4403fe11304ad04511e41d09ace0e4fe6b6303f2
[exim.git] / src / src / transports / smtp.c
1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
4
5 /* Copyright (c) University of Cambridge 1995 - 2016 */
6 /* See the file NOTICE for conditions of use and distribution. */
7
8 #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 #define DELIVER_BUFFER_SIZE 4096
16
17
18 /* Options specific to the smtp transport. This transport also supports LMTP
19 over TCP/IP. The options must be in alphabetic order (note that "_" comes
20 before the lower case letters). Some live in the transport_instance block so as
21 to be publicly visible; these are flagged with opt_public. */
22
23 optionlist smtp_transport_options[] = {
24 { "*expand_multi_domain", opt_stringptr | opt_hidden | opt_public,
25 (void *)offsetof(transport_instance, expand_multi_domain) },
26 { "*expand_retry_include_ip_address", opt_stringptr | opt_hidden,
27 (void *)(offsetof(smtp_transport_options_block, expand_retry_include_ip_address)) },
28
29 { "address_retry_include_sender", opt_bool,
30 (void *)offsetof(smtp_transport_options_block, address_retry_include_sender) },
31 { "allow_localhost", opt_bool,
32 (void *)offsetof(smtp_transport_options_block, allow_localhost) },
33 { "authenticated_sender", opt_stringptr,
34 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
35 { "authenticated_sender_force", opt_bool,
36 (void *)offsetof(smtp_transport_options_block, authenticated_sender_force) },
37 { "command_timeout", opt_time,
38 (void *)offsetof(smtp_transport_options_block, command_timeout) },
39 { "connect_timeout", opt_time,
40 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
41 { "connection_max_messages", opt_int | opt_public,
42 (void *)offsetof(transport_instance, connection_max_messages) },
43 { "data_timeout", opt_time,
44 (void *)offsetof(smtp_transport_options_block, data_timeout) },
45 { "delay_after_cutoff", opt_bool,
46 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
47 #ifndef DISABLE_DKIM
48 { "dkim_canon", opt_stringptr,
49 (void *)offsetof(smtp_transport_options_block, dkim.dkim_canon) },
50 { "dkim_domain", opt_stringptr,
51 (void *)offsetof(smtp_transport_options_block, dkim.dkim_domain) },
52 { "dkim_private_key", opt_stringptr,
53 (void *)offsetof(smtp_transport_options_block, dkim.dkim_private_key) },
54 { "dkim_selector", opt_stringptr,
55 (void *)offsetof(smtp_transport_options_block, dkim.dkim_selector) },
56 { "dkim_sign_headers", opt_stringptr,
57 (void *)offsetof(smtp_transport_options_block, dkim.dkim_sign_headers) },
58 { "dkim_strict", opt_stringptr,
59 (void *)offsetof(smtp_transport_options_block, dkim.dkim_strict) },
60 #endif
61 { "dns_qualify_single", opt_bool,
62 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
63 { "dns_search_parents", opt_bool,
64 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
65 { "dnssec_request_domains", opt_stringptr,
66 (void *)offsetof(smtp_transport_options_block, dnssec.request) },
67 { "dnssec_require_domains", opt_stringptr,
68 (void *)offsetof(smtp_transport_options_block, dnssec.require) },
69 { "dscp", opt_stringptr,
70 (void *)offsetof(smtp_transport_options_block, dscp) },
71 { "fallback_hosts", opt_stringptr,
72 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
73 { "final_timeout", opt_time,
74 (void *)offsetof(smtp_transport_options_block, final_timeout) },
75 { "gethostbyname", opt_bool,
76 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
77 { "helo_data", opt_stringptr,
78 (void *)offsetof(smtp_transport_options_block, helo_data) },
79 { "hosts", opt_stringptr,
80 (void *)offsetof(smtp_transport_options_block, hosts) },
81 { "hosts_avoid_esmtp", opt_stringptr,
82 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
83 { "hosts_avoid_pipelining", opt_stringptr,
84 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
85 #ifdef SUPPORT_TLS
86 { "hosts_avoid_tls", opt_stringptr,
87 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
88 #endif
89 { "hosts_max_try", opt_int,
90 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
91 { "hosts_max_try_hardlimit", opt_int,
92 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
93 #ifdef SUPPORT_TLS
94 { "hosts_nopass_tls", opt_stringptr,
95 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
96 #endif
97 { "hosts_override", opt_bool,
98 (void *)offsetof(smtp_transport_options_block, hosts_override) },
99 { "hosts_randomize", opt_bool,
100 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
101 #if defined(SUPPORT_TLS) && !defined(DISABLE_OCSP)
102 { "hosts_request_ocsp", opt_stringptr,
103 (void *)offsetof(smtp_transport_options_block, hosts_request_ocsp) },
104 #endif
105 { "hosts_require_auth", opt_stringptr,
106 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
107 #ifdef SUPPORT_TLS
108 # ifdef EXPERIMENTAL_DANE
109 { "hosts_require_dane", opt_stringptr,
110 (void *)offsetof(smtp_transport_options_block, hosts_require_dane) },
111 # endif
112 # ifndef DISABLE_OCSP
113 { "hosts_require_ocsp", opt_stringptr,
114 (void *)offsetof(smtp_transport_options_block, hosts_require_ocsp) },
115 # endif
116 { "hosts_require_tls", opt_stringptr,
117 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
118 #endif
119 { "hosts_try_auth", opt_stringptr,
120 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
121 { "hosts_try_chunking", opt_stringptr,
122 (void *)offsetof(smtp_transport_options_block, hosts_try_chunking) },
123 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
124 { "hosts_try_dane", opt_stringptr,
125 (void *)offsetof(smtp_transport_options_block, hosts_try_dane) },
126 #endif
127 #ifndef DISABLE_PRDR
128 { "hosts_try_prdr", opt_stringptr,
129 (void *)offsetof(smtp_transport_options_block, hosts_try_prdr) },
130 #endif
131 #ifdef SUPPORT_TLS
132 { "hosts_verify_avoid_tls", opt_stringptr,
133 (void *)offsetof(smtp_transport_options_block, hosts_verify_avoid_tls) },
134 #endif
135 { "interface", opt_stringptr,
136 (void *)offsetof(smtp_transport_options_block, interface) },
137 { "keepalive", opt_bool,
138 (void *)offsetof(smtp_transport_options_block, keepalive) },
139 { "lmtp_ignore_quota", opt_bool,
140 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
141 { "max_rcpt", opt_int | opt_public,
142 (void *)offsetof(transport_instance, max_addresses) },
143 { "multi_domain", opt_expand_bool | opt_public,
144 (void *)offsetof(transport_instance, multi_domain) },
145 { "port", opt_stringptr,
146 (void *)offsetof(smtp_transport_options_block, port) },
147 { "protocol", opt_stringptr,
148 (void *)offsetof(smtp_transport_options_block, protocol) },
149 { "retry_include_ip_address", opt_expand_bool,
150 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
151 { "serialize_hosts", opt_stringptr,
152 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
153 { "size_addition", opt_int,
154 (void *)offsetof(smtp_transport_options_block, size_addition) }
155 #ifdef SUPPORT_SOCKS
156 ,{ "socks_proxy", opt_stringptr,
157 (void *)offsetof(smtp_transport_options_block, socks_proxy) }
158 #endif
159 #ifdef SUPPORT_TLS
160 ,{ "tls_certificate", opt_stringptr,
161 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
162 { "tls_crl", opt_stringptr,
163 (void *)offsetof(smtp_transport_options_block, tls_crl) },
164 { "tls_dh_min_bits", opt_int,
165 (void *)offsetof(smtp_transport_options_block, tls_dh_min_bits) },
166 { "tls_privatekey", opt_stringptr,
167 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
168 { "tls_require_ciphers", opt_stringptr,
169 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
170 { "tls_sni", opt_stringptr,
171 (void *)offsetof(smtp_transport_options_block, tls_sni) },
172 { "tls_tempfail_tryclear", opt_bool,
173 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
174 { "tls_try_verify_hosts", opt_stringptr,
175 (void *)offsetof(smtp_transport_options_block, tls_try_verify_hosts) },
176 { "tls_verify_cert_hostnames", opt_stringptr,
177 (void *)offsetof(smtp_transport_options_block,tls_verify_cert_hostnames)},
178 { "tls_verify_certificates", opt_stringptr,
179 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) },
180 { "tls_verify_hosts", opt_stringptr,
181 (void *)offsetof(smtp_transport_options_block, tls_verify_hosts) }
182 #endif
183 };
184
185 /* Size of the options list. An extern variable has to be used so that its
186 address can appear in the tables drtables.c. */
187
188 int smtp_transport_options_count =
189 sizeof(smtp_transport_options)/sizeof(optionlist);
190
191 /* Default private options block for the smtp transport. */
192
193 smtp_transport_options_block smtp_transport_option_defaults = {
194 NULL, /* hosts */
195 NULL, /* fallback_hosts */
196 NULL, /* hostlist */
197 NULL, /* fallback_hostlist */
198 NULL, /* authenticated_sender */
199 US"$primary_hostname", /* helo_data */
200 NULL, /* interface */
201 NULL, /* port */
202 US"smtp", /* protocol */
203 NULL, /* DSCP */
204 NULL, /* serialize_hosts */
205 NULL, /* hosts_try_auth */
206 NULL, /* hosts_require_auth */
207 US"*", /* hosts_try_chunking */
208 #ifdef EXPERIMENTAL_DANE
209 NULL, /* hosts_try_dane */
210 NULL, /* hosts_require_dane */
211 #endif
212 #ifndef DISABLE_PRDR
213 US"*", /* hosts_try_prdr */
214 #endif
215 #ifndef DISABLE_OCSP
216 US"*", /* hosts_request_ocsp (except under DANE; tls_client_start()) */
217 NULL, /* hosts_require_ocsp */
218 #endif
219 NULL, /* hosts_require_tls */
220 NULL, /* hosts_avoid_tls */
221 NULL, /* hosts_verify_avoid_tls */
222 NULL, /* hosts_avoid_pipelining */
223 NULL, /* hosts_avoid_esmtp */
224 NULL, /* hosts_nopass_tls */
225 5*60, /* command_timeout */
226 5*60, /* connect_timeout; shorter system default overrides */
227 5*60, /* data timeout */
228 10*60, /* final timeout */
229 1024, /* size_addition */
230 5, /* hosts_max_try */
231 50, /* hosts_max_try_hardlimit */
232 TRUE, /* address_retry_include_sender */
233 FALSE, /* allow_localhost */
234 FALSE, /* authenticated_sender_force */
235 FALSE, /* gethostbyname */
236 TRUE, /* dns_qualify_single */
237 FALSE, /* dns_search_parents */
238 { NULL, NULL }, /* dnssec_domains {request,require} */
239 TRUE, /* delay_after_cutoff */
240 FALSE, /* hosts_override */
241 FALSE, /* hosts_randomize */
242 TRUE, /* keepalive */
243 FALSE, /* lmtp_ignore_quota */
244 NULL, /* expand_retry_include_ip_address */
245 TRUE /* retry_include_ip_address */
246 #ifdef SUPPORT_SOCKS
247 ,NULL /* socks_proxy */
248 #endif
249 #ifdef SUPPORT_TLS
250 ,NULL, /* tls_certificate */
251 NULL, /* tls_crl */
252 NULL, /* tls_privatekey */
253 NULL, /* tls_require_ciphers */
254 NULL, /* tls_sni */
255 US"system", /* tls_verify_certificates */
256 EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
257 /* tls_dh_min_bits */
258 TRUE, /* tls_tempfail_tryclear */
259 NULL, /* tls_verify_hosts */
260 US"*", /* tls_try_verify_hosts */
261 US"*" /* tls_verify_cert_hostnames */
262 #endif
263 #ifndef DISABLE_DKIM
264 , {NULL, /* dkim_canon */
265 NULL, /* dkim_domain */
266 NULL, /* dkim_private_key */
267 NULL, /* dkim_selector */
268 NULL, /* dkim_sign_headers */
269 NULL, /* dkim_strict */
270 FALSE} /* dot_stuffed */
271 #endif
272 };
273
274 /* some DSN flags for use later */
275
276 static int rf_list[] = {rf_notify_never, rf_notify_success,
277 rf_notify_failure, rf_notify_delay };
278
279 static uschar *rf_names[] = { US"NEVER", US"SUCCESS", US"FAILURE", US"DELAY" };
280
281
282
283 /* Local statics */
284
285 static uschar *smtp_command; /* Points to last cmd for error messages */
286 static uschar *mail_command; /* Points to MAIL cmd for error messages */
287 static BOOL update_waiting; /* TRUE to update the "wait" database */
288 static BOOL pipelining_active; /* current transaction is in pipe mode */
289
290
291 /*************************************************
292 * Setup entry point *
293 *************************************************/
294
295 /* This function is called when the transport is about to be used,
296 but before running it in a sub-process. It is used for two things:
297
298 (1) To set the fallback host list in addresses, when delivering.
299 (2) To pass back the interface, port, protocol, and other options, for use
300 during callout verification.
301
302 Arguments:
303 tblock pointer to the transport instance block
304 addrlist list of addresses about to be transported
305 tf if not NULL, pointer to block in which to return options
306 uid the uid that will be set (not used)
307 gid the gid that will be set (not used)
308 errmsg place for error message (not used)
309
310 Returns: OK always (FAIL, DEFER not used)
311 */
312
313 static int
314 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
315 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
316 {
317 smtp_transport_options_block *ob =
318 (smtp_transport_options_block *)(tblock->options_block);
319
320 errmsg = errmsg; /* Keep picky compilers happy */
321 uid = uid;
322 gid = gid;
323
324 /* Pass back options if required. This interface is getting very messy. */
325
326 if (tf != NULL)
327 {
328 tf->interface = ob->interface;
329 tf->port = ob->port;
330 tf->protocol = ob->protocol;
331 tf->hosts = ob->hosts;
332 tf->hosts_override = ob->hosts_override;
333 tf->hosts_randomize = ob->hosts_randomize;
334 tf->gethostbyname = ob->gethostbyname;
335 tf->qualify_single = ob->dns_qualify_single;
336 tf->search_parents = ob->dns_search_parents;
337 tf->helo_data = ob->helo_data;
338 }
339
340 /* Set the fallback host list for all the addresses that don't have fallback
341 host lists, provided that the local host wasn't present in the original host
342 list. */
343
344 if (!testflag(addrlist, af_local_host_removed))
345 {
346 for (; addrlist != NULL; addrlist = addrlist->next)
347 if (addrlist->fallback_hosts == NULL)
348 addrlist->fallback_hosts = ob->fallback_hostlist;
349 }
350
351 return OK;
352 }
353
354
355
356 /*************************************************
357 * Initialization entry point *
358 *************************************************/
359
360 /* Called for each instance, after its options have been read, to
361 enable consistency checks to be done, or anything else that needs
362 to be set up.
363
364 Argument: pointer to the transport instance block
365 Returns: nothing
366 */
367
368 void
369 smtp_transport_init(transport_instance *tblock)
370 {
371 smtp_transport_options_block *ob =
372 (smtp_transport_options_block *)(tblock->options_block);
373
374 /* Retry_use_local_part defaults FALSE if unset */
375
376 if (tblock->retry_use_local_part == TRUE_UNSET)
377 tblock->retry_use_local_part = FALSE;
378
379 /* Set the default port according to the protocol */
380
381 if (ob->port == NULL)
382 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
383 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
384
385 /* Set up the setup entry point, to be called before subprocesses for this
386 transport. */
387
388 tblock->setup = smtp_transport_setup;
389
390 /* Complain if any of the timeouts are zero. */
391
392 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
393 ob->final_timeout <= 0)
394 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
395 "command, data, or final timeout value is zero for %s transport",
396 tblock->name);
397
398 /* If hosts_override is set and there are local hosts, set the global
399 flag that stops verify from showing router hosts. */
400
401 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
402
403 /* If there are any fallback hosts listed, build a chain of host items
404 for them, but do not do any lookups at this time. */
405
406 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
407 }
408
409
410
411
412
413 /*************************************************
414 * Set delivery info into all active addresses *
415 *************************************************/
416
417 /* Only addresses whose status is >= PENDING are relevant. A lesser
418 status means that an address is not currently being processed.
419
420 Arguments:
421 addrlist points to a chain of addresses
422 errno_value to put in each address's errno field
423 msg to put in each address's message field
424 rc to put in each address's transport_return field
425 pass_message if TRUE, set the "pass message" flag in the address
426 host if set, mark addrs as having used this host
427 smtp_greeting from peer
428 helo_response from peer
429
430 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
431 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
432 this particular type of timeout.
