c6443978630ffb4f8e1bcdc018de8d17e92f402e
[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 static int off = 0; /* for use by setsockopt */
290
291
292 /*************************************************
293 * Setup entry point *
294 *************************************************/
295
296 /* This function is called when the transport is about to be used,
297 but before running it in a sub-process. It is used for two things:
298
299 (1) To set the fallback host list in addresses, when delivering.
300 (2) To pass back the interface, port, protocol, and other options, for use
301 during callout verification.
302
303 Arguments:
304 tblock pointer to the transport instance block
305 addrlist list of addresses about to be transported
306 tf if not NULL, pointer to block in which to return options
307 uid the uid that will be set (not used)
308 gid the gid that will be set (not used)
309 errmsg place for error message (not used)
310
311 Returns: OK always (FAIL, DEFER not used)
312 */
313
314 static int
315 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
316 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
317 {
318 smtp_transport_options_block *ob =
319 (smtp_transport_options_block *)(tblock->options_block);
320
321 errmsg = errmsg; /* Keep picky compilers happy */
322 uid = uid;
323 gid = gid;
324
325 /* Pass back options if required. This interface is getting very messy. */
326
327 if (tf != NULL)
328 {
329 tf->interface = ob->interface;
330 tf->port = ob->port;
331 tf->protocol = ob->protocol;
332 tf->hosts = ob->hosts;
333 tf->hosts_override = ob->hosts_override;
334 tf->hosts_randomize = ob->hosts_randomize;
335 tf->gethostbyname = ob->gethostbyname;
336 tf->qualify_single = ob->dns_qualify_single;
337 tf->search_parents = ob->dns_search_parents;
338 tf->helo_data = ob->helo_data;
339 }
340
341 /* Set the fallback host list for all the addresses that don't have fallback
342 host lists, provided that the local host wasn't present in the original host
343 list. */
344
345 if (!testflag(addrlist, af_local_host_removed))
346 {
347 for (; addrlist != NULL; addrlist = addrlist->next)
348 if (addrlist->fallback_hosts == NULL)
349 addrlist->fallback_hosts = ob->fallback_hostlist;
350 }
351
352 return OK;
353 }
354
355
356
357 /*************************************************
358 * Initialization entry point *
359 *************************************************/
360
361 /* Called for each instance, after its options have been read, to
362 enable consistency checks to be done, or anything else that needs
363 to be set up.
364
365 Argument: pointer to the transport instance block
366 Returns: nothing
367 */
368
369 void
370 smtp_transport_init(transport_instance *tblock)
371 {
372 smtp_transport_options_block *ob =
373 (smtp_transport_options_block *)(tblock->options_block);
374
375 /* Retry_use_local_part defaults FALSE if unset */
376
377 if (tblock->retry_use_local_part == TRUE_UNSET)
378 tblock->retry_use_local_part = FALSE;
379
380 /* Set the default port according to the protocol */
381
382 if (ob->port == NULL)
383 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
384 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
385
386 /* Set up the setup entry point, to be called before subprocesses for this
387 transport. */
388
389 tblock->setup = smtp_transport_setup;
390
391 /* Complain if any of the timeouts are zero. */
392
393 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
394 ob->final_timeout <= 0)
395 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
396 "command, data, or final timeout value is zero for %s transport",
397 tblock->name);
398
399 /* If hosts_override is set and there are local hosts, set the global
400 flag that stops verify from showing router hosts. */
401
402 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
403
404 /* If there are any fallback hosts listed, build a chain of host items
405 for them, but do not do any lookups at this time. */
406
407 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
408 }
409
410
411
412
413
414 /*************************************************
415 * Set delivery info into all active addresses *
416 *************************************************/
417
418 /* Only addresses whose status is >= PENDING are relevant. A lesser
419 status means that an address is not currently being processed.
420
421 Arguments:
422 addrlist points to a chain of addresses
423 errno_value to put in each address's errno field
424 msg to put in each address's message field
425 rc to put in each address's transport_return field
426 pass_message if TRUE, set the "pass message" flag in the address
427 host if set, mark addrs as having used this host
428 smtp_greeting from peer
429 helo_response from peer
430
431 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
432 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
433 this particular type of timeout.
434
435 Returns: nothing
436 */
437
438 static void
439 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
440 BOOL pass_message, host_item * host
441 #ifdef EXPERIMENTAL_DSN_INFO
442 , const uschar * smtp_greeting, const uschar * helo_response
443 #endif
444 )
445 {
446 address_item *addr;
447 int orvalue = 0;
448 if (errno_value == ERRNO_CONNECTTIMEOUT)
449 {
450 errno_value = ETIMEDOUT;
451 orvalue = RTEF_CTOUT;
452 }
453 for (addr = addrlist; addr; addr = addr->next)
454 if (addr->transport_return >= PENDING)
455 {
456 addr->basic_errno = errno_value;
457 addr->more_errno |= orvalue;
458 if (msg != NULL)
459 {
460 addr->message = msg;
461 if (pass_message) setflag(addr, af_pass_message);
462 }
463 addr->transport_return = rc;
464 if (host)
465 {
466 addr->host_used = host;
467 #ifdef EXPERIMENTAL_DSN_INFO
468 if (smtp_greeting)
469 {uschar * s = Ustrchr(smtp_greeting, '\n'); if (s) *s = '\0';}
470 addr->smtp_greeting = smtp_greeting;
471
472 if (helo_response)
473 {uschar * s = Ustrchr(helo_response, '\n'); if (s) *s = '\0';}
474 addr->helo_response = helo_response;
475 #endif
476 }
477 }
478 }
479
480 static void
481 set_errno_nohost(address_item *addrlist, int errno_value, uschar *msg, int rc,
482 BOOL pass_message)
483 {
484 set_errno(addrlist, errno_value, msg, rc, pass_message, NULL
485 #ifdef EXPERIMENTAL_DSN_INFO
486 , NULL, NULL
487 #endif
488 );
489 }
490
491
492 /*************************************************
493 * Check an SMTP response *
494 *************************************************/
495
496 /* This function is given an errno code and the SMTP response buffer
497 to analyse, together with the host identification for generating messages. It
498 sets an appropriate message and puts the first digit of the response code into
499 the yield variable. If no response was actually read, a suitable digit is
500 chosen.
501
502 Arguments:
503 host the current host, to get its name for messages
504 errno_value pointer to the errno value
505 more_errno from the top address for use with ERRNO_FILTER_FAIL
506 buffer the SMTP response buffer
507 yield where to put a one-digit SMTP response code
508 message where to put an errror message
509 pass_message set TRUE if message is an SMTP response
510
511 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
512 */
513
514 static BOOL
515 check_response(host_item *host, int *errno_value, int more_errno,
516 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
517 {
518 uschar * pl = pipelining_active ? US"pipelined " : US"";
519
520 *yield = '4'; /* Default setting is to give a temporary error */
521
522 /* Handle response timeout */
523
524 if (*errno_value == ETIMEDOUT)
525 {
526 *message = US string_sprintf("SMTP timeout after %s%s",
527 pl, smtp_command);
528 if (transport_count > 0)
529 *message = US string_sprintf("%s (%d bytes written)", *message,
530 transport_count);
531 return FALSE;
532 }
533
534 /* Handle malformed SMTP response */
535
536 if (*errno_value == ERRNO_SMTPFORMAT)
537 {
538 const uschar *malfresp = string_printing(buffer);
539 while (isspace(*malfresp)) malfresp++;
540 *message = *malfresp == 0
541 ? string_sprintf("Malformed SMTP reply (an empty line) "
542 "in response to %s%s", pl, smtp_command)
543 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
544 pl, smtp_command, malfresp);
545 return FALSE;
546 }
547
548 /* Handle a failed filter process error; can't send QUIT as we mustn't
549 end the DATA. */
550
551 if (*errno_value == ERRNO_FILTER_FAIL)
552 {
553 *message = US string_sprintf("transport filter process failed (%d)%s",
554 more_errno,
555 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
556 return FALSE;
557 }
558
559 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
560 end the DATA. */
561
562 if (*errno_value == ERRNO_CHHEADER_FAIL)
563 {
564 *message =
565 US string_sprintf("failed to expand headers_add or headers_remove: %s",
566 expand_string_message);
567 return FALSE;
568 }
569
570 /* Handle failure to write a complete data block */
571
572 if (*errno_value == ERRNO_WRITEINCOMPLETE)
573 {
574 *message = US string_sprintf("failed to write a data block");
575 return FALSE;
576 }
577
578 #ifdef SUPPORT_I18N
579 /* Handle lack of advertised SMTPUTF8, for international message */
580 if (*errno_value == ERRNO_UTF8_FWD)
581 {
582 *message = US string_sprintf("utf8 support required but not offered for forwarding");
583 DEBUG(D_deliver|D_transport) debug_printf("%s\n", *message);
584 return TRUE;
585 }
586 #endif
587
588 /* Handle error responses from the remote mailer. */
589
590 if (buffer[0] != 0)
591 {
592 const uschar *s = string_printing(buffer);
593 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
594 "%s", pl, smtp_command, s);
595 *pass_message = TRUE;
596 *yield = buffer[0];
597 return TRUE;
598 }
599
600 /* No data was read. If there is no errno, this must be the EOF (i.e.
601 connection closed) case, which causes deferral. An explicit connection reset
602 error has the same effect. Otherwise, put the host's identity in the message,
603 leaving the errno value to be interpreted as well. In all cases, we have to
604 assume the connection is now dead. */
605
606 if (*errno_value == 0 || *errno_value == ECONNRESET)
607 {
608 *errno_value = ERRNO_SMTPCLOSED;
609 *message = US string_sprintf("Remote host closed connection "
610 "in response to %s%s", pl, smtp_command);
611 }
612 else *message = US string_sprintf("%s [%s]", host->name, host->address);
613
614 return FALSE;
615 }
616
617
618
619 /*************************************************
620 * Write error message to logs *
621 *************************************************/
622
623 /* This writes to the main log and to the message log.
624
625 Arguments:
626 addr the address item containing error information
627 host the current host
628
629 Returns: nothing
630 */
631
632 static void
633 write_logs(address_item *addr, host_item *host)
634 {
635 uschar * message = LOGGING(outgoing_port)
636 ? string_sprintf("H=%s [%s]:%d", host->name, host->address,
637 host->port == PORT_NONE ? 25 : host->port)
638 : string_sprintf("H=%s [%s]", host->name, host->address);
639
640 if (addr->message)
641 {
642 message = string_sprintf("%s: %s", message, addr->message);
643 if (addr->basic_errno > 0)
644 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
645 log_write(0, LOG_MAIN, "%s", message);
646 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
647 }
648 else
649 {
650 const uschar * s = exim_errstr(addr->basic_errno);
651 log_write(0, LOG_MAIN, "%s %s", message, s);
652 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), message, s);
653 }
654 }
655
656 static void
657 msglog_line(host_item * host, uschar * message)
658 {
659 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
660 host->name, host->address, message);
661 }
662
663
664
665 #ifndef DISABLE_EVENT
666 /*************************************************
667 * Post-defer action *
668 *************************************************/
669
670 /* This expands an arbitrary per-transport string.
671 It might, for example, be used to write to the database log.
672
673 Arguments:
674 addr the address item containing error information
675 host the current host
676
677 Returns: nothing
678 */
679
680 static void
681 deferred_event_raise(address_item *addr, host_item *host)
682 {
683 uschar * action = addr->transport->event_action;
684 const uschar * save_domain;
685 uschar * save_local;
686
687 if (!action)
688 return;
689
690 save_domain = deliver_domain;
691 save_local = deliver_localpart;
692
693 /*XXX would ip & port already be set up? */
694 deliver_host_address = string_copy(host->address);
695 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
696 event_defer_errno = addr->basic_errno;
697
698 router_name = addr->router->name;
699 transport_name = addr->transport->name;
700 deliver_domain = addr->domain;
701 deliver_localpart = addr->local_part;
702
703 (void) event_raise(action, US"msg:host:defer",
704 addr->message
705 ? addr->basic_errno > 0
706 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
707 : string_copy(addr->message)
708 : addr->basic_errno > 0
709 ? string_copy(US strerror(addr->basic_errno))
710 : NULL);
711
712 deliver_localpart = save_local;
713 deliver_domain = save_domain;
714 router_name = transport_name = NULL;
715 }
716 #endif
717
718 /*************************************************
719 * Synchronize SMTP responses *
720 *************************************************/
721
722 /* This function is called from smtp_deliver() to receive SMTP responses from
723 the server, and match them up with the commands to which they relate. When
724 PIPELINING is not in use, this function is called after every command, and is
725 therefore somewhat over-engineered, but it is simpler to use a single scheme
726 that works both with and without PIPELINING instead of having two separate sets
727 of code.
728
729 The set of commands that are buffered up with pipelining may start with MAIL
730 and may end with DATA; in between are RCPT commands that correspond to the
731 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
732 etc.) are never buffered.
733
734 Errors after MAIL or DATA abort the whole process leaving the response in the
735 buffer. After MAIL, pending responses are flushed, and the original command is
736 re-instated in big_buffer for error messages. For RCPT commands, the remote is
737 permitted to reject some recipient addresses while accepting others. However
738 certain errors clearly abort the whole process. Set the value in
739 transport_return to PENDING_OK if the address is accepted. If there is a
740 subsequent general error, it will get reset accordingly. If not, it will get
741 converted to OK at the end.
742
743 Arguments:
744 addrlist the complete address list
745 include_affixes TRUE if affixes include in RCPT
746 sync_addr ptr to the ptr of the one to start scanning at (updated)
747 host the host we are connected to
748 count the number of responses to read
749 address_retry_
750 include_sender true if 4xx retry is to include the sender it its key
751 pending_MAIL true if the first response is for MAIL
752 pending_DATA 0 if last command sent was not DATA
753 +1 if previously had a good recipient
754 -1 if not previously had a good recipient
755 inblock incoming SMTP block
756 timeout timeout value
757 buffer buffer for reading response
758 buffsize size of buffer
759
760 Returns: 3 if at least one address had 2xx and one had 5xx
761 2 if at least one address had 5xx but none had 2xx
762 1 if at least one host had a 2xx response, but none had 5xx
763 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
764 -1 timeout while reading RCPT response
765 -2 I/O or other non-response error for RCPT
766 -3 DATA or MAIL failed - errno and buffer set
767 */
768
769 static int
770 sync_responses(address_item *addrlist, BOOL include_affixes,
771 address_item **sync_addr, host_item *host, int count,
772 BOOL address_retry_include_sender, BOOL pending_MAIL,
773 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
774 int buffsize)
775 {
776 address_item *addr = *sync_addr;
777 int yield = 0;
778
779 /* Handle the response for a MAIL command. On error, reinstate the original
780 command in big_buffer for error message use, and flush any further pending
781 responses before returning, except after I/O errors and timeouts. */
782
783 if (pending_MAIL)
784 {
785 count--;
786 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
787 {
788 DEBUG(D_transport) debug_printf("bad response for MAIL\n");
789 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
790 if (errno == 0 && buffer[0] != 0)
791 {
792 uschar flushbuffer[4096];
793 int save_errno = 0;
794 if (buffer[0] == '4')
795 {
796 save_errno = ERRNO_MAIL4XX;
797 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
798 }
799 while (count-- > 0)
800 {
801 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
802 '2', timeout)
803 && (errno != 0 || flushbuffer[0] == 0))
804 break;
805 }
806 errno = save_errno;
807 }
808
809 if (pending_DATA) count--; /* Number of RCPT responses to come */
810 while (count-- > 0) /* Mark any pending addrs with the host used */
811 {
812 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
813 addr->host_used = host;
814 addr = addr->next;
815 }
816 return -3;
817 }
818 }
819
820 if (pending_DATA) count--; /* Number of RCPT responses to come */
821
822 /* Read and handle the required number of RCPT responses, matching each one up
823 with an address by scanning for the next address whose status is PENDING_DEFER.
