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,
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 { NULL, CALLOUT_TIME, 0, FALSE, TRUE }
1529 /* This function implements the "verify" condition. It is called when
1530 encountered in any ACL, because some tests are almost always permitted. Some
1531 just don't make sense, and always fail (for example, an attempt to test a host
1532 lookup for a non-TCP/IP message). Others are restricted to certain ACLs.
1535 where where called from
1536 addr the recipient address that the ACL is handling, or NULL
1537 arg the argument of "verify"
1538 user_msgptr pointer for user message
1539 log_msgptr pointer for log message
1540 basic_errno where to put verify errno
1542 Returns: OK verification condition succeeded
1543 FAIL verification failed
1544 DEFER there was a problem verifying
1549 acl_verify(int where, address_item *addr, const uschar *arg,
1550 uschar **user_msgptr, uschar **log_msgptr, int *basic_errno)
1554 int callout_overall = -1;
1555 int callout_connect = -1;
1556 int verify_options = 0;
1558 BOOL verify_header_sender = FALSE;
1559 BOOL defer_ok = FALSE;
1560 BOOL callout_defer_ok = FALSE;
1561 BOOL no_details = FALSE;
1562 BOOL success_on_redirect = FALSE;
1563 address_item *sender_vaddr = NULL;
1564 uschar *verify_sender_address = NULL;
1565 uschar *pm_mailfrom = NULL;
1566 uschar *se_mailfrom = NULL;
1568 /* Some of the verify items have slash-separated options; some do not. Diagnose
1569 an error if options are given for items that don't expect them.
1572 uschar *slash = Ustrchr(arg, '/');
1573 const uschar *list = arg;
1574 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
1577 if (ss == NULL) goto BAD_VERIFY;
1579 /* Handle name/address consistency verification in a separate function. */
1581 for (vp= verify_type_list;
1582 (char *)vp < (char *)verify_type_list + sizeof(verify_type_list);
1585 if (vp->alt_opt_sep ? strncmpic(ss, vp->name, vp->alt_opt_sep) == 0
1586 : strcmpic (ss, vp->name) == 0)
1588 if ((char *)vp >= (char *)verify_type_list + sizeof(verify_type_list))
1591 if (vp->no_options && slash != NULL)
1593 *log_msgptr = string_sprintf("unexpected '/' found in \"%s\" "
1594 "(this verify item has no options)", arg);
1597 if (!(vp->where_allowed & (1<<where)))
1599 *log_msgptr = string_sprintf("cannot verify %s in ACL for %s", vp->name, acl_wherenames[where]);
1604 case VERIFY_REV_HOST_LKUP:
1605 if (sender_host_address == NULL) return OK;
1606 if ((rc = acl_verify_reverse(user_msgptr, log_msgptr)) == DEFER)
1607 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size)))
1608 if (strcmpic(ss, US"defer_ok") == 0)
1613 /* TLS certificate verification is done at STARTTLS time; here we just
1614 test whether it was successful or not. (This is for optional verification; for
1615 mandatory verification, the connection doesn't last this long.) */
1617 if (tls_in.certificate_verified) return OK;
1618 *user_msgptr = US"no verified certificate";
1622 /* We can test the result of optional HELO verification that might have
1623 occurred earlier. If not, we can attempt the verification now. */
1625 if (!helo_verified && !helo_verify_failed) smtp_verify_helo();
1626 return helo_verified? OK : FAIL;
1629 /* Do Client SMTP Authorization checks in a separate function, and turn the
1630 result code into user-friendly strings. */
1632 rc = acl_verify_csa(list);
1633 *log_msgptr = *user_msgptr = string_sprintf("client SMTP authorization %s",
1634 csa_reason_string[rc]);
1635 csa_status = csa_status_string[rc];
1636 DEBUG(D_acl) debug_printf_indent("CSA result %s\n", csa_status);
1637 return csa_return_code[rc];
1639 case VERIFY_HDR_SYNTAX:
1640 /* Check that all relevant header lines have the correct syntax. If there is
1641 a syntax error, we return details of the error to the sender if configured to
1642 send out full details. (But a "message" setting on the ACL can override, as
1645 rc = verify_check_headers(log_msgptr);
1646 if (rc != OK && *log_msgptr)
1647 if (smtp_return_error_details)
1648 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1650 acl_verify_message = *log_msgptr;
1653 case VERIFY_HDR_NAMES_ASCII:
1654 /* Check that all header names are true 7 bit strings
1655 See RFC 5322, 2.2. and RFC 6532, 3. */
1657 rc = verify_check_header_names_ascii(log_msgptr);
1658 if (rc != OK && smtp_return_error_details && *log_msgptr != NULL)
1659 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1662 case VERIFY_NOT_BLIND:
1663 /* Check that no recipient of this message is "blind", that is, every envelope
1664 recipient must be mentioned in either To: or Cc:. */
1666 rc = verify_check_notblind();
1669 *log_msgptr = string_sprintf("bcc recipient detected");
1670 if (smtp_return_error_details)
1671 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1675 /* The remaining verification tests check recipient and sender addresses,
1676 either from the envelope or from the header. There are a number of
1677 slash-separated options that are common to all of them. */
1679 case VERIFY_HDR_SNDR:
1680 verify_header_sender = TRUE;
1684 /* In the case of a sender, this can optionally be followed by an address to use
1685 in place of the actual sender (rare special-case requirement). */
1689 verify_sender_address = sender_address;
1692 while (isspace(*s)) s++;
1693 if (*s++ != '=') goto BAD_VERIFY;
1694 while (isspace(*s)) s++;
1695 verify_sender_address = string_copy(s);
1706 /* Remaining items are optional; they apply to sender and recipient
1707 verification, including "header sender" verification. */
1709 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size))
1712 if (strcmpic(ss, US"defer_ok") == 0) defer_ok = TRUE;
1713 else if (strcmpic(ss, US"no_details") == 0) no_details = TRUE;
1714 else if (strcmpic(ss, US"success_on_redirect") == 0) success_on_redirect = TRUE;
1716 /* These two old options are left for backwards compatibility */
1718 else if (strcmpic(ss, US"callout_defer_ok") == 0)
1720 callout_defer_ok = TRUE;
1721 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1724 else if (strcmpic(ss, US"check_postmaster") == 0)
1727 if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
1730 /* The callout option has a number of sub-options, comma separated */
1732 else if (strncmpic(ss, US"callout", 7) == 0)
1734 callout = CALLOUT_TIMEOUT_DEFAULT;
1738 while (isspace(*ss)) ss++;
1741 const uschar * sublist = ss;
1745 while (isspace(*sublist)) sublist++;
1747 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++;
1772 period = readconf_readtime(opt, 0, FALSE);
1775 *log_msgptr = string_sprintf("bad time value in ACL condition "
1776 "\"verify %s\"", arg);
1783 case CALLOUT_DEFER_OK: callout_defer_ok = TRUE; break;
1784 case CALLOUT_POSTMASTER: pm_mailfrom = US""; break;
1785 case CALLOUT_FULLPOSTMASTER: pm_mailfrom = US""; break;
1786 case CALLOUT_MAILFROM:
1787 if (!verify_header_sender)
1789 *log_msgptr = string_sprintf("\"mailfrom\" is allowed as a "
1790 "callout option only for verify=header_sender (detected in ACL "
1791 "condition \"%s\")", arg);
1794 se_mailfrom = string_copy(opt);
1796 case CALLOUT_POSTMASTER_MAILFROM: pm_mailfrom = string_copy(opt); break;
1797 case CALLOUT_MAXWAIT: callout_overall = period; break;
1798 case CALLOUT_CONNECT: callout_connect = period; break;
1799 case CALLOUT_TIME: callout = period; break;
1805 *log_msgptr = string_sprintf("'=' expected after \"callout\" in "
1806 "ACL condition \"%s\"", arg);
1812 /* Option not recognized */
1816 *log_msgptr = string_sprintf("unknown option \"%s\" in ACL "
1817 "condition \"verify %s\"", ss, arg);
1822 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster)) ==
1823 (vopt_callout_recipsender|vopt_callout_recippmaster))
1825 *log_msgptr = US"only one of use_sender and use_postmaster can be set "
1826 "for a recipient callout";
1830 /* Handle sender-in-header verification. Default the user message to the log
1831 message if giving out verification details. */
1833 if (verify_header_sender)
1837 if ((rc = verify_check_header_address(user_msgptr, log_msgptr, callout,
1838 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, verify_options,
1841 *basic_errno = verrno;
1842 if (smtp_return_error_details)
1844 if (!*user_msgptr && *log_msgptr)
1845 *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
1846 if (rc == DEFER) acl_temp_details = TRUE;
1851 /* Handle a sender address. The default is to verify *the* sender address, but
1852 optionally a different address can be given, for special requirements. If the
1853 address is empty, we are dealing with a bounce message that has no sender, so
1854 we cannot do any checking. If the real sender address gets rewritten during
1855 verification (e.g. DNS widening), set the flag to stop it being rewritten again
1856 during message reception.
1858 A list of verified "sender" addresses is kept to try to avoid doing to much
1859 work repetitively when there are multiple recipients in a message and they all
1860 require sender verification. However, when callouts are involved, it gets too
1861 complicated because different recipients may require different callout options.
1862 Therefore, we always do a full sender verify when any kind of callout is
1863 specified. Caching elsewhere, for instance in the DNS resolver and in the
1864 callout handling, should ensure that this is not terribly inefficient. */
1866 else if (verify_sender_address)
1868 if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster)))
1870 *log_msgptr = US"use_sender or use_postmaster cannot be used for a "
1871 "sender verify callout";
1875 sender_vaddr = verify_checked_sender(verify_sender_address);
1876 if (sender_vaddr != NULL && /* Previously checked */
1877 callout <= 0) /* No callout needed this time */
1879 /* If the "routed" flag is set, it means that routing worked before, so
1880 this check can give OK (the saved return code value, if set, belongs to a
1881 callout that was done previously). If the "routed" flag is not set, routing
1882 must have failed, so we use the saved return code. */
1884 if (testflag(sender_vaddr, af_verify_routed))
1888 rc = sender_vaddr->special_action;
1889 *basic_errno = sender_vaddr->basic_errno;
1891 HDEBUG(D_acl) debug_printf_indent("using cached sender verify result\n");
1894 /* Do a new verification, and cache the result. The cache is used to avoid
1895 verifying the sender multiple times for multiple RCPTs when callouts are not
1896 specified (see comments above).