433
434 Returns: nothing
435 */
436
437 static void
438 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
439 BOOL pass_message, host_item * host
440 #ifdef EXPERIMENTAL_DSN_INFO
441 , const uschar * smtp_greeting, const uschar * helo_response
442 #endif
443 )
444 {
445 address_item *addr;
446 int orvalue = 0;
447 if (errno_value == ERRNO_CONNECTTIMEOUT)
448 {
449 errno_value = ETIMEDOUT;
450 orvalue = RTEF_CTOUT;
451 }
452 for (addr = addrlist; addr; addr = addr->next)
453 if (addr->transport_return >= PENDING)
454 {
455 addr->basic_errno = errno_value;
456 addr->more_errno |= orvalue;
457 if (msg != NULL)
458 {
459 addr->message = msg;
460 if (pass_message) setflag(addr, af_pass_message);
461 }
462 addr->transport_return = rc;
463 if (host)
464 {
465 addr->host_used = host;
466 #ifdef EXPERIMENTAL_DSN_INFO
467 if (smtp_greeting)
468 {uschar * s = Ustrchr(smtp_greeting, '\n'); if (s) *s = '\0';}
469 addr->smtp_greeting = smtp_greeting;
470
471 if (helo_response)
472 {uschar * s = Ustrchr(helo_response, '\n'); if (s) *s = '\0';}
473 addr->helo_response = helo_response;
474 #endif
475 }
476 }
477 }
478
479 static void
480 set_errno_nohost(address_item *addrlist, int errno_value, uschar *msg, int rc,
481 BOOL pass_message)
482 {
483 set_errno(addrlist, errno_value, msg, rc, pass_message, NULL
484 #ifdef EXPERIMENTAL_DSN_INFO
485 , NULL, NULL
486 #endif
487 );
488 }
489
490
491 /*************************************************
492 * Check an SMTP response *
493 *************************************************/
494
495 /* This function is given an errno code and the SMTP response buffer
496 to analyse, together with the host identification for generating messages. It
497 sets an appropriate message and puts the first digit of the response code into
498 the yield variable. If no response was actually read, a suitable digit is
499 chosen.
500
501 Arguments:
502 host the current host, to get its name for messages
503 errno_value pointer to the errno value
504 more_errno from the top address for use with ERRNO_FILTER_FAIL
505 buffer the SMTP response buffer
506 yield where to put a one-digit SMTP response code
507 message where to put an errror message
508 pass_message set TRUE if message is an SMTP response
509
510 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
511 */
512
513 static BOOL
514 check_response(host_item *host, int *errno_value, int more_errno,
515 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
516 {
517 uschar * pl = pipelining_active ? US"pipelined " : US"";
518
519 *yield = '4'; /* Default setting is to give a temporary error */
520
521 /* Handle response timeout */
522
523 if (*errno_value == ETIMEDOUT)
524 {
525 *message = US string_sprintf("SMTP timeout after %s%s",
526 pl, smtp_command);
527 if (transport_count > 0)
528 *message = US string_sprintf("%s (%d bytes written)", *message,
529 transport_count);
530 return FALSE;
531 }
532
533 /* Handle malformed SMTP response */
534
535 if (*errno_value == ERRNO_SMTPFORMAT)
536 {
537 const uschar *malfresp = string_printing(buffer);
538 while (isspace(*malfresp)) malfresp++;
539 *message = *malfresp == 0
540 ? string_sprintf("Malformed SMTP reply (an empty line) "
541 "in response to %s%s", pl, smtp_command)
542 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
543 pl, smtp_command, malfresp);
544 return FALSE;
545 }
546
547 /* Handle a failed filter process error; can't send QUIT as we mustn't
548 end the DATA. */
549
550 if (*errno_value == ERRNO_FILTER_FAIL)
551 {
552 *message = US string_sprintf("transport filter process failed (%d)%s",
553 more_errno,
554 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
555 return FALSE;
556 }
557
558 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
559 end the DATA. */
560
561 if (*errno_value == ERRNO_CHHEADER_FAIL)
562 {
563 *message =
564 US string_sprintf("failed to expand headers_add or headers_remove: %s",
565 expand_string_message);
566 return FALSE;
567 }
568
569 /* Handle failure to write a complete data block */
570
571 if (*errno_value == ERRNO_WRITEINCOMPLETE)
572 {
573 *message = US string_sprintf("failed to write a data block");
574 return FALSE;
575 }
576
577 #ifdef SUPPORT_I18N
578 /* Handle lack of advertised SMTPUTF8, for international message */
579 if (*errno_value == ERRNO_UTF8_FWD)
580 {
581 *message = US string_sprintf("utf8 support required but not offered for forwarding");
582 DEBUG(D_deliver|D_transport) debug_printf("%s\n", *message);
583 return TRUE;
584 }
585 #endif
586
587 /* Handle error responses from the remote mailer. */
588
589 if (buffer[0] != 0)
590 {
591 const uschar *s = string_printing(buffer);
592 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
593 "%s", pl, smtp_command, s);
594 *pass_message = TRUE;
595 *yield = buffer[0];
596 return TRUE;
597 }
598
599 /* No data was read. If there is no errno, this must be the EOF (i.e.
600 connection closed) case, which causes deferral. An explicit connection reset
601 error has the same effect. Otherwise, put the host's identity in the message,
602 leaving the errno value to be interpreted as well. In all cases, we have to
603 assume the connection is now dead. */
604
605 if (*errno_value == 0 || *errno_value == ECONNRESET)
606 {
607 *errno_value = ERRNO_SMTPCLOSED;
608 *message = US string_sprintf("Remote host closed connection "
609 "in response to %s%s", pl, smtp_command);
610 }
611 else *message = US string_sprintf("%s [%s]", host->name, host->address);
612
613 return FALSE;
614 }
615
616
617
618 /*************************************************
619 * Write error message to logs *
620 *************************************************/
621
622 /* This writes to the main log and to the message log.
623
624 Arguments:
625 addr the address item containing error information
626 host the current host
627
628 Returns: nothing
629 */
630
631 static void
632 write_logs(address_item *addr, host_item *host)
633 {
634 uschar * message = string_sprintf("H=%s [%s]", host->name, host->address);
635
636 if (LOGGING(outgoing_port))
637 message = string_sprintf("%s:%d", message,
638 host->port == PORT_NONE ? 25 : host->port);
639 if (addr->message)
640 {
641 message = string_sprintf("%s: %s", message, addr->message);
642 if (addr->basic_errno > 0)
643 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
644 log_write(0, LOG_MAIN, "%s", message);
645 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
646 }
647 else
648 {
649 const uschar * s = exim_errstr(addr->basic_errno);
650 log_write(0, LOG_MAIN, "%s %s", message, s);
651 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), message, s);
652 }
653 }
654
655 static void
656 msglog_line(host_item * host, uschar * message)
657 {
658 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
659 host->name, host->address, message);
660 }
661
662
663
664 #ifndef DISABLE_EVENT
665 /*************************************************
666 * Post-defer action *
667 *************************************************/
668
669 /* This expands an arbitrary per-transport string.
670 It might, for example, be used to write to the database log.
671
672 Arguments:
673 addr the address item containing error information
674 host the current host
675
676 Returns: nothing
677 */
678
679 static void
680 deferred_event_raise(address_item *addr, host_item *host)
681 {
682 uschar * action = addr->transport->event_action;
683 const uschar * save_domain;
684 uschar * save_local;
685
686 if (!action)
687 return;
688
689 save_domain = deliver_domain;
690 save_local = deliver_localpart;
691
692 /*XXX would ip & port already be set up? */
693 deliver_host_address = string_copy(host->address);
694 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
695 event_defer_errno = addr->basic_errno;
696
697 router_name = addr->router->name;
698 transport_name = addr->transport->name;
699 deliver_domain = addr->domain;
700 deliver_localpart = addr->local_part;
701
702 (void) event_raise(action, US"msg:host:defer",
703 addr->message
704 ? addr->basic_errno > 0
705 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
706 : string_copy(addr->message)
707 : addr->basic_errno > 0
708 ? string_copy(US strerror(addr->basic_errno))
709 : NULL);
710
711 deliver_localpart = save_local;
712 deliver_domain = save_domain;
713 router_name = transport_name = NULL;
714 }
715 #endif
716
717 /*************************************************
718 * Synchronize SMTP responses *
719 *************************************************/
720
721 /* This function is called from smtp_deliver() to receive SMTP responses from
722 the server, and match them up with the commands to which they relate. When
723 PIPELINING is not in use, this function is called after every command, and is
724 therefore somewhat over-engineered, but it is simpler to use a single scheme
725 that works both with and without PIPELINING instead of having two separate sets
726 of code.
727
728 The set of commands that are buffered up with pipelining may start with MAIL
729 and may end with DATA; in between are RCPT commands that correspond to the
730 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
731 etc.) are never buffered.
732
733 Errors after MAIL or DATA abort the whole process leaving the response in the
734 buffer. After MAIL, pending responses are flushed, and the original command is
735 re-instated in big_buffer for error messages. For RCPT commands, the remote is
736 permitted to reject some recipient addresses while accepting others. However
737 certain errors clearly abort the whole process. Set the value in
738 transport_return to PENDING_OK if the address is accepted. If there is a
739 subsequent general error, it will get reset accordingly. If not, it will get
740 converted to OK at the end.
741
742 Arguments:
743 addrlist the complete address list
744 include_affixes TRUE if affixes include in RCPT
745 sync_addr ptr to the ptr of the one to start scanning at (updated)
746 host the host we are connected to
747 count the number of responses to read
748 address_retry_
749 include_sender true if 4xx retry is to include the sender it its key
750 pending_MAIL true if the first response is for MAIL
751 pending_DATA 0 if last command sent was not DATA
752 +1 if previously had a good recipient
753 -1 if not previously had a good recipient
754 inblock incoming SMTP block
755 timeout timeout value
756 buffer buffer for reading response
757 buffsize size of buffer
758
759 Returns: 3 if at least one address had 2xx and one had 5xx
760 2 if at least one address had 5xx but none had 2xx
761 1 if at least one host had a 2xx response, but none had 5xx
762 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
763 -1 timeout while reading RCPT response
764 -2 I/O or other non-response error for RCPT
765 -3 DATA or MAIL failed - errno and buffer set
766 */
767
768 static int
769 sync_responses(address_item *addrlist, BOOL include_affixes,
770 address_item **sync_addr, host_item *host, int count,
771 BOOL address_retry_include_sender, BOOL pending_MAIL,
772 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
773 int buffsize)
774 {
775 address_item *addr = *sync_addr;
776 int yield = 0;
777
778 /* Handle the response for a MAIL command. On error, reinstate the original
779 command in big_buffer for error message use, and flush any further pending
780 responses before returning, except after I/O errors and timeouts. */
781
782 if (pending_MAIL)
783 {
784 count--;
785 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
786 {
787 DEBUG(D_transport) debug_printf("bad response for MAIL\n");
788 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
789 if (errno == 0 && buffer[0] != 0)
790 {
791 uschar flushbuffer[4096];
792 int save_errno = 0;
793 if (buffer[0] == '4')
794 {
795 save_errno = ERRNO_MAIL4XX;
796 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
797 }
798 while (count-- > 0)
799 {
800 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
801 '2', timeout)
802 && (errno != 0 || flushbuffer[0] == 0))
803 break;
804 }
805 errno = save_errno;
806 }
807
808 if (pending_DATA) count--; /* Number of RCPT responses to come */
809 while (count-- > 0) /* Mark any pending addrs with the host used */
810 {
811 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
812 addr->host_used = host;
813 addr = addr->next;
814 }
815 return -3;
816 }
817 }
818
819 if (pending_DATA) count--; /* Number of RCPT responses to come */
820
821 /* Read and handle the required number of RCPT responses, matching each one up
822 with an address by scanning for the next address whose status is PENDING_DEFER.
823 */
824
825 while (count-- > 0)
826 {
827 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
828
829 /* The address was accepted */
830 addr->host_used = host;
831
832 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
833 {
834 yield |= 1;
835 addr->transport_return = PENDING_OK;
836
837 /* If af_dr_retry_exists is set, there was a routing delay on this address;
838 ensure that any address-specific retry record is expunged. We do this both
839 for the basic key and for the version that also includes the sender. */
840
841 if (testflag(addr, af_dr_retry_exists))
842 {
843 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
844 sender_address);
845 retry_add_item(addr, altkey, rf_delete);
846 retry_add_item(addr, addr->address_retry_key, rf_delete);
847 }
848 }
849
850 /* Timeout while reading the response */
851
852 else if (errno == ETIMEDOUT)
853 {
854 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
855 transport_rcpt_address(addr, include_affixes));
856 set_errno_nohost(addrlist, ETIMEDOUT, message, DEFER, FALSE);
857 retry_add_item(addr, addr->address_retry_key, 0);
858 update_waiting = FALSE;
859 return -1;
860 }
861
862 /* Handle other errors in obtaining an SMTP response by returning -1. This
863 will cause all the addresses to be deferred. Restore the SMTP command in
864 big_buffer for which we are checking the response, so the error message
865 makes sense. */
866
867 else if (errno != 0 || buffer[0] == 0)
868 {
869 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
870 transport_rcpt_address(addr, include_affixes));
871 return -2;
872 }
873
874 /* Handle SMTP permanent and temporary response codes. */
875
876 else
877 {
878 addr->message =
879 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
880 "%s", transport_rcpt_address(addr, include_affixes),
881 string_printing(buffer));
882 setflag(addr, af_pass_message);
883 msglog_line(host, addr->message);
884
885 /* The response was 5xx */
886
887 if (buffer[0] == '5')
888 {
889 addr->transport_return = FAIL;
890 yield |= 2;
891 }
892
893 /* The response was 4xx */
894
895 else
896 {
897 addr->transport_return = DEFER;
898 addr->basic_errno = ERRNO_RCPT4XX;
899 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
900
901 #ifndef DISABLE_EVENT
902 event_defer_errno = addr->more_errno;
903 msg_event_raise(US"msg:rcpt:host:defer", addr);
904 #endif
905
906 /* Log temporary errors if there are more hosts to be tried.
907 If not, log this last one in the == line. */
908
909 if (host->next)
910 log_write(0, LOG_MAIN, "H=%s [%s]: %s", host->name, host->address, addr->message);
911
912 #ifndef DISABLE_EVENT
913 else
914 msg_event_raise(US"msg:rcpt:defer", addr);
915 #endif
916
917 /* Do not put this message on the list of those waiting for specific
918 hosts, as otherwise it is likely to be tried too often. */
919
920 update_waiting = FALSE;
921
922 /* Add a retry item for the address so that it doesn't get tried again
923 too soon. If address_retry_include_sender is true, add the sender address
924 to the retry key. */
925
926 if (address_retry_include_sender)
927 {
928 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
929 sender_address);
930 retry_add_item(addr, altkey, 0);
931 }
932 else retry_add_item(addr, addr->address_retry_key, 0);
933 }
934 }
935 } /* Loop for next RCPT response */
936
937 /* Update where to start at for the next block of responses, unless we
938 have already handled all the addresses. */
939
940 if (addr != NULL) *sync_addr = addr->next;
941
942 /* Handle a response to DATA. If we have not had any good recipients, either
943 previously or in this block, the response is ignored. */
944
945 if (pending_DATA != 0 &&
946 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
947 {
948 int code;
949 uschar *msg;
950 BOOL pass_message;
951 if (pending_DATA > 0 || (yield & 1) != 0)
952 {
953 if (errno == 0 && buffer[0] == '4')
954 {
955 errno = ERRNO_DATA4XX;
956 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
957 }
958 return -3;
959 }
960 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
961 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
962 "is in use and there were no good recipients\n", msg);
963 }
964
965 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
966 present) received 3xx. If any RCPTs were handled and yielded anything other
967 than 4xx, yield will be set non-zero. */
968
969 return yield;
970 }
971
972
973
974 /* Do the client side of smtp-level authentication */
975 /*
976 Arguments:
977 buffer EHLO response from server (gets overwritten)
978 addrlist chain of potential addresses to deliver
979 host host to deliver to
980 ob transport options
981 ibp, obp comms channel control blocks
982
983 Returns:
984 OK Success, or failed (but not required): global "smtp_authenticated" set
985 DEFER Failed authentication (and was required)
986 ERROR Internal problem
987
988 FAIL_SEND Failed communications - transmit
989 FAIL - response
990 */
991
992 int
993 smtp_auth(uschar *buffer, unsigned bufsize, address_item *addrlist, host_item *host,
994 smtp_transport_options_block *ob, BOOL is_esmtp,
995 smtp_inblock *ibp, smtp_outblock *obp)
996 {
997 int require_auth;
998 uschar *fail_reason = US"server did not advertise AUTH support";
999
1000 smtp_authenticated = FALSE;
1001 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
1002 require_auth = verify_check_given_host(&ob->hosts_require_auth, host);
1003
1004 if (is_esmtp && !regex_AUTH) regex_AUTH =
1005 regex_must_compile(US"\\n250[\\s\\-]AUTH\\s+([\\-\\w\\s]+)(?:\\n|$)",
1006 FALSE, TRUE);
1007
1008 if (is_esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
1009 {
1010 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
1011 expand_nmax = -1; /* reset */
1012
1013 /* Must not do this check until after we have saved the result of the
1014 regex match above. */
1015
1016 if (require_auth == OK ||
1017 verify_check_given_host(&ob->hosts_try_auth, host) == OK)
1018 {
1019 auth_instance *au;
1020 fail_reason = US"no common mechanisms were found";
1021
1022 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1023
1024 /* Scan the configured authenticators looking for one which is configured
1025 for use as a client, which is not suppressed by client_condition, and
1026 whose name matches an authentication mechanism supported by the server.
