431 rc = match_isinlist(dkim_cur_signer,
3432 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
3437 case ACLC_DKIM_STATUS:
3438 rc = match_isinlist(dkim_verify_status,
3439 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
3443 #ifdef EXPERIMENTAL_DMARC
3444 case ACLC_DMARC_STATUS:
3445 if (!dmarc_has_been_checked)
3447 dmarc_has_been_checked = TRUE;
3448 /* used long way of dmarc_exim_expand_query() in case we need more
3449 * view into the process in the future. */
3450 rc = match_isinlist(dmarc_exim_expand_query(DMARC_VERIFY_STATUS),
3451 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
3456 rc = verify_check_dnsbl(where, &arg, log_msgptr);
3460 rc = match_isinlist(addr->domain, &arg, 0, &domainlist_anchor,
3461 addr->domain_cache, MCL_DOMAIN, TRUE, CUSS &deliver_domain_data);
3464 /* The value in tls_cipher is the full cipher name, for example,
3465 TLSv1:DES-CBC3-SHA:168, whereas the values to test for are just the
3466 cipher names such as DES-CBC3-SHA. But program defensively. We don't know
3467 what may in practice come out of the SSL library - which at the time of
3468 writing is poorly documented. */
3470 case ACLC_ENCRYPTED:
3471 if (tls_in.cipher == NULL) rc = FAIL; else
3473 uschar *endcipher = NULL;
3474 uschar *cipher = Ustrchr(tls_in.cipher, ':');
3475 if (cipher == NULL) cipher = tls_in.cipher; else
3477 endcipher = Ustrchr(++cipher, ':');
3478 if (endcipher != NULL) *endcipher = 0;
3480 rc = match_isinlist(cipher, &arg, 0, NULL, NULL, MCL_STRING, TRUE, NULL);
3481 if (endcipher != NULL) *endcipher = ':';
3485 /* Use verify_check_this_host() instead of verify_check_host() so that
3486 we can pass over &host_data to catch any looked up data. Once it has been
3487 set, it retains its value so that it's still there if another ACL verb
3488 comes through here and uses the cache. However, we must put it into
3489 permanent store in case it is also expected to be used in a subsequent
3490 message in the same SMTP connection. */
3493 rc = verify_check_this_host(&arg, sender_host_cache, NULL,
3494 (sender_host_address == NULL)? US"" : sender_host_address,
3496 if (rc == DEFER) *log_msgptr = search_error_message;
3497 if (host_data) host_data = string_copy_malloc(host_data);
3500 case ACLC_LOCAL_PARTS:
3501 rc = match_isinlist(addr->cc_local_part, &arg, 0,
3502 &localpartlist_anchor, addr->localpart_cache, MCL_LOCALPART, TRUE,
3503 CUSS &deliver_localpart_data);
3506 case ACLC_LOG_REJECT_TARGET:
3510 const uschar *s = arg;
3512 while ((ss = string_nextinlist(&s, &sep, big_buffer, big_buffer_size)))
3514 if (Ustrcmp(ss, "main") == 0) logbits |= LOG_MAIN;
3515 else if (Ustrcmp(ss, "panic") == 0) logbits |= LOG_PANIC;
3516 else if (Ustrcmp(ss, "reject") == 0) logbits |= LOG_REJECT;
3519 logbits |= LOG_MAIN|LOG_REJECT;
3520 log_write(0, LOG_MAIN|LOG_PANIC, "unknown log name \"%s\" in "
3521 "\"log_reject_target\" in %s ACL", ss, acl_wherenames[where]);
3524 log_reject_target = logbits;
3531 const uschar *s = arg;
3537 if (Ustrncmp(s, "main", 4) == 0)
3538 { logbits |= LOG_MAIN; s += 4; }
3539 else if (Ustrncmp(s, "panic", 5) == 0)
3540 { logbits |= LOG_PANIC; s += 5; }
3541 else if (Ustrncmp(s, "reject", 6) == 0)
3542 { logbits |= LOG_REJECT; s += 6; }
3545 logbits = LOG_MAIN|LOG_PANIC;
3546 s = string_sprintf(":unknown log name in \"%s\" in "
3547 "\"logwrite\" in %s ACL", arg, acl_wherenames[where]);
3553 while (isspace(*s)) s++;
3556 if (logbits == 0) logbits = LOG_MAIN;
3557 log_write(0, logbits, "%s", string_printing(s));
3561 #ifdef WITH_CONTENT_SCAN
3562 case ACLC_MALWARE: /* Run the malware backend. */
3564 /* Separate the regular expression and any optional parameters. */
3565 const uschar * list = arg;
3566 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
