TLS: Enable ECDHE on OpenSSL, just the NIST P-256 curve. Bug 1397
[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) },
65 { "dnssec_require_domains", opt_stringptr,
66 (void *)offsetof(smtp_transport_options_block, dnssec.require) },
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, NULL }, /* dnssec_domains {request,require} */
245 TRUE, /* delay_after_cutoff */
246 FALSE, /* hosts_override */
247 FALSE, /* hosts_randomize */
248 TRUE, /* keepalive */
249 FALSE, /* lmtp_ignore_quota */
250 NULL, /* expand_retry_include_ip_address */
251 TRUE /* retry_include_ip_address */
252 #ifdef EXPERIMENTAL_SOCKS
253 ,NULL /* socks_proxy */
254 #endif
255 #ifdef SUPPORT_TLS
256 ,NULL, /* tls_certificate */
257 NULL, /* tls_crl */
258 NULL, /* tls_privatekey */
259 NULL, /* tls_require_ciphers */
260 NULL, /* gnutls_require_kx */
261 NULL, /* gnutls_require_mac */
262 NULL, /* gnutls_require_proto */
263 NULL, /* tls_sni */
264 US"system", /* tls_verify_certificates */
265 EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
266 /* tls_dh_min_bits */
267 TRUE, /* tls_tempfail_tryclear */
268 NULL, /* tls_verify_hosts */
269 US"*", /* tls_try_verify_hosts */
270 US"*" /* tls_verify_cert_hostnames */
271 #endif
272 #ifndef DISABLE_DKIM
273 ,NULL, /* dkim_canon */
274 NULL, /* dkim_domain */
275 NULL, /* dkim_private_key */
276 NULL, /* dkim_selector */
277 NULL, /* dkim_sign_headers */
278 NULL /* dkim_strict */
279 #endif
280 };
281
282 /* some DSN flags for use later */
283
284 static int rf_list[] = {rf_notify_never, rf_notify_success,
285 rf_notify_failure, rf_notify_delay };
286
287 static uschar *rf_names[] = { US"NEVER", US"SUCCESS", US"FAILURE", US"DELAY" };
288
289
290
291 /* Local statics */
292
293 static uschar *smtp_command; /* Points to last cmd for error messages */
294 static uschar *mail_command; /* Points to MAIL cmd for error messages */
295 static BOOL update_waiting; /* TRUE to update the "wait" database */
296
297
298 /*************************************************
299 * Setup entry point *
300 *************************************************/
301
302 /* This function is called when the transport is about to be used,
303 but before running it in a sub-process. It is used for two things:
304
305 (1) To set the fallback host list in addresses, when delivering.
306 (2) To pass back the interface, port, protocol, and other options, for use
307 during callout verification.
308
309 Arguments:
310 tblock pointer to the transport instance block
311 addrlist list of addresses about to be transported
312 tf if not NULL, pointer to block in which to return options
313 uid the uid that will be set (not used)
314 gid the gid that will be set (not used)
315 errmsg place for error message (not used)
316
317 Returns: OK always (FAIL, DEFER not used)
318 */
319
320 static int
321 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
322 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
323 {
324 smtp_transport_options_block *ob =
325 (smtp_transport_options_block *)(tblock->options_block);
326
327 errmsg = errmsg; /* Keep picky compilers happy */
328 uid = uid;
329 gid = gid;
330
331 /* Pass back options if required. This interface is getting very messy. */
332
333 if (tf != NULL)
334 {
335 tf->interface = ob->interface;
336 tf->port = ob->port;
337 tf->protocol = ob->protocol;
338 tf->hosts = ob->hosts;
339 tf->hosts_override = ob->hosts_override;
340 tf->hosts_randomize = ob->hosts_randomize;
341 tf->gethostbyname = ob->gethostbyname;
342 tf->qualify_single = ob->dns_qualify_single;
343 tf->search_parents = ob->dns_search_parents;
344 tf->helo_data = ob->helo_data;
345 }
346
347 /* Set the fallback host list for all the addresses that don't have fallback
348 host lists, provided that the local host wasn't present in the original host
349 list. */
350
351 if (!testflag(addrlist, af_local_host_removed))
352 {
353 for (; addrlist != NULL; addrlist = addrlist->next)
354 if (addrlist->fallback_hosts == NULL)
355 addrlist->fallback_hosts = ob->fallback_hostlist;
356 }
357
358 return OK;
359 }
360
361
362
363 /*************************************************
364 * Initialization entry point *
365 *************************************************/
366
367 /* Called for each instance, after its options have been read, to
368 enable consistency checks to be done, or anything else that needs
369 to be set up.
370
371 Argument: pointer to the transport instance block
372 Returns: nothing
373 */
374
375 void
376 smtp_transport_init(transport_instance *tblock)
377 {
378 smtp_transport_options_block *ob =
379 (smtp_transport_options_block *)(tblock->options_block);
380
381 /* Retry_use_local_part defaults FALSE if unset */
382
383 if (tblock->retry_use_local_part == TRUE_UNSET)
384 tblock->retry_use_local_part = FALSE;
385
386 /* Set the default port according to the protocol */
387
388 if (ob->port == NULL)
389 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
390 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
391
392 /* Set up the setup entry point, to be called before subprocesses for this
393 transport. */
394
395 tblock->setup = smtp_transport_setup;
396
397 /* Complain if any of the timeouts are zero. */
398
399 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
400 ob->final_timeout <= 0)
401 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
402 "command, data, or final timeout value is zero for %s transport",
403 tblock->name);
404
405 /* If hosts_override is set and there are local hosts, set the global
406 flag that stops verify from showing router hosts. */
407
408 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
409
410 /* If there are any fallback hosts listed, build a chain of host items
411 for them, but do not do any lookups at this time. */
412
413 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
414
415 #ifdef SUPPORT_TLS
416 if ( ob->gnutls_require_kx
417 || ob->gnutls_require_mac
418 || ob->gnutls_require_proto)
419 log_write(0, LOG_MAIN, "WARNING: smtp transport options"
420 " gnutls_require_kx, gnutls_require_mac and gnutls_require_protocols"
421 " are obsolete\n");
422 #endif
423 }
424
425
426
427
428
429 /*************************************************
430 * Set delivery info into all active addresses *
431 *************************************************/
432
433 /* Only addresses whose status is >= PENDING are relevant. A lesser
434 status means that an address is not currently being processed.
435
436 Arguments:
437 addrlist points to a chain of addresses
438 errno_value to put in each address's errno field
439 msg to put in each address's message field
440 rc to put in each address's transport_return field
441 pass_message if TRUE, set the "pass message" flag in the address
442 host if set, mark addrs as having used this host
443
444 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
445 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
446 this particular type of timeout.
447
448 Returns: nothing
449 */
450
451 static void
452 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
453 BOOL pass_message, host_item * host)
454 {
455 address_item *addr;
456 int orvalue = 0;
457 if (errno_value == ERRNO_CONNECTTIMEOUT)
458 {
459 errno_value = ETIMEDOUT;
460 orvalue = RTEF_CTOUT;
461 }
462 for (addr = addrlist; addr != NULL; addr = addr->next)
463 if (addr->transport_return >= PENDING)
464 {
465 addr->basic_errno = errno_value;
466 addr->more_errno |= orvalue;
467 if (msg != NULL)
468 {
469 addr->message = msg;
470 if (pass_message) setflag(addr, af_pass_message);
471 }
472 addr->transport_return = rc;
473 if (host)
474 addr->host_used = host;
475 }
476 }
477
478
479
480 /*************************************************
481 * Check an SMTP response *
482 *************************************************/
483
484 /* This function is given an errno code and the SMTP response buffer
485 to analyse, together with the host identification for generating messages. It
486 sets an appropriate message and puts the first digit of the response code into
487 the yield variable. If no response was actually read, a suitable digit is
488 chosen.
489
490 Arguments:
491 host the current host, to get its name for messages
492 errno_value pointer to the errno value
493 more_errno from the top address for use with ERRNO_FILTER_FAIL
494 buffer the SMTP response buffer
495 yield where to put a one-digit SMTP response code
496 message where to put an errror message
497 pass_message set TRUE if message is an SMTP response
498
499 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
500 */
501
502 static BOOL
503 check_response(host_item *host, int *errno_value, int more_errno,
504 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
505 {
506 uschar *pl = US"";
507
508 if (smtp_use_pipelining &&
509 (Ustrcmp(smtp_command, "MAIL") == 0 ||
510 Ustrcmp(smtp_command, "RCPT") == 0 ||
511 Ustrcmp(smtp_command, "DATA") == 0))
512 pl = US"pipelined ";
513
514 *yield = '4'; /* Default setting is to give a temporary error */
515
516 /* Handle response timeout */
517
518 if (*errno_value == ETIMEDOUT)
519 {
520 *message = US string_sprintf("SMTP timeout after %s%s",
521 pl, smtp_command);
522 if (transport_count > 0)
523 *message = US string_sprintf("%s (%d bytes written)", *message,
524 transport_count);
525 return FALSE;
526 }
527
528 /* Handle malformed SMTP response */
529
530 if (*errno_value == ERRNO_SMTPFORMAT)
531 {
532 const uschar *malfresp = string_printing(buffer);
533 while (isspace(*malfresp)) malfresp++;
534 *message = *malfresp == 0
535 ? string_sprintf("Malformed SMTP reply (an empty line) "
536 "in response to %s%s", pl, smtp_command)
537 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
538 pl, smtp_command, malfresp);
539 return FALSE;
540 }
541
542 /* Handle a failed filter process error; can't send QUIT as we mustn't
543 end the DATA. */
544
545 if (*errno_value == ERRNO_FILTER_FAIL)
546 {
547 *message = US string_sprintf("transport filter process failed (%d)%s",
548 more_errno,
549 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
550 return FALSE;
551 }
552
553 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
554 end the DATA. */
555
556 if (*errno_value == ERRNO_CHHEADER_FAIL)
557 {
558 *message =
559 US string_sprintf("failed to expand headers_add or headers_remove: %s",
560 expand_string_message);
561 return FALSE;
562 }
563
564 /* Handle failure to write a complete data block */
565
566 if (*errno_value == ERRNO_WRITEINCOMPLETE)
567 {
568 *message = US string_sprintf("failed to write a data block");
569 return FALSE;
570 }
571
572 #ifdef EXPERIMENTAL_INTERNATIONAL
573 /* Handle lack of advertised SMTPUTF8, for international message */
574 if (*errno_value == ERRNO_UTF8_FWD)
575 {
576 *message = US string_sprintf("utf8 support required but not offered for forwarding");
577 DEBUG(D_deliver|D_transport) debug_printf("%s\n", *message);
578 return TRUE;
579 }
580 #endif
581
582 /* Handle error responses from the remote mailer. */
583
584 if (buffer[0] != 0)
585 {
586 const uschar *s = string_printing(buffer);
587 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
588 "%s", pl, smtp_command, s);
589 *pass_message = TRUE;
590 *yield = buffer[0];
591 return TRUE;
592 }
593
594 /* No data was read. If there is no errno, this must be the EOF (i.e.
595 connection closed) case, which causes deferral. An explicit connection reset
596 error has the same effect. Otherwise, put the host's identity in the message,
597 leaving the errno value to be interpreted as well. In all cases, we have to
598 assume the connection is now dead. */
599
600 if (*errno_value == 0 || *errno_value == ECONNRESET)
601 {
602 *errno_value = ERRNO_SMTPCLOSED;
603 *message = US string_sprintf("Remote host closed connection "
604 "in response to %s%s", pl, smtp_command);
605 }
606 else *message = US string_sprintf("%s [%s]", host->name, host->address);
607
608 return FALSE;
609 }
610
611
612
613 /*************************************************
614 * Write error message to logs *
615 *************************************************/
616
617 /* This writes to the main log and to the message log.
618
619 Arguments:
620 addr the address item containing error information
621 host the current host
622
623 Returns: nothing
624 */
625
626 static void
627 write_logs(address_item *addr, host_item *host)
628 {
629 uschar * message = string_sprintf("H=%s [%s]", host->name, host->address);
630
631 if (addr->message)
632 {
633 message = string_sprintf("%s: %s", message, addr->message);
634 if (addr->basic_errno > 0)
635 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
636 log_write(0, LOG_MAIN, "%s", message);
637 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
638 }
639 else
640 {
641 if (log_extra_selector & LX_outgoing_port)
642 message = string_sprintf("%s:%d", message,
643 host->port == PORT_NONE ? 25 : host->port);
644 log_write(0, LOG_MAIN, "%s %s", message, strerror(addr->basic_errno));
645 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), message,
646 strerror(addr->basic_errno));
647 }
648 }
649
650 static void
651 msglog_line(host_item * host, uschar * message)
652 {
653 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
654 host->name, host->address, message);
655 }
656
657
658
659 #ifdef EXPERIMENTAL_EVENT
660 /*************************************************
661 * Post-defer action *
662 *************************************************/
663
664 /* This expands an arbitrary per-transport string.
