projects / exim.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
Fix cert-try-verify when denied by event action
[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 { "address_retry_include_sender", opt_bool,
23 (void *)offsetof(smtp_transport_options_block, address_retry_include_sender) },
24 { "allow_localhost", opt_bool,
25 (void *)offsetof(smtp_transport_options_block, allow_localhost) },
26 { "authenticated_sender", opt_stringptr,
27 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
28 { "authenticated_sender_force", opt_bool,
29 (void *)offsetof(smtp_transport_options_block, authenticated_sender_force) },
30 { "command_timeout", opt_time,
31 (void *)offsetof(smtp_transport_options_block, command_timeout) },
32 { "connect_timeout", opt_time,
33 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
34 { "connection_max_messages", opt_int | opt_public,
35 (void *)offsetof(transport_instance, connection_max_messages) },
36 { "data_timeout", opt_time,
37 (void *)offsetof(smtp_transport_options_block, data_timeout) },
38 { "delay_after_cutoff", opt_bool,
39 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
40 #ifndef DISABLE_DKIM
41 { "dkim_canon", opt_stringptr,
42 (void *)offsetof(smtp_transport_options_block, dkim_canon) },
43 { "dkim_domain", opt_stringptr,
44 (void *)offsetof(smtp_transport_options_block, dkim_domain) },
45 { "dkim_private_key", opt_stringptr,
46 (void *)offsetof(smtp_transport_options_block, dkim_private_key) },
47 { "dkim_selector", opt_stringptr,
48 (void *)offsetof(smtp_transport_options_block, dkim_selector) },
49 { "dkim_sign_headers", opt_stringptr,
50 (void *)offsetof(smtp_transport_options_block, dkim_sign_headers) },
51 { "dkim_strict", opt_stringptr,
52 (void *)offsetof(smtp_transport_options_block, dkim_strict) },
53 #endif
54 { "dns_qualify_single", opt_bool,
55 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
56 { "dns_search_parents", opt_bool,
57 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
58 { "dnssec_request_domains", opt_stringptr,
59 (void *)offsetof(smtp_transport_options_block, dnssec_request_domains) },
60 { "dnssec_require_domains", opt_stringptr,
61 (void *)offsetof(smtp_transport_options_block, dnssec_require_domains) },
62 { "dscp", opt_stringptr,
63 (void *)offsetof(smtp_transport_options_block, dscp) },
64 { "fallback_hosts", opt_stringptr,
65 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
66 { "final_timeout", opt_time,
67 (void *)offsetof(smtp_transport_options_block, final_timeout) },
68 { "gethostbyname", opt_bool,
69 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
70 #ifdef SUPPORT_TLS
71 /* These are no longer honoured, as of Exim 4.80; for now, we silently
72 ignore; 4.83 will warn, and a later-still release will remove
73 these options, so that using them becomes an error. */
74 { "gnutls_require_kx", opt_stringptr,
75 (void *)offsetof(smtp_transport_options_block, gnutls_require_kx) },
76 { "gnutls_require_mac", opt_stringptr,
77 (void *)offsetof(smtp_transport_options_block, gnutls_require_mac) },
78 { "gnutls_require_protocols", opt_stringptr,
79 (void *)offsetof(smtp_transport_options_block, gnutls_require_proto) },
80 #endif
81 { "helo_data", opt_stringptr,
82 (void *)offsetof(smtp_transport_options_block, helo_data) },
83 { "hosts", opt_stringptr,
84 (void *)offsetof(smtp_transport_options_block, hosts) },
85 { "hosts_avoid_esmtp", opt_stringptr,
86 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
87 { "hosts_avoid_pipelining", opt_stringptr,
88 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
89 #ifdef SUPPORT_TLS
90 { "hosts_avoid_tls", opt_stringptr,
91 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
92 #endif
93 { "hosts_max_try", opt_int,
94 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
95 { "hosts_max_try_hardlimit", opt_int,
96 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
97 #ifdef SUPPORT_TLS
98 { "hosts_nopass_tls", opt_stringptr,
99 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
100 #endif
101 { "hosts_override", opt_bool,
102 (void *)offsetof(smtp_transport_options_block, hosts_override) },
103 { "hosts_randomize", opt_bool,
104 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
105 #if defined(SUPPORT_TLS) && !defined(DISABLE_OCSP)
106 { "hosts_request_ocsp", opt_stringptr,
107 (void *)offsetof(smtp_transport_options_block, hosts_request_ocsp) },
108 #endif
109 { "hosts_require_auth", opt_stringptr,
110 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
111 #ifdef SUPPORT_TLS
112 # ifdef EXPERIMENTAL_DANE
113 { "hosts_require_dane", opt_stringptr,
114 (void *)offsetof(smtp_transport_options_block, hosts_require_dane) },
115 # endif
116 # ifndef DISABLE_OCSP
117 { "hosts_require_ocsp", opt_stringptr,
118 (void *)offsetof(smtp_transport_options_block, hosts_require_ocsp) },
119 # endif
120 { "hosts_require_tls", opt_stringptr,
121 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
122 #endif
123 { "hosts_try_auth", opt_stringptr,
124 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
125 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
126 { "hosts_try_dane", opt_stringptr,
127 (void *)offsetof(smtp_transport_options_block, hosts_try_dane) },
128 #endif
129 #ifndef DISABLE_PRDR
130 { "hosts_try_prdr", opt_stringptr,
131 (void *)offsetof(smtp_transport_options_block, hosts_try_prdr) },
132 #endif
133 #ifdef SUPPORT_TLS
134 { "hosts_verify_avoid_tls", opt_stringptr,
135 (void *)offsetof(smtp_transport_options_block, hosts_verify_avoid_tls) },
136 #endif
137 { "interface", opt_stringptr,
138 (void *)offsetof(smtp_transport_options_block, interface) },
139 { "keepalive", opt_bool,
140 (void *)offsetof(smtp_transport_options_block, keepalive) },
141 { "lmtp_ignore_quota", opt_bool,
142 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
143 { "max_rcpt", opt_int | opt_public,
144 (void *)offsetof(transport_instance, max_addresses) },
145 { "multi_domain", opt_bool | opt_public,
146 (void *)offsetof(transport_instance, multi_domain) },
147 { "port", opt_stringptr,
148 (void *)offsetof(smtp_transport_options_block, port) },
149 { "protocol", opt_stringptr,
150 (void *)offsetof(smtp_transport_options_block, protocol) },
151 { "retry_include_ip_address", opt_bool,
152 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
153 { "serialize_hosts", opt_stringptr,
154 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
155 { "size_addition", opt_int,
156 (void *)offsetof(smtp_transport_options_block, size_addition) }
157 #ifdef SUPPORT_TLS
158 ,{ "tls_certificate", opt_stringptr,
159 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
160 { "tls_crl", opt_stringptr,
161 (void *)offsetof(smtp_transport_options_block, tls_crl) },
162 { "tls_dh_min_bits", opt_int,
163 (void *)offsetof(smtp_transport_options_block, tls_dh_min_bits) },
164 { "tls_privatekey", opt_stringptr,
165 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
166 { "tls_require_ciphers", opt_stringptr,
167 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
168 { "tls_sni", opt_stringptr,
169 (void *)offsetof(smtp_transport_options_block, tls_sni) },
170 { "tls_tempfail_tryclear", opt_bool,
171 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
172 { "tls_try_verify_hosts", opt_stringptr,
173 (void *)offsetof(smtp_transport_options_block, tls_try_verify_hosts) },
174 #ifdef EXPERIMENTAL_CERTNAMES
175 { "tls_verify_cert_hostnames", opt_stringptr,
176 (void *)offsetof(smtp_transport_options_block,tls_verify_cert_hostnames)},
177 #endif
178 { "tls_verify_certificates", opt_stringptr,
179 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) },
180 { "tls_verify_hosts", opt_stringptr,
181 (void *)offsetof(smtp_transport_options_block, tls_verify_hosts) }
182 #endif
183 };
184
185 /* Size of the options list. An extern variable has to be used so that its
186 address can appear in the tables drtables.c. */
187
188 int smtp_transport_options_count =
189 sizeof(smtp_transport_options)/sizeof(optionlist);
190
191 /* Default private options block for the smtp transport. */
192
193 smtp_transport_options_block smtp_transport_option_defaults = {
194 NULL, /* hosts */
195 NULL, /* fallback_hosts */
196 NULL, /* hostlist */
197 NULL, /* fallback_hostlist */
198 NULL, /* authenticated_sender */
199 US"$primary_hostname", /* helo_data */
200 NULL, /* interface */
201 NULL, /* port */
202 US"smtp", /* protocol */
203 NULL, /* DSCP */
204 NULL, /* serialize_hosts */
205 NULL, /* hosts_try_auth */
206 NULL, /* hosts_require_auth */
207 #ifdef EXPERIMENTAL_DANE
208 NULL, /* hosts_try_dane */
209 NULL, /* hosts_require_dane */
210 #endif
211 #ifndef DISABLE_PRDR
212 NULL, /* hosts_try_prdr */
213 #endif
214 #ifndef DISABLE_OCSP
215 US"*", /* hosts_request_ocsp (except under DANE; tls_client_start()) */
216 NULL, /* hosts_require_ocsp */
217 #endif
218 NULL, /* hosts_require_tls */
219 NULL, /* hosts_avoid_tls */
220 US"*", /* hosts_verify_avoid_tls */
221 NULL, /* hosts_avoid_pipelining */
222 NULL, /* hosts_avoid_esmtp */
223 NULL, /* hosts_nopass_tls */
224 5*60, /* command_timeout */
225 5*60, /* connect_timeout; shorter system default overrides */
226 5*60, /* data timeout */
227 10*60, /* final timeout */
228 1024, /* size_addition */
229 5, /* hosts_max_try */
230 50, /* hosts_max_try_hardlimit */
231 TRUE, /* address_retry_include_sender */
232 FALSE, /* allow_localhost */
233 FALSE, /* authenticated_sender_force */
234 FALSE, /* gethostbyname */
235 TRUE, /* dns_qualify_single */
236 FALSE, /* dns_search_parents */
237 NULL, /* dnssec_request_domains */
238 NULL, /* dnssec_require_domains */
239 TRUE, /* delay_after_cutoff */
240 FALSE, /* hosts_override */
241 FALSE, /* hosts_randomize */
242 TRUE, /* keepalive */
243 FALSE, /* lmtp_ignore_quota */
244 TRUE /* retry_include_ip_address */
245 #ifdef SUPPORT_TLS
246 ,NULL, /* tls_certificate */
247 NULL, /* tls_crl */
248 NULL, /* tls_privatekey */
249 NULL, /* tls_require_ciphers */
250 NULL, /* gnutls_require_kx */
251 NULL, /* gnutls_require_mac */
252 NULL, /* gnutls_require_proto */
253 NULL, /* tls_sni */
254 NULL, /* tls_verify_certificates */
255 EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
256 /* tls_dh_min_bits */
257 TRUE, /* tls_tempfail_tryclear */
258 NULL, /* tls_verify_hosts */
259 NULL /* tls_try_verify_hosts */
260 # ifdef EXPERIMENTAL_CERTNAMES
261 ,NULL /* tls_verify_cert_hostnames */
262 # endif
263 #endif
264 #ifndef DISABLE_DKIM
265 ,NULL, /* dkim_canon */
266 NULL, /* dkim_domain */
267 NULL, /* dkim_private_key */
268 NULL, /* dkim_selector */
269 NULL, /* dkim_sign_headers */
270 NULL /* dkim_strict */
271 #endif
272 };
273
274 #ifdef EXPERIMENTAL_DSN
275 /* some DSN flags for use later */
276
277 static int rf_list[] = {rf_notify_never, rf_notify_success,
278 rf_notify_failure, rf_notify_delay };
279
280 static uschar *rf_names[] = { "NEVER", "SUCCESS", "FAILURE", "DELAY" };
281 #endif
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_this_host(&(ob->hosts_require_auth), NULL,
974 host->name, host->address, NULL);
975
976 if (is_esmtp && !regex_AUTH) regex_AUTH =
977 regex_must_compile(US"\\n250[\\s\\-]AUTH\\s+([\\-\\w\\s]+)(?:\\n|$)",
978 FALSE, TRUE);
979
980 if (is_esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
981 {
982 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
983 expand_nmax = -1; /* reset */
984
985 /* Must not do this check until after we have saved the result of the
986 regex match above. */
987
988 if (require_auth == OK ||
989 verify_check_this_host(&(ob->hosts_try_auth), NULL, host->name,
990 host->address, NULL) == OK)
991 {
992 auth_instance *au;
993 fail_reason = US"no common mechanisms were found";
994
995 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
996
997 /* Scan the configured authenticators looking for one which is configured
998 for use as a client, which is not suppressed by client_condition, and
999 whose name matches an authentication mechanism supported by the server.
