1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2016 */
6 /* See the file NOTICE for conditions of use and distribution. */
12 #define PENDING_DEFER (PENDING + DEFER)
13 #define PENDING_OK (PENDING + OK)
15 #define DELIVER_BUFFER_SIZE 4096
18 /* Options specific to the smtp transport. This transport also supports LMTP
19 over TCP/IP. The options must be in alphabetic order (note that "_" comes
20 before the lower case letters). Some live in the transport_instance block so as
21 to be publicly visible; these are flagged with opt_public. */
23 optionlist smtp_transport_options[] = {
24 { "*expand_multi_domain", opt_stringptr | opt_hidden | opt_public,
25 (void *)offsetof(transport_instance, expand_multi_domain) },
26 { "*expand_retry_include_ip_address", opt_stringptr | opt_hidden,
27 (void *)(offsetof(smtp_transport_options_block, expand_retry_include_ip_address)) },
29 { "address_retry_include_sender", opt_bool,
30 (void *)offsetof(smtp_transport_options_block, address_retry_include_sender) },
31 { "allow_localhost", opt_bool,
32 (void *)offsetof(smtp_transport_options_block, allow_localhost) },
33 { "authenticated_sender", opt_stringptr,
34 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
35 { "authenticated_sender_force", opt_bool,
36 (void *)offsetof(smtp_transport_options_block, authenticated_sender_force) },
37 { "command_timeout", opt_time,
38 (void *)offsetof(smtp_transport_options_block, command_timeout) },
39 { "connect_timeout", opt_time,
40 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
41 { "connection_max_messages", opt_int | opt_public,
42 (void *)offsetof(transport_instance, connection_max_messages) },
43 { "data_timeout", opt_time,
44 (void *)offsetof(smtp_transport_options_block, data_timeout) },
45 { "delay_after_cutoff", opt_bool,
46 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
48 { "dkim_canon", opt_stringptr,
49 (void *)offsetof(smtp_transport_options_block, dkim.dkim_canon) },
50 { "dkim_domain", opt_stringptr,
51 (void *)offsetof(smtp_transport_options_block, dkim.dkim_domain) },
52 { "dkim_private_key", opt_stringptr,
53 (void *)offsetof(smtp_transport_options_block, dkim.dkim_private_key) },
54 { "dkim_selector", opt_stringptr,
55 (void *)offsetof(smtp_transport_options_block, dkim.dkim_selector) },
56 { "dkim_sign_headers", opt_stringptr,
57 (void *)offsetof(smtp_transport_options_block, dkim.dkim_sign_headers) },
58 { "dkim_strict", opt_stringptr,
59 (void *)offsetof(smtp_transport_options_block, dkim.dkim_strict) },
61 { "dns_qualify_single", opt_bool,
62 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
63 { "dns_search_parents", opt_bool,
64 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
65 { "dnssec_request_domains", opt_stringptr,
66 (void *)offsetof(smtp_transport_options_block, dnssec.request) },
67 { "dnssec_require_domains", opt_stringptr,
68 (void *)offsetof(smtp_transport_options_block, dnssec.require) },
69 { "dscp", opt_stringptr,
70 (void *)offsetof(smtp_transport_options_block, dscp) },
71 { "fallback_hosts", opt_stringptr,
72 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
73 { "final_timeout", opt_time,
74 (void *)offsetof(smtp_transport_options_block, final_timeout) },
75 { "gethostbyname", opt_bool,
76 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
77 { "helo_data", opt_stringptr,
78 (void *)offsetof(smtp_transport_options_block, helo_data) },
79 { "hosts", opt_stringptr,
80 (void *)offsetof(smtp_transport_options_block, hosts) },
81 { "hosts_avoid_esmtp", opt_stringptr,
82 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
83 { "hosts_avoid_pipelining", opt_stringptr,
84 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
86 { "hosts_avoid_tls", opt_stringptr,
87 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
89 { "hosts_max_try", opt_int,
90 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
91 { "hosts_max_try_hardlimit", opt_int,
92 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
94 { "hosts_nopass_tls", opt_stringptr,
95 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
97 { "hosts_override", opt_bool,
98 (void *)offsetof(smtp_transport_options_block, hosts_override) },
99 { "hosts_randomize", opt_bool,
100 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
101 #if defined(SUPPORT_TLS) && !defined(DISABLE_OCSP)
102 { "hosts_request_ocsp", opt_stringptr,
103 (void *)offsetof(smtp_transport_options_block, hosts_request_ocsp) },
105 { "hosts_require_auth", opt_stringptr,
106 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
108 # ifdef EXPERIMENTAL_DANE
109 { "hosts_require_dane", opt_stringptr,
110 (void *)offsetof(smtp_transport_options_block, hosts_require_dane) },
112 # ifndef DISABLE_OCSP
113 { "hosts_require_ocsp", opt_stringptr,
114 (void *)offsetof(smtp_transport_options_block, hosts_require_ocsp) },
116 { "hosts_require_tls", opt_stringptr,
117 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
119 { "hosts_try_auth", opt_stringptr,
120 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
121 { "hosts_try_chunking", opt_stringptr,
122 (void *)offsetof(smtp_transport_options_block, hosts_try_chunking) },
123 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
124 { "hosts_try_dane", opt_stringptr,
125 (void *)offsetof(smtp_transport_options_block, hosts_try_dane) },
127 { "hosts_try_fastopen", opt_stringptr,
128 (void *)offsetof(smtp_transport_options_block, hosts_try_fastopen) },
130 { "hosts_try_prdr", opt_stringptr,
131 (void *)offsetof(smtp_transport_options_block, hosts_try_prdr) },
134 { "hosts_verify_avoid_tls", opt_stringptr,
135 (void *)offsetof(smtp_transport_options_block, hosts_verify_avoid_tls) },
137 { "interface", opt_stringptr,
138 (void *)offsetof(smtp_transport_options_block, interface) },
139 { "keepalive", opt_bool,
140 (void *)offsetof(smtp_transport_options_block, keepalive) },
141 { "lmtp_ignore_quota", opt_bool,
142 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
143 { "max_rcpt", opt_int | opt_public,
144 (void *)offsetof(transport_instance, max_addresses) },
145 { "multi_domain", opt_expand_bool | opt_public,
146 (void *)offsetof(transport_instance, multi_domain) },
147 { "port", opt_stringptr,
148 (void *)offsetof(smtp_transport_options_block, port) },
149 { "protocol", opt_stringptr,
150 (void *)offsetof(smtp_transport_options_block, protocol) },
151 { "retry_include_ip_address", opt_expand_bool,
152 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
153 { "serialize_hosts", opt_stringptr,
154 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
155 { "size_addition", opt_int,
156 (void *)offsetof(smtp_transport_options_block, size_addition) }
158 ,{ "socks_proxy", opt_stringptr,
159 (void *)offsetof(smtp_transport_options_block, socks_proxy) }
162 ,{ "tls_certificate", opt_stringptr,
163 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
164 { "tls_crl", opt_stringptr,
165 (void *)offsetof(smtp_transport_options_block, tls_crl) },
166 { "tls_dh_min_bits", opt_int,
167 (void *)offsetof(smtp_transport_options_block, tls_dh_min_bits) },
168 { "tls_privatekey", opt_stringptr,
169 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
170 { "tls_require_ciphers", opt_stringptr,
171 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
172 { "tls_sni", opt_stringptr,
173 (void *)offsetof(smtp_transport_options_block, tls_sni) },
174 { "tls_tempfail_tryclear", opt_bool,
175 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
176 { "tls_try_verify_hosts", opt_stringptr,
177 (void *)offsetof(smtp_transport_options_block, tls_try_verify_hosts) },
178 { "tls_verify_cert_hostnames", opt_stringptr,
179 (void *)offsetof(smtp_transport_options_block,tls_verify_cert_hostnames)},
180 { "tls_verify_certificates", opt_stringptr,
181 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) },
182 { "tls_verify_hosts", opt_stringptr,
183 (void *)offsetof(smtp_transport_options_block, tls_verify_hosts) }
187 /* Size of the options list. An extern variable has to be used so that its
188 address can appear in the tables drtables.c. */
190 int smtp_transport_options_count =
191 sizeof(smtp_transport_options)/sizeof(optionlist);
193 /* Default private options block for the smtp transport. */
195 smtp_transport_options_block smtp_transport_option_defaults = {
197 NULL, /* fallback_hosts */
199 NULL, /* fallback_hostlist */
200 NULL, /* authenticated_sender */
201 US"$primary_hostname", /* helo_data */
202 NULL, /* interface */
204 US"smtp", /* protocol */
206 NULL, /* serialize_hosts */
207 NULL, /* hosts_try_auth */
208 NULL, /* hosts_require_auth */
209 US"*", /* hosts_try_chunking */
210 #ifdef EXPERIMENTAL_DANE
211 NULL, /* hosts_try_dane */
212 NULL, /* hosts_require_dane */
214 NULL, /* hosts_try_fastopen */
216 US"*", /* hosts_try_prdr */
219 US"*", /* hosts_request_ocsp (except under DANE; tls_client_start()) */
220 NULL, /* hosts_require_ocsp */
222 NULL, /* hosts_require_tls */
223 NULL, /* hosts_avoid_tls */
224 NULL, /* hosts_verify_avoid_tls */
225 NULL, /* hosts_avoid_pipelining */
226 NULL, /* hosts_avoid_esmtp */
227 NULL, /* hosts_nopass_tls */
228 5*60, /* command_timeout */
229 5*60, /* connect_timeout; shorter system default overrides */
230 5*60, /* data timeout */
231 10*60, /* final timeout */
232 1024, /* size_addition */
233 5, /* hosts_max_try */
234 50, /* hosts_max_try_hardlimit */
235 TRUE, /* address_retry_include_sender */
236 FALSE, /* allow_localhost */
237 FALSE, /* authenticated_sender_force */
238 FALSE, /* gethostbyname */
239 TRUE, /* dns_qualify_single */
240 FALSE, /* dns_search_parents */
241 { NULL, NULL }, /* dnssec_domains {request,require} */
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 /* socks_proxy */
253 ,NULL, /* tls_certificate */
255 NULL, /* tls_privatekey */
256 NULL, /* tls_require_ciphers */
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 */
273 FALSE} /* dot_stuffed */
277 /* some DSN flags for use later */
279 static int rf_list[] = {rf_notify_never, rf_notify_success,
280 rf_notify_failure, rf_notify_delay };
282 static uschar *rf_names[] = { US"NEVER", US"SUCCESS", US"FAILURE", US"DELAY" };
288 static uschar *smtp_command; /* Points to last cmd for error messages */
289 static uschar *mail_command; /* Points to MAIL cmd for error messages */
290 static uschar *data_command = US""; /* Points to DATA cmd for error messages */
291 static BOOL update_waiting; /* TRUE to update the "wait" database */
292 static BOOL pipelining_active; /* current transaction is in pipe mode */
295 /*************************************************
296 * Setup entry point *
297 *************************************************/
299 /* This function is called when the transport is about to be used,
300 but before running it in a sub-process. It is used for two things:
302 (1) To set the fallback host list in addresses, when delivering.
303 (2) To pass back the interface, port, protocol, and other options, for use
304 during callout verification.
307 tblock pointer to the transport instance block
308 addrlist list of addresses about to be transported
309 tf if not NULL, pointer to block in which to return options
310 uid the uid that will be set (not used)
311 gid the gid that will be set (not used)
312 errmsg place for error message (not used)
314 Returns: OK always (FAIL, DEFER not used)
318 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
319 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
321 smtp_transport_options_block *ob =
322 (smtp_transport_options_block *)(tblock->options_block);
324 errmsg = errmsg; /* Keep picky compilers happy */
328 /* Pass back options if required. This interface is getting very messy. */
332 tf->interface = ob->interface;
334 tf->protocol = ob->protocol;
335 tf->hosts = ob->hosts;
336 tf->hosts_override = ob->hosts_override;
337 tf->hosts_randomize = ob->hosts_randomize;
338 tf->gethostbyname = ob->gethostbyname;
339 tf->qualify_single = ob->dns_qualify_single;
340 tf->search_parents = ob->dns_search_parents;
341 tf->helo_data = ob->helo_data;
344 /* Set the fallback host list for all the addresses that don't have fallback
345 host lists, provided that the local host wasn't present in the original host
348 if (!testflag(addrlist, af_local_host_removed))
350 for (; addrlist != NULL; addrlist = addrlist->next)
351 if (addrlist->fallback_hosts == NULL)
352 addrlist->fallback_hosts = ob->fallback_hostlist;
360 /*************************************************
361 * Initialization entry point *
362 *************************************************/
364 /* Called for each instance, after its options have been read, to
365 enable consistency checks to be done, or anything else that needs
368 Argument: pointer to the transport instance block
373 smtp_transport_init(transport_instance *tblock)
375 smtp_transport_options_block *ob =
376 (smtp_transport_options_block *)(tblock->options_block);
378 /* Retry_use_local_part defaults FALSE if unset */
380 if (tblock->retry_use_local_part == TRUE_UNSET)
381 tblock->retry_use_local_part = FALSE;
383 /* Set the default port according to the protocol */
385 if (ob->port == NULL)
386 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
387 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
389 /* Set up the setup entry point, to be called before subprocesses for this
392 tblock->setup = smtp_transport_setup;
394 /* Complain if any of the timeouts are zero. */
396 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
397 ob->final_timeout <= 0)
398 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
399 "command, data, or final timeout value is zero for %s transport",
402 /* If hosts_override is set and there are local hosts, set the global
403 flag that stops verify from showing router hosts. */
405 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
407 /* If there are any fallback hosts listed, build a chain of host items
408 for them, but do not do any lookups at this time. */
410 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
417 /*************************************************
418 * Set delivery info into all active addresses *
419 *************************************************/
421 /* Only addresses whose status is >= PENDING are relevant. A lesser
422 status means that an address is not currently being processed.
425 addrlist points to a chain of addresses
426 errno_value to put in each address's errno field
427 msg to put in each address's message field
428 rc to put in each address's transport_return field
429 pass_message if TRUE, set the "pass message" flag in the address
430 host if set, mark addrs as having used this host
431 smtp_greeting from peer
432 helo_response from peer
434 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
435 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
436 this particular type of timeout.
