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[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
16 /* Options specific to the smtp transport. This transport also supports LMTP
17 over TCP/IP. The options must be in alphabetic order (note that "_" comes
18 before the lower case letters). Some live in the transport_instance block so as
19 to be publicly visible; these are flagged with opt_public. */
20
21 optionlist smtp_transport_options[] = {
22 { "*expand_multi_domain", opt_stringptr | opt_hidden | opt_public,
23 (void *)offsetof(transport_instance, expand_multi_domain) },
24 { "*expand_retry_include_ip_address", opt_stringptr | opt_hidden,
25 (void *)(offsetof(smtp_transport_options_block, expand_retry_include_ip_address)) },
26
27 { "address_retry_include_sender", opt_bool,
28 (void *)offsetof(smtp_transport_options_block, address_retry_include_sender) },
29 { "allow_localhost", opt_bool,
30 (void *)offsetof(smtp_transport_options_block, allow_localhost) },
31 { "authenticated_sender", opt_stringptr,
32 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
33 { "authenticated_sender_force", opt_bool,
34 (void *)offsetof(smtp_transport_options_block, authenticated_sender_force) },
35 { "command_timeout", opt_time,
36 (void *)offsetof(smtp_transport_options_block, command_timeout) },
37 { "connect_timeout", opt_time,
38 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
39 { "connection_max_messages", opt_int | opt_public,
40 (void *)offsetof(transport_instance, connection_max_messages) },
41 { "data_timeout", opt_time,
42 (void *)offsetof(smtp_transport_options_block, data_timeout) },
43 { "delay_after_cutoff", opt_bool,
44 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
45 #ifndef DISABLE_DKIM
46 { "dkim_canon", opt_stringptr,
47 (void *)offsetof(smtp_transport_options_block, dkim.dkim_canon) },
48 { "dkim_domain", opt_stringptr,
49 (void *)offsetof(smtp_transport_options_block, dkim.dkim_domain) },
50 { "dkim_private_key", opt_stringptr,
51 (void *)offsetof(smtp_transport_options_block, dkim.dkim_private_key) },
52 { "dkim_selector", opt_stringptr,
53 (void *)offsetof(smtp_transport_options_block, dkim.dkim_selector) },
54 { "dkim_sign_headers", opt_stringptr,
55 (void *)offsetof(smtp_transport_options_block, dkim.dkim_sign_headers) },
56 { "dkim_strict", opt_stringptr,
57 (void *)offsetof(smtp_transport_options_block, dkim.dkim_strict) },
58 #endif
59 { "dns_qualify_single", opt_bool,
60 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
61 { "dns_search_parents", opt_bool,
62 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
63 { "dnssec_request_domains", opt_stringptr,
64 (void *)offsetof(smtp_transport_options_block, dnssec.request) },
65 { "dnssec_require_domains", opt_stringptr,
66 (void *)offsetof(smtp_transport_options_block, dnssec.require) },
67 { "dscp", opt_stringptr,
68 (void *)offsetof(smtp_transport_options_block, dscp) },
69 { "fallback_hosts", opt_stringptr,
70 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
71 { "final_timeout", opt_time,
72 (void *)offsetof(smtp_transport_options_block, final_timeout) },
73 { "gethostbyname", opt_bool,
74 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
75 { "helo_data", opt_stringptr,
76 (void *)offsetof(smtp_transport_options_block, helo_data) },
77 { "hosts", opt_stringptr,
78 (void *)offsetof(smtp_transport_options_block, hosts) },
79 { "hosts_avoid_esmtp", opt_stringptr,
80 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
81 { "hosts_avoid_pipelining", opt_stringptr,
82 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
83 #ifdef SUPPORT_TLS
84 { "hosts_avoid_tls", opt_stringptr,
85 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
86 #endif
87 { "hosts_max_try", opt_int,
88 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
89 { "hosts_max_try_hardlimit", opt_int,
90 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
91 #ifdef SUPPORT_TLS
92 { "hosts_nopass_tls", opt_stringptr,
93 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
94 #endif
95 { "hosts_override", opt_bool,
96 (void *)offsetof(smtp_transport_options_block, hosts_override) },
97 { "hosts_randomize", opt_bool,
98 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
99 #if defined(SUPPORT_TLS) && !defined(DISABLE_OCSP)
100 { "hosts_request_ocsp", opt_stringptr,
101 (void *)offsetof(smtp_transport_options_block, hosts_request_ocsp) },
102 #endif
103 { "hosts_require_auth", opt_stringptr,
104 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
105 #ifdef SUPPORT_TLS
106 # ifdef EXPERIMENTAL_DANE
107 { "hosts_require_dane", opt_stringptr,
108 (void *)offsetof(smtp_transport_options_block, hosts_require_dane) },
109 # endif
110 # ifndef DISABLE_OCSP
111 { "hosts_require_ocsp", opt_stringptr,
112 (void *)offsetof(smtp_transport_options_block, hosts_require_ocsp) },
113 # endif
114 { "hosts_require_tls", opt_stringptr,
115 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
116 #endif
117 { "hosts_try_auth", opt_stringptr,
118 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
119 { "hosts_try_chunking", opt_stringptr,
120 (void *)offsetof(smtp_transport_options_block, hosts_try_chunking) },
121 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
122 { "hosts_try_dane", opt_stringptr,
123 (void *)offsetof(smtp_transport_options_block, hosts_try_dane) },
124 #endif
125 #ifndef DISABLE_PRDR
126 { "hosts_try_prdr", opt_stringptr,
127 (void *)offsetof(smtp_transport_options_block, hosts_try_prdr) },
128 #endif
129 #ifdef SUPPORT_TLS
130 { "hosts_verify_avoid_tls", opt_stringptr,
131 (void *)offsetof(smtp_transport_options_block, hosts_verify_avoid_tls) },
132 #endif
133 { "interface", opt_stringptr,
134 (void *)offsetof(smtp_transport_options_block, interface) },
135 { "keepalive", opt_bool,
136 (void *)offsetof(smtp_transport_options_block, keepalive) },
137 { "lmtp_ignore_quota", opt_bool,
138 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
139 { "max_rcpt", opt_int | opt_public,
140 (void *)offsetof(transport_instance, max_addresses) },
141 { "multi_domain", opt_expand_bool | opt_public,
142 (void *)offsetof(transport_instance, multi_domain) },
143 { "port", opt_stringptr,
144 (void *)offsetof(smtp_transport_options_block, port) },
145 { "protocol", opt_stringptr,
146 (void *)offsetof(smtp_transport_options_block, protocol) },
147 { "retry_include_ip_address", opt_expand_bool,
148 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
149 { "serialize_hosts", opt_stringptr,
150 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
151 { "size_addition", opt_int,
152 (void *)offsetof(smtp_transport_options_block, size_addition) }
153 #ifdef SUPPORT_SOCKS
154 ,{ "socks_proxy", opt_stringptr,
155 (void *)offsetof(smtp_transport_options_block, socks_proxy) }
156 #endif
157 #ifdef SUPPORT_TLS
158 ,{ "tls_certificate", opt_stringptr,
159 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
160 { "tls_crl", opt_stringptr,
161 (void *)offsetof(smtp_transport_options_block, tls_crl) },
162 { "tls_dh_min_bits", opt_int,
163 (void *)offsetof(smtp_transport_options_block, tls_dh_min_bits) },
164 { "tls_privatekey", opt_stringptr,
165 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
166 { "tls_require_ciphers", opt_stringptr,
167 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
168 { "tls_sni", opt_stringptr,
169 (void *)offsetof(smtp_transport_options_block, tls_sni) },
170 { "tls_tempfail_tryclear", opt_bool,
171 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
172 { "tls_try_verify_hosts", opt_stringptr,
173 (void *)offsetof(smtp_transport_options_block, tls_try_verify_hosts) },
174 { "tls_verify_cert_hostnames", opt_stringptr,
175 (void *)offsetof(smtp_transport_options_block,tls_verify_cert_hostnames)},
176 { "tls_verify_certificates", opt_stringptr,
177 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) },
178 { "tls_verify_hosts", opt_stringptr,
179 (void *)offsetof(smtp_transport_options_block, tls_verify_hosts) }
180 #endif
181 };
182
183 /* Size of the options list. An extern variable has to be used so that its
184 address can appear in the tables drtables.c. */
185
186 int smtp_transport_options_count =
187 sizeof(smtp_transport_options)/sizeof(optionlist);
188
189 /* Default private options block for the smtp transport. */
190
191 smtp_transport_options_block smtp_transport_option_defaults = {
192 NULL, /* hosts */
193 NULL, /* fallback_hosts */
194 NULL, /* hostlist */
195 NULL, /* fallback_hostlist */
196 NULL, /* authenticated_sender */
197 US"$primary_hostname", /* helo_data */
198 NULL, /* interface */
199 NULL, /* port */
200 US"smtp", /* protocol */
201 NULL, /* DSCP */
202 NULL, /* serialize_hosts */
203 NULL, /* hosts_try_auth */
204 NULL, /* hosts_require_auth */
205 US"*", /* hosts_try_chunking */
206 #ifdef EXPERIMENTAL_DANE
207 NULL, /* hosts_try_dane */
208 NULL, /* hosts_require_dane */
209 #endif
210 #ifndef DISABLE_PRDR
211 US"*", /* hosts_try_prdr */
212 #endif
213 #ifndef DISABLE_OCSP
214 US"*", /* hosts_request_ocsp (except under DANE; tls_client_start()) */
215 NULL, /* hosts_require_ocsp */
216 #endif
217 NULL, /* hosts_require_tls */
218 NULL, /* hosts_avoid_tls */
219 NULL, /* hosts_verify_avoid_tls */
220 NULL, /* hosts_avoid_pipelining */
221 NULL, /* hosts_avoid_esmtp */
222 NULL, /* hosts_nopass_tls */
223 5*60, /* command_timeout */
224 5*60, /* connect_timeout; shorter system default overrides */
225 5*60, /* data timeout */
226 10*60, /* final timeout */
227 1024, /* size_addition */
228 5, /* hosts_max_try */
229 50, /* hosts_max_try_hardlimit */
230 TRUE, /* address_retry_include_sender */
231 FALSE, /* allow_localhost */
232 FALSE, /* authenticated_sender_force */
233 FALSE, /* gethostbyname */
234 TRUE, /* dns_qualify_single */
235 FALSE, /* dns_search_parents */
236 { NULL, NULL }, /* dnssec_domains {request,require} */
237 TRUE, /* delay_after_cutoff */
238 FALSE, /* hosts_override */
239 FALSE, /* hosts_randomize */
240 TRUE, /* keepalive */
241 FALSE, /* lmtp_ignore_quota */
242 NULL, /* expand_retry_include_ip_address */
243 TRUE /* retry_include_ip_address */
244 #ifdef SUPPORT_SOCKS
245 ,NULL /* socks_proxy */
246 #endif
247 #ifdef SUPPORT_TLS
248 ,NULL, /* tls_certificate */
249 NULL, /* tls_crl */
250 NULL, /* tls_privatekey */
251 NULL, /* tls_require_ciphers */
252 NULL, /* tls_sni */
253 US"system", /* tls_verify_certificates */
254 EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
255 /* tls_dh_min_bits */
256 TRUE, /* tls_tempfail_tryclear */
257 NULL, /* tls_verify_hosts */
258 US"*", /* tls_try_verify_hosts */
259 US"*" /* tls_verify_cert_hostnames */
260 #endif
261 #ifndef DISABLE_DKIM
262 , {NULL, /* dkim_canon */
263 NULL, /* dkim_domain */
264 NULL, /* dkim_private_key */
265 NULL, /* dkim_selector */
266 NULL, /* dkim_sign_headers */
267 NULL} /* dkim_strict */
268 #endif
269 };
270
271 /* some DSN flags for use later */
272
273 static int rf_list[] = {rf_notify_never, rf_notify_success,
274 rf_notify_failure, rf_notify_delay };
275
276 static uschar *rf_names[] = { US"NEVER", US"SUCCESS", US"FAILURE", US"DELAY" };
277
278
279
280 /* Local statics */
281
282 static uschar *smtp_command; /* Points to last cmd for error messages */
283 static uschar *mail_command; /* Points to MAIL cmd for error messages */
284 static BOOL update_waiting; /* TRUE to update the "wait" database */
285 static BOOL pipelining_active; /* current transaction is in pipe mode */
286
287
288 /*************************************************
289 * Setup entry point *
290 *************************************************/
291
292 /* This function is called when the transport is about to be used,
293 but before running it in a sub-process. It is used for two things:
294
295 (1) To set the fallback host list in addresses, when delivering.
296 (2) To pass back the interface, port, protocol, and other options, for use
297 during callout verification.
298
299 Arguments:
300 tblock pointer to the transport instance block
301 addrlist list of addresses about to be transported
302 tf if not NULL, pointer to block in which to return options
303 uid the uid that will be set (not used)
304 gid the gid that will be set (not used)
305 errmsg place for error message (not used)
306
307 Returns: OK always (FAIL, DEFER not used)
308 */
309
310 static int
311 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
312 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
313 {
314 smtp_transport_options_block *ob =
315 (smtp_transport_options_block *)(tblock->options_block);
316
317 errmsg = errmsg; /* Keep picky compilers happy */
318 uid = uid;
319 gid = gid;
320
321 /* Pass back options if required. This interface is getting very messy. */
322
323 if (tf != NULL)
324 {
325 tf->interface = ob->interface;
326 tf->port = ob->port;
327 tf->protocol = ob->protocol;
328 tf->hosts = ob->hosts;
329 tf->hosts_override = ob->hosts_override;
330 tf->hosts_randomize = ob->hosts_randomize;
331 tf->gethostbyname = ob->gethostbyname;
332 tf->qualify_single = ob->dns_qualify_single;
333 tf->search_parents = ob->dns_search_parents;
334 tf->helo_data = ob->helo_data;
335 }
336
337 /* Set the fallback host list for all the addresses that don't have fallback
338 host lists, provided that the local host wasn't present in the original host
339 list. */
340
341 if (!testflag(addrlist, af_local_host_removed))
342 {
343 for (; addrlist != NULL; addrlist = addrlist->next)
344 if (addrlist->fallback_hosts == NULL)
345 addrlist->fallback_hosts = ob->fallback_hostlist;
346 }
347
348 return OK;
349 }
350
351
352
353 /*************************************************
354 * Initialization entry point *
355 *************************************************/
356
357 /* Called for each instance, after its options have been read, to
358 enable consistency checks to be done, or anything else that needs
359 to be set up.
360
361 Argument: pointer to the transport instance block
362 Returns: nothing
363 */
364
365 void
366 smtp_transport_init(transport_instance *tblock)
367 {
368 smtp_transport_options_block *ob =
369 (smtp_transport_options_block *)(tblock->options_block);
370
371 /* Retry_use_local_part defaults FALSE if unset */
372
373 if (tblock->retry_use_local_part == TRUE_UNSET)
374 tblock->retry_use_local_part = FALSE;
375
376 /* Set the default port according to the protocol */
377
378 if (ob->port == NULL)
379 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
380 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
381
382 /* Set up the setup entry point, to be called before subprocesses for this
383 transport. */
384
385 tblock->setup = smtp_transport_setup;
386
387 /* Complain if any of the timeouts are zero. */
388
389 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
390 ob->final_timeout <= 0)
391 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
392 "command, data, or final timeout value is zero for %s transport",
393 tblock->name);
394
395 /* If hosts_override is set and there are local hosts, set the global
396 flag that stops verify from showing router hosts. */
397
398 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
399
400 /* If there are any fallback hosts listed, build a chain of host items
401 for them, but do not do any lookups at this time. */
402
403 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
404 }
405
406
407
408
409
410 /*************************************************
411 * Set delivery info into all active addresses *
412 *************************************************/
413
414 /* Only addresses whose status is >= PENDING are relevant. A lesser
415 status means that an address is not currently being processed.
416
417 Arguments:
418 addrlist points to a chain of addresses
419 errno_value to put in each address's errno field
420 msg to put in each address's message field
421 rc to put in each address's transport_return field
422 pass_message if TRUE, set the "pass message" flag in the address
423 host if set, mark addrs as having used this host
424 smtp_greeting from peer
425 helo_response from peer
426
427 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
428 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
429 this particular type of timeout.
430
431 Returns: nothing
432 */
433
434 static void
435 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
436 BOOL pass_message, host_item * host
437 #ifdef EXPERIMENTAL_DSN_INFO
438 , const uschar * smtp_greeting, const uschar * helo_response
439 #endif
440 )
441 {
442 address_item *addr;
443 int orvalue = 0;
444 if (errno_value == ERRNO_CONNECTTIMEOUT)
445 {
446 errno_value = ETIMEDOUT;
447 orvalue = RTEF_CTOUT;
448 }
449 for (addr = addrlist; addr; addr = addr->next)
450 if (addr->transport_return >= PENDING)
451 {
452 addr->basic_errno = errno_value;
453 addr->more_errno |= orvalue;
454 if (msg != NULL)
455 {
456 addr->message = msg;
457 if (pass_message) setflag(addr, af_pass_message);
458 }
459 addr->transport_return = rc;
460 if (host)
461 {
462 addr->host_used = host;
463 #ifdef EXPERIMENTAL_DSN_INFO
464 if (smtp_greeting)
465 {uschar * s = Ustrchr(smtp_greeting, '\n'); if (s) *s = '\0';}
466 addr->smtp_greeting = smtp_greeting;
467
468 if (helo_response)
469 {uschar * s = Ustrchr(helo_response, '\n'); if (s) *s = '\0';}
470 addr->helo_response = helo_response;
471 #endif
472 }
473 }
474 }
475
476 static void
477 set_errno_nohost(address_item *addrlist, int errno_value, uschar *msg, int rc,
478 BOOL pass_message)
479 {
480 set_errno(addrlist, errno_value, msg, rc, pass_message, NULL
481 #ifdef EXPERIMENTAL_DSN_INFO
482 , NULL, NULL
483 #endif
484 );
485 }
486
487
488 /*************************************************
489 * Check an SMTP response *
490 *************************************************/
491
492 /* This function is given an errno code and the SMTP response buffer
493 to analyse, together with the host identification for generating messages. It
494 sets an appropriate message and puts the first digit of the response code into
495 the yield variable. If no response was actually read, a suitable digit is
496 chosen.
