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_multi_domain", opt_stringptr | opt_hidden | opt_public,
23 (void *)offsetof(transport_instance, expand_multi_domain) },
24 { "*expand_retry_include_ip_address", opt_stringptr | opt_hidden,
25 (void *)(offsetof(smtp_transport_options_block, expand_retry_include_ip_address)) },
27 { "address_retry_include_sender", opt_bool,
28 (void *)offsetof(smtp_transport_options_block, address_retry_include_sender) },
29 { "allow_localhost", opt_bool,
30 (void *)offsetof(smtp_transport_options_block, allow_localhost) },
31 { "authenticated_sender", opt_stringptr,
32 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
33 { "authenticated_sender_force", opt_bool,
34 (void *)offsetof(smtp_transport_options_block, authenticated_sender_force) },
35 { "command_timeout", opt_time,
36 (void *)offsetof(smtp_transport_options_block, command_timeout) },
37 { "connect_timeout", opt_time,
38 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
39 { "connection_max_messages", opt_int | opt_public,
40 (void *)offsetof(transport_instance, connection_max_messages) },
41 { "data_timeout", opt_time,
42 (void *)offsetof(smtp_transport_options_block, data_timeout) },
43 { "delay_after_cutoff", opt_bool,
44 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
46 { "dkim_canon", opt_stringptr,
47 (void *)offsetof(smtp_transport_options_block, dkim_canon) },
48 { "dkim_domain", opt_stringptr,
49 (void *)offsetof(smtp_transport_options_block, dkim_domain) },
50 { "dkim_private_key", opt_stringptr,
51 (void *)offsetof(smtp_transport_options_block, dkim_private_key) },
52 { "dkim_selector", opt_stringptr,
53 (void *)offsetof(smtp_transport_options_block, dkim_selector) },
54 { "dkim_sign_headers", opt_stringptr,
55 (void *)offsetof(smtp_transport_options_block, dkim_sign_headers) },
56 { "dkim_strict", opt_stringptr,
57 (void *)offsetof(smtp_transport_options_block, dkim_strict) },
59 { "dns_qualify_single", opt_bool,
60 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
61 { "dns_search_parents", opt_bool,
62 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
63 { "dnssec_request_domains", opt_stringptr,
64 (void *)offsetof(smtp_transport_options_block, dnssec_request_domains) },
65 { "dnssec_require_domains", opt_stringptr,
66 (void *)offsetof(smtp_transport_options_block, dnssec_require_domains) },
67 { "dscp", opt_stringptr,
68 (void *)offsetof(smtp_transport_options_block, dscp) },
69 { "fallback_hosts", opt_stringptr,
70 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
71 { "final_timeout", opt_time,
72 (void *)offsetof(smtp_transport_options_block, final_timeout) },
73 { "gethostbyname", opt_bool,
74 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
76 /* These are no longer honoured, as of Exim 4.80; for now, we silently
77 ignore; 4.83 will warn, and a later-still release will remove
78 these options, so that using them becomes an error. */
79 { "gnutls_require_kx", opt_stringptr,
80 (void *)offsetof(smtp_transport_options_block, gnutls_require_kx) },
81 { "gnutls_require_mac", opt_stringptr,
82 (void *)offsetof(smtp_transport_options_block, gnutls_require_mac) },
83 { "gnutls_require_protocols", opt_stringptr,
84 (void *)offsetof(smtp_transport_options_block, gnutls_require_proto) },
86 { "helo_data", opt_stringptr,
87 (void *)offsetof(smtp_transport_options_block, helo_data) },
88 { "hosts", opt_stringptr,
89 (void *)offsetof(smtp_transport_options_block, hosts) },
90 { "hosts_avoid_esmtp", opt_stringptr,
91 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
92 { "hosts_avoid_pipelining", opt_stringptr,
93 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
95 { "hosts_avoid_tls", opt_stringptr,
96 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
98 { "hosts_max_try", opt_int,
99 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
100 { "hosts_max_try_hardlimit", opt_int,
101 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
103 { "hosts_nopass_tls", opt_stringptr,
104 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
106 { "hosts_override", opt_bool,
107 (void *)offsetof(smtp_transport_options_block, hosts_override) },
108 { "hosts_randomize", opt_bool,
109 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
110 #if defined(SUPPORT_TLS) && !defined(DISABLE_OCSP)
111 { "hosts_request_ocsp", opt_stringptr,
112 (void *)offsetof(smtp_transport_options_block, hosts_request_ocsp) },
114 { "hosts_require_auth", opt_stringptr,
115 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
117 # ifdef EXPERIMENTAL_DANE
118 { "hosts_require_dane", opt_stringptr,
119 (void *)offsetof(smtp_transport_options_block, hosts_require_dane) },
121 # ifndef DISABLE_OCSP
122 { "hosts_require_ocsp", opt_stringptr,
123 (void *)offsetof(smtp_transport_options_block, hosts_require_ocsp) },
125 { "hosts_require_tls", opt_stringptr,
126 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
128 { "hosts_try_auth", opt_stringptr,
129 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
130 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
131 { "hosts_try_dane", opt_stringptr,
132 (void *)offsetof(smtp_transport_options_block, hosts_try_dane) },
135 { "hosts_try_prdr", opt_stringptr,
136 (void *)offsetof(smtp_transport_options_block, hosts_try_prdr) },
139 { "hosts_verify_avoid_tls", opt_stringptr,
140 (void *)offsetof(smtp_transport_options_block, hosts_verify_avoid_tls) },
142 { "interface", opt_stringptr,
143 (void *)offsetof(smtp_transport_options_block, interface) },
144 { "keepalive", opt_bool,
145 (void *)offsetof(smtp_transport_options_block, keepalive) },
146 { "lmtp_ignore_quota", opt_bool,
147 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
148 { "max_rcpt", opt_int | opt_public,
149 (void *)offsetof(transport_instance, max_addresses) },
150 { "multi_domain", opt_expand_bool | opt_public,
151 (void *)offsetof(transport_instance, multi_domain) },
152 { "port", opt_stringptr,
153 (void *)offsetof(smtp_transport_options_block, port) },
154 { "protocol", opt_stringptr,
155 (void *)offsetof(smtp_transport_options_block, protocol) },
156 { "retry_include_ip_address", opt_expand_bool,
157 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
158 { "serialize_hosts", opt_stringptr,
159 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
160 { "size_addition", opt_int,
161 (void *)offsetof(smtp_transport_options_block, size_addition) }
163 ,{ "tls_certificate", opt_stringptr,
164 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
165 { "tls_crl", opt_stringptr,
166 (void *)offsetof(smtp_transport_options_block, tls_crl) },
167 { "tls_dh_min_bits", opt_int,
168 (void *)offsetof(smtp_transport_options_block, tls_dh_min_bits) },
169 { "tls_privatekey", opt_stringptr,
170 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
171 { "tls_require_ciphers", opt_stringptr,
172 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
173 { "tls_sni", opt_stringptr,
174 (void *)offsetof(smtp_transport_options_block, tls_sni) },
175 { "tls_tempfail_tryclear", opt_bool,
176 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
177 { "tls_try_verify_hosts", opt_stringptr,
178 (void *)offsetof(smtp_transport_options_block, tls_try_verify_hosts) },
179 { "tls_verify_cert_hostnames", opt_stringptr,
180 (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 US"*", /* 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 US"system", /* 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 US"*", /* tls_try_verify_hosts */
264 US"*" /* tls_verify_cert_hostnames */
267 ,NULL, /* dkim_canon */
268 NULL, /* dkim_domain */
269 NULL, /* dkim_private_key */
270 NULL, /* dkim_selector */
271 NULL, /* dkim_sign_headers */
272 NULL /* dkim_strict */
276 /* some DSN flags for use later */
278 static int rf_list[] = {rf_notify_never, rf_notify_success,
279 rf_notify_failure, rf_notify_delay };
281 static uschar *rf_names[] = { US"NEVER", US"SUCCESS", US"FAILURE", US"DELAY" };
287 static uschar *smtp_command; /* Points to last cmd for error messages */
288 static uschar *mail_command; /* Points to MAIL cmd for error messages */
289 static BOOL update_waiting; /* TRUE to update the "wait" database */
292 /*************************************************
293 * Setup entry point *
294 *************************************************/
296 /* This function is called when the transport is about to be used,
297 but before running it in a sub-process. It is used for two things:
299 (1) To set the fallback host list in addresses, when delivering.
300 (2) To pass back the interface, port, protocol, and other options, for use
301 during callout verification.
304 tblock pointer to the transport instance block
305 addrlist list of addresses about to be transported
306 tf if not NULL, pointer to block in which to return options
307 uid the uid that will be set (not used)
308 gid the gid that will be set (not used)
309 errmsg place for error message (not used)
311 Returns: OK always (FAIL, DEFER not used)
315 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
316 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
318 smtp_transport_options_block *ob =
319 (smtp_transport_options_block *)(tblock->options_block);
321 errmsg = errmsg; /* Keep picky compilers happy */
325 /* Pass back options if required. This interface is getting very messy. */
329 tf->interface = ob->interface;
331 tf->protocol = ob->protocol;
332 tf->hosts = ob->hosts;
333 tf->hosts_override = ob->hosts_override;
334 tf->hosts_randomize = ob->hosts_randomize;
335 tf->gethostbyname = ob->gethostbyname;
336 tf->qualify_single = ob->dns_qualify_single;
337 tf->search_parents = ob->dns_search_parents;
338 tf->helo_data = ob->helo_data;
341 /* Set the fallback host list for all the addresses that don't have fallback
342 host lists, provided that the local host wasn't present in the original host
345 if (!testflag(addrlist, af_local_host_removed))
347 for (; addrlist != NULL; addrlist = addrlist->next)
348 if (addrlist->fallback_hosts == NULL)
349 addrlist->fallback_hosts = ob->fallback_hostlist;
357 /*************************************************
358 * Initialization entry point *
359 *************************************************/
361 /* Called for each instance, after its options have been read, to
362 enable consistency checks to be done, or anything else that needs
365 Argument: pointer to the transport instance block
370 smtp_transport_init(transport_instance *tblock)
372 smtp_transport_options_block *ob =
373 (smtp_transport_options_block *)(tblock->options_block);
375 /* Retry_use_local_part defaults FALSE if unset */
377 if (tblock->retry_use_local_part == TRUE_UNSET)
378 tblock->retry_use_local_part = FALSE;
380 /* Set the default port according to the protocol */
382 if (ob->port == NULL)
383 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
384 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
386 /* Set up the setup entry point, to be called before subprocesses for this
389 tblock->setup = smtp_transport_setup;
391 /* Complain if any of the timeouts are zero. */
393 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
394 ob->final_timeout <= 0)
395 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
396 "command, data, or final timeout value is zero for %s transport",
399 /* If hosts_override is set and there are local hosts, set the global
400 flag that stops verify from showing router hosts. */
402 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
404 /* If there are any fallback hosts listed, build a chain of host items
405 for them, but do not do any lookups at this time. */
407 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
410 if ( ob->gnutls_require_kx
411 || ob->gnutls_require_mac
412 || ob->gnutls_require_proto)
413 log_write(0, LOG_MAIN, "WARNING: smtp transport options"
414 " gnutls_require_kx, gnutls_require_mac and gnutls_require_protocols"
423 /*************************************************
424 * Set delivery info into all active addresses *
425 *************************************************/
427 /* Only addresses whose status is >= PENDING are relevant. A lesser
428 status means that an address is not currently being processed.
431 addrlist points to a chain of addresses
432 errno_value to put in each address's errno field
433 msg to put in each address's message field
434 rc to put in each address's transport_return field
435 pass_message if TRUE, set the "pass message" flag in the address
436 host if set, mark addrs as having used this host
438 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
439 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
440 this particular type of timeout.