442 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
443 BOOL pass_message, host_item * host
444 #ifdef EXPERIMENTAL_DSN_INFO
445 , const uschar * smtp_greeting, const uschar * helo_response
451 if (errno_value == ERRNO_CONNECTTIMEOUT)
453 errno_value = ETIMEDOUT;
454 orvalue = RTEF_CTOUT;
456 for (addr = addrlist; addr; 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;
469 addr->host_used = host;
470 #ifdef EXPERIMENTAL_DSN_INFO
472 {uschar * s = Ustrchr(smtp_greeting, '\n'); if (s) *s = '\0';}
473 addr->smtp_greeting = smtp_greeting;
476 {uschar * s = Ustrchr(helo_response, '\n'); if (s) *s = '\0';}
477 addr->helo_response = helo_response;
484 set_errno_nohost(address_item *addrlist, int errno_value, uschar *msg, int rc,
487 set_errno(addrlist, errno_value, msg, rc, pass_message, NULL
488 #ifdef EXPERIMENTAL_DSN_INFO
495 /*************************************************
496 * Check an SMTP response *
497 *************************************************/
499 /* This function is given an errno code and the SMTP response buffer
500 to analyse, together with the host identification for generating messages. It
501 sets an appropriate message and puts the first digit of the response code into
502 the yield variable. If no response was actually read, a suitable digit is
506 host the current host, to get its name for messages
507 errno_value pointer to the errno value
508 more_errno from the top address for use with ERRNO_FILTER_FAIL
509 buffer the SMTP response buffer
510 yield where to put a one-digit SMTP response code
511 message where to put an errror message
512 pass_message set TRUE if message is an SMTP response
514 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
518 check_response(host_item *host, int *errno_value, int more_errno,
519 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
521 uschar * pl = pipelining_active ? US"pipelined " : US"";
523 *yield = '4'; /* Default setting is to give a temporary error */
525 /* Handle response timeout */
527 if (*errno_value == ETIMEDOUT)
529 *message = US string_sprintf("SMTP timeout after %s%s",
531 if (transport_count > 0)
532 *message = US string_sprintf("%s (%d bytes written)", *message,
537 /* Handle malformed SMTP response */
539 if (*errno_value == ERRNO_SMTPFORMAT)
541 const uschar *malfresp = string_printing(buffer);
542 while (isspace(*malfresp)) malfresp++;
543 *message = *malfresp == 0
544 ? string_sprintf("Malformed SMTP reply (an empty line) "
545 "in response to %s%s", pl, smtp_command)
546 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
547 pl, smtp_command, malfresp);
551 /* Handle a failed filter process error; can't send QUIT as we mustn't
554 if (*errno_value == ERRNO_FILTER_FAIL)
556 *message = US string_sprintf("transport filter process failed (%d)%s",
558 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
562 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
565 if (*errno_value == ERRNO_CHHEADER_FAIL)
568 US string_sprintf("failed to expand headers_add or headers_remove: %s",
569 expand_string_message);
573 /* Handle failure to write a complete data block */
575 if (*errno_value == ERRNO_WRITEINCOMPLETE)
577 *message = US string_sprintf("failed to write a data block");
582 /* Handle lack of advertised SMTPUTF8, for international message */
583 if (*errno_value == ERRNO_UTF8_FWD)
585 *message = US string_sprintf("utf8 support required but not offered for forwarding");
586 DEBUG(D_deliver|D_transport) debug_printf("%s\n", *message);
591 /* Handle error responses from the remote mailer. */
595 const uschar *s = string_printing(buffer);
596 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
597 "%s", pl, smtp_command, s);
598 *pass_message = TRUE;
603 /* No data was read. If there is no errno, this must be the EOF (i.e.
604 connection closed) case, which causes deferral. An explicit connection reset
605 error has the same effect. Otherwise, put the host's identity in the message,
606 leaving the errno value to be interpreted as well. In all cases, we have to
607 assume the connection is now dead. */
609 if (*errno_value == 0 || *errno_value == ECONNRESET)
611 *errno_value = ERRNO_SMTPCLOSED;
612 *message = US string_sprintf("Remote host closed connection "
613 "in response to %s%s", pl, smtp_command);
615 else *message = US string_sprintf("%s [%s]", host->name, host->address);
622 /*************************************************
623 * Write error message to logs *
624 *************************************************/
626 /* This writes to the main log and to the message log.
629 addr the address item containing error information
630 host the current host
636 write_logs(address_item *addr, host_item *host)
638 uschar * message = LOGGING(outgoing_port)
639 ? string_sprintf("H=%s [%s]:%d", host->name, host->address,
640 host->port == PORT_NONE ? 25 : host->port)
641 : string_sprintf("H=%s [%s]", host->name, host->address);
645 message = string_sprintf("%s: %s", message, addr->message);
646 if (addr->basic_errno > 0)
647 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
648 log_write(0, LOG_MAIN, "%s", message);
649 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
653 const uschar * s = exim_errstr(addr->basic_errno);
654 log_write(0, LOG_MAIN, "%s %s", message, s);
655 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), message, s);
660 msglog_line(host_item * host, uschar * message)
662 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
663 host->name, host->address, message);
668 #ifndef DISABLE_EVENT
669 /*************************************************
670 * Post-defer action *
671 *************************************************/
673 /* This expands an arbitrary per-transport string.
674 It might, for example, be used to write to the database log.
677 addr the address item containing error information
678 host the current host
684 deferred_event_raise(address_item *addr, host_item *host)
686 uschar * action = addr->transport->event_action;
687 const uschar * save_domain;
693 save_domain = deliver_domain;
694 save_local = deliver_localpart;
696 /*XXX would ip & port already be set up? */
697 deliver_host_address = string_copy(host->address);
698 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
699 event_defer_errno = addr->basic_errno;
701 router_name = addr->router->name;
702 transport_name = addr->transport->name;
703 deliver_domain = addr->domain;
704 deliver_localpart = addr->local_part;
706 (void) event_raise(action, US"msg:host:defer",
708 ? addr->basic_errno > 0
709 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
710 : string_copy(addr->message)
711 : addr->basic_errno > 0
712 ? string_copy(US strerror(addr->basic_errno))
715 deliver_localpart = save_local;
716 deliver_domain = save_domain;
717 router_name = transport_name = NULL;
721 /*************************************************
722 * Synchronize SMTP responses *
723 *************************************************/
725 /* This function is called from smtp_deliver() to receive SMTP responses from
726 the server, and match them up with the commands to which they relate. When
727 PIPELINING is not in use, this function is called after every command, and is
728 therefore somewhat over-engineered, but it is simpler to use a single scheme
729 that works both with and without PIPELINING instead of having two separate sets
732 The set of commands that are buffered up with pipelining may start with MAIL
733 and may end with DATA; in between are RCPT commands that correspond to the
734 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
735 etc.) are never buffered.
737 Errors after MAIL or DATA abort the whole process leaving the response in the
738 buffer. After MAIL, pending responses are flushed, and the original command is
739 re-instated in big_buffer for error messages. For RCPT commands, the remote is
740 permitted to reject some recipient addresses while accepting others. However
741 certain errors clearly abort the whole process. Set the value in
742 transport_return to PENDING_OK if the address is accepted. If there is a
743 subsequent general error, it will get reset accordingly. If not, it will get
744 converted to OK at the end.
747 addrlist the complete address list
748 include_affixes TRUE if affixes include in RCPT
749 sync_addr ptr to the ptr of the one to start scanning at (updated)
750 host the host we are connected to
751 count the number of responses to read
753 include_sender true if 4xx retry is to include the sender it its key
754 pending_MAIL true if the first response is for MAIL
755 pending_DATA 0 if last command sent was not DATA
756 +1 if previously had a good recipient
757 -1 if not previously had a good recipient
758 inblock incoming SMTP block
759 timeout timeout value
760 buffer buffer for reading response
761 buffsize size of buffer
763 Returns: 3 if at least one address had 2xx and one had 5xx
764 2 if at least one address had 5xx but none had 2xx
765 1 if at least one host had a 2xx response, but none had 5xx
766 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
767 -1 timeout while reading RCPT response
768 -2 I/O or other non-response error for RCPT
769 -3 DATA or MAIL failed - errno and buffer set
773 sync_responses(address_item *addrlist, BOOL include_affixes,
774 address_item **sync_addr, host_item *host, int count,
775 BOOL address_retry_include_sender, BOOL pending_MAIL,
776 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
779 address_item *addr = *sync_addr;
782 /* Handle the response for a MAIL command. On error, reinstate the original
783 command in big_buffer for error message use, and flush any further pending
784 responses before returning, except after I/O errors and timeouts. */
789 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
791 DEBUG(D_transport) debug_printf("bad response for MAIL\n");
792 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
793 if (errno == 0 && buffer[0] != 0)
795 uschar flushbuffer[4096];
797 if (buffer[0] == '4')
799 save_errno = ERRNO_MAIL4XX;
800 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
804 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
806 && (errno != 0 || flushbuffer[0] == 0))
812 if (pending_DATA) count--; /* Number of RCPT responses to come */
813 while (count-- > 0) /* Mark any pending addrs with the host used */
815 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
816 addr->host_used = host;
823 if (pending_DATA) count--; /* Number of RCPT responses to come */
825 /* Read and handle the required number of RCPT responses, matching each one up
826 with an address by scanning for the next address whose status is PENDING_DEFER.
831 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
833 /* The address was accepted */
834 addr->host_used = host;
836 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
839 addr->transport_return = PENDING_OK;
841 /* If af_dr_retry_exists is set, there was a routing delay on this address;
842 ensure that any address-specific retry record is expunged. We do this both
843 for the basic key and for the version that also includes the sender. */
845 if (testflag(addr, af_dr_retry_exists))
847 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
849 retry_add_item(addr, altkey, rf_delete);
850 retry_add_item(addr, addr->address_retry_key, rf_delete);
854 /* Timeout while reading the response */
856 else if (errno == ETIMEDOUT)
858 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
859 transport_rcpt_address(addr, include_affixes));
860 set_errno_nohost(addrlist, ETIMEDOUT, message, DEFER, FALSE);
861 retry_add_item(addr, addr->address_retry_key, 0);
862 update_waiting = FALSE;
866 /* Handle other errors in obtaining an SMTP response by returning -1. This
867 will cause all the addresses to be deferred. Restore the SMTP command in
868 big_buffer for which we are checking the response, so the error message
871 else if (errno != 0 || buffer[0] == 0)
873 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
874 transport_rcpt_address(addr, include_affixes));
878 /* Handle SMTP permanent and temporary response codes. */
883 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
884 "%s", transport_rcpt_address(addr, include_affixes),
885 string_printing(buffer));
886 setflag(addr, af_pass_message);
887 msglog_line(host, addr->message);
889 /* The response was 5xx */
891 if (buffer[0] == '5')
893 addr->transport_return = FAIL;
897 /* The response was 4xx */
901 addr->transport_return = DEFER;
902 addr->basic_errno = ERRNO_RCPT4XX;
903 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
905 #ifndef DISABLE_EVENT
906 event_defer_errno = addr->more_errno;
907 msg_event_raise(US"msg:rcpt:host:defer", addr);
910 /* Log temporary errors if there are more hosts to be tried.
911 If not, log this last one in the == line. */
914 log_write(0, LOG_MAIN, "H=%s [%s]: %s", host->name, host->address, addr->message);
916 #ifndef DISABLE_EVENT
918 msg_event_raise(US"msg:rcpt:defer", addr);
921 /* Do not put this message on the list of those waiting for specific
922 hosts, as otherwise it is likely to be tried too often. */
924 update_waiting = FALSE;
926 /* Add a retry item for the address so that it doesn't get tried again
927 too soon. If address_retry_include_sender is true, add the sender address
930 if (address_retry_include_sender)
932 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
934 retry_add_item(addr, altkey, 0);
936 else retry_add_item(addr, addr->address_retry_key, 0);
939 } /* Loop for next RCPT response */
941 /* Update where to start at for the next block of responses, unless we
942 have already handled all the addresses. */
944 if (addr != NULL) *sync_addr = addr->next;
946 /* Handle a response to DATA. If we have not had any good recipients, either
947 previously or in this block, the response is ignored. */
949 if (pending_DATA != 0 &&
950 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
955 if (pending_DATA > 0 || (yield & 1) != 0)
957 if (errno == 0 && buffer[0] == '4')
959 errno = ERRNO_DATA4XX;
960 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
964 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
965 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
966 "is in use and there were no good recipients\n", msg);
969 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
970 present) received 3xx. If any RCPTs were handled and yielded anything other
971 than 4xx, yield will be set non-zero. */
978 /* Do the client side of smtp-level authentication */
981 buffer EHLO response from server (gets overwritten)
982 addrlist chain of potential addresses to deliver
983 host host to deliver to
985 ibp, obp comms channel control blocks
988 OK Success, or failed (but not required): global "smtp_authenticated" set
989 DEFER Failed authentication (and was required)
990 ERROR Internal problem
992 FAIL_SEND Failed communications - transmit
997 smtp_auth(uschar *buffer, unsigned bufsize, address_item *addrlist, host_item *host,
998 smtp_transport_options_block *ob, BOOL is_esmtp,
999 smtp_inblock *ibp, smtp_outblock *obp)
1002 uschar *fail_reason = US"server did not advertise AUTH support";
1004 smtp_authenticated = FALSE;
1005 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
1006 require_auth = verify_check_given_host(&ob->hosts_require_auth, host);
1008 if (is_esmtp && !regex_AUTH) regex_AUTH =
1009 regex_must_compile(US"\\n250[\\s\\-]AUTH\\s+([\\-\\w\\s]+)(?:\\n|$)",
1012 if (is_esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
1014 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
1015 expand_nmax = -1; /* reset */
1017 /* Must not do this check until after we have saved the result of the
1018 regex match above. */
1020 if (require_auth == OK ||
1021 verify_check_given_host(&ob->hosts_try_auth, host) == OK)
1024 fail_reason = US"no common mechanisms were found";
1026 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1028 /* Scan the configured authenticators looking for one which is configured
1029 for use as a client, which is not suppressed by client_condition, and
1030 whose name matches an authentication mechanism supported by the server.