3568 BOOL defer_ok = FALSE;
3571 while ((opt = string_nextinlist(&list, &sep, NULL, 0)))
3572 if (strcmpic(opt, US"defer_ok") == 0)
3574 else if ( strncmpic(opt, US"tmo=", 4) == 0
3575 && (timeout = readconf_readtime(opt+4, '\0', FALSE)) < 0
3578 *log_msgptr = string_sprintf("bad timeout value in '%s'", opt);
3582 rc = malware(ss, timeout);
3583 if (rc == DEFER && defer_ok)
3584 rc = FAIL; /* FAIL so that the message is passed to the next ACL */
3588 case ACLC_MIME_REGEX:
3589 rc = mime_regex(&arg);
3594 if (Ustrchr(arg, '/'))
3596 *log_msgptr = string_sprintf(
3597 "Directory separator not permitted in queue name: '%s'", arg);
3600 queue_name = string_copy_malloc(arg);
3603 case ACLC_RATELIMIT:
3604 rc = acl_ratelimit(arg, where, log_msgptr);
3607 case ACLC_RECIPIENTS:
3608 rc = match_address_list(CUS addr->address, TRUE, TRUE, &arg, NULL, -1, 0,
3609 CUSS &recipient_data);
3612 #ifdef WITH_CONTENT_SCAN
3618 case ACLC_REMOVE_HEADER:
3619 setup_remove_header(arg);
3622 case ACLC_SENDER_DOMAINS:
3625 sdomain = Ustrrchr(sender_address, '@');
3626 sdomain = sdomain ? sdomain + 1 : US"";
3627 rc = match_isinlist(sdomain, &arg, 0, &domainlist_anchor,
3628 sender_domain_cache, MCL_DOMAIN, TRUE, NULL);
3633 rc = match_address_list(CUS sender_address, TRUE, TRUE, &arg,
3634 sender_address_cache, -1, 0, CUSS &sender_data);
3637 /* Connection variables must persist forever */
3641 int old_pool = store_pool;
3642 if ( cb->u.varname[0] == 'c'
3643 #ifndef DISABLE_DKIM
3644 || cb->u.varname[0] == 'd'
3646 #ifndef DISABLE_EVENT
3647 || event_name /* An event is being delivered */
3650 store_pool = POOL_PERM;
3651 #ifndef DISABLE_DKIM /* Overwriteable dkim result variables */
3652 if (Ustrcmp(cb->u.varname, "dkim_verify_status") == 0)
3653 dkim_verify_status = string_copy(arg);
3654 else if (Ustrcmp(cb->u.varname, "dkim_verify_reason") == 0)
3655 dkim_verify_reason = string_copy(arg);
3658 acl_var_create(cb->u.varname)->data.ptr = string_copy(arg);
3659 store_pool = old_pool;
3663 #ifdef WITH_CONTENT_SCAN
3666 /* Separate the regular expression and any optional parameters. */
3667 const uschar * list = arg;
3668 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
3670 rc = spam(CUSS &ss);
3671 /* Modify return code based upon the existence of options. */
3672 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size)))
3673 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
3674 rc = FAIL; /* FAIL so that the message is passed to the next ACL */
3681 rc = spf_process(&arg, sender_address, SPF_PROCESS_NORMAL);
3683 case ACLC_SPF_GUESS:
3684 rc = spf_process(&arg, sender_address, SPF_PROCESS_GUESS);
3689 rc = acl_udpsend(arg, log_msgptr);
3692 /* If the verb is WARN, discard any user message from verification, because
3693 such messages are SMTP responses, not header additions. The latter come
3694 only from explicit "message" modifiers. However, put the user message into
3695 $acl_verify_message so it can be used in subsequent conditions or modifiers
3696 (until something changes it). */
3699 rc = acl_verify(where, addr, arg, user_msgptr, log_msgptr, basic_errno);
3701 acl_verify_message = *user_msgptr;
3702 if (verb == ACL_WARN) *user_msgptr = NULL;
3706 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown "
3707 "condition %d", cb->type);
3711 /* If a condition was negated, invert OK/FAIL. */
3713 if (!conditions[cb->type].is_modifier && cb->u.negated)
3714 if (rc == OK) rc = FAIL;
3715 else if (rc == FAIL || rc == FAIL_DROP) rc = OK;
3717 if (rc != OK) break; /* Conditions loop */
3721 /* If the result is the one for which "message" and/or "log_message" are used,
3722 handle the values of these modifiers. If there isn't a log message set, we make
3723 it the same as the user message.
