1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2014 */
6 /* See the file NOTICE for conditions of use and distribution. */
12 #define PENDING_DEFER (PENDING + DEFER)
13 #define PENDING_OK (PENDING + OK)
16 /* Options specific to the smtp transport. This transport also supports LMTP
17 over TCP/IP. The options must be in alphabetic order (note that "_" comes
18 before the lower case letters). Some live in the transport_instance block so as
19 to be publicly visible; these are flagged with opt_public. */
21 optionlist smtp_transport_options[] = {
22 { "*expand_multi_domain", opt_stringptr | opt_hidden | opt_public,
23 (void *)offsetof(transport_instance, expand_multi_domain) },
24 { "*expand_retry_include_ip_address", opt_stringptr | opt_hidden,
25 (void *)(offsetof(smtp_transport_options_block, expand_retry_include_ip_address)) },
27 { "address_retry_include_sender", opt_bool,
28 (void *)offsetof(smtp_transport_options_block, address_retry_include_sender) },
29 { "allow_localhost", opt_bool,
30 (void *)offsetof(smtp_transport_options_block, allow_localhost) },
31 { "authenticated_sender", opt_stringptr,
32 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
33 { "authenticated_sender_force", opt_bool,
34 (void *)offsetof(smtp_transport_options_block, authenticated_sender_force) },
35 { "command_timeout", opt_time,
36 (void *)offsetof(smtp_transport_options_block, command_timeout) },
37 { "connect_timeout", opt_time,
38 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
39 { "connection_max_messages", opt_int | opt_public,
40 (void *)offsetof(transport_instance, connection_max_messages) },
41 { "data_timeout", opt_time,
42 (void *)offsetof(smtp_transport_options_block, data_timeout) },
43 { "delay_after_cutoff", opt_bool,
44 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
46 { "dkim_canon", opt_stringptr,
47 (void *)offsetof(smtp_transport_options_block, dkim_canon) },
48 { "dkim_domain", opt_stringptr,
49 (void *)offsetof(smtp_transport_options_block, dkim_domain) },
50 { "dkim_private_key", opt_stringptr,
51 (void *)offsetof(smtp_transport_options_block, dkim_private_key) },
52 { "dkim_selector", opt_stringptr,
53 (void *)offsetof(smtp_transport_options_block, dkim_selector) },
54 { "dkim_sign_headers", opt_stringptr,
55 (void *)offsetof(smtp_transport_options_block, dkim_sign_headers) },
56 { "dkim_strict", opt_stringptr,
57 (void *)offsetof(smtp_transport_options_block, dkim_strict) },
59 { "dns_qualify_single", opt_bool,
60 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
61 { "dns_search_parents", opt_bool,
62 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
63 { "dnssec_request_domains", opt_stringptr,
64 (void *)offsetof(smtp_transport_options_block, dnssec_request_domains) },
65 { "dnssec_require_domains", opt_stringptr,
66 (void *)offsetof(smtp_transport_options_block, dnssec_require_domains) },
67 { "dscp", opt_stringptr,
68 (void *)offsetof(smtp_transport_options_block, dscp) },
69 { "fallback_hosts", opt_stringptr,
70 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
71 { "final_timeout", opt_time,
72 (void *)offsetof(smtp_transport_options_block, final_timeout) },
73 { "gethostbyname", opt_bool,
74 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
76 /* These are no longer honoured, as of Exim 4.80; for now, we silently
77 ignore; 4.83 will warn, and a later-still release will remove
78 these options, so that using them becomes an error. */
79 { "gnutls_require_kx", opt_stringptr,
80 (void *)offsetof(smtp_transport_options_block, gnutls_require_kx) },
81 { "gnutls_require_mac", opt_stringptr,
82 (void *)offsetof(smtp_transport_options_block, gnutls_require_mac) },
83 { "gnutls_require_protocols", opt_stringptr,
84 (void *)offsetof(smtp_transport_options_block, gnutls_require_proto) },
86 { "helo_data", opt_stringptr,
87 (void *)offsetof(smtp_transport_options_block, helo_data) },
88 { "hosts", opt_stringptr,
89 (void *)offsetof(smtp_transport_options_block, hosts) },
90 { "hosts_avoid_esmtp", opt_stringptr,
91 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
92 { "hosts_avoid_pipelining", opt_stringptr,
93 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
95 { "hosts_avoid_tls", opt_stringptr,
96 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
98 { "hosts_max_try", opt_int,
99 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
100 { "hosts_max_try_hardlimit", opt_int,
101 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
103 { "hosts_nopass_tls", opt_stringptr,
104 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
106 { "hosts_override", opt_bool,
107 (void *)offsetof(smtp_transport_options_block, hosts_override) },
108 { "hosts_randomize", opt_bool,
109 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
110 #if defined(SUPPORT_TLS) && !defined(DISABLE_OCSP)
111 { "hosts_request_ocsp", opt_stringptr,
112 (void *)offsetof(smtp_transport_options_block, hosts_request_ocsp) },
114 { "hosts_require_auth", opt_stringptr,
115 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
117 # ifdef EXPERIMENTAL_DANE
118 { "hosts_require_dane", opt_stringptr,
119 (void *)offsetof(smtp_transport_options_block, hosts_require_dane) },
121 # ifndef DISABLE_OCSP
122 { "hosts_require_ocsp", opt_stringptr,
123 (void *)offsetof(smtp_transport_options_block, hosts_require_ocsp) },
125 { "hosts_require_tls", opt_stringptr,
126 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
128 { "hosts_try_auth", opt_stringptr,
129 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
130 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
131 { "hosts_try_dane", opt_stringptr,
132 (void *)offsetof(smtp_transport_options_block, hosts_try_dane) },
135 { "hosts_try_prdr", opt_stringptr,
136 (void *)offsetof(smtp_transport_options_block, hosts_try_prdr) },
139 { "hosts_verify_avoid_tls", opt_stringptr,
140 (void *)offsetof(smtp_transport_options_block, hosts_verify_avoid_tls) },
142 { "interface", opt_stringptr,
143 (void *)offsetof(smtp_transport_options_block, interface) },
144 { "keepalive", opt_bool,
145 (void *)offsetof(smtp_transport_options_block, keepalive) },
146 { "lmtp_ignore_quota", opt_bool,
147 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
148 { "max_rcpt", opt_int | opt_public,
149 (void *)offsetof(transport_instance, max_addresses) },
150 { "multi_domain", opt_expand_bool | opt_public,
151 (void *)offsetof(transport_instance, multi_domain) },
152 { "port", opt_stringptr,
153 (void *)offsetof(smtp_transport_options_block, port) },
154 { "protocol", opt_stringptr,
155 (void *)offsetof(smtp_transport_options_block, protocol) },
156 { "retry_include_ip_address", opt_expand_bool,
157 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
158 { "serialize_hosts", opt_stringptr,
159 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
160 { "size_addition", opt_int,
161 (void *)offsetof(smtp_transport_options_block, size_addition) }
162 #ifdef EXPERIMENTAL_SOCKS
163 ,{ "socks_proxy", opt_stringptr,
164 (void *)offsetof(smtp_transport_options_block, socks_proxy) }
167 ,{ "tls_certificate", opt_stringptr,
168 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
169 { "tls_crl", opt_stringptr,
170 (void *)offsetof(smtp_transport_options_block, tls_crl) },
171 { "tls_dh_min_bits", opt_int,
172 (void *)offsetof(smtp_transport_options_block, tls_dh_min_bits) },
173 { "tls_privatekey", opt_stringptr,
174 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
175 { "tls_require_ciphers", opt_stringptr,
176 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
177 { "tls_sni", opt_stringptr,
178 (void *)offsetof(smtp_transport_options_block, tls_sni) },
179 { "tls_tempfail_tryclear", opt_bool,
180 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
181 { "tls_try_verify_hosts", opt_stringptr,
182 (void *)offsetof(smtp_transport_options_block, tls_try_verify_hosts) },
183 { "tls_verify_cert_hostnames", opt_stringptr,
184 (void *)offsetof(smtp_transport_options_block,tls_verify_cert_hostnames)},
185 { "tls_verify_certificates", opt_stringptr,
186 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) },
187 { "tls_verify_hosts", opt_stringptr,
188 (void *)offsetof(smtp_transport_options_block, tls_verify_hosts) }
192 /* Size of the options list. An extern variable has to be used so that its
193 address can appear in the tables drtables.c. */
195 int smtp_transport_options_count =
196 sizeof(smtp_transport_options)/sizeof(optionlist);
198 /* Default private options block for the smtp transport. */
200 smtp_transport_options_block smtp_transport_option_defaults = {
202 NULL, /* fallback_hosts */
204 NULL, /* fallback_hostlist */
205 NULL, /* authenticated_sender */
206 US"$primary_hostname", /* helo_data */
207 NULL, /* interface */
209 US"smtp", /* protocol */
211 NULL, /* serialize_hosts */
212 NULL, /* hosts_try_auth */
213 NULL, /* hosts_require_auth */
214 #ifdef EXPERIMENTAL_DANE
215 NULL, /* hosts_try_dane */
216 NULL, /* hosts_require_dane */
219 US"*", /* hosts_try_prdr */
222 US"*", /* hosts_request_ocsp (except under DANE; tls_client_start()) */
223 NULL, /* hosts_require_ocsp */
225 NULL, /* hosts_require_tls */
226 NULL, /* hosts_avoid_tls */
227 NULL, /* hosts_verify_avoid_tls */
228 NULL, /* hosts_avoid_pipelining */
229 NULL, /* hosts_avoid_esmtp */
230 NULL, /* hosts_nopass_tls */
231 5*60, /* command_timeout */
232 5*60, /* connect_timeout; shorter system default overrides */
233 5*60, /* data timeout */
234 10*60, /* final timeout */
235 1024, /* size_addition */
236 5, /* hosts_max_try */
237 50, /* hosts_max_try_hardlimit */
238 TRUE, /* address_retry_include_sender */
239 FALSE, /* allow_localhost */
240 FALSE, /* authenticated_sender_force */
241 FALSE, /* gethostbyname */
242 TRUE, /* dns_qualify_single */
243 FALSE, /* dns_search_parents */
244 NULL, /* dnssec_request_domains */
245 NULL, /* dnssec_require_domains */
246 TRUE, /* delay_after_cutoff */
247 FALSE, /* hosts_override */
248 FALSE, /* hosts_randomize */
249 TRUE, /* keepalive */
250 FALSE, /* lmtp_ignore_quota */
251 NULL, /* expand_retry_include_ip_address */
252 TRUE /* retry_include_ip_address */
253 #ifdef EXPERIMENTAL_SOCKS
254 ,NULL /* socks_proxy */
257 ,NULL, /* tls_certificate */
259 NULL, /* tls_privatekey */
260 NULL, /* tls_require_ciphers */
261 NULL, /* gnutls_require_kx */
262 NULL, /* gnutls_require_mac */
263 NULL, /* gnutls_require_proto */
265 US"system", /* tls_verify_certificates */
266 EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
267 /* tls_dh_min_bits */
268 TRUE, /* tls_tempfail_tryclear */
269 NULL, /* tls_verify_hosts */
270 US"*", /* tls_try_verify_hosts */
271 US"*" /* tls_verify_cert_hostnames */
274 ,NULL, /* dkim_canon */
275 NULL, /* dkim_domain */
276 NULL, /* dkim_private_key */
277 NULL, /* dkim_selector */
278 NULL, /* dkim_sign_headers */
279 NULL /* dkim_strict */
283 /* some DSN flags for use later */
285 static int rf_list[] = {rf_notify_never, rf_notify_success,
286 rf_notify_failure, rf_notify_delay };
288 static uschar *rf_names[] = { US"NEVER", US"SUCCESS", US"FAILURE", US"DELAY" };
294 static uschar *smtp_command; /* Points to last cmd for error messages */
295 static uschar *mail_command; /* Points to MAIL cmd for error messages */
296 static BOOL update_waiting; /* TRUE to update the "wait" database */
299 /*************************************************
300 * Setup entry point *
301 *************************************************/
303 /* This function is called when the transport is about to be used,
304 but before running it in a sub-process. It is used for two things:
306 (1) To set the fallback host list in addresses, when delivering.
