1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2017 */
6 /* See the file NOTICE for conditions of use and distribution. */
12 /* Options specific to the smtp transport. This transport also supports LMTP
13 over TCP/IP. The options must be in alphabetic order (note that "_" comes
14 before the lower case letters). Some live in the transport_instance block so as
15 to be publicly visible; these are flagged with opt_public. */
17 optionlist smtp_transport_options[] = {
18 { "*expand_multi_domain", opt_stringptr | opt_hidden | opt_public,
19 (void *)offsetof(transport_instance, expand_multi_domain) },
20 { "*expand_retry_include_ip_address", opt_stringptr | opt_hidden,
21 (void *)(offsetof(smtp_transport_options_block, expand_retry_include_ip_address)) },
23 { "address_retry_include_sender", opt_bool,
24 (void *)offsetof(smtp_transport_options_block, address_retry_include_sender) },
25 { "allow_localhost", opt_bool,
26 (void *)offsetof(smtp_transport_options_block, allow_localhost) },
27 { "authenticated_sender", opt_stringptr,
28 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
29 { "authenticated_sender_force", opt_bool,
30 (void *)offsetof(smtp_transport_options_block, authenticated_sender_force) },
31 { "command_timeout", opt_time,
32 (void *)offsetof(smtp_transport_options_block, command_timeout) },
33 { "connect_timeout", opt_time,
34 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
35 { "connection_max_messages", opt_int | opt_public,
36 (void *)offsetof(transport_instance, connection_max_messages) },
37 { "data_timeout", opt_time,
38 (void *)offsetof(smtp_transport_options_block, data_timeout) },
39 { "delay_after_cutoff", opt_bool,
40 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
42 { "dkim_canon", opt_stringptr,
43 (void *)offsetof(smtp_transport_options_block, dkim.dkim_canon) },
44 { "dkim_domain", opt_stringptr,
45 (void *)offsetof(smtp_transport_options_block, dkim.dkim_domain) },
46 { "dkim_private_key", opt_stringptr,
47 (void *)offsetof(smtp_transport_options_block, dkim.dkim_private_key) },
48 { "dkim_selector", opt_stringptr,
49 (void *)offsetof(smtp_transport_options_block, dkim.dkim_selector) },
50 { "dkim_sign_headers", opt_stringptr,
51 (void *)offsetof(smtp_transport_options_block, dkim.dkim_sign_headers) },
52 { "dkim_strict", opt_stringptr,
53 (void *)offsetof(smtp_transport_options_block, dkim.dkim_strict) },
55 { "dns_qualify_single", opt_bool,
56 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
57 { "dns_search_parents", opt_bool,
58 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
59 { "dnssec_request_domains", opt_stringptr,
60 (void *)offsetof(smtp_transport_options_block, dnssec.request) },
61 { "dnssec_require_domains", opt_stringptr,
62 (void *)offsetof(smtp_transport_options_block, dnssec.require) },
63 { "dscp", opt_stringptr,
64 (void *)offsetof(smtp_transport_options_block, dscp) },
65 { "fallback_hosts", opt_stringptr,
66 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
67 { "final_timeout", opt_time,
68 (void *)offsetof(smtp_transport_options_block, final_timeout) },
69 { "gethostbyname", opt_bool,
70 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
71 { "helo_data", opt_stringptr,
72 (void *)offsetof(smtp_transport_options_block, helo_data) },
73 { "hosts", opt_stringptr,
74 (void *)offsetof(smtp_transport_options_block, hosts) },
75 { "hosts_avoid_esmtp", opt_stringptr,
76 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
77 { "hosts_avoid_pipelining", opt_stringptr,
78 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
80 { "hosts_avoid_tls", opt_stringptr,
81 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
83 { "hosts_max_try", opt_int,
84 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
85 { "hosts_max_try_hardlimit", opt_int,
86 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
88 { "hosts_nopass_tls", opt_stringptr,
89 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
90 { "hosts_noproxy_tls", opt_stringptr,
91 (void *)offsetof(smtp_transport_options_block, hosts_noproxy_tls) },
93 { "hosts_override", opt_bool,
94 (void *)offsetof(smtp_transport_options_block, hosts_override) },
95 { "hosts_randomize", opt_bool,
96 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
97 #if defined(SUPPORT_TLS) && !defined(DISABLE_OCSP)
98 { "hosts_request_ocsp", opt_stringptr,
99 (void *)offsetof(smtp_transport_options_block, hosts_request_ocsp) },
101 { "hosts_require_auth", opt_stringptr,
102 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
104 # ifdef EXPERIMENTAL_DANE
105 { "hosts_require_dane", opt_stringptr,
106 (void *)offsetof(smtp_transport_options_block, hosts_require_dane) },
108 # ifndef DISABLE_OCSP
109 { "hosts_require_ocsp", opt_stringptr,
110 (void *)offsetof(smtp_transport_options_block, hosts_require_ocsp) },
112 { "hosts_require_tls", opt_stringptr,
113 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
115 { "hosts_try_auth", opt_stringptr,
116 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
117 { "hosts_try_chunking", opt_stringptr,
118 (void *)offsetof(smtp_transport_options_block, hosts_try_chunking) },
119 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
120 { "hosts_try_dane", opt_stringptr,
121 (void *)offsetof(smtp_transport_options_block, hosts_try_dane) },
123 { "hosts_try_fastopen", opt_stringptr,
124 (void *)offsetof(smtp_transport_options_block, hosts_try_fastopen) },
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 */
210 NULL, /* hosts_try_fastopen */
212 US"*", /* hosts_try_prdr */
215 US"*", /* hosts_request_ocsp (except under DANE; tls_client_start()) */
216 NULL, /* hosts_require_ocsp */
218 NULL, /* hosts_require_tls */
219 NULL, /* hosts_avoid_tls */
220 NULL, /* hosts_verify_avoid_tls */
221 NULL, /* hosts_avoid_pipelining */
222 NULL, /* hosts_avoid_esmtp */
224 NULL, /* hosts_nopass_tls */
225 US"*", /* hosts_noproxy_tls */
227 5*60, /* command_timeout */
228 5*60, /* connect_timeout; shorter system default overrides */
229 5*60, /* data timeout */
230 10*60, /* final timeout */
231 1024, /* size_addition */
232 5, /* hosts_max_try */
233 50, /* hosts_max_try_hardlimit */
234 TRUE, /* address_retry_include_sender */
235 FALSE, /* allow_localhost */
236 FALSE, /* authenticated_sender_force */
237 FALSE, /* gethostbyname */
238 TRUE, /* dns_qualify_single */
239 FALSE, /* dns_search_parents */
240 { NULL, NULL }, /* dnssec_domains {request,require} */
241 TRUE, /* delay_after_cutoff */
242 FALSE, /* hosts_override */
243 FALSE, /* hosts_randomize */
244 TRUE, /* keepalive */
245 FALSE, /* lmtp_ignore_quota */
246 NULL, /* expand_retry_include_ip_address */
247 TRUE /* retry_include_ip_address */
249 ,NULL /* socks_proxy */
252 ,NULL, /* tls_certificate */
254 NULL, /* tls_privatekey */
255 NULL, /* tls_require_ciphers */
257 US"system", /* tls_verify_certificates */
258 EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
259 /* tls_dh_min_bits */
260 TRUE, /* tls_tempfail_tryclear */
261 NULL, /* tls_verify_hosts */
262 US"*", /* tls_try_verify_hosts */
263 US"*" /* tls_verify_cert_hostnames */
266 , {NULL, /* dkim_canon */
267 NULL, /* dkim_domain */
268 NULL, /* dkim_private_key */
269 NULL, /* dkim_selector */
270 NULL, /* dkim_sign_headers */
271 NULL, /* dkim_strict */
272 FALSE} /* dot_stuffed */
276 /* some DSN flags for use later */
278 static int rf_list[] = {rf_notify_never, rf_notify_success,
279 rf_notify_failure, rf_notify_delay };
281 static uschar *rf_names[] = { US"NEVER", US"SUCCESS", US"FAILURE", US"DELAY" };
287 static uschar *smtp_command; /* Points to last cmd for error messages */
288 static uschar *mail_command; /* Points to MAIL cmd for error messages */
289 static uschar *data_command = US""; /* Points to DATA cmd for error messages */
290 static BOOL update_waiting; /* TRUE to update the "wait" database */
292 /*XXX move to smtp_context */
293 static BOOL pipelining_active; /* current transaction is in pipe mode */
296 /*************************************************
297 * Setup entry point *
298 *************************************************/
300 /* This function is called when the transport is about to be used,
301 but before running it in a sub-process. It is used for two things:
303 (1) To set the fallback host list in addresses, when delivering.
304 (2) To pass back the interface, port, protocol, and other options, for use
305 during callout verification.
308 tblock pointer to the transport instance block
309 addrlist list of addresses about to be transported
310 tf if not NULL, pointer to block in which to return options
311 uid the uid that will be set (not used)
312 gid the gid that will be set (not used)
313 errmsg place for error message (not used)
315 Returns: OK always (FAIL, DEFER not used)
319 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
320 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
322 smtp_transport_options_block *ob =
323 (smtp_transport_options_block *)(tblock->options_block);
325 errmsg = errmsg; /* Keep picky compilers happy */
329 /* Pass back options if required. This interface is getting very messy. */
333 tf->interface = ob->interface;
335 tf->protocol = ob->protocol;
336 tf->hosts = ob->hosts;
337 tf->hosts_override = ob->hosts_override;
338 tf->hosts_randomize = ob->hosts_randomize;
339 tf->gethostbyname = ob->gethostbyname;
340 tf->qualify_single = ob->dns_qualify_single;
341 tf->search_parents = ob->dns_search_parents;
342 tf->helo_data = ob->helo_data;
345 /* Set the fallback host list for all the addresses that don't have fallback
346 host lists, provided that the local host wasn't present in the original host
349 if (!testflag(addrlist, af_local_host_removed))
350 for (; addrlist; addrlist = addrlist->next)
351 if (!addrlist->fallback_hosts) addrlist->fallback_hosts = ob->fallback_hostlist;
358 /*************************************************
359 * Initialization entry point *
360 *************************************************/
362 /* Called for each instance, after its options have been read, to
363 enable consistency checks to be done, or anything else that needs
366 Argument: pointer to the transport instance block
371 smtp_transport_init(transport_instance *tblock)
373 smtp_transport_options_block *ob =
374 (smtp_transport_options_block *)(tblock->options_block);
376 /* Retry_use_local_part defaults FALSE if unset */
378 if (tblock->retry_use_local_part == TRUE_UNSET)
379 tblock->retry_use_local_part = FALSE;
381 /* Set the default port according to the protocol */
383 if (ob->port == NULL)
384 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
385 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
387 /* Set up the setup entry point, to be called before subprocesses for this
390 tblock->setup = smtp_transport_setup;
392 /* Complain if any of the timeouts are zero. */
394 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
395 ob->final_timeout <= 0)
396 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
397 "command, data, or final timeout value is zero for %s transport",
400 /* If hosts_override is set and there are local hosts, set the global
401 flag that stops verify from showing router hosts. */
403 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
405 /* If there are any fallback hosts listed, build a chain of host items
406 for them, but do not do any lookups at this time. */
408 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
415 /*************************************************
416 * Set delivery info into all active addresses *
417 *************************************************/
419 /* Only addresses whose status is >= PENDING are relevant. A lesser
420 status means that an address is not currently being processed.
423 addrlist points to a chain of addresses
424 errno_value to put in each address's errno field
425 msg to put in each address's message field
426 rc to put in each address's transport_return field
427 pass_message if TRUE, set the "pass message" flag in the address
428 host if set, mark addrs as having used this host
429 smtp_greeting from peer
430 helo_response from peer
432 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
433 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
434 this particular type of timeout.
440 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
441 BOOL pass_message, host_item * host
442 #ifdef EXPERIMENTAL_DSN_INFO
443 , const uschar * smtp_greeting, const uschar * helo_response
449 if (errno_value == ERRNO_CONNECTTIMEOUT)
451 errno_value = ETIMEDOUT;
452 orvalue = RTEF_CTOUT;
454 for (addr = addrlist; addr; addr = addr->next)
455 if (addr->transport_return >= PENDING)
457 addr->basic_errno = errno_value;
458 addr->more_errno |= orvalue;
462 if (pass_message) setflag(addr, af_pass_message);
464 addr->transport_return = rc;
467 addr->host_used = host;
468 #ifdef EXPERIMENTAL_DSN_INFO
470 {uschar * s = Ustrchr(smtp_greeting, '\n'); if (s) *s = '\0';}
471 addr->smtp_greeting = smtp_greeting;
474 {uschar * s = Ustrchr(helo_response, '\n'); if (s) *s = '\0';}
475 addr->helo_response = helo_response;
482 set_errno_nohost(address_item *addrlist, int errno_value, uschar *msg, int rc,
485 set_errno(addrlist, errno_value, msg, rc, pass_message, NULL
486 #ifdef EXPERIMENTAL_DSN_INFO
493 /*************************************************
494 * Check an SMTP response *
495 *************************************************/
497 /* This function is given an errno code and the SMTP response buffer
498 to analyse, together with the host identification for generating messages. It
499 sets an appropriate message and puts the first digit of the response code into
500 the yield variable. If no response was actually read, a suitable digit is
504 host the current host, to get its name for messages
505 errno_value pointer to the errno value
506 more_errno from the top address for use with ERRNO_FILTER_FAIL
507 buffer the SMTP response buffer
508 yield where to put a one-digit SMTP response code
509 message where to put an error message
510 pass_message set TRUE if message is an SMTP response
512 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
516 check_response(host_item *host, int *errno_value, int more_errno,
517 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
519 uschar * pl = pipelining_active ? US"pipelined " : US"";
522 *yield = '4'; /* Default setting is to give a temporary error */
526 case ETIMEDOUT: /* Handle response timeout */
527 *message = US string_sprintf("SMTP timeout after %s%s",
529 if (transport_count > 0)
530 *message = US string_sprintf("%s (%d bytes written)", *message,
534 case ERRNO_SMTPFORMAT: /* Handle malformed SMTP response */
535 s = string_printing(buffer);
536 while (isspace(*s)) s++;
538 ? string_sprintf("Malformed SMTP reply (an empty line) "
539 "in response to %s%s", pl, smtp_command)
540 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
541 pl, smtp_command, s);
544 case ERRNO_FILTER_FAIL: /* Handle a failed filter process error;
545 can't send QUIT as we mustn't end the DATA. */
546 *message = string_sprintf("transport filter process failed (%d)%s",
548 more_errno == EX_EXECFAILED ? ": unable to execute command" : "");
551 case ERRNO_CHHEADER_FAIL: /* Handle a failed add_headers expansion;
552 can't send QUIT as we mustn't end the DATA. */
554 string_sprintf("failed to expand headers_add or headers_remove: %s",
555 expand_string_message);
558 case ERRNO_WRITEINCOMPLETE: /* failure to write a complete data block */
559 *message = string_sprintf("failed to write a data block");
563 case ERRNO_UTF8_FWD: /* no advertised SMTPUTF8, for international message */
564 *message = US"utf8 support required but not offered for forwarding";
565 DEBUG(D_deliver|D_transport) debug_printf("%s\n", *message);
570 /* Handle error responses from the remote mailer. */
574 *message = string_sprintf("SMTP error from remote mail server after %s%s: "
575 "%s", pl, smtp_command, s = string_printing(buffer));
576 *pass_message = TRUE;
581 /* No data was read. If there is no errno, this must be the EOF (i.e.
582 connection closed) case, which causes deferral. An explicit connection reset
583 error has the same effect. Otherwise, put the host's identity in the message,
584 leaving the errno value to be interpreted as well. In all cases, we have to
585 assume the connection is now dead. */
587 if (*errno_value == 0 || *errno_value == ECONNRESET)
589 *errno_value = ERRNO_SMTPCLOSED;
590 *message = US string_sprintf("Remote host closed connection "
591 "in response to %s%s", pl, smtp_command);
594 *message = US string_sprintf("%s [%s]", host->name, host->address);
601 /*************************************************
602 * Write error message to logs *
603 *************************************************/
605 /* This writes to the main log and to the message log.
