1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2014 */
6 /* See the file NOTICE for conditions of use and distribution. */
12 #define PENDING_DEFER (PENDING + DEFER)
13 #define PENDING_OK (PENDING + OK)
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. */
21 optionlist smtp_transport_options[] = {
22 { "*expand_multi_domain", opt_stringptr | opt_hidden | opt_public,
23 (void *)offsetof(transport_instance, expand_multi_domain) },
24 { "*expand_retry_include_ip_address", opt_stringptr | opt_hidden,
25 (void *)(offsetof(smtp_transport_options_block, expand_retry_include_ip_address)) },
27 { "address_retry_include_sender", opt_bool,
28 (void *)offsetof(smtp_transport_options_block, address_retry_include_sender) },
29 { "allow_localhost", opt_bool,
30 (void *)offsetof(smtp_transport_options_block, allow_localhost) },
31 { "authenticated_sender", opt_stringptr,
32 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
33 { "authenticated_sender_force", opt_bool,
34 (void *)offsetof(smtp_transport_options_block, authenticated_sender_force) },
35 { "command_timeout", opt_time,
36 (void *)offsetof(smtp_transport_options_block, command_timeout) },
37 { "connect_timeout", opt_time,
38 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
39 { "connection_max_messages", opt_int | opt_public,
40 (void *)offsetof(transport_instance, connection_max_messages) },
41 { "data_timeout", opt_time,
42 (void *)offsetof(smtp_transport_options_block, data_timeout) },
43 { "delay_after_cutoff", opt_bool,
44 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
46 { "dkim_canon", opt_stringptr,
47 (void *)offsetof(smtp_transport_options_block, dkim_canon) },
48 { "dkim_domain", opt_stringptr,
49 (void *)offsetof(smtp_transport_options_block, dkim_domain) },
50 { "dkim_private_key", opt_stringptr,
51 (void *)offsetof(smtp_transport_options_block, dkim_private_key) },
52 { "dkim_selector", opt_stringptr,
53 (void *)offsetof(smtp_transport_options_block, dkim_selector) },
54 { "dkim_sign_headers", opt_stringptr,
55 (void *)offsetof(smtp_transport_options_block, dkim_sign_headers) },
56 { "dkim_strict", opt_stringptr,
57 (void *)offsetof(smtp_transport_options_block, dkim_strict) },
59 { "dns_qualify_single", opt_bool,
60 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
61 { "dns_search_parents", opt_bool,
62 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
63 { "dnssec_request_domains", opt_stringptr,
64 (void *)offsetof(smtp_transport_options_block, dnssec_request_domains) },
65 { "dnssec_require_domains", opt_stringptr,
66 (void *)offsetof(smtp_transport_options_block, dnssec_require_domains) },
67 { "dscp", opt_stringptr,
68 (void *)offsetof(smtp_transport_options_block, dscp) },
69 { "fallback_hosts", opt_stringptr,
70 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
71 { "final_timeout", opt_time,
72 (void *)offsetof(smtp_transport_options_block, final_timeout) },
73 { "gethostbyname", opt_bool,
74 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
76 /* These are no longer honoured, as of Exim 4.80; for now, we silently
77 ignore; 4.83 will warn, and a later-still release will remove
78 these options, so that using them becomes an error. */
79 { "gnutls_require_kx", opt_stringptr,
80 (void *)offsetof(smtp_transport_options_block, gnutls_require_kx) },
81 { "gnutls_require_mac", opt_stringptr,
82 (void *)offsetof(smtp_transport_options_block, gnutls_require_mac) },
83 { "gnutls_require_protocols", opt_stringptr,
84 (void *)offsetof(smtp_transport_options_block, gnutls_require_proto) },
86 { "helo_data", opt_stringptr,
87 (void *)offsetof(smtp_transport_options_block, helo_data) },
88 { "hosts", opt_stringptr,
89 (void *)offsetof(smtp_transport_options_block, hosts) },
90 { "hosts_avoid_esmtp", opt_stringptr,
91 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
92 { "hosts_avoid_pipelining", opt_stringptr,
93 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
95 { "hosts_avoid_tls", opt_stringptr,
96 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
98 { "hosts_max_try", opt_int,
99 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
100 { "hosts_max_try_hardlimit", opt_int,
101 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
103 { "hosts_nopass_tls", opt_stringptr,
104 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
106 { "hosts_override", opt_bool,
107 (void *)offsetof(smtp_transport_options_block, hosts_override) },
108 { "hosts_randomize", opt_bool,
109 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
110 #if defined(SUPPORT_TLS) && !defined(DISABLE_OCSP)
111 { "hosts_request_ocsp", opt_stringptr,
112 (void *)offsetof(smtp_transport_options_block, hosts_request_ocsp) },
114 { "hosts_require_auth", opt_stringptr,
115 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
117 # ifdef EXPERIMENTAL_DANE
118 { "hosts_require_dane", opt_stringptr,
119 (void *)offsetof(smtp_transport_options_block, hosts_require_dane) },
121 # ifndef DISABLE_OCSP
122 { "hosts_require_ocsp", opt_stringptr,
123 (void *)offsetof(smtp_transport_options_block, hosts_require_ocsp) },
125 { "hosts_require_tls", opt_stringptr,
126 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
128 { "hosts_try_auth", opt_stringptr,
129 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
130 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
131 { "hosts_try_dane", opt_stringptr,
132 (void *)offsetof(smtp_transport_options_block, hosts_try_dane) },
135 { "hosts_try_prdr", opt_stringptr,
136 (void *)offsetof(smtp_transport_options_block, hosts_try_prdr) },
139 { "hosts_verify_avoid_tls", opt_stringptr,
140 (void *)offsetof(smtp_transport_options_block, hosts_verify_avoid_tls) },
142 { "interface", opt_stringptr,
143 (void *)offsetof(smtp_transport_options_block, interface) },
144 { "keepalive", opt_bool,
145 (void *)offsetof(smtp_transport_options_block, keepalive) },
146 { "lmtp_ignore_quota", opt_bool,
147 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
148 { "max_rcpt", opt_int | opt_public,
149 (void *)offsetof(transport_instance, max_addresses) },
150 { "multi_domain", opt_expand_bool | opt_public,
151 (void *)offsetof(transport_instance, multi_domain) },
152 { "port", opt_stringptr,
153 (void *)offsetof(smtp_transport_options_block, port) },
154 { "protocol", opt_stringptr,
155 (void *)offsetof(smtp_transport_options_block, protocol) },
156 { "retry_include_ip_address", opt_expand_bool,
157 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
158 { "serialize_hosts", opt_stringptr,
159 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
160 { "size_addition", opt_int,
161 (void *)offsetof(smtp_transport_options_block, size_addition) }
163 ,{ "tls_certificate", opt_stringptr,
164 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
165 { "tls_crl", opt_stringptr,
166 (void *)offsetof(smtp_transport_options_block, tls_crl) },
167 { "tls_dh_min_bits", opt_int,
168 (void *)offsetof(smtp_transport_options_block, tls_dh_min_bits) },
169 { "tls_privatekey", opt_stringptr,
170 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
171 { "tls_require_ciphers", opt_stringptr,
172 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
173 { "tls_sni", opt_stringptr,
174 (void *)offsetof(smtp_transport_options_block, tls_sni) },
175 { "tls_tempfail_tryclear", opt_bool,
176 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
177 { "tls_try_verify_hosts", opt_stringptr,
178 (void *)offsetof(smtp_transport_options_block, tls_try_verify_hosts) },
179 { "tls_verify_cert_hostnames", opt_stringptr,
180 (void *)offsetof(smtp_transport_options_block,tls_verify_cert_hostnames)},
181 { "tls_verify_certificates", opt_stringptr,
182 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) },
183 { "tls_verify_hosts", opt_stringptr,
184 (void *)offsetof(smtp_transport_options_block, tls_verify_hosts) }
188 /* Size of the options list. An extern variable has to be used so that its
189 address can appear in the tables drtables.c. */
191 int smtp_transport_options_count =
192 sizeof(smtp_transport_options)/sizeof(optionlist);
194 /* Default private options block for the smtp transport. */
196 smtp_transport_options_block smtp_transport_option_defaults = {
198 NULL, /* fallback_hosts */
200 NULL, /* fallback_hostlist */
201 NULL, /* authenticated_sender */
202 US"$primary_hostname", /* helo_data */
203 NULL, /* interface */
205 US"smtp", /* protocol */
207 NULL, /* serialize_hosts */
208 NULL, /* hosts_try_auth */
209 NULL, /* hosts_require_auth */
210 #ifdef EXPERIMENTAL_DANE
211 NULL, /* hosts_try_dane */
212 NULL, /* hosts_require_dane */
215 US"*", /* hosts_try_prdr */
218 US"*", /* hosts_request_ocsp (except under DANE; tls_client_start()) */
219 NULL, /* hosts_require_ocsp */
221 NULL, /* hosts_require_tls */
222 NULL, /* hosts_avoid_tls */
223 US"*", /* hosts_verify_avoid_tls */
224 NULL, /* hosts_avoid_pipelining */
225 NULL, /* hosts_avoid_esmtp */
226 NULL, /* hosts_nopass_tls */
227 5*60, /* command_timeout */
228 5*60, /* connect_timeout; shorter system default overrides */
229 5*60, /* data timeout */
230 10*60, /* final timeout */
231 1024, /* size_addition */
232 5, /* hosts_max_try */
233 50, /* hosts_max_try_hardlimit */
234 TRUE, /* address_retry_include_sender */
235 FALSE, /* allow_localhost */
236 FALSE, /* authenticated_sender_force */
237 FALSE, /* gethostbyname */
238 TRUE, /* dns_qualify_single */
239 FALSE, /* dns_search_parents */
240 NULL, /* dnssec_request_domains */
241 NULL, /* dnssec_require_domains */
242 TRUE, /* delay_after_cutoff */
243 FALSE, /* hosts_override */
244 FALSE, /* hosts_randomize */
245 TRUE, /* keepalive */
246 FALSE, /* lmtp_ignore_quota */
247 NULL, /* expand_retry_include_ip_address */
248 TRUE /* retry_include_ip_address */
250 ,NULL, /* tls_certificate */
252 NULL, /* tls_privatekey */
253 NULL, /* tls_require_ciphers */
254 NULL, /* gnutls_require_kx */
255 NULL, /* gnutls_require_mac */
256 NULL, /* gnutls_require_proto */
258 US"system", /* tls_verify_certificates */
259 EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
260 /* tls_dh_min_bits */
261 TRUE, /* tls_tempfail_tryclear */
262 NULL, /* tls_verify_hosts */
263 US"*", /* tls_try_verify_hosts */
264 US"*" /* tls_verify_cert_hostnames */
267 ,NULL, /* dkim_canon */
268 NULL, /* dkim_domain */
269 NULL, /* dkim_private_key */
270 NULL, /* dkim_selector */
271 NULL, /* dkim_sign_headers */
272 NULL /* dkim_strict */
276 #ifdef EXPERIMENTAL_DSN
277 /* some DSN flags for use later */
279 static int rf_list[] = {rf_notify_never, rf_notify_success,
280 rf_notify_failure, rf_notify_delay };
282 static uschar *rf_names[] = { US"NEVER", US"SUCCESS", US"FAILURE", US"DELAY" };
289 static uschar *smtp_command; /* Points to last cmd for error messages */
290 static uschar *mail_command; /* Points to MAIL cmd for error messages */
291 static BOOL update_waiting; /* TRUE to update the "wait" database */
294 /*************************************************
295 * Setup entry point *
296 *************************************************/
298 /* This function is called when the transport is about to be used,
299 but before running it in a sub-process. It is used for two things:
301 (1) To set the fallback host list in addresses, when delivering.
302 (2) To pass back the interface, port, protocol, and other options, for use
303 during callout verification.