1000 If one is found, attempt to authenticate by calling its client function.
1001 */
1002
1003 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1004 {
1005 uschar *p = names;
1006 if (!au->client ||
1007 (au->client_condition != NULL &&
1008 !expand_check_condition(au->client_condition, au->name,
1009 US"client authenticator")))
1010 {
1011 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1012 au->name,
1013 (au->client)? "client_condition is false" :
1014 "not configured as a client");
1015 continue;
1016 }
1017
1018 /* Loop to scan supported server mechanisms */
1019
1020 while (*p != 0)
1021 {
1022 int rc;
1023 int len = Ustrlen(au->public_name);
1024 while (isspace(*p)) p++;
1025
1026 if (strncmpic(au->public_name, p, len) != 0 ||
1027 (p[len] != 0 && !isspace(p[len])))
1028 {
1029 while (*p != 0 && !isspace(*p)) p++;
1030 continue;
1031 }
1032
1033 /* Found data for a listed mechanism. Call its client entry. Set
1034 a flag in the outblock so that data is overwritten after sending so
1035 that reflections don't show it. */
1036
1037 fail_reason = US"authentication attempt(s) failed";
1038 obp->authenticating = TRUE;
1039 rc = (au->info->clientcode)(au, ibp, obp,
1040 ob->command_timeout, buffer, bufsize);
1041 obp->authenticating = FALSE;
1042 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1043 au->name, rc);
1044
1045 /* A temporary authentication failure must hold up delivery to
1046 this host. After a permanent authentication failure, we carry on
1047 to try other authentication methods. If all fail hard, try to
1048 deliver the message unauthenticated unless require_auth was set. */
1049
1050 switch(rc)
1051 {
1052 case OK:
1053 smtp_authenticated = TRUE; /* stops the outer loop */
1054 client_authenticator = au->name;
1055 if (au->set_client_id != NULL)
1056 client_authenticated_id = expand_string(au->set_client_id);
1057 break;
1058
1059 /* Failure after writing a command */
1060
1061 case FAIL_SEND:
1062 return FAIL_SEND;
1063
1064 /* Failure after reading a response */
1065
1066 case FAIL:
1067 if (errno != 0 || buffer[0] != '5') return FAIL;
1068 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1069 au->name, host->name, host->address, buffer);
1070 break;
1071
1072 /* Failure by some other means. In effect, the authenticator
1073 decided it wasn't prepared to handle this case. Typically this
1074 is the result of "fail" in an expansion string. Do we need to
1075 log anything here? Feb 2006: a message is now put in the buffer
1076 if logging is required. */
1077
1078 case CANCELLED:
1079 if (*buffer != 0)
1080 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1081 "authentication H=%s [%s] %s", au->name, host->name,
1082 host->address, buffer);
1083 break;
1084
1085 /* Internal problem, message in buffer. */
1086
1087 case ERROR:
1088 set_errno(addrlist, 0, string_copy(buffer), DEFER, FALSE, NULL);
1089 return ERROR;
1090 }
1091
1092 break; /* If not authenticated, try next authenticator */
1093 } /* Loop for scanning supported server mechanisms */
1094 } /* Loop for further authenticators */
1095 }
1096 }
1097
1098 /* If we haven't authenticated, but are required to, give up. */
1099
1100 if (require_auth == OK && !smtp_authenticated)
1101 {
1102 set_errno(addrlist, ERRNO_AUTHFAIL,
1103 string_sprintf("authentication required but %s", fail_reason), DEFER,
1104 FALSE, NULL);
1105 return DEFER;
1106 }
1107
1108 return OK;
1109 }
1110
1111
1112 /* Construct AUTH appendix string for MAIL TO */
1113 /*
1114 Arguments
1115 buffer to build string
1116 addrlist chain of potential addresses to deliver
1117 ob transport options
1118
1119 Globals smtp_authenticated
1120 client_authenticated_sender
1121 Return True on error, otherwise buffer has (possibly empty) terminated string
1122 */
1123
1124 BOOL
1125 smtp_mail_auth_str(uschar *buffer, unsigned bufsize, address_item *addrlist,
1126 smtp_transport_options_block *ob)
1127 {
1128 uschar *local_authenticated_sender = authenticated_sender;
1129
1130 #ifdef notdef
1131 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n", authenticated_sender, ob->authenticated_sender, smtp_authenticated?"Y":"N");
1132 #endif
1133
1134 if (ob->authenticated_sender != NULL)
1135 {
1136 uschar *new = expand_string(ob->authenticated_sender);
1137 if (new == NULL)
1138 {
1139 if (!expand_string_forcedfail)
1140 {
1141 uschar *message = string_sprintf("failed to expand "
1142 "authenticated_sender: %s", expand_string_message);
1143 set_errno(addrlist, 0, message, DEFER, FALSE, NULL);
1144 return TRUE;
1145 }
1146 }
1147 else if (new[0] != 0) local_authenticated_sender = new;
1148 }
1149
1150 /* Add the authenticated sender address if present */
1151
1152 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1153 local_authenticated_sender != NULL)
1154 {
1155 string_format(buffer, bufsize, " AUTH=%s",
1156 auth_xtextencode(local_authenticated_sender,
1157 Ustrlen(local_authenticated_sender)));
1158 client_authenticated_sender = string_copy(local_authenticated_sender);
1159 }
1160 else
1161 *buffer= 0;
1162
1163 return FALSE;
1164 }
1165
1166
1167
1168 #ifdef EXPERIMENTAL_DANE
1169 int
1170 tlsa_lookup(host_item * host, dns_answer * dnsa,
1171 BOOL dane_required, BOOL * dane)
1172 {
1173 /* move this out to host.c given the similarity to dns_lookup() ? */
1174 uschar buffer[300];
1175 uschar * fullname = buffer;
1176
1177 /* TLSA lookup string */
1178 (void)sprintf(CS buffer, "_%d._tcp.%.256s", host->port, host->name);
1179
1180 switch (dns_lookup(dnsa, buffer, T_TLSA, &fullname))
1181 {
1182 case DNS_AGAIN:
1183 return DEFER; /* just defer this TLS'd conn */
1184
1185 default:
1186 case DNS_FAIL:
1187 if (dane_required)
1188 {
1189 log_write(0, LOG_MAIN, "DANE error: TLSA lookup failed");
1190 return FAIL;
1191 }
1192 break;
1193
1194 case DNS_SUCCEED:
1195 if (!dns_is_secure(dnsa))
1196 {
1197 log_write(0, LOG_MAIN, "DANE error: TLSA lookup not DNSSEC");
1198 return DEFER;
1199 }
1200 *dane = TRUE;
1201 break;
1202 }
1203 return OK;
1204 }
1205 #endif
1206
1207
1208 /*************************************************
1209 * Deliver address list to given host *
1210 *************************************************/
1211
1212 /* If continue_hostname is not null, we get here only when continuing to
1213 deliver down an existing channel. The channel was passed as the standard
1214 input. TLS is never active on a passed channel; the previous process always
1215 closes it down before passing the connection on.
1216
1217 Otherwise, we have to make a connection to the remote host, and do the
1218 initial protocol exchange.
1219
1220 When running as an MUA wrapper, if the sender or any recipient is rejected,
1221 temporarily or permanently, we force failure for all recipients.
1222
1223 Arguments:
1224 addrlist chain of potential addresses to deliver; only those whose
1225 transport_return field is set to PENDING_DEFER are currently
1226 being processed; others should be skipped - they have either
1227 been delivered to an earlier host or IP address, or been
1228 failed by one of them.
1229 host host to deliver to
1230 host_af AF_INET or AF_INET6
1231 port default TCP/IP port to use, in host byte order
1232 interface interface to bind to, or NULL
1233 tblock transport instance block
1234 copy_host TRUE if host set in addr->host_used must be copied, because
1235 it is specific to this call of the transport
1236 message_defer set TRUE if yield is OK, but all addresses were deferred
1237 because of a non-recipient, non-host failure, that is, a
1238 4xx response to MAIL FROM, DATA, or ".". This is a defer
1239 that is specific to the message.
1240 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1241 a second attempt after TLS initialization fails
1242
1243 Returns: OK - the connection was made and the delivery attempted;
1244 the result for each address is in its data block.
1245 DEFER - the connection could not be made, or something failed
1246 while setting up the SMTP session, or there was a
1247 non-message-specific error, such as a timeout.
1248 ERROR - a filter command is specified for this transport,
1249 and there was a problem setting it up; OR helo_data
1250 or add_headers or authenticated_sender is specified
1251 for this transport, and the string failed to expand
1252 */
1253
1254 static int
1255 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
1256 uschar *interface, transport_instance *tblock, BOOL copy_host,
1257 BOOL *message_defer, BOOL suppress_tls)
1258 {
1259 address_item *addr;
1260 address_item *sync_addr;
1261 address_item *first_addr = addrlist;
1262 int yield = OK;
1263 int address_count;
1264 int save_errno;
1265 int rc;
1266 time_t start_delivery_time = time(NULL);
1267 smtp_transport_options_block *ob =
1268 (smtp_transport_options_block *)(tblock->options_block);
1269 BOOL lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
1270 BOOL smtps = strcmpic(ob->protocol, US"smtps") == 0;
1271 BOOL ok = FALSE;
1272 BOOL send_rset = TRUE;
1273 BOOL send_quit = TRUE;
1274 BOOL setting_up = TRUE;
1275 BOOL completed_address = FALSE;
1276 BOOL esmtp = TRUE;
1277 BOOL pending_MAIL;
1278 BOOL pass_message = FALSE;
1279 #ifndef DISABLE_PRDR
1280 BOOL prdr_offered = FALSE;
1281 BOOL prdr_active;
1282 #endif
1283 #ifdef EXPERIMENTAL_DSN
1284 BOOL dsn_all_lasthop = TRUE;
1285 #endif
1286 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1287 BOOL dane = FALSE;
1288 dns_answer tlsa_dnsa;
1289 #endif
1290 smtp_inblock inblock;
1291 smtp_outblock outblock;
1292 int max_rcpt = tblock->max_addresses;
1293 uschar *igquotstr = US"";
1294 uschar *helo_data = NULL;
1295 uschar *message = NULL;
1296 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
1297 uschar *p;
1298 uschar buffer[4096];
1299 uschar inbuffer[4096];
1300 uschar outbuffer[4096];
1301
1302 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
1303
1304 *message_defer = FALSE;
1305 smtp_command = US"initial connection";
1306 if (max_rcpt == 0) max_rcpt = 999999;
1307
1308 /* Set up the buffer for reading SMTP response packets. */
1309
1310 inblock.buffer = inbuffer;
1311 inblock.buffersize = sizeof(inbuffer);
1312 inblock.ptr = inbuffer;
1313 inblock.ptrend = inbuffer;
1314
1315 /* Set up the buffer for holding SMTP commands while pipelining */
1316
1317 outblock.buffer = outbuffer;
1318 outblock.buffersize = sizeof(outbuffer);
1319 outblock.ptr = outbuffer;
1320 outblock.cmd_count = 0;
1321 outblock.authenticating = FALSE;
1322
1323 /* Reset the parameters of a TLS session. */
1324
1325 tls_out.bits = 0;
1326 tls_out.cipher = NULL; /* the one we may use for this transport */
1327 tls_out.ourcert = NULL;
1328 tls_out.peercert = NULL;
1329 tls_out.peerdn = NULL;
1330 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1331 tls_out.sni = NULL;
1332 #endif
1333 tls_out.ocsp = OCSP_NOT_REQ;
1334
1335 /* Flip the legacy TLS-related variables over to the outbound set in case
1336 they're used in the context of the transport. Don't bother resetting
1337 afterward as we're in a subprocess. */
1338
1339 tls_modify_variables(&tls_out);
1340
1341 #ifndef SUPPORT_TLS
1342 if (smtps)
1343 {
1344 set_errno(addrlist, 0, US"TLS support not available", DEFER, FALSE, NULL);
1345 return ERROR;
1346 }
1347 #endif
1348
1349 /* Make a connection to the host if this isn't a continued delivery, and handle
1350 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
1351 specially so they can be identified for retries. */
1352
1353 if (continue_hostname == NULL)
1354 {
1355 /* This puts port into host->port */
1356 inblock.sock = outblock.sock =
1357 smtp_connect(host, host_af, port, interface, ob->connect_timeout,
1358 ob->keepalive, ob->dscp
1359 #ifdef EXPERIMENTAL_EVENT
1360 , tblock->event_action
1361 #endif
1362 );
1363
1364 if (inblock.sock < 0)
1365 {
1366 set_errno(addrlist, (errno == ETIMEDOUT)? ERRNO_CONNECTTIMEOUT : errno,
1367 NULL, DEFER, FALSE, NULL);
1368 return DEFER;
1369 }
1370
1371 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1372 {
1373 BOOL dane_required;
1374
1375 tls_out.dane_verified = FALSE;
1376 tls_out.tlsa_usage = 0;
1377
1378 dane_required = verify_check_this_host(&ob->hosts_require_dane, NULL,
1379 host->name, host->address, NULL) == OK;
1380
1381 if (host->dnssec == DS_YES)
1382 {
1383 if( dane_required
1384 || verify_check_this_host(&ob->hosts_try_dane, NULL,
1385 host->name, host->address, NULL) == OK
1386 )
1387 if ((rc = tlsa_lookup(host, &tlsa_dnsa, dane_required, &dane)) != OK)
1388 return rc;
1389 }
1390 else if (dane_required)
1391 {
1392 log_write(0, LOG_MAIN, "DANE error: %s lookup not DNSSEC", host->name);
1393 return FAIL;
1394 }
1395
1396 if (dane)
1397 ob->tls_tempfail_tryclear = FALSE;
1398 }
1399 #endif /*DANE*/
1400
1401 /* Expand the greeting message while waiting for the initial response. (Makes
1402 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1403 delayed till here so that $sending_interface and $sending_port are set. */
1404
1405 helo_data = expand_string(ob->helo_data);
1406
1407 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1408 is nevertheless a reasonably clean way of programming this kind of logic,
1409 where you want to escape on any error. */
1410
1411 if (!smtps)
1412 {
1413 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1414 ob->command_timeout)) goto RESPONSE_FAILED;
1415
1416 #ifdef EXPERIMENTAL_EVENT
1417 {
1418 uschar * s;
1419 lookup_dnssec_authenticated = host->dnssec==DS_YES ? US"yes"
1420 : host->dnssec==DS_NO ? US"no" : NULL;
1421 s = event_raise(tblock->event_action, US"smtp:connect", buffer);
1422 if (s)
1423 {
1424 set_errno(addrlist, 0,
1425 string_sprintf("deferred by smtp:connect event expansion: %s", s),
1426 DEFER, FALSE, NULL);
1427 yield = DEFER;
1428 goto SEND_QUIT;
1429 }
1430 }
1431 #endif
1432
1433 /* Now check if the helo_data expansion went well, and sign off cleanly if
1434 it didn't. */
1435
1436 if (helo_data == NULL)
1437 {
1438 uschar *message = string_sprintf("failed to expand helo_data: %s",
1439 expand_string_message);
1440 set_errno(addrlist, 0, message, DEFER, FALSE, NULL);
1441 yield = DEFER;
1442 goto SEND_QUIT;
1443 }
1444 }
1445
1446 /** Debugging without sending a message
1447 addrlist->transport_return = DEFER;
1448 goto SEND_QUIT;
1449 **/
1450
1451 /* Errors that occur after this point follow an SMTP command, which is
1452 left in big_buffer by smtp_write_command() for use in error messages. */
1453
1454 smtp_command = big_buffer;
1455
1456 /* Tell the remote who we are...