608 addr the address item containing error information
609 host the current host
615 write_logs(address_item *addr, host_item *host)
617 uschar * message = LOGGING(outgoing_port)
618 ? string_sprintf("H=%s [%s]:%d", host->name, host->address,
619 host->port == PORT_NONE ? 25 : host->port)
620 : string_sprintf("H=%s [%s]", host->name, host->address);
624 message = string_sprintf("%s: %s", message, addr->message);
625 if (addr->basic_errno > 0)
626 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
627 log_write(0, LOG_MAIN, "%s", message);
628 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
632 const uschar * s = exim_errstr(addr->basic_errno);
633 log_write(0, LOG_MAIN, "%s %s", message, s);
634 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), message, s);
639 msglog_line(host_item * host, uschar * message)
641 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
642 host->name, host->address, message);
647 #ifndef DISABLE_EVENT
648 /*************************************************
649 * Post-defer action *
650 *************************************************/
652 /* This expands an arbitrary per-transport string.
653 It might, for example, be used to write to the database log.
656 addr the address item containing error information
657 host the current host
663 deferred_event_raise(address_item *addr, host_item *host)
665 uschar * action = addr->transport->event_action;
666 const uschar * save_domain;
672 save_domain = deliver_domain;
673 save_local = deliver_localpart;
675 /*XXX would ip & port already be set up? */
676 deliver_host_address = string_copy(host->address);
677 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
678 event_defer_errno = addr->basic_errno;
680 router_name = addr->router->name;
681 transport_name = addr->transport->name;
682 deliver_domain = addr->domain;
683 deliver_localpart = addr->local_part;
685 (void) event_raise(action, US"msg:host:defer",
687 ? addr->basic_errno > 0
688 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
689 : string_copy(addr->message)
690 : addr->basic_errno > 0
691 ? string_copy(US strerror(addr->basic_errno))
694 deliver_localpart = save_local;
695 deliver_domain = save_domain;
696 router_name = transport_name = NULL;
700 /*************************************************
701 * Synchronize SMTP responses *
702 *************************************************/
704 /* This function is called from smtp_deliver() to receive SMTP responses from
705 the server, and match them up with the commands to which they relate. When
706 PIPELINING is not in use, this function is called after every command, and is
707 therefore somewhat over-engineered, but it is simpler to use a single scheme
708 that works both with and without PIPELINING instead of having two separate sets
711 The set of commands that are buffered up with pipelining may start with MAIL
712 and may end with DATA; in between are RCPT commands that correspond to the
713 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
714 etc.) are never buffered.
716 Errors after MAIL or DATA abort the whole process leaving the response in the
717 buffer. After MAIL, pending responses are flushed, and the original command is
718 re-instated in big_buffer for error messages. For RCPT commands, the remote is
719 permitted to reject some recipient addresses while accepting others. However
720 certain errors clearly abort the whole process. Set the value in
721 transport_return to PENDING_OK if the address is accepted. If there is a
722 subsequent general error, it will get reset accordingly. If not, it will get
723 converted to OK at the end.
726 sx smtp connection context
727 count the number of responses to read
728 pending_DATA 0 if last command sent was not DATA
729 +1 if previously had a good recipient
730 -1 if not previously had a good recipient
732 Returns: 3 if at least one address had 2xx and one had 5xx
733 2 if at least one address had 5xx but none had 2xx
734 1 if at least one host had a 2xx response, but none had 5xx
735 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
736 -1 timeout while reading RCPT response
737 -2 I/O or other non-response error for RCPT
738 -3 DATA or MAIL failed - errno and buffer set
742 sync_responses(smtp_context * sx, int count, int pending_DATA)
744 address_item *addr = sx->sync_addr;
745 smtp_transport_options_block *ob =
746 (smtp_transport_options_block *)sx->tblock->options_block;
749 /* Handle the response for a MAIL command. On error, reinstate the original
750 command in big_buffer for error message use, and flush any further pending
751 responses before returning, except after I/O errors and timeouts. */
753 if (sx->pending_MAIL)
756 if (!smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
757 '2', ob->command_timeout))
759 DEBUG(D_transport) debug_printf("bad response for MAIL\n");
760 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
761 if (errno == 0 && sx->buffer[0] != 0)
763 uschar flushbuffer[4096];
765 if (sx->buffer[0] == '4')
767 save_errno = ERRNO_MAIL4XX;
768 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
772 if (!smtp_read_response(&sx->inblock, flushbuffer, sizeof(flushbuffer),
773 '2', ob->command_timeout)
774 && (errno != 0 || flushbuffer[0] == 0))
780 if (pending_DATA) count--; /* Number of RCPT responses to come */
781 while (count-- > 0) /* Mark any pending addrs with the host used */
783 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
784 addr->host_used = sx->host;
791 if (pending_DATA) count--; /* Number of RCPT responses to come */
793 /* Read and handle the required number of RCPT responses, matching each one up
794 with an address by scanning for the next address whose status is PENDING_DEFER.
799 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
801 /* The address was accepted */
802 addr->host_used = sx->host;
804 if (smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
805 '2', ob->command_timeout))
808 addr->transport_return = PENDING_OK;
810 /* If af_dr_retry_exists is set, there was a routing delay on this address;
811 ensure that any address-specific retry record is expunged. We do this both
812 for the basic key and for the version that also includes the sender. */
814 if (testflag(addr, af_dr_retry_exists))
816 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
818 retry_add_item(addr, altkey, rf_delete);
819 retry_add_item(addr, addr->address_retry_key, rf_delete);
823 /* Timeout while reading the response */
825 else if (errno == ETIMEDOUT)
827 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
828 transport_rcpt_address(addr, sx->tblock->rcpt_include_affixes));
829 set_errno_nohost(sx->first_addr, ETIMEDOUT, message, DEFER, FALSE);
830 retry_add_item(addr, addr->address_retry_key, 0);
831 update_waiting = FALSE;
835 /* Handle other errors in obtaining an SMTP response by returning -1. This
836 will cause all the addresses to be deferred. Restore the SMTP command in
837 big_buffer for which we are checking the response, so the error message
840 else if (errno != 0 || sx->buffer[0] == 0)
842 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
843 transport_rcpt_address(addr, sx->tblock->rcpt_include_affixes));
847 /* Handle SMTP permanent and temporary response codes. */
852 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
853 "%s", transport_rcpt_address(addr, sx->tblock->rcpt_include_affixes),
854 string_printing(sx->buffer));
855 setflag(addr, af_pass_message);
857 msglog_line(sx->host, addr->message);
859 /* The response was 5xx */
861 if (sx->buffer[0] == '5')
863 addr->transport_return = FAIL;
867 /* The response was 4xx */
871 addr->transport_return = DEFER;
872 addr->basic_errno = ERRNO_RCPT4XX;
873 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
877 #ifndef DISABLE_EVENT
878 event_defer_errno = addr->more_errno;
879 msg_event_raise(US"msg:rcpt:host:defer", addr);
882 /* Log temporary errors if there are more hosts to be tried.
883 If not, log this last one in the == line. */
886 log_write(0, LOG_MAIN, "H=%s [%s]: %s",
887 sx->host->name, sx->host->address, addr->message);
889 #ifndef DISABLE_EVENT
891 msg_event_raise(US"msg:rcpt:defer", addr);
894 /* Do not put this message on the list of those waiting for specific
895 hosts, as otherwise it is likely to be tried too often. */
897 update_waiting = FALSE;
899 /* Add a retry item for the address so that it doesn't get tried again
900 too soon. If address_retry_include_sender is true, add the sender address
904 ob->address_retry_include_sender
905 ? string_sprintf("%s:<%s>", addr->address_retry_key, sender_address)
906 : addr->address_retry_key,
911 } /* Loop for next RCPT response */
913 /* Update where to start at for the next block of responses, unless we
914 have already handled all the addresses. */
916 if (addr) sx->sync_addr = addr->next;
918 /* Handle a response to DATA. If we have not had any good recipients, either
919 previously or in this block, the response is ignored. */
921 if (pending_DATA != 0 &&
922 !smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
923 '3', ob->command_timeout))
928 if (pending_DATA > 0 || (yield & 1) != 0)
930 if (errno == 0 && sx->buffer[0] == '4')
932 errno = ERRNO_DATA4XX;
933 sx->first_addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
937 (void)check_response(sx->host, &errno, 0, sx->buffer, &code, &msg, &pass_message);
938 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
939 "is in use and there were no good recipients\n", msg);
942 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
943 present) received 3xx. If any RCPTs were handled and yielded anything other
944 than 4xx, yield will be set non-zero. */
951 /* Do the client side of smtp-level authentication */
954 buffer EHLO response from server (gets overwritten)
955 addrlist chain of potential addresses to deliver
956 host host to deliver to
958 ibp, obp comms channel control blocks
961 OK Success, or failed (but not required): global "smtp_authenticated" set
962 DEFER Failed authentication (and was required)
963 ERROR Internal problem
965 FAIL_SEND Failed communications - transmit
970 smtp_auth(uschar *buffer, unsigned bufsize, address_item *addrlist, host_item *host,
971 smtp_transport_options_block *ob, BOOL is_esmtp,
972 smtp_inblock *ibp, smtp_outblock *obp)
975 uschar *fail_reason = US"server did not advertise AUTH support";
977 smtp_authenticated = FALSE;
978 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
979 require_auth = verify_check_given_host(&ob->hosts_require_auth, host);
981 if (is_esmtp && !regex_AUTH) regex_AUTH =
982 regex_must_compile(US"\\n250[\\s\\-]AUTH\\s+([\\-\\w\\s]+)(?:\\n|$)",
985 if (is_esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
987 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
988 expand_nmax = -1; /* reset */
990 /* Must not do this check until after we have saved the result of the
991 regex match above. */
993 if (require_auth == OK ||
994 verify_check_given_host(&ob->hosts_try_auth, host) == OK)
997 fail_reason = US"no common mechanisms were found";
999 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1001 /* Scan the configured authenticators looking for one which is configured
1002 for use as a client, which is not suppressed by client_condition, and
1003 whose name matches an authentication mechanism supported by the server.
1004 If one is found, attempt to authenticate by calling its client function.
1007 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1011 (au->client_condition != NULL &&
1012 !expand_check_condition(au->client_condition, au->name,
1013 US"client authenticator")))
1015 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1017 (au->client)? "client_condition is false" :
1018 "not configured as a client");
1022 /* Loop to scan supported server mechanisms */
1027 int len = Ustrlen(au->public_name);
1028 while (isspace(*p)) p++;
1030 if (strncmpic(au->public_name, p, len) != 0 ||
1031 (p[len] != 0 && !isspace(p[len])))
1033 while (*p != 0 && !isspace(*p)) p++;
1037 /* Found data for a listed mechanism. Call its client entry. Set
1038 a flag in the outblock so that data is overwritten after sending so
1039 that reflections don't show it. */
1041 fail_reason = US"authentication attempt(s) failed";
1042 obp->authenticating = TRUE;
1043 rc = (au->info->clientcode)(au, ibp, obp,
1044 ob->command_timeout, buffer, bufsize);
1045 obp->authenticating = FALSE;
1046 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1049 /* A temporary authentication failure must hold up delivery to
1050 this host. After a permanent authentication failure, we carry on
1051 to try other authentication methods. If all fail hard, try to
1052 deliver the message unauthenticated unless require_auth was set. */
1057 smtp_authenticated = TRUE; /* stops the outer loop */
1058 client_authenticator = au->name;
1059 if (au->set_client_id != NULL)
1060 client_authenticated_id = expand_string(au->set_client_id);
1063 /* Failure after writing a command */
1068 /* Failure after reading a response */
1071 if (errno != 0 || buffer[0] != '5') return FAIL;
1072 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1073 au->name, host->name, host->address, buffer);
1076 /* Failure by some other means. In effect, the authenticator
1077 decided it wasn't prepared to handle this case. Typically this
1078 is the result of "fail" in an expansion string. Do we need to
1079 log anything here? Feb 2006: a message is now put in the buffer
1080 if logging is required. */
1084 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1085 "authentication H=%s [%s] %s", au->name, host->name,
1086 host->address, buffer);
1089 /* Internal problem, message in buffer. */
1092 set_errno_nohost(addrlist, ERRNO_AUTHPROB, string_copy(buffer),
1097 break; /* If not authenticated, try next authenticator */
1098 } /* Loop for scanning supported server mechanisms */
1099 } /* Loop for further authenticators */
1103 /* If we haven't authenticated, but are required to, give up. */
1105 if (require_auth == OK && !smtp_authenticated)
1107 set_errno_nohost(addrlist, ERRNO_AUTHFAIL,
1108 string_sprintf("authentication required but %s", fail_reason), DEFER,
1117 /* Construct AUTH appendix string for MAIL TO */
1120 buffer to build string
1121 addrlist chain of potential addresses to deliver
1122 ob transport options
1124 Globals smtp_authenticated
1125 client_authenticated_sender
1126 Return True on error, otherwise buffer has (possibly empty) terminated string
1130 smtp_mail_auth_str(uschar *buffer, unsigned bufsize, address_item *addrlist,
1131 smtp_transport_options_block *ob)
1133 uschar *local_authenticated_sender = authenticated_sender;
1136 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n", authenticated_sender, ob->authenticated_sender, smtp_authenticated?"Y":"N");
1139 if (ob->authenticated_sender != NULL)
1141 uschar *new = expand_string(ob->authenticated_sender);
1144 if (!expand_string_forcedfail)
1146 uschar *message = string_sprintf("failed to expand "
1147 "authenticated_sender: %s", expand_string_message);
1148 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1152 else if (new[0] != 0) local_authenticated_sender = new;
1155 /* Add the authenticated sender address if present */
1157 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1158 local_authenticated_sender != NULL)
1160 string_format(buffer, bufsize, " AUTH=%s",
1161 auth_xtextencode(local_authenticated_sender,
1162 Ustrlen(local_authenticated_sender)));
1163 client_authenticated_sender = string_copy(local_authenticated_sender);
1173 #ifdef EXPERIMENTAL_DANE
1174 /* Lookup TLSA record for host/port.
1175 Return: OK success with dnssec; DANE mode
1176 DEFER Do not use this host now, may retry later
1177 FAIL_FORCED No TLSA record; DANE not usable
1178 FAIL Do not use this connection
1182 tlsa_lookup(const host_item * host, dns_answer * dnsa, BOOL dane_required)
1184 /* move this out to host.c given the similarity to dns_lookup() ? */
1186 const uschar * fullname = buffer;
1188 /* TLSA lookup string */
1189 (void)sprintf(CS buffer, "_%d._tcp.%.256s", host->port, host->name);
1191 switch (dns_lookup(dnsa, buffer, T_TLSA, &fullname))
1194 if (!dns_is_secure(dnsa))
1196 log_write(0, LOG_MAIN, "DANE error: TLSA lookup not DNSSEC");
1202 return DEFER; /* just defer this TLS'd conn */
1204 case DNS_NODATA: /* no TLSA RR for this lookup */
1205 case DNS_NOMATCH: /* no records at all for this lookup */
1206 return dane_required ? FAIL : FAIL_FORCED;
1210 return dane_required ? FAIL : DEFER;
1217 typedef struct smtp_compare_s
1219 uschar *current_sender_address;
1220 struct transport_instance *tblock;
1224 /* Create a unique string that identifies this message, it is based on
1225 sender_address, helo_data and tls_certificate if enabled.
1229 smtp_local_identity(uschar * sender, struct transport_instance * tblock)
1231 address_item * addr1;
1232 uschar * if1 = US"";
1233 uschar * helo1 = US"";
1235 uschar * tlsc1 = US"";
1237 uschar * save_sender_address = sender_address;
1238 uschar * local_identity = NULL;
1239 smtp_transport_options_block * ob =
1240 (smtp_transport_options_block *)tblock->options_block;
1242 sender_address = sender;
1244 addr1 = deliver_make_addr (sender, TRUE);
1245 deliver_set_expansions(addr1);
1248 if1 = expand_string(ob->interface);
1251 helo1 = expand_string(ob->helo_data);
1254 if (ob->tls_certificate)
1255 tlsc1 = expand_string(ob->tls_certificate);
1256 local_identity = string_sprintf ("%s^%s^%s", if1, helo1, tlsc1);
1258 local_identity = string_sprintf ("%s^%s", if1, helo1);
1261 deliver_set_expansions(NULL);
1262 sender_address = save_sender_address;
1264 return local_identity;
1269 /* This routine is a callback that is called from transport_check_waiting.
