1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2016 */
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[] = {
33 /* For each verb, the conditions for which "message" or "log_message" are used
34 are held as a bitmap. This is to avoid expanding the strings unnecessarily. For
35 "accept", the FAIL case is used only after "endpass", but that is selected in
38 static int msgcond[] = {
39 (1<<OK) | (1<<FAIL) | (1<<FAIL_DROP), /* accept */
42 (1<<OK) | (1<<FAIL) | (1<<FAIL_DROP), /* discard */
44 (1<<FAIL) | (1<<FAIL_DROP), /* require */
48 /* ACL condition and modifier codes - keep in step with the table that
55 #ifdef EXPERIMENTAL_BRIGHTMAIL
61 #ifdef EXPERIMENTAL_DCC
64 #ifdef WITH_CONTENT_SCAN
72 #ifdef EXPERIMENTAL_DMARC
82 ACLC_LOG_REJECT_TARGET,
84 #ifdef WITH_CONTENT_SCAN
88 #ifdef WITH_CONTENT_SCAN
94 #ifdef WITH_CONTENT_SCAN
101 #ifdef WITH_CONTENT_SCAN
104 #ifdef EXPERIMENTAL_SPF
111 /* ACL conditions/modifiers: "delay", "control", "continue", "endpass",
112 "message", "log_message", "log_reject_target", "logwrite", "queue" and "set" are
113 modifiers that look like conditions but always return TRUE. They are used for
114 their side effects. */
116 typedef struct condition_def {
119 /* Flag to indicate the condition/modifier has a string expansion done
120 at the outer level. In the other cases, expansion already occurs in the
121 checking functions. */
122 BOOL expand_at_top:1;
126 /* Bit map vector of which conditions and modifiers are not allowed at certain
127 times. For each condition and modifier, there's a bitmap of dis-allowed times.
128 For some, it is easier to specify the negation of a small number of allowed
134 static condition_def conditions[] = {
135 { US"acl", FALSE, FALSE, 0 },
137 { US"add_header", TRUE, TRUE,
139 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)|
140 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
144 (1<<ACL_WHERE_MIME)|(1<<ACL_WHERE_NOTSMTP)|
146 (1<<ACL_WHERE_NOTSMTP_START)),
149 { US"authenticated", FALSE, FALSE,
150 (1<<ACL_WHERE_NOTSMTP)|
151 (1<<ACL_WHERE_NOTSMTP_START)|
152 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO),
154 #ifdef EXPERIMENTAL_BRIGHTMAIL
155 { US"bmi_optin", TRUE, TRUE,
157 (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)|
158 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_MIME)|
159 # ifndef DISABLE_PRDR
162 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
163 (1<<ACL_WHERE_MAILAUTH)|
164 (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)|
165 (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_PREDATA)|
166 (1<<ACL_WHERE_NOTSMTP_START),
169 { US"condition", TRUE, FALSE, 0 },
170 { 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 { US"control", TRUE, TRUE, 0 },
176 #ifdef EXPERIMENTAL_DCC
177 { US"dcc", TRUE, FALSE,
179 ~((1<<ACL_WHERE_DATA)|
180 # ifndef DISABLE_PRDR
183 (1<<ACL_WHERE_NOTSMTP)),
186 #ifdef WITH_CONTENT_SCAN
187 { US"decode", TRUE, FALSE, (unsigned int) ~(1<<ACL_WHERE_MIME) },
190 { US"delay", TRUE, TRUE, (1<<ACL_WHERE_NOTQUIT) },
192 { US"dkim_signers", TRUE, FALSE, (unsigned int) ~(1<<ACL_WHERE_DKIM) },
193 { US"dkim_status", TRUE, FALSE, (unsigned int) ~(1<<ACL_WHERE_DKIM) },
195 #ifdef EXPERIMENTAL_DMARC
196 { US"dmarc_status", TRUE, FALSE, (unsigned int) ~(1<<ACL_WHERE_DATA) },
199 /* Explicit key lookups can be made in non-smtp ACLs so pass
200 always and check in the verify processing itself. */
201 { US"dnslists", TRUE, FALSE, 0 },
203 { US"domains", FALSE, FALSE,
205 ~((1<<ACL_WHERE_RCPT)
212 { US"encrypted", FALSE, FALSE,
213 (1<<ACL_WHERE_NOTSMTP)|
214 (1<<ACL_WHERE_CONNECT)|
215 (1<<ACL_WHERE_NOTSMTP_START)|
219 { US"endpass", TRUE, TRUE, 0 },
221 { US"hosts", FALSE, FALSE,
222 (1<<ACL_WHERE_NOTSMTP)|
223 (1<<ACL_WHERE_NOTSMTP_START),
225 { US"local_parts", FALSE, FALSE,
227 ~((1<<ACL_WHERE_RCPT)
235 { US"log_message", TRUE, TRUE, 0 },
236 { US"log_reject_target", TRUE, TRUE, 0 },
237 { US"logwrite", TRUE, TRUE, 0 },
239 #ifdef WITH_CONTENT_SCAN
240 { US"malware", TRUE, FALSE,
242 ~((1<<ACL_WHERE_DATA)|
243 # ifndef DISABLE_PRDR
246 (1<<ACL_WHERE_NOTSMTP)),
250 { US"message", TRUE, TRUE, 0 },
251 #ifdef WITH_CONTENT_SCAN
252 { US"mime_regex", TRUE, FALSE, (unsigned int) ~(1<<ACL_WHERE_MIME) },
255 { US"queue", TRUE, TRUE,
256 (1<<ACL_WHERE_NOTSMTP)|
263 { US"ratelimit", TRUE, FALSE, 0 },
264 { US"recipients", FALSE, FALSE, (unsigned int) ~(1<<ACL_WHERE_RCPT) },
266 #ifdef WITH_CONTENT_SCAN
267 { US"regex", TRUE, FALSE,
269 ~((1<<ACL_WHERE_DATA)|
270 # ifndef DISABLE_PRDR
273 (1<<ACL_WHERE_NOTSMTP)|
274 (1<<ACL_WHERE_MIME)),
278 { US"remove_header", TRUE, TRUE,
280 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)|
281 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
285 (1<<ACL_WHERE_MIME)|(1<<ACL_WHERE_NOTSMTP)|
286 (1<<ACL_WHERE_NOTSMTP_START)),
288 { US"sender_domains", FALSE, FALSE,
289 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)|
291 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
292 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
293 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
295 { US"senders", FALSE, FALSE,
296 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)|
298 (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)|
299 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
300 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY),
303 { US"set", TRUE, TRUE, 0 },
305 #ifdef WITH_CONTENT_SCAN
306 { US"spam", TRUE, FALSE,
308 ~((1<<ACL_WHERE_DATA)|
309 # ifndef DISABLE_PRDR
312 (1<<ACL_WHERE_NOTSMTP)),
315 #ifdef EXPERIMENTAL_SPF
316 { US"spf", TRUE, FALSE,
317 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)|
319 (1<<ACL_WHERE_MAILAUTH)|
320 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
321 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY)|
322 (1<<ACL_WHERE_NOTSMTP)|
323 (1<<ACL_WHERE_NOTSMTP_START),
325 { US"spf_guess", TRUE, FALSE,
326 (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)|
328 (1<<ACL_WHERE_MAILAUTH)|
329 (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)|
330 (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY)|
331 (1<<ACL_WHERE_NOTSMTP)|
332 (1<<ACL_WHERE_NOTSMTP_START),
335 { US"udpsend", TRUE, TRUE, 0 },
337 /* Certain types of verify are always allowed, so we let it through
338 always and check in the verify function itself */
339 { US"verify", TRUE, FALSE,
346 /* Return values from decode_control(); used as index so keep in step
347 with the controls_list table that follows! */
350 CONTROL_AUTH_UNADVERTISED,
351 #ifdef EXPERIMENTAL_BRIGHTMAIL
354 CONTROL_CASEFUL_LOCAL_PART,
355 CONTROL_CASELOWER_LOCAL_PART,
356 CONTROL_CUTTHROUGH_DELIVERY,
361 #ifdef EXPERIMENTAL_DMARC
362 CONTROL_DMARC_VERIFY,
363 CONTROL_DMARC_FORENSIC,
366 CONTROL_ENFORCE_SYNC,
367 CONTROL_ERROR, /* pseudo-value for decode errors */
372 CONTROL_NO_CALLOUT_FLUSH,
373 CONTROL_NO_DELAY_FLUSH,
374 CONTROL_NO_ENFORCE_SYNC,
375 #ifdef WITH_CONTENT_SCAN
376 CONTROL_NO_MBOX_UNSPOOL,
378 CONTROL_NO_MULTILINE,
379 CONTROL_NO_PIPELINING,
383 CONTROL_SUPPRESS_LOCAL_FIXUPS,
385 CONTROL_UTF8_DOWNCONVERT,
391 /* Structure listing various control arguments, with their characteristics.
392 For each control, there's a bitmap of dis-allowed times. For some, it is easier
393 to specify the negation of a small number of allowed times. */
395 typedef struct control_def {
397 BOOL has_option; /* Has /option(s) following */
398 unsigned forbids; /* bitmap of dis-allowed times */
401 static control_def controls_list[] = {
402 { US"allow_auth_unadvertised", FALSE,
404 ~((1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO))
406 #ifdef EXPERIMENTAL_BRIGHTMAIL
407 { US"bmi_run", FALSE, 0 },
409 { US"caseful_local_part", FALSE, (unsigned) ~(1<<ACL_WHERE_RCPT) },
410 { US"caselower_local_part", FALSE, (unsigned) ~(1<<ACL_WHERE_RCPT) },
411 { US"cutthrough_delivery", TRUE, 0 },
412 { US"debug", TRUE, 0 },
415 { US"dkim_disable_verify", FALSE,
416 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)|
417 # ifndef DISABLE_PRDR
420 (1<<ACL_WHERE_NOTSMTP_START)
424 #ifdef EXPERIMENTAL_DMARC
425 { US"dmarc_disable_verify", FALSE,
426 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_NOTSMTP_START)
428 { US"dmarc_enable_forensic", FALSE,
429 (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_NOTSMTP_START)
434 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_NOTSMTP_START)|(1<<ACL_WHERE_NOTQUIT)
436 { US"enforce_sync", FALSE,
437 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_NOTSMTP_START)
440 /* Pseudo-value for decode errors */
441 { US"error", FALSE, 0 },
443 { US"fakedefer", TRUE,
445 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)|
446 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
452 { US"fakereject", TRUE,
454 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)|
455 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
463 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)|
464 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
465 // (1<<ACL_WHERE_PRDR)| /* Not allow one user to freeze for all */
466 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME))
469 { US"no_callout_flush", FALSE,
470 (1<<ACL_WHERE_NOTSMTP)| (1<<ACL_WHERE_NOTSMTP_START)
472 { US"no_delay_flush", FALSE,
473 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_NOTSMTP_START)
476 { US"no_enforce_sync", FALSE,
477 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_NOTSMTP_START)
479 #ifdef WITH_CONTENT_SCAN
480 { US"no_mbox_unspool", FALSE,
482 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)|
483 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
484 // (1<<ACL_WHERE_PRDR)| /* Not allow one user to freeze for all */
488 { US"no_multiline_responses", FALSE,
489 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_NOTSMTP_START)
491 { US"no_pipelining", FALSE,
492 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_NOTSMTP_START)
495 { US"queue_only", FALSE,
497 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)|
498 (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|
499 // (1<<ACL_WHERE_PRDR)| /* Not allow one user to freeze for all */
500 (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME))
502 { US"submission", TRUE,
504 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA))
506 { US"suppress_local_fixups", FALSE,
508 ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)|
509 (1<<ACL_WHERE_NOTSMTP_START))
512 { US"utf8_downconvert", TRUE, 0 }
516 /* Support data structures for Client SMTP Authorization. acl_verify_csa()
517 caches its result in a tree to avoid repeated DNS queries. The result is an
518 integer code which is used as an index into the following tables of
519 explanatory strings and verification return codes. */
521 static tree_node *csa_cache = NULL;
523 enum { CSA_UNKNOWN, CSA_OK, CSA_DEFER_SRV, CSA_DEFER_ADDR,
524 CSA_FAIL_EXPLICIT, CSA_FAIL_DOMAIN, CSA_FAIL_NOADDR, CSA_FAIL_MISMATCH };
526 /* The acl_verify_csa() return code is translated into an acl_verify() return
527 code using the following table. It is OK unless the client is definitely not
528 authorized. This is because CSA is supposed to be optional for sending sites,
529 so recipients should not be too strict about checking it - especially because
530 DNS problems are quite likely to occur. It's possible to use $csa_status in
531 further ACL conditions to distinguish ok, unknown, and defer if required, but
532 the aim is to make the usual configuration simple. */
534 static int csa_return_code[] = {
536 FAIL, FAIL, FAIL, FAIL
539 static uschar *csa_status_string[] = {
540 US"unknown", US"ok", US"defer", US"defer",
541 US"fail", US"fail", US"fail", US"fail"
544 static uschar *csa_reason_string[] = {
547 US"deferred (SRV lookup failed)",
548 US"deferred (target address lookup failed)",
549 US"failed (explicit authorization required)",
550 US"failed (host name not authorized)",
551 US"failed (no authorized addresses)",
552 US"failed (client address mismatch)"
555 /* Options for the ratelimit condition. Note that there are two variants of
556 the per_rcpt option, depending on the ACL that is used to measure the rate.
557 However any ACL must be able to look up per_rcpt rates in /noupdate mode,
558 so the two variants must have the same internal representation as well as
559 the same configuration string. */
562 RATE_PER_WHAT, RATE_PER_CLASH, RATE_PER_ADDR, RATE_PER_BYTE, RATE_PER_CMD,
563 RATE_PER_CONN, RATE_PER_MAIL, RATE_PER_RCPT, RATE_PER_ALLRCPTS
566 #define RATE_SET(var,new) \
567 (((var) == RATE_PER_WHAT) ? ((var) = RATE_##new) : ((var) = RATE_PER_CLASH))
569 static uschar *ratelimit_option_string[] = {
570 US"?", US"!", US"per_addr", US"per_byte", US"per_cmd",
571 US"per_conn", US"per_mail", US"per_rcpt", US"per_rcpt"
574 /* Enable recursion between acl_check_internal() and acl_check_condition() */
576 static int acl_check_wargs(int, address_item *, const uschar *, uschar **,
580 /*************************************************
581 * Find control in list *
582 *************************************************/
584 /* The lists are always in order, so binary chop can be used.
587 name the control name to search for
588 ol the first entry in the control list
589 last one more than the offset of the last entry in the control list
591 Returns: index of a control entry, or -1 if not found
595 find_control(const uschar * name, control_def * ol, int last)
600 int middle = (first + last)/2;
601 uschar * s = ol[middle].name;
602 int c = Ustrncmp(name, s, Ustrlen(s));
603 if (c == 0) return middle;
604 else if (c > 0) first = middle + 1;
612 /*************************************************
613 * Pick out condition from list *
614 *************************************************/
616 /* Use a binary chop method
620 list list of conditions
623 Returns: offset in list, or -1 if not found
627 acl_checkcondition(uschar * name, condition_def * list, int end)
632 int mid = (start + end)/2;
633 int c = Ustrcmp(name, list[mid].name);
634 if (c == 0) return mid;
635 if (c < 0) end = mid;
636 else start = mid + 1;
642 /*************************************************
643 * Pick out name from list *
644 *************************************************/
646 /* Use a binary chop method
653 Returns: offset in list, or -1 if not found
657 acl_checkname(uschar *name, uschar **list, int end)
663 int mid = (start + end)/2;
664 int c = Ustrcmp(name, list[mid]);
665 if (c == 0) return mid;
666 if (c < 0) end = mid; else start = mid + 1;
673 /*************************************************
674 * Read and parse one ACL *
675 *************************************************/
677 /* This function is called both from readconf in order to parse the ACLs in the
678 configuration file, and also when an ACL is encountered dynamically (e.g. as
679 the result of an expansion). It is given a function to call in order to
680 retrieve the lines of the ACL. This function handles skipping comments and
681 blank lines (where relevant).
