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Merge branch 'SMTPUTF8_1516'. Bug 1516
[exim.git] / src / src / transports / smtp.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 #include "../exim.h"
9 #include "smtp.h"
10
11 #define PENDING 256
12 #define PENDING_DEFER (PENDING + DEFER)
13 #define PENDING_OK (PENDING + OK)
14
15
16 /* Options specific to the smtp transport. This transport also supports LMTP
17 over TCP/IP. The options must be in alphabetic order (note that "_" comes
18 before the lower case letters). Some live in the transport_instance block so as
19 to be publicly visible; these are flagged with opt_public. */
20
21 optionlist smtp_transport_options[] = {
22 { "*expand_multi_domain", opt_stringptr | opt_hidden | opt_public,
23 (void *)offsetof(transport_instance, expand_multi_domain) },
24 { "*expand_retry_include_ip_address", opt_stringptr | opt_hidden,
25 (void *)(offsetof(smtp_transport_options_block, expand_retry_include_ip_address)) },
26
27 { "address_retry_include_sender", opt_bool,
28 (void *)offsetof(smtp_transport_options_block, address_retry_include_sender) },
29 { "allow_localhost", opt_bool,
30 (void *)offsetof(smtp_transport_options_block, allow_localhost) },
31 { "authenticated_sender", opt_stringptr,
32 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
33 { "authenticated_sender_force", opt_bool,
34 (void *)offsetof(smtp_transport_options_block, authenticated_sender_force) },
35 { "command_timeout", opt_time,
36 (void *)offsetof(smtp_transport_options_block, command_timeout) },
37 { "connect_timeout", opt_time,
38 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
39 { "connection_max_messages", opt_int | opt_public,
40 (void *)offsetof(transport_instance, connection_max_messages) },
41 { "data_timeout", opt_time,
42 (void *)offsetof(smtp_transport_options_block, data_timeout) },
43 { "delay_after_cutoff", opt_bool,
44 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
45 #ifndef DISABLE_DKIM
46 { "dkim_canon", opt_stringptr,
47 (void *)offsetof(smtp_transport_options_block, dkim_canon) },
48 { "dkim_domain", opt_stringptr,
49 (void *)offsetof(smtp_transport_options_block, dkim_domain) },
50 { "dkim_private_key", opt_stringptr,
51 (void *)offsetof(smtp_transport_options_block, dkim_private_key) },
52 { "dkim_selector", opt_stringptr,
53 (void *)offsetof(smtp_transport_options_block, dkim_selector) },
54 { "dkim_sign_headers", opt_stringptr,
55 (void *)offsetof(smtp_transport_options_block, dkim_sign_headers) },
56 { "dkim_strict", opt_stringptr,
57 (void *)offsetof(smtp_transport_options_block, dkim_strict) },
58 #endif
59 { "dns_qualify_single", opt_bool,
60 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
61 { "dns_search_parents", opt_bool,
62 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
63 { "dnssec_request_domains", opt_stringptr,
64 (void *)offsetof(smtp_transport_options_block, dnssec_request_domains) },
65 { "dnssec_require_domains", opt_stringptr,
66 (void *)offsetof(smtp_transport_options_block, dnssec_require_domains) },
67 { "dscp", opt_stringptr,
68 (void *)offsetof(smtp_transport_options_block, dscp) },
69 { "fallback_hosts", opt_stringptr,
70 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
71 { "final_timeout", opt_time,
72 (void *)offsetof(smtp_transport_options_block, final_timeout) },
73 { "gethostbyname", opt_bool,
74 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
75 #ifdef SUPPORT_TLS
76 /* These are no longer honoured, as of Exim 4.80; for now, we silently
77 ignore; 4.83 will warn, and a later-still release will remove
78 these options, so that using them becomes an error. */
79 { "gnutls_require_kx", opt_stringptr,
80 (void *)offsetof(smtp_transport_options_block, gnutls_require_kx) },
81 { "gnutls_require_mac", opt_stringptr,
82 (void *)offsetof(smtp_transport_options_block, gnutls_require_mac) },
83 { "gnutls_require_protocols", opt_stringptr,
84 (void *)offsetof(smtp_transport_options_block, gnutls_require_proto) },
85 #endif
86 { "helo_data", opt_stringptr,
87 (void *)offsetof(smtp_transport_options_block, helo_data) },
88 { "hosts", opt_stringptr,
89 (void *)offsetof(smtp_transport_options_block, hosts) },
90 { "hosts_avoid_esmtp", opt_stringptr,
91 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
92 { "hosts_avoid_pipelining", opt_stringptr,
93 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
94 #ifdef SUPPORT_TLS
95 { "hosts_avoid_tls", opt_stringptr,
96 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
97 #endif
98 { "hosts_max_try", opt_int,
99 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
100 { "hosts_max_try_hardlimit", opt_int,
101 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
102 #ifdef SUPPORT_TLS
103 { "hosts_nopass_tls", opt_stringptr,
104 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
105 #endif
106 { "hosts_override", opt_bool,
107 (void *)offsetof(smtp_transport_options_block, hosts_override) },
108 { "hosts_randomize", opt_bool,
109 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
110 #if defined(SUPPORT_TLS) && !defined(DISABLE_OCSP)
111 { "hosts_request_ocsp", opt_stringptr,
112 (void *)offsetof(smtp_transport_options_block, hosts_request_ocsp) },
113 #endif
114 { "hosts_require_auth", opt_stringptr,
115 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
116 #ifdef SUPPORT_TLS
117 # ifdef EXPERIMENTAL_DANE
118 { "hosts_require_dane", opt_stringptr,
119 (void *)offsetof(smtp_transport_options_block, hosts_require_dane) },
120 # endif
121 # ifndef DISABLE_OCSP
122 { "hosts_require_ocsp", opt_stringptr,
123 (void *)offsetof(smtp_transport_options_block, hosts_require_ocsp) },
124 # endif
125 { "hosts_require_tls", opt_stringptr,
126 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
127 #endif
128 { "hosts_try_auth", opt_stringptr,
129 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
130 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
131 { "hosts_try_dane", opt_stringptr,
132 (void *)offsetof(smtp_transport_options_block, hosts_try_dane) },
133 #endif
134 #ifndef DISABLE_PRDR
135 { "hosts_try_prdr", opt_stringptr,
136 (void *)offsetof(smtp_transport_options_block, hosts_try_prdr) },
137 #endif
138 #ifdef SUPPORT_TLS
139 { "hosts_verify_avoid_tls", opt_stringptr,
140 (void *)offsetof(smtp_transport_options_block, hosts_verify_avoid_tls) },
141 #endif
142 { "interface", opt_stringptr,
143 (void *)offsetof(smtp_transport_options_block, interface) },
144 { "keepalive", opt_bool,
145 (void *)offsetof(smtp_transport_options_block, keepalive) },
146 { "lmtp_ignore_quota", opt_bool,
147 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
148 { "max_rcpt", opt_int | opt_public,
149 (void *)offsetof(transport_instance, max_addresses) },
150 { "multi_domain", opt_expand_bool | opt_public,
151 (void *)offsetof(transport_instance, multi_domain) },
152 { "port", opt_stringptr,
153 (void *)offsetof(smtp_transport_options_block, port) },
154 { "protocol", opt_stringptr,
155 (void *)offsetof(smtp_transport_options_block, protocol) },
156 { "retry_include_ip_address", opt_expand_bool,
157 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
158 { "serialize_hosts", opt_stringptr,
159 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
160 { "size_addition", opt_int,
161 (void *)offsetof(smtp_transport_options_block, size_addition) }
162 #ifdef EXPERIMENTAL_SOCKS
163 ,{ "socks_proxy", opt_stringptr,
164 (void *)offsetof(smtp_transport_options_block, socks_proxy) }
165 #endif
166 #ifdef SUPPORT_TLS
167 ,{ "tls_certificate", opt_stringptr,
168 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
169 { "tls_crl", opt_stringptr,
170 (void *)offsetof(smtp_transport_options_block, tls_crl) },
171 { "tls_dh_min_bits", opt_int,
172 (void *)offsetof(smtp_transport_options_block, tls_dh_min_bits) },
173 { "tls_privatekey", opt_stringptr,
174 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
175 { "tls_require_ciphers", opt_stringptr,
176 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
177 { "tls_sni", opt_stringptr,
178 (void *)offsetof(smtp_transport_options_block, tls_sni) },
179 { "tls_tempfail_tryclear", opt_bool,
180 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
181 { "tls_try_verify_hosts", opt_stringptr,
182 (void *)offsetof(smtp_transport_options_block, tls_try_verify_hosts) },
183 { "tls_verify_cert_hostnames", opt_stringptr,
184 (void *)offsetof(smtp_transport_options_block,tls_verify_cert_hostnames)},
185 { "tls_verify_certificates", opt_stringptr,
186 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) },
187 { "tls_verify_hosts", opt_stringptr,
188 (void *)offsetof(smtp_transport_options_block, tls_verify_hosts) }
189 #endif
190 };
191
192 /* Size of the options list. An extern variable has to be used so that its
193 address can appear in the tables drtables.c. */
194
195 int smtp_transport_options_count =
196 sizeof(smtp_transport_options)/sizeof(optionlist);
197
198 /* Default private options block for the smtp transport. */
199
200 smtp_transport_options_block smtp_transport_option_defaults = {
201 NULL, /* hosts */
202 NULL, /* fallback_hosts */
203 NULL, /* hostlist */
204 NULL, /* fallback_hostlist */
205 NULL, /* authenticated_sender */
206 US"$primary_hostname", /* helo_data */
207 NULL, /* interface */
208 NULL, /* port */
209 US"smtp", /* protocol */
210 NULL, /* DSCP */
211 NULL, /* serialize_hosts */
212 NULL, /* hosts_try_auth */
213 NULL, /* hosts_require_auth */
214 #ifdef EXPERIMENTAL_DANE
215 NULL, /* hosts_try_dane */
216 NULL, /* hosts_require_dane */
217 #endif
218 #ifndef DISABLE_PRDR
219 US"*", /* hosts_try_prdr */
220 #endif
221 #ifndef DISABLE_OCSP
222 US"*", /* hosts_request_ocsp (except under DANE; tls_client_start()) */
223 NULL, /* hosts_require_ocsp */
224 #endif
225 NULL, /* hosts_require_tls */
226 NULL, /* hosts_avoid_tls */
227 NULL, /* hosts_verify_avoid_tls */
228 NULL, /* hosts_avoid_pipelining */
229 NULL, /* hosts_avoid_esmtp */
230 NULL, /* hosts_nopass_tls */
231 5*60, /* command_timeout */
232 5*60, /* connect_timeout; shorter system default overrides */
233 5*60, /* data timeout */
234 10*60, /* final timeout */
235 1024, /* size_addition */
236 5, /* hosts_max_try */
237 50, /* hosts_max_try_hardlimit */
238 TRUE, /* address_retry_include_sender */
239 FALSE, /* allow_localhost */
240 FALSE, /* authenticated_sender_force */
241 FALSE, /* gethostbyname */
242 TRUE, /* dns_qualify_single */
243 FALSE, /* dns_search_parents */
244 NULL, /* dnssec_request_domains */
245 NULL, /* dnssec_require_domains */
246 TRUE, /* delay_after_cutoff */
247 FALSE, /* hosts_override */
248 FALSE, /* hosts_randomize */
249 TRUE, /* keepalive */
250 FALSE, /* lmtp_ignore_quota */
251 NULL, /* expand_retry_include_ip_address */
252 TRUE /* retry_include_ip_address */
253 #ifdef EXPERIMENTAL_SOCKS
254 ,NULL /* socks_proxy */
255 #endif
256 #ifdef SUPPORT_TLS
257 ,NULL, /* tls_certificate */
258 NULL, /* tls_crl */
259 NULL, /* tls_privatekey */
260 NULL, /* tls_require_ciphers */
261 NULL, /* gnutls_require_kx */
262 NULL, /* gnutls_require_mac */
263 NULL, /* gnutls_require_proto */
264 NULL, /* tls_sni */
265 US"system", /* tls_verify_certificates */
266 EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
267 /* tls_dh_min_bits */
268 TRUE, /* tls_tempfail_tryclear */
269 NULL, /* tls_verify_hosts */
270 US"*", /* tls_try_verify_hosts */
271 US"*" /* tls_verify_cert_hostnames */
272 #endif
273 #ifndef DISABLE_DKIM
274 ,NULL, /* dkim_canon */
275 NULL, /* dkim_domain */
276 NULL, /* dkim_private_key */
277 NULL, /* dkim_selector */
278 NULL, /* dkim_sign_headers */
279 NULL /* dkim_strict */
280 #endif
281 };
282
283 /* some DSN flags for use later */
284
285 static int rf_list[] = {rf_notify_never, rf_notify_success,
286 rf_notify_failure, rf_notify_delay };
287
288 static uschar *rf_names[] = { US"NEVER", US"SUCCESS", US"FAILURE", US"DELAY" };
289
290
291
292 /* Local statics */
293
294 static uschar *smtp_command; /* Points to last cmd for error messages */
295 static uschar *mail_command; /* Points to MAIL cmd for error messages */
296 static BOOL update_waiting; /* TRUE to update the "wait" database */
297
298
299 /*************************************************
300 * Setup entry point *
301 *************************************************/
302
303 /* This function is called when the transport is about to be used,
304 but before running it in a sub-process. It is used for two things:
305
306 (1) To set the fallback host list in addresses, when delivering.
307 (2) To pass back the interface, port, protocol, and other options, for use
308 during callout verification.
309
310 Arguments:
311 tblock pointer to the transport instance block
312 addrlist list of addresses about to be transported
313 tf if not NULL, pointer to block in which to return options
314 uid the uid that will be set (not used)
315 gid the gid that will be set (not used)
316 errmsg place for error message (not used)
317
318 Returns: OK always (FAIL, DEFER not used)
319 */
320
321 static int
322 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
323 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
324 {
325 smtp_transport_options_block *ob =
326 (smtp_transport_options_block *)(tblock->options_block);
327
328 errmsg = errmsg; /* Keep picky compilers happy */
329 uid = uid;
330 gid = gid;
331
332 /* Pass back options if required. This interface is getting very messy. */
333
334 if (tf != NULL)
335 {
336 tf->interface = ob->interface;
337 tf->port = ob->port;
338 tf->protocol = ob->protocol;
339 tf->hosts = ob->hosts;
340 tf->hosts_override = ob->hosts_override;
341 tf->hosts_randomize = ob->hosts_randomize;
342 tf->gethostbyname = ob->gethostbyname;
343 tf->qualify_single = ob->dns_qualify_single;
344 tf->search_parents = ob->dns_search_parents;
345 tf->helo_data = ob->helo_data;
346 }
347
348 /* Set the fallback host list for all the addresses that don't have fallback
349 host lists, provided that the local host wasn't present in the original host
350 list. */
351
352 if (!testflag(addrlist, af_local_host_removed))
353 {
354 for (; addrlist != NULL; addrlist = addrlist->next)
355 if (addrlist->fallback_hosts == NULL)
356 addrlist->fallback_hosts = ob->fallback_hostlist;
357 }
358
359 return OK;
360 }
361
362
363
364 /*************************************************
365 * Initialization entry point *
366 *************************************************/
367
368 /* Called for each instance, after its options have been read, to
369 enable consistency checks to be done, or anything else that needs
370 to be set up.
371
372 Argument: pointer to the transport instance block
373 Returns: nothing
374 */
375
376 void
377 smtp_transport_init(transport_instance *tblock)
378 {
379 smtp_transport_options_block *ob =
380 (smtp_transport_options_block *)(tblock->options_block);
381
382 /* Retry_use_local_part defaults FALSE if unset */
383
384 if (tblock->retry_use_local_part == TRUE_UNSET)
385 tblock->retry_use_local_part = FALSE;
386
387 /* Set the default port according to the protocol */
388
389 if (ob->port == NULL)
390 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
391 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
392
393 /* Set up the setup entry point, to be called before subprocesses for this
394 transport. */
395
396 tblock->setup = smtp_transport_setup;
397
398 /* Complain if any of the timeouts are zero. */
399
400 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
401 ob->final_timeout <= 0)
402 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
403 "command, data, or final timeout value is zero for %s transport",
404 tblock->name);
405
406 /* If hosts_override is set and there are local hosts, set the global
407 flag that stops verify from showing router hosts. */
408
409 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
410
411 /* If there are any fallback hosts listed, build a chain of host items
412 for them, but do not do any lookups at this time. */
413
414 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
415
416 #ifdef SUPPORT_TLS
417 if ( ob->gnutls_require_kx
418 || ob->gnutls_require_mac
419 || ob->gnutls_require_proto)
420 log_write(0, LOG_MAIN, "WARNING: smtp transport options"
421 " gnutls_require_kx, gnutls_require_mac and gnutls_require_protocols"
422 " are obsolete\n");
423 #endif
424 }
425
426
427
428
429
430 /*************************************************
431 * Set delivery info into all active addresses *
432 *************************************************/
433
434 /* Only addresses whose status is >= PENDING are relevant. A lesser
435 status means that an address is not currently being processed.