1270 This function will evaluate the incoming message versus the previous
1271 message. If the incoming message is using a different local identity then
1272 we will veto this new message. */
1275 smtp_are_same_identities(uschar * message_id, smtp_compare_t * s_compare)
1277 uschar * message_local_identity,
1278 * current_local_identity,
1279 * new_sender_address;
1281 current_local_identity =
1282 smtp_local_identity(s_compare->current_sender_address, s_compare->tblock);
1284 if (!(new_sender_address = deliver_get_sender_address(message_id)))
1287 message_local_identity =
1288 smtp_local_identity(new_sender_address, s_compare->tblock);
1290 return Ustrcmp(current_local_identity, message_local_identity) == 0;
1296 ehlo_response(uschar * buf, uschar checks)
1298 size_t bsize = Ustrlen(buf);
1301 if ( checks & PEER_OFFERED_TLS
1302 && pcre_exec(regex_STARTTLS, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1303 checks &= ~PEER_OFFERED_TLS;
1306 if ( checks & PEER_OFFERED_IGNQ
1307 && pcre_exec(regex_IGNOREQUOTA, NULL, CS buf, bsize, 0,
1308 PCRE_EOPT, NULL, 0) < 0)
1309 checks &= ~PEER_OFFERED_IGNQ;
1311 if ( checks & PEER_OFFERED_CHUNKING
1312 && pcre_exec(regex_CHUNKING, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1313 checks &= ~PEER_OFFERED_CHUNKING;
1315 #ifndef DISABLE_PRDR
1316 if ( checks & PEER_OFFERED_PRDR
1317 && pcre_exec(regex_PRDR, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1318 checks &= ~PEER_OFFERED_PRDR;
1322 if ( checks & PEER_OFFERED_UTF8
1323 && pcre_exec(regex_UTF8, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1324 checks &= ~PEER_OFFERED_UTF8;
1327 if ( checks & PEER_OFFERED_DSN
1328 && pcre_exec(regex_DSN, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1329 checks &= ~PEER_OFFERED_DSN;
1331 if ( checks & PEER_OFFERED_PIPE
1332 && pcre_exec(regex_PIPELINING, NULL, CS buf, bsize, 0,
1333 PCRE_EOPT, NULL, 0) < 0)
1334 checks &= ~PEER_OFFERED_PIPE;
1336 if ( checks & PEER_OFFERED_SIZE
1337 && pcre_exec(regex_SIZE, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1338 checks &= ~PEER_OFFERED_SIZE;
1345 /* Callback for emitting a BDAT data chunk header.
1347 If given a nonzero size, first flush any buffered SMTP commands
1348 then emit the command.
1350 Reap previous SMTP command responses if requested, and always reap
1351 the response from a previous BDAT command.
1354 tctx transport context
1355 chunk_size value for SMTP BDAT command
1357 tc_chunk_last add LAST option to SMTP BDAT command
1358 tc_reap_prev reap response to previous SMTP commands
1360 Returns: OK or ERROR
1364 smtp_chunk_cmd_callback(transport_ctx * tctx, unsigned chunk_size,
1367 smtp_transport_options_block * ob =
1368 (smtp_transport_options_block *)(tctx->tblock->options_block);
1369 smtp_context * sx = tctx->smtp_context;
1373 /* Write SMTP chunk header command */
1377 if((cmd_count = smtp_write_command(&sx->outblock, FALSE, "BDAT %u%s\r\n",
1379 flags & tc_chunk_last ? " LAST" : "")
1380 ) < 0) return ERROR;
1381 if (flags & tc_chunk_last)
1382 data_command = string_copy(big_buffer); /* Save for later error message */
1385 prev_cmd_count = cmd_count += sx->cmd_count;
1387 /* Reap responses for any previous, but not one we just emitted */
1391 if (sx->pending_BDAT)
1394 if (flags & tc_reap_prev && prev_cmd_count > 0)
1396 DEBUG(D_transport) debug_printf("look for %d responses"
1397 " for previous pipelined cmds\n", prev_cmd_count);
1399 switch(sync_responses(sx, prev_cmd_count, 0))
1401 case 1: /* 2xx (only) => OK */
1402 case 3: sx->good_RCPT = TRUE; /* 2xx & 5xx => OK & progress made */
1403 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
1404 case 0: break; /* No 2xx or 5xx, but no probs */
1406 case -1: /* Timeout on RCPT */
1407 default: return ERROR; /* I/O error, or any MAIL/DATA error */
1410 if (!sx->pending_BDAT)
1411 pipelining_active = FALSE;
1414 /* Reap response for an outstanding BDAT */
1416 if (sx->pending_BDAT)
1418 DEBUG(D_transport) debug_printf("look for one response for BDAT\n");
1420 if (!smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer), '2',
1421 ob->command_timeout))
1423 if (errno == 0 && sx->buffer[0] == '4')
1425 errno = ERRNO_DATA4XX; /*XXX does this actually get used? */
1426 sx->addrlist->more_errno |=
1427 ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1432 sx->pending_BDAT = FALSE;
1433 pipelining_active = FALSE;
1435 else if (chunk_size > 0)
1436 sx->pending_BDAT = TRUE;
1439 sx->cmd_count = cmd_count;
1445 /*************************************************
1446 * Make connection for given message *
1447 *************************************************/
1451 ctx connection context
1452 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1453 a second attempt after TLS initialization fails
1455 Returns: OK - the connection was made and the delivery attempted;
1456 fd is set in the conn context, tls_out set up.
1457 DEFER - the connection could not be made, or something failed
1458 while setting up the SMTP session, or there was a
1459 non-message-specific error, such as a timeout.
1460 ERROR - helo_data or add_headers or authenticated_sender is
1461 specified for this transport, and the string failed
1465 smtp_setup_conn(smtp_context * sx, BOOL suppress_tls)
1467 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1468 dns_answer tlsa_dnsa;
1470 BOOL pass_message = FALSE;
1471 uschar * message = NULL;
1475 sx->ob = (smtp_transport_options_block *) sx->tblock->options_block;
1477 sx->lmtp = strcmpic(sx->ob->protocol, US"lmtp") == 0;
1478 sx->smtps = strcmpic(sx->ob->protocol, US"smtps") == 0;
1480 sx->send_rset = TRUE;
1481 sx->send_quit = TRUE;
1482 sx->setting_up = TRUE;
1484 sx->esmtp_sent = FALSE;
1486 sx->utf8_needed = FALSE;
1488 sx->dsn_all_lasthop = TRUE;
1489 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1491 sx->dane_required = verify_check_given_host(&sx->ob->hosts_require_dane, sx->host) == OK;
1494 if ((sx->max_rcpt = sx->tblock->max_addresses) == 0) sx->max_rcpt = 999999;
1495 sx->peer_offered = 0;
1496 sx->igquotstr = US"";
1497 if (!sx->helo_data) sx->helo_data = sx->ob->helo_data;
1498 #ifdef EXPERIMENTAL_DSN_INFO
1499 sx->smtp_greeting = NULL;
1500 sx->helo_response = NULL;
1503 smtp_command = US"initial connection";
1504 sx->buffer[0] = '\0';
1506 /* Set up the buffer for reading SMTP response packets. */
1508 sx->inblock.buffer = sx->inbuffer;
1509 sx->inblock.buffersize = sizeof(sx->inbuffer);
1510 sx->inblock.ptr = sx->inbuffer;
1511 sx->inblock.ptrend = sx->inbuffer;
1513 /* Set up the buffer for holding SMTP commands while pipelining */
1515 sx->outblock.buffer = sx->outbuffer;
1516 sx->outblock.buffersize = sizeof(sx->outbuffer);
1517 sx->outblock.ptr = sx->outbuffer;
1518 sx->outblock.cmd_count = 0;
1519 sx->outblock.authenticating = FALSE;
1521 /* Reset the parameters of a TLS session. */
1524 tls_out.cipher = NULL; /* the one we may use for this transport */
1525 tls_out.ourcert = NULL;
1526 tls_out.peercert = NULL;
1527 tls_out.peerdn = NULL;
1528 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1531 tls_out.ocsp = OCSP_NOT_REQ;
1533 /* Flip the legacy TLS-related variables over to the outbound set in case
1534 they're used in the context of the transport. Don't bother resetting
1535 afterward (when being used by a transport) as we're in a subprocess.
1536 For verify, unflipped once the callout is dealt with */
1538 tls_modify_variables(&tls_out);
1543 set_errno_nohost(sx->addrlist, ERRNO_TLSFAILURE, US"TLS support not available",
1549 /* Make a connection to the host if this isn't a continued delivery, and handle
1550 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
1551 specially so they can be identified for retries. */
1553 if (continue_hostname == NULL)
1556 HDEBUG(D_verify) debug_printf("interface=%s port=%d\n", sx->interface, sx->port);
1558 /* This puts port into host->port */
1559 sx->inblock.sock = sx->outblock.sock =
1560 smtp_connect(sx->host, sx->host_af, sx->port, sx->interface,
1561 sx->ob->connect_timeout, sx->tblock);
1563 if (sx->inblock.sock < 0)
1565 uschar * msg = NULL;
1568 msg = US strerror(errno);
1569 HDEBUG(D_verify) debug_printf("connect: %s\n", msg);
1571 set_errno_nohost(sx->addrlist,
1572 errno == ETIMEDOUT ? ERRNO_CONNECTTIMEOUT : errno,
1573 sx->verify ? string_sprintf("could not connect: %s", msg)
1576 sx->send_quit = FALSE;
1580 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1582 tls_out.dane_verified = FALSE;
1583 tls_out.tlsa_usage = 0;
1585 if (sx->host->dnssec == DS_YES)
1587 if( sx->dane_required
1588 || verify_check_given_host(&sx->ob->hosts_try_dane, sx->host) == OK
1590 switch (rc = tlsa_lookup(sx->host, &tlsa_dnsa, sx->dane_required))
1592 case OK: sx->dane = TRUE; break;
1593 case FAIL_FORCED: break;
1594 default: set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
1595 string_sprintf("DANE error: tlsa lookup %s",
1596 rc == DEFER ? "DEFER" : "FAIL"),
1601 else if (sx->dane_required)
1603 set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
1604 string_sprintf("DANE error: %s lookup not DNSSEC", sx->host->name),
1610 sx->ob->tls_tempfail_tryclear = FALSE;
1614 /* Expand the greeting message while waiting for the initial response. (Makes
1615 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1616 delayed till here so that $sending_interface and $sending_port are set. */
1619 if (!(sx->helo_data = expand_string(sx->helo_data)))
1621 log_write(0, LOG_MAIN|LOG_PANIC,
1622 "<%s>: failed to expand transport's helo_data value for callout: %s",
1623 sx->addrlist->address, expand_string_message);
1628 expand_string_message = NULL;
1629 if ((sx->helo_data = string_domain_utf8_to_alabel(sx->helo_data,
1630 &expand_string_message)),
1631 expand_string_message)
1633 log_write(0, LOG_MAIN|LOG_PANIC,
1634 "<%s>: failed to expand transport's helo_data value for callout: %s",
1635 sx->addrlist->address, expand_string_message);
1637 sx->helo_data = NULL;
1641 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1642 is nevertheless a reasonably clean way of programming this kind of logic,
1643 where you want to escape on any error. */
1650 (void) setsockopt(sx->inblock.sock, IPPROTO_TCP, TCP_QUICKACK, US &off, sizeof(off));
1652 good_response = smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
1653 '2', sx->ob->command_timeout);
1654 #ifdef EXPERIMENTAL_DSN_INFO
1655 sx->smtp_greeting = string_copy(sx->buffer);
1657 if (!good_response) goto RESPONSE_FAILED;
1659 #ifndef DISABLE_EVENT
1662 lookup_dnssec_authenticated = sx->host->dnssec==DS_YES ? US"yes"
1663 : sx->host->dnssec==DS_NO ? US"no" : NULL;
1664 s = event_raise(sx->tblock->event_action, US"smtp:connect", sx->buffer);
1667 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL,
1668 string_sprintf("deferred by smtp:connect event expansion: %s", s),
1676 /* Now check if the helo_data expansion went well, and sign off cleanly if
1681 message = string_sprintf("failed to expand helo_data: %s",
1682 expand_string_message);
1683 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1689 /** Debugging without sending a message
1690 sx->addrlist->transport_return = DEFER;
1694 /* Errors that occur after this point follow an SMTP command, which is
1695 left in big_buffer by smtp_write_command() for use in error messages. */
1697 smtp_command = big_buffer;
1699 /* Tell the remote who we are...
1701 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1702 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1703 greeting is of this form. The assumption was that the far end supports it
1704 properly... but experience shows that there are some that give 5xx responses,
1705 even though the banner includes "ESMTP" (there's a bloody-minded one that
1706 says "ESMTP not spoken here"). Cope with that case.
1708 September 2000: Time has passed, and it seems reasonable now to always send
1709 EHLO at the start. It is also convenient to make the change while installing
1712 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1713 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1714 would be no way to send out the mails, so there is now a host list
1715 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1716 PIPELINING problem as well. Maybe it can also be useful to cure other
1717 problems with broken servers.
1719 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1720 Then somebody tried it with a Microsoft mailer... It seems that all other
1721 mailers use upper case for some reason (the RFC is quite clear about case
1722 independence) so, for peace of mind, I gave in. */
1724 sx->esmtp = verify_check_given_host(&sx->ob->hosts_avoid_esmtp, sx->host) != OK;
1726 /* Alas; be careful, since this goto is not an error-out, so conceivably
1727 we might set data between here and the target which we assume to exist
1728 and be usable. I can see this coming back to bite us. */
1732 smtp_peer_options |= PEER_OFFERED_TLS;
1733 suppress_tls = FALSE;
1734 sx->ob->tls_tempfail_tryclear = FALSE;
1735 smtp_command = US"SSL-on-connect";
1742 if (smtp_write_command(&sx->outblock, FALSE, "%s %s\r\n",
1743 sx->lmtp ? "LHLO" : "EHLO", sx->helo_data) < 0)
1745 sx->esmtp_sent = TRUE;
1746 if (!smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer), '2',
1747 sx->ob->command_timeout))
1749 if (errno != 0 || sx->buffer[0] == 0 || sx->lmtp)
1751 #ifdef EXPERIMENTAL_DSN_INFO
1752 sx->helo_response = string_copy(sx->buffer);
1754 goto RESPONSE_FAILED;
1758 #ifdef EXPERIMENTAL_DSN_INFO
1759 sx->helo_response = string_copy(sx->buffer);
1764 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1769 int n = sizeof(sx->buffer);
1770 uschar * rsp = sx->buffer;
1772 if (sx->esmtp_sent && (n = Ustrlen(sx->buffer)) < sizeof(sx->buffer)/2)
1773 { rsp = sx->buffer + n + 1; n = sizeof(sx->buffer) - n; }
1775 if (smtp_write_command(&sx->outblock, FALSE, "HELO %s\r\n", sx->helo_data) < 0)
1777 good_response = smtp_read_response(&sx->inblock, rsp, n,
1778 '2', sx->ob->command_timeout);
1779 #ifdef EXPERIMENTAL_DSN_INFO
1780 sx->helo_response = string_copy(rsp);
1784 /* Handle special logging for a closed connection after HELO
1785 when had previously sent EHLO */
1787 if (rsp != sx->buffer && rsp[0] == 0 && (errno == 0 || errno == ECONNRESET))
1789 errno = ERRNO_SMTPCLOSED;
1790 goto EHLOHELO_FAILED;
1792 Ustrncpy(sx->buffer, rsp, sizeof(sx->buffer)/2);
1793 goto RESPONSE_FAILED;
1797 sx->peer_offered = smtp_peer_options = 0;
1799 if (sx->esmtp || sx->lmtp)
1801 sx->peer_offered = ehlo_response(sx->buffer,
1802 PEER_OFFERED_TLS /* others checked later */
1805 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1808 smtp_peer_options |= sx->peer_offered & PEER_OFFERED_TLS;
1813 /* For continuing deliveries down the same channel, having re-exec'd the socket
1814 is the standard input; for a socket held open from verify it is recorded
1815 in the cutthrough context block. Either way we don't need to redo EHLO here
1816 (but may need to do so for TLS - see below).
1817 Set up the pointer to where subsequent commands will be left, for
1818 error messages. Note that smtp_peer_options will have been
1819 set from the command line if they were set in the process that passed the
1822 /*XXX continue case needs to propagate DSN_INFO, prob. in deliver.c
1823 as the continue goes via transport_pass_socket() and doublefork and exec.