1457
1458 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1459 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1460 greeting is of this form. The assumption was that the far end supports it
1461 properly... but experience shows that there are some that give 5xx responses,
1462 even though the banner includes "ESMTP" (there's a bloody-minded one that
1463 says "ESMTP not spoken here"). Cope with that case.
1464
1465 September 2000: Time has passed, and it seems reasonable now to always send
1466 EHLO at the start. It is also convenient to make the change while installing
1467 the TLS stuff.
1468
1469 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1470 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1471 would be no way to send out the mails, so there is now a host list
1472 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1473 PIPELINING problem as well. Maybe it can also be useful to cure other
1474 problems with broken servers.
1475
1476 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1477 Then somebody tried it with a Microsoft mailer... It seems that all other
1478 mailers use upper case for some reason (the RFC is quite clear about case
1479 independence) so, for peace of mind, I gave in. */
1480
1481 esmtp = verify_check_this_host(&(ob->hosts_avoid_esmtp), NULL,
1482 host->name, host->address, NULL) != OK;
1483
1484 /* Alas; be careful, since this goto is not an error-out, so conceivably
1485 we might set data between here and the target which we assume to exist
1486 and be usable. I can see this coming back to bite us. */
1487 #ifdef SUPPORT_TLS
1488 if (smtps)
1489 {
1490 tls_offered = TRUE;
1491 suppress_tls = FALSE;
1492 ob->tls_tempfail_tryclear = FALSE;
1493 smtp_command = US"SSL-on-connect";
1494 goto TLS_NEGOTIATE;
1495 }
1496 #endif
1497
1498 if (esmtp)
1499 {
1500 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1501 lmtp? "LHLO" : "EHLO", helo_data) < 0)
1502 goto SEND_FAILED;
1503 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1504 ob->command_timeout))
1505 {
1506 if (errno != 0 || buffer[0] == 0 || lmtp) goto RESPONSE_FAILED;
1507 esmtp = FALSE;
1508 }
1509 }
1510 else
1511 {
1512 DEBUG(D_transport)
1513 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1514 }
1515
1516 if (!esmtp)
1517 {
1518 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1519 goto SEND_FAILED;
1520 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1521 ob->command_timeout)) goto RESPONSE_FAILED;
1522 }
1523
1524 /* Set IGNOREQUOTA if the response to LHLO specifies support and the
1525 lmtp_ignore_quota option was set. */
1526
1527 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1528 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1529 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1530
1531 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1532
1533 #ifdef SUPPORT_TLS
1534 tls_offered = esmtp &&
1535 pcre_exec(regex_STARTTLS, NULL, CS buffer, Ustrlen(buffer), 0,
1536 PCRE_EOPT, NULL, 0) >= 0;
1537 #endif
1538
1539 #ifndef DISABLE_PRDR
1540 prdr_offered = esmtp &&
1541 (pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(buffer), 0,
1542 PCRE_EOPT, NULL, 0) >= 0) &&
1543 (verify_check_this_host(&(ob->hosts_try_prdr), NULL, host->name,
1544 host->address, NULL) == OK);
1545
1546 if (prdr_offered)
1547 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1548 #endif
1549 }
1550
1551 /* For continuing deliveries down the same channel, the socket is the standard
1552 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1553 below). Set up the pointer to where subsequent commands will be left, for
1554 error messages. Note that smtp_use_size and smtp_use_pipelining will have been
1555 set from the command line if they were set in the process that passed the
1556 connection on. */
1557
1558 else
1559 {
1560 inblock.sock = outblock.sock = fileno(stdin);
1561 smtp_command = big_buffer;
1562 host->port = port; /* Record the port that was used */
1563 }
1564
1565 /* If TLS is available on this connection, whether continued or not, attempt to
1566 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1567 send another EHLO - the server may give a different answer in secure mode. We
1568 use a separate buffer for reading the response to STARTTLS so that if it is
1569 negative, the original EHLO data is available for subsequent analysis, should
1570 the client not be required to use TLS. If the response is bad, copy the buffer
1571 for error analysis. */
1572
1573 #ifdef SUPPORT_TLS
1574 if (tls_offered && !suppress_tls &&
1575 verify_check_this_host(&(ob->hosts_avoid_tls), NULL, host->name,
1576 host->address, NULL) != OK)
1577 {
1578 uschar buffer2[4096];
1579 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1580 goto SEND_FAILED;
1581
1582 /* If there is an I/O error, transmission of this message is deferred. If
1583 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1584 false, we also defer. However, if there is a temporary rejection of STARTTLS
1585 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1586 STARTTLS, we carry on. This means we will try to send the message in clear,
1587 unless the host is in hosts_require_tls (tested below). */
1588
1589 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1590 ob->command_timeout))
1591 {
1592 if (errno != 0 || buffer2[0] == 0 ||
1593 (buffer2[0] == '4' && !ob->tls_tempfail_tryclear))
1594 {
1595 Ustrncpy(buffer, buffer2, sizeof(buffer));
1596 goto RESPONSE_FAILED;
1597 }
1598 }
1599
1600 /* STARTTLS accepted: try to negotiate a TLS session. */
1601
1602 else
1603 TLS_NEGOTIATE:
1604 {
1605 int rc = tls_client_start(inblock.sock, host, addrlist, tblock
1606 # ifdef EXPERIMENTAL_DANE
1607 , dane ? &tlsa_dnsa : NULL
1608 # endif
1609 );
1610
1611 /* TLS negotiation failed; give an error. From outside, this function may
1612 be called again to try in clear on a new connection, if the options permit
1613 it for this host. */
1614
1615 if (rc != OK)
1616 {
1617 save_errno = ERRNO_TLSFAILURE;
1618 message = US"failure while setting up TLS session";
1619 send_quit = FALSE;
1620 goto TLS_FAILED;
1621 }
1622
1623 /* TLS session is set up */
1624
1625 for (addr = addrlist; addr != NULL; addr = addr->next)
1626 if (addr->transport_return == PENDING_DEFER)
1627 {
1628 addr->cipher = tls_out.cipher;
1629 addr->ourcert = tls_out.ourcert;
1630 addr->peercert = tls_out.peercert;
1631 addr->peerdn = tls_out.peerdn;
1632 addr->ocsp = tls_out.ocsp;
1633 }
1634 }
1635 }
1636
1637 /* if smtps, we'll have smtp_command set to something else; always safe to
1638 reset it here. */
1639 smtp_command = big_buffer;
1640
1641 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1642 helo_data is null, we are dealing with a connection that was passed from
1643 another process, and so we won't have expanded helo_data above. We have to
1644 expand it here. $sending_ip_address and $sending_port are set up right at the
1645 start of the Exim process (in exim.c). */
1646
1647 if (tls_out.active >= 0)
1648 {
1649 char *greeting_cmd;
1650 if (helo_data == NULL)
1651 {
1652 helo_data = expand_string(ob->helo_data);
1653 if (helo_data == NULL)
1654 {
1655 uschar *message = string_sprintf("failed to expand helo_data: %s",
1656 expand_string_message);
1657 set_errno(addrlist, 0, message, DEFER, FALSE, NULL);
1658 yield = DEFER;
1659 goto SEND_QUIT;
1660 }
1661 }
1662
1663 /* For SMTPS we need to wait for the initial OK response. */
1664 if (smtps)
1665 {
1666 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1667 ob->command_timeout)) goto RESPONSE_FAILED;
1668 }
1669
1670 if (esmtp)
1671 greeting_cmd = "EHLO";
1672 else
1673 {
1674 greeting_cmd = "HELO";
1675 DEBUG(D_transport)
1676 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1677 }
1678
1679 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1680 lmtp? "LHLO" : greeting_cmd, helo_data) < 0)
1681 goto SEND_FAILED;
1682 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1683 ob->command_timeout))
1684 goto RESPONSE_FAILED;
1685 }
1686
1687 /* If the host is required to use a secure channel, ensure that we
1688 have one. */
1689
1690 else if (
1691 # ifdef EXPERIMENTAL_DANE
1692 dane ||
1693 # endif
1694 verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
1695 host->address, NULL) == OK
1696 )
1697 {
1698 save_errno = ERRNO_TLSREQUIRED;
1699 message = string_sprintf("a TLS session is required, but %s",
1700 tls_offered? "an attempt to start TLS failed" :
1701 "the server did not offer TLS support");
1702 goto TLS_FAILED;
1703 }
1704 #endif /*SUPPORT_TLS*/
1705
1706 /* If TLS is active, we have just started it up and re-done the EHLO command,
1707 so its response needs to be analyzed. If TLS is not active and this is a
1708 continued session down a previously-used socket, we haven't just done EHLO, so
1709 we skip this. */
1710
1711 if (continue_hostname == NULL
1712 #ifdef SUPPORT_TLS
1713 || tls_out.active >= 0
1714 #endif
1715 )
1716 {
1717 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
1718 lmtp_ignore_quota option was set. */
1719
1720 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1721 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1722 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1723
1724 /* If the response to EHLO specified support for the SIZE parameter, note
1725 this, provided size_addition is non-negative. */
1726
1727 smtp_use_size = esmtp && ob->size_addition >= 0 &&
1728 pcre_exec(regex_SIZE, NULL, CS buffer, Ustrlen(CS buffer), 0,
1729 PCRE_EOPT, NULL, 0) >= 0;
1730
1731 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
1732 the current host, esmtp will be false, so PIPELINING can never be used. If
1733 the current host matches hosts_avoid_pipelining, don't do it. */
1734
1735 smtp_use_pipelining = esmtp &&
1736 verify_check_this_host(&(ob->hosts_avoid_pipelining), NULL, host->name,
1737 host->address, NULL) != OK &&
1738 pcre_exec(regex_PIPELINING, NULL, CS buffer, Ustrlen(CS buffer), 0,
1739 PCRE_EOPT, NULL, 0) >= 0;
1740
1741 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
1742 smtp_use_pipelining? "" : "not ");
1743
1744 #ifndef DISABLE_PRDR
1745 prdr_offered = esmtp &&
1746 pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(CS buffer), 0,
1747 PCRE_EOPT, NULL, 0) >= 0 &&
1748 verify_check_this_host(&(ob->hosts_try_prdr), NULL, host->name,
1749 host->address, NULL) == OK;
1750
1751 if (prdr_offered)
1752 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1753 #endif
1754
1755 #ifdef EXPERIMENTAL_DSN
1756 /* Note if the server supports DSN */
1757 smtp_use_dsn = esmtp && pcre_exec(regex_DSN, NULL, CS buffer, (int)Ustrlen(CS buffer), 0,
1758 PCRE_EOPT, NULL, 0) >= 0;
1759 DEBUG(D_transport) debug_printf("use_dsn=%d\n", smtp_use_dsn);
1760 #endif
1761
1762 /* Note if the response to EHLO specifies support for the AUTH extension.
