1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2016 */
6 /* See the file NOTICE for conditions of use and distribution. */
12 #define PENDING_DEFER (PENDING + DEFER)
13 #define PENDING_OK (PENDING + OK)
16 /* Options specific to the smtp transport. This transport also supports LMTP
17 over TCP/IP. The options must be in alphabetic order (note that "_" comes
18 before the lower case letters). Some live in the transport_instance block so as
19 to be publicly visible; these are flagged with opt_public. */
21 optionlist smtp_transport_options[] = {
22 { "*expand_multi_domain", opt_stringptr | opt_hidden | opt_public,
23 (void *)offsetof(transport_instance, expand_multi_domain) },
24 { "*expand_retry_include_ip_address", opt_stringptr | opt_hidden,
25 (void *)(offsetof(smtp_transport_options_block, expand_retry_include_ip_address)) },
27 { "address_retry_include_sender", opt_bool,
28 (void *)offsetof(smtp_transport_options_block, address_retry_include_sender) },
29 { "allow_localhost", opt_bool,
30 (void *)offsetof(smtp_transport_options_block, allow_localhost) },
31 { "authenticated_sender", opt_stringptr,
32 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
33 { "authenticated_sender_force", opt_bool,
34 (void *)offsetof(smtp_transport_options_block, authenticated_sender_force) },
35 { "command_timeout", opt_time,
36 (void *)offsetof(smtp_transport_options_block, command_timeout) },
37 { "connect_timeout", opt_time,
38 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
39 { "connection_max_messages", opt_int | opt_public,
40 (void *)offsetof(transport_instance, connection_max_messages) },
41 { "data_timeout", opt_time,
42 (void *)offsetof(smtp_transport_options_block, data_timeout) },
43 { "delay_after_cutoff", opt_bool,
44 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
46 { "dkim_canon", opt_stringptr,
47 (void *)offsetof(smtp_transport_options_block, dkim.dkim_canon) },
48 { "dkim_domain", opt_stringptr,
49 (void *)offsetof(smtp_transport_options_block, dkim.dkim_domain) },
50 { "dkim_private_key", opt_stringptr,
51 (void *)offsetof(smtp_transport_options_block, dkim.dkim_private_key) },
52 { "dkim_selector", opt_stringptr,
53 (void *)offsetof(smtp_transport_options_block, dkim.dkim_selector) },
54 { "dkim_sign_headers", opt_stringptr,
55 (void *)offsetof(smtp_transport_options_block, dkim.dkim_sign_headers) },
56 { "dkim_strict", opt_stringptr,
57 (void *)offsetof(smtp_transport_options_block, dkim.dkim_strict) },
59 { "dns_qualify_single", opt_bool,
60 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
61 { "dns_search_parents", opt_bool,
62 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
63 { "dnssec_request_domains", opt_stringptr,
64 (void *)offsetof(smtp_transport_options_block, dnssec.request) },
65 { "dnssec_require_domains", opt_stringptr,
66 (void *)offsetof(smtp_transport_options_block, dnssec.require) },
67 { "dscp", opt_stringptr,
68 (void *)offsetof(smtp_transport_options_block, dscp) },
69 { "fallback_hosts", opt_stringptr,
70 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
71 { "final_timeout", opt_time,
72 (void *)offsetof(smtp_transport_options_block, final_timeout) },
73 { "gethostbyname", opt_bool,
74 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
75 { "helo_data", opt_stringptr,
76 (void *)offsetof(smtp_transport_options_block, helo_data) },
77 { "hosts", opt_stringptr,
78 (void *)offsetof(smtp_transport_options_block, hosts) },
79 { "hosts_avoid_esmtp", opt_stringptr,
80 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
81 { "hosts_avoid_pipelining", opt_stringptr,
82 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
84 { "hosts_avoid_tls", opt_stringptr,
85 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
87 { "hosts_max_try", opt_int,
88 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
89 { "hosts_max_try_hardlimit", opt_int,
90 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
92 { "hosts_nopass_tls", opt_stringptr,
93 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
95 { "hosts_override", opt_bool,
96 (void *)offsetof(smtp_transport_options_block, hosts_override) },
97 { "hosts_randomize", opt_bool,
98 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
99 #if defined(SUPPORT_TLS) && !defined(DISABLE_OCSP)
100 { "hosts_request_ocsp", opt_stringptr,
101 (void *)offsetof(smtp_transport_options_block, hosts_request_ocsp) },
103 { "hosts_require_auth", opt_stringptr,
104 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
106 # ifdef EXPERIMENTAL_DANE
107 { "hosts_require_dane", opt_stringptr,
108 (void *)offsetof(smtp_transport_options_block, hosts_require_dane) },
110 # ifndef DISABLE_OCSP
111 { "hosts_require_ocsp", opt_stringptr,
112 (void *)offsetof(smtp_transport_options_block, hosts_require_ocsp) },
114 { "hosts_require_tls", opt_stringptr,
115 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
117 { "hosts_try_auth", opt_stringptr,
118 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
119 { "hosts_try_chunking", opt_stringptr,
120 (void *)offsetof(smtp_transport_options_block, hosts_try_chunking) },
121 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
122 { "hosts_try_dane", opt_stringptr,
123 (void *)offsetof(smtp_transport_options_block, hosts_try_dane) },
126 { "hosts_try_prdr", opt_stringptr,
127 (void *)offsetof(smtp_transport_options_block, hosts_try_prdr) },
130 { "hosts_verify_avoid_tls", opt_stringptr,
131 (void *)offsetof(smtp_transport_options_block, hosts_verify_avoid_tls) },
133 { "interface", opt_stringptr,
134 (void *)offsetof(smtp_transport_options_block, interface) },
135 { "keepalive", opt_bool,
136 (void *)offsetof(smtp_transport_options_block, keepalive) },
137 { "lmtp_ignore_quota", opt_bool,
138 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
139 { "max_rcpt", opt_int | opt_public,
140 (void *)offsetof(transport_instance, max_addresses) },
141 { "multi_domain", opt_expand_bool | opt_public,
142 (void *)offsetof(transport_instance, multi_domain) },
143 { "port", opt_stringptr,
144 (void *)offsetof(smtp_transport_options_block, port) },
145 { "protocol", opt_stringptr,
146 (void *)offsetof(smtp_transport_options_block, protocol) },
147 { "retry_include_ip_address", opt_expand_bool,
148 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
149 { "serialize_hosts", opt_stringptr,
150 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
151 { "size_addition", opt_int,
152 (void *)offsetof(smtp_transport_options_block, size_addition) }
154 ,{ "socks_proxy", opt_stringptr,
155 (void *)offsetof(smtp_transport_options_block, socks_proxy) }
158 ,{ "tls_certificate", opt_stringptr,
159 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
160 { "tls_crl", opt_stringptr,
161 (void *)offsetof(smtp_transport_options_block, tls_crl) },
162 { "tls_dh_min_bits", opt_int,
163 (void *)offsetof(smtp_transport_options_block, tls_dh_min_bits) },
164 { "tls_privatekey", opt_stringptr,
165 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
166 { "tls_require_ciphers", opt_stringptr,
167 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
168 { "tls_sni", opt_stringptr,
169 (void *)offsetof(smtp_transport_options_block, tls_sni) },
170 { "tls_tempfail_tryclear", opt_bool,
171 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
172 { "tls_try_verify_hosts", opt_stringptr,
173 (void *)offsetof(smtp_transport_options_block, tls_try_verify_hosts) },
174 { "tls_verify_cert_hostnames", opt_stringptr,
175 (void *)offsetof(smtp_transport_options_block,tls_verify_cert_hostnames)},
176 { "tls_verify_certificates", opt_stringptr,
177 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) },
178 { "tls_verify_hosts", opt_stringptr,
179 (void *)offsetof(smtp_transport_options_block, tls_verify_hosts) }
183 /* Size of the options list. An extern variable has to be used so that its
184 address can appear in the tables drtables.c. */
186 int smtp_transport_options_count =
187 sizeof(smtp_transport_options)/sizeof(optionlist);
189 /* Default private options block for the smtp transport. */
191 smtp_transport_options_block smtp_transport_option_defaults = {
193 NULL, /* fallback_hosts */
195 NULL, /* fallback_hostlist */
196 NULL, /* authenticated_sender */
197 US"$primary_hostname", /* helo_data */
198 NULL, /* interface */
200 US"smtp", /* protocol */
202 NULL, /* serialize_hosts */
203 NULL, /* hosts_try_auth */
204 NULL, /* hosts_require_auth */
205 US"*", /* hosts_try_chunking */
206 #ifdef EXPERIMENTAL_DANE
207 NULL, /* hosts_try_dane */
208 NULL, /* hosts_require_dane */
211 US"*", /* hosts_try_prdr */
214 US"*", /* hosts_request_ocsp (except under DANE; tls_client_start()) */
215 NULL, /* hosts_require_ocsp */
217 NULL, /* hosts_require_tls */
218 NULL, /* hosts_avoid_tls */
219 NULL, /* hosts_verify_avoid_tls */
220 NULL, /* hosts_avoid_pipelining */
221 NULL, /* hosts_avoid_esmtp */
222 NULL, /* hosts_nopass_tls */
223 5*60, /* command_timeout */
224 5*60, /* connect_timeout; shorter system default overrides */
225 5*60, /* data timeout */
226 10*60, /* final timeout */
227 1024, /* size_addition */
228 5, /* hosts_max_try */
229 50, /* hosts_max_try_hardlimit */
230 TRUE, /* address_retry_include_sender */
231 FALSE, /* allow_localhost */
232 FALSE, /* authenticated_sender_force */
233 FALSE, /* gethostbyname */
234 TRUE, /* dns_qualify_single */
235 FALSE, /* dns_search_parents */
236 { NULL, NULL }, /* dnssec_domains {request,require} */
237 TRUE, /* delay_after_cutoff */
238 FALSE, /* hosts_override */
239 FALSE, /* hosts_randomize */
240 TRUE, /* keepalive */
241 FALSE, /* lmtp_ignore_quota */
242 NULL, /* expand_retry_include_ip_address */
243 TRUE /* retry_include_ip_address */
245 ,NULL /* socks_proxy */
248 ,NULL, /* tls_certificate */
250 NULL, /* tls_privatekey */
251 NULL, /* tls_require_ciphers */
253 US"system", /* tls_verify_certificates */
254 EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
255 /* tls_dh_min_bits */
256 TRUE, /* tls_tempfail_tryclear */
257 NULL, /* tls_verify_hosts */
258 US"*", /* tls_try_verify_hosts */
259 US"*" /* tls_verify_cert_hostnames */
262 , {NULL, /* dkim_canon */
263 NULL, /* dkim_domain */
264 NULL, /* dkim_private_key */
265 NULL, /* dkim_selector */
266 NULL, /* dkim_sign_headers */
267 NULL} /* dkim_strict */
271 /* some DSN flags for use later */
273 static int rf_list[] = {rf_notify_never, rf_notify_success,
274 rf_notify_failure, rf_notify_delay };
276 static uschar *rf_names[] = { US"NEVER", US"SUCCESS", US"FAILURE", US"DELAY" };
282 static uschar *smtp_command; /* Points to last cmd for error messages */
283 static uschar *mail_command; /* Points to MAIL cmd for error messages */
284 static BOOL update_waiting; /* TRUE to update the "wait" database */
287 /*************************************************
288 * Setup entry point *
289 *************************************************/
291 /* This function is called when the transport is about to be used,
292 but before running it in a sub-process. It is used for two things:
294 (1) To set the fallback host list in addresses, when delivering.
295 (2) To pass back the interface, port, protocol, and other options, for use
296 during callout verification.
299 tblock pointer to the transport instance block
300 addrlist list of addresses about to be transported
301 tf if not NULL, pointer to block in which to return options
302 uid the uid that will be set (not used)
303 gid the gid that will be set (not used)
304 errmsg place for error message (not used)
306 Returns: OK always (FAIL, DEFER not used)
310 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
311 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
313 smtp_transport_options_block *ob =
314 (smtp_transport_options_block *)(tblock->options_block);
316 errmsg = errmsg; /* Keep picky compilers happy */
320 /* Pass back options if required. This interface is getting very messy. */
324 tf->interface = ob->interface;
326 tf->protocol = ob->protocol;
327 tf->hosts = ob->hosts;
328 tf->hosts_override = ob->hosts_override;
329 tf->hosts_randomize = ob->hosts_randomize;
330 tf->gethostbyname = ob->gethostbyname;
331 tf->qualify_single = ob->dns_qualify_single;
332 tf->search_parents = ob->dns_search_parents;
333 tf->helo_data = ob->helo_data;
336 /* Set the fallback host list for all the addresses that don't have fallback
337 host lists, provided that the local host wasn't present in the original host
340 if (!testflag(addrlist, af_local_host_removed))
342 for (; addrlist != NULL; addrlist = addrlist->next)
343 if (addrlist->fallback_hosts == NULL)
344 addrlist->fallback_hosts = ob->fallback_hostlist;
352 /*************************************************
353 * Initialization entry point *
354 *************************************************/
356 /* Called for each instance, after its options have been read, to
357 enable consistency checks to be done, or anything else that needs
360 Argument: pointer to the transport instance block
365 smtp_transport_init(transport_instance *tblock)
367 smtp_transport_options_block *ob =
368 (smtp_transport_options_block *)(tblock->options_block);
370 /* Retry_use_local_part defaults FALSE if unset */
372 if (tblock->retry_use_local_part == TRUE_UNSET)
373 tblock->retry_use_local_part = FALSE;
375 /* Set the default port according to the protocol */
377 if (ob->port == NULL)
378 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
379 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
381 /* Set up the setup entry point, to be called before subprocesses for this
384 tblock->setup = smtp_transport_setup;
386 /* Complain if any of the timeouts are zero. */
388 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
389 ob->final_timeout <= 0)
390 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
391 "command, data, or final timeout value is zero for %s transport",
394 /* If hosts_override is set and there are local hosts, set the global
395 flag that stops verify from showing router hosts. */
397 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
399 /* If there are any fallback hosts listed, build a chain of host items
400 for them, but do not do any lookups at this time. */
402 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
409 /*************************************************
410 * Set delivery info into all active addresses *
411 *************************************************/
413 /* Only addresses whose status is >= PENDING are relevant. A lesser
414 status means that an address is not currently being processed.