1824 It does not wait. Unclear how we keep separate host's responses
1825 separate - we could match up by host ip+port as a bodge. */
1829 if (cutthrough.fd >= 0 && cutthrough.callout_hold_only)
1831 sx->inblock.sock = sx->outblock.sock = cutthrough.fd;
1832 sx->host->port = sx->port = cutthrough.host.port;
1836 sx->inblock.sock = sx->outblock.sock = 0; /* stdin */
1837 sx->host->port = sx->port; /* Record the port that was used */
1839 smtp_command = big_buffer;
1840 sx->helo_data = NULL; /* ensure we re-expand ob->helo_data */
1842 /* For a continued connection with TLS being proxied for us, or a
1843 held-open verify connection with TLS, nothing more to do. */
1845 if ( continue_proxy_cipher
1846 || (cutthrough.fd >= 0 && cutthrough.callout_hold_only && cutthrough.is_tls)
1849 sx->peer_offered = smtp_peer_options;
1850 pipelining_active = !!(smtp_peer_options & PEER_OFFERED_PIPE);
1851 HDEBUG(D_transport) debug_printf("continued connection, %s TLS\n",
1852 continue_proxy_cipher ? "proxied" : "verify conn with");
1855 HDEBUG(D_transport) debug_printf("continued connection, no TLS\n");
1858 /* If TLS is available on this connection, whether continued or not, attempt to
1859 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1860 send another EHLO - the server may give a different answer in secure mode. We
1861 use a separate buffer for reading the response to STARTTLS so that if it is
1862 negative, the original EHLO data is available for subsequent analysis, should
1863 the client not be required to use TLS. If the response is bad, copy the buffer
1864 for error analysis. */
1867 if ( smtp_peer_options & PEER_OFFERED_TLS
1869 && verify_check_given_host(&sx->ob->hosts_avoid_tls, sx->host) != OK
1871 || verify_check_given_host(&sx->ob->hosts_verify_avoid_tls, sx->host) != OK
1874 uschar buffer2[4096];
1875 if (smtp_write_command(&sx->outblock, FALSE, "STARTTLS\r\n") < 0)
1878 /* If there is an I/O error, transmission of this message is deferred. If
1879 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1880 false, we also defer. However, if there is a temporary rejection of STARTTLS
1881 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1882 STARTTLS, we carry on. This means we will try to send the message in clear,
1883 unless the host is in hosts_require_tls (tested below). */
1885 if (!smtp_read_response(&sx->inblock, buffer2, sizeof(buffer2), '2',
1886 sx->ob->command_timeout))
1890 || (buffer2[0] == '4' && !sx->ob->tls_tempfail_tryclear)
1893 Ustrncpy(sx->buffer, buffer2, sizeof(sx->buffer));
1894 sx->buffer[sizeof(sx->buffer)-1] = '\0';
1895 goto RESPONSE_FAILED;
1899 /* STARTTLS accepted: try to negotiate a TLS session. */
1904 address_item * addr;
1906 int rc = tls_client_start(sx->inblock.sock, sx->host, sx->addrlist, sx->tblock,
1907 # ifdef EXPERIMENTAL_DANE
1908 sx->dane ? &tlsa_dnsa : NULL,
1912 /* TLS negotiation failed; give an error. From outside, this function may
1913 be called again to try in clear on a new connection, if the options permit
1914 it for this host. */
1918 # ifdef EXPERIMENTAL_DANE
1919 if (sx->dane) log_write(0, LOG_MAIN,
1920 "DANE attempt failed; TLS connection to %s [%s]: %s",
1921 sx->host->name, sx->host->address, errstr);
1924 errno = ERRNO_TLSFAILURE;
1925 message = string_sprintf("TLS session: %s", errstr);
1926 sx->send_quit = FALSE;
1930 /* TLS session is set up */
1932 smtp_peer_options_wrap = smtp_peer_options;
1933 for (addr = sx->addrlist; addr; addr = addr->next)
1934 if (addr->transport_return == PENDING_DEFER)
1936 addr->cipher = tls_out.cipher;
1937 addr->ourcert = tls_out.ourcert;
1938 addr->peercert = tls_out.peercert;
1939 addr->peerdn = tls_out.peerdn;
1940 addr->ocsp = tls_out.ocsp;
1945 /* if smtps, we'll have smtp_command set to something else; always safe to
1947 smtp_command = big_buffer;
1949 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1950 helo_data is null, we are dealing with a connection that was passed from
1951 another process, and so we won't have expanded helo_data above. We have to
1952 expand it here. $sending_ip_address and $sending_port are set up right at the
1953 start of the Exim process (in exim.c). */
1955 if (tls_out.active >= 0)
1960 if (!sx->helo_data && !(sx->helo_data = expand_string(sx->ob->helo_data)))
1962 uschar *message = string_sprintf("failed to expand helo_data: %s",
1963 expand_string_message);
1964 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1969 /* For SMTPS we need to wait for the initial OK response. */
1972 good_response = smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
1973 '2', sx->ob->command_timeout);
1974 #ifdef EXPERIMENTAL_DSN_INFO
1975 sx->smtp_greeting = string_copy(sx->buffer);
1977 if (!good_response) goto RESPONSE_FAILED;
1981 greeting_cmd = "EHLO";
1984 greeting_cmd = "HELO";
1986 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1989 if (smtp_write_command(&sx->outblock, FALSE, "%s %s\r\n",
1990 sx->lmtp ? "LHLO" : greeting_cmd, sx->helo_data) < 0)
1992 good_response = smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
1993 '2', sx->ob->command_timeout);
1994 #ifdef EXPERIMENTAL_DSN_INFO
1995 sx->helo_response = string_copy(sx->buffer);
1997 if (!good_response) goto RESPONSE_FAILED;
1998 smtp_peer_options = 0;
2001 /* If the host is required to use a secure channel, ensure that we
2005 # ifdef EXPERIMENTAL_DANE
2008 || verify_check_given_host(&sx->ob->hosts_require_tls, sx->host) == OK
2011 errno = ERRNO_TLSREQUIRED;
2012 message = string_sprintf("a TLS session is required, but %s",
2013 smtp_peer_options & PEER_OFFERED_TLS
2014 ? "an attempt to start TLS failed" : "the server did not offer TLS support");
2017 #endif /*SUPPORT_TLS*/
2019 /* If TLS is active, we have just started it up and re-done the EHLO command,
2020 so its response needs to be analyzed. If TLS is not active and this is a
2021 continued session down a previously-used socket, we haven't just done EHLO, so
2024 if (continue_hostname == NULL
2026 || tls_out.active >= 0
2030 if (sx->esmtp || sx->lmtp)
2032 sx->peer_offered = ehlo_response(sx->buffer,
2034 | (sx->lmtp && sx->ob->lmtp_ignore_quota ? PEER_OFFERED_IGNQ : 0)
2035 | PEER_OFFERED_CHUNKING
2038 | (sx->addrlist->prop.utf8_msg ? PEER_OFFERED_UTF8 : 0)
2039 /*XXX if we hand peercaps on to continued-conn processes,
2040 must not depend on this addr */
2044 | (sx->ob->size_addition >= 0 ? PEER_OFFERED_SIZE : 0)
2047 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
2048 lmtp_ignore_quota option was set. */
2050 sx->igquotstr = sx->peer_offered & PEER_OFFERED_IGNQ ? US" IGNOREQUOTA" : US"";
2052 /* If the response to EHLO specified support for the SIZE parameter, note
2053 this, provided size_addition is non-negative. */
2055 smtp_peer_options |= sx->peer_offered & PEER_OFFERED_SIZE;
2057 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
2058 the current host, esmtp will be false, so PIPELINING can never be used. If
2059 the current host matches hosts_avoid_pipelining, don't do it. */
2061 if ( sx->peer_offered & PEER_OFFERED_PIPE
2062 && verify_check_given_host(&sx->ob->hosts_avoid_pipelining, sx->host) != OK)
2063 smtp_peer_options |= PEER_OFFERED_PIPE;
2065 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
2066 smtp_peer_options & PEER_OFFERED_PIPE ? "" : "not ");
2068 if ( sx->peer_offered & PEER_OFFERED_CHUNKING
2069 && verify_check_given_host(&sx->ob->hosts_try_chunking, sx->host) != OK)
2070 sx->peer_offered &= ~PEER_OFFERED_CHUNKING;
2072 if (sx->peer_offered & PEER_OFFERED_CHUNKING)
2073 {DEBUG(D_transport) debug_printf("CHUNKING usable\n");}
2075 #ifndef DISABLE_PRDR
2076 if ( sx->peer_offered & PEER_OFFERED_PRDR
2077 && verify_check_given_host(&sx->ob->hosts_try_prdr, sx->host) != OK)
2078 sx->peer_offered &= ~PEER_OFFERED_PRDR;
2080 if (sx->peer_offered & PEER_OFFERED_PRDR)
2081 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
2084 /* Note if the server supports DSN */
2085 smtp_peer_options |= sx->peer_offered & PEER_OFFERED_DSN;
2086 DEBUG(D_transport) debug_printf("%susing DSN\n",
2087 sx->peer_offered & PEER_OFFERED_DSN ? "" : "not ");
2089 /* Note if the response to EHLO specifies support for the AUTH extension.
2090 If it has, check that this host is one we want to authenticate to, and do
2091 the business. The host name and address must be available when the
2092 authenticator's client driver is running. */
2094 switch (yield = smtp_auth(sx->buffer, sizeof(sx->buffer), sx->addrlist, sx->host,
2095 sx->ob, sx->esmtp, &sx->inblock, &sx->outblock))
2097 default: goto SEND_QUIT;
2099 case FAIL_SEND: goto SEND_FAILED;
2100 case FAIL: goto RESPONSE_FAILED;
2104 pipelining_active = !!(smtp_peer_options & PEER_OFFERED_PIPE);
2106 /* The setting up of the SMTP call is now complete. Any subsequent errors are
2107 message-specific. */
2109 sx->setting_up = FALSE;
2112 if (sx->addrlist->prop.utf8_msg)
2114 sx->utf8_needed = !sx->addrlist->prop.utf8_downcvt
2115 && !sx->addrlist->prop.utf8_downcvt_maybe;
2116 DEBUG(D_transport) if (!sx->utf8_needed)
2117 debug_printf("utf8: %s downconvert\n",
2118 sx->addrlist->prop.utf8_downcvt ? "mandatory" : "optional");
2121 /* If this is an international message we need the host to speak SMTPUTF8 */
2122 if (sx->utf8_needed && !(sx->peer_offered & PEER_OFFERED_UTF8))
2124 errno = ERRNO_UTF8_FWD;
2125 goto RESPONSE_FAILED;
2137 sx->send_quit = check_response(sx->host, &errno, sx->addrlist->more_errno,
2138 sx->buffer, &code, &message, &pass_message);
2143 message = US string_sprintf("send() to %s [%s] failed: %s",
2144 sx->host->name, sx->host->address, strerror(errno));
2145 sx->send_quit = FALSE;
2148 /* This label is jumped to directly when a TLS negotiation has failed,
2149 or was not done for a host for which it is required. Values will be set
2150 in message and errno, and setting_up will always be true. Treat as
2151 a temporary error. */
2155 message = string_sprintf("Remote host closed connection in response to %s"
2156 " (EHLO response was: %s)", smtp_command, sx->buffer);
2157 sx->send_quit = FALSE;
2166 /* The failure happened while setting up the call; see if the failure was
2167 a 5xx response (this will either be on connection, or following HELO - a 5xx
2168 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
2169 never going to accept them. For other errors during setting up (timeouts or
2170 whatever), defer all addresses, and yield DEFER, so that the host is not
2171 tried again for a while. */
2174 sx->ok = FALSE; /* For when reached by GOTO */
2178 || errno == ERRNO_UTF8_FWD
2182 set_errno(sx->addrlist, errno, message, yield, pass_message, sx->host
2183 #ifdef EXPERIMENTAL_DSN_INFO
2184 , sx->smtp_greeting, sx->helo_response
2193 (void)smtp_write_command(&sx->outblock, FALSE, "QUIT\r\n");
2196 tls_close(FALSE, TRUE);
2199 /* Close the socket, and return the appropriate value, first setting
2200 works because the NULL setting is passed back to the calling process, and
2201 remote_max_parallel is forced to 1 when delivering over an existing connection,
2203 If all went well and continue_more is set, we shouldn't actually get here if
2204 there are further addresses, as the return above will be taken. However,
2205 writing RSET might have failed, or there may be other addresses whose hosts are
2206 specified in the transports, and therefore not visible at top level, in which
2207 case continue_more won't get set. */
2209 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
2212 shutdown(sx->outblock.sock, SHUT_WR);
2213 if (fcntl(sx->inblock.sock, F_SETFL, O_NONBLOCK) == 0)
2214 for (rc = 16; read(sx->inblock.sock, sx->inbuffer, sizeof(sx->inbuffer)) > 0 && rc > 0;)
2215 rc--; /* drain socket */
2216 sx->send_quit = FALSE;
2218 (void)close(sx->inblock.sock);
2219 sx->inblock.sock = sx->outblock.sock = -1;
2221 #ifndef DISABLE_EVENT
2222 (void) event_raise(sx->tblock->event_action, US"tcp:close", NULL);
2225 continue_transport = NULL;
2226 continue_hostname = NULL;
2233 /* Create the string of options that will be appended to the MAIL FROM:
2234 in the connection context buffer */
2237 build_mailcmd_options(smtp_context * sx, address_item * addrlist)
2239 uschar * p = sx->buffer;
2240 address_item * addr;
2245 /* If we know the receiving MTA supports the SIZE qualification,
2246 send it, adding something to the message size to allow for imprecision
2247 and things that get added en route. Exim keeps the number of lines
2248 in a message, so we can give an accurate value for the original message, but we
2249 need some additional to handle added headers. (Double "." characters don't get
2250 included in the count.) */
2252 if (sx->peer_offered & PEER_OFFERED_SIZE)
2254 sprintf(CS p, " SIZE=%d", message_size+message_linecount+sx->ob->size_addition);
2258 #ifndef DISABLE_PRDR
2259 /* If it supports Per-Recipient Data Reponses, and we have omre than one recipient,
2262 sx->prdr_active = FALSE;
2263 if (sx->peer_offered & PEER_OFFERED_PRDR)
2264 for (addr = addrlist; addr; addr = addr->next)
2265 if (addr->transport_return == PENDING_DEFER)
2267 for (addr = addr->next; addr; addr = addr->next)
2268 if (addr->transport_return == PENDING_DEFER)
2269 { /* at least two recipients to send */
2270 sx->prdr_active = TRUE;
2271 sprintf(CS p, " PRDR"); p += 5;
2279 /* If it supports internationalised messages, and this meesage need that,
2282 if ( sx->peer_offered & PEER_OFFERED_UTF8
2283 && addrlist->prop.utf8_msg
2284 && !addrlist->prop.utf8_downcvt
2286 Ustrcpy(p, " SMTPUTF8"), p += 9;
2289 /* check if all addresses have DSN-lasthop flag; do not send RET and ENVID if so */
2290 for (sx->dsn_all_lasthop = TRUE, addr = addrlist, address_count = 0;
2291 addr && address_count < sx->max_rcpt;
2292 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
2295 if (!(addr->dsn_flags & rf_dsnlasthop))
2297 sx->dsn_all_lasthop = FALSE;
2302 /* Add any DSN flags to the mail command */
2304 if (sx->peer_offered & PEER_OFFERED_DSN && !sx->dsn_all_lasthop)
2306 if (dsn_ret == dsn_ret_hdrs)
2307 { Ustrcpy(p, " RET=HDRS"); p += 9; }
2308 else if (dsn_ret == dsn_ret_full)
2309 { Ustrcpy(p, " RET=FULL"); p += 9; }
2313 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ENVID=%s", dsn_envid);
2318 /* If an authenticated_sender override has been specified for this transport
2319 instance, expand it. If the expansion is forced to fail, and there was already
2320 an authenticated_sender for this message, the original value will be used.
2321 Other expansion failures are serious. An empty result is ignored, but there is
2322 otherwise no check - this feature is expected to be used with LMTP and other
2323 cases where non-standard addresses (e.g. without domains) might be required. */
2325 if (smtp_mail_auth_str(p, sizeof(sx->buffer) - (p-sx->buffer), addrlist, sx->ob))
2333 build_rcptcmd_options(smtp_context * sx, const address_item * addr)
2335 uschar * p = sx->buffer;
2338 /* Add any DSN flags to the rcpt command */
2340 if (sx->peer_offered & PEER_OFFERED_DSN && !(addr->dsn_flags & rf_dsnlasthop))
2342 if (addr->dsn_flags & rf_dsnflags)
2347 Ustrcpy(p, " NOTIFY=");
2349 for (i = 0; i < nelem(rf_list); i++) if (addr->dsn_flags & rf_list[i])
2351 if (!first) *p++ = ',';
2353 Ustrcpy(p, rf_names[i]);
2358 if (addr->dsn_orcpt)
2360 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ORCPT=%s",
2371 0 good, rcpt results in addr->transport_return (PENDING_OK, DEFER, FAIL)
2372 -1 MAIL response error
2373 -2 any non-MAIL read i/o error
2374 -3 non-MAIL response timeout
2375 -4 internal error; channel still usable
2380 smtp_write_mail_and_rcpt_cmds(smtp_context * sx, int * yield)
2382 address_item * addr;
2386 if (build_mailcmd_options(sx, sx->first_addr) != OK)
2392 /* From here until we send the DATA command, we can make use of PIPELINING
2393 if the server host supports it. The code has to be able to check the responses
2394 at any point, for when the buffer fills up, so we write it totally generally.