1031 If one is found, attempt to authenticate by calling its client function.
1034 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1038 (au->client_condition != NULL &&
1039 !expand_check_condition(au->client_condition, au->name,
1040 US"client authenticator")))
1042 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1044 (au->client)? "client_condition is false" :
1045 "not configured as a client");
1049 /* Loop to scan supported server mechanisms */
1054 int len = Ustrlen(au->public_name);
1055 while (isspace(*p)) p++;
1057 if (strncmpic(au->public_name, p, len) != 0 ||
1058 (p[len] != 0 && !isspace(p[len])))
1060 while (*p != 0 && !isspace(*p)) p++;
1064 /* Found data for a listed mechanism. Call its client entry. Set
1065 a flag in the outblock so that data is overwritten after sending so
1066 that reflections don't show it. */
1068 fail_reason = US"authentication attempt(s) failed";
1069 obp->authenticating = TRUE;
1070 rc = (au->info->clientcode)(au, ibp, obp,
1071 ob->command_timeout, buffer, bufsize);
1072 obp->authenticating = FALSE;
1073 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1076 /* A temporary authentication failure must hold up delivery to
1077 this host. After a permanent authentication failure, we carry on
1078 to try other authentication methods. If all fail hard, try to
1079 deliver the message unauthenticated unless require_auth was set. */
1084 smtp_authenticated = TRUE; /* stops the outer loop */
1085 client_authenticator = au->name;
1086 if (au->set_client_id != NULL)
1087 client_authenticated_id = expand_string(au->set_client_id);
1090 /* Failure after writing a command */
1095 /* Failure after reading a response */
1098 if (errno != 0 || buffer[0] != '5') return FAIL;
1099 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1100 au->name, host->name, host->address, buffer);
1103 /* Failure by some other means. In effect, the authenticator
1104 decided it wasn't prepared to handle this case. Typically this
1105 is the result of "fail" in an expansion string. Do we need to
1106 log anything here? Feb 2006: a message is now put in the buffer
1107 if logging is required. */
1111 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1112 "authentication H=%s [%s] %s", au->name, host->name,
1113 host->address, buffer);
1116 /* Internal problem, message in buffer. */
1119 set_errno_nohost(addrlist, ERRNO_AUTHPROB, string_copy(buffer),
1124 break; /* If not authenticated, try next authenticator */
1125 } /* Loop for scanning supported server mechanisms */
1126 } /* Loop for further authenticators */
1130 /* If we haven't authenticated, but are required to, give up. */
1132 if (require_auth == OK && !smtp_authenticated)
1134 set_errno_nohost(addrlist, ERRNO_AUTHFAIL,
1135 string_sprintf("authentication required but %s", fail_reason), DEFER,
1144 /* Construct AUTH appendix string for MAIL TO */
1147 buffer to build string
1148 addrlist chain of potential addresses to deliver
1149 ob transport options
1151 Globals smtp_authenticated
1152 client_authenticated_sender
1153 Return True on error, otherwise buffer has (possibly empty) terminated string
1157 smtp_mail_auth_str(uschar *buffer, unsigned bufsize, address_item *addrlist,
1158 smtp_transport_options_block *ob)
1160 uschar *local_authenticated_sender = authenticated_sender;
1163 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n", authenticated_sender, ob->authenticated_sender, smtp_authenticated?"Y":"N");
1166 if (ob->authenticated_sender != NULL)
1168 uschar *new = expand_string(ob->authenticated_sender);
1171 if (!expand_string_forcedfail)
1173 uschar *message = string_sprintf("failed to expand "
1174 "authenticated_sender: %s", expand_string_message);
1175 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1179 else if (new[0] != 0) local_authenticated_sender = new;
1182 /* Add the authenticated sender address if present */
1184 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1185 local_authenticated_sender != NULL)
1187 string_format(buffer, bufsize, " AUTH=%s",
1188 auth_xtextencode(local_authenticated_sender,
1189 Ustrlen(local_authenticated_sender)));
1190 client_authenticated_sender = string_copy(local_authenticated_sender);
1200 #ifdef EXPERIMENTAL_DANE
1201 /* Lookup TLSA record for host/port.
1202 Return: OK success with dnssec; DANE mode
1203 DEFER Do not use this host now, may retry later
1204 FAIL_FORCED No TLSA record; DANE not usable
1205 FAIL Do not use this connection
1209 tlsa_lookup(const host_item * host, dns_answer * dnsa, BOOL dane_required)
1211 /* move this out to host.c given the similarity to dns_lookup() ? */
1213 const uschar * fullname = buffer;
1215 /* TLSA lookup string */
1216 (void)sprintf(CS buffer, "_%d._tcp.%.256s", host->port, host->name);
1218 switch (dns_lookup(dnsa, buffer, T_TLSA, &fullname))
1221 if (!dns_is_secure(dnsa))
1223 log_write(0, LOG_MAIN, "DANE error: TLSA lookup not DNSSEC");
1229 return DEFER; /* just defer this TLS'd conn */
1231 case DNS_NODATA: /* no TLSA RR for this lookup */
1232 case DNS_NOMATCH: /* no records at all for this lookup */
1233 return dane_required ? FAIL : FAIL_FORCED;
1237 return dane_required ? FAIL : DEFER;
1244 typedef struct smtp_compare_s
1246 uschar *current_sender_address;
1247 struct transport_instance *tblock;
1251 Create a unique string that identifies this message, it is based on
1252 sender_address, helo_data and tls_certificate if enabled. */
1255 smtp_local_identity(uschar * sender, struct transport_instance * tblock)
1257 address_item * addr1;
1258 uschar * if1 = US"";
1259 uschar * helo1 = US"";
1261 uschar * tlsc1 = US"";
1263 uschar * save_sender_address = sender_address;
1264 uschar * local_identity = NULL;
1265 smtp_transport_options_block * ob =
1266 (smtp_transport_options_block *)tblock->options_block;
1268 sender_address = sender;
1270 addr1 = deliver_make_addr (sender, TRUE);
1271 deliver_set_expansions(addr1);
1274 if1 = expand_string(ob->interface);
1277 helo1 = expand_string(ob->helo_data);
1280 if (ob->tls_certificate)
1281 tlsc1 = expand_string(ob->tls_certificate);
1282 local_identity = string_sprintf ("%s^%s^%s", if1, helo1, tlsc1);
1284 local_identity = string_sprintf ("%s^%s", if1, helo1);
1287 deliver_set_expansions(NULL);
1288 sender_address = save_sender_address;
1290 return local_identity;
1295 /* This routine is a callback that is called from transport_check_waiting.
1296 This function will evaluate the incoming message versus the previous
1297 message. If the incoming message is using a different local identity then
1298 we will veto this new message. */
1301 smtp_are_same_identities(uschar * message_id, smtp_compare_t * s_compare)
1303 uschar * message_local_identity,
1304 * current_local_identity,
1305 * new_sender_address;
1307 current_local_identity =
1308 smtp_local_identity(s_compare->current_sender_address, s_compare->tblock);
1310 if (!(new_sender_address = deliver_get_sender_address(message_id)))
1313 message_local_identity =
1314 smtp_local_identity(new_sender_address, s_compare->tblock);
1316 return Ustrcmp(current_local_identity, message_local_identity) == 0;
1322 ehlo_response(uschar * buf, size_t bsize, uschar checks)
1325 if ( checks & PEER_OFFERED_TLS
1326 && pcre_exec(regex_STARTTLS, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1327 checks &= ~PEER_OFFERED_TLS;
1330 if ( checks & PEER_OFFERED_IGNQ
1331 && pcre_exec(regex_IGNOREQUOTA, NULL, CS buf, bsize, 0,
1332 PCRE_EOPT, NULL, 0) < 0)
1333 checks &= ~PEER_OFFERED_IGNQ;
1335 if ( checks & PEER_OFFERED_CHUNKING
1336 && pcre_exec(regex_CHUNKING, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1337 checks &= ~PEER_OFFERED_CHUNKING;
1339 #ifndef DISABLE_PRDR
1340 if ( checks & PEER_OFFERED_PRDR
1341 && pcre_exec(regex_PRDR, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1342 checks &= ~PEER_OFFERED_PRDR;
1346 if ( checks & PEER_OFFERED_UTF8
1347 && pcre_exec(regex_UTF8, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1348 checks &= ~PEER_OFFERED_UTF8;
1351 if ( checks & PEER_OFFERED_DSN
1352 && pcre_exec(regex_DSN, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1353 checks &= ~PEER_OFFERED_DSN;
1355 if ( checks & PEER_OFFERED_PIPE
1356 && pcre_exec(regex_PIPELINING, NULL, CS buf, bsize, 0,
1357 PCRE_EOPT, NULL, 0) < 0)
1358 checks &= ~PEER_OFFERED_PIPE;
1360 if ( checks & PEER_OFFERED_SIZE
1361 && pcre_exec(regex_SIZE, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1362 checks &= ~PEER_OFFERED_SIZE;
1369 /* Callback for emitting a BDAT data chunk header.
1371 If given a nonzero size, first flush any buffered SMTP commands
1372 then emit the command.
1374 Reap previous SMTP command responses if requested.
1375 Reap one SMTP command response if requested.
1377 Returns: OK or ERROR
1381 smtp_chunk_cmd_callback(int fd, transport_ctx * tctx,
1382 unsigned chunk_size, unsigned flags)
1384 smtp_transport_options_block * ob =
1385 (smtp_transport_options_block *)(tctx->tblock->options_block);
1388 uschar * buffer = tctx->buffer;
1391 /* Write SMTP chunk header command */
1395 if((cmd_count = smtp_write_command(tctx->outblock, FALSE, "BDAT %u%s\r\n",
1397 flags & tc_chunk_last ? " LAST" : "")
1398 ) < 0) return ERROR;
1399 if (flags & tc_chunk_last)
1400 data_command = string_copy(big_buffer); /* Save for later error message */
1403 prev_cmd_count = cmd_count += tctx->cmd_count;
1405 /* Reap responses for any previous, but not one we just emitted */
1409 if (tctx->pending_BDAT)
1412 if (flags & tc_reap_prev && prev_cmd_count > 0)
1414 DEBUG(D_transport) debug_printf("look for %d responses"
1415 " for previous pipelined cmds\n", prev_cmd_count);
1417 switch(sync_responses(tctx->first_addr, tctx->tblock->rcpt_include_affixes,
1418 tctx->sync_addr, tctx->host, prev_cmd_count,
1419 ob->address_retry_include_sender,
1420 tctx->pending_MAIL, 0,
1422 ob->command_timeout,
1423 buffer, DELIVER_BUFFER_SIZE))
1425 case 1: /* 2xx (only) => OK */
1426 case 3: tctx->good_RCPT = TRUE; /* 2xx & 5xx => OK & progress made */
1427 case 2: *tctx->completed_address = TRUE; /* 5xx (only) => progress made */
1428 case 0: break; /* No 2xx or 5xx, but no probs */
1430 case -1: /* Timeout on RCPT */
1431 default: return ERROR; /* I/O error, or any MAIL/DATA error */
1434 if (!tctx->pending_BDAT)
1435 pipelining_active = FALSE;
1438 /* Reap response for an outstanding BDAT */
1440 if (tctx->pending_BDAT)
1442 DEBUG(D_transport) debug_printf("look for one response for BDAT\n");
1444 if (!smtp_read_response(tctx->inblock, buffer, DELIVER_BUFFER_SIZE, '2',
1445 ob->command_timeout))
1447 if (errno == 0 && buffer[0] == '4')
1449 errno = ERRNO_DATA4XX; /*XXX does this actually get used? */
1450 tctx->first_addr->more_errno |=
1451 ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1456 tctx->pending_BDAT = FALSE;
1457 pipelining_active = FALSE;
1459 else if (chunk_size > 0)
1460 tctx->pending_BDAT = TRUE;
1463 tctx->cmd_count = cmd_count;
1469 /*************************************************
1470 * Deliver address list to given host *
1471 *************************************************/
1473 /* If continue_hostname is not null, we get here only when continuing to
1474 deliver down an existing channel. The channel was passed as the standard
1475 input. TLS is never active on a passed channel; the previous process always
1476 closes it down before passing the connection on.
1478 Otherwise, we have to make a connection to the remote host, and do the
1479 initial protocol exchange.
1481 When running as an MUA wrapper, if the sender or any recipient is rejected,
1482 temporarily or permanently, we force failure for all recipients.
1485 addrlist chain of potential addresses to deliver; only those whose
1486 transport_return field is set to PENDING_DEFER are currently
1487 being processed; others should be skipped - they have either
1488 been delivered to an earlier host or IP address, or been
1489 failed by one of them.
1490 host host to deliver to
1491 host_af AF_INET or AF_INET6
1492 port default TCP/IP port to use, in host byte order
1493 interface interface to bind to, or NULL
1494 tblock transport instance block
1495 message_defer set TRUE if yield is OK, but all addresses were deferred
1496 because of a non-recipient, non-host failure, that is, a
1497 4xx response to MAIL FROM, DATA, or ".". This is a defer
1498 that is specific to the message.
1499 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1500 a second attempt after TLS initialization fails
1502 Returns: OK - the connection was made and the delivery attempted;
1503 the result for each address is in its data block.
1504 DEFER - the connection could not be made, or something failed
1505 while setting up the SMTP session, or there was a
1506 non-message-specific error, such as a timeout.
1507 ERROR - a filter command is specified for this transport,
1508 and there was a problem setting it up; OR helo_data
1509 or add_headers or authenticated_sender is specified
1510 for this transport, and the string failed to expand
1514 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
1515 uschar *interface, transport_instance *tblock,
1516 BOOL *message_defer, BOOL suppress_tls)
1519 address_item *sync_addr;
1520 address_item *first_addr = addrlist;
1525 time_t start_delivery_time = time(NULL);
1526 smtp_transport_options_block *ob =
1527 (smtp_transport_options_block *)(tblock->options_block);
1537 BOOL pending_MAIL:1;
1538 #ifndef DISABLE_PRDR
1544 BOOL dsn_all_lasthop:1;
1545 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1547 BOOL dane_required:1;
1551 BOOL pass_message = FALSE;
1552 BOOL completed_address = FALSE;
1553 uschar peer_offered = 0;
1554 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1555 dns_answer tlsa_dnsa;
1557 smtp_inblock inblock;
1558 smtp_outblock outblock;
1559 int max_rcpt = tblock->max_addresses;
1560 uschar *igquotstr = US"";
1562 #ifdef EXPERIMENTAL_DSN_INFO
1563 uschar *smtp_greeting = NULL;
1564 uschar *helo_response = NULL;
1566 uschar *helo_data = NULL;
1568 uschar *message = NULL;
1569 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
1571 uschar buffer[DELIVER_BUFFER_SIZE];
1572 uschar inbuffer[4096];
1573 uschar outbuffer[4096];
1575 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
1577 lflags.lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
1578 lflags.smtps = strcmpic(ob->protocol, US"smtps") == 0;
1580 lflags.send_rset = TRUE;
1581 lflags.send_quit = TRUE;
1582 lflags.setting_up = TRUE;
1583 lflags.esmtp = TRUE;
1584 lflags.esmtp_sent = FALSE;
1586 lflags.utf8_needed = FALSE;
1588 lflags.dsn_all_lasthop = TRUE;
1589 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1590 lflags.dane = FALSE;
1591 lflags.dane_required = verify_check_given_host(&ob->hosts_require_dane, host) == OK;
1594 *message_defer = FALSE;
1595 smtp_command = US"initial connection";
1597 if (max_rcpt == 0) max_rcpt = 999999;
1599 /* Set up the buffer for reading SMTP response packets. */
1601 inblock.buffer = inbuffer;
1602 inblock.buffersize = sizeof(inbuffer);
1603 inblock.ptr = inbuffer;
1604 inblock.ptrend = inbuffer;
1606 /* Set up the buffer for holding SMTP commands while pipelining */
1608 outblock.buffer = outbuffer;
1609 outblock.buffersize = sizeof(outbuffer);
1610 outblock.ptr = outbuffer;
1611 outblock.cmd_count = 0;
1612 outblock.authenticating = FALSE;
1614 /* Reset the parameters of a TLS session. */
1617 tls_out.cipher = NULL; /* the one we may use for this transport */
1618 tls_out.ourcert = NULL;
1619 tls_out.peercert = NULL;
1620 tls_out.peerdn = NULL;
1621 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1624 tls_out.ocsp = OCSP_NOT_REQ;
1626 /* Flip the legacy TLS-related variables over to the outbound set in case
1627 they're used in the context of the transport. Don't bother resetting
1628 afterward as we're in a subprocess. */
1630 tls_modify_variables(&tls_out);
1635 set_errno_nohost(addrlist, ERRNO_TLSFAILURE, US"TLS support not available",
1641 /* Make a connection to the host if this isn't a continued delivery, and handle
1642 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
1643 specially so they can be identified for retries. */
1645 if (continue_hostname == NULL)
1647 /* This puts port into host->port */
1648 inblock.sock = outblock.sock =
1649 smtp_connect(host, host_af, port, interface, ob->connect_timeout, tblock);
1651 if (inblock.sock < 0)
1653 set_errno_nohost(addrlist, errno == ETIMEDOUT ? ERRNO_CONNECTTIMEOUT : errno,
1654 NULL, DEFER, FALSE);
1658 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1660 tls_out.dane_verified = FALSE;
1661 tls_out.tlsa_usage = 0;
1663 if (host->dnssec == DS_YES)
1665 if( lflags.dane_required
1666 || verify_check_given_host(&ob->hosts_try_dane, host) == OK
1668 switch (rc = tlsa_lookup(host, &tlsa_dnsa, lflags.dane_required))
1670 case OK: lflags.dane = TRUE; break;
1671 case FAIL_FORCED: break;
1672 default: set_errno_nohost(addrlist, ERRNO_DNSDEFER,
1673 string_sprintf("DANE error: tlsa lookup %s",
1674 rc == DEFER ? "DEFER" : "FAIL"),
1679 else if (lflags.dane_required)
1681 set_errno_nohost(addrlist, ERRNO_DNSDEFER,
1682 string_sprintf("DANE error: %s lookup not DNSSEC", host->name),
1688 ob->tls_tempfail_tryclear = FALSE;
1692 /* Expand the greeting message while waiting for the initial response. (Makes
1693 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1694 delayed till here so that $sending_interface and $sending_port are set. */
1696 helo_data = expand_string(ob->helo_data);
1700 uschar * errstr = NULL;
1701 if ((helo_data = string_domain_utf8_to_alabel(helo_data, &errstr)), errstr)
1703 errstr = string_sprintf("failed to expand helo_data: %s", errstr);
1704 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE);
1711 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1712 is nevertheless a reasonably clean way of programming this kind of logic,
1713 where you want to escape on any error. */
1720 (void) setsockopt(inblock.sock, IPPROTO_TCP, TCP_QUICKACK, US &off, sizeof(off));
1722 good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
1723 '2', ob->command_timeout);
1724 #ifdef EXPERIMENTAL_DSN_INFO
1725 smtp_greeting = string_copy(buffer);
1727 if (!good_response) goto RESPONSE_FAILED;
1729 #ifndef DISABLE_EVENT
1732 lookup_dnssec_authenticated = host->dnssec==DS_YES ? US"yes"
1733 : host->dnssec==DS_NO ? US"no" : NULL;
1734 s = event_raise(tblock->event_action, US"smtp:connect", buffer);
1737 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL,
1738 string_sprintf("deferred by smtp:connect event expansion: %s", s),
1746 /* Now check if the helo_data expansion went well, and sign off cleanly if
1751 uschar *message = string_sprintf("failed to expand helo_data: %s",
1752 expand_string_message);
1753 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1759 /** Debugging without sending a message
1760 addrlist->transport_return = DEFER;
1764 /* Errors that occur after this point follow an SMTP command, which is
1765 left in big_buffer by smtp_write_command() for use in error messages. */
1767 smtp_command = big_buffer;
1769 /* Tell the remote who we are...