446 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
447 BOOL pass_message, host_item * host)
451 if (errno_value == ERRNO_CONNECTTIMEOUT)
453 errno_value = ETIMEDOUT;
454 orvalue = RTEF_CTOUT;
456 for (addr = addrlist; addr != NULL; addr = addr->next)
457 if (addr->transport_return >= PENDING)
459 addr->basic_errno = errno_value;
460 addr->more_errno |= orvalue;
464 if (pass_message) setflag(addr, af_pass_message);
466 addr->transport_return = rc;
468 addr->host_used = host;
474 /*************************************************
475 * Check an SMTP response *
476 *************************************************/
478 /* This function is given an errno code and the SMTP response buffer
479 to analyse, together with the host identification for generating messages. It
480 sets an appropriate message and puts the first digit of the response code into
481 the yield variable. If no response was actually read, a suitable digit is
485 host the current host, to get its name for messages
486 errno_value pointer to the errno value
487 more_errno from the top address for use with ERRNO_FILTER_FAIL
488 buffer the SMTP response buffer
489 yield where to put a one-digit SMTP response code
490 message where to put an errror message
491 pass_message set TRUE if message is an SMTP response
493 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
497 check_response(host_item *host, int *errno_value, int more_errno,
498 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
502 if (smtp_use_pipelining &&
503 (Ustrcmp(smtp_command, "MAIL") == 0 ||
504 Ustrcmp(smtp_command, "RCPT") == 0 ||
505 Ustrcmp(smtp_command, "DATA") == 0))
508 *yield = '4'; /* Default setting is to give a temporary error */
510 /* Handle response timeout */
512 if (*errno_value == ETIMEDOUT)
514 *message = US string_sprintf("SMTP timeout after %s%s",
516 if (transport_count > 0)
517 *message = US string_sprintf("%s (%d bytes written)", *message,
522 /* Handle malformed SMTP response */
524 if (*errno_value == ERRNO_SMTPFORMAT)
526 uschar *malfresp = string_printing(buffer);
527 while (isspace(*malfresp)) malfresp++;
528 *message = *malfresp == 0
529 ? string_sprintf("Malformed SMTP reply (an empty line) "
530 "in response to %s%s", pl, smtp_command)
531 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
532 pl, smtp_command, malfresp);
536 /* Handle a failed filter process error; can't send QUIT as we mustn't
539 if (*errno_value == ERRNO_FILTER_FAIL)
541 *message = US string_sprintf("transport filter process failed (%d)%s",
543 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
547 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
550 if (*errno_value == ERRNO_CHHEADER_FAIL)
553 US string_sprintf("failed to expand headers_add or headers_remove: %s",
554 expand_string_message);
558 /* Handle failure to write a complete data block */
560 if (*errno_value == ERRNO_WRITEINCOMPLETE)
562 *message = US string_sprintf("failed to write a data block");
566 /* Handle error responses from the remote mailer. */
570 uschar *s = string_printing(buffer);
571 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
572 "%s", pl, smtp_command, s);
573 *pass_message = TRUE;
578 /* No data was read. If there is no errno, this must be the EOF (i.e.
579 connection closed) case, which causes deferral. An explicit connection reset
580 error has the same effect. Otherwise, put the host's identity in the message,
581 leaving the errno value to be interpreted as well. In all cases, we have to
582 assume the connection is now dead. */
584 if (*errno_value == 0 || *errno_value == ECONNRESET)
586 *errno_value = ERRNO_SMTPCLOSED;
587 *message = US string_sprintf("Remote host closed connection "
588 "in response to %s%s", pl, smtp_command);
590 else *message = US string_sprintf("%s [%s]", host->name, host->address);
597 /*************************************************
598 * Write error message to logs *
599 *************************************************/
601 /* This writes to the main log and to the message log.
604 addr the address item containing error information
605 host the current host
611 write_logs(address_item *addr, host_item *host)
613 uschar * message = string_sprintf("H=%s [%s]", host->name, host->address);
617 message = string_sprintf("%s: %s", message, addr->message);
618 if (addr->basic_errno > 0)
619 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
620 log_write(0, LOG_MAIN, "%s", message);
621 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
625 if (log_extra_selector & LX_outgoing_port)
626 message = string_sprintf("%s:%d", message,
627 host->port == PORT_NONE ? 25 : host->port);
628 log_write(0, LOG_MAIN, "%s %s", message, strerror(addr->basic_errno));
629 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), message,
630 strerror(addr->basic_errno));
635 msglog_line(host_item * host, uschar * message)
637 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
638 host->name, host->address, message);
643 #ifdef EXPERIMENTAL_EVENT
644 /*************************************************
645 * Post-defer action *
646 *************************************************/
648 /* This expands an arbitrary per-transport string.
649 It might, for example, be used to write to the database log.
652 addr the address item containing error information
653 host the current host
659 deferred_event_raise(address_item *addr, host_item *host)
661 uschar * action = addr->transport->event_action;
662 uschar * save_domain;
668 save_domain = deliver_domain;
669 save_local = deliver_localpart;
671 /*XXX would ip & port already be set up? */
672 deliver_host_address = string_copy(host->address);
673 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
674 event_defer_errno = addr->basic_errno;
676 router_name = addr->router->name;
677 transport_name = addr->transport->name;
678 deliver_domain = addr->domain;
679 deliver_localpart = addr->local_part;
681 (void) event_raise(action, US"msg:host:defer",
683 ? addr->basic_errno > 0
684 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
685 : string_copy(addr->message)
686 : addr->basic_errno > 0
687 ? string_copy(US strerror(addr->basic_errno))
690 deliver_localpart = save_local;
691 deliver_domain = save_domain;
692 router_name = transport_name = NULL;
698 /*************************************************
699 * Synchronize SMTP responses *
700 *************************************************/
702 /* This function is called from smtp_deliver() to receive SMTP responses from
703 the server, and match them up with the commands to which they relate. When
704 PIPELINING is not in use, this function is called after every command, and is
705 therefore somewhat over-engineered, but it is simpler to use a single scheme
706 that works both with and without PIPELINING instead of having two separate sets
709 The set of commands that are buffered up with pipelining may start with MAIL
710 and may end with DATA; in between are RCPT commands that correspond to the
711 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
712 etc.) are never buffered.
714 Errors after MAIL or DATA abort the whole process leaving the response in the
715 buffer. After MAIL, pending responses are flushed, and the original command is
716 re-instated in big_buffer for error messages. For RCPT commands, the remote is
717 permitted to reject some recipient addresses while accepting others. However
718 certain errors clearly abort the whole process. Set the value in
719 transport_return to PENDING_OK if the address is accepted. If there is a
720 subsequent general error, it will get reset accordingly. If not, it will get
721 converted to OK at the end.
724 addrlist the complete address list
725 include_affixes TRUE if affixes include in RCPT
726 sync_addr ptr to the ptr of the one to start scanning at (updated)
727 host the host we are connected to
728 count the number of responses to read
730 include_sender true if 4xx retry is to include the sender it its key
731 pending_MAIL true if the first response is for MAIL
732 pending_DATA 0 if last command sent was not DATA
733 +1 if previously had a good recipient
734 -1 if not previously had a good recipient
735 inblock incoming SMTP block
736 timeout timeout value
737 buffer buffer for reading response
738 buffsize size of buffer
740 Returns: 3 if at least one address had 2xx and one had 5xx
741 2 if at least one address had 5xx but none had 2xx
742 1 if at least one host had a 2xx response, but none had 5xx
743 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
744 -1 timeout while reading RCPT response
745 -2 I/O or other non-response error for RCPT
746 -3 DATA or MAIL failed - errno and buffer set
750 sync_responses(address_item *addrlist, BOOL include_affixes,
751 address_item **sync_addr, host_item *host, int count,
752 BOOL address_retry_include_sender, BOOL pending_MAIL,
753 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
756 address_item *addr = *sync_addr;
759 /* Handle the response for a MAIL command. On error, reinstate the original
760 command in big_buffer for error message use, and flush any further pending
761 responses before returning, except after I/O errors and timeouts. */
766 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
768 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
769 if (errno == 0 && buffer[0] != 0)
771 uschar flushbuffer[4096];
773 if (buffer[0] == '4')
775 save_errno = ERRNO_MAIL4XX;
776 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
780 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
782 && (errno != 0 || flushbuffer[0] == 0))
788 if (pending_DATA) count--; /* Number of RCPT responses to come */
789 while (count-- > 0) /* Mark any pending addrs with the host used */
791 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
792 addr->host_used = host;
799 if (pending_DATA) count--; /* Number of RCPT responses to come */
801 /* Read and handle the required number of RCPT responses, matching each one up
802 with an address by scanning for the next address whose status is PENDING_DEFER.
807 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
809 /* The address was accepted */
810 addr->host_used = host;
812 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
815 addr->transport_return = PENDING_OK;
817 /* If af_dr_retry_exists is set, there was a routing delay on this address;
818 ensure that any address-specific retry record is expunged. We do this both
819 for the basic key and for the version that also includes the sender. */
821 if (testflag(addr, af_dr_retry_exists))
823 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
825 retry_add_item(addr, altkey, rf_delete);
826 retry_add_item(addr, addr->address_retry_key, rf_delete);
830 /* Timeout while reading the response */
832 else if (errno == ETIMEDOUT)
834 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
835 transport_rcpt_address(addr, include_affixes));
836 set_errno(addrlist, ETIMEDOUT, message, DEFER, FALSE, NULL);
837 retry_add_item(addr, addr->address_retry_key, 0);
838 update_waiting = FALSE;
842 /* Handle other errors in obtaining an SMTP response by returning -1. This
843 will cause all the addresses to be deferred. Restore the SMTP command in
844 big_buffer for which we are checking the response, so the error message
847 else if (errno != 0 || buffer[0] == 0)
849 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
850 transport_rcpt_address(addr, include_affixes));
854 /* Handle SMTP permanent and temporary response codes. */
859 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
860 "%s", transport_rcpt_address(addr, include_affixes),
861 string_printing(buffer));
862 setflag(addr, af_pass_message);
863 msglog_line(host, addr->message);
865 /* The response was 5xx */
867 if (buffer[0] == '5')
869 addr->transport_return = FAIL;
873 /* The response was 4xx */
877 addr->transport_return = DEFER;
878 addr->basic_errno = ERRNO_RCPT4XX;
879 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
881 /* Log temporary errors if there are more hosts to be tried.
882 If not, log this last one in the == line. */
885 log_write(0, LOG_MAIN, "H=%s [%s]: %s", host->name, host->address, addr->message);
887 /* Do not put this message on the list of those waiting for specific
888 hosts, as otherwise it is likely to be tried too often. */
890 update_waiting = FALSE;
892 /* Add a retry item for the address so that it doesn't get tried again
893 too soon. If address_retry_include_sender is true, add the sender address
896 if (address_retry_include_sender)
898 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
900 retry_add_item(addr, altkey, 0);
902 else retry_add_item(addr, addr->address_retry_key, 0);
905 } /* Loop for next RCPT response */
907 /* Update where to start at for the next block of responses, unless we
908 have already handled all the addresses. */
910 if (addr != NULL) *sync_addr = addr->next;
912 /* Handle a response to DATA. If we have not had any good recipients, either
913 previously or in this block, the response is ignored. */
915 if (pending_DATA != 0 &&
916 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
921 if (pending_DATA > 0 || (yield & 1) != 0)
923 if (errno == 0 && buffer[0] == '4')
925 errno = ERRNO_DATA4XX;
926 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
930 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
931 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
932 "is in use and there were no good recipients\n", msg);
935 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
936 present) received 3xx. If any RCPTs were handled and yielded anything other
937 than 4xx, yield will be set non-zero. */
944 /* Do the client side of smtp-level authentication */
947 buffer EHLO response from server (gets overwritten)
948 addrlist chain of potential addresses to deliver
949 host host to deliver to
951 ibp, obp comms channel control blocks
954 OK Success, or failed (but not required): global "smtp_authenticated" set
955 DEFER Failed authentication (and was required)
956 ERROR Internal problem
958 FAIL_SEND Failed communications - transmit
963 smtp_auth(uschar *buffer, unsigned bufsize, address_item *addrlist, host_item *host,
964 smtp_transport_options_block *ob, BOOL is_esmtp,
965 smtp_inblock *ibp, smtp_outblock *obp)
968 uschar *fail_reason = US"server did not advertise AUTH support";
970 smtp_authenticated = FALSE;
971 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
972 require_auth = verify_check_given_host(&ob->hosts_require_auth, host);
974 if (is_esmtp && !regex_AUTH) regex_AUTH =
975 regex_must_compile(US"\\n250[\\s\\-]AUTH\\s+([\\-\\w\\s]+)(?:\\n|$)",
978 if (is_esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
980 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
981 expand_nmax = -1; /* reset */
983 /* Must not do this check until after we have saved the result of the
984 regex match above. */
986 if (require_auth == OK ||
987 verify_check_given_host(&ob->hosts_try_auth, host) == OK)
990 fail_reason = US"no common mechanisms were found";
992 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
994 /* Scan the configured authenticators looking for one which is configured
995 for use as a client, which is not suppressed by client_condition, and
996 whose name matches an authentication mechanism supported by the server.