497
498 Arguments:
499 host the current host, to get its name for messages
500 errno_value pointer to the errno value
501 more_errno from the top address for use with ERRNO_FILTER_FAIL
502 buffer the SMTP response buffer
503 yield where to put a one-digit SMTP response code
504 message where to put an errror message
505 pass_message set TRUE if message is an SMTP response
506
507 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
508 */
509
510 static BOOL
511 check_response(host_item *host, int *errno_value, int more_errno,
512 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
513 {
514 uschar * pl = pipelining_active ? US"pipelined " : US"";
515
516 *yield = '4'; /* Default setting is to give a temporary error */
517
518 /* Handle response timeout */
519
520 if (*errno_value == ETIMEDOUT)
521 {
522 *message = US string_sprintf("SMTP timeout after %s%s",
523 pl, smtp_command);
524 if (transport_count > 0)
525 *message = US string_sprintf("%s (%d bytes written)", *message,
526 transport_count);
527 return FALSE;
528 }
529
530 /* Handle malformed SMTP response */
531
532 if (*errno_value == ERRNO_SMTPFORMAT)
533 {
534 const uschar *malfresp = string_printing(buffer);
535 while (isspace(*malfresp)) malfresp++;
536 *message = *malfresp == 0
537 ? string_sprintf("Malformed SMTP reply (an empty line) "
538 "in response to %s%s", pl, smtp_command)
539 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
540 pl, smtp_command, malfresp);
541 return FALSE;
542 }
543
544 /* Handle a failed filter process error; can't send QUIT as we mustn't
545 end the DATA. */
546
547 if (*errno_value == ERRNO_FILTER_FAIL)
548 {
549 *message = US string_sprintf("transport filter process failed (%d)%s",
550 more_errno,
551 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
552 return FALSE;
553 }
554
555 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
556 end the DATA. */
557
558 if (*errno_value == ERRNO_CHHEADER_FAIL)
559 {
560 *message =
561 US string_sprintf("failed to expand headers_add or headers_remove: %s",
562 expand_string_message);
563 return FALSE;
564 }
565
566 /* Handle failure to write a complete data block */
567
568 if (*errno_value == ERRNO_WRITEINCOMPLETE)
569 {
570 *message = US string_sprintf("failed to write a data block");
571 return FALSE;
572 }
573
574 #ifdef SUPPORT_I18N
575 /* Handle lack of advertised SMTPUTF8, for international message */
576 if (*errno_value == ERRNO_UTF8_FWD)
577 {
578 *message = US string_sprintf("utf8 support required but not offered for forwarding");
579 DEBUG(D_deliver|D_transport) debug_printf("%s\n", *message);
580 return TRUE;
581 }
582 #endif
583
584 /* Handle error responses from the remote mailer. */
585
586 if (buffer[0] != 0)
587 {
588 const uschar *s = string_printing(buffer);
589 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
590 "%s", pl, smtp_command, s);
591 *pass_message = TRUE;
592 *yield = buffer[0];
593 return TRUE;
594 }
595
596 /* No data was read. If there is no errno, this must be the EOF (i.e.
597 connection closed) case, which causes deferral. An explicit connection reset
598 error has the same effect. Otherwise, put the host's identity in the message,
599 leaving the errno value to be interpreted as well. In all cases, we have to
600 assume the connection is now dead. */
601
602 if (*errno_value == 0 || *errno_value == ECONNRESET)
603 {
604 *errno_value = ERRNO_SMTPCLOSED;
605 *message = US string_sprintf("Remote host closed connection "
606 "in response to %s%s", pl, smtp_command);
607 }
608 else *message = US string_sprintf("%s [%s]", host->name, host->address);
609
610 return FALSE;
611 }
612
613
614
615 /*************************************************
616 * Write error message to logs *
617 *************************************************/
618
619 /* This writes to the main log and to the message log.
620
621 Arguments:
622 addr the address item containing error information
623 host the current host
624
625 Returns: nothing
626 */
627
628 static void
629 write_logs(address_item *addr, host_item *host)
630 {
631 uschar * message = string_sprintf("H=%s [%s]", host->name, host->address);
632
633 if (LOGGING(outgoing_port))
634 message = string_sprintf("%s:%d", message,
635 host->port == PORT_NONE ? 25 : host->port);
636 if (addr->message)
637 {
638 message = string_sprintf("%s: %s", message, addr->message);
639 if (addr->basic_errno > 0)
640 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
641 log_write(0, LOG_MAIN, "%s", message);
642 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
643 }
644 else
645 {
646 const uschar * s = exim_errstr(addr->basic_errno);
647 log_write(0, LOG_MAIN, "%s %s", message, s);
648 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), message, s);
649 }
650 }
651
652 static void
653 msglog_line(host_item * host, uschar * message)
654 {
655 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
656 host->name, host->address, message);
657 }
658
659
660
661 #ifndef DISABLE_EVENT
662 /*************************************************
663 * Post-defer action *
664 *************************************************/
665
666 /* This expands an arbitrary per-transport string.
667 It might, for example, be used to write to the database log.
668
669 Arguments:
670 addr the address item containing error information
671 host the current host
672
673 Returns: nothing
674 */
675
676 static void
677 deferred_event_raise(address_item *addr, host_item *host)
678 {
679 uschar * action = addr->transport->event_action;
680 const uschar * save_domain;
681 uschar * save_local;
682
683 if (!action)
684 return;
685
686 save_domain = deliver_domain;
687 save_local = deliver_localpart;
688
689 /*XXX would ip & port already be set up? */
690 deliver_host_address = string_copy(host->address);
691 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
692 event_defer_errno = addr->basic_errno;
693
694 router_name = addr->router->name;
695 transport_name = addr->transport->name;
696 deliver_domain = addr->domain;
697 deliver_localpart = addr->local_part;
698
699 (void) event_raise(action, US"msg:host:defer",
700 addr->message
701 ? addr->basic_errno > 0
702 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
703 : string_copy(addr->message)
704 : addr->basic_errno > 0
705 ? string_copy(US strerror(addr->basic_errno))
706 : NULL);
707
708 deliver_localpart = save_local;
709 deliver_domain = save_domain;
710 router_name = transport_name = NULL;
711 }
712 #endif
713
714 /*************************************************
715 * Synchronize SMTP responses *
716 *************************************************/
717
718 /* This function is called from smtp_deliver() to receive SMTP responses from
719 the server, and match them up with the commands to which they relate. When
720 PIPELINING is not in use, this function is called after every command, and is
721 therefore somewhat over-engineered, but it is simpler to use a single scheme
722 that works both with and without PIPELINING instead of having two separate sets
723 of code.
724
725 The set of commands that are buffered up with pipelining may start with MAIL
726 and may end with DATA; in between are RCPT commands that correspond to the
727 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
728 etc.) are never buffered.
729
730 Errors after MAIL or DATA abort the whole process leaving the response in the
731 buffer. After MAIL, pending responses are flushed, and the original command is
732 re-instated in big_buffer for error messages. For RCPT commands, the remote is
733 permitted to reject some recipient addresses while accepting others. However
734 certain errors clearly abort the whole process. Set the value in
735 transport_return to PENDING_OK if the address is accepted. If there is a
736 subsequent general error, it will get reset accordingly. If not, it will get
737 converted to OK at the end.
738
739 Arguments:
740 addrlist the complete address list
741 include_affixes TRUE if affixes include in RCPT
742 sync_addr ptr to the ptr of the one to start scanning at (updated)
743 host the host we are connected to
744 count the number of responses to read
745 address_retry_
746 include_sender true if 4xx retry is to include the sender it its key
747 pending_MAIL true if the first response is for MAIL
748 pending_DATA 0 if last command sent was not DATA
749 +1 if previously had a good recipient
750 -1 if not previously had a good recipient
751 inblock incoming SMTP block
752 timeout timeout value
753 buffer buffer for reading response
754 buffsize size of buffer
755
756 Returns: 3 if at least one address had 2xx and one had 5xx
757 2 if at least one address had 5xx but none had 2xx
758 1 if at least one host had a 2xx response, but none had 5xx
759 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
760 -1 timeout while reading RCPT response
761 -2 I/O or other non-response error for RCPT
762 -3 DATA or MAIL failed - errno and buffer set
763 */
764
765 static int
766 sync_responses(address_item *addrlist, BOOL include_affixes,
767 address_item **sync_addr, host_item *host, int count,
768 BOOL address_retry_include_sender, BOOL pending_MAIL,
769 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
770 int buffsize)
771 {
772 address_item *addr = *sync_addr;
773 int yield = 0;
774
775 /* Handle the response for a MAIL command. On error, reinstate the original
776 command in big_buffer for error message use, and flush any further pending
777 responses before returning, except after I/O errors and timeouts. */
778
779 if (pending_MAIL)
780 {
781 count--;
782 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
783 {
784 DEBUG(D_transport) debug_printf("bad response for MAIL\n");
785 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
786 if (errno == 0 && buffer[0] != 0)
787 {
788 uschar flushbuffer[4096];
789 int save_errno = 0;
790 if (buffer[0] == '4')
791 {
792 save_errno = ERRNO_MAIL4XX;
793 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
794 }
795 while (count-- > 0)
796 {
797 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
798 '2', timeout)
799 && (errno != 0 || flushbuffer[0] == 0))
800 break;
801 }
802 errno = save_errno;
803 }
804
805 if (pending_DATA) count--; /* Number of RCPT responses to come */
806 while (count-- > 0) /* Mark any pending addrs with the host used */
807 {
808 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
809 addr->host_used = host;
810 addr = addr->next;
811 }
812 return -3;
813 }
814 }
815
816 if (pending_DATA) count--; /* Number of RCPT responses to come */
817
818 /* Read and handle the required number of RCPT responses, matching each one up
819 with an address by scanning for the next address whose status is PENDING_DEFER.
820 */
821
822 while (count-- > 0)
823 {
824 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
825
826 /* The address was accepted */
827 addr->host_used = host;
828
829 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
830 {
831 yield |= 1;
832 addr->transport_return = PENDING_OK;
833
834 /* If af_dr_retry_exists is set, there was a routing delay on this address;
835 ensure that any address-specific retry record is expunged. We do this both
836 for the basic key and for the version that also includes the sender. */
837
838 if (testflag(addr, af_dr_retry_exists))
839 {
840 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
841 sender_address);
842 retry_add_item(addr, altkey, rf_delete);
843 retry_add_item(addr, addr->address_retry_key, rf_delete);
844 }
845 }
846
847 /* Timeout while reading the response */
848
849 else if (errno == ETIMEDOUT)
850 {
851 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
852 transport_rcpt_address(addr, include_affixes));
853 set_errno_nohost(addrlist, ETIMEDOUT, message, DEFER, FALSE);
854 retry_add_item(addr, addr->address_retry_key, 0);
855 update_waiting = FALSE;
856 return -1;
857 }
858
859 /* Handle other errors in obtaining an SMTP response by returning -1. This
860 will cause all the addresses to be deferred. Restore the SMTP command in
861 big_buffer for which we are checking the response, so the error message
862 makes sense. */
863
864 else if (errno != 0 || buffer[0] == 0)
865 {
866 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
867 transport_rcpt_address(addr, include_affixes));
868 return -2;
869 }
870
871 /* Handle SMTP permanent and temporary response codes. */
872
873 else
874 {
875 addr->message =
876 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
877 "%s", transport_rcpt_address(addr, include_affixes),
878 string_printing(buffer));
879 setflag(addr, af_pass_message);
880 msglog_line(host, addr->message);
881
882 /* The response was 5xx */
883
884 if (buffer[0] == '5')
885 {
886 addr->transport_return = FAIL;
887 yield |= 2;
888 }
889
890 /* The response was 4xx */
891
892 else
893 {
894 addr->transport_return = DEFER;
895 addr->basic_errno = ERRNO_RCPT4XX;
896 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
897
898 #ifndef DISABLE_EVENT
899 event_defer_errno = addr->more_errno;
900 msg_event_raise(US"msg:rcpt:host:defer", addr);
901 #endif
902
903 /* Log temporary errors if there are more hosts to be tried.
904 If not, log this last one in the == line. */
905
906 if (host->next)
907 log_write(0, LOG_MAIN, "H=%s [%s]: %s", host->name, host->address, addr->message);
908
909 #ifndef DISABLE_EVENT
910 else
911 msg_event_raise(US"msg:rcpt:defer", addr);
912 #endif
913
914 /* Do not put this message on the list of those waiting for specific
915 hosts, as otherwise it is likely to be tried too often. */
916
917 update_waiting = FALSE;
918
919 /* Add a retry item for the address so that it doesn't get tried again
920 too soon. If address_retry_include_sender is true, add the sender address
921 to the retry key. */
922
923 if (address_retry_include_sender)
924 {
925 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
926 sender_address);
927 retry_add_item(addr, altkey, 0);
928 }
929 else retry_add_item(addr, addr->address_retry_key, 0);
930 }
931 }
932 } /* Loop for next RCPT response */
933
934 /* Update where to start at for the next block of responses, unless we
935 have already handled all the addresses. */
936
937 if (addr != NULL) *sync_addr = addr->next;
938
939 /* Handle a response to DATA. If we have not had any good recipients, either
940 previously or in this block, the response is ignored. */
941
942 if (pending_DATA != 0 &&
943 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
944 {
945 int code;
946 uschar *msg;
947 BOOL pass_message;
948 if (pending_DATA > 0 || (yield & 1) != 0)
949 {
950 if (errno == 0 && buffer[0] == '4')
951 {
952 errno = ERRNO_DATA4XX;
953 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
954 }
955 return -3;
956 }
957 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
958 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
959 "is in use and there were no good recipients\n", msg);
960 }
961
962 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
963 present) received 3xx. If any RCPTs were handled and yielded anything other
964 than 4xx, yield will be set non-zero. */
965
966 return yield;
967 }
968
969
970
971 /* Do the client side of smtp-level authentication */
972 /*
973 Arguments:
974 buffer EHLO response from server (gets overwritten)
975 addrlist chain of potential addresses to deliver
976 host host to deliver to
977 ob transport options
978 ibp, obp comms channel control blocks
979
980 Returns:
981 OK Success, or failed (but not required): global "smtp_authenticated" set
982 DEFER Failed authentication (and was required)
983 ERROR Internal problem
984
985 FAIL_SEND Failed communications - transmit
986 FAIL - response
987 */
988
989 int
990 smtp_auth(uschar *buffer, unsigned bufsize, address_item *addrlist, host_item *host,
991 smtp_transport_options_block *ob, BOOL is_esmtp,
992 smtp_inblock *ibp, smtp_outblock *obp)
993 {
994 int require_auth;
995 uschar *fail_reason = US"server did not advertise AUTH support";
996
997 smtp_authenticated = FALSE;
998 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
999 require_auth = verify_check_given_host(&ob->hosts_require_auth, host);
1000
1001 if (is_esmtp && !regex_AUTH) regex_AUTH =
1002 regex_must_compile(US"\\n250[\\s\\-]AUTH\\s+([\\-\\w\\s]+)(?:\\n|$)",
1003 FALSE, TRUE);
1004
1005 if (is_esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
1006 {
1007 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
1008 expand_nmax = -1; /* reset */
1009
1010 /* Must not do this check until after we have saved the result of the
1011 regex match above. */
1012
1013 if (require_auth == OK ||
1014 verify_check_given_host(&ob->hosts_try_auth, host) == OK)
1015 {
1016 auth_instance *au;
1017 fail_reason = US"no common mechanisms were found";
1018
1019 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1020
1021 /* Scan the configured authenticators looking for one which is configured
1022 for use as a client, which is not suppressed by client_condition, and
1023 whose name matches an authentication mechanism supported by the server.
