1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) The Exim Maintainers 2020 - 2022 */
6 /* Copyright (c) University of Cambridge 1995 - 2023 */
7 /* See the file NOTICE for conditions of use and distribution. */
8 /* SPDX-License-Identifier: GPL-2.0-or-later */
10 /* Functions concerned with verifying things. The original code for callout
11 caching was contributed by Kevin Fleming (but I hacked it around a bit). */
15 #include "transports/smtp.h"
17 #define CUTTHROUGH_CMD_TIMEOUT 30 /* timeout for cutthrough-routing calls */
18 #define CUTTHROUGH_DATA_TIMEOUT 60 /* timeout for cutthrough-routing calls */
19 static smtp_context ctctx;
20 uschar ctbuffer[8192];
23 static uschar cutthrough_response(client_conn_ctx *, char, uschar **, int);
27 /*************************************************
28 * Retrieve a callout cache record *
29 *************************************************/
31 /* If a record exists, check whether it has expired.
34 dbm_file an open hints file
36 type "address" or "domain"
37 positive_expire expire time for positive records
38 negative_expire expire time for negative records
40 Returns: the cache record if a non-expired one exists, else NULL
43 static dbdata_callout_cache *
44 get_callout_cache_record(open_db *dbm_file, const uschar *key, uschar *type,
45 int positive_expire, int negative_expire)
50 dbdata_callout_cache *cache_record;
52 if (!(cache_record = dbfn_read_with_length(dbm_file, key, &length)))
54 HDEBUG(D_verify) debug_printf_indent("callout cache: no %s record found for %s\n", type, key);
58 /* We treat a record as "negative" if its result field is not positive, or if
59 it is a domain record and the postmaster field is negative. */
61 negative = cache_record->result != ccache_accept ||
62 (type[0] == 'd' && cache_record->postmaster_result == ccache_reject);
63 expire = negative? negative_expire : positive_expire;
66 if (now - cache_record->time_stamp > expire)
68 HDEBUG(D_verify) debug_printf_indent("callout cache: %s record expired for %s\n", type, key);
72 /* If this is a non-reject domain record, check for the obsolete format version
73 that doesn't have the postmaster and random timestamps, by looking at the
74 length. If so, copy it to a new-style block, replicating the record's
75 timestamp. Then check the additional timestamps. (There's no point wasting
76 effort if connections are rejected.) */
78 if (type[0] == 'd' && cache_record->result != ccache_reject)
80 if (length == sizeof(dbdata_callout_cache_obs))
82 dbdata_callout_cache * new = store_get(sizeof(dbdata_callout_cache), GET_UNTAINTED);
83 memcpy(new, cache_record, length);
84 new->postmaster_stamp = new->random_stamp = new->time_stamp;
88 if (now - cache_record->postmaster_stamp > expire)
89 cache_record->postmaster_result = ccache_unknown;
91 if (now - cache_record->random_stamp > expire)
92 cache_record->random_result = ccache_unknown;
95 HDEBUG(D_verify) debug_printf_indent("callout cache: found %s record for %s\n", type, key);
101 /* Check the callout cache.
102 Options * pm_mailfrom may be modified by cache partial results.
104 Return: TRUE if result found
108 cached_callout_lookup(address_item * addr, uschar * address_key,
109 uschar * from_address, int * opt_ptr, uschar ** pm_ptr,
110 int * yield, uschar ** failure_ptr,
111 dbdata_callout_cache * new_domain_record, int * old_domain_res)
113 int options = *opt_ptr;
115 open_db *dbm_file = NULL;
117 /* Open the callout cache database, if it exists, for reading only at this
118 stage, unless caching has been disabled. */
120 if (options & vopt_callout_no_cache)
122 HDEBUG(D_verify) debug_printf_indent("callout cache: disabled by no_cache\n");
124 else if (!(dbm_file = dbfn_open(US"callout", O_RDWR, &dbblock, FALSE, TRUE)))
126 HDEBUG(D_verify) debug_printf_indent("callout cache: not available\n");
130 /* If a cache database is available see if we can avoid the need to do an
131 actual callout by making use of previously-obtained data. */
133 dbdata_callout_cache_address * cache_address_record;
134 dbdata_callout_cache * cache_record = get_callout_cache_record(dbm_file,
135 addr->domain, US"domain",
136 callout_cache_domain_positive_expire, callout_cache_domain_negative_expire);
138 /* If an unexpired cache record was found for this domain, see if the callout
139 process can be short-circuited. */
143 /* In most cases, if an early command (up to and including MAIL FROM:<>)
144 was rejected, there is no point carrying on. The callout fails. However, if
145 we are doing a recipient verification with use_sender or use_postmaster
146 set, a previous failure of MAIL FROM:<> doesn't count, because this time we
147 will be using a non-empty sender. We have to remember this situation so as
148 not to disturb the cached domain value if this whole verification succeeds
149 (we don't want it turning into "accept"). */
151 *old_domain_res = cache_record->result;
153 if ( cache_record->result == ccache_reject
154 || *from_address == 0 && cache_record->result == ccache_reject_mfnull)
157 debug_printf_indent("callout cache: domain gave initial rejection, or "
158 "does not accept HELO or MAIL FROM:<>\n");
159 setflag(addr, af_verify_nsfail);
160 addr->user_message = US"(result of an earlier callout reused).";
162 *failure_ptr = US"mail";
163 dbfn_close(dbm_file);
167 /* If a previous check on a "random" local part was accepted, we assume
168 that the server does not do any checking on local parts. There is therefore
169 no point in doing the callout, because it will always be successful. If a
170 random check previously failed, arrange not to do it again, but preserve
171 the data in the new record. If a random check is required but hasn't been
172 done, skip the remaining cache processing. */
174 if (options & vopt_callout_random) switch(cache_record->random_result)
178 debug_printf_indent("callout cache: domain accepts random addresses\n");
179 *failure_ptr = US"random";
180 dbfn_close(dbm_file);
181 return TRUE; /* Default yield is OK */
185 debug_printf_indent("callout cache: domain rejects random addresses\n");
186 *opt_ptr = options & ~vopt_callout_random;
187 new_domain_record->random_result = ccache_reject;
188 new_domain_record->random_stamp = cache_record->random_stamp;
193 debug_printf_indent("callout cache: need to check random address handling "
194 "(not cached or cache expired)\n");
195 dbfn_close(dbm_file);
199 /* If a postmaster check is requested, but there was a previous failure,
200 there is again no point in carrying on. If a postmaster check is required,
201 but has not been done before, we are going to have to do a callout, so skip
202 remaining cache processing. */
206 if (cache_record->postmaster_result == ccache_reject)
208 setflag(addr, af_verify_pmfail);
210 debug_printf_indent("callout cache: domain does not accept "
211 "RCPT TO:<postmaster@domain>\n");
213 *failure_ptr = US"postmaster";
214 setflag(addr, af_verify_pmfail);
215 addr->user_message = US"(result of earlier verification reused).";
216 dbfn_close(dbm_file);
219 if (cache_record->postmaster_result == ccache_unknown)
222 debug_printf_indent("callout cache: need to check RCPT "
223 "TO:<postmaster@domain> (not cached or cache expired)\n");
224 dbfn_close(dbm_file);
228 /* If cache says OK, set pm_mailfrom NULL to prevent a redundant
229 postmaster check if the address itself has to be checked. Also ensure
230 that the value in the cache record is preserved (with its old timestamp).
233 HDEBUG(D_verify) debug_printf_indent("callout cache: domain accepts RCPT "
234 "TO:<postmaster@domain>\n");
236 new_domain_record->postmaster_result = ccache_accept;
237 new_domain_record->postmaster_stamp = cache_record->postmaster_stamp;
241 /* We can't give a result based on information about the domain. See if there
242 is an unexpired cache record for this specific address (combined with the
243 sender address if we are doing a recipient callout with a non-empty sender).
246 if (!(cache_address_record = (dbdata_callout_cache_address *)
247 get_callout_cache_record(dbm_file, address_key, US"address",
248 callout_cache_positive_expire, callout_cache_negative_expire)))
250 dbfn_close(dbm_file);
254 if (cache_address_record->result == ccache_accept)
257 debug_printf_indent("callout cache: address record is positive\n");
262 debug_printf_indent("callout cache: address record is negative\n");
263 addr->user_message = US"Previous (cached) callout verification failure";
264 *failure_ptr = US"recipient";
268 /* Close the cache database while we actually do the callout for real. */
270 dbfn_close(dbm_file);
277 /* Write results to callout cache
280 cache_callout_write(dbdata_callout_cache * dom_rec, const uschar * domain,
281 int done, dbdata_callout_cache_address * addr_rec, uschar * address_key)
284 open_db *dbm_file = NULL;
286 /* If we get here with done == TRUE, a successful callout happened, and yield
287 will be set OK or FAIL according to the response to the RCPT command.
288 Otherwise, we looped through the hosts but couldn't complete the business.
289 However, there may be domain-specific information to cache in both cases.
291 The value of the result field in the new_domain record is ccache_unknown if
292 there was an error before or with MAIL FROM:, and errno was not zero,
293 implying some kind of I/O error. We don't want to write the cache in that case.
294 Otherwise the value is ccache_accept, ccache_reject, or ccache_reject_mfnull. */
296 if (dom_rec->result != ccache_unknown)
297 if (!(dbm_file = dbfn_open(US"callout", O_RDWR|O_CREAT, &dbblock, FALSE, TRUE)))
299 HDEBUG(D_verify) debug_printf_indent("callout cache: not available\n");
303 (void)dbfn_write(dbm_file, domain, dom_rec,
304 (int)sizeof(dbdata_callout_cache));
305 HDEBUG(D_verify) debug_printf_indent("wrote callout cache domain record for %s:\n"
306 " result=%d postmaster=%d random=%d\n",
309 dom_rec->postmaster_result,
310 dom_rec->random_result);
313 /* If a definite result was obtained for the callout, cache it unless caching
316 if (done && addr_rec->result != ccache_unknown)
319 dbm_file = dbfn_open(US"callout", O_RDWR|O_CREAT, &dbblock, FALSE, TRUE);
322 HDEBUG(D_verify) debug_printf_indent("no callout cache available\n");
326 (void)dbfn_write(dbm_file, address_key, addr_rec,
327 (int)sizeof(dbdata_callout_cache_address));
328 HDEBUG(D_verify) debug_printf_indent("wrote %s callout cache address record for %s\n",
329 addr_rec->result == ccache_accept ? "positive" : "negative",
334 if (dbm_file) dbfn_close(dbm_file);
338 /* Cutthrough-multi. If the existing cached cutthrough connection matches
339 the one we would make for a subsequent recipient, use it. Send the RCPT TO
340 and check the result, nonpipelined as it may be wanted immediately for
341 recipient-verification.
343 It seems simpler to deal with this case separately from the main callout loop.
344 We will need to remember it has sent, or not, so that rcpt-acl tail code
345 can do it there for the non-rcpt-verify case. For this we keep an addresscount.
347 Return: TRUE for a definitive result for the recipient
350 cutthrough_multi(address_item * addr, host_item * host_list,
351 transport_feedback * tf, int * yield)
355 if (addr->transport == cutthrough.addr.transport)
356 for (host_item * host = host_list; host; host = host->next)
357 if (Ustrcmp(host->address, cutthrough.host.address) == 0)
360 uschar *interface = NULL; /* Outgoing interface to use; NULL => any */
363 deliver_host = host->name;
364 deliver_host_address = host->address;
365 deliver_host_port = host->port;
366 deliver_domain = addr->domain;
367 transport_name = addr->transport->name;
369 host_af = Ustrchr(host->address, ':') ? AF_INET6 : AF_INET;
371 if ( !smtp_get_interface(tf->interface, host_af, addr, &interface,
373 || !smtp_get_port(tf->port, addr, &port, US"callout")
375 log_write(0, LOG_MAIN|LOG_PANIC, "<%s>: %s", addr->address,
378 smtp_port_for_connect(host, port);
380 if ( ( interface == cutthrough.interface
382 && cutthrough.interface
383 && Ustrcmp(interface, cutthrough.interface) == 0
385 && host->port == cutthrough.host.port
388 uschar * resp = NULL;
390 /* Match! Send the RCPT TO, set done from the response */
392 smtp_write_command(&ctctx, SCMD_FLUSH, "RCPT TO:<%.1000s>\r\n",
393 transport_rcpt_address(addr,
394 addr->transport->rcpt_include_affixes)) >= 0
395 && cutthrough_response(&cutthrough.cctx, '2', &resp,
396 CUTTHROUGH_DATA_TIMEOUT) == '2';
398 /* This would go horribly wrong if a callout fail was ignored by ACL.
399 We punt by abandoning cutthrough on a reject, like the
404 address_item * na = store_get(sizeof(address_item), GET_UNTAINTED);
405 *na = cutthrough.addr;
406 cutthrough.addr = *addr;
407 cutthrough.addr.host_used = &cutthrough.host;
408 cutthrough.addr.next = na;
414 cancel_cutthrough_connection(TRUE, US"recipient rejected");
415 if (!resp || errno == ETIMEDOUT)
417 HDEBUG(D_verify) debug_printf("SMTP timeout\n");
422 Ustrcpy(resp, US"connection dropped");
425 string_sprintf("response to \"%s\" was: %s",
426 big_buffer, string_printing(resp));
429 string_sprintf("Callout verification failed:\n%s", resp);
431 /* Hard rejection ends the process */
433 if (resp[0] == '5') /* Address rejected */
441 break; /* host_list */
444 cancel_cutthrough_connection(TRUE, US"incompatible connection");
451 /* A rcpt callout, or cached record of one, verified the address.