3725 "message" is a user message that will be included in an SMTP response. Unless
3726 it is empty, it overrides any previously set user message.
3728 "log_message" is a non-user message, and it adds to any existing non-user
3729 message that is already set.
3731 Most verbs have but a single return for which the messages are relevant, but
3732 for "discard", it's useful to have the log message both when it succeeds and
3733 when it fails. For "accept", the message is used in the OK case if there is no
3734 "endpass", but (for backwards compatibility) in the FAIL case if "endpass" is
3737 if (*epp && rc == OK) user_message = NULL;
3739 if ((BIT(rc) & msgcond[verb]) != 0)
3742 uschar *old_user_msgptr = *user_msgptr;
3743 uschar *old_log_msgptr = (*log_msgptr != NULL)? *log_msgptr : old_user_msgptr;
3745 /* If the verb is "warn", messages generated by conditions (verification or
3746 nested ACLs) are always discarded. This also happens for acceptance verbs
3747 when they actually do accept. Only messages specified at this level are used.
3748 However, the value of an existing message is available in $acl_verify_message
3749 during expansions. */
3751 if (verb == ACL_WARN ||
3752 (rc == OK && (verb == ACL_ACCEPT || verb == ACL_DISCARD)))
3753 *log_msgptr = *user_msgptr = NULL;
3757 acl_verify_message = old_user_msgptr;
3758 expmessage = expand_string(user_message);
3761 if (!expand_string_forcedfail)
3762 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
3763 user_message, expand_string_message);
3765 else if (expmessage[0] != 0) *user_msgptr = expmessage;
3770 acl_verify_message = old_log_msgptr;
3771 expmessage = expand_string(log_message);
3774 if (!expand_string_forcedfail)
3775 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
3776 log_message, expand_string_message);
3778 else if (expmessage[0] != 0)
3780 *log_msgptr = (*log_msgptr == NULL)? expmessage :
3781 string_sprintf("%s: %s", expmessage, *log_msgptr);
3785 /* If no log message, default it to the user message */
3787 if (!*log_msgptr) *log_msgptr = *user_msgptr;
3790 acl_verify_message = NULL;
3798 /*************************************************
3799 * Get line from a literal ACL *
3800 *************************************************/
3802 /* This function is passed to acl_read() in order to extract individual lines
3803 of a literal ACL, which we access via static pointers. We can destroy the
3804 contents because this is called only once (the compiled ACL is remembered).
3806 This code is intended to treat the data in the same way as lines in the main
3807 Exim configuration file. That is:
3809 . Leading spaces are ignored.
3811 . A \ at the end of a line is a continuation - trailing spaces after the \
3812 are permitted (this is because I don't believe in making invisible things
3813 significant). Leading spaces on the continued part of a line are ignored.
3815 . Physical lines starting (significantly) with # are totally ignored, and
3816 may appear within a sequence of backslash-continued lines.
3818 . Blank lines are ignored, but will end a sequence of continuations.
