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 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
120 { "hosts_try_dane", opt_stringptr,
121 (void *)offsetof(smtp_transport_options_block, hosts_try_dane) },
124 { "hosts_try_prdr", opt_stringptr,
125 (void *)offsetof(smtp_transport_options_block, hosts_try_prdr) },
128 { "hosts_verify_avoid_tls", opt_stringptr,
129 (void *)offsetof(smtp_transport_options_block, hosts_verify_avoid_tls) },
131 { "interface", opt_stringptr,
132 (void *)offsetof(smtp_transport_options_block, interface) },
133 { "keepalive", opt_bool,
134 (void *)offsetof(smtp_transport_options_block, keepalive) },
135 { "lmtp_ignore_quota", opt_bool,
136 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
137 { "max_rcpt", opt_int | opt_public,
138 (void *)offsetof(transport_instance, max_addresses) },
139 { "multi_domain", opt_expand_bool | opt_public,
140 (void *)offsetof(transport_instance, multi_domain) },
141 { "port", opt_stringptr,
142 (void *)offsetof(smtp_transport_options_block, port) },
143 { "protocol", opt_stringptr,
144 (void *)offsetof(smtp_transport_options_block, protocol) },
145 { "retry_include_ip_address", opt_expand_bool,
146 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
147 { "serialize_hosts", opt_stringptr,
148 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
149 { "size_addition", opt_int,
150 (void *)offsetof(smtp_transport_options_block, size_addition) }
152 ,{ "socks_proxy", opt_stringptr,
153 (void *)offsetof(smtp_transport_options_block, socks_proxy) }
156 ,{ "tls_certificate", opt_stringptr,
157 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
158 { "tls_crl", opt_stringptr,
159 (void *)offsetof(smtp_transport_options_block, tls_crl) },
160 { "tls_dh_min_bits", opt_int,
161 (void *)offsetof(smtp_transport_options_block, tls_dh_min_bits) },
162 { "tls_privatekey", opt_stringptr,
163 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
164 { "tls_require_ciphers", opt_stringptr,
165 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
166 { "tls_sni", opt_stringptr,
167 (void *)offsetof(smtp_transport_options_block, tls_sni) },
168 { "tls_tempfail_tryclear", opt_bool,
169 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
170 { "tls_try_verify_hosts", opt_stringptr,
171 (void *)offsetof(smtp_transport_options_block, tls_try_verify_hosts) },
172 { "tls_verify_cert_hostnames", opt_stringptr,
173 (void *)offsetof(smtp_transport_options_block,tls_verify_cert_hostnames)},
174 { "tls_verify_certificates", opt_stringptr,
175 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) },
176 { "tls_verify_hosts", opt_stringptr,
177 (void *)offsetof(smtp_transport_options_block, tls_verify_hosts) }
181 /* Size of the options list. An extern variable has to be used so that its
182 address can appear in the tables drtables.c. */
184 int smtp_transport_options_count =
185 sizeof(smtp_transport_options)/sizeof(optionlist);
187 /* Default private options block for the smtp transport. */
189 smtp_transport_options_block smtp_transport_option_defaults = {
191 NULL, /* fallback_hosts */
193 NULL, /* fallback_hostlist */
194 NULL, /* authenticated_sender */
195 US"$primary_hostname", /* helo_data */
196 NULL, /* interface */
198 US"smtp", /* protocol */
200 NULL, /* serialize_hosts */
201 NULL, /* hosts_try_auth */
202 NULL, /* hosts_require_auth */
203 #ifdef EXPERIMENTAL_DANE
204 NULL, /* hosts_try_dane */
205 NULL, /* hosts_require_dane */
208 US"*", /* hosts_try_prdr */
211 US"*", /* hosts_request_ocsp (except under DANE; tls_client_start()) */
212 NULL, /* hosts_require_ocsp */
214 NULL, /* hosts_require_tls */
215 NULL, /* hosts_avoid_tls */
216 NULL, /* hosts_verify_avoid_tls */
217 NULL, /* hosts_avoid_pipelining */
218 NULL, /* hosts_avoid_esmtp */
219 NULL, /* hosts_nopass_tls */
220 5*60, /* command_timeout */
221 5*60, /* connect_timeout; shorter system default overrides */
222 5*60, /* data timeout */
223 10*60, /* final timeout */
224 1024, /* size_addition */
225 5, /* hosts_max_try */
226 50, /* hosts_max_try_hardlimit */
227 TRUE, /* address_retry_include_sender */
228 FALSE, /* allow_localhost */
229 FALSE, /* authenticated_sender_force */
230 FALSE, /* gethostbyname */
231 TRUE, /* dns_qualify_single */
232 FALSE, /* dns_search_parents */
233 { NULL, NULL }, /* dnssec_domains {request,require} */
234 TRUE, /* delay_after_cutoff */
235 FALSE, /* hosts_override */
236 FALSE, /* hosts_randomize */
237 TRUE, /* keepalive */
238 FALSE, /* lmtp_ignore_quota */
239 NULL, /* expand_retry_include_ip_address */
240 TRUE /* retry_include_ip_address */
242 ,NULL /* socks_proxy */
245 ,NULL, /* tls_certificate */
247 NULL, /* tls_privatekey */
248 NULL, /* tls_require_ciphers */
250 US"system", /* tls_verify_certificates */
251 EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
252 /* tls_dh_min_bits */
253 TRUE, /* tls_tempfail_tryclear */
254 NULL, /* tls_verify_hosts */
255 US"*", /* tls_try_verify_hosts */
256 US"*" /* tls_verify_cert_hostnames */
259 , {NULL, /* dkim_canon */
260 NULL, /* dkim_domain */
261 NULL, /* dkim_private_key */
262 NULL, /* dkim_selector */
263 NULL, /* dkim_sign_headers */
264 NULL} /* dkim_strict */
268 /* some DSN flags for use later */
270 static int rf_list[] = {rf_notify_never, rf_notify_success,
271 rf_notify_failure, rf_notify_delay };
273 static uschar *rf_names[] = { US"NEVER", US"SUCCESS", US"FAILURE", US"DELAY" };
279 static uschar *smtp_command; /* Points to last cmd for error messages */
280 static uschar *mail_command; /* Points to MAIL cmd for error messages */
281 static BOOL update_waiting; /* TRUE to update the "wait" database */
282 static BOOL pipelining_active; /* current transaction is in pipe mode */
285 /*************************************************
286 * Setup entry point *
287 *************************************************/
289 /* This function is called when the transport is about to be used,
290 but before running it in a sub-process. It is used for two things:
292 (1) To set the fallback host list in addresses, when delivering.
293 (2) To pass back the interface, port, protocol, and other options, for use
294 during callout verification.
297 tblock pointer to the transport instance block
298 addrlist list of addresses about to be transported
299 tf if not NULL, pointer to block in which to return options
300 uid the uid that will be set (not used)
301 gid the gid that will be set (not used)
302 errmsg place for error message (not used)
304 Returns: OK always (FAIL, DEFER not used)
308 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
309 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
311 smtp_transport_options_block *ob =
312 (smtp_transport_options_block *)(tblock->options_block);
314 errmsg = errmsg; /* Keep picky compilers happy */
318 /* Pass back options if required. This interface is getting very messy. */
322 tf->interface = ob->interface;
324 tf->protocol = ob->protocol;
325 tf->hosts = ob->hosts;
326 tf->hosts_override = ob->hosts_override;
327 tf->hosts_randomize = ob->hosts_randomize;
328 tf->gethostbyname = ob->gethostbyname;
329 tf->qualify_single = ob->dns_qualify_single;
330 tf->search_parents = ob->dns_search_parents;
331 tf->helo_data = ob->helo_data;
334 /* Set the fallback host list for all the addresses that don't have fallback
335 host lists, provided that the local host wasn't present in the original host
338 if (!testflag(addrlist, af_local_host_removed))
340 for (; addrlist != NULL; addrlist = addrlist->next)
341 if (addrlist->fallback_hosts == NULL)
342 addrlist->fallback_hosts = ob->fallback_hostlist;
350 /*************************************************
351 * Initialization entry point *
352 *************************************************/
354 /* Called for each instance, after its options have been read, to
355 enable consistency checks to be done, or anything else that needs
358 Argument: pointer to the transport instance block
363 smtp_transport_init(transport_instance *tblock)
365 smtp_transport_options_block *ob =
366 (smtp_transport_options_block *)(tblock->options_block);
368 /* Retry_use_local_part defaults FALSE if unset */
370 if (tblock->retry_use_local_part == TRUE_UNSET)
371 tblock->retry_use_local_part = FALSE;
373 /* Set the default port according to the protocol */
375 if (ob->port == NULL)
376 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
377 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
379 /* Set up the setup entry point, to be called before subprocesses for this
382 tblock->setup = smtp_transport_setup;
384 /* Complain if any of the timeouts are zero. */
386 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
387 ob->final_timeout <= 0)
388 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
389 "command, data, or final timeout value is zero for %s transport",
392 /* If hosts_override is set and there are local hosts, set the global
393 flag that stops verify from showing router hosts. */
395 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
397 /* If there are any fallback hosts listed, build a chain of host items
398 for them, but do not do any lookups at this time. */
400 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
407 /*************************************************
408 * Set delivery info into all active addresses *
409 *************************************************/
411 /* Only addresses whose status is >= PENDING are relevant. A lesser
412 status means that an address is not currently being processed.
415 addrlist points to a chain of addresses
416 errno_value to put in each address's errno field
417 msg to put in each address's message field
418 rc to put in each address's transport_return field
419 pass_message if TRUE, set the "pass message" flag in the address
420 host if set, mark addrs as having used this host
421 smtp_greeting from peer
422 helo_response from peer
424 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
425 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
426 this particular type of timeout.
432 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
433 BOOL pass_message, host_item * host
434 #ifdef EXPERIMENTAL_DSN_INFO
435 , const uschar * smtp_greeting, const uschar * helo_response
441 if (errno_value == ERRNO_CONNECTTIMEOUT)
443 errno_value = ETIMEDOUT;
444 orvalue = RTEF_CTOUT;
446 for (addr = addrlist; addr; addr = addr->next)
447 if (addr->transport_return >= PENDING)
449 addr->basic_errno = errno_value;
450 addr->more_errno |= orvalue;
454 if (pass_message) setflag(addr, af_pass_message);
456 addr->transport_return = rc;
459 addr->host_used = host;
460 #ifdef EXPERIMENTAL_DSN_INFO
462 {uschar * s = Ustrchr(smtp_greeting, '\n'); if (s) *s = '\0';}
463 addr->smtp_greeting = smtp_greeting;
466 {uschar * s = Ustrchr(helo_response, '\n'); if (s) *s = '\0';}
467 addr->helo_response = helo_response;
474 set_errno_nohost(address_item *addrlist, int errno_value, uschar *msg, int rc,
477 set_errno(addrlist, errno_value, msg, rc, pass_message, NULL
478 #ifdef EXPERIMENTAL_DSN_INFO
485 /*************************************************
486 * Check an SMTP response *
487 *************************************************/
489 /* This function is given an errno code and the SMTP response buffer
490 to analyse, together with the host identification for generating messages. It
491 sets an appropriate message and puts the first digit of the response code into
492 the yield variable. If no response was actually read, a suitable digit is
496 host the current host, to get its name for messages
497 errno_value pointer to the errno value
498 more_errno from the top address for use with ERRNO_FILTER_FAIL
499 buffer the SMTP response buffer
500 yield where to put a one-digit SMTP response code
501 message where to put an errror message
502 pass_message set TRUE if message is an SMTP response
504 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
508 check_response(host_item *host, int *errno_value, int more_errno,
509 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
511 uschar * pl = pipelining_active ? US"pipelined " : US"";
513 *yield = '4'; /* Default setting is to give a temporary error */
515 /* Handle response timeout */
517 if (*errno_value == ETIMEDOUT)
519 *message = US string_sprintf("SMTP timeout after %s%s",
521 if (transport_count > 0)
522 *message = US string_sprintf("%s (%d bytes written)", *message,
527 /* Handle malformed SMTP response */
529 if (*errno_value == ERRNO_SMTPFORMAT)
531 const uschar *malfresp = string_printing(buffer);
532 while (isspace(*malfresp)) malfresp++;
533 *message = *malfresp == 0
534 ? string_sprintf("Malformed SMTP reply (an empty line) "
535 "in response to %s%s", pl, smtp_command)
536 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
537 pl, smtp_command, malfresp);
541 /* Handle a failed filter process error; can't send QUIT as we mustn't
544 if (*errno_value == ERRNO_FILTER_FAIL)
546 *message = US string_sprintf("transport filter process failed (%d)%s",
548 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
552 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
555 if (*errno_value == ERRNO_CHHEADER_FAIL)
558 US string_sprintf("failed to expand headers_add or headers_remove: %s",
559 expand_string_message);
563 /* Handle failure to write a complete data block */
565 if (*errno_value == ERRNO_WRITEINCOMPLETE)
567 *message = US string_sprintf("failed to write a data block");
572 /* Handle lack of advertised SMTPUTF8, for international message */
573 if (*errno_value == ERRNO_UTF8_FWD)
575 *message = US string_sprintf("utf8 support required but not offered for forwarding");
576 DEBUG(D_deliver|D_transport) debug_printf("%s\n", *message);
581 /* Handle error responses from the remote mailer. */
585 const uschar *s = string_printing(buffer);
586 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
587 "%s", pl, smtp_command, s);
588 *pass_message = TRUE;
593 /* No data was read. If there is no errno, this must be the EOF (i.e.
