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Move DSN support to mainline
[exim.git] / src / src / transports / smtp.c
1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
4
5 /* Copyright (c) University of Cambridge 1995 - 2014 */
6 /* See the file NOTICE for conditions of use and distribution. */
7
8 #include "../exim.h"
9 #include "smtp.h"
10
11 #define PENDING 256
12 #define PENDING_DEFER (PENDING + DEFER)
13 #define PENDING_OK (PENDING + OK)
14
15
16 /* Options specific to the smtp transport. This transport also supports LMTP
17 over TCP/IP. The options must be in alphabetic order (note that "_" comes
18 before the lower case letters). Some live in the transport_instance block so as
19 to be publicly visible; these are flagged with opt_public. */
20
21 optionlist smtp_transport_options[] = {
22 { "*expand_multi_domain", opt_stringptr | opt_hidden | opt_public,
23 (void *)offsetof(transport_instance, expand_multi_domain) },
24 { "*expand_retry_include_ip_address", opt_stringptr | opt_hidden,
25 (void *)(offsetof(smtp_transport_options_block, expand_retry_include_ip_address)) },
26
27 { "address_retry_include_sender", opt_bool,
28 (void *)offsetof(smtp_transport_options_block, address_retry_include_sender) },
29 { "allow_localhost", opt_bool,
30 (void *)offsetof(smtp_transport_options_block, allow_localhost) },
31 { "authenticated_sender", opt_stringptr,
32 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
33 { "authenticated_sender_force", opt_bool,
34 (void *)offsetof(smtp_transport_options_block, authenticated_sender_force) },
35 { "command_timeout", opt_time,
36 (void *)offsetof(smtp_transport_options_block, command_timeout) },
37 { "connect_timeout", opt_time,
38 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
39 { "connection_max_messages", opt_int | opt_public,
40 (void *)offsetof(transport_instance, connection_max_messages) },
41 { "data_timeout", opt_time,
42 (void *)offsetof(smtp_transport_options_block, data_timeout) },
43 { "delay_after_cutoff", opt_bool,
44 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
45 #ifndef DISABLE_DKIM
46 { "dkim_canon", opt_stringptr,
47 (void *)offsetof(smtp_transport_options_block, dkim_canon) },
48 { "dkim_domain", opt_stringptr,
49 (void *)offsetof(smtp_transport_options_block, dkim_domain) },
50 { "dkim_private_key", opt_stringptr,
51 (void *)offsetof(smtp_transport_options_block, dkim_private_key) },
52 { "dkim_selector", opt_stringptr,
53 (void *)offsetof(smtp_transport_options_block, dkim_selector) },
54 { "dkim_sign_headers", opt_stringptr,
55 (void *)offsetof(smtp_transport_options_block, dkim_sign_headers) },
56 { "dkim_strict", opt_stringptr,
57 (void *)offsetof(smtp_transport_options_block, dkim_strict) },
58 #endif
59 { "dns_qualify_single", opt_bool,
60 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
61 { "dns_search_parents", opt_bool,
62 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
63 { "dnssec_request_domains", opt_stringptr,
64 (void *)offsetof(smtp_transport_options_block, dnssec_request_domains) },
65 { "dnssec_require_domains", opt_stringptr,
66 (void *)offsetof(smtp_transport_options_block, dnssec_require_domains) },
67 { "dscp", opt_stringptr,
68 (void *)offsetof(smtp_transport_options_block, dscp) },
69 { "fallback_hosts", opt_stringptr,
70 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
71 { "final_timeout", opt_time,
72 (void *)offsetof(smtp_transport_options_block, final_timeout) },
73 { "gethostbyname", opt_bool,
74 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
75 #ifdef SUPPORT_TLS
76 /* These are no longer honoured, as of Exim 4.80; for now, we silently
77 ignore; 4.83 will warn, and a later-still release will remove
78 these options, so that using them becomes an error. */
79 { "gnutls_require_kx", opt_stringptr,
80 (void *)offsetof(smtp_transport_options_block, gnutls_require_kx) },
81 { "gnutls_require_mac", opt_stringptr,
82 (void *)offsetof(smtp_transport_options_block, gnutls_require_mac) },
83 { "gnutls_require_protocols", opt_stringptr,
84 (void *)offsetof(smtp_transport_options_block, gnutls_require_proto) },
85 #endif
86 { "helo_data", opt_stringptr,
87 (void *)offsetof(smtp_transport_options_block, helo_data) },
88 { "hosts", opt_stringptr,
89 (void *)offsetof(smtp_transport_options_block, hosts) },
90 { "hosts_avoid_esmtp", opt_stringptr,
91 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
92 { "hosts_avoid_pipelining", opt_stringptr,
93 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
94 #ifdef SUPPORT_TLS
95 { "hosts_avoid_tls", opt_stringptr,
96 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
97 #endif
98 { "hosts_max_try", opt_int,
99 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
100 { "hosts_max_try_hardlimit", opt_int,
101 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
102 #ifdef SUPPORT_TLS
103 { "hosts_nopass_tls", opt_stringptr,
104 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
105 #endif
106 { "hosts_override", opt_bool,
107 (void *)offsetof(smtp_transport_options_block, hosts_override) },
108 { "hosts_randomize", opt_bool,
109 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
110 #if defined(SUPPORT_TLS) && !defined(DISABLE_OCSP)
111 { "hosts_request_ocsp", opt_stringptr,
112 (void *)offsetof(smtp_transport_options_block, hosts_request_ocsp) },
113 #endif
114 { "hosts_require_auth", opt_stringptr,
115 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
116 #ifdef SUPPORT_TLS
117 # ifdef EXPERIMENTAL_DANE
118 { "hosts_require_dane", opt_stringptr,
119 (void *)offsetof(smtp_transport_options_block, hosts_require_dane) },
120 # endif
121 # ifndef DISABLE_OCSP
122 { "hosts_require_ocsp", opt_stringptr,
123 (void *)offsetof(smtp_transport_options_block, hosts_require_ocsp) },
124 # endif
125 { "hosts_require_tls", opt_stringptr,
126 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
127 #endif
128 { "hosts_try_auth", opt_stringptr,
129 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
130 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
131 { "hosts_try_dane", opt_stringptr,
132 (void *)offsetof(smtp_transport_options_block, hosts_try_dane) },
133 #endif
134 #ifndef DISABLE_PRDR
135 { "hosts_try_prdr", opt_stringptr,
136 (void *)offsetof(smtp_transport_options_block, hosts_try_prdr) },
137 #endif
138 #ifdef SUPPORT_TLS
139 { "hosts_verify_avoid_tls", opt_stringptr,
140 (void *)offsetof(smtp_transport_options_block, hosts_verify_avoid_tls) },
141 #endif
142 { "interface", opt_stringptr,
143 (void *)offsetof(smtp_transport_options_block, interface) },
144 { "keepalive", opt_bool,
145 (void *)offsetof(smtp_transport_options_block, keepalive) },
146 { "lmtp_ignore_quota", opt_bool,
147 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
148 { "max_rcpt", opt_int | opt_public,
149 (void *)offsetof(transport_instance, max_addresses) },
150 { "multi_domain", opt_expand_bool | opt_public,
151 (void *)offsetof(transport_instance, multi_domain) },
152 { "port", opt_stringptr,
153 (void *)offsetof(smtp_transport_options_block, port) },
154 { "protocol", opt_stringptr,
155 (void *)offsetof(smtp_transport_options_block, protocol) },
156 { "retry_include_ip_address", opt_expand_bool,
157 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
158 { "serialize_hosts", opt_stringptr,
159 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
160 { "size_addition", opt_int,
161 (void *)offsetof(smtp_transport_options_block, size_addition) }
162 #ifdef SUPPORT_TLS
163 ,{ "tls_certificate", opt_stringptr,
164 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
165 { "tls_crl", opt_stringptr,
166 (void *)offsetof(smtp_transport_options_block, tls_crl) },
167 { "tls_dh_min_bits", opt_int,
168 (void *)offsetof(smtp_transport_options_block, tls_dh_min_bits) },
169 { "tls_privatekey", opt_stringptr,
170 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
171 { "tls_require_ciphers", opt_stringptr,
172 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
173 { "tls_sni", opt_stringptr,
174 (void *)offsetof(smtp_transport_options_block, tls_sni) },
175 { "tls_tempfail_tryclear", opt_bool,
176 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
177 { "tls_try_verify_hosts", opt_stringptr,
178 (void *)offsetof(smtp_transport_options_block, tls_try_verify_hosts) },
179 { "tls_verify_cert_hostnames", opt_stringptr,
180 (void *)offsetof(smtp_transport_options_block,tls_verify_cert_hostnames)},
181 { "tls_verify_certificates", opt_stringptr,
182 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) },
183 { "tls_verify_hosts", opt_stringptr,
184 (void *)offsetof(smtp_transport_options_block, tls_verify_hosts) }
185 #endif
186 };
187
188 /* Size of the options list. An extern variable has to be used so that its
189 address can appear in the tables drtables.c. */
190
191 int smtp_transport_options_count =
192 sizeof(smtp_transport_options)/sizeof(optionlist);
193
194 /* Default private options block for the smtp transport. */
195
196 smtp_transport_options_block smtp_transport_option_defaults = {
197 NULL, /* hosts */
198 NULL, /* fallback_hosts */
199 NULL, /* hostlist */
200 NULL, /* fallback_hostlist */
201 NULL, /* authenticated_sender */
202 US"$primary_hostname", /* helo_data */
203 NULL, /* interface */
204 NULL, /* port */
205 US"smtp", /* protocol */
206 NULL, /* DSCP */
207 NULL, /* serialize_hosts */
208 NULL, /* hosts_try_auth */
209 NULL, /* hosts_require_auth */
210 #ifdef EXPERIMENTAL_DANE
211 NULL, /* hosts_try_dane */
212 NULL, /* hosts_require_dane */
213 #endif
214 #ifndef DISABLE_PRDR
215 US"*", /* hosts_try_prdr */
216 #endif
217 #ifndef DISABLE_OCSP
218 US"*", /* hosts_request_ocsp (except under DANE; tls_client_start()) */
219 NULL, /* hosts_require_ocsp */
220 #endif
221 NULL, /* hosts_require_tls */
222 NULL, /* hosts_avoid_tls */
223 US"*", /* hosts_verify_avoid_tls */
224 NULL, /* hosts_avoid_pipelining */
225 NULL, /* hosts_avoid_esmtp */
226 NULL, /* hosts_nopass_tls */
227 5*60, /* command_timeout */
228 5*60, /* connect_timeout; shorter system default overrides */
229 5*60, /* data timeout */
230 10*60, /* final timeout */
231 1024, /* size_addition */
232 5, /* hosts_max_try */
233 50, /* hosts_max_try_hardlimit */
234 TRUE, /* address_retry_include_sender */
235 FALSE, /* allow_localhost */
236 FALSE, /* authenticated_sender_force */
237 FALSE, /* gethostbyname */
238 TRUE, /* dns_qualify_single */
239 FALSE, /* dns_search_parents */
240 NULL, /* dnssec_request_domains */
241 NULL, /* dnssec_require_domains */
242 TRUE, /* delay_after_cutoff */
243 FALSE, /* hosts_override */
244 FALSE, /* hosts_randomize */
245 TRUE, /* keepalive */
246 FALSE, /* lmtp_ignore_quota */
247 NULL, /* expand_retry_include_ip_address */
248 TRUE /* retry_include_ip_address */
249 #ifdef SUPPORT_TLS
250 ,NULL, /* tls_certificate */
251 NULL, /* tls_crl */
252 NULL, /* tls_privatekey */
253 NULL, /* tls_require_ciphers */
254 NULL, /* gnutls_require_kx */
255 NULL, /* gnutls_require_mac */
256 NULL, /* gnutls_require_proto */
257 NULL, /* tls_sni */
258 US"system", /* tls_verify_certificates */
259 EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
260 /* tls_dh_min_bits */
261 TRUE, /* tls_tempfail_tryclear */
262 NULL, /* tls_verify_hosts */
263 US"*", /* tls_try_verify_hosts */
264 US"*" /* tls_verify_cert_hostnames */
265 #endif
266 #ifndef DISABLE_DKIM
267 ,NULL, /* dkim_canon */
268 NULL, /* dkim_domain */
269 NULL, /* dkim_private_key */
270 NULL, /* dkim_selector */
271 NULL, /* dkim_sign_headers */
272 NULL /* dkim_strict */
273 #endif
274 };
275
276 /* some DSN flags for use later */
277
278 static int rf_list[] = {rf_notify_never, rf_notify_success,
279 rf_notify_failure, rf_notify_delay };
280
281 static uschar *rf_names[] = { US"NEVER", US"SUCCESS", US"FAILURE", US"DELAY" };
282
283
284
285 /* Local statics */
286
287 static uschar *smtp_command; /* Points to last cmd for error messages */
288 static uschar *mail_command; /* Points to MAIL cmd for error messages */
289 static BOOL update_waiting; /* TRUE to update the "wait" database */
290
291
292 /*************************************************
293 * Setup entry point *
294 *************************************************/
295
296 /* This function is called when the transport is about to be used,
297 but before running it in a sub-process. It is used for two things:
298
299 (1) To set the fallback host list in addresses, when delivering.
300 (2) To pass back the interface, port, protocol, and other options, for use
301 during callout verification.
302
303 Arguments:
304 tblock pointer to the transport instance block
305 addrlist list of addresses about to be transported
306 tf if not NULL, pointer to block in which to return options
307 uid the uid that will be set (not used)
308 gid the gid that will be set (not used)
309 errmsg place for error message (not used)
310
311 Returns: OK always (FAIL, DEFER not used)
312 */
313
314 static int
315 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
316 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
317 {
318 smtp_transport_options_block *ob =
319 (smtp_transport_options_block *)(tblock->options_block);
320
321 errmsg = errmsg; /* Keep picky compilers happy */
322 uid = uid;
323 gid = gid;
324
325 /* Pass back options if required. This interface is getting very messy. */
326
327 if (tf != NULL)
328 {
329 tf->interface = ob->interface;
330 tf->port = ob->port;
331 tf->protocol = ob->protocol;
332 tf->hosts = ob->hosts;
333 tf->hosts_override = ob->hosts_override;
334 tf->hosts_randomize = ob->hosts_randomize;
335 tf->gethostbyname = ob->gethostbyname;
336 tf->qualify_single = ob->dns_qualify_single;
337 tf->search_parents = ob->dns_search_parents;
338 tf->helo_data = ob->helo_data;
339 }
340
341 /* Set the fallback host list for all the addresses that don't have fallback
342 host lists, provided that the local host wasn't present in the original host
343 list. */
344
345 if (!testflag(addrlist, af_local_host_removed))
346 {
347 for (; addrlist != NULL; addrlist = addrlist->next)
348 if (addrlist->fallback_hosts == NULL)
349 addrlist->fallback_hosts = ob->fallback_hostlist;
350 }
351
352 return OK;
353 }
354
355
356
357 /*************************************************
358 * Initialization entry point *
359 *************************************************/
360
361 /* Called for each instance, after its options have been read, to
362 enable consistency checks to be done, or anything else that needs
363 to be set up.