824 */
825
826 while (count-- > 0)
827 {
828 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
829
830 /* The address was accepted */
831 addr->host_used = host;
832
833 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
834 {
835 yield |= 1;
836 addr->transport_return = PENDING_OK;
837
838 /* If af_dr_retry_exists is set, there was a routing delay on this address;
839 ensure that any address-specific retry record is expunged. We do this both
840 for the basic key and for the version that also includes the sender. */
841
842 if (testflag(addr, af_dr_retry_exists))
843 {
844 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
845 sender_address);
846 retry_add_item(addr, altkey, rf_delete);
847 retry_add_item(addr, addr->address_retry_key, rf_delete);
848 }
849 }
850
851 /* Timeout while reading the response */
852
853 else if (errno == ETIMEDOUT)
854 {
855 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
856 transport_rcpt_address(addr, include_affixes));
857 set_errno_nohost(addrlist, ETIMEDOUT, message, DEFER, FALSE);
858 retry_add_item(addr, addr->address_retry_key, 0);
859 update_waiting = FALSE;
860 return -1;
861 }
862
863 /* Handle other errors in obtaining an SMTP response by returning -1. This
864 will cause all the addresses to be deferred. Restore the SMTP command in
865 big_buffer for which we are checking the response, so the error message
866 makes sense. */
867
868 else if (errno != 0 || buffer[0] == 0)
869 {
870 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
871 transport_rcpt_address(addr, include_affixes));
872 return -2;
873 }
874
875 /* Handle SMTP permanent and temporary response codes. */
876
877 else
878 {
879 addr->message =
880 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
881 "%s", transport_rcpt_address(addr, include_affixes),
882 string_printing(buffer));
883 setflag(addr, af_pass_message);
884 msglog_line(host, addr->message);
885
886 /* The response was 5xx */
887
888 if (buffer[0] == '5')
889 {
890 addr->transport_return = FAIL;
891 yield |= 2;
892 }
893
894 /* The response was 4xx */
895
896 else
897 {
898 addr->transport_return = DEFER;
899 addr->basic_errno = ERRNO_RCPT4XX;
900 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
901
902 #ifndef DISABLE_EVENT
903 event_defer_errno = addr->more_errno;
904 msg_event_raise(US"msg:rcpt:host:defer", addr);
905 #endif
906
907 /* Log temporary errors if there are more hosts to be tried.
908 If not, log this last one in the == line. */
909
910 if (host->next)
911 log_write(0, LOG_MAIN, "H=%s [%s]: %s", host->name, host->address, addr->message);
912
913 #ifndef DISABLE_EVENT
914 else
915 msg_event_raise(US"msg:rcpt:defer", addr);
916 #endif
917
918 /* Do not put this message on the list of those waiting for specific
919 hosts, as otherwise it is likely to be tried too often. */
920
921 update_waiting = FALSE;
922
923 /* Add a retry item for the address so that it doesn't get tried again
924 too soon. If address_retry_include_sender is true, add the sender address
925 to the retry key. */
926
927 if (address_retry_include_sender)
928 {
929 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
930 sender_address);
931 retry_add_item(addr, altkey, 0);
932 }
933 else retry_add_item(addr, addr->address_retry_key, 0);
934 }
935 }
936 } /* Loop for next RCPT response */
937
938 /* Update where to start at for the next block of responses, unless we
939 have already handled all the addresses. */
940
941 if (addr != NULL) *sync_addr = addr->next;
942
943 /* Handle a response to DATA. If we have not had any good recipients, either
944 previously or in this block, the response is ignored. */
945
946 if (pending_DATA != 0 &&
947 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
948 {
949 int code;
950 uschar *msg;
951 BOOL pass_message;
952 if (pending_DATA > 0 || (yield & 1) != 0)
953 {
954 if (errno == 0 && buffer[0] == '4')
955 {
956 errno = ERRNO_DATA4XX;
957 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
958 }
959 return -3;
960 }
961 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
962 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
963 "is in use and there were no good recipients\n", msg);
964 }
965
966 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
967 present) received 3xx. If any RCPTs were handled and yielded anything other
968 than 4xx, yield will be set non-zero. */
969
970 return yield;
971 }
972
973
974
975 /* Do the client side of smtp-level authentication */
976 /*
977 Arguments:
978 buffer EHLO response from server (gets overwritten)
979 addrlist chain of potential addresses to deliver
980 host host to deliver to
981 ob transport options
982 ibp, obp comms channel control blocks
983
984 Returns:
985 OK Success, or failed (but not required): global "smtp_authenticated" set
986 DEFER Failed authentication (and was required)
987 ERROR Internal problem
988
989 FAIL_SEND Failed communications - transmit
990 FAIL - response
991 */
992
993 int
994 smtp_auth(uschar *buffer, unsigned bufsize, address_item *addrlist, host_item *host,
995 smtp_transport_options_block *ob, BOOL is_esmtp,
996 smtp_inblock *ibp, smtp_outblock *obp)
997 {
998 int require_auth;
999 uschar *fail_reason = US"server did not advertise AUTH support";
1000
1001 smtp_authenticated = FALSE;
1002 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
1003 require_auth = verify_check_given_host(&ob->hosts_require_auth, host);
1004
1005 if (is_esmtp && !regex_AUTH) regex_AUTH =
1006 regex_must_compile(US"\\n250[\\s\\-]AUTH\\s+([\\-\\w\\s]+)(?:\\n|$)",
1007 FALSE, TRUE);
1008
1009 if (is_esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
1010 {
1011 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
1012 expand_nmax = -1; /* reset */
1013
1014 /* Must not do this check until after we have saved the result of the
1015 regex match above. */
1016
1017 if (require_auth == OK ||
1018 verify_check_given_host(&ob->hosts_try_auth, host) == OK)
1019 {
1020 auth_instance *au;
1021 fail_reason = US"no common mechanisms were found";
1022
1023 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1024
1025 /* Scan the configured authenticators looking for one which is configured
1026 for use as a client, which is not suppressed by client_condition, and
1027 whose name matches an authentication mechanism supported by the server.
1028 If one is found, attempt to authenticate by calling its client function.
1029 */
1030
1031 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1032 {
1033 uschar *p = names;
1034 if (!au->client ||
1035 (au->client_condition != NULL &&
1036 !expand_check_condition(au->client_condition, au->name,
1037 US"client authenticator")))
1038 {
1039 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1040 au->name,
1041 (au->client)? "client_condition is false" :
1042 "not configured as a client");
1043 continue;
1044 }
1045
1046 /* Loop to scan supported server mechanisms */
1047
1048 while (*p != 0)
1049 {
1050 int rc;
1051 int len = Ustrlen(au->public_name);
1052 while (isspace(*p)) p++;
1053
1054 if (strncmpic(au->public_name, p, len) != 0 ||
1055 (p[len] != 0 && !isspace(p[len])))
1056 {
1057 while (*p != 0 && !isspace(*p)) p++;
1058 continue;
1059 }
1060
1061 /* Found data for a listed mechanism. Call its client entry. Set
1062 a flag in the outblock so that data is overwritten after sending so
1063 that reflections don't show it. */
1064
1065 fail_reason = US"authentication attempt(s) failed";
1066 obp->authenticating = TRUE;
1067 rc = (au->info->clientcode)(au, ibp, obp,
1068 ob->command_timeout, buffer, bufsize);
1069 obp->authenticating = FALSE;
1070 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1071 au->name, rc);
1072
1073 /* A temporary authentication failure must hold up delivery to
1074 this host. After a permanent authentication failure, we carry on
1075 to try other authentication methods. If all fail hard, try to
1076 deliver the message unauthenticated unless require_auth was set. */
1077
1078 switch(rc)
1079 {
1080 case OK:
1081 smtp_authenticated = TRUE; /* stops the outer loop */
1082 client_authenticator = au->name;
1083 if (au->set_client_id != NULL)
1084 client_authenticated_id = expand_string(au->set_client_id);
1085 break;
1086
1087 /* Failure after writing a command */
1088
1089 case FAIL_SEND:
1090 return FAIL_SEND;
1091
1092 /* Failure after reading a response */
1093
1094 case FAIL:
1095 if (errno != 0 || buffer[0] != '5') return FAIL;
1096 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1097 au->name, host->name, host->address, buffer);
1098 break;
1099
1100 /* Failure by some other means. In effect, the authenticator
1101 decided it wasn't prepared to handle this case. Typically this
1102 is the result of "fail" in an expansion string. Do we need to
1103 log anything here? Feb 2006: a message is now put in the buffer
1104 if logging is required. */
1105
1106 case CANCELLED:
1107 if (*buffer != 0)
1108 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1109 "authentication H=%s [%s] %s", au->name, host->name,
1110 host->address, buffer);
1111 break;
1112
1113 /* Internal problem, message in buffer. */
1114
1115 case ERROR:
1116 set_errno_nohost(addrlist, ERRNO_AUTHPROB, string_copy(buffer),
1117 DEFER, FALSE);
1118 return ERROR;
1119 }
1120
1121 break; /* If not authenticated, try next authenticator */
1122 } /* Loop for scanning supported server mechanisms */
1123 } /* Loop for further authenticators */
1124 }
1125 }
1126
1127 /* If we haven't authenticated, but are required to, give up. */
1128
1129 if (require_auth == OK && !smtp_authenticated)
1130 {
1131 set_errno_nohost(addrlist, ERRNO_AUTHFAIL,
1132 string_sprintf("authentication required but %s", fail_reason), DEFER,
1133 FALSE);
1134 return DEFER;
1135 }
1136
1137 return OK;
1138 }
1139
1140
1141 /* Construct AUTH appendix string for MAIL TO */
1142 /*
1143 Arguments
1144 buffer to build string
1145 addrlist chain of potential addresses to deliver
1146 ob transport options
1147
1148 Globals smtp_authenticated
1149 client_authenticated_sender
1150 Return True on error, otherwise buffer has (possibly empty) terminated string
1151 */
1152
1153 BOOL
1154 smtp_mail_auth_str(uschar *buffer, unsigned bufsize, address_item *addrlist,
1155 smtp_transport_options_block *ob)
1156 {
1157 uschar *local_authenticated_sender = authenticated_sender;
1158
1159 #ifdef notdef
1160 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n", authenticated_sender, ob->authenticated_sender, smtp_authenticated?"Y":"N");
1161 #endif
1162
1163 if (ob->authenticated_sender != NULL)
1164 {
1165 uschar *new = expand_string(ob->authenticated_sender);
1166 if (new == NULL)
1167 {
1168 if (!expand_string_forcedfail)
1169 {
1170 uschar *message = string_sprintf("failed to expand "
1171 "authenticated_sender: %s", expand_string_message);
1172 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1173 return TRUE;
1174 }
1175 }
1176 else if (new[0] != 0) local_authenticated_sender = new;
1177 }
1178
1179 /* Add the authenticated sender address if present */
1180
1181 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1182 local_authenticated_sender != NULL)
1183 {
1184 string_format(buffer, bufsize, " AUTH=%s",
1185 auth_xtextencode(local_authenticated_sender,
1186 Ustrlen(local_authenticated_sender)));
1187 client_authenticated_sender = string_copy(local_authenticated_sender);
1188 }
1189 else
1190 *buffer= 0;
1191
1192 return FALSE;
1193 }
1194
1195
1196
1197 #ifdef EXPERIMENTAL_DANE
1198 /* Lookup TLSA record for host/port.
1199 Return: OK success with dnssec; DANE mode
1200 DEFER Do not use this host now, may retry later
1201 FAIL_FORCED No TLSA record; DANE not usable
1202 FAIL Do not use this connection
1203 */
1204
1205 int
1206 tlsa_lookup(const host_item * host, dns_answer * dnsa, BOOL dane_required)
1207 {
1208 /* move this out to host.c given the similarity to dns_lookup() ? */
1209 uschar buffer[300];
1210 const uschar * fullname = buffer;
1211
1212 /* TLSA lookup string */
1213 (void)sprintf(CS buffer, "_%d._tcp.%.256s", host->port, host->name);
1214
1215 switch (dns_lookup(dnsa, buffer, T_TLSA, &fullname))
1216 {
1217 case DNS_SUCCEED:
1218 if (!dns_is_secure(dnsa))
1219 {
1220 log_write(0, LOG_MAIN, "DANE error: TLSA lookup not DNSSEC");
1221 return DEFER;
1222 }
1223 return OK;
1224
1225 case DNS_AGAIN:
1226 return DEFER; /* just defer this TLS'd conn */
1227
1228 case DNS_NODATA: /* no TLSA RR for this lookup */
1229 case DNS_NOMATCH: /* no records at all for this lookup */
1230 return dane_required ? FAIL : FAIL_FORCED;
1231
1232 default:
1233 case DNS_FAIL:
1234 return dane_required ? FAIL : DEFER;
1235 }
1236 }
1237 #endif
1238
1239
1240
1241 typedef struct smtp_compare_s
1242 {
1243 uschar *current_sender_address;
1244 struct transport_instance *tblock;
1245 } smtp_compare_t;
1246
1247 /*
1248 Create a unique string that identifies this message, it is based on
1249 sender_address, helo_data and tls_certificate if enabled. */
1250
1251 static uschar *
1252 smtp_local_identity(uschar * sender, struct transport_instance * tblock)
1253 {
1254 address_item * addr1;
1255 uschar * if1 = US"";
1256 uschar * helo1 = US"";
1257 #ifdef SUPPORT_TLS
1258 uschar * tlsc1 = US"";
1259 #endif
1260 uschar * save_sender_address = sender_address;
1261 uschar * local_identity = NULL;
1262 smtp_transport_options_block * ob =
1263 (smtp_transport_options_block *)tblock->options_block;
1264
1265 sender_address = sender;
1266
1267 addr1 = deliver_make_addr (sender, TRUE);
1268 deliver_set_expansions(addr1);
1269
1270 if (ob->interface)
1271 if1 = expand_string(ob->interface);
1272
1273 if (ob->helo_data)
1274 helo1 = expand_string(ob->helo_data);
1275
1276 #ifdef SUPPORT_TLS
1277 if (ob->tls_certificate)
1278 tlsc1 = expand_string(ob->tls_certificate);
1279 local_identity = string_sprintf ("%s^%s^%s", if1, helo1, tlsc1);
1280 #else
1281 local_identity = string_sprintf ("%s^%s", if1, helo1);
1282 #endif
1283
1284 deliver_set_expansions(NULL);
1285 sender_address = save_sender_address;
1286
1287 return local_identity;
1288 }
1289
1290
1291
1292 /* This routine is a callback that is called from transport_check_waiting.