684 func function to get next line of ACL
685 error where to put an error message
687 Returns: pointer to ACL, or NULL
688 NULL can be legal (empty ACL); in this case error will be NULL
692 acl_read(uschar *(*func)(void), uschar **error)
694 acl_block *yield = NULL;
695 acl_block **lastp = &yield;
696 acl_block *this = NULL;
697 acl_condition_block *cond;
698 acl_condition_block **condp = NULL;
703 while ((s = (*func)()) != NULL)
706 BOOL negated = FALSE;
707 uschar *saveline = s;
710 /* Conditions (but not verbs) are allowed to be negated by an initial
713 while (isspace(*s)) s++;
720 /* Read the name of a verb or a condition, or the start of a new ACL, which
721 can be started by a name, or by a macro definition. */
723 s = readconf_readname(name, sizeof(name), s);
724 if (*s == ':' || (isupper(name[0]) && *s == '=')) return yield;
726 /* If a verb is unrecognized, it may be another condition or modifier that
727 continues the previous verb. */
729 if ((v = acl_checkname(name, verbs, nelem(verbs))) < 0)
733 *error = string_sprintf("unknown ACL verb \"%s\" in \"%s\"", name,
745 *error = string_sprintf("malformed ACL line \"%s\"", saveline);
748 this = store_get(sizeof(acl_block));
750 lastp = &(this->next);
753 this->condition = NULL;
754 condp = &(this->condition);
755 if (*s == 0) continue; /* No condition on this line */
761 s = readconf_readname(name, sizeof(name), s); /* Condition name */
764 /* Handle a condition or modifier. */
766 if ((c = acl_checkcondition(name, conditions, nelem(conditions))) < 0)
768 *error = string_sprintf("unknown ACL condition/modifier in \"%s\"",
773 /* The modifiers may not be negated */
775 if (negated && conditions[c].is_modifier)
777 *error = string_sprintf("ACL error: negation is not allowed with "
778 "\"%s\"", conditions[c].name);
782 /* ENDPASS may occur only with ACCEPT or DISCARD. */
784 if (c == ACLC_ENDPASS &&
785 this->verb != ACL_ACCEPT &&
786 this->verb != ACL_DISCARD)
788 *error = string_sprintf("ACL error: \"%s\" is not allowed with \"%s\"",
789 conditions[c].name, verbs[this->verb]);
793 cond = store_get(sizeof(acl_condition_block));
796 cond->u.negated = negated;
799 condp = &(cond->next);
801 /* The "set" modifier is different in that its argument is "name=value"
802 rather than just a value, and we can check the validity of the name, which
803 gives us a variable name to insert into the data block. The original ACL
804 variable names were acl_c0 ... acl_c9 and acl_m0 ... acl_m9. This was
805 extended to 20 of each type, but after that people successfully argued for
806 arbitrary names. In the new scheme, the names must start with acl_c or acl_m.
807 After that, we allow alphanumerics and underscores, but the first character
808 after c or m must be a digit or an underscore. This retains backwards
815 if (Ustrncmp(s, "acl_c", 5) != 0 &&
816 Ustrncmp(s, "acl_m", 5) != 0)
818 *error = string_sprintf("invalid variable name after \"set\" in ACL "
819 "modifier \"set %s\" (must start \"acl_c\" or \"acl_m\")", s);
824 if (!isdigit(*endptr) && *endptr != '_')
826 *error = string_sprintf("invalid variable name after \"set\" in ACL "
827 "modifier \"set %s\" (digit or underscore must follow acl_c or acl_m)",
832 while (*endptr != 0 && *endptr != '=' && !isspace(*endptr))
834 if (!isalnum(*endptr) && *endptr != '_')
836 *error = string_sprintf("invalid character \"%c\" in variable name "
837 "in ACL modifier \"set %s\"", *endptr, s);
843 cond->u.varname = string_copyn(s + 4, endptr - s - 4);
845 while (isspace(*s)) s++;
848 /* For "set", we are now positioned for the data. For the others, only
849 "endpass" has no data */
851 if (c != ACLC_ENDPASS)
855 *error = string_sprintf("\"=\" missing after ACL \"%s\" %s", name,
856 conditions[c].is_modifier ? US"modifier" : US"condition");
859 while (isspace(*s)) s++;
860 cond->arg = string_copy(s);
869 /*************************************************
870 * Set up added header line(s) *
871 *************************************************/
873 /* This function is called by the add_header modifier, and also from acl_warn()
874 to implement the now-deprecated way of adding header lines using "message" on a
875 "warn" verb. The argument is treated as a sequence of header lines which are
876 added to a chain, provided there isn't an identical one already there.
878 Argument: string of header lines
883 setup_header(const uschar *hstring)
886 int hlen = Ustrlen(hstring);
888 /* Ignore any leading newlines */
889 while (*hstring == '\n') hstring++, hlen--;
891 /* An empty string does nothing; ensure exactly one final newline. */
892 if (hlen <= 0) return;
893 if (hstring[--hlen] != '\n') /* no newline */
894 q = string_sprintf("%s\n", hstring);
895 else if (hstring[hlen-1] == '\n') /* double newline */
897 uschar * s = string_copy(hstring);
898 while(s[--hlen] == '\n')
905 /* Loop for multiple header lines, taking care about continuations */
907 for (p = q; *p != 0; )
911 int newtype = htype_add_bot;
912 header_line **hptr = &acl_added_headers;
914 /* Find next header line within the string */
918 q = Ustrchr(q, '\n'); /* we know there was a newline */
919 if (*(++q) != ' ' && *q != '\t') break;
922 /* If the line starts with a colon, interpret the instruction for where to
923 add it. This temporarily sets up a new type. */
927 if (strncmpic(p, US":after_received:", 16) == 0)
929 newtype = htype_add_rec;
932 else if (strncmpic(p, US":at_start_rfc:", 14) == 0)
934 newtype = htype_add_rfc;
937 else if (strncmpic(p, US":at_start:", 10) == 0)
939 newtype = htype_add_top;
942 else if (strncmpic(p, US":at_end:", 8) == 0)
944 newtype = htype_add_bot;
947 while (*p == ' ' || *p == '\t') p++;
950 /* See if this line starts with a header name, and if not, add X-ACL-Warn:
951 to the front of it. */
953 for (s = p; s < q - 1; s++)
955 if (*s == ':' || !isgraph(*s)) break;
958 hdr = string_sprintf("%s%.*s", (*s == ':')? "" : "X-ACL-Warn: ", (int) (q - p), p);
961 /* See if this line has already been added */
963 while (*hptr != NULL)
965 if (Ustrncmp((*hptr)->text, hdr, hlen) == 0) break;
966 hptr = &((*hptr)->next);
969 /* Add if not previously present */
973 header_line *h = store_get(sizeof(header_line));
982 /* Advance for next header line within the string */
990 /*************************************************
991 * List the added header lines *
992 *************************************************/
999 header_line * h = acl_added_headers;
1003 if (!h) return NULL;
1008 while ((cp = Ustrchr(s, '\n')) != NULL)
1010 if (cp[1] == '\0') break;
1012 /* contains embedded newline; needs doubling */
1013 ret = string_catn(ret, &size, &ptr, s, cp-s+1);
1014 ret = string_catn(ret, &size, &ptr, US"\n", 1);
1017 /* last bit of header */
1019 ret = string_catn(ret, &size, &ptr, s, cp-s+1); /* newline-sep list */
1021 while((h = h->next));
1023 ret[ptr-1] = '\0'; /* overwrite last newline */
1028 /*************************************************
1029 * Set up removed header line(s) *
1030 *************************************************/
1032 /* This function is called by the remove_header modifier. The argument is
1033 treated as a sequence of header names which are added to a colon separated
1034 list, provided there isn't an identical one already there.
1036 Argument: string of header names
1041 setup_remove_header(const uschar *hnames)
1044 acl_removed_headers = acl_removed_headers
1045 ? string_sprintf("%s : %s", acl_removed_headers, hnames)
1046 : string_copy(hnames);
1051 /*************************************************
1053 *************************************************/
1055 /* This function is called when a WARN verb's conditions are true. It adds to
1056 the message's headers, and/or writes information to the log. In each case, this
1057 only happens once (per message for headers, per connection for log).
1059 ** NOTE: The header adding action using the "message" setting is historic, and
1060 its use is now deprecated. The new add_header modifier should be used instead.
1063 where ACL_WHERE_xxxx indicating which ACL this is
1064 user_message message for adding to headers
1065 log_message message for logging, if different
1071 acl_warn(int where, uschar *user_message, uschar *log_message)
1073 if (log_message != NULL && log_message != user_message)
1076 string_item *logged;
1078 text = string_sprintf("%s Warning: %s", host_and_ident(TRUE),
1079 string_printing(log_message));
1081 /* If a sender verification has failed, and the log message is "sender verify
1082 failed", add the failure message. */
1084 if (sender_verified_failed != NULL &&
1085 sender_verified_failed->message != NULL &&
1086 strcmpic(log_message, US"sender verify failed") == 0)
1087 text = string_sprintf("%s: %s", text, sender_verified_failed->message);
1089 /* Search previously logged warnings. They are kept in malloc
1090 store so they can be freed at the start of a new message. */
1092 for (logged = acl_warn_logged; logged != NULL; logged = logged->next)
1093 if (Ustrcmp(logged->text, text) == 0) break;
1097 int length = Ustrlen(text) + 1;
1098 log_write(0, LOG_MAIN, "%s", text);
1099 logged = store_malloc(sizeof(string_item) + length);
1100 logged->text = (uschar *)logged + sizeof(string_item);
1101 memcpy(logged->text, text, length);
1102 logged->next = acl_warn_logged;
1103 acl_warn_logged = logged;
1107 /* If there's no user message, we are done. */
1109 if (user_message == NULL) return;
1111 /* If this isn't a message ACL, we can't do anything with a user message.
1114 if (where > ACL_WHERE_NOTSMTP)
1116 log_write(0, LOG_MAIN|LOG_PANIC, "ACL \"warn\" with \"message\" setting "
1117 "found in a non-message (%s) ACL: cannot specify header lines here: "
1118 "message ignored", acl_wherenames[where]);
1122 /* The code for setting up header lines is now abstracted into a separate
1123 function so that it can be used for the add_header modifier as well. */
1125 setup_header(user_message);
1130 /*************************************************
1131 * Verify and check reverse DNS *
1132 *************************************************/
1134 /* Called from acl_verify() below. We look up the host name(s) of the client IP
1135 address if this has not yet been done. The host_name_lookup() function checks
1136 that one of these names resolves to an address list that contains the client IP
1137 address, so we don't actually have to do the check here.
1140 user_msgptr pointer for user message
1141 log_msgptr pointer for log message
1143 Returns: OK verification condition succeeded
1144 FAIL verification failed
1145 DEFER there was a problem verifying
1149 acl_verify_reverse(uschar **user_msgptr, uschar **log_msgptr)
1153 user_msgptr = user_msgptr; /* stop compiler warning */
1155 /* Previous success */
1157 if (sender_host_name != NULL) return OK;
1159 /* Previous failure */
1161 if (host_lookup_failed)
1163 *log_msgptr = string_sprintf("host lookup failed%s", host_lookup_msg);
1167 /* Need to do a lookup */
1170 debug_printf_indent("looking up host name to force name/address consistency check\n");
1172 if ((rc = host_name_lookup()) != OK)
1174 *log_msgptr = (rc == DEFER)?
1175 US"host lookup deferred for reverse lookup check"
1177 string_sprintf("host lookup failed for reverse lookup check%s",
1179 return rc; /* DEFER or FAIL */
1182 host_build_sender_fullhost();
1188 /*************************************************
1189 * Check client IP address matches CSA target *
1190 *************************************************/
1192 /* Called from acl_verify_csa() below. This routine scans a section of a DNS
1193 response for address records belonging to the CSA target hostname. The section
1194 is specified by the reset argument, either RESET_ADDITIONAL or RESET_ANSWERS.
1195 If one of the addresses matches the client's IP address, then the client is
1196 authorized by CSA. If there are target IP addresses but none of them match
1197 then the client is using an unauthorized IP address. If there are no target IP
1198 addresses then the client cannot be using an authorized IP address. (This is
1199 an odd configuration - why didn't the SRV record have a weight of 1 instead?)
1202 dnsa the DNS answer block
1203 dnss a DNS scan block for us to use
1204 reset option specifying what portion to scan, as described above
1205 target the target hostname to use for matching RR names
1207 Returns: CSA_OK successfully authorized
1208 CSA_FAIL_MISMATCH addresses found but none matched
1209 CSA_FAIL_NOADDR no target addresses found
1213 acl_verify_csa_address(dns_answer *dnsa, dns_scan *dnss, int reset,
1219 BOOL target_found = FALSE;
1221 for (rr = dns_next_rr(dnsa, dnss, reset);
1223 rr = dns_next_rr(dnsa, dnss, RESET_NEXT))
1225 /* Check this is an address RR for the target hostname. */
1229 && rr->type != T_AAAA
1233 if (strcmpic(target, rr->name) != 0) continue;
1235 target_found = TRUE;
1237 /* Turn the target address RR into a list of textual IP addresses and scan
1238 the list. There may be more than one if it is an A6 RR. */
1240 for (da = dns_address_from_rr(dnsa, rr); da != NULL; da = da->next)
1242 /* If the client IP address matches the target IP address, it's good! */
1244 DEBUG(D_acl) debug_printf_indent("CSA target address is %s\n", da->address);
1246 if (strcmpic(sender_host_address, da->address) == 0) return CSA_OK;
1250 /* If we found some target addresses but none of them matched, the client is
1251 using an unauthorized IP address, otherwise the target has no authorized IP
1254 if (target_found) return CSA_FAIL_MISMATCH;
1255 else return CSA_FAIL_NOADDR;
1260 /*************************************************
1261 * Verify Client SMTP Authorization *
1262 *************************************************/
1264 /* Called from acl_verify() below. This routine calls dns_lookup_special()
1265 to find the CSA SRV record corresponding to the domain argument, or
1266 $sender_helo_name if no argument is provided. It then checks that the
1267 client is authorized, and that its IP address corresponds to the SRV
1268 target's address by calling acl_verify_csa_address() above. The address
1269 should have been returned in the DNS response's ADDITIONAL section, but if
1270 not we perform another DNS lookup to get it.
