Cutthrough: avoid use of callout result cache
[exim.git] / src / src / verify.c
1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
4
5 /* Copyright (c) University of Cambridge 1995 - 2016 */
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 int yield = OK;
159 int old_domain_cache_result = ccache_accept;
160 BOOL done = FALSE;
161 uschar *address_key;
162 uschar *from_address;
163 uschar *random_local_part = NULL;
164 const uschar *save_deliver_domain = deliver_domain;
165 uschar **failure_ptr = options & vopt_is_recipient
166 ? &recipient_verify_failure : &sender_verify_failure;
167 open_db dbblock;
168 open_db *dbm_file = NULL;
169 dbdata_callout_cache new_domain_record;
170 dbdata_callout_cache_address new_address_record;
171 host_item *host;
172 time_t callout_start_time;
173 uschar peer_offered = 0;
174
175 new_domain_record.result = ccache_unknown;
176 new_domain_record.postmaster_result = ccache_unknown;
177 new_domain_record.random_result = ccache_unknown;
178
179 memset(&new_address_record, 0, sizeof(new_address_record));
180
181 /* For a recipient callout, the key used for the address cache record must
182 include the sender address if we are using the real sender in the callout,
183 because that may influence the result of the callout. */
184
185 address_key = addr->address;
186 from_address = US"";
187
188 if (options & vopt_is_recipient)
189 {
190 if (options & vopt_callout_recipsender)
191 {
192 address_key = string_sprintf("%s/<%s>", addr->address, sender_address);
193 from_address = sender_address;
194 if (cutthrough.delivery) options |= vopt_callout_no_cache;
195 }
196 else if (options & vopt_callout_recippmaster)
197 {
198 address_key = string_sprintf("%s/<postmaster@%s>", addr->address,
199 qualify_domain_sender);
200 from_address = string_sprintf("postmaster@%s", qualify_domain_sender);
201 }
202 }
203
204 /* For a sender callout, we must adjust the key if the mailfrom address is not
205 empty. */
206
207 else
208 {
209 from_address = (se_mailfrom == NULL)? US"" : se_mailfrom;
210 if (from_address[0] != 0)
211 address_key = string_sprintf("%s/<%s>", addr->address, from_address);
212 }
213
214 /* Open the callout cache database, it it exists, for reading only at this
215 stage, unless caching has been disabled. */
216
217 if (options & vopt_callout_no_cache)
218 {
219 HDEBUG(D_verify) debug_printf("callout cache: disabled by no_cache\n");
220 }
221 else if ((dbm_file = dbfn_open(US"callout", O_RDWR, &dbblock, FALSE)) == NULL)
222 {
223 HDEBUG(D_verify) debug_printf("callout cache: not available\n");
224 }
225
226 /* If a cache database is available see if we can avoid the need to do an
227 actual callout by making use of previously-obtained data. */
228
229 if (dbm_file != NULL)
230 {
231 dbdata_callout_cache_address *cache_address_record;
232 dbdata_callout_cache *cache_record = get_callout_cache_record(dbm_file,
233 addr->domain, US"domain",
234 callout_cache_domain_positive_expire,
235 callout_cache_domain_negative_expire);
236
237 /* If an unexpired cache record was found for this domain, see if the callout
238 process can be short-circuited. */
239
240 if (cache_record != NULL)
241 {
242 /* In most cases, if an early command (up to and including MAIL FROM:<>)
243 was rejected, there is no point carrying on. The callout fails. However, if
244 we are doing a recipient verification with use_sender or use_postmaster
245 set, a previous failure of MAIL FROM:<> doesn't count, because this time we
246 will be using a non-empty sender. We have to remember this situation so as
247 not to disturb the cached domain value if this whole verification succeeds
248 (we don't want it turning into "accept"). */
249
250 old_domain_cache_result = cache_record->result;
251
252 if (cache_record->result == ccache_reject ||
253 (*from_address == 0 && cache_record->result == ccache_reject_mfnull))
254 {
255 setflag(addr, af_verify_nsfail);
256 HDEBUG(D_verify)
257 debug_printf("callout cache: domain gave initial rejection, or "
258 "does not accept HELO or MAIL FROM:<>\n");
259 setflag(addr, af_verify_nsfail);
260 addr->user_message = US"(result of an earlier callout reused).";
261 yield = FAIL;
262 *failure_ptr = US"mail";
263 goto END_CALLOUT;
264 }
265
266 /* If a previous check on a "random" local part was accepted, we assume
267 that the server does not do any checking on local parts. There is therefore
268 no point in doing the callout, because it will always be successful. If a
269 random check previously failed, arrange not to do it again, but preserve
270 the data in the new record. If a random check is required but hasn't been
271 done, skip the remaining cache processing. */
272
273 if (options & vopt_callout_random) switch(cache_record->random_result)
274 {
275 case ccache_accept:
276 HDEBUG(D_verify)
277 debug_printf("callout cache: domain accepts random addresses\n");
278 goto END_CALLOUT; /* Default yield is OK */
279
280 case ccache_reject:
281 HDEBUG(D_verify)
282 debug_printf("callout cache: domain rejects random addresses\n");
283 options &= ~vopt_callout_random;
284 new_domain_record.random_result = ccache_reject;
285 new_domain_record.random_stamp = cache_record->random_stamp;
286 break;
287
288 default:
289 HDEBUG(D_verify)
290 debug_printf("callout cache: need to check random address handling "
291 "(not cached or cache expired)\n");
292 goto END_CACHE;
293 }
294
295 /* If a postmaster check is requested, but there was a previous failure,
296 there is again no point in carrying on. If a postmaster check is required,
297 but has not been done before, we are going to have to do a callout, so skip
298 remaining cache processing. */
299
300 if (pm_mailfrom != NULL)
301 {
302 if (cache_record->postmaster_result == ccache_reject)
303 {
304 setflag(addr, af_verify_pmfail);
305 HDEBUG(D_verify)
306 debug_printf("callout cache: domain does not accept "
307 "RCPT TO:<postmaster@domain>\n");
308 yield = FAIL;
309 *failure_ptr = US"postmaster";
310 setflag(addr, af_verify_pmfail);
311 addr->user_message = US"(result of earlier verification reused).";
312 goto END_CALLOUT;
313 }
314 if (cache_record->postmaster_result == ccache_unknown)
315 {
316 HDEBUG(D_verify)
317 debug_printf("callout cache: need to check RCPT "
318 "TO:<postmaster@domain> (not cached or cache expired)\n");
319 goto END_CACHE;
320 }
321
322 /* If cache says OK, set pm_mailfrom NULL to prevent a redundant
323 postmaster check if the address itself has to be checked. Also ensure
324 that the value in the cache record is preserved (with its old timestamp).
325 */
326
327 HDEBUG(D_verify) debug_printf("callout cache: domain accepts RCPT "
328 "TO:<postmaster@domain>\n");
329 pm_mailfrom = NULL;
330 new_domain_record.postmaster_result = ccache_accept;
331 new_domain_record.postmaster_stamp = cache_record->postmaster_stamp;
332 }
333 }
334
335 /* We can't give a result based on information about the domain. See if there
336 is an unexpired cache record for this specific address (combined with the
337 sender address if we are doing a recipient callout with a non-empty sender).
338 */
339
340 cache_address_record = (dbdata_callout_cache_address *)
341 get_callout_cache_record(dbm_file,
342 address_key, US"address",
343 callout_cache_positive_expire,
344 callout_cache_negative_expire);
345
346 if (cache_address_record != NULL)
347 {
348 if (cache_address_record->result == ccache_accept)
349 {
350 HDEBUG(D_verify)
351 debug_printf("callout cache: address record is positive\n");
352 }
353 else
354 {
355 HDEBUG(D_verify)
356 debug_printf("callout cache: address record is negative\n");
357 addr->user_message = US"Previous (cached) callout verification failure";
358 *failure_ptr = US"recipient";
359 yield = FAIL;
360 }
361 goto END_CALLOUT;
362 }
363
364 /* Close the cache database while we actually do the callout for real. */
365
366 END_CACHE:
367 dbfn_close(dbm_file);
368 dbm_file = NULL;
369 }
370
371 if (!addr->transport)
372 {
373 HDEBUG(D_verify) debug_printf("cannot callout via null transport\n");
374 }
375 else if (Ustrcmp(addr->transport->driver_name, "smtp") != 0)
376 log_write(0, LOG_MAIN|LOG_PANIC|LOG_CONFIG_FOR, "callout transport '%s': %s is non-smtp",
377 addr->transport->name, addr->transport->driver_name);
378 else
379 {
380 smtp_transport_options_block *ob =
381 (smtp_transport_options_block *)addr->transport->options_block;
382
383 /* The information wasn't available in the cache, so we have to do a real
384 callout and save the result in the cache for next time, unless no_cache is set,
385 or unless we have a previously cached negative random result. If we are to test
386 with a random local part, ensure that such a local part is available. If not,
387 log the fact, but carry on without randomming. */
388
389 if (options & vopt_callout_random && callout_random_local_part != NULL)
390 if (!(random_local_part = expand_string(callout_random_local_part)))
391 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand "
392 "callout_random_local_part: %s", expand_string_message);
393
394 /* Default the connect and overall callout timeouts if not set, and record the
395 time we are starting so that we can enforce it. */
396
397 if (callout_overall < 0) callout_overall = 4 * callout;
398 if (callout_connect < 0) callout_connect = callout;
399 callout_start_time = time(NULL);
400
401 /* Before doing a real callout, if this is an SMTP connection, flush the SMTP
402 output because a callout might take some time. When PIPELINING is active and
403 there are many recipients, the total time for doing lots of callouts can add up
404 and cause the client to time out. So in this case we forgo the PIPELINING
405 optimization. */
406
407 if (smtp_out != NULL && !disable_callout_flush) mac_smtp_fflush();
408
409 /* cutthrough-multi: if a nonfirst rcpt has the same routing as the first,
410 and we are holding a cutthrough conn open, we can just append the rcpt to
411 that conn for verification purposes (and later delivery also). Simplest
412 coding means skipping this whole loop and doing the append separately.
413
414 We will need to remember it has been appended so that rcpt-acl tail code
415 can do it there for the non-rcpt-verify case. For this we keep an addresscount.
416 */
417
418 /* Can we re-use an open cutthrough connection? */
419 if ( cutthrough.fd >= 0
420 && (options & (vopt_callout_recipsender | vopt_callout_recippmaster))
421 == vopt_callout_recipsender
422 && !random_local_part
423 && !pm_mailfrom
424 )
425 {
426 if (addr->transport == cutthrough.addr.transport)
427 for (host = host_list; host; host = host->next)
428 if (Ustrcmp(host->address, cutthrough.host.address) == 0)
429 {
430 int host_af;
431 uschar *interface = NULL; /* Outgoing interface to use; NULL => any */
432 int port = 25;
433
434 deliver_host = host->name;
435 deliver_host_address = host->address;
436 deliver_host_port = host->port;
437 deliver_domain = addr->domain;
438 transport_name = addr->transport->name;
439
440 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET:AF_INET6;
441
442 if (!smtp_get_interface(tf->interface, host_af, addr, &interface,
443 US"callout") ||
444 !smtp_get_port(tf->port, addr, &port, US"callout"))
445 log_write(0, LOG_MAIN|LOG_PANIC, "<%s>: %s", addr->address,
446 addr->message);
447
448 if ( ( interface == cutthrough.interface
449 || ( interface
450 && cutthrough.interface
451 && Ustrcmp(interface, cutthrough.interface) == 0
452 ) )
453 && port == cutthrough.host.port
454 )
455 {
456 uschar * resp = NULL;
457
458 /* Match! Send the RCPT TO, append the addr, set done */
459 done =
460 smtp_write_command(&ctblock, FALSE, "RCPT TO:<%.1000s>\r\n",
461 transport_rcpt_address(addr,
462 (addr->transport == NULL)? FALSE :
463 addr->transport->rcpt_include_affixes)) >= 0 &&
464 cutthrough_response('2', &resp) == '2';
465
466 /* This would go horribly wrong if a callout fail was ignored by ACL.
467 We punt by abandoning cutthrough on a reject, like the
468 first-rcpt does. */
469
470 if (done)
471 {
472 address_item * na = store_get(sizeof(address_item));
473 *na = cutthrough.addr;
474 cutthrough.addr = *addr;
475 cutthrough.addr.host_used = &cutthrough.host;
476 cutthrough.addr.next = na;
477
478 cutthrough.nrcpt++;
479 }
480 else
481 {
482 cancel_cutthrough_connection("recipient rejected");
483 if (!resp || errno == ETIMEDOUT)
484 {
485 HDEBUG(D_verify) debug_printf("SMTP timeout\n");
486 }
487 else if (errno == 0)
488 {
489 if (*resp == 0)
490 Ustrcpy(resp, US"connection dropped");
491
492 addr->message =
493 string_sprintf("response to \"%s\" from %s [%s] was: %s",
494 big_buffer, host->name, host->address,
495 string_printing(resp));
496
497 addr->user_message =
498 string_sprintf("Callout verification failed:\n%s", resp);
499
500 /* Hard rejection ends the process */
501
502 if (resp[0] == '5') /* Address rejected */
503 {
504 yield = FAIL;
505 done = TRUE;
506 }
507 }
508 }
509 }
510 break;
511 }
512 if (!done)
513 cancel_cutthrough_connection("incompatible connection");
514 }
515
516 /* Now make connections to the hosts and do real callouts. The list of hosts
517 is passed in as an argument. */
518
519 for (host = host_list; host != NULL && !done; host = host->next)
520 {
521 smtp_inblock inblock;
522 smtp_outblock outblock;
523 int host_af;
524 int port = 25;
525 BOOL send_quit = TRUE;
526 uschar *active_hostname = smtp_active_hostname;
527 BOOL lmtp;
528 BOOL smtps;
529 BOOL esmtp;
530 BOOL suppress_tls = FALSE;
531 uschar *interface = NULL; /* Outgoing interface to use; NULL => any */
532 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
533 BOOL dane = FALSE;
534 BOOL dane_required;
535 dns_answer tlsa_dnsa;
536 #endif
537 uschar inbuffer[4096];
538 uschar outbuffer[1024];
539 uschar responsebuffer[4096];
540 uschar * size_str;
541
542 clearflag(addr, af_verify_pmfail); /* postmaster callout flag */
543 clearflag(addr, af_verify_nsfail); /* null sender callout flag */
544
545 /* Skip this host if we don't have an IP address for it. */
546
547 if (host->address == NULL)
548 {
549 DEBUG(D_verify) debug_printf("no IP address for host name %s: skipping\n",
550 host->name);
551 continue;
552 }
553
554 /* Check the overall callout timeout */
555
556 if (time(NULL) - callout_start_time >= callout_overall)
557 {
558 HDEBUG(D_verify) debug_printf("overall timeout for callout exceeded\n");
559 break;
560 }
561
562 /* Set IPv4 or IPv6 */
563
564 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET:AF_INET6;
565
566 /* Expand and interpret the interface and port strings. The latter will not
567 be used if there is a host-specific port (e.g. from a manualroute router).