1293 This function will evaluate the incoming message versus the previous
1294 message. If the incoming message is using a different local identity then
1295 we will veto this new message. */
1296
1297 static BOOL
1298 smtp_are_same_identities(uschar * message_id, smtp_compare_t * s_compare)
1299 {
1300 uschar * message_local_identity,
1301 * current_local_identity,
1302 * new_sender_address;
1303
1304 current_local_identity =
1305 smtp_local_identity(s_compare->current_sender_address, s_compare->tblock);
1306
1307 if (!(new_sender_address = deliver_get_sender_address(message_id)))
1308 return 0;
1309
1310 message_local_identity =
1311 smtp_local_identity(new_sender_address, s_compare->tblock);
1312
1313 return Ustrcmp(current_local_identity, message_local_identity) == 0;
1314 }
1315
1316
1317
1318 uschar
1319 ehlo_response(uschar * buf, size_t bsize, uschar checks)
1320 {
1321 #ifdef SUPPORT_TLS
1322 if ( checks & PEER_OFFERED_TLS
1323 && pcre_exec(regex_STARTTLS, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1324 checks &= ~PEER_OFFERED_TLS;
1325 #endif
1326
1327 if ( checks & PEER_OFFERED_IGNQ
1328 && pcre_exec(regex_IGNOREQUOTA, NULL, CS buf, bsize, 0,
1329 PCRE_EOPT, NULL, 0) < 0)
1330 checks &= ~PEER_OFFERED_IGNQ;
1331
1332 if ( checks & PEER_OFFERED_CHUNKING
1333 && pcre_exec(regex_CHUNKING, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1334 checks &= ~PEER_OFFERED_CHUNKING;
1335
1336 #ifndef DISABLE_PRDR
1337 if ( checks & PEER_OFFERED_PRDR
1338 && pcre_exec(regex_PRDR, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1339 checks &= ~PEER_OFFERED_PRDR;
1340 #endif
1341
1342 #ifdef SUPPORT_I18N
1343 if ( checks & PEER_OFFERED_UTF8
1344 && pcre_exec(regex_UTF8, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1345 checks &= ~PEER_OFFERED_UTF8;
1346 #endif
1347
1348 if ( checks & PEER_OFFERED_DSN
1349 && pcre_exec(regex_DSN, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1350 checks &= ~PEER_OFFERED_DSN;
1351
1352 if ( checks & PEER_OFFERED_PIPE
1353 && pcre_exec(regex_PIPELINING, NULL, CS buf, bsize, 0,
1354 PCRE_EOPT, NULL, 0) < 0)
1355 checks &= ~PEER_OFFERED_PIPE;
1356
1357 if ( checks & PEER_OFFERED_SIZE
1358 && pcre_exec(regex_SIZE, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1359 checks &= ~PEER_OFFERED_SIZE;
1360
1361 return checks;
1362 }
1363
1364
1365
1366 /* Callback for emitting a BDAT data chunk header.
1367
1368 If given a nonzero size, first flush any buffered SMTP commands
1369 then emit the command.
1370
1371 Reap previous SMTP command responses if requested.
1372 Reap one SMTP command response if requested.
1373
1374 Returns: OK or ERROR
1375 */
1376
1377 static int
1378 smtp_chunk_cmd_callback(int fd, transport_ctx * tctx,
1379 unsigned chunk_size, unsigned flags)
1380 {
1381 smtp_transport_options_block * ob =
1382 (smtp_transport_options_block *)(tctx->tblock->options_block);
1383 int cmd_count = 0;
1384 int prev_cmd_count;
1385 uschar * buffer = tctx->buffer;
1386
1387
1388 /* Write SMTP chunk header command */
1389
1390 if (chunk_size > 0)
1391 if((cmd_count = smtp_write_command(tctx->outblock, FALSE, "BDAT %u%s\r\n",
1392 chunk_size,
1393 flags & tc_chunk_last ? " LAST" : "")
1394 ) < 0) return ERROR;
1395
1396 prev_cmd_count = cmd_count += tctx->cmd_count;
1397
1398 /* Reap responses for any previous, but not one we just emitted */
1399
1400 if (chunk_size > 0)
1401 prev_cmd_count--;
1402 if (tctx->pending_BDAT)
1403 prev_cmd_count--;
1404
1405 if (flags & tc_reap_prev && prev_cmd_count > 0)
1406 {
1407 DEBUG(D_transport) debug_printf("look for %d responses"
1408 " for previous pipelined cmds\n", prev_cmd_count);
1409
1410 switch(sync_responses(tctx->first_addr, tctx->tblock->rcpt_include_affixes,
1411 tctx->sync_addr, tctx->host, prev_cmd_count,
1412 ob->address_retry_include_sender,
1413 tctx->pending_MAIL, 0,
1414 tctx->inblock,
1415 ob->command_timeout,
1416 buffer, DELIVER_BUFFER_SIZE))
1417 {
1418 case 1: /* 2xx (only) => OK */
1419 case 3: tctx->good_RCPT = TRUE; /* 2xx & 5xx => OK & progress made */
1420 case 2: *tctx->completed_address = TRUE; /* 5xx (only) => progress made */
1421 case 0: break; /* No 2xx or 5xx, but no probs */
1422
1423 case -1: /* Timeout on RCPT */
1424 default: return ERROR; /* I/O error, or any MAIL/DATA error */
1425 }
1426 cmd_count = 1;
1427 if (!tctx->pending_BDAT)
1428 pipelining_active = FALSE;
1429 }
1430
1431 /* Reap response for an outstanding BDAT */
1432
1433 if (tctx->pending_BDAT)
1434 {
1435 DEBUG(D_transport) debug_printf("look for one response for BDAT\n");
1436
1437 if (!smtp_read_response(tctx->inblock, buffer, DELIVER_BUFFER_SIZE, '2',
1438 ob->command_timeout))
1439 {
1440 if (errno == 0 && buffer[0] == '4')
1441 {
1442 errno = ERRNO_DATA4XX; /*XXX does this actually get used? */
1443 tctx->first_addr->more_errno |=
1444 ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1445 }
1446 return ERROR;
1447 }
1448 cmd_count--;
1449 tctx->pending_BDAT = FALSE;
1450 pipelining_active = FALSE;
1451 }
1452 else if (chunk_size > 0)
1453 tctx->pending_BDAT = TRUE;
1454
1455
1456 tctx->cmd_count = cmd_count;
1457 return OK;
1458 }
1459
1460
1461
1462 /*************************************************
1463 * Deliver address list to given host *
1464 *************************************************/
1465
1466 /* If continue_hostname is not null, we get here only when continuing to
1467 deliver down an existing channel. The channel was passed as the standard
1468 input. TLS is never active on a passed channel; the previous process always
1469 closes it down before passing the connection on.
1470
1471 Otherwise, we have to make a connection to the remote host, and do the
1472 initial protocol exchange.
1473
1474 When running as an MUA wrapper, if the sender or any recipient is rejected,
1475 temporarily or permanently, we force failure for all recipients.
1476
1477 Arguments:
1478 addrlist chain of potential addresses to deliver; only those whose
1479 transport_return field is set to PENDING_DEFER are currently
1480 being processed; others should be skipped - they have either
1481 been delivered to an earlier host or IP address, or been
1482 failed by one of them.
1483 host host to deliver to
1484 host_af AF_INET or AF_INET6
1485 port default TCP/IP port to use, in host byte order
1486 interface interface to bind to, or NULL
1487 tblock transport instance block
1488 message_defer set TRUE if yield is OK, but all addresses were deferred
1489 because of a non-recipient, non-host failure, that is, a
1490 4xx response to MAIL FROM, DATA, or ".". This is a defer
1491 that is specific to the message.
1492 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1493 a second attempt after TLS initialization fails
1494
1495 Returns: OK - the connection was made and the delivery attempted;
1496 the result for each address is in its data block.
1497 DEFER - the connection could not be made, or something failed
1498 while setting up the SMTP session, or there was a
1499 non-message-specific error, such as a timeout.
1500 ERROR - a filter command is specified for this transport,
1501 and there was a problem setting it up; OR helo_data
1502 or add_headers or authenticated_sender is specified
1503 for this transport, and the string failed to expand
1504 */
1505
1506 static int
1507 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
1508 uschar *interface, transport_instance *tblock,
1509 BOOL *message_defer, BOOL suppress_tls)
1510 {
1511 address_item *addr;
1512 address_item *sync_addr;
1513 address_item *first_addr = addrlist;
1514 int yield = OK;
1515 int address_count;
1516 int save_errno;
1517 int rc;
1518 time_t start_delivery_time = time(NULL);
1519 smtp_transport_options_block *ob =
1520 (smtp_transport_options_block *)(tblock->options_block);
1521 struct lflags {
1522 BOOL lmtp:1;
1523 BOOL smtps:1;
1524 BOOL ok:1;
1525 BOOL send_rset:1;
1526 BOOL send_quit:1;
1527 BOOL setting_up:1;
1528 BOOL esmtp:1;
1529 BOOL esmtp_sent:1;
1530 BOOL pending_MAIL:1;
1531 #ifndef DISABLE_PRDR
1532 BOOL prdr_active:1;
1533 #endif
1534 #ifdef SUPPORT_I18N
1535 BOOL utf8_needed:1;
1536 #endif
1537 BOOL dsn_all_lasthop:1;
1538 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1539 BOOL dane:1;
1540 BOOL dane_required:1;
1541 #endif
1542 } lflags;
1543
1544 BOOL pass_message = FALSE;
1545 BOOL completed_address = FALSE;
1546 uschar peer_offered = 0;
1547 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1548 dns_answer tlsa_dnsa;
1549 #endif
1550 smtp_inblock inblock;
1551 smtp_outblock outblock;
1552 int max_rcpt = tblock->max_addresses;
1553 uschar *igquotstr = US"";
1554
1555 #ifdef EXPERIMENTAL_DSN_INFO
1556 uschar *smtp_greeting = NULL;
1557 uschar *helo_response = NULL;
1558 #endif
1559 uschar *helo_data = NULL;
1560
1561 uschar *message = NULL;
1562 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
1563 uschar *p;
1564 uschar buffer[DELIVER_BUFFER_SIZE];
1565 uschar inbuffer[4096];
1566 uschar outbuffer[4096];
1567
1568 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
1569
1570 lflags.lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
1571 lflags.smtps = strcmpic(ob->protocol, US"smtps") == 0;
1572 lflags.ok = FALSE;
1573 lflags.send_rset = TRUE;
1574 lflags.send_quit = TRUE;
1575 lflags.setting_up = TRUE;
1576 lflags.esmtp = TRUE;
1577 lflags.esmtp_sent = FALSE;
1578 #ifdef SUPPORT_I18N
1579 lflags.utf8_needed = FALSE;
1580 #endif
1581 lflags.dsn_all_lasthop = TRUE;
1582 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1583 lflags.dane = FALSE;
1584 lflags.dane_required = verify_check_given_host(&ob->hosts_require_dane, host) == OK;
1585 #endif
1586
1587 *message_defer = FALSE;
1588 smtp_command = US"initial connection";
1589 if (max_rcpt == 0) max_rcpt = 999999;
1590
1591 /* Set up the buffer for reading SMTP response packets. */
1592
1593 inblock.buffer = inbuffer;
1594 inblock.buffersize = sizeof(inbuffer);
1595 inblock.ptr = inbuffer;
1596 inblock.ptrend = inbuffer;
1597
1598 /* Set up the buffer for holding SMTP commands while pipelining */
1599
1600 outblock.buffer = outbuffer;
1601 outblock.buffersize = sizeof(outbuffer);
1602 outblock.ptr = outbuffer;
1603 outblock.cmd_count = 0;
1604 outblock.authenticating = FALSE;
1605
1606 /* Reset the parameters of a TLS session. */
1607
1608 tls_out.bits = 0;
1609 tls_out.cipher = NULL; /* the one we may use for this transport */
1610 tls_out.ourcert = NULL;
1611 tls_out.peercert = NULL;
1612 tls_out.peerdn = NULL;
1613 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1614 tls_out.sni = NULL;
1615 #endif
1616 tls_out.ocsp = OCSP_NOT_REQ;
1617
1618 /* Flip the legacy TLS-related variables over to the outbound set in case
1619 they're used in the context of the transport. Don't bother resetting
1620 afterward as we're in a subprocess. */
1621
1622 tls_modify_variables(&tls_out);
1623
1624 #ifndef SUPPORT_TLS
1625 if (lflags.smtps)
1626 {
1627 set_errno_nohost(addrlist, ERRNO_TLSFAILURE, US"TLS support not available",
1628 DEFER, FALSE);
1629 return ERROR;
1630 }
1631 #endif
1632
1633 /* Make a connection to the host if this isn't a continued delivery, and handle
1634 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
1635 specially so they can be identified for retries. */
1636
1637 if (continue_hostname == NULL)
1638 {
1639 /* This puts port into host->port */
1640 inblock.sock = outblock.sock =
1641 smtp_connect(host, host_af, port, interface, ob->connect_timeout, tblock);
1642
1643 if (inblock.sock < 0)
1644 {
1645 set_errno_nohost(addrlist, errno == ETIMEDOUT ? ERRNO_CONNECTTIMEOUT : errno,
1646 NULL, DEFER, FALSE);
1647 return DEFER;
1648 }
1649
1650 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1651 {
1652 tls_out.dane_verified = FALSE;
1653 tls_out.tlsa_usage = 0;
1654
1655 if (host->dnssec == DS_YES)
1656 {
1657 if( lflags.dane_required
1658 || verify_check_given_host(&ob->hosts_try_dane, host) == OK
1659 )
1660 switch (rc = tlsa_lookup(host, &tlsa_dnsa, lflags.dane_required))
1661 {
1662 case OK: lflags.dane = TRUE; break;
1663 case FAIL_FORCED: break;
1664 default: set_errno_nohost(addrlist, ERRNO_DNSDEFER,
1665 string_sprintf("DANE error: tlsa lookup %s",
1666 rc == DEFER ? "DEFER" : "FAIL"),
1667 rc, FALSE);
1668 return rc;
1669 }
1670 }
1671 else if (lflags.dane_required)
1672 {
1673 set_errno_nohost(addrlist, ERRNO_DNSDEFER,
1674 string_sprintf("DANE error: %s lookup not DNSSEC", host->name),
1675 FAIL, FALSE);
1676 return FAIL;
1677 }
1678
1679 if (lflags.dane)
1680 ob->tls_tempfail_tryclear = FALSE;
1681 }
1682 #endif /*DANE*/
1683
1684 /* Expand the greeting message while waiting for the initial response. (Makes
1685 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1686 delayed till here so that $sending_interface and $sending_port are set. */
1687
1688 helo_data = expand_string(ob->helo_data);
1689 #ifdef SUPPORT_I18N
1690 if (helo_data)
1691 {
1692 uschar * errstr = NULL;
1693 if ((helo_data = string_domain_utf8_to_alabel(helo_data, &errstr)), errstr)
1694 {
1695 errstr = string_sprintf("failed to expand helo_data: %s", errstr);
1696 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE);
1697 yield = DEFER;
1698 goto SEND_QUIT;
1699 }
1700 }
1701 #endif
1702
1703 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1704 is nevertheless a reasonably clean way of programming this kind of logic,
1705 where you want to escape on any error. */
1706
1707 if (!lflags.smtps)
1708 {
1709 BOOL good_response;
1710
1711 #ifdef TCP_QUICKACK
1712 (void) setsockopt(inblock.sock, IPPROTO_TCP, TCP_QUICKACK, US &off, sizeof(off));
1713 #endif
1714 good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
1715 '2', ob->command_timeout);
1716 #ifdef EXPERIMENTAL_DSN_INFO
1717 smtp_greeting = string_copy(buffer);
1718 #endif
1719 if (!good_response) goto RESPONSE_FAILED;
1720
1721 #ifndef DISABLE_EVENT
1722 {
1723 uschar * s;
1724 lookup_dnssec_authenticated = host->dnssec==DS_YES ? US"yes"
1725 : host->dnssec==DS_NO ? US"no" : NULL;
1726 s = event_raise(tblock->event_action, US"smtp:connect", buffer);
1727 if (s)
1728 {
1729 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL,
1730 string_sprintf("deferred by smtp:connect event expansion: %s", s),
1731 DEFER, FALSE);
1732 yield = DEFER;
1733 goto SEND_QUIT;
1734 }
1735 }
1736 #endif
1737
1738 /* Now check if the helo_data expansion went well, and sign off cleanly if
1739 it didn't. */
1740
1741 if (!helo_data)
1742 {
1743 uschar *message = string_sprintf("failed to expand helo_data: %s",
1744 expand_string_message);
1745 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1746 yield = DEFER;
1747 goto SEND_QUIT;
1748 }
1749 }
1750
1751 /** Debugging without sending a message
1752 addrlist->transport_return = DEFER;
1753 goto SEND_QUIT;
1754 **/
1755
1756 /* Errors that occur after this point follow an SMTP command, which is
1757 left in big_buffer by smtp_write_command() for use in error messages. */
1758
1759 smtp_command = big_buffer;
1760
1761 /* Tell the remote who we are...