1273 domain pointer to optional parameter following verify = csa
1275 Returns: CSA_UNKNOWN no valid CSA record found
1276 CSA_OK successfully authorized
1277 CSA_FAIL_* client is definitely not authorized
1278 CSA_DEFER_* there was a DNS problem
1282 acl_verify_csa(const uschar *domain)
1285 const uschar *found;
1286 int priority, weight, port;
1293 /* Work out the domain we are using for the CSA lookup. The default is the
1294 client's HELO domain. If the client has not said HELO, use its IP address
1295 instead. If it's a local client (exim -bs), CSA isn't applicable. */
1297 while (isspace(*domain) && *domain != '\0') ++domain;
1298 if (*domain == '\0') domain = sender_helo_name;
1299 if (domain == NULL) domain = sender_host_address;
1300 if (sender_host_address == NULL) return CSA_UNKNOWN;
1302 /* If we have an address literal, strip off the framing ready for turning it
1303 into a domain. The framing consists of matched square brackets possibly
1304 containing a keyword and a colon before the actual IP address. */
1306 if (domain[0] == '[')
1308 const uschar *start = Ustrchr(domain, ':');
1309 if (start == NULL) start = domain;
1310 domain = string_copyn(start + 1, Ustrlen(start) - 2);
1313 /* Turn domains that look like bare IP addresses into domains in the reverse
1314 DNS. This code also deals with address literals and $sender_host_address. It's
1315 not quite kosher to treat bare domains such as EHLO 192.0.2.57 the same as
1316 address literals, but it's probably the most friendly thing to do. This is an
1317 extension to CSA, so we allow it to be turned off for proper conformance. */
1319 if (string_is_ip_address(domain, NULL) != 0)
1321 if (!dns_csa_use_reverse) return CSA_UNKNOWN;
1322 dns_build_reverse(domain, target);
1326 /* Find out if we've already done the CSA check for this domain. If we have,
1327 return the same result again. Otherwise build a new cached result structure
1328 for this domain. The name is filled in now, and the value is filled in when
1329 we return from this function. */
1331 t = tree_search(csa_cache, domain);
1332 if (t != NULL) return t->data.val;
1334 t = store_get_perm(sizeof(tree_node) + Ustrlen(domain));
1335 Ustrcpy(t->name, domain);
1336 (void)tree_insertnode(&csa_cache, t);
1338 /* Now we are ready to do the actual DNS lookup(s). */
1341 switch (dns_special_lookup(&dnsa, domain, T_CSA, &found))
1343 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1346 return t->data.val = CSA_DEFER_SRV;
1348 /* If we found nothing, the client's authorization is unknown. */
1352 return t->data.val = CSA_UNKNOWN;
1354 /* We got something! Go on to look at the reply in more detail. */
1360 /* Scan the reply for well-formed CSA SRV records. */
1362 for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS);
1364 rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT)) if (rr->type == T_SRV)
1366 const uschar * p = rr->data;
1368 /* Extract the numerical SRV fields (p is incremented) */
1370 GETSHORT(priority, p);
1371 GETSHORT(weight, p);
1375 debug_printf_indent("CSA priority=%d weight=%d port=%d\n", priority, weight, port);
1377 /* Check the CSA version number */
1379 if (priority != 1) continue;
1381 /* If the domain does not have a CSA SRV record of its own (i.e. the domain
1382 found by dns_special_lookup() is a parent of the one we asked for), we check
1383 the subdomain assertions in the port field. At the moment there's only one
1384 assertion: legitimate SMTP clients are all explicitly authorized with CSA
1385 SRV records of their own. */
1387 if (Ustrcmp(found, domain) != 0)
1388 return t->data.val = port & 1 ? CSA_FAIL_EXPLICIT : CSA_UNKNOWN;
1390 /* This CSA SRV record refers directly to our domain, so we check the value
1391 in the weight field to work out the domain's authorization. 0 and 1 are
1392 unauthorized; 3 means the client is authorized but we can't check the IP
1393 address in order to authenticate it, so we treat it as unknown; values
1394 greater than 3 are undefined. */
1396 if (weight < 2) return t->data.val = CSA_FAIL_DOMAIN;
1398 if (weight > 2) continue;
1400 /* Weight == 2, which means the domain is authorized. We must check that the
1401 client's IP address is listed as one of the SRV target addresses. Save the
1402 target hostname then break to scan the additional data for its addresses. */
1404 (void)dn_expand(dnsa.answer, dnsa.answer + dnsa.answerlen, p,
1405 (DN_EXPAND_ARG4_TYPE)target, sizeof(target));
1407 DEBUG(D_acl) debug_printf_indent("CSA target is %s\n", target);
1412 /* If we didn't break the loop then no appropriate records were found. */
1414 if (rr == NULL) return t->data.val = CSA_UNKNOWN;
1416 /* Do not check addresses if the target is ".", in accordance with RFC 2782.
1417 A target of "." indicates there are no valid addresses, so the client cannot
1418 be authorized. (This is an odd configuration because weight=2 target=. is
1419 equivalent to weight=1, but we check for it in order to keep load off the
1420 root name servers.) Note that dn_expand() turns "." into "". */
1422 if (Ustrcmp(target, "") == 0) return t->data.val = CSA_FAIL_NOADDR;
1424 /* Scan the additional section of the CSA SRV reply for addresses belonging
1425 to the target. If the name server didn't return any additional data (e.g.
1426 because it does not fully support SRV records), we need to do another lookup
1427 to obtain the target addresses; otherwise we have a definitive result. */
1429 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ADDITIONAL, target);
1430 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1432 /* The DNS lookup type corresponds to the IP version used by the client. */
1435 if (Ustrchr(sender_host_address, ':') != NULL)
1438 #endif /* HAVE_IPV6 */
1442 lookup_dnssec_authenticated = NULL;
1443 switch (dns_lookup(&dnsa, target, type, NULL))
1445 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1448 return t->data.val = CSA_DEFER_ADDR;
1450 /* If the query succeeded, scan the addresses and return the result. */
1453 rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ANSWERS, target);
1454 if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
1455 /* else fall through */
1457 /* If the target has no IP addresses, the client cannot have an authorized
1458 IP address. However, if the target site uses A6 records (not AAAA records)
1459 we have to do yet another lookup in order to check them. */
1463 return t->data.val = CSA_FAIL_NOADDR;
1469 /*************************************************
1470 * Handle verification (address & other) *
1471 *************************************************/
1473 enum { VERIFY_REV_HOST_LKUP, VERIFY_CERT, VERIFY_HELO, VERIFY_CSA, VERIFY_HDR_SYNTAX,
1474 VERIFY_NOT_BLIND, VERIFY_HDR_SNDR, VERIFY_SNDR, VERIFY_RCPT,
1475 VERIFY_HDR_NAMES_ASCII
1480 unsigned where_allowed; /* bitmap */
1481 BOOL no_options; /* Never has /option(s) following */
1482 unsigned alt_opt_sep; /* >0 Non-/ option separator (custom parser) */
1484 static verify_type_t verify_type_list[] = {
1485 { US"reverse_host_lookup", VERIFY_REV_HOST_LKUP, ~0, FALSE, 0 },
1486 { US"certificate", VERIFY_CERT, ~0, TRUE, 0 },
1487 { US"helo", VERIFY_HELO, ~0, TRUE, 0 },
1488 { US"csa", VERIFY_CSA, ~0, FALSE, 0 },
1489 { US"header_syntax", VERIFY_HDR_SYNTAX, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), TRUE, 0 },
1490 { US"not_blind", VERIFY_NOT_BLIND, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), TRUE, 0 },
1491 { US"header_sender", VERIFY_HDR_SNDR, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), FALSE, 0 },
1492 { US"sender", VERIFY_SNDR, (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)
1493 |(1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP),
1495 { US"recipient", VERIFY_RCPT, (1<<ACL_WHERE_RCPT), FALSE, 0 },
1496 { US"header_names_ascii", VERIFY_HDR_NAMES_ASCII, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), TRUE, 0 }
1500 enum { CALLOUT_DEFER_OK, CALLOUT_NOCACHE, CALLOUT_RANDOM, CALLOUT_USE_SENDER,
1501 CALLOUT_USE_POSTMASTER, CALLOUT_POSTMASTER, CALLOUT_FULLPOSTMASTER,
1502 CALLOUT_MAILFROM, CALLOUT_POSTMASTER_MAILFROM, CALLOUT_MAXWAIT, CALLOUT_CONNECT,
1503 CALLOUT_HOLD, CALLOUT_TIME /* TIME must be last */
1509 BOOL has_option; /* Has =option(s) following */
1510 BOOL timeval; /* Has a time value */
1512 static callout_opt_t callout_opt_list[] = {
1513 { US"defer_ok", CALLOUT_DEFER_OK, 0, FALSE, FALSE },
1514 { US"no_cache", CALLOUT_NOCACHE, vopt_callout_no_cache, FALSE, FALSE },
1515 { US"random", CALLOUT_RANDOM, vopt_callout_random, FALSE, FALSE },
1516 { US"use_sender", CALLOUT_USE_SENDER, vopt_callout_recipsender, FALSE, FALSE },
1517 { US"use_postmaster", CALLOUT_USE_POSTMASTER,vopt_callout_recippmaster, FALSE, FALSE },
1518 { US"postmaster_mailfrom",CALLOUT_POSTMASTER_MAILFROM,0, TRUE, FALSE },
1519 { US"postmaster", CALLOUT_POSTMASTER, 0, FALSE, FALSE },
1520 { US"fullpostmaster", CALLOUT_FULLPOSTMASTER,vopt_callout_fullpm, FALSE, FALSE },
1521 { US"mailfrom", CALLOUT_MAILFROM, 0, TRUE, FALSE },
1522 { US"maxwait", CALLOUT_MAXWAIT, 0, TRUE, TRUE },
1523 { US"connect", CALLOUT_CONNECT, 0, TRUE, TRUE },
1524 { US"hold", CALLOUT_HOLD, vopt_callout_hold, FALSE, FALSE },
1525 { NULL, CALLOUT_TIME, 0, FALSE, TRUE }
1530 /* This function implements the "verify" condition. It is called when
1531 encountered in any ACL, because some tests are almost always permitted. Some
1532 just don't make sense, and always fail (for example, an attempt to test a host
1533 lookup for a non-TCP/IP message). Others are restricted to certain ACLs.
1536 where where called from
1537 addr the recipient address that the ACL is handling, or NULL
1538 arg the argument of "verify"
1539 user_msgptr pointer for user message
1540 log_msgptr pointer for log message
1541 basic_errno where to put verify errno
1543 Returns: OK verification condition succeeded
1544 FAIL verification failed
1545 DEFER there was a problem verifying
1550 acl_verify(int where, address_item *addr, const uschar *arg,
1551 uschar **user_msgptr, uschar **log_msgptr, int *basic_errno)
1555 int callout_overall = -1;
1556 int callout_connect = -1;
1557 int verify_options = 0;
1559 BOOL verify_header_sender = FALSE;
1560 BOOL defer_ok = FALSE;
1561 BOOL callout_defer_ok = FALSE;
1562 BOOL no_details = FALSE;
1563 BOOL success_on_redirect = FALSE;
1564 address_item *sender_vaddr = NULL;
1565 uschar *verify_sender_address = NULL;
1566 uschar *pm_mailfrom = NULL;
1567 uschar *se_mailfrom = NULL;
1569 /* Some of the verify items have slash-separated options; some do not. Diagnose
1570 an error if options are given for items that don't expect them.
1573 uschar *slash = Ustrchr(arg, '/');
1574 const uschar *list = arg;
1575 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
1578 if (ss == NULL) goto BAD_VERIFY;
1580 /* Handle name/address consistency verification in a separate function. */
1582 for (vp= verify_type_list;
1583 (char *)vp < (char *)verify_type_list + sizeof(verify_type_list);
1586 if (vp->alt_opt_sep ? strncmpic(ss, vp->name, vp->alt_opt_sep) == 0
1587 : strcmpic (ss, vp->name) == 0)
1589 if ((char *)vp >= (char *)verify_type_list + sizeof(verify_type_list))
1592 if (vp->no_options && slash != NULL)
1594 *log_msgptr = string_sprintf("unexpected '/' found in \"%s\" "
1595 "(this verify item has no options)", arg);
1598 if (!(vp->where_allowed & (1<<where)))
1600 *log_msgptr = string_sprintf("cannot verify %s in ACL for %s", vp->name, acl_wherenames[where]);
1605 case VERIFY_REV_HOST_LKUP:
1606 if (sender_host_address == NULL) return OK;
1607 if ((rc = acl_verify_reverse(user_msgptr, log_msgptr)) == DEFER)
1608 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size)))
1609 if (strcmpic(ss, US"defer_ok") == 0)
1614 /* TLS certificate verification is done at STARTTLS time; here we just
1615 test whether it was successful or not. (This is for optional verification; for
1616 mandatory verification, the connection doesn't last this long.) */
1618 if (tls_in.certificate_verified) return OK;
1619 *user_msgptr = US"no verified certificate";
1623 /* We can test the result of optional HELO verification that might have
1624 occurred earlier. If not, we can attempt the verification now. */
1626 if (!helo_verified && !helo_verify_failed) smtp_verify_helo();
1627 return helo_verified? OK : FAIL;
1630 /* Do Client SMTP Authorization checks in a separate function, and turn the
1631 result code into user-friendly strings. */
1633 rc = acl_verify_csa(list);
1634 *log_msgptr = *user_msgptr = string_sprintf("client SMTP authorization %s",
1635 csa_reason_string[rc]);
1636 csa_status = csa_status_string[rc];
1637 DEBUG(D_acl) debug_printf_indent("CSA result %s\n", csa_status);
1638 return csa_return_code[rc];
1640 case VERIFY_HDR_SYNTAX:
1641 /* Check that all relevant header lines have the correct syntax. If there is
1642 a syntax error, we return details of the error to the sender if configured to
1643 send out full details. (But a "message" setting on the ACL can override, as
1646 rc = verify_check_headers(log_msgptr);
1647 if (rc != OK && *log_msgptr)
1648 if (smtp_return_error_details)
1649 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1651 acl_verify_message = *log_msgptr;
1654 case VERIFY_HDR_NAMES_ASCII:
1655 /* Check that all header names are true 7 bit strings
1656 See RFC 5322, 2.2. and RFC 6532, 3. */
1658 rc = verify_check_header_names_ascii(log_msgptr);
1659 if (rc != OK && smtp_return_error_details && *log_msgptr != NULL)
1660 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1663 case VERIFY_NOT_BLIND:
1664 /* Check that no recipient of this message is "blind", that is, every envelope
1665 recipient must be mentioned in either To: or Cc:. */
1667 rc = verify_check_notblind();
1670 *log_msgptr = string_sprintf("bcc recipient detected");
1671 if (smtp_return_error_details)
1672 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1676 /* The remaining verification tests check recipient and sender addresses,
1677 either from the envelope or from the header. There are a number of
1678 slash-separated options that are common to all of them. */
1680 case VERIFY_HDR_SNDR:
1681 verify_header_sender = TRUE;
1685 /* In the case of a sender, this can optionally be followed by an address to use
1686 in place of the actual sender (rare special-case requirement). */
1690 verify_sender_address = sender_address;
1693 while (isspace(*s)) s++;
1694 if (*s++ != '=') goto BAD_VERIFY;
1695 while (isspace(*s)) s++;
1696 verify_sender_address = string_copy(s);
1707 /* Remaining items are optional; they apply to sender and recipient
1708 verification, including "header sender" verification. */
1710 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size))
1713 if (strcmpic(ss, US"defer_ok") == 0) defer_ok = TRUE;
1714 else if (strcmpic(ss, US"no_details") == 0) no_details = TRUE;
1715 else if (strcmpic(ss, US"success_on_redirect") == 0) success_on_redirect = TRUE;
1717 /* These two old options are left for backwards compatibility */
1719 else if (strcmpic(ss, US"callout_defer_ok") == 0)
1721 callout_defer_ok = TRUE;
1722 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1725 else if (strcmpic(ss, US"check_postmaster") == 0)
1728 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1731 /* The callout option has a number of sub-options, comma separated */
1733 else if (strncmpic(ss, US"callout", 7) == 0)
1735 callout = CALLOUT_TIMEOUT_DEFAULT;
1739 while (isspace(*ss)) ss++;
1742 const uschar * sublist = ss;
1746 while (isspace(*sublist)) sublist++;
1748 while ((opt = string_nextinlist(&sublist, &optsep, buffer, sizeof(buffer))))
1751 double period = 1.0F;
1753 for (op= callout_opt_list; op->name; op++)
1754 if (strncmpic(opt, op->name, Ustrlen(op->name)) == 0)
1757 verify_options |= op->flag;
1760 opt += Ustrlen(op->name);
1761 while (isspace(*opt)) opt++;
1764 *log_msgptr = string_sprintf("'=' expected after "
1765 "\"%s\" in ACL verify condition \"%s\"", op->name, arg);
1768 while (isspace(*opt)) opt++;
1770 if (op->timeval && (period = readconf_readtime(opt, 0, FALSE)) < 0)
1772 *log_msgptr = string_sprintf("bad time value in ACL condition "
1773 "\"verify %s\"", arg);
1779 case CALLOUT_DEFER_OK: callout_defer_ok = TRUE; break;
1780 case CALLOUT_POSTMASTER: pm_mailfrom = US""; break;
1781 case CALLOUT_FULLPOSTMASTER: pm_mailfrom = US""; break;
1782 case CALLOUT_MAILFROM:
1783 if (!verify_header_sender)
1785 *log_msgptr = string_sprintf("\"mailfrom\" is allowed as a "
1786 "callout option only for verify=header_sender (detected in ACL "
1787 "condition \"%s\")", arg);
1790 se_mailfrom = string_copy(opt);
1792 case CALLOUT_POSTMASTER_MAILFROM: pm_mailfrom = string_copy(opt); break;
1793 case CALLOUT_MAXWAIT: callout_overall = period; break;
1794 case CALLOUT_CONNECT: callout_connect = period; break;
1795 case CALLOUT_TIME: callout = period; break;
1801 *log_msgptr = string_sprintf("'=' expected after \"callout\" in "
1802 "ACL condition \"%s\"", arg);
1808 /* Option not recognized */
1812 *log_msgptr = string_sprintf("unknown option \"%s\" in ACL "
1813 "condition \"verify %s\"", ss, arg);
1818 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster)) ==
1819 (vopt_callout_recipsender|vopt_callout_recippmaster))
1821 *log_msgptr = US"only one of use_sender and use_postmaster can be set "
1822 "for a recipient callout";
1826 /* Handle sender-in-header verification. Default the user message to the log
1827 message if giving out verification details. */
1829 if (verify_header_sender)
1833 if ((rc = verify_check_header_address(user_msgptr, log_msgptr, callout,
1834 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, verify_options,
1837 *basic_errno = verrno;
1838 if (smtp_return_error_details)
1840 if (!*user_msgptr && *log_msgptr)
1841 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1842 if (rc == DEFER) acl_temp_details = TRUE;
1847 /* Handle a sender address. The default is to verify *the* sender address, but
1848 optionally a different address can be given, for special requirements. If the
1849 address is empty, we are dealing with a bounce message that has no sender, so
1850 we cannot do any checking. If the real sender address gets rewritten during
1851 verification (e.g. DNS widening), set the flag to stop it being rewritten again
1852 during message reception.