3821 Returns: a pointer to the next line
3825 static uschar *acl_text; /* Current pointer in the text */
3826 static uschar *acl_text_end; /* Points one past the terminating '0' */
3834 /* This loop handles leading blank lines and comments. */
3838 while (isspace(*acl_text)) acl_text++; /* Leading spaces/empty lines */
3839 if (*acl_text == 0) return NULL; /* No more data */
3840 yield = acl_text; /* Potential data line */
3842 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3844 /* If we hit the end before a newline, we have the whole logical line. If
3845 it's a comment, there's no more data to be given. Otherwise, yield it. */
3847 if (*acl_text == 0) return (*yield == '#')? NULL : yield;
3849 /* After reaching a newline, end this loop if the physical line does not
3850 start with '#'. If it does, it's a comment, and the loop continues. */
3852 if (*yield != '#') break;
3855 /* This loop handles continuations. We know we have some real data, ending in
3856 newline. See if there is a continuation marker at the end (ignoring trailing
3857 white space). We know that *yield is not white space, so no need to test for
3858 cont > yield in the backwards scanning loop. */
3863 for (cont = acl_text - 1; isspace(*cont); cont--);
3865 /* If no continuation follows, we are done. Mark the end of the line and
3874 /* We have encountered a continuation. Skip over whitespace at the start of
3875 the next line, and indeed the whole of the next line or lines if they are
3880 while (*(++acl_text) == ' ' || *acl_text == '\t');
3881 if (*acl_text != '#') break;
3882 while (*(++acl_text) != 0 && *acl_text != '\n');
3885 /* We have the start of a continuation line. Move all the rest of the data
3886 to join onto the previous line, and then find its end. If the end is not a
3887 newline, we are done. Otherwise loop to look for another continuation. */
3889 memmove(cont, acl_text, acl_text_end - acl_text);
3890 acl_text_end -= acl_text - cont;
3892 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3893 if (*acl_text == 0) return yield;
3896 /* Control does not reach here */
3903 /*************************************************
3904 * Check access using an ACL *
3905 *************************************************/
3907 /* This function is called from address_check. It may recurse via
3908 acl_check_condition() - hence the use of a level to stop looping. The ACL is
3909 passed as a string which is expanded. A forced failure implies no access check
3910 is required. If the result is a single word, it is taken as the name of an ACL
3911 which is sought in the global ACL tree. Otherwise, it is taken as literal ACL
3912 text, complete with newlines, and parsed as such. In both cases, the ACL check
3913 is then run. This function uses an auxiliary function for acl_read() to call
3914 for reading individual lines of a literal ACL. This is acl_getline(), which
3915 appears immediately above.
3918 where where called from
3919 addr address item when called from RCPT; otherwise NULL
3920 s the input string; NULL is the same as an empty ACL => DENY
3921 user_msgptr where to put a user error (for SMTP response)
3922 log_msgptr where to put a logging message (not for SMTP response)
3924 Returns: OK access is granted
3925 DISCARD access is apparently granted...
3926 FAIL access is denied
3927 FAIL_DROP access is denied; drop the connection
3928 DEFER can't tell at the moment
3933 acl_check_internal(int where, address_item *addr, uschar *s,
3934 uschar **user_msgptr, uschar **log_msgptr)
3937 acl_block *acl = NULL;
3938 uschar *acl_name = US"inline ACL";
3941 /* Catch configuration loops */
3945 *log_msgptr = US"ACL nested too deep: possible loop";
3951 HDEBUG(D_acl) debug_printf_indent("ACL is NULL: implicit DENY\n");
3955 /* At top level, we expand the incoming string. At lower levels, it has already
3956 been expanded as part of condition processing. */
3960 if (!(ss = expand_string(s)))
3962 if (expand_string_forcedfail) return OK;
3963 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s", s,
3964 expand_string_message);
3970 while (isspace(*ss)) ss++;
3972 /* If we can't find a named ACL, the default is to parse it as an inline one.
3973 (Unless it begins with a slash; non-existent files give rise to an error.) */
3977 /* Handle the case of a string that does not contain any spaces. Look for a
3978 named ACL among those read from the configuration, or a previously read file.
