DNS: avoid overflow in cache TTL for negative entries. Bug 1395
[exim.git] / src / src / verify.c
1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
4
5 /* Copyright (c) University of Cambridge 1995 - 2015 */
6 /* See the file NOTICE for conditions of use and distribution. */
7
8 /* Functions concerned with verifying things. The original code for callout
9 caching was contributed by Kevin Fleming (but I hacked it around a bit). */
10
11
12 #include "exim.h"
13 #include "transports/smtp.h"
14
15 #define CUTTHROUGH_CMD_TIMEOUT 30 /* timeout for cutthrough-routing calls */
16 #define CUTTHROUGH_DATA_TIMEOUT 60 /* timeout for cutthrough-routing calls */
17 static smtp_outblock ctblock;
18 uschar ctbuffer[8192];
19
20
21 /* Structure for caching DNSBL lookups */
22
23 typedef struct dnsbl_cache_block {
24 time_t expiry;
25 dns_address *rhs;
26 uschar *text;
27 int rc;
28 BOOL text_set;
29 } dnsbl_cache_block;
30
31
32 /* Anchor for DNSBL cache */
33
34 static tree_node *dnsbl_cache = NULL;
35
36
37 /* Bits for match_type in one_check_dnsbl() */
38
39 #define MT_NOT 1
40 #define MT_ALL 2
41
42 static uschar cutthrough_response(char, uschar **);
43
44
45 /*************************************************
46 * Retrieve a callout cache record *
47 *************************************************/
48
49 /* If a record exists, check whether it has expired.
50
51 Arguments:
52 dbm_file an open hints file
53 key the record key
54 type "address" or "domain"
55 positive_expire expire time for positive records
56 negative_expire expire time for negative records
57
58 Returns: the cache record if a non-expired one exists, else NULL
59 */
60
61 static dbdata_callout_cache *
62 get_callout_cache_record(open_db *dbm_file, const uschar *key, uschar *type,
63 int positive_expire, int negative_expire)
64 {
65 BOOL negative;
66 int length, expire;
67 time_t now;
68 dbdata_callout_cache *cache_record;
69
70 cache_record = dbfn_read_with_length(dbm_file, key, &length);
71
72 if (cache_record == NULL)
73 {
74 HDEBUG(D_verify) debug_printf("callout cache: no %s record found for %s\n", type, key);
75 return NULL;
76 }
77
78 /* We treat a record as "negative" if its result field is not positive, or if
79 it is a domain record and the postmaster field is negative. */
80
81 negative = cache_record->result != ccache_accept ||
82 (type[0] == 'd' && cache_record->postmaster_result == ccache_reject);
83 expire = negative? negative_expire : positive_expire;
84 now = time(NULL);
85
86 if (now - cache_record->time_stamp > expire)
87 {
88 HDEBUG(D_verify) debug_printf("callout cache: %s record expired for %s\n", type, key);
89 return NULL;
90 }
91
92 /* If this is a non-reject domain record, check for the obsolete format version
93 that doesn't have the postmaster and random timestamps, by looking at the
94 length. If so, copy it to a new-style block, replicating the record's
95 timestamp. Then check the additional timestamps. (There's no point wasting
96 effort if connections are rejected.) */
97
98 if (type[0] == 'd' && cache_record->result != ccache_reject)
99 {
100 if (length == sizeof(dbdata_callout_cache_obs))
101 {
102 dbdata_callout_cache *new = store_get(sizeof(dbdata_callout_cache));
103 memcpy(new, cache_record, length);
104 new->postmaster_stamp = new->random_stamp = new->time_stamp;
105 cache_record = new;
106 }
107
108 if (now - cache_record->postmaster_stamp > expire)
109 cache_record->postmaster_result = ccache_unknown;
110
111 if (now - cache_record->random_stamp > expire)
112 cache_record->random_result = ccache_unknown;
113 }
114
115 HDEBUG(D_verify) debug_printf("callout cache: found %s record for %s\n", type, key);
116 return cache_record;
117 }
118
119
120
121 /*************************************************
122 * Do callout verification for an address *
123 *************************************************/
124
125 /* This function is called from verify_address() when the address has routed to
126 a host list, and a callout has been requested. Callouts are expensive; that is
127 why a cache is used to improve the efficiency.
128
129 Arguments:
130 addr the address that's been routed
131 host_list the list of hosts to try
132 tf the transport feedback block
133
134 ifstring "interface" option from transport, or NULL
135 portstring "port" option from transport, or NULL
136 protocolstring "protocol" option from transport, or NULL
137 callout the per-command callout timeout
138 callout_overall the overall callout timeout (if < 0 use 4*callout)
139 callout_connect the callout connection timeout (if < 0 use callout)
140 options the verification options - these bits are used:
141 vopt_is_recipient => this is a recipient address
142 vopt_callout_no_cache => don't use callout cache
143 vopt_callout_fullpm => if postmaster check, do full one
144 vopt_callout_random => do the "random" thing
145 vopt_callout_recipsender => use real sender for recipient
146 vopt_callout_recippmaster => use postmaster for recipient
147 se_mailfrom MAIL FROM address for sender verify; NULL => ""
148 pm_mailfrom if non-NULL, do the postmaster check with this sender
149
150 Returns: OK/FAIL/DEFER
151 */
152
153 static int
154 do_callout(address_item *addr, host_item *host_list, transport_feedback *tf,
155 int callout, int callout_overall, int callout_connect, int options,
156 uschar *se_mailfrom, uschar *pm_mailfrom)
157 {
158 BOOL is_recipient = (options & vopt_is_recipient) != 0;
159 BOOL callout_no_cache = (options & vopt_callout_no_cache) != 0;
160 BOOL callout_random = (options & vopt_callout_random) != 0;
161
162 int yield = OK;
163 int old_domain_cache_result = ccache_accept;
164 BOOL done = FALSE;
165 uschar *address_key;
166 uschar *from_address;
167 uschar *random_local_part = NULL;
168 const uschar *save_deliver_domain = deliver_domain;
169 uschar **failure_ptr = is_recipient?
170 &recipient_verify_failure : &sender_verify_failure;
171 open_db dbblock;
172 open_db *dbm_file = NULL;
173 dbdata_callout_cache new_domain_record;
174 dbdata_callout_cache_address new_address_record;
175 host_item *host;
176 time_t callout_start_time;
177 #ifdef EXPERIMENTAL_INTERNATIONAL
178 BOOL utf8_offered = FALSE;
179 #endif
180
181 new_domain_record.result = ccache_unknown;
182 new_domain_record.postmaster_result = ccache_unknown;
183 new_domain_record.random_result = ccache_unknown;
184
185 memset(&new_address_record, 0, sizeof(new_address_record));
186
187 /* For a recipient callout, the key used for the address cache record must
188 include the sender address if we are using the real sender in the callout,
189 because that may influence the result of the callout. */
190
191 address_key = addr->address;
192 from_address = US"";
193
194 if (is_recipient)
195 {
196 if (options & vopt_callout_recipsender)
197 {
198 address_key = string_sprintf("%s/<%s>", addr->address, sender_address);
199 from_address = sender_address;
200 }
201 else if (options & vopt_callout_recippmaster)
202 {
203 address_key = string_sprintf("%s/<postmaster@%s>", addr->address,
204 qualify_domain_sender);
205 from_address = string_sprintf("postmaster@%s", qualify_domain_sender);
206 }
207 }
208
209 /* For a sender callout, we must adjust the key if the mailfrom address is not
210 empty. */
211
212 else
213 {
214 from_address = (se_mailfrom == NULL)? US"" : se_mailfrom;
215 if (from_address[0] != 0)
216 address_key = string_sprintf("%s/<%s>", addr->address, from_address);
217 }
218
219 /* Open the callout cache database, it it exists, for reading only at this
220 stage, unless caching has been disabled. */
221
222 if (callout_no_cache)
223 {
224 HDEBUG(D_verify) debug_printf("callout cache: disabled by no_cache\n");
225 }
226 else if ((dbm_file = dbfn_open(US"callout", O_RDWR, &dbblock, FALSE)) == NULL)
227 {
228 HDEBUG(D_verify) debug_printf("callout cache: not available\n");
229 }
230
231 /* If a cache database is available see if we can avoid the need to do an
232 actual callout by making use of previously-obtained data. */
233
234 if (dbm_file != NULL)
235 {
236 dbdata_callout_cache_address *cache_address_record;
237 dbdata_callout_cache *cache_record = get_callout_cache_record(dbm_file,
238 addr->domain, US"domain",
239 callout_cache_domain_positive_expire,
240 callout_cache_domain_negative_expire);
241
242 /* If an unexpired cache record was found for this domain, see if the callout
243 process can be short-circuited. */
244
245 if (cache_record != NULL)
246 {
247 /* In most cases, if an early command (up to and including MAIL FROM:<>)
248 was rejected, there is no point carrying on. The callout fails. However, if
249 we are doing a recipient verification with use_sender or use_postmaster
250 set, a previous failure of MAIL FROM:<> doesn't count, because this time we
251 will be using a non-empty sender. We have to remember this situation so as
252 not to disturb the cached domain value if this whole verification succeeds
253 (we don't want it turning into "accept"). */
254
255 old_domain_cache_result = cache_record->result;
256
257 if (cache_record->result == ccache_reject ||
258 (*from_address == 0 && cache_record->result == ccache_reject_mfnull))
259 {
260 setflag(addr, af_verify_nsfail);
261 HDEBUG(D_verify)
262 debug_printf("callout cache: domain gave initial rejection, or "
263 "does not accept HELO or MAIL FROM:<>\n");
264 setflag(addr, af_verify_nsfail);
265 addr->user_message = US"(result of an earlier callout reused).";
266 yield = FAIL;
267 *failure_ptr = US"mail";
268 goto END_CALLOUT;
269 }
270
271 /* If a previous check on a "random" local part was accepted, we assume
272 that the server does not do any checking on local parts. There is therefore
273 no point in doing the callout, because it will always be successful. If a
274 random check previously failed, arrange not to do it again, but preserve
275 the data in the new record. If a random check is required but hasn't been
276 done, skip the remaining cache processing. */
277
278 if (callout_random) switch(cache_record->random_result)
279 {
280 case ccache_accept:
281 HDEBUG(D_verify)
282 debug_printf("callout cache: domain accepts random addresses\n");
283 goto END_CALLOUT; /* Default yield is OK */
284
285 case ccache_reject:
286 HDEBUG(D_verify)
287 debug_printf("callout cache: domain rejects random addresses\n");
288 callout_random = FALSE;
289 new_domain_record.random_result = ccache_reject;
290 new_domain_record.random_stamp = cache_record->random_stamp;
291 break;
292
293 default:
294 HDEBUG(D_verify)
295 debug_printf("callout cache: need to check random address handling "
296 "(not cached or cache expired)\n");
297 goto END_CACHE;
298 }
299
300 /* If a postmaster check is requested, but there was a previous failure,
301 there is again no point in carrying on. If a postmaster check is required,
302 but has not been done before, we are going to have to do a callout, so skip
303 remaining cache processing. */
304
305 if (pm_mailfrom != NULL)
306 {
307 if (cache_record->postmaster_result == ccache_reject)
308 {
309 setflag(addr, af_verify_pmfail);
310 HDEBUG(D_verify)
311 debug_printf("callout cache: domain does not accept "
312 "RCPT TO:<postmaster@domain>\n");
313 yield = FAIL;
314 *failure_ptr = US"postmaster";
315 setflag(addr, af_verify_pmfail);
316 addr->user_message = US"(result of earlier verification reused).";
317 goto END_CALLOUT;
318 }
319 if (cache_record->postmaster_result == ccache_unknown)
320 {
321 HDEBUG(D_verify)
322 debug_printf("callout cache: need to check RCPT "
323 "TO:<postmaster@domain> (not cached or cache expired)\n");
324 goto END_CACHE;
325 }
326
327 /* If cache says OK, set pm_mailfrom NULL to prevent a redundant
328 postmaster check if the address itself has to be checked. Also ensure
329 that the value in the cache record is preserved (with its old timestamp).
330 */
331
332 HDEBUG(D_verify) debug_printf("callout cache: domain accepts RCPT "
333 "TO:<postmaster@domain>\n");
334 pm_mailfrom = NULL;
335 new_domain_record.postmaster_result = ccache_accept;
336 new_domain_record.postmaster_stamp = cache_record->postmaster_stamp;
337 }
338 }
339
340 /* We can't give a result based on information about the domain. See if there
341 is an unexpired cache record for this specific address (combined with the
342 sender address if we are doing a recipient callout with a non-empty sender).
343 */
344
345 cache_address_record = (dbdata_callout_cache_address *)
346 get_callout_cache_record(dbm_file,
347 address_key, US"address",
348 callout_cache_positive_expire,
349 callout_cache_negative_expire);
350
351 if (cache_address_record != NULL)
352 {
353 if (cache_address_record->result == ccache_accept)
354 {
355 HDEBUG(D_verify)
356 debug_printf("callout cache: address record is positive\n");
357 }
358 else
359 {
360 HDEBUG(D_verify)
361 debug_printf("callout cache: address record is negative\n");
362 addr->user_message = US"Previous (cached) callout verification failure";
363 *failure_ptr = US"recipient";
364 yield = FAIL;
365 }
366 goto END_CALLOUT;
367 }
368
369 /* Close the cache database while we actually do the callout for real. */
370
371 END_CACHE:
372 dbfn_close(dbm_file);
373 dbm_file = NULL;
374 }
375
376 if (!addr->transport)
377 {
378 HDEBUG(D_verify) debug_printf("cannot callout via null transport\n");
379 }
380 else if (Ustrcmp(addr->transport->driver_name, "smtp") != 0)
381 log_write(0, LOG_MAIN|LOG_PANIC|LOG_CONFIG_FOR, "callout transport '%s': %s is non-smtp",
382 addr->transport->name, addr->transport->driver_name);
383 else
384 {
385 smtp_transport_options_block *ob =
386 (smtp_transport_options_block *)addr->transport->options_block;
387
388 /* The information wasn't available in the cache, so we have to do a real
389 callout and save the result in the cache for next time, unless no_cache is set,
390 or unless we have a previously cached negative random result. If we are to test
391 with a random local part, ensure that such a local part is available. If not,
392 log the fact, but carry on without randomming. */
393
394 if (callout_random && callout_random_local_part != NULL)
395 if (!(random_local_part = expand_string(callout_random_local_part)))
396 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand "
397 "callout_random_local_part: %s", expand_string_message);
398
399 /* Default the connect and overall callout timeouts if not set, and record the
400 time we are starting so that we can enforce it. */
401
402 if (callout_overall < 0) callout_overall = 4 * callout;
403 if (callout_connect < 0) callout_connect = callout;
404 callout_start_time = time(NULL);
405
406 /* Before doing a real callout, if this is an SMTP connection, flush the SMTP
407 output because a callout might take some time. When PIPELINING is active and
408 there are many recipients, the total time for doing lots of callouts can add up
409 and cause the client to time out. So in this case we forgo the PIPELINING
410 optimization. */
411
412 if (smtp_out != NULL && !disable_callout_flush) mac_smtp_fflush();
413
414 /* cutthrough-multi: if a nonfirst rcpt has the same routing as the first,
415 and we are holding a cutthrough conn open, we can just append the rcpt to
416 that conn for verification purposes (and later delivery also). Simplest
417 coding means skipping this whole loop and doing the append separately.
418
419 We will need to remember it has been appended so that rcpt-acl tail code
420 can do it there for the non-rcpt-verify case. For this we keep an addresscount.
