1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2016 */
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.dkim_canon) },
48 { "dkim_domain", opt_stringptr,
49 (void *)offsetof(smtp_transport_options_block, dkim.dkim_domain) },
50 { "dkim_private_key", opt_stringptr,
51 (void *)offsetof(smtp_transport_options_block, dkim.dkim_private_key) },
52 { "dkim_selector", opt_stringptr,
53 (void *)offsetof(smtp_transport_options_block, dkim.dkim_selector) },
54 { "dkim_sign_headers", opt_stringptr,
55 (void *)offsetof(smtp_transport_options_block, dkim.dkim_sign_headers) },
56 { "dkim_strict", opt_stringptr,
57 (void *)offsetof(smtp_transport_options_block, dkim.dkim_strict) },
59 { "dns_qualify_single", opt_bool,
60 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
61 { "dns_search_parents", opt_bool,
62 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
63 { "dnssec_request_domains", opt_stringptr,
64 (void *)offsetof(smtp_transport_options_block, dnssec.request) },
65 { "dnssec_require_domains", opt_stringptr,
66 (void *)offsetof(smtp_transport_options_block, dnssec.require) },
67 { "dscp", opt_stringptr,
68 (void *)offsetof(smtp_transport_options_block, dscp) },
69 { "fallback_hosts", opt_stringptr,
70 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
71 { "final_timeout", opt_time,
72 (void *)offsetof(smtp_transport_options_block, final_timeout) },
73 { "gethostbyname", opt_bool,
74 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
75 { "helo_data", opt_stringptr,
76 (void *)offsetof(smtp_transport_options_block, helo_data) },
77 { "hosts", opt_stringptr,
78 (void *)offsetof(smtp_transport_options_block, hosts) },
79 { "hosts_avoid_esmtp", opt_stringptr,
80 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
81 { "hosts_avoid_pipelining", opt_stringptr,
82 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
84 { "hosts_avoid_tls", opt_stringptr,
85 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
87 { "hosts_max_try", opt_int,
88 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
89 { "hosts_max_try_hardlimit", opt_int,
90 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
92 { "hosts_nopass_tls", opt_stringptr,
93 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
95 { "hosts_override", opt_bool,
96 (void *)offsetof(smtp_transport_options_block, hosts_override) },
97 { "hosts_randomize", opt_bool,
98 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
99 #if defined(SUPPORT_TLS) && !defined(DISABLE_OCSP)
100 { "hosts_request_ocsp", opt_stringptr,
101 (void *)offsetof(smtp_transport_options_block, hosts_request_ocsp) },
103 { "hosts_require_auth", opt_stringptr,
104 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
106 # ifdef EXPERIMENTAL_DANE
107 { "hosts_require_dane", opt_stringptr,
108 (void *)offsetof(smtp_transport_options_block, hosts_require_dane) },
110 # ifndef DISABLE_OCSP
111 { "hosts_require_ocsp", opt_stringptr,
112 (void *)offsetof(smtp_transport_options_block, hosts_require_ocsp) },
114 { "hosts_require_tls", opt_stringptr,
115 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
117 { "hosts_try_auth", opt_stringptr,
118 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
119 { "hosts_try_chunking", opt_stringptr,
120 (void *)offsetof(smtp_transport_options_block, hosts_try_chunking) },
121 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
122 { "hosts_try_dane", opt_stringptr,
123 (void *)offsetof(smtp_transport_options_block, hosts_try_dane) },
126 { "hosts_try_prdr", opt_stringptr,
127 (void *)offsetof(smtp_transport_options_block, hosts_try_prdr) },
130 { "hosts_verify_avoid_tls", opt_stringptr,
131 (void *)offsetof(smtp_transport_options_block, hosts_verify_avoid_tls) },
133 { "interface", opt_stringptr,
134 (void *)offsetof(smtp_transport_options_block, interface) },
135 { "keepalive", opt_bool,
136 (void *)offsetof(smtp_transport_options_block, keepalive) },
137 { "lmtp_ignore_quota", opt_bool,
138 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
139 { "max_rcpt", opt_int | opt_public,
140 (void *)offsetof(transport_instance, max_addresses) },
141 { "multi_domain", opt_expand_bool | opt_public,
142 (void *)offsetof(transport_instance, multi_domain) },
143 { "port", opt_stringptr,
144 (void *)offsetof(smtp_transport_options_block, port) },
145 { "protocol", opt_stringptr,
146 (void *)offsetof(smtp_transport_options_block, protocol) },
147 { "retry_include_ip_address", opt_expand_bool,
148 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
149 { "serialize_hosts", opt_stringptr,
150 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
151 { "size_addition", opt_int,
152 (void *)offsetof(smtp_transport_options_block, size_addition) }
154 ,{ "socks_proxy", opt_stringptr,
155 (void *)offsetof(smtp_transport_options_block, socks_proxy) }
158 ,{ "tls_certificate", opt_stringptr,
159 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
160 { "tls_crl", opt_stringptr,
161 (void *)offsetof(smtp_transport_options_block, tls_crl) },
162 { "tls_dh_min_bits", opt_int,
163 (void *)offsetof(smtp_transport_options_block, tls_dh_min_bits) },
164 { "tls_privatekey", opt_stringptr,
165 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
166 { "tls_require_ciphers", opt_stringptr,
167 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
168 { "tls_sni", opt_stringptr,
169 (void *)offsetof(smtp_transport_options_block, tls_sni) },
170 { "tls_tempfail_tryclear", opt_bool,
171 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
172 { "tls_try_verify_hosts", opt_stringptr,
173 (void *)offsetof(smtp_transport_options_block, tls_try_verify_hosts) },
174 { "tls_verify_cert_hostnames", opt_stringptr,
175 (void *)offsetof(smtp_transport_options_block,tls_verify_cert_hostnames)},
176 { "tls_verify_certificates", opt_stringptr,
177 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) },
178 { "tls_verify_hosts", opt_stringptr,
179 (void *)offsetof(smtp_transport_options_block, tls_verify_hosts) }
183 /* Size of the options list. An extern variable has to be used so that its
184 address can appear in the tables drtables.c. */
186 int smtp_transport_options_count =
187 sizeof(smtp_transport_options)/sizeof(optionlist);
189 /* Default private options block for the smtp transport. */
191 smtp_transport_options_block smtp_transport_option_defaults = {
193 NULL, /* fallback_hosts */
195 NULL, /* fallback_hostlist */
196 NULL, /* authenticated_sender */
197 US"$primary_hostname", /* helo_data */
198 NULL, /* interface */
200 US"smtp", /* protocol */
202 NULL, /* serialize_hosts */
203 NULL, /* hosts_try_auth */
204 NULL, /* hosts_require_auth */
205 US"*", /* hosts_try_chunking */
206 #ifdef EXPERIMENTAL_DANE
207 NULL, /* hosts_try_dane */
208 NULL, /* hosts_require_dane */
211 US"*", /* hosts_try_prdr */
214 US"*", /* hosts_request_ocsp (except under DANE; tls_client_start()) */
215 NULL, /* hosts_require_ocsp */
217 NULL, /* hosts_require_tls */
218 NULL, /* hosts_avoid_tls */
219 NULL, /* hosts_verify_avoid_tls */
220 NULL, /* hosts_avoid_pipelining */
221 NULL, /* hosts_avoid_esmtp */
222 NULL, /* hosts_nopass_tls */
223 5*60, /* command_timeout */
224 5*60, /* connect_timeout; shorter system default overrides */
225 5*60, /* data timeout */
226 10*60, /* final timeout */
227 1024, /* size_addition */
228 5, /* hosts_max_try */
229 50, /* hosts_max_try_hardlimit */
230 TRUE, /* address_retry_include_sender */
231 FALSE, /* allow_localhost */
232 FALSE, /* authenticated_sender_force */
233 FALSE, /* gethostbyname */
234 TRUE, /* dns_qualify_single */
235 FALSE, /* dns_search_parents */
236 { NULL, NULL }, /* dnssec_domains {request,require} */
237 TRUE, /* delay_after_cutoff */
238 FALSE, /* hosts_override */
239 FALSE, /* hosts_randomize */
240 TRUE, /* keepalive */
241 FALSE, /* lmtp_ignore_quota */
242 NULL, /* expand_retry_include_ip_address */
243 TRUE /* retry_include_ip_address */
245 ,NULL /* socks_proxy */
248 ,NULL, /* tls_certificate */
250 NULL, /* tls_privatekey */
251 NULL, /* tls_require_ciphers */
253 US"system", /* tls_verify_certificates */
254 EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
255 /* tls_dh_min_bits */
256 TRUE, /* tls_tempfail_tryclear */
257 NULL, /* tls_verify_hosts */
258 US"*", /* tls_try_verify_hosts */
259 US"*" /* tls_verify_cert_hostnames */
262 , {NULL, /* dkim_canon */
263 NULL, /* dkim_domain */
264 NULL, /* dkim_private_key */
265 NULL, /* dkim_selector */
266 NULL, /* dkim_sign_headers */
267 NULL} /* dkim_strict */
271 /* some DSN flags for use later */
273 static int rf_list[] = {rf_notify_never, rf_notify_success,
274 rf_notify_failure, rf_notify_delay };
276 static uschar *rf_names[] = { US"NEVER", US"SUCCESS", US"FAILURE", US"DELAY" };
282 static uschar *smtp_command; /* Points to last cmd for error messages */
283 static uschar *mail_command; /* Points to MAIL cmd for error messages */
284 static BOOL update_waiting; /* TRUE to update the "wait" database */
285 static BOOL pipelining_active; /* current transaction is in pipe mode */
288 /*************************************************
289 * Setup entry point *
290 *************************************************/
292 /* This function is called when the transport is about to be used,
293 but before running it in a sub-process. It is used for two things:
295 (1) To set the fallback host list in addresses, when delivering.
296 (2) To pass back the interface, port, protocol, and other options, for use
297 during callout verification.
300 tblock pointer to the transport instance block
301 addrlist list of addresses about to be transported
302 tf if not NULL, pointer to block in which to return options
303 uid the uid that will be set (not used)
304 gid the gid that will be set (not used)
305 errmsg place for error message (not used)
307 Returns: OK always (FAIL, DEFER not used)
311 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
312 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
314 smtp_transport_options_block *ob =
315 (smtp_transport_options_block *)(tblock->options_block);
317 errmsg = errmsg; /* Keep picky compilers happy */
321 /* Pass back options if required. This interface is getting very messy. */
325 tf->interface = ob->interface;
327 tf->protocol = ob->protocol;
328 tf->hosts = ob->hosts;
329 tf->hosts_override = ob->hosts_override;
330 tf->hosts_randomize = ob->hosts_randomize;
331 tf->gethostbyname = ob->gethostbyname;
332 tf->qualify_single = ob->dns_qualify_single;
333 tf->search_parents = ob->dns_search_parents;
334 tf->helo_data = ob->helo_data;
337 /* Set the fallback host list for all the addresses that don't have fallback
338 host lists, provided that the local host wasn't present in the original host
341 if (!testflag(addrlist, af_local_host_removed))
343 for (; addrlist != NULL; addrlist = addrlist->next)
344 if (addrlist->fallback_hosts == NULL)
345 addrlist->fallback_hosts = ob->fallback_hostlist;
353 /*************************************************
354 * Initialization entry point *
355 *************************************************/
357 /* Called for each instance, after its options have been read, to
358 enable consistency checks to be done, or anything else that needs
361 Argument: pointer to the transport instance block
366 smtp_transport_init(transport_instance *tblock)
368 smtp_transport_options_block *ob =
369 (smtp_transport_options_block *)(tblock->options_block);
371 /* Retry_use_local_part defaults FALSE if unset */
373 if (tblock->retry_use_local_part == TRUE_UNSET)
374 tblock->retry_use_local_part = FALSE;
376 /* Set the default port according to the protocol */
378 if (ob->port == NULL)
379 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
380 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
382 /* Set up the setup entry point, to be called before subprocesses for this
385 tblock->setup = smtp_transport_setup;
387 /* Complain if any of the timeouts are zero. */
389 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
390 ob->final_timeout <= 0)
391 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
392 "command, data, or final timeout value is zero for %s transport",
395 /* If hosts_override is set and there are local hosts, set the global
396 flag that stops verify from showing router hosts. */
398 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
400 /* If there are any fallback hosts listed, build a chain of host items
401 for them, but do not do any lookups at this time. */
403 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
410 /*************************************************
411 * Set delivery info into all active addresses *
412 *************************************************/
414 /* Only addresses whose status is >= PENDING are relevant. A lesser
415 status means that an address is not currently being processed.
418 addrlist points to a chain of addresses
419 errno_value to put in each address's errno field
420 msg to put in each address's message field
421 rc to put in each address's transport_return field
422 pass_message if TRUE, set the "pass message" flag in the address
423 host if set, mark addrs as having used this host
424 smtp_greeting from peer
425 helo_response from peer
427 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
428 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
429 this particular type of timeout.