364
365 Argument: pointer to the transport instance block
366 Returns: nothing
367 */
368
369 void
370 smtp_transport_init(transport_instance *tblock)
371 {
372 smtp_transport_options_block *ob =
373 (smtp_transport_options_block *)(tblock->options_block);
374
375 /* Retry_use_local_part defaults FALSE if unset */
376
377 if (tblock->retry_use_local_part == TRUE_UNSET)
378 tblock->retry_use_local_part = FALSE;
379
380 /* Set the default port according to the protocol */
381
382 if (ob->port == NULL)
383 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
384 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
385
386 /* Set up the setup entry point, to be called before subprocesses for this
387 transport. */
388
389 tblock->setup = smtp_transport_setup;
390
391 /* Complain if any of the timeouts are zero. */
392
393 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
394 ob->final_timeout <= 0)
395 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
396 "command, data, or final timeout value is zero for %s transport",
397 tblock->name);
398
399 /* If hosts_override is set and there are local hosts, set the global
400 flag that stops verify from showing router hosts. */
401
402 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
403
404 /* If there are any fallback hosts listed, build a chain of host items
405 for them, but do not do any lookups at this time. */
406
407 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
408
409 #ifdef SUPPORT_TLS
410 if ( ob->gnutls_require_kx
411 || ob->gnutls_require_mac
412 || ob->gnutls_require_proto)
413 log_write(0, LOG_MAIN, "WARNING: smtp transport options"
414 " gnutls_require_kx, gnutls_require_mac and gnutls_require_protocols"
415 " are obsolete\n");
416 #endif
417 }
418
419
420
421
422
423 /*************************************************
424 * Set delivery info into all active addresses *
425 *************************************************/
426
427 /* Only addresses whose status is >= PENDING are relevant. A lesser
428 status means that an address is not currently being processed.
429
430 Arguments:
431 addrlist points to a chain of addresses
432 errno_value to put in each address's errno field
433 msg to put in each address's message field
434 rc to put in each address's transport_return field
435 pass_message if TRUE, set the "pass message" flag in the address
436 host if set, mark addrs as having used this host
437
438 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
439 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
440 this particular type of timeout.
441
442 Returns: nothing
443 */
444
445 static void
446 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
447 BOOL pass_message, host_item * host)
448 {
449 address_item *addr;
450 int orvalue = 0;
451 if (errno_value == ERRNO_CONNECTTIMEOUT)
452 {
453 errno_value = ETIMEDOUT;
454 orvalue = RTEF_CTOUT;
455 }
456 for (addr = addrlist; addr != NULL; addr = addr->next)
457 {
458 if (addr->transport_return < PENDING) continue;
459 addr->basic_errno = errno_value;
460 addr->more_errno |= orvalue;
461 if (msg != NULL)
462 {
463 addr->message = msg;
464 if (pass_message) setflag(addr, af_pass_message);
465 }
466 addr->transport_return = rc;
467 if (host)
468 addr->host_used = host;
469 }
470 }
471
472
473
474 /*************************************************
475 * Check an SMTP response *
476 *************************************************/
477
478 /* This function is given an errno code and the SMTP response buffer
479 to analyse, together with the host identification for generating messages. It
480 sets an appropriate message and puts the first digit of the response code into
481 the yield variable. If no response was actually read, a suitable digit is
482 chosen.
483
484 Arguments:
485 host the current host, to get its name for messages
486 errno_value pointer to the errno value
487 more_errno from the top address for use with ERRNO_FILTER_FAIL
488 buffer the SMTP response buffer
489 yield where to put a one-digit SMTP response code
490 message where to put an errror message
491 pass_message set TRUE if message is an SMTP response
492
493 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
494 */
495
496 static BOOL
497 check_response(host_item *host, int *errno_value, int more_errno,
498 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
499 {
500 uschar *pl = US"";
501
502 if (smtp_use_pipelining &&
503 (Ustrcmp(smtp_command, "MAIL") == 0 ||
504 Ustrcmp(smtp_command, "RCPT") == 0 ||
505 Ustrcmp(smtp_command, "DATA") == 0))
506 pl = US"pipelined ";
507
508 *yield = '4'; /* Default setting is to give a temporary error */
509
510 /* Handle response timeout */
511
512 if (*errno_value == ETIMEDOUT)
513 {
514 *message = US string_sprintf("SMTP timeout after %s%s",
515 pl, smtp_command);
516 if (transport_count > 0)
517 *message = US string_sprintf("%s (%d bytes written)", *message,
518 transport_count);
519 return FALSE;
520 }
521
522 /* Handle malformed SMTP response */
523
524 if (*errno_value == ERRNO_SMTPFORMAT)
525 {
526 uschar *malfresp = string_printing(buffer);
527 while (isspace(*malfresp)) malfresp++;
528 *message = *malfresp == 0
529 ? string_sprintf("Malformed SMTP reply (an empty line) "
530 "in response to %s%s", pl, smtp_command)
531 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
532 pl, smtp_command, malfresp);
533 return FALSE;
534 }
535
536 /* Handle a failed filter process error; can't send QUIT as we mustn't
537 end the DATA. */
538
539 if (*errno_value == ERRNO_FILTER_FAIL)
540 {
541 *message = US string_sprintf("transport filter process failed (%d)%s",
542 more_errno,
543 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
544 return FALSE;
545 }
546
547 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
548 end the DATA. */
549
550 if (*errno_value == ERRNO_CHHEADER_FAIL)
551 {
552 *message =
553 US string_sprintf("failed to expand headers_add or headers_remove: %s",
554 expand_string_message);
555 return FALSE;
556 }
557
558 /* Handle failure to write a complete data block */
559
560 if (*errno_value == ERRNO_WRITEINCOMPLETE)
561 {
562 *message = US string_sprintf("failed to write a data block");
563 return FALSE;
564 }
565
566 /* Handle error responses from the remote mailer. */
567
568 if (buffer[0] != 0)
569 {
570 uschar *s = string_printing(buffer);
571 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
572 "%s", pl, smtp_command, s);
573 *pass_message = TRUE;
574 *yield = buffer[0];
575 return TRUE;
576 }
577
578 /* No data was read. If there is no errno, this must be the EOF (i.e.
579 connection closed) case, which causes deferral. An explicit connection reset
580 error has the same effect. Otherwise, put the host's identity in the message,
581 leaving the errno value to be interpreted as well. In all cases, we have to
582 assume the connection is now dead. */
583
584 if (*errno_value == 0 || *errno_value == ECONNRESET)
585 {
586 *errno_value = ERRNO_SMTPCLOSED;
587 *message = US string_sprintf("Remote host closed connection "
588 "in response to %s%s", pl, smtp_command);
589 }
590 else *message = US string_sprintf("%s [%s]", host->name, host->address);
591
592 return FALSE;
593 }
594
595
596
597 /*************************************************
598 * Write error message to logs *
599 *************************************************/
600
601 /* This writes to the main log and to the message log.
602
603 Arguments:
604 addr the address item containing error information
605 host the current host
606
607 Returns: nothing
608 */
609
610 static void
611 write_logs(address_item *addr, host_item *host)
612 {
613 uschar * message = string_sprintf("H=%s [%s]", host->name, host->address);
614
615 if (addr->message)
616 {
617 message = string_sprintf("%s: %s", message, addr->message);
618 if (addr->basic_errno > 0)
619 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
620 log_write(0, LOG_MAIN, "%s", message);
621 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
622 }
623 else
624 {
625 if (log_extra_selector & LX_outgoing_port)
626 message = string_sprintf("%s:%d", message,
627 host->port == PORT_NONE ? 25 : host->port);
628 log_write(0, LOG_MAIN, "%s %s", message, strerror(addr->basic_errno));
629 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), message,
630 strerror(addr->basic_errno));
631 }
632 }
633
634 static void
635 msglog_line(host_item * host, uschar * message)
636 {
637 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
638 host->name, host->address, message);
639 }
640
641
642
643 #ifdef EXPERIMENTAL_EVENT
644 /*************************************************
645 * Post-defer action *
646 *************************************************/
647
648 /* This expands an arbitrary per-transport string.
649 It might, for example, be used to write to the database log.
650
651 Arguments:
652 addr the address item containing error information
653 host the current host
654
655 Returns: nothing
656 */
657
658 static void
659 deferred_event_raise(address_item *addr, host_item *host)
660 {
661 uschar * action = addr->transport->event_action;
662 uschar * save_domain;
663 uschar * save_local;
664
665 if (!action)
666 return;
667
668 save_domain = deliver_domain;
669 save_local = deliver_localpart;
670
671 /*XXX would ip & port already be set up? */
672 deliver_host_address = string_copy(host->address);
673 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
674 event_defer_errno = addr->basic_errno;
675
676 router_name = addr->router->name;
677 transport_name = addr->transport->name;
678 deliver_domain = addr->domain;
679 deliver_localpart = addr->local_part;
680
681 (void) event_raise(action, US"msg:host:defer",
682 addr->message
683 ? addr->basic_errno > 0
684 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
685 : string_copy(addr->message)
686 : addr->basic_errno > 0
687 ? string_copy(US strerror(addr->basic_errno))
688 : NULL);
689
690 deliver_localpart = save_local;
691 deliver_domain = save_domain;
692 router_name = transport_name = NULL;
693 }
694 #endif
695
696
697
698 /*************************************************
699 * Synchronize SMTP responses *
700 *************************************************/
701
702 /* This function is called from smtp_deliver() to receive SMTP responses from
703 the server, and match them up with the commands to which they relate. When
704 PIPELINING is not in use, this function is called after every command, and is
705 therefore somewhat over-engineered, but it is simpler to use a single scheme
706 that works both with and without PIPELINING instead of having two separate sets
707 of code.
708
709 The set of commands that are buffered up with pipelining may start with MAIL
710 and may end with DATA; in between are RCPT commands that correspond to the
711 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
712 etc.) are never buffered.
713
714 Errors after MAIL or DATA abort the whole process leaving the response in the
715 buffer. After MAIL, pending responses are flushed, and the original command is
716 re-instated in big_buffer for error messages. For RCPT commands, the remote is
717 permitted to reject some recipient addresses while accepting others. However
718 certain errors clearly abort the whole process. Set the value in
719 transport_return to PENDING_OK if the address is accepted. If there is a
720 subsequent general error, it will get reset accordingly. If not, it will get
721 converted to OK at the end.
722
723 Arguments:
724 addrlist the complete address list
725 include_affixes TRUE if affixes include in RCPT
726 sync_addr ptr to the ptr of the one to start scanning at (updated)
727 host the host we are connected to
728 count the number of responses to read
729 address_retry_
730 include_sender true if 4xx retry is to include the sender it its key
731 pending_MAIL true if the first response is for MAIL
732 pending_DATA 0 if last command sent was not DATA
733 +1 if previously had a good recipient
734 -1 if not previously had a good recipient
735 inblock incoming SMTP block
736 timeout timeout value
737 buffer buffer for reading response
738 buffsize size of buffer
739
740 Returns: 3 if at least one address had 2xx and one had 5xx
741 2 if at least one address had 5xx but none had 2xx
742 1 if at least one host had a 2xx response, but none had 5xx
743 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
744 -1 timeout while reading RCPT response
745 -2 I/O or other non-response error for RCPT
746 -3 DATA or MAIL failed - errno and buffer set
747 */
748
749 static int
750 sync_responses(address_item *addrlist, BOOL include_affixes,
751 address_item **sync_addr, host_item *host, int count,
752 BOOL address_retry_include_sender, BOOL pending_MAIL,
753 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
754 int buffsize)
755 {
756 address_item *addr = *sync_addr;
757 int yield = 0;
758
759 /* Handle the response for a MAIL command. On error, reinstate the original
760 command in big_buffer for error message use, and flush any further pending
761 responses before returning, except after I/O errors and timeouts. */
762
763 if (pending_MAIL)
764 {
765 count--;
766 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
767 {
768 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
769 if (errno == 0 && buffer[0] != 0)
770 {
771 uschar flushbuffer[4096];
772 int save_errno = 0;
773 if (buffer[0] == '4')
774 {
775 save_errno = ERRNO_MAIL4XX;
776 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
777 }
778 while (count-- > 0)
779 {
780 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
781 '2', timeout)
782 && (errno != 0 || flushbuffer[0] == 0))
783 break;
784 }
785 errno = save_errno;
786 }
787
788 if (pending_DATA) count--; /* Number of RCPT responses to come */
789 while (count-- > 0) /* Mark any pending addrs with the host used */
790 {
791 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
792 addr->host_used = host;
793 addr = addr->next;
794 }
795 return -3;
796 }
797 }
798
799 if (pending_DATA) count--; /* Number of RCPT responses to come */
800
801 /* Read and handle the required number of RCPT responses, matching each one up
802 with an address by scanning for the next address whose status is PENDING_DEFER.
803 */
804
805 while (count-- > 0)
806 {
807 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
808
809 /* The address was accepted */
810 addr->host_used = host;
811
812 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
813 {
814 yield |= 1;
815 addr->transport_return = PENDING_OK;
816
817 /* If af_dr_retry_exists is set, there was a routing delay on this address;
818 ensure that any address-specific retry record is expunged. We do this both
819 for the basic key and for the version that also includes the sender. */
820
821 if (testflag(addr, af_dr_retry_exists))
822 {
823 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
824 sender_address);
825 retry_add_item(addr, altkey, rf_delete);
826 retry_add_item(addr, addr->address_retry_key, rf_delete);
827 }
828 }
829
830 /* Timeout while reading the response */
831
832 else if (errno == ETIMEDOUT)
833 {
834 int save_errno = errno;
835 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
836 transport_rcpt_address(addr, include_affixes));
837 set_errno(addrlist, save_errno, message, DEFER, FALSE, NULL);
838 retry_add_item(addr, addr->address_retry_key, 0);
839 update_waiting = FALSE;
840 return -1;
841 }
842
843 /* Handle other errors in obtaining an SMTP response by returning -1. This
844 will cause all the addresses to be deferred. Restore the SMTP command in
845 big_buffer for which we are checking the response, so the error message
846 makes sense. */
847
848 else if (errno != 0 || buffer[0] == 0)
849 {
850 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
851 transport_rcpt_address(addr, include_affixes));
852 return -2;
853 }
854
855 /* Handle SMTP permanent and temporary response codes. */
856
857 else
858 {
859 addr->message =
860 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
861 "%s", transport_rcpt_address(addr, include_affixes),
862 string_printing(buffer));
863 setflag(addr, af_pass_message);
864 msglog_line(host, addr->message);
865
866 /* The response was 5xx */
867
868 if (buffer[0] == '5')
869 {
870 addr->transport_return = FAIL;
871 yield |= 2;
872 }
873
874 /* The response was 4xx */
875
876 else
877 {
878 addr->transport_return = DEFER;
879 addr->basic_errno = ERRNO_RCPT4XX;
880 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
881
882 /* Log temporary errors if there are more hosts to be tried.