421 */
422
423 /* Can we re-use an open cutthrough connection? */
424 if ( cutthrough.fd >= 0
425 && (options & (vopt_callout_recipsender | vopt_callout_recippmaster))
426 == vopt_callout_recipsender
427 && !random_local_part
428 && !pm_mailfrom
429 )
430 {
431 if (addr->transport == cutthrough.addr.transport)
432 for (host = host_list; host; host = host->next)
433 if (Ustrcmp(host->address, cutthrough.host.address) == 0)
434 {
435 int host_af;
436 uschar *interface = NULL; /* Outgoing interface to use; NULL => any */
437 int port = 25;
438
439 deliver_host = host->name;
440 deliver_host_address = host->address;
441 deliver_host_port = host->port;
442 deliver_domain = addr->domain;
443 transport_name = addr->transport->name;
444
445 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET:AF_INET6;
446
447 if (!smtp_get_interface(tf->interface, host_af, addr, &interface,
448 US"callout") ||
449 !smtp_get_port(tf->port, addr, &port, US"callout"))
450 log_write(0, LOG_MAIN|LOG_PANIC, "<%s>: %s", addr->address,
451 addr->message);
452
453 if ( ( interface == cutthrough.interface
454 || ( interface
455 && cutthrough.interface
456 && Ustrcmp(interface, cutthrough.interface) == 0
457 ) )
458 && port == cutthrough.host.port
459 )
460 {
461 uschar * resp;
462
463 /* Match! Send the RCPT TO, append the addr, set done */
464 done =
465 smtp_write_command(&ctblock, FALSE, "RCPT TO:<%.1000s>\r\n",
466 transport_rcpt_address(addr,
467 (addr->transport == NULL)? FALSE :
468 addr->transport->rcpt_include_affixes)) >= 0 &&
469 cutthrough_response('2', &resp) == '2';
470
471 /* This would go horribly wrong if a callout fail was ignored by ACL.
472 We punt by abandoning cutthrough on a reject, like the
473 first-rcpt does. */
474
475 if (done)
476 {
477 address_item * na = store_get(sizeof(address_item));
478 *na = cutthrough.addr;
479 cutthrough.addr = *addr;
480 cutthrough.addr.host_used = &cutthrough.host;
481 cutthrough.addr.next = na;
482
483 cutthrough.nrcpt++;
484 }
485 else
486 {
487 cancel_cutthrough_connection("recipient rejected");
488 if (errno == ETIMEDOUT)
489 {
490 HDEBUG(D_verify) debug_printf("SMTP timeout\n");
491 }
492 else if (errno == 0)
493 {
494 if (*resp == 0)
495 Ustrcpy(resp, US"connection dropped");
496
497 addr->message =
498 string_sprintf("response to \"%s\" from %s [%s] was: %s",
499 big_buffer, host->name, host->address,
500 string_printing(resp));
501
502 addr->user_message =
503 string_sprintf("Callout verification failed:\n%s", resp);
504
505 /* Hard rejection ends the process */
506
507 if (resp[0] == '5') /* Address rejected */
508 {
509 yield = FAIL;
510 done = TRUE;
511 }
512 }
513 }
514 }
515 break;
516 }
517 if (!done)
518 cancel_cutthrough_connection("incompatible connection");
519 }
520
521 /* Now make connections to the hosts and do real callouts. The list of hosts
522 is passed in as an argument. */
523
524 for (host = host_list; host != NULL && !done; host = host->next)
525 {
526 smtp_inblock inblock;
527 smtp_outblock outblock;
528 int host_af;
529 int port = 25;
530 BOOL send_quit = TRUE;
531 uschar *active_hostname = smtp_active_hostname;
532 BOOL lmtp;
533 BOOL smtps;
534 BOOL esmtp;
535 BOOL suppress_tls = FALSE;
536 uschar *interface = NULL; /* Outgoing interface to use; NULL => any */
537 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
538 BOOL dane = FALSE;
539 BOOL dane_required;
540 dns_answer tlsa_dnsa;
541 #endif
542 uschar inbuffer[4096];
543 uschar outbuffer[1024];
544 uschar responsebuffer[4096];
545
546 clearflag(addr, af_verify_pmfail); /* postmaster callout flag */
547 clearflag(addr, af_verify_nsfail); /* null sender callout flag */
548
549 /* Skip this host if we don't have an IP address for it. */
550
551 if (host->address == NULL)
552 {
553 DEBUG(D_verify) debug_printf("no IP address for host name %s: skipping\n",
554 host->name);
555 continue;
556 }
557
558 /* Check the overall callout timeout */
559
560 if (time(NULL) - callout_start_time >= callout_overall)
561 {
562 HDEBUG(D_verify) debug_printf("overall timeout for callout exceeded\n");
563 break;
564 }
565
566 /* Set IPv4 or IPv6 */
567
568 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET:AF_INET6;
569
570 /* Expand and interpret the interface and port strings. The latter will not
571 be used if there is a host-specific port (e.g. from a manualroute router).
572 This has to be delayed till now, because they may expand differently for
573 different hosts. If there's a failure, log it, but carry on with the
574 defaults. */
575
576 deliver_host = host->name;
577 deliver_host_address = host->address;
578 deliver_host_port = host->port;
579 deliver_domain = addr->domain;
580 transport_name = addr->transport->name;
581
582 if ( !smtp_get_interface(tf->interface, host_af, addr, &interface,
583 US"callout")
584 || !smtp_get_port(tf->port, addr, &port, US"callout")
585 )
586 log_write(0, LOG_MAIN|LOG_PANIC, "<%s>: %s", addr->address,
587 addr->message);
588
589 /* Set HELO string according to the protocol */
590 lmtp= Ustrcmp(tf->protocol, "lmtp") == 0;
591 smtps= Ustrcmp(tf->protocol, "smtps") == 0;
592
593
594 HDEBUG(D_verify) debug_printf("interface=%s port=%d\n", interface, port);
595
596 /* Set up the buffer for reading SMTP response packets. */
597
598 inblock.buffer = inbuffer;
599 inblock.buffersize = sizeof(inbuffer);
600 inblock.ptr = inbuffer;
601 inblock.ptrend = inbuffer;
602
603 /* Set up the buffer for holding SMTP commands while pipelining */
604
605 outblock.buffer = outbuffer;
606 outblock.buffersize = sizeof(outbuffer);
607 outblock.ptr = outbuffer;
608 outblock.cmd_count = 0;
609 outblock.authenticating = FALSE;
610
611 /* Connect to the host; on failure, just loop for the next one, but we
612 set the error for the last one. Use the callout_connect timeout. */
613
614 tls_retry_connection:
615
616 /* Reset the parameters of a TLS session */
617 tls_out.cipher = tls_out.peerdn = tls_out.peercert = NULL;
618
619 inblock.sock = outblock.sock =
620 smtp_connect(host, host_af, port, interface, callout_connect,
621 addr->transport);
622 if (inblock.sock < 0)
623 {
624 addr->message = string_sprintf("could not connect to %s [%s]: %s",
625 host->name, host->address, strerror(errno));
626 transport_name = NULL;
627 deliver_host = deliver_host_address = NULL;
628 deliver_domain = save_deliver_domain;
629 continue;
630 }
631
632 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
633 {
634 int rc;
635
636 tls_out.dane_verified = FALSE;
637 tls_out.tlsa_usage = 0;
638
639 dane_required =
640 verify_check_given_host(&ob->hosts_require_dane, host) == OK;
641
642 if (host->dnssec == DS_YES)
643 {
644 if( ( dane_required
645 || verify_check_given_host(&ob->hosts_try_dane, host) == OK
646 )
647 && (rc = tlsa_lookup(host, &tlsa_dnsa, dane_required, &dane)) != OK
648 )
649 return rc;
650 }
651 else if (dane_required)
652 {
653 log_write(0, LOG_MAIN, "DANE error: %s lookup not DNSSEC", host->name);
654 return FAIL;
655 }
656
657 if (dane)
658 ob->tls_tempfail_tryclear = FALSE;
659 }
660 #endif /*DANE*/
661
662 /* Expand the helo_data string to find the host name to use. */
663
664 if (tf->helo_data != NULL)
665 {
666 uschar *s = expand_string(tf->helo_data);
667 if (s == NULL)
668 log_write(0, LOG_MAIN|LOG_PANIC, "<%s>: failed to expand transport's "
669 "helo_data value for callout: %s", addr->address,
670 expand_string_message);
671 else active_hostname = s;
672 }
673
674 /* Wait for initial response, and send HELO. The smtp_write_command()
675 function leaves its command in big_buffer. This is used in error responses.
676 Initialize it in case the connection is rejected. */
677
678 Ustrcpy(big_buffer, "initial connection");
679
680 /* Unless ssl-on-connect, wait for the initial greeting */
681 smtps_redo_greeting:
682
683 #ifdef SUPPORT_TLS
684 if (!smtps || (smtps && tls_out.active >= 0))
685 #endif
686 {
687 if (!(done= smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer), '2', callout)))
688 goto RESPONSE_FAILED;
689
690 #ifdef EXPERIMENTAL_EVENT
691 lookup_dnssec_authenticated = host->dnssec==DS_YES ? US"yes"
692 : host->dnssec==DS_NO ? US"no" : NULL;
693 if (event_raise(addr->transport->event_action,
694 US"smtp:connect", responsebuffer))
695 {
696 lookup_dnssec_authenticated = NULL;
697 /* Logging? Debug? */
698 goto RESPONSE_FAILED;
699 }
700 lookup_dnssec_authenticated = NULL;
701 #endif
702 }
703
704 /* Not worth checking greeting line for ESMTP support */
705 if (!(esmtp = verify_check_given_host(&ob->hosts_avoid_esmtp, host) != OK))
706 DEBUG(D_transport)
707 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
708
709 tls_redo_helo:
710
711 #ifdef SUPPORT_TLS
712 if (smtps && tls_out.active < 0) /* ssl-on-connect, first pass */
713 {
714 tls_offered = TRUE;
715 ob->tls_tempfail_tryclear = FALSE;
716 }
717 else /* all other cases */
718 #endif
719
720 { esmtp_retry:
721
722 if (!(done= smtp_write_command(&outblock, FALSE, "%s %s\r\n",
723 !esmtp? "HELO" : lmtp? "LHLO" : "EHLO", active_hostname) >= 0))
724 goto SEND_FAILED;
725 if (!smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer), '2', callout))
726 {
727 if (errno != 0 || responsebuffer[0] == 0 || lmtp || !esmtp || tls_out.active >= 0)
728 {
729 done= FALSE;
730 goto RESPONSE_FAILED;
731 }
732 #ifdef SUPPORT_TLS
733 tls_offered = FALSE;
734 #endif
735 esmtp = FALSE;
736 goto esmtp_retry; /* fallback to HELO */
737 }
738
739 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
740 #ifdef SUPPORT_TLS
741 if (esmtp && !suppress_tls && tls_out.active < 0)
742 {
743 if (regex_STARTTLS == NULL) regex_STARTTLS =
744 regex_must_compile(US"\\n250[\\s\\-]STARTTLS(\\s|\\n|$)", FALSE, TRUE);
745
746 tls_offered = pcre_exec(regex_STARTTLS, NULL, CS responsebuffer,
747 Ustrlen(responsebuffer), 0, PCRE_EOPT, NULL, 0) >= 0;
748 }
749 else
750 tls_offered = FALSE;
751 #endif
752 }
753
754 /* If TLS is available on this connection attempt to
755 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
756 send another EHLO - the server may give a different answer in secure mode. We
757 use a separate buffer for reading the response to STARTTLS so that if it is
758 negative, the original EHLO data is available for subsequent analysis, should
759 the client not be required to use TLS. If the response is bad, copy the buffer
760 for error analysis. */
761
762 #ifdef SUPPORT_TLS
763 if ( tls_offered
764 && verify_check_given_host(&ob->hosts_avoid_tls, host) != OK
765 && verify_check_given_host(&ob->hosts_verify_avoid_tls, host) != OK
766 )
767 {
768 uschar buffer2[4096];
769 if ( !smtps
770 && !(done= smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") >= 0))
771 goto SEND_FAILED;
772
773 /* If there is an I/O error, transmission of this message is deferred. If
774 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
775 false, we also defer. However, if there is a temporary rejection of STARTTLS
776 and tls_tempfail_tryclear is true, or if there is an outright rejection of
777 STARTTLS, we carry on. This means we will try to send the message in clear,
778 unless the host is in hosts_require_tls (tested below). */
779
780 if (!smtps && !smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
781 ob->command_timeout))
782 {
783 if (errno != 0 || buffer2[0] == 0 ||
784 (buffer2[0] == '4' && !ob->tls_tempfail_tryclear))
785 {
786 Ustrncpy(responsebuffer, buffer2, sizeof(responsebuffer));
787 done= FALSE;
788 goto RESPONSE_FAILED;
789 }
790 }
791
792 /* STARTTLS accepted or ssl-on-connect: try to negotiate a TLS session. */
793 else
794 {
795 int oldtimeout = ob->command_timeout;
796 int rc;
797
798 tls_negotiate:
799 ob->command_timeout = callout;
800 rc = tls_client_start(inblock.sock, host, addr, addr->transport
801 # ifdef EXPERIMENTAL_DANE
802 , dane ? &tlsa_dnsa : NULL
803 # endif
804 );
805 ob->command_timeout = oldtimeout;
806
807 /* TLS negotiation failed; give an error. Try in clear on a new
808 connection, if the options permit it for this host. */
809 if (rc != OK)
810 {
811 if (rc == DEFER)
812 {
813 (void)close(inblock.sock);
814 # ifdef EXPERIMENTAL_EVENT
815 (void) event_raise(addr->transport->event_action,
816 US"tcp:close", NULL);
817 # endif
818 # ifdef EXPERIMENTAL_DANE
819 if (dane)
820 {
821 if (!dane_required)
822 {
823 log_write(0, LOG_MAIN, "DANE attempt failed;"
824 " trying CA-root TLS to %s [%s] (not in hosts_require_dane)",
825 host->name, host->address);
826 dane = FALSE;
827 goto tls_negotiate;
828 }
829 }
830 else
831 # endif
832 if ( ob->tls_tempfail_tryclear
833 && !smtps
834 && verify_check_given_host(&ob->hosts_require_tls, host) != OK
835 )
836 {
837 log_write(0, LOG_MAIN, "TLS session failure:"
838 " delivering unencrypted to %s [%s] (not in hosts_require_tls)",
839 host->name, host->address);
840 suppress_tls = TRUE;
841 goto tls_retry_connection;
842 }
843 }
844
845 /*save_errno = ERRNO_TLSFAILURE;*/
846 /*message = US"failure while setting up TLS session";*/
847 send_quit = FALSE;
848 done= FALSE;
849 goto TLS_FAILED;
850 }
851
852 /* TLS session is set up. Copy info for logging. */