436
437 Arguments:
438 addrlist points to a chain of addresses
439 errno_value to put in each address's errno field
440 msg to put in each address's message field
441 rc to put in each address's transport_return field
442 pass_message if TRUE, set the "pass message" flag in the address
443 host if set, mark addrs as having used this host
444
445 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
446 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
447 this particular type of timeout.
448
449 Returns: nothing
450 */
451
452 static void
453 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
454 BOOL pass_message, host_item * host)
455 {
456 address_item *addr;
457 int orvalue = 0;
458 if (errno_value == ERRNO_CONNECTTIMEOUT)
459 {
460 errno_value = ETIMEDOUT;
461 orvalue = RTEF_CTOUT;
462 }
463 for (addr = addrlist; addr != NULL; addr = addr->next)
464 if (addr->transport_return >= PENDING)
465 {
466 addr->basic_errno = errno_value;
467 addr->more_errno |= orvalue;
468 if (msg != NULL)
469 {
470 addr->message = msg;
471 if (pass_message) setflag(addr, af_pass_message);
472 }
473 addr->transport_return = rc;
474 if (host)
475 addr->host_used = host;
476 }
477 }
478
479
480
481 /*************************************************
482 * Check an SMTP response *
483 *************************************************/
484
485 /* This function is given an errno code and the SMTP response buffer
486 to analyse, together with the host identification for generating messages. It
487 sets an appropriate message and puts the first digit of the response code into
488 the yield variable. If no response was actually read, a suitable digit is
489 chosen.
490
491 Arguments:
492 host the current host, to get its name for messages
493 errno_value pointer to the errno value
494 more_errno from the top address for use with ERRNO_FILTER_FAIL
495 buffer the SMTP response buffer
496 yield where to put a one-digit SMTP response code
497 message where to put an errror message
498 pass_message set TRUE if message is an SMTP response
499
500 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
501 */
502
503 static BOOL
504 check_response(host_item *host, int *errno_value, int more_errno,
505 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
506 {
507 uschar *pl = US"";
508
509 if (smtp_use_pipelining &&
510 (Ustrcmp(smtp_command, "MAIL") == 0 ||
511 Ustrcmp(smtp_command, "RCPT") == 0 ||
512 Ustrcmp(smtp_command, "DATA") == 0))
513 pl = US"pipelined ";
514
515 *yield = '4'; /* Default setting is to give a temporary error */
516
517 /* Handle response timeout */
518
519 if (*errno_value == ETIMEDOUT)
520 {
521 *message = US string_sprintf("SMTP timeout after %s%s",
522 pl, smtp_command);
523 if (transport_count > 0)
524 *message = US string_sprintf("%s (%d bytes written)", *message,
525 transport_count);
526 return FALSE;
527 }
528
529 /* Handle malformed SMTP response */
530
531 if (*errno_value == ERRNO_SMTPFORMAT)
532 {
533 const uschar *malfresp = string_printing(buffer);
534 while (isspace(*malfresp)) malfresp++;
535 *message = *malfresp == 0
536 ? string_sprintf("Malformed SMTP reply (an empty line) "
537 "in response to %s%s", pl, smtp_command)
538 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
539 pl, smtp_command, malfresp);
540 return FALSE;
541 }
542
543 /* Handle a failed filter process error; can't send QUIT as we mustn't
544 end the DATA. */
545
546 if (*errno_value == ERRNO_FILTER_FAIL)
547 {
548 *message = US string_sprintf("transport filter process failed (%d)%s",
549 more_errno,
550 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
551 return FALSE;
552 }
553
554 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
555 end the DATA. */
556
557 if (*errno_value == ERRNO_CHHEADER_FAIL)
558 {
559 *message =
560 US string_sprintf("failed to expand headers_add or headers_remove: %s",
561 expand_string_message);
562 return FALSE;
563 }
564
565 /* Handle failure to write a complete data block */
566
567 if (*errno_value == ERRNO_WRITEINCOMPLETE)
568 {
569 *message = US string_sprintf("failed to write a data block");
570 return FALSE;
571 }
572
573 #ifdef EXPERIMENTAL_INTERNATIONAL
574 /* Handle lack of advertised SMTPUTF8, for international message */
575 if (*errno_value == ERRNO_UTF8_FWD)
576 {
577 *message = US string_sprintf("utf8 support required but not offered for forwarding");
578 DEBUG(D_deliver|D_transport) debug_printf("%s\n", *message);
579 return TRUE;
580 }
581 #endif
582
583 /* Handle error responses from the remote mailer. */
584
585 if (buffer[0] != 0)
586 {
587 const uschar *s = string_printing(buffer);
588 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
589 "%s", pl, smtp_command, s);
590 *pass_message = TRUE;
591 *yield = buffer[0];
592 return TRUE;
593 }
594
595 /* No data was read. If there is no errno, this must be the EOF (i.e.
596 connection closed) case, which causes deferral. An explicit connection reset
597 error has the same effect. Otherwise, put the host's identity in the message,
598 leaving the errno value to be interpreted as well. In all cases, we have to
599 assume the connection is now dead. */
600
601 if (*errno_value == 0 || *errno_value == ECONNRESET)
602 {
603 *errno_value = ERRNO_SMTPCLOSED;
604 *message = US string_sprintf("Remote host closed connection "
605 "in response to %s%s", pl, smtp_command);
606 }
607 else *message = US string_sprintf("%s [%s]", host->name, host->address);
608
609 return FALSE;
610 }
611
612
613
614 /*************************************************
615 * Write error message to logs *
616 *************************************************/
617
618 /* This writes to the main log and to the message log.
619
620 Arguments:
621 addr the address item containing error information
622 host the current host
623
624 Returns: nothing
625 */
626
627 static void
628 write_logs(address_item *addr, host_item *host)
629 {
630 uschar * message = string_sprintf("H=%s [%s]", host->name, host->address);
631
632 if (addr->message)
633 {
634 message = string_sprintf("%s: %s", message, addr->message);
635 if (addr->basic_errno > 0)
636 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
637 log_write(0, LOG_MAIN, "%s", message);
638 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
639 }
640 else
641 {
642 if (log_extra_selector & LX_outgoing_port)
643 message = string_sprintf("%s:%d", message,
644 host->port == PORT_NONE ? 25 : host->port);
645 log_write(0, LOG_MAIN, "%s %s", message, strerror(addr->basic_errno));
646 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), message,
647 strerror(addr->basic_errno));
648 }
649 }
650
651 static void
652 msglog_line(host_item * host, uschar * message)
653 {
654 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
655 host->name, host->address, message);
656 }
657
658
659
660 #ifdef EXPERIMENTAL_EVENT
661 /*************************************************
662 * Post-defer action *
663 *************************************************/
664
665 /* This expands an arbitrary per-transport string.
666 It might, for example, be used to write to the database log.
667
668 Arguments:
669 addr the address item containing error information
670 host the current host
671
672 Returns: nothing
673 */
674
675 static void
676 deferred_event_raise(address_item *addr, host_item *host)
677 {
678 uschar * action = addr->transport->event_action;
679 const uschar * save_domain;
680 uschar * save_local;
681
682 if (!action)
683 return;
684
685 save_domain = deliver_domain;
686 save_local = deliver_localpart;
687
688 /*XXX would ip & port already be set up? */
689 deliver_host_address = string_copy(host->address);
690 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
691 event_defer_errno = addr->basic_errno;
692
693 router_name = addr->router->name;
694 transport_name = addr->transport->name;
695 deliver_domain = addr->domain;
696 deliver_localpart = addr->local_part;
697
698 (void) event_raise(action, US"msg:host:defer",
699 addr->message
700 ? addr->basic_errno > 0
701 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
702 : string_copy(addr->message)
703 : addr->basic_errno > 0
704 ? string_copy(US strerror(addr->basic_errno))
705 : NULL);
706
707 deliver_localpart = save_local;
708 deliver_domain = save_domain;
709 router_name = transport_name = NULL;
710 }
711 #endif
712
713 /*************************************************
714 * Synchronize SMTP responses *
715 *************************************************/
716
717 /* This function is called from smtp_deliver() to receive SMTP responses from
718 the server, and match them up with the commands to which they relate. When
719 PIPELINING is not in use, this function is called after every command, and is
720 therefore somewhat over-engineered, but it is simpler to use a single scheme
721 that works both with and without PIPELINING instead of having two separate sets
722 of code.
723
724 The set of commands that are buffered up with pipelining may start with MAIL
725 and may end with DATA; in between are RCPT commands that correspond to the
726 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
727 etc.) are never buffered.
728
729 Errors after MAIL or DATA abort the whole process leaving the response in the
730 buffer. After MAIL, pending responses are flushed, and the original command is
731 re-instated in big_buffer for error messages. For RCPT commands, the remote is
732 permitted to reject some recipient addresses while accepting others. However
733 certain errors clearly abort the whole process. Set the value in
734 transport_return to PENDING_OK if the address is accepted. If there is a
735 subsequent general error, it will get reset accordingly. If not, it will get
736 converted to OK at the end.
737
738 Arguments:
739 addrlist the complete address list
740 include_affixes TRUE if affixes include in RCPT
741 sync_addr ptr to the ptr of the one to start scanning at (updated)
742 host the host we are connected to
743 count the number of responses to read
744 address_retry_
745 include_sender true if 4xx retry is to include the sender it its key
746 pending_MAIL true if the first response is for MAIL
747 pending_DATA 0 if last command sent was not DATA
748 +1 if previously had a good recipient
749 -1 if not previously had a good recipient
750 inblock incoming SMTP block
751 timeout timeout value
752 buffer buffer for reading response
753 buffsize size of buffer
754
755 Returns: 3 if at least one address had 2xx and one had 5xx
756 2 if at least one address had 5xx but none had 2xx
757 1 if at least one host had a 2xx response, but none had 5xx
758 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
759 -1 timeout while reading RCPT response
760 -2 I/O or other non-response error for RCPT
761 -3 DATA or MAIL failed - errno and buffer set
762 */
763
764 static int
765 sync_responses(address_item *addrlist, BOOL include_affixes,
766 address_item **sync_addr, host_item *host, int count,
767 BOOL address_retry_include_sender, BOOL pending_MAIL,
768 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
769 int buffsize)
770 {
771 address_item *addr = *sync_addr;
772 int yield = 0;
773
774 /* Handle the response for a MAIL command. On error, reinstate the original
775 command in big_buffer for error message use, and flush any further pending
776 responses before returning, except after I/O errors and timeouts. */
777
778 if (pending_MAIL)
779 {
780 count--;
781 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
782 {
783 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
784 if (errno == 0 && buffer[0] != 0)
785 {
786 uschar flushbuffer[4096];
787 int save_errno = 0;
788 if (buffer[0] == '4')
789 {
790 save_errno = ERRNO_MAIL4XX;
791 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
792 }
793 while (count-- > 0)
794 {
795 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
796 '2', timeout)
797 && (errno != 0 || flushbuffer[0] == 0))
798 break;
799 }
800 errno = save_errno;
801 }
802
803 if (pending_DATA) count--; /* Number of RCPT responses to come */
804 while (count-- > 0) /* Mark any pending addrs with the host used */
805 {
806 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
807 addr->host_used = host;
808 addr = addr->next;
809 }
810 return -3;
811 }
812 }
813
814 if (pending_DATA) count--; /* Number of RCPT responses to come */
815
816 /* Read and handle the required number of RCPT responses, matching each one up
817 with an address by scanning for the next address whose status is PENDING_DEFER.
818 */
819
820 while (count-- > 0)
821 {
822 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
823
824 /* The address was accepted */
825 addr->host_used = host;
826
827 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
828 {
829 yield |= 1;
830 addr->transport_return = PENDING_OK;
831
832 /* If af_dr_retry_exists is set, there was a routing delay on this address;
833 ensure that any address-specific retry record is expunged. We do this both
834 for the basic key and for the version that also includes the sender. */
835
836 if (testflag(addr, af_dr_retry_exists))
837 {
838 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
839 sender_address);
840 retry_add_item(addr, altkey, rf_delete);
841 retry_add_item(addr, addr->address_retry_key, rf_delete);
842 }
843 }
844
845 /* Timeout while reading the response */
846
847 else if (errno == ETIMEDOUT)
848 {
849 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
850 transport_rcpt_address(addr, include_affixes));
851 set_errno(addrlist, ETIMEDOUT, message, DEFER, FALSE, NULL);
852 retry_add_item(addr, addr->address_retry_key, 0);
853 update_waiting = FALSE;
854 return -1;
855 }
856
857 /* Handle other errors in obtaining an SMTP response by returning -1. This
858 will cause all the addresses to be deferred. Restore the SMTP command in
859 big_buffer for which we are checking the response, so the error message
860 makes sense. */
861
862 else if (errno != 0 || buffer[0] == 0)
863 {
864 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
865 transport_rcpt_address(addr, include_affixes));
866 return -2;
867 }
868
869 /* Handle SMTP permanent and temporary response codes. */
870
871 else
872 {
873 addr->message =
874 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
875 "%s", transport_rcpt_address(addr, include_affixes),
876 string_printing(buffer));
877 setflag(addr, af_pass_message);
878 msglog_line(host, addr->message);
879
880 /* The response was 5xx */
881
882 if (buffer[0] == '5')
883 {
884 addr->transport_return = FAIL;
885 yield |= 2;
886 }
887
888 /* The response was 4xx */
889
890 else
891 {
892 addr->transport_return = DEFER;
893 addr->basic_errno = ERRNO_RCPT4XX;
894 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
895
896 /* Log temporary errors if there are more hosts to be tried.
897 If not, log this last one in the == line. */
898
899 if (host->next)
900 log_write(0, LOG_MAIN, "H=%s [%s]: %s", host->name, host->address, addr->message);
901
902 /* Do not put this message on the list of those waiting for specific
903 hosts, as otherwise it is likely to be tried too often. */
904
905 update_waiting = FALSE;
906
907 /* Add a retry item for the address so that it doesn't get tried again
908 too soon. If address_retry_include_sender is true, add the sender address
909 to the retry key. */
910
911 if (address_retry_include_sender)
912 {
913 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
914 sender_address);
915 retry_add_item(addr, altkey, 0);
916 }
917 else retry_add_item(addr, addr->address_retry_key, 0);
918 }
919 }
920 } /* Loop for next RCPT response */
921
922 /* Update where to start at for the next block of responses, unless we
923 have already handled all the addresses. */
924
925 if (addr != NULL) *sync_addr = addr->next;
926
927 /* Handle a response to DATA. If we have not had any good recipients, either
928 previously or in this block, the response is ignored. */
929
930 if (pending_DATA != 0 &&
931 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
932 {
933 int code;
934 uschar *msg;
935 BOOL pass_message;
936 if (pending_DATA > 0 || (yield & 1) != 0)
937 {
938 if (errno == 0 && buffer[0] == '4')
939 {
940 errno = ERRNO_DATA4XX;
941 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
942 }
943 return -3;
944 }
945 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
946 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
947 "is in use and there were no good recipients\n", msg);
948 }
949
950 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
951 present) received 3xx. If any RCPTs were handled and yielded anything other
952 than 4xx, yield will be set non-zero. */
953
954 return yield;
955 }
956
957
958
959 /* Do the client side of smtp-level authentication */
960 /*
961 Arguments:
962 buffer EHLO response from server (gets overwritten)
963 addrlist chain of potential addresses to deliver
964 host host to deliver to
965 ob transport options
966 ibp, obp comms channel control blocks
967
968 Returns:
969 OK Success, or failed (but not required): global "smtp_authenticated" set
970 DEFER Failed authentication (and was required)
971 ERROR Internal problem
972
973 FAIL_SEND Failed communications - transmit
974 FAIL - response
975 */
976
977 int
978 smtp_auth(uschar *buffer, unsigned bufsize, address_item *addrlist, host_item *host,
979 smtp_transport_options_block *ob, BOOL is_esmtp,
980 smtp_inblock *ibp, smtp_outblock *obp)
981 {
982 int require_auth;
983 uschar *fail_reason = US"server did not advertise AUTH support";
984
985 smtp_authenticated = FALSE;
986 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
987 require_auth = verify_check_given_host(&ob->hosts_require_auth, host);
988
989 if (is_esmtp && !regex_AUTH) regex_AUTH =
990 regex_must_compile(US"\\n250[\\s\\-]AUTH\\s+([\\-\\w\\s]+)(?:\\n|$)",
991 FALSE, TRUE);
992
993 if (is_esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
994 {
995 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
996 expand_nmax = -1; /* reset */
997
998 /* Must not do this check until after we have saved the result of the
999 regex match above. */
1000
1001 if (require_auth == OK ||
1002 verify_check_given_host(&ob->hosts_try_auth, host) == OK)
1003 {
1004 auth_instance *au;
1005 fail_reason = US"no common mechanisms were found";
1006
1007 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1008
1009 /* Scan the configured authenticators looking for one which is configured
1010 for use as a client, which is not suppressed by client_condition, and
1011 whose name matches an authentication mechanism supported by the server.