1771 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1772 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1773 greeting is of this form. The assumption was that the far end supports it
1774 properly... but experience shows that there are some that give 5xx responses,
1775 even though the banner includes "ESMTP" (there's a bloody-minded one that
1776 says "ESMTP not spoken here"). Cope with that case.
1778 September 2000: Time has passed, and it seems reasonable now to always send
1779 EHLO at the start. It is also convenient to make the change while installing
1782 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1783 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1784 would be no way to send out the mails, so there is now a host list
1785 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1786 PIPELINING problem as well. Maybe it can also be useful to cure other
1787 problems with broken servers.
1789 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1790 Then somebody tried it with a Microsoft mailer... It seems that all other
1791 mailers use upper case for some reason (the RFC is quite clear about case
1792 independence) so, for peace of mind, I gave in. */
1794 lflags.esmtp = verify_check_given_host(&ob->hosts_avoid_esmtp, host) != OK;
1796 /* Alas; be careful, since this goto is not an error-out, so conceivably
1797 we might set data between here and the target which we assume to exist
1798 and be usable. I can see this coming back to bite us. */
1802 smtp_peer_options |= PEER_OFFERED_TLS;
1803 suppress_tls = FALSE;
1804 ob->tls_tempfail_tryclear = FALSE;
1805 smtp_command = US"SSL-on-connect";
1812 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1813 lflags.lmtp ? "LHLO" : "EHLO", helo_data) < 0)
1815 lflags.esmtp_sent = TRUE;
1816 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1817 ob->command_timeout))
1819 if (errno != 0 || buffer[0] == 0 || lflags.lmtp)
1821 #ifdef EXPERIMENTAL_DSN_INFO
1822 helo_response = string_copy(buffer);
1824 goto RESPONSE_FAILED;
1826 lflags.esmtp = FALSE;
1828 #ifdef EXPERIMENTAL_DSN_INFO
1829 helo_response = string_copy(buffer);
1834 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1839 int n = sizeof(buffer);
1840 uschar * rsp = buffer;
1842 if (lflags.esmtp_sent && (n = Ustrlen(buffer)) < sizeof(buffer)/2)
1843 { rsp = buffer + n + 1; n = sizeof(buffer) - n; }
1845 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1847 good_response = smtp_read_response(&inblock, rsp, n,
1848 '2', ob->command_timeout);
1849 #ifdef EXPERIMENTAL_DSN_INFO
1850 helo_response = string_copy(rsp);
1854 /* Handle special logging for a closed connection after HELO
1855 when had previously sent EHLO */
1857 if (rsp != buffer && rsp[0] == 0 && (errno == 0 || errno == ECONNRESET))
1860 lflags.send_quit = FALSE;
1861 save_errno = ERRNO_SMTPCLOSED;
1862 message = string_sprintf("Remote host closed connection "
1863 "in response to %s (EHLO response was: %s)",
1864 smtp_command, buffer);
1867 Ustrncpy(buffer, rsp, sizeof(buffer)/2);
1868 goto RESPONSE_FAILED;
1872 peer_offered = smtp_peer_options = 0;
1874 if (lflags.esmtp || lflags.lmtp)
1876 peer_offered = ehlo_response(buffer, Ustrlen(buffer),
1877 PEER_OFFERED_TLS /* others checked later */
1880 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1883 smtp_peer_options |= peer_offered & PEER_OFFERED_TLS;
1888 /* For continuing deliveries down the same channel, the socket is the standard
1889 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1890 below). Set up the pointer to where subsequent commands will be left, for
1891 error messages. Note that smtp_peer_options will have been
1892 set from the command line if they were set in the process that passed the
1895 /*XXX continue case needs to propagate DSN_INFO, prob. in deliver.c
1896 as the contine goes via transport_pass_socket() and doublefork and exec.
1897 It does not wait. Unclear how we keep separate host's responses
1898 separate - we could match up by host ip+port as a bodge. */
1902 inblock.sock = outblock.sock = fileno(stdin);
1903 smtp_command = big_buffer;
1904 host->port = port; /* Record the port that was used */
1907 /* If TLS is available on this connection, whether continued or not, attempt to
1908 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1909 send another EHLO - the server may give a different answer in secure mode. We
1910 use a separate buffer for reading the response to STARTTLS so that if it is
1911 negative, the original EHLO data is available for subsequent analysis, should
1912 the client not be required to use TLS. If the response is bad, copy the buffer
1913 for error analysis. */
1916 if ( smtp_peer_options & PEER_OFFERED_TLS
1918 && verify_check_given_host(&ob->hosts_avoid_tls, host) != OK)
1920 uschar buffer2[4096];
1921 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1924 /* If there is an I/O error, transmission of this message is deferred. If
1925 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1926 false, we also defer. However, if there is a temporary rejection of STARTTLS
1927 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1928 STARTTLS, we carry on. This means we will try to send the message in clear,
1929 unless the host is in hosts_require_tls (tested below). */
1931 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1932 ob->command_timeout))
1936 || (buffer2[0] == '4' && !ob->tls_tempfail_tryclear)
1939 Ustrncpy(buffer, buffer2, sizeof(buffer));
1940 goto RESPONSE_FAILED;
1944 /* STARTTLS accepted: try to negotiate a TLS session. */
1949 int rc = tls_client_start(inblock.sock, host, addrlist, tblock
1950 # ifdef EXPERIMENTAL_DANE
1951 , lflags.dane ? &tlsa_dnsa : NULL
1955 /* TLS negotiation failed; give an error. From outside, this function may
1956 be called again to try in clear on a new connection, if the options permit
1957 it for this host. */
1961 # ifdef EXPERIMENTAL_DANE
1962 if (lflags.dane) log_write(0, LOG_MAIN,
1963 "DANE attempt failed; no TLS connection to %s [%s]",
1964 host->name, host->address);
1967 save_errno = ERRNO_TLSFAILURE;
1968 message = US"failure while setting up TLS session";
1969 lflags.send_quit = FALSE;
1973 /* TLS session is set up */
1975 smtp_peer_options_wrap = smtp_peer_options;
1976 for (addr = addrlist; addr; addr = addr->next)
1977 if (addr->transport_return == PENDING_DEFER)
1979 addr->cipher = tls_out.cipher;
1980 addr->ourcert = tls_out.ourcert;
1981 addr->peercert = tls_out.peercert;
1982 addr->peerdn = tls_out.peerdn;
1983 addr->ocsp = tls_out.ocsp;
1988 /* if smtps, we'll have smtp_command set to something else; always safe to
1990 smtp_command = big_buffer;
1992 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1993 helo_data is null, we are dealing with a connection that was passed from
1994 another process, and so we won't have expanded helo_data above. We have to
1995 expand it here. $sending_ip_address and $sending_port are set up right at the
1996 start of the Exim process (in exim.c). */
1998 if (tls_out.active >= 0)
2003 if (helo_data == NULL)
2005 helo_data = expand_string(ob->helo_data);
2006 if (helo_data == NULL)
2008 uschar *message = string_sprintf("failed to expand helo_data: %s",
2009 expand_string_message);
2010 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
2016 /* For SMTPS we need to wait for the initial OK response. */
2019 good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
2020 '2', ob->command_timeout);
2021 #ifdef EXPERIMENTAL_DSN_INFO
2022 smtp_greeting = string_copy(buffer);
2024 if (!good_response) goto RESPONSE_FAILED;
2028 greeting_cmd = "EHLO";
2031 greeting_cmd = "HELO";
2033 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
2036 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
2037 lflags.lmtp ? "LHLO" : greeting_cmd, helo_data) < 0)
2039 good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
2040 '2', ob->command_timeout);
2041 #ifdef EXPERIMENTAL_DSN_INFO
2042 helo_response = string_copy(buffer);
2044 if (!good_response) goto RESPONSE_FAILED;
2045 smtp_peer_options = 0;
2048 /* If the host is required to use a secure channel, ensure that we
2051 else if ( lflags.smtps
2052 # ifdef EXPERIMENTAL_DANE
2055 || verify_check_given_host(&ob->hosts_require_tls, host) == OK
2058 save_errno = ERRNO_TLSREQUIRED;
2059 message = string_sprintf("a TLS session is required, but %s",
2060 smtp_peer_options & PEER_OFFERED_TLS
2061 ? "an attempt to start TLS failed" : "the server did not offer TLS support");
2064 #endif /*SUPPORT_TLS*/
2066 /* If TLS is active, we have just started it up and re-done the EHLO command,
2067 so its response needs to be analyzed. If TLS is not active and this is a
2068 continued session down a previously-used socket, we haven't just done EHLO, so
2071 if (continue_hostname == NULL
2073 || tls_out.active >= 0
2077 if (lflags.esmtp || lflags.lmtp)
2079 peer_offered = ehlo_response(buffer, Ustrlen(buffer),
2081 | (lflags.lmtp && ob->lmtp_ignore_quota ? PEER_OFFERED_IGNQ : 0)
2082 | PEER_OFFERED_CHUNKING
2085 | (addrlist->prop.utf8_msg ? PEER_OFFERED_UTF8 : 0)
2086 /*XXX if we hand peercaps on to continued-conn processes,
2087 must not depend on this addr */
2091 | (ob->size_addition >= 0 ? PEER_OFFERED_SIZE : 0)
2094 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
2095 lmtp_ignore_quota option was set. */
2097 igquotstr = peer_offered & PEER_OFFERED_IGNQ ? US" IGNOREQUOTA" : US"";
2099 /* If the response to EHLO specified support for the SIZE parameter, note
2100 this, provided size_addition is non-negative. */
2102 smtp_peer_options |= peer_offered & PEER_OFFERED_SIZE;
2104 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
2105 the current host, esmtp will be false, so PIPELINING can never be used. If
2106 the current host matches hosts_avoid_pipelining, don't do it. */
2108 if ( peer_offered & PEER_OFFERED_PIPE
2109 && verify_check_given_host(&ob->hosts_avoid_pipelining, host) != OK)
2110 smtp_peer_options |= PEER_OFFERED_PIPE;
2112 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
2113 smtp_peer_options & PEER_OFFERED_PIPE ? "" : "not ");
2115 if ( peer_offered & PEER_OFFERED_CHUNKING
2116 && verify_check_given_host(&ob->hosts_try_chunking, host) != OK)
2117 peer_offered &= ~PEER_OFFERED_CHUNKING;
2119 if (peer_offered & PEER_OFFERED_CHUNKING)
2120 {DEBUG(D_transport) debug_printf("CHUNKING usable\n");}
2122 #ifndef DISABLE_PRDR
2123 if ( peer_offered & PEER_OFFERED_PRDR
2124 && verify_check_given_host(&ob->hosts_try_prdr, host) != OK)
2125 peer_offered &= ~PEER_OFFERED_PRDR;
2127 if (peer_offered & PEER_OFFERED_PRDR)
2128 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
2131 /* Note if the server supports DSN */
2132 smtp_peer_options |= peer_offered & PEER_OFFERED_DSN;
2133 DEBUG(D_transport) debug_printf("%susing DSN\n",
2134 peer_offered & PEER_OFFERED_DSN ? "" : "not ");
2136 /* Note if the response to EHLO specifies support for the AUTH extension.