568 This has to be delayed till now, because they may expand differently for
569 different hosts. If there's a failure, log it, but carry on with the
570 defaults. */
571
572 deliver_host = host->name;
573 deliver_host_address = host->address;
574 deliver_host_port = host->port;
575 deliver_domain = addr->domain;
576 transport_name = addr->transport->name;
577
578 if ( !smtp_get_interface(tf->interface, host_af, addr, &interface,
579 US"callout")
580 || !smtp_get_port(tf->port, addr, &port, US"callout")
581 )
582 log_write(0, LOG_MAIN|LOG_PANIC, "<%s>: %s", addr->address,
583 addr->message);
584
585 /* Set HELO string according to the protocol */
586 lmtp= Ustrcmp(tf->protocol, "lmtp") == 0;
587 smtps= Ustrcmp(tf->protocol, "smtps") == 0;
588
589
590 HDEBUG(D_verify) debug_printf("interface=%s port=%d\n", interface, port);
591
592 /* Set up the buffer for reading SMTP response packets. */
593
594 inblock.buffer = inbuffer;
595 inblock.buffersize = sizeof(inbuffer);
596 inblock.ptr = inbuffer;
597 inblock.ptrend = inbuffer;
598
599 /* Set up the buffer for holding SMTP commands while pipelining */
600
601 outblock.buffer = outbuffer;
602 outblock.buffersize = sizeof(outbuffer);
603 outblock.ptr = outbuffer;
604 outblock.cmd_count = 0;
605 outblock.authenticating = FALSE;
606
607 /* Connect to the host; on failure, just loop for the next one, but we
608 set the error for the last one. Use the callout_connect timeout. */
609
610 tls_retry_connection:
611
612 /* Reset the parameters of a TLS session */
613 tls_out.cipher = tls_out.peerdn = tls_out.peercert = NULL;
614
615 inblock.sock = outblock.sock =
616 smtp_connect(host, host_af, port, interface, callout_connect,
617 addr->transport);
618 if (inblock.sock < 0)
619 {
620 addr->message = string_sprintf("could not connect to %s [%s]: %s",
621 host->name, host->address, strerror(errno));
622 transport_name = NULL;
623 deliver_host = deliver_host_address = NULL;
624 deliver_domain = save_deliver_domain;
625 continue;
626 }
627
628 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
629 {
630 int rc;
631
632 tls_out.dane_verified = FALSE;
633 tls_out.tlsa_usage = 0;
634
635 dane_required =
636 verify_check_given_host(&ob->hosts_require_dane, host) == OK;
637
638 if (host->dnssec == DS_YES)
639 {
640 if( dane_required
641 || verify_check_given_host(&ob->hosts_try_dane, host) == OK
642 )
643 {
644 if ((rc = tlsa_lookup(host, &tlsa_dnsa, dane_required)) != OK)
645 return rc;
646 dane = TRUE;
647 }
648 }
649 else if (dane_required)
650 {
651 log_write(0, LOG_MAIN, "DANE error: %s lookup not DNSSEC", host->name);
652 return FAIL;
653 }
654
655 if (dane)
656 ob->tls_tempfail_tryclear = FALSE;
657 }
658 #endif /*DANE*/
659
660 /* Expand the helo_data string to find the host name to use. */
661
662 if (tf->helo_data != NULL)
663 {
664 uschar *s = expand_string(tf->helo_data);
665 if (s == NULL)
666 log_write(0, LOG_MAIN|LOG_PANIC, "<%s>: failed to expand transport's "
667 "helo_data value for callout: %s", addr->address,
668 expand_string_message);
669 else active_hostname = s;
670 }
671
672 /* Wait for initial response, and send HELO. The smtp_write_command()
673 function leaves its command in big_buffer. This is used in error responses.
674 Initialize it in case the connection is rejected. */
675
676 Ustrcpy(big_buffer, "initial connection");
677
678 /* Unless ssl-on-connect, wait for the initial greeting */
679 smtps_redo_greeting:
680
681 #ifdef SUPPORT_TLS
682 if (!smtps || (smtps && tls_out.active >= 0))
683 #endif
684 {
685 if (!(done= smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer), '2', callout)))
686 goto RESPONSE_FAILED;
687
688 #ifndef DISABLE_EVENT
689 lookup_dnssec_authenticated = host->dnssec==DS_YES ? US"yes"
690 : host->dnssec==DS_NO ? US"no" : NULL;
691 if (event_raise(addr->transport->event_action,
692 US"smtp:connect", responsebuffer))
693 {
694 lookup_dnssec_authenticated = NULL;
695 /* Logging? Debug? */
696 goto RESPONSE_FAILED;
697 }
698 lookup_dnssec_authenticated = NULL;
699 #endif
700 }
701
702 /* Not worth checking greeting line for ESMTP support */
703 if (!(esmtp = verify_check_given_host(&ob->hosts_avoid_esmtp, host) != OK))
704 DEBUG(D_transport)
705 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
706
707 tls_redo_helo:
708
709 #ifdef SUPPORT_TLS
710 if (smtps && tls_out.active < 0) /* ssl-on-connect, first pass */
711 {
712 peer_offered &= ~PEER_OFFERED_TLS;
713 ob->tls_tempfail_tryclear = FALSE;
714 }
715 else /* all other cases */
716 #endif
717
718 { esmtp_retry:
719
720 if (!(done= smtp_write_command(&outblock, FALSE, "%s %s\r\n",
721 !esmtp? "HELO" : lmtp? "LHLO" : "EHLO", active_hostname) >= 0))
722 goto SEND_FAILED;
723 if (!smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer), '2', callout))
724 {
725 if (errno != 0 || responsebuffer[0] == 0 || lmtp || !esmtp || tls_out.active >= 0)
726 {
727 done= FALSE;
728 goto RESPONSE_FAILED;
729 }
730 #ifdef SUPPORT_TLS
731 peer_offered &= ~PEER_OFFERED_TLS;
732 #endif
733 esmtp = FALSE;
734 goto esmtp_retry; /* fallback to HELO */
735 }
736
737 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
738
739 peer_offered = esmtp
740 ? ehlo_response(responsebuffer, sizeof(responsebuffer),
741 (!suppress_tls && tls_out.active < 0 ? PEER_OFFERED_TLS : 0)
742 | 0 /* no IGNQ */
743 | 0 /* no PRDR */
744 #ifdef SUPPORT_I18N
745 | (addr->prop.utf8_msg && !addr->prop.utf8_downcvt
746 ? PEER_OFFERED_UTF8 : 0)
747 #endif
748 | 0 /* no DSN */
749 | 0 /* no PIPE */
750
751 /* only care about SIZE if we have size from inbound */
752 | (message_size > 0 && ob->size_addition >= 0
753 ? PEER_OFFERED_SIZE : 0)
754 )
755 : 0;
756 }
757
758 size_str = peer_offered & PEER_OFFERED_SIZE
759 ? string_sprintf(" SIZE=%d", message_size + ob->size_addition) : US"";
760
761 #ifdef SUPPORT_TLS
762 tls_offered = !!(peer_offered & PEER_OFFERED_TLS);
763 #endif
764
765 /* If TLS is available on this connection attempt to
766 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
767 send another EHLO - the server may give a different answer in secure mode. We
768 use a separate buffer for reading the response to STARTTLS so that if it is
769 negative, the original EHLO data is available for subsequent analysis, should
770 the client not be required to use TLS. If the response is bad, copy the buffer
771 for error analysis. */
772
773 #ifdef SUPPORT_TLS
774 if ( peer_offered & PEER_OFFERED_TLS
775 && verify_check_given_host(&ob->hosts_avoid_tls, host) != OK
776 && verify_check_given_host(&ob->hosts_verify_avoid_tls, host) != OK
777 )
778 {
779 uschar buffer2[4096];
780 if ( !smtps
781 && !(done= smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") >= 0))
782 goto SEND_FAILED;
783
784 /* If there is an I/O error, transmission of this message is deferred. If
785 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
786 false, we also defer. However, if there is a temporary rejection of STARTTLS
787 and tls_tempfail_tryclear is true, or if there is an outright rejection of
788 STARTTLS, we carry on. This means we will try to send the message in clear,
789 unless the host is in hosts_require_tls (tested below). */
790
791 if (!smtps && !smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
792 ob->command_timeout))
793 {
794 if ( errno != 0
795 || buffer2[0] == 0
796 || buffer2[0] == '4' && !ob->tls_tempfail_tryclear
797 )
798 {
799 Ustrncpy(responsebuffer, buffer2, sizeof(responsebuffer));
800 done= FALSE;
801 goto RESPONSE_FAILED;
802 }
803 }
804
805 /* STARTTLS accepted or ssl-on-connect: try to negotiate a TLS session. */
806 else
807 {
808 int oldtimeout = ob->command_timeout;
809 int rc;
810
811 tls_negotiate:
812 ob->command_timeout = callout;
813 rc = tls_client_start(inblock.sock, host, addr, addr->transport
814 # ifdef EXPERIMENTAL_DANE
815 , dane ? &tlsa_dnsa : NULL
816 # endif
817 );
818 ob->command_timeout = oldtimeout;
819
820 /* TLS negotiation failed; give an error. Try in clear on a new
821 connection, if the options permit it for this host. */
822 if (rc != OK)
823 {
824 if (rc == DEFER)
825 {
826 (void)close(inblock.sock);
827 # ifndef DISABLE_EVENT
828 (void) event_raise(addr->transport->event_action,
829 US"tcp:close", NULL);
830 # endif
831 if ( ob->tls_tempfail_tryclear
832 && !smtps
833 && verify_check_given_host(&ob->hosts_require_tls, host) != OK
834 )
835 {
836 log_write(0, LOG_MAIN, "TLS session failure:"
837 " delivering unencrypted to %s [%s] (not in hosts_require_tls)",
838 host->name, host->address);
839 suppress_tls = TRUE;
840 goto tls_retry_connection;
841 }
842 }
843
844 /*save_errno = ERRNO_TLSFAILURE;*/
845 /*message = US"failure while setting up TLS session";*/
846 send_quit = FALSE;
847 done= FALSE;
848 goto TLS_FAILED;
849 }
850
851 /* TLS session is set up. Copy info for logging. */
852 addr->cipher = tls_out.cipher;
853 addr->peerdn = tls_out.peerdn;
854
855 /* For SMTPS we need to wait for the initial OK response, then do HELO. */
856 if (smtps)
857 goto smtps_redo_greeting;
858
859 /* For STARTTLS we need to redo EHLO */
860 goto tls_redo_helo;
861 }
862 }
863
864 /* If the host is required to use a secure channel, ensure that we have one. */
865 if (tls_out.active < 0)
866 if (
867 # ifdef EXPERIMENTAL_DANE
868 dane ||
869 # endif
870 verify_check_given_host(&ob->hosts_require_tls, host) == OK
871 )
872 {
873 /*save_errno = ERRNO_TLSREQUIRED;*/
874 log_write(0, LOG_MAIN,
875 "H=%s [%s]: a TLS session is required for this host, but %s",
876 host->name, host->address,
877 peer_offered & PEER_OFFERED_TLS
878 ? "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 /* For now, transport_filter by cutthrough-delivery is not supported */
889 /* Need proper integration with the proper transport mechanism. */
890 if (cutthrough.delivery)
891 {
892 if (addr->transport->filter_command)
893 {
894 cutthrough.delivery = FALSE;
895 HDEBUG(D_acl|D_v) debug_printf("Cutthrough cancelled by presence of transport filter\n");
896 }
897 #ifndef DISABLE_DKIM
898 if (ob->dkim_domain)
899 {
900 cutthrough.delivery = FALSE;
901 HDEBUG(D_acl|D_v) debug_printf("Cutthrough cancelled by presence of DKIM signing\n");
902 }
903 #endif
904 }
905
906 SEND_FAILED:
907 RESPONSE_FAILED:
908 TLS_FAILED:
909 ;
910 /* Clear down of the TLS, SMTP and TCP layers on error is handled below. */
911
912 /* Failure to accept HELO is cached; this blocks the whole domain for all
913 senders. I/O errors and defer responses are not cached. */
914
915 if (!done)
916 {
917 *failure_ptr = US"mail"; /* At or before MAIL */
918 if (errno == 0 && responsebuffer[0] == '5')
919 {
920 setflag(addr, af_verify_nsfail);
921 new_domain_record.result = ccache_reject;
922 }
923 }
924
925 #ifdef SUPPORT_I18N
926 else if ( addr->prop.utf8_msg
927 && !addr->prop.utf8_downcvt
928 && !(peer_offered & PEER_OFFERED_UTF8)
929 )
930 {
931 HDEBUG(D_acl|D_v) debug_printf("utf8 required but not offered\n");
932 errno = ERRNO_UTF8_FWD;
933 setflag(addr, af_verify_nsfail);
934 done = FALSE;
935 }
936 else if ( addr->prop.utf8_msg
937 && (addr->prop.utf8_downcvt || !(peer_offered & PEER_OFFERED_UTF8))
938 && (setflag(addr, af_utf8_downcvt),
939 from_address = string_address_utf8_to_alabel(from_address,
940 &addr->message),
941 addr->message
942 ) )
943 {
944 errno = ERRNO_EXPANDFAIL;
945 setflag(addr, af_verify_nsfail);
946 done = FALSE;
947 }
948 #endif
949
950 /* If we haven't authenticated, but are required to, give up. */
951 /* Try to AUTH */
952
953 else done = smtp_auth(responsebuffer, sizeof(responsebuffer),
954 addr, host, ob, esmtp, &inblock, &outblock) == OK &&
955
956 /* Copy AUTH info for logging */
957 ( (addr->authenticator = client_authenticator),
958 (addr->auth_id = client_authenticated_id),
959
960 /* Build a mail-AUTH string (re-using responsebuffer for convenience */
961 !smtp_mail_auth_str(responsebuffer, sizeof(responsebuffer), addr, ob)
962 ) &&
963
964 ( (addr->auth_sndr = client_authenticated_sender),
965
966 /* Send the MAIL command */
967 (smtp_write_command(&outblock, FALSE,
968 #ifdef SUPPORT_I18N
969 addr->prop.utf8_msg && !addr->prop.utf8_downcvt
970 ? "MAIL FROM:<%s>%s%s SMTPUTF8\r\n"
971 :
972 #endif
973 "MAIL FROM:<%s>%s%s\r\n",
974 from_address, responsebuffer, size_str) >= 0)
975 ) &&
976
977 smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer),
978 '2', callout);
979
980 deliver_host = deliver_host_address = NULL;
981 deliver_domain = save_deliver_domain;
982
983 /* If the host does not accept MAIL FROM:<>, arrange to cache this
984 information, but again, don't record anything for an I/O error or a defer. Do
985 not cache rejections of MAIL when a non-empty sender has been used, because
986 that blocks the whole domain for all senders. */
987
988 if (!done)
989 {
990 *failure_ptr = US"mail"; /* At or before MAIL */
991 if (errno == 0 && responsebuffer[0] == '5')
992 {
993 setflag(addr, af_verify_nsfail);
994 if (from_address[0] == 0)
995 new_domain_record.result = ccache_reject_mfnull;
996 }
997 }
998
999 /* Otherwise, proceed to check a "random" address (if required), then the
1000 given address, and the postmaster address (if required). Between each check,
1001 issue RSET, because some servers accept only one recipient after MAIL
1002 FROM:<>.
1003
1004 Before doing this, set the result in the domain cache record to "accept",
1005 unless its previous value was ccache_reject_mfnull. In that case, the domain
1006 rejects MAIL FROM:<> and we want to continue to remember that. When that is
1007 the case, we have got here only in the case of a recipient verification with
1008 a non-null sender. */
1009
1010 else
1011 {
1012 const uschar * rcpt_domain = addr->domain;
1013
1014 #ifdef SUPPORT_I18N
1015 uschar * errstr = NULL;
1016 if ( testflag(addr, af_utf8_downcvt)
1017 && (rcpt_domain = string_domain_utf8_to_alabel(rcpt_domain,
1018 &errstr), errstr)
1019 )
1020 {
1021 addr->message = errstr;
1022 errno = ERRNO_EXPANDFAIL;
1023 setflag(addr, af_verify_nsfail);
1024 done = FALSE;
1025 rcpt_domain = US""; /*XXX errorhandling! */
1026 }
1027 #endif
1028
1029 new_domain_record.result =
1030 (old_domain_cache_result == ccache_reject_mfnull)?