1762
1763 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1764 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1765 greeting is of this form. The assumption was that the far end supports it
1766 properly... but experience shows that there are some that give 5xx responses,
1767 even though the banner includes "ESMTP" (there's a bloody-minded one that
1768 says "ESMTP not spoken here"). Cope with that case.
1769
1770 September 2000: Time has passed, and it seems reasonable now to always send
1771 EHLO at the start. It is also convenient to make the change while installing
1772 the TLS stuff.
1773
1774 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1775 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1776 would be no way to send out the mails, so there is now a host list
1777 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1778 PIPELINING problem as well. Maybe it can also be useful to cure other
1779 problems with broken servers.
1780
1781 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1782 Then somebody tried it with a Microsoft mailer... It seems that all other
1783 mailers use upper case for some reason (the RFC is quite clear about case
1784 independence) so, for peace of mind, I gave in. */
1785
1786 lflags.esmtp = verify_check_given_host(&ob->hosts_avoid_esmtp, host) != OK;
1787
1788 /* Alas; be careful, since this goto is not an error-out, so conceivably
1789 we might set data between here and the target which we assume to exist
1790 and be usable. I can see this coming back to bite us. */
1791 #ifdef SUPPORT_TLS
1792 if (lflags.smtps)
1793 {
1794 smtp_peer_options |= PEER_OFFERED_TLS;
1795 suppress_tls = FALSE;
1796 ob->tls_tempfail_tryclear = FALSE;
1797 smtp_command = US"SSL-on-connect";
1798 goto TLS_NEGOTIATE;
1799 }
1800 #endif
1801
1802 if (lflags.esmtp)
1803 {
1804 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1805 lflags.lmtp ? "LHLO" : "EHLO", helo_data) < 0)
1806 goto SEND_FAILED;
1807 lflags.esmtp_sent = TRUE;
1808 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1809 ob->command_timeout))
1810 {
1811 if (errno != 0 || buffer[0] == 0 || lflags.lmtp)
1812 {
1813 #ifdef EXPERIMENTAL_DSN_INFO
1814 helo_response = string_copy(buffer);
1815 #endif
1816 goto RESPONSE_FAILED;
1817 }
1818 lflags.esmtp = FALSE;
1819 }
1820 #ifdef EXPERIMENTAL_DSN_INFO
1821 helo_response = string_copy(buffer);
1822 #endif
1823 }
1824 else
1825 DEBUG(D_transport)
1826 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1827
1828 if (!lflags.esmtp)
1829 {
1830 BOOL good_response;
1831 int n = sizeof(buffer);
1832 uschar * rsp = buffer;
1833
1834 if (lflags.esmtp_sent && (n = Ustrlen(buffer)) < sizeof(buffer)/2)
1835 { rsp = buffer + n + 1; n = sizeof(buffer) - n; }
1836
1837 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1838 goto SEND_FAILED;
1839 good_response = smtp_read_response(&inblock, rsp, n,
1840 '2', ob->command_timeout);
1841 #ifdef EXPERIMENTAL_DSN_INFO
1842 helo_response = string_copy(rsp);
1843 #endif
1844 if (!good_response)
1845 {
1846 /* Handle special logging for a closed connection after HELO
1847 when had previously sent EHLO */
1848
1849 if (rsp != buffer && rsp[0] == 0 && (errno == 0 || errno == ECONNRESET))
1850 {
1851 message = NULL;
1852 lflags.send_quit = FALSE;
1853 save_errno = ERRNO_SMTPCLOSED;
1854 message = string_sprintf("Remote host closed connection "
1855 "in response to %s (EHLO response was: %s)",
1856 smtp_command, buffer);
1857 goto FAILED;
1858 }
1859 Ustrncpy(buffer, rsp, sizeof(buffer)/2);
1860 goto RESPONSE_FAILED;
1861 }
1862 }
1863
1864 peer_offered = smtp_peer_options = 0;
1865
1866 if (lflags.esmtp || lflags.lmtp)
1867 {
1868 peer_offered = ehlo_response(buffer, Ustrlen(buffer),
1869 PEER_OFFERED_TLS /* others checked later */
1870 );
1871
1872 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1873
1874 #ifdef SUPPORT_TLS
1875 smtp_peer_options |= peer_offered & PEER_OFFERED_TLS;
1876 #endif
1877 }
1878 }
1879
1880 /* For continuing deliveries down the same channel, the socket is the standard
1881 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1882 below). Set up the pointer to where subsequent commands will be left, for
1883 error messages. Note that smtp_peer_options will have been
1884 set from the command line if they were set in the process that passed the
1885 connection on. */
1886
1887 /*XXX continue case needs to propagate DSN_INFO, prob. in deliver.c
1888 as the contine goes via transport_pass_socket() and doublefork and exec.
1889 It does not wait. Unclear how we keep separate host's responses
1890 separate - we could match up by host ip+port as a bodge. */
1891
1892 else
1893 {
1894 inblock.sock = outblock.sock = fileno(stdin);
1895 smtp_command = big_buffer;
1896 host->port = port; /* Record the port that was used */
1897 }
1898
1899 /* If TLS is available on this connection, whether continued or not, attempt to
1900 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1901 send another EHLO - the server may give a different answer in secure mode. We
1902 use a separate buffer for reading the response to STARTTLS so that if it is
1903 negative, the original EHLO data is available for subsequent analysis, should
1904 the client not be required to use TLS. If the response is bad, copy the buffer
1905 for error analysis. */
1906
1907 #ifdef SUPPORT_TLS
1908 if ( smtp_peer_options & PEER_OFFERED_TLS
1909 && !suppress_tls
1910 && verify_check_given_host(&ob->hosts_avoid_tls, host) != OK)
1911 {
1912 uschar buffer2[4096];
1913 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1914 goto SEND_FAILED;
1915
1916 /* If there is an I/O error, transmission of this message is deferred. If
1917 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1918 false, we also defer. However, if there is a temporary rejection of STARTTLS
1919 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1920 STARTTLS, we carry on. This means we will try to send the message in clear,
1921 unless the host is in hosts_require_tls (tested below). */
1922
1923 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1924 ob->command_timeout))
1925 {
1926 if ( errno != 0
1927 || buffer2[0] == 0
1928 || (buffer2[0] == '4' && !ob->tls_tempfail_tryclear)
1929 )
1930 {
1931 Ustrncpy(buffer, buffer2, sizeof(buffer));
1932 goto RESPONSE_FAILED;
1933 }
1934 }
1935
1936 /* STARTTLS accepted: try to negotiate a TLS session. */
1937
1938 else
1939 TLS_NEGOTIATE:
1940 {
1941 int rc = tls_client_start(inblock.sock, host, addrlist, tblock
1942 # ifdef EXPERIMENTAL_DANE
1943 , lflags.dane ? &tlsa_dnsa : NULL
1944 # endif
1945 );
1946
1947 /* TLS negotiation failed; give an error. From outside, this function may
1948 be called again to try in clear on a new connection, if the options permit
1949 it for this host. */
1950
1951 if (rc != OK)
1952 {
1953 # ifdef EXPERIMENTAL_DANE
1954 if (lflags.dane) log_write(0, LOG_MAIN,
1955 "DANE attempt failed; no TLS connection to %s [%s]",
1956 host->name, host->address);
1957 # endif
1958
1959 save_errno = ERRNO_TLSFAILURE;
1960 message = US"failure while setting up TLS session";
1961 lflags.send_quit = FALSE;
1962 goto TLS_FAILED;
1963 }
1964
1965 /* TLS session is set up */
1966
1967 smtp_peer_options_wrap = smtp_peer_options;
1968 for (addr = addrlist; addr; addr = addr->next)
1969 if (addr->transport_return == PENDING_DEFER)
1970 {
1971 addr->cipher = tls_out.cipher;
1972 addr->ourcert = tls_out.ourcert;
1973 addr->peercert = tls_out.peercert;
1974 addr->peerdn = tls_out.peerdn;
1975 addr->ocsp = tls_out.ocsp;
1976 }
1977 }
1978 }
1979
1980 /* if smtps, we'll have smtp_command set to something else; always safe to
1981 reset it here. */
1982 smtp_command = big_buffer;
1983
1984 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1985 helo_data is null, we are dealing with a connection that was passed from
1986 another process, and so we won't have expanded helo_data above. We have to
1987 expand it here. $sending_ip_address and $sending_port are set up right at the
1988 start of the Exim process (in exim.c). */
1989
1990 if (tls_out.active >= 0)
1991 {
1992 char *greeting_cmd;
1993 BOOL good_response;
1994
1995 if (helo_data == NULL)
1996 {
1997 helo_data = expand_string(ob->helo_data);
1998 if (helo_data == NULL)
1999 {
2000 uschar *message = string_sprintf("failed to expand helo_data: %s",
2001 expand_string_message);
2002 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
2003 yield = DEFER;
2004 goto SEND_QUIT;
2005 }
2006 }
2007
2008 /* For SMTPS we need to wait for the initial OK response. */
2009 if (lflags.smtps)
2010 {
2011 good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
2012 '2', ob->command_timeout);
2013 #ifdef EXPERIMENTAL_DSN_INFO
2014 smtp_greeting = string_copy(buffer);
2015 #endif
2016 if (!good_response) goto RESPONSE_FAILED;
2017 }
2018
2019 if (lflags.esmtp)
2020 greeting_cmd = "EHLO";
2021 else
2022 {
2023 greeting_cmd = "HELO";
2024 DEBUG(D_transport)
2025 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
2026 }
2027
2028 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
2029 lflags.lmtp ? "LHLO" : greeting_cmd, helo_data) < 0)
2030 goto SEND_FAILED;
2031 good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
2032 '2', ob->command_timeout);
2033 #ifdef EXPERIMENTAL_DSN_INFO
2034 helo_response = string_copy(buffer);
2035 #endif
2036 if (!good_response) goto RESPONSE_FAILED;
2037 smtp_peer_options = 0;
2038 }
2039
2040 /* If the host is required to use a secure channel, ensure that we
2041 have one. */
2042
2043 else if ( lflags.smtps
2044 # ifdef EXPERIMENTAL_DANE
2045 || lflags.dane
2046 # endif
2047 || verify_check_given_host(&ob->hosts_require_tls, host) == OK
2048 )
2049 {
2050 save_errno = ERRNO_TLSREQUIRED;
2051 message = string_sprintf("a TLS session is required, but %s",
2052 smtp_peer_options & PEER_OFFERED_TLS
2053 ? "an attempt to start TLS failed" : "the server did not offer TLS support");
2054 goto TLS_FAILED;
2055 }
2056 #endif /*SUPPORT_TLS*/
2057
2058 /* If TLS is active, we have just started it up and re-done the EHLO command,
2059 so its response needs to be analyzed. If TLS is not active and this is a
2060 continued session down a previously-used socket, we haven't just done EHLO, so
2061 we skip this. */
2062
2063 if (continue_hostname == NULL
2064 #ifdef SUPPORT_TLS
2065 || tls_out.active >= 0
2066 #endif
2067 )
2068 {
2069 if (lflags.esmtp || lflags.lmtp)
2070 {
2071 peer_offered = ehlo_response(buffer, Ustrlen(buffer),
2072 0 /* no TLS */
2073 | (lflags.lmtp && ob->lmtp_ignore_quota ? PEER_OFFERED_IGNQ : 0)
2074 | PEER_OFFERED_CHUNKING
2075 | PEER_OFFERED_PRDR
2076 #ifdef SUPPORT_I18N
2077 | (addrlist->prop.utf8_msg ? PEER_OFFERED_UTF8 : 0)
2078 /*XXX if we hand peercaps on to continued-conn processes,
2079 must not depend on this addr */
2080 #endif
2081 | PEER_OFFERED_DSN
2082 | PEER_OFFERED_PIPE
2083 | (ob->size_addition >= 0 ? PEER_OFFERED_SIZE : 0)
2084 );
2085
2086 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
2087 lmtp_ignore_quota option was set. */
2088
2089 igquotstr = peer_offered & PEER_OFFERED_IGNQ ? US" IGNOREQUOTA" : US"";
2090
2091 /* If the response to EHLO specified support for the SIZE parameter, note
2092 this, provided size_addition is non-negative. */
2093
2094 smtp_peer_options |= peer_offered & PEER_OFFERED_SIZE;
2095
2096 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
2097 the current host, esmtp will be false, so PIPELINING can never be used. If
2098 the current host matches hosts_avoid_pipelining, don't do it. */
2099
2100 if ( peer_offered & PEER_OFFERED_PIPE
2101 && verify_check_given_host(&ob->hosts_avoid_pipelining, host) != OK)
2102 smtp_peer_options |= PEER_OFFERED_PIPE;
2103
2104 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
2105 smtp_peer_options & PEER_OFFERED_PIPE ? "" : "not ");
2106
2107 if ( peer_offered & PEER_OFFERED_CHUNKING
2108 && verify_check_given_host(&ob->hosts_try_chunking, host) != OK)
2109 peer_offered &= ~PEER_OFFERED_CHUNKING;
2110
2111 if (peer_offered & PEER_OFFERED_CHUNKING)
2112 {DEBUG(D_transport) debug_printf("CHUNKING usable\n");}
2113
2114 #ifndef DISABLE_PRDR
2115 if ( peer_offered & PEER_OFFERED_PRDR
2116 && verify_check_given_host(&ob->hosts_try_prdr, host) != OK)
2117 peer_offered &= ~PEER_OFFERED_PRDR;
2118
2119 if (peer_offered & PEER_OFFERED_PRDR)
2120 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
2121 #endif
2122
2123 /* Note if the server supports DSN */
2124 smtp_peer_options |= peer_offered & PEER_OFFERED_DSN;
2125 DEBUG(D_transport) debug_printf("%susing DSN\n",
2126 peer_offered & PEER_OFFERED_DSN ? "" : "not ");
2127
2128 /* Note if the response to EHLO specifies support for the AUTH extension.