307 (2) To pass back the interface, port, protocol, and other options, for use
308 during callout verification.
311 tblock pointer to the transport instance block
312 addrlist list of addresses about to be transported
313 tf if not NULL, pointer to block in which to return options
314 uid the uid that will be set (not used)
315 gid the gid that will be set (not used)
316 errmsg place for error message (not used)
318 Returns: OK always (FAIL, DEFER not used)
322 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
323 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
325 smtp_transport_options_block *ob =
326 (smtp_transport_options_block *)(tblock->options_block);
328 errmsg = errmsg; /* Keep picky compilers happy */
332 /* Pass back options if required. This interface is getting very messy. */
336 tf->interface = ob->interface;
338 tf->protocol = ob->protocol;
339 tf->hosts = ob->hosts;
340 tf->hosts_override = ob->hosts_override;
341 tf->hosts_randomize = ob->hosts_randomize;
342 tf->gethostbyname = ob->gethostbyname;
343 tf->qualify_single = ob->dns_qualify_single;
344 tf->search_parents = ob->dns_search_parents;
345 tf->helo_data = ob->helo_data;
348 /* Set the fallback host list for all the addresses that don't have fallback
349 host lists, provided that the local host wasn't present in the original host
352 if (!testflag(addrlist, af_local_host_removed))
354 for (; addrlist != NULL; addrlist = addrlist->next)
355 if (addrlist->fallback_hosts == NULL)
356 addrlist->fallback_hosts = ob->fallback_hostlist;
364 /*************************************************
365 * Initialization entry point *
366 *************************************************/
368 /* Called for each instance, after its options have been read, to
369 enable consistency checks to be done, or anything else that needs
372 Argument: pointer to the transport instance block
377 smtp_transport_init(transport_instance *tblock)
379 smtp_transport_options_block *ob =
380 (smtp_transport_options_block *)(tblock->options_block);
382 /* Retry_use_local_part defaults FALSE if unset */
384 if (tblock->retry_use_local_part == TRUE_UNSET)
385 tblock->retry_use_local_part = FALSE;
387 /* Set the default port according to the protocol */
389 if (ob->port == NULL)
390 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
391 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
393 /* Set up the setup entry point, to be called before subprocesses for this
396 tblock->setup = smtp_transport_setup;
398 /* Complain if any of the timeouts are zero. */
400 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
401 ob->final_timeout <= 0)
402 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
403 "command, data, or final timeout value is zero for %s transport",
406 /* If hosts_override is set and there are local hosts, set the global
407 flag that stops verify from showing router hosts. */
409 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
411 /* If there are any fallback hosts listed, build a chain of host items
412 for them, but do not do any lookups at this time. */
414 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
417 if ( ob->gnutls_require_kx
418 || ob->gnutls_require_mac
419 || ob->gnutls_require_proto)
420 log_write(0, LOG_MAIN, "WARNING: smtp transport options"
421 " gnutls_require_kx, gnutls_require_mac and gnutls_require_protocols"
430 /*************************************************
431 * Set delivery info into all active addresses *
432 *************************************************/
434 /* Only addresses whose status is >= PENDING are relevant. A lesser
435 status means that an address is not currently being processed.
438 addrlist points to a chain of addresses
439 errno_value to put in each address's errno field
440 msg to put in each address's message field
441 rc to put in each address's transport_return field
442 pass_message if TRUE, set the "pass message" flag in the address
443 host if set, mark addrs as having used this host
445 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
446 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
447 this particular type of timeout.
453 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
454 BOOL pass_message, host_item * host)
458 if (errno_value == ERRNO_CONNECTTIMEOUT)
460 errno_value = ETIMEDOUT;
461 orvalue = RTEF_CTOUT;
463 for (addr = addrlist; addr != NULL; addr = addr->next)
464 if (addr->transport_return >= PENDING)
466 addr->basic_errno = errno_value;
467 addr->more_errno |= orvalue;
471 if (pass_message) setflag(addr, af_pass_message);
473 addr->transport_return = rc;
475 addr->host_used = host;
481 /*************************************************
482 * Check an SMTP response *
483 *************************************************/
485 /* This function is given an errno code and the SMTP response buffer
486 to analyse, together with the host identification for generating messages. It
487 sets an appropriate message and puts the first digit of the response code into
488 the yield variable. If no response was actually read, a suitable digit is
492 host the current host, to get its name for messages
493 errno_value pointer to the errno value
494 more_errno from the top address for use with ERRNO_FILTER_FAIL
495 buffer the SMTP response buffer
496 yield where to put a one-digit SMTP response code
497 message where to put an errror message
498 pass_message set TRUE if message is an SMTP response
500 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
504 check_response(host_item *host, int *errno_value, int more_errno,
505 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
509 if (smtp_use_pipelining &&
510 (Ustrcmp(smtp_command, "MAIL") == 0 ||
511 Ustrcmp(smtp_command, "RCPT") == 0 ||
512 Ustrcmp(smtp_command, "DATA") == 0))
515 *yield = '4'; /* Default setting is to give a temporary error */
517 /* Handle response timeout */
519 if (*errno_value == ETIMEDOUT)
521 *message = US string_sprintf("SMTP timeout after %s%s",
523 if (transport_count > 0)
524 *message = US string_sprintf("%s (%d bytes written)", *message,
529 /* Handle malformed SMTP response */
531 if (*errno_value == ERRNO_SMTPFORMAT)
533 const uschar *malfresp = string_printing(buffer);
534 while (isspace(*malfresp)) malfresp++;
535 *message = *malfresp == 0
536 ? string_sprintf("Malformed SMTP reply (an empty line) "
537 "in response to %s%s", pl, smtp_command)
538 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
539 pl, smtp_command, malfresp);
543 /* Handle a failed filter process error; can't send QUIT as we mustn't
546 if (*errno_value == ERRNO_FILTER_FAIL)
548 *message = US string_sprintf("transport filter process failed (%d)%s",
550 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
554 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
557 if (*errno_value == ERRNO_CHHEADER_FAIL)
560 US string_sprintf("failed to expand headers_add or headers_remove: %s",
561 expand_string_message);
565 /* Handle failure to write a complete data block */
567 if (*errno_value == ERRNO_WRITEINCOMPLETE)
569 *message = US string_sprintf("failed to write a data block");
573 /* Handle error responses from the remote mailer. */
577 const uschar *s = string_printing(buffer);
578 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
579 "%s", pl, smtp_command, s);
580 *pass_message = TRUE;
585 /* No data was read. If there is no errno, this must be the EOF (i.e.
586 connection closed) case, which causes deferral. An explicit connection reset
587 error has the same effect. Otherwise, put the host's identity in the message,
588 leaving the errno value to be interpreted as well. In all cases, we have to
589 assume the connection is now dead. */
591 if (*errno_value == 0 || *errno_value == ECONNRESET)
593 *errno_value = ERRNO_SMTPCLOSED;
594 *message = US string_sprintf("Remote host closed connection "
595 "in response to %s%s", pl, smtp_command);
597 else *message = US string_sprintf("%s [%s]", host->name, host->address);
604 /*************************************************
605 * Write error message to logs *
606 *************************************************/
608 /* This writes to the main log and to the message log.
611 addr the address item containing error information
612 host the current host
618 write_logs(address_item *addr, host_item *host)
620 uschar * message = string_sprintf("H=%s [%s]", host->name, host->address);
624 message = string_sprintf("%s: %s", message, addr->message);
625 if (addr->basic_errno > 0)
626 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
627 log_write(0, LOG_MAIN, "%s", message);
628 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
632 if (log_extra_selector & LX_outgoing_port)
633 message = string_sprintf("%s:%d", message,
634 host->port == PORT_NONE ? 25 : host->port);
635 log_write(0, LOG_MAIN, "%s %s", message, strerror(addr->basic_errno));
636 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), message,
637 strerror(addr->basic_errno));
642 msglog_line(host_item * host, uschar * message)
644 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
645 host->name, host->address, message);
650 #ifdef EXPERIMENTAL_EVENT
651 /*************************************************
652 * Post-defer action *
653 *************************************************/
655 /* This expands an arbitrary per-transport string.