1854 A list of verified "sender" addresses is kept to try to avoid doing to much
1855 work repetitively when there are multiple recipients in a message and they all
1856 require sender verification. However, when callouts are involved, it gets too
1857 complicated because different recipients may require different callout options.
1858 Therefore, we always do a full sender verify when any kind of callout is
1859 specified. Caching elsewhere, for instance in the DNS resolver and in the
1860 callout handling, should ensure that this is not terribly inefficient. */
1862 else if (verify_sender_address)
1864 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster)))
1866 *log_msgptr = US"use_sender or use_postmaster cannot be used for a "
1867 "sender verify callout";
1871 sender_vaddr = verify_checked_sender(verify_sender_address);
1872 if (sender_vaddr != NULL && /* Previously checked */
1873 callout <= 0) /* No callout needed this time */
1875 /* If the "routed" flag is set, it means that routing worked before, so
1876 this check can give OK (the saved return code value, if set, belongs to a
1877 callout that was done previously). If the "routed" flag is not set, routing
1878 must have failed, so we use the saved return code. */
1880 if (testflag(sender_vaddr, af_verify_routed))
1884 rc = sender_vaddr->special_action;
1885 *basic_errno = sender_vaddr->basic_errno;
1887 HDEBUG(D_acl) debug_printf_indent("using cached sender verify result\n");
1890 /* Do a new verification, and cache the result. The cache is used to avoid
1891 verifying the sender multiple times for multiple RCPTs when callouts are not
1892 specified (see comments above).
1894 The cache is also used on failure to give details in response to the first
1895 RCPT that gets bounced for this reason. However, this can be suppressed by
1896 the no_details option, which sets the flag that says "this detail has already
1897 been sent". The cache normally contains just one address, but there may be
1898 more in esoteric circumstances. */
1903 uschar *save_address_data = deliver_address_data;
1905 sender_vaddr = deliver_make_addr(verify_sender_address, TRUE);
1907 if ((sender_vaddr->prop.utf8_msg = message_smtputf8))
1909 sender_vaddr->prop.utf8_downcvt = message_utf8_downconvert == 1;
1910 sender_vaddr->prop.utf8_downcvt_maybe = message_utf8_downconvert == -1;
1913 if (no_details) setflag(sender_vaddr, af_sverify_told);
1914 if (verify_sender_address[0] != 0)
1916 /* If this is the real sender address, save the unrewritten version
1917 for use later in receive. Otherwise, set a flag so that rewriting the
1918 sender in verify_address() does not update sender_address. */
1920 if (verify_sender_address == sender_address)
1921 sender_address_unrewritten = sender_address;
1923 verify_options |= vopt_fake_sender;
1925 if (success_on_redirect)
1926 verify_options |= vopt_success_on_redirect;
1928 /* The recipient, qualify, and expn options are never set in
1931 rc = verify_address(sender_vaddr, NULL, verify_options, callout,
1932 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, &routed);
1934 HDEBUG(D_acl) debug_printf_indent("----------- end verify ------------\n");
1937 *basic_errno = sender_vaddr->basic_errno;
1941 if (Ustrcmp(sender_vaddr->address, verify_sender_address) != 0)
1942 debug_printf_indent("sender %s verified ok as %s\n",
1943 verify_sender_address, sender_vaddr->address);
1945 debug_printf_indent("sender %s verified ok\n",
1946 verify_sender_address);
1950 rc = OK; /* Null sender */
1952 /* Cache the result code */
1954 if (routed) setflag(sender_vaddr, af_verify_routed);
1955 if (callout > 0) setflag(sender_vaddr, af_verify_callout);
1956 sender_vaddr->special_action = rc;
1957 sender_vaddr->next = sender_verified_list;
1958 sender_verified_list = sender_vaddr;
1960 /* Restore the recipient address data, which might have been clobbered by
1961 the sender verification. */
1963 deliver_address_data = save_address_data;
1966 /* Put the sender address_data value into $sender_address_data */
1968 sender_address_data = sender_vaddr->prop.address_data;
1971 /* A recipient address just gets a straightforward verify; again we must handle
1972 the DEFER overrides. */
1978 if (success_on_redirect)
1979 verify_options |= vopt_success_on_redirect;
1981 /* We must use a copy of the address for verification, because it might
1985 rc = verify_address(&addr2, NULL, verify_options|vopt_is_recipient, callout,
1986 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, NULL);
1987 HDEBUG(D_acl) debug_printf_indent("----------- end verify ------------\n");
1989 *basic_errno = addr2.basic_errno;
1990 *log_msgptr = addr2.message;
1991 *user_msgptr = (addr2.user_message != NULL)?
1992 addr2.user_message : addr2.message;
1994 /* Allow details for temporary error if the address is so flagged. */
1995 if (testflag((&addr2), af_pass_message)) acl_temp_details = TRUE;
1997 /* Make $address_data visible */
1998 deliver_address_data = addr2.prop.address_data;
2001 /* We have a result from the relevant test. Handle defer overrides first. */
2003 if (rc == DEFER && (defer_ok ||
2004 (callout_defer_ok && *basic_errno == ERRNO_CALLOUTDEFER)))
2006 HDEBUG(D_acl) debug_printf_indent("verify defer overridden by %s\n",
2007 defer_ok? "defer_ok" : "callout_defer_ok");
2011 /* If we've failed a sender, set up a recipient message, and point
2012 sender_verified_failed to the address item that actually failed. */
2014 if (rc != OK && verify_sender_address != NULL)
2017 *log_msgptr = *user_msgptr = US"Sender verify failed";
2018 else if (*basic_errno != ERRNO_CALLOUTDEFER)
2019 *log_msgptr = *user_msgptr = US"Could not complete sender verify";
2022 *log_msgptr = US"Could not complete sender verify callout";
2023 *user_msgptr = smtp_return_error_details? sender_vaddr->user_message :
2027 sender_verified_failed = sender_vaddr;
2030 /* Verifying an address messes up the values of $domain and $local_part,
2031 so reset them before returning if this is a RCPT ACL. */
2035 deliver_domain = addr->domain;
2036 deliver_localpart = addr->local_part;
2040 /* Syntax errors in the verify argument come here. */
2043 *log_msgptr = string_sprintf("expected \"sender[=address]\", \"recipient\", "
2044 "\"helo\", \"header_syntax\", \"header_sender\", \"header_names_ascii\" "
2045 "or \"reverse_host_lookup\" at start of ACL condition "
2046 "\"verify %s\"", arg);
2053 /*************************************************
2054 * Check argument for control= modifier *
2055 *************************************************/
2057 /* Called from acl_check_condition() below
2060 arg the argument string for control=
2061 pptr set to point to the terminating character
2062 where which ACL we are in
2063 log_msgptr for error messages
2065 Returns: CONTROL_xxx value
2069 decode_control(const uschar *arg, const uschar **pptr, int where, uschar **log_msgptr)
2074 if ( (idx = find_control(arg, controls_list, nelem(controls_list))) < 0
2075 || ( arg[len = Ustrlen((d = controls_list+idx)->name)] != 0
2076 && (!d->has_option || arg[len] != '/')
2079 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
2080 return CONTROL_ERROR;
2090 /*************************************************
2091 * Return a ratelimit error *
2092 *************************************************/
2094 /* Called from acl_ratelimit() below
2097 log_msgptr for error messages
2098 format format string
2099 ... supplementary arguments
2100 ss ratelimit option name
2101 where ACL_WHERE_xxxx indicating which ACL this is
2107 ratelimit_error(uschar **log_msgptr, const char *format, ...)
2110 uschar buffer[STRING_SPRINTF_BUFFER_SIZE];
2111 va_start(ap, format);
2112 if (!string_vformat(buffer, sizeof(buffer), format, ap))
2113 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
2114 "string_sprintf expansion was longer than " SIZE_T_FMT, sizeof(buffer));
2116 *log_msgptr = string_sprintf(
2117 "error in arguments to \"ratelimit\" condition: %s", buffer);
2124 /*************************************************
2125 * Handle rate limiting *
2126 *************************************************/
2128 /* Called by acl_check_condition() below to calculate the result
2129 of the ACL ratelimit condition.
2131 Note that the return value might be slightly unexpected: if the
2132 sender's rate is above the limit then the result is OK. This is
2133 similar to the dnslists condition, and is so that you can write
2134 ACL clauses like: defer ratelimit = 15 / 1h
2137 arg the option string for ratelimit=
2138 where ACL_WHERE_xxxx indicating which ACL this is
2139 log_msgptr for error messages
2141 Returns: OK - Sender's rate is above limit
2142 FAIL - Sender's rate is below limit
2143 DEFER - Problem opening ratelimit database
2144 ERROR - Syntax error in options.
2148 acl_ratelimit(const uschar *arg, int where, uschar **log_msgptr)
2150 double limit, period, count;
2153 uschar *unique = NULL;
2155 BOOL leaky = FALSE, strict = FALSE, readonly = FALSE;
2156 BOOL noupdate = FALSE, badacl = FALSE;
2157 int mode = RATE_PER_WHAT;
2159 tree_node **anchor, *t;
2160 open_db dbblock, *dbm;
2162 dbdata_ratelimit *dbd;
2163 dbdata_ratelimit_unique *dbdb;
2166 /* Parse the first two options and record their values in expansion
2167 variables. These variables allow the configuration to have informative
2168 error messages based on rate limits obtained from a table lookup. */
2170 /* First is the maximum number of messages per period / maximum burst
2171 size, which must be greater than or equal to zero. Zero is useful for
2172 rate measurement as opposed to rate limiting. */
2174 sender_rate_limit = string_nextinlist(&arg, &sep, NULL, 0);
2175 if (sender_rate_limit == NULL)
2176 return ratelimit_error(log_msgptr, "sender rate limit not set");
2178 limit = Ustrtod(sender_rate_limit, &ss);
2179 if (tolower(*ss) == 'k') { limit *= 1024.0; ss++; }
2180 else if (tolower(*ss) == 'm') { limit *= 1024.0*1024.0; ss++; }
2181 else if (tolower(*ss) == 'g') { limit *= 1024.0*1024.0*1024.0; ss++; }
2183 if (limit < 0.0 || *ss != '\0')
2184 return ratelimit_error(log_msgptr,
2185 "\"%s\" is not a positive number", sender_rate_limit);
2187 /* Second is the rate measurement period / exponential smoothing time
2188 constant. This must be strictly greater than zero, because zero leads to
2189 run-time division errors. */
2191 sender_rate_period = string_nextinlist(&arg, &sep, NULL, 0);
2192 if (sender_rate_period == NULL) period = -1.0;
2193 else period = readconf_readtime(sender_rate_period, 0, FALSE);
2195 return ratelimit_error(log_msgptr,
2196 "\"%s\" is not a time value", sender_rate_period);
2198 /* By default we are counting one of something, but the per_rcpt,
2199 per_byte, and count options can change this. */
2203 /* Parse the other options. */
2205 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2208 if (strcmpic(ss, US"leaky") == 0) leaky = TRUE;
2209 else if (strcmpic(ss, US"strict") == 0) strict = TRUE;
2210 else if (strcmpic(ss, US"noupdate") == 0) noupdate = TRUE;
2211 else if (strcmpic(ss, US"readonly") == 0) readonly = TRUE;
2212 else if (strcmpic(ss, US"per_cmd") == 0) RATE_SET(mode, PER_CMD);
2213 else if (strcmpic(ss, US"per_conn") == 0)
2215 RATE_SET(mode, PER_CONN);
2216 if (where == ACL_WHERE_NOTSMTP || where == ACL_WHERE_NOTSMTP_START)
2219 else if (strcmpic(ss, US"per_mail") == 0)
2221 RATE_SET(mode, PER_MAIL);
2222 if (where > ACL_WHERE_NOTSMTP) badacl = TRUE;
2224 else if (strcmpic(ss, US"per_rcpt") == 0)
2226 /* If we are running in the RCPT ACL, then we'll count the recipients
2227 one by one, but if we are running when we have accumulated the whole
2228 list then we'll add them all in one batch. */
2229 if (where == ACL_WHERE_RCPT)
2230 RATE_SET(mode, PER_RCPT);
2231 else if (where >= ACL_WHERE_PREDATA && where <= ACL_WHERE_NOTSMTP)
2232 RATE_SET(mode, PER_ALLRCPTS), count = (double)recipients_count;
2233 else if (where == ACL_WHERE_MAIL || where > ACL_WHERE_NOTSMTP)
2234 RATE_SET(mode, PER_RCPT), badacl = TRUE;
2236 else if (strcmpic(ss, US"per_byte") == 0)
2238 /* If we have not yet received the message data and there was no SIZE
2239 declaration on the MAIL command, then it's safe to just use a value of
2240 zero and let the recorded rate decay as if nothing happened. */
2241 RATE_SET(mode, PER_MAIL);
2242 if (where > ACL_WHERE_NOTSMTP) badacl = TRUE;
2243 else count = message_size < 0 ? 0.0 : (double)message_size;
2245 else if (strcmpic(ss, US"per_addr") == 0)
2247 RATE_SET(mode, PER_RCPT);
2248 if (where != ACL_WHERE_RCPT) badacl = TRUE, unique = US"*";
2249 else unique = string_sprintf("%s@%s", deliver_localpart, deliver_domain);
2251 else if (strncmpic(ss, US"count=", 6) == 0)
2254 count = Ustrtod(ss+6, &e);
2255 if (count < 0.0 || *e != '\0')
2256 return ratelimit_error(log_msgptr,
2257 "\"%s\" is not a positive number", ss);
2259 else if (strncmpic(ss, US"unique=", 7) == 0)
2260 unique = string_copy(ss + 7);
2261 else if (key == NULL)
2262 key = string_copy(ss);
2264 key = string_sprintf("%s/%s", key, ss);
2267 /* Sanity check. When the badacl flag is set the update mode must either
2268 be readonly (which is the default if it is omitted) or, for backwards
2269 compatibility, a combination of noupdate and strict or leaky. */
2271 if (mode == RATE_PER_CLASH)
2272 return ratelimit_error(log_msgptr, "conflicting per_* options");
2273 if (leaky + strict + readonly > 1)
2274 return ratelimit_error(log_msgptr, "conflicting update modes");
2275 if (badacl && (leaky || strict) && !noupdate)
2276 return ratelimit_error(log_msgptr,
2277 "\"%s\" must not have /leaky or /strict option in %s ACL",
2278 ratelimit_option_string[mode], acl_wherenames[where]);
2280 /* Set the default values of any unset options. In readonly mode we
2281 perform the rate computation without any increment so that its value
2282 decays to eventually allow over-limit senders through. */
2284 if (noupdate) readonly = TRUE, leaky = strict = FALSE;
2285 if (badacl) readonly = TRUE;
2286 if (readonly) count = 0.0;
2287 if (!strict && !readonly) leaky = TRUE;
2288 if (mode == RATE_PER_WHAT) mode = RATE_PER_MAIL;
2290 /* Create the lookup key. If there is no explicit key, use sender_host_address.
