Expanded EXPERIMENTAL_TPDA feature
[exim.git] / src / src / verify.c
1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
4
5 /* Copyright (c) University of Cambridge 1995 - 2014 */
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 address_item cutthrough_addr;
18 static smtp_outblock ctblock;
19 uschar ctbuffer[8192];
20
21
22 /* Structure for caching DNSBL lookups */
23
24 typedef struct dnsbl_cache_block {
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
43
44 /*************************************************
45 * Retrieve a callout cache record *
46 *************************************************/
47
48 /* If a record exists, check whether it has expired.
49
50 Arguments:
51 dbm_file an open hints file
52 key the record key
53 type "address" or "domain"
54 positive_expire expire time for positive records
55 negative_expire expire time for negative records
56
57 Returns: the cache record if a non-expired one exists, else NULL
58 */
59
60 static dbdata_callout_cache *
61 get_callout_cache_record(open_db *dbm_file, uschar *key, uschar *type,
62 int positive_expire, int negative_expire)
63 {
64 BOOL negative;
65 int length, expire;
66 time_t now;
67 dbdata_callout_cache *cache_record;
68
69 cache_record = dbfn_read_with_length(dbm_file, key, &length);
70
71 if (cache_record == NULL)
72 {
73 HDEBUG(D_verify) debug_printf("callout cache: no %s record found\n", type);
74 return NULL;
75 }
76
77 /* We treat a record as "negative" if its result field is not positive, or if
78 it is a domain record and the postmaster field is negative. */
79
80 negative = cache_record->result != ccache_accept ||
81 (type[0] == 'd' && cache_record->postmaster_result == ccache_reject);
82 expire = negative? negative_expire : positive_expire;
83 now = time(NULL);
84
85 if (now - cache_record->time_stamp > expire)
86 {
87 HDEBUG(D_verify) debug_printf("callout cache: %s record expired\n", type);
88 return NULL;
89 }
90
91 /* If this is a non-reject domain record, check for the obsolete format version
92 that doesn't have the postmaster and random timestamps, by looking at the
93 length. If so, copy it to a new-style block, replicating the record's
94 timestamp. Then check the additional timestamps. (There's no point wasting
95 effort if connections are rejected.) */
96
97 if (type[0] == 'd' && cache_record->result != ccache_reject)
98 {
99 if (length == sizeof(dbdata_callout_cache_obs))
100 {
101 dbdata_callout_cache *new = store_get(sizeof(dbdata_callout_cache));
102 memcpy(new, cache_record, length);
103 new->postmaster_stamp = new->random_stamp = new->time_stamp;
104 cache_record = new;
105 }
106
107 if (now - cache_record->postmaster_stamp > expire)
108 cache_record->postmaster_result = ccache_unknown;
109
110 if (now - cache_record->random_stamp > expire)
111 cache_record->random_result = ccache_unknown;
112 }
113
114 HDEBUG(D_verify) debug_printf("callout cache: found %s record\n", type);
115 return cache_record;
116 }
117
118
119
120 /*************************************************
121 * Do callout verification for an address *
122 *************************************************/
123
124 /* This function is called from verify_address() when the address has routed to
125 a host list, and a callout has been requested. Callouts are expensive; that is
126 why a cache is used to improve the efficiency.
127
128 Arguments:
129 addr the address that's been routed
130 host_list the list of hosts to try
131 tf the transport feedback block
132
133 ifstring "interface" option from transport, or NULL
134 portstring "port" option from transport, or NULL
135 protocolstring "protocol" option from transport, or NULL
136 callout the per-command callout timeout
137 callout_overall the overall callout timeout (if < 0 use 4*callout)
138 callout_connect the callout connection timeout (if < 0 use callout)
139 options the verification options - these bits are used:
140 vopt_is_recipient => this is a recipient address
141 vopt_callout_no_cache => don't use callout cache
142 vopt_callout_fullpm => if postmaster check, do full one
143 vopt_callout_random => do the "random" thing
144 vopt_callout_recipsender => use real sender for recipient
145 vopt_callout_recippmaster => use postmaster for recipient
146 se_mailfrom MAIL FROM address for sender verify; NULL => ""
147 pm_mailfrom if non-NULL, do the postmaster check with this sender
148
149 Returns: OK/FAIL/DEFER
150 */
151
152 static int
153 do_callout(address_item *addr, host_item *host_list, transport_feedback *tf,
154 int callout, int callout_overall, int callout_connect, int options,
155 uschar *se_mailfrom, uschar *pm_mailfrom)
156 {
157 BOOL is_recipient = (options & vopt_is_recipient) != 0;
158 BOOL callout_no_cache = (options & vopt_callout_no_cache) != 0;
159 BOOL callout_random = (options & vopt_callout_random) != 0;
160
161 int yield = OK;
162 int old_domain_cache_result = ccache_accept;
163 BOOL done = FALSE;
164 uschar *address_key;
165 uschar *from_address;
166 uschar *random_local_part = NULL;
167 uschar *save_deliver_domain = deliver_domain;
168 uschar **failure_ptr = is_recipient?
169 &recipient_verify_failure : &sender_verify_failure;
170 open_db dbblock;
171 open_db *dbm_file = NULL;
172 dbdata_callout_cache new_domain_record;
173 dbdata_callout_cache_address new_address_record;
174 host_item *host;
175 time_t callout_start_time;
176
177 new_domain_record.result = ccache_unknown;
178 new_domain_record.postmaster_result = ccache_unknown;
179 new_domain_record.random_result = ccache_unknown;
180
181 memset(&new_address_record, 0, sizeof(new_address_record));
182
183 /* For a recipient callout, the key used for the address cache record must
184 include the sender address if we are using the real sender in the callout,
185 because that may influence the result of the callout. */
186
187 address_key = addr->address;
188 from_address = US"";
189
190 if (is_recipient)
191 {
192 if ((options & vopt_callout_recipsender) != 0)
193 {
194 address_key = string_sprintf("%s/<%s>", addr->address, sender_address);
195 from_address = sender_address;
196 }
197 else if ((options & vopt_callout_recippmaster) != 0)
198 {
199 address_key = string_sprintf("%s/<postmaster@%s>", addr->address,
200 qualify_domain_sender);
201 from_address = string_sprintf("postmaster@%s", qualify_domain_sender);
202 }
203 }
204
205 /* For a sender callout, we must adjust the key if the mailfrom address is not
206 empty. */
207
208 else
209 {
210 from_address = (se_mailfrom == NULL)? US"" : se_mailfrom;
211 if (from_address[0] != 0)
212 address_key = string_sprintf("%s/<%s>", addr->address, from_address);
213 }
214
215 /* Open the callout cache database, it it exists, for reading only at this
216 stage, unless caching has been disabled. */
217
218 if (callout_no_cache)
219 {
220 HDEBUG(D_verify) debug_printf("callout cache: disabled by no_cache\n");
221 }
222 else if ((dbm_file = dbfn_open(US"callout", O_RDWR, &dbblock, FALSE)) == NULL)
223 {
224 HDEBUG(D_verify) debug_printf("callout cache: not available\n");
225 }
226
227 /* If a cache database is available see if we can avoid the need to do an
228 actual callout by making use of previously-obtained data. */
229
230 if (dbm_file != NULL)
231 {
232 dbdata_callout_cache_address *cache_address_record;
233 dbdata_callout_cache *cache_record = get_callout_cache_record(dbm_file,
234 addr->domain, US"domain",
235 callout_cache_domain_positive_expire,
236 callout_cache_domain_negative_expire);
237
238 /* If an unexpired cache record was found for this domain, see if the callout
239 process can be short-circuited. */
240
241 if (cache_record != NULL)
242 {
243 /* In most cases, if an early command (up to and including MAIL FROM:<>)
244 was rejected, there is no point carrying on. The callout fails. However, if
245 we are doing a recipient verification with use_sender or use_postmaster
246 set, a previous failure of MAIL FROM:<> doesn't count, because this time we
247 will be using a non-empty sender. We have to remember this situation so as
248 not to disturb the cached domain value if this whole verification succeeds
249 (we don't want it turning into "accept"). */
250
251 old_domain_cache_result = cache_record->result;
252
253 if (cache_record->result == ccache_reject ||
254 (*from_address == 0 && cache_record->result == ccache_reject_mfnull))
255 {
256 setflag(addr, af_verify_nsfail);
257 HDEBUG(D_verify)
258 debug_printf("callout cache: domain gave initial rejection, or "
259 "does not accept HELO or MAIL FROM:<>\n");
260 setflag(addr, af_verify_nsfail);
261 addr->user_message = US"(result of an earlier callout reused).";
262 yield = FAIL;
263 *failure_ptr = US"mail";
264 goto END_CALLOUT;
265 }
266
267 /* If a previous check on a "random" local part was accepted, we assume
268 that the server does not do any checking on local parts. There is therefore
269 no point in doing the callout, because it will always be successful. If a
270 random check previously failed, arrange not to do it again, but preserve
271 the data in the new record. If a random check is required but hasn't been
272 done, skip the remaining cache processing. */
273
274 if (callout_random) switch(cache_record->random_result)
275 {
276 case ccache_accept:
277 HDEBUG(D_verify)
278 debug_printf("callout cache: domain accepts random addresses\n");
279 goto END_CALLOUT; /* Default yield is OK */
280
281 case ccache_reject:
282 HDEBUG(D_verify)
283 debug_printf("callout cache: domain rejects random addresses\n");
284 callout_random = FALSE;
285 new_domain_record.random_result = ccache_reject;
286 new_domain_record.random_stamp = cache_record->random_stamp;
287 break;
288
289 default:
290 HDEBUG(D_verify)
291 debug_printf("callout cache: need to check random address handling "
292 "(not cached or cache expired)\n");
293 goto END_CACHE;
294 }
295
296 /* If a postmaster check is requested, but there was a previous failure,
297 there is again no point in carrying on. If a postmaster check is required,
298 but has not been done before, we are going to have to do a callout, so skip
299 remaining cache processing. */
300
301 if (pm_mailfrom != NULL)
302 {
303 if (cache_record->postmaster_result == ccache_reject)
304 {
305 setflag(addr, af_verify_pmfail);
306 HDEBUG(D_verify)
307 debug_printf("callout cache: domain does not accept "
308 "RCPT TO:<postmaster@domain>\n");
309 yield = FAIL;
310 *failure_ptr = US"postmaster";
311 setflag(addr, af_verify_pmfail);
312 addr->user_message = US"(result of earlier verification reused).";
313 goto END_CALLOUT;
314 }
315 if (cache_record->postmaster_result == ccache_unknown)
316 {
317 HDEBUG(D_verify)
318 debug_printf("callout cache: need to check RCPT "
319 "TO:<postmaster@domain> (not cached or cache expired)\n");
320 goto END_CACHE;
321 }
322
323 /* If cache says OK, set pm_mailfrom NULL to prevent a redundant
324 postmaster check if the address itself has to be checked. Also ensure
325 that the value in the cache record is preserved (with its old timestamp).
326 */
327
328 HDEBUG(D_verify) debug_printf("callout cache: domain accepts RCPT "
329 "TO:<postmaster@domain>\n");
330 pm_mailfrom = NULL;
331 new_domain_record.postmaster_result = ccache_accept;
332 new_domain_record.postmaster_stamp = cache_record->postmaster_stamp;
333 }
334 }
335
336 /* We can't give a result based on information about the domain. See if there
337 is an unexpired cache record for this specific address (combined with the
338 sender address if we are doing a recipient callout with a non-empty sender).
339 */
340
341 cache_address_record = (dbdata_callout_cache_address *)
342 get_callout_cache_record(dbm_file,
343 address_key, US"address",
344 callout_cache_positive_expire,
345 callout_cache_negative_expire);
346
347 if (cache_address_record != NULL)
348 {
349 if (cache_address_record->result == ccache_accept)
350 {
351 HDEBUG(D_verify)
352 debug_printf("callout cache: address record is positive\n");
353 }
354 else
355 {
356 HDEBUG(D_verify)
357 debug_printf("callout cache: address record is negative\n");
358 addr->user_message = US"Previous (cached) callout verification failure";
359 *failure_ptr = US"recipient";
360 yield = FAIL;
361 }
362 goto END_CALLOUT;
363 }
364
365 /* Close the cache database while we actually do the callout for real. */
366
367 END_CACHE:
368 dbfn_close(dbm_file);
369 dbm_file = NULL;
370 }
371
372 if (!addr->transport)
373 {
374 HDEBUG(D_verify) debug_printf("cannot callout via null transport\n");
375 }
376 else if (Ustrcmp(addr->transport->driver_name, "smtp") != 0)
377 log_write(0, LOG_MAIN|LOG_PANIC|LOG_CONFIG_FOR, "callout transport '%s': %s is non-smtp",
378 addr->transport->name, addr->transport->driver_name);
379 else
380 {
381 smtp_transport_options_block *ob =
382 (smtp_transport_options_block *)addr->transport->options_block;
383
384 /* The information wasn't available in the cache, so we have to do a real
385 callout and save the result in the cache for next time, unless no_cache is set,
386 or unless we have a previously cached negative random result. If we are to test
387 with a random local part, ensure that such a local part is available. If not,
388 log the fact, but carry on without randomming. */
389
390 if (callout_random && callout_random_local_part != NULL)
391 {
392 random_local_part = expand_string(callout_random_local_part);
393 if (random_local_part == NULL)
394 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand "
395 "callout_random_local_part: %s", expand_string_message);
396 }
397
398 /* Default the connect and overall callout timeouts if not set, and record the
399 time we are starting so that we can enforce it. */
400
401 if (callout_overall < 0) callout_overall = 4 * callout;
402 if (callout_connect < 0) callout_connect = callout;
403 callout_start_time = time(NULL);
404
405 /* Before doing a real callout, if this is an SMTP connection, flush the SMTP
406 output because a callout might take some time. When PIPELINING is active and
407 there are many recipients, the total time for doing lots of callouts can add up
408 and cause the client to time out. So in this case we forgo the PIPELINING
409 optimization. */
410
411 if (smtp_out != NULL && !disable_callout_flush) mac_smtp_fflush();
412
413 /* Now make connections to the hosts and do real callouts. The list of hosts
414 is passed in as an argument. */
415
416 for (host = host_list; host != NULL && !done; host = host->next)
417 {
418 smtp_inblock inblock;
419 smtp_outblock outblock;
420 int host_af;
421 int port = 25;
422 BOOL send_quit = TRUE;
423 uschar *active_hostname = smtp_active_hostname;
424 BOOL lmtp;
425 BOOL smtps;
426 BOOL esmtp;
427 BOOL suppress_tls = FALSE;
428 uschar *interface = NULL; /* Outgoing interface to use; NULL => any */
429 uschar inbuffer[4096];
430 uschar outbuffer[1024];
431 uschar responsebuffer[4096];
432
433 clearflag(addr, af_verify_pmfail); /* postmaster callout flag */
434 clearflag(addr, af_verify_nsfail); /* null sender callout flag */
435
436 /* Skip this host if we don't have an IP address for it. */
437
438 if (host->address == NULL)
439 {
440 DEBUG(D_verify) debug_printf("no IP address for host name %s: skipping\n",
441 host->name);
442 continue;
443 }
444
445 /* Check the overall callout timeout */
446
447 if (time(NULL) - callout_start_time >= callout_overall)
448 {
449 HDEBUG(D_verify) debug_printf("overall timeout for callout exceeded\n");
450 break;
451 }
452
453 /* Set IPv4 or IPv6 */
454
455 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET:AF_INET6;
456
457 /* Expand and interpret the interface and port strings. The latter will not
458 be used if there is a host-specific port (e.g. from a manualroute router).