1898 The cache is also used on failure to give details in response to the first
1899 RCPT that gets bounced for this reason. However, this can be suppressed by
1900 the no_details option, which sets the flag that says "this detail has already
1901 been sent". The cache normally contains just one address, but there may be
1902 more in esoteric circumstances. */
1907 uschar *save_address_data = deliver_address_data;
1909 sender_vaddr = deliver_make_addr(verify_sender_address, TRUE);
1911 if ((sender_vaddr->prop.utf8_msg = message_smtputf8))
1913 sender_vaddr->prop.utf8_downcvt = message_utf8_downconvert == 1;
1914 sender_vaddr->prop.utf8_downcvt_maybe = message_utf8_downconvert == -1;
1917 if (no_details) setflag(sender_vaddr, af_sverify_told);
1918 if (verify_sender_address[0] != 0)
1920 /* If this is the real sender address, save the unrewritten version
1921 for use later in receive. Otherwise, set a flag so that rewriting the
1922 sender in verify_address() does not update sender_address. */
1924 if (verify_sender_address == sender_address)
1925 sender_address_unrewritten = sender_address;
1927 verify_options |= vopt_fake_sender;
1929 if (success_on_redirect)
1930 verify_options |= vopt_success_on_redirect;
1932 /* The recipient, qualify, and expn options are never set in
1935 rc = verify_address(sender_vaddr, NULL, verify_options, callout,
1936 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, &routed);
1938 HDEBUG(D_acl) debug_printf_indent("----------- end verify ------------\n");
1941 *basic_errno = sender_vaddr->basic_errno;
1945 if (Ustrcmp(sender_vaddr->address, verify_sender_address) != 0)
1946 debug_printf_indent("sender %s verified ok as %s\n",
1947 verify_sender_address, sender_vaddr->address);
1949 debug_printf_indent("sender %s verified ok\n",
1950 verify_sender_address);
1954 rc = OK; /* Null sender */
1956 /* Cache the result code */
1958 if (routed) setflag(sender_vaddr, af_verify_routed);
1959 if (callout > 0) setflag(sender_vaddr, af_verify_callout);
1960 sender_vaddr->special_action = rc;
1961 sender_vaddr->next = sender_verified_list;
1962 sender_verified_list = sender_vaddr;
1964 /* Restore the recipient address data, which might have been clobbered by
1965 the sender verification. */
1967 deliver_address_data = save_address_data;
1970 /* Put the sender address_data value into $sender_address_data */
1972 sender_address_data = sender_vaddr->prop.address_data;
1975 /* A recipient address just gets a straightforward verify; again we must handle
1976 the DEFER overrides. */
1982 if (success_on_redirect)
1983 verify_options |= vopt_success_on_redirect;
1985 /* We must use a copy of the address for verification, because it might
1989 rc = verify_address(&addr2, NULL, verify_options|vopt_is_recipient, callout,
1990 callout_overall, callout_connect, se_mailfrom, pm_mailfrom, NULL);
1991 HDEBUG(D_acl) debug_printf_indent("----------- end verify ------------\n");
1993 *basic_errno = addr2.basic_errno;
1994 *log_msgptr = addr2.message;
1995 *user_msgptr = (addr2.user_message != NULL)?
1996 addr2.user_message : addr2.message;
1998 /* Allow details for temporary error if the address is so flagged. */
1999 if (testflag((&addr2), af_pass_message)) acl_temp_details = TRUE;
2001 /* Make $address_data visible */
2002 deliver_address_data = addr2.prop.address_data;
2005 /* We have a result from the relevant test. Handle defer overrides first. */
2007 if (rc == DEFER && (defer_ok ||
2008 (callout_defer_ok && *basic_errno == ERRNO_CALLOUTDEFER)))
2010 HDEBUG(D_acl) debug_printf_indent("verify defer overridden by %s\n",
2011 defer_ok? "defer_ok" : "callout_defer_ok");
2015 /* If we've failed a sender, set up a recipient message, and point
2016 sender_verified_failed to the address item that actually failed. */
2018 if (rc != OK && verify_sender_address != NULL)
2021 *log_msgptr = *user_msgptr = US"Sender verify failed";
2022 else if (*basic_errno != ERRNO_CALLOUTDEFER)
2023 *log_msgptr = *user_msgptr = US"Could not complete sender verify";
2026 *log_msgptr = US"Could not complete sender verify callout";
2027 *user_msgptr = smtp_return_error_details? sender_vaddr->user_message :
2031 sender_verified_failed = sender_vaddr;
2034 /* Verifying an address messes up the values of $domain and $local_part,
2035 so reset them before returning if this is a RCPT ACL. */
2039 deliver_domain = addr->domain;
2040 deliver_localpart = addr->local_part;
2044 /* Syntax errors in the verify argument come here. */
2047 *log_msgptr = string_sprintf("expected \"sender[=address]\", \"recipient\", "
2048 "\"helo\", \"header_syntax\", \"header_sender\", \"header_names_ascii\" "
2049 "or \"reverse_host_lookup\" at start of ACL condition "
2050 "\"verify %s\"", arg);
2057 /*************************************************
2058 * Check argument for control= modifier *
2059 *************************************************/
2061 /* Called from acl_check_condition() below
2064 arg the argument string for control=
2065 pptr set to point to the terminating character
2066 where which ACL we are in
2067 log_msgptr for error messages
2069 Returns: CONTROL_xxx value
2073 decode_control(const uschar *arg, const uschar **pptr, int where, uschar **log_msgptr)
2078 if ( (idx = find_control(arg, controls_list, nelem(controls_list))) < 0
2079 || ( arg[len = Ustrlen((d = controls_list+idx)->name)] != 0
2080 && (!d->has_option || arg[len] != '/')
2083 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
2084 return CONTROL_ERROR;
2094 /*************************************************
2095 * Return a ratelimit error *
2096 *************************************************/
2098 /* Called from acl_ratelimit() below
2101 log_msgptr for error messages
2102 format format string
2103 ... supplementary arguments
2104 ss ratelimit option name
2105 where ACL_WHERE_xxxx indicating which ACL this is
2111 ratelimit_error(uschar **log_msgptr, const char *format, ...)
2114 uschar buffer[STRING_SPRINTF_BUFFER_SIZE];
2115 va_start(ap, format);
2116 if (!string_vformat(buffer, sizeof(buffer), format, ap))
2117 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
2118 "string_sprintf expansion was longer than " SIZE_T_FMT, sizeof(buffer));
2120 *log_msgptr = string_sprintf(
2121 "error in arguments to \"ratelimit\" condition: %s", buffer);
2128 /*************************************************
2129 * Handle rate limiting *
2130 *************************************************/
2132 /* Called by acl_check_condition() below to calculate the result
2133 of the ACL ratelimit condition.
2135 Note that the return value might be slightly unexpected: if the
2136 sender's rate is above the limit then the result is OK. This is
2137 similar to the dnslists condition, and is so that you can write
2138 ACL clauses like: defer ratelimit = 15 / 1h
2141 arg the option string for ratelimit=
2142 where ACL_WHERE_xxxx indicating which ACL this is
2143 log_msgptr for error messages
2145 Returns: OK - Sender's rate is above limit
2146 FAIL - Sender's rate is below limit
2147 DEFER - Problem opening ratelimit database
2148 ERROR - Syntax error in options.
2152 acl_ratelimit(const uschar *arg, int where, uschar **log_msgptr)
2154 double limit, period, count;
2157 uschar *unique = NULL;
2159 BOOL leaky = FALSE, strict = FALSE, readonly = FALSE;
2160 BOOL noupdate = FALSE, badacl = FALSE;
2161 int mode = RATE_PER_WHAT;
2163 tree_node **anchor, *t;
2164 open_db dbblock, *dbm;
2166 dbdata_ratelimit *dbd;
2167 dbdata_ratelimit_unique *dbdb;
2170 /* Parse the first two options and record their values in expansion
2171 variables. These variables allow the configuration to have informative
2172 error messages based on rate limits obtained from a table lookup. */
2174 /* First is the maximum number of messages per period / maximum burst
2175 size, which must be greater than or equal to zero. Zero is useful for
2176 rate measurement as opposed to rate limiting. */
2178 sender_rate_limit = string_nextinlist(&arg, &sep, NULL, 0);
2179 if (sender_rate_limit == NULL)
2180 return ratelimit_error(log_msgptr, "sender rate limit not set");
2182 limit = Ustrtod(sender_rate_limit, &ss);
2183 if (tolower(*ss) == 'k') { limit *= 1024.0; ss++; }
2184 else if (tolower(*ss) == 'm') { limit *= 1024.0*1024.0; ss++; }
2185 else if (tolower(*ss) == 'g') { limit *= 1024.0*1024.0*1024.0; ss++; }
2187 if (limit < 0.0 || *ss != '\0')
2188 return ratelimit_error(log_msgptr,
2189 "\"%s\" is not a positive number", sender_rate_limit);
2191 /* Second is the rate measurement period / exponential smoothing time
2192 constant. This must be strictly greater than zero, because zero leads to
2193 run-time division errors. */
2195 sender_rate_period = string_nextinlist(&arg, &sep, NULL, 0);
2196 if (sender_rate_period == NULL) period = -1.0;
2197 else period = readconf_readtime(sender_rate_period, 0, FALSE);
2199 return ratelimit_error(log_msgptr,
2200 "\"%s\" is not a time value", sender_rate_period);
2202 /* By default we are counting one of something, but the per_rcpt,
2203 per_byte, and count options can change this. */
2207 /* Parse the other options. */
2209 while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size))
2212 if (strcmpic(ss, US"leaky") == 0) leaky = TRUE;
2213 else if (strcmpic(ss, US"strict") == 0) strict = TRUE;
2214 else if (strcmpic(ss, US"noupdate") == 0) noupdate = TRUE;
2215 else if (strcmpic(ss, US"readonly") == 0) readonly = TRUE;
2216 else if (strcmpic(ss, US"per_cmd") == 0) RATE_SET(mode, PER_CMD);
2217 else if (strcmpic(ss, US"per_conn") == 0)
2219 RATE_SET(mode, PER_CONN);
2220 if (where == ACL_WHERE_NOTSMTP || where == ACL_WHERE_NOTSMTP_START)
2223 else if (strcmpic(ss, US"per_mail") == 0)
2225 RATE_SET(mode, PER_MAIL);
2226 if (where > ACL_WHERE_NOTSMTP) badacl = TRUE;
2228 else if (strcmpic(ss, US"per_rcpt") == 0)
2230 /* If we are running in the RCPT ACL, then we'll count the recipients
2231 one by one, but if we are running when we have accumulated the whole
2232 list then we'll add them all in one batch. */
2233 if (where == ACL_WHERE_RCPT)
2234 RATE_SET(mode, PER_RCPT);
2235 else if (where >= ACL_WHERE_PREDATA && where <= ACL_WHERE_NOTSMTP)
2236 RATE_SET(mode, PER_ALLRCPTS), count = (double)recipients_count;
2237 else if (where == ACL_WHERE_MAIL || where > ACL_WHERE_NOTSMTP)
2238 RATE_SET(mode, PER_RCPT), badacl = TRUE;
2240 else if (strcmpic(ss, US"per_byte") == 0)
2242 /* If we have not yet received the message data and there was no SIZE
2243 declaration on the MAIL command, then it's safe to just use a value of
2244 zero and let the recorded rate decay as if nothing happened. */
2245 RATE_SET(mode, PER_MAIL);
2246 if (where > ACL_WHERE_NOTSMTP) badacl = TRUE;
2247 else count = message_size < 0 ? 0.0 : (double)message_size;
2249 else if (strcmpic(ss, US"per_addr") == 0)
2251 RATE_SET(mode, PER_RCPT);
2252 if (where != ACL_WHERE_RCPT) badacl = TRUE, unique = US"*";
2253 else unique = string_sprintf("%s@%s", deliver_localpart, deliver_domain);
2255 else if (strncmpic(ss, US"count=", 6) == 0)
2258 count = Ustrtod(ss+6, &e);
2259 if (count < 0.0 || *e != '\0')
2260 return ratelimit_error(log_msgptr,
2261 "\"%s\" is not a positive number", ss);
2263 else if (strncmpic(ss, US"unique=", 7) == 0)
2264 unique = string_copy(ss + 7);
2265 else if (key == NULL)
2266 key = string_copy(ss);
2268 key = string_sprintf("%s/%s", key, ss);
2271 /* Sanity check. When the badacl flag is set the update mode must either
2272 be readonly (which is the default if it is omitted) or, for backwards
2273 compatibility, a combination of noupdate and strict or leaky. */
2275 if (mode == RATE_PER_CLASH)
2276 return ratelimit_error(log_msgptr, "conflicting per_* options");
2277 if (leaky + strict + readonly > 1)
2278 return ratelimit_error(log_msgptr, "conflicting update modes");
2279 if (badacl && (leaky || strict) && !noupdate)
2280 return ratelimit_error(log_msgptr,
2281 "\"%s\" must not have /leaky or /strict option in %s ACL",
2282 ratelimit_option_string[mode], acl_wherenames[where]);
2284 /* Set the default values of any unset options. In readonly mode we
2285 perform the rate computation without any increment so that its value
2286 decays to eventually allow over-limit senders through. */
2288 if (noupdate) readonly = TRUE, leaky = strict = FALSE;
2289 if (badacl) readonly = TRUE;
2290 if (readonly) count = 0.0;
2291 if (!strict && !readonly) leaky = TRUE;
2292 if (mode == RATE_PER_WHAT) mode = RATE_PER_MAIL;
2294 /* Create the lookup key. If there is no explicit key, use sender_host_address.