997 If one is found, attempt to authenticate by calling its client function.
1000 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1004 (au->client_condition != NULL &&
1005 !expand_check_condition(au->client_condition, au->name,
1006 US"client authenticator")))
1008 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1010 (au->client)? "client_condition is false" :
1011 "not configured as a client");
1015 /* Loop to scan supported server mechanisms */
1020 int len = Ustrlen(au->public_name);
1021 while (isspace(*p)) p++;
1023 if (strncmpic(au->public_name, p, len) != 0 ||
1024 (p[len] != 0 && !isspace(p[len])))
1026 while (*p != 0 && !isspace(*p)) p++;
1030 /* Found data for a listed mechanism. Call its client entry. Set
1031 a flag in the outblock so that data is overwritten after sending so
1032 that reflections don't show it. */
1034 fail_reason = US"authentication attempt(s) failed";
1035 obp->authenticating = TRUE;
1036 rc = (au->info->clientcode)(au, ibp, obp,
1037 ob->command_timeout, buffer, bufsize);
1038 obp->authenticating = FALSE;
1039 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1042 /* A temporary authentication failure must hold up delivery to
1043 this host. After a permanent authentication failure, we carry on
1044 to try other authentication methods. If all fail hard, try to
1045 deliver the message unauthenticated unless require_auth was set. */
1050 smtp_authenticated = TRUE; /* stops the outer loop */
1051 client_authenticator = au->name;
1052 if (au->set_client_id != NULL)
1053 client_authenticated_id = expand_string(au->set_client_id);
1056 /* Failure after writing a command */
1061 /* Failure after reading a response */
1064 if (errno != 0 || buffer[0] != '5') return FAIL;
1065 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1066 au->name, host->name, host->address, buffer);
1069 /* Failure by some other means. In effect, the authenticator
1070 decided it wasn't prepared to handle this case. Typically this
1071 is the result of "fail" in an expansion string. Do we need to
1072 log anything here? Feb 2006: a message is now put in the buffer
1073 if logging is required. */
1077 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1078 "authentication H=%s [%s] %s", au->name, host->name,
1079 host->address, buffer);
1082 /* Internal problem, message in buffer. */
1085 set_errno(addrlist, ERRNO_AUTHPROB, string_copy(buffer),
1086 DEFER, FALSE, NULL);
1090 break; /* If not authenticated, try next authenticator */
1091 } /* Loop for scanning supported server mechanisms */
1092 } /* Loop for further authenticators */
1096 /* If we haven't authenticated, but are required to, give up. */
1098 if (require_auth == OK && !smtp_authenticated)
1100 set_errno(addrlist, ERRNO_AUTHFAIL,
1101 string_sprintf("authentication required but %s", fail_reason), DEFER,
1110 /* Construct AUTH appendix string for MAIL TO */
1113 buffer to build string
1114 addrlist chain of potential addresses to deliver
1115 ob transport options
1117 Globals smtp_authenticated
1118 client_authenticated_sender
1119 Return True on error, otherwise buffer has (possibly empty) terminated string
1123 smtp_mail_auth_str(uschar *buffer, unsigned bufsize, address_item *addrlist,
1124 smtp_transport_options_block *ob)
1126 uschar *local_authenticated_sender = authenticated_sender;
1129 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n", authenticated_sender, ob->authenticated_sender, smtp_authenticated?"Y":"N");
1132 if (ob->authenticated_sender != NULL)
1134 uschar *new = expand_string(ob->authenticated_sender);
1137 if (!expand_string_forcedfail)
1139 uschar *message = string_sprintf("failed to expand "
1140 "authenticated_sender: %s", expand_string_message);
1141 set_errno(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, NULL);
1145 else if (new[0] != 0) local_authenticated_sender = new;
1148 /* Add the authenticated sender address if present */
1150 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1151 local_authenticated_sender != NULL)
1153 string_format(buffer, bufsize, " AUTH=%s",
1154 auth_xtextencode(local_authenticated_sender,
1155 Ustrlen(local_authenticated_sender)));
1156 client_authenticated_sender = string_copy(local_authenticated_sender);
1166 #ifdef EXPERIMENTAL_DANE
1168 tlsa_lookup(const host_item * host, dns_answer * dnsa,
1169 BOOL dane_required, BOOL * dane)
1171 /* move this out to host.c given the similarity to dns_lookup() ? */
1173 uschar * fullname = buffer;
1175 /* TLSA lookup string */
1176 (void)sprintf(CS buffer, "_%d._tcp.%.256s", host->port, host->name);
1178 switch (dns_lookup(dnsa, buffer, T_TLSA, &fullname))
1181 return DEFER; /* just defer this TLS'd conn */
1187 log_write(0, LOG_MAIN, "DANE error: TLSA lookup failed");
1193 if (!dns_is_secure(dnsa))
1195 log_write(0, LOG_MAIN, "DANE error: TLSA lookup not DNSSEC");
1206 /*************************************************
1207 * Deliver address list to given host *
1208 *************************************************/
1210 /* If continue_hostname is not null, we get here only when continuing to
1211 deliver down an existing channel. The channel was passed as the standard
1212 input. TLS is never active on a passed channel; the previous process always
1213 closes it down before passing the connection on.
1215 Otherwise, we have to make a connection to the remote host, and do the
1216 initial protocol exchange.
1218 When running as an MUA wrapper, if the sender or any recipient is rejected,
1219 temporarily or permanently, we force failure for all recipients.
1222 addrlist chain of potential addresses to deliver; only those whose
1223 transport_return field is set to PENDING_DEFER are currently
1224 being processed; others should be skipped - they have either
1225 been delivered to an earlier host or IP address, or been
1226 failed by one of them.
1227 host host to deliver to
1228 host_af AF_INET or AF_INET6
1229 port default TCP/IP port to use, in host byte order
1230 interface interface to bind to, or NULL
1231 tblock transport instance block
1232 message_defer set TRUE if yield is OK, but all addresses were deferred
1233 because of a non-recipient, non-host failure, that is, a
1234 4xx response to MAIL FROM, DATA, or ".". This is a defer
1235 that is specific to the message.
1236 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1237 a second attempt after TLS initialization fails
1239 Returns: OK - the connection was made and the delivery attempted;
1240 the result for each address is in its data block.
1241 DEFER - the connection could not be made, or something failed
1242 while setting up the SMTP session, or there was a
1243 non-message-specific error, such as a timeout.
1244 ERROR - a filter command is specified for this transport,
1245 and there was a problem setting it up; OR helo_data
1246 or add_headers or authenticated_sender is specified
1247 for this transport, and the string failed to expand
1251 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
1252 uschar *interface, transport_instance *tblock,
1253 BOOL *message_defer, BOOL suppress_tls)
1256 address_item *sync_addr;
1257 address_item *first_addr = addrlist;
1262 time_t start_delivery_time = time(NULL);
1263 smtp_transport_options_block *ob =
1264 (smtp_transport_options_block *)(tblock->options_block);
1265 BOOL lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
1266 BOOL smtps = strcmpic(ob->protocol, US"smtps") == 0;
1268 BOOL send_rset = TRUE;
1269 BOOL send_quit = TRUE;
1270 BOOL setting_up = TRUE;
1271 BOOL completed_address = FALSE;
1274 BOOL pass_message = FALSE;
1275 #ifndef DISABLE_PRDR
1276 BOOL prdr_offered = FALSE;
1279 BOOL dsn_all_lasthop = TRUE;
1280 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1283 dns_answer tlsa_dnsa;
1285 smtp_inblock inblock;
1286 smtp_outblock outblock;
1287 int max_rcpt = tblock->max_addresses;
1288 uschar *igquotstr = US"";
1289 uschar *helo_data = NULL;
1290 uschar *message = NULL;
1291 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
1293 uschar buffer[4096];
1294 uschar inbuffer[4096];
1295 uschar outbuffer[4096];
1297 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
1299 *message_defer = FALSE;
1300 smtp_command = US"initial connection";
1301 if (max_rcpt == 0) max_rcpt = 999999;
1303 /* Set up the buffer for reading SMTP response packets. */
1305 inblock.buffer = inbuffer;
1306 inblock.buffersize = sizeof(inbuffer);
1307 inblock.ptr = inbuffer;
1308 inblock.ptrend = inbuffer;
1310 /* Set up the buffer for holding SMTP commands while pipelining */
1312 outblock.buffer = outbuffer;
1313 outblock.buffersize = sizeof(outbuffer);
1314 outblock.ptr = outbuffer;
1315 outblock.cmd_count = 0;
1316 outblock.authenticating = FALSE;
1318 /* Reset the parameters of a TLS session. */
1321 tls_out.cipher = NULL; /* the one we may use for this transport */
1322 tls_out.ourcert = NULL;
1323 tls_out.peercert = NULL;
1324 tls_out.peerdn = NULL;
1325 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1328 tls_out.ocsp = OCSP_NOT_REQ;
1330 /* Flip the legacy TLS-related variables over to the outbound set in case
1331 they're used in the context of the transport. Don't bother resetting
1332 afterward as we're in a subprocess. */
1334 tls_modify_variables(&tls_out);
1339 set_errno(addrlist, ERRNO_TLSFAILURE, US"TLS support not available",
1340 DEFER, FALSE, NULL);
1345 /* Make a connection to the host if this isn't a continued delivery, and handle
1346 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
1347 specially so they can be identified for retries. */
1349 if (continue_hostname == NULL)
1351 /* This puts port into host->port */
1352 inblock.sock = outblock.sock =
1353 smtp_connect(host, host_af, port, interface, ob->connect_timeout,
1354 ob->keepalive, ob->dscp
1355 #ifdef EXPERIMENTAL_EVENT
1356 , tblock->event_action
1360 if (inblock.sock < 0)
1362 set_errno(addrlist, (errno == ETIMEDOUT)? ERRNO_CONNECTTIMEOUT : errno,
1363 NULL, DEFER, FALSE, NULL);
1367 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1369 tls_out.dane_verified = FALSE;
1370 tls_out.tlsa_usage = 0;
1372 dane_required = verify_check_given_host(&ob->hosts_require_dane, host) == OK;
1374 if (host->dnssec == DS_YES)
1377 || verify_check_given_host(&ob->hosts_try_dane, host) == OK
1379 if ((rc = tlsa_lookup(host, &tlsa_dnsa, dane_required, &dane)) != OK)
1382 else if (dane_required)
1384 log_write(0, LOG_MAIN, "DANE error: %s lookup not DNSSEC", host->name);
1389 ob->tls_tempfail_tryclear = FALSE;
1393 /* Expand the greeting message while waiting for the initial response. (Makes
1394 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1395 delayed till here so that $sending_interface and $sending_port are set. */
1397 helo_data = expand_string(ob->helo_data);
1399 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1400 is nevertheless a reasonably clean way of programming this kind of logic,
1401 where you want to escape on any error. */
1405 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1406 ob->command_timeout)) goto RESPONSE_FAILED;
1408 #ifdef EXPERIMENTAL_EVENT
1411 lookup_dnssec_authenticated = host->dnssec==DS_YES ? US"yes"
1412 : host->dnssec==DS_NO ? US"no" : NULL;
1413 s = event_raise(tblock->event_action, US"smtp:connect", buffer);
1416 set_errno(addrlist, ERRNO_EXPANDFAIL,
1417 string_sprintf("deferred by smtp:connect event expansion: %s", s),
1418 DEFER, FALSE, NULL);
1425 /* Now check if the helo_data expansion went well, and sign off cleanly if
1428 if (helo_data == NULL)
1430 uschar *message = string_sprintf("failed to expand helo_data: %s",
1431 expand_string_message);
1432 set_errno(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, NULL);
1438 /** Debugging without sending a message
1439 addrlist->transport_return = DEFER;
1443 /* Errors that occur after this point follow an SMTP command, which is
1444 left in big_buffer by smtp_write_command() for use in error messages. */
1446 smtp_command = big_buffer;
1448 /* Tell the remote who we are...
1450 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1451 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1452 greeting is of this form. The assumption was that the far end supports it
1453 properly... but experience shows that there are some that give 5xx responses,
1454 even though the banner includes "ESMTP" (there's a bloody-minded one that
1455 says "ESMTP not spoken here"). Cope with that case.
1457 September 2000: Time has passed, and it seems reasonable now to always send
1458 EHLO at the start. It is also convenient to make the change while installing
1461 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1462 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1463 would be no way to send out the mails, so there is now a host list
1464 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1465 PIPELINING problem as well. Maybe it can also be useful to cure other
1466 problems with broken servers.