665 It might, for example, be used to write to the database log.
666
667 Arguments:
668 addr the address item containing error information
669 host the current host
670
671 Returns: nothing
672 */
673
674 static void
675 deferred_event_raise(address_item *addr, host_item *host)
676 {
677 uschar * action = addr->transport->event_action;
678 const uschar * save_domain;
679 uschar * save_local;
680
681 if (!action)
682 return;
683
684 save_domain = deliver_domain;
685 save_local = deliver_localpart;
686
687 /*XXX would ip & port already be set up? */
688 deliver_host_address = string_copy(host->address);
689 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
690 event_defer_errno = addr->basic_errno;
691
692 router_name = addr->router->name;
693 transport_name = addr->transport->name;
694 deliver_domain = addr->domain;
695 deliver_localpart = addr->local_part;
696
697 (void) event_raise(action, US"msg:host:defer",
698 addr->message
699 ? addr->basic_errno > 0
700 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
701 : string_copy(addr->message)
702 : addr->basic_errno > 0
703 ? string_copy(US strerror(addr->basic_errno))
704 : NULL);
705
706 deliver_localpart = save_local;
707 deliver_domain = save_domain;
708 router_name = transport_name = NULL;
709 }
710 #endif
711
712 /*************************************************
713 * Synchronize SMTP responses *
714 *************************************************/
715
716 /* This function is called from smtp_deliver() to receive SMTP responses from
717 the server, and match them up with the commands to which they relate. When
718 PIPELINING is not in use, this function is called after every command, and is
719 therefore somewhat over-engineered, but it is simpler to use a single scheme
720 that works both with and without PIPELINING instead of having two separate sets
721 of code.
722
723 The set of commands that are buffered up with pipelining may start with MAIL
724 and may end with DATA; in between are RCPT commands that correspond to the
725 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
726 etc.) are never buffered.
727
728 Errors after MAIL or DATA abort the whole process leaving the response in the
729 buffer. After MAIL, pending responses are flushed, and the original command is
730 re-instated in big_buffer for error messages. For RCPT commands, the remote is
731 permitted to reject some recipient addresses while accepting others. However
732 certain errors clearly abort the whole process. Set the value in
733 transport_return to PENDING_OK if the address is accepted. If there is a
734 subsequent general error, it will get reset accordingly. If not, it will get
735 converted to OK at the end.
736
737 Arguments:
738 addrlist the complete address list
739 include_affixes TRUE if affixes include in RCPT
740 sync_addr ptr to the ptr of the one to start scanning at (updated)
741 host the host we are connected to
742 count the number of responses to read
743 address_retry_
744 include_sender true if 4xx retry is to include the sender it its key
745 pending_MAIL true if the first response is for MAIL
746 pending_DATA 0 if last command sent was not DATA
747 +1 if previously had a good recipient
748 -1 if not previously had a good recipient
749 inblock incoming SMTP block
750 timeout timeout value
751 buffer buffer for reading response
752 buffsize size of buffer
753
754 Returns: 3 if at least one address had 2xx and one had 5xx
755 2 if at least one address had 5xx but none had 2xx
756 1 if at least one host had a 2xx response, but none had 5xx
757 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
758 -1 timeout while reading RCPT response
759 -2 I/O or other non-response error for RCPT
760 -3 DATA or MAIL failed - errno and buffer set
761 */
762
763 static int
764 sync_responses(address_item *addrlist, BOOL include_affixes,
765 address_item **sync_addr, host_item *host, int count,
766 BOOL address_retry_include_sender, BOOL pending_MAIL,
767 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
768 int buffsize)
769 {
770 address_item *addr = *sync_addr;
771 int yield = 0;
772
773 /* Handle the response for a MAIL command. On error, reinstate the original
774 command in big_buffer for error message use, and flush any further pending
775 responses before returning, except after I/O errors and timeouts. */
776
777 if (pending_MAIL)
778 {
779 count--;
780 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
781 {
782 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
783 if (errno == 0 && buffer[0] != 0)
784 {
785 uschar flushbuffer[4096];
786 int save_errno = 0;
787 if (buffer[0] == '4')
788 {
789 save_errno = ERRNO_MAIL4XX;
790 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
791 }
792 while (count-- > 0)
793 {
794 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
795 '2', timeout)
796 && (errno != 0 || flushbuffer[0] == 0))
797 break;
798 }
799 errno = save_errno;
800 }
801
802 if (pending_DATA) count--; /* Number of RCPT responses to come */
803 while (count-- > 0) /* Mark any pending addrs with the host used */
804 {
805 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
806 addr->host_used = host;
807 addr = addr->next;
808 }
809 return -3;
810 }
811 }
812
813 if (pending_DATA) count--; /* Number of RCPT responses to come */
814
815 /* Read and handle the required number of RCPT responses, matching each one up
816 with an address by scanning for the next address whose status is PENDING_DEFER.
817 */
818
819 while (count-- > 0)
820 {
821 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
822
823 /* The address was accepted */
824 addr->host_used = host;
825
826 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
827 {
828 yield |= 1;
829 addr->transport_return = PENDING_OK;
830
831 /* If af_dr_retry_exists is set, there was a routing delay on this address;
832 ensure that any address-specific retry record is expunged. We do this both
833 for the basic key and for the version that also includes the sender. */
834
835 if (testflag(addr, af_dr_retry_exists))
836 {
837 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
838 sender_address);
839 retry_add_item(addr, altkey, rf_delete);
840 retry_add_item(addr, addr->address_retry_key, rf_delete);
841 }
842 }
843
844 /* Timeout while reading the response */
845
846 else if (errno == ETIMEDOUT)
847 {
848 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
849 transport_rcpt_address(addr, include_affixes));
850 set_errno(addrlist, ETIMEDOUT, message, DEFER, FALSE, NULL);
851 retry_add_item(addr, addr->address_retry_key, 0);
852 update_waiting = FALSE;
853 return -1;
854 }
855
856 /* Handle other errors in obtaining an SMTP response by returning -1. This
857 will cause all the addresses to be deferred. Restore the SMTP command in
858 big_buffer for which we are checking the response, so the error message
859 makes sense. */
860
861 else if (errno != 0 || buffer[0] == 0)
862 {
863 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
864 transport_rcpt_address(addr, include_affixes));
865 return -2;
866 }
867
868 /* Handle SMTP permanent and temporary response codes. */
869
870 else
871 {
872 addr->message =
873 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
874 "%s", transport_rcpt_address(addr, include_affixes),
875 string_printing(buffer));
876 setflag(addr, af_pass_message);
877 msglog_line(host, addr->message);
878
879 /* The response was 5xx */
880
881 if (buffer[0] == '5')
882 {
883 addr->transport_return = FAIL;
884 yield |= 2;
885 }
886
887 /* The response was 4xx */
888
889 else
890 {
891 addr->transport_return = DEFER;
892 addr->basic_errno = ERRNO_RCPT4XX;
893 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
894
895 /* Log temporary errors if there are more hosts to be tried.
896 If not, log this last one in the == line. */
897
898 if (host->next)
899 log_write(0, LOG_MAIN, "H=%s [%s]: %s", host->name, host->address, addr->message);
900
901 /* Do not put this message on the list of those waiting for specific
902 hosts, as otherwise it is likely to be tried too often. */
903
904 update_waiting = FALSE;
905
906 /* Add a retry item for the address so that it doesn't get tried again
907 too soon. If address_retry_include_sender is true, add the sender address
908 to the retry key. */
909
910 if (address_retry_include_sender)
911 {
912 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
913 sender_address);
914 retry_add_item(addr, altkey, 0);
915 }
916 else retry_add_item(addr, addr->address_retry_key, 0);
917 }
918 }
919 } /* Loop for next RCPT response */
920
921 /* Update where to start at for the next block of responses, unless we
922 have already handled all the addresses. */
923
924 if (addr != NULL) *sync_addr = addr->next;
925
926 /* Handle a response to DATA. If we have not had any good recipients, either
927 previously or in this block, the response is ignored. */
928
929 if (pending_DATA != 0 &&
930 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
931 {
932 int code;
933 uschar *msg;
934 BOOL pass_message;
935 if (pending_DATA > 0 || (yield & 1) != 0)
936 {
937 if (errno == 0 && buffer[0] == '4')
938 {
939 errno = ERRNO_DATA4XX;
940 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
941 }
942 return -3;
943 }
944 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
945 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
946 "is in use and there were no good recipients\n", msg);
947 }
948
949 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
950 present) received 3xx. If any RCPTs were handled and yielded anything other
951 than 4xx, yield will be set non-zero. */
952
953 return yield;
954 }
955
956
957
958 /* Do the client side of smtp-level authentication */
959 /*
960 Arguments:
961 buffer EHLO response from server (gets overwritten)
962 addrlist chain of potential addresses to deliver
963 host host to deliver to
964 ob transport options
965 ibp, obp comms channel control blocks
966
967 Returns:
968 OK Success, or failed (but not required): global "smtp_authenticated" set
969 DEFER Failed authentication (and was required)
970 ERROR Internal problem
971
972 FAIL_SEND Failed communications - transmit
973 FAIL - response
974 */
975
976 int
977 smtp_auth(uschar *buffer, unsigned bufsize, address_item *addrlist, host_item *host,
978 smtp_transport_options_block *ob, BOOL is_esmtp,
979 smtp_inblock *ibp, smtp_outblock *obp)
980 {
981 int require_auth;
982 uschar *fail_reason = US"server did not advertise AUTH support";
983
984 smtp_authenticated = FALSE;
985 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
986 require_auth = verify_check_given_host(&ob->hosts_require_auth, host);
987
988 if (is_esmtp && !regex_AUTH) regex_AUTH =
989 regex_must_compile(US"\\n250[\\s\\-]AUTH\\s+([\\-\\w\\s]+)(?:\\n|$)",
990 FALSE, TRUE);
991
992 if (is_esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
993 {
994 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
995 expand_nmax = -1; /* reset */
996
997 /* Must not do this check until after we have saved the result of the
998 regex match above. */
999
1000 if (require_auth == OK ||
1001 verify_check_given_host(&ob->hosts_try_auth, host) == OK)
1002 {
1003 auth_instance *au;
1004 fail_reason = US"no common mechanisms were found";
1005
1006 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1007
1008 /* Scan the configured authenticators looking for one which is configured
1009 for use as a client, which is not suppressed by client_condition, and
1010 whose name matches an authentication mechanism supported by the server.