853 addr->cipher = tls_out.cipher;
854 addr->peerdn = tls_out.peerdn;
855
856 /* For SMTPS we need to wait for the initial OK response, then do HELO. */
857 if (smtps)
858 goto smtps_redo_greeting;
859
860 /* For STARTTLS we need to redo EHLO */
861 goto tls_redo_helo;
862 }
863 }
864
865 /* If the host is required to use a secure channel, ensure that we have one. */
866 if (tls_out.active < 0)
867 if (
868 # ifdef EXPERIMENTAL_DANE
869 dane ||
870 # endif
871 verify_check_given_host(&ob->hosts_require_tls, host) == OK
872 )
873 {
874 /*save_errno = ERRNO_TLSREQUIRED;*/
875 log_write(0, LOG_MAIN,
876 "H=%s [%s]: a TLS session is required for this host, but %s",
877 host->name, host->address,
878 tls_offered ? "an attempt to start TLS failed"
879 : "the server did not offer TLS support");
880 done= FALSE;
881 goto TLS_FAILED;
882 }
883
884 #endif /*SUPPORT_TLS*/
885
886 done = TRUE; /* so far so good; have response to HELO */
887
888 /*XXX the EHLO response would be analyzed here for IGNOREQUOTA, SIZE, PIPELINING */
889
890 /* For now, transport_filter by cutthrough-delivery is not supported */
891 /* Need proper integration with the proper transport mechanism. */
892 if (cutthrough.delivery)
893 {
894 if (addr->transport->filter_command)
895 {
896 cutthrough.delivery = FALSE;
897 HDEBUG(D_acl|D_v) debug_printf("Cutthrough cancelled by presence of transport filter\n");
898 }
899 #ifndef DISABLE_DKIM
900 if (ob->dkim_domain)
901 {
902 cutthrough.delivery = FALSE;
903 HDEBUG(D_acl|D_v) debug_printf("Cutthrough cancelled by presence of DKIM signing\n");
904 }
905 #endif
906 }
907
908 SEND_FAILED:
909 RESPONSE_FAILED:
910 TLS_FAILED:
911 ;
912 /* Clear down of the TLS, SMTP and TCP layers on error is handled below. */
913
914 /* Failure to accept HELO is cached; this blocks the whole domain for all
915 senders. I/O errors and defer responses are not cached. */
916
917 if (!done)
918 {
919 *failure_ptr = US"mail"; /* At or before MAIL */
920 if (errno == 0 && responsebuffer[0] == '5')
921 {
922 setflag(addr, af_verify_nsfail);
923 new_domain_record.result = ccache_reject;
924 }
925 }
926
927 #ifdef EXPERIMENTAL_INTERNATIONAL
928 else if ( addr->prop.utf8_msg
929 && !addr->prop.utf8_downcvt
930 && !( esmtp
931 && ( regex_UTF8
932 || ( (regex_UTF8 = regex_must_compile(
933 US"\\n250[\\s\\-]SMTPUTF8(\\s|\\n|$)", FALSE, TRUE)),
934 TRUE
935 ) )
936 && ( (utf8_offered = pcre_exec(regex_UTF8, NULL,
937 CS responsebuffer, Ustrlen(responsebuffer),
938 0, PCRE_EOPT, NULL, 0) >= 0)
939 || addr->prop.utf8_downcvt_maybe
940 ) ) )
941 {
942 HDEBUG(D_acl|D_v) debug_printf("utf8 required but not offered\n");
943 errno = ERRNO_UTF8_FWD;
944 setflag(addr, af_verify_nsfail);
945 done = FALSE;
946 }
947 else if ( addr->prop.utf8_msg
948 && (addr->prop.utf8_downcvt || !utf8_offered)
949 && (setflag(addr, af_utf8_downcvt),
950 from_address = string_address_utf8_to_alabel(from_address,
951 &addr->message),
952 addr->message
953 ) )
954 {
955 errno = ERRNO_EXPANDFAIL;
956 setflag(addr, af_verify_nsfail);
957 done = FALSE;
958 }
959 #endif
960
961 /* If we haven't authenticated, but are required to, give up. */
962 /* Try to AUTH */
963
964 else done = smtp_auth(responsebuffer, sizeof(responsebuffer),
965 addr, host, ob, esmtp, &inblock, &outblock) == OK &&
966
967 /* Copy AUTH info for logging */
968 ( (addr->authenticator = client_authenticator),
969 (addr->auth_id = client_authenticated_id),
970
971 /* Build a mail-AUTH string (re-using responsebuffer for convenience */
972 !smtp_mail_auth_str(responsebuffer, sizeof(responsebuffer), addr, ob)
973 ) &&
974
975 ( (addr->auth_sndr = client_authenticated_sender),
976
977 /* Send the MAIL command */
978 (smtp_write_command(&outblock, FALSE,
979 #ifdef EXPERIMENTAL_INTERNATIONAL
980 addr->prop.utf8_msg && !addr->prop.utf8_downcvt
981 ? "MAIL FROM:<%s>%s SMTPUTF8\r\n"
982 :
983 #endif
984 "MAIL FROM:<%s>%s\r\n",
985 from_address, responsebuffer) >= 0)
986 ) &&
987
988 smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer),
989 '2', callout);
990
991 deliver_host = deliver_host_address = NULL;
992 deliver_domain = save_deliver_domain;
993
994 /* If the host does not accept MAIL FROM:<>, arrange to cache this
995 information, but again, don't record anything for an I/O error or a defer. Do
996 not cache rejections of MAIL when a non-empty sender has been used, because
997 that blocks the whole domain for all senders. */
998
999 if (!done)
1000 {
1001 *failure_ptr = US"mail"; /* At or before MAIL */
1002 if (errno == 0 && responsebuffer[0] == '5')
1003 {
1004 setflag(addr, af_verify_nsfail);
1005 if (from_address[0] == 0)
1006 new_domain_record.result = ccache_reject_mfnull;
1007 }
1008 }
1009
1010 /* Otherwise, proceed to check a "random" address (if required), then the
1011 given address, and the postmaster address (if required). Between each check,
1012 issue RSET, because some servers accept only one recipient after MAIL
1013 FROM:<>.
1014
1015 Before doing this, set the result in the domain cache record to "accept",
1016 unless its previous value was ccache_reject_mfnull. In that case, the domain
1017 rejects MAIL FROM:<> and we want to continue to remember that. When that is
1018 the case, we have got here only in the case of a recipient verification with
1019 a non-null sender. */
1020
1021 else
1022 {
1023 const uschar * rcpt_domain = addr->domain;
1024
1025 #ifdef EXPERIMENTAL_INTERNATIONAL
1026 uschar * errstr = NULL;
1027 if ( testflag(addr, af_utf8_downcvt)
1028 && (rcpt_domain = string_domain_utf8_to_alabel(rcpt_domain,
1029 &errstr), errstr)
1030 )
1031 {
1032 addr->message = errstr;
1033 errno = ERRNO_EXPANDFAIL;
1034 setflag(addr, af_verify_nsfail);
1035 done = FALSE;
1036 rcpt_domain = US""; /*XXX errorhandling! */
1037 }
1038 #endif
1039
1040 new_domain_record.result =
1041 (old_domain_cache_result == ccache_reject_mfnull)?
1042 ccache_reject_mfnull: ccache_accept;
1043
1044 /* Do the random local part check first */
1045
1046 if (random_local_part != NULL)
1047 {
1048 uschar randombuffer[1024];
1049 BOOL random_ok =
1050 smtp_write_command(&outblock, FALSE,
1051 "RCPT TO:<%.1000s@%.1000s>\r\n", random_local_part,
1052 rcpt_domain) >= 0 &&
1053 smtp_read_response(&inblock, randombuffer,
1054 sizeof(randombuffer), '2', callout);
1055
1056 /* Remember when we last did a random test */
1057
1058 new_domain_record.random_stamp = time(NULL);
1059
1060 /* If accepted, we aren't going to do any further tests below. */
1061
1062 if (random_ok)
1063 new_domain_record.random_result = ccache_accept;
1064
1065 /* Otherwise, cache a real negative response, and get back to the right
1066 state to send RCPT. Unless there's some problem such as a dropped
1067 connection, we expect to succeed, because the commands succeeded above.
1068 However, some servers drop the connection after responding to an
1069 invalid recipient, so on (any) error we drop and remake the connection.
1070 */
1071
1072 else if (errno == 0)
1073 {
1074 /* This would be ok for 1st rcpt a cutthrough, but no way to
1075 handle a subsequent. So refuse to support any */
1076 cancel_cutthrough_connection("random-recipient");
1077
1078 if (randombuffer[0] == '5')
1079 new_domain_record.random_result = ccache_reject;
1080
1081 done =
1082 smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0 &&
1083 smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer),
1084 '2', callout) &&
1085
1086 smtp_write_command(&outblock, FALSE,
1087 #ifdef EXPERIMENTAL_INTERNATIONAL
1088 addr->prop.utf8_msg && !addr->prop.utf8_downcvt
1089 ? "MAIL FROM:<%s> SMTPUTF8\r\n"
1090 :
1091 #endif
1092 "MAIL FROM:<%s>\r\n",
1093 from_address) >= 0 &&
1094 smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer),
1095 '2', callout);
1096
1097 if (!done)
1098 {
1099 HDEBUG(D_acl|D_v)
1100 debug_printf("problem after random/rset/mfrom; reopen conn\n");
1101 random_local_part = NULL;
1102 #ifdef SUPPORT_TLS
1103 tls_close(FALSE, TRUE);
1104 #endif
1105 (void)close(inblock.sock);
1106 #ifdef EXPERIMENTAL_EVENT
1107 (void) event_raise(addr->transport->event_action,
1108 US"tcp:close", NULL);
1109 #endif
1110 goto tls_retry_connection;
1111 }
1112 }
1113 else done = FALSE; /* Some timeout/connection problem */
1114 } /* Random check */
1115
1116 /* If the host is accepting all local parts, as determined by the "random"
1117 check, we don't need to waste time doing any further checking. */
1118
1119 if (new_domain_record.random_result != ccache_accept && done)
1120 {
1121 /* Get the rcpt_include_affixes flag from the transport if there is one,
1122 but assume FALSE if there is not. */
1123
1124 uschar * rcpt = transport_rcpt_address(addr,
1125 addr->transport ? addr->transport->rcpt_include_affixes : FALSE);
1126
1127 #ifdef EXPERIMENTAL_INTERNATIONAL
1128 /*XXX should the conversion be moved into transport_rcpt_address() ? */
1129 uschar * dummy_errstr = NULL;
1130 if ( testflag(addr, af_utf8_downcvt)
1131 && (rcpt = string_address_utf8_to_alabel(rcpt, &dummy_errstr),
1132 dummy_errstr
1133 ) )
1134 {
1135 errno = ERRNO_EXPANDFAIL;
1136 *failure_ptr = US"recipient";
1137 done = FALSE;
1138 }
1139 else
1140 #endif
1141
1142 done =
1143 smtp_write_command(&outblock, FALSE, "RCPT TO:<%.1000s>\r\n",
1144 rcpt) >= 0 &&
1145 smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer),
1146 '2', callout);
1147
1148 if (done)
1149 new_address_record.result = ccache_accept;
1150 else if (errno == 0 && responsebuffer[0] == '5')
1151 {
1152 *failure_ptr = US"recipient";
1153 new_address_record.result = ccache_reject;
1154 }
1155
1156 /* Do postmaster check if requested; if a full check is required, we
1157 check for RCPT TO:<postmaster> (no domain) in accordance with RFC 821. */
1158
1159 if (done && pm_mailfrom != NULL)
1160 {
1161 /* Could possibly shift before main verify, just above, and be ok
1162 for cutthrough. But no way to handle a subsequent rcpt, so just
1163 refuse any */
1164 cancel_cutthrough_connection("postmaster verify");
1165 HDEBUG(D_acl|D_v) debug_printf("Cutthrough cancelled by presence of postmaster verify\n");
1166
1167 done =
1168 smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0 &&
1169 smtp_read_response(&inblock, responsebuffer,
1170 sizeof(responsebuffer), '2', callout) &&
1171
1172 smtp_write_command(&outblock, FALSE,
1173 "MAIL FROM:<%s>\r\n", pm_mailfrom) >= 0 &&
1174 smtp_read_response(&inblock, responsebuffer,
1175 sizeof(responsebuffer), '2', callout) &&
1176
1177 /* First try using the current domain */
1178
1179 ((
1180 smtp_write_command(&outblock, FALSE,
1181 "RCPT TO:<postmaster@%.1000s>\r\n", rcpt_domain) >= 0 &&
1182 smtp_read_response(&inblock, responsebuffer,
1183 sizeof(responsebuffer), '2', callout)
1184 )
1185
1186 ||
1187
1188 /* If that doesn't work, and a full check is requested,
1189 try without the domain. */
1190
1191 (
1192 (options & vopt_callout_fullpm) != 0 &&
1193 smtp_write_command(&outblock, FALSE,
1194 "RCPT TO:<postmaster>\r\n") >= 0 &&
1195 smtp_read_response(&inblock, responsebuffer,
1196 sizeof(responsebuffer), '2', callout)
1197 ));
1198
1199 /* Sort out the cache record */
1200
1201 new_domain_record.postmaster_stamp = time(NULL);
1202
1203 if (done)
1204 new_domain_record.postmaster_result = ccache_accept;
1205 else if (errno == 0 && responsebuffer[0] == '5')
1206 {
1207 *failure_ptr = US"postmaster";
1208 setflag(addr, af_verify_pmfail);
1209 new_domain_record.postmaster_result = ccache_reject;
1210 }
1211 }
1212 } /* Random not accepted */
1213 } /* MAIL FROM: accepted */
1214
1215 /* For any failure of the main check, other than a negative response, we just
1216 close the connection and carry on. We can identify a negative response by the
1217 fact that errno is zero. For I/O errors it will be non-zero
1218
1219 Set up different error texts for logging and for sending back to the caller
1220 as an SMTP response. Log in all cases, using a one-line format. For sender
1221 callouts, give a full response to the caller, but for recipient callouts,
1222 don't give the IP address because this may be an internal host whose identity
1223 is not to be widely broadcast. */
1224
1225 if (!done)
1226 {
1227 if (errno == ETIMEDOUT)
1228 {
1229 HDEBUG(D_verify) debug_printf("SMTP timeout\n");
1230 send_quit = FALSE;
1231 }
1232 #ifdef EXPERIMENTAL_INTERNATIONAL
1233 else if (errno == ERRNO_UTF8_FWD)
1234 {
1235 extern int acl_where; /* src/acl.c */
1236 errno = 0;
1237 addr->message = string_sprintf(
1238 "response to \"%s\" from %s [%s] did not include SMTPUTF8",
1239 big_buffer, host->name, host->address);
1240 addr->user_message = acl_where == ACL_WHERE_RCPT
1241 ? US"533 mailbox name not allowed"
1242 : US"550 mailbox unavailable";
1243 yield = FAIL;
1244 done = TRUE;
1245 }
1246 #endif
1247 else if (errno == 0)
1248 {
1249 if (*responsebuffer == 0) Ustrcpy(responsebuffer, US"connection dropped");
1250
1251 addr->message =
1252 string_sprintf("response to \"%s\" from %s [%s] was: %s",
1253 big_buffer, host->name, host->address,
1254 string_printing(responsebuffer));
1255
1256 addr->user_message = is_recipient?
