1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2014 */
6 /* See the file NOTICE for conditions of use and distribution. */
12 #define PENDING_DEFER (PENDING + DEFER)
13 #define PENDING_OK (PENDING + OK)
16 /* Options specific to the smtp transport. This transport also supports LMTP
17 over TCP/IP. The options must be in alphabetic order (note that "_" comes
18 before the lower case letters). Some live in the transport_instance block so as
19 to be publicly visible; these are flagged with opt_public. */
21 optionlist smtp_transport_options[] = {
22 { "*expand_retry_include_ip_address", opt_stringptr | opt_hidden,
23 (void *)(offsetof(smtp_transport_options_block, expand_retry_include_ip_address)) },
25 { "address_retry_include_sender", opt_bool,
26 (void *)offsetof(smtp_transport_options_block, address_retry_include_sender) },
27 { "allow_localhost", opt_bool,
28 (void *)offsetof(smtp_transport_options_block, allow_localhost) },
29 { "authenticated_sender", opt_stringptr,
30 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
31 { "authenticated_sender_force", opt_bool,
32 (void *)offsetof(smtp_transport_options_block, authenticated_sender_force) },
33 { "command_timeout", opt_time,
34 (void *)offsetof(smtp_transport_options_block, command_timeout) },
35 { "connect_timeout", opt_time,
36 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
37 { "connection_max_messages", opt_int | opt_public,
38 (void *)offsetof(transport_instance, connection_max_messages) },
39 { "data_timeout", opt_time,
40 (void *)offsetof(smtp_transport_options_block, data_timeout) },
41 { "delay_after_cutoff", opt_bool,
42 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
44 { "dkim_canon", opt_stringptr,
45 (void *)offsetof(smtp_transport_options_block, dkim_canon) },
46 { "dkim_domain", opt_stringptr,
47 (void *)offsetof(smtp_transport_options_block, dkim_domain) },
48 { "dkim_private_key", opt_stringptr,
49 (void *)offsetof(smtp_transport_options_block, dkim_private_key) },
50 { "dkim_selector", opt_stringptr,
51 (void *)offsetof(smtp_transport_options_block, dkim_selector) },
52 { "dkim_sign_headers", opt_stringptr,
53 (void *)offsetof(smtp_transport_options_block, dkim_sign_headers) },
54 { "dkim_strict", opt_stringptr,
55 (void *)offsetof(smtp_transport_options_block, dkim_strict) },
57 { "dns_qualify_single", opt_bool,
58 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
59 { "dns_search_parents", opt_bool,
60 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
61 { "dnssec_request_domains", opt_stringptr,
62 (void *)offsetof(smtp_transport_options_block, dnssec_request_domains) },
63 { "dnssec_require_domains", opt_stringptr,
64 (void *)offsetof(smtp_transport_options_block, dnssec_require_domains) },
65 { "dscp", opt_stringptr,
66 (void *)offsetof(smtp_transport_options_block, dscp) },
67 { "fallback_hosts", opt_stringptr,
68 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
69 { "final_timeout", opt_time,
70 (void *)offsetof(smtp_transport_options_block, final_timeout) },
71 { "gethostbyname", opt_bool,
72 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
74 /* These are no longer honoured, as of Exim 4.80; for now, we silently
75 ignore; 4.83 will warn, and a later-still release will remove
76 these options, so that using them becomes an error. */
77 { "gnutls_require_kx", opt_stringptr,
78 (void *)offsetof(smtp_transport_options_block, gnutls_require_kx) },
79 { "gnutls_require_mac", opt_stringptr,
80 (void *)offsetof(smtp_transport_options_block, gnutls_require_mac) },
81 { "gnutls_require_protocols", opt_stringptr,
82 (void *)offsetof(smtp_transport_options_block, gnutls_require_proto) },
84 { "helo_data", opt_stringptr,
85 (void *)offsetof(smtp_transport_options_block, helo_data) },
86 { "hosts", opt_stringptr,
87 (void *)offsetof(smtp_transport_options_block, hosts) },
88 { "hosts_avoid_esmtp", opt_stringptr,
89 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
90 { "hosts_avoid_pipelining", opt_stringptr,
91 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
93 { "hosts_avoid_tls", opt_stringptr,
94 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
96 { "hosts_max_try", opt_int,
97 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
98 { "hosts_max_try_hardlimit", opt_int,
99 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
101 { "hosts_nopass_tls", opt_stringptr,
102 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
104 { "hosts_override", opt_bool,
105 (void *)offsetof(smtp_transport_options_block, hosts_override) },
106 { "hosts_randomize", opt_bool,
107 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
108 #if defined(SUPPORT_TLS) && !defined(DISABLE_OCSP)
109 { "hosts_request_ocsp", opt_stringptr,
110 (void *)offsetof(smtp_transport_options_block, hosts_request_ocsp) },
112 { "hosts_require_auth", opt_stringptr,
113 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
115 # ifdef EXPERIMENTAL_DANE
116 { "hosts_require_dane", opt_stringptr,
117 (void *)offsetof(smtp_transport_options_block, hosts_require_dane) },
119 # ifndef DISABLE_OCSP
120 { "hosts_require_ocsp", opt_stringptr,
121 (void *)offsetof(smtp_transport_options_block, hosts_require_ocsp) },
123 { "hosts_require_tls", opt_stringptr,
124 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
126 { "hosts_try_auth", opt_stringptr,
127 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
128 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
129 { "hosts_try_dane", opt_stringptr,
130 (void *)offsetof(smtp_transport_options_block, hosts_try_dane) },
133 { "hosts_try_prdr", opt_stringptr,
134 (void *)offsetof(smtp_transport_options_block, hosts_try_prdr) },
137 { "hosts_verify_avoid_tls", opt_stringptr,
138 (void *)offsetof(smtp_transport_options_block, hosts_verify_avoid_tls) },
140 { "interface", opt_stringptr,
141 (void *)offsetof(smtp_transport_options_block, interface) },
142 { "keepalive", opt_bool,
143 (void *)offsetof(smtp_transport_options_block, keepalive) },
144 { "lmtp_ignore_quota", opt_bool,
145 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
146 { "max_rcpt", opt_int | opt_public,
147 (void *)offsetof(transport_instance, max_addresses) },
148 { "multi_domain", opt_bool | opt_public,
149 (void *)offsetof(transport_instance, multi_domain) },
150 { "port", opt_stringptr,
151 (void *)offsetof(smtp_transport_options_block, port) },
152 { "protocol", opt_stringptr,
153 (void *)offsetof(smtp_transport_options_block, protocol) },
154 { "retry_include_ip_address", opt_expand_bool,
155 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
156 { "serialize_hosts", opt_stringptr,
157 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
158 { "size_addition", opt_int,
159 (void *)offsetof(smtp_transport_options_block, size_addition) }
161 ,{ "tls_certificate", opt_stringptr,
162 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
163 { "tls_crl", opt_stringptr,
164 (void *)offsetof(smtp_transport_options_block, tls_crl) },
165 { "tls_dh_min_bits", opt_int,
166 (void *)offsetof(smtp_transport_options_block, tls_dh_min_bits) },
167 { "tls_privatekey", opt_stringptr,
168 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
169 { "tls_require_ciphers", opt_stringptr,
170 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
171 { "tls_sni", opt_stringptr,
172 (void *)offsetof(smtp_transport_options_block, tls_sni) },
173 { "tls_tempfail_tryclear", opt_bool,
174 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
175 { "tls_try_verify_hosts", opt_stringptr,
176 (void *)offsetof(smtp_transport_options_block, tls_try_verify_hosts) },
177 #ifdef EXPERIMENTAL_CERTNAMES
178 { "tls_verify_cert_hostnames", opt_stringptr,
179 (void *)offsetof(smtp_transport_options_block,tls_verify_cert_hostnames)},
181 { "tls_verify_certificates", opt_stringptr,
182 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) },
183 { "tls_verify_hosts", opt_stringptr,
184 (void *)offsetof(smtp_transport_options_block, tls_verify_hosts) }
188 /* Size of the options list. An extern variable has to be used so that its
189 address can appear in the tables drtables.c. */
191 int smtp_transport_options_count =
192 sizeof(smtp_transport_options)/sizeof(optionlist);
194 /* Default private options block for the smtp transport. */
196 smtp_transport_options_block smtp_transport_option_defaults = {
198 NULL, /* fallback_hosts */
200 NULL, /* fallback_hostlist */
201 NULL, /* authenticated_sender */
202 US"$primary_hostname", /* helo_data */
203 NULL, /* interface */
205 US"smtp", /* protocol */
207 NULL, /* serialize_hosts */
208 NULL, /* hosts_try_auth */
209 NULL, /* hosts_require_auth */
210 #ifdef EXPERIMENTAL_DANE
211 NULL, /* hosts_try_dane */
212 NULL, /* hosts_require_dane */
215 NULL, /* hosts_try_prdr */
218 US"*", /* hosts_request_ocsp (except under DANE; tls_client_start()) */
219 NULL, /* hosts_require_ocsp */
221 NULL, /* hosts_require_tls */
222 NULL, /* hosts_avoid_tls */
223 US"*", /* hosts_verify_avoid_tls */
224 NULL, /* hosts_avoid_pipelining */
225 NULL, /* hosts_avoid_esmtp */
226 NULL, /* hosts_nopass_tls */
227 5*60, /* command_timeout */
228 5*60, /* connect_timeout; shorter system default overrides */
229 5*60, /* data timeout */
230 10*60, /* final timeout */
231 1024, /* size_addition */
232 5, /* hosts_max_try */
233 50, /* hosts_max_try_hardlimit */
234 TRUE, /* address_retry_include_sender */
235 FALSE, /* allow_localhost */
236 FALSE, /* authenticated_sender_force */
237 FALSE, /* gethostbyname */
238 TRUE, /* dns_qualify_single */
239 FALSE, /* dns_search_parents */
240 NULL, /* dnssec_request_domains */
241 NULL, /* dnssec_require_domains */
242 TRUE, /* delay_after_cutoff */
243 FALSE, /* hosts_override */
244 FALSE, /* hosts_randomize */
245 TRUE, /* keepalive */
246 FALSE, /* lmtp_ignore_quota */
247 NULL, /* expand_retry_include_ip_address */
248 TRUE /* retry_include_ip_address */
250 ,NULL, /* tls_certificate */
252 NULL, /* tls_privatekey */
253 NULL, /* tls_require_ciphers */
254 NULL, /* gnutls_require_kx */
255 NULL, /* gnutls_require_mac */
256 NULL, /* gnutls_require_proto */
258 NULL, /* tls_verify_certificates */
259 EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
260 /* tls_dh_min_bits */
261 TRUE, /* tls_tempfail_tryclear */
262 NULL, /* tls_verify_hosts */
263 NULL /* tls_try_verify_hosts */
264 # ifdef EXPERIMENTAL_CERTNAMES
265 ,NULL /* tls_verify_cert_hostnames */
269 ,NULL, /* dkim_canon */
270 NULL, /* dkim_domain */
271 NULL, /* dkim_private_key */
272 NULL, /* dkim_selector */
273 NULL, /* dkim_sign_headers */
274 NULL /* dkim_strict */
278 #ifdef EXPERIMENTAL_DSN
279 /* some DSN flags for use later */
281 static int rf_list[] = {rf_notify_never, rf_notify_success,
282 rf_notify_failure, rf_notify_delay };
284 static uschar *rf_names[] = { US"NEVER", US"SUCCESS", US"FAILURE", US"DELAY" };
291 static uschar *smtp_command; /* Points to last cmd for error messages */
292 static uschar *mail_command; /* Points to MAIL cmd for error messages */
293 static BOOL update_waiting; /* TRUE to update the "wait" database */
296 /*************************************************
297 * Setup entry point *
298 *************************************************/
300 /* This function is called when the transport is about to be used,
301 but before running it in a sub-process. It is used for two things:
303 (1) To set the fallback host list in addresses, when delivering.
304 (2) To pass back the interface, port, protocol, and other options, for use
305 during callout verification.