2395 When PIPELINING is off, each command written reports that it has flushed the
2398 sx->pending_MAIL = TRUE; /* The block starts with MAIL */
2401 uschar * s = sx->from_addr;
2403 uschar * errstr = NULL;
2405 /* If we must downconvert, do the from-address here. Remember we had to
2406 for the to-addresses (done below), and also (ugly) for re-doing when building
2407 the delivery log line. */
2409 if ( sx->addrlist->prop.utf8_msg
2410 && (sx->addrlist->prop.utf8_downcvt || !(sx->peer_offered & PEER_OFFERED_UTF8))
2413 if (s = string_address_utf8_to_alabel(s, &errstr), errstr)
2415 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE);
2419 setflag(sx->addrlist, af_utf8_downcvt);
2423 rc = smtp_write_command(&sx->outblock, pipelining_active,
2424 "MAIL FROM:<%s>%s\r\n", s, sx->buffer);
2427 mail_command = string_copy(big_buffer); /* Save for later error message */
2431 case -1: /* Transmission error */
2434 case +1: /* Cmd was sent */
2435 if (!smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer), '2',
2436 sx->ob->command_timeout))
2438 if (errno == 0 && sx->buffer[0] == '4')
2440 errno = ERRNO_MAIL4XX;
2441 sx->addrlist->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
2445 sx->pending_MAIL = FALSE;
2448 /* otherwise zero: command queued for pipeline */
2451 /* Pass over all the relevant recipient addresses for this host, which are the
2452 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
2453 several before we have to read the responses for those seen so far. This
2454 checking is done by a subroutine because it also needs to be done at the end.
2455 Send only up to max_rcpt addresses at a time, leaving next_addr pointing to
2456 the next one if not all are sent.
2458 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
2459 last address because we want to abort if any recipients have any kind of
2460 problem, temporary or permanent. We know that all recipient addresses will have
2461 the PENDING_DEFER status, because only one attempt is ever made, and we know
2462 that max_rcpt will be large, so all addresses will be done at once.
2464 For verify we flush the pipeline after any (the only) rcpt address. */
2466 for (addr = sx->first_addr, address_count = 0;
2467 addr && address_count < sx->max_rcpt;
2468 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
2474 addr->dsn_aware = sx->peer_offered & PEER_OFFERED_DSN
2475 ? dsn_support_yes : dsn_support_no;
2478 no_flush = pipelining_active && !sx->verify && (!mua_wrapper || addr->next);
2480 build_rcptcmd_options(sx, addr);
2482 /* Now send the RCPT command, and process outstanding responses when
2483 necessary. After a timeout on RCPT, we just end the function, leaving the
2484 yield as OK, because this error can often mean that there is a problem with
2485 just one address, so we don't want to delay the host. */
2487 rcpt_addr = transport_rcpt_address(addr, sx->tblock->rcpt_include_affixes);
2490 if ( testflag(sx->addrlist, af_utf8_downcvt)
2491 && !(rcpt_addr = string_address_utf8_to_alabel(rcpt_addr, NULL))
2494 /*XXX could we use a per-address errstr here? Not fail the whole send? */
2495 errno = ERRNO_EXPANDFAIL;
2496 return -5; /*XXX too harsh? */
2500 count = smtp_write_command(&sx->outblock, no_flush, "RCPT TO:<%s>%s%s\r\n",
2501 rcpt_addr, sx->igquotstr, sx->buffer);
2503 if (count < 0) return -5;
2506 switch(sync_responses(sx, count, 0))
2508 case 3: sx->ok = TRUE; /* 2xx & 5xx => OK & progress made */
2509 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
2512 case 1: sx->ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2513 if (!sx->lmtp) /* can't tell about progress yet */
2514 sx->completed_addr = TRUE;
2515 case 0: /* No 2xx or 5xx, but no probs */
2518 case -1: return -3; /* Timeout on RCPT */
2519 case -2: return -2; /* non-MAIL read i/o error */
2520 default: return -1; /* any MAIL error */
2522 sx->pending_MAIL = FALSE; /* Dealt with MAIL */
2524 } /* Loop for next address */
2526 sx->next_addr = addr;
2532 /*****************************************************
2533 * Proxy TLS connection for another transport process *
2534 ******************************************************/
2536 Use the given buffer as a staging area, and select on both the given fd
2537 and the TLS'd client-fd for data to read (per the coding in ip_recv() and
2538 fd_ready() this is legitimate). Do blocking full-size writes, and reads
2542 buf space to use for buffering
2543 bufsiz size of buffer
2544 proxy_fd comms to proxied process
2545 timeout per-read timeout, seconds
2549 smtp_proxy_tls(uschar * buf, size_t bsize, int proxy_fd, int timeout)
2552 int max_fd = MAX(proxy_fd, tls_out.active) + 1;
2553 int rc, i, fd_bits, nbytes;
2555 set_process_info("proxying TLS connection for continued transport");
2557 FD_SET(tls_out.active, &fds);
2558 FD_SET(proxy_fd, &fds);
2560 for (fd_bits = 3; fd_bits; )
2562 time_t time_left = timeout;
2563 time_t time_start = time(NULL);
2568 struct timeval tv = { time_left, 0 };
2570 rc = select(max_fd, (SELECT_ARG2_TYPE *)&fds, NULL, NULL, &tv);
2572 if (rc < 0 && errno == EINTR)
2573 if ((time_left -= time(NULL) - time_start) > 0) continue;
2577 DEBUG(D_transport) if (rc == 0) debug_printf("%s: timed out\n", __FUNCTION__);
2581 while (rc < 0 || !(FD_ISSET(tls_out.active, &fds) || FD_ISSET(proxy_fd, &fds)));
2583 /* handle inbound data */
2584 if (FD_ISSET(tls_out.active, &fds))
2585 if ((rc = tls_read(FALSE, buf, bsize)) <= 0)
2588 FD_CLR(tls_out.active, &fds);
2589 shutdown(proxy_fd, SHUT_WR);
2593 for (nbytes = 0; rc - nbytes > 0; nbytes += i)
2594 if ((i = write(proxy_fd, buf + nbytes, rc - nbytes)) < 0) return;
2596 else if (fd_bits & 1)
2597 FD_SET(tls_out.active, &fds);
2599 /* handle outbound data */
2600 if (FD_ISSET(proxy_fd, &fds))
2601 if ((rc = read(proxy_fd, buf, bsize)) <= 0)
2604 FD_CLR(proxy_fd, &fds);
2605 shutdown(tls_out.active, SHUT_WR);
2609 for (nbytes = 0; rc - nbytes > 0; nbytes += i)
2610 if ((i = tls_write(FALSE, buf + nbytes, rc - nbytes)) < 0) return;
2612 else if (fd_bits & 2)
2613 FD_SET(proxy_fd, &fds);
2619 /*************************************************
2620 * Deliver address list to given host *
2621 *************************************************/
2623 /* If continue_hostname is not null, we get here only when continuing to
2624 deliver down an existing channel. The channel was passed as the standard
2625 input. TLS is never active on a passed channel; the previous process always
2626 closes it down before passing the connection on.
2628 Otherwise, we have to make a connection to the remote host, and do the
2629 initial protocol exchange.
2631 When running as an MUA wrapper, if the sender or any recipient is rejected,
2632 temporarily or permanently, we force failure for all recipients.
2635 addrlist chain of potential addresses to deliver; only those whose
2636 transport_return field is set to PENDING_DEFER are currently
2637 being processed; others should be skipped - they have either
2638 been delivered to an earlier host or IP address, or been
2639 failed by one of them.
2640 host host to deliver to
2641 host_af AF_INET or AF_INET6
2642 port default TCP/IP port to use, in host byte order
2643 interface interface to bind to, or NULL
2644 tblock transport instance block
2645 message_defer set TRUE if yield is OK, but all addresses were deferred
2646 because of a non-recipient, non-host failure, that is, a
2647 4xx response to MAIL FROM, DATA, or ".". This is a defer
2648 that is specific to the message.
2649 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
2650 a second attempt after TLS initialization fails
2652 Returns: OK - the connection was made and the delivery attempted;
2653 the result for each address is in its data block.
2654 DEFER - the connection could not be made, or something failed
2655 while setting up the SMTP session, or there was a
2656 non-message-specific error, such as a timeout.
2657 ERROR - a filter command is specified for this transport,
2658 and there was a problem setting it up; OR helo_data
2659 or add_headers or authenticated_sender is specified
2660 for this transport, and the string failed to expand
2664 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
2665 uschar *interface, transport_instance *tblock,
2666 BOOL *message_defer, BOOL suppress_tls)
2672 time_t start_delivery_time = time(NULL);
2674 BOOL pass_message = FALSE;
2675 uschar *message = NULL;
2676 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
2681 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
2682 *message_defer = FALSE;
2684 sx.addrlist = addrlist;
2686 sx.host_af = host_af,
2688 sx.interface = interface;
2689 sx.helo_data = NULL;
2693 /* Get the channel set up ready for a message (MAIL FROM being the next
2694 SMTP command to send */
2696 if ((rc = smtp_setup_conn(&sx, suppress_tls)) != OK)
2699 /* If there is a filter command specified for this transport, we can now
2700 set it up. This cannot be done until the identify of the host is known. */
2702 if (tblock->filter_command)
2706 sprintf(CS fbuf, "%.50s transport", tblock->name);
2707 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
2708 TRUE, DEFER, addrlist, fbuf, NULL);
2709 transport_filter_timeout = tblock->filter_timeout;
2711 /* On failure, copy the error to all addresses, abandon the SMTP call, and
2716 set_errno_nohost(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
2722 if ( transport_filter_argv
2723 && *transport_filter_argv
2724 && **transport_filter_argv
2725 && sx.peer_offered & PEER_OFFERED_CHUNKING
2728 sx.peer_offered &= ~PEER_OFFERED_CHUNKING;
2729 DEBUG(D_transport) debug_printf("CHUNKING not usable due to transport filter\n");
2734 /* For messages that have more than the maximum number of envelope recipients,
2735 we want to send several transactions down the same SMTP connection. (See
2736 comments in deliver.c as to how this reconciles, heuristically, with
2737 remote_max_parallel.) This optimization was added to Exim after the following
2738 code was already working. The simplest way to put it in without disturbing the
2739 code was to use a goto to jump back to this point when there is another
2740 transaction to handle. */
2743 sx.from_addr = return_path;
2744 sx.first_addr = sx.sync_addr = addrlist;
2746 sx.send_rset = TRUE;
2747 sx.completed_addr = FALSE;
2750 /* If we are a continued-connection-after-verify the MAIL and RCPT
2751 commands were already sent; do not re-send but do mark the addrs as
2752 having been accepted up to RCPT stage. A traditional cont-conn
2753 always has a sequence number greater than one. */
2755 if (continue_hostname && continue_sequence == 1)
2757 address_item * addr;
2759 sx.peer_offered = smtp_peer_options;
2761 sx.next_addr = NULL;
2763 for (addr = addrlist; addr; addr = addr->next)
2764 addr->transport_return = PENDING_OK;
2768 /* Initiate a message transfer. */
2770 switch(smtp_write_mail_and_rcpt_cmds(&sx, &yield))
2773 case -1: case -2: goto RESPONSE_FAILED;
2774 case -3: goto END_OFF;
2775 case -4: goto SEND_QUIT;
2776 default: goto SEND_FAILED;
2779 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
2780 permanently or temporarily. We should have flushed and synced after the last
2785 address_item *badaddr;
2786 for (badaddr = sx.first_addr; badaddr; badaddr = badaddr->next)
2787 if (badaddr->transport_return != PENDING_OK)
2789 /*XXX could we find a better errno than 0 here? */
2790 set_errno_nohost(addrlist, 0, badaddr->message, FAIL,
2791 testflag(badaddr, af_pass_message));
2798 /* If ok is TRUE, we know we have got at least one good recipient, and must now
2799 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
2800 have a good recipient buffered up if we are pipelining. We don't want to waste
2801 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
2802 are pipelining. The responses are all handled by sync_responses().
2803 If using CHUNKING, do not send a BDAT until we know how big a chunk we want
2806 if ( !(sx.peer_offered & PEER_OFFERED_CHUNKING)
2807 && (sx.ok || (pipelining_active && !mua_wrapper)))
2809 int count = smtp_write_command(&sx.outblock, FALSE, "DATA\r\n");
2811 if (count < 0) goto SEND_FAILED;
2812 switch(sync_responses(&sx, count, sx.ok ? +1 : -1))
2814 case 3: sx.ok = TRUE; /* 2xx & 5xx => OK & progress made */
2815 case 2: sx.completed_addr = TRUE; /* 5xx (only) => progress made */
2818 case 1: sx.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2819 if (!sx.lmtp) sx.completed_addr = TRUE; /* can't tell about progress yet */
2820 case 0: break; /* No 2xx or 5xx, but no probs */
2822 case -1: goto END_OFF; /* Timeout on RCPT */
2823 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2825 pipelining_active = FALSE;
2826 data_command = string_copy(big_buffer); /* Save for later error message */
2829 /* If there were no good recipients (but otherwise there have been no
2830 problems), just set ok TRUE, since we have handled address-specific errors
2831 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
2832 for handling the SMTP dot-handling protocol, flagging to apply to headers as
2833 well as body. Set the appropriate timeout value to be used for each chunk.
2834 (Haven't been able to make it work using select() for writing yet.) */
2836 if (!(sx.peer_offered & PEER_OFFERED_CHUNKING) && !sx.ok)
2838 /* Save the first address of the next batch. */
2839 sx.first_addr = sx.next_addr;
2845 transport_ctx tctx = {
2848 US".", US"..", /* Escaping strings */
2849 topt_use_crlf | topt_escape_headers
2850 | (tblock->body_only ? topt_no_headers : 0)
2851 | (tblock->headers_only ? topt_no_body : 0)
2852 | (tblock->return_path_add ? topt_add_return_path : 0)
2853 | (tblock->delivery_date_add ? topt_add_delivery_date : 0)
2854 | (tblock->envelope_to_add ? topt_add_envelope_to : 0)
2857 /* If using CHUNKING we need a callback from the generic transport
2858 support to us, for the sending of BDAT smtp commands and the reaping
2859 of responses. The callback needs a whole bunch of state so set up
2860 a transport-context structure to be passed around. */
2862 if (sx.peer_offered & PEER_OFFERED_CHUNKING)
2864 tctx.check_string = tctx.escape_string = NULL;
2865 tctx.options |= topt_use_bdat;
2866 tctx.chunk_cb = smtp_chunk_cmd_callback;
2867 sx.pending_BDAT = FALSE;
2868 sx.good_RCPT = sx.ok;
2870 tctx.smtp_context = &sx;
2873 tctx.options |= topt_end_dot;
2875 /* Save the first address of the next batch. */
2876 sx.first_addr = sx.next_addr;
2878 /* Responses from CHUNKING commands go in buffer. Otherwise,
2879 there has not been a response. */
2883 sigalrm_seen = FALSE;
2884 transport_write_timeout = sx.ob->data_timeout;
2885 smtp_command = US"sending data block"; /* For error messages */
2886 DEBUG(D_transport|D_v)
2887 if (sx.peer_offered & PEER_OFFERED_CHUNKING)
2888 debug_printf(" will write message using CHUNKING\n");
2890 debug_printf(" SMTP>> writing message and terminating \".\"\n");
2891 transport_count = 0;
2893 #ifndef DISABLE_DKIM
2894 sx.ok = dkim_transport_write_message(sx.inblock.sock, &tctx, &sx.ob->dkim,
2897 sx.ok = transport_write_message(sx.inblock.sock, &tctx, 0);
2900 /* transport_write_message() uses write() because it is called from other
2901 places to write to non-sockets. This means that under some OS (e.g. Solaris)
2902 it can exit with "Broken pipe" as its error. This really means that the
2903 socket got closed at the far end. */
2905 transport_write_timeout = 0; /* for subsequent transports */
2907 /* Failure can either be some kind of I/O disaster (including timeout),
2908 or the failure of a transport filter or the expansion of added headers.