435 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
436 BOOL pass_message, host_item * host
437 #ifdef EXPERIMENTAL_DSN_INFO
438 , const uschar * smtp_greeting, const uschar * helo_response
444 if (errno_value == ERRNO_CONNECTTIMEOUT)
446 errno_value = ETIMEDOUT;
447 orvalue = RTEF_CTOUT;
449 for (addr = addrlist; addr; addr = addr->next)
450 if (addr->transport_return >= PENDING)
452 addr->basic_errno = errno_value;
453 addr->more_errno |= orvalue;
457 if (pass_message) setflag(addr, af_pass_message);
459 addr->transport_return = rc;
462 addr->host_used = host;
463 #ifdef EXPERIMENTAL_DSN_INFO
465 {uschar * s = Ustrchr(smtp_greeting, '\n'); if (s) *s = '\0';}
466 addr->smtp_greeting = smtp_greeting;
469 {uschar * s = Ustrchr(helo_response, '\n'); if (s) *s = '\0';}
470 addr->helo_response = helo_response;
477 set_errno_nohost(address_item *addrlist, int errno_value, uschar *msg, int rc,
480 set_errno(addrlist, errno_value, msg, rc, pass_message, NULL
481 #ifdef EXPERIMENTAL_DSN_INFO
488 /*************************************************
489 * Check an SMTP response *
490 *************************************************/
492 /* This function is given an errno code and the SMTP response buffer
493 to analyse, together with the host identification for generating messages. It
494 sets an appropriate message and puts the first digit of the response code into
495 the yield variable. If no response was actually read, a suitable digit is
499 host the current host, to get its name for messages
500 errno_value pointer to the errno value
501 more_errno from the top address for use with ERRNO_FILTER_FAIL
502 buffer the SMTP response buffer
503 yield where to put a one-digit SMTP response code
504 message where to put an errror message
505 pass_message set TRUE if message is an SMTP response
507 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
511 check_response(host_item *host, int *errno_value, int more_errno,
512 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
514 uschar * pl = pipelining_active ? US"pipelined " : US"";
516 *yield = '4'; /* Default setting is to give a temporary error */
518 /* Handle response timeout */
520 if (*errno_value == ETIMEDOUT)
522 *message = US string_sprintf("SMTP timeout after %s%s",
524 if (transport_count > 0)
525 *message = US string_sprintf("%s (%d bytes written)", *message,
530 /* Handle malformed SMTP response */
532 if (*errno_value == ERRNO_SMTPFORMAT)
534 const uschar *malfresp = string_printing(buffer);
535 while (isspace(*malfresp)) malfresp++;
536 *message = *malfresp == 0
537 ? string_sprintf("Malformed SMTP reply (an empty line) "
538 "in response to %s%s", pl, smtp_command)
539 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
540 pl, smtp_command, malfresp);
544 /* Handle a failed filter process error; can't send QUIT as we mustn't
547 if (*errno_value == ERRNO_FILTER_FAIL)
549 *message = US string_sprintf("transport filter process failed (%d)%s",
551 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
555 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
558 if (*errno_value == ERRNO_CHHEADER_FAIL)
561 US string_sprintf("failed to expand headers_add or headers_remove: %s",
562 expand_string_message);
566 /* Handle failure to write a complete data block */
568 if (*errno_value == ERRNO_WRITEINCOMPLETE)
570 *message = US string_sprintf("failed to write a data block");
575 /* Handle lack of advertised SMTPUTF8, for international message */
576 if (*errno_value == ERRNO_UTF8_FWD)
578 *message = US string_sprintf("utf8 support required but not offered for forwarding");
579 DEBUG(D_deliver|D_transport) debug_printf("%s\n", *message);
584 /* Handle error responses from the remote mailer. */
588 const uschar *s = string_printing(buffer);
589 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
590 "%s", pl, smtp_command, s);
591 *pass_message = TRUE;
596 /* No data was read. If there is no errno, this must be the EOF (i.e.
597 connection closed) case, which causes deferral. An explicit connection reset
598 error has the same effect. Otherwise, put the host's identity in the message,
599 leaving the errno value to be interpreted as well. In all cases, we have to
600 assume the connection is now dead. */
602 if (*errno_value == 0 || *errno_value == ECONNRESET)
604 *errno_value = ERRNO_SMTPCLOSED;
605 *message = US string_sprintf("Remote host closed connection "
606 "in response to %s%s", pl, smtp_command);
608 else *message = US string_sprintf("%s [%s]", host->name, host->address);
615 /*************************************************
616 * Write error message to logs *
617 *************************************************/
619 /* This writes to the main log and to the message log.
622 addr the address item containing error information
623 host the current host
629 write_logs(address_item *addr, host_item *host)
631 uschar * message = string_sprintf("H=%s [%s]", host->name, host->address);
633 if (LOGGING(outgoing_port))
634 message = string_sprintf("%s:%d", message,
635 host->port == PORT_NONE ? 25 : host->port);
638 message = string_sprintf("%s: %s", message, addr->message);
639 if (addr->basic_errno > 0)
640 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
641 log_write(0, LOG_MAIN, "%s", message);
642 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
646 const uschar * s = exim_errstr(addr->basic_errno);
647 log_write(0, LOG_MAIN, "%s %s", message, s);
648 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), message, s);
653 msglog_line(host_item * host, uschar * message)
655 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
656 host->name, host->address, message);
661 #ifndef DISABLE_EVENT
662 /*************************************************
663 * Post-defer action *
664 *************************************************/
666 /* This expands an arbitrary per-transport string.
667 It might, for example, be used to write to the database log.
670 addr the address item containing error information
671 host the current host
677 deferred_event_raise(address_item *addr, host_item *host)
679 uschar * action = addr->transport->event_action;
680 const uschar * save_domain;
686 save_domain = deliver_domain;
687 save_local = deliver_localpart;
689 /*XXX would ip & port already be set up? */
690 deliver_host_address = string_copy(host->address);
691 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
692 event_defer_errno = addr->basic_errno;
694 router_name = addr->router->name;
695 transport_name = addr->transport->name;
696 deliver_domain = addr->domain;
697 deliver_localpart = addr->local_part;
699 (void) event_raise(action, US"msg:host:defer",
701 ? addr->basic_errno > 0
702 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
703 : string_copy(addr->message)
704 : addr->basic_errno > 0
705 ? string_copy(US strerror(addr->basic_errno))
708 deliver_localpart = save_local;
709 deliver_domain = save_domain;
710 router_name = transport_name = NULL;
714 /*************************************************
715 * Synchronize SMTP responses *
716 *************************************************/
718 /* This function is called from smtp_deliver() to receive SMTP responses from
719 the server, and match them up with the commands to which they relate. When
720 PIPELINING is not in use, this function is called after every command, and is
721 therefore somewhat over-engineered, but it is simpler to use a single scheme
722 that works both with and without PIPELINING instead of having two separate sets
725 The set of commands that are buffered up with pipelining may start with MAIL
726 and may end with DATA; in between are RCPT commands that correspond to the
727 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
728 etc.) are never buffered.
730 Errors after MAIL or DATA abort the whole process leaving the response in the
731 buffer. After MAIL, pending responses are flushed, and the original command is
732 re-instated in big_buffer for error messages. For RCPT commands, the remote is
733 permitted to reject some recipient addresses while accepting others. However
734 certain errors clearly abort the whole process. Set the value in
735 transport_return to PENDING_OK if the address is accepted. If there is a
736 subsequent general error, it will get reset accordingly. If not, it will get
737 converted to OK at the end.
740 addrlist the complete address list
741 include_affixes TRUE if affixes include in RCPT
742 sync_addr ptr to the ptr of the one to start scanning at (updated)
743 host the host we are connected to
744 count the number of responses to read
746 include_sender true if 4xx retry is to include the sender it its key
747 pending_MAIL true if the first response is for MAIL
748 pending_DATA 0 if last command sent was not DATA
749 +1 if previously had a good recipient
750 -1 if not previously had a good recipient
751 inblock incoming SMTP block
752 timeout timeout value
753 buffer buffer for reading response
754 buffsize size of buffer
756 Returns: 3 if at least one address had 2xx and one had 5xx
757 2 if at least one address had 5xx but none had 2xx
758 1 if at least one host had a 2xx response, but none had 5xx
759 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
760 -1 timeout while reading RCPT response
761 -2 I/O or other non-response error for RCPT
762 -3 DATA or MAIL failed - errno and buffer set
766 sync_responses(address_item *addrlist, BOOL include_affixes,
767 address_item **sync_addr, host_item *host, int count,
768 BOOL address_retry_include_sender, BOOL pending_MAIL,
769 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
772 address_item *addr = *sync_addr;
775 /* Handle the response for a MAIL command. On error, reinstate the original
776 command in big_buffer for error message use, and flush any further pending
777 responses before returning, except after I/O errors and timeouts. */
782 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
784 DEBUG(D_transport) debug_printf("bad response for MAIL\n");
785 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
786 if (errno == 0 && buffer[0] != 0)
788 uschar flushbuffer[4096];
790 if (buffer[0] == '4')
792 save_errno = ERRNO_MAIL4XX;
793 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
797 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
799 && (errno != 0 || flushbuffer[0] == 0))
805 if (pending_DATA) count--; /* Number of RCPT responses to come */
806 while (count-- > 0) /* Mark any pending addrs with the host used */
808 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
809 addr->host_used = host;
816 if (pending_DATA) count--; /* Number of RCPT responses to come */
818 /* Read and handle the required number of RCPT responses, matching each one up
819 with an address by scanning for the next address whose status is PENDING_DEFER.
824 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
826 /* The address was accepted */
827 addr->host_used = host;
829 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
832 addr->transport_return = PENDING_OK;
834 /* If af_dr_retry_exists is set, there was a routing delay on this address;
835 ensure that any address-specific retry record is expunged. We do this both
836 for the basic key and for the version that also includes the sender. */
838 if (testflag(addr, af_dr_retry_exists))
840 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
842 retry_add_item(addr, altkey, rf_delete);
843 retry_add_item(addr, addr->address_retry_key, rf_delete);
847 /* Timeout while reading the response */
849 else if (errno == ETIMEDOUT)
851 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
852 transport_rcpt_address(addr, include_affixes));
853 set_errno_nohost(addrlist, ETIMEDOUT, message, DEFER, FALSE);
854 retry_add_item(addr, addr->address_retry_key, 0);
855 update_waiting = FALSE;
859 /* Handle other errors in obtaining an SMTP response by returning -1. This
860 will cause all the addresses to be deferred. Restore the SMTP command in
861 big_buffer for which we are checking the response, so the error message
864 else if (errno != 0 || buffer[0] == 0)
866 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
867 transport_rcpt_address(addr, include_affixes));
871 /* Handle SMTP permanent and temporary response codes. */
876 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
877 "%s", transport_rcpt_address(addr, include_affixes),
878 string_printing(buffer));
879 setflag(addr, af_pass_message);
880 msglog_line(host, addr->message);
882 /* The response was 5xx */
884 if (buffer[0] == '5')
886 addr->transport_return = FAIL;
890 /* The response was 4xx */
894 addr->transport_return = DEFER;
895 addr->basic_errno = ERRNO_RCPT4XX;
896 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
898 #ifndef DISABLE_EVENT
899 event_defer_errno = addr->more_errno;
900 msg_event_raise(US"msg:rcpt:host:defer", addr);
903 /* Log temporary errors if there are more hosts to be tried.
904 If not, log this last one in the == line. */
907 log_write(0, LOG_MAIN, "H=%s [%s]: %s", host->name, host->address, addr->message);
909 #ifndef DISABLE_EVENT
911 msg_event_raise(US"msg:rcpt:defer", addr);
914 /* Do not put this message on the list of those waiting for specific
915 hosts, as otherwise it is likely to be tried too often. */
917 update_waiting = FALSE;
919 /* Add a retry item for the address so that it doesn't get tried again
920 too soon. If address_retry_include_sender is true, add the sender address
923 if (address_retry_include_sender)
925 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
927 retry_add_item(addr, altkey, 0);
929 else retry_add_item(addr, addr->address_retry_key, 0);
932 } /* Loop for next RCPT response */
934 /* Update where to start at for the next block of responses, unless we
935 have already handled all the addresses. */
937 if (addr != NULL) *sync_addr = addr->next;
939 /* Handle a response to DATA. If we have not had any good recipients, either
940 previously or in this block, the response is ignored. */
942 if (pending_DATA != 0 &&
943 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
948 if (pending_DATA > 0 || (yield & 1) != 0)
950 if (errno == 0 && buffer[0] == '4')
952 errno = ERRNO_DATA4XX;
953 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
957 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
958 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
959 "is in use and there were no good recipients\n", msg);
962 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
963 present) received 3xx. If any RCPTs were handled and yielded anything other
964 than 4xx, yield will be set non-zero. */
971 /* Do the client side of smtp-level authentication */
974 buffer EHLO response from server (gets overwritten)
975 addrlist chain of potential addresses to deliver
976 host host to deliver to
978 ibp, obp comms channel control blocks
981 OK Success, or failed (but not required): global "smtp_authenticated" set
982 DEFER Failed authentication (and was required)
983 ERROR Internal problem
985 FAIL_SEND Failed communications - transmit
990 smtp_auth(uschar *buffer, unsigned bufsize, address_item *addrlist, host_item *host,
991 smtp_transport_options_block *ob, BOOL is_esmtp,
992 smtp_inblock *ibp, smtp_outblock *obp)
995 uschar *fail_reason = US"server did not advertise AUTH support";
997 smtp_authenticated = FALSE;
998 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
999 require_auth = verify_check_given_host(&ob->hosts_require_auth, host);
1001 if (is_esmtp && !regex_AUTH) regex_AUTH =
1002 regex_must_compile(US"\\n250[\\s\\-]AUTH\\s+([\\-\\w\\s]+)(?:\\n|$)",
1005 if (is_esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
1007 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
1008 expand_nmax = -1; /* reset */
1010 /* Must not do this check until after we have saved the result of the
1011 regex match above. */
1013 if (require_auth == OK ||
1014 verify_check_given_host(&ob->hosts_try_auth, host) == OK)
1017 fail_reason = US"no common mechanisms were found";
1019 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1021 /* Scan the configured authenticators looking for one which is configured
1022 for use as a client, which is not suppressed by client_condition, and
1023 whose name matches an authentication mechanism supported by the server.