1468 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1469 Then somebody tried it with a Microsoft mailer... It seems that all other
1470 mailers use upper case for some reason (the RFC is quite clear about case
1471 independence) so, for peace of mind, I gave in. */
1473 esmtp = verify_check_given_host(&ob->hosts_avoid_esmtp, host) != OK;
1475 /* Alas; be careful, since this goto is not an error-out, so conceivably
1476 we might set data between here and the target which we assume to exist
1477 and be usable. I can see this coming back to bite us. */
1482 suppress_tls = FALSE;
1483 ob->tls_tempfail_tryclear = FALSE;
1484 smtp_command = US"SSL-on-connect";
1491 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1492 lmtp? "LHLO" : "EHLO", helo_data) < 0)
1494 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1495 ob->command_timeout))
1497 if (errno != 0 || buffer[0] == 0 || lmtp) goto RESPONSE_FAILED;
1504 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1509 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1511 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1512 ob->command_timeout)) goto RESPONSE_FAILED;
1515 /* Set IGNOREQUOTA if the response to LHLO specifies support and the
1516 lmtp_ignore_quota option was set. */
1518 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1519 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1520 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1522 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1525 tls_offered = esmtp &&
1526 pcre_exec(regex_STARTTLS, NULL, CS buffer, Ustrlen(buffer), 0,
1527 PCRE_EOPT, NULL, 0) >= 0;
1530 #ifndef DISABLE_PRDR
1531 prdr_offered = esmtp
1532 && pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(buffer), 0,
1533 PCRE_EOPT, NULL, 0) >= 0
1534 && verify_check_given_host(&ob->hosts_try_prdr, host) == OK;
1537 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1541 /* For continuing deliveries down the same channel, the socket is the standard
1542 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1543 below). Set up the pointer to where subsequent commands will be left, for
1544 error messages. Note that smtp_use_size and smtp_use_pipelining will have been
1545 set from the command line if they were set in the process that passed the
1550 inblock.sock = outblock.sock = fileno(stdin);
1551 smtp_command = big_buffer;
1552 host->port = port; /* Record the port that was used */
1555 /* If TLS is available on this connection, whether continued or not, attempt to
1556 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1557 send another EHLO - the server may give a different answer in secure mode. We
1558 use a separate buffer for reading the response to STARTTLS so that if it is
1559 negative, the original EHLO data is available for subsequent analysis, should
1560 the client not be required to use TLS. If the response is bad, copy the buffer
1561 for error analysis. */
1566 && verify_check_given_host(&ob->hosts_avoid_tls, host) != OK)
1568 uschar buffer2[4096];
1569 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1572 /* If there is an I/O error, transmission of this message is deferred. If
1573 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1574 false, we also defer. However, if there is a temporary rejection of STARTTLS
1575 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1576 STARTTLS, we carry on. This means we will try to send the message in clear,
1577 unless the host is in hosts_require_tls (tested below). */
1579 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1580 ob->command_timeout))
1582 if (errno != 0 || buffer2[0] == 0 ||
1583 (buffer2[0] == '4' && !ob->tls_tempfail_tryclear))
1585 Ustrncpy(buffer, buffer2, sizeof(buffer));
1586 goto RESPONSE_FAILED;
1590 /* STARTTLS accepted: try to negotiate a TLS session. */
1595 int rc = tls_client_start(inblock.sock, host, addrlist, tblock
1596 # ifdef EXPERIMENTAL_DANE
1597 , dane ? &tlsa_dnsa : NULL
1601 /* TLS negotiation failed; give an error. From outside, this function may
1602 be called again to try in clear on a new connection, if the options permit
1603 it for this host. */
1607 # ifdef EXPERIMENTAL_DANE
1608 if (rc == DEFER && dane && !dane_required)
1610 log_write(0, LOG_MAIN, "DANE attempt failed;"
1611 " trying CA-root TLS to %s [%s] (not in hosts_require_dane)",
1612 host->name, host->address);
1618 save_errno = ERRNO_TLSFAILURE;
1619 message = US"failure while setting up TLS session";
1624 /* TLS session is set up */
1626 for (addr = addrlist; addr != NULL; addr = addr->next)
1627 if (addr->transport_return == PENDING_DEFER)
1629 addr->cipher = tls_out.cipher;
1630 addr->ourcert = tls_out.ourcert;
1631 addr->peercert = tls_out.peercert;
1632 addr->peerdn = tls_out.peerdn;
1633 addr->ocsp = tls_out.ocsp;
1638 /* if smtps, we'll have smtp_command set to something else; always safe to
1640 smtp_command = big_buffer;
1642 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1643 helo_data is null, we are dealing with a connection that was passed from
1644 another process, and so we won't have expanded helo_data above. We have to
1645 expand it here. $sending_ip_address and $sending_port are set up right at the
1646 start of the Exim process (in exim.c). */
1648 if (tls_out.active >= 0)
1651 if (helo_data == NULL)
1653 helo_data = expand_string(ob->helo_data);
1654 if (helo_data == NULL)
1656 uschar *message = string_sprintf("failed to expand helo_data: %s",
1657 expand_string_message);
1658 set_errno(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, NULL);
1664 /* For SMTPS we need to wait for the initial OK response. */
1667 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1668 ob->command_timeout)) goto RESPONSE_FAILED;
1672 greeting_cmd = "EHLO";
1675 greeting_cmd = "HELO";
1677 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1680 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1681 lmtp? "LHLO" : greeting_cmd, helo_data) < 0)
1683 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1684 ob->command_timeout))
1685 goto RESPONSE_FAILED;
1688 /* If the host is required to use a secure channel, ensure that we
1692 # ifdef EXPERIMENTAL_DANE
1695 verify_check_given_host(&ob->hosts_require_tls, host) == OK
1698 save_errno = ERRNO_TLSREQUIRED;
1699 message = string_sprintf("a TLS session is required, but %s",
1700 tls_offered? "an attempt to start TLS failed" :
1701 "the server did not offer TLS support");
1704 #endif /*SUPPORT_TLS*/
1706 /* If TLS is active, we have just started it up and re-done the EHLO command,
1707 so its response needs to be analyzed. If TLS is not active and this is a
1708 continued session down a previously-used socket, we haven't just done EHLO, so
1711 if (continue_hostname == NULL
1713 || tls_out.active >= 0
1717 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
1718 lmtp_ignore_quota option was set. */
1720 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1721 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1722 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1724 /* If the response to EHLO specified support for the SIZE parameter, note
1725 this, provided size_addition is non-negative. */
1727 smtp_use_size = esmtp && ob->size_addition >= 0 &&
1728 pcre_exec(regex_SIZE, NULL, CS buffer, Ustrlen(CS buffer), 0,
1729 PCRE_EOPT, NULL, 0) >= 0;
1731 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
1732 the current host, esmtp will be false, so PIPELINING can never be used. If
1733 the current host matches hosts_avoid_pipelining, don't do it. */
1735 smtp_use_pipelining = esmtp
1736 && verify_check_given_host(&ob->hosts_avoid_pipelining, host) != OK
1737 && pcre_exec(regex_PIPELINING, NULL, CS buffer, Ustrlen(CS buffer), 0,
1738 PCRE_EOPT, NULL, 0) >= 0;
1740 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
1741 smtp_use_pipelining? "" : "not ");
1743 #ifndef DISABLE_PRDR
1744 prdr_offered = esmtp
1745 && pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(CS buffer), 0,
1746 PCRE_EOPT, NULL, 0) >= 0
1747 && verify_check_given_host(&ob->hosts_try_prdr, host) == OK;
1750 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1753 /* Note if the server supports DSN */
1754 smtp_use_dsn = esmtp && pcre_exec(regex_DSN, NULL, CS buffer, (int)Ustrlen(CS buffer), 0,
1755 PCRE_EOPT, NULL, 0) >= 0;
1756 DEBUG(D_transport) debug_printf("use_dsn=%d\n", smtp_use_dsn);
1758 /* Note if the response to EHLO specifies support for the AUTH extension.
1759 If it has, check that this host is one we want to authenticate to, and do
1760 the business. The host name and address must be available when the
1761 authenticator's client driver is running. */
1763 switch (yield = smtp_auth(buffer, sizeof(buffer), addrlist, host,
1764 ob, esmtp, &inblock, &outblock))
1766 default: goto SEND_QUIT;
1768 case FAIL_SEND: goto SEND_FAILED;
1769 case FAIL: goto RESPONSE_FAILED;
1773 /* The setting up of the SMTP call is now complete. Any subsequent errors are
1774 message-specific. */
1778 /* If there is a filter command specified for this transport, we can now
1779 set it up. This cannot be done until the identify of the host is known. */
1781 if (tblock->filter_command != NULL)
1785 sprintf(CS buffer, "%.50s transport", tblock->name);
1786 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
1787 TRUE, DEFER, addrlist, buffer, NULL);
1788 transport_filter_timeout = tblock->filter_timeout;
1790 /* On failure, copy the error to all addresses, abandon the SMTP call, and
1795 set_errno(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
1803 /* For messages that have more than the maximum number of envelope recipients,
1804 we want to send several transactions down the same SMTP connection. (See
1805 comments in deliver.c as to how this reconciles, heuristically, with
1806 remote_max_parallel.) This optimization was added to Exim after the following
1807 code was already working. The simplest way to put it in without disturbing the
1808 code was to use a goto to jump back to this point when there is another
1809 transaction to handle. */
1812 sync_addr = first_addr;
1816 completed_address = FALSE;
1819 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
1820 qualification, send it, adding something to the message size to allow for
1821 imprecision and things that get added en route. Exim keeps the number of lines
1822 in a message, so we can give an accurate value for the original message, but we
1823 need some additional to handle added headers. (Double "." characters don't get
1824 included in the count.) */
1831 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
1835 #ifndef DISABLE_PRDR
1836 prdr_active = FALSE;
1839 for (addr = first_addr; addr; addr = addr->next)
1840 if (addr->transport_return == PENDING_DEFER)
1842 for (addr = addr->next; addr; addr = addr->next)
1843 if (addr->transport_return == PENDING_DEFER)
1844 { /* at least two recipients to send */
1846 sprintf(CS p, " PRDR"); p += 5;
1854 /* check if all addresses have lasthop flag */
1855 /* do not send RET and ENVID if true */
1856 dsn_all_lasthop = TRUE;
1857 for (addr = first_addr;
1858 address_count < max_rcpt && addr != NULL;
1860 if ((addr->dsn_flags & rf_dsnlasthop) != 1)
1861 dsn_all_lasthop = FALSE;
1863 /* Add any DSN flags to the mail command */
1865 if ((smtp_use_dsn) && (dsn_all_lasthop == FALSE))
1867 if (dsn_ret == dsn_ret_hdrs)
1869 Ustrcpy(p, " RET=HDRS");
1872 else if (dsn_ret == dsn_ret_full)
1874 Ustrcpy(p, " RET=FULL");
1877 if (dsn_envid != NULL)
1879 string_format(p, sizeof(buffer) - (p-buffer), " ENVID=%s", dsn_envid);
1884 /* If an authenticated_sender override has been specified for this transport
1885 instance, expand it. If the expansion is forced to fail, and there was already
1886 an authenticated_sender for this message, the original value will be used.
1887 Other expansion failures are serious. An empty result is ignored, but there is
1888 otherwise no check - this feature is expected to be used with LMTP and other
1889 cases where non-standard addresses (e.g. without domains) might be required. */
1891 if (smtp_mail_auth_str(p, sizeof(buffer) - (p-buffer), addrlist, ob))
1897 /* From here until we send the DATA command, we can make use of PIPELINING
1898 if the server host supports it. The code has to be able to check the responses
1899 at any point, for when the buffer fills up, so we write it totally generally.
1900 When PIPELINING is off, each command written reports that it has flushed the
1903 pending_MAIL = TRUE; /* The block starts with MAIL */
1905 rc = smtp_write_command(&outblock, smtp_use_pipelining,
1906 "MAIL FROM:<%s>%s\r\n", return_path, buffer);
1907 mail_command = string_copy(big_buffer); /* Save for later error message */
1911 case -1: /* Transmission error */
1914 case +1: /* Block was sent */
1915 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1916 ob->command_timeout))
1918 if (errno == 0 && buffer[0] == '4')
1920 errno = ERRNO_MAIL4XX;
1921 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1923 goto RESPONSE_FAILED;
1925 pending_MAIL = FALSE;
1929 /* Pass over all the relevant recipient addresses for this host, which are the
1930 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
1931 several before we have to read the responses for those seen so far. This
1932 checking is done by a subroutine because it also needs to be done at the end.
1933 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
1934 the next one if not all are sent.