1012 If one is found, attempt to authenticate by calling its client function.
1013 */
1014
1015 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1016 {
1017 uschar *p = names;
1018 if (!au->client ||
1019 (au->client_condition != NULL &&
1020 !expand_check_condition(au->client_condition, au->name,
1021 US"client authenticator")))
1022 {
1023 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1024 au->name,
1025 (au->client)? "client_condition is false" :
1026 "not configured as a client");
1027 continue;
1028 }
1029
1030 /* Loop to scan supported server mechanisms */
1031
1032 while (*p != 0)
1033 {
1034 int rc;
1035 int len = Ustrlen(au->public_name);
1036 while (isspace(*p)) p++;
1037
1038 if (strncmpic(au->public_name, p, len) != 0 ||
1039 (p[len] != 0 && !isspace(p[len])))
1040 {
1041 while (*p != 0 && !isspace(*p)) p++;
1042 continue;
1043 }
1044
1045 /* Found data for a listed mechanism. Call its client entry. Set
1046 a flag in the outblock so that data is overwritten after sending so
1047 that reflections don't show it. */
1048
1049 fail_reason = US"authentication attempt(s) failed";
1050 obp->authenticating = TRUE;
1051 rc = (au->info->clientcode)(au, ibp, obp,
1052 ob->command_timeout, buffer, bufsize);
1053 obp->authenticating = FALSE;
1054 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1055 au->name, rc);
1056
1057 /* A temporary authentication failure must hold up delivery to
1058 this host. After a permanent authentication failure, we carry on
1059 to try other authentication methods. If all fail hard, try to
1060 deliver the message unauthenticated unless require_auth was set. */
1061
1062 switch(rc)
1063 {
1064 case OK:
1065 smtp_authenticated = TRUE; /* stops the outer loop */
1066 client_authenticator = au->name;
1067 if (au->set_client_id != NULL)
1068 client_authenticated_id = expand_string(au->set_client_id);
1069 break;
1070
1071 /* Failure after writing a command */
1072
1073 case FAIL_SEND:
1074 return FAIL_SEND;
1075
1076 /* Failure after reading a response */
1077
1078 case FAIL:
1079 if (errno != 0 || buffer[0] != '5') return FAIL;
1080 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1081 au->name, host->name, host->address, buffer);
1082 break;
1083
1084 /* Failure by some other means. In effect, the authenticator
1085 decided it wasn't prepared to handle this case. Typically this
1086 is the result of "fail" in an expansion string. Do we need to
1087 log anything here? Feb 2006: a message is now put in the buffer
1088 if logging is required. */
1089
1090 case CANCELLED:
1091 if (*buffer != 0)
1092 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1093 "authentication H=%s [%s] %s", au->name, host->name,
1094 host->address, buffer);
1095 break;
1096
1097 /* Internal problem, message in buffer. */
1098
1099 case ERROR:
1100 set_errno(addrlist, ERRNO_AUTHPROB, string_copy(buffer),
1101 DEFER, FALSE, NULL);
1102 return ERROR;
1103 }
1104
1105 break; /* If not authenticated, try next authenticator */
1106 } /* Loop for scanning supported server mechanisms */
1107 } /* Loop for further authenticators */
1108 }
1109 }
1110
1111 /* If we haven't authenticated, but are required to, give up. */
1112
1113 if (require_auth == OK && !smtp_authenticated)
1114 {
1115 set_errno(addrlist, ERRNO_AUTHFAIL,
1116 string_sprintf("authentication required but %s", fail_reason), DEFER,
1117 FALSE, NULL);
1118 return DEFER;
1119 }
1120
1121 return OK;
1122 }
1123
1124
1125 /* Construct AUTH appendix string for MAIL TO */
1126 /*
1127 Arguments
1128 buffer to build string
1129 addrlist chain of potential addresses to deliver
1130 ob transport options
1131
1132 Globals smtp_authenticated
1133 client_authenticated_sender
1134 Return True on error, otherwise buffer has (possibly empty) terminated string
1135 */
1136
1137 BOOL
1138 smtp_mail_auth_str(uschar *buffer, unsigned bufsize, address_item *addrlist,
1139 smtp_transport_options_block *ob)
1140 {
1141 uschar *local_authenticated_sender = authenticated_sender;
1142
1143 #ifdef notdef
1144 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n", authenticated_sender, ob->authenticated_sender, smtp_authenticated?"Y":"N");
1145 #endif
1146
1147 if (ob->authenticated_sender != NULL)
1148 {
1149 uschar *new = expand_string(ob->authenticated_sender);
1150 if (new == NULL)
1151 {
1152 if (!expand_string_forcedfail)
1153 {
1154 uschar *message = string_sprintf("failed to expand "
1155 "authenticated_sender: %s", expand_string_message);
1156 set_errno(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, NULL);
1157 return TRUE;
1158 }
1159 }
1160 else if (new[0] != 0) local_authenticated_sender = new;
1161 }
1162
1163 /* Add the authenticated sender address if present */
1164
1165 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1166 local_authenticated_sender != NULL)
1167 {
1168 string_format(buffer, bufsize, " AUTH=%s",
1169 auth_xtextencode(local_authenticated_sender,
1170 Ustrlen(local_authenticated_sender)));
1171 client_authenticated_sender = string_copy(local_authenticated_sender);
1172 }
1173 else
1174 *buffer= 0;
1175
1176 return FALSE;
1177 }
1178
1179
1180
1181 #ifdef EXPERIMENTAL_DANE
1182 int
1183 tlsa_lookup(const host_item * host, dns_answer * dnsa,
1184 BOOL dane_required, BOOL * dane)
1185 {
1186 /* move this out to host.c given the similarity to dns_lookup() ? */
1187 uschar buffer[300];
1188 const uschar * fullname = buffer;
1189
1190 /* TLSA lookup string */
1191 (void)sprintf(CS buffer, "_%d._tcp.%.256s", host->port, host->name);
1192
1193 switch (dns_lookup(dnsa, buffer, T_TLSA, &fullname))
1194 {
1195 case DNS_AGAIN:
1196 return DEFER; /* just defer this TLS'd conn */
1197
1198 default:
1199 case DNS_FAIL:
1200 if (dane_required)
1201 {
1202 log_write(0, LOG_MAIN, "DANE error: TLSA lookup failed");
1203 return FAIL;
1204 }
1205 break;
1206
1207 case DNS_SUCCEED:
1208 if (!dns_is_secure(dnsa))
1209 {
1210 log_write(0, LOG_MAIN, "DANE error: TLSA lookup not DNSSEC");
1211 return DEFER;
1212 }
1213 *dane = TRUE;
1214 break;
1215 }
1216 return OK;
1217 }
1218 #endif
1219
1220
1221
1222 typedef struct smtp_compare_s
1223 {
1224 uschar *current_sender_address;
1225 struct transport_instance *tblock;
1226 } smtp_compare_t;
1227
1228 /*
1229 Create a unique string that identifies this message, it is based on
1230 sender_address, helo_data and tls_certificate if enabled. */
1231
1232 static uschar *
1233 smtp_local_identity(uschar * sender, struct transport_instance * tblock)
1234 {
1235 address_item * addr1;
1236 uschar * if1 = US"";
1237 uschar * helo1 = US"";
1238 #ifdef SUPPORT_TLS
1239 uschar * tlsc1 = US"";
1240 #endif
1241 uschar * save_sender_address = sender_address;
1242 uschar * local_identity = NULL;
1243 smtp_transport_options_block * ob =
1244 (smtp_transport_options_block *)tblock->options_block;
1245
1246 sender_address = sender;
1247
1248 addr1 = deliver_make_addr (sender, TRUE);
1249 deliver_set_expansions(addr1);
1250
1251 if (ob->interface)
1252 if1 = expand_string(ob->interface);
1253
1254 if (ob->helo_data)
1255 helo1 = expand_string(ob->helo_data);
1256
1257 #ifdef SUPPORT_TLS
1258 if (ob->tls_certificate)
1259 tlsc1 = expand_string(ob->tls_certificate);
1260 local_identity = string_sprintf ("%s^%s^%s", if1, helo1, tlsc1);
1261 #else
1262 local_identity = string_sprintf ("%s^%s", if1, helo1);
1263 #endif
1264
1265 deliver_set_expansions(NULL);
1266 sender_address = save_sender_address;
1267
1268 return local_identity;
1269 }
1270
1271
1272
1273 /* This routine is a callback that is called from transport_check_waiting.
1274 This function will evaluate the incoming message versus the previous
1275 message. If the incoming message is using a different local identity then
1276 we will veto this new message. */
1277
1278 static BOOL
1279 smtp_are_same_identities(uschar * message_id, smtp_compare_t * s_compare)
1280 {
1281 uschar * save_sender_address = sender_address;
1282 uschar * current_local_identity =
1283 smtp_local_identity(s_compare->current_sender_address, s_compare->tblock);
1284 uschar * new_sender_address = deliver_get_sender_address(message_id);
1285 uschar * message_local_identity =
1286 smtp_local_identity(new_sender_address, s_compare->tblock);
1287
1288 sender_address = save_sender_address;
1289
1290 return Ustrcmp(current_local_identity, message_local_identity) == 0;
1291 }
1292
1293
1294
1295 /*************************************************
1296 * Deliver address list to given host *
1297 *************************************************/
1298
1299 /* If continue_hostname is not null, we get here only when continuing to
1300 deliver down an existing channel. The channel was passed as the standard
1301 input. TLS is never active on a passed channel; the previous process always
1302 closes it down before passing the connection on.
1303
1304 Otherwise, we have to make a connection to the remote host, and do the
1305 initial protocol exchange.
1306
1307 When running as an MUA wrapper, if the sender or any recipient is rejected,
1308 temporarily or permanently, we force failure for all recipients.
1309
1310 Arguments:
1311 addrlist chain of potential addresses to deliver; only those whose
1312 transport_return field is set to PENDING_DEFER are currently
1313 being processed; others should be skipped - they have either
1314 been delivered to an earlier host or IP address, or been
1315 failed by one of them.
1316 host host to deliver to
1317 host_af AF_INET or AF_INET6
1318 port default TCP/IP port to use, in host byte order
1319 interface interface to bind to, or NULL
1320 tblock transport instance block
1321 message_defer set TRUE if yield is OK, but all addresses were deferred
1322 because of a non-recipient, non-host failure, that is, a
1323 4xx response to MAIL FROM, DATA, or ".". This is a defer
1324 that is specific to the message.
1325 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1326 a second attempt after TLS initialization fails
1327
1328 Returns: OK - the connection was made and the delivery attempted;
1329 the result for each address is in its data block.
1330 DEFER - the connection could not be made, or something failed
1331 while setting up the SMTP session, or there was a
1332 non-message-specific error, such as a timeout.
1333 ERROR - a filter command is specified for this transport,
1334 and there was a problem setting it up; OR helo_data
1335 or add_headers or authenticated_sender is specified
1336 for this transport, and the string failed to expand
1337 */
1338
1339 static int
1340 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
1341 uschar *interface, transport_instance *tblock,
1342 BOOL *message_defer, BOOL suppress_tls)
1343 {
1344 address_item *addr;
1345 address_item *sync_addr;
1346 address_item *first_addr = addrlist;
1347 int yield = OK;
1348 int address_count;
1349 int save_errno;
1350 int rc;
1351 time_t start_delivery_time = time(NULL);
1352 smtp_transport_options_block *ob =
1353 (smtp_transport_options_block *)(tblock->options_block);
1354 BOOL lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
1355 BOOL smtps = strcmpic(ob->protocol, US"smtps") == 0;
1356 BOOL ok = FALSE;
1357 BOOL send_rset = TRUE;
1358 BOOL send_quit = TRUE;
1359 BOOL setting_up = TRUE;
1360 BOOL completed_address = FALSE;
1361 BOOL esmtp = TRUE;
1362 BOOL pending_MAIL;
1363 BOOL pass_message = FALSE;
1364 #ifndef DISABLE_PRDR
1365 BOOL prdr_offered = FALSE;
1366 BOOL prdr_active;
1367 #endif
1368 #ifdef EXPERIMENTAL_INTERNATIONAL
1369 BOOL utf8_offered = FALSE;
1370 #endif
1371 BOOL dsn_all_lasthop = TRUE;
1372 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1373 BOOL dane = FALSE;
1374 BOOL dane_required;
1375 dns_answer tlsa_dnsa;
1376 #endif
1377 smtp_inblock inblock;
1378 smtp_outblock outblock;
1379 int max_rcpt = tblock->max_addresses;
1380 uschar *igquotstr = US"";
1381
1382 uschar *helo_data = NULL;
1383
1384 uschar *message = NULL;
1385 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
1386 uschar *p;
1387 uschar buffer[4096];
1388 uschar inbuffer[4096];
1389 uschar outbuffer[4096];
1390 address_item * current_address;
1391
1392 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
1393
1394 *message_defer = FALSE;
1395 smtp_command = US"initial connection";
1396 if (max_rcpt == 0) max_rcpt = 999999;
1397
1398 /* Set up the buffer for reading SMTP response packets. */
1399
1400 inblock.buffer = inbuffer;
1401 inblock.buffersize = sizeof(inbuffer);
1402 inblock.ptr = inbuffer;
1403 inblock.ptrend = inbuffer;
1404
1405 /* Set up the buffer for holding SMTP commands while pipelining */
1406
1407 outblock.buffer = outbuffer;
1408 outblock.buffersize = sizeof(outbuffer);
1409 outblock.ptr = outbuffer;
1410 outblock.cmd_count = 0;
1411 outblock.authenticating = FALSE;
1412
1413 /* Reset the parameters of a TLS session. */
1414
1415 tls_out.bits = 0;
1416 tls_out.cipher = NULL; /* the one we may use for this transport */
1417 tls_out.ourcert = NULL;
1418 tls_out.peercert = NULL;
1419 tls_out.peerdn = NULL;
1420 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1421 tls_out.sni = NULL;
1422 #endif
1423 tls_out.ocsp = OCSP_NOT_REQ;
1424
1425 /* Flip the legacy TLS-related variables over to the outbound set in case
1426 they're used in the context of the transport. Don't bother resetting
1427 afterward as we're in a subprocess. */
1428
1429 tls_modify_variables(&tls_out);
1430
1431 #ifndef SUPPORT_TLS
1432 if (smtps)
1433 {
1434 set_errno(addrlist, ERRNO_TLSFAILURE, US"TLS support not available",
1435 DEFER, FALSE, NULL);
1436 return ERROR;
1437 }
1438 #endif
1439
1440 /* Make a connection to the host if this isn't a continued delivery, and handle
1441 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
1442 specially so they can be identified for retries. */
1443
1444 if (continue_hostname == NULL)
1445 {
1446 /* This puts port into host->port */
1447 inblock.sock = outblock.sock =
1448 smtp_connect(host, host_af, port, interface, ob->connect_timeout, tblock);
1449
1450 if (inblock.sock < 0)
1451 {
1452 set_errno(addrlist, (errno == ETIMEDOUT)? ERRNO_CONNECTTIMEOUT : errno,
1453 NULL, DEFER, FALSE, NULL);
1454 return DEFER;
1455 }
1456
1457 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1458 {
1459 tls_out.dane_verified = FALSE;
1460 tls_out.tlsa_usage = 0;
1461
1462 dane_required = verify_check_given_host(&ob->hosts_require_dane, host) == OK;
1463
1464 if (host->dnssec == DS_YES)
1465 {
1466 if( ( dane_required
1467 || verify_check_given_host(&ob->hosts_try_dane, host) == OK
1468 )
1469 && (rc = tlsa_lookup(host, &tlsa_dnsa, dane_required, &dane)) != OK
1470 )
1471 return rc;
1472 }
1473 else if (dane_required)
1474 {
1475 log_write(0, LOG_MAIN, "DANE error: %s lookup not DNSSEC", host->name);
1476 return FAIL;
1477 }
1478
1479 if (dane)
1480 ob->tls_tempfail_tryclear = FALSE;
1481 }
1482 #endif /*DANE*/
1483
1484 /* Expand the greeting message while waiting for the initial response. (Makes
1485 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1486 delayed till here so that $sending_interface and $sending_port are set. */
1487
1488 helo_data = expand_string(ob->helo_data);
1489 #ifdef EXPERIMENTAL_INTERNATIONAL
1490 if (helo_data)
1491 {
1492 uschar * errstr = NULL;
1493 if ((helo_data = string_domain_utf8_to_alabel(helo_data, &errstr)), errstr)
1494 {
1495 errstr = string_sprintf("failed to expand helo_data: %s", errstr);
1496 set_errno(addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE, NULL);
1497 yield = DEFER;
1498 goto SEND_QUIT;
1499 }
1500 }
1501 #endif
1502
1503 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1504 is nevertheless a reasonably clean way of programming this kind of logic,
1505 where you want to escape on any error. */
1506
1507 if (!smtps)
1508 {
1509 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1510 ob->command_timeout)) goto RESPONSE_FAILED;
1511
1512 #ifdef EXPERIMENTAL_EVENT
1513 {
1514 uschar * s;
1515 lookup_dnssec_authenticated = host->dnssec==DS_YES ? US"yes"
1516 : host->dnssec==DS_NO ? US"no" : NULL;
1517 s = event_raise(tblock->event_action, US"smtp:connect", buffer);
1518 if (s)
1519 {
1520 set_errno(addrlist, ERRNO_EXPANDFAIL,
1521 string_sprintf("deferred by smtp:connect event expansion: %s", s),
1522 DEFER, FALSE, NULL);
1523 yield = DEFER;
1524 goto SEND_QUIT;
1525 }
1526 }
1527 #endif
1528
1529 /* Now check if the helo_data expansion went well, and sign off cleanly if
1530 it didn't. */
1531
1532 if (helo_data == NULL)
1533 {
1534 uschar *message = string_sprintf("failed to expand helo_data: %s",
1535 expand_string_message);
1536 set_errno(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, NULL);
1537 yield = DEFER;
1538 goto SEND_QUIT;
1539 }
1540 }
1541
1542 /** Debugging without sending a message
1543 addrlist->transport_return = DEFER;
1544 goto SEND_QUIT;
1545 **/
1546
1547 /* Errors that occur after this point follow an SMTP command, which is
1548 left in big_buffer by smtp_write_command() for use in error messages. */
1549
1550 smtp_command = big_buffer;
1551
1552 /* Tell the remote who we are...