3979 It is possible that the pointer to the ACL is NULL if the configuration
3980 contains a name with no data. If not found, and the text begins with '/',
3981 read an ACL from a file, and save it so it can be re-used. */
3983 if (Ustrchr(ss, ' ') == NULL)
3985 tree_node *t = tree_search(acl_anchor, ss);
3988 acl = (acl_block *)(t->data.ptr);
3991 HDEBUG(D_acl) debug_printf_indent("ACL \"%s\" is empty: implicit DENY\n", ss);
3994 acl_name = string_sprintf("ACL \"%s\"", ss);
3995 HDEBUG(D_acl) debug_printf_indent("using ACL \"%s\"\n", ss);
3998 else if (*ss == '/')
4000 struct stat statbuf;
4001 fd = Uopen(ss, O_RDONLY, 0);
4004 *log_msgptr = string_sprintf("failed to open ACL file \"%s\": %s", ss,
4009 if (fstat(fd, &statbuf) != 0)
4011 *log_msgptr = string_sprintf("failed to fstat ACL file \"%s\": %s", ss,
4016 acl_text = store_get(statbuf.st_size + 1);
4017 acl_text_end = acl_text + statbuf.st_size + 1;
4019 if (read(fd, acl_text, statbuf.st_size) != statbuf.st_size)
4021 *log_msgptr = string_sprintf("failed to read ACL file \"%s\": %s",
4022 ss, strerror(errno));
4025 acl_text[statbuf.st_size] = 0;
4028 acl_name = string_sprintf("ACL \"%s\"", ss);
4029 HDEBUG(D_acl) debug_printf_indent("read ACL from file %s\n", ss);
4033 /* Parse an ACL that is still in text form. If it came from a file, remember it
4034 in the ACL tree, having read it into the POOL_PERM store pool so that it
4035 persists between multiple messages. */
4039 int old_pool = store_pool;
4040 if (fd >= 0) store_pool = POOL_PERM;
4041 acl = acl_read(acl_getline, log_msgptr);
4042 store_pool = old_pool;
4043 if (acl == NULL && *log_msgptr != NULL) return ERROR;
4046 tree_node *t = store_get_perm(sizeof(tree_node) + Ustrlen(ss));
4047 Ustrcpy(t->name, ss);
4049 (void)tree_insertnode(&acl_anchor, t);
4053 /* Now we have an ACL to use. It's possible it may be NULL. */
4058 int basic_errno = 0;
4059 BOOL endpass_seen = FALSE;
4060 BOOL acl_quit_check = acl_level == 0
4061 && (where == ACL_WHERE_QUIT || where == ACL_WHERE_NOTQUIT);
4063 *log_msgptr = *user_msgptr = NULL;
4064 acl_temp_details = FALSE;
4066 HDEBUG(D_acl) debug_printf_indent("processing \"%s\"\n", verbs[acl->verb]);
4068 /* Clear out any search error message from a previous check before testing
4071 search_error_message = NULL;
4072 cond = acl_check_condition(acl->verb, acl->condition, where, addr, acl_level,
4073 &endpass_seen, user_msgptr, log_msgptr, &basic_errno);
4075 /* Handle special returns: DEFER causes a return except on a WARN verb;
4076 ERROR always causes a return. */
4081 HDEBUG(D_acl) debug_printf_indent("%s: condition test deferred in %s\n", verbs[acl->verb], acl_name);
4082 if (basic_errno != ERRNO_CALLOUTDEFER)
4084 if (search_error_message != NULL && *search_error_message != 0)
4085 *log_msgptr = search_error_message;
4086 if (smtp_return_error_details) acl_temp_details = TRUE;
4090 acl_temp_details = TRUE;
4092 if (acl->verb != ACL_WARN) return DEFER;
4095 default: /* Paranoia */
4097 HDEBUG(D_acl) debug_printf_indent("%s: condition test error in %s\n", verbs[acl->verb], acl_name);
4101 HDEBUG(D_acl) debug_printf_indent("%s: condition test succeeded in %s\n",
4102 verbs[acl->verb], acl_name);
4106 HDEBUG(D_acl) debug_printf_indent("%s: condition test failed in %s\n", verbs[acl->verb], acl_name);
4109 /* DISCARD and DROP can happen only from a nested ACL condition, and
4110 DISCARD can happen only for an "accept" or "discard" verb. */
4113 HDEBUG(D_acl) debug_printf_indent("%s: condition test yielded \"discard\" in %s\n",
4114 verbs[acl->verb], acl_name);
4118 HDEBUG(D_acl) debug_printf_indent("%s: condition test yielded \"drop\" in %s\n",
4119 verbs[acl->verb], acl_name);
4123 /* At this point, cond for most verbs is either OK or FAIL or (as a result of
4124 a nested ACL condition) FAIL_DROP. However, for WARN, cond may be DEFER, and
4125 for ACCEPT and DISCARD, it may be DISCARD after a nested ACL call. */