883 If not, log this last one in the == line. */
884
885 if (host->next)
886 log_write(0, LOG_MAIN, "H=%s [%s]: %s", host->name, host->address, addr->message);
887
888 /* Do not put this message on the list of those waiting for specific
889 hosts, as otherwise it is likely to be tried too often. */
890
891 update_waiting = FALSE;
892
893 /* Add a retry item for the address so that it doesn't get tried again
894 too soon. If address_retry_include_sender is true, add the sender address
895 to the retry key. */
896
897 if (address_retry_include_sender)
898 {
899 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
900 sender_address);
901 retry_add_item(addr, altkey, 0);
902 }
903 else retry_add_item(addr, addr->address_retry_key, 0);
904 }
905 }
906 } /* Loop for next RCPT response */
907
908 /* Update where to start at for the next block of responses, unless we
909 have already handled all the addresses. */
910
911 if (addr != NULL) *sync_addr = addr->next;
912
913 /* Handle a response to DATA. If we have not had any good recipients, either
914 previously or in this block, the response is ignored. */
915
916 if (pending_DATA != 0 &&
917 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
918 {
919 int code;
920 uschar *msg;
921 BOOL pass_message;
922 if (pending_DATA > 0 || (yield & 1) != 0)
923 {
924 if (errno == 0 && buffer[0] == '4')
925 {
926 errno = ERRNO_DATA4XX;
927 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
928 }
929 return -3;
930 }
931 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
932 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
933 "is in use and there were no good recipients\n", msg);
934 }
935
936 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
937 present) received 3xx. If any RCPTs were handled and yielded anything other
938 than 4xx, yield will be set non-zero. */
939
940 return yield;
941 }
942
943
944
945 /* Do the client side of smtp-level authentication */
946 /*
947 Arguments:
948 buffer EHLO response from server (gets overwritten)
949 addrlist chain of potential addresses to deliver
950 host host to deliver to
951 ob transport options
952 ibp, obp comms channel control blocks
953
954 Returns:
955 OK Success, or failed (but not required): global "smtp_authenticated" set
956 DEFER Failed authentication (and was required)
957 ERROR Internal problem
958
959 FAIL_SEND Failed communications - transmit
960 FAIL - response
961 */
962
963 int
964 smtp_auth(uschar *buffer, unsigned bufsize, address_item *addrlist, host_item *host,
965 smtp_transport_options_block *ob, BOOL is_esmtp,
966 smtp_inblock *ibp, smtp_outblock *obp)
967 {
968 int require_auth;
969 uschar *fail_reason = US"server did not advertise AUTH support";
970
971 smtp_authenticated = FALSE;
972 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
973 require_auth = verify_check_given_host(&ob->hosts_require_auth, host);
974
975 if (is_esmtp && !regex_AUTH) regex_AUTH =
976 regex_must_compile(US"\\n250[\\s\\-]AUTH\\s+([\\-\\w\\s]+)(?:\\n|$)",
977 FALSE, TRUE);
978
979 if (is_esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
980 {
981 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
982 expand_nmax = -1; /* reset */
983
984 /* Must not do this check until after we have saved the result of the
985 regex match above. */
986
987 if (require_auth == OK ||
988 verify_check_given_host(&ob->hosts_try_auth, host) == OK)
989 {
990 auth_instance *au;
991 fail_reason = US"no common mechanisms were found";
992
993 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
994
995 /* Scan the configured authenticators looking for one which is configured
996 for use as a client, which is not suppressed by client_condition, and
997 whose name matches an authentication mechanism supported by the server.
998 If one is found, attempt to authenticate by calling its client function.
999 */
1000
1001 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1002 {
1003 uschar *p = names;
1004 if (!au->client ||
1005 (au->client_condition != NULL &&
1006 !expand_check_condition(au->client_condition, au->name,
1007 US"client authenticator")))
1008 {
1009 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1010 au->name,
1011 (au->client)? "client_condition is false" :
1012 "not configured as a client");
1013 continue;
1014 }
1015
1016 /* Loop to scan supported server mechanisms */
1017
1018 while (*p != 0)
1019 {
1020 int rc;
1021 int len = Ustrlen(au->public_name);
1022 while (isspace(*p)) p++;
1023
1024 if (strncmpic(au->public_name, p, len) != 0 ||
1025 (p[len] != 0 && !isspace(p[len])))
1026 {
1027 while (*p != 0 && !isspace(*p)) p++;
1028 continue;
1029 }
1030
1031 /* Found data for a listed mechanism. Call its client entry. Set
1032 a flag in the outblock so that data is overwritten after sending so
1033 that reflections don't show it. */
1034
1035 fail_reason = US"authentication attempt(s) failed";
1036 obp->authenticating = TRUE;
1037 rc = (au->info->clientcode)(au, ibp, obp,
1038 ob->command_timeout, buffer, bufsize);
1039 obp->authenticating = FALSE;
1040 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1041 au->name, rc);
1042
1043 /* A temporary authentication failure must hold up delivery to
1044 this host. After a permanent authentication failure, we carry on
1045 to try other authentication methods. If all fail hard, try to
1046 deliver the message unauthenticated unless require_auth was set. */
1047
1048 switch(rc)
1049 {
1050 case OK:
1051 smtp_authenticated = TRUE; /* stops the outer loop */
1052 client_authenticator = au->name;
1053 if (au->set_client_id != NULL)
1054 client_authenticated_id = expand_string(au->set_client_id);
1055 break;
1056
1057 /* Failure after writing a command */
1058
1059 case FAIL_SEND:
1060 return FAIL_SEND;
1061
1062 /* Failure after reading a response */
1063
1064 case FAIL:
1065 if (errno != 0 || buffer[0] != '5') return FAIL;
1066 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1067 au->name, host->name, host->address, buffer);
1068 break;
1069
1070 /* Failure by some other means. In effect, the authenticator
1071 decided it wasn't prepared to handle this case. Typically this
1072 is the result of "fail" in an expansion string. Do we need to
1073 log anything here? Feb 2006: a message is now put in the buffer
1074 if logging is required. */
1075
1076 case CANCELLED:
1077 if (*buffer != 0)
1078 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1079 "authentication H=%s [%s] %s", au->name, host->name,
1080 host->address, buffer);
1081 break;
1082
1083 /* Internal problem, message in buffer. */
1084
1085 case ERROR:
1086 set_errno(addrlist, 0, string_copy(buffer), DEFER, FALSE, NULL);
1087 return ERROR;
1088 }
1089
1090 break; /* If not authenticated, try next authenticator */
1091 } /* Loop for scanning supported server mechanisms */
1092 } /* Loop for further authenticators */
1093 }
1094 }
1095
1096 /* If we haven't authenticated, but are required to, give up. */
1097
1098 if (require_auth == OK && !smtp_authenticated)
1099 {
1100 set_errno(addrlist, ERRNO_AUTHFAIL,
1101 string_sprintf("authentication required but %s", fail_reason), DEFER,
1102 FALSE, NULL);
1103 return DEFER;
1104 }
1105
1106 return OK;
1107 }
1108
1109
1110 /* Construct AUTH appendix string for MAIL TO */
1111 /*
1112 Arguments
1113 buffer to build string
1114 addrlist chain of potential addresses to deliver
1115 ob transport options
1116
1117 Globals smtp_authenticated
1118 client_authenticated_sender
1119 Return True on error, otherwise buffer has (possibly empty) terminated string
1120 */
1121
1122 BOOL
1123 smtp_mail_auth_str(uschar *buffer, unsigned bufsize, address_item *addrlist,
1124 smtp_transport_options_block *ob)
1125 {
1126 uschar *local_authenticated_sender = authenticated_sender;
1127
1128 #ifdef notdef
1129 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n", authenticated_sender, ob->authenticated_sender, smtp_authenticated?"Y":"N");
1130 #endif
1131
1132 if (ob->authenticated_sender != NULL)
1133 {
1134 uschar *new = expand_string(ob->authenticated_sender);
1135 if (new == NULL)
1136 {
1137 if (!expand_string_forcedfail)
1138 {
1139 uschar *message = string_sprintf("failed to expand "
1140 "authenticated_sender: %s", expand_string_message);
1141 set_errno(addrlist, 0, message, DEFER, FALSE, NULL);
1142 return TRUE;
1143 }
1144 }
1145 else if (new[0] != 0) local_authenticated_sender = new;
1146 }
1147
1148 /* Add the authenticated sender address if present */
1149
1150 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1151 local_authenticated_sender != NULL)
1152 {
1153 string_format(buffer, bufsize, " AUTH=%s",
1154 auth_xtextencode(local_authenticated_sender,
1155 Ustrlen(local_authenticated_sender)));
1156 client_authenticated_sender = string_copy(local_authenticated_sender);
1157 }
1158 else
1159 *buffer= 0;
1160
1161 return FALSE;
1162 }
1163
1164
1165
1166 #ifdef EXPERIMENTAL_DANE
1167 int
1168 tlsa_lookup(const host_item * host, dns_answer * dnsa,
1169 BOOL dane_required, BOOL * dane)
1170 {
1171 /* move this out to host.c given the similarity to dns_lookup() ? */
1172 uschar buffer[300];
1173 uschar * fullname = buffer;
1174
1175 /* TLSA lookup string */
1176 (void)sprintf(CS buffer, "_%d._tcp.%.256s", host->port, host->name);
1177
1178 switch (dns_lookup(dnsa, buffer, T_TLSA, &fullname))
1179 {
1180 case DNS_AGAIN:
1181 return DEFER; /* just defer this TLS'd conn */
1182
1183 default:
1184 case DNS_FAIL:
1185 if (dane_required)
1186 {
1187 log_write(0, LOG_MAIN, "DANE error: TLSA lookup failed");
1188 return FAIL;
1189 }
1190 break;
1191
1192 case DNS_SUCCEED:
1193 if (!dns_is_secure(dnsa))
1194 {
1195 log_write(0, LOG_MAIN, "DANE error: TLSA lookup not DNSSEC");
1196 return DEFER;
1197 }
1198 *dane = TRUE;
1199 break;
1200 }
1201 return OK;
1202 }
1203 #endif
1204
1205
1206 /*************************************************
1207 * Deliver address list to given host *
1208 *************************************************/
1209
1210 /* If continue_hostname is not null, we get here only when continuing to
1211 deliver down an existing channel. The channel was passed as the standard
1212 input. TLS is never active on a passed channel; the previous process always
1213 closes it down before passing the connection on.
1214
1215 Otherwise, we have to make a connection to the remote host, and do the
1216 initial protocol exchange.
1217
1218 When running as an MUA wrapper, if the sender or any recipient is rejected,
1219 temporarily or permanently, we force failure for all recipients.
1220
1221 Arguments:
1222 addrlist chain of potential addresses to deliver; only those whose
1223 transport_return field is set to PENDING_DEFER are currently
1224 being processed; others should be skipped - they have either
1225 been delivered to an earlier host or IP address, or been
1226 failed by one of them.
1227 host host to deliver to
1228 host_af AF_INET or AF_INET6
1229 port default TCP/IP port to use, in host byte order
1230 interface interface to bind to, or NULL
1231 tblock transport instance block
1232 message_defer set TRUE if yield is OK, but all addresses were deferred
1233 because of a non-recipient, non-host failure, that is, a
1234 4xx response to MAIL FROM, DATA, or ".". This is a defer
1235 that is specific to the message.
1236 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1237 a second attempt after TLS initialization fails
1238
1239 Returns: OK - the connection was made and the delivery attempted;
1240 the result for each address is in its data block.
1241 DEFER - the connection could not be made, or something failed
1242 while setting up the SMTP session, or there was a
1243 non-message-specific error, such as a timeout.
1244 ERROR - a filter command is specified for this transport,
1245 and there was a problem setting it up; OR helo_data
1246 or add_headers or authenticated_sender is specified
1247 for this transport, and the string failed to expand
1248 */
1249
1250 static int
1251 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
1252 uschar *interface, transport_instance *tblock,
1253 BOOL *message_defer, BOOL suppress_tls)
1254 {
1255 address_item *addr;
1256 address_item *sync_addr;
1257 address_item *first_addr = addrlist;
1258 int yield = OK;
1259 int address_count;
1260 int save_errno;
1261 int rc;
1262 time_t start_delivery_time = time(NULL);
1263 smtp_transport_options_block *ob =
1264 (smtp_transport_options_block *)(tblock->options_block);
1265 BOOL lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
1266 BOOL smtps = strcmpic(ob->protocol, US"smtps") == 0;
1267 BOOL ok = FALSE;
1268 BOOL send_rset = TRUE;
1269 BOOL send_quit = TRUE;
1270 BOOL setting_up = TRUE;
1271 BOOL completed_address = FALSE;
1272 BOOL esmtp = TRUE;
1273 BOOL pending_MAIL;
1274 BOOL pass_message = FALSE;
1275 #ifndef DISABLE_PRDR
1276 BOOL prdr_offered = FALSE;
1277 BOOL prdr_active;
1278 #endif
1279 BOOL dsn_all_lasthop = TRUE;
1280 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1281 BOOL dane = FALSE;
1282 dns_answer tlsa_dnsa;
1283 #endif
1284 smtp_inblock inblock;
1285 smtp_outblock outblock;
1286 int max_rcpt = tblock->max_addresses;
1287 uschar *igquotstr = US"";
1288 uschar *helo_data = NULL;
1289 uschar *message = NULL;
1290 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
1291 uschar *p;
1292 uschar buffer[4096];
1293 uschar inbuffer[4096];
1294 uschar outbuffer[4096];
1295
1296 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
1297
1298 *message_defer = FALSE;
1299 smtp_command = US"initial connection";
1300 if (max_rcpt == 0) max_rcpt = 999999;
1301
1302 /* Set up the buffer for reading SMTP response packets. */
1303
1304 inblock.buffer = inbuffer;
1305 inblock.buffersize = sizeof(inbuffer);
1306 inblock.ptr = inbuffer;
1307 inblock.ptrend = inbuffer;
1308
1309 /* Set up the buffer for holding SMTP commands while pipelining */
1310
1311 outblock.buffer = outbuffer;
1312 outblock.buffersize = sizeof(outbuffer);
1313 outblock.ptr = outbuffer;
1314 outblock.cmd_count = 0;
1315 outblock.authenticating = FALSE;
1316
1317 /* Reset the parameters of a TLS session. */
1318
1319 tls_out.bits = 0;
1320 tls_out.cipher = NULL; /* the one we may use for this transport */
1321 tls_out.ourcert = NULL;
1322 tls_out.peercert = NULL;
1323 tls_out.peerdn = NULL;
1324 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1325 tls_out.sni = NULL;
1326 #endif
1327 tls_out.ocsp = OCSP_NOT_REQ;
1328
1329 /* Flip the legacy TLS-related variables over to the outbound set in case
1330 they're used in the context of the transport. Don't bother resetting
1331 afterward as we're in a subprocess. */
1332
1333 tls_modify_variables(&tls_out);
1334
1335 #ifndef SUPPORT_TLS
1336 if (smtps)
1337 {
1338 set_errno(addrlist, 0, US"TLS support not available", DEFER, FALSE, NULL);
1339 return ERROR;
1340 }
1341 #endif
1342
1343 /* Make a connection to the host if this isn't a continued delivery, and handle
1344 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
1345 specially so they can be identified for retries. */
1346
1347 if (continue_hostname == NULL)
1348 {
1349 /* This puts port into host->port */
1350 inblock.sock = outblock.sock =
1351 smtp_connect(host, host_af, port, interface, ob->connect_timeout,
1352 ob->keepalive, ob->dscp
1353 #ifdef EXPERIMENTAL_EVENT
1354 , tblock->event_action
1355 #endif
1356 );
1357
1358 if (inblock.sock < 0)
1359 {
1360 set_errno(addrlist, (errno == ETIMEDOUT)? ERRNO_CONNECTTIMEOUT : errno,
1361 NULL, DEFER, FALSE, NULL);
1362 return DEFER;
1363 }
1364
1365 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1366 {
1367 BOOL dane_required;
1368
1369 tls_out.dane_verified = FALSE;
1370 tls_out.tlsa_usage = 0;
1371
1372 dane_required = verify_check_given_host(&ob->hosts_require_dane, host) == OK;
1373
1374 if (host->dnssec == DS_YES)
1375 {
1376 if( dane_required
1377 || verify_check_given_host(&ob->hosts_try_dane, host) == OK
1378 )
1379 if ((rc = tlsa_lookup(host, &tlsa_dnsa, dane_required, &dane)) != OK)
1380 return rc;
1381 }
1382 else if (dane_required)
1383 {
1384 log_write(0, LOG_MAIN, "DANE error: %s lookup not DNSSEC", host->name);
1385 return FAIL;
1386 }
1387
1388 if (dane)
1389 ob->tls_tempfail_tryclear = FALSE;
1390 }
1391 #endif /*DANE*/
1392
1393 /* Expand the greeting message while waiting for the initial response. (Makes
1394 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1395 delayed till here so that $sending_interface and $sending_port are set. */
1396
1397 helo_data = expand_string(ob->helo_data);
1398
1399 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1400 is nevertheless a reasonably clean way of programming this kind of logic,
1401 where you want to escape on any error. */
1402
1403 if (!smtps)
1404 {
1405 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1406 ob->command_timeout)) goto RESPONSE_FAILED;
1407
1408 #ifdef EXPERIMENTAL_EVENT
1409 {
1410 uschar * s;
1411 lookup_dnssec_authenticated = host->dnssec==DS_YES ? US"yes"
1412 : host->dnssec==DS_NO ? US"no" : NULL;
1413 s = event_raise(tblock->event_action, US"smtp:connect", buffer);
1414 if (s)
1415 {
1416 set_errno(addrlist, 0,
1417 string_sprintf("deferred by smtp:connect event expansion: %s", s),
1418 DEFER, FALSE, NULL);
1419 yield = DEFER;
1420 goto SEND_QUIT;
1421 }
1422 }
1423 #endif
1424
1425 /* Now check if the helo_data expansion went well, and sign off cleanly if
1426 it didn't. */
1427
1428 if (helo_data == NULL)
1429 {
1430 uschar *message = string_sprintf("failed to expand helo_data: %s",
1431 expand_string_message);
1432 set_errno(addrlist, 0, message, DEFER, FALSE, NULL);
1433 yield = DEFER;
1434 goto SEND_QUIT;
1435 }
1436 }
1437
1438 /** Debugging without sending a message
1439 addrlist->transport_return = DEFER;
1440 goto SEND_QUIT;
1441 **/
1442
1443 /* Errors that occur after this point follow an SMTP command, which is
1444 left in big_buffer by smtp_write_command() for use in error messages. */
1445
1446 smtp_command = big_buffer;
1447
1448 /* Tell the remote who we are...