2291 If there is no sender_host_address (e.g. -bs or acl_not_smtp) then we simply
2292 omit it. The smoothing constant (sender_rate_period) and the per_xxx options
2293 are added to the key because they alter the meaning of the stored data. */
2296 key = (sender_host_address == NULL)? US"" : sender_host_address;
2298 key = string_sprintf("%s/%s/%s%s",
2300 ratelimit_option_string[mode],
2301 unique == NULL ? "" : "unique/",
2305 debug_printf_indent("ratelimit condition count=%.0f %.1f/%s\n", count, limit, key);
2307 /* See if we have already computed the rate by looking in the relevant tree.
2308 For per-connection rate limiting, store tree nodes and dbdata in the permanent
2309 pool so that they survive across resets. In readonly mode we only remember the
2310 result for the rest of this command in case a later command changes it. After
2311 this bit of logic the code is independent of the per_* mode. */
2313 old_pool = store_pool;
2316 anchor = &ratelimiters_cmd;
2319 anchor = &ratelimiters_conn;
2320 store_pool = POOL_PERM;
2324 case RATE_PER_ALLRCPTS:
2325 anchor = &ratelimiters_mail;
2330 anchor = &ratelimiters_cmd;
2333 anchor = NULL; /* silence an "unused" complaint */
2334 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
2335 "internal ACL error: unknown ratelimit mode %d", mode);
2339 t = tree_search(*anchor, key);
2343 /* The following few lines duplicate some of the code below. */
2344 rc = (dbd->rate < limit)? FAIL : OK;
2345 store_pool = old_pool;
2346 sender_rate = string_sprintf("%.1f", dbd->rate);
2348 debug_printf_indent("ratelimit found pre-computed rate %s\n", sender_rate);
2352 /* We aren't using a pre-computed rate, so get a previously recorded rate
2353 from the database, which will be updated and written back if required. */
2355 dbm = dbfn_open(US"ratelimit", O_RDWR, &dbblock, TRUE);
2358 store_pool = old_pool;
2360 HDEBUG(D_acl) debug_printf_indent("ratelimit database not available\n");
2361 *log_msgptr = US"ratelimit database not available";
2364 dbdb = dbfn_read_with_length(dbm, key, &dbdb_size);
2367 gettimeofday(&tv, NULL);
2371 /* Locate the basic ratelimit block inside the DB data. */
2372 HDEBUG(D_acl) debug_printf_indent("ratelimit found key in database\n");
2375 /* Forget the old Bloom filter if it is too old, so that we count each
2376 repeating event once per period. We don't simply clear and re-use the old
2377 filter because we want its size to change if the limit changes. Note that
2378 we keep the dbd pointer for copying the rate into the new data block. */
2380 if(unique != NULL && tv.tv_sec > dbdb->bloom_epoch + period)
2382 HDEBUG(D_acl) debug_printf_indent("ratelimit discarding old Bloom filter\n");
2388 if(unique != NULL && dbdb_size < sizeof(*dbdb))
2390 HDEBUG(D_acl) debug_printf_indent("ratelimit discarding undersize Bloom filter\n");
2395 /* Allocate a new data block if the database lookup failed
2396 or the Bloom filter passed its age limit. */
2402 /* No Bloom filter. This basic ratelimit block is initialized below. */
2403 HDEBUG(D_acl) debug_printf_indent("ratelimit creating new rate data block\n");
2404 dbdb_size = sizeof(*dbd);
2405 dbdb = store_get(dbdb_size);
2410 HDEBUG(D_acl) debug_printf_indent("ratelimit creating new Bloom filter\n");
2412 /* See the long comment below for an explanation of the magic number 2.
2413 The filter has a minimum size in case the rate limit is very small;
2414 this is determined by the definition of dbdata_ratelimit_unique. */
2416 extra = (int)limit * 2 - sizeof(dbdb->bloom);
2417 if (extra < 0) extra = 0;
2418 dbdb_size = sizeof(*dbdb) + extra;
2419 dbdb = store_get(dbdb_size);
2420 dbdb->bloom_epoch = tv.tv_sec;
2421 dbdb->bloom_size = sizeof(dbdb->bloom) + extra;
2422 memset(dbdb->bloom, 0, dbdb->bloom_size);
2424 /* Preserve any basic ratelimit data (which is our longer-term memory)
2425 by copying it from the discarded block. */
2435 /* If we are counting unique events, find out if this event is new or not.
2436 If the client repeats the event during the current period then it should be
2437 counted. We skip this code in readonly mode for efficiency, because any
2438 changes to the filter will be discarded and because count is already set to
2441 if (unique != NULL && !readonly)
2443 /* We identify unique events using a Bloom filter. (You can find my
2444 notes on Bloom filters at http://fanf.livejournal.com/81696.html)
2445 With the per_addr option, an "event" is a recipient address, though the
2446 user can use the unique option to define their own events. We only count
2447 an event if we have not seen it before.
2449 We size the filter according to the rate limit, which (in leaky mode)
2450 is the limit on the population of the filter. We allow 16 bits of space
2451 per entry (see the construction code above) and we set (up to) 8 of them
2452 when inserting an element (see the loop below). The probability of a false
2453 positive (an event we have not seen before but which we fail to count) is
2457 allzero = exp(-numhash * pop / size)
2458 = exp(-0.5 * pop / limit)
2459 fpr = pow(1 - allzero, numhash)
2461 For senders at the limit the fpr is 0.06% or 1 in 1700
2462 and for senders at half the limit it is 0.0006% or 1 in 170000
2464 In strict mode the Bloom filter can fill up beyond the normal limit, in
2465 which case the false positive rate will rise. This means that the
2466 measured rate for very fast senders can bogusly drop off after a while.
2468 At twice the limit, the fpr is 2.5% or 1 in 40
2469 At four times the limit, it is 31% or 1 in 3.2
2471 It takes ln(pop/limit) periods for an over-limit burst of pop events to
2472 decay below the limit, and if this is more than one then the Bloom filter
2473 will be discarded before the decay gets that far. The false positive rate
2474 at this threshold is 9.3% or 1 in 10.7. */
2477 unsigned n, hash, hinc;
2481 /* Instead of using eight independent hash values, we combine two values
2482 using the formula h1 + n * h2. This does not harm the Bloom filter's
2483 performance, and means the amount of hash we need is independent of the
2484 number of bits we set in the filter. */
2486 md5_start(&md5info);
2487 md5_end(&md5info, unique, Ustrlen(unique), md5sum);
2488 hash = md5sum[0] | md5sum[1] << 8 | md5sum[2] << 16 | md5sum[3] << 24;
2489 hinc = md5sum[4] | md5sum[5] << 8 | md5sum[6] << 16 | md5sum[7] << 24;
2491 /* Scan the bits corresponding to this event. A zero bit means we have
2492 not seen it before. Ensure all bits are set to record this event. */
2494 HDEBUG(D_acl) debug_printf_indent("ratelimit checking uniqueness of %s\n", unique);
2497 for (n = 0; n < 8; n++, hash += hinc)
2499 int bit = 1 << (hash % 8);
2500 int byte = (hash / 8) % dbdb->bloom_size;
2501 if ((dbdb->bloom[byte] & bit) == 0)
2503 dbdb->bloom[byte] |= bit;
2508 /* If this event has occurred before, do not count it. */
2512 HDEBUG(D_acl) debug_printf_indent("ratelimit event found in Bloom filter\n");
2516 HDEBUG(D_acl) debug_printf_indent("ratelimit event added to Bloom filter\n");
2519 /* If there was no previous ratelimit data block for this key, initialize
2520 the new one, otherwise update the block from the database. The initial rate
2521 is what would be computed by the code below for an infinite interval. */
2525 HDEBUG(D_acl) debug_printf_indent("ratelimit initializing new key's rate data\n");
2527 dbd->time_stamp = tv.tv_sec;
2528 dbd->time_usec = tv.tv_usec;
2533 /* The smoothed rate is computed using an exponentially weighted moving
2534 average adjusted for variable sampling intervals. The standard EWMA for
2535 a fixed sampling interval is: f'(t) = (1 - a) * f(t) + a * f'(t - 1)
2536 where f() is the measured value and f'() is the smoothed value.
2538 Old data decays out of the smoothed value exponentially, such that data n
2539 samples old is multiplied by a^n. The exponential decay time constant p
2540 is defined such that data p samples old is multiplied by 1/e, which means
2541 that a = exp(-1/p). We can maintain the same time constant for a variable
2542 sampling interval i by using a = exp(-i/p).
2544 The rate we are measuring is messages per period, suitable for directly
2545 comparing with the limit. The average rate between now and the previous
2546 message is period / interval, which we feed into the EWMA as the sample.
2548 It turns out that the number of messages required for the smoothed rate
2549 to reach the limit when they are sent in a burst is equal to the limit.
2550 This can be seen by analysing the value of the smoothed rate after N
2551 messages sent at even intervals. Let k = (1 - a) * p/i
2553 rate_1 = (1 - a) * p/i + a * rate_0
2555 rate_2 = k + a * rate_1
2556 = k + a * k + a^2 * rate_0
2557 rate_3 = k + a * k + a^2 * k + a^3 * rate_0
2558 rate_N = rate_0 * a^N + k * SUM(x=0..N-1)(a^x)
2559 = rate_0 * a^N + k * (1 - a^N) / (1 - a)
2560 = rate_0 * a^N + p/i * (1 - a^N)
2562 When N is large, a^N -> 0 so rate_N -> p/i as desired.
2564 rate_N = p/i + (rate_0 - p/i) * a^N
2565 a^N = (rate_N - p/i) / (rate_0 - p/i)
2566 N * -i/p = log((rate_N - p/i) / (rate_0 - p/i))
2567 N = p/i * log((rate_0 - p/i) / (rate_N - p/i))
2569 Numerical analysis of the above equation, setting the computed rate to
2570 increase from rate_0 = 0 to rate_N = limit, shows that for large sending
2571 rates, p/i, the number of messages N = limit. So limit serves as both the
2572 maximum rate measured in messages per period, and the maximum number of
2573 messages that can be sent in a fast burst. */
2575 double this_time = (double)tv.tv_sec
2576 + (double)tv.tv_usec / 1000000.0;
2577 double prev_time = (double)dbd->time_stamp
2578 + (double)dbd->time_usec / 1000000.0;
2580 /* We must avoid division by zero, and deal gracefully with the clock going
2581 backwards. If we blunder ahead when time is in reverse then the computed
2582 rate will be bogus. To be safe we clamp interval to a very small number. */
2584 double interval = this_time - prev_time <= 0.0 ? 1e-9
2585 : this_time - prev_time;
2587 double i_over_p = interval / period;
2588 double a = exp(-i_over_p);
2590 /* Combine the instantaneous rate (period / interval) with the previous rate
2591 using the smoothing factor a. In order to measure sized events, multiply the
2592 instantaneous rate by the count of bytes or recipients etc. */
2594 dbd->time_stamp = tv.tv_sec;
2595 dbd->time_usec = tv.tv_usec;
2596 dbd->rate = (1 - a) * count / i_over_p + a * dbd->rate;
2598 /* When events are very widely spaced the computed rate tends towards zero.
2599 Although this is accurate it turns out not to be useful for our purposes,
2600 especially when the first event after a long silence is the start of a spam
2601 run. A more useful model is that the rate for an isolated event should be the
2602 size of the event per the period size, ignoring the lack of events outside
2603 the current period and regardless of where the event falls in the period. So,
2604 if the interval was so long that the calculated rate is unhelpfully small, we
2605 re-initialize the rate. In the absence of higher-rate bursts, the condition
2606 below is true if the interval is greater than the period. */
2608 if (dbd->rate < count) dbd->rate = count;
2611 /* Clients sending at the limit are considered to be over the limit.
2612 This matters for edge cases such as a limit of zero, when the client
2613 should be completely blocked. */
2615 rc = (dbd->rate < limit)? FAIL : OK;
2617 /* Update the state if the rate is low or if we are being strict. If we
2618 are in leaky mode and the sender's rate is too high, we do not update
2619 the recorded rate in order to avoid an over-aggressive sender's retry
2620 rate preventing them from getting any email through. If readonly is set,
2621 neither leaky nor strict are set, so we do not do any updates. */
2623 if ((rc == FAIL && leaky) || strict)
2625 dbfn_write(dbm, key, dbdb, dbdb_size);
2626 HDEBUG(D_acl) debug_printf_indent("ratelimit db updated\n");
2630 HDEBUG(D_acl) debug_printf_indent("ratelimit db not updated: %s\n",
2631 readonly? "readonly mode" : "over the limit, but leaky");
2636 /* Store the result in the tree for future reference. */
2638 t = store_get(sizeof(tree_node) + Ustrlen(key));
2640 Ustrcpy(t->name, key);
2641 (void)tree_insertnode(anchor, t);
2643 /* We create the formatted version of the sender's rate very late in
2644 order to ensure that it is done using the correct storage pool. */
2646 store_pool = old_pool;
2647 sender_rate = string_sprintf("%.1f", dbd->rate);
2650 debug_printf_indent("ratelimit computed rate %s\n", sender_rate);
2657 /*************************************************
2658 * The udpsend ACL modifier *
2659 *************************************************/
2661 /* Called by acl_check_condition() below.
2664 arg the option string for udpsend=
2665 log_msgptr for error messages
2667 Returns: OK - Completed.
2668 DEFER - Problem with DNS lookup.
2669 ERROR - Syntax error in options.
2673 acl_udpsend(const uschar *arg, uschar **log_msgptr)
2685 hostname = string_nextinlist(&arg, &sep, NULL, 0);
2686 portstr = string_nextinlist(&arg, &sep, NULL, 0);
2690 *log_msgptr = US"missing destination host in \"udpsend\" modifier";
2695 *log_msgptr = US"missing destination port in \"udpsend\" modifier";
2700 *log_msgptr = US"missing datagram payload in \"udpsend\" modifier";
2703 portnum = Ustrtol(portstr, &portend, 10);
2704 if (*portend != '\0')
2706 *log_msgptr = US"bad destination port in \"udpsend\" modifier";
2710 /* Make a single-item host list. */
2711 h = store_get(sizeof(host_item));
2712 memset(h, 0, sizeof(host_item));
2717 if (string_is_ip_address(hostname, NULL))
2718 h->address = hostname, r = HOST_FOUND;
2720 r = host_find_byname(h, NULL, 0, NULL, FALSE);
2721 if (r == HOST_FIND_FAILED || r == HOST_FIND_AGAIN)
2723 *log_msgptr = US"DNS lookup failed in \"udpsend\" modifier";
2728 debug_printf_indent("udpsend [%s]:%d %s\n", h->address, portnum, arg);
2730 r = s = ip_connectedsocket(SOCK_DGRAM, h->address, portnum, portnum,
2732 if (r < 0) goto defer;
2734 r = send(s, arg, len, 0);
2737 errstr = US strerror(errno);
2745 string_sprintf("\"udpsend\" truncated from %d to %d octets", len, r);
2750 debug_printf_indent("udpsend %d bytes\n", r);
2755 *log_msgptr = string_sprintf("\"udpsend\" failed: %s", errstr);
2761 /*************************************************
2762 * Handle conditions/modifiers on an ACL item *
2763 *************************************************/
2765 /* Called from acl_check() below.