656 It might, for example, be used to write to the database log.
659 addr the address item containing error information
660 host the current host
666 deferred_event_raise(address_item *addr, host_item *host)
668 uschar * action = addr->transport->event_action;
669 const uschar * save_domain;
675 save_domain = deliver_domain;
676 save_local = deliver_localpart;
678 /*XXX would ip & port already be set up? */
679 deliver_host_address = string_copy(host->address);
680 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
681 event_defer_errno = addr->basic_errno;
683 router_name = addr->router->name;
684 transport_name = addr->transport->name;
685 deliver_domain = addr->domain;
686 deliver_localpart = addr->local_part;
688 (void) event_raise(action, US"msg:host:defer",
690 ? addr->basic_errno > 0
691 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
692 : string_copy(addr->message)
693 : addr->basic_errno > 0
694 ? string_copy(US strerror(addr->basic_errno))
697 deliver_localpart = save_local;
698 deliver_domain = save_domain;
699 router_name = transport_name = NULL;
703 /*************************************************
704 * Synchronize SMTP responses *
705 *************************************************/
707 /* This function is called from smtp_deliver() to receive SMTP responses from
708 the server, and match them up with the commands to which they relate. When
709 PIPELINING is not in use, this function is called after every command, and is
710 therefore somewhat over-engineered, but it is simpler to use a single scheme
711 that works both with and without PIPELINING instead of having two separate sets
714 The set of commands that are buffered up with pipelining may start with MAIL
715 and may end with DATA; in between are RCPT commands that correspond to the
716 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
717 etc.) are never buffered.
719 Errors after MAIL or DATA abort the whole process leaving the response in the
720 buffer. After MAIL, pending responses are flushed, and the original command is
721 re-instated in big_buffer for error messages. For RCPT commands, the remote is
722 permitted to reject some recipient addresses while accepting others. However
723 certain errors clearly abort the whole process. Set the value in
724 transport_return to PENDING_OK if the address is accepted. If there is a
725 subsequent general error, it will get reset accordingly. If not, it will get
726 converted to OK at the end.
729 addrlist the complete address list
730 include_affixes TRUE if affixes include in RCPT
731 sync_addr ptr to the ptr of the one to start scanning at (updated)
732 host the host we are connected to
733 count the number of responses to read
735 include_sender true if 4xx retry is to include the sender it its key
736 pending_MAIL true if the first response is for MAIL
737 pending_DATA 0 if last command sent was not DATA
738 +1 if previously had a good recipient
739 -1 if not previously had a good recipient
740 inblock incoming SMTP block
741 timeout timeout value
742 buffer buffer for reading response
743 buffsize size of buffer
745 Returns: 3 if at least one address had 2xx and one had 5xx
746 2 if at least one address had 5xx but none had 2xx
747 1 if at least one host had a 2xx response, but none had 5xx
748 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
749 -1 timeout while reading RCPT response
750 -2 I/O or other non-response error for RCPT
751 -3 DATA or MAIL failed - errno and buffer set
755 sync_responses(address_item *addrlist, BOOL include_affixes,
756 address_item **sync_addr, host_item *host, int count,
757 BOOL address_retry_include_sender, BOOL pending_MAIL,
758 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
761 address_item *addr = *sync_addr;
764 /* Handle the response for a MAIL command. On error, reinstate the original
765 command in big_buffer for error message use, and flush any further pending
766 responses before returning, except after I/O errors and timeouts. */
771 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
773 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
774 if (errno == 0 && buffer[0] != 0)
776 uschar flushbuffer[4096];
778 if (buffer[0] == '4')
780 save_errno = ERRNO_MAIL4XX;
781 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
785 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
787 && (errno != 0 || flushbuffer[0] == 0))
793 if (pending_DATA) count--; /* Number of RCPT responses to come */
794 while (count-- > 0) /* Mark any pending addrs with the host used */
796 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
797 addr->host_used = host;
804 if (pending_DATA) count--; /* Number of RCPT responses to come */
806 /* Read and handle the required number of RCPT responses, matching each one up
807 with an address by scanning for the next address whose status is PENDING_DEFER.
812 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
814 /* The address was accepted */
815 addr->host_used = host;
817 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
820 addr->transport_return = PENDING_OK;
822 /* If af_dr_retry_exists is set, there was a routing delay on this address;
823 ensure that any address-specific retry record is expunged. We do this both
824 for the basic key and for the version that also includes the sender. */
826 if (testflag(addr, af_dr_retry_exists))
828 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
830 retry_add_item(addr, altkey, rf_delete);
831 retry_add_item(addr, addr->address_retry_key, rf_delete);
835 /* Timeout while reading the response */
837 else if (errno == ETIMEDOUT)
839 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
840 transport_rcpt_address(addr, include_affixes));
841 set_errno(addrlist, ETIMEDOUT, message, DEFER, FALSE, NULL);
842 retry_add_item(addr, addr->address_retry_key, 0);
843 update_waiting = FALSE;
847 /* Handle other errors in obtaining an SMTP response by returning -1. This
848 will cause all the addresses to be deferred. Restore the SMTP command in
849 big_buffer for which we are checking the response, so the error message
852 else if (errno != 0 || buffer[0] == 0)
854 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
855 transport_rcpt_address(addr, include_affixes));
859 /* Handle SMTP permanent and temporary response codes. */
864 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
865 "%s", transport_rcpt_address(addr, include_affixes),
866 string_printing(buffer));
867 setflag(addr, af_pass_message);
868 msglog_line(host, addr->message);
870 /* The response was 5xx */
872 if (buffer[0] == '5')
874 addr->transport_return = FAIL;
878 /* The response was 4xx */
882 addr->transport_return = DEFER;
883 addr->basic_errno = ERRNO_RCPT4XX;
884 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
886 /* Log temporary errors if there are more hosts to be tried.
887 If not, log this last one in the == line. */
890 log_write(0, LOG_MAIN, "H=%s [%s]: %s", host->name, host->address, addr->message);
892 /* Do not put this message on the list of those waiting for specific
893 hosts, as otherwise it is likely to be tried too often. */
895 update_waiting = FALSE;
897 /* Add a retry item for the address so that it doesn't get tried again
898 too soon. If address_retry_include_sender is true, add the sender address
901 if (address_retry_include_sender)
903 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
905 retry_add_item(addr, altkey, 0);
907 else retry_add_item(addr, addr->address_retry_key, 0);
910 } /* Loop for next RCPT response */
912 /* Update where to start at for the next block of responses, unless we
913 have already handled all the addresses. */
915 if (addr != NULL) *sync_addr = addr->next;
917 /* Handle a response to DATA. If we have not had any good recipients, either
918 previously or in this block, the response is ignored. */
920 if (pending_DATA != 0 &&
921 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
926 if (pending_DATA > 0 || (yield & 1) != 0)
928 if (errno == 0 && buffer[0] == '4')
930 errno = ERRNO_DATA4XX;
931 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
935 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
936 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
937 "is in use and there were no good recipients\n", msg);
940 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
941 present) received 3xx. If any RCPTs were handled and yielded anything other
942 than 4xx, yield will be set non-zero. */
949 /* Do the client side of smtp-level authentication */
952 buffer EHLO response from server (gets overwritten)
953 addrlist chain of potential addresses to deliver
954 host host to deliver to
956 ibp, obp comms channel control blocks
959 OK Success, or failed (but not required): global "smtp_authenticated" set
960 DEFER Failed authentication (and was required)
961 ERROR Internal problem
963 FAIL_SEND Failed communications - transmit
968 smtp_auth(uschar *buffer, unsigned bufsize, address_item *addrlist, host_item *host,
969 smtp_transport_options_block *ob, BOOL is_esmtp,
970 smtp_inblock *ibp, smtp_outblock *obp)
973 uschar *fail_reason = US"server did not advertise AUTH support";
975 smtp_authenticated = FALSE;
976 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
977 require_auth = verify_check_given_host(&ob->hosts_require_auth, host);
979 if (is_esmtp && !regex_AUTH) regex_AUTH =
980 regex_must_compile(US"\\n250[\\s\\-]AUTH\\s+([\\-\\w\\s]+)(?:\\n|$)",
983 if (is_esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
985 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
986 expand_nmax = -1; /* reset */
988 /* Must not do this check until after we have saved the result of the
989 regex match above. */
991 if (require_auth == OK ||
992 verify_check_given_host(&ob->hosts_try_auth, host) == OK)
995 fail_reason = US"no common mechanisms were found";
997 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
999 /* Scan the configured authenticators looking for one which is configured
1000 for use as a client, which is not suppressed by client_condition, and
1001 whose name matches an authentication mechanism supported by the server.