1936 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
1937 last address because we want to abort if any recipients have any kind of
1938 problem, temporary or permanent. We know that all recipient addresses will have
1939 the PENDING_DEFER status, because only one attempt is ever made, and we know
1940 that max_rcpt will be large, so all addresses will be done at once. */
1942 for (addr = first_addr;
1943 address_count < max_rcpt && addr != NULL;
1949 addr->dsn_aware = smtp_use_dsn ? dsn_support_yes : dsn_support_no;
1951 if (addr->transport_return != PENDING_DEFER) continue;
1954 no_flush = smtp_use_pipelining && (!mua_wrapper || addr->next != NULL);
1956 /* Add any DSN flags to the rcpt command and add to the sent string */
1961 if (smtp_use_dsn && (addr->dsn_flags & rf_dsnlasthop) != 1)
1963 if ((addr->dsn_flags & rf_dsnflags) != 0)
1967 Ustrcpy(p, " NOTIFY=");
1969 for (i = 0; i < 4; i++)
1970 if ((addr->dsn_flags & rf_list[i]) != 0)
1972 if (!first) *p++ = ',';
1974 Ustrcpy(p, rf_names[i]);
1979 if (addr->dsn_orcpt != NULL)
1981 string_format(p, sizeof(buffer) - (p-buffer), " ORCPT=%s",
1987 /* Now send the RCPT command, and process outstanding responses when
1988 necessary. After a timeout on RCPT, we just end the function, leaving the
1989 yield as OK, because this error can often mean that there is a problem with
1990 just one address, so we don't want to delay the host. */
1992 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s%s\r\n",
1993 transport_rcpt_address(addr, tblock->rcpt_include_affixes), igquotstr, buffer);
1995 if (count < 0) goto SEND_FAILED;
1998 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
1999 &sync_addr, host, count, ob->address_retry_include_sender,
2000 pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
2003 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2004 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2007 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2008 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2009 case 0: /* No 2xx or 5xx, but no probs */
2012 case -1: goto END_OFF; /* Timeout on RCPT */
2013 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
2015 pending_MAIL = FALSE; /* Dealt with MAIL */
2017 } /* Loop for next address */
2019 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
2020 permanently or temporarily. We should have flushed and synced after the last
2025 address_item *badaddr;
2026 for (badaddr = first_addr; badaddr; badaddr = badaddr->next)
2027 if (badaddr->transport_return != PENDING_OK)
2029 /*XXX could we find a better errno than 0 here? */
2030 set_errno(addrlist, 0, badaddr->message, FAIL,
2031 testflag(badaddr, af_pass_message), NULL);
2037 /* If ok is TRUE, we know we have got at least one good recipient, and must now
2038 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
2039 have a good recipient buffered up if we are pipelining. We don't want to waste
2040 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
2041 are pipelining. The responses are all handled by sync_responses(). */
2043 if (ok || (smtp_use_pipelining && !mua_wrapper))
2045 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
2046 if (count < 0) goto SEND_FAILED;
2047 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
2048 host, count, ob->address_retry_include_sender, pending_MAIL,
2049 ok? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
2051 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2052 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2055 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2056 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2057 case 0: break; /* No 2xx or 5xx, but no probs */
2059 case -1: goto END_OFF; /* Timeout on RCPT */
2060 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2064 /* Save the first address of the next batch. */
2068 /* If there were no good recipients (but otherwise there have been no
2069 problems), just set ok TRUE, since we have handled address-specific errors
2070 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
2071 for handling the SMTP dot-handling protocol, flagging to apply to headers as
2072 well as body. Set the appropriate timeout value to be used for each chunk.
2073 (Haven't been able to make it work using select() for writing yet.) */
2075 if (!ok) ok = TRUE; else
2077 sigalrm_seen = FALSE;
2078 transport_write_timeout = ob->data_timeout;
2079 smtp_command = US"sending data block"; /* For error messages */
2080 DEBUG(D_transport|D_v)
2081 debug_printf(" SMTP>> writing message and terminating \".\"\n");
2082 transport_count = 0;
2084 #ifndef DISABLE_DKIM
2085 ok = dkim_transport_write_message(addrlist, inblock.sock,
2086 topt_use_crlf | topt_end_dot | topt_escape_headers |
2087 (tblock->body_only? topt_no_headers : 0) |
2088 (tblock->headers_only? topt_no_body : 0) |
2089 (tblock->return_path_add? topt_add_return_path : 0) |
2090 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
2091 (tblock->envelope_to_add? topt_add_envelope_to : 0),
2092 0, /* No size limit */
2093 tblock->add_headers, tblock->remove_headers,
2094 US".", US"..", /* Escaping strings */
2095 tblock->rewrite_rules, tblock->rewrite_existflags,
2096 ob->dkim_private_key, ob->dkim_domain, ob->dkim_selector,
2097 ob->dkim_canon, ob->dkim_strict, ob->dkim_sign_headers
2100 ok = transport_write_message(addrlist, inblock.sock,
2101 topt_use_crlf | topt_end_dot | topt_escape_headers |
2102 (tblock->body_only? topt_no_headers : 0) |
2103 (tblock->headers_only? topt_no_body : 0) |
2104 (tblock->return_path_add? topt_add_return_path : 0) |
2105 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
2106 (tblock->envelope_to_add? topt_add_envelope_to : 0),
2107 0, /* No size limit */
2108 tblock->add_headers, tblock->remove_headers,
2109 US".", US"..", /* Escaping strings */
2110 tblock->rewrite_rules, tblock->rewrite_existflags);
2113 /* transport_write_message() uses write() because it is called from other
2114 places to write to non-sockets. This means that under some OS (e.g. Solaris)
2115 it can exit with "Broken pipe" as its error. This really means that the
2116 socket got closed at the far end. */
2118 transport_write_timeout = 0; /* for subsequent transports */
2120 /* Failure can either be some kind of I/O disaster (including timeout),
2121 or the failure of a transport filter or the expansion of added headers. */
2125 buffer[0] = 0; /* There hasn't been a response */
2126 goto RESPONSE_FAILED;
2129 /* We used to send the terminating "." explicitly here, but because of
2130 buffering effects at both ends of TCP/IP connections, you don't gain
2131 anything by keeping it separate, so it might as well go in the final
2132 data buffer for efficiency. This is now done by setting the topt_end_dot
2135 smtp_command = US"end of data";
2137 #ifndef DISABLE_PRDR
2138 /* For PRDR we optionally get a partial-responses warning
2139 * followed by the individual responses, before going on with
2140 * the overall response. If we don't get the warning then deal
2141 * with per non-PRDR. */
2144 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '3',
2146 if (!ok && errno == 0)
2149 case '2': prdr_active = FALSE;
2152 case '4': errno = ERRNO_DATA4XX;
2153 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2160 /* For non-PRDR SMTP, we now read a single response that applies to the
2161 whole message. If it is OK, then all the addresses have been delivered. */
2165 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2167 if (!ok && errno == 0 && buffer[0] == '4')
2169 errno = ERRNO_DATA4XX;
2170 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2174 /* For LMTP, we get back a response for every RCPT command that we sent;
2175 some may be accepted and some rejected. For those that get a response, their
2176 status is fixed; any that are accepted have been handed over, even if later
2177 responses crash - at least, that's how I read RFC 2033.
2179 If all went well, mark the recipient addresses as completed, record which
2180 host/IPaddress they were delivered to, and cut out RSET when sending another
2181 message down the same channel. Write the completed addresses to the journal
2182 now so that they are recorded in case there is a crash of hardware or
2183 software before the spool gets updated. Also record the final SMTP
2184 confirmation if needed (for SMTP only). */
2189 int delivery_time = (int)(time(NULL) - start_delivery_time);
2191 uschar *conf = NULL;
2194 /* Set up confirmation if needed - applies only to SMTP */
2197 #ifndef EXPERIMENTAL_EVENT
2198 (log_extra_selector & LX_smtp_confirmation) != 0 &&
2203 uschar *s = string_printing(buffer);
2204 conf = (s == buffer)? (uschar *)string_copy(s) : s;
2207 /* Process all transported addresses - for LMTP or PRDR, read a status for
2210 for (addr = addrlist; addr != first_addr; addr = addr->next)
2212 if (addr->transport_return != PENDING_OK) continue;
2214 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
2215 remaining addresses. Otherwise, it's a return code for just the one
2216 address. For temporary errors, add a retry item for the address so that
2217 it doesn't get tried again too soon. */
2219 #ifndef DISABLE_PRDR
2220 if (lmtp || prdr_active)
2225 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2228 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
2229 addr->message = string_sprintf(
2230 #ifndef DISABLE_PRDR
2231 "%s error after %s: %s", prdr_active ? "PRDR":"LMTP",
2233 "LMTP error after %s: %s",
2235 big_buffer, string_printing(buffer));
2236 setflag(addr, af_pass_message); /* Allow message to go to user */
2237 if (buffer[0] == '5')
2238 addr->transport_return = FAIL;
2241 errno = ERRNO_DATA4XX;
2242 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2243 addr->transport_return = DEFER;
2244 #ifndef DISABLE_PRDR
2247 retry_add_item(addr, addr->address_retry_key, 0);
2251 completed_address = TRUE; /* NOW we can set this flag */
2252 if ((log_extra_selector & LX_smtp_confirmation) != 0)
2254 uschar *s = string_printing(buffer);
2255 conf = (s == buffer)? (uschar *)string_copy(s) : s;
2259 /* SMTP, or success return from LMTP for this address. Pass back the
2260 actual host that was used. */
2262 addr->transport_return = OK;
2263 addr->more_errno = delivery_time;
2264 addr->host_used = host;
2265 addr->special_action = flag;
2266 addr->message = conf;
2267 #ifndef DISABLE_PRDR
2268 if (prdr_active) addr->flags |= af_prdr_used;
2272 #ifndef DISABLE_PRDR
2276 /* Update the journal. For homonymic addresses, use the base address plus
2277 the transport name. See lots of comments in deliver.c about the reasons
2278 for the complications when homonyms are involved. Just carry on after
2279 write error, as it may prove possible to update the spool file later. */
2281 if (testflag(addr, af_homonym))
2282 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2284 sprintf(CS buffer, "%.500s\n", addr->unique);
2286 DEBUG(D_deliver) debug_printf("journalling %s", buffer);
2287 len = Ustrlen(CS buffer);
2288 if (write(journal_fd, buffer, len) != len)
2289 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2290 "%s: %s", buffer, strerror(errno));
2294 #ifndef DISABLE_PRDR
2297 /* PRDR - get the final, overall response. For any non-success
2298 upgrade all the address statuses. */
2299 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2303 if(errno == 0 && buffer[0] == '4')
2305 errno = ERRNO_DATA4XX;
2306 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2308 for (addr = addrlist; addr != first_addr; addr = addr->next)
2309 if (buffer[0] == '5' || addr->transport_return == OK)
2310 addr->transport_return = PENDING_OK; /* allow set_errno action */
2311 goto RESPONSE_FAILED;
2314 /* Update the journal, or setup retry. */
2315 for (addr = addrlist; addr != first_addr; addr = addr->next)
2316 if (addr->transport_return == OK)
2318 if (testflag(addr, af_homonym))
2319 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2321 sprintf(CS buffer, "%.500s\n", addr->unique);
2323 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s", buffer);
2324 len = Ustrlen(CS buffer);
2325 if (write(journal_fd, buffer, len) != len)
2326 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2327 "%s: %s", buffer, strerror(errno));
2329 else if (addr->transport_return == DEFER)
2330 retry_add_item(addr, addr->address_retry_key, -2);
2334 /* Ensure the journal file is pushed out to disk. */
2336 if (EXIMfsync(journal_fd) < 0)
2337 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
2343 /* Handle general (not specific to one address) failures here. The value of ok
2344 is used to skip over this code on the falling through case. A timeout causes a
2345 deferral. Other errors may defer or fail according to the response code, and
2346 may set up a special errno value, e.g. after connection chopped, which is
2347 assumed if errno == 0 and there is no text in the buffer. If control reaches
2348 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
2349 the problem is not related to this specific message. */
2358 send_quit = check_response(host, &save_errno, addrlist->more_errno,
2359 buffer, &code, &message, &pass_message);
2365 message = US string_sprintf("send() to %s [%s] failed: %s",
2366 host->name, host->address, strerror(save_errno));
2370 /* This label is jumped to directly when a TLS negotiation has failed,
2371 or was not done for a host for which it is required. Values will be set
2372 in message and save_errno, and setting_up will always be true. Treat as
2373 a temporary error. */
2380 /* If the failure happened while setting up the call, see if the failure was
2381 a 5xx response (this will either be on connection, or following HELO - a 5xx
2382 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
2383 never going to accept them. For other errors during setting up (timeouts or
2384 whatever), defer all addresses, and yield DEFER, so that the host is not
2385 tried again for a while. */
2388 ok = FALSE; /* For when reached by GOTO */
2393 set_errno(addrlist, save_errno, message, FAIL, pass_message, host);
2396 set_errno(addrlist, save_errno, message, DEFER, pass_message, host);
2401 /* We want to handle timeouts after MAIL or "." and loss of connection after
2402 "." specially. They can indicate a problem with the sender address or with
2403 the contents of the message rather than a real error on the connection. These
2404 cases are treated in the same way as a 4xx response. This next bit of code
2405 does the classification. */
2416 message_error = TRUE;
2420 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
2421 Ustrncmp(smtp_command,"end ",4) == 0;
2424 case ERRNO_SMTPCLOSED:
2425 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
2429 message_error = FALSE;
2433 /* Handle the cases that are treated as message errors. These are:
2435 (a) negative response or timeout after MAIL
2436 (b) negative response after DATA
2437 (c) negative response or timeout or dropped connection after "."