2295 If there is no sender_host_address (e.g. -bs or acl_not_smtp) then we simply
2296 omit it. The smoothing constant (sender_rate_period) and the per_xxx options
2297 are added to the key because they alter the meaning of the stored data. */
2300 key = (sender_host_address == NULL)? US"" : sender_host_address;
2302 key = string_sprintf("%s/%s/%s%s",
2304 ratelimit_option_string[mode],
2305 unique == NULL ? "" : "unique/",
2309 debug_printf_indent("ratelimit condition count=%.0f %.1f/%s\n", count, limit, key);
2311 /* See if we have already computed the rate by looking in the relevant tree.
2312 For per-connection rate limiting, store tree nodes and dbdata in the permanent
2313 pool so that they survive across resets. In readonly mode we only remember the
2314 result for the rest of this command in case a later command changes it. After
2315 this bit of logic the code is independent of the per_* mode. */
2317 old_pool = store_pool;
2320 anchor = &ratelimiters_cmd;
2323 anchor = &ratelimiters_conn;
2324 store_pool = POOL_PERM;
2328 case RATE_PER_ALLRCPTS:
2329 anchor = &ratelimiters_mail;
2334 anchor = &ratelimiters_cmd;
2337 anchor = NULL; /* silence an "unused" complaint */
2338 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
2339 "internal ACL error: unknown ratelimit mode %d", mode);
2343 t = tree_search(*anchor, key);
2347 /* The following few lines duplicate some of the code below. */
2348 rc = (dbd->rate < limit)? FAIL : OK;
2349 store_pool = old_pool;
2350 sender_rate = string_sprintf("%.1f", dbd->rate);
2352 debug_printf_indent("ratelimit found pre-computed rate %s\n", sender_rate);
2356 /* We aren't using a pre-computed rate, so get a previously recorded rate
2357 from the database, which will be updated and written back if required. */
2359 dbm = dbfn_open(US"ratelimit", O_RDWR, &dbblock, TRUE);
2362 store_pool = old_pool;
2364 HDEBUG(D_acl) debug_printf_indent("ratelimit database not available\n");
2365 *log_msgptr = US"ratelimit database not available";
2368 dbdb = dbfn_read_with_length(dbm, key, &dbdb_size);
2371 gettimeofday(&tv, NULL);
2375 /* Locate the basic ratelimit block inside the DB data. */
2376 HDEBUG(D_acl) debug_printf_indent("ratelimit found key in database\n");
2379 /* Forget the old Bloom filter if it is too old, so that we count each
2380 repeating event once per period. We don't simply clear and re-use the old
2381 filter because we want its size to change if the limit changes. Note that
2382 we keep the dbd pointer for copying the rate into the new data block. */
2384 if(unique != NULL && tv.tv_sec > dbdb->bloom_epoch + period)
2386 HDEBUG(D_acl) debug_printf_indent("ratelimit discarding old Bloom filter\n");
2392 if(unique != NULL && dbdb_size < sizeof(*dbdb))
2394 HDEBUG(D_acl) debug_printf_indent("ratelimit discarding undersize Bloom filter\n");
2399 /* Allocate a new data block if the database lookup failed
2400 or the Bloom filter passed its age limit. */
2406 /* No Bloom filter. This basic ratelimit block is initialized below. */
2407 HDEBUG(D_acl) debug_printf_indent("ratelimit creating new rate data block\n");
2408 dbdb_size = sizeof(*dbd);
2409 dbdb = store_get(dbdb_size);
2414 HDEBUG(D_acl) debug_printf_indent("ratelimit creating new Bloom filter\n");
2416 /* See the long comment below for an explanation of the magic number 2.
2417 The filter has a minimum size in case the rate limit is very small;
2418 this is determined by the definition of dbdata_ratelimit_unique. */
2420 extra = (int)limit * 2 - sizeof(dbdb->bloom);
2421 if (extra < 0) extra = 0;
2422 dbdb_size = sizeof(*dbdb) + extra;
2423 dbdb = store_get(dbdb_size);
2424 dbdb->bloom_epoch = tv.tv_sec;
2425 dbdb->bloom_size = sizeof(dbdb->bloom) + extra;
2426 memset(dbdb->bloom, 0, dbdb->bloom_size);
2428 /* Preserve any basic ratelimit data (which is our longer-term memory)
2429 by copying it from the discarded block. */
2439 /* If we are counting unique events, find out if this event is new or not.
2440 If the client repeats the event during the current period then it should be
2441 counted. We skip this code in readonly mode for efficiency, because any
2442 changes to the filter will be discarded and because count is already set to
2445 if (unique != NULL && !readonly)
2447 /* We identify unique events using a Bloom filter. (You can find my
2448 notes on Bloom filters at http://fanf.livejournal.com/81696.html)
2449 With the per_addr option, an "event" is a recipient address, though the
2450 user can use the unique option to define their own events. We only count
2451 an event if we have not seen it before.
2453 We size the filter according to the rate limit, which (in leaky mode)
2454 is the limit on the population of the filter. We allow 16 bits of space
2455 per entry (see the construction code above) and we set (up to) 8 of them
2456 when inserting an element (see the loop below). The probability of a false
2457 positive (an event we have not seen before but which we fail to count) is
2461 allzero = exp(-numhash * pop / size)
2462 = exp(-0.5 * pop / limit)
2463 fpr = pow(1 - allzero, numhash)
2465 For senders at the limit the fpr is 0.06% or 1 in 1700
2466 and for senders at half the limit it is 0.0006% or 1 in 170000
2468 In strict mode the Bloom filter can fill up beyond the normal limit, in
2469 which case the false positive rate will rise. This means that the
2470 measured rate for very fast senders can bogusly drop off after a while.
2472 At twice the limit, the fpr is 2.5% or 1 in 40
2473 At four times the limit, it is 31% or 1 in 3.2
2475 It takes ln(pop/limit) periods for an over-limit burst of pop events to
2476 decay below the limit, and if this is more than one then the Bloom filter
2477 will be discarded before the decay gets that far. The false positive rate
2478 at this threshold is 9.3% or 1 in 10.7. */
2481 unsigned n, hash, hinc;
2485 /* Instead of using eight independent hash values, we combine two values
2486 using the formula h1 + n * h2. This does not harm the Bloom filter's
2487 performance, and means the amount of hash we need is independent of the
2488 number of bits we set in the filter. */
2490 md5_start(&md5info);
2491 md5_end(&md5info, unique, Ustrlen(unique), md5sum);
2492 hash = md5sum[0] | md5sum[1] << 8 | md5sum[2] << 16 | md5sum[3] << 24;
2493 hinc = md5sum[4] | md5sum[5] << 8 | md5sum[6] << 16 | md5sum[7] << 24;
2495 /* Scan the bits corresponding to this event. A zero bit means we have
2496 not seen it before. Ensure all bits are set to record this event. */
2498 HDEBUG(D_acl) debug_printf_indent("ratelimit checking uniqueness of %s\n", unique);
2501 for (n = 0; n < 8; n++, hash += hinc)
2503 int bit = 1 << (hash % 8);
2504 int byte = (hash / 8) % dbdb->bloom_size;
2505 if ((dbdb->bloom[byte] & bit) == 0)
2507 dbdb->bloom[byte] |= bit;
2512 /* If this event has occurred before, do not count it. */
2516 HDEBUG(D_acl) debug_printf_indent("ratelimit event found in Bloom filter\n");
2520 HDEBUG(D_acl) debug_printf_indent("ratelimit event added to Bloom filter\n");
2523 /* If there was no previous ratelimit data block for this key, initialize
2524 the new one, otherwise update the block from the database. The initial rate
2525 is what would be computed by the code below for an infinite interval. */
2529 HDEBUG(D_acl) debug_printf_indent("ratelimit initializing new key's rate data\n");
2531 dbd->time_stamp = tv.tv_sec;
2532 dbd->time_usec = tv.tv_usec;
2537 /* The smoothed rate is computed using an exponentially weighted moving
2538 average adjusted for variable sampling intervals. The standard EWMA for
2539 a fixed sampling interval is: f'(t) = (1 - a) * f(t) + a * f'(t - 1)
2540 where f() is the measured value and f'() is the smoothed value.
2542 Old data decays out of the smoothed value exponentially, such that data n
2543 samples old is multiplied by a^n. The exponential decay time constant p
2544 is defined such that data p samples old is multiplied by 1/e, which means
2545 that a = exp(-1/p). We can maintain the same time constant for a variable
2546 sampling interval i by using a = exp(-i/p).