1002 If one is found, attempt to authenticate by calling its client function.
1005 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1009 (au->client_condition != NULL &&
1010 !expand_check_condition(au->client_condition, au->name,
1011 US"client authenticator")))
1013 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1015 (au->client)? "client_condition is false" :
1016 "not configured as a client");
1020 /* Loop to scan supported server mechanisms */
1025 int len = Ustrlen(au->public_name);
1026 while (isspace(*p)) p++;
1028 if (strncmpic(au->public_name, p, len) != 0 ||
1029 (p[len] != 0 && !isspace(p[len])))
1031 while (*p != 0 && !isspace(*p)) p++;
1035 /* Found data for a listed mechanism. Call its client entry. Set
1036 a flag in the outblock so that data is overwritten after sending so
1037 that reflections don't show it. */
1039 fail_reason = US"authentication attempt(s) failed";
1040 obp->authenticating = TRUE;
1041 rc = (au->info->clientcode)(au, ibp, obp,
1042 ob->command_timeout, buffer, bufsize);
1043 obp->authenticating = FALSE;
1044 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1047 /* A temporary authentication failure must hold up delivery to
1048 this host. After a permanent authentication failure, we carry on
1049 to try other authentication methods. If all fail hard, try to
1050 deliver the message unauthenticated unless require_auth was set. */
1055 smtp_authenticated = TRUE; /* stops the outer loop */
1056 client_authenticator = au->name;
1057 if (au->set_client_id != NULL)
1058 client_authenticated_id = expand_string(au->set_client_id);
1061 /* Failure after writing a command */
1066 /* Failure after reading a response */
1069 if (errno != 0 || buffer[0] != '5') return FAIL;
1070 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1071 au->name, host->name, host->address, buffer);
1074 /* Failure by some other means. In effect, the authenticator
1075 decided it wasn't prepared to handle this case. Typically this
1076 is the result of "fail" in an expansion string. Do we need to
1077 log anything here? Feb 2006: a message is now put in the buffer
1078 if logging is required. */
1082 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1083 "authentication H=%s [%s] %s", au->name, host->name,
1084 host->address, buffer);
1087 /* Internal problem, message in buffer. */
1090 set_errno(addrlist, ERRNO_AUTHPROB, string_copy(buffer),
1091 DEFER, FALSE, NULL);
1095 break; /* If not authenticated, try next authenticator */
1096 } /* Loop for scanning supported server mechanisms */
1097 } /* Loop for further authenticators */
1101 /* If we haven't authenticated, but are required to, give up. */
1103 if (require_auth == OK && !smtp_authenticated)
1105 set_errno(addrlist, ERRNO_AUTHFAIL,
1106 string_sprintf("authentication required but %s", fail_reason), DEFER,
1115 /* Construct AUTH appendix string for MAIL TO */
1118 buffer to build string
1119 addrlist chain of potential addresses to deliver
1120 ob transport options
1122 Globals smtp_authenticated
1123 client_authenticated_sender
1124 Return True on error, otherwise buffer has (possibly empty) terminated string
1128 smtp_mail_auth_str(uschar *buffer, unsigned bufsize, address_item *addrlist,
1129 smtp_transport_options_block *ob)
1131 uschar *local_authenticated_sender = authenticated_sender;
1134 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n", authenticated_sender, ob->authenticated_sender, smtp_authenticated?"Y":"N");
1137 if (ob->authenticated_sender != NULL)
1139 uschar *new = expand_string(ob->authenticated_sender);
1142 if (!expand_string_forcedfail)
1144 uschar *message = string_sprintf("failed to expand "
1145 "authenticated_sender: %s", expand_string_message);
1146 set_errno(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, NULL);
1150 else if (new[0] != 0) local_authenticated_sender = new;
1153 /* Add the authenticated sender address if present */
1155 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1156 local_authenticated_sender != NULL)
1158 string_format(buffer, bufsize, " AUTH=%s",
1159 auth_xtextencode(local_authenticated_sender,
1160 Ustrlen(local_authenticated_sender)));
1161 client_authenticated_sender = string_copy(local_authenticated_sender);
1171 #ifdef EXPERIMENTAL_DANE
1173 tlsa_lookup(const host_item * host, dns_answer * dnsa,
1174 BOOL dane_required, BOOL * dane)
1176 /* move this out to host.c given the similarity to dns_lookup() ? */
1178 const uschar * fullname = buffer;
1180 /* TLSA lookup string */
1181 (void)sprintf(CS buffer, "_%d._tcp.%.256s", host->port, host->name);
1183 switch (dns_lookup(dnsa, buffer, T_TLSA, &fullname))
1186 return DEFER; /* just defer this TLS'd conn */
1192 log_write(0, LOG_MAIN, "DANE error: TLSA lookup failed");
1198 if (!dns_is_secure(dnsa))
1200 log_write(0, LOG_MAIN, "DANE error: TLSA lookup not DNSSEC");
1212 typedef struct smtp_compare_s
1214 uschar *current_sender_address;
1215 struct transport_instance *tblock;
1219 Create a unique string that identifies this message, it is based on
1220 sender_address, helo_data and tls_certificate if enabled. */
1223 smtp_local_identity(uschar * sender, struct transport_instance * tblock)
1225 address_item * addr1;
1226 uschar * if1 = US"";
1227 uschar * helo1 = US"";
1229 uschar * tlsc1 = US"";
1231 uschar * save_sender_address = sender_address;
1232 uschar * local_identity = NULL;
1233 smtp_transport_options_block * ob =
1234 (smtp_transport_options_block *)tblock->options_block;
1236 sender_address = sender;
1238 addr1 = deliver_make_addr (sender, TRUE);
1239 deliver_set_expansions(addr1);
1242 if1 = expand_string(ob->interface);
1245 helo1 = expand_string(ob->helo_data);
1248 if (ob->tls_certificate)
1249 tlsc1 = expand_string(ob->tls_certificate);
1250 local_identity = string_sprintf ("%s^%s^%s", if1, helo1, tlsc1);
1252 local_identity = string_sprintf ("%s^%s", if1, helo1);
1255 deliver_set_expansions(NULL);
1256 sender_address = save_sender_address;
1258 return local_identity;
1263 /* This routine is a callback that is called from transport_check_waiting.
1264 This function will evaluate the incoming message versus the previous
1265 message. If the incoming message is using a different local identity then
1266 we will veto this new message. */
1269 smtp_are_same_identities(uschar * message_id, smtp_compare_t * s_compare)
1271 uschar * save_sender_address = sender_address;
1272 uschar * current_local_identity =
1273 smtp_local_identity(s_compare->current_sender_address, s_compare->tblock);
1274 uschar * new_sender_address = deliver_get_sender_address(message_id);
1275 uschar * message_local_identity =
1276 smtp_local_identity(new_sender_address, s_compare->tblock);
1278 sender_address = save_sender_address;
1280 return Ustrcmp(current_local_identity, message_local_identity) == 0;
1285 /*************************************************
1286 * Deliver address list to given host *
1287 *************************************************/
1289 /* If continue_hostname is not null, we get here only when continuing to
1290 deliver down an existing channel. The channel was passed as the standard
1291 input. TLS is never active on a passed channel; the previous process always
1292 closes it down before passing the connection on.
1294 Otherwise, we have to make a connection to the remote host, and do the
1295 initial protocol exchange.
1297 When running as an MUA wrapper, if the sender or any recipient is rejected,
1298 temporarily or permanently, we force failure for all recipients.
1301 addrlist chain of potential addresses to deliver; only those whose
1302 transport_return field is set to PENDING_DEFER are currently
1303 being processed; others should be skipped - they have either
1304 been delivered to an earlier host or IP address, or been
1305 failed by one of them.
1306 host host to deliver to
1307 host_af AF_INET or AF_INET6
1308 port default TCP/IP port to use, in host byte order
1309 interface interface to bind to, or NULL
1310 tblock transport instance block
1311 message_defer set TRUE if yield is OK, but all addresses were deferred
1312 because of a non-recipient, non-host failure, that is, a
1313 4xx response to MAIL FROM, DATA, or ".". This is a defer
1314 that is specific to the message.
1315 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1316 a second attempt after TLS initialization fails
1318 Returns: OK - the connection was made and the delivery attempted;
1319 the result for each address is in its data block.
1320 DEFER - the connection could not be made, or something failed
1321 while setting up the SMTP session, or there was a
1322 non-message-specific error, such as a timeout.
1323 ERROR - a filter command is specified for this transport,
1324 and there was a problem setting it up; OR helo_data
1325 or add_headers or authenticated_sender is specified
1326 for this transport, and the string failed to expand
1330 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
1331 uschar *interface, transport_instance *tblock,
1332 BOOL *message_defer, BOOL suppress_tls)
1335 address_item *sync_addr;
1336 address_item *first_addr = addrlist;
1341 time_t start_delivery_time = time(NULL);
1342 smtp_transport_options_block *ob =
1343 (smtp_transport_options_block *)(tblock->options_block);
1344 BOOL lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
1345 BOOL smtps = strcmpic(ob->protocol, US"smtps") == 0;
1347 BOOL send_rset = TRUE;
1348 BOOL send_quit = TRUE;
1349 BOOL setting_up = TRUE;
1350 BOOL completed_address = FALSE;
1353 BOOL pass_message = FALSE;
1354 #ifndef DISABLE_PRDR
1355 BOOL prdr_offered = FALSE;
1358 #ifdef EXPERIMENTAL_INTERNATIONAL
1359 BOOL utf8_offered = FALSE;
1361 BOOL dsn_all_lasthop = TRUE;
1362 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1365 dns_answer tlsa_dnsa;
1367 smtp_inblock inblock;
1368 smtp_outblock outblock;
1369 int max_rcpt = tblock->max_addresses;
1370 uschar *igquotstr = US"";
1372 uschar *helo_data = NULL;
1374 uschar *message = NULL;
1375 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
1377 uschar buffer[4096];
1378 uschar inbuffer[4096];
1379 uschar outbuffer[4096];
1380 address_item * current_address;
1382 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
1384 *message_defer = FALSE;
1385 smtp_command = US"initial connection";
1386 if (max_rcpt == 0) max_rcpt = 999999;
1388 /* Set up the buffer for reading SMTP response packets. */
1390 inblock.buffer = inbuffer;
1391 inblock.buffersize = sizeof(inbuffer);
1392 inblock.ptr = inbuffer;
1393 inblock.ptrend = inbuffer;
1395 /* Set up the buffer for holding SMTP commands while pipelining */
1397 outblock.buffer = outbuffer;
1398 outblock.buffersize = sizeof(outbuffer);
1399 outblock.ptr = outbuffer;
1400 outblock.cmd_count = 0;
1401 outblock.authenticating = FALSE;
1403 /* Reset the parameters of a TLS session. */
1406 tls_out.cipher = NULL; /* the one we may use for this transport */
1407 tls_out.ourcert = NULL;
1408 tls_out.peercert = NULL;
1409 tls_out.peerdn = NULL;
1410 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1413 tls_out.ocsp = OCSP_NOT_REQ;
1415 /* Flip the legacy TLS-related variables over to the outbound set in case
1416 they're used in the context of the transport. Don't bother resetting
1417 afterward as we're in a subprocess. */
1419 tls_modify_variables(&tls_out);
1424 set_errno(addrlist, ERRNO_TLSFAILURE, US"TLS support not available",
1425 DEFER, FALSE, NULL);
1430 /* Make a connection to the host if this isn't a continued delivery, and handle
1431 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
1432 specially so they can be identified for retries. */
1434 if (continue_hostname == NULL)
1436 /* This puts port into host->port */
1437 inblock.sock = outblock.sock =
1438 smtp_connect(host, host_af, port, interface, ob->connect_timeout, tblock);
1440 if (inblock.sock < 0)
1442 set_errno(addrlist, (errno == ETIMEDOUT)? ERRNO_CONNECTTIMEOUT : errno,
1443 NULL, DEFER, FALSE, NULL);
1447 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1449 tls_out.dane_verified = FALSE;
1450 tls_out.tlsa_usage = 0;
1452 dane_required = verify_check_given_host(&ob->hosts_require_dane, host) == OK;
1454 if (host->dnssec == DS_YES)
1457 || verify_check_given_host(&ob->hosts_try_dane, host) == OK
1459 && (rc = tlsa_lookup(host, &tlsa_dnsa, dane_required, &dane)) != OK
1463 else if (dane_required)
1465 log_write(0, LOG_MAIN, "DANE error: %s lookup not DNSSEC", host->name);
1470 ob->tls_tempfail_tryclear = FALSE;
1474 /* Expand the greeting message while waiting for the initial response. (Makes
1475 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1476 delayed till here so that $sending_interface and $sending_port are set. */
1478 helo_data = expand_string(ob->helo_data);
1480 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1481 is nevertheless a reasonably clean way of programming this kind of logic,
1482 where you want to escape on any error. */
1486 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1487 ob->command_timeout)) goto RESPONSE_FAILED;
1489 #ifdef EXPERIMENTAL_EVENT
1492 lookup_dnssec_authenticated = host->dnssec==DS_YES ? US"yes"
1493 : host->dnssec==DS_NO ? US"no" : NULL;
1494 s = event_raise(tblock->event_action, US"smtp:connect", buffer);
1497 set_errno(addrlist, ERRNO_EXPANDFAIL,
1498 string_sprintf("deferred by smtp:connect event expansion: %s", s),
1499 DEFER, FALSE, NULL);
1506 /* Now check if the helo_data expansion went well, and sign off cleanly if
1509 if (helo_data == NULL)
1511 uschar *message = string_sprintf("failed to expand helo_data: %s",
1512 expand_string_message);
1513 set_errno(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, NULL);
1519 /** Debugging without sending a message
1520 addrlist->transport_return = DEFER;
1524 /* Errors that occur after this point follow an SMTP command, which is
1525 left in big_buffer by smtp_write_command() for use in error messages. */
1527 smtp_command = big_buffer;
1529 /* Tell the remote who we are...