1011 If one is found, attempt to authenticate by calling its client function.
1012 */
1013
1014 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1015 {
1016 uschar *p = names;
1017 if (!au->client ||
1018 (au->client_condition != NULL &&
1019 !expand_check_condition(au->client_condition, au->name,
1020 US"client authenticator")))
1021 {
1022 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1023 au->name,
1024 (au->client)? "client_condition is false" :
1025 "not configured as a client");
1026 continue;
1027 }
1028
1029 /* Loop to scan supported server mechanisms */
1030
1031 while (*p != 0)
1032 {
1033 int rc;
1034 int len = Ustrlen(au->public_name);
1035 while (isspace(*p)) p++;
1036
1037 if (strncmpic(au->public_name, p, len) != 0 ||
1038 (p[len] != 0 && !isspace(p[len])))
1039 {
1040 while (*p != 0 && !isspace(*p)) p++;
1041 continue;
1042 }
1043
1044 /* Found data for a listed mechanism. Call its client entry. Set
1045 a flag in the outblock so that data is overwritten after sending so
1046 that reflections don't show it. */
1047
1048 fail_reason = US"authentication attempt(s) failed";
1049 obp->authenticating = TRUE;
1050 rc = (au->info->clientcode)(au, ibp, obp,
1051 ob->command_timeout, buffer, bufsize);
1052 obp->authenticating = FALSE;
1053 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1054 au->name, rc);
1055
1056 /* A temporary authentication failure must hold up delivery to
1057 this host. After a permanent authentication failure, we carry on
1058 to try other authentication methods. If all fail hard, try to
1059 deliver the message unauthenticated unless require_auth was set. */
1060
1061 switch(rc)
1062 {
1063 case OK:
1064 smtp_authenticated = TRUE; /* stops the outer loop */
1065 client_authenticator = au->name;
1066 if (au->set_client_id != NULL)
1067 client_authenticated_id = expand_string(au->set_client_id);
1068 break;
1069
1070 /* Failure after writing a command */
1071
1072 case FAIL_SEND:
1073 return FAIL_SEND;
1074
1075 /* Failure after reading a response */
1076
1077 case FAIL:
1078 if (errno != 0 || buffer[0] != '5') return FAIL;
1079 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1080 au->name, host->name, host->address, buffer);
1081 break;
1082
1083 /* Failure by some other means. In effect, the authenticator
1084 decided it wasn't prepared to handle this case. Typically this
1085 is the result of "fail" in an expansion string. Do we need to
1086 log anything here? Feb 2006: a message is now put in the buffer
1087 if logging is required. */
1088
1089 case CANCELLED:
1090 if (*buffer != 0)
1091 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1092 "authentication H=%s [%s] %s", au->name, host->name,
1093 host->address, buffer);
1094 break;
1095
1096 /* Internal problem, message in buffer. */
1097
1098 case ERROR:
1099 set_errno(addrlist, ERRNO_AUTHPROB, string_copy(buffer),
1100 DEFER, FALSE, NULL);
1101 return ERROR;
1102 }
1103
1104 break; /* If not authenticated, try next authenticator */
1105 } /* Loop for scanning supported server mechanisms */
1106 } /* Loop for further authenticators */
1107 }
1108 }
1109
1110 /* If we haven't authenticated, but are required to, give up. */
1111
1112 if (require_auth == OK && !smtp_authenticated)
1113 {
1114 set_errno(addrlist, ERRNO_AUTHFAIL,
1115 string_sprintf("authentication required but %s", fail_reason), DEFER,
1116 FALSE, NULL);
1117 return DEFER;
1118 }
1119
1120 return OK;
1121 }
1122
1123
1124 /* Construct AUTH appendix string for MAIL TO */
1125 /*
1126 Arguments
1127 buffer to build string
1128 addrlist chain of potential addresses to deliver
1129 ob transport options
1130
1131 Globals smtp_authenticated
1132 client_authenticated_sender
1133 Return True on error, otherwise buffer has (possibly empty) terminated string
1134 */
1135
1136 BOOL
1137 smtp_mail_auth_str(uschar *buffer, unsigned bufsize, address_item *addrlist,
1138 smtp_transport_options_block *ob)
1139 {
1140 uschar *local_authenticated_sender = authenticated_sender;
1141
1142 #ifdef notdef
1143 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n", authenticated_sender, ob->authenticated_sender, smtp_authenticated?"Y":"N");
1144 #endif
1145
1146 if (ob->authenticated_sender != NULL)
1147 {
1148 uschar *new = expand_string(ob->authenticated_sender);
1149 if (new == NULL)
1150 {
1151 if (!expand_string_forcedfail)
1152 {
1153 uschar *message = string_sprintf("failed to expand "
1154 "authenticated_sender: %s", expand_string_message);
1155 set_errno(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, NULL);
1156 return TRUE;
1157 }
1158 }
1159 else if (new[0] != 0) local_authenticated_sender = new;
1160 }
1161
1162 /* Add the authenticated sender address if present */
1163
1164 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1165 local_authenticated_sender != NULL)
1166 {
1167 string_format(buffer, bufsize, " AUTH=%s",
1168 auth_xtextencode(local_authenticated_sender,
1169 Ustrlen(local_authenticated_sender)));
1170 client_authenticated_sender = string_copy(local_authenticated_sender);
1171 }
1172 else
1173 *buffer= 0;
1174
1175 return FALSE;
1176 }
1177
1178
1179
1180 #ifdef EXPERIMENTAL_DANE
1181 int
1182 tlsa_lookup(const host_item * host, dns_answer * dnsa,
1183 BOOL dane_required, BOOL * dane)
1184 {
1185 /* move this out to host.c given the similarity to dns_lookup() ? */
1186 uschar buffer[300];
1187 const uschar * fullname = buffer;
1188
1189 /* TLSA lookup string */
1190 (void)sprintf(CS buffer, "_%d._tcp.%.256s", host->port, host->name);
1191
1192 switch (dns_lookup(dnsa, buffer, T_TLSA, &fullname))
1193 {
1194 case DNS_AGAIN:
1195 return DEFER; /* just defer this TLS'd conn */
1196
1197 default:
1198 case DNS_FAIL:
1199 if (dane_required)
1200 return FAIL;
1201 break;
1202
1203 case DNS_SUCCEED:
1204 if (!dns_is_secure(dnsa))
1205 {
1206 log_write(0, LOG_MAIN, "DANE error: TLSA lookup not DNSSEC");
1207 return DEFER;
1208 }
1209 *dane = TRUE;
1210 break;
1211 }
1212 return OK;
1213 }
1214 #endif
1215
1216
1217
1218 typedef struct smtp_compare_s
1219 {
1220 uschar *current_sender_address;
1221 struct transport_instance *tblock;
1222 } smtp_compare_t;
1223
1224 /*
1225 Create a unique string that identifies this message, it is based on
1226 sender_address, helo_data and tls_certificate if enabled. */
1227
1228 static uschar *
1229 smtp_local_identity(uschar * sender, struct transport_instance * tblock)
1230 {
1231 address_item * addr1;
1232 uschar * if1 = US"";
1233 uschar * helo1 = US"";
1234 #ifdef SUPPORT_TLS
1235 uschar * tlsc1 = US"";
1236 #endif
1237 uschar * save_sender_address = sender_address;
1238 uschar * local_identity = NULL;
1239 smtp_transport_options_block * ob =
1240 (smtp_transport_options_block *)tblock->options_block;
1241
1242 sender_address = sender;
1243
1244 addr1 = deliver_make_addr (sender, TRUE);
1245 deliver_set_expansions(addr1);
1246
1247 if (ob->interface)
1248 if1 = expand_string(ob->interface);
1249
1250 if (ob->helo_data)
1251 helo1 = expand_string(ob->helo_data);
1252
1253 #ifdef SUPPORT_TLS
1254 if (ob->tls_certificate)
1255 tlsc1 = expand_string(ob->tls_certificate);
1256 local_identity = string_sprintf ("%s^%s^%s", if1, helo1, tlsc1);
1257 #else
1258 local_identity = string_sprintf ("%s^%s", if1, helo1);
1259 #endif
1260
1261 deliver_set_expansions(NULL);
1262 sender_address = save_sender_address;
1263
1264 return local_identity;
1265 }
1266
1267
1268
1269 /* This routine is a callback that is called from transport_check_waiting.
1270 This function will evaluate the incoming message versus the previous
1271 message. If the incoming message is using a different local identity then
1272 we will veto this new message. */
1273
1274 static BOOL
1275 smtp_are_same_identities(uschar * message_id, smtp_compare_t * s_compare)
1276 {
1277 uschar * save_sender_address = sender_address;
1278 uschar * current_local_identity =
1279 smtp_local_identity(s_compare->current_sender_address, s_compare->tblock);
1280 uschar * new_sender_address = deliver_get_sender_address(message_id);
1281 uschar * message_local_identity =
1282 smtp_local_identity(new_sender_address, s_compare->tblock);
1283
1284 sender_address = save_sender_address;
1285
1286 return Ustrcmp(current_local_identity, message_local_identity) == 0;
1287 }
1288
1289
1290
1291 /*************************************************
1292 * Deliver address list to given host *
1293 *************************************************/
1294
1295 /* If continue_hostname is not null, we get here only when continuing to
1296 deliver down an existing channel. The channel was passed as the standard
1297 input. TLS is never active on a passed channel; the previous process always
1298 closes it down before passing the connection on.
1299
1300 Otherwise, we have to make a connection to the remote host, and do the
1301 initial protocol exchange.
1302
1303 When running as an MUA wrapper, if the sender or any recipient is rejected,
1304 temporarily or permanently, we force failure for all recipients.
1305
1306 Arguments:
1307 addrlist chain of potential addresses to deliver; only those whose
1308 transport_return field is set to PENDING_DEFER are currently
1309 being processed; others should be skipped - they have either
1310 been delivered to an earlier host or IP address, or been
1311 failed by one of them.
1312 host host to deliver to
1313 host_af AF_INET or AF_INET6
1314 port default TCP/IP port to use, in host byte order
1315 interface interface to bind to, or NULL
1316 tblock transport instance block
1317 message_defer set TRUE if yield is OK, but all addresses were deferred
1318 because of a non-recipient, non-host failure, that is, a
1319 4xx response to MAIL FROM, DATA, or ".". This is a defer
1320 that is specific to the message.
1321 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1322 a second attempt after TLS initialization fails
1323
1324 Returns: OK - the connection was made and the delivery attempted;
1325 the result for each address is in its data block.
1326 DEFER - the connection could not be made, or something failed
1327 while setting up the SMTP session, or there was a
1328 non-message-specific error, such as a timeout.
1329 ERROR - a filter command is specified for this transport,
1330 and there was a problem setting it up; OR helo_data
1331 or add_headers or authenticated_sender is specified
1332 for this transport, and the string failed to expand
1333 */
1334
1335 static int
1336 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
1337 uschar *interface, transport_instance *tblock,
1338 BOOL *message_defer, BOOL suppress_tls)
1339 {
1340 address_item *addr;
1341 address_item *sync_addr;
1342 address_item *first_addr = addrlist;
1343 int yield = OK;
1344 int address_count;
1345 int save_errno;
1346 int rc;
1347 time_t start_delivery_time = time(NULL);
1348 smtp_transport_options_block *ob =
1349 (smtp_transport_options_block *)(tblock->options_block);
1350 BOOL lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
1351 BOOL smtps = strcmpic(ob->protocol, US"smtps") == 0;
1352 BOOL ok = FALSE;
1353 BOOL send_rset = TRUE;
1354 BOOL send_quit = TRUE;
1355 BOOL setting_up = TRUE;
1356 BOOL completed_address = FALSE;
1357 BOOL esmtp = TRUE;
1358 BOOL pending_MAIL;
1359 BOOL pass_message = FALSE;
1360 #ifndef DISABLE_PRDR
1361 BOOL prdr_offered = FALSE;
1362 BOOL prdr_active;
1363 #endif
1364 #ifdef EXPERIMENTAL_INTERNATIONAL
1365 BOOL utf8_needed = FALSE;
1366 BOOL utf8_offered = FALSE;
1367 #endif
1368 BOOL dsn_all_lasthop = TRUE;
1369 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1370 BOOL dane = FALSE;
1371 BOOL dane_required = verify_check_given_host(&ob->hosts_require_dane, host) == OK;
1372 dns_answer tlsa_dnsa;
1373 #endif
1374 smtp_inblock inblock;
1375 smtp_outblock outblock;
1376 int max_rcpt = tblock->max_addresses;
1377 uschar *igquotstr = US"";
1378
1379 uschar *helo_data = NULL;
1380
1381 uschar *message = NULL;
1382 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
1383 uschar *p;
1384 uschar buffer[4096];
1385 uschar inbuffer[4096];
1386 uschar outbuffer[4096];
1387
1388 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
1389
1390 *message_defer = FALSE;
1391 smtp_command = US"initial connection";
1392 if (max_rcpt == 0) max_rcpt = 999999;
1393
1394 /* Set up the buffer for reading SMTP response packets. */
1395
1396 inblock.buffer = inbuffer;
1397 inblock.buffersize = sizeof(inbuffer);
1398 inblock.ptr = inbuffer;
1399 inblock.ptrend = inbuffer;
1400
1401 /* Set up the buffer for holding SMTP commands while pipelining */
1402
1403 outblock.buffer = outbuffer;
1404 outblock.buffersize = sizeof(outbuffer);
1405 outblock.ptr = outbuffer;
1406 outblock.cmd_count = 0;
1407 outblock.authenticating = FALSE;
1408
1409 /* Reset the parameters of a TLS session. */
1410
1411 tls_out.bits = 0;
1412 tls_out.cipher = NULL; /* the one we may use for this transport */
1413 tls_out.ourcert = NULL;
1414 tls_out.peercert = NULL;
1415 tls_out.peerdn = NULL;
1416 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1417 tls_out.sni = NULL;
1418 #endif
1419 tls_out.ocsp = OCSP_NOT_REQ;
1420
1421 /* Flip the legacy TLS-related variables over to the outbound set in case
1422 they're used in the context of the transport. Don't bother resetting
1423 afterward as we're in a subprocess. */
1424
1425 tls_modify_variables(&tls_out);
1426
1427 #ifndef SUPPORT_TLS
1428 if (smtps)
1429 {
1430 set_errno(addrlist, ERRNO_TLSFAILURE, US"TLS support not available",
1431 DEFER, FALSE, NULL);
1432 return ERROR;
1433 }
1434 #endif
1435
1436 /* Make a connection to the host if this isn't a continued delivery, and handle
1437 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
1438 specially so they can be identified for retries. */
1439
1440 if (continue_hostname == NULL)
1441 {
1442 /* This puts port into host->port */
1443 inblock.sock = outblock.sock =
1444 smtp_connect(host, host_af, port, interface, ob->connect_timeout, tblock);
1445
1446 if (inblock.sock < 0)
1447 {
1448 set_errno(addrlist, (errno == ETIMEDOUT)? ERRNO_CONNECTTIMEOUT : errno,
1449 NULL, DEFER, FALSE, NULL);
1450 return DEFER;
1451 }
1452
1453 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1454 {
1455 tls_out.dane_verified = FALSE;
1456 tls_out.tlsa_usage = 0;
1457
1458 if (host->dnssec == DS_YES)
1459 {
1460 if( ( dane_required
1461 || verify_check_given_host(&ob->hosts_try_dane, host) == OK
1462 )
1463 && (rc = tlsa_lookup(host, &tlsa_dnsa, dane_required, &dane)) != OK
1464 && dane_required /* do not error on only dane-requested */
1465 )
1466 {
1467 set_errno(addrlist, ERRNO_DNSDEFER,
1468 string_sprintf("DANE error: tlsa lookup %s",
1469 rc == DEFER ? "DEFER" : "FAIL"),
1470 rc, FALSE, NULL);
1471 return rc;
1472 }
1473 }
1474 else if (dane_required)
1475 {
1476 set_errno(addrlist, ERRNO_DNSDEFER,
1477 string_sprintf("DANE error: %s lookup not DNSSEC", host->name),
1478 FAIL, FALSE, NULL);
1479 return FAIL;
1480 }
1481
1482 if (dane)
1483 ob->tls_tempfail_tryclear = FALSE;
1484 }
1485 #endif /*DANE*/
1486
1487 /* Expand the greeting message while waiting for the initial response. (Makes
1488 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1489 delayed till here so that $sending_interface and $sending_port are set. */
1490
1491 helo_data = expand_string(ob->helo_data);
1492 #ifdef EXPERIMENTAL_INTERNATIONAL
1493 if (helo_data)
1494 {
1495 uschar * errstr = NULL;
1496 if ((helo_data = string_domain_utf8_to_alabel(helo_data, &errstr)), errstr)
1497 {
1498 errstr = string_sprintf("failed to expand helo_data: %s", errstr);
1499 set_errno(addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE, NULL);
1500 yield = DEFER;
1501 goto SEND_QUIT;
1502 }
1503 }
1504 #endif
1505
1506 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1507 is nevertheless a reasonably clean way of programming this kind of logic,
1508 where you want to escape on any error. */
1509
1510 if (!smtps)
1511 {
1512 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1513 ob->command_timeout)) goto RESPONSE_FAILED;
1514
1515 #ifdef EXPERIMENTAL_EVENT
1516 {
1517 uschar * s;
1518 lookup_dnssec_authenticated = host->dnssec==DS_YES ? US"yes"
1519 : host->dnssec==DS_NO ? US"no" : NULL;
1520 s = event_raise(tblock->event_action, US"smtp:connect", buffer);
1521 if (s)
1522 {
1523 set_errno(addrlist, ERRNO_EXPANDFAIL,
1524 string_sprintf("deferred by smtp:connect event expansion: %s", s),
1525 DEFER, FALSE, NULL);
1526 yield = DEFER;
1527 goto SEND_QUIT;
1528 }
1529 }
1530 #endif
1531
1532 /* Now check if the helo_data expansion went well, and sign off cleanly if
1533 it didn't. */
1534
1535 if (helo_data == NULL)
1536 {
1537 uschar *message = string_sprintf("failed to expand helo_data: %s",
1538 expand_string_message);
1539 set_errno(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, NULL);
1540 yield = DEFER;
1541 goto SEND_QUIT;
1542 }
1543 }
1544
1545 /** Debugging without sending a message
1546 addrlist->transport_return = DEFER;
1547 goto SEND_QUIT;
1548 **/
1549
1550 /* Errors that occur after this point follow an SMTP command, which is
1551 left in big_buffer by smtp_write_command() for use in error messages. */
1552
1553 smtp_command = big_buffer;
1554
1555 /* Tell the remote who we are...