1449
1450 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1451 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1452 greeting is of this form. The assumption was that the far end supports it
1453 properly... but experience shows that there are some that give 5xx responses,
1454 even though the banner includes "ESMTP" (there's a bloody-minded one that
1455 says "ESMTP not spoken here"). Cope with that case.
1456
1457 September 2000: Time has passed, and it seems reasonable now to always send
1458 EHLO at the start. It is also convenient to make the change while installing
1459 the TLS stuff.
1460
1461 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1462 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1463 would be no way to send out the mails, so there is now a host list
1464 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1465 PIPELINING problem as well. Maybe it can also be useful to cure other
1466 problems with broken servers.
1467
1468 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1469 Then somebody tried it with a Microsoft mailer... It seems that all other
1470 mailers use upper case for some reason (the RFC is quite clear about case
1471 independence) so, for peace of mind, I gave in. */
1472
1473 esmtp = verify_check_given_host(&ob->hosts_avoid_esmtp, host) != OK;
1474
1475 /* Alas; be careful, since this goto is not an error-out, so conceivably
1476 we might set data between here and the target which we assume to exist
1477 and be usable. I can see this coming back to bite us. */
1478 #ifdef SUPPORT_TLS
1479 if (smtps)
1480 {
1481 tls_offered = TRUE;
1482 suppress_tls = FALSE;
1483 ob->tls_tempfail_tryclear = FALSE;
1484 smtp_command = US"SSL-on-connect";
1485 goto TLS_NEGOTIATE;
1486 }
1487 #endif
1488
1489 if (esmtp)
1490 {
1491 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1492 lmtp? "LHLO" : "EHLO", helo_data) < 0)
1493 goto SEND_FAILED;
1494 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1495 ob->command_timeout))
1496 {
1497 if (errno != 0 || buffer[0] == 0 || lmtp) goto RESPONSE_FAILED;
1498 esmtp = FALSE;
1499 }
1500 }
1501 else
1502 {
1503 DEBUG(D_transport)
1504 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1505 }
1506
1507 if (!esmtp)
1508 {
1509 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1510 goto SEND_FAILED;
1511 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1512 ob->command_timeout)) goto RESPONSE_FAILED;
1513 }
1514
1515 /* Set IGNOREQUOTA if the response to LHLO specifies support and the
1516 lmtp_ignore_quota option was set. */
1517
1518 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1519 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1520 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1521
1522 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1523
1524 #ifdef SUPPORT_TLS
1525 tls_offered = esmtp &&
1526 pcre_exec(regex_STARTTLS, NULL, CS buffer, Ustrlen(buffer), 0,
1527 PCRE_EOPT, NULL, 0) >= 0;
1528 #endif
1529
1530 #ifndef DISABLE_PRDR
1531 prdr_offered = esmtp
1532 && pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(buffer), 0,
1533 PCRE_EOPT, NULL, 0) >= 0
1534 && verify_check_given_host(&ob->hosts_try_prdr, host) == OK;
1535
1536 if (prdr_offered)
1537 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1538 #endif
1539 }
1540
1541 /* For continuing deliveries down the same channel, the socket is the standard
1542 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1543 below). Set up the pointer to where subsequent commands will be left, for
1544 error messages. Note that smtp_use_size and smtp_use_pipelining will have been
1545 set from the command line if they were set in the process that passed the
1546 connection on. */
1547
1548 else
1549 {
1550 inblock.sock = outblock.sock = fileno(stdin);
1551 smtp_command = big_buffer;
1552 host->port = port; /* Record the port that was used */
1553 }
1554
1555 /* If TLS is available on this connection, whether continued or not, attempt to
1556 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1557 send another EHLO - the server may give a different answer in secure mode. We
1558 use a separate buffer for reading the response to STARTTLS so that if it is
1559 negative, the original EHLO data is available for subsequent analysis, should
1560 the client not be required to use TLS. If the response is bad, copy the buffer
1561 for error analysis. */
1562
1563 #ifdef SUPPORT_TLS
1564 if ( tls_offered
1565 && !suppress_tls
1566 && verify_check_given_host(&ob->hosts_avoid_tls, host) != OK)
1567 {
1568 uschar buffer2[4096];
1569 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1570 goto SEND_FAILED;
1571
1572 /* If there is an I/O error, transmission of this message is deferred. If
1573 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1574 false, we also defer. However, if there is a temporary rejection of STARTTLS
1575 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1576 STARTTLS, we carry on. This means we will try to send the message in clear,
1577 unless the host is in hosts_require_tls (tested below). */
1578
1579 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1580 ob->command_timeout))
1581 {
1582 if (errno != 0 || buffer2[0] == 0 ||
1583 (buffer2[0] == '4' && !ob->tls_tempfail_tryclear))
1584 {
1585 Ustrncpy(buffer, buffer2, sizeof(buffer));
1586 goto RESPONSE_FAILED;
1587 }
1588 }
1589
1590 /* STARTTLS accepted: try to negotiate a TLS session. */
1591
1592 else
1593 TLS_NEGOTIATE:
1594 {
1595 int rc = tls_client_start(inblock.sock, host, addrlist, tblock
1596 # ifdef EXPERIMENTAL_DANE
1597 , dane ? &tlsa_dnsa : NULL
1598 # endif
1599 );
1600
1601 /* TLS negotiation failed; give an error. From outside, this function may
1602 be called again to try in clear on a new connection, if the options permit
1603 it for this host. */
1604
1605 if (rc != OK)
1606 {
1607 save_errno = ERRNO_TLSFAILURE;
1608 message = US"failure while setting up TLS session";
1609 send_quit = FALSE;
1610 goto TLS_FAILED;
1611 }
1612
1613 /* TLS session is set up */
1614
1615 for (addr = addrlist; addr != NULL; addr = addr->next)
1616 if (addr->transport_return == PENDING_DEFER)
1617 {
1618 addr->cipher = tls_out.cipher;
1619 addr->ourcert = tls_out.ourcert;
1620 addr->peercert = tls_out.peercert;
1621 addr->peerdn = tls_out.peerdn;
1622 addr->ocsp = tls_out.ocsp;
1623 }
1624 }
1625 }
1626
1627 /* if smtps, we'll have smtp_command set to something else; always safe to
1628 reset it here. */
1629 smtp_command = big_buffer;
1630
1631 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1632 helo_data is null, we are dealing with a connection that was passed from
1633 another process, and so we won't have expanded helo_data above. We have to
1634 expand it here. $sending_ip_address and $sending_port are set up right at the
1635 start of the Exim process (in exim.c). */
1636
1637 if (tls_out.active >= 0)
1638 {
1639 char *greeting_cmd;
1640 if (helo_data == NULL)
1641 {
1642 helo_data = expand_string(ob->helo_data);
1643 if (helo_data == NULL)
1644 {
1645 uschar *message = string_sprintf("failed to expand helo_data: %s",
1646 expand_string_message);
1647 set_errno(addrlist, 0, message, DEFER, FALSE, NULL);
1648 yield = DEFER;
1649 goto SEND_QUIT;
1650 }
1651 }
1652
1653 /* For SMTPS we need to wait for the initial OK response. */
1654 if (smtps)
1655 {
1656 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1657 ob->command_timeout)) goto RESPONSE_FAILED;
1658 }
1659
1660 if (esmtp)
1661 greeting_cmd = "EHLO";
1662 else
1663 {
1664 greeting_cmd = "HELO";
1665 DEBUG(D_transport)
1666 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1667 }
1668
1669 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1670 lmtp? "LHLO" : greeting_cmd, helo_data) < 0)
1671 goto SEND_FAILED;
1672 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1673 ob->command_timeout))
1674 goto RESPONSE_FAILED;
1675 }
1676
1677 /* If the host is required to use a secure channel, ensure that we
1678 have one. */
1679
1680 else if (
1681 # ifdef EXPERIMENTAL_DANE
1682 dane ||
1683 # endif
1684 verify_check_given_host(&ob->hosts_require_tls, host) == OK
1685 )
1686 {
1687 save_errno = ERRNO_TLSREQUIRED;
1688 message = string_sprintf("a TLS session is required, but %s",
1689 tls_offered? "an attempt to start TLS failed" :
1690 "the server did not offer TLS support");
1691 goto TLS_FAILED;
1692 }
1693 #endif /*SUPPORT_TLS*/
1694
1695 /* If TLS is active, we have just started it up and re-done the EHLO command,
1696 so its response needs to be analyzed. If TLS is not active and this is a
1697 continued session down a previously-used socket, we haven't just done EHLO, so
1698 we skip this. */
1699
1700 if (continue_hostname == NULL
1701 #ifdef SUPPORT_TLS
1702 || tls_out.active >= 0
1703 #endif
1704 )
1705 {
1706 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
1707 lmtp_ignore_quota option was set. */
1708
1709 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1710 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1711 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1712
1713 /* If the response to EHLO specified support for the SIZE parameter, note
1714 this, provided size_addition is non-negative. */
1715
1716 smtp_use_size = esmtp && ob->size_addition >= 0 &&
1717 pcre_exec(regex_SIZE, NULL, CS buffer, Ustrlen(CS buffer), 0,
1718 PCRE_EOPT, NULL, 0) >= 0;
1719
1720 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
1721 the current host, esmtp will be false, so PIPELINING can never be used. If
1722 the current host matches hosts_avoid_pipelining, don't do it. */
1723
1724 smtp_use_pipelining = esmtp
1725 && verify_check_given_host(&ob->hosts_avoid_pipelining, host) != OK
1726 && pcre_exec(regex_PIPELINING, NULL, CS buffer, Ustrlen(CS buffer), 0,
1727 PCRE_EOPT, NULL, 0) >= 0;
1728
1729 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
1730 smtp_use_pipelining? "" : "not ");
1731
1732 #ifndef DISABLE_PRDR
1733 prdr_offered = esmtp
1734 && pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(CS buffer), 0,
1735 PCRE_EOPT, NULL, 0) >= 0
1736 && verify_check_given_host(&ob->hosts_try_prdr, host) == OK;
1737
1738 if (prdr_offered)
1739 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1740 #endif
1741
1742 /* Note if the server supports DSN */
1743 smtp_use_dsn = esmtp && pcre_exec(regex_DSN, NULL, CS buffer, (int)Ustrlen(CS buffer), 0,
1744 PCRE_EOPT, NULL, 0) >= 0;
1745 DEBUG(D_transport) debug_printf("use_dsn=%d\n", smtp_use_dsn);
1746
1747 /* Note if the response to EHLO specifies support for the AUTH extension.
1748 If it has, check that this host is one we want to authenticate to, and do
1749 the business. The host name and address must be available when the
1750 authenticator's client driver is running. */
1751
1752 switch (yield = smtp_auth(buffer, sizeof(buffer), addrlist, host,
1753 ob, esmtp, &inblock, &outblock))
1754 {
1755 default: goto SEND_QUIT;
1756 case OK: break;
1757 case FAIL_SEND: goto SEND_FAILED;
1758 case FAIL: goto RESPONSE_FAILED;
1759 }
1760 }
1761
1762 /* The setting up of the SMTP call is now complete. Any subsequent errors are
1763 message-specific. */
1764
1765 setting_up = FALSE;
1766
1767 /* If there is a filter command specified for this transport, we can now
1768 set it up. This cannot be done until the identify of the host is known. */
1769
1770 if (tblock->filter_command != NULL)
1771 {
1772 BOOL rc;
1773 uschar buffer[64];
1774 sprintf(CS buffer, "%.50s transport", tblock->name);
1775 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
1776 TRUE, DEFER, addrlist, buffer, NULL);
1777 transport_filter_timeout = tblock->filter_timeout;
1778
1779 /* On failure, copy the error to all addresses, abandon the SMTP call, and
1780 yield ERROR. */
1781
1782 if (!rc)
1783 {
1784 set_errno(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
1785 FALSE, NULL);
1786 yield = ERROR;
1787 goto SEND_QUIT;
1788 }
1789 }
1790
1791
1792 /* For messages that have more than the maximum number of envelope recipients,
1793 we want to send several transactions down the same SMTP connection. (See
1794 comments in deliver.c as to how this reconciles, heuristically, with
1795 remote_max_parallel.) This optimization was added to Exim after the following
1796 code was already working. The simplest way to put it in without disturbing the
1797 code was to use a goto to jump back to this point when there is another
1798 transaction to handle. */
1799
1800 SEND_MESSAGE:
1801 sync_addr = first_addr;
1802 address_count = 0;
1803 ok = FALSE;
1804 send_rset = TRUE;
1805 completed_address = FALSE;
1806
1807
1808 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
1809 qualification, send it, adding something to the message size to allow for
1810 imprecision and things that get added en route. Exim keeps the number of lines
1811 in a message, so we can give an accurate value for the original message, but we
1812 need some additional to handle added headers. (Double "." characters don't get
1813 included in the count.) */
1814
1815 p = buffer;
1816 *p = 0;
1817
1818 if (smtp_use_size)
1819 {
1820 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
1821 while (*p) p++;
1822 }
1823
1824 #ifndef DISABLE_PRDR
1825 prdr_active = FALSE;
1826 if (prdr_offered)
1827 {
1828 for (addr = first_addr; addr; addr = addr->next)
1829 if (addr->transport_return == PENDING_DEFER)
1830 {
1831 for (addr = addr->next; addr; addr = addr->next)
1832 if (addr->transport_return == PENDING_DEFER)
1833 { /* at least two recipients to send */
1834 prdr_active = TRUE;
1835 sprintf(CS p, " PRDR"); p += 5;
1836 break;
1837 }
1838 break;
1839 }
1840 }
1841 #endif
1842
1843 /* check if all addresses have lasthop flag */
1844 /* do not send RET and ENVID if true */
1845 dsn_all_lasthop = TRUE;
1846 for (addr = first_addr;
1847 address_count < max_rcpt && addr != NULL;
1848 addr = addr->next)
1849 if ((addr->dsn_flags & rf_dsnlasthop) != 1)
1850 dsn_all_lasthop = FALSE;
1851
1852 /* Add any DSN flags to the mail command */
1853
1854 if ((smtp_use_dsn) && (dsn_all_lasthop == FALSE))
1855 {
1856 if (dsn_ret == dsn_ret_hdrs)
1857 {
1858 Ustrcpy(p, " RET=HDRS");
1859 while (*p) p++;
1860 }
1861 else if (dsn_ret == dsn_ret_full)
1862 {
1863 Ustrcpy(p, " RET=FULL");
1864 while (*p) p++;
1865 }
1866 if (dsn_envid != NULL)
1867 {
1868 string_format(p, sizeof(buffer) - (p-buffer), " ENVID=%s", dsn_envid);
1869 while (*p) p++;
1870 }
1871 }
1872
1873 /* If an authenticated_sender override has been specified for this transport
1874 instance, expand it. If the expansion is forced to fail, and there was already
1875 an authenticated_sender for this message, the original value will be used.