459 This has to be delayed till now, because they may expand differently for
460 different hosts. If there's a failure, log it, but carry on with the
461 defaults. */
462
463 deliver_host = host->name;
464 deliver_host_address = host->address;
465 deliver_host_port = host->port;
466 deliver_domain = addr->domain;
467
468 if (!smtp_get_interface(tf->interface, host_af, addr, NULL, &interface,
469 US"callout") ||
470 !smtp_get_port(tf->port, addr, &port, US"callout"))
471 log_write(0, LOG_MAIN|LOG_PANIC, "<%s>: %s", addr->address,
472 addr->message);
473
474 /* Set HELO string according to the protocol */
475 lmtp= Ustrcmp(tf->protocol, "lmtp") == 0;
476 smtps= Ustrcmp(tf->protocol, "smtps") == 0;
477
478
479 HDEBUG(D_verify) debug_printf("interface=%s port=%d\n", interface, port);
480
481 /* Set up the buffer for reading SMTP response packets. */
482
483 inblock.buffer = inbuffer;
484 inblock.buffersize = sizeof(inbuffer);
485 inblock.ptr = inbuffer;
486 inblock.ptrend = inbuffer;
487
488 /* Set up the buffer for holding SMTP commands while pipelining */
489
490 outblock.buffer = outbuffer;
491 outblock.buffersize = sizeof(outbuffer);
492 outblock.ptr = outbuffer;
493 outblock.cmd_count = 0;
494 outblock.authenticating = FALSE;
495
496 /* Reset the parameters of a TLS session */
497 tls_out.cipher = tls_out.peerdn = NULL;
498
499 /* Connect to the host; on failure, just loop for the next one, but we
500 set the error for the last one. Use the callout_connect timeout. */
501
502 tls_retry_connection:
503
504 inblock.sock = outblock.sock =
505 smtp_connect(host, host_af, port, interface, callout_connect, TRUE, NULL
506 #ifdef EXPERIMENTAL_TPDA
507 /*XXX tpda action? NULL for now. */
508 , NULL
509 #endif
510 );
511 /* reconsider DSCP here */
512 if (inblock.sock < 0)
513 {
514 addr->message = string_sprintf("could not connect to %s [%s]: %s",
515 host->name, host->address, strerror(errno));
516 deliver_host = deliver_host_address = NULL;
517 deliver_domain = save_deliver_domain;
518 continue;
519 }
520
521 /* Expand the helo_data string to find the host name to use. */
522
523 if (tf->helo_data != NULL)
524 {
525 uschar *s = expand_string(tf->helo_data);
526 if (s == NULL)
527 log_write(0, LOG_MAIN|LOG_PANIC, "<%s>: failed to expand transport's "
528 "helo_data value for callout: %s", addr->address,
529 expand_string_message);
530 else active_hostname = s;
531 }
532
533 /* Wait for initial response, and send HELO. The smtp_write_command()
534 function leaves its command in big_buffer. This is used in error responses.
535 Initialize it in case the connection is rejected. */
536
537 Ustrcpy(big_buffer, "initial connection");
538
539 /* Unless ssl-on-connect, wait for the initial greeting */
540 smtps_redo_greeting:
541
542 #ifdef SUPPORT_TLS
543 if (!smtps || (smtps && tls_out.active >= 0))
544 #endif
545 {
546 if (!(done= smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer), '2', callout)))
547 goto RESPONSE_FAILED;
548
549 #ifdef EXPERIMENTAL_TPDA
550 if (tpda_raise_event(addr->transport->tpda_event_action,
551 US"smtp:connect", responsebuffer) == DEFER)
552 {
553 /* Logging? Debug? */
554 goto RESPONSE_FAILED;
555 }
556 #endif
557 }
558
559 /* Not worth checking greeting line for ESMTP support */
560 if (!(esmtp = verify_check_this_host(&(ob->hosts_avoid_esmtp), NULL,
561 host->name, host->address, NULL) != OK))
562 DEBUG(D_transport)
563 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
564
565 tls_redo_helo:
566
567 #ifdef SUPPORT_TLS
568 if (smtps && tls_out.active < 0) /* ssl-on-connect, first pass */
569 {
570 tls_offered = TRUE;
571 ob->tls_tempfail_tryclear = FALSE;
572 }
573 else /* all other cases */
574 #endif
575
576 { esmtp_retry:
577
578 if (!(done= smtp_write_command(&outblock, FALSE, "%s %s\r\n",
579 !esmtp? "HELO" : lmtp? "LHLO" : "EHLO", active_hostname) >= 0))
580 goto SEND_FAILED;
581 if (!smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer), '2', callout))
582 {
583 if (errno != 0 || responsebuffer[0] == 0 || lmtp || !esmtp || tls_out.active >= 0)
584 {
585 done= FALSE;
586 goto RESPONSE_FAILED;
587 }
588 #ifdef SUPPORT_TLS
589 tls_offered = FALSE;
590 #endif
591 esmtp = FALSE;
592 goto esmtp_retry; /* fallback to HELO */
593 }
594
595 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
596 #ifdef SUPPORT_TLS
597 if (esmtp && !suppress_tls && tls_out.active < 0)
598 {
599 if (regex_STARTTLS == NULL) regex_STARTTLS =
600 regex_must_compile(US"\\n250[\\s\\-]STARTTLS(\\s|\\n|$)", FALSE, TRUE);
601
602 tls_offered = pcre_exec(regex_STARTTLS, NULL, CS responsebuffer,
603 Ustrlen(responsebuffer), 0, PCRE_EOPT, NULL, 0) >= 0;
604 }
605 else
606 tls_offered = FALSE;
607 #endif
608 }
609
610 /* If TLS is available on this connection attempt to
611 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
612 send another EHLO - the server may give a different answer in secure mode. We
613 use a separate buffer for reading the response to STARTTLS so that if it is
614 negative, the original EHLO data is available for subsequent analysis, should
615 the client not be required to use TLS. If the response is bad, copy the buffer
616 for error analysis. */
617
618 #ifdef SUPPORT_TLS
619 if (tls_offered &&
620 verify_check_this_host(&(ob->hosts_avoid_tls), NULL, host->name,
621 host->address, NULL) != OK &&
622 verify_check_this_host(&(ob->hosts_verify_avoid_tls), NULL, host->name,
623 host->address, NULL) != OK
624 )
625 {
626 uschar buffer2[4096];
627 if ( !smtps
628 && !(done= smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") >= 0))
629 goto SEND_FAILED;
630
631 /* If there is an I/O error, transmission of this message is deferred. If
632 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
633 false, we also defer. However, if there is a temporary rejection of STARTTLS
634 and tls_tempfail_tryclear is true, or if there is an outright rejection of
635 STARTTLS, we carry on. This means we will try to send the message in clear,
636 unless the host is in hosts_require_tls (tested below). */
637
638 if (!smtps && !smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
639 ob->command_timeout))
640 {
641 if (errno != 0 || buffer2[0] == 0 ||
642 (buffer2[0] == '4' && !ob->tls_tempfail_tryclear))
643 {
644 Ustrncpy(responsebuffer, buffer2, sizeof(responsebuffer));
645 done= FALSE;
646 goto RESPONSE_FAILED;
647 }
648 }
649
650 /* STARTTLS accepted or ssl-on-connect: try to negotiate a TLS session. */
651 else
652 {
653 int oldtimeout = ob->command_timeout;
654 int rc;
655
656 ob->command_timeout = callout;
657 rc = tls_client_start(inblock.sock, host, addr, addr->transport);
658 ob->command_timeout = oldtimeout;
659
660 /* TLS negotiation failed; give an error. Try in clear on a new connection,
661 if the options permit it for this host. */
662 if (rc != OK)
663 {
664 if (rc == DEFER && ob->tls_tempfail_tryclear && !smtps &&
665 verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
666 host->address, NULL) != OK)
667 {
668 (void)close(inblock.sock);
669 #ifdef EXPERIMENTAL_TPDA
670 (void) tpda_raise_event(addr->transport->tpda_event_action,
671 US"tcp:close", NULL);
672 #endif
673 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
674 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
675 suppress_tls = TRUE;
676 goto tls_retry_connection;
677 }
678 /*save_errno = ERRNO_TLSFAILURE;*/
679 /*message = US"failure while setting up TLS session";*/
680 send_quit = FALSE;
681 done= FALSE;
682 goto TLS_FAILED;
683 }
684
685 /* TLS session is set up. Copy info for logging. */
686 addr->cipher = tls_out.cipher;
687 addr->peerdn = tls_out.peerdn;
688
689 /* For SMTPS we need to wait for the initial OK response, then do HELO. */
690 if (smtps)
691 goto smtps_redo_greeting;
692
693 /* For STARTTLS we need to redo EHLO */
694 goto tls_redo_helo;
695 }
696 }
697
698 /* If the host is required to use a secure channel, ensure that we have one. */
699 if (tls_out.active < 0)
700 if (verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
701 host->address, NULL) == OK)
702 {
703 /*save_errno = ERRNO_TLSREQUIRED;*/
704 log_write(0, LOG_MAIN, "a TLS session is required for %s [%s], but %s",
705 host->name, host->address,
706 tls_offered? "an attempt to start TLS failed" : "the server did not offer TLS support");
707 done= FALSE;
708 goto TLS_FAILED;
709 }
710
711 #endif /*SUPPORT_TLS*/
712
713 done = TRUE; /* so far so good; have response to HELO */
714
715 /*XXX the EHLO response would be analyzed here for IGNOREQUOTA, SIZE, PIPELINING */
716
717 /* For now, transport_filter by cutthrough-delivery is not supported */
718 /* Need proper integration with the proper transport mechanism. */
719 if (cutthrough_delivery)
720 {
721 if (addr->transport->filter_command)
722 {
723 cutthrough_delivery= FALSE;
724 HDEBUG(D_acl|D_v) debug_printf("Cutthrough cancelled by presence of transport filter\n");
725 }
726 #ifndef DISABLE_DKIM
727 if (ob->dkim_domain)
728 {
729 cutthrough_delivery= FALSE;
730 HDEBUG(D_acl|D_v) debug_printf("Cutthrough cancelled by presence of DKIM signing\n");
731 }
732 #endif
733 }
734
735 SEND_FAILED:
736 RESPONSE_FAILED:
737 TLS_FAILED:
738 ;
739 /* Clear down of the TLS, SMTP and TCP layers on error is handled below. */
740
741 /* Failure to accept HELO is cached; this blocks the whole domain for all
742 senders. I/O errors and defer responses are not cached. */
743
744 if (!done)
745 {
746 *failure_ptr = US"mail"; /* At or before MAIL */
747 if (errno == 0 && responsebuffer[0] == '5')
748 {
749 setflag(addr, af_verify_nsfail);
750 new_domain_record.result = ccache_reject;
751 }
752 }
753
754 /* If we haven't authenticated, but are required to, give up. */
755 /* Try to AUTH */
756
757 else done = smtp_auth(responsebuffer, sizeof(responsebuffer),
758 addr, host, ob, esmtp, &inblock, &outblock) == OK &&
759
760 /* Copy AUTH info for logging */
761 ( (addr->authenticator = client_authenticator),
762 (addr->auth_id = client_authenticated_id),
763
764 /* Build a mail-AUTH string (re-using responsebuffer for convenience */
765 !smtp_mail_auth_str(responsebuffer, sizeof(responsebuffer), addr, ob)
766 ) &&
767
768 ( (addr->auth_sndr = client_authenticated_sender),
769
770 /* Send the MAIL command */
771 (smtp_write_command(&outblock, FALSE, "MAIL FROM:<%s>%s\r\n",
772 from_address, responsebuffer) >= 0)
773 ) &&
774
775 smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer),
776 '2', callout);
777
778 deliver_host = deliver_host_address = NULL;
779 deliver_domain = save_deliver_domain;
780
781 /* If the host does not accept MAIL FROM:<>, arrange to cache this
782 information, but again, don't record anything for an I/O error or a defer. Do
783 not cache rejections of MAIL when a non-empty sender has been used, because
784 that blocks the whole domain for all senders. */
785
786 if (!done)
787 {
788 *failure_ptr = US"mail"; /* At or before MAIL */
789 if (errno == 0 && responsebuffer[0] == '5')
790 {
791 setflag(addr, af_verify_nsfail);
792 if (from_address[0] == 0)
793 new_domain_record.result = ccache_reject_mfnull;
794 }
795 }
796
797 /* Otherwise, proceed to check a "random" address (if required), then the
798 given address, and the postmaster address (if required). Between each check,
799 issue RSET, because some servers accept only one recipient after MAIL
800 FROM:<>.
801
802 Before doing this, set the result in the domain cache record to "accept",
803 unless its previous value was ccache_reject_mfnull. In that case, the domain
804 rejects MAIL FROM:<> and we want to continue to remember that. When that is
805 the case, we have got here only in the case of a recipient verification with
806 a non-null sender. */
807
808 else
809 {
810 new_domain_record.result =
811 (old_domain_cache_result == ccache_reject_mfnull)?