1024 If one is found, attempt to authenticate by calling its client function.
1027 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1031 (au->client_condition != NULL &&
1032 !expand_check_condition(au->client_condition, au->name,
1033 US"client authenticator")))
1035 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1037 (au->client)? "client_condition is false" :
1038 "not configured as a client");
1042 /* Loop to scan supported server mechanisms */
1047 int len = Ustrlen(au->public_name);
1048 while (isspace(*p)) p++;
1050 if (strncmpic(au->public_name, p, len) != 0 ||
1051 (p[len] != 0 && !isspace(p[len])))
1053 while (*p != 0 && !isspace(*p)) p++;
1057 /* Found data for a listed mechanism. Call its client entry. Set
1058 a flag in the outblock so that data is overwritten after sending so
1059 that reflections don't show it. */
1061 fail_reason = US"authentication attempt(s) failed";
1062 obp->authenticating = TRUE;
1063 rc = (au->info->clientcode)(au, ibp, obp,
1064 ob->command_timeout, buffer, bufsize);
1065 obp->authenticating = FALSE;
1066 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1069 /* A temporary authentication failure must hold up delivery to
1070 this host. After a permanent authentication failure, we carry on
1071 to try other authentication methods. If all fail hard, try to
1072 deliver the message unauthenticated unless require_auth was set. */
1077 smtp_authenticated = TRUE; /* stops the outer loop */
1078 client_authenticator = au->name;
1079 if (au->set_client_id != NULL)
1080 client_authenticated_id = expand_string(au->set_client_id);
1083 /* Failure after writing a command */
1088 /* Failure after reading a response */
1091 if (errno != 0 || buffer[0] != '5') return FAIL;
1092 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1093 au->name, host->name, host->address, buffer);
1096 /* Failure by some other means. In effect, the authenticator
1097 decided it wasn't prepared to handle this case. Typically this
1098 is the result of "fail" in an expansion string. Do we need to
1099 log anything here? Feb 2006: a message is now put in the buffer
1100 if logging is required. */
1104 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1105 "authentication H=%s [%s] %s", au->name, host->name,
1106 host->address, buffer);
1109 /* Internal problem, message in buffer. */
1112 set_errno_nohost(addrlist, ERRNO_AUTHPROB, string_copy(buffer),
1117 break; /* If not authenticated, try next authenticator */
1118 } /* Loop for scanning supported server mechanisms */
1119 } /* Loop for further authenticators */
1123 /* If we haven't authenticated, but are required to, give up. */
1125 if (require_auth == OK && !smtp_authenticated)
1127 set_errno_nohost(addrlist, ERRNO_AUTHFAIL,
1128 string_sprintf("authentication required but %s", fail_reason), DEFER,
1137 /* Construct AUTH appendix string for MAIL TO */
1140 buffer to build string
1141 addrlist chain of potential addresses to deliver
1142 ob transport options
1144 Globals smtp_authenticated
1145 client_authenticated_sender
1146 Return True on error, otherwise buffer has (possibly empty) terminated string
1150 smtp_mail_auth_str(uschar *buffer, unsigned bufsize, address_item *addrlist,
1151 smtp_transport_options_block *ob)
1153 uschar *local_authenticated_sender = authenticated_sender;
1156 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n", authenticated_sender, ob->authenticated_sender, smtp_authenticated?"Y":"N");
1159 if (ob->authenticated_sender != NULL)
1161 uschar *new = expand_string(ob->authenticated_sender);
1164 if (!expand_string_forcedfail)
1166 uschar *message = string_sprintf("failed to expand "
1167 "authenticated_sender: %s", expand_string_message);
1168 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1172 else if (new[0] != 0) local_authenticated_sender = new;
1175 /* Add the authenticated sender address if present */
1177 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1178 local_authenticated_sender != NULL)
1180 string_format(buffer, bufsize, " AUTH=%s",
1181 auth_xtextencode(local_authenticated_sender,
1182 Ustrlen(local_authenticated_sender)));
1183 client_authenticated_sender = string_copy(local_authenticated_sender);
1193 #ifdef EXPERIMENTAL_DANE
1194 /* Lookup TLSA record for host/port.
1195 Return: OK success with dnssec; DANE mode
1196 DEFER Do not use this host now, may retry later
1197 FAIL_FORCED No TLSA record; DANE not usable
1198 FAIL Do not use this connection
1202 tlsa_lookup(const host_item * host, dns_answer * dnsa, BOOL dane_required)
1204 /* move this out to host.c given the similarity to dns_lookup() ? */
1206 const uschar * fullname = buffer;
1208 /* TLSA lookup string */
1209 (void)sprintf(CS buffer, "_%d._tcp.%.256s", host->port, host->name);
1211 switch (dns_lookup(dnsa, buffer, T_TLSA, &fullname))
1214 if (!dns_is_secure(dnsa))
1216 log_write(0, LOG_MAIN, "DANE error: TLSA lookup not DNSSEC");
1222 return DEFER; /* just defer this TLS'd conn */
1225 return dane_required ? FAIL : FAIL_FORCED;
1229 return dane_required ? FAIL : DEFER;
1236 typedef struct smtp_compare_s
1238 uschar *current_sender_address;
1239 struct transport_instance *tblock;
1243 Create a unique string that identifies this message, it is based on
1244 sender_address, helo_data and tls_certificate if enabled. */
1247 smtp_local_identity(uschar * sender, struct transport_instance * tblock)
1249 address_item * addr1;
1250 uschar * if1 = US"";
1251 uschar * helo1 = US"";
1253 uschar * tlsc1 = US"";
1255 uschar * save_sender_address = sender_address;
1256 uschar * local_identity = NULL;
1257 smtp_transport_options_block * ob =
1258 (smtp_transport_options_block *)tblock->options_block;
1260 sender_address = sender;
1262 addr1 = deliver_make_addr (sender, TRUE);
1263 deliver_set_expansions(addr1);
1266 if1 = expand_string(ob->interface);
1269 helo1 = expand_string(ob->helo_data);
1272 if (ob->tls_certificate)
1273 tlsc1 = expand_string(ob->tls_certificate);
1274 local_identity = string_sprintf ("%s^%s^%s", if1, helo1, tlsc1);
1276 local_identity = string_sprintf ("%s^%s", if1, helo1);
1279 deliver_set_expansions(NULL);
1280 sender_address = save_sender_address;
1282 return local_identity;
1287 /* This routine is a callback that is called from transport_check_waiting.
1288 This function will evaluate the incoming message versus the previous
1289 message. If the incoming message is using a different local identity then
1290 we will veto this new message. */
1293 smtp_are_same_identities(uschar * message_id, smtp_compare_t * s_compare)
1295 uschar * message_local_identity,
1296 * current_local_identity,
1297 * new_sender_address;
1299 current_local_identity =
1300 smtp_local_identity(s_compare->current_sender_address, s_compare->tblock);
1302 if (!(new_sender_address = deliver_get_sender_address(message_id)))
1305 message_local_identity =
1306 smtp_local_identity(new_sender_address, s_compare->tblock);
1308 return Ustrcmp(current_local_identity, message_local_identity) == 0;
1314 ehlo_response(uschar * buf, size_t bsize, uschar checks)
1317 if ( checks & PEER_OFFERED_TLS
1318 && pcre_exec(regex_STARTTLS, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1319 checks &= ~PEER_OFFERED_TLS;
1322 if ( checks & PEER_OFFERED_IGNQ
1323 && pcre_exec(regex_IGNOREQUOTA, NULL, CS buf, bsize, 0,
1324 PCRE_EOPT, NULL, 0) < 0)
1325 checks &= ~PEER_OFFERED_IGNQ;
1327 if ( checks & PEER_OFFERED_CHUNKING
1328 && pcre_exec(regex_CHUNKING, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1329 checks &= ~PEER_OFFERED_CHUNKING;
1331 #ifndef DISABLE_PRDR
1332 if ( checks & PEER_OFFERED_PRDR
1333 && pcre_exec(regex_PRDR, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1334 checks &= ~PEER_OFFERED_PRDR;
1338 if ( checks & PEER_OFFERED_UTF8
1339 && pcre_exec(regex_UTF8, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1340 checks &= ~PEER_OFFERED_UTF8;
1343 if ( checks & PEER_OFFERED_DSN
1344 && pcre_exec(regex_DSN, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1345 checks &= ~PEER_OFFERED_DSN;
1347 if ( checks & PEER_OFFERED_PIPE
1348 && pcre_exec(regex_PIPELINING, NULL, CS buf, bsize, 0,
1349 PCRE_EOPT, NULL, 0) < 0)
1350 checks &= ~PEER_OFFERED_PIPE;
1352 if ( checks & PEER_OFFERED_SIZE
1353 && pcre_exec(regex_SIZE, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1354 checks &= ~PEER_OFFERED_SIZE;
1361 /* Callback for emitting a BDAT data chunk header.
1363 If given a nonzero size, first flush any buffered SMTP commands
1364 then emit the command.
1366 Reap previous SMTP command responses if requested.
1367 Reap one SMTP command response if requested.
1369 Returns: OK or ERROR
1373 smtp_chunk_cmd_callback(int fd, transport_ctx * tctx,
1374 unsigned chunk_size, unsigned flags)
1376 smtp_transport_options_block * ob =
1377 (smtp_transport_options_block *)(tctx->tblock->options_block);
1380 uschar * buffer = tctx->buffer;
1383 /* Write SMTP chunk header command */
1386 if((cmd_count = smtp_write_command(tctx->outblock, FALSE, "BDAT %u%s\r\n",
1388 flags & tc_chunk_last ? " LAST" : "")
1389 ) < 0) return ERROR;
1391 prev_cmd_count = cmd_count += tctx->cmd_count;
1393 /* Reap responses for any previous, but not one we just emitted */
1397 if (tctx->pending_BDAT)
1400 if (flags & tc_reap_prev && prev_cmd_count > 0)
1403 switch(sync_responses(tctx->first_addr, tctx->tblock->rcpt_include_affixes,
1404 tctx->sync_addr, tctx->host, prev_cmd_count,
1405 ob->address_retry_include_sender,
1406 tctx->pending_MAIL, 0,
1408 ob->command_timeout,
1410 /*XXX buffer size! */
1412 case 1: /* 2xx (only) => OK */
1413 case 3: tctx->good_RCPT = TRUE; /* 2xx & 5xx => OK & progress made */
1414 case 2: *tctx->completed_address = TRUE; /* 5xx (only) => progress made */
1415 case 0: break; /* No 2xx or 5xx, but no probs */
1417 case -1: /* Timeout on RCPT */
1418 default: return ERROR; /* I/O error, or any MAIL/DATA error */
1421 if (!tctx->pending_BDAT)
1422 pipelining_active = FALSE;
1425 /* Reap response for the cmd we just emitted, or an outstanding BDAT */
1427 if (flags & tc_reap_one || tctx->pending_BDAT)
1429 /*XXX buffer size! */
1430 if (!smtp_read_response(tctx->inblock, buffer, 4096, '2',
1431 ob->command_timeout))
1433 if (errno == 0 && buffer[0] == '4')
1435 errno = ERRNO_DATA4XX; /*XXX does this actually get used? */
1436 tctx->first_addr->more_errno |=
1437 ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1442 tctx->pending_BDAT = FALSE;
1443 pipelining_active = FALSE;
1445 else if (chunk_size > 0)
1446 tctx->pending_BDAT = TRUE;
1449 tctx->cmd_count = cmd_count;
1455 /*************************************************
1456 * Deliver address list to given host *
1457 *************************************************/
1459 /* If continue_hostname is not null, we get here only when continuing to
1460 deliver down an existing channel. The channel was passed as the standard
1461 input. TLS is never active on a passed channel; the previous process always
1462 closes it down before passing the connection on.
1464 Otherwise, we have to make a connection to the remote host, and do the
1465 initial protocol exchange.
1467 When running as an MUA wrapper, if the sender or any recipient is rejected,
1468 temporarily or permanently, we force failure for all recipients.
1471 addrlist chain of potential addresses to deliver; only those whose
1472 transport_return field is set to PENDING_DEFER are currently
1473 being processed; others should be skipped - they have either
1474 been delivered to an earlier host or IP address, or been
1475 failed by one of them.
1476 host host to deliver to
1477 host_af AF_INET or AF_INET6
1478 port default TCP/IP port to use, in host byte order
1479 interface interface to bind to, or NULL
1480 tblock transport instance block
1481 message_defer set TRUE if yield is OK, but all addresses were deferred
1482 because of a non-recipient, non-host failure, that is, a
1483 4xx response to MAIL FROM, DATA, or ".". This is a defer
1484 that is specific to the message.
1485 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1486 a second attempt after TLS initialization fails
1488 Returns: OK - the connection was made and the delivery attempted;
1489 the result for each address is in its data block.
1490 DEFER - the connection could not be made, or something failed
1491 while setting up the SMTP session, or there was a
1492 non-message-specific error, such as a timeout.