1876 Other expansion failures are serious. An empty result is ignored, but there is
1877 otherwise no check - this feature is expected to be used with LMTP and other
1878 cases where non-standard addresses (e.g. without domains) might be required. */
1879
1880 if (smtp_mail_auth_str(p, sizeof(buffer) - (p-buffer), addrlist, ob))
1881 {
1882 yield = ERROR;
1883 goto SEND_QUIT;
1884 }
1885
1886 /* From here until we send the DATA command, we can make use of PIPELINING
1887 if the server host supports it. The code has to be able to check the responses
1888 at any point, for when the buffer fills up, so we write it totally generally.
1889 When PIPELINING is off, each command written reports that it has flushed the
1890 buffer. */
1891
1892 pending_MAIL = TRUE; /* The block starts with MAIL */
1893
1894 rc = smtp_write_command(&outblock, smtp_use_pipelining,
1895 "MAIL FROM:<%s>%s\r\n", return_path, buffer);
1896 mail_command = string_copy(big_buffer); /* Save for later error message */
1897
1898 switch(rc)
1899 {
1900 case -1: /* Transmission error */
1901 goto SEND_FAILED;
1902
1903 case +1: /* Block was sent */
1904 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1905 ob->command_timeout))
1906 {
1907 if (errno == 0 && buffer[0] == '4')
1908 {
1909 errno = ERRNO_MAIL4XX;
1910 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1911 }
1912 goto RESPONSE_FAILED;
1913 }
1914 pending_MAIL = FALSE;
1915 break;
1916 }
1917
1918 /* Pass over all the relevant recipient addresses for this host, which are the
1919 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
1920 several before we have to read the responses for those seen so far. This
1921 checking is done by a subroutine because it also needs to be done at the end.
1922 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
1923 the next one if not all are sent.
1924
1925 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
1926 last address because we want to abort if any recipients have any kind of
1927 problem, temporary or permanent. We know that all recipient addresses will have
1928 the PENDING_DEFER status, because only one attempt is ever made, and we know
1929 that max_rcpt will be large, so all addresses will be done at once. */
1930
1931 for (addr = first_addr;
1932 address_count < max_rcpt && addr != NULL;
1933 addr = addr->next)
1934 {
1935 int count;
1936 BOOL no_flush;
1937
1938 addr->dsn_aware = smtp_use_dsn ? dsn_support_yes : dsn_support_no;
1939
1940 if (addr->transport_return != PENDING_DEFER) continue;
1941
1942 address_count++;
1943 no_flush = smtp_use_pipelining && (!mua_wrapper || addr->next != NULL);
1944
1945 /* Add any DSN flags to the rcpt command and add to the sent string */
1946
1947 p = buffer;
1948 *p = 0;
1949
1950 if (smtp_use_dsn && (addr->dsn_flags & rf_dsnlasthop) != 1)
1951 {
1952 if ((addr->dsn_flags & rf_dsnflags) != 0)
1953 {
1954 int i;
1955 BOOL first = TRUE;
1956 Ustrcpy(p, " NOTIFY=");
1957 while (*p) p++;
1958 for (i = 0; i < 4; i++)
1959 if ((addr->dsn_flags & rf_list[i]) != 0)
1960 {
1961 if (!first) *p++ = ',';
1962 first = FALSE;
1963 Ustrcpy(p, rf_names[i]);
1964 while (*p) p++;
1965 }
1966 }
1967
1968 if (addr->dsn_orcpt != NULL)
1969 {
1970 string_format(p, sizeof(buffer) - (p-buffer), " ORCPT=%s",
1971 addr->dsn_orcpt);
1972 while (*p) p++;
1973 }
1974 }
1975
1976 /* Now send the RCPT command, and process outstanding responses when
1977 necessary. After a timeout on RCPT, we just end the function, leaving the
1978 yield as OK, because this error can often mean that there is a problem with
1979 just one address, so we don't want to delay the host. */
1980
1981 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s%s\r\n",
1982 transport_rcpt_address(addr, tblock->rcpt_include_affixes), igquotstr, buffer);
1983
1984 if (count < 0) goto SEND_FAILED;
1985 if (count > 0)
1986 {
1987 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
1988 &sync_addr, host, count, ob->address_retry_include_sender,
1989 pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
1990 sizeof(buffer)))
1991 {
1992 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1993 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1994 break;
1995
1996 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1997 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1998 case 0: /* No 2xx or 5xx, but no probs */
1999 break;
2000
2001 case -1: goto END_OFF; /* Timeout on RCPT */
2002 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
2003 }
2004 pending_MAIL = FALSE; /* Dealt with MAIL */
2005 }
2006 } /* Loop for next address */
2007
2008 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
2009 permanently or temporarily. We should have flushed and synced after the last
2010 RCPT. */
2011
2012 if (mua_wrapper)
2013 {
2014 address_item *badaddr;
2015 for (badaddr = first_addr; badaddr != NULL; badaddr = badaddr->next)
2016 {
2017 if (badaddr->transport_return != PENDING_OK) break;
2018 }
2019 if (badaddr != NULL)
2020 {
2021 set_errno(addrlist, 0, badaddr->message, FAIL,
2022 testflag(badaddr, af_pass_message), NULL);
2023 ok = FALSE;
2024 }
2025 }
2026
2027 /* If ok is TRUE, we know we have got at least one good recipient, and must now
2028 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
2029 have a good recipient buffered up if we are pipelining. We don't want to waste
2030 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
2031 are pipelining. The responses are all handled by sync_responses(). */
2032
2033 if (ok || (smtp_use_pipelining && !mua_wrapper))
2034 {
2035 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
2036 if (count < 0) goto SEND_FAILED;
2037 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
2038 host, count, ob->address_retry_include_sender, pending_MAIL,
2039 ok? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
2040 {
2041 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2042 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2043 break;
2044
2045 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2046 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2047 case 0: break; /* No 2xx or 5xx, but no probs */
2048
2049 case -1: goto END_OFF; /* Timeout on RCPT */
2050 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2051 }
2052 }
2053
2054 /* Save the first address of the next batch. */
2055
2056 first_addr = addr;
2057
2058 /* If there were no good recipients (but otherwise there have been no
2059 problems), just set ok TRUE, since we have handled address-specific errors
2060 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
2061 for handling the SMTP dot-handling protocol, flagging to apply to headers as
2062 well as body. Set the appropriate timeout value to be used for each chunk.
2063 (Haven't been able to make it work using select() for writing yet.) */
2064
2065 if (!ok) ok = TRUE; else
2066 {
2067 sigalrm_seen = FALSE;
2068 transport_write_timeout = ob->data_timeout;
2069 smtp_command = US"sending data block"; /* For error messages */
2070 DEBUG(D_transport|D_v)
2071 debug_printf(" SMTP>> writing message and terminating \".\"\n");
2072 transport_count = 0;
2073
2074 #ifndef DISABLE_DKIM
2075 ok = dkim_transport_write_message(addrlist, inblock.sock,
2076 topt_use_crlf | topt_end_dot | topt_escape_headers |
2077 (tblock->body_only? topt_no_headers : 0) |
2078 (tblock->headers_only? topt_no_body : 0) |
2079 (tblock->return_path_add? topt_add_return_path : 0) |
2080 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
2081 (tblock->envelope_to_add? topt_add_envelope_to : 0),
2082 0, /* No size limit */
2083 tblock->add_headers, tblock->remove_headers,
2084 US".", US"..", /* Escaping strings */
2085 tblock->rewrite_rules, tblock->rewrite_existflags,
2086 ob->dkim_private_key, ob->dkim_domain, ob->dkim_selector,
2087 ob->dkim_canon, ob->dkim_strict, ob->dkim_sign_headers
2088 );
2089 #else
2090 ok = transport_write_message(addrlist, inblock.sock,
2091 topt_use_crlf | topt_end_dot | topt_escape_headers |
2092 (tblock->body_only? topt_no_headers : 0) |
2093 (tblock->headers_only? topt_no_body : 0) |
2094 (tblock->return_path_add? topt_add_return_path : 0) |
2095 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
2096 (tblock->envelope_to_add? topt_add_envelope_to : 0),
2097 0, /* No size limit */
2098 tblock->add_headers, tblock->remove_headers,
2099 US".", US"..", /* Escaping strings */
2100 tblock->rewrite_rules, tblock->rewrite_existflags);
2101 #endif
2102
2103 /* transport_write_message() uses write() because it is called from other
2104 places to write to non-sockets. This means that under some OS (e.g. Solaris)
2105 it can exit with "Broken pipe" as its error. This really means that the
2106 socket got closed at the far end. */
2107
2108 transport_write_timeout = 0; /* for subsequent transports */
2109
2110 /* Failure can either be some kind of I/O disaster (including timeout),
2111 or the failure of a transport filter or the expansion of added headers. */
2112
2113 if (!ok)
2114 {
2115 buffer[0] = 0; /* There hasn't been a response */
2116 goto RESPONSE_FAILED;
2117 }
2118
2119 /* We used to send the terminating "." explicitly here, but because of
2120 buffering effects at both ends of TCP/IP connections, you don't gain
2121 anything by keeping it separate, so it might as well go in the final
2122 data buffer for efficiency. This is now done by setting the topt_end_dot
2123 flag above. */
2124
2125 smtp_command = US"end of data";
2126
2127 #ifndef DISABLE_PRDR
2128 /* For PRDR we optionally get a partial-responses warning
2129 * followed by the individual responses, before going on with
2130 * the overall response. If we don't get the warning then deal
2131 * with per non-PRDR. */
2132 if(prdr_active)
2133 {
2134 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '3',
2135 ob->final_timeout);
2136 if (!ok && errno == 0)
2137 switch(buffer[0])
2138 {
2139 case '2': prdr_active = FALSE;
2140 ok = TRUE;
2141 break;
2142 case '4': errno = ERRNO_DATA4XX;
2143 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2144 break;
2145 }
2146 }
2147 else
2148 #endif
2149
2150 /* For non-PRDR SMTP, we now read a single response that applies to the
2151 whole message. If it is OK, then all the addresses have been delivered. */
2152
2153 if (!lmtp)
2154 {
2155 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2156 ob->final_timeout);
2157 if (!ok && errno == 0 && buffer[0] == '4')
2158 {
2159 errno = ERRNO_DATA4XX;
2160 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2161 }
2162 }
2163
2164 /* For LMTP, we get back a response for every RCPT command that we sent;
2165 some may be accepted and some rejected. For those that get a response, their
2166 status is fixed; any that are accepted have been handed over, even if later
2167 responses crash - at least, that's how I read RFC 2033.
2168
2169 If all went well, mark the recipient addresses as completed, record which
2170 host/IPaddress they were delivered to, and cut out RSET when sending another
2171 message down the same channel. Write the completed addresses to the journal
2172 now so that they are recorded in case there is a crash of hardware or
2173 software before the spool gets updated. Also record the final SMTP
2174 confirmation if needed (for SMTP only). */
2175
2176 if (ok)
2177 {
2178 int flag = '=';
2179 int delivery_time = (int)(time(NULL) - start_delivery_time);
2180 int len;
2181 uschar *conf = NULL;
2182 send_rset = FALSE;
2183
2184 /* Set up confirmation if needed - applies only to SMTP */
2185
2186 if (
2187 #ifndef EXPERIMENTAL_EVENT
2188 (log_extra_selector & LX_smtp_confirmation) != 0 &&
2189 #endif
2190 !lmtp
2191 )
2192 {
2193 uschar *s = string_printing(buffer);
2194 conf = (s == buffer)? (uschar *)string_copy(s) : s;
2195 }
2196
2197 /* Process all transported addresses - for LMTP or PRDR, read a status for
2198 each one. */
2199
2200 for (addr = addrlist; addr != first_addr; addr = addr->next)
2201 {
2202 if (addr->transport_return != PENDING_OK) continue;
2203
2204 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
2205 remaining addresses. Otherwise, it's a return code for just the one
2206 address. For temporary errors, add a retry item for the address so that
2207 it doesn't get tried again too soon. */
2208
2209 #ifndef DISABLE_PRDR
2210 if (lmtp || prdr_active)
2211 #else
2212 if (lmtp)
2213 #endif
2214 {
2215 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2216 ob->final_timeout))
2217 {
2218 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
2219 addr->message = string_sprintf(
2220 #ifndef DISABLE_PRDR
2221 "%s error after %s: %s", prdr_active ? "PRDR":"LMTP",
2222 #else
2223 "LMTP error after %s: %s",
2224 #endif
2225 big_buffer, string_printing(buffer));
2226 setflag(addr, af_pass_message); /* Allow message to go to user */
2227 if (buffer[0] == '5')
2228 addr->transport_return = FAIL;
2229 else
2230 {
2231 errno = ERRNO_DATA4XX;
2232 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2233 addr->transport_return = DEFER;
2234 #ifndef DISABLE_PRDR
2235 if (!prdr_active)
2236 #endif
2237 retry_add_item(addr, addr->address_retry_key, 0);
2238 }
2239 continue;
2240 }
2241 completed_address = TRUE; /* NOW we can set this flag */
2242 if ((log_extra_selector & LX_smtp_confirmation) != 0)
2243 {
2244 uschar *s = string_printing(buffer);
2245 conf = (s == buffer)? (uschar *)string_copy(s) : s;
2246 }
2247 }
2248
2249 /* SMTP, or success return from LMTP for this address. Pass back the
2250 actual host that was used. */
2251
2252 addr->transport_return = OK;
2253 addr->more_errno = delivery_time;
2254 addr->host_used = host;
2255 addr->special_action = flag;
2256 addr->message = conf;
2257 #ifndef DISABLE_PRDR
2258 if (prdr_active) addr->flags |= af_prdr_used;
2259 #endif
2260 flag = '-';
2261
2262 #ifndef DISABLE_PRDR
2263 if (!prdr_active)
2264 #endif
2265 {
2266 /* Update the journal. For homonymic addresses, use the base address plus
2267 the transport name. See lots of comments in deliver.c about the reasons
2268 for the complications when homonyms are involved. Just carry on after
2269 write error, as it may prove possible to update the spool file later. */
2270
2271 if (testflag(addr, af_homonym))
2272 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2273 else
2274 sprintf(CS buffer, "%.500s\n", addr->unique);
2275
2276 DEBUG(D_deliver) debug_printf("journalling %s", buffer);
2277 len = Ustrlen(CS buffer);
2278 if (write(journal_fd, buffer, len) != len)
2279 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2280 "%s: %s", buffer, strerror(errno));
2281 }
2282 }
2283
2284 #ifndef DISABLE_PRDR
2285 if (prdr_active)
2286 {
2287 /* PRDR - get the final, overall response. For any non-success
2288 upgrade all the address statuses. */
2289 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2290 ob->final_timeout);
2291 if (!ok)
2292 {
2293 if(errno == 0 && buffer[0] == '4')
2294 {
2295 errno = ERRNO_DATA4XX;
2296 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2297 }
2298 for (addr = addrlist; addr != first_addr; addr = addr->next)
2299 if (buffer[0] == '5' || addr->transport_return == OK)
2300 addr->transport_return = PENDING_OK; /* allow set_errno action */
2301 goto RESPONSE_FAILED;
2302 }
2303
2304 /* Update the journal, or setup retry. */
2305 for (addr = addrlist; addr != first_addr; addr = addr->next)
2306 if (addr->transport_return == OK)
2307 {
2308 if (testflag(addr, af_homonym))
2309 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2310 else
2311 sprintf(CS buffer, "%.500s\n", addr->unique);
2312
2313 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s", buffer);
2314 len = Ustrlen(CS buffer);
2315 if (write(journal_fd, buffer, len) != len)
2316 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2317 "%s: %s", buffer, strerror(errno));
2318 }
2319 else if (addr->transport_return == DEFER)
2320 retry_add_item(addr, addr->address_retry_key, -2);
2321 }
2322 #endif
2323
2324 /* Ensure the journal file is pushed out to disk. */
2325
2326 if (EXIMfsync(journal_fd) < 0)
2327 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
2328 strerror(errno));
2329 }
2330 }
2331
2332
2333 /* Handle general (not specific to one address) failures here. The value of ok
2334 is used to skip over this code on the falling through case. A timeout causes a
2335 deferral. Other errors may defer or fail according to the response code, and
2336 may set up a special errno value, e.g. after connection chopped, which is
2337 assumed if errno == 0 and there is no text in the buffer. If control reaches
2338 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
2339 the problem is not related to this specific message. */
2340
2341 if (!ok)
2342 {
2343 int code;
2344
2345 RESPONSE_FAILED:
2346 save_errno = errno;
2347 message = NULL;
2348 send_quit = check_response(host, &save_errno, addrlist->more_errno,
2349 buffer, &code, &message, &pass_message);
2350 goto FAILED;
2351
2352 SEND_FAILED:
2353 save_errno = errno;
2354 code = '4';
2355 message = US string_sprintf("send() to %s [%s] failed: %s",
2356 host->name, host->address, strerror(save_errno));
2357 send_quit = FALSE;
2358 goto FAILED;
2359
2360 /* This label is jumped to directly when a TLS negotiation has failed,
2361 or was not done for a host for which it is required. Values will be set
2362 in message and save_errno, and setting_up will always be true. Treat as
2363 a temporary error. */
2364
2365 #ifdef SUPPORT_TLS
2366 TLS_FAILED:
2367 code = '4';
2368 #endif
2369
2370 /* If the failure happened while setting up the call, see if the failure was
2371 a 5xx response (this will either be on connection, or following HELO - a 5xx
2372 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
2373 never going to accept them. For other errors during setting up (timeouts or
2374 whatever), defer all addresses, and yield DEFER, so that the host is not
2375 tried again for a while. */
2376
2377 FAILED:
2378 ok = FALSE; /* For when reached by GOTO */
2379
2380 if (setting_up)
2381 {
2382 if (code == '5')
2383 set_errno(addrlist, save_errno, message, FAIL, pass_message, host);
2384 else
2385 {
2386 set_errno(addrlist, save_errno, message, DEFER, pass_message, host);
2387 yield = DEFER;
2388 }
2389 }
2390
2391 /* We want to handle timeouts after MAIL or "." and loss of connection after
2392 "." specially. They can indicate a problem with the sender address or with
2393 the contents of the message rather than a real error on the connection. These
2394 cases are treated in the same way as a 4xx response. This next bit of code
2395 does the classification. */
2396
2397 else
2398 {
2399 BOOL message_error;
2400
2401 switch(save_errno)
2402 {
2403 case 0:
2404 case ERRNO_MAIL4XX:
2405 case ERRNO_DATA4XX:
2406 message_error = TRUE;
2407 break;
2408
2409 case ETIMEDOUT:
2410 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
2411 Ustrncmp(smtp_command,"end ",4) == 0;
2412 break;
2413
2414 case ERRNO_SMTPCLOSED:
2415 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
2416 break;
2417
2418 default:
2419 message_error = FALSE;
2420 break;
2421 }
2422
2423 /* Handle the cases that are treated as message errors. These are:
2424
2425 (a) negative response or timeout after MAIL
2426 (b) negative response after DATA
2427 (c) negative response or timeout or dropped connection after "."