812 ccache_reject_mfnull: ccache_accept;
813
814 /* Do the random local part check first */
815
816 if (random_local_part != NULL)
817 {
818 uschar randombuffer[1024];
819 BOOL random_ok =
820 smtp_write_command(&outblock, FALSE,
821 "RCPT TO:<%.1000s@%.1000s>\r\n", random_local_part,
822 addr->domain) >= 0 &&
823 smtp_read_response(&inblock, randombuffer,
824 sizeof(randombuffer), '2', callout);
825
826 /* Remember when we last did a random test */
827
828 new_domain_record.random_stamp = time(NULL);
829
830 /* If accepted, we aren't going to do any further tests below. */
831
832 if (random_ok)
833 {
834 new_domain_record.random_result = ccache_accept;
835 }
836
837 /* Otherwise, cache a real negative response, and get back to the right
838 state to send RCPT. Unless there's some problem such as a dropped
839 connection, we expect to succeed, because the commands succeeded above. */
840
841 else if (errno == 0)
842 {
843 if (randombuffer[0] == '5')
844 new_domain_record.random_result = ccache_reject;
845
846 done =
847 smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0 &&
848 smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer),
849 '2', callout) &&
850
851 smtp_write_command(&outblock, FALSE, "MAIL FROM:<%s>\r\n",
852 from_address) >= 0 &&
853 smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer),
854 '2', callout);
855 }
856 else done = FALSE; /* Some timeout/connection problem */
857 } /* Random check */
858
859 /* If the host is accepting all local parts, as determined by the "random"
860 check, we don't need to waste time doing any further checking. */
861
862 if (new_domain_record.random_result != ccache_accept && done)
863 {
864 /* Get the rcpt_include_affixes flag from the transport if there is one,
865 but assume FALSE if there is not. */
866
867 done =
868 smtp_write_command(&outblock, FALSE, "RCPT TO:<%.1000s>\r\n",
869 transport_rcpt_address(addr,
870 (addr->transport == NULL)? FALSE :
871 addr->transport->rcpt_include_affixes)) >= 0 &&
872 smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer),
873 '2', callout);
874
875 if (done)
876 new_address_record.result = ccache_accept;
877 else if (errno == 0 && responsebuffer[0] == '5')
878 {
879 *failure_ptr = US"recipient";
880 new_address_record.result = ccache_reject;
881 }
882
883 /* Do postmaster check if requested; if a full check is required, we
884 check for RCPT TO:<postmaster> (no domain) in accordance with RFC 821. */
885
886 if (done && pm_mailfrom != NULL)
887 {
888 /*XXX not suitable for cutthrough - sequencing problems */
889 cutthrough_delivery= FALSE;
890 HDEBUG(D_acl|D_v) debug_printf("Cutthrough cancelled by presence of postmaster verify\n");
891
892 done =
893 smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0 &&
894 smtp_read_response(&inblock, responsebuffer,
895 sizeof(responsebuffer), '2', callout) &&
896
897 smtp_write_command(&outblock, FALSE,
898 "MAIL FROM:<%s>\r\n", pm_mailfrom) >= 0 &&
899 smtp_read_response(&inblock, responsebuffer,
900 sizeof(responsebuffer), '2', callout) &&
901
902 /* First try using the current domain */
903
904 ((
905 smtp_write_command(&outblock, FALSE,
906 "RCPT TO:<postmaster@%.1000s>\r\n", addr->domain) >= 0 &&
907 smtp_read_response(&inblock, responsebuffer,
908 sizeof(responsebuffer), '2', callout)
909 )
910
911 ||
912
913 /* If that doesn't work, and a full check is requested,
914 try without the domain. */
915
916 (
917 (options & vopt_callout_fullpm) != 0 &&
918 smtp_write_command(&outblock, FALSE,
919 "RCPT TO:<postmaster>\r\n") >= 0 &&
920 smtp_read_response(&inblock, responsebuffer,
921 sizeof(responsebuffer), '2', callout)
922 ));
923
924 /* Sort out the cache record */
925
926 new_domain_record.postmaster_stamp = time(NULL);
927
928 if (done)
929 new_domain_record.postmaster_result = ccache_accept;
930 else if (errno == 0 && responsebuffer[0] == '5')
931 {
932 *failure_ptr = US"postmaster";
933 setflag(addr, af_verify_pmfail);
934 new_domain_record.postmaster_result = ccache_reject;
935 }
936 }
937 } /* Random not accepted */
938 } /* MAIL FROM: accepted */
939
940 /* For any failure of the main check, other than a negative response, we just
941 close the connection and carry on. We can identify a negative response by the
942 fact that errno is zero. For I/O errors it will be non-zero
943
944 Set up different error texts for logging and for sending back to the caller
945 as an SMTP response. Log in all cases, using a one-line format. For sender
946 callouts, give a full response to the caller, but for recipient callouts,
947 don't give the IP address because this may be an internal host whose identity
948 is not to be widely broadcast. */
949
950 if (!done)
951 {
952 if (errno == ETIMEDOUT)
953 {
954 HDEBUG(D_verify) debug_printf("SMTP timeout\n");
955 send_quit = FALSE;
956 }
957 else if (errno == 0)
958 {
959 if (*responsebuffer == 0) Ustrcpy(responsebuffer, US"connection dropped");
960
961 addr->message =
962 string_sprintf("response to \"%s\" from %s [%s] was: %s",
963 big_buffer, host->name, host->address,
964 string_printing(responsebuffer));
965
966 addr->user_message = is_recipient?
967 string_sprintf("Callout verification failed:\n%s", responsebuffer)
968 :
969 string_sprintf("Called: %s\nSent: %s\nResponse: %s",
970 host->address, big_buffer, responsebuffer);
971
972 /* Hard rejection ends the process */
973
974 if (responsebuffer[0] == '5') /* Address rejected */
975 {
976 yield = FAIL;
977 done = TRUE;
978 }
979 }
980 }
981
982 /* End the SMTP conversation and close the connection. */
983
984 /* Cutthrough - on a successfull connect and recipient-verify with use-sender
985 and we have no cutthrough conn so far
986 here is where we want to leave the conn open */
987 if ( cutthrough_delivery
988 && done
989 && yield == OK
990 && (options & (vopt_callout_recipsender|vopt_callout_recippmaster)) == vopt_callout_recipsender
991 && !random_local_part
992 && !pm_mailfrom
993 && cutthrough_fd < 0
994 )
995 {
996 cutthrough_fd= outblock.sock; /* We assume no buffer in use in the outblock */
997 cutthrough_addr = *addr; /* Save the address_item for later logging */
998 cutthrough_addr.next = NULL;
999 cutthrough_addr.host_used = store_get(sizeof(host_item));
1000 cutthrough_addr.host_used->name = host->name;
1001 cutthrough_addr.host_used->address = host->address;
1002 cutthrough_addr.host_used->port = port;
1003 if (addr->parent)
1004 *(cutthrough_addr.parent = store_get(sizeof(address_item)))= *addr->parent;
1005 ctblock.buffer = ctbuffer;
1006 ctblock.buffersize = sizeof(ctbuffer);
1007 ctblock.ptr = ctbuffer;
1008 /* ctblock.cmd_count = 0; ctblock.authenticating = FALSE; */
1009 ctblock.sock = cutthrough_fd;
1010 }
1011 else
1012 {
1013 /* Ensure no cutthrough on multiple address verifies */
1014 if (options & vopt_callout_recipsender)
1015 cancel_cutthrough_connection("multiple verify calls");
1016 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
1017
1018 #ifdef SUPPORT_TLS
1019 tls_close(FALSE, TRUE);
1020 #endif
1021 (void)close(inblock.sock);
1022 #ifdef EXPERIMENTAL_TPDA
1023 (void) tpda_raise_event(addr->transport->tpda_event_action,
1024 US"tcp:close", NULL);
1025 #endif
1026 }
1027
1028 } /* Loop through all hosts, while !done */
1029 }
1030
1031 /* If we get here with done == TRUE, a successful callout happened, and yield
1032 will be set OK or FAIL according to the response to the RCPT command.
1033 Otherwise, we looped through the hosts but couldn't complete the business.
1034 However, there may be domain-specific information to cache in both cases.
1035
1036 The value of the result field in the new_domain record is ccache_unknown if
1037 there was an error before or with MAIL FROM:, and errno was not zero,
1038 implying some kind of I/O error. We don't want to write the cache in that case.
1039 Otherwise the value is ccache_accept, ccache_reject, or ccache_reject_mfnull. */
1040
1041 if (!callout_no_cache && new_domain_record.result != ccache_unknown)
1042 {
1043 if ((dbm_file = dbfn_open(US"callout", O_RDWR|O_CREAT, &dbblock, FALSE))
1044 == NULL)
1045 {
1046 HDEBUG(D_verify) debug_printf("callout cache: not available\n");
1047 }
1048 else
1049 {
1050 (void)dbfn_write(dbm_file, addr->domain, &new_domain_record,
1051 (int)sizeof(dbdata_callout_cache));
1052 HDEBUG(D_verify) debug_printf("wrote callout cache domain record:\n"
1053 " result=%d postmaster=%d random=%d\n",
1054 new_domain_record.result,
1055 new_domain_record.postmaster_result,
1056 new_domain_record.random_result);
1057 }
1058 }
1059
1060 /* If a definite result was obtained for the callout, cache it unless caching
1061 is disabled. */
1062
1063 if (done)
1064 {
1065 if (!callout_no_cache && new_address_record.result != ccache_unknown)
1066 {
1067 if (dbm_file == NULL)
1068 dbm_file = dbfn_open(US"callout", O_RDWR|O_CREAT, &dbblock, FALSE);
1069 if (dbm_file == NULL)
1070 {
1071 HDEBUG(D_verify) debug_printf("no callout cache available\n");
1072 }
1073 else
1074 {
1075 (void)dbfn_write(dbm_file, address_key, &new_address_record,
1076 (int)sizeof(dbdata_callout_cache_address));
1077 HDEBUG(D_verify) debug_printf("wrote %s callout cache address record\n",
1078 (new_address_record.result == ccache_accept)? "positive" : "negative");
1079 }
1080 }
1081 } /* done */
1082
1083 /* Failure to connect to any host, or any response other than 2xx or 5xx is a
1084 temporary error. If there was only one host, and a response was received, leave
1085 it alone if supplying details. Otherwise, give a generic response. */
1086
1087 else /* !done */
1088 {
1089 uschar *dullmsg = string_sprintf("Could not complete %s verify callout",
1090 is_recipient? "recipient" : "sender");
1091 yield = DEFER;
1092
1093 if (host_list->next != NULL || addr->message == NULL) addr->message = dullmsg;
1094
1095 addr->user_message = (!smtp_return_error_details)? dullmsg :
1096 string_sprintf("%s for <%s>.\n"
1097 "The mail server(s) for the domain may be temporarily unreachable, or\n"
1098 "they may be permanently unreachable from this server. In the latter case,\n%s",
1099 dullmsg, addr->address,
1100 is_recipient?
1101 "the address will never be accepted."
1102 :
1103 "you need to change the address or create an MX record for its domain\n"
1104 "if it is supposed to be generally accessible from the Internet.\n"
1105 "Talk to your mail administrator for details.");
1106
1107 /* Force a specific error code */
1108
1109 addr->basic_errno = ERRNO_CALLOUTDEFER;
1110 }
1111
1112 /* Come here from within the cache-reading code on fast-track exit. */
1113
1114 END_CALLOUT:
1115 if (dbm_file != NULL) dbfn_close(dbm_file);
1116 return yield;
1117 }
1118
1119
1120
1121 /* Called after recipient-acl to get a cutthrough connection open when
1122 one was requested and a recipient-verify wasn't subsequently done.
1123 */
1124 void
1125 open_cutthrough_connection( address_item * addr )
1126 {
1127 address_item addr2;
1128
1129 /* Use a recipient-verify-callout to set up the cutthrough connection. */
1130 /* We must use a copy of the address for verification, because it might
1131 get rewritten. */
1132
1133 addr2 = *addr;
1134 HDEBUG(D_acl) debug_printf("----------- start cutthrough setup ------------\n");
1135 (void) verify_address(&addr2, NULL,
1136 vopt_is_recipient | vopt_callout_recipsender | vopt_callout_no_cache,
1137 CUTTHROUGH_CMD_TIMEOUT, -1, -1,
1138 NULL, NULL, NULL);
1139 HDEBUG(D_acl) debug_printf("----------- end cutthrough setup ------------\n");
1140 return;
1141 }
1142
1143
1144
1145 /* Send given number of bytes from the buffer */
1146 static BOOL
1147 cutthrough_send(int n)
1148 {
1149 if(cutthrough_fd < 0)
1150 return TRUE;
1151
1152 if(
1153 #ifdef SUPPORT_TLS
1154 (tls_out.active == cutthrough_fd) ? tls_write(FALSE, ctblock.buffer, n) :
1155 #endif
1156 send(cutthrough_fd, ctblock.buffer, n, 0) > 0
1157 )
1158 {
1159 transport_count += n;
1160 ctblock.ptr= ctblock.buffer;
1161 return TRUE;
1162 }
1163
1164 HDEBUG(D_transport|D_acl) debug_printf("cutthrough_send failed: %s\n", strerror(errno));
1165 return FALSE;
1166 }
1167
1168
1169
1170 static BOOL
1171 _cutthrough_puts(uschar * cp, int n)
1172 {
1173 while(n--)
1174 {
1175 if(ctblock.ptr >= ctblock.buffer+ctblock.buffersize)
1176 if(!cutthrough_send(ctblock.buffersize))
1177 return FALSE;
1178
1179 *ctblock.ptr++ = *cp++;
1180 }
1181 return TRUE;
1182 }
1183
1184 /* Buffered output of counted data block. Return boolean success */
1185 BOOL
1186 cutthrough_puts(uschar * cp, int n)
1187 {
1188 if (cutthrough_fd < 0) return TRUE;
1189 if (_cutthrough_puts(cp, n)) return TRUE;
1190 cancel_cutthrough_connection("transmit failed");
1191 return FALSE;
1192 }
1193
1194
1195 static BOOL
1196 _cutthrough_flush_send( void )
1197 {
1198 int n= ctblock.ptr-ctblock.buffer;
1199
1200 if(n>0)
1201 if(!cutthrough_send(n))
1202 return FALSE;
1203 return TRUE;
1204 }
1205
1206
1207 /* Send out any bufferred output. Return boolean success. */
1208 BOOL
1209 cutthrough_flush_send( void )
1210 {
1211 if (_cutthrough_flush_send()) return TRUE;
1212 cancel_cutthrough_connection("transmit failed");
1213 return FALSE;
1214 }
1215
1216
1217 BOOL
1218 cutthrough_put_nl( void )
1219 {
1220 return cutthrough_puts(US"\r\n", 2);
1221 }
1222
1223
1224 /* Get and check response from cutthrough target */
1225 static uschar
1226 cutthrough_response(char expect, uschar ** copy)
1227 {
1228 smtp_inblock inblock;
1229 uschar inbuffer[4096];
1230 uschar responsebuffer[4096];
1231
1232 inblock.buffer = inbuffer;
1233 inblock.buffersize = sizeof(inbuffer);
1234 inblock.ptr = inbuffer;
1235 inblock.ptrend = inbuffer;
1236 inblock.sock = cutthrough_fd;
1237 /* this relies on (inblock.sock == tls_out.active) */
1238 if(!smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer), expect, CUTTHROUGH_DATA_TIMEOUT))
1239 cancel_cutthrough_connection("target timeout on read");
1240
1241 if(copy != NULL)
1242 {
1243 uschar * cp;
1244 *copy= cp= string_copy(responsebuffer);
1245 /* Trim the trailing end of line */
1246 cp += Ustrlen(responsebuffer);
1247 if(cp > *copy && cp[-1] == '\n') *--cp = '\0';
1248 if(cp > *copy && cp[-1] == '\r') *--cp = '\0';
1249 }
1250
1251 return responsebuffer[0];
1252 }
1253
1254
1255 /* Negotiate dataphase with the cutthrough target, returning success boolean */
1256 BOOL
1257 cutthrough_predata( void )
1258 {
1259 if(cutthrough_fd < 0)
1260 return FALSE;
1261
1262 HDEBUG(D_transport|D_acl|D_v) debug_printf(" SMTP>> DATA\n");
1263 cutthrough_puts(US"DATA\r\n", 6);
1264 cutthrough_flush_send();
1265
1266 /* Assume nothing buffered. If it was it gets ignored. */
1267 return cutthrough_response('3', NULL) == '3';
1268 }
1269
1270
1271 /* fd and use_crlf args only to match write_chunk() */
1272 static BOOL
1273 cutthrough_write_chunk(int fd, uschar * s, int len, BOOL use_crlf)
1274 {
1275 uschar * s2;
1276 while(s && (s2 = Ustrchr(s, '\n')))
1277 {
1278 if(!cutthrough_puts(s, s2-s) || !cutthrough_put_nl())
1279 return FALSE;
1280 s = s2+1;
1281 }
1282 return TRUE;
1283 }
1284
1285
1286 /* Buffered send of headers. Return success boolean. */
1287 /* Expands newlines to wire format (CR,NL). */
1288 /* Also sends header-terminating blank line. */
1289 BOOL
1290 cutthrough_headers_send( void )
1291 {
1292 if(cutthrough_fd < 0)
1293 return FALSE;
1294
1295 /* We share a routine with the mainline transport to handle header add/remove/rewrites,
1296 but having a separate buffered-output function (for now)
1297 */
1298 HDEBUG(D_acl) debug_printf("----------- start cutthrough headers send -----------\n");
1299
1300 if (!transport_headers_send(&cutthrough_addr, cutthrough_fd,
1301 cutthrough_addr.transport->add_headers, cutthrough_addr.transport->remove_headers,
1302 &cutthrough_write_chunk, TRUE,
1303 cutthrough_addr.transport->rewrite_rules, cutthrough_addr.transport->rewrite_existflags))
1304 return FALSE;
1305
1306 HDEBUG(D_acl) debug_printf("----------- done cutthrough headers send ------------\n");
1307 return TRUE;
1308 }
1309
1310
1311 static void
1312 close_cutthrough_connection( const char * why )
1313 {
1314 if(cutthrough_fd >= 0)
1315 {
1316 /* We could be sending this after a bunch of data, but that is ok as
1317 the only way to cancel the transfer in dataphase is to drop the tcp
1318 conn before the final dot.