1027 If one is found, attempt to authenticate by calling its client function.
1028 */
1029
1030 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1031 {
1032 uschar *p = names;
1033 if (!au->client ||
1034 (au->client_condition != NULL &&
1035 !expand_check_condition(au->client_condition, au->name,
1036 US"client authenticator")))
1037 {
1038 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1039 au->name,
1040 (au->client)? "client_condition is false" :
1041 "not configured as a client");
1042 continue;
1043 }
1044
1045 /* Loop to scan supported server mechanisms */
1046
1047 while (*p != 0)
1048 {
1049 int rc;
1050 int len = Ustrlen(au->public_name);
1051 while (isspace(*p)) p++;
1052
1053 if (strncmpic(au->public_name, p, len) != 0 ||
1054 (p[len] != 0 && !isspace(p[len])))
1055 {
1056 while (*p != 0 && !isspace(*p)) p++;
1057 continue;
1058 }
1059
1060 /* Found data for a listed mechanism. Call its client entry. Set
1061 a flag in the outblock so that data is overwritten after sending so
1062 that reflections don't show it. */
1063
1064 fail_reason = US"authentication attempt(s) failed";
1065 obp->authenticating = TRUE;
1066 rc = (au->info->clientcode)(au, ibp, obp,
1067 ob->command_timeout, buffer, bufsize);
1068 obp->authenticating = FALSE;
1069 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1070 au->name, rc);
1071
1072 /* A temporary authentication failure must hold up delivery to
1073 this host. After a permanent authentication failure, we carry on
1074 to try other authentication methods. If all fail hard, try to
1075 deliver the message unauthenticated unless require_auth was set. */
1076
1077 switch(rc)
1078 {
1079 case OK:
1080 smtp_authenticated = TRUE; /* stops the outer loop */
1081 client_authenticator = au->name;
1082 if (au->set_client_id != NULL)
1083 client_authenticated_id = expand_string(au->set_client_id);
1084 break;
1085
1086 /* Failure after writing a command */
1087
1088 case FAIL_SEND:
1089 return FAIL_SEND;
1090
1091 /* Failure after reading a response */
1092
1093 case FAIL:
1094 if (errno != 0 || buffer[0] != '5') return FAIL;
1095 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1096 au->name, host->name, host->address, buffer);
1097 break;
1098
1099 /* Failure by some other means. In effect, the authenticator
1100 decided it wasn't prepared to handle this case. Typically this
1101 is the result of "fail" in an expansion string. Do we need to
1102 log anything here? Feb 2006: a message is now put in the buffer
1103 if logging is required. */
1104
1105 case CANCELLED:
1106 if (*buffer != 0)
1107 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1108 "authentication H=%s [%s] %s", au->name, host->name,
1109 host->address, buffer);
1110 break;
1111
1112 /* Internal problem, message in buffer. */
1113
1114 case ERROR:
1115 set_errno_nohost(addrlist, ERRNO_AUTHPROB, string_copy(buffer),
1116 DEFER, FALSE);
1117 return ERROR;
1118 }
1119
1120 break; /* If not authenticated, try next authenticator */
1121 } /* Loop for scanning supported server mechanisms */
1122 } /* Loop for further authenticators */
1123 }
1124 }
1125
1126 /* If we haven't authenticated, but are required to, give up. */
1127
1128 if (require_auth == OK && !smtp_authenticated)
1129 {
1130 set_errno_nohost(addrlist, ERRNO_AUTHFAIL,
1131 string_sprintf("authentication required but %s", fail_reason), DEFER,
1132 FALSE);
1133 return DEFER;
1134 }
1135
1136 return OK;
1137 }
1138
1139
1140 /* Construct AUTH appendix string for MAIL TO */
1141 /*
1142 Arguments
1143 buffer to build string
1144 addrlist chain of potential addresses to deliver
1145 ob transport options
1146
1147 Globals smtp_authenticated
1148 client_authenticated_sender
1149 Return True on error, otherwise buffer has (possibly empty) terminated string
1150 */
1151
1152 BOOL
1153 smtp_mail_auth_str(uschar *buffer, unsigned bufsize, address_item *addrlist,
1154 smtp_transport_options_block *ob)
1155 {
1156 uschar *local_authenticated_sender = authenticated_sender;
1157
1158 #ifdef notdef
1159 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n", authenticated_sender, ob->authenticated_sender, smtp_authenticated?"Y":"N");
1160 #endif
1161
1162 if (ob->authenticated_sender != NULL)
1163 {
1164 uschar *new = expand_string(ob->authenticated_sender);
1165 if (new == NULL)
1166 {
1167 if (!expand_string_forcedfail)
1168 {
1169 uschar *message = string_sprintf("failed to expand "
1170 "authenticated_sender: %s", expand_string_message);
1171 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1172 return TRUE;
1173 }
1174 }
1175 else if (new[0] != 0) local_authenticated_sender = new;
1176 }
1177
1178 /* Add the authenticated sender address if present */
1179
1180 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1181 local_authenticated_sender != NULL)
1182 {
1183 string_format(buffer, bufsize, " AUTH=%s",
1184 auth_xtextencode(local_authenticated_sender,
1185 Ustrlen(local_authenticated_sender)));
1186 client_authenticated_sender = string_copy(local_authenticated_sender);
1187 }
1188 else
1189 *buffer= 0;
1190
1191 return FALSE;
1192 }
1193
1194
1195
1196 #ifdef EXPERIMENTAL_DANE
1197 /* Lookup TLSA record for host/port.
1198 Return: OK success with dnssec; DANE mode
1199 DEFER Do not use this host now, may retry later
1200 FAIL_FORCED No TLSA record; DANE not usable
1201 FAIL Do not use this connection
1202 */
1203
1204 int
1205 tlsa_lookup(const host_item * host, dns_answer * dnsa, BOOL dane_required)
1206 {
1207 /* move this out to host.c given the similarity to dns_lookup() ? */
1208 uschar buffer[300];
1209 const uschar * fullname = buffer;
1210
1211 /* TLSA lookup string */
1212 (void)sprintf(CS buffer, "_%d._tcp.%.256s", host->port, host->name);
1213
1214 switch (dns_lookup(dnsa, buffer, T_TLSA, &fullname))
1215 {
1216 case DNS_SUCCEED:
1217 if (!dns_is_secure(dnsa))
1218 {
1219 log_write(0, LOG_MAIN, "DANE error: TLSA lookup not DNSSEC");
1220 return DEFER;
1221 }
1222 return OK;
1223
1224 case DNS_AGAIN:
1225 return DEFER; /* just defer this TLS'd conn */
1226
1227 case DNS_NODATA: /* no TLSA RR for this lookup */
1228 case DNS_NOMATCH: /* no records at all for this lookup */
1229 return dane_required ? FAIL : FAIL_FORCED;
1230
1231 default:
1232 case DNS_FAIL:
1233 return dane_required ? FAIL : DEFER;
1234 }
1235 }
1236 #endif
1237
1238
1239
1240 typedef struct smtp_compare_s
1241 {
1242 uschar *current_sender_address;
1243 struct transport_instance *tblock;
1244 } smtp_compare_t;
1245
1246 /*
1247 Create a unique string that identifies this message, it is based on
1248 sender_address, helo_data and tls_certificate if enabled. */
1249
1250 static uschar *
1251 smtp_local_identity(uschar * sender, struct transport_instance * tblock)
1252 {
1253 address_item * addr1;
1254 uschar * if1 = US"";
1255 uschar * helo1 = US"";
1256 #ifdef SUPPORT_TLS
1257 uschar * tlsc1 = US"";
1258 #endif
1259 uschar * save_sender_address = sender_address;
1260 uschar * local_identity = NULL;
1261 smtp_transport_options_block * ob =
1262 (smtp_transport_options_block *)tblock->options_block;
1263
1264 sender_address = sender;
1265
1266 addr1 = deliver_make_addr (sender, TRUE);
1267 deliver_set_expansions(addr1);
1268
1269 if (ob->interface)
1270 if1 = expand_string(ob->interface);
1271
1272 if (ob->helo_data)
1273 helo1 = expand_string(ob->helo_data);
1274
1275 #ifdef SUPPORT_TLS
1276 if (ob->tls_certificate)
1277 tlsc1 = expand_string(ob->tls_certificate);
1278 local_identity = string_sprintf ("%s^%s^%s", if1, helo1, tlsc1);
1279 #else
1280 local_identity = string_sprintf ("%s^%s", if1, helo1);
1281 #endif
1282
1283 deliver_set_expansions(NULL);
1284 sender_address = save_sender_address;
1285
1286 return local_identity;
1287 }
1288
1289
1290
1291 /* This routine is a callback that is called from transport_check_waiting.
1292 This function will evaluate the incoming message versus the previous
1293 message. If the incoming message is using a different local identity then
1294 we will veto this new message. */
1295
1296 static BOOL
1297 smtp_are_same_identities(uschar * message_id, smtp_compare_t * s_compare)
1298 {
1299 uschar * message_local_identity,
1300 * current_local_identity,
1301 * new_sender_address;
1302
1303 current_local_identity =
1304 smtp_local_identity(s_compare->current_sender_address, s_compare->tblock);
1305
1306 if (!(new_sender_address = deliver_get_sender_address(message_id)))
1307 return 0;
1308
1309 message_local_identity =
1310 smtp_local_identity(new_sender_address, s_compare->tblock);
1311
1312 return Ustrcmp(current_local_identity, message_local_identity) == 0;
1313 }
1314
1315
1316
1317 uschar
1318 ehlo_response(uschar * buf, size_t bsize, uschar checks)
1319 {
1320 #ifdef SUPPORT_TLS
1321 if ( checks & PEER_OFFERED_TLS
1322 && pcre_exec(regex_STARTTLS, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1323 checks &= ~PEER_OFFERED_TLS;
1324 #endif
1325
1326 if ( checks & PEER_OFFERED_IGNQ
1327 && pcre_exec(regex_IGNOREQUOTA, NULL, CS buf, bsize, 0,
1328 PCRE_EOPT, NULL, 0) < 0)
1329 checks &= ~PEER_OFFERED_IGNQ;
1330
1331 if ( checks & PEER_OFFERED_CHUNKING
1332 && pcre_exec(regex_CHUNKING, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1333 checks &= ~PEER_OFFERED_CHUNKING;
1334
1335 #ifndef DISABLE_PRDR
1336 if ( checks & PEER_OFFERED_PRDR
1337 && pcre_exec(regex_PRDR, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1338 checks &= ~PEER_OFFERED_PRDR;
1339 #endif
1340
1341 #ifdef SUPPORT_I18N
1342 if ( checks & PEER_OFFERED_UTF8
1343 && pcre_exec(regex_UTF8, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1344 checks &= ~PEER_OFFERED_UTF8;
1345 #endif
1346
1347 if ( checks & PEER_OFFERED_DSN
1348 && pcre_exec(regex_DSN, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1349 checks &= ~PEER_OFFERED_DSN;
1350
1351 if ( checks & PEER_OFFERED_PIPE
1352 && pcre_exec(regex_PIPELINING, NULL, CS buf, bsize, 0,
1353 PCRE_EOPT, NULL, 0) < 0)
1354 checks &= ~PEER_OFFERED_PIPE;
1355
1356 if ( checks & PEER_OFFERED_SIZE
1357 && pcre_exec(regex_SIZE, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1358 checks &= ~PEER_OFFERED_SIZE;
1359
1360 return checks;
1361 }
1362
1363
1364
1365 /* Callback for emitting a BDAT data chunk header.
1366
1367 If given a nonzero size, first flush any buffered SMTP commands
1368 then emit the command.
1369
1370 Reap previous SMTP command responses if requested.
1371 Reap one SMTP command response if requested.
1372
1373 Returns: OK or ERROR
1374 */
1375
1376 static int
1377 smtp_chunk_cmd_callback(int fd, transport_ctx * tctx,
1378 unsigned chunk_size, unsigned flags)
1379 {
1380 smtp_transport_options_block * ob =
1381 (smtp_transport_options_block *)(tctx->tblock->options_block);
1382 int cmd_count = 0;
1383 int prev_cmd_count;
1384 uschar * buffer = tctx->buffer;
1385
1386
1387 /* Write SMTP chunk header command */
1388
1389 if (chunk_size > 0)
1390 if((cmd_count = smtp_write_command(tctx->outblock, FALSE, "BDAT %u%s\r\n",
1391 chunk_size,
1392 flags & tc_chunk_last ? " LAST" : "")
1393 ) < 0) return ERROR;
1394
1395 prev_cmd_count = cmd_count += tctx->cmd_count;
1396
1397 /* Reap responses for any previous, but not one we just emitted */
1398
1399 if (chunk_size > 0)
1400 prev_cmd_count--;
1401 if (tctx->pending_BDAT)
1402 prev_cmd_count--;
1403
1404 if (flags & tc_reap_prev && prev_cmd_count > 0)
1405 {
1406 DEBUG(D_transport) debug_printf("look for %d responses"
1407 " for previous pipelined cmds\n", prev_cmd_count);
1408
1409 switch(sync_responses(tctx->first_addr, tctx->tblock->rcpt_include_affixes,
1410 tctx->sync_addr, tctx->host, prev_cmd_count,
1411 ob->address_retry_include_sender,
1412 tctx->pending_MAIL, 0,
1413 tctx->inblock,
1414 ob->command_timeout,
1415 buffer, DELIVER_BUFFER_SIZE))
1416 {
1417 case 1: /* 2xx (only) => OK */
1418 case 3: tctx->good_RCPT = TRUE; /* 2xx & 5xx => OK & progress made */
1419 case 2: *tctx->completed_address = TRUE; /* 5xx (only) => progress made */
1420 case 0: break; /* No 2xx or 5xx, but no probs */
1421
1422 case -1: /* Timeout on RCPT */
1423 default: return ERROR; /* I/O error, or any MAIL/DATA error */
1424 }
1425 cmd_count = 1;
1426 if (!tctx->pending_BDAT)
1427 pipelining_active = FALSE;
1428 }
1429
1430 /* Reap response for an outstanding BDAT */
1431
1432 if (tctx->pending_BDAT)
1433 {
1434 DEBUG(D_transport) debug_printf("look for one response for BDAT\n");
1435
1436 if (!smtp_read_response(tctx->inblock, buffer, DELIVER_BUFFER_SIZE, '2',
1437 ob->command_timeout))
1438 {
1439 if (errno == 0 && buffer[0] == '4')
1440 {
1441 errno = ERRNO_DATA4XX; /*XXX does this actually get used? */
1442 tctx->first_addr->more_errno |=
1443 ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1444 }
1445 return ERROR;
1446 }
1447 cmd_count--;
1448 tctx->pending_BDAT = FALSE;
1449 pipelining_active = FALSE;
1450 }
1451 else if (chunk_size > 0)
1452 tctx->pending_BDAT = TRUE;
1453
1454
1455 tctx->cmd_count = cmd_count;
1456 return OK;
1457 }
1458
1459
1460
1461 /*************************************************
1462 * Deliver address list to given host *
1463 *************************************************/
1464
1465 /* If continue_hostname is not null, we get here only when continuing to
1466 deliver down an existing channel. The channel was passed as the standard
1467 input. TLS is never active on a passed channel; the previous process always
1468 closes it down before passing the connection on.
1469
1470 Otherwise, we have to make a connection to the remote host, and do the
1471 initial protocol exchange.
1472
1473 When running as an MUA wrapper, if the sender or any recipient is rejected,
1474 temporarily or permanently, we force failure for all recipients.
1475
1476 Arguments:
1477 addrlist chain of potential addresses to deliver; only those whose
1478 transport_return field is set to PENDING_DEFER are currently
1479 being processed; others should be skipped - they have either
1480 been delivered to an earlier host or IP address, or been
1481 failed by one of them.
1482 host host to deliver to
1483 host_af AF_INET or AF_INET6
1484 port default TCP/IP port to use, in host byte order
1485 interface interface to bind to, or NULL
1486 tblock transport instance block
1487 message_defer set TRUE if yield is OK, but all addresses were deferred
1488 because of a non-recipient, non-host failure, that is, a
1489 4xx response to MAIL FROM, DATA, or ".". This is a defer
1490 that is specific to the message.