417 addrlist points to a chain of addresses
418 errno_value to put in each address's errno field
419 msg to put in each address's message field
420 rc to put in each address's transport_return field
421 pass_message if TRUE, set the "pass message" flag in the address
422 host if set, mark addrs as having used this host
423 smtp_greeting from peer
424 helo_response from peer
426 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
427 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
428 this particular type of timeout.
434 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
435 BOOL pass_message, host_item * host
436 #ifdef EXPERIMENTAL_DSN_INFO
437 , const uschar * smtp_greeting, const uschar * helo_response
443 if (errno_value == ERRNO_CONNECTTIMEOUT)
445 errno_value = ETIMEDOUT;
446 orvalue = RTEF_CTOUT;
448 for (addr = addrlist; addr; addr = addr->next)
449 if (addr->transport_return >= PENDING)
451 addr->basic_errno = errno_value;
452 addr->more_errno |= orvalue;
456 if (pass_message) setflag(addr, af_pass_message);
458 addr->transport_return = rc;
461 addr->host_used = host;
462 #ifdef EXPERIMENTAL_DSN_INFO
464 {uschar * s = Ustrchr(smtp_greeting, '\n'); if (s) *s = '\0';}
465 addr->smtp_greeting = smtp_greeting;
468 {uschar * s = Ustrchr(helo_response, '\n'); if (s) *s = '\0';}
469 addr->helo_response = helo_response;
476 set_errno_nohost(address_item *addrlist, int errno_value, uschar *msg, int rc,
479 set_errno(addrlist, errno_value, msg, rc, pass_message, NULL
480 #ifdef EXPERIMENTAL_DSN_INFO
487 /*************************************************
488 * Check an SMTP response *
489 *************************************************/
491 /* This function is given an errno code and the SMTP response buffer
492 to analyse, together with the host identification for generating messages. It
493 sets an appropriate message and puts the first digit of the response code into
494 the yield variable. If no response was actually read, a suitable digit is
498 host the current host, to get its name for messages
499 errno_value pointer to the errno value
500 more_errno from the top address for use with ERRNO_FILTER_FAIL
501 buffer the SMTP response buffer
502 yield where to put a one-digit SMTP response code
503 message where to put an errror message
504 pass_message set TRUE if message is an SMTP response
506 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
510 check_response(host_item *host, int *errno_value, int more_errno,
511 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
515 if (smtp_use_pipelining &&
516 (Ustrcmp(smtp_command, "MAIL") == 0 ||
517 Ustrcmp(smtp_command, "RCPT") == 0 ||
518 Ustrcmp(smtp_command, "DATA") == 0))
521 *yield = '4'; /* Default setting is to give a temporary error */
523 /* Handle response timeout */
525 if (*errno_value == ETIMEDOUT)
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,
535 /* Handle malformed SMTP response */
537 if (*errno_value == ERRNO_SMTPFORMAT)
539 const uschar *malfresp = string_printing(buffer);
540 while (isspace(*malfresp)) malfresp++;
541 *message = *malfresp == 0
542 ? string_sprintf("Malformed SMTP reply (an empty line) "
543 "in response to %s%s", pl, smtp_command)
544 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
545 pl, smtp_command, malfresp);
549 /* Handle a failed filter process error; can't send QUIT as we mustn't
552 if (*errno_value == ERRNO_FILTER_FAIL)
554 *message = US string_sprintf("transport filter process failed (%d)%s",
556 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
560 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
563 if (*errno_value == ERRNO_CHHEADER_FAIL)
566 US string_sprintf("failed to expand headers_add or headers_remove: %s",
567 expand_string_message);
571 /* Handle failure to write a complete data block */
573 if (*errno_value == ERRNO_WRITEINCOMPLETE)
575 *message = US string_sprintf("failed to write a data block");
580 /* Handle lack of advertised SMTPUTF8, for international message */
581 if (*errno_value == ERRNO_UTF8_FWD)
583 *message = US string_sprintf("utf8 support required but not offered for forwarding");
584 DEBUG(D_deliver|D_transport) debug_printf("%s\n", *message);
589 /* Handle error responses from the remote mailer. */
593 const uschar *s = string_printing(buffer);
594 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
595 "%s", pl, smtp_command, s);
596 *pass_message = TRUE;
601 /* No data was read. If there is no errno, this must be the EOF (i.e.
602 connection closed) case, which causes deferral. An explicit connection reset
603 error has the same effect. Otherwise, put the host's identity in the message,
604 leaving the errno value to be interpreted as well. In all cases, we have to
605 assume the connection is now dead. */
607 if (*errno_value == 0 || *errno_value == ECONNRESET)
609 *errno_value = ERRNO_SMTPCLOSED;
610 *message = US string_sprintf("Remote host closed connection "
611 "in response to %s%s", pl, smtp_command);
613 else *message = US string_sprintf("%s [%s]", host->name, host->address);
620 /*************************************************
621 * Write error message to logs *
622 *************************************************/
624 /* This writes to the main log and to the message log.
627 addr the address item containing error information
628 host the current host
634 write_logs(address_item *addr, host_item *host)
636 uschar * message = string_sprintf("H=%s [%s]", host->name, host->address);
638 if (LOGGING(outgoing_port))
639 message = string_sprintf("%s:%d", message,
640 host->port == PORT_NONE ? 25 : host->port);
643 message = string_sprintf("%s: %s", message, addr->message);
644 if (addr->basic_errno > 0)
645 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
646 log_write(0, LOG_MAIN, "%s", message);
647 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
651 const uschar * s = exim_errstr(addr->basic_errno);
652 log_write(0, LOG_MAIN, "%s %s", message, s);
653 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), message, s);
658 msglog_line(host_item * host, uschar * message)
660 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
661 host->name, host->address, message);
666 #ifndef DISABLE_EVENT
667 /*************************************************
668 * Post-defer action *
669 *************************************************/
671 /* This expands an arbitrary per-transport string.
672 It might, for example, be used to write to the database log.
675 addr the address item containing error information
676 host the current host
682 deferred_event_raise(address_item *addr, host_item *host)
684 uschar * action = addr->transport->event_action;
685 const uschar * save_domain;
691 save_domain = deliver_domain;
692 save_local = deliver_localpart;
694 /*XXX would ip & port already be set up? */
695 deliver_host_address = string_copy(host->address);
696 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
697 event_defer_errno = addr->basic_errno;
699 router_name = addr->router->name;
700 transport_name = addr->transport->name;
701 deliver_domain = addr->domain;
702 deliver_localpart = addr->local_part;
704 (void) event_raise(action, US"msg:host:defer",
706 ? addr->basic_errno > 0
707 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
708 : string_copy(addr->message)
709 : addr->basic_errno > 0
710 ? string_copy(US strerror(addr->basic_errno))
713 deliver_localpart = save_local;
714 deliver_domain = save_domain;
715 router_name = transport_name = NULL;
719 /*************************************************
720 * Synchronize SMTP responses *
721 *************************************************/
723 /* This function is called from smtp_deliver() to receive SMTP responses from
724 the server, and match them up with the commands to which they relate. When
725 PIPELINING is not in use, this function is called after every command, and is
726 therefore somewhat over-engineered, but it is simpler to use a single scheme
727 that works both with and without PIPELINING instead of having two separate sets
730 The set of commands that are buffered up with pipelining may start with MAIL
731 and may end with DATA; in between are RCPT commands that correspond to the
732 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
733 etc.) are never buffered.
735 Errors after MAIL or DATA abort the whole process leaving the response in the
736 buffer. After MAIL, pending responses are flushed, and the original command is
737 re-instated in big_buffer for error messages. For RCPT commands, the remote is
738 permitted to reject some recipient addresses while accepting others. However
739 certain errors clearly abort the whole process. Set the value in
740 transport_return to PENDING_OK if the address is accepted. If there is a
741 subsequent general error, it will get reset accordingly. If not, it will get
742 converted to OK at the end.
745 addrlist the complete address list
746 include_affixes TRUE if affixes include in RCPT
747 sync_addr ptr to the ptr of the one to start scanning at (updated)
748 host the host we are connected to
749 count the number of responses to read
751 include_sender true if 4xx retry is to include the sender it its key
752 pending_MAIL true if the first response is for MAIL
753 pending_DATA 0 if last command sent was not DATA
754 +1 if previously had a good recipient
755 -1 if not previously had a good recipient
756 inblock incoming SMTP block
757 timeout timeout value
758 buffer buffer for reading response
759 buffsize size of buffer
761 Returns: 3 if at least one address had 2xx and one had 5xx
762 2 if at least one address had 5xx but none had 2xx
763 1 if at least one host had a 2xx response, but none had 5xx
764 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
765 -1 timeout while reading RCPT response
766 -2 I/O or other non-response error for RCPT
767 -3 DATA or MAIL failed - errno and buffer set
771 sync_responses(address_item *addrlist, BOOL include_affixes,
772 address_item **sync_addr, host_item *host, int count,
773 BOOL address_retry_include_sender, BOOL pending_MAIL,
774 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
777 address_item *addr = *sync_addr;
780 /* Handle the response for a MAIL command. On error, reinstate the original
781 command in big_buffer for error message use, and flush any further pending
782 responses before returning, except after I/O errors and timeouts. */
787 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
789 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
790 if (errno == 0 && buffer[0] != 0)
792 uschar flushbuffer[4096];
794 if (buffer[0] == '4')
796 save_errno = ERRNO_MAIL4XX;
797 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
801 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
803 && (errno != 0 || flushbuffer[0] == 0))
809 if (pending_DATA) count--; /* Number of RCPT responses to come */
810 while (count-- > 0) /* Mark any pending addrs with the host used */
812 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
813 addr->host_used = host;
820 if (pending_DATA) count--; /* Number of RCPT responses to come */
822 /* Read and handle the required number of RCPT responses, matching each one up
823 with an address by scanning for the next address whose status is PENDING_DEFER.
828 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
830 /* The address was accepted */
831 addr->host_used = host;
833 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
836 addr->transport_return = PENDING_OK;
838 /* If af_dr_retry_exists is set, there was a routing delay on this address;
839 ensure that any address-specific retry record is expunged. We do this both
840 for the basic key and for the version that also includes the sender. */
842 if (testflag(addr, af_dr_retry_exists))
844 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
846 retry_add_item(addr, altkey, rf_delete);
847 retry_add_item(addr, addr->address_retry_key, rf_delete);
851 /* Timeout while reading the response */
853 else if (errno == ETIMEDOUT)
855 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
856 transport_rcpt_address(addr, include_affixes));
857 set_errno_nohost(addrlist, ETIMEDOUT, message, DEFER, FALSE);
858 retry_add_item(addr, addr->address_retry_key, 0);
859 update_waiting = FALSE;
863 /* Handle other errors in obtaining an SMTP response by returning -1. This
864 will cause all the addresses to be deferred. Restore the SMTP command in
865 big_buffer for which we are checking the response, so the error message
868 else if (errno != 0 || buffer[0] == 0)
870 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
871 transport_rcpt_address(addr, include_affixes));
875 /* Handle SMTP permanent and temporary response codes. */
880 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
881 "%s", transport_rcpt_address(addr, include_affixes),
882 string_printing(buffer));
883 setflag(addr, af_pass_message);
884 msglog_line(host, addr->message);
886 /* The response was 5xx */
888 if (buffer[0] == '5')
890 addr->transport_return = FAIL;
894 /* The response was 4xx */
898 addr->transport_return = DEFER;
899 addr->basic_errno = ERRNO_RCPT4XX;
900 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
902 #ifndef DISABLE_EVENT
903 event_defer_errno = addr->more_errno;
904 msg_event_raise(US"msg:rcpt:host:defer", addr);
907 /* Log temporary errors if there are more hosts to be tried.
908 If not, log this last one in the == line. */
911 log_write(0, LOG_MAIN, "H=%s [%s]: %s", host->name, host->address, addr->message);
913 #ifndef DISABLE_EVENT
915 msg_event_raise(US"msg:rcpt:defer", addr);
918 /* Do not put this message on the list of those waiting for specific
919 hosts, as otherwise it is likely to be tried too often. */
921 update_waiting = FALSE;
923 /* Add a retry item for the address so that it doesn't get tried again
924 too soon. If address_retry_include_sender is true, add the sender address
927 if (address_retry_include_sender)
929 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
931 retry_add_item(addr, altkey, 0);
933 else retry_add_item(addr, addr->address_retry_key, 0);
936 } /* Loop for next RCPT response */
938 /* Update where to start at for the next block of responses, unless we
939 have already handled all the addresses. */
941 if (addr != NULL) *sync_addr = addr->next;
943 /* Handle a response to DATA. If we have not had any good recipients, either
944 previously or in this block, the response is ignored. */
946 if (pending_DATA != 0 &&
947 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
952 if (pending_DATA > 0 || (yield & 1) != 0)
954 if (errno == 0 && buffer[0] == '4')
956 errno = ERRNO_DATA4XX;
957 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
961 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
962 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
963 "is in use and there were no good recipients\n", msg);
966 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
967 present) received 3xx. If any RCPTs were handled and yielded anything other
968 than 4xx, yield will be set non-zero. */
975 /* Do the client side of smtp-level authentication */
978 buffer EHLO response from server (gets overwritten)
979 addrlist chain of potential addresses to deliver
980 host host to deliver to
982 ibp, obp comms channel control blocks
985 OK Success, or failed (but not required): global "smtp_authenticated" set
986 DEFER Failed authentication (and was required)
987 ERROR Internal problem
989 FAIL_SEND Failed communications - transmit
994 smtp_auth(uschar *buffer, unsigned bufsize, address_item *addrlist, host_item *host,
995 smtp_transport_options_block *ob, BOOL is_esmtp,
996 smtp_inblock *ibp, smtp_outblock *obp)
999 uschar *fail_reason = US"server did not advertise AUTH support";
1001 smtp_authenticated = FALSE;
1002 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
1003 require_auth = verify_check_given_host(&ob->hosts_require_auth, host);
1005 if (is_esmtp && !regex_AUTH) regex_AUTH =
1006 regex_must_compile(US"\\n250[\\s\\-]AUTH\\s+([\\-\\w\\s]+)(?:\\n|$)",
1009 if (is_esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
1011 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
1012 expand_nmax = -1; /* reset */
1014 /* Must not do this check until after we have saved the result of the
1015 regex match above. */
1017 if (require_auth == OK ||
1018 verify_check_given_host(&ob->hosts_try_auth, host) == OK)
1021 fail_reason = US"no common mechanisms were found";
1023 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1025 /* Scan the configured authenticators looking for one which is configured
1026 for use as a client, which is not suppressed by client_condition, and
1027 whose name matches an authentication mechanism supported by the server.