452 Set $domain_data and $local_part_data to detainted versions.
455 callout_verified_rcpt(const address_item * addr)
457 address_item a = {.address = addr->address};
458 if (deliver_split_address(&a) != OK) return;
459 deliver_localpart_data = string_copy_taint(a.local_part, GET_UNTAINTED);
460 deliver_domain_data = string_copy_taint(a.domain, GET_UNTAINTED);
464 /*************************************************
465 * Do callout verification for an address *
466 *************************************************/
468 /* This function is called from verify_address() when the address has routed to
469 a host list, and a callout has been requested. Callouts are expensive; that is
470 why a cache is used to improve the efficiency.
473 addr the address that's been routed
474 host_list the list of hosts to try
475 tf the transport feedback block
477 ifstring "interface" option from transport, or NULL
478 portstring "port" option from transport, or NULL
479 protocolstring "protocol" option from transport, or NULL
480 callout the per-command callout timeout
481 callout_overall the overall callout timeout (if < 0 use 4*callout)
482 callout_connect the callout connection timeout (if < 0 use callout)
483 options the verification options - these bits are used:
484 vopt_is_recipient => this is a recipient address
485 vopt_callout_no_cache => don't use callout cache
486 vopt_callout_fullpm => if postmaster check, do full one
487 vopt_callout_random => do the "random" thing
488 vopt_callout_recipsender => use real sender for recipient
489 vopt_callout_recippmaster => use postmaster for recipient
490 vopt_callout_hold => lazy close connection
491 se_mailfrom MAIL FROM address for sender verify; NULL => ""
492 pm_mailfrom if non-NULL, do the postmaster check with this sender
494 Returns: OK/FAIL/DEFER
498 do_callout(address_item *addr, host_item *host_list, transport_feedback *tf,
499 int callout, int callout_overall, int callout_connect, int options,
500 uschar *se_mailfrom, uschar *pm_mailfrom)
503 int old_domain_cache_result = ccache_accept;
506 uschar *from_address;
507 uschar *random_local_part = NULL;
508 const uschar *save_deliver_domain = deliver_domain;
509 uschar **failure_ptr = options & vopt_is_recipient
510 ? &recipient_verify_failure : &sender_verify_failure;
511 dbdata_callout_cache new_domain_record;
512 dbdata_callout_cache_address new_address_record;
513 time_t callout_start_time;
515 new_domain_record.result = ccache_unknown;
516 new_domain_record.postmaster_result = ccache_unknown;
517 new_domain_record.random_result = ccache_unknown;
519 memset(&new_address_record, 0, sizeof(new_address_record));
521 /* For a recipient callout, the key used for the address cache record must
522 include the sender address if we are using the real sender in the callout,
523 because that may influence the result of the callout. */
525 if (options & vopt_is_recipient)
526 if (options & vopt_callout_recipsender)
528 from_address = sender_address;
529 address_key = string_sprintf("%s/<%s>", addr->address, sender_address);
530 if (cutthrough.delivery) options |= vopt_callout_no_cache;
532 else if (options & vopt_callout_recippmaster)
534 from_address = string_sprintf("postmaster@%s", qualify_domain_sender);
535 address_key = string_sprintf("%s/<postmaster@%s>", addr->address,
536 qualify_domain_sender);
541 address_key = addr->address;
544 /* For a sender callout, we must adjust the key if the mailfrom address is not
549 from_address = se_mailfrom ? se_mailfrom : US"";
550 address_key = *from_address
551 ? string_sprintf("%s/<%s>", addr->address, from_address) : addr->address;
554 if (cached_callout_lookup(addr, address_key, from_address,
555 &options, &pm_mailfrom, &yield, failure_ptr,
556 &new_domain_record, &old_domain_cache_result))
558 cancel_cutthrough_connection(TRUE, US"cache-hit");
562 if (!addr->transport)
564 HDEBUG(D_verify) debug_printf("cannot callout via null transport\n");
567 else if (Ustrcmp(addr->transport->driver_name, "smtp") != 0)
568 log_write(0, LOG_MAIN|LOG_PANIC|LOG_CONFIG_FOR, "callout transport '%s': %s is non-smtp",
569 addr->transport->name, addr->transport->driver_name);
572 smtp_transport_options_block *ob =
573 (smtp_transport_options_block *)addr->transport->options_block;
574 smtp_context * sx = NULL;
576 /* The information wasn't available in the cache, so we have to do a real
577 callout and save the result in the cache for next time, unless no_cache is set,
578 or unless we have a previously cached negative random result. If we are to test
579 with a random local part, ensure that such a local part is available. If not,
580 log the fact, but carry on without randomising. */
582 if (options & vopt_callout_random && callout_random_local_part)
583 if (!(random_local_part = expand_string(callout_random_local_part)))
584 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand "
585 "callout_random_local_part: %s", expand_string_message);
587 /* Compile regex' used by client-side smtp */
591 /* Default the connect and overall callout timeouts if not set, and record the
592 time we are starting so that we can enforce it. */
594 if (callout_overall < 0) callout_overall = 4 * callout;
595 if (callout_connect < 0) callout_connect = callout;
596 callout_start_time = time(NULL);
598 /* Before doing a real callout, if this is an SMTP connection, flush the SMTP
599 output because a callout might take some time. When PIPELINING is active and
600 there are many recipients, the total time for doing lots of callouts can add up
601 and cause the client to time out. So in this case we forgo the PIPELINING
604 if (smtp_out && !f.disable_callout_flush) mac_smtp_fflush();
606 clearflag(addr, af_verify_pmfail); /* postmaster callout flag */
607 clearflag(addr, af_verify_nsfail); /* null sender callout flag */
609 /* cutthrough-multi: if a nonfirst rcpt has the same routing as the first,
610 and we are holding a cutthrough conn open, we can just append the rcpt to
611 that conn for verification purposes (and later delivery also). Simplest
612 coding means skipping this whole loop and doing the append separately. */
614 /* Can we re-use an open cutthrough connection? */
615 if ( cutthrough.cctx.sock >= 0
616 && (options & (vopt_callout_recipsender | vopt_callout_recippmaster))
617 == vopt_callout_recipsender
618 && !random_local_part
621 done = cutthrough_multi(addr, host_list, tf, &yield);
623 /* If we did not use a cached connection, make connections to the hosts
624 and do real callouts. The list of hosts is passed in as an argument. */
626 for (host_item * host = host_list; host && !done; host = host->next)
630 uschar * interface = NULL; /* Outgoing interface to use; NULL => any */
634 DEBUG(D_verify) debug_printf("no IP address for host name %s: skipping\n",
639 /* Check the overall callout timeout */
641 if (time(NULL) - callout_start_time >= callout_overall)
643 HDEBUG(D_verify) debug_printf("overall timeout for callout exceeded\n");
647 /* Set IPv4 or IPv6 */
649 host_af = Ustrchr(host->address, ':') ? AF_INET6 : AF_INET;
651 /* Expand and interpret the interface and port strings. The latter will not
652 be used if there is a host-specific port (e.g. from a manualroute router).
653 This has to be delayed till now, because they may expand differently for
654 different hosts. If there's a failure, log it, but carry on with the
657 deliver_host = host->name;
658 deliver_host_address = host->address;
659 deliver_host_port = host->port;
660 deliver_domain = addr->domain;
661 transport_name = addr->transport->name;
663 if ( !smtp_get_interface(tf->interface, host_af, addr, &interface,
665 || !smtp_get_port(tf->port, addr, &port, US"callout")
667 log_write(0, LOG_MAIN|LOG_PANIC, "<%s>: %s", addr->address,
670 if (!sx) sx = store_get(sizeof(*sx), GET_TAINTED); /* tainted buffers */
671 memset(sx, 0, sizeof(*sx));
673 sx->addrlist = sx->first_addr = addr;
674 sx->conn_args.host = host;
675 sx->conn_args.host_af = host_af,
677 sx->conn_args.interface = interface;
678 sx->helo_data = tf->helo_data;
679 sx->conn_args.tblock = addr->transport;
680 sx->conn_args.sock = -1;
683 tls_retry_connection:
684 /* Set the address state so that errors are recorded in it */
686 addr->transport_return = PENDING_DEFER;
687 ob->connect_timeout = callout_connect;
688 ob->command_timeout = callout;
690 /* Get the channel set up ready for a message (MAIL FROM being the next
691 SMTP command to send. If we tried TLS but it failed, try again without
694 yield = smtp_setup_conn(sx, FALSE);
697 && addr->basic_errno == ERRNO_TLSFAILURE
698 && ob->tls_tempfail_tryclear
699 && verify_check_given_host(CUSS &ob->hosts_require_tls, host) != OK
702 log_write(0, LOG_MAIN,
703 "%s: callout unencrypted to %s [%s] (not in hosts_require_tls)",
704 addr->message, host->name, host->address);
705 addr->transport_return = PENDING_DEFER;
706 yield = smtp_setup_conn(sx, TRUE);
711 errno = addr->basic_errno;
712 transport_name = NULL;
713 deliver_host = deliver_host_address = NULL;
714 deliver_domain = save_deliver_domain;
716 /* Failure to accept HELO is cached; this blocks the whole domain for all
717 senders. I/O errors and defer responses are not cached. */
719 if (yield == FAIL && (errno == 0 || errno == ERRNO_SMTPCLOSED))
721 setflag(addr, af_verify_nsfail);
722 new_domain_record.result = ccache_reject;
730 /* If we needed to authenticate, smtp_setup_conn() did that. Copy
731 the AUTH info for logging */
733 addr->authenticator = client_authenticator;
734 addr->auth_id = client_authenticated_id;
736 sx->from_addr = from_address;
737 sx->first_addr = sx->sync_addr = addr;
738 sx->ok = FALSE; /*XXX these 3 last might not be needed for verify? */
739 sx->send_rset = TRUE;
740 sx->completed_addr = FALSE;
742 new_domain_record.result = old_domain_cache_result == ccache_reject_mfnull
743 ? ccache_reject_mfnull : ccache_accept;
745 /* Do the random local part check first. Temporarily replace the recipient
746 with the "random" value */
748 if (random_local_part)
750 uschar * main_address = addr->address;
751 const uschar * rcpt_domain = addr->domain;
754 uschar * errstr = NULL;
755 if ( testflag(addr, af_utf8_downcvt)
756 && (rcpt_domain = string_domain_utf8_to_alabel(rcpt_domain,
760 addr->message = errstr;
761 errno = ERRNO_EXPANDFAIL;
762 setflag(addr, af_verify_nsfail);
764 rcpt_domain = US""; /*XXX errorhandling! */
768 /* This would be ok for 1st rcpt of a cutthrough (the case handled here;
769 subsequents are done in cutthrough_multi()), but no way to
770 handle a subsequent because of the RSET vaporising the MAIL FROM.
771 So refuse to support any. Most cutthrough use will not involve
772 random_local_part, so no loss. */
773 cancel_cutthrough_connection(TRUE, US"random-recipient");
775 addr->address = string_sprintf("%s@%.1000s",
776 random_local_part, rcpt_domain);
779 /* If accepted, we aren't going to do any further tests below.
780 Otherwise, cache a real negative response, and get back to the right
781 state to send RCPT. Unless there's some problem such as a dropped
782 connection, we expect to succeed, because the commands succeeded above.
783 However, some servers drop the connection after responding to an
784 invalid recipient, so on (any) error we drop and remake the connection.
785 XXX We don't care about that for postmaster_full. Should we?
787 XXX could we add another flag to the context, and have the common
788 code emit the RSET too? Even pipelined after the RCPT...
789 Then the main-verify call could use it if there's to be a subsequent
791 The sync_responses() would need to be taught about it and we'd
792 need another return code filtering out to here.
794 Avoid using a SIZE option on the MAIL for all random-rcpt checks.
797 sx->avoid_option = OPTION_SIZE;
799 /* Remember when we last did a random test */
800 new_domain_record.random_stamp = time(NULL);
802 if (smtp_write_mail_and_rcpt_cmds(sx, &yield) == 0)
803 switch(addr->transport_return)
805 case PENDING_OK: /* random was accepted, unfortunately */
806 new_domain_record.random_result = ccache_accept;
807 yield = OK; /* Only usable verify result we can return */
809 *failure_ptr = US"random";
811 case FAIL: /* rejected: the preferred result */
812 new_domain_record.random_result = ccache_reject;
813 sx->avoid_option = 0;
815 /* Between each check, issue RSET, because some servers accept only
816 one recipient after MAIL FROM:<>.