1257 string_sprintf("Callout verification failed:\n%s", responsebuffer)
1258 :
1259 string_sprintf("Called: %s\nSent: %s\nResponse: %s",
1260 host->address, big_buffer, responsebuffer);
1261
1262 /* Hard rejection ends the process */
1263
1264 if (responsebuffer[0] == '5') /* Address rejected */
1265 {
1266 yield = FAIL;
1267 done = TRUE;
1268 }
1269 }
1270 }
1271
1272 /* End the SMTP conversation and close the connection. */
1273
1274 /* Cutthrough - on a successfull connect and recipient-verify with
1275 use-sender and we are 1st rcpt and have no cutthrough conn so far
1276 here is where we want to leave the conn open */
1277 if ( cutthrough.delivery
1278 && rcpt_count == 1
1279 && done
1280 && yield == OK
1281 && (options & (vopt_callout_recipsender|vopt_callout_recippmaster)) == vopt_callout_recipsender
1282 && !random_local_part
1283 && !pm_mailfrom
1284 && cutthrough.fd < 0
1285 && !lmtp
1286 )
1287 {
1288 cutthrough.fd = outblock.sock; /* We assume no buffer in use in the outblock */
1289 cutthrough.nrcpt = 1;
1290 cutthrough.interface = interface;
1291 cutthrough.host = *host;
1292 cutthrough.addr = *addr; /* Save the address_item for later logging */
1293 cutthrough.addr.next = NULL;
1294 cutthrough.addr.host_used = &cutthrough.host;
1295 if (addr->parent)
1296 *(cutthrough.addr.parent = store_get(sizeof(address_item))) =
1297 *addr->parent;
1298 ctblock.buffer = ctbuffer;
1299 ctblock.buffersize = sizeof(ctbuffer);
1300 ctblock.ptr = ctbuffer;
1301 /* ctblock.cmd_count = 0; ctblock.authenticating = FALSE; */
1302 ctblock.sock = cutthrough.fd;
1303 }
1304 else
1305 {
1306 /* Ensure no cutthrough on multiple address verifies */
1307 if (options & vopt_callout_recipsender)
1308 cancel_cutthrough_connection("multiple verify calls");
1309 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
1310
1311 #ifdef SUPPORT_TLS
1312 tls_close(FALSE, TRUE);
1313 #endif
1314 (void)close(inblock.sock);
1315 #ifdef EXPERIMENTAL_EVENT
1316 (void) event_raise(addr->transport->event_action,
1317 US"tcp:close", NULL);
1318 #endif
1319 }
1320
1321 } /* Loop through all hosts, while !done */
1322 }
1323
1324 /* If we get here with done == TRUE, a successful callout happened, and yield
1325 will be set OK or FAIL according to the response to the RCPT command.
1326 Otherwise, we looped through the hosts but couldn't complete the business.
1327 However, there may be domain-specific information to cache in both cases.
1328
1329 The value of the result field in the new_domain record is ccache_unknown if
1330 there was an error before or with MAIL FROM:, and errno was not zero,
1331 implying some kind of I/O error. We don't want to write the cache in that case.
1332 Otherwise the value is ccache_accept, ccache_reject, or ccache_reject_mfnull. */
1333
1334 if (!callout_no_cache && new_domain_record.result != ccache_unknown)
1335 {
1336 if ((dbm_file = dbfn_open(US"callout", O_RDWR|O_CREAT, &dbblock, FALSE))
1337 == NULL)
1338 {
1339 HDEBUG(D_verify) debug_printf("callout cache: not available\n");
1340 }
1341 else
1342 {
1343 (void)dbfn_write(dbm_file, addr->domain, &new_domain_record,
1344 (int)sizeof(dbdata_callout_cache));
1345 HDEBUG(D_verify) debug_printf("wrote callout cache domain record:\n"
1346 " result=%d postmaster=%d random=%d\n",
1347 new_domain_record.result,
1348 new_domain_record.postmaster_result,
1349 new_domain_record.random_result);
1350 }
1351 }
1352
1353 /* If a definite result was obtained for the callout, cache it unless caching
1354 is disabled. */
1355
1356 if (done)
1357 {
1358 if (!callout_no_cache && new_address_record.result != ccache_unknown)
1359 {
1360 if (dbm_file == NULL)
1361 dbm_file = dbfn_open(US"callout", O_RDWR|O_CREAT, &dbblock, FALSE);
1362 if (dbm_file == NULL)
1363 {
1364 HDEBUG(D_verify) debug_printf("no callout cache available\n");
1365 }
1366 else
1367 {
1368 (void)dbfn_write(dbm_file, address_key, &new_address_record,
1369 (int)sizeof(dbdata_callout_cache_address));
1370 HDEBUG(D_verify) debug_printf("wrote %s callout cache address record\n",
1371 (new_address_record.result == ccache_accept)? "positive" : "negative");
1372 }
1373 }
1374 } /* done */
1375
1376 /* Failure to connect to any host, or any response other than 2xx or 5xx is a
1377 temporary error. If there was only one host, and a response was received, leave
1378 it alone if supplying details. Otherwise, give a generic response. */
1379
1380 else /* !done */
1381 {
1382 uschar *dullmsg = string_sprintf("Could not complete %s verify callout",
1383 is_recipient? "recipient" : "sender");
1384 yield = DEFER;
1385
1386 if (host_list->next != NULL || addr->message == NULL) addr->message = dullmsg;
1387
1388 addr->user_message = (!smtp_return_error_details)? dullmsg :
1389 string_sprintf("%s for <%s>.\n"
1390 "The mail server(s) for the domain may be temporarily unreachable, or\n"
1391 "they may be permanently unreachable from this server. In the latter case,\n%s",
1392 dullmsg, addr->address,
1393 is_recipient?
1394 "the address will never be accepted."
1395 :
1396 "you need to change the address or create an MX record for its domain\n"
1397 "if it is supposed to be generally accessible from the Internet.\n"
1398 "Talk to your mail administrator for details.");
1399
1400 /* Force a specific error code */
1401
1402 addr->basic_errno = ERRNO_CALLOUTDEFER;
1403 }
1404
1405 /* Come here from within the cache-reading code on fast-track exit. */
1406
1407 END_CALLOUT:
1408 if (dbm_file != NULL) dbfn_close(dbm_file);
1409 return yield;
1410 }
1411
1412
1413
1414 /* Called after recipient-acl to get a cutthrough connection open when
1415 one was requested and a recipient-verify wasn't subsequently done.
1416 */
1417 void
1418 open_cutthrough_connection( address_item * addr )
1419 {
1420 address_item addr2;
1421
1422 /* Use a recipient-verify-callout to set up the cutthrough connection. */
1423 /* We must use a copy of the address for verification, because it might
1424 get rewritten. */
1425
1426 addr2 = *addr;
1427 HDEBUG(D_acl) debug_printf("----------- %s cutthrough setup ------------\n",
1428 rcpt_count > 1 ? "more" : "start");
1429 (void) verify_address(&addr2, NULL,
1430 vopt_is_recipient | vopt_callout_recipsender | vopt_callout_no_cache,
1431 CUTTHROUGH_CMD_TIMEOUT, -1, -1,
1432 NULL, NULL, NULL);
1433 HDEBUG(D_acl) debug_printf("----------- end cutthrough setup ------------\n");
1434 return;
1435 }
1436
1437
1438
1439 /* Send given number of bytes from the buffer */
1440 static BOOL
1441 cutthrough_send(int n)
1442 {
1443 if(cutthrough.fd < 0)
1444 return TRUE;
1445
1446 if(
1447 #ifdef SUPPORT_TLS
1448 (tls_out.active == cutthrough.fd) ? tls_write(FALSE, ctblock.buffer, n) :
1449 #endif
1450 send(cutthrough.fd, ctblock.buffer, n, 0) > 0
1451 )
1452 {
1453 transport_count += n;
1454 ctblock.ptr= ctblock.buffer;
1455 return TRUE;
1456 }
1457
1458 HDEBUG(D_transport|D_acl) debug_printf("cutthrough_send failed: %s\n", strerror(errno));
1459 return FALSE;
1460 }
1461
1462
1463
1464 static BOOL
1465 _cutthrough_puts(uschar * cp, int n)
1466 {
1467 while(n--)
1468 {
1469 if(ctblock.ptr >= ctblock.buffer+ctblock.buffersize)
1470 if(!cutthrough_send(ctblock.buffersize))
1471 return FALSE;
1472
1473 *ctblock.ptr++ = *cp++;
1474 }
1475 return TRUE;
1476 }
1477
1478 /* Buffered output of counted data block. Return boolean success */
1479 BOOL
1480 cutthrough_puts(uschar * cp, int n)
1481 {
1482 if (cutthrough.fd < 0) return TRUE;
1483 if (_cutthrough_puts(cp, n)) return TRUE;
1484 cancel_cutthrough_connection("transmit failed");
1485 return FALSE;
1486 }
1487
1488
1489 static BOOL
1490 _cutthrough_flush_send(void)
1491 {
1492 int n= ctblock.ptr-ctblock.buffer;
1493
1494 if(n>0)
1495 if(!cutthrough_send(n))
1496 return FALSE;
1497 return TRUE;
1498 }
1499
1500
1501 /* Send out any bufferred output. Return boolean success. */
1502 BOOL
1503 cutthrough_flush_send(void)
1504 {
1505 if (_cutthrough_flush_send()) return TRUE;
1506 cancel_cutthrough_connection("transmit failed");
1507 return FALSE;
1508 }
1509
1510
1511 BOOL
1512 cutthrough_put_nl(void)
1513 {
1514 return cutthrough_puts(US"\r\n", 2);
1515 }
1516
1517
1518 /* Get and check response from cutthrough target */
1519 static uschar
1520 cutthrough_response(char expect, uschar ** copy)
1521 {
1522 smtp_inblock inblock;
1523 uschar inbuffer[4096];
1524 uschar responsebuffer[4096];
1525
1526 inblock.buffer = inbuffer;
1527 inblock.buffersize = sizeof(inbuffer);
1528 inblock.ptr = inbuffer;
1529 inblock.ptrend = inbuffer;
1530 inblock.sock = cutthrough.fd;
1531 /* this relies on (inblock.sock == tls_out.active) */
1532 if(!smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer), expect, CUTTHROUGH_DATA_TIMEOUT))
1533 cancel_cutthrough_connection("target timeout on read");
1534
1535 if(copy != NULL)
1536 {
1537 uschar * cp;
1538 *copy = cp = string_copy(responsebuffer);
1539 /* Trim the trailing end of line */
1540 cp += Ustrlen(responsebuffer);
1541 if(cp > *copy && cp[-1] == '\n') *--cp = '\0';
1542 if(cp > *copy && cp[-1] == '\r') *--cp = '\0';
1543 }
1544
1545 return responsebuffer[0];
1546 }
1547
1548
1549 /* Negotiate dataphase with the cutthrough target, returning success boolean */
1550 BOOL
1551 cutthrough_predata(void)
1552 {
1553 if(cutthrough.fd < 0)
1554 return FALSE;
1555
1556 HDEBUG(D_transport|D_acl|D_v) debug_printf(" SMTP>> DATA\n");
1557 cutthrough_puts(US"DATA\r\n", 6);
1558 cutthrough_flush_send();
1559
1560 /* Assume nothing buffered. If it was it gets ignored. */
1561 return cutthrough_response('3', NULL) == '3';
1562 }
1563
1564
1565 /* fd and use_crlf args only to match write_chunk() */
1566 static BOOL
1567 cutthrough_write_chunk(int fd, uschar * s, int len, BOOL use_crlf)
1568 {
1569 uschar * s2;
1570 while(s && (s2 = Ustrchr(s, '\n')))
1571 {
1572 if(!cutthrough_puts(s, s2-s) || !cutthrough_put_nl())
1573 return FALSE;
1574 s = s2+1;
1575 }
1576 return TRUE;
1577 }
1578
1579
1580 /* Buffered send of headers. Return success boolean. */
1581 /* Expands newlines to wire format (CR,NL). */
1582 /* Also sends header-terminating blank line. */
1583 BOOL
1584 cutthrough_headers_send(void)
1585 {
1586 if(cutthrough.fd < 0)
1587 return FALSE;
1588
1589 /* We share a routine with the mainline transport to handle header add/remove/rewrites,
1590 but having a separate buffered-output function (for now)
1591 */
1592 HDEBUG(D_acl) debug_printf("----------- start cutthrough headers send -----------\n");
1593
1594 if (!transport_headers_send(&cutthrough.addr, cutthrough.fd,
1595 cutthrough.addr.transport->add_headers,
1596 cutthrough.addr.transport->remove_headers,
1597 &cutthrough_write_chunk, TRUE,
1598 cutthrough.addr.transport->rewrite_rules,
1599 cutthrough.addr.transport->rewrite_existflags))
1600 return FALSE;
1601
1602 HDEBUG(D_acl) debug_printf("----------- done cutthrough headers send ------------\n");
1603 return TRUE;
1604 }
1605
1606
1607 static void
1608 close_cutthrough_connection(const char * why)
1609 {
1610 if(cutthrough.fd >= 0)
1611 {
1612 /* We could be sending this after a bunch of data, but that is ok as
1613 the only way to cancel the transfer in dataphase is to drop the tcp
1614 conn before the final dot.
1615 */
1616 ctblock.ptr = ctbuffer;
1617 HDEBUG(D_transport|D_acl|D_v) debug_printf(" SMTP>> QUIT\n");
1618 _cutthrough_puts(US"QUIT\r\n", 6); /* avoid recursion */
1619 _cutthrough_flush_send();
1620 /* No wait for response */
1621
1622 #ifdef SUPPORT_TLS
1623 tls_close(FALSE, TRUE);
1624 #endif
1625 (void)close(cutthrough.fd);
1626 cutthrough.fd = -1;
1627 HDEBUG(D_acl) debug_printf("----------- cutthrough shutdown (%s) ------------\n", why);
1628 }
1629 ctblock.ptr = ctbuffer;
1630 }
1631
1632 void
1633 cancel_cutthrough_connection(const char * why)
1634 {
1635 close_cutthrough_connection(why);
1636 cutthrough.delivery = FALSE;
1637 }
1638
1639
1640
1641
1642 /* Have senders final-dot. Send one to cutthrough target, and grab the response.
1643 Log an OK response as a transmission.
1644 Close the connection.
1645 Return smtp response-class digit.
1646 */
1647 uschar *
1648 cutthrough_finaldot(void)
1649 {
1650 uschar res;
1651 address_item * addr;
1652 HDEBUG(D_transport|D_acl|D_v) debug_printf(" SMTP>> .\n");
1653
1654 /* Assume data finshed with new-line */
1655 if( !cutthrough_puts(US".", 1)
1656 || !cutthrough_put_nl()
1657 || !cutthrough_flush_send()
1658 )
1659 return cutthrough.addr.message;
1660
1661 res = cutthrough_response('2', &cutthrough.addr.message);
1662 for (addr = &cutthrough.addr; addr; addr = addr->next)
1663 {
1664 addr->message = cutthrough.addr.message;
1665 switch(res)
1666 {
1667 case '2':
1668 delivery_log(LOG_MAIN, addr, (int)'>', NULL);
1669 close_cutthrough_connection("delivered");
1670 break;
1671
1672 case '4':
1673 delivery_log(LOG_MAIN, addr, 0,
1674 US"tmp-reject from cutthrough after DATA:");
1675 break;
1676
1677 case '5':
1678 delivery_log(LOG_MAIN|LOG_REJECT, addr, 0,
1679 US"rejected after DATA:");
1680 break;
1681
1682 default:
1683 break;
1684 }
1685 }
1686 return cutthrough.addr.message;
1687 }
1688
1689
1690
1691 /*************************************************
1692 * Copy error to toplevel address *
1693 *************************************************/
1694
1695 /* This function is used when a verify fails or defers, to ensure that the
1696 failure or defer information is in the original toplevel address. This applies
1697 when an address is redirected to a single new address, and the failure or
1698 deferral happens to the child address.