1493 ERROR - a filter command is specified for this transport,
1494 and there was a problem setting it up; OR helo_data
1495 or add_headers or authenticated_sender is specified
1496 for this transport, and the string failed to expand
1500 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
1501 uschar *interface, transport_instance *tblock,
1502 BOOL *message_defer, BOOL suppress_tls)
1505 address_item *sync_addr;
1506 address_item *first_addr = addrlist;
1511 time_t start_delivery_time = time(NULL);
1512 smtp_transport_options_block *ob =
1513 (smtp_transport_options_block *)(tblock->options_block);
1514 BOOL lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
1515 BOOL smtps = strcmpic(ob->protocol, US"smtps") == 0;
1517 BOOL send_rset = TRUE;
1518 BOOL send_quit = TRUE;
1519 BOOL setting_up = TRUE;
1520 BOOL completed_address = FALSE;
1523 BOOL pass_message = FALSE;
1524 uschar peer_offered = 0; /*XXX should this be handed on cf. tls_offered, smtp_use_dsn ? */
1525 #ifndef DISABLE_PRDR
1529 BOOL utf8_needed = FALSE;
1531 BOOL dsn_all_lasthop = TRUE;
1532 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1534 BOOL dane_required = verify_check_given_host(&ob->hosts_require_dane, host) == OK;
1535 dns_answer tlsa_dnsa;
1537 smtp_inblock inblock;
1538 smtp_outblock outblock;
1539 int max_rcpt = tblock->max_addresses;
1540 uschar *igquotstr = US"";
1542 #ifdef EXPERIMENTAL_DSN_INFO
1543 uschar *smtp_greeting = NULL;
1544 uschar *helo_response = NULL;
1546 uschar *helo_data = NULL;
1548 uschar *message = NULL;
1549 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
1551 uschar buffer[4096];
1552 uschar inbuffer[4096];
1553 uschar outbuffer[4096];
1555 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
1557 *message_defer = FALSE;
1558 smtp_command = US"initial connection";
1559 if (max_rcpt == 0) max_rcpt = 999999;
1561 /* Set up the buffer for reading SMTP response packets. */
1563 inblock.buffer = inbuffer;
1564 inblock.buffersize = sizeof(inbuffer);
1565 inblock.ptr = inbuffer;
1566 inblock.ptrend = inbuffer;
1568 /* Set up the buffer for holding SMTP commands while pipelining */
1570 outblock.buffer = outbuffer;
1571 outblock.buffersize = sizeof(outbuffer);
1572 outblock.ptr = outbuffer;
1573 outblock.cmd_count = 0;
1574 outblock.authenticating = FALSE;
1576 /* Reset the parameters of a TLS session. */
1579 tls_out.cipher = NULL; /* the one we may use for this transport */
1580 tls_out.ourcert = NULL;
1581 tls_out.peercert = NULL;
1582 tls_out.peerdn = NULL;
1583 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1586 tls_out.ocsp = OCSP_NOT_REQ;
1588 /* Flip the legacy TLS-related variables over to the outbound set in case
1589 they're used in the context of the transport. Don't bother resetting
1590 afterward as we're in a subprocess. */
1592 tls_modify_variables(&tls_out);
1597 set_errno_nohost(addrlist, ERRNO_TLSFAILURE, US"TLS support not available",
1603 /* Make a connection to the host if this isn't a continued delivery, and handle
1604 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
1605 specially so they can be identified for retries. */
1607 if (continue_hostname == NULL)
1609 /* This puts port into host->port */
1610 inblock.sock = outblock.sock =
1611 smtp_connect(host, host_af, port, interface, ob->connect_timeout, tblock);
1613 if (inblock.sock < 0)
1615 set_errno_nohost(addrlist, (errno == ETIMEDOUT)? ERRNO_CONNECTTIMEOUT : errno,
1616 NULL, DEFER, FALSE);
1620 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1622 tls_out.dane_verified = FALSE;
1623 tls_out.tlsa_usage = 0;
1625 if (host->dnssec == DS_YES)
1628 || verify_check_given_host(&ob->hosts_try_dane, host) == OK
1630 switch (rc = tlsa_lookup(host, &tlsa_dnsa, dane_required))
1632 case OK: dane = TRUE; break;
1633 case FAIL_FORCED: break;
1634 default: set_errno_nohost(addrlist, ERRNO_DNSDEFER,
1635 string_sprintf("DANE error: tlsa lookup %s",
1636 rc == DEFER ? "DEFER" : "FAIL"),
1641 else if (dane_required)
1643 set_errno_nohost(addrlist, ERRNO_DNSDEFER,
1644 string_sprintf("DANE error: %s lookup not DNSSEC", host->name),
1650 ob->tls_tempfail_tryclear = FALSE;
1654 /* Expand the greeting message while waiting for the initial response. (Makes
1655 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1656 delayed till here so that $sending_interface and $sending_port are set. */
1658 helo_data = expand_string(ob->helo_data);
1662 uschar * errstr = NULL;
1663 if ((helo_data = string_domain_utf8_to_alabel(helo_data, &errstr)), errstr)
1665 errstr = string_sprintf("failed to expand helo_data: %s", errstr);
1666 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE);
1673 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1674 is nevertheless a reasonably clean way of programming this kind of logic,
1675 where you want to escape on any error. */
1679 BOOL good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
1680 '2', ob->command_timeout);
1681 #ifdef EXPERIMENTAL_DSN_INFO
1682 smtp_greeting = string_copy(buffer);
1684 if (!good_response) goto RESPONSE_FAILED;
1686 #ifndef DISABLE_EVENT
1689 lookup_dnssec_authenticated = host->dnssec==DS_YES ? US"yes"
1690 : host->dnssec==DS_NO ? US"no" : NULL;
1691 s = event_raise(tblock->event_action, US"smtp:connect", buffer);
1694 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL,
1695 string_sprintf("deferred by smtp:connect event expansion: %s", s),
1703 /* Now check if the helo_data expansion went well, and sign off cleanly if
1706 if (helo_data == NULL)
1708 uschar *message = string_sprintf("failed to expand helo_data: %s",
1709 expand_string_message);
1710 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1716 /** Debugging without sending a message
1717 addrlist->transport_return = DEFER;
1721 /* Errors that occur after this point follow an SMTP command, which is
1722 left in big_buffer by smtp_write_command() for use in error messages. */
1724 smtp_command = big_buffer;
1726 /* Tell the remote who we are...
1728 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1729 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1730 greeting is of this form. The assumption was that the far end supports it
1731 properly... but experience shows that there are some that give 5xx responses,
1732 even though the banner includes "ESMTP" (there's a bloody-minded one that
1733 says "ESMTP not spoken here"). Cope with that case.
1735 September 2000: Time has passed, and it seems reasonable now to always send
1736 EHLO at the start. It is also convenient to make the change while installing
1739 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1740 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1741 would be no way to send out the mails, so there is now a host list
1742 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1743 PIPELINING problem as well. Maybe it can also be useful to cure other
1744 problems with broken servers.
1746 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1747 Then somebody tried it with a Microsoft mailer... It seems that all other
1748 mailers use upper case for some reason (the RFC is quite clear about case
1749 independence) so, for peace of mind, I gave in. */
1751 esmtp = verify_check_given_host(&ob->hosts_avoid_esmtp, host) != OK;
1753 /* Alas; be careful, since this goto is not an error-out, so conceivably
1754 we might set data between here and the target which we assume to exist
1755 and be usable. I can see this coming back to bite us. */
1760 suppress_tls = FALSE;
1761 ob->tls_tempfail_tryclear = FALSE;
1762 smtp_command = US"SSL-on-connect";
1769 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1770 lmtp? "LHLO" : "EHLO", helo_data) < 0)
1772 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1773 ob->command_timeout))
1775 if (errno != 0 || buffer[0] == 0 || lmtp)
1777 #ifdef EXPERIMENTAL_DSN_INFO
1778 helo_response = string_copy(buffer);
1780 goto RESPONSE_FAILED;
1784 #ifdef EXPERIMENTAL_DSN_INFO
1785 helo_response = string_copy(buffer);
1791 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1798 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1800 good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
1801 '2', ob->command_timeout);
1802 #ifdef EXPERIMENTAL_DSN_INFO
1803 helo_response = string_copy(buffer);
1805 if (!good_response) goto RESPONSE_FAILED;
1809 peer_offered = ehlo_response(buffer, Ustrlen(buffer),
1810 PEER_OFFERED_TLS /* others checked later */
1813 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1816 tls_offered = !!(peer_offered & PEER_OFFERED_TLS);
1820 /* For continuing deliveries down the same channel, the socket is the standard
1821 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1822 below). Set up the pointer to where subsequent commands will be left, for
1823 error messages. Note that smtp_use_size and smtp_use_pipelining will have been
1824 set from the command line if they were set in the process that passed the
1827 /*XXX continue case needs to propagate DSN_INFO, prob. in deliver.c
1828 as the contine goes via transport_pass_socket() and doublefork and exec.
1829 It does not wait. Unclear how we keep separate host's responses
1830 separate - we could match up by host ip+port as a bodge. */
1834 inblock.sock = outblock.sock = fileno(stdin);
1835 smtp_command = big_buffer;
1836 host->port = port; /* Record the port that was used */
1839 /* If TLS is available on this connection, whether continued or not, attempt to
1840 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1841 send another EHLO - the server may give a different answer in secure mode. We
1842 use a separate buffer for reading the response to STARTTLS so that if it is
1843 negative, the original EHLO data is available for subsequent analysis, should
1844 the client not be required to use TLS. If the response is bad, copy the buffer
1845 for error analysis. */
1850 && verify_check_given_host(&ob->hosts_avoid_tls, host) != OK)
1852 uschar buffer2[4096];
1853 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1856 /* If there is an I/O error, transmission of this message is deferred. If
1857 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1858 false, we also defer. However, if there is a temporary rejection of STARTTLS
1859 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1860 STARTTLS, we carry on. This means we will try to send the message in clear,
1861 unless the host is in hosts_require_tls (tested below). */
1863 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1864 ob->command_timeout))
1868 || (buffer2[0] == '4' && !ob->tls_tempfail_tryclear)
1871 Ustrncpy(buffer, buffer2, sizeof(buffer));
1872 goto RESPONSE_FAILED;
1876 /* STARTTLS accepted: try to negotiate a TLS session. */
1881 int rc = tls_client_start(inblock.sock, host, addrlist, tblock
1882 # ifdef EXPERIMENTAL_DANE
1883 , dane ? &tlsa_dnsa : NULL
1887 /* TLS negotiation failed; give an error. From outside, this function may
1888 be called again to try in clear on a new connection, if the options permit
1889 it for this host. */
1893 # ifdef EXPERIMENTAL_DANE
1894 if (rc == DEFER && dane)
1896 log_write(0, LOG_MAIN,
1897 "DANE attempt failed; no TLS connection to %s [%s]",
1898 host->name, host->address);
1902 save_errno = ERRNO_TLSFAILURE;
1903 message = US"failure while setting up TLS session";
1908 /* TLS session is set up */
1910 for (addr = addrlist; addr; addr = addr->next)
1911 if (addr->transport_return == PENDING_DEFER)
1913 addr->cipher = tls_out.cipher;
1914 addr->ourcert = tls_out.ourcert;
1915 addr->peercert = tls_out.peercert;
1916 addr->peerdn = tls_out.peerdn;
1917 addr->ocsp = tls_out.ocsp;
1922 /* if smtps, we'll have smtp_command set to something else; always safe to
1924 smtp_command = big_buffer;
1926 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1927 helo_data is null, we are dealing with a connection that was passed from
1928 another process, and so we won't have expanded helo_data above. We have to
1929 expand it here. $sending_ip_address and $sending_port are set up right at the
1930 start of the Exim process (in exim.c). */
1932 if (tls_out.active >= 0)
1937 if (helo_data == NULL)
1939 helo_data = expand_string(ob->helo_data);
1940 if (helo_data == NULL)
1942 uschar *message = string_sprintf("failed to expand helo_data: %s",
1943 expand_string_message);
1944 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1950 /* For SMTPS we need to wait for the initial OK response. */
1953 good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
1954 '2', ob->command_timeout);
1955 #ifdef EXPERIMENTAL_DSN_INFO
1956 smtp_greeting = string_copy(buffer);
1958 if (!good_response) goto RESPONSE_FAILED;
1962 greeting_cmd = "EHLO";
1965 greeting_cmd = "HELO";
1967 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1970 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1971 lmtp? "LHLO" : greeting_cmd, helo_data) < 0)
1973 good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
1974 '2', ob->command_timeout);
1975 #ifdef EXPERIMENTAL_DSN_INFO
1976 helo_response = string_copy(buffer);
1978 if (!good_response) goto RESPONSE_FAILED;
1981 /* If the host is required to use a secure channel, ensure that we
1985 # ifdef EXPERIMENTAL_DANE
1988 || verify_check_given_host(&ob->hosts_require_tls, host) == OK
1991 save_errno = ERRNO_TLSREQUIRED;
1992 message = string_sprintf("a TLS session is required, but %s",
1993 tls_offered ? "an attempt to start TLS failed"
1994 : "the server did not offer TLS support");
1997 #endif /*SUPPORT_TLS*/
1999 /* If TLS is active, we have just started it up and re-done the EHLO command,
2000 so its response needs to be analyzed. If TLS is not active and this is a
2001 continued session down a previously-used socket, we haven't just done EHLO, so
2004 if (continue_hostname == NULL
2006 || tls_out.active >= 0
2011 peer_offered = ehlo_response(buffer, Ustrlen(buffer),
2013 | (lmtp && ob->lmtp_ignore_quota ? PEER_OFFERED_IGNQ : 0)
2014 | PEER_OFFERED_CHUNKING
2017 | (addrlist->prop.utf8_msg ? PEER_OFFERED_UTF8 : 0)
2018 /*XXX if we hand peercaps on to continued-conn processes,
2019 must not depend on this addr */
2023 | (ob->size_addition >= 0 ? PEER_OFFERED_SIZE : 0)
2026 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
2027 lmtp_ignore_quota option was set. */
2029 igquotstr = peer_offered & PEER_OFFERED_IGNQ ? US" IGNOREQUOTA" : US"";
2031 /* If the response to EHLO specified support for the SIZE parameter, note
2032 this, provided size_addition is non-negative. */
2034 smtp_use_size = !!(peer_offered & PEER_OFFERED_SIZE);
2036 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
2037 the current host, esmtp will be false, so PIPELINING can never be used. If
2038 the current host matches hosts_avoid_pipelining, don't do it. */
2040 smtp_use_pipelining = peer_offered & PEER_OFFERED_PIPE
2041 && verify_check_given_host(&ob->hosts_avoid_pipelining, host) != OK;
2043 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
2044 smtp_use_pipelining ? "" : "not ");
2046 if ( peer_offered & PEER_OFFERED_CHUNKING
2047 && verify_check_given_host(&ob->hosts_try_chunking, host) != OK)
2048 peer_offered &= ~PEER_OFFERED_CHUNKING;
2050 if (peer_offered & PEER_OFFERED_CHUNKING)
2051 {DEBUG(D_transport) debug_printf("CHUNKING usable\n");}
2053 #ifndef DISABLE_PRDR
2054 if ( peer_offered & PEER_OFFERED_PRDR
2055 && verify_check_given_host(&ob->hosts_try_prdr, host) != OK)
2056 peer_offered &= ~PEER_OFFERED_PRDR;
2058 if (peer_offered & PEER_OFFERED_PRDR)
2059 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
2062 /* Note if the server supports DSN */
2063 smtp_use_dsn = !!(peer_offered & PEER_OFFERED_DSN);
2064 DEBUG(D_transport) debug_printf("%susing DSN\n", smtp_use_dsn ? "" : "not ");
2066 /* Note if the response to EHLO specifies support for the AUTH extension.