2548 The rate we are measuring is messages per period, suitable for directly
2549 comparing with the limit. The average rate between now and the previous
2550 message is period / interval, which we feed into the EWMA as the sample.
2552 It turns out that the number of messages required for the smoothed rate
2553 to reach the limit when they are sent in a burst is equal to the limit.
2554 This can be seen by analysing the value of the smoothed rate after N
2555 messages sent at even intervals. Let k = (1 - a) * p/i
2557 rate_1 = (1 - a) * p/i + a * rate_0
2559 rate_2 = k + a * rate_1
2560 = k + a * k + a^2 * rate_0
2561 rate_3 = k + a * k + a^2 * k + a^3 * rate_0
2562 rate_N = rate_0 * a^N + k * SUM(x=0..N-1)(a^x)
2563 = rate_0 * a^N + k * (1 - a^N) / (1 - a)
2564 = rate_0 * a^N + p/i * (1 - a^N)
2566 When N is large, a^N -> 0 so rate_N -> p/i as desired.
2568 rate_N = p/i + (rate_0 - p/i) * a^N
2569 a^N = (rate_N - p/i) / (rate_0 - p/i)
2570 N * -i/p = log((rate_N - p/i) / (rate_0 - p/i))
2571 N = p/i * log((rate_0 - p/i) / (rate_N - p/i))
2573 Numerical analysis of the above equation, setting the computed rate to
2574 increase from rate_0 = 0 to rate_N = limit, shows that for large sending
2575 rates, p/i, the number of messages N = limit. So limit serves as both the
2576 maximum rate measured in messages per period, and the maximum number of
2577 messages that can be sent in a fast burst. */
2579 double this_time = (double)tv.tv_sec
2580 + (double)tv.tv_usec / 1000000.0;
2581 double prev_time = (double)dbd->time_stamp
2582 + (double)dbd->time_usec / 1000000.0;
2584 /* We must avoid division by zero, and deal gracefully with the clock going
2585 backwards. If we blunder ahead when time is in reverse then the computed
2586 rate will be bogus. To be safe we clamp interval to a very small number. */
2588 double interval = this_time - prev_time <= 0.0 ? 1e-9
2589 : this_time - prev_time;
2591 double i_over_p = interval / period;
2592 double a = exp(-i_over_p);
2594 /* Combine the instantaneous rate (period / interval) with the previous rate
2595 using the smoothing factor a. In order to measure sized events, multiply the
2596 instantaneous rate by the count of bytes or recipients etc. */
2598 dbd->time_stamp = tv.tv_sec;
2599 dbd->time_usec = tv.tv_usec;
2600 dbd->rate = (1 - a) * count / i_over_p + a * dbd->rate;
2602 /* When events are very widely spaced the computed rate tends towards zero.
2603 Although this is accurate it turns out not to be useful for our purposes,
2604 especially when the first event after a long silence is the start of a spam
2605 run. A more useful model is that the rate for an isolated event should be the
2606 size of the event per the period size, ignoring the lack of events outside
2607 the current period and regardless of where the event falls in the period. So,
2608 if the interval was so long that the calculated rate is unhelpfully small, we
2609 re-initialize the rate. In the absence of higher-rate bursts, the condition
2610 below is true if the interval is greater than the period. */
2612 if (dbd->rate < count) dbd->rate = count;
2615 /* Clients sending at the limit are considered to be over the limit.
2616 This matters for edge cases such as a limit of zero, when the client
2617 should be completely blocked. */
2619 rc = (dbd->rate < limit)? FAIL : OK;
2621 /* Update the state if the rate is low or if we are being strict. If we
2622 are in leaky mode and the sender's rate is too high, we do not update
2623 the recorded rate in order to avoid an over-aggressive sender's retry
2624 rate preventing them from getting any email through. If readonly is set,
2625 neither leaky nor strict are set, so we do not do any updates. */
2627 if ((rc == FAIL && leaky) || strict)
2629 dbfn_write(dbm, key, dbdb, dbdb_size);
2630 HDEBUG(D_acl) debug_printf_indent("ratelimit db updated\n");
2634 HDEBUG(D_acl) debug_printf_indent("ratelimit db not updated: %s\n",
2635 readonly? "readonly mode" : "over the limit, but leaky");
2640 /* Store the result in the tree for future reference. */
2642 t = store_get(sizeof(tree_node) + Ustrlen(key));
2644 Ustrcpy(t->name, key);
2645 (void)tree_insertnode(anchor, t);
2647 /* We create the formatted version of the sender's rate very late in
2648 order to ensure that it is done using the correct storage pool. */
2650 store_pool = old_pool;
2651 sender_rate = string_sprintf("%.1f", dbd->rate);
2654 debug_printf_indent("ratelimit computed rate %s\n", sender_rate);
2661 /*************************************************
2662 * The udpsend ACL modifier *
2663 *************************************************/
2665 /* Called by acl_check_condition() below.
2668 arg the option string for udpsend=
2669 log_msgptr for error messages
2671 Returns: OK - Completed.
2672 DEFER - Problem with DNS lookup.
2673 ERROR - Syntax error in options.
2677 acl_udpsend(const uschar *arg, uschar **log_msgptr)
2689 hostname = string_nextinlist(&arg, &sep, NULL, 0);
2690 portstr = string_nextinlist(&arg, &sep, NULL, 0);
2694 *log_msgptr = US"missing destination host in \"udpsend\" modifier";
2699 *log_msgptr = US"missing destination port in \"udpsend\" modifier";
2704 *log_msgptr = US"missing datagram payload in \"udpsend\" modifier";
2707 portnum = Ustrtol(portstr, &portend, 10);
2708 if (*portend != '\0')
2710 *log_msgptr = US"bad destination port in \"udpsend\" modifier";
2714 /* Make a single-item host list. */
2715 h = store_get(sizeof(host_item));
2716 memset(h, 0, sizeof(host_item));
2721 if (string_is_ip_address(hostname, NULL))
2722 h->address = hostname, r = HOST_FOUND;
2724 r = host_find_byname(h, NULL, 0, NULL, FALSE);
2725 if (r == HOST_FIND_FAILED || r == HOST_FIND_AGAIN)
2727 *log_msgptr = US"DNS lookup failed in \"udpsend\" modifier";
2732 debug_printf_indent("udpsend [%s]:%d %s\n", h->address, portnum, arg);
2734 r = s = ip_connectedsocket(SOCK_DGRAM, h->address, portnum, portnum,
2736 if (r < 0) goto defer;
2738 r = send(s, arg, len, 0);
2741 errstr = US strerror(errno);
2749 string_sprintf("\"udpsend\" truncated from %d to %d octets", len, r);
2754 debug_printf_indent("udpsend %d bytes\n", r);
2759 *log_msgptr = string_sprintf("\"udpsend\" failed: %s", errstr);
2765 /*************************************************
2766 * Handle conditions/modifiers on an ACL item *
2767 *************************************************/
2769 /* Called from acl_check() below.
2773 cb ACL condition block - if NULL, result is OK
2774 where where called from
2775 addr the address being checked for RCPT, or NULL
2776 level the nesting level
2777 epp pointer to pass back TRUE if "endpass" encountered
2778 (applies only to "accept" and "discard")
2779 user_msgptr user message pointer
2780 log_msgptr log message pointer
2781 basic_errno pointer to where to put verify error
2783 Returns: OK - all conditions are met
2784 DISCARD - an "acl" condition returned DISCARD - only allowed
2785 for "accept" or "discard" verbs
2786 FAIL - at least one condition fails
2787 FAIL_DROP - an "acl" condition returned FAIL_DROP
2788 DEFER - can't tell at the moment (typically, lookup defer,
2789 but can be temporary callout problem)
2790 ERROR - ERROR from nested ACL or expansion failure or other
2795 acl_check_condition(int verb, acl_condition_block *cb, int where,
2796 address_item *addr, int level, BOOL *epp, uschar **user_msgptr,
2797 uschar **log_msgptr, int *basic_errno)
2799 uschar *user_message = NULL;
2800 uschar *log_message = NULL;
2802 #ifdef WITH_CONTENT_SCAN
2806 for (; cb != NULL; cb = cb->next)
2811 /* The message and log_message items set up messages to be used in
2812 case of rejection. They are expanded later. */
2814 if (cb->type == ACLC_MESSAGE)
2816 HDEBUG(D_acl) debug_printf_indent(" message: %s\n", cb->arg);
2817 user_message = cb->arg;
2821 if (cb->type == ACLC_LOG_MESSAGE)
2823 HDEBUG(D_acl) debug_printf_indent("l_message: %s\n", cb->arg);
2824 log_message = cb->arg;
2828 /* The endpass "condition" just sets a flag to show it occurred. This is
2829 checked at compile time to be on an "accept" or "discard" item. */
2831 if (cb->type == ACLC_ENDPASS)
2837 /* For other conditions and modifiers, the argument is expanded now for some
2838 of them, but not for all, because expansion happens down in some lower level
2839 checking functions in some cases. */
2841 if (!conditions[cb->type].expand_at_top)
2843 else if (!(arg = expand_string(cb->arg)))
2845 if (expand_string_forcedfail) continue;
2846 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s",
2847 cb->arg, expand_string_message);
2848 return search_find_defer ? DEFER : ERROR;
2851 /* Show condition, and expanded condition if it's different */
2856 debug_printf_indent("check %s%s %n",
2857 (!conditions[cb->type].is_modifier && cb->u.negated)? "!":"",
2858 conditions[cb->type].name, &lhswidth);
2860 if (cb->type == ACLC_SET)
2862 debug_printf("acl_%s ", cb->u.varname);
2863 lhswidth += 5 + Ustrlen(cb->u.varname);
2866 debug_printf("= %s\n", cb->arg);
2869 debug_printf("%.*s= %s\n", lhswidth,
2873 /* Check that this condition makes sense at this time */