1491 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1492 a second attempt after TLS initialization fails
1493
1494 Returns: OK - the connection was made and the delivery attempted;
1495 the result for each address is in its data block.
1496 DEFER - the connection could not be made, or something failed
1497 while setting up the SMTP session, or there was a
1498 non-message-specific error, such as a timeout.
1499 ERROR - a filter command is specified for this transport,
1500 and there was a problem setting it up; OR helo_data
1501 or add_headers or authenticated_sender is specified
1502 for this transport, and the string failed to expand
1503 */
1504
1505 static int
1506 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
1507 uschar *interface, transport_instance *tblock,
1508 BOOL *message_defer, BOOL suppress_tls)
1509 {
1510 address_item *addr;
1511 address_item *sync_addr;
1512 address_item *first_addr = addrlist;
1513 int yield = OK;
1514 int address_count;
1515 int save_errno;
1516 int rc;
1517 time_t start_delivery_time = time(NULL);
1518 smtp_transport_options_block *ob =
1519 (smtp_transport_options_block *)(tblock->options_block);
1520 BOOL lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
1521 BOOL smtps = strcmpic(ob->protocol, US"smtps") == 0;
1522 BOOL ok = FALSE;
1523 BOOL send_rset = TRUE;
1524 BOOL send_quit = TRUE;
1525 BOOL setting_up = TRUE;
1526 BOOL completed_address = FALSE;
1527 BOOL esmtp = TRUE;
1528 BOOL pending_MAIL;
1529 BOOL pass_message = FALSE;
1530 uschar peer_offered = 0;
1531 #ifndef DISABLE_PRDR
1532 BOOL prdr_active;
1533 #endif
1534 #ifdef SUPPORT_I18N
1535 BOOL utf8_needed = FALSE;
1536 #endif
1537 BOOL dsn_all_lasthop = TRUE;
1538 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1539 BOOL dane = FALSE;
1540 BOOL dane_required = verify_check_given_host(&ob->hosts_require_dane, host) == OK;
1541 dns_answer tlsa_dnsa;
1542 #endif
1543 smtp_inblock inblock;
1544 smtp_outblock outblock;
1545 int max_rcpt = tblock->max_addresses;
1546 uschar *igquotstr = US"";
1547
1548 #ifdef EXPERIMENTAL_DSN_INFO
1549 uschar *smtp_greeting = NULL;
1550 uschar *helo_response = NULL;
1551 #endif
1552 uschar *helo_data = NULL;
1553
1554 uschar *message = NULL;
1555 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
1556 uschar *p;
1557 uschar buffer[DELIVER_BUFFER_SIZE];
1558 uschar inbuffer[4096];
1559 uschar outbuffer[4096];
1560
1561 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
1562
1563 *message_defer = FALSE;
1564 smtp_command = US"initial connection";
1565 if (max_rcpt == 0) max_rcpt = 999999;
1566
1567 /* Set up the buffer for reading SMTP response packets. */
1568
1569 inblock.buffer = inbuffer;
1570 inblock.buffersize = sizeof(inbuffer);
1571 inblock.ptr = inbuffer;
1572 inblock.ptrend = inbuffer;
1573
1574 /* Set up the buffer for holding SMTP commands while pipelining */
1575
1576 outblock.buffer = outbuffer;
1577 outblock.buffersize = sizeof(outbuffer);
1578 outblock.ptr = outbuffer;
1579 outblock.cmd_count = 0;
1580 outblock.authenticating = FALSE;
1581
1582 /* Reset the parameters of a TLS session. */
1583
1584 tls_out.bits = 0;
1585 tls_out.cipher = NULL; /* the one we may use for this transport */
1586 tls_out.ourcert = NULL;
1587 tls_out.peercert = NULL;
1588 tls_out.peerdn = NULL;
1589 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1590 tls_out.sni = NULL;
1591 #endif
1592 tls_out.ocsp = OCSP_NOT_REQ;
1593
1594 /* Flip the legacy TLS-related variables over to the outbound set in case
1595 they're used in the context of the transport. Don't bother resetting
1596 afterward as we're in a subprocess. */
1597
1598 tls_modify_variables(&tls_out);
1599
1600 #ifndef SUPPORT_TLS
1601 if (smtps)
1602 {
1603 set_errno_nohost(addrlist, ERRNO_TLSFAILURE, US"TLS support not available",
1604 DEFER, FALSE);
1605 return ERROR;
1606 }
1607 #endif
1608
1609 /* Make a connection to the host if this isn't a continued delivery, and handle
1610 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
1611 specially so they can be identified for retries. */
1612
1613 if (continue_hostname == NULL)
1614 {
1615 /* This puts port into host->port */
1616 inblock.sock = outblock.sock =
1617 smtp_connect(host, host_af, port, interface, ob->connect_timeout, tblock);
1618
1619 if (inblock.sock < 0)
1620 {
1621 set_errno_nohost(addrlist, (errno == ETIMEDOUT)? ERRNO_CONNECTTIMEOUT : errno,
1622 NULL, DEFER, FALSE);
1623 return DEFER;
1624 }
1625
1626 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1627 {
1628 tls_out.dane_verified = FALSE;
1629 tls_out.tlsa_usage = 0;
1630
1631 if (host->dnssec == DS_YES)
1632 {
1633 if( dane_required
1634 || verify_check_given_host(&ob->hosts_try_dane, host) == OK
1635 )
1636 switch (rc = tlsa_lookup(host, &tlsa_dnsa, dane_required))
1637 {
1638 case OK: dane = TRUE; break;
1639 case FAIL_FORCED: break;
1640 default: set_errno_nohost(addrlist, ERRNO_DNSDEFER,
1641 string_sprintf("DANE error: tlsa lookup %s",
1642 rc == DEFER ? "DEFER" : "FAIL"),
1643 rc, FALSE);
1644 return rc;
1645 }
1646 }
1647 else if (dane_required)
1648 {
1649 set_errno_nohost(addrlist, ERRNO_DNSDEFER,
1650 string_sprintf("DANE error: %s lookup not DNSSEC", host->name),
1651 FAIL, FALSE);
1652 return FAIL;
1653 }
1654
1655 if (dane)
1656 ob->tls_tempfail_tryclear = FALSE;
1657 }
1658 #endif /*DANE*/
1659
1660 /* Expand the greeting message while waiting for the initial response. (Makes
1661 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1662 delayed till here so that $sending_interface and $sending_port are set. */
1663
1664 helo_data = expand_string(ob->helo_data);
1665 #ifdef SUPPORT_I18N
1666 if (helo_data)
1667 {
1668 uschar * errstr = NULL;
1669 if ((helo_data = string_domain_utf8_to_alabel(helo_data, &errstr)), errstr)
1670 {
1671 errstr = string_sprintf("failed to expand helo_data: %s", errstr);
1672 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE);
1673 yield = DEFER;
1674 goto SEND_QUIT;
1675 }
1676 }
1677 #endif
1678
1679 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1680 is nevertheless a reasonably clean way of programming this kind of logic,
1681 where you want to escape on any error. */
1682
1683 if (!smtps)
1684 {
1685 BOOL good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
1686 '2', ob->command_timeout);
1687 #ifdef EXPERIMENTAL_DSN_INFO
1688 smtp_greeting = string_copy(buffer);
1689 #endif
1690 if (!good_response) goto RESPONSE_FAILED;
1691
1692 #ifndef DISABLE_EVENT
1693 {
1694 uschar * s;
1695 lookup_dnssec_authenticated = host->dnssec==DS_YES ? US"yes"
1696 : host->dnssec==DS_NO ? US"no" : NULL;
1697 s = event_raise(tblock->event_action, US"smtp:connect", buffer);
1698 if (s)
1699 {
1700 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL,
1701 string_sprintf("deferred by smtp:connect event expansion: %s", s),
1702 DEFER, FALSE);
1703 yield = DEFER;
1704 goto SEND_QUIT;
1705 }
1706 }
1707 #endif
1708
1709 /* Now check if the helo_data expansion went well, and sign off cleanly if
1710 it didn't. */
1711
1712 if (helo_data == NULL)
1713 {
1714 uschar *message = string_sprintf("failed to expand helo_data: %s",
1715 expand_string_message);
1716 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1717 yield = DEFER;
1718 goto SEND_QUIT;
1719 }
1720 }
1721
1722 /** Debugging without sending a message
1723 addrlist->transport_return = DEFER;
1724 goto SEND_QUIT;
1725 **/
1726
1727 /* Errors that occur after this point follow an SMTP command, which is
1728 left in big_buffer by smtp_write_command() for use in error messages. */
1729
1730 smtp_command = big_buffer;
1731
1732 /* Tell the remote who we are...
1733
1734 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1735 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1736 greeting is of this form. The assumption was that the far end supports it
1737 properly... but experience shows that there are some that give 5xx responses,
1738 even though the banner includes "ESMTP" (there's a bloody-minded one that
1739 says "ESMTP not spoken here"). Cope with that case.
1740
1741 September 2000: Time has passed, and it seems reasonable now to always send
1742 EHLO at the start. It is also convenient to make the change while installing
1743 the TLS stuff.
1744
1745 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1746 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1747 would be no way to send out the mails, so there is now a host list
1748 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1749 PIPELINING problem as well. Maybe it can also be useful to cure other
1750 problems with broken servers.
1751
1752 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1753 Then somebody tried it with a Microsoft mailer... It seems that all other
1754 mailers use upper case for some reason (the RFC is quite clear about case
1755 independence) so, for peace of mind, I gave in. */
1756
1757 esmtp = verify_check_given_host(&ob->hosts_avoid_esmtp, host) != OK;
1758
1759 /* Alas; be careful, since this goto is not an error-out, so conceivably
1760 we might set data between here and the target which we assume to exist
1761 and be usable. I can see this coming back to bite us. */
1762 #ifdef SUPPORT_TLS
1763 if (smtps)
1764 {
1765 smtp_peer_options |= PEER_OFFERED_TLS;
1766 suppress_tls = FALSE;
1767 ob->tls_tempfail_tryclear = FALSE;
1768 smtp_command = US"SSL-on-connect";
1769 goto TLS_NEGOTIATE;
1770 }
1771 #endif
1772
1773 if (esmtp)
1774 {
1775 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1776 lmtp? "LHLO" : "EHLO", helo_data) < 0)
1777 goto SEND_FAILED;
1778 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1779 ob->command_timeout))
1780 {
1781 if (errno != 0 || buffer[0] == 0 || lmtp)
1782 {
1783 #ifdef EXPERIMENTAL_DSN_INFO
1784 helo_response = string_copy(buffer);
1785 #endif
1786 goto RESPONSE_FAILED;
1787 }
1788 esmtp = FALSE;
1789 }
1790 #ifdef EXPERIMENTAL_DSN_INFO
1791 helo_response = string_copy(buffer);
1792 #endif
1793 }
1794 else
1795 {
1796 DEBUG(D_transport)
1797 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1798 }
1799
1800 if (!esmtp)
1801 {
1802 BOOL good_response;
1803
1804 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1805 goto SEND_FAILED;
1806 good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
1807 '2', ob->command_timeout);
1808 #ifdef EXPERIMENTAL_DSN_INFO
1809 helo_response = string_copy(buffer);
1810 #endif
1811 if (!good_response) goto RESPONSE_FAILED;
1812 }
1813
1814 peer_offered = smtp_peer_options = 0;
1815
1816 if (esmtp || lmtp)
1817 {
1818 peer_offered = ehlo_response(buffer, Ustrlen(buffer),
1819 PEER_OFFERED_TLS /* others checked later */
1820 );
1821
1822 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1823
1824 #ifdef SUPPORT_TLS
1825 smtp_peer_options |= peer_offered & PEER_OFFERED_TLS;
1826 #endif
1827 }
1828 }
1829
1830 /* For continuing deliveries down the same channel, the socket is the standard
1831 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1832 below). Set up the pointer to where subsequent commands will be left, for
1833 error messages. Note that smtp_peer_options will have been
1834 set from the command line if they were set in the process that passed the
1835 connection on. */
1836
1837 /*XXX continue case needs to propagate DSN_INFO, prob. in deliver.c
1838 as the contine goes via transport_pass_socket() and doublefork and exec.
1839 It does not wait. Unclear how we keep separate host's responses
1840 separate - we could match up by host ip+port as a bodge. */
1841
1842 else
1843 {
1844 inblock.sock = outblock.sock = fileno(stdin);
1845 smtp_command = big_buffer;
1846 host->port = port; /* Record the port that was used */
1847 }
1848
1849 /* If TLS is available on this connection, whether continued or not, attempt to
1850 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1851 send another EHLO - the server may give a different answer in secure mode. We
1852 use a separate buffer for reading the response to STARTTLS so that if it is
1853 negative, the original EHLO data is available for subsequent analysis, should
1854 the client not be required to use TLS. If the response is bad, copy the buffer
1855 for error analysis. */
1856
1857 #ifdef SUPPORT_TLS
1858 if ( smtp_peer_options & PEER_OFFERED_TLS
1859 && !suppress_tls
1860 && verify_check_given_host(&ob->hosts_avoid_tls, host) != OK)
1861 {
1862 uschar buffer2[4096];
1863 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1864 goto SEND_FAILED;
1865
1866 /* If there is an I/O error, transmission of this message is deferred. If
1867 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1868 false, we also defer. However, if there is a temporary rejection of STARTTLS
1869 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1870 STARTTLS, we carry on. This means we will try to send the message in clear,
1871 unless the host is in hosts_require_tls (tested below). */
1872
1873 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1874 ob->command_timeout))
1875 {
1876 if ( errno != 0
1877 || buffer2[0] == 0
1878 || (buffer2[0] == '4' && !ob->tls_tempfail_tryclear)
1879 )
1880 {
1881 Ustrncpy(buffer, buffer2, sizeof(buffer));
1882 goto RESPONSE_FAILED;
1883 }
1884 }
1885
1886 /* STARTTLS accepted: try to negotiate a TLS session. */
1887
1888 else
1889 TLS_NEGOTIATE:
1890 {
1891 int rc = tls_client_start(inblock.sock, host, addrlist, tblock
1892 # ifdef EXPERIMENTAL_DANE
1893 , dane ? &tlsa_dnsa : NULL
1894 # endif
1895 );
1896
1897 /* TLS negotiation failed; give an error. From outside, this function may
1898 be called again to try in clear on a new connection, if the options permit
1899 it for this host. */
1900
1901 if (rc != OK)
1902 {
1903 # ifdef EXPERIMENTAL_DANE
1904 if (rc == DEFER && dane)
1905 {
1906 log_write(0, LOG_MAIN,
1907 "DANE attempt failed; no TLS connection to %s [%s]",
1908 host->name, host->address);
1909 }
1910 # endif
1911
1912 save_errno = ERRNO_TLSFAILURE;
1913 message = US"failure while setting up TLS session";
1914 send_quit = FALSE;
1915 goto TLS_FAILED;
1916 }
1917
1918 /* TLS session is set up */
1919
1920 smtp_peer_options_wrap = smtp_peer_options;
1921 for (addr = addrlist; addr; addr = addr->next)
1922 if (addr->transport_return == PENDING_DEFER)
1923 {
1924 addr->cipher = tls_out.cipher;
1925 addr->ourcert = tls_out.ourcert;
1926 addr->peercert = tls_out.peercert;
1927 addr->peerdn = tls_out.peerdn;
1928 addr->ocsp = tls_out.ocsp;
1929 }
1930 }
1931 }
1932
1933 /* if smtps, we'll have smtp_command set to something else; always safe to
1934 reset it here. */
1935 smtp_command = big_buffer;
1936
1937 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1938 helo_data is null, we are dealing with a connection that was passed from
1939 another process, and so we won't have expanded helo_data above. We have to
1940 expand it here. $sending_ip_address and $sending_port are set up right at the
1941 start of the Exim process (in exim.c). */
1942
1943 if (tls_out.active >= 0)
1944 {
1945 char *greeting_cmd;
1946 BOOL good_response;
1947
1948 if (helo_data == NULL)
1949 {
1950 helo_data = expand_string(ob->helo_data);
1951 if (helo_data == NULL)
1952 {
1953 uschar *message = string_sprintf("failed to expand helo_data: %s",
1954 expand_string_message);
1955 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1956 yield = DEFER;
1957 goto SEND_QUIT;
1958 }
1959 }
1960
1961 /* For SMTPS we need to wait for the initial OK response. */
1962 if (smtps)
1963 {
1964 good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
1965 '2', ob->command_timeout);
1966 #ifdef EXPERIMENTAL_DSN_INFO
1967 smtp_greeting = string_copy(buffer);
1968 #endif
1969 if (!good_response) goto RESPONSE_FAILED;
1970 }
1971
1972 if (esmtp)
1973 greeting_cmd = "EHLO";
1974 else
1975 {
1976 greeting_cmd = "HELO";
1977 DEBUG(D_transport)
1978 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1979 }
1980
1981 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1982 lmtp? "LHLO" : greeting_cmd, helo_data) < 0)
1983 goto SEND_FAILED;
1984 good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
1985 '2', ob->command_timeout);
1986 #ifdef EXPERIMENTAL_DSN_INFO
1987 helo_response = string_copy(buffer);
1988 #endif
1989 if (!good_response) goto RESPONSE_FAILED;
1990 smtp_peer_options = 0;
1991 }
1992
1993 /* If the host is required to use a secure channel, ensure that we
1994 have one. */
1995
1996 else if ( smtps
1997 # ifdef EXPERIMENTAL_DANE
1998 || dane
1999 # endif
2000 || verify_check_given_host(&ob->hosts_require_tls, host) == OK
2001 )
2002 {
2003 save_errno = ERRNO_TLSREQUIRED;
2004 message = string_sprintf("a TLS session is required, but %s",
2005 smtp_peer_options & PEER_OFFERED_TLS
2006 ? "an attempt to start TLS failed" : "the server did not offer TLS support");
2007 goto TLS_FAILED;
2008 }
2009 #endif /*SUPPORT_TLS*/
2010
2011 /* If TLS is active, we have just started it up and re-done the EHLO command,
2012 so its response needs to be analyzed. If TLS is not active and this is a
2013 continued session down a previously-used socket, we haven't just done EHLO, so
2014 we skip this. */
2015
2016 if (continue_hostname == NULL
2017 #ifdef SUPPORT_TLS
2018 || tls_out.active >= 0
2019 #endif
2020 )
2021 {
2022 if (esmtp || lmtp)
2023 {
2024 peer_offered = ehlo_response(buffer, Ustrlen(buffer),
2025 0 /* no TLS */
2026 | (lmtp && ob->lmtp_ignore_quota ? PEER_OFFERED_IGNQ : 0)
2027 | PEER_OFFERED_CHUNKING
2028 | PEER_OFFERED_PRDR
2029 #ifdef SUPPORT_I18N
2030 | (addrlist->prop.utf8_msg ? PEER_OFFERED_UTF8 : 0)
2031 /*XXX if we hand peercaps on to continued-conn processes,
2032 must not depend on this addr */
2033 #endif
2034 | PEER_OFFERED_DSN
2035 | PEER_OFFERED_PIPE
2036 | (ob->size_addition >= 0 ? PEER_OFFERED_SIZE : 0)
2037 );
2038
2039 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
2040 lmtp_ignore_quota option was set. */
2041
2042 igquotstr = peer_offered & PEER_OFFERED_IGNQ ? US" IGNOREQUOTA" : US"";
2043
2044 /* If the response to EHLO specified support for the SIZE parameter, note
2045 this, provided size_addition is non-negative. */
2046
2047 smtp_peer_options |= peer_offered & PEER_OFFERED_SIZE;
2048
2049 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
2050 the current host, esmtp will be false, so PIPELINING can never be used. If
2051 the current host matches hosts_avoid_pipelining, don't do it. */
2052
2053 if ( peer_offered & PEER_OFFERED_PIPE
2054 && verify_check_given_host(&ob->hosts_avoid_pipelining, host) != OK)
2055 smtp_peer_options |= PEER_OFFERED_PIPE;
2056
2057 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
2058 smtp_peer_options & PEER_OFFERED_PIPE ? "" : "not ");
2059
2060 if ( peer_offered & PEER_OFFERED_CHUNKING
2061 && verify_check_given_host(&ob->hosts_try_chunking, host) != OK)
2062 peer_offered &= ~PEER_OFFERED_CHUNKING;
2063
2064 if (peer_offered & PEER_OFFERED_CHUNKING)
2065 {DEBUG(D_transport) debug_printf("CHUNKING usable\n");}
2066
2067 #ifndef DISABLE_PRDR
2068 if ( peer_offered & PEER_OFFERED_PRDR
2069 && verify_check_given_host(&ob->hosts_try_prdr, host) != OK)
2070 peer_offered &= ~PEER_OFFERED_PRDR;
2071
2072 if (peer_offered & PEER_OFFERED_PRDR)
2073 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
2074 #endif
2075
2076 /* Note if the server supports DSN */
2077 smtp_peer_options |= peer_offered & PEER_OFFERED_DSN;
2078 DEBUG(D_transport) debug_printf("%susing DSN\n",
2079 peer_offered & PEER_OFFERED_DSN ? "" : "not ");
2080
2081 /* Note if the response to EHLO specifies support for the AUTH extension.