1028 If one is found, attempt to authenticate by calling its client function.
1031 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1035 (au->client_condition != NULL &&
1036 !expand_check_condition(au->client_condition, au->name,
1037 US"client authenticator")))
1039 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1041 (au->client)? "client_condition is false" :
1042 "not configured as a client");
1046 /* Loop to scan supported server mechanisms */
1051 int len = Ustrlen(au->public_name);
1052 while (isspace(*p)) p++;
1054 if (strncmpic(au->public_name, p, len) != 0 ||
1055 (p[len] != 0 && !isspace(p[len])))
1057 while (*p != 0 && !isspace(*p)) p++;
1061 /* Found data for a listed mechanism. Call its client entry. Set
1062 a flag in the outblock so that data is overwritten after sending so
1063 that reflections don't show it. */
1065 fail_reason = US"authentication attempt(s) failed";
1066 obp->authenticating = TRUE;
1067 rc = (au->info->clientcode)(au, ibp, obp,
1068 ob->command_timeout, buffer, bufsize);
1069 obp->authenticating = FALSE;
1070 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1073 /* A temporary authentication failure must hold up delivery to
1074 this host. After a permanent authentication failure, we carry on
1075 to try other authentication methods. If all fail hard, try to
1076 deliver the message unauthenticated unless require_auth was set. */
1081 smtp_authenticated = TRUE; /* stops the outer loop */
1082 client_authenticator = au->name;
1083 if (au->set_client_id != NULL)
1084 client_authenticated_id = expand_string(au->set_client_id);
1087 /* Failure after writing a command */
1092 /* Failure after reading a response */
1095 if (errno != 0 || buffer[0] != '5') return FAIL;
1096 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1097 au->name, host->name, host->address, buffer);
1100 /* Failure by some other means. In effect, the authenticator
1101 decided it wasn't prepared to handle this case. Typically this
1102 is the result of "fail" in an expansion string. Do we need to
1103 log anything here? Feb 2006: a message is now put in the buffer
1104 if logging is required. */
1108 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1109 "authentication H=%s [%s] %s", au->name, host->name,
1110 host->address, buffer);
1113 /* Internal problem, message in buffer. */
1116 set_errno_nohost(addrlist, ERRNO_AUTHPROB, string_copy(buffer),
1121 break; /* If not authenticated, try next authenticator */
1122 } /* Loop for scanning supported server mechanisms */
1123 } /* Loop for further authenticators */
1127 /* If we haven't authenticated, but are required to, give up. */
1129 if (require_auth == OK && !smtp_authenticated)
1131 set_errno_nohost(addrlist, ERRNO_AUTHFAIL,
1132 string_sprintf("authentication required but %s", fail_reason), DEFER,
1141 /* Construct AUTH appendix string for MAIL TO */
1144 buffer to build string
1145 addrlist chain of potential addresses to deliver
1146 ob transport options
1148 Globals smtp_authenticated
1149 client_authenticated_sender
1150 Return True on error, otherwise buffer has (possibly empty) terminated string
1154 smtp_mail_auth_str(uschar *buffer, unsigned bufsize, address_item *addrlist,
1155 smtp_transport_options_block *ob)
1157 uschar *local_authenticated_sender = authenticated_sender;
1160 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n", authenticated_sender, ob->authenticated_sender, smtp_authenticated?"Y":"N");
1163 if (ob->authenticated_sender != NULL)
1165 uschar *new = expand_string(ob->authenticated_sender);
1168 if (!expand_string_forcedfail)
1170 uschar *message = string_sprintf("failed to expand "
1171 "authenticated_sender: %s", expand_string_message);
1172 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1176 else if (new[0] != 0) local_authenticated_sender = new;
1179 /* Add the authenticated sender address if present */
1181 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1182 local_authenticated_sender != NULL)
1184 string_format(buffer, bufsize, " AUTH=%s",
1185 auth_xtextencode(local_authenticated_sender,
1186 Ustrlen(local_authenticated_sender)));
1187 client_authenticated_sender = string_copy(local_authenticated_sender);
1197 #ifdef EXPERIMENTAL_DANE
1198 /* Lookup TLSA record for host/port.
1199 Return: OK success with dnssec; DANE mode
1200 DEFER Do not use this host now, may retry later
1201 FAIL_FORCED No TLSA record; DANE not usable
1202 FAIL Do not use this connection
1206 tlsa_lookup(const host_item * host, dns_answer * dnsa, BOOL dane_required)
1208 /* move this out to host.c given the similarity to dns_lookup() ? */
1210 const uschar * fullname = buffer;
1212 /* TLSA lookup string */
1213 (void)sprintf(CS buffer, "_%d._tcp.%.256s", host->port, host->name);
1215 switch (dns_lookup(dnsa, buffer, T_TLSA, &fullname))
1218 if (!dns_is_secure(dnsa))
1220 log_write(0, LOG_MAIN, "DANE error: TLSA lookup not DNSSEC");
1226 return DEFER; /* just defer this TLS'd conn */
1229 return dane_required ? FAIL : FAIL_FORCED;
1233 return dane_required ? FAIL : DEFER;
1240 typedef struct smtp_compare_s
1242 uschar *current_sender_address;
1243 struct transport_instance *tblock;
1247 Create a unique string that identifies this message, it is based on
1248 sender_address, helo_data and tls_certificate if enabled. */
1251 smtp_local_identity(uschar * sender, struct transport_instance * tblock)
1253 address_item * addr1;
1254 uschar * if1 = US"";
1255 uschar * helo1 = US"";
1257 uschar * tlsc1 = US"";
1259 uschar * save_sender_address = sender_address;
1260 uschar * local_identity = NULL;
1261 smtp_transport_options_block * ob =
1262 (smtp_transport_options_block *)tblock->options_block;
1264 sender_address = sender;
1266 addr1 = deliver_make_addr (sender, TRUE);
1267 deliver_set_expansions(addr1);
1270 if1 = expand_string(ob->interface);
1273 helo1 = expand_string(ob->helo_data);
1276 if (ob->tls_certificate)
1277 tlsc1 = expand_string(ob->tls_certificate);
1278 local_identity = string_sprintf ("%s^%s^%s", if1, helo1, tlsc1);
1280 local_identity = string_sprintf ("%s^%s", if1, helo1);
1283 deliver_set_expansions(NULL);
1284 sender_address = save_sender_address;
1286 return local_identity;
1291 /* This routine is a callback that is called from transport_check_waiting.
1292 This function will evaluate the incoming message versus the previous
1293 message. If the incoming message is using a different local identity then
1294 we will veto this new message. */
1297 smtp_are_same_identities(uschar * message_id, smtp_compare_t * s_compare)
1299 uschar * message_local_identity,
1300 * current_local_identity,
1301 * new_sender_address;
1303 current_local_identity =
1304 smtp_local_identity(s_compare->current_sender_address, s_compare->tblock);
1306 if (!(new_sender_address = deliver_get_sender_address(message_id)))
1309 message_local_identity =
1310 smtp_local_identity(new_sender_address, s_compare->tblock);
1312 return Ustrcmp(current_local_identity, message_local_identity) == 0;
1318 ehlo_response(uschar * buf, size_t bsize, uschar checks)
1321 if ( checks & PEER_OFFERED_TLS
1322 && pcre_exec(regex_STARTTLS, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1323 checks &= ~PEER_OFFERED_TLS;
1326 if ( checks & PEER_OFFERED_IGNQ
1327 && pcre_exec(regex_IGNOREQUOTA, NULL, CS buf, bsize, 0,
1328 PCRE_EOPT, NULL, 0) < 0)
1329 checks &= ~PEER_OFFERED_IGNQ;
1331 if ( checks & PEER_OFFERED_CHUNKING
1332 && pcre_exec(regex_CHUNKING, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1333 checks &= ~PEER_OFFERED_CHUNKING;
1335 #ifndef DISABLE_PRDR
1336 if ( checks & PEER_OFFERED_PRDR
1337 && pcre_exec(regex_PRDR, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1338 checks &= ~PEER_OFFERED_PRDR;
1342 if ( checks & PEER_OFFERED_UTF8
1343 && pcre_exec(regex_UTF8, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1344 checks &= ~PEER_OFFERED_UTF8;
1347 if ( checks & PEER_OFFERED_DSN
1348 && pcre_exec(regex_DSN, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1349 checks &= ~PEER_OFFERED_DSN;
1351 if ( checks & PEER_OFFERED_PIPE
1352 && pcre_exec(regex_PIPELINING, NULL, CS buf, bsize, 0,
1353 PCRE_EOPT, NULL, 0) < 0)
1354 checks &= ~PEER_OFFERED_PIPE;
1356 if ( checks & PEER_OFFERED_SIZE
1357 && pcre_exec(regex_SIZE, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1358 checks &= ~PEER_OFFERED_SIZE;
1364 /*************************************************
1365 * Deliver address list to given host *
1366 *************************************************/
1368 /* If continue_hostname is not null, we get here only when continuing to
1369 deliver down an existing channel. The channel was passed as the standard
1370 input. TLS is never active on a passed channel; the previous process always
1371 closes it down before passing the connection on.
1373 Otherwise, we have to make a connection to the remote host, and do the
1374 initial protocol exchange.
1376 When running as an MUA wrapper, if the sender or any recipient is rejected,
1377 temporarily or permanently, we force failure for all recipients.
1380 addrlist chain of potential addresses to deliver; only those whose
1381 transport_return field is set to PENDING_DEFER are currently
1382 being processed; others should be skipped - they have either
1383 been delivered to an earlier host or IP address, or been
1384 failed by one of them.
1385 host host to deliver to
1386 host_af AF_INET or AF_INET6
1387 port default TCP/IP port to use, in host byte order
1388 interface interface to bind to, or NULL
1389 tblock transport instance block
1390 message_defer set TRUE if yield is OK, but all addresses were deferred
1391 because of a non-recipient, non-host failure, that is, a
1392 4xx response to MAIL FROM, DATA, or ".". This is a defer
1393 that is specific to the message.
1394 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1395 a second attempt after TLS initialization fails
1397 Returns: OK - the connection was made and the delivery attempted;
1398 the result for each address is in its data block.
1399 DEFER - the connection could not be made, or something failed
1400 while setting up the SMTP session, or there was a
1401 non-message-specific error, such as a timeout.