1553
1554 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1555 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1556 greeting is of this form. The assumption was that the far end supports it
1557 properly... but experience shows that there are some that give 5xx responses,
1558 even though the banner includes "ESMTP" (there's a bloody-minded one that
1559 says "ESMTP not spoken here"). Cope with that case.
1560
1561 September 2000: Time has passed, and it seems reasonable now to always send
1562 EHLO at the start. It is also convenient to make the change while installing
1563 the TLS stuff.
1564
1565 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1566 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1567 would be no way to send out the mails, so there is now a host list
1568 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1569 PIPELINING problem as well. Maybe it can also be useful to cure other
1570 problems with broken servers.
1571
1572 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1573 Then somebody tried it with a Microsoft mailer... It seems that all other
1574 mailers use upper case for some reason (the RFC is quite clear about case
1575 independence) so, for peace of mind, I gave in. */
1576
1577 esmtp = verify_check_given_host(&ob->hosts_avoid_esmtp, host) != OK;
1578
1579 /* Alas; be careful, since this goto is not an error-out, so conceivably
1580 we might set data between here and the target which we assume to exist
1581 and be usable. I can see this coming back to bite us. */
1582 #ifdef SUPPORT_TLS
1583 if (smtps)
1584 {
1585 tls_offered = TRUE;
1586 suppress_tls = FALSE;
1587 ob->tls_tempfail_tryclear = FALSE;
1588 smtp_command = US"SSL-on-connect";
1589 goto TLS_NEGOTIATE;
1590 }
1591 #endif
1592
1593 if (esmtp)
1594 {
1595 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1596 lmtp? "LHLO" : "EHLO", helo_data) < 0)
1597 goto SEND_FAILED;
1598 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1599 ob->command_timeout))
1600 {
1601 if (errno != 0 || buffer[0] == 0 || lmtp) goto RESPONSE_FAILED;
1602 esmtp = FALSE;
1603 }
1604 }
1605 else
1606 {
1607 DEBUG(D_transport)
1608 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1609 }
1610
1611 if (!esmtp)
1612 {
1613 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1614 goto SEND_FAILED;
1615 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1616 ob->command_timeout)) goto RESPONSE_FAILED;
1617 }
1618
1619 /* Set IGNOREQUOTA if the response to LHLO specifies support and the
1620 lmtp_ignore_quota option was set. */
1621
1622 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1623 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1624 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1625
1626 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1627
1628 #ifdef SUPPORT_TLS
1629 tls_offered = esmtp &&
1630 pcre_exec(regex_STARTTLS, NULL, CS buffer, Ustrlen(buffer), 0,
1631 PCRE_EOPT, NULL, 0) >= 0;
1632 #endif
1633
1634 #ifndef DISABLE_PRDR
1635 prdr_offered = esmtp
1636 && pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(buffer), 0,
1637 PCRE_EOPT, NULL, 0) >= 0
1638 && verify_check_given_host(&ob->hosts_try_prdr, host) == OK;
1639
1640 if (prdr_offered)
1641 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1642 #endif
1643
1644 #ifdef EXPERIMENTAL_INTERNATIONAL
1645 utf8_offered = esmtp
1646 && addrlist->prop.utf8
1647 && pcre_exec(regex_UTF8, NULL, CS buffer, Ustrlen(buffer), 0,
1648 PCRE_EOPT, NULL, 0) >= 0;
1649 #endif
1650 }
1651
1652 /* For continuing deliveries down the same channel, the socket is the standard
1653 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1654 below). Set up the pointer to where subsequent commands will be left, for
1655 error messages. Note that smtp_use_size and smtp_use_pipelining will have been
1656 set from the command line if they were set in the process that passed the
1657 connection on. */
1658
1659 else
1660 {
1661 inblock.sock = outblock.sock = fileno(stdin);
1662 smtp_command = big_buffer;
1663 host->port = port; /* Record the port that was used */
1664 }
1665
1666 /* If TLS is available on this connection, whether continued or not, attempt to
1667 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1668 send another EHLO - the server may give a different answer in secure mode. We
1669 use a separate buffer for reading the response to STARTTLS so that if it is
1670 negative, the original EHLO data is available for subsequent analysis, should
1671 the client not be required to use TLS. If the response is bad, copy the buffer
1672 for error analysis. */
1673
1674 #ifdef SUPPORT_TLS
1675 if ( tls_offered
1676 && !suppress_tls
1677 && verify_check_given_host(&ob->hosts_avoid_tls, host) != OK)
1678 {
1679 uschar buffer2[4096];
1680 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1681 goto SEND_FAILED;
1682
1683 /* If there is an I/O error, transmission of this message is deferred. If
1684 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1685 false, we also defer. However, if there is a temporary rejection of STARTTLS
1686 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1687 STARTTLS, we carry on. This means we will try to send the message in clear,
1688 unless the host is in hosts_require_tls (tested below). */
1689
1690 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1691 ob->command_timeout))
1692 {
1693 if (errno != 0 || buffer2[0] == 0 ||
1694 (buffer2[0] == '4' && !ob->tls_tempfail_tryclear))
1695 {
1696 Ustrncpy(buffer, buffer2, sizeof(buffer));
1697 goto RESPONSE_FAILED;
1698 }
1699 }
1700
1701 /* STARTTLS accepted: try to negotiate a TLS session. */
1702
1703 else
1704 TLS_NEGOTIATE:
1705 {
1706 int rc = tls_client_start(inblock.sock, host, addrlist, tblock
1707 # ifdef EXPERIMENTAL_DANE
1708 , dane ? &tlsa_dnsa : NULL
1709 # endif
1710 );
1711
1712 /* TLS negotiation failed; give an error. From outside, this function may
1713 be called again to try in clear on a new connection, if the options permit
1714 it for this host. */
1715
1716 if (rc != OK)
1717 {
1718 # ifdef EXPERIMENTAL_DANE
1719 if (rc == DEFER && dane && !dane_required)
1720 {
1721 log_write(0, LOG_MAIN, "DANE attempt failed;"
1722 " trying CA-root TLS to %s [%s] (not in hosts_require_dane)",
1723 host->name, host->address);
1724 dane = FALSE;
1725 goto TLS_NEGOTIATE;
1726 }
1727 # endif
1728
1729 save_errno = ERRNO_TLSFAILURE;
1730 message = US"failure while setting up TLS session";
1731 send_quit = FALSE;
1732 goto TLS_FAILED;
1733 }
1734
1735 /* TLS session is set up */
1736
1737 for (addr = addrlist; addr != NULL; addr = addr->next)
1738 if (addr->transport_return == PENDING_DEFER)
1739 {
1740 addr->cipher = tls_out.cipher;
1741 addr->ourcert = tls_out.ourcert;
1742 addr->peercert = tls_out.peercert;
1743 addr->peerdn = tls_out.peerdn;
1744 addr->ocsp = tls_out.ocsp;
1745 }
1746 }
1747 }
1748
1749 /* if smtps, we'll have smtp_command set to something else; always safe to
1750 reset it here. */
1751 smtp_command = big_buffer;
1752
1753 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1754 helo_data is null, we are dealing with a connection that was passed from
1755 another process, and so we won't have expanded helo_data above. We have to
1756 expand it here. $sending_ip_address and $sending_port are set up right at the
1757 start of the Exim process (in exim.c). */
1758
1759 if (tls_out.active >= 0)
1760 {
1761 char *greeting_cmd;
1762 if (helo_data == NULL)
1763 {
1764 helo_data = expand_string(ob->helo_data);
1765 if (helo_data == NULL)
1766 {
1767 uschar *message = string_sprintf("failed to expand helo_data: %s",
1768 expand_string_message);
1769 set_errno(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, NULL);
1770 yield = DEFER;
1771 goto SEND_QUIT;
1772 }
1773 }
1774
1775 /* For SMTPS we need to wait for the initial OK response. */
1776 if (smtps)
1777 {
1778 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1779 ob->command_timeout)) goto RESPONSE_FAILED;
1780 }
1781
1782 if (esmtp)
1783 greeting_cmd = "EHLO";
1784 else
1785 {
1786 greeting_cmd = "HELO";
1787 DEBUG(D_transport)
1788 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1789 }
1790
1791 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1792 lmtp? "LHLO" : greeting_cmd, helo_data) < 0)
1793 goto SEND_FAILED;
1794 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1795 ob->command_timeout))
1796 goto RESPONSE_FAILED;
1797 }
1798
1799 /* If the host is required to use a secure channel, ensure that we
1800 have one. */
1801
1802 else if (
1803 # ifdef EXPERIMENTAL_DANE
1804 dane ||
1805 # endif
1806 verify_check_given_host(&ob->hosts_require_tls, host) == OK
1807 )
1808 {
1809 save_errno = ERRNO_TLSREQUIRED;
1810 message = string_sprintf("a TLS session is required, but %s",
1811 tls_offered? "an attempt to start TLS failed" :
1812 "the server did not offer TLS support");
1813 goto TLS_FAILED;
1814 }
1815 #endif /*SUPPORT_TLS*/
1816
1817 /* If TLS is active, we have just started it up and re-done the EHLO command,
1818 so its response needs to be analyzed. If TLS is not active and this is a
1819 continued session down a previously-used socket, we haven't just done EHLO, so
1820 we skip this. */
1821
1822 if (continue_hostname == NULL
1823 #ifdef SUPPORT_TLS
1824 || tls_out.active >= 0
1825 #endif
1826 )
1827 {
1828 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
1829 lmtp_ignore_quota option was set. */
1830
1831 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1832 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1833 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1834
1835 /* If the response to EHLO specified support for the SIZE parameter, note
1836 this, provided size_addition is non-negative. */
1837
1838 smtp_use_size = esmtp && ob->size_addition >= 0 &&
1839 pcre_exec(regex_SIZE, NULL, CS buffer, Ustrlen(CS buffer), 0,
1840 PCRE_EOPT, NULL, 0) >= 0;
1841
1842 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
1843 the current host, esmtp will be false, so PIPELINING can never be used. If
1844 the current host matches hosts_avoid_pipelining, don't do it. */
1845
1846 smtp_use_pipelining = esmtp
1847 && verify_check_given_host(&ob->hosts_avoid_pipelining, host) != OK
1848 && pcre_exec(regex_PIPELINING, NULL, CS buffer, Ustrlen(CS buffer), 0,
1849 PCRE_EOPT, NULL, 0) >= 0;
1850
1851 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
1852 smtp_use_pipelining? "" : "not ");
1853
1854 #ifndef DISABLE_PRDR
1855 prdr_offered = esmtp
1856 && pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(CS buffer), 0,
1857 PCRE_EOPT, NULL, 0) >= 0
1858 && verify_check_given_host(&ob->hosts_try_prdr, host) == OK;
1859
1860 if (prdr_offered)
1861 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1862 #endif
1863
1864 #ifdef EXPERIMENTAL_INTERNATIONAL
1865 utf8_offered = esmtp
1866 && addrlist->prop.utf8
1867 && pcre_exec(regex_UTF8, NULL, CS buffer, Ustrlen(buffer), 0,
1868 PCRE_EOPT, NULL, 0) >= 0;
1869 #endif
1870
1871 /* Note if the server supports DSN */
1872 smtp_use_dsn = esmtp
1873 && pcre_exec(regex_DSN, NULL, CS buffer, Ustrlen(CS buffer), 0,
1874 PCRE_EOPT, NULL, 0) >= 0;
1875 DEBUG(D_transport) debug_printf("use_dsn=%d\n", smtp_use_dsn);
1876
1877 /* Note if the response to EHLO specifies support for the AUTH extension.