2137 If it has, check that this host is one we want to authenticate to, and do
2138 the business. The host name and address must be available when the
2139 authenticator's client driver is running. */
2141 switch (yield = smtp_auth(buffer, sizeof(buffer), addrlist, host,
2142 ob, lflags.esmtp, &inblock, &outblock))
2144 default: goto SEND_QUIT;
2146 case FAIL_SEND: goto SEND_FAILED;
2147 case FAIL: goto RESPONSE_FAILED;
2151 pipelining_active = !!(smtp_peer_options & PEER_OFFERED_PIPE);
2153 /* The setting up of the SMTP call is now complete. Any subsequent errors are
2154 message-specific. */
2156 lflags.setting_up = FALSE;
2159 if (addrlist->prop.utf8_msg)
2161 lflags.utf8_needed = !addrlist->prop.utf8_downcvt
2162 && !addrlist->prop.utf8_downcvt_maybe;
2163 DEBUG(D_transport) if (!lflags.utf8_needed)
2164 debug_printf("utf8: %s downconvert\n",
2165 addrlist->prop.utf8_downcvt ? "mandatory" : "optional");
2168 /* If this is an international message we need the host to speak SMTPUTF8 */
2169 if (lflags.utf8_needed && !(peer_offered & PEER_OFFERED_UTF8))
2171 errno = ERRNO_UTF8_FWD;
2172 goto RESPONSE_FAILED;
2176 /* If there is a filter command specified for this transport, we can now
2177 set it up. This cannot be done until the identify of the host is known. */
2179 if (tblock->filter_command != NULL)
2183 sprintf(CS fbuf, "%.50s transport", tblock->name);
2184 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
2185 TRUE, DEFER, addrlist, fbuf, NULL);
2186 transport_filter_timeout = tblock->filter_timeout;
2188 /* On failure, copy the error to all addresses, abandon the SMTP call, and
2193 set_errno_nohost(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
2199 if ( transport_filter_argv
2200 && *transport_filter_argv
2201 && **transport_filter_argv
2202 && peer_offered & PEER_OFFERED_CHUNKING
2205 peer_offered &= ~PEER_OFFERED_CHUNKING;
2206 DEBUG(D_transport) debug_printf("CHUNKING not usable due to transport filter\n");
2211 /* For messages that have more than the maximum number of envelope recipients,
2212 we want to send several transactions down the same SMTP connection. (See
2213 comments in deliver.c as to how this reconciles, heuristically, with
2214 remote_max_parallel.) This optimization was added to Exim after the following
2215 code was already working. The simplest way to put it in without disturbing the
2216 code was to use a goto to jump back to this point when there is another
2217 transaction to handle. */
2220 sync_addr = first_addr;
2223 lflags.send_rset = TRUE;
2224 completed_address = FALSE;
2227 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
2228 qualification, send it, adding something to the message size to allow for
2229 imprecision and things that get added en route. Exim keeps the number of lines
2230 in a message, so we can give an accurate value for the original message, but we
2231 need some additional to handle added headers. (Double "." characters don't get
2232 included in the count.) */
2237 if (peer_offered & PEER_OFFERED_SIZE)
2239 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
2243 #ifndef DISABLE_PRDR
2244 lflags.prdr_active = FALSE;
2245 if (peer_offered & PEER_OFFERED_PRDR)
2246 for (addr = first_addr; addr; addr = addr->next)
2247 if (addr->transport_return == PENDING_DEFER)
2249 for (addr = addr->next; addr; addr = addr->next)
2250 if (addr->transport_return == PENDING_DEFER)
2251 { /* at least two recipients to send */
2252 lflags.prdr_active = TRUE;
2253 sprintf(CS p, " PRDR"); p += 5;
2261 if ( addrlist->prop.utf8_msg
2262 && !addrlist->prop.utf8_downcvt
2263 && peer_offered & PEER_OFFERED_UTF8
2265 sprintf(CS p, " SMTPUTF8"), p += 9;
2268 /* check if all addresses have lasthop flag */
2269 /* do not send RET and ENVID if true */
2270 for (lflags.dsn_all_lasthop = TRUE, addr = first_addr;
2271 address_count < max_rcpt && addr != NULL;
2273 if ((addr->dsn_flags & rf_dsnlasthop) != 1)
2275 lflags.dsn_all_lasthop = FALSE;
2279 /* Add any DSN flags to the mail command */
2281 if (peer_offered & PEER_OFFERED_DSN && !lflags.dsn_all_lasthop)
2283 if (dsn_ret == dsn_ret_hdrs)
2284 { Ustrcpy(p, " RET=HDRS"); p += 9; }
2285 else if (dsn_ret == dsn_ret_full)
2286 { Ustrcpy(p, " RET=FULL"); p += 9; }
2290 string_format(p, sizeof(buffer) - (p-buffer), " ENVID=%s", dsn_envid);
2295 /* If an authenticated_sender override has been specified for this transport
2296 instance, expand it. If the expansion is forced to fail, and there was already
2297 an authenticated_sender for this message, the original value will be used.
2298 Other expansion failures are serious. An empty result is ignored, but there is
2299 otherwise no check - this feature is expected to be used with LMTP and other
2300 cases where non-standard addresses (e.g. without domains) might be required. */
2302 if (smtp_mail_auth_str(p, sizeof(buffer) - (p-buffer), addrlist, ob))
2308 /* From here until we send the DATA command, we can make use of PIPELINING
2309 if the server host supports it. The code has to be able to check the responses
2310 at any point, for when the buffer fills up, so we write it totally generally.
2311 When PIPELINING is off, each command written reports that it has flushed the
2314 lflags.pending_MAIL = TRUE; /* The block starts with MAIL */
2317 uschar * s = return_path;
2319 uschar * errstr = NULL;
2321 /* If we must downconvert, do the from-address here. Remember we had to
2322 for the to-addresses (done below), and also (ugly) for re-doing when building
2323 the delivery log line. */
2325 if ( addrlist->prop.utf8_msg
2326 && (addrlist->prop.utf8_downcvt || !(peer_offered & PEER_OFFERED_UTF8))
2329 if (s = string_address_utf8_to_alabel(return_path, &errstr), errstr)
2331 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE);
2335 setflag(addrlist, af_utf8_downcvt);
2339 rc = smtp_write_command(&outblock, pipelining_active,
2340 "MAIL FROM:<%s>%s\r\n", s, buffer);
2343 mail_command = string_copy(big_buffer); /* Save for later error message */
2347 case -1: /* Transmission error */
2350 case +1: /* Block was sent */
2351 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2352 ob->command_timeout))
2354 if (errno == 0 && buffer[0] == '4')
2356 errno = ERRNO_MAIL4XX;
2357 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2359 goto RESPONSE_FAILED;
2361 lflags.pending_MAIL = FALSE;
2365 /* Pass over all the relevant recipient addresses for this host, which are the
2366 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
2367 several before we have to read the responses for those seen so far. This
2368 checking is done by a subroutine because it also needs to be done at the end.
2369 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
2370 the next one if not all are sent.
2372 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
2373 last address because we want to abort if any recipients have any kind of
2374 problem, temporary or permanent. We know that all recipient addresses will have
2375 the PENDING_DEFER status, because only one attempt is ever made, and we know
2376 that max_rcpt will be large, so all addresses will be done at once. */
2378 for (addr = first_addr;
2379 addr && address_count < max_rcpt;
2381 if (addr->transport_return == PENDING_DEFER)
2387 addr->dsn_aware = peer_offered & PEER_OFFERED_DSN
2388 ? dsn_support_yes : dsn_support_no;
2391 no_flush = pipelining_active && (!mua_wrapper || addr->next);
2393 /* Add any DSN flags to the rcpt command and add to the sent string */
2398 if (peer_offered & PEER_OFFERED_DSN && !(addr->dsn_flags & rf_dsnlasthop))
2400 if (addr->dsn_flags & rf_dsnflags)
2404 Ustrcpy(p, " NOTIFY=");
2406 for (i = 0; i < 4; i++)
2407 if ((addr->dsn_flags & rf_list[i]) != 0)
2409 if (!first) *p++ = ',';
2411 Ustrcpy(p, rf_names[i]);
2416 if (addr->dsn_orcpt)
2418 string_format(p, sizeof(buffer) - (p-buffer), " ORCPT=%s",
2424 /* Now send the RCPT command, and process outstanding responses when
2425 necessary. After a timeout on RCPT, we just end the function, leaving the
2426 yield as OK, because this error can often mean that there is a problem with
2427 just one address, so we don't want to delay the host. */
2429 rcpt_addr = transport_rcpt_address(addr, tblock->rcpt_include_affixes);
2433 uschar * dummy_errstr;
2434 if ( testflag(addrlist, af_utf8_downcvt)
2435 && (rcpt_addr = string_address_utf8_to_alabel(rcpt_addr, &dummy_errstr),
2439 errno = ERRNO_EXPANDFAIL;
2445 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s%s\r\n",
2446 rcpt_addr, igquotstr, buffer);
2448 if (count < 0) goto SEND_FAILED;
2451 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
2452 &sync_addr, host, count, ob->address_retry_include_sender,
2453 lflags.pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
2456 case 3: lflags.ok = TRUE; /* 2xx & 5xx => OK & progress made */
2457 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2460 case 1: lflags.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2461 if (!lflags.lmtp) completed_address = TRUE; /* can't tell about progress yet */
2462 case 0: /* No 2xx or 5xx, but no probs */
2465 case -1: goto END_OFF; /* Timeout on RCPT */
2466 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
2468 lflags.pending_MAIL = FALSE; /* Dealt with MAIL */
2470 } /* Loop for next address */
2472 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
2473 permanently or temporarily. We should have flushed and synced after the last
2478 address_item *badaddr;
2479 for (badaddr = first_addr; badaddr; badaddr = badaddr->next)
2480 if (badaddr->transport_return != PENDING_OK)
2482 /*XXX could we find a better errno than 0 here? */
2483 set_errno_nohost(addrlist, 0, badaddr->message, FAIL,
2484 testflag(badaddr, af_pass_message));
2490 /* If ok is TRUE, we know we have got at least one good recipient, and must now
2491 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
2492 have a good recipient buffered up if we are pipelining. We don't want to waste
2493 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
2494 are pipelining. The responses are all handled by sync_responses().
2495 If using CHUNKING, do not send a BDAT until we know how big a chunk we want
2498 if ( !(peer_offered & PEER_OFFERED_CHUNKING)
2499 && (lflags.ok || (pipelining_active && !mua_wrapper)))
2501 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
2503 if (count < 0) goto SEND_FAILED;
2504 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
2505 host, count, ob->address_retry_include_sender, lflags.pending_MAIL,
2506 lflags.ok ? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
2508 case 3: lflags.ok = TRUE; /* 2xx & 5xx => OK & progress made */
2509 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2512 case 1: lflags.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2513 if (!lflags.lmtp) completed_address = TRUE; /* can't tell about progress yet */
2514 case 0: break; /* No 2xx or 5xx, but no probs */
2516 case -1: goto END_OFF; /* Timeout on RCPT */
2517 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2519 pipelining_active = FALSE;
2520 data_command = string_copy(big_buffer); /* Save for later error message */
2523 /* If there were no good recipients (but otherwise there have been no
2524 problems), just set ok TRUE, since we have handled address-specific errors
2525 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
2526 for handling the SMTP dot-handling protocol, flagging to apply to headers as
2527 well as body. Set the appropriate timeout value to be used for each chunk.
2528 (Haven't been able to make it work using select() for writing yet.) */
2530 if (!(peer_offered & PEER_OFFERED_CHUNKING) && !lflags.ok)
2532 /* Save the first address of the next batch. */
2539 transport_ctx tctx = {
2542 US".", US"..", /* Escaping strings */
2543 topt_use_crlf | topt_escape_headers
2544 | (tblock->body_only ? topt_no_headers : 0)
2545 | (tblock->headers_only ? topt_no_body : 0)
2546 | (tblock->return_path_add ? topt_add_return_path : 0)
2547 | (tblock->delivery_date_add ? topt_add_delivery_date : 0)
2548 | (tblock->envelope_to_add ? topt_add_envelope_to : 0)
2551 /* If using CHUNKING we need a callback from the generic transport
2552 support to us, for the sending of BDAT smtp commands and the reaping
2553 of responses. The callback needs a whole bunch of state so set up
2554 a transport-context structure to be passed around. */
2556 if (peer_offered & PEER_OFFERED_CHUNKING)
2558 tctx.check_string = tctx.escape_string = NULL;
2559 tctx.options |= topt_use_bdat;
2560 tctx.chunk_cb = smtp_chunk_cmd_callback;
2561 tctx.inblock = &inblock;
2562 tctx.outblock = &outblock;
2564 tctx.first_addr = first_addr;
2565 tctx.sync_addr = &sync_addr;
2566 tctx.pending_MAIL = lflags.pending_MAIL;
2567 tctx.pending_BDAT = FALSE;
2568 tctx.good_RCPT = lflags.ok;
2569 tctx.completed_address = &completed_address;
2571 tctx.buffer = buffer;
2574 tctx.options |= topt_end_dot;
2576 /* Save the first address of the next batch. */
2579 /* Responses from CHUNKING commands go in buffer. Otherwise,
2580 there has not been a response. */
2584 sigalrm_seen = FALSE;
2585 transport_write_timeout = ob->data_timeout;
2586 smtp_command = US"sending data block"; /* For error messages */
2587 DEBUG(D_transport|D_v)
2588 if (peer_offered & PEER_OFFERED_CHUNKING)
2589 debug_printf(" will write message using CHUNKING\n");
2591 debug_printf(" SMTP>> writing message and terminating \".\"\n");
2592 transport_count = 0;
2594 #ifndef DISABLE_DKIM
2595 lflags.ok = dkim_transport_write_message(inblock.sock, &tctx, &ob->dkim);
2597 lflags.ok = transport_write_message(inblock.sock, &tctx, 0);
2600 /* transport_write_message() uses write() because it is called from other
2601 places to write to non-sockets. This means that under some OS (e.g. Solaris)
2602 it can exit with "Broken pipe" as its error. This really means that the
2603 socket got closed at the far end. */
2605 transport_write_timeout = 0; /* for subsequent transports */
2607 /* Failure can either be some kind of I/O disaster (including timeout),
2608 or the failure of a transport filter or the expansion of added headers.
2609 Or, when CHUNKING, it can be a protocol-detected failure. */
2612 goto RESPONSE_FAILED;
2614 /* We used to send the terminating "." explicitly here, but because of
2615 buffering effects at both ends of TCP/IP connections, you don't gain
2616 anything by keeping it separate, so it might as well go in the final
2617 data buffer for efficiency. This is now done by setting the topt_end_dot
2620 smtp_command = US"end of data";
2622 if (peer_offered & PEER_OFFERED_CHUNKING && tctx.cmd_count > 1)
2624 /* Reap any outstanding MAIL & RCPT commands, but not a DATA-go-ahead */
2625 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
2626 host, tctx.cmd_count-1, ob->address_retry_include_sender,
2627 lflags.pending_MAIL, 0,
2628 &inblock, ob->command_timeout, buffer, sizeof(buffer)))
2630 case 3: lflags.ok = TRUE; /* 2xx & 5xx => OK & progress made */
2631 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2634 case 1: lflags.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2635 if (!lflags.lmtp) completed_address = TRUE; /* can't tell about progress yet */
2636 case 0: break; /* No 2xx or 5xx, but no probs */
2638 case -1: goto END_OFF; /* Timeout on RCPT */
2639 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2643 #ifndef DISABLE_PRDR
2644 /* For PRDR we optionally get a partial-responses warning
2645 * followed by the individual responses, before going on with
2646 * the overall response. If we don't get the warning then deal
2647 * with per non-PRDR. */
2648 if(lflags.prdr_active)
2650 lflags.ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '3',
2652 if (!lflags.ok && errno == 0) switch(buffer[0])
2654 case '2': lflags.prdr_active = FALSE;
2657 case '4': errno = ERRNO_DATA4XX;
2658 addrlist->more_errno |=
2659 ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2666 /* For non-PRDR SMTP, we now read a single response that applies to the
2667 whole message. If it is OK, then all the addresses have been delivered. */
2671 lflags.ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2673 if (!lflags.ok && errno == 0 && buffer[0] == '4')
2675 errno = ERRNO_DATA4XX;
2676 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2680 /* For LMTP, we get back a response for every RCPT command that we sent;
2681 some may be accepted and some rejected. For those that get a response, their
2682 status is fixed; any that are accepted have been handed over, even if later
2683 responses crash - at least, that's how I read RFC 2033.