1024 If one is found, attempt to authenticate by calling its client function.
1025 */
1026
1027 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1028 {
1029 uschar *p = names;
1030 if (!au->client ||
1031 (au->client_condition != NULL &&
1032 !expand_check_condition(au->client_condition, au->name,
1033 US"client authenticator")))
1034 {
1035 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1036 au->name,
1037 (au->client)? "client_condition is false" :
1038 "not configured as a client");
1039 continue;
1040 }
1041
1042 /* Loop to scan supported server mechanisms */
1043
1044 while (*p != 0)
1045 {
1046 int rc;
1047 int len = Ustrlen(au->public_name);
1048 while (isspace(*p)) p++;
1049
1050 if (strncmpic(au->public_name, p, len) != 0 ||
1051 (p[len] != 0 && !isspace(p[len])))
1052 {
1053 while (*p != 0 && !isspace(*p)) p++;
1054 continue;
1055 }
1056
1057 /* Found data for a listed mechanism. Call its client entry. Set
1058 a flag in the outblock so that data is overwritten after sending so
1059 that reflections don't show it. */
1060
1061 fail_reason = US"authentication attempt(s) failed";
1062 obp->authenticating = TRUE;
1063 rc = (au->info->clientcode)(au, ibp, obp,
1064 ob->command_timeout, buffer, bufsize);
1065 obp->authenticating = FALSE;
1066 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1067 au->name, rc);
1068
1069 /* A temporary authentication failure must hold up delivery to
1070 this host. After a permanent authentication failure, we carry on
1071 to try other authentication methods. If all fail hard, try to
1072 deliver the message unauthenticated unless require_auth was set. */
1073
1074 switch(rc)
1075 {
1076 case OK:
1077 smtp_authenticated = TRUE; /* stops the outer loop */
1078 client_authenticator = au->name;
1079 if (au->set_client_id != NULL)
1080 client_authenticated_id = expand_string(au->set_client_id);
1081 break;
1082
1083 /* Failure after writing a command */
1084
1085 case FAIL_SEND:
1086 return FAIL_SEND;
1087
1088 /* Failure after reading a response */
1089
1090 case FAIL:
1091 if (errno != 0 || buffer[0] != '5') return FAIL;
1092 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1093 au->name, host->name, host->address, buffer);
1094 break;
1095
1096 /* Failure by some other means. In effect, the authenticator
1097 decided it wasn't prepared to handle this case. Typically this
1098 is the result of "fail" in an expansion string. Do we need to
1099 log anything here? Feb 2006: a message is now put in the buffer
1100 if logging is required. */
1101
1102 case CANCELLED:
1103 if (*buffer != 0)
1104 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1105 "authentication H=%s [%s] %s", au->name, host->name,
1106 host->address, buffer);
1107 break;
1108
1109 /* Internal problem, message in buffer. */
1110
1111 case ERROR:
1112 set_errno_nohost(addrlist, ERRNO_AUTHPROB, string_copy(buffer),
1113 DEFER, FALSE);
1114 return ERROR;
1115 }
1116
1117 break; /* If not authenticated, try next authenticator */
1118 } /* Loop for scanning supported server mechanisms */
1119 } /* Loop for further authenticators */
1120 }
1121 }
1122
1123 /* If we haven't authenticated, but are required to, give up. */
1124
1125 if (require_auth == OK && !smtp_authenticated)
1126 {
1127 set_errno_nohost(addrlist, ERRNO_AUTHFAIL,
1128 string_sprintf("authentication required but %s", fail_reason), DEFER,
1129 FALSE);
1130 return DEFER;
1131 }
1132
1133 return OK;
1134 }
1135
1136
1137 /* Construct AUTH appendix string for MAIL TO */
1138 /*
1139 Arguments
1140 buffer to build string
1141 addrlist chain of potential addresses to deliver
1142 ob transport options
1143
1144 Globals smtp_authenticated
1145 client_authenticated_sender
1146 Return True on error, otherwise buffer has (possibly empty) terminated string
1147 */
1148
1149 BOOL
1150 smtp_mail_auth_str(uschar *buffer, unsigned bufsize, address_item *addrlist,
1151 smtp_transport_options_block *ob)
1152 {
1153 uschar *local_authenticated_sender = authenticated_sender;
1154
1155 #ifdef notdef
1156 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n", authenticated_sender, ob->authenticated_sender, smtp_authenticated?"Y":"N");
1157 #endif
1158
1159 if (ob->authenticated_sender != NULL)
1160 {
1161 uschar *new = expand_string(ob->authenticated_sender);
1162 if (new == NULL)
1163 {
1164 if (!expand_string_forcedfail)
1165 {
1166 uschar *message = string_sprintf("failed to expand "
1167 "authenticated_sender: %s", expand_string_message);
1168 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1169 return TRUE;
1170 }
1171 }
1172 else if (new[0] != 0) local_authenticated_sender = new;
1173 }
1174
1175 /* Add the authenticated sender address if present */
1176
1177 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1178 local_authenticated_sender != NULL)
1179 {
1180 string_format(buffer, bufsize, " AUTH=%s",
1181 auth_xtextencode(local_authenticated_sender,
1182 Ustrlen(local_authenticated_sender)));
1183 client_authenticated_sender = string_copy(local_authenticated_sender);
1184 }
1185 else
1186 *buffer= 0;
1187
1188 return FALSE;
1189 }
1190
1191
1192
1193 #ifdef EXPERIMENTAL_DANE
1194 /* Lookup TLSA record for host/port.
1195 Return: OK success with dnssec; DANE mode
1196 DEFER Do not use this host now, may retry later
1197 FAIL_FORCED No TLSA record; DANE not usable
1198 FAIL Do not use this connection
1199 */
1200
1201 int
1202 tlsa_lookup(const host_item * host, dns_answer * dnsa, BOOL dane_required)
1203 {
1204 /* move this out to host.c given the similarity to dns_lookup() ? */
1205 uschar buffer[300];
1206 const uschar * fullname = buffer;
1207
1208 /* TLSA lookup string */
1209 (void)sprintf(CS buffer, "_%d._tcp.%.256s", host->port, host->name);
1210
1211 switch (dns_lookup(dnsa, buffer, T_TLSA, &fullname))
1212 {
1213 case DNS_SUCCEED:
1214 if (!dns_is_secure(dnsa))
1215 {
1216 log_write(0, LOG_MAIN, "DANE error: TLSA lookup not DNSSEC");
1217 return DEFER;
1218 }
1219 return OK;
1220
1221 case DNS_AGAIN:
1222 return DEFER; /* just defer this TLS'd conn */
1223
1224 case DNS_NOMATCH:
1225 return dane_required ? FAIL : FAIL_FORCED;
1226
1227 default:
1228 case DNS_FAIL:
1229 return dane_required ? FAIL : DEFER;
1230 }
1231 }
1232 #endif
1233
1234
1235
1236 typedef struct smtp_compare_s
1237 {
1238 uschar *current_sender_address;
1239 struct transport_instance *tblock;
1240 } smtp_compare_t;
1241
1242 /*
1243 Create a unique string that identifies this message, it is based on
1244 sender_address, helo_data and tls_certificate if enabled. */
1245
1246 static uschar *
1247 smtp_local_identity(uschar * sender, struct transport_instance * tblock)
1248 {
1249 address_item * addr1;
1250 uschar * if1 = US"";
1251 uschar * helo1 = US"";
1252 #ifdef SUPPORT_TLS
1253 uschar * tlsc1 = US"";
1254 #endif
1255 uschar * save_sender_address = sender_address;
1256 uschar * local_identity = NULL;
1257 smtp_transport_options_block * ob =
1258 (smtp_transport_options_block *)tblock->options_block;
1259
1260 sender_address = sender;
1261
1262 addr1 = deliver_make_addr (sender, TRUE);
1263 deliver_set_expansions(addr1);
1264
1265 if (ob->interface)
1266 if1 = expand_string(ob->interface);
1267
1268 if (ob->helo_data)
1269 helo1 = expand_string(ob->helo_data);
1270
1271 #ifdef SUPPORT_TLS
1272 if (ob->tls_certificate)
1273 tlsc1 = expand_string(ob->tls_certificate);
1274 local_identity = string_sprintf ("%s^%s^%s", if1, helo1, tlsc1);
1275 #else
1276 local_identity = string_sprintf ("%s^%s", if1, helo1);
1277 #endif
1278
1279 deliver_set_expansions(NULL);
1280 sender_address = save_sender_address;
1281
1282 return local_identity;
1283 }
1284
1285
1286
1287 /* This routine is a callback that is called from transport_check_waiting.
1288 This function will evaluate the incoming message versus the previous
1289 message. If the incoming message is using a different local identity then
1290 we will veto this new message. */
1291
1292 static BOOL
1293 smtp_are_same_identities(uschar * message_id, smtp_compare_t * s_compare)
1294 {
1295 uschar * message_local_identity,
1296 * current_local_identity,
1297 * new_sender_address;
1298
1299 current_local_identity =
1300 smtp_local_identity(s_compare->current_sender_address, s_compare->tblock);
1301
1302 if (!(new_sender_address = deliver_get_sender_address(message_id)))
1303 return 0;
1304
1305 message_local_identity =
1306 smtp_local_identity(new_sender_address, s_compare->tblock);
1307
1308 return Ustrcmp(current_local_identity, message_local_identity) == 0;
1309 }
1310
1311
1312
1313 uschar
1314 ehlo_response(uschar * buf, size_t bsize, uschar checks)
1315 {
1316 #ifdef SUPPORT_TLS
1317 if ( checks & PEER_OFFERED_TLS
1318 && pcre_exec(regex_STARTTLS, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1319 checks &= ~PEER_OFFERED_TLS;
1320 #endif
1321
1322 if ( checks & PEER_OFFERED_IGNQ
1323 && pcre_exec(regex_IGNOREQUOTA, NULL, CS buf, bsize, 0,
1324 PCRE_EOPT, NULL, 0) < 0)
1325 checks &= ~PEER_OFFERED_IGNQ;
1326
1327 if ( checks & PEER_OFFERED_CHUNKING
1328 && pcre_exec(regex_CHUNKING, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1329 checks &= ~PEER_OFFERED_CHUNKING;
1330
1331 #ifndef DISABLE_PRDR
1332 if ( checks & PEER_OFFERED_PRDR
1333 && pcre_exec(regex_PRDR, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1334 checks &= ~PEER_OFFERED_PRDR;
1335 #endif
1336
1337 #ifdef SUPPORT_I18N
1338 if ( checks & PEER_OFFERED_UTF8
1339 && pcre_exec(regex_UTF8, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1340 checks &= ~PEER_OFFERED_UTF8;
1341 #endif
1342
1343 if ( checks & PEER_OFFERED_DSN
1344 && pcre_exec(regex_DSN, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1345 checks &= ~PEER_OFFERED_DSN;
1346
1347 if ( checks & PEER_OFFERED_PIPE
1348 && pcre_exec(regex_PIPELINING, NULL, CS buf, bsize, 0,
1349 PCRE_EOPT, NULL, 0) < 0)
1350 checks &= ~PEER_OFFERED_PIPE;
1351
1352 if ( checks & PEER_OFFERED_SIZE
1353 && pcre_exec(regex_SIZE, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1354 checks &= ~PEER_OFFERED_SIZE;
1355
1356 return checks;
1357 }
1358
1359
1360
1361 /* Callback for emitting a BDAT data chunk header.
1362
1363 If given a nonzero size, first flush any buffered SMTP commands
1364 then emit the command.
1365
1366 Reap previous SMTP command responses if requested.
1367 Reap one SMTP command response if requested.
1368
1369 Returns: OK or ERROR
1370 */
1371
1372 static int
1373 smtp_chunk_cmd_callback(int fd, transport_ctx * tctx,
1374 unsigned chunk_size, unsigned flags)
1375 {
1376 smtp_transport_options_block * ob =
1377 (smtp_transport_options_block *)(tctx->tblock->options_block);
1378 int cmd_count = 0;
1379 int prev_cmd_count;
1380 uschar * buffer = tctx->buffer;
1381
1382
1383 /* Write SMTP chunk header command */
1384
1385 if (chunk_size > 0)
1386 if((cmd_count = smtp_write_command(tctx->outblock, FALSE, "BDAT %u%s\r\n",
1387 chunk_size,
1388 flags & tc_chunk_last ? " LAST" : "")
1389 ) < 0) return ERROR;
1390
1391 prev_cmd_count = cmd_count += tctx->cmd_count;
1392
1393 /* Reap responses for any previous, but not one we just emitted */
1394
1395 if (chunk_size > 0)
1396 prev_cmd_count--;
1397 if (tctx->pending_BDAT)
1398 prev_cmd_count--;
1399
1400 if (flags & tc_reap_prev && prev_cmd_count > 0)
1401 {
1402
1403 switch(sync_responses(tctx->first_addr, tctx->tblock->rcpt_include_affixes,
1404 tctx->sync_addr, tctx->host, prev_cmd_count,
1405 ob->address_retry_include_sender,
1406 tctx->pending_MAIL, 0,
1407 tctx->inblock,
1408 ob->command_timeout,
1409 buffer, 4096))
1410 /*XXX buffer size! */
1411 {
1412 case 1: /* 2xx (only) => OK */
1413 case 3: tctx->good_RCPT = TRUE; /* 2xx & 5xx => OK & progress made */
1414 case 2: *tctx->completed_address = TRUE; /* 5xx (only) => progress made */
1415 case 0: break; /* No 2xx or 5xx, but no probs */
1416
1417 case -1: /* Timeout on RCPT */
1418 default: return ERROR; /* I/O error, or any MAIL/DATA error */
1419 }
1420 cmd_count = 1;
1421 if (!tctx->pending_BDAT)
1422 pipelining_active = FALSE;
1423 }
1424
1425 /* Reap response for the cmd we just emitted, or an outstanding BDAT */
1426
1427 if (flags & tc_reap_one || tctx->pending_BDAT)
1428 {
1429 /*XXX buffer size! */
1430 if (!smtp_read_response(tctx->inblock, buffer, 4096, '2',
1431 ob->command_timeout))
1432 {
1433 if (errno == 0 && buffer[0] == '4')
1434 {
1435 errno = ERRNO_DATA4XX; /*XXX does this actually get used? */
1436 tctx->first_addr->more_errno |=
1437 ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1438 }
1439 return ERROR;
1440 }
1441 cmd_count--;
1442 tctx->pending_BDAT = FALSE;
1443 pipelining_active = FALSE;
1444 }
1445 else if (chunk_size > 0)
1446 tctx->pending_BDAT = TRUE;
1447
1448
1449 tctx->cmd_count = cmd_count;
1450 return OK;
1451 }
1452
1453
1454
1455 /*************************************************
1456 * Deliver address list to given host *
1457 *************************************************/
1458
1459 /* If continue_hostname is not null, we get here only when continuing to
1460 deliver down an existing channel. The channel was passed as the standard
1461 input. TLS is never active on a passed channel; the previous process always
1462 closes it down before passing the connection on.
1463
1464 Otherwise, we have to make a connection to the remote host, and do the
1465 initial protocol exchange.
1466
1467 When running as an MUA wrapper, if the sender or any recipient is rejected,
1468 temporarily or permanently, we force failure for all recipients.
1469
1470 Arguments:
1471 addrlist chain of potential addresses to deliver; only those whose
1472 transport_return field is set to PENDING_DEFER are currently
1473 being processed; others should be skipped - they have either
1474 been delivered to an earlier host or IP address, or been
1475 failed by one of them.
1476 host host to deliver to
1477 host_af AF_INET or AF_INET6
1478 port default TCP/IP port to use, in host byte order
1479 interface interface to bind to, or NULL
1480 tblock transport instance block
1481 message_defer set TRUE if yield is OK, but all addresses were deferred
1482 because of a non-recipient, non-host failure, that is, a
1483 4xx response to MAIL FROM, DATA, or ".". This is a defer
1484 that is specific to the message.
1485 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1486 a second attempt after TLS initialization fails
1487
1488 Returns: OK - the connection was made and the delivery attempted;
1489 the result for each address is in its data block.
1490 DEFER - the connection could not be made, or something failed
1491 while setting up the SMTP session, or there was a
1492 non-message-specific error, such as a timeout.