306 tblock pointer to the transport instance block
307 addrlist list of addresses about to be transported
308 tf if not NULL, pointer to block in which to return options
309 uid the uid that will be set (not used)
310 gid the gid that will be set (not used)
311 errmsg place for error message (not used)
313 Returns: OK always (FAIL, DEFER not used)
317 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
318 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
320 smtp_transport_options_block *ob =
321 (smtp_transport_options_block *)(tblock->options_block);
323 errmsg = errmsg; /* Keep picky compilers happy */
327 /* Pass back options if required. This interface is getting very messy. */
331 tf->interface = ob->interface;
333 tf->protocol = ob->protocol;
334 tf->hosts = ob->hosts;
335 tf->hosts_override = ob->hosts_override;
336 tf->hosts_randomize = ob->hosts_randomize;
337 tf->gethostbyname = ob->gethostbyname;
338 tf->qualify_single = ob->dns_qualify_single;
339 tf->search_parents = ob->dns_search_parents;
340 tf->helo_data = ob->helo_data;
343 /* Set the fallback host list for all the addresses that don't have fallback
344 host lists, provided that the local host wasn't present in the original host
347 if (!testflag(addrlist, af_local_host_removed))
349 for (; addrlist != NULL; addrlist = addrlist->next)
350 if (addrlist->fallback_hosts == NULL)
351 addrlist->fallback_hosts = ob->fallback_hostlist;
359 /*************************************************
360 * Initialization entry point *
361 *************************************************/
363 /* Called for each instance, after its options have been read, to
364 enable consistency checks to be done, or anything else that needs
367 Argument: pointer to the transport instance block
372 smtp_transport_init(transport_instance *tblock)
374 smtp_transport_options_block *ob =
375 (smtp_transport_options_block *)(tblock->options_block);
377 /* Retry_use_local_part defaults FALSE if unset */
379 if (tblock->retry_use_local_part == TRUE_UNSET)
380 tblock->retry_use_local_part = FALSE;
382 /* Set the default port according to the protocol */
384 if (ob->port == NULL)
385 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
386 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
388 /* Set up the setup entry point, to be called before subprocesses for this
391 tblock->setup = smtp_transport_setup;
393 /* Complain if any of the timeouts are zero. */
395 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
396 ob->final_timeout <= 0)
397 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
398 "command, data, or final timeout value is zero for %s transport",
401 /* If hosts_override is set and there are local hosts, set the global
402 flag that stops verify from showing router hosts. */
404 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
406 /* If there are any fallback hosts listed, build a chain of host items
407 for them, but do not do any lookups at this time. */
409 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
412 if ( ob->gnutls_require_kx
413 || ob->gnutls_require_mac
414 || ob->gnutls_require_proto)
415 log_write(0, LOG_MAIN, "WARNING: smtp transport options"
416 " gnutls_require_kx, gnutls_require_mac and gnutls_require_protocols"
425 /*************************************************
426 * Set delivery info into all active addresses *
427 *************************************************/
429 /* Only addresses whose status is >= PENDING are relevant. A lesser
430 status means that an address is not currently being processed.
433 addrlist points to a chain of addresses
434 errno_value to put in each address's errno field
435 msg to put in each address's message field
436 rc to put in each address's transport_return field
437 pass_message if TRUE, set the "pass message" flag in the address
438 host if set, mark addrs as having used this host
440 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
441 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
442 this particular type of timeout.
448 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
449 BOOL pass_message, host_item * host)
453 if (errno_value == ERRNO_CONNECTTIMEOUT)
455 errno_value = ETIMEDOUT;
456 orvalue = RTEF_CTOUT;
458 for (addr = addrlist; addr != NULL; addr = addr->next)
460 if (addr->transport_return < PENDING) continue;
461 addr->basic_errno = errno_value;
462 addr->more_errno |= orvalue;
466 if (pass_message) setflag(addr, af_pass_message);
468 addr->transport_return = rc;
470 addr->host_used = host;
476 /*************************************************
477 * Check an SMTP response *
478 *************************************************/
480 /* This function is given an errno code and the SMTP response buffer
481 to analyse, together with the host identification for generating messages. It
482 sets an appropriate message and puts the first digit of the response code into
483 the yield variable. If no response was actually read, a suitable digit is
487 host the current host, to get its name for messages
488 errno_value pointer to the errno value
489 more_errno from the top address for use with ERRNO_FILTER_FAIL
490 buffer the SMTP response buffer
491 yield where to put a one-digit SMTP response code
492 message where to put an errror message
493 pass_message set TRUE if message is an SMTP response
495 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
499 check_response(host_item *host, int *errno_value, int more_errno,
500 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
504 if (smtp_use_pipelining &&
505 (Ustrcmp(smtp_command, "MAIL") == 0 ||
506 Ustrcmp(smtp_command, "RCPT") == 0 ||
507 Ustrcmp(smtp_command, "DATA") == 0))
510 *yield = '4'; /* Default setting is to give a temporary error */
512 /* Handle response timeout */
514 if (*errno_value == ETIMEDOUT)
516 *message = US string_sprintf("SMTP timeout after %s%s",
518 if (transport_count > 0)
519 *message = US string_sprintf("%s (%d bytes written)", *message,
524 /* Handle malformed SMTP response */
526 if (*errno_value == ERRNO_SMTPFORMAT)
528 uschar *malfresp = string_printing(buffer);
529 while (isspace(*malfresp)) malfresp++;
530 *message = *malfresp == 0
531 ? string_sprintf("Malformed SMTP reply (an empty line) "
532 "in response to %s%s", pl, smtp_command)
533 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
534 pl, smtp_command, malfresp);
538 /* Handle a failed filter process error; can't send QUIT as we mustn't
541 if (*errno_value == ERRNO_FILTER_FAIL)
543 *message = US string_sprintf("transport filter process failed (%d)%s",
545 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
549 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
552 if (*errno_value == ERRNO_CHHEADER_FAIL)
555 US string_sprintf("failed to expand headers_add or headers_remove: %s",
556 expand_string_message);
560 /* Handle failure to write a complete data block */
562 if (*errno_value == ERRNO_WRITEINCOMPLETE)
564 *message = US string_sprintf("failed to write a data block");
568 /* Handle error responses from the remote mailer. */
572 uschar *s = string_printing(buffer);
573 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
574 "%s", pl, smtp_command, s);
575 *pass_message = TRUE;
580 /* No data was read. If there is no errno, this must be the EOF (i.e.
581 connection closed) case, which causes deferral. An explicit connection reset
582 error has the same effect. Otherwise, put the host's identity in the message,
583 leaving the errno value to be interpreted as well. In all cases, we have to
584 assume the connection is now dead. */
586 if (*errno_value == 0 || *errno_value == ECONNRESET)
588 *errno_value = ERRNO_SMTPCLOSED;
589 *message = US string_sprintf("Remote host closed connection "
590 "in response to %s%s", pl, smtp_command);
592 else *message = US string_sprintf("%s [%s]", host->name, host->address);
599 /*************************************************
600 * Write error message to logs *
601 *************************************************/
603 /* This writes to the main log and to the message log.
606 addr the address item containing error information
607 host the current host
613 write_logs(address_item *addr, host_item *host)
615 uschar * message = string_sprintf("H=%s [%s]", host->name, host->address);
619 message = string_sprintf("%s: %s", message, addr->message);
620 if (addr->basic_errno > 0)
621 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
622 log_write(0, LOG_MAIN, "%s", message);
623 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
627 if (log_extra_selector & LX_outgoing_port)
628 message = string_sprintf("%s:%d", message,
629 host->port == PORT_NONE ? 25 : host->port);
630 log_write(0, LOG_MAIN, "%s %s", message, strerror(addr->basic_errno));
631 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), message,
632 strerror(addr->basic_errno));
637 msglog_line(host_item * host, uschar * message)
639 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
640 host->name, host->address, message);
645 #ifdef EXPERIMENTAL_EVENT
646 /*************************************************
647 * Post-defer action *
648 *************************************************/
650 /* This expands an arbitrary per-transport string.
651 It might, for example, be used to write to the database log.
654 addr the address item containing error information
655 host the current host
661 deferred_event_raise(address_item *addr, host_item *host)
663 uschar * action = addr->transport->event_action;
664 uschar * save_domain;
670 save_domain = deliver_domain;
671 save_local = deliver_localpart;
673 /*XXX would ip & port already be set up? */
674 deliver_host_address = string_copy(host->address);
675 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
676 event_defer_errno = addr->basic_errno;
678 router_name = addr->router->name;
679 transport_name = addr->transport->name;
680 deliver_domain = addr->domain;
681 deliver_localpart = addr->local_part;
683 (void) event_raise(action, US"msg:host:defer",
685 ? addr->basic_errno > 0
686 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
687 : string_copy(addr->message)
688 : addr->basic_errno > 0
689 ? string_copy(US strerror(addr->basic_errno))
692 deliver_localpart = save_local;
693 deliver_domain = save_domain;
694 router_name = transport_name = NULL;
700 /*************************************************
701 * Synchronize SMTP responses *
702 *************************************************/
704 /* This function is called from smtp_deliver() to receive SMTP responses from
705 the server, and match them up with the commands to which they relate. When
706 PIPELINING is not in use, this function is called after every command, and is
707 therefore somewhat over-engineered, but it is simpler to use a single scheme
708 that works both with and without PIPELINING instead of having two separate sets
711 The set of commands that are buffered up with pipelining may start with MAIL
712 and may end with DATA; in between are RCPT commands that correspond to the
713 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
714 etc.) are never buffered.
716 Errors after MAIL or DATA abort the whole process leaving the response in the
717 buffer. After MAIL, pending responses are flushed, and the original command is
718 re-instated in big_buffer for error messages. For RCPT commands, the remote is
719 permitted to reject some recipient addresses while accepting others. However
720 certain errors clearly abort the whole process. Set the value in
721 transport_return to PENDING_OK if the address is accepted. If there is a
722 subsequent general error, it will get reset accordingly. If not, it will get
723 converted to OK at the end.
726 addrlist the complete address list
727 include_affixes TRUE if affixes include in RCPT
728 sync_addr ptr to the ptr of the one to start scanning at (updated)
729 host the host we are connected to
730 count the number of responses to read
732 include_sender true if 4xx retry is to include the sender it its key
733 pending_MAIL true if the first response is for MAIL
734 pending_DATA 0 if last command sent was not DATA
735 +1 if previously had a good recipient
736 -1 if not previously had a good recipient
737 inblock incoming SMTP block
738 timeout timeout value
739 buffer buffer for reading response
740 buffsize size of buffer
742 Returns: 3 if at least one address had 2xx and one had 5xx
743 2 if at least one address had 5xx but none had 2xx
744 1 if at least one host had a 2xx response, but none had 5xx
745 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
746 -1 timeout while reading RCPT response
747 -2 I/O or other non-response error for RCPT
748 -3 DATA or MAIL failed - errno and buffer set
752 sync_responses(address_item *addrlist, BOOL include_affixes,
753 address_item **sync_addr, host_item *host, int count,
754 BOOL address_retry_include_sender, BOOL pending_MAIL,
755 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
758 address_item *addr = *sync_addr;
761 /* Handle the response for a MAIL command. On error, reinstate the original
762 command in big_buffer for error message use, and flush any further pending
763 responses before returning, except after I/O errors and timeouts. */
768 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
770 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
771 if (errno == 0 && buffer[0] != 0)
773 uschar flushbuffer[4096];
775 if (buffer[0] == '4')
777 save_errno = ERRNO_MAIL4XX;
778 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
782 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
784 && (errno != 0 || flushbuffer[0] == 0))
790 if (pending_DATA) count--; /* Number of RCPT responses to come */
791 while (count-- > 0) /* Mark any pending addrs with the host used */
793 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
794 addr->host_used = host;
801 if (pending_DATA) count--; /* Number of RCPT responses to come */
803 /* Read and handle the required number of RCPT responses, matching each one up
804 with an address by scanning for the next address whose status is PENDING_DEFER.
809 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
811 /* The address was accepted */
812 addr->host_used = host;
814 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
817 addr->transport_return = PENDING_OK;
819 /* If af_dr_retry_exists is set, there was a routing delay on this address;
820 ensure that any address-specific retry record is expunged. We do this both
821 for the basic key and for the version that also includes the sender. */
823 if (testflag(addr, af_dr_retry_exists))
825 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
827 retry_add_item(addr, altkey, rf_delete);
828 retry_add_item(addr, addr->address_retry_key, rf_delete);
832 /* Timeout while reading the response */
834 else if (errno == ETIMEDOUT)
836 int save_errno = errno;
837 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
838 transport_rcpt_address(addr, include_affixes));
839 set_errno(addrlist, save_errno, message, DEFER, FALSE, NULL);
840 retry_add_item(addr, addr->address_retry_key, 0);
841 update_waiting = FALSE;
845 /* Handle other errors in obtaining an SMTP response by returning -1. This
846 will cause all the addresses to be deferred. Restore the SMTP command in
847 big_buffer for which we are checking the response, so the error message
850 else if (errno != 0 || buffer[0] == 0)
852 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
853 transport_rcpt_address(addr, include_affixes));
857 /* Handle SMTP permanent and temporary response codes. */
862 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
863 "%s", transport_rcpt_address(addr, include_affixes),
864 string_printing(buffer));
865 setflag(addr, af_pass_message);
866 msglog_line(host, addr->message);
868 /* The response was 5xx */
870 if (buffer[0] == '5')
872 addr->transport_return = FAIL;
876 /* The response was 4xx */
880 addr->transport_return = DEFER;
881 addr->basic_errno = ERRNO_RCPT4XX;
882 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
884 /* Log temporary errors if there are more hosts to be tried.