1556
1557 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1558 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1559 greeting is of this form. The assumption was that the far end supports it
1560 properly... but experience shows that there are some that give 5xx responses,
1561 even though the banner includes "ESMTP" (there's a bloody-minded one that
1562 says "ESMTP not spoken here"). Cope with that case.
1563
1564 September 2000: Time has passed, and it seems reasonable now to always send
1565 EHLO at the start. It is also convenient to make the change while installing
1566 the TLS stuff.
1567
1568 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1569 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1570 would be no way to send out the mails, so there is now a host list
1571 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1572 PIPELINING problem as well. Maybe it can also be useful to cure other
1573 problems with broken servers.
1574
1575 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1576 Then somebody tried it with a Microsoft mailer... It seems that all other
1577 mailers use upper case for some reason (the RFC is quite clear about case
1578 independence) so, for peace of mind, I gave in. */
1579
1580 esmtp = verify_check_given_host(&ob->hosts_avoid_esmtp, host) != OK;
1581
1582 /* Alas; be careful, since this goto is not an error-out, so conceivably
1583 we might set data between here and the target which we assume to exist
1584 and be usable. I can see this coming back to bite us. */
1585 #ifdef SUPPORT_TLS
1586 if (smtps)
1587 {
1588 tls_offered = TRUE;
1589 suppress_tls = FALSE;
1590 ob->tls_tempfail_tryclear = FALSE;
1591 smtp_command = US"SSL-on-connect";
1592 goto TLS_NEGOTIATE;
1593 }
1594 #endif
1595
1596 if (esmtp)
1597 {
1598 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1599 lmtp? "LHLO" : "EHLO", helo_data) < 0)
1600 goto SEND_FAILED;
1601 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1602 ob->command_timeout))
1603 {
1604 if (errno != 0 || buffer[0] == 0 || lmtp) goto RESPONSE_FAILED;
1605 esmtp = FALSE;
1606 }
1607 }
1608 else
1609 {
1610 DEBUG(D_transport)
1611 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1612 }
1613
1614 if (!esmtp)
1615 {
1616 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1617 goto SEND_FAILED;
1618 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1619 ob->command_timeout)) goto RESPONSE_FAILED;
1620 }
1621
1622 /* Set IGNOREQUOTA if the response to LHLO specifies support and the
1623 lmtp_ignore_quota option was set. */
1624
1625 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1626 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1627 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1628
1629 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1630
1631 #ifdef SUPPORT_TLS
1632 tls_offered = esmtp &&
1633 pcre_exec(regex_STARTTLS, NULL, CS buffer, Ustrlen(buffer), 0,
1634 PCRE_EOPT, NULL, 0) >= 0;
1635 #endif
1636
1637 #ifndef DISABLE_PRDR
1638 prdr_offered = esmtp
1639 && pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(buffer), 0,
1640 PCRE_EOPT, NULL, 0) >= 0
1641 && verify_check_given_host(&ob->hosts_try_prdr, host) == OK;
1642
1643 if (prdr_offered)
1644 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1645 #endif
1646
1647 #ifdef EXPERIMENTAL_INTERNATIONAL
1648 if (addrlist->prop.utf8_msg)
1649 {
1650 utf8_needed = !addrlist->prop.utf8_downcvt
1651 && !addrlist->prop.utf8_downcvt_maybe;
1652 DEBUG(D_transport) if (!utf8_needed) debug_printf("utf8: %s downconvert\n",
1653 addrlist->prop.utf8_downcvt ? "mandatory" : "optional");
1654
1655 utf8_offered = esmtp
1656 && pcre_exec(regex_UTF8, NULL, CS buffer, Ustrlen(buffer), 0,
1657 PCRE_EOPT, NULL, 0) >= 0;
1658 }
1659 #endif
1660 }
1661
1662 /* For continuing deliveries down the same channel, the socket is the standard
1663 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1664 below). Set up the pointer to where subsequent commands will be left, for
1665 error messages. Note that smtp_use_size and smtp_use_pipelining will have been
1666 set from the command line if they were set in the process that passed the
1667 connection on. */
1668
1669 else
1670 {
1671 inblock.sock = outblock.sock = fileno(stdin);
1672 smtp_command = big_buffer;
1673 host->port = port; /* Record the port that was used */
1674 }
1675
1676 /* If TLS is available on this connection, whether continued or not, attempt to
1677 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1678 send another EHLO - the server may give a different answer in secure mode. We
1679 use a separate buffer for reading the response to STARTTLS so that if it is
1680 negative, the original EHLO data is available for subsequent analysis, should
1681 the client not be required to use TLS. If the response is bad, copy the buffer
1682 for error analysis. */
1683
1684 #ifdef SUPPORT_TLS
1685 if ( tls_offered
1686 && !suppress_tls
1687 && verify_check_given_host(&ob->hosts_avoid_tls, host) != OK)
1688 {
1689 uschar buffer2[4096];
1690 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1691 goto SEND_FAILED;
1692
1693 /* If there is an I/O error, transmission of this message is deferred. If
1694 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1695 false, we also defer. However, if there is a temporary rejection of STARTTLS
1696 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1697 STARTTLS, we carry on. This means we will try to send the message in clear,
1698 unless the host is in hosts_require_tls (tested below). */
1699
1700 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1701 ob->command_timeout))
1702 {
1703 if (errno != 0 || buffer2[0] == 0 ||
1704 (buffer2[0] == '4' && !ob->tls_tempfail_tryclear))
1705 {
1706 Ustrncpy(buffer, buffer2, sizeof(buffer));
1707 goto RESPONSE_FAILED;
1708 }
1709 }
1710
1711 /* STARTTLS accepted: try to negotiate a TLS session. */
1712
1713 else
1714 TLS_NEGOTIATE:
1715 {
1716 int rc = tls_client_start(inblock.sock, host, addrlist, tblock
1717 # ifdef EXPERIMENTAL_DANE
1718 , dane ? &tlsa_dnsa : NULL
1719 # endif
1720 );
1721
1722 /* TLS negotiation failed; give an error. From outside, this function may
1723 be called again to try in clear on a new connection, if the options permit
1724 it for this host. */
1725
1726 if (rc != OK)
1727 {
1728 # ifdef EXPERIMENTAL_DANE
1729 if (rc == DEFER && dane && !dane_required)
1730 {
1731 log_write(0, LOG_MAIN, "DANE attempt failed;"
1732 " trying CA-root TLS to %s [%s] (not in hosts_require_dane)",
1733 host->name, host->address);
1734 dane = FALSE;
1735 goto TLS_NEGOTIATE;
1736 }
1737 # endif
1738
1739 save_errno = ERRNO_TLSFAILURE;
1740 message = US"failure while setting up TLS session";
1741 send_quit = FALSE;
1742 goto TLS_FAILED;
1743 }
1744
1745 /* TLS session is set up */
1746
1747 for (addr = addrlist; addr != NULL; addr = addr->next)
1748 if (addr->transport_return == PENDING_DEFER)
1749 {
1750 addr->cipher = tls_out.cipher;
1751 addr->ourcert = tls_out.ourcert;
1752 addr->peercert = tls_out.peercert;
1753 addr->peerdn = tls_out.peerdn;
1754 addr->ocsp = tls_out.ocsp;
1755 }
1756 }
1757 }
1758
1759 /* if smtps, we'll have smtp_command set to something else; always safe to
1760 reset it here. */
1761 smtp_command = big_buffer;
1762
1763 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1764 helo_data is null, we are dealing with a connection that was passed from
1765 another process, and so we won't have expanded helo_data above. We have to
1766 expand it here. $sending_ip_address and $sending_port are set up right at the
1767 start of the Exim process (in exim.c). */
1768
1769 if (tls_out.active >= 0)
1770 {
1771 char *greeting_cmd;
1772 if (helo_data == NULL)
1773 {
1774 helo_data = expand_string(ob->helo_data);
1775 if (helo_data == NULL)
1776 {
1777 uschar *message = string_sprintf("failed to expand helo_data: %s",
1778 expand_string_message);
1779 set_errno(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, NULL);
1780 yield = DEFER;
1781 goto SEND_QUIT;
1782 }
1783 }
1784
1785 /* For SMTPS we need to wait for the initial OK response. */
1786 if (smtps)
1787 {
1788 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1789 ob->command_timeout)) goto RESPONSE_FAILED;
1790 }
1791
1792 if (esmtp)
1793 greeting_cmd = "EHLO";
1794 else
1795 {
1796 greeting_cmd = "HELO";
1797 DEBUG(D_transport)
1798 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1799 }
1800
1801 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1802 lmtp? "LHLO" : greeting_cmd, helo_data) < 0)
1803 goto SEND_FAILED;
1804 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1805 ob->command_timeout))
1806 goto RESPONSE_FAILED;
1807 }
1808
1809 /* If the host is required to use a secure channel, ensure that we
1810 have one. */
1811
1812 else if (
1813 # ifdef EXPERIMENTAL_DANE
1814 dane ||
1815 # endif
1816 verify_check_given_host(&ob->hosts_require_tls, host) == OK
1817 )
1818 {
1819 save_errno = ERRNO_TLSREQUIRED;
1820 message = string_sprintf("a TLS session is required, but %s",
1821 tls_offered? "an attempt to start TLS failed" :
1822 "the server did not offer TLS support");
1823 goto TLS_FAILED;
1824 }
1825 #endif /*SUPPORT_TLS*/
1826
1827 /* If TLS is active, we have just started it up and re-done the EHLO command,
1828 so its response needs to be analyzed. If TLS is not active and this is a
1829 continued session down a previously-used socket, we haven't just done EHLO, so
1830 we skip this. */
1831
1832 if (continue_hostname == NULL
1833 #ifdef SUPPORT_TLS
1834 || tls_out.active >= 0
1835 #endif
1836 )
1837 {
1838 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
1839 lmtp_ignore_quota option was set. */
1840
1841 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1842 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1843 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1844
1845 /* If the response to EHLO specified support for the SIZE parameter, note
1846 this, provided size_addition is non-negative. */
1847
1848 smtp_use_size = esmtp && ob->size_addition >= 0 &&
1849 pcre_exec(regex_SIZE, NULL, CS buffer, Ustrlen(CS buffer), 0,
1850 PCRE_EOPT, NULL, 0) >= 0;
1851
1852 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
1853 the current host, esmtp will be false, so PIPELINING can never be used. If
1854 the current host matches hosts_avoid_pipelining, don't do it. */
1855
1856 smtp_use_pipelining = esmtp
1857 && verify_check_given_host(&ob->hosts_avoid_pipelining, host) != OK
1858 && pcre_exec(regex_PIPELINING, NULL, CS buffer, Ustrlen(CS buffer), 0,
1859 PCRE_EOPT, NULL, 0) >= 0;
1860
1861 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
1862 smtp_use_pipelining? "" : "not ");
1863
1864 #ifndef DISABLE_PRDR
1865 prdr_offered = esmtp
1866 && pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(CS buffer), 0,
1867 PCRE_EOPT, NULL, 0) >= 0
1868 && verify_check_given_host(&ob->hosts_try_prdr, host) == OK;
1869
1870 if (prdr_offered)
1871 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1872 #endif
1873
1874 #ifdef EXPERIMENTAL_INTERNATIONAL
1875 if (addrlist->prop.utf8_msg)
1876 utf8_offered = esmtp
1877 && pcre_exec(regex_UTF8, NULL, CS buffer, Ustrlen(buffer), 0,
1878 PCRE_EOPT, NULL, 0) >= 0;
1879 #endif
1880
1881 /* Note if the server supports DSN */
1882 smtp_use_dsn = esmtp
1883 && pcre_exec(regex_DSN, NULL, CS buffer, Ustrlen(CS buffer), 0,
1884 PCRE_EOPT, NULL, 0) >= 0;
1885 DEBUG(D_transport) debug_printf("use_dsn=%d\n", smtp_use_dsn);
1886
1887 /* Note if the response to EHLO specifies support for the AUTH extension.