1031 ccache_reject_mfnull: ccache_accept;
1032
1033 /* Do the random local part check first */
1034
1035 if (random_local_part != NULL)
1036 {
1037 uschar randombuffer[1024];
1038 BOOL random_ok =
1039 smtp_write_command(&outblock, FALSE,
1040 "RCPT TO:<%.1000s@%.1000s>\r\n", random_local_part,
1041 rcpt_domain) >= 0 &&
1042 smtp_read_response(&inblock, randombuffer,
1043 sizeof(randombuffer), '2', callout);
1044
1045 /* Remember when we last did a random test */
1046
1047 new_domain_record.random_stamp = time(NULL);
1048
1049 /* If accepted, we aren't going to do any further tests below. */
1050
1051 if (random_ok)
1052 new_domain_record.random_result = ccache_accept;
1053
1054 /* Otherwise, cache a real negative response, and get back to the right
1055 state to send RCPT. Unless there's some problem such as a dropped
1056 connection, we expect to succeed, because the commands succeeded above.
1057 However, some servers drop the connection after responding to an
1058 invalid recipient, so on (any) error we drop and remake the connection.
1059 */
1060
1061 else if (errno == 0)
1062 {
1063 /* This would be ok for 1st rcpt a cutthrough, but no way to
1064 handle a subsequent. So refuse to support any */
1065 cancel_cutthrough_connection("random-recipient");
1066
1067 if (randombuffer[0] == '5')
1068 new_domain_record.random_result = ccache_reject;
1069
1070 done =
1071 smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0 &&
1072 smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer),
1073 '2', callout) &&
1074
1075 smtp_write_command(&outblock, FALSE,
1076 #ifdef SUPPORT_I18N
1077 addr->prop.utf8_msg && !addr->prop.utf8_downcvt
1078 ? "MAIL FROM:<%s> SMTPUTF8\r\n"
1079 :
1080 #endif
1081 "MAIL FROM:<%s>\r\n",
1082 from_address) >= 0 &&
1083 smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer),
1084 '2', callout);
1085
1086 if (!done)
1087 {
1088 HDEBUG(D_acl|D_v)
1089 debug_printf("problem after random/rset/mfrom; reopen conn\n");
1090 random_local_part = NULL;
1091 #ifdef SUPPORT_TLS
1092 tls_close(FALSE, TRUE);
1093 #endif
1094 (void)close(inblock.sock);
1095 #ifndef DISABLE_EVENT
1096 (void) event_raise(addr->transport->event_action,
1097 US"tcp:close", NULL);
1098 #endif
1099 goto tls_retry_connection;
1100 }
1101 }
1102 else done = FALSE; /* Some timeout/connection problem */
1103 } /* Random check */
1104
1105 /* If the host is accepting all local parts, as determined by the "random"
1106 check, we don't need to waste time doing any further checking. */
1107
1108 if (new_domain_record.random_result != ccache_accept && done)
1109 {
1110 /* Get the rcpt_include_affixes flag from the transport if there is one,
1111 but assume FALSE if there is not. */
1112
1113 uschar * rcpt = transport_rcpt_address(addr,
1114 addr->transport ? addr->transport->rcpt_include_affixes : FALSE);
1115
1116 #ifdef SUPPORT_I18N
1117 /*XXX should the conversion be moved into transport_rcpt_address() ? */
1118 uschar * dummy_errstr = NULL;
1119 if ( testflag(addr, af_utf8_downcvt)
1120 && (rcpt = string_address_utf8_to_alabel(rcpt, &dummy_errstr),
1121 dummy_errstr
1122 ) )
1123 {
1124 errno = ERRNO_EXPANDFAIL;
1125 *failure_ptr = US"recipient";
1126 done = FALSE;
1127 }
1128 else
1129 #endif
1130
1131 done =
1132 smtp_write_command(&outblock, FALSE, "RCPT TO:<%.1000s>\r\n",
1133 rcpt) >= 0 &&
1134 smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer),
1135 '2', callout);
1136
1137 if (done)
1138 new_address_record.result = ccache_accept;
1139 else if (errno == 0 && responsebuffer[0] == '5')
1140 {
1141 *failure_ptr = US"recipient";
1142 new_address_record.result = ccache_reject;
1143 }
1144
1145 /* Do postmaster check if requested; if a full check is required, we
1146 check for RCPT TO:<postmaster> (no domain) in accordance with RFC 821. */
1147
1148 if (done && pm_mailfrom != NULL)
1149 {
1150 /* Could possibly shift before main verify, just above, and be ok
1151 for cutthrough. But no way to handle a subsequent rcpt, so just
1152 refuse any */
1153 cancel_cutthrough_connection("postmaster verify");
1154 HDEBUG(D_acl|D_v) debug_printf("Cutthrough cancelled by presence of postmaster verify\n");
1155
1156 done =
1157 smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0 &&
1158 smtp_read_response(&inblock, responsebuffer,
1159 sizeof(responsebuffer), '2', callout) &&
1160
1161 smtp_write_command(&outblock, FALSE,
1162 "MAIL FROM:<%s>\r\n", pm_mailfrom) >= 0 &&
1163 smtp_read_response(&inblock, responsebuffer,
1164 sizeof(responsebuffer), '2', callout) &&
1165
1166 /* First try using the current domain */
1167
1168 ((
1169 smtp_write_command(&outblock, FALSE,
1170 "RCPT TO:<postmaster@%.1000s>\r\n", rcpt_domain) >= 0 &&
1171 smtp_read_response(&inblock, responsebuffer,
1172 sizeof(responsebuffer), '2', callout)
1173 )
1174
1175 ||
1176
1177 /* If that doesn't work, and a full check is requested,
1178 try without the domain. */
1179
1180 (
1181 (options & vopt_callout_fullpm) != 0 &&
1182 smtp_write_command(&outblock, FALSE,
1183 "RCPT TO:<postmaster>\r\n") >= 0 &&
1184 smtp_read_response(&inblock, responsebuffer,
1185 sizeof(responsebuffer), '2', callout)
1186 ));
1187
1188 /* Sort out the cache record */
1189
1190 new_domain_record.postmaster_stamp = time(NULL);
1191
1192 if (done)
1193 new_domain_record.postmaster_result = ccache_accept;
1194 else if (errno == 0 && responsebuffer[0] == '5')
1195 {
1196 *failure_ptr = US"postmaster";
1197 setflag(addr, af_verify_pmfail);
1198 new_domain_record.postmaster_result = ccache_reject;
1199 }
1200 }
1201 } /* Random not accepted */
1202 } /* MAIL FROM: accepted */
1203
1204 /* For any failure of the main check, other than a negative response, we just
1205 close the connection and carry on. We can identify a negative response by the
1206 fact that errno is zero. For I/O errors it will be non-zero
1207
1208 Set up different error texts for logging and for sending back to the caller
1209 as an SMTP response. Log in all cases, using a one-line format. For sender
1210 callouts, give a full response to the caller, but for recipient callouts,
1211 don't give the IP address because this may be an internal host whose identity
1212 is not to be widely broadcast. */
1213
1214 if (!done)
1215 {
1216 if (errno == ETIMEDOUT)
1217 {
1218 HDEBUG(D_verify) debug_printf("SMTP timeout\n");
1219 send_quit = FALSE;
1220 }
1221 #ifdef SUPPORT_I18N
1222 else if (errno == ERRNO_UTF8_FWD)
1223 {
1224 extern int acl_where; /* src/acl.c */
1225 errno = 0;
1226 addr->message = string_sprintf(
1227 "response to \"%s\" from %s [%s] did not include SMTPUTF8",
1228 big_buffer, host->name, host->address);
1229 addr->user_message = acl_where == ACL_WHERE_RCPT
1230 ? US"533 mailbox name not allowed"
1231 : US"550 mailbox unavailable";
1232 yield = FAIL;
1233 done = TRUE;
1234 }
1235 #endif
1236 else if (errno == 0)
1237 {
1238 if (*responsebuffer == 0) Ustrcpy(responsebuffer, US"connection dropped");
1239
1240 addr->message =
1241 string_sprintf("response to \"%s\" from %s [%s] was: %s",
1242 big_buffer, host->name, host->address,
1243 string_printing(responsebuffer));
1244
1245 addr->user_message = options & vopt_is_recipient
1246 ? string_sprintf("Callout verification failed:\n%s", responsebuffer)
1247 : string_sprintf("Called: %s\nSent: %s\nResponse: %s",
1248 host->address, big_buffer, responsebuffer);
1249
1250 /* Hard rejection ends the process */
1251
1252 if (responsebuffer[0] == '5') /* Address rejected */
1253 {
1254 yield = FAIL;
1255 done = TRUE;
1256 }
1257 }
1258 }
1259
1260 /* End the SMTP conversation and close the connection. */
1261
1262 /* Cutthrough - on a successfull connect and recipient-verify with
1263 use-sender and we are 1st rcpt and have no cutthrough conn so far
1264 here is where we want to leave the conn open */
1265 if ( cutthrough.delivery
1266 && rcpt_count == 1
1267 && done
1268 && yield == OK
1269 && (options & (vopt_callout_recipsender|vopt_callout_recippmaster)) == vopt_callout_recipsender
1270 && !random_local_part
1271 && !pm_mailfrom
1272 && cutthrough.fd < 0
1273 && !lmtp
1274 )
1275 {
1276 HDEBUG(D_acl|D_v) debug_printf("holding verify callout open for cutthrough delivery\n");
1277
1278 cutthrough.fd = outblock.sock; /* We assume no buffer in use in the outblock */
1279 cutthrough.nrcpt = 1;
1280 cutthrough.interface = interface;
1281 cutthrough.host = *host;
1282 cutthrough.addr = *addr; /* Save the address_item for later logging */
1283 cutthrough.addr.next = NULL;
1284 cutthrough.addr.host_used = &cutthrough.host;
1285 if (addr->parent)
1286 *(cutthrough.addr.parent = store_get(sizeof(address_item))) =
1287 *addr->parent;
1288 ctblock.buffer = ctbuffer;
1289 ctblock.buffersize = sizeof(ctbuffer);
1290 ctblock.ptr = ctbuffer;
1291 /* ctblock.cmd_count = 0; ctblock.authenticating = FALSE; */
1292 ctblock.sock = cutthrough.fd;
1293 }
1294 else
1295 {
1296 /* Ensure no cutthrough on multiple address verifies */
1297 if (options & vopt_callout_recipsender)
1298 cancel_cutthrough_connection("multiple verify calls");
1299 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
1300
1301 #ifdef SUPPORT_TLS
1302 tls_close(FALSE, TRUE);
1303 #endif
1304 (void)close(inblock.sock);
1305 #ifndef DISABLE_EVENT
1306 (void) event_raise(addr->transport->event_action, US"tcp:close", NULL);
1307 #endif
1308 }
1309
1310 } /* Loop through all hosts, while !done */
1311 }
1312
1313 /* If we get here with done == TRUE, a successful callout happened, and yield
1314 will be set OK or FAIL according to the response to the RCPT command.
1315 Otherwise, we looped through the hosts but couldn't complete the business.
1316 However, there may be domain-specific information to cache in both cases.
1317
1318 The value of the result field in the new_domain record is ccache_unknown if
1319 there was an error before or with MAIL FROM:, and errno was not zero,
1320 implying some kind of I/O error. We don't want to write the cache in that case.
1321 Otherwise the value is ccache_accept, ccache_reject, or ccache_reject_mfnull. */
1322
1323 if ( !(options & vopt_callout_no_cache)
1324 && new_domain_record.result != ccache_unknown)
1325 {
1326 if ((dbm_file = dbfn_open(US"callout", O_RDWR|O_CREAT, &dbblock, FALSE))
1327 == NULL)
1328 {
1329 HDEBUG(D_verify) debug_printf("callout cache: not available\n");
1330 }
1331 else
1332 {
1333 (void)dbfn_write(dbm_file, addr->domain, &new_domain_record,
1334 (int)sizeof(dbdata_callout_cache));
1335 HDEBUG(D_verify) debug_printf("wrote callout cache domain record for %s:\n"
1336 " result=%d postmaster=%d random=%d\n",
1337 addr->domain,
1338 new_domain_record.result,
1339 new_domain_record.postmaster_result,
1340 new_domain_record.random_result);
1341 }
1342 }
1343
1344 /* If a definite result was obtained for the callout, cache it unless caching
1345 is disabled. */
1346
1347 if (done)
1348 {
1349 if ( !(options & vopt_callout_no_cache)
1350 && new_address_record.result != ccache_unknown)
1351 {
1352 if (dbm_file == NULL)
1353 dbm_file = dbfn_open(US"callout", O_RDWR|O_CREAT, &dbblock, FALSE);
1354 if (dbm_file == NULL)
1355 {
1356 HDEBUG(D_verify) debug_printf("no callout cache available\n");
1357 }
1358 else
1359 {
1360 (void)dbfn_write(dbm_file, address_key, &new_address_record,
1361 (int)sizeof(dbdata_callout_cache_address));
1362 HDEBUG(D_verify) debug_printf("wrote %s callout cache address record for %s\n",
1363 new_address_record.result == ccache_accept ? "positive" : "negative",
1364 address_key);
1365 }
1366 }
1367 } /* done */
1368
1369 /* Failure to connect to any host, or any response other than 2xx or 5xx is a
1370 temporary error. If there was only one host, and a response was received, leave
1371 it alone if supplying details. Otherwise, give a generic response. */
1372
1373 else /* !done */
1374 {
1375 uschar *dullmsg = string_sprintf("Could not complete %s verify callout",
1376 options & vopt_is_recipient ? "recipient" : "sender");
1377 yield = DEFER;
1378
1379 if (host_list->next != NULL || addr->message == NULL) addr->message = dullmsg;
1380
1381 addr->user_message = (!smtp_return_error_details)? dullmsg :
1382 string_sprintf("%s for <%s>.\n"
1383 "The mail server(s) for the domain may be temporarily unreachable, or\n"
1384 "they may be permanently unreachable from this server. In the latter case,\n%s",
1385 dullmsg, addr->address,
1386 options & vopt_is_recipient
1387 ? "the address will never be accepted."