1531 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1532 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1533 greeting is of this form. The assumption was that the far end supports it
1534 properly... but experience shows that there are some that give 5xx responses,
1535 even though the banner includes "ESMTP" (there's a bloody-minded one that
1536 says "ESMTP not spoken here"). Cope with that case.
1538 September 2000: Time has passed, and it seems reasonable now to always send
1539 EHLO at the start. It is also convenient to make the change while installing
1542 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1543 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1544 would be no way to send out the mails, so there is now a host list
1545 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1546 PIPELINING problem as well. Maybe it can also be useful to cure other
1547 problems with broken servers.
1549 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1550 Then somebody tried it with a Microsoft mailer... It seems that all other
1551 mailers use upper case for some reason (the RFC is quite clear about case
1552 independence) so, for peace of mind, I gave in. */
1554 esmtp = verify_check_given_host(&ob->hosts_avoid_esmtp, host) != OK;
1556 /* Alas; be careful, since this goto is not an error-out, so conceivably
1557 we might set data between here and the target which we assume to exist
1558 and be usable. I can see this coming back to bite us. */
1563 suppress_tls = FALSE;
1564 ob->tls_tempfail_tryclear = FALSE;
1565 smtp_command = US"SSL-on-connect";
1572 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1573 lmtp? "LHLO" : "EHLO", helo_data) < 0)
1575 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1576 ob->command_timeout))
1578 if (errno != 0 || buffer[0] == 0 || lmtp) goto RESPONSE_FAILED;
1585 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1590 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1592 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1593 ob->command_timeout)) goto RESPONSE_FAILED;
1596 /* Set IGNOREQUOTA if the response to LHLO specifies support and the
1597 lmtp_ignore_quota option was set. */
1599 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1600 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1601 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1603 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1606 tls_offered = esmtp &&
1607 pcre_exec(regex_STARTTLS, NULL, CS buffer, Ustrlen(buffer), 0,
1608 PCRE_EOPT, NULL, 0) >= 0;
1611 #ifndef DISABLE_PRDR
1612 prdr_offered = esmtp
1613 && pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(buffer), 0,
1614 PCRE_EOPT, NULL, 0) >= 0
1615 && verify_check_given_host(&ob->hosts_try_prdr, host) == OK;
1618 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1621 #ifdef EXPERIMENTAL_INTERNATIONAL
1622 utf8_offered = esmtp
1624 && pcre_exec(regex_UTF8, NULL, CS buffer, Ustrlen(buffer), 0,
1625 PCRE_EOPT, NULL, 0) >= 0;
1629 /* For continuing deliveries down the same channel, the socket is the standard
1630 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1631 below). Set up the pointer to where subsequent commands will be left, for
1632 error messages. Note that smtp_use_size and smtp_use_pipelining will have been
1633 set from the command line if they were set in the process that passed the
1638 inblock.sock = outblock.sock = fileno(stdin);
1639 smtp_command = big_buffer;
1640 host->port = port; /* Record the port that was used */
1643 /* If TLS is available on this connection, whether continued or not, attempt to
1644 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1645 send another EHLO - the server may give a different answer in secure mode. We
1646 use a separate buffer for reading the response to STARTTLS so that if it is
1647 negative, the original EHLO data is available for subsequent analysis, should
1648 the client not be required to use TLS. If the response is bad, copy the buffer
1649 for error analysis. */
1654 && verify_check_given_host(&ob->hosts_avoid_tls, host) != OK)
1656 uschar buffer2[4096];
1657 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1660 /* If there is an I/O error, transmission of this message is deferred. If
1661 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1662 false, we also defer. However, if there is a temporary rejection of STARTTLS
1663 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1664 STARTTLS, we carry on. This means we will try to send the message in clear,
1665 unless the host is in hosts_require_tls (tested below). */
1667 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1668 ob->command_timeout))
1670 if (errno != 0 || buffer2[0] == 0 ||
1671 (buffer2[0] == '4' && !ob->tls_tempfail_tryclear))
1673 Ustrncpy(buffer, buffer2, sizeof(buffer));
1674 goto RESPONSE_FAILED;
1678 /* STARTTLS accepted: try to negotiate a TLS session. */
1683 int rc = tls_client_start(inblock.sock, host, addrlist, tblock
1684 # ifdef EXPERIMENTAL_DANE
1685 , dane ? &tlsa_dnsa : NULL
1689 /* TLS negotiation failed; give an error. From outside, this function may
1690 be called again to try in clear on a new connection, if the options permit
1691 it for this host. */
1695 # ifdef EXPERIMENTAL_DANE
1696 if (rc == DEFER && dane && !dane_required)
1698 log_write(0, LOG_MAIN, "DANE attempt failed;"
1699 " trying CA-root TLS to %s [%s] (not in hosts_require_dane)",
1700 host->name, host->address);
1706 save_errno = ERRNO_TLSFAILURE;
1707 message = US"failure while setting up TLS session";
1712 /* TLS session is set up */
1714 for (addr = addrlist; addr != NULL; addr = addr->next)
1715 if (addr->transport_return == PENDING_DEFER)
1717 addr->cipher = tls_out.cipher;
1718 addr->ourcert = tls_out.ourcert;
1719 addr->peercert = tls_out.peercert;
1720 addr->peerdn = tls_out.peerdn;
1721 addr->ocsp = tls_out.ocsp;
1726 /* if smtps, we'll have smtp_command set to something else; always safe to
1728 smtp_command = big_buffer;
1730 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1731 helo_data is null, we are dealing with a connection that was passed from
1732 another process, and so we won't have expanded helo_data above. We have to
1733 expand it here. $sending_ip_address and $sending_port are set up right at the
1734 start of the Exim process (in exim.c). */
1736 if (tls_out.active >= 0)
1739 if (helo_data == NULL)
1741 helo_data = expand_string(ob->helo_data);
1742 if (helo_data == NULL)
1744 uschar *message = string_sprintf("failed to expand helo_data: %s",
1745 expand_string_message);
1746 set_errno(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, NULL);
1752 /* For SMTPS we need to wait for the initial OK response. */
1755 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1756 ob->command_timeout)) goto RESPONSE_FAILED;
1760 greeting_cmd = "EHLO";
1763 greeting_cmd = "HELO";
1765 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1768 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1769 lmtp? "LHLO" : greeting_cmd, helo_data) < 0)
1771 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1772 ob->command_timeout))
1773 goto RESPONSE_FAILED;
1776 /* If the host is required to use a secure channel, ensure that we
1780 # ifdef EXPERIMENTAL_DANE
1783 verify_check_given_host(&ob->hosts_require_tls, host) == OK
1786 save_errno = ERRNO_TLSREQUIRED;
1787 message = string_sprintf("a TLS session is required, but %s",
1788 tls_offered? "an attempt to start TLS failed" :
1789 "the server did not offer TLS support");
1792 #endif /*SUPPORT_TLS*/
1794 /* If TLS is active, we have just started it up and re-done the EHLO command,
1795 so its response needs to be analyzed. If TLS is not active and this is a
1796 continued session down a previously-used socket, we haven't just done EHLO, so
1799 if (continue_hostname == NULL
1801 || tls_out.active >= 0
1805 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
1806 lmtp_ignore_quota option was set. */
1808 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1809 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1810 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1812 /* If the response to EHLO specified support for the SIZE parameter, note
1813 this, provided size_addition is non-negative. */
1815 smtp_use_size = esmtp && ob->size_addition >= 0 &&
1816 pcre_exec(regex_SIZE, NULL, CS buffer, Ustrlen(CS buffer), 0,
1817 PCRE_EOPT, NULL, 0) >= 0;
1819 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
1820 the current host, esmtp will be false, so PIPELINING can never be used. If
1821 the current host matches hosts_avoid_pipelining, don't do it. */
1823 smtp_use_pipelining = esmtp
1824 && verify_check_given_host(&ob->hosts_avoid_pipelining, host) != OK
1825 && pcre_exec(regex_PIPELINING, NULL, CS buffer, Ustrlen(CS buffer), 0,
1826 PCRE_EOPT, NULL, 0) >= 0;
1828 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
1829 smtp_use_pipelining? "" : "not ");
1831 #ifndef DISABLE_PRDR
1832 prdr_offered = esmtp
1833 && pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(CS buffer), 0,
1834 PCRE_EOPT, NULL, 0) >= 0
1835 && verify_check_given_host(&ob->hosts_try_prdr, host) == OK;
1838 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1841 #ifdef EXPERIMENTAL_INTERNATIONAL
1842 utf8_offered = esmtp
1844 && pcre_exec(regex_UTF8, NULL, CS buffer, Ustrlen(buffer), 0,
1845 PCRE_EOPT, NULL, 0) >= 0;
1848 /* Note if the server supports DSN */
1849 smtp_use_dsn = esmtp
1850 && pcre_exec(regex_DSN, NULL, CS buffer, Ustrlen(CS buffer), 0,
1851 PCRE_EOPT, NULL, 0) >= 0;
1852 DEBUG(D_transport) debug_printf("use_dsn=%d\n", smtp_use_dsn);
1854 /* Note if the response to EHLO specifies support for the AUTH extension.