1888 If it has, check that this host is one we want to authenticate to, and do
1889 the business. The host name and address must be available when the
1890 authenticator's client driver is running. */
1891
1892 switch (yield = smtp_auth(buffer, sizeof(buffer), addrlist, host,
1893 ob, esmtp, &inblock, &outblock))
1894 {
1895 default: goto SEND_QUIT;
1896 case OK: break;
1897 case FAIL_SEND: goto SEND_FAILED;
1898 case FAIL: goto RESPONSE_FAILED;
1899 }
1900 }
1901
1902 /* The setting up of the SMTP call is now complete. Any subsequent errors are
1903 message-specific. */
1904
1905 setting_up = FALSE;
1906
1907 #ifdef EXPERIMENTAL_INTERNATIONAL
1908 /* If this is an international message we need the host to speak SMTPUTF8 */
1909 if (utf8_needed && !utf8_offered)
1910 {
1911 errno = ERRNO_UTF8_FWD;
1912 goto RESPONSE_FAILED;
1913 }
1914 #endif
1915
1916 /* If there is a filter command specified for this transport, we can now
1917 set it up. This cannot be done until the identify of the host is known. */
1918
1919 if (tblock->filter_command != NULL)
1920 {
1921 BOOL rc;
1922 uschar buffer[64];
1923 sprintf(CS buffer, "%.50s transport", tblock->name);
1924 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
1925 TRUE, DEFER, addrlist, buffer, NULL);
1926 transport_filter_timeout = tblock->filter_timeout;
1927
1928 /* On failure, copy the error to all addresses, abandon the SMTP call, and
1929 yield ERROR. */
1930
1931 if (!rc)
1932 {
1933 set_errno(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
1934 FALSE, NULL);
1935 yield = ERROR;
1936 goto SEND_QUIT;
1937 }
1938 }
1939
1940
1941 /* For messages that have more than the maximum number of envelope recipients,
1942 we want to send several transactions down the same SMTP connection. (See
1943 comments in deliver.c as to how this reconciles, heuristically, with
1944 remote_max_parallel.) This optimization was added to Exim after the following
1945 code was already working. The simplest way to put it in without disturbing the
1946 code was to use a goto to jump back to this point when there is another
1947 transaction to handle. */
1948
1949 SEND_MESSAGE:
1950 sync_addr = first_addr;
1951 address_count = 0;
1952 ok = FALSE;
1953 send_rset = TRUE;
1954 completed_address = FALSE;
1955
1956
1957 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
1958 qualification, send it, adding something to the message size to allow for
1959 imprecision and things that get added en route. Exim keeps the number of lines
1960 in a message, so we can give an accurate value for the original message, but we
1961 need some additional to handle added headers. (Double "." characters don't get
1962 included in the count.) */
1963
1964 p = buffer;
1965 *p = 0;
1966
1967 if (smtp_use_size)
1968 {
1969 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
1970 while (*p) p++;
1971 }
1972
1973 #ifndef DISABLE_PRDR
1974 prdr_active = FALSE;
1975 if (prdr_offered)
1976 {
1977 for (addr = first_addr; addr; addr = addr->next)
1978 if (addr->transport_return == PENDING_DEFER)
1979 {
1980 for (addr = addr->next; addr; addr = addr->next)
1981 if (addr->transport_return == PENDING_DEFER)
1982 { /* at least two recipients to send */
1983 prdr_active = TRUE;
1984 sprintf(CS p, " PRDR"); p += 5;
1985 break;
1986 }
1987 break;
1988 }
1989 }
1990 #endif
1991
1992 #ifdef EXPERIMENTAL_INTERNATIONAL
1993 if (addrlist->prop.utf8_msg && !addrlist->prop.utf8_downcvt && utf8_offered)
1994 sprintf(CS p, " SMTPUTF8"), p += 9;
1995 #endif
1996
1997 /* check if all addresses have lasthop flag */
1998 /* do not send RET and ENVID if true */
1999 for (dsn_all_lasthop = TRUE, addr = first_addr;
2000 address_count < max_rcpt && addr != NULL;
2001 addr = addr->next)
2002 if ((addr->dsn_flags & rf_dsnlasthop) != 1)
2003 {
2004 dsn_all_lasthop = FALSE;
2005 break;
2006 }
2007
2008 /* Add any DSN flags to the mail command */
2009
2010 if (smtp_use_dsn && !dsn_all_lasthop)
2011 {
2012 if (dsn_ret == dsn_ret_hdrs)
2013 {
2014 Ustrcpy(p, " RET=HDRS");
2015 while (*p) p++;
2016 }
2017 else if (dsn_ret == dsn_ret_full)
2018 {
2019 Ustrcpy(p, " RET=FULL");
2020 while (*p) p++;
2021 }
2022 if (dsn_envid != NULL)
2023 {
2024 string_format(p, sizeof(buffer) - (p-buffer), " ENVID=%s", dsn_envid);
2025 while (*p) p++;
2026 }
2027 }
2028
2029 /* If an authenticated_sender override has been specified for this transport
2030 instance, expand it. If the expansion is forced to fail, and there was already
2031 an authenticated_sender for this message, the original value will be used.
2032 Other expansion failures are serious. An empty result is ignored, but there is
2033 otherwise no check - this feature is expected to be used with LMTP and other
2034 cases where non-standard addresses (e.g. without domains) might be required. */
2035
2036 if (smtp_mail_auth_str(p, sizeof(buffer) - (p-buffer), addrlist, ob))
2037 {
2038 yield = ERROR;
2039 goto SEND_QUIT;
2040 }
2041
2042 /* From here until we send the DATA command, we can make use of PIPELINING
2043 if the server host supports it. The code has to be able to check the responses
2044 at any point, for when the buffer fills up, so we write it totally generally.
2045 When PIPELINING is off, each command written reports that it has flushed the
2046 buffer. */
2047
2048 pending_MAIL = TRUE; /* The block starts with MAIL */
2049
2050 {
2051 uschar * s = return_path;
2052 #ifdef EXPERIMENTAL_INTERNATIONAL
2053 uschar * errstr = NULL;
2054
2055 /* If we must downconvert, do the from-address here. Remember we had to
2056 for the to-addresses (done below), and also (ugly) for re-doing when building
2057 the delivery log line. */
2058
2059 if (addrlist->prop.utf8_msg && (addrlist->prop.utf8_downcvt || !utf8_offered))
2060 {
2061 if (s = string_address_utf8_to_alabel(return_path, &errstr), errstr)
2062 {
2063 set_errno(addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE, NULL);
2064 yield = ERROR;
2065 goto SEND_QUIT;
2066 }
2067 setflag(addrlist, af_utf8_downcvt);
2068 }
2069 #endif
2070
2071 rc = smtp_write_command(&outblock, smtp_use_pipelining,
2072 "MAIL FROM:<%s>%s\r\n", s, buffer);
2073 }
2074
2075 mail_command = string_copy(big_buffer); /* Save for later error message */
2076
2077 switch(rc)
2078 {
2079 case -1: /* Transmission error */
2080 goto SEND_FAILED;
2081
2082 case +1: /* Block was sent */
2083 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2084 ob->command_timeout))
2085 {
2086 if (errno == 0 && buffer[0] == '4')
2087 {
2088 errno = ERRNO_MAIL4XX;
2089 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2090 }
2091 goto RESPONSE_FAILED;
2092 }
2093 pending_MAIL = FALSE;
2094 break;
2095 }
2096
2097 /* Pass over all the relevant recipient addresses for this host, which are the
2098 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
2099 several before we have to read the responses for those seen so far. This
2100 checking is done by a subroutine because it also needs to be done at the end.
2101 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
2102 the next one if not all are sent.
2103
2104 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
2105 last address because we want to abort if any recipients have any kind of
2106 problem, temporary or permanent. We know that all recipient addresses will have
2107 the PENDING_DEFER status, because only one attempt is ever made, and we know
2108 that max_rcpt will be large, so all addresses will be done at once. */
2109
2110 for (addr = first_addr;
2111 address_count < max_rcpt && addr != NULL;
2112 addr = addr->next)
2113 {
2114 int count;
2115 BOOL no_flush;
2116 uschar * rcpt_addr;
2117
2118 addr->dsn_aware = smtp_use_dsn ? dsn_support_yes : dsn_support_no;
2119
2120 if (addr->transport_return != PENDING_DEFER) continue;
2121
2122 address_count++;
2123 no_flush = smtp_use_pipelining && (!mua_wrapper || addr->next != NULL);
2124
2125 /* Add any DSN flags to the rcpt command and add to the sent string */
2126
2127 p = buffer;
2128 *p = 0;
2129
2130 if (smtp_use_dsn && (addr->dsn_flags & rf_dsnlasthop) != 1)
2131 {
2132 if ((addr->dsn_flags & rf_dsnflags) != 0)
2133 {
2134 int i;
2135 BOOL first = TRUE;
2136 Ustrcpy(p, " NOTIFY=");
2137 while (*p) p++;
2138 for (i = 0; i < 4; i++)
2139 if ((addr->dsn_flags & rf_list[i]) != 0)
2140 {
2141 if (!first) *p++ = ',';
2142 first = FALSE;
2143 Ustrcpy(p, rf_names[i]);
2144 while (*p) p++;
2145 }
2146 }
2147
2148 if (addr->dsn_orcpt != NULL)
2149 {
2150 string_format(p, sizeof(buffer) - (p-buffer), " ORCPT=%s",
2151 addr->dsn_orcpt);
2152 while (*p) p++;
2153 }
2154 }
2155
2156 /* Now send the RCPT command, and process outstanding responses when
2157 necessary. After a timeout on RCPT, we just end the function, leaving the
2158 yield as OK, because this error can often mean that there is a problem with
2159 just one address, so we don't want to delay the host. */
2160
2161 rcpt_addr = transport_rcpt_address(addr, tblock->rcpt_include_affixes);
2162
2163 #ifdef EXPERIMENTAL_INTERNATIONAL
2164 {
2165 uschar * dummy_errstr;
2166 if ( testflag(addrlist, af_utf8_downcvt)
2167 && (rcpt_addr = string_address_utf8_to_alabel(rcpt_addr, &dummy_errstr),
2168 dummy_errstr
2169 ) )
2170 {
2171 errno = ERRNO_EXPANDFAIL;
2172 goto SEND_FAILED;
2173 }
2174 }
2175 #endif
2176
2177 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s%s\r\n",
2178 rcpt_addr, igquotstr, buffer);
2179
2180 if (count < 0) goto SEND_FAILED;
2181 if (count > 0)
2182 {
2183 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
2184 &sync_addr, host, count, ob->address_retry_include_sender,
2185 pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
2186 sizeof(buffer)))
2187 {
2188 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2189 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2190 break;
2191
2192 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2193 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2194 case 0: /* No 2xx or 5xx, but no probs */
2195 break;
2196
2197 case -1: goto END_OFF; /* Timeout on RCPT */
2198 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
2199 }
2200 pending_MAIL = FALSE; /* Dealt with MAIL */
2201 }
2202 } /* Loop for next address */
2203
2204 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
2205 permanently or temporarily. We should have flushed and synced after the last
2206 RCPT. */
2207
2208 if (mua_wrapper)
2209 {
2210 address_item *badaddr;
2211 for (badaddr = first_addr; badaddr; badaddr = badaddr->next)
2212 if (badaddr->transport_return != PENDING_OK)
2213 {
2214 /*XXX could we find a better errno than 0 here? */
2215 set_errno(addrlist, 0, badaddr->message, FAIL,
2216 testflag(badaddr, af_pass_message), NULL);
2217 ok = FALSE;
2218 break;
2219 }
2220 }
2221
2222 /* If ok is TRUE, we know we have got at least one good recipient, and must now
2223 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
2224 have a good recipient buffered up if we are pipelining. We don't want to waste
2225 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
2226 are pipelining. The responses are all handled by sync_responses(). */
2227
2228 if (ok || (smtp_use_pipelining && !mua_wrapper))
2229 {
2230 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
2231 if (count < 0) goto SEND_FAILED;
2232 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
2233 host, count, ob->address_retry_include_sender, pending_MAIL,
2234 ok? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
2235 {
2236 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2237 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2238 break;
2239
2240 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2241 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2242 case 0: break; /* No 2xx or 5xx, but no probs */
2243
2244 case -1: goto END_OFF; /* Timeout on RCPT */
2245 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2246 }
2247 }
2248
2249 /* Save the first address of the next batch. */
2250
2251 first_addr = addr;
2252
2253 /* If there were no good recipients (but otherwise there have been no
2254 problems), just set ok TRUE, since we have handled address-specific errors
2255 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
2256 for handling the SMTP dot-handling protocol, flagging to apply to headers as
2257 well as body. Set the appropriate timeout value to be used for each chunk.