2428
2429 It won't be a negative response or timeout after RCPT, as that is dealt
2430 with separately above. The action in all cases is to set an appropriate
2431 error code for all the addresses, but to leave yield set to OK because the
2432 host itself has not failed. Of course, it might in practice have failed
2433 when we've had a timeout, but if so, we'll discover that at the next
2434 delivery attempt. For a temporary error, set the message_defer flag, and
2435 write to the logs for information if this is not the last host. The error
2436 for the last host will be logged as part of the address's log line. */
2437
2438 if (message_error)
2439 {
2440 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
2441 set_errno(addrlist, save_errno, message, (code == '5')? FAIL : DEFER,
2442 pass_message, host);
2443
2444 /* If there's an errno, the message contains just the identity of
2445 the host. */
2446
2447 if (code != '5') /* Anything other than 5 is treated as temporary */
2448 {
2449 if (save_errno > 0)
2450 message = US string_sprintf("%s: %s", message, strerror(save_errno));
2451 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
2452 msglog_line(host, message);
2453 *message_defer = TRUE;
2454 }
2455 }
2456
2457 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
2458 ".", or some other transportation error. We defer all addresses and yield
2459 DEFER, except for the case of failed add_headers expansion, or a transport
2460 filter failure, when the yield should be ERROR, to stop it trying other
2461 hosts. */
2462
2463 else
2464 {
2465 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
2466 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
2467 set_errno(addrlist, save_errno, message, DEFER, pass_message, host);
2468 }
2469 }
2470 }
2471
2472
2473 /* If all has gone well, send_quit will be set TRUE, implying we can end the
2474 SMTP session tidily. However, if there were too many addresses to send in one
2475 message (indicated by first_addr being non-NULL) we want to carry on with the
2476 rest of them. Also, it is desirable to send more than one message down the SMTP
2477 connection if there are several waiting, provided we haven't already sent so
2478 many as to hit the configured limit. The function transport_check_waiting looks
2479 for a waiting message and returns its id. Then transport_pass_socket tries to
2480 set up a continued delivery by passing the socket on to another process. The
2481 variable send_rset is FALSE if a message has just been successfully transfered.
2482
2483 If we are already sending down a continued channel, there may be further
2484 addresses not yet delivered that are aimed at the same host, but which have not
2485 been passed in this run of the transport. In this case, continue_more will be
2486 true, and all we should do is send RSET if necessary, and return, leaving the
2487 channel open.
2488
2489 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
2490 do not want to continue with other messages down the same channel, because that
2491 can lead to looping between two or more messages, all with the same,
2492 temporarily failing address(es). [The retry information isn't updated yet, so
2493 new processes keep on trying.] We probably also don't want to try more of this
2494 message's addresses either.
2495
2496 If we have started a TLS session, we have to end it before passing the
2497 connection to a new process. However, not all servers can handle this (Exim
2498 can), so we do not pass such a connection on if the host matches
2499 hosts_nopass_tls. */
2500
2501 DEBUG(D_transport)
2502 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
2503 "yield=%d first_address is %sNULL\n", ok, send_quit, send_rset,
2504 continue_more, yield, (first_addr == NULL)? "":"not ");
2505
2506 if (completed_address && ok && send_quit)
2507 {
2508 BOOL more;
2509 if ( first_addr != NULL
2510 || continue_more
2511 || ( ( tls_out.active < 0
2512 || verify_check_given_host(&ob->hosts_nopass_tls, host) != OK
2513 )
2514 &&
2515 transport_check_waiting(tblock->name, host->name,
2516 tblock->connection_max_messages, new_message_id, &more)
2517 ) )
2518 {
2519 uschar *msg;
2520 BOOL pass_message;
2521
2522 if (send_rset)
2523 {
2524 if (! (ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
2525 {
2526 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
2527 host->address, strerror(save_errno));
2528 send_quit = FALSE;
2529 }
2530 else if (! (ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2531 ob->command_timeout)))
2532 {
2533 int code;
2534 send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
2535 &pass_message);
2536 if (!send_quit)
2537 {
2538 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
2539 host->name, host->address, msg);
2540 }
2541 }
2542 }
2543
2544 /* Either RSET was not needed, or it succeeded */
2545
2546 if (ok)
2547 {
2548 if (first_addr != NULL) /* More addresses still to be sent */
2549 { /* in this run of the transport */
2550 continue_sequence++; /* Causes * in logging */
2551 goto SEND_MESSAGE;
2552 }
2553 if (continue_more) return yield; /* More addresses for another run */
2554
2555 /* Pass the socket to a new Exim process. Before doing so, we must shut
2556 down TLS. Not all MTAs allow for the continuation of the SMTP session
2557 when TLS is shut down. We test for this by sending a new EHLO. If we
2558 don't get a good response, we don't attempt to pass the socket on. */
2559
2560 #ifdef SUPPORT_TLS
2561 if (tls_out.active >= 0)
2562 {
2563 tls_close(FALSE, TRUE);
2564 if (smtps)
2565 ok = FALSE;
2566 else
2567 ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
2568 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2569 ob->command_timeout);
2570 }
2571 #endif
2572
2573 /* If the socket is successfully passed, we musn't send QUIT (or
2574 indeed anything!) from here. */
2575
2576 if (ok && transport_pass_socket(tblock->name, host->name, host->address,
2577 new_message_id, inblock.sock))
2578 {
2579 send_quit = FALSE;
2580 }
2581 }
2582
2583 /* If RSET failed and there are addresses left, they get deferred. */
2584
2585 else set_errno(first_addr, errno, msg, DEFER, FALSE, host);
2586 }
2587 }
2588
2589 /* End off tidily with QUIT unless the connection has died or the socket has
2590 been passed to another process. There has been discussion on the net about what
2591 to do after sending QUIT. The wording of the RFC suggests that it is necessary
2592 to wait for a response, but on the other hand, there isn't anything one can do
2593 with an error response, other than log it. Exim used to do that. However,
2594 further discussion suggested that it is positively advantageous not to wait for
2595 the response, but to close the session immediately. This is supposed to move
2596 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
2597 load from the server. (Hosts that are both servers and clients may not see much
2598 difference, of course.) Further discussion indicated that this was safe to do
2599 on Unix systems which have decent implementations of TCP/IP that leave the
2600 connection around for a while (TIME_WAIT) after the application has gone away.
2601 This enables the response sent by the server to be properly ACKed rather than
2602 timed out, as can happen on broken TCP/IP implementations on other OS.
2603
2604 This change is being made on 31-Jul-98. After over a year of trouble-free
2605 operation, the old commented-out code was removed on 17-Sep-99. */
2606
2607 SEND_QUIT:
2608 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2609
2610 END_OFF:
2611
2612 #ifdef SUPPORT_TLS
2613 tls_close(FALSE, TRUE);
2614 #endif
2615
2616 /* Close the socket, and return the appropriate value, first setting
2617 works because the NULL setting is passed back to the calling process, and
2618 remote_max_parallel is forced to 1 when delivering over an existing connection,
2619
2620 If all went well and continue_more is set, we shouldn't actually get here if
2621 there are further addresses, as the return above will be taken. However,
2622 writing RSET might have failed, or there may be other addresses whose hosts are
2623 specified in the transports, and therefore not visible at top level, in which
2624 case continue_more won't get set. */
2625
2626 (void)close(inblock.sock);
2627
2628 #ifdef EXPERIMENTAL_EVENT
2629 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
2630 #endif
2631
2632 continue_transport = NULL;
2633 continue_hostname = NULL;
2634 return yield;
2635 }
2636
2637
2638
2639
2640 /*************************************************
2641 * Closedown entry point *
2642 *************************************************/
2643
2644 /* This function is called when exim is passed an open smtp channel
2645 from another incarnation, but the message which it has been asked
2646 to deliver no longer exists. The channel is on stdin.
2647
2648 We might do fancy things like looking for another message to send down
2649 the channel, but if the one we sought has gone, it has probably been
2650 delivered by some other process that itself will seek further messages,
2651 so just close down our connection.
2652
2653 Argument: pointer to the transport instance block
2654 Returns: nothing
2655 */
2656
2657 void
2658 smtp_transport_closedown(transport_instance *tblock)
2659 {
2660 smtp_transport_options_block *ob =
2661 (smtp_transport_options_block *)(tblock->options_block);
2662 smtp_inblock inblock;
2663 smtp_outblock outblock;
2664 uschar buffer[256];
2665 uschar inbuffer[4096];
2666 uschar outbuffer[16];
2667
2668 inblock.sock = fileno(stdin);
2669 inblock.buffer = inbuffer;
2670 inblock.buffersize = sizeof(inbuffer);
2671 inblock.ptr = inbuffer;
2672 inblock.ptrend = inbuffer;
2673
2674 outblock.sock = inblock.sock;
2675 outblock.buffersize = sizeof(outbuffer);
2676 outblock.buffer = outbuffer;
2677 outblock.ptr = outbuffer;
2678 outblock.cmd_count = 0;
2679 outblock.authenticating = FALSE;
2680
2681 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2682 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2683 ob->command_timeout);
2684 (void)close(inblock.sock);
2685 }
2686
2687
2688
2689 /*************************************************
2690 * Prepare addresses for delivery *
2691 *************************************************/
2692
2693 /* This function is called to flush out error settings from previous delivery
2694 attempts to other hosts. It also records whether we got here via an MX record
2695 or not in the more_errno field of the address. We are interested only in
2696 addresses that are still marked DEFER - others may have got delivered to a
2697 previously considered IP address. Set their status to PENDING_DEFER to indicate
2698 which ones are relevant this time.