1493 ERROR - a filter command is specified for this transport,
1494 and there was a problem setting it up; OR helo_data
1495 or add_headers or authenticated_sender is specified
1496 for this transport, and the string failed to expand
1497 */
1498
1499 static int
1500 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
1501 uschar *interface, transport_instance *tblock,
1502 BOOL *message_defer, BOOL suppress_tls)
1503 {
1504 address_item *addr;
1505 address_item *sync_addr;
1506 address_item *first_addr = addrlist;
1507 int yield = OK;
1508 int address_count;
1509 int save_errno;
1510 int rc;
1511 time_t start_delivery_time = time(NULL);
1512 smtp_transport_options_block *ob =
1513 (smtp_transport_options_block *)(tblock->options_block);
1514 BOOL lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
1515 BOOL smtps = strcmpic(ob->protocol, US"smtps") == 0;
1516 BOOL ok = FALSE;
1517 BOOL send_rset = TRUE;
1518 BOOL send_quit = TRUE;
1519 BOOL setting_up = TRUE;
1520 BOOL completed_address = FALSE;
1521 BOOL esmtp = TRUE;
1522 BOOL pending_MAIL;
1523 BOOL pass_message = FALSE;
1524 uschar peer_offered = 0; /*XXX should this be handed on cf. tls_offered, smtp_use_dsn ? */
1525 #ifndef DISABLE_PRDR
1526 BOOL prdr_active;
1527 #endif
1528 #ifdef SUPPORT_I18N
1529 BOOL utf8_needed = FALSE;
1530 #endif
1531 BOOL dsn_all_lasthop = TRUE;
1532 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1533 BOOL dane = FALSE;
1534 BOOL dane_required = verify_check_given_host(&ob->hosts_require_dane, host) == OK;
1535 dns_answer tlsa_dnsa;
1536 #endif
1537 smtp_inblock inblock;
1538 smtp_outblock outblock;
1539 int max_rcpt = tblock->max_addresses;
1540 uschar *igquotstr = US"";
1541
1542 #ifdef EXPERIMENTAL_DSN_INFO
1543 uschar *smtp_greeting = NULL;
1544 uschar *helo_response = NULL;
1545 #endif
1546 uschar *helo_data = NULL;
1547
1548 uschar *message = NULL;
1549 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
1550 uschar *p;
1551 uschar buffer[4096];
1552 uschar inbuffer[4096];
1553 uschar outbuffer[4096];
1554
1555 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
1556
1557 *message_defer = FALSE;
1558 smtp_command = US"initial connection";
1559 if (max_rcpt == 0) max_rcpt = 999999;
1560
1561 /* Set up the buffer for reading SMTP response packets. */
1562
1563 inblock.buffer = inbuffer;
1564 inblock.buffersize = sizeof(inbuffer);
1565 inblock.ptr = inbuffer;
1566 inblock.ptrend = inbuffer;
1567
1568 /* Set up the buffer for holding SMTP commands while pipelining */
1569
1570 outblock.buffer = outbuffer;
1571 outblock.buffersize = sizeof(outbuffer);
1572 outblock.ptr = outbuffer;
1573 outblock.cmd_count = 0;
1574 outblock.authenticating = FALSE;
1575
1576 /* Reset the parameters of a TLS session. */
1577
1578 tls_out.bits = 0;
1579 tls_out.cipher = NULL; /* the one we may use for this transport */
1580 tls_out.ourcert = NULL;
1581 tls_out.peercert = NULL;
1582 tls_out.peerdn = NULL;
1583 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1584 tls_out.sni = NULL;
1585 #endif
1586 tls_out.ocsp = OCSP_NOT_REQ;
1587
1588 /* Flip the legacy TLS-related variables over to the outbound set in case
1589 they're used in the context of the transport. Don't bother resetting
1590 afterward as we're in a subprocess. */
1591
1592 tls_modify_variables(&tls_out);
1593
1594 #ifndef SUPPORT_TLS
1595 if (smtps)
1596 {
1597 set_errno_nohost(addrlist, ERRNO_TLSFAILURE, US"TLS support not available",
1598 DEFER, FALSE);
1599 return ERROR;
1600 }
1601 #endif
1602
1603 /* Make a connection to the host if this isn't a continued delivery, and handle
1604 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
1605 specially so they can be identified for retries. */
1606
1607 if (continue_hostname == NULL)
1608 {
1609 /* This puts port into host->port */
1610 inblock.sock = outblock.sock =
1611 smtp_connect(host, host_af, port, interface, ob->connect_timeout, tblock);
1612
1613 if (inblock.sock < 0)
1614 {
1615 set_errno_nohost(addrlist, (errno == ETIMEDOUT)? ERRNO_CONNECTTIMEOUT : errno,
1616 NULL, DEFER, FALSE);
1617 return DEFER;
1618 }
1619
1620 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1621 {
1622 tls_out.dane_verified = FALSE;
1623 tls_out.tlsa_usage = 0;
1624
1625 if (host->dnssec == DS_YES)
1626 {
1627 if( dane_required
1628 || verify_check_given_host(&ob->hosts_try_dane, host) == OK
1629 )
1630 switch (rc = tlsa_lookup(host, &tlsa_dnsa, dane_required))
1631 {
1632 case OK: dane = TRUE; break;
1633 case FAIL_FORCED: break;
1634 default: set_errno_nohost(addrlist, ERRNO_DNSDEFER,
1635 string_sprintf("DANE error: tlsa lookup %s",
1636 rc == DEFER ? "DEFER" : "FAIL"),
1637 rc, FALSE);
1638 return rc;
1639 }
1640 }
1641 else if (dane_required)
1642 {
1643 set_errno_nohost(addrlist, ERRNO_DNSDEFER,
1644 string_sprintf("DANE error: %s lookup not DNSSEC", host->name),
1645 FAIL, FALSE);
1646 return FAIL;
1647 }
1648
1649 if (dane)
1650 ob->tls_tempfail_tryclear = FALSE;
1651 }
1652 #endif /*DANE*/
1653
1654 /* Expand the greeting message while waiting for the initial response. (Makes
1655 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1656 delayed till here so that $sending_interface and $sending_port are set. */
1657
1658 helo_data = expand_string(ob->helo_data);
1659 #ifdef SUPPORT_I18N
1660 if (helo_data)
1661 {
1662 uschar * errstr = NULL;
1663 if ((helo_data = string_domain_utf8_to_alabel(helo_data, &errstr)), errstr)
1664 {
1665 errstr = string_sprintf("failed to expand helo_data: %s", errstr);
1666 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE);
1667 yield = DEFER;
1668 goto SEND_QUIT;
1669 }
1670 }
1671 #endif
1672
1673 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1674 is nevertheless a reasonably clean way of programming this kind of logic,
1675 where you want to escape on any error. */
1676
1677 if (!smtps)
1678 {
1679 BOOL good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
1680 '2', ob->command_timeout);
1681 #ifdef EXPERIMENTAL_DSN_INFO
1682 smtp_greeting = string_copy(buffer);
1683 #endif
1684 if (!good_response) goto RESPONSE_FAILED;
1685
1686 #ifndef DISABLE_EVENT
1687 {
1688 uschar * s;
1689 lookup_dnssec_authenticated = host->dnssec==DS_YES ? US"yes"
1690 : host->dnssec==DS_NO ? US"no" : NULL;
1691 s = event_raise(tblock->event_action, US"smtp:connect", buffer);
1692 if (s)
1693 {
1694 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL,
1695 string_sprintf("deferred by smtp:connect event expansion: %s", s),
1696 DEFER, FALSE);
1697 yield = DEFER;
1698 goto SEND_QUIT;
1699 }
1700 }
1701 #endif
1702
1703 /* Now check if the helo_data expansion went well, and sign off cleanly if
1704 it didn't. */
1705
1706 if (helo_data == NULL)
1707 {
1708 uschar *message = string_sprintf("failed to expand helo_data: %s",
1709 expand_string_message);
1710 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1711 yield = DEFER;
1712 goto SEND_QUIT;
1713 }
1714 }
1715
1716 /** Debugging without sending a message
1717 addrlist->transport_return = DEFER;
1718 goto SEND_QUIT;
1719 **/
1720
1721 /* Errors that occur after this point follow an SMTP command, which is
1722 left in big_buffer by smtp_write_command() for use in error messages. */
1723
1724 smtp_command = big_buffer;
1725
1726 /* Tell the remote who we are...
1727
1728 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1729 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1730 greeting is of this form. The assumption was that the far end supports it
1731 properly... but experience shows that there are some that give 5xx responses,
1732 even though the banner includes "ESMTP" (there's a bloody-minded one that
1733 says "ESMTP not spoken here"). Cope with that case.
1734
1735 September 2000: Time has passed, and it seems reasonable now to always send
1736 EHLO at the start. It is also convenient to make the change while installing
1737 the TLS stuff.
1738
1739 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1740 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1741 would be no way to send out the mails, so there is now a host list
1742 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1743 PIPELINING problem as well. Maybe it can also be useful to cure other
1744 problems with broken servers.
1745
1746 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1747 Then somebody tried it with a Microsoft mailer... It seems that all other
1748 mailers use upper case for some reason (the RFC is quite clear about case
1749 independence) so, for peace of mind, I gave in. */
1750
1751 esmtp = verify_check_given_host(&ob->hosts_avoid_esmtp, host) != OK;
1752
1753 /* Alas; be careful, since this goto is not an error-out, so conceivably
1754 we might set data between here and the target which we assume to exist
1755 and be usable. I can see this coming back to bite us. */
1756 #ifdef SUPPORT_TLS
1757 if (smtps)
1758 {
1759 tls_offered = TRUE;
1760 suppress_tls = FALSE;
1761 ob->tls_tempfail_tryclear = FALSE;
1762 smtp_command = US"SSL-on-connect";
1763 goto TLS_NEGOTIATE;
1764 }
1765 #endif
1766
1767 if (esmtp)
1768 {
1769 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1770 lmtp? "LHLO" : "EHLO", helo_data) < 0)
1771 goto SEND_FAILED;
1772 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1773 ob->command_timeout))
1774 {
1775 if (errno != 0 || buffer[0] == 0 || lmtp)
1776 {
1777 #ifdef EXPERIMENTAL_DSN_INFO
1778 helo_response = string_copy(buffer);
1779 #endif
1780 goto RESPONSE_FAILED;
1781 }
1782 esmtp = FALSE;
1783 }
1784 #ifdef EXPERIMENTAL_DSN_INFO
1785 helo_response = string_copy(buffer);
1786 #endif
1787 }
1788 else
1789 {
1790 DEBUG(D_transport)
1791 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1792 }
1793
1794 if (!esmtp)
1795 {
1796 BOOL good_response;
1797
1798 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1799 goto SEND_FAILED;
1800 good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
1801 '2', ob->command_timeout);
1802 #ifdef EXPERIMENTAL_DSN_INFO
1803 helo_response = string_copy(buffer);
1804 #endif
1805 if (!good_response) goto RESPONSE_FAILED;
1806 }
1807
1808 if (esmtp || lmtp)
1809 peer_offered = ehlo_response(buffer, Ustrlen(buffer),
1810 PEER_OFFERED_TLS /* others checked later */
1811 );
1812
1813 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1814
1815 #ifdef SUPPORT_TLS
1816 tls_offered = !!(peer_offered & PEER_OFFERED_TLS);
1817 #endif
1818 }
1819
1820 /* For continuing deliveries down the same channel, the socket is the standard
1821 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1822 below). Set up the pointer to where subsequent commands will be left, for
1823 error messages. Note that smtp_use_size and smtp_use_pipelining will have been
1824 set from the command line if they were set in the process that passed the
1825 connection on. */
1826
1827 /*XXX continue case needs to propagate DSN_INFO, prob. in deliver.c
1828 as the contine goes via transport_pass_socket() and doublefork and exec.
1829 It does not wait. Unclear how we keep separate host's responses
1830 separate - we could match up by host ip+port as a bodge. */
1831
1832 else
1833 {
1834 inblock.sock = outblock.sock = fileno(stdin);
1835 smtp_command = big_buffer;
1836 host->port = port; /* Record the port that was used */
1837 }
1838
1839 /* If TLS is available on this connection, whether continued or not, attempt to
1840 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1841 send another EHLO - the server may give a different answer in secure mode. We
1842 use a separate buffer for reading the response to STARTTLS so that if it is
1843 negative, the original EHLO data is available for subsequent analysis, should
1844 the client not be required to use TLS. If the response is bad, copy the buffer
1845 for error analysis. */
1846
1847 #ifdef SUPPORT_TLS
1848 if ( tls_offered
1849 && !suppress_tls
1850 && verify_check_given_host(&ob->hosts_avoid_tls, host) != OK)
1851 {
1852 uschar buffer2[4096];
1853 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1854 goto SEND_FAILED;
1855
1856 /* If there is an I/O error, transmission of this message is deferred. If
1857 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1858 false, we also defer. However, if there is a temporary rejection of STARTTLS
1859 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1860 STARTTLS, we carry on. This means we will try to send the message in clear,
1861 unless the host is in hosts_require_tls (tested below). */
1862
1863 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1864 ob->command_timeout))
1865 {
1866 if ( errno != 0
1867 || buffer2[0] == 0
1868 || (buffer2[0] == '4' && !ob->tls_tempfail_tryclear)
1869 )
1870 {
1871 Ustrncpy(buffer, buffer2, sizeof(buffer));
1872 goto RESPONSE_FAILED;
1873 }
1874 }
1875
1876 /* STARTTLS accepted: try to negotiate a TLS session. */
1877
1878 else
1879 TLS_NEGOTIATE:
1880 {
1881 int rc = tls_client_start(inblock.sock, host, addrlist, tblock
1882 # ifdef EXPERIMENTAL_DANE
1883 , dane ? &tlsa_dnsa : NULL
1884 # endif
1885 );
1886
1887 /* TLS negotiation failed; give an error. From outside, this function may
1888 be called again to try in clear on a new connection, if the options permit
1889 it for this host. */
1890
1891 if (rc != OK)
1892 {
1893 # ifdef EXPERIMENTAL_DANE
1894 if (rc == DEFER && dane)
1895 {
1896 log_write(0, LOG_MAIN,
1897 "DANE attempt failed; no TLS connection to %s [%s]",
1898 host->name, host->address);
1899 }
1900 # endif
1901
1902 save_errno = ERRNO_TLSFAILURE;
1903 message = US"failure while setting up TLS session";
1904 send_quit = FALSE;
1905 goto TLS_FAILED;
1906 }
1907
1908 /* TLS session is set up */
1909
1910 for (addr = addrlist; addr; addr = addr->next)
1911 if (addr->transport_return == PENDING_DEFER)
1912 {
1913 addr->cipher = tls_out.cipher;
1914 addr->ourcert = tls_out.ourcert;
1915 addr->peercert = tls_out.peercert;
1916 addr->peerdn = tls_out.peerdn;
1917 addr->ocsp = tls_out.ocsp;
1918 }
1919 }
1920 }
1921
1922 /* if smtps, we'll have smtp_command set to something else; always safe to
1923 reset it here. */
1924 smtp_command = big_buffer;
1925
1926 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1927 helo_data is null, we are dealing with a connection that was passed from
1928 another process, and so we won't have expanded helo_data above. We have to
1929 expand it here. $sending_ip_address and $sending_port are set up right at the
1930 start of the Exim process (in exim.c). */
1931
1932 if (tls_out.active >= 0)
1933 {
1934 char *greeting_cmd;
1935 BOOL good_response;
1936
1937 if (helo_data == NULL)
1938 {
1939 helo_data = expand_string(ob->helo_data);
1940 if (helo_data == NULL)
1941 {
1942 uschar *message = string_sprintf("failed to expand helo_data: %s",
1943 expand_string_message);
1944 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1945 yield = DEFER;
1946 goto SEND_QUIT;
1947 }
1948 }
1949
1950 /* For SMTPS we need to wait for the initial OK response. */
1951 if (smtps)
1952 {
1953 good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
1954 '2', ob->command_timeout);
1955 #ifdef EXPERIMENTAL_DSN_INFO
1956 smtp_greeting = string_copy(buffer);
1957 #endif
1958 if (!good_response) goto RESPONSE_FAILED;
1959 }
1960
1961 if (esmtp)
1962 greeting_cmd = "EHLO";
1963 else
1964 {
1965 greeting_cmd = "HELO";
1966 DEBUG(D_transport)
1967 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1968 }
1969
1970 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1971 lmtp? "LHLO" : greeting_cmd, helo_data) < 0)
1972 goto SEND_FAILED;
1973 good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
1974 '2', ob->command_timeout);
1975 #ifdef EXPERIMENTAL_DSN_INFO
1976 helo_response = string_copy(buffer);
1977 #endif
1978 if (!good_response) goto RESPONSE_FAILED;
1979 }
1980
1981 /* If the host is required to use a secure channel, ensure that we
1982 have one. */
1983
1984 else if ( smtps
1985 # ifdef EXPERIMENTAL_DANE
1986 || dane
1987 # endif
1988 || verify_check_given_host(&ob->hosts_require_tls, host) == OK
1989 )
1990 {
1991 save_errno = ERRNO_TLSREQUIRED;
1992 message = string_sprintf("a TLS session is required, but %s",
1993 tls_offered ? "an attempt to start TLS failed"
1994 : "the server did not offer TLS support");
1995 goto TLS_FAILED;
1996 }
1997 #endif /*SUPPORT_TLS*/
1998
1999 /* If TLS is active, we have just started it up and re-done the EHLO command,
2000 so its response needs to be analyzed. If TLS is not active and this is a
2001 continued session down a previously-used socket, we haven't just done EHLO, so
2002 we skip this. */
2003
2004 if (continue_hostname == NULL
2005 #ifdef SUPPORT_TLS
2006 || tls_out.active >= 0
2007 #endif
2008 )
2009 {
2010 if (esmtp || lmtp)
2011 peer_offered = ehlo_response(buffer, Ustrlen(buffer),
2012 0 /* no TLS */
2013 | (lmtp && ob->lmtp_ignore_quota ? PEER_OFFERED_IGNQ : 0)
2014 | PEER_OFFERED_CHUNKING
2015 | PEER_OFFERED_PRDR
2016 #ifdef SUPPORT_I18N
2017 | (addrlist->prop.utf8_msg ? PEER_OFFERED_UTF8 : 0)
2018 /*XXX if we hand peercaps on to continued-conn processes,
2019 must not depend on this addr */
2020 #endif
2021 | PEER_OFFERED_DSN
2022 | PEER_OFFERED_PIPE
2023 | (ob->size_addition >= 0 ? PEER_OFFERED_SIZE : 0)
2024 );
2025
2026 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
2027 lmtp_ignore_quota option was set. */
2028
2029 igquotstr = peer_offered & PEER_OFFERED_IGNQ ? US" IGNOREQUOTA" : US"";
2030
2031 /* If the response to EHLO specified support for the SIZE parameter, note
2032 this, provided size_addition is non-negative. */
2033
2034 smtp_use_size = !!(peer_offered & PEER_OFFERED_SIZE);
2035
2036 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
2037 the current host, esmtp will be false, so PIPELINING can never be used. If
2038 the current host matches hosts_avoid_pipelining, don't do it. */
2039
2040 smtp_use_pipelining = peer_offered & PEER_OFFERED_PIPE
2041 && verify_check_given_host(&ob->hosts_avoid_pipelining, host) != OK;
2042
2043 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
2044 smtp_use_pipelining ? "" : "not ");
2045
2046 if ( peer_offered & PEER_OFFERED_CHUNKING
2047 && verify_check_given_host(&ob->hosts_try_chunking, host) != OK)
2048 peer_offered &= ~PEER_OFFERED_CHUNKING;
2049
2050 if (peer_offered & PEER_OFFERED_CHUNKING)
2051 {DEBUG(D_transport) debug_printf("CHUNKING usable\n");}
2052
2053 #ifndef DISABLE_PRDR
2054 if ( peer_offered & PEER_OFFERED_PRDR
2055 && verify_check_given_host(&ob->hosts_try_prdr, host) != OK)
2056 peer_offered &= ~PEER_OFFERED_PRDR;
2057
2058 if (peer_offered & PEER_OFFERED_PRDR)
2059 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
2060 #endif
2061
2062 /* Note if the server supports DSN */
2063 smtp_use_dsn = !!(peer_offered & PEER_OFFERED_DSN);
2064 DEBUG(D_transport) debug_printf("%susing DSN\n", smtp_use_dsn ? "" : "not ");
2065
2066 /* Note if the response to EHLO specifies support for the AUTH extension.