2875 if ((conditions[cb->type].forbids & (1 << where)) != 0)
2877 *log_msgptr = string_sprintf("cannot %s %s condition in %s ACL",
2878 conditions[cb->type].is_modifier ? "use" : "test",
2879 conditions[cb->type].name, acl_wherenames[where]);
2883 /* Run the appropriate test for each condition, or take the appropriate
2884 action for the remaining modifiers. */
2888 case ACLC_ADD_HEADER:
2892 /* A nested ACL that returns "discard" makes sense only for an "accept" or
2896 rc = acl_check_wargs(where, addr, arg, user_msgptr, log_msgptr);
2897 if (rc == DISCARD && verb != ACL_ACCEPT && verb != ACL_DISCARD)
2899 *log_msgptr = string_sprintf("nested ACL returned \"discard\" for "
2900 "\"%s\" command (only allowed with \"accept\" or \"discard\")",
2906 case ACLC_AUTHENTICATED:
2907 rc = (sender_host_authenticated == NULL)? FAIL :
2908 match_isinlist(sender_host_authenticated, &arg, 0, NULL, NULL, MCL_STRING,
2912 #ifdef EXPERIMENTAL_BRIGHTMAIL
2913 case ACLC_BMI_OPTIN:
2915 int old_pool = store_pool;
2916 store_pool = POOL_PERM;
2917 bmi_current_optin = string_copy(arg);
2918 store_pool = old_pool;
2923 case ACLC_CONDITION:
2924 /* The true/false parsing here should be kept in sync with that used in
2925 expand.c when dealing with ECOND_BOOL so that we don't have too many
2926 different definitions of what can be a boolean. */
2928 ? Ustrspn(arg+1, "0123456789") == Ustrlen(arg+1) /* Negative number */
2929 : Ustrspn(arg, "0123456789") == Ustrlen(arg)) /* Digits, or empty */
2930 rc = (Uatoi(arg) == 0)? FAIL : OK;
2932 rc = (strcmpic(arg, US"no") == 0 ||
2933 strcmpic(arg, US"false") == 0)? FAIL :
2934 (strcmpic(arg, US"yes") == 0 ||
2935 strcmpic(arg, US"true") == 0)? OK : DEFER;
2937 *log_msgptr = string_sprintf("invalid \"condition\" value \"%s\"", arg);
2940 case ACLC_CONTINUE: /* Always succeeds */
2945 const uschar *p = NULL;
2946 control_type = decode_control(arg, &p, where, log_msgptr);
2948 /* Check if this control makes sense at this time */
2950 if (controls_list[control_type].forbids & (1 << where))
2952 *log_msgptr = string_sprintf("cannot use \"control=%s\" in %s ACL",
2953 controls_list[control_type].name, acl_wherenames[where]);
2957 switch(control_type)
2959 case CONTROL_AUTH_UNADVERTISED:
2960 allow_auth_unadvertised = TRUE;
2963 #ifdef EXPERIMENTAL_BRIGHTMAIL
2964 case CONTROL_BMI_RUN:
2969 #ifndef DISABLE_DKIM
2970 case CONTROL_DKIM_VERIFY:
2971 dkim_disable_verify = TRUE;
2972 #ifdef EXPERIMENTAL_DMARC
2973 /* Since DKIM was blocked, skip DMARC too */
2974 dmarc_disable_verify = TRUE;
2975 dmarc_enable_forensic = FALSE;
2980 #ifdef EXPERIMENTAL_DMARC
2981 case CONTROL_DMARC_VERIFY:
2982 dmarc_disable_verify = TRUE;
2985 case CONTROL_DMARC_FORENSIC:
2986 dmarc_enable_forensic = TRUE;
2993 int fd, af, level, optname, value;
2994 /* If we are acting on stdin, the setsockopt may fail if stdin is not
2995 a socket; we can accept that, we'll just debug-log failures anyway. */
2996 fd = fileno(smtp_in);
2997 af = ip_get_address_family(fd);
3001 debug_printf_indent("smtp input is probably not a socket [%s], not setting DSCP\n",
3005 if (dscp_lookup(p+1, af, &level, &optname, &value))
3007 if (setsockopt(fd, level, optname, &value, sizeof(value)) < 0)
3009 HDEBUG(D_acl) debug_printf_indent("failed to set input DSCP[%s]: %s\n",
3010 p+1, strerror(errno));
3014 HDEBUG(D_acl) debug_printf_indent("set input DSCP to \"%s\"\n", p+1);
3019 *log_msgptr = string_sprintf("unrecognised DSCP value in \"control=%s\"", arg);
3025 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3033 case CONTROL_CASEFUL_LOCAL_PART:
3034 deliver_localpart = addr->cc_local_part;
3037 case CONTROL_CASELOWER_LOCAL_PART:
3038 deliver_localpart = addr->lc_local_part;
3041 case CONTROL_ENFORCE_SYNC:
3042 smtp_enforce_sync = TRUE;
3045 case CONTROL_NO_ENFORCE_SYNC:
3046 smtp_enforce_sync = FALSE;
3049 #ifdef WITH_CONTENT_SCAN
3050 case CONTROL_NO_MBOX_UNSPOOL:
3051 no_mbox_unspool = TRUE;
3055 case CONTROL_NO_MULTILINE:
3056 no_multiline_responses = TRUE;
3059 case CONTROL_NO_PIPELINING:
3060 pipelining_enable = FALSE;
3063 case CONTROL_NO_DELAY_FLUSH:
3064 disable_delay_flush = TRUE;
3067 case CONTROL_NO_CALLOUT_FLUSH:
3068 disable_callout_flush = TRUE;
3071 case CONTROL_FAKEREJECT:
3072 cancel_cutthrough_connection("fakereject");
3073 case CONTROL_FAKEDEFER:
3074 fake_response = (control_type == CONTROL_FAKEDEFER) ? DEFER : FAIL;
3077 const uschar *pp = p + 1;
3078 while (*pp != 0) pp++;
3079 fake_response_text = expand_string(string_copyn(p+1, pp-p-1));
3084 /* Explicitly reset to default string */
3085 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).";
3089 case CONTROL_FREEZE:
3090 deliver_freeze = TRUE;
3091 deliver_frozen_at = time(NULL);
3092 freeze_tell = freeze_tell_config; /* Reset to configured value */
3093 if (Ustrncmp(p, "/no_tell", 8) == 0)
3100 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3103 cancel_cutthrough_connection("item frozen");
3106 case CONTROL_QUEUE_ONLY:
3107 queue_only_policy = TRUE;
3108 cancel_cutthrough_connection("queueing forced");
3111 case CONTROL_SUBMISSION:
3112 originator_name = US"";
3113 submission_mode = TRUE;
3116 if (Ustrncmp(p, "/sender_retain", 14) == 0)
3119 active_local_sender_retain = TRUE;
3120 active_local_from_check = FALSE;
3122 else if (Ustrncmp(p, "/domain=", 8) == 0)
3124 const uschar *pp = p + 8;
3125 while (*pp != 0 && *pp != '/') pp++;
3126 submission_domain = string_copyn(p+8, pp-p-8);
3129 /* The name= option must be last, because it swallows the rest of
3131 else if (Ustrncmp(p, "/name=", 6) == 0)
3133 const uschar *pp = p + 6;
3134 while (*pp != 0) pp++;
3135 submission_name = string_copy(parse_fix_phrase(p+6, pp-p-6,
3136 big_buffer, big_buffer_size));
3143 *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
3150 uschar * debug_tag = NULL;
3151 uschar * debug_opts = NULL;
3156 const uschar * pp = p+1;
3157 if (Ustrncmp(pp, "tag=", 4) == 0)
3159 for (pp += 4; *pp && *pp != '/';) pp++;
3160 debug_tag = string_copyn(p+5, pp-p-5);
3162 else if (Ustrncmp(pp, "opts=", 5) == 0)
3164 for (pp += 5; *pp && *pp != '/';) pp++;
3165 debug_opts = string_copyn(p+6, pp-p-6);
3167 else if (Ustrncmp(pp, "kill", 4) == 0)
3169 for (pp += 4; *pp && *pp != '/';) pp++;
3173 while (*pp && *pp != '/') pp++;
3178 debug_logging_stop();
3180 debug_logging_activate(debug_tag, debug_opts);
3184 case CONTROL_SUPPRESS_LOCAL_FIXUPS:
3185 suppress_local_fixups = TRUE;
3188 case CONTROL_CUTTHROUGH_DELIVERY:
3189 #ifndef DISABLE_PRDR
3194 /* Too hard to think about for now. We might in future cutthrough
3195 the case where both sides handle prdr and this-node prdr acl
3197 *log_msgptr = string_sprintf("PRDR on %s reception\n", arg);
3201 *log_msgptr = US"frozen";
3202 else if (queue_only_policy)
3203 *log_msgptr = US"queue-only";
3204 else if (fake_response == FAIL)
3205 *log_msgptr = US"fakereject";
3208 if (rcpt_count == 1)
3210 cutthrough.delivery = TRUE;
3213 const uschar * pp = p+1;
3214 if (Ustrncmp(pp, "defer=", 6) == 0)
3217 if (Ustrncmp(pp, "pass", 4) == 0) cutthrough.defer_pass = TRUE;
3218 /* else if (Ustrncmp(pp, "spool") == 0) ; default */
3221 while (*pp && *pp != '/') pp++;
3227 *log_msgptr = string_sprintf("\"control=%s\" on %s item",
3233 case CONTROL_UTF8_DOWNCONVERT:
3238 message_utf8_downconvert = 1;
3239 addr->prop.utf8_downcvt = TRUE;
3240 addr->prop.utf8_downcvt_maybe = FALSE;
3246 message_utf8_downconvert = 0;
3247 addr->prop.utf8_downcvt = FALSE;
3248 addr->prop.utf8_downcvt_maybe = FALSE;
3252 if (p[1] == '-' && p[2] == '1')
3254 message_utf8_downconvert = -1;
3255 addr->prop.utf8_downcvt = FALSE;
3256 addr->prop.utf8_downcvt_maybe = TRUE;
3260 *log_msgptr = US"bad option value for control=utf8_downconvert";
3264 message_utf8_downconvert = 1;
3265 addr->prop.utf8_downcvt = TRUE;
3266 addr->prop.utf8_downcvt_maybe = FALSE;
3276 #ifdef EXPERIMENTAL_DCC
3279 /* Separate the regular expression and any optional parameters. */
3280 const uschar * list = arg;
3281 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
3282 /* Run the dcc backend. */
3283 rc = dcc_process(&ss);
3284 /* Modify return code based upon the existence of options. */
3285 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size)))
3286 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
3287 rc = FAIL; /* FAIL so that the message is passed to the next ACL */
3292 #ifdef WITH_CONTENT_SCAN
3294 rc = mime_decode(&arg);
3300 int delay = readconf_readtime(arg, 0, FALSE);
3303 *log_msgptr = string_sprintf("syntax error in argument for \"delay\" "
3304 "modifier: \"%s\" is not a time value", arg);
3309 HDEBUG(D_acl) debug_printf_indent("delay modifier requests %d-second delay\n",
3314 debug_printf_indent("delay skipped in -bh checking mode\n");
3317 /* NOTE 1: Remember that we may be
3318 dealing with stdin/stdout here, in addition to TCP/IP connections.
3319 Also, delays may be specified for non-SMTP input, where smtp_out and
3320 smtp_in will be NULL. Whatever is done must work in all cases.
3322 NOTE 2: The added feature of flushing the output before a delay must
3323 apply only to SMTP input. Hence the test for smtp_out being non-NULL.