2685 If all went well, mark the recipient addresses as completed, record which
2686 host/IPaddress they were delivered to, and cut out RSET when sending another
2687 message down the same channel. Write the completed addresses to the journal
2688 now so that they are recorded in case there is a crash of hardware or
2689 software before the spool gets updated. Also record the final SMTP
2690 confirmation if needed (for SMTP only). */
2695 int delivery_time = (int)(time(NULL) - start_delivery_time);
2697 uschar *conf = NULL;
2699 lflags.send_rset = FALSE;
2700 pipelining_active = FALSE;
2702 /* Set up confirmation if needed - applies only to SMTP */
2705 #ifdef DISABLE_EVENT
2706 LOGGING(smtp_confirmation) &&
2711 const uschar *s = string_printing(buffer);
2712 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
2713 conf = (s == buffer)? (uschar *)string_copy(s) : US s;
2716 /* Process all transported addresses - for LMTP or PRDR, read a status for
2719 for (addr = addrlist; addr != first_addr; addr = addr->next)
2721 if (addr->transport_return != PENDING_OK) continue;
2723 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
2724 remaining addresses. Otherwise, it's a return code for just the one
2725 address. For temporary errors, add a retry item for the address so that
2726 it doesn't get tried again too soon. */
2728 #ifndef DISABLE_PRDR
2729 if (lflags.lmtp || lflags.prdr_active)
2734 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2737 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
2738 addr->message = string_sprintf(
2739 #ifndef DISABLE_PRDR
2740 "%s error after %s: %s", lflags.prdr_active ? "PRDR":"LMTP",
2742 "LMTP error after %s: %s",
2744 data_command, string_printing(buffer));
2745 setflag(addr, af_pass_message); /* Allow message to go to user */
2746 if (buffer[0] == '5')
2747 addr->transport_return = FAIL;
2750 errno = ERRNO_DATA4XX;
2751 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2752 addr->transport_return = DEFER;
2753 #ifndef DISABLE_PRDR
2754 if (!lflags.prdr_active)
2756 retry_add_item(addr, addr->address_retry_key, 0);
2760 completed_address = TRUE; /* NOW we can set this flag */
2761 if (LOGGING(smtp_confirmation))
2763 const uschar *s = string_printing(buffer);
2764 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
2765 conf = (s == buffer)? (uschar *)string_copy(s) : US s;
2769 /* SMTP, or success return from LMTP for this address. Pass back the
2770 actual host that was used. */
2772 addr->transport_return = OK;
2773 addr->more_errno = delivery_time;
2774 addr->host_used = host;
2775 addr->special_action = flag;
2776 addr->message = conf;
2777 #ifndef DISABLE_PRDR
2778 if (lflags.prdr_active) addr->flags |= af_prdr_used;
2780 if (peer_offered & PEER_OFFERED_CHUNKING) addr->flags |= af_chunking_used;
2783 #ifndef DISABLE_PRDR
2784 if (!lflags.prdr_active)
2787 /* Update the journal. For homonymic addresses, use the base address plus
2788 the transport name. See lots of comments in deliver.c about the reasons
2789 for the complications when homonyms are involved. Just carry on after
2790 write error, as it may prove possible to update the spool file later. */
2792 if (testflag(addr, af_homonym))
2793 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2795 sprintf(CS buffer, "%.500s\n", addr->unique);
2797 DEBUG(D_deliver) debug_printf("journalling %s\n", buffer);
2798 len = Ustrlen(CS buffer);
2799 if (write(journal_fd, buffer, len) != len)
2800 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2801 "%s: %s", buffer, strerror(errno));
2805 #ifndef DISABLE_PRDR
2806 if (lflags.prdr_active)
2808 /* PRDR - get the final, overall response. For any non-success
2809 upgrade all the address statuses. */
2810 lflags.ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2814 if(errno == 0 && buffer[0] == '4')
2816 errno = ERRNO_DATA4XX;
2817 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2819 for (addr = addrlist; addr != first_addr; addr = addr->next)
2820 if (buffer[0] == '5' || addr->transport_return == OK)
2821 addr->transport_return = PENDING_OK; /* allow set_errno action */
2822 goto RESPONSE_FAILED;
2825 /* Update the journal, or setup retry. */
2826 for (addr = addrlist; addr != first_addr; addr = addr->next)
2827 if (addr->transport_return == OK)
2829 if (testflag(addr, af_homonym))
2830 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2832 sprintf(CS buffer, "%.500s\n", addr->unique);
2834 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s\n", buffer);
2835 len = Ustrlen(CS buffer);
2836 if (write(journal_fd, buffer, len) != len)
2837 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2838 "%s: %s", buffer, strerror(errno));
2840 else if (addr->transport_return == DEFER)
2841 retry_add_item(addr, addr->address_retry_key, -2);
2845 /* Ensure the journal file is pushed out to disk. */
2847 if (EXIMfsync(journal_fd) < 0)
2848 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
2854 /* Handle general (not specific to one address) failures here. The value of ok
2855 is used to skip over this code on the falling through case. A timeout causes a
2856 deferral. Other errors may defer or fail according to the response code, and
2857 may set up a special errno value, e.g. after connection chopped, which is
2858 assumed if errno == 0 and there is no text in the buffer. If control reaches
2859 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
2860 the problem is not related to this specific message. */
2865 uschar * set_message;
2871 lflags.send_quit = check_response(host, &save_errno, addrlist->more_errno,
2872 buffer, &code, &message, &pass_message);
2880 message = US string_sprintf("send() to %s [%s] failed: %s",
2881 host->name, host->address, strerror(save_errno));
2882 lflags.send_quit = FALSE;
2886 /* This label is jumped to directly when a TLS negotiation has failed,
2887 or was not done for a host for which it is required. Values will be set
2888 in message and save_errno, and setting_up will always be true. Treat as
2889 a temporary error. */
2896 /* If the failure happened while setting up the call, see if the failure was
2897 a 5xx response (this will either be on connection, or following HELO - a 5xx
2898 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
2899 never going to accept them. For other errors during setting up (timeouts or
2900 whatever), defer all addresses, and yield DEFER, so that the host is not
2901 tried again for a while. */
2904 lflags.ok = FALSE; /* For when reached by GOTO */
2905 set_message = message;
2907 if (lflags.setting_up)
2911 yield = set_rc = DEFER;
2913 /* We want to handle timeouts after MAIL or "." and loss of connection after
2914 "." specially. They can indicate a problem with the sender address or with
2915 the contents of the message rather than a real error on the connection. These
2916 cases are treated in the same way as a 4xx response. This next bit of code
2917 does the classification. */
2926 case ERRNO_UTF8_FWD:
2933 message_error = TRUE;
2937 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
2938 Ustrncmp(smtp_command,"end ",4) == 0;
2941 case ERRNO_SMTPCLOSED:
2942 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
2946 message_error = FALSE;
2950 /* Handle the cases that are treated as message errors. These are:
2952 (a) negative response or timeout after MAIL
2953 (b) negative response after DATA
2954 (c) negative response or timeout or dropped connection after "."
2955 (d) utf8 support required and not offered
2957 It won't be a negative response or timeout after RCPT, as that is dealt
2958 with separately above. The action in all cases is to set an appropriate
2959 error code for all the addresses, but to leave yield set to OK because the
2960 host itself has not failed. Of course, it might in practice have failed
2961 when we've had a timeout, but if so, we'll discover that at the next
2962 delivery attempt. For a temporary error, set the message_defer flag, and
2963 write to the logs for information if this is not the last host. The error
2964 for the last host will be logged as part of the address's log line. */
2968 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
2970 /* If there's an errno, the message contains just the identity of
2975 else /* Anything other than 5 is treated as temporary */
2979 message = US string_sprintf("%s: %s", message, strerror(save_errno));
2980 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
2981 msglog_line(host, message);
2982 *message_defer = TRUE;
2986 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
2987 ".", or some other transportation error. We defer all addresses and yield
2988 DEFER, except for the case of failed add_headers expansion, or a transport
2989 filter failure, when the yield should be ERROR, to stop it trying other
2995 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
2996 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
3000 set_errno(addrlist, save_errno, set_message, set_rc, pass_message, host
3001 #ifdef EXPERIMENTAL_DSN_INFO
3002 , smtp_greeting, helo_response
3008 /* If all has gone well, send_quit will be set TRUE, implying we can end the
3009 SMTP session tidily. However, if there were too many addresses to send in one
3010 message (indicated by first_addr being non-NULL) we want to carry on with the
3011 rest of them. Also, it is desirable to send more than one message down the SMTP
3012 connection if there are several waiting, provided we haven't already sent so
3013 many as to hit the configured limit. The function transport_check_waiting looks
3014 for a waiting message and returns its id. Then transport_pass_socket tries to
3015 set up a continued delivery by passing the socket on to another process. The
3016 variable send_rset is FALSE if a message has just been successfully transfered.
3018 If we are already sending down a continued channel, there may be further
3019 addresses not yet delivered that are aimed at the same host, but which have not
3020 been passed in this run of the transport. In this case, continue_more will be
3021 true, and all we should do is send RSET if necessary, and return, leaving the
3024 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
3025 do not want to continue with other messages down the same channel, because that
3026 can lead to looping between two or more messages, all with the same,
3027 temporarily failing address(es). [The retry information isn't updated yet, so
3028 new processes keep on trying.] We probably also don't want to try more of this
3029 message's addresses either.
3031 If we have started a TLS session, we have to end it before passing the
3032 connection to a new process. However, not all servers can handle this (Exim
3033 can), so we do not pass such a connection on if the host matches
3034 hosts_nopass_tls. */
3037 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
3038 "yield=%d first_address is %sNULL\n", lflags.ok, lflags.send_quit,
3039 lflags.send_rset, continue_more, yield, first_addr ? "not " : "");
3041 if (completed_address && lflags.ok && lflags.send_quit)
3044 smtp_compare_t t_compare;
3046 t_compare.tblock = tblock;
3047 t_compare.current_sender_address = sender_address;
3049 if ( first_addr != NULL
3051 || ( ( tls_out.active < 0
3052 || verify_check_given_host(&ob->hosts_nopass_tls, host) != OK
3055 transport_check_waiting(tblock->name, host->name,
3056 tblock->connection_max_messages, new_message_id, &more,
3057 (oicf)smtp_are_same_identities, (void*)&t_compare)
3063 if (lflags.send_rset)
3065 if (! (lflags.ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
3067 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
3068 host->address, strerror(save_errno));
3069 lflags.send_quit = FALSE;
3071 else if (! (lflags.ok = smtp_read_response(&inblock, buffer,
3072 sizeof(buffer), '2', ob->command_timeout)))
3075 lflags.send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
3077 if (!lflags.send_quit)
3079 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
3080 host->name, host->address, msg);
3085 /* Either RSET was not needed, or it succeeded */
3089 if (first_addr != NULL) /* More addresses still to be sent */
3090 { /* in this run of the transport */
3091 continue_sequence++; /* Causes * in logging */
3094 if (continue_more) return yield; /* More addresses for another run */
3096 /* Pass the socket to a new Exim process. Before doing so, we must shut
3097 down TLS. Not all MTAs allow for the continuation of the SMTP session
3098 when TLS is shut down. We test for this by sending a new EHLO. If we
3099 don't get a good response, we don't attempt to pass the socket on. */
3102 if (tls_out.active >= 0)
3104 tls_close(FALSE, TRUE);
3105 smtp_peer_options = smtp_peer_options_wrap;
3109 lflags.ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
3110 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
3111 ob->command_timeout);
3115 /* If the socket is successfully passed, we musn't send QUIT (or
3116 indeed anything!) from here. */
3118 /*XXX DSN_INFO: assume likely to do new HELO; but for greet we'll want to
3119 propagate it from the initial
3121 if (lflags.ok && transport_pass_socket(tblock->name, host->name,
3122 host->address, new_message_id, inblock.sock))
3123 lflags.send_quit = FALSE;
3126 /* If RSET failed and there are addresses left, they get deferred. */
3128 else set_errno(first_addr, errno, msg, DEFER, FALSE, host
3129 #ifdef EXPERIMENTAL_DSN_INFO
3130 , smtp_greeting, helo_response
3136 /* End off tidily with QUIT unless the connection has died or the socket has
3137 been passed to another process. There has been discussion on the net about what
3138 to do after sending QUIT. The wording of the RFC suggests that it is necessary
3139 to wait for a response, but on the other hand, there isn't anything one can do
3140 with an error response, other than log it. Exim used to do that. However,
3141 further discussion suggested that it is positively advantageous not to wait for
3142 the response, but to close the session immediately. This is supposed to move
3143 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
3144 load from the server. (Hosts that are both servers and clients may not see much
3145 difference, of course.) Further discussion indicated that this was safe to do
3146 on Unix systems which have decent implementations of TCP/IP that leave the
3147 connection around for a while (TIME_WAIT) after the application has gone away.
3148 This enables the response sent by the server to be properly ACKed rather than
3149 timed out, as can happen on broken TCP/IP implementations on other OS.
3151 This change is being made on 31-Jul-98. After over a year of trouble-free
3152 operation, the old commented-out code was removed on 17-Sep-99. */
3155 if (lflags.send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
3160 tls_close(FALSE, TRUE);
3163 /* Close the socket, and return the appropriate value, first setting
3164 works because the NULL setting is passed back to the calling process, and
3165 remote_max_parallel is forced to 1 when delivering over an existing connection,
3167 If all went well and continue_more is set, we shouldn't actually get here if
3168 there are further addresses, as the return above will be taken. However,
3169 writing RSET might have failed, or there may be other addresses whose hosts are
3170 specified in the transports, and therefore not visible at top level, in which
3171 case continue_more won't get set. */
3173 HDEBUG(D_transport|D_acl|D_v) debug_printf(" SMTP(close)>>\n");
3174 if (lflags.send_quit)
3176 shutdown(outblock.sock, SHUT_WR);
3177 if (fcntl(inblock.sock, F_SETFL, O_NONBLOCK) == 0)
3178 for (rc = 16; read(inblock.sock, inbuffer, sizeof(inbuffer)) > 0 && rc > 0;)
3179 rc--; /* drain socket */
3181 (void)close(inblock.sock);
3183 #ifndef DISABLE_EVENT
3184 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
3187 continue_transport = NULL;
3188 continue_hostname = NULL;
3195 /*************************************************
3196 * Closedown entry point *
3197 *************************************************/
3199 /* This function is called when exim is passed an open smtp channel
3200 from another incarnation, but the message which it has been asked
3201 to deliver no longer exists. The channel is on stdin.