885 If not, log this last one in the == line. */
888 log_write(0, LOG_MAIN, "H=%s [%s]: %s", host->name, host->address, addr->message);
890 /* Do not put this message on the list of those waiting for specific
891 hosts, as otherwise it is likely to be tried too often. */
893 update_waiting = FALSE;
895 /* Add a retry item for the address so that it doesn't get tried again
896 too soon. If address_retry_include_sender is true, add the sender address
899 if (address_retry_include_sender)
901 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
903 retry_add_item(addr, altkey, 0);
905 else retry_add_item(addr, addr->address_retry_key, 0);
908 } /* Loop for next RCPT response */
910 /* Update where to start at for the next block of responses, unless we
911 have already handled all the addresses. */
913 if (addr != NULL) *sync_addr = addr->next;
915 /* Handle a response to DATA. If we have not had any good recipients, either
916 previously or in this block, the response is ignored. */
918 if (pending_DATA != 0 &&
919 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
924 if (pending_DATA > 0 || (yield & 1) != 0)
926 if (errno == 0 && buffer[0] == '4')
928 errno = ERRNO_DATA4XX;
929 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
933 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
934 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
935 "is in use and there were no good recipients\n", msg);
938 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
939 present) received 3xx. If any RCPTs were handled and yielded anything other
940 than 4xx, yield will be set non-zero. */
947 /* Do the client side of smtp-level authentication */
950 buffer EHLO response from server (gets overwritten)
951 addrlist chain of potential addresses to deliver
952 host host to deliver to
954 ibp, obp comms channel control blocks
957 OK Success, or failed (but not required): global "smtp_authenticated" set
958 DEFER Failed authentication (and was required)
959 ERROR Internal problem
961 FAIL_SEND Failed communications - transmit
966 smtp_auth(uschar *buffer, unsigned bufsize, address_item *addrlist, host_item *host,
967 smtp_transport_options_block *ob, BOOL is_esmtp,
968 smtp_inblock *ibp, smtp_outblock *obp)
971 uschar *fail_reason = US"server did not advertise AUTH support";
973 smtp_authenticated = FALSE;
974 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
975 require_auth = verify_check_given_host(&ob->hosts_require_auth, host);
977 if (is_esmtp && !regex_AUTH) regex_AUTH =
978 regex_must_compile(US"\\n250[\\s\\-]AUTH\\s+([\\-\\w\\s]+)(?:\\n|$)",
981 if (is_esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
983 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
984 expand_nmax = -1; /* reset */
986 /* Must not do this check until after we have saved the result of the
987 regex match above. */
989 if (require_auth == OK ||
990 verify_check_given_host(&ob->hosts_try_auth, host) == OK)
993 fail_reason = US"no common mechanisms were found";
995 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
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.
1003 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1007 (au->client_condition != NULL &&
1008 !expand_check_condition(au->client_condition, au->name,
1009 US"client authenticator")))
1011 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1013 (au->client)? "client_condition is false" :
1014 "not configured as a client");
1018 /* Loop to scan supported server mechanisms */
1023 int len = Ustrlen(au->public_name);
1024 while (isspace(*p)) p++;
1026 if (strncmpic(au->public_name, p, len) != 0 ||
1027 (p[len] != 0 && !isspace(p[len])))
1029 while (*p != 0 && !isspace(*p)) p++;
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. */
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",
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. */
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);
1059 /* Failure after writing a command */
1064 /* Failure after reading a response */
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);
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. */
1080 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1081 "authentication H=%s [%s] %s", au->name, host->name,
1082 host->address, buffer);
1085 /* Internal problem, message in buffer. */
1088 set_errno(addrlist, 0, string_copy(buffer), DEFER, FALSE, NULL);
1092 break; /* If not authenticated, try next authenticator */
1093 } /* Loop for scanning supported server mechanisms */
1094 } /* Loop for further authenticators */
1098 /* If we haven't authenticated, but are required to, give up. */
1100 if (require_auth == OK && !smtp_authenticated)
1102 set_errno(addrlist, ERRNO_AUTHFAIL,
1103 string_sprintf("authentication required but %s", fail_reason), DEFER,
1112 /* Construct AUTH appendix string for MAIL TO */
1115 buffer to build string
1116 addrlist chain of potential addresses to deliver
1117 ob transport options
1119 Globals smtp_authenticated
1120 client_authenticated_sender
1121 Return True on error, otherwise buffer has (possibly empty) terminated string
1125 smtp_mail_auth_str(uschar *buffer, unsigned bufsize, address_item *addrlist,
1126 smtp_transport_options_block *ob)
1128 uschar *local_authenticated_sender = authenticated_sender;
1131 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n", authenticated_sender, ob->authenticated_sender, smtp_authenticated?"Y":"N");
1134 if (ob->authenticated_sender != NULL)
1136 uschar *new = expand_string(ob->authenticated_sender);
1139 if (!expand_string_forcedfail)
1141 uschar *message = string_sprintf("failed to expand "
1142 "authenticated_sender: %s", expand_string_message);
1143 set_errno(addrlist, 0, message, DEFER, FALSE, NULL);
1147 else if (new[0] != 0) local_authenticated_sender = new;
1150 /* Add the authenticated sender address if present */
1152 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1153 local_authenticated_sender != NULL)
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);
1168 #ifdef EXPERIMENTAL_DANE
1170 tlsa_lookup(host_item * host, dns_answer * dnsa,
1171 BOOL dane_required, BOOL * dane)
1173 /* move this out to host.c given the similarity to dns_lookup() ? */
1175 uschar * fullname = buffer;
1177 /* TLSA lookup string */
1178 (void)sprintf(CS buffer, "_%d._tcp.%.256s", host->port, host->name);
1180 switch (dns_lookup(dnsa, buffer, T_TLSA, &fullname))
1183 return DEFER; /* just defer this TLS'd conn */
1189 log_write(0, LOG_MAIN, "DANE error: TLSA lookup failed");
1195 if (!dns_is_secure(dnsa))
1197 log_write(0, LOG_MAIN, "DANE error: TLSA lookup not DNSSEC");
1208 /*************************************************
1209 * Deliver address list to given host *
1210 *************************************************/
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.
1217 Otherwise, we have to make a connection to the remote host, and do the
1218 initial protocol exchange.
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.
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
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
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)
1260 address_item *sync_addr;
1261 address_item *first_addr = addrlist;
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;
1272 BOOL send_rset = TRUE;
1273 BOOL send_quit = TRUE;
1274 BOOL setting_up = TRUE;
1275 BOOL completed_address = FALSE;
1278 BOOL pass_message = FALSE;
1279 #ifndef DISABLE_PRDR
1280 BOOL prdr_offered = FALSE;
1283 #ifdef EXPERIMENTAL_DSN
1284 BOOL dsn_all_lasthop = TRUE;
1286 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1288 dns_answer tlsa_dnsa;
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];
1298 uschar buffer[4096];
1299 uschar inbuffer[4096];
1300 uschar outbuffer[4096];
1302 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
1304 *message_defer = FALSE;
1305 smtp_command = US"initial connection";
1306 if (max_rcpt == 0) max_rcpt = 999999;
1308 /* Set up the buffer for reading SMTP response packets. */
1310 inblock.buffer = inbuffer;
1311 inblock.buffersize = sizeof(inbuffer);
1312 inblock.ptr = inbuffer;
1313 inblock.ptrend = inbuffer;
1315 /* Set up the buffer for holding SMTP commands while pipelining */
1317 outblock.buffer = outbuffer;
1318 outblock.buffersize = sizeof(outbuffer);
1319 outblock.ptr = outbuffer;
1320 outblock.cmd_count = 0;
1321 outblock.authenticating = FALSE;
1323 /* Reset the parameters of a TLS session. */
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)
1333 tls_out.ocsp = OCSP_NOT_REQ;
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. */
1339 tls_modify_variables(&tls_out);
1344 set_errno(addrlist, 0, US"TLS support not available", DEFER, FALSE, NULL);
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. */
1353 if (continue_hostname == NULL)
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
1364 if (inblock.sock < 0)
1366 set_errno(addrlist, (errno == ETIMEDOUT)? ERRNO_CONNECTTIMEOUT : errno,
1367 NULL, DEFER, FALSE, NULL);
1371 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1375 tls_out.dane_verified = FALSE;
1376 tls_out.tlsa_usage = 0;
1378 dane_required = verify_check_given_host(&ob->hosts_require_dane, host) == OK;
1380 if (host->dnssec == DS_YES)
1383 || verify_check_given_host(&ob->hosts_try_dane, host) == OK
1385 if ((rc = tlsa_lookup(host, &tlsa_dnsa, dane_required, &dane)) != OK)
1388 else if (dane_required)
1390 log_write(0, LOG_MAIN, "DANE error: %s lookup not DNSSEC", host->name);
1395 ob->tls_tempfail_tryclear = FALSE;
1399 /* Expand the greeting message while waiting for the initial response. (Makes
1400 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1401 delayed till here so that $sending_interface and $sending_port are set. */
1403 helo_data = expand_string(ob->helo_data);
1405 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1406 is nevertheless a reasonably clean way of programming this kind of logic,
1407 where you want to escape on any error. */
1411 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1412 ob->command_timeout)) goto RESPONSE_FAILED;
1414 #ifdef EXPERIMENTAL_EVENT
1417 lookup_dnssec_authenticated = host->dnssec==DS_YES ? US"yes"
1418 : host->dnssec==DS_NO ? US"no" : NULL;
1419 s = event_raise(tblock->event_action, US"smtp:connect", buffer);
1422 set_errno(addrlist, 0,
1423 string_sprintf("deferred by smtp:connect event expansion: %s", s),
1424 DEFER, FALSE, NULL);
1431 /* Now check if the helo_data expansion went well, and sign off cleanly if
1434 if (helo_data == NULL)
1436 uschar *message = string_sprintf("failed to expand helo_data: %s",
1437 expand_string_message);
1438 set_errno(addrlist, 0, message, DEFER, FALSE, NULL);
1444 /** Debugging without sending a message
1445 addrlist->transport_return = DEFER;
1449 /* Errors that occur after this point follow an SMTP command, which is
1450 left in big_buffer by smtp_write_command() for use in error messages. */
1452 smtp_command = big_buffer;
1454 /* Tell the remote who we are...
1456 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1457 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1458 greeting is of this form. The assumption was that the far end supports it
1459 properly... but experience shows that there are some that give 5xx responses,
1460 even though the banner includes "ESMTP" (there's a bloody-minded one that
1461 says "ESMTP not spoken here"). Cope with that case.
1463 September 2000: Time has passed, and it seems reasonable now to always send
1464 EHLO at the start. It is also convenient to make the change while installing
1467 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1468 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1469 would be no way to send out the mails, so there is now a host list
1470 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1471 PIPELINING problem as well. Maybe it can also be useful to cure other
1472 problems with broken servers.