817 XXX We don't care about that for postmaster_full. Should we? */
820 smtp_write_command(sx, SCMD_FLUSH, "RSET\r\n") >= 0 &&
821 smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2', callout)))
825 debug_printf_indent("problem after random/rset/mfrom; reopen conn\n");
826 random_local_part = NULL;
828 tls_close(sx->cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);
830 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
831 (void)close(sx->cctx.sock);
833 #ifndef DISABLE_EVENT
834 (void) event_raise(addr->transport->event_action,
835 US"tcp:close", NULL, NULL);
837 addr->address = main_address;
838 addr->transport_return = PENDING_DEFER;
839 sx->first_addr = sx->sync_addr = addr;
841 sx->send_rset = TRUE;
842 sx->completed_addr = FALSE;
843 goto tls_retry_connection;
844 case DEFER: /* 4xx response to random */
845 break; /* Just to be clear. ccache_unknown, !done. */
848 /* Re-setup for main verify, or for the error message when failing */
849 addr->address = main_address;
850 addr->transport_return = PENDING_DEFER;
851 sx->first_addr = sx->sync_addr = addr;
853 sx->send_rset = TRUE;
854 sx->completed_addr = FALSE;
859 /* Main verify. For rcpt-verify use SIZE if we know it and we're not cacheing;
860 for sndr-verify never use it. */
864 if (!(options & vopt_is_recipient && options & vopt_callout_no_cache))
865 sx->avoid_option = OPTION_SIZE;
868 switch(smtp_write_mail_and_rcpt_cmds(sx, &yield))
870 case 0: switch(addr->transport_return) /* ok so far */
872 case PENDING_OK: done = TRUE;
873 new_address_record.result = ccache_accept;
875 case FAIL: done = TRUE;
877 *failure_ptr = US"recipient";
878 new_address_record.result = ccache_reject;
884 case -1: /* MAIL response error */
885 *failure_ptr = US"mail";
886 if (errno == 0 && sx->buffer[0] == '5')
888 setflag(addr, af_verify_nsfail);
889 if (from_address[0] == 0)
890 new_domain_record.result = ccache_reject_mfnull;
893 /* non-MAIL read i/o error */
894 /* non-MAIL response timeout */
895 /* internal error; channel still usable */
896 default: break; /* transmit failed */
900 addr->auth_sndr = client_authenticated_sender;
902 deliver_host = deliver_host_address = NULL;
903 deliver_domain = save_deliver_domain;
905 /* Do postmaster check if requested; if a full check is required, we
906 check for RCPT TO:<postmaster> (no domain) in accordance with RFC 821. */
908 if (done && pm_mailfrom)
910 /* Could possibly shift before main verify, just above, and be ok
911 for cutthrough. But no way to handle a subsequent rcpt, so just
913 cancel_cutthrough_connection(TRUE, US"postmaster verify");
914 HDEBUG(D_acl|D_v) debug_printf_indent("Cutthrough cancelled by presence of postmaster verify\n");
916 done = smtp_write_command(sx, SCMD_FLUSH, "RSET\r\n") >= 0
917 && smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2', callout);
921 uschar * main_address = addr->address;
923 /*XXX oops, affixes */
924 addr->address = string_sprintf("postmaster@%.1000s", addr->domain);
925 addr->transport_return = PENDING_DEFER;
927 sx->from_addr = pm_mailfrom;
928 sx->first_addr = sx->sync_addr = addr;
930 sx->send_rset = TRUE;
931 sx->completed_addr = FALSE;
932 sx->avoid_option = OPTION_SIZE;
934 if( smtp_write_mail_and_rcpt_cmds(sx, &yield) == 0
935 && addr->transport_return == PENDING_OK
939 done = (options & vopt_callout_fullpm) != 0
940 && smtp_write_command(sx, SCMD_FLUSH,
941 "RCPT TO:<postmaster>\r\n") >= 0
942 && smtp_read_response(sx, sx->buffer,
943 sizeof(sx->buffer), '2', callout);
945 /* Sort out the cache record */
947 new_domain_record.postmaster_stamp = time(NULL);
950 new_domain_record.postmaster_result = ccache_accept;
951 else if (errno == 0 && sx->buffer[0] == '5')
953 *failure_ptr = US"postmaster";
954 setflag(addr, af_verify_pmfail);
955 new_domain_record.postmaster_result = ccache_reject;
958 addr->address = main_address;
961 /* For any failure of the main check, other than a negative response, we just
962 close the connection and carry on. We can identify a negative response by the
963 fact that errno is zero. For I/O errors it will be non-zero
965 Set up different error texts for logging and for sending back to the caller
966 as an SMTP response. Log in all cases, using a one-line format. For sender
967 callouts, give a full response to the caller, but for recipient callouts,
968 don't give the IP address because this may be an internal host whose identity
969 is not to be widely broadcast. */
975 HDEBUG(D_verify) debug_printf("SMTP timeout\n");
976 sx->send_quit = FALSE;
982 extern int acl_where; /* src/acl.c */
984 addr->message = US"response to \"EHLO\" did not include SMTPUTF8";
985 addr->user_message = acl_where == ACL_WHERE_RCPT
986 ? US"533 no support for internationalised mailbox name"
987 : US"550 mailbox unavailable";
994 sx->send_quit = FALSE;
998 if (*sx->buffer == 0) Ustrcpy(sx->buffer, US"connection dropped");
1000 /*XXX test here is ugly; seem to have a split of responsibility for
1001 building this message. Need to rationalise. Where is it done
1002 before here, and when not?
1003 Not == 5xx resp to MAIL on main-verify
1005 if (!addr->message) addr->message =
1006 string_sprintf("response to \"%s\" was: %s",
1007 big_buffer, string_printing(sx->buffer));
1009 /* RFC 5321 section 4.2: the text portion of the response may have only
1010 HT, SP, Printable US-ASCII. Deal with awkward chars by cutting the
1011 received message off before passing it onward. Newlines are ok; they
1012 just become a multiline response (but wrapped in the error code we
1015 for (uschar * s = sx->buffer;
1016 *s && s < sx->buffer + sizeof(sx->buffer);
1020 if (c != '\t' && c != '\n' && (c < ' ' || c > '~'))
1022 if (s - sx->buffer < sizeof(sx->buffer) - 12)
1023 memcpy(s, "(truncated)", 12);
1029 addr->user_message = options & vopt_is_recipient
1030 ? string_sprintf("Callout verification failed:\n%s", sx->buffer)
1031 : string_sprintf("Called: %s\nSent: %s\nResponse: %s",
1032 host->address, big_buffer, sx->buffer);
1034 /* Hard rejection ends the process */
1036 if (sx->buffer[0] == '5') /* Address rejected */
1044 /* End the SMTP conversation and close the connection. */
1046 /* Cutthrough - on a successful connect and recipient-verify with
1047 use-sender and we are 1st rcpt and have no cutthrough conn so far
1048 here is where we want to leave the conn open. Ditto for a lazy-close
1051 if (cutthrough.delivery)
1053 if (addr->transport->filter_command)
1055 cutthrough.delivery= FALSE;
1056 HDEBUG(D_acl|D_v) debug_printf("Cutthrough cancelled by presence of transport filter\n");
1058 #ifndef DISABLE_DKIM
1059 /* DKIM signing needs to add a header after seeing the whole body, so we cannot just copy
1060 body bytes to the outbound as they are received, which is the intent of cutthrough. */
1061 if (ob->dkim.dkim_domain)
1063 cutthrough.delivery= FALSE;
1064 HDEBUG(D_acl|D_v) debug_printf("Cutthrough cancelled by presence of DKIM signing\n");
1067 #ifdef EXPERIMENTAL_ARC
1070 cutthrough.delivery= FALSE;
1071 HDEBUG(D_acl|D_v) debug_printf("Cutthrough cancelled by presence of ARC signing\n");
1076 if ( (cutthrough.delivery || options & vopt_callout_hold)
1080 && (options & (vopt_callout_recipsender|vopt_callout_recippmaster|vopt_success_on_redirect))
1081 == vopt_callout_recipsender
1082 && !random_local_part
1084 && cutthrough.cctx.sock < 0
1088 HDEBUG(D_acl|D_v) debug_printf_indent("holding verify callout open for %s\n",
1090 ? "cutthrough delivery" : "potential further verifies and delivery");
1092 cutthrough.callout_hold_only = !cutthrough.delivery;
1093 cutthrough.is_tls = tls_out.active.sock >= 0;
1094 /* We assume no buffer in use in the outblock */
1095 cutthrough.cctx = sx->cctx;
1096 cutthrough.nrcpt = 1;
1097 cutthrough.transport = addr->transport->name;
1098 cutthrough.interface = interface;
1099 cutthrough.snd_port = sending_port;
1100 cutthrough.peer_options = smtp_peer_options;
1101 cutthrough.host = *host;
1103 int oldpool = store_pool;
1104 store_pool = POOL_PERM;
1105 cutthrough.snd_ip = string_copy(sending_ip_address);
1106 cutthrough.host.name = string_copy(host->name);
1107 cutthrough.host.address = string_copy(host->address);
1108 store_pool = oldpool;
1111 /* Save the address_item and parent chain for later logging */
1112 cutthrough.addr = *addr;
1113 cutthrough.addr.next = NULL;
1114 cutthrough.addr.host_used = &cutthrough.host;
1115 for (address_item * caddr = &cutthrough.addr, * parent = addr->parent;
1117 caddr = caddr->parent, parent = parent->parent)
1118 *(caddr->parent = store_get(sizeof(address_item), GET_UNTAINTED)) = *parent;
1120 ctctx.outblock.buffer = ctbuffer;
1121 ctctx.outblock.buffersize = sizeof(ctbuffer);
1122 ctctx.outblock.ptr = ctbuffer;
1123 /* ctctx.outblock.cmd_count = 0; ctctx.outblock.authenticating = FALSE; */
1124 ctctx.outblock.cctx = &cutthrough.cctx;
1128 /* Ensure no cutthrough on multiple verifies that were incompatible */
1129 if (options & vopt_callout_recipsender)
1130 cancel_cutthrough_connection(TRUE, US"not usable for cutthrough");
1132 if (smtp_write_command(sx, SCMD_FLUSH, "QUIT\r\n") != -1)
1133 /* Wait a short time for response, and discard it */
1134 smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2', 1);
1136 if (sx->cctx.sock >= 0)
1139 if (sx->cctx.tls_ctx)
1141 tls_close(sx->cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);
1142 sx->cctx.tls_ctx = NULL;
1145 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
1146 (void)close(sx->cctx.sock);
1148 smtp_debug_cmd_report();
1149 #ifndef DISABLE_EVENT
1150 (void) event_raise(addr->transport->event_action, US"tcp:close", NULL, NULL);
1155 if (!done || yield != OK)
1156 addr->message = string_sprintf("%s [%s] : %s", host->name, host->address,
1158 } /* Loop through all hosts, while !done */
1161 /* If we get here with done == TRUE, a successful callout happened, and yield
1162 will be set OK or FAIL according to the response to the RCPT command.
1163 Otherwise, we looped through the hosts but couldn't complete the business.
1164 However, there may be domain-specific information to cache in both cases. */
1166 if (!(options & vopt_callout_no_cache))
1167 cache_callout_write(&new_domain_record, addr->domain,
1168 done, &new_address_record, address_key);
1170 /* Failure to connect to any host, or any response other than 2xx or 5xx is a
1171 temporary error. If there was only one host, and a response was received, leave
1172 it alone if supplying details. Otherwise, give a generic response. */
1176 uschar * dullmsg = string_sprintf("Could not complete %s verify callout",
1177 options & vopt_is_recipient ? "recipient" : "sender");
1180 addr->message = host_list->next || !addr->message
1181 ? dullmsg : string_sprintf("%s: %s", dullmsg, addr->message);
1183 addr->user_message = smtp_return_error_details
1184 ? string_sprintf("%s for <%s>.\n"
1185 "The mail server(s) for the domain may be temporarily unreachable, or\n"
1186 "they may be permanently unreachable from this server. In the latter case,\n%s",
1187 dullmsg, addr->address,
1188 options & vopt_is_recipient
1189 ? "the address will never be accepted."
1190 : "you need to change the address or create an MX record for its domain\n"
1191 "if it is supposed to be generally accessible from the Internet.\n"
1192 "Talk to your mail administrator for details.")
1195 /* Force a specific error code */
1197 addr->basic_errno = ERRNO_CALLOUTDEFER;
1200 /* Come here from within the cache-reading code on fast-track exit. */
1203 tls_modify_variables(&tls_in); /* return variables to inbound values */
1209 /* Called after recipient-acl to get a cutthrough connection open when
1210 one was requested and a recipient-verify wasn't subsequently done.
1213 open_cutthrough_connection(address_item * addr)
1218 /* Use a recipient-verify-callout to set up the cutthrough connection. */
1219 /* We must use a copy of the address for verification, because it might
1223 HDEBUG(D_acl) debug_printf_indent("----------- %s cutthrough setup ------------\n",
1224 rcpt_count > 1 ? "more" : "start");
1225 rc = verify_address(&addr2, NULL,
1226 vopt_is_recipient | vopt_callout_recipsender | vopt_callout_no_cache,
1227 CUTTHROUGH_CMD_TIMEOUT, -1, -1,
1229 addr->message = addr2.message;
1230 addr->user_message = addr2.user_message;
1231 HDEBUG(D_acl) debug_printf_indent("----------- end cutthrough setup ------------\n");
1237 /* Send given number of bytes from the buffer */
1239 cutthrough_send(int n)
1241 if(cutthrough.cctx.sock < 0)
1247 ? tls_write(cutthrough.cctx.tls_ctx, ctctx.outblock.buffer, n, FALSE)
1250 send(cutthrough.cctx.sock, ctctx.outblock.buffer, n, 0) > 0
1253 transport_count += n;
1254 ctctx.outblock.ptr= ctctx.outblock.buffer;
1258 HDEBUG(D_transport|D_acl) debug_printf_indent("cutthrough_send failed: %s\n", strerror(errno));
1265 _cutthrough_puts(uschar * cp, int n)
1269 if(ctctx.outblock.ptr >= ctctx.outblock.buffer+ctctx.outblock.buffersize)
1270 if(!cutthrough_send(ctctx.outblock.buffersize))
1273 *ctctx.outblock.ptr++ = *cp++;
1278 /* Buffered output of counted data block. Return boolean success */
1280 cutthrough_puts(uschar * cp, int n)
1282 if (cutthrough.cctx.sock < 0) return TRUE;
1283 if (_cutthrough_puts(cp, n)) return TRUE;
1284 cancel_cutthrough_connection(TRUE, US"transmit failed");
1289 cutthrough_data_puts(uschar * cp, int n)
1291 if (cutthrough.delivery) (void) cutthrough_puts(cp, n);
1297 _cutthrough_flush_send(void)
1299 int n = ctctx.outblock.ptr - ctctx.outblock.buffer;
1302 if(!cutthrough_send(n))
1308 /* Send out any bufferred output. Return boolean success. */
1310 cutthrough_flush_send(void)
1312 if (_cutthrough_flush_send()) return TRUE;
1313 cancel_cutthrough_connection(TRUE, US"transmit failed");
1319 cutthrough_put_nl(void)
1321 return cutthrough_puts(US"\r\n", 2);
1326 cutthrough_data_put_nl(void)
1328 cutthrough_data_puts(US"\r\n", 2);
1332 /* Get and check response from cutthrough target.