1855 If it has, check that this host is one we want to authenticate to, and do
1856 the business. The host name and address must be available when the
1857 authenticator's client driver is running. */
1859 switch (yield = smtp_auth(buffer, sizeof(buffer), addrlist, host,
1860 ob, esmtp, &inblock, &outblock))
1862 default: goto SEND_QUIT;
1864 case FAIL_SEND: goto SEND_FAILED;
1865 case FAIL: goto RESPONSE_FAILED;
1869 /* The setting up of the SMTP call is now complete. Any subsequent errors are
1870 message-specific. */
1874 #ifdef EXPERIMENTAL_INTERNATIONAL
1875 /* If this is an international message we need the host to speak SMTPUTF8 */
1876 if (addrlist->p.utf8 && !utf8_offered)
1878 errno = ERRNO_UTF8_FWD;
1879 goto RESPONSE_FAILED;
1883 /* If there is a filter command specified for this transport, we can now
1884 set it up. This cannot be done until the identify of the host is known. */
1886 if (tblock->filter_command != NULL)
1890 sprintf(CS buffer, "%.50s transport", tblock->name);
1891 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
1892 TRUE, DEFER, addrlist, buffer, NULL);
1893 transport_filter_timeout = tblock->filter_timeout;
1895 /* On failure, copy the error to all addresses, abandon the SMTP call, and
1900 set_errno(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
1908 /* For messages that have more than the maximum number of envelope recipients,
1909 we want to send several transactions down the same SMTP connection. (See
1910 comments in deliver.c as to how this reconciles, heuristically, with
1911 remote_max_parallel.) This optimization was added to Exim after the following
1912 code was already working. The simplest way to put it in without disturbing the
1913 code was to use a goto to jump back to this point when there is another
1914 transaction to handle. */
1917 sync_addr = first_addr;
1921 completed_address = FALSE;
1924 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
1925 qualification, send it, adding something to the message size to allow for
1926 imprecision and things that get added en route. Exim keeps the number of lines
1927 in a message, so we can give an accurate value for the original message, but we
1928 need some additional to handle added headers. (Double "." characters don't get
1929 included in the count.) */
1936 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
1940 #ifndef DISABLE_PRDR
1941 prdr_active = FALSE;
1944 for (addr = first_addr; addr; addr = addr->next)
1945 if (addr->transport_return == PENDING_DEFER)
1947 for (addr = addr->next; addr; addr = addr->next)
1948 if (addr->transport_return == PENDING_DEFER)
1949 { /* at least two recipients to send */
1951 sprintf(CS p, " PRDR"); p += 5;
1959 #ifdef EXPERIMENTAL_INTERNATIONAL
1960 if (addrlist->p.utf8)
1961 sprintf(CS p, " SMTPUTF8"), p += 9;
1964 /* check if all addresses have lasthop flag */
1965 /* do not send RET and ENVID if true */
1966 for (dsn_all_lasthop = TRUE, addr = first_addr;
1967 address_count < max_rcpt && addr != NULL;
1969 if ((addr->dsn_flags & rf_dsnlasthop) != 1)
1971 dsn_all_lasthop = FALSE;
1975 /* Add any DSN flags to the mail command */
1977 if (smtp_use_dsn && !dsn_all_lasthop)
1979 if (dsn_ret == dsn_ret_hdrs)
1981 Ustrcpy(p, " RET=HDRS");
1984 else if (dsn_ret == dsn_ret_full)
1986 Ustrcpy(p, " RET=FULL");
1989 if (dsn_envid != NULL)
1991 string_format(p, sizeof(buffer) - (p-buffer), " ENVID=%s", dsn_envid);
1996 /* If an authenticated_sender override has been specified for this transport
1997 instance, expand it. If the expansion is forced to fail, and there was already
1998 an authenticated_sender for this message, the original value will be used.
1999 Other expansion failures are serious. An empty result is ignored, but there is
2000 otherwise no check - this feature is expected to be used with LMTP and other
2001 cases where non-standard addresses (e.g. without domains) might be required. */
2003 if (smtp_mail_auth_str(p, sizeof(buffer) - (p-buffer), addrlist, ob))
2009 /* From here until we send the DATA command, we can make use of PIPELINING
2010 if the server host supports it. The code has to be able to check the responses
2011 at any point, for when the buffer fills up, so we write it totally generally.
2012 When PIPELINING is off, each command written reports that it has flushed the
2015 pending_MAIL = TRUE; /* The block starts with MAIL */
2017 rc = smtp_write_command(&outblock, smtp_use_pipelining,
2018 "MAIL FROM:<%s>%s\r\n", return_path, buffer);
2019 mail_command = string_copy(big_buffer); /* Save for later error message */
2023 case -1: /* Transmission error */
2026 case +1: /* Block was sent */
2027 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2028 ob->command_timeout))
2030 if (errno == 0 && buffer[0] == '4')
2032 errno = ERRNO_MAIL4XX;
2033 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2035 goto RESPONSE_FAILED;
2037 pending_MAIL = FALSE;
2041 /* Pass over all the relevant recipient addresses for this host, which are the
2042 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
2043 several before we have to read the responses for those seen so far. This
2044 checking is done by a subroutine because it also needs to be done at the end.
2045 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
2046 the next one if not all are sent.
2048 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
2049 last address because we want to abort if any recipients have any kind of
2050 problem, temporary or permanent. We know that all recipient addresses will have
2051 the PENDING_DEFER status, because only one attempt is ever made, and we know
2052 that max_rcpt will be large, so all addresses will be done at once. */
2054 for (addr = first_addr;
2055 address_count < max_rcpt && addr != NULL;
2061 addr->dsn_aware = smtp_use_dsn ? dsn_support_yes : dsn_support_no;
2063 if (addr->transport_return != PENDING_DEFER) continue;
2066 no_flush = smtp_use_pipelining && (!mua_wrapper || addr->next != NULL);
2068 /* Add any DSN flags to the rcpt command and add to the sent string */
2073 if (smtp_use_dsn && (addr->dsn_flags & rf_dsnlasthop) != 1)
2075 if ((addr->dsn_flags & rf_dsnflags) != 0)
2079 Ustrcpy(p, " NOTIFY=");
2081 for (i = 0; i < 4; i++)
2082 if ((addr->dsn_flags & rf_list[i]) != 0)
2084 if (!first) *p++ = ',';
2086 Ustrcpy(p, rf_names[i]);
2091 if (addr->dsn_orcpt != NULL)
2093 string_format(p, sizeof(buffer) - (p-buffer), " ORCPT=%s",
2099 /* Now send the RCPT command, and process outstanding responses when
2100 necessary. After a timeout on RCPT, we just end the function, leaving the
2101 yield as OK, because this error can often mean that there is a problem with
2102 just one address, so we don't want to delay the host. */
2104 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s%s\r\n",
2105 transport_rcpt_address(addr, tblock->rcpt_include_affixes), igquotstr, buffer);
2107 if (count < 0) goto SEND_FAILED;
2110 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
2111 &sync_addr, host, count, ob->address_retry_include_sender,
2112 pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
2115 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2116 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2119 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2120 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2121 case 0: /* No 2xx or 5xx, but no probs */
2124 case -1: goto END_OFF; /* Timeout on RCPT */
2125 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
2127 pending_MAIL = FALSE; /* Dealt with MAIL */
2129 } /* Loop for next address */
2131 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
2132 permanently or temporarily. We should have flushed and synced after the last
2137 address_item *badaddr;
2138 for (badaddr = first_addr; badaddr; badaddr = badaddr->next)
2139 if (badaddr->transport_return != PENDING_OK)
2141 /*XXX could we find a better errno than 0 here? */
2142 set_errno(addrlist, 0, badaddr->message, FAIL,
2143 testflag(badaddr, af_pass_message), NULL);
2149 /* If ok is TRUE, we know we have got at least one good recipient, and must now
2150 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
2151 have a good recipient buffered up if we are pipelining. We don't want to waste
2152 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
2153 are pipelining. The responses are all handled by sync_responses(). */
2155 if (ok || (smtp_use_pipelining && !mua_wrapper))
2157 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
2158 if (count < 0) goto SEND_FAILED;
2159 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
2160 host, count, ob->address_retry_include_sender, pending_MAIL,
2161 ok? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
2163 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2164 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2167 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2168 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2169 case 0: break; /* No 2xx or 5xx, but no probs */
2171 case -1: goto END_OFF; /* Timeout on RCPT */
2172 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2176 /* Save the first address of the next batch. */
2180 /* If there were no good recipients (but otherwise there have been no
2181 problems), just set ok TRUE, since we have handled address-specific errors
2182 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
2183 for handling the SMTP dot-handling protocol, flagging to apply to headers as
2184 well as body. Set the appropriate timeout value to be used for each chunk.
2185 (Haven't been able to make it work using select() for writing yet.) */
2187 if (!ok) ok = TRUE; else
2189 sigalrm_seen = FALSE;
2190 transport_write_timeout = ob->data_timeout;
2191 smtp_command = US"sending data block"; /* For error messages */
2192 DEBUG(D_transport|D_v)
2193 debug_printf(" SMTP>> writing message and terminating \".\"\n");
2194 transport_count = 0;
2196 #ifndef DISABLE_DKIM
2197 ok = dkim_transport_write_message(addrlist, inblock.sock,
2198 topt_use_crlf | topt_end_dot | topt_escape_headers |
2199 (tblock->body_only? topt_no_headers : 0) |
2200 (tblock->headers_only? topt_no_body : 0) |
2201 (tblock->return_path_add? topt_add_return_path : 0) |
2202 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
2203 (tblock->envelope_to_add? topt_add_envelope_to : 0),
2204 0, /* No size limit */
2205 tblock->add_headers, tblock->remove_headers,
2206 US".", US"..", /* Escaping strings */
2207 tblock->rewrite_rules, tblock->rewrite_existflags,
2208 ob->dkim_private_key, ob->dkim_domain, ob->dkim_selector,
2209 ob->dkim_canon, ob->dkim_strict, ob->dkim_sign_headers
2212 ok = transport_write_message(addrlist, inblock.sock,
2213 topt_use_crlf | topt_end_dot | topt_escape_headers |
2214 (tblock->body_only? topt_no_headers : 0) |
2215 (tblock->headers_only? topt_no_body : 0) |
2216 (tblock->return_path_add? topt_add_return_path : 0) |
2217 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
2218 (tblock->envelope_to_add? topt_add_envelope_to : 0),
2219 0, /* No size limit */
2220 tblock->add_headers, tblock->remove_headers,
2221 US".", US"..", /* Escaping strings */
2222 tblock->rewrite_rules, tblock->rewrite_existflags);
2225 /* transport_write_message() uses write() because it is called from other
2226 places to write to non-sockets. This means that under some OS (e.g. Solaris)
2227 it can exit with "Broken pipe" as its error. This really means that the
2228 socket got closed at the far end. */
2230 transport_write_timeout = 0; /* for subsequent transports */
2232 /* Failure can either be some kind of I/O disaster (including timeout),
2233 or the failure of a transport filter or the expansion of added headers. */
2237 buffer[0] = 0; /* There hasn't been a response */
2238 goto RESPONSE_FAILED;
2241 /* We used to send the terminating "." explicitly here, but because of
2242 buffering effects at both ends of TCP/IP connections, you don't gain
2243 anything by keeping it separate, so it might as well go in the final
2244 data buffer for efficiency. This is now done by setting the topt_end_dot
2247 smtp_command = US"end of data";
2249 #ifndef DISABLE_PRDR
2250 /* For PRDR we optionally get a partial-responses warning
2251 * followed by the individual responses, before going on with
2252 * the overall response. If we don't get the warning then deal
2253 * with per non-PRDR. */
2256 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '3',
2258 if (!ok && errno == 0)
2261 case '2': prdr_active = FALSE;
2264 case '4': errno = ERRNO_DATA4XX;
2265 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2272 /* For non-PRDR SMTP, we now read a single response that applies to the
2273 whole message. If it is OK, then all the addresses have been delivered. */
2277 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2279 if (!ok && errno == 0 && buffer[0] == '4')
2281 errno = ERRNO_DATA4XX;
2282 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2286 /* For LMTP, we get back a response for every RCPT command that we sent;
2287 some may be accepted and some rejected. For those that get a response, their
2288 status is fixed; any that are accepted have been handed over, even if later
2289 responses crash - at least, that's how I read RFC 2033.