1763 If it has, check that this host is one we want to authenticate to, and do
1764 the business. The host name and address must be available when the
1765 authenticator's client driver is running. */
1766
1767 switch (yield = smtp_auth(buffer, sizeof(buffer), addrlist, host,
1768 ob, esmtp, &inblock, &outblock))
1769 {
1770 default: goto SEND_QUIT;
1771 case OK: break;
1772 case FAIL_SEND: goto SEND_FAILED;
1773 case FAIL: goto RESPONSE_FAILED;
1774 }
1775 }
1776
1777 /* The setting up of the SMTP call is now complete. Any subsequent errors are
1778 message-specific. */
1779
1780 setting_up = FALSE;
1781
1782 /* If there is a filter command specified for this transport, we can now
1783 set it up. This cannot be done until the identify of the host is known. */
1784
1785 if (tblock->filter_command != NULL)
1786 {
1787 BOOL rc;
1788 uschar buffer[64];
1789 sprintf(CS buffer, "%.50s transport", tblock->name);
1790 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
1791 TRUE, DEFER, addrlist, buffer, NULL);
1792 transport_filter_timeout = tblock->filter_timeout;
1793
1794 /* On failure, copy the error to all addresses, abandon the SMTP call, and
1795 yield ERROR. */
1796
1797 if (!rc)
1798 {
1799 set_errno(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
1800 FALSE, NULL);
1801 yield = ERROR;
1802 goto SEND_QUIT;
1803 }
1804 }
1805
1806
1807 /* For messages that have more than the maximum number of envelope recipients,
1808 we want to send several transactions down the same SMTP connection. (See
1809 comments in deliver.c as to how this reconciles, heuristically, with
1810 remote_max_parallel.) This optimization was added to Exim after the following
1811 code was already working. The simplest way to put it in without disturbing the
1812 code was to use a goto to jump back to this point when there is another
1813 transaction to handle. */
1814
1815 SEND_MESSAGE:
1816 sync_addr = first_addr;
1817 address_count = 0;
1818 ok = FALSE;
1819 send_rset = TRUE;
1820 completed_address = FALSE;
1821
1822
1823 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
1824 qualification, send it, adding something to the message size to allow for
1825 imprecision and things that get added en route. Exim keeps the number of lines
1826 in a message, so we can give an accurate value for the original message, but we
1827 need some additional to handle added headers. (Double "." characters don't get
1828 included in the count.) */
1829
1830 p = buffer;
1831 *p = 0;
1832
1833 if (smtp_use_size)
1834 {
1835 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
1836 while (*p) p++;
1837 }
1838
1839 #ifndef DISABLE_PRDR
1840 prdr_active = FALSE;
1841 if (prdr_offered)
1842 {
1843 for (addr = first_addr; addr; addr = addr->next)
1844 if (addr->transport_return == PENDING_DEFER)
1845 {
1846 for (addr = addr->next; addr; addr = addr->next)
1847 if (addr->transport_return == PENDING_DEFER)
1848 { /* at least two recipients to send */
1849 prdr_active = TRUE;
1850 sprintf(CS p, " PRDR"); p += 5;
1851 break;
1852 }
1853 break;
1854 }
1855 }
1856 #endif
1857
1858 #ifdef EXPERIMENTAL_DSN
1859 /* check if all addresses have lasthop flag */
1860 /* do not send RET and ENVID if true */
1861 dsn_all_lasthop = TRUE;
1862 for (addr = first_addr;
1863 address_count < max_rcpt && addr != NULL;
1864 addr = addr->next)
1865 if ((addr->dsn_flags & rf_dsnlasthop) != 1)
1866 dsn_all_lasthop = FALSE;
1867
1868 /* Add any DSN flags to the mail command */
1869
1870 if ((smtp_use_dsn) && (dsn_all_lasthop == FALSE))
1871 {
1872 if (dsn_ret == dsn_ret_hdrs)
1873 {
1874 strcpy(p, " RET=HDRS");
1875 while (*p) p++;
1876 }
1877 else if (dsn_ret == dsn_ret_full)
1878 {
1879 strcpy(p, " RET=FULL");
1880 while (*p) p++;
1881 }
1882 if (dsn_envid != NULL)
1883 {
1884 string_format(p, sizeof(buffer) - (p-buffer), " ENVID=%s", dsn_envid);
1885 while (*p) p++;
1886 }
1887 }
1888 #endif
1889
1890 /* If an authenticated_sender override has been specified for this transport
1891 instance, expand it. If the expansion is forced to fail, and there was already
1892 an authenticated_sender for this message, the original value will be used.
1893 Other expansion failures are serious. An empty result is ignored, but there is
1894 otherwise no check - this feature is expected to be used with LMTP and other
1895 cases where non-standard addresses (e.g. without domains) might be required. */
1896
1897 if (smtp_mail_auth_str(p, sizeof(buffer) - (p-buffer), addrlist, ob))
1898 {
1899 yield = ERROR;
1900 goto SEND_QUIT;
1901 }
1902
1903 /* From here until we send the DATA command, we can make use of PIPELINING
1904 if the server host supports it. The code has to be able to check the responses
1905 at any point, for when the buffer fills up, so we write it totally generally.
1906 When PIPELINING is off, each command written reports that it has flushed the
1907 buffer. */
1908
1909 pending_MAIL = TRUE; /* The block starts with MAIL */
1910
1911 rc = smtp_write_command(&outblock, smtp_use_pipelining,
1912 "MAIL FROM:<%s>%s\r\n", return_path, buffer);
1913 mail_command = string_copy(big_buffer); /* Save for later error message */
1914
1915 switch(rc)
1916 {
1917 case -1: /* Transmission error */
1918 goto SEND_FAILED;
1919
1920 case +1: /* Block was sent */
1921 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1922 ob->command_timeout))
1923 {
1924 if (errno == 0 && buffer[0] == '4')
1925 {
1926 errno = ERRNO_MAIL4XX;
1927 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1928 }
1929 goto RESPONSE_FAILED;
1930 }
1931 pending_MAIL = FALSE;
1932 break;
1933 }
1934
1935 /* Pass over all the relevant recipient addresses for this host, which are the
1936 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
1937 several before we have to read the responses for those seen so far. This
1938 checking is done by a subroutine because it also needs to be done at the end.
1939 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
1940 the next one if not all are sent.
1941
1942 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
1943 last address because we want to abort if any recipients have any kind of
1944 problem, temporary or permanent. We know that all recipient addresses will have
1945 the PENDING_DEFER status, because only one attempt is ever made, and we know
1946 that max_rcpt will be large, so all addresses will be done at once. */
1947
1948 for (addr = first_addr;
1949 address_count < max_rcpt && addr != NULL;
1950 addr = addr->next)
1951 {
1952 int count;
1953 BOOL no_flush;
1954
1955 #ifdef EXPERIMENTAL_DSN
1956 addr->dsn_aware = smtp_use_dsn ? dsn_support_yes : dsn_support_no;
1957 #endif
1958
1959 if (addr->transport_return != PENDING_DEFER) continue;
1960
1961 address_count++;
1962 no_flush = smtp_use_pipelining && (!mua_wrapper || addr->next != NULL);
1963
1964 #ifdef EXPERIMENTAL_DSN
1965 /* Add any DSN flags to the rcpt command and add to the sent string */
1966
1967 p = buffer;
1968 *p = 0;
1969
1970 if (smtp_use_dsn && (addr->dsn_flags & rf_dsnlasthop) != 1)
1971 {
1972 if ((addr->dsn_flags & rf_dsnflags) != 0)
1973 {
1974 int i;
1975 BOOL first = TRUE;
1976 strcpy(p, " NOTIFY=");
1977 while (*p) p++;
1978 for (i = 0; i < 4; i++)
1979 if ((addr->dsn_flags & rf_list[i]) != 0)
1980 {
1981 if (!first) *p++ = ',';
1982 first = FALSE;
1983 strcpy(p, rf_names[i]);
1984 while (*p) p++;
1985 }
1986 }
1987
1988 if (addr->dsn_orcpt != NULL)
1989 {
1990 string_format(p, sizeof(buffer) - (p-buffer), " ORCPT=%s",
1991 addr->dsn_orcpt);
1992 while (*p) p++;
1993 }
1994 }
1995 #endif
1996
1997
1998 /* Now send the RCPT command, and process outstanding responses when
1999 necessary. After a timeout on RCPT, we just end the function, leaving the
2000 yield as OK, because this error can often mean that there is a problem with
2001 just one address, so we don't want to delay the host. */
2002
2003 #ifdef EXPERIMENTAL_DSN
2004 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s%s\r\n",
2005 transport_rcpt_address(addr, tblock->rcpt_include_affixes), igquotstr, buffer);
2006 #else
2007 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s\r\n",
2008 transport_rcpt_address(addr, tblock->rcpt_include_affixes), igquotstr);
2009 #endif
2010
2011 if (count < 0) goto SEND_FAILED;
2012 if (count > 0)
2013 {
2014 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
2015 &sync_addr, host, count, ob->address_retry_include_sender,
2016 pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
2017 sizeof(buffer)))
2018 {
2019 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2020 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2021 break;
2022
2023 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2024 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2025 case 0: /* No 2xx or 5xx, but no probs */
2026 break;
2027
2028 case -1: goto END_OFF; /* Timeout on RCPT */
2029 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
2030 }
2031 pending_MAIL = FALSE; /* Dealt with MAIL */
2032 }
2033 } /* Loop for next address */
2034
2035 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
2036 permanently or temporarily. We should have flushed and synced after the last
2037 RCPT. */
2038
2039 if (mua_wrapper)
2040 {
2041 address_item *badaddr;
2042 for (badaddr = first_addr; badaddr != NULL; badaddr = badaddr->next)
2043 {
2044 if (badaddr->transport_return != PENDING_OK) break;
2045 }
2046 if (badaddr != NULL)
2047 {
2048 set_errno(addrlist, 0, badaddr->message, FAIL,
2049 testflag(badaddr, af_pass_message), NULL);
2050 ok = FALSE;
2051 }
2052 }
2053
2054 /* If ok is TRUE, we know we have got at least one good recipient, and must now
2055 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
2056 have a good recipient buffered up if we are pipelining. We don't want to waste
2057 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
2058 are pipelining. The responses are all handled by sync_responses(). */
2059
2060 if (ok || (smtp_use_pipelining && !mua_wrapper))
2061 {
2062 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
2063 if (count < 0) goto SEND_FAILED;
2064 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
2065 host, count, ob->address_retry_include_sender, pending_MAIL,
2066 ok? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
2067 {
2068 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2069 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2070 break;
2071
2072 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2073 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2074 case 0: break; /* No 2xx or 5xx, but no probs */
2075
2076 case -1: goto END_OFF; /* Timeout on RCPT */
2077 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2078 }
2079 }
2080
2081 /* Save the first address of the next batch. */
2082
2083 first_addr = addr;
2084
2085 /* If there were no good recipients (but otherwise there have been no
2086 problems), just set ok TRUE, since we have handled address-specific errors
2087 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
2088 for handling the SMTP dot-handling protocol, flagging to apply to headers as
2089 well as body. Set the appropriate timeout value to be used for each chunk.
2090 (Haven't been able to make it work using select() for writing yet.) */
2091
2092 if (!ok) ok = TRUE; else
2093 {
2094 sigalrm_seen = FALSE;
2095 transport_write_timeout = ob->data_timeout;
2096 smtp_command = US"sending data block"; /* For error messages */
2097 DEBUG(D_transport|D_v)
2098 debug_printf(" SMTP>> writing message and terminating \".\"\n");
2099 transport_count = 0;
2100
2101 #ifndef DISABLE_DKIM
2102 ok = dkim_transport_write_message(addrlist, inblock.sock,
2103 topt_use_crlf | topt_end_dot | topt_escape_headers |
2104 (tblock->body_only? topt_no_headers : 0) |
2105 (tblock->headers_only? topt_no_body : 0) |
2106 (tblock->return_path_add? topt_add_return_path : 0) |
2107 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
2108 (tblock->envelope_to_add? topt_add_envelope_to : 0),
2109 0, /* No size limit */
2110 tblock->add_headers, tblock->remove_headers,
2111 US".", US"..", /* Escaping strings */
2112 tblock->rewrite_rules, tblock->rewrite_existflags,
2113 ob->dkim_private_key, ob->dkim_domain, ob->dkim_selector,
2114 ob->dkim_canon, ob->dkim_strict, ob->dkim_sign_headers
2115 );
2116 #else
2117 ok = transport_write_message(addrlist, inblock.sock,
2118 topt_use_crlf | topt_end_dot | topt_escape_headers |
2119 (tblock->body_only? topt_no_headers : 0) |
2120 (tblock->headers_only? topt_no_body : 0) |
2121 (tblock->return_path_add? topt_add_return_path : 0) |
2122 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
2123 (tblock->envelope_to_add? topt_add_envelope_to : 0),
2124 0, /* No size limit */
2125 tblock->add_headers, tblock->remove_headers,
2126 US".", US"..", /* Escaping strings */
2127 tblock->rewrite_rules, tblock->rewrite_existflags);
2128 #endif
2129
2130 /* transport_write_message() uses write() because it is called from other
2131 places to write to non-sockets. This means that under some OS (e.g. Solaris)
2132 it can exit with "Broken pipe" as its error. This really means that the
2133 socket got closed at the far end. */
2134
2135 transport_write_timeout = 0; /* for subsequent transports */
2136
2137 /* Failure can either be some kind of I/O disaster (including timeout),
2138 or the failure of a transport filter or the expansion of added headers. */
2139
2140 if (!ok)
2141 {
2142 buffer[0] = 0; /* There hasn't been a response */
2143 goto RESPONSE_FAILED;
2144 }
2145
2146 /* We used to send the terminating "." explicitly here, but because of
2147 buffering effects at both ends of TCP/IP connections, you don't gain
2148 anything by keeping it separate, so it might as well go in the final
2149 data buffer for efficiency. This is now done by setting the topt_end_dot
2150 flag above. */
2151
2152 smtp_command = US"end of data";
2153
2154 #ifndef DISABLE_PRDR
2155 /* For PRDR we optionally get a partial-responses warning
2156 * followed by the individual responses, before going on with
2157 * the overall response. If we don't get the warning then deal
2158 * with per non-PRDR. */
2159 if(prdr_active)
2160 {
2161 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '3',
2162 ob->final_timeout);
2163 if (!ok && errno == 0)
2164 switch(buffer[0])
2165 {
2166 case '2': prdr_active = FALSE;
2167 ok = TRUE;
2168 break;
2169 case '4': errno = ERRNO_DATA4XX;
2170 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2171 break;
2172 }
2173 }
2174 else
2175 #endif
2176
2177 /* For non-PRDR SMTP, we now read a single response that applies to the
2178 whole message. If it is OK, then all the addresses have been delivered. */
2179
2180 if (!lmtp)
2181 {
2182 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2183 ob->final_timeout);
2184 if (!ok && errno == 0 && buffer[0] == '4')
2185 {
2186 errno = ERRNO_DATA4XX;
2187 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2188 }
2189 }
2190
2191 /* For LMTP, we get back a response for every RCPT command that we sent;
2192 some may be accepted and some rejected. For those that get a response, their
2193 status is fixed; any that are accepted have been handed over, even if later
2194 responses crash - at least, that's how I read RFC 2033.