2067 If it has, check that this host is one we want to authenticate to, and do
2068 the business. The host name and address must be available when the
2069 authenticator's client driver is running. */
2070
2071 switch (yield = smtp_auth(buffer, sizeof(buffer), addrlist, host,
2072 ob, esmtp, &inblock, &outblock))
2073 {
2074 default: goto SEND_QUIT;
2075 case OK: break;
2076 case FAIL_SEND: goto SEND_FAILED;
2077 case FAIL: goto RESPONSE_FAILED;
2078 }
2079 }
2080 pipelining_active = smtp_use_pipelining;
2081
2082 /* The setting up of the SMTP call is now complete. Any subsequent errors are
2083 message-specific. */
2084
2085 setting_up = FALSE;
2086
2087 #ifdef SUPPORT_I18N
2088 if (addrlist->prop.utf8_msg)
2089 {
2090 utf8_needed = !addrlist->prop.utf8_downcvt
2091 && !addrlist->prop.utf8_downcvt_maybe;
2092 DEBUG(D_transport) if (!utf8_needed) debug_printf("utf8: %s downconvert\n",
2093 addrlist->prop.utf8_downcvt ? "mandatory" : "optional");
2094 }
2095
2096 /* If this is an international message we need the host to speak SMTPUTF8 */
2097 if (utf8_needed && !(peer_offered & PEER_OFFERED_UTF8))
2098 {
2099 errno = ERRNO_UTF8_FWD;
2100 goto RESPONSE_FAILED;
2101 }
2102 #endif
2103
2104 /* If there is a filter command specified for this transport, we can now
2105 set it up. This cannot be done until the identify of the host is known. */
2106
2107 if (tblock->filter_command != NULL)
2108 {
2109 BOOL rc;
2110 uschar buffer[64];
2111 sprintf(CS buffer, "%.50s transport", tblock->name);
2112 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
2113 TRUE, DEFER, addrlist, buffer, NULL);
2114 transport_filter_timeout = tblock->filter_timeout;
2115
2116 /* On failure, copy the error to all addresses, abandon the SMTP call, and
2117 yield ERROR. */
2118
2119 if (!rc)
2120 {
2121 set_errno_nohost(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
2122 FALSE);
2123 yield = ERROR;
2124 goto SEND_QUIT;
2125 }
2126
2127 if ( transport_filter_argv
2128 && *transport_filter_argv
2129 && **transport_filter_argv
2130 && peer_offered & PEER_OFFERED_CHUNKING
2131 )
2132 {
2133 peer_offered &= ~PEER_OFFERED_CHUNKING;
2134 DEBUG(D_transport) debug_printf("CHUNKING not usable due to transport filter\n");
2135 }
2136 }
2137
2138
2139 /* For messages that have more than the maximum number of envelope recipients,
2140 we want to send several transactions down the same SMTP connection. (See
2141 comments in deliver.c as to how this reconciles, heuristically, with
2142 remote_max_parallel.) This optimization was added to Exim after the following
2143 code was already working. The simplest way to put it in without disturbing the
2144 code was to use a goto to jump back to this point when there is another
2145 transaction to handle. */
2146
2147 SEND_MESSAGE:
2148 sync_addr = first_addr;
2149 address_count = 0;
2150 ok = FALSE;
2151 send_rset = TRUE;
2152 completed_address = FALSE;
2153
2154
2155 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
2156 qualification, send it, adding something to the message size to allow for
2157 imprecision and things that get added en route. Exim keeps the number of lines
2158 in a message, so we can give an accurate value for the original message, but we
2159 need some additional to handle added headers. (Double "." characters don't get
2160 included in the count.) */
2161
2162 p = buffer;
2163 *p = 0;
2164
2165 if (smtp_use_size)
2166 {
2167 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
2168 while (*p) p++;
2169 }
2170
2171 #ifndef DISABLE_PRDR
2172 prdr_active = FALSE;
2173 if (peer_offered & PEER_OFFERED_PRDR)
2174 for (addr = first_addr; addr; addr = addr->next)
2175 if (addr->transport_return == PENDING_DEFER)
2176 {
2177 for (addr = addr->next; addr; addr = addr->next)
2178 if (addr->transport_return == PENDING_DEFER)
2179 { /* at least two recipients to send */
2180 prdr_active = TRUE;
2181 sprintf(CS p, " PRDR"); p += 5;
2182 break;
2183 }
2184 break;
2185 }
2186 #endif
2187
2188 #ifdef SUPPORT_I18N
2189 if ( addrlist->prop.utf8_msg
2190 && !addrlist->prop.utf8_downcvt
2191 && peer_offered & PEER_OFFERED_UTF8
2192 )
2193 sprintf(CS p, " SMTPUTF8"), p += 9;
2194 #endif
2195
2196 /* check if all addresses have lasthop flag */
2197 /* do not send RET and ENVID if true */
2198 for (dsn_all_lasthop = TRUE, addr = first_addr;
2199 address_count < max_rcpt && addr != NULL;
2200 addr = addr->next)
2201 if ((addr->dsn_flags & rf_dsnlasthop) != 1)
2202 {
2203 dsn_all_lasthop = FALSE;
2204 break;
2205 }
2206
2207 /* Add any DSN flags to the mail command */
2208
2209 if (smtp_use_dsn && !dsn_all_lasthop)
2210 {
2211 if (dsn_ret == dsn_ret_hdrs)
2212 { Ustrcpy(p, " RET=HDRS"); p += 9; }
2213 else if (dsn_ret == dsn_ret_full)
2214 { Ustrcpy(p, " RET=FULL"); p += 9; }
2215
2216 if (dsn_envid)
2217 {
2218 string_format(p, sizeof(buffer) - (p-buffer), " ENVID=%s", dsn_envid);
2219 while (*p) p++;
2220 }
2221 }
2222
2223 /* If an authenticated_sender override has been specified for this transport
2224 instance, expand it. If the expansion is forced to fail, and there was already
2225 an authenticated_sender for this message, the original value will be used.
2226 Other expansion failures are serious. An empty result is ignored, but there is
2227 otherwise no check - this feature is expected to be used with LMTP and other
2228 cases where non-standard addresses (e.g. without domains) might be required. */
2229
2230 if (smtp_mail_auth_str(p, sizeof(buffer) - (p-buffer), addrlist, ob))
2231 {
2232 yield = ERROR;
2233 goto SEND_QUIT;
2234 }
2235
2236 /* From here until we send the DATA command, we can make use of PIPELINING
2237 if the server host supports it. The code has to be able to check the responses
2238 at any point, for when the buffer fills up, so we write it totally generally.
2239 When PIPELINING is off, each command written reports that it has flushed the
2240 buffer. */
2241
2242 pending_MAIL = TRUE; /* The block starts with MAIL */
2243
2244 {
2245 uschar * s = return_path;
2246 #ifdef SUPPORT_I18N
2247 uschar * errstr = NULL;
2248
2249 /* If we must downconvert, do the from-address here. Remember we had to
2250 for the to-addresses (done below), and also (ugly) for re-doing when building
2251 the delivery log line. */
2252
2253 if ( addrlist->prop.utf8_msg
2254 && (addrlist->prop.utf8_downcvt || !(peer_offered & PEER_OFFERED_UTF8))
2255 )
2256 {
2257 if (s = string_address_utf8_to_alabel(return_path, &errstr), errstr)
2258 {
2259 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE);
2260 yield = ERROR;
2261 goto SEND_QUIT;
2262 }
2263 setflag(addrlist, af_utf8_downcvt);
2264 }
2265 #endif
2266
2267 rc = smtp_write_command(&outblock, smtp_use_pipelining,
2268 "MAIL FROM:<%s>%s\r\n", s, buffer);
2269 }
2270
2271 mail_command = string_copy(big_buffer); /* Save for later error message */
2272
2273 switch(rc)
2274 {
2275 case -1: /* Transmission error */
2276 goto SEND_FAILED;
2277
2278 case +1: /* Block was sent */
2279 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2280 ob->command_timeout))
2281 {
2282 if (errno == 0 && buffer[0] == '4')
2283 {
2284 errno = ERRNO_MAIL4XX;
2285 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2286 }
2287 goto RESPONSE_FAILED;
2288 }
2289 pending_MAIL = FALSE;
2290 break;
2291 }
2292
2293 /* Pass over all the relevant recipient addresses for this host, which are the
2294 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
2295 several before we have to read the responses for those seen so far. This
2296 checking is done by a subroutine because it also needs to be done at the end.
2297 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
2298 the next one if not all are sent.
2299
2300 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
2301 last address because we want to abort if any recipients have any kind of
2302 problem, temporary or permanent. We know that all recipient addresses will have
2303 the PENDING_DEFER status, because only one attempt is ever made, and we know
2304 that max_rcpt will be large, so all addresses will be done at once. */
2305
2306 for (addr = first_addr;
2307 addr && address_count < max_rcpt;
2308 addr = addr->next)
2309 {
2310 int count;
2311 BOOL no_flush;
2312 uschar * rcpt_addr;
2313
2314 addr->dsn_aware = smtp_use_dsn ? dsn_support_yes : dsn_support_no;
2315
2316 if (addr->transport_return != PENDING_DEFER) continue;
2317
2318 address_count++;
2319 no_flush = smtp_use_pipelining && (!mua_wrapper || addr->next);
2320
2321 /* Add any DSN flags to the rcpt command and add to the sent string */
2322
2323 p = buffer;
2324 *p = 0;
2325
2326 if (smtp_use_dsn && !(addr->dsn_flags & rf_dsnlasthop))
2327 {
2328 if ((addr->dsn_flags & rf_dsnflags) != 0)
2329 {
2330 int i;
2331 BOOL first = TRUE;
2332 Ustrcpy(p, " NOTIFY=");
2333 while (*p) p++;
2334 for (i = 0; i < 4; i++)
2335 if ((addr->dsn_flags & rf_list[i]) != 0)
2336 {
2337 if (!first) *p++ = ',';
2338 first = FALSE;
2339 Ustrcpy(p, rf_names[i]);
2340 while (*p) p++;
2341 }
2342 }
2343
2344 if (addr->dsn_orcpt)
2345 {
2346 string_format(p, sizeof(buffer) - (p-buffer), " ORCPT=%s",
2347 addr->dsn_orcpt);
2348 while (*p) p++;
2349 }
2350 }
2351
2352 /* Now send the RCPT command, and process outstanding responses when
2353 necessary. After a timeout on RCPT, we just end the function, leaving the
2354 yield as OK, because this error can often mean that there is a problem with
2355 just one address, so we don't want to delay the host. */
2356
2357 rcpt_addr = transport_rcpt_address(addr, tblock->rcpt_include_affixes);
2358
2359 #ifdef SUPPORT_I18N
2360 {
2361 uschar * dummy_errstr;
2362 if ( testflag(addrlist, af_utf8_downcvt)
2363 && (rcpt_addr = string_address_utf8_to_alabel(rcpt_addr, &dummy_errstr),
2364 dummy_errstr
2365 ) )
2366 {
2367 errno = ERRNO_EXPANDFAIL;
2368 goto SEND_FAILED;
2369 }
2370 }
2371 #endif
2372
2373 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s%s\r\n",
2374 rcpt_addr, igquotstr, buffer);
2375
2376 if (count < 0) goto SEND_FAILED;
2377 if (count > 0)
2378 {
2379 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
2380 &sync_addr, host, count, ob->address_retry_include_sender,
2381 pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
2382 sizeof(buffer)))
2383 {
2384 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2385 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2386 break;
2387
2388 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2389 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2390 case 0: /* No 2xx or 5xx, but no probs */
2391 break;
2392
2393 case -1: goto END_OFF; /* Timeout on RCPT */
2394 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
2395 }
2396 pending_MAIL = FALSE; /* Dealt with MAIL */
2397 }
2398 } /* Loop for next address */
2399
2400 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
2401 permanently or temporarily. We should have flushed and synced after the last
2402 RCPT. */
2403
2404 if (mua_wrapper)
2405 {
2406 address_item *badaddr;
2407 for (badaddr = first_addr; badaddr; badaddr = badaddr->next)
2408 if (badaddr->transport_return != PENDING_OK)
2409 {
2410 /*XXX could we find a better errno than 0 here? */
2411 set_errno_nohost(addrlist, 0, badaddr->message, FAIL,
2412 testflag(badaddr, af_pass_message));
2413 ok = FALSE;
2414 break;
2415 }
2416 }
2417
2418 /* If ok is TRUE, we know we have got at least one good recipient, and must now
2419 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
2420 have a good recipient buffered up if we are pipelining. We don't want to waste
2421 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
2422 are pipelining. The responses are all handled by sync_responses().
2423 If using CHUNKING, do not send a BDAT until we know how big a chunk we want
2424 to send is. */
2425
2426 if ( !(peer_offered & PEER_OFFERED_CHUNKING)
2427 && (ok || (smtp_use_pipelining && !mua_wrapper)))
2428 {
2429 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
2430
2431 if (count < 0) goto SEND_FAILED;
2432 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
2433 host, count, ob->address_retry_include_sender, pending_MAIL,
2434 ok ? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
2435 {
2436 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2437 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2438 break;
2439
2440 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2441 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2442 case 0: break; /* No 2xx or 5xx, but no probs */
2443
2444 case -1: goto END_OFF; /* Timeout on RCPT */
2445 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2446 }
2447 pipelining_active = FALSE;
2448 }
2449
2450 /* If there were no good recipients (but otherwise there have been no
2451 problems), just set ok TRUE, since we have handled address-specific errors
2452 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
2453 for handling the SMTP dot-handling protocol, flagging to apply to headers as
2454 well as body. Set the appropriate timeout value to be used for each chunk.
2455 (Haven't been able to make it work using select() for writing yet.) */
2456
2457 if (!(peer_offered & PEER_OFFERED_CHUNKING) && !ok)
2458 {
2459 /* Save the first address of the next batch. */
2460 first_addr = addr;
2461
2462 ok = TRUE;
2463 }
2464 else
2465 {
2466 transport_ctx tctx = {
2467 tblock,
2468 addrlist,
2469 US".", US"..", /* Escaping strings */
2470 topt_use_crlf | topt_escape_headers
2471 | (tblock->body_only ? topt_no_headers : 0)
2472 | (tblock->headers_only ? topt_no_body : 0)
2473 | (tblock->return_path_add ? topt_add_return_path : 0)
2474 | (tblock->delivery_date_add ? topt_add_delivery_date : 0)
2475 | (tblock->envelope_to_add ? topt_add_envelope_to : 0),
2476 };
2477
2478 /* If using CHUNKING we need a callback from the generic transport
2479 support to us, for the sending of BDAT smtp commands and the reaping
2480 of responses. The callback needs a whole bunch of state so set up
2481 a transport-context structure to be passed around. */
2482
2483 if (peer_offered & PEER_OFFERED_CHUNKING)
2484 {
2485 tctx.check_string = tctx.escape_string = NULL;
2486 tctx.options |= topt_use_bdat;
2487 tctx.chunk_cb = smtp_chunk_cmd_callback;
2488 tctx.inblock = &inblock;
2489 tctx.outblock = &outblock;
2490 tctx.host = host;
2491 tctx.first_addr = first_addr;
2492 tctx.sync_addr = &sync_addr;
2493 tctx.pending_MAIL = pending_MAIL;
2494 tctx.pending_BDAT = FALSE;
2495 tctx.good_RCPT = ok;
2496 tctx.completed_address = &completed_address;
2497 tctx.cmd_count = 0;
2498 tctx.buffer = buffer;
2499 }
2500 else
2501 tctx.options |= topt_end_dot;
2502
2503 /* Save the first address of the next batch. */
2504 first_addr = addr;
2505
2506 /* Responses from CHUNKING commands go in buffer. Otherwise,
2507 there has not been a response. */
2508
2509 buffer[0] = 0;
2510
2511 sigalrm_seen = FALSE;
2512 transport_write_timeout = ob->data_timeout;
2513 smtp_command = US"sending data block"; /* For error messages */
2514 DEBUG(D_transport|D_v)
2515 if (peer_offered & PEER_OFFERED_CHUNKING)
2516 debug_printf(" will write message using CHUNKING\n");
2517 else
2518 debug_printf(" SMTP>> writing message and terminating \".\"\n");
2519 transport_count = 0;
2520
2521 #ifndef DISABLE_DKIM
2522 ok = dkim_transport_write_message(inblock.sock, &tctx, &ob->dkim);
2523 #else
2524 ok = transport_write_message(inblock.sock, &tctx, 0);
2525 #endif
2526
2527 /* transport_write_message() uses write() because it is called from other
2528 places to write to non-sockets. This means that under some OS (e.g. Solaris)
2529 it can exit with "Broken pipe" as its error. This really means that the
2530 socket got closed at the far end. */
2531
2532 transport_write_timeout = 0; /* for subsequent transports */
2533
2534 /* Failure can either be some kind of I/O disaster (including timeout),
2535 or the failure of a transport filter or the expansion of added headers.
2536 Or, when CHUNKING, it can be a protocol-detected failure. */
2537
2538 if (!ok)
2539 goto RESPONSE_FAILED;
2540
2541 /* We used to send the terminating "." explicitly here, but because of
2542 buffering effects at both ends of TCP/IP connections, you don't gain
2543 anything by keeping it separate, so it might as well go in the final
2544 data buffer for efficiency. This is now done by setting the topt_end_dot
2545 flag above. */
2546
2547 smtp_command = US"end of data";
2548
2549 if (peer_offered & PEER_OFFERED_CHUNKING && tctx.cmd_count > 1)
2550 {
2551 /* Reap any outstanding MAIL & RCPT commands, but not a DATA-go-ahead */
2552 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
2553 host, tctx.cmd_count-1, ob->address_retry_include_sender,
2554 pending_MAIL, 0,
2555 &inblock, ob->command_timeout, buffer, sizeof(buffer)))
2556 {
2557 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2558 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2559 break;
2560
2561 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2562 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2563 case 0: break; /* No 2xx or 5xx, but no probs */
2564
2565 case -1: goto END_OFF; /* Timeout on RCPT */
2566 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2567 }
2568 }
2569
2570 #ifndef DISABLE_PRDR
2571 /* For PRDR we optionally get a partial-responses warning
2572 * followed by the individual responses, before going on with
2573 * the overall response. If we don't get the warning then deal
2574 * with per non-PRDR. */
2575 if(prdr_active)
2576 {
2577 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '3',
2578 ob->final_timeout);
2579 if (!ok && errno == 0) switch(buffer[0])
2580 {
2581 case '2': prdr_active = FALSE;
2582 ok = TRUE;
2583 break;
2584 case '4': errno = ERRNO_DATA4XX;
2585 addrlist->more_errno |=
2586 ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2587 break;
2588 }
2589 }
2590 else
2591 #endif
2592
2593 /* For non-PRDR SMTP, we now read a single response that applies to the
2594 whole message. If it is OK, then all the addresses have been delivered. */
2595
2596 if (!lmtp)
2597 {
2598 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2599 ob->final_timeout);
2600 if (!ok && errno == 0 && buffer[0] == '4')
2601 {
2602 errno = ERRNO_DATA4XX;
2603 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2604 }
2605 }
2606
2607 /* For LMTP, we get back a response for every RCPT command that we sent;
2608 some may be accepted and some rejected. For those that get a response, their
2609 status is fixed; any that are accepted have been handed over, even if later
2610 responses crash - at least, that's how I read RFC 2033.