1388 : "you need to change the address or create an MX record for its domain\n"
1389 "if it is supposed to be generally accessible from the Internet.\n"
1390 "Talk to your mail administrator for details.");
1391
1392 /* Force a specific error code */
1393
1394 addr->basic_errno = ERRNO_CALLOUTDEFER;
1395 }
1396
1397 /* Come here from within the cache-reading code on fast-track exit. */
1398
1399 END_CALLOUT:
1400 if (dbm_file != NULL) dbfn_close(dbm_file);
1401 return yield;
1402 }
1403
1404
1405
1406 /* Called after recipient-acl to get a cutthrough connection open when
1407 one was requested and a recipient-verify wasn't subsequently done.
1408 */
1409 int
1410 open_cutthrough_connection( address_item * addr )
1411 {
1412 address_item addr2;
1413 int rc;
1414
1415 /* Use a recipient-verify-callout to set up the cutthrough connection. */
1416 /* We must use a copy of the address for verification, because it might
1417 get rewritten. */
1418
1419 addr2 = *addr;
1420 HDEBUG(D_acl) debug_printf("----------- %s cutthrough setup ------------\n",
1421 rcpt_count > 1 ? "more" : "start");
1422 rc= verify_address(&addr2, NULL,
1423 vopt_is_recipient | vopt_callout_recipsender | vopt_callout_no_cache,
1424 CUTTHROUGH_CMD_TIMEOUT, -1, -1,
1425 NULL, NULL, NULL);
1426 HDEBUG(D_acl) debug_printf("----------- end cutthrough setup ------------\n");
1427 return rc;
1428 }
1429
1430
1431
1432 /* Send given number of bytes from the buffer */
1433 static BOOL
1434 cutthrough_send(int n)
1435 {
1436 if(cutthrough.fd < 0)
1437 return TRUE;
1438
1439 if(
1440 #ifdef SUPPORT_TLS
1441 (tls_out.active == cutthrough.fd) ? tls_write(FALSE, ctblock.buffer, n) :
1442 #endif
1443 send(cutthrough.fd, ctblock.buffer, n, 0) > 0
1444 )
1445 {
1446 transport_count += n;
1447 ctblock.ptr= ctblock.buffer;
1448 return TRUE;
1449 }
1450
1451 HDEBUG(D_transport|D_acl) debug_printf("cutthrough_send failed: %s\n", strerror(errno));
1452 return FALSE;
1453 }
1454
1455
1456
1457 static BOOL
1458 _cutthrough_puts(uschar * cp, int n)
1459 {
1460 while(n--)
1461 {
1462 if(ctblock.ptr >= ctblock.buffer+ctblock.buffersize)
1463 if(!cutthrough_send(ctblock.buffersize))
1464 return FALSE;
1465
1466 *ctblock.ptr++ = *cp++;
1467 }
1468 return TRUE;
1469 }
1470
1471 /* Buffered output of counted data block. Return boolean success */
1472 BOOL
1473 cutthrough_puts(uschar * cp, int n)
1474 {
1475 if (cutthrough.fd < 0) return TRUE;
1476 if (_cutthrough_puts(cp, n)) return TRUE;
1477 cancel_cutthrough_connection("transmit failed");
1478 return FALSE;
1479 }
1480
1481
1482 static BOOL
1483 _cutthrough_flush_send(void)
1484 {
1485 int n= ctblock.ptr-ctblock.buffer;
1486
1487 if(n>0)
1488 if(!cutthrough_send(n))
1489 return FALSE;
1490 return TRUE;
1491 }
1492
1493
1494 /* Send out any bufferred output. Return boolean success. */
1495 BOOL
1496 cutthrough_flush_send(void)
1497 {
1498 if (_cutthrough_flush_send()) return TRUE;
1499 cancel_cutthrough_connection("transmit failed");
1500 return FALSE;
1501 }
1502
1503
1504 BOOL
1505 cutthrough_put_nl(void)
1506 {
1507 return cutthrough_puts(US"\r\n", 2);
1508 }
1509
1510
1511 /* Get and check response from cutthrough target */
1512 static uschar
1513 cutthrough_response(char expect, uschar ** copy)
1514 {
1515 smtp_inblock inblock;
1516 uschar inbuffer[4096];
1517 uschar responsebuffer[4096];
1518
1519 inblock.buffer = inbuffer;
1520 inblock.buffersize = sizeof(inbuffer);
1521 inblock.ptr = inbuffer;
1522 inblock.ptrend = inbuffer;
1523 inblock.sock = cutthrough.fd;
1524 /* this relies on (inblock.sock == tls_out.active) */
1525 if(!smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer), expect, CUTTHROUGH_DATA_TIMEOUT))
1526 cancel_cutthrough_connection("target timeout on read");
1527
1528 if(copy != NULL)
1529 {
1530 uschar * cp;
1531 *copy = cp = string_copy(responsebuffer);
1532 /* Trim the trailing end of line */
1533 cp += Ustrlen(responsebuffer);
1534 if(cp > *copy && cp[-1] == '\n') *--cp = '\0';
1535 if(cp > *copy && cp[-1] == '\r') *--cp = '\0';
1536 }
1537
1538 return responsebuffer[0];
1539 }
1540
1541
1542 /* Negotiate dataphase with the cutthrough target, returning success boolean */
1543 BOOL
1544 cutthrough_predata(void)
1545 {
1546 if(cutthrough.fd < 0)
1547 return FALSE;
1548
1549 HDEBUG(D_transport|D_acl|D_v) debug_printf(" SMTP>> DATA\n");
1550 cutthrough_puts(US"DATA\r\n", 6);
1551 cutthrough_flush_send();
1552
1553 /* Assume nothing buffered. If it was it gets ignored. */
1554 return cutthrough_response('3', NULL) == '3';
1555 }
1556
1557
1558 /* fd and use_crlf args only to match write_chunk() */
1559 static BOOL
1560 cutthrough_write_chunk(int fd, uschar * s, int len, BOOL use_crlf)
1561 {
1562 uschar * s2;
1563 while(s && (s2 = Ustrchr(s, '\n')))
1564 {
1565 if(!cutthrough_puts(s, s2-s) || !cutthrough_put_nl())
1566 return FALSE;
1567 s = s2+1;
1568 }
1569 return TRUE;
1570 }
1571
1572
1573 /* Buffered send of headers. Return success boolean. */
1574 /* Expands newlines to wire format (CR,NL). */
1575 /* Also sends header-terminating blank line. */
1576 BOOL
1577 cutthrough_headers_send(void)
1578 {
1579 if(cutthrough.fd < 0)
1580 return FALSE;
1581
1582 /* We share a routine with the mainline transport to handle header add/remove/rewrites,
1583 but having a separate buffered-output function (for now)
1584 */
1585 HDEBUG(D_acl) debug_printf("----------- start cutthrough headers send -----------\n");
1586
1587 if (!transport_headers_send(&cutthrough.addr, cutthrough.fd,
1588 cutthrough.addr.transport->add_headers,
1589 cutthrough.addr.transport->remove_headers,
1590 &cutthrough_write_chunk, TRUE,
1591 cutthrough.addr.transport->rewrite_rules,
1592 cutthrough.addr.transport->rewrite_existflags))
1593 return FALSE;
1594
1595 HDEBUG(D_acl) debug_printf("----------- done cutthrough headers send ------------\n");
1596 return TRUE;
1597 }
1598
1599
1600 static void
1601 close_cutthrough_connection(const char * why)
1602 {
1603 if(cutthrough.fd >= 0)
1604 {
1605 /* We could be sending this after a bunch of data, but that is ok as
1606 the only way to cancel the transfer in dataphase is to drop the tcp
1607 conn before the final dot.
1608 */
1609 ctblock.ptr = ctbuffer;
1610 HDEBUG(D_transport|D_acl|D_v) debug_printf(" SMTP>> QUIT\n");
1611 _cutthrough_puts(US"QUIT\r\n", 6); /* avoid recursion */
1612 _cutthrough_flush_send();
1613 /* No wait for response */
1614
1615 #ifdef SUPPORT_TLS
1616 tls_close(FALSE, TRUE);
1617 #endif
1618 (void)close(cutthrough.fd);
1619 cutthrough.fd = -1;
1620 HDEBUG(D_acl) debug_printf("----------- cutthrough shutdown (%s) ------------\n", why);
1621 }
1622 ctblock.ptr = ctbuffer;
1623 }
1624
1625 void
1626 cancel_cutthrough_connection(const char * why)
1627 {
1628 close_cutthrough_connection(why);
1629 cutthrough.delivery = FALSE;
1630 }
1631
1632
1633
1634
1635 /* Have senders final-dot. Send one to cutthrough target, and grab the response.
1636 Log an OK response as a transmission.
1637 Close the connection.
1638 Return smtp response-class digit.
1639 */
1640 uschar *
1641 cutthrough_finaldot(void)
1642 {
1643 uschar res;
1644 address_item * addr;
1645 HDEBUG(D_transport|D_acl|D_v) debug_printf(" SMTP>> .\n");
1646
1647 /* Assume data finshed with new-line */
1648 if( !cutthrough_puts(US".", 1)
1649 || !cutthrough_put_nl()
1650 || !cutthrough_flush_send()
1651 )
1652 return cutthrough.addr.message;
1653
1654 res = cutthrough_response('2', &cutthrough.addr.message);
1655 for (addr = &cutthrough.addr; addr; addr = addr->next)
1656 {
1657 addr->message = cutthrough.addr.message;
1658 switch(res)
1659 {
1660 case '2':
1661 delivery_log(LOG_MAIN, addr, (int)'>', NULL);
1662 close_cutthrough_connection("delivered");
1663 break;
1664
1665 case '4':
1666 delivery_log(LOG_MAIN, addr, 0,
1667 US"tmp-reject from cutthrough after DATA:");
1668 break;
1669
1670 case '5':
1671 delivery_log(LOG_MAIN|LOG_REJECT, addr, 0,
1672 US"rejected after DATA:");
1673 break;
1674
1675 default:
1676 break;
1677 }
1678 }
1679 return cutthrough.addr.message;
1680 }
1681
1682
1683
1684 /*************************************************
1685 * Copy error to toplevel address *
1686 *************************************************/
1687
1688 /* This function is used when a verify fails or defers, to ensure that the
1689 failure or defer information is in the original toplevel address. This applies
1690 when an address is redirected to a single new address, and the failure or
1691 deferral happens to the child address.
1692
1693 Arguments:
1694 vaddr the verify address item
1695 addr the final address item
1696 yield FAIL or DEFER
1697
1698 Returns: the value of YIELD
1699 */
1700
1701 static int
1702 copy_error(address_item *vaddr, address_item *addr, int yield)
1703 {
1704 if (addr != vaddr)
1705 {
1706 vaddr->message = addr->message;
1707 vaddr->user_message = addr->user_message;
1708 vaddr->basic_errno = addr->basic_errno;
1709 vaddr->more_errno = addr->more_errno;
1710 vaddr->prop.address_data = addr->prop.address_data;
1711 copyflag(vaddr, addr, af_pass_message);
1712 }
1713 return yield;
1714 }
1715
1716
1717
1718
1719 /**************************************************
1720 * printf that automatically handles TLS if needed *
1721 ***************************************************/
1722
1723 /* This function is used by verify_address() as a substitute for all fprintf()
1724 calls; a direct fprintf() will not produce output in a TLS SMTP session, such
1725 as a response to an EXPN command. smtp_in.c makes smtp_printf available but
1726 that assumes that we always use the smtp_out FILE* when not using TLS or the
1727 ssl buffer when we are. Instead we take a FILE* parameter and check to see if
1728 that is smtp_out; if so, smtp_printf() with TLS support, otherwise regular
1729 fprintf().
1730
1731 Arguments:
1732 f the candidate FILE* to write to
1733 format format string
1734 ... optional arguments
1735
1736 Returns:
1737 nothing
1738 */
1739
1740 static void PRINTF_FUNCTION(2,3)
1741 respond_printf(FILE *f, const char *format, ...)
1742 {
1743 va_list ap;
1744
1745 va_start(ap, format);
1746 if (smtp_out && (f == smtp_out))
1747 smtp_vprintf(format, ap);
1748 else
1749 vfprintf(f, format, ap);
1750 va_end(ap);
1751 }
1752
1753
1754
1755 /*************************************************
1756 * Verify an email address *
1757 *************************************************/
1758
1759 /* This function is used both for verification (-bv and at other times) and
1760 address testing (-bt), which is indicated by address_test_mode being set.
1761
1762 Arguments:
1763 vaddr contains the address to verify; the next field in this block
1764 must be NULL
1765 f if not NULL, write the result to this file
1766 options various option bits:
1767 vopt_fake_sender => this sender verify is not for the real
1768 sender (it was verify=sender=xxxx or an address from a
1769 header line) - rewriting must not change sender_address
1770 vopt_is_recipient => this is a recipient address, otherwise
1771 it's a sender address - this affects qualification and
1772 rewriting and messages from callouts
1773 vopt_qualify => qualify an unqualified address; else error
1774 vopt_expn => called from SMTP EXPN command
1775 vopt_success_on_redirect => when a new address is generated
1776 the verification instantly succeeds
1777
1778 These ones are used by do_callout() -- the options variable
1779 is passed to it.