2769 cb ACL condition block - if NULL, result is OK
2770 where where called from
2771 addr the address being checked for RCPT, or NULL
2772 level the nesting level
2773 epp pointer to pass back TRUE if "endpass" encountered
2774 (applies only to "accept" and "discard")
2775 user_msgptr user message pointer
2776 log_msgptr log message pointer
2777 basic_errno pointer to where to put verify error
2779 Returns: OK - all conditions are met
2780 DISCARD - an "acl" condition returned DISCARD - only allowed
2781 for "accept" or "discard" verbs
2782 FAIL - at least one condition fails
2783 FAIL_DROP - an "acl" condition returned FAIL_DROP
2784 DEFER - can't tell at the moment (typically, lookup defer,
2785 but can be temporary callout problem)
2786 ERROR - ERROR from nested ACL or expansion failure or other
2791 acl_check_condition(int verb, acl_condition_block *cb, int where,
2792 address_item *addr, int level, BOOL *epp, uschar **user_msgptr,
2793 uschar **log_msgptr, int *basic_errno)
2795 uschar *user_message = NULL;
2796 uschar *log_message = NULL;
2798 #ifdef WITH_CONTENT_SCAN
2802 for (; cb != NULL; cb = cb->next)
2807 /* The message and log_message items set up messages to be used in
2808 case of rejection. They are expanded later. */
2810 if (cb->type == ACLC_MESSAGE)
2812 HDEBUG(D_acl) debug_printf_indent(" message: %s\n", cb->arg);
2813 user_message = cb->arg;
2817 if (cb->type == ACLC_LOG_MESSAGE)
2819 HDEBUG(D_acl) debug_printf_indent("l_message: %s\n", cb->arg);
2820 log_message = cb->arg;
2824 /* The endpass "condition" just sets a flag to show it occurred. This is
2825 checked at compile time to be on an "accept" or "discard" item. */
2827 if (cb->type == ACLC_ENDPASS)
2833 /* For other conditions and modifiers, the argument is expanded now for some
2834 of them, but not for all, because expansion happens down in some lower level
2835 checking functions in some cases. */
2837 if (!conditions[cb->type].expand_at_top)
2839 else if (!(arg = expand_string(cb->arg)))
2841 if (expand_string_forcedfail) continue;
2842 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s",
2843 cb->arg, expand_string_message);
2844 return search_find_defer ? DEFER : ERROR;
2847 /* Show condition, and expanded condition if it's different */
2852 debug_printf_indent("check %s%s %n",
2853 (!conditions[cb->type].is_modifier && cb->u.negated)? "!":"",
2854 conditions[cb->type].name, &lhswidth);
2856 if (cb->type == ACLC_SET)
2858 debug_printf("acl_%s ", cb->u.varname);
2859 lhswidth += 5 + Ustrlen(cb->u.varname);
2862 debug_printf("= %s\n", cb->arg);
2865 debug_printf("%.*s= %s\n", lhswidth,
2869 /* Check that this condition makes sense at this time */
2871 if ((conditions[cb->type].forbids & (1 << where)) != 0)
2873 *log_msgptr = string_sprintf("cannot %s %s condition in %s ACL",
2874 conditions[cb->type].is_modifier ? "use" : "test",
2875 conditions[cb->type].name, acl_wherenames[where]);
2879 /* Run the appropriate test for each condition, or take the appropriate
2880 action for the remaining modifiers. */
2884 case ACLC_ADD_HEADER:
2888 /* A nested ACL that returns "discard" makes sense only for an "accept" or
2892 rc = acl_check_wargs(where, addr, arg, user_msgptr, log_msgptr);
2893 if (rc == DISCARD && verb != ACL_ACCEPT && verb != ACL_DISCARD)
2895 *log_msgptr = string_sprintf("nested ACL returned \"discard\" for "
2896 "\"%s\" command (only allowed with \"accept\" or \"discard\")",
2902 case ACLC_AUTHENTICATED:
2903 rc = (sender_host_authenticated == NULL)? FAIL :
2904 match_isinlist(sender_host_authenticated, &arg, 0, NULL, NULL, MCL_STRING,
2908 #ifdef EXPERIMENTAL_BRIGHTMAIL
2909 case ACLC_BMI_OPTIN:
2911 int old_pool = store_pool;
2912 store_pool = POOL_PERM;
2913 bmi_current_optin = string_copy(arg);
2914 store_pool = old_pool;
2919 case ACLC_CONDITION:
2920 /* The true/false parsing here should be kept in sync with that used in
2921 expand.c when dealing with ECOND_BOOL so that we don't have too many
2922 different definitions of what can be a boolean. */
2924 ? Ustrspn(arg+1, "0123456789") == Ustrlen(arg+1) /* Negative number */
2925 : Ustrspn(arg, "0123456789") == Ustrlen(arg)) /* Digits, or empty */
2926 rc = (Uatoi(arg) == 0)? FAIL : OK;
2928 rc = (strcmpic(arg, US"no") == 0 ||
2929 strcmpic(arg, US"false") == 0)? FAIL :
2930 (strcmpic(arg, US"yes") == 0 ||
2931 strcmpic(arg, US"true") == 0)? OK : DEFER;
2933 *log_msgptr = string_sprintf("invalid \"condition\" value \"%s\"", arg);
2936 case ACLC_CONTINUE: /* Always succeeds */
2941 const uschar *p = NULL;
2942 control_type = decode_control(arg, &p, where, log_msgptr);
2944 /* Check if this control makes sense at this time */
2946 if (controls_list[control_type].forbids & (1 << where))
2948 *log_msgptr = string_sprintf("cannot use \"control=%s\" in %s ACL",
2949 controls_list[control_type].name, acl_wherenames[where]);
2953 switch(control_type)
2955 case CONTROL_AUTH_UNADVERTISED:
2956 allow_auth_unadvertised = TRUE;
2959 #ifdef EXPERIMENTAL_BRIGHTMAIL
2960 case CONTROL_BMI_RUN:
2965 #ifndef DISABLE_DKIM
2966 case CONTROL_DKIM_VERIFY:
2967 dkim_disable_verify = TRUE;
2968 #ifdef EXPERIMENTAL_DMARC
2969 /* Since DKIM was blocked, skip DMARC too */
2970 dmarc_disable_verify = TRUE;
2971 dmarc_enable_forensic = FALSE;
2976 #ifdef EXPERIMENTAL_DMARC
2977 case CONTROL_DMARC_VERIFY:
2978 dmarc_disable_verify = TRUE;
2981 case CONTROL_DMARC_FORENSIC:
2982 dmarc_enable_forensic = TRUE;
2989 int fd, af, level, optname, value;
2990 /* If we are acting on stdin, the setsockopt may fail if stdin is not
2991 a socket; we can accept that, we'll just debug-log failures anyway. */
2992 fd = fileno(smtp_in);
2993 af = ip_get_address_family(fd);
2997 debug_printf_indent("smtp input is probably not a socket [%s], not setting DSCP\n",
3001 if (dscp_lookup(p+1, af, &level, &optname, &value))
3003 if (setsockopt(fd, level, optname, &value, sizeof(value)) < 0)
3005 HDEBUG(D_acl) debug_printf_indent("failed to set input DSCP[%s]: %s\n",
3006 p+1, strerror(errno));
3010 HDEBUG(D_acl) debug_printf_indent("set input DSCP to \"%s\"\n", p+1);
3015 *log_msgptr = string_sprintf("unrecognised DSCP value in \"control=%s\"", arg);
3021 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3029 case CONTROL_CASEFUL_LOCAL_PART:
3030 deliver_localpart = addr->cc_local_part;
3033 case CONTROL_CASELOWER_LOCAL_PART:
3034 deliver_localpart = addr->lc_local_part;
3037 case CONTROL_ENFORCE_SYNC:
3038 smtp_enforce_sync = TRUE;
3041 case CONTROL_NO_ENFORCE_SYNC:
3042 smtp_enforce_sync = FALSE;
3045 #ifdef WITH_CONTENT_SCAN
3046 case CONTROL_NO_MBOX_UNSPOOL:
3047 no_mbox_unspool = TRUE;
3051 case CONTROL_NO_MULTILINE:
3052 no_multiline_responses = TRUE;
3055 case CONTROL_NO_PIPELINING:
3056 pipelining_enable = FALSE;
3059 case CONTROL_NO_DELAY_FLUSH:
3060 disable_delay_flush = TRUE;
3063 case CONTROL_NO_CALLOUT_FLUSH:
3064 disable_callout_flush = TRUE;
3067 case CONTROL_FAKEREJECT:
3068 cancel_cutthrough_connection(TRUE, US"fakereject");
3069 case CONTROL_FAKEDEFER:
3070 fake_response = (control_type == CONTROL_FAKEDEFER) ? DEFER : FAIL;
3073 const uschar *pp = p + 1;
3074 while (*pp != 0) pp++;
3075 fake_response_text = expand_string(string_copyn(p+1, pp-p-1));
3080 /* Explicitly reset to default string */
3081 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).";
3085 case CONTROL_FREEZE:
3086 deliver_freeze = TRUE;
3087 deliver_frozen_at = time(NULL);
3088 freeze_tell = freeze_tell_config; /* Reset to configured value */
3089 if (Ustrncmp(p, "/no_tell", 8) == 0)
3096 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3099 cancel_cutthrough_connection(TRUE, US"item frozen");
3102 case CONTROL_QUEUE_ONLY:
3103 queue_only_policy = TRUE;
3104 cancel_cutthrough_connection(TRUE, US"queueing forced");
3107 case CONTROL_SUBMISSION:
3108 originator_name = US"";
3109 submission_mode = TRUE;
3112 if (Ustrncmp(p, "/sender_retain", 14) == 0)
3115 active_local_sender_retain = TRUE;
3116 active_local_from_check = FALSE;
3118 else if (Ustrncmp(p, "/domain=", 8) == 0)
3120 const uschar *pp = p + 8;
3121 while (*pp != 0 && *pp != '/') pp++;
3122 submission_domain = string_copyn(p+8, pp-p-8);
3125 /* The name= option must be last, because it swallows the rest of
3127 else if (Ustrncmp(p, "/name=", 6) == 0)
3129 const uschar *pp = p + 6;
3130 while (*pp != 0) pp++;
3131 submission_name = string_copy(parse_fix_phrase(p+6, pp-p-6,
3132 big_buffer, big_buffer_size));
3139 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3146 uschar * debug_tag = NULL;
3147 uschar * debug_opts = NULL;
3152 const uschar * pp = p+1;
3153 if (Ustrncmp(pp, "tag=", 4) == 0)
3155 for (pp += 4; *pp && *pp != '/';) pp++;
3156 debug_tag = string_copyn(p+5, pp-p-5);
3158 else if (Ustrncmp(pp, "opts=", 5) == 0)
3160 for (pp += 5; *pp && *pp != '/';) pp++;
3161 debug_opts = string_copyn(p+6, pp-p-6);
3163 else if (Ustrncmp(pp, "kill", 4) == 0)
3165 for (pp += 4; *pp && *pp != '/';) pp++;
3169 while (*pp && *pp != '/') pp++;
3174 debug_logging_stop();
3176 debug_logging_activate(debug_tag, debug_opts);
3180 case CONTROL_SUPPRESS_LOCAL_FIXUPS:
3181 suppress_local_fixups = TRUE;
3184 case CONTROL_CUTTHROUGH_DELIVERY:
3185 #ifndef DISABLE_PRDR
3190 /* Too hard to think about for now. We might in future cutthrough
3191 the case where both sides handle prdr and this-node prdr acl
3193 *log_msgptr = string_sprintf("PRDR on %s reception\n", arg);
3197 *log_msgptr = US"frozen";
3198 else if (queue_only_policy)
3199 *log_msgptr = US"queue-only";
3200 else if (fake_response == FAIL)
3201 *log_msgptr = US"fakereject";
3204 if (rcpt_count == 1)
3206 cutthrough.delivery = TRUE;
3209 const uschar * pp = p+1;
3210 if (Ustrncmp(pp, "defer=", 6) == 0)
3213 if (Ustrncmp(pp, "pass", 4) == 0) cutthrough.defer_pass = TRUE;
3214 /* else if (Ustrncmp(pp, "spool") == 0) ; default */
3217 while (*pp && *pp != '/') pp++;
3223 *log_msgptr = string_sprintf("\"control=%s\" on %s item",
3229 case CONTROL_UTF8_DOWNCONVERT:
3234 message_utf8_downconvert = 1;
3235 addr->prop.utf8_downcvt = TRUE;
3236 addr->prop.utf8_downcvt_maybe = FALSE;
3242 message_utf8_downconvert = 0;
3243 addr->prop.utf8_downcvt = FALSE;
3244 addr->prop.utf8_downcvt_maybe = FALSE;
3248 if (p[1] == '-' && p[2] == '1')
3250 message_utf8_downconvert = -1;
3251 addr->prop.utf8_downcvt = FALSE;
3252 addr->prop.utf8_downcvt_maybe = TRUE;
3256 *log_msgptr = US"bad option value for control=utf8_downconvert";
3260 message_utf8_downconvert = 1;
3261 addr->prop.utf8_downcvt = TRUE;
3262 addr->prop.utf8_downcvt_maybe = FALSE;
3272 #ifdef EXPERIMENTAL_DCC
3275 /* Separate the regular expression and any optional parameters. */
3276 const uschar * list = arg;
3277 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
3278 /* Run the dcc backend. */
3279 rc = dcc_process(&ss);
3280 /* Modify return code based upon the existence of options. */
3281 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size)))
3282 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
3283 rc = FAIL; /* FAIL so that the message is passed to the next ACL */
3288 #ifdef WITH_CONTENT_SCAN
3290 rc = mime_decode(&arg);
3296 int delay = readconf_readtime(arg, 0, FALSE);
3299 *log_msgptr = string_sprintf("syntax error in argument for \"delay\" "
3300 "modifier: \"%s\" is not a time value", arg);
3305 HDEBUG(D_acl) debug_printf_indent("delay modifier requests %d-second delay\n",
3310 debug_printf_indent("delay skipped in -bh checking mode\n");
3313 /* NOTE 1: Remember that we may be
3314 dealing with stdin/stdout here, in addition to TCP/IP connections.
3315 Also, delays may be specified for non-SMTP input, where smtp_out and
3316 smtp_in will be NULL. Whatever is done must work in all cases.
3318 NOTE 2: The added feature of flushing the output before a delay must
3319 apply only to SMTP input. Hence the test for smtp_out being non-NULL.
3324 if (smtp_out != NULL && !disable_delay_flush)
3327 #if !defined(NO_POLL_H) && defined (POLLRDHUP)
3333 p.fd = fileno(smtp_out);
3334 p.events = POLLRDHUP;
3337 if (poll(&p, n, delay*1000) > 0)
3338 HDEBUG(D_acl) debug_printf_indent("delay cancelled by peer close\n");
3341 /* It appears to be impossible to detect that a TCP/IP connection has
3342 gone away without reading from it. This means that we cannot shorten
3343 the delay below if the client goes away, because we cannot discover
3344 that the client has closed its end of the connection. (The connection
3345 is actually in a half-closed state, waiting for the server to close its
3346 end.) It would be nice to be able to detect this state, so that the
3347 Exim process is not held up unnecessarily. However, it seems that we
3348 can't. The poll() function does not do the right thing, and in any case
3349 it is not always available.