594 connection closed) case, which causes deferral. An explicit connection reset
595 error has the same effect. Otherwise, put the host's identity in the message,
596 leaving the errno value to be interpreted as well. In all cases, we have to
597 assume the connection is now dead. */
599 if (*errno_value == 0 || *errno_value == ECONNRESET)
601 *errno_value = ERRNO_SMTPCLOSED;
602 *message = US string_sprintf("Remote host closed connection "
603 "in response to %s%s", pl, smtp_command);
605 else *message = US string_sprintf("%s [%s]", host->name, host->address);
612 /*************************************************
613 * Write error message to logs *
614 *************************************************/
616 /* This writes to the main log and to the message log.
619 addr the address item containing error information
620 host the current host
626 write_logs(address_item *addr, host_item *host)
628 uschar * message = string_sprintf("H=%s [%s]", host->name, host->address);
630 if (LOGGING(outgoing_port))
631 message = string_sprintf("%s:%d", message,
632 host->port == PORT_NONE ? 25 : host->port);
635 message = string_sprintf("%s: %s", message, addr->message);
636 if (addr->basic_errno > 0)
637 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
638 log_write(0, LOG_MAIN, "%s", message);
639 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
643 const uschar * s = exim_errstr(addr->basic_errno);
644 log_write(0, LOG_MAIN, "%s %s", message, s);
645 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), message, s);
650 msglog_line(host_item * host, uschar * message)
652 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
653 host->name, host->address, message);
658 #ifndef DISABLE_EVENT
659 /*************************************************
660 * Post-defer action *
661 *************************************************/
663 /* This expands an arbitrary per-transport string.
664 It might, for example, be used to write to the database log.
667 addr the address item containing error information
668 host the current host
674 deferred_event_raise(address_item *addr, host_item *host)
676 uschar * action = addr->transport->event_action;
677 const uschar * save_domain;
683 save_domain = deliver_domain;
684 save_local = deliver_localpart;
686 /*XXX would ip & port already be set up? */
687 deliver_host_address = string_copy(host->address);
688 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
689 event_defer_errno = addr->basic_errno;
691 router_name = addr->router->name;
692 transport_name = addr->transport->name;
693 deliver_domain = addr->domain;
694 deliver_localpart = addr->local_part;
696 (void) event_raise(action, US"msg:host:defer",
698 ? addr->basic_errno > 0
699 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
700 : string_copy(addr->message)
701 : addr->basic_errno > 0
702 ? string_copy(US strerror(addr->basic_errno))
705 deliver_localpart = save_local;
706 deliver_domain = save_domain;
707 router_name = transport_name = NULL;
711 /*************************************************
712 * Synchronize SMTP responses *
713 *************************************************/
715 /* This function is called from smtp_deliver() to receive SMTP responses from
716 the server, and match them up with the commands to which they relate. When
717 PIPELINING is not in use, this function is called after every command, and is
718 therefore somewhat over-engineered, but it is simpler to use a single scheme
719 that works both with and without PIPELINING instead of having two separate sets
722 The set of commands that are buffered up with pipelining may start with MAIL
723 and may end with DATA; in between are RCPT commands that correspond to the
724 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
725 etc.) are never buffered.
727 Errors after MAIL or DATA abort the whole process leaving the response in the
728 buffer. After MAIL, pending responses are flushed, and the original command is
729 re-instated in big_buffer for error messages. For RCPT commands, the remote is
730 permitted to reject some recipient addresses while accepting others. However
731 certain errors clearly abort the whole process. Set the value in
732 transport_return to PENDING_OK if the address is accepted. If there is a
733 subsequent general error, it will get reset accordingly. If not, it will get
734 converted to OK at the end.
737 addrlist the complete address list
738 include_affixes TRUE if affixes include in RCPT
739 sync_addr ptr to the ptr of the one to start scanning at (updated)
740 host the host we are connected to
741 count the number of responses to read
743 include_sender true if 4xx retry is to include the sender it its key
744 pending_MAIL true if the first response is for MAIL
745 pending_DATA 0 if last command sent was not DATA
746 +1 if previously had a good recipient
747 -1 if not previously had a good recipient
748 inblock incoming SMTP block
749 timeout timeout value
750 buffer buffer for reading response
751 buffsize size of buffer
753 Returns: 3 if at least one address had 2xx and one had 5xx
754 2 if at least one address had 5xx but none had 2xx
755 1 if at least one host had a 2xx response, but none had 5xx
756 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
757 -1 timeout while reading RCPT response
758 -2 I/O or other non-response error for RCPT
759 -3 DATA or MAIL failed - errno and buffer set
763 sync_responses(address_item *addrlist, BOOL include_affixes,
764 address_item **sync_addr, host_item *host, int count,
765 BOOL address_retry_include_sender, BOOL pending_MAIL,
766 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
769 address_item *addr = *sync_addr;
772 /* Handle the response for a MAIL command. On error, reinstate the original
773 command in big_buffer for error message use, and flush any further pending
774 responses before returning, except after I/O errors and timeouts. */
779 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
781 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
782 if (errno == 0 && buffer[0] != 0)
784 uschar flushbuffer[4096];
786 if (buffer[0] == '4')
788 save_errno = ERRNO_MAIL4XX;
789 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
793 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
795 && (errno != 0 || flushbuffer[0] == 0))
801 if (pending_DATA) count--; /* Number of RCPT responses to come */
802 while (count-- > 0) /* Mark any pending addrs with the host used */
804 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
805 addr->host_used = host;
812 if (pending_DATA) count--; /* Number of RCPT responses to come */
814 /* Read and handle the required number of RCPT responses, matching each one up
815 with an address by scanning for the next address whose status is PENDING_DEFER.
820 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
822 /* The address was accepted */
823 addr->host_used = host;
825 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
828 addr->transport_return = PENDING_OK;
830 /* If af_dr_retry_exists is set, there was a routing delay on this address;
831 ensure that any address-specific retry record is expunged. We do this both
832 for the basic key and for the version that also includes the sender. */
834 if (testflag(addr, af_dr_retry_exists))
836 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
838 retry_add_item(addr, altkey, rf_delete);
839 retry_add_item(addr, addr->address_retry_key, rf_delete);
843 /* Timeout while reading the response */
845 else if (errno == ETIMEDOUT)
847 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
848 transport_rcpt_address(addr, include_affixes));
849 set_errno_nohost(addrlist, ETIMEDOUT, message, DEFER, FALSE);
850 retry_add_item(addr, addr->address_retry_key, 0);
851 update_waiting = FALSE;
855 /* Handle other errors in obtaining an SMTP response by returning -1. This
856 will cause all the addresses to be deferred. Restore the SMTP command in
857 big_buffer for which we are checking the response, so the error message
860 else if (errno != 0 || buffer[0] == 0)
862 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
863 transport_rcpt_address(addr, include_affixes));
867 /* Handle SMTP permanent and temporary response codes. */
872 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
873 "%s", transport_rcpt_address(addr, include_affixes),
874 string_printing(buffer));
875 setflag(addr, af_pass_message);
876 msglog_line(host, addr->message);
878 /* The response was 5xx */
880 if (buffer[0] == '5')
882 addr->transport_return = FAIL;
886 /* The response was 4xx */
890 addr->transport_return = DEFER;
891 addr->basic_errno = ERRNO_RCPT4XX;
892 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
894 #ifndef DISABLE_EVENT
895 event_defer_errno = addr->more_errno;
896 msg_event_raise(US"msg:rcpt:host:defer", addr);
899 /* Log temporary errors if there are more hosts to be tried.
900 If not, log this last one in the == line. */
903 log_write(0, LOG_MAIN, "H=%s [%s]: %s", host->name, host->address, addr->message);
905 #ifndef DISABLE_EVENT
907 msg_event_raise(US"msg:rcpt:defer", addr);
910 /* Do not put this message on the list of those waiting for specific
911 hosts, as otherwise it is likely to be tried too often. */
913 update_waiting = FALSE;
915 /* Add a retry item for the address so that it doesn't get tried again
916 too soon. If address_retry_include_sender is true, add the sender address
919 if (address_retry_include_sender)
921 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
923 retry_add_item(addr, altkey, 0);
925 else retry_add_item(addr, addr->address_retry_key, 0);
928 } /* Loop for next RCPT response */
930 /* Update where to start at for the next block of responses, unless we
931 have already handled all the addresses. */
933 if (addr != NULL) *sync_addr = addr->next;
935 /* Handle a response to DATA. If we have not had any good recipients, either
936 previously or in this block, the response is ignored. */
938 if (pending_DATA != 0 &&
939 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
944 if (pending_DATA > 0 || (yield & 1) != 0)
946 if (errno == 0 && buffer[0] == '4')
948 errno = ERRNO_DATA4XX;
949 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
953 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
954 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
955 "is in use and there were no good recipients\n", msg);
958 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
959 present) received 3xx. If any RCPTs were handled and yielded anything other
960 than 4xx, yield will be set non-zero. */
967 /* Do the client side of smtp-level authentication */
970 buffer EHLO response from server (gets overwritten)
971 addrlist chain of potential addresses to deliver
972 host host to deliver to
974 ibp, obp comms channel control blocks
977 OK Success, or failed (but not required): global "smtp_authenticated" set
978 DEFER Failed authentication (and was required)
979 ERROR Internal problem
981 FAIL_SEND Failed communications - transmit
986 smtp_auth(uschar *buffer, unsigned bufsize, address_item *addrlist, host_item *host,
987 smtp_transport_options_block *ob, BOOL is_esmtp,
988 smtp_inblock *ibp, smtp_outblock *obp)
991 uschar *fail_reason = US"server did not advertise AUTH support";
993 smtp_authenticated = FALSE;
994 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
995 require_auth = verify_check_given_host(&ob->hosts_require_auth, host);
997 if (is_esmtp && !regex_AUTH) regex_AUTH =
998 regex_must_compile(US"\\n250[\\s\\-]AUTH\\s+([\\-\\w\\s]+)(?:\\n|$)",
1001 if (is_esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
1003 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
1004 expand_nmax = -1; /* reset */
1006 /* Must not do this check until after we have saved the result of the
1007 regex match above. */
1009 if (require_auth == OK ||
1010 verify_check_given_host(&ob->hosts_try_auth, host) == OK)
1013 fail_reason = US"no common mechanisms were found";
1015 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1017 /* Scan the configured authenticators looking for one which is configured
1018 for use as a client, which is not suppressed by client_condition, and
1019 whose name matches an authentication mechanism supported by the server.
1020 If one is found, attempt to authenticate by calling its client function.
1023 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1027 (au->client_condition != NULL &&
1028 !expand_check_condition(au->client_condition, au->name,
1029 US"client authenticator")))
1031 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1033 (au->client)? "client_condition is false" :
1034 "not configured as a client");
1038 /* Loop to scan supported server mechanisms */
1043 int len = Ustrlen(au->public_name);
1044 while (isspace(*p)) p++;
1046 if (strncmpic(au->public_name, p, len) != 0 ||
1047 (p[len] != 0 && !isspace(p[len])))
1049 while (*p != 0 && !isspace(*p)) p++;
1053 /* Found data for a listed mechanism. Call its client entry. Set
1054 a flag in the outblock so that data is overwritten after sending so
1055 that reflections don't show it. */
1057 fail_reason = US"authentication attempt(s) failed";
1058 obp->authenticating = TRUE;
1059 rc = (au->info->clientcode)(au, ibp, obp,
1060 ob->command_timeout, buffer, bufsize);
1061 obp->authenticating = FALSE;
1062 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1065 /* A temporary authentication failure must hold up delivery to
1066 this host. After a permanent authentication failure, we carry on
1067 to try other authentication methods. If all fail hard, try to
1068 deliver the message unauthenticated unless require_auth was set. */
1073 smtp_authenticated = TRUE; /* stops the outer loop */
1074 client_authenticator = au->name;
1075 if (au->set_client_id != NULL)
1076 client_authenticated_id = expand_string(au->set_client_id);
1079 /* Failure after writing a command */
1084 /* Failure after reading a response */
1087 if (errno != 0 || buffer[0] != '5') return FAIL;
1088 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1089 au->name, host->name, host->address, buffer);
1092 /* Failure by some other means. In effect, the authenticator
1093 decided it wasn't prepared to handle this case. Typically this
1094 is the result of "fail" in an expansion string. Do we need to
1095 log anything here? Feb 2006: a message is now put in the buffer
1096 if logging is required. */
1100 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1101 "authentication H=%s [%s] %s", au->name, host->name,
1102 host->address, buffer);
1105 /* Internal problem, message in buffer. */
1108 set_errno_nohost(addrlist, ERRNO_AUTHPROB, string_copy(buffer),
1113 break; /* If not authenticated, try next authenticator */
1114 } /* Loop for scanning supported server mechanisms */
1115 } /* Loop for further authenticators */
1119 /* If we haven't authenticated, but are required to, give up. */
1121 if (require_auth == OK && !smtp_authenticated)
1123 set_errno_nohost(addrlist, ERRNO_AUTHFAIL,
1124 string_sprintf("authentication required but %s", fail_reason), DEFER,
1133 /* Construct AUTH appendix string for MAIL TO */
1136 buffer to build string
1137 addrlist chain of potential addresses to deliver
1138 ob transport options
1140 Globals smtp_authenticated
1141 client_authenticated_sender
1142 Return True on error, otherwise buffer has (possibly empty) terminated string
1146 smtp_mail_auth_str(uschar *buffer, unsigned bufsize, address_item *addrlist,
1147 smtp_transport_options_block *ob)
1149 uschar *local_authenticated_sender = authenticated_sender;
1152 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n", authenticated_sender, ob->authenticated_sender, smtp_authenticated?"Y":"N");
1155 if (ob->authenticated_sender != NULL)
1157 uschar *new = expand_string(ob->authenticated_sender);
1160 if (!expand_string_forcedfail)
1162 uschar *message = string_sprintf("failed to expand "
1163 "authenticated_sender: %s", expand_string_message);
1164 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1168 else if (new[0] != 0) local_authenticated_sender = new;
1171 /* Add the authenticated sender address if present */
1173 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1174 local_authenticated_sender != NULL)
1176 string_format(buffer, bufsize, " AUTH=%s",
1177 auth_xtextencode(local_authenticated_sender,
1178 Ustrlen(local_authenticated_sender)));
1179 client_authenticated_sender = string_copy(local_authenticated_sender);
1189 #ifdef EXPERIMENTAL_DANE
1190 /* Lookup TLSA record for host/port.