1402 ERROR - a filter command is specified for this transport,
1403 and there was a problem setting it up; OR helo_data
1404 or add_headers or authenticated_sender is specified
1405 for this transport, and the string failed to expand
1409 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
1410 uschar *interface, transport_instance *tblock,
1411 BOOL *message_defer, BOOL suppress_tls)
1414 address_item *sync_addr;
1415 address_item *first_addr = addrlist;
1420 time_t start_delivery_time = time(NULL);
1421 smtp_transport_options_block *ob =
1422 (smtp_transport_options_block *)(tblock->options_block);
1423 BOOL lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
1424 BOOL smtps = strcmpic(ob->protocol, US"smtps") == 0;
1426 BOOL send_rset = TRUE;
1427 BOOL send_quit = TRUE;
1428 BOOL setting_up = TRUE;
1429 BOOL completed_address = FALSE;
1432 BOOL pass_message = FALSE;
1433 uschar peer_offered = 0; /*XXX should this be handed on cf. tls_offered, smtp_use_dsn ? */
1434 #ifndef DISABLE_PRDR
1438 BOOL utf8_needed = FALSE;
1440 BOOL dsn_all_lasthop = TRUE;
1441 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1443 BOOL dane_required = verify_check_given_host(&ob->hosts_require_dane, host) == OK;
1444 dns_answer tlsa_dnsa;
1446 smtp_inblock inblock;
1447 smtp_outblock outblock;
1448 int max_rcpt = tblock->max_addresses;
1449 uschar *igquotstr = US"";
1451 #ifdef EXPERIMENTAL_DSN_INFO
1452 uschar *smtp_greeting = NULL;
1453 uschar *helo_response = NULL;
1455 uschar *helo_data = NULL;
1457 uschar *message = NULL;
1458 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
1460 uschar buffer[4096];
1461 uschar inbuffer[4096];
1462 uschar outbuffer[4096];
1464 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
1466 *message_defer = FALSE;
1467 smtp_command = US"initial connection";
1468 if (max_rcpt == 0) max_rcpt = 999999;
1470 /* Set up the buffer for reading SMTP response packets. */
1472 inblock.buffer = inbuffer;
1473 inblock.buffersize = sizeof(inbuffer);
1474 inblock.ptr = inbuffer;
1475 inblock.ptrend = inbuffer;
1477 /* Set up the buffer for holding SMTP commands while pipelining */
1479 outblock.buffer = outbuffer;
1480 outblock.buffersize = sizeof(outbuffer);
1481 outblock.ptr = outbuffer;
1482 outblock.cmd_count = 0;
1483 outblock.authenticating = FALSE;
1485 /* Reset the parameters of a TLS session. */
1488 tls_out.cipher = NULL; /* the one we may use for this transport */
1489 tls_out.ourcert = NULL;
1490 tls_out.peercert = NULL;
1491 tls_out.peerdn = NULL;
1492 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1495 tls_out.ocsp = OCSP_NOT_REQ;
1497 /* Flip the legacy TLS-related variables over to the outbound set in case
1498 they're used in the context of the transport. Don't bother resetting
1499 afterward as we're in a subprocess. */
1501 tls_modify_variables(&tls_out);
1506 set_errno_nohost(addrlist, ERRNO_TLSFAILURE, US"TLS support not available",
1512 /* Make a connection to the host if this isn't a continued delivery, and handle
1513 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
1514 specially so they can be identified for retries. */
1516 if (continue_hostname == NULL)
1518 /* This puts port into host->port */
1519 inblock.sock = outblock.sock =
1520 smtp_connect(host, host_af, port, interface, ob->connect_timeout, tblock);
1522 if (inblock.sock < 0)
1524 set_errno_nohost(addrlist, (errno == ETIMEDOUT)? ERRNO_CONNECTTIMEOUT : errno,
1525 NULL, DEFER, FALSE);
1529 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1531 tls_out.dane_verified = FALSE;
1532 tls_out.tlsa_usage = 0;
1534 if (host->dnssec == DS_YES)
1537 || verify_check_given_host(&ob->hosts_try_dane, host) == OK
1539 switch (rc = tlsa_lookup(host, &tlsa_dnsa, dane_required))
1541 case OK: dane = TRUE; break;
1542 case FAIL_FORCED: break;
1543 default: set_errno_nohost(addrlist, ERRNO_DNSDEFER,
1544 string_sprintf("DANE error: tlsa lookup %s",
1545 rc == DEFER ? "DEFER" : "FAIL"),
1550 else if (dane_required)
1552 set_errno_nohost(addrlist, ERRNO_DNSDEFER,
1553 string_sprintf("DANE error: %s lookup not DNSSEC", host->name),
1559 ob->tls_tempfail_tryclear = FALSE;
1563 /* Expand the greeting message while waiting for the initial response. (Makes
1564 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1565 delayed till here so that $sending_interface and $sending_port are set. */
1567 helo_data = expand_string(ob->helo_data);
1571 uschar * errstr = NULL;
1572 if ((helo_data = string_domain_utf8_to_alabel(helo_data, &errstr)), errstr)
1574 errstr = string_sprintf("failed to expand helo_data: %s", errstr);
1575 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE);
1582 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1583 is nevertheless a reasonably clean way of programming this kind of logic,
1584 where you want to escape on any error. */
1588 BOOL good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
1589 '2', ob->command_timeout);
1590 #ifdef EXPERIMENTAL_DSN_INFO
1591 smtp_greeting = string_copy(buffer);
1593 if (!good_response) goto RESPONSE_FAILED;
1595 #ifndef DISABLE_EVENT
1598 lookup_dnssec_authenticated = host->dnssec==DS_YES ? US"yes"
1599 : host->dnssec==DS_NO ? US"no" : NULL;
1600 s = event_raise(tblock->event_action, US"smtp:connect", buffer);
1603 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL,
1604 string_sprintf("deferred by smtp:connect event expansion: %s", s),
1612 /* Now check if the helo_data expansion went well, and sign off cleanly if
1615 if (helo_data == NULL)
1617 uschar *message = string_sprintf("failed to expand helo_data: %s",
1618 expand_string_message);
1619 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1625 /** Debugging without sending a message
1626 addrlist->transport_return = DEFER;
1630 /* Errors that occur after this point follow an SMTP command, which is
1631 left in big_buffer by smtp_write_command() for use in error messages. */
1633 smtp_command = big_buffer;
1635 /* Tell the remote who we are...
1637 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1638 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1639 greeting is of this form. The assumption was that the far end supports it
1640 properly... but experience shows that there are some that give 5xx responses,
1641 even though the banner includes "ESMTP" (there's a bloody-minded one that
1642 says "ESMTP not spoken here"). Cope with that case.
1644 September 2000: Time has passed, and it seems reasonable now to always send
1645 EHLO at the start. It is also convenient to make the change while installing
1648 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1649 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1650 would be no way to send out the mails, so there is now a host list
1651 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1652 PIPELINING problem as well. Maybe it can also be useful to cure other
1653 problems with broken servers.
1655 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1656 Then somebody tried it with a Microsoft mailer... It seems that all other
1657 mailers use upper case for some reason (the RFC is quite clear about case
1658 independence) so, for peace of mind, I gave in. */
1660 esmtp = verify_check_given_host(&ob->hosts_avoid_esmtp, host) != OK;
1662 /* Alas; be careful, since this goto is not an error-out, so conceivably
1663 we might set data between here and the target which we assume to exist
1664 and be usable. I can see this coming back to bite us. */
1669 suppress_tls = FALSE;
1670 ob->tls_tempfail_tryclear = FALSE;
1671 smtp_command = US"SSL-on-connect";
1678 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1679 lmtp? "LHLO" : "EHLO", helo_data) < 0)
1681 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1682 ob->command_timeout))
1684 if (errno != 0 || buffer[0] == 0 || lmtp)
1686 #ifdef EXPERIMENTAL_DSN_INFO
1687 helo_response = string_copy(buffer);
1689 goto RESPONSE_FAILED;
1693 #ifdef EXPERIMENTAL_DSN_INFO
1694 helo_response = string_copy(buffer);
1700 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1707 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1709 good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
1710 '2', ob->command_timeout);
1711 #ifdef EXPERIMENTAL_DSN_INFO
1712 helo_response = string_copy(buffer);
1714 if (!good_response) goto RESPONSE_FAILED;
1718 peer_offered = ehlo_response(buffer, Ustrlen(buffer),
1719 PEER_OFFERED_TLS /* others checked later */
1722 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1725 tls_offered = !!(peer_offered & PEER_OFFERED_TLS);
1729 /* For continuing deliveries down the same channel, the socket is the standard
1730 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1731 below). Set up the pointer to where subsequent commands will be left, for
1732 error messages. Note that smtp_use_size and smtp_use_pipelining will have been
1733 set from the command line if they were set in the process that passed the
1736 /*XXX continue case needs to propagate DSN_INFO, prob. in deliver.c
1737 as the contine goes via transport_pass_socket() and doublefork and exec.
1738 It does not wait. Unclear how we keep separate host's responses
1739 separate - we could match up by host ip+port as a bodge. */
1743 inblock.sock = outblock.sock = fileno(stdin);
1744 smtp_command = big_buffer;
1745 host->port = port; /* Record the port that was used */
1748 /* If TLS is available on this connection, whether continued or not, attempt to
1749 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1750 send another EHLO - the server may give a different answer in secure mode. We
1751 use a separate buffer for reading the response to STARTTLS so that if it is
1752 negative, the original EHLO data is available for subsequent analysis, should
1753 the client not be required to use TLS. If the response is bad, copy the buffer
1754 for error analysis. */
1759 && verify_check_given_host(&ob->hosts_avoid_tls, host) != OK)
1761 uschar buffer2[4096];
1762 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1765 /* If there is an I/O error, transmission of this message is deferred. If
1766 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1767 false, we also defer. However, if there is a temporary rejection of STARTTLS
1768 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1769 STARTTLS, we carry on. This means we will try to send the message in clear,
1770 unless the host is in hosts_require_tls (tested below). */
1772 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1773 ob->command_timeout))
1777 || (buffer2[0] == '4' && !ob->tls_tempfail_tryclear)
1780 Ustrncpy(buffer, buffer2, sizeof(buffer));
1781 goto RESPONSE_FAILED;
1785 /* STARTTLS accepted: try to negotiate a TLS session. */
1790 int rc = tls_client_start(inblock.sock, host, addrlist, tblock
1791 # ifdef EXPERIMENTAL_DANE
1792 , dane ? &tlsa_dnsa : NULL
1796 /* TLS negotiation failed; give an error. From outside, this function may
1797 be called again to try in clear on a new connection, if the options permit
1798 it for this host. */
1802 # ifdef EXPERIMENTAL_DANE
1803 if (rc == DEFER && dane)
1805 log_write(0, LOG_MAIN,
1806 "DANE attempt failed; no TLS connection to %s [%s]",
1807 host->name, host->address);
1811 save_errno = ERRNO_TLSFAILURE;
1812 message = US"failure while setting up TLS session";
1817 /* TLS session is set up */
1819 for (addr = addrlist; addr; addr = addr->next)
1820 if (addr->transport_return == PENDING_DEFER)
1822 addr->cipher = tls_out.cipher;
1823 addr->ourcert = tls_out.ourcert;
1824 addr->peercert = tls_out.peercert;
1825 addr->peerdn = tls_out.peerdn;
1826 addr->ocsp = tls_out.ocsp;
1831 /* if smtps, we'll have smtp_command set to something else; always safe to
1833 smtp_command = big_buffer;
1835 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1836 helo_data is null, we are dealing with a connection that was passed from
1837 another process, and so we won't have expanded helo_data above. We have to
1838 expand it here. $sending_ip_address and $sending_port are set up right at the
1839 start of the Exim process (in exim.c). */
1841 if (tls_out.active >= 0)
1846 if (helo_data == NULL)
1848 helo_data = expand_string(ob->helo_data);
1849 if (helo_data == NULL)
1851 uschar *message = string_sprintf("failed to expand helo_data: %s",
1852 expand_string_message);
1853 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1859 /* For SMTPS we need to wait for the initial OK response. */
1862 good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
1863 '2', ob->command_timeout);
1864 #ifdef EXPERIMENTAL_DSN_INFO
1865 smtp_greeting = string_copy(buffer);
1867 if (!good_response) goto RESPONSE_FAILED;
1871 greeting_cmd = "EHLO";
1874 greeting_cmd = "HELO";
1876 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1879 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1880 lmtp? "LHLO" : greeting_cmd, helo_data) < 0)
1882 good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
1883 '2', ob->command_timeout);
1884 #ifdef EXPERIMENTAL_DSN_INFO
1885 helo_response = string_copy(buffer);
1887 if (!good_response) goto RESPONSE_FAILED;
1890 /* If the host is required to use a secure channel, ensure that we
1894 # ifdef EXPERIMENTAL_DANE
1897 || verify_check_given_host(&ob->hosts_require_tls, host) == OK
1900 save_errno = ERRNO_TLSREQUIRED;
1901 message = string_sprintf("a TLS session is required, but %s",
1902 tls_offered ? "an attempt to start TLS failed"
1903 : "the server did not offer TLS support");
1906 #endif /*SUPPORT_TLS*/
1908 /* If TLS is active, we have just started it up and re-done the EHLO command,
1909 so its response needs to be analyzed. If TLS is not active and this is a
1910 continued session down a previously-used socket, we haven't just done EHLO, so
1913 if (continue_hostname == NULL
1915 || tls_out.active >= 0
1920 peer_offered = ehlo_response(buffer, Ustrlen(buffer),
1922 | (lmtp && ob->lmtp_ignore_quota ? PEER_OFFERED_IGNQ : 0)
1923 | PEER_OFFERED_CHUNKING
1926 | (addrlist->prop.utf8_msg ? PEER_OFFERED_UTF8 : 0)
1927 /*XXX if we hand peercaps on to continued-conn processes,
1928 must not depend on this addr */
1932 | (ob->size_addition >= 0 ? PEER_OFFERED_SIZE : 0)
1935 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
1936 lmtp_ignore_quota option was set. */
1938 igquotstr = peer_offered & PEER_OFFERED_IGNQ ? US" IGNOREQUOTA" : US"";
1940 /* If the response to EHLO specified support for the SIZE parameter, note
1941 this, provided size_addition is non-negative. */
1943 smtp_use_size = !!(peer_offered & PEER_OFFERED_SIZE);
1945 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
1946 the current host, esmtp will be false, so PIPELINING can never be used. If
1947 the current host matches hosts_avoid_pipelining, don't do it. */
1949 smtp_use_pipelining = peer_offered & PEER_OFFERED_PIPE
1950 && verify_check_given_host(&ob->hosts_avoid_pipelining, host) != OK;
1952 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
1953 smtp_use_pipelining ? "" : "not ");
1955 if ( peer_offered & PEER_OFFERED_CHUNKING
1956 && verify_check_given_host(&ob->hosts_try_chunking, host) != OK)
1957 peer_offered &= ~PEER_OFFERED_CHUNKING;
1959 if (peer_offered & PEER_OFFERED_CHUNKING)
1960 {DEBUG(D_transport) debug_printf("CHUNKING usable\n");}
1962 #ifndef DISABLE_PRDR
1963 if ( peer_offered & PEER_OFFERED_PRDR
1964 && verify_check_given_host(&ob->hosts_try_prdr, host) != OK)
1965 peer_offered &= ~PEER_OFFERED_PRDR;
1967 if (peer_offered & PEER_OFFERED_PRDR)
1968 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1971 /* Note if the server supports DSN */
1972 smtp_use_dsn = !!(peer_offered & PEER_OFFERED_DSN);
1973 DEBUG(D_transport) debug_printf("%susing DSN\n", smtp_use_dsn ? "" : "not ");
1975 /* Note if the response to EHLO specifies support for the AUTH extension.