2611
2612 If all went well, mark the recipient addresses as completed, record which
2613 host/IPaddress they were delivered to, and cut out RSET when sending another
2614 message down the same channel. Write the completed addresses to the journal
2615 now so that they are recorded in case there is a crash of hardware or
2616 software before the spool gets updated. Also record the final SMTP
2617 confirmation if needed (for SMTP only). */
2618
2619 if (ok)
2620 {
2621 int flag = '=';
2622 int delivery_time = (int)(time(NULL) - start_delivery_time);
2623 int len;
2624 uschar *conf = NULL;
2625
2626 send_rset = FALSE;
2627 pipelining_active = FALSE;
2628
2629 /* Set up confirmation if needed - applies only to SMTP */
2630
2631 if (
2632 #ifdef DISABLE_EVENT
2633 LOGGING(smtp_confirmation) &&
2634 #endif
2635 !lmtp
2636 )
2637 {
2638 const uschar *s = string_printing(buffer);
2639 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
2640 conf = (s == buffer)? (uschar *)string_copy(s) : US s;
2641 }
2642
2643 /* Process all transported addresses - for LMTP or PRDR, read a status for
2644 each one. */
2645
2646 for (addr = addrlist; addr != first_addr; addr = addr->next)
2647 {
2648 if (addr->transport_return != PENDING_OK) continue;
2649
2650 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
2651 remaining addresses. Otherwise, it's a return code for just the one
2652 address. For temporary errors, add a retry item for the address so that
2653 it doesn't get tried again too soon. */
2654
2655 #ifndef DISABLE_PRDR
2656 if (lmtp || prdr_active)
2657 #else
2658 if (lmtp)
2659 #endif
2660 {
2661 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2662 ob->final_timeout))
2663 {
2664 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
2665 addr->message = string_sprintf(
2666 #ifndef DISABLE_PRDR
2667 "%s error after %s: %s", prdr_active ? "PRDR":"LMTP",
2668 #else
2669 "LMTP error after %s: %s",
2670 #endif
2671 big_buffer, string_printing(buffer));
2672 setflag(addr, af_pass_message); /* Allow message to go to user */
2673 if (buffer[0] == '5')
2674 addr->transport_return = FAIL;
2675 else
2676 {
2677 errno = ERRNO_DATA4XX;
2678 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2679 addr->transport_return = DEFER;
2680 #ifndef DISABLE_PRDR
2681 if (!prdr_active)
2682 #endif
2683 retry_add_item(addr, addr->address_retry_key, 0);
2684 }
2685 continue;
2686 }
2687 completed_address = TRUE; /* NOW we can set this flag */
2688 if (LOGGING(smtp_confirmation))
2689 {
2690 const uschar *s = string_printing(buffer);
2691 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
2692 conf = (s == buffer)? (uschar *)string_copy(s) : US s;
2693 }
2694 }
2695
2696 /* SMTP, or success return from LMTP for this address. Pass back the
2697 actual host that was used. */
2698
2699 addr->transport_return = OK;
2700 addr->more_errno = delivery_time;
2701 addr->host_used = host;
2702 addr->special_action = flag;
2703 addr->message = conf;
2704 #ifndef DISABLE_PRDR
2705 if (prdr_active) addr->flags |= af_prdr_used;
2706 #endif
2707 if (peer_offered & PEER_OFFERED_CHUNKING) addr->flags |= af_chunking_used;
2708 flag = '-';
2709
2710 #ifndef DISABLE_PRDR
2711 if (!prdr_active)
2712 #endif
2713 {
2714 /* Update the journal. For homonymic addresses, use the base address plus
2715 the transport name. See lots of comments in deliver.c about the reasons
2716 for the complications when homonyms are involved. Just carry on after
2717 write error, as it may prove possible to update the spool file later. */
2718
2719 if (testflag(addr, af_homonym))
2720 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2721 else
2722 sprintf(CS buffer, "%.500s\n", addr->unique);
2723
2724 DEBUG(D_deliver) debug_printf("journalling %s\n", buffer);
2725 len = Ustrlen(CS buffer);
2726 if (write(journal_fd, buffer, len) != len)
2727 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2728 "%s: %s", buffer, strerror(errno));
2729 }
2730 }
2731
2732 #ifndef DISABLE_PRDR
2733 if (prdr_active)
2734 {
2735 /* PRDR - get the final, overall response. For any non-success
2736 upgrade all the address statuses. */
2737 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2738 ob->final_timeout);
2739 if (!ok)
2740 {
2741 if(errno == 0 && buffer[0] == '4')
2742 {
2743 errno = ERRNO_DATA4XX;
2744 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2745 }
2746 for (addr = addrlist; addr != first_addr; addr = addr->next)
2747 if (buffer[0] == '5' || addr->transport_return == OK)
2748 addr->transport_return = PENDING_OK; /* allow set_errno action */
2749 goto RESPONSE_FAILED;
2750 }
2751
2752 /* Update the journal, or setup retry. */
2753 for (addr = addrlist; addr != first_addr; addr = addr->next)
2754 if (addr->transport_return == OK)
2755 {
2756 if (testflag(addr, af_homonym))
2757 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2758 else
2759 sprintf(CS buffer, "%.500s\n", addr->unique);
2760
2761 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s\n", buffer);
2762 len = Ustrlen(CS buffer);
2763 if (write(journal_fd, buffer, len) != len)
2764 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2765 "%s: %s", buffer, strerror(errno));
2766 }
2767 else if (addr->transport_return == DEFER)
2768 retry_add_item(addr, addr->address_retry_key, -2);
2769 }
2770 #endif
2771
2772 /* Ensure the journal file is pushed out to disk. */
2773
2774 if (EXIMfsync(journal_fd) < 0)
2775 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
2776 strerror(errno));
2777 }
2778 }
2779
2780
2781 /* Handle general (not specific to one address) failures here. The value of ok
2782 is used to skip over this code on the falling through case. A timeout causes a
2783 deferral. Other errors may defer or fail according to the response code, and
2784 may set up a special errno value, e.g. after connection chopped, which is
2785 assumed if errno == 0 and there is no text in the buffer. If control reaches
2786 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
2787 the problem is not related to this specific message. */
2788
2789 if (!ok)
2790 {
2791 int code, set_rc;
2792 uschar * set_message;
2793
2794 RESPONSE_FAILED:
2795 {
2796 save_errno = errno;
2797 message = NULL;
2798 send_quit = check_response(host, &save_errno, addrlist->more_errno,
2799 buffer, &code, &message, &pass_message);
2800 goto FAILED;
2801 }
2802
2803 SEND_FAILED:
2804 {
2805 save_errno = errno;
2806 code = '4';
2807 message = US string_sprintf("send() to %s [%s] failed: %s",
2808 host->name, host->address, strerror(save_errno));
2809 send_quit = FALSE;
2810 goto FAILED;
2811 }
2812
2813 /* This label is jumped to directly when a TLS negotiation has failed,
2814 or was not done for a host for which it is required. Values will be set
2815 in message and save_errno, and setting_up will always be true. Treat as
2816 a temporary error. */
2817
2818 #ifdef SUPPORT_TLS
2819 TLS_FAILED:
2820 code = '4';
2821 #endif
2822
2823 /* If the failure happened while setting up the call, see if the failure was
2824 a 5xx response (this will either be on connection, or following HELO - a 5xx
2825 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
2826 never going to accept them. For other errors during setting up (timeouts or
2827 whatever), defer all addresses, and yield DEFER, so that the host is not
2828 tried again for a while. */
2829
2830 FAILED:
2831 ok = FALSE; /* For when reached by GOTO */
2832 set_message = message;
2833
2834 if (setting_up)
2835 {
2836 if (code == '5')
2837 set_rc = FAIL;
2838 else
2839 yield = set_rc = DEFER;
2840 }
2841
2842 /* We want to handle timeouts after MAIL or "." and loss of connection after
2843 "." specially. They can indicate a problem with the sender address or with
2844 the contents of the message rather than a real error on the connection. These
2845 cases are treated in the same way as a 4xx response. This next bit of code
2846 does the classification. */
2847
2848 else
2849 {
2850 BOOL message_error;
2851
2852 switch(save_errno)
2853 {
2854 #ifdef SUPPORT_I18N
2855 case ERRNO_UTF8_FWD:
2856 code = '5';
2857 /*FALLTHROUGH*/
2858 #endif
2859 case 0:
2860 case ERRNO_MAIL4XX:
2861 case ERRNO_DATA4XX:
2862 message_error = TRUE;
2863 break;
2864
2865 case ETIMEDOUT:
2866 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
2867 Ustrncmp(smtp_command,"end ",4) == 0;
2868 break;
2869
2870 case ERRNO_SMTPCLOSED:
2871 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
2872 break;
2873
2874 default:
2875 message_error = FALSE;
2876 break;
2877 }
2878
2879 /* Handle the cases that are treated as message errors. These are:
2880
2881 (a) negative response or timeout after MAIL
2882 (b) negative response after DATA
2883 (c) negative response or timeout or dropped connection after "."
2884 (d) utf8 support required and not offered
2885
2886 It won't be a negative response or timeout after RCPT, as that is dealt
2887 with separately above. The action in all cases is to set an appropriate
2888 error code for all the addresses, but to leave yield set to OK because the
2889 host itself has not failed. Of course, it might in practice have failed
2890 when we've had a timeout, but if so, we'll discover that at the next
2891 delivery attempt. For a temporary error, set the message_defer flag, and
2892 write to the logs for information if this is not the last host. The error
2893 for the last host will be logged as part of the address's log line. */
2894
2895 if (message_error)
2896 {
2897 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
2898
2899 /* If there's an errno, the message contains just the identity of
2900 the host. */
2901
2902 if (code == '5')
2903 set_rc = FAIL;
2904 else /* Anything other than 5 is treated as temporary */
2905 {
2906 set_rc = DEFER;
2907 if (save_errno > 0)
2908 message = US string_sprintf("%s: %s", message, strerror(save_errno));
2909 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
2910 msglog_line(host, message);
2911 *message_defer = TRUE;
2912 }
2913 }
2914
2915 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
2916 ".", or some other transportation error. We defer all addresses and yield
2917 DEFER, except for the case of failed add_headers expansion, or a transport
2918 filter failure, when the yield should be ERROR, to stop it trying other
2919 hosts. */
2920
2921 else
2922 {
2923 set_rc = DEFER;
2924 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
2925 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
2926 }
2927 }
2928
2929 set_errno(addrlist, save_errno, set_message, set_rc, pass_message, host
2930 #ifdef EXPERIMENTAL_DSN_INFO
2931 , smtp_greeting, helo_response
2932 #endif
2933 );
2934 }
2935
2936
2937 /* If all has gone well, send_quit will be set TRUE, implying we can end the
2938 SMTP session tidily. However, if there were too many addresses to send in one
2939 message (indicated by first_addr being non-NULL) we want to carry on with the
2940 rest of them. Also, it is desirable to send more than one message down the SMTP
2941 connection if there are several waiting, provided we haven't already sent so
2942 many as to hit the configured limit. The function transport_check_waiting looks
2943 for a waiting message and returns its id. Then transport_pass_socket tries to
2944 set up a continued delivery by passing the socket on to another process. The
2945 variable send_rset is FALSE if a message has just been successfully transfered.
2946
2947 If we are already sending down a continued channel, there may be further
2948 addresses not yet delivered that are aimed at the same host, but which have not
2949 been passed in this run of the transport. In this case, continue_more will be
2950 true, and all we should do is send RSET if necessary, and return, leaving the
2951 channel open.
2952
2953 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
2954 do not want to continue with other messages down the same channel, because that
2955 can lead to looping between two or more messages, all with the same,
2956 temporarily failing address(es). [The retry information isn't updated yet, so
2957 new processes keep on trying.] We probably also don't want to try more of this
2958 message's addresses either.
2959
2960 If we have started a TLS session, we have to end it before passing the
2961 connection to a new process. However, not all servers can handle this (Exim
2962 can), so we do not pass such a connection on if the host matches
2963 hosts_nopass_tls. */
2964
2965 DEBUG(D_transport)
2966 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
2967 "yield=%d first_address is %sNULL\n", ok, send_quit, send_rset,
2968 continue_more, yield, (first_addr == NULL)? "":"not ");
2969
2970 if (completed_address && ok && send_quit)
2971 {
2972 BOOL more;
2973 smtp_compare_t t_compare;
2974
2975 t_compare.tblock = tblock;
2976 t_compare.current_sender_address = sender_address;
2977
2978 if ( first_addr != NULL
2979 || continue_more
2980 || ( ( tls_out.active < 0
2981 || verify_check_given_host(&ob->hosts_nopass_tls, host) != OK
2982 )
2983 &&
2984 transport_check_waiting(tblock->name, host->name,
2985 tblock->connection_max_messages, new_message_id, &more,
2986 (oicf)smtp_are_same_identities, (void*)&t_compare)
2987 ) )
2988 {
2989 uschar *msg;
2990 BOOL pass_message;
2991
2992 if (send_rset)
2993 {
2994 if (! (ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
2995 {
2996 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
2997 host->address, strerror(save_errno));
2998 send_quit = FALSE;
2999 }
3000 else if (! (ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
3001 ob->command_timeout)))
3002 {
3003 int code;
3004 send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
3005 &pass_message);
3006 if (!send_quit)
3007 {
3008 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
3009 host->name, host->address, msg);
3010 }
3011 }
3012 }
3013
3014 /* Either RSET was not needed, or it succeeded */
3015
3016 if (ok)
3017 {
3018 if (first_addr != NULL) /* More addresses still to be sent */
3019 { /* in this run of the transport */
3020 continue_sequence++; /* Causes * in logging */
3021 goto SEND_MESSAGE;
3022 }
3023 if (continue_more) return yield; /* More addresses for another run */
3024
3025 /* Pass the socket to a new Exim process. Before doing so, we must shut
3026 down TLS. Not all MTAs allow for the continuation of the SMTP session
3027 when TLS is shut down. We test for this by sending a new EHLO. If we
3028 don't get a good response, we don't attempt to pass the socket on. */
3029
3030 #ifdef SUPPORT_TLS
3031 if (tls_out.active >= 0)
3032 {
3033 tls_close(FALSE, TRUE);
3034 if (smtps)
3035 ok = FALSE;
3036 else
3037 ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
3038 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
3039 ob->command_timeout);
3040 }
3041 #endif
3042
3043 /* If the socket is successfully passed, we musn't send QUIT (or
3044 indeed anything!) from here. */
3045
3046 /*XXX DSN_INFO: assume likely to do new HELO; but for greet we'll want to
3047 propagate it from the initial
3048 */
3049 if (ok && transport_pass_socket(tblock->name, host->name, host->address,
3050 new_message_id, inblock.sock))
3051 {
3052 send_quit = FALSE;
3053 }
3054 }
3055
3056 /* If RSET failed and there are addresses left, they get deferred. */
3057
3058 else set_errno(first_addr, errno, msg, DEFER, FALSE, host
3059 #ifdef EXPERIMENTAL_DSN_INFO
3060 , smtp_greeting, helo_response
3061 #endif
3062 );
3063 }
3064 }
3065
3066 /* End off tidily with QUIT unless the connection has died or the socket has
3067 been passed to another process. There has been discussion on the net about what
3068 to do after sending QUIT. The wording of the RFC suggests that it is necessary
3069 to wait for a response, but on the other hand, there isn't anything one can do
3070 with an error response, other than log it. Exim used to do that. However,
3071 further discussion suggested that it is positively advantageous not to wait for
3072 the response, but to close the session immediately. This is supposed to move
3073 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
3074 load from the server. (Hosts that are both servers and clients may not see much
3075 difference, of course.) Further discussion indicated that this was safe to do
3076 on Unix systems which have decent implementations of TCP/IP that leave the
3077 connection around for a while (TIME_WAIT) after the application has gone away.
3078 This enables the response sent by the server to be properly ACKed rather than
3079 timed out, as can happen on broken TCP/IP implementations on other OS.
3080
3081 This change is being made on 31-Jul-98. After over a year of trouble-free
3082 operation, the old commented-out code was removed on 17-Sep-99. */
3083
3084 SEND_QUIT:
3085 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
3086
3087 END_OFF:
3088
3089 #ifdef SUPPORT_TLS
3090 tls_close(FALSE, TRUE);
3091 #endif
3092
3093 /* Close the socket, and return the appropriate value, first setting
3094 works because the NULL setting is passed back to the calling process, and
3095 remote_max_parallel is forced to 1 when delivering over an existing connection,
3096
3097 If all went well and continue_more is set, we shouldn't actually get here if
3098 there are further addresses, as the return above will be taken. However,
3099 writing RSET might have failed, or there may be other addresses whose hosts are
3100 specified in the transports, and therefore not visible at top level, in which
3101 case continue_more won't get set. */
3102
3103 HDEBUG(D_transport|D_acl|D_v) debug_printf(" SMTP(close)>>\n");
3104 (void)close(inblock.sock);
3105
3106 #ifndef DISABLE_EVENT
3107 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
3108 #endif
3109
3110 continue_transport = NULL;
3111 continue_hostname = NULL;
3112 return yield;
3113 }
3114
3115
3116
3117
3118 /*************************************************
3119 * Closedown entry point *
3120 *************************************************/
3121
3122 /* This function is called when exim is passed an open smtp channel
3123 from another incarnation, but the message which it has been asked
3124 to deliver no longer exists. The channel is on stdin.
3125
3126 We might do fancy things like looking for another message to send down
3127 the channel, but if the one we sought has gone, it has probably been
3128 delivered by some other process that itself will seek further messages,
3129 so just close down our connection.