2258 (Haven't been able to make it work using select() for writing yet.) */
2259
2260 if (!ok) ok = TRUE; else
2261 {
2262 sigalrm_seen = FALSE;
2263 transport_write_timeout = ob->data_timeout;
2264 smtp_command = US"sending data block"; /* For error messages */
2265 DEBUG(D_transport|D_v)
2266 debug_printf(" SMTP>> writing message and terminating \".\"\n");
2267 transport_count = 0;
2268
2269 #ifndef DISABLE_DKIM
2270 ok = dkim_transport_write_message(addrlist, inblock.sock,
2271 topt_use_crlf | topt_end_dot | topt_escape_headers |
2272 (tblock->body_only? topt_no_headers : 0) |
2273 (tblock->headers_only? topt_no_body : 0) |
2274 (tblock->return_path_add? topt_add_return_path : 0) |
2275 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
2276 (tblock->envelope_to_add? topt_add_envelope_to : 0),
2277 0, /* No size limit */
2278 tblock->add_headers, tblock->remove_headers,
2279 US".", US"..", /* Escaping strings */
2280 tblock->rewrite_rules, tblock->rewrite_existflags,
2281 ob->dkim_private_key, ob->dkim_domain, ob->dkim_selector,
2282 ob->dkim_canon, ob->dkim_strict, ob->dkim_sign_headers
2283 );
2284 #else
2285 ok = transport_write_message(addrlist, inblock.sock,
2286 topt_use_crlf | topt_end_dot | topt_escape_headers |
2287 (tblock->body_only? topt_no_headers : 0) |
2288 (tblock->headers_only? topt_no_body : 0) |
2289 (tblock->return_path_add? topt_add_return_path : 0) |
2290 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
2291 (tblock->envelope_to_add? topt_add_envelope_to : 0),
2292 0, /* No size limit */
2293 tblock->add_headers, tblock->remove_headers,
2294 US".", US"..", /* Escaping strings */
2295 tblock->rewrite_rules, tblock->rewrite_existflags);
2296 #endif
2297
2298 /* transport_write_message() uses write() because it is called from other
2299 places to write to non-sockets. This means that under some OS (e.g. Solaris)
2300 it can exit with "Broken pipe" as its error. This really means that the
2301 socket got closed at the far end. */
2302
2303 transport_write_timeout = 0; /* for subsequent transports */
2304
2305 /* Failure can either be some kind of I/O disaster (including timeout),
2306 or the failure of a transport filter or the expansion of added headers. */
2307
2308 if (!ok)
2309 {
2310 buffer[0] = 0; /* There hasn't been a response */
2311 goto RESPONSE_FAILED;
2312 }
2313
2314 /* We used to send the terminating "." explicitly here, but because of
2315 buffering effects at both ends of TCP/IP connections, you don't gain
2316 anything by keeping it separate, so it might as well go in the final
2317 data buffer for efficiency. This is now done by setting the topt_end_dot
2318 flag above. */
2319
2320 smtp_command = US"end of data";
2321
2322 #ifndef DISABLE_PRDR
2323 /* For PRDR we optionally get a partial-responses warning
2324 * followed by the individual responses, before going on with
2325 * the overall response. If we don't get the warning then deal
2326 * with per non-PRDR. */
2327 if(prdr_active)
2328 {
2329 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '3',
2330 ob->final_timeout);
2331 if (!ok && errno == 0)
2332 switch(buffer[0])
2333 {
2334 case '2': prdr_active = FALSE;
2335 ok = TRUE;
2336 break;
2337 case '4': errno = ERRNO_DATA4XX;
2338 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2339 break;
2340 }
2341 }
2342 else
2343 #endif
2344
2345 /* For non-PRDR SMTP, we now read a single response that applies to the
2346 whole message. If it is OK, then all the addresses have been delivered. */
2347
2348 if (!lmtp)
2349 {
2350 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2351 ob->final_timeout);
2352 if (!ok && errno == 0 && buffer[0] == '4')
2353 {
2354 errno = ERRNO_DATA4XX;
2355 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2356 }
2357 }
2358
2359 /* For LMTP, we get back a response for every RCPT command that we sent;
2360 some may be accepted and some rejected. For those that get a response, their
2361 status is fixed; any that are accepted have been handed over, even if later
2362 responses crash - at least, that's how I read RFC 2033.
2363
2364 If all went well, mark the recipient addresses as completed, record which
2365 host/IPaddress they were delivered to, and cut out RSET when sending another
2366 message down the same channel. Write the completed addresses to the journal
2367 now so that they are recorded in case there is a crash of hardware or
2368 software before the spool gets updated. Also record the final SMTP
2369 confirmation if needed (for SMTP only). */
2370
2371 if (ok)
2372 {
2373 int flag = '=';
2374 int delivery_time = (int)(time(NULL) - start_delivery_time);
2375 int len;
2376 uschar *conf = NULL;
2377 send_rset = FALSE;
2378
2379 /* Set up confirmation if needed - applies only to SMTP */
2380
2381 if (
2382 #ifndef EXPERIMENTAL_EVENT
2383 (log_extra_selector & LX_smtp_confirmation) != 0 &&
2384 #endif
2385 !lmtp
2386 )
2387 {
2388 const uschar *s = string_printing(buffer);
2389 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
2390 conf = (s == buffer)? (uschar *)string_copy(s) : US s;
2391 }
2392
2393 /* Process all transported addresses - for LMTP or PRDR, read a status for
2394 each one. */
2395
2396 for (addr = addrlist; addr != first_addr; addr = addr->next)
2397 {
2398 if (addr->transport_return != PENDING_OK) continue;
2399
2400 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
2401 remaining addresses. Otherwise, it's a return code for just the one
2402 address. For temporary errors, add a retry item for the address so that
2403 it doesn't get tried again too soon. */
2404
2405 #ifndef DISABLE_PRDR
2406 if (lmtp || prdr_active)
2407 #else
2408 if (lmtp)
2409 #endif
2410 {
2411 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2412 ob->final_timeout))
2413 {
2414 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
2415 addr->message = string_sprintf(
2416 #ifndef DISABLE_PRDR
2417 "%s error after %s: %s", prdr_active ? "PRDR":"LMTP",
2418 #else
2419 "LMTP error after %s: %s",
2420 #endif
2421 big_buffer, string_printing(buffer));
2422 setflag(addr, af_pass_message); /* Allow message to go to user */
2423 if (buffer[0] == '5')
2424 addr->transport_return = FAIL;
2425 else
2426 {
2427 errno = ERRNO_DATA4XX;
2428 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2429 addr->transport_return = DEFER;
2430 #ifndef DISABLE_PRDR
2431 if (!prdr_active)
2432 #endif
2433 retry_add_item(addr, addr->address_retry_key, 0);
2434 }
2435 continue;
2436 }
2437 completed_address = TRUE; /* NOW we can set this flag */
2438 if ((log_extra_selector & LX_smtp_confirmation) != 0)
2439 {
2440 const uschar *s = string_printing(buffer);
2441 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
2442 conf = (s == buffer)? (uschar *)string_copy(s) : US s;
2443 }
2444 }
2445
2446 /* SMTP, or success return from LMTP for this address. Pass back the
2447 actual host that was used. */
2448
2449 addr->transport_return = OK;
2450 addr->more_errno = delivery_time;
2451 addr->host_used = host;
2452 addr->special_action = flag;
2453 addr->message = conf;
2454 #ifndef DISABLE_PRDR
2455 if (prdr_active) addr->flags |= af_prdr_used;
2456 #endif
2457 flag = '-';
2458
2459 #ifndef DISABLE_PRDR
2460 if (!prdr_active)
2461 #endif
2462 {
2463 /* Update the journal. For homonymic addresses, use the base address plus
2464 the transport name. See lots of comments in deliver.c about the reasons
2465 for the complications when homonyms are involved. Just carry on after
2466 write error, as it may prove possible to update the spool file later. */
2467
2468 if (testflag(addr, af_homonym))
2469 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2470 else
2471 sprintf(CS buffer, "%.500s\n", addr->unique);
2472
2473 DEBUG(D_deliver) debug_printf("journalling %s", buffer);
2474 len = Ustrlen(CS buffer);
2475 if (write(journal_fd, buffer, len) != len)
2476 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2477 "%s: %s", buffer, strerror(errno));
2478 }
2479 }
2480
2481 #ifndef DISABLE_PRDR
2482 if (prdr_active)
2483 {
2484 /* PRDR - get the final, overall response. For any non-success
2485 upgrade all the address statuses. */
2486 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2487 ob->final_timeout);
2488 if (!ok)
2489 {
2490 if(errno == 0 && buffer[0] == '4')
2491 {
2492 errno = ERRNO_DATA4XX;
2493 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2494 }
2495 for (addr = addrlist; addr != first_addr; addr = addr->next)
2496 if (buffer[0] == '5' || addr->transport_return == OK)
2497 addr->transport_return = PENDING_OK; /* allow set_errno action */
2498 goto RESPONSE_FAILED;
2499 }
2500
2501 /* Update the journal, or setup retry. */
2502 for (addr = addrlist; addr != first_addr; addr = addr->next)
2503 if (addr->transport_return == OK)
2504 {
2505 if (testflag(addr, af_homonym))
2506 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2507 else
2508 sprintf(CS buffer, "%.500s\n", addr->unique);
2509
2510 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s", buffer);
2511 len = Ustrlen(CS buffer);
2512 if (write(journal_fd, buffer, len) != len)
2513 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2514 "%s: %s", buffer, strerror(errno));
2515 }
2516 else if (addr->transport_return == DEFER)
2517 retry_add_item(addr, addr->address_retry_key, -2);
2518 }
2519 #endif
2520
2521 /* Ensure the journal file is pushed out to disk. */
2522
2523 if (EXIMfsync(journal_fd) < 0)
2524 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
2525 strerror(errno));
2526 }
2527 }
2528
2529
2530 /* Handle general (not specific to one address) failures here. The value of ok
2531 is used to skip over this code on the falling through case. A timeout causes a
2532 deferral. Other errors may defer or fail according to the response code, and
2533 may set up a special errno value, e.g. after connection chopped, which is
2534 assumed if errno == 0 and there is no text in the buffer. If control reaches
2535 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
2536 the problem is not related to this specific message. */
2537
2538 if (!ok)
2539 {
2540 int code;
2541
2542 RESPONSE_FAILED:
2543 save_errno = errno;
2544 message = NULL;
2545 send_quit = check_response(host, &save_errno, addrlist->more_errno,
2546 buffer, &code, &message, &pass_message);
2547 goto FAILED;
2548
2549 SEND_FAILED:
2550 save_errno = errno;
2551 code = '4';
2552 message = US string_sprintf("send() to %s [%s] failed: %s",
2553 host->name, host->address, strerror(save_errno));
2554 send_quit = FALSE;
2555 goto FAILED;
2556
2557 /* This label is jumped to directly when a TLS negotiation has failed,
2558 or was not done for a host for which it is required. Values will be set
2559 in message and save_errno, and setting_up will always be true. Treat as
2560 a temporary error. */
2561
2562 #ifdef SUPPORT_TLS
2563 TLS_FAILED:
2564 code = '4';
2565 #endif
2566
2567 /* If the failure happened while setting up the call, see if the failure was
2568 a 5xx response (this will either be on connection, or following HELO - a 5xx
2569 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
2570 never going to accept them. For other errors during setting up (timeouts or
2571 whatever), defer all addresses, and yield DEFER, so that the host is not
2572 tried again for a while. */
2573
2574 FAILED:
2575 ok = FALSE; /* For when reached by GOTO */
2576
2577 if (setting_up)
2578 {
2579 if (code == '5')
2580 set_errno(addrlist, save_errno, message, FAIL, pass_message, host);
2581 else
2582 {
2583 set_errno(addrlist, save_errno, message, DEFER, pass_message, host);
2584 yield = DEFER;
2585 }
2586 }
2587
2588 /* We want to handle timeouts after MAIL or "." and loss of connection after
2589 "." specially. They can indicate a problem with the sender address or with
2590 the contents of the message rather than a real error on the connection. These
2591 cases are treated in the same way as a 4xx response. This next bit of code
2592 does the classification. */
2593
2594 else
2595 {
2596 BOOL message_error;
2597
2598 switch(save_errno)
2599 {
2600 #ifdef EXPERIMENTAL_INTERNATIONAL
2601 case ERRNO_UTF8_FWD:
2602 code = '5';
2603 /*FALLTHROUGH*/
2604 #endif
2605 case 0:
2606 case ERRNO_MAIL4XX:
2607 case ERRNO_DATA4XX:
2608 message_error = TRUE;
2609 break;
2610
2611 case ETIMEDOUT:
2612 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
2613 Ustrncmp(smtp_command,"end ",4) == 0;
2614 break;
2615
2616 case ERRNO_SMTPCLOSED:
2617 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
2618 break;
2619
2620 default:
2621 message_error = FALSE;
2622 break;
2623 }
2624
2625 /* Handle the cases that are treated as message errors. These are:
2626
2627 (a) negative response or timeout after MAIL
2628 (b) negative response after DATA
2629 (c) negative response or timeout or dropped connection after "."