308 tblock pointer to the transport instance block
309 addrlist list of addresses about to be transported
310 tf if not NULL, pointer to block in which to return options
311 uid the uid that will be set (not used)
312 gid the gid that will be set (not used)
313 errmsg place for error message (not used)
315 Returns: OK always (FAIL, DEFER not used)
319 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
320 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
322 smtp_transport_options_block *ob =
323 (smtp_transport_options_block *)(tblock->options_block);
325 errmsg = errmsg; /* Keep picky compilers happy */
329 /* Pass back options if required. This interface is getting very messy. */
333 tf->interface = ob->interface;
335 tf->protocol = ob->protocol;
336 tf->hosts = ob->hosts;
337 tf->hosts_override = ob->hosts_override;
338 tf->hosts_randomize = ob->hosts_randomize;
339 tf->gethostbyname = ob->gethostbyname;
340 tf->qualify_single = ob->dns_qualify_single;
341 tf->search_parents = ob->dns_search_parents;
342 tf->helo_data = ob->helo_data;
345 /* Set the fallback host list for all the addresses that don't have fallback
346 host lists, provided that the local host wasn't present in the original host
349 if (!testflag(addrlist, af_local_host_removed))
351 for (; addrlist != NULL; addrlist = addrlist->next)
352 if (addrlist->fallback_hosts == NULL)
353 addrlist->fallback_hosts = ob->fallback_hostlist;
361 /*************************************************
362 * Initialization entry point *
363 *************************************************/
365 /* Called for each instance, after its options have been read, to
366 enable consistency checks to be done, or anything else that needs
369 Argument: pointer to the transport instance block
374 smtp_transport_init(transport_instance *tblock)
376 smtp_transport_options_block *ob =
377 (smtp_transport_options_block *)(tblock->options_block);
379 /* Retry_use_local_part defaults FALSE if unset */
381 if (tblock->retry_use_local_part == TRUE_UNSET)
382 tblock->retry_use_local_part = FALSE;
384 /* Set the default port according to the protocol */
386 if (ob->port == NULL)
387 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
388 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
390 /* Set up the setup entry point, to be called before subprocesses for this
393 tblock->setup = smtp_transport_setup;
395 /* Complain if any of the timeouts are zero. */
397 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
398 ob->final_timeout <= 0)
399 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
400 "command, data, or final timeout value is zero for %s transport",
403 /* If hosts_override is set and there are local hosts, set the global
404 flag that stops verify from showing router hosts. */
406 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
408 /* If there are any fallback hosts listed, build a chain of host items
409 for them, but do not do any lookups at this time. */
411 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
414 if ( ob->gnutls_require_kx
415 || ob->gnutls_require_mac
416 || ob->gnutls_require_proto)
417 log_write(0, LOG_MAIN, "WARNING: smtp transport options"
418 " gnutls_require_kx, gnutls_require_mac and gnutls_require_protocols"
427 /*************************************************
428 * Set delivery info into all active addresses *
429 *************************************************/
431 /* Only addresses whose status is >= PENDING are relevant. A lesser
432 status means that an address is not currently being processed.
435 addrlist points to a chain of addresses
436 errno_value to put in each address's errno field
437 msg to put in each address's message field
438 rc to put in each address's transport_return field
439 pass_message if TRUE, set the "pass message" flag in the address
440 host if set, mark addrs as having used this host
442 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
443 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
444 this particular type of timeout.
450 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
451 BOOL pass_message, host_item * host)
455 if (errno_value == ERRNO_CONNECTTIMEOUT)
457 errno_value = ETIMEDOUT;
458 orvalue = RTEF_CTOUT;
460 for (addr = addrlist; addr != NULL; addr = addr->next)
462 if (addr->transport_return < PENDING) continue;
463 addr->basic_errno = errno_value;
464 addr->more_errno |= orvalue;
468 if (pass_message) setflag(addr, af_pass_message);
470 addr->transport_return = rc;
472 addr->host_used = host;
478 /*************************************************
479 * Check an SMTP response *
480 *************************************************/
482 /* This function is given an errno code and the SMTP response buffer
483 to analyse, together with the host identification for generating messages. It
484 sets an appropriate message and puts the first digit of the response code into
485 the yield variable. If no response was actually read, a suitable digit is
489 host the current host, to get its name for messages
490 errno_value pointer to the errno value
491 more_errno from the top address for use with ERRNO_FILTER_FAIL
492 buffer the SMTP response buffer
493 yield where to put a one-digit SMTP response code
494 message where to put an errror message
495 pass_message set TRUE if message is an SMTP response
497 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
501 check_response(host_item *host, int *errno_value, int more_errno,
502 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
506 if (smtp_use_pipelining &&
507 (Ustrcmp(smtp_command, "MAIL") == 0 ||
508 Ustrcmp(smtp_command, "RCPT") == 0 ||
509 Ustrcmp(smtp_command, "DATA") == 0))
512 *yield = '4'; /* Default setting is to give a temporary error */
514 /* Handle response timeout */
516 if (*errno_value == ETIMEDOUT)
518 *message = US string_sprintf("SMTP timeout after %s%s",
520 if (transport_count > 0)
521 *message = US string_sprintf("%s (%d bytes written)", *message,
526 /* Handle malformed SMTP response */
528 if (*errno_value == ERRNO_SMTPFORMAT)
530 uschar *malfresp = string_printing(buffer);
531 while (isspace(*malfresp)) malfresp++;
532 *message = *malfresp == 0
533 ? string_sprintf("Malformed SMTP reply (an empty line) "
534 "in response to %s%s", pl, smtp_command)
535 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
536 pl, smtp_command, malfresp);
540 /* Handle a failed filter process error; can't send QUIT as we mustn't
543 if (*errno_value == ERRNO_FILTER_FAIL)
545 *message = US string_sprintf("transport filter process failed (%d)%s",
547 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
551 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
554 if (*errno_value == ERRNO_CHHEADER_FAIL)
557 US string_sprintf("failed to expand headers_add or headers_remove: %s",
558 expand_string_message);
562 /* Handle failure to write a complete data block */
564 if (*errno_value == ERRNO_WRITEINCOMPLETE)
566 *message = US string_sprintf("failed to write a data block");
570 /* Handle error responses from the remote mailer. */
574 uschar *s = string_printing(buffer);
575 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
576 "%s", pl, smtp_command, s);
577 *pass_message = TRUE;
582 /* No data was read. If there is no errno, this must be the EOF (i.e.
583 connection closed) case, which causes deferral. An explicit connection reset
584 error has the same effect. Otherwise, put the host's identity in the message,
585 leaving the errno value to be interpreted as well. In all cases, we have to
586 assume the connection is now dead. */
588 if (*errno_value == 0 || *errno_value == ECONNRESET)
590 *errno_value = ERRNO_SMTPCLOSED;
591 *message = US string_sprintf("Remote host closed connection "
592 "in response to %s%s", pl, smtp_command);
594 else *message = US string_sprintf("%s [%s]", host->name, host->address);
601 /*************************************************
602 * Write error message to logs *
603 *************************************************/
605 /* This writes to the main log and to the message log.
608 addr the address item containing error information
609 host the current host
615 write_logs(address_item *addr, host_item *host)
617 uschar * message = string_sprintf("H=%s [%s]", host->name, host->address);
621 message = string_sprintf("%s: %s", message, addr->message);
622 if (addr->basic_errno > 0)
623 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
624 log_write(0, LOG_MAIN, "%s", message);
625 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
629 if (log_extra_selector & LX_outgoing_port)
630 message = string_sprintf("%s:%d", message,
631 host->port == PORT_NONE ? 25 : host->port);
632 log_write(0, LOG_MAIN, "%s %s", message, strerror(addr->basic_errno));
633 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), message,
634 strerror(addr->basic_errno));
639 msglog_line(host_item * host, uschar * message)
641 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
642 host->name, host->address, message);
647 #ifdef EXPERIMENTAL_EVENT
648 /*************************************************
649 * Post-defer action *
650 *************************************************/
652 /* This expands an arbitrary per-transport string.
653 It might, for example, be used to write to the database log.
656 addr the address item containing error information
657 host the current host
663 deferred_event_raise(address_item *addr, host_item *host)
665 uschar * action = addr->transport->event_action;
666 uschar * save_domain;
672 save_domain = deliver_domain;
673 save_local = deliver_localpart;
675 /*XXX would ip & port already be set up? */
676 deliver_host_address = string_copy(host->address);
677 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
678 event_defer_errno = addr->basic_errno;
680 router_name = addr->router->name;
681 transport_name = addr->transport->name;
682 deliver_domain = addr->domain;
683 deliver_localpart = addr->local_part;
685 (void) event_raise(action, US"msg:host:defer",
687 ? addr->basic_errno > 0
688 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
689 : string_copy(addr->message)
690 : addr->basic_errno > 0
691 ? string_copy(US strerror(addr->basic_errno))
694 deliver_localpart = save_local;
695 deliver_domain = save_domain;
696 router_name = transport_name = NULL;
702 /*************************************************
703 * Synchronize SMTP responses *
704 *************************************************/
706 /* This function is called from smtp_deliver() to receive SMTP responses from
707 the server, and match them up with the commands to which they relate. When
708 PIPELINING is not in use, this function is called after every command, and is
709 therefore somewhat over-engineered, but it is simpler to use a single scheme
710 that works both with and without PIPELINING instead of having two separate sets
713 The set of commands that are buffered up with pipelining may start with MAIL
714 and may end with DATA; in between are RCPT commands that correspond to the
715 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
716 etc.) are never buffered.
718 Errors after MAIL or DATA abort the whole process leaving the response in the
719 buffer. After MAIL, pending responses are flushed, and the original command is
720 re-instated in big_buffer for error messages. For RCPT commands, the remote is
721 permitted to reject some recipient addresses while accepting others. However
722 certain errors clearly abort the whole process. Set the value in
723 transport_return to PENDING_OK if the address is accepted. If there is a
724 subsequent general error, it will get reset accordingly. If not, it will get
725 converted to OK at the end.
728 addrlist the complete address list
729 include_affixes TRUE if affixes include in RCPT
730 sync_addr ptr to the ptr of the one to start scanning at (updated)
731 host the host we are connected to
732 count the number of responses to read
734 include_sender true if 4xx retry is to include the sender it its key
735 pending_MAIL true if the first response is for MAIL
736 pending_DATA 0 if last command sent was not DATA
737 +1 if previously had a good recipient
738 -1 if not previously had a good recipient
739 inblock incoming SMTP block
740 timeout timeout value
741 buffer buffer for reading response
742 buffsize size of buffer
744 Returns: 3 if at least one address had 2xx and one had 5xx
745 2 if at least one address had 5xx but none had 2xx
746 1 if at least one host had a 2xx response, but none had 5xx
747 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
748 -1 timeout while reading RCPT response
749 -2 I/O or other non-response error for RCPT
750 -3 DATA or MAIL failed - errno and buffer set
754 sync_responses(address_item *addrlist, BOOL include_affixes,
755 address_item **sync_addr, host_item *host, int count,
756 BOOL address_retry_include_sender, BOOL pending_MAIL,
757 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
760 address_item *addr = *sync_addr;
763 /* Handle the response for a MAIL command. On error, reinstate the original
764 command in big_buffer for error message use, and flush any further pending
765 responses before returning, except after I/O errors and timeouts. */
770 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
772 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
773 if (errno == 0 && buffer[0] != 0)
775 uschar flushbuffer[4096];
777 if (buffer[0] == '4')
779 save_errno = ERRNO_MAIL4XX;
780 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
784 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
786 && (errno != 0 || flushbuffer[0] == 0))
792 if (pending_DATA) count--; /* Number of RCPT responses to come */
793 while (count-- > 0) /* Mark any pending addrs with the host used */
795 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
796 addr->host_used = host;
803 if (pending_DATA) count--; /* Number of RCPT responses to come */
805 /* Read and handle the required number of RCPT responses, matching each one up
806 with an address by scanning for the next address whose status is PENDING_DEFER.
811 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
813 /* The address was accepted */
814 addr->host_used = host;
816 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
819 addr->transport_return = PENDING_OK;
821 /* If af_dr_retry_exists is set, there was a routing delay on this address;
822 ensure that any address-specific retry record is expunged. We do this both
823 for the basic key and for the version that also includes the sender. */
825 if (testflag(addr, af_dr_retry_exists))
827 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
829 retry_add_item(addr, altkey, rf_delete);
830 retry_add_item(addr, addr->address_retry_key, rf_delete);
834 /* Timeout while reading the response */
836 else if (errno == ETIMEDOUT)
838 int save_errno = errno;
839 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
840 transport_rcpt_address(addr, include_affixes));
841 set_errno(addrlist, save_errno, message, DEFER, FALSE, NULL);
842 retry_add_item(addr, addr->address_retry_key, 0);
843 update_waiting = FALSE;
847 /* Handle other errors in obtaining an SMTP response by returning -1. This
848 will cause all the addresses to be deferred. Restore the SMTP command in
849 big_buffer for which we are checking the response, so the error message
852 else if (errno != 0 || buffer[0] == 0)
854 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
855 transport_rcpt_address(addr, include_affixes));
859 /* Handle SMTP permanent and temporary response codes. */
864 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
865 "%s", transport_rcpt_address(addr, include_affixes),
866 string_printing(buffer));
867 setflag(addr, af_pass_message);
868 msglog_line(host, addr->message);
870 /* The response was 5xx */
872 if (buffer[0] == '5')
874 addr->transport_return = FAIL;
878 /* The response was 4xx */
882 addr->transport_return = DEFER;
883 addr->basic_errno = ERRNO_RCPT4XX;
884 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
886 /* Log temporary errors if there are more hosts to be tried.