2195
2196 If all went well, mark the recipient addresses as completed, record which
2197 host/IPaddress they were delivered to, and cut out RSET when sending another
2198 message down the same channel. Write the completed addresses to the journal
2199 now so that they are recorded in case there is a crash of hardware or
2200 software before the spool gets updated. Also record the final SMTP
2201 confirmation if needed (for SMTP only). */
2202
2203 if (ok)
2204 {
2205 int flag = '=';
2206 int delivery_time = (int)(time(NULL) - start_delivery_time);
2207 int len;
2208 host_item *thost;
2209 uschar *conf = NULL;
2210 send_rset = FALSE;
2211
2212 /* Make a copy of the host if it is local to this invocation
2213 of the transport. */
2214
2215 if (copy_host)
2216 {
2217 thost = store_get(sizeof(host_item));
2218 *thost = *host;
2219 thost->name = string_copy(host->name);
2220 thost->address = string_copy(host->address);
2221 }
2222 else thost = host;
2223
2224 /* Set up confirmation if needed - applies only to SMTP */
2225
2226 if (
2227 #ifndef EXPERIMENTAL_EVENT
2228 (log_extra_selector & LX_smtp_confirmation) != 0 &&
2229 #endif
2230 !lmtp
2231 )
2232 {
2233 uschar *s = string_printing(buffer);
2234 conf = (s == buffer)? (uschar *)string_copy(s) : s;
2235 }
2236
2237 /* Process all transported addresses - for LMTP or PRDR, read a status for
2238 each one. */
2239
2240 for (addr = addrlist; addr != first_addr; addr = addr->next)
2241 {
2242 if (addr->transport_return != PENDING_OK) continue;
2243
2244 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
2245 remaining addresses. Otherwise, it's a return code for just the one
2246 address. For temporary errors, add a retry item for the address so that
2247 it doesn't get tried again too soon. */
2248
2249 #ifndef DISABLE_PRDR
2250 if (lmtp || prdr_active)
2251 #else
2252 if (lmtp)
2253 #endif
2254 {
2255 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2256 ob->final_timeout))
2257 {
2258 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
2259 addr->message = string_sprintf(
2260 #ifndef DISABLE_PRDR
2261 "%s error after %s: %s", prdr_active ? "PRDR":"LMTP",
2262 #else
2263 "LMTP error after %s: %s",
2264 #endif
2265 big_buffer, string_printing(buffer));
2266 setflag(addr, af_pass_message); /* Allow message to go to user */
2267 if (buffer[0] == '5')
2268 addr->transport_return = FAIL;
2269 else
2270 {
2271 errno = ERRNO_DATA4XX;
2272 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2273 addr->transport_return = DEFER;
2274 #ifndef DISABLE_PRDR
2275 if (!prdr_active)
2276 #endif
2277 retry_add_item(addr, addr->address_retry_key, 0);
2278 }
2279 continue;
2280 }
2281 completed_address = TRUE; /* NOW we can set this flag */
2282 if ((log_extra_selector & LX_smtp_confirmation) != 0)
2283 {
2284 uschar *s = string_printing(buffer);
2285 conf = (s == buffer)? (uschar *)string_copy(s) : s;
2286 }
2287 }
2288
2289 /* SMTP, or success return from LMTP for this address. Pass back the
2290 actual host that was used. */
2291
2292 addr->transport_return = OK;
2293 addr->more_errno = delivery_time;
2294 addr->host_used = thost;
2295 addr->special_action = flag;
2296 addr->message = conf;
2297 #ifndef DISABLE_PRDR
2298 if (prdr_active) addr->flags |= af_prdr_used;
2299 #endif
2300 flag = '-';
2301
2302 #ifndef DISABLE_PRDR
2303 if (!prdr_active)
2304 #endif
2305 {
2306 /* Update the journal. For homonymic addresses, use the base address plus
2307 the transport name. See lots of comments in deliver.c about the reasons
2308 for the complications when homonyms are involved. Just carry on after
2309 write error, as it may prove possible to update the spool file later. */
2310
2311 if (testflag(addr, af_homonym))
2312 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2313 else
2314 sprintf(CS buffer, "%.500s\n", addr->unique);
2315
2316 DEBUG(D_deliver) debug_printf("journalling %s", buffer);
2317 len = Ustrlen(CS buffer);
2318 if (write(journal_fd, buffer, len) != len)
2319 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2320 "%s: %s", buffer, strerror(errno));
2321 }
2322 }
2323
2324 #ifndef DISABLE_PRDR
2325 if (prdr_active)
2326 {
2327 /* PRDR - get the final, overall response. For any non-success
2328 upgrade all the address statuses. */
2329 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2330 ob->final_timeout);
2331 if (!ok)
2332 {
2333 if(errno == 0 && buffer[0] == '4')
2334 {
2335 errno = ERRNO_DATA4XX;
2336 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2337 }
2338 for (addr = addrlist; addr != first_addr; addr = addr->next)
2339 if (buffer[0] == '5' || addr->transport_return == OK)
2340 addr->transport_return = PENDING_OK; /* allow set_errno action */
2341 goto RESPONSE_FAILED;
2342 }
2343
2344 /* Update the journal, or setup retry. */
2345 for (addr = addrlist; addr != first_addr; addr = addr->next)
2346 if (addr->transport_return == OK)
2347 {
2348 if (testflag(addr, af_homonym))
2349 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2350 else
2351 sprintf(CS buffer, "%.500s\n", addr->unique);
2352
2353 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s", buffer);
2354 len = Ustrlen(CS buffer);
2355 if (write(journal_fd, buffer, len) != len)
2356 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2357 "%s: %s", buffer, strerror(errno));
2358 }
2359 else if (addr->transport_return == DEFER)
2360 retry_add_item(addr, addr->address_retry_key, -2);
2361 }
2362 #endif
2363
2364 /* Ensure the journal file is pushed out to disk. */
2365
2366 if (EXIMfsync(journal_fd) < 0)
2367 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
2368 strerror(errno));
2369 }
2370 }
2371
2372
2373 /* Handle general (not specific to one address) failures here. The value of ok
2374 is used to skip over this code on the falling through case. A timeout causes a
2375 deferral. Other errors may defer or fail according to the response code, and
2376 may set up a special errno value, e.g. after connection chopped, which is
2377 assumed if errno == 0 and there is no text in the buffer. If control reaches
2378 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
2379 the problem is not related to this specific message. */
2380
2381 if (!ok)
2382 {
2383 int code;
2384
2385 RESPONSE_FAILED:
2386 save_errno = errno;
2387 message = NULL;
2388 send_quit = check_response(host, &save_errno, addrlist->more_errno,
2389 buffer, &code, &message, &pass_message);
2390 goto FAILED;
2391
2392 SEND_FAILED:
2393 save_errno = errno;
2394 code = '4';
2395 message = US string_sprintf("send() to %s [%s] failed: %s",
2396 host->name, host->address, strerror(save_errno));
2397 send_quit = FALSE;
2398 goto FAILED;
2399
2400 /* This label is jumped to directly when a TLS negotiation has failed,
2401 or was not done for a host for which it is required. Values will be set
2402 in message and save_errno, and setting_up will always be true. Treat as
2403 a temporary error. */
2404
2405 #ifdef SUPPORT_TLS
2406 TLS_FAILED:
2407 code = '4';
2408 #endif
2409
2410 /* If the failure happened while setting up the call, see if the failure was
2411 a 5xx response (this will either be on connection, or following HELO - a 5xx
2412 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
2413 never going to accept them. For other errors during setting up (timeouts or
2414 whatever), defer all addresses, and yield DEFER, so that the host is not
2415 tried again for a while. */
2416
2417 FAILED:
2418 ok = FALSE; /* For when reached by GOTO */
2419
2420 if (setting_up)
2421 {
2422 if (code == '5')
2423 set_errno(addrlist, save_errno, message, FAIL, pass_message, host);
2424 else
2425 {
2426 set_errno(addrlist, save_errno, message, DEFER, pass_message, host);
2427 yield = DEFER;
2428 }
2429 }
2430
2431 /* We want to handle timeouts after MAIL or "." and loss of connection after
2432 "." specially. They can indicate a problem with the sender address or with
2433 the contents of the message rather than a real error on the connection. These
2434 cases are treated in the same way as a 4xx response. This next bit of code
2435 does the classification. */
2436
2437 else
2438 {
2439 BOOL message_error;
2440
2441 switch(save_errno)
2442 {
2443 case 0:
2444 case ERRNO_MAIL4XX:
2445 case ERRNO_DATA4XX:
2446 message_error = TRUE;
2447 break;
2448
2449 case ETIMEDOUT:
2450 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
2451 Ustrncmp(smtp_command,"end ",4) == 0;
2452 break;
2453
2454 case ERRNO_SMTPCLOSED:
2455 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
2456 break;
2457
2458 default:
2459 message_error = FALSE;
2460 break;
2461 }
2462
2463 /* Handle the cases that are treated as message errors. These are:
2464
2465 (a) negative response or timeout after MAIL
2466 (b) negative response after DATA
2467 (c) negative response or timeout or dropped connection after "."
2468
2469 It won't be a negative response or timeout after RCPT, as that is dealt
2470 with separately above. The action in all cases is to set an appropriate
2471 error code for all the addresses, but to leave yield set to OK because the
2472 host itself has not failed. Of course, it might in practice have failed
2473 when we've had a timeout, but if so, we'll discover that at the next
2474 delivery attempt. For a temporary error, set the message_defer flag, and
2475 write to the logs for information if this is not the last host. The error
2476 for the last host will be logged as part of the address's log line. */
2477
2478 if (message_error)
2479 {
2480 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
2481 set_errno(addrlist, save_errno, message, (code == '5')? FAIL : DEFER,
2482 pass_message, host);
2483
2484 /* If there's an errno, the message contains just the identity of
2485 the host. */
2486
2487 if (code != '5') /* Anything other than 5 is treated as temporary */
2488 {
2489 if (save_errno > 0)
2490 message = US string_sprintf("%s: %s", message, strerror(save_errno));
2491 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
2492 msglog_line(host, message);
2493 *message_defer = TRUE;
2494 }
2495 }
2496
2497 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
2498 ".", or some other transportation error. We defer all addresses and yield
2499 DEFER, except for the case of failed add_headers expansion, or a transport
2500 filter failure, when the yield should be ERROR, to stop it trying other
2501 hosts. */
2502
2503 else
2504 {
2505 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
2506 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
2507 set_errno(addrlist, save_errno, message, DEFER, pass_message, host);
2508 }
2509 }
2510 }
2511
2512
2513 /* If all has gone well, send_quit will be set TRUE, implying we can end the
2514 SMTP session tidily. However, if there were too many addresses to send in one
2515 message (indicated by first_addr being non-NULL) we want to carry on with the
2516 rest of them. Also, it is desirable to send more than one message down the SMTP
2517 connection if there are several waiting, provided we haven't already sent so
2518 many as to hit the configured limit. The function transport_check_waiting looks
2519 for a waiting message and returns its id. Then transport_pass_socket tries to
2520 set up a continued delivery by passing the socket on to another process. The
2521 variable send_rset is FALSE if a message has just been successfully transfered.
2522
2523 If we are already sending down a continued channel, there may be further
2524 addresses not yet delivered that are aimed at the same host, but which have not
2525 been passed in this run of the transport. In this case, continue_more will be
2526 true, and all we should do is send RSET if necessary, and return, leaving the
2527 channel open.
2528
2529 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
2530 do not want to continue with other messages down the same channel, because that
2531 can lead to looping between two or more messages, all with the same,
2532 temporarily failing address(es). [The retry information isn't updated yet, so
2533 new processes keep on trying.] We probably also don't want to try more of this
2534 message's addresses either.