2439 It won't be a negative response or timeout after RCPT, as that is dealt
2440 with separately above. The action in all cases is to set an appropriate
2441 error code for all the addresses, but to leave yield set to OK because the
2442 host itself has not failed. Of course, it might in practice have failed
2443 when we've had a timeout, but if so, we'll discover that at the next
2444 delivery attempt. For a temporary error, set the message_defer flag, and
2445 write to the logs for information if this is not the last host. The error
2446 for the last host will be logged as part of the address's log line. */
2450 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
2451 set_errno(addrlist, save_errno, message, (code == '5')? FAIL : DEFER,
2452 pass_message, host);
2454 /* If there's an errno, the message contains just the identity of
2457 if (code != '5') /* Anything other than 5 is treated as temporary */
2460 message = US string_sprintf("%s: %s", message, strerror(save_errno));
2461 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
2462 msglog_line(host, message);
2463 *message_defer = TRUE;
2467 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
2468 ".", or some other transportation error. We defer all addresses and yield
2469 DEFER, except for the case of failed add_headers expansion, or a transport
2470 filter failure, when the yield should be ERROR, to stop it trying other
2475 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
2476 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
2477 set_errno(addrlist, save_errno, message, DEFER, pass_message, host);
2483 /* If all has gone well, send_quit will be set TRUE, implying we can end the
2484 SMTP session tidily. However, if there were too many addresses to send in one
2485 message (indicated by first_addr being non-NULL) we want to carry on with the
2486 rest of them. Also, it is desirable to send more than one message down the SMTP
2487 connection if there are several waiting, provided we haven't already sent so
2488 many as to hit the configured limit. The function transport_check_waiting looks
2489 for a waiting message and returns its id. Then transport_pass_socket tries to
2490 set up a continued delivery by passing the socket on to another process. The
2491 variable send_rset is FALSE if a message has just been successfully transfered.
2493 If we are already sending down a continued channel, there may be further
2494 addresses not yet delivered that are aimed at the same host, but which have not
2495 been passed in this run of the transport. In this case, continue_more will be
2496 true, and all we should do is send RSET if necessary, and return, leaving the
2499 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
2500 do not want to continue with other messages down the same channel, because that
2501 can lead to looping between two or more messages, all with the same,
2502 temporarily failing address(es). [The retry information isn't updated yet, so
2503 new processes keep on trying.] We probably also don't want to try more of this
2504 message's addresses either.
2506 If we have started a TLS session, we have to end it before passing the
2507 connection to a new process. However, not all servers can handle this (Exim
2508 can), so we do not pass such a connection on if the host matches
2509 hosts_nopass_tls. */
2512 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
2513 "yield=%d first_address is %sNULL\n", ok, send_quit, send_rset,
2514 continue_more, yield, (first_addr == NULL)? "":"not ");
2516 if (completed_address && ok && send_quit)
2519 if ( first_addr != NULL
2521 || ( ( tls_out.active < 0
2522 || verify_check_given_host(&ob->hosts_nopass_tls, host) != OK
2525 transport_check_waiting(tblock->name, host->name,
2526 tblock->connection_max_messages, new_message_id, &more)
2534 if (! (ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
2536 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
2537 host->address, strerror(save_errno));
2540 else if (! (ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2541 ob->command_timeout)))
2544 send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
2548 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
2549 host->name, host->address, msg);
2554 /* Either RSET was not needed, or it succeeded */
2558 if (first_addr != NULL) /* More addresses still to be sent */
2559 { /* in this run of the transport */
2560 continue_sequence++; /* Causes * in logging */
2563 if (continue_more) return yield; /* More addresses for another run */
2565 /* Pass the socket to a new Exim process. Before doing so, we must shut
2566 down TLS. Not all MTAs allow for the continuation of the SMTP session
2567 when TLS is shut down. We test for this by sending a new EHLO. If we
2568 don't get a good response, we don't attempt to pass the socket on. */
2571 if (tls_out.active >= 0)
2573 tls_close(FALSE, TRUE);
2577 ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
2578 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2579 ob->command_timeout);
2583 /* If the socket is successfully passed, we musn't send QUIT (or
2584 indeed anything!) from here. */
2586 if (ok && transport_pass_socket(tblock->name, host->name, host->address,
2587 new_message_id, inblock.sock))
2593 /* If RSET failed and there are addresses left, they get deferred. */
2595 else set_errno(first_addr, errno, msg, DEFER, FALSE, host);
2599 /* End off tidily with QUIT unless the connection has died or the socket has
2600 been passed to another process. There has been discussion on the net about what
2601 to do after sending QUIT. The wording of the RFC suggests that it is necessary
2602 to wait for a response, but on the other hand, there isn't anything one can do
2603 with an error response, other than log it. Exim used to do that. However,
2604 further discussion suggested that it is positively advantageous not to wait for
2605 the response, but to close the session immediately. This is supposed to move
2606 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
2607 load from the server. (Hosts that are both servers and clients may not see much
2608 difference, of course.) Further discussion indicated that this was safe to do
2609 on Unix systems which have decent implementations of TCP/IP that leave the
2610 connection around for a while (TIME_WAIT) after the application has gone away.
2611 This enables the response sent by the server to be properly ACKed rather than
2612 timed out, as can happen on broken TCP/IP implementations on other OS.
2614 This change is being made on 31-Jul-98. After over a year of trouble-free
2615 operation, the old commented-out code was removed on 17-Sep-99. */
2618 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2623 tls_close(FALSE, TRUE);
2626 /* Close the socket, and return the appropriate value, first setting
2627 works because the NULL setting is passed back to the calling process, and
2628 remote_max_parallel is forced to 1 when delivering over an existing connection,
2630 If all went well and continue_more is set, we shouldn't actually get here if
2631 there are further addresses, as the return above will be taken. However,
2632 writing RSET might have failed, or there may be other addresses whose hosts are
2633 specified in the transports, and therefore not visible at top level, in which
2634 case continue_more won't get set. */
2636 (void)close(inblock.sock);
2638 #ifdef EXPERIMENTAL_EVENT
2639 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
2642 continue_transport = NULL;
2643 continue_hostname = NULL;
2650 /*************************************************
2651 * Closedown entry point *
2652 *************************************************/
2654 /* This function is called when exim is passed an open smtp channel
2655 from another incarnation, but the message which it has been asked
2656 to deliver no longer exists. The channel is on stdin.
2658 We might do fancy things like looking for another message to send down
2659 the channel, but if the one we sought has gone, it has probably been
2660 delivered by some other process that itself will seek further messages,
2661 so just close down our connection.
2663 Argument: pointer to the transport instance block
2668 smtp_transport_closedown(transport_instance *tblock)
2670 smtp_transport_options_block *ob =
2671 (smtp_transport_options_block *)(tblock->options_block);
2672 smtp_inblock inblock;
2673 smtp_outblock outblock;
2675 uschar inbuffer[4096];
2676 uschar outbuffer[16];
2678 inblock.sock = fileno(stdin);
2679 inblock.buffer = inbuffer;
2680 inblock.buffersize = sizeof(inbuffer);
2681 inblock.ptr = inbuffer;
2682 inblock.ptrend = inbuffer;
2684 outblock.sock = inblock.sock;
2685 outblock.buffersize = sizeof(outbuffer);
2686 outblock.buffer = outbuffer;
2687 outblock.ptr = outbuffer;
2688 outblock.cmd_count = 0;
2689 outblock.authenticating = FALSE;
2691 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2692 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2693 ob->command_timeout);
2694 (void)close(inblock.sock);
2699 /*************************************************
2700 * Prepare addresses for delivery *
2701 *************************************************/
2703 /* This function is called to flush out error settings from previous delivery
2704 attempts to other hosts. It also records whether we got here via an MX record
2705 or not in the more_errno field of the address. We are interested only in
2706 addresses that are still marked DEFER - others may have got delivered to a
2707 previously considered IP address. Set their status to PENDING_DEFER to indicate
2708 which ones are relevant this time.
2711 addrlist the list of addresses
2712 host the host we are delivering to
2714 Returns: the first address for this delivery
2717 static address_item *
2718 prepare_addresses(address_item *addrlist, host_item *host)
2720 address_item *first_addr = NULL;
2722 for (addr = addrlist; addr != NULL; addr = addr->next)
2723 if (addr->transport_return == DEFER)
2725 if (first_addr == NULL) first_addr = addr;
2726 addr->transport_return = PENDING_DEFER;
2727 addr->basic_errno = 0;
2728 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
2729 addr->message = NULL;
2731 addr->cipher = NULL;
2732 addr->ourcert = NULL;
2733 addr->peercert = NULL;
2734 addr->peerdn = NULL;
2735 addr->ocsp = OCSP_NOT_REQ;
2743 /*************************************************
2744 * Main entry point *
2745 *************************************************/
2747 /* See local README for interface details. As this is a remote transport, it is
2748 given a chain of addresses to be delivered in one connection, if possible. It
2749 always returns TRUE, indicating that each address has its own independent
2750 status set, except if there is a setting up problem, in which case it returns
2754 smtp_transport_entry(
2755 transport_instance *tblock, /* data for this instantiation */
2756 address_item *addrlist) /* addresses we are working on */
2760 int hosts_defer = 0;
2762 int hosts_looked_up = 0;
2763 int hosts_retry = 0;
2764 int hosts_serial = 0;
2765 int hosts_total = 0;
2766 int total_hosts_tried = 0;
2768 BOOL expired = TRUE;
2769 BOOL continuing = continue_hostname != NULL;
2770 uschar *expanded_hosts = NULL;
2772 uschar *tid = string_sprintf("%s transport", tblock->name);
2773 smtp_transport_options_block *ob =
2774 (smtp_transport_options_block *)(tblock->options_block);
2775 host_item *hostlist = addrlist->host_list;
2776 host_item *host = NULL;
2780 debug_printf("%s transport entered\n", tblock->name);
2781 for (addr = addrlist; addr != NULL; addr = addr->next)
2782 debug_printf(" %s\n", addr->address);
2783 if (continuing) debug_printf("already connected to %s [%s]\n",
2784 continue_hostname, continue_host_address);
2787 /* Set the flag requesting that these hosts be added to the waiting
2788 database if the delivery fails temporarily or if we are running with
2789 queue_smtp or a 2-stage queue run. This gets unset for certain
2790 kinds of error, typically those that are specific to the message. */
2792 update_waiting = TRUE;
2794 /* If a host list is not defined for the addresses - they must all have the
2795 same one in order to be passed to a single transport - or if the transport has
2796 a host list with hosts_override set, use the host list supplied with the
2797 transport. It is an error for this not to exist. */
2799 if (hostlist == NULL || (ob->hosts_override && ob->hosts != NULL))
2801 if (ob->hosts == NULL)
2803 addrlist->message = string_sprintf("%s transport called with no hosts set",
2805 addrlist->transport_return = PANIC;
2806 return FALSE; /* Only top address has status */
2809 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
2812 /* If the transport's host list contains no '$' characters, and we are not
2813 randomizing, it is fixed and therefore a chain of hosts can be built once
2814 and for all, and remembered for subsequent use by other calls to this
2815 transport. If, on the other hand, the host list does contain '$', or we are
2816 randomizing its order, we have to rebuild it each time. In the fixed case,
2817 as the hosts string will never be used again, it doesn't matter that we
2818 replace all the : characters with zeros. */
2820 if (ob->hostlist == NULL)
2822 uschar *s = ob->hosts;
2824 if (Ustrchr(s, '$') != NULL)
2826 if (!(expanded_hosts = expand_string(s)))
2828 addrlist->message = string_sprintf("failed to expand list of hosts "
2829 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
2830 addrlist->transport_return = search_find_defer? DEFER : PANIC;
2831 return FALSE; /* Only top address has status */
2833 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
2834 "\"%s\"\n", s, expanded_hosts);
2838 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
2840 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
2842 /* Check that the expansion yielded something useful. */
2843 if (hostlist == NULL)
2846 string_sprintf("%s transport has empty hosts setting", tblock->name);
2847 addrlist->transport_return = PANIC;
2848 return FALSE; /* Only top address has status */
2851 /* If there was no expansion of hosts, save the host list for
2854 if (!expanded_hosts) ob->hostlist = hostlist;
2857 /* This is not the first time this transport has been run in this delivery;
2858 the host list was built previously. */
2860 else hostlist = ob->hostlist;
2863 /* The host list was supplied with the address. If hosts_randomize is set, we
2864 must sort it into a random order if it did not come from MX records and has not
2865 already been randomized (but don't bother if continuing down an existing
2868 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continuing)
2870 host_item *newlist = NULL;
2871 while (hostlist != NULL)
2873 host_item *h = hostlist;
2874 hostlist = hostlist->next;
2876 h->sort_key = random_number(100);
2878 if (newlist == NULL)
2883 else if (h->sort_key < newlist->sort_key)
2890 host_item *hh = newlist;
2891 while (hh->next != NULL)
2893 if (h->sort_key < hh->next->sort_key) break;
2901 hostlist = addrlist->host_list = newlist;
2905 /* Sort out the default port. */
2907 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
2910 /* For each host-plus-IP-address on the list:
2912 . If this is a continued delivery and the host isn't the one with the
2913 current connection, skip.