1878 If it has, check that this host is one we want to authenticate to, and do
1879 the business. The host name and address must be available when the
1880 authenticator's client driver is running. */
1881
1882 switch (yield = smtp_auth(buffer, sizeof(buffer), addrlist, host,
1883 ob, esmtp, &inblock, &outblock))
1884 {
1885 default: goto SEND_QUIT;
1886 case OK: break;
1887 case FAIL_SEND: goto SEND_FAILED;
1888 case FAIL: goto RESPONSE_FAILED;
1889 }
1890 }
1891
1892 /* The setting up of the SMTP call is now complete. Any subsequent errors are
1893 message-specific. */
1894
1895 setting_up = FALSE;
1896
1897 #ifdef EXPERIMENTAL_INTERNATIONAL
1898 /* If this is an international message we need the host to speak SMTPUTF8 */
1899 if (addrlist->prop.utf8 && !utf8_offered)
1900 {
1901 errno = ERRNO_UTF8_FWD;
1902 goto RESPONSE_FAILED;
1903 }
1904 #endif
1905
1906 /* If there is a filter command specified for this transport, we can now
1907 set it up. This cannot be done until the identify of the host is known. */
1908
1909 if (tblock->filter_command != NULL)
1910 {
1911 BOOL rc;
1912 uschar buffer[64];
1913 sprintf(CS buffer, "%.50s transport", tblock->name);
1914 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
1915 TRUE, DEFER, addrlist, buffer, NULL);
1916 transport_filter_timeout = tblock->filter_timeout;
1917
1918 /* On failure, copy the error to all addresses, abandon the SMTP call, and
1919 yield ERROR. */
1920
1921 if (!rc)
1922 {
1923 set_errno(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
1924 FALSE, NULL);
1925 yield = ERROR;
1926 goto SEND_QUIT;
1927 }
1928 }
1929
1930
1931 /* For messages that have more than the maximum number of envelope recipients,
1932 we want to send several transactions down the same SMTP connection. (See
1933 comments in deliver.c as to how this reconciles, heuristically, with
1934 remote_max_parallel.) This optimization was added to Exim after the following
1935 code was already working. The simplest way to put it in without disturbing the
1936 code was to use a goto to jump back to this point when there is another
1937 transaction to handle. */
1938
1939 SEND_MESSAGE:
1940 sync_addr = first_addr;
1941 address_count = 0;
1942 ok = FALSE;
1943 send_rset = TRUE;
1944 completed_address = FALSE;
1945
1946
1947 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
1948 qualification, send it, adding something to the message size to allow for
1949 imprecision and things that get added en route. Exim keeps the number of lines
1950 in a message, so we can give an accurate value for the original message, but we
1951 need some additional to handle added headers. (Double "." characters don't get
1952 included in the count.) */
1953
1954 p = buffer;
1955 *p = 0;
1956
1957 if (smtp_use_size)
1958 {
1959 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
1960 while (*p) p++;
1961 }
1962
1963 #ifndef DISABLE_PRDR
1964 prdr_active = FALSE;
1965 if (prdr_offered)
1966 {
1967 for (addr = first_addr; addr; addr = addr->next)
1968 if (addr->transport_return == PENDING_DEFER)
1969 {
1970 for (addr = addr->next; addr; addr = addr->next)
1971 if (addr->transport_return == PENDING_DEFER)
1972 { /* at least two recipients to send */
1973 prdr_active = TRUE;
1974 sprintf(CS p, " PRDR"); p += 5;
1975 break;
1976 }
1977 break;
1978 }
1979 }
1980 #endif
1981
1982 #ifdef EXPERIMENTAL_INTERNATIONAL
1983 if (addrlist->prop.utf8)
1984 sprintf(CS p, " SMTPUTF8"), p += 9;
1985 #endif
1986
1987 /* check if all addresses have lasthop flag */
1988 /* do not send RET and ENVID if true */
1989 for (dsn_all_lasthop = TRUE, addr = first_addr;
1990 address_count < max_rcpt && addr != NULL;
1991 addr = addr->next)
1992 if ((addr->dsn_flags & rf_dsnlasthop) != 1)
1993 {
1994 dsn_all_lasthop = FALSE;
1995 break;
1996 }
1997
1998 /* Add any DSN flags to the mail command */
1999
2000 if (smtp_use_dsn && !dsn_all_lasthop)
2001 {
2002 if (dsn_ret == dsn_ret_hdrs)
2003 {
2004 Ustrcpy(p, " RET=HDRS");
2005 while (*p) p++;
2006 }
2007 else if (dsn_ret == dsn_ret_full)
2008 {
2009 Ustrcpy(p, " RET=FULL");
2010 while (*p) p++;
2011 }
2012 if (dsn_envid != NULL)
2013 {
2014 string_format(p, sizeof(buffer) - (p-buffer), " ENVID=%s", dsn_envid);
2015 while (*p) p++;
2016 }
2017 }
2018
2019 /* If an authenticated_sender override has been specified for this transport
2020 instance, expand it. If the expansion is forced to fail, and there was already
2021 an authenticated_sender for this message, the original value will be used.
2022 Other expansion failures are serious. An empty result is ignored, but there is
2023 otherwise no check - this feature is expected to be used with LMTP and other
2024 cases where non-standard addresses (e.g. without domains) might be required. */
2025
2026 if (smtp_mail_auth_str(p, sizeof(buffer) - (p-buffer), addrlist, ob))
2027 {
2028 yield = ERROR;
2029 goto SEND_QUIT;
2030 }
2031
2032 /* From here until we send the DATA command, we can make use of PIPELINING
2033 if the server host supports it. The code has to be able to check the responses
2034 at any point, for when the buffer fills up, so we write it totally generally.
2035 When PIPELINING is off, each command written reports that it has flushed the
2036 buffer. */
2037
2038 pending_MAIL = TRUE; /* The block starts with MAIL */
2039
2040 rc = smtp_write_command(&outblock, smtp_use_pipelining,
2041 "MAIL FROM:<%s>%s\r\n", return_path, buffer);
2042 mail_command = string_copy(big_buffer); /* Save for later error message */
2043
2044 switch(rc)
2045 {
2046 case -1: /* Transmission error */
2047 goto SEND_FAILED;
2048
2049 case +1: /* Block was sent */
2050 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2051 ob->command_timeout))
2052 {
2053 if (errno == 0 && buffer[0] == '4')
2054 {
2055 errno = ERRNO_MAIL4XX;
2056 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2057 }
2058 goto RESPONSE_FAILED;
2059 }
2060 pending_MAIL = FALSE;
2061 break;
2062 }
2063
2064 /* Pass over all the relevant recipient addresses for this host, which are the
2065 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
2066 several before we have to read the responses for those seen so far. This
2067 checking is done by a subroutine because it also needs to be done at the end.
2068 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
2069 the next one if not all are sent.
2070
2071 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
2072 last address because we want to abort if any recipients have any kind of
2073 problem, temporary or permanent. We know that all recipient addresses will have
2074 the PENDING_DEFER status, because only one attempt is ever made, and we know
2075 that max_rcpt will be large, so all addresses will be done at once. */
2076
2077 for (addr = first_addr;
2078 address_count < max_rcpt && addr != NULL;
2079 addr = addr->next)
2080 {
2081 int count;
2082 BOOL no_flush;
2083
2084 addr->dsn_aware = smtp_use_dsn ? dsn_support_yes : dsn_support_no;
2085
2086 if (addr->transport_return != PENDING_DEFER) continue;
2087
2088 address_count++;
2089 no_flush = smtp_use_pipelining && (!mua_wrapper || addr->next != NULL);
2090
2091 /* Add any DSN flags to the rcpt command and add to the sent string */
2092
2093 p = buffer;
2094 *p = 0;
2095
2096 if (smtp_use_dsn && (addr->dsn_flags & rf_dsnlasthop) != 1)
2097 {
2098 if ((addr->dsn_flags & rf_dsnflags) != 0)
2099 {
2100 int i;
2101 BOOL first = TRUE;
2102 Ustrcpy(p, " NOTIFY=");
2103 while (*p) p++;
2104 for (i = 0; i < 4; i++)
2105 if ((addr->dsn_flags & rf_list[i]) != 0)
2106 {
2107 if (!first) *p++ = ',';
2108 first = FALSE;
2109 Ustrcpy(p, rf_names[i]);
2110 while (*p) p++;
2111 }
2112 }
2113
2114 if (addr->dsn_orcpt != NULL)
2115 {
2116 string_format(p, sizeof(buffer) - (p-buffer), " ORCPT=%s",
2117 addr->dsn_orcpt);
2118 while (*p) p++;
2119 }
2120 }
2121
2122 /* Now send the RCPT command, and process outstanding responses when
2123 necessary. After a timeout on RCPT, we just end the function, leaving the
2124 yield as OK, because this error can often mean that there is a problem with
2125 just one address, so we don't want to delay the host. */
2126
2127 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s%s\r\n",
2128 transport_rcpt_address(addr, tblock->rcpt_include_affixes), igquotstr, buffer);
2129
2130 if (count < 0) goto SEND_FAILED;
2131 if (count > 0)
2132 {
2133 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
2134 &sync_addr, host, count, ob->address_retry_include_sender,
2135 pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
2136 sizeof(buffer)))
2137 {
2138 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2139 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2140 break;
2141
2142 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2143 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2144 case 0: /* No 2xx or 5xx, but no probs */
2145 break;
2146
2147 case -1: goto END_OFF; /* Timeout on RCPT */
2148 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
2149 }
2150 pending_MAIL = FALSE; /* Dealt with MAIL */
2151 }
2152 } /* Loop for next address */
2153
2154 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
2155 permanently or temporarily. We should have flushed and synced after the last
2156 RCPT. */
2157
2158 if (mua_wrapper)
2159 {
2160 address_item *badaddr;
2161 for (badaddr = first_addr; badaddr; badaddr = badaddr->next)
2162 if (badaddr->transport_return != PENDING_OK)
2163 {
2164 /*XXX could we find a better errno than 0 here? */
2165 set_errno(addrlist, 0, badaddr->message, FAIL,
2166 testflag(badaddr, af_pass_message), NULL);
2167 ok = FALSE;
2168 break;
2169 }
2170 }
2171
2172 /* If ok is TRUE, we know we have got at least one good recipient, and must now
2173 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
2174 have a good recipient buffered up if we are pipelining. We don't want to waste
2175 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
2176 are pipelining. The responses are all handled by sync_responses(). */
2177
2178 if (ok || (smtp_use_pipelining && !mua_wrapper))
2179 {
2180 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
2181 if (count < 0) goto SEND_FAILED;
2182 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
2183 host, count, ob->address_retry_include_sender, pending_MAIL,
2184 ok? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
2185 {
2186 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2187 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2188 break;
2189
2190 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2191 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2192 case 0: break; /* No 2xx or 5xx, but no probs */
2193
2194 case -1: goto END_OFF; /* Timeout on RCPT */
2195 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2196 }
2197 }
2198
2199 /* Save the first address of the next batch. */
2200
2201 first_addr = addr;
2202
2203 /* If there were no good recipients (but otherwise there have been no
2204 problems), just set ok TRUE, since we have handled address-specific errors
2205 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
2206 for handling the SMTP dot-handling protocol, flagging to apply to headers as
2207 well as body. Set the appropriate timeout value to be used for each chunk.
2208 (Haven't been able to make it work using select() for writing yet.) */
2209
2210 if (!ok) ok = TRUE; else
2211 {
2212 sigalrm_seen = FALSE;
2213 transport_write_timeout = ob->data_timeout;
2214 smtp_command = US"sending data block"; /* For error messages */
2215 DEBUG(D_transport|D_v)
2216 debug_printf(" SMTP>> writing message and terminating \".\"\n");
2217 transport_count = 0;
2218
2219 #ifndef DISABLE_DKIM
2220 ok = dkim_transport_write_message(addrlist, inblock.sock,
2221 topt_use_crlf | topt_end_dot | topt_escape_headers |
2222 (tblock->body_only? topt_no_headers : 0) |
2223 (tblock->headers_only? topt_no_body : 0) |
2224 (tblock->return_path_add? topt_add_return_path : 0) |
2225 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
2226 (tblock->envelope_to_add? topt_add_envelope_to : 0),
2227 0, /* No size limit */
2228 tblock->add_headers, tblock->remove_headers,
2229 US".", US"..", /* Escaping strings */
2230 tblock->rewrite_rules, tblock->rewrite_existflags,
2231 ob->dkim_private_key, ob->dkim_domain, ob->dkim_selector,
2232 ob->dkim_canon, ob->dkim_strict, ob->dkim_sign_headers
2233 );
2234 #else
2235 ok = transport_write_message(addrlist, inblock.sock,
2236 topt_use_crlf | topt_end_dot | topt_escape_headers |
2237 (tblock->body_only? topt_no_headers : 0) |
2238 (tblock->headers_only? topt_no_body : 0) |
2239 (tblock->return_path_add? topt_add_return_path : 0) |
2240 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
2241 (tblock->envelope_to_add? topt_add_envelope_to : 0),
2242 0, /* No size limit */
2243 tblock->add_headers, tblock->remove_headers,
2244 US".", US"..", /* Escaping strings */
2245 tblock->rewrite_rules, tblock->rewrite_existflags);
2246 #endif
2247
2248 /* transport_write_message() uses write() because it is called from other
2249 places to write to non-sockets. This means that under some OS (e.g. Solaris)
2250 it can exit with "Broken pipe" as its error. This really means that the
2251 socket got closed at the far end. */
2252
2253 transport_write_timeout = 0; /* for subsequent transports */
2254
2255 /* Failure can either be some kind of I/O disaster (including timeout),
2256 or the failure of a transport filter or the expansion of added headers. */
2257
2258 if (!ok)
2259 {
2260 buffer[0] = 0; /* There hasn't been a response */
2261 goto RESPONSE_FAILED;
2262 }
2263
2264 /* We used to send the terminating "." explicitly here, but because of
2265 buffering effects at both ends of TCP/IP connections, you don't gain
2266 anything by keeping it separate, so it might as well go in the final
2267 data buffer for efficiency. This is now done by setting the topt_end_dot
2268 flag above. */
2269
2270 smtp_command = US"end of data";
2271
2272 #ifndef DISABLE_PRDR
2273 /* For PRDR we optionally get a partial-responses warning
2274 * followed by the individual responses, before going on with
2275 * the overall response. If we don't get the warning then deal
2276 * with per non-PRDR. */
2277 if(prdr_active)
2278 {
2279 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '3',
2280 ob->final_timeout);
2281 if (!ok && errno == 0)
2282 switch(buffer[0])
2283 {
2284 case '2': prdr_active = FALSE;
2285 ok = TRUE;
2286 break;
2287 case '4': errno = ERRNO_DATA4XX;
2288 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2289 break;
2290 }
2291 }
2292 else
2293 #endif
2294
2295 /* For non-PRDR SMTP, we now read a single response that applies to the
2296 whole message. If it is OK, then all the addresses have been delivered. */
2297
2298 if (!lmtp)
2299 {
2300 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2301 ob->final_timeout);
2302 if (!ok && errno == 0 && buffer[0] == '4')
2303 {
2304 errno = ERRNO_DATA4XX;
2305 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2306 }
2307 }
2308
2309 /* For LMTP, we get back a response for every RCPT command that we sent;
2310 some may be accepted and some rejected. For those that get a response, their
2311 status is fixed; any that are accepted have been handed over, even if later
2312 responses crash - at least, that's how I read RFC 2033.