2909 Or, when CHUNKING, it can be a protocol-detected failure. */
2912 if (message) goto SEND_FAILED;
2913 else goto RESPONSE_FAILED;
2915 /* We used to send the terminating "." explicitly here, but because of
2916 buffering effects at both ends of TCP/IP connections, you don't gain
2917 anything by keeping it separate, so it might as well go in the final
2918 data buffer for efficiency. This is now done by setting the topt_end_dot
2921 smtp_command = US"end of data";
2923 if (sx.peer_offered & PEER_OFFERED_CHUNKING && sx.cmd_count > 1)
2925 /* Reap any outstanding MAIL & RCPT commands, but not a DATA-go-ahead */
2926 switch(sync_responses(&sx, sx.cmd_count-1, 0))
2928 case 3: sx.ok = TRUE; /* 2xx & 5xx => OK & progress made */
2929 case 2: sx.completed_addr = TRUE; /* 5xx (only) => progress made */
2932 case 1: sx.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2933 if (!sx.lmtp) sx.completed_addr = TRUE; /* can't tell about progress yet */
2934 case 0: break; /* No 2xx or 5xx, but no probs */
2936 case -1: goto END_OFF; /* Timeout on RCPT */
2937 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2941 #ifndef DISABLE_PRDR
2942 /* For PRDR we optionally get a partial-responses warning
2943 * followed by the individual responses, before going on with
2944 * the overall response. If we don't get the warning then deal
2945 * with per non-PRDR. */
2948 sx.ok = smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer), '3',
2949 sx.ob->final_timeout);
2950 if (!sx.ok && errno == 0) switch(sx.buffer[0])
2952 case '2': sx.prdr_active = FALSE;
2955 case '4': errno = ERRNO_DATA4XX;
2956 addrlist->more_errno |=
2957 ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
2964 /* For non-PRDR SMTP, we now read a single response that applies to the
2965 whole message. If it is OK, then all the addresses have been delivered. */
2969 sx.ok = smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer), '2',
2970 sx.ob->final_timeout);
2971 if (!sx.ok && errno == 0 && sx.buffer[0] == '4')
2973 errno = ERRNO_DATA4XX;
2974 addrlist->more_errno |= ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
2978 /* For LMTP, we get back a response for every RCPT command that we sent;
2979 some may be accepted and some rejected. For those that get a response, their
2980 status is fixed; any that are accepted have been handed over, even if later
2981 responses crash - at least, that's how I read RFC 2033.
2983 If all went well, mark the recipient addresses as completed, record which
2984 host/IPaddress they were delivered to, and cut out RSET when sending another
2985 message down the same channel. Write the completed addresses to the journal
2986 now so that they are recorded in case there is a crash of hardware or
2987 software before the spool gets updated. Also record the final SMTP
2988 confirmation if needed (for SMTP only). */
2993 int delivery_time = (int)(time(NULL) - start_delivery_time);
2995 uschar *conf = NULL;
2997 sx.send_rset = FALSE;
2998 pipelining_active = FALSE;
3000 /* Set up confirmation if needed - applies only to SMTP */
3003 #ifdef DISABLE_EVENT
3004 LOGGING(smtp_confirmation) &&
3009 const uschar *s = string_printing(sx.buffer);
3010 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
3011 conf = (s == sx.buffer)? (uschar *)string_copy(s) : US s;
3014 /* Process all transported addresses - for LMTP or PRDR, read a status for
3017 for (addr = addrlist; addr != sx.first_addr; addr = addr->next)
3019 if (addr->transport_return != PENDING_OK) continue;
3021 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
3022 remaining addresses. Otherwise, it's a return code for just the one
3023 address. For temporary errors, add a retry item for the address so that
3024 it doesn't get tried again too soon. */
3026 #ifndef DISABLE_PRDR
3027 if (sx.lmtp || sx.prdr_active)
3032 if (!smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer), '2',
3033 sx.ob->final_timeout))
3035 if (errno != 0 || sx.buffer[0] == 0) goto RESPONSE_FAILED;
3036 addr->message = string_sprintf(
3037 #ifndef DISABLE_PRDR
3038 "%s error after %s: %s", sx.prdr_active ? "PRDR":"LMTP",
3040 "LMTP error after %s: %s",
3042 data_command, string_printing(sx.buffer));
3043 setflag(addr, af_pass_message); /* Allow message to go to user */
3044 if (sx.buffer[0] == '5')
3045 addr->transport_return = FAIL;
3048 errno = ERRNO_DATA4XX;
3049 addr->more_errno |= ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
3050 addr->transport_return = DEFER;
3051 #ifndef DISABLE_PRDR
3052 if (!sx.prdr_active)
3054 retry_add_item(addr, addr->address_retry_key, 0);
3058 sx.completed_addr = TRUE; /* NOW we can set this flag */
3059 if (LOGGING(smtp_confirmation))
3061 const uschar *s = string_printing(sx.buffer);
3062 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
3063 conf = (s == sx.buffer) ? US string_copy(s) : US s;
3067 /* SMTP, or success return from LMTP for this address. Pass back the
3068 actual host that was used. */
3070 addr->transport_return = OK;
3071 addr->more_errno = delivery_time;
3072 addr->host_used = host;
3073 addr->special_action = flag;
3074 addr->message = conf;
3075 #ifndef DISABLE_PRDR
3076 if (sx.prdr_active) addr->flags |= af_prdr_used;
3078 if (sx.peer_offered & PEER_OFFERED_CHUNKING) addr->flags |= af_chunking_used;
3081 #ifndef DISABLE_PRDR
3082 if (!sx.prdr_active)
3085 /* Update the journal. For homonymic addresses, use the base address plus
3086 the transport name. See lots of comments in deliver.c about the reasons
3087 for the complications when homonyms are involved. Just carry on after
3088 write error, as it may prove possible to update the spool file later. */
3090 if (testflag(addr, af_homonym))
3091 sprintf(CS sx.buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
3093 sprintf(CS sx.buffer, "%.500s\n", addr->unique);
3095 DEBUG(D_deliver) debug_printf("S:journalling %s\n", sx.buffer);
3096 len = Ustrlen(CS sx.buffer);
3097 if (write(journal_fd, sx.buffer, len) != len)
3098 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
3099 "%s: %s", sx.buffer, strerror(errno));
3103 #ifndef DISABLE_PRDR
3106 /* PRDR - get the final, overall response. For any non-success
3107 upgrade all the address statuses. */
3108 sx.ok = smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer), '2',
3109 sx.ob->final_timeout);
3112 if(errno == 0 && sx.buffer[0] == '4')
3114 errno = ERRNO_DATA4XX;
3115 addrlist->more_errno |= ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
3117 for (addr = addrlist; addr != sx.first_addr; addr = addr->next)
3118 if (sx.buffer[0] == '5' || addr->transport_return == OK)
3119 addr->transport_return = PENDING_OK; /* allow set_errno action */
3120 goto RESPONSE_FAILED;
3123 /* Update the journal, or setup retry. */
3124 for (addr = addrlist; addr != sx.first_addr; addr = addr->next)
3125 if (addr->transport_return == OK)
3127 if (testflag(addr, af_homonym))
3128 sprintf(CS sx.buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
3130 sprintf(CS sx.buffer, "%.500s\n", addr->unique);
3132 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s\n", sx.buffer);
3133 len = Ustrlen(CS sx.buffer);
3134 if (write(journal_fd, sx.buffer, len) != len)
3135 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
3136 "%s: %s", sx.buffer, strerror(errno));
3138 else if (addr->transport_return == DEFER)
3139 retry_add_item(addr, addr->address_retry_key, -2);
3143 /* Ensure the journal file is pushed out to disk. */
3145 if (EXIMfsync(journal_fd) < 0)
3146 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
3152 /* Handle general (not specific to one address) failures here. The value of ok
3153 is used to skip over this code on the falling through case. A timeout causes a
3154 deferral. Other errors may defer or fail according to the response code, and
3155 may set up a special errno value, e.g. after connection chopped, which is
3156 assumed if errno == 0 and there is no text in the buffer. If control reaches
3157 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
3158 the problem is not related to this specific message. */
3163 uschar * set_message;
3169 sx.send_quit = check_response(host, &save_errno, addrlist->more_errno,
3170 sx.buffer, &code, &message, &pass_message);
3178 message = string_sprintf("send() to %s [%s] failed: %s",
3179 host->name, host->address, message ? message : US strerror(save_errno));
3180 sx.send_quit = FALSE;
3188 sx.ok = FALSE; /* For when reached by GOTO */
3189 set_message = message;
3191 /* We want to handle timeouts after MAIL or "." and loss of connection after
3192 "." specially. They can indicate a problem with the sender address or with
3193 the contents of the message rather than a real error on the connection. These
3194 cases are treated in the same way as a 4xx response. This next bit of code
3195 does the classification. */
3202 message_error = TRUE;
3206 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
3207 Ustrncmp(smtp_command,"end ",4) == 0;
3210 case ERRNO_SMTPCLOSED:
3211 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
3215 message_error = FALSE;
3219 /* Handle the cases that are treated as message errors. These are:
3221 (a) negative response or timeout after MAIL
3222 (b) negative response after DATA
3223 (c) negative response or timeout or dropped connection after "."
3224 (d) utf8 support required and not offered
3226 It won't be a negative response or timeout after RCPT, as that is dealt
3227 with separately above. The action in all cases is to set an appropriate
3228 error code for all the addresses, but to leave yield set to OK because the
3229 host itself has not failed. Of course, it might in practice have failed
3230 when we've had a timeout, but if so, we'll discover that at the next
3231 delivery attempt. For a temporary error, set the message_defer flag, and
3232 write to the logs for information if this is not the last host. The error
3233 for the last host will be logged as part of the address's log line. */
3237 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
3239 /* If there's an errno, the message contains just the identity of
3244 else /* Anything other than 5 is treated as temporary */
3248 message = US string_sprintf("%s: %s", message, strerror(save_errno));
3249 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
3250 msglog_line(host, message);
3251 *message_defer = TRUE;
3255 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
3256 ".", or some other transportation error. We defer all addresses and yield
3257 DEFER, except for the case of failed add_headers expansion, or a transport
3258 filter failure, when the yield should be ERROR, to stop it trying other
3264 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
3265 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
3269 set_errno(addrlist, save_errno, set_message, set_rc, pass_message, host
3270 #ifdef EXPERIMENTAL_DSN_INFO
3271 , sx.smtp_greeting, sx.helo_response
3277 /* If all has gone well, send_quit will be set TRUE, implying we can end the
3278 SMTP session tidily. However, if there were too many addresses to send in one
3279 message (indicated by first_addr being non-NULL) we want to carry on with the
3280 rest of them. Also, it is desirable to send more than one message down the SMTP
3281 connection if there are several waiting, provided we haven't already sent so
3282 many as to hit the configured limit. The function transport_check_waiting looks
3283 for a waiting message and returns its id. Then transport_pass_socket tries to
3284 set up a continued delivery by passing the socket on to another process. The
3285 variable send_rset is FALSE if a message has just been successfully transfered.
3287 If we are already sending down a continued channel, there may be further
3288 addresses not yet delivered that are aimed at the same host, but which have not
3289 been passed in this run of the transport. In this case, continue_more will be
3290 true, and all we should do is send RSET if necessary, and return, leaving the
3293 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
3294 do not want to continue with other messages down the same channel, because that
3295 can lead to looping between two or more messages, all with the same,
3296 temporarily failing address(es). [The retry information isn't updated yet, so
3297 new processes keep on trying.] We probably also don't want to try more of this
3298 message's addresses either.
3300 If we have started a TLS session, we have to end it before passing the
3301 connection to a new process. However, not all servers can handle this (Exim
3302 can), so we do not pass such a connection on if the host matches
3303 hosts_nopass_tls. */
3306 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
3307 "yield=%d first_address is %sNULL\n", sx.ok, sx.send_quit,
3308 sx.send_rset, continue_more, yield, sx.first_addr ? "not " : "");
3310 if (sx.completed_addr && sx.ok && sx.send_quit)
3313 smtp_compare_t t_compare;
3315 t_compare.tblock = tblock;
3316 t_compare.current_sender_address = sender_address;
3318 if ( sx.first_addr != NULL
3322 ( tls_out.active < 0 && !continue_proxy_cipher
3323 || verify_check_given_host(&sx.ob->hosts_nopass_tls, host) != OK
3327 transport_check_waiting(tblock->name, host->name,
3328 tblock->connection_max_messages, new_message_id, &more,
3329 (oicf)smtp_are_same_identities, (void*)&t_compare)
3336 if (! (sx.ok = smtp_write_command(&sx.outblock, FALSE, "RSET\r\n") >= 0))
3338 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
3339 host->address, strerror(errno));
3340 sx.send_quit = FALSE;
3342 else if (! (sx.ok = smtp_read_response(&sx.inblock, sx.buffer,
3343 sizeof(sx.buffer), '2', sx.ob->command_timeout)))
3346 sx.send_quit = check_response(host, &errno, 0, sx.buffer, &code, &msg,
3350 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
3351 host->name, host->address, msg);
3355 /* Either RSET was not needed, or it succeeded */
3360 int socket_fd = sx.inblock.sock;
3363 if (sx.first_addr != NULL) /* More addresses still to be sent */
3364 { /* in this run of the transport */
3365 continue_sequence++; /* Causes * in logging */
3368 if (continue_more) return yield; /* More addresses for another run */
3370 /* Pass the connection on to a new Exim process. */
3372 if (tls_out.active >= 0)
3373 if (verify_check_given_host(&sx.ob->hosts_noproxy_tls, host) == OK)
3375 /* Pass the socket, for direct use, to a new Exim process. Before
3376 doing so, we must shut down TLS. Not all MTAs allow for the
3377 continuation of the SMTP session when TLS is shut down. We test for
3378 this by sending a new EHLO. If we don't get a good response, we don't
3379 attempt to pass the socket on. */
3381 tls_close(FALSE, TRUE);
3382 smtp_peer_options = smtp_peer_options_wrap;
3384 && smtp_write_command(&sx.outblock, FALSE,
3385 "EHLO %s\r\n", sx.helo_data) >= 0
3386 && smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer),
3387 '2', sx.ob->command_timeout);
3391 /* Set up a pipe for proxying TLS for the new transport process */
3393 smtp_peer_options |= PEER_OFFERED_TLS;
3394 if (sx.ok = (socketpair(AF_UNIX, SOCK_STREAM, 0, pfd) == 0))
3397 set_errno(sx.first_addr, errno, US"internal allocation problem",
3399 # ifdef EXPERIMENTAL_DSN_INFO
3400 , sx.smtp_greeting, sx.helo_response
3406 /* If the socket is successfully passed, we mustn't send QUIT (or
3407 indeed anything!) from here. */
3409 /*XXX DSN_INFO: assume likely to do new HELO; but for greet we'll want to
3410 propagate it from the initial
3412 if (sx.ok && transport_pass_socket(tblock->name, host->name,
3413 host->address, new_message_id, socket_fd))
3415 sx.send_quit = FALSE;
3417 /* If TLS is still active, we need to proxy it for the transport we
3418 just passed the baton to. Fork a child to to do it, and return to
3419 get logging done asap. Which way to place the work makes assumptions
3420 about post-fork prioritisation which may not hold on all platforms. */
3422 if (tls_out.active >= 0)
3425 if (pid > 0) /* parent */
3427 tls_close(FALSE, FALSE);
3428 (void)close(sx.inblock.sock);
3429 continue_transport = NULL;
3430 continue_hostname = NULL;
3433 else if (pid == 0) /* child */
3435 smtp_proxy_tls(sx.buffer, sizeof(sx.buffer), pfd[0], sx.ob->command_timeout);
3443 /* If RSET failed and there are addresses left, they get deferred. */
3445 set_errno(sx.first_addr, errno, msg, DEFER, FALSE, host
3446 #ifdef EXPERIMENTAL_DSN_INFO
3447 , sx.smtp_greeting, sx.helo_response
3453 /* End off tidily with QUIT unless the connection has died or the socket has
3454 been passed to another process. There has been discussion on the net about what
3455 to do after sending QUIT. The wording of the RFC suggests that it is necessary
3456 to wait for a response, but on the other hand, there isn't anything one can do
3457 with an error response, other than log it. Exim used to do that. However,
3458 further discussion suggested that it is positively advantageous not to wait for
3459 the response, but to close the session immediately. This is supposed to move
3460 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
3461 load from the server. (Hosts that are both servers and clients may not see much
3462 difference, of course.) Further discussion indicated that this was safe to do
3463 on Unix systems which have decent implementations of TCP/IP that leave the
3464 connection around for a while (TIME_WAIT) after the application has gone away.