2129 If it has, check that this host is one we want to authenticate to, and do
2130 the business. The host name and address must be available when the
2131 authenticator's client driver is running. */
2132
2133 switch (yield = smtp_auth(buffer, sizeof(buffer), addrlist, host,
2134 ob, lflags.esmtp, &inblock, &outblock))
2135 {
2136 default: goto SEND_QUIT;
2137 case OK: break;
2138 case FAIL_SEND: goto SEND_FAILED;
2139 case FAIL: goto RESPONSE_FAILED;
2140 }
2141 }
2142 }
2143 pipelining_active = !!(smtp_peer_options & PEER_OFFERED_PIPE);
2144
2145 /* The setting up of the SMTP call is now complete. Any subsequent errors are
2146 message-specific. */
2147
2148 lflags.setting_up = FALSE;
2149
2150 #ifdef SUPPORT_I18N
2151 if (addrlist->prop.utf8_msg)
2152 {
2153 lflags.utf8_needed = !addrlist->prop.utf8_downcvt
2154 && !addrlist->prop.utf8_downcvt_maybe;
2155 DEBUG(D_transport) if (!lflags.utf8_needed)
2156 debug_printf("utf8: %s downconvert\n",
2157 addrlist->prop.utf8_downcvt ? "mandatory" : "optional");
2158 }
2159
2160 /* If this is an international message we need the host to speak SMTPUTF8 */
2161 if (lflags.utf8_needed && !(peer_offered & PEER_OFFERED_UTF8))
2162 {
2163 errno = ERRNO_UTF8_FWD;
2164 goto RESPONSE_FAILED;
2165 }
2166 #endif
2167
2168 /* If there is a filter command specified for this transport, we can now
2169 set it up. This cannot be done until the identify of the host is known. */
2170
2171 if (tblock->filter_command != NULL)
2172 {
2173 BOOL rc;
2174 uschar buffer[64];
2175 sprintf(CS buffer, "%.50s transport", tblock->name);
2176 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
2177 TRUE, DEFER, addrlist, buffer, NULL);
2178 transport_filter_timeout = tblock->filter_timeout;
2179
2180 /* On failure, copy the error to all addresses, abandon the SMTP call, and
2181 yield ERROR. */
2182
2183 if (!rc)
2184 {
2185 set_errno_nohost(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
2186 FALSE);
2187 yield = ERROR;
2188 goto SEND_QUIT;
2189 }
2190
2191 if ( transport_filter_argv
2192 && *transport_filter_argv
2193 && **transport_filter_argv
2194 && peer_offered & PEER_OFFERED_CHUNKING
2195 )
2196 {
2197 peer_offered &= ~PEER_OFFERED_CHUNKING;
2198 DEBUG(D_transport) debug_printf("CHUNKING not usable due to transport filter\n");
2199 }
2200 }
2201
2202
2203 /* For messages that have more than the maximum number of envelope recipients,
2204 we want to send several transactions down the same SMTP connection. (See
2205 comments in deliver.c as to how this reconciles, heuristically, with
2206 remote_max_parallel.) This optimization was added to Exim after the following
2207 code was already working. The simplest way to put it in without disturbing the
2208 code was to use a goto to jump back to this point when there is another
2209 transaction to handle. */
2210
2211 SEND_MESSAGE:
2212 sync_addr = first_addr;
2213 address_count = 0;
2214 lflags.ok = FALSE;
2215 lflags.send_rset = TRUE;
2216 completed_address = FALSE;
2217
2218
2219 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
2220 qualification, send it, adding something to the message size to allow for
2221 imprecision and things that get added en route. Exim keeps the number of lines
2222 in a message, so we can give an accurate value for the original message, but we
2223 need some additional to handle added headers. (Double "." characters don't get
2224 included in the count.) */
2225
2226 p = buffer;
2227 *p = 0;
2228
2229 if (peer_offered & PEER_OFFERED_SIZE)
2230 {
2231 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
2232 while (*p) p++;
2233 }
2234
2235 #ifndef DISABLE_PRDR
2236 lflags.prdr_active = FALSE;
2237 if (peer_offered & PEER_OFFERED_PRDR)
2238 for (addr = first_addr; addr; addr = addr->next)
2239 if (addr->transport_return == PENDING_DEFER)
2240 {
2241 for (addr = addr->next; addr; addr = addr->next)
2242 if (addr->transport_return == PENDING_DEFER)
2243 { /* at least two recipients to send */
2244 lflags.prdr_active = TRUE;
2245 sprintf(CS p, " PRDR"); p += 5;
2246 break;
2247 }
2248 break;
2249 }
2250 #endif
2251
2252 #ifdef SUPPORT_I18N
2253 if ( addrlist->prop.utf8_msg
2254 && !addrlist->prop.utf8_downcvt
2255 && peer_offered & PEER_OFFERED_UTF8
2256 )
2257 sprintf(CS p, " SMTPUTF8"), p += 9;
2258 #endif
2259
2260 /* check if all addresses have lasthop flag */
2261 /* do not send RET and ENVID if true */
2262 for (lflags.dsn_all_lasthop = TRUE, addr = first_addr;
2263 address_count < max_rcpt && addr != NULL;
2264 addr = addr->next)
2265 if ((addr->dsn_flags & rf_dsnlasthop) != 1)
2266 {
2267 lflags.dsn_all_lasthop = FALSE;
2268 break;
2269 }
2270
2271 /* Add any DSN flags to the mail command */
2272
2273 if (peer_offered & PEER_OFFERED_DSN && !lflags.dsn_all_lasthop)
2274 {
2275 if (dsn_ret == dsn_ret_hdrs)
2276 { Ustrcpy(p, " RET=HDRS"); p += 9; }
2277 else if (dsn_ret == dsn_ret_full)
2278 { Ustrcpy(p, " RET=FULL"); p += 9; }
2279
2280 if (dsn_envid)
2281 {
2282 string_format(p, sizeof(buffer) - (p-buffer), " ENVID=%s", dsn_envid);
2283 while (*p) p++;
2284 }
2285 }
2286
2287 /* If an authenticated_sender override has been specified for this transport
2288 instance, expand it. If the expansion is forced to fail, and there was already
2289 an authenticated_sender for this message, the original value will be used.
2290 Other expansion failures are serious. An empty result is ignored, but there is
2291 otherwise no check - this feature is expected to be used with LMTP and other
2292 cases where non-standard addresses (e.g. without domains) might be required. */
2293
2294 if (smtp_mail_auth_str(p, sizeof(buffer) - (p-buffer), addrlist, ob))
2295 {
2296 yield = ERROR;
2297 goto SEND_QUIT;
2298 }
2299
2300 /* From here until we send the DATA command, we can make use of PIPELINING
2301 if the server host supports it. The code has to be able to check the responses
2302 at any point, for when the buffer fills up, so we write it totally generally.
2303 When PIPELINING is off, each command written reports that it has flushed the
2304 buffer. */
2305
2306 lflags.pending_MAIL = TRUE; /* The block starts with MAIL */
2307
2308 {
2309 uschar * s = return_path;
2310 #ifdef SUPPORT_I18N
2311 uschar * errstr = NULL;
2312
2313 /* If we must downconvert, do the from-address here. Remember we had to
2314 for the to-addresses (done below), and also (ugly) for re-doing when building
2315 the delivery log line. */
2316
2317 if ( addrlist->prop.utf8_msg
2318 && (addrlist->prop.utf8_downcvt || !(peer_offered & PEER_OFFERED_UTF8))
2319 )
2320 {
2321 if (s = string_address_utf8_to_alabel(return_path, &errstr), errstr)
2322 {
2323 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE);
2324 yield = ERROR;
2325 goto SEND_QUIT;
2326 }
2327 setflag(addrlist, af_utf8_downcvt);
2328 }
2329 #endif
2330
2331 rc = smtp_write_command(&outblock, pipelining_active,
2332 "MAIL FROM:<%s>%s\r\n", s, buffer);
2333 }
2334
2335 mail_command = string_copy(big_buffer); /* Save for later error message */
2336
2337 switch(rc)
2338 {
2339 case -1: /* Transmission error */
2340 goto SEND_FAILED;
2341
2342 case +1: /* Block was sent */
2343 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2344 ob->command_timeout))
2345 {
2346 if (errno == 0 && buffer[0] == '4')
2347 {
2348 errno = ERRNO_MAIL4XX;
2349 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2350 }
2351 goto RESPONSE_FAILED;
2352 }
2353 lflags.pending_MAIL = FALSE;
2354 break;
2355 }
2356
2357 /* Pass over all the relevant recipient addresses for this host, which are the
2358 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
2359 several before we have to read the responses for those seen so far. This
2360 checking is done by a subroutine because it also needs to be done at the end.
2361 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
2362 the next one if not all are sent.
2363
2364 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
2365 last address because we want to abort if any recipients have any kind of
2366 problem, temporary or permanent. We know that all recipient addresses will have
2367 the PENDING_DEFER status, because only one attempt is ever made, and we know
2368 that max_rcpt will be large, so all addresses will be done at once. */
2369
2370 for (addr = first_addr;
2371 addr && address_count < max_rcpt;
2372 addr = addr->next)
2373 if (addr->transport_return == PENDING_DEFER)
2374 {
2375 int count;
2376 BOOL no_flush;
2377 uschar * rcpt_addr;
2378
2379 addr->dsn_aware = peer_offered & PEER_OFFERED_DSN
2380 ? dsn_support_yes : dsn_support_no;
2381
2382 address_count++;
2383 no_flush = pipelining_active && (!mua_wrapper || addr->next);
2384
2385 /* Add any DSN flags to the rcpt command and add to the sent string */
2386
2387 p = buffer;
2388 *p = 0;
2389
2390 if (peer_offered & PEER_OFFERED_DSN && !(addr->dsn_flags & rf_dsnlasthop))
2391 {
2392 if (addr->dsn_flags & rf_dsnflags)
2393 {
2394 int i;
2395 BOOL first = TRUE;
2396 Ustrcpy(p, " NOTIFY=");
2397 while (*p) p++;
2398 for (i = 0; i < 4; i++)
2399 if ((addr->dsn_flags & rf_list[i]) != 0)
2400 {
2401 if (!first) *p++ = ',';
2402 first = FALSE;
2403 Ustrcpy(p, rf_names[i]);
2404 while (*p) p++;
2405 }
2406 }
2407
2408 if (addr->dsn_orcpt)
2409 {
2410 string_format(p, sizeof(buffer) - (p-buffer), " ORCPT=%s",
2411 addr->dsn_orcpt);
2412 while (*p) p++;
2413 }
2414 }
2415
2416 /* Now send the RCPT command, and process outstanding responses when
2417 necessary. After a timeout on RCPT, we just end the function, leaving the
2418 yield as OK, because this error can often mean that there is a problem with
2419 just one address, so we don't want to delay the host. */
2420
2421 rcpt_addr = transport_rcpt_address(addr, tblock->rcpt_include_affixes);
2422
2423 #ifdef SUPPORT_I18N
2424 {
2425 uschar * dummy_errstr;
2426 if ( testflag(addrlist, af_utf8_downcvt)
2427 && (rcpt_addr = string_address_utf8_to_alabel(rcpt_addr, &dummy_errstr),
2428 dummy_errstr
2429 ) )
2430 {
2431 errno = ERRNO_EXPANDFAIL;
2432 goto SEND_FAILED;
2433 }
2434 }
2435 #endif
2436
2437 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s%s\r\n",
2438 rcpt_addr, igquotstr, buffer);
2439
2440 if (count < 0) goto SEND_FAILED;
2441 if (count > 0)
2442 {
2443 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
2444 &sync_addr, host, count, ob->address_retry_include_sender,
2445 lflags.pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
2446 sizeof(buffer)))
2447 {
2448 case 3: lflags.ok = TRUE; /* 2xx & 5xx => OK & progress made */
2449 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2450 break;
2451
2452 case 1: lflags.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2453 if (!lflags.lmtp) completed_address = TRUE; /* can't tell about progress yet */
2454 case 0: /* No 2xx or 5xx, but no probs */
2455 break;
2456
2457 case -1: goto END_OFF; /* Timeout on RCPT */
2458 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
2459 }
2460 lflags.pending_MAIL = FALSE; /* Dealt with MAIL */
2461 }
2462 } /* Loop for next address */
2463
2464 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
2465 permanently or temporarily. We should have flushed and synced after the last
2466 RCPT. */
2467
2468 if (mua_wrapper)
2469 {
2470 address_item *badaddr;
2471 for (badaddr = first_addr; badaddr; badaddr = badaddr->next)
2472 if (badaddr->transport_return != PENDING_OK)
2473 {
2474 /*XXX could we find a better errno than 0 here? */
2475 set_errno_nohost(addrlist, 0, badaddr->message, FAIL,
2476 testflag(badaddr, af_pass_message));
2477 lflags.ok = FALSE;
2478 break;
2479 }
2480 }
2481
2482 /* If ok is TRUE, we know we have got at least one good recipient, and must now
2483 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
2484 have a good recipient buffered up if we are pipelining. We don't want to waste
2485 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
2486 are pipelining. The responses are all handled by sync_responses().
2487 If using CHUNKING, do not send a BDAT until we know how big a chunk we want
2488 to send is. */
2489
2490 if ( !(peer_offered & PEER_OFFERED_CHUNKING)
2491 && (lflags.ok || (pipelining_active && !mua_wrapper)))
2492 {
2493 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
2494
2495 if (count < 0) goto SEND_FAILED;
2496 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
2497 host, count, ob->address_retry_include_sender, lflags.pending_MAIL,
2498 lflags.ok ? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
2499 {
2500 case 3: lflags.ok = TRUE; /* 2xx & 5xx => OK & progress made */
2501 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2502 break;
2503
2504 case 1: lflags.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2505 if (!lflags.lmtp) completed_address = TRUE; /* can't tell about progress yet */
2506 case 0: break; /* No 2xx or 5xx, but no probs */
2507
2508 case -1: goto END_OFF; /* Timeout on RCPT */
2509 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2510 }
2511 pipelining_active = FALSE;
2512 }
2513
2514 /* If there were no good recipients (but otherwise there have been no
2515 problems), just set ok TRUE, since we have handled address-specific errors
2516 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
2517 for handling the SMTP dot-handling protocol, flagging to apply to headers as
2518 well as body. Set the appropriate timeout value to be used for each chunk.