2313
2314 If all went well, mark the recipient addresses as completed, record which
2315 host/IPaddress they were delivered to, and cut out RSET when sending another
2316 message down the same channel. Write the completed addresses to the journal
2317 now so that they are recorded in case there is a crash of hardware or
2318 software before the spool gets updated. Also record the final SMTP
2319 confirmation if needed (for SMTP only). */
2320
2321 if (ok)
2322 {
2323 int flag = '=';
2324 int delivery_time = (int)(time(NULL) - start_delivery_time);
2325 int len;
2326 uschar *conf = NULL;
2327 send_rset = FALSE;
2328
2329 /* Set up confirmation if needed - applies only to SMTP */
2330
2331 if (
2332 #ifndef EXPERIMENTAL_EVENT
2333 (log_extra_selector & LX_smtp_confirmation) != 0 &&
2334 #endif
2335 !lmtp
2336 )
2337 {
2338 const uschar *s = string_printing(buffer);
2339 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
2340 conf = (s == buffer)? (uschar *)string_copy(s) : US s;
2341 }
2342
2343 /* Process all transported addresses - for LMTP or PRDR, read a status for
2344 each one. */
2345
2346 for (addr = addrlist; addr != first_addr; addr = addr->next)
2347 {
2348 if (addr->transport_return != PENDING_OK) continue;
2349
2350 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
2351 remaining addresses. Otherwise, it's a return code for just the one
2352 address. For temporary errors, add a retry item for the address so that
2353 it doesn't get tried again too soon. */
2354
2355 #ifndef DISABLE_PRDR
2356 if (lmtp || prdr_active)
2357 #else
2358 if (lmtp)
2359 #endif
2360 {
2361 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2362 ob->final_timeout))
2363 {
2364 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
2365 addr->message = string_sprintf(
2366 #ifndef DISABLE_PRDR
2367 "%s error after %s: %s", prdr_active ? "PRDR":"LMTP",
2368 #else
2369 "LMTP error after %s: %s",
2370 #endif
2371 big_buffer, string_printing(buffer));
2372 setflag(addr, af_pass_message); /* Allow message to go to user */
2373 if (buffer[0] == '5')
2374 addr->transport_return = FAIL;
2375 else
2376 {
2377 errno = ERRNO_DATA4XX;
2378 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2379 addr->transport_return = DEFER;
2380 #ifndef DISABLE_PRDR
2381 if (!prdr_active)
2382 #endif
2383 retry_add_item(addr, addr->address_retry_key, 0);
2384 }
2385 continue;
2386 }
2387 completed_address = TRUE; /* NOW we can set this flag */
2388 if ((log_extra_selector & LX_smtp_confirmation) != 0)
2389 {
2390 const uschar *s = string_printing(buffer);
2391 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
2392 conf = (s == buffer)? (uschar *)string_copy(s) : US s;
2393 }
2394 }
2395
2396 /* SMTP, or success return from LMTP for this address. Pass back the
2397 actual host that was used. */
2398
2399 addr->transport_return = OK;
2400 addr->more_errno = delivery_time;
2401 addr->host_used = host;
2402 addr->special_action = flag;
2403 addr->message = conf;
2404 #ifndef DISABLE_PRDR
2405 if (prdr_active) addr->flags |= af_prdr_used;
2406 #endif
2407 flag = '-';
2408
2409 #ifndef DISABLE_PRDR
2410 if (!prdr_active)
2411 #endif
2412 {
2413 /* Update the journal. For homonymic addresses, use the base address plus
2414 the transport name. See lots of comments in deliver.c about the reasons
2415 for the complications when homonyms are involved. Just carry on after
2416 write error, as it may prove possible to update the spool file later. */
2417
2418 if (testflag(addr, af_homonym))
2419 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2420 else
2421 sprintf(CS buffer, "%.500s\n", addr->unique);
2422
2423 DEBUG(D_deliver) debug_printf("journalling %s", buffer);
2424 len = Ustrlen(CS buffer);
2425 if (write(journal_fd, buffer, len) != len)
2426 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2427 "%s: %s", buffer, strerror(errno));
2428 }
2429 }
2430
2431 #ifndef DISABLE_PRDR
2432 if (prdr_active)
2433 {
2434 /* PRDR - get the final, overall response. For any non-success
2435 upgrade all the address statuses. */
2436 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2437 ob->final_timeout);
2438 if (!ok)
2439 {
2440 if(errno == 0 && buffer[0] == '4')
2441 {
2442 errno = ERRNO_DATA4XX;
2443 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2444 }
2445 for (addr = addrlist; addr != first_addr; addr = addr->next)
2446 if (buffer[0] == '5' || addr->transport_return == OK)
2447 addr->transport_return = PENDING_OK; /* allow set_errno action */
2448 goto RESPONSE_FAILED;
2449 }
2450
2451 /* Update the journal, or setup retry. */
2452 for (addr = addrlist; addr != first_addr; addr = addr->next)
2453 if (addr->transport_return == OK)
2454 {
2455 if (testflag(addr, af_homonym))
2456 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2457 else
2458 sprintf(CS buffer, "%.500s\n", addr->unique);
2459
2460 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s", buffer);
2461 len = Ustrlen(CS buffer);
2462 if (write(journal_fd, buffer, len) != len)
2463 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2464 "%s: %s", buffer, strerror(errno));
2465 }
2466 else if (addr->transport_return == DEFER)
2467 retry_add_item(addr, addr->address_retry_key, -2);
2468 }
2469 #endif
2470
2471 /* Ensure the journal file is pushed out to disk. */
2472
2473 if (EXIMfsync(journal_fd) < 0)
2474 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
2475 strerror(errno));
2476 }
2477 }
2478
2479
2480 /* Handle general (not specific to one address) failures here. The value of ok
2481 is used to skip over this code on the falling through case. A timeout causes a
2482 deferral. Other errors may defer or fail according to the response code, and
2483 may set up a special errno value, e.g. after connection chopped, which is
2484 assumed if errno == 0 and there is no text in the buffer. If control reaches
2485 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
2486 the problem is not related to this specific message. */
2487
2488 if (!ok)
2489 {
2490 int code;
2491
2492 RESPONSE_FAILED:
2493 save_errno = errno;
2494 message = NULL;
2495 send_quit = check_response(host, &save_errno, addrlist->more_errno,
2496 buffer, &code, &message, &pass_message);
2497 goto FAILED;
2498
2499 SEND_FAILED:
2500 save_errno = errno;
2501 code = '4';
2502 message = US string_sprintf("send() to %s [%s] failed: %s",
2503 host->name, host->address, strerror(save_errno));
2504 send_quit = FALSE;
2505 goto FAILED;
2506
2507 /* This label is jumped to directly when a TLS negotiation has failed,
2508 or was not done for a host for which it is required. Values will be set
2509 in message and save_errno, and setting_up will always be true. Treat as
2510 a temporary error. */
2511
2512 #ifdef SUPPORT_TLS
2513 TLS_FAILED:
2514 code = '4';
2515 #endif
2516
2517 /* If the failure happened while setting up the call, see if the failure was
2518 a 5xx response (this will either be on connection, or following HELO - a 5xx
2519 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
2520 never going to accept them. For other errors during setting up (timeouts or
2521 whatever), defer all addresses, and yield DEFER, so that the host is not
2522 tried again for a while. */
2523
2524 FAILED:
2525 ok = FALSE; /* For when reached by GOTO */
2526
2527 if (setting_up)
2528 {
2529 if (code == '5')
2530 set_errno(addrlist, save_errno, message, FAIL, pass_message, host);
2531 else
2532 {
2533 set_errno(addrlist, save_errno, message, DEFER, pass_message, host);
2534 yield = DEFER;
2535 }
2536 }
2537
2538 /* We want to handle timeouts after MAIL or "." and loss of connection after
2539 "." specially. They can indicate a problem with the sender address or with
2540 the contents of the message rather than a real error on the connection. These
2541 cases are treated in the same way as a 4xx response. This next bit of code
2542 does the classification. */
2543
2544 else
2545 {
2546 BOOL message_error;
2547
2548 switch(save_errno)
2549 {
2550 #ifdef EXPERIMENTAL_INTERNATIONAL
2551 case ERRNO_UTF8_FWD:
2552 code = '5';
2553 /*FALLTHROUGH*/
2554 #endif
2555 case 0:
2556 case ERRNO_MAIL4XX:
2557 case ERRNO_DATA4XX:
2558 message_error = TRUE;
2559 break;
2560
2561 case ETIMEDOUT:
2562 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
2563 Ustrncmp(smtp_command,"end ",4) == 0;
2564 break;
2565
2566 case ERRNO_SMTPCLOSED:
2567 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
2568 break;
2569
2570 default:
2571 message_error = FALSE;
2572 break;
2573 }
2574
2575 /* Handle the cases that are treated as message errors. These are:
2576
2577 (a) negative response or timeout after MAIL
2578 (b) negative response after DATA
2579 (c) negative response or timeout or dropped connection after "."
2580 (d) utf8 support required and not offered
2581
2582 It won't be a negative response or timeout after RCPT, as that is dealt
2583 with separately above. The action in all cases is to set an appropriate
2584 error code for all the addresses, but to leave yield set to OK because the
2585 host itself has not failed. Of course, it might in practice have failed
2586 when we've had a timeout, but if so, we'll discover that at the next
2587 delivery attempt. For a temporary error, set the message_defer flag, and
2588 write to the logs for information if this is not the last host. The error
2589 for the last host will be logged as part of the address's log line. */
2590
2591 if (message_error)
2592 {
2593 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
2594 set_errno(addrlist, save_errno, message, (code == '5')? FAIL : DEFER,
2595 pass_message, host);
2596
2597 /* If there's an errno, the message contains just the identity of
2598 the host. */
2599
2600 if (code != '5') /* Anything other than 5 is treated as temporary */
2601 {
2602 if (save_errno > 0)
2603 message = US string_sprintf("%s: %s", message, strerror(save_errno));
2604 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
2605 msglog_line(host, message);
2606 *message_defer = TRUE;
2607 }
2608 }
2609
2610 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
2611 ".", or some other transportation error. We defer all addresses and yield
2612 DEFER, except for the case of failed add_headers expansion, or a transport
2613 filter failure, when the yield should be ERROR, to stop it trying other
2614 hosts. */
2615
2616 else
2617 {
2618 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
2619 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
2620 set_errno(addrlist, save_errno, message, DEFER, pass_message, host);
2621 }
2622 }
2623 }
2624
2625
2626 /* If all has gone well, send_quit will be set TRUE, implying we can end the
2627 SMTP session tidily. However, if there were too many addresses to send in one
2628 message (indicated by first_addr being non-NULL) we want to carry on with the
2629 rest of them. Also, it is desirable to send more than one message down the SMTP
2630 connection if there are several waiting, provided we haven't already sent so
2631 many as to hit the configured limit. The function transport_check_waiting looks
2632 for a waiting message and returns its id. Then transport_pass_socket tries to
2633 set up a continued delivery by passing the socket on to another process. The
2634 variable send_rset is FALSE if a message has just been successfully transfered.
2635
2636 If we are already sending down a continued channel, there may be further
2637 addresses not yet delivered that are aimed at the same host, but which have not
2638 been passed in this run of the transport. In this case, continue_more will be
2639 true, and all we should do is send RSET if necessary, and return, leaving the
2640 channel open.
2641
2642 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
2643 do not want to continue with other messages down the same channel, because that
2644 can lead to looping between two or more messages, all with the same,
2645 temporarily failing address(es). [The retry information isn't updated yet, so
2646 new processes keep on trying.] We probably also don't want to try more of this
2647 message's addresses either.
2648
2649 If we have started a TLS session, we have to end it before passing the
2650 connection to a new process. However, not all servers can handle this (Exim
2651 can), so we do not pass such a connection on if the host matches
2652 hosts_nopass_tls. */
2653
2654 DEBUG(D_transport)
2655 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
2656 "yield=%d first_address is %sNULL\n", ok, send_quit, send_rset,
2657 continue_more, yield, (first_addr == NULL)? "":"not ");
2658
2659 if (completed_address && ok && send_quit)
2660 {
2661 BOOL more;
2662 smtp_compare_t t_compare;
2663
2664 t_compare.tblock = tblock;
2665 t_compare.current_sender_address = sender_address;
2666
2667 if ( first_addr != NULL
2668 || continue_more
2669 || ( ( tls_out.active < 0
2670 || verify_check_given_host(&ob->hosts_nopass_tls, host) != OK
2671 )
2672 &&
2673 transport_check_waiting(tblock->name, host->name,
2674 tblock->connection_max_messages, new_message_id, &more,
2675 (oicf)smtp_are_same_identities, (void*)&t_compare)
2676 ) )
2677 {
2678 uschar *msg;
2679 BOOL pass_message;
2680
2681 if (send_rset)
2682 {
2683 if (! (ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
2684 {
2685 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
2686 host->address, strerror(save_errno));
2687 send_quit = FALSE;
2688 }
2689 else if (! (ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2690 ob->command_timeout)))
2691 {
2692 int code;
2693 send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
2694 &pass_message);
2695 if (!send_quit)
2696 {
2697 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
2698 host->name, host->address, msg);
2699 }
2700 }
2701 }
2702
2703 /* Either RSET was not needed, or it succeeded */
2704
2705 if (ok)
2706 {
2707 if (first_addr != NULL) /* More addresses still to be sent */
2708 { /* in this run of the transport */
2709 continue_sequence++; /* Causes * in logging */
2710 goto SEND_MESSAGE;
2711 }
2712 if (continue_more) return yield; /* More addresses for another run */
2713
2714 /* Pass the socket to a new Exim process. Before doing so, we must shut
2715 down TLS. Not all MTAs allow for the continuation of the SMTP session
2716 when TLS is shut down. We test for this by sending a new EHLO. If we
2717 don't get a good response, we don't attempt to pass the socket on. */
2718
2719 #ifdef SUPPORT_TLS
2720 if (tls_out.active >= 0)
2721 {
2722 tls_close(FALSE, TRUE);
2723 if (smtps)
2724 ok = FALSE;
2725 else
2726 ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
2727 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2728 ob->command_timeout);
2729 }
2730 #endif
2731
2732 /* If the socket is successfully passed, we musn't send QUIT (or
2733 indeed anything!) from here. */
2734
2735 if (ok && transport_pass_socket(tblock->name, host->name, host->address,
2736 new_message_id, inblock.sock))
2737 {
2738 send_quit = FALSE;
2739 }
2740 }
2741
2742 /* If RSET failed and there are addresses left, they get deferred. */
2743
2744 else set_errno(first_addr, errno, msg, DEFER, FALSE, host);
2745 }
2746 }
2747
2748 /* End off tidily with QUIT unless the connection has died or the socket has
2749 been passed to another process. There has been discussion on the net about what
2750 to do after sending QUIT. The wording of the RFC suggests that it is necessary
2751 to wait for a response, but on the other hand, there isn't anything one can do
2752 with an error response, other than log it. Exim used to do that. However,
2753 further discussion suggested that it is positively advantageous not to wait for
2754 the response, but to close the session immediately. This is supposed to move
2755 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
2756 load from the server. (Hosts that are both servers and clients may not see much
2757 difference, of course.) Further discussion indicated that this was safe to do
2758 on Unix systems which have decent implementations of TCP/IP that leave the
2759 connection around for a while (TIME_WAIT) after the application has gone away.
2760 This enables the response sent by the server to be properly ACKed rather than
2761 timed out, as can happen on broken TCP/IP implementations on other OS.
2762
2763 This change is being made on 31-Jul-98. After over a year of trouble-free
2764 operation, the old commented-out code was removed on 17-Sep-99. */
2765
2766 SEND_QUIT:
2767 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2768
2769 END_OFF:
2770
2771 #ifdef SUPPORT_TLS
2772 tls_close(FALSE, TRUE);
2773 #endif
2774
2775 /* Close the socket, and return the appropriate value, first setting
2776 works because the NULL setting is passed back to the calling process, and
2777 remote_max_parallel is forced to 1 when delivering over an existing connection,
2778
2779 If all went well and continue_more is set, we shouldn't actually get here if
2780 there are further addresses, as the return above will be taken. However,
2781 writing RSET might have failed, or there may be other addresses whose hosts are
2782 specified in the transports, and therefore not visible at top level, in which
2783 case continue_more won't get set. */
2784
2785 (void)close(inblock.sock);
2786
2787 #ifdef EXPERIMENTAL_EVENT
2788 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
2789 #endif
2790
2791 continue_transport = NULL;
2792 continue_hostname = NULL;
2793 return yield;
2794 }
2795
2796
2797
2798
2799 /*************************************************
2800 * Closedown entry point *
2801 *************************************************/
2802
2803 /* This function is called when exim is passed an open smtp channel
2804 from another incarnation, but the message which it has been asked
2805 to deliver no longer exists. The channel is on stdin.
2806
2807 We might do fancy things like looking for another message to send down
2808 the channel, but if the one we sought has gone, it has probably been
2809 delivered by some other process that itself will seek further messages,
2810 so just close down our connection.
2811
2812 Argument: pointer to the transport instance block
2813 Returns: nothing
2814 */
2815
2816 void
2817 smtp_transport_closedown(transport_instance *tblock)
2818 {
2819 smtp_transport_options_block *ob =
2820 (smtp_transport_options_block *)(tblock->options_block);
2821 smtp_inblock inblock;
2822 smtp_outblock outblock;
2823 uschar buffer[256];
2824 uschar inbuffer[4096];
2825 uschar outbuffer[16];
2826
2827 inblock.sock = fileno(stdin);
2828 inblock.buffer = inbuffer;
2829 inblock.buffersize = sizeof(inbuffer);
2830 inblock.ptr = inbuffer;
2831 inblock.ptrend = inbuffer;
2832
2833 outblock.sock = inblock.sock;
2834 outblock.buffersize = sizeof(outbuffer);
2835 outblock.buffer = outbuffer;
2836 outblock.ptr = outbuffer;
2837 outblock.cmd_count = 0;
2838 outblock.authenticating = FALSE;
2839
2840 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2841 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2842 ob->command_timeout);
2843 (void)close(inblock.sock);
2844 }
2845
2846
2847
2848 /*************************************************
2849 * Prepare addresses for delivery *
2850 *************************************************/
2851
2852 /* This function is called to flush out error settings from previous delivery
2853 attempts to other hosts. It also records whether we got here via an MX record
2854 or not in the more_errno field of the address. We are interested only in
2855 addresses that are still marked DEFER - others may have got delivered to a
2856 previously considered IP address. Set their status to PENDING_DEFER to indicate
2857 which ones are relevant this time.