2082 If it has, check that this host is one we want to authenticate to, and do
2083 the business. The host name and address must be available when the
2084 authenticator's client driver is running. */
2085
2086 switch (yield = smtp_auth(buffer, sizeof(buffer), addrlist, host,
2087 ob, esmtp, &inblock, &outblock))
2088 {
2089 default: goto SEND_QUIT;
2090 case OK: break;
2091 case FAIL_SEND: goto SEND_FAILED;
2092 case FAIL: goto RESPONSE_FAILED;
2093 }
2094 }
2095 }
2096 pipelining_active = !!(smtp_peer_options & PEER_OFFERED_PIPE);
2097
2098 /* The setting up of the SMTP call is now complete. Any subsequent errors are
2099 message-specific. */
2100
2101 setting_up = FALSE;
2102
2103 #ifdef SUPPORT_I18N
2104 if (addrlist->prop.utf8_msg)
2105 {
2106 utf8_needed = !addrlist->prop.utf8_downcvt
2107 && !addrlist->prop.utf8_downcvt_maybe;
2108 DEBUG(D_transport) if (!utf8_needed) debug_printf("utf8: %s downconvert\n",
2109 addrlist->prop.utf8_downcvt ? "mandatory" : "optional");
2110 }
2111
2112 /* If this is an international message we need the host to speak SMTPUTF8 */
2113 if (utf8_needed && !(peer_offered & PEER_OFFERED_UTF8))
2114 {
2115 errno = ERRNO_UTF8_FWD;
2116 goto RESPONSE_FAILED;
2117 }
2118 #endif
2119
2120 /* If there is a filter command specified for this transport, we can now
2121 set it up. This cannot be done until the identify of the host is known. */
2122
2123 if (tblock->filter_command != NULL)
2124 {
2125 BOOL rc;
2126 uschar buffer[64];
2127 sprintf(CS buffer, "%.50s transport", tblock->name);
2128 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
2129 TRUE, DEFER, addrlist, buffer, NULL);
2130 transport_filter_timeout = tblock->filter_timeout;
2131
2132 /* On failure, copy the error to all addresses, abandon the SMTP call, and
2133 yield ERROR. */
2134
2135 if (!rc)
2136 {
2137 set_errno_nohost(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
2138 FALSE);
2139 yield = ERROR;
2140 goto SEND_QUIT;
2141 }
2142
2143 if ( transport_filter_argv
2144 && *transport_filter_argv
2145 && **transport_filter_argv
2146 && peer_offered & PEER_OFFERED_CHUNKING
2147 )
2148 {
2149 peer_offered &= ~PEER_OFFERED_CHUNKING;
2150 DEBUG(D_transport) debug_printf("CHUNKING not usable due to transport filter\n");
2151 }
2152 }
2153
2154
2155 /* For messages that have more than the maximum number of envelope recipients,
2156 we want to send several transactions down the same SMTP connection. (See
2157 comments in deliver.c as to how this reconciles, heuristically, with
2158 remote_max_parallel.) This optimization was added to Exim after the following
2159 code was already working. The simplest way to put it in without disturbing the
2160 code was to use a goto to jump back to this point when there is another
2161 transaction to handle. */
2162
2163 SEND_MESSAGE:
2164 sync_addr = first_addr;
2165 address_count = 0;
2166 ok = FALSE;
2167 send_rset = TRUE;
2168 completed_address = FALSE;
2169
2170
2171 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
2172 qualification, send it, adding something to the message size to allow for
2173 imprecision and things that get added en route. Exim keeps the number of lines
2174 in a message, so we can give an accurate value for the original message, but we
2175 need some additional to handle added headers. (Double "." characters don't get
2176 included in the count.) */
2177
2178 p = buffer;
2179 *p = 0;
2180
2181 if (peer_offered & PEER_OFFERED_SIZE)
2182 {
2183 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
2184 while (*p) p++;
2185 }
2186
2187 #ifndef DISABLE_PRDR
2188 prdr_active = FALSE;
2189 if (peer_offered & PEER_OFFERED_PRDR)
2190 for (addr = first_addr; addr; addr = addr->next)
2191 if (addr->transport_return == PENDING_DEFER)
2192 {
2193 for (addr = addr->next; addr; addr = addr->next)
2194 if (addr->transport_return == PENDING_DEFER)
2195 { /* at least two recipients to send */
2196 prdr_active = TRUE;
2197 sprintf(CS p, " PRDR"); p += 5;
2198 break;
2199 }
2200 break;
2201 }
2202 #endif
2203
2204 #ifdef SUPPORT_I18N
2205 if ( addrlist->prop.utf8_msg
2206 && !addrlist->prop.utf8_downcvt
2207 && peer_offered & PEER_OFFERED_UTF8
2208 )
2209 sprintf(CS p, " SMTPUTF8"), p += 9;
2210 #endif
2211
2212 /* check if all addresses have lasthop flag */
2213 /* do not send RET and ENVID if true */
2214 for (dsn_all_lasthop = TRUE, addr = first_addr;
2215 address_count < max_rcpt && addr != NULL;
2216 addr = addr->next)
2217 if ((addr->dsn_flags & rf_dsnlasthop) != 1)
2218 {
2219 dsn_all_lasthop = FALSE;
2220 break;
2221 }
2222
2223 /* Add any DSN flags to the mail command */
2224
2225 if (peer_offered & PEER_OFFERED_DSN && !dsn_all_lasthop)
2226 {
2227 if (dsn_ret == dsn_ret_hdrs)
2228 { Ustrcpy(p, " RET=HDRS"); p += 9; }
2229 else if (dsn_ret == dsn_ret_full)
2230 { Ustrcpy(p, " RET=FULL"); p += 9; }
2231
2232 if (dsn_envid)
2233 {
2234 string_format(p, sizeof(buffer) - (p-buffer), " ENVID=%s", dsn_envid);
2235 while (*p) p++;
2236 }
2237 }
2238
2239 /* If an authenticated_sender override has been specified for this transport
2240 instance, expand it. If the expansion is forced to fail, and there was already
2241 an authenticated_sender for this message, the original value will be used.
2242 Other expansion failures are serious. An empty result is ignored, but there is
2243 otherwise no check - this feature is expected to be used with LMTP and other
2244 cases where non-standard addresses (e.g. without domains) might be required. */
2245
2246 if (smtp_mail_auth_str(p, sizeof(buffer) - (p-buffer), addrlist, ob))
2247 {
2248 yield = ERROR;
2249 goto SEND_QUIT;
2250 }
2251
2252 /* From here until we send the DATA command, we can make use of PIPELINING
2253 if the server host supports it. The code has to be able to check the responses
2254 at any point, for when the buffer fills up, so we write it totally generally.
2255 When PIPELINING is off, each command written reports that it has flushed the
2256 buffer. */
2257
2258 pending_MAIL = TRUE; /* The block starts with MAIL */
2259
2260 {
2261 uschar * s = return_path;
2262 #ifdef SUPPORT_I18N
2263 uschar * errstr = NULL;
2264
2265 /* If we must downconvert, do the from-address here. Remember we had to
2266 for the to-addresses (done below), and also (ugly) for re-doing when building
2267 the delivery log line. */
2268
2269 if ( addrlist->prop.utf8_msg
2270 && (addrlist->prop.utf8_downcvt || !(peer_offered & PEER_OFFERED_UTF8))
2271 )
2272 {
2273 if (s = string_address_utf8_to_alabel(return_path, &errstr), errstr)
2274 {
2275 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE);
2276 yield = ERROR;
2277 goto SEND_QUIT;
2278 }
2279 setflag(addrlist, af_utf8_downcvt);
2280 }
2281 #endif
2282
2283 rc = smtp_write_command(&outblock, pipelining_active,
2284 "MAIL FROM:<%s>%s\r\n", s, buffer);
2285 }
2286
2287 mail_command = string_copy(big_buffer); /* Save for later error message */
2288
2289 switch(rc)
2290 {
2291 case -1: /* Transmission error */
2292 goto SEND_FAILED;
2293
2294 case +1: /* Block was sent */
2295 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2296 ob->command_timeout))
2297 {
2298 if (errno == 0 && buffer[0] == '4')
2299 {
2300 errno = ERRNO_MAIL4XX;
2301 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2302 }
2303 goto RESPONSE_FAILED;
2304 }
2305 pending_MAIL = FALSE;
2306 break;
2307 }
2308
2309 /* Pass over all the relevant recipient addresses for this host, which are the
2310 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
2311 several before we have to read the responses for those seen so far. This
2312 checking is done by a subroutine because it also needs to be done at the end.
2313 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
2314 the next one if not all are sent.
2315
2316 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
2317 last address because we want to abort if any recipients have any kind of
2318 problem, temporary or permanent. We know that all recipient addresses will have
2319 the PENDING_DEFER status, because only one attempt is ever made, and we know
2320 that max_rcpt will be large, so all addresses will be done at once. */
2321
2322 for (addr = first_addr;
2323 addr && address_count < max_rcpt;
2324 addr = addr->next)
2325 if (addr->transport_return == PENDING_DEFER)
2326 {
2327 int count;
2328 BOOL no_flush;
2329 uschar * rcpt_addr;
2330
2331 addr->dsn_aware = peer_offered & PEER_OFFERED_DSN
2332 ? dsn_support_yes : dsn_support_no;
2333
2334 address_count++;
2335 no_flush = pipelining_active && (!mua_wrapper || addr->next);
2336
2337 /* Add any DSN flags to the rcpt command and add to the sent string */
2338
2339 p = buffer;
2340 *p = 0;
2341
2342 if (peer_offered & PEER_OFFERED_DSN && !(addr->dsn_flags & rf_dsnlasthop))
2343 {
2344 if (addr->dsn_flags & rf_dsnflags)
2345 {
2346 int i;
2347 BOOL first = TRUE;
2348 Ustrcpy(p, " NOTIFY=");
2349 while (*p) p++;
2350 for (i = 0; i < 4; i++)
2351 if ((addr->dsn_flags & rf_list[i]) != 0)
2352 {
2353 if (!first) *p++ = ',';
2354 first = FALSE;
2355 Ustrcpy(p, rf_names[i]);
2356 while (*p) p++;
2357 }
2358 }
2359
2360 if (addr->dsn_orcpt)
2361 {
2362 string_format(p, sizeof(buffer) - (p-buffer), " ORCPT=%s",
2363 addr->dsn_orcpt);
2364 while (*p) p++;
2365 }
2366 }
2367
2368 /* Now send the RCPT command, and process outstanding responses when
2369 necessary. After a timeout on RCPT, we just end the function, leaving the
2370 yield as OK, because this error can often mean that there is a problem with
2371 just one address, so we don't want to delay the host. */
2372
2373 rcpt_addr = transport_rcpt_address(addr, tblock->rcpt_include_affixes);
2374
2375 #ifdef SUPPORT_I18N
2376 {
2377 uschar * dummy_errstr;
2378 if ( testflag(addrlist, af_utf8_downcvt)
2379 && (rcpt_addr = string_address_utf8_to_alabel(rcpt_addr, &dummy_errstr),
2380 dummy_errstr
2381 ) )
2382 {
2383 errno = ERRNO_EXPANDFAIL;
2384 goto SEND_FAILED;
2385 }
2386 }
2387 #endif
2388
2389 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s%s\r\n",
2390 rcpt_addr, igquotstr, buffer);
2391
2392 if (count < 0) goto SEND_FAILED;
2393 if (count > 0)
2394 {
2395 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
2396 &sync_addr, host, count, ob->address_retry_include_sender,
2397 pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
2398 sizeof(buffer)))
2399 {
2400 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2401 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2402 break;
2403
2404 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2405 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2406 case 0: /* No 2xx or 5xx, but no probs */
2407 break;
2408
2409 case -1: goto END_OFF; /* Timeout on RCPT */
2410 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
2411 }
2412 pending_MAIL = FALSE; /* Dealt with MAIL */
2413 }
2414 } /* Loop for next address */
2415
2416 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
2417 permanently or temporarily. We should have flushed and synced after the last
2418 RCPT. */
2419
2420 if (mua_wrapper)
2421 {
2422 address_item *badaddr;
2423 for (badaddr = first_addr; badaddr; badaddr = badaddr->next)
2424 if (badaddr->transport_return != PENDING_OK)
2425 {
2426 /*XXX could we find a better errno than 0 here? */
2427 set_errno_nohost(addrlist, 0, badaddr->message, FAIL,
2428 testflag(badaddr, af_pass_message));
2429 ok = FALSE;
2430 break;
2431 }
2432 }
2433
2434 /* If ok is TRUE, we know we have got at least one good recipient, and must now
2435 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
2436 have a good recipient buffered up if we are pipelining. We don't want to waste
2437 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
2438 are pipelining. The responses are all handled by sync_responses().