1191 Return: OK success with dnssec; DANE mode
1192 DEFER Do not use this host now, may retry later
1193 FAIL_FORCED No TLSA record; DANE not usable
1194 FAIL Do not use this connection
1198 tlsa_lookup(const host_item * host, dns_answer * dnsa, BOOL dane_required)
1200 /* move this out to host.c given the similarity to dns_lookup() ? */
1202 const uschar * fullname = buffer;
1204 /* TLSA lookup string */
1205 (void)sprintf(CS buffer, "_%d._tcp.%.256s", host->port, host->name);
1207 switch (dns_lookup(dnsa, buffer, T_TLSA, &fullname))
1210 if (!dns_is_secure(dnsa))
1212 log_write(0, LOG_MAIN, "DANE error: TLSA lookup not DNSSEC");
1218 return DEFER; /* just defer this TLS'd conn */
1220 case DNS_NODATA: /* no TLSA RR for this lookup */
1221 case DNS_NOMATCH: /* no records at all for this lookup */
1222 return dane_required ? FAIL : FAIL_FORCED;
1226 return dane_required ? FAIL : DEFER;
1233 typedef struct smtp_compare_s
1235 uschar *current_sender_address;
1236 struct transport_instance *tblock;
1240 Create a unique string that identifies this message, it is based on
1241 sender_address, helo_data and tls_certificate if enabled. */
1244 smtp_local_identity(uschar * sender, struct transport_instance * tblock)
1246 address_item * addr1;
1247 uschar * if1 = US"";
1248 uschar * helo1 = US"";
1250 uschar * tlsc1 = US"";
1252 uschar * save_sender_address = sender_address;
1253 uschar * local_identity = NULL;
1254 smtp_transport_options_block * ob =
1255 (smtp_transport_options_block *)tblock->options_block;
1257 sender_address = sender;
1259 addr1 = deliver_make_addr (sender, TRUE);
1260 deliver_set_expansions(addr1);
1263 if1 = expand_string(ob->interface);
1266 helo1 = expand_string(ob->helo_data);
1269 if (ob->tls_certificate)
1270 tlsc1 = expand_string(ob->tls_certificate);
1271 local_identity = string_sprintf ("%s^%s^%s", if1, helo1, tlsc1);
1273 local_identity = string_sprintf ("%s^%s", if1, helo1);
1276 deliver_set_expansions(NULL);
1277 sender_address = save_sender_address;
1279 return local_identity;
1284 /* This routine is a callback that is called from transport_check_waiting.
1285 This function will evaluate the incoming message versus the previous
1286 message. If the incoming message is using a different local identity then
1287 we will veto this new message. */
1290 smtp_are_same_identities(uschar * message_id, smtp_compare_t * s_compare)
1292 uschar * message_local_identity,
1293 * current_local_identity,
1294 * new_sender_address;
1296 current_local_identity =
1297 smtp_local_identity(s_compare->current_sender_address, s_compare->tblock);
1299 if (!(new_sender_address = deliver_get_sender_address(message_id)))
1302 message_local_identity =
1303 smtp_local_identity(new_sender_address, s_compare->tblock);
1305 return Ustrcmp(current_local_identity, message_local_identity) == 0;
1311 ehlo_response(uschar * buf, size_t bsize, uschar checks)
1314 if ( checks & PEER_OFFERED_TLS
1315 && pcre_exec(regex_STARTTLS, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1316 checks &= ~PEER_OFFERED_TLS;
1319 if ( checks & PEER_OFFERED_IGNQ
1320 && pcre_exec(regex_IGNOREQUOTA, NULL, CS buf, bsize, 0,
1321 PCRE_EOPT, NULL, 0) < 0)
1322 checks &= ~PEER_OFFERED_IGNQ;
1324 #ifndef DISABLE_PRDR
1325 if ( checks & PEER_OFFERED_PRDR
1326 && pcre_exec(regex_PRDR, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1327 checks &= ~PEER_OFFERED_PRDR;
1331 if ( checks & PEER_OFFERED_UTF8
1332 && pcre_exec(regex_UTF8, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1333 checks &= ~PEER_OFFERED_UTF8;
1336 if ( checks & PEER_OFFERED_DSN
1337 && pcre_exec(regex_DSN, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1338 checks &= ~PEER_OFFERED_DSN;
1340 if ( checks & PEER_OFFERED_PIPE
1341 && pcre_exec(regex_PIPELINING, NULL, CS buf, bsize, 0,
1342 PCRE_EOPT, NULL, 0) < 0)
1343 checks &= ~PEER_OFFERED_PIPE;
1345 if ( checks & PEER_OFFERED_SIZE
1346 && pcre_exec(regex_SIZE, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1347 checks &= ~PEER_OFFERED_SIZE;
1353 /*************************************************
1354 * Deliver address list to given host *
1355 *************************************************/
1357 /* If continue_hostname is not null, we get here only when continuing to
1358 deliver down an existing channel. The channel was passed as the standard
1359 input. TLS is never active on a passed channel; the previous process always
1360 closes it down before passing the connection on.
1362 Otherwise, we have to make a connection to the remote host, and do the
1363 initial protocol exchange.
1365 When running as an MUA wrapper, if the sender or any recipient is rejected,
1366 temporarily or permanently, we force failure for all recipients.
1369 addrlist chain of potential addresses to deliver; only those whose
1370 transport_return field is set to PENDING_DEFER are currently
1371 being processed; others should be skipped - they have either
1372 been delivered to an earlier host or IP address, or been
1373 failed by one of them.
1374 host host to deliver to
1375 host_af AF_INET or AF_INET6
1376 port default TCP/IP port to use, in host byte order
1377 interface interface to bind to, or NULL
1378 tblock transport instance block
1379 message_defer set TRUE if yield is OK, but all addresses were deferred
1380 because of a non-recipient, non-host failure, that is, a
1381 4xx response to MAIL FROM, DATA, or ".". This is a defer
1382 that is specific to the message.
1383 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1384 a second attempt after TLS initialization fails
1386 Returns: OK - the connection was made and the delivery attempted;
1387 the result for each address is in its data block.
1388 DEFER - the connection could not be made, or something failed
1389 while setting up the SMTP session, or there was a
1390 non-message-specific error, such as a timeout.
1391 ERROR - a filter command is specified for this transport,
1392 and there was a problem setting it up; OR helo_data
1393 or add_headers or authenticated_sender is specified
1394 for this transport, and the string failed to expand
1398 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
1399 uschar *interface, transport_instance *tblock,
1400 BOOL *message_defer, BOOL suppress_tls)
1403 address_item *sync_addr;
1404 address_item *first_addr = addrlist;
1409 time_t start_delivery_time = time(NULL);
1410 smtp_transport_options_block *ob =
1411 (smtp_transport_options_block *)(tblock->options_block);
1412 BOOL lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
1413 BOOL smtps = strcmpic(ob->protocol, US"smtps") == 0;
1415 BOOL send_rset = TRUE;
1416 BOOL send_quit = TRUE;
1417 BOOL setting_up = TRUE;
1418 BOOL completed_address = FALSE;
1421 BOOL pass_message = FALSE;
1422 uschar peer_offered = 0; /*XXX should this be handed on cf. tls_offered, smtp_use_dsn ? */
1423 #ifndef DISABLE_PRDR
1427 BOOL utf8_needed = FALSE;
1429 BOOL dsn_all_lasthop = TRUE;
1430 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1432 BOOL dane_required = verify_check_given_host(&ob->hosts_require_dane, host) == OK;
1433 dns_answer tlsa_dnsa;
1435 smtp_inblock inblock;
1436 smtp_outblock outblock;
1437 int max_rcpt = tblock->max_addresses;
1438 uschar *igquotstr = US"";
1440 #ifdef EXPERIMENTAL_DSN_INFO
1441 uschar *smtp_greeting = NULL;
1442 uschar *helo_response = NULL;
1444 uschar *helo_data = NULL;
1446 uschar *message = NULL;
1447 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
1449 uschar buffer[4096];
1450 uschar inbuffer[4096];
1451 uschar outbuffer[4096];
1453 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
1455 *message_defer = FALSE;
1456 smtp_command = US"initial connection";
1457 if (max_rcpt == 0) max_rcpt = 999999;
1459 /* Set up the buffer for reading SMTP response packets. */
1461 inblock.buffer = inbuffer;
1462 inblock.buffersize = sizeof(inbuffer);
1463 inblock.ptr = inbuffer;
1464 inblock.ptrend = inbuffer;
1466 /* Set up the buffer for holding SMTP commands while pipelining */
1468 outblock.buffer = outbuffer;
1469 outblock.buffersize = sizeof(outbuffer);
1470 outblock.ptr = outbuffer;
1471 outblock.cmd_count = 0;
1472 outblock.authenticating = FALSE;
1474 /* Reset the parameters of a TLS session. */
1477 tls_out.cipher = NULL; /* the one we may use for this transport */
1478 tls_out.ourcert = NULL;
1479 tls_out.peercert = NULL;
1480 tls_out.peerdn = NULL;
1481 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1484 tls_out.ocsp = OCSP_NOT_REQ;
1486 /* Flip the legacy TLS-related variables over to the outbound set in case
1487 they're used in the context of the transport. Don't bother resetting
1488 afterward as we're in a subprocess. */
1490 tls_modify_variables(&tls_out);
1495 set_errno_nohost(addrlist, ERRNO_TLSFAILURE, US"TLS support not available",
1501 /* Make a connection to the host if this isn't a continued delivery, and handle
1502 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
1503 specially so they can be identified for retries. */
1505 if (continue_hostname == NULL)
1507 /* This puts port into host->port */
1508 inblock.sock = outblock.sock =
1509 smtp_connect(host, host_af, port, interface, ob->connect_timeout, tblock);
1511 if (inblock.sock < 0)
1513 set_errno_nohost(addrlist, (errno == ETIMEDOUT)? ERRNO_CONNECTTIMEOUT : errno,
1514 NULL, DEFER, FALSE);
1518 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1520 tls_out.dane_verified = FALSE;
1521 tls_out.tlsa_usage = 0;
1523 if (host->dnssec == DS_YES)
1526 || verify_check_given_host(&ob->hosts_try_dane, host) == OK
1528 switch (rc = tlsa_lookup(host, &tlsa_dnsa, dane_required))
1530 case OK: dane = TRUE; break;
1531 case FAIL_FORCED: break;
1532 default: set_errno_nohost(addrlist, ERRNO_DNSDEFER,
1533 string_sprintf("DANE error: tlsa lookup %s",
1534 rc == DEFER ? "DEFER" : "FAIL"),
1539 else if (dane_required)
1541 set_errno_nohost(addrlist, ERRNO_DNSDEFER,
1542 string_sprintf("DANE error: %s lookup not DNSSEC", host->name),
1548 ob->tls_tempfail_tryclear = FALSE;
1552 /* Expand the greeting message while waiting for the initial response. (Makes
1553 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1554 delayed till here so that $sending_interface and $sending_port are set. */
1556 helo_data = expand_string(ob->helo_data);
1560 uschar * errstr = NULL;
1561 if ((helo_data = string_domain_utf8_to_alabel(helo_data, &errstr)), errstr)
1563 errstr = string_sprintf("failed to expand helo_data: %s", errstr);
1564 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE);
1571 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1572 is nevertheless a reasonably clean way of programming this kind of logic,
1573 where you want to escape on any error. */
1577 BOOL good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
1578 '2', ob->command_timeout);
1579 #ifdef EXPERIMENTAL_DSN_INFO
1580 smtp_greeting = string_copy(buffer);
1582 if (!good_response) goto RESPONSE_FAILED;
1584 #ifndef DISABLE_EVENT
1587 lookup_dnssec_authenticated = host->dnssec==DS_YES ? US"yes"
1588 : host->dnssec==DS_NO ? US"no" : NULL;
1589 s = event_raise(tblock->event_action, US"smtp:connect", buffer);
1592 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL,
1593 string_sprintf("deferred by smtp:connect event expansion: %s", s),
1601 /* Now check if the helo_data expansion went well, and sign off cleanly if
1604 if (helo_data == NULL)
1606 uschar *message = string_sprintf("failed to expand helo_data: %s",
1607 expand_string_message);
1608 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1614 /** Debugging without sending a message
1615 addrlist->transport_return = DEFER;
1619 /* Errors that occur after this point follow an SMTP command, which is
1620 left in big_buffer by smtp_write_command() for use in error messages. */
1622 smtp_command = big_buffer;
1624 /* Tell the remote who we are...