1337 - cutthrough conn close
1340 cutthrough_response(client_conn_ctx * cctx, char expect, uschar ** copy, int timeout)
1342 smtp_context sx = {0};
1343 uschar inbuffer[4096];
1344 uschar responsebuffer[4096];
1346 sx.inblock.buffer = inbuffer;
1347 sx.inblock.buffersize = sizeof(inbuffer);
1348 sx.inblock.ptr = inbuffer;
1349 sx.inblock.ptrend = inbuffer;
1350 sx.inblock.cctx = cctx;
1351 if(!smtp_read_response(&sx, responsebuffer, sizeof(responsebuffer), expect, timeout))
1352 cancel_cutthrough_connection(TRUE, US"unexpected response to smtp command");
1357 *copy = cp = string_copy(responsebuffer);
1358 /* Trim the trailing end of line */
1359 cp += Ustrlen(responsebuffer);
1360 if(cp > *copy && cp[-1] == '\n') *--cp = '\0';
1361 if(cp > *copy && cp[-1] == '\r') *--cp = '\0';
1364 return responsebuffer[0];
1368 /* Negotiate dataphase with the cutthrough target, returning success boolean */
1370 cutthrough_predata(void)
1372 if(cutthrough.cctx.sock < 0 || cutthrough.callout_hold_only)
1375 smtp_debug_cmd(US"DATA", 0);
1376 cutthrough_puts(US"DATA\r\n", 6);
1377 cutthrough_flush_send();
1379 /* Assume nothing buffered. If it was it gets ignored. */
1380 return cutthrough_response(&cutthrough.cctx, '3', NULL, CUTTHROUGH_DATA_TIMEOUT) == '3';
1384 /* tctx arg only to match write_chunk() */
1386 cutthrough_write_chunk(transport_ctx * tctx, uschar * s, int len)
1389 while(s && (s2 = Ustrchr(s, '\n')))
1391 if(!cutthrough_puts(s, s2-s) || !cutthrough_put_nl())
1399 /* Buffered send of headers. Return success boolean. */
1400 /* Expands newlines to wire format (CR,NL). */
1401 /* Also sends header-terminating blank line. */
1403 cutthrough_headers_send(void)
1407 if(cutthrough.cctx.sock < 0 || cutthrough.callout_hold_only)
1410 /* We share a routine with the mainline transport to handle header add/remove/rewrites,
1411 but having a separate buffered-output function (for now)
1413 HDEBUG(D_acl) debug_printf_indent("----------- start cutthrough headers send -----------\n");
1415 tctx.u.fd = cutthrough.cctx.sock;
1416 tctx.tblock = cutthrough.addr.transport;
1417 tctx.addr = &cutthrough.addr;
1418 tctx.check_string = US".";
1419 tctx.escape_string = US"..";
1420 /*XXX check under spool_files_wireformat. Might be irrelevant */
1421 tctx.options = topt_use_crlf;
1423 if (!transport_headers_send(&tctx, &cutthrough_write_chunk))
1426 HDEBUG(D_acl) debug_printf_indent("----------- done cutthrough headers send ------------\n");
1432 close_cutthrough_connection(const uschar * why)
1434 int fd = cutthrough.cctx.sock;
1437 /* We could be sending this after a bunch of data, but that is ok as
1438 the only way to cancel the transfer in dataphase is to drop the tcp
1439 conn before the final dot.
1441 client_conn_ctx tmp_ctx = cutthrough.cctx;
1442 ctctx.outblock.ptr = ctbuffer;
1443 smtp_debug_cmd(US"QUIT", 0);
1444 _cutthrough_puts(US"QUIT\r\n", 6); /* avoid recursion */
1445 _cutthrough_flush_send();
1446 cutthrough.cctx.sock = -1; /* avoid recursion via read timeout */
1447 cutthrough.nrcpt = 0; /* permit re-cutthrough on subsequent message */
1449 /* Wait a short time for response, and discard it */
1450 cutthrough_response(&tmp_ctx, '2', NULL, 1);
1453 if (cutthrough.is_tls)
1455 tls_close(cutthrough.cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);
1456 cutthrough.cctx.tls_ctx = NULL;
1457 cutthrough.is_tls = FALSE;
1460 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
1462 smtp_debug_cmd_report();
1463 HDEBUG(D_acl) debug_printf_indent("----------- cutthrough shutdown (%s) ------------\n", why);
1465 ctctx.outblock.ptr = ctbuffer;
1469 cancel_cutthrough_connection(BOOL close_noncutthrough_verifies, const uschar * why)
1471 if (cutthrough.delivery || close_noncutthrough_verifies)
1472 close_cutthrough_connection(why);
1473 cutthrough.delivery = cutthrough.callout_hold_only = FALSE;
1478 release_cutthrough_connection(const uschar * why)
1480 if (cutthrough.cctx.sock < 0) return;
1481 HDEBUG(D_acl) debug_printf_indent("release cutthrough conn: %s\n", why);
1482 cutthrough.cctx.sock = -1;
1483 cutthrough.cctx.tls_ctx = NULL;
1484 cutthrough.delivery = cutthrough.callout_hold_only = FALSE;
1490 /* Have senders final-dot. Send one to cutthrough target, and grab the response.
1491 Log an OK response as a transmission.
1492 Close the connection.
1493 Return smtp response-class digit.
1496 cutthrough_finaldot(void)
1499 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP>> .\n");
1501 /* Assume data finshed with new-line */
1502 if( !cutthrough_puts(US".", 1)
1503 || !cutthrough_put_nl()
1504 || !cutthrough_flush_send()
1506 return cutthrough.addr.message;
1508 res = cutthrough_response(&cutthrough.cctx, '2', &cutthrough.addr.message,
1509 CUTTHROUGH_DATA_TIMEOUT);
1510 for (address_item * addr = &cutthrough.addr; addr; addr = addr->next)
1512 addr->message = cutthrough.addr.message;
1516 delivery_log(LOG_MAIN, addr, (int)'>', NULL);
1517 close_cutthrough_connection(US"delivered");
1521 delivery_log(LOG_MAIN, addr, 0,
1522 US"tmp-reject from cutthrough after DATA:");
1526 delivery_log(LOG_MAIN|LOG_REJECT, addr, 0,
1527 US"rejected after DATA:");
1534 return cutthrough.addr.message;
1539 /*************************************************
1540 * Copy error to toplevel address *
1541 *************************************************/
1543 /* This function is used when a verify fails or defers, to ensure that the
1544 failure or defer information is in the original toplevel address. This applies
1545 when an address is redirected to a single new address, and the failure or
1546 deferral happens to the child address.
1549 vaddr the verify address item
1550 addr the final address item
1553 Returns: the value of YIELD
1557 copy_error(address_item *vaddr, address_item *addr, int yield)
1561 vaddr->message = addr->message;
1562 vaddr->user_message = addr->user_message;
1563 vaddr->basic_errno = addr->basic_errno;
1564 vaddr->more_errno = addr->more_errno;
1565 vaddr->prop.address_data = addr->prop.address_data;
1566 vaddr->prop.variables = NULL;
1567 tree_dup((tree_node **)&vaddr->prop.variables, addr->prop.variables);
1568 copyflag(vaddr, addr, af_pass_message);
1576 /**************************************************
1577 * printf that automatically handles TLS if needed *
1578 ***************************************************/
1580 /* This function is used by verify_address() as a substitute for all fprintf()
1581 calls; a direct fprintf() will not produce output in a TLS SMTP session, such
1582 as a response to an EXPN command. smtp_in.c makes smtp_printf available but
1583 that assumes that we always use the smtp_out FILE* when not using TLS or the
1584 ssl buffer when we are. Instead we take a FILE* parameter and check to see if
1585 that is smtp_out; if so, smtp_printf() with TLS support, otherwise regular
1589 f the candidate FILE* to write to
1590 format format string
1591 ... optional arguments
1597 static void PRINTF_FUNCTION(2,3)
1598 respond_printf(FILE *f, const char *format, ...)
1602 va_start(ap, format);
1603 if (smtp_out && (f == smtp_out))
1604 smtp_vprintf(format, FALSE, ap);
1606 vfprintf(f, format, ap);
1612 /*************************************************
1613 * Verify an email address *
1614 *************************************************/
1616 /* This function is used both for verification (-bv and at other times) and
1617 address testing (-bt), which is indicated by address_test_mode being set.
1620 vaddr contains the address to verify; the next field in this block
1622 fp if not NULL, write the result to this file
1623 options various option bits:
1624 vopt_fake_sender => this sender verify is not for the real
1625 sender (it was verify=sender=xxxx or an address from a
1626 header line) - rewriting must not change sender_address
1627 vopt_is_recipient => this is a recipient address, otherwise
1628 it's a sender address - this affects qualification and
1629 rewriting and messages from callouts
1630 vopt_qualify => qualify an unqualified address; else error
1631 vopt_expn => called from SMTP EXPN command
1632 vopt_success_on_redirect => when a new address is generated
1633 the verification instantly succeeds
1635 These ones are used by do_callout() -- the options variable
1638 vopt_callout_fullpm => if postmaster check, do full one
1639 vopt_callout_no_cache => don't use callout cache
1640 vopt_callout_random => do the "random" thing
1641 vopt_callout_recipsender => use real sender for recipient
1642 vopt_callout_recippmaster => use postmaster for recipient
1644 callout if > 0, specifies that callout is required, and gives timeout
1645 for individual commands
1646 callout_overall if > 0, gives overall timeout for the callout function;
1647 if < 0, a default is used (see do_callout())
1648 callout_connect the connection timeout for callouts
1649 se_mailfrom when callout is requested to verify a sender, use this
1650 in MAIL FROM; NULL => ""
1651 pm_mailfrom when callout is requested, if non-NULL, do the postmaster
1652 thing and use this as the sender address (may be "")
1654 routed if not NULL, set TRUE if routing succeeded, so we can
1655 distinguish between routing failed and callout failed
1657 Returns: OK address verified
1658 FAIL address failed to verify
1659 DEFER can't tell at present
1663 verify_address(address_item * vaddr, FILE * fp, int options, int callout,
1664 int callout_overall, int callout_connect, uschar * se_mailfrom,
1665 uschar *pm_mailfrom, BOOL *routed)
1668 BOOL full_info = fp ? debug_selector != 0 : FALSE;
1669 BOOL expn = (options & vopt_expn) != 0;
1670 BOOL success_on_redirect = (options & vopt_success_on_redirect) != 0;
1673 int verify_type = expn ? v_expn :
1674 f.address_test_mode ? v_none :
1675 options & vopt_is_recipient ? v_recipient : v_sender;
1676 address_item *addr_list;
1677 address_item *addr_new = NULL;
1678 address_item *addr_remote = NULL;
1679 address_item *addr_local = NULL;
1680 address_item *addr_succeed = NULL;
1681 uschar **failure_ptr = options & vopt_is_recipient
1682 ? &recipient_verify_failure : &sender_verify_failure;
1683 uschar *ko_prefix, *cr;
1684 uschar *address = vaddr->address;
1685 uschar *save_sender;
1686 uschar null_sender[] = { 0 }; /* Ensure writeable memory */
1688 /* Clear, just in case */
1690 *failure_ptr = NULL;
1692 /* Set up a prefix and suffix for error message which allow us to use the same
1693 output statements both in EXPN mode (where an SMTP response is needed) and when
1694 debugging with an output file. */
1698 ko_prefix = US"553 ";
1701 else ko_prefix = cr = US"";
1703 /* Add qualify domain if permitted; otherwise an unqualified address fails. */
1705 if (parse_find_at(address) == NULL)
1707 if (!(options & vopt_qualify))
1710 respond_printf(fp, "%sA domain is required for \"%s\"%s\n",
1711 ko_prefix, address, cr);
1712 *failure_ptr = US"qualify";
1715 /* deconst ok as address was not const */
1716 address = US rewrite_address_qualify(address, options & vopt_is_recipient);
1721 debug_printf(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
1722 debug_printf("%s %s\n", f.address_test_mode? "Testing" : "Verifying", address);
1725 /* Rewrite and report on it. Clear the domain and local part caches - these
1726 may have been set by domains and local part tests during an ACL. */
1728 if (global_rewrite_rules)
1730 uschar *old = address;
1731 /* deconst ok as address was not const */
1732 address = US rewrite_address(address, options & vopt_is_recipient, FALSE,
1733 global_rewrite_rules, rewrite_existflags);
1736 for (int i = 0; i < (MAX_NAMED_LIST * 2)/32; i++) vaddr->localpart_cache[i] = 0;
1737 for (int i = 0; i < (MAX_NAMED_LIST * 2)/32; i++) vaddr->domain_cache[i] = 0;
1738 if (fp && !expn) fprintf(fp, "Address rewritten as: %s\n", address);
1742 /* If this is the real sender address, we must update sender_address at
1743 this point, because it may be referred to in the routers. */
1745 if (!(options & (vopt_fake_sender|vopt_is_recipient)))
1746 sender_address = address;
1748 /* If the address was rewritten to <> no verification can be done, and we have
1749 to return OK. This rewriting is permitted only for sender addresses; for other
1750 addresses, such rewriting fails. */
1752 if (!address[0]) return OK;
1754 /* Flip the legacy TLS-related variables over to the outbound set in case
1755 they're used in the context of a transport used by verification. Reset them
1756 at exit from this routine (so no returns allowed from here on). */
1758 tls_modify_variables(&tls_out);
1760 /* Save a copy of the sender address for re-instating if we change it to <>
1761 while verifying a sender address (a nice bit of self-reference there). */
1763 save_sender = sender_address;
1765 /* Observability variable for router/transport use */
1767 verify_mode = options & vopt_is_recipient ? US"R" : US"S";
1769 /* Update the address structure with the possibly qualified and rewritten
1770 address. Set it up as the starting address on the chain of new addresses. */
1772 vaddr->address = address;
1775 /* We need a loop, because an address can generate new addresses. We must also
1776 cope with generated pipes and files at the top level. (See also the code and
1777 comment in deliver.c.) However, it is usually the case that the router for
1778 user's .forward files has its verify flag turned off.