1474 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1475 Then somebody tried it with a Microsoft mailer... It seems that all other
1476 mailers use upper case for some reason (the RFC is quite clear about case
1477 independence) so, for peace of mind, I gave in. */
1479 esmtp = verify_check_given_host(&ob->hosts_avoid_esmtp, host) != OK;
1481 /* Alas; be careful, since this goto is not an error-out, so conceivably
1482 we might set data between here and the target which we assume to exist
1483 and be usable. I can see this coming back to bite us. */
1488 suppress_tls = FALSE;
1489 ob->tls_tempfail_tryclear = FALSE;
1490 smtp_command = US"SSL-on-connect";
1497 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1498 lmtp? "LHLO" : "EHLO", helo_data) < 0)
1500 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1501 ob->command_timeout))
1503 if (errno != 0 || buffer[0] == 0 || lmtp) goto RESPONSE_FAILED;
1510 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1515 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1517 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1518 ob->command_timeout)) goto RESPONSE_FAILED;
1521 /* Set IGNOREQUOTA if the response to LHLO specifies support and the
1522 lmtp_ignore_quota option was set. */
1524 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1525 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1526 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1528 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1531 tls_offered = esmtp &&
1532 pcre_exec(regex_STARTTLS, NULL, CS buffer, Ustrlen(buffer), 0,
1533 PCRE_EOPT, NULL, 0) >= 0;
1536 #ifndef DISABLE_PRDR
1537 prdr_offered = esmtp
1538 && pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(buffer), 0,
1539 PCRE_EOPT, NULL, 0) >= 0
1540 && verify_check_given_host(&ob->hosts_try_prdr, host) == OK;
1543 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1547 /* For continuing deliveries down the same channel, the socket is the standard
1548 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1549 below). Set up the pointer to where subsequent commands will be left, for
1550 error messages. Note that smtp_use_size and smtp_use_pipelining will have been
1551 set from the command line if they were set in the process that passed the
1556 inblock.sock = outblock.sock = fileno(stdin);
1557 smtp_command = big_buffer;
1558 host->port = port; /* Record the port that was used */
1561 /* If TLS is available on this connection, whether continued or not, attempt to
1562 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1563 send another EHLO - the server may give a different answer in secure mode. We
1564 use a separate buffer for reading the response to STARTTLS so that if it is
1565 negative, the original EHLO data is available for subsequent analysis, should
1566 the client not be required to use TLS. If the response is bad, copy the buffer
1567 for error analysis. */
1572 && verify_check_given_host(&ob->hosts_avoid_tls, host) != OK)
1574 uschar buffer2[4096];
1575 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1578 /* If there is an I/O error, transmission of this message is deferred. If
1579 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1580 false, we also defer. However, if there is a temporary rejection of STARTTLS
1581 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1582 STARTTLS, we carry on. This means we will try to send the message in clear,
1583 unless the host is in hosts_require_tls (tested below). */
1585 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1586 ob->command_timeout))
1588 if (errno != 0 || buffer2[0] == 0 ||
1589 (buffer2[0] == '4' && !ob->tls_tempfail_tryclear))
1591 Ustrncpy(buffer, buffer2, sizeof(buffer));
1592 goto RESPONSE_FAILED;
1596 /* STARTTLS accepted: try to negotiate a TLS session. */
1601 int rc = tls_client_start(inblock.sock, host, addrlist, tblock
1602 # ifdef EXPERIMENTAL_DANE
1603 , dane ? &tlsa_dnsa : NULL
1607 /* TLS negotiation failed; give an error. From outside, this function may
1608 be called again to try in clear on a new connection, if the options permit
1609 it for this host. */
1613 save_errno = ERRNO_TLSFAILURE;
1614 message = US"failure while setting up TLS session";
1619 /* TLS session is set up */
1621 for (addr = addrlist; addr != NULL; addr = addr->next)
1622 if (addr->transport_return == PENDING_DEFER)
1624 addr->cipher = tls_out.cipher;
1625 addr->ourcert = tls_out.ourcert;
1626 addr->peercert = tls_out.peercert;
1627 addr->peerdn = tls_out.peerdn;
1628 addr->ocsp = tls_out.ocsp;
1633 /* if smtps, we'll have smtp_command set to something else; always safe to
1635 smtp_command = big_buffer;
1637 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1638 helo_data is null, we are dealing with a connection that was passed from
1639 another process, and so we won't have expanded helo_data above. We have to
1640 expand it here. $sending_ip_address and $sending_port are set up right at the
1641 start of the Exim process (in exim.c). */
1643 if (tls_out.active >= 0)
1646 if (helo_data == NULL)
1648 helo_data = expand_string(ob->helo_data);
1649 if (helo_data == NULL)
1651 uschar *message = string_sprintf("failed to expand helo_data: %s",
1652 expand_string_message);
1653 set_errno(addrlist, 0, message, DEFER, FALSE, NULL);
1659 /* For SMTPS we need to wait for the initial OK response. */
1662 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1663 ob->command_timeout)) goto RESPONSE_FAILED;
1667 greeting_cmd = "EHLO";
1670 greeting_cmd = "HELO";
1672 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1675 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1676 lmtp? "LHLO" : greeting_cmd, helo_data) < 0)
1678 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1679 ob->command_timeout))
1680 goto RESPONSE_FAILED;
1683 /* If the host is required to use a secure channel, ensure that we
1687 # ifdef EXPERIMENTAL_DANE
1690 verify_check_given_host(&ob->hosts_require_tls, host) == OK
1693 save_errno = ERRNO_TLSREQUIRED;
1694 message = string_sprintf("a TLS session is required, but %s",
1695 tls_offered? "an attempt to start TLS failed" :
1696 "the server did not offer TLS support");
1699 #endif /*SUPPORT_TLS*/
1701 /* If TLS is active, we have just started it up and re-done the EHLO command,
1702 so its response needs to be analyzed. If TLS is not active and this is a
1703 continued session down a previously-used socket, we haven't just done EHLO, so
1706 if (continue_hostname == NULL
1708 || tls_out.active >= 0
1712 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
1713 lmtp_ignore_quota option was set. */
1715 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1716 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1717 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1719 /* If the response to EHLO specified support for the SIZE parameter, note
1720 this, provided size_addition is non-negative. */
1722 smtp_use_size = esmtp && ob->size_addition >= 0 &&
1723 pcre_exec(regex_SIZE, NULL, CS buffer, Ustrlen(CS buffer), 0,
1724 PCRE_EOPT, NULL, 0) >= 0;
1726 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
1727 the current host, esmtp will be false, so PIPELINING can never be used. If
1728 the current host matches hosts_avoid_pipelining, don't do it. */
1730 smtp_use_pipelining = esmtp
1731 && verify_check_given_host(&ob->hosts_avoid_pipelining, host) != OK
1732 && pcre_exec(regex_PIPELINING, NULL, CS buffer, Ustrlen(CS buffer), 0,
1733 PCRE_EOPT, NULL, 0) >= 0;
1735 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
1736 smtp_use_pipelining? "" : "not ");
1738 #ifndef DISABLE_PRDR
1739 prdr_offered = esmtp
1740 && pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(CS buffer), 0,
1741 PCRE_EOPT, NULL, 0) >= 0
1742 && verify_check_given_host(&ob->hosts_try_prdr, host) == OK;
1745 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1748 #ifdef EXPERIMENTAL_DSN
1749 /* Note if the server supports DSN */
1750 smtp_use_dsn = esmtp && pcre_exec(regex_DSN, NULL, CS buffer, (int)Ustrlen(CS buffer), 0,
1751 PCRE_EOPT, NULL, 0) >= 0;
1752 DEBUG(D_transport) debug_printf("use_dsn=%d\n", smtp_use_dsn);
1755 /* Note if the response to EHLO specifies support for the AUTH extension.
1756 If it has, check that this host is one we want to authenticate to, and do
1757 the business. The host name and address must be available when the
1758 authenticator's client driver is running. */
1760 switch (yield = smtp_auth(buffer, sizeof(buffer), addrlist, host,
1761 ob, esmtp, &inblock, &outblock))
1763 default: goto SEND_QUIT;
1765 case FAIL_SEND: goto SEND_FAILED;
1766 case FAIL: goto RESPONSE_FAILED;
1770 /* The setting up of the SMTP call is now complete. Any subsequent errors are
1771 message-specific. */
1775 /* If there is a filter command specified for this transport, we can now
1776 set it up. This cannot be done until the identify of the host is known. */
1778 if (tblock->filter_command != NULL)
1782 sprintf(CS buffer, "%.50s transport", tblock->name);
1783 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
1784 TRUE, DEFER, addrlist, buffer, NULL);
1785 transport_filter_timeout = tblock->filter_timeout;
1787 /* On failure, copy the error to all addresses, abandon the SMTP call, and
1792 set_errno(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
1800 /* For messages that have more than the maximum number of envelope recipients,
1801 we want to send several transactions down the same SMTP connection. (See
1802 comments in deliver.c as to how this reconciles, heuristically, with
1803 remote_max_parallel.) This optimization was added to Exim after the following
1804 code was already working. The simplest way to put it in without disturbing the
1805 code was to use a goto to jump back to this point when there is another
1806 transaction to handle. */
1809 sync_addr = first_addr;
1813 completed_address = FALSE;
1816 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
1817 qualification, send it, adding something to the message size to allow for
1818 imprecision and things that get added en route. Exim keeps the number of lines
1819 in a message, so we can give an accurate value for the original message, but we
1820 need some additional to handle added headers. (Double "." characters don't get
1821 included in the count.) */
1828 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
1832 #ifndef DISABLE_PRDR
1833 prdr_active = FALSE;
1836 for (addr = first_addr; addr; addr = addr->next)
1837 if (addr->transport_return == PENDING_DEFER)
1839 for (addr = addr->next; addr; addr = addr->next)
1840 if (addr->transport_return == PENDING_DEFER)
1841 { /* at least two recipients to send */
1843 sprintf(CS p, " PRDR"); p += 5;
1851 #ifdef EXPERIMENTAL_DSN
1852 /* check if all addresses have lasthop flag */
1853 /* do not send RET and ENVID if true */
1854 dsn_all_lasthop = TRUE;
1855 for (addr = first_addr;
1856 address_count < max_rcpt && addr != NULL;
1858 if ((addr->dsn_flags & rf_dsnlasthop) != 1)
1859 dsn_all_lasthop = FALSE;
1861 /* Add any DSN flags to the mail command */
1863 if ((smtp_use_dsn) && (dsn_all_lasthop == FALSE))
1865 if (dsn_ret == dsn_ret_hdrs)
1867 Ustrcpy(p, " RET=HDRS");
1870 else if (dsn_ret == dsn_ret_full)
1872 Ustrcpy(p, " RET=FULL");
1875 if (dsn_envid != NULL)
1877 string_format(p, sizeof(buffer) - (p-buffer), " ENVID=%s", dsn_envid);
1883 /* If an authenticated_sender override has been specified for this transport
1884 instance, expand it. If the expansion is forced to fail, and there was already
1885 an authenticated_sender for this message, the original value will be used.
1886 Other expansion failures are serious. An empty result is ignored, but there is
1887 otherwise no check - this feature is expected to be used with LMTP and other
1888 cases where non-standard addresses (e.g. without domains) might be required. */
1890 if (smtp_mail_auth_str(p, sizeof(buffer) - (p-buffer), addrlist, ob))
1896 /* From here until we send the DATA command, we can make use of PIPELINING
1897 if the server host supports it. The code has to be able to check the responses
1898 at any point, for when the buffer fills up, so we write it totally generally.
1899 When PIPELINING is off, each command written reports that it has flushed the
1902 pending_MAIL = TRUE; /* The block starts with MAIL */
1904 rc = smtp_write_command(&outblock, smtp_use_pipelining,
1905 "MAIL FROM:<%s>%s\r\n", return_path, buffer);
1906 mail_command = string_copy(big_buffer); /* Save for later error message */
1910 case -1: /* Transmission error */
1913 case +1: /* Block was sent */
1914 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1915 ob->command_timeout))
1917 if (errno == 0 && buffer[0] == '4')
1919 errno = ERRNO_MAIL4XX;
1920 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1922 goto RESPONSE_FAILED;
1924 pending_MAIL = FALSE;
1928 /* Pass over all the relevant recipient addresses for this host, which are the
1929 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
1930 several before we have to read the responses for those seen so far. This
1931 checking is done by a subroutine because it also needs to be done at the end.
1932 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
1933 the next one if not all are sent.