1780
1781 vopt_callout_fullpm => if postmaster check, do full one
1782 vopt_callout_no_cache => don't use callout cache
1783 vopt_callout_random => do the "random" thing
1784 vopt_callout_recipsender => use real sender for recipient
1785 vopt_callout_recippmaster => use postmaster for recipient
1786
1787 callout if > 0, specifies that callout is required, and gives timeout
1788 for individual commands
1789 callout_overall if > 0, gives overall timeout for the callout function;
1790 if < 0, a default is used (see do_callout())
1791 callout_connect the connection timeout for callouts
1792 se_mailfrom when callout is requested to verify a sender, use this
1793 in MAIL FROM; NULL => ""
1794 pm_mailfrom when callout is requested, if non-NULL, do the postmaster
1795 thing and use this as the sender address (may be "")
1796
1797 routed if not NULL, set TRUE if routing succeeded, so we can
1798 distinguish between routing failed and callout failed
1799
1800 Returns: OK address verified
1801 FAIL address failed to verify
1802 DEFER can't tell at present
1803 */
1804
1805 int
1806 verify_address(address_item *vaddr, FILE *f, int options, int callout,
1807 int callout_overall, int callout_connect, uschar *se_mailfrom,
1808 uschar *pm_mailfrom, BOOL *routed)
1809 {
1810 BOOL allok = TRUE;
1811 BOOL full_info = (f == NULL)? FALSE : (debug_selector != 0);
1812 BOOL expn = (options & vopt_expn) != 0;
1813 BOOL success_on_redirect = (options & vopt_success_on_redirect) != 0;
1814 int i;
1815 int yield = OK;
1816 int verify_type = expn? v_expn :
1817 address_test_mode? v_none :
1818 options & vopt_is_recipient? v_recipient : v_sender;
1819 address_item *addr_list;
1820 address_item *addr_new = NULL;
1821 address_item *addr_remote = NULL;
1822 address_item *addr_local = NULL;
1823 address_item *addr_succeed = NULL;
1824 uschar **failure_ptr = options & vopt_is_recipient
1825 ? &recipient_verify_failure : &sender_verify_failure;
1826 uschar *ko_prefix, *cr;
1827 uschar *address = vaddr->address;
1828 uschar *save_sender;
1829 uschar null_sender[] = { 0 }; /* Ensure writeable memory */
1830
1831 /* Clear, just in case */
1832
1833 *failure_ptr = NULL;
1834
1835 /* Set up a prefix and suffix for error message which allow us to use the same
1836 output statements both in EXPN mode (where an SMTP response is needed) and when
1837 debugging with an output file. */
1838
1839 if (expn)
1840 {
1841 ko_prefix = US"553 ";
1842 cr = US"\r";
1843 }
1844 else ko_prefix = cr = US"";
1845
1846 /* Add qualify domain if permitted; otherwise an unqualified address fails. */
1847
1848 if (parse_find_at(address) == NULL)
1849 {
1850 if ((options & vopt_qualify) == 0)
1851 {
1852 if (f != NULL)
1853 respond_printf(f, "%sA domain is required for \"%s\"%s\n",
1854 ko_prefix, address, cr);
1855 *failure_ptr = US"qualify";
1856 return FAIL;
1857 }
1858 address = rewrite_address_qualify(address, options & vopt_is_recipient);
1859 }
1860
1861 DEBUG(D_verify)
1862 {
1863 debug_printf(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
1864 debug_printf("%s %s\n", address_test_mode? "Testing" : "Verifying", address);
1865 }
1866
1867 /* Rewrite and report on it. Clear the domain and local part caches - these
1868 may have been set by domains and local part tests during an ACL. */
1869
1870 if (global_rewrite_rules != NULL)
1871 {
1872 uschar *old = address;
1873 address = rewrite_address(address, options & vopt_is_recipient, FALSE,
1874 global_rewrite_rules, rewrite_existflags);
1875 if (address != old)
1876 {
1877 for (i = 0; i < (MAX_NAMED_LIST * 2)/32; i++) vaddr->localpart_cache[i] = 0;
1878 for (i = 0; i < (MAX_NAMED_LIST * 2)/32; i++) vaddr->domain_cache[i] = 0;
1879 if (f != NULL && !expn) fprintf(f, "Address rewritten as: %s\n", address);
1880 }
1881 }
1882
1883 /* If this is the real sender address, we must update sender_address at
1884 this point, because it may be referred to in the routers. */
1885
1886 if ((options & (vopt_fake_sender|vopt_is_recipient)) == 0)
1887 sender_address = address;
1888
1889 /* If the address was rewritten to <> no verification can be done, and we have
1890 to return OK. This rewriting is permitted only for sender addresses; for other
1891 addresses, such rewriting fails. */
1892
1893 if (address[0] == 0) return OK;
1894
1895 /* Flip the legacy TLS-related variables over to the outbound set in case
1896 they're used in the context of a transport used by verification. Reset them
1897 at exit from this routine (so no returns allowed from here on). */
1898
1899 tls_modify_variables(&tls_out);
1900
1901 /* Save a copy of the sender address for re-instating if we change it to <>
1902 while verifying a sender address (a nice bit of self-reference there). */
1903
1904 save_sender = sender_address;
1905
1906 /* Observability variable for router/transport use */
1907
1908 verify_mode = options & vopt_is_recipient ? US"R" : US"S";
1909
1910 /* Update the address structure with the possibly qualified and rewritten
1911 address. Set it up as the starting address on the chain of new addresses. */
1912
1913 vaddr->address = address;
1914 addr_new = vaddr;
1915
1916 /* We need a loop, because an address can generate new addresses. We must also
1917 cope with generated pipes and files at the top level. (See also the code and
1918 comment in deliver.c.) However, it is usually the case that the router for
1919 user's .forward files has its verify flag turned off.
1920
1921 If an address generates more than one child, the loop is used only when
1922 full_info is set, and this can only be set locally. Remote enquiries just get
1923 information about the top level address, not anything that it generated. */
1924
1925 while (addr_new)
1926 {
1927 int rc;
1928 address_item *addr = addr_new;
1929
1930 addr_new = addr->next;
1931 addr->next = NULL;
1932
1933 DEBUG(D_verify)
1934 {
1935 debug_printf(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
1936 debug_printf("Considering %s\n", addr->address);
1937 }
1938
1939 /* Handle generated pipe, file or reply addresses. We don't get these
1940 when handling EXPN, as it does only one level of expansion. */
1941
1942 if (testflag(addr, af_pfr))
1943 {
1944 allok = FALSE;
1945 if (f != NULL)
1946 {
1947 BOOL allow;
1948
1949 if (addr->address[0] == '>')
1950 {
1951 allow = testflag(addr, af_allow_reply);
1952 fprintf(f, "%s -> mail %s", addr->parent->address, addr->address + 1);
1953 }
1954 else
1955 {
1956 allow = (addr->address[0] == '|')?
1957 testflag(addr, af_allow_pipe) : testflag(addr, af_allow_file);
1958 fprintf(f, "%s -> %s", addr->parent->address, addr->address);
1959 }
1960
1961 if (addr->basic_errno == ERRNO_BADTRANSPORT)
1962 fprintf(f, "\n*** Error in setting up pipe, file, or autoreply:\n"
1963 "%s\n", addr->message);
1964 else if (allow)
1965 fprintf(f, "\n transport = %s\n", addr->transport->name);
1966 else
1967 fprintf(f, " *** forbidden ***\n");
1968 }
1969 continue;
1970 }
1971
1972 /* Just in case some router parameter refers to it. */
1973
1974 return_path = addr->prop.errors_address
1975 ? addr->prop.errors_address : sender_address;
1976
1977 /* Split the address into domain and local part, handling the %-hack if
1978 necessary, and then route it. While routing a sender address, set
1979 $sender_address to <> because that is what it will be if we were trying to
1980 send a bounce to the sender. */
1981
1982 if (routed) *routed = FALSE;
1983 if ((rc = deliver_split_address(addr)) == OK)
1984 {
1985 if (!(options & vopt_is_recipient)) sender_address = null_sender;
1986 rc = route_address(addr, &addr_local, &addr_remote, &addr_new,
1987 &addr_succeed, verify_type);
1988 sender_address = save_sender; /* Put back the real sender */
1989 }
1990
1991 /* If routing an address succeeded, set the flag that remembers, for use when
1992 an ACL cached a sender verify (in case a callout fails). Then if routing set
1993 up a list of hosts or the transport has a host list, and the callout option
1994 is set, and we aren't in a host checking run, do the callout verification,
1995 and set another flag that notes that a callout happened. */
1996
1997 if (rc == OK)
1998 {
1999 if (routed) *routed = TRUE;
2000 if (callout > 0)
2001 {
2002 transport_instance * tp;
2003 host_item * host_list = addr->host_list;
2004
2005 /* Make up some data for use in the case where there is no remote
2006 transport. */
2007
2008 transport_feedback tf = {
2009 NULL, /* interface (=> any) */
2010 US"smtp", /* port */
2011 US"smtp", /* protocol */
2012 NULL, /* hosts */
2013 US"$smtp_active_hostname", /* helo_data */
2014 FALSE, /* hosts_override */
2015 FALSE, /* hosts_randomize */
2016 FALSE, /* gethostbyname */
2017 TRUE, /* qualify_single */
2018 FALSE /* search_parents */
2019 };
2020
2021 /* If verification yielded a remote transport, we want to use that
2022 transport's options, so as to mimic what would happen if we were really
2023 sending a message to this address. */
2024
2025 if ((tp = addr->transport) && !tp->info->local)
2026 {
2027 (void)(tp->setup)(tp, addr, &tf, 0, 0, NULL);
2028
2029 /* If the transport has hosts and the router does not, or if the
2030 transport is configured to override the router's hosts, we must build a
2031 host list of the transport's hosts, and find the IP addresses */
2032
2033 if (tf.hosts && (!host_list || tf.hosts_override))
2034 {
2035 uschar *s;
2036 const uschar *save_deliver_domain = deliver_domain;
2037 uschar *save_deliver_localpart = deliver_localpart;
2038
2039 host_list = NULL; /* Ignore the router's hosts */
2040
2041 deliver_domain = addr->domain;
2042 deliver_localpart = addr->local_part;
2043 s = expand_string(tf.hosts);
2044 deliver_domain = save_deliver_domain;
2045 deliver_localpart = save_deliver_localpart;
2046
2047 if (!s)
2048 {
2049 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand list of hosts "
2050 "\"%s\" in %s transport for callout: %s", tf.hosts,
2051 tp->name, expand_string_message);
2052 }
2053 else
2054 {
2055 int flags;
2056 host_item *host, *nexthost;
2057 host_build_hostlist(&host_list, s, tf.hosts_randomize);
2058
2059 /* Just ignore failures to find a host address. If we don't manage
2060 to find any addresses, the callout will defer. Note that more than
2061 one address may be found for a single host, which will result in
2062 additional host items being inserted into the chain. Hence we must
2063 save the next host first. */
2064
2065 flags = HOST_FIND_BY_A;
2066 if (tf.qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
2067 if (tf.search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
2068
2069 for (host = host_list; host; host = nexthost)
2070 {
2071 nexthost = host->next;
2072 if (tf.gethostbyname ||
2073 string_is_ip_address(host->name, NULL) != 0)
2074 (void)host_find_byname(host, NULL, flags, NULL, TRUE);
2075 else
2076 {
2077 dnssec_domains * dnssec_domains = NULL;
2078 if (Ustrcmp(tp->driver_name, "smtp") == 0)
2079 {
2080 smtp_transport_options_block * ob =
2081 (smtp_transport_options_block *) tp->options_block;
2082 dnssec_domains = &ob->dnssec;
2083 }
2084
2085 (void)host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
2086 dnssec_domains, NULL, NULL);
2087 }
2088 }
2089 }
2090 }
2091 }
2092
2093 /* Can only do a callout if we have at least one host! If the callout
2094 fails, it will have set ${sender,recipient}_verify_failure. */
2095
2096 if (host_list)
2097 {
2098 HDEBUG(D_verify) debug_printf("Attempting full verification using callout\n");
2099 if (host_checking && !host_checking_callout)
2100 {
2101 HDEBUG(D_verify)
2102 debug_printf("... callout omitted by default when host testing\n"
2103 "(Use -bhc if you want the callouts to happen.)\n");
2104 }
2105 else
2106 {
2107 #ifdef SUPPORT_TLS
2108 deliver_set_expansions(addr);
2109 #endif
2110 rc = do_callout(addr, host_list, &tf, callout, callout_overall,
2111 callout_connect, options, se_mailfrom, pm_mailfrom);
2112 }
2113 }
2114 else
2115 {
2116 HDEBUG(D_verify) debug_printf("Cannot do callout: neither router nor "
2117 "transport provided a host list\n");
2118 }
2119 }
2120 }
2121
2122 /* Otherwise, any failure is a routing failure */
2123
2124 else *failure_ptr = US"route";
2125
2126 /* A router may return REROUTED if it has set up a child address as a result
2127 of a change of domain name (typically from widening). In this case we always
2128 want to continue to verify the new child. */
2129
2130 if (rc == REROUTED) continue;
2131
2132 /* Handle hard failures */
2133
2134 if (rc == FAIL)
2135 {
2136 allok = FALSE;
2137 if (f)
2138 {
2139 address_item *p = addr->parent;
2140
2141 respond_printf(f, "%s%s %s", ko_prefix,
2142 full_info ? addr->address : address,
2143 address_test_mode ? "is undeliverable" : "failed to verify");
2144 if (!expn && admin_user)
2145 {
2146 if (addr->basic_errno > 0)
2147 respond_printf(f, ": %s", strerror(addr->basic_errno));
2148 if (addr->message)
2149 respond_printf(f, ": %s", addr->message);
2150 }
2151
2152 /* Show parents iff doing full info */
2153
2154 if (full_info) while (p)
2155 {
2156 respond_printf(f, "%s\n <-- %s", cr, p->address);
2157 p = p->parent;
2158 }
2159 respond_printf(f, "%s\n", cr);
2160 }
2161 cancel_cutthrough_connection("routing hard fail");
2162
2163 if (!full_info)
2164 {
2165 yield = copy_error(vaddr, addr, FAIL);
2166 goto out;
2167 }
2168 yield = FAIL;
2169 }
2170
2171 /* Soft failure */
2172
2173 else if (rc == DEFER)
2174 {
2175 allok = FALSE;
2176 if (f)
2177 {
2178 address_item *p = addr->parent;
2179 respond_printf(f, "%s%s cannot be resolved at this time", ko_prefix,
2180 full_info? addr->address : address);
2181 if (!expn && admin_user)
2182 {
2183 if (addr->basic_errno > 0)
2184 respond_printf(f, ": %s", strerror(addr->basic_errno));
2185 if (addr->message)
2186 respond_printf(f, ": %s", addr->message);
2187 else if (addr->basic_errno <= 0)
2188 respond_printf(f, ": unknown error");
2189 }
2190
2191 /* Show parents iff doing full info */
2192
2193 if (full_info) while (p)
2194 {
2195 respond_printf(f, "%s\n <-- %s", cr, p->address);
2196 p = p->parent;
2197 }
2198 respond_printf(f, "%s\n", cr);
2199 }
2200 cancel_cutthrough_connection("routing soft fail");
2201
2202 if (!full_info)
2203 {
2204 yield = copy_error(vaddr, addr, DEFER);
2205 goto out;
2206 }
2207 if (yield == OK) yield = DEFER;
2208 }
2209
2210 /* If we are handling EXPN, we do not want to continue to route beyond
2211 the top level (whose address is in "address"). */
2212
2213 else if (expn)
2214 {
2215 uschar *ok_prefix = US"250-";
2216
2217 if (!addr_new)
2218 if (!addr_local && !addr_remote)
2219 respond_printf(f, "250 mail to <%s> is discarded\r\n", address);
2220 else
2221 respond_printf(f, "250 <%s>\r\n", address);
2222
2223 else do
2224 {
2225 address_item *addr2 = addr_new;
2226 addr_new = addr2->next;
2227 if (!addr_new) ok_prefix = US"250 ";
2228 respond_printf(f, "%s<%s>\r\n", ok_prefix, addr2->address);
2229 } while (addr_new);
2230 yield = OK;
2231 goto out;
2232 }
2233
2234 /* Successful routing other than EXPN. */
2235
2236 else
2237 {
2238 /* Handle successful routing when short info wanted. Otherwise continue for
2239 other (generated) addresses. Short info is the operational case. Full info
2240 can be requested only when debug_selector != 0 and a file is supplied.