2519 (Haven't been able to make it work using select() for writing yet.) */
2520
2521 if (!(peer_offered & PEER_OFFERED_CHUNKING) && !lflags.ok)
2522 {
2523 /* Save the first address of the next batch. */
2524 first_addr = addr;
2525
2526 lflags.ok = TRUE;
2527 }
2528 else
2529 {
2530 transport_ctx tctx = {
2531 tblock,
2532 addrlist,
2533 US".", US"..", /* Escaping strings */
2534 topt_use_crlf | topt_escape_headers
2535 | (tblock->body_only ? topt_no_headers : 0)
2536 | (tblock->headers_only ? topt_no_body : 0)
2537 | (tblock->return_path_add ? topt_add_return_path : 0)
2538 | (tblock->delivery_date_add ? topt_add_delivery_date : 0)
2539 | (tblock->envelope_to_add ? topt_add_envelope_to : 0)
2540 };
2541
2542 /* If using CHUNKING we need a callback from the generic transport
2543 support to us, for the sending of BDAT smtp commands and the reaping
2544 of responses. The callback needs a whole bunch of state so set up
2545 a transport-context structure to be passed around. */
2546
2547 if (peer_offered & PEER_OFFERED_CHUNKING)
2548 {
2549 tctx.check_string = tctx.escape_string = NULL;
2550 tctx.options |= topt_use_bdat;
2551 tctx.chunk_cb = smtp_chunk_cmd_callback;
2552 tctx.inblock = &inblock;
2553 tctx.outblock = &outblock;
2554 tctx.host = host;
2555 tctx.first_addr = first_addr;
2556 tctx.sync_addr = &sync_addr;
2557 tctx.pending_MAIL = lflags.pending_MAIL;
2558 tctx.pending_BDAT = FALSE;
2559 tctx.good_RCPT = lflags.ok;
2560 tctx.completed_address = &completed_address;
2561 tctx.cmd_count = 0;
2562 tctx.buffer = buffer;
2563 }
2564 else
2565 tctx.options |= topt_end_dot;
2566
2567 /* Save the first address of the next batch. */
2568 first_addr = addr;
2569
2570 /* Responses from CHUNKING commands go in buffer. Otherwise,
2571 there has not been a response. */
2572
2573 buffer[0] = 0;
2574
2575 sigalrm_seen = FALSE;
2576 transport_write_timeout = ob->data_timeout;
2577 smtp_command = US"sending data block"; /* For error messages */
2578 DEBUG(D_transport|D_v)
2579 if (peer_offered & PEER_OFFERED_CHUNKING)
2580 debug_printf(" will write message using CHUNKING\n");
2581 else
2582 debug_printf(" SMTP>> writing message and terminating \".\"\n");
2583 transport_count = 0;
2584
2585 #ifndef DISABLE_DKIM
2586 lflags.ok = dkim_transport_write_message(inblock.sock, &tctx, &ob->dkim);
2587 #else
2588 lflags.ok = transport_write_message(inblock.sock, &tctx, 0);
2589 #endif
2590
2591 /* transport_write_message() uses write() because it is called from other
2592 places to write to non-sockets. This means that under some OS (e.g. Solaris)
2593 it can exit with "Broken pipe" as its error. This really means that the
2594 socket got closed at the far end. */
2595
2596 transport_write_timeout = 0; /* for subsequent transports */
2597
2598 /* Failure can either be some kind of I/O disaster (including timeout),
2599 or the failure of a transport filter or the expansion of added headers.
2600 Or, when CHUNKING, it can be a protocol-detected failure. */
2601
2602 if (!lflags.ok)
2603 goto RESPONSE_FAILED;
2604
2605 /* We used to send the terminating "." explicitly here, but because of
2606 buffering effects at both ends of TCP/IP connections, you don't gain
2607 anything by keeping it separate, so it might as well go in the final
2608 data buffer for efficiency. This is now done by setting the topt_end_dot
2609 flag above. */
2610
2611 smtp_command = US"end of data";
2612
2613 if (peer_offered & PEER_OFFERED_CHUNKING && tctx.cmd_count > 1)
2614 {
2615 /* Reap any outstanding MAIL & RCPT commands, but not a DATA-go-ahead */
2616 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
2617 host, tctx.cmd_count-1, ob->address_retry_include_sender,
2618 lflags.pending_MAIL, 0,
2619 &inblock, ob->command_timeout, buffer, sizeof(buffer)))
2620 {
2621 case 3: lflags.ok = TRUE; /* 2xx & 5xx => OK & progress made */
2622 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2623 break;
2624
2625 case 1: lflags.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2626 if (!lflags.lmtp) completed_address = TRUE; /* can't tell about progress yet */
2627 case 0: break; /* No 2xx or 5xx, but no probs */
2628
2629 case -1: goto END_OFF; /* Timeout on RCPT */
2630 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2631 }
2632 }
2633
2634 #ifndef DISABLE_PRDR
2635 /* For PRDR we optionally get a partial-responses warning
2636 * followed by the individual responses, before going on with
2637 * the overall response. If we don't get the warning then deal
2638 * with per non-PRDR. */
2639 if(lflags.prdr_active)
2640 {
2641 lflags.ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '3',
2642 ob->final_timeout);
2643 if (!lflags.ok && errno == 0) switch(buffer[0])
2644 {
2645 case '2': lflags.prdr_active = FALSE;
2646 lflags.ok = TRUE;
2647 break;
2648 case '4': errno = ERRNO_DATA4XX;
2649 addrlist->more_errno |=
2650 ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2651 break;
2652 }
2653 }
2654 else
2655 #endif
2656
2657 /* For non-PRDR SMTP, we now read a single response that applies to the
2658 whole message. If it is OK, then all the addresses have been delivered. */
2659
2660 if (!lflags.lmtp)
2661 {
2662 lflags.ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2663 ob->final_timeout);
2664 if (!lflags.ok && errno == 0 && buffer[0] == '4')
2665 {
2666 errno = ERRNO_DATA4XX;
2667 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2668 }
2669 }
2670
2671 /* For LMTP, we get back a response for every RCPT command that we sent;
2672 some may be accepted and some rejected. For those that get a response, their
2673 status is fixed; any that are accepted have been handed over, even if later
2674 responses crash - at least, that's how I read RFC 2033.
2675
2676 If all went well, mark the recipient addresses as completed, record which
2677 host/IPaddress they were delivered to, and cut out RSET when sending another
2678 message down the same channel. Write the completed addresses to the journal
2679 now so that they are recorded in case there is a crash of hardware or
2680 software before the spool gets updated. Also record the final SMTP
2681 confirmation if needed (for SMTP only). */
2682
2683 if (lflags.ok)
2684 {
2685 int flag = '=';
2686 int delivery_time = (int)(time(NULL) - start_delivery_time);
2687 int len;
2688 uschar *conf = NULL;
2689
2690 lflags.send_rset = FALSE;
2691 pipelining_active = FALSE;
2692
2693 /* Set up confirmation if needed - applies only to SMTP */
2694
2695 if (
2696 #ifdef DISABLE_EVENT
2697 LOGGING(smtp_confirmation) &&
2698 #endif
2699 !lflags.lmtp
2700 )
2701 {
2702 const uschar *s = string_printing(buffer);
2703 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
2704 conf = (s == buffer)? (uschar *)string_copy(s) : US s;
2705 }
2706
2707 /* Process all transported addresses - for LMTP or PRDR, read a status for
2708 each one. */
2709
2710 for (addr = addrlist; addr != first_addr; addr = addr->next)
2711 {
2712 if (addr->transport_return != PENDING_OK) continue;
2713
2714 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
2715 remaining addresses. Otherwise, it's a return code for just the one
2716 address. For temporary errors, add a retry item for the address so that
2717 it doesn't get tried again too soon. */
2718
2719 #ifndef DISABLE_PRDR
2720 if (lflags.lmtp || lflags.prdr_active)
2721 #else
2722 if (lflags.lmtp)
2723 #endif
2724 {
2725 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2726 ob->final_timeout))
2727 {
2728 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
2729 addr->message = string_sprintf(
2730 #ifndef DISABLE_PRDR
2731 "%s error after %s: %s", lflags.prdr_active ? "PRDR":"LMTP",
2732 #else
2733 "LMTP error after %s: %s",
2734 #endif
2735 big_buffer, string_printing(buffer));
2736 setflag(addr, af_pass_message); /* Allow message to go to user */
2737 if (buffer[0] == '5')
2738 addr->transport_return = FAIL;
2739 else
2740 {
2741 errno = ERRNO_DATA4XX;
2742 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2743 addr->transport_return = DEFER;
2744 #ifndef DISABLE_PRDR
2745 if (!lflags.prdr_active)
2746 #endif
2747 retry_add_item(addr, addr->address_retry_key, 0);
2748 }
2749 continue;
2750 }
2751 completed_address = TRUE; /* NOW we can set this flag */
2752 if (LOGGING(smtp_confirmation))
2753 {
2754 const uschar *s = string_printing(buffer);
2755 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
2756 conf = (s == buffer)? (uschar *)string_copy(s) : US s;
2757 }
2758 }
2759
2760 /* SMTP, or success return from LMTP for this address. Pass back the
2761 actual host that was used. */
2762
2763 addr->transport_return = OK;
2764 addr->more_errno = delivery_time;
2765 addr->host_used = host;
2766 addr->special_action = flag;
2767 addr->message = conf;
2768 #ifndef DISABLE_PRDR
2769 if (lflags.prdr_active) addr->flags |= af_prdr_used;
2770 #endif
2771 if (peer_offered & PEER_OFFERED_CHUNKING) addr->flags |= af_chunking_used;
2772 flag = '-';
2773
2774 #ifndef DISABLE_PRDR
2775 if (!lflags.prdr_active)
2776 #endif
2777 {
2778 /* Update the journal. For homonymic addresses, use the base address plus
2779 the transport name. See lots of comments in deliver.c about the reasons
2780 for the complications when homonyms are involved. Just carry on after
2781 write error, as it may prove possible to update the spool file later. */
2782
2783 if (testflag(addr, af_homonym))
2784 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2785 else
2786 sprintf(CS buffer, "%.500s\n", addr->unique);
2787
2788 DEBUG(D_deliver) debug_printf("journalling %s\n", buffer);
2789 len = Ustrlen(CS buffer);
2790 if (write(journal_fd, buffer, len) != len)
2791 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2792 "%s: %s", buffer, strerror(errno));
2793 }
2794 }
2795
2796 #ifndef DISABLE_PRDR
2797 if (lflags.prdr_active)
2798 {
2799 /* PRDR - get the final, overall response. For any non-success
2800 upgrade all the address statuses. */
2801 lflags.ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2802 ob->final_timeout);
2803 if (!lflags.ok)
2804 {
2805 if(errno == 0 && buffer[0] == '4')
2806 {
2807 errno = ERRNO_DATA4XX;
2808 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2809 }
2810 for (addr = addrlist; addr != first_addr; addr = addr->next)
2811 if (buffer[0] == '5' || addr->transport_return == OK)
2812 addr->transport_return = PENDING_OK; /* allow set_errno action */
2813 goto RESPONSE_FAILED;
2814 }
2815
2816 /* Update the journal, or setup retry. */
2817 for (addr = addrlist; addr != first_addr; addr = addr->next)
2818 if (addr->transport_return == OK)
2819 {
2820 if (testflag(addr, af_homonym))
2821 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2822 else
2823 sprintf(CS buffer, "%.500s\n", addr->unique);
2824
2825 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s\n", buffer);
2826 len = Ustrlen(CS buffer);
2827 if (write(journal_fd, buffer, len) != len)
2828 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2829 "%s: %s", buffer, strerror(errno));
2830 }
2831 else if (addr->transport_return == DEFER)
2832 retry_add_item(addr, addr->address_retry_key, -2);
2833 }
2834 #endif
2835
2836 /* Ensure the journal file is pushed out to disk. */
2837
2838 if (EXIMfsync(journal_fd) < 0)
2839 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
2840 strerror(errno));
2841 }
2842 }
2843
2844
2845 /* Handle general (not specific to one address) failures here. The value of ok
2846 is used to skip over this code on the falling through case. A timeout causes a
2847 deferral. Other errors may defer or fail according to the response code, and
2848 may set up a special errno value, e.g. after connection chopped, which is
2849 assumed if errno == 0 and there is no text in the buffer. If control reaches
2850 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
2851 the problem is not related to this specific message. */
2852
2853 if (!lflags.ok)
2854 {
2855 int code, set_rc;
2856 uschar * set_message;
2857
2858 RESPONSE_FAILED:
2859 {
2860 save_errno = errno;
2861 message = NULL;
2862 lflags.send_quit = check_response(host, &save_errno, addrlist->more_errno,
2863 buffer, &code, &message, &pass_message);
2864 goto FAILED;
2865 }
2866
2867 SEND_FAILED:
2868 {
2869 save_errno = errno;
2870 code = '4';
2871 message = US string_sprintf("send() to %s [%s] failed: %s",
2872 host->name, host->address, strerror(save_errno));
2873 lflags.send_quit = FALSE;
2874 goto FAILED;
2875 }
2876
2877 /* This label is jumped to directly when a TLS negotiation has failed,
2878 or was not done for a host for which it is required. Values will be set
2879 in message and save_errno, and setting_up will always be true. Treat as
2880 a temporary error. */
2881
2882 #ifdef SUPPORT_TLS
2883 TLS_FAILED:
2884 code = '4';
2885 #endif
2886
2887 /* If the failure happened while setting up the call, see if the failure was
2888 a 5xx response (this will either be on connection, or following HELO - a 5xx
2889 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
2890 never going to accept them. For other errors during setting up (timeouts or
2891 whatever), defer all addresses, and yield DEFER, so that the host is not
2892 tried again for a while. */
2893
2894 FAILED:
2895 lflags.ok = FALSE; /* For when reached by GOTO */
2896 set_message = message;
2897
2898 if (lflags.setting_up)
2899 if (code == '5')
2900 set_rc = FAIL;
2901 else
2902 yield = set_rc = DEFER;
2903
2904 /* We want to handle timeouts after MAIL or "." and loss of connection after
2905 "." specially. They can indicate a problem with the sender address or with
2906 the contents of the message rather than a real error on the connection. These
2907 cases are treated in the same way as a 4xx response. This next bit of code
2908 does the classification. */
2909
2910 else
2911 {
2912 BOOL message_error;
2913
2914 switch(save_errno)
2915 {
2916 #ifdef SUPPORT_I18N
2917 case ERRNO_UTF8_FWD:
2918 code = '5';
2919 /*FALLTHROUGH*/
2920 #endif
2921 case 0:
2922 case ERRNO_MAIL4XX:
2923 case ERRNO_DATA4XX:
2924 message_error = TRUE;
2925 break;
2926
2927 case ETIMEDOUT:
2928 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
2929 Ustrncmp(smtp_command,"end ",4) == 0;
2930 break;
2931
2932 case ERRNO_SMTPCLOSED:
2933 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
2934 break;
2935
2936 default:
2937 message_error = FALSE;
2938 break;
2939 }
2940
2941 /* Handle the cases that are treated as message errors. These are:
2942
2943 (a) negative response or timeout after MAIL
2944 (b) negative response after DATA
2945 (c) negative response or timeout or dropped connection after "."
2946 (d) utf8 support required and not offered
2947
2948 It won't be a negative response or timeout after RCPT, as that is dealt
2949 with separately above. The action in all cases is to set an appropriate
2950 error code for all the addresses, but to leave yield set to OK because the
2951 host itself has not failed. Of course, it might in practice have failed
2952 when we've had a timeout, but if so, we'll discover that at the next
2953 delivery attempt. For a temporary error, set the message_defer flag, and
2954 write to the logs for information if this is not the last host. The error
2955 for the last host will be logged as part of the address's log line. */
2956
2957 if (message_error)
2958 {
2959 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
2960
2961 /* If there's an errno, the message contains just the identity of
2962 the host. */
2963
2964 if (code == '5')
2965 set_rc = FAIL;
2966 else /* Anything other than 5 is treated as temporary */
2967 {
2968 set_rc = DEFER;
2969 if (save_errno > 0)
2970 message = US string_sprintf("%s: %s", message, strerror(save_errno));
2971 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
2972 msglog_line(host, message);
2973 *message_defer = TRUE;
2974 }
2975 }
2976
2977 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
2978 ".", or some other transportation error. We defer all addresses and yield
2979 DEFER, except for the case of failed add_headers expansion, or a transport
2980 filter failure, when the yield should be ERROR, to stop it trying other
2981 hosts. */
2982
2983 else
2984 {
2985 set_rc = DEFER;
2986 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
2987 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
2988 }
2989 }
2990
2991 set_errno(addrlist, save_errno, set_message, set_rc, pass_message, host
2992 #ifdef EXPERIMENTAL_DSN_INFO
2993 , smtp_greeting, helo_response
2994 #endif
2995 );
2996 }
2997
2998
2999 /* If all has gone well, send_quit will be set TRUE, implying we can end the
3000 SMTP session tidily. However, if there were too many addresses to send in one
3001 message (indicated by first_addr being non-NULL) we want to carry on with the
3002 rest of them. Also, it is desirable to send more than one message down the SMTP
3003 connection if there are several waiting, provided we haven't already sent so
3004 many as to hit the configured limit. The function transport_check_waiting looks
3005 for a waiting message and returns its id. Then transport_pass_socket tries to
3006 set up a continued delivery by passing the socket on to another process. The
3007 variable send_rset is FALSE if a message has just been successfully transfered.