1319 */
1320 ctblock.ptr = ctbuffer;
1321 HDEBUG(D_transport|D_acl|D_v) debug_printf(" SMTP>> QUIT\n");
1322 _cutthrough_puts(US"QUIT\r\n", 6); /* avoid recursion */
1323 _cutthrough_flush_send();
1324 /* No wait for response */
1325
1326 #ifdef SUPPORT_TLS
1327 tls_close(FALSE, TRUE);
1328 #endif
1329 (void)close(cutthrough_fd);
1330 cutthrough_fd= -1;
1331 HDEBUG(D_acl) debug_printf("----------- cutthrough shutdown (%s) ------------\n", why);
1332 }
1333 ctblock.ptr = ctbuffer;
1334 }
1335
1336 void
1337 cancel_cutthrough_connection( const char * why )
1338 {
1339 close_cutthrough_connection(why);
1340 cutthrough_delivery= FALSE;
1341 }
1342
1343
1344
1345
1346 /* Have senders final-dot. Send one to cutthrough target, and grab the response.
1347 Log an OK response as a transmission.
1348 Close the connection.
1349 Return smtp response-class digit.
1350 */
1351 uschar *
1352 cutthrough_finaldot( void )
1353 {
1354 HDEBUG(D_transport|D_acl|D_v) debug_printf(" SMTP>> .\n");
1355
1356 /* Assume data finshed with new-line */
1357 if(!cutthrough_puts(US".", 1) || !cutthrough_put_nl() || !cutthrough_flush_send())
1358 return cutthrough_addr.message;
1359
1360 switch(cutthrough_response('2', &cutthrough_addr.message))
1361 {
1362 case '2':
1363 delivery_log(LOG_MAIN, &cutthrough_addr, (int)'>', NULL);
1364 close_cutthrough_connection("delivered");
1365 break;
1366
1367 case '4':
1368 delivery_log(LOG_MAIN, &cutthrough_addr, 0, US"tmp-reject from cutthrough after DATA:");
1369 break;
1370
1371 case '5':
1372 delivery_log(LOG_MAIN|LOG_REJECT, &cutthrough_addr, 0, US"rejected after DATA:");
1373 break;
1374
1375 default:
1376 break;
1377 }
1378 return cutthrough_addr.message;
1379 }
1380
1381
1382
1383 /*************************************************
1384 * Copy error to toplevel address *
1385 *************************************************/
1386
1387 /* This function is used when a verify fails or defers, to ensure that the
1388 failure or defer information is in the original toplevel address. This applies
1389 when an address is redirected to a single new address, and the failure or
1390 deferral happens to the child address.
1391
1392 Arguments:
1393 vaddr the verify address item
1394 addr the final address item
1395 yield FAIL or DEFER
1396
1397 Returns: the value of YIELD
1398 */
1399
1400 static int
1401 copy_error(address_item *vaddr, address_item *addr, int yield)
1402 {
1403 if (addr != vaddr)
1404 {
1405 vaddr->message = addr->message;
1406 vaddr->user_message = addr->user_message;
1407 vaddr->basic_errno = addr->basic_errno;
1408 vaddr->more_errno = addr->more_errno;
1409 vaddr->p.address_data = addr->p.address_data;
1410 copyflag(vaddr, addr, af_pass_message);
1411 }
1412 return yield;
1413 }
1414
1415
1416
1417
1418 /**************************************************
1419 * printf that automatically handles TLS if needed *
1420 ***************************************************/
1421
1422 /* This function is used by verify_address() as a substitute for all fprintf()
1423 calls; a direct fprintf() will not produce output in a TLS SMTP session, such
1424 as a response to an EXPN command. smtp_in.c makes smtp_printf available but
1425 that assumes that we always use the smtp_out FILE* when not using TLS or the
1426 ssl buffer when we are. Instead we take a FILE* parameter and check to see if
1427 that is smtp_out; if so, smtp_printf() with TLS support, otherwise regular
1428 fprintf().
1429
1430 Arguments:
1431 f the candidate FILE* to write to
1432 format format string
1433 ... optional arguments
1434
1435 Returns:
1436 nothing
1437 */
1438
1439 static void PRINTF_FUNCTION(2,3)
1440 respond_printf(FILE *f, const char *format, ...)
1441 {
1442 va_list ap;
1443
1444 va_start(ap, format);
1445 if (smtp_out && (f == smtp_out))
1446 smtp_vprintf(format, ap);
1447 else
1448 vfprintf(f, format, ap);
1449 va_end(ap);
1450 }
1451
1452
1453
1454 /*************************************************
1455 * Verify an email address *
1456 *************************************************/
1457
1458 /* This function is used both for verification (-bv and at other times) and
1459 address testing (-bt), which is indicated by address_test_mode being set.
1460
1461 Arguments:
1462 vaddr contains the address to verify; the next field in this block
1463 must be NULL
1464 f if not NULL, write the result to this file
1465 options various option bits:
1466 vopt_fake_sender => this sender verify is not for the real
1467 sender (it was verify=sender=xxxx or an address from a
1468 header line) - rewriting must not change sender_address
1469 vopt_is_recipient => this is a recipient address, otherwise
1470 it's a sender address - this affects qualification and
1471 rewriting and messages from callouts
1472 vopt_qualify => qualify an unqualified address; else error
1473 vopt_expn => called from SMTP EXPN command
1474 vopt_success_on_redirect => when a new address is generated
1475 the verification instantly succeeds
1476
1477 These ones are used by do_callout() -- the options variable
1478 is passed to it.
1479
1480 vopt_callout_fullpm => if postmaster check, do full one
1481 vopt_callout_no_cache => don't use callout cache
1482 vopt_callout_random => do the "random" thing
1483 vopt_callout_recipsender => use real sender for recipient
1484 vopt_callout_recippmaster => use postmaster for recipient
1485
1486 callout if > 0, specifies that callout is required, and gives timeout
1487 for individual commands
1488 callout_overall if > 0, gives overall timeout for the callout function;
1489 if < 0, a default is used (see do_callout())
1490 callout_connect the connection timeout for callouts
1491 se_mailfrom when callout is requested to verify a sender, use this
1492 in MAIL FROM; NULL => ""
1493 pm_mailfrom when callout is requested, if non-NULL, do the postmaster
1494 thing and use this as the sender address (may be "")
1495
1496 routed if not NULL, set TRUE if routing succeeded, so we can
1497 distinguish between routing failed and callout failed
1498
1499 Returns: OK address verified
1500 FAIL address failed to verify
1501 DEFER can't tell at present
1502 */
1503
1504 int
1505 verify_address(address_item *vaddr, FILE *f, int options, int callout,
1506 int callout_overall, int callout_connect, uschar *se_mailfrom,
1507 uschar *pm_mailfrom, BOOL *routed)
1508 {
1509 BOOL allok = TRUE;
1510 BOOL full_info = (f == NULL)? FALSE : (debug_selector != 0);
1511 BOOL is_recipient = (options & vopt_is_recipient) != 0;
1512 BOOL expn = (options & vopt_expn) != 0;
1513 BOOL success_on_redirect = (options & vopt_success_on_redirect) != 0;
1514 int i;
1515 int yield = OK;
1516 int verify_type = expn? v_expn :
1517 address_test_mode? v_none :
1518 is_recipient? v_recipient : v_sender;
1519 address_item *addr_list;
1520 address_item *addr_new = NULL;
1521 address_item *addr_remote = NULL;
1522 address_item *addr_local = NULL;
1523 address_item *addr_succeed = NULL;
1524 uschar **failure_ptr = is_recipient?
1525 &recipient_verify_failure : &sender_verify_failure;
1526 uschar *ko_prefix, *cr;
1527 uschar *address = vaddr->address;
1528 uschar *save_sender;
1529 uschar null_sender[] = { 0 }; /* Ensure writeable memory */
1530
1531 /* Clear, just in case */
1532
1533 *failure_ptr = NULL;
1534
1535 /* Set up a prefix and suffix for error message which allow us to use the same
1536 output statements both in EXPN mode (where an SMTP response is needed) and when
1537 debugging with an output file. */
1538
1539 if (expn)
1540 {
1541 ko_prefix = US"553 ";
1542 cr = US"\r";
1543 }
1544 else ko_prefix = cr = US"";
1545
1546 /* Add qualify domain if permitted; otherwise an unqualified address fails. */
1547
1548 if (parse_find_at(address) == NULL)
1549 {
1550 if ((options & vopt_qualify) == 0)
1551 {
1552 if (f != NULL)
1553 respond_printf(f, "%sA domain is required for \"%s\"%s\n",
1554 ko_prefix, address, cr);
1555 *failure_ptr = US"qualify";
1556 return FAIL;
1557 }
1558 address = rewrite_address_qualify(address, is_recipient);
1559 }
1560
1561 DEBUG(D_verify)
1562 {
1563 debug_printf(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
1564 debug_printf("%s %s\n", address_test_mode? "Testing" : "Verifying", address);
1565 }
1566
1567 /* Rewrite and report on it. Clear the domain and local part caches - these
1568 may have been set by domains and local part tests during an ACL. */
1569
1570 if (global_rewrite_rules != NULL)
1571 {
1572 uschar *old = address;
1573 address = rewrite_address(address, is_recipient, FALSE,
1574 global_rewrite_rules, rewrite_existflags);
1575 if (address != old)
1576 {
1577 for (i = 0; i < (MAX_NAMED_LIST * 2)/32; i++) vaddr->localpart_cache[i] = 0;
1578 for (i = 0; i < (MAX_NAMED_LIST * 2)/32; i++) vaddr->domain_cache[i] = 0;
1579 if (f != NULL && !expn) fprintf(f, "Address rewritten as: %s\n", address);
1580 }
1581 }
1582
1583 /* If this is the real sender address, we must update sender_address at
1584 this point, because it may be referred to in the routers. */
1585
1586 if ((options & (vopt_fake_sender|vopt_is_recipient)) == 0)
1587 sender_address = address;
1588
1589 /* If the address was rewritten to <> no verification can be done, and we have
1590 to return OK. This rewriting is permitted only for sender addresses; for other
1591 addresses, such rewriting fails. */
1592
1593 if (address[0] == 0) return OK;
1594
1595 /* Flip the legacy TLS-related variables over to the outbound set in case
1596 they're used in the context of a transport used by verification. Reset them
1597 at exit from this routine. */
1598
1599 tls_modify_variables(&tls_out);
1600
1601 /* Save a copy of the sender address for re-instating if we change it to <>
1602 while verifying a sender address (a nice bit of self-reference there). */
1603
1604 save_sender = sender_address;
1605
1606 /* Update the address structure with the possibly qualified and rewritten
1607 address. Set it up as the starting address on the chain of new addresses. */
1608
1609 vaddr->address = address;
1610 addr_new = vaddr;
1611
1612 /* We need a loop, because an address can generate new addresses. We must also
1613 cope with generated pipes and files at the top level. (See also the code and
1614 comment in deliver.c.) However, it is usually the case that the router for
1615 user's .forward files has its verify flag turned off.
1616
1617 If an address generates more than one child, the loop is used only when
1618 full_info is set, and this can only be set locally. Remote enquiries just get
1619 information about the top level address, not anything that it generated. */
1620
1621 while (addr_new != NULL)
1622 {
1623 int rc;
1624 address_item *addr = addr_new;
1625
1626 addr_new = addr->next;
1627 addr->next = NULL;
1628
1629 DEBUG(D_verify)
1630 {
1631 debug_printf(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
1632 debug_printf("Considering %s\n", addr->address);
1633 }
1634
1635 /* Handle generated pipe, file or reply addresses. We don't get these
1636 when handling EXPN, as it does only one level of expansion. */
1637
1638 if (testflag(addr, af_pfr))
1639 {
1640 allok = FALSE;
1641 if (f != NULL)
1642 {
1643 BOOL allow;
1644
1645 if (addr->address[0] == '>')
1646 {
1647 allow = testflag(addr, af_allow_reply);
1648 fprintf(f, "%s -> mail %s", addr->parent->address, addr->address + 1);
1649 }
1650 else
1651 {
1652 allow = (addr->address[0] == '|')?
1653 testflag(addr, af_allow_pipe) : testflag(addr, af_allow_file);
1654 fprintf(f, "%s -> %s", addr->parent->address, addr->address);
1655 }
1656
1657 if (addr->basic_errno == ERRNO_BADTRANSPORT)
1658 fprintf(f, "\n*** Error in setting up pipe, file, or autoreply:\n"
1659 "%s\n", addr->message);
1660 else if (allow)
1661 fprintf(f, "\n transport = %s\n", addr->transport->name);
1662 else
1663 fprintf(f, " *** forbidden ***\n");
1664 }
1665 continue;
1666 }
1667
1668 /* Just in case some router parameter refers to it. */
1669
1670 return_path = (addr->p.errors_address != NULL)?