3130
3131 Argument: pointer to the transport instance block
3132 Returns: nothing
3133 */
3134
3135 void
3136 smtp_transport_closedown(transport_instance *tblock)
3137 {
3138 smtp_transport_options_block *ob =
3139 (smtp_transport_options_block *)(tblock->options_block);
3140 smtp_inblock inblock;
3141 smtp_outblock outblock;
3142 uschar buffer[256];
3143 uschar inbuffer[4096];
3144 uschar outbuffer[16];
3145
3146 inblock.sock = fileno(stdin);
3147 inblock.buffer = inbuffer;
3148 inblock.buffersize = sizeof(inbuffer);
3149 inblock.ptr = inbuffer;
3150 inblock.ptrend = inbuffer;
3151
3152 outblock.sock = inblock.sock;
3153 outblock.buffersize = sizeof(outbuffer);
3154 outblock.buffer = outbuffer;
3155 outblock.ptr = outbuffer;
3156 outblock.cmd_count = 0;
3157 outblock.authenticating = FALSE;
3158
3159 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
3160 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
3161 ob->command_timeout);
3162 (void)close(inblock.sock);
3163 }
3164
3165
3166
3167 /*************************************************
3168 * Prepare addresses for delivery *
3169 *************************************************/
3170
3171 /* This function is called to flush out error settings from previous delivery
3172 attempts to other hosts. It also records whether we got here via an MX record
3173 or not in the more_errno field of the address. We are interested only in
3174 addresses that are still marked DEFER - others may have got delivered to a
3175 previously considered IP address. Set their status to PENDING_DEFER to indicate
3176 which ones are relevant this time.
3177
3178 Arguments:
3179 addrlist the list of addresses
3180 host the host we are delivering to
3181
3182 Returns: the first address for this delivery
3183 */
3184
3185 static address_item *
3186 prepare_addresses(address_item *addrlist, host_item *host)
3187 {
3188 address_item *first_addr = NULL;
3189 address_item *addr;
3190 for (addr = addrlist; addr != NULL; addr = addr->next)
3191 if (addr->transport_return == DEFER)
3192 {
3193 if (first_addr == NULL) first_addr = addr;
3194 addr->transport_return = PENDING_DEFER;
3195 addr->basic_errno = 0;
3196 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
3197 addr->message = NULL;
3198 #ifdef SUPPORT_TLS
3199 addr->cipher = NULL;
3200 addr->ourcert = NULL;
3201 addr->peercert = NULL;
3202 addr->peerdn = NULL;
3203 addr->ocsp = OCSP_NOT_REQ;
3204 #endif
3205 #ifdef EXPERIMENTAL_DSN_INFO
3206 addr->smtp_greeting = NULL;
3207 addr->helo_response = NULL;
3208 #endif
3209 }
3210 return first_addr;
3211 }
3212
3213
3214
3215 /*************************************************
3216 * Main entry point *
3217 *************************************************/
3218
3219 /* See local README for interface details. As this is a remote transport, it is
3220 given a chain of addresses to be delivered in one connection, if possible. It
3221 always returns TRUE, indicating that each address has its own independent
3222 status set, except if there is a setting up problem, in which case it returns
3223 FALSE. */
3224
3225 BOOL
3226 smtp_transport_entry(
3227 transport_instance *tblock, /* data for this instantiation */
3228 address_item *addrlist) /* addresses we are working on */
3229 {
3230 int cutoff_retry;
3231 int port;
3232 int hosts_defer = 0;
3233 int hosts_fail = 0;
3234 int hosts_looked_up = 0;
3235 int hosts_retry = 0;
3236 int hosts_serial = 0;
3237 int hosts_total = 0;
3238 int total_hosts_tried = 0;
3239 address_item *addr;
3240 BOOL expired = TRUE;
3241 BOOL continuing = continue_hostname != NULL;
3242 uschar *expanded_hosts = NULL;
3243 uschar *pistring;
3244 uschar *tid = string_sprintf("%s transport", tblock->name);
3245 smtp_transport_options_block *ob =
3246 (smtp_transport_options_block *)(tblock->options_block);
3247 host_item *hostlist = addrlist->host_list;
3248 host_item *host = NULL;
3249
3250 DEBUG(D_transport)
3251 {
3252 debug_printf("%s transport entered\n", tblock->name);
3253 for (addr = addrlist; addr != NULL; addr = addr->next)
3254 debug_printf(" %s\n", addr->address);
3255 if (continuing) debug_printf("already connected to %s [%s]\n",
3256 continue_hostname, continue_host_address);
3257 }
3258
3259 /* Set the flag requesting that these hosts be added to the waiting
3260 database if the delivery fails temporarily or if we are running with
3261 queue_smtp or a 2-stage queue run. This gets unset for certain
3262 kinds of error, typically those that are specific to the message. */
3263
3264 update_waiting = TRUE;
3265
3266 /* If a host list is not defined for the addresses - they must all have the
3267 same one in order to be passed to a single transport - or if the transport has
3268 a host list with hosts_override set, use the host list supplied with the
3269 transport. It is an error for this not to exist. */
3270
3271 if (hostlist == NULL || (ob->hosts_override && ob->hosts != NULL))
3272 {
3273 if (ob->hosts == NULL)
3274 {
3275 addrlist->message = string_sprintf("%s transport called with no hosts set",
3276 tblock->name);
3277 addrlist->transport_return = PANIC;
3278 return FALSE; /* Only top address has status */
3279 }
3280
3281 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
3282 ob->hosts);
3283
3284 /* If the transport's host list contains no '$' characters, and we are not
3285 randomizing, it is fixed and therefore a chain of hosts can be built once
3286 and for all, and remembered for subsequent use by other calls to this
3287 transport. If, on the other hand, the host list does contain '$', or we are
3288 randomizing its order, we have to rebuild it each time. In the fixed case,
3289 as the hosts string will never be used again, it doesn't matter that we
3290 replace all the : characters with zeros. */
3291
3292 if (ob->hostlist == NULL)
3293 {
3294 uschar *s = ob->hosts;
3295
3296 if (Ustrchr(s, '$') != NULL)
3297 {
3298 if (!(expanded_hosts = expand_string(s)))
3299 {
3300 addrlist->message = string_sprintf("failed to expand list of hosts "
3301 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
3302 addrlist->transport_return = search_find_defer? DEFER : PANIC;
3303 return FALSE; /* Only top address has status */
3304 }
3305 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
3306 "\"%s\"\n", s, expanded_hosts);
3307 s = expanded_hosts;
3308 }
3309 else
3310 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
3311
3312 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
3313
3314 /* Check that the expansion yielded something useful. */
3315 if (hostlist == NULL)
3316 {
3317 addrlist->message =
3318 string_sprintf("%s transport has empty hosts setting", tblock->name);
3319 addrlist->transport_return = PANIC;
3320 return FALSE; /* Only top address has status */
3321 }
3322
3323 /* If there was no expansion of hosts, save the host list for
3324 next time. */
3325
3326 if (!expanded_hosts) ob->hostlist = hostlist;
3327 }
3328
3329 /* This is not the first time this transport has been run in this delivery;
3330 the host list was built previously. */
3331
3332 else
3333 hostlist = ob->hostlist;
3334 }
3335
3336 /* The host list was supplied with the address. If hosts_randomize is set, we
3337 must sort it into a random order if it did not come from MX records and has not
3338 already been randomized (but don't bother if continuing down an existing
3339 connection). */
3340
3341 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continuing)
3342 {
3343 host_item *newlist = NULL;
3344 while (hostlist != NULL)
3345 {
3346 host_item *h = hostlist;
3347 hostlist = hostlist->next;
3348
3349 h->sort_key = random_number(100);
3350
3351 if (newlist == NULL)
3352 {
3353 h->next = NULL;
3354 newlist = h;
3355 }
3356 else if (h->sort_key < newlist->sort_key)
3357 {
3358 h->next = newlist;
3359 newlist = h;
3360 }
3361 else
3362 {
3363 host_item *hh = newlist;
3364 while (hh->next != NULL)
3365 {
3366 if (h->sort_key < hh->next->sort_key) break;
3367 hh = hh->next;
3368 }
3369 h->next = hh->next;
3370 hh->next = h;
3371 }
3372 }
3373
3374 hostlist = addrlist->host_list = newlist;
3375 }
3376
3377 /* Sort out the default port. */
3378
3379 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
3380
3381 /* For each host-plus-IP-address on the list:
3382
3383 . If this is a continued delivery and the host isn't the one with the
3384 current connection, skip.
3385
3386 . If the status is unusable (i.e. previously failed or retry checked), skip.
3387
3388 . If no IP address set, get the address, either by turning the name into
3389 an address, calling gethostbyname if gethostbyname is on, or by calling
3390 the DNS. The DNS may yield multiple addresses, in which case insert the
3391 extra ones into the list.
3392
3393 . Get the retry data if not previously obtained for this address and set the
3394 field which remembers the state of this address. Skip if the retry time is
3395 not reached. If not, remember whether retry data was found. The retry string
3396 contains both the name and the IP address.
3397
3398 . Scan the list of addresses and mark those whose status is DEFER as
3399 PENDING_DEFER. These are the only ones that will be processed in this cycle
3400 of the hosts loop.
3401
3402 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
3403 Some addresses may be successfully delivered, others may fail, and yet
3404 others may get temporary errors and so get marked DEFER.
3405
3406 . The return from the delivery attempt is OK if a connection was made and a
3407 valid SMTP dialogue was completed. Otherwise it is DEFER.
3408
3409 . If OK, add a "remove" retry item for this host/IPaddress, if any.
3410
3411 . If fail to connect, or other defer state, add a retry item.
3412
3413 . If there are any addresses whose status is still DEFER, carry on to the
3414 next host/IPaddress, unless we have tried the number of hosts given
3415 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
3416 there is some fancy logic for hosts_max_try that means its limit can be
3417 overstepped in some circumstances.
3418
3419 If we get to the end of the list, all hosts have deferred at least one address,
3420 or not reached their retry times. If delay_after_cutoff is unset, it requests a
3421 delivery attempt to those hosts whose last try was before the arrival time of
3422 the current message. To cope with this, we have to go round the loop a second
3423 time. After that, set the status and error data for any addresses that haven't
3424 had it set already. */
3425
3426 for (cutoff_retry = 0; expired &&
3427 cutoff_retry < ((ob->delay_after_cutoff)? 1 : 2);
3428 cutoff_retry++)
3429 {
3430 host_item *nexthost = NULL;
3431 int unexpired_hosts_tried = 0;
3432
3433 for (host = hostlist;
3434 host != NULL &&
3435 unexpired_hosts_tried < ob->hosts_max_try &&
3436 total_hosts_tried < ob->hosts_max_try_hardlimit;
3437 host = nexthost)
3438 {
3439 int rc;
3440 int host_af;
3441 uschar *rs;
3442 BOOL serialized = FALSE;
3443 BOOL host_is_expired = FALSE;
3444 BOOL message_defer = FALSE;
3445 BOOL some_deferred = FALSE;
3446 address_item *first_addr = NULL;
3447 uschar *interface = NULL;
3448 uschar *retry_host_key = NULL;
3449 uschar *retry_message_key = NULL;
3450 uschar *serialize_key = NULL;
3451
3452 /* Default next host is next host. :-) But this can vary if the
3453 hosts_max_try limit is hit (see below). It may also be reset if a host
3454 address is looked up here (in case the host was multihomed). */
3455
3456 nexthost = host->next;
3457
3458 /* If the address hasn't yet been obtained from the host name, look it up
3459 now, unless the host is already marked as unusable. If it is marked as
3460 unusable, it means that the router was unable to find its IP address (in
3461 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
3462 the lookup failed last time. We don't get this far if *all* MX records
3463 point to non-existent hosts; that is treated as a hard error.
3464
3465 We can just skip this host entirely. When the hosts came from the router,
3466 the address will timeout based on the other host(s); when the address is
3467 looked up below, there is an explicit retry record added.
3468
3469 Note that we mustn't skip unusable hosts if the address is not unset; they
3470 may be needed as expired hosts on the 2nd time round the cutoff loop. */
3471
3472 if (host->address == NULL)
3473 {
3474 int new_port, flags;
3475 host_item *hh;
3476
3477 if (host->status >= hstatus_unusable)
3478 {
3479 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
3480 host->name);
3481 continue;
3482 }
3483
3484 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
3485
3486 /* The host name is permitted to have an attached port. Find it, and
3487 strip it from the name. Just remember it for now. */
3488
3489 new_port = host_item_get_port(host);
3490
3491 /* Count hosts looked up */
3492
3493 hosts_looked_up++;
3494
3495 /* Find by name if so configured, or if it's an IP address. We don't
3496 just copy the IP address, because we need the test-for-local to happen. */
3497
3498 flags = HOST_FIND_BY_A;
3499 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
3500 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
3501
3502 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
3503 rc = host_find_byname(host, NULL, flags, NULL, TRUE);
3504 else
3505 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
3506 &ob->dnssec, /* domains for request/require */
3507 NULL, NULL);
3508
3509 /* Update the host (and any additional blocks, resulting from
3510 multihoming) with a host-specific port, if any. */
3511
3512 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
3513
3514 /* Failure to find the host at this time (usually DNS temporary failure)
3515 is really a kind of routing failure rather than a transport failure.
3516 Therefore we add a retry item of the routing kind, not to stop us trying
3517 to look this name up here again, but to ensure the address gets timed
3518 out if the failures go on long enough. A complete failure at this point
3519 commonly points to a configuration error, but the best action is still
3520 to carry on for the next host. */
3521
3522 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
3523 {
3524 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
3525 expired = FALSE;
3526 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
3527 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
3528 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
3529 host->status = hstatus_unusable;
3530
3531 for (addr = addrlist; addr != NULL; addr = addr->next)
3532 {
3533 if (addr->transport_return != DEFER) continue;
3534 addr->basic_errno = ERRNO_UNKNOWNHOST;
3535 addr->message =
3536 string_sprintf("failed to lookup IP address for %s", host->name);
3537 }
3538 continue;
3539 }
3540
3541 /* If the host is actually the local host, we may have a problem, or
3542 there may be some cunning configuration going on. In the problem case,
3543 log things and give up. The default transport status is already DEFER. */
3544
3545 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
3546 {
3547 for (addr = addrlist; addr != NULL; addr = addr->next)
3548 {
3549 addr->basic_errno = 0;
3550 addr->message = string_sprintf("%s transport found host %s to be "
3551 "local", tblock->name, host->name);
3552 }
3553 goto END_TRANSPORT;
3554 }
3555 } /* End of block for IP address lookup */
3556
3557 /* If this is a continued delivery, we are interested only in the host
3558 which matches the name of the existing open channel. The check is put
3559 here after the local host lookup, in case the name gets expanded as a
3560 result of the lookup. Set expired FALSE, to save the outer loop executing
3561 twice. */
3562
3563 if (continuing && (Ustrcmp(continue_hostname, host->name) != 0 ||
3564 Ustrcmp(continue_host_address, host->address) != 0))
3565 {
3566 expired = FALSE;
3567 continue; /* With next host */
3568 }
3569
3570 /* Reset the default next host in case a multihomed host whose addresses
3571 are not looked up till just above added to the host list. */
3572
3573 nexthost = host->next;
3574
3575 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
3576 domain is in queue_smtp_domains, we don't actually want to attempt any
3577 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
3578 there is a lookup defer in queue_smtp_domains, proceed as if the domain
3579 were not in it. We don't want to hold up all SMTP deliveries! Except when
3580 doing a two-stage queue run, don't do this if forcing. */
3581
3582 if ((!deliver_force || queue_2stage) && (queue_smtp ||
3583 match_isinlist(addrlist->domain,
3584 (const uschar **)&queue_smtp_domains, 0,
3585 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
3586 {
3587 expired = FALSE;
3588 for (addr = addrlist; addr != NULL; addr = addr->next)
3589 {
3590 if (addr->transport_return != DEFER) continue;
3591 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
3592 }
3593 continue; /* With next host */
3594 }
3595
3596 /* Count hosts being considered - purely for an intelligent comment
3597 if none are usable. */
3598
3599 hosts_total++;
3600
3601 /* Set $host and $host address now in case they are needed for the
3602 interface expansion or the serialize_hosts check; they remain set if an
3603 actual delivery happens. */
3604
3605 deliver_host = host->name;
3606 deliver_host_address = host->address;
3607 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
3608 : host->dnssec == DS_NO ? US"no"
3609 : US"";
3610
3611 /* Set up a string for adding to the retry key if the port number is not
3612 the standard SMTP port. A host may have its own port setting that overrides
3613 the default. */
3614
3615 pistring = string_sprintf(":%d", (host->port == PORT_NONE)?
3616 port : host->port);
3617 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
3618
3619 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
3620 string is set, even if constant (as different transports can have different
3621 constant settings), we must add it to the key that is used for retries,
3622 because connections to the same host from a different interface should be
3623 treated separately. */
3624
3625 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET : AF_INET6;
3626 if ((rs = ob->interface) && *rs)
3627 {
3628 if (!smtp_get_interface(rs, host_af, addrlist, &interface, tid))
3629 return FALSE;
3630 pistring = string_sprintf("%s/%s", pistring, interface);
3631 }
3632
3633 /* The first time round the outer loop, check the status of the host by
3634 inspecting the retry data. The second time round, we are interested only
3635 in expired hosts that haven't been tried since this message arrived. */
3636
3637 if (cutoff_retry == 0)
3638 {
3639 BOOL incl_ip;
3640 /* Ensure the status of the address is set by checking retry data if
3641 necessary. There may be host-specific retry data (applicable to all
3642 messages) and also data for retries of a specific message at this host.