2067 If it has, check that this host is one we want to authenticate to, and do
2068 the business. The host name and address must be available when the
2069 authenticator's client driver is running. */
2071 switch (yield = smtp_auth(buffer, sizeof(buffer), addrlist, host,
2072 ob, esmtp, &inblock, &outblock))
2074 default: goto SEND_QUIT;
2076 case FAIL_SEND: goto SEND_FAILED;
2077 case FAIL: goto RESPONSE_FAILED;
2080 pipelining_active = smtp_use_pipelining;
2082 /* The setting up of the SMTP call is now complete. Any subsequent errors are
2083 message-specific. */
2088 if (addrlist->prop.utf8_msg)
2090 utf8_needed = !addrlist->prop.utf8_downcvt
2091 && !addrlist->prop.utf8_downcvt_maybe;
2092 DEBUG(D_transport) if (!utf8_needed) debug_printf("utf8: %s downconvert\n",
2093 addrlist->prop.utf8_downcvt ? "mandatory" : "optional");
2096 /* If this is an international message we need the host to speak SMTPUTF8 */
2097 if (utf8_needed && !(peer_offered & PEER_OFFERED_UTF8))
2099 errno = ERRNO_UTF8_FWD;
2100 goto RESPONSE_FAILED;
2104 /* If there is a filter command specified for this transport, we can now
2105 set it up. This cannot be done until the identify of the host is known. */
2107 if (tblock->filter_command != NULL)
2111 sprintf(CS buffer, "%.50s transport", tblock->name);
2112 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
2113 TRUE, DEFER, addrlist, buffer, NULL);
2114 transport_filter_timeout = tblock->filter_timeout;
2116 /* On failure, copy the error to all addresses, abandon the SMTP call, and
2121 set_errno_nohost(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
2129 /* For messages that have more than the maximum number of envelope recipients,
2130 we want to send several transactions down the same SMTP connection. (See
2131 comments in deliver.c as to how this reconciles, heuristically, with
2132 remote_max_parallel.) This optimization was added to Exim after the following
2133 code was already working. The simplest way to put it in without disturbing the
2134 code was to use a goto to jump back to this point when there is another
2135 transaction to handle. */
2138 sync_addr = first_addr;
2142 completed_address = FALSE;
2145 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
2146 qualification, send it, adding something to the message size to allow for
2147 imprecision and things that get added en route. Exim keeps the number of lines
2148 in a message, so we can give an accurate value for the original message, but we
2149 need some additional to handle added headers. (Double "." characters don't get
2150 included in the count.) */
2157 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
2161 #ifndef DISABLE_PRDR
2162 prdr_active = FALSE;
2163 if (peer_offered & PEER_OFFERED_PRDR)
2164 for (addr = first_addr; addr; addr = addr->next)
2165 if (addr->transport_return == PENDING_DEFER)
2167 for (addr = addr->next; addr; addr = addr->next)
2168 if (addr->transport_return == PENDING_DEFER)
2169 { /* at least two recipients to send */
2171 sprintf(CS p, " PRDR"); p += 5;
2179 if ( addrlist->prop.utf8_msg
2180 && !addrlist->prop.utf8_downcvt
2181 && peer_offered & PEER_OFFERED_UTF8
2183 sprintf(CS p, " SMTPUTF8"), p += 9;
2186 /* check if all addresses have lasthop flag */
2187 /* do not send RET and ENVID if true */
2188 for (dsn_all_lasthop = TRUE, addr = first_addr;
2189 address_count < max_rcpt && addr != NULL;
2191 if ((addr->dsn_flags & rf_dsnlasthop) != 1)
2193 dsn_all_lasthop = FALSE;
2197 /* Add any DSN flags to the mail command */
2199 if (smtp_use_dsn && !dsn_all_lasthop)
2201 if (dsn_ret == dsn_ret_hdrs)
2202 { Ustrcpy(p, " RET=HDRS"); p += 9; }
2203 else if (dsn_ret == dsn_ret_full)
2204 { Ustrcpy(p, " RET=FULL"); p += 9; }
2208 string_format(p, sizeof(buffer) - (p-buffer), " ENVID=%s", dsn_envid);
2213 /* If an authenticated_sender override has been specified for this transport
2214 instance, expand it. If the expansion is forced to fail, and there was already
2215 an authenticated_sender for this message, the original value will be used.
2216 Other expansion failures are serious. An empty result is ignored, but there is
2217 otherwise no check - this feature is expected to be used with LMTP and other
2218 cases where non-standard addresses (e.g. without domains) might be required. */
2220 if (smtp_mail_auth_str(p, sizeof(buffer) - (p-buffer), addrlist, ob))
2226 /* From here until we send the DATA command, we can make use of PIPELINING
2227 if the server host supports it. The code has to be able to check the responses
2228 at any point, for when the buffer fills up, so we write it totally generally.
2229 When PIPELINING is off, each command written reports that it has flushed the
2232 pending_MAIL = TRUE; /* The block starts with MAIL */
2235 uschar * s = return_path;
2237 uschar * errstr = NULL;
2239 /* If we must downconvert, do the from-address here. Remember we had to
2240 for the to-addresses (done below), and also (ugly) for re-doing when building
2241 the delivery log line. */
2243 if ( addrlist->prop.utf8_msg
2244 && (addrlist->prop.utf8_downcvt || !(peer_offered & PEER_OFFERED_UTF8))
2247 if (s = string_address_utf8_to_alabel(return_path, &errstr), errstr)
2249 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE);
2253 setflag(addrlist, af_utf8_downcvt);
2257 rc = smtp_write_command(&outblock, smtp_use_pipelining,
2258 "MAIL FROM:<%s>%s\r\n", s, buffer);
2261 mail_command = string_copy(big_buffer); /* Save for later error message */
2265 case -1: /* Transmission error */
2268 case +1: /* Block was sent */
2269 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2270 ob->command_timeout))
2272 if (errno == 0 && buffer[0] == '4')
2274 errno = ERRNO_MAIL4XX;
2275 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2277 goto RESPONSE_FAILED;
2279 pending_MAIL = FALSE;
2283 /* Pass over all the relevant recipient addresses for this host, which are the
2284 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
2285 several before we have to read the responses for those seen so far. This
2286 checking is done by a subroutine because it also needs to be done at the end.
2287 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
2288 the next one if not all are sent.
2290 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
2291 last address because we want to abort if any recipients have any kind of
2292 problem, temporary or permanent. We know that all recipient addresses will have
2293 the PENDING_DEFER status, because only one attempt is ever made, and we know
2294 that max_rcpt will be large, so all addresses will be done at once. */
2296 for (addr = first_addr;
2297 addr && address_count < max_rcpt;
2304 addr->dsn_aware = smtp_use_dsn ? dsn_support_yes : dsn_support_no;
2306 if (addr->transport_return != PENDING_DEFER) continue;
2309 no_flush = smtp_use_pipelining && (!mua_wrapper || addr->next);
2311 /* Add any DSN flags to the rcpt command and add to the sent string */
2316 if (smtp_use_dsn && !(addr->dsn_flags & rf_dsnlasthop))
2318 if ((addr->dsn_flags & rf_dsnflags) != 0)
2322 Ustrcpy(p, " NOTIFY=");
2324 for (i = 0; i < 4; i++)
2325 if ((addr->dsn_flags & rf_list[i]) != 0)
2327 if (!first) *p++ = ',';
2329 Ustrcpy(p, rf_names[i]);
2334 if (addr->dsn_orcpt)
2336 string_format(p, sizeof(buffer) - (p-buffer), " ORCPT=%s",
2342 /* Now send the RCPT command, and process outstanding responses when
2343 necessary. After a timeout on RCPT, we just end the function, leaving the
2344 yield as OK, because this error can often mean that there is a problem with
2345 just one address, so we don't want to delay the host. */
2347 rcpt_addr = transport_rcpt_address(addr, tblock->rcpt_include_affixes);
2351 uschar * dummy_errstr;
2352 if ( testflag(addrlist, af_utf8_downcvt)
2353 && (rcpt_addr = string_address_utf8_to_alabel(rcpt_addr, &dummy_errstr),
2357 errno = ERRNO_EXPANDFAIL;
2363 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s%s\r\n",
2364 rcpt_addr, igquotstr, buffer);
2366 if (count < 0) goto SEND_FAILED;
2369 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
2370 &sync_addr, host, count, ob->address_retry_include_sender,
2371 pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
2374 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2375 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2378 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2379 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2380 case 0: /* No 2xx or 5xx, but no probs */
2383 case -1: goto END_OFF; /* Timeout on RCPT */
2384 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
2386 pending_MAIL = FALSE; /* Dealt with MAIL */
2388 } /* Loop for next address */
2390 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
2391 permanently or temporarily. We should have flushed and synced after the last
2396 address_item *badaddr;
2397 for (badaddr = first_addr; badaddr; badaddr = badaddr->next)
2398 if (badaddr->transport_return != PENDING_OK)
2400 /*XXX could we find a better errno than 0 here? */
2401 set_errno_nohost(addrlist, 0, badaddr->message, FAIL,
2402 testflag(badaddr, af_pass_message));
2408 /* If ok is TRUE, we know we have got at least one good recipient, and must now
2409 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
2410 have a good recipient buffered up if we are pipelining. We don't want to waste
2411 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
2412 are pipelining. The responses are all handled by sync_responses().
2413 If using CHUNKING, do not send a BDAT until we know how big a chunk we want
2416 if ( !(peer_offered & PEER_OFFERED_CHUNKING)
2417 && (ok || (smtp_use_pipelining && !mua_wrapper)))
2419 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
2421 if (count < 0) goto SEND_FAILED;
2422 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
2423 host, count, ob->address_retry_include_sender, pending_MAIL,
2424 ok ? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
2426 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2427 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2430 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2431 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2432 case 0: break; /* No 2xx or 5xx, but no probs */
2434 case -1: goto END_OFF; /* Timeout on RCPT */
2435 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2437 pipelining_active = FALSE;
2440 /* If there were no good recipients (but otherwise there have been no
2441 problems), just set ok TRUE, since we have handled address-specific errors
2442 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
2443 for handling the SMTP dot-handling protocol, flagging to apply to headers as
2444 well as body. Set the appropriate timeout value to be used for each chunk.
2445 (Haven't been able to make it work using select() for writing yet.) */
2447 if (!(peer_offered & PEER_OFFERED_CHUNKING) && !ok)
2449 /* Save the first address of the next batch. */
2456 transport_ctx tctx = {
2459 US".", US"..", /* Escaping strings */
2460 topt_use_crlf | topt_escape_headers
2461 | (tblock->body_only ? topt_no_headers : 0)
2462 | (tblock->headers_only ? topt_no_body : 0)
2463 | (tblock->return_path_add ? topt_add_return_path : 0)
2464 | (tblock->delivery_date_add ? topt_add_delivery_date : 0)
2465 | (tblock->envelope_to_add ? topt_add_envelope_to : 0),
2468 /* If using CHUNKING we need a callback from the generic transport
2469 support to us, for the sending of BDAT smtp commands and the reaping
2470 of responses. The callback needs a whole bunch of state so set up
2471 a transport-context structure to be passed around. */
2473 if (peer_offered & PEER_OFFERED_CHUNKING)
2475 tctx.check_string = tctx.escape_string = NULL;
2476 tctx.options |= topt_use_bdat;
2477 tctx.chunk_cb = smtp_chunk_cmd_callback;
2478 tctx.inblock = &inblock;
2479 tctx.outblock = &outblock;
2481 tctx.first_addr = first_addr;
2482 tctx.sync_addr = &sync_addr;
2483 tctx.pending_MAIL = pending_MAIL;
2484 tctx.pending_BDAT = FALSE;
2485 tctx.good_RCPT = ok;
2486 tctx.completed_address = &completed_address;
2488 tctx.buffer = buffer;
2491 tctx.options |= topt_end_dot;
2493 /* Save the first address of the next batch. */
2496 /* Responses from CHUNKING commands go in buffer. Otherwise,
2497 there has not been a response. */
2501 sigalrm_seen = FALSE;
2502 transport_write_timeout = ob->data_timeout;
2503 smtp_command = US"sending data block"; /* For error messages */
2504 DEBUG(D_transport|D_v)
2505 if (peer_offered & PEER_OFFERED_CHUNKING)
2506 debug_printf(" will write message using CHUNKING\n");
2508 debug_printf(" SMTP>> writing message and terminating \".\"\n");
2509 transport_count = 0;
2511 #ifndef DISABLE_DKIM
2512 ok = dkim_transport_write_message(inblock.sock, &tctx, &ob->dkim);
2514 ok = transport_write_message(inblock.sock, &tctx, 0);
2517 /* transport_write_message() uses write() because it is called from other
2518 places to write to non-sockets. This means that under some OS (e.g. Solaris)
2519 it can exit with "Broken pipe" as its error. This really means that the
2520 socket got closed at the far end. */
2522 transport_write_timeout = 0; /* for subsequent transports */
2524 /* Failure can either be some kind of I/O disaster (including timeout),
2525 or the failure of a transport filter or the expansion of added headers.
2526 Or, when CHUNKING, it can be a protocol-detected failure. */
2529 goto RESPONSE_FAILED;
2531 /* We used to send the terminating "." explicitly here, but because of
2532 buffering effects at both ends of TCP/IP connections, you don't gain
2533 anything by keeping it separate, so it might as well go in the final
2534 data buffer for efficiency. This is now done by setting the topt_end_dot
2537 smtp_command = US"end of data";
2539 if (peer_offered & PEER_OFFERED_CHUNKING && tctx.cmd_count > 1)
2541 /* Reap any outstanding MAIL & RCPT commands, but not a DATA-go-ahead */
2542 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
2543 host, tctx.cmd_count-1, ob->address_retry_include_sender,
2545 &inblock, ob->command_timeout, buffer, sizeof(buffer)))
2547 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2548 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2551 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2552 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2553 case 0: break; /* No 2xx or 5xx, but no probs */
2555 case -1: goto END_OFF; /* Timeout on RCPT */
2556 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2560 #ifndef DISABLE_PRDR
2561 /* For PRDR we optionally get a partial-responses warning
2562 * followed by the individual responses, before going on with
2563 * the overall response. If we don't get the warning then deal
2564 * with per non-PRDR. */
2567 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '3',
2569 if (!ok && errno == 0) switch(buffer[0])
2571 case '2': prdr_active = FALSE;
2574 case '4': errno = ERRNO_DATA4XX;
2575 addrlist->more_errno |=
2576 ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2583 /* For non-PRDR SMTP, we now read a single response that applies to the
2584 whole message. If it is OK, then all the addresses have been delivered. */
2588 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2590 if (!ok && errno == 0 && buffer[0] == '4')
2592 errno = ERRNO_DATA4XX;
2593 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2597 /* For LMTP, we get back a response for every RCPT command that we sent;
2598 some may be accepted and some rejected. For those that get a response, their
2599 status is fixed; any that are accepted have been handed over, even if later
2600 responses crash - at least, that's how I read RFC 2033.