1626 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1627 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1628 greeting is of this form. The assumption was that the far end supports it
1629 properly... but experience shows that there are some that give 5xx responses,
1630 even though the banner includes "ESMTP" (there's a bloody-minded one that
1631 says "ESMTP not spoken here"). Cope with that case.
1633 September 2000: Time has passed, and it seems reasonable now to always send
1634 EHLO at the start. It is also convenient to make the change while installing
1637 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1638 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1639 would be no way to send out the mails, so there is now a host list
1640 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1641 PIPELINING problem as well. Maybe it can also be useful to cure other
1642 problems with broken servers.
1644 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1645 Then somebody tried it with a Microsoft mailer... It seems that all other
1646 mailers use upper case for some reason (the RFC is quite clear about case
1647 independence) so, for peace of mind, I gave in. */
1649 esmtp = verify_check_given_host(&ob->hosts_avoid_esmtp, host) != OK;
1651 /* Alas; be careful, since this goto is not an error-out, so conceivably
1652 we might set data between here and the target which we assume to exist
1653 and be usable. I can see this coming back to bite us. */
1658 suppress_tls = FALSE;
1659 ob->tls_tempfail_tryclear = FALSE;
1660 smtp_command = US"SSL-on-connect";
1667 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1668 lmtp? "LHLO" : "EHLO", helo_data) < 0)
1670 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1671 ob->command_timeout))
1673 if (errno != 0 || buffer[0] == 0 || lmtp)
1675 #ifdef EXPERIMENTAL_DSN_INFO
1676 helo_response = string_copy(buffer);
1678 goto RESPONSE_FAILED;
1682 #ifdef EXPERIMENTAL_DSN_INFO
1683 helo_response = string_copy(buffer);
1689 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1696 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1698 good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
1699 '2', ob->command_timeout);
1700 #ifdef EXPERIMENTAL_DSN_INFO
1701 helo_response = string_copy(buffer);
1703 if (!good_response) goto RESPONSE_FAILED;
1707 peer_offered = ehlo_response(buffer, Ustrlen(buffer),
1708 PEER_OFFERED_TLS /* others checked later */
1711 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1714 tls_offered = !!(peer_offered & PEER_OFFERED_TLS);
1718 /* For continuing deliveries down the same channel, the socket is the standard
1719 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1720 below). Set up the pointer to where subsequent commands will be left, for
1721 error messages. Note that smtp_use_size and smtp_use_pipelining will have been
1722 set from the command line if they were set in the process that passed the
1725 /*XXX continue case needs to propagate DSN_INFO, prob. in deliver.c
1726 as the contine goes via transport_pass_socket() and doublefork and exec.
1727 It does not wait. Unclear how we keep separate host's responses
1728 separate - we could match up by host ip+port as a bodge. */
1732 inblock.sock = outblock.sock = fileno(stdin);
1733 smtp_command = big_buffer;
1734 host->port = port; /* Record the port that was used */
1737 /* If TLS is available on this connection, whether continued or not, attempt to
1738 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1739 send another EHLO - the server may give a different answer in secure mode. We
1740 use a separate buffer for reading the response to STARTTLS so that if it is
1741 negative, the original EHLO data is available for subsequent analysis, should
1742 the client not be required to use TLS. If the response is bad, copy the buffer
1743 for error analysis. */
1748 && verify_check_given_host(&ob->hosts_avoid_tls, host) != OK)
1750 uschar buffer2[4096];
1751 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1754 /* If there is an I/O error, transmission of this message is deferred. If
1755 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1756 false, we also defer. However, if there is a temporary rejection of STARTTLS
1757 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1758 STARTTLS, we carry on. This means we will try to send the message in clear,
1759 unless the host is in hosts_require_tls (tested below). */
1761 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1762 ob->command_timeout))
1766 || (buffer2[0] == '4' && !ob->tls_tempfail_tryclear)
1769 Ustrncpy(buffer, buffer2, sizeof(buffer));
1770 goto RESPONSE_FAILED;
1774 /* STARTTLS accepted: try to negotiate a TLS session. */
1779 int rc = tls_client_start(inblock.sock, host, addrlist, tblock
1780 # ifdef EXPERIMENTAL_DANE
1781 , dane ? &tlsa_dnsa : NULL
1785 /* TLS negotiation failed; give an error. From outside, this function may
1786 be called again to try in clear on a new connection, if the options permit
1787 it for this host. */
1791 # ifdef EXPERIMENTAL_DANE
1792 if (rc == DEFER && dane)
1794 log_write(0, LOG_MAIN,
1795 "DANE attempt failed; no TLS connection to %s [%s]",
1796 host->name, host->address);
1800 save_errno = ERRNO_TLSFAILURE;
1801 message = US"failure while setting up TLS session";
1806 /* TLS session is set up */
1808 for (addr = addrlist; addr; addr = addr->next)
1809 if (addr->transport_return == PENDING_DEFER)
1811 addr->cipher = tls_out.cipher;
1812 addr->ourcert = tls_out.ourcert;
1813 addr->peercert = tls_out.peercert;
1814 addr->peerdn = tls_out.peerdn;
1815 addr->ocsp = tls_out.ocsp;
1820 /* if smtps, we'll have smtp_command set to something else; always safe to
1822 smtp_command = big_buffer;
1824 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1825 helo_data is null, we are dealing with a connection that was passed from
1826 another process, and so we won't have expanded helo_data above. We have to
1827 expand it here. $sending_ip_address and $sending_port are set up right at the
1828 start of the Exim process (in exim.c). */
1830 if (tls_out.active >= 0)
1835 if (helo_data == NULL)
1837 helo_data = expand_string(ob->helo_data);
1838 if (helo_data == NULL)
1840 uschar *message = string_sprintf("failed to expand helo_data: %s",
1841 expand_string_message);
1842 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1848 /* For SMTPS we need to wait for the initial OK response. */
1851 good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
1852 '2', ob->command_timeout);
1853 #ifdef EXPERIMENTAL_DSN_INFO
1854 smtp_greeting = string_copy(buffer);
1856 if (!good_response) goto RESPONSE_FAILED;
1860 greeting_cmd = "EHLO";
1863 greeting_cmd = "HELO";
1865 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1868 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1869 lmtp? "LHLO" : greeting_cmd, helo_data) < 0)
1871 good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
1872 '2', ob->command_timeout);
1873 #ifdef EXPERIMENTAL_DSN_INFO
1874 helo_response = string_copy(buffer);
1876 if (!good_response) goto RESPONSE_FAILED;
1879 /* If the host is required to use a secure channel, ensure that we
1883 # ifdef EXPERIMENTAL_DANE
1886 || verify_check_given_host(&ob->hosts_require_tls, host) == OK
1889 save_errno = ERRNO_TLSREQUIRED;
1890 message = string_sprintf("a TLS session is required, but %s",
1891 tls_offered ? "an attempt to start TLS failed"
1892 : "the server did not offer TLS support");
1895 #endif /*SUPPORT_TLS*/
1897 /* If TLS is active, we have just started it up and re-done the EHLO command,
1898 so its response needs to be analyzed. If TLS is not active and this is a
1899 continued session down a previously-used socket, we haven't just done EHLO, so
1902 if (continue_hostname == NULL
1904 || tls_out.active >= 0
1909 peer_offered = ehlo_response(buffer, Ustrlen(buffer),
1911 | (lmtp && ob->lmtp_ignore_quota ? PEER_OFFERED_IGNQ : 0)
1914 | (addrlist->prop.utf8_msg ? PEER_OFFERED_UTF8 : 0)
1915 /*XXX if we hand peercaps on to continued-conn processes,
1916 must not depend on this addr */
1920 | (ob->size_addition >= 0 ? PEER_OFFERED_SIZE : 0)
1923 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
1924 lmtp_ignore_quota option was set. */
1926 igquotstr = peer_offered & PEER_OFFERED_IGNQ ? US" IGNOREQUOTA" : US"";
1928 /* If the response to EHLO specified support for the SIZE parameter, note
1929 this, provided size_addition is non-negative. */
1931 smtp_use_size = !!(peer_offered & PEER_OFFERED_SIZE);
1933 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
1934 the current host, esmtp will be false, so PIPELINING can never be used. If
1935 the current host matches hosts_avoid_pipelining, don't do it. */
1937 smtp_use_pipelining = peer_offered & PEER_OFFERED_PIPE
1938 && verify_check_given_host(&ob->hosts_avoid_pipelining, host) != OK;
1940 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
1941 smtp_use_pipelining ? "" : "not ");
1943 #ifndef DISABLE_PRDR
1944 if ( peer_offered & PEER_OFFERED_PRDR
1945 && verify_check_given_host(&ob->hosts_try_prdr, host) != OK)
1946 peer_offered &= ~PEER_OFFERED_PRDR;
1948 if (peer_offered & PEER_OFFERED_PRDR)
1949 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1952 /* Note if the server supports DSN */
1953 smtp_use_dsn = !!(peer_offered & PEER_OFFERED_DSN);
1954 DEBUG(D_transport) debug_printf("%susing DSN\n", smtp_use_dsn ? "" : "not ");
1956 /* Note if the response to EHLO specifies support for the AUTH extension.
1957 If it has, check that this host is one we want to authenticate to, and do
1958 the business. The host name and address must be available when the
1959 authenticator's client driver is running. */
1961 switch (yield = smtp_auth(buffer, sizeof(buffer), addrlist, host,
1962 ob, esmtp, &inblock, &outblock))
1964 default: goto SEND_QUIT;
1966 case FAIL_SEND: goto SEND_FAILED;
1967 case FAIL: goto RESPONSE_FAILED;
1970 pipelining_active = smtp_use_pipelining;
1972 /* The setting up of the SMTP call is now complete. Any subsequent errors are
1973 message-specific. */
1978 if (addrlist->prop.utf8_msg)
1980 utf8_needed = !addrlist->prop.utf8_downcvt
1981 && !addrlist->prop.utf8_downcvt_maybe;
1982 DEBUG(D_transport) if (!utf8_needed) debug_printf("utf8: %s downconvert\n",
1983 addrlist->prop.utf8_downcvt ? "mandatory" : "optional");
1986 /* If this is an international message we need the host to speak SMTPUTF8 */
1987 if (utf8_needed && !(peer_offered & PEER_OFFERED_UTF8))
1989 errno = ERRNO_UTF8_FWD;
1990 goto RESPONSE_FAILED;
1994 /* If there is a filter command specified for this transport, we can now
1995 set it up. This cannot be done until the identify of the host is known. */
1997 if (tblock->filter_command != NULL)
2001 sprintf(CS buffer, "%.50s transport", tblock->name);
2002 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
2003 TRUE, DEFER, addrlist, buffer, NULL);
2004 transport_filter_timeout = tblock->filter_timeout;
2006 /* On failure, copy the error to all addresses, abandon the SMTP call, and
2011 set_errno_nohost(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
2019 /* For messages that have more than the maximum number of envelope recipients,
2020 we want to send several transactions down the same SMTP connection. (See
2021 comments in deliver.c as to how this reconciles, heuristically, with
2022 remote_max_parallel.) This optimization was added to Exim after the following
2023 code was already working. The simplest way to put it in without disturbing the
2024 code was to use a goto to jump back to this point when there is another
2025 transaction to handle. */
2028 sync_addr = first_addr;
2032 completed_address = FALSE;
2035 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
2036 qualification, send it, adding something to the message size to allow for
2037 imprecision and things that get added en route. Exim keeps the number of lines
2038 in a message, so we can give an accurate value for the original message, but we
2039 need some additional to handle added headers. (Double "." characters don't get
2040 included in the count.) */
2047 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
2051 #ifndef DISABLE_PRDR
2052 prdr_active = FALSE;
2053 if (peer_offered & PEER_OFFERED_PRDR)
2054 for (addr = first_addr; addr; addr = addr->next)
2055 if (addr->transport_return == PENDING_DEFER)
2057 for (addr = addr->next; addr; addr = addr->next)
2058 if (addr->transport_return == PENDING_DEFER)
2059 { /* at least two recipients to send */
2061 sprintf(CS p, " PRDR"); p += 5;
2069 if ( addrlist->prop.utf8_msg
2070 && !addrlist->prop.utf8_downcvt
2071 && peer_offered & PEER_OFFERED_UTF8
2073 sprintf(CS p, " SMTPUTF8"), p += 9;
2076 /* check if all addresses have lasthop flag */
2077 /* do not send RET and ENVID if true */
2078 for (dsn_all_lasthop = TRUE, addr = first_addr;
2079 address_count < max_rcpt && addr != NULL;
2081 if ((addr->dsn_flags & rf_dsnlasthop) != 1)
2083 dsn_all_lasthop = FALSE;
2087 /* Add any DSN flags to the mail command */
2089 if (smtp_use_dsn && !dsn_all_lasthop)
2091 if (dsn_ret == dsn_ret_hdrs)
2093 Ustrcpy(p, " RET=HDRS"); p += 9;
2095 else if (dsn_ret == dsn_ret_full)
2097 Ustrcpy(p, " RET=FULL"); p += 9;
2099 if (dsn_envid != NULL)
2101 string_format(p, sizeof(buffer) - (p-buffer), " ENVID=%s", dsn_envid);
2106 /* If an authenticated_sender override has been specified for this transport
2107 instance, expand it. If the expansion is forced to fail, and there was already
2108 an authenticated_sender for this message, the original value will be used.