3352 while (delay > 0) delay = sleep(delay);
3359 #ifndef DISABLE_DKIM
3360 case ACLC_DKIM_SIGNER:
3361 if (dkim_cur_signer != NULL)
3362 rc = match_isinlist(dkim_cur_signer,
3363 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
3368 case ACLC_DKIM_STATUS:
3369 rc = match_isinlist(dkim_exim_expand_query(DKIM_VERIFY_STATUS),
3370 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
3374 #ifdef EXPERIMENTAL_DMARC
3375 case ACLC_DMARC_STATUS:
3376 if (!dmarc_has_been_checked)
3378 dmarc_has_been_checked = TRUE;
3379 /* used long way of dmarc_exim_expand_query() in case we need more
3380 * view into the process in the future. */
3381 rc = match_isinlist(dmarc_exim_expand_query(DMARC_VERIFY_STATUS),
3382 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
3387 rc = verify_check_dnsbl(where, &arg, log_msgptr);
3391 rc = match_isinlist(addr->domain, &arg, 0, &domainlist_anchor,
3392 addr->domain_cache, MCL_DOMAIN, TRUE, CUSS &deliver_domain_data);
3395 /* The value in tls_cipher is the full cipher name, for example,
3396 TLSv1:DES-CBC3-SHA:168, whereas the values to test for are just the
3397 cipher names such as DES-CBC3-SHA. But program defensively. We don't know
3398 what may in practice come out of the SSL library - which at the time of
3399 writing is poorly documented. */
3401 case ACLC_ENCRYPTED:
3402 if (tls_in.cipher == NULL) rc = FAIL; else
3404 uschar *endcipher = NULL;
3405 uschar *cipher = Ustrchr(tls_in.cipher, ':');
3406 if (cipher == NULL) cipher = tls_in.cipher; else
3408 endcipher = Ustrchr(++cipher, ':');
3409 if (endcipher != NULL) *endcipher = 0;
3411 rc = match_isinlist(cipher, &arg, 0, NULL, NULL, MCL_STRING, TRUE, NULL);
3412 if (endcipher != NULL) *endcipher = ':';
3416 /* Use verify_check_this_host() instead of verify_check_host() so that
3417 we can pass over &host_data to catch any looked up data. Once it has been
3418 set, it retains its value so that it's still there if another ACL verb
3419 comes through here and uses the cache. However, we must put it into
3420 permanent store in case it is also expected to be used in a subsequent
3421 message in the same SMTP connection. */
3424 rc = verify_check_this_host(&arg, sender_host_cache, NULL,
3425 (sender_host_address == NULL)? US"" : sender_host_address,
3427 if (rc == DEFER) *log_msgptr = search_error_message;
3428 if (host_data) host_data = string_copy_malloc(host_data);
3431 case ACLC_LOCAL_PARTS:
3432 rc = match_isinlist(addr->cc_local_part, &arg, 0,
3433 &localpartlist_anchor, addr->localpart_cache, MCL_LOCALPART, TRUE,
3434 CUSS &deliver_localpart_data);
3437 case ACLC_LOG_REJECT_TARGET:
3441 const uschar *s = arg;
3443 while ((ss = string_nextinlist(&s, &sep, big_buffer, big_buffer_size)))
3445 if (Ustrcmp(ss, "main") == 0) logbits |= LOG_MAIN;
3446 else if (Ustrcmp(ss, "panic") == 0) logbits |= LOG_PANIC;
3447 else if (Ustrcmp(ss, "reject") == 0) logbits |= LOG_REJECT;
3450 logbits |= LOG_MAIN|LOG_REJECT;
3451 log_write(0, LOG_MAIN|LOG_PANIC, "unknown log name \"%s\" in "
3452 "\"log_reject_target\" in %s ACL", ss, acl_wherenames[where]);
3455 log_reject_target = logbits;
3462 const uschar *s = arg;
3468 if (Ustrncmp(s, "main", 4) == 0)
3469 { logbits |= LOG_MAIN; s += 4; }
3470 else if (Ustrncmp(s, "panic", 5) == 0)
3471 { logbits |= LOG_PANIC; s += 5; }
3472 else if (Ustrncmp(s, "reject", 6) == 0)
3473 { logbits |= LOG_REJECT; s += 6; }
3476 logbits = LOG_MAIN|LOG_PANIC;
3477 s = string_sprintf(":unknown log name in \"%s\" in "
3478 "\"logwrite\" in %s ACL", arg, acl_wherenames[where]);
3484 while (isspace(*s)) s++;
3487 if (logbits == 0) logbits = LOG_MAIN;
3488 log_write(0, logbits, "%s", string_printing(s));
3492 #ifdef WITH_CONTENT_SCAN
3493 case ACLC_MALWARE: /* Run the malware backend. */
3495 /* Separate the regular expression and any optional parameters. */
3496 const uschar * list = arg;
3497 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
3499 BOOL defer_ok = FALSE;
3502 while ((opt = string_nextinlist(&list, &sep, NULL, 0)))
3503 if (strcmpic(opt, US"defer_ok") == 0)
3505 else if ( strncmpic(opt, US"tmo=", 4) == 0
3506 && (timeout = readconf_readtime(opt+4, '\0', FALSE)) < 0
3509 *log_msgptr = string_sprintf("bad timeout value in '%s'", opt);
3513 rc = malware(ss, timeout);
3514 if (rc == DEFER && defer_ok)
3515 rc = FAIL; /* FAIL so that the message is passed to the next ACL */
3519 case ACLC_MIME_REGEX:
3520 rc = mime_regex(&arg);
3525 queue_name = string_copy_malloc(arg);
3528 case ACLC_RATELIMIT:
3529 rc = acl_ratelimit(arg, where, log_msgptr);
3532 case ACLC_RECIPIENTS:
3533 rc = match_address_list(CUS addr->address, TRUE, TRUE, &arg, NULL, -1, 0,
3534 CUSS &recipient_data);
3537 #ifdef WITH_CONTENT_SCAN
3543 case ACLC_REMOVE_HEADER:
3544 setup_remove_header(arg);
3547 case ACLC_SENDER_DOMAINS:
3550 sdomain = Ustrrchr(sender_address, '@');
3551 sdomain = sdomain ? sdomain + 1 : US"";
3552 rc = match_isinlist(sdomain, &arg, 0, &domainlist_anchor,
3553 sender_domain_cache, MCL_DOMAIN, TRUE, NULL);
3558 rc = match_address_list(CUS sender_address, TRUE, TRUE, &arg,
3559 sender_address_cache, -1, 0, CUSS &sender_data);
3562 /* Connection variables must persist forever */
3566 int old_pool = store_pool;
3567 if ( cb->u.varname[0] == 'c'
3568 #ifndef DISABLE_EVENT
3569 || event_name /* An event is being delivered */
3572 store_pool = POOL_PERM;
3573 acl_var_create(cb->u.varname)->data.ptr = string_copy(arg);
3574 store_pool = old_pool;
3578 #ifdef WITH_CONTENT_SCAN
3581 /* Separate the regular expression and any optional parameters. */
3582 const uschar * list = arg;
3583 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
3584 /* Run the spam backend. */
3585 rc = spam(CUSS &ss);
3586 /* Modify return code based upon the existence of options. */
3587 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size))
3589 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
3591 /* FAIL so that the message is passed to the next ACL */
3599 #ifdef EXPERIMENTAL_SPF
3601 rc = spf_process(&arg, sender_address, SPF_PROCESS_NORMAL);
3603 case ACLC_SPF_GUESS:
3604 rc = spf_process(&arg, sender_address, SPF_PROCESS_GUESS);
3609 rc = acl_udpsend(arg, log_msgptr);
3612 /* If the verb is WARN, discard any user message from verification, because
3613 such messages are SMTP responses, not header additions. The latter come
3614 only from explicit "message" modifiers. However, put the user message into
3615 $acl_verify_message so it can be used in subsequent conditions or modifiers
3616 (until something changes it). */
3619 rc = acl_verify(where, addr, arg, user_msgptr, log_msgptr, basic_errno);
3621 acl_verify_message = *user_msgptr;
3622 if (verb == ACL_WARN) *user_msgptr = NULL;
3626 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown "
3627 "condition %d", cb->type);
3631 /* If a condition was negated, invert OK/FAIL. */
3633 if (!conditions[cb->type].is_modifier && cb->u.negated)
3634 if (rc == OK) rc = FAIL;
3635 else if (rc == FAIL || rc == FAIL_DROP) rc = OK;
3637 if (rc != OK) break; /* Conditions loop */
3641 /* If the result is the one for which "message" and/or "log_message" are used,
3642 handle the values of these modifiers. If there isn't a log message set, we make
3643 it the same as the user message.
3645 "message" is a user message that will be included in an SMTP response. Unless
3646 it is empty, it overrides any previously set user message.
3648 "log_message" is a non-user message, and it adds to any existing non-user
3649 message that is already set.
3651 Most verbs have but a single return for which the messages are relevant, but
3652 for "discard", it's useful to have the log message both when it succeeds and
3653 when it fails. For "accept", the message is used in the OK case if there is no
3654 "endpass", but (for backwards compatibility) in the FAIL case if "endpass" is
3657 if (*epp && rc == OK) user_message = NULL;
3659 if (((1<<rc) & msgcond[verb]) != 0)
3662 uschar *old_user_msgptr = *user_msgptr;
3663 uschar *old_log_msgptr = (*log_msgptr != NULL)? *log_msgptr : old_user_msgptr;
3665 /* If the verb is "warn", messages generated by conditions (verification or
3666 nested ACLs) are always discarded. This also happens for acceptance verbs
3667 when they actually do accept. Only messages specified at this level are used.
3668 However, the value of an existing message is available in $acl_verify_message
3669 during expansions. */
3671 if (verb == ACL_WARN ||
3672 (rc == OK && (verb == ACL_ACCEPT || verb == ACL_DISCARD)))
3673 *log_msgptr = *user_msgptr = NULL;
3675 if (user_message != NULL)
3677 acl_verify_message = old_user_msgptr;
3678 expmessage = expand_string(user_message);
3679 if (expmessage == NULL)
3681 if (!expand_string_forcedfail)
3682 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
3683 user_message, expand_string_message);
3685 else if (expmessage[0] != 0) *user_msgptr = expmessage;
3688 if (log_message != NULL)
3690 acl_verify_message = old_log_msgptr;
3691 expmessage = expand_string(log_message);
3692 if (expmessage == NULL)
3694 if (!expand_string_forcedfail)
3695 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
3696 log_message, expand_string_message);
3698 else if (expmessage[0] != 0)
3700 *log_msgptr = (*log_msgptr == NULL)? expmessage :
3701 string_sprintf("%s: %s", expmessage, *log_msgptr);
3705 /* If no log message, default it to the user message */
3707 if (*log_msgptr == NULL) *log_msgptr = *user_msgptr;
3710 acl_verify_message = NULL;
3718 /*************************************************
3719 * Get line from a literal ACL *
3720 *************************************************/
3722 /* This function is passed to acl_read() in order to extract individual lines
3723 of a literal ACL, which we access via static pointers. We can destroy the
3724 contents because this is called only once (the compiled ACL is remembered).
3726 This code is intended to treat the data in the same way as lines in the main
3727 Exim configuration file. That is:
3729 . Leading spaces are ignored.
3731 . A \ at the end of a line is a continuation - trailing spaces after the \
3732 are permitted (this is because I don't believe in making invisible things
3733 significant). Leading spaces on the continued part of a line are ignored.
3735 . Physical lines starting (significantly) with # are totally ignored, and
3736 may appear within a sequence of backslash-continued lines.
3738 . Blank lines are ignored, but will end a sequence of continuations.
3741 Returns: a pointer to the next line
3745 static uschar *acl_text; /* Current pointer in the text */
3746 static uschar *acl_text_end; /* Points one past the terminating '0' */
3754 /* This loop handles leading blank lines and comments. */
3758 while (isspace(*acl_text)) acl_text++; /* Leading spaces/empty lines */
3759 if (*acl_text == 0) return NULL; /* No more data */
3760 yield = acl_text; /* Potential data line */
3762 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3764 /* If we hit the end before a newline, we have the whole logical line. If
3765 it's a comment, there's no more data to be given. Otherwise, yield it. */
3767 if (*acl_text == 0) return (*yield == '#')? NULL : yield;
3769 /* After reaching a newline, end this loop if the physical line does not
3770 start with '#'. If it does, it's a comment, and the loop continues. */
3772 if (*yield != '#') break;
3775 /* This loop handles continuations. We know we have some real data, ending in
3776 newline. See if there is a continuation marker at the end (ignoring trailing
3777 white space). We know that *yield is not white space, so no need to test for
3778 cont > yield in the backwards scanning loop. */
3783 for (cont = acl_text - 1; isspace(*cont); cont--);
3785 /* If no continuation follows, we are done. Mark the end of the line and
3794 /* We have encountered a continuation. Skip over whitespace at the start of
3795 the next line, and indeed the whole of the next line or lines if they are
3800 while (*(++acl_text) == ' ' || *acl_text == '\t');
3801 if (*acl_text != '#') break;
3802 while (*(++acl_text) != 0 && *acl_text != '\n');
3805 /* We have the start of a continuation line. Move all the rest of the data
3806 to join onto the previous line, and then find its end. If the end is not a
3807 newline, we are done. Otherwise loop to look for another continuation. */
3809 memmove(cont, acl_text, acl_text_end - acl_text);
3810 acl_text_end -= acl_text - cont;
3812 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3813 if (*acl_text == 0) return yield;
3816 /* Control does not reach here */
3823 /*************************************************
3824 * Check access using an ACL *
3825 *************************************************/
3827 /* This function is called from address_check. It may recurse via
3828 acl_check_condition() - hence the use of a level to stop looping. The ACL is
3829 passed as a string which is expanded. A forced failure implies no access check
3830 is required. If the result is a single word, it is taken as the name of an ACL
3831 which is sought in the global ACL tree. Otherwise, it is taken as literal ACL
3832 text, complete with newlines, and parsed as such. In both cases, the ACL check
3833 is then run. This function uses an auxiliary function for acl_read() to call
3834 for reading individual lines of a literal ACL. This is acl_getline(), which
3835 appears immediately above.
3838 where where called from
3839 addr address item when called from RCPT; otherwise NULL
3840 s the input string; NULL is the same as an empty ACL => DENY
3841 user_msgptr where to put a user error (for SMTP response)
3842 log_msgptr where to put a logging message (not for SMTP response)
3844 Returns: OK access is granted
3845 DISCARD access is apparently granted...
3846 FAIL access is denied
3847 FAIL_DROP access is denied; drop the connection
3848 DEFER can't tell at the moment
3853 acl_check_internal(int where, address_item *addr, uschar *s,
3854 uschar **user_msgptr, uschar **log_msgptr)
3857 acl_block *acl = NULL;
3858 uschar *acl_name = US"inline ACL";
3861 /* Catch configuration loops */
3865 *log_msgptr = US"ACL nested too deep: possible loop";
3871 HDEBUG(D_acl) debug_printf_indent("ACL is NULL: implicit DENY\n");
3875 /* At top level, we expand the incoming string. At lower levels, it has already
3876 been expanded as part of condition processing. */
3880 if (!(ss = expand_string(s)))
3882 if (expand_string_forcedfail) return OK;
3883 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s", s,
3884 expand_string_message);
3890 while (isspace(*ss))ss++;
3892 /* If we can't find a named ACL, the default is to parse it as an inline one.
3893 (Unless it begins with a slash; non-existent files give rise to an error.) */
3897 /* Handle the case of a string that does not contain any spaces. Look for a
3898 named ACL among those read from the configuration, or a previously read file.