1780 If an address generates more than one child, the loop is used only when
1781 full_info is set, and this can only be set locally. Remote enquiries just get
1782 information about the top level address, not anything that it generated. */
1787 address_item *addr = addr_new;
1789 addr_new = addr->next;
1794 debug_printf(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
1795 debug_printf("Considering %s\n", addr->address);
1798 /* Handle generated pipe, file or reply addresses. We don't get these
1799 when handling EXPN, as it does only one level of expansion. */
1801 if (testflag(addr, af_pfr))
1808 if (addr->address[0] == '>')
1810 allow = testflag(addr, af_allow_reply);
1811 fprintf(fp, "%s -> mail %s", addr->parent->address, addr->address + 1);
1815 allow = addr->address[0] == '|'
1816 ? testflag(addr, af_allow_pipe) : testflag(addr, af_allow_file);
1817 fprintf(fp, "%s -> %s", addr->parent->address, addr->address);
1820 if (addr->basic_errno == ERRNO_BADTRANSPORT)
1821 fprintf(fp, "\n*** Error in setting up pipe, file, or autoreply:\n"
1822 "%s\n", addr->message);
1824 fprintf(fp, "\n transport = %s\n", addr->transport->name);
1826 fprintf(fp, " *** forbidden ***\n");
1831 /* Just in case some router parameter refers to it. */
1833 return_path = addr->prop.errors_address
1834 ? addr->prop.errors_address : sender_address;
1836 /* Split the address into domain and local part, handling the %-hack if
1837 necessary, and then route it. While routing a sender address, set
1838 $sender_address to <> because that is what it will be if we were trying to
1839 send a bounce to the sender. */
1841 if (routed) *routed = FALSE;
1842 if ((rc = deliver_split_address(addr)) == OK)
1844 if (!(options & vopt_is_recipient)) sender_address = null_sender;
1845 rc = route_address(addr, &addr_local, &addr_remote, &addr_new,
1846 &addr_succeed, verify_type);
1847 sender_address = save_sender; /* Put back the real sender */
1850 /* If routing an address succeeded, set the flag that remembers, for use when
1851 an ACL cached a sender verify (in case a callout fails). Then if routing set
1852 up a list of hosts or the transport has a host list, and the callout option
1853 is set, and we aren't in a host checking run, do the callout verification,
1854 and set another flag that notes that a callout happened. */
1858 BOOL local_verify = FALSE;
1860 if (routed) *routed = TRUE;
1863 transport_instance * tp;
1864 host_item * host_list = addr->host_list;
1866 /* Make up some data for use in the case where there is no remote
1869 transport_feedback tf = {
1870 .interface = NULL, /* interface (=> any) */
1872 .protocol = US"smtp",
1874 .helo_data = US"$smtp_active_hostname",
1875 .hosts_override = FALSE,
1876 .hosts_randomize = FALSE,
1877 .gethostbyname = FALSE,
1878 .qualify_single = TRUE,
1879 .search_parents = FALSE
1882 /* If verification yielded a remote transport, we want to use that
1883 transport's options, so as to mimic what would happen if we were really
1884 sending a message to this address. */
1886 if ((tp = addr->transport))
1887 if (!tp->info->local)
1889 (void)(tp->setup)(tp, addr, &tf, 0, 0, NULL);
1891 /* If the transport has hosts and the router does not, or if the
1892 transport is configured to override the router's hosts, we must build a
1893 host list of the transport's hosts, and find the IP addresses */
1895 if (tf.hosts && (!host_list || tf.hosts_override))
1898 const uschar *save_deliver_domain = deliver_domain;
1899 uschar *save_deliver_localpart = deliver_localpart;
1901 host_list = NULL; /* Ignore the router's hosts */
1903 deliver_domain = addr->domain;
1904 deliver_localpart = addr->local_part;
1905 s = expand_string(tf.hosts);
1906 deliver_domain = save_deliver_domain;
1907 deliver_localpart = save_deliver_localpart;
1911 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand list of hosts "
1912 "\"%s\" in %s transport for callout: %s", tf.hosts,
1913 tp->name, expand_string_message);
1918 host_build_hostlist(&host_list, s, tf.hosts_randomize);
1920 /* Just ignore failures to find a host address. If we don't manage
1921 to find any addresses, the callout will defer. Note that more than
1922 one address may be found for a single host, which will result in
1923 additional host items being inserted into the chain. Hence we must
1924 save the next host first. */
1926 flags = HOST_FIND_BY_A | HOST_FIND_BY_AAAA;
1927 if (tf.qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
1928 if (tf.search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
1930 for (host_item * host = host_list, * nexthost; host; host = nexthost)
1932 nexthost = host->next;
1933 if (tf.gethostbyname ||
1934 string_is_ip_address(host->name, NULL) != 0)
1935 (void)host_find_byname(host, NULL, flags, NULL, TRUE);
1938 const dnssec_domains * dsp = NULL;
1939 if (Ustrcmp(tp->driver_name, "smtp") == 0)
1941 smtp_transport_options_block * ob =
1942 (smtp_transport_options_block *) tp->options_block;
1946 (void) host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
1953 else if ( options & vopt_quota
1954 && Ustrcmp(tp->driver_name, "appendfile") == 0)
1955 local_verify = TRUE;
1957 /* Can only do a callout if we have at least one host! If the callout
1958 fails, it will have set ${sender,recipient}_verify_failure. */
1962 HDEBUG(D_verify) debug_printf("Attempting full verification using callout\n");
1963 if (host_checking && !f.host_checking_callout)
1966 debug_printf("... callout omitted by default when host testing\n"
1967 "(Use -bhc if you want the callouts to happen.)\n");
1972 deliver_set_expansions(addr);
1974 rc = do_callout(addr, host_list, &tf, callout, callout_overall,
1975 callout_connect, options, se_mailfrom, pm_mailfrom);
1977 deliver_set_expansions(NULL);
1979 if ( options & vopt_is_recipient
1981 /* set to "random", with OK, for an accepted random */
1982 && !recipient_verify_failure
1984 callout_verified_rcpt(addr);
1987 else if (local_verify)
1989 HDEBUG(D_verify) debug_printf("Attempting quota verification\n");
1991 deliver_set_expansions(addr);
1992 deliver_local(addr, TRUE);
1993 rc = addr->transport_return;
1996 HDEBUG(D_verify) debug_printf("Cannot do callout: neither router nor "
1997 "transport provided a host list, or transport is not smtp\n");
2001 /* Otherwise, any failure is a routing failure */
2003 else *failure_ptr = US"route";
2005 /* A router may return REROUTED if it has set up a child address as a result
2006 of a change of domain name (typically from widening). In this case we always
2007 want to continue to verify the new child. */
2009 if (rc == REROUTED) continue;
2011 /* Handle hard failures */
2018 address_item *p = addr->parent;
2020 respond_printf(fp, "%s%s %s", ko_prefix,
2021 full_info ? addr->address : address,
2022 f.address_test_mode ? "is undeliverable" : "failed to verify");
2023 if (!expn && f.admin_user)
2025 if (addr->basic_errno > 0)
2026 respond_printf(fp, ": %s", strerror(addr->basic_errno));
2028 respond_printf(fp, ": %s", addr->message);
2031 /* Show parents iff doing full info */
2033 if (full_info) while (p)
2035 respond_printf(fp, "%s\n <-- %s", cr, p->address);
2038 respond_printf(fp, "%s\n", cr);
2040 cancel_cutthrough_connection(TRUE, US"routing hard fail");
2044 yield = copy_error(vaddr, addr, FAIL);
2052 else if (rc == DEFER)
2057 address_item *p = addr->parent;
2058 respond_printf(fp, "%s%s cannot be resolved at this time", ko_prefix,
2059 full_info? addr->address : address);
2060 if (!expn && f.admin_user)
2062 if (addr->basic_errno > 0)
2063 respond_printf(fp, ": %s", strerror(addr->basic_errno));
2065 respond_printf(fp, ": %s", addr->message);
2066 else if (addr->basic_errno <= 0)
2067 respond_printf(fp, ": unknown error");
2070 /* Show parents iff doing full info */
2072 if (full_info) while (p)
2074 respond_printf(fp, "%s\n <-- %s", cr, p->address);
2077 respond_printf(fp, "%s\n", cr);
2079 cancel_cutthrough_connection(TRUE, US"routing soft fail");
2083 yield = copy_error(vaddr, addr, DEFER);
2086 if (yield == OK) yield = DEFER;
2089 /* If we are handling EXPN, we do not want to continue to route beyond
2090 the top level (whose address is in "address"). */
2094 uschar *ok_prefix = US"250-";
2097 if (!addr_local && !addr_remote)
2098 respond_printf(fp, "250 mail to <%s> is discarded\r\n", address);
2100 respond_printf(fp, "250 <%s>\r\n", address);
2104 address_item *addr2 = addr_new;
2105 addr_new = addr2->next;
2106 if (!addr_new) ok_prefix = US"250 ";
2107 respond_printf(fp, "%s<%s>\r\n", ok_prefix, addr2->address);
2113 /* Successful routing other than EXPN. */
2117 /* Handle successful routing when short info wanted. Otherwise continue for
2118 other (generated) addresses. Short info is the operational case. Full info
2119 can be requested only when debug_selector != 0 and a file is supplied.
2121 There is a conflict between the use of aliasing as an alternate email
2122 address, and as a sort of mailing list. If an alias turns the incoming
2123 address into just one address (e.g. J.Caesar->jc44) you may well want to
2124 carry on verifying the generated address to ensure it is valid when
2125 checking incoming mail. If aliasing generates multiple addresses, you
2126 probably don't want to do this. Exim therefore treats the generation of
2127 just a single new address as a special case, and continues on to verify the
2128 generated address. */
2130 if ( !full_info /* Stop if short info wanted AND */
2131 && ( ( !addr_new /* No new address OR */
2132 || addr_new->next /* More than one new address OR */
2133 || testflag(addr_new, af_pfr) /* New address is pfr */
2136 ( addr_new /* At least one new address AND */
2137 && success_on_redirect /* success_on_redirect is set */
2141 if (fp) fprintf(fp, "%s %s\n",
2142 address, f.address_test_mode ? "is deliverable" : "verified");
2144 /* If we have carried on to verify a child address, we want the value
2145 of $address_data to be that of the child */
2147 vaddr->prop.address_data = addr->prop.address_data;
2148 vaddr->prop.variables = NULL;
2149 tree_dup((tree_node **)&vaddr->prop.variables, addr->prop.variables);
2151 /* If stopped because more than one new address, cannot cutthrough */
2153 if (addr_new && addr_new->next)
2154 cancel_cutthrough_connection(TRUE, US"multiple addresses from routing");
2160 } /* Loop for generated addresses */
2162 /* Display the full results of the successful routing, including any generated
2163 addresses. Control gets here only when full_info is set, which requires fp not
2164 to be NULL, and this occurs only when a top-level verify is called with the
2165 debugging switch on.
2167 If there are no local and no remote addresses, and there were no pipes, files,
2168 or autoreplies, and there were no errors or deferments, the message is to be
2169 discarded, usually because of the use of :blackhole: in an alias file. */
2171 if (allok && !addr_local && !addr_remote)
2173 fprintf(fp, "mail to %s is discarded\n", address);
2177 for (addr_list = addr_local, i = 0; i < 2; addr_list = addr_remote, i++)
2180 address_item *addr = addr_list;
2181 transport_instance * tp = addr->transport;
2183 addr_list = addr->next;
2185 fprintf(fp, "%s", CS addr->address);
2187 /* If the address is a duplicate, show something about it. */
2189 if (!testflag(addr, af_pfr))
2192 if ((tnode = tree_search(tree_duplicates, addr->unique)))
2193 fprintf(fp, " [duplicate, would not be delivered]");
2194 else tree_add_duplicate(addr->unique, addr);
2197 /* Now show its parents */
2199 for (address_item * p = addr->parent; p; p = p->parent)
2200 fprintf(fp, "\n <-- %s", p->address);
2203 /* Show router, and transport */
2205 fprintf(fp, "router = %s, transport = %s\n",
2206 addr->router->name, tp ? tp->name : US"unset");
2208 /* Show any hosts that are set up by a router unless the transport
2209 is going to override them; fiddle a bit to get a nice format. */
2211 if (addr->host_list && tp && !tp->overrides_hosts)
2215 for (host_item * h = addr->host_list; h; h = h->next)
2216 { /* get max lengths of host names, addrs */
2217 int len = Ustrlen(h->name);
2218 if (len > maxlen) maxlen = len;
2219 len = h->address ? Ustrlen(h->address) : 7;
2220 if (len > maxaddlen) maxaddlen = len;
2222 for (host_item * h = addr->host_list; h; h = h->next)
2224 fprintf(fp, " host %-*s ", maxlen, h->name);
2227 fprintf(fp, "[%s%-*c", h->address, maxaddlen+1 - Ustrlen(h->address), ']');
2228 else if (tp->info->local)
2229 fprintf(fp, " %-*s ", maxaddlen, ""); /* Omit [unknown] for local */
2231 fprintf(fp, "[%s%-*c", "unknown", maxaddlen+1 - 7, ']');
2233 if (h->mx >= 0) fprintf(fp, " MX=%d", h->mx);
2234 if (h->port != PORT_NONE) fprintf(fp, " port=%d", h->port);
2235 if (f.running_in_test_harness && h->dnssec == DS_YES) fputs(" AD", fp);
2236 if (h->status == hstatus_unusable) fputs(" ** unusable **", fp);
2242 /* Yield will be DEFER or FAIL if any one address has, only for full_info (which is
2243 the -bv or -bt case). */
2247 tls_modify_variables(&tls_in); /* return variables to inbound values */
2255 /*************************************************
2256 * Check headers for syntax errors *
2257 *************************************************/
2259 /* This function checks those header lines that contain addresses, and verifies
2260 that all the addresses therein are 5322-syntactially correct.