2439 If using CHUNKING, do not send a BDAT until we know how big a chunk we want
2440 to send is. */
2441
2442 if ( !(peer_offered & PEER_OFFERED_CHUNKING)
2443 && (ok || (pipelining_active && !mua_wrapper)))
2444 {
2445 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
2446
2447 if (count < 0) goto SEND_FAILED;
2448 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
2449 host, count, ob->address_retry_include_sender, pending_MAIL,
2450 ok ? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
2451 {
2452 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2453 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2454 break;
2455
2456 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2457 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2458 case 0: break; /* No 2xx or 5xx, but no probs */
2459
2460 case -1: goto END_OFF; /* Timeout on RCPT */
2461 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2462 }
2463 pipelining_active = FALSE;
2464 }
2465
2466 /* If there were no good recipients (but otherwise there have been no
2467 problems), just set ok TRUE, since we have handled address-specific errors
2468 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
2469 for handling the SMTP dot-handling protocol, flagging to apply to headers as
2470 well as body. Set the appropriate timeout value to be used for each chunk.
2471 (Haven't been able to make it work using select() for writing yet.) */
2472
2473 if (!(peer_offered & PEER_OFFERED_CHUNKING) && !ok)
2474 {
2475 /* Save the first address of the next batch. */
2476 first_addr = addr;
2477
2478 ok = TRUE;
2479 }
2480 else
2481 {
2482 transport_ctx tctx = {
2483 tblock,
2484 addrlist,
2485 US".", US"..", /* Escaping strings */
2486 topt_use_crlf | topt_escape_headers
2487 | (tblock->body_only ? topt_no_headers : 0)
2488 | (tblock->headers_only ? topt_no_body : 0)
2489 | (tblock->return_path_add ? topt_add_return_path : 0)
2490 | (tblock->delivery_date_add ? topt_add_delivery_date : 0)
2491 | (tblock->envelope_to_add ? topt_add_envelope_to : 0)
2492 };
2493
2494 /* If using CHUNKING we need a callback from the generic transport
2495 support to us, for the sending of BDAT smtp commands and the reaping
2496 of responses. The callback needs a whole bunch of state so set up
2497 a transport-context structure to be passed around. */
2498
2499 if (peer_offered & PEER_OFFERED_CHUNKING)
2500 {
2501 tctx.check_string = tctx.escape_string = NULL;
2502 tctx.options |= topt_use_bdat;
2503 tctx.chunk_cb = smtp_chunk_cmd_callback;
2504 tctx.inblock = &inblock;
2505 tctx.outblock = &outblock;
2506 tctx.host = host;
2507 tctx.first_addr = first_addr;
2508 tctx.sync_addr = &sync_addr;
2509 tctx.pending_MAIL = pending_MAIL;
2510 tctx.pending_BDAT = FALSE;
2511 tctx.good_RCPT = ok;
2512 tctx.completed_address = &completed_address;
2513 tctx.cmd_count = 0;
2514 tctx.buffer = buffer;
2515 }
2516 else
2517 tctx.options |= topt_end_dot;
2518
2519 /* Save the first address of the next batch. */
2520 first_addr = addr;
2521
2522 /* Responses from CHUNKING commands go in buffer. Otherwise,
2523 there has not been a response. */
2524
2525 buffer[0] = 0;
2526
2527 sigalrm_seen = FALSE;
2528 transport_write_timeout = ob->data_timeout;
2529 smtp_command = US"sending data block"; /* For error messages */
2530 DEBUG(D_transport|D_v)
2531 if (peer_offered & PEER_OFFERED_CHUNKING)
2532 debug_printf(" will write message using CHUNKING\n");
2533 else
2534 debug_printf(" SMTP>> writing message and terminating \".\"\n");
2535 transport_count = 0;
2536
2537 #ifndef DISABLE_DKIM
2538 ok = dkim_transport_write_message(inblock.sock, &tctx, &ob->dkim);
2539 #else
2540 ok = transport_write_message(inblock.sock, &tctx, 0);
2541 #endif
2542
2543 /* transport_write_message() uses write() because it is called from other
2544 places to write to non-sockets. This means that under some OS (e.g. Solaris)
2545 it can exit with "Broken pipe" as its error. This really means that the
2546 socket got closed at the far end. */
2547
2548 transport_write_timeout = 0; /* for subsequent transports */
2549
2550 /* Failure can either be some kind of I/O disaster (including timeout),
2551 or the failure of a transport filter or the expansion of added headers.
2552 Or, when CHUNKING, it can be a protocol-detected failure. */
2553
2554 if (!ok)
2555 goto RESPONSE_FAILED;
2556
2557 /* We used to send the terminating "." explicitly here, but because of
2558 buffering effects at both ends of TCP/IP connections, you don't gain
2559 anything by keeping it separate, so it might as well go in the final
2560 data buffer for efficiency. This is now done by setting the topt_end_dot
2561 flag above. */
2562
2563 smtp_command = US"end of data";
2564
2565 if (peer_offered & PEER_OFFERED_CHUNKING && tctx.cmd_count > 1)
2566 {
2567 /* Reap any outstanding MAIL & RCPT commands, but not a DATA-go-ahead */
2568 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
2569 host, tctx.cmd_count-1, ob->address_retry_include_sender,
2570 pending_MAIL, 0,
2571 &inblock, ob->command_timeout, buffer, sizeof(buffer)))
2572 {
2573 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2574 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2575 break;
2576
2577 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2578 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2579 case 0: break; /* No 2xx or 5xx, but no probs */
2580
2581 case -1: goto END_OFF; /* Timeout on RCPT */
2582 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2583 }
2584 }
2585
2586 #ifndef DISABLE_PRDR
2587 /* For PRDR we optionally get a partial-responses warning
2588 * followed by the individual responses, before going on with
2589 * the overall response. If we don't get the warning then deal
2590 * with per non-PRDR. */
2591 if(prdr_active)
2592 {
2593 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '3',
2594 ob->final_timeout);
2595 if (!ok && errno == 0) switch(buffer[0])
2596 {
2597 case '2': prdr_active = FALSE;
2598 ok = TRUE;
2599 break;
2600 case '4': errno = ERRNO_DATA4XX;
2601 addrlist->more_errno |=
2602 ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2603 break;
2604 }
2605 }
2606 else
2607 #endif
2608
2609 /* For non-PRDR SMTP, we now read a single response that applies to the
2610 whole message. If it is OK, then all the addresses have been delivered. */
2611
2612 if (!lmtp)
2613 {
2614 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2615 ob->final_timeout);
2616 if (!ok && errno == 0 && buffer[0] == '4')
2617 {
2618 errno = ERRNO_DATA4XX;
2619 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2620 }
2621 }
2622
2623 /* For LMTP, we get back a response for every RCPT command that we sent;
2624 some may be accepted and some rejected. For those that get a response, their
2625 status is fixed; any that are accepted have been handed over, even if later
2626 responses crash - at least, that's how I read RFC 2033.
2627
2628 If all went well, mark the recipient addresses as completed, record which
2629 host/IPaddress they were delivered to, and cut out RSET when sending another
2630 message down the same channel. Write the completed addresses to the journal
2631 now so that they are recorded in case there is a crash of hardware or
2632 software before the spool gets updated. Also record the final SMTP
2633 confirmation if needed (for SMTP only). */
2634
2635 if (ok)
2636 {
2637 int flag = '=';
2638 int delivery_time = (int)(time(NULL) - start_delivery_time);
2639 int len;
2640 uschar *conf = NULL;
2641
2642 send_rset = FALSE;
2643 pipelining_active = FALSE;
2644
2645 /* Set up confirmation if needed - applies only to SMTP */
2646
2647 if (
2648 #ifdef DISABLE_EVENT
2649 LOGGING(smtp_confirmation) &&
2650 #endif
2651 !lmtp
2652 )
2653 {
2654 const uschar *s = string_printing(buffer);
2655 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
2656 conf = (s == buffer)? (uschar *)string_copy(s) : US s;
2657 }
2658
2659 /* Process all transported addresses - for LMTP or PRDR, read a status for
2660 each one. */
2661
2662 for (addr = addrlist; addr != first_addr; addr = addr->next)
2663 {
2664 if (addr->transport_return != PENDING_OK) continue;
2665
2666 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
2667 remaining addresses. Otherwise, it's a return code for just the one
2668 address. For temporary errors, add a retry item for the address so that
2669 it doesn't get tried again too soon. */
2670
2671 #ifndef DISABLE_PRDR
2672 if (lmtp || prdr_active)
2673 #else
2674 if (lmtp)
2675 #endif
2676 {
2677 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2678 ob->final_timeout))
2679 {
2680 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
2681 addr->message = string_sprintf(
2682 #ifndef DISABLE_PRDR
2683 "%s error after %s: %s", prdr_active ? "PRDR":"LMTP",
2684 #else
2685 "LMTP error after %s: %s",
2686 #endif
2687 big_buffer, string_printing(buffer));
2688 setflag(addr, af_pass_message); /* Allow message to go to user */
2689 if (buffer[0] == '5')
2690 addr->transport_return = FAIL;
2691 else
2692 {
2693 errno = ERRNO_DATA4XX;
2694 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2695 addr->transport_return = DEFER;
2696 #ifndef DISABLE_PRDR
2697 if (!prdr_active)
2698 #endif
2699 retry_add_item(addr, addr->address_retry_key, 0);
2700 }
2701 continue;
2702 }
2703 completed_address = TRUE; /* NOW we can set this flag */
2704 if (LOGGING(smtp_confirmation))
2705 {
2706 const uschar *s = string_printing(buffer);
2707 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
2708 conf = (s == buffer)? (uschar *)string_copy(s) : US s;
2709 }
2710 }
2711
2712 /* SMTP, or success return from LMTP for this address. Pass back the
2713 actual host that was used. */
2714
2715 addr->transport_return = OK;
2716 addr->more_errno = delivery_time;
2717 addr->host_used = host;
2718 addr->special_action = flag;
2719 addr->message = conf;
2720 #ifndef DISABLE_PRDR
2721 if (prdr_active) addr->flags |= af_prdr_used;
2722 #endif
2723 if (peer_offered & PEER_OFFERED_CHUNKING) addr->flags |= af_chunking_used;
2724 flag = '-';
2725
2726 #ifndef DISABLE_PRDR
2727 if (!prdr_active)
2728 #endif
2729 {
2730 /* Update the journal. For homonymic addresses, use the base address plus
2731 the transport name. See lots of comments in deliver.c about the reasons
2732 for the complications when homonyms are involved. Just carry on after
2733 write error, as it may prove possible to update the spool file later. */
2734
2735 if (testflag(addr, af_homonym))
2736 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2737 else
2738 sprintf(CS buffer, "%.500s\n", addr->unique);
2739
2740 DEBUG(D_deliver) debug_printf("journalling %s\n", buffer);
2741 len = Ustrlen(CS buffer);
2742 if (write(journal_fd, buffer, len) != len)
2743 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2744 "%s: %s", buffer, strerror(errno));
2745 }
2746 }
2747
2748 #ifndef DISABLE_PRDR
2749 if (prdr_active)
2750 {
2751 /* PRDR - get the final, overall response. For any non-success
2752 upgrade all the address statuses. */
2753 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2754 ob->final_timeout);
2755 if (!ok)
2756 {
2757 if(errno == 0 && buffer[0] == '4')
2758 {
2759 errno = ERRNO_DATA4XX;
2760 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2761 }
2762 for (addr = addrlist; addr != first_addr; addr = addr->next)
2763 if (buffer[0] == '5' || addr->transport_return == OK)
2764 addr->transport_return = PENDING_OK; /* allow set_errno action */
2765 goto RESPONSE_FAILED;
2766 }
2767
2768 /* Update the journal, or setup retry. */
2769 for (addr = addrlist; addr != first_addr; addr = addr->next)
2770 if (addr->transport_return == OK)
2771 {
2772 if (testflag(addr, af_homonym))
2773 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2774 else
2775 sprintf(CS buffer, "%.500s\n", addr->unique);
2776
2777 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s\n", buffer);
2778 len = Ustrlen(CS buffer);
2779 if (write(journal_fd, buffer, len) != len)
2780 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2781 "%s: %s", buffer, strerror(errno));
2782 }
2783 else if (addr->transport_return == DEFER)
2784 retry_add_item(addr, addr->address_retry_key, -2);
2785 }
2786 #endif
2787
2788 /* Ensure the journal file is pushed out to disk. */
2789
2790 if (EXIMfsync(journal_fd) < 0)
2791 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
2792 strerror(errno));
2793 }
2794 }
2795
2796
2797 /* Handle general (not specific to one address) failures here. The value of ok
2798 is used to skip over this code on the falling through case. A timeout causes a
2799 deferral. Other errors may defer or fail according to the response code, and
2800 may set up a special errno value, e.g. after connection chopped, which is
2801 assumed if errno == 0 and there is no text in the buffer. If control reaches
2802 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
2803 the problem is not related to this specific message. */
2804
2805 if (!ok)
2806 {
2807 int code, set_rc;
2808 uschar * set_message;
2809
2810 RESPONSE_FAILED:
2811 {
2812 save_errno = errno;
2813 message = NULL;
2814 send_quit = check_response(host, &save_errno, addrlist->more_errno,
2815 buffer, &code, &message, &pass_message);
2816 goto FAILED;
2817 }
2818
2819 SEND_FAILED:
2820 {
2821 save_errno = errno;
2822 code = '4';
2823 message = US string_sprintf("send() to %s [%s] failed: %s",
2824 host->name, host->address, strerror(save_errno));
2825 send_quit = FALSE;
2826 goto FAILED;
2827 }
2828
2829 /* This label is jumped to directly when a TLS negotiation has failed,
2830 or was not done for a host for which it is required. Values will be set
2831 in message and save_errno, and setting_up will always be true. Treat as
2832 a temporary error. */
2833
2834 #ifdef SUPPORT_TLS
2835 TLS_FAILED:
2836 code = '4';
2837 #endif
2838
2839 /* If the failure happened while setting up the call, see if the failure was
2840 a 5xx response (this will either be on connection, or following HELO - a 5xx
2841 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
2842 never going to accept them. For other errors during setting up (timeouts or
2843 whatever), defer all addresses, and yield DEFER, so that the host is not
2844 tried again for a while. */
2845
2846 FAILED:
2847 ok = FALSE; /* For when reached by GOTO */
2848 set_message = message;
2849
2850 if (setting_up)
2851 {
2852 if (code == '5')
2853 set_rc = FAIL;
2854 else
2855 yield = set_rc = DEFER;
2856 }
2857
2858 /* We want to handle timeouts after MAIL or "." and loss of connection after
2859 "." specially. They can indicate a problem with the sender address or with
2860 the contents of the message rather than a real error on the connection. These
2861 cases are treated in the same way as a 4xx response. This next bit of code
2862 does the classification. */
2863
2864 else
2865 {
2866 BOOL message_error;
2867
2868 switch(save_errno)
2869 {
2870 #ifdef SUPPORT_I18N
2871 case ERRNO_UTF8_FWD:
2872 code = '5';
2873 /*FALLTHROUGH*/
2874 #endif
2875 case 0:
2876 case ERRNO_MAIL4XX:
2877 case ERRNO_DATA4XX:
2878 message_error = TRUE;
2879 break;
2880
2881 case ETIMEDOUT:
2882 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
2883 Ustrncmp(smtp_command,"end ",4) == 0;
2884 break;
2885
2886 case ERRNO_SMTPCLOSED:
2887 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
2888 break;
2889
2890 default:
2891 message_error = FALSE;
2892 break;
2893 }
2894
2895 /* Handle the cases that are treated as message errors. These are:
2896
2897 (a) negative response or timeout after MAIL
2898 (b) negative response after DATA
2899 (c) negative response or timeout or dropped connection after "."