887 If not, log this last one in the == line. */
890 log_write(0, LOG_MAIN, "H=%s [%s]: %s", host->name, host->address, addr->message);
892 /* Do not put this message on the list of those waiting for specific
893 hosts, as otherwise it is likely to be tried too often. */
895 update_waiting = FALSE;
897 /* Add a retry item for the address so that it doesn't get tried again
898 too soon. If address_retry_include_sender is true, add the sender address
901 if (address_retry_include_sender)
903 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
905 retry_add_item(addr, altkey, 0);
907 else retry_add_item(addr, addr->address_retry_key, 0);
910 } /* Loop for next RCPT response */
912 /* Update where to start at for the next block of responses, unless we
913 have already handled all the addresses. */
915 if (addr != NULL) *sync_addr = addr->next;
917 /* Handle a response to DATA. If we have not had any good recipients, either
918 previously or in this block, the response is ignored. */
920 if (pending_DATA != 0 &&
921 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
926 if (pending_DATA > 0 || (yield & 1) != 0)
928 if (errno == 0 && buffer[0] == '4')
930 errno = ERRNO_DATA4XX;
931 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
935 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
936 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
937 "is in use and there were no good recipients\n", msg);
940 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
941 present) received 3xx. If any RCPTs were handled and yielded anything other
942 than 4xx, yield will be set non-zero. */
949 /* Do the client side of smtp-level authentication */
952 buffer EHLO response from server (gets overwritten)
953 addrlist chain of potential addresses to deliver
954 host host to deliver to
956 ibp, obp comms channel control blocks
959 OK Success, or failed (but not required): global "smtp_authenticated" set
960 DEFER Failed authentication (and was required)
961 ERROR Internal problem
963 FAIL_SEND Failed communications - transmit
968 smtp_auth(uschar *buffer, unsigned bufsize, address_item *addrlist, host_item *host,
969 smtp_transport_options_block *ob, BOOL is_esmtp,
970 smtp_inblock *ibp, smtp_outblock *obp)
973 uschar *fail_reason = US"server did not advertise AUTH support";
975 smtp_authenticated = FALSE;
976 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
977 require_auth = verify_check_this_host(&(ob->hosts_require_auth), NULL,
978 host->name, host->address, NULL);
980 if (is_esmtp && !regex_AUTH) regex_AUTH =
981 regex_must_compile(US"\\n250[\\s\\-]AUTH\\s+([\\-\\w\\s]+)(?:\\n|$)",
984 if (is_esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
986 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
987 expand_nmax = -1; /* reset */
989 /* Must not do this check until after we have saved the result of the
990 regex match above. */
992 if (require_auth == OK ||
993 verify_check_this_host(&(ob->hosts_try_auth), NULL, host->name,
994 host->address, NULL) == OK)
997 fail_reason = US"no common mechanisms were found";
999 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1001 /* Scan the configured authenticators looking for one which is configured
1002 for use as a client, which is not suppressed by client_condition, and
1003 whose name matches an authentication mechanism supported by the server.
1004 If one is found, attempt to authenticate by calling its client function.
1007 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1011 (au->client_condition != NULL &&
1012 !expand_check_condition(au->client_condition, au->name,
1013 US"client authenticator")))
1015 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1017 (au->client)? "client_condition is false" :
1018 "not configured as a client");
1022 /* Loop to scan supported server mechanisms */
1027 int len = Ustrlen(au->public_name);
1028 while (isspace(*p)) p++;
1030 if (strncmpic(au->public_name, p, len) != 0 ||
1031 (p[len] != 0 && !isspace(p[len])))
1033 while (*p != 0 && !isspace(*p)) p++;
1037 /* Found data for a listed mechanism. Call its client entry. Set
1038 a flag in the outblock so that data is overwritten after sending so
1039 that reflections don't show it. */
1041 fail_reason = US"authentication attempt(s) failed";
1042 obp->authenticating = TRUE;
1043 rc = (au->info->clientcode)(au, ibp, obp,
1044 ob->command_timeout, buffer, bufsize);
1045 obp->authenticating = FALSE;
1046 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1049 /* A temporary authentication failure must hold up delivery to
1050 this host. After a permanent authentication failure, we carry on
1051 to try other authentication methods. If all fail hard, try to
1052 deliver the message unauthenticated unless require_auth was set. */
1057 smtp_authenticated = TRUE; /* stops the outer loop */
1058 client_authenticator = au->name;
1059 if (au->set_client_id != NULL)
1060 client_authenticated_id = expand_string(au->set_client_id);
1063 /* Failure after writing a command */
1068 /* Failure after reading a response */
1071 if (errno != 0 || buffer[0] != '5') return FAIL;
1072 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1073 au->name, host->name, host->address, buffer);
1076 /* Failure by some other means. In effect, the authenticator
1077 decided it wasn't prepared to handle this case. Typically this
1078 is the result of "fail" in an expansion string. Do we need to
1079 log anything here? Feb 2006: a message is now put in the buffer
1080 if logging is required. */
1084 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1085 "authentication H=%s [%s] %s", au->name, host->name,
1086 host->address, buffer);
1089 /* Internal problem, message in buffer. */
1092 set_errno(addrlist, 0, string_copy(buffer), DEFER, FALSE, NULL);
1096 break; /* If not authenticated, try next authenticator */
1097 } /* Loop for scanning supported server mechanisms */
1098 } /* Loop for further authenticators */
1102 /* If we haven't authenticated, but are required to, give up. */
1104 if (require_auth == OK && !smtp_authenticated)
1106 set_errno(addrlist, ERRNO_AUTHFAIL,
1107 string_sprintf("authentication required but %s", fail_reason), DEFER,
1116 /* Construct AUTH appendix string for MAIL TO */
1119 buffer to build string
1120 addrlist chain of potential addresses to deliver
1121 ob transport options
1123 Globals smtp_authenticated
1124 client_authenticated_sender
1125 Return True on error, otherwise buffer has (possibly empty) terminated string
1129 smtp_mail_auth_str(uschar *buffer, unsigned bufsize, address_item *addrlist,
1130 smtp_transport_options_block *ob)
1132 uschar *local_authenticated_sender = authenticated_sender;
1135 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n", authenticated_sender, ob->authenticated_sender, smtp_authenticated?"Y":"N");
1138 if (ob->authenticated_sender != NULL)
1140 uschar *new = expand_string(ob->authenticated_sender);
1143 if (!expand_string_forcedfail)
1145 uschar *message = string_sprintf("failed to expand "
1146 "authenticated_sender: %s", expand_string_message);
1147 set_errno(addrlist, 0, message, DEFER, FALSE, NULL);
1151 else if (new[0] != 0) local_authenticated_sender = new;
1154 /* Add the authenticated sender address if present */
1156 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1157 local_authenticated_sender != NULL)
1159 string_format(buffer, bufsize, " AUTH=%s",
1160 auth_xtextencode(local_authenticated_sender,
1161 Ustrlen(local_authenticated_sender)));
1162 client_authenticated_sender = string_copy(local_authenticated_sender);
1172 #ifdef EXPERIMENTAL_DANE
1174 tlsa_lookup(const host_item * host, dns_answer * dnsa,
1175 BOOL dane_required, BOOL * dane)
1177 /* move this out to host.c given the similarity to dns_lookup() ? */
1179 uschar * fullname = buffer;
1181 /* TLSA lookup string */
1182 (void)sprintf(CS buffer, "_%d._tcp.%.256s", host->port, host->name);
1184 switch (dns_lookup(dnsa, buffer, T_TLSA, &fullname))
1187 return DEFER; /* just defer this TLS'd conn */
1193 log_write(0, LOG_MAIN, "DANE error: TLSA lookup failed");
1199 if (!dns_is_secure(dnsa))
1201 log_write(0, LOG_MAIN, "DANE error: TLSA lookup not DNSSEC");
1212 /*************************************************
1213 * Deliver address list to given host *
1214 *************************************************/
1216 /* If continue_hostname is not null, we get here only when continuing to
1217 deliver down an existing channel. The channel was passed as the standard
1218 input. TLS is never active on a passed channel; the previous process always
1219 closes it down before passing the connection on.
1221 Otherwise, we have to make a connection to the remote host, and do the
1222 initial protocol exchange.
1224 When running as an MUA wrapper, if the sender or any recipient is rejected,
1225 temporarily or permanently, we force failure for all recipients.
1228 addrlist chain of potential addresses to deliver; only those whose
1229 transport_return field is set to PENDING_DEFER are currently
1230 being processed; others should be skipped - they have either
1231 been delivered to an earlier host or IP address, or been
1232 failed by one of them.
1233 host host to deliver to
1234 host_af AF_INET or AF_INET6
1235 port default TCP/IP port to use, in host byte order
1236 interface interface to bind to, or NULL
1237 tblock transport instance block
1238 message_defer set TRUE if yield is OK, but all addresses were deferred
1239 because of a non-recipient, non-host failure, that is, a
1240 4xx response to MAIL FROM, DATA, or ".". This is a defer
1241 that is specific to the message.
1242 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1243 a second attempt after TLS initialization fails
1245 Returns: OK - the connection was made and the delivery attempted;
1246 the result for each address is in its data block.
1247 DEFER - the connection could not be made, or something failed
1248 while setting up the SMTP session, or there was a
1249 non-message-specific error, such as a timeout.
1250 ERROR - a filter command is specified for this transport,
1251 and there was a problem setting it up; OR helo_data
1252 or add_headers or authenticated_sender is specified
1253 for this transport, and the string failed to expand
1257 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
1258 uschar *interface, transport_instance *tblock,
1259 BOOL *message_defer, BOOL suppress_tls)
1262 address_item *sync_addr;
1263 address_item *first_addr = addrlist;
1268 time_t start_delivery_time = time(NULL);
1269 smtp_transport_options_block *ob =
1270 (smtp_transport_options_block *)(tblock->options_block);
1271 BOOL lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
1272 BOOL smtps = strcmpic(ob->protocol, US"smtps") == 0;
1274 BOOL send_rset = TRUE;
1275 BOOL send_quit = TRUE;
1276 BOOL setting_up = TRUE;
1277 BOOL completed_address = FALSE;
1280 BOOL pass_message = FALSE;
1281 #ifndef DISABLE_PRDR
1282 BOOL prdr_offered = FALSE;
1285 #ifdef EXPERIMENTAL_DSN
1286 BOOL dsn_all_lasthop = TRUE;
1288 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1290 dns_answer tlsa_dnsa;
1292 smtp_inblock inblock;
1293 smtp_outblock outblock;
1294 int max_rcpt = tblock->max_addresses;
1295 uschar *igquotstr = US"";
1296 uschar *helo_data = NULL;
1297 uschar *message = NULL;
1298 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
1300 uschar buffer[4096];
1301 uschar inbuffer[4096];
1302 uschar outbuffer[4096];
1304 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
1306 *message_defer = FALSE;
1307 smtp_command = US"initial connection";
1308 if (max_rcpt == 0) max_rcpt = 999999;
1310 /* Set up the buffer for reading SMTP response packets. */
1312 inblock.buffer = inbuffer;
1313 inblock.buffersize = sizeof(inbuffer);
1314 inblock.ptr = inbuffer;
1315 inblock.ptrend = inbuffer;
1317 /* Set up the buffer for holding SMTP commands while pipelining */
1319 outblock.buffer = outbuffer;
1320 outblock.buffersize = sizeof(outbuffer);
1321 outblock.ptr = outbuffer;
1322 outblock.cmd_count = 0;
1323 outblock.authenticating = FALSE;
1325 /* Reset the parameters of a TLS session. */
1328 tls_out.cipher = NULL; /* the one we may use for this transport */
1329 tls_out.ourcert = NULL;
1330 tls_out.peercert = NULL;
1331 tls_out.peerdn = NULL;
1332 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1335 tls_out.ocsp = OCSP_NOT_REQ;
1337 /* Flip the legacy TLS-related variables over to the outbound set in case
1338 they're used in the context of the transport. Don't bother resetting
1339 afterward as we're in a subprocess. */
1341 tls_modify_variables(&tls_out);
1346 set_errno(addrlist, 0, US"TLS support not available", DEFER, FALSE, NULL);
1351 /* Make a connection to the host if this isn't a continued delivery, and handle
1352 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
1353 specially so they can be identified for retries. */
1355 if (continue_hostname == NULL)
1357 /* This puts port into host->port */
1358 inblock.sock = outblock.sock =
1359 smtp_connect(host, host_af, port, interface, ob->connect_timeout,
1360 ob->keepalive, ob->dscp
1361 #ifdef EXPERIMENTAL_EVENT
1362 , tblock->event_action
1366 if (inblock.sock < 0)
1368 set_errno(addrlist, (errno == ETIMEDOUT)? ERRNO_CONNECTTIMEOUT : errno,
1369 NULL, DEFER, FALSE, NULL);
1373 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1377 tls_out.dane_verified = FALSE;
1378 tls_out.tlsa_usage = 0;
1380 dane_required = verify_check_this_host(&ob->hosts_require_dane, NULL,
1381 host->name, host->address, NULL) == OK;
1383 if (host->dnssec == DS_YES)
1386 || verify_check_this_host(&ob->hosts_try_dane, NULL,
1387 host->name, host->address, NULL) == OK
1389 if ((rc = tlsa_lookup(host, &tlsa_dnsa, dane_required, &dane)) != OK)
1392 else if (dane_required)
1394 log_write(0, LOG_MAIN, "DANE error: %s lookup not DNSSEC", host->name);
1399 ob->tls_tempfail_tryclear = FALSE;
1403 /* Expand the greeting message while waiting for the initial response. (Makes
1404 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1405 delayed till here so that $sending_interface and $sending_port are set. */
1407 helo_data = expand_string(ob->helo_data);
1409 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1410 is nevertheless a reasonably clean way of programming this kind of logic,
1411 where you want to escape on any error. */
1415 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1416 ob->command_timeout)) goto RESPONSE_FAILED;
1418 #ifdef EXPERIMENTAL_EVENT
1421 lookup_dnssec_authenticated = host->dnssec==DS_YES ? US"yes"
1422 : host->dnssec==DS_NO ? US"no" : NULL;
1423 s = event_raise(tblock->event_action, US"smtp:connect", buffer);
1426 set_errno(addrlist, 0,
1427 string_sprintf("deferred by smtp:connect event expansion: %s", s),
1428 DEFER, FALSE, NULL);
1435 /* Now check if the helo_data expansion went well, and sign off cleanly if
1438 if (helo_data == NULL)
1440 uschar *message = string_sprintf("failed to expand helo_data: %s",
1441 expand_string_message);
1442 set_errno(addrlist, 0, message, DEFER, FALSE, NULL);
1448 /** Debugging without sending a message
1449 addrlist->transport_return = DEFER;
1453 /* Errors that occur after this point follow an SMTP command, which is
1454 left in big_buffer by smtp_write_command() for use in error messages. */
1456 smtp_command = big_buffer;
1458 /* Tell the remote who we are...