4130 if (cond == OK || cond == DISCARD)
4132 HDEBUG(D_acl) debug_printf_indent("end of %s: ACCEPT\n", acl_name);
4137 HDEBUG(D_acl) debug_printf_indent("accept: endpass encountered - denying access\n");
4145 HDEBUG(D_acl) debug_printf_indent("end of %s: DEFER\n", acl_name);
4146 if (acl_quit_check) goto badquit;
4147 acl_temp_details = TRUE;
4155 HDEBUG(D_acl) debug_printf_indent("end of %s: DENY\n", acl_name);
4156 if (acl_quit_check) goto badquit;
4162 if (cond == OK || cond == DISCARD)
4164 HDEBUG(D_acl) debug_printf_indent("end of %s: DISCARD\n", acl_name);
4165 if (acl_quit_check) goto badquit;
4170 HDEBUG(D_acl) debug_printf_indent("discard: endpass encountered - denying access\n");
4178 HDEBUG(D_acl) debug_printf_indent("end of %s: DROP\n", acl_name);
4179 if (acl_quit_check) goto badquit;
4187 HDEBUG(D_acl) debug_printf_indent("end of %s: not OK\n", acl_name);
4188 if (acl_quit_check) goto badquit;
4195 acl_warn(where, *user_msgptr, *log_msgptr);
4196 else if (cond == DEFER && LOGGING(acl_warn_skipped))
4197 log_write(0, LOG_MAIN, "%s Warning: ACL \"warn\" statement skipped: "
4198 "condition test deferred%s%s", host_and_ident(TRUE),
4199 (*log_msgptr == NULL)? US"" : US": ",
4200 (*log_msgptr == NULL)? US"" : *log_msgptr);
4201 *log_msgptr = *user_msgptr = NULL; /* In case implicit DENY follows */
4205 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown verb %d",
4210 /* Pass to the next ACL item */
4215 /* We have reached the end of the ACL. This is an implicit DENY. */
4217 HDEBUG(D_acl) debug_printf_indent("end of %s: implicit DENY\n", acl_name);
4221 *log_msgptr = string_sprintf("QUIT or not-QUIT toplevel ACL may not fail "
4222 "('%s' verb used incorrectly)", verbs[acl->verb]);
4229 /* Same args as acl_check_internal() above, but the string s is
4230 the name of an ACL followed optionally by up to 9 space-separated arguments.
4231 The name and args are separately expanded. Args go into $acl_arg globals. */
4233 acl_check_wargs(int where, address_item *addr, const uschar *s,
4234 uschar **user_msgptr, uschar **log_msgptr)
4237 uschar * tmp_arg[9]; /* must match acl_arg[] */
4238 uschar * sav_arg[9]; /* must match acl_arg[] */
4244 if (!(tmp = string_dequote(&s)) || !(name = expand_string(tmp)))
4247 for (i = 0; i < 9; i++)
4249 while (*s && isspace(*s)) s++;
4251 if (!(tmp = string_dequote(&s)) || !(tmp_arg[i] = expand_string(tmp)))
4258 sav_narg = acl_narg;
4260 for (i = 0; i < acl_narg; i++)
4262 sav_arg[i] = acl_arg[i];
4263 acl_arg[i] = tmp_arg[i];
4267 sav_arg[i] = acl_arg[i];
4268 acl_arg[i++] = NULL;
4272 ret = acl_check_internal(where, addr, name, user_msgptr, log_msgptr);
4275 acl_narg = sav_narg;
4276 for (i = 0; i < 9; i++) acl_arg[i] = sav_arg[i];
4280 if (expand_string_forcedfail) return ERROR;
4281 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s",
4282 tmp, expand_string_message);
4283 return search_find_defer?DEFER:ERROR;
4288 /*************************************************
4289 * Check access using an ACL *
4290 *************************************************/
4292 /* Alternate interface for ACL, used by expansions */
4294 acl_eval(int where, uschar *s, uschar **user_msgptr, uschar **log_msgptr)
4297 address_item *addr = NULL;
4300 *user_msgptr = *log_msgptr = NULL;
4301 sender_verified_failed = NULL;
4302 ratelimiters_cmd = NULL;
4303 log_reject_target = LOG_MAIN|LOG_REJECT;
4305 if (where == ACL_WHERE_RCPT)
4307 adb = address_defaults;
4309 addr->address = expand_string(US"$local_part@$domain");
4310 addr->domain = deliver_domain;
4311 addr->local_part = deliver_localpart;
4312 addr->cc_local_part = deliver_localpart;
4313 addr->lc_local_part = deliver_localpart;
4317 rc = acl_check_internal(where, addr, s, user_msgptr, log_msgptr);
4324 /* This is the external interface for ACL checks. It sets up an address and the
4325 expansions for $domain and $local_part when called after RCPT, then calls
4326 acl_check_internal() to do the actual work.