1935 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
1936 last address because we want to abort if any recipients have any kind of
1937 problem, temporary or permanent. We know that all recipient addresses will have
1938 the PENDING_DEFER status, because only one attempt is ever made, and we know
1939 that max_rcpt will be large, so all addresses will be done at once. */
1941 for (addr = first_addr;
1942 address_count < max_rcpt && addr != NULL;
1948 #ifdef EXPERIMENTAL_DSN
1949 addr->dsn_aware = smtp_use_dsn ? dsn_support_yes : dsn_support_no;
1952 if (addr->transport_return != PENDING_DEFER) continue;
1955 no_flush = smtp_use_pipelining && (!mua_wrapper || addr->next != NULL);
1957 #ifdef EXPERIMENTAL_DSN
1958 /* Add any DSN flags to the rcpt command and add to the sent string */
1963 if (smtp_use_dsn && (addr->dsn_flags & rf_dsnlasthop) != 1)
1965 if ((addr->dsn_flags & rf_dsnflags) != 0)
1969 Ustrcpy(p, " NOTIFY=");
1971 for (i = 0; i < 4; i++)
1972 if ((addr->dsn_flags & rf_list[i]) != 0)
1974 if (!first) *p++ = ',';
1976 Ustrcpy(p, rf_names[i]);
1981 if (addr->dsn_orcpt != NULL)
1983 string_format(p, sizeof(buffer) - (p-buffer), " ORCPT=%s",
1991 /* Now send the RCPT command, and process outstanding responses when
1992 necessary. After a timeout on RCPT, we just end the function, leaving the
1993 yield as OK, because this error can often mean that there is a problem with
1994 just one address, so we don't want to delay the host. */
1996 #ifdef EXPERIMENTAL_DSN
1997 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s%s\r\n",
1998 transport_rcpt_address(addr, tblock->rcpt_include_affixes), igquotstr, buffer);
2000 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s\r\n",
2001 transport_rcpt_address(addr, tblock->rcpt_include_affixes), igquotstr);
2004 if (count < 0) goto SEND_FAILED;
2007 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
2008 &sync_addr, host, count, ob->address_retry_include_sender,
2009 pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
2012 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2013 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2016 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2017 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2018 case 0: /* No 2xx or 5xx, but no probs */
2021 case -1: goto END_OFF; /* Timeout on RCPT */
2022 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
2024 pending_MAIL = FALSE; /* Dealt with MAIL */
2026 } /* Loop for next address */
2028 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
2029 permanently or temporarily. We should have flushed and synced after the last
2034 address_item *badaddr;
2035 for (badaddr = first_addr; badaddr != NULL; badaddr = badaddr->next)
2037 if (badaddr->transport_return != PENDING_OK) break;
2039 if (badaddr != NULL)
2041 set_errno(addrlist, 0, badaddr->message, FAIL,
2042 testflag(badaddr, af_pass_message), NULL);
2047 /* If ok is TRUE, we know we have got at least one good recipient, and must now
2048 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
2049 have a good recipient buffered up if we are pipelining. We don't want to waste
2050 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
2051 are pipelining. The responses are all handled by sync_responses(). */
2053 if (ok || (smtp_use_pipelining && !mua_wrapper))
2055 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
2056 if (count < 0) goto SEND_FAILED;
2057 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
2058 host, count, ob->address_retry_include_sender, pending_MAIL,
2059 ok? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
2061 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2062 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2065 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2066 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2067 case 0: break; /* No 2xx or 5xx, but no probs */
2069 case -1: goto END_OFF; /* Timeout on RCPT */
2070 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2074 /* Save the first address of the next batch. */
2078 /* If there were no good recipients (but otherwise there have been no
2079 problems), just set ok TRUE, since we have handled address-specific errors
2080 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
2081 for handling the SMTP dot-handling protocol, flagging to apply to headers as
2082 well as body. Set the appropriate timeout value to be used for each chunk.
2083 (Haven't been able to make it work using select() for writing yet.) */
2085 if (!ok) ok = TRUE; else
2087 sigalrm_seen = FALSE;
2088 transport_write_timeout = ob->data_timeout;
2089 smtp_command = US"sending data block"; /* For error messages */
2090 DEBUG(D_transport|D_v)
2091 debug_printf(" SMTP>> writing message and terminating \".\"\n");
2092 transport_count = 0;
2094 #ifndef DISABLE_DKIM
2095 ok = dkim_transport_write_message(addrlist, inblock.sock,
2096 topt_use_crlf | topt_end_dot | topt_escape_headers |
2097 (tblock->body_only? topt_no_headers : 0) |
2098 (tblock->headers_only? topt_no_body : 0) |
2099 (tblock->return_path_add? topt_add_return_path : 0) |
2100 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
2101 (tblock->envelope_to_add? topt_add_envelope_to : 0),
2102 0, /* No size limit */
2103 tblock->add_headers, tblock->remove_headers,
2104 US".", US"..", /* Escaping strings */
2105 tblock->rewrite_rules, tblock->rewrite_existflags,
2106 ob->dkim_private_key, ob->dkim_domain, ob->dkim_selector,
2107 ob->dkim_canon, ob->dkim_strict, ob->dkim_sign_headers
2110 ok = transport_write_message(addrlist, inblock.sock,
2111 topt_use_crlf | topt_end_dot | topt_escape_headers |
2112 (tblock->body_only? topt_no_headers : 0) |
2113 (tblock->headers_only? topt_no_body : 0) |
2114 (tblock->return_path_add? topt_add_return_path : 0) |
2115 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
2116 (tblock->envelope_to_add? topt_add_envelope_to : 0),
2117 0, /* No size limit */
2118 tblock->add_headers, tblock->remove_headers,
2119 US".", US"..", /* Escaping strings */
2120 tblock->rewrite_rules, tblock->rewrite_existflags);
2123 /* transport_write_message() uses write() because it is called from other
2124 places to write to non-sockets. This means that under some OS (e.g. Solaris)
2125 it can exit with "Broken pipe" as its error. This really means that the
2126 socket got closed at the far end. */
2128 transport_write_timeout = 0; /* for subsequent transports */
2130 /* Failure can either be some kind of I/O disaster (including timeout),
2131 or the failure of a transport filter or the expansion of added headers. */
2135 buffer[0] = 0; /* There hasn't been a response */
2136 goto RESPONSE_FAILED;
2139 /* We used to send the terminating "." explicitly here, but because of
2140 buffering effects at both ends of TCP/IP connections, you don't gain
2141 anything by keeping it separate, so it might as well go in the final
2142 data buffer for efficiency. This is now done by setting the topt_end_dot
2145 smtp_command = US"end of data";
2147 #ifndef DISABLE_PRDR
2148 /* For PRDR we optionally get a partial-responses warning
2149 * followed by the individual responses, before going on with
2150 * the overall response. If we don't get the warning then deal
2151 * with per non-PRDR. */
2154 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '3',
2156 if (!ok && errno == 0)
2159 case '2': prdr_active = FALSE;
2162 case '4': errno = ERRNO_DATA4XX;
2163 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2170 /* For non-PRDR SMTP, we now read a single response that applies to the
2171 whole message. If it is OK, then all the addresses have been delivered. */
2175 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2177 if (!ok && errno == 0 && buffer[0] == '4')
2179 errno = ERRNO_DATA4XX;
2180 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2184 /* For LMTP, we get back a response for every RCPT command that we sent;
2185 some may be accepted and some rejected. For those that get a response, their
2186 status is fixed; any that are accepted have been handed over, even if later
2187 responses crash - at least, that's how I read RFC 2033.
2189 If all went well, mark the recipient addresses as completed, record which
2190 host/IPaddress they were delivered to, and cut out RSET when sending another
2191 message down the same channel. Write the completed addresses to the journal
2192 now so that they are recorded in case there is a crash of hardware or
2193 software before the spool gets updated. Also record the final SMTP
2194 confirmation if needed (for SMTP only). */
2199 int delivery_time = (int)(time(NULL) - start_delivery_time);
2202 uschar *conf = NULL;
2205 /* Make a copy of the host if it is local to this invocation
2206 of the transport. */
2210 thost = store_get(sizeof(host_item));
2212 thost->name = string_copy(host->name);
2213 thost->address = string_copy(host->address);
2217 /* Set up confirmation if needed - applies only to SMTP */
2220 #ifndef EXPERIMENTAL_EVENT
2221 (log_extra_selector & LX_smtp_confirmation) != 0 &&
2226 uschar *s = string_printing(buffer);
2227 conf = (s == buffer)? (uschar *)string_copy(s) : s;
2230 /* Process all transported addresses - for LMTP or PRDR, read a status for
2233 for (addr = addrlist; addr != first_addr; addr = addr->next)
2235 if (addr->transport_return != PENDING_OK) continue;
2237 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
2238 remaining addresses. Otherwise, it's a return code for just the one
2239 address. For temporary errors, add a retry item for the address so that
2240 it doesn't get tried again too soon. */
2242 #ifndef DISABLE_PRDR
2243 if (lmtp || prdr_active)
2248 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2251 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
2252 addr->message = string_sprintf(
2253 #ifndef DISABLE_PRDR
2254 "%s error after %s: %s", prdr_active ? "PRDR":"LMTP",
2256 "LMTP error after %s: %s",
2258 big_buffer, string_printing(buffer));
2259 setflag(addr, af_pass_message); /* Allow message to go to user */
2260 if (buffer[0] == '5')
2261 addr->transport_return = FAIL;
2264 errno = ERRNO_DATA4XX;
2265 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2266 addr->transport_return = DEFER;
2267 #ifndef DISABLE_PRDR
2270 retry_add_item(addr, addr->address_retry_key, 0);
2274 completed_address = TRUE; /* NOW we can set this flag */
2275 if ((log_extra_selector & LX_smtp_confirmation) != 0)
2277 uschar *s = string_printing(buffer);
2278 conf = (s == buffer)? (uschar *)string_copy(s) : s;
2282 /* SMTP, or success return from LMTP for this address. Pass back the
2283 actual host that was used. */
2285 addr->transport_return = OK;
2286 addr->more_errno = delivery_time;
2287 addr->host_used = thost;
2288 addr->special_action = flag;
2289 addr->message = conf;
2290 #ifndef DISABLE_PRDR
2291 if (prdr_active) addr->flags |= af_prdr_used;
2295 #ifndef DISABLE_PRDR
2299 /* Update the journal. For homonymic addresses, use the base address plus
2300 the transport name. See lots of comments in deliver.c about the reasons
2301 for the complications when homonyms are involved. Just carry on after
2302 write error, as it may prove possible to update the spool file later. */
2304 if (testflag(addr, af_homonym))
2305 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2307 sprintf(CS buffer, "%.500s\n", addr->unique);
2309 DEBUG(D_deliver) debug_printf("journalling %s", buffer);
2310 len = Ustrlen(CS buffer);
2311 if (write(journal_fd, buffer, len) != len)
2312 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2313 "%s: %s", buffer, strerror(errno));
2317 #ifndef DISABLE_PRDR
2320 /* PRDR - get the final, overall response. For any non-success
2321 upgrade all the address statuses. */
2322 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2326 if(errno == 0 && buffer[0] == '4')
2328 errno = ERRNO_DATA4XX;
2329 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2331 for (addr = addrlist; addr != first_addr; addr = addr->next)
2332 if (buffer[0] == '5' || addr->transport_return == OK)
2333 addr->transport_return = PENDING_OK; /* allow set_errno action */
2334 goto RESPONSE_FAILED;
2337 /* Update the journal, or setup retry. */
2338 for (addr = addrlist; addr != first_addr; addr = addr->next)
2339 if (addr->transport_return == OK)
2341 if (testflag(addr, af_homonym))
2342 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2344 sprintf(CS buffer, "%.500s\n", addr->unique);
2346 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s", buffer);
2347 len = Ustrlen(CS buffer);
2348 if (write(journal_fd, buffer, len) != len)
2349 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2350 "%s: %s", buffer, strerror(errno));
2352 else if (addr->transport_return == DEFER)
2353 retry_add_item(addr, addr->address_retry_key, -2);
2357 /* Ensure the journal file is pushed out to disk. */
2359 if (EXIMfsync(journal_fd) < 0)
2360 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
2366 /* Handle general (not specific to one address) failures here. The value of ok
2367 is used to skip over this code on the falling through case. A timeout causes a
2368 deferral. Other errors may defer or fail according to the response code, and
2369 may set up a special errno value, e.g. after connection chopped, which is
2370 assumed if errno == 0 and there is no text in the buffer. If control reaches
2371 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
2372 the problem is not related to this specific message. */
2381 send_quit = check_response(host, &save_errno, addrlist->more_errno,
2382 buffer, &code, &message, &pass_message);
2388 message = US string_sprintf("send() to %s [%s] failed: %s",
2389 host->name, host->address, strerror(save_errno));
2393 /* This label is jumped to directly when a TLS negotiation has failed,
2394 or was not done for a host for which it is required. Values will be set
2395 in message and save_errno, and setting_up will always be true. Treat as
2396 a temporary error. */
2403 /* If the failure happened while setting up the call, see if the failure was
2404 a 5xx response (this will either be on connection, or following HELO - a 5xx
2405 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
2406 never going to accept them. For other errors during setting up (timeouts or
2407 whatever), defer all addresses, and yield DEFER, so that the host is not
2408 tried again for a while. */
2411 ok = FALSE; /* For when reached by GOTO */
2416 set_errno(addrlist, save_errno, message, FAIL, pass_message, host);
2419 set_errno(addrlist, save_errno, message, DEFER, pass_message, host);
2424 /* We want to handle timeouts after MAIL or "." and loss of connection after
2425 "." specially. They can indicate a problem with the sender address or with
2426 the contents of the message rather than a real error on the connection. These
2427 cases are treated in the same way as a 4xx response. This next bit of code
2428 does the classification. */
2439 message_error = TRUE;
2443 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
2444 Ustrncmp(smtp_command,"end ",4) == 0;
2447 case ERRNO_SMTPCLOSED:
2448 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
2452 message_error = FALSE;
2456 /* Handle the cases that are treated as message errors. These are:
2458 (a) negative response or timeout after MAIL
2459 (b) negative response after DATA
2460 (c) negative response or timeout or dropped connection after "."