2535
2536 If we have started a TLS session, we have to end it before passing the
2537 connection to a new process. However, not all servers can handle this (Exim
2538 can), so we do not pass such a connection on if the host matches
2539 hosts_nopass_tls. */
2540
2541 DEBUG(D_transport)
2542 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
2543 "yield=%d first_address is %sNULL\n", ok, send_quit, send_rset,
2544 continue_more, yield, (first_addr == NULL)? "":"not ");
2545
2546 if (completed_address && ok && send_quit)
2547 {
2548 BOOL more;
2549 if (first_addr != NULL || continue_more ||
2550 (
2551 (tls_out.active < 0 ||
2552 verify_check_this_host(&(ob->hosts_nopass_tls), NULL, host->name,
2553 host->address, NULL) != OK)
2554 &&
2555 transport_check_waiting(tblock->name, host->name,
2556 tblock->connection_max_messages, new_message_id, &more)
2557 ))
2558 {
2559 uschar *msg;
2560 BOOL pass_message;
2561
2562 if (send_rset)
2563 {
2564 if (! (ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
2565 {
2566 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
2567 host->address, strerror(save_errno));
2568 send_quit = FALSE;
2569 }
2570 else if (! (ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2571 ob->command_timeout)))
2572 {
2573 int code;
2574 send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
2575 &pass_message);
2576 if (!send_quit)
2577 {
2578 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
2579 host->name, host->address, msg);
2580 }
2581 }
2582 }
2583
2584 /* Either RSET was not needed, or it succeeded */
2585
2586 if (ok)
2587 {
2588 if (first_addr != NULL) /* More addresses still to be sent */
2589 { /* in this run of the transport */
2590 continue_sequence++; /* Causes * in logging */
2591 goto SEND_MESSAGE;
2592 }
2593 if (continue_more) return yield; /* More addresses for another run */
2594
2595 /* Pass the socket to a new Exim process. Before doing so, we must shut
2596 down TLS. Not all MTAs allow for the continuation of the SMTP session
2597 when TLS is shut down. We test for this by sending a new EHLO. If we
2598 don't get a good response, we don't attempt to pass the socket on. */
2599
2600 #ifdef SUPPORT_TLS
2601 if (tls_out.active >= 0)
2602 {
2603 tls_close(FALSE, TRUE);
2604 if (smtps)
2605 ok = FALSE;
2606 else
2607 ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
2608 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2609 ob->command_timeout);
2610 }
2611 #endif
2612
2613 /* If the socket is successfully passed, we musn't send QUIT (or
2614 indeed anything!) from here. */
2615
2616 if (ok && transport_pass_socket(tblock->name, host->name, host->address,
2617 new_message_id, inblock.sock))
2618 {
2619 send_quit = FALSE;
2620 }
2621 }
2622
2623 /* If RSET failed and there are addresses left, they get deferred. */
2624
2625 else set_errno(first_addr, errno, msg, DEFER, FALSE, host);
2626 }
2627 }
2628
2629 /* End off tidily with QUIT unless the connection has died or the socket has
2630 been passed to another process. There has been discussion on the net about what
2631 to do after sending QUIT. The wording of the RFC suggests that it is necessary
2632 to wait for a response, but on the other hand, there isn't anything one can do
2633 with an error response, other than log it. Exim used to do that. However,
2634 further discussion suggested that it is positively advantageous not to wait for
2635 the response, but to close the session immediately. This is supposed to move
2636 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
2637 load from the server. (Hosts that are both servers and clients may not see much
2638 difference, of course.) Further discussion indicated that this was safe to do
2639 on Unix systems which have decent implementations of TCP/IP that leave the
2640 connection around for a while (TIME_WAIT) after the application has gone away.
2641 This enables the response sent by the server to be properly ACKed rather than
2642 timed out, as can happen on broken TCP/IP implementations on other OS.
2643
2644 This change is being made on 31-Jul-98. After over a year of trouble-free
2645 operation, the old commented-out code was removed on 17-Sep-99. */
2646
2647 SEND_QUIT:
2648 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2649
2650 END_OFF:
2651
2652 #ifdef SUPPORT_TLS
2653 tls_close(FALSE, TRUE);
2654 #endif
2655
2656 /* Close the socket, and return the appropriate value, first setting
2657 works because the NULL setting is passed back to the calling process, and
2658 remote_max_parallel is forced to 1 when delivering over an existing connection,
2659
2660 If all went well and continue_more is set, we shouldn't actually get here if
2661 there are further addresses, as the return above will be taken. However,
2662 writing RSET might have failed, or there may be other addresses whose hosts are
2663 specified in the transports, and therefore not visible at top level, in which
2664 case continue_more won't get set. */
2665
2666 (void)close(inblock.sock);
2667
2668 #ifdef EXPERIMENTAL_EVENT
2669 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
2670 #endif
2671
2672 continue_transport = NULL;
2673 continue_hostname = NULL;
2674 return yield;
2675 }
2676
2677
2678
2679
2680 /*************************************************
2681 * Closedown entry point *
2682 *************************************************/
2683
2684 /* This function is called when exim is passed an open smtp channel
2685 from another incarnation, but the message which it has been asked
2686 to deliver no longer exists. The channel is on stdin.
2687
2688 We might do fancy things like looking for another message to send down
2689 the channel, but if the one we sought has gone, it has probably been
2690 delivered by some other process that itself will seek further messages,
2691 so just close down our connection.
2692
2693 Argument: pointer to the transport instance block
2694 Returns: nothing
2695 */
2696
2697 void
2698 smtp_transport_closedown(transport_instance *tblock)
2699 {
2700 smtp_transport_options_block *ob =
2701 (smtp_transport_options_block *)(tblock->options_block);
2702 smtp_inblock inblock;
2703 smtp_outblock outblock;
2704 uschar buffer[256];
2705 uschar inbuffer[4096];
2706 uschar outbuffer[16];
2707
2708 inblock.sock = fileno(stdin);
2709 inblock.buffer = inbuffer;
2710 inblock.buffersize = sizeof(inbuffer);
2711 inblock.ptr = inbuffer;
2712 inblock.ptrend = inbuffer;
2713
2714 outblock.sock = inblock.sock;
2715 outblock.buffersize = sizeof(outbuffer);
2716 outblock.buffer = outbuffer;
2717 outblock.ptr = outbuffer;
2718 outblock.cmd_count = 0;
2719 outblock.authenticating = FALSE;
2720
2721 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2722 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2723 ob->command_timeout);
2724 (void)close(inblock.sock);
2725 }
2726
2727
2728
2729 /*************************************************
2730 * Prepare addresses for delivery *
2731 *************************************************/
2732
2733 /* This function is called to flush out error settings from previous delivery
2734 attempts to other hosts. It also records whether we got here via an MX record
2735 or not in the more_errno field of the address. We are interested only in
2736 addresses that are still marked DEFER - others may have got delivered to a
2737 previously considered IP address. Set their status to PENDING_DEFER to indicate
2738 which ones are relevant this time.
2739
2740 Arguments:
2741 addrlist the list of addresses
2742 host the host we are delivering to
2743
2744 Returns: the first address for this delivery
2745 */
2746
2747 static address_item *
2748 prepare_addresses(address_item *addrlist, host_item *host)
2749 {
2750 address_item *first_addr = NULL;
2751 address_item *addr;
2752 for (addr = addrlist; addr != NULL; addr = addr->next)
2753 {
2754 if (addr->transport_return != DEFER) continue;
2755 if (first_addr == NULL) first_addr = addr;
2756 addr->transport_return = PENDING_DEFER;
2757 addr->basic_errno = 0;
2758 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
2759 addr->message = NULL;
2760 #ifdef SUPPORT_TLS
2761 addr->cipher = NULL;
2762 addr->ourcert = NULL;
2763 addr->peercert = NULL;
2764 addr->peerdn = NULL;
2765 addr->ocsp = OCSP_NOT_REQ;
2766 #endif
2767 }
2768 return first_addr;
2769 }
2770
2771
2772
2773 /*************************************************
2774 * Main entry point *
2775 *************************************************/
2776
2777 /* See local README for interface details. As this is a remote transport, it is
2778 given a chain of addresses to be delivered in one connection, if possible. It
2779 always returns TRUE, indicating that each address has its own independent
2780 status set, except if there is a setting up problem, in which case it returns
2781 FALSE. */
2782
2783 BOOL
2784 smtp_transport_entry(
2785 transport_instance *tblock, /* data for this instantiation */
2786 address_item *addrlist) /* addresses we are working on */
2787 {
2788 int cutoff_retry;
2789 int port;
2790 int hosts_defer = 0;
2791 int hosts_fail = 0;
2792 int hosts_looked_up = 0;
2793 int hosts_retry = 0;
2794 int hosts_serial = 0;
2795 int hosts_total = 0;
2796 int total_hosts_tried = 0;
2797 address_item *addr;
2798 BOOL expired = TRUE;
2799 BOOL continuing = continue_hostname != NULL;
2800 uschar *expanded_hosts = NULL;
2801 uschar *pistring;
2802 uschar *tid = string_sprintf("%s transport", tblock->name);
2803 smtp_transport_options_block *ob =
2804 (smtp_transport_options_block *)(tblock->options_block);
2805 host_item *hostlist = addrlist->host_list;
2806 host_item *host = NULL;
2807
2808 DEBUG(D_transport)
2809 {
2810 debug_printf("%s transport entered\n", tblock->name);
2811 for (addr = addrlist; addr != NULL; addr = addr->next)
2812 debug_printf(" %s\n", addr->address);
2813 if (continuing) debug_printf("already connected to %s [%s]\n",
2814 continue_hostname, continue_host_address);
2815 }
2816
2817 /* Set the flag requesting that these hosts be added to the waiting
2818 database if the delivery fails temporarily or if we are running with
2819 queue_smtp or a 2-stage queue run. This gets unset for certain
2820 kinds of error, typically those that are specific to the message. */
2821
2822 update_waiting = TRUE;
2823
2824 /* If a host list is not defined for the addresses - they must all have the
2825 same one in order to be passed to a single transport - or if the transport has
2826 a host list with hosts_override set, use the host list supplied with the
2827 transport. It is an error for this not to exist. */
2828
2829 if (hostlist == NULL || (ob->hosts_override && ob->hosts != NULL))
2830 {
2831 if (ob->hosts == NULL)
2832 {
2833 addrlist->message = string_sprintf("%s transport called with no hosts set",
2834 tblock->name);
2835 addrlist->transport_return = PANIC;
2836 return FALSE; /* Only top address has status */
2837 }
2838
2839 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
2840 ob->hosts);
2841
2842 /* If the transport's host list contains no '$' characters, and we are not
2843 randomizing, it is fixed and therefore a chain of hosts can be built once
2844 and for all, and remembered for subsequent use by other calls to this
2845 transport. If, on the other hand, the host list does contain '$', or we are
2846 randomizing its order, we have to rebuild it each time. In the fixed case,
2847 as the hosts string will never be used again, it doesn't matter that we
2848 replace all the : characters with zeros. */
2849
2850 if (ob->hostlist == NULL)
2851 {
2852 uschar *s = ob->hosts;
2853
2854 if (Ustrchr(s, '$') != NULL)
2855 {
2856 expanded_hosts = expand_string(s);
2857 if (expanded_hosts == NULL)
2858 {
2859 addrlist->message = string_sprintf("failed to expand list of hosts "
2860 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
2861 addrlist->transport_return = search_find_defer? DEFER : PANIC;
2862 return FALSE; /* Only top address has status */
2863 }
2864 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
2865 "\"%s\"\n", s, expanded_hosts);
2866 s = expanded_hosts;
2867 }
2868 else
2869 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
2870
2871 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
2872
2873 /* Check that the expansion yielded something useful. */
2874 if (hostlist == NULL)
2875 {
2876 addrlist->message =
2877 string_sprintf("%s transport has empty hosts setting", tblock->name);
2878 addrlist->transport_return = PANIC;
2879 return FALSE; /* Only top address has status */
2880 }
2881
2882 /* If there was no expansion of hosts, save the host list for
2883 next time. */
2884
2885 if (expanded_hosts == NULL) ob->hostlist = hostlist;
2886 }
2887
2888 /* This is not the first time this transport has been run in this delivery;
2889 the host list was built previously. */
2890
2891 else hostlist = ob->hostlist;
2892 }
2893
2894 /* The host list was supplied with the address. If hosts_randomize is set, we
2895 must sort it into a random order if it did not come from MX records and has not
2896 already been randomized (but don't bother if continuing down an existing
2897 connection). */
2898
2899 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continuing)
2900 {
2901 host_item *newlist = NULL;
2902 while (hostlist != NULL)
2903 {
2904 host_item *h = hostlist;
2905 hostlist = hostlist->next;
2906
2907 h->sort_key = random_number(100);
2908
2909 if (newlist == NULL)
2910 {
2911 h->next = NULL;
2912 newlist = h;
2913 }
2914 else if (h->sort_key < newlist->sort_key)
2915 {
2916 h->next = newlist;
2917 newlist = h;
2918 }
2919 else
2920 {
2921 host_item *hh = newlist;
2922 while (hh->next != NULL)
2923 {
2924 if (h->sort_key < hh->next->sort_key) break;
2925 hh = hh->next;
2926 }
2927 h->next = hh->next;
2928 hh->next = h;
2929 }
2930 }
2931
2932 hostlist = addrlist->host_list = newlist;
2933 }
2934
2935
2936 /* Sort out the default port. */
2937
2938 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
2939
2940
2941 /* For each host-plus-IP-address on the list:
2942
2943 . If this is a continued delivery and the host isn't the one with the
2944 current connection, skip.
2945
2946 . If the status is unusable (i.e. previously failed or retry checked), skip.
2947
2948 . If no IP address set, get the address, either by turning the name into
2949 an address, calling gethostbyname if gethostbyname is on, or by calling
2950 the DNS. The DNS may yield multiple addresses, in which case insert the
2951 extra ones into the list.