2241
2242 There is a conflict between the use of aliasing as an alternate email
2243 address, and as a sort of mailing list. If an alias turns the incoming
2244 address into just one address (e.g. J.Caesar->jc44) you may well want to
2245 carry on verifying the generated address to ensure it is valid when
2246 checking incoming mail. If aliasing generates multiple addresses, you
2247 probably don't want to do this. Exim therefore treats the generation of
2248 just a single new address as a special case, and continues on to verify the
2249 generated address. */
2250
2251 if ( !full_info /* Stop if short info wanted AND */
2252 && ( ( !addr_new /* No new address OR */
2253 || addr_new->next /* More than one new address OR */
2254 || testflag(addr_new, af_pfr) /* New address is pfr */
2255 )
2256 || /* OR */
2257 ( addr_new /* At least one new address AND */
2258 && success_on_redirect /* success_on_redirect is set */
2259 ) )
2260 )
2261 {
2262 if (f) fprintf(f, "%s %s\n",
2263 address, address_test_mode ? "is deliverable" : "verified");
2264
2265 /* If we have carried on to verify a child address, we want the value
2266 of $address_data to be that of the child */
2267
2268 vaddr->prop.address_data = addr->prop.address_data;
2269 yield = OK;
2270 goto out;
2271 }
2272 }
2273 } /* Loop for generated addresses */
2274
2275 /* Display the full results of the successful routing, including any generated
2276 addresses. Control gets here only when full_info is set, which requires f not
2277 to be NULL, and this occurs only when a top-level verify is called with the
2278 debugging switch on.
2279
2280 If there are no local and no remote addresses, and there were no pipes, files,
2281 or autoreplies, and there were no errors or deferments, the message is to be
2282 discarded, usually because of the use of :blackhole: in an alias file. */
2283
2284 if (allok && !addr_local && !addr_remote)
2285 {
2286 fprintf(f, "mail to %s is discarded\n", address);
2287 goto out;
2288 }
2289
2290 for (addr_list = addr_local, i = 0; i < 2; addr_list = addr_remote, i++)
2291 while (addr_list)
2292 {
2293 address_item *addr = addr_list;
2294 address_item *p = addr->parent;
2295 transport_instance * tp = addr->transport;
2296
2297 addr_list = addr->next;
2298
2299 fprintf(f, "%s", CS addr->address);
2300 #ifdef EXPERIMENTAL_SRS
2301 if(addr->prop.srs_sender)
2302 fprintf(f, " [srs = %s]", addr->prop.srs_sender);
2303 #endif
2304
2305 /* If the address is a duplicate, show something about it. */
2306
2307 if (!testflag(addr, af_pfr))
2308 {
2309 tree_node *tnode;
2310 if ((tnode = tree_search(tree_duplicates, addr->unique)))
2311 fprintf(f, " [duplicate, would not be delivered]");
2312 else tree_add_duplicate(addr->unique, addr);
2313 }
2314
2315 /* Now show its parents */
2316
2317 for (p = addr->parent; p; p = p->parent)
2318 fprintf(f, "\n <-- %s", p->address);
2319 fprintf(f, "\n ");
2320
2321 /* Show router, and transport */
2322
2323 fprintf(f, "router = %s, transport = %s\n",
2324 addr->router->name, tp ? tp->name : US"unset");
2325
2326 /* Show any hosts that are set up by a router unless the transport
2327 is going to override them; fiddle a bit to get a nice format. */
2328
2329 if (addr->host_list && tp && !tp->overrides_hosts)
2330 {
2331 host_item *h;
2332 int maxlen = 0;
2333 int maxaddlen = 0;
2334 for (h = addr->host_list; h; h = h->next)
2335 { /* get max lengths of host names, addrs */
2336 int len = Ustrlen(h->name);
2337 if (len > maxlen) maxlen = len;
2338 len = h->address ? Ustrlen(h->address) : 7;
2339 if (len > maxaddlen) maxaddlen = len;
2340 }
2341 for (h = addr->host_list; h; h = h->next)
2342 {
2343 fprintf(f, " host %-*s ", maxlen, h->name);
2344
2345 if (h->address)
2346 fprintf(f, "[%s%-*c", h->address, maxaddlen+1 - Ustrlen(h->address), ']');
2347 else if (tp->info->local)
2348 fprintf(f, " %-*s ", maxaddlen, ""); /* Omit [unknown] for local */
2349 else
2350 fprintf(f, "[%s%-*c", "unknown", maxaddlen+1 - 7, ']');
2351
2352 if (h->mx >= 0) fprintf(f, " MX=%d", h->mx);
2353 if (h->port != PORT_NONE) fprintf(f, " port=%d", h->port);
2354 if (running_in_test_harness && h->dnssec == DS_YES) fputs(" AD", f);
2355 if (h->status == hstatus_unusable) fputs(" ** unusable **", f);
2356 fputc('\n', f);
2357 }
2358 }
2359 }
2360
2361 /* Yield will be DEFER or FAIL if any one address has, only for full_info (which is
2362 the -bv or -bt case). */
2363
2364 out:
2365 verify_mode = NULL;
2366 tls_modify_variables(&tls_in);
2367
2368 return yield;
2369 }
2370
2371
2372
2373
2374 /*************************************************
2375 * Check headers for syntax errors *
2376 *************************************************/
2377
2378 /* This function checks those header lines that contain addresses, and verifies
2379 that all the addresses therein are syntactially correct.
2380
2381 Arguments:
2382 msgptr where to put an error message
2383
2384 Returns: OK
2385 FAIL
2386 */
2387
2388 int
2389 verify_check_headers(uschar **msgptr)
2390 {
2391 header_line *h;
2392 uschar *colon, *s;
2393 int yield = OK;
2394
2395 for (h = header_list; h != NULL && yield == OK; h = h->next)
2396 {
2397 if (h->type != htype_from &&
2398 h->type != htype_reply_to &&
2399 h->type != htype_sender &&
2400 h->type != htype_to &&
2401 h->type != htype_cc &&
2402 h->type != htype_bcc)
2403 continue;
2404
2405 colon = Ustrchr(h->text, ':');
2406 s = colon + 1;
2407 while (isspace(*s)) s++;
2408
2409 /* Loop for multiple addresses in the header, enabling group syntax. Note
2410 that we have to reset this after the header has been scanned. */
2411
2412 parse_allow_group = TRUE;
2413
2414 while (*s != 0)
2415 {
2416 uschar *ss = parse_find_address_end(s, FALSE);
2417 uschar *recipient, *errmess;
2418 int terminator = *ss;
2419 int start, end, domain;
2420
2421 /* Temporarily terminate the string at this point, and extract the
2422 operative address within, allowing group syntax. */
2423
2424 *ss = 0;
2425 recipient = parse_extract_address(s,&errmess,&start,&end,&domain,FALSE);
2426 *ss = terminator;
2427
2428 /* Permit an unqualified address only if the message is local, or if the
2429 sending host is configured to be permitted to send them. */
2430
2431 if (recipient != NULL && domain == 0)
2432 {
2433 if (h->type == htype_from || h->type == htype_sender)
2434 {
2435 if (!allow_unqualified_sender) recipient = NULL;
2436 }
2437 else
2438 {
2439 if (!allow_unqualified_recipient) recipient = NULL;
2440 }
2441 if (recipient == NULL) errmess = US"unqualified address not permitted";
2442 }
2443
2444 /* It's an error if no address could be extracted, except for the special
2445 case of an empty address. */
2446
2447 if (recipient == NULL && Ustrcmp(errmess, "empty address") != 0)
2448 {
2449 uschar *verb = US"is";
2450 uschar *t = ss;
2451 uschar *tt = colon;
2452 int len;
2453
2454 /* Arrange not to include any white space at the end in the
2455 error message or the header name. */
2456
2457 while (t > s && isspace(t[-1])) t--;
2458 while (tt > h->text && isspace(tt[-1])) tt--;
2459
2460 /* Add the address that failed to the error message, since in a
2461 header with very many addresses it is sometimes hard to spot
2462 which one is at fault. However, limit the amount of address to
2463 quote - cases have been seen where, for example, a missing double
2464 quote in a humungous To: header creates an "address" that is longer
2465 than string_sprintf can handle. */
2466
2467 len = t - s;
2468 if (len > 1024)
2469 {
2470 len = 1024;
2471 verb = US"begins";
2472 }
2473
2474 /* deconst cast ok as we're passing a non-const to string_printing() */
2475 *msgptr = US string_printing(
2476 string_sprintf("%s: failing address in \"%.*s:\" header %s: %.*s",
2477 errmess, tt - h->text, h->text, verb, len, s));
2478
2479 yield = FAIL;
2480 break; /* Out of address loop */
2481 }
2482
2483 /* Advance to the next address */
2484
2485 s = ss + (terminator? 1:0);
2486 while (isspace(*s)) s++;
2487 } /* Next address */
2488
2489 parse_allow_group = FALSE;
2490 parse_found_group = FALSE;
2491 } /* Next header unless yield has been set FALSE */
2492
2493 return yield;
2494 }
2495
2496
2497 /*************************************************
2498 * Check header names for 8-bit characters *
2499 *************************************************/
2500
2501 /* This function checks for invalid charcters in header names. See
2502 RFC 5322, 2.2. and RFC 6532, 3.
2503
2504 Arguments:
2505 msgptr where to put an error message
2506
2507 Returns: OK
2508 FAIL
2509 */
2510
2511 int
2512 verify_check_header_names_ascii(uschar **msgptr)
2513 {
2514 header_line *h;
2515 uschar *colon, *s;
2516
2517 for (h = header_list; h != NULL; h = h->next)
2518 {
2519 colon = Ustrchr(h->text, ':');
2520 for(s = h->text; s < colon; s++)
2521 {
2522 if ((*s < 33) || (*s > 126))
2523 {
2524 *msgptr = string_sprintf("Invalid character in header \"%.*s\" found",
2525 colon - h->text, h->text);
2526 return FAIL;
2527 }
2528 }
2529 }
2530 return OK;
2531 }
2532
2533 /*************************************************
2534 * Check for blind recipients *
2535 *************************************************/
2536
2537 /* This function checks that every (envelope) recipient is mentioned in either
2538 the To: or Cc: header lines, thus detecting blind carbon copies.
2539
2540 There are two ways of scanning that could be used: either scan the header lines
2541 and tick off the recipients, or scan the recipients and check the header lines.
2542 The original proposed patch did the former, but I have chosen to do the latter,
2543 because (a) it requires no memory and (b) will use fewer resources when there
2544 are many addresses in To: and/or Cc: and only one or two envelope recipients.
2545
2546 Arguments: none
2547 Returns: OK if there are no blind recipients
2548 FAIL if there is at least one blind recipient
2549 */
2550
2551 int
2552 verify_check_notblind(void)
2553 {
2554 int i;
2555 for (i = 0; i < recipients_count; i++)
2556 {
2557 header_line *h;
2558 BOOL found = FALSE;
2559 uschar *address = recipients_list[i].address;
2560
2561 for (h = header_list; !found && h != NULL; h = h->next)
2562 {
2563 uschar *colon, *s;
2564
2565 if (h->type != htype_to && h->type != htype_cc) continue;
2566
2567 colon = Ustrchr(h->text, ':');
2568 s = colon + 1;
2569 while (isspace(*s)) s++;
2570
2571 /* Loop for multiple addresses in the header, enabling group syntax. Note
2572 that we have to reset this after the header has been scanned. */
2573
2574 parse_allow_group = TRUE;
2575
2576 while (*s != 0)
2577 {
2578 uschar *ss = parse_find_address_end(s, FALSE);
2579 uschar *recipient,*errmess;
2580 int terminator = *ss;
2581 int start, end, domain;
2582
2583 /* Temporarily terminate the string at this point, and extract the
2584 operative address within, allowing group syntax. */
2585
2586 *ss = 0;
2587 recipient = parse_extract_address(s,&errmess,&start,&end,&domain,FALSE);
2588 *ss = terminator;
2589
2590 /* If we found a valid recipient that has a domain, compare it with the
2591 envelope recipient. Local parts are compared case-sensitively, domains
2592 case-insensitively. By comparing from the start with length "domain", we
2593 include the "@" at the end, which ensures that we are comparing the whole
2594 local part of each address. */
2595
2596 if (recipient != NULL && domain != 0)
2597 {
2598 found = Ustrncmp(recipient, address, domain) == 0 &&
2599 strcmpic(recipient + domain, address + domain) == 0;
2600 if (found) break;
2601 }
2602
2603 /* Advance to the next address */
2604
2605 s = ss + (terminator? 1:0);
2606 while (isspace(*s)) s++;
2607 } /* Next address */
2608
2609 parse_allow_group = FALSE;
2610 parse_found_group = FALSE;
2611 } /* Next header (if found is false) */
2612
2613 if (!found) return FAIL;
2614 } /* Next recipient */
2615
2616 return OK;
2617 }
2618
2619
2620
2621 /*************************************************
2622 * Find if verified sender *
2623 *************************************************/
2624
2625 /* Usually, just a single address is verified as the sender of the message.
2626 However, Exim can be made to verify other addresses as well (often related in
2627 some way), and this is useful in some environments. There may therefore be a
2628 chain of such addresses that have previously been tested. This function finds
2629 whether a given address is on the chain.
2630
2631 Arguments: the address to be verified
2632 Returns: pointer to an address item, or NULL
2633 */
2634
2635 address_item *
2636 verify_checked_sender(uschar *sender)
2637 {
2638 address_item *addr;
2639 for (addr = sender_verified_list; addr != NULL; addr = addr->next)
2640 if (Ustrcmp(sender, addr->address) == 0) break;
2641 return addr;
2642 }
2643
2644
2645
2646
2647
2648 /*************************************************
2649 * Get valid header address *
2650 *************************************************/
2651
2652 /* Scan the originator headers of the message, looking for an address that
2653 verifies successfully. RFC 822 says:
2654
2655 o The "Sender" field mailbox should be sent notices of
2656 any problems in transport or delivery of the original
2657 messages. If there is no "Sender" field, then the
2658 "From" field mailbox should be used.