3008
3009 If we are already sending down a continued channel, there may be further
3010 addresses not yet delivered that are aimed at the same host, but which have not
3011 been passed in this run of the transport. In this case, continue_more will be
3012 true, and all we should do is send RSET if necessary, and return, leaving the
3013 channel open.
3014
3015 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
3016 do not want to continue with other messages down the same channel, because that
3017 can lead to looping between two or more messages, all with the same,
3018 temporarily failing address(es). [The retry information isn't updated yet, so
3019 new processes keep on trying.] We probably also don't want to try more of this
3020 message's addresses either.
3021
3022 If we have started a TLS session, we have to end it before passing the
3023 connection to a new process. However, not all servers can handle this (Exim
3024 can), so we do not pass such a connection on if the host matches
3025 hosts_nopass_tls. */
3026
3027 DEBUG(D_transport)
3028 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
3029 "yield=%d first_address is %sNULL\n", lflags.ok, lflags.send_quit,
3030 lflags.send_rset, continue_more, yield, first_addr ? "not " : "");
3031
3032 if (completed_address && lflags.ok && lflags.send_quit)
3033 {
3034 BOOL more;
3035 smtp_compare_t t_compare;
3036
3037 t_compare.tblock = tblock;
3038 t_compare.current_sender_address = sender_address;
3039
3040 if ( first_addr != NULL
3041 || continue_more
3042 || ( ( tls_out.active < 0
3043 || verify_check_given_host(&ob->hosts_nopass_tls, host) != OK
3044 )
3045 &&
3046 transport_check_waiting(tblock->name, host->name,
3047 tblock->connection_max_messages, new_message_id, &more,
3048 (oicf)smtp_are_same_identities, (void*)&t_compare)
3049 ) )
3050 {
3051 uschar *msg;
3052 BOOL pass_message;
3053
3054 if (lflags.send_rset)
3055 {
3056 if (! (lflags.ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
3057 {
3058 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
3059 host->address, strerror(save_errno));
3060 lflags.send_quit = FALSE;
3061 }
3062 else if (! (lflags.ok = smtp_read_response(&inblock, buffer,
3063 sizeof(buffer), '2', ob->command_timeout)))
3064 {
3065 int code;
3066 lflags.send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
3067 &pass_message);
3068 if (!lflags.send_quit)
3069 {
3070 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
3071 host->name, host->address, msg);
3072 }
3073 }
3074 }
3075
3076 /* Either RSET was not needed, or it succeeded */
3077
3078 if (lflags.ok)
3079 {
3080 if (first_addr != NULL) /* More addresses still to be sent */
3081 { /* in this run of the transport */
3082 continue_sequence++; /* Causes * in logging */
3083 goto SEND_MESSAGE;
3084 }
3085 if (continue_more) return yield; /* More addresses for another run */
3086
3087 /* Pass the socket to a new Exim process. Before doing so, we must shut
3088 down TLS. Not all MTAs allow for the continuation of the SMTP session
3089 when TLS is shut down. We test for this by sending a new EHLO. If we
3090 don't get a good response, we don't attempt to pass the socket on. */
3091
3092 #ifdef SUPPORT_TLS
3093 if (tls_out.active >= 0)
3094 {
3095 tls_close(FALSE, TRUE);
3096 smtp_peer_options = smtp_peer_options_wrap;
3097 if (lflags.smtps)
3098 lflags.ok = FALSE;
3099 else
3100 lflags.ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
3101 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
3102 ob->command_timeout);
3103 }
3104 #endif
3105
3106 /* If the socket is successfully passed, we musn't send QUIT (or
3107 indeed anything!) from here. */
3108
3109 /*XXX DSN_INFO: assume likely to do new HELO; but for greet we'll want to
3110 propagate it from the initial
3111 */
3112 if (lflags.ok && transport_pass_socket(tblock->name, host->name,
3113 host->address, new_message_id, inblock.sock))
3114 lflags.send_quit = FALSE;
3115 }
3116
3117 /* If RSET failed and there are addresses left, they get deferred. */
3118
3119 else set_errno(first_addr, errno, msg, DEFER, FALSE, host
3120 #ifdef EXPERIMENTAL_DSN_INFO
3121 , smtp_greeting, helo_response
3122 #endif
3123 );
3124 }
3125 }
3126
3127 /* End off tidily with QUIT unless the connection has died or the socket has
3128 been passed to another process. There has been discussion on the net about what
3129 to do after sending QUIT. The wording of the RFC suggests that it is necessary
3130 to wait for a response, but on the other hand, there isn't anything one can do
3131 with an error response, other than log it. Exim used to do that. However,
3132 further discussion suggested that it is positively advantageous not to wait for
3133 the response, but to close the session immediately. This is supposed to move
3134 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
3135 load from the server. (Hosts that are both servers and clients may not see much
3136 difference, of course.) Further discussion indicated that this was safe to do
3137 on Unix systems which have decent implementations of TCP/IP that leave the
3138 connection around for a while (TIME_WAIT) after the application has gone away.
3139 This enables the response sent by the server to be properly ACKed rather than
3140 timed out, as can happen on broken TCP/IP implementations on other OS.
3141
3142 This change is being made on 31-Jul-98. After over a year of trouble-free
3143 operation, the old commented-out code was removed on 17-Sep-99. */
3144
3145 SEND_QUIT:
3146 if (lflags.send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
3147
3148 END_OFF:
3149
3150 #ifdef SUPPORT_TLS
3151 tls_close(FALSE, TRUE);
3152 #endif
3153
3154 /* Close the socket, and return the appropriate value, first setting
3155 works because the NULL setting is passed back to the calling process, and
3156 remote_max_parallel is forced to 1 when delivering over an existing connection,
3157
3158 If all went well and continue_more is set, we shouldn't actually get here if
3159 there are further addresses, as the return above will be taken. However,
3160 writing RSET might have failed, or there may be other addresses whose hosts are
3161 specified in the transports, and therefore not visible at top level, in which
3162 case continue_more won't get set. */
3163
3164 HDEBUG(D_transport|D_acl|D_v) debug_printf(" SMTP(close)>>\n");
3165 if (lflags.send_quit)
3166 {
3167 shutdown(outblock.sock, SHUT_WR);
3168 for (rc = 16; read(inblock.sock, inbuffer, sizeof(inbuffer)) > 0 && rc > 0;)
3169 rc--; /* drain socket */
3170 }
3171 (void)close(inblock.sock);
3172
3173 #ifndef DISABLE_EVENT
3174 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
3175 #endif
3176
3177 continue_transport = NULL;
3178 continue_hostname = NULL;
3179 return yield;
3180 }
3181
3182
3183
3184
3185 /*************************************************
3186 * Closedown entry point *
3187 *************************************************/
3188
3189 /* This function is called when exim is passed an open smtp channel
3190 from another incarnation, but the message which it has been asked
3191 to deliver no longer exists. The channel is on stdin.
3192
3193 We might do fancy things like looking for another message to send down
3194 the channel, but if the one we sought has gone, it has probably been
3195 delivered by some other process that itself will seek further messages,
3196 so just close down our connection.
3197
3198 Argument: pointer to the transport instance block
3199 Returns: nothing
3200 */
3201
3202 void
3203 smtp_transport_closedown(transport_instance *tblock)
3204 {
3205 smtp_transport_options_block *ob =
3206 (smtp_transport_options_block *)(tblock->options_block);
3207 smtp_inblock inblock;
3208 smtp_outblock outblock;
3209 uschar buffer[256];
3210 uschar inbuffer[4096];
3211 uschar outbuffer[16];
3212
3213 inblock.sock = fileno(stdin);
3214 inblock.buffer = inbuffer;
3215 inblock.buffersize = sizeof(inbuffer);
3216 inblock.ptr = inbuffer;
3217 inblock.ptrend = inbuffer;
3218
3219 outblock.sock = inblock.sock;
3220 outblock.buffersize = sizeof(outbuffer);
3221 outblock.buffer = outbuffer;
3222 outblock.ptr = outbuffer;
3223 outblock.cmd_count = 0;
3224 outblock.authenticating = FALSE;
3225
3226 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
3227 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
3228 ob->command_timeout);
3229 (void)close(inblock.sock);
3230 }
3231
3232
3233
3234 /*************************************************
3235 * Prepare addresses for delivery *
3236 *************************************************/
3237
3238 /* This function is called to flush out error settings from previous delivery
3239 attempts to other hosts. It also records whether we got here via an MX record
3240 or not in the more_errno field of the address. We are interested only in
3241 addresses that are still marked DEFER - others may have got delivered to a
3242 previously considered IP address. Set their status to PENDING_DEFER to indicate
3243 which ones are relevant this time.
3244
3245 Arguments:
3246 addrlist the list of addresses
3247 host the host we are delivering to
3248
3249 Returns: the first address for this delivery
3250 */
3251
3252 static address_item *
3253 prepare_addresses(address_item *addrlist, host_item *host)
3254 {
3255 address_item *first_addr = NULL;
3256 address_item *addr;
3257 for (addr = addrlist; addr; addr = addr->next)
3258 if (addr->transport_return == DEFER)
3259 {
3260 if (!first_addr) first_addr = addr;
3261 addr->transport_return = PENDING_DEFER;
3262 addr->basic_errno = 0;
3263 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
3264 addr->message = NULL;
3265 #ifdef SUPPORT_TLS
3266 addr->cipher = NULL;
3267 addr->ourcert = NULL;
3268 addr->peercert = NULL;
3269 addr->peerdn = NULL;
3270 addr->ocsp = OCSP_NOT_REQ;
3271 #endif
3272 #ifdef EXPERIMENTAL_DSN_INFO
3273 addr->smtp_greeting = NULL;
3274 addr->helo_response = NULL;
3275 #endif
3276 }
3277 return first_addr;
3278 }
3279
3280
3281
3282 /*************************************************
3283 * Main entry point *
3284 *************************************************/
3285
3286 /* See local README for interface details. As this is a remote transport, it is
3287 given a chain of addresses to be delivered in one connection, if possible. It
3288 always returns TRUE, indicating that each address has its own independent
3289 status set, except if there is a setting up problem, in which case it returns
3290 FALSE. */
3291
3292 BOOL
3293 smtp_transport_entry(
3294 transport_instance *tblock, /* data for this instantiation */
3295 address_item *addrlist) /* addresses we are working on */
3296 {
3297 int cutoff_retry;
3298 int port;
3299 int hosts_defer = 0;
3300 int hosts_fail = 0;
3301 int hosts_looked_up = 0;
3302 int hosts_retry = 0;
3303 int hosts_serial = 0;
3304 int hosts_total = 0;
3305 int total_hosts_tried = 0;
3306 address_item *addr;
3307 BOOL expired = TRUE;
3308 uschar *expanded_hosts = NULL;
3309 uschar *pistring;
3310 uschar *tid = string_sprintf("%s transport", tblock->name);
3311 smtp_transport_options_block *ob =
3312 (smtp_transport_options_block *)(tblock->options_block);
3313 host_item *hostlist = addrlist->host_list;
3314 host_item *host = NULL;
3315
3316 DEBUG(D_transport)
3317 {
3318 debug_printf("%s transport entered\n", tblock->name);
3319 for (addr = addrlist; addr; addr = addr->next)
3320 debug_printf(" %s\n", addr->address);
3321 if (hostlist)
3322 {
3323 debug_printf("hostlist:\n");
3324 for (host = hostlist; host; host = host->next)
3325 debug_printf(" %s:%d\n", host->name, host->port);
3326 }
3327 if (continue_hostname) debug_printf("already connected to %s [%s]\n",
3328 continue_hostname, continue_host_address);
3329 }
3330
3331 /* Set the flag requesting that these hosts be added to the waiting
3332 database if the delivery fails temporarily or if we are running with
3333 queue_smtp or a 2-stage queue run. This gets unset for certain
3334 kinds of error, typically those that are specific to the message. */
3335
3336 update_waiting = TRUE;
3337
3338 /* If a host list is not defined for the addresses - they must all have the
3339 same one in order to be passed to a single transport - or if the transport has
3340 a host list with hosts_override set, use the host list supplied with the
3341 transport. It is an error for this not to exist. */
3342
3343 if (!hostlist || (ob->hosts_override && ob->hosts))
3344 {
3345 if (!ob->hosts)
3346 {
3347 addrlist->message = string_sprintf("%s transport called with no hosts set",
3348 tblock->name);
3349 addrlist->transport_return = PANIC;
3350 return FALSE; /* Only top address has status */
3351 }
3352
3353 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
3354 ob->hosts);
3355
3356 /* If the transport's host list contains no '$' characters, and we are not
3357 randomizing, it is fixed and therefore a chain of hosts can be built once
3358 and for all, and remembered for subsequent use by other calls to this
3359 transport. If, on the other hand, the host list does contain '$', or we are
3360 randomizing its order, we have to rebuild it each time. In the fixed case,
3361 as the hosts string will never be used again, it doesn't matter that we
3362 replace all the : characters with zeros. */
3363
3364 if (!ob->hostlist)
3365 {
3366 uschar *s = ob->hosts;
3367
3368 if (Ustrchr(s, '$') != NULL)
3369 {
3370 if (!(expanded_hosts = expand_string(s)))
3371 {
3372 addrlist->message = string_sprintf("failed to expand list of hosts "
3373 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
3374 addrlist->transport_return = search_find_defer ? DEFER : PANIC;
3375 return FALSE; /* Only top address has status */
3376 }
3377 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
3378 "\"%s\"\n", s, expanded_hosts);
3379 s = expanded_hosts;
3380 }
3381 else
3382 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
3383
3384 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
3385
3386 /* Check that the expansion yielded something useful. */
3387 if (!hostlist)
3388 {
3389 addrlist->message =
3390 string_sprintf("%s transport has empty hosts setting", tblock->name);
3391 addrlist->transport_return = PANIC;
3392 return FALSE; /* Only top address has status */
3393 }
3394
3395 /* If there was no expansion of hosts, save the host list for
3396 next time. */
3397
3398 if (!expanded_hosts) ob->hostlist = hostlist;
3399 }
3400
3401 /* This is not the first time this transport has been run in this delivery;
3402 the host list was built previously. */
3403
3404 else
3405 hostlist = ob->hostlist;
3406 }
3407
3408 /* The host list was supplied with the address. If hosts_randomize is set, we
3409 must sort it into a random order if it did not come from MX records and has not
3410 already been randomized (but don't bother if continuing down an existing
3411 connection). */
3412
3413 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continue_hostname)
3414 {
3415 host_item *newlist = NULL;
3416 while (hostlist)
3417 {
3418 host_item *h = hostlist;
3419 hostlist = hostlist->next;
3420
3421 h->sort_key = random_number(100);
3422
3423 if (!newlist)
3424 {
3425 h->next = NULL;
3426 newlist = h;
3427 }
3428 else if (h->sort_key < newlist->sort_key)
3429 {
3430 h->next = newlist;
3431 newlist = h;
3432 }
3433 else
3434 {
3435 host_item *hh = newlist;
3436 while (hh->next)
3437 {
3438 if (h->sort_key < hh->next->sort_key) break;
3439 hh = hh->next;
3440 }
3441 h->next = hh->next;
3442 hh->next = h;
3443 }
3444 }
3445
3446 hostlist = addrlist->host_list = newlist;
3447 }
3448
3449 /* Sort out the default port. */
3450
3451 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
3452
3453 /* For each host-plus-IP-address on the list:
3454
3455 . If this is a continued delivery and the host isn't the one with the
3456 current connection, skip.