2602 If all went well, mark the recipient addresses as completed, record which
2603 host/IPaddress they were delivered to, and cut out RSET when sending another
2604 message down the same channel. Write the completed addresses to the journal
2605 now so that they are recorded in case there is a crash of hardware or
2606 software before the spool gets updated. Also record the final SMTP
2607 confirmation if needed (for SMTP only). */
2612 int delivery_time = (int)(time(NULL) - start_delivery_time);
2614 uschar *conf = NULL;
2617 pipelining_active = FALSE;
2619 /* Set up confirmation if needed - applies only to SMTP */
2622 #ifdef DISABLE_EVENT
2623 LOGGING(smtp_confirmation) &&
2628 const uschar *s = string_printing(buffer);
2629 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
2630 conf = (s == buffer)? (uschar *)string_copy(s) : US s;
2633 /* Process all transported addresses - for LMTP or PRDR, read a status for
2636 for (addr = addrlist; addr != first_addr; addr = addr->next)
2638 if (addr->transport_return != PENDING_OK) continue;
2640 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
2641 remaining addresses. Otherwise, it's a return code for just the one
2642 address. For temporary errors, add a retry item for the address so that
2643 it doesn't get tried again too soon. */
2645 #ifndef DISABLE_PRDR
2646 if (lmtp || prdr_active)
2651 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2654 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
2655 addr->message = string_sprintf(
2656 #ifndef DISABLE_PRDR
2657 "%s error after %s: %s", prdr_active ? "PRDR":"LMTP",
2659 "LMTP error after %s: %s",
2661 big_buffer, string_printing(buffer));
2662 setflag(addr, af_pass_message); /* Allow message to go to user */
2663 if (buffer[0] == '5')
2664 addr->transport_return = FAIL;
2667 errno = ERRNO_DATA4XX;
2668 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2669 addr->transport_return = DEFER;
2670 #ifndef DISABLE_PRDR
2673 retry_add_item(addr, addr->address_retry_key, 0);
2677 completed_address = TRUE; /* NOW we can set this flag */
2678 if (LOGGING(smtp_confirmation))
2680 const uschar *s = string_printing(buffer);
2681 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
2682 conf = (s == buffer)? (uschar *)string_copy(s) : US s;
2686 /* SMTP, or success return from LMTP for this address. Pass back the
2687 actual host that was used. */
2689 addr->transport_return = OK;
2690 addr->more_errno = delivery_time;
2691 addr->host_used = host;
2692 addr->special_action = flag;
2693 addr->message = conf;
2694 #ifndef DISABLE_PRDR
2695 if (prdr_active) addr->flags |= af_prdr_used;
2699 #ifndef DISABLE_PRDR
2703 /* Update the journal. For homonymic addresses, use the base address plus
2704 the transport name. See lots of comments in deliver.c about the reasons
2705 for the complications when homonyms are involved. Just carry on after
2706 write error, as it may prove possible to update the spool file later. */
2708 if (testflag(addr, af_homonym))
2709 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2711 sprintf(CS buffer, "%.500s\n", addr->unique);
2713 DEBUG(D_deliver) debug_printf("journalling %s\n", buffer);
2714 len = Ustrlen(CS buffer);
2715 if (write(journal_fd, buffer, len) != len)
2716 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2717 "%s: %s", buffer, strerror(errno));
2721 #ifndef DISABLE_PRDR
2724 /* PRDR - get the final, overall response. For any non-success
2725 upgrade all the address statuses. */
2726 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2730 if(errno == 0 && buffer[0] == '4')
2732 errno = ERRNO_DATA4XX;
2733 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2735 for (addr = addrlist; addr != first_addr; addr = addr->next)
2736 if (buffer[0] == '5' || addr->transport_return == OK)
2737 addr->transport_return = PENDING_OK; /* allow set_errno action */
2738 goto RESPONSE_FAILED;
2741 /* Update the journal, or setup retry. */
2742 for (addr = addrlist; addr != first_addr; addr = addr->next)
2743 if (addr->transport_return == OK)
2745 if (testflag(addr, af_homonym))
2746 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2748 sprintf(CS buffer, "%.500s\n", addr->unique);
2750 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s\n", buffer);
2751 len = Ustrlen(CS buffer);
2752 if (write(journal_fd, buffer, len) != len)
2753 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2754 "%s: %s", buffer, strerror(errno));
2756 else if (addr->transport_return == DEFER)
2757 retry_add_item(addr, addr->address_retry_key, -2);
2761 /* Ensure the journal file is pushed out to disk. */
2763 if (EXIMfsync(journal_fd) < 0)
2764 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
2770 /* Handle general (not specific to one address) failures here. The value of ok
2771 is used to skip over this code on the falling through case. A timeout causes a
2772 deferral. Other errors may defer or fail according to the response code, and
2773 may set up a special errno value, e.g. after connection chopped, which is
2774 assumed if errno == 0 and there is no text in the buffer. If control reaches
2775 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
2776 the problem is not related to this specific message. */
2781 uschar * set_message;
2787 send_quit = check_response(host, &save_errno, addrlist->more_errno,
2788 buffer, &code, &message, &pass_message);
2796 message = US string_sprintf("send() to %s [%s] failed: %s",
2797 host->name, host->address, strerror(save_errno));
2802 /* This label is jumped to directly when a TLS negotiation has failed,
2803 or was not done for a host for which it is required. Values will be set
2804 in message and save_errno, and setting_up will always be true. Treat as
2805 a temporary error. */
2812 /* If the failure happened while setting up the call, see if the failure was
2813 a 5xx response (this will either be on connection, or following HELO - a 5xx
2814 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
2815 never going to accept them. For other errors during setting up (timeouts or
2816 whatever), defer all addresses, and yield DEFER, so that the host is not
2817 tried again for a while. */
2820 ok = FALSE; /* For when reached by GOTO */
2821 set_message = message;
2828 yield = set_rc = DEFER;
2831 /* We want to handle timeouts after MAIL or "." and loss of connection after
2832 "." specially. They can indicate a problem with the sender address or with
2833 the contents of the message rather than a real error on the connection. These
2834 cases are treated in the same way as a 4xx response. This next bit of code
2835 does the classification. */
2844 case ERRNO_UTF8_FWD:
2851 message_error = TRUE;
2855 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
2856 Ustrncmp(smtp_command,"end ",4) == 0;
2859 case ERRNO_SMTPCLOSED:
2860 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
2864 message_error = FALSE;
2868 /* Handle the cases that are treated as message errors. These are:
2870 (a) negative response or timeout after MAIL
2871 (b) negative response after DATA
2872 (c) negative response or timeout or dropped connection after "."
2873 (d) utf8 support required and not offered
2875 It won't be a negative response or timeout after RCPT, as that is dealt
2876 with separately above. The action in all cases is to set an appropriate
2877 error code for all the addresses, but to leave yield set to OK because the
2878 host itself has not failed. Of course, it might in practice have failed
2879 when we've had a timeout, but if so, we'll discover that at the next
2880 delivery attempt. For a temporary error, set the message_defer flag, and
2881 write to the logs for information if this is not the last host. The error
2882 for the last host will be logged as part of the address's log line. */
2886 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
2888 /* If there's an errno, the message contains just the identity of
2893 else /* Anything other than 5 is treated as temporary */
2897 message = US string_sprintf("%s: %s", message, strerror(save_errno));
2898 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
2899 msglog_line(host, message);
2900 *message_defer = TRUE;
2904 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
2905 ".", or some other transportation error. We defer all addresses and yield
2906 DEFER, except for the case of failed add_headers expansion, or a transport
2907 filter failure, when the yield should be ERROR, to stop it trying other
2913 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
2914 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
2918 set_errno(addrlist, save_errno, set_message, set_rc, pass_message, host
2919 #ifdef EXPERIMENTAL_DSN_INFO
2920 , smtp_greeting, helo_response
2926 /* If all has gone well, send_quit will be set TRUE, implying we can end the
2927 SMTP session tidily. However, if there were too many addresses to send in one
2928 message (indicated by first_addr being non-NULL) we want to carry on with the
2929 rest of them. Also, it is desirable to send more than one message down the SMTP
2930 connection if there are several waiting, provided we haven't already sent so
2931 many as to hit the configured limit. The function transport_check_waiting looks
2932 for a waiting message and returns its id. Then transport_pass_socket tries to
2933 set up a continued delivery by passing the socket on to another process. The
2934 variable send_rset is FALSE if a message has just been successfully transfered.
2936 If we are already sending down a continued channel, there may be further
2937 addresses not yet delivered that are aimed at the same host, but which have not
2938 been passed in this run of the transport. In this case, continue_more will be
2939 true, and all we should do is send RSET if necessary, and return, leaving the
2942 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
2943 do not want to continue with other messages down the same channel, because that
2944 can lead to looping between two or more messages, all with the same,
2945 temporarily failing address(es). [The retry information isn't updated yet, so
2946 new processes keep on trying.] We probably also don't want to try more of this
2947 message's addresses either.
2949 If we have started a TLS session, we have to end it before passing the
2950 connection to a new process. However, not all servers can handle this (Exim
2951 can), so we do not pass such a connection on if the host matches
2952 hosts_nopass_tls. */
2955 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
2956 "yield=%d first_address is %sNULL\n", ok, send_quit, send_rset,
2957 continue_more, yield, (first_addr == NULL)? "":"not ");
2959 if (completed_address && ok && send_quit)
2962 smtp_compare_t t_compare;
2964 t_compare.tblock = tblock;
2965 t_compare.current_sender_address = sender_address;
2967 if ( first_addr != NULL
2969 || ( ( tls_out.active < 0
2970 || verify_check_given_host(&ob->hosts_nopass_tls, host) != OK
2973 transport_check_waiting(tblock->name, host->name,
2974 tblock->connection_max_messages, new_message_id, &more,
2975 (oicf)smtp_are_same_identities, (void*)&t_compare)
2983 if (! (ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
2985 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
2986 host->address, strerror(save_errno));
2989 else if (! (ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2990 ob->command_timeout)))
2993 send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
2997 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
2998 host->name, host->address, msg);
3003 /* Either RSET was not needed, or it succeeded */
3007 if (first_addr != NULL) /* More addresses still to be sent */
3008 { /* in this run of the transport */
3009 continue_sequence++; /* Causes * in logging */
3012 if (continue_more) return yield; /* More addresses for another run */
3014 /* Pass the socket to a new Exim process. Before doing so, we must shut
3015 down TLS. Not all MTAs allow for the continuation of the SMTP session
3016 when TLS is shut down. We test for this by sending a new EHLO. If we
3017 don't get a good response, we don't attempt to pass the socket on. */
3020 if (tls_out.active >= 0)
3022 tls_close(FALSE, TRUE);
3026 ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
3027 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
3028 ob->command_timeout);
3032 /* If the socket is successfully passed, we musn't send QUIT (or
3033 indeed anything!) from here. */
3035 /*XXX DSN_INFO: assume likely to do new HELO; but for greet we'll want to
3036 propagate it from the initial
3038 if (ok && transport_pass_socket(tblock->name, host->name, host->address,
3039 new_message_id, inblock.sock))
3045 /* If RSET failed and there are addresses left, they get deferred. */
3047 else set_errno(first_addr, errno, msg, DEFER, FALSE, host
3048 #ifdef EXPERIMENTAL_DSN_INFO
3049 , smtp_greeting, helo_response
3055 /* End off tidily with QUIT unless the connection has died or the socket has
3056 been passed to another process. There has been discussion on the net about what
3057 to do after sending QUIT. The wording of the RFC suggests that it is necessary
3058 to wait for a response, but on the other hand, there isn't anything one can do
3059 with an error response, other than log it. Exim used to do that. However,
3060 further discussion suggested that it is positively advantageous not to wait for
3061 the response, but to close the session immediately. This is supposed to move
3062 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
3063 load from the server. (Hosts that are both servers and clients may not see much
3064 difference, of course.) Further discussion indicated that this was safe to do
3065 on Unix systems which have decent implementations of TCP/IP that leave the
3066 connection around for a while (TIME_WAIT) after the application has gone away.
3067 This enables the response sent by the server to be properly ACKed rather than
3068 timed out, as can happen on broken TCP/IP implementations on other OS.
3070 This change is being made on 31-Jul-98. After over a year of trouble-free
3071 operation, the old commented-out code was removed on 17-Sep-99. */
3074 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
3079 tls_close(FALSE, TRUE);
3082 /* Close the socket, and return the appropriate value, first setting
3083 works because the NULL setting is passed back to the calling process, and
3084 remote_max_parallel is forced to 1 when delivering over an existing connection,
3086 If all went well and continue_more is set, we shouldn't actually get here if
3087 there are further addresses, as the return above will be taken. However,
3088 writing RSET might have failed, or there may be other addresses whose hosts are
3089 specified in the transports, and therefore not visible at top level, in which
3090 case continue_more won't get set. */
3092 HDEBUG(D_transport|D_acl|D_v) debug_printf(" SMTP(close)>>\n");
3093 (void)close(inblock.sock);
3095 #ifndef DISABLE_EVENT
3096 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
3099 continue_transport = NULL;
3100 continue_hostname = NULL;
3107 /*************************************************
3108 * Closedown entry point *
3109 *************************************************/
3111 /* This function is called when exim is passed an open smtp channel
3112 from another incarnation, but the message which it has been asked
3113 to deliver no longer exists. The channel is on stdin.
3115 We might do fancy things like looking for another message to send down
3116 the channel, but if the one we sought has gone, it has probably been
3117 delivered by some other process that itself will seek further messages,
3118 so just close down our connection.
3120 Argument: pointer to the transport instance block
3125 smtp_transport_closedown(transport_instance *tblock)
3127 smtp_transport_options_block *ob =
3128 (smtp_transport_options_block *)(tblock->options_block);
3129 smtp_inblock inblock;
3130 smtp_outblock outblock;
3132 uschar inbuffer[4096];
3133 uschar outbuffer[16];
3135 inblock.sock = fileno(stdin);
3136 inblock.buffer = inbuffer;
3137 inblock.buffersize = sizeof(inbuffer);
3138 inblock.ptr = inbuffer;
3139 inblock.ptrend = inbuffer;
3141 outblock.sock = inblock.sock;
3142 outblock.buffersize = sizeof(outbuffer);
3143 outblock.buffer = outbuffer;
3144 outblock.ptr = outbuffer;
3145 outblock.cmd_count = 0;
3146 outblock.authenticating = FALSE;
3148 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
3149 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
3150 ob->command_timeout);
3151 (void)close(inblock.sock);
3156 /*************************************************
3157 * Prepare addresses for delivery *
3158 *************************************************/
3160 /* This function is called to flush out error settings from previous delivery
3161 attempts to other hosts. It also records whether we got here via an MX record
3162 or not in the more_errno field of the address. We are interested only in
3163 addresses that are still marked DEFER - others may have got delivered to a
3164 previously considered IP address. Set their status to PENDING_DEFER to indicate
3165 which ones are relevant this time.