3643 If either of these retry records are actually read, the keys used are
3644 returned to save recomputing them later. */
3645
3646 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3647 US"retry_include_ip_address", ob->retry_include_ip_address,
3648 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3649 continue; /* with next host */
3650
3651 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
3652 incl_ip, &retry_host_key, &retry_message_key);
3653
3654 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
3655 (host->address == NULL)? US"" : host->address, pistring,
3656 (host->status == hstatus_usable)? "usable" :
3657 (host->status == hstatus_unusable)? "unusable" :
3658 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
3659
3660 /* Skip this address if not usable at this time, noting if it wasn't
3661 actually expired, both locally and in the address. */
3662
3663 switch (host->status)
3664 {
3665 case hstatus_unusable:
3666 expired = FALSE;
3667 setflag(addrlist, af_retry_skipped);
3668 /* Fall through */
3669
3670 case hstatus_unusable_expired:
3671 switch (host->why)
3672 {
3673 case hwhy_retry: hosts_retry++; break;
3674 case hwhy_failed: hosts_fail++; break;
3675 case hwhy_deferred: hosts_defer++; break;
3676 }
3677
3678 /* If there was a retry message key, implying that previously there
3679 was a message-specific defer, we don't want to update the list of
3680 messages waiting for these hosts. */
3681
3682 if (retry_message_key != NULL) update_waiting = FALSE;
3683 continue; /* With the next host or IP address */
3684 }
3685 }
3686
3687 /* Second time round the loop: if the address is set but expired, and
3688 the message is newer than the last try, let it through. */
3689
3690 else
3691 {
3692 if (host->address == NULL ||
3693 host->status != hstatus_unusable_expired ||
3694 host->last_try > received_time)
3695 continue;
3696 DEBUG(D_transport)
3697 debug_printf("trying expired host %s [%s]%s\n",
3698 host->name, host->address, pistring);
3699 host_is_expired = TRUE;
3700 }
3701
3702 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
3703 it remains TRUE only if all hosts are expired and none are actually tried.
3704 */
3705
3706 expired = FALSE;
3707
3708 /* If this host is listed as one to which access must be serialized,
3709 see if another Exim process has a connection to it, and if so, skip
3710 this host. If not, update the database to record our connection to it
3711 and remember this for later deletion. Do not do any of this if we are
3712 sending the message down a pre-existing connection. */
3713
3714 if (!continuing &&
3715 verify_check_given_host(&ob->serialize_hosts, host) == OK)
3716 {
3717 serialize_key = string_sprintf("host-serialize-%s", host->name);
3718 if (!enq_start(serialize_key, 1))
3719 {
3720 DEBUG(D_transport)
3721 debug_printf("skipping host %s because another Exim process "
3722 "is connected to it\n", host->name);
3723 hosts_serial++;
3724 continue;
3725 }
3726 serialized = TRUE;
3727 }
3728
3729 /* OK, we have an IP address that is not waiting for its retry time to
3730 arrive (it might be expired) OR (second time round the loop) we have an
3731 expired host that hasn't been tried since the message arrived. Have a go
3732 at delivering the message to it. First prepare the addresses by flushing
3733 out the result of previous attempts, and finding the first address that
3734 is still to be delivered. */
3735
3736 first_addr = prepare_addresses(addrlist, host);
3737
3738 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
3739 message_id, host->name, host->address, addrlist->address,
3740 (addrlist->next == NULL)? "" : ", ...");
3741
3742 set_process_info("delivering %s to %s [%s] (%s%s)",
3743 message_id, host->name, host->address, addrlist->address,
3744 (addrlist->next == NULL)? "" : ", ...");
3745
3746 /* This is not for real; don't do the delivery. If there are
3747 any remaining hosts, list them. */
3748
3749 if (dont_deliver)
3750 {
3751 host_item *host2;
3752 set_errno_nohost(addrlist, 0, NULL, OK, FALSE);
3753 for (addr = addrlist; addr != NULL; addr = addr->next)
3754 {
3755 addr->host_used = host;
3756 addr->special_action = '*';
3757 addr->message = US"delivery bypassed by -N option";
3758 }
3759 DEBUG(D_transport)
3760 {
3761 debug_printf("*** delivery by %s transport bypassed by -N option\n"
3762 "*** host and remaining hosts:\n", tblock->name);
3763 for (host2 = host; host2 != NULL; host2 = host2->next)
3764 debug_printf(" %s [%s]\n", host2->name,
3765 (host2->address == NULL)? US"unset" : host2->address);
3766 }
3767 rc = OK;
3768 }
3769
3770 /* This is for real. If the host is expired, we don't count it for
3771 hosts_max_retry. This ensures that all hosts must expire before an address
3772 is timed out, unless hosts_max_try_hardlimit (which protects against
3773 lunatic DNS configurations) is reached.
3774
3775 If the host is not expired and we are about to hit the hosts_max_retry
3776 limit, check to see if there is a subsequent hosts with a different MX
3777 value. If so, make that the next host, and don't count this one. This is a
3778 heuristic to make sure that different MXs do get tried. With a normal kind
3779 of retry rule, they would get tried anyway when the earlier hosts were
3780 delayed, but if the domain has a "retry every time" type of rule - as is
3781 often used for the the very large ISPs, that won't happen. */
3782
3783 else
3784 {
3785 host_item * thost;
3786 /* Make a copy of the host if it is local to this invocation
3787 of the transport. */
3788
3789 if (expanded_hosts)
3790 {
3791 thost = store_get(sizeof(host_item));
3792 *thost = *host;
3793 thost->name = string_copy(host->name);
3794 thost->address = string_copy(host->address);
3795 }
3796 else
3797 thost = host;
3798
3799 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
3800 {
3801 host_item *h;
3802 DEBUG(D_transport)
3803 debug_printf("hosts_max_try limit reached with this host\n");
3804 for (h = host; h; h = h->next) if (h->mx != host->mx)
3805 {
3806 nexthost = h;
3807 unexpired_hosts_tried--;
3808 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
3809 "and will be tried\n");
3810 break;
3811 }
3812 }
3813
3814 /* Attempt the delivery. */
3815
3816 total_hosts_tried++;
3817 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
3818 &message_defer, FALSE);
3819
3820 /* Yield is one of:
3821 OK => connection made, each address contains its result;
3822 message_defer is set for message-specific defers (when all
3823 recipients are marked defer)
3824 DEFER => there was a non-message-specific delivery problem;
3825 ERROR => there was a problem setting up the arguments for a filter,
3826 or there was a problem with expanding added headers
3827 */
3828
3829 /* If the result is not OK, there was a non-message-specific problem.
3830 If the result is DEFER, we need to write to the logs saying what happened
3831 for this particular host, except in the case of authentication and TLS
3832 failures, where the log has already been written. If all hosts defer a
3833 general message is written at the end. */
3834
3835 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL &&
3836 first_addr->basic_errno != ERRNO_TLSFAILURE)
3837 write_logs(first_addr, host);
3838
3839 #ifndef DISABLE_EVENT
3840 if (rc == DEFER)
3841 deferred_event_raise(first_addr, host);
3842 #endif
3843
3844 /* If STARTTLS was accepted, but there was a failure in setting up the
3845 TLS session (usually a certificate screwup), and the host is not in
3846 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
3847 TLS forcibly turned off. We have to start from scratch with a new SMTP
3848 connection. That's why the retry is done from here, not from within
3849 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
3850 session, so the in-clear transmission after those errors, if permitted,
3851 happens inside smtp_deliver().] */
3852
3853 #ifdef SUPPORT_TLS
3854 if ( rc == DEFER
3855 && first_addr->basic_errno == ERRNO_TLSFAILURE
3856 && ob->tls_tempfail_tryclear
3857 && verify_check_given_host(&ob->hosts_require_tls, host) != OK
3858 )
3859 {
3860 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
3861 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
3862 first_addr = prepare_addresses(addrlist, host);
3863 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
3864 &message_defer, TRUE);
3865 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
3866 write_logs(first_addr, host);
3867 # ifndef DISABLE_EVENT
3868 if (rc == DEFER)
3869 deferred_event_raise(first_addr, host);
3870 # endif
3871 }
3872 #endif /*SUPPORT_TLS*/
3873 }
3874
3875 /* Delivery attempt finished */
3876
3877 rs = (rc == OK)? US"OK" : (rc == DEFER)? US"DEFER" : (rc == ERROR)?
3878 US"ERROR" : US"?";
3879
3880 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
3881 message_id, host->name, host->address, addrlist->address,
3882 (addrlist->next == NULL)? "" : " (& others)", rs);
3883
3884 /* Release serialization if set up */
3885
3886 if (serialized) enq_end(serialize_key);
3887
3888 /* If the result is DEFER, or if a host retry record is known to exist, we
3889 need to add an item to the retry chain for updating the retry database
3890 at the end of delivery. We only need to add the item to the top address,
3891 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
3892 for any other delivery attempts using the same address. (It is copied into
3893 the unusable tree at the outer level, so even if different address blocks
3894 contain the same address, it still won't get tried again.) */
3895
3896 if (rc == DEFER || retry_host_key != NULL)
3897 {
3898 int delete_flag = (rc != DEFER)? rf_delete : 0;
3899 if (retry_host_key == NULL)
3900 {
3901 BOOL incl_ip;
3902 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3903 US"retry_include_ip_address", ob->retry_include_ip_address,
3904 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3905 incl_ip = TRUE; /* error; use most-specific retry record */
3906
3907 retry_host_key = incl_ip ?
3908 string_sprintf("T:%S:%s%s", host->name, host->address, pistring) :
3909 string_sprintf("T:%S%s", host->name, pistring);
3910 }
3911
3912 /* If a delivery of another message over an existing SMTP connection
3913 yields DEFER, we do NOT set up retry data for the host. This covers the
3914 case when there are delays in routing the addresses in the second message
3915 that are so long that the server times out. This is alleviated by not
3916 routing addresses that previously had routing defers when handling an
3917 existing connection, but even so, this case may occur (e.g. if a
3918 previously happily routed address starts giving routing defers). If the
3919 host is genuinely down, another non-continued message delivery will
3920 notice it soon enough. */
3921
3922 if (delete_flag != 0 || !continuing)
3923 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
3924
3925 /* We may have tried an expired host, if its retry time has come; ensure
3926 the status reflects the expiry for the benefit of any other addresses. */
3927
3928 if (rc == DEFER)
3929 {
3930 host->status = (host_is_expired)?
3931 hstatus_unusable_expired : hstatus_unusable;
3932 host->why = hwhy_deferred;
3933 }
3934 }
3935
3936 /* If message_defer is set (host was OK, but every recipient got deferred
3937 because of some message-specific problem), or if that had happened
3938 previously so that a message retry key exists, add an appropriate item
3939 to the retry chain. Note that if there was a message defer but now there is
3940 a host defer, the message defer record gets deleted. That seems perfectly
3941 reasonable. Also, stop the message from being remembered as waiting
3942 for specific hosts. */
3943
3944 if (message_defer || retry_message_key != NULL)
3945 {
3946 int delete_flag = message_defer? 0 : rf_delete;
3947 if (retry_message_key == NULL)
3948 {
3949 BOOL incl_ip;
3950 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3951 US"retry_include_ip_address", ob->retry_include_ip_address,
3952 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3953 incl_ip = TRUE; /* error; use most-specific retry record */
3954
3955 retry_message_key = incl_ip ?
3956 string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
3957 message_id) :
3958 string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
3959 }
3960 retry_add_item(addrlist, retry_message_key,
3961 rf_message | rf_host | delete_flag);
3962 update_waiting = FALSE;
3963 }
3964
3965 /* Any return other than DEFER (that is, OK or ERROR) means that the
3966 addresses have got their final statuses filled in for this host. In the OK
3967 case, see if any of them are deferred. */
3968
3969 if (rc == OK)
3970 for (addr = addrlist; addr; addr = addr->next)
3971 if (addr->transport_return == DEFER)
3972 {
3973 some_deferred = TRUE;
3974 break;
3975 }
3976
3977 /* If no addresses deferred or the result was ERROR, return. We do this for
3978 ERROR because a failing filter set-up or add_headers expansion is likely to
3979 fail for any host we try. */
3980
3981 if (rc == ERROR || (rc == OK && !some_deferred))
3982 {
3983 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3984 return TRUE; /* Each address has its status */
3985 }
3986
3987 /* If the result was DEFER or some individual addresses deferred, let
3988 the loop run to try other hosts with the deferred addresses, except for the
3989 case when we were trying to deliver down an existing channel and failed.
3990 Don't try any other hosts in this case. */
3991
3992 if (continuing) break;
3993
3994 /* If the whole delivery, or some individual addresses, were deferred and
3995 there are more hosts that could be tried, do not count this host towards
3996 the hosts_max_try limit if the age of the message is greater than the
3997 maximum retry time for this host. This means we may try try all hosts,
3998 ignoring the limit, when messages have been around for some time. This is
3999 important because if we don't try all hosts, the address will never time
4000 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
4001
4002 if ((rc == DEFER || some_deferred) && nexthost != NULL)
4003 {
4004 BOOL timedout;
4005 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
4006
4007 if (retry != NULL && retry->rules != NULL)
4008 {
4009 retry_rule *last_rule;
4010 for (last_rule = retry->rules;
4011 last_rule->next != NULL;
4012 last_rule = last_rule->next);
4013 timedout = time(NULL) - received_time > last_rule->timeout;
4014 }
4015 else timedout = TRUE; /* No rule => timed out */
4016
4017 if (timedout)
4018 {
4019 unexpired_hosts_tried--;
4020 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
4021 "hosts_max_try (message older than host's retry time)\n");
4022 }
4023 }
4024 } /* End of loop for trying multiple hosts. */
4025
4026 /* This is the end of the loop that repeats iff expired is TRUE and
4027 ob->delay_after_cutoff is FALSE. The second time round we will
4028 try those hosts that haven't been tried since the message arrived. */
4029
4030 DEBUG(D_transport)
4031 {
4032 debug_printf("all IP addresses skipped or deferred at least one address\n");
4033 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
4034 debug_printf("retrying IP addresses not tried since message arrived\n");
4035 }
4036 }
4037
4038
4039 /* Get here if all IP addresses are skipped or defer at least one address. In
4040 MUA wrapper mode, this will happen only for connection or other non-message-
4041 specific failures. Force the delivery status for all addresses to FAIL. */
4042
4043 if (mua_wrapper)
4044 {
4045 for (addr = addrlist; addr != NULL; addr = addr->next)
4046 addr->transport_return = FAIL;
4047 goto END_TRANSPORT;
4048 }
4049
4050 /* In the normal, non-wrapper case, add a standard message to each deferred
4051 address if there hasn't been an error, that is, if it hasn't actually been
4052 tried this time. The variable "expired" will be FALSE if any deliveries were
4053 actually tried, or if there was at least one host that was not expired. That
4054 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
4055 a delivery has been tried, an error code will be set, and the failing of the
4056 message is handled by the retry code later.
4057
4058 If queue_smtp is set, or this transport was called to send a subsequent message
4059 down an existing TCP/IP connection, and something caused the host not to be
4060 found, we end up here, but can detect these cases and handle them specially. */
4061
4062 for (addr = addrlist; addr; addr = addr->next)
4063 {
4064 /* If host is not NULL, it means that we stopped processing the host list
4065 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
4066 means we need to behave as if some hosts were skipped because their retry
4067 time had not come. Specifically, this prevents the address from timing out.
4068 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
4069 hosts were tried. */
4070
4071 if (host)
4072 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
4073 {
4074 DEBUG(D_transport)
4075 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
4076 "hosts were tried\n");
4077 }
4078 else
4079 {
4080 DEBUG(D_transport)
4081 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
4082 setflag(addr, af_retry_skipped);
4083 }
4084
4085 if (queue_smtp) /* no deliveries attempted */
4086 {
4087 addr->transport_return = DEFER;
4088 addr->basic_errno = 0;
4089 addr->message = US"SMTP delivery explicitly queued";
4090 }
4091
4092 else if ( addr->transport_return == DEFER
4093 && (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0)
4094 && !addr->message
4095 )
4096 {
4097 addr->basic_errno = ERRNO_HRETRY;
4098 if (continue_hostname)
4099 addr->message = US"no host found for existing SMTP connection";
4100 else if (expired)
4101 {
4102 setflag(addr, af_pass_message); /* This is not a security risk */
4103 addr->message = string_sprintf(
4104 "all hosts%s have been failing for a long time %s",
4105 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"",
4106 ob->delay_after_cutoff
4107 ? US"(and retry time not reached)"
4108 : US"and were last tried after this message arrived");
4109
4110 /* If we are already using fallback hosts, or there are no fallback hosts
4111 defined, convert the result to FAIL to cause a bounce. */
4112
4113 if (addr->host_list == addr->fallback_hosts || !addr->fallback_hosts)
4114 addr->transport_return = FAIL;
4115 }
4116 else
4117 {
4118 const char * s;
4119 if (hosts_retry == hosts_total)
4120 s = "retry time not reached for any host%s";
4121 else if (hosts_fail == hosts_total)
4122 s = "all host address lookups%s failed permanently";
4123 else if (hosts_defer == hosts_total)
4124 s = "all host address lookups%s failed temporarily";
4125 else if (hosts_serial == hosts_total)
4126 s = "connection limit reached for all hosts%s";
4127 else if (hosts_fail+hosts_defer == hosts_total)
4128 s = "all host address lookups%s failed";
4129 else
4130 s = "some host address lookups failed and retry time "
4131 "not reached for other hosts or connection limit reached%s";
4132
4133 addr->message = string_sprintf(s,
4134 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"");
4135 }
4136 }
4137 }
4138
4139 /* Update the database which keeps information about which messages are waiting
4140 for which hosts to become available. For some message-specific errors, the
4141 update_waiting flag is turned off because we don't want follow-on deliveries in
4142 those cases. If this transport instance is explicitly limited to one message
4143 per connection then follow-on deliveries are not possible and there's no need
4144 to create/update the per-transport wait-<transport_name> database. */
4145
4146 if (update_waiting && tblock->connection_max_messages != 1)
4147 transport_update_waiting(hostlist, tblock->name);
4148
4149 END_TRANSPORT:
4150
4151 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
4152
4153 return TRUE; /* Each address has its status */
4154 }
4155
4156 /* vi: aw ai sw=2
4157 */
4158 /* End of transport/smtp.c */
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