1976 If it has, check that this host is one we want to authenticate to, and do
1977 the business. The host name and address must be available when the
1978 authenticator's client driver is running. */
1980 switch (yield = smtp_auth(buffer, sizeof(buffer), addrlist, host,
1981 ob, esmtp, &inblock, &outblock))
1983 default: goto SEND_QUIT;
1985 case FAIL_SEND: goto SEND_FAILED;
1986 case FAIL: goto RESPONSE_FAILED;
1990 /* The setting up of the SMTP call is now complete. Any subsequent errors are
1991 message-specific. */
1996 if (addrlist->prop.utf8_msg)
1998 utf8_needed = !addrlist->prop.utf8_downcvt
1999 && !addrlist->prop.utf8_downcvt_maybe;
2000 DEBUG(D_transport) if (!utf8_needed) debug_printf("utf8: %s downconvert\n",
2001 addrlist->prop.utf8_downcvt ? "mandatory" : "optional");
2004 /* If this is an international message we need the host to speak SMTPUTF8 */
2005 if (utf8_needed && !(peer_offered & PEER_OFFERED_UTF8))
2007 errno = ERRNO_UTF8_FWD;
2008 goto RESPONSE_FAILED;
2012 /* If there is a filter command specified for this transport, we can now
2013 set it up. This cannot be done until the identify of the host is known. */
2015 if (tblock->filter_command != NULL)
2019 sprintf(CS buffer, "%.50s transport", tblock->name);
2020 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
2021 TRUE, DEFER, addrlist, buffer, NULL);
2022 transport_filter_timeout = tblock->filter_timeout;
2024 /* On failure, copy the error to all addresses, abandon the SMTP call, and
2029 set_errno_nohost(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
2037 /* For messages that have more than the maximum number of envelope recipients,
2038 we want to send several transactions down the same SMTP connection. (See
2039 comments in deliver.c as to how this reconciles, heuristically, with
2040 remote_max_parallel.) This optimization was added to Exim after the following
2041 code was already working. The simplest way to put it in without disturbing the
2042 code was to use a goto to jump back to this point when there is another
2043 transaction to handle. */
2046 sync_addr = first_addr;
2050 completed_address = FALSE;
2053 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
2054 qualification, send it, adding something to the message size to allow for
2055 imprecision and things that get added en route. Exim keeps the number of lines
2056 in a message, so we can give an accurate value for the original message, but we
2057 need some additional to handle added headers. (Double "." characters don't get
2058 included in the count.) */
2065 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
2069 #ifndef DISABLE_PRDR
2070 prdr_active = FALSE;
2071 if (peer_offered & PEER_OFFERED_PRDR)
2072 for (addr = first_addr; addr; addr = addr->next)
2073 if (addr->transport_return == PENDING_DEFER)
2075 for (addr = addr->next; addr; addr = addr->next)
2076 if (addr->transport_return == PENDING_DEFER)
2077 { /* at least two recipients to send */
2079 sprintf(CS p, " PRDR"); p += 5;
2087 if ( addrlist->prop.utf8_msg
2088 && !addrlist->prop.utf8_downcvt
2089 && peer_offered & PEER_OFFERED_UTF8
2091 sprintf(CS p, " SMTPUTF8"), p += 9;
2094 /* check if all addresses have lasthop flag */
2095 /* do not send RET and ENVID if true */
2096 for (dsn_all_lasthop = TRUE, addr = first_addr;
2097 address_count < max_rcpt && addr != NULL;
2099 if ((addr->dsn_flags & rf_dsnlasthop) != 1)
2101 dsn_all_lasthop = FALSE;
2105 /* Add any DSN flags to the mail command */
2107 if (smtp_use_dsn && !dsn_all_lasthop)
2109 if (dsn_ret == dsn_ret_hdrs)
2111 Ustrcpy(p, " RET=HDRS"); p += 9;
2113 else if (dsn_ret == dsn_ret_full)
2115 Ustrcpy(p, " RET=FULL"); p += 9;
2117 if (dsn_envid != NULL)
2119 string_format(p, sizeof(buffer) - (p-buffer), " ENVID=%s", dsn_envid);
2124 /* If an authenticated_sender override has been specified for this transport
2125 instance, expand it. If the expansion is forced to fail, and there was already
2126 an authenticated_sender for this message, the original value will be used.
2127 Other expansion failures are serious. An empty result is ignored, but there is
2128 otherwise no check - this feature is expected to be used with LMTP and other
2129 cases where non-standard addresses (e.g. without domains) might be required. */
2131 if (smtp_mail_auth_str(p, sizeof(buffer) - (p-buffer), addrlist, ob))
2137 /* From here until we send the DATA command, we can make use of PIPELINING
2138 if the server host supports it. The code has to be able to check the responses
2139 at any point, for when the buffer fills up, so we write it totally generally.
2140 When PIPELINING is off, each command written reports that it has flushed the
2143 pending_MAIL = TRUE; /* The block starts with MAIL */
2146 uschar * s = return_path;
2148 uschar * errstr = NULL;
2150 /* If we must downconvert, do the from-address here. Remember we had to
2151 for the to-addresses (done below), and also (ugly) for re-doing when building
2152 the delivery log line. */
2154 if ( addrlist->prop.utf8_msg
2155 && (addrlist->prop.utf8_downcvt || !(peer_offered & PEER_OFFERED_UTF8))
2158 if (s = string_address_utf8_to_alabel(return_path, &errstr), errstr)
2160 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE);
2164 setflag(addrlist, af_utf8_downcvt);
2168 rc = smtp_write_command(&outblock, smtp_use_pipelining,
2169 "MAIL FROM:<%s>%s\r\n", s, buffer);
2172 mail_command = string_copy(big_buffer); /* Save for later error message */
2176 case -1: /* Transmission error */
2179 case +1: /* Block was sent */
2180 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2181 ob->command_timeout))
2183 if (errno == 0 && buffer[0] == '4')
2185 errno = ERRNO_MAIL4XX;
2186 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2188 goto RESPONSE_FAILED;
2190 pending_MAIL = FALSE;
2194 /* Pass over all the relevant recipient addresses for this host, which are the
2195 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
2196 several before we have to read the responses for those seen so far. This
2197 checking is done by a subroutine because it also needs to be done at the end.
2198 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
2199 the next one if not all are sent.
2201 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
2202 last address because we want to abort if any recipients have any kind of
2203 problem, temporary or permanent. We know that all recipient addresses will have
2204 the PENDING_DEFER status, because only one attempt is ever made, and we know
2205 that max_rcpt will be large, so all addresses will be done at once. */
2207 for (addr = first_addr;
2208 addr && address_count < max_rcpt;
2215 addr->dsn_aware = smtp_use_dsn ? dsn_support_yes : dsn_support_no;
2217 if (addr->transport_return != PENDING_DEFER) continue;
2220 no_flush = smtp_use_pipelining && (!mua_wrapper || addr->next);
2222 /* Add any DSN flags to the rcpt command and add to the sent string */
2227 if (smtp_use_dsn && !(addr->dsn_flags & rf_dsnlasthop))
2229 if ((addr->dsn_flags & rf_dsnflags) != 0)
2233 Ustrcpy(p, " NOTIFY=");
2235 for (i = 0; i < 4; i++)
2236 if ((addr->dsn_flags & rf_list[i]) != 0)
2238 if (!first) *p++ = ',';
2240 Ustrcpy(p, rf_names[i]);
2245 if (addr->dsn_orcpt)
2247 string_format(p, sizeof(buffer) - (p-buffer), " ORCPT=%s",
2253 /* Now send the RCPT command, and process outstanding responses when
2254 necessary. After a timeout on RCPT, we just end the function, leaving the
2255 yield as OK, because this error can often mean that there is a problem with
2256 just one address, so we don't want to delay the host. */
2258 rcpt_addr = transport_rcpt_address(addr, tblock->rcpt_include_affixes);
2262 uschar * dummy_errstr;
2263 if ( testflag(addrlist, af_utf8_downcvt)
2264 && (rcpt_addr = string_address_utf8_to_alabel(rcpt_addr, &dummy_errstr),
2268 errno = ERRNO_EXPANDFAIL;
2274 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s%s\r\n",
2275 rcpt_addr, igquotstr, buffer);
2277 if (count < 0) goto SEND_FAILED;
2280 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
2281 &sync_addr, host, count, ob->address_retry_include_sender,
2282 pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
2285 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2286 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2289 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2290 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2291 case 0: /* No 2xx or 5xx, but no probs */
2294 case -1: goto END_OFF; /* Timeout on RCPT */
2295 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
2297 pending_MAIL = FALSE; /* Dealt with MAIL */
2299 } /* Loop for next address */
2301 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
2302 permanently or temporarily. We should have flushed and synced after the last
2307 address_item *badaddr;
2308 for (badaddr = first_addr; badaddr; badaddr = badaddr->next)
2309 if (badaddr->transport_return != PENDING_OK)
2311 /*XXX could we find a better errno than 0 here? */
2312 set_errno_nohost(addrlist, 0, badaddr->message, FAIL,
2313 testflag(badaddr, af_pass_message));
2319 /* If ok is TRUE, we know we have got at least one good recipient, and must now
2320 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
2321 have a good recipient buffered up if we are pipelining. We don't want to waste
2322 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
2323 are pipelining. The responses are all handled by sync_responses(). */
2325 if (ok || (smtp_use_pipelining && !mua_wrapper))
2327 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
2328 if (count < 0) goto SEND_FAILED;
2329 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
2330 host, count, ob->address_retry_include_sender, pending_MAIL,
2331 ok? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
2333 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2334 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2337 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2338 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2339 case 0: break; /* No 2xx or 5xx, but no probs */
2341 case -1: goto END_OFF; /* Timeout on RCPT */
2342 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2346 /* Save the first address of the next batch. */
2350 /* If there were no good recipients (but otherwise there have been no
2351 problems), just set ok TRUE, since we have handled address-specific errors
2352 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
2353 for handling the SMTP dot-handling protocol, flagging to apply to headers as
2354 well as body. Set the appropriate timeout value to be used for each chunk.
2355 (Haven't been able to make it work using select() for writing yet.) */
2361 int options = topt_use_crlf | topt_escape_headers
2362 | (tblock->body_only ? topt_no_headers : 0)
2363 | (tblock->headers_only ? topt_no_body : 0)
2364 | (tblock->return_path_add ? topt_add_return_path : 0)
2365 | (tblock->delivery_date_add ?topt_add_delivery_date :0)
2366 | (tblock->envelope_to_add ? topt_add_envelope_to : 0);
2367 uschar * str_spot, * str_repl;
2369 if (peer_offered & PEER_OFFERED_CHUNKING)
2371 options |= topt_use_bdat;
2372 str_spot = str_repl = NULL;
2376 options |= topt_end_dot;
2377 str_spot = US"."; str_repl = US"..";
2380 sigalrm_seen = FALSE;
2381 transport_write_timeout = ob->data_timeout;
2382 smtp_command = US"sending data block"; /* For error messages */
2383 DEBUG(D_transport|D_v)
2384 debug_printf(" SMTP>> writing message %s\n",
2385 peer_offered & PEER_OFFERED_CHUNKING
2386 ? "using CHUNKING" : "and terminating \".\"");
2387 transport_count = 0;
2389 #ifndef DISABLE_DKIM
2390 ok = dkim_transport_write_message(addrlist, inblock.sock,
2392 tblock->add_headers, tblock->remove_headers,
2393 str_spot, str_repl, /* Escaping strings */
2394 tblock->rewrite_rules, tblock->rewrite_existflags,
2398 ok = transport_write_message(addrlist, inblock.sock,
2400 0, /* No size limit */
2401 tblock->add_headers, tblock->remove_headers,
2402 str_spot, str_repl, /* Escaping strings */
2403 tblock->rewrite_rules, tblock->rewrite_existflags);
2406 /* transport_write_message() uses write() because it is called from other
2407 places to write to non-sockets. This means that under some OS (e.g. Solaris)
2408 it can exit with "Broken pipe" as its error. This really means that the
2409 socket got closed at the far end. */
2411 transport_write_timeout = 0; /* for subsequent transports */
2413 /* Failure can either be some kind of I/O disaster (including timeout),
2414 or the failure of a transport filter or the expansion of added headers. */
2418 buffer[0] = 0; /* There hasn't been a response */
2419 goto RESPONSE_FAILED;
2422 /* We used to send the terminating "." explicitly here, but because of
2423 buffering effects at both ends of TCP/IP connections, you don't gain
2424 anything by keeping it separate, so it might as well go in the final
2425 data buffer for efficiency. This is now done by setting the topt_end_dot
2428 smtp_command = US"end of data";
2430 #ifndef DISABLE_PRDR
2431 /* For PRDR we optionally get a partial-responses warning
2432 * followed by the individual responses, before going on with
2433 * the overall response. If we don't get the warning then deal
2434 * with per non-PRDR. */
2437 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '3',
2439 if (!ok && errno == 0)
2442 case '2': prdr_active = FALSE;
2445 case '4': errno = ERRNO_DATA4XX;
2446 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2453 /* For non-PRDR SMTP, we now read a single response that applies to the
2454 whole message. If it is OK, then all the addresses have been delivered. */
2458 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2460 if (!ok && errno == 0 && buffer[0] == '4')
2462 errno = ERRNO_DATA4XX;
2463 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2467 /* For LMTP, we get back a response for every RCPT command that we sent;
2468 some may be accepted and some rejected. For those that get a response, their
2469 status is fixed; any that are accepted have been handed over, even if later
2470 responses crash - at least, that's how I read RFC 2033.