2462 It won't be a negative response or timeout after RCPT, as that is dealt
2463 with separately above. The action in all cases is to set an appropriate
2464 error code for all the addresses, but to leave yield set to OK because the
2465 host itself has not failed. Of course, it might in practice have failed
2466 when we've had a timeout, but if so, we'll discover that at the next
2467 delivery attempt. For a temporary error, set the message_defer flag, and
2468 write to the logs for information if this is not the last host. The error
2469 for the last host will be logged as part of the address's log line. */
2473 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
2474 set_errno(addrlist, save_errno, message, (code == '5')? FAIL : DEFER,
2475 pass_message, host);
2477 /* If there's an errno, the message contains just the identity of
2480 if (code != '5') /* Anything other than 5 is treated as temporary */
2483 message = US string_sprintf("%s: %s", message, strerror(save_errno));
2484 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
2485 msglog_line(host, message);
2486 *message_defer = TRUE;
2490 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
2491 ".", or some other transportation error. We defer all addresses and yield
2492 DEFER, except for the case of failed add_headers expansion, or a transport
2493 filter failure, when the yield should be ERROR, to stop it trying other
2498 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
2499 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
2500 set_errno(addrlist, save_errno, message, DEFER, pass_message, host);
2506 /* If all has gone well, send_quit will be set TRUE, implying we can end the
2507 SMTP session tidily. However, if there were too many addresses to send in one
2508 message (indicated by first_addr being non-NULL) we want to carry on with the
2509 rest of them. Also, it is desirable to send more than one message down the SMTP
2510 connection if there are several waiting, provided we haven't already sent so
2511 many as to hit the configured limit. The function transport_check_waiting looks
2512 for a waiting message and returns its id. Then transport_pass_socket tries to
2513 set up a continued delivery by passing the socket on to another process. The
2514 variable send_rset is FALSE if a message has just been successfully transfered.
2516 If we are already sending down a continued channel, there may be further
2517 addresses not yet delivered that are aimed at the same host, but which have not
2518 been passed in this run of the transport. In this case, continue_more will be
2519 true, and all we should do is send RSET if necessary, and return, leaving the
2522 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
2523 do not want to continue with other messages down the same channel, because that
2524 can lead to looping between two or more messages, all with the same,
2525 temporarily failing address(es). [The retry information isn't updated yet, so
2526 new processes keep on trying.] We probably also don't want to try more of this
2527 message's addresses either.
2529 If we have started a TLS session, we have to end it before passing the
2530 connection to a new process. However, not all servers can handle this (Exim
2531 can), so we do not pass such a connection on if the host matches
2532 hosts_nopass_tls. */
2535 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
2536 "yield=%d first_address is %sNULL\n", ok, send_quit, send_rset,
2537 continue_more, yield, (first_addr == NULL)? "":"not ");
2539 if (completed_address && ok && send_quit)
2542 if ( first_addr != NULL
2544 || ( ( tls_out.active < 0
2545 || verify_check_given_host(&ob->hosts_nopass_tls, host) != OK
2548 transport_check_waiting(tblock->name, host->name,
2549 tblock->connection_max_messages, new_message_id, &more)
2557 if (! (ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
2559 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
2560 host->address, strerror(save_errno));
2563 else if (! (ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2564 ob->command_timeout)))
2567 send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
2571 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
2572 host->name, host->address, msg);
2577 /* Either RSET was not needed, or it succeeded */
2581 if (first_addr != NULL) /* More addresses still to be sent */
2582 { /* in this run of the transport */
2583 continue_sequence++; /* Causes * in logging */
2586 if (continue_more) return yield; /* More addresses for another run */
2588 /* Pass the socket to a new Exim process. Before doing so, we must shut
2589 down TLS. Not all MTAs allow for the continuation of the SMTP session
2590 when TLS is shut down. We test for this by sending a new EHLO. If we
2591 don't get a good response, we don't attempt to pass the socket on. */
2594 if (tls_out.active >= 0)
2596 tls_close(FALSE, TRUE);
2600 ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
2601 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2602 ob->command_timeout);
2606 /* If the socket is successfully passed, we musn't send QUIT (or
2607 indeed anything!) from here. */
2609 if (ok && transport_pass_socket(tblock->name, host->name, host->address,
2610 new_message_id, inblock.sock))
2616 /* If RSET failed and there are addresses left, they get deferred. */
2618 else set_errno(first_addr, errno, msg, DEFER, FALSE, host);
2622 /* End off tidily with QUIT unless the connection has died or the socket has
2623 been passed to another process. There has been discussion on the net about what
2624 to do after sending QUIT. The wording of the RFC suggests that it is necessary
2625 to wait for a response, but on the other hand, there isn't anything one can do
2626 with an error response, other than log it. Exim used to do that. However,
2627 further discussion suggested that it is positively advantageous not to wait for
2628 the response, but to close the session immediately. This is supposed to move
2629 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
2630 load from the server. (Hosts that are both servers and clients may not see much
2631 difference, of course.) Further discussion indicated that this was safe to do
2632 on Unix systems which have decent implementations of TCP/IP that leave the
2633 connection around for a while (TIME_WAIT) after the application has gone away.
2634 This enables the response sent by the server to be properly ACKed rather than
2635 timed out, as can happen on broken TCP/IP implementations on other OS.
2637 This change is being made on 31-Jul-98. After over a year of trouble-free
2638 operation, the old commented-out code was removed on 17-Sep-99. */
2641 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2646 tls_close(FALSE, TRUE);
2649 /* Close the socket, and return the appropriate value, first setting
2650 works because the NULL setting is passed back to the calling process, and
2651 remote_max_parallel is forced to 1 when delivering over an existing connection,
2653 If all went well and continue_more is set, we shouldn't actually get here if
2654 there are further addresses, as the return above will be taken. However,
2655 writing RSET might have failed, or there may be other addresses whose hosts are
2656 specified in the transports, and therefore not visible at top level, in which
2657 case continue_more won't get set. */
2659 (void)close(inblock.sock);
2661 #ifdef EXPERIMENTAL_EVENT
2662 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
2665 continue_transport = NULL;
2666 continue_hostname = NULL;
2673 /*************************************************
2674 * Closedown entry point *
2675 *************************************************/
2677 /* This function is called when exim is passed an open smtp channel
2678 from another incarnation, but the message which it has been asked
2679 to deliver no longer exists. The channel is on stdin.
2681 We might do fancy things like looking for another message to send down
2682 the channel, but if the one we sought has gone, it has probably been
2683 delivered by some other process that itself will seek further messages,
2684 so just close down our connection.
2686 Argument: pointer to the transport instance block
2691 smtp_transport_closedown(transport_instance *tblock)
2693 smtp_transport_options_block *ob =
2694 (smtp_transport_options_block *)(tblock->options_block);
2695 smtp_inblock inblock;
2696 smtp_outblock outblock;
2698 uschar inbuffer[4096];
2699 uschar outbuffer[16];
2701 inblock.sock = fileno(stdin);
2702 inblock.buffer = inbuffer;
2703 inblock.buffersize = sizeof(inbuffer);
2704 inblock.ptr = inbuffer;
2705 inblock.ptrend = inbuffer;
2707 outblock.sock = inblock.sock;
2708 outblock.buffersize = sizeof(outbuffer);
2709 outblock.buffer = outbuffer;
2710 outblock.ptr = outbuffer;
2711 outblock.cmd_count = 0;
2712 outblock.authenticating = FALSE;
2714 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2715 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2716 ob->command_timeout);
2717 (void)close(inblock.sock);
2722 /*************************************************
2723 * Prepare addresses for delivery *
2724 *************************************************/
2726 /* This function is called to flush out error settings from previous delivery
2727 attempts to other hosts. It also records whether we got here via an MX record
2728 or not in the more_errno field of the address. We are interested only in
2729 addresses that are still marked DEFER - others may have got delivered to a
2730 previously considered IP address. Set their status to PENDING_DEFER to indicate
2731 which ones are relevant this time.
2734 addrlist the list of addresses
2735 host the host we are delivering to
2737 Returns: the first address for this delivery
2740 static address_item *
2741 prepare_addresses(address_item *addrlist, host_item *host)
2743 address_item *first_addr = NULL;
2745 for (addr = addrlist; addr != NULL; addr = addr->next)
2747 if (addr->transport_return != DEFER) continue;
2748 if (first_addr == NULL) first_addr = addr;
2749 addr->transport_return = PENDING_DEFER;
2750 addr->basic_errno = 0;
2751 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
2752 addr->message = NULL;
2754 addr->cipher = NULL;
2755 addr->ourcert = NULL;
2756 addr->peercert = NULL;
2757 addr->peerdn = NULL;
2758 addr->ocsp = OCSP_NOT_REQ;
2766 /*************************************************
2767 * Main entry point *
2768 *************************************************/
2770 /* See local README for interface details. As this is a remote transport, it is
2771 given a chain of addresses to be delivered in one connection, if possible. It
2772 always returns TRUE, indicating that each address has its own independent
2773 status set, except if there is a setting up problem, in which case it returns
2777 smtp_transport_entry(
2778 transport_instance *tblock, /* data for this instantiation */
2779 address_item *addrlist) /* addresses we are working on */
2783 int hosts_defer = 0;
2785 int hosts_looked_up = 0;
2786 int hosts_retry = 0;
2787 int hosts_serial = 0;
2788 int hosts_total = 0;
2789 int total_hosts_tried = 0;
2791 BOOL expired = TRUE;
2792 BOOL continuing = continue_hostname != NULL;
2793 uschar *expanded_hosts = NULL;
2795 uschar *tid = string_sprintf("%s transport", tblock->name);
2796 smtp_transport_options_block *ob =
2797 (smtp_transport_options_block *)(tblock->options_block);
2798 host_item *hostlist = addrlist->host_list;
2799 host_item *host = NULL;
2803 debug_printf("%s transport entered\n", tblock->name);
2804 for (addr = addrlist; addr != NULL; addr = addr->next)
2805 debug_printf(" %s\n", addr->address);
2806 if (continuing) debug_printf("already connected to %s [%s]\n",
2807 continue_hostname, continue_host_address);
2810 /* Set the flag requesting that these hosts be added to the waiting
2811 database if the delivery fails temporarily or if we are running with
2812 queue_smtp or a 2-stage queue run. This gets unset for certain
2813 kinds of error, typically those that are specific to the message. */
2815 update_waiting = TRUE;
2817 /* If a host list is not defined for the addresses - they must all have the
2818 same one in order to be passed to a single transport - or if the transport has
2819 a host list with hosts_override set, use the host list supplied with the
2820 transport. It is an error for this not to exist. */
2822 if (hostlist == NULL || (ob->hosts_override && ob->hosts != NULL))
2824 if (ob->hosts == NULL)
2826 addrlist->message = string_sprintf("%s transport called with no hosts set",
2828 addrlist->transport_return = PANIC;
2829 return FALSE; /* Only top address has status */
2832 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
2835 /* If the transport's host list contains no '$' characters, and we are not
2836 randomizing, it is fixed and therefore a chain of hosts can be built once
2837 and for all, and remembered for subsequent use by other calls to this
2838 transport. If, on the other hand, the host list does contain '$', or we are
2839 randomizing its order, we have to rebuild it each time. In the fixed case,
2840 as the hosts string will never be used again, it doesn't matter that we
2841 replace all the : characters with zeros. */
2843 if (ob->hostlist == NULL)
2845 uschar *s = ob->hosts;
2847 if (Ustrchr(s, '$') != NULL)
2849 expanded_hosts = expand_string(s);
2850 if (expanded_hosts == NULL)
2852 addrlist->message = string_sprintf("failed to expand list of hosts "
2853 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
2854 addrlist->transport_return = search_find_defer? DEFER : PANIC;
2855 return FALSE; /* Only top address has status */
2857 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
2858 "\"%s\"\n", s, expanded_hosts);
2862 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
2864 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
2866 /* Check that the expansion yielded something useful. */
2867 if (hostlist == NULL)
2870 string_sprintf("%s transport has empty hosts setting", tblock->name);
2871 addrlist->transport_return = PANIC;
2872 return FALSE; /* Only top address has status */
2875 /* If there was no expansion of hosts, save the host list for
2878 if (expanded_hosts == NULL) ob->hostlist = hostlist;
2881 /* This is not the first time this transport has been run in this delivery;
2882 the host list was built previously. */
2884 else hostlist = ob->hostlist;
2887 /* The host list was supplied with the address. If hosts_randomize is set, we
2888 must sort it into a random order if it did not come from MX records and has not
2889 already been randomized (but don't bother if continuing down an existing
2892 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continuing)
2894 host_item *newlist = NULL;
2895 while (hostlist != NULL)
2897 host_item *h = hostlist;
2898 hostlist = hostlist->next;
2900 h->sort_key = random_number(100);
2902 if (newlist == NULL)
2907 else if (h->sort_key < newlist->sort_key)
2914 host_item *hh = newlist;
2915 while (hh->next != NULL)
2917 if (h->sort_key < hh->next->sort_key) break;
2925 hostlist = addrlist->host_list = newlist;
2929 /* Sort out the default port. */
2931 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
2934 /* For each host-plus-IP-address on the list:
2936 . If this is a continued delivery and the host isn't the one with the
2937 current connection, skip.