3203 We might do fancy things like looking for another message to send down
3204 the channel, but if the one we sought has gone, it has probably been
3205 delivered by some other process that itself will seek further messages,
3206 so just close down our connection.
3208 Argument: pointer to the transport instance block
3213 smtp_transport_closedown(transport_instance *tblock)
3215 smtp_transport_options_block *ob =
3216 (smtp_transport_options_block *)(tblock->options_block);
3217 smtp_inblock inblock;
3218 smtp_outblock outblock;
3220 uschar inbuffer[4096];
3221 uschar outbuffer[16];
3223 inblock.sock = fileno(stdin);
3224 inblock.buffer = inbuffer;
3225 inblock.buffersize = sizeof(inbuffer);
3226 inblock.ptr = inbuffer;
3227 inblock.ptrend = inbuffer;
3229 outblock.sock = inblock.sock;
3230 outblock.buffersize = sizeof(outbuffer);
3231 outblock.buffer = outbuffer;
3232 outblock.ptr = outbuffer;
3233 outblock.cmd_count = 0;
3234 outblock.authenticating = FALSE;
3236 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
3237 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
3238 ob->command_timeout);
3239 (void)close(inblock.sock);
3244 /*************************************************
3245 * Prepare addresses for delivery *
3246 *************************************************/
3248 /* This function is called to flush out error settings from previous delivery
3249 attempts to other hosts. It also records whether we got here via an MX record
3250 or not in the more_errno field of the address. We are interested only in
3251 addresses that are still marked DEFER - others may have got delivered to a
3252 previously considered IP address. Set their status to PENDING_DEFER to indicate
3253 which ones are relevant this time.
3256 addrlist the list of addresses
3257 host the host we are delivering to
3259 Returns: the first address for this delivery
3262 static address_item *
3263 prepare_addresses(address_item *addrlist, host_item *host)
3265 address_item *first_addr = NULL;
3267 for (addr = addrlist; addr; addr = addr->next)
3268 if (addr->transport_return == DEFER)
3270 if (!first_addr) first_addr = addr;
3271 addr->transport_return = PENDING_DEFER;
3272 addr->basic_errno = 0;
3273 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
3274 addr->message = NULL;
3276 addr->cipher = NULL;
3277 addr->ourcert = NULL;
3278 addr->peercert = NULL;
3279 addr->peerdn = NULL;
3280 addr->ocsp = OCSP_NOT_REQ;
3282 #ifdef EXPERIMENTAL_DSN_INFO
3283 addr->smtp_greeting = NULL;
3284 addr->helo_response = NULL;
3292 /*************************************************
3293 * Main entry point *
3294 *************************************************/
3296 /* See local README for interface details. As this is a remote transport, it is
3297 given a chain of addresses to be delivered in one connection, if possible. It
3298 always returns TRUE, indicating that each address has its own independent
3299 status set, except if there is a setting up problem, in which case it returns
3303 smtp_transport_entry(
3304 transport_instance *tblock, /* data for this instantiation */
3305 address_item *addrlist) /* addresses we are working on */
3309 int hosts_defer = 0;
3311 int hosts_looked_up = 0;
3312 int hosts_retry = 0;
3313 int hosts_serial = 0;
3314 int hosts_total = 0;
3315 int total_hosts_tried = 0;
3317 BOOL expired = TRUE;
3318 uschar *expanded_hosts = NULL;
3320 uschar *tid = string_sprintf("%s transport", tblock->name);
3321 smtp_transport_options_block *ob =
3322 (smtp_transport_options_block *)(tblock->options_block);
3323 host_item *hostlist = addrlist->host_list;
3324 host_item *host = NULL;
3328 debug_printf("%s transport entered\n", tblock->name);
3329 for (addr = addrlist; addr; addr = addr->next)
3330 debug_printf(" %s\n", addr->address);
3333 debug_printf("hostlist:\n");
3334 for (host = hostlist; host; host = host->next)
3335 debug_printf(" %s:%d\n", host->name, host->port);
3337 if (continue_hostname) debug_printf("already connected to %s [%s]\n",
3338 continue_hostname, continue_host_address);
3341 /* Set the flag requesting that these hosts be added to the waiting
3342 database if the delivery fails temporarily or if we are running with
3343 queue_smtp or a 2-stage queue run. This gets unset for certain
3344 kinds of error, typically those that are specific to the message. */
3346 update_waiting = TRUE;
3348 /* If a host list is not defined for the addresses - they must all have the
3349 same one in order to be passed to a single transport - or if the transport has
3350 a host list with hosts_override set, use the host list supplied with the
3351 transport. It is an error for this not to exist. */
3353 if (!hostlist || (ob->hosts_override && ob->hosts))
3357 addrlist->message = string_sprintf("%s transport called with no hosts set",
3359 addrlist->transport_return = PANIC;
3360 return FALSE; /* Only top address has status */
3363 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
3366 /* If the transport's host list contains no '$' characters, and we are not
3367 randomizing, it is fixed and therefore a chain of hosts can be built once
3368 and for all, and remembered for subsequent use by other calls to this
3369 transport. If, on the other hand, the host list does contain '$', or we are
3370 randomizing its order, we have to rebuild it each time. In the fixed case,
3371 as the hosts string will never be used again, it doesn't matter that we
3372 replace all the : characters with zeros. */
3376 uschar *s = ob->hosts;
3378 if (Ustrchr(s, '$') != NULL)
3380 if (!(expanded_hosts = expand_string(s)))
3382 addrlist->message = string_sprintf("failed to expand list of hosts "
3383 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
3384 addrlist->transport_return = search_find_defer ? DEFER : PANIC;
3385 return FALSE; /* Only top address has status */
3387 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
3388 "\"%s\"\n", s, expanded_hosts);
3392 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
3394 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
3396 /* Check that the expansion yielded something useful. */
3400 string_sprintf("%s transport has empty hosts setting", tblock->name);
3401 addrlist->transport_return = PANIC;
3402 return FALSE; /* Only top address has status */
3405 /* If there was no expansion of hosts, save the host list for
3408 if (!expanded_hosts) ob->hostlist = hostlist;
3411 /* This is not the first time this transport has been run in this delivery;
3412 the host list was built previously. */
3415 hostlist = ob->hostlist;
3418 /* The host list was supplied with the address. If hosts_randomize is set, we
3419 must sort it into a random order if it did not come from MX records and has not
3420 already been randomized (but don't bother if continuing down an existing
3423 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continue_hostname)
3425 host_item *newlist = NULL;
3428 host_item *h = hostlist;
3429 hostlist = hostlist->next;
3431 h->sort_key = random_number(100);
3438 else if (h->sort_key < newlist->sort_key)
3445 host_item *hh = newlist;
3448 if (h->sort_key < hh->next->sort_key) break;
3456 hostlist = addrlist->host_list = newlist;
3459 /* Sort out the default port. */
3461 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
3463 /* For each host-plus-IP-address on the list:
3465 . If this is a continued delivery and the host isn't the one with the
3466 current connection, skip.
3468 . If the status is unusable (i.e. previously failed or retry checked), skip.
3470 . If no IP address set, get the address, either by turning the name into
3471 an address, calling gethostbyname if gethostbyname is on, or by calling
3472 the DNS. The DNS may yield multiple addresses, in which case insert the
3473 extra ones into the list.
3475 . Get the retry data if not previously obtained for this address and set the
3476 field which remembers the state of this address. Skip if the retry time is
3477 not reached. If not, remember whether retry data was found. The retry string
3478 contains both the name and the IP address.
3480 . Scan the list of addresses and mark those whose status is DEFER as
3481 PENDING_DEFER. These are the only ones that will be processed in this cycle
3484 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
3485 Some addresses may be successfully delivered, others may fail, and yet
3486 others may get temporary errors and so get marked DEFER.
3488 . The return from the delivery attempt is OK if a connection was made and a
3489 valid SMTP dialogue was completed. Otherwise it is DEFER.
3491 . If OK, add a "remove" retry item for this host/IPaddress, if any.
3493 . If fail to connect, or other defer state, add a retry item.
3495 . If there are any addresses whose status is still DEFER, carry on to the
3496 next host/IPaddress, unless we have tried the number of hosts given
3497 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
3498 there is some fancy logic for hosts_max_try that means its limit can be
3499 overstepped in some circumstances.
3501 If we get to the end of the list, all hosts have deferred at least one address,
3502 or not reached their retry times. If delay_after_cutoff is unset, it requests a
3503 delivery attempt to those hosts whose last try was before the arrival time of
3504 the current message. To cope with this, we have to go round the loop a second
3505 time. After that, set the status and error data for any addresses that haven't
3506 had it set already. */
3508 for (cutoff_retry = 0;
3509 expired && cutoff_retry < (ob->delay_after_cutoff ? 1 : 2);
3512 host_item *nexthost = NULL;
3513 int unexpired_hosts_tried = 0;
3515 for (host = hostlist;
3517 && unexpired_hosts_tried < ob->hosts_max_try
3518 && total_hosts_tried < ob->hosts_max_try_hardlimit;
3524 BOOL host_is_expired = FALSE;
3525 BOOL message_defer = FALSE;
3526 BOOL some_deferred = FALSE;
3527 address_item *first_addr = NULL;
3528 uschar *interface = NULL;
3529 uschar *retry_host_key = NULL;
3530 uschar *retry_message_key = NULL;
3531 uschar *serialize_key = NULL;
3533 /* Default next host is next host. :-) But this can vary if the
3534 hosts_max_try limit is hit (see below). It may also be reset if a host
3535 address is looked up here (in case the host was multihomed). */
3537 nexthost = host->next;
3539 /* If the address hasn't yet been obtained from the host name, look it up
3540 now, unless the host is already marked as unusable. If it is marked as
3541 unusable, it means that the router was unable to find its IP address (in
3542 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
3543 the lookup failed last time. We don't get this far if *all* MX records
3544 point to non-existent hosts; that is treated as a hard error.
3546 We can just skip this host entirely. When the hosts came from the router,
3547 the address will timeout based on the other host(s); when the address is
3548 looked up below, there is an explicit retry record added.
3550 Note that we mustn't skip unusable hosts if the address is not unset; they
3551 may be needed as expired hosts on the 2nd time round the cutoff loop. */
3555 int new_port, flags;
3558 if (host->status >= hstatus_unusable)
3560 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
3565 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
3567 /* The host name is permitted to have an attached port. Find it, and
3568 strip it from the name. Just remember it for now. */
3570 new_port = host_item_get_port(host);
3572 /* Count hosts looked up */
3576 /* Find by name if so configured, or if it's an IP address. We don't
3577 just copy the IP address, because we need the test-for-local to happen. */
3579 flags = HOST_FIND_BY_A;
3580 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
3581 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
3583 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
3584 rc = host_find_byname(host, NULL, flags, NULL, TRUE);
3586 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
3587 &ob->dnssec, /* domains for request/require */
3590 /* Update the host (and any additional blocks, resulting from
3591 multihoming) with a host-specific port, if any. */
3593 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
3595 /* Failure to find the host at this time (usually DNS temporary failure)
3596 is really a kind of routing failure rather than a transport failure.
3597 Therefore we add a retry item of the routing kind, not to stop us trying
3598 to look this name up here again, but to ensure the address gets timed
3599 out if the failures go on long enough. A complete failure at this point
3600 commonly points to a configuration error, but the best action is still
3601 to carry on for the next host. */
3603 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
3605 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
3607 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
3608 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
3609 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
3610 host->status = hstatus_unusable;
3612 for (addr = addrlist; addr; addr = addr->next)
3614 if (addr->transport_return != DEFER) continue;
3615 addr->basic_errno = ERRNO_UNKNOWNHOST;
3617 string_sprintf("failed to lookup IP address for %s", host->name);
3622 /* If the host is actually the local host, we may have a problem, or
3623 there may be some cunning configuration going on. In the problem case,
3624 log things and give up. The default transport status is already DEFER. */
3626 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
3628 for (addr = addrlist; addr; addr = addr->next)
3630 addr->basic_errno = 0;
3631 addr->message = string_sprintf("%s transport found host %s to be "
3632 "local", tblock->name, host->name);
3636 } /* End of block for IP address lookup */
3638 /* If this is a continued delivery, we are interested only in the host
3639 which matches the name of the existing open channel. The check is put
3640 here after the local host lookup, in case the name gets expanded as a
3641 result of the lookup. Set expired FALSE, to save the outer loop executing
3644 if ( continue_hostname
3645 && ( Ustrcmp(continue_hostname, host->name) != 0
3646 || Ustrcmp(continue_host_address, host->address) != 0
3650 continue; /* With next host */
3653 /* Reset the default next host in case a multihomed host whose addresses
3654 are not looked up till just above added to the host list. */
3656 nexthost = host->next;
3658 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
3659 domain is in queue_smtp_domains, we don't actually want to attempt any
3660 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
3661 there is a lookup defer in queue_smtp_domains, proceed as if the domain
3662 were not in it. We don't want to hold up all SMTP deliveries! Except when
3663 doing a two-stage queue run, don't do this if forcing. */
3665 if ((!deliver_force || queue_2stage) && (queue_smtp ||
3666 match_isinlist(addrlist->domain,
3667 (const uschar **)&queue_smtp_domains, 0,
3668 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
3671 for (addr = addrlist; addr; addr = addr->next)
3672 if (addr->transport_return == DEFER)
3673 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
3674 continue; /* With next host */
3677 /* Count hosts being considered - purely for an intelligent comment
3678 if none are usable. */
3682 /* Set $host and $host address now in case they are needed for the
3683 interface expansion or the serialize_hosts check; they remain set if an
3684 actual delivery happens. */
3686 deliver_host = host->name;
3687 deliver_host_address = host->address;
3688 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
3689 : host->dnssec == DS_NO ? US"no"
3692 /* Set up a string for adding to the retry key if the port number is not
3693 the standard SMTP port. A host may have its own port setting that overrides
3696 pistring = string_sprintf(":%d", host->port == PORT_NONE
3697 ? port : host->port);
3698 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
3700 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
3701 string is set, even if constant (as different transports can have different
3702 constant settings), we must add it to the key that is used for retries,
3703 because connections to the same host from a different interface should be
3704 treated separately. */
3706 host_af = Ustrchr(host->address, ':') == NULL ? AF_INET : AF_INET6;
3707 if ((rs = ob->interface) && *rs)
3709 if (!smtp_get_interface(rs, host_af, addrlist, &interface, tid))
3711 pistring = string_sprintf("%s/%s", pistring, interface);
3714 /* The first time round the outer loop, check the status of the host by
3715 inspecting the retry data. The second time round, we are interested only
3716 in expired hosts that haven't been tried since this message arrived. */
3718 if (cutoff_retry == 0)
3721 /* Ensure the status of the address is set by checking retry data if
3722 necessary. There may be host-specific retry data (applicable to all
3723 messages) and also data for retries of a specific message at this host.