2858
2859 Arguments:
2860 addrlist the list of addresses
2861 host the host we are delivering to
2862
2863 Returns: the first address for this delivery
2864 */
2865
2866 static address_item *
2867 prepare_addresses(address_item *addrlist, host_item *host)
2868 {
2869 address_item *first_addr = NULL;
2870 address_item *addr;
2871 for (addr = addrlist; addr != NULL; addr = addr->next)
2872 if (addr->transport_return == DEFER)
2873 {
2874 if (first_addr == NULL) first_addr = addr;
2875 addr->transport_return = PENDING_DEFER;
2876 addr->basic_errno = 0;
2877 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
2878 addr->message = NULL;
2879 #ifdef SUPPORT_TLS
2880 addr->cipher = NULL;
2881 addr->ourcert = NULL;
2882 addr->peercert = NULL;
2883 addr->peerdn = NULL;
2884 addr->ocsp = OCSP_NOT_REQ;
2885 #endif
2886 }
2887 return first_addr;
2888 }
2889
2890
2891
2892 /*************************************************
2893 * Main entry point *
2894 *************************************************/
2895
2896 /* See local README for interface details. As this is a remote transport, it is
2897 given a chain of addresses to be delivered in one connection, if possible. It
2898 always returns TRUE, indicating that each address has its own independent
2899 status set, except if there is a setting up problem, in which case it returns
2900 FALSE. */
2901
2902 BOOL
2903 smtp_transport_entry(
2904 transport_instance *tblock, /* data for this instantiation */
2905 address_item *addrlist) /* addresses we are working on */
2906 {
2907 int cutoff_retry;
2908 int port;
2909 int hosts_defer = 0;
2910 int hosts_fail = 0;
2911 int hosts_looked_up = 0;
2912 int hosts_retry = 0;
2913 int hosts_serial = 0;
2914 int hosts_total = 0;
2915 int total_hosts_tried = 0;
2916 address_item *addr;
2917 BOOL expired = TRUE;
2918 BOOL continuing = continue_hostname != NULL;
2919 uschar *expanded_hosts = NULL;
2920 uschar *pistring;
2921 uschar *tid = string_sprintf("%s transport", tblock->name);
2922 smtp_transport_options_block *ob =
2923 (smtp_transport_options_block *)(tblock->options_block);
2924 host_item *hostlist = addrlist->host_list;
2925 host_item *host = NULL;
2926
2927 DEBUG(D_transport)
2928 {
2929 debug_printf("%s transport entered\n", tblock->name);
2930 for (addr = addrlist; addr != NULL; addr = addr->next)
2931 debug_printf(" %s\n", addr->address);
2932 if (continuing) debug_printf("already connected to %s [%s]\n",
2933 continue_hostname, continue_host_address);
2934 }
2935
2936 /* Set the flag requesting that these hosts be added to the waiting
2937 database if the delivery fails temporarily or if we are running with
2938 queue_smtp or a 2-stage queue run. This gets unset for certain
2939 kinds of error, typically those that are specific to the message. */
2940
2941 update_waiting = TRUE;
2942
2943 /* If a host list is not defined for the addresses - they must all have the
2944 same one in order to be passed to a single transport - or if the transport has
2945 a host list with hosts_override set, use the host list supplied with the
2946 transport. It is an error for this not to exist. */
2947
2948 if (hostlist == NULL || (ob->hosts_override && ob->hosts != NULL))
2949 {
2950 if (ob->hosts == NULL)
2951 {
2952 addrlist->message = string_sprintf("%s transport called with no hosts set",
2953 tblock->name);
2954 addrlist->transport_return = PANIC;
2955 return FALSE; /* Only top address has status */
2956 }
2957
2958 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
2959 ob->hosts);
2960
2961 /* If the transport's host list contains no '$' characters, and we are not
2962 randomizing, it is fixed and therefore a chain of hosts can be built once
2963 and for all, and remembered for subsequent use by other calls to this
2964 transport. If, on the other hand, the host list does contain '$', or we are
2965 randomizing its order, we have to rebuild it each time. In the fixed case,
2966 as the hosts string will never be used again, it doesn't matter that we
2967 replace all the : characters with zeros. */
2968
2969 if (ob->hostlist == NULL)
2970 {
2971 uschar *s = ob->hosts;
2972
2973 if (Ustrchr(s, '$') != NULL)
2974 {
2975 if (!(expanded_hosts = expand_string(s)))
2976 {
2977 addrlist->message = string_sprintf("failed to expand list of hosts "
2978 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
2979 addrlist->transport_return = search_find_defer? DEFER : PANIC;
2980 return FALSE; /* Only top address has status */
2981 }
2982 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
2983 "\"%s\"\n", s, expanded_hosts);
2984 s = expanded_hosts;
2985 }
2986 else
2987 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
2988
2989 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
2990
2991 /* Check that the expansion yielded something useful. */
2992 if (hostlist == NULL)
2993 {
2994 addrlist->message =
2995 string_sprintf("%s transport has empty hosts setting", tblock->name);
2996 addrlist->transport_return = PANIC;
2997 return FALSE; /* Only top address has status */
2998 }
2999
3000 /* If there was no expansion of hosts, save the host list for
3001 next time. */
3002
3003 if (!expanded_hosts) ob->hostlist = hostlist;
3004 }
3005
3006 /* This is not the first time this transport has been run in this delivery;
3007 the host list was built previously. */
3008
3009 else
3010 hostlist = ob->hostlist;
3011 }
3012
3013 /* The host list was supplied with the address. If hosts_randomize is set, we
3014 must sort it into a random order if it did not come from MX records and has not
3015 already been randomized (but don't bother if continuing down an existing
3016 connection). */
3017
3018 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continuing)
3019 {
3020 host_item *newlist = NULL;
3021 while (hostlist != NULL)
3022 {
3023 host_item *h = hostlist;
3024 hostlist = hostlist->next;
3025
3026 h->sort_key = random_number(100);
3027
3028 if (newlist == NULL)
3029 {
3030 h->next = NULL;
3031 newlist = h;
3032 }
3033 else if (h->sort_key < newlist->sort_key)
3034 {
3035 h->next = newlist;
3036 newlist = h;
3037 }
3038 else
3039 {
3040 host_item *hh = newlist;
3041 while (hh->next != NULL)
3042 {
3043 if (h->sort_key < hh->next->sort_key) break;
3044 hh = hh->next;
3045 }
3046 h->next = hh->next;
3047 hh->next = h;
3048 }
3049 }
3050
3051 hostlist = addrlist->host_list = newlist;
3052 }
3053
3054 /* Sort out the default port. */
3055
3056 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
3057
3058 /* For each host-plus-IP-address on the list:
3059
3060 . If this is a continued delivery and the host isn't the one with the
3061 current connection, skip.
3062
3063 . If the status is unusable (i.e. previously failed or retry checked), skip.
3064
3065 . If no IP address set, get the address, either by turning the name into
3066 an address, calling gethostbyname if gethostbyname is on, or by calling
3067 the DNS. The DNS may yield multiple addresses, in which case insert the
3068 extra ones into the list.
3069
3070 . Get the retry data if not previously obtained for this address and set the
3071 field which remembers the state of this address. Skip if the retry time is
3072 not reached. If not, remember whether retry data was found. The retry string
3073 contains both the name and the IP address.
3074
3075 . Scan the list of addresses and mark those whose status is DEFER as
3076 PENDING_DEFER. These are the only ones that will be processed in this cycle
3077 of the hosts loop.
3078
3079 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
3080 Some addresses may be successfully delivered, others may fail, and yet
3081 others may get temporary errors and so get marked DEFER.
3082
3083 . The return from the delivery attempt is OK if a connection was made and a
3084 valid SMTP dialogue was completed. Otherwise it is DEFER.
3085
3086 . If OK, add a "remove" retry item for this host/IPaddress, if any.
3087
3088 . If fail to connect, or other defer state, add a retry item.
3089
3090 . If there are any addresses whose status is still DEFER, carry on to the
3091 next host/IPaddress, unless we have tried the number of hosts given
3092 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
3093 there is some fancy logic for hosts_max_try that means its limit can be
3094 overstepped in some circumstances.
3095
3096 If we get to the end of the list, all hosts have deferred at least one address,
3097 or not reached their retry times. If delay_after_cutoff is unset, it requests a
3098 delivery attempt to those hosts whose last try was before the arrival time of
3099 the current message. To cope with this, we have to go round the loop a second
3100 time. After that, set the status and error data for any addresses that haven't
3101 had it set already. */
3102
3103 for (cutoff_retry = 0; expired &&
3104 cutoff_retry < ((ob->delay_after_cutoff)? 1 : 2);
3105 cutoff_retry++)
3106 {
3107 host_item *nexthost = NULL;
3108 int unexpired_hosts_tried = 0;
3109
3110 for (host = hostlist;
3111 host != NULL &&
3112 unexpired_hosts_tried < ob->hosts_max_try &&
3113 total_hosts_tried < ob->hosts_max_try_hardlimit;
3114 host = nexthost)
3115 {
3116 int rc;
3117 int host_af;
3118 uschar *rs;
3119 BOOL serialized = FALSE;
3120 BOOL host_is_expired = FALSE;
3121 BOOL message_defer = FALSE;
3122 BOOL ifchanges = FALSE;
3123 BOOL some_deferred = FALSE;
3124 address_item *first_addr = NULL;
3125 uschar *interface = NULL;
3126 uschar *retry_host_key = NULL;
3127 uschar *retry_message_key = NULL;
3128 uschar *serialize_key = NULL;
3129
3130 /* Default next host is next host. :-) But this can vary if the
3131 hosts_max_try limit is hit (see below). It may also be reset if a host
3132 address is looked up here (in case the host was multihomed). */
3133
3134 nexthost = host->next;
3135
3136 /* If the address hasn't yet been obtained from the host name, look it up
3137 now, unless the host is already marked as unusable. If it is marked as
3138 unusable, it means that the router was unable to find its IP address (in
3139 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
3140 the lookup failed last time. We don't get this far if *all* MX records
3141 point to non-existent hosts; that is treated as a hard error.
3142
3143 We can just skip this host entirely. When the hosts came from the router,
3144 the address will timeout based on the other host(s); when the address is
3145 looked up below, there is an explicit retry record added.
3146
3147 Note that we mustn't skip unusable hosts if the address is not unset; they
3148 may be needed as expired hosts on the 2nd time round the cutoff loop. */
3149
3150 if (host->address == NULL)
3151 {
3152 int new_port, flags;
3153 host_item *hh;
3154
3155 if (host->status >= hstatus_unusable)
3156 {
3157 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
3158 host->name);
3159 continue;
3160 }
3161
3162 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
3163
3164 /* The host name is permitted to have an attached port. Find it, and
3165 strip it from the name. Just remember it for now. */
3166
3167 new_port = host_item_get_port(host);
3168
3169 /* Count hosts looked up */
3170
3171 hosts_looked_up++;
3172
3173 /* Find by name if so configured, or if it's an IP address. We don't
3174 just copy the IP address, because we need the test-for-local to happen. */
3175
3176 flags = HOST_FIND_BY_A;
3177 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
3178 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
3179
3180 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
3181 rc = host_find_byname(host, NULL, flags, NULL, TRUE);
3182 else
3183 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
3184 ob->dnssec_request_domains, ob->dnssec_require_domains,
3185 NULL, NULL);
3186
3187 /* Update the host (and any additional blocks, resulting from
3188 multihoming) with a host-specific port, if any. */
3189
3190 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
3191
3192 /* Failure to find the host at this time (usually DNS temporary failure)
3193 is really a kind of routing failure rather than a transport failure.
3194 Therefore we add a retry item of the routing kind, not to stop us trying
3195 to look this name up here again, but to ensure the address gets timed
3196 out if the failures go on long enough. A complete failure at this point
3197 commonly points to a configuration error, but the best action is still
3198 to carry on for the next host. */
3199
3200 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
3201 {
3202 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
3203 expired = FALSE;
3204 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
3205 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
3206 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
3207 host->status = hstatus_unusable;
3208
3209 for (addr = addrlist; addr != NULL; addr = addr->next)
3210 {
3211 if (addr->transport_return != DEFER) continue;
3212 addr->basic_errno = ERRNO_UNKNOWNHOST;
3213 addr->message =
3214 string_sprintf("failed to lookup IP address for %s", host->name);
3215 }
3216 continue;
3217 }
3218
3219 /* If the host is actually the local host, we may have a problem, or
3220 there may be some cunning configuration going on. In the problem case,
3221 log things and give up. The default transport status is already DEFER. */
3222
3223 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
3224 {
3225 for (addr = addrlist; addr != NULL; addr = addr->next)
3226 {
3227 addr->basic_errno = 0;
3228 addr->message = string_sprintf("%s transport found host %s to be "
3229 "local", tblock->name, host->name);
3230 }
3231 goto END_TRANSPORT;
3232 }
3233 } /* End of block for IP address lookup */
3234
3235 /* If this is a continued delivery, we are interested only in the host
3236 which matches the name of the existing open channel. The check is put
3237 here after the local host lookup, in case the name gets expanded as a
3238 result of the lookup. Set expired FALSE, to save the outer loop executing
3239 twice. */
3240
3241 if (continuing && (Ustrcmp(continue_hostname, host->name) != 0 ||
3242 Ustrcmp(continue_host_address, host->address) != 0))
3243 {
3244 expired = FALSE;
3245 continue; /* With next host */
3246 }
3247
3248 /* Reset the default next host in case a multihomed host whose addresses
3249 are not looked up till just above added to the host list. */
3250
3251 nexthost = host->next;
3252
3253 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
3254 domain is in queue_smtp_domains, we don't actually want to attempt any
3255 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
3256 there is a lookup defer in queue_smtp_domains, proceed as if the domain
3257 were not in it. We don't want to hold up all SMTP deliveries! Except when
3258 doing a two-stage queue run, don't do this if forcing. */
3259
3260 if ((!deliver_force || queue_2stage) && (queue_smtp ||
3261 match_isinlist(addrlist->domain,
3262 (const uschar **)&queue_smtp_domains, 0,
3263 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
3264 {
3265 expired = FALSE;
3266 for (addr = addrlist; addr != NULL; addr = addr->next)
3267 {
3268 if (addr->transport_return != DEFER) continue;
3269 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
3270 }
3271 continue; /* With next host */
3272 }
3273
3274 /* Count hosts being considered - purely for an intelligent comment
3275 if none are usable. */
3276
3277 hosts_total++;
3278
3279 /* Set $host and $host address now in case they are needed for the
3280 interface expansion or the serialize_hosts check; they remain set if an
3281 actual delivery happens. */
3282
3283 deliver_host = host->name;
3284 deliver_host_address = host->address;
3285 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
3286 : host->dnssec == DS_NO ? US"no"
3287 : US"";
3288
3289 /* Set up a string for adding to the retry key if the port number is not
3290 the standard SMTP port. A host may have its own port setting that overrides
3291 the default. */
3292
3293 pistring = string_sprintf(":%d", (host->port == PORT_NONE)?
3294 port : host->port);
3295 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
3296
3297 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
3298 string changes upon expansion, we must add it to the key that is used for
3299 retries, because connections to the same host from a different interface
3300 should be treated separately. */
3301
3302 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET : AF_INET6;
3303 if (!smtp_get_interface(ob->interface, host_af, addrlist, &ifchanges,
3304 &interface, tid))
3305 return FALSE;
3306 if (ifchanges) pistring = string_sprintf("%s/%s", pistring, interface);
3307
3308 /* The first time round the outer loop, check the status of the host by
3309 inspecting the retry data. The second time round, we are interested only
3310 in expired hosts that haven't been tried since this message arrived. */
3311
3312 if (cutoff_retry == 0)
3313 {
3314 BOOL incl_ip;
3315 /* Ensure the status of the address is set by checking retry data if
3316 necessary. There may be host-specific retry data (applicable to all
3317 messages) and also data for retries of a specific message at this host.
3318 If either of these retry records are actually read, the keys used are
3319 returned to save recomputing them later. */
3320
3321 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3322 US"retry_include_ip_address", ob->retry_include_ip_address,
3323 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3324 continue; /* with next host */
3325
3326 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
3327 incl_ip, &retry_host_key, &retry_message_key);
3328
3329 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
3330 (host->address == NULL)? US"" : host->address, pistring,
3331 (host->status == hstatus_usable)? "usable" :
3332 (host->status == hstatus_unusable)? "unusable" :
3333 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
3334
3335 /* Skip this address if not usable at this time, noting if it wasn't
3336 actually expired, both locally and in the address. */
3337
3338 switch (host->status)
3339 {
3340 case hstatus_unusable:
3341 expired = FALSE;
3342 setflag(addrlist, af_retry_skipped);
3343 /* Fall through */
3344
3345 case hstatus_unusable_expired:
3346 switch (host->why)
3347 {
3348 case hwhy_retry: hosts_retry++; break;
3349 case hwhy_failed: hosts_fail++; break;
3350 case hwhy_deferred: hosts_defer++; break;
3351 }
3352
3353 /* If there was a retry message key, implying that previously there
3354 was a message-specific defer, we don't want to update the list of
3355 messages waiting for these hosts. */
3356
3357 if (retry_message_key != NULL) update_waiting = FALSE;
3358 continue; /* With the next host or IP address */
3359 }
3360 }
3361
3362 /* Second time round the loop: if the address is set but expired, and
3363 the message is newer than the last try, let it through. */
3364
3365 else
3366 {
3367 if (host->address == NULL ||
3368 host->status != hstatus_unusable_expired ||
3369 host->last_try > received_time)
3370 continue;
3371 DEBUG(D_transport)
3372 debug_printf("trying expired host %s [%s]%s\n",
3373 host->name, host->address, pistring);
3374 host_is_expired = TRUE;
3375 }
3376
3377 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
3378 it remains TRUE only if all hosts are expired and none are actually tried.