2472 If all went well, mark the recipient addresses as completed, record which
2473 host/IPaddress they were delivered to, and cut out RSET when sending another
2474 message down the same channel. Write the completed addresses to the journal
2475 now so that they are recorded in case there is a crash of hardware or
2476 software before the spool gets updated. Also record the final SMTP
2477 confirmation if needed (for SMTP only). */
2482 int delivery_time = (int)(time(NULL) - start_delivery_time);
2484 uschar *conf = NULL;
2487 /* Set up confirmation if needed - applies only to SMTP */
2490 #ifdef DISABLE_EVENT
2491 LOGGING(smtp_confirmation) &&
2496 const uschar *s = string_printing(buffer);
2497 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
2498 conf = (s == buffer)? (uschar *)string_copy(s) : US s;
2501 /* Process all transported addresses - for LMTP or PRDR, read a status for
2504 for (addr = addrlist; addr != first_addr; addr = addr->next)
2506 if (addr->transport_return != PENDING_OK) continue;
2508 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
2509 remaining addresses. Otherwise, it's a return code for just the one
2510 address. For temporary errors, add a retry item for the address so that
2511 it doesn't get tried again too soon. */
2513 #ifndef DISABLE_PRDR
2514 if (lmtp || prdr_active)
2519 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2522 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
2523 addr->message = string_sprintf(
2524 #ifndef DISABLE_PRDR
2525 "%s error after %s: %s", prdr_active ? "PRDR":"LMTP",
2527 "LMTP error after %s: %s",
2529 big_buffer, string_printing(buffer));
2530 setflag(addr, af_pass_message); /* Allow message to go to user */
2531 if (buffer[0] == '5')
2532 addr->transport_return = FAIL;
2535 errno = ERRNO_DATA4XX;
2536 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2537 addr->transport_return = DEFER;
2538 #ifndef DISABLE_PRDR
2541 retry_add_item(addr, addr->address_retry_key, 0);
2545 completed_address = TRUE; /* NOW we can set this flag */
2546 if (LOGGING(smtp_confirmation))
2548 const uschar *s = string_printing(buffer);
2549 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
2550 conf = (s == buffer)? (uschar *)string_copy(s) : US s;
2554 /* SMTP, or success return from LMTP for this address. Pass back the
2555 actual host that was used. */
2557 addr->transport_return = OK;
2558 addr->more_errno = delivery_time;
2559 addr->host_used = host;
2560 addr->special_action = flag;
2561 addr->message = conf;
2562 #ifndef DISABLE_PRDR
2563 if (prdr_active) addr->flags |= af_prdr_used;
2567 #ifndef DISABLE_PRDR
2571 /* Update the journal. For homonymic addresses, use the base address plus
2572 the transport name. See lots of comments in deliver.c about the reasons
2573 for the complications when homonyms are involved. Just carry on after
2574 write error, as it may prove possible to update the spool file later. */
2576 if (testflag(addr, af_homonym))
2577 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2579 sprintf(CS buffer, "%.500s\n", addr->unique);
2581 DEBUG(D_deliver) debug_printf("journalling %s\n", buffer);
2582 len = Ustrlen(CS buffer);
2583 if (write(journal_fd, buffer, len) != len)
2584 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2585 "%s: %s", buffer, strerror(errno));
2589 #ifndef DISABLE_PRDR
2592 /* PRDR - get the final, overall response. For any non-success
2593 upgrade all the address statuses. */
2594 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2598 if(errno == 0 && buffer[0] == '4')
2600 errno = ERRNO_DATA4XX;
2601 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2603 for (addr = addrlist; addr != first_addr; addr = addr->next)
2604 if (buffer[0] == '5' || addr->transport_return == OK)
2605 addr->transport_return = PENDING_OK; /* allow set_errno action */
2606 goto RESPONSE_FAILED;
2609 /* Update the journal, or setup retry. */
2610 for (addr = addrlist; addr != first_addr; addr = addr->next)
2611 if (addr->transport_return == OK)
2613 if (testflag(addr, af_homonym))
2614 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2616 sprintf(CS buffer, "%.500s\n", addr->unique);
2618 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s\n", buffer);
2619 len = Ustrlen(CS buffer);
2620 if (write(journal_fd, buffer, len) != len)
2621 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2622 "%s: %s", buffer, strerror(errno));
2624 else if (addr->transport_return == DEFER)
2625 retry_add_item(addr, addr->address_retry_key, -2);
2629 /* Ensure the journal file is pushed out to disk. */
2631 if (EXIMfsync(journal_fd) < 0)
2632 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
2638 /* Handle general (not specific to one address) failures here. The value of ok
2639 is used to skip over this code on the falling through case. A timeout causes a
2640 deferral. Other errors may defer or fail according to the response code, and
2641 may set up a special errno value, e.g. after connection chopped, which is
2642 assumed if errno == 0 and there is no text in the buffer. If control reaches
2643 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
2644 the problem is not related to this specific message. */
2649 uschar * set_message;
2655 send_quit = check_response(host, &save_errno, addrlist->more_errno,
2656 buffer, &code, &message, &pass_message);
2664 message = US string_sprintf("send() to %s [%s] failed: %s",
2665 host->name, host->address, strerror(save_errno));
2670 /* This label is jumped to directly when a TLS negotiation has failed,
2671 or was not done for a host for which it is required. Values will be set
2672 in message and save_errno, and setting_up will always be true. Treat as
2673 a temporary error. */
2680 /* If the failure happened while setting up the call, see if the failure was
2681 a 5xx response (this will either be on connection, or following HELO - a 5xx
2682 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
2683 never going to accept them. For other errors during setting up (timeouts or
2684 whatever), defer all addresses, and yield DEFER, so that the host is not
2685 tried again for a while. */
2688 ok = FALSE; /* For when reached by GOTO */
2689 set_message = message;
2696 yield = set_rc = DEFER;
2699 /* We want to handle timeouts after MAIL or "." and loss of connection after
2700 "." specially. They can indicate a problem with the sender address or with
2701 the contents of the message rather than a real error on the connection. These
2702 cases are treated in the same way as a 4xx response. This next bit of code
2703 does the classification. */
2712 case ERRNO_UTF8_FWD:
2719 message_error = TRUE;
2723 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
2724 Ustrncmp(smtp_command,"end ",4) == 0;
2727 case ERRNO_SMTPCLOSED:
2728 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
2732 message_error = FALSE;
2736 /* Handle the cases that are treated as message errors. These are:
2738 (a) negative response or timeout after MAIL
2739 (b) negative response after DATA
2740 (c) negative response or timeout or dropped connection after "."
2741 (d) utf8 support required and not offered
2743 It won't be a negative response or timeout after RCPT, as that is dealt
2744 with separately above. The action in all cases is to set an appropriate
2745 error code for all the addresses, but to leave yield set to OK because the
2746 host itself has not failed. Of course, it might in practice have failed
2747 when we've had a timeout, but if so, we'll discover that at the next
2748 delivery attempt. For a temporary error, set the message_defer flag, and
2749 write to the logs for information if this is not the last host. The error
2750 for the last host will be logged as part of the address's log line. */
2754 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
2756 /* If there's an errno, the message contains just the identity of
2761 else /* Anything other than 5 is treated as temporary */
2765 message = US string_sprintf("%s: %s", message, strerror(save_errno));
2766 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
2767 msglog_line(host, message);
2768 *message_defer = TRUE;
2772 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
2773 ".", or some other transportation error. We defer all addresses and yield
2774 DEFER, except for the case of failed add_headers expansion, or a transport
2775 filter failure, when the yield should be ERROR, to stop it trying other
2781 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
2782 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
2786 set_errno(addrlist, save_errno, set_message, set_rc, pass_message, host
2787 #ifdef EXPERIMENTAL_DSN_INFO
2788 , smtp_greeting, helo_response
2794 /* If all has gone well, send_quit will be set TRUE, implying we can end the
2795 SMTP session tidily. However, if there were too many addresses to send in one
2796 message (indicated by first_addr being non-NULL) we want to carry on with the
2797 rest of them. Also, it is desirable to send more than one message down the SMTP
2798 connection if there are several waiting, provided we haven't already sent so
2799 many as to hit the configured limit. The function transport_check_waiting looks
2800 for a waiting message and returns its id. Then transport_pass_socket tries to
2801 set up a continued delivery by passing the socket on to another process. The
2802 variable send_rset is FALSE if a message has just been successfully transfered.
2804 If we are already sending down a continued channel, there may be further
2805 addresses not yet delivered that are aimed at the same host, but which have not
2806 been passed in this run of the transport. In this case, continue_more will be
2807 true, and all we should do is send RSET if necessary, and return, leaving the
2810 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
2811 do not want to continue with other messages down the same channel, because that
2812 can lead to looping between two or more messages, all with the same,
2813 temporarily failing address(es). [The retry information isn't updated yet, so
2814 new processes keep on trying.] We probably also don't want to try more of this
2815 message's addresses either.
2817 If we have started a TLS session, we have to end it before passing the
2818 connection to a new process. However, not all servers can handle this (Exim
2819 can), so we do not pass such a connection on if the host matches
2820 hosts_nopass_tls. */
2823 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
2824 "yield=%d first_address is %sNULL\n", ok, send_quit, send_rset,
2825 continue_more, yield, (first_addr == NULL)? "":"not ");
2827 if (completed_address && ok && send_quit)
2830 smtp_compare_t t_compare;
2832 t_compare.tblock = tblock;
2833 t_compare.current_sender_address = sender_address;
2835 if ( first_addr != NULL
2837 || ( ( tls_out.active < 0
2838 || verify_check_given_host(&ob->hosts_nopass_tls, host) != OK
2841 transport_check_waiting(tblock->name, host->name,
2842 tblock->connection_max_messages, new_message_id, &more,
2843 (oicf)smtp_are_same_identities, (void*)&t_compare)
2851 if (! (ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
2853 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
2854 host->address, strerror(save_errno));
2857 else if (! (ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2858 ob->command_timeout)))
2861 send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
2865 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
2866 host->name, host->address, msg);
2871 /* Either RSET was not needed, or it succeeded */
2875 if (first_addr != NULL) /* More addresses still to be sent */
2876 { /* in this run of the transport */
2877 continue_sequence++; /* Causes * in logging */
2880 if (continue_more) return yield; /* More addresses for another run */
2882 /* Pass the socket to a new Exim process. Before doing so, we must shut
2883 down TLS. Not all MTAs allow for the continuation of the SMTP session
2884 when TLS is shut down. We test for this by sending a new EHLO. If we
2885 don't get a good response, we don't attempt to pass the socket on. */
2888 if (tls_out.active >= 0)
2890 tls_close(FALSE, TRUE);
2894 ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
2895 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2896 ob->command_timeout);
2900 /* If the socket is successfully passed, we musn't send QUIT (or
2901 indeed anything!) from here. */
2903 /*XXX DSN_INFO: assume likely to do new HELO; but for greet we'll want to
2904 propagate it from the initial
2906 if (ok && transport_pass_socket(tblock->name, host->name, host->address,
2907 new_message_id, inblock.sock))
2913 /* If RSET failed and there are addresses left, they get deferred. */
2915 else set_errno(first_addr, errno, msg, DEFER, FALSE, host
2916 #ifdef EXPERIMENTAL_DSN_INFO
2917 , smtp_greeting, helo_response
2923 /* End off tidily with QUIT unless the connection has died or the socket has
2924 been passed to another process. There has been discussion on the net about what
2925 to do after sending QUIT. The wording of the RFC suggests that it is necessary
2926 to wait for a response, but on the other hand, there isn't anything one can do
2927 with an error response, other than log it. Exim used to do that. However,
2928 further discussion suggested that it is positively advantageous not to wait for
2929 the response, but to close the session immediately. This is supposed to move
2930 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
2931 load from the server. (Hosts that are both servers and clients may not see much
2932 difference, of course.) Further discussion indicated that this was safe to do
2933 on Unix systems which have decent implementations of TCP/IP that leave the
2934 connection around for a while (TIME_WAIT) after the application has gone away.
2935 This enables the response sent by the server to be properly ACKed rather than
2936 timed out, as can happen on broken TCP/IP implementations on other OS.
2938 This change is being made on 31-Jul-98. After over a year of trouble-free
2939 operation, the old commented-out code was removed on 17-Sep-99. */
2942 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2947 tls_close(FALSE, TRUE);
2950 /* Close the socket, and return the appropriate value, first setting
2951 works because the NULL setting is passed back to the calling process, and
2952 remote_max_parallel is forced to 1 when delivering over an existing connection,
2954 If all went well and continue_more is set, we shouldn't actually get here if
2955 there are further addresses, as the return above will be taken. However,
2956 writing RSET might have failed, or there may be other addresses whose hosts are
2957 specified in the transports, and therefore not visible at top level, in which
2958 case continue_more won't get set. */
2960 HDEBUG(D_transport|D_acl|D_v) debug_printf(" SMTP(close)>>\n");
2961 (void)close(inblock.sock);
2963 #ifndef DISABLE_EVENT
2964 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
2967 continue_transport = NULL;
2968 continue_hostname = NULL;
2975 /*************************************************
2976 * Closedown entry point *
2977 *************************************************/
2979 /* This function is called when exim is passed an open smtp channel
2980 from another incarnation, but the message which it has been asked
2981 to deliver no longer exists. The channel is on stdin.
2983 We might do fancy things like looking for another message to send down
2984 the channel, but if the one we sought has gone, it has probably been
2985 delivered by some other process that itself will seek further messages,
2986 so just close down our connection.
2988 Argument: pointer to the transport instance block
2993 smtp_transport_closedown(transport_instance *tblock)
2995 smtp_transport_options_block *ob =
2996 (smtp_transport_options_block *)(tblock->options_block);
2997 smtp_inblock inblock;
2998 smtp_outblock outblock;
3000 uschar inbuffer[4096];
3001 uschar outbuffer[16];
3003 inblock.sock = fileno(stdin);
3004 inblock.buffer = inbuffer;
3005 inblock.buffersize = sizeof(inbuffer);
3006 inblock.ptr = inbuffer;
3007 inblock.ptrend = inbuffer;
3009 outblock.sock = inblock.sock;
3010 outblock.buffersize = sizeof(outbuffer);
3011 outblock.buffer = outbuffer;
3012 outblock.ptr = outbuffer;
3013 outblock.cmd_count = 0;
3014 outblock.authenticating = FALSE;
3016 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
3017 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
3018 ob->command_timeout);
3019 (void)close(inblock.sock);
3024 /*************************************************
3025 * Prepare addresses for delivery *
3026 *************************************************/
3028 /* This function is called to flush out error settings from previous delivery
3029 attempts to other hosts. It also records whether we got here via an MX record
3030 or not in the more_errno field of the address. We are interested only in
3031 addresses that are still marked DEFER - others may have got delivered to a
3032 previously considered IP address. Set their status to PENDING_DEFER to indicate
3033 which ones are relevant this time.