1699
1700 Arguments:
1701 vaddr the verify address item
1702 addr the final address item
1703 yield FAIL or DEFER
1704
1705 Returns: the value of YIELD
1706 */
1707
1708 static int
1709 copy_error(address_item *vaddr, address_item *addr, int yield)
1710 {
1711 if (addr != vaddr)
1712 {
1713 vaddr->message = addr->message;
1714 vaddr->user_message = addr->user_message;
1715 vaddr->basic_errno = addr->basic_errno;
1716 vaddr->more_errno = addr->more_errno;
1717 vaddr->prop.address_data = addr->prop.address_data;
1718 copyflag(vaddr, addr, af_pass_message);
1719 }
1720 return yield;
1721 }
1722
1723
1724
1725
1726 /**************************************************
1727 * printf that automatically handles TLS if needed *
1728 ***************************************************/
1729
1730 /* This function is used by verify_address() as a substitute for all fprintf()
1731 calls; a direct fprintf() will not produce output in a TLS SMTP session, such
1732 as a response to an EXPN command. smtp_in.c makes smtp_printf available but
1733 that assumes that we always use the smtp_out FILE* when not using TLS or the
1734 ssl buffer when we are. Instead we take a FILE* parameter and check to see if
1735 that is smtp_out; if so, smtp_printf() with TLS support, otherwise regular
1736 fprintf().
1737
1738 Arguments:
1739 f the candidate FILE* to write to
1740 format format string
1741 ... optional arguments
1742
1743 Returns:
1744 nothing
1745 */
1746
1747 static void PRINTF_FUNCTION(2,3)
1748 respond_printf(FILE *f, const char *format, ...)
1749 {
1750 va_list ap;
1751
1752 va_start(ap, format);
1753 if (smtp_out && (f == smtp_out))
1754 smtp_vprintf(format, ap);
1755 else
1756 vfprintf(f, format, ap);
1757 va_end(ap);
1758 }
1759
1760
1761
1762 /*************************************************
1763 * Verify an email address *
1764 *************************************************/
1765
1766 /* This function is used both for verification (-bv and at other times) and
1767 address testing (-bt), which is indicated by address_test_mode being set.
1768
1769 Arguments:
1770 vaddr contains the address to verify; the next field in this block
1771 must be NULL
1772 f if not NULL, write the result to this file
1773 options various option bits:
1774 vopt_fake_sender => this sender verify is not for the real
1775 sender (it was verify=sender=xxxx or an address from a
1776 header line) - rewriting must not change sender_address
1777 vopt_is_recipient => this is a recipient address, otherwise
1778 it's a sender address - this affects qualification and
1779 rewriting and messages from callouts
1780 vopt_qualify => qualify an unqualified address; else error
1781 vopt_expn => called from SMTP EXPN command
1782 vopt_success_on_redirect => when a new address is generated
1783 the verification instantly succeeds
1784
1785 These ones are used by do_callout() -- the options variable
1786 is passed to it.
1787
1788 vopt_callout_fullpm => if postmaster check, do full one
1789 vopt_callout_no_cache => don't use callout cache
1790 vopt_callout_random => do the "random" thing
1791 vopt_callout_recipsender => use real sender for recipient
1792 vopt_callout_recippmaster => use postmaster for recipient
1793
1794 callout if > 0, specifies that callout is required, and gives timeout
1795 for individual commands
1796 callout_overall if > 0, gives overall timeout for the callout function;
1797 if < 0, a default is used (see do_callout())
1798 callout_connect the connection timeout for callouts
1799 se_mailfrom when callout is requested to verify a sender, use this
1800 in MAIL FROM; NULL => ""
1801 pm_mailfrom when callout is requested, if non-NULL, do the postmaster
1802 thing and use this as the sender address (may be "")
1803
1804 routed if not NULL, set TRUE if routing succeeded, so we can
1805 distinguish between routing failed and callout failed
1806
1807 Returns: OK address verified
1808 FAIL address failed to verify
1809 DEFER can't tell at present
1810 */
1811
1812 int
1813 verify_address(address_item *vaddr, FILE *f, int options, int callout,
1814 int callout_overall, int callout_connect, uschar *se_mailfrom,
1815 uschar *pm_mailfrom, BOOL *routed)
1816 {
1817 BOOL allok = TRUE;
1818 BOOL full_info = (f == NULL)? FALSE : (debug_selector != 0);
1819 BOOL is_recipient = (options & vopt_is_recipient) != 0;
1820 BOOL expn = (options & vopt_expn) != 0;
1821 BOOL success_on_redirect = (options & vopt_success_on_redirect) != 0;
1822 int i;
1823 int yield = OK;
1824 int verify_type = expn? v_expn :
1825 address_test_mode? v_none :
1826 is_recipient? v_recipient : v_sender;
1827 address_item *addr_list;
1828 address_item *addr_new = NULL;
1829 address_item *addr_remote = NULL;
1830 address_item *addr_local = NULL;
1831 address_item *addr_succeed = NULL;
1832 uschar **failure_ptr = is_recipient?
1833 &recipient_verify_failure : &sender_verify_failure;
1834 uschar *ko_prefix, *cr;
1835 uschar *address = vaddr->address;
1836 uschar *save_sender;
1837 uschar null_sender[] = { 0 }; /* Ensure writeable memory */
1838
1839 /* Clear, just in case */
1840
1841 *failure_ptr = NULL;
1842
1843 /* Set up a prefix and suffix for error message which allow us to use the same
1844 output statements both in EXPN mode (where an SMTP response is needed) and when
1845 debugging with an output file. */
1846
1847 if (expn)
1848 {
1849 ko_prefix = US"553 ";
1850 cr = US"\r";
1851 }
1852 else ko_prefix = cr = US"";
1853
1854 /* Add qualify domain if permitted; otherwise an unqualified address fails. */
1855
1856 if (parse_find_at(address) == NULL)
1857 {
1858 if ((options & vopt_qualify) == 0)
1859 {
1860 if (f != NULL)
1861 respond_printf(f, "%sA domain is required for \"%s\"%s\n",
1862 ko_prefix, address, cr);
1863 *failure_ptr = US"qualify";
1864 return FAIL;
1865 }
1866 address = rewrite_address_qualify(address, is_recipient);
1867 }
1868
1869 DEBUG(D_verify)
1870 {
1871 debug_printf(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
1872 debug_printf("%s %s\n", address_test_mode? "Testing" : "Verifying", address);
1873 }
1874
1875 /* Rewrite and report on it. Clear the domain and local part caches - these
1876 may have been set by domains and local part tests during an ACL. */
1877
1878 if (global_rewrite_rules != NULL)
1879 {
1880 uschar *old = address;
1881 address = rewrite_address(address, is_recipient, FALSE,
1882 global_rewrite_rules, rewrite_existflags);
1883 if (address != old)
1884 {
1885 for (i = 0; i < (MAX_NAMED_LIST * 2)/32; i++) vaddr->localpart_cache[i] = 0;
1886 for (i = 0; i < (MAX_NAMED_LIST * 2)/32; i++) vaddr->domain_cache[i] = 0;
1887 if (f != NULL && !expn) fprintf(f, "Address rewritten as: %s\n", address);
1888 }
1889 }
1890
1891 /* If this is the real sender address, we must update sender_address at
1892 this point, because it may be referred to in the routers. */
1893
1894 if ((options & (vopt_fake_sender|vopt_is_recipient)) == 0)
1895 sender_address = address;
1896
1897 /* If the address was rewritten to <> no verification can be done, and we have
1898 to return OK. This rewriting is permitted only for sender addresses; for other
1899 addresses, such rewriting fails. */
1900
1901 if (address[0] == 0) return OK;
1902
1903 /* Flip the legacy TLS-related variables over to the outbound set in case
1904 they're used in the context of a transport used by verification. Reset them
1905 at exit from this routine. */
1906
1907 tls_modify_variables(&tls_out);
1908
1909 /* Save a copy of the sender address for re-instating if we change it to <>
1910 while verifying a sender address (a nice bit of self-reference there). */
1911
1912 save_sender = sender_address;
1913
1914 /* Update the address structure with the possibly qualified and rewritten
1915 address. Set it up as the starting address on the chain of new addresses. */
1916
1917 vaddr->address = address;
1918 addr_new = vaddr;
1919
1920 /* We need a loop, because an address can generate new addresses. We must also
1921 cope with generated pipes and files at the top level. (See also the code and
1922 comment in deliver.c.) However, it is usually the case that the router for
1923 user's .forward files has its verify flag turned off.
1924
1925 If an address generates more than one child, the loop is used only when
1926 full_info is set, and this can only be set locally. Remote enquiries just get
1927 information about the top level address, not anything that it generated. */
1928
1929 while (addr_new != NULL)
1930 {
1931 int rc;
1932 address_item *addr = addr_new;
1933
1934 addr_new = addr->next;
1935 addr->next = NULL;
1936
1937 DEBUG(D_verify)
1938 {
1939 debug_printf(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
1940 debug_printf("Considering %s\n", addr->address);
1941 }
1942
1943 /* Handle generated pipe, file or reply addresses. We don't get these
1944 when handling EXPN, as it does only one level of expansion. */
1945
1946 if (testflag(addr, af_pfr))
1947 {
1948 allok = FALSE;
1949 if (f != NULL)
1950 {
1951 BOOL allow;
1952
1953 if (addr->address[0] == '>')
1954 {
1955 allow = testflag(addr, af_allow_reply);
1956 fprintf(f, "%s -> mail %s", addr->parent->address, addr->address + 1);
1957 }
1958 else
1959 {
1960 allow = (addr->address[0] == '|')?
1961 testflag(addr, af_allow_pipe) : testflag(addr, af_allow_file);
1962 fprintf(f, "%s -> %s", addr->parent->address, addr->address);
1963 }
1964
1965 if (addr->basic_errno == ERRNO_BADTRANSPORT)
1966 fprintf(f, "\n*** Error in setting up pipe, file, or autoreply:\n"
1967 "%s\n", addr->message);
1968 else if (allow)
1969 fprintf(f, "\n transport = %s\n", addr->transport->name);
1970 else
1971 fprintf(f, " *** forbidden ***\n");
1972 }
1973 continue;
1974 }
1975
1976 /* Just in case some router parameter refers to it. */
1977
1978 return_path = (addr->prop.errors_address != NULL)?
1979 addr->prop.errors_address : sender_address;
1980
1981 /* Split the address into domain and local part, handling the %-hack if
1982 necessary, and then route it. While routing a sender address, set
1983 $sender_address to <> because that is what it will be if we were trying to
1984 send a bounce to the sender. */
1985
1986 if (routed != NULL) *routed = FALSE;
1987 if ((rc = deliver_split_address(addr)) == OK)
1988 {
1989 if (!is_recipient) sender_address = null_sender;
1990 rc = route_address(addr, &addr_local, &addr_remote, &addr_new,
1991 &addr_succeed, verify_type);
1992 sender_address = save_sender; /* Put back the real sender */
1993 }
1994
1995 /* If routing an address succeeded, set the flag that remembers, for use when
1996 an ACL cached a sender verify (in case a callout fails). Then if routing set
1997 up a list of hosts or the transport has a host list, and the callout option
1998 is set, and we aren't in a host checking run, do the callout verification,
1999 and set another flag that notes that a callout happened. */
2000
2001 if (rc == OK)
2002 {
2003 if (routed != NULL) *routed = TRUE;
2004 if (callout > 0)
2005 {
2006 host_item *host_list = addr->host_list;
2007
2008 /* Make up some data for use in the case where there is no remote
2009 transport. */
2010
2011 transport_feedback tf = {
2012 NULL, /* interface (=> any) */
2013 US"smtp", /* port */
2014 US"smtp", /* protocol */
2015 NULL, /* hosts */
2016 US"$smtp_active_hostname", /* helo_data */
2017 FALSE, /* hosts_override */
2018 FALSE, /* hosts_randomize */
2019 FALSE, /* gethostbyname */
2020 TRUE, /* qualify_single */
2021 FALSE /* search_parents */
2022 };
2023
2024 /* If verification yielded a remote transport, we want to use that
2025 transport's options, so as to mimic what would happen if we were really
2026 sending a message to this address. */
2027
2028 if (addr->transport != NULL && !addr->transport->info->local)
2029 {
2030 (void)(addr->transport->setup)(addr->transport, addr, &tf, 0, 0, NULL);
2031
2032 /* If the transport has hosts and the router does not, or if the
2033 transport is configured to override the router's hosts, we must build a
2034 host list of the transport's hosts, and find the IP addresses */
2035
2036 if (tf.hosts != NULL && (host_list == NULL || tf.hosts_override))
2037 {
2038 uschar *s;
2039 const uschar *save_deliver_domain = deliver_domain;
2040 uschar *save_deliver_localpart = deliver_localpart;
2041
2042 host_list = NULL; /* Ignore the router's hosts */
2043
2044 deliver_domain = addr->domain;
2045 deliver_localpart = addr->local_part;
2046 s = expand_string(tf.hosts);
2047 deliver_domain = save_deliver_domain;
2048 deliver_localpart = save_deliver_localpart;
2049
2050 if (s == NULL)
2051 {
2052 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand list of hosts "
2053 "\"%s\" in %s transport for callout: %s", tf.hosts,
2054 addr->transport->name, expand_string_message);
2055 }
2056 else
2057 {
2058 int flags;
2059 host_item *host, *nexthost;
2060 host_build_hostlist(&host_list, s, tf.hosts_randomize);
2061
2062 /* Just ignore failures to find a host address. If we don't manage
2063 to find any addresses, the callout will defer. Note that more than
2064 one address may be found for a single host, which will result in
2065 additional host items being inserted into the chain. Hence we must
2066 save the next host first. */
2067
2068 flags = HOST_FIND_BY_A;
2069 if (tf.qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
2070 if (tf.search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
2071
2072 for (host = host_list; host != NULL; host = nexthost)
2073 {
2074 nexthost = host->next;
2075 if (tf.gethostbyname ||
2076 string_is_ip_address(host->name, NULL) != 0)
2077 (void)host_find_byname(host, NULL, flags, NULL, TRUE);
2078 else
2079 {
2080 dnssec_domains * dnssec_domains = NULL;
2081 if (Ustrcmp(addr->transport->driver_name, "smtp") == 0)
2082 {
2083 smtp_transport_options_block * ob =
2084 (smtp_transport_options_block *)
2085 addr->transport->options_block;
2086 dnssec_domains = &ob->dnssec;
2087 }
2088
2089 (void)host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
2090 dnssec_domains, NULL, NULL);
2091 }
2092 }
2093 }
2094 }
2095 }
2096
2097 /* Can only do a callout if we have at least one host! If the callout
2098 fails, it will have set ${sender,recipient}_verify_failure. */
2099
2100 if (host_list != NULL)
2101 {
2102 HDEBUG(D_verify) debug_printf("Attempting full verification using callout\n");
2103 if (host_checking && !host_checking_callout)
2104 {
2105 HDEBUG(D_verify)
2106 debug_printf("... callout omitted by default when host testing\n"
2107 "(Use -bhc if you want the callouts to happen.)\n");
2108 }
2109 else
2110 {
2111 #ifdef SUPPORT_TLS
2112 deliver_set_expansions(addr);
2113 #endif
2114 verify_mode = is_recipient ? US"R" : US"S";
2115 rc = do_callout(addr, host_list, &tf, callout, callout_overall,
2116 callout_connect, options, se_mailfrom, pm_mailfrom);
2117 verify_mode = NULL;
2118 }
2119 }
2120 else
2121 {
2122 HDEBUG(D_verify) debug_printf("Cannot do callout: neither router nor "
2123 "transport provided a host list\n");
2124 }
2125 }
2126 }
2127
2128 /* Otherwise, any failure is a routing failure */
2129
2130 else *failure_ptr = US"route";
2131
2132 /* A router may return REROUTED if it has set up a child address as a result
2133 of a change of domain name (typically from widening). In this case we always
2134 want to continue to verify the new child. */
2135
2136 if (rc == REROUTED) continue;
2137
2138 /* Handle hard failures */
2139
2140 if (rc == FAIL)
2141 {
2142 allok = FALSE;
2143 if (f != NULL)
2144 {
2145 address_item *p = addr->parent;
2146
2147 respond_printf(f, "%s%s %s", ko_prefix,
2148 full_info? addr->address : address,
2149 address_test_mode? "is undeliverable" : "failed to verify");
2150 if (!expn && admin_user)
2151 {
2152 if (addr->basic_errno > 0)
2153 respond_printf(f, ": %s", strerror(addr->basic_errno));
2154 if (addr->message != NULL)
2155 respond_printf(f, ": %s", addr->message);
2156 }
2157
2158 /* Show parents iff doing full info */
2159
2160 if (full_info) while (p != NULL)
2161 {
2162 respond_printf(f, "%s\n <-- %s", cr, p->address);
2163 p = p->parent;
2164 }
2165 respond_printf(f, "%s\n", cr);
2166 }
2167 cancel_cutthrough_connection("routing hard fail");
2168
2169 if (!full_info)
2170 {
2171 yield = copy_error(vaddr, addr, FAIL);
2172 goto out;
2173 }
2174 else yield = FAIL;
2175 }
2176
2177 /* Soft failure */
2178
2179 else if (rc == DEFER)
2180 {
2181 allok = FALSE;
2182 if (f != NULL)
2183 {
2184 address_item *p = addr->parent;
2185 respond_printf(f, "%s%s cannot be resolved at this time", ko_prefix,
2186 full_info? addr->address : address);
2187 if (!expn && admin_user)
2188 {
2189 if (addr->basic_errno > 0)
2190 respond_printf(f, ": %s", strerror(addr->basic_errno));
2191 if (addr->message != NULL)
2192 respond_printf(f, ": %s", addr->message);
2193 else if (addr->basic_errno <= 0)
2194 respond_printf(f, ": unknown error");
2195 }
2196
2197 /* Show parents iff doing full info */
2198
2199 if (full_info) while (p != NULL)
2200 {
2201 respond_printf(f, "%s\n <-- %s", cr, p->address);
2202 p = p->parent;
2203 }
2204 respond_printf(f, "%s\n", cr);
2205 }
2206 cancel_cutthrough_connection("routing soft fail");
2207
2208 if (!full_info)
2209 {
2210 yield = copy_error(vaddr, addr, DEFER);
2211 goto out;
2212 }
2213 else if (yield == OK) yield = DEFER;
2214 }
2215
2216 /* If we are handling EXPN, we do not want to continue to route beyond
2217 the top level (whose address is in "address"). */
2218
2219 else if (expn)
2220 {
2221 uschar *ok_prefix = US"250-";
2222 if (addr_new == NULL)
2223 {
2224 if (addr_local == NULL && addr_remote == NULL)
2225 respond_printf(f, "250 mail to <%s> is discarded\r\n", address);
2226 else
2227 respond_printf(f, "250 <%s>\r\n", address);
2228 }
2229 else while (addr_new != NULL)
2230 {
2231 address_item *addr2 = addr_new;
2232 addr_new = addr2->next;
2233 if (addr_new == NULL) ok_prefix = US"250 ";
2234 respond_printf(f, "%s<%s>\r\n", ok_prefix, addr2->address);
2235 }
2236 yield = OK;
2237 goto out;
2238 }
2239
2240 /* Successful routing other than EXPN. */
2241
2242 else
2243 {
2244 /* Handle successful routing when short info wanted. Otherwise continue for
2245 other (generated) addresses. Short info is the operational case. Full info
2246 can be requested only when debug_selector != 0 and a file is supplied.