3457
3458 . If the status is unusable (i.e. previously failed or retry checked), skip.
3459
3460 . If no IP address set, get the address, either by turning the name into
3461 an address, calling gethostbyname if gethostbyname is on, or by calling
3462 the DNS. The DNS may yield multiple addresses, in which case insert the
3463 extra ones into the list.
3464
3465 . Get the retry data if not previously obtained for this address and set the
3466 field which remembers the state of this address. Skip if the retry time is
3467 not reached. If not, remember whether retry data was found. The retry string
3468 contains both the name and the IP address.
3469
3470 . Scan the list of addresses and mark those whose status is DEFER as
3471 PENDING_DEFER. These are the only ones that will be processed in this cycle
3472 of the hosts loop.
3473
3474 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
3475 Some addresses may be successfully delivered, others may fail, and yet
3476 others may get temporary errors and so get marked DEFER.
3477
3478 . The return from the delivery attempt is OK if a connection was made and a
3479 valid SMTP dialogue was completed. Otherwise it is DEFER.
3480
3481 . If OK, add a "remove" retry item for this host/IPaddress, if any.
3482
3483 . If fail to connect, or other defer state, add a retry item.
3484
3485 . If there are any addresses whose status is still DEFER, carry on to the
3486 next host/IPaddress, unless we have tried the number of hosts given
3487 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
3488 there is some fancy logic for hosts_max_try that means its limit can be
3489 overstepped in some circumstances.
3490
3491 If we get to the end of the list, all hosts have deferred at least one address,
3492 or not reached their retry times. If delay_after_cutoff is unset, it requests a
3493 delivery attempt to those hosts whose last try was before the arrival time of
3494 the current message. To cope with this, we have to go round the loop a second
3495 time. After that, set the status and error data for any addresses that haven't
3496 had it set already. */
3497
3498 for (cutoff_retry = 0;
3499 expired && cutoff_retry < (ob->delay_after_cutoff ? 1 : 2);
3500 cutoff_retry++)
3501 {
3502 host_item *nexthost = NULL;
3503 int unexpired_hosts_tried = 0;
3504
3505 for (host = hostlist;
3506 host
3507 && unexpired_hosts_tried < ob->hosts_max_try
3508 && total_hosts_tried < ob->hosts_max_try_hardlimit;
3509 host = nexthost)
3510 {
3511 int rc;
3512 int host_af;
3513 uschar *rs;
3514 BOOL host_is_expired = FALSE;
3515 BOOL message_defer = FALSE;
3516 BOOL some_deferred = FALSE;
3517 address_item *first_addr = NULL;
3518 uschar *interface = NULL;
3519 uschar *retry_host_key = NULL;
3520 uschar *retry_message_key = NULL;
3521 uschar *serialize_key = NULL;
3522
3523 /* Default next host is next host. :-) But this can vary if the
3524 hosts_max_try limit is hit (see below). It may also be reset if a host
3525 address is looked up here (in case the host was multihomed). */
3526
3527 nexthost = host->next;
3528
3529 /* If the address hasn't yet been obtained from the host name, look it up
3530 now, unless the host is already marked as unusable. If it is marked as
3531 unusable, it means that the router was unable to find its IP address (in
3532 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
3533 the lookup failed last time. We don't get this far if *all* MX records
3534 point to non-existent hosts; that is treated as a hard error.
3535
3536 We can just skip this host entirely. When the hosts came from the router,
3537 the address will timeout based on the other host(s); when the address is
3538 looked up below, there is an explicit retry record added.
3539
3540 Note that we mustn't skip unusable hosts if the address is not unset; they
3541 may be needed as expired hosts on the 2nd time round the cutoff loop. */
3542
3543 if (!host->address)
3544 {
3545 int new_port, flags;
3546 host_item *hh;
3547
3548 if (host->status >= hstatus_unusable)
3549 {
3550 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
3551 host->name);
3552 continue;
3553 }
3554
3555 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
3556
3557 /* The host name is permitted to have an attached port. Find it, and
3558 strip it from the name. Just remember it for now. */
3559
3560 new_port = host_item_get_port(host);
3561
3562 /* Count hosts looked up */
3563
3564 hosts_looked_up++;
3565
3566 /* Find by name if so configured, or if it's an IP address. We don't
3567 just copy the IP address, because we need the test-for-local to happen. */
3568
3569 flags = HOST_FIND_BY_A;
3570 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
3571 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
3572
3573 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
3574 rc = host_find_byname(host, NULL, flags, NULL, TRUE);
3575 else
3576 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
3577 &ob->dnssec, /* domains for request/require */
3578 NULL, NULL);
3579
3580 /* Update the host (and any additional blocks, resulting from
3581 multihoming) with a host-specific port, if any. */
3582
3583 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
3584
3585 /* Failure to find the host at this time (usually DNS temporary failure)
3586 is really a kind of routing failure rather than a transport failure.
3587 Therefore we add a retry item of the routing kind, not to stop us trying
3588 to look this name up here again, but to ensure the address gets timed
3589 out if the failures go on long enough. A complete failure at this point
3590 commonly points to a configuration error, but the best action is still
3591 to carry on for the next host. */
3592
3593 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
3594 {
3595 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
3596 expired = FALSE;
3597 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
3598 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
3599 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
3600 host->status = hstatus_unusable;
3601
3602 for (addr = addrlist; addr; addr = addr->next)
3603 {
3604 if (addr->transport_return != DEFER) continue;
3605 addr->basic_errno = ERRNO_UNKNOWNHOST;
3606 addr->message =
3607 string_sprintf("failed to lookup IP address for %s", host->name);
3608 }
3609 continue;
3610 }
3611
3612 /* If the host is actually the local host, we may have a problem, or
3613 there may be some cunning configuration going on. In the problem case,
3614 log things and give up. The default transport status is already DEFER. */
3615
3616 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
3617 {
3618 for (addr = addrlist; addr; addr = addr->next)
3619 {
3620 addr->basic_errno = 0;
3621 addr->message = string_sprintf("%s transport found host %s to be "
3622 "local", tblock->name, host->name);
3623 }
3624 goto END_TRANSPORT;
3625 }
3626 } /* End of block for IP address lookup */
3627
3628 /* If this is a continued delivery, we are interested only in the host
3629 which matches the name of the existing open channel. The check is put
3630 here after the local host lookup, in case the name gets expanded as a
3631 result of the lookup. Set expired FALSE, to save the outer loop executing
3632 twice. */
3633
3634 if ( continue_hostname
3635 && ( Ustrcmp(continue_hostname, host->name) != 0
3636 || Ustrcmp(continue_host_address, host->address) != 0
3637 ) )
3638 {
3639 expired = FALSE;
3640 continue; /* With next host */
3641 }
3642
3643 /* Reset the default next host in case a multihomed host whose addresses
3644 are not looked up till just above added to the host list. */
3645
3646 nexthost = host->next;
3647
3648 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
3649 domain is in queue_smtp_domains, we don't actually want to attempt any
3650 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
3651 there is a lookup defer in queue_smtp_domains, proceed as if the domain
3652 were not in it. We don't want to hold up all SMTP deliveries! Except when
3653 doing a two-stage queue run, don't do this if forcing. */
3654
3655 if ((!deliver_force || queue_2stage) && (queue_smtp ||
3656 match_isinlist(addrlist->domain,
3657 (const uschar **)&queue_smtp_domains, 0,
3658 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
3659 {
3660 expired = FALSE;
3661 for (addr = addrlist; addr; addr = addr->next)
3662 if (addr->transport_return == DEFER)
3663 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
3664 continue; /* With next host */
3665 }
3666
3667 /* Count hosts being considered - purely for an intelligent comment
3668 if none are usable. */
3669
3670 hosts_total++;
3671
3672 /* Set $host and $host address now in case they are needed for the
3673 interface expansion or the serialize_hosts check; they remain set if an
3674 actual delivery happens. */
3675
3676 deliver_host = host->name;
3677 deliver_host_address = host->address;
3678 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
3679 : host->dnssec == DS_NO ? US"no"
3680 : US"";
3681
3682 /* Set up a string for adding to the retry key if the port number is not
3683 the standard SMTP port. A host may have its own port setting that overrides
3684 the default. */
3685
3686 pistring = string_sprintf(":%d", host->port == PORT_NONE
3687 ? port : host->port);
3688 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
3689
3690 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
3691 string is set, even if constant (as different transports can have different
3692 constant settings), we must add it to the key that is used for retries,
3693 because connections to the same host from a different interface should be
3694 treated separately. */
3695
3696 host_af = Ustrchr(host->address, ':') == NULL ? AF_INET : AF_INET6;
3697 if ((rs = ob->interface) && *rs)
3698 {
3699 if (!smtp_get_interface(rs, host_af, addrlist, &interface, tid))
3700 return FALSE;
3701 pistring = string_sprintf("%s/%s", pistring, interface);
3702 }
3703
3704 /* The first time round the outer loop, check the status of the host by
3705 inspecting the retry data. The second time round, we are interested only
3706 in expired hosts that haven't been tried since this message arrived. */
3707
3708 if (cutoff_retry == 0)
3709 {
3710 BOOL incl_ip;
3711 /* Ensure the status of the address is set by checking retry data if
3712 necessary. There may be host-specific retry data (applicable to all
3713 messages) and also data for retries of a specific message at this host.
3714 If either of these retry records are actually read, the keys used are
3715 returned to save recomputing them later. */
3716
3717 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3718 US"retry_include_ip_address", ob->retry_include_ip_address,
3719 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3720 continue; /* with next host */
3721
3722 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
3723 incl_ip, &retry_host_key, &retry_message_key);
3724
3725 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
3726 (host->address == NULL)? US"" : host->address, pistring,
3727 (host->status == hstatus_usable)? "usable" :
3728 (host->status == hstatus_unusable)? "unusable" :
3729 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
3730
3731 /* Skip this address if not usable at this time, noting if it wasn't
3732 actually expired, both locally and in the address. */
3733
3734 switch (host->status)
3735 {
3736 case hstatus_unusable:
3737 expired = FALSE;
3738 setflag(addrlist, af_retry_skipped);
3739 /* Fall through */
3740
3741 case hstatus_unusable_expired:
3742 switch (host->why)
3743 {
3744 case hwhy_retry: hosts_retry++; break;
3745 case hwhy_failed: hosts_fail++; break;
3746 case hwhy_deferred: hosts_defer++; break;
3747 }
3748
3749 /* If there was a retry message key, implying that previously there
3750 was a message-specific defer, we don't want to update the list of
3751 messages waiting for these hosts. */
3752
3753 if (retry_message_key) update_waiting = FALSE;
3754 continue; /* With the next host or IP address */
3755 }
3756 }
3757
3758 /* Second time round the loop: if the address is set but expired, and
3759 the message is newer than the last try, let it through. */
3760
3761 else
3762 {
3763 if ( !host->address
3764 || host->status != hstatus_unusable_expired
3765 || host->last_try > received_time)
3766 continue;
3767 DEBUG(D_transport) debug_printf("trying expired host %s [%s]%s\n",
3768 host->name, host->address, pistring);
3769 host_is_expired = TRUE;
3770 }
3771
3772 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
3773 it remains TRUE only if all hosts are expired and none are actually tried.
3774 */
3775
3776 expired = FALSE;
3777
3778 /* If this host is listed as one to which access must be serialized,
3779 see if another Exim process has a connection to it, and if so, skip
3780 this host. If not, update the database to record our connection to it
3781 and remember this for later deletion. Do not do any of this if we are
3782 sending the message down a pre-existing connection. */
3783
3784 if ( !continue_hostname
3785 && verify_check_given_host(&ob->serialize_hosts, host) == OK)
3786 {
3787 serialize_key = string_sprintf("host-serialize-%s", host->name);
3788 if (!enq_start(serialize_key, 1))
3789 {
3790 DEBUG(D_transport)
3791 debug_printf("skipping host %s because another Exim process "
3792 "is connected to it\n", host->name);
3793 hosts_serial++;
3794 continue;
3795 }
3796 }
3797
3798 /* OK, we have an IP address that is not waiting for its retry time to
3799 arrive (it might be expired) OR (second time round the loop) we have an
3800 expired host that hasn't been tried since the message arrived. Have a go
3801 at delivering the message to it. First prepare the addresses by flushing
3802 out the result of previous attempts, and finding the first address that
3803 is still to be delivered. */
3804
3805 first_addr = prepare_addresses(addrlist, host);
3806
3807 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
3808 message_id, host->name, host->address, addrlist->address,
3809 addrlist->next ? ", ..." : "");
3810
3811 set_process_info("delivering %s to %s [%s] (%s%s)",
3812 message_id, host->name, host->address, addrlist->address,
3813 addrlist->next ? ", ..." : "");
3814
3815 /* This is not for real; don't do the delivery. If there are
3816 any remaining hosts, list them. */
3817
3818 if (dont_deliver)
3819 {
3820 host_item *host2;
3821 set_errno_nohost(addrlist, 0, NULL, OK, FALSE);
3822 for (addr = addrlist; addr; addr = addr->next)
3823 {
3824 addr->host_used = host;
3825 addr->special_action = '*';
3826 addr->message = US"delivery bypassed by -N option";
3827 }
3828 DEBUG(D_transport)
3829 {
3830 debug_printf("*** delivery by %s transport bypassed by -N option\n"
3831 "*** host and remaining hosts:\n", tblock->name);
3832 for (host2 = host; host2; host2 = host2->next)
3833 debug_printf(" %s [%s]\n", host2->name,
3834 host2->address ? host2->address : US"unset");
3835 }
3836 rc = OK;
3837 }
3838
3839 /* This is for real. If the host is expired, we don't count it for
3840 hosts_max_retry. This ensures that all hosts must expire before an address
3841 is timed out, unless hosts_max_try_hardlimit (which protects against
3842 lunatic DNS configurations) is reached.
3843
3844 If the host is not expired and we are about to hit the hosts_max_retry
3845 limit, check to see if there is a subsequent hosts with a different MX
3846 value. If so, make that the next host, and don't count this one. This is a
3847 heuristic to make sure that different MXs do get tried. With a normal kind
3848 of retry rule, they would get tried anyway when the earlier hosts were
3849 delayed, but if the domain has a "retry every time" type of rule - as is
3850 often used for the the very large ISPs, that won't happen. */
3851
3852 else
3853 {
3854 host_item * thost;
3855 /* Make a copy of the host if it is local to this invocation
3856 of the transport. */
3857
3858 if (expanded_hosts)
3859 {
3860 thost = store_get(sizeof(host_item));
3861 *thost = *host;
3862 thost->name = string_copy(host->name);
3863 thost->address = string_copy(host->address);
3864 }
3865 else
3866 thost = host;
3867
3868 if (!host_is_expired && ++unexpired_hosts_tried >= ob