2291 If all went well, mark the recipient addresses as completed, record which
2292 host/IPaddress they were delivered to, and cut out RSET when sending another
2293 message down the same channel. Write the completed addresses to the journal
2294 now so that they are recorded in case there is a crash of hardware or
2295 software before the spool gets updated. Also record the final SMTP
2296 confirmation if needed (for SMTP only). */
2301 int delivery_time = (int)(time(NULL) - start_delivery_time);
2303 uschar *conf = NULL;
2306 /* Set up confirmation if needed - applies only to SMTP */
2309 #ifndef EXPERIMENTAL_EVENT
2310 (log_extra_selector & LX_smtp_confirmation) != 0 &&
2315 const uschar *s = string_printing(buffer);
2316 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
2317 conf = (s == buffer)? (uschar *)string_copy(s) : US s;
2320 /* Process all transported addresses - for LMTP or PRDR, read a status for
2323 for (addr = addrlist; addr != first_addr; addr = addr->next)
2325 if (addr->transport_return != PENDING_OK) continue;
2327 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
2328 remaining addresses. Otherwise, it's a return code for just the one
2329 address. For temporary errors, add a retry item for the address so that
2330 it doesn't get tried again too soon. */
2332 #ifndef DISABLE_PRDR
2333 if (lmtp || prdr_active)
2338 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2341 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
2342 addr->message = string_sprintf(
2343 #ifndef DISABLE_PRDR
2344 "%s error after %s: %s", prdr_active ? "PRDR":"LMTP",
2346 "LMTP error after %s: %s",
2348 big_buffer, string_printing(buffer));
2349 setflag(addr, af_pass_message); /* Allow message to go to user */
2350 if (buffer[0] == '5')
2351 addr->transport_return = FAIL;
2354 errno = ERRNO_DATA4XX;
2355 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2356 addr->transport_return = DEFER;
2357 #ifndef DISABLE_PRDR
2360 retry_add_item(addr, addr->address_retry_key, 0);
2364 completed_address = TRUE; /* NOW we can set this flag */
2365 if ((log_extra_selector & LX_smtp_confirmation) != 0)
2367 const uschar *s = string_printing(buffer);
2368 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
2369 conf = (s == buffer)? (uschar *)string_copy(s) : US s;
2373 /* SMTP, or success return from LMTP for this address. Pass back the
2374 actual host that was used. */
2376 addr->transport_return = OK;
2377 addr->more_errno = delivery_time;
2378 addr->host_used = host;
2379 addr->special_action = flag;
2380 addr->message = conf;
2381 #ifndef DISABLE_PRDR
2382 if (prdr_active) addr->flags |= af_prdr_used;
2386 #ifndef DISABLE_PRDR
2390 /* Update the journal. For homonymic addresses, use the base address plus
2391 the transport name. See lots of comments in deliver.c about the reasons
2392 for the complications when homonyms are involved. Just carry on after
2393 write error, as it may prove possible to update the spool file later. */
2395 if (testflag(addr, af_homonym))
2396 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2398 sprintf(CS buffer, "%.500s\n", addr->unique);
2400 DEBUG(D_deliver) debug_printf("journalling %s", buffer);
2401 len = Ustrlen(CS buffer);
2402 if (write(journal_fd, buffer, len) != len)
2403 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2404 "%s: %s", buffer, strerror(errno));
2408 #ifndef DISABLE_PRDR
2411 /* PRDR - get the final, overall response. For any non-success
2412 upgrade all the address statuses. */
2413 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2417 if(errno == 0 && buffer[0] == '4')
2419 errno = ERRNO_DATA4XX;
2420 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2422 for (addr = addrlist; addr != first_addr; addr = addr->next)
2423 if (buffer[0] == '5' || addr->transport_return == OK)
2424 addr->transport_return = PENDING_OK; /* allow set_errno action */
2425 goto RESPONSE_FAILED;
2428 /* Update the journal, or setup retry. */
2429 for (addr = addrlist; addr != first_addr; addr = addr->next)
2430 if (addr->transport_return == OK)
2432 if (testflag(addr, af_homonym))
2433 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2435 sprintf(CS buffer, "%.500s\n", addr->unique);
2437 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s", buffer);
2438 len = Ustrlen(CS buffer);
2439 if (write(journal_fd, buffer, len) != len)
2440 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2441 "%s: %s", buffer, strerror(errno));
2443 else if (addr->transport_return == DEFER)
2444 retry_add_item(addr, addr->address_retry_key, -2);
2448 /* Ensure the journal file is pushed out to disk. */
2450 if (EXIMfsync(journal_fd) < 0)
2451 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
2457 /* Handle general (not specific to one address) failures here. The value of ok
2458 is used to skip over this code on the falling through case. A timeout causes a
2459 deferral. Other errors may defer or fail according to the response code, and
2460 may set up a special errno value, e.g. after connection chopped, which is
2461 assumed if errno == 0 and there is no text in the buffer. If control reaches
2462 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
2463 the problem is not related to this specific message. */
2472 send_quit = check_response(host, &save_errno, addrlist->more_errno,
2473 buffer, &code, &message, &pass_message);
2479 message = US string_sprintf("send() to %s [%s] failed: %s",
2480 host->name, host->address, strerror(save_errno));
2484 /* This label is jumped to directly when a TLS negotiation has failed,
2485 or was not done for a host for which it is required. Values will be set
2486 in message and save_errno, and setting_up will always be true. Treat as
2487 a temporary error. */
2494 /* If the failure happened while setting up the call, see if the failure was
2495 a 5xx response (this will either be on connection, or following HELO - a 5xx
2496 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
2497 never going to accept them. For other errors during setting up (timeouts or
2498 whatever), defer all addresses, and yield DEFER, so that the host is not
2499 tried again for a while. */
2502 ok = FALSE; /* For when reached by GOTO */
2507 set_errno(addrlist, save_errno, message, FAIL, pass_message, host);
2510 set_errno(addrlist, save_errno, message, DEFER, pass_message, host);
2515 /* We want to handle timeouts after MAIL or "." and loss of connection after
2516 "." specially. They can indicate a problem with the sender address or with
2517 the contents of the message rather than a real error on the connection. These
2518 cases are treated in the same way as a 4xx response. This next bit of code
2519 does the classification. */
2530 message_error = TRUE;
2534 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
2535 Ustrncmp(smtp_command,"end ",4) == 0;
2538 case ERRNO_SMTPCLOSED:
2539 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
2543 message_error = FALSE;
2547 /* Handle the cases that are treated as message errors. These are:
2549 (a) negative response or timeout after MAIL
2550 (b) negative response after DATA
2551 (c) negative response or timeout or dropped connection after "."
2553 It won't be a negative response or timeout after RCPT, as that is dealt
2554 with separately above. The action in all cases is to set an appropriate
2555 error code for all the addresses, but to leave yield set to OK because the
2556 host itself has not failed. Of course, it might in practice have failed
2557 when we've had a timeout, but if so, we'll discover that at the next
2558 delivery attempt. For a temporary error, set the message_defer flag, and
2559 write to the logs for information if this is not the last host. The error
2560 for the last host will be logged as part of the address's log line. */
2564 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
2565 set_errno(addrlist, save_errno, message, (code == '5')? FAIL : DEFER,
2566 pass_message, host);
2568 /* If there's an errno, the message contains just the identity of
2571 if (code != '5') /* Anything other than 5 is treated as temporary */
2574 message = US string_sprintf("%s: %s", message, strerror(save_errno));
2575 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
2576 msglog_line(host, message);
2577 *message_defer = TRUE;
2581 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
2582 ".", or some other transportation error. We defer all addresses and yield
2583 DEFER, except for the case of failed add_headers expansion, or a transport
2584 filter failure, when the yield should be ERROR, to stop it trying other
2589 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
2590 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
2591 set_errno(addrlist, save_errno, message, DEFER, pass_message, host);
2597 /* If all has gone well, send_quit will be set TRUE, implying we can end the
2598 SMTP session tidily. However, if there were too many addresses to send in one
2599 message (indicated by first_addr being non-NULL) we want to carry on with the
2600 rest of them. Also, it is desirable to send more than one message down the SMTP
2601 connection if there are several waiting, provided we haven't already sent so
2602 many as to hit the configured limit. The function transport_check_waiting looks
2603 for a waiting message and returns its id. Then transport_pass_socket tries to
2604 set up a continued delivery by passing the socket on to another process. The
2605 variable send_rset is FALSE if a message has just been successfully transfered.
2607 If we are already sending down a continued channel, there may be further
2608 addresses not yet delivered that are aimed at the same host, but which have not
2609 been passed in this run of the transport. In this case, continue_more will be
2610 true, and all we should do is send RSET if necessary, and return, leaving the
2613 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
2614 do not want to continue with other messages down the same channel, because that
2615 can lead to looping between two or more messages, all with the same,
2616 temporarily failing address(es). [The retry information isn't updated yet, so
2617 new processes keep on trying.] We probably also don't want to try more of this
2618 message's addresses either.