3379 */
3380
3381 expired = FALSE;
3382
3383 /* If this host is listed as one to which access must be serialized,
3384 see if another Exim process has a connection to it, and if so, skip
3385 this host. If not, update the database to record our connection to it
3386 and remember this for later deletion. Do not do any of this if we are
3387 sending the message down a pre-existing connection. */
3388
3389 if (!continuing &&
3390 verify_check_given_host(&ob->serialize_hosts, host) == OK)
3391 {
3392 serialize_key = string_sprintf("host-serialize-%s", host->name);
3393 if (!enq_start(serialize_key))
3394 {
3395 DEBUG(D_transport)
3396 debug_printf("skipping host %s because another Exim process "
3397 "is connected to it\n", host->name);
3398 hosts_serial++;
3399 continue;
3400 }
3401 serialized = TRUE;
3402 }
3403
3404 /* OK, we have an IP address that is not waiting for its retry time to
3405 arrive (it might be expired) OR (second time round the loop) we have an
3406 expired host that hasn't been tried since the message arrived. Have a go
3407 at delivering the message to it. First prepare the addresses by flushing
3408 out the result of previous attempts, and finding the first address that
3409 is still to be delivered. */
3410
3411 first_addr = prepare_addresses(addrlist, host);
3412
3413 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
3414 message_id, host->name, host->address, addrlist->address,
3415 (addrlist->next == NULL)? "" : ", ...");
3416
3417 set_process_info("delivering %s to %s [%s] (%s%s)",
3418 message_id, host->name, host->address, addrlist->address,
3419 (addrlist->next == NULL)? "" : ", ...");
3420
3421 /* This is not for real; don't do the delivery. If there are
3422 any remaining hosts, list them. */
3423
3424 if (dont_deliver)
3425 {
3426 host_item *host2;
3427 set_errno(addrlist, 0, NULL, OK, FALSE, NULL);
3428 for (addr = addrlist; addr != NULL; addr = addr->next)
3429 {
3430 addr->host_used = host;
3431 addr->special_action = '*';
3432 addr->message = US"delivery bypassed by -N option";
3433 }
3434 DEBUG(D_transport)
3435 {
3436 debug_printf("*** delivery by %s transport bypassed by -N option\n"
3437 "*** host and remaining hosts:\n", tblock->name);
3438 for (host2 = host; host2 != NULL; host2 = host2->next)
3439 debug_printf(" %s [%s]\n", host2->name,
3440 (host2->address == NULL)? US"unset" : host2->address);
3441 }
3442 rc = OK;
3443 }
3444
3445 /* This is for real. If the host is expired, we don't count it for
3446 hosts_max_retry. This ensures that all hosts must expire before an address
3447 is timed out, unless hosts_max_try_hardlimit (which protects against
3448 lunatic DNS configurations) is reached.
3449
3450 If the host is not expired and we are about to hit the hosts_max_retry
3451 limit, check to see if there is a subsequent hosts with a different MX
3452 value. If so, make that the next host, and don't count this one. This is a
3453 heuristic to make sure that different MXs do get tried. With a normal kind
3454 of retry rule, they would get tried anyway when the earlier hosts were
3455 delayed, but if the domain has a "retry every time" type of rule - as is
3456 often used for the the very large ISPs, that won't happen. */
3457
3458 else
3459 {
3460 host_item * thost;
3461 /* Make a copy of the host if it is local to this invocation
3462 of the transport. */
3463
3464 if (expanded_hosts)
3465 {
3466 thost = store_get(sizeof(host_item));
3467 *thost = *host;
3468 thost->name = string_copy(host->name);
3469 thost->address = string_copy(host->address);
3470 }
3471 else
3472 thost = host;
3473
3474 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
3475 {
3476 host_item *h;
3477 DEBUG(D_transport)
3478 debug_printf("hosts_max_try limit reached with this host\n");
3479 for (h = host; h != NULL; h = h->next)
3480 if (h->mx != host->mx) break;
3481 if (h != NULL)
3482 {
3483 nexthost = h;
3484 unexpired_hosts_tried--;
3485 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
3486 "and will be tried\n");
3487 }
3488 }
3489
3490 /* Attempt the delivery. */
3491
3492 total_hosts_tried++;
3493 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
3494 &message_defer, FALSE);
3495
3496 /* Yield is one of:
3497 OK => connection made, each address contains its result;
3498 message_defer is set for message-specific defers (when all
3499 recipients are marked defer)
3500 DEFER => there was a non-message-specific delivery problem;
3501 ERROR => there was a problem setting up the arguments for a filter,
3502 or there was a problem with expanding added headers
3503 */
3504
3505 /* If the result is not OK, there was a non-message-specific problem.
3506 If the result is DEFER, we need to write to the logs saying what happened
3507 for this particular host, except in the case of authentication and TLS
3508 failures, where the log has already been written. If all hosts defer a
3509 general message is written at the end. */
3510
3511 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL &&
3512 first_addr->basic_errno != ERRNO_TLSFAILURE)
3513 write_logs(first_addr, host);
3514
3515 #ifdef EXPERIMENTAL_EVENT
3516 if (rc == DEFER)
3517 deferred_event_raise(first_addr, host);
3518 #endif
3519
3520 /* If STARTTLS was accepted, but there was a failure in setting up the
3521 TLS session (usually a certificate screwup), and the host is not in
3522 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
3523 TLS forcibly turned off. We have to start from scratch with a new SMTP
3524 connection. That's why the retry is done from here, not from within
3525 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
3526 session, so the in-clear transmission after those errors, if permitted,
3527 happens inside smtp_deliver().] */
3528
3529 #ifdef SUPPORT_TLS
3530 if ( rc == DEFER
3531 && first_addr->basic_errno == ERRNO_TLSFAILURE
3532 && ob->tls_tempfail_tryclear
3533 && verify_check_given_host(&ob->hosts_require_tls, host) != OK
3534 )
3535 {
3536 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
3537 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
3538 first_addr = prepare_addresses(addrlist, host);
3539 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
3540 &message_defer, TRUE);
3541 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
3542 write_logs(first_addr, host);
3543 # ifdef EXPERIMENTAL_EVENT
3544 if (rc == DEFER)
3545 deferred_event_raise(first_addr, host);
3546 # endif
3547 }
3548 #endif /*SUPPORT_TLS*/
3549 }
3550
3551 /* Delivery attempt finished */
3552
3553 rs = (rc == OK)? US"OK" : (rc == DEFER)? US"DEFER" : (rc == ERROR)?
3554 US"ERROR" : US"?";
3555
3556 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
3557 message_id, host->name, host->address, addrlist->address,
3558 (addrlist->next == NULL)? "" : " (& others)", rs);
3559
3560 /* Release serialization if set up */
3561
3562 if (serialized) enq_end(serialize_key);
3563
3564 /* If the result is DEFER, or if a host retry record is known to exist, we
3565 need to add an item to the retry chain for updating the retry database
3566 at the end of delivery. We only need to add the item to the top address,
3567 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
3568 for any other delivery attempts using the same address. (It is copied into
3569 the unusable tree at the outer level, so even if different address blocks
3570 contain the same address, it still won't get tried again.) */
3571
3572 if (rc == DEFER || retry_host_key != NULL)
3573 {
3574 int delete_flag = (rc != DEFER)? rf_delete : 0;
3575 if (retry_host_key == NULL)
3576 {
3577 BOOL incl_ip;
3578 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3579 US"retry_include_ip_address", ob->retry_include_ip_address,
3580 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3581 incl_ip = TRUE; /* error; use most-specific retry record */
3582
3583 retry_host_key = incl_ip ?
3584 string_sprintf("T:%S:%s%s", host->name, host->address, pistring) :
3585 string_sprintf("T:%S%s", host->name, pistring);
3586 }
3587
3588 /* If a delivery of another message over an existing SMTP connection
3589 yields DEFER, we do NOT set up retry data for the host. This covers the
3590 case when there are delays in routing the addresses in the second message
3591 that are so long that the server times out. This is alleviated by not
3592 routing addresses that previously had routing defers when handling an
3593 existing connection, but even so, this case may occur (e.g. if a
3594 previously happily routed address starts giving routing defers). If the
3595 host is genuinely down, another non-continued message delivery will
3596 notice it soon enough. */
3597
3598 if (delete_flag != 0 || !continuing)
3599 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
3600
3601 /* We may have tried an expired host, if its retry time has come; ensure
3602 the status reflects the expiry for the benefit of any other addresses. */
3603
3604 if (rc == DEFER)
3605 {
3606 host->status = (host_is_expired)?
3607 hstatus_unusable_expired : hstatus_unusable;
3608 host->why = hwhy_deferred;
3609 }
3610 }
3611
3612 /* If message_defer is set (host was OK, but every recipient got deferred
3613 because of some message-specific problem), or if that had happened
3614 previously so that a message retry key exists, add an appropriate item
3615 to the retry chain. Note that if there was a message defer but now there is
3616 a host defer, the message defer record gets deleted. That seems perfectly
3617 reasonable. Also, stop the message from being remembered as waiting
3618 for specific hosts. */
3619
3620 if (message_defer || retry_message_key != NULL)
3621 {
3622 int delete_flag = message_defer? 0 : rf_delete;
3623 if (retry_message_key == NULL)
3624 {
3625 BOOL incl_ip;
3626 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3627 US"retry_include_ip_address", ob->retry_include_ip_address,
3628 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3629 incl_ip = TRUE; /* error; use most-specific retry record */
3630
3631 retry_message_key = incl_ip ?
3632 string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
3633 message_id) :
3634 string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
3635 }
3636 retry_add_item(addrlist, retry_message_key,
3637 rf_message | rf_host | delete_flag);
3638 update_waiting = FALSE;
3639 }
3640
3641 /* Any return other than DEFER (that is, OK or ERROR) means that the
3642 addresses have got their final statuses filled in for this host. In the OK
3643 case, see if any of them are deferred. */
3644
3645 if (rc == OK)
3646 {
3647 for (addr = addrlist; addr != NULL; addr = addr->next)
3648 {
3649 if (addr->transport_return == DEFER)
3650 {
3651 some_deferred = TRUE;
3652 break;
3653 }
3654 }
3655 }
3656
3657 /* If no addresses deferred or the result was ERROR, return. We do this for
3658 ERROR because a failing filter set-up or add_headers expansion is likely to
3659 fail for any host we try. */
3660
3661 if (rc == ERROR || (rc == OK && !some_deferred))
3662 {
3663 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3664 return TRUE; /* Each address has its status */
3665 }
3666
3667 /* If the result was DEFER or some individual addresses deferred, let
3668 the loop run to try other hosts with the deferred addresses, except for the
3669 case when we were trying to deliver down an existing channel and failed.
3670 Don't try any other hosts in this case. */
3671
3672 if (continuing) break;
3673
3674 /* If the whole delivery, or some individual addresses, were deferred and
3675 there are more hosts that could be tried, do not count this host towards
3676 the hosts_max_try limit if the age of the message is greater than the
3677 maximum retry time for this host. This means we may try try all hosts,
3678 ignoring the limit, when messages have been around for some time. This is
3679 important because if we don't try all hosts, the address will never time
3680 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
3681
3682 if ((rc == DEFER || some_deferred) && nexthost != NULL)
3683 {
3684 BOOL timedout;
3685 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
3686
3687 if (retry != NULL && retry->rules != NULL)
3688 {
3689 retry_rule *last_rule;
3690 for (last_rule = retry->rules;
3691 last_rule->next != NULL;
3692 last_rule = last_rule->next);
3693 timedout = time(NULL) - received_time > last_rule->timeout;
3694 }
3695 else timedout = TRUE; /* No rule => timed out */
3696
3697 if (timedout)
3698 {
3699 unexpired_hosts_tried--;
3700 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
3701 "hosts_max_try (message older than host's retry time)\n");
3702 }
3703 }
3704 } /* End of loop for trying multiple hosts. */
3705
3706 /* This is the end of the loop that repeats iff expired is TRUE and
3707 ob->delay_after_cutoff is FALSE. The second time round we will
3708 try those hosts that haven't been tried since the message arrived. */
3709
3710 DEBUG(D_transport)
3711 {
3712 debug_printf("all IP addresses skipped or deferred at least one address\n");
3713 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
3714 debug_printf("retrying IP addresses not tried since message arrived\n");
3715 }
3716 }
3717
3718
3719 /* Get here if all IP addresses are skipped or defer at least one address. In
3720 MUA wrapper mode, this will happen only for connection or other non-message-
3721 specific failures. Force the delivery status for all addresses to FAIL. */
3722
3723 if (mua_wrapper)
3724 {
3725 for (addr = addrlist; addr != NULL; addr = addr->next)
3726 addr->transport_return = FAIL;
3727 goto END_TRANSPORT;
3728 }
3729
3730 /* In the normal, non-wrapper case, add a standard message to each deferred
3731 address if there hasn't been an error, that is, if it hasn't actually been
3732 tried this time. The variable "expired" will be FALSE if any deliveries were
3733 actually tried, or if there was at least one host that was not expired. That
3734 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
3735 a delivery has been tried, an error code will be set, and the failing of the
3736 message is handled by the retry code later.
3737
3738 If queue_smtp is set, or this transport was called to send a subsequent message
3739 down an existing TCP/IP connection, and something caused the host not to be
3740 found, we end up here, but can detect these cases and handle them specially. */
3741
3742 for (addr = addrlist; addr != NULL; addr = addr->next)
3743 {
3744 /* If host is not NULL, it means that we stopped processing the host list
3745 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
3746 means we need to behave as if some hosts were skipped because their retry
3747 time had not come. Specifically, this prevents the address from timing out.
3748 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
3749 hosts were tried. */
3750
3751 if (host != NULL)
3752 {
3753 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
3754 {
3755 DEBUG(D_transport)
3756 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
3757 "hosts were tried\n");
3758 }
3759 else
3760 {
3761 DEBUG(D_transport)
3762 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
3763 setflag(addr, af_retry_skipped);
3764 }
3765 }
3766
3767 if (queue_smtp) /* no deliveries attempted */
3768 {
3769 addr->transport_return = DEFER;
3770 addr->basic_errno = 0;
3771 addr->message = US"SMTP delivery explicitly queued";
3772 }
3773
3774 else if (addr->transport_return == DEFER &&
3775 (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0) &&
3776 addr->message == NULL)
3777 {
3778 addr->basic_errno = ERRNO_HRETRY;
3779 if (continue_hostname != NULL)
3780 {
3781 addr->message = US"no host found for existing SMTP connection";
3782 }
3783 else if (expired)
3784 {
3785 setflag(addr, af_pass_message); /* This is not a security risk */
3786 addr->message = (ob->delay_after_cutoff)?
3787 US"retry time not reached for any host after a long failure period" :
3788 US"all hosts have been failing for a long time and were last tried "
3789 "after this message arrived";
3790
3791 /* If we are already using fallback hosts, or there are no fallback hosts
3792 defined, convert the result to FAIL to cause a bounce. */
3793
3794 if (addr->host_list == addr->fallback_hosts ||
3795 addr->fallback_hosts == NULL)
3796 addr->transport_return = FAIL;
3797 }
3798 else
3799 {
3800 if (hosts_retry == hosts_total)
3801 addr->message = US"retry time not reached for any host";
3802 else if (hosts_fail == hosts_total)
3803 addr->message = US"all host address lookups failed permanently";
3804 else if (hosts_defer == hosts_total)
3805 addr->message = US"all host address lookups failed temporarily";
3806 else if (hosts_serial == hosts_total)
3807 addr->message = US"connection limit reached for all hosts";
3808 else if (hosts_fail+hosts_defer == hosts_total)
3809 addr->message = US"all host address lookups failed";
3810 else addr->message = US"some host address lookups failed and retry time "
3811 "not reached for other hosts or connection limit reached";
3812 }
3813 }
3814 }
3815
3816 /* Update the database which keeps information about which messages are waiting
3817 for which hosts to become available. For some message-specific errors, the
3818 update_waiting flag is turned off because we don't want follow-on deliveries in
3819 those cases. If this transport instance is explicitly limited to one message
3820 per connection then follow-on deliveries are not possible and there's no need
3821 to create/update the per-transport wait-<transport_name> database. */
3822
3823 if (update_waiting && tblock->connection_max_messages != 1)
3824 transport_update_waiting(hostlist, tblock->name);
3825
3826 END_TRANSPORT:
3827
3828 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3829
3830 return TRUE; /* Each address has its status */
3831 }
3832
3833 /* vi: aw ai sw=2
3834 */
3835 /* End of transport/smtp.c */
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