2900 (d) utf8 support required and not offered
2901
2902 It won't be a negative response or timeout after RCPT, as that is dealt
2903 with separately above. The action in all cases is to set an appropriate
2904 error code for all the addresses, but to leave yield set to OK because the
2905 host itself has not failed. Of course, it might in practice have failed
2906 when we've had a timeout, but if so, we'll discover that at the next
2907 delivery attempt. For a temporary error, set the message_defer flag, and
2908 write to the logs for information if this is not the last host. The error
2909 for the last host will be logged as part of the address's log line. */
2910
2911 if (message_error)
2912 {
2913 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
2914
2915 /* If there's an errno, the message contains just the identity of
2916 the host. */
2917
2918 if (code == '5')
2919 set_rc = FAIL;
2920 else /* Anything other than 5 is treated as temporary */
2921 {
2922 set_rc = DEFER;
2923 if (save_errno > 0)
2924 message = US string_sprintf("%s: %s", message, strerror(save_errno));
2925 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
2926 msglog_line(host, message);
2927 *message_defer = TRUE;
2928 }
2929 }
2930
2931 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
2932 ".", or some other transportation error. We defer all addresses and yield
2933 DEFER, except for the case of failed add_headers expansion, or a transport
2934 filter failure, when the yield should be ERROR, to stop it trying other
2935 hosts. */
2936
2937 else
2938 {
2939 set_rc = DEFER;
2940 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
2941 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
2942 }
2943 }
2944
2945 set_errno(addrlist, save_errno, set_message, set_rc, pass_message, host
2946 #ifdef EXPERIMENTAL_DSN_INFO
2947 , smtp_greeting, helo_response
2948 #endif
2949 );
2950 }
2951
2952
2953 /* If all has gone well, send_quit will be set TRUE, implying we can end the
2954 SMTP session tidily. However, if there were too many addresses to send in one
2955 message (indicated by first_addr being non-NULL) we want to carry on with the
2956 rest of them. Also, it is desirable to send more than one message down the SMTP
2957 connection if there are several waiting, provided we haven't already sent so
2958 many as to hit the configured limit. The function transport_check_waiting looks
2959 for a waiting message and returns its id. Then transport_pass_socket tries to
2960 set up a continued delivery by passing the socket on to another process. The
2961 variable send_rset is FALSE if a message has just been successfully transfered.
2962
2963 If we are already sending down a continued channel, there may be further
2964 addresses not yet delivered that are aimed at the same host, but which have not
2965 been passed in this run of the transport. In this case, continue_more will be
2966 true, and all we should do is send RSET if necessary, and return, leaving the
2967 channel open.
2968
2969 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
2970 do not want to continue with other messages down the same channel, because that
2971 can lead to looping between two or more messages, all with the same,
2972 temporarily failing address(es). [The retry information isn't updated yet, so
2973 new processes keep on trying.] We probably also don't want to try more of this
2974 message's addresses either.
2975
2976 If we have started a TLS session, we have to end it before passing the
2977 connection to a new process. However, not all servers can handle this (Exim
2978 can), so we do not pass such a connection on if the host matches
2979 hosts_nopass_tls. */
2980
2981 DEBUG(D_transport)
2982 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
2983 "yield=%d first_address is %sNULL\n", ok, send_quit, send_rset,
2984 continue_more, yield, (first_addr == NULL)? "":"not ");
2985
2986 if (completed_address && ok && send_quit)
2987 {
2988 BOOL more;
2989 smtp_compare_t t_compare;
2990
2991 t_compare.tblock = tblock;
2992 t_compare.current_sender_address = sender_address;
2993
2994 if ( first_addr != NULL
2995 || continue_more
2996 || ( ( tls_out.active < 0
2997 || verify_check_given_host(&ob->hosts_nopass_tls, host) != OK
2998 )
2999 &&
3000 transport_check_waiting(tblock->name, host->name,
3001 tblock->connection_max_messages, new_message_id, &more,
3002 (oicf)smtp_are_same_identities, (void*)&t_compare)
3003 ) )
3004 {
3005 uschar *msg;
3006 BOOL pass_message;
3007
3008 if (send_rset)
3009 {
3010 if (! (ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
3011 {
3012 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
3013 host->address, strerror(save_errno));
3014 send_quit = FALSE;
3015 }
3016 else if (! (ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
3017 ob->command_timeout)))
3018 {
3019 int code;
3020 send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
3021 &pass_message);
3022 if (!send_quit)
3023 {
3024 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
3025 host->name, host->address, msg);
3026 }
3027 }
3028 }
3029
3030 /* Either RSET was not needed, or it succeeded */
3031
3032 if (ok)
3033 {
3034 if (first_addr != NULL) /* More addresses still to be sent */
3035 { /* in this run of the transport */
3036 continue_sequence++; /* Causes * in logging */
3037 goto SEND_MESSAGE;
3038 }
3039 if (continue_more) return yield; /* More addresses for another run */
3040
3041 /* Pass the socket to a new Exim process. Before doing so, we must shut
3042 down TLS. Not all MTAs allow for the continuation of the SMTP session
3043 when TLS is shut down. We test for this by sending a new EHLO. If we
3044 don't get a good response, we don't attempt to pass the socket on. */
3045
3046 #ifdef SUPPORT_TLS
3047 if (tls_out.active >= 0)
3048 {
3049 tls_close(FALSE, TRUE);
3050 smtp_peer_options = smtp_peer_options_wrap;
3051 if (smtps)
3052 ok = FALSE;
3053 else
3054 ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
3055 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
3056 ob->command_timeout);
3057 }
3058 #endif
3059
3060 /* If the socket is successfully passed, we musn't send QUIT (or
3061 indeed anything!) from here. */
3062
3063 /*XXX DSN_INFO: assume likely to do new HELO; but for greet we'll want to
3064 propagate it from the initial
3065 */
3066 if (ok && transport_pass_socket(tblock->name, host->name, host->address,
3067 new_message_id, inblock.sock))
3068 send_quit = FALSE;
3069 }
3070
3071 /* If RSET failed and there are addresses left, they get deferred. */
3072
3073 else set_errno(first_addr, errno, msg, DEFER, FALSE, host
3074 #ifdef EXPERIMENTAL_DSN_INFO
3075 , smtp_greeting, helo_response
3076 #endif
3077 );
3078 }
3079 }
3080
3081 /* End off tidily with QUIT unless the connection has died or the socket has
3082 been passed to another process. There has been discussion on the net about what
3083 to do after sending QUIT. The wording of the RFC suggests that it is necessary
3084 to wait for a response, but on the other hand, there isn't anything one can do
3085 with an error response, other than log it. Exim used to do that. However,
3086 further discussion suggested that it is positively advantageous not to wait for
3087 the response, but to close the session immediately. This is supposed to move
3088 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
3089 load from the server. (Hosts that are both servers and clients may not see much
3090 difference, of course.) Further discussion indicated that this was safe to do
3091 on Unix systems which have decent implementations of TCP/IP that leave the
3092 connection around for a while (TIME_WAIT) after the application has gone away.
3093 This enables the response sent by the server to be properly ACKed rather than
3094 timed out, as can happen on broken TCP/IP implementations on other OS.
3095
3096 This change is being made on 31-Jul-98. After over a year of trouble-free
3097 operation, the old commented-out code was removed on 17-Sep-99. */
3098
3099 SEND_QUIT:
3100 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
3101
3102 END_OFF:
3103
3104 #ifdef SUPPORT_TLS
3105 tls_close(FALSE, TRUE);
3106 #endif
3107
3108 /* Close the socket, and return the appropriate value, first setting
3109 works because the NULL setting is passed back to the calling process, and
3110 remote_max_parallel is forced to 1 when delivering over an existing connection,
3111
3112 If all went well and continue_more is set, we shouldn't actually get here if
3113 there are further addresses, as the return above will be taken. However,
3114 writing RSET might have failed, or there may be other addresses whose hosts are
3115 specified in the transports, and therefore not visible at top level, in which
3116 case continue_more won't get set. */
3117
3118 HDEBUG(D_transport|D_acl|D_v) debug_printf(" SMTP(close)>>\n");
3119 (void)close(inblock.sock);
3120
3121 #ifndef DISABLE_EVENT
3122 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
3123 #endif
3124
3125 continue_transport = NULL;
3126 continue_hostname = NULL;
3127 return yield;
3128 }
3129
3130
3131
3132
3133 /*************************************************
3134 * Closedown entry point *
3135 *************************************************/
3136
3137 /* This function is called when exim is passed an open smtp channel
3138 from another incarnation, but the message which it has been asked
3139 to deliver no longer exists. The channel is on stdin.
3140
3141 We might do fancy things like looking for another message to send down
3142 the channel, but if the one we sought has gone, it has probably been
3143 delivered by some other process that itself will seek further messages,
3144 so just close down our connection.
3145
3146 Argument: pointer to the transport instance block
3147 Returns: nothing
3148 */
3149
3150 void
3151 smtp_transport_closedown(transport_instance *tblock)
3152 {
3153 smtp_transport_options_block *ob =
3154 (smtp_transport_options_block *)(tblock->options_block);
3155 smtp_inblock inblock;
3156 smtp_outblock outblock;
3157 uschar buffer[256];
3158 uschar inbuffer[4096];
3159 uschar outbuffer[16];
3160
3161 inblock.sock = fileno(stdin);
3162 inblock.buffer = inbuffer;
3163 inblock.buffersize = sizeof(inbuffer);
3164 inblock.ptr = inbuffer;
3165 inblock.ptrend = inbuffer;
3166
3167 outblock.sock = inblock.sock;
3168 outblock.buffersize = sizeof(outbuffer);
3169 outblock.buffer = outbuffer;
3170 outblock.ptr = outbuffer;
3171 outblock.cmd_count = 0;
3172 outblock.authenticating = FALSE;
3173
3174 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
3175 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
3176 ob->command_timeout);
3177 (void)close(inblock.sock);
3178 }
3179
3180
3181
3182 /*************************************************
3183 * Prepare addresses for delivery *
3184 *************************************************/
3185
3186 /* This function is called to flush out error settings from previous delivery
3187 attempts to other hosts. It also records whether we got here via an MX record
3188 or not in the more_errno field of the address. We are interested only in
3189 addresses that are still marked DEFER - others may have got delivered to a
3190 previously considered IP address. Set their status to PENDING_DEFER to indicate
3191 which ones are relevant this time.
3192
3193 Arguments:
3194 addrlist the list of addresses
3195 host the host we are delivering to
3196
3197 Returns: the first address for this delivery
3198 */
3199
3200 static address_item *
3201 prepare_addresses(address_item *addrlist, host_item *host)
3202 {
3203 address_item *first_addr = NULL;
3204 address_item *addr;
3205 for (addr = addrlist; addr; addr = addr->next)
3206 if (addr->transport_return == DEFER)
3207 {
3208 if (!first_addr) first_addr = addr;
3209 addr->transport_return = PENDING_DEFER;
3210 addr->basic_errno = 0;
3211 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
3212 addr->message = NULL;
3213 #ifdef SUPPORT_TLS
3214 addr->cipher = NULL;
3215 addr->ourcert = NULL;
3216 addr->peercert = NULL;
3217 addr->peerdn = NULL;
3218 addr->ocsp = OCSP_NOT_REQ;
3219 #endif
3220 #ifdef EXPERIMENTAL_DSN_INFO
3221 addr->smtp_greeting = NULL;
3222 addr->helo_response = NULL;
3223 #endif
3224 }
3225 return first_addr;
3226 }
3227
3228
3229
3230 /*************************************************
3231 * Main entry point *
3232 *************************************************/
3233
3234 /* See local README for interface details. As this is a remote transport, it is
3235 given a chain of addresses to be delivered in one connection, if possible. It
3236 always returns TRUE, indicating that each address has its own independent
3237 status set, except if there is a setting up problem, in which case it returns
3238 FALSE. */
3239
3240 BOOL
3241 smtp_transport_entry(
3242 transport_instance *tblock, /* data for this instantiation */
3243 address_item *addrlist) /* addresses we are working on */
3244 {
3245 int cutoff_retry;
3246 int port;
3247 int hosts_defer = 0;
3248 int hosts_fail = 0;
3249 int hosts_looked_up = 0;
3250 int hosts_retry = 0;
3251 int hosts_serial = 0;
3252 int hosts_total = 0;
3253 int total_hosts_tried = 0;
3254 address_item *addr;
3255 BOOL expired = TRUE;
3256 uschar *expanded_hosts = NULL;
3257 uschar *pistring;
3258 uschar *tid = string_sprintf("%s transport", tblock->name);
3259 smtp_transport_options_block *ob =
3260 (smtp_transport_options_block *)(tblock->options_block);
3261 host_item *hostlist = addrlist->host_list;
3262 host_item *host = NULL;
3263
3264 DEBUG(D_transport)
3265 {
3266 debug_printf("%s transport entered\n", tblock->name);
3267 for (addr = addrlist; addr; addr = addr->next)
3268 debug_printf(" %s\n", addr->address);
3269 if (hostlist)
3270 {
3271 debug_printf("hostlist:\n");
3272 for (host = hostlist; host; host = host->next)
3273 debug_printf(" %s:%d\n", host->name, host->port);
3274 }
3275 if (continue_hostname) debug_printf("already connected to %s [%s]\n",
3276 continue_hostname, continue_host_address);
3277 }
3278
3279 /* Set the flag requesting that these hosts be added to the waiting
3280 database if the delivery fails temporarily or if we are running with
3281 queue_smtp or a 2-stage queue run. This gets unset for certain
3282 kinds of error, typically those that are specific to the message. */
3283
3284 update_waiting = TRUE;
3285
3286 /* If a host list is not defined for the addresses - they must all have the
3287 same one in order to be passed to a single transport - or if the transport has
3288 a host list with hosts_override set, use the host list supplied with the
3289 transport. It is an error for this not to exist. */
3290
3291 if (!hostlist || (ob->hosts_override && ob->hosts))
3292 {
3293 if (!ob->hosts)
3294 {
3295 addrlist->message = string_sprintf("%s transport called with no hosts set",
3296 tblock->name);
3297 addrlist->transport_return = PANIC;
3298 return FALSE; /* Only top address has status */
3299 }
3300
3301 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
3302 ob->hosts);
3303
3304 /* If the transport's host list contains no '$' characters, and we are not
3305 randomizing, it is fixed and therefore a chain of hosts can be built once
3306 and for all, and remembered for subsequent use by other calls to this
3307 transport. If, on the other hand, the host list does contain '$', or we are
3308 randomizing its order, we have to rebuild it each time. In the fixed case,
3309 as the hosts string will never be used again, it doesn't matter that we
3310 replace all the : characters with zeros. */
3311
3312 if (!ob->hostlist)
3313 {
3314 uschar *s = ob->hosts;
3315
3316 if (Ustrchr(s, '$') != NULL)
3317 {
3318 if (!(expanded_hosts = expand_string(s)))
3319 {
3320 addrlist->message = string_sprintf("failed to expand list of hosts "
3321 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
3322 addrlist->transport_return = search_find_defer ? DEFER : PANIC;
3323 return FALSE; /* Only top address has status */
3324 }
3325 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
3326 "\"%s\"\n", s, expanded_hosts);
3327 s = expanded_hosts;
3328 }
3329 else
3330 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
3331
3332 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
3333
3334 /* Check that the expansion yielded something useful. */
3335 if (!hostlist)
3336 {
3337 addrlist->message =
3338 string_sprintf("%s transport has empty hosts setting", tblock->name);
3339 addrlist->transport_return = PANIC;
3340 return FALSE; /* Only top address has status */
3341 }
3342
3343 /* If there was no expansion of hosts, save the host list for
3344 next time. */
3345
3346 if (!expanded_hosts) ob->hostlist = hostlist;
3347 }
3348
3349 /* This is not the first time this transport has been run in this delivery;
3350 the host list was built previously. */
3351
3352 else
3353 hostlist = ob->hostlist;
3354 }
3355
3356 /* The host list was supplied with the address. If hosts_randomize is set, we
3357 must sort it into a random order if it did not come from MX records and has not
3358 already been randomized (but don't bother if continuing down an existing
3359 connection). */
3360
3361 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continue_hostname)
3362 {
3363 host_item *newlist = NULL;
3364 while (hostlist)
3365 {
3366 host_item *h = hostlist;
3367 hostlist = hostlist->next;
3368
3369 h->sort_key = random_number(100);
3370
3371 if (!newlist)
3372 {
3373 h->next = NULL;
3374 newlist = h;
3375 }
3376 else if (h->sort_key < newlist->sort_key)
3377 {
3378 h->next = newlist;
3379 newlist = h;
3380 }
3381 else
3382 {
3383 host_item *hh = newlist;
3384 while (hh->next)
3385 {
3386 if (h->sort_key < hh->next->sort_key) break;
3387 hh = hh->next;
3388 }
3389 h->next = hh->next;
3390 hh->next = h;
3391 }
3392 }
3393
3394 hostlist = addrlist->host_list = newlist;
3395 }
3396
3397 /* Sort out the default port. */
3398
3399 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
3400
3401 /* For each host-plus-IP-address on the list:
3402
3403 . If this is a continued delivery and the host isn't the one with the
3404 current connection, skip.
3405
3406 . If the status is unusable (i.e. previously failed or retry checked), skip.
3407
3408 . If no IP address set, get the address, either by turning the name into
3409 an address, calling gethostbyname if gethostbyname is on, or by calling
3410 the DNS. The DNS may yield multiple addresses, in which case insert the
3411 extra ones into the list.