2699
2700 Arguments:
2701 addrlist the list of addresses
2702 host the host we are delivering to
2703
2704 Returns: the first address for this delivery
2705 */
2706
2707 static address_item *
2708 prepare_addresses(address_item *addrlist, host_item *host)
2709 {
2710 address_item *first_addr = NULL;
2711 address_item *addr;
2712 for (addr = addrlist; addr != NULL; addr = addr->next)
2713 {
2714 if (addr->transport_return != DEFER) continue;
2715 if (first_addr == NULL) first_addr = addr;
2716 addr->transport_return = PENDING_DEFER;
2717 addr->basic_errno = 0;
2718 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
2719 addr->message = NULL;
2720 #ifdef SUPPORT_TLS
2721 addr->cipher = NULL;
2722 addr->ourcert = NULL;
2723 addr->peercert = NULL;
2724 addr->peerdn = NULL;
2725 addr->ocsp = OCSP_NOT_REQ;
2726 #endif
2727 }
2728 return first_addr;
2729 }
2730
2731
2732
2733 /*************************************************
2734 * Main entry point *
2735 *************************************************/
2736
2737 /* See local README for interface details. As this is a remote transport, it is
2738 given a chain of addresses to be delivered in one connection, if possible. It
2739 always returns TRUE, indicating that each address has its own independent
2740 status set, except if there is a setting up problem, in which case it returns
2741 FALSE. */
2742
2743 BOOL
2744 smtp_transport_entry(
2745 transport_instance *tblock, /* data for this instantiation */
2746 address_item *addrlist) /* addresses we are working on */
2747 {
2748 int cutoff_retry;
2749 int port;
2750 int hosts_defer = 0;
2751 int hosts_fail = 0;
2752 int hosts_looked_up = 0;
2753 int hosts_retry = 0;
2754 int hosts_serial = 0;
2755 int hosts_total = 0;
2756 int total_hosts_tried = 0;
2757 address_item *addr;
2758 BOOL expired = TRUE;
2759 BOOL continuing = continue_hostname != NULL;
2760 uschar *expanded_hosts = NULL;
2761 uschar *pistring;
2762 uschar *tid = string_sprintf("%s transport", tblock->name);
2763 smtp_transport_options_block *ob =
2764 (smtp_transport_options_block *)(tblock->options_block);
2765 host_item *hostlist = addrlist->host_list;
2766 host_item *host = NULL;
2767
2768 DEBUG(D_transport)
2769 {
2770 debug_printf("%s transport entered\n", tblock->name);
2771 for (addr = addrlist; addr != NULL; addr = addr->next)
2772 debug_printf(" %s\n", addr->address);
2773 if (continuing) debug_printf("already connected to %s [%s]\n",
2774 continue_hostname, continue_host_address);
2775 }
2776
2777 /* Set the flag requesting that these hosts be added to the waiting
2778 database if the delivery fails temporarily or if we are running with
2779 queue_smtp or a 2-stage queue run. This gets unset for certain
2780 kinds of error, typically those that are specific to the message. */
2781
2782 update_waiting = TRUE;
2783
2784 /* If a host list is not defined for the addresses - they must all have the
2785 same one in order to be passed to a single transport - or if the transport has
2786 a host list with hosts_override set, use the host list supplied with the
2787 transport. It is an error for this not to exist. */
2788
2789 if (hostlist == NULL || (ob->hosts_override && ob->hosts != NULL))
2790 {
2791 if (ob->hosts == NULL)
2792 {
2793 addrlist->message = string_sprintf("%s transport called with no hosts set",
2794 tblock->name);
2795 addrlist->transport_return = PANIC;
2796 return FALSE; /* Only top address has status */
2797 }
2798
2799 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
2800 ob->hosts);
2801
2802 /* If the transport's host list contains no '$' characters, and we are not
2803 randomizing, it is fixed and therefore a chain of hosts can be built once
2804 and for all, and remembered for subsequent use by other calls to this
2805 transport. If, on the other hand, the host list does contain '$', or we are
2806 randomizing its order, we have to rebuild it each time. In the fixed case,
2807 as the hosts string will never be used again, it doesn't matter that we
2808 replace all the : characters with zeros. */
2809
2810 if (ob->hostlist == NULL)
2811 {
2812 uschar *s = ob->hosts;
2813
2814 if (Ustrchr(s, '$') != NULL)
2815 {
2816 if (!(expanded_hosts = expand_string(s)))
2817 {
2818 addrlist->message = string_sprintf("failed to expand list of hosts "
2819 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
2820 addrlist->transport_return = search_find_defer? DEFER : PANIC;
2821 return FALSE; /* Only top address has status */
2822 }
2823 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
2824 "\"%s\"\n", s, expanded_hosts);
2825 s = expanded_hosts;
2826 }
2827 else
2828 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
2829
2830 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
2831
2832 /* Check that the expansion yielded something useful. */
2833 if (hostlist == NULL)
2834 {
2835 addrlist->message =
2836 string_sprintf("%s transport has empty hosts setting", tblock->name);
2837 addrlist->transport_return = PANIC;
2838 return FALSE; /* Only top address has status */
2839 }
2840
2841 /* If there was no expansion of hosts, save the host list for
2842 next time. */
2843
2844 if (!expanded_hosts) ob->hostlist = hostlist;
2845 }
2846
2847 /* This is not the first time this transport has been run in this delivery;
2848 the host list was built previously. */
2849
2850 else hostlist = ob->hostlist;
2851 }
2852
2853 /* The host list was supplied with the address. If hosts_randomize is set, we
2854 must sort it into a random order if it did not come from MX records and has not
2855 already been randomized (but don't bother if continuing down an existing
2856 connection). */
2857
2858 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continuing)
2859 {
2860 host_item *newlist = NULL;
2861 while (hostlist != NULL)
2862 {
2863 host_item *h = hostlist;
2864 hostlist = hostlist->next;
2865
2866 h->sort_key = random_number(100);
2867
2868 if (newlist == NULL)
2869 {
2870 h->next = NULL;
2871 newlist = h;
2872 }
2873 else if (h->sort_key < newlist->sort_key)
2874 {
2875 h->next = newlist;
2876 newlist = h;
2877 }
2878 else
2879 {
2880 host_item *hh = newlist;
2881 while (hh->next != NULL)
2882 {
2883 if (h->sort_key < hh->next->sort_key) break;
2884 hh = hh->next;
2885 }
2886 h->next = hh->next;
2887 hh->next = h;
2888 }
2889 }
2890
2891 hostlist = addrlist->host_list = newlist;
2892 }
2893
2894
2895 /* Sort out the default port. */
2896
2897 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
2898
2899
2900 /* For each host-plus-IP-address on the list:
2901
2902 . If this is a continued delivery and the host isn't the one with the
2903 current connection, skip.
2904
2905 . If the status is unusable (i.e. previously failed or retry checked), skip.
2906
2907 . If no IP address set, get the address, either by turning the name into
2908 an address, calling gethostbyname if gethostbyname is on, or by calling
2909 the DNS. The DNS may yield multiple addresses, in which case insert the
2910 extra ones into the list.
2911
2912 . Get the retry data if not previously obtained for this address and set the
2913 field which remembers the state of this address. Skip if the retry time is
2914 not reached. If not, remember whether retry data was found. The retry string
2915 contains both the name and the IP address.
2916
2917 . Scan the list of addresses and mark those whose status is DEFER as
2918 PENDING_DEFER. These are the only ones that will be processed in this cycle
2919 of the hosts loop.
2920
2921 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
2922 Some addresses may be successfully delivered, others may fail, and yet
2923 others may get temporary errors and so get marked DEFER.
2924
2925 . The return from the delivery attempt is OK if a connection was made and a
2926 valid SMTP dialogue was completed. Otherwise it is DEFER.
2927
2928 . If OK, add a "remove" retry item for this host/IPaddress, if any.
2929
2930 . If fail to connect, or other defer state, add a retry item.
2931
2932 . If there are any addresses whose status is still DEFER, carry on to the
2933 next host/IPaddress, unless we have tried the number of hosts given
2934 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
2935 there is some fancy logic for hosts_max_try that means its limit can be
2936 overstepped in some circumstances.
2937
2938 If we get to the end of the list, all hosts have deferred at least one address,
2939 or not reached their retry times. If delay_after_cutoff is unset, it requests a
2940 delivery attempt to those hosts whose last try was before the arrival time of
2941 the current message. To cope with this, we have to go round the loop a second
2942 time. After that, set the status and error data for any addresses that haven't
2943 had it set already. */
2944
2945 for (cutoff_retry = 0; expired &&
2946 cutoff_retry < ((ob->delay_after_cutoff)? 1 : 2);
2947 cutoff_retry++)
2948 {
2949 host_item *nexthost = NULL;
2950 int unexpired_hosts_tried = 0;
2951
2952 for (host = hostlist;
2953 host != NULL &&
2954 unexpired_hosts_tried < ob->hosts_max_try &&
2955 total_hosts_tried < ob->hosts_max_try_hardlimit;
2956 host = nexthost)
2957 {
2958 int rc;
2959 int host_af;
2960 uschar *rs;
2961 BOOL serialized = FALSE;
2962 BOOL host_is_expired = FALSE;
2963 BOOL message_defer = FALSE;
2964 BOOL ifchanges = FALSE;
2965 BOOL some_deferred = FALSE;
2966 address_item *first_addr = NULL;
2967 uschar *interface = NULL;
2968 uschar *retry_host_key = NULL;
2969 uschar *retry_message_key = NULL;
2970 uschar *serialize_key = NULL;
2971
2972 /* Default next host is next host. :-) But this can vary if the
2973 hosts_max_try limit is hit (see below). It may also be reset if a host
2974 address is looked up here (in case the host was multihomed). */
2975
2976 nexthost = host->next;
2977
2978 /* If the address hasn't yet been obtained from the host name, look it up
2979 now, unless the host is already marked as unusable. If it is marked as
2980 unusable, it means that the router was unable to find its IP address (in
2981 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
2982 the lookup failed last time. We don't get this far if *all* MX records
2983 point to non-existent hosts; that is treated as a hard error.
2984
2985 We can just skip this host entirely. When the hosts came from the router,
2986 the address will timeout based on the other host(s); when the address is
2987 looked up below, there is an explicit retry record added.
2988
2989 Note that we mustn't skip unusable hosts if the address is not unset; they
2990 may be needed as expired hosts on the 2nd time round the cutoff loop. */
2991
2992 if (host->address == NULL)
2993 {
2994 int new_port, flags;
2995 host_item *hh;
2996 uschar *canonical_name;
2997
2998 if (host->status >= hstatus_unusable)
2999 {
3000 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
3001 host->name);
3002 continue;
3003 }
3004
3005 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
3006
3007 /* The host name is permitted to have an attached port. Find it, and
3008 strip it from the name. Just remember it for now. */
3009
3010 new_port = host_item_get_port(host);
3011
3012 /* Count hosts looked up */
3013
3014 hosts_looked_up++;
3015
3016 /* Find by name if so configured, or if it's an IP address. We don't
3017 just copy the IP address, because we need the test-for-local to happen. */
3018
3019 flags = HOST_FIND_BY_A;
3020 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
3021 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
3022
3023 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
3024 rc = host_find_byname(host, NULL, flags, &canonical_name, TRUE);
3025 else
3026 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
3027 ob->dnssec_request_domains, ob->dnssec_require_domains,
3028 &canonical_name, NULL);
3029
3030 /* Update the host (and any additional blocks, resulting from
3031 multihoming) with a host-specific port, if any. */
3032
3033 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
3034
3035 /* Failure to find the host at this time (usually DNS temporary failure)
3036 is really a kind of routing failure rather than a transport failure.
3037 Therefore we add a retry item of the routing kind, not to stop us trying
3038 to look this name up here again, but to ensure the address gets timed
3039 out if the failures go on long enough. A complete failure at this point
3040 commonly points to a configuration error, but the best action is still
3041 to carry on for the next host. */
3042
3043 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
3044 {
3045 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
3046 expired = FALSE;
3047 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
3048 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
3049 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
3050 host->status = hstatus_unusable;
3051
3052 for (addr = addrlist; addr != NULL; addr = addr->next)
3053 {
3054 if (addr->transport_return != DEFER) continue;
3055 addr->basic_errno = ERRNO_UNKNOWNHOST;
3056 addr->message =
3057 string_sprintf("failed to lookup IP address for %s", host->name);
3058 }
3059 continue;
3060 }
3061
3062 /* If the host is actually the local host, we may have a problem, or
3063 there may be some cunning configuration going on. In the problem case,
3064 log things and give up. The default transport status is already DEFER. */
3065
3066 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
3067 {
3068 for (addr = addrlist; addr != NULL; addr = addr->next)
3069 {
3070 addr->basic_errno = 0;
3071 addr->message = string_sprintf("%s transport found host %s to be "
3072 "local", tblock->name, host->name);
3073 }
3074 goto END_TRANSPORT;
3075 }
3076 } /* End of block for IP address lookup */
3077
3078 /* If this is a continued delivery, we are interested only in the host
3079 which matches the name of the existing open channel. The check is put
3080 here after the local host lookup, in case the name gets expanded as a
3081 result of the lookup. Set expired FALSE, to save the outer loop executing
3082 twice. */
3083
3084 if (continuing && (Ustrcmp(continue_hostname, host->name) != 0 ||
3085 Ustrcmp(continue_host_address, host->address) != 0))
3086 {
3087 expired = FALSE;
3088 continue; /* With next host */
3089 }
3090
3091 /* Reset the default next host in case a multihomed host whose addresses
3092 are not looked up till just above added to the host list. */
3093
3094 nexthost = host->next;
3095
3096 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
3097 domain is in queue_smtp_domains, we don't actually want to attempt any
3098 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
3099 there is a lookup defer in queue_smtp_domains, proceed as if the domain
3100 were not in it. We don't want to hold up all SMTP deliveries! Except when
3101 doing a two-stage queue run, don't do this if forcing. */
3102
3103 if ((!deliver_force || queue_2stage) && (queue_smtp ||
3104 match_isinlist(addrlist->domain, &queue_smtp_domains, 0,
3105 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
3106 {
3107 expired = FALSE;
3108 for (addr = addrlist; addr != NULL; addr = addr->next)
3109 {
3110 if (addr->transport_return != DEFER) continue;
3111 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
3112 }
3113 continue; /* With next host */
3114 }
3115
3116 /* Count hosts being considered - purely for an intelligent comment
3117 if none are usable. */
3118
3119 hosts_total++;
3120
3121 /* Set $host and $host address now in case they are needed for the
3122 interface expansion or the serialize_hosts check; they remain set if an
3123 actual delivery happens. */
3124
3125 deliver_host = host->name;
3126 deliver_host_address = host->address;
3127 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
3128 : host->dnssec == DS_NO ? US"no"
3129 : US"";
3130
3131 /* Set up a string for adding to the retry key if the port number is not
3132 the standard SMTP port. A host may have its own port setting that overrides
3133 the default. */
3134
3135 pistring = string_sprintf(":%d", (host->port == PORT_NONE)?
3136 port : host->port);
3137 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
3138
3139 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
3140 string changes upon expansion, we must add it to the key that is used for
3141 retries, because connections to the same host from a different interface
3142 should be treated separately. */
3143
3144 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET : AF_INET6;
3145 if (!smtp_get_interface(ob->interface, host_af, addrlist, &ifchanges,
3146 &interface, tid))
3147 return FALSE;
3148 if (ifchanges) pistring = string_sprintf("%s/%s", pistring, interface);
3149
3150 /* The first time round the outer loop, check the status of the host by
3151 inspecting the retry data. The second time round, we are interested only
3152 in expired hosts that haven't been tried since this message arrived. */
3153
3154 if (cutoff_retry == 0)
3155 {
3156 BOOL incl_ip;
3157 /* Ensure the status of the address is set by checking retry data if
3158 necessary. There may be host-specific retry data (applicable to all
3159 messages) and also data for retries of a specific message at this host.
3160 If either of these retry records are actually read, the keys used are
3161 returned to save recomputing them later. */
3162
3163 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3164 US"retry_include_ip_address", ob->retry_include_ip_address,
3165 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3166 continue; /* with next host */
3167
3168 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
3169 incl_ip, &retry_host_key, &retry_message_key);
3170
3171 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
3172 (host->address == NULL)? US"" : host->address, pistring,
3173 (host->status == hstatus_usable)? "usable" :
3174 (host->status == hstatus_unusable)? "unusable" :
3175 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
3176
3177 /* Skip this address if not usable at this time, noting if it wasn't
3178 actually expired, both locally and in the address. */
3179
3180 switch (host->status)
3181 {
3182 case hstatus_unusable:
3183 expired = FALSE;
3184 setflag(addrlist, af_retry_skipped);
3185 /* Fall through */
3186
3187 case hstatus_unusable_expired:
3188 switch (host->why)
3189 {
3190 case hwhy_retry: hosts_retry++; break;
3191 case hwhy_failed: hosts_fail++; break;
3192 case hwhy_deferred: hosts_defer++; break;
3193 }
3194
3195 /* If there was a retry message key, implying that previously there
3196 was a message-specific defer, we don't want to update the list of
3197 messages waiting for these hosts. */
3198
3199 if (retry_message_key != NULL) update_waiting = FALSE;
3200 continue; /* With the next host or IP address */
3201 }
3202 }
3203
3204 /* Second time round the loop: if the address is set but expired, and
3205 the message is newer than the last try, let it through. */
3206
3207 else
3208 {
3209 if (host->address == NULL ||
3210 host->status != hstatus_unusable_expired ||
3211 host->last_try > received_time)
3212 continue;
3213 DEBUG(D_transport)
3214 debug_printf("trying expired host %s [%s]%s\n",
3215 host->name, host->address, pistring);
3216 host_is_expired = TRUE;
3217 }
3218
3219 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
3220 it remains TRUE only if all hosts are expired and none are actually tried.