3328 if (smtp_out != NULL && !disable_delay_flush)
3331 #if !defined(NO_POLL_H) && defined (POLLRDHUP)
3337 p.fd = fileno(smtp_out);
3338 p.events = POLLRDHUP;
3341 if (poll(&p, n, delay*1000) > 0)
3342 HDEBUG(D_acl) debug_printf_indent("delay cancelled by peer close\n");
3345 /* It appears to be impossible to detect that a TCP/IP connection has
3346 gone away without reading from it. This means that we cannot shorten
3347 the delay below if the client goes away, because we cannot discover
3348 that the client has closed its end of the connection. (The connection
3349 is actually in a half-closed state, waiting for the server to close its
3350 end.) It would be nice to be able to detect this state, so that the
3351 Exim process is not held up unnecessarily. However, it seems that we
3352 can't. The poll() function does not do the right thing, and in any case
3353 it is not always available.
3356 while (delay > 0) delay = sleep(delay);
3363 #ifndef DISABLE_DKIM
3364 case ACLC_DKIM_SIGNER:
3365 if (dkim_cur_signer != NULL)
3366 rc = match_isinlist(dkim_cur_signer,
3367 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
3372 case ACLC_DKIM_STATUS:
3373 rc = match_isinlist(dkim_exim_expand_query(DKIM_VERIFY_STATUS),
3374 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
3378 #ifdef EXPERIMENTAL_DMARC
3379 case ACLC_DMARC_STATUS:
3380 if (!dmarc_has_been_checked)
3382 dmarc_has_been_checked = TRUE;
3383 /* used long way of dmarc_exim_expand_query() in case we need more
3384 * view into the process in the future. */
3385 rc = match_isinlist(dmarc_exim_expand_query(DMARC_VERIFY_STATUS),
3386 &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL);
3391 rc = verify_check_dnsbl(where, &arg, log_msgptr);
3395 rc = match_isinlist(addr->domain, &arg, 0, &domainlist_anchor,
3396 addr->domain_cache, MCL_DOMAIN, TRUE, CUSS &deliver_domain_data);
3399 /* The value in tls_cipher is the full cipher name, for example,
3400 TLSv1:DES-CBC3-SHA:168, whereas the values to test for are just the
3401 cipher names such as DES-CBC3-SHA. But program defensively. We don't know
3402 what may in practice come out of the SSL library - which at the time of
3403 writing is poorly documented. */
3405 case ACLC_ENCRYPTED:
3406 if (tls_in.cipher == NULL) rc = FAIL; else
3408 uschar *endcipher = NULL;
3409 uschar *cipher = Ustrchr(tls_in.cipher, ':');
3410 if (cipher == NULL) cipher = tls_in.cipher; else
3412 endcipher = Ustrchr(++cipher, ':');
3413 if (endcipher != NULL) *endcipher = 0;
3415 rc = match_isinlist(cipher, &arg, 0, NULL, NULL, MCL_STRING, TRUE, NULL);
3416 if (endcipher != NULL) *endcipher = ':';
3420 /* Use verify_check_this_host() instead of verify_check_host() so that
3421 we can pass over &host_data to catch any looked up data. Once it has been
3422 set, it retains its value so that it's still there if another ACL verb
3423 comes through here and uses the cache. However, we must put it into
3424 permanent store in case it is also expected to be used in a subsequent
3425 message in the same SMTP connection. */
3428 rc = verify_check_this_host(&arg, sender_host_cache, NULL,
3429 (sender_host_address == NULL)? US"" : sender_host_address,
3431 if (rc == DEFER) *log_msgptr = search_error_message;
3432 if (host_data) host_data = string_copy_malloc(host_data);
3435 case ACLC_LOCAL_PARTS:
3436 rc = match_isinlist(addr->cc_local_part, &arg, 0,
3437 &localpartlist_anchor, addr->localpart_cache, MCL_LOCALPART, TRUE,
3438 CUSS &deliver_localpart_data);
3441 case ACLC_LOG_REJECT_TARGET:
3445 const uschar *s = arg;
3447 while ((ss = string_nextinlist(&s, &sep, big_buffer, big_buffer_size)))
3449 if (Ustrcmp(ss, "main") == 0) logbits |= LOG_MAIN;
3450 else if (Ustrcmp(ss, "panic") == 0) logbits |= LOG_PANIC;
3451 else if (Ustrcmp(ss, "reject") == 0) logbits |= LOG_REJECT;
3454 logbits |= LOG_MAIN|LOG_REJECT;
3455 log_write(0, LOG_MAIN|LOG_PANIC, "unknown log name \"%s\" in "
3456 "\"log_reject_target\" in %s ACL", ss, acl_wherenames[where]);
3459 log_reject_target = logbits;
3466 const uschar *s = arg;
3472 if (Ustrncmp(s, "main", 4) == 0)
3473 { logbits |= LOG_MAIN; s += 4; }
3474 else if (Ustrncmp(s, "panic", 5) == 0)
3475 { logbits |= LOG_PANIC; s += 5; }
3476 else if (Ustrncmp(s, "reject", 6) == 0)
3477 { logbits |= LOG_REJECT; s += 6; }
3480 logbits = LOG_MAIN|LOG_PANIC;
3481 s = string_sprintf(":unknown log name in \"%s\" in "
3482 "\"logwrite\" in %s ACL", arg, acl_wherenames[where]);
3488 while (isspace(*s)) s++;
3491 if (logbits == 0) logbits = LOG_MAIN;
3492 log_write(0, logbits, "%s", string_printing(s));
3496 #ifdef WITH_CONTENT_SCAN
3497 case ACLC_MALWARE: /* Run the malware backend. */
3499 /* Separate the regular expression and any optional parameters. */
3500 const uschar * list = arg;
3501 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
3503 BOOL defer_ok = FALSE;
3506 while ((opt = string_nextinlist(&list, &sep, NULL, 0)))
3507 if (strcmpic(opt, US"defer_ok") == 0)
3509 else if ( strncmpic(opt, US"tmo=", 4) == 0
3510 && (timeout = readconf_readtime(opt+4, '\0', FALSE)) < 0
3513 *log_msgptr = string_sprintf("bad timeout value in '%s'", opt);
3517 rc = malware(ss, timeout);
3518 if (rc == DEFER && defer_ok)
3519 rc = FAIL; /* FAIL so that the message is passed to the next ACL */
3523 case ACLC_MIME_REGEX:
3524 rc = mime_regex(&arg);
3529 queue_name = string_copy_malloc(arg);
3532 case ACLC_RATELIMIT:
3533 rc = acl_ratelimit(arg, where, log_msgptr);
3536 case ACLC_RECIPIENTS:
3537 rc = match_address_list((const uschar *)addr->address, TRUE, TRUE, &arg, NULL, -1, 0,
3538 CUSS &recipient_data);
3541 #ifdef WITH_CONTENT_SCAN
3547 case ACLC_REMOVE_HEADER:
3548 setup_remove_header(arg);
3551 case ACLC_SENDER_DOMAINS:
3554 sdomain = Ustrrchr(sender_address, '@');
3555 sdomain = (sdomain == NULL)? US"" : sdomain + 1;
3556 rc = match_isinlist(sdomain, &arg, 0, &domainlist_anchor,
3557 sender_domain_cache, MCL_DOMAIN, TRUE, NULL);
3562 rc = match_address_list((const uschar *)sender_address, TRUE, TRUE, &arg,
3563 sender_address_cache, -1, 0, CUSS &sender_data);
3566 /* Connection variables must persist forever */
3570 int old_pool = store_pool;
3571 if ( cb->u.varname[0] == 'c'
3572 #ifndef DISABLE_EVENT
3573 || event_name /* An event is being delivered */
3576 store_pool = POOL_PERM;
3577 acl_var_create(cb->u.varname)->data.ptr = string_copy(arg);
3578 store_pool = old_pool;
3582 #ifdef WITH_CONTENT_SCAN
3585 /* Separate the regular expression and any optional parameters. */
3586 const uschar * list = arg;
3587 uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size);
3588 /* Run the spam backend. */
3589 rc = spam(CUSS &ss);
3590 /* Modify return code based upon the existence of options. */
3591 while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size))
3593 if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
3595 /* FAIL so that the message is passed to the next ACL */
3603 #ifdef EXPERIMENTAL_SPF
3605 rc = spf_process(&arg, sender_address, SPF_PROCESS_NORMAL);
3607 case ACLC_SPF_GUESS:
3608 rc = spf_process(&arg, sender_address, SPF_PROCESS_GUESS);
3613 rc = acl_udpsend(arg, log_msgptr);
3616 /* If the verb is WARN, discard any user message from verification, because
3617 such messages are SMTP responses, not header additions. The latter come
3618 only from explicit "message" modifiers. However, put the user message into
3619 $acl_verify_message so it can be used in subsequent conditions or modifiers
3620 (until something changes it). */
3623 rc = acl_verify(where, addr, arg, user_msgptr, log_msgptr, basic_errno);
3625 acl_verify_message = *user_msgptr;
3626 if (verb == ACL_WARN) *user_msgptr = NULL;
3630 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown "
3631 "condition %d", cb->type);
3635 /* If a condition was negated, invert OK/FAIL. */
3637 if (!conditions[cb->type].is_modifier && cb->u.negated)
3638 if (rc == OK) rc = FAIL;
3639 else if (rc == FAIL || rc == FAIL_DROP) rc = OK;
3641 if (rc != OK) break; /* Conditions loop */
3645 /* If the result is the one for which "message" and/or "log_message" are used,
3646 handle the values of these modifiers. If there isn't a log message set, we make
3647 it the same as the user message.
3649 "message" is a user message that will be included in an SMTP response. Unless
3650 it is empty, it overrides any previously set user message.
3652 "log_message" is a non-user message, and it adds to any existing non-user
3653 message that is already set.
3655 Most verbs have but a single return for which the messages are relevant, but
3656 for "discard", it's useful to have the log message both when it succeeds and
3657 when it fails. For "accept", the message is used in the OK case if there is no
3658 "endpass", but (for backwards compatibility) in the FAIL case if "endpass" is
3661 if (*epp && rc == OK) user_message = NULL;
3663 if (((1<<rc) & msgcond[verb]) != 0)
3666 uschar *old_user_msgptr = *user_msgptr;
3667 uschar *old_log_msgptr = (*log_msgptr != NULL)? *log_msgptr : old_user_msgptr;
3669 /* If the verb is "warn", messages generated by conditions (verification or
3670 nested ACLs) are always discarded. This also happens for acceptance verbs
3671 when they actually do accept. Only messages specified at this level are used.