3168 addrlist the list of addresses
3169 host the host we are delivering to
3171 Returns: the first address for this delivery
3174 static address_item *
3175 prepare_addresses(address_item *addrlist, host_item *host)
3177 address_item *first_addr = NULL;
3179 for (addr = addrlist; addr != NULL; addr = addr->next)
3180 if (addr->transport_return == DEFER)
3182 if (first_addr == NULL) first_addr = addr;
3183 addr->transport_return = PENDING_DEFER;
3184 addr->basic_errno = 0;
3185 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
3186 addr->message = NULL;
3188 addr->cipher = NULL;
3189 addr->ourcert = NULL;
3190 addr->peercert = NULL;
3191 addr->peerdn = NULL;
3192 addr->ocsp = OCSP_NOT_REQ;
3194 #ifdef EXPERIMENTAL_DSN_INFO
3195 addr->smtp_greeting = NULL;
3196 addr->helo_response = NULL;
3204 /*************************************************
3205 * Main entry point *
3206 *************************************************/
3208 /* See local README for interface details. As this is a remote transport, it is
3209 given a chain of addresses to be delivered in one connection, if possible. It
3210 always returns TRUE, indicating that each address has its own independent
3211 status set, except if there is a setting up problem, in which case it returns
3215 smtp_transport_entry(
3216 transport_instance *tblock, /* data for this instantiation */
3217 address_item *addrlist) /* addresses we are working on */
3221 int hosts_defer = 0;
3223 int hosts_looked_up = 0;
3224 int hosts_retry = 0;
3225 int hosts_serial = 0;
3226 int hosts_total = 0;
3227 int total_hosts_tried = 0;
3229 BOOL expired = TRUE;
3230 BOOL continuing = continue_hostname != NULL;
3231 uschar *expanded_hosts = NULL;
3233 uschar *tid = string_sprintf("%s transport", tblock->name);
3234 smtp_transport_options_block *ob =
3235 (smtp_transport_options_block *)(tblock->options_block);
3236 host_item *hostlist = addrlist->host_list;
3237 host_item *host = NULL;
3241 debug_printf("%s transport entered\n", tblock->name);
3242 for (addr = addrlist; addr != NULL; addr = addr->next)
3243 debug_printf(" %s\n", addr->address);
3244 if (continuing) debug_printf("already connected to %s [%s]\n",
3245 continue_hostname, continue_host_address);
3248 /* Set the flag requesting that these hosts be added to the waiting
3249 database if the delivery fails temporarily or if we are running with
3250 queue_smtp or a 2-stage queue run. This gets unset for certain
3251 kinds of error, typically those that are specific to the message. */
3253 update_waiting = TRUE;
3255 /* If a host list is not defined for the addresses - they must all have the
3256 same one in order to be passed to a single transport - or if the transport has
3257 a host list with hosts_override set, use the host list supplied with the
3258 transport. It is an error for this not to exist. */
3260 if (hostlist == NULL || (ob->hosts_override && ob->hosts != NULL))
3262 if (ob->hosts == NULL)
3264 addrlist->message = string_sprintf("%s transport called with no hosts set",
3266 addrlist->transport_return = PANIC;
3267 return FALSE; /* Only top address has status */
3270 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
3273 /* If the transport's host list contains no '$' characters, and we are not
3274 randomizing, it is fixed and therefore a chain of hosts can be built once
3275 and for all, and remembered for subsequent use by other calls to this
3276 transport. If, on the other hand, the host list does contain '$', or we are
3277 randomizing its order, we have to rebuild it each time. In the fixed case,
3278 as the hosts string will never be used again, it doesn't matter that we
3279 replace all the : characters with zeros. */
3281 if (ob->hostlist == NULL)
3283 uschar *s = ob->hosts;
3285 if (Ustrchr(s, '$') != NULL)
3287 if (!(expanded_hosts = expand_string(s)))
3289 addrlist->message = string_sprintf("failed to expand list of hosts "
3290 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
3291 addrlist->transport_return = search_find_defer? DEFER : PANIC;
3292 return FALSE; /* Only top address has status */
3294 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
3295 "\"%s\"\n", s, expanded_hosts);
3299 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
3301 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
3303 /* Check that the expansion yielded something useful. */
3304 if (hostlist == NULL)
3307 string_sprintf("%s transport has empty hosts setting", tblock->name);
3308 addrlist->transport_return = PANIC;
3309 return FALSE; /* Only top address has status */
3312 /* If there was no expansion of hosts, save the host list for
3315 if (!expanded_hosts) ob->hostlist = hostlist;
3318 /* This is not the first time this transport has been run in this delivery;
3319 the host list was built previously. */
3322 hostlist = ob->hostlist;
3325 /* The host list was supplied with the address. If hosts_randomize is set, we
3326 must sort it into a random order if it did not come from MX records and has not
3327 already been randomized (but don't bother if continuing down an existing
3330 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continuing)
3332 host_item *newlist = NULL;
3333 while (hostlist != NULL)
3335 host_item *h = hostlist;
3336 hostlist = hostlist->next;
3338 h->sort_key = random_number(100);
3340 if (newlist == NULL)
3345 else if (h->sort_key < newlist->sort_key)
3352 host_item *hh = newlist;
3353 while (hh->next != NULL)
3355 if (h->sort_key < hh->next->sort_key) break;
3363 hostlist = addrlist->host_list = newlist;
3366 /* Sort out the default port. */
3368 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
3370 /* For each host-plus-IP-address on the list:
3372 . If this is a continued delivery and the host isn't the one with the
3373 current connection, skip.
3375 . If the status is unusable (i.e. previously failed or retry checked), skip.
3377 . If no IP address set, get the address, either by turning the name into
3378 an address, calling gethostbyname if gethostbyname is on, or by calling
3379 the DNS. The DNS may yield multiple addresses, in which case insert the
3380 extra ones into the list.
3382 . Get the retry data if not previously obtained for this address and set the
3383 field which remembers the state of this address. Skip if the retry time is
3384 not reached. If not, remember whether retry data was found. The retry string
3385 contains both the name and the IP address.
3387 . Scan the list of addresses and mark those whose status is DEFER as
3388 PENDING_DEFER. These are the only ones that will be processed in this cycle
3391 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
3392 Some addresses may be successfully delivered, others may fail, and yet
3393 others may get temporary errors and so get marked DEFER.
3395 . The return from the delivery attempt is OK if a connection was made and a
3396 valid SMTP dialogue was completed. Otherwise it is DEFER.
3398 . If OK, add a "remove" retry item for this host/IPaddress, if any.
3400 . If fail to connect, or other defer state, add a retry item.
3402 . If there are any addresses whose status is still DEFER, carry on to the
3403 next host/IPaddress, unless we have tried the number of hosts given
3404 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
3405 there is some fancy logic for hosts_max_try that means its limit can be
3406 overstepped in some circumstances.
3408 If we get to the end of the list, all hosts have deferred at least one address,
3409 or not reached their retry times. If delay_after_cutoff is unset, it requests a
3410 delivery attempt to those hosts whose last try was before the arrival time of
3411 the current message. To cope with this, we have to go round the loop a second
3412 time. After that, set the status and error data for any addresses that haven't
3413 had it set already. */
3415 for (cutoff_retry = 0; expired &&
3416 cutoff_retry < ((ob->delay_after_cutoff)? 1 : 2);
3419 host_item *nexthost = NULL;
3420 int unexpired_hosts_tried = 0;
3422 for (host = hostlist;
3424 unexpired_hosts_tried < ob->hosts_max_try &&
3425 total_hosts_tried < ob->hosts_max_try_hardlimit;
3431 BOOL serialized = FALSE;
3432 BOOL host_is_expired = FALSE;
3433 BOOL message_defer = FALSE;
3434 BOOL some_deferred = FALSE;
3435 address_item *first_addr = NULL;
3436 uschar *interface = NULL;
3437 uschar *retry_host_key = NULL;
3438 uschar *retry_message_key = NULL;
3439 uschar *serialize_key = NULL;
3441 /* Default next host is next host. :-) But this can vary if the
3442 hosts_max_try limit is hit (see below). It may also be reset if a host
3443 address is looked up here (in case the host was multihomed). */
3445 nexthost = host->next;
3447 /* If the address hasn't yet been obtained from the host name, look it up
3448 now, unless the host is already marked as unusable. If it is marked as
3449 unusable, it means that the router was unable to find its IP address (in
3450 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
3451 the lookup failed last time. We don't get this far if *all* MX records
3452 point to non-existent hosts; that is treated as a hard error.
3454 We can just skip this host entirely. When the hosts came from the router,
3455 the address will timeout based on the other host(s); when the address is
3456 looked up below, there is an explicit retry record added.
3458 Note that we mustn't skip unusable hosts if the address is not unset; they
3459 may be needed as expired hosts on the 2nd time round the cutoff loop. */
3461 if (host->address == NULL)
3463 int new_port, flags;
3466 if (host->status >= hstatus_unusable)
3468 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
3473 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
3475 /* The host name is permitted to have an attached port. Find it, and
3476 strip it from the name. Just remember it for now. */
3478 new_port = host_item_get_port(host);
3480 /* Count hosts looked up */
3484 /* Find by name if so configured, or if it's an IP address. We don't
3485 just copy the IP address, because we need the test-for-local to happen. */
3487 flags = HOST_FIND_BY_A;
3488 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
3489 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
3491 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
3492 rc = host_find_byname(host, NULL, flags, NULL, TRUE);
3494 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
3495 &ob->dnssec, /* domains for request/require */
3498 /* Update the host (and any additional blocks, resulting from
3499 multihoming) with a host-specific port, if any. */
3501 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
3503 /* Failure to find the host at this time (usually DNS temporary failure)
3504 is really a kind of routing failure rather than a transport failure.
3505 Therefore we add a retry item of the routing kind, not to stop us trying
3506 to look this name up here again, but to ensure the address gets timed
3507 out if the failures go on long enough. A complete failure at this point
3508 commonly points to a configuration error, but the best action is still
3509 to carry on for the next host. */
3511 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
3513 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
3515 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
3516 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
3517 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
3518 host->status = hstatus_unusable;
3520 for (addr = addrlist; addr != NULL; addr = addr->next)
3522 if (addr->transport_return != DEFER) continue;
3523 addr->basic_errno = ERRNO_UNKNOWNHOST;
3525 string_sprintf("failed to lookup IP address for %s", host->name);
3530 /* If the host is actually the local host, we may have a problem, or
3531 there may be some cunning configuration going on. In the problem case,
3532 log things and give up. The default transport status is already DEFER. */
3534 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
3536 for (addr = addrlist; addr != NULL; addr = addr->next)
3538 addr->basic_errno = 0;
3539 addr->message = string_sprintf("%s transport found host %s to be "
3540 "local", tblock->name, host->name);
3544 } /* End of block for IP address lookup */
3546 /* If this is a continued delivery, we are interested only in the host
3547 which matches the name of the existing open channel. The check is put
3548 here after the local host lookup, in case the name gets expanded as a
3549 result of the lookup. Set expired FALSE, to save the outer loop executing
3552 if (continuing && (Ustrcmp(continue_hostname, host->name) != 0 ||
3553 Ustrcmp(continue_host_address, host->address) != 0))
3556 continue; /* With next host */
3559 /* Reset the default next host in case a multihomed host whose addresses
3560 are not looked up till just above added to the host list. */
3562 nexthost = host->next;
3564 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
3565 domain is in queue_smtp_domains, we don't actually want to attempt any
3566 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
3567 there is a lookup defer in queue_smtp_domains, proceed as if the domain
3568 were not in it. We don't want to hold up all SMTP deliveries! Except when
3569 doing a two-stage queue run, don't do this if forcing. */
3571 if ((!deliver_force || queue_2stage) && (queue_smtp ||
3572 match_isinlist(addrlist->domain,
3573 (const uschar **)&queue_smtp_domains, 0,
3574 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
3577 for (addr = addrlist; addr != NULL; addr = addr->next)
3579 if (addr->transport_return != DEFER) continue;
3580 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
3582 continue; /* With next host */
3585 /* Count hosts being considered - purely for an intelligent comment
3586 if none are usable. */
3590 /* Set $host and $host address now in case they are needed for the
3591 interface expansion or the serialize_hosts check; they remain set if an
3592 actual delivery happens. */
3594 deliver_host = host->name;
3595 deliver_host_address = host->address;
3596 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
3597 : host->dnssec == DS_NO ? US"no"
3600 /* Set up a string for adding to the retry key if the port number is not
3601 the standard SMTP port. A host may have its own port setting that overrides
3604 pistring = string_sprintf(":%d", (host->port == PORT_NONE)?
3606 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
3608 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
3609 string is set, even if constant (as different transports can have different
3610 constant settings), we must add it to the key that is used for retries,
3611 because connections to the same host from a different interface should be
3612 treated separately. */
3614 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET : AF_INET6;
3615 if ((rs = ob->interface) && *rs)
3617 if (!smtp_get_interface(rs, host_af, addrlist, &interface, tid))
3619 pistring = string_sprintf("%s/%s", pistring, interface);
3622 /* The first time round the outer loop, check the status of the host by
3623 inspecting the retry data. The second time round, we are interested only
3624 in expired hosts that haven't been tried since this message arrived. */
3626 if (cutoff_retry == 0)
3629 /* Ensure the status of the address is set by checking retry data if
3630 necessary. There may be host-specific retry data (applicable to all
3631 messages) and also data for retries of a specific message at this host.
3632 If either of these retry records are actually read, the keys used are
3633 returned to save recomputing them later. */
3635 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3636 US"retry_include_ip_address", ob->retry_include_ip_address,
3637 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3638 continue; /* with next host */
3640 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
3641 incl_ip, &retry_host_key, &retry_message_key);
3643 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
3644 (host->address == NULL)? US"" : host->address, pistring,
3645 (host->status == hstatus_usable)? "usable" :
3646 (host->status == hstatus_unusable)? "unusable" :
3647 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
3649 /* Skip this address if not usable at this time, noting if it wasn't
3650 actually expired, both locally and in the address. */
3652 switch (host->status)
3654 case hstatus_unusable:
3656 setflag(addrlist, af_retry_skipped);
3659 case hstatus_unusable_expired:
3662 case hwhy_retry: hosts_retry++; break;
3663 case hwhy_failed: hosts_fail++; break;
3664 case hwhy_deferred: hosts_defer++; break;
3667 /* If there was a retry message key, implying that previously there
3668 was a message-specific defer, we don't want to update the list of
3669 messages waiting for these hosts. */
3671 if (retry_message_key != NULL) update_waiting = FALSE;
3672 continue; /* With the next host or IP address */
3676 /* Second time round the loop: if the address is set but expired, and
3677 the message is newer than the last try, let it through. */
3681 if (host->address == NULL ||
3682 host->status != hstatus_unusable_expired ||
3683 host->last_try > received_time)
3686 debug_printf("trying expired host %s [%s]%s\n",
3687 host->name, host->address, pistring);
3688 host_is_expired = TRUE;
3691 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
3692 it remains TRUE only if all hosts are expired and none are actually tried.