1671 addr->p.errors_address : sender_address;
1672
1673 /* Split the address into domain and local part, handling the %-hack if
1674 necessary, and then route it. While routing a sender address, set
1675 $sender_address to <> because that is what it will be if we were trying to
1676 send a bounce to the sender. */
1677
1678 if (routed != NULL) *routed = FALSE;
1679 if ((rc = deliver_split_address(addr)) == OK)
1680 {
1681 if (!is_recipient) sender_address = null_sender;
1682 rc = route_address(addr, &addr_local, &addr_remote, &addr_new,
1683 &addr_succeed, verify_type);
1684 sender_address = save_sender; /* Put back the real sender */
1685 }
1686
1687 /* If routing an address succeeded, set the flag that remembers, for use when
1688 an ACL cached a sender verify (in case a callout fails). Then if routing set
1689 up a list of hosts or the transport has a host list, and the callout option
1690 is set, and we aren't in a host checking run, do the callout verification,
1691 and set another flag that notes that a callout happened. */
1692
1693 if (rc == OK)
1694 {
1695 if (routed != NULL) *routed = TRUE;
1696 if (callout > 0)
1697 {
1698 host_item *host_list = addr->host_list;
1699
1700 /* Make up some data for use in the case where there is no remote
1701 transport. */
1702
1703 transport_feedback tf = {
1704 NULL, /* interface (=> any) */
1705 US"smtp", /* port */
1706 US"smtp", /* protocol */
1707 NULL, /* hosts */
1708 US"$smtp_active_hostname", /* helo_data */
1709 FALSE, /* hosts_override */
1710 FALSE, /* hosts_randomize */
1711 FALSE, /* gethostbyname */
1712 TRUE, /* qualify_single */
1713 FALSE /* search_parents */
1714 };
1715
1716 /* If verification yielded a remote transport, we want to use that
1717 transport's options, so as to mimic what would happen if we were really
1718 sending a message to this address. */
1719
1720 if (addr->transport != NULL && !addr->transport->info->local)
1721 {
1722 (void)(addr->transport->setup)(addr->transport, addr, &tf, 0, 0, NULL);
1723
1724 /* If the transport has hosts and the router does not, or if the
1725 transport is configured to override the router's hosts, we must build a
1726 host list of the transport's hosts, and find the IP addresses */
1727
1728 if (tf.hosts != NULL && (host_list == NULL || tf.hosts_override))
1729 {
1730 uschar *s;
1731 uschar *save_deliver_domain = deliver_domain;
1732 uschar *save_deliver_localpart = deliver_localpart;
1733
1734 host_list = NULL; /* Ignore the router's hosts */
1735
1736 deliver_domain = addr->domain;
1737 deliver_localpart = addr->local_part;
1738 s = expand_string(tf.hosts);
1739 deliver_domain = save_deliver_domain;
1740 deliver_localpart = save_deliver_localpart;
1741
1742 if (s == NULL)
1743 {
1744 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand list of hosts "
1745 "\"%s\" in %s transport for callout: %s", tf.hosts,
1746 addr->transport->name, expand_string_message);
1747 }
1748 else
1749 {
1750 int flags;
1751 uschar *canonical_name;
1752 host_item *host, *nexthost;
1753 host_build_hostlist(&host_list, s, tf.hosts_randomize);
1754
1755 /* Just ignore failures to find a host address. If we don't manage
1756 to find any addresses, the callout will defer. Note that more than
1757 one address may be found for a single host, which will result in
1758 additional host items being inserted into the chain. Hence we must
1759 save the next host first. */
1760
1761 flags = HOST_FIND_BY_A;
1762 if (tf.qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
1763 if (tf.search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
1764
1765 for (host = host_list; host != NULL; host = nexthost)
1766 {
1767 nexthost = host->next;
1768 if (tf.gethostbyname ||
1769 string_is_ip_address(host->name, NULL) != 0)
1770 (void)host_find_byname(host, NULL, flags, &canonical_name, TRUE);
1771 else
1772 {
1773 uschar * d_request = NULL, * d_require = NULL;
1774 if (Ustrcmp(addr->transport->driver_name, "smtp") == 0)
1775 {
1776 smtp_transport_options_block * ob =
1777 (smtp_transport_options_block *)
1778 addr->transport->options_block;
1779 d_request = ob->dnssec_request_domains;
1780 d_require = ob->dnssec_require_domains;
1781 }
1782
1783 (void)host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
1784 d_request, d_require, &canonical_name, NULL);
1785 }
1786 }
1787 }
1788 }
1789 }
1790
1791 /* Can only do a callout if we have at least one host! If the callout
1792 fails, it will have set ${sender,recipient}_verify_failure. */
1793
1794 if (host_list != NULL)
1795 {
1796 HDEBUG(D_verify) debug_printf("Attempting full verification using callout\n");
1797 if (host_checking && !host_checking_callout)
1798 {
1799 HDEBUG(D_verify)
1800 debug_printf("... callout omitted by default when host testing\n"
1801 "(Use -bhc if you want the callouts to happen.)\n");
1802 }
1803 else
1804 {
1805 #ifdef SUPPORT_TLS
1806 deliver_set_expansions(addr);
1807 #endif
1808 rc = do_callout(addr, host_list, &tf, callout, callout_overall,
1809 callout_connect, options, se_mailfrom, pm_mailfrom);
1810 }
1811 }
1812 else
1813 {
1814 HDEBUG(D_verify) debug_printf("Cannot do callout: neither router nor "
1815 "transport provided a host list\n");
1816 }
1817 }
1818 }
1819
1820 /* Otherwise, any failure is a routing failure */
1821
1822 else *failure_ptr = US"route";
1823
1824 /* A router may return REROUTED if it has set up a child address as a result
1825 of a change of domain name (typically from widening). In this case we always
1826 want to continue to verify the new child. */
1827
1828 if (rc == REROUTED) continue;
1829
1830 /* Handle hard failures */
1831
1832 if (rc == FAIL)
1833 {
1834 allok = FALSE;
1835 if (f != NULL)
1836 {
1837 address_item *p = addr->parent;
1838
1839 respond_printf(f, "%s%s %s", ko_prefix,
1840 full_info? addr->address : address,
1841 address_test_mode? "is undeliverable" : "failed to verify");
1842 if (!expn && admin_user)
1843 {
1844 if (addr->basic_errno > 0)
1845 respond_printf(f, ": %s", strerror(addr->basic_errno));
1846 if (addr->message != NULL)
1847 respond_printf(f, ": %s", addr->message);
1848 }
1849
1850 /* Show parents iff doing full info */
1851
1852 if (full_info) while (p != NULL)
1853 {
1854 respond_printf(f, "%s\n <-- %s", cr, p->address);
1855 p = p->parent;
1856 }
1857 respond_printf(f, "%s\n", cr);
1858 }
1859 cancel_cutthrough_connection("routing hard fail");
1860
1861 if (!full_info)
1862 {
1863 yield = copy_error(vaddr, addr, FAIL);
1864 goto out;
1865 }
1866 else yield = FAIL;
1867 }
1868
1869 /* Soft failure */
1870
1871 else if (rc == DEFER)
1872 {
1873 allok = FALSE;
1874 if (f != NULL)
1875 {
1876 address_item *p = addr->parent;
1877 respond_printf(f, "%s%s cannot be resolved at this time", ko_prefix,
1878 full_info? addr->address : address);
1879 if (!expn && admin_user)
1880 {
1881 if (addr->basic_errno > 0)
1882 respond_printf(f, ": %s", strerror(addr->basic_errno));
1883 if (addr->message != NULL)
1884 respond_printf(f, ": %s", addr->message);
1885 else if (addr->basic_errno <= 0)
1886 respond_printf(f, ": unknown error");
1887 }
1888
1889 /* Show parents iff doing full info */
1890
1891 if (full_info) while (p != NULL)
1892 {
1893 respond_printf(f, "%s\n <-- %s", cr, p->address);
1894 p = p->parent;
1895 }
1896 respond_printf(f, "%s\n", cr);
1897 }
1898 cancel_cutthrough_connection("routing soft fail");
1899
1900 if (!full_info)
1901 {
1902 yield = copy_error(vaddr, addr, DEFER);
1903 goto out;
1904 }
1905 else if (yield == OK) yield = DEFER;
1906 }
1907
1908 /* If we are handling EXPN, we do not want to continue to route beyond
1909 the top level (whose address is in "address"). */
1910
1911 else if (expn)
1912 {
1913 uschar *ok_prefix = US"250-";
1914 if (addr_new == NULL)
1915 {
1916 if (addr_local == NULL && addr_remote == NULL)
1917 respond_printf(f, "250 mail to <%s> is discarded\r\n", address);
1918 else
1919 respond_printf(f, "250 <%s>\r\n", address);
1920 }
1921 else while (addr_new != NULL)
1922 {
1923 address_item *addr2 = addr_new;
1924 addr_new = addr2->next;
1925 if (addr_new == NULL) ok_prefix = US"250 ";
1926 respond_printf(f, "%s<%s>\r\n", ok_prefix, addr2->address);
1927 }
1928 yield = OK;
1929 goto out;
1930 }
1931
1932 /* Successful routing other than EXPN. */
1933
1934 else
1935 {
1936 /* Handle successful routing when short info wanted. Otherwise continue for
1937 other (generated) addresses. Short info is the operational case. Full info
1938 can be requested only when debug_selector != 0 and a file is supplied.
1939
1940 There is a conflict between the use of aliasing as an alternate email
1941 address, and as a sort of mailing list. If an alias turns the incoming
1942 address into just one address (e.g. J.Caesar->jc44) you may well want to
1943 carry on verifying the generated address to ensure it is valid when
1944 checking incoming mail. If aliasing generates multiple addresses, you
1945 probably don't want to do this. Exim therefore treats the generation of
1946 just a single new address as a special case, and continues on to verify the
1947 generated address. */
1948
1949 if (!full_info && /* Stop if short info wanted AND */
1950 (((addr_new == NULL || /* No new address OR */
1951 addr_new->next != NULL || /* More than one new address OR */
1952 testflag(addr_new, af_pfr))) /* New address is pfr */
1953 || /* OR */
1954 (addr_new != NULL && /* At least one new address AND */
1955 success_on_redirect))) /* success_on_redirect is set */
1956 {
1957 if (f != NULL) fprintf(f, "%s %s\n", address,
1958 address_test_mode? "is deliverable" : "verified");
1959
1960 /* If we have carried on to verify a child address, we want the value
1961 of $address_data to be that of the child */
1962
1963 vaddr->p.address_data = addr->p.address_data;
1964 yield = OK;
1965 goto out;
1966 }
1967 }
1968 } /* Loop for generated addresses */
1969
1970 /* Display the full results of the successful routing, including any generated
1971 addresses. Control gets here only when full_info is set, which requires f not
1972 to be NULL, and this occurs only when a top-level verify is called with the
1973 debugging switch on.
1974
1975 If there are no local and no remote addresses, and there were no pipes, files,
1976 or autoreplies, and there were no errors or deferments, the message is to be
1977 discarded, usually because of the use of :blackhole: in an alias file. */
1978
1979 if (allok && addr_local == NULL && addr_remote == NULL)
1980 {
1981 fprintf(f, "mail to %s is discarded\n", address);
1982 goto out;
1983 }
1984
1985 for (addr_list = addr_local, i = 0; i < 2; addr_list = addr_remote, i++)
1986 {
1987 while (addr_list != NULL)
1988 {
1989 address_item *addr = addr_list;
1990 address_item *p = addr->parent;
1991 addr_list = addr->next;
1992
1993 fprintf(f, "%s", CS addr->address);
1994 #ifdef EXPERIMENTAL_SRS
1995 if(addr->p.srs_sender)
1996 fprintf(f, " [srs = %s]", addr->p.srs_sender);
1997 #endif
1998
1999 /* If the address is a duplicate, show something about it. */
2000
2001 if (!testflag(addr, af_pfr))
2002 {
2003 tree_node *tnode;
2004 if ((tnode = tree_search(tree_duplicates, addr->unique)) != NULL)
2005 fprintf(f, " [duplicate, would not be delivered]");
2006 else tree_add_duplicate(addr->unique, addr);
2007 }
2008
2009 /* Now show its parents */
2010
2011 while (p != NULL)
2012 {
2013 fprintf(f, "\n <-- %s", p->address);
2014 p = p->parent;
2015 }
2016 fprintf(f, "\n ");
2017
2018 /* Show router, and transport */
2019
2020 fprintf(f, "router = %s, ", addr->router->name);
2021 fprintf(f, "transport = %s\n", (addr->transport == NULL)? US"unset" :
2022 addr->transport->name);
2023
2024 /* Show any hosts that are set up by a router unless the transport
2025 is going to override them; fiddle a bit to get a nice format. */
2026
2027 if (addr->host_list != NULL && addr->transport != NULL &&
2028 !addr->transport->overrides_hosts)
2029 {
2030 host_item *h;
2031 int maxlen = 0;
2032 int maxaddlen = 0;
2033 for (h = addr->host_list; h != NULL; h = h->next)
2034 {
2035 int len = Ustrlen(h->name);
2036 if (len > maxlen) maxlen = len;
2037 len = (h->address != NULL)? Ustrlen(h->address) : 7;
2038 if (len > maxaddlen) maxaddlen = len;
2039 }
2040 for (h = addr->host_list; h != NULL; h = h->next)
2041 {
2042 int len = Ustrlen(h->name);
2043 fprintf(f, " host %s ", h->name);
2044 while (len++ < maxlen) fprintf(f, " ");
2045 if (h->address != NULL)
2046 {
2047 fprintf(f, "[%s] ", h->address);
2048 len = Ustrlen(h->address);
2049 }
2050 else if (!addr->transport->info->local) /* Omit [unknown] for local */
2051 {
2052 fprintf(f, "[unknown] ");
2053 len = 7;
2054 }
2055 else len = -3;
2056 while (len++ < maxaddlen) fprintf(f," ");
2057 if (h->mx >= 0) fprintf(f, "MX=%d", h->mx);
2058 if (h->port != PORT_NONE) fprintf(f, " port=%d", h->port);
2059 if (h->status == hstatus_unusable) fprintf(f, " ** unusable **");
2060 fprintf(f, "\n");
2061 }
2062 }
2063 }
2064 }
2065
2066 /* Yield will be DEFER or FAIL if any one address has, only for full_info (which is
2067 the -bv or -bt case). */
2068
2069 out:
2070 tls_modify_variables(&tls_in);
2071
2072 return yield;
2073 }
2074
2075
2076
2077
2078 /*************************************************
2079 * Check headers for syntax errors *
2080 *************************************************/
2081
2082 /* This function checks those header lines that contain addresses, and verifies
2083 that all the addresses therein are syntactially correct.
2084
2085 Arguments:
2086 msgptr where to put an error message
2087
2088 Returns: OK
2089 FAIL
2090 */
2091
2092 int
2093 verify_check_headers(uschar **msgptr)
2094 {
2095 header_line *h;
2096 uschar *colon, *s;
2097 int yield = OK;
2098
2099 for (h = header_list; h != NULL && yield == OK; h = h->next)
2100 {
2101 if (h->type != htype_from &&
2102 h->type != htype_reply_to &&
2103 h->type != htype_sender &&
2104 h->type != htype_to &&
2105 h->type != htype_cc &&
2106 h->type != htype_bcc)
2107 continue;
2108
2109 colon = Ustrchr(h->text, ':');
2110 s = colon + 1;
2111 while (isspace(*s)) s++;
2112
2113 /* Loop for multiple addresses in the header, enabling group syntax. Note
2114 that we have to reset this after the header has been scanned. */
2115
2116 parse_allow_group = TRUE;
2117
2118 while (*s != 0)
2119 {
2120 uschar *ss = parse_find_address_end(s, FALSE);
2121 uschar *recipient, *errmess;
2122 int terminator = *ss;
2123 int start, end, domain;
2124
2125 /* Temporarily terminate the string at this point, and extract the
2126 operative address within, allowing group syntax. */
2127
2128 *ss = 0;
2129 recipient = parse_extract_address(s,&errmess,&start,&end,&domain,FALSE);
2130 *ss = terminator;
2131
2132 /* Permit an unqualified address only if the message is local, or if the
2133 sending host is configured to be permitted to send them. */
2134
2135 if (recipient != NULL && domain == 0)
2136 {
2137 if (h->type == htype_from || h->type == htype_sender)
2138 {
2139 if (!allow_unqualified_sender) recipient = NULL;
2140 }
2141 else
2142 {
2143 if (!allow_unqualified_recipient) recipient = NULL;
2144 }
2145 if (recipient == NULL) errmess = US"unqualified address not permitted";
2146 }
2147
2148 /* It's an error if no address could be extracted, except for the special
2149 case of an empty address. */
2150
2151 if (recipient == NULL && Ustrcmp(errmess, "empty address") != 0)
2152 {
2153 uschar *verb = US"is";
2154 uschar *t = ss;
2155 uschar *tt = colon;
2156 int len;
2157
2158 /* Arrange not to include any white space at the end in the
2159 error message or the header name. */
2160
2161 while (t > s && isspace(t[-1])) t--;
2162 while (tt > h->text && isspace(tt[-1])) tt--;
2163
2164 /* Add the address that failed to the error message, since in a
2165 header with very many addresses it is sometimes hard to spot
2166 which one is at fault. However, limit the amount of address to
2167 quote - cases have been seen where, for example, a missing double
2168 quote in a humungous To: header creates an "address" that is longer
2169 than string_sprintf can handle. */
2170
2171 len = t - s;
2172 if (len > 1024)
2173 {
2174 len = 1024;
2175 verb = US"begins";
2176 }
2177
2178 *msgptr = string_printing(
2179 string_sprintf("%s: failing address in \"%.*s:\" header %s: %.*s",
2180 errmess, tt - h->text, h->text, verb, len, s));
2181
2182 yield = FAIL;
2183 break; /* Out of address loop */
2184 }
2185
2186 /* Advance to the next address */
2187
2188 s = ss + (terminator? 1:0);
2189 while (isspace(*s)) s++;
2190 } /* Next address */
2191
2192 parse_allow_group = FALSE;
2193 parse_found_group = FALSE;
2194 } /* Next header unless yield has been set FALSE */
2195
2196 return yield;