3465 This enables the response sent by the server to be properly ACKed rather than
3466 timed out, as can happen on broken TCP/IP implementations on other OS.
3468 This change is being made on 31-Jul-98. After over a year of trouble-free
3469 operation, the old commented-out code was removed on 17-Sep-99. */
3472 if (sx.send_quit) (void)smtp_write_command(&sx.outblock, FALSE, "QUIT\r\n");
3477 tls_close(FALSE, TRUE);
3480 /* Close the socket, and return the appropriate value, first setting
3481 works because the NULL setting is passed back to the calling process, and
3482 remote_max_parallel is forced to 1 when delivering over an existing connection,
3484 If all went well and continue_more is set, we shouldn't actually get here if
3485 there are further addresses, as the return above will be taken. However,
3486 writing RSET might have failed, or there may be other addresses whose hosts are
3487 specified in the transports, and therefore not visible at top level, in which
3488 case continue_more won't get set. */
3490 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
3493 shutdown(sx.outblock.sock, SHUT_WR);
3494 if (fcntl(sx.inblock.sock, F_SETFL, O_NONBLOCK) == 0)
3495 for (rc = 16; read(sx.inblock.sock, sx.inbuffer, sizeof(sx.inbuffer)) > 0 && rc > 0;)
3496 rc--; /* drain socket */
3498 (void)close(sx.inblock.sock);
3500 #ifndef DISABLE_EVENT
3501 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
3504 continue_transport = NULL;
3505 continue_hostname = NULL;
3512 /*************************************************
3513 * Closedown entry point *
3514 *************************************************/
3516 /* This function is called when exim is passed an open smtp channel
3517 from another incarnation, but the message which it has been asked
3518 to deliver no longer exists. The channel is on stdin.
3520 We might do fancy things like looking for another message to send down
3521 the channel, but if the one we sought has gone, it has probably been
3522 delivered by some other process that itself will seek further messages,
3523 so just close down our connection.
3525 Argument: pointer to the transport instance block
3530 smtp_transport_closedown(transport_instance *tblock)
3532 smtp_transport_options_block *ob =
3533 (smtp_transport_options_block *)tblock->options_block;
3534 smtp_inblock inblock;
3535 smtp_outblock outblock;
3537 uschar inbuffer[4096];
3538 uschar outbuffer[16];
3540 inblock.sock = fileno(stdin);
3541 inblock.buffer = inbuffer;
3542 inblock.buffersize = sizeof(inbuffer);
3543 inblock.ptr = inbuffer;
3544 inblock.ptrend = inbuffer;
3546 outblock.sock = inblock.sock;
3547 outblock.buffersize = sizeof(outbuffer);
3548 outblock.buffer = outbuffer;
3549 outblock.ptr = outbuffer;
3550 outblock.cmd_count = 0;
3551 outblock.authenticating = FALSE;
3553 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
3554 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
3555 ob->command_timeout);
3556 (void)close(inblock.sock);
3561 /*************************************************
3562 * Prepare addresses for delivery *
3563 *************************************************/
3565 /* This function is called to flush out error settings from previous delivery
3566 attempts to other hosts. It also records whether we got here via an MX record
3567 or not in the more_errno field of the address. We are interested only in
3568 addresses that are still marked DEFER - others may have got delivered to a
3569 previously considered IP address. Set their status to PENDING_DEFER to indicate
3570 which ones are relevant this time.
3573 addrlist the list of addresses
3574 host the host we are delivering to
3576 Returns: the first address for this delivery
3579 static address_item *
3580 prepare_addresses(address_item *addrlist, host_item *host)
3582 address_item *first_addr = NULL;
3584 for (addr = addrlist; addr; addr = addr->next)
3585 if (addr->transport_return == DEFER)
3587 if (!first_addr) first_addr = addr;
3588 addr->transport_return = PENDING_DEFER;
3589 addr->basic_errno = 0;
3590 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
3591 addr->message = NULL;
3593 addr->cipher = NULL;
3594 addr->ourcert = NULL;
3595 addr->peercert = NULL;
3596 addr->peerdn = NULL;
3597 addr->ocsp = OCSP_NOT_REQ;
3599 #ifdef EXPERIMENTAL_DSN_INFO
3600 addr->smtp_greeting = NULL;
3601 addr->helo_response = NULL;
3609 /*************************************************
3610 * Main entry point *
3611 *************************************************/
3613 /* See local README for interface details. As this is a remote transport, it is
3614 given a chain of addresses to be delivered in one connection, if possible. It
3615 always returns TRUE, indicating that each address has its own independent
3616 status set, except if there is a setting up problem, in which case it returns
3620 smtp_transport_entry(
3621 transport_instance *tblock, /* data for this instantiation */
3622 address_item *addrlist) /* addresses we are working on */
3626 int hosts_defer = 0;
3628 int hosts_looked_up = 0;
3629 int hosts_retry = 0;
3630 int hosts_serial = 0;
3631 int hosts_total = 0;
3632 int total_hosts_tried = 0;
3634 BOOL expired = TRUE;
3635 uschar *expanded_hosts = NULL;
3637 uschar *tid = string_sprintf("%s transport", tblock->name);
3638 smtp_transport_options_block *ob =
3639 (smtp_transport_options_block *)(tblock->options_block);
3640 host_item *hostlist = addrlist->host_list;
3641 host_item *host = NULL;
3645 debug_printf("%s transport entered\n", tblock->name);
3646 for (addr = addrlist; addr; addr = addr->next)
3647 debug_printf(" %s\n", addr->address);
3650 debug_printf("hostlist:\n");
3651 for (host = hostlist; host; host = host->next)
3652 debug_printf(" %s:%d\n", host->name, host->port);
3654 if (continue_hostname)
3655 debug_printf("already connected to %s [%s] (on fd %d)\n",
3656 continue_hostname, continue_host_address,
3657 cutthrough.fd >= 0 ? cutthrough.fd : 0);
3660 /* Set the flag requesting that these hosts be added to the waiting
3661 database if the delivery fails temporarily or if we are running with
3662 queue_smtp or a 2-stage queue run. This gets unset for certain
3663 kinds of error, typically those that are specific to the message. */
3665 update_waiting = TRUE;
3667 /* If a host list is not defined for the addresses - they must all have the
3668 same one in order to be passed to a single transport - or if the transport has
3669 a host list with hosts_override set, use the host list supplied with the
3670 transport. It is an error for this not to exist. */
3672 if (!hostlist || (ob->hosts_override && ob->hosts))
3676 addrlist->message = string_sprintf("%s transport called with no hosts set",
3678 addrlist->transport_return = PANIC;
3679 return FALSE; /* Only top address has status */
3682 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
3685 /* If the transport's host list contains no '$' characters, and we are not
3686 randomizing, it is fixed and therefore a chain of hosts can be built once
3687 and for all, and remembered for subsequent use by other calls to this
3688 transport. If, on the other hand, the host list does contain '$', or we are
3689 randomizing its order, we have to rebuild it each time. In the fixed case,
3690 as the hosts string will never be used again, it doesn't matter that we
3691 replace all the : characters with zeros. */
3695 uschar *s = ob->hosts;
3697 if (Ustrchr(s, '$') != NULL)
3699 if (!(expanded_hosts = expand_string(s)))
3701 addrlist->message = string_sprintf("failed to expand list of hosts "
3702 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
3703 addrlist->transport_return = search_find_defer ? DEFER : PANIC;
3704 return FALSE; /* Only top address has status */
3706 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
3707 "\"%s\"\n", s, expanded_hosts);
3711 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
3713 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
3715 /* Check that the expansion yielded something useful. */
3719 string_sprintf("%s transport has empty hosts setting", tblock->name);
3720 addrlist->transport_return = PANIC;
3721 return FALSE; /* Only top address has status */
3724 /* If there was no expansion of hosts, save the host list for
3727 if (!expanded_hosts) ob->hostlist = hostlist;
3730 /* This is not the first time this transport has been run in this delivery;
3731 the host list was built previously. */
3734 hostlist = ob->hostlist;
3737 /* The host list was supplied with the address. If hosts_randomize is set, we
3738 must sort it into a random order if it did not come from MX records and has not
3739 already been randomized (but don't bother if continuing down an existing
3742 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continue_hostname)
3744 host_item *newlist = NULL;
3747 host_item *h = hostlist;
3748 hostlist = hostlist->next;
3750 h->sort_key = random_number(100);
3757 else if (h->sort_key < newlist->sort_key)
3764 host_item *hh = newlist;
3767 if (h->sort_key < hh->next->sort_key) break;
3775 hostlist = addrlist->host_list = newlist;
3778 /* Sort out the default port. */
3780 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
3782 /* For each host-plus-IP-address on the list:
3784 . If this is a continued delivery and the host isn't the one with the
3785 current connection, skip.
3787 . If the status is unusable (i.e. previously failed or retry checked), skip.
3789 . If no IP address set, get the address, either by turning the name into
3790 an address, calling gethostbyname if gethostbyname is on, or by calling
3791 the DNS. The DNS may yield multiple addresses, in which case insert the
3792 extra ones into the list.
3794 . Get the retry data if not previously obtained for this address and set the
3795 field which remembers the state of this address. Skip if the retry time is
3796 not reached. If not, remember whether retry data was found. The retry string
3797 contains both the name and the IP address.
3799 . Scan the list of addresses and mark those whose status is DEFER as
3800 PENDING_DEFER. These are the only ones that will be processed in this cycle
3803 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
3804 Some addresses may be successfully delivered, others may fail, and yet
3805 others may get temporary errors and so get marked DEFER.
3807 . The return from the delivery attempt is OK if a connection was made and a
3808 valid SMTP dialogue was completed. Otherwise it is DEFER.
3810 . If OK, add a "remove" retry item for this host/IPaddress, if any.
3812 . If fail to connect, or other defer state, add a retry item.
3814 . If there are any addresses whose status is still DEFER, carry on to the
3815 next host/IPaddress, unless we have tried the number of hosts given
3816 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
3817 there is some fancy logic for hosts_max_try that means its limit can be
3818 overstepped in some circumstances.
3820 If we get to the end of the list, all hosts have deferred at least one address,
3821 or not reached their retry times. If delay_after_cutoff is unset, it requests a
3822 delivery attempt to those hosts whose last try was before the arrival time of
3823 the current message. To cope with this, we have to go round the loop a second
3824 time. After that, set the status and error data for any addresses that haven't
3825 had it set already. */
3827 for (cutoff_retry = 0;
3828 expired && cutoff_retry < (ob->delay_after_cutoff ? 1 : 2);
3831 host_item *nexthost = NULL;
3832 int unexpired_hosts_tried = 0;
3834 for (host = hostlist;
3836 && unexpired_hosts_tried < ob->hosts_max_try
3837 && total_hosts_tried < ob->hosts_max_try_hardlimit;
3843 BOOL host_is_expired = FALSE;
3844 BOOL message_defer = FALSE;
3845 BOOL some_deferred = FALSE;
3846 address_item *first_addr = NULL;
3847 uschar *interface = NULL;
3848 uschar *retry_host_key = NULL;
3849 uschar *retry_message_key = NULL;
3850 uschar *serialize_key = NULL;
3852 /* Default next host is next host. :-) But this can vary if the
3853 hosts_max_try limit is hit (see below). It may also be reset if a host
3854 address is looked up here (in case the host was multihomed). */
3856 nexthost = host->next;
3858 /* If the address hasn't yet been obtained from the host name, look it up
3859 now, unless the host is already marked as unusable. If it is marked as
3860 unusable, it means that the router was unable to find its IP address (in
3861 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
3862 the lookup failed last time. We don't get this far if *all* MX records
3863 point to non-existent hosts; that is treated as a hard error.
3865 We can just skip this host entirely. When the hosts came from the router,
3866 the address will timeout based on the other host(s); when the address is
3867 looked up below, there is an explicit retry record added.
3869 Note that we mustn't skip unusable hosts if the address is not unset; they
3870 may be needed as expired hosts on the 2nd time round the cutoff loop. */
3874 int new_port, flags;
3877 if (host->status >= hstatus_unusable)
3879 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
3884 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
3886 /* The host name is permitted to have an attached port. Find it, and
3887 strip it from the name. Just remember it for now. */
3889 new_port = host_item_get_port(host);
3891 /* Count hosts looked up */
3895 /* Find by name if so configured, or if it's an IP address. We don't
3896 just copy the IP address, because we need the test-for-local to happen. */
3898 flags = HOST_FIND_BY_A;
3899 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
3900 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
3902 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
3903 rc = host_find_byname(host, NULL, flags, NULL, TRUE);
3905 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
3906 &ob->dnssec, /* domains for request/require */
3909 /* Update the host (and any additional blocks, resulting from
3910 multihoming) with a host-specific port, if any. */
3912 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
3914 /* Failure to find the host at this time (usually DNS temporary failure)
3915 is really a kind of routing failure rather than a transport failure.
3916 Therefore we add a retry item of the routing kind, not to stop us trying
3917 to look this name up here again, but to ensure the address gets timed
3918 out if the failures go on long enough. A complete failure at this point
3919 commonly points to a configuration error, but the best action is still
3920 to carry on for the next host. */
3922 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_SECURITY || rc == HOST_FIND_FAILED)
3924 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
3926 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
3927 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
3928 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
3929 host->status = hstatus_unusable;
3931 for (addr = addrlist; addr; addr = addr->next)
3933 if (addr->transport_return != DEFER) continue;
3934 addr->basic_errno = ERRNO_UNKNOWNHOST;
3935 addr->message = string_sprintf(
3936 rc == HOST_FIND_SECURITY
3937 ? "lookup of IP address for %s was insecure"
3938 : "failed to lookup IP address for %s",
3944 /* If the host is actually the local host, we may have a problem, or
3945 there may be some cunning configuration going on. In the problem case,
3946 log things and give up. The default transport status is already DEFER. */
3948 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
3950 for (addr = addrlist; addr; addr = addr->next)
3952 addr->basic_errno = 0;
3953 addr->message = string_sprintf("%s transport found host %s to be "
3954 "local", tblock->name, host->name);
3958 } /* End of block for IP address lookup */
3960 /* If this is a continued delivery, we are interested only in the host
3961 which matches the name of the existing open channel. The check is put
3962 here after the local host lookup, in case the name gets expanded as a
3963 result of the lookup. Set expired FALSE, to save the outer loop executing
3966 if ( continue_hostname
3967 && ( Ustrcmp(continue_hostname, host->name) != 0
3968 || Ustrcmp(continue_host_address, host->address) != 0
3972 continue; /* With next host */
3975 /* Reset the default next host in case a multihomed host whose addresses
3976 are not looked up till just above added to the host list. */
3978 nexthost = host->next;
3980 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
3981 domain is in queue_smtp_domains, we don't actually want to attempt any
3982 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
3983 there is a lookup defer in queue_smtp_domains, proceed as if the domain
3984 were not in it. We don't want to hold up all SMTP deliveries! Except when
3985 doing a two-stage queue run, don't do this if forcing. */
3987 if ((!deliver_force || queue_2stage) && (queue_smtp ||
3988 match_isinlist(addrlist->domain,
3989 (const uschar **)&queue_smtp_domains, 0,
3990 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
3993 for (addr = addrlist; addr; addr = addr->next)
3994 if (addr->transport_return == DEFER)
3995 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
3996 continue; /* With next host */
3999 /* Count hosts being considered - purely for an intelligent comment
4000 if none are usable. */
4004 /* Set $host and $host address now in case they are needed for the
4005 interface expansion or the serialize_hosts check; they remain set if an
4006 actual delivery happens. */
4008 deliver_host = host->name;
4009 deliver_host_address = host->address;
4010 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
4011 : host->dnssec == DS_NO ? US"no"
4014 /* Set up a string for adding to the retry key if the port number is not
4015 the standard SMTP port. A host may have its own port setting that overrides
4018 pistring = string_sprintf(":%d", host->port == PORT_NONE
4019 ? port : host->port);
4020 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
4022 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
4023 string is set, even if constant (as different transports can have different
4024 constant settings), we must add it to the key that is used for retries,
4025 because connections to the same host from a different interface should be
4026 treated separately. */
4028 host_af = Ustrchr(host->address, ':') == NULL ? AF_INET : AF_INET6;
4029 if ((rs = ob->interface) && *rs)
4031 if (!smtp_get_interface(rs, host_af, addrlist, &interface, tid))
4033 pistring = string_sprintf("%s/%s", pistring, interface);
4036 /* The first time round the outer loop, check the status of the host by
4037 inspecting the retry data. The second time round, we are interested only
4038 in expired hosts that haven't been tried since this message arrived. */
4040 if (cutoff_retry == 0)
4043 /* Ensure the status of the address is set by checking retry data if
4044 necessary. There may be host-specific retry data (applicable to all
4045 messages) and also data for retries of a specific message at this host.