1460 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1461 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1462 greeting is of this form. The assumption was that the far end supports it
1463 properly... but experience shows that there are some that give 5xx responses,
1464 even though the banner includes "ESMTP" (there's a bloody-minded one that
1465 says "ESMTP not spoken here"). Cope with that case.
1467 September 2000: Time has passed, and it seems reasonable now to always send
1468 EHLO at the start. It is also convenient to make the change while installing
1471 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1472 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1473 would be no way to send out the mails, so there is now a host list
1474 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1475 PIPELINING problem as well. Maybe it can also be useful to cure other
1476 problems with broken servers.
1478 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1479 Then somebody tried it with a Microsoft mailer... It seems that all other
1480 mailers use upper case for some reason (the RFC is quite clear about case
1481 independence) so, for peace of mind, I gave in. */
1483 esmtp = verify_check_this_host(&(ob->hosts_avoid_esmtp), NULL,
1484 host->name, host->address, NULL) != OK;
1486 /* Alas; be careful, since this goto is not an error-out, so conceivably
1487 we might set data between here and the target which we assume to exist
1488 and be usable. I can see this coming back to bite us. */
1493 suppress_tls = FALSE;
1494 ob->tls_tempfail_tryclear = FALSE;
1495 smtp_command = US"SSL-on-connect";
1502 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1503 lmtp? "LHLO" : "EHLO", helo_data) < 0)
1505 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1506 ob->command_timeout))
1508 if (errno != 0 || buffer[0] == 0 || lmtp) goto RESPONSE_FAILED;
1515 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1520 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1522 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1523 ob->command_timeout)) goto RESPONSE_FAILED;
1526 /* Set IGNOREQUOTA if the response to LHLO specifies support and the
1527 lmtp_ignore_quota option was set. */
1529 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1530 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1531 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1533 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1536 tls_offered = esmtp &&
1537 pcre_exec(regex_STARTTLS, NULL, CS buffer, Ustrlen(buffer), 0,
1538 PCRE_EOPT, NULL, 0) >= 0;
1541 #ifndef DISABLE_PRDR
1542 prdr_offered = esmtp &&
1543 (pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(buffer), 0,
1544 PCRE_EOPT, NULL, 0) >= 0) &&
1545 (verify_check_this_host(&(ob->hosts_try_prdr), NULL, host->name,
1546 host->address, NULL) == OK);
1549 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1553 /* For continuing deliveries down the same channel, the socket is the standard
1554 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1555 below). Set up the pointer to where subsequent commands will be left, for
1556 error messages. Note that smtp_use_size and smtp_use_pipelining will have been
1557 set from the command line if they were set in the process that passed the
1562 inblock.sock = outblock.sock = fileno(stdin);
1563 smtp_command = big_buffer;
1564 host->port = port; /* Record the port that was used */
1567 /* If TLS is available on this connection, whether continued or not, attempt to
1568 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1569 send another EHLO - the server may give a different answer in secure mode. We
1570 use a separate buffer for reading the response to STARTTLS so that if it is
1571 negative, the original EHLO data is available for subsequent analysis, should
1572 the client not be required to use TLS. If the response is bad, copy the buffer
1573 for error analysis. */
1576 if (tls_offered && !suppress_tls &&
1577 verify_check_this_host(&(ob->hosts_avoid_tls), NULL, host->name,
1578 host->address, NULL) != OK)
1580 uschar buffer2[4096];
1581 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1584 /* If there is an I/O error, transmission of this message is deferred. If
1585 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1586 false, we also defer. However, if there is a temporary rejection of STARTTLS
1587 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1588 STARTTLS, we carry on. This means we will try to send the message in clear,
1589 unless the host is in hosts_require_tls (tested below). */
1591 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1592 ob->command_timeout))
1594 if (errno != 0 || buffer2[0] == 0 ||
1595 (buffer2[0] == '4' && !ob->tls_tempfail_tryclear))
1597 Ustrncpy(buffer, buffer2, sizeof(buffer));
1598 goto RESPONSE_FAILED;
1602 /* STARTTLS accepted: try to negotiate a TLS session. */
1607 int rc = tls_client_start(inblock.sock, host, addrlist, tblock
1608 # ifdef EXPERIMENTAL_DANE
1609 , dane ? &tlsa_dnsa : NULL
1613 /* TLS negotiation failed; give an error. From outside, this function may
1614 be called again to try in clear on a new connection, if the options permit
1615 it for this host. */
1619 save_errno = ERRNO_TLSFAILURE;
1620 message = US"failure while setting up TLS session";
1625 /* TLS session is set up */
1627 for (addr = addrlist; addr != NULL; addr = addr->next)
1628 if (addr->transport_return == PENDING_DEFER)
1630 addr->cipher = tls_out.cipher;
1631 addr->ourcert = tls_out.ourcert;
1632 addr->peercert = tls_out.peercert;
1633 addr->peerdn = tls_out.peerdn;
1634 addr->ocsp = tls_out.ocsp;
1639 /* if smtps, we'll have smtp_command set to something else; always safe to
1641 smtp_command = big_buffer;
1643 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1644 helo_data is null, we are dealing with a connection that was passed from
1645 another process, and so we won't have expanded helo_data above. We have to
1646 expand it here. $sending_ip_address and $sending_port are set up right at the
1647 start of the Exim process (in exim.c). */
1649 if (tls_out.active >= 0)
1652 if (helo_data == NULL)
1654 helo_data = expand_string(ob->helo_data);
1655 if (helo_data == NULL)
1657 uschar *message = string_sprintf("failed to expand helo_data: %s",
1658 expand_string_message);
1659 set_errno(addrlist, 0, message, DEFER, FALSE, NULL);
1665 /* For SMTPS we need to wait for the initial OK response. */
1668 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1669 ob->command_timeout)) goto RESPONSE_FAILED;
1673 greeting_cmd = "EHLO";
1676 greeting_cmd = "HELO";
1678 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1681 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1682 lmtp? "LHLO" : greeting_cmd, helo_data) < 0)
1684 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1685 ob->command_timeout))
1686 goto RESPONSE_FAILED;
1689 /* If the host is required to use a secure channel, ensure that we
1693 # ifdef EXPERIMENTAL_DANE
1696 verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
1697 host->address, NULL) == OK
1700 save_errno = ERRNO_TLSREQUIRED;
1701 message = string_sprintf("a TLS session is required, but %s",
1702 tls_offered? "an attempt to start TLS failed" :
1703 "the server did not offer TLS support");
1706 #endif /*SUPPORT_TLS*/
1708 /* If TLS is active, we have just started it up and re-done the EHLO command,
1709 so its response needs to be analyzed. If TLS is not active and this is a
1710 continued session down a previously-used socket, we haven't just done EHLO, so
1713 if (continue_hostname == NULL
1715 || tls_out.active >= 0
1719 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
1720 lmtp_ignore_quota option was set. */
1722 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1723 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1724 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1726 /* If the response to EHLO specified support for the SIZE parameter, note
1727 this, provided size_addition is non-negative. */
1729 smtp_use_size = esmtp && ob->size_addition >= 0 &&
1730 pcre_exec(regex_SIZE, NULL, CS buffer, Ustrlen(CS buffer), 0,
1731 PCRE_EOPT, NULL, 0) >= 0;
1733 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
1734 the current host, esmtp will be false, so PIPELINING can never be used. If
1735 the current host matches hosts_avoid_pipelining, don't do it. */
1737 smtp_use_pipelining = esmtp &&
1738 verify_check_this_host(&(ob->hosts_avoid_pipelining), NULL, host->name,
1739 host->address, NULL) != OK &&
1740 pcre_exec(regex_PIPELINING, NULL, CS buffer, Ustrlen(CS buffer), 0,
1741 PCRE_EOPT, NULL, 0) >= 0;
1743 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
1744 smtp_use_pipelining? "" : "not ");
1746 #ifndef DISABLE_PRDR
1747 prdr_offered = esmtp &&
1748 pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(CS buffer), 0,
1749 PCRE_EOPT, NULL, 0) >= 0 &&
1750 verify_check_this_host(&(ob->hosts_try_prdr), NULL, host->name,
1751 host->address, NULL) == OK;
1754 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1757 #ifdef EXPERIMENTAL_DSN
1758 /* Note if the server supports DSN */
1759 smtp_use_dsn = esmtp && pcre_exec(regex_DSN, NULL, CS buffer, (int)Ustrlen(CS buffer), 0,
1760 PCRE_EOPT, NULL, 0) >= 0;
1761 DEBUG(D_transport) debug_printf("use_dsn=%d\n", smtp_use_dsn);
1764 /* Note if the response to EHLO specifies support for the AUTH extension.
1765 If it has, check that this host is one we want to authenticate to, and do
1766 the business. The host name and address must be available when the
1767 authenticator's client driver is running. */
1769 switch (yield = smtp_auth(buffer, sizeof(buffer), addrlist, host,
1770 ob, esmtp, &inblock, &outblock))
1772 default: goto SEND_QUIT;
1774 case FAIL_SEND: goto SEND_FAILED;
1775 case FAIL: goto RESPONSE_FAILED;
1779 /* The setting up of the SMTP call is now complete. Any subsequent errors are
1780 message-specific. */
1784 /* If there is a filter command specified for this transport, we can now
1785 set it up. This cannot be done until the identify of the host is known. */
1787 if (tblock->filter_command != NULL)
1791 sprintf(CS buffer, "%.50s transport", tblock->name);
1792 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
1793 TRUE, DEFER, addrlist, buffer, NULL);
1794 transport_filter_timeout = tblock->filter_timeout;
1796 /* On failure, copy the error to all addresses, abandon the SMTP call, and
1801 set_errno(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
1809 /* For messages that have more than the maximum number of envelope recipients,
1810 we want to send several transactions down the same SMTP connection. (See
1811 comments in deliver.c as to how this reconciles, heuristically, with
1812 remote_max_parallel.) This optimization was added to Exim after the following
1813 code was already working. The simplest way to put it in without disturbing the
1814 code was to use a goto to jump back to this point when there is another
1815 transaction to handle. */
1818 sync_addr = first_addr;
1822 completed_address = FALSE;
1825 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
1826 qualification, send it, adding something to the message size to allow for
1827 imprecision and things that get added en route. Exim keeps the number of lines
1828 in a message, so we can give an accurate value for the original message, but we
1829 need some additional to handle added headers. (Double "." characters don't get
1830 included in the count.) */
1837 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
1841 #ifndef DISABLE_PRDR
1842 prdr_active = FALSE;
1845 for (addr = first_addr; addr; addr = addr->next)
1846 if (addr->transport_return == PENDING_DEFER)
1848 for (addr = addr->next; addr; addr = addr->next)
1849 if (addr->transport_return == PENDING_DEFER)
1850 { /* at least two recipients to send */
1852 sprintf(CS p, " PRDR"); p += 5;
1860 #ifdef EXPERIMENTAL_DSN
1861 /* check if all addresses have lasthop flag */
1862 /* do not send RET and ENVID if true */
1863 dsn_all_lasthop = TRUE;
1864 for (addr = first_addr;
1865 address_count < max_rcpt && addr != NULL;
1867 if ((addr->dsn_flags & rf_dsnlasthop) != 1)
1868 dsn_all_lasthop = FALSE;
1870 /* Add any DSN flags to the mail command */
1872 if ((smtp_use_dsn) && (dsn_all_lasthop == FALSE))
1874 if (dsn_ret == dsn_ret_hdrs)
1876 Ustrcpy(p, " RET=HDRS");
1879 else if (dsn_ret == dsn_ret_full)
1881 Ustrcpy(p, " RET=FULL");
1884 if (dsn_envid != NULL)
1886 string_format(p, sizeof(buffer) - (p-buffer), " ENVID=%s", dsn_envid);
1892 /* If an authenticated_sender override has been specified for this transport
1893 instance, expand it. If the expansion is forced to fail, and there was already
1894 an authenticated_sender for this message, the original value will be used.