2197 }
2198
2199
2200 /*************************************************
2201 * Check header names for 8-bit characters *
2202 *************************************************/
2203
2204 /* This function checks for invalid charcters in header names. See
2205 RFC 5322, 2.2. and RFC 6532, 3.
2206
2207 Arguments:
2208 msgptr where to put an error message
2209
2210 Returns: OK
2211 FAIL
2212 */
2213
2214 int
2215 verify_check_header_names_ascii(uschar **msgptr)
2216 {
2217 header_line *h;
2218 uschar *colon, *s;
2219
2220 for (h = header_list; h != NULL; h = h->next)
2221 {
2222 colon = Ustrchr(h->text, ':');
2223 for(s = h->text; s < colon; s++)
2224 {
2225 if ((*s < 33) || (*s > 126))
2226 {
2227 *msgptr = string_sprintf("Invalid character in header \"%.*s\" found",
2228 colon - h->text, h->text);
2229 return FAIL;
2230 }
2231 }
2232 }
2233 return OK;
2234 }
2235
2236 /*************************************************
2237 * Check for blind recipients *
2238 *************************************************/
2239
2240 /* This function checks that every (envelope) recipient is mentioned in either
2241 the To: or Cc: header lines, thus detecting blind carbon copies.
2242
2243 There are two ways of scanning that could be used: either scan the header lines
2244 and tick off the recipients, or scan the recipients and check the header lines.
2245 The original proposed patch did the former, but I have chosen to do the latter,
2246 because (a) it requires no memory and (b) will use fewer resources when there
2247 are many addresses in To: and/or Cc: and only one or two envelope recipients.
2248
2249 Arguments: none
2250 Returns: OK if there are no blind recipients
2251 FAIL if there is at least one blind recipient
2252 */
2253
2254 int
2255 verify_check_notblind(void)
2256 {
2257 int i;
2258 for (i = 0; i < recipients_count; i++)
2259 {
2260 header_line *h;
2261 BOOL found = FALSE;
2262 uschar *address = recipients_list[i].address;
2263
2264 for (h = header_list; !found && h != NULL; h = h->next)
2265 {
2266 uschar *colon, *s;
2267
2268 if (h->type != htype_to && h->type != htype_cc) continue;
2269
2270 colon = Ustrchr(h->text, ':');
2271 s = colon + 1;
2272 while (isspace(*s)) s++;
2273
2274 /* Loop for multiple addresses in the header, enabling group syntax. Note
2275 that we have to reset this after the header has been scanned. */
2276
2277 parse_allow_group = TRUE;
2278
2279 while (*s != 0)
2280 {
2281 uschar *ss = parse_find_address_end(s, FALSE);
2282 uschar *recipient,*errmess;
2283 int terminator = *ss;
2284 int start, end, domain;
2285
2286 /* Temporarily terminate the string at this point, and extract the
2287 operative address within, allowing group syntax. */
2288
2289 *ss = 0;
2290 recipient = parse_extract_address(s,&errmess,&start,&end,&domain,FALSE);
2291 *ss = terminator;
2292
2293 /* If we found a valid recipient that has a domain, compare it with the
2294 envelope recipient. Local parts are compared case-sensitively, domains
2295 case-insensitively. By comparing from the start with length "domain", we
2296 include the "@" at the end, which ensures that we are comparing the whole
2297 local part of each address. */
2298
2299 if (recipient != NULL && domain != 0)
2300 {
2301 found = Ustrncmp(recipient, address, domain) == 0 &&
2302 strcmpic(recipient + domain, address + domain) == 0;
2303 if (found) break;
2304 }
2305
2306 /* Advance to the next address */
2307
2308 s = ss + (terminator? 1:0);
2309 while (isspace(*s)) s++;
2310 } /* Next address */
2311
2312 parse_allow_group = FALSE;
2313 parse_found_group = FALSE;
2314 } /* Next header (if found is false) */
2315
2316 if (!found) return FAIL;
2317 } /* Next recipient */
2318
2319 return OK;
2320 }
2321
2322
2323
2324 /*************************************************
2325 * Find if verified sender *
2326 *************************************************/
2327
2328 /* Usually, just a single address is verified as the sender of the message.
2329 However, Exim can be made to verify other addresses as well (often related in
2330 some way), and this is useful in some environments. There may therefore be a
2331 chain of such addresses that have previously been tested. This function finds
2332 whether a given address is on the chain.
2333
2334 Arguments: the address to be verified
2335 Returns: pointer to an address item, or NULL
2336 */
2337
2338 address_item *
2339 verify_checked_sender(uschar *sender)
2340 {
2341 address_item *addr;
2342 for (addr = sender_verified_list; addr != NULL; addr = addr->next)
2343 if (Ustrcmp(sender, addr->address) == 0) break;
2344 return addr;
2345 }
2346
2347
2348
2349
2350
2351 /*************************************************
2352 * Get valid header address *
2353 *************************************************/
2354
2355 /* Scan the originator headers of the message, looking for an address that
2356 verifies successfully. RFC 822 says:
2357
2358 o The "Sender" field mailbox should be sent notices of
2359 any problems in transport or delivery of the original
2360 messages. If there is no "Sender" field, then the
2361 "From" field mailbox should be used.
2362
2363 o If the "Reply-To" field exists, then the reply should
2364 go to the addresses indicated in that field and not to
2365 the address(es) indicated in the "From" field.
2366
2367 So we check a Sender field if there is one, else a Reply_to field, else a From
2368 field. As some strange messages may have more than one of these fields,
2369 especially if they are resent- fields, check all of them if there is more than
2370 one.
2371
2372 Arguments:
2373 user_msgptr points to where to put a user error message
2374 log_msgptr points to where to put a log error message
2375 callout timeout for callout check (passed to verify_address())
2376 callout_overall overall callout timeout (ditto)
2377 callout_connect connect callout timeout (ditto)
2378 se_mailfrom mailfrom for verify; NULL => ""
2379 pm_mailfrom sender for pm callout check (passed to verify_address())
2380 options callout options (passed to verify_address())
2381 verrno where to put the address basic_errno
2382
2383 If log_msgptr is set to something without setting user_msgptr, the caller
2384 normally uses log_msgptr for both things.
2385
2386 Returns: result of the verification attempt: OK, FAIL, or DEFER;
2387 FAIL is given if no appropriate headers are found
2388 */
2389
2390 int
2391 verify_check_header_address(uschar **user_msgptr, uschar **log_msgptr,
2392 int callout, int callout_overall, int callout_connect, uschar *se_mailfrom,
2393 uschar *pm_mailfrom, int options, int *verrno)
2394 {
2395 static int header_types[] = { htype_sender, htype_reply_to, htype_from };
2396 BOOL done = FALSE;
2397 int yield = FAIL;
2398 int i;
2399
2400 for (i = 0; i < 3 && !done; i++)
2401 {
2402 header_line *h;
2403 for (h = header_list; h != NULL && !done; h = h->next)
2404 {
2405 int terminator, new_ok;
2406 uschar *s, *ss, *endname;
2407
2408 if (h->type != header_types[i]) continue;
2409 s = endname = Ustrchr(h->text, ':') + 1;
2410
2411 /* Scan the addresses in the header, enabling group syntax. Note that we
2412 have to reset this after the header has been scanned. */
2413
2414 parse_allow_group = TRUE;
2415
2416 while (*s != 0)
2417 {
2418 address_item *vaddr;
2419
2420 while (isspace(*s) || *s == ',') s++;
2421 if (*s == 0) break; /* End of header */
2422
2423 ss = parse_find_address_end(s, FALSE);
2424
2425 /* The terminator is a comma or end of header, but there may be white
2426 space preceding it (including newline for the last address). Move back
2427 past any white space so we can check against any cached envelope sender
2428 address verifications. */
2429
2430 while (isspace(ss[-1])) ss--;
2431 terminator = *ss;
2432 *ss = 0;
2433
2434 HDEBUG(D_verify) debug_printf("verifying %.*s header address %s\n",
2435 (int)(endname - h->text), h->text, s);
2436
2437 /* See if we have already verified this address as an envelope sender,
2438 and if so, use the previous answer. */
2439
2440 vaddr = verify_checked_sender(s);
2441
2442 if (vaddr != NULL && /* Previously checked */
2443 (callout <= 0 || /* No callout needed; OR */
2444 vaddr->special_action > 256)) /* Callout was done */
2445 {
2446 new_ok = vaddr->special_action & 255;
2447 HDEBUG(D_verify) debug_printf("previously checked as envelope sender\n");
2448 *ss = terminator; /* Restore shortened string */
2449 }
2450
2451 /* Otherwise we run the verification now. We must restore the shortened
2452 string before running the verification, so the headers are correct, in
2453 case there is any rewriting. */
2454
2455 else
2456 {
2457 int start, end, domain;
2458 uschar *address = parse_extract_address(s, log_msgptr, &start, &end,
2459 &domain, FALSE);
2460
2461 *ss = terminator;
2462
2463 /* If we found an empty address, just carry on with the next one, but
2464 kill the message. */
2465
2466 if (address == NULL && Ustrcmp(*log_msgptr, "empty address") == 0)
2467 {
2468 *log_msgptr = NULL;
2469 s = ss;
2470 continue;
2471 }
2472
2473 /* If verification failed because of a syntax error, fail this
2474 function, and ensure that the failing address gets added to the error
2475 message. */
2476
2477 if (address == NULL)
2478 {
2479 new_ok = FAIL;
2480 while (ss > s && isspace(ss[-1])) ss--;
2481 *log_msgptr = string_sprintf("syntax error in '%.*s' header when "
2482 "scanning for sender: %s in \"%.*s\"",
2483 endname - h->text, h->text, *log_msgptr, ss - s, s);
2484 yield = FAIL;
2485 done = TRUE;
2486 break;
2487 }
2488
2489 /* Else go ahead with the sender verification. But it isn't *the*
2490 sender of the message, so set vopt_fake_sender to stop sender_address
2491 being replaced after rewriting or qualification. */
2492
2493 else
2494 {
2495 vaddr = deliver_make_addr(address, FALSE);
2496 new_ok = verify_address(vaddr, NULL, options | vopt_fake_sender,
2497 callout, callout_overall, callout_connect, se_mailfrom,
2498 pm_mailfrom, NULL);
2499 }
2500 }
2501
2502 /* We now have the result, either newly found, or cached. If we are
2503 giving out error details, set a specific user error. This means that the
2504 last of these will be returned to the user if all three fail. We do not
2505 set a log message - the generic one below will be used. */
2506
2507 if (new_ok != OK)
2508 {
2509 *verrno = vaddr->basic_errno;
2510 if (smtp_return_error_details)
2511 {
2512 *user_msgptr = string_sprintf("Rejected after DATA: "
2513 "could not verify \"%.*s\" header address\n%s: %s",
2514 endname - h->text, h->text, vaddr->address, vaddr->message);
2515 }
2516 }
2517
2518 /* Success or defer */
2519
2520 if (new_ok == OK)
2521 {
2522 yield = OK;
2523 done = TRUE;
2524 break;
2525 }
2526
2527 if (new_ok == DEFER) yield = DEFER;
2528
2529 /* Move on to any more addresses in the header */
2530
2531 s = ss;
2532 } /* Next address */
2533
2534 parse_allow_group = FALSE;
2535 parse_found_group = FALSE;
2536 } /* Next header, unless done */
2537 } /* Next header type unless done */
2538
2539 if (yield == FAIL && *log_msgptr == NULL)
2540 *log_msgptr = US"there is no valid sender in any header line";
2541
2542 if (yield == DEFER && *log_msgptr == NULL)
2543 *log_msgptr = US"all attempts to verify a sender in a header line deferred";
2544
2545 return yield;
2546 }
2547
2548
2549
2550
2551 /*************************************************
2552 * Get RFC 1413 identification *
2553 *************************************************/
2554
2555 /* Attempt to get an id from the sending machine via the RFC 1413 protocol. If
2556 the timeout is set to zero, then the query is not done. There may also be lists
2557 of hosts and nets which are exempt. To guard against malefactors sending
2558 non-printing characters which could, for example, disrupt a message's headers,
2559 make sure the string consists of printing characters only.
2560
2561 Argument:
2562 port the port to connect to; usually this is IDENT_PORT (113), but when
2563 running in the test harness with -bh a different value is used.