2263 msgptr where to put an error message
2270 verify_check_headers(uschar **msgptr)
2275 for (header_line * h = header_list; h && yield == OK; h = h->next)
2277 if (h->type != htype_from &&
2278 h->type != htype_reply_to &&
2279 h->type != htype_sender &&
2280 h->type != htype_to &&
2281 h->type != htype_cc &&
2282 h->type != htype_bcc)
2285 colon = Ustrchr(h->text, ':');
2287 Uskip_whitespace(&s);
2289 /* Loop for multiple addresses in the header, enabling group syntax. Note
2290 that we have to reset this after the header has been scanned. */
2292 f.parse_allow_group = TRUE;
2296 uschar *ss = parse_find_address_end(s, FALSE);
2297 uschar *recipient, *errmess;
2298 int terminator = *ss;
2299 int start, end, domain;
2301 /* Temporarily terminate the string at this point, and extract the
2302 operative address within, allowing group syntax. */
2305 recipient = parse_extract_address(s,&errmess,&start,&end,&domain,FALSE);
2308 /* Permit an unqualified address only if the message is local, or if the
2309 sending host is configured to be permitted to send them. */
2311 if (recipient && !domain)
2313 if (h->type == htype_from || h->type == htype_sender)
2315 if (!f.allow_unqualified_sender) recipient = NULL;
2319 if (!f.allow_unqualified_recipient) recipient = NULL;
2321 if (!recipient) errmess = US"unqualified address not permitted";
2324 /* It's an error if no address could be extracted, except for the special
2325 case of an empty address. */
2327 if (!recipient && Ustrcmp(errmess, "empty address") != 0)
2329 uschar *verb = US"is";
2334 /* Arrange not to include any white space at the end in the
2335 error message or the header name. */
2337 while (t > s && isspace(t[-1])) t--;
2338 while (tt > h->text && isspace(tt[-1])) tt--;
2340 /* Add the address that failed to the error message, since in a
2341 header with very many addresses it is sometimes hard to spot
2342 which one is at fault. However, limit the amount of address to
2343 quote - cases have been seen where, for example, a missing double
2344 quote in a humungous To: header creates an "address" that is longer
2345 than string_sprintf can handle. */
2354 /* deconst cast ok as we're passing a non-const to string_printing() */
2355 *msgptr = US string_printing(
2356 string_sprintf("%s: failing address in \"%.*s:\" header %s: %.*s",
2357 errmess, (int)(tt - h->text), h->text, verb, len, s));
2360 break; /* Out of address loop */
2363 /* Advance to the next address */
2365 s = ss + (terminator ? 1 : 0);
2366 Uskip_whitespace(&s);
2367 } /* Next address */
2369 f.parse_allow_group = FALSE;
2370 f.parse_found_group = FALSE;
2371 } /* Next header unless yield has been set FALSE */
2377 /*************************************************
2378 * Check header names for 8-bit characters *
2379 *************************************************/
2381 /* This function checks for invalid characters in header names. See
2382 RFC 5322, 2.2. and RFC 6532, 3.
2385 msgptr where to put an error message
2392 verify_check_header_names_ascii(uschar **msgptr)
2396 for (header_line * h = header_list; h; h = h->next)
2398 colon = Ustrchr(h->text, ':');
2399 for(uschar * s = h->text; s < colon; s++)
2400 if ((*s < 33) || (*s > 126))
2402 *msgptr = string_sprintf("Invalid character in header \"%.*s\" found",
2403 (int)(colon - h->text), h->text);
2410 /*************************************************
2411 * Check for blind recipients *
2412 *************************************************/
2414 /* This function checks that every (envelope) recipient is mentioned in either
2415 the To: or Cc: header lines, thus detecting blind carbon copies.
2417 There are two ways of scanning that could be used: either scan the header lines
2418 and tick off the recipients, or scan the recipients and check the header lines.
2419 The original proposed patch did the former, but I have chosen to do the latter,
2420 because (a) it requires no memory and (b) will use fewer resources when there
2421 are many addresses in To: and/or Cc: and only one or two envelope recipients.
2423 Arguments: case_sensitive true if case sensitive matching should be used
2424 Returns: OK if there are no blind recipients
2425 FAIL if there is at least one blind recipient
2429 verify_check_notblind(BOOL case_sensitive)
2431 for (int i = 0; i < recipients_count; i++)
2434 uschar *address = recipients_list[i].address;
2436 for (header_line * h = header_list; !found && h; h = h->next)
2440 if (h->type != htype_to && h->type != htype_cc) continue;
2442 colon = Ustrchr(h->text, ':');
2444 Uskip_whitespace(&s);
2446 /* Loop for multiple addresses in the header, enabling group syntax. Note
2447 that we have to reset this after the header has been scanned. */
2449 f.parse_allow_group = TRUE;
2453 uschar * ss = parse_find_address_end(s, FALSE);
2454 uschar * recipient, * errmess;
2455 int terminator = *ss;
2456 int start, end, domain;
2458 /* Temporarily terminate the string at this point, and extract the
2459 operative address within, allowing group syntax. */
2462 recipient = parse_extract_address(s,&errmess,&start,&end,&domain,FALSE);
2465 /* If we found a valid recipient that has a domain, compare it with the
2466 envelope recipient. Local parts are compared with case-sensitivity
2467 according to the routine arg, domains case-insensitively.
2468 By comparing from the start with length "domain", we include the "@" at
2469 the end, which ensures that we are comparing the whole local part of each
2472 if (recipient && domain != 0)
2473 if ((found = (case_sensitive
2474 ? Ustrncmp(recipient, address, domain) == 0
2475 : strncmpic(recipient, address, domain) == 0)
2476 && strcmpic(recipient + domain, address + domain) == 0))
2479 /* Advance to the next address */
2481 s = ss + (terminator ? 1:0);
2482 Uskip_whitespace(&s);
2483 } /* Next address */
2485 f.parse_allow_group = FALSE;
2486 f.parse_found_group = FALSE;
2487 } /* Next header (if found is false) */
2489 if (!found) return FAIL;
2490 } /* Next recipient */
2497 /*************************************************
2498 * Find if verified sender *
2499 *************************************************/
2501 /* Usually, just a single address is verified as the sender of the message.
2502 However, Exim can be made to verify other addresses as well (often related in
2503 some way), and this is useful in some environments. There may therefore be a
2504 chain of such addresses that have previously been tested. This function finds
2505 whether a given address is on the chain.
2507 Arguments: the address to be verified
2508 Returns: pointer to an address item, or NULL
2512 verify_checked_sender(uschar *sender)
2514 for (address_item * addr = sender_verified_list; addr; addr = addr->next)
2515 if (Ustrcmp(sender, addr->address) == 0) return addr;
2523 /*************************************************
2524 * Get valid header address *
2525 *************************************************/
2527 /* Scan the originator headers of the message, looking for an address that
2528 verifies successfully. RFC 822 says:
2530 o The "Sender" field mailbox should be sent notices of
2531 any problems in transport or delivery of the original
2532 messages. If there is no "Sender" field, then the
2533 "From" field mailbox should be used.
2535 o If the "Reply-To" field exists, then the reply should
2536 go to the addresses indicated in that field and not to
2537 the address(es) indicated in the "From" field.
2539 So we check a Sender field if there is one, else a Reply_to field, else a From
2540 field. As some strange messages may have more than one of these fields,
2541 especially if they are resent- fields, check all of them if there is more than
2545 user_msgptr points to where to put a user error message
2546 log_msgptr points to where to put a log error message
2547 callout timeout for callout check (passed to verify_address())
2548 callout_overall overall callout timeout (ditto)
2549 callout_connect connect callout timeout (ditto)
2550 se_mailfrom mailfrom for verify; NULL => ""
2551 pm_mailfrom sender for pm callout check (passed to verify_address())
2552 options callout options (passed to verify_address())
2553 verrno where to put the address basic_errno
2555 If log_msgptr is set to something without setting user_msgptr, the caller
2556 normally uses log_msgptr for both things.
2558 Returns: result of the verification attempt: OK, FAIL, or DEFER;
2559 FAIL is given if no appropriate headers are found
2563 verify_check_header_address(uschar **user_msgptr, uschar **log_msgptr,
2564 int callout, int callout_overall, int callout_connect, uschar *se_mailfrom,
2565 uschar *pm_mailfrom, int options, int *verrno)
2567 static int header_types[] = { htype_sender, htype_reply_to, htype_from };
2571 for (int i = 0; i < 3 && !done; i++)
2572 for (header_line * h = header_list; h != NULL && !done; h = h->next)
2574 int terminator, new_ok;
2575 uschar *s, *ss, *endname;
2577 if (h->type != header_types[i]) continue;
2578 s = endname = Ustrchr(h->text, ':') + 1;
2580 /* Scan the addresses in the header, enabling group syntax. Note that we
2581 have to reset this after the header has been scanned. */
2583 f.parse_allow_group = TRUE;
2587 address_item *vaddr;
2589 while (isspace(*s) || *s == ',') s++;
2590 if (*s == 0) break; /* End of header */
2592 ss = parse_find_address_end(s, FALSE);
2594 /* The terminator is a comma or end of header, but there may be white
2595 space preceding it (including newline for the last address). Move back
2596 past any white space so we can check against any cached envelope sender
2597 address verifications. */
2599 while (isspace(ss[-1])) ss--;
2603 HDEBUG(D_verify) debug_printf("verifying %.*s header address %s\n",
2604 (int)(endname - h->text), h->text, s);
2606 /* See if we have already verified this address as an envelope sender,
2607 and if so, use the previous answer. */
2609 vaddr = verify_checked_sender(s);
2611 if (vaddr != NULL && /* Previously checked */
2612 (callout <= 0 || /* No callout needed; OR */
2613 vaddr->special_action > 256)) /* Callout was done */
2615 new_ok = vaddr->special_action & 255;
2616 HDEBUG(D_verify) debug_printf("previously checked as envelope sender\n");
2617 *ss = terminator; /* Restore shortened string */
2620 /* Otherwise we run the verification now. We must restore the shortened
2621 string before running the verification, so the headers are correct, in
2622 case there is any rewriting. */
2626 int start, end, domain;
2627 uschar *address = parse_extract_address(s, log_msgptr, &start, &end,
2632 /* If we found an empty address, just carry on with the next one, but
2633 kill the message. */
2635 if (!address && Ustrcmp(*log_msgptr, "empty address") == 0)
2642 /* If verification failed because of a syntax error, fail this
2643 function, and ensure that the failing address gets added to the error
2649 while (ss > s && isspace(ss[-1])) ss--;
2650 *log_msgptr = string_sprintf("syntax error in '%.*s' header when "
2651 "scanning for sender: %s in \"%.*s\"",
2652 (int)(endname - h->text), h->text, *log_msgptr, (int)(ss - s), s);
2658 /* Else go ahead with the sender verification. But it isn't *the*
2659 sender of the message, so set vopt_fake_sender to stop sender_address
2660 being replaced after rewriting or qualification. */
2664 vaddr = deliver_make_addr(address, FALSE);
2665 new_ok = verify_address(vaddr, NULL, options | vopt_fake_sender,
2666 callout, callout_overall, callout_connect, se_mailfrom,
2671 /* We now have the result, either newly found, or cached. If we are
2672 giving out error details, set a specific user error. This means that the
2673 last of these will be returned to the user if all three fail. We do not
2674 set a log message - the generic one below will be used. */
2678 *verrno = vaddr->basic_errno;
2679 if (smtp_return_error_details)
2680 *user_msgptr = string_sprintf("Rejected after DATA: "
2681 "could not verify \"%.*s\" header address\n%s: %s",
2682 (int)(endname - h->text), h->text, vaddr->address, vaddr->message);
2685 /* Success or defer */
2694 if (new_ok == DEFER) yield = DEFER;
2696 /* Move on to any more addresses in the header */
2699 } /* Next address */
2701 f.parse_allow_group = FALSE;
2702 f.parse_found_group = FALSE;
2703 } /* Next header, unless done */
2704 /* Next header type unless done */
2706 if (yield == FAIL && *log_msgptr == NULL)
2707 *log_msgptr = US"there is no valid sender in any header line";
2709 if (yield == DEFER && *log_msgptr == NULL)
2710 *log_msgptr = US"all attempts to verify a sender in a header line deferred";
2718 /*************************************************
2719 * Get RFC 1413 identification *
2720 *************************************************/
2722 /* Attempt to get an id from the sending machine via the RFC 1413 protocol. If
2723 the timeout is set to zero, then the query is not done. There may also be lists
2724 of hosts and nets which are exempt. To guard against malefactors sending
2725 non-printing characters which could, for example, disrupt a message's headers,
2726 make sure the string consists of printing characters only.