3697 /* If this host is listed as one to which access must be serialized,
3698 see if another Exim process has a connection to it, and if so, skip
3699 this host. If not, update the database to record our connection to it
3700 and remember this for later deletion. Do not do any of this if we are
3701 sending the message down a pre-existing connection. */
3704 verify_check_given_host(&ob->serialize_hosts, host) == OK)
3706 serialize_key = string_sprintf("host-serialize-%s", host->name);
3707 if (!enq_start(serialize_key, 1))
3710 debug_printf("skipping host %s because another Exim process "
3711 "is connected to it\n", host->name);
3718 /* OK, we have an IP address that is not waiting for its retry time to
3719 arrive (it might be expired) OR (second time round the loop) we have an
3720 expired host that hasn't been tried since the message arrived. Have a go
3721 at delivering the message to it. First prepare the addresses by flushing
3722 out the result of previous attempts, and finding the first address that
3723 is still to be delivered. */
3725 first_addr = prepare_addresses(addrlist, host);
3727 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
3728 message_id, host->name, host->address, addrlist->address,
3729 (addrlist->next == NULL)? "" : ", ...");
3731 set_process_info("delivering %s to %s [%s] (%s%s)",
3732 message_id, host->name, host->address, addrlist->address,
3733 (addrlist->next == NULL)? "" : ", ...");
3735 /* This is not for real; don't do the delivery. If there are
3736 any remaining hosts, list them. */
3741 set_errno_nohost(addrlist, 0, NULL, OK, FALSE);
3742 for (addr = addrlist; addr != NULL; addr = addr->next)
3744 addr->host_used = host;
3745 addr->special_action = '*';
3746 addr->message = US"delivery bypassed by -N option";
3750 debug_printf("*** delivery by %s transport bypassed by -N option\n"
3751 "*** host and remaining hosts:\n", tblock->name);
3752 for (host2 = host; host2 != NULL; host2 = host2->next)
3753 debug_printf(" %s [%s]\n", host2->name,
3754 (host2->address == NULL)? US"unset" : host2->address);
3759 /* This is for real. If the host is expired, we don't count it for
3760 hosts_max_retry. This ensures that all hosts must expire before an address
3761 is timed out, unless hosts_max_try_hardlimit (which protects against
3762 lunatic DNS configurations) is reached.
3764 If the host is not expired and we are about to hit the hosts_max_retry
3765 limit, check to see if there is a subsequent hosts with a different MX
3766 value. If so, make that the next host, and don't count this one. This is a
3767 heuristic to make sure that different MXs do get tried. With a normal kind
3768 of retry rule, they would get tried anyway when the earlier hosts were
3769 delayed, but if the domain has a "retry every time" type of rule - as is
3770 often used for the the very large ISPs, that won't happen. */
3775 /* Make a copy of the host if it is local to this invocation
3776 of the transport. */
3780 thost = store_get(sizeof(host_item));
3782 thost->name = string_copy(host->name);
3783 thost->address = string_copy(host->address);
3788 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
3792 debug_printf("hosts_max_try limit reached with this host\n");
3793 for (h = host; h; h = h->next) if (h->mx != host->mx)
3796 unexpired_hosts_tried--;
3797 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
3798 "and will be tried\n");
3803 /* Attempt the delivery. */
3805 total_hosts_tried++;
3806 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
3807 &message_defer, FALSE);
3810 OK => connection made, each address contains its result;
3811 message_defer is set for message-specific defers (when all
3812 recipients are marked defer)
3813 DEFER => there was a non-message-specific delivery problem;
3814 ERROR => there was a problem setting up the arguments for a filter,
3815 or there was a problem with expanding added headers
3818 /* If the result is not OK, there was a non-message-specific problem.
3819 If the result is DEFER, we need to write to the logs saying what happened
3820 for this particular host, except in the case of authentication and TLS
3821 failures, where the log has already been written. If all hosts defer a
3822 general message is written at the end. */
3824 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL &&
3825 first_addr->basic_errno != ERRNO_TLSFAILURE)
3826 write_logs(first_addr, host);
3828 #ifndef DISABLE_EVENT
3830 deferred_event_raise(first_addr, host);
3833 /* If STARTTLS was accepted, but there was a failure in setting up the
3834 TLS session (usually a certificate screwup), and the host is not in
3835 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
3836 TLS forcibly turned off. We have to start from scratch with a new SMTP
3837 connection. That's why the retry is done from here, not from within
3838 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
3839 session, so the in-clear transmission after those errors, if permitted,
3840 happens inside smtp_deliver().] */
3844 && first_addr->basic_errno == ERRNO_TLSFAILURE
3845 && ob->tls_tempfail_tryclear
3846 && verify_check_given_host(&ob->hosts_require_tls, host) != OK
3849 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
3850 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
3851 first_addr = prepare_addresses(addrlist, host);
3852 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
3853 &message_defer, TRUE);
3854 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
3855 write_logs(first_addr, host);
3856 # ifndef DISABLE_EVENT
3858 deferred_event_raise(first_addr, host);
3861 #endif /*SUPPORT_TLS*/
3864 /* Delivery attempt finished */
3866 rs = (rc == OK)? US"OK" : (rc == DEFER)? US"DEFER" : (rc == ERROR)?
3869 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
3870 message_id, host->name, host->address, addrlist->address,
3871 (addrlist->next == NULL)? "" : " (& others)", rs);
3873 /* Release serialization if set up */
3875 if (serialized) enq_end(serialize_key);
3877 /* If the result is DEFER, or if a host retry record is known to exist, we
3878 need to add an item to the retry chain for updating the retry database
3879 at the end of delivery. We only need to add the item to the top address,
3880 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
3881 for any other delivery attempts using the same address. (It is copied into
3882 the unusable tree at the outer level, so even if different address blocks
3883 contain the same address, it still won't get tried again.) */
3885 if (rc == DEFER || retry_host_key != NULL)
3887 int delete_flag = (rc != DEFER)? rf_delete : 0;
3888 if (retry_host_key == NULL)
3891 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3892 US"retry_include_ip_address", ob->retry_include_ip_address,
3893 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3894 incl_ip = TRUE; /* error; use most-specific retry record */
3896 retry_host_key = incl_ip ?
3897 string_sprintf("T:%S:%s%s", host->name, host->address, pistring) :
3898 string_sprintf("T:%S%s", host->name, pistring);
3901 /* If a delivery of another message over an existing SMTP connection
3902 yields DEFER, we do NOT set up retry data for the host. This covers the
3903 case when there are delays in routing the addresses in the second message
3904 that are so long that the server times out. This is alleviated by not
3905 routing addresses that previously had routing defers when handling an
3906 existing connection, but even so, this case may occur (e.g. if a
3907 previously happily routed address starts giving routing defers). If the
3908 host is genuinely down, another non-continued message delivery will
3909 notice it soon enough. */
3911 if (delete_flag != 0 || !continuing)
3912 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
3914 /* We may have tried an expired host, if its retry time has come; ensure
3915 the status reflects the expiry for the benefit of any other addresses. */
3919 host->status = (host_is_expired)?
3920 hstatus_unusable_expired : hstatus_unusable;
3921 host->why = hwhy_deferred;
3925 /* If message_defer is set (host was OK, but every recipient got deferred
3926 because of some message-specific problem), or if that had happened
3927 previously so that a message retry key exists, add an appropriate item
3928 to the retry chain. Note that if there was a message defer but now there is
3929 a host defer, the message defer record gets deleted. That seems perfectly
3930 reasonable. Also, stop the message from being remembered as waiting
3931 for specific hosts. */
3933 if (message_defer || retry_message_key != NULL)
3935 int delete_flag = message_defer? 0 : rf_delete;
3936 if (retry_message_key == NULL)
3939 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3940 US"retry_include_ip_address", ob->retry_include_ip_address,
3941 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3942 incl_ip = TRUE; /* error; use most-specific retry record */
3944 retry_message_key = incl_ip ?
3945 string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
3947 string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
3949 retry_add_item(addrlist, retry_message_key,
3950 rf_message | rf_host | delete_flag);
3951 update_waiting = FALSE;
3954 /* Any return other than DEFER (that is, OK or ERROR) means that the
3955 addresses have got their final statuses filled in for this host. In the OK
3956 case, see if any of them are deferred. */
3959 for (addr = addrlist; addr; addr = addr->next)
3960 if (addr->transport_return == DEFER)
3962 some_deferred = TRUE;
3966 /* If no addresses deferred or the result was ERROR, return. We do this for
3967 ERROR because a failing filter set-up or add_headers expansion is likely to
3968 fail for any host we try. */
3970 if (rc == ERROR || (rc == OK && !some_deferred))
3972 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3973 return TRUE; /* Each address has its status */
3976 /* If the result was DEFER or some individual addresses deferred, let
3977 the loop run to try other hosts with the deferred addresses, except for the
3978 case when we were trying to deliver down an existing channel and failed.
3979 Don't try any other hosts in this case. */
3981 if (continuing) break;
3983 /* If the whole delivery, or some individual addresses, were deferred and
3984 there are more hosts that could be tried, do not count this host towards
3985 the hosts_max_try limit if the age of the message is greater than the
3986 maximum retry time for this host. This means we may try try all hosts,
3987 ignoring the limit, when messages have been around for some time. This is
3988 important because if we don't try all hosts, the address will never time
3989 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
3991 if ((rc == DEFER || some_deferred) && nexthost != NULL)
3994 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
3996 if (retry != NULL && retry->rules != NULL)
3998 retry_rule *last_rule;
3999 for (last_rule = retry->rules;
4000 last_rule->next != NULL;
4001 last_rule = last_rule->next);
4002 timedout = time(NULL) - received_time > last_rule->timeout;
4004 else timedout = TRUE; /* No rule => timed out */
4008 unexpired_hosts_tried--;
4009 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
4010 "hosts_max_try (message older than host's retry time)\n");
4013 } /* End of loop for trying multiple hosts. */
4015 /* This is the end of the loop that repeats iff expired is TRUE and
4016 ob->delay_after_cutoff is FALSE. The second time round we will
4017 try those hosts that haven't been tried since the message arrived. */
4021 debug_printf("all IP addresses skipped or deferred at least one address\n");
4022 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
4023 debug_printf("retrying IP addresses not tried since message arrived\n");
4028 /* Get here if all IP addresses are skipped or defer at least one address. In
4029 MUA wrapper mode, this will happen only for connection or other non-message-
4030 specific failures. Force the delivery status for all addresses to FAIL. */
4034 for (addr = addrlist; addr != NULL; addr = addr->next)
4035 addr->transport_return = FAIL;
4039 /* In the normal, non-wrapper case, add a standard message to each deferred
4040 address if there hasn't been an error, that is, if it hasn't actually been
4041 tried this time. The variable "expired" will be FALSE if any deliveries were
4042 actually tried, or if there was at least one host that was not expired. That
4043 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
4044 a delivery has been tried, an error code will be set, and the failing of the
4045 message is handled by the retry code later.
4047 If queue_smtp is set, or this transport was called to send a subsequent message
4048 down an existing TCP/IP connection, and something caused the host not to be
4049 found, we end up here, but can detect these cases and handle them specially. */
4051 for (addr = addrlist; addr; addr = addr->next)
4053 /* If host is not NULL, it means that we stopped processing the host list
4054 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
4055 means we need to behave as if some hosts were skipped because their retry
4056 time had not come. Specifically, this prevents the address from timing out.
4057 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
4058 hosts were tried. */
4061 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
4064 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
4065 "hosts were tried\n");
4070 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
4071 setflag(addr, af_retry_skipped);
4074 if (queue_smtp) /* no deliveries attempted */
4076 addr->transport_return = DEFER;
4077 addr->basic_errno = 0;
4078 addr->message = US"SMTP delivery explicitly queued";
4081 else if ( addr->transport_return == DEFER
4082 && (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0)
4086 addr->basic_errno = ERRNO_HRETRY;
4087 if (continue_hostname)
4088 addr->message = US"no host found for existing SMTP connection";
4091 setflag(addr, af_pass_message); /* This is not a security risk */
4092 addr->message = string_sprintf(
4093 "all hosts%s have been failing for a long time %s",
4094 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"",
4095 ob->delay_after_cutoff
4096 ? US"(and retry time not reached)"
4097 : US"and were last tried after this message arrived");
4099 /* If we are already using fallback hosts, or there are no fallback hosts
4100 defined, convert the result to FAIL to cause a bounce. */
4102 if (addr->host_list == addr->fallback_hosts || !addr->fallback_hosts)
4103 addr->transport_return = FAIL;
4108 if (hosts_retry == hosts_total)
4109 s = "retry time not reached for any host%s";
4110 else if (hosts_fail == hosts_total)
4111 s = "all host address lookups%s failed permanently";
4112 else if (hosts_defer == hosts_total)
4113 s = "all host address lookups%s failed temporarily";
4114 else if (hosts_serial == hosts_total)
4115 s = "connection limit reached for all hosts%s";
4116 else if (hosts_fail+hosts_defer == hosts_total)
4117 s = "all host address lookups%s failed";
4119 s = "some host address lookups failed and retry time "
4120 "not reached for other hosts or connection limit reached%s";
4122 addr->message = string_sprintf(s,
4123 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"");
4128 /* Update the database which keeps information about which messages are waiting
4129 for which hosts to become available. For some message-specific errors, the
4130 update_waiting flag is turned off because we don't want follow-on deliveries in
4131 those cases. If this transport instance is explicitly limited to one message
4132 per connection then follow-on deliveries are not possible and there's no need
4133 to create/update the per-transport wait-<transport_name> database. */
4135 if (update_waiting && tblock->connection_max_messages != 1)
4136 transport_update_waiting(hostlist, tblock->name);
4140 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
4142 return TRUE; /* Each address has its status */
4147 /* End of transport/smtp.c */