3221 */
3222
3223 expired = FALSE;
3224
3225 /* If this host is listed as one to which access must be serialized,
3226 see if another Exim process has a connection to it, and if so, skip
3227 this host. If not, update the database to record our connection to it
3228 and remember this for later deletion. Do not do any of this if we are
3229 sending the message down a pre-existing connection. */
3230
3231 if (!continuing &&
3232 verify_check_given_host(&ob->serialize_hosts, host) == OK)
3233 {
3234 serialize_key = string_sprintf("host-serialize-%s", host->name);
3235 if (!enq_start(serialize_key))
3236 {
3237 DEBUG(D_transport)
3238 debug_printf("skipping host %s because another Exim process "
3239 "is connected to it\n", host->name);
3240 hosts_serial++;
3241 continue;
3242 }
3243 serialized = TRUE;
3244 }
3245
3246 /* OK, we have an IP address that is not waiting for its retry time to
3247 arrive (it might be expired) OR (second time round the loop) we have an
3248 expired host that hasn't been tried since the message arrived. Have a go
3249 at delivering the message to it. First prepare the addresses by flushing
3250 out the result of previous attempts, and finding the first address that
3251 is still to be delivered. */
3252
3253 first_addr = prepare_addresses(addrlist, host);
3254
3255 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
3256 message_id, host->name, host->address, addrlist->address,
3257 (addrlist->next == NULL)? "" : ", ...");
3258
3259 set_process_info("delivering %s to %s [%s] (%s%s)",
3260 message_id, host->name, host->address, addrlist->address,
3261 (addrlist->next == NULL)? "" : ", ...");
3262
3263 /* This is not for real; don't do the delivery. If there are
3264 any remaining hosts, list them. */
3265
3266 if (dont_deliver)
3267 {
3268 host_item *host2;
3269 set_errno(addrlist, 0, NULL, OK, FALSE, NULL);
3270 for (addr = addrlist; addr != NULL; addr = addr->next)
3271 {
3272 addr->host_used = host;
3273 addr->special_action = '*';
3274 addr->message = US"delivery bypassed by -N option";
3275 }
3276 DEBUG(D_transport)
3277 {
3278 debug_printf("*** delivery by %s transport bypassed by -N option\n"
3279 "*** host and remaining hosts:\n", tblock->name);
3280 for (host2 = host; host2 != NULL; host2 = host2->next)
3281 debug_printf(" %s [%s]\n", host2->name,
3282 (host2->address == NULL)? US"unset" : host2->address);
3283 }
3284 rc = OK;
3285 }
3286
3287 /* This is for real. If the host is expired, we don't count it for
3288 hosts_max_retry. This ensures that all hosts must expire before an address
3289 is timed out, unless hosts_max_try_hardlimit (which protects against
3290 lunatic DNS configurations) is reached.
3291
3292 If the host is not expired and we are about to hit the hosts_max_retry
3293 limit, check to see if there is a subsequent hosts with a different MX
3294 value. If so, make that the next host, and don't count this one. This is a
3295 heuristic to make sure that different MXs do get tried. With a normal kind
3296 of retry rule, they would get tried anyway when the earlier hosts were
3297 delayed, but if the domain has a "retry every time" type of rule - as is
3298 often used for the the very large ISPs, that won't happen. */
3299
3300 else
3301 {
3302 host_item * thost;
3303 /* Make a copy of the host if it is local to this invocation
3304 of the transport. */
3305
3306 if (expanded_hosts)
3307 {
3308 thost = store_get(sizeof(host_item));
3309 *thost = *host;
3310 thost->name = string_copy(host->name);
3311 thost->address = string_copy(host->address);
3312 }
3313 else
3314 thost = host;
3315
3316 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
3317 {
3318 host_item *h;
3319 DEBUG(D_transport)
3320 debug_printf("hosts_max_try limit reached with this host\n");
3321 for (h = host; h != NULL; h = h->next)
3322 if (h->mx != host->mx) break;
3323 if (h != NULL)
3324 {
3325 nexthost = h;
3326 unexpired_hosts_tried--;
3327 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
3328 "and will be tried\n");
3329 }
3330 }
3331
3332 /* Attempt the delivery. */
3333
3334 total_hosts_tried++;
3335 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
3336 &message_defer, FALSE);
3337
3338 /* Yield is one of:
3339 OK => connection made, each address contains its result;
3340 message_defer is set for message-specific defers (when all
3341 recipients are marked defer)
3342 DEFER => there was a non-message-specific delivery problem;
3343 ERROR => there was a problem setting up the arguments for a filter,
3344 or there was a problem with expanding added headers
3345 */
3346
3347 /* If the result is not OK, there was a non-message-specific problem.
3348 If the result is DEFER, we need to write to the logs saying what happened
3349 for this particular host, except in the case of authentication and TLS
3350 failures, where the log has already been written. If all hosts defer a
3351 general message is written at the end. */
3352
3353 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL &&
3354 first_addr->basic_errno != ERRNO_TLSFAILURE)
3355 write_logs(first_addr, host);
3356
3357 #ifdef EXPERIMENTAL_EVENT
3358 if (rc == DEFER)
3359 deferred_event_raise(first_addr, host);
3360 #endif
3361
3362 /* If STARTTLS was accepted, but there was a failure in setting up the
3363 TLS session (usually a certificate screwup), and the host is not in
3364 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
3365 TLS forcibly turned off. We have to start from scratch with a new SMTP
3366 connection. That's why the retry is done from here, not from within
3367 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
3368 session, so the in-clear transmission after those errors, if permitted,
3369 happens inside smtp_deliver().] */
3370
3371 #ifdef SUPPORT_TLS
3372 if ( rc == DEFER
3373 && first_addr->basic_errno == ERRNO_TLSFAILURE
3374 && ob->tls_tempfail_tryclear
3375 && verify_check_given_host(&ob->hosts_require_tls, host) != OK
3376 )
3377 {
3378 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
3379 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
3380 first_addr = prepare_addresses(addrlist, host);
3381 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
3382 &message_defer, TRUE);
3383 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
3384 write_logs(first_addr, host);
3385 # ifdef EXPERIMENTAL_EVENT
3386 if (rc == DEFER)
3387 deferred_event_raise(first_addr, host);
3388 # endif
3389 }
3390 #endif /*SUPPORT_TLS*/
3391 }
3392
3393 /* Delivery attempt finished */
3394
3395 rs = (rc == OK)? US"OK" : (rc == DEFER)? US"DEFER" : (rc == ERROR)?
3396 US"ERROR" : US"?";
3397
3398 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
3399 message_id, host->name, host->address, addrlist->address,
3400 (addrlist->next == NULL)? "" : " (& others)", rs);
3401
3402 /* Release serialization if set up */
3403
3404 if (serialized) enq_end(serialize_key);
3405
3406 /* If the result is DEFER, or if a host retry record is known to exist, we
3407 need to add an item to the retry chain for updating the retry database
3408 at the end of delivery. We only need to add the item to the top address,
3409 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
3410 for any other delivery attempts using the same address. (It is copied into
3411 the unusable tree at the outer level, so even if different address blocks
3412 contain the same address, it still won't get tried again.) */
3413
3414 if (rc == DEFER || retry_host_key != NULL)
3415 {
3416 int delete_flag = (rc != DEFER)? rf_delete : 0;
3417 if (retry_host_key == NULL)
3418 {
3419 BOOL incl_ip;
3420 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3421 US"retry_include_ip_address", ob->retry_include_ip_address,
3422 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3423 incl_ip = TRUE; /* error; use most-specific retry record */
3424
3425 retry_host_key = incl_ip ?
3426 string_sprintf("T:%S:%s%s", host->name, host->address, pistring) :
3427 string_sprintf("T:%S%s", host->name, pistring);
3428 }
3429
3430 /* If a delivery of another message over an existing SMTP connection
3431 yields DEFER, we do NOT set up retry data for the host. This covers the
3432 case when there are delays in routing the addresses in the second message
3433 that are so long that the server times out. This is alleviated by not
3434 routing addresses that previously had routing defers when handling an
3435 existing connection, but even so, this case may occur (e.g. if a
3436 previously happily routed address starts giving routing defers). If the
3437 host is genuinely down, another non-continued message delivery will
3438 notice it soon enough. */
3439
3440 if (delete_flag != 0 || !continuing)
3441 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
3442
3443 /* We may have tried an expired host, if its retry time has come; ensure
3444 the status reflects the expiry for the benefit of any other addresses. */
3445
3446 if (rc == DEFER)
3447 {
3448 host->status = (host_is_expired)?
3449 hstatus_unusable_expired : hstatus_unusable;
3450 host->why = hwhy_deferred;
3451 }
3452 }
3453
3454 /* If message_defer is set (host was OK, but every recipient got deferred
3455 because of some message-specific problem), or if that had happened
3456 previously so that a message retry key exists, add an appropriate item
3457 to the retry chain. Note that if there was a message defer but now there is
3458 a host defer, the message defer record gets deleted. That seems perfectly
3459 reasonable. Also, stop the message from being remembered as waiting
3460 for specific hosts. */
3461
3462 if (message_defer || retry_message_key != NULL)
3463 {
3464 int delete_flag = message_defer? 0 : rf_delete;
3465 if (retry_message_key == NULL)
3466 {
3467 BOOL incl_ip;
3468 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3469 US"retry_include_ip_address", ob->retry_include_ip_address,
3470 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3471 incl_ip = TRUE; /* error; use most-specific retry record */
3472
3473 retry_message_key = incl_ip ?
3474 string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
3475 message_id) :
3476 string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
3477 }
3478 retry_add_item(addrlist, retry_message_key,
3479 rf_message | rf_host | delete_flag);
3480 update_waiting = FALSE;
3481 }
3482
3483 /* Any return other than DEFER (that is, OK or ERROR) means that the
3484 addresses have got their final statuses filled in for this host. In the OK
3485 case, see if any of them are deferred. */
3486
3487 if (rc == OK)
3488 {
3489 for (addr = addrlist; addr != NULL; addr = addr->next)
3490 {
3491 if (addr->transport_return == DEFER)
3492 {
3493 some_deferred = TRUE;
3494 break;
3495 }
3496 }
3497 }
3498
3499 /* If no addresses deferred or the result was ERROR, return. We do this for
3500 ERROR because a failing filter set-up or add_headers expansion is likely to
3501 fail for any host we try. */
3502
3503 if (rc == ERROR || (rc == OK && !some_deferred))
3504 {
3505 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3506 return TRUE; /* Each address has its status */
3507 }
3508
3509 /* If the result was DEFER or some individual addresses deferred, let
3510 the loop run to try other hosts with the deferred addresses, except for the
3511 case when we were trying to deliver down an existing channel and failed.
3512 Don't try any other hosts in this case. */
3513
3514 if (continuing) break;
3515
3516 /* If the whole delivery, or some individual addresses, were deferred and
3517 there are more hosts that could be tried, do not count this host towards
3518 the hosts_max_try limit if the age of the message is greater than the
3519 maximum retry time for this host. This means we may try try all hosts,
3520 ignoring the limit, when messages have been around for some time. This is
3521 important because if we don't try all hosts, the address will never time
3522 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
3523
3524 if ((rc == DEFER || some_deferred) && nexthost != NULL)
3525 {
3526 BOOL timedout;
3527 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
3528
3529 if (retry != NULL && retry->rules != NULL)
3530 {
3531 retry_rule *last_rule;
3532 for (last_rule = retry->rules;
3533 last_rule->next != NULL;
3534 last_rule = last_rule->next);
3535 timedout = time(NULL) - received_time > last_rule->timeout;
3536 }
3537 else timedout = TRUE; /* No rule => timed out */
3538
3539 if (timedout)
3540 {
3541 unexpired_hosts_tried--;
3542 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
3543 "hosts_max_try (message older than host's retry time)\n");
3544 }
3545 }
3546 } /* End of loop for trying multiple hosts. */
3547
3548 /* This is the end of the loop that repeats iff expired is TRUE and
3549 ob->delay_after_cutoff is FALSE. The second time round we will
3550 try those hosts that haven't been tried since the message arrived. */
3551
3552 DEBUG(D_transport)
3553 {
3554 debug_printf("all IP addresses skipped or deferred at least one address\n");
3555 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
3556 debug_printf("retrying IP addresses not tried since message arrived\n");
3557 }
3558 }
3559
3560
3561 /* Get here if all IP addresses are skipped or defer at least one address. In
3562 MUA wrapper mode, this will happen only for connection or other non-message-
3563 specific failures. Force the delivery status for all addresses to FAIL. */
3564
3565 if (mua_wrapper)
3566 {
3567 for (addr = addrlist; addr != NULL; addr = addr->next)
3568 addr->transport_return = FAIL;
3569 goto END_TRANSPORT;
3570 }
3571
3572 /* In the normal, non-wrapper case, add a standard message to each deferred
3573 address if there hasn't been an error, that is, if it hasn't actually been
3574 tried this time. The variable "expired" will be FALSE if any deliveries were
3575 actually tried, or if there was at least one host that was not expired. That
3576 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
3577 a delivery has been tried, an error code will be set, and the failing of the
3578 message is handled by the retry code later.
3579
3580 If queue_smtp is set, or this transport was called to send a subsequent message
3581 down an existing TCP/IP connection, and something caused the host not to be
3582 found, we end up here, but can detect these cases and handle them specially. */
3583
3584 for (addr = addrlist; addr != NULL; addr = addr->next)
3585 {
3586 /* If host is not NULL, it means that we stopped processing the host list
3587 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
3588 means we need to behave as if some hosts were skipped because their retry
3589 time had not come. Specifically, this prevents the address from timing out.
3590 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
3591 hosts were tried. */
3592
3593 if (host != NULL)
3594 {
3595 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
3596 {
3597 DEBUG(D_transport)
3598 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
3599 "hosts were tried\n");
3600 }
3601 else
3602 {
3603 DEBUG(D_transport)
3604 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
3605 setflag(addr, af_retry_skipped);
3606 }
3607 }
3608
3609 if (queue_smtp) /* no deliveries attempted */
3610 {
3611 addr->transport_return = DEFER;
3612 addr->basic_errno = 0;
3613 addr->message = US"SMTP delivery explicitly queued";
3614 }
3615
3616 else if (addr->transport_return == DEFER &&
3617 (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0) &&
3618 addr->message == NULL)
3619 {
3620 addr->basic_errno = ERRNO_HRETRY;
3621 if (continue_hostname != NULL)
3622 {
3623 addr->message = US"no host found for existing SMTP connection";
3624 }
3625 else if (expired)
3626 {
3627 setflag(addr, af_pass_message); /* This is not a security risk */
3628 addr->message = (ob->delay_after_cutoff)?
3629 US"retry time not reached for any host after a long failure period" :
3630 US"all hosts have been failing for a long time and were last tried "
3631 "after this message arrived";
3632
3633 /* If we are already using fallback hosts, or there are no fallback hosts
3634 defined, convert the result to FAIL to cause a bounce. */
3635
3636 if (addr->host_list == addr->fallback_hosts ||
3637 addr->fallback_hosts == NULL)
3638 addr->transport_return = FAIL;
3639 }
3640 else
3641 {
3642 if (hosts_retry == hosts_total)
3643 addr->message = US"retry time not reached for any host";
3644 else if (hosts_fail == hosts_total)
3645 addr->message = US"all host address lookups failed permanently";
3646 else if (hosts_defer == hosts_total)
3647 addr->message = US"all host address lookups failed temporarily";
3648 else if (hosts_serial == hosts_total)
3649 addr->message = US"connection limit reached for all hosts";
3650 else if (hosts_fail+hosts_defer == hosts_total)
3651 addr->message = US"all host address lookups failed";
3652 else addr->message = US"some host address lookups failed and retry time "
3653 "not reached for other hosts or connection limit reached";
3654 }
3655 }
3656 }
3657
3658 /* Update the database which keeps information about which messages are waiting
3659 for which hosts to become available. For some message-specific errors, the
3660 update_waiting flag is turned off because we don't want follow-on deliveries in
3661 those cases. If this transport instance is explicitly limited to one message
3662 per connection then follow-on deliveries are not possible and there's no need
3663 to create/update the per-transport wait-<transport_name> database. */
3664
3665 if (update_waiting && tblock->connection_max_messages != 1)
3666 transport_update_waiting(hostlist, tblock->name);
3667
3668 END_TRANSPORT:
3669
3670 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3671
3672 return TRUE; /* Each address has its status */
3673 }
3674
3675 /* vi: aw ai sw=2
3676 */
3677 /* End of transport/smtp.c */
Unnamed repository; edit this file 'description' to name the repository.