1895 Other expansion failures are serious. An empty result is ignored, but there is
1896 otherwise no check - this feature is expected to be used with LMTP and other
1897 cases where non-standard addresses (e.g. without domains) might be required. */
1899 if (smtp_mail_auth_str(p, sizeof(buffer) - (p-buffer), addrlist, ob))
1905 /* From here until we send the DATA command, we can make use of PIPELINING
1906 if the server host supports it. The code has to be able to check the responses
1907 at any point, for when the buffer fills up, so we write it totally generally.
1908 When PIPELINING is off, each command written reports that it has flushed the
1911 pending_MAIL = TRUE; /* The block starts with MAIL */
1913 rc = smtp_write_command(&outblock, smtp_use_pipelining,
1914 "MAIL FROM:<%s>%s\r\n", return_path, buffer);
1915 mail_command = string_copy(big_buffer); /* Save for later error message */
1919 case -1: /* Transmission error */
1922 case +1: /* Block was sent */
1923 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1924 ob->command_timeout))
1926 if (errno == 0 && buffer[0] == '4')
1928 errno = ERRNO_MAIL4XX;
1929 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1931 goto RESPONSE_FAILED;
1933 pending_MAIL = FALSE;
1937 /* Pass over all the relevant recipient addresses for this host, which are the
1938 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
1939 several before we have to read the responses for those seen so far. This
1940 checking is done by a subroutine because it also needs to be done at the end.
1941 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
1942 the next one if not all are sent.
1944 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
1945 last address because we want to abort if any recipients have any kind of
1946 problem, temporary or permanent. We know that all recipient addresses will have
1947 the PENDING_DEFER status, because only one attempt is ever made, and we know
1948 that max_rcpt will be large, so all addresses will be done at once. */
1950 for (addr = first_addr;
1951 address_count < max_rcpt && addr != NULL;
1957 #ifdef EXPERIMENTAL_DSN
1958 addr->dsn_aware = smtp_use_dsn ? dsn_support_yes : dsn_support_no;
1961 if (addr->transport_return != PENDING_DEFER) continue;
1964 no_flush = smtp_use_pipelining && (!mua_wrapper || addr->next != NULL);
1966 #ifdef EXPERIMENTAL_DSN
1967 /* Add any DSN flags to the rcpt command and add to the sent string */
1972 if (smtp_use_dsn && (addr->dsn_flags & rf_dsnlasthop) != 1)
1974 if ((addr->dsn_flags & rf_dsnflags) != 0)
1978 Ustrcpy(p, " NOTIFY=");
1980 for (i = 0; i < 4; i++)
1981 if ((addr->dsn_flags & rf_list[i]) != 0)
1983 if (!first) *p++ = ',';
1985 Ustrcpy(p, rf_names[i]);
1990 if (addr->dsn_orcpt != NULL)
1992 string_format(p, sizeof(buffer) - (p-buffer), " ORCPT=%s",
2000 /* Now send the RCPT command, and process outstanding responses when
2001 necessary. After a timeout on RCPT, we just end the function, leaving the
2002 yield as OK, because this error can often mean that there is a problem with
2003 just one address, so we don't want to delay the host. */
2005 #ifdef EXPERIMENTAL_DSN
2006 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s%s\r\n",
2007 transport_rcpt_address(addr, tblock->rcpt_include_affixes), igquotstr, buffer);
2009 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s\r\n",
2010 transport_rcpt_address(addr, tblock->rcpt_include_affixes), igquotstr);
2013 if (count < 0) goto SEND_FAILED;
2016 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
2017 &sync_addr, host, count, ob->address_retry_include_sender,
2018 pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
2021 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2022 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2025 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2026 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2027 case 0: /* No 2xx or 5xx, but no probs */
2030 case -1: goto END_OFF; /* Timeout on RCPT */
2031 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
2033 pending_MAIL = FALSE; /* Dealt with MAIL */
2035 } /* Loop for next address */
2037 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
2038 permanently or temporarily. We should have flushed and synced after the last
2043 address_item *badaddr;
2044 for (badaddr = first_addr; badaddr != NULL; badaddr = badaddr->next)
2046 if (badaddr->transport_return != PENDING_OK) break;
2048 if (badaddr != NULL)
2050 set_errno(addrlist, 0, badaddr->message, FAIL,
2051 testflag(badaddr, af_pass_message), NULL);
2056 /* If ok is TRUE, we know we have got at least one good recipient, and must now
2057 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
2058 have a good recipient buffered up if we are pipelining. We don't want to waste
2059 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
2060 are pipelining. The responses are all handled by sync_responses(). */
2062 if (ok || (smtp_use_pipelining && !mua_wrapper))
2064 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
2065 if (count < 0) goto SEND_FAILED;
2066 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
2067 host, count, ob->address_retry_include_sender, pending_MAIL,
2068 ok? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
2070 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2071 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2074 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2075 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2076 case 0: break; /* No 2xx or 5xx, but no probs */
2078 case -1: goto END_OFF; /* Timeout on RCPT */
2079 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2083 /* Save the first address of the next batch. */
2087 /* If there were no good recipients (but otherwise there have been no
2088 problems), just set ok TRUE, since we have handled address-specific errors
2089 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
2090 for handling the SMTP dot-handling protocol, flagging to apply to headers as
2091 well as body. Set the appropriate timeout value to be used for each chunk.
2092 (Haven't been able to make it work using select() for writing yet.) */
2094 if (!ok) ok = TRUE; else
2096 sigalrm_seen = FALSE;
2097 transport_write_timeout = ob->data_timeout;
2098 smtp_command = US"sending data block"; /* For error messages */
2099 DEBUG(D_transport|D_v)
2100 debug_printf(" SMTP>> writing message and terminating \".\"\n");
2101 transport_count = 0;
2103 #ifndef DISABLE_DKIM
2104 ok = dkim_transport_write_message(addrlist, inblock.sock,
2105 topt_use_crlf | topt_end_dot | topt_escape_headers |
2106 (tblock->body_only? topt_no_headers : 0) |
2107 (tblock->headers_only? topt_no_body : 0) |
2108 (tblock->return_path_add? topt_add_return_path : 0) |
2109 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
2110 (tblock->envelope_to_add? topt_add_envelope_to : 0),
2111 0, /* No size limit */
2112 tblock->add_headers, tblock->remove_headers,
2113 US".", US"..", /* Escaping strings */
2114 tblock->rewrite_rules, tblock->rewrite_existflags,
2115 ob->dkim_private_key, ob->dkim_domain, ob->dkim_selector,
2116 ob->dkim_canon, ob->dkim_strict, ob->dkim_sign_headers
2119 ok = transport_write_message(addrlist, inblock.sock,
2120 topt_use_crlf | topt_end_dot | topt_escape_headers |
2121 (tblock->body_only? topt_no_headers : 0) |
2122 (tblock->headers_only? topt_no_body : 0) |
2123 (tblock->return_path_add? topt_add_return_path : 0) |
2124 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
2125 (tblock->envelope_to_add? topt_add_envelope_to : 0),
2126 0, /* No size limit */
2127 tblock->add_headers, tblock->remove_headers,
2128 US".", US"..", /* Escaping strings */
2129 tblock->rewrite_rules, tblock->rewrite_existflags);
2132 /* transport_write_message() uses write() because it is called from other
2133 places to write to non-sockets. This means that under some OS (e.g. Solaris)
2134 it can exit with "Broken pipe" as its error. This really means that the
2135 socket got closed at the far end. */
2137 transport_write_timeout = 0; /* for subsequent transports */
2139 /* Failure can either be some kind of I/O disaster (including timeout),
2140 or the failure of a transport filter or the expansion of added headers. */
2144 buffer[0] = 0; /* There hasn't been a response */
2145 goto RESPONSE_FAILED;
2148 /* We used to send the terminating "." explicitly here, but because of
2149 buffering effects at both ends of TCP/IP connections, you don't gain
2150 anything by keeping it separate, so it might as well go in the final
2151 data buffer for efficiency. This is now done by setting the topt_end_dot
2154 smtp_command = US"end of data";
2156 #ifndef DISABLE_PRDR
2157 /* For PRDR we optionally get a partial-responses warning
2158 * followed by the individual responses, before going on with
2159 * the overall response. If we don't get the warning then deal
2160 * with per non-PRDR. */
2163 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '3',
2165 if (!ok && errno == 0)
2168 case '2': prdr_active = FALSE;
2171 case '4': errno = ERRNO_DATA4XX;
2172 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2179 /* For non-PRDR SMTP, we now read a single response that applies to the
2180 whole message. If it is OK, then all the addresses have been delivered. */
2184 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2186 if (!ok && errno == 0 && buffer[0] == '4')
2188 errno = ERRNO_DATA4XX;
2189 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2193 /* For LMTP, we get back a response for every RCPT command that we sent;
2194 some may be accepted and some rejected. For those that get a response, their
2195 status is fixed; any that are accepted have been handed over, even if later
2196 responses crash - at least, that's how I read RFC 2033.
2198 If all went well, mark the recipient addresses as completed, record which
2199 host/IPaddress they were delivered to, and cut out RSET when sending another
2200 message down the same channel. Write the completed addresses to the journal
2201 now so that they are recorded in case there is a crash of hardware or
2202 software before the spool gets updated. Also record the final SMTP
2203 confirmation if needed (for SMTP only). */
2208 int delivery_time = (int)(time(NULL) - start_delivery_time);
2210 uschar *conf = NULL;
2213 /* Set up confirmation if needed - applies only to SMTP */
2216 #ifndef EXPERIMENTAL_EVENT
2217 (log_extra_selector & LX_smtp_confirmation) != 0 &&
2222 uschar *s = string_printing(buffer);
2223 conf = (s == buffer)? (uschar *)string_copy(s) : s;
2226 /* Process all transported addresses - for LMTP or PRDR, read a status for
2229 for (addr = addrlist; addr != first_addr; addr = addr->next)
2231 if (addr->transport_return != PENDING_OK) continue;
2233 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
2234 remaining addresses. Otherwise, it's a return code for just the one
2235 address. For temporary errors, add a retry item for the address so that
2236 it doesn't get tried again too soon. */
2238 #ifndef DISABLE_PRDR
2239 if (lmtp || prdr_active)
2244 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2247 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
2248 addr->message = string_sprintf(
2249 #ifndef DISABLE_PRDR
2250 "%s error after %s: %s", prdr_active ? "PRDR":"LMTP",
2252 "LMTP error after %s: %s",
2254 big_buffer, string_printing(buffer));
2255 setflag(addr, af_pass_message); /* Allow message to go to user */
2256 if (buffer[0] == '5')
2257 addr->transport_return = FAIL;
2260 errno = ERRNO_DATA4XX;
2261 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2262 addr->transport_return = DEFER;
2263 #ifndef DISABLE_PRDR
2266 retry_add_item(addr, addr->address_retry_key, 0);
2270 completed_address = TRUE; /* NOW we can set this flag */
2271 if ((log_extra_selector & LX_smtp_confirmation) != 0)
2273 uschar *s = string_printing(buffer);
2274 conf = (s == buffer)? (uschar *)string_copy(s) : s;
2278 /* SMTP, or success return from LMTP for this address. Pass back the
2279 actual host that was used. */
2281 addr->transport_return = OK;
2282 addr->more_errno = delivery_time;
2283 addr->host_used = host;
2284 addr->special_action = flag;
2285 addr->message = conf;
2286 #ifndef DISABLE_PRDR
2287 if (prdr_active) addr->flags |= af_prdr_used;
2291 #ifndef DISABLE_PRDR
2295 /* Update the journal. For homonymic addresses, use the base address plus
2296 the transport name. See lots of comments in deliver.c about the reasons
2297 for the complications when homonyms are involved. Just carry on after
2298 write error, as it may prove possible to update the spool file later. */
2300 if (testflag(addr, af_homonym))
2301 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2303 sprintf(CS buffer, "%.500s\n", addr->unique);
2305 DEBUG(D_deliver) debug_printf("journalling %s", buffer);
2306 len = Ustrlen(CS buffer);
2307 if (write(journal_fd, buffer, len) != len)
2308 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2309 "%s: %s", buffer, strerror(errno));
2313 #ifndef DISABLE_PRDR
2316 /* PRDR - get the final, overall response. For any non-success
2317 upgrade all the address statuses. */
2318 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2322 if(errno == 0 && buffer[0] == '4')
2324 errno = ERRNO_DATA4XX;
2325 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2327 for (addr = addrlist; addr != first_addr; addr = addr->next)
2328 if (buffer[0] == '5' || addr->transport_return == OK)
2329 addr->transport_return = PENDING_OK; /* allow set_errno action */
2330 goto RESPONSE_FAILED;
2333 /* Update the journal, or setup retry. */
2334 for (addr = addrlist; addr != first_addr; addr = addr->next)
2335 if (addr->transport_return == OK)
2337 if (testflag(addr, af_homonym))
2338 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2340 sprintf(CS buffer, "%.500s\n", addr->unique);
2342 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s", buffer);
2343 len = Ustrlen(CS buffer);
2344 if (write(journal_fd, buffer, len) != len)
2345 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2346 "%s: %s", buffer, strerror(errno));
2348 else if (addr->transport_return == DEFER)
2349 retry_add_item(addr, addr->address_retry_key, -2);
2353 /* Ensure the journal file is pushed out to disk. */
2355 if (EXIMfsync(journal_fd) < 0)
2356 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
2362 /* Handle general (not specific to one address) failures here. The value of ok
2363 is used to skip over this code on the falling through case. A timeout causes a
2364 deferral. Other errors may defer or fail according to the response code, and
2365 may set up a special errno value, e.g. after connection chopped, which is
2366 assumed if errno == 0 and there is no text in the buffer. If control reaches
2367 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
2368 the problem is not related to this specific message. */
2377 send_quit = check_response(host, &save_errno, addrlist->more_errno,
2378 buffer, &code, &message, &pass_message);
2384 message = US string_sprintf("send() to %s [%s] failed: %s",
2385 host->name, host->address, strerror(save_errno));
2389 /* This label is jumped to directly when a TLS negotiation has failed,
2390 or was not done for a host for which it is required. Values will be set
2391 in message and save_errno, and setting_up will always be true. Treat as
2392 a temporary error. */
2399 /* If the failure happened while setting up the call, see if the failure was
2400 a 5xx response (this will either be on connection, or following HELO - a 5xx
2401 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
2402 never going to accept them. For other errors during setting up (timeouts or
2403 whatever), defer all addresses, and yield DEFER, so that the host is not
2404 tried again for a while. */
2407 ok = FALSE; /* For when reached by GOTO */
2412 set_errno(addrlist, save_errno, message, FAIL, pass_message, host);
2415 set_errno(addrlist, save_errno, message, DEFER, pass_message, host);
2420 /* We want to handle timeouts after MAIL or "." and loss of connection after
2421 "." specially. They can indicate a problem with the sender address or with
2422 the contents of the message rather than a real error on the connection. These
2423 cases are treated in the same way as a 4xx response. This next bit of code
2424 does the classification. */
2435 message_error = TRUE;
2439 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
2440 Ustrncmp(smtp_command,"end ",4) == 0;
2443 case ERRNO_SMTPCLOSED:
2444 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
2448 message_error = FALSE;
2452 /* Handle the cases that are treated as message errors. These are:
2454 (a) negative response or timeout after MAIL
2455 (b) negative response after DATA
2456 (c) negative response or timeout or dropped connection after "."