3412
3413 . Get the retry data if not previously obtained for this address and set the
3414 field which remembers the state of this address. Skip if the retry time is
3415 not reached. If not, remember whether retry data was found. The retry string
3416 contains both the name and the IP address.
3417
3418 . Scan the list of addresses and mark those whose status is DEFER as
3419 PENDING_DEFER. These are the only ones that will be processed in this cycle
3420 of the hosts loop.
3421
3422 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
3423 Some addresses may be successfully delivered, others may fail, and yet
3424 others may get temporary errors and so get marked DEFER.
3425
3426 . The return from the delivery attempt is OK if a connection was made and a
3427 valid SMTP dialogue was completed. Otherwise it is DEFER.
3428
3429 . If OK, add a "remove" retry item for this host/IPaddress, if any.
3430
3431 . If fail to connect, or other defer state, add a retry item.
3432
3433 . If there are any addresses whose status is still DEFER, carry on to the
3434 next host/IPaddress, unless we have tried the number of hosts given
3435 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
3436 there is some fancy logic for hosts_max_try that means its limit can be
3437 overstepped in some circumstances.
3438
3439 If we get to the end of the list, all hosts have deferred at least one address,
3440 or not reached their retry times. If delay_after_cutoff is unset, it requests a
3441 delivery attempt to those hosts whose last try was before the arrival time of
3442 the current message. To cope with this, we have to go round the loop a second
3443 time. After that, set the status and error data for any addresses that haven't
3444 had it set already. */
3445
3446 for (cutoff_retry = 0;
3447 expired && cutoff_retry < (ob->delay_after_cutoff ? 1 : 2);
3448 cutoff_retry++)
3449 {
3450 host_item *nexthost = NULL;
3451 int unexpired_hosts_tried = 0;
3452
3453 for (host = hostlist;
3454 host
3455 && unexpired_hosts_tried < ob->hosts_max_try
3456 && total_hosts_tried < ob->hosts_max_try_hardlimit;
3457 host = nexthost)
3458 {
3459 int rc;
3460 int host_af;
3461 uschar *rs;
3462 BOOL host_is_expired = FALSE;
3463 BOOL message_defer = FALSE;
3464 BOOL some_deferred = FALSE;
3465 address_item *first_addr = NULL;
3466 uschar *interface = NULL;
3467 uschar *retry_host_key = NULL;
3468 uschar *retry_message_key = NULL;
3469 uschar *serialize_key = NULL;
3470
3471 /* Default next host is next host. :-) But this can vary if the
3472 hosts_max_try limit is hit (see below). It may also be reset if a host
3473 address is looked up here (in case the host was multihomed). */
3474
3475 nexthost = host->next;
3476
3477 /* If the address hasn't yet been obtained from the host name, look it up
3478 now, unless the host is already marked as unusable. If it is marked as
3479 unusable, it means that the router was unable to find its IP address (in
3480 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
3481 the lookup failed last time. We don't get this far if *all* MX records
3482 point to non-existent hosts; that is treated as a hard error.
3483
3484 We can just skip this host entirely. When the hosts came from the router,
3485 the address will timeout based on the other host(s); when the address is
3486 looked up below, there is an explicit retry record added.
3487
3488 Note that we mustn't skip unusable hosts if the address is not unset; they
3489 may be needed as expired hosts on the 2nd time round the cutoff loop. */
3490
3491 if (!host->address)
3492 {
3493 int new_port, flags;
3494 host_item *hh;
3495
3496 if (host->status >= hstatus_unusable)
3497 {
3498 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
3499 host->name);
3500 continue;
3501 }
3502
3503 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
3504
3505 /* The host name is permitted to have an attached port. Find it, and
3506 strip it from the name. Just remember it for now. */
3507
3508 new_port = host_item_get_port(host);
3509
3510 /* Count hosts looked up */
3511
3512 hosts_looked_up++;
3513
3514 /* Find by name if so configured, or if it's an IP address. We don't
3515 just copy the IP address, because we need the test-for-local to happen. */
3516
3517 flags = HOST_FIND_BY_A;
3518 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
3519 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
3520
3521 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
3522 rc = host_find_byname(host, NULL, flags, NULL, TRUE);
3523 else
3524 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
3525 &ob->dnssec, /* domains for request/require */
3526 NULL, NULL);
3527
3528 /* Update the host (and any additional blocks, resulting from
3529 multihoming) with a host-specific port, if any. */
3530
3531 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
3532
3533 /* Failure to find the host at this time (usually DNS temporary failure)
3534 is really a kind of routing failure rather than a transport failure.
3535 Therefore we add a retry item of the routing kind, not to stop us trying
3536 to look this name up here again, but to ensure the address gets timed
3537 out if the failures go on long enough. A complete failure at this point
3538 commonly points to a configuration error, but the best action is still
3539 to carry on for the next host. */
3540
3541 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
3542 {
3543 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
3544 expired = FALSE;
3545 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
3546 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
3547 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
3548 host->status = hstatus_unusable;
3549
3550 for (addr = addrlist; addr; addr = addr->next)
3551 {
3552 if (addr->transport_return != DEFER) continue;
3553 addr->basic_errno = ERRNO_UNKNOWNHOST;
3554 addr->message =
3555 string_sprintf("failed to lookup IP address for %s", host->name);
3556 }
3557 continue;
3558 }
3559
3560 /* If the host is actually the local host, we may have a problem, or
3561 there may be some cunning configuration going on. In the problem case,
3562 log things and give up. The default transport status is already DEFER. */
3563
3564 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
3565 {
3566 for (addr = addrlist; addr; addr = addr->next)
3567 {
3568 addr->basic_errno = 0;
3569 addr->message = string_sprintf("%s transport found host %s to be "
3570 "local", tblock->name, host->name);
3571 }
3572 goto END_TRANSPORT;
3573 }
3574 } /* End of block for IP address lookup */
3575
3576 /* If this is a continued delivery, we are interested only in the host
3577 which matches the name of the existing open channel. The check is put
3578 here after the local host lookup, in case the name gets expanded as a
3579 result of the lookup. Set expired FALSE, to save the outer loop executing
3580 twice. */
3581
3582 if ( continue_hostname
3583 && ( Ustrcmp(continue_hostname, host->name) != 0
3584 || Ustrcmp(continue_host_address, host->address) != 0
3585 ) )
3586 {
3587 expired = FALSE;
3588 continue; /* With next host */
3589 }
3590
3591 /* Reset the default next host in case a multihomed host whose addresses
3592 are not looked up till just above added to the host list. */
3593
3594 nexthost = host->next;
3595
3596 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
3597 domain is in queue_smtp_domains, we don't actually want to attempt any
3598 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
3599 there is a lookup defer in queue_smtp_domains, proceed as if the domain
3600 were not in it. We don't want to hold up all SMTP deliveries! Except when
3601 doing a two-stage queue run, don't do this if forcing. */
3602
3603 if ((!deliver_force || queue_2stage) && (queue_smtp ||
3604 match_isinlist(addrlist->domain,
3605 (const uschar **)&queue_smtp_domains, 0,
3606 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
3607 {
3608 expired = FALSE;
3609 for (addr = addrlist; addr; addr = addr->next)
3610 if (addr->transport_return == DEFER)
3611 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
3612 continue; /* With next host */
3613 }
3614
3615 /* Count hosts being considered - purely for an intelligent comment
3616 if none are usable. */
3617
3618 hosts_total++;
3619
3620 /* Set $host and $host address now in case they are needed for the
3621 interface expansion or the serialize_hosts check; they remain set if an
3622 actual delivery happens. */
3623
3624 deliver_host = host->name;
3625 deliver_host_address = host->address;
3626 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
3627 : host->dnssec == DS_NO ? US"no"
3628 : US"";
3629
3630 /* Set up a string for adding to the retry key if the port number is not
3631 the standard SMTP port. A host may have its own port setting that overrides
3632 the default. */
3633
3634 pistring = string_sprintf(":%d", host->port == PORT_NONE
3635 ? port : host->port);
3636 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
3637
3638 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
3639 string is set, even if constant (as different transports can have different
3640 constant settings), we must add it to the key that is used for retries,
3641 because connections to the same host from a different interface should be
3642 treated separately. */
3643
3644 host_af = Ustrchr(host->address, ':') == NULL ? AF_INET : AF_INET6;
3645 if ((rs = ob->interface) && *rs)
3646 {
3647 if (!smtp_get_interface(rs, host_af, addrlist, &interface, tid))
3648 return FALSE;
3649 pistring = string_sprintf("%s/%s", pistring, interface);
3650 }
3651
3652 /* The first time round the outer loop, check the status of the host by
3653 inspecting the retry data. The second time round, we are interested only
3654 in expired hosts that haven't been tried since this message arrived. */
3655
3656 if (cutoff_retry == 0)
3657 {
3658 BOOL incl_ip;
3659 /* Ensure the status of the address is set by checking retry data if
3660 necessary. There may be host-specific retry data (applicable to all
3661 messages) and also data for retries of a specific message at this host.
3662 If either of these retry records are actually read, the keys used are
3663 returned to save recomputing them later. */
3664
3665 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3666 US"retry_include_ip_address", ob->retry_include_ip_address,
3667 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3668 continue; /* with next host */
3669
3670 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
3671 incl_ip, &retry_host_key, &retry_message_key);
3672
3673 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
3674 (host->address == NULL)? US"" : host->address, pistring,
3675 (host->status == hstatus_usable)? "usable" :
3676 (host->status == hstatus_unusable)? "unusable" :
3677 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
3678
3679 /* Skip this address if not usable at this time, noting if it wasn't
3680 actually expired, both locally and in the address. */
3681
3682 switch (host->status)
3683 {
3684 case hstatus_unusable:
3685 expired = FALSE;
3686 setflag(addrlist, af_retry_skipped);
3687 /* Fall through */
3688
3689 case hstatus_unusable_expired:
3690 switch (host->why)
3691 {
3692 case hwhy_retry: hosts_retry++; break;
3693 case hwhy_failed: hosts_fail++; break;
3694 case hwhy_deferred: hosts_defer++; break;
3695 }
3696
3697 /* If there was a retry message key, implying that previously there
3698 was a message-specific defer, we don't want to update the list of
3699 messages waiting for these hosts. */
3700
3701 if (retry_message_key) update_waiting = FALSE;
3702 continue; /* With the next host or IP address */
3703 }
3704 }
3705
3706 /* Second time round the loop: if the address is set but expired, and
3707 the message is newer than the last try, let it through. */
3708
3709 else
3710 {
3711 if ( !host->address
3712 || host->status != hstatus_unusable_expired
3713 || host->last_try > received_time)
3714 continue;
3715 DEBUG(D_transport) debug_printf("trying expired host %s [%s]%s\n",
3716 host->name, host->address, pistring);
3717 host_is_expired = TRUE;
3718 }
3719
3720 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
3721 it remains TRUE only if all hosts are expired and none are actually tried.
3722 */
3723
3724 expired = FALSE;
3725
3726 /* If this host is listed as one to which access must be serialized,
3727 see if another Exim process has a connection to it, and if so, skip
3728 this host. If not, update the database to record our connection to it
3729 and remember this for later deletion. Do not do any of this if we are
3730 sending the message down a pre-existing connection. */
3731
3732 if ( !continue_hostname
3733 && verify_check_given_host(&ob->serialize_hosts, host) == OK)
3734 {
3735 serialize_key = string_sprintf("host-serialize-%s", host->name);
3736 if (!enq_start(serialize_key, 1))
3737 {
3738 DEBUG(D_transport)
3739 debug_printf("skipping host %s because another Exim process "
3740 "is connected to it\n", host->name);
3741 hosts_serial++;
3742 continue;
3743 }
3744 }
3745
3746 /* OK, we have an IP address that is not waiting for its retry time to
3747 arrive (it might be expired) OR (second time round the loop) we have an
3748 expired host that hasn't been tried since the message arrived. Have a go
3749 at delivering the message to it. First prepare the addresses by flushing
3750 out the result of previous attempts, and finding the first address that
3751 is still to be delivered. */
3752
3753 first_addr = prepare_addresses(addrlist, host);
3754
3755 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
3756 message_id, host->name, host->address, addrlist->address,
3757 addrlist->next ? ", ..." : "");
3758
3759 set_process_info("delivering %s to %s [%s] (%s%s)",
3760 message_id, host->name, host->address, addrlist->address,
3761 addrlist->next ? ", ..." : "");
3762
3763 /* This is not for real; don't do the delivery. If there are
3764 any remaining hosts, list them. */
3765
3766 if (dont_deliver)
3767 {
3768 host_item *host2;
3769 set_errno_nohost(addrlist, 0, NULL, OK, FALSE);
3770 for (addr = addrlist; addr; addr = addr->next)
3771 {
3772 addr->host_used = host;
3773 addr->special_action = '*';
3774 addr->message = US"delivery bypassed by -N option";
3775 }
3776 DEBUG(D_transport)
3777 {
3778 debug_printf("*** delivery by %s transport bypassed by -N option\n"
3779 "*** host and remaining hosts:\n", tblock->name);
3780 for (host2 = host; host2; host2 = host2->next)
3781 debug_printf(" %s [%s]\n", host2->name,
3782 host2->address ? host2->address : US"unset");
3783 }
3784 rc = OK;
3785 }
3786
3787 /* This is for real. If the host is expired, we don't count it for
3788 hosts_max_retry. This ensures that all hosts must expire before an address
3789 is timed out, unless hosts_max_try_hardlimit (which protects against
3790 lunatic DNS configurations) is reached.
3791
3792 If the host is not expired and we are about to hit the hosts_max_retry
3793 limit, check to see if there is a subsequent hosts with a different MX
3794 value. If so, make that the next host, and don't count this one. This is a
3795 heuristic to make sure that different MXs do get tried. With a normal kind
3796 of retry rule, they would get tried anyway when the earlier hosts were
3797 delayed, but if the domain has a "retry every time" type of rule - as is
3798 often used for the the very large ISPs, that won't happen. */
3799
3800 else
3801 {
3802 host_item * thost;
3803 /* Make a copy of the host if it is local to this invocation
3804 of the transport. */
3805
3806 if (expanded_hosts)
3807 {
3808 thost = store_get(sizeof(host_item));
3809 *thost = *host;
3810 thost->name = string_copy(host->name);
3811 thost->address = string_copy(host->address);
3812 }
3813 else
3814 thost = host;
3815
3816 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
3817 {
3818 host_item *h;
3819 DEBUG(D_transport)
3820 debug_printf("hosts_max_try limit reached with this host\n");
3821 for (h = host; h; h = h->next) if (h->mx != host->mx)
3822 {
3823 nexthost = h;
3824 unexpired_hosts_tried--;
3825 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
3826 "and will be tried\n");
3827 break;
3828 }
3829 }
3830
3831 /* Attempt the delivery. */
3832
3833 total_hosts_tried++;
3834 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
3835 &message_defer, FALSE);
3836
3837 /* Yield is one of:
3838 OK => connection made, each address contains its result;
3839 message_defer is set for message-specific defers (when all
3840 recipients are marked defer)
3841 DEFER => there was a non-message-specific delivery problem;
3842 ERROR => there was a problem setting up the arguments for a filter,
3843 or there was a problem with expanding added headers
3844 */
3845
3846 /* If the result is not OK, there was a non-message-specific problem.
3847 If the result is DEFER, we need to write to the logs saying what happened
3848 for this particular host, except in the case of authentication and TLS
3849 failures, where the log has already been written. If all hosts defer a
3850 general message is written at the end. */
3851
3852 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL
3853 && first_addr->basic_errno != ERRNO_TLSFAILURE)
3854 write_logs(first_addr, host);
3855
3856 #ifndef DISABLE_EVENT
3857 if (rc == DEFER)
3858 deferred_event_raise(first_addr, host);
3859 #endif
3860
3861 /* If STARTTLS was accepted, but there was a failure in setting up the
3862 TLS session (usually a certificate screwup), and the host is not in
3863 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
3864 TLS forcibly turned off. We have to start from scratch with a new SMTP
3865 connection. That's why the retry is done from here, not from within
3866 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
3867 session, so the in-clear transmission after those errors, if permitted,
3868 happens inside smtp_deliver().] */
3869
3870 #ifdef SUPPORT_TLS
3871 if ( rc == DEFER
3872 && first_addr->basic_errno == ERRNO_TLSFAILURE
3873 && ob->tls_tempfail_tryclear
3874 && verify_check_given_host(&ob->hosts_require_tls, host) != OK
3875 )
3876 {
3877 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
3878 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
3879 first_addr = prepare_addresses(addrlist, host);
3880 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
3881 &message_defer, TRUE);
3882 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
3883 write_logs(first_addr, host);
3884 # ifndef DISABLE_EVENT
3885 if (rc