2939 . If the status is unusable (i.e. previously failed or retry checked), skip.
2941 . If no IP address set, get the address, either by turning the name into
2942 an address, calling gethostbyname if gethostbyname is on, or by calling
2943 the DNS. The DNS may yield multiple addresses, in which case insert the
2944 extra ones into the list.
2946 . Get the retry data if not previously obtained for this address and set the
2947 field which remembers the state of this address. Skip if the retry time is
2948 not reached. If not, remember whether retry data was found. The retry string
2949 contains both the name and the IP address.
2951 . Scan the list of addresses and mark those whose status is DEFER as
2952 PENDING_DEFER. These are the only ones that will be processed in this cycle
2955 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
2956 Some addresses may be successfully delivered, others may fail, and yet
2957 others may get temporary errors and so get marked DEFER.
2959 . The return from the delivery attempt is OK if a connection was made and a
2960 valid SMTP dialogue was completed. Otherwise it is DEFER.
2962 . If OK, add a "remove" retry item for this host/IPaddress, if any.
2964 . If fail to connect, or other defer state, add a retry item.
2966 . If there are any addresses whose status is still DEFER, carry on to the
2967 next host/IPaddress, unless we have tried the number of hosts given
2968 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
2969 there is some fancy logic for hosts_max_try that means its limit can be
2970 overstepped in some circumstances.
2972 If we get to the end of the list, all hosts have deferred at least one address,
2973 or not reached their retry times. If delay_after_cutoff is unset, it requests a
2974 delivery attempt to those hosts whose last try was before the arrival time of
2975 the current message. To cope with this, we have to go round the loop a second
2976 time. After that, set the status and error data for any addresses that haven't
2977 had it set already. */
2979 for (cutoff_retry = 0; expired &&
2980 cutoff_retry < ((ob->delay_after_cutoff)? 1 : 2);
2983 host_item *nexthost = NULL;
2984 int unexpired_hosts_tried = 0;
2986 for (host = hostlist;
2988 unexpired_hosts_tried < ob->hosts_max_try &&
2989 total_hosts_tried < ob->hosts_max_try_hardlimit;
2995 BOOL serialized = FALSE;
2996 BOOL host_is_expired = FALSE;
2997 BOOL message_defer = FALSE;
2998 BOOL ifchanges = FALSE;
2999 BOOL some_deferred = FALSE;
3000 address_item *first_addr = NULL;
3001 uschar *interface = NULL;
3002 uschar *retry_host_key = NULL;
3003 uschar *retry_message_key = NULL;
3004 uschar *serialize_key = NULL;
3006 /* Default next host is next host. :-) But this can vary if the
3007 hosts_max_try limit is hit (see below). It may also be reset if a host
3008 address is looked up here (in case the host was multihomed). */
3010 nexthost = host->next;
3012 /* If the address hasn't yet been obtained from the host name, look it up
3013 now, unless the host is already marked as unusable. If it is marked as
3014 unusable, it means that the router was unable to find its IP address (in
3015 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
3016 the lookup failed last time. We don't get this far if *all* MX records
3017 point to non-existent hosts; that is treated as a hard error.
3019 We can just skip this host entirely. When the hosts came from the router,
3020 the address will timeout based on the other host(s); when the address is
3021 looked up below, there is an explicit retry record added.
3023 Note that we mustn't skip unusable hosts if the address is not unset; they
3024 may be needed as expired hosts on the 2nd time round the cutoff loop. */
3026 if (host->address == NULL)
3028 int new_port, flags;
3030 uschar *canonical_name;
3032 if (host->status >= hstatus_unusable)
3034 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
3039 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
3041 /* The host name is permitted to have an attached port. Find it, and
3042 strip it from the name. Just remember it for now. */
3044 new_port = host_item_get_port(host);
3046 /* Count hosts looked up */
3050 /* Find by name if so configured, or if it's an IP address. We don't
3051 just copy the IP address, because we need the test-for-local to happen. */
3053 flags = HOST_FIND_BY_A;
3054 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
3055 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
3057 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
3058 rc = host_find_byname(host, NULL, flags, &canonical_name, TRUE);
3060 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
3061 ob->dnssec_request_domains, ob->dnssec_require_domains,
3062 &canonical_name, NULL);
3064 /* Update the host (and any additional blocks, resulting from
3065 multihoming) with a host-specific port, if any. */
3067 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
3069 /* Failure to find the host at this time (usually DNS temporary failure)
3070 is really a kind of routing failure rather than a transport failure.
3071 Therefore we add a retry item of the routing kind, not to stop us trying
3072 to look this name up here again, but to ensure the address gets timed
3073 out if the failures go on long enough. A complete failure at this point
3074 commonly points to a configuration error, but the best action is still
3075 to carry on for the next host. */
3077 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
3079 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
3081 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
3082 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
3083 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
3084 host->status = hstatus_unusable;
3086 for (addr = addrlist; addr != NULL; addr = addr->next)
3088 if (addr->transport_return != DEFER) continue;
3089 addr->basic_errno = ERRNO_UNKNOWNHOST;
3091 string_sprintf("failed to lookup IP address for %s", host->name);
3096 /* If the host is actually the local host, we may have a problem, or
3097 there may be some cunning configuration going on. In the problem case,
3098 log things and give up. The default transport status is already DEFER. */
3100 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
3102 for (addr = addrlist; addr != NULL; addr = addr->next)
3104 addr->basic_errno = 0;
3105 addr->message = string_sprintf("%s transport found host %s to be "
3106 "local", tblock->name, host->name);
3110 } /* End of block for IP address lookup */
3112 /* If this is a continued delivery, we are interested only in the host
3113 which matches the name of the existing open channel. The check is put
3114 here after the local host lookup, in case the name gets expanded as a
3115 result of the lookup. Set expired FALSE, to save the outer loop executing
3118 if (continuing && (Ustrcmp(continue_hostname, host->name) != 0 ||
3119 Ustrcmp(continue_host_address, host->address) != 0))
3122 continue; /* With next host */
3125 /* Reset the default next host in case a multihomed host whose addresses
3126 are not looked up till just above added to the host list. */
3128 nexthost = host->next;
3130 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
3131 domain is in queue_smtp_domains, we don't actually want to attempt any
3132 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
3133 there is a lookup defer in queue_smtp_domains, proceed as if the domain
3134 were not in it. We don't want to hold up all SMTP deliveries! Except when
3135 doing a two-stage queue run, don't do this if forcing. */
3137 if ((!deliver_force || queue_2stage) && (queue_smtp ||
3138 match_isinlist(addrlist->domain, &queue_smtp_domains, 0,
3139 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
3142 for (addr = addrlist; addr != NULL; addr = addr->next)
3144 if (addr->transport_return != DEFER) continue;
3145 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
3147 continue; /* With next host */
3150 /* Count hosts being considered - purely for an intelligent comment
3151 if none are usable. */
3155 /* Set $host and $host address now in case they are needed for the
3156 interface expansion or the serialize_hosts check; they remain set if an
3157 actual delivery happens. */
3159 deliver_host = host->name;
3160 deliver_host_address = host->address;
3161 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
3162 : host->dnssec == DS_NO ? US"no"
3165 /* Set up a string for adding to the retry key if the port number is not
3166 the standard SMTP port. A host may have its own port setting that overrides
3169 pistring = string_sprintf(":%d", (host->port == PORT_NONE)?
3171 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
3173 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
3174 string changes upon expansion, we must add it to the key that is used for
3175 retries, because connections to the same host from a different interface
3176 should be treated separately. */
3178 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET : AF_INET6;
3179 if (!smtp_get_interface(ob->interface, host_af, addrlist, &ifchanges,
3182 if (ifchanges) pistring = string_sprintf("%s/%s", pistring, interface);
3184 /* The first time round the outer loop, check the status of the host by
3185 inspecting the retry data. The second time round, we are interested only
3186 in expired hosts that haven't been tried since this message arrived. */
3188 if (cutoff_retry == 0)
3191 /* Ensure the status of the address is set by checking retry data if
3192 necessary. There may be host-specific retry data (applicable to all
3193 messages) and also data for retries of a specific message at this host.
3194 If either of these retry records are actually read, the keys used are
3195 returned to save recomputing them later. */
3197 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3198 US"retry_include_ip_address", ob->retry_include_ip_address,
3199 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3200 continue; /* with next host */
3202 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
3203 incl_ip, &retry_host_key, &retry_message_key);
3205 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
3206 (host->address == NULL)? US"" : host->address, pistring,
3207 (host->status == hstatus_usable)? "usable" :
3208 (host->status == hstatus_unusable)? "unusable" :
3209 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
3211 /* Skip this address if not usable at this time, noting if it wasn't
3212 actually expired, both locally and in the address. */
3214 switch (host->status)
3216 case hstatus_unusable:
3218 setflag(addrlist, af_retry_skipped);
3221 case hstatus_unusable_expired:
3224 case hwhy_retry: hosts_retry++; break;
3225 case hwhy_failed: hosts_fail++; break;
3226 case hwhy_deferred: hosts_defer++; break;
3229 /* If there was a retry message key, implying that previously there
3230 was a message-specific defer, we don't want to update the list of
3231 messages waiting for these hosts. */
3233 if (retry_message_key != NULL) update_waiting = FALSE;
3234 continue; /* With the next host or IP address */
3238 /* Second time round the loop: if the address is set but expired, and
3239 the message is newer than the last try, let it through. */
3243 if (host->address == NULL ||
3244 host->status != hstatus_unusable_expired ||
3245 host->last_try > received_time)
3248 debug_printf("trying expired host %s [%s]%s\n",
3249 host->name, host->address, pistring);
3250 host_is_expired = TRUE;
3253 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
3254 it remains TRUE only if all hosts are expired and none are actually tried.
3259 /* If this host is listed as one to which access must be serialized,
3260 see if another Exim process has a connection to it, and if so, skip
3261 this host. If not, update the database to record our connection to it
3262 and remember this for later deletion. Do not do any of this if we are
3263 sending the message down a pre-existing connection. */
3266 verify_check_given_host(&ob->serialize_hosts, host) == OK)
3268 serialize_key = string_sprintf("host-serialize-%s", host->name);
3269 if (!enq_start(serialize_key))
3272 debug_printf("skipping host %s because another Exim process "
3273 "is connected to it\n", host->name);
3280 /* OK, we have an IP address that is not waiting for its retry time to
3281 arrive (it might be expired) OR (second time round the loop) we have an
3282 expired host that hasn't been tried since the message arrived. Have a go
3283 at delivering the message to it. First prepare the addresses by flushing
3284 out the result of previous attempts, and finding the first address that
3285 is still to be delivered. */
3287 first_addr = prepare_addresses(addrlist, host);
3289 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
3290 message_id, host->name, host->address, addrlist->address,
3291 (addrlist->next == NULL)? "" : ", ...");
3293 set_process_info("delivering %s to %s [%s] (%s%s)",
3294 message_id, host->name, host->address, addrlist->address,
3295 (addrlist->next == NULL)? "" : ", ...");
3297 /* This is not for real; don't do the delivery. If there are
3298 any remaining hosts, list them. */
3303 set_errno(addrlist, 0, NULL, OK, FALSE, NULL);
3304 for (addr = addrlist; addr != NULL; addr = addr->next)
3306 addr->host_used = host;
3307 addr->special_action = '*';
3308 addr->message = US"delivery bypassed by -N option";
3312 debug_printf("*** delivery by %s transport bypassed by -N option\n"
3313 "*** host and remaining hosts:\n", tblock->name);
3314 for (host2 = host; host2 != NULL; host2 = host2->next)
3315 debug_printf(" %s [%s]\n", host2->name,
3316 (host2->address == NULL)? US"unset" : host2->address);
3321 /* This is for real. If the host is expired, we don't count it for
3322 hosts_max_retry. This ensures that all hosts must expire before an address
3323 is timed out, unless hosts_max_try_hardlimit (which protects against
3324 lunatic DNS configurations) is reached.