3036 addrlist the list of addresses
3037 host the host we are delivering to
3039 Returns: the first address for this delivery
3042 static address_item *
3043 prepare_addresses(address_item *addrlist, host_item *host)
3045 address_item *first_addr = NULL;
3047 for (addr = addrlist; addr != NULL; addr = addr->next)
3048 if (addr->transport_return == DEFER)
3050 if (first_addr == NULL) first_addr = addr;
3051 addr->transport_return = PENDING_DEFER;
3052 addr->basic_errno = 0;
3053 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
3054 addr->message = NULL;
3056 addr->cipher = NULL;
3057 addr->ourcert = NULL;
3058 addr->peercert = NULL;
3059 addr->peerdn = NULL;
3060 addr->ocsp = OCSP_NOT_REQ;
3062 #ifdef EXPERIMENTAL_DSN_INFO
3063 addr->smtp_greeting = NULL;
3064 addr->helo_response = NULL;
3072 /*************************************************
3073 * Main entry point *
3074 *************************************************/
3076 /* See local README for interface details. As this is a remote transport, it is
3077 given a chain of addresses to be delivered in one connection, if possible. It
3078 always returns TRUE, indicating that each address has its own independent
3079 status set, except if there is a setting up problem, in which case it returns
3083 smtp_transport_entry(
3084 transport_instance *tblock, /* data for this instantiation */
3085 address_item *addrlist) /* addresses we are working on */
3089 int hosts_defer = 0;
3091 int hosts_looked_up = 0;
3092 int hosts_retry = 0;
3093 int hosts_serial = 0;
3094 int hosts_total = 0;
3095 int total_hosts_tried = 0;
3097 BOOL expired = TRUE;
3098 BOOL continuing = continue_hostname != NULL;
3099 uschar *expanded_hosts = NULL;
3101 uschar *tid = string_sprintf("%s transport", tblock->name);
3102 smtp_transport_options_block *ob =
3103 (smtp_transport_options_block *)(tblock->options_block);
3104 host_item *hostlist = addrlist->host_list;
3105 host_item *host = NULL;
3109 debug_printf("%s transport entered\n", tblock->name);
3110 for (addr = addrlist; addr != NULL; addr = addr->next)
3111 debug_printf(" %s\n", addr->address);
3112 if (continuing) debug_printf("already connected to %s [%s]\n",
3113 continue_hostname, continue_host_address);
3116 /* Set the flag requesting that these hosts be added to the waiting
3117 database if the delivery fails temporarily or if we are running with
3118 queue_smtp or a 2-stage queue run. This gets unset for certain
3119 kinds of error, typically those that are specific to the message. */
3121 update_waiting = TRUE;
3123 /* If a host list is not defined for the addresses - they must all have the
3124 same one in order to be passed to a single transport - or if the transport has
3125 a host list with hosts_override set, use the host list supplied with the
3126 transport. It is an error for this not to exist. */
3128 if (hostlist == NULL || (ob->hosts_override && ob->hosts != NULL))
3130 if (ob->hosts == NULL)
3132 addrlist->message = string_sprintf("%s transport called with no hosts set",
3134 addrlist->transport_return = PANIC;
3135 return FALSE; /* Only top address has status */
3138 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
3141 /* If the transport's host list contains no '$' characters, and we are not
3142 randomizing, it is fixed and therefore a chain of hosts can be built once
3143 and for all, and remembered for subsequent use by other calls to this
3144 transport. If, on the other hand, the host list does contain '$', or we are
3145 randomizing its order, we have to rebuild it each time. In the fixed case,
3146 as the hosts string will never be used again, it doesn't matter that we
3147 replace all the : characters with zeros. */
3149 if (ob->hostlist == NULL)
3151 uschar *s = ob->hosts;
3153 if (Ustrchr(s, '$') != NULL)
3155 if (!(expanded_hosts = expand_string(s)))
3157 addrlist->message = string_sprintf("failed to expand list of hosts "
3158 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
3159 addrlist->transport_return = search_find_defer? DEFER : PANIC;
3160 return FALSE; /* Only top address has status */
3162 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
3163 "\"%s\"\n", s, expanded_hosts);
3167 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
3169 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
3171 /* Check that the expansion yielded something useful. */
3172 if (hostlist == NULL)
3175 string_sprintf("%s transport has empty hosts setting", tblock->name);
3176 addrlist->transport_return = PANIC;
3177 return FALSE; /* Only top address has status */
3180 /* If there was no expansion of hosts, save the host list for
3183 if (!expanded_hosts) ob->hostlist = hostlist;
3186 /* This is not the first time this transport has been run in this delivery;
3187 the host list was built previously. */
3190 hostlist = ob->hostlist;
3193 /* The host list was supplied with the address. If hosts_randomize is set, we
3194 must sort it into a random order if it did not come from MX records and has not
3195 already been randomized (but don't bother if continuing down an existing
3198 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continuing)
3200 host_item *newlist = NULL;
3201 while (hostlist != NULL)
3203 host_item *h = hostlist;
3204 hostlist = hostlist->next;
3206 h->sort_key = random_number(100);
3208 if (newlist == NULL)
3213 else if (h->sort_key < newlist->sort_key)
3220 host_item *hh = newlist;
3221 while (hh->next != NULL)
3223 if (h->sort_key < hh->next->sort_key) break;
3231 hostlist = addrlist->host_list = newlist;
3234 /* Sort out the default port. */
3236 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
3238 /* For each host-plus-IP-address on the list:
3240 . If this is a continued delivery and the host isn't the one with the
3241 current connection, skip.
3243 . If the status is unusable (i.e. previously failed or retry checked), skip.
3245 . If no IP address set, get the address, either by turning the name into
3246 an address, calling gethostbyname if gethostbyname is on, or by calling
3247 the DNS. The DNS may yield multiple addresses, in which case insert the
3248 extra ones into the list.
3250 . Get the retry data if not previously obtained for this address and set the
3251 field which remembers the state of this address. Skip if the retry time is
3252 not reached. If not, remember whether retry data was found. The retry string
3253 contains both the name and the IP address.
3255 . Scan the list of addresses and mark those whose status is DEFER as
3256 PENDING_DEFER. These are the only ones that will be processed in this cycle
3259 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
3260 Some addresses may be successfully delivered, others may fail, and yet
3261 others may get temporary errors and so get marked DEFER.
3263 . The return from the delivery attempt is OK if a connection was made and a
3264 valid SMTP dialogue was completed. Otherwise it is DEFER.
3266 . If OK, add a "remove" retry item for this host/IPaddress, if any.
3268 . If fail to connect, or other defer state, add a retry item.
3270 . If there are any addresses whose status is still DEFER, carry on to the
3271 next host/IPaddress, unless we have tried the number of hosts given
3272 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
3273 there is some fancy logic for hosts_max_try that means its limit can be
3274 overstepped in some circumstances.
3276 If we get to the end of the list, all hosts have deferred at least one address,
3277 or not reached their retry times. If delay_after_cutoff is unset, it requests a
3278 delivery attempt to those hosts whose last try was before the arrival time of
3279 the current message. To cope with this, we have to go round the loop a second
3280 time. After that, set the status and error data for any addresses that haven't
3281 had it set already. */
3283 for (cutoff_retry = 0; expired &&
3284 cutoff_retry < ((ob->delay_after_cutoff)? 1 : 2);
3287 host_item *nexthost = NULL;
3288 int unexpired_hosts_tried = 0;
3290 for (host = hostlist;
3292 unexpired_hosts_tried < ob->hosts_max_try &&
3293 total_hosts_tried < ob->hosts_max_try_hardlimit;
3299 BOOL serialized = FALSE;
3300 BOOL host_is_expired = FALSE;
3301 BOOL message_defer = FALSE;
3302 BOOL some_deferred = FALSE;
3303 address_item *first_addr = NULL;
3304 uschar *interface = NULL;
3305 uschar *retry_host_key = NULL;
3306 uschar *retry_message_key = NULL;
3307 uschar *serialize_key = NULL;
3309 /* Default next host is next host. :-) But this can vary if the
3310 hosts_max_try limit is hit (see below). It may also be reset if a host
3311 address is looked up here (in case the host was multihomed). */
3313 nexthost = host->next;
3315 /* If the address hasn't yet been obtained from the host name, look it up
3316 now, unless the host is already marked as unusable. If it is marked as
3317 unusable, it means that the router was unable to find its IP address (in
3318 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
3319 the lookup failed last time. We don't get this far if *all* MX records
3320 point to non-existent hosts; that is treated as a hard error.
3322 We can just skip this host entirely. When the hosts came from the router,
3323 the address will timeout based on the other host(s); when the address is
3324 looked up below, there is an explicit retry record added.
3326 Note that we mustn't skip unusable hosts if the address is not unset; they
3327 may be needed as expired hosts on the 2nd time round the cutoff loop. */
3329 if (host->address == NULL)
3331 int new_port, flags;
3334 if (host->status >= hstatus_unusable)
3336 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
3341 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
3343 /* The host name is permitted to have an attached port. Find it, and
3344 strip it from the name. Just remember it for now. */
3346 new_port = host_item_get_port(host);
3348 /* Count hosts looked up */
3352 /* Find by name if so configured, or if it's an IP address. We don't
3353 just copy the IP address, because we need the test-for-local to happen. */
3355 flags = HOST_FIND_BY_A;
3356 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
3357 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
3359 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
3360 rc = host_find_byname(host, NULL, flags, NULL, TRUE);
3362 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
3363 &ob->dnssec, /* domains for request/require */
3366 /* Update the host (and any additional blocks, resulting from
3367 multihoming) with a host-specific port, if any. */
3369 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
3371 /* Failure to find the host at this time (usually DNS temporary failure)
3372 is really a kind of routing failure rather than a transport failure.
3373 Therefore we add a retry item of the routing kind, not to stop us trying
3374 to look this name up here again, but to ensure the address gets timed
3375 out if the failures go on long enough. A complete failure at this point
3376 commonly points to a configuration error, but the best action is still
3377 to carry on for the next host. */
3379 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
3381 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
3383 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
3384 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
3385 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
3386 host->status = hstatus_unusable;
3388 for (addr = addrlist; addr != NULL; addr = addr->next)
3390 if (addr->transport_return != DEFER) continue;
3391 addr->basic_errno = ERRNO_UNKNOWNHOST;
3393 string_sprintf("failed to lookup IP address for %s", host->name);
3398 /* If the host is actually the local host, we may have a problem, or
3399 there may be some cunning configuration going on. In the problem case,
3400 log things and give up. The default transport status is already DEFER. */
3402 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
3404 for (addr = addrlist; addr != NULL; addr = addr->next)
3406 addr->basic_errno = 0;
3407 addr->message = string_sprintf("%s transport found host %s to be "
3408 "local", tblock->name, host->name);
3412 } /* End of block for IP address lookup */
3414 /* If this is a continued delivery, we are interested only in the host
3415 which matches the name of the existing open channel. The check is put
3416 here after the local host lookup, in case the name gets expanded as a
3417 result of the lookup. Set expired FALSE, to save the outer loop executing
3420 if (continuing && (Ustrcmp(continue_hostname, host->name) != 0 ||
3421 Ustrcmp(continue_host_address, host->address) != 0))
3424 continue; /* With next host */
3427 /* Reset the default next host in case a multihomed host whose addresses
3428 are not looked up till just above added to the host list. */
3430 nexthost = host->next;
3432 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
3433 domain is in queue_smtp_domains, we don't actually want to attempt any
3434 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
3435 there is a lookup defer in queue_smtp_domains, proceed as if the domain
3436 were not in it. We don't want to hold up all SMTP deliveries! Except when
3437 doing a two-stage queue run, don't do this if forcing. */
3439 if ((!deliver_force || queue_2stage) && (queue_smtp ||
3440 match_isinlist(addrlist->domain,
3441 (const uschar **)&queue_smtp_domains, 0,
3442 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
3445 for (addr = addrlist; addr != NULL; addr = addr->next)
3447 if (addr->transport_return != DEFER) continue;
3448 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
3450 continue; /* With next host */
3453 /* Count hosts being considered - purely for an intelligent comment
3454 if none are usable. */
3458 /* Set $host and $host address now in case they are needed for the
3459 interface expansion or the serialize_hosts check; they remain set if an
3460 actual delivery happens. */
3462 deliver_host = host->name;
3463 deliver_host_address = host->address;
3464 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
3465 : host->dnssec == DS_NO ? US"no"
3468 /* Set up a string for adding to the retry key if the port number is not
3469 the standard SMTP port. A host may have its own port setting that overrides
3472 pistring = string_sprintf(":%d", (host->port == PORT_NONE)?
3474 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
3476 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
3477 string is set, even if constant (as different transports can have different
3478 constant settings), we must add it to the key that is used for retries,
3479 because connections to the same host from a different interface should be
3480 treated separately. */
3482 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET : AF_INET6;
3483 if ((rs = ob->interface) && *rs)
3485 if (!smtp_get_interface(rs, host_af, addrlist, &interface, tid))
3487 pistring = string_sprintf("%s/%s", pistring, interface);
3490 /* The first time round the outer loop, check the status of the host by
3491 inspecting the retry data. The second time round, we are interested only
3492 in expired hosts that haven't been tried since this message arrived. */
3494 if (cutoff_retry == 0)
3497 /* Ensure the status of the address is set by checking retry data if
3498 necessary. There may be host-specific retry data (applicable to all
3499 messages) and also data for retries of a specific message at this host.
3500 If either of these retry records are actually read, the keys used are
3501 returned to save recomputing them later. */
3503 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3504 US"retry_include_ip_address", ob->retry_include_ip_address,
3505 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3506 continue; /* with next host */
3508 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
3509 incl_ip, &retry_host_key, &retry_message_key);
3511 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
3512 (host->address == NULL)? US"" : host->address, pistring,
3513 (host->status == hstatus_usable)? "usable" :
3514 (host->status == hstatus_unusable)? "unusable" :
3515 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
3517 /* Skip this address if not usable at this time, noting if it wasn't
3518 actually expired, both locally and in the address. */
3520 switch (host->status)
3522 case hstatus_unusable:
3524 setflag(addrlist, af_retry_skipped);
3527 case hstatus_unusable_expired:
3530 case hwhy_retry: hosts_retry++; break;
3531 case hwhy_failed: hosts_fail++; break;
3532 case hwhy_deferred: hosts_defer++; break;
3535 /* If there was a retry message key, implying that previously there
3536 was a message-specific defer, we don't want to update the list of
3537 messages waiting for these hosts. */
3539 if (retry_message_key != NULL) update_waiting = FALSE;
3540 continue; /* With the next host or IP address */
3544 /* Second time round the loop: if the address is set but expired, and
3545 the message is newer than the last try, let it through. */
3549 if (host->address == NULL ||
3550 host->status != hstatus_unusable_expired ||
3551 host->last_try > received_time)
3554 debug_printf("trying expired host %s [%s]%s\n",
3555 host->name, host->address, pistring);
3556 host_is_expired = TRUE;
3559 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
3560 it remains TRUE only if all hosts are expired and none are actually tried.