2458 It won't be a negative response or timeout after RCPT, as that is dealt
2459 with separately above. The action in all cases is to set an appropriate
2460 error code for all the addresses, but to leave yield set to OK because the
2461 host itself has not failed. Of course, it might in practice have failed
2462 when we've had a timeout, but if so, we'll discover that at the next
2463 delivery attempt. For a temporary error, set the message_defer flag, and
2464 write to the logs for information if this is not the last host. The error
2465 for the last host will be logged as part of the address's log line. */
2469 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
2470 set_errno(addrlist, save_errno, message, (code == '5')? FAIL : DEFER,
2471 pass_message, host);
2473 /* If there's an errno, the message contains just the identity of
2476 if (code != '5') /* Anything other than 5 is treated as temporary */
2479 message = US string_sprintf("%s: %s", message, strerror(save_errno));
2480 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
2481 msglog_line(host, message);
2482 *message_defer = TRUE;
2486 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
2487 ".", or some other transportation error. We defer all addresses and yield
2488 DEFER, except for the case of failed add_headers expansion, or a transport
2489 filter failure, when the yield should be ERROR, to stop it trying other
2494 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
2495 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
2496 set_errno(addrlist, save_errno, message, DEFER, pass_message, host);
2502 /* If all has gone well, send_quit will be set TRUE, implying we can end the
2503 SMTP session tidily. However, if there were too many addresses to send in one
2504 message (indicated by first_addr being non-NULL) we want to carry on with the
2505 rest of them. Also, it is desirable to send more than one message down the SMTP
2506 connection if there are several waiting, provided we haven't already sent so
2507 many as to hit the configured limit. The function transport_check_waiting looks
2508 for a waiting message and returns its id. Then transport_pass_socket tries to
2509 set up a continued delivery by passing the socket on to another process. The
2510 variable send_rset is FALSE if a message has just been successfully transfered.
2512 If we are already sending down a continued channel, there may be further
2513 addresses not yet delivered that are aimed at the same host, but which have not
2514 been passed in this run of the transport. In this case, continue_more will be
2515 true, and all we should do is send RSET if necessary, and return, leaving the
2518 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
2519 do not want to continue with other messages down the same channel, because that
2520 can lead to looping between two or more messages, all with the same,
2521 temporarily failing address(es). [The retry information isn't updated yet, so
2522 new processes keep on trying.] We probably also don't want to try more of this
2523 message's addresses either.
2525 If we have started a TLS session, we have to end it before passing the
2526 connection to a new process. However, not all servers can handle this (Exim
2527 can), so we do not pass such a connection on if the host matches
2528 hosts_nopass_tls. */
2531 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
2532 "yield=%d first_address is %sNULL\n", ok, send_quit, send_rset,
2533 continue_more, yield, (first_addr == NULL)? "":"not ");
2535 if (completed_address && ok && send_quit)
2538 if (first_addr != NULL || continue_more ||
2540 (tls_out.active < 0 ||
2541 verify_check_this_host(&(ob->hosts_nopass_tls), NULL, host->name,
2542 host->address, NULL) != OK)
2544 transport_check_waiting(tblock->name, host->name,
2545 tblock->connection_max_messages, new_message_id, &more)
2553 if (! (ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
2555 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
2556 host->address, strerror(save_errno));
2559 else if (! (ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2560 ob->command_timeout)))
2563 send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
2567 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
2568 host->name, host->address, msg);
2573 /* Either RSET was not needed, or it succeeded */
2577 if (first_addr != NULL) /* More addresses still to be sent */
2578 { /* in this run of the transport */
2579 continue_sequence++; /* Causes * in logging */
2582 if (continue_more) return yield; /* More addresses for another run */
2584 /* Pass the socket to a new Exim process. Before doing so, we must shut
2585 down TLS. Not all MTAs allow for the continuation of the SMTP session
2586 when TLS is shut down. We test for this by sending a new EHLO. If we
2587 don't get a good response, we don't attempt to pass the socket on. */
2590 if (tls_out.active >= 0)
2592 tls_close(FALSE, TRUE);
2596 ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
2597 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2598 ob->command_timeout);
2602 /* If the socket is successfully passed, we musn't send QUIT (or
2603 indeed anything!) from here. */
2605 if (ok && transport_pass_socket(tblock->name, host->name, host->address,
2606 new_message_id, inblock.sock))
2612 /* If RSET failed and there are addresses left, they get deferred. */
2614 else set_errno(first_addr, errno, msg, DEFER, FALSE, host);
2618 /* End off tidily with QUIT unless the connection has died or the socket has
2619 been passed to another process. There has been discussion on the net about what
2620 to do after sending QUIT. The wording of the RFC suggests that it is necessary
2621 to wait for a response, but on the other hand, there isn't anything one can do
2622 with an error response, other than log it. Exim used to do that. However,
2623 further discussion suggested that it is positively advantageous not to wait for
2624 the response, but to close the session immediately. This is supposed to move
2625 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
2626 load from the server. (Hosts that are both servers and clients may not see much
2627 difference, of course.) Further discussion indicated that this was safe to do
2628 on Unix systems which have decent implementations of TCP/IP that leave the
2629 connection around for a while (TIME_WAIT) after the application has gone away.
2630 This enables the response sent by the server to be properly ACKed rather than
2631 timed out, as can happen on broken TCP/IP implementations on other OS.
2633 This change is being made on 31-Jul-98. After over a year of trouble-free
2634 operation, the old commented-out code was removed on 17-Sep-99. */
2637 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2642 tls_close(FALSE, TRUE);
2645 /* Close the socket, and return the appropriate value, first setting
2646 works because the NULL setting is passed back to the calling process, and
2647 remote_max_parallel is forced to 1 when delivering over an existing connection,
2649 If all went well and continue_more is set, we shouldn't actually get here if
2650 there are further addresses, as the return above will be taken. However,
2651 writing RSET might have failed, or there may be other addresses whose hosts are
2652 specified in the transports, and therefore not visible at top level, in which
2653 case continue_more won't get set. */
2655 (void)close(inblock.sock);
2657 #ifdef EXPERIMENTAL_EVENT
2658 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
2661 continue_transport = NULL;
2662 continue_hostname = NULL;
2669 /*************************************************
2670 * Closedown entry point *
2671 *************************************************/
2673 /* This function is called when exim is passed an open smtp channel
2674 from another incarnation, but the message which it has been asked
2675 to deliver no longer exists. The channel is on stdin.
2677 We might do fancy things like looking for another message to send down
2678 the channel, but if the one we sought has gone, it has probably been
2679 delivered by some other process that itself will seek further messages,
2680 so just close down our connection.
2682 Argument: pointer to the transport instance block
2687 smtp_transport_closedown(transport_instance *tblock)
2689 smtp_transport_options_block *ob =
2690 (smtp_transport_options_block *)(tblock->options_block);
2691 smtp_inblock inblock;
2692 smtp_outblock outblock;
2694 uschar inbuffer[4096];
2695 uschar outbuffer[16];
2697 inblock.sock = fileno(stdin);
2698 inblock.buffer = inbuffer;
2699 inblock.buffersize = sizeof(inbuffer);
2700 inblock.ptr = inbuffer;
2701 inblock.ptrend = inbuffer;
2703 outblock.sock = inblock.sock;
2704 outblock.buffersize = sizeof(outbuffer);
2705 outblock.buffer = outbuffer;
2706 outblock.ptr = outbuffer;
2707 outblock.cmd_count = 0;
2708 outblock.authenticating = FALSE;
2710 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2711 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2712 ob->command_timeout);
2713 (void)close(inblock.sock);
2718 /*************************************************
2719 * Prepare addresses for delivery *
2720 *************************************************/
2722 /* This function is called to flush out error settings from previous delivery
2723 attempts to other hosts. It also records whether we got here via an MX record
2724 or not in the more_errno field of the address. We are interested only in
2725 addresses that are still marked DEFER - others may have got delivered to a
2726 previously considered IP address. Set their status to PENDING_DEFER to indicate
2727 which ones are relevant this time.
2730 addrlist the list of addresses
2731 host the host we are delivering to
2733 Returns: the first address for this delivery
2736 static address_item *
2737 prepare_addresses(address_item *addrlist, host_item *host)
2739 address_item *first_addr = NULL;
2741 for (addr = addrlist; addr != NULL; addr = addr->next)
2743 if (addr->transport_return != DEFER) continue;
2744 if (first_addr == NULL) first_addr = addr;
2745 addr->transport_return = PENDING_DEFER;
2746 addr->basic_errno = 0;
2747 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
2748 addr->message = NULL;
2750 addr->cipher = NULL;
2751 addr->ourcert = NULL;
2752 addr->peercert = NULL;
2753 addr->peerdn = NULL;
2754 addr->ocsp = OCSP_NOT_REQ;
2762 /*************************************************
2763 * Main entry point *
2764 *************************************************/
2766 /* See local README for interface details. As this is a remote transport, it is
2767 given a chain of addresses to be delivered in one connection, if possible. It
2768 always returns TRUE, indicating that each address has its own independent
2769 status set, except if there is a setting up problem, in which case it returns
2773 smtp_transport_entry(
2774 transport_instance *tblock, /* data for this instantiation */
2775 address_item *addrlist) /* addresses we are working on */
2779 int hosts_defer = 0;
2781 int hosts_looked_up = 0;
2782 int hosts_retry = 0;
2783 int hosts_serial = 0;
2784 int hosts_total = 0;
2785 int total_hosts_tried = 0;
2787 BOOL expired = TRUE;
2788 BOOL continuing = continue_hostname != NULL;
2789 uschar *expanded_hosts = NULL;
2791 uschar *tid = string_sprintf("%s transport", tblock->name);
2792 smtp_transport_options_block *ob =
2793 (smtp_transport_options_block *)(tblock->options_block);
2794 host_item *hostlist = addrlist->host_list;
2795 host_item *host = NULL;
2799 debug_printf("%s transport entered\n", tblock->name);
2800 for (addr = addrlist; addr != NULL; addr = addr->next)
2801 debug_printf(" %s\n", addr->address);
2802 if (continuing) debug_printf("already connected to %s [%s]\n",
2803 continue_hostname, continue_host_address);
2806 /* Set the flag requesting that these hosts be added to the waiting
2807 database if the delivery fails temporarily or if we are running with
2808 queue_smtp or a 2-stage queue run. This gets unset for certain
2809 kinds of error, typically those that are specific to the message. */
2811 update_waiting = TRUE;
2813 /* If a host list is not defined for the addresses - they must all have the
2814 same one in order to be passed to a single transport - or if the transport has
2815 a host list with hosts_override set, use the host list supplied with the
2816 transport. It is an error for this not to exist. */
2818 if (hostlist == NULL || (ob->hosts_override && ob->hosts != NULL))
2820 if (ob->hosts == NULL)
2822 addrlist->message = string_sprintf("%s transport called with no hosts set",
2824 addrlist->transport_return = PANIC;
2825 return FALSE; /* Only top address has status */
2828 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
2831 /* If the transport's host list contains no '$' characters, and we are not
2832 randomizing, it is fixed and therefore a chain of hosts can be built once
2833 and for all, and remembered for subsequent use by other calls to this
2834 transport. If, on the other hand, the host list does contain '$', or we are
2835 randomizing its order, we have to rebuild it each time. In the fixed case,
2836 as the hosts string will never be used again, it doesn't matter that we
2837 replace all the : characters with zeros. */
2839 if (ob->hostlist == NULL)
2841 uschar *s = ob->hosts;
2843 if (Ustrchr(s, '$') != NULL)
2845 if (!(expanded_hosts = expand_string(s)))
2847 addrlist->message = string_sprintf("failed to expand list of hosts "
2848 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
2849 addrlist->transport_return = search_find_defer? DEFER : PANIC;
2850 return FALSE; /* Only top address has status */
2852 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
2853 "\"%s\"\n", s, expanded_hosts);
2857 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
2859 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
2861 /* Check that the expansion yielded something useful. */
2862 if (hostlist == NULL)
2865 string_sprintf("%s transport has empty hosts setting", tblock->name);
2866 addrlist->transport_return = PANIC;
2867 return FALSE; /* Only top address has status */
2870 /* If there was no expansion of hosts, save the host list for
2873 if (!expanded_hosts) ob->hostlist = hostlist;
2876 /* This is not the first time this transport has been run in this delivery;
2877 the host list was built previously. */
2879 else hostlist = ob->hostlist;
2882 /* The host list was supplied with the address. If hosts_randomize is set, we
2883 must sort it into a random order if it did not come from MX records and has not
2884 already been randomized (but don't bother if continuing down an existing
2887 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continuing)
2889 host_item *newlist = NULL;
2890 while (hostlist != NULL)
2892 host_item *h = hostlist;
2893 hostlist = hostlist->next;
2895 h->sort_key = random_number(100);
2897 if (newlist == NULL)
2902 else if (h->sort_key < newlist->sort_key)
2909 host_item *hh = newlist;
2910 while (hh->next != NULL)
2912 if (h->sort_key < hh->next->sort_key) break;
2920 hostlist = addrlist->host_list = newlist;
2924 /* Sort out the default port. */
2926 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
2929 /* For each host-plus-IP-address on the list:
2931 . If this is a continued delivery and the host isn't the one with the
2932 current connection, skip.