2247
2248 There is a conflict between the use of aliasing as an alternate email
2249 address, and as a sort of mailing list. If an alias turns the incoming
2250 address into just one address (e.g. J.Caesar->jc44) you may well want to
2251 carry on verifying the generated address to ensure it is valid when
2252 checking incoming mail. If aliasing generates multiple addresses, you
2253 probably don't want to do this. Exim therefore treats the generation of
2254 just a single new address as a special case, and continues on to verify the
2255 generated address. */
2256
2257 if (!full_info && /* Stop if short info wanted AND */
2258 (((addr_new == NULL || /* No new address OR */
2259 addr_new->next != NULL || /* More than one new address OR */
2260 testflag(addr_new, af_pfr))) /* New address is pfr */
2261 || /* OR */
2262 (addr_new != NULL && /* At least one new address AND */
2263 success_on_redirect))) /* success_on_redirect is set */
2264 {
2265 if (f != NULL) fprintf(f, "%s %s\n", address,
2266 address_test_mode? "is deliverable" : "verified");
2267
2268 /* If we have carried on to verify a child address, we want the value
2269 of $address_data to be that of the child */
2270
2271 vaddr->prop.address_data = addr->prop.address_data;
2272 yield = OK;
2273 goto out;
2274 }
2275 }
2276 } /* Loop for generated addresses */
2277
2278 /* Display the full results of the successful routing, including any generated
2279 addresses. Control gets here only when full_info is set, which requires f not
2280 to be NULL, and this occurs only when a top-level verify is called with the
2281 debugging switch on.
2282
2283 If there are no local and no remote addresses, and there were no pipes, files,
2284 or autoreplies, and there were no errors or deferments, the message is to be
2285 discarded, usually because of the use of :blackhole: in an alias file. */
2286
2287 if (allok && addr_local == NULL && addr_remote == NULL)
2288 {
2289 fprintf(f, "mail to %s is discarded\n", address);
2290 goto out;
2291 }
2292
2293 for (addr_list = addr_local, i = 0; i < 2; addr_list = addr_remote, i++)
2294 {
2295 while (addr_list != NULL)
2296 {
2297 address_item *addr = addr_list;
2298 address_item *p = addr->parent;
2299 addr_list = addr->next;
2300
2301 fprintf(f, "%s", CS addr->address);
2302 #ifdef EXPERIMENTAL_SRS
2303 if(addr->prop.srs_sender)
2304 fprintf(f, " [srs = %s]", addr->prop.srs_sender);
2305 #endif
2306
2307 /* If the address is a duplicate, show something about it. */
2308
2309 if (!testflag(addr, af_pfr))
2310 {
2311 tree_node *tnode;
2312 if ((tnode = tree_search(tree_duplicates, addr->unique)) != NULL)
2313 fprintf(f, " [duplicate, would not be delivered]");
2314 else tree_add_duplicate(addr->unique, addr);
2315 }
2316
2317 /* Now show its parents */
2318
2319 while (p != NULL)
2320 {
2321 fprintf(f, "\n <-- %s", p->address);
2322 p = p->parent;
2323 }
2324 fprintf(f, "\n ");
2325
2326 /* Show router, and transport */
2327
2328 fprintf(f, "router = %s, ", addr->router->name);
2329 fprintf(f, "transport = %s\n", (addr->transport == NULL)? US"unset" :
2330 addr->transport->name);
2331
2332 /* Show any hosts that are set up by a router unless the transport
2333 is going to override them; fiddle a bit to get a nice format. */
2334
2335 if (addr->host_list != NULL && addr->transport != NULL &&
2336 !addr->transport->overrides_hosts)
2337 {
2338 host_item *h;
2339 int maxlen = 0;
2340 int maxaddlen = 0;
2341 for (h = addr->host_list; h != NULL; h = h->next)
2342 {
2343 int len = Ustrlen(h->name);
2344 if (len > maxlen) maxlen = len;
2345 len = (h->address != NULL)? Ustrlen(h->address) : 7;
2346 if (len > maxaddlen) maxaddlen = len;
2347 }
2348 for (h = addr->host_list; h != NULL; h = h->next)
2349 {
2350 int len = Ustrlen(h->name);
2351 fprintf(f, " host %s ", h->name);
2352 while (len++ < maxlen) fprintf(f, " ");
2353 if (h->address != NULL)
2354 {
2355 fprintf(f, "[%s] ", h->address);
2356 len = Ustrlen(h->address);
2357 }
2358 else if (!addr->transport->info->local) /* Omit [unknown] for local */
2359 {
2360 fprintf(f, "[unknown] ");
2361 len = 7;
2362 }
2363 else len = -3;
2364 while (len++ < maxaddlen) fprintf(f," ");
2365 if (h->mx >= 0) fprintf(f, "MX=%d", h->mx);
2366 if (h->port != PORT_NONE) fprintf(f, " port=%d", h->port);
2367 if (running_in_test_harness)
2368 #ifndef DISABLE_DNSSEC
2369 fprintf(f, " ad=%s", h->dnssec==DS_YES ? "yes" : "no");
2370 #else
2371 fprintf(f, " ad=no");
2372 #endif
2373 if (h->status == hstatus_unusable) fprintf(f, " ** unusable **");
2374 fprintf(f, "\n");
2375 }
2376 }
2377 }
2378 }
2379
2380 /* Yield will be DEFER or FAIL if any one address has, only for full_info (which is
2381 the -bv or -bt case). */
2382
2383 out:
2384 tls_modify_variables(&tls_in);
2385
2386 return yield;
2387 }
2388
2389
2390
2391
2392 /*************************************************
2393 * Check headers for syntax errors *
2394 *************************************************/
2395
2396 /* This function checks those header lines that contain addresses, and verifies
2397 that all the addresses therein are syntactially correct.
2398
2399 Arguments:
2400 msgptr where to put an error message
2401
2402 Returns: OK
2403 FAIL
2404 */
2405
2406 int
2407 verify_check_headers(uschar **msgptr)
2408 {
2409 header_line *h;
2410 uschar *colon, *s;
2411 int yield = OK;
2412
2413 for (h = header_list; h != NULL && yield == OK; h = h->next)
2414 {
2415 if (h->type != htype_from &&
2416 h->type != htype_reply_to &&
2417 h->type != htype_sender &&
2418 h->type != htype_to &&
2419 h->type != htype_cc &&
2420 h->type != htype_bcc)
2421 continue;
2422
2423 colon = Ustrchr(h->text, ':');
2424 s = colon + 1;
2425 while (isspace(*s)) s++;
2426
2427 /* Loop for multiple addresses in the header, enabling group syntax. Note
2428 that we have to reset this after the header has been scanned. */
2429
2430 parse_allow_group = TRUE;
2431
2432 while (*s != 0)
2433 {
2434 uschar *ss = parse_find_address_end(s, FALSE);
2435 uschar *recipient, *errmess;
2436 int terminator = *ss;
2437 int start, end, domain;
2438
2439 /* Temporarily terminate the string at this point, and extract the
2440 operative address within, allowing group syntax. */
2441
2442 *ss = 0;
2443 recipient = parse_extract_address(s,&errmess,&start,&end,&domain,FALSE);
2444 *ss = terminator;
2445
2446 /* Permit an unqualified address only if the message is local, or if the
2447 sending host is configured to be permitted to send them. */
2448
2449 if (recipient != NULL && domain == 0)
2450 {
2451 if (h->type == htype_from || h->type == htype_sender)
2452 {
2453 if (!allow_unqualified_sender) recipient = NULL;
2454 }
2455 else
2456 {
2457 if (!allow_unqualified_recipient) recipient = NULL;
2458 }
2459 if (recipient == NULL) errmess = US"unqualified address not permitted";
2460 }
2461
2462 /* It's an error if no address could be extracted, except for the special
2463 case of an empty address. */
2464
2465 if (recipient == NULL && Ustrcmp(errmess, "empty address") != 0)
2466 {
2467 uschar *verb = US"is";
2468 uschar *t = ss;
2469 uschar *tt = colon;
2470 int len;
2471
2472 /* Arrange not to include any white space at the end in the
2473 error message or the header name. */
2474
2475 while (t > s && isspace(t[-1])) t--;
2476 while (tt > h->text && isspace(tt[-1])) tt--;
2477
2478 /* Add the address that failed to the error message, since in a
2479 header with very many addresses it is sometimes hard to spot
2480 which one is at fault. However, limit the amount of address to
2481 quote - cases have been seen where, for example, a missing double
2482 quote in a humungous To: header creates an "address" that is longer
2483 than string_sprintf can handle. */
2484
2485 len = t - s;
2486 if (len > 1024)
2487 {
2488 len = 1024;
2489 verb = US"begins";
2490 }
2491
2492 /* deconst cast ok as we're passing a non-const to string_printing() */
2493 *msgptr = US string_printing(
2494 string_sprintf("%s: failing address in \"%.*s:\" header %s: %.*s",
2495 errmess, tt - h->text, h->text, verb, len, s));
2496
2497 yield = FAIL;
2498 break; /* Out of address loop */
2499 }
2500
2501 /* Advance to the next address */
2502
2503 s = ss + (terminator? 1:0);
2504 while (isspace(*s)) s++;
2505 } /* Next address */
2506
2507 parse_allow_group = FALSE;
2508 parse_found_group = FALSE;
2509 } /* Next header unless yield has been set FALSE */
2510
2511 return yield;
2512 }
2513
2514
2515 /*************************************************
2516 * Check header names for 8-bit characters *
2517 *************************************************/
2518
2519 /* This function checks for invalid charcters in header names. See
2520 RFC 5322, 2.2. and RFC 6532, 3.
2521
2522 Arguments:
2523 msgptr where to put an error message
2524
2525 Returns: OK
2526 FAIL
2527 */
2528
2529 int
2530 verify_check_header_names_ascii(uschar **msgptr)
2531 {
2532 header_line *h;
2533 uschar *colon, *s;
2534
2535 for (h = header_list; h != NULL; h = h->next)
2536 {
2537 colon = Ustrchr(h->text, ':');
2538 for(s = h->text; s < colon; s++)
2539 {
2540 if ((*s < 33) || (*s > 126))
2541 {
2542 *msgptr = string_sprintf("Invalid character in header \"%.*s\" found",
2543 colon - h->text, h->text);
2544 return FAIL;
2545 }
2546 }
2547 }
2548 return OK;
2549 }
2550
2551 /*************************************************
2552 * Check for blind recipients *
2553 *************************************************/
2554
2555 /* This function checks that every (envelope) recipient is mentioned in either
2556 the To: or Cc: header lines, thus detecting blind carbon copies.
2557
2558 There are two ways of scanning that could be used: either scan the header lines
2559 and tick off the recipients, or scan the recipients and check the header lines.
2560 The original proposed patch did the former, but I have chosen to do the latter,
2561 because (a) it requires no memory and (b) will use fewer resources when there
2562 are many addresses in To: and/or Cc: and only one or two envelope recipients.