2915 . If the status is unusable (i.e. previously failed or retry checked), skip.
2917 . If no IP address set, get the address, either by turning the name into
2918 an address, calling gethostbyname if gethostbyname is on, or by calling
2919 the DNS. The DNS may yield multiple addresses, in which case insert the
2920 extra ones into the list.
2922 . Get the retry data if not previously obtained for this address and set the
2923 field which remembers the state of this address. Skip if the retry time is
2924 not reached. If not, remember whether retry data was found. The retry string
2925 contains both the name and the IP address.
2927 . Scan the list of addresses and mark those whose status is DEFER as
2928 PENDING_DEFER. These are the only ones that will be processed in this cycle
2931 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
2932 Some addresses may be successfully delivered, others may fail, and yet
2933 others may get temporary errors and so get marked DEFER.
2935 . The return from the delivery attempt is OK if a connection was made and a
2936 valid SMTP dialogue was completed. Otherwise it is DEFER.
2938 . If OK, add a "remove" retry item for this host/IPaddress, if any.
2940 . If fail to connect, or other defer state, add a retry item.
2942 . If there are any addresses whose status is still DEFER, carry on to the
2943 next host/IPaddress, unless we have tried the number of hosts given
2944 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
2945 there is some fancy logic for hosts_max_try that means its limit can be
2946 overstepped in some circumstances.
2948 If we get to the end of the list, all hosts have deferred at least one address,
2949 or not reached their retry times. If delay_after_cutoff is unset, it requests a
2950 delivery attempt to those hosts whose last try was before the arrival time of
2951 the current message. To cope with this, we have to go round the loop a second
2952 time. After that, set the status and error data for any addresses that haven't
2953 had it set already. */
2955 for (cutoff_retry = 0; expired &&
2956 cutoff_retry < ((ob->delay_after_cutoff)? 1 : 2);
2959 host_item *nexthost = NULL;
2960 int unexpired_hosts_tried = 0;
2962 for (host = hostlist;
2964 unexpired_hosts_tried < ob->hosts_max_try &&
2965 total_hosts_tried < ob->hosts_max_try_hardlimit;
2971 BOOL serialized = FALSE;
2972 BOOL host_is_expired = FALSE;
2973 BOOL message_defer = FALSE;
2974 BOOL ifchanges = FALSE;
2975 BOOL some_deferred = FALSE;
2976 address_item *first_addr = NULL;
2977 uschar *interface = NULL;
2978 uschar *retry_host_key = NULL;
2979 uschar *retry_message_key = NULL;
2980 uschar *serialize_key = NULL;
2982 /* Default next host is next host. :-) But this can vary if the
2983 hosts_max_try limit is hit (see below). It may also be reset if a host
2984 address is looked up here (in case the host was multihomed). */
2986 nexthost = host->next;
2988 /* If the address hasn't yet been obtained from the host name, look it up
2989 now, unless the host is already marked as unusable. If it is marked as
2990 unusable, it means that the router was unable to find its IP address (in
2991 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
2992 the lookup failed last time. We don't get this far if *all* MX records
2993 point to non-existent hosts; that is treated as a hard error.
2995 We can just skip this host entirely. When the hosts came from the router,
2996 the address will timeout based on the other host(s); when the address is
2997 looked up below, there is an explicit retry record added.
2999 Note that we mustn't skip unusable hosts if the address is not unset; they
3000 may be needed as expired hosts on the 2nd time round the cutoff loop. */
3002 if (host->address == NULL)
3004 int new_port, flags;
3006 uschar *canonical_name;
3008 if (host->status >= hstatus_unusable)
3010 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
3015 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
3017 /* The host name is permitted to have an attached port. Find it, and
3018 strip it from the name. Just remember it for now. */
3020 new_port = host_item_get_port(host);
3022 /* Count hosts looked up */
3026 /* Find by name if so configured, or if it's an IP address. We don't
3027 just copy the IP address, because we need the test-for-local to happen. */
3029 flags = HOST_FIND_BY_A;
3030 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
3031 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
3033 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
3034 rc = host_find_byname(host, NULL, flags, &canonical_name, TRUE);
3036 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
3037 ob->dnssec_request_domains, ob->dnssec_require_domains,
3038 &canonical_name, NULL);
3040 /* Update the host (and any additional blocks, resulting from
3041 multihoming) with a host-specific port, if any. */
3043 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
3045 /* Failure to find the host at this time (usually DNS temporary failure)
3046 is really a kind of routing failure rather than a transport failure.
3047 Therefore we add a retry item of the routing kind, not to stop us trying
3048 to look this name up here again, but to ensure the address gets timed
3049 out if the failures go on long enough. A complete failure at this point
3050 commonly points to a configuration error, but the best action is still
3051 to carry on for the next host. */
3053 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
3055 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
3057 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
3058 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
3059 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
3060 host->status = hstatus_unusable;
3062 for (addr = addrlist; addr != NULL; addr = addr->next)
3064 if (addr->transport_return != DEFER) continue;
3065 addr->basic_errno = ERRNO_UNKNOWNHOST;
3067 string_sprintf("failed to lookup IP address for %s", host->name);
3072 /* If the host is actually the local host, we may have a problem, or
3073 there may be some cunning configuration going on. In the problem case,
3074 log things and give up. The default transport status is already DEFER. */
3076 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
3078 for (addr = addrlist; addr != NULL; addr = addr->next)
3080 addr->basic_errno = 0;
3081 addr->message = string_sprintf("%s transport found host %s to be "
3082 "local", tblock->name, host->name);
3086 } /* End of block for IP address lookup */
3088 /* If this is a continued delivery, we are interested only in the host
3089 which matches the name of the existing open channel. The check is put
3090 here after the local host lookup, in case the name gets expanded as a
3091 result of the lookup. Set expired FALSE, to save the outer loop executing
3094 if (continuing && (Ustrcmp(continue_hostname, host->name) != 0 ||
3095 Ustrcmp(continue_host_address, host->address) != 0))
3098 continue; /* With next host */
3101 /* Reset the default next host in case a multihomed host whose addresses
3102 are not looked up till just above added to the host list. */
3104 nexthost = host->next;
3106 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
3107 domain is in queue_smtp_domains, we don't actually want to attempt any
3108 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
3109 there is a lookup defer in queue_smtp_domains, proceed as if the domain
3110 were not in it. We don't want to hold up all SMTP deliveries! Except when
3111 doing a two-stage queue run, don't do this if forcing. */
3113 if ((!deliver_force || queue_2stage) && (queue_smtp ||
3114 match_isinlist(addrlist->domain, &queue_smtp_domains, 0,
3115 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
3118 for (addr = addrlist; addr != NULL; addr = addr->next)
3120 if (addr->transport_return != DEFER) continue;
3121 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
3123 continue; /* With next host */
3126 /* Count hosts being considered - purely for an intelligent comment
3127 if none are usable. */
3131 /* Set $host and $host address now in case they are needed for the
3132 interface expansion or the serialize_hosts check; they remain set if an
3133 actual delivery happens. */
3135 deliver_host = host->name;
3136 deliver_host_address = host->address;
3137 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
3138 : host->dnssec == DS_NO ? US"no"
3141 /* Set up a string for adding to the retry key if the port number is not
3142 the standard SMTP port. A host may have its own port setting that overrides
3145 pistring = string_sprintf(":%d", (host->port == PORT_NONE)?
3147 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
3149 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
3150 string changes upon expansion, we must add it to the key that is used for
3151 retries, because connections to the same host from a different interface
3152 should be treated separately. */
3154 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET : AF_INET6;
3155 if (!smtp_get_interface(ob->interface, host_af, addrlist, &ifchanges,
3158 if (ifchanges) pistring = string_sprintf("%s/%s", pistring, interface);
3160 /* The first time round the outer loop, check the status of the host by
3161 inspecting the retry data. The second time round, we are interested only
3162 in expired hosts that haven't been tried since this message arrived. */
3164 if (cutoff_retry == 0)
3167 /* Ensure the status of the address is set by checking retry data if
3168 necessary. There may be host-specific retry data (applicable to all
3169 messages) and also data for retries of a specific message at this host.
3170 If either of these retry records are actually read, the keys used are
3171 returned to save recomputing them later. */
3173 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3174 US"retry_include_ip_address", ob->retry_include_ip_address,
3175 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3176 continue; /* with next host */
3178 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
3179 incl_ip, &retry_host_key, &retry_message_key);
3181 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
3182 (host->address == NULL)? US"" : host->address, pistring,
3183 (host->status == hstatus_usable)? "usable" :
3184 (host->status == hstatus_unusable)? "unusable" :
3185 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
3187 /* Skip this address if not usable at this time, noting if it wasn't
3188 actually expired, both locally and in the address. */
3190 switch (host->status)
3192 case hstatus_unusable:
3194 setflag(addrlist, af_retry_skipped);
3197 case hstatus_unusable_expired:
3200 case hwhy_retry: hosts_retry++; break;
3201 case hwhy_failed: hosts_fail++; break;
3202 case hwhy_deferred: hosts_defer++; break;
3205 /* If there was a retry message key, implying that previously there
3206 was a message-specific defer, we don't want to update the list of
3207 messages waiting for these hosts. */
3209 if (retry_message_key != NULL) update_waiting = FALSE;
3210 continue; /* With the next host or IP address */
3214 /* Second time round the loop: if the address is set but expired, and
3215 the message is newer than the last try, let it through. */
3219 if (host->address == NULL ||
3220 host->status != hstatus_unusable_expired ||
3221 host->last_try > received_time)
3224 debug_printf("trying expired host %s [%s]%s\n",
3225 host->name, host->address, pistring);
3226 host_is_expired = TRUE;
3229 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
3230 it remains TRUE only if all hosts are expired and none are actually tried.
3235 /* If this host is listed as one to which access must be serialized,
3236 see if another Exim process has a connection to it, and if so, skip
3237 this host. If not, update the database to record our connection to it
3238 and remember this for later deletion. Do not do any of this if we are
3239 sending the message down a pre-existing connection. */
3242 verify_check_given_host(&ob->serialize_hosts, host) == OK)
3244 serialize_key = string_sprintf("host-serialize-%s", host->name);
3245 if (!enq_start(serialize_key))
3248 debug_printf("skipping host %s because another Exim process "
3249 "is connected to it\n", host->name);
3256 /* OK, we have an IP address that is not waiting for its retry time to
3257 arrive (it might be expired) OR (second time round the loop) we have an
3258 expired host that hasn't been tried since the message arrived. Have a go
3259 at delivering the message to it. First prepare the addresses by flushing
3260 out the result of previous attempts, and finding the first address that
3261 is still to be delivered. */
3263 first_addr = prepare_addresses(addrlist, host);
3265 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
3266 message_id, host->name, host->address, addrlist->address,
3267 (addrlist->next == NULL)? "" : ", ...");
3269 set_process_info("delivering %s to %s [%s] (%s%s)",
3270 message_id, host->name, host->address, addrlist->address,
3271 (addrlist->next == NULL)? "" : ", ...");
3273 /* This is not for real; don't do the delivery. If there are
3274 any remaining hosts, list them. */
3279 set_errno(addrlist, 0, NULL, OK, FALSE, NULL);
3280 for (addr = addrlist; addr != NULL; addr = addr->next)
3282 addr->host_used = host;
3283 addr->special_action = '*';
3284 addr->message = US"delivery bypassed by -N option";
3288 debug_printf("*** delivery by %s transport bypassed by -N option\n"
3289 "*** host and remaining hosts:\n", tblock->name);
3290 for (host2 = host; host2 != NULL; host2 = host2->next)
3291 debug_printf(" %s [%s]\n", host2->name,
3292 (host2->address == NULL)? US"unset" : host2->address);
3297 /* This is for real. If the host is expired, we don't count it for
3298 hosts_max_retry. This ensures that all hosts must expire before an address
3299 is timed out, unless hosts_max_try_hardlimit (which protects against
3300 lunatic DNS configurations) is reached.