2659
2660 o If the "Reply-To" field exists, then the reply should
2661 go to the addresses indicated in that field and not to
2662 the address(es) indicated in the "From" field.
2663
2664 So we check a Sender field if there is one, else a Reply_to field, else a From
2665 field. As some strange messages may have more than one of these fields,
2666 especially if they are resent- fields, check all of them if there is more than
2667 one.
2668
2669 Arguments:
2670 user_msgptr points to where to put a user error message
2671 log_msgptr points to where to put a log error message
2672 callout timeout for callout check (passed to verify_address())
2673 callout_overall overall callout timeout (ditto)
2674 callout_connect connect callout timeout (ditto)
2675 se_mailfrom mailfrom for verify; NULL => ""
2676 pm_mailfrom sender for pm callout check (passed to verify_address())
2677 options callout options (passed to verify_address())
2678 verrno where to put the address basic_errno
2679
2680 If log_msgptr is set to something without setting user_msgptr, the caller
2681 normally uses log_msgptr for both things.
2682
2683 Returns: result of the verification attempt: OK, FAIL, or DEFER;
2684 FAIL is given if no appropriate headers are found
2685 */
2686
2687 int
2688 verify_check_header_address(uschar **user_msgptr, uschar **log_msgptr,
2689 int callout, int callout_overall, int callout_connect, uschar *se_mailfrom,
2690 uschar *pm_mailfrom, int options, int *verrno)
2691 {
2692 static int header_types[] = { htype_sender, htype_reply_to, htype_from };
2693 BOOL done = FALSE;
2694 int yield = FAIL;
2695 int i;
2696
2697 for (i = 0; i < 3 && !done; i++)
2698 {
2699 header_line *h;
2700 for (h = header_list; h != NULL && !done; h = h->next)
2701 {
2702 int terminator, new_ok;
2703 uschar *s, *ss, *endname;
2704
2705 if (h->type != header_types[i]) continue;
2706 s = endname = Ustrchr(h->text, ':') + 1;
2707
2708 /* Scan the addresses in the header, enabling group syntax. Note that we
2709 have to reset this after the header has been scanned. */
2710
2711 parse_allow_group = TRUE;
2712
2713 while (*s != 0)
2714 {
2715 address_item *vaddr;
2716
2717 while (isspace(*s) || *s == ',') s++;
2718 if (*s == 0) break; /* End of header */
2719
2720 ss = parse_find_address_end(s, FALSE);
2721
2722 /* The terminator is a comma or end of header, but there may be white
2723 space preceding it (including newline for the last address). Move back
2724 past any white space so we can check against any cached envelope sender
2725 address verifications. */
2726
2727 while (isspace(ss[-1])) ss--;
2728 terminator = *ss;
2729 *ss = 0;
2730
2731 HDEBUG(D_verify) debug_printf("verifying %.*s header address %s\n",
2732 (int)(endname - h->text), h->text, s);
2733
2734 /* See if we have already verified this address as an envelope sender,
2735 and if so, use the previous answer. */
2736
2737 vaddr = verify_checked_sender(s);
2738
2739 if (vaddr != NULL && /* Previously checked */
2740 (callout <= 0 || /* No callout needed; OR */
2741 vaddr->special_action > 256)) /* Callout was done */
2742 {
2743 new_ok = vaddr->special_action & 255;
2744 HDEBUG(D_verify) debug_printf("previously checked as envelope sender\n");
2745 *ss = terminator; /* Restore shortened string */
2746 }
2747
2748 /* Otherwise we run the verification now. We must restore the shortened
2749 string before running the verification, so the headers are correct, in
2750 case there is any rewriting. */
2751
2752 else
2753 {
2754 int start, end, domain;
2755 uschar *address = parse_extract_address(s, log_msgptr, &start, &end,
2756 &domain, FALSE);
2757
2758 *ss = terminator;
2759
2760 /* If we found an empty address, just carry on with the next one, but
2761 kill the message. */
2762
2763 if (address == NULL && Ustrcmp(*log_msgptr, "empty address") == 0)
2764 {
2765 *log_msgptr = NULL;
2766 s = ss;
2767 continue;
2768 }
2769
2770 /* If verification failed because of a syntax error, fail this
2771 function, and ensure that the failing address gets added to the error
2772 message. */
2773
2774 if (address == NULL)
2775 {
2776 new_ok = FAIL;
2777 while (ss > s && isspace(ss[-1])) ss--;
2778 *log_msgptr = string_sprintf("syntax error in '%.*s' header when "
2779 "scanning for sender: %s in \"%.*s\"",
2780 endname - h->text, h->text, *log_msgptr, ss - s, s);
2781 yield = FAIL;
2782 done = TRUE;
2783 break;
2784 }
2785
2786 /* Else go ahead with the sender verification. But it isn't *the*
2787 sender of the message, so set vopt_fake_sender to stop sender_address
2788 being replaced after rewriting or qualification. */
2789
2790 else
2791 {
2792 vaddr = deliver_make_addr(address, FALSE);
2793 new_ok = verify_address(vaddr, NULL, options | vopt_fake_sender,
2794 callout, callout_overall, callout_connect, se_mailfrom,
2795 pm_mailfrom, NULL);
2796 }
2797 }
2798
2799 /* We now have the result, either newly found, or cached. If we are
2800 giving out error details, set a specific user error. This means that the
2801 last of these will be returned to the user if all three fail. We do not
2802 set a log message - the generic one below will be used. */
2803
2804 if (new_ok != OK)
2805 {
2806 *verrno = vaddr->basic_errno;
2807 if (smtp_return_error_details)
2808 {
2809 *user_msgptr = string_sprintf("Rejected after DATA: "
2810 "could not verify \"%.*s\" header address\n%s: %s",
2811 endname - h->text, h->text, vaddr->address, vaddr->message);
2812 }
2813 }
2814
2815 /* Success or defer */
2816
2817 if (new_ok == OK)
2818 {
2819 yield = OK;
2820 done = TRUE;
2821 break;
2822 }
2823
2824 if (new_ok == DEFER) yield = DEFER;
2825
2826 /* Move on to any more addresses in the header */
2827
2828 s = ss;
2829 } /* Next address */
2830
2831 parse_allow_group = FALSE;
2832 parse_found_group = FALSE;
2833 } /* Next header, unless done */
2834 } /* Next header type unless done */
2835
2836 if (yield == FAIL && *log_msgptr == NULL)
2837 *log_msgptr = US"there is no valid sender in any header line";
2838
2839 if (yield == DEFER && *log_msgptr == NULL)
2840 *log_msgptr = US"all attempts to verify a sender in a header line deferred";
2841
2842 return yield;
2843 }
2844
2845
2846
2847
2848 /*************************************************
2849 * Get RFC 1413 identification *
2850 *************************************************/
2851
2852 /* Attempt to get an id from the sending machine via the RFC 1413 protocol. If
2853 the timeout is set to zero, then the query is not done. There may also be lists
2854 of hosts and nets which are exempt. To guard against malefactors sending
2855 non-printing characters which could, for example, disrupt a message's headers,
2856 make sure the string consists of printing characters only.
2857
2858 Argument:
2859 port the port to connect to; usually this is IDENT_PORT (113), but when
2860 running in the test harness with -bh a different value is used.
2861
2862 Returns: nothing
2863
2864 Side effect: any received ident value is put in sender_ident (NULL otherwise)
2865 */
2866
2867 void
2868 verify_get_ident(int port)
2869 {
2870 int sock, host_af, qlen;
2871 int received_sender_port, received_interface_port, n;
2872 uschar *p;
2873 uschar buffer[2048];
2874
2875 /* Default is no ident. Check whether we want to do an ident check for this
2876 host. */
2877
2878 sender_ident = NULL;
2879 if (rfc1413_query_timeout <= 0 || verify_check_host(&rfc1413_hosts) != OK)
2880 return;
2881
2882 DEBUG(D_ident) debug_printf("doing ident callback\n");
2883
2884 /* Set up a connection to the ident port of the remote host. Bind the local end
2885 to the incoming interface address. If the sender host address is an IPv6
2886 address, the incoming interface address will also be IPv6. */
2887
2888 host_af = (Ustrchr(sender_host_address, ':') == NULL)? AF_INET : AF_INET6;
2889 sock = ip_socket(SOCK_STREAM, host_af);
2890 if (sock < 0) return;
2891
2892 if (ip_bind(sock, host_af, interface_address, 0) < 0)
2893 {
2894 DEBUG(D_ident) debug_printf("bind socket for ident failed: %s\n",
2895 strerror(errno));
2896 goto END_OFF;
2897 }
2898
2899 if (ip_connect(sock, host_af, sender_host_address, port, rfc1413_query_timeout)
2900 < 0)
2901 {
2902 if (errno == ETIMEDOUT && LOGGING(ident_timeout))
2903 {
2904 log_write(0, LOG_MAIN, "ident connection to %s timed out",
2905 sender_host_address);
2906 }
2907 else
2908 {
2909 DEBUG(D_ident) debug_printf("ident connection to %s failed: %s\n",
2910 sender_host_address, strerror(errno));
2911 }
2912 goto END_OFF;
2913 }
2914
2915 /* Construct and send the query. */
2916
2917 sprintf(CS buffer, "%d , %d\r\n", sender_host_port, interface_port);
2918 qlen = Ustrlen(buffer);
2919 if (send(sock, buffer, qlen, 0) < 0)
2920 {
2921 DEBUG(D_ident) debug_printf("ident send failed: %s\n", strerror(errno));
2922 goto END_OFF;
2923 }
2924
2925 /* Read a response line. We put it into the rest of the buffer, using several
2926 recv() calls if necessary. */
2927
2928 p = buffer + qlen;
2929
2930 for (;;)
2931 {
2932 uschar *pp;
2933 int count;
2934 int size = sizeof(buffer) - (p - buffer);
2935
2936 if (size <= 0) goto END_OFF; /* Buffer filled without seeing \n. */
2937 count = ip_recv(sock, p, size, rfc1413_query_timeout);
2938 if (count <= 0) goto END_OFF; /* Read error or EOF */
2939
2940 /* Scan what we just read, to see if we have reached the terminating \r\n. Be
2941 generous, and accept a plain \n terminator as well. The only illegal
2942 character is 0. */
2943
2944 for (pp = p; pp < p + count; pp++)
2945 {
2946 if (*pp == 0) goto END_OFF; /* Zero octet not allowed */
2947 if (*pp == '\n')
2948 {
2949 if (pp[-1] == '\r') pp--;
2950 *pp = 0;
2951 goto GOT_DATA; /* Break out of both loops */
2952 }
2953 }
2954
2955 /* Reached the end of the data without finding \n. Let the loop continue to
2956 read some more, if there is room. */
2957
2958 p = pp;
2959 }
2960
2961 GOT_DATA:
2962
2963 /* We have received a line of data. Check it carefully. It must start with the
2964 same two port numbers that we sent, followed by data as defined by the RFC. For
2965 example,
2966
2967 12345 , 25 : USERID : UNIX :root
2968
2969 However, the amount of white space may be different to what we sent. In the
2970 "osname" field there may be several sub-fields, comma separated. The data we
2971 actually want to save follows the third colon. Some systems put leading spaces
2972 in it - we discard those. */
2973
2974 if (sscanf(CS buffer + qlen, "%d , %d%n", &received_sender_port,
2975 &received_interface_port, &n) != 2 ||
2976 received_sender_port != sender_host_port ||
2977 received_interface_port != interface_port)
2978 goto END_OFF;
2979
2980 p = buffer + qlen + n;
2981 while(isspace(*p)) p++;
2982 if (*p++ != ':') goto END_OFF;
2983 while(isspace(*p)) p++;
2984 if (Ustrncmp(p, "USERID", 6) != 0) goto END_OFF;
2985 p += 6;
2986 while(isspace(*p)) p++;
2987 if (*p++ != ':') goto END_OFF;
2988 while (*p != 0 && *p != ':') p++;
2989 if (*p++ == 0) goto END_OFF;
2990 while(isspace(*p)) p++;
2991 if (*p == 0) goto END_OFF;
2992
2993 /* The rest of the line is the data we want. We turn it into printing
2994 characters when we save it, so that it cannot mess up the format of any logging
2995 or Received: lines into which it gets inserted. We keep a maximum of 127
2996 characters. The deconst cast is ok as we fed a nonconst to string_printing() */
2997
2998 sender_ident = US string_printing(string_copyn(p, 127));
2999 DEBUG(D_ident) debug_printf("sender_ident = %s\n", sender_ident);
3000
3001 END_OFF:
3002 (void)close(sock);
3003 return;
3004 }
3005
3006
3007
3008
3009 /*************************************************
3010 * Match host to a single host-list item *
3011 *************************************************/
3012
3013 /* This function compares a host (name or address) against a single item
3014 from a host list. The host name gets looked up if it is needed and is not
3015 already known. The function is called from verify_check_this_host() via
3016 match_check_list(), which is why most of its arguments are in a single block.