3724 If either of these retry records are actually read, the keys used are
3725 returned to save recomputing them later. */
3727 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3728 US"retry_include_ip_address", ob->retry_include_ip_address,
3729 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3730 continue; /* with next host */
3732 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
3733 incl_ip, &retry_host_key, &retry_message_key);
3735 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
3736 (host->address == NULL)? US"" : host->address, pistring,
3737 (host->status == hstatus_usable)? "usable" :
3738 (host->status == hstatus_unusable)? "unusable" :
3739 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
3741 /* Skip this address if not usable at this time, noting if it wasn't
3742 actually expired, both locally and in the address. */
3744 switch (host->status)
3746 case hstatus_unusable:
3748 setflag(addrlist, af_retry_skipped);
3751 case hstatus_unusable_expired:
3754 case hwhy_retry: hosts_retry++; break;
3755 case hwhy_failed: hosts_fail++; break;
3756 case hwhy_deferred: hosts_defer++; break;
3759 /* If there was a retry message key, implying that previously there
3760 was a message-specific defer, we don't want to update the list of
3761 messages waiting for these hosts. */
3763 if (retry_message_key) update_waiting = FALSE;
3764 continue; /* With the next host or IP address */
3768 /* Second time round the loop: if the address is set but expired, and
3769 the message is newer than the last try, let it through. */
3774 || host->status != hstatus_unusable_expired
3775 || host->last_try > received_time)
3777 DEBUG(D_transport) debug_printf("trying expired host %s [%s]%s\n",
3778 host->name, host->address, pistring);
3779 host_is_expired = TRUE;
3782 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
3783 it remains TRUE only if all hosts are expired and none are actually tried.
3788 /* If this host is listed as one to which access must be serialized,
3789 see if another Exim process has a connection to it, and if so, skip
3790 this host. If not, update the database to record our connection to it
3791 and remember this for later deletion. Do not do any of this if we are
3792 sending the message down a pre-existing connection. */
3794 if ( !continue_hostname
3795 && verify_check_given_host(&ob->serialize_hosts, host) == OK)
3797 serialize_key = string_sprintf("host-serialize-%s", host->name);
3798 if (!enq_start(serialize_key, 1))
3801 debug_printf("skipping host %s because another Exim process "
3802 "is connected to it\n", host->name);
3808 /* OK, we have an IP address that is not waiting for its retry time to
3809 arrive (it might be expired) OR (second time round the loop) we have an
3810 expired host that hasn't been tried since the message arrived. Have a go
3811 at delivering the message to it. First prepare the addresses by flushing
3812 out the result of previous attempts, and finding the first address that
3813 is still to be delivered. */
3815 first_addr = prepare_addresses(addrlist, host);
3817 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
3818 message_id, host->name, host->address, addrlist->address,
3819 addrlist->next ? ", ..." : "");
3821 set_process_info("delivering %s to %s [%s] (%s%s)",
3822 message_id, host->name, host->address, addrlist->address,
3823 addrlist->next ? ", ..." : "");
3825 /* This is not for real; don't do the delivery. If there are
3826 any remaining hosts, list them. */
3831 set_errno_nohost(addrlist, 0, NULL, OK, FALSE);
3832 for (addr = addrlist; addr; addr = addr->next)
3834 addr->host_used = host;
3835 addr->special_action = '*';
3836 addr->message = US"delivery bypassed by -N option";
3840 debug_printf("*** delivery by %s transport bypassed by -N option\n"
3841 "*** host and remaining hosts:\n", tblock->name);
3842 for (host2 = host; host2; host2 = host2->next)
3843 debug_printf(" %s [%s]\n", host2->name,
3844 host2->address ? host2->address : US"unset");
3849 /* This is for real. If the host is expired, we don't count it for
3850 hosts_max_retry. This ensures that all hosts must expire before an address
3851 is timed out, unless hosts_max_try_hardlimit (which protects against
3852 lunatic DNS configurations) is reached.
3854 If the host is not expired and we are about to hit the hosts_max_retry
3855 limit, check to see if there is a subsequent hosts with a different MX
3856 value. If so, make that the next host, and don't count this one. This is a
3857 heuristic to make sure that different MXs do get tried. With a normal kind
3858 of retry rule, they would get tried anyway when the earlier hosts were
3859 delayed, but if the domain has a "retry every time" type of rule - as is
3860 often used for the the very large ISPs, that won't happen. */
3865 /* Make a copy of the host if it is local to this invocation
3866 of the transport. */
3870 thost = store_get(sizeof(host_item));
3872 thost->name = string_copy(host->name);
3873 thost->address = string_copy(host->address);
3878 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
3882 debug_printf("hosts_max_try limit reached with this host\n");
3883 for (h = host; h; h = h->next) if (h->mx != host->mx)
3886 unexpired_hosts_tried--;
3887 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
3888 "and will be tried\n");
3893 /* Attempt the delivery. */
3895 total_hosts_tried++;
3896 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
3897 &message_defer, FALSE);
3900 OK => connection made, each address contains its result;
3901 message_defer is set for message-specific defers (when all
3902 recipients are marked defer)
3903 DEFER => there was a non-message-specific delivery problem;
3904 ERROR => there was a problem setting up the arguments for a filter,
3905 or there was a problem with expanding added headers
3908 /* If the result is not OK, there was a non-message-specific problem.
3909 If the result is DEFER, we need to write to the logs saying what happened
3910 for this particular host, except in the case of authentication and TLS
3911 failures, where the log has already been written. If all hosts defer a
3912 general message is written at the end. */
3914 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL
3915 && first_addr->basic_errno != ERRNO_TLSFAILURE)
3916 write_logs(first_addr, host);
3918 #ifndef DISABLE_EVENT
3920 deferred_event_raise(first_addr, host);
3923 /* If STARTTLS was accepted, but there was a failure in setting up the
3924 TLS session (usually a certificate screwup), and the host is not in
3925 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
3926 TLS forcibly turned off. We have to start from scratch with a new SMTP
3927 connection. That's why the retry is done from here, not from within
3928 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
3929 session, so the in-clear transmission after those errors, if permitted,
3930 happens inside smtp_deliver().] */
3934 && first_addr->basic_errno == ERRNO_TLSFAILURE
3935 && ob->tls_tempfail_tryclear
3936 && verify_check_given_host(&ob->hosts_require_tls, host) != OK
3939 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
3940 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
3941 first_addr = prepare_addresses(addrlist, host);
3942 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
3943 &message_defer, TRUE);
3944 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
3945 write_logs(first_addr, host);
3946 # ifndef DISABLE_EVENT
3948 deferred_event_raise(first_addr, host);
3951 #endif /*SUPPORT_TLS*/
3954 /* Delivery attempt finished */
3956 rs = rc == OK ? US"OK"
3957 : rc == DEFER ? US"DEFER"
3958 : rc == ERROR ? US"ERROR"
3961 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
3962 message_id, host->name, host->address, addrlist->address,
3963 addrlist->next ? " (& others)" : "", rs);
3965 /* Release serialization if set up */
3967 if (serialize_key) enq_end(serialize_key);
3969 /* If the result is DEFER, or if a host retry record is known to exist, we
3970 need to add an item to the retry chain for updating the retry database
3971 at the end of delivery. We only need to add the item to the top address,
3972 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
3973 for any other delivery attempts using the same address. (It is copied into
3974 the unusable tree at the outer level, so even if different address blocks
3975 contain the same address, it still won't get tried again.) */
3977 if (rc == DEFER || retry_host_key)
3979 int delete_flag = rc != DEFER ? rf_delete : 0;
3980 if (!retry_host_key)
3983 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3984 US"retry_include_ip_address", ob->retry_include_ip_address,
3985 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3986 incl_ip = TRUE; /* error; use most-specific retry record */
3988 retry_host_key = incl_ip
3989 ? string_sprintf("T:%S:%s%s", host->name, host->address, pistring)
3990 : string_sprintf("T:%S%s", host->name, pistring);
3993 /* If a delivery of another message over an existing SMTP connection
3994 yields DEFER, we do NOT set up retry data for the host. This covers the
3995 case when there are delays in routing the addresses in the second message
3996 that are so long that the server times out. This is alleviated by not
3997 routing addresses that previously had routing defers when handling an
3998 existing connection, but even so, this case may occur (e.g. if a
3999 previously happily routed address starts giving routing defers). If the
4000 host is genuinely down, another non-continued message delivery will
4001 notice it soon enough. */
4003 if (delete_flag != 0 || !continue_hostname)
4004 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
4006 /* We may have tried an expired host, if its retry time has come; ensure
4007 the status reflects the expiry for the benefit of any other addresses. */
4011 host->status = host_is_expired
4012 ? hstatus_unusable_expired : hstatus_unusable;
4013 host->why = hwhy_deferred;
4017 /* If message_defer is set (host was OK, but every recipient got deferred
4018 because of some message-specific problem), or if that had happened
4019 previously so that a message retry key exists, add an appropriate item
4020 to the retry chain. Note that if there was a message defer but now there is
4021 a host defer, the message defer record gets deleted. That seems perfectly
4022 reasonable. Also, stop the message from being remembered as waiting
4023 for specific hosts. */
4025 if (message_defer || retry_message_key)
4027 int delete_flag = message_defer ? 0 : rf_delete;
4028 if (!retry_message_key)
4031 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
4032 US"retry_include_ip_address", ob->retry_include_ip_address,
4033 ob->expand_retry_include_ip_address, &incl_ip) != OK)
4034 incl_ip = TRUE; /* error; use most-specific retry record */
4036 retry_message_key = incl_ip
4037 ? string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
4039 : string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
4041 retry_add_item(addrlist, retry_message_key,
4042 rf_message | rf_host | delete_flag);
4043 update_waiting = FALSE;
4046 /* Any return other than DEFER (that is, OK or ERROR) means that the
4047 addresses have got their final statuses filled in for this host. In the OK
4048 case, see if any of them are deferred. */
4051 for (addr = addrlist; addr; addr = addr->next)
4052 if (addr->transport_return == DEFER)
4054 some_deferred = TRUE;
4058 /* If no addresses deferred or the result was ERROR, return. We do this for
4059 ERROR because a failing filter set-up or add_headers expansion is likely to
4060 fail for any host we try. */
4062 if (rc == ERROR || (rc == OK && !some_deferred))
4064 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
4065 return TRUE; /* Each address has its status */
4068 /* If the result was DEFER or some individual addresses deferred, let
4069 the loop run to try other hosts with the deferred addresses, except for the
4070 case when we were trying to deliver down an existing channel and failed.
4071 Don't try any other hosts in this case. */
4073 if (continue_hostname) break;
4075 /* If the whole delivery, or some individual addresses, were deferred and
4076 there are more hosts that could be tried, do not count this host towards
4077 the hosts_max_try limit if the age of the message is greater than the
4078 maximum retry time for this host. This means we may try try all hosts,
4079 ignoring the limit, when messages have been around for some time. This is
4080 important because if we don't try all hosts, the address will never time
4081 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
4083 if ((rc == DEFER || some_deferred) && nexthost)
4086 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
4088 if (retry && retry->rules)
4090 retry_rule *last_rule;
4091 for (last_rule = retry->rules;
4093 last_rule = last_rule->next);
4094 timedout = time(NULL) - received_time > last_rule->timeout;
4096 else timedout = TRUE; /* No rule => timed out */
4100 unexpired_hosts_tried--;
4101 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
4102 "hosts_max_try (message older than host's retry time)\n");
4105 } /* End of loop for trying multiple hosts. */
4107 /* This is the end of the loop that repeats iff expired is TRUE and
4108 ob->delay_after_cutoff is FALSE. The second time round we will
4109 try those hosts that haven't been tried since the message arrived. */
4113 debug_printf("all IP addresses skipped or deferred at least one address\n");
4114 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
4115 debug_printf("retrying IP addresses not tried since message arrived\n");
4120 /* Get here if all IP addresses are skipped or defer at least one address. In
4121 MUA wrapper mode, this will happen only for connection or other non-message-
4122 specific failures. Force the delivery status for all addresses to FAIL. */
4126 for (addr = addrlist; addr; addr = addr->next)
4127 addr->transport_return = FAIL;
4131 /* In the normal, non-wrapper case, add a standard message to each deferred
4132 address if there hasn't been an error, that is, if it hasn't actually been
4133 tried this time. The variable "expired" will be FALSE if any deliveries were
4134 actually tried, or if there was at least one host that was not expired. That
4135 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
4136 a delivery has been tried, an error code will be set, and the failing of the
4137 message is handled by the retry code later.
4139 If queue_smtp is set, or this transport was called to send a subsequent message
4140 down an existing TCP/IP connection, and something caused the host not to be
4141 found, we end up here, but can detect these cases and handle them specially. */
4143 for (addr = addrlist; addr; addr = addr->next)
4145 /* If host is not NULL, it means that we stopped processing the host list
4146 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
4147 means we need to behave as if some hosts were skipped because their retry
4148 time had not come. Specifically, this prevents the address from timing out.
4149 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
4150 hosts were tried. */
4153 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
4156 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
4157 "hosts were tried\n");
4162 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
4163 setflag(addr, af_retry_skipped);
4166 if (queue_smtp) /* no deliveries attempted */
4168 addr->transport_return = DEFER;
4169 addr->basic_errno = 0;
4170 addr->message = US"SMTP delivery explicitly queued";
4173 else if ( addr->transport_return == DEFER
4174 && (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0)
4178 addr->basic_errno = ERRNO_HRETRY;
4179 if (continue_hostname)
4180 addr->message = US"no host found for existing SMTP connection";
4183 setflag(addr, af_pass_message); /* This is not a security risk */
4184 addr->message = string_sprintf(
4185 "all hosts%s have been failing for a long time %s",
4186 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"",
4187 ob->delay_after_cutoff
4188 ? US"(and retry time not reached)"
4189 : US"and were last tried after this message arrived");
4191 /* If we are already using fallback hosts, or there are no fallback hosts
4192 defined, convert the result to FAIL to cause a bounce. */
4194 if (addr->host_list == addr->fallback_hosts || !addr->fallback_hosts)
4195 addr->transport_return = FAIL;
4200 if (hosts_retry == hosts_total)
4201 s = "retry time not reached for any host%s";
4202 else if (hosts_fail == hosts_total)
4203 s = "all host address lookups%s failed permanently";
4204 else if (hosts_defer == hosts_total)
4205 s = "all host address lookups%s failed temporarily";
4206 else if (hosts_serial == hosts_total)
4207 s = "connection limit reached for all hosts%s";
4208 else if (hosts_fail+hosts_defer == hosts_total)
4209 s = "all host address lookups%s failed";
4211 s = "some host address lookups failed and retry time "
4212 "not reached for other hosts or connection limit reached%s";
4214 addr->message = string_sprintf(s,
4215 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"");
4220 /* Update the database which keeps information about which messages are waiting
4221 for which hosts to become available. For some message-specific errors, the
4222 update_waiting flag is turned off because we don't want follow-on deliveries in
4223 those cases. If this transport instance is explicitly limited to one message
4224 per connection then follow-on deliveries are not possible and there's no need
4225 to create/update the per-transport wait-<transport_name> database. */
4227 if (update_waiting && tblock->connection_max_messages != 1)
4228 transport_update_waiting(hostlist, tblock->name);
4232 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
4234 return TRUE; /* Each address has its status */
4239 /* End of transport/smtp.c */