3672 However, the value of an existing message is available in $acl_verify_message
3673 during expansions. */
3675 if (verb == ACL_WARN ||
3676 (rc == OK && (verb == ACL_ACCEPT || verb == ACL_DISCARD)))
3677 *log_msgptr = *user_msgptr = NULL;
3679 if (user_message != NULL)
3681 acl_verify_message = old_user_msgptr;
3682 expmessage = expand_string(user_message);
3683 if (expmessage == NULL)
3685 if (!expand_string_forcedfail)
3686 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
3687 user_message, expand_string_message);
3689 else if (expmessage[0] != 0) *user_msgptr = expmessage;
3692 if (log_message != NULL)
3694 acl_verify_message = old_log_msgptr;
3695 expmessage = expand_string(log_message);
3696 if (expmessage == NULL)
3698 if (!expand_string_forcedfail)
3699 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
3700 log_message, expand_string_message);
3702 else if (expmessage[0] != 0)
3704 *log_msgptr = (*log_msgptr == NULL)? expmessage :
3705 string_sprintf("%s: %s", expmessage, *log_msgptr);
3709 /* If no log message, default it to the user message */
3711 if (*log_msgptr == NULL) *log_msgptr = *user_msgptr;
3714 acl_verify_message = NULL;
3722 /*************************************************
3723 * Get line from a literal ACL *
3724 *************************************************/
3726 /* This function is passed to acl_read() in order to extract individual lines
3727 of a literal ACL, which we access via static pointers. We can destroy the
3728 contents because this is called only once (the compiled ACL is remembered).
3730 This code is intended to treat the data in the same way as lines in the main
3731 Exim configuration file. That is:
3733 . Leading spaces are ignored.
3735 . A \ at the end of a line is a continuation - trailing spaces after the \
3736 are permitted (this is because I don't believe in making invisible things
3737 significant). Leading spaces on the continued part of a line are ignored.
3739 . Physical lines starting (significantly) with # are totally ignored, and
3740 may appear within a sequence of backslash-continued lines.
3742 . Blank lines are ignored, but will end a sequence of continuations.
3745 Returns: a pointer to the next line
3749 static uschar *acl_text; /* Current pointer in the text */
3750 static uschar *acl_text_end; /* Points one past the terminating '0' */
3758 /* This loop handles leading blank lines and comments. */
3762 while (isspace(*acl_text)) acl_text++; /* Leading spaces/empty lines */
3763 if (*acl_text == 0) return NULL; /* No more data */
3764 yield = acl_text; /* Potential data line */
3766 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3768 /* If we hit the end before a newline, we have the whole logical line. If
3769 it's a comment, there's no more data to be given. Otherwise, yield it. */
3771 if (*acl_text == 0) return (*yield == '#')? NULL : yield;
3773 /* After reaching a newline, end this loop if the physical line does not
3774 start with '#'. If it does, it's a comment, and the loop continues. */
3776 if (*yield != '#') break;
3779 /* This loop handles continuations. We know we have some real data, ending in
3780 newline. See if there is a continuation marker at the end (ignoring trailing
3781 white space). We know that *yield is not white space, so no need to test for
3782 cont > yield in the backwards scanning loop. */
3787 for (cont = acl_text - 1; isspace(*cont); cont--);
3789 /* If no continuation follows, we are done. Mark the end of the line and
3798 /* We have encountered a continuation. Skip over whitespace at the start of
3799 the next line, and indeed the whole of the next line or lines if they are
3804 while (*(++acl_text) == ' ' || *acl_text == '\t');
3805 if (*acl_text != '#') break;
3806 while (*(++acl_text) != 0 && *acl_text != '\n');
3809 /* We have the start of a continuation line. Move all the rest of the data
3810 to join onto the previous line, and then find its end. If the end is not a
3811 newline, we are done. Otherwise loop to look for another continuation. */
3813 memmove(cont, acl_text, acl_text_end - acl_text);
3814 acl_text_end -= acl_text - cont;
3816 while (*acl_text != 0 && *acl_text != '\n') acl_text++;
3817 if (*acl_text == 0) return yield;
3820 /* Control does not reach here */
3827 /*************************************************
3828 * Check access using an ACL *
3829 *************************************************/
3831 /* This function is called from address_check. It may recurse via
3832 acl_check_condition() - hence the use of a level to stop looping. The ACL is
3833 passed as a string which is expanded. A forced failure implies no access check
3834 is required. If the result is a single word, it is taken as the name of an ACL
3835 which is sought in the global ACL tree. Otherwise, it is taken as literal ACL
3836 text, complete with newlines, and parsed as such. In both cases, the ACL check
3837 is then run. This function uses an auxiliary function for acl_read() to call
3838 for reading individual lines of a literal ACL. This is acl_getline(), which
3839 appears immediately above.
3842 where where called from
3843 addr address item when called from RCPT; otherwise NULL
3844 s the input string; NULL is the same as an empty ACL => DENY
3845 user_msgptr where to put a user error (for SMTP response)
3846 log_msgptr where to put a logging message (not for SMTP response)
3848 Returns: OK access is granted
3849 DISCARD access is apparently granted...
3850 FAIL access is denied
3851 FAIL_DROP access is denied; drop the connection
3852 DEFER can't tell at the moment
3857 acl_check_internal(int where, address_item *addr, uschar *s,
3858 uschar **user_msgptr, uschar **log_msgptr)
3861 acl_block *acl = NULL;
3862 uschar *acl_name = US"inline ACL";
3865 /* Catch configuration loops */
3869 *log_msgptr = US"ACL nested too deep: possible loop";
3875 HDEBUG(D_acl) debug_printf_indent("ACL is NULL: implicit DENY\n");
3879 /* At top level, we expand the incoming string. At lower levels, it has already
3880 been expanded as part of condition processing. */
3884 if (!(ss = expand_string(s)))
3886 if (expand_string_forcedfail) return OK;
3887 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s", s,
3888 expand_string_message);
3894 while (isspace(*ss))ss++;
3896 /* If we can't find a named ACL, the default is to parse it as an inline one.
3897 (Unless it begins with a slash; non-existent files give rise to an error.) */
3901 /* Handle the case of a string that does not contain any spaces. Look for a
3902 named ACL among those read from the configuration, or a previously read file.
3903 It is possible that the pointer to the ACL is NULL if the configuration
3904 contains a name with no data. If not found, and the text begins with '/',
3905 read an ACL from a file, and save it so it can be re-used. */
3907 if (Ustrchr(ss, ' ') == NULL)
3909 tree_node *t = tree_search(acl_anchor, ss);
3912 acl = (acl_block *)(t->data.ptr);
3915 HDEBUG(D_acl) debug_printf_indent("ACL \"%s\" is empty: implicit DENY\n", ss);
3918 acl_name = string_sprintf("ACL \"%s\"", ss);
3919 HDEBUG(D_acl) debug_printf_indent("using ACL \"%s\"\n", ss);
3922 else if (*ss == '/')
3924 struct stat statbuf;
3925 fd = Uopen(ss, O_RDONLY, 0);
3928 *log_msgptr = string_sprintf("failed to open ACL file \"%s\": %s", ss,
3933 if (fstat(fd, &statbuf) != 0)
3935 *log_msgptr = string_sprintf("failed to fstat ACL file \"%s\": %s", ss,
3940 acl_text = store_get(statbuf.st_size + 1);
3941 acl_text_end = acl_text + statbuf.st_size + 1;
3943 if (read(fd, acl_text, statbuf.st_size) != statbuf.st_size)
3945 *log_msgptr = string_sprintf("failed to read ACL file \"%s\": %s",
3946 ss, strerror(errno));
3949 acl_text[statbuf.st_size] = 0;
3952 acl_name = string_sprintf("ACL \"%s\"", ss);
3953 HDEBUG(D_acl) debug_printf_indent("read ACL from file %s\n", ss);
3957 /* Parse an ACL that is still in text form. If it came from a file, remember it
3958 in the ACL tree, having read it into the POOL_PERM store pool so that it
3959 persists between multiple messages. */
3963 int old_pool = store_pool;
3964 if (fd >= 0) store_pool = POOL_PERM;
3965 acl = acl_read(acl_getline, log_msgptr);
3966 store_pool = old_pool;
3967 if (acl == NULL && *log_msgptr != NULL) return ERROR;
3970 tree_node *t = store_get_perm(sizeof(tree_node) + Ustrlen(ss));
3971 Ustrcpy(t->name, ss);
3973 (void)tree_insertnode(&acl_anchor, t);
3977 /* Now we have an ACL to use. It's possible it may be NULL. */
3982 int basic_errno = 0;
3983 BOOL endpass_seen = FALSE;
3984 BOOL acl_quit_check = acl_level == 0
3985 && (where == ACL_WHERE_QUIT || where == ACL_WHERE_NOTQUIT);
3987 *log_msgptr = *user_msgptr = NULL;
3988 acl_temp_details = FALSE;
3990 HDEBUG(D_acl) debug_printf_indent("processing \"%s\"\n", verbs[acl->verb]);
3992 /* Clear out any search error message from a previous check before testing
3995 search_error_message = NULL;
3996 cond = acl_check_condition(acl->verb, acl->condition, where, addr, acl_level,
3997 &endpass_seen, user_msgptr, log_msgptr, &basic_errno);
3999 /* Handle special returns: DEFER causes a return except on a WARN verb;
4000 ERROR always causes a return. */
4005 HDEBUG(D_acl) debug_printf_indent("%s: condition test deferred in %s\n", verbs[acl->verb], acl_name);
4006 if (basic_errno != ERRNO_CALLOUTDEFER)
4008 if (search_error_message != NULL && *search_error_message != 0)
4009 *log_msgptr = search_error_message;
4010 if (smtp_return_error_details) acl_temp_details = TRUE;
4014 acl_temp_details = TRUE;
4016 if (acl->verb != ACL_WARN) return DEFER;
4019 default: /* Paranoia */
4021 HDEBUG(D_acl) debug_printf_indent("%s: condition test error in %s\n", verbs[acl->verb], acl_name);
4025 HDEBUG(D_acl) debug_printf_indent("%s: condition test succeeded in %s\n",
4026 verbs[acl->verb], acl_name);
4030 HDEBUG(D_acl) debug_printf_indent("%s: condition test failed in %s\n", verbs[acl->verb], acl_name);
4033 /* DISCARD and DROP can happen only from a nested ACL condition, and
4034 DISCARD can happen only for an "accept" or "discard" verb. */
4037 HDEBUG(D_acl) debug_printf_indent("%s: condition test yielded \"discard\" in %s\n",
4038 verbs[acl->verb], acl_name);
4042 HDEBUG(D_acl) debug_printf_indent("%s: condition test yielded \"drop\" in %s\n",
4043 verbs[acl->verb], acl_name);
4047 /* At this point, cond for most verbs is either OK or FAIL or (as a result of
4048 a nested ACL condition) FAIL_DROP. However, for WARN, cond may be DEFER, and
4049 for ACCEPT and DISCARD, it may be DISCARD after a nested ACL call. */
4054 if (cond == OK || cond == DISCARD)
4056 HDEBUG(D_acl) debug_printf_indent("end of %s: ACCEPT\n", acl_name);
4061 HDEBUG(D_acl) debug_printf_indent("accept: endpass encountered - denying access\n");
4069 HDEBUG(D_acl) debug_printf_indent("end of %s: DEFER\n", acl_name);
4070 if (acl_quit_check) goto badquit;
4071 acl_temp_details = TRUE;
4079 HDEBUG(D_acl) debug_printf_indent("end of %s: DENY\n", acl_name);
4080 if (acl_quit_check) goto badquit;
4086 if (cond == OK || cond == DISCARD)
4088 HDEBUG(D_acl) debug_printf_indent("end of %s: DISCARD\n", acl_name);
4089 if (acl_quit_check) goto badquit;
4094 HDEBUG(D_acl) debug_printf_indent("discard: endpass encountered - denying access\n");
4102 HDEBUG(D_acl) debug_printf_indent("end of %s: DROP\n", acl_name);
4103 if (acl_quit_check) goto badquit;
4111 HDEBUG(D_acl) debug_printf_indent("end of %s: not OK\n", acl_name);
4112 if (acl_quit_check) goto badquit;
4119 acl_warn(where, *user_msgptr, *log_msgptr);
4120 else if (cond == DEFER && LOGGING(acl_warn_skipped))
4121 log_write(0, LOG_MAIN, "%s Warning: ACL \"warn\" statement skipped: "
4122 "condition test deferred%s%s", host_and_ident(TRUE),
4123 (*log_msgptr == NULL)? US"" : US": ",
4124 (*log_msgptr == NULL)? US"" : *log_msgptr);
4125 *log_msgptr = *user_msgptr = NULL; /* In case implicit DENY follows */
4129 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown verb %d",
4134 /* Pass to the next ACL item */
4139 /* We have reached the end of the ACL. This is an implicit DENY. */
4141 HDEBUG(D_acl) debug_printf_indent("end of %s: implicit DENY\n", acl_name);
4145 *log_msgptr = string_sprintf("QUIT or not-QUIT toplevel ACL may not fail "
4146 "('%s' verb used incorrectly)", verbs[acl->verb]);
4153 /* Same args as acl_check_internal() above, but the string s is
4154 the name of an ACL followed optionally by up to 9 space-separated arguments.