3017
3018 Arguments:
3019 arg the argument block (see below)
3020 ss the host-list item
3021 valueptr where to pass back looked up data, or NULL
3022 error for error message when returning ERROR
3023
3024 The block contains:
3025 host_name (a) the host name, or
3026 (b) NULL, implying use sender_host_name and
3027 sender_host_aliases, looking them up if required, or
3028 (c) the empty string, meaning that only IP address matches
3029 are permitted
3030 host_address the host address
3031 host_ipv4 the IPv4 address taken from an IPv6 one
3032
3033 Returns: OK matched
3034 FAIL did not match
3035 DEFER lookup deferred
3036 ERROR (a) failed to find the host name or IP address, or
3037 (b) unknown lookup type specified, or
3038 (c) host name encountered when only IP addresses are
3039 being matched
3040 */
3041
3042 int
3043 check_host(void *arg, const uschar *ss, const uschar **valueptr, uschar **error)
3044 {
3045 check_host_block *cb = (check_host_block *)arg;
3046 int mlen = -1;
3047 int maskoffset;
3048 BOOL iplookup = FALSE;
3049 BOOL isquery = FALSE;
3050 BOOL isiponly = cb->host_name != NULL && cb->host_name[0] == 0;
3051 const uschar *t;
3052 uschar *semicolon;
3053 uschar **aliases;
3054
3055 /* Optimize for the special case when the pattern is "*". */
3056
3057 if (*ss == '*' && ss[1] == 0) return OK;
3058
3059 /* If the pattern is empty, it matches only in the case when there is no host -
3060 this can occur in ACL checking for SMTP input using the -bs option. In this
3061 situation, the host address is the empty string. */
3062
3063 if (cb->host_address[0] == 0) return (*ss == 0)? OK : FAIL;
3064 if (*ss == 0) return FAIL;
3065
3066 /* If the pattern is precisely "@" then match against the primary host name,
3067 provided that host name matching is permitted; if it's "@[]" match against the
3068 local host's IP addresses. */
3069
3070 if (*ss == '@')
3071 {
3072 if (ss[1] == 0)
3073 {
3074 if (isiponly) return ERROR;
3075 ss = primary_hostname;
3076 }
3077 else if (Ustrcmp(ss, "@[]") == 0)
3078 {
3079 ip_address_item *ip;
3080 for (ip = host_find_interfaces(); ip != NULL; ip = ip->next)
3081 if (Ustrcmp(ip->address, cb->host_address) == 0) return OK;
3082 return FAIL;
3083 }
3084 }
3085
3086 /* If the pattern is an IP address, optionally followed by a bitmask count, do
3087 a (possibly masked) comparision with the current IP address. */
3088
3089 if (string_is_ip_address(ss, &maskoffset) != 0)
3090 return (host_is_in_net(cb->host_address, ss, maskoffset)? OK : FAIL);
3091
3092 /* The pattern is not an IP address. A common error that people make is to omit
3093 one component of an IPv4 address, either by accident, or believing that, for
3094 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,
3095 which it isn't. (Those applications that do accept 1.2.3 as an IP address
3096 interpret it as 1.2.0.3 because the final component becomes 16-bit - this is an
3097 ancient specification.) To aid in debugging these cases, we give a specific
3098 error if the pattern contains only digits and dots or contains a slash preceded
3099 only by digits and dots (a slash at the start indicates a file name and of
3100 course slashes may be present in lookups, but not preceded only by digits and
3101 dots). */
3102
3103 for (t = ss; isdigit(*t) || *t == '.'; t++);
3104 if (*t == 0 || (*t == '/' && t != ss))
3105 {
3106 *error = US"malformed IPv4 address or address mask";
3107 return ERROR;
3108 }
3109
3110 /* See if there is a semicolon in the pattern */
3111
3112 semicolon = Ustrchr(ss, ';');
3113
3114 /* If we are doing an IP address only match, then all lookups must be IP
3115 address lookups, even if there is no "net-". */
3116
3117 if (isiponly)
3118 {
3119 iplookup = semicolon != NULL;
3120 }
3121
3122 /* Otherwise, if the item is of the form net[n]-lookup;<file|query> then it is
3123 a lookup on a masked IP network, in textual form. We obey this code even if we
3124 have already set iplookup, so as to skip over the "net-" prefix and to set the
3125 mask length. The net- stuff really only applies to single-key lookups where the
3126 key is implicit. For query-style lookups the key is specified in the query.
3127 From release 4.30, the use of net- for query style is no longer needed, but we
3128 retain it for backward compatibility. */
3129
3130 if (Ustrncmp(ss, "net", 3) == 0 && semicolon != NULL)
3131 {
3132 mlen = 0;
3133 for (t = ss + 3; isdigit(*t); t++) mlen = mlen * 10 + *t - '0';
3134 if (mlen == 0 && t == ss+3) mlen = -1; /* No mask supplied */
3135 iplookup = (*t++ == '-');
3136 }
3137 else t = ss;
3138
3139 /* Do the IP address lookup if that is indeed what we have */
3140
3141 if (iplookup)
3142 {
3143 int insize;
3144 int search_type;
3145 int incoming[4];
3146 void *handle;
3147 uschar *filename, *key, *result;
3148 uschar buffer[64];
3149
3150 /* Find the search type */
3151
3152 search_type = search_findtype(t, semicolon - t);
3153
3154 if (search_type < 0) log_write(0, LOG_MAIN|LOG_PANIC_DIE, "%s",
3155 search_error_message);
3156
3157 /* Adjust parameters for the type of lookup. For a query-style lookup, there
3158 is no file name, and the "key" is just the query. For query-style with a file
3159 name, we have to fish the file off the start of the query. For a single-key
3160 lookup, the key is the current IP address, masked appropriately, and
3161 reconverted to text form, with the mask appended. For IPv6 addresses, specify
3162 dot separators instead of colons, except when the lookup type is "iplsearch".
3163 */
3164
3165 if (mac_islookup(search_type, lookup_absfilequery))
3166 {
3167 filename = semicolon + 1;
3168 key = filename;
3169 while (*key != 0 && !isspace(*key)) key++;
3170 filename = string_copyn(filename, key - filename);
3171 while (isspace(*key)) key++;
3172 }
3173 else if (mac_islookup(search_type, lookup_querystyle))
3174 {
3175 filename = NULL;
3176 key = semicolon + 1;
3177 }
3178 else /* Single-key style */
3179 {
3180 int sep = (Ustrcmp(lookup_list[search_type]->name, "iplsearch") == 0)?
3181 ':' : '.';
3182 insize = host_aton(cb->host_address, incoming);
3183 host_mask(insize, incoming, mlen);
3184 (void)host_nmtoa(insize, incoming, mlen, buffer, sep);
3185 key = buffer;
3186 filename = semicolon + 1;
3187 }
3188
3189 /* Now do the actual lookup; note that there is no search_close() because
3190 of the caching arrangements. */
3191
3192 if (!(handle = search_open(filename, search_type, 0, NULL, NULL)))
3193 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "%s", search_error_message);
3194
3195 result = search_find(handle, filename, key, -1, NULL, 0, 0, NULL);
3196 if (valueptr != NULL) *valueptr = result;
3197 return (result != NULL)? OK : search_find_defer? DEFER: FAIL;
3198 }
3199
3200 /* The pattern is not an IP address or network reference of any kind. That is,
3201 it is a host name pattern. If this is an IP only match, there's an error in the
3202 host list. */
3203
3204 if (isiponly)
3205 {
3206 *error = US"cannot match host name in match_ip list";
3207 return ERROR;
3208 }
3209
3210 /* Check the characters of the pattern to see if they comprise only letters,
3211 digits, full stops, and hyphens (the constituents of domain names). Allow
3212 underscores, as they are all too commonly found. Sigh. Also, if
3213 allow_utf8_domains is set, allow top-bit characters. */
3214
3215 for (t = ss; *t != 0; t++)
3216 if (!isalnum(*t) && *t != '.' && *t != '-' && *t != '_' &&
3217 (!allow_utf8_domains || *t < 128)) break;
3218
3219 /* If the pattern is a complete domain name, with no fancy characters, look up
3220 its IP address and match against that. Note that a multi-homed host will add
3221 items to the chain. */
3222
3223 if (*t == 0)
3224 {
3225 int rc;
3226 host_item h;
3227 h.next = NULL;
3228 h.name = ss;
3229 h.address = NULL;
3230 h.mx = MX_NONE;
3231
3232 /* Using byname rather than bydns here means we cannot determine dnssec
3233 status. On the other hand it is unclear how that could be either
3234 propagated up or enforced. */
3235
3236 rc = host_find_byname(&h, NULL, HOST_FIND_QUALIFY_SINGLE, NULL, FALSE);
3237 if (rc == HOST_FOUND || rc == HOST_FOUND_LOCAL)
3238 {
3239 host_item *hh;
3240 for (hh = &h; hh != NULL; hh = hh->next)
3241 {
3242 if (host_is_in_net(hh->address, cb->host_address, 0)) return OK;
3243 }
3244 return FAIL;
3245 }
3246 if (rc == HOST_FIND_AGAIN) return DEFER;
3247 *error = string_sprintf("failed to find IP address for %s", ss);
3248 return ERROR;
3249 }
3250
3251 /* Almost all subsequent comparisons require the host name, and can be done
3252 using the general string matching function. When this function is called for
3253 outgoing hosts, the name is always given explicitly. If it is NULL, it means we
3254 must use sender_host_name and its aliases, looking them up if necessary. */
3255
3256 if (cb->host_name != NULL) /* Explicit host name given */
3257 return match_check_string(cb->host_name, ss, -1, TRUE, TRUE, TRUE,
3258 valueptr);
3259
3260 /* Host name not given; in principle we need the sender host name and its
3261 aliases. However, for query-style lookups, we do not need the name if the
3262 query does not contain $sender_host_name. From release 4.23, a reference to
3263 $sender_host_name causes it to be looked up, so we don't need to do the lookup
3264 on spec. */
3265
3266 if ((semicolon = Ustrchr(ss, ';')) != NULL)
3267 {
3268 const uschar *affix;
3269 int partial, affixlen, starflags, id;
3270
3271 *semicolon = 0;
3272 id = search_findtype_partial(ss, &partial, &affix, &affixlen, &starflags);
3273 *semicolon=';';
3274
3275 if (id < 0) /* Unknown lookup type */
3276 {
3277 log_write(0, LOG_MAIN|LOG_PANIC, "%s in host list item \"%s\"",
3278 search_error_message, ss);
3279 return DEFER;
3280 }
3281 isquery = mac_islookup(id, lookup_querystyle|lookup_absfilequery);
3282 }
3283
3284 if (isquery)
3285 {
3286 switch(match_check_string(US"", ss, -1, TRUE, TRUE, TRUE, valueptr))
3287 {
3288 case OK: return OK;
3289 case DEFER: return DEFER;
3290 default: return FAIL;
3291 }
3292 }
3293
3294 /* Not a query-style lookup; must ensure the host name is present, and then we
3295 do a check on the name and all its aliases. */
3296
3297 if (sender_host_name == NULL)
3298 {
3299 HDEBUG(D_host_lookup)
3300 debug_printf("sender host name required, to match against %s\n", ss);
3301 if (host_lookup_failed || host_name_lookup() != OK)
3302 {
3303 *error = string_sprintf("failed to find host name for %s",
3304 sender_host_address);;
3305 return ERROR;
3306 }
3307 host_build_sender_fullhost();
3308 }
3309
3310 /* Match on the sender host name, using the general matching function */
3311
3312 switch(match_check_string(sender_host_name, ss, -1, TRUE, TRUE, TRUE,
3313 valueptr))
3314 {
3315 case OK: return OK;
3316 case DEFER: return DEFER;
3317 }
3318
3319 /* If there are aliases, try matching on them. */
3320
3321 aliases = sender_host_aliases;
3322 while (*aliases != NULL)
3323 {
3324 switch(match_check_string(*aliases++, ss, -1, TRUE, TRUE, TRUE, valueptr))
3325 {
3326 case OK: return OK;
3327 case DEFER: return DEFER;
3328 }
3329 }
3330 return FAIL;
3331 }
3332
3333
3334
3335
3336 /*************************************************
3337 * Check a specific host matches a host list *
3338 *************************************************/
3339
3340 /* This function is passed a host list containing items in a number of
3341 different formats and the identity of a host. Its job is to determine whether
3342 the given host is in the set of hosts defined by the list. The host name is
3343 passed as a pointer so that it can be looked up if needed and not already
3344 known. This is commonly the case when called from verify_check_host() to check
3345 an incoming connection. When called from elsewhere the host name should usually
3346 be set.
3347
3348 This function is now just a front end to match_check_list(), which runs common
3349 code for scanning a list. We pass it the check_host() function to perform a
3350 single test.
3351
3352 Arguments:
3353 listptr pointer to the host list
3354 cache_bits pointer to cache for named lists, or NULL
3355 host_name the host name or NULL, implying use sender_host_name and
3356 sender_host_aliases, looking them up if required
3357 host_address the IP address
3358 valueptr if not NULL, data from a lookup is passed back here
3359
3360 Returns: OK if the host is in the defined set
3361 FAIL if the host is not in the defined set,
3362 DEFER if a data lookup deferred (not a host lookup)
3363
3364 If the host name was needed in order to make a comparison, and could not be
3365 determined from the IP address, the result is FAIL unless the item
3366 "+allow_unknown" was met earlier in the list, in which case OK is returned. */
3367
3368 int
3369 verify_check_this_host(const uschar **listptr, unsigned int *cache_bits,
3370 const uschar *host_name, const uschar *host_address, const uschar **valueptr)
3371 {
3372 int rc;
3373 unsigned int *local_cache_bits = cache_bits;
3374 const uschar *save_host_address = deliver_host_address;
3375 check_host_block cb;
3376 cb.host_name = host_name;
3377 cb.host_address = host_address;
3378
3379 if (valueptr != NULL) *valueptr = NULL;
3380
3381 /* If the host address starts off ::ffff: it is an IPv6 address in
3382 IPv4-compatible mode. Find the IPv4 part for checking against IPv4
3383 addresses. */
3384
3385 cb.host_ipv4 = (Ustrncmp(host_address, "::ffff:", 7) == 0)?
3386 host_address + 7 : host_address;
3387
3388 /* During the running of the check, put the IP address into $host_address. In
3389 the case of calls from the smtp transport, it will already be there. However,
3390 in other calls (e.g. when testing ignore_target_hosts), it won't. Just to be on
3391 the safe side, any existing setting is preserved, though as I write this
3392 (November 2004) I can't see any cases where it is actually needed. */
3393
3394 deliver_host_address = host_address;
3395 rc = match_check_list(
3396 listptr, /* the list */
3397 0, /* separator character */
3398 &hostlist_anchor, /* anchor pointer */
3399 &local_cache_bits, /* cache pointer */
3400 check_host, /* function for testing */
3401 &cb, /* argument for function */
3402 MCL_HOST, /* type of check */
3403 (host_address == sender_host_address)?
3404 US"host" : host_address, /* text for debugging */
3405 valueptr); /* where to pass back data */
3406 deliver_host_address = save_host_address;
3407 return rc;
3408 }
3409
3410
3411
3412
3413 /*************************************************
3414 * Check the given host item matches a list *
3415 *************************************************/
3416 int
3417 verify_check_given_host(uschar **listptr, host_item *host)
3418 {
3419 return verify_check_this_host(CUSS listptr, NULL, host->name, host->address, NULL);
3420 }
3421
3422 /*************************************************
3423 * Check the remote host matches a list *
3424 *************************************************/
3425
3426 /* This is a front end to verify_check_this_host(), created because checking
3427 the remote host is a common occurrence. With luck, a good compiler will spot
3428 the tail recursion and optimize it. If there's no host address, this is
3429 command-line SMTP input - check against an empty string for the address.
3430
3431 Arguments:
3432 listptr pointer to the host list
3433
3434 Returns: the yield of verify_check_this_host(),
3435 i.e. OK, FAIL, or DEFER
3436 */
3437
3438 int
3439 verify_check_host(uschar **listptr)
3440 {
3441 return verify_check_this_host(CUSS listptr, sender_host_cache, NULL,
3442 (sender_host_address == NULL)? US"" : sender_host_address, NULL);
3443 }
3444
3445
3446
3447
3448
3449 /*************************************************
3450 * Invert an IP address *
3451 *************************************************/
3452
3453 /* Originally just used for DNS xBL lists, now also used for the