3899 It is possible that the pointer to the ACL is NULL if the configuration
3900 contains a name with no data. If not found, and the text begins with '/',
3901 read an ACL from a file, and save it so it can be re-used. */
3903 if (Ustrchr(ss, ' ') == NULL)
3905 tree_node *t = tree_search(acl_anchor, ss);
3908 acl = (acl_block *)(t->data.ptr);
3911 HDEBUG(D_acl) debug_printf_indent("ACL \"%s\" is empty: implicit DENY\n", ss);
3914 acl_name = string_sprintf("ACL \"%s\"", ss);
3915 HDEBUG(D_acl) debug_printf_indent("using ACL \"%s\"\n", ss);
3918 else if (*ss == '/')
3920 struct stat statbuf;
3921 fd = Uopen(ss, O_RDONLY, 0);
3924 *log_msgptr = string_sprintf("failed to open ACL file \"%s\": %s", ss,
3929 if (fstat(fd, &statbuf) != 0)
3931 *log_msgptr = string_sprintf("failed to fstat ACL file \"%s\": %s", ss,
3936 acl_text = store_get(statbuf.st_size + 1);
3937 acl_text_end = acl_text + statbuf.st_size + 1;
3939 if (read(fd, acl_text, statbuf.st_size) != statbuf.st_size)
3941 *log_msgptr = string_sprintf("failed to read ACL file \"%s\": %s",
3942 ss, strerror(errno));
3945 acl_text[statbuf.st_size] = 0;
3948 acl_name = string_sprintf("ACL \"%s\"", ss);
3949 HDEBUG(D_acl) debug_printf_indent("read ACL from file %s\n", ss);
3953 /* Parse an ACL that is still in text form. If it came from a file, remember it
3954 in the ACL tree, having read it into the POOL_PERM store pool so that it
3955 persists between multiple messages. */
3959 int old_pool = store_pool;
3960 if (fd >= 0) store_pool = POOL_PERM;
3961 acl = acl_read(acl_getline, log_msgptr);
3962 store_pool = old_pool;
3963 if (acl == NULL && *log_msgptr != NULL) return ERROR;
3966 tree_node *t = store_get_perm(sizeof(tree_node) + Ustrlen(ss));
3967 Ustrcpy(t->name, ss);
3969 (void)tree_insertnode(&acl_anchor, t);
3973 /* Now we have an ACL to use. It's possible it may be NULL. */
3978 int basic_errno = 0;
3979 BOOL endpass_seen = FALSE;
3980 BOOL acl_quit_check = acl_level == 0
3981 && (where == ACL_WHERE_QUIT || where == ACL_WHERE_NOTQUIT);
3983 *log_msgptr = *user_msgptr = NULL;
3984 acl_temp_details = FALSE;
3986 HDEBUG(D_acl) debug_printf_indent("processing \"%s\"\n", verbs[acl->verb]);
3988 /* Clear out any search error message from a previous check before testing
3991 search_error_message = NULL;
3992 cond = acl_check_condition(acl->verb, acl->condition, where, addr, acl_level,
3993 &endpass_seen, user_msgptr, log_msgptr, &basic_errno);
3995 /* Handle special returns: DEFER causes a return except on a WARN verb;
3996 ERROR always causes a return. */
4001 HDEBUG(D_acl) debug_printf_indent("%s: condition test deferred in %s\n", verbs[acl->verb], acl_name);
4002 if (basic_errno != ERRNO_CALLOUTDEFER)
4004 if (search_error_message != NULL && *search_error_message != 0)
4005 *log_msgptr = search_error_message;
4006 if (smtp_return_error_details) acl_temp_details = TRUE;
4010 acl_temp_details = TRUE;
4012 if (acl->verb != ACL_WARN) return DEFER;
4015 default: /* Paranoia */
4017 HDEBUG(D_acl) debug_printf_indent("%s: condition test error in %s\n", verbs[acl->verb], acl_name);
4021 HDEBUG(D_acl) debug_printf_indent("%s: condition test succeeded in %s\n",
4022 verbs[acl->verb], acl_name);
4026 HDEBUG(D_acl) debug_printf_indent("%s: condition test failed in %s\n", verbs[acl->verb], acl_name);
4029 /* DISCARD and DROP can happen only from a nested ACL condition, and
4030 DISCARD can happen only for an "accept" or "discard" verb. */
4033 HDEBUG(D_acl) debug_printf_indent("%s: condition test yielded \"discard\" in %s\n",
4034 verbs[acl->verb], acl_name);
4038 HDEBUG(D_acl) debug_printf_indent("%s: condition test yielded \"drop\" in %s\n",
4039 verbs[acl->verb], acl_name);
4043 /* At this point, cond for most verbs is either OK or FAIL or (as a result of
4044 a nested ACL condition) FAIL_DROP. However, for WARN, cond may be DEFER, and
4045 for ACCEPT and DISCARD, it may be DISCARD after a nested ACL call. */
4050 if (cond == OK || cond == DISCARD)
4052 HDEBUG(D_acl) debug_printf_indent("end of %s: ACCEPT\n", acl_name);
4057 HDEBUG(D_acl) debug_printf_indent("accept: endpass encountered - denying access\n");
4065 HDEBUG(D_acl) debug_printf_indent("end of %s: DEFER\n", acl_name);
4066 if (acl_quit_check) goto badquit;
4067 acl_temp_details = TRUE;
4075 HDEBUG(D_acl) debug_printf_indent("end of %s: DENY\n", acl_name);
4076 if (acl_quit_check) goto badquit;
4082 if (cond == OK || cond == DISCARD)
4084 HDEBUG(D_acl) debug_printf_indent("end of %s: DISCARD\n", acl_name);
4085 if (acl_quit_check) goto badquit;
4090 HDEBUG(D_acl) debug_printf_indent("discard: endpass encountered - denying access\n");
4098 HDEBUG(D_acl) debug_printf_indent("end of %s: DROP\n", acl_name);
4099 if (acl_quit_check) goto badquit;
4107 HDEBUG(D_acl) debug_printf_indent("end of %s: not OK\n", acl_name);
4108 if (acl_quit_check) goto badquit;
4115 acl_warn(where, *user_msgptr, *log_msgptr);
4116 else if (cond == DEFER && LOGGING(acl_warn_skipped))
4117 log_write(0, LOG_MAIN, "%s Warning: ACL \"warn\" statement skipped: "
4118 "condition test deferred%s%s", host_and_ident(TRUE),
4119 (*log_msgptr == NULL)? US"" : US": ",
4120 (*log_msgptr == NULL)? US"" : *log_msgptr);
4121 *log_msgptr = *user_msgptr = NULL; /* In case implicit DENY follows */
4125 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown verb %d",
4130 /* Pass to the next ACL item */
4135 /* We have reached the end of the ACL. This is an implicit DENY. */
4137 HDEBUG(D_acl) debug_printf_indent("end of %s: implicit DENY\n", acl_name);
4141 *log_msgptr = string_sprintf("QUIT or not-QUIT toplevel ACL may not fail "
4142 "('%s' verb used incorrectly)", verbs[acl->verb]);
4149 /* Same args as acl_check_internal() above, but the string s is
4150 the name of an ACL followed optionally by up to 9 space-separated arguments.
4151 The name and args are separately expanded. Args go into $acl_arg globals. */
4153 acl_check_wargs(int where, address_item *addr, const uschar *s,
4154 uschar **user_msgptr, uschar **log_msgptr)
4157 uschar * tmp_arg[9]; /* must match acl_arg[] */
4158 uschar * sav_arg[9]; /* must match acl_arg[] */
4164 if (!(tmp = string_dequote(&s)) || !(name = expand_string(tmp)))
4167 for (i = 0; i < 9; i++)
4169 while (*s && isspace(*s)) s++;
4171 if (!(tmp = string_dequote(&s)) || !(tmp_arg[i] = expand_string(tmp)))
4178 sav_narg = acl_narg;
4180 for (i = 0; i < acl_narg; i++)
4182 sav_arg[i] = acl_arg[i];
4183 acl_arg[i] = tmp_arg[i];
4187 sav_arg[i] = acl_arg[i];
4188 acl_arg[i++] = NULL;
4192 ret = acl_check_internal(where, addr, name, user_msgptr, log_msgptr);
4195 acl_narg = sav_narg;
4196 for (i = 0; i < 9; i++) acl_arg[i] = sav_arg[i];
4200 if (expand_string_forcedfail) return ERROR;
4201 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s",
4202 tmp, expand_string_message);
4203 return search_find_defer?DEFER:ERROR;
4208 /*************************************************
4209 * Check access using an ACL *
4210 *************************************************/
4212 /* Alternate interface for ACL, used by expansions */
4214 acl_eval(int where, uschar *s, uschar **user_msgptr, uschar **log_msgptr)
4217 address_item *addr = NULL;
4220 *user_msgptr = *log_msgptr = NULL;
4221 sender_verified_failed = NULL;
4222 ratelimiters_cmd = NULL;
4223 log_reject_target = LOG_MAIN|LOG_REJECT;
4225 if (where == ACL_WHERE_RCPT)
4227 adb = address_defaults;
4229 addr->address = expand_string(US"$local_part@$domain");
4230 addr->domain = deliver_domain;
4231 addr->local_part = deliver_localpart;
4232 addr->cc_local_part = deliver_localpart;
4233 addr->lc_local_part = deliver_localpart;
4237 rc = acl_check_internal(where, addr, s, user_msgptr, log_msgptr);
4244 /* This is the external interface for ACL checks. It sets up an address and the
4245 expansions for $domain and $local_part when called after RCPT, then calls
4246 acl_check_internal() to do the actual work.
4249 where ACL_WHERE_xxxx indicating where called from
4250 recipient RCPT address for RCPT check, else NULL
4251 s the input string; NULL is the same as an empty ACL => DENY
4252 user_msgptr where to put a user error (for SMTP response)
4253 log_msgptr where to put a logging message (not for SMTP response)
4255 Returns: OK access is granted by an ACCEPT verb
4256 DISCARD access is granted by a DISCARD verb
4257 FAIL access is denied
4258 FAIL_DROP access is denied; drop the connection
4259 DEFER can't tell at the moment
4262 int acl_where = ACL_WHERE_UNKNOWN;
4265 acl_check(int where, uschar *recipient, uschar *s, uschar **user_msgptr,
4266 uschar **log_msgptr)
4270 address_item *addr = NULL;
4272 *user_msgptr = *log_msgptr = NULL;
4273 sender_verified_failed = NULL;
4274 ratelimiters_cmd = NULL;
4275 log_reject_target = LOG_MAIN|LOG_REJECT;
4277 #ifndef DISABLE_PRDR
4278 if (where==ACL_WHERE_RCPT || where==ACL_WHERE_VRFY || where==ACL_WHERE_PRDR)
4280 if (where==ACL_WHERE_RCPT || where==ACL_WHERE_VRFY)
4283 adb = address_defaults;
4285 addr->address = recipient;
4286 if (deliver_split_address(addr) == DEFER)
4288 *log_msgptr = US"defer in percent_hack_domains check";
4292 if ((addr->prop.utf8_msg = message_smtputf8))
4294 addr->prop.utf8_downcvt = message_utf8_downconvert == 1;
4295 addr->prop.utf8_downcvt_maybe = message_utf8_downconvert == -1;
4298 deliver_domain = addr->domain;
4299 deliver_localpart = addr->local_part;
4304 rc = acl_check_internal(where, addr, s, user_msgptr, log_msgptr);
4306 acl_where = ACL_WHERE_UNKNOWN;
4308 /* Cutthrough - if requested,
4309 and WHERE_RCPT and not yet opened conn as result of recipient-verify,
4310 and rcpt acl returned accept,
4311 and first recipient (cancel on any subsequents)
4312 open one now and run it up to RCPT acceptance.
4313 A failed verify should cancel cutthrough request,
4314 and will pass the fail to the originator.
4315 Initial implementation: dual-write to spool.
4316 Assume the rxd datastream is now being copied byte-for-byte to an open cutthrough connection.
4318 Cease cutthrough copy on rxd final dot; do not send one.
4320 On a data acl, if not accept and a cutthrough conn is open, hard-close it (no SMTP niceness).
4322 On data acl accept, terminate the dataphase on an open cutthrough conn. If accepted or
4323 perm-rejected, reflect that to the original sender - and dump the spooled copy.
4324 If temp-reject, close the conn (and keep the spooled copy).
4325 If conn-failure, no action (and keep the spooled copy).
4329 case ACL_WHERE_RCPT:
4330 #ifndef DISABLE_PRDR
4331 case ACL_WHERE_PRDR:
4334 if (host_checking_callout) /* -bhc mode */
4335 cancel_cutthrough_connection(TRUE, US"host-checking mode");
4338 && cutthrough.delivery
4339 && rcpt_count > cutthrough.nrcpt
4340 && (rc = open_cutthrough_connection(addr)) == DEFER
4342 if (cutthrough.defer_pass)
4344 uschar * s = addr->message;
4345 /* Horrid kludge to recover target's SMTP message */
4347 do --s; while (!isdigit(*s));
4348 if (*--s && isdigit(*s) && *--s && isdigit(*s)) *user_msgptr = s;
4349 acl_temp_details = TRUE;
4353 HDEBUG(D_acl) debug_printf_indent("cutthrough defer; will spool\n");
4358 case ACL_WHERE_PREDATA:
4360 cutthrough_predata();
4362 cancel_cutthrough_connection(TRUE, US"predata acl not ok");
4365 case ACL_WHERE_QUIT:
4366 case ACL_WHERE_NOTQUIT:
4367 /* Drop cutthrough conns, and drop heldopen verify conns if
4368 the previous was not DATA */
4370 uschar prev = smtp_connection_had[smtp_ch_index-2];
4371 BOOL dropverify = !(prev == SCH_DATA || prev == SCH_BDAT);
4373 cancel_cutthrough_connection(dropverify, US"quit or conndrop");
4381 deliver_domain = deliver_localpart = deliver_address_data =
4382 sender_address_data = NULL;
4384 /* A DISCARD response is permitted only for message ACLs, excluding the PREDATA
4385 ACL, which is really in the middle of an SMTP command. */
4389 if (where > ACL_WHERE_NOTSMTP || where == ACL_WHERE_PREDATA)
4391 log_write(0, LOG_MAIN|LOG_PANIC, "\"discard\" verb not allowed in %s "
4392 "ACL", acl_wherenames[where]);
4398 /* A DROP response is not permitted from MAILAUTH */
4400 if (rc == FAIL_DROP && where == ACL_WHERE_MAILAUTH)
4402 log_write(0, LOG_MAIN|LOG_PANIC, "\"drop\" verb not allowed in %s "
4403 "ACL", acl_wherenames[where]);
4407 /* Before giving a response, take a look at the length of any user message, and
4408 split it up into multiple lines if possible. */
4410 *user_msgptr = string_split_message(*user_msgptr);
4411 if (fake_response != OK)
4412 fake_response_text = string_split_message(fake_response_text);
4418 /*************************************************
4419 * Create ACL variable *
4420 *************************************************/
4422 /* Create an ACL variable or reuse an existing one. ACL variables are in a
4423 binary tree (see tree.c) with acl_var_c and acl_var_m as root nodes.
4426 name pointer to the variable's name, starting with c or m
4428 Returns the pointer to variable's tree node
4432 acl_var_create(uschar * name)
4434 tree_node * node, ** root = name[0] == 'c' ? &acl_var_c : &acl_var_m;
4435 if (!(node = tree_search(*root, name)))
4437 node = store_get(sizeof(tree_node) + Ustrlen(name));
4438 Ustrcpy(node->name, name);
4439 (void)tree_insertnode(root, node);
4441 node->data.ptr = NULL;
4447 /*************************************************
4448 * Write an ACL variable in spool format *
4449 *************************************************/
4451 /* This function is used as a callback for tree_walk when writing variables to
4452 the spool file. To retain spool file compatibility, what is written is -aclc or
4453 -aclm followed by the rest of the name and the data length, space separated,
4454 then the value itself, starting on a new line, and terminated by an additional
4455 newline. When we had only numbered ACL variables, the first line might look
4456 like this: "-aclc 5 20". Now it might be "-aclc foo 20" for the variable called
4460 name of the variable
4461 value of the variable
4462 ctx FILE pointer (as a void pointer)
4468 acl_var_write(uschar *name, uschar *value, void *ctx)
4470 FILE *f = (FILE *)ctx;
4471 fprintf(f, "-acl%c %s %d\n%s\n", name[0], name+1, Ustrlen(value), value);