4155 The name and args are separately expanded. Args go into $acl_arg globals. */
4157 acl_check_wargs(int where, address_item *addr, const uschar *s,
4158 uschar **user_msgptr, uschar **log_msgptr)
4161 uschar * tmp_arg[9]; /* must match acl_arg[] */
4162 uschar * sav_arg[9]; /* must match acl_arg[] */
4168 if (!(tmp = string_dequote(&s)) || !(name = expand_string(tmp)))
4171 for (i = 0; i < 9; i++)
4173 while (*s && isspace(*s)) s++;
4175 if (!(tmp = string_dequote(&s)) || !(tmp_arg[i] = expand_string(tmp)))
4182 sav_narg = acl_narg;
4184 for (i = 0; i < acl_narg; i++)
4186 sav_arg[i] = acl_arg[i];
4187 acl_arg[i] = tmp_arg[i];
4191 sav_arg[i] = acl_arg[i];
4192 acl_arg[i++] = NULL;
4196 ret = acl_check_internal(where, addr, name, user_msgptr, log_msgptr);
4199 acl_narg = sav_narg;
4200 for (i = 0; i < 9; i++) acl_arg[i] = sav_arg[i];
4204 if (expand_string_forcedfail) return ERROR;
4205 *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s",
4206 tmp, expand_string_message);
4207 return search_find_defer?DEFER:ERROR;
4212 /*************************************************
4213 * Check access using an ACL *
4214 *************************************************/
4216 /* Alternate interface for ACL, used by expansions */
4218 acl_eval(int where, uschar *s, uschar **user_msgptr, uschar **log_msgptr)
4221 address_item *addr = NULL;
4224 *user_msgptr = *log_msgptr = NULL;
4225 sender_verified_failed = NULL;
4226 ratelimiters_cmd = NULL;
4227 log_reject_target = LOG_MAIN|LOG_REJECT;
4229 if (where == ACL_WHERE_RCPT)
4231 adb = address_defaults;
4233 addr->address = expand_string(US"$local_part@$domain");
4234 addr->domain = deliver_domain;
4235 addr->local_part = deliver_localpart;
4236 addr->cc_local_part = deliver_localpart;
4237 addr->lc_local_part = deliver_localpart;
4241 rc = acl_check_internal(where, addr, s, user_msgptr, log_msgptr);
4248 /* This is the external interface for ACL checks. It sets up an address and the
4249 expansions for $domain and $local_part when called after RCPT, then calls
4250 acl_check_internal() to do the actual work.
4253 where ACL_WHERE_xxxx indicating where called from
4254 recipient RCPT address for RCPT check, else NULL
4255 s the input string; NULL is the same as an empty ACL => DENY
4256 user_msgptr where to put a user error (for SMTP response)
4257 log_msgptr where to put a logging message (not for SMTP response)
4259 Returns: OK access is granted by an ACCEPT verb
4260 DISCARD access is granted by a DISCARD verb
4261 FAIL access is denied
4262 FAIL_DROP access is denied; drop the connection
4263 DEFER can't tell at the moment
4266 int acl_where = ACL_WHERE_UNKNOWN;
4269 acl_check(int where, uschar *recipient, uschar *s, uschar **user_msgptr,
4270 uschar **log_msgptr)
4274 address_item *addr = NULL;
4276 *user_msgptr = *log_msgptr = NULL;
4277 sender_verified_failed = NULL;
4278 ratelimiters_cmd = NULL;
4279 log_reject_target = LOG_MAIN|LOG_REJECT;
4281 #ifndef DISABLE_PRDR
4282 if (where==ACL_WHERE_RCPT || where==ACL_WHERE_VRFY || where==ACL_WHERE_PRDR)
4284 if (where==ACL_WHERE_RCPT || where==ACL_WHERE_VRFY)
4287 adb = address_defaults;
4289 addr->address = recipient;
4290 if (deliver_split_address(addr) == DEFER)
4292 *log_msgptr = US"defer in percent_hack_domains check";
4296 if ((addr->prop.utf8_msg = message_smtputf8))
4298 addr->prop.utf8_downcvt = message_utf8_downconvert == 1;
4299 addr->prop.utf8_downcvt_maybe = message_utf8_downconvert == -1;
4302 deliver_domain = addr->domain;
4303 deliver_localpart = addr->local_part;
4308 rc = acl_check_internal(where, addr, s, user_msgptr, log_msgptr);
4310 acl_where = ACL_WHERE_UNKNOWN;
4312 /* Cutthrough - if requested,
4313 and WHERE_RCPT and not yet opened conn as result of recipient-verify,
4314 and rcpt acl returned accept,
4315 and first recipient (cancel on any subsequents)
4316 open one now and run it up to RCPT acceptance.
4317 A failed verify should cancel cutthrough request,
4318 and will pass the fail to the originator.
4319 Initial implementation: dual-write to spool.
4320 Assume the rxd datastream is now being copied byte-for-byte to an open cutthrough connection.
4322 Cease cutthrough copy on rxd final dot; do not send one.
4324 On a data acl, if not accept and a cutthrough conn is open, hard-close it (no SMTP niceness).
4326 On data acl accept, terminate the dataphase on an open cutthrough conn. If accepted or
4327 perm-rejected, reflect that to the original sender - and dump the spooled copy.
4328 If temp-reject, close the conn (and keep the spooled copy).
4329 If conn-failure, no action (and keep the spooled copy).
4333 case ACL_WHERE_RCPT:
4334 #ifndef DISABLE_PRDR
4335 case ACL_WHERE_PRDR:
4337 if (host_checking_callout) /* -bhc mode */
4338 cancel_cutthrough_connection("host-checking mode");
4341 && cutthrough.delivery
4342 && rcpt_count > cutthrough.nrcpt
4343 && (rc = open_cutthrough_connection(addr)) == DEFER
4345 if (cutthrough.defer_pass)
4347 uschar * s = addr->message;
4348 /* Horrid kludge to recover target's SMTP message */
4350 do --s; while (!isdigit(*s));
4351 if (*--s && isdigit(*s) && *--s && isdigit(*s)) *user_msgptr = s;
4352 acl_temp_details = TRUE;
4356 HDEBUG(D_acl) debug_printf_indent("cutthrough defer; will spool\n");
4361 case ACL_WHERE_PREDATA:
4363 cutthrough_predata();
4365 cancel_cutthrough_connection("predata acl not ok");
4368 case ACL_WHERE_QUIT:
4369 case ACL_WHERE_NOTQUIT:
4370 cancel_cutthrough_connection("quit or notquit");
4377 deliver_domain = deliver_localpart = deliver_address_data =
4378 sender_address_data = NULL;
4380 /* A DISCARD response is permitted only for message ACLs, excluding the PREDATA
4381 ACL, which is really in the middle of an SMTP command. */
4385 if (where > ACL_WHERE_NOTSMTP || where == ACL_WHERE_PREDATA)
4387 log_write(0, LOG_MAIN|LOG_PANIC, "\"discard\" verb not allowed in %s "
4388 "ACL", acl_wherenames[where]);
4394 /* A DROP response is not permitted from MAILAUTH */
4396 if (rc == FAIL_DROP && where == ACL_WHERE_MAILAUTH)
4398 log_write(0, LOG_MAIN|LOG_PANIC, "\"drop\" verb not allowed in %s "
4399 "ACL", acl_wherenames[where]);
4403 /* Before giving a response, take a look at the length of any user message, and
4404 split it up into multiple lines if possible. */
4406 *user_msgptr = string_split_message(*user_msgptr);
4407 if (fake_response != OK)
4408 fake_response_text = string_split_message(fake_response_text);
4414 /*************************************************
4415 * Create ACL variable *
4416 *************************************************/
4418 /* Create an ACL variable or reuse an existing one. ACL variables are in a
4419 binary tree (see tree.c) with acl_var_c and acl_var_m as root nodes.
4422 name pointer to the variable's name, starting with c or m
4424 Returns the pointer to variable's tree node
4428 acl_var_create(uschar * name)
4430 tree_node * node, ** root = name[0] == 'c' ? &acl_var_c : &acl_var_m;
4431 if (!(node = tree_search(*root, name)))
4433 node = store_get(sizeof(tree_node) + Ustrlen(name));
4434 Ustrcpy(node->name, name);
4435 (void)tree_insertnode(root, node);
4437 node->data.ptr = NULL;
4443 /*************************************************
4444 * Write an ACL variable in spool format *
4445 *************************************************/
4447 /* This function is used as a callback for tree_walk when writing variables to
4448 the spool file. To retain spool file compatibility, what is written is -aclc or
4449 -aclm followed by the rest of the name and the data length, space separated,
4450 then the value itself, starting on a new line, and terminated by an additional
4451 newline. When we had only numbered ACL variables, the first line might look
4452 like this: "-aclc 5 20". Now it might be "-aclc foo 20" for the variable called
4456 name of the variable
4457 value of the variable
4458 ctx FILE pointer (as a void pointer)
4464 acl_var_write(uschar *name, uschar *value, void *ctx)
4466 FILE *f = (FILE *)ctx;
4467 fprintf(f, "-acl%c %s %d\n%s\n", name[0], name+1, Ustrlen(value), value);