3326 If the host is not expired and we are about to hit the hosts_max_retry
3327 limit, check to see if there is a subsequent hosts with a different MX
3328 value. If so, make that the next host, and don't count this one. This is a
3329 heuristic to make sure that different MXs do get tried. With a normal kind
3330 of retry rule, they would get tried anyway when the earlier hosts were
3331 delayed, but if the domain has a "retry every time" type of rule - as is
3332 often used for the the very large ISPs, that won't happen. */
3336 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
3340 debug_printf("hosts_max_try limit reached with this host\n");
3341 for (h = host; h != NULL; h = h->next)
3342 if (h->mx != host->mx) break;
3346 unexpired_hosts_tried--;
3347 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
3348 "and will be tried\n");
3352 /* Attempt the delivery. */
3354 total_hosts_tried++;
3355 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
3356 expanded_hosts != NULL, &message_defer, FALSE);
3359 OK => connection made, each address contains its result;
3360 message_defer is set for message-specific defers (when all
3361 recipients are marked defer)
3362 DEFER => there was a non-message-specific delivery problem;
3363 ERROR => there was a problem setting up the arguments for a filter,
3364 or there was a problem with expanding added headers
3367 /* If the result is not OK, there was a non-message-specific problem.
3368 If the result is DEFER, we need to write to the logs saying what happened
3369 for this particular host, except in the case of authentication and TLS
3370 failures, where the log has already been written. If all hosts defer a
3371 general message is written at the end. */
3373 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL &&
3374 first_addr->basic_errno != ERRNO_TLSFAILURE)
3375 write_logs(first_addr, host);
3377 #ifdef EXPERIMENTAL_EVENT
3379 deferred_event_raise(first_addr, host);
3382 /* If STARTTLS was accepted, but there was a failure in setting up the
3383 TLS session (usually a certificate screwup), and the host is not in
3384 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
3385 TLS forcibly turned off. We have to start from scratch with a new SMTP
3386 connection. That's why the retry is done from here, not from within
3387 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
3388 session, so the in-clear transmission after those errors, if permitted,
3389 happens inside smtp_deliver().] */
3393 && first_addr->basic_errno == ERRNO_TLSFAILURE
3394 && ob->tls_tempfail_tryclear
3395 && verify_check_given_host(&ob->hosts_require_tls, host) != OK
3398 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
3399 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
3400 first_addr = prepare_addresses(addrlist, host);
3401 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
3402 expanded_hosts != NULL, &message_defer, TRUE);
3403 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
3404 write_logs(first_addr, host);
3405 # ifdef EXPERIMENTAL_EVENT
3407 deferred_event_raise(first_addr, host);
3410 #endif /*SUPPORT_TLS*/
3413 /* Delivery attempt finished */
3415 rs = (rc == OK)? US"OK" : (rc == DEFER)? US"DEFER" : (rc == ERROR)?
3418 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
3419 message_id, host->name, host->address, addrlist->address,
3420 (addrlist->next == NULL)? "" : " (& others)", rs);
3422 /* Release serialization if set up */
3424 if (serialized) enq_end(serialize_key);
3426 /* If the result is DEFER, or if a host retry record is known to exist, we
3427 need to add an item to the retry chain for updating the retry database
3428 at the end of delivery. We only need to add the item to the top address,
3429 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
3430 for any other delivery attempts using the same address. (It is copied into
3431 the unusable tree at the outer level, so even if different address blocks
3432 contain the same address, it still won't get tried again.) */
3434 if (rc == DEFER || retry_host_key != NULL)
3436 int delete_flag = (rc != DEFER)? rf_delete : 0;
3437 if (retry_host_key == NULL)
3440 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3441 US"retry_include_ip_address", ob->retry_include_ip_address,
3442 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3443 incl_ip = TRUE; /* error; use most-specific retry record */
3445 retry_host_key = incl_ip ?
3446 string_sprintf("T:%S:%s%s", host->name, host->address, pistring) :
3447 string_sprintf("T:%S%s", host->name, pistring);
3450 /* If a delivery of another message over an existing SMTP connection
3451 yields DEFER, we do NOT set up retry data for the host. This covers the
3452 case when there are delays in routing the addresses in the second message
3453 that are so long that the server times out. This is alleviated by not
3454 routing addresses that previously had routing defers when handling an
3455 existing connection, but even so, this case may occur (e.g. if a
3456 previously happily routed address starts giving routing defers). If the
3457 host is genuinely down, another non-continued message delivery will
3458 notice it soon enough. */
3460 if (delete_flag != 0 || !continuing)
3461 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
3463 /* We may have tried an expired host, if its retry time has come; ensure
3464 the status reflects the expiry for the benefit of any other addresses. */
3468 host->status = (host_is_expired)?
3469 hstatus_unusable_expired : hstatus_unusable;
3470 host->why = hwhy_deferred;
3474 /* If message_defer is set (host was OK, but every recipient got deferred
3475 because of some message-specific problem), or if that had happened
3476 previously so that a message retry key exists, add an appropriate item
3477 to the retry chain. Note that if there was a message defer but now there is
3478 a host defer, the message defer record gets deleted. That seems perfectly
3479 reasonable. Also, stop the message from being remembered as waiting
3480 for specific hosts. */
3482 if (message_defer || retry_message_key != NULL)
3484 int delete_flag = message_defer? 0 : rf_delete;
3485 if (retry_message_key == NULL)
3488 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3489 US"retry_include_ip_address", ob->retry_include_ip_address,
3490 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3491 incl_ip = TRUE; /* error; use most-specific retry record */
3493 retry_message_key = incl_ip ?
3494 string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
3496 string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
3498 retry_add_item(addrlist, retry_message_key,
3499 rf_message | rf_host | delete_flag);
3500 update_waiting = FALSE;
3503 /* Any return other than DEFER (that is, OK or ERROR) means that the
3504 addresses have got their final statuses filled in for this host. In the OK
3505 case, see if any of them are deferred. */
3509 for (addr = addrlist; addr != NULL; addr = addr->next)
3511 if (addr->transport_return == DEFER)
3513 some_deferred = TRUE;
3519 /* If no addresses deferred or the result was ERROR, return. We do this for
3520 ERROR because a failing filter set-up or add_headers expansion is likely to
3521 fail for any host we try. */
3523 if (rc == ERROR || (rc == OK && !some_deferred))
3525 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3526 return TRUE; /* Each address has its status */
3529 /* If the result was DEFER or some individual addresses deferred, let
3530 the loop run to try other hosts with the deferred addresses, except for the
3531 case when we were trying to deliver down an existing channel and failed.
3532 Don't try any other hosts in this case. */
3534 if (continuing) break;
3536 /* If the whole delivery, or some individual addresses, were deferred and
3537 there are more hosts that could be tried, do not count this host towards
3538 the hosts_max_try limit if the age of the message is greater than the
3539 maximum retry time for this host. This means we may try try all hosts,
3540 ignoring the limit, when messages have been around for some time. This is
3541 important because if we don't try all hosts, the address will never time
3542 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
3544 if ((rc == DEFER || some_deferred) && nexthost != NULL)
3547 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
3549 if (retry != NULL && retry->rules != NULL)
3551 retry_rule *last_rule;
3552 for (last_rule = retry->rules;
3553 last_rule->next != NULL;
3554 last_rule = last_rule->next);
3555 timedout = time(NULL) - received_time > last_rule->timeout;
3557 else timedout = TRUE; /* No rule => timed out */
3561 unexpired_hosts_tried--;
3562 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
3563 "hosts_max_try (message older than host's retry time)\n");
3566 } /* End of loop for trying multiple hosts. */
3568 /* This is the end of the loop that repeats iff expired is TRUE and
3569 ob->delay_after_cutoff is FALSE. The second time round we will
3570 try those hosts that haven't been tried since the message arrived. */
3574 debug_printf("all IP addresses skipped or deferred at least one address\n");
3575 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
3576 debug_printf("retrying IP addresses not tried since message arrived\n");
3581 /* Get here if all IP addresses are skipped or defer at least one address. In
3582 MUA wrapper mode, this will happen only for connection or other non-message-
3583 specific failures. Force the delivery status for all addresses to FAIL. */
3587 for (addr = addrlist; addr != NULL; addr = addr->next)
3588 addr->transport_return = FAIL;
3592 /* In the normal, non-wrapper case, add a standard message to each deferred
3593 address if there hasn't been an error, that is, if it hasn't actually been
3594 tried this time. The variable "expired" will be FALSE if any deliveries were
3595 actually tried, or if there was at least one host that was not expired. That
3596 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
3597 a delivery has been tried, an error code will be set, and the failing of the
3598 message is handled by the retry code later.
3600 If queue_smtp is set, or this transport was called to send a subsequent message
3601 down an existing TCP/IP connection, and something caused the host not to be
3602 found, we end up here, but can detect these cases and handle them specially. */
3604 for (addr = addrlist; addr != NULL; addr = addr->next)
3606 /* If host is not NULL, it means that we stopped processing the host list
3607 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
3608 means we need to behave as if some hosts were skipped because their retry
3609 time had not come. Specifically, this prevents the address from timing out.
3610 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
3611 hosts were tried. */
3615 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
3618 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
3619 "hosts were tried\n");
3624 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
3625 setflag(addr, af_retry_skipped);
3629 if (queue_smtp) /* no deliveries attempted */
3631 addr->transport_return = DEFER;
3632 addr->basic_errno = 0;
3633 addr->message = US"SMTP delivery explicitly queued";
3636 else if (addr->transport_return == DEFER &&
3637 (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0) &&
3638 addr->message == NULL)
3640 addr->basic_errno = ERRNO_HRETRY;
3641 if (continue_hostname != NULL)
3643 addr->message = US"no host found for existing SMTP connection";
3647 setflag(addr, af_pass_message); /* This is not a security risk */
3648 addr->message = (ob->delay_after_cutoff)?
3649 US"retry time not reached for any host after a long failure period" :
3650 US"all hosts have been failing for a long time and were last tried "
3651 "after this message arrived";
3653 /* If we are already using fallback hosts, or there are no fallback hosts
3654 defined, convert the result to FAIL to cause a bounce. */
3656 if (addr->host_list == addr->fallback_hosts ||
3657 addr->fallback_hosts == NULL)
3658 addr->transport_return = FAIL;
3662 if (hosts_retry == hosts_total)
3663 addr->message = US"retry time not reached for any host";
3664 else if (hosts_fail == hosts_total)
3665 addr->message = US"all host address lookups failed permanently";
3666 else if (hosts_defer == hosts_total)
3667 addr->message = US"all host address lookups failed temporarily";
3668 else if (hosts_serial == hosts_total)
3669 addr->message = US"connection limit reached for all hosts";
3670 else if (hosts_fail+hosts_defer == hosts_total)
3671 addr->message = US"all host address lookups failed";
3672 else addr->message = US"some host address lookups failed and retry time "
3673 "not reached for other hosts or connection limit reached";
3678 /* Update the database which keeps information about which messages are waiting
3679 for which hosts to become available. For some message-specific errors, the
3680 update_waiting flag is turned off because we don't want follow-on deliveries in
3681 those cases. If this transport instance is explicitly limited to one message
3682 per connection then follow-on deliveries are not possible and there's no need
3683 to create/update the per-transport wait-<transport_name> database. */
3685 if (update_waiting && tblock->connection_max_messages != 1)
3686 transport_update_waiting(hostlist, tblock->name);
3690 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3692 return TRUE; /* Each address has its status */
3697 /* End of transport/smtp.c */