2109 Other expansion failures are serious. An empty result is ignored, but there is
2110 otherwise no check - this feature is expected to be used with LMTP and other
2111 cases where non-standard addresses (e.g. without domains) might be required. */
2113 if (smtp_mail_auth_str(p, sizeof(buffer) - (p-buffer), addrlist, ob))
2119 /* From here until we send the DATA command, we can make use of PIPELINING
2120 if the server host supports it. The code has to be able to check the responses
2121 at any point, for when the buffer fills up, so we write it totally generally.
2122 When PIPELINING is off, each command written reports that it has flushed the
2125 pending_MAIL = TRUE; /* The block starts with MAIL */
2128 uschar * s = return_path;
2130 uschar * errstr = NULL;
2132 /* If we must downconvert, do the from-address here. Remember we had to
2133 for the to-addresses (done below), and also (ugly) for re-doing when building
2134 the delivery log line. */
2136 if ( addrlist->prop.utf8_msg
2137 && (addrlist->prop.utf8_downcvt || !(peer_offered & PEER_OFFERED_UTF8))
2140 if (s = string_address_utf8_to_alabel(return_path, &errstr), errstr)
2142 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE);
2146 setflag(addrlist, af_utf8_downcvt);
2150 rc = smtp_write_command(&outblock, smtp_use_pipelining,
2151 "MAIL FROM:<%s>%s\r\n", s, buffer);
2154 mail_command = string_copy(big_buffer); /* Save for later error message */
2158 case -1: /* Transmission error */
2161 case +1: /* Block was sent */
2162 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2163 ob->command_timeout))
2165 if (errno == 0 && buffer[0] == '4')
2167 errno = ERRNO_MAIL4XX;
2168 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2170 goto RESPONSE_FAILED;
2172 pending_MAIL = FALSE;
2176 /* Pass over all the relevant recipient addresses for this host, which are the
2177 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
2178 several before we have to read the responses for those seen so far. This
2179 checking is done by a subroutine because it also needs to be done at the end.
2180 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
2181 the next one if not all are sent.
2183 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
2184 last address because we want to abort if any recipients have any kind of
2185 problem, temporary or permanent. We know that all recipient addresses will have
2186 the PENDING_DEFER status, because only one attempt is ever made, and we know
2187 that max_rcpt will be large, so all addresses will be done at once. */
2189 for (addr = first_addr;
2190 addr && address_count < max_rcpt;
2197 addr->dsn_aware = smtp_use_dsn ? dsn_support_yes : dsn_support_no;
2199 if (addr->transport_return != PENDING_DEFER) continue;
2202 no_flush = smtp_use_pipelining && (!mua_wrapper || addr->next);
2204 /* Add any DSN flags to the rcpt command and add to the sent string */
2209 if (smtp_use_dsn && !(addr->dsn_flags & rf_dsnlasthop))
2211 if ((addr->dsn_flags & rf_dsnflags) != 0)
2215 Ustrcpy(p, " NOTIFY=");
2217 for (i = 0; i < 4; i++)
2218 if ((addr->dsn_flags & rf_list[i]) != 0)
2220 if (!first) *p++ = ',';
2222 Ustrcpy(p, rf_names[i]);
2227 if (addr->dsn_orcpt)
2229 string_format(p, sizeof(buffer) - (p-buffer), " ORCPT=%s",
2235 /* Now send the RCPT command, and process outstanding responses when
2236 necessary. After a timeout on RCPT, we just end the function, leaving the
2237 yield as OK, because this error can often mean that there is a problem with
2238 just one address, so we don't want to delay the host. */
2240 rcpt_addr = transport_rcpt_address(addr, tblock->rcpt_include_affixes);
2244 uschar * dummy_errstr;
2245 if ( testflag(addrlist, af_utf8_downcvt)
2246 && (rcpt_addr = string_address_utf8_to_alabel(rcpt_addr, &dummy_errstr),
2250 errno = ERRNO_EXPANDFAIL;
2256 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s%s\r\n",
2257 rcpt_addr, igquotstr, buffer);
2259 if (count < 0) goto SEND_FAILED;
2262 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
2263 &sync_addr, host, count, ob->address_retry_include_sender,
2264 pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
2267 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2268 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2271 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2272 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2273 case 0: /* No 2xx or 5xx, but no probs */
2276 case -1: goto END_OFF; /* Timeout on RCPT */
2277 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
2279 pending_MAIL = FALSE; /* Dealt with MAIL */
2281 } /* Loop for next address */
2283 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
2284 permanently or temporarily. We should have flushed and synced after the last
2289 address_item *badaddr;
2290 for (badaddr = first_addr; badaddr; badaddr = badaddr->next)
2291 if (badaddr->transport_return != PENDING_OK)
2293 /*XXX could we find a better errno than 0 here? */
2294 set_errno_nohost(addrlist, 0, badaddr->message, FAIL,
2295 testflag(badaddr, af_pass_message));
2301 /* If ok is TRUE, we know we have got at least one good recipient, and must now
2302 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
2303 have a good recipient buffered up if we are pipelining. We don't want to waste
2304 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
2305 are pipelining. The responses are all handled by sync_responses(). */
2307 if (ok || (smtp_use_pipelining && !mua_wrapper))
2309 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
2310 if (count < 0) goto SEND_FAILED;
2311 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
2312 host, count, ob->address_retry_include_sender, pending_MAIL,
2313 ok? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
2315 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2316 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2319 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2320 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2321 case 0: break; /* No 2xx or 5xx, but no probs */
2323 case -1: goto END_OFF; /* Timeout on RCPT */
2324 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2326 pipelining_active = FALSE;
2329 /* Save the first address of the next batch. */
2333 /* If there were no good recipients (but otherwise there have been no
2334 problems), just set ok TRUE, since we have handled address-specific errors
2335 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
2336 for handling the SMTP dot-handling protocol, flagging to apply to headers as
2337 well as body. Set the appropriate timeout value to be used for each chunk.
2338 (Haven't been able to make it work using select() for writing yet.) */
2344 transport_ctx tctx = {
2347 US".", US"..", /* Escaping strings */
2348 topt_use_crlf | topt_end_dot | topt_escape_headers
2349 | (tblock->body_only ? topt_no_headers : 0)
2350 | (tblock->headers_only ? topt_no_body : 0)
2351 | (tblock->return_path_add ? topt_add_return_path : 0)
2352 | (tblock->delivery_date_add ? topt_add_delivery_date : 0)
2353 | (tblock->envelope_to_add ? topt_add_envelope_to : 0)
2356 sigalrm_seen = FALSE;
2357 transport_write_timeout = ob->data_timeout;
2358 smtp_command = US"sending data block"; /* For error messages */
2359 DEBUG(D_transport|D_v)
2360 debug_printf(" SMTP>> writing message and terminating \".\"\n");
2361 transport_count = 0;
2363 #ifndef DISABLE_DKIM
2364 ok = dkim_transport_write_message(inblock.sock, &tctx, &ob->dkim);
2366 ok = transport_write_message(inblock.sock, &tctx, 0);
2369 /* transport_write_message() uses write() because it is called from other
2370 places to write to non-sockets. This means that under some OS (e.g. Solaris)
2371 it can exit with "Broken pipe" as its error. This really means that the
2372 socket got closed at the far end. */
2374 transport_write_timeout = 0; /* for subsequent transports */
2376 /* Failure can either be some kind of I/O disaster (including timeout),
2377 or the failure of a transport filter or the expansion of added headers. */
2381 buffer[0] = 0; /* There hasn't been a response */
2382 goto RESPONSE_FAILED;
2385 /* We used to send the terminating "." explicitly here, but because of
2386 buffering effects at both ends of TCP/IP connections, you don't gain
2387 anything by keeping it separate, so it might as well go in the final
2388 data buffer for efficiency. This is now done by setting the topt_end_dot
2391 smtp_command = US"end of data";
2393 #ifndef DISABLE_PRDR
2394 /* For PRDR we optionally get a partial-responses warning
2395 * followed by the individual responses, before going on with
2396 * the overall response. If we don't get the warning then deal
2397 * with per non-PRDR. */
2400 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '3',
2402 if (!ok && errno == 0)
2405 case '2': prdr_active = FALSE;
2408 case '4': errno = ERRNO_DATA4XX;
2409 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2416 /* For non-PRDR SMTP, we now read a single response that applies to the
2417 whole message. If it is OK, then all the addresses have been delivered. */
2421 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2423 if (!ok && errno == 0 && buffer[0] == '4')
2425 errno = ERRNO_DATA4XX;
2426 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2430 /* For LMTP, we get back a response for every RCPT command that we sent;
2431 some may be accepted and some rejected. For those that get a response, their
2432 status is fixed; any that are accepted have been handed over, even if later
2433 responses crash - at least, that's how I read RFC 2033.
2435 If all went well, mark the recipient addresses as completed, record which
2436 host/IPaddress they were delivered to, and cut out RSET when sending another
2437 message down the same channel. Write the completed addresses to the journal
2438 now so that they are recorded in case there is a crash of hardware or
2439 software before the spool gets updated. Also record the final SMTP
2440 confirmation if needed (for SMTP only). */
2445 int delivery_time = (int)(time(NULL) - start_delivery_time);
2447 uschar *conf = NULL;
2450 pipelining_active = FALSE;
2452 /* Set up confirmation if needed - applies only to SMTP */
2455 #ifdef DISABLE_EVENT
2456 LOGGING(smtp_confirmation) &&
2461 const uschar *s = string_printing(buffer);
2462 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
2463 conf = (s == buffer)? (uschar *)string_copy(s) : US s;
2466 /* Process all transported addresses - for LMTP or PRDR, read a status for
2469 for (addr = addrlist; addr != first_addr; addr = addr->next)
2471 if (addr->transport_return != PENDING_OK) continue;
2473 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
2474 remaining addresses. Otherwise, it's a return code for just the one
2475 address. For temporary errors, add a retry item for the address so that
2476 it doesn't get tried again too soon. */
2478 #ifndef DISABLE_PRDR
2479 if (lmtp || prdr_active)
2484 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2487 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
2488 addr->message = string_sprintf(
2489 #ifndef DISABLE_PRDR
2490 "%s error after %s: %s", prdr_active ? "PRDR":"LMTP",
2492 "LMTP error after %s: %s",
2494 big_buffer, string_printing(buffer));
2495 setflag(addr, af_pass_message); /* Allow message to go to user */
2496 if (buffer[0] == '5')
2497 addr->transport_return = FAIL;
2500 errno = ERRNO_DATA4XX;
2501 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2502 addr->transport_return = DEFER;
2503 #ifndef DISABLE_PRDR
2506 retry_add_item(addr, addr->address_retry_key, 0);
2510 completed_address = TRUE; /* NOW we can set this flag */
2511 if (LOGGING(smtp_confirmation))
2513 const uschar *s = string_printing(buffer);
2514 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
2515 conf = (s == buffer)? (uschar *)string_copy(s) : US s;
2519 /* SMTP, or success return from LMTP for this address. Pass back the
2520 actual host that was used. */
2522 addr->transport_return = OK;
2523 addr->more_errno = delivery_time;
2524 addr->host_used = host;
2525 addr->special_action = flag;
2526 addr->message = conf;
2527 #ifndef DISABLE_PRDR
2528 if (prdr_active) addr->flags |= af_prdr_used;
2532 #ifndef DISABLE_PRDR
2536 /* Update the journal. For homonymic addresses, use the base address plus
2537 the transport name. See lots of comments in deliver.c about the reasons
2538 for the complications when homonyms are involved. Just carry on after
2539 write error, as it may prove possible to update the spool file later. */
2541 if (testflag(addr, af_homonym))
2542 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2544 sprintf(CS buffer, "%.500s\n", addr->unique);
2546 DEBUG(D_deliver) debug_printf("journalling %s\n", buffer);
2547 len = Ustrlen(CS buffer);
2548 if (write(journal_fd, buffer, len) != len)
2549 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2550 "%s: %s", buffer, strerror(errno));
2554 #ifndef DISABLE_PRDR
2557 /* PRDR - get the final, overall response. For any non-success
2558 upgrade all the address statuses. */
2559 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2563 if(errno == 0 && buffer[0] == '4')
2565 errno = ERRNO_DATA4XX;
2566 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2568 for (addr = addrlist; addr != first_addr; addr = addr->next)
2569 if (buffer[0] == '5' || addr->transport_return == OK)
2570 addr->transport_return = PENDING_OK; /* allow set_errno action */
2571 goto RESPONSE_FAILED;
2574 /* Update the journal, or setup retry. */
2575 for (addr = addrlist; addr != first_addr; addr = addr->next)
2576 if (addr->transport_return == OK)
2578 if (testflag(addr, af_homonym))
2579 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2581 sprintf(CS buffer, "%.500s\n", addr->unique);
2583 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s\n", buffer);
2584 len = Ustrlen(CS buffer);
2585 if (write(journal_fd, buffer, len) != len)
2586 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2587 "%s: %s", buffer, strerror(errno));
2589 else if (addr->transport_return == DEFER)
2590 retry_add_item(addr, addr->address_retry_key, -2);
2594 /* Ensure the journal file is pushed out to disk. */
2596 if (EXIMfsync(journal_fd) < 0)
2597 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
2603 /* Handle general (not specific to one address) failures here. The value of ok
2604 is used to skip over this code on the falling through case. A timeout causes a
2605 deferral. Other errors may defer or fail according to the response code, and
2606 may set up a special errno value, e.g. after connection chopped, which is
2607 assumed if errno == 0 and there is no text in the buffer. If control reaches
2608 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
2609 the problem is not related to this specific message. */
2614 uschar * set_message;
2620 send_quit = check_response(host, &save_errno, addrlist->more_errno,
2621 buffer, &code, &message, &pass_message);
2629 message = US string_sprintf("send() to %s [%s] failed: %s",
2630 host->name, host->address, strerror(save_errno));
2635 /* This label is jumped to directly when a TLS negotiation has failed,
2636 or was not done for a host for which it is required. Values will be set
2637 in message and save_errno, and setting_up will always be true. Treat as
2638 a temporary error. */
2645 /* If the failure happened while setting up the call, see if the failure was
2646 a 5xx response (this will either be on connection, or following HELO - a 5xx
2647 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
2648 never going to accept them. For other errors during setting up (timeouts or
2649 whatever), defer all addresses, and yield DEFER, so that the host is not
2650 tried again for a while. */
2653 ok = FALSE; /* For when reached by GOTO */
2654 set_message = message;
2661 yield = set_rc = DEFER;
2664 /* We want to handle timeouts after MAIL or "." and loss of connection after
2665 "." specially. They can indicate a problem with the sender address or with
2666 the contents of the message rather than a real error on the connection. These
2667 cases are treated in the same way as a 4xx response. This next bit of code
2668 does the classification. */
2677 case ERRNO_UTF8_FWD:
2684 message_error = TRUE;
2688 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
2689 Ustrncmp(smtp_command,"end ",4) == 0;
2692 case ERRNO_SMTPCLOSED:
2693 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
2697 message_error = FALSE;
2701 /* Handle the cases that are treated as message errors. These are:
2703 (a) negative response or timeout after MAIL
2704 (b) negative response after DATA
2705 (c) negative response or timeout or dropped connection after "."