4329 where ACL_WHERE_xxxx indicating where called from
4330 recipient RCPT address for RCPT check, else NULL
4331 s the input string; NULL is the same as an empty ACL => DENY
4332 user_msgptr where to put a user error (for SMTP response)
4333 log_msgptr where to put a logging message (not for SMTP response)
4335 Returns: OK access is granted by an ACCEPT verb
4336 DISCARD access is granted by a DISCARD verb
4337 FAIL access is denied
4338 FAIL_DROP access is denied; drop the connection
4339 DEFER can't tell at the moment
4342 int acl_where = ACL_WHERE_UNKNOWN;
4345 acl_check(int where, uschar *recipient, uschar *s, uschar **user_msgptr,
4346 uschar **log_msgptr)
4350 address_item *addr = NULL;
4352 *user_msgptr = *log_msgptr = NULL;
4353 sender_verified_failed = NULL;
4354 ratelimiters_cmd = NULL;
4355 log_reject_target = LOG_MAIN|LOG_REJECT;
4357 #ifndef DISABLE_PRDR
4358 if (where==ACL_WHERE_RCPT || where==ACL_WHERE_VRFY || where==ACL_WHERE_PRDR)
4360 if (where==ACL_WHERE_RCPT || where==ACL_WHERE_VRFY)
4363 adb = address_defaults;
4365 addr->address = recipient;
4366 if (deliver_split_address(addr) == DEFER)
4368 *log_msgptr = US"defer in percent_hack_domains check";
4372 if ((addr->prop.utf8_msg = message_smtputf8))
4374 addr->prop.utf8_downcvt = message_utf8_downconvert == 1;
4375 addr->prop.utf8_downcvt_maybe = message_utf8_downconvert == -1;
4378 deliver_domain = addr->domain;
4379 deliver_localpart = addr->local_part;
4384 rc = acl_check_internal(where, addr, s, user_msgptr, log_msgptr);
4386 acl_where = ACL_WHERE_UNKNOWN;
4388 /* Cutthrough - if requested,
4389 and WHERE_RCPT and not yet opened conn as result of recipient-verify,
4390 and rcpt acl returned accept,
4391 and first recipient (cancel on any subsequents)
4392 open one now and run it up to RCPT acceptance.
4393 A failed verify should cancel cutthrough request,
4394 and will pass the fail to the originator.
4395 Initial implementation: dual-write to spool.
4396 Assume the rxd datastream is now being copied byte-for-byte to an open cutthrough connection.
4398 Cease cutthrough copy on rxd final dot; do not send one.
4400 On a data acl, if not accept and a cutthrough conn is open, hard-close it (no SMTP niceness).
4402 On data acl accept, terminate the dataphase on an open cutthrough conn. If accepted or
4403 perm-rejected, reflect that to the original sender - and dump the spooled copy.