3565 /* If this host is listed as one to which access must be serialized,
3566 see if another Exim process has a connection to it, and if so, skip
3567 this host. If not, update the database to record our connection to it
3568 and remember this for later deletion. Do not do any of this if we are
3569 sending the message down a pre-existing connection. */
3572 verify_check_given_host(&ob->serialize_hosts, host) == OK)
3574 serialize_key = string_sprintf("host-serialize-%s", host->name);
3575 if (!enq_start(serialize_key, 1))
3578 debug_printf("skipping host %s because another Exim process "
3579 "is connected to it\n", host->name);
3586 /* OK, we have an IP address that is not waiting for its retry time to
3587 arrive (it might be expired) OR (second time round the loop) we have an
3588 expired host that hasn't been tried since the message arrived. Have a go
3589 at delivering the message to it. First prepare the addresses by flushing
3590 out the result of previous attempts, and finding the first address that
3591 is still to be delivered. */
3593 first_addr = prepare_addresses(addrlist, host);
3595 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
3596 message_id, host->name, host->address, addrlist->address,
3597 (addrlist->next == NULL)? "" : ", ...");
3599 set_process_info("delivering %s to %s [%s] (%s%s)",
3600 message_id, host->name, host->address, addrlist->address,
3601 (addrlist->next == NULL)? "" : ", ...");
3603 /* This is not for real; don't do the delivery. If there are
3604 any remaining hosts, list them. */
3609 set_errno_nohost(addrlist, 0, NULL, OK, FALSE);
3610 for (addr = addrlist; addr != NULL; addr = addr->next)
3612 addr->host_used = host;
3613 addr->special_action = '*';
3614 addr->message = US"delivery bypassed by -N option";
3618 debug_printf("*** delivery by %s transport bypassed by -N option\n"
3619 "*** host and remaining hosts:\n", tblock->name);
3620 for (host2 = host; host2 != NULL; host2 = host2->next)
3621 debug_printf(" %s [%s]\n", host2->name,
3622 (host2->address == NULL)? US"unset" : host2->address);
3627 /* This is for real. If the host is expired, we don't count it for
3628 hosts_max_retry. This ensures that all hosts must expire before an address
3629 is timed out, unless hosts_max_try_hardlimit (which protects against
3630 lunatic DNS configurations) is reached.
3632 If the host is not expired and we are about to hit the hosts_max_retry
3633 limit, check to see if there is a subsequent hosts with a different MX
3634 value. If so, make that the next host, and don't count this one. This is a
3635 heuristic to make sure that different MXs do get tried. With a normal kind
3636 of retry rule, they would get tried anyway when the earlier hosts were
3637 delayed, but if the domain has a "retry every time" type of rule - as is
3638 often used for the the very large ISPs, that won't happen. */
3643 /* Make a copy of the host if it is local to this invocation
3644 of the transport. */
3648 thost = store_get(sizeof(host_item));
3650 thost->name = string_copy(host->name);
3651 thost->address = string_copy(host->address);
3656 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
3660 debug_printf("hosts_max_try limit reached with this host\n");
3661 for (h = host; h; h = h->next) if (h->mx != host->mx)
3664 unexpired_hosts_tried--;
3665 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
3666 "and will be tried\n");
3671 /* Attempt the delivery. */
3673 total_hosts_tried++;
3674 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
3675 &message_defer, FALSE);
3678 OK => connection made, each address contains its result;
3679 message_defer is set for message-specific defers (when all
3680 recipients are marked defer)
3681 DEFER => there was a non-message-specific delivery problem;
3682 ERROR => there was a problem setting up the arguments for a filter,
3683 or there was a problem with expanding added headers
3686 /* If the result is not OK, there was a non-message-specific problem.
3687 If the result is DEFER, we need to write to the logs saying what happened
3688 for this particular host, except in the case of authentication and TLS
3689 failures, where the log has already been written. If all hosts defer a
3690 general message is written at the end. */
3692 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL &&
3693 first_addr->basic_errno != ERRNO_TLSFAILURE)
3694 write_logs(first_addr, host);
3696 #ifndef DISABLE_EVENT
3698 deferred_event_raise(first_addr, host);
3701 /* If STARTTLS was accepted, but there was a failure in setting up the
3702 TLS session (usually a certificate screwup), and the host is not in
3703 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
3704 TLS forcibly turned off. We have to start from scratch with a new SMTP
3705 connection. That's why the retry is done from here, not from within
3706 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
3707 session, so the in-clear transmission after those errors, if permitted,
3708 happens inside smtp_deliver().] */
3712 && first_addr->basic_errno == ERRNO_TLSFAILURE
3713 && ob->tls_tempfail_tryclear
3714 && verify_check_given_host(&ob->hosts_require_tls, host) != OK
3717 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
3718 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
3719 first_addr = prepare_addresses(addrlist, host);
3720 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
3721 &message_defer, TRUE);
3722 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
3723 write_logs(first_addr, host);
3724 # ifndef DISABLE_EVENT
3726 deferred_event_raise(first_addr, host);
3729 #endif /*SUPPORT_TLS*/
3732 /* Delivery attempt finished */
3734 rs = (rc == OK)? US"OK" : (rc == DEFER)? US"DEFER" : (rc == ERROR)?
3737 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
3738 message_id, host->name, host->address, addrlist->address,
3739 (addrlist->next == NULL)? "" : " (& others)", rs);
3741 /* Release serialization if set up */
3743 if (serialized) enq_end(serialize_key);
3745 /* If the result is DEFER, or if a host retry record is known to exist, we
3746 need to add an item to the retry chain for updating the retry database
3747 at the end of delivery. We only need to add the item to the top address,
3748 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
3749 for any other delivery attempts using the same address. (It is copied into
3750 the unusable tree at the outer level, so even if different address blocks
3751 contain the same address, it still won't get tried again.) */
3753 if (rc == DEFER || retry_host_key != NULL)
3755 int delete_flag = (rc != DEFER)? rf_delete : 0;
3756 if (retry_host_key == NULL)
3759 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3760 US"retry_include_ip_address", ob->retry_include_ip_address,
3761 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3762 incl_ip = TRUE; /* error; use most-specific retry record */
3764 retry_host_key = incl_ip ?
3765 string_sprintf("T:%S:%s%s", host->name, host->address, pistring) :
3766 string_sprintf("T:%S%s", host->name, pistring);
3769 /* If a delivery of another message over an existing SMTP connection
3770 yields DEFER, we do NOT set up retry data for the host. This covers the
3771 case when there are delays in routing the addresses in the second message
3772 that are so long that the server times out. This is alleviated by not
3773 routing addresses that previously had routing defers when handling an
3774 existing connection, but even so, this case may occur (e.g. if a
3775 previously happily routed address starts giving routing defers). If the
3776 host is genuinely down, another non-continued message delivery will
3777 notice it soon enough. */
3779 if (delete_flag != 0 || !continuing)
3780 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
3782 /* We may have tried an expired host, if its retry time has come; ensure
3783 the status reflects the expiry for the benefit of any other addresses. */
3787 host->status = (host_is_expired)?
3788 hstatus_unusable_expired : hstatus_unusable;
3789 host->why = hwhy_deferred;
3793 /* If message_defer is set (host was OK, but every recipient got deferred
3794 because of some message-specific problem), or if that had happened
3795 previously so that a message retry key exists, add an appropriate item
3796 to the retry chain. Note that if there was a message defer but now there is
3797 a host defer, the message defer record gets deleted. That seems perfectly
3798 reasonable. Also, stop the message from being remembered as waiting
3799 for specific hosts. */
3801 if (message_defer || retry_message_key != NULL)
3803 int delete_flag = message_defer? 0 : rf_delete;
3804 if (retry_message_key == NULL)
3807 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3808 US"retry_include_ip_address", ob->retry_include_ip_address,
3809 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3810 incl_ip = TRUE; /* error; use most-specific retry record */
3812 retry_message_key = incl_ip ?
3813 string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
3815 string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
3817 retry_add_item(addrlist, retry_message_key,
3818 rf_message | rf_host | delete_flag);
3819 update_waiting = FALSE;
3822 /* Any return other than DEFER (that is, OK or ERROR) means that the
3823 addresses have got their final statuses filled in for this host. In the OK
3824 case, see if any of them are deferred. */
3827 for (addr = addrlist; addr; addr = addr->next)
3828 if (addr->transport_return == DEFER)
3830 some_deferred = TRUE;
3834 /* If no addresses deferred or the result was ERROR, return. We do this for
3835 ERROR because a failing filter set-up or add_headers expansion is likely to
3836 fail for any host we try. */
3838 if (rc == ERROR || (rc == OK && !some_deferred))
3840 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3841 return TRUE; /* Each address has its status */
3844 /* If the result was DEFER or some individual addresses deferred, let
3845 the loop run to try other hosts with the deferred addresses, except for the
3846 case when we were trying to deliver down an existing channel and failed.
3847 Don't try any other hosts in this case. */
3849 if (continuing) break;
3851 /* If the whole delivery, or some individual addresses, were deferred and
3852 there are more hosts that could be tried, do not count this host towards
3853 the hosts_max_try limit if the age of the message is greater than the
3854 maximum retry time for this host. This means we may try try all hosts,
3855 ignoring the limit, when messages have been around for some time. This is
3856 important because if we don't try all hosts, the address will never time
3857 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
3859 if ((rc == DEFER || some_deferred) && nexthost != NULL)
3862 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
3864 if (retry != NULL && retry->rules != NULL)
3866 retry_rule *last_rule;
3867 for (last_rule = retry->rules;
3868 last_rule->next != NULL;
3869 last_rule = last_rule->next);
3870 timedout = time(NULL) - received_time > last_rule->timeout;
3872 else timedout = TRUE; /* No rule => timed out */
3876 unexpired_hosts_tried--;
3877 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
3878 "hosts_max_try (message older than host's retry time)\n");
3881 } /* End of loop for trying multiple hosts. */
3883 /* This is the end of the loop that repeats iff expired is TRUE and
3884 ob->delay_after_cutoff is FALSE. The second time round we will
3885 try those hosts that haven't been tried since the message arrived. */
3889 debug_printf("all IP addresses skipped or deferred at least one address\n");
3890 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
3891 debug_printf("retrying IP addresses not tried since message arrived\n");
3896 /* Get here if all IP addresses are skipped or defer at least one address. In
3897 MUA wrapper mode, this will happen only for connection or other non-message-
3898 specific failures. Force the delivery status for all addresses to FAIL. */
3902 for (addr = addrlist; addr != NULL; addr = addr->next)
3903 addr->transport_return = FAIL;
3907 /* In the normal, non-wrapper case, add a standard message to each deferred
3908 address if there hasn't been an error, that is, if it hasn't actually been
3909 tried this time. The variable "expired" will be FALSE if any deliveries were
3910 actually tried, or if there was at least one host that was not expired. That
3911 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
3912 a delivery has been tried, an error code will be set, and the failing of the
3913 message is handled by the retry code later.
3915 If queue_smtp is set, or this transport was called to send a subsequent message
3916 down an existing TCP/IP connection, and something caused the host not to be
3917 found, we end up here, but can detect these cases and handle them specially. */
3919 for (addr = addrlist; addr; addr = addr->next)
3921 /* If host is not NULL, it means that we stopped processing the host list
3922 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
3923 means we need to behave as if some hosts were skipped because their retry
3924 time had not come. Specifically, this prevents the address from timing out.
3925 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
3926 hosts were tried. */
3929 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
3932 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
3933 "hosts were tried\n");
3938 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
3939 setflag(addr, af_retry_skipped);
3942 if (queue_smtp) /* no deliveries attempted */
3944 addr->transport_return = DEFER;
3945 addr->basic_errno = 0;
3946 addr->message = US"SMTP delivery explicitly queued";
3949 else if ( addr->transport_return == DEFER
3950 && (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0)
3954 addr->basic_errno = ERRNO_HRETRY;
3955 if (continue_hostname)
3956 addr->message = US"no host found for existing SMTP connection";
3959 setflag(addr, af_pass_message); /* This is not a security risk */
3960 addr->message = string_sprintf(
3961 "all hosts%s have been failing for a long time %s",
3962 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"",
3963 ob->delay_after_cutoff
3964 ? US"(and retry time not reached)"
3965 : US"and were last tried after this message arrived");
3967 /* If we are already using fallback hosts, or there are no fallback hosts
3968 defined, convert the result to FAIL to cause a bounce. */
3970 if (addr->host_list == addr->fallback_hosts || !addr->fallback_hosts)
3971 addr->transport_return = FAIL;
3976 if (hosts_retry == hosts_total)
3977 s = "retry time not reached for any host%s";
3978 else if (hosts_fail == hosts_total)
3979 s = "all host address lookups%s failed permanently";
3980 else if (hosts_defer == hosts_total)
3981 s = "all host address lookups%s failed temporarily";
3982 else if (hosts_serial == hosts_total)
3983 s = "connection limit reached for all hosts%s";
3984 else if (hosts_fail+hosts_defer == hosts_total)
3985 s = "all host address lookups%s failed";
3987 s = "some host address lookups failed and retry time "
3988 "not reached for other hosts or connection limit reached%s";
3990 addr->message = string_sprintf(s,
3991 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"");
3996 /* Update the database which keeps information about which messages are waiting
3997 for which hosts to become available. For some message-specific errors, the
3998 update_waiting flag is turned off because we don't want follow-on deliveries in
3999 those cases. If this transport instance is explicitly limited to one message
4000 per connection then follow-on deliveries are not possible and there's no need
4001 to create/update the per-transport wait-<transport_name> database. */
4003 if (update_waiting && tblock->connection_max_messages != 1)
4004 transport_update_waiting(hostlist, tblock->name);
4008 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
4010 return TRUE; /* Each address has its status */
4015 /* End of transport/smtp.c */