2952
2953 . Get the retry data if not previously obtained for this address and set the
2954 field which remembers the state of this address. Skip if the retry time is
2955 not reached. If not, remember whether retry data was found. The retry string
2956 contains both the name and the IP address.
2957
2958 . Scan the list of addresses and mark those whose status is DEFER as
2959 PENDING_DEFER. These are the only ones that will be processed in this cycle
2960 of the hosts loop.
2961
2962 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
2963 Some addresses may be successfully delivered, others may fail, and yet
2964 others may get temporary errors and so get marked DEFER.
2965
2966 . The return from the delivery attempt is OK if a connection was made and a
2967 valid SMTP dialogue was completed. Otherwise it is DEFER.
2968
2969 . If OK, add a "remove" retry item for this host/IPaddress, if any.
2970
2971 . If fail to connect, or other defer state, add a retry item.
2972
2973 . If there are any addresses whose status is still DEFER, carry on to the
2974 next host/IPaddress, unless we have tried the number of hosts given
2975 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
2976 there is some fancy logic for hosts_max_try that means its limit can be
2977 overstepped in some circumstances.
2978
2979 If we get to the end of the list, all hosts have deferred at least one address,
2980 or not reached their retry times. If delay_after_cutoff is unset, it requests a
2981 delivery attempt to those hosts whose last try was before the arrival time of
2982 the current message. To cope with this, we have to go round the loop a second
2983 time. After that, set the status and error data for any addresses that haven't
2984 had it set already. */
2985
2986 for (cutoff_retry = 0; expired &&
2987 cutoff_retry < ((ob->delay_after_cutoff)? 1 : 2);
2988 cutoff_retry++)
2989 {
2990 host_item *nexthost = NULL;
2991 int unexpired_hosts_tried = 0;
2992
2993 for (host = hostlist;
2994 host != NULL &&
2995 unexpired_hosts_tried < ob->hosts_max_try &&
2996 total_hosts_tried < ob->hosts_max_try_hardlimit;
2997 host = nexthost)
2998 {
2999 int rc;
3000 int host_af;
3001 uschar *rs;
3002 BOOL serialized = FALSE;
3003 BOOL host_is_expired = FALSE;
3004 BOOL message_defer = FALSE;
3005 BOOL ifchanges = FALSE;
3006 BOOL some_deferred = FALSE;
3007 address_item *first_addr = NULL;
3008 uschar *interface = NULL;
3009 uschar *retry_host_key = NULL;
3010 uschar *retry_message_key = NULL;
3011 uschar *serialize_key = NULL;
3012
3013 /* Default next host is next host. :-) But this can vary if the
3014 hosts_max_try limit is hit (see below). It may also be reset if a host
3015 address is looked up here (in case the host was multihomed). */
3016
3017 nexthost = host->next;
3018
3019 /* If the address hasn't yet been obtained from the host name, look it up
3020 now, unless the host is already marked as unusable. If it is marked as
3021 unusable, it means that the router was unable to find its IP address (in
3022 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
3023 the lookup failed last time. We don't get this far if *all* MX records
3024 point to non-existent hosts; that is treated as a hard error.
3025
3026 We can just skip this host entirely. When the hosts came from the router,
3027 the address will timeout based on the other host(s); when the address is
3028 looked up below, there is an explicit retry record added.
3029
3030 Note that we mustn't skip unusable hosts if the address is not unset; they
3031 may be needed as expired hosts on the 2nd time round the cutoff loop. */
3032
3033 if (host->address == NULL)
3034 {
3035 int new_port, flags;
3036 host_item *hh;
3037 uschar *canonical_name;
3038
3039 if (host->status >= hstatus_unusable)
3040 {
3041 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
3042 host->name);
3043 continue;
3044 }
3045
3046 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
3047
3048 /* The host name is permitted to have an attached port. Find it, and
3049 strip it from the name. Just remember it for now. */
3050
3051 new_port = host_item_get_port(host);
3052
3053 /* Count hosts looked up */
3054
3055 hosts_looked_up++;
3056
3057 /* Find by name if so configured, or if it's an IP address. We don't
3058 just copy the IP address, because we need the test-for-local to happen. */
3059
3060 flags = HOST_FIND_BY_A;
3061 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
3062 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
3063
3064 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
3065 rc = host_find_byname(host, NULL, flags, &canonical_name, TRUE);
3066 else
3067 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
3068 ob->dnssec_request_domains, ob->dnssec_require_domains,
3069 &canonical_name, NULL);
3070
3071 /* Update the host (and any additional blocks, resulting from
3072 multihoming) with a host-specific port, if any. */
3073
3074 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
3075
3076 /* Failure to find the host at this time (usually DNS temporary failure)
3077 is really a kind of routing failure rather than a transport failure.
3078 Therefore we add a retry item of the routing kind, not to stop us trying
3079 to look this name up here again, but to ensure the address gets timed
3080 out if the failures go on long enough. A complete failure at this point
3081 commonly points to a configuration error, but the best action is still
3082 to carry on for the next host. */
3083
3084 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
3085 {
3086 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
3087 expired = FALSE;
3088 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
3089 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
3090 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
3091 host->status = hstatus_unusable;
3092
3093 for (addr = addrlist; addr != NULL; addr = addr->next)
3094 {
3095 if (addr->transport_return != DEFER) continue;
3096 addr->basic_errno = ERRNO_UNKNOWNHOST;
3097 addr->message =
3098 string_sprintf("failed to lookup IP address for %s", host->name);
3099 }
3100 continue;
3101 }
3102
3103 /* If the host is actually the local host, we may have a problem, or
3104 there may be some cunning configuration going on. In the problem case,
3105 log things and give up. The default transport status is already DEFER. */
3106
3107 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
3108 {
3109 for (addr = addrlist; addr != NULL; addr = addr->next)
3110 {
3111 addr->basic_errno = 0;
3112 addr->message = string_sprintf("%s transport found host %s to be "
3113 "local", tblock->name, host->name);
3114 }
3115 goto END_TRANSPORT;
3116 }
3117 } /* End of block for IP address lookup */
3118
3119 /* If this is a continued delivery, we are interested only in the host
3120 which matches the name of the existing open channel. The check is put
3121 here after the local host lookup, in case the name gets expanded as a
3122 result of the lookup. Set expired FALSE, to save the outer loop executing
3123 twice. */
3124
3125 if (continuing && (Ustrcmp(continue_hostname, host->name) != 0 ||
3126 Ustrcmp(continue_host_address, host->address) != 0))
3127 {
3128 expired = FALSE;
3129 continue; /* With next host */
3130 }
3131
3132 /* Reset the default next host in case a multihomed host whose addresses
3133 are not looked up till just above added to the host list. */
3134
3135 nexthost = host->next;
3136
3137 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
3138 domain is in queue_smtp_domains, we don't actually want to attempt any
3139 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
3140 there is a lookup defer in queue_smtp_domains, proceed as if the domain
3141 were not in it. We don't want to hold up all SMTP deliveries! Except when
3142 doing a two-stage queue run, don't do this if forcing. */
3143
3144 if ((!deliver_force || queue_2stage) && (queue_smtp ||
3145 match_isinlist(addrlist->domain, &queue_smtp_domains, 0,
3146 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
3147 {
3148 expired = FALSE;
3149 for (addr = addrlist; addr != NULL; addr = addr->next)
3150 {
3151 if (addr->transport_return != DEFER) continue;
3152 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
3153 }
3154 continue; /* With next host */
3155 }
3156
3157 /* Count hosts being considered - purely for an intelligent comment
3158 if none are usable. */
3159
3160 hosts_total++;
3161
3162 /* Set $host and $host address now in case they are needed for the
3163 interface expansion or the serialize_hosts check; they remain set if an
3164 actual delivery happens. */
3165
3166 deliver_host = host->name;
3167 deliver_host_address = host->address;
3168 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
3169 : host->dnssec == DS_NO ? US"no"
3170 : US"";
3171
3172 /* Set up a string for adding to the retry key if the port number is not
3173 the standard SMTP port. A host may have its own port setting that overrides
3174 the default. */
3175
3176 pistring = string_sprintf(":%d", (host->port == PORT_NONE)?
3177 port : host->port);
3178 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
3179
3180 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
3181 string changes upon expansion, we must add it to the key that is used for
3182 retries, because connections to the same host from a different interface
3183 should be treated separately. */
3184
3185 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET : AF_INET6;
3186 if (!smtp_get_interface(ob->interface, host_af, addrlist, &ifchanges,
3187 &interface, tid))
3188 return FALSE;
3189 if (ifchanges) pistring = string_sprintf("%s/%s", pistring, interface);
3190
3191 /* The first time round the outer loop, check the status of the host by
3192 inspecting the retry data. The second time round, we are interested only
3193 in expired hosts that haven't been tried since this message arrived. */
3194
3195 if (cutoff_retry == 0)
3196 {
3197 /* Ensure the status of the address is set by checking retry data if
3198 necessary. There maybe host-specific retry data (applicable to all
3199 messages) and also data for retries of a specific message at this host.
3200 If either of these retry records are actually read, the keys used are
3201 returned to save recomputing them later. */
3202
3203 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
3204 ob->retry_include_ip_address, &retry_host_key, &retry_message_key);
3205
3206 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
3207 (host->address == NULL)? US"" : host->address, pistring,
3208 (host->status == hstatus_usable)? "usable" :
3209 (host->status == hstatus_unusable)? "unusable" :
3210 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
3211
3212 /* Skip this address if not usable at this time, noting if it wasn't
3213 actually expired, both locally and in the address. */
3214
3215 switch (host->status)
3216 {
3217 case hstatus_unusable:
3218 expired = FALSE;
3219 setflag(addrlist, af_retry_skipped);
3220 /* Fall through */
3221
3222 case hstatus_unusable_expired:
3223 switch (host->why)
3224 {
3225 case hwhy_retry: hosts_retry++; break;
3226 case hwhy_failed: hosts_fail++; break;
3227 case hwhy_deferred: hosts_defer++; break;
3228 }
3229
3230 /* If there was a retry message key, implying that previously there
3231 was a message-specific defer, we don't want to update the list of
3232 messages waiting for these hosts. */
3233
3234 if (retry_message_key != NULL) update_waiting = FALSE;
3235 continue; /* With the next host or IP address */
3236 }
3237 }
3238
3239 /* Second time round the loop: if the address is set but expired, and
3240 the message is newer than the last try, let it through. */
3241
3242 else
3243 {
3244 if (host->address == NULL ||
3245 host->status != hstatus_unusable_expired ||
3246 host->last_try > received_time)
3247 continue;
3248 DEBUG(D_transport)
3249 debug_printf("trying expired host %s [%s]%s\n",
3250 host->name, host->address, pistring);
3251 host_is_expired = TRUE;
3252 }
3253
3254 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
3255 it remains TRUE only if all hosts are expired and none are actually tried.
3256 */
3257
3258 expired = FALSE;
3259
3260 /* If this host is listed as one to which access must be serialized,
3261 see if another Exim process has a connection to it, and if so, skip
3262 this host. If not, update the database to record our connection to it
3263 and remember this for later deletion. Do not do any of this if we are
3264 sending the message down a pre-existing connection. */
3265
3266 if (!continuing &&
3267 verify_check_this_host(&(ob->serialize_hosts), NULL, host->name,
3268 host->address, NULL) == OK)
3269 {
3270 serialize_key = string_sprintf("host-serialize-%s", host->name);
3271 if (!enq_start(serialize_key))
3272 {
3273 DEBUG(D_transport)
3274 debug_printf("skipping host %s because another Exim process "
3275 "is connected to it\n", host->name);
3276 hosts_serial++;
3277 continue;
3278 }
3279 serialized = TRUE;
3280 }
3281
3282 /* OK, we have an IP address that is not waiting for its retry time to
3283 arrive (it might be expired) OR (second time round the loop) we have an
3284 expired host that hasn't been tried since the message arrived. Have a go
3285 at delivering the message to it. First prepare the addresses by flushing
3286 out the result of previous attempts, and finding the first address that
3287 is still to be delivered. */
3288
3289 first_addr = prepare_addresses(addrlist, host);
3290
3291 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
3292 message_id, host->name, host->address, addrlist->address,
3293 (addrlist->next == NULL)? "" : ", ...");
3294
3295 set_process_info("delivering %s to %s [%s] (%s%s)",
3296 message_id, host->name, host->address, addrlist->address,
3297 (addrlist->next == NULL)? "" : ", ...");
3298
3299 /* This is not for real; don't do the delivery. If there are
3300 any remaining hosts, list them. */
3301
3302 if (dont_deliver)
3303 {
3304 host_item *host2;
3305 set_errno(addrlist, 0, NULL, OK, FALSE, NULL);
3306 for (addr = addrlist; addr != NULL; addr = addr->next)
3307 {
3308 addr->host_used = host;
3309 addr->special_action = '*';
3310 addr->message = US"delivery bypassed by -N option";
3311 }
3312 DEBUG(D_transport)
3313 {
3314 debug_printf("*** delivery by %s transport bypassed by -N option\n"
3315 "*** host and remaining hosts:\n", tblock->name);
3316 for (host2 = host; host2 != NULL; host2 = host2->next)
3317 debug_printf(" %s [%s]\n", host2->name,
3318 (host2->address == NULL)? US"unset" : host2->address);
3319 }
3320 rc = OK;
3321 }
3322
3323 /* This is for real. If the host is expired, we don't count it for
3324 hosts_max_retry. This ensures that all hosts must expire before an address
3325 is timed out, unless hosts_max_try_hardlimit (which protects against
3326 lunatic DNS configurations) is reached.