2564
2565 Returns: nothing
2566
2567 Side effect: any received ident value is put in sender_ident (NULL otherwise)
2568 */
2569
2570 void
2571 verify_get_ident(int port)
2572 {
2573 int sock, host_af, qlen;
2574 int received_sender_port, received_interface_port, n;
2575 uschar *p;
2576 uschar buffer[2048];
2577
2578 /* Default is no ident. Check whether we want to do an ident check for this
2579 host. */
2580
2581 sender_ident = NULL;
2582 if (rfc1413_query_timeout <= 0 || verify_check_host(&rfc1413_hosts) != OK)
2583 return;
2584
2585 DEBUG(D_ident) debug_printf("doing ident callback\n");
2586
2587 /* Set up a connection to the ident port of the remote host. Bind the local end
2588 to the incoming interface address. If the sender host address is an IPv6
2589 address, the incoming interface address will also be IPv6. */
2590
2591 host_af = (Ustrchr(sender_host_address, ':') == NULL)? AF_INET : AF_INET6;
2592 sock = ip_socket(SOCK_STREAM, host_af);
2593 if (sock < 0) return;
2594
2595 if (ip_bind(sock, host_af, interface_address, 0) < 0)
2596 {
2597 DEBUG(D_ident) debug_printf("bind socket for ident failed: %s\n",
2598 strerror(errno));
2599 goto END_OFF;
2600 }
2601
2602 if (ip_connect(sock, host_af, sender_host_address, port, rfc1413_query_timeout)
2603 < 0)
2604 {
2605 if (errno == ETIMEDOUT && (log_extra_selector & LX_ident_timeout) != 0)
2606 {
2607 log_write(0, LOG_MAIN, "ident connection to %s timed out",
2608 sender_host_address);
2609 }
2610 else
2611 {
2612 DEBUG(D_ident) debug_printf("ident connection to %s failed: %s\n",
2613 sender_host_address, strerror(errno));
2614 }
2615 goto END_OFF;
2616 }
2617
2618 /* Construct and send the query. */
2619
2620 sprintf(CS buffer, "%d , %d\r\n", sender_host_port, interface_port);
2621 qlen = Ustrlen(buffer);
2622 if (send(sock, buffer, qlen, 0) < 0)
2623 {
2624 DEBUG(D_ident) debug_printf("ident send failed: %s\n", strerror(errno));
2625 goto END_OFF;
2626 }
2627
2628 /* Read a response line. We put it into the rest of the buffer, using several
2629 recv() calls if necessary. */
2630
2631 p = buffer + qlen;
2632
2633 for (;;)
2634 {
2635 uschar *pp;
2636 int count;
2637 int size = sizeof(buffer) - (p - buffer);
2638
2639 if (size <= 0) goto END_OFF; /* Buffer filled without seeing \n. */
2640 count = ip_recv(sock, p, size, rfc1413_query_timeout);
2641 if (count <= 0) goto END_OFF; /* Read error or EOF */
2642
2643 /* Scan what we just read, to see if we have reached the terminating \r\n. Be
2644 generous, and accept a plain \n terminator as well. The only illegal
2645 character is 0. */
2646
2647 for (pp = p; pp < p + count; pp++)
2648 {
2649 if (*pp == 0) goto END_OFF; /* Zero octet not allowed */
2650 if (*pp == '\n')
2651 {
2652 if (pp[-1] == '\r') pp--;
2653 *pp = 0;
2654 goto GOT_DATA; /* Break out of both loops */
2655 }
2656 }
2657
2658 /* Reached the end of the data without finding \n. Let the loop continue to
2659 read some more, if there is room. */
2660
2661 p = pp;
2662 }
2663
2664 GOT_DATA:
2665
2666 /* We have received a line of data. Check it carefully. It must start with the
2667 same two port numbers that we sent, followed by data as defined by the RFC. For
2668 example,
2669
2670 12345 , 25 : USERID : UNIX :root
2671
2672 However, the amount of white space may be different to what we sent. In the
2673 "osname" field there may be several sub-fields, comma separated. The data we
2674 actually want to save follows the third colon. Some systems put leading spaces
2675 in it - we discard those. */
2676
2677 if (sscanf(CS buffer + qlen, "%d , %d%n", &received_sender_port,
2678 &received_interface_port, &n) != 2 ||
2679 received_sender_port != sender_host_port ||
2680 received_interface_port != interface_port)
2681 goto END_OFF;
2682
2683 p = buffer + qlen + n;
2684 while(isspace(*p)) p++;
2685 if (*p++ != ':') goto END_OFF;
2686 while(isspace(*p)) p++;
2687 if (Ustrncmp(p, "USERID", 6) != 0) goto END_OFF;
2688 p += 6;
2689 while(isspace(*p)) p++;
2690 if (*p++ != ':') goto END_OFF;
2691 while (*p != 0 && *p != ':') p++;
2692 if (*p++ == 0) goto END_OFF;
2693 while(isspace(*p)) p++;
2694 if (*p == 0) goto END_OFF;
2695
2696 /* The rest of the line is the data we want. We turn it into printing
2697 characters when we save it, so that it cannot mess up the format of any logging
2698 or Received: lines into which it gets inserted. We keep a maximum of 127
2699 characters. */
2700
2701 sender_ident = string_printing(string_copyn(p, 127));
2702 DEBUG(D_ident) debug_printf("sender_ident = %s\n", sender_ident);
2703
2704 END_OFF:
2705 (void)close(sock);
2706 return;
2707 }
2708
2709
2710
2711
2712 /*************************************************
2713 * Match host to a single host-list item *
2714 *************************************************/
2715
2716 /* This function compares a host (name or address) against a single item
2717 from a host list. The host name gets looked up if it is needed and is not
2718 already known. The function is called from verify_check_this_host() via
2719 match_check_list(), which is why most of its arguments are in a single block.
2720
2721 Arguments:
2722 arg the argument block (see below)
2723 ss the host-list item
2724 valueptr where to pass back looked up data, or NULL
2725 error for error message when returning ERROR
2726
2727 The block contains:
2728 host_name (a) the host name, or
2729 (b) NULL, implying use sender_host_name and
2730 sender_host_aliases, looking them up if required, or
2731 (c) the empty string, meaning that only IP address matches
2732 are permitted
2733 host_address the host address
2734 host_ipv4 the IPv4 address taken from an IPv6 one
2735
2736 Returns: OK matched
2737 FAIL did not match
2738 DEFER lookup deferred
2739 ERROR (a) failed to find the host name or IP address, or
2740 (b) unknown lookup type specified, or
2741 (c) host name encountered when only IP addresses are
2742 being matched
2743 */
2744
2745 int
2746 check_host(void *arg, uschar *ss, uschar **valueptr, uschar **error)
2747 {
2748 check_host_block *cb = (check_host_block *)arg;
2749 int mlen = -1;
2750 int maskoffset;
2751 BOOL iplookup = FALSE;
2752 BOOL isquery = FALSE;
2753 BOOL isiponly = cb->host_name != NULL && cb->host_name[0] == 0;
2754 uschar *t;
2755 uschar *semicolon;
2756 uschar **aliases;
2757
2758 /* Optimize for the special case when the pattern is "*". */
2759
2760 if (*ss == '*' && ss[1] == 0) return OK;
2761
2762 /* If the pattern is empty, it matches only in the case when there is no host -
2763 this can occur in ACL checking for SMTP input using the -bs option. In this
2764 situation, the host address is the empty string. */
2765
2766 if (cb->host_address[0] == 0) return (*ss == 0)? OK : FAIL;
2767 if (*ss == 0) return FAIL;
2768
2769 /* If the pattern is precisely "@" then match against the primary host name,
2770 provided that host name matching is permitted; if it's "@[]" match against the
2771 local host's IP addresses. */
2772
2773 if (*ss == '@')
2774 {
2775 if (ss[1] == 0)
2776 {
2777 if (isiponly) return ERROR;
2778 ss = primary_hostname;
2779 }
2780 else if (Ustrcmp(ss, "@[]") == 0)
2781 {
2782 ip_address_item *ip;
2783 for (ip = host_find_interfaces(); ip != NULL; ip = ip->next)
2784 if (Ustrcmp(ip->address, cb->host_address) == 0) return OK;
2785 return FAIL;
2786 }
2787 }
2788
2789 /* If the pattern is an IP address, optionally followed by a bitmask count, do
2790 a (possibly masked) comparision with the current IP address. */
2791
2792 if (string_is_ip_address(ss, &maskoffset) != 0)
2793 return (host_is_in_net(cb->host_address, ss, maskoffset)? OK : FAIL);
2794
2795 /* The pattern is not an IP address. A common error that people make is to omit
2796 one component of an IPv4 address, either by accident, or believing that, for
2797 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,
2798 which it isn't. (Those applications that do accept 1.2.3 as an IP address
2799 interpret it as 1.2.0.3 because the final component becomes 16-bit - this is an
2800 ancient specification.) To aid in debugging these cases, we give a specific
2801 error if the pattern contains only digits and dots or contains a slash preceded
2802 only by digits and dots (a slash at the start indicates a file name and of
2803 course slashes may be present in lookups, but not preceded only by digits and
2804 dots). */
2805
2806 for (t = ss; isdigit(*t) || *t == '.'; t++);
2807 if (*t == 0 || (*t == '/' && t != ss))
2808 {
2809 *error = US"malformed IPv4 address or address mask";
2810 return ERROR;
2811 }
2812
2813 /* See if there is a semicolon in the pattern */
2814
2815 semicolon = Ustrchr(ss, ';');
2816
2817 /* If we are doing an IP address only match, then all lookups must be IP
2818 address lookups, even if there is no "net-". */
2819
2820 if (isiponly)
2821 {
2822 iplookup = semicolon != NULL;
2823 }
2824
2825 /* Otherwise, if the item is of the form net[n]-lookup;<file|query> then it is
2826 a lookup on a masked IP network, in textual form. We obey this code even if we
2827 have already set iplookup, so as to skip over the "net-" prefix and to set the
2828 mask length. The net- stuff really only applies to single-key lookups where the
2829 key is implicit. For query-style lookups the key is specified in the query.
2830 From release 4.30, the use of net- for query style is no longer needed, but we
2831 retain it for backward compatibility. */
2832
2833 if (Ustrncmp(ss, "net", 3) == 0 && semicolon != NULL)
2834 {
2835 mlen = 0;
2836 for (t = ss + 3; isdigit(*t); t++) mlen = mlen * 10 + *t - '0';
2837 if (mlen == 0 && t == ss+3) mlen = -1; /* No mask supplied */
2838 iplookup = (*t++ == '-');
2839 }
2840 else t = ss;
2841
2842 /* Do the IP address lookup if that is indeed what we have */
2843
2844 if (iplookup)
2845 {
2846 int insize;
2847 int search_type;
2848 int incoming[4];
2849 void *handle;
2850 uschar *filename, *key, *result;
2851 uschar buffer[64];
2852
2853 /* Find the search type */
2854
2855 search_type = search_findtype(t, semicolon - t);
2856
2857 if (search_type < 0) log_write(0, LOG_MAIN|LOG_PANIC_DIE, "%s",
2858 search_error_message);
2859
2860 /* Adjust parameters for the type of lookup. For a query-style lookup, there
2861 is no file name, and the "key" is just the query. For query-style with a file
2862 name, we have to fish the file off the start of the query. For a single-key
2863 lookup, the key is the current IP address, masked appropriately, and
2864 reconverted to text form, with the mask appended. For IPv6 addresses, specify
2865 dot separators instead of colons, except when the lookup type is "iplsearch".
2866 */
2867
2868 if (mac_islookup(search_type, lookup_absfilequery))
2869 {
2870 filename = semicolon + 1;
2871 key = filename;
2872 while (*key != 0 && !isspace(*key)) key++;
2873 filename = string_copyn(filename, key - filename);
2874 while (isspace(*key)) key++;
2875 }
2876 else if (mac_islookup(search_type, lookup_querystyle))
2877 {
2878 filename = NULL;
2879 key = semicolon + 1;
2880 }
2881 else /* Single-key style */
2882 {
2883 int sep = (Ustrcmp(lookup_list[search_type]->name, "iplsearch") == 0)?
2884 ':' : '.';
2885 insize = host_aton(cb->host_address, incoming);
2886 host_mask(insize, incoming, mlen);
2887 (void)host_nmtoa(insize, incoming, mlen, buffer, sep);
2888 key = buffer;
2889 filename = semicolon + 1;
2890 }
2891
2892 /* Now do the actual lookup; note that there is no search_close() because
2893 of the caching arrangements. */
2894
2895 handle = search_open(filename, search_type, 0, NULL, NULL);
2896 if (handle == NULL) log_write(0, LOG_MAIN|LOG_PANIC_DIE, "%s",
2897 search_error_message);
2898 result = search_find(handle, filename, key, -1, NULL, 0, 0, NULL);
2899 if (valueptr != NULL) *valueptr = result;
2900 return (result != NULL)? OK : search_find_defer? DEFER: FAIL;
2901 }
2902
2903 /* The pattern is not an IP address or network reference of any kind. That is,
2904 it is a host name pattern. If this is an IP only match, there's an error in the
2905 host list. */
2906
2907 if (isiponly)
2908 {
2909 *error = US"cannot match host name in match_ip list";
2910 return ERROR;
2911 }
2912
2913 /* Check the characters of the pattern to see if they comprise only letters,
2914 digits, full stops, and hyphens (the constituents of domain names). Allow
2915 underscores, as they are all too commonly found. Sigh. Also, if
2916 allow_utf8_domains is set, allow top-bit characters. */
2917
2918 for (t = ss; *t != 0; t++)
2919 if (!isalnum(*t) && *t != '.' && *t != '-' && *t != '_' &&
2920 (!allow_utf8_domains || *t < 128)) break;
2921
2922 /* If the pattern is a complete domain name, with no fancy characters, look up
2923 its IP address and match against that. Note that a multi-homed host will add
2924 items to the chain. */
2925
2926 if (*t == 0)
2927 {
2928 int rc;
2929 host_item h;
2930 h.next = NULL;
2931 h.name = ss;
2932 h.address = NULL;
2933 h.mx = MX_NONE;
2934
2935 rc = host_find_byname(&h, NULL, HOST_FIND_QUALIFY_SINGLE, NULL, FALSE);
2936 if (rc == HOST_FOUND || rc == HOST_FOUND_LOCAL)
2937 {
2938 host_item *hh;
2939 for (hh = &h; hh != NULL; hh = hh->next)
2940 {
2941 if (host_is_in_net(hh->address, cb->host_address, 0)) return OK;
2942 }
2943 return FAIL;
2944 }
2945 if (rc == HOST_FIND_AGAIN) return DEFER;
2946 *error = string_sprintf("failed to find IP address for %s", ss);
2947 return ERROR;
2948 }
2949
2950 /* Almost all subsequent comparisons require the host name, and can be done
2951 using the general string matching function. When this function is called for
2952 outgoing hosts, the name is always given explicitly. If it is NULL, it means we
2953 must use sender_host_name and its aliases, looking them up if necessary. */
2954
2955 if (cb->host_name != NULL) /* Explicit host name given */
2956 return match_check_string(cb->host_name, ss, -1, TRUE, TRUE, TRUE,
2957 valueptr);
2958
2959 /* Host name not given; in principle we need the sender host name and its
2960 aliases. However, for query-style lookups, we do not need the name if the
2961 query does not contain $sender_host_name. From release 4.23, a reference to
2962 $sender_host_name causes it to be looked up, so we don't need to do the lookup
2963 on spec. */
2964
2965 if ((semicolon = Ustrchr(ss, ';')) != NULL)
2966 {
2967 uschar *affix;
2968 int partial, affixlen, starflags, id;
2969
2970 *semicolon = 0;
2971 id = search_findtype_partial(ss, &partial, &affix, &affixlen, &starflags);
2972 *semicolon=';';
2973
2974 if (id < 0) /* Unknown lookup type */
2975 {
2976 log_write(0, LOG_MAIN|LOG_PANIC, "%s in host list item \"%s\"",
2977 search_error_message, ss);
2978 return DEFER;
2979 }
2980 isquery = mac_islookup(id, lookup_querystyle|lookup_absfilequery);
2981 }
2982
2983 if (isquery)
2984 {
2985 switch(match_check_string(US"", ss, -1, TRUE, TRUE, TRUE, valueptr))
2986 {
2987 case OK: return OK;
2988 case DEFER: return DEFER;
2989 default: return FAIL;
2990 }
2991 }
2992
2993 /* Not a query-style lookup; must ensure the host name is present, and then we
2994 do a check on the name and all its aliases. */
2995
2996 if (sender_host_name == NULL)
2997 {
2998 HDEBUG(D_host_lookup)
2999 debug_printf("sender host name required, to match against %s\n", ss);
3000 if (host_lookup_failed || host_name_lookup() != OK)
3001 {
3002 *error = string_sprintf("failed to find host name for %s",
3003 sender_host_address);;
3004 return ERROR;
3005 }
3006 host_build_sender_fullhost();
3007 }
3008
3009 /* Match on the sender host name, using the general matching function */
3010
3011 switch(match_check_string(sender_host_name, ss, -1, TRUE, TRUE, TRUE,
3012 valueptr))
3013 {
3014 case OK: return OK;
3015 case DEFER: return DEFER;
3016 }
3017
3018 /* If there are aliases, try matching on them. */
3019
3020 aliases = sender_host_aliases;
3021 while (*aliases != NULL)
3022 {
3023 switch(match_check_string(*aliases++, ss, -1, TRUE, TRUE, TRUE, valueptr))
3024 {
3025 case OK: return OK;
3026 case DEFER: return DEFER;
3027 }
3028 }
3029 return FAIL;
3030 }
3031
3032
3033
3034
3035 /*************************************************
3036 * Check a specific host matches a host list *
3037 *************************************************/
3038
3039 /* This function is passed a host list containing items in a number of
3040 different formats and the identity of a host. Its job is to determine whether
3041 the given host is in the set of hosts defined by the list. The host name is
3042 passed as a pointer so that it can be looked up if needed and not already
3043 known. This is commonly the case when called from verify_check_host() to check
3044 an incoming connection. When called from elsewhere the host name should usually
3045 be set.