2706 (d) utf8 support required and not offered
2708 It won't be a negative response or timeout after RCPT, as that is dealt
2709 with separately above. The action in all cases is to set an appropriate
2710 error code for all the addresses, but to leave yield set to OK because the
2711 host itself has not failed. Of course, it might in practice have failed
2712 when we've had a timeout, but if so, we'll discover that at the next
2713 delivery attempt. For a temporary error, set the message_defer flag, and
2714 write to the logs for information if this is not the last host. The error
2715 for the last host will be logged as part of the address's log line. */
2719 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
2721 /* If there's an errno, the message contains just the identity of
2726 else /* Anything other than 5 is treated as temporary */
2730 message = US string_sprintf("%s: %s", message, strerror(save_errno));
2731 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
2732 msglog_line(host, message);
2733 *message_defer = TRUE;
2737 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
2738 ".", or some other transportation error. We defer all addresses and yield
2739 DEFER, except for the case of failed add_headers expansion, or a transport
2740 filter failure, when the yield should be ERROR, to stop it trying other
2746 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
2747 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
2751 set_errno(addrlist, save_errno, set_message, set_rc, pass_message, host
2752 #ifdef EXPERIMENTAL_DSN_INFO
2753 , smtp_greeting, helo_response
2759 /* If all has gone well, send_quit will be set TRUE, implying we can end the
2760 SMTP session tidily. However, if there were too many addresses to send in one
2761 message (indicated by first_addr being non-NULL) we want to carry on with the
2762 rest of them. Also, it is desirable to send more than one message down the SMTP
2763 connection if there are several waiting, provided we haven't already sent so
2764 many as to hit the configured limit. The function transport_check_waiting looks
2765 for a waiting message and returns its id. Then transport_pass_socket tries to
2766 set up a continued delivery by passing the socket on to another process. The
2767 variable send_rset is FALSE if a message has just been successfully transfered.
2769 If we are already sending down a continued channel, there may be further
2770 addresses not yet delivered that are aimed at the same host, but which have not
2771 been passed in this run of the transport. In this case, continue_more will be
2772 true, and all we should do is send RSET if necessary, and return, leaving the
2775 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
2776 do not want to continue with other messages down the same channel, because that
2777 can lead to looping between two or more messages, all with the same,
2778 temporarily failing address(es). [The retry information isn't updated yet, so
2779 new processes keep on trying.] We probably also don't want to try more of this
2780 message's addresses either.
2782 If we have started a TLS session, we have to end it before passing the
2783 connection to a new process. However, not all servers can handle this (Exim
2784 can), so we do not pass such a connection on if the host matches
2785 hosts_nopass_tls. */
2788 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
2789 "yield=%d first_address is %sNULL\n", ok, send_quit, send_rset,
2790 continue_more, yield, (first_addr == NULL)? "":"not ");
2792 if (completed_address && ok && send_quit)
2795 smtp_compare_t t_compare;
2797 t_compare.tblock = tblock;
2798 t_compare.current_sender_address = sender_address;
2800 if ( first_addr != NULL
2802 || ( ( tls_out.active < 0
2803 || verify_check_given_host(&ob->hosts_nopass_tls, host) != OK
2806 transport_check_waiting(tblock->name, host->name,
2807 tblock->connection_max_messages, new_message_id, &more,
2808 (oicf)smtp_are_same_identities, (void*)&t_compare)
2816 if (! (ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
2818 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
2819 host->address, strerror(save_errno));
2822 else if (! (ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2823 ob->command_timeout)))
2826 send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
2830 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
2831 host->name, host->address, msg);
2836 /* Either RSET was not needed, or it succeeded */
2840 if (first_addr != NULL) /* More addresses still to be sent */
2841 { /* in this run of the transport */
2842 continue_sequence++; /* Causes * in logging */
2845 if (continue_more) return yield; /* More addresses for another run */
2847 /* Pass the socket to a new Exim process. Before doing so, we must shut
2848 down TLS. Not all MTAs allow for the continuation of the SMTP session
2849 when TLS is shut down. We test for this by sending a new EHLO. If we
2850 don't get a good response, we don't attempt to pass the socket on. */
2853 if (tls_out.active >= 0)
2855 tls_close(FALSE, TRUE);
2859 ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
2860 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2861 ob->command_timeout);
2865 /* If the socket is successfully passed, we musn't send QUIT (or
2866 indeed anything!) from here. */
2868 /*XXX DSN_INFO: assume likely to do new HELO; but for greet we'll want to
2869 propagate it from the initial
2871 if (ok && transport_pass_socket(tblock->name, host->name, host->address,
2872 new_message_id, inblock.sock))
2878 /* If RSET failed and there are addresses left, they get deferred. */
2880 else set_errno(first_addr, errno, msg, DEFER, FALSE, host
2881 #ifdef EXPERIMENTAL_DSN_INFO
2882 , smtp_greeting, helo_response
2888 /* End off tidily with QUIT unless the connection has died or the socket has
2889 been passed to another process. There has been discussion on the net about what
2890 to do after sending QUIT. The wording of the RFC suggests that it is necessary
2891 to wait for a response, but on the other hand, there isn't anything one can do
2892 with an error response, other than log it. Exim used to do that. However,
2893 further discussion suggested that it is positively advantageous not to wait for
2894 the response, but to close the session immediately. This is supposed to move
2895 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
2896 load from the server. (Hosts that are both servers and clients may not see much
2897 difference, of course.) Further discussion indicated that this was safe to do
2898 on Unix systems which have decent implementations of TCP/IP that leave the
2899 connection around for a while (TIME_WAIT) after the application has gone away.
2900 This enables the response sent by the server to be properly ACKed rather than
2901 timed out, as can happen on broken TCP/IP implementations on other OS.
2903 This change is being made on 31-Jul-98. After over a year of trouble-free
2904 operation, the old commented-out code was removed on 17-Sep-99. */
2907 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2912 tls_close(FALSE, TRUE);
2915 /* Close the socket, and return the appropriate value, first setting
2916 works because the NULL setting is passed back to the calling process, and
2917 remote_max_parallel is forced to 1 when delivering over an existing connection,
2919 If all went well and continue_more is set, we shouldn't actually get here if
2920 there are further addresses, as the return above will be taken. However,
2921 writing RSET might have failed, or there may be other addresses whose hosts are
2922 specified in the transports, and therefore not visible at top level, in which
2923 case continue_more won't get set. */
2925 HDEBUG(D_transport|D_acl|D_v) debug_printf(" SMTP(close)>>\n");
2926 (void)close(inblock.sock);
2928 #ifndef DISABLE_EVENT
2929 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
2932 continue_transport = NULL;
2933 continue_hostname = NULL;
2940 /*************************************************
2941 * Closedown entry point *
2942 *************************************************/
2944 /* This function is called when exim is passed an open smtp channel
2945 from another incarnation, but the message which it has been asked
2946 to deliver no longer exists. The channel is on stdin.
2948 We might do fancy things like looking for another message to send down
2949 the channel, but if the one we sought has gone, it has probably been
2950 delivered by some other process that itself will seek further messages,
2951 so just close down our connection.
2953 Argument: pointer to the transport instance block
2958 smtp_transport_closedown(transport_instance *tblock)
2960 smtp_transport_options_block *ob =
2961 (smtp_transport_options_block *)(tblock->options_block);
2962 smtp_inblock inblock;
2963 smtp_outblock outblock;
2965 uschar inbuffer[4096];
2966 uschar outbuffer[16];
2968 inblock.sock = fileno(stdin);
2969 inblock.buffer = inbuffer;
2970 inblock.buffersize = sizeof(inbuffer);
2971 inblock.ptr = inbuffer;
2972 inblock.ptrend = inbuffer;
2974 outblock.sock = inblock.sock;
2975 outblock.buffersize = sizeof(outbuffer);
2976 outblock.buffer = outbuffer;
2977 outblock.ptr = outbuffer;
2978 outblock.cmd_count = 0;
2979 outblock.authenticating = FALSE;
2981 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2982 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2983 ob->command_timeout);
2984 (void)close(inblock.sock);
2989 /*************************************************
2990 * Prepare addresses for delivery *
2991 *************************************************/
2993 /* This function is called to flush out error settings from previous delivery
2994 attempts to other hosts. It also records whether we got here via an MX record
2995 or not in the more_errno field of the address. We are interested only in
2996 addresses that are still marked DEFER - others may have got delivered to a
2997 previously considered IP address. Set their status to PENDING_DEFER to indicate
2998 which ones are relevant this time.