2563
2564 Arguments: none
2565 Returns: OK if there are no blind recipients
2566 FAIL if there is at least one blind recipient
2567 */
2568
2569 int
2570 verify_check_notblind(void)
2571 {
2572 int i;
2573 for (i = 0; i < recipients_count; i++)
2574 {
2575 header_line *h;
2576 BOOL found = FALSE;
2577 uschar *address = recipients_list[i].address;
2578
2579 for (h = header_list; !found && h != NULL; h = h->next)
2580 {
2581 uschar *colon, *s;
2582
2583 if (h->type != htype_to && h->type != htype_cc) continue;
2584
2585 colon = Ustrchr(h->text, ':');
2586 s = colon + 1;
2587 while (isspace(*s)) s++;
2588
2589 /* Loop for multiple addresses in the header, enabling group syntax. Note
2590 that we have to reset this after the header has been scanned. */
2591
2592 parse_allow_group = TRUE;
2593
2594 while (*s != 0)
2595 {
2596 uschar *ss = parse_find_address_end(s, FALSE);
2597 uschar *recipient,*errmess;
2598 int terminator = *ss;
2599 int start, end, domain;
2600
2601 /* Temporarily terminate the string at this point, and extract the
2602 operative address within, allowing group syntax. */
2603
2604 *ss = 0;
2605 recipient = parse_extract_address(s,&errmess,&start,&end,&domain,FALSE);
2606 *ss = terminator;
2607
2608 /* If we found a valid recipient that has a domain, compare it with the
2609 envelope recipient. Local parts are compared case-sensitively, domains
2610 case-insensitively. By comparing from the start with length "domain", we
2611 include the "@" at the end, which ensures that we are comparing the whole
2612 local part of each address. */
2613
2614 if (recipient != NULL && domain != 0)
2615 {
2616 found = Ustrncmp(recipient, address, domain) == 0 &&
2617 strcmpic(recipient + domain, address + domain) == 0;
2618 if (found) break;
2619 }
2620
2621 /* Advance to the next address */
2622
2623 s = ss + (terminator? 1:0);
2624 while (isspace(*s)) s++;
2625 } /* Next address */
2626
2627 parse_allow_group = FALSE;
2628 parse_found_group = FALSE;
2629 } /* Next header (if found is false) */
2630
2631 if (!found) return FAIL;
2632 } /* Next recipient */
2633
2634 return OK;
2635 }
2636
2637
2638
2639 /*************************************************
2640 * Find if verified sender *
2641 *************************************************/
2642
2643 /* Usually, just a single address is verified as the sender of the message.
2644 However, Exim can be made to verify other addresses as well (often related in
2645 some way), and this is useful in some environments. There may therefore be a
2646 chain of such addresses that have previously been tested. This function finds
2647 whether a given address is on the chain.
2648
2649 Arguments: the address to be verified
2650 Returns: pointer to an address item, or NULL
2651 */
2652
2653 address_item *
2654 verify_checked_sender(uschar *sender)
2655 {
2656 address_item *addr;
2657 for (addr = sender_verified_list; addr != NULL; addr = addr->next)
2658 if (Ustrcmp(sender, addr->address) == 0) break;
2659 return addr;
2660 }
2661
2662
2663
2664
2665
2666 /*************************************************
2667 * Get valid header address *
2668 *************************************************/
2669
2670 /* Scan the originator headers of the message, looking for an address that
2671 verifies successfully. RFC 822 says:
2672
2673 o The "Sender" field mailbox should be sent notices of
2674 any problems in transport or delivery of the original
2675 messages. If there is no "Sender" field, then the
2676 "From" field mailbox should be used.
2677
2678 o If the "Reply-To" field exists, then the reply should
2679 go to the addresses indicated in that field and not to
2680 the address(es) indicated in the "From" field.
2681
2682 So we check a Sender field if there is one, else a Reply_to field, else a From
2683 field. As some strange messages may have more than one of these fields,
2684 especially if they are resent- fields, check all of them if there is more than
2685 one.
2686
2687 Arguments:
2688 user_msgptr points to where to put a user error message
2689 log_msgptr points to where to put a log error message
2690 callout timeout for callout check (passed to verify_address())
2691 callout_overall overall callout timeout (ditto)
2692 callout_connect connect callout timeout (ditto)
2693 se_mailfrom mailfrom for verify; NULL => ""
2694 pm_mailfrom sender for pm callout check (passed to verify_address())
2695 options callout options (passed to verify_address())
2696 verrno where to put the address basic_errno
2697
2698 If log_msgptr is set to something without setting user_msgptr, the caller
2699 normally uses log_msgptr for both things.
2700
2701 Returns: result of the verification attempt: OK, FAIL, or DEFER;
2702 FAIL is given if no appropriate headers are found
2703 */
2704
2705 int
2706 verify_check_header_address(uschar **user_msgptr, uschar **log_msgptr,
2707 int callout, int callout_overall, int callout_connect, uschar *se_mailfrom,
2708 uschar *pm_mailfrom, int options, int *verrno)
2709 {
2710 static int header_types[] = { htype_sender, htype_reply_to, htype_from };
2711 BOOL done = FALSE;
2712 int yield = FAIL;
2713 int i;
2714
2715 for (i = 0; i < 3 && !done; i++)
2716 {
2717 header_line *h;
2718 for (h = header_list; h != NULL && !done; h = h->next)
2719 {
2720 int terminator, new_ok;
2721 uschar *s, *ss, *endname;
2722
2723 if (h->type != header_types[i]) continue;
2724 s = endname = Ustrchr(h->text, ':') + 1;
2725
2726 /* Scan the addresses in the header, enabling group syntax. Note that we
2727 have to reset this after the header has been scanned. */
2728
2729 parse_allow_group = TRUE;
2730
2731 while (*s != 0)
2732 {
2733 address_item *vaddr;
2734
2735 while (isspace(*s) || *s == ',') s++;
2736 if (*s == 0) break; /* End of header */
2737
2738 ss = parse_find_address_end(s, FALSE);
2739
2740 /* The terminator is a comma or end of header, but there may be white
2741 space preceding it (including newline for the last address). Move back
2742 past any white space so we can check against any cached envelope sender
2743 address verifications. */
2744
2745 while (isspace(ss[-1])) ss--;
2746 terminator = *ss;
2747 *ss = 0;
2748
2749 HDEBUG(D_verify) debug_printf("verifying %.*s header address %s\n",
2750 (int)(endname - h->text), h->text, s);
2751
2752 /* See if we have already verified this address as an envelope sender,
2753 and if so, use the previous answer. */
2754
2755 vaddr = verify_checked_sender(s);
2756
2757 if (vaddr != NULL && /* Previously checked */
2758 (callout <= 0 || /* No callout needed; OR */
2759 vaddr->special_action > 256)) /* Callout was done */
2760 {
2761 new_ok = vaddr->special_action & 255;
2762 HDEBUG(D_verify) debug_printf("previously checked as envelope sender\n");
2763 *ss = terminator; /* Restore shortened string */
2764 }
2765
2766 /* Otherwise we run the verification now. We must restore the shortened
2767 string before running the verification, so the headers are correct, in
2768 case there is any rewriting. */
2769
2770 else
2771 {
2772 int start, end, domain;
2773 uschar *address = parse_extract_address(s, log_msgptr, &start, &end,
2774 &domain, FALSE);
2775
2776 *ss = terminator;
2777
2778 /* If we found an empty address, just carry on with the next one, but
2779 kill the message. */
2780
2781 if (address == NULL && Ustrcmp(*log_msgptr, "empty address") == 0)
2782 {
2783 *log_msgptr = NULL;
2784 s = ss;
2785 continue;
2786 }
2787
2788 /* If verification failed because of a syntax error, fail this
2789 function, and ensure that the failing address gets added to the error
2790 message. */
2791
2792 if (address == NULL)
2793 {
2794 new_ok = FAIL;
2795 while (ss > s && isspace(ss[-1])) ss--;
2796 *log_msgptr = string_sprintf("syntax error in '%.*s' header when "
2797 "scanning for sender: %s in \"%.*s\"",
2798 endname - h->text, h->text, *log_msgptr, ss - s, s);
2799 yield = FAIL;
2800 done = TRUE;
2801 break;
2802 }
2803
2804 /* Else go ahead with the sender verification. But it isn't *the*
2805 sender of the message, so set vopt_fake_sender to stop sender_address
2806 being replaced after rewriting or qualification. */
2807
2808 else
2809 {
2810 vaddr = deliver_make_addr(address, FALSE);
2811 new_ok = verify_address(vaddr, NULL, options | vopt_fake_sender,
2812 callout, callout_overall, callout_connect, se_mailfrom,
2813 pm_mailfrom, NULL);
2814 }
2815 }
2816
2817 /* We now have the result, either newly found, or cached. If we are
2818 giving out error details, set a specific user error. This means that the
2819 last of these will be returned to the user if all three fail. We do not
2820 set a log message - the generic one below will be used. */
2821
2822 if (new_ok != OK)
2823 {
2824 *verrno = vaddr->basic_errno;
2825 if (smtp_return_error_details)
2826 {
2827 *user_msgptr = string_sprintf("Rejected after DATA: "
2828 "could not verify \"%.*s\" header address\n%s: %s",
2829 endname - h->text, h->text, vaddr->address, vaddr->message);
2830 }
2831 }
2832
2833 /* Success or defer */
2834
2835 if (new_ok == OK)
2836 {
2837 yield = OK;
2838 done = TRUE;
2839 break;
2840 }
2841
2842 if (new_ok == DEFER) yield = DEFER;
2843
2844 /* Move on to any more addresses in the header */
2845
2846 s = ss;
2847 } /* Next address */
2848
2849 parse_allow_group = FALSE;
2850 parse_found_group = FALSE;
2851 } /* Next header, unless done */
2852 } /* Next header type unless done */
2853
2854 if (yield == FAIL && *log_msgptr == NULL)
2855 *log_msgptr = US"there is no valid sender in any header line";
2856
2857 if (yield == DEFER && *log_msgptr == NULL)
2858 *log_msgptr = US"all attempts to verify a sender in a header line deferred";
2859
2860 return yield;
2861 }
2862
2863
2864
2865
2866 /*************************************************
2867 * Get RFC 1413 identification *
2868 *************************************************/
2869
2870 /* Attempt to get an id from the sending machine via the RFC 1413 protocol. If
2871 the timeout is set to zero, then the query is not done. There may also be lists
2872 of hosts and nets which are exempt. To guard against malefactors sending
2873 non-printing characters which could, for example, disrupt a message's headers,
2874 make sure the string consists of printing characters only.
2875
2876 Argument:
2877 port the port to connect to; usually this is IDENT_PORT (113), but when
2878 running in the test harness with -bh a different value is used.
2879
2880 Returns: nothing
2881
2882 Side effect: any received ident value is put in sender_ident (NULL otherwise)
2883 */
2884
2885 void
2886 verify_get_ident(int port)
2887 {
2888 int sock, host_af, qlen;
2889 int received_sender_port, received_interface_port, n;
2890 uschar *p;
2891 uschar buffer[2048];
2892
2893 /* Default is no ident. Check whether we want to do an ident check for this
2894 host. */
2895
2896 sender_ident = NULL;
2897 if (rfc1413_query_timeout <= 0 || verify_check_host(&rfc1413_hosts) != OK)
2898 return;
2899
2900 DEBUG(D_ident) debug_printf("doing ident callback\n");
2901
2902 /* Set up a connection to the ident port of the remote host. Bind the local end
2903 to the incoming interface address. If the sender host address is an IPv6
2904 address, the incoming interface address will also be IPv6. */
2905
2906 host_af = (Ustrchr(sender_host_address, ':') == NULL)? AF_INET : AF_INET6;
2907 sock = ip_socket(SOCK_STREAM, host_af);
2908 if (sock < 0) return;
2909
2910 if (ip_bind(sock, host_af, interface_address, 0) < 0)
2911 {
2912 DEBUG(D_ident) debug_printf("bind socket for ident failed: %s\n",
2913 strerror(errno));
2914 goto END_OFF;
2915 }
2916
2917 if (ip_connect(sock, host_af, sender_host_address, port, rfc1413_query_timeout)
2918 < 0)
2919 {
2920 if (errno == ETIMEDOUT && LOGGING(ident_timeout))
2921 {
2922 log_write(0, LOG_MAIN, "ident connection to %s timed out",
2923 sender_host_address);
2924 }
2925 else
2926 {
2927 DEBUG(D_ident) debug_printf("ident connection to %s failed: %s\n",
2928 sender_host_address, strerror(errno));
2929 }
2930 goto END_OFF;
2931 }
2932
2933 /* Construct and send the query. */
2934
2935 sprintf(CS buffer, "%d , %d\r\n", sender_host_port, interface_port);
2936 qlen = Ustrlen(buffer);
2937 if (send(sock, buffer, qlen, 0) < 0)
2938 {
2939 DEBUG(D_ident) debug_printf("ident send failed: %s\n", strerror(errno));
2940 goto END_OFF;
2941 }
2942
2943 /* Read a response line. We put it into the rest of the buffer, using several
2944 recv() calls if necessary. */
2945
2946 p = buffer + qlen;
2947
2948 for (;;)
2949 {
2950 uschar *pp;
2951 int count;
2952 int size = sizeof(buffer) - (p - buffer);
2953
2954 if (size <= 0) goto END_OFF; /* Buffer filled without seeing \n. */
2955 count = ip_recv(sock, p, size, rfc1413_query_timeout);
2956 if (count <= 0) goto END_OFF; /* Read error or EOF */
2957
2958 /* Scan what we just read, to see if we have reached the terminating \r\n. Be
2959 generous, and accept a plain \n terminator as well. The only illegal
2960 character is 0. */
2961
2962 for (pp = p; pp < p + count; pp++)
2963 {
2964 if (*pp == 0) goto END_OFF; /* Zero octet not allowed */
2965 if (*pp == '\n')
2966 {
2967 if (pp[-1] == '\r') pp--;
2968 *pp = 0;
2969 goto GOT_DATA; /* Break out of both loops */
2970 }
2971 }
2972
2973 /* Reached the end of the data without finding \n. Let the loop continue to
2974 read some more, if there is room. */
2975
2976 p = pp;
2977 }
2978
2979 GOT_DATA:
2980
2981 /* We have received a line of data. Check it carefully. It must start with the
2982 same two port numbers that we sent, followed by data as defined by the RFC. For
2983 example,
2984
2985 12345 , 25 : USERID : UNIX :root
2986
2987 However, the amount of white space may be different to what we sent. In the
2988 "osname" field there may be several sub-fields, comma separated. The data we
2989 actually want to save follows the third colon. Some systems put leading spaces
2990 in it - we discard those. */
2991
2992 if (sscanf(CS buffer + qlen, "%d , %d%n", &received_sender_port,
2993 &received_interface_port, &n) != 2 ||
2994 received_sender_port != sender_host_port ||
2995 received_interface_port != interface_port)
2996 goto END_OFF;
2997
2998 p = buffer + qlen + n;
2999 while(isspace(*p)) p++;
3000 if (*p++ != ':') goto END_OFF;
3001 while(isspace(*p)) p++;
3002 if (Ustrncmp(p, "USERID", 6) != 0) goto END_OFF;
3003 p += 6;
3004 while(isspace(*p)) p++;
3005 if (*p++ != ':') goto END_OFF;
3006 while (*p != 0 && *p != ':') p++;
3007 if (*p++ == 0) goto END_OFF;
3008 while(isspace(*p)) p++;
3009 if (*p == 0) goto END_OFF;
3010
3011 /* The rest of the line is the data we want. We turn it into printing
3012 characters when we save it, so that it cannot mess up the format of any logging
3013 or Received: lines into which it gets inserted. We keep a maximum of 127
3014 characters. The deconst cast is ok as we fed a nonconst to string_printing() */
3015
3016 sender_ident = US string_printing(string_copyn(p, 127));
3017 DEBUG(D_ident) debug_printf("sender_ident = %s\n", sender_ident);
3018
3019 END_OFF:
3020 (void)close(sock);
3021 return;
3022 }
3023
3024
3025
3026
3027 /*************************************************
3028 * Match host to a single host-list item *
3029 *************************************************/
3030
3031 /* This function compares a host (name or address) against a single item
3032 from a host list. The host name gets looked up if it is needed and is not
3033 already known. The function is called from verify_check_this_host() via
3034 match_check_list(), which is why most of its arguments are in a single block.