3046
3047 This function is now just a front end to match_check_list(), which runs common
3048 code for scanning a list. We pass it the check_host() function to perform a
3049 single test.
3050
3051 Arguments:
3052 listptr pointer to the host list
3053 cache_bits pointer to cache for named lists, or NULL
3054 host_name the host name or NULL, implying use sender_host_name and
3055 sender_host_aliases, looking them up if required
3056 host_address the IP address
3057 valueptr if not NULL, data from a lookup is passed back here
3058
3059 Returns: OK if the host is in the defined set
3060 FAIL if the host is not in the defined set,
3061 DEFER if a data lookup deferred (not a host lookup)
3062
3063 If the host name was needed in order to make a comparison, and could not be
3064 determined from the IP address, the result is FAIL unless the item
3065 "+allow_unknown" was met earlier in the list, in which case OK is returned. */
3066
3067 int
3068 verify_check_this_host(uschar **listptr, unsigned int *cache_bits,
3069 uschar *host_name, uschar *host_address, uschar **valueptr)
3070 {
3071 int rc;
3072 unsigned int *local_cache_bits = cache_bits;
3073 uschar *save_host_address = deliver_host_address;
3074 check_host_block cb;
3075 cb.host_name = host_name;
3076 cb.host_address = host_address;
3077
3078 if (valueptr != NULL) *valueptr = NULL;
3079
3080 /* If the host address starts off ::ffff: it is an IPv6 address in
3081 IPv4-compatible mode. Find the IPv4 part for checking against IPv4
3082 addresses. */
3083
3084 cb.host_ipv4 = (Ustrncmp(host_address, "::ffff:", 7) == 0)?
3085 host_address + 7 : host_address;
3086
3087 /* During the running of the check, put the IP address into $host_address. In
3088 the case of calls from the smtp transport, it will already be there. However,
3089 in other calls (e.g. when testing ignore_target_hosts), it won't. Just to be on
3090 the safe side, any existing setting is preserved, though as I write this
3091 (November 2004) I can't see any cases where it is actually needed. */
3092
3093 deliver_host_address = host_address;
3094 rc = match_check_list(
3095 listptr, /* the list */
3096 0, /* separator character */
3097 &hostlist_anchor, /* anchor pointer */
3098 &local_cache_bits, /* cache pointer */
3099 check_host, /* function for testing */
3100 &cb, /* argument for function */
3101 MCL_HOST, /* type of check */
3102 (host_address == sender_host_address)?
3103 US"host" : host_address, /* text for debugging */
3104 valueptr); /* where to pass back data */
3105 deliver_host_address = save_host_address;
3106 return rc;
3107 }
3108
3109
3110
3111
3112 /*************************************************
3113 * Check the remote host matches a list *
3114 *************************************************/
3115
3116 /* This is a front end to verify_check_this_host(), created because checking
3117 the remote host is a common occurrence. With luck, a good compiler will spot
3118 the tail recursion and optimize it. If there's no host address, this is
3119 command-line SMTP input - check against an empty string for the address.
3120
3121 Arguments:
3122 listptr pointer to the host list
3123
3124 Returns: the yield of verify_check_this_host(),
3125 i.e. OK, FAIL, or DEFER
3126 */
3127
3128 int
3129 verify_check_host(uschar **listptr)
3130 {
3131 return verify_check_this_host(listptr, sender_host_cache, NULL,
3132 (sender_host_address == NULL)? US"" : sender_host_address, NULL);
3133 }
3134
3135
3136
3137
3138
3139 /*************************************************
3140 * Invert an IP address *
3141 *************************************************/
3142
3143 /* Originally just used for DNS xBL lists, now also used for the
3144 reverse_ip expansion operator.
3145
3146 Arguments:
3147 buffer where to put the answer
3148 address the address to invert
3149 */
3150
3151 void
3152 invert_address(uschar *buffer, uschar *address)
3153 {
3154 int bin[4];
3155 uschar *bptr = buffer;
3156
3157 /* If this is an IPv4 address mapped into IPv6 format, adjust the pointer
3158 to the IPv4 part only. */
3159
3160 if (Ustrncmp(address, "::ffff:", 7) == 0) address += 7;
3161
3162 /* Handle IPv4 address: when HAVE_IPV6 is false, the result of host_aton() is
3163 always 1. */
3164
3165 if (host_aton(address, bin) == 1)
3166 {
3167 int i;
3168 int x = bin[0];
3169 for (i = 0; i < 4; i++)
3170 {
3171 sprintf(CS bptr, "%d.", x & 255);
3172 while (*bptr) bptr++;
3173 x >>= 8;
3174 }
3175 }
3176
3177 /* Handle IPv6 address. Actually, as far as I know, there are no IPv6 addresses
3178 in any DNS black lists, and the format in which they will be looked up is
3179 unknown. This is just a guess. */
3180
3181 #if HAVE_IPV6
3182 else
3183 {
3184 int i, j;
3185 for (j = 3; j >= 0; j--)
3186 {
3187 int x = bin[j];
3188 for (i = 0; i < 8; i++)
3189 {
3190 sprintf(CS bptr, "%x.", x & 15);
3191 while (*bptr) bptr++;
3192 x >>= 4;
3193 }
3194 }
3195 }
3196 #endif
3197
3198 /* Remove trailing period -- this is needed so that both arbitrary
3199 dnsbl keydomains and inverted addresses may be combined with the
3200 same format string, "%s.%s" */
3201
3202 *(--bptr) = 0;
3203 }
3204
3205
3206
3207 /*************************************************
3208 * Perform a single dnsbl lookup *
3209 *************************************************/
3210
3211 /* This function is called from verify_check_dnsbl() below. It is also called
3212 recursively from within itself when domain and domain_txt are different
3213 pointers, in order to get the TXT record from the alternate domain.
3214
3215 Arguments:
3216 domain the outer dnsbl domain
3217 domain_txt alternate domain to lookup TXT record on success; when the
3218 same domain is to be used, domain_txt == domain (that is,
3219 the pointers must be identical, not just the text)
3220 keydomain the current keydomain (for debug message)
3221 prepend subdomain to lookup (like keydomain, but
3222 reversed if IP address)
3223 iplist the list of matching IP addresses, or NULL for "any"
3224 bitmask true if bitmask matching is wanted
3225 match_type condition for 'succeed' result
3226 0 => Any RR in iplist (=)
3227 1 => No RR in iplist (!=)
3228 2 => All RRs in iplist (==)
3229 3 => Some RRs not in iplist (!==)
3230 the two bits are defined as MT_NOT and MT_ALL
3231 defer_return what to return for a defer
3232
3233 Returns: OK if lookup succeeded
3234 FAIL if not
3235 */
3236
3237 static int
3238 one_check_dnsbl(uschar *domain, uschar *domain_txt, uschar *keydomain,
3239 uschar *prepend, uschar *iplist, BOOL bitmask, int match_type,
3240 int defer_return)
3241 {
3242 dns_answer dnsa;
3243 dns_scan dnss;
3244 tree_node *t;
3245 dnsbl_cache_block *cb;
3246 int old_pool = store_pool;
3247 uschar query[256]; /* DNS domain max length */
3248
3249 /* Construct the specific query domainname */
3250
3251 if (!string_format(query, sizeof(query), "%s.%s", prepend, domain))
3252 {
3253 log_write(0, LOG_MAIN|LOG_PANIC, "dnslist query is too long "
3254 "(ignored): %s...", query);
3255 return FAIL;
3256 }
3257
3258 /* Look for this query in the cache. */
3259
3260 t = tree_search(dnsbl_cache, query);
3261
3262 /* If not cached from a previous lookup, we must do a DNS lookup, and
3263 cache the result in permanent memory. */
3264
3265 if (t == NULL)
3266 {
3267 store_pool = POOL_PERM;
3268
3269 /* Set up a tree entry to cache the lookup */
3270
3271 t = store_get(sizeof(tree_node) + Ustrlen(query));
3272 Ustrcpy(t->name, query);
3273 t->data.ptr = cb = store_get(sizeof(dnsbl_cache_block));
3274 (void)tree_insertnode(&dnsbl_cache, t);
3275
3276 /* Do the DNS loopup . */
3277
3278 HDEBUG(D_dnsbl) debug_printf("new DNS lookup for %s\n", query);
3279 cb->rc = dns_basic_lookup(&dnsa, query, T_A);
3280 cb->text_set = FALSE;
3281 cb->text = NULL;
3282 cb->rhs = NULL;
3283
3284 /* If the lookup succeeded, cache the RHS address. The code allows for
3285 more than one address - this was for complete generality and the possible
3286 use of A6 records. However, A6 records have been reduced to experimental
3287 status (August 2001) and may die out. So they may never get used at all,
3288 let alone in dnsbl records. However, leave the code here, just in case.
3289
3290 Quite apart from one A6 RR generating multiple addresses, there are DNS
3291 lists that return more than one A record, so we must handle multiple
3292 addresses generated in that way as well. */
3293
3294 if (cb->rc == DNS_SUCCEED)
3295 {
3296 dns_record *rr;
3297 dns_address **addrp = &(cb->rhs);
3298 for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS);
3299 rr != NULL;
3300 rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT))
3301 {
3302 if (rr->type == T_A)
3303 {
3304 dns_address *da = dns_address_from_rr(&dnsa, rr);
3305 if (da != NULL)
3306 {
3307 *addrp = da;
3308 while (da->next != NULL) da = da->next;
3309 addrp = &(da->next);
3310 }
3311 }
3312 }
3313
3314 /* If we didn't find any A records, change the return code. This can
3315 happen when there is a CNAME record but there are no A records for what
3316 it points to. */
3317
3318 if (cb->rhs == NULL) cb->rc = DNS_NODATA;
3319 }
3320
3321 store_pool = old_pool;
3322 }
3323
3324 /* Previous lookup was cached */
3325
3326 else
3327 {
3328 HDEBUG(D_dnsbl) debug_printf("using result of previous DNS lookup\n");
3329 cb = t->data.ptr;
3330 }
3331
3332 /* We now have the result of the DNS lookup, either newly done, or cached
3333 from a previous call. If the lookup succeeded, check against the address
3334 list if there is one. This may be a positive equality list (introduced by
3335 "="), a negative equality list (introduced by "!="), a positive bitmask
3336 list (introduced by "&"), or a negative bitmask list (introduced by "!&").*/
3337
3338 if (cb->rc == DNS_SUCCEED)
3339 {
3340 dns_address *da = NULL;
3341 uschar *addlist = cb->rhs->address;
3342
3343 /* For A and AAAA records, there may be multiple addresses from multiple
3344 records. For A6 records (currently not expected to be used) there may be
3345 multiple addresses from a single record. */
3346
3347 for (da = cb->rhs->next; da != NULL; da = da->next)
3348 addlist = string_sprintf("%s, %s", addlist, da->address);
3349
3350 HDEBUG(D_dnsbl) debug_printf("DNS lookup for %s succeeded (yielding %s)\n",
3351 query, addlist);
3352
3353 /* Address list check; this can be either for equality, or via a bitmask.
3354 In the latter case, all the bits must match. */
3355
3356 if (iplist != NULL)
3357 {
3358 for (da = cb->rhs; da != NULL; da = da->next)
3359 {
3360 int ipsep = ',';
3361 uschar ip[46];
3362 uschar *ptr = iplist;
3363 uschar *res;
3364
3365 /* Handle exact matching */
3366
3367 if (!bitmask)
3368 {
3369 while ((res = string_nextinlist(&ptr, &ipsep, ip, sizeof(ip))) != NULL)
3370 {
3371 if (Ustrcmp(CS da->address, ip) == 0) break;
3372 }
3373 }
3374
3375 /* Handle bitmask matching */
3376
3377 else
3378 {
3379 int address[4];
3380 int mask = 0;
3381
3382 /* At present, all known DNS blocking lists use A records, with
3383 IPv4 addresses on the RHS encoding the information they return. I
3384 wonder if this will linger on as the last vestige of IPv4 when IPv6
3385 is ubiquitous? Anyway, for now we use paranoia code to completely
3386 ignore IPv6 addresses. The default mask is 0, which always matches.
3387 We change this only for IPv4 addresses in the list. */
3388
3389 if (host_aton(da->address, address) == 1) mask = address[0];
3390
3391 /* Scan the returned addresses, skipping any that are IPv6 */
3392
3393 while ((res = string_nextinlist(&ptr, &ipsep, ip, sizeof(ip))) != NULL)
3394 {
3395 if (host_aton(ip, address) != 1) continue;
3396 if ((address[0] & mask) == address[0]) break;
3397 }
3398 }
3399
3400 /* If either
3401
3402 (a) An IP address in an any ('=') list matched, or
3403 (b) No IP address in an all ('==') list matched
3404
3405 then we're done searching. */
3406
3407 if (((match_type & MT_ALL) != 0) == (res == NULL)) break;
3408 }
3409
3410 /* If da == NULL, either
3411
3412 (a) No IP address in an any ('=') list matched, or
3413 (b) An IP address in an all ('==') list didn't match
3414
3415 so behave as if the DNSBL lookup had not succeeded, i.e. the host is not on
3416 the list. */
3417
3418 if ((match_type == MT_NOT || match_type == MT_ALL) != (da == NULL))
3419 {
3420 HDEBUG(D_dnsbl)
3421 {
3422 uschar *res = NULL;
3423 switch(match_type)
3424 {
3425 case 0:
3426 res = US"was no match";
3427 break;
3428 case MT_NOT:
3429 res = US"was an exclude match";
3430 break;
3431 case MT_ALL:
3432 res = US"was an IP address that did not match";
3433 break;
3434 case MT_NOT|MT_ALL:
3435 res = US"were no IP addresses that did not match";
3436 break;
3437 }
3438 debug_printf("=> but we are not accepting this block class because\n");
3439 debug_printf("=> there %s for %s%c%s\n",
3440 res,
3441 ((match_type & MT_ALL) == 0)? "" : "=",
3442 bitmask? '&' : '=', iplist);
3443 }
3444 return FAIL;
3445 }
3446 }
3447
3448 /* Either there was no IP list, or the record matched, implying that the
3449 domain is on the list. We now want to find a corresponding TXT record. If an
3450 alternate domain is specified for the TXT record, call this function
3451 recursively to look that up; this has the side effect of re-checking that
3452 there is indeed an A record at the alternate domain. */
3453
3454 if (domain_txt != domain)
3455 return one_check_dnsbl(domain_txt, domain_txt, keydomain, prepend, NULL,
3456 FALSE, match_type, defer_return);
3457
3458