4046 If either of these retry records are actually read, the keys used are
4047 returned to save recomputing them later. */
4049 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
4050 US"retry_include_ip_address", ob->retry_include_ip_address,
4051 ob->expand_retry_include_ip_address, &incl_ip) != OK)
4052 continue; /* with next host */
4054 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
4055 incl_ip, &retry_host_key, &retry_message_key);
4057 DEBUG(D_transport) debug_printf("%s [%s]%s retry-status = %s\n", host->name,
4058 (host->address == NULL)? US"" : host->address, pistring,
4059 (host->status == hstatus_usable)? "usable" :
4060 (host->status == hstatus_unusable)? "unusable" :
4061 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
4063 /* Skip this address if not usable at this time, noting if it wasn't
4064 actually expired, both locally and in the address. */
4066 switch (host->status)
4068 case hstatus_unusable:
4070 setflag(addrlist, af_retry_skipped);
4073 case hstatus_unusable_expired:
4076 case hwhy_retry: hosts_retry++; break;
4077 case hwhy_failed: hosts_fail++; break;
4079 case hwhy_deferred: hosts_defer++; break;
4082 /* If there was a retry message key, implying that previously there
4083 was a message-specific defer, we don't want to update the list of
4084 messages waiting for these hosts. */
4086 if (retry_message_key) update_waiting = FALSE;
4087 continue; /* With the next host or IP address */
4091 /* Second time round the loop: if the address is set but expired, and
4092 the message is newer than the last try, let it through. */
4097 || host->status != hstatus_unusable_expired
4098 || host->last_try > received_time)
4100 DEBUG(D_transport) debug_printf("trying expired host %s [%s]%s\n",
4101 host->name, host->address, pistring);
4102 host_is_expired = TRUE;
4105 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
4106 it remains TRUE only if all hosts are expired and none are actually tried.
4111 /* If this host is listed as one to which access must be serialized,
4112 see if another Exim process has a connection to it, and if so, skip
4113 this host. If not, update the database to record our connection to it
4114 and remember this for later deletion. Do not do any of this if we are
4115 sending the message down a pre-existing connection. */
4117 if ( !continue_hostname
4118 && verify_check_given_host(&ob->serialize_hosts, host) == OK)
4120 serialize_key = string_sprintf("host-serialize-%s", host->name);
4121 if (!enq_start(serialize_key, 1))
4124 debug_printf("skipping host %s because another Exim process "
4125 "is connected to it\n", host->name);
4131 /* OK, we have an IP address that is not waiting for its retry time to
4132 arrive (it might be expired) OR (second time round the loop) we have an
4133 expired host that hasn't been tried since the message arrived. Have a go
4134 at delivering the message to it. First prepare the addresses by flushing
4135 out the result of previous attempts, and finding the first address that
4136 is still to be delivered. */
4138 first_addr = prepare_addresses(addrlist, host);
4140 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
4141 message_id, host->name, host->address, addrlist->address,
4142 addrlist->next ? ", ..." : "");
4144 set_process_info("delivering %s to %s [%s] (%s%s)",
4145 message_id, host->name, host->address, addrlist->address,
4146 addrlist->next ? ", ..." : "");
4148 /* This is not for real; don't do the delivery. If there are
4149 any remaining hosts, list them. */
4154 set_errno_nohost(addrlist, 0, NULL, OK, FALSE);
4155 for (addr = addrlist; addr; addr = addr->next)
4157 addr->host_used = host;
4158 addr->special_action = '*';
4159 addr->message = US"delivery bypassed by -N option";
4163 debug_printf("*** delivery by %s transport bypassed by -N option\n"
4164 "*** host and remaining hosts:\n", tblock->name);
4165 for (host2 = host; host2; host2 = host2->next)
4166 debug_printf(" %s [%s]\n", host2->name,
4167 host2->address ? host2->address : US"unset");
4172 /* This is for real. If the host is expired, we don't count it for
4173 hosts_max_retry. This ensures that all hosts must expire before an address
4174 is timed out, unless hosts_max_try_hardlimit (which protects against
4175 lunatic DNS configurations) is reached.
4177 If the host is not expired and we are about to hit the hosts_max_retry
4178 limit, check to see if there is a subsequent hosts with a different MX
4179 value. If so, make that the next host, and don't count this one. This is a
4180 heuristic to make sure that different MXs do get tried. With a normal kind
4181 of retry rule, they would get tried anyway when the earlier hosts were
4182 delayed, but if the domain has a "retry every time" type of rule - as is
4183 often used for the the very large ISPs, that won't happen. */
4188 /* Make a copy of the host if it is local to this invocation
4189 of the transport. */
4193 thost = store_get(sizeof(host_item));
4195 thost->name = string_copy(host->name);
4196 thost->address = string_copy(host->address);
4201 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
4205 debug_printf("hosts_max_try limit reached with this host\n");
4206 for (h = host; h; h = h->next) if (h->mx != host->mx)
4209 unexpired_hosts_tried--;
4210 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
4211 "and will be tried\n");
4216 /* Attempt the delivery. */
4218 total_hosts_tried++;
4219 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
4220 &message_defer, FALSE);
4223 OK => connection made, each address contains its result;
4224 message_defer is set for message-specific defers (when all
4225 recipients are marked defer)
4226 DEFER => there was a non-message-specific delivery problem;
4227 ERROR => there was a problem setting up the arguments for a filter,
4228 or there was a problem with expanding added headers
4231 /* If the result is not OK, there was a non-message-specific problem.
4232 If the result is DEFER, we need to write to the logs saying what happened
4233 for this particular host, except in the case of authentication and TLS
4234 failures, where the log has already been written. If all hosts defer a
4235 general message is written at the end. */
4237 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL
4238 && first_addr->basic_errno != ERRNO_TLSFAILURE)
4239 write_logs(first_addr, host);
4241 #ifndef DISABLE_EVENT
4243 deferred_event_raise(first_addr, host);
4246 /* If STARTTLS was accepted, but there was a failure in setting up the
4247 TLS session (usually a certificate screwup), and the host is not in
4248 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
4249 TLS forcibly turned off. We have to start from scratch with a new SMTP
4250 connection. That's why the retry is done from here, not from within
4251 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
4252 session, so the in-clear transmission after those errors, if permitted,
4253 happens inside smtp_deliver().] */
4257 && first_addr->basic_errno == ERRNO_TLSFAILURE
4258 && ob->tls_tempfail_tryclear
4259 && verify_check_given_host(&ob->hosts_require_tls, host) != OK
4262 log_write(0, LOG_MAIN,
4263 "%s: delivering unencrypted to H=%s [%s] (not in hosts_require_tls)",
4264 first_addr->message, host->name, host->address);
4265 first_addr = prepare_addresses(addrlist, host);
4266 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
4267 &message_defer, TRUE);
4268 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
4269 write_logs(first_addr, host);
4270 # ifndef DISABLE_EVENT
4272 deferred_event_raise(first_addr, host);
4275 #endif /*SUPPORT_TLS*/
4278 /* Delivery attempt finished */
4280 rs = rc == OK ? US"OK"
4281 : rc == DEFER ? US"DEFER"
4282 : rc == ERROR ? US"ERROR"
4285 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
4286 message_id, host->name, host->address, addrlist->address,
4287 addrlist->next ? " (& others)" : "", rs);
4289 /* Release serialization if set up */
4291 if (serialize_key) enq_end(serialize_key);
4293 /* If the result is DEFER, or if a host retry record is known to exist, we
4294 need to add an item to the retry chain for updating the retry database
4295 at the end of delivery. We only need to add the item to the top address,
4296 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
4297 for any other delivery attempts using the same address. (It is copied into
4298 the unusable tree at the outer level, so even if different address blocks
4299 contain the same address, it still won't get tried again.) */
4301 if (rc == DEFER || retry_host_key)
4303 int delete_flag = rc != DEFER ? rf_delete : 0;
4304 if (!retry_host_key)
4307 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
4308 US"retry_include_ip_address", ob->retry_include_ip_address,
4309 ob->expand_retry_include_ip_address, &incl_ip) != OK)
4310 incl_ip = TRUE; /* error; use most-specific retry record */
4312 retry_host_key = incl_ip
4313 ? string_sprintf("T:%S:%s%s", host->name, host->address, pistring)
4314 : string_sprintf("T:%S%s", host->name, pistring);
4317 /* If a delivery of another message over an existing SMTP connection
4318 yields DEFER, we do NOT set up retry data for the host. This covers the
4319 case when there are delays in routing the addresses in the second message
4320 that are so long that the server times out. This is alleviated by not
4321 routing addresses that previously had routing defers when handling an
4322 existing connection, but even so, this case may occur (e.g. if a
4323 previously happily routed address starts giving routing defers). If the
4324 host is genuinely down, another non-continued message delivery will
4325 notice it soon enough. */
4327 if (delete_flag != 0 || !continue_hostname)
4328 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
4330 /* We may have tried an expired host, if its retry time has come; ensure
4331 the status reflects the expiry for the benefit of any other addresses. */
4335 host->status = host_is_expired
4336 ? hstatus_unusable_expired : hstatus_unusable;
4337 host->why = hwhy_deferred;
4341 /* If message_defer is set (host was OK, but every recipient got deferred
4342 because of some message-specific problem), or if that had happened
4343 previously so that a message retry key exists, add an appropriate item
4344 to the retry chain. Note that if there was a message defer but now there is
4345 a host defer, the message defer record gets deleted. That seems perfectly
4346 reasonable. Also, stop the message from being remembered as waiting
4347 for specific hosts. */
4349 if (message_defer || retry_message_key)
4351 int delete_flag = message_defer ? 0 : rf_delete;
4352 if (!retry_message_key)
4355 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
4356 US"retry_include_ip_address", ob->retry_include_ip_address,
4357 ob->expand_retry_include_ip_address, &incl_ip) != OK)
4358 incl_ip = TRUE; /* error; use most-specific retry record */
4360 retry_message_key = incl_ip
4361 ? string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
4363 : string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
4365 retry_add_item(addrlist, retry_message_key,
4366 rf_message | rf_host | delete_flag);
4367 update_waiting = FALSE;
4370 /* Any return other than DEFER (that is, OK or ERROR) means that the
4371 addresses have got their final statuses filled in for this host. In the OK
4372 case, see if any of them are deferred. */
4375 for (addr = addrlist; addr; addr = addr->next)
4376 if (addr->transport_return == DEFER)
4378 some_deferred = TRUE;
4382 /* If no addresses deferred or the result was ERROR, return. We do this for
4383 ERROR because a failing filter set-up or add_headers expansion is likely to
4384 fail for any host we try. */
4386 if (rc == ERROR || (rc == OK && !some_deferred))
4388 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
4389 return TRUE; /* Each address has its status */
4392 /* If the result was DEFER or some individual addresses deferred, let
4393 the loop run to try other hosts with the deferred addresses, except for the
4394 case when we were trying to deliver down an existing channel and failed.
4395 Don't try any other hosts in this case. */
4397 if (continue_hostname) break;
4399 /* If the whole delivery, or some individual addresses, were deferred and
4400 there are more hosts that could be tried, do not count this host towards
4401 the hosts_max_try limit if the age of the message is greater than the
4402 maximum retry time for this host. This means we may try try all hosts,
4403 ignoring the limit, when messages have been around for some time. This is
4404 important because if we don't try all hosts, the address will never time
4405 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
4407 if ((rc == DEFER || some_deferred) && nexthost)
4410 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
4412 if (retry && retry->rules)
4414 retry_rule *last_rule;
4415 for (last_rule = retry->rules;
4417 last_rule = last_rule->next);
4418 timedout = time(NULL) - received_time > last_rule->timeout;
4420 else timedout = TRUE; /* No rule => timed out */
4424 unexpired_hosts_tried--;
4425 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
4426 "hosts_max_try (message older than host's retry time)\n");
4429 } /* End of loop for trying multiple hosts. */
4431 /* This is the end of the loop that repeats iff expired is TRUE and
4432 ob->delay_after_cutoff is FALSE. The second time round we will
4433 try those hosts that haven't been tried since the message arrived. */
4437 debug_printf("all IP addresses skipped or deferred at least one address\n");
4438 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
4439 debug_printf("retrying IP addresses not tried since message arrived\n");
4444 /* Get here if all IP addresses are skipped or defer at least one address. In
4445 MUA wrapper mode, this will happen only for connection or other non-message-
4446 specific failures. Force the delivery status for all addresses to FAIL. */
4450 for (addr = addrlist; addr; addr = addr->next)
4451 addr->transport_return = FAIL;
4455 /* In the normal, non-wrapper case, add a standard message to each deferred
4456 address if there hasn't been an error, that is, if it hasn't actually been
4457 tried this time. The variable "expired" will be FALSE if any deliveries were
4458 actually tried, or if there was at least one host that was not expired. That
4459 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
4460 a delivery has been tried, an error code will be set, and the failing of the
4461 message is handled by the retry code later.
4463 If queue_smtp is set, or this transport was called to send a subsequent message
4464 down an existing TCP/IP connection, and something caused the host not to be
4465 found, we end up here, but can detect these cases and handle them specially. */
4467 for (addr = addrlist; addr; addr = addr->next)
4469 /* If host is not NULL, it means that we stopped processing the host list
4470 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
4471 means we need to behave as if some hosts were skipped because their retry
4472 time had not come. Specifically, this prevents the address from timing out.
4473 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
4474 hosts were tried. */
4477 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
4480 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
4481 "hosts were tried\n");
4486 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
4487 setflag(addr, af_retry_skipped);
4490 if (queue_smtp) /* no deliveries attempted */
4492 addr->transport_return = DEFER;
4493 addr->basic_errno = 0;
4494 addr->message = US"SMTP delivery explicitly queued";
4497 else if ( addr->transport_return == DEFER
4498 && (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0)
4502 addr->basic_errno = ERRNO_HRETRY;
4503 if (continue_hostname)
4504 addr->message = US"no host found for existing SMTP connection";
4507 setflag(addr, af_pass_message); /* This is not a security risk */
4508 addr->message = string_sprintf(
4509 "all hosts%s have been failing for a long time %s",
4510 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"",
4511 ob->delay_after_cutoff
4512 ? US"(and retry time not reached)"
4513 : US"and were last tried after this message arrived");
4515 /* If we are already using fallback hosts, or there are no fallback hosts
4516 defined, convert the result to FAIL to cause a bounce. */
4518 if (addr->host_list == addr->fallback_hosts || !addr->fallback_hosts)
4519 addr->transport_return = FAIL;
4524 if (hosts_retry == hosts_total)
4525 s = "retry time not reached for any host%s";
4526 else if (hosts_fail == hosts_total)
4527 s = "all host address lookups%s failed permanently";
4528 else if (hosts_defer == hosts_total)
4529 s = "all host address lookups%s failed temporarily";
4530 else if (hosts_serial == hosts_total)
4531 s = "connection limit reached for all hosts%s";
4532 else if (hosts_fail+hosts_defer == hosts_total)
4533 s = "all host address lookups%s failed";
4535 s = "some host address lookups failed and retry time "
4536 "not reached for other hosts or connection limit reached%s";
4538 addr->message = string_sprintf(s,
4539 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"");
4544 /* Update the database which keeps information about which messages are waiting
4545 for which hosts to become available. For some message-specific errors, the
4546 update_waiting flag is turned off because we don't want follow-on deliveries in
4547 those cases. If this transport instance is explicitly limited to one message
4548 per connection then follow-on deliveries are not possible and there's no need
4549 to create/update the per-transport wait-<transport_name> database. */
4551 if (update_waiting && tblock->connection_max_messages != 1)
4552 transport_update_waiting(hostlist, tblock->name);
4556 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
4558 return TRUE; /* Each address has its status */
4563 /* End of transport/smtp.c */