2729 port the port to connect to; usually this is IDENT_PORT (113), but when
2730 running in the test harness with -bh a different value is used.
2734 Side effect: any received ident value is put in sender_ident (NULL otherwise)
2738 verify_get_ident(int port)
2740 client_conn_ctx ident_conn_ctx = {0};
2742 int received_sender_port, received_interface_port, n;
2745 uschar buffer[2048];
2747 /* Default is no ident. Check whether we want to do an ident check for this
2750 sender_ident = NULL;
2751 if (rfc1413_query_timeout <= 0 || verify_check_host(&rfc1413_hosts) != OK)
2754 DEBUG(D_ident) debug_printf("doing ident callback\n");
2756 /* Set up a connection to the ident port of the remote host. Bind the local end
2757 to the incoming interface address. If the sender host address is an IPv6
2758 address, the incoming interface address will also be IPv6. */
2760 host_af = Ustrchr(sender_host_address, ':') == NULL ? AF_INET : AF_INET6;
2761 if ((ident_conn_ctx.sock = ip_socket(SOCK_STREAM, host_af)) < 0) return;
2763 if (ip_bind(ident_conn_ctx.sock, host_af, interface_address, 0) < 0)
2765 DEBUG(D_ident) debug_printf("bind socket for ident failed: %s\n",
2770 /* Construct and send the query. */
2772 qlen = snprintf(CS buffer, sizeof(buffer), "%d , %d\r\n",
2773 sender_host_port, interface_port);
2774 early_data.data = buffer;
2775 early_data.len = qlen;
2777 /*XXX we trust that the query is idempotent */
2778 if (ip_connect(ident_conn_ctx.sock, host_af, sender_host_address, port,
2779 rfc1413_query_timeout, &early_data) < 0)
2781 if (errno == ETIMEDOUT && LOGGING(ident_timeout))
2782 log_write(0, LOG_MAIN, "ident connection to %s timed out",
2783 sender_host_address);
2785 DEBUG(D_ident) debug_printf("ident connection to %s failed: %s\n",
2786 sender_host_address, strerror(errno));
2790 /* Read a response line. We put it into the rest of the buffer, using several
2791 recv() calls if necessary. */
2799 int size = sizeof(buffer) - (p - buffer);
2801 if (size <= 0) goto END_OFF; /* Buffer filled without seeing \n. */
2802 count = ip_recv(&ident_conn_ctx, p, size, time(NULL) + rfc1413_query_timeout);
2803 if (count <= 0) goto END_OFF; /* Read error or EOF */
2805 /* Scan what we just read, to see if we have reached the terminating \r\n. Be
2806 generous, and accept a plain \n terminator as well. The only illegal
2809 for (pp = p; pp < p + count; pp++)
2811 if (*pp == 0) goto END_OFF; /* Zero octet not allowed */
2814 if (pp[-1] == '\r') pp--;
2816 goto GOT_DATA; /* Break out of both loops */
2820 /* Reached the end of the data without finding \n. Let the loop continue to
2821 read some more, if there is room. */
2828 /* We have received a line of data. Check it carefully. It must start with the
2829 same two port numbers that we sent, followed by data as defined by the RFC. For
2832 12345 , 25 : USERID : UNIX :root
2834 However, the amount of white space may be different to what we sent. In the
2835 "osname" field there may be several sub-fields, comma separated. The data we
2836 actually want to save follows the third colon. Some systems put leading spaces
2837 in it - we discard those. */
2839 if (sscanf(CS buffer + qlen, "%d , %d%n", &received_sender_port,
2840 &received_interface_port, &n) != 2 ||
2841 received_sender_port != sender_host_port ||
2842 received_interface_port != interface_port)
2845 p = buffer + qlen + n;
2846 while(isspace(*p)) p++;
2847 if (*p++ != ':') goto END_OFF;
2848 while(isspace(*p)) p++;
2849 if (Ustrncmp(p, "USERID", 6) != 0) goto END_OFF;
2851 while(isspace(*p)) p++;
2852 if (*p++ != ':') goto END_OFF;
2853 while (*p != 0 && *p != ':') p++;
2854 if (*p++ == 0) goto END_OFF;
2855 while(isspace(*p)) p++;
2856 if (*p == 0) goto END_OFF;
2858 /* The rest of the line is the data we want. We turn it into printing
2859 characters when we save it, so that it cannot mess up the format of any logging
2860 or Received: lines into which it gets inserted. We keep a maximum of 127
2861 characters. The deconst cast is ok as we fed a nonconst to string_printing() */
2863 sender_ident = US string_printing(string_copyn(p, 127));
2864 DEBUG(D_ident) debug_printf("sender_ident = %s\n", sender_ident);
2867 (void)close(ident_conn_ctx.sock);
2874 /*************************************************
2875 * Match host to a single host-list item *
2876 *************************************************/
2878 /* This function compares a host (name or address) against a single item
2879 from a host list. The host name gets looked up if it is needed and is not
2880 already known. The function is called from verify_check_this_host() via
2881 match_check_list(), which is why most of its arguments are in a single block.
2884 arg the argument block (see below)
2885 ss the host-list item
2886 valueptr where to pass back looked up data, or NULL
2887 error for error message when returning ERROR
2890 host_name (a) the host name, or
2891 (b) NULL, implying use sender_host_name and
2892 sender_host_aliases, looking them up if required, or
2893 (c) the empty string, meaning that only IP address matches
2895 host_address the host address
2896 host_ipv4 the IPv4 address taken from an IPv6 one
2900 DEFER lookup deferred
2901 ERROR (a) failed to find the host name or IP address, or
2902 (b) unknown lookup type specified, or
2903 (c) host name encountered when only IP addresses are
2908 check_host(void * arg, const uschar * ss, const uschar ** valueptr, uschar ** error)
2910 check_host_block * cb = (check_host_block *)arg;
2913 BOOL iplookup = FALSE, isquery = FALSE;
2914 BOOL isiponly = cb->host_name && !cb->host_name[0];
2916 uschar * semicolon, * endname, * opts;
2919 /* Optimize for the special case when the pattern is "*". */
2921 if (*ss == '*' && !ss[1]) return OK;
2923 /* If the pattern is empty, it matches only in the case when there is no host -
2924 this can occur in ACL checking for SMTP input using the -bs option. In this
2925 situation, the host address is the empty string. */
2927 if (!cb->host_address[0]) return *ss ? FAIL : OK;
2928 if (!*ss) return FAIL;
2930 /* If the pattern is precisely "@" then match against the primary host name,
2931 provided that host name matching is permitted; if it's "@[]" match against the
2932 local host's IP addresses. */
2937 if (isiponly) return ERROR;
2938 ss = primary_hostname;
2940 else if (Ustrcmp(ss, "@[]") == 0)
2942 for (ip_address_item * ip = host_find_interfaces(); ip; ip = ip->next)
2943 if (Ustrcmp(ip->address, cb->host_address) == 0) return OK;
2947 /* If the pattern is an IP address, optionally followed by a bitmask count, do
2948 a (possibly masked) comparison with the current IP address. */
2950 if (string_is_ip_address(ss, &maskoffset) != 0)
2951 return (host_is_in_net(cb->host_address, ss, maskoffset)? OK : FAIL);
2953 /* The pattern is not an IP address. A common error that people make is to omit
2954 one component of an IPv4 address, either by accident, or believing that, for
2955 example, 1.2.3/24 is the same as 1.2.3.0/24, or 1.2.3 is the same as 1.2.3.0,
2956 which it isn't. (Those applications that do accept 1.2.3 as an IP address
2957 interpret it as 1.2.0.3 because the final component becomes 16-bit - this is an
2958 ancient specification.) To aid in debugging these cases, we give a specific
2959 error if the pattern contains only digits and dots or contains a slash preceded
2960 only by digits and dots (a slash at the start indicates a file name and of
2961 course slashes may be present in lookups, but not preceded only by digits and
2964 for (t = ss; isdigit(*t) || *t == '.'; ) t++;
2965 if (!*t || (*t == '/' && t != ss))
2967 *error = string_sprintf("malformed IPv4 address or address mask: %.*s", (int)(t - ss), ss);
2971 /* See if there is a semicolon in the pattern, separating a searchtype
2972 prefix. If there is one then check for comma-sep options. */
2974 if ((semicolon = Ustrchr(ss, ';')))
2975 if ((opts = Ustrchr(ss, ',')) && opts < semicolon)
2978 opts = string_copyn(opts, semicolon - opts);
2982 endname = semicolon;
2986 /* If we are doing an IP address only match, then all lookups must be IP
2987 address lookups, even if there is no "net-". */
2990 iplookup = semicolon != NULL;
2992 /* Otherwise, if the item is of the form net[n]-lookup;<file|query> then it is
2993 a lookup on a masked IP network, in textual form. We obey this code even if we
2994 have already set iplookup, so as to skip over the "net-" prefix and to set the
2995 mask length. The net- stuff really only applies to single-key lookups where the
2996 key is implicit. For query-style lookups the key is specified in the query.
2997 From release 4.30, the use of net- for query style is no longer needed, but we
2998 retain it for backward compatibility. */
3000 if (Ustrncmp(ss, "net", 3) == 0 && semicolon)
3003 for (t = ss + 3; isdigit(*t); t++) mlen = mlen * 10 + *t - '0';
3004 if (mlen == 0 && t == ss+3) mlen = -1; /* No mask supplied */
3005 iplookup = *t++ == '-';
3010 /* Do the IP address lookup if that is indeed what we have */
3018 uschar *filename, *key, *result;
3021 /* Find the search type */
3023 search_type = search_findtype(t, endname - t);
3025 if (search_type < 0) log_write(0, LOG_MAIN|LOG_PANIC_DIE, "%s",
3026 search_error_message);
3028 /* Adjust parameters for the type of lookup. For a query-style lookup, there
3029 is no file name, and the "key" is just the query. For query-style with a file
3030 name, we have to fish the file off the start of the query. For a single-key
3031 lookup, the key is the current IP address, masked appropriately, and
3032 reconverted to text form, with the mask appended. For IPv6 addresses, specify
3033 dot separators instead of colons, except when the lookup type is "iplsearch".
3036 if (mac_islookup(search_type, lookup_absfilequery))
3038 filename = semicolon + 1;
3040 while (*key != 0 && !isspace(*key)) key++;
3041 filename = string_copyn(filename, key - filename);
3042 while (isspace(*key)) key++;
3044 else if (mac_islookup(search_type, lookup_querystyle))
3047 key = semicolon + 1;
3049 else /* Single-key style */
3051 int sep = (Ustrcmp(lookup_list[search_type]->name, "iplsearch") == 0)?