3001 addrlist the list of addresses
3002 host the host we are delivering to
3004 Returns: the first address for this delivery
3007 static address_item *
3008 prepare_addresses(address_item *addrlist, host_item *host)
3010 address_item *first_addr = NULL;
3012 for (addr = addrlist; addr != NULL; addr = addr->next)
3013 if (addr->transport_return == DEFER)
3015 if (first_addr == NULL) first_addr = addr;
3016 addr->transport_return = PENDING_DEFER;
3017 addr->basic_errno = 0;
3018 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
3019 addr->message = NULL;
3021 addr->cipher = NULL;
3022 addr->ourcert = NULL;
3023 addr->peercert = NULL;
3024 addr->peerdn = NULL;
3025 addr->ocsp = OCSP_NOT_REQ;
3027 #ifdef EXPERIMENTAL_DSN_INFO
3028 addr->smtp_greeting = NULL;
3029 addr->helo_response = NULL;
3037 /*************************************************
3038 * Main entry point *
3039 *************************************************/
3041 /* See local README for interface details. As this is a remote transport, it is
3042 given a chain of addresses to be delivered in one connection, if possible. It
3043 always returns TRUE, indicating that each address has its own independent
3044 status set, except if there is a setting up problem, in which case it returns
3048 smtp_transport_entry(
3049 transport_instance *tblock, /* data for this instantiation */
3050 address_item *addrlist) /* addresses we are working on */
3054 int hosts_defer = 0;
3056 int hosts_looked_up = 0;
3057 int hosts_retry = 0;
3058 int hosts_serial = 0;
3059 int hosts_total = 0;
3060 int total_hosts_tried = 0;
3062 BOOL expired = TRUE;
3063 BOOL continuing = continue_hostname != NULL;
3064 uschar *expanded_hosts = NULL;
3066 uschar *tid = string_sprintf("%s transport", tblock->name);
3067 smtp_transport_options_block *ob =
3068 (smtp_transport_options_block *)(tblock->options_block);
3069 host_item *hostlist = addrlist->host_list;
3070 host_item *host = NULL;
3074 debug_printf("%s transport entered\n", tblock->name);
3075 for (addr = addrlist; addr != NULL; addr = addr->next)
3076 debug_printf(" %s\n", addr->address);
3077 if (continuing) debug_printf("already connected to %s [%s]\n",
3078 continue_hostname, continue_host_address);
3081 /* Set the flag requesting that these hosts be added to the waiting
3082 database if the delivery fails temporarily or if we are running with
3083 queue_smtp or a 2-stage queue run. This gets unset for certain
3084 kinds of error, typically those that are specific to the message. */
3086 update_waiting = TRUE;
3088 /* If a host list is not defined for the addresses - they must all have the
3089 same one in order to be passed to a single transport - or if the transport has
3090 a host list with hosts_override set, use the host list supplied with the
3091 transport. It is an error for this not to exist. */
3093 if (hostlist == NULL || (ob->hosts_override && ob->hosts != NULL))
3095 if (ob->hosts == NULL)
3097 addrlist->message = string_sprintf("%s transport called with no hosts set",
3099 addrlist->transport_return = PANIC;
3100 return FALSE; /* Only top address has status */
3103 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
3106 /* If the transport's host list contains no '$' characters, and we are not
3107 randomizing, it is fixed and therefore a chain of hosts can be built once
3108 and for all, and remembered for subsequent use by other calls to this
3109 transport. If, on the other hand, the host list does contain '$', or we are
3110 randomizing its order, we have to rebuild it each time. In the fixed case,
3111 as the hosts string will never be used again, it doesn't matter that we
3112 replace all the : characters with zeros. */
3114 if (ob->hostlist == NULL)
3116 uschar *s = ob->hosts;
3118 if (Ustrchr(s, '$') != NULL)
3120 if (!(expanded_hosts = expand_string(s)))
3122 addrlist->message = string_sprintf("failed to expand list of hosts "
3123 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
3124 addrlist->transport_return = search_find_defer? DEFER : PANIC;
3125 return FALSE; /* Only top address has status */
3127 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
3128 "\"%s\"\n", s, expanded_hosts);
3132 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
3134 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
3136 /* Check that the expansion yielded something useful. */
3137 if (hostlist == NULL)
3140 string_sprintf("%s transport has empty hosts setting", tblock->name);
3141 addrlist->transport_return = PANIC;
3142 return FALSE; /* Only top address has status */
3145 /* If there was no expansion of hosts, save the host list for
3148 if (!expanded_hosts) ob->hostlist = hostlist;
3151 /* This is not the first time this transport has been run in this delivery;
3152 the host list was built previously. */
3155 hostlist = ob->hostlist;
3158 /* The host list was supplied with the address. If hosts_randomize is set, we
3159 must sort it into a random order if it did not come from MX records and has not
3160 already been randomized (but don't bother if continuing down an existing
3163 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continuing)
3165 host_item *newlist = NULL;
3166 while (hostlist != NULL)
3168 host_item *h = hostlist;
3169 hostlist = hostlist->next;
3171 h->sort_key = random_number(100);
3173 if (newlist == NULL)
3178 else if (h->sort_key < newlist->sort_key)
3185 host_item *hh = newlist;
3186 while (hh->next != NULL)
3188 if (h->sort_key < hh->next->sort_key) break;
3196 hostlist = addrlist->host_list = newlist;
3199 /* Sort out the default port. */
3201 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
3203 /* For each host-plus-IP-address on the list:
3205 . If this is a continued delivery and the host isn't the one with the
3206 current connection, skip.
3208 . If the status is unusable (i.e. previously failed or retry checked), skip.
3210 . If no IP address set, get the address, either by turning the name into
3211 an address, calling gethostbyname if gethostbyname is on, or by calling
3212 the DNS. The DNS may yield multiple addresses, in which case insert the
3213 extra ones into the list.
3215 . Get the retry data if not previously obtained for this address and set the
3216 field which remembers the state of this address. Skip if the retry time is
3217 not reached. If not, remember whether retry data was found. The retry string
3218 contains both the name and the IP address.
3220 . Scan the list of addresses and mark those whose status is DEFER as
3221 PENDING_DEFER. These are the only ones that will be processed in this cycle
3224 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
3225 Some addresses may be successfully delivered, others may fail, and yet
3226 others may get temporary errors and so get marked DEFER.
3228 . The return from the delivery attempt is OK if a connection was made and a
3229 valid SMTP dialogue was completed. Otherwise it is DEFER.
3231 . If OK, add a "remove" retry item for this host/IPaddress, if any.
3233 . If fail to connect, or other defer state, add a retry item.
3235 . If there are any addresses whose status is still DEFER, carry on to the
3236 next host/IPaddress, unless we have tried the number of hosts given
3237 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
3238 there is some fancy logic for hosts_max_try that means its limit can be
3239 overstepped in some circumstances.
3241 If we get to the end of the list, all hosts have deferred at least one address,
3242 or not reached their retry times. If delay_after_cutoff is unset, it requests a
3243 delivery attempt to those hosts whose last try was before the arrival time of
3244 the current message. To cope with this, we have to go round the loop a second
3245 time. After that, set the status and error data for any addresses that haven't
3246 had it set already. */
3248 for (cutoff_retry = 0; expired &&
3249 cutoff_retry < ((ob->delay_after_cutoff)? 1 : 2);
3252 host_item *nexthost = NULL;
3253 int unexpired_hosts_tried = 0;
3255 for (host = hostlist;
3257 unexpired_hosts_tried < ob->hosts_max_try &&
3258 total_hosts_tried < ob->hosts_max_try_hardlimit;
3264 BOOL serialized = FALSE;
3265 BOOL host_is_expired = FALSE;
3266 BOOL message_defer = FALSE;
3267 BOOL some_deferred = FALSE;
3268 address_item *first_addr = NULL;
3269 uschar *interface = NULL;
3270 uschar *retry_host_key = NULL;
3271 uschar *retry_message_key = NULL;
3272 uschar *serialize_key = NULL;
3274 /* Default next host is next host. :-) But this can vary if the
3275 hosts_max_try limit is hit (see below). It may also be reset if a host
3276 address is looked up here (in case the host was multihomed). */
3278 nexthost = host->next;
3280 /* If the address hasn't yet been obtained from the host name, look it up
3281 now, unless the host is already marked as unusable. If it is marked as
3282 unusable, it means that the router was unable to find its IP address (in
3283 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
3284 the lookup failed last time. We don't get this far if *all* MX records
3285 point to non-existent hosts; that is treated as a hard error.
3287 We can just skip this host entirely. When the hosts came from the router,
3288 the address will timeout based on the other host(s); when the address is
3289 looked up below, there is an explicit retry record added.
3291 Note that we mustn't skip unusable hosts if the address is not unset; they
3292 may be needed as expired hosts on the 2nd time round the cutoff loop. */
3294 if (host->address == NULL)
3296 int new_port, flags;
3299 if (host->status >= hstatus_unusable)
3301 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
3306 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
3308 /* The host name is permitted to have an attached port. Find it, and
3309 strip it from the name. Just remember it for now. */
3311 new_port = host_item_get_port(host);
3313 /* Count hosts looked up */
3317 /* Find by name if so configured, or if it's an IP address. We don't
3318 just copy the IP address, because we need the test-for-local to happen. */
3320 flags = HOST_FIND_BY_A;
3321 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
3322 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
3324 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
3325 rc = host_find_byname(host, NULL, flags, NULL, TRUE);
3327 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
3328 &ob->dnssec, /* domains for request/require */
3331 /* Update the host (and any additional blocks, resulting from
3332 multihoming) with a host-specific port, if any. */
3334 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
3336 /* Failure to find the host at this time (usually DNS temporary failure)
3337 is really a kind of routing failure rather than a transport failure.
3338 Therefore we add a retry item of the routing kind, not to stop us trying
3339 to look this name up here again, but to ensure the address gets timed
3340 out if the failures go on long enough. A complete failure at this point
3341 commonly points to a configuration error, but the best action is still
3342 to carry on for the next host. */
3344 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
3346 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
3348 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
3349 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
3350 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
3351 host->status = hstatus_unusable;
3353 for (addr = addrlist; addr != NULL; addr = addr->next)
3355 if (addr->transport_return != DEFER) continue;
3356 addr->basic_errno = ERRNO_UNKNOWNHOST;
3358 string_sprintf("failed to lookup IP address for %s", host->name);
3363 /* If the host is actually the local host, we may have a problem, or
3364 there may be some cunning configuration going on. In the problem case,
3365 log things and give up. The default transport status is already DEFER. */
3367 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
3369 for (addr = addrlist; addr != NULL; addr = addr->next)
3371 addr->basic_errno = 0;
3372 addr->message = string_sprintf("%s transport found host %s to be "
3373 "local", tblock->name, host->name);
3377 } /* End of block for IP address lookup */
3379 /* If this is a continued delivery, we are interested only in the host
3380 which matches the name of the existing open channel. The check is put
3381 here after the local host lookup, in case the name gets expanded as a
3382 result of the lookup. Set expired FALSE, to save the outer loop executing
3385 if (continuing && (Ustrcmp(continue_hostname, host->name) != 0 ||
3386 Ustrcmp(continue_host_address, host->address) != 0))
3389 continue; /* With next host */
3392 /* Reset the default next host in case a multihomed host whose addresses
3393 are not looked up till just above added to the host list. */
3395 nexthost = host->next;
3397 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
3398 domain is in queue_smtp_domains, we don't actually want to attempt any
3399 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
3400 there is a lookup defer in queue_smtp_domains, proceed as if the domain
3401 were not in it. We don't want to hold up all SMTP deliveries! Except when
3402 doing a two-stage queue run, don't do this if forcing. */
3404 if ((!deliver_force || queue_2stage) && (queue_smtp ||
3405 match_isinlist(addrlist->domain,
3406 (const uschar **)&queue_smtp_domains, 0,
3407 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
3410 for (addr = addrlist; addr != NULL; addr = addr->next)
3412 if (addr->transport_return != DEFER) continue;
3413 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
3415 continue; /* With next host */
3418 /* Count hosts being considered - purely for an intelligent comment
3419 if none are usable. */
3423 /* Set $host and $host address now in case they are needed for the
3424 interface expansion or the serialize_hosts check; they remain set if an
3425 actual delivery happens. */
3427 deliver_host = host->name;
3428 deliver_host_address = host->address;
3429 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
3430 : host->dnssec == DS_NO ? US"no"
3433 /* Set up a string for adding to the retry key if the port number is not
3434 the standard SMTP port. A host may have its own port setting that overrides
3437 pistring = string_sprintf(":%d", (host->port == PORT_NONE)?
3439 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
3441 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
3442 string is set, even if constant (as different transports can have different
3443 constant settings), we must add it to the key that is used for retries,
3444 because connections to the same host from a different interface should be
3445 treated separately. */
3447 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET : AF_INET6;
3448 if ((rs = ob->interface) && *rs)
3450 if (!smtp_get_interface(rs, host_af, addrlist, &interface, tid))
3452 pistring = string_sprintf("%s/%s", pistring, interface);
3455 /* The first time round the outer loop, check the status of the host by
3456 inspecting the retry data. The second time round, we are interested only
3457 in expired hosts that haven't been tried since this message arrived. */
3459 if (cutoff_retry == 0)
3462 /* Ensure the status of the address is set by checking retry data if
3463 necessary. There may be host-specific retry data (applicable to all
3464 messages) and also data for retries of a specific message at this host.
3465 If either of these retry records are actually read, the keys used are
3466 returned to save recomputing them later. */
3468 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3469 US"retry_include_ip_address", ob->retry_include_ip_address,
3470 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3471 continue; /* with next host */
3473 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
3474 incl_ip, &retry_host_key, &retry_message_key);
3476 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
3477 (host->address == NULL)? US"" : host->address, pistring,
3478 (host->status == hstatus_usable)? "usable" :
3479 (host->status == hstatus_unusable)? "unusable" :
3480 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
3482 /* Skip this address if not usable at this time, noting if it wasn't
3483 actually expired, both locally and in the address. */
3485 switch (host->status)
3487 case hstatus_unusable:
3489 setflag(addrlist, af_retry_skipped);
3492 case hstatus_unusable_expired:
3495 case hwhy_retry: hosts_retry++; break;
3496 case hwhy_failed: hosts_fail++; break;
3497 case hwhy_deferred: hosts_defer++; break;
3500 /* If there was a retry message key, implying that previously there
3501 was a message-specific defer, we don't want to update the list of
3502 messages waiting for these hosts. */
3504 if (retry_message_key != NULL) update_waiting = FALSE;
3505 continue; /* With the next host or IP address */
3509 /* Second time round the loop: if the address is set but expired, and
3510 the message is newer than the last try, let it through. */
3514 if (host->address == NULL ||
3515 host->status != hstatus_unusable_expired ||
3516 host->last_try > received_time)
3519 debug_printf("trying expired host %s [%s]%s\n",
3520 host->name, host->address, pistring);
3521 host_is_expired = TRUE;
3524 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
3525 it remains TRUE only if all hosts are expired and none are actually tried.