4404 If temp-reject, close the conn (and keep the spooled copy).
4405 If conn-failure, no action (and keep the spooled copy).
4409 case ACL_WHERE_RCPT:
4410 #ifndef DISABLE_PRDR
4411 case ACL_WHERE_PRDR:
4414 if (host_checking_callout) /* -bhc mode */
4415 cancel_cutthrough_connection(TRUE, US"host-checking mode");
4418 && cutthrough.delivery
4419 && rcpt_count > cutthrough.nrcpt
4420 && (rc = open_cutthrough_connection(addr)) == DEFER
4422 if (cutthrough.defer_pass)
4424 uschar * s = addr->message;
4425 /* Horrid kludge to recover target's SMTP message */
4427 do --s; while (!isdigit(*s));
4428 if (*--s && isdigit(*s) && *--s && isdigit(*s)) *user_msgptr = s;
4429 acl_temp_details = TRUE;
4433 HDEBUG(D_acl) debug_printf_indent("cutthrough defer; will spool\n");
4438 case ACL_WHERE_PREDATA:
4440 cutthrough_predata();
4442 cancel_cutthrough_connection(TRUE, US"predata acl not ok");
4445 case ACL_WHERE_QUIT:
4446 case ACL_WHERE_NOTQUIT:
4447 /* Drop cutthrough conns, and drop heldopen verify conns if
4448 the previous was not DATA */
4450 uschar prev = smtp_connection_had[smtp_ch_index-2];
4451 BOOL dropverify = !(prev == SCH_DATA || prev == SCH_BDAT);
4453 cancel_cutthrough_connection(dropverify, US"quit or conndrop");
4461 deliver_domain = deliver_localpart = deliver_address_data =
4462 sender_address_data = NULL;
4464 /* A DISCARD response is permitted only for message ACLs, excluding the PREDATA
4465 ACL, which is really in the middle of an SMTP command. */
4469 if (where > ACL_WHERE_NOTSMTP || where == ACL_WHERE_PREDATA)
4471 log_write(0, LOG_MAIN|LOG_PANIC, "\"discard\" verb not allowed in %s "
4472 "ACL", acl_wherenames[where]);
4478 /* A DROP response is not permitted from MAILAUTH */
4480 if (rc == FAIL_DROP && where == ACL_WHERE_MAILAUTH)
4482 log_write(0, LOG_MAIN|LOG_PANIC, "\"drop\" verb not allowed in %s "
4483 "ACL", acl_wherenames[where]);
4487 /* Before giving a response, take a look at the length of any user message, and
4488 split it up into multiple lines if possible. */
4490 *user_msgptr = string_split_message(*user_msgptr);
4491 if (fake_response != OK)
4492 fake_response_text = string_split_message(fake_response_text);
4498 /*************************************************
4499 * Create ACL variable *
4500 *************************************************/
4502 /* Create an ACL variable or reuse an existing one. ACL variables are in a
4503 binary tree (see tree.c) with acl_var_c and acl_var_m as root nodes.
4506 name pointer to the variable's name, starting with c or m
4508 Returns the pointer to variable's tree node
4512 acl_var_create(uschar * name)
4514 tree_node * node, ** root = name[0] == 'c' ? &acl_var_c : &acl_var_m;
4515 if (!(node = tree_search(*root, name)))
4517 node = store_get(sizeof(tree_node) + Ustrlen(name));
4518 Ustrcpy(node->name, name);
4519 (void)tree_insertnode(root, node);
4521 node->data.ptr = NULL;
4527 /*************************************************
4528 * Write an ACL variable in spool format *
4529 *************************************************/
4531 /* This function is used as a callback for tree_walk when writing variables to
4532 the spool file. To retain spool file compatibility, what is written is -aclc or
4533 -aclm followed by the rest of the name and the data length, space separated,
4534 then the value itself, starting on a new line, and terminated by an additional
4535 newline. When we had only numbered ACL variables, the first line might look
4536 like this: "-aclc 5 20". Now it might be "-aclc foo 20" for the variable called
4540 name of the variable
4541 value of the variable
4542 ctx FILE pointer (as a void pointer)
4548 acl_var_write(uschar *name, uschar *value, void *ctx)
4550 FILE *f = (FILE *)ctx;
4551 fprintf(f, "-acl%c %s %d\n%s\n", name[0], name+1, Ustrlen(value), value);