3302 If the host is not expired and we are about to hit the hosts_max_retry
3303 limit, check to see if there is a subsequent hosts with a different MX
3304 value. If so, make that the next host, and don't count this one. This is a
3305 heuristic to make sure that different MXs do get tried. With a normal kind
3306 of retry rule, they would get tried anyway when the earlier hosts were
3307 delayed, but if the domain has a "retry every time" type of rule - as is
3308 often used for the the very large ISPs, that won't happen. */
3313 /* Make a copy of the host if it is local to this invocation
3314 of the transport. */
3318 thost = store_get(sizeof(host_item));
3320 thost->name = string_copy(host->name);
3321 thost->address = string_copy(host->address);
3326 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
3330 debug_printf("hosts_max_try limit reached with this host\n");
3331 for (h = host; h != NULL; h = h->next)
3332 if (h->mx != host->mx) break;
3336 unexpired_hosts_tried--;
3337 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
3338 "and will be tried\n");
3342 /* Attempt the delivery. */
3344 total_hosts_tried++;
3345 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
3346 &message_defer, FALSE);
3349 OK => connection made, each address contains its result;
3350 message_defer is set for message-specific defers (when all
3351 recipients are marked defer)
3352 DEFER => there was a non-message-specific delivery problem;
3353 ERROR => there was a problem setting up the arguments for a filter,
3354 or there was a problem with expanding added headers
3357 /* If the result is not OK, there was a non-message-specific problem.
3358 If the result is DEFER, we need to write to the logs saying what happened
3359 for this particular host, except in the case of authentication and TLS
3360 failures, where the log has already been written. If all hosts defer a
3361 general message is written at the end. */
3363 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL &&
3364 first_addr->basic_errno != ERRNO_TLSFAILURE)
3365 write_logs(first_addr, host);
3367 #ifdef EXPERIMENTAL_EVENT
3369 deferred_event_raise(first_addr, host);
3372 /* If STARTTLS was accepted, but there was a failure in setting up the
3373 TLS session (usually a certificate screwup), and the host is not in
3374 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
3375 TLS forcibly turned off. We have to start from scratch with a new SMTP
3376 connection. That's why the retry is done from here, not from within
3377 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
3378 session, so the in-clear transmission after those errors, if permitted,
3379 happens inside smtp_deliver().] */
3383 && first_addr->basic_errno == ERRNO_TLSFAILURE
3384 && ob->tls_tempfail_tryclear
3385 && verify_check_given_host(&ob->hosts_require_tls, host) != OK
3388 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
3389 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
3390 first_addr = prepare_addresses(addrlist, host);
3391 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
3392 &message_defer, TRUE);
3393 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
3394 write_logs(first_addr, host);
3395 # ifdef EXPERIMENTAL_EVENT
3397 deferred_event_raise(first_addr, host);
3400 #endif /*SUPPORT_TLS*/
3403 /* Delivery attempt finished */
3405 rs = (rc == OK)? US"OK" : (rc == DEFER)? US"DEFER" : (rc == ERROR)?
3408 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
3409 message_id, host->name, host->address, addrlist->address,
3410 (addrlist->next == NULL)? "" : " (& others)", rs);
3412 /* Release serialization if set up */
3414 if (serialized) enq_end(serialize_key);
3416 /* If the result is DEFER, or if a host retry record is known to exist, we
3417 need to add an item to the retry chain for updating the retry database
3418 at the end of delivery. We only need to add the item to the top address,
3419 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
3420 for any other delivery attempts using the same address. (It is copied into
3421 the unusable tree at the outer level, so even if different address blocks
3422 contain the same address, it still won't get tried again.) */
3424 if (rc == DEFER || retry_host_key != NULL)
3426 int delete_flag = (rc != DEFER)? rf_delete : 0;
3427 if (retry_host_key == NULL)
3430 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3431 US"retry_include_ip_address", ob->retry_include_ip_address,
3432 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3433 incl_ip = TRUE; /* error; use most-specific retry record */
3435 retry_host_key = incl_ip ?
3436 string_sprintf("T:%S:%s%s", host->name, host->address, pistring) :
3437 string_sprintf("T:%S%s", host->name, pistring);
3440 /* If a delivery of another message over an existing SMTP connection
3441 yields DEFER, we do NOT set up retry data for the host. This covers the
3442 case when there are delays in routing the addresses in the second message
3443 that are so long that the server times out. This is alleviated by not
3444 routing addresses that previously had routing defers when handling an
3445 existing connection, but even so, this case may occur (e.g. if a
3446 previously happily routed address starts giving routing defers). If the
3447 host is genuinely down, another non-continued message delivery will
3448 notice it soon enough. */
3450 if (delete_flag != 0 || !continuing)
3451 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
3453 /* We may have tried an expired host, if its retry time has come; ensure
3454 the status reflects the expiry for the benefit of any other addresses. */
3458 host->status = (host_is_expired)?
3459 hstatus_unusable_expired : hstatus_unusable;
3460 host->why = hwhy_deferred;
3464 /* If message_defer is set (host was OK, but every recipient got deferred
3465 because of some message-specific problem), or if that had happened
3466 previously so that a message retry key exists, add an appropriate item
3467 to the retry chain. Note that if there was a message defer but now there is
3468 a host defer, the message defer record gets deleted. That seems perfectly
3469 reasonable. Also, stop the message from being remembered as waiting
3470 for specific hosts. */
3472 if (message_defer || retry_message_key != NULL)
3474 int delete_flag = message_defer? 0 : rf_delete;
3475 if (retry_message_key == NULL)
3478 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3479 US"retry_include_ip_address", ob->retry_include_ip_address,
3480 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3481 incl_ip = TRUE; /* error; use most-specific retry record */
3483 retry_message_key = incl_ip ?
3484 string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
3486 string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
3488 retry_add_item(addrlist, retry_message_key,
3489 rf_message | rf_host | delete_flag);
3490 update_waiting = FALSE;
3493 /* Any return other than DEFER (that is, OK or ERROR) means that the
3494 addresses have got their final statuses filled in for this host. In the OK
3495 case, see if any of them are deferred. */
3499 for (addr = addrlist; addr != NULL; addr = addr->next)
3501 if (addr->transport_return == DEFER)
3503 some_deferred = TRUE;
3509 /* If no addresses deferred or the result was ERROR, return. We do this for
3510 ERROR because a failing filter set-up or add_headers expansion is likely to
3511 fail for any host we try. */
3513 if (rc == ERROR || (rc == OK && !some_deferred))
3515 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3516 return TRUE; /* Each address has its status */
3519 /* If the result was DEFER or some individual addresses deferred, let
3520 the loop run to try other hosts with the deferred addresses, except for the
3521 case when we were trying to deliver down an existing channel and failed.
3522 Don't try any other hosts in this case. */
3524 if (continuing) break;
3526 /* If the whole delivery, or some individual addresses, were deferred and
3527 there are more hosts that could be tried, do not count this host towards
3528 the hosts_max_try limit if the age of the message is greater than the
3529 maximum retry time for this host. This means we may try try all hosts,
3530 ignoring the limit, when messages have been around for some time. This is
3531 important because if we don't try all hosts, the address will never time
3532 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
3534 if ((rc == DEFER || some_deferred) && nexthost != NULL)
3537 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
3539 if (retry != NULL && retry->rules != NULL)
3541 retry_rule *last_rule;
3542 for (last_rule = retry->rules;
3543 last_rule->next != NULL;
3544 last_rule = last_rule->next);
3545 timedout = time(NULL) - received_time > last_rule->timeout;
3547 else timedout = TRUE; /* No rule => timed out */
3551 unexpired_hosts_tried--;
3552 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
3553 "hosts_max_try (message older than host's retry time)\n");
3556 } /* End of loop for trying multiple hosts. */
3558 /* This is the end of the loop that repeats iff expired is TRUE and
3559 ob->delay_after_cutoff is FALSE. The second time round we will
3560 try those hosts that haven't been tried since the message arrived. */
3564 debug_printf("all IP addresses skipped or deferred at least one address\n");
3565 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
3566 debug_printf("retrying IP addresses not tried since message arrived\n");
3571 /* Get here if all IP addresses are skipped or defer at least one address. In
3572 MUA wrapper mode, this will happen only for connection or other non-message-
3573 specific failures. Force the delivery status for all addresses to FAIL. */
3577 for (addr = addrlist; addr != NULL; addr = addr->next)
3578 addr->transport_return = FAIL;
3582 /* In the normal, non-wrapper case, add a standard message to each deferred
3583 address if there hasn't been an error, that is, if it hasn't actually been
3584 tried this time. The variable "expired" will be FALSE if any deliveries were
3585 actually tried, or if there was at least one host that was not expired. That
3586 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
3587 a delivery has been tried, an error code will be set, and the failing of the
3588 message is handled by the retry code later.
3590 If queue_smtp is set, or this transport was called to send a subsequent message
3591 down an existing TCP/IP connection, and something caused the host not to be
3592 found, we end up here, but can detect these cases and handle them specially. */
3594 for (addr = addrlist; addr != NULL; addr = addr->next)
3596 /* If host is not NULL, it means that we stopped processing the host list
3597 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
3598 means we need to behave as if some hosts were skipped because their retry
3599 time had not come. Specifically, this prevents the address from timing out.
3600 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
3601 hosts were tried. */
3605 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
3608 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
3609 "hosts were tried\n");
3614 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
3615 setflag(addr, af_retry_skipped);
3619 if (queue_smtp) /* no deliveries attempted */
3621 addr->transport_return = DEFER;
3622 addr->basic_errno = 0;
3623 addr->message = US"SMTP delivery explicitly queued";
3626 else if (addr->transport_return == DEFER &&
3627 (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0) &&
3628 addr->message == NULL)
3630 addr->basic_errno = ERRNO_HRETRY;
3631 if (continue_hostname != NULL)
3633 addr->message = US"no host found for existing SMTP connection";
3637 setflag(addr, af_pass_message); /* This is not a security risk */
3638 addr->message = (ob->delay_after_cutoff)?
3639 US"retry time not reached for any host after a long failure period" :
3640 US"all hosts have been failing for a long time and were last tried "
3641 "after this message arrived";
3643 /* If we are already using fallback hosts, or there are no fallback hosts
3644 defined, convert the result to FAIL to cause a bounce. */
3646 if (addr->host_list == addr->fallback_hosts ||
3647 addr->fallback_hosts == NULL)
3648 addr->transport_return = FAIL;
3652 if (hosts_retry == hosts_total)
3653 addr->message = US"retry time not reached for any host";
3654 else if (hosts_fail == hosts_total)
3655 addr->message = US"all host address lookups failed permanently";
3656 else if (hosts_defer == hosts_total)
3657 addr->message = US"all host address lookups failed temporarily";
3658 else if (hosts_serial == hosts_total)
3659 addr->message = US"connection limit reached for all hosts";
3660 else if (hosts_fail+hosts_defer == hosts_total)
3661 addr->message = US"all host address lookups failed";
3662 else addr->message = US"some host address lookups failed and retry time "
3663 "not reached for other hosts or connection limit reached";
3668 /* Update the database which keeps information about which messages are waiting
3669 for which hosts to become available. For some message-specific errors, the
3670 update_waiting flag is turned off because we don't want follow-on deliveries in
3671 those cases. If this transport instance is explicitly limited to one message
3672 per connection then follow-on deliveries are not possible and there's no need
3673 to create/update the per-transport wait-<transport_name> database. */
3675 if (update_waiting && tblock->connection_max_messages != 1)
3676 transport_update_waiting(hostlist, tblock->name);
3680 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3682 return TRUE; /* Each address has its status */
3687 /* End of transport/smtp.c */