2630 (d) utf8 support required and not offered
2631
2632 It won't be a negative response or timeout after RCPT, as that is dealt
2633 with separately above. The action in all cases is to set an appropriate
2634 error code for all the addresses, but to leave yield set to OK because the
2635 host itself has not failed. Of course, it might in practice have failed
2636 when we've had a timeout, but if so, we'll discover that at the next
2637 delivery attempt. For a temporary error, set the message_defer flag, and
2638 write to the logs for information if this is not the last host. The error
2639 for the last host will be logged as part of the address's log line. */
2640
2641 if (message_error)
2642 {
2643 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
2644 set_errno(addrlist, save_errno, message, (code == '5')? FAIL : DEFER,
2645 pass_message, host);
2646
2647 /* If there's an errno, the message contains just the identity of
2648 the host. */
2649
2650 if (code != '5') /* Anything other than 5 is treated as temporary */
2651 {
2652 if (save_errno > 0)
2653 message = US string_sprintf("%s: %s", message, strerror(save_errno));
2654 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
2655 msglog_line(host, message);
2656 *message_defer = TRUE;
2657 }
2658 }
2659
2660 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
2661 ".", or some other transportation error. We defer all addresses and yield
2662 DEFER, except for the case of failed add_headers expansion, or a transport
2663 filter failure, when the yield should be ERROR, to stop it trying other
2664 hosts. */
2665
2666 else
2667 {
2668 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
2669 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
2670 set_errno(addrlist, save_errno, message, DEFER, pass_message, host);
2671 }
2672 }
2673 }
2674
2675
2676 /* If all has gone well, send_quit will be set TRUE, implying we can end the
2677 SMTP session tidily. However, if there were too many addresses to send in one
2678 message (indicated by first_addr being non-NULL) we want to carry on with the
2679 rest of them. Also, it is desirable to send more than one message down the SMTP
2680 connection if there are several waiting, provided we haven't already sent so
2681 many as to hit the configured limit. The function transport_check_waiting looks
2682 for a waiting message and returns its id. Then transport_pass_socket tries to
2683 set up a continued delivery by passing the socket on to another process. The
2684 variable send_rset is FALSE if a message has just been successfully transfered.
2685
2686 If we are already sending down a continued channel, there may be further
2687 addresses not yet delivered that are aimed at the same host, but which have not
2688 been passed in this run of the transport. In this case, continue_more will be
2689 true, and all we should do is send RSET if necessary, and return, leaving the
2690 channel open.
2691
2692 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
2693 do not want to continue with other messages down the same channel, because that
2694 can lead to looping between two or more messages, all with the same,
2695 temporarily failing address(es). [The retry information isn't updated yet, so
2696 new processes keep on trying.] We probably also don't want to try more of this
2697 message's addresses either.
2698
2699 If we have started a TLS session, we have to end it before passing the
2700 connection to a new process. However, not all servers can handle this (Exim
2701 can), so we do not pass such a connection on if the host matches
2702 hosts_nopass_tls. */
2703
2704 DEBUG(D_transport)
2705 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
2706 "yield=%d first_address is %sNULL\n", ok, send_quit, send_rset,
2707 continue_more, yield, (first_addr == NULL)? "":"not ");
2708
2709 if (completed_address && ok && send_quit)
2710 {
2711 BOOL more;
2712 smtp_compare_t t_compare;
2713
2714 t_compare.tblock = tblock;
2715 t_compare.current_sender_address = sender_address;
2716
2717 if ( first_addr != NULL
2718 || continue_more
2719 || ( ( tls_out.active < 0
2720 || verify_check_given_host(&ob->hosts_nopass_tls, host) != OK
2721 )
2722 &&
2723 transport_check_waiting(tblock->name, host->name,
2724 tblock->connection_max_messages, new_message_id, &more,
2725 (oicf)smtp_are_same_identities, (void*)&t_compare)
2726 ) )
2727 {
2728 uschar *msg;
2729 BOOL pass_message;
2730
2731 if (send_rset)
2732 {
2733 if (! (ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
2734 {
2735 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
2736 host->address, strerror(save_errno));
2737 send_quit = FALSE;
2738 }
2739 else if (! (ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2740 ob->command_timeout)))
2741 {
2742 int code;
2743 send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
2744 &pass_message);
2745 if (!send_quit)
2746 {
2747 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
2748 host->name, host->address, msg);
2749 }
2750 }
2751 }
2752
2753 /* Either RSET was not needed, or it succeeded */
2754
2755 if (ok)
2756 {
2757 if (first_addr != NULL) /* More addresses still to be sent */
2758 { /* in this run of the transport */
2759 continue_sequence++; /* Causes * in logging */
2760 goto SEND_MESSAGE;
2761 }
2762 if (continue_more) return yield; /* More addresses for another run */
2763
2764 /* Pass the socket to a new Exim process. Before doing so, we must shut
2765 down TLS. Not all MTAs allow for the continuation of the SMTP session
2766 when TLS is shut down. We test for this by sending a new EHLO. If we
2767 don't get a good response, we don't attempt to pass the socket on. */
2768
2769 #ifdef SUPPORT_TLS
2770 if (tls_out.active >= 0)
2771 {
2772 tls_close(FALSE, TRUE);
2773 if (smtps)
2774 ok = FALSE;
2775 else
2776 ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
2777 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2778 ob->command_timeout);
2779 }
2780 #endif
2781
2782 /* If the socket is successfully passed, we musn't send QUIT (or
2783 indeed anything!) from here. */
2784
2785 if (ok && transport_pass_socket(tblock->name, host->name, host->address,
2786 new_message_id, inblock.sock))
2787 {
2788 send_quit = FALSE;
2789 }
2790 }
2791
2792 /* If RSET failed and there are addresses left, they get deferred. */
2793
2794 else set_errno(first_addr, errno, msg, DEFER, FALSE, host);
2795 }
2796 }
2797
2798 /* End off tidily with QUIT unless the connection has died or the socket has
2799 been passed to another process. There has been discussion on the net about what
2800 to do after sending QUIT. The wording of the RFC suggests that it is necessary
2801 to wait for a response, but on the other hand, there isn't anything one can do
2802 with an error response, other than log it. Exim used to do that. However,
2803 further discussion suggested that it is positively advantageous not to wait for
2804 the response, but to close the session immediately. This is supposed to move
2805 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
2806 load from the server. (Hosts that are both servers and clients may not see much
2807 difference, of course.) Further discussion indicated that this was safe to do
2808 on Unix systems which have decent implementations of TCP/IP that leave the
2809 connection around for a while (TIME_WAIT) after the application has gone away.
2810 This enables the response sent by the server to be properly ACKed rather than
2811 timed out, as can happen on broken TCP/IP implementations on other OS.
2812
2813 This change is being made on 31-Jul-98. After over a year of trouble-free
2814 operation, the old commented-out code was removed on 17-Sep-99. */
2815
2816 SEND_QUIT:
2817 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2818
2819 END_OFF:
2820
2821 #ifdef SUPPORT_TLS
2822 tls_close(FALSE, TRUE);
2823 #endif
2824
2825 /* Close the socket, and return the appropriate value, first setting
2826 works because the NULL setting is passed back to the calling process, and
2827 remote_max_parallel is forced to 1 when delivering over an existing connection,
2828
2829 If all went well and continue_more is set, we shouldn't actually get here if
2830 there are further addresses, as the return above will be taken. However,
2831 writing RSET might have failed, or there may be other addresses whose hosts are
2832 specified in the transports, and therefore not visible at top level, in which
2833 case continue_more won't get set. */
2834
2835 (void)close(inblock.sock);
2836
2837 #ifdef EXPERIMENTAL_EVENT
2838 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
2839 #endif
2840
2841 continue_transport = NULL;
2842 continue_hostname = NULL;
2843 return yield;
2844 }
2845
2846
2847
2848
2849 /*************************************************
2850 * Closedown entry point *
2851 *************************************************/
2852
2853 /* This function is called when exim is passed an open smtp channel
2854 from another incarnation, but the message which it has been asked
2855 to deliver no longer exists. The channel is on stdin.
2856
2857 We might do fancy things like looking for another message to send down
2858 the channel, but if the one we sought has gone, it has probably been
2859 delivered by some other process that itself will seek further messages,
2860 so just close down our connection.
2861
2862 Argument: pointer to the transport instance block
2863 Returns: nothing
2864 */
2865
2866 void
2867 smtp_transport_closedown(transport_instance *tblock)
2868 {
2869 smtp_transport_options_block *ob =
2870 (smtp_transport_options_block *)(tblock->options_block);
2871 smtp_inblock inblock;
2872 smtp_outblock outblock;
2873 uschar buffer[256];
2874 uschar inbuffer[4096];
2875 uschar outbuffer[16];
2876
2877 inblock.sock = fileno(stdin);
2878 inblock.buffer = inbuffer;
2879 inblock.buffersize = sizeof(inbuffer);
2880 inblock.ptr = inbuffer;
2881 inblock.ptrend = inbuffer;
2882
2883 outblock.sock = inblock.sock;
2884 outblock.buffersize = sizeof(outbuffer);
2885 outblock.buffer = outbuffer;
2886 outblock.ptr = outbuffer;
2887 outblock.cmd_count = 0;
2888 outblock.authenticating = FALSE;
2889
2890 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2891 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2892 ob->command_timeout);
2893 (void)close(inblock.sock);
2894 }
2895
2896
2897
2898 /*************************************************
2899 * Prepare addresses for delivery *
2900 *************************************************/
2901
2902 /* This function is called to flush out error settings from previous delivery
2903 attempts to other hosts. It also records whether we got here via an MX record
2904 or not in the more_errno field of the address. We are interested only in
2905 addresses that are still marked DEFER - others may have got delivered to a
2906 previously considered IP address. Set their status to PENDING_DEFER to indicate
2907 which ones are relevant this time.