3053 insize = host_aton(cb->host_address, incoming);
3054 host_mask(insize, incoming, mlen);
3055 (void)host_nmtoa(insize, incoming, mlen, buffer, sep);
3057 filename = semicolon + 1;
3060 /* Now do the actual lookup; note that there is no search_close() because
3061 of the caching arrangements. */
3063 if (!(handle = search_open(filename, search_type, 0, NULL, NULL)))
3064 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "%s", search_error_message);
3066 result = search_find(handle, filename, key, -1, NULL, 0, 0, NULL, opts);
3067 if (valueptr) *valueptr = result;
3068 return result ? OK : f.search_find_defer ? DEFER: FAIL;
3071 /* The pattern is not an IP address or network reference of any kind. That is,
3072 it is a host name pattern. If this is an IP only match, there's an error in the
3077 *error = US"cannot match host name in match_ip list";
3081 /* Check the characters of the pattern to see if they comprise only letters,
3082 digits, full stops, and hyphens (the constituents of domain names). Allow
3083 underscores, as they are all too commonly found. Sigh. Also, if
3084 allow_utf8_domains is set, allow top-bit characters. */
3086 for (t = ss; *t; t++)
3087 if (!isalnum(*t) && *t != '.' && *t != '-' && *t != '_' &&
3088 (!allow_utf8_domains || *t < 128)) break;
3090 /* If the pattern is a complete domain name, with no fancy characters, look up
3091 its IP address and match against that. Note that a multi-homed host will add
3092 items to the chain. */
3103 /* Using byname rather than bydns here means we cannot determine dnssec
3104 status. On the other hand it is unclear how that could be either
3105 propagated up or enforced. */
3107 rc = host_find_byname(&h, NULL, HOST_FIND_QUALIFY_SINGLE, NULL, FALSE);
3108 if (rc == HOST_FOUND || rc == HOST_FOUND_LOCAL)
3110 for (host_item * hh = &h; hh; hh = hh->next)
3111 if (host_is_in_net(hh->address, cb->host_address, 0)) return OK;
3114 if (rc == HOST_FIND_AGAIN) return DEFER;
3115 *error = string_sprintf("failed to find IP address for %s", ss);
3119 /* Almost all subsequent comparisons require the host name, and can be done
3120 using the general string matching function. When this function is called for
3121 outgoing hosts, the name is always given explicitly. If it is NULL, it means we
3122 must use sender_host_name and its aliases, looking them up if necessary. */
3124 if (cb->host_name) /* Explicit host name given */
3125 return match_check_string(cb->host_name, ss, -1,
3126 MCS_PARTIAL | MCS_CASELESS | MCS_AT_SPECIAL | cb->flags, valueptr);
3128 /* Host name not given; in principle we need the sender host name and its
3129 aliases. However, for query-style lookups, we do not need the name if the
3130 query does not contain $sender_host_name. From release 4.23, a reference to
3131 $sender_host_name causes it to be looked up, so we don't need to do the lookup
3134 if ((semicolon = Ustrchr(ss, ';')))
3136 const uschar * affix, * opts;
3137 int partial, affixlen, starflags, id;
3140 id = search_findtype_partial(ss, &partial, &affix, &affixlen, &starflags,
3144 if (id < 0) /* Unknown lookup type */
3146 log_write(0, LOG_MAIN|LOG_PANIC, "%s in host list item \"%s\"",
3147 search_error_message, ss);
3150 isquery = mac_islookup(id, lookup_querystyle|lookup_absfilequery);
3155 switch(match_check_string(US"", ss, -1,
3156 MCS_PARTIAL| MCS_CASELESS| MCS_AT_SPECIAL | (cb->flags & MCS_CACHEABLE),
3160 case DEFER: return DEFER;
3161 default: return FAIL;
3165 /* Not a query-style lookup; must ensure the host name is present, and then we
3166 do a check on the name and all its aliases. */
3168 if (!sender_host_name)
3170 HDEBUG(D_host_lookup)
3171 debug_printf("sender host name required, to match against %s\n", ss);
3172 if (host_lookup_failed || host_name_lookup() != OK)
3174 *error = string_sprintf("failed to find host name for %s",
3175 sender_host_address);;
3178 host_build_sender_fullhost();
3181 /* Match on the sender host name, using the general matching function */
3183 switch(match_check_string(sender_host_name, ss, -1,
3184 MCS_PARTIAL| MCS_CASELESS| MCS_AT_SPECIAL | (cb->flags & MCS_CACHEABLE),
3188 case DEFER: return DEFER;
3191 /* If there are aliases, try matching on them. */
3193 aliases = sender_host_aliases;
3195 switch(match_check_string(*aliases++, ss, -1,
3196 MCS_PARTIAL| MCS_CASELESS| MCS_AT_SPECIAL | (cb->flags & MCS_CACHEABLE),
3200 case DEFER: return DEFER;
3208 /*************************************************
3209 * Check a specific host matches a host list *
3210 *************************************************/
3212 /* This function is passed a host list containing items in a number of
3213 different formats and the identity of a host. Its job is to determine whether
3214 the given host is in the set of hosts defined by the list. The host name is
3215 passed as a pointer so that it can be looked up if needed and not already
3216 known. This is commonly the case when called from verify_check_host() to check
3217 an incoming connection. When called from elsewhere the host name should usually
3220 This function is now just a front end to match_check_list(), which runs common
3221 code for scanning a list. We pass it the check_host() function to perform a
3225 listptr pointer to the host list
3226 cache_bits pointer to cache for named lists, or NULL
3227 host_name the host name or NULL, implying use sender_host_name and
3228 sender_host_aliases, looking them up if required
3229 host_address the IP address
3230 valueptr if not NULL, data from a lookup is passed back here
3232 Returns: OK if the host is in the defined set
3233 FAIL if the host is not in the defined set,
3234 DEFER if a data lookup deferred (not a host lookup)
3236 If the host name was needed in order to make a comparison, and could not be
3237 determined from the IP address, the result is FAIL unless the item
3238 "+allow_unknown" was met earlier in the list, in which case OK is returned. */
3241 verify_check_this_host(const uschar **listptr, unsigned int *cache_bits,
3242 const uschar *host_name, const uschar *host_address, const uschar **valueptr)
3245 unsigned int *local_cache_bits = cache_bits;
3246 const uschar *save_host_address = deliver_host_address;
3247 check_host_block cb = { .host_name = host_name, .host_address = host_address };
3249 if (valueptr) *valueptr = NULL;
3251 /* If the host address starts off ::ffff: it is an IPv6 address in
3252 IPv4-compatible mode. Find the IPv4 part for checking against IPv4
3255 cb.host_ipv4 = Ustrncmp(host_address, "::ffff:", 7) == 0
3256 ? host_address + 7 : host_address;
3258 /* During the running of the check, put the IP address into $host_address. In
3259 the case of calls from the smtp transport, it will already be there. However,
3260 in other calls (e.g. when testing ignore_target_hosts), it won't. Just to be on
3261 the safe side, any existing setting is preserved, though as I write this
3262 (November 2004) I can't see any cases where it is actually needed. */
3264 deliver_host_address = host_address;
3265 rc = match_check_list(
3266 listptr, /* the list */
3267 0, /* separator character */
3268 &hostlist_anchor, /* anchor pointer */
3269 &local_cache_bits, /* cache pointer */
3270 check_host, /* function for testing */
3271 &cb, /* argument for function */
3272 MCL_HOST, /* type of check */
3273 host_address == sender_host_address
3274 ? US"host" : host_address, /* text for debugging */
3275 valueptr); /* where to pass back data */
3276 deliver_host_address = save_host_address;
3283 /*************************************************
3284 * Check the given host item matches a list *
3285 *************************************************/
3287 verify_check_given_host(const uschar **listptr, const host_item *host)
3289 return verify_check_this_host(listptr, NULL, host->name, host->address, NULL);
3292 /*************************************************
3293 * Check the remote host matches a list *
3294 *************************************************/
3296 /* This is a front end to verify_check_this_host(), created because checking
3297 the remote host is a common occurrence. With luck, a good compiler will spot
3298 the tail recursion and optimize it. If there's no host address, this is
3299 command-line SMTP input - check against an empty string for the address.
3302 listptr pointer to the host list
3304 Returns: the yield of verify_check_this_host(),
3305 i.e. OK, FAIL, or DEFER
3309 verify_check_host(uschar **listptr)
3311 return verify_check_this_host(CUSS listptr, sender_host_cache, NULL,
3312 sender_host_address ? sender_host_address : US"", NULL);
3319 /*************************************************
3320 * Invert an IP address *
3321 *************************************************/
3323 /* Originally just used for DNS xBL lists, now also used for the
3324 reverse_ip expansion operator.
3327 buffer where to put the answer
3328 address the address to invert
3332 invert_address(uschar *buffer, uschar *address)
3335 uschar *bptr = buffer;
3337 /* If this is an IPv4 address mapped into IPv6 format, adjust the pointer
3338 to the IPv4 part only. */
3340 if (Ustrncmp(address, "::ffff:", 7) == 0) address += 7;
3342 /* Handle IPv4 address: when HAVE_IPV6 is false, the result of host_aton() is
3345 if (host_aton(address, bin) == 1)
3348 for (int i = 0; i < 4; i++)
3350 sprintf(CS bptr, "%d.", x & 255);
3351 while (*bptr) bptr++;
3356 /* Handle IPv6 address. Actually, as far as I know, there are no IPv6 addresses
3357 in any DNS black lists, and the format in which they will be looked up is
3358 unknown. This is just a guess. */
3362 for (int j = 3; j >= 0; j--)
3365 for (int i = 0; i < 8; i++)
3367 sprintf(CS bptr, "%x.", x & 15);
3368 while (*bptr) bptr++;
3374 /* Remove trailing period -- this is needed so that both arbitrary
3375 dnsbl keydomains and inverted addresses may be combined with the
3376 same format string, "%s.%s" */
3383 /****************************************************
3384 Verify a local user account for quota sufficiency
3385 ****************************************************/
3387 /* The real work, done via a re-exec for privs, calls
3388 down to the transport for the quota check.
3390 Route and transport (in recipient-verify mode) the
3393 A routing result indicating any transport type other than appendfile
3396 Return, on stdout, a result string containing:
3397 - highlevel result code (OK, DEFER, FAIL)
3404 verify_quota(uschar * address)
3406 address_item vaddr = {.address = address};
3408 uschar * msg = US"\0";
3411 if ((rc = verify_address(&vaddr, NULL, vopt_is_recipient | vopt_quota,
3412 1, 0, 0, NULL, NULL, &routed)) != OK)
3414 uschar * where = recipient_verify_failure;
3415 msg = acl_verify_message ? acl_verify_message : vaddr.message;
3416 if (!msg) msg = US"";
3417 if (rc == DEFER && vaddr.basic_errno == ERRNO_EXIMQUOTA)
3419 rc = FAIL; /* DEFER -> FAIL */
3421 vaddr.basic_errno = 0;
3423 else if (!where) where = US"";
3425 len = 5 + Ustrlen(msg) + 1 + Ustrlen(where);
3426 msg = string_sprintf("%c%c%c%c%c%s%c%s", (uschar)rc,
3427 (vaddr.basic_errno >> 24) & 0xff, (vaddr.basic_errno >> 16) & 0xff,
3428 (vaddr.basic_errno >> 8) & 0xff, vaddr.basic_errno & 0xff,
3432 DEBUG(D_verify) debug_printf_indent("verify_quota: len %d\n", len);
3438 /******************************************************************************/
3440 /* Quota cache lookup. We use the callout hints db also for the quota cache.
3441 Return TRUE if a nonexpired record was found, having filled in the yield
3446 cached_quota_lookup(const uschar * rcpt, int * yield,
3447 int pos_cache, int neg_cache)
3449 open_db dbblock, *dbm_file = NULL;
3450 dbdata_callout_cache_address * cache_address_record;
3452 if (!pos_cache && !neg_cache)
3454 if (!(dbm_file = dbfn_open(US"callout", O_RDWR, &dbblock, FALSE, TRUE)))
3456 HDEBUG(D_verify) debug_printf_indent("quota cache: not available\n");
3459 if (!(cache_address_record = (dbdata_callout_cache_address *)
3460 get_callout_cache_record(dbm_file, rcpt, US"address",
3461 pos_cache, neg_cache)))
3463 dbfn_close(dbm_file);
3466 if (cache_address_record->result == ccache_accept)
3468 dbfn_close(dbm_file);
3472 /* Quota cache write */
3475 cache_quota_write(const uschar * rcpt, int yield, int pos_cache, int neg_cache)
3477 open_db dbblock, *dbm_file = NULL;
3478 dbdata_callout_cache_address cache_address_record;
3480 if (!pos_cache && !neg_cache)
3482 if (!(dbm_file = dbfn_open(US"callout", O_RDWR|O_CREAT, &dbblock, FALSE, TRUE)))
3484 HDEBUG(D_verify) debug_printf_indent("quota cache: not available\n");
3488 cache_address_record.result = yield == OK ? ccache_accept : ccache_reject;
3490 (void)dbfn_write(dbm_file, rcpt, &cache_address_record,
3491 (int)sizeof(dbdata_callout_cache_address));
3492 HDEBUG(D_verify) debug_printf_indent("wrote %s quota cache record for %s\n",
3493 yield == OK ? "positive" : "negative", rcpt);
3495 dbfn_close(dbm_file);
3500 /* To evaluate a local user's quota, starting in ACL, we need to
3501 fork & exec to regain privileges, to that we can change to the user's
3502 identity for access to their files.
3505 rcpt Recipient account
3506 pos_cache Number of seconds to cache a positive result (delivery
3507 to be accepted). Zero to disable caching.
3508 neg_cache Number of seconds to cache a negative result. Zero to disable.
3509 msg Pointer to result string pointer
3511 Return: OK/DEFER/FAIL code
3515 verify_quota_call(const uschar * rcpt, int pos_cache, int neg_cache,
3518 int pfd[2], pid, save_errno, yield = FAIL;
3519 void (*oldsignal)(int);
3520 const uschar * where = US"socketpair";
3524 if (cached_quota_lookup(rcpt, &yield, pos_cache, neg_cache))
3526 HDEBUG(D_verify) debug_printf_indent("quota cache: address record is %s\n",
3527 yield == OK ? "positive" : "negative");
3530 recipient_verify_failure = US"quota";
3531 acl_verify_message = *msg =
3532 US"Previous (cached) quota verification failure";
3541 oldsignal = signal(SIGCHLD, SIG_DFL);
3542 if ((pid = exim_fork(US"quota-verify")) < 0)
3545 close(pfd[pipe_write]);
3546 close(pfd[pipe_read]);
3551 if (pid == 0) /* child */
3553 close(pfd[pipe_read]);
3554 force_fd(pfd[pipe_write], 1); /* stdout to pipe */
3555 close(pfd[pipe_write]);
3557 if (debug_fd > 0) force_fd(debug_fd, 2);
3559 child_exec_exim(CEE_EXEC_EXIT, FALSE, NULL, FALSE, 3,
3560 US"-MCq", string_sprintf("%d", message_size), rcpt);
3565 close(pfd[pipe_write]);
3569 DEBUG(D_verify) debug_printf_indent(" fork: %s\n", strerror(save_errno));
3574 int n = read(pfd[pipe_read], buf, sizeof(buf));
3577 waitpid(pid, &status, 0);
3582 if (n > 0) yield = buf[0];
3584 save_errno = (buf[1] << 24) | (buf[2] << 16) | (buf[3] << 8) | buf[4];
3585 if ((recipient_verify_failure = n > 5
3586 ? string_copyn_taint(buf+5, n-5, GET_UNTAINTED) : NULL))
3589 s = buf + 5 + Ustrlen(recipient_verify_failure) + 1;
3591 acl_verify_message = *msg =
3592 m > 0 ? string_copyn_taint(s, m, GET_UNTAINTED) : NULL;
3595 DEBUG(D_verify) debug_printf_indent("verify call response:"
3596 " len %d yield %s errno '%s' where '%s' msg '%s'\n",
3597 n, rc_names[yield], strerror(save_errno), recipient_verify_failure, *msg);
3600 || save_errno == 0 && Ustrcmp(recipient_verify_failure, "quota") == 0)
3601 cache_quota_write(rcpt, yield, pos_cache, neg_cache);
3602 else DEBUG(D_verify)
3603 debug_printf_indent("result not cacheable\n");
3608 debug_printf_indent("verify call response: waitpid status 0x%04x\n", status);
3612 close(pfd[pipe_read]);
3613 signal(SIGCHLD, oldsignal);
3618 DEBUG(D_verify) debug_printf_indent("verify_quota_call fail in %s\n", where);
3625 /* End of verify.c */