2934 . If the status is unusable (i.e. previously failed or retry checked), skip.
2936 . If no IP address set, get the address, either by turning the name into
2937 an address, calling gethostbyname if gethostbyname is on, or by calling
2938 the DNS. The DNS may yield multiple addresses, in which case insert the
2939 extra ones into the list.
2941 . Get the retry data if not previously obtained for this address and set the
2942 field which remembers the state of this address. Skip if the retry time is
2943 not reached. If not, remember whether retry data was found. The retry string
2944 contains both the name and the IP address.
2946 . Scan the list of addresses and mark those whose status is DEFER as
2947 PENDING_DEFER. These are the only ones that will be processed in this cycle
2950 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
2951 Some addresses may be successfully delivered, others may fail, and yet
2952 others may get temporary errors and so get marked DEFER.
2954 . The return from the delivery attempt is OK if a connection was made and a
2955 valid SMTP dialogue was completed. Otherwise it is DEFER.
2957 . If OK, add a "remove" retry item for this host/IPaddress, if any.
2959 . If fail to connect, or other defer state, add a retry item.
2961 . If there are any addresses whose status is still DEFER, carry on to the
2962 next host/IPaddress, unless we have tried the number of hosts given
2963 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
2964 there is some fancy logic for hosts_max_try that means its limit can be
2965 overstepped in some circumstances.
2967 If we get to the end of the list, all hosts have deferred at least one address,
2968 or not reached their retry times. If delay_after_cutoff is unset, it requests a
2969 delivery attempt to those hosts whose last try was before the arrival time of
2970 the current message. To cope with this, we have to go round the loop a second
2971 time. After that, set the status and error data for any addresses that haven't
2972 had it set already. */
2974 for (cutoff_retry = 0; expired &&
2975 cutoff_retry < ((ob->delay_after_cutoff)? 1 : 2);
2978 host_item *nexthost = NULL;
2979 int unexpired_hosts_tried = 0;
2981 for (host = hostlist;
2983 unexpired_hosts_tried < ob->hosts_max_try &&
2984 total_hosts_tried < ob->hosts_max_try_hardlimit;
2990 BOOL serialized = FALSE;
2991 BOOL host_is_expired = FALSE;
2992 BOOL message_defer = FALSE;
2993 BOOL ifchanges = FALSE;
2994 BOOL some_deferred = FALSE;
2995 address_item *first_addr = NULL;
2996 uschar *interface = NULL;
2997 uschar *retry_host_key = NULL;
2998 uschar *retry_message_key = NULL;
2999 uschar *serialize_key = NULL;
3001 /* Default next host is next host. :-) But this can vary if the
3002 hosts_max_try limit is hit (see below). It may also be reset if a host
3003 address is looked up here (in case the host was multihomed). */
3005 nexthost = host->next;
3007 /* If the address hasn't yet been obtained from the host name, look it up
3008 now, unless the host is already marked as unusable. If it is marked as
3009 unusable, it means that the router was unable to find its IP address (in
3010 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
3011 the lookup failed last time. We don't get this far if *all* MX records
3012 point to non-existent hosts; that is treated as a hard error.
3014 We can just skip this host entirely. When the hosts came from the router,
3015 the address will timeout based on the other host(s); when the address is
3016 looked up below, there is an explicit retry record added.
3018 Note that we mustn't skip unusable hosts if the address is not unset; they
3019 may be needed as expired hosts on the 2nd time round the cutoff loop. */
3021 if (host->address == NULL)
3023 int new_port, flags;
3025 uschar *canonical_name;
3027 if (host->status >= hstatus_unusable)
3029 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
3034 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
3036 /* The host name is permitted to have an attached port. Find it, and
3037 strip it from the name. Just remember it for now. */
3039 new_port = host_item_get_port(host);
3041 /* Count hosts looked up */
3045 /* Find by name if so configured, or if it's an IP address. We don't
3046 just copy the IP address, because we need the test-for-local to happen. */
3048 flags = HOST_FIND_BY_A;
3049 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
3050 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
3052 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
3053 rc = host_find_byname(host, NULL, flags, &canonical_name, TRUE);
3055 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
3056 ob->dnssec_request_domains, ob->dnssec_require_domains,
3057 &canonical_name, NULL);
3059 /* Update the host (and any additional blocks, resulting from
3060 multihoming) with a host-specific port, if any. */
3062 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
3064 /* Failure to find the host at this time (usually DNS temporary failure)
3065 is really a kind of routing failure rather than a transport failure.
3066 Therefore we add a retry item of the routing kind, not to stop us trying
3067 to look this name up here again, but to ensure the address gets timed
3068 out if the failures go on long enough. A complete failure at this point
3069 commonly points to a configuration error, but the best action is still
3070 to carry on for the next host. */
3072 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
3074 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
3076 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
3077 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
3078 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
3079 host->status = hstatus_unusable;
3081 for (addr = addrlist; addr != NULL; addr = addr->next)
3083 if (addr->transport_return != DEFER) continue;
3084 addr->basic_errno = ERRNO_UNKNOWNHOST;
3086 string_sprintf("failed to lookup IP address for %s", host->name);
3091 /* If the host is actually the local host, we may have a problem, or
3092 there may be some cunning configuration going on. In the problem case,
3093 log things and give up. The default transport status is already DEFER. */
3095 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
3097 for (addr = addrlist; addr != NULL; addr = addr->next)
3099 addr->basic_errno = 0;
3100 addr->message = string_sprintf("%s transport found host %s to be "
3101 "local", tblock->name, host->name);
3105 } /* End of block for IP address lookup */
3107 /* If this is a continued delivery, we are interested only in the host
3108 which matches the name of the existing open channel. The check is put
3109 here after the local host lookup, in case the name gets expanded as a
3110 result of the lookup. Set expired FALSE, to save the outer loop executing
3113 if (continuing && (Ustrcmp(continue_hostname, host->name) != 0 ||
3114 Ustrcmp(continue_host_address, host->address) != 0))
3117 continue; /* With next host */
3120 /* Reset the default next host in case a multihomed host whose addresses
3121 are not looked up till just above added to the host list. */
3123 nexthost = host->next;
3125 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
3126 domain is in queue_smtp_domains, we don't actually want to attempt any
3127 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
3128 there is a lookup defer in queue_smtp_domains, proceed as if the domain
3129 were not in it. We don't want to hold up all SMTP deliveries! Except when
3130 doing a two-stage queue run, don't do this if forcing. */
3132 if ((!deliver_force || queue_2stage) && (queue_smtp ||
3133 match_isinlist(addrlist->domain, &queue_smtp_domains, 0,
3134 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
3137 for (addr = addrlist; addr != NULL; addr = addr->next)
3139 if (addr->transport_return != DEFER) continue;
3140 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
3142 continue; /* With next host */
3145 /* Count hosts being considered - purely for an intelligent comment
3146 if none are usable. */
3150 /* Set $host and $host address now in case they are needed for the
3151 interface expansion or the serialize_hosts check; they remain set if an
3152 actual delivery happens. */
3154 deliver_host = host->name;
3155 deliver_host_address = host->address;
3156 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
3157 : host->dnssec == DS_NO ? US"no"
3160 /* Set up a string for adding to the retry key if the port number is not
3161 the standard SMTP port. A host may have its own port setting that overrides
3164 pistring = string_sprintf(":%d", (host->port == PORT_NONE)?
3166 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
3168 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
3169 string changes upon expansion, we must add it to the key that is used for
3170 retries, because connections to the same host from a different interface
3171 should be treated separately. */
3173 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET : AF_INET6;
3174 if (!smtp_get_interface(ob->interface, host_af, addrlist, &ifchanges,
3177 if (ifchanges) pistring = string_sprintf("%s/%s", pistring, interface);
3179 /* The first time round the outer loop, check the status of the host by
3180 inspecting the retry data. The second time round, we are interested only
3181 in expired hosts that haven't been tried since this message arrived. */
3183 if (cutoff_retry == 0)
3186 /* Ensure the status of the address is set by checking retry data if
3187 necessary. There may be host-specific retry data (applicable to all
3188 messages) and also data for retries of a specific message at this host.
3189 If either of these retry records are actually read, the keys used are
3190 returned to save recomputing them later. */
3192 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3193 US"retry_include_ip_address", ob->retry_include_ip_address,
3194 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3195 continue; /* with next host */
3197 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
3198 incl_ip, &retry_host_key, &retry_message_key);
3200 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
3201 (host->address == NULL)? US"" : host->address, pistring,
3202 (host->status == hstatus_usable)? "usable" :
3203 (host->status == hstatus_unusable)? "unusable" :
3204 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
3206 /* Skip this address if not usable at this time, noting if it wasn't
3207 actually expired, both locally and in the address. */
3209 switch (host->status)
3211 case hstatus_unusable:
3213 setflag(addrlist, af_retry_skipped);
3216 case hstatus_unusable_expired:
3219 case hwhy_retry: hosts_retry++; break;
3220 case hwhy_failed: hosts_fail++; break;
3221 case hwhy_deferred: hosts_defer++; break;
3224 /* If there was a retry message key, implying that previously there
3225 was a message-specific defer, we don't want to update the list of
3226 messages waiting for these hosts. */
3228 if (retry_message_key != NULL) update_waiting = FALSE;
3229 continue; /* With the next host or IP address */
3233 /* Second time round the loop: if the address is set but expired, and
3234 the message is newer than the last try, let it through. */
3238 if (host->address == NULL ||
3239 host->status != hstatus_unusable_expired ||
3240 host->last_try > received_time)
3243 debug_printf("trying expired host %s [%s]%s\n",
3244 host->name, host->address, pistring);
3245 host_is_expired = TRUE;
3248 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
3249 it remains TRUE only if all hosts are expired and none are actually tried.