3035
3036 Arguments:
3037 arg the argument block (see below)
3038 ss the host-list item
3039 valueptr where to pass back looked up data, or NULL
3040 error for error message when returning ERROR
3041
3042 The block contains:
3043 host_name (a) the host name, or
3044 (b) NULL, implying use sender_host_name and
3045 sender_host_aliases, looking them up if required, or
3046 (c) the empty string, meaning that only IP address matches
3047 are permitted
3048 host_address the host address
3049 host_ipv4 the IPv4 address taken from an IPv6 one
3050
3051 Returns: OK matched
3052 FAIL did not match
3053 DEFER lookup deferred
3054 ERROR (a) failed to find the host name or IP address, or
3055 (b) unknown lookup type specified, or
3056 (c) host name encountered when only IP addresses are
3057 being matched
3058 */
3059
3060 int
3061 check_host(void *arg, const uschar *ss, const uschar **valueptr, uschar **error)
3062 {
3063 check_host_block *cb = (check_host_block *)arg;
3064 int mlen = -1;
3065 int maskoffset;
3066 BOOL iplookup = FALSE;
3067 BOOL isquery = FALSE;
3068 BOOL isiponly = cb->host_name != NULL && cb->host_name[0] == 0;
3069 const uschar *t;
3070 uschar *semicolon;
3071 uschar **aliases;
3072
3073 /* Optimize for the special case when the pattern is "*". */
3074
3075 if (*ss == '*' && ss[1] == 0) return OK;
3076
3077 /* If the pattern is empty, it matches only in the case when there is no host -
3078 this can occur in ACL checking for SMTP input using the -bs option. In this
3079 situation, the host address is the empty string. */
3080
3081 if (cb->host_address[0] == 0) return (*ss == 0)? OK : FAIL;
3082 if (*ss == 0) return FAIL;
3083
3084 /* If the pattern is precisely "@" then match against the primary host name,
3085 provided that host name matching is permitted; if it's "@[]" match against the
3086 local host's IP addresses. */
3087
3088 if (*ss == '@')
3089 {
3090 if (ss[1] == 0)
3091 {
3092 if (isiponly) return ERROR;
3093 ss = primary_hostname;
3094 }
3095 else if (Ustrcmp(ss, "@[]") == 0)
3096 {
3097 ip_address_item *ip;
3098 for (ip = host_find_interfaces(); ip != NULL; ip = ip->next)
3099 if (Ustrcmp(ip->address, cb->host_address) == 0) return OK;
3100 return FAIL;
3101 }
3102 }
3103
3104 /* If the pattern is an IP address, optionally followed by a bitmask count, do
3105 a (possibly masked) comparision with the current IP address. */
3106
3107 if (string_is_ip_address(ss, &maskoffset) != 0)
3108 return (host_is_in_net(cb->host_address, ss, maskoffset)? OK : FAIL);
3109
3110 /* The pattern is not an IP address. A common error that people make is to omit
3111 one component of an IPv4 address, either by accident, or believing that, for
3112 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,
3113 which it isn't. (Those applications that do accept 1.2.3 as an IP address
3114 interpret it as 1.2.0.3 because the final component becomes 16-bit - this is an
3115 ancient specification.) To aid in debugging these cases, we give a specific
3116 error if the pattern contains only digits and dots or contains a slash preceded
3117 only by digits and dots (a slash at the start indicates a file name and of
3118 course slashes may be present in lookups, but not preceded only by digits and
3119 dots). */
3120
3121 for (t = ss; isdigit(*t) || *t == '.'; t++);
3122 if (*t == 0 || (*t == '/' && t != ss))
3123 {
3124 *error = US"malformed IPv4 address or address mask";
3125 return ERROR;
3126 }
3127
3128 /* See if there is a semicolon in the pattern */
3129
3130 semicolon = Ustrchr(ss, ';');
3131
3132 /* If we are doing an IP address only match, then all lookups must be IP
3133 address lookups, even if there is no "net-". */
3134
3135 if (isiponly)
3136 {
3137 iplookup = semicolon != NULL;
3138 }
3139
3140 /* Otherwise, if the item is of the form net[n]-lookup;<file|query> then it is
3141 a lookup on a masked IP network, in textual form. We obey this code even if we
3142 have already set iplookup, so as to skip over the "net-" prefix and to set the
3143 mask length. The net- stuff really only applies to single-key lookups where the
3144 key is implicit. For query-style lookups the key is specified in the query.
3145 From release 4.30, the use of net- for query style is no longer needed, but we
3146 retain it for backward compatibility. */
3147
3148 if (Ustrncmp(ss, "net", 3) == 0 && semicolon != NULL)
3149 {
3150 mlen = 0;
3151 for (t = ss + 3; isdigit(*t); t++) mlen = mlen * 10 + *t - '0';
3152 if (mlen == 0 && t == ss+3) mlen = -1; /* No mask supplied */
3153 iplookup = (*t++ == '-');
3154 }
3155 else t = ss;
3156
3157 /* Do the IP address lookup if that is indeed what we have */
3158
3159 if (iplookup)
3160 {
3161 int insize;
3162 int search_type;
3163 int incoming[4];
3164 void *handle;
3165 uschar *filename, *key, *result;
3166 uschar buffer[64];
3167
3168 /* Find the search type */
3169
3170 search_type = search_findtype(t, semicolon - t);
3171
3172 if (search_type < 0) log_write(0, LOG_MAIN|LOG_PANIC_DIE, "%s",
3173 search_error_message);
3174
3175 /* Adjust parameters for the type of lookup. For a query-style lookup, there
3176 is no file name, and the "key" is just the query. For query-style with a file
3177 name, we have to fish the file off the start of the query. For a single-key
3178 lookup, the key is the current IP address, masked appropriately, and
3179 reconverted to text form, with the mask appended. For IPv6 addresses, specify
3180 dot separators instead of colons, except when the lookup type is "iplsearch".
3181 */
3182
3183 if (mac_islookup(search_type, lookup_absfilequery))
3184 {
3185 filename = semicolon + 1;
3186 key = filename;
3187 while (*key != 0 && !isspace(*key)) key++;
3188 filename = string_copyn(filename, key - filename);
3189 while (isspace(*key)) key++;
3190 }
3191 else if (mac_islookup(search_type, lookup_querystyle))
3192 {
3193 filename = NULL;
3194 key = semicolon + 1;
3195 }
3196 else /* Single-key style */
3197 {
3198 int sep = (Ustrcmp(lookup_list[search_type]->name, "iplsearch") == 0)?
3199 ':' : '.';
3200 insize = host_aton(cb->host_address, incoming);
3201 host_mask(insize, incoming, mlen);
3202 (void)host_nmtoa(insize, incoming, mlen, buffer, sep);
3203 key = buffer;
3204 filename = semicolon + 1;
3205 }
3206
3207 /* Now do the actual lookup; note that there is no search_close() because
3208 of the caching arrangements. */
3209
3210 handle = search_open(filename, search_type, 0, NULL, NULL);
3211 if (handle == NULL) log_write(0, LOG_MAIN|LOG_PANIC_DIE, "%s",
3212 search_error_message);
3213 result = search_find(handle, filename, key, -1, NULL, 0, 0, NULL);
3214 if (valueptr != NULL) *valueptr = result;
3215 return (result != NULL)? OK : search_find_defer? DEFER: FAIL;
3216 }
3217
3218 /* The pattern is not an IP address or network reference of any kind. That is,
3219 it is a host name pattern. If this is an IP only match, there's an error in the
3220 host list. */
3221
3222 if (isiponly)
3223 {
3224 *error = US"cannot match host name in match_ip list";
3225 return ERROR;
3226 }
3227
3228 /* Check the characters of the pattern to see if they comprise only letters,
3229 digits, full stops, and hyphens (the constituents of domain names). Allow
3230 underscores, as they are all too commonly found. Sigh. Also, if
3231 allow_utf8_domains is set, allow top-bit characters. */
3232
3233 for (t = ss; *t != 0; t++)
3234 if (!isalnum(*t) && *t != '.' && *t != '-' && *t != '_' &&
3235 (!allow_utf8_domains || *t < 128)) break;
3236
3237 /* If the pattern is a complete domain name, with no fancy characters, look up
3238 its IP address and match against that. Note that a multi-homed host will add
3239 items to the chain. */
3240
3241 if (*t == 0)
3242 {
3243 int rc;
3244 host_item h;
3245 h.next = NULL;
3246 h.name = ss;
3247 h.address = NULL;
3248 h.mx = MX_NONE;
3249
3250 /* Using byname rather than bydns here means we cannot determine dnssec
3251 status. On the other hand it is unclear how that could be either
3252 propagated up or enforced. */
3253
3254 rc = host_find_byname(&h, NULL, HOST_FIND_QUALIFY_SINGLE, NULL, FALSE);
3255 if (rc == HOST_FOUND || rc == HOST_FOUND_LOCAL)
3256 {
3257 host_item *hh;
3258 for (hh = &h; hh != NULL; hh = hh->next)
3259 {
3260 if (host_is_in_net(hh->address, cb->host_address, 0)) return OK;
3261 }
3262 return FAIL;
3263 }
3264 if (rc == HOST_FIND_AGAIN) return DEFER;
3265 *error = string_sprintf("failed to find IP address for %s", ss);
3266 return ERROR;
3267 }
3268
3269 /* Almost all subsequent comparisons require the host name, and can be done
3270 using the general string matching function. When this function is called for
3271 outgoing hosts, the name is always given explicitly. If it is NULL, it means we
3272 must use sender_host_name and its aliases, looking them up if necessary. */
3273
3274 if (cb->host_name != NULL) /* Explicit host name given */
3275 return match_check_string(cb->host_name, ss, -1, TRUE, TRUE, TRUE,
3276 valueptr);
3277
3278 /* Host name not given; in principle we need the sender host name and its
3279 aliases. However, for query-style lookups, we do not need the name if the
3280 query does not contain $sender_host_name. From release 4.23, a reference to
3281 $sender_host_name causes it to be looked up, so we don't need to do the lookup
3282 on spec. */
3283
3284 if ((semicolon = Ustrchr(ss, ';')) != NULL)
3285 {
3286 const uschar *affix;
3287 int partial, affixlen, starflags, id;
3288
3289 *semicolon = 0;
3290 id = search_findtype_partial(ss, &partial, &affix, &affixlen, &starflags);
3291 *semicolon=';';
3292
3293 if (id < 0) /* Unknown lookup type */
3294 {
3295 log_write(0, LOG_MAIN|LOG_PANIC, "%s in host list item \"%s\"",
3296 search_error_message, ss);
3297 return DEFER;
3298 }
3299 isquery = mac_islookup(id, lookup_querystyle|lookup_absfilequery);
3300 }
3301
3302 if (isquery)
3303 {
3304 switch(match_check_string(US"", ss, -1, TRUE, TRUE, TRUE, valueptr))
3305 {
3306 case OK: return OK;
3307 case DEFER: return DEFER;
3308 default: return FAIL;
3309 }
3310 }
3311
3312 /* Not a query-style lookup; must ensure the host name is present, and then we
3313 do a check on the name and all its aliases. */
3314
3315 if (sender_host_name == NULL)
3316 {
3317 HDEBUG(D_host_lookup)
3318 debug_printf("sender host name required, to match against %s\n", ss);
3319 if (host_lookup_failed || host_name_lookup() != OK)
3320 {
3321 *error = string_sprintf("failed to find host name for %s",
3322 sender_host_address);;
3323 return ERROR;
3324 }
3325 host_build_sender_fullhost();
3326 }
3327
3328 /* Match on the sender host name, using the general matching function */
3329
3330 switch(match_check_string(sender_host_name, ss, -1, TRUE, TRUE, TRUE,
3331 valueptr))
3332 {
3333 case OK: return OK;
3334 case DEFER: return DEFER;
3335 }
3336
3337 /* If there are aliases, try matching on them. */
3338
3339 aliases = sender_host_aliases;
3340 while (*aliases != NULL)
3341 {
3342 switch(match_check_string(*aliases++, ss, -1, TRUE, TRUE, TRUE, valueptr))
3343 {
3344 case OK: return OK;
3345 case DEFER: return DEFER;
3346 }
3347 }
3348 return FAIL;
3349 }
3350
3351
3352
3353
3354 /*************************************************
3355 * Check a specific host matches a host list *
3356 *************************************************/
3357
3358 /* This function is passed a host list containing items in a number of
3359 different formats and the identity of a host. Its job is to determine whether
3360 the given host is in the set of hosts defined by the list. The host name is
3361 passed as a pointer so that it can be looked up if needed and not already
3362 known. This is commonly the case when called from verify_check_host() to check
3363 an incoming connection. When called from elsewhere the host name should usually
3364 be set.
3365
3366 This function is now just a front end to match_check_list(), which runs common
3367 code for scanning a list. We pass it the check_host() function to perform a
3368 single test.
3369
3370 Arguments:
3371 listptr pointer to the host list
3372 cache_bits pointer to cache for named lists, or NULL
3373 host_name the host name or NULL, implying use sender_host_name and
3374 sender_host_aliases, looking them up if required
3375 host_address the IP address
3376 valueptr if not NULL, data from a lookup is passed back here
3377
3378 Returns: OK if the host is in the defined set
3379 FAIL if the host is not in the defined set,
3380 DEFER if a data lookup deferred (not a host lookup)
3381
3382 If the host name was needed in order to make a comparison, and could not be
3383 determined from the IP address, the result is FAIL unless the item
3384 "+allow_unknown" was met earlier in the list, in which case OK is returned. */
3385
3386 int
3387 verify_check_this_host(const uschar **listptr, unsigned int *cache_bits,
3388 const uschar *host_name, const uschar *host_address, const uschar **valueptr)
3389 {
3390 int rc;
3391 unsigned int *local_cache_bits = cache_bits;
3392 const uschar *save_host_address = deliver_host_address;
3393 check_host_block cb;
3394 cb.host_name = host_name;
3395 cb.host_address = host_address;
3396
3397 if (valueptr != NULL) *valueptr = NULL;
3398
3399 /* If the host address starts off ::ffff: it is an IPv6 address in
3400 IPv4-compatible mode. Find the IPv4 part for checking against IPv4
3401 addresses. */
3402
3403 cb.host_ipv4 = (Ustrncmp(host_address, "::ffff:", 7) == 0)?
3404 host_address + 7 : host_address;
3405
3406 /* During the running of the check, put the IP address into $host_address. In
3407 the case of calls from the smtp transport, it will already be there. However,
3408 in other calls (e.g. when testing ignore_target_hosts), it won't. Just to be on
3409 the safe side, any existing setting is preserved, though as I write this
3410 (November 2004) I can't see any cases where it is actually needed. */
3411
3412 deliver_host_address = host_address;
3413 rc = match_check_list(
3414 listptr, /* the list */
3415 0, /* separator character */
3416 &hostlist_anchor, /* anchor pointer */
3417 &local_cache_bits, /* cache pointer */
3418 check_host, /* function for testing */
3419 &cb, /* argument for function */
3420 MCL_HOST, /* type of check */
3421 (host_address == sender_host_address)?
3422 US"host" : host_address, /* text for debugging */
3423 valueptr); /* where to pass back data */
3424 deliver_host_address = save_host_address;
3425 return rc;
3426 }
3427
3428
3429
3430
3431 /*************************************************
3432 * Check the given host item matches a list *
3433 *************************************************/
3434 int
3435 verify_check_given_host(uschar **listptr, host_item *host)
3436 {
3437 return verify_check_this_host(CUSS listptr, NULL, host->name, host->address, NULL);
3438 }
3439
3440 /*************************************************
3441 * Check the remote host matches a list *
3442 *************************************************/
3443
3444 /* This is a front end to verify_check_