3327
3328 If the host is not expired and we are about to hit the hosts_max_retry
3329 limit, check to see if there is a subsequent hosts with a different MX
3330 value. If so, make that the next host, and don't count this one. This is a
3331 heuristic to make sure that different MXs do get tried. With a normal kind
3332 of retry rule, they would get tried anyway when the earlier hosts were
3333 delayed, but if the domain has a "retry every time" type of rule - as is
3334 often used for the the very large ISPs, that won't happen. */
3335
3336 else
3337 {
3338 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
3339 {
3340 host_item *h;
3341 DEBUG(D_transport)
3342 debug_printf("hosts_max_try limit reached with this host\n");
3343 for (h = host; h != NULL; h = h->next)
3344 if (h->mx != host->mx) break;
3345 if (h != NULL)
3346 {
3347 nexthost = h;
3348 unexpired_hosts_tried--;
3349 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
3350 "and will be tried\n");
3351 }
3352 }
3353
3354 /* Attempt the delivery. */
3355
3356 total_hosts_tried++;
3357 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
3358 expanded_hosts != NULL, &message_defer, FALSE);
3359
3360 /* Yield is one of:
3361 OK => connection made, each address contains its result;
3362 message_defer is set for message-specific defers (when all
3363 recipients are marked defer)
3364 DEFER => there was a non-message-specific delivery problem;
3365 ERROR => there was a problem setting up the arguments for a filter,
3366 or there was a problem with expanding added headers
3367 */
3368
3369 /* If the result is not OK, there was a non-message-specific problem.
3370 If the result is DEFER, we need to write to the logs saying what happened
3371 for this particular host, except in the case of authentication and TLS
3372 failures, where the log has already been written. If all hosts defer a
3373 general message is written at the end. */
3374
3375 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL &&
3376 first_addr->basic_errno != ERRNO_TLSFAILURE)
3377 write_logs(first_addr, host);
3378
3379 #ifdef EXPERIMENTAL_EVENT
3380 if (rc == DEFER)
3381 deferred_event_raise(first_addr, host);
3382 #endif
3383
3384 /* If STARTTLS was accepted, but there was a failure in setting up the
3385 TLS session (usually a certificate screwup), and the host is not in
3386 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
3387 TLS forcibly turned off. We have to start from scratch with a new SMTP
3388 connection. That's why the retry is done from here, not from within
3389 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
3390 session, so the in-clear transmission after those errors, if permitted,
3391 happens inside smtp_deliver().] */
3392
3393 #ifdef SUPPORT_TLS
3394 if ( rc == DEFER
3395 && first_addr->basic_errno == ERRNO_TLSFAILURE
3396 && ob->tls_tempfail_tryclear
3397 && verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
3398 host->address, NULL) != OK
3399 )
3400 {
3401 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
3402 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
3403 first_addr = prepare_addresses(addrlist, host);
3404 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
3405 expanded_hosts != NULL, &message_defer, TRUE);
3406 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
3407 write_logs(first_addr, host);
3408 # ifdef EXPERIMENTAL_EVENT
3409 if (rc == DEFER)
3410 deferred_event_raise(first_addr, host);
3411 # endif
3412 }
3413 #endif /*SUPPORT_TLS*/
3414 }
3415
3416 /* Delivery attempt finished */
3417
3418 rs = (rc == OK)? US"OK" : (rc == DEFER)? US"DEFER" : (rc == ERROR)?
3419 US"ERROR" : US"?";
3420
3421 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
3422 message_id, host->name, host->address, addrlist->address,
3423 (addrlist->next == NULL)? "" : " (& others)", rs);
3424
3425 /* Release serialization if set up */
3426
3427 if (serialized) enq_end(serialize_key);
3428
3429 /* If the result is DEFER, or if a host retry record is known to exist, we
3430 need to add an item to the retry chain for updating the retry database
3431 at the end of delivery. We only need to add the item to the top address,
3432 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
3433 for any other delivery attempts using the same address. (It is copied into
3434 the unusable tree at the outer level, so even if different address blocks
3435 contain the same address, it still won't get tried again.) */
3436
3437 if (rc == DEFER || retry_host_key != NULL)
3438 {
3439 int delete_flag = (rc != DEFER)? rf_delete : 0;
3440 if (retry_host_key == NULL)
3441 {
3442 retry_host_key = ob->retry_include_ip_address?
3443 string_sprintf("T:%S:%s%s", host->name, host->address, pistring) :
3444 string_sprintf("T:%S%s", host->name, pistring);
3445 }
3446
3447 /* If a delivery of another message over an existing SMTP connection
3448 yields DEFER, we do NOT set up retry data for the host. This covers the
3449 case when there are delays in routing the addresses in the second message
3450 that are so long that the server times out. This is alleviated by not
3451 routing addresses that previously had routing defers when handling an
3452 existing connection, but even so, this case may occur (e.g. if a
3453 previously happily routed address starts giving routing defers). If the
3454 host is genuinely down, another non-continued message delivery will
3455 notice it soon enough. */
3456
3457 if (delete_flag != 0 || !continuing)
3458 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
3459
3460 /* We may have tried an expired host, if its retry time has come; ensure
3461 the status reflects the expiry for the benefit of any other addresses. */
3462
3463 if (rc == DEFER)
3464 {
3465 host->status = (host_is_expired)?
3466 hstatus_unusable_expired : hstatus_unusable;
3467 host->why = hwhy_deferred;
3468 }
3469 }
3470
3471 /* If message_defer is set (host was OK, but every recipient got deferred
3472 because of some message-specific problem), or if that had happened
3473 previously so that a message retry key exists, add an appropriate item
3474 to the retry chain. Note that if there was a message defer but now there is
3475 a host defer, the message defer record gets deleted. That seems perfectly
3476 reasonable. Also, stop the message from being remembered as waiting
3477 for specific hosts. */
3478
3479 if (message_defer || retry_message_key != NULL)
3480 {
3481 int delete_flag = message_defer? 0 : rf_delete;
3482 if (retry_message_key == NULL)
3483 {
3484 retry_message_key = ob->retry_include_ip_address?
3485 string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
3486 message_id) :
3487 string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
3488 }
3489 retry_add_item(addrlist, retry_message_key,
3490 rf_message | rf_host | delete_flag);
3491 update_waiting = FALSE;
3492 }
3493
3494 /* Any return other than DEFER (that is, OK or ERROR) means that the
3495 addresses have got their final statuses filled in for this host. In the OK
3496 case, see if any of them are deferred. */
3497
3498 if (rc == OK)
3499 {
3500 for (addr = addrlist; addr != NULL; addr = addr->next)
3501 {
3502 if (addr->transport_return == DEFER)
3503 {
3504 some_deferred = TRUE;
3505 break;
3506 }
3507 }
3508 }
3509
3510 /* If no addresses deferred or the result was ERROR, return. We do this for
3511 ERROR because a failing filter set-up or add_headers expansion is likely to
3512 fail for any host we try. */
3513
3514 if (rc == ERROR || (rc == OK && !some_deferred))
3515 {
3516 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3517 return TRUE; /* Each address has its status */
3518 }
3519
3520 /* If the result was DEFER or some individual addresses deferred, let
3521 the loop run to try other hosts with the deferred addresses, except for the
3522 case when we were trying to deliver down an existing channel and failed.
3523 Don't try any other hosts in this case. */
3524
3525 if (continuing) break;
3526
3527 /* If the whole delivery, or some individual addresses, were deferred and
3528 there are more hosts that could be tried, do not count this host towards
3529 the hosts_max_try limit if the age of the message is greater than the
3530 maximum retry time for this host. This means we may try try all hosts,
3531 ignoring the limit, when messages have been around for some time. This is
3532 important because if we don't try all hosts, the address will never time
3533 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
3534
3535 if ((rc == DEFER || some_deferred) && nexthost != NULL)
3536 {
3537 BOOL timedout;
3538 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
3539
3540 if (retry != NULL && retry->rules != NULL)
3541 {
3542 retry_rule *last_rule;
3543 for (last_rule = retry->rules;
3544 last_rule->next != NULL;
3545 last_rule = last_rule->next);
3546 timedout = time(NULL) - received_time > last_rule->timeout;
3547 }
3548 else timedout = TRUE; /* No rule => timed out */
3549
3550 if (timedout)
3551 {
3552 unexpired_hosts_tried--;
3553 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
3554 "hosts_max_try (message older than host's retry time)\n");
3555 }
3556 }
3557 } /* End of loop for trying multiple hosts. */
3558
3559 /* This is the end of the loop that repeats iff expired is TRUE and
3560 ob->delay_after_cutoff is FALSE. The second time round we will
3561 try those hosts that haven't been tried since the message arrived. */
3562
3563 DEBUG(D_transport)
3564 {
3565 debug_printf("all IP addresses skipped or deferred at least one address\n");
3566 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
3567 debug_printf("retrying IP addresses not tried since message arrived\n");
3568 }
3569 }
3570
3571
3572 /* Get here if all IP addresses are skipped or defer at least one address. In
3573 MUA wrapper mode, this will happen only for connection or other non-message-
3574 specific failures. Force the delivery status for all addresses to FAIL. */
3575
3576 if (mua_wrapper)
3577 {
3578 for (addr = addrlist; addr != NULL; addr = addr->next)
3579 addr->transport_return = FAIL;
3580 goto END_TRANSPORT;
3581 }
3582
3583 /* In the normal, non-wrapper case, add a standard message to each deferred
3584 address if there hasn't been an error, that is, if it hasn't actually been
3585 tried this time. The variable "expired" will be FALSE if any deliveries were
3586 actually tried, or if there was at least one host that was not expired. That
3587 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
3588 a delivery has been tried, an error code will be set, and the failing of the
3589 message is handled by the retry code later.
3590
3591 If queue_smtp is set, or this transport was called to send a subsequent message
3592 down an existing TCP/IP connection, and something caused the host not to be
3593 found, we end up here, but can detect these cases and handle them specially. */
3594
3595 for (addr = addrlist; addr != NULL; addr = addr->next)
3596 {
3597 /* If host is not NULL, it means that we stopped processing the host list
3598 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
3599 means we need to behave as if some hosts were skipped because their retry
3600 time had not come. Specifically, this prevents the address from timing out.
3601 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
3602 hosts were tried. */
3603
3604 if (host != NULL)
3605 {
3606 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
3607 {
3608 DEBUG(D_transport)
3609 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
3610 "hosts were tried\n");
3611 }
3612 else
3613 {
3614 DEBUG(D_transport)
3615 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
3616 setflag(addr, af_retry_skipped);
3617 }
3618 }
3619
3620 if (queue_smtp) /* no deliveries attempted */
3621 {
3622 addr->transport_return = DEFER;
3623 addr->basic_errno = 0;
3624 addr->message = US"SMTP delivery explicitly queued";
3625 }
3626
3627 else if (addr->transport_return == DEFER &&
3628 (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0) &&
3629 addr->message == NULL)
3630 {
3631 addr->basic_errno = ERRNO_HRETRY;
3632 if (continue_hostname != NULL)
3633 {
3634 addr->message = US"no host found for existing SMTP connection";
3635 }
3636 else if (expired)
3637 {
3638 setflag(addr, af_pass_message); /* This is not a security risk */
3639 addr->message = (ob->delay_after_cutoff)?
3640 US"retry time not reached for any host after a long failure period" :
3641 US"all hosts have been failing for a long time and were last tried "
3642 "after this message arrived";
3643
3644 /* If we are already using fallback hosts, or there are no fallback hosts
3645 defined, convert the result to FAIL to cause a bounce. */
3646
3647 if (addr->host_list == addr->fallback_hosts ||
3648 addr->fallback_hosts == NULL)
3649 addr->transport_return = FAIL;
3650 }
3651 else
3652 {
3653 if (hosts_retry == hosts_total)
3654 addr->message = US"retry time not reached for any host";
3655 else if (hosts_fail == hosts_total)
3656 addr->message = US"all host address lookups failed permanently";
3657 else if (hosts_defer == hosts_total)
3658 addr->message = US"all host address lookups failed temporarily";
3659 else if (hosts_serial == hosts_total)
3660 addr->message = US"connection limit reached for all hosts";
3661 else if (hosts_fail+hosts_defer == hosts_total)
3662 addr->message = US"all host address lookups failed";
3663 else addr->message = US"some host address lookups failed and retry time "
3664 "not reached for other hosts or connection limit reached";
3665 }
3666 }
3667 }
3668
3669 /* Update the database which keeps information about which messages are waiting
3670 for which hosts to become available. For some message-specific errors, the
3671 update_waiting flag is turned off because we don't want follow-on deliveries in
3672 those cases. If this transport instance is explicitly limited to one message
3673 per connection then follow-on deliveries are not possible and there's no need
3674 to create/update the per-transport wait-<transport_name> database. */
3675
3676 if (update_waiting && tblock->connection_max_messages != 1)
3677 transport_update_waiting(hostlist, tblock->name);
3678
3679 END_TRANSPORT:
3680
3681 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3682
3683 return TRUE; /* Each address has its status */
3684 }
3685
3686 /* vi: aw ai sw=2
3687 */
3688 /* End of transport/smtp.c */
Unnamed repository; edit this file 'description' to name the repository.