3530 /* If this host is listed as one to which access must be serialized,
3531 see if another Exim process has a connection to it, and if so, skip
3532 this host. If not, update the database to record our connection to it
3533 and remember this for later deletion. Do not do any of this if we are
3534 sending the message down a pre-existing connection. */
3537 verify_check_given_host(&ob->serialize_hosts, host) == OK)
3539 serialize_key = string_sprintf("host-serialize-%s", host->name);
3540 if (!enq_start(serialize_key, 1))
3543 debug_printf("skipping host %s because another Exim process "
3544 "is connected to it\n", host->name);
3551 /* OK, we have an IP address that is not waiting for its retry time to
3552 arrive (it might be expired) OR (second time round the loop) we have an
3553 expired host that hasn't been tried since the message arrived. Have a go
3554 at delivering the message to it. First prepare the addresses by flushing
3555 out the result of previous attempts, and finding the first address that
3556 is still to be delivered. */
3558 first_addr = prepare_addresses(addrlist, host);
3560 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
3561 message_id, host->name, host->address, addrlist->address,
3562 (addrlist->next == NULL)? "" : ", ...");
3564 set_process_info("delivering %s to %s [%s] (%s%s)",
3565 message_id, host->name, host->address, addrlist->address,
3566 (addrlist->next == NULL)? "" : ", ...");
3568 /* This is not for real; don't do the delivery. If there are
3569 any remaining hosts, list them. */
3574 set_errno_nohost(addrlist, 0, NULL, OK, FALSE);
3575 for (addr = addrlist; addr != NULL; addr = addr->next)
3577 addr->host_used = host;
3578 addr->special_action = '*';
3579 addr->message = US"delivery bypassed by -N option";
3583 debug_printf("*** delivery by %s transport bypassed by -N option\n"
3584 "*** host and remaining hosts:\n", tblock->name);
3585 for (host2 = host; host2 != NULL; host2 = host2->next)
3586 debug_printf(" %s [%s]\n", host2->name,
3587 (host2->address == NULL)? US"unset" : host2->address);
3592 /* This is for real. If the host is expired, we don't count it for
3593 hosts_max_retry. This ensures that all hosts must expire before an address
3594 is timed out, unless hosts_max_try_hardlimit (which protects against
3595 lunatic DNS configurations) is reached.
3597 If the host is not expired and we are about to hit the hosts_max_retry
3598 limit, check to see if there is a subsequent hosts with a different MX
3599 value. If so, make that the next host, and don't count this one. This is a
3600 heuristic to make sure that different MXs do get tried. With a normal kind
3601 of retry rule, they would get tried anyway when the earlier hosts were
3602 delayed, but if the domain has a "retry every time" type of rule - as is
3603 often used for the the very large ISPs, that won't happen. */
3608 /* Make a copy of the host if it is local to this invocation
3609 of the transport. */
3613 thost = store_get(sizeof(host_item));
3615 thost->name = string_copy(host->name);
3616 thost->address = string_copy(host->address);
3621 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
3625 debug_printf("hosts_max_try limit reached with this host\n");
3626 for (h = host; h; h = h->next) if (h->mx != host->mx)
3629 unexpired_hosts_tried--;
3630 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
3631 "and will be tried\n");
3636 /* Attempt the delivery. */
3638 total_hosts_tried++;
3639 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
3640 &message_defer, FALSE);
3643 OK => connection made, each address contains its result;
3644 message_defer is set for message-specific defers (when all
3645 recipients are marked defer)
3646 DEFER => there was a non-message-specific delivery problem;
3647 ERROR => there was a problem setting up the arguments for a filter,
3648 or there was a problem with expanding added headers
3651 /* If the result is not OK, there was a non-message-specific problem.
3652 If the result is DEFER, we need to write to the logs saying what happened
3653 for this particular host, except in the case of authentication and TLS
3654 failures, where the log has already been written. If all hosts defer a
3655 general message is written at the end. */
3657 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL &&
3658 first_addr->basic_errno != ERRNO_TLSFAILURE)
3659 write_logs(first_addr, host);
3661 #ifndef DISABLE_EVENT
3663 deferred_event_raise(first_addr, host);
3666 /* If STARTTLS was accepted, but there was a failure in setting up the
3667 TLS session (usually a certificate screwup), and the host is not in
3668 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
3669 TLS forcibly turned off. We have to start from scratch with a new SMTP
3670 connection. That's why the retry is done from here, not from within
3671 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
3672 session, so the in-clear transmission after those errors, if permitted,
3673 happens inside smtp_deliver().] */
3677 && first_addr->basic_errno == ERRNO_TLSFAILURE
3678 && ob->tls_tempfail_tryclear
3679 && verify_check_given_host(&ob->hosts_require_tls, host) != OK
3682 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
3683 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
3684 first_addr = prepare_addresses(addrlist, host);
3685 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
3686 &message_defer, TRUE);
3687 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
3688 write_logs(first_addr, host);
3689 # ifndef DISABLE_EVENT
3691 deferred_event_raise(first_addr, host);
3694 #endif /*SUPPORT_TLS*/
3697 /* Delivery attempt finished */
3699 rs = (rc == OK)? US"OK" : (rc == DEFER)? US"DEFER" : (rc == ERROR)?
3702 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
3703 message_id, host->name, host->address, addrlist->address,
3704 (addrlist->next == NULL)? "" : " (& others)", rs);
3706 /* Release serialization if set up */
3708 if (serialized) enq_end(serialize_key);
3710 /* If the result is DEFER, or if a host retry record is known to exist, we
3711 need to add an item to the retry chain for updating the retry database
3712 at the end of delivery. We only need to add the item to the top address,
3713 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
3714 for any other delivery attempts using the same address. (It is copied into
3715 the unusable tree at the outer level, so even if different address blocks
3716 contain the same address, it still won't get tried again.) */
3718 if (rc == DEFER || retry_host_key != NULL)
3720 int delete_flag = (rc != DEFER)? rf_delete : 0;
3721 if (retry_host_key == NULL)
3724 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3725 US"retry_include_ip_address", ob->retry_include_ip_address,
3726 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3727 incl_ip = TRUE; /* error; use most-specific retry record */
3729 retry_host_key = incl_ip ?
3730 string_sprintf("T:%S:%s%s", host->name, host->address, pistring) :
3731 string_sprintf("T:%S%s", host->name, pistring);
3734 /* If a delivery of another message over an existing SMTP connection
3735 yields DEFER, we do NOT set up retry data for the host. This covers the
3736 case when there are delays in routing the addresses in the second message
3737 that are so long that the server times out. This is alleviated by not
3738 routing addresses that previously had routing defers when handling an
3739 existing connection, but even so, this case may occur (e.g. if a
3740 previously happily routed address starts giving routing defers). If the
3741 host is genuinely down, another non-continued message delivery will
3742 notice it soon enough. */
3744 if (delete_flag != 0 || !continuing)
3745 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
3747 /* We may have tried an expired host, if its retry time has come; ensure
3748 the status reflects the expiry for the benefit of any other addresses. */
3752 host->status = (host_is_expired)?
3753 hstatus_unusable_expired : hstatus_unusable;
3754 host->why = hwhy_deferred;
3758 /* If message_defer is set (host was OK, but every recipient got deferred
3759 because of some message-specific problem), or if that had happened
3760 previously so that a message retry key exists, add an appropriate item
3761 to the retry chain. Note that if there was a message defer but now there is
3762 a host defer, the message defer record gets deleted. That seems perfectly
3763 reasonable. Also, stop the message from being remembered as waiting
3764 for specific hosts. */
3766 if (message_defer || retry_message_key != NULL)
3768 int delete_flag = message_defer? 0 : rf_delete;
3769 if (retry_message_key == NULL)
3772 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3773 US"retry_include_ip_address", ob->retry_include_ip_address,
3774 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3775 incl_ip = TRUE; /* error; use most-specific retry record */
3777 retry_message_key = incl_ip ?
3778 string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
3780 string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
3782 retry_add_item(addrlist, retry_message_key,
3783 rf_message | rf_host | delete_flag);
3784 update_waiting = FALSE;
3787 /* Any return other than DEFER (that is, OK or ERROR) means that the
3788 addresses have got their final statuses filled in for this host. In the OK
3789 case, see if any of them are deferred. */
3792 for (addr = addrlist; addr; addr = addr->next)
3793 if (addr->transport_return == DEFER)
3795 some_deferred = TRUE;
3799 /* If no addresses deferred or the result was ERROR, return. We do this for
3800 ERROR because a failing filter set-up or add_headers expansion is likely to
3801 fail for any host we try. */
3803 if (rc == ERROR || (rc == OK && !some_deferred))
3805 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3806 return TRUE; /* Each address has its status */
3809 /* If the result was DEFER or some individual addresses deferred, let
3810 the loop run to try other hosts with the deferred addresses, except for the
3811 case when we were trying to deliver down an existing channel and failed.
3812 Don't try any other hosts in this case. */
3814 if (continuing) break;
3816 /* If the whole delivery, or some individual addresses, were deferred and
3817 there are more hosts that could be tried, do not count this host towards
3818 the hosts_max_try limit if the age of the message is greater than the
3819 maximum retry time for this host. This means we may try try all hosts,
3820 ignoring the limit, when messages have been around for some time. This is
3821 important because if we don't try all hosts, the address will never time
3822 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
3824 if ((rc == DEFER || some_deferred) && nexthost != NULL)
3827 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
3829 if (retry != NULL && retry->rules != NULL)
3831 retry_rule *last_rule;
3832 for (last_rule = retry->rules;
3833 last_rule->next != NULL;
3834 last_rule = last_rule->next);
3835 timedout = time(NULL) - received_time > last_rule->timeout;
3837 else timedout = TRUE; /* No rule => timed out */
3841 unexpired_hosts_tried--;
3842 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
3843 "hosts_max_try (message older than host's retry time)\n");
3846 } /* End of loop for trying multiple hosts. */
3848 /* This is the end of the loop that repeats iff expired is TRUE and
3849 ob->delay_after_cutoff is FALSE. The second time round we will
3850 try those hosts that haven't been tried since the message arrived. */
3854 debug_printf("all IP addresses skipped or deferred at least one address\n");
3855 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
3856 debug_printf("retrying IP addresses not tried since message arrived\n");
3861 /* Get here if all IP addresses are skipped or defer at least one address. In
3862 MUA wrapper mode, this will happen only for connection or other non-message-
3863 specific failures. Force the delivery status for all addresses to FAIL. */
3867 for (addr = addrlist; addr != NULL; addr = addr->next)
3868 addr->transport_return = FAIL;
3872 /* In the normal, non-wrapper case, add a standard message to each deferred
3873 address if there hasn't been an error, that is, if it hasn't actually been
3874 tried this time. The variable "expired" will be FALSE if any deliveries were
3875 actually tried, or if there was at least one host that was not expired. That
3876 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
3877 a delivery has been tried, an error code will be set, and the failing of the
3878 message is handled by the retry code later.
3880 If queue_smtp is set, or this transport was called to send a subsequent message
3881 down an existing TCP/IP connection, and something caused the host not to be
3882 found, we end up here, but can detect these cases and handle them specially. */
3884 for (addr = addrlist; addr; addr = addr->next)
3886 /* If host is not NULL, it means that we stopped processing the host list
3887 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
3888 means we need to behave as if some hosts were skipped because their retry
3889 time had not come. Specifically, this prevents the address from timing out.
3890 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
3891 hosts were tried. */
3894 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
3897 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
3898 "hosts were tried\n");
3903 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
3904 setflag(addr, af_retry_skipped);
3907 if (queue_smtp) /* no deliveries attempted */
3909 addr->transport_return = DEFER;
3910 addr->basic_errno = 0;
3911 addr->message = US"SMTP delivery explicitly queued";
3914 else if ( addr->transport_return == DEFER
3915 && (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0)
3919 addr->basic_errno = ERRNO_HRETRY;
3920 if (continue_hostname)
3921 addr->message = US"no host found for existing SMTP connection";
3924 setflag(addr, af_pass_message); /* This is not a security risk */
3925 addr->message = string_sprintf(
3926 "all hosts%s have been failing for a long time %s",
3927 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"",
3928 ob->delay_after_cutoff
3929 ? US"(and retry time not reached)"
3930 : US"and were last tried after this message arrived");
3932 /* If we are already using fallback hosts, or there are no fallback hosts
3933 defined, convert the result to FAIL to cause a bounce. */
3935 if (addr->host_list == addr->fallback_hosts || !addr->fallback_hosts)
3936 addr->transport_return = FAIL;
3941 if (hosts_retry == hosts_total)
3942 s = "retry time not reached for any host%s";
3943 else if (hosts_fail == hosts_total)
3944 s = "all host address lookups%s failed permanently";
3945 else if (hosts_defer == hosts_total)
3946 s = "all host address lookups%s failed temporarily";
3947 else if (hosts_serial == hosts_total)
3948 s = "connection limit reached for all hosts%s";
3949 else if (hosts_fail+hosts_defer == hosts_total)
3950 s = "all host address lookups%s failed";
3952 s = "some host address lookups failed and retry time "
3953 "not reached for other hosts or connection limit reached%s";
3955 addr->message = string_sprintf(s,
3956 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"");
3961 /* Update the database which keeps information about which messages are waiting
3962 for which hosts to become available. For some message-specific errors, the
3963 update_waiting flag is turned off because we don't want follow-on deliveries in
3964 those cases. If this transport instance is explicitly limited to one message
3965 per connection then follow-on deliveries are not possible and there's no need
3966 to create/update the per-transport wait-<transport_name> database. */
3968 if (update_waiting && tblock->connection_max_messages != 1)
3969 transport_update_waiting(hostlist, tblock->name);
3973 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3975 return TRUE; /* Each address has its status */
3980 /* End of transport/smtp.c */