3254 /* If this host is listed as one to which access must be serialized,
3255 see if another Exim process has a connection to it, and if so, skip
3256 this host. If not, update the database to record our connection to it
3257 and remember this for later deletion. Do not do any of this if we are
3258 sending the message down a pre-existing connection. */
3261 verify_check_this_host(&(ob->serialize_hosts), NULL, host->name,
3262 host->address, NULL) == OK)
3264 serialize_key = string_sprintf("host-serialize-%s", host->name);
3265 if (!enq_start(serialize_key))
3268 debug_printf("skipping host %s because another Exim process "
3269 "is connected to it\n", host->name);
3276 /* OK, we have an IP address that is not waiting for its retry time to
3277 arrive (it might be expired) OR (second time round the loop) we have an
3278 expired host that hasn't been tried since the message arrived. Have a go
3279 at delivering the message to it. First prepare the addresses by flushing
3280 out the result of previous attempts, and finding the first address that
3281 is still to be delivered. */
3283 first_addr = prepare_addresses(addrlist, host);
3285 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
3286 message_id, host->name, host->address, addrlist->address,
3287 (addrlist->next == NULL)? "" : ", ...");
3289 set_process_info("delivering %s to %s [%s] (%s%s)",
3290 message_id, host->name, host->address, addrlist->address,
3291 (addrlist->next == NULL)? "" : ", ...");
3293 /* This is not for real; don't do the delivery. If there are
3294 any remaining hosts, list them. */
3299 set_errno(addrlist, 0, NULL, OK, FALSE, NULL);
3300 for (addr = addrlist; addr != NULL; addr = addr->next)
3302 addr->host_used = host;
3303 addr->special_action = '*';
3304 addr->message = US"delivery bypassed by -N option";
3308 debug_printf("*** delivery by %s transport bypassed by -N option\n"
3309 "*** host and remaining hosts:\n", tblock->name);
3310 for (host2 = host; host2 != NULL; host2 = host2->next)
3311 debug_printf(" %s [%s]\n", host2->name,
3312 (host2->address == NULL)? US"unset" : host2->address);
3317 /* This is for real. If the host is expired, we don't count it for
3318 hosts_max_retry. This ensures that all hosts must expire before an address
3319 is timed out, unless hosts_max_try_hardlimit (which protects against
3320 lunatic DNS configurations) is reached.
3322 If the host is not expired and we are about to hit the hosts_max_retry
3323 limit, check to see if there is a subsequent hosts with a different MX
3324 value. If so, make that the next host, and don't count this one. This is a
3325 heuristic to make sure that different MXs do get tried. With a normal kind
3326 of retry rule, they would get tried anyway when the earlier hosts were
3327 delayed, but if the domain has a "retry every time" type of rule - as is
3328 often used for the the very large ISPs, that won't happen. */
3333 /* Make a copy of the host if it is local to this invocation
3334 of the transport. */
3338 thost = store_get(sizeof(host_item));
3340 thost->name = string_copy(host->name);
3341 thost->address = string_copy(host->address);
3346 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
3350 debug_printf("hosts_max_try limit reached with this host\n");
3351 for (h = host; h != NULL; h = h->next)
3352 if (h->mx != host->mx) break;
3356 unexpired_hosts_tried--;
3357 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
3358 "and will be tried\n");
3362 /* Attempt the delivery. */
3364 total_hosts_tried++;
3365 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
3366 &message_defer, FALSE);
3369 OK => connection made, each address contains its result;
3370 message_defer is set for message-specific defers (when all
3371 recipients are marked defer)
3372 DEFER => there was a non-message-specific delivery problem;
3373 ERROR => there was a problem setting up the arguments for a filter,
3374 or there was a problem with expanding added headers
3377 /* If the result is not OK, there was a non-message-specific problem.
3378 If the result is DEFER, we need to write to the logs saying what happened
3379 for this particular host, except in the case of authentication and TLS
3380 failures, where the log has already been written. If all hosts defer a
3381 general message is written at the end. */
3383 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL &&
3384 first_addr->basic_errno != ERRNO_TLSFAILURE)
3385 write_logs(first_addr, host);
3387 #ifdef EXPERIMENTAL_EVENT
3389 deferred_event_raise(first_addr, host);
3392 /* If STARTTLS was accepted, but there was a failure in setting up the
3393 TLS session (usually a certificate screwup), and the host is not in
3394 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
3395 TLS forcibly turned off. We have to start from scratch with a new SMTP
3396 connection. That's why the retry is done from here, not from within
3397 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
3398 session, so the in-clear transmission after those errors, if permitted,
3399 happens inside smtp_deliver().] */
3403 && first_addr->basic_errno == ERRNO_TLSFAILURE
3404 && ob->tls_tempfail_tryclear
3405 && verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
3406 host->address, NULL) != OK
3409 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
3410 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
3411 first_addr = prepare_addresses(addrlist, host);
3412 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
3413 &message_defer, TRUE);
3414 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
3415 write_logs(first_addr, host);
3416 # ifdef EXPERIMENTAL_EVENT
3418 deferred_event_raise(first_addr, host);
3421 #endif /*SUPPORT_TLS*/
3424 /* Delivery attempt finished */
3426 rs = (rc == OK)? US"OK" : (rc == DEFER)? US"DEFER" : (rc == ERROR)?
3429 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
3430 message_id, host->name, host->address, addrlist->address,
3431 (addrlist->next == NULL)? "" : " (& others)", rs);
3433 /* Release serialization if set up */
3435 if (serialized) enq_end(serialize_key);
3437 /* If the result is DEFER, or if a host retry record is known to exist, we
3438 need to add an item to the retry chain for updating the retry database
3439 at the end of delivery. We only need to add the item to the top address,
3440 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
3441 for any other delivery attempts using the same address. (It is copied into
3442 the unusable tree at the outer level, so even if different address blocks
3443 contain the same address, it still won't get tried again.) */
3445 if (rc == DEFER || retry_host_key != NULL)
3447 int delete_flag = (rc != DEFER)? rf_delete : 0;
3448 if (retry_host_key == NULL)
3451 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3452 US"retry_include_ip_address", ob->retry_include_ip_address,
3453 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3454 incl_ip = TRUE; /* error; use most-specific retry record */
3456 retry_host_key = incl_ip ?
3457 string_sprintf("T:%S:%s%s", host->name, host->address, pistring) :
3458 string_sprintf("T:%S%s", host->name, pistring);
3461 /* If a delivery of another message over an existing SMTP connection
3462 yields DEFER, we do NOT set up retry data for the host. This covers the
3463 case when there are delays in routing the addresses in the second message
3464 that are so long that the server times out. This is alleviated by not
3465 routing addresses that previously had routing defers when handling an
3466 existing connection, but even so, this case may occur (e.g. if a
3467 previously happily routed address starts giving routing defers). If the
3468 host is genuinely down, another non-continued message delivery will
3469 notice it soon enough. */
3471 if (delete_flag != 0 || !continuing)
3472 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
3474 /* We may have tried an expired host, if its retry time has come; ensure
3475 the status reflects the expiry for the benefit of any other addresses. */
3479 host->status = (host_is_expired)?
3480 hstatus_unusable_expired : hstatus_unusable;
3481 host->why = hwhy_deferred;
3485 /* If message_defer is set (host was OK, but every recipient got deferred
3486 because of some message-specific problem), or if that had happened
3487 previously so that a message retry key exists, add an appropriate item
3488 to the retry chain. Note that if there was a message defer but now there is
3489 a host defer, the message defer record gets deleted. That seems perfectly
3490 reasonable. Also, stop the message from being remembered as waiting
3491 for specific hosts. */
3493 if (message_defer || retry_message_key != NULL)
3495 int delete_flag = message_defer? 0 : rf_delete;
3496 if (retry_message_key == NULL)
3499 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3500 US"retry_include_ip_address", ob->retry_include_ip_address,
3501 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3502 incl_ip = TRUE; /* error; use most-specific retry record */
3504 retry_message_key = incl_ip ?
3505 string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
3507 string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
3509 retry_add_item(addrlist, retry_message_key,
3510 rf_message | rf_host | delete_flag);
3511 update_waiting = FALSE;
3514 /* Any return other than DEFER (that is, OK or ERROR) means that the
3515 addresses have got their final statuses filled in for this host. In the OK
3516 case, see if any of them are deferred. */
3520 for (addr = addrlist; addr != NULL; addr = addr->next)
3522 if (addr->transport_return == DEFER)
3524 some_deferred = TRUE;
3530 /* If no addresses deferred or the result was ERROR, return. We do this for
3531 ERROR because a failing filter set-up or add_headers expansion is likely to
3532 fail for any host we try. */
3534 if (rc == ERROR || (rc == OK && !some_deferred))
3536 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3537 return TRUE; /* Each address has its status */
3540 /* If the result was DEFER or some individual addresses deferred, let
3541 the loop run to try other hosts with the deferred addresses, except for the
3542 case when we were trying to deliver down an existing channel and failed.
3543 Don't try any other hosts in this case. */
3545 if (continuing) break;
3547 /* If the whole delivery, or some individual addresses, were deferred and
3548 there are more hosts that could be tried, do not count this host towards
3549 the hosts_max_try limit if the age of the message is greater than the
3550 maximum retry time for this host. This means we may try try all hosts,
3551 ignoring the limit, when messages have been around for some time. This is
3552 important because if we don't try all hosts, the address will never time
3553 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
3555 if ((rc == DEFER || some_deferred) && nexthost != NULL)
3558 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
3560 if (retry != NULL && retry->rules != NULL)
3562 retry_rule *last_rule;
3563 for (last_rule = retry->rules;
3564 last_rule->next != NULL;
3565 last_rule = last_rule->next);
3566 timedout = time(NULL) - received_time > last_rule->timeout;
3568 else timedout = TRUE; /* No rule => timed out */
3572 unexpired_hosts_tried--;
3573 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
3574 "hosts_max_try (message older than host's retry time)\n");
3577 } /* End of loop for trying multiple hosts. */
3579 /* This is the end of the loop that repeats iff expired is TRUE and
3580 ob->delay_after_cutoff is FALSE. The second time round we will
3581 try those hosts that haven't been tried since the message arrived. */
3585 debug_printf("all IP addresses skipped or deferred at least one address\n");
3586 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
3587 debug_printf("retrying IP addresses not tried since message arrived\n");
3592 /* Get here if all IP addresses are skipped or defer at least one address. In
3593 MUA wrapper mode, this will happen only for connection or other non-message-
3594 specific failures. Force the delivery status for all addresses to FAIL. */
3598 for (addr = addrlist; addr != NULL; addr = addr->next)
3599 addr->transport_return = FAIL;
3603 /* In the normal, non-wrapper case, add a standard message to each deferred
3604 address if there hasn't been an error, that is, if it hasn't actually been
3605 tried this time. The variable "expired" will be FALSE if any deliveries were
3606 actually tried, or if there was at least one host that was not expired. That
3607 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
3608 a delivery has been tried, an error code will be set, and the failing of the
3609 message is handled by the retry code later.
3611 If queue_smtp is set, or this transport was called to send a subsequent message
3612 down an existing TCP/IP connection, and something caused the host not to be
3613 found, we end up here, but can detect these cases and handle them specially. */
3615 for (addr = addrlist; addr != NULL; addr = addr->next)
3617 /* If host is not NULL, it means that we stopped processing the host list
3618 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
3619 means we need to behave as if some hosts were skipped because their retry
3620 time had not come. Specifically, this prevents the address from timing out.
3621 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
3622 hosts were tried. */
3626 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
3629 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
3630 "hosts were tried\n");
3635 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
3636 setflag(addr, af_retry_skipped);
3640 if (queue_smtp) /* no deliveries attempted */
3642 addr->transport_return = DEFER;
3643 addr->basic_errno = 0;
3644 addr->message = US"SMTP delivery explicitly queued";
3647 else if (addr->transport_return == DEFER &&
3648 (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0) &&
3649 addr->message == NULL)
3651 addr->basic_errno = ERRNO_HRETRY;
3652 if (continue_hostname != NULL)
3654 addr->message = US"no host found for existing SMTP connection";
3658 setflag(addr, af_pass_message); /* This is not a security risk */
3659 addr->message = (ob->delay_after_cutoff)?
3660 US"retry time not reached for any host after a long failure period" :
3661 US"all hosts have been failing for a long time and were last tried "
3662 "after this message arrived";
3664 /* If we are already using fallback hosts, or there are no fallback hosts
3665 defined, convert the result to FAIL to cause a bounce. */
3667 if (addr->host_list == addr->fallback_hosts ||
3668 addr->fallback_hosts == NULL)
3669 addr->transport_return = FAIL;
3673 if (hosts_retry == hosts_total)
3674 addr->message = US"retry time not reached for any host";
3675 else if (hosts_fail == hosts_total)
3676 addr->message = US"all host address lookups failed permanently";
3677 else if (hosts_defer == hosts_total)
3678 addr->message = US"all host address lookups failed temporarily";
3679 else if (hosts_serial == hosts_total)
3680 addr->message = US"connection limit reached for all hosts";
3681 else if (hosts_fail+hosts_defer == hosts_total)
3682 addr->message = US"all host address lookups failed";
3683 else addr->message = US"some host address lookups failed and retry time "
3684 "not reached for other hosts or connection limit reached";
3689 /* Update the database which keeps information about which messages are waiting
3690 for which hosts to become available. For some message-specific errors, the
3691 update_waiting flag is turned off because we don't want follow-on deliveries in
3692 those cases. If this transport instance is explicitly limited to one message
3693 per connection then follow-on deliveries are not possible and there's no need
3694 to create/update the per-transport wait-<transport_name> database. */
3696 if (update_waiting && tblock->connection_max_messages != 1)
3697 transport_update_waiting(hostlist, tblock->name);
3701 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3703 return TRUE; /* Each address has its status */
3708 /* End of transport/smtp.c */
git://git.exim.org / exim.git / blob