2908
2909 Arguments:
2910 addrlist the list of addresses
2911 host the host we are delivering to
2912
2913 Returns: the first address for this delivery
2914 */
2915
2916 static address_item *
2917 prepare_addresses(address_item *addrlist, host_item *host)
2918 {
2919 address_item *first_addr = NULL;
2920 address_item *addr;
2921 for (addr = addrlist; addr != NULL; addr = addr->next)
2922 if (addr->transport_return == DEFER)
2923 {
2924 if (first_addr == NULL) first_addr = addr;
2925 addr->transport_return = PENDING_DEFER;
2926 addr->basic_errno = 0;
2927 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
2928 addr->message = NULL;
2929 #ifdef SUPPORT_TLS
2930 addr->cipher = NULL;
2931 addr->ourcert = NULL;
2932 addr->peercert = NULL;
2933 addr->peerdn = NULL;
2934 addr->ocsp = OCSP_NOT_REQ;
2935 #endif
2936 }
2937 return first_addr;
2938 }
2939
2940
2941
2942 /*************************************************
2943 * Main entry point *
2944 *************************************************/
2945
2946 /* See local README for interface details. As this is a remote transport, it is
2947 given a chain of addresses to be delivered in one connection, if possible. It
2948 always returns TRUE, indicating that each address has its own independent
2949 status set, except if there is a setting up problem, in which case it returns
2950 FALSE. */
2951
2952 BOOL
2953 smtp_transport_entry(
2954 transport_instance *tblock, /* data for this instantiation */
2955 address_item *addrlist) /* addresses we are working on */
2956 {
2957 int cutoff_retry;
2958 int port;
2959 int hosts_defer = 0;
2960 int hosts_fail = 0;
2961 int hosts_looked_up = 0;
2962 int hosts_retry = 0;
2963 int hosts_serial = 0;
2964 int hosts_total = 0;
2965 int total_hosts_tried = 0;
2966 address_item *addr;
2967 BOOL expired = TRUE;
2968 BOOL continuing = continue_hostname != NULL;
2969 uschar *expanded_hosts = NULL;
2970 uschar *pistring;
2971 uschar *tid = string_sprintf("%s transport", tblock->name);
2972 smtp_transport_options_block *ob =
2973 (smtp_transport_options_block *)(tblock->options_block);
2974 host_item *hostlist = addrlist->host_list;
2975 host_item *host = NULL;
2976
2977 DEBUG(D_transport)
2978 {
2979 debug_printf("%s transport entered\n", tblock->name);
2980 for (addr = addrlist; addr != NULL; addr = addr->next)
2981 debug_printf(" %s\n", addr->address);
2982 if (continuing) debug_printf("already connected to %s [%s]\n",
2983 continue_hostname, continue_host_address);
2984 }
2985
2986 /* Set the flag requesting that these hosts be added to the waiting
2987 database if the delivery fails temporarily or if we are running with
2988 queue_smtp or a 2-stage queue run. This gets unset for certain
2989 kinds of error, typically those that are specific to the message. */
2990
2991 update_waiting = TRUE;
2992
2993 /* If a host list is not defined for the addresses - they must all have the
2994 same one in order to be passed to a single transport - or if the transport has
2995 a host list with hosts_override set, use the host list supplied with the
2996 transport. It is an error for this not to exist. */
2997
2998 if (hostlist == NULL || (ob->hosts_override && ob->hosts != NULL))
2999 {
3000 if (ob->hosts == NULL)
3001 {
3002 addrlist->message = string_sprintf("%s transport called with no hosts set",
3003 tblock->name);
3004 addrlist->transport_return = PANIC;
3005 return FALSE; /* Only top address has status */
3006 }
3007
3008 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
3009 ob->hosts);
3010
3011 /* If the transport's host list contains no '$' characters, and we are not
3012 randomizing, it is fixed and therefore a chain of hosts can be built once
3013 and for all, and remembered for subsequent use by other calls to this
3014 transport. If, on the other hand, the host list does contain '$', or we are
3015 randomizing its order, we have to rebuild it each time. In the fixed case,
3016 as the hosts string will never be used again, it doesn't matter that we
3017 replace all the : characters with zeros. */
3018
3019 if (ob->hostlist == NULL)
3020 {
3021 uschar *s = ob->hosts;
3022
3023 if (Ustrchr(s, '$') != NULL)
3024 {
3025 if (!(expanded_hosts = expand_string(s)))
3026 {
3027 addrlist->message = string_sprintf("failed to expand list of hosts "
3028 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
3029 addrlist->transport_return = search_find_defer? DEFER : PANIC;
3030 return FALSE; /* Only top address has status */
3031 }
3032 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
3033 "\"%s\"\n", s, expanded_hosts);
3034 s = expanded_hosts;
3035 }
3036 else
3037 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
3038
3039 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
3040
3041 /* Check that the expansion yielded something useful. */
3042 if (hostlist == NULL)
3043 {
3044 addrlist->message =
3045 string_sprintf("%s transport has empty hosts setting", tblock->name);
3046 addrlist->transport_return = PANIC;
3047 return FALSE; /* Only top address has status */
3048 }
3049
3050 /* If there was no expansion of hosts, save the host list for
3051 next time. */
3052
3053 if (!expanded_hosts) ob->hostlist = hostlist;
3054 }
3055
3056 /* This is not the first time this transport has been run in this delivery;
3057 the host list was built previously. */
3058
3059 else
3060 hostlist = ob->hostlist;
3061 }
3062
3063 /* The host list was supplied with the address. If hosts_randomize is set, we
3064 must sort it into a random order if it did not come from MX records and has not
3065 already been randomized (but don't bother if continuing down an existing
3066 connection). */
3067
3068 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continuing)
3069 {
3070 host_item *newlist = NULL;
3071 while (hostlist != NULL)
3072 {
3073 host_item *h = hostlist;
3074 hostlist = hostlist->next;
3075
3076 h->sort_key = random_number(100);
3077
3078 if (newlist == NULL)
3079 {
3080 h->next = NULL;
3081 newlist = h;
3082 }
3083 else if (h->sort_key < newlist->sort_key)
3084 {
3085 h->next = newlist;
3086 newlist = h;
3087 }
3088 else
3089 {
3090 host_item *hh = newlist;
3091 while (hh->next != NULL)
3092 {
3093 if (h->sort_key < hh->next->sort_key) break;
3094 hh = hh->next;
3095 }
3096 h->next = hh->next;
3097 hh->next = h;
3098 }
3099 }
3100
3101 hostlist = addrlist->host_list = newlist;
3102 }
3103
3104 /* Sort out the default port. */
3105
3106 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
3107
3108 /* For each host-plus-IP-address on the list:
3109
3110 . If this is a continued delivery and the host isn't the one with the
3111 current connection, skip.
3112
3113 . If the status is unusable (i.e. previously failed or retry checked), skip.
3114
3115 . If no IP address set, get the address, either by turning the name into
3116 an address, calling gethostbyname if gethostbyname is on, or by calling
3117 the DNS. The DNS may yield multiple addresses, in which case insert the
3118 extra ones into the list.
3119
3120 . Get the retry data if not previously obtained for this address and set the
3121 field which remembers the state of this address. Skip if the retry time is
3122 not reached. If not, remember whether retry data was found. The retry string
3123 contains both the name and the IP address.
3124
3125 . Scan the list of addresses and mark those whose status is DEFER as
3126 PENDING_DEFER. These are the only ones that will be processed in this cycle
3127 of the hosts loop.
3128
3129 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
3130 Some addresses may be successfully delivered, others may fail, and yet
3131 others may get temporary errors and so get marked DEFER.
3132
3133 . The return from the delivery attempt is OK if a connection was made and a
3134 valid SMTP dialogue was completed. Otherwise it is DEFER.
3135
3136 . If OK, add a "remove" retry item for this host/IPaddress, if any.
3137
3138 . If fail to connect, or other defer state, add a retry item.
3139
3140 . If there are any addresses whose status is still DEFER, carry on to the
3141 next host/IPaddress, unless we have tried the number of hosts given
3142 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
3143 there is some fancy logic for hosts_max_try that means its limit can be
3144 overstepped in some circumstances.
3145
3146 If we get to the end of the list, all hosts have deferred at least one address,
3147 or not reached their retry times. If delay_after_cutoff is unset, it requests a
3148 delivery attempt to those hosts whose last try was before the arrival time of
3149 the current message. To cope with this, we have to go round the loop a second
3150 time. After that, set the status and error data for any addresses that haven't
3151 had it set already. */
3152
3153 for (cutoff_retry = 0; expired &&
3154 cutoff_retry < ((ob->delay_after_cutoff)? 1 : 2);
3155 cutoff_retry++)
3156 {
3157 host_item *nexthost = NULL;
3158 int unexpired_hosts_tried = 0;
3159
3160 for (host = hostlist;
3161 host != NULL &&
3162 unexpired_hosts_tried < ob->hosts_max_try &&
3163 total_hosts_tried < ob->hosts_max_try_hardlimit;
3164 host = nexthost)
3165 {
3166 int rc;
3167 int host_af;
3168 uschar *rs;
3169 BOOL serialized = FALSE;
3170 BOOL host_is_expired = FALSE;
3171 BOOL message_defer = FALSE;
3172 BOOL ifchanges = FALSE;
3173 BOOL some_deferred = FALSE;
3174 address_item *first_addr = NULL;
3175 uschar *interface = NULL;
3176 uschar *retry_host_key = NULL;
3177 uschar *retry_message_key = NULL;
3178 uschar *serialize_key = NULL;
3179
3180 /* Default next host is next host. :-) But this can vary if the
3181 hosts_max_try limit is hit (see below). It may also be reset if a host
3182 address is looked up here (in case the host was multihomed). */
3183
3184 nexthost = host->next;
3185
3186 /* If the address hasn't yet been obtained from the host name, look it up
3187 now, unless the host is already marked as unusable. If it is marked as
3188 unusable, it means that the router was unable to find its IP address (in
3189 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
3190 the lookup failed last time. We don't get this far if *all* MX records
3191 point to non-existent hosts; that is treated as a hard error.
3192
3193 We can just skip this host entirely. When the hosts came from the router,
3194 the address will timeout based on the other host(s); when the address is
3195 looked up below, there is an explicit retry record added.
3196
3197 Note that we mustn't skip unusable hosts if the address is not unset; they
3198 may be needed as expired hosts on the 2nd time round the cutoff loop. */
3199
3200 if (host->address == NULL)
3201 {
3202 int new_port, flags;
3203 host_item *hh;
3204
3205 if (host->status >= hstatus_unusable)
3206 {
3207 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
3208 host->name);
3209 continue;
3210 }
3211
3212 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
3213
3214 /* The host name is permitted to have an attached port. Find it, and
3215 strip it from the name. Just remember it for now. */
3216
3217 new_port = host_item_get_port(host);
3218
3219 /* Count hosts looked up */
3220
3221 hosts_looked_up++;
3222
3223 /* Find by name if so configured, or if it's an IP address. We don't
3224 just copy the IP address, because we need the test-for-local to happen. */
3225
3226 flags = HOST_FIND_BY_A;
3227 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
3228 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
3229
3230 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
3231 rc = host_find_byname(host, NULL, flags, NULL, TRUE);
3232 else
3233 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
3234 &ob->dnssec, /* domains for request/require */
3235 NULL, NULL);
3236
3237 /* Update the host (and any additional blocks, resulting from
3238 multihoming) with a host-specific port, if any. */
3239
3240 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
3241
3242 /* Failure to find the host at this time (usually DNS temporary failure)
3243 is really a kind of routing failure rather than a transport failure.
3244 Therefore we add a retry item of the routing kind, not to stop us trying
3245 to look this name up here again, but to ensure the address gets timed
3246 out if the failures go on long enough. A complete failure at this point
3247 commonly points to a configuration error, but the best action is still
3248 to carry on for the next host. */
3249
3250 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
3251 {
3252 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
3253 expired = FALSE;
3254 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
3255 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
3256 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
3257 host->status = hstatus_unusable;
3258
3259 for (addr = addrlist; addr != NULL; addr = addr->next)
3260 {
3261 if (addr->transport_return != DEFER) continue;
3262 addr->basic_errno = ERRNO_UNKNOWNHOST;
3263 addr->message =
3264 string_sprintf("failed to lookup IP address for %s", host->name);
3265 }
3266 continue;
3267 }
3268
3269 /* If the host is actually the local host, we may have a problem, or
3270 there may be some cunning configuration going on. In the problem case,
3271 log things and give up. The default transport status is already DEFER. */
3272
3273 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
3274 {
3275 for (addr = addrlist; addr != NULL; addr = addr->next)
3276 {
3277 addr->basic_errno = 0;
3278 addr->message = string_sprintf("%s transport found host %s to be "
3279 "local", tblock->name, host->name);
3280 }
3281 goto END_TRANSPORT;
3282 }
3283 } /* End of block for IP address lookup */
3284
3285 /* If this is a continued delivery, we are interested only in the host
3286 which matches the name of the existing open channel. The check is put
3287 here after the local host lookup, in case the name gets expanded as a
3288 result of the lookup. Set expired FALSE, to save the outer loop executing
3289 twice. */
3290
3291 if (continuing && (Ustrcmp(continue_hostname, host->name) != 0 ||
3292 Ustrcmp(continue_host_address, host->address) != 0))
3293 {
3294 expired = FALSE;
3295 continue; /* With next host */
3296 }
3297
3298 /* Reset the default next host in case a multihomed host whose addresses
3299 are not looked up till just above added to the host list. */
3300
3301 nexthost = host->next;
3302
3303 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
3304 domain is in queue_smtp_domains, we don't actually want to attempt any
3305 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
3306 there is a lookup defer in queue_smtp_domains, proceed as if the domain
3307 were not in it. We don't want to hold up all SMTP deliveries! Except when
3308 doing a two-stage queue run, don't do this if forcing. */
3309
3310 if ((!deliver_force || queue_2stage) && (queue_smtp ||
3311 match_isinlist(addrlist->domain,
3312 (const uschar **)&queue_smtp_domains, 0,
3313 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
3314 {
3315 expired = FALSE;
3316 for (addr = addrlist; addr != NULL; addr = addr->next)
3317 {
3318 if (addr->transport_return != DEFER) continue;
3319 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
3320 }
3321 continue; /* With next host */
3322 }