2620 If we have started a TLS session, we have to end it before passing the
2621 connection to a new process. However, not all servers can handle this (Exim
2622 can), so we do not pass such a connection on if the host matches
2623 hosts_nopass_tls. */
2626 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
2627 "yield=%d first_address is %sNULL\n", ok, send_quit, send_rset,
2628 continue_more, yield, (first_addr == NULL)? "":"not ");
2630 if (completed_address && ok && send_quit)
2633 smtp_compare_t t_compare;
2635 t_compare.tblock = tblock;
2636 t_compare.current_sender_address = sender_address;
2638 if ( first_addr != NULL
2640 || ( ( tls_out.active < 0
2641 || verify_check_given_host(&ob->hosts_nopass_tls, host) != OK
2644 transport_check_waiting(tblock->name, host->name,
2645 tblock->connection_max_messages, new_message_id, &more,
2646 (oicf)smtp_are_same_identities, (void*)&t_compare)
2654 if (! (ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
2656 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
2657 host->address, strerror(save_errno));
2660 else if (! (ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2661 ob->command_timeout)))
2664 send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
2668 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
2669 host->name, host->address, msg);
2674 /* Either RSET was not needed, or it succeeded */
2678 if (first_addr != NULL) /* More addresses still to be sent */
2679 { /* in this run of the transport */
2680 continue_sequence++; /* Causes * in logging */
2683 if (continue_more) return yield; /* More addresses for another run */
2685 /* Pass the socket to a new Exim process. Before doing so, we must shut
2686 down TLS. Not all MTAs allow for the continuation of the SMTP session
2687 when TLS is shut down. We test for this by sending a new EHLO. If we
2688 don't get a good response, we don't attempt to pass the socket on. */
2691 if (tls_out.active >= 0)
2693 tls_close(FALSE, TRUE);
2697 ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
2698 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2699 ob->command_timeout);
2703 /* If the socket is successfully passed, we musn't send QUIT (or
2704 indeed anything!) from here. */
2706 if (ok && transport_pass_socket(tblock->name, host->name, host->address,
2707 new_message_id, inblock.sock))
2713 /* If RSET failed and there are addresses left, they get deferred. */
2715 else set_errno(first_addr, errno, msg, DEFER, FALSE, host);
2719 /* End off tidily with QUIT unless the connection has died or the socket has
2720 been passed to another process. There has been discussion on the net about what
2721 to do after sending QUIT. The wording of the RFC suggests that it is necessary
2722 to wait for a response, but on the other hand, there isn't anything one can do
2723 with an error response, other than log it. Exim used to do that. However,
2724 further discussion suggested that it is positively advantageous not to wait for
2725 the response, but to close the session immediately. This is supposed to move
2726 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
2727 load from the server. (Hosts that are both servers and clients may not see much
2728 difference, of course.) Further discussion indicated that this was safe to do
2729 on Unix systems which have decent implementations of TCP/IP that leave the
2730 connection around for a while (TIME_WAIT) after the application has gone away.
2731 This enables the response sent by the server to be properly ACKed rather than
2732 timed out, as can happen on broken TCP/IP implementations on other OS.
2734 This change is being made on 31-Jul-98. After over a year of trouble-free
2735 operation, the old commented-out code was removed on 17-Sep-99. */
2738 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2743 tls_close(FALSE, TRUE);
2746 /* Close the socket, and return the appropriate value, first setting
2747 works because the NULL setting is passed back to the calling process, and
2748 remote_max_parallel is forced to 1 when delivering over an existing connection,
2750 If all went well and continue_more is set, we shouldn't actually get here if
2751 there are further addresses, as the return above will be taken. However,
2752 writing RSET might have failed, or there may be other addresses whose hosts are
2753 specified in the transports, and therefore not visible at top level, in which
2754 case continue_more won't get set. */
2756 (void)close(inblock.sock);
2758 #ifdef EXPERIMENTAL_EVENT
2759 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
2762 continue_transport = NULL;
2763 continue_hostname = NULL;
2770 /*************************************************
2771 * Closedown entry point *
2772 *************************************************/
2774 /* This function is called when exim is passed an open smtp channel
2775 from another incarnation, but the message which it has been asked
2776 to deliver no longer exists. The channel is on stdin.
2778 We might do fancy things like looking for another message to send down
2779 the channel, but if the one we sought has gone, it has probably been
2780 delivered by some other process that itself will seek further messages,
2781 so just close down our connection.
2783 Argument: pointer to the transport instance block
2788 smtp_transport_closedown(transport_instance *tblock)
2790 smtp_transport_options_block *ob =
2791 (smtp_transport_options_block *)(tblock->options_block);
2792 smtp_inblock inblock;
2793 smtp_outblock outblock;
2795 uschar inbuffer[4096];
2796 uschar outbuffer[16];
2798 inblock.sock = fileno(stdin);
2799 inblock.buffer = inbuffer;
2800 inblock.buffersize = sizeof(inbuffer);
2801 inblock.ptr = inbuffer;
2802 inblock.ptrend = inbuffer;
2804 outblock.sock = inblock.sock;
2805 outblock.buffersize = sizeof(outbuffer);
2806 outblock.buffer = outbuffer;
2807 outblock.ptr = outbuffer;
2808 outblock.cmd_count = 0;
2809 outblock.authenticating = FALSE;
2811 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2812 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2813 ob->command_timeout);
2814 (void)close(inblock.sock);
2819 /*************************************************
2820 * Prepare addresses for delivery *
2821 *************************************************/
2823 /* This function is called to flush out error settings from previous delivery
2824 attempts to other hosts. It also records whether we got here via an MX record
2825 or not in the more_errno field of the address. We are interested only in
2826 addresses that are still marked DEFER - others may have got delivered to a
2827 previously considered IP address. Set their status to PENDING_DEFER to indicate
2828 which ones are relevant this time.
2831 addrlist the list of addresses
2832 host the host we are delivering to
2834 Returns: the first address for this delivery
2837 static address_item *
2838 prepare_addresses(address_item *addrlist, host_item *host)
2840 address_item *first_addr = NULL;
2842 for (addr = addrlist; addr != NULL; addr = addr->next)
2843 if (addr->transport_return == DEFER)
2845 if (first_addr == NULL) first_addr = addr;
2846 addr->transport_return = PENDING_DEFER;
2847 addr->basic_errno = 0;
2848 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
2849 addr->message = NULL;
2851 addr->cipher = NULL;
2852 addr->ourcert = NULL;
2853 addr->peercert = NULL;
2854 addr->peerdn = NULL;
2855 addr->ocsp = OCSP_NOT_REQ;
2863 /*************************************************
2864 * Main entry point *
2865 *************************************************/
2867 /* See local README for interface details. As this is a remote transport, it is
2868 given a chain of addresses to be delivered in one connection, if possible. It
2869 always returns TRUE, indicating that each address has its own independent
2870 status set, except if there is a setting up problem, in which case it returns
2874 smtp_transport_entry(
2875 transport_instance *tblock, /* data for this instantiation */
2876 address_item *addrlist) /* addresses we are working on */
2880 int hosts_defer = 0;
2882 int hosts_looked_up = 0;
2883 int hosts_retry = 0;
2884 int hosts_serial = 0;
2885 int hosts_total = 0;
2886 int total_hosts_tried = 0;
2888 BOOL expired = TRUE;
2889 BOOL continuing = continue_hostname != NULL;
2890 uschar *expanded_hosts = NULL;
2892 uschar *tid = string_sprintf("%s transport", tblock->name);
2893 smtp_transport_options_block *ob =
2894 (smtp_transport_options_block *)(tblock->options_block);
2895 host_item *hostlist = addrlist->host_list;
2896 host_item *host = NULL;
2900 debug_printf("%s transport entered\n", tblock->name);
2901 for (addr = addrlist; addr != NULL; addr = addr->next)
2902 debug_printf(" %s\n", addr->address);
2903 if (continuing) debug_printf("already connected to %s [%s]\n",
2904 continue_hostname, continue_host_address);
2907 /* Set the flag requesting that these hosts be added to the waiting
2908 database if the delivery fails temporarily or if we are running with
2909 queue_smtp or a 2-stage queue run. This gets unset for certain
2910 kinds of error, typically those that are specific to the message. */
2912 update_waiting = TRUE;
2914 /* If a host list is not defined for the addresses - they must all have the
2915 same one in order to be passed to a single transport - or if the transport has
2916 a host list with hosts_override set, use the host list supplied with the
2917 transport. It is an error for this not to exist. */
2919 if (hostlist == NULL || (ob->hosts_override && ob->hosts != NULL))
2921 if (ob->hosts == NULL)
2923 addrlist->message = string_sprintf("%s transport called with no hosts set",
2925 addrlist->transport_return = PANIC;
2926 return FALSE; /* Only top address has status */
2929 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
2932 /* If the transport's host list contains no '$' characters, and we are not
2933 randomizing, it is fixed and therefore a chain of hosts can be built once
2934 and for all, and remembered for subsequent use by other calls to this
2935 transport. If, on the other hand, the host list does contain '$', or we are
2936 randomizing its order, we have to rebuild it each time. In the fixed case,
2937 as the hosts string will never be used again, it doesn't matter that we
2938 replace all the : characters with zeros. */
2940 if (ob->hostlist == NULL)
2942 uschar *s = ob->hosts;
2944 if (Ustrchr(s, '$') != NULL)
2946 if (!(expanded_hosts = expand_string(s)))
2948 addrlist->message = string_sprintf("failed to expand list of hosts "
2949 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
2950 addrlist->transport_return = search_find_defer? DEFER : PANIC;
2951 return FALSE; /* Only top address has status */
2953 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
2954 "\"%s\"\n", s, expanded_hosts);
2958 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
2960 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
2962 /* Check that the expansion yielded something useful. */
2963 if (hostlist == NULL)
2966 string_sprintf("%s transport has empty hosts setting", tblock->name);
2967 addrlist->transport_return = PANIC;
2968 return FALSE; /* Only top address has status */
2971 /* If there was no expansion of hosts, save the host list for
2974 if (!expanded_hosts) ob->hostlist = hostlist;
2977 /* This is not the first time this transport has been run in this delivery;
2978 the host list was built previously. */
2981 hostlist = ob->hostlist;
2984 /* The host list was supplied with the address. If hosts_randomize is set, we
2985 must sort it into a random order if it did not come from MX records and has not
2986 already been randomized (but don't bother if continuing down an existing
2989 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continuing)
2991 host_item *newlist = NULL;
2992 while (hostlist != NULL)
2994 host_item *h = hostlist;
2995 hostlist = hostlist->next;
2997 h->sort_key = random_number(100);
2999 if (newlist == NULL)
3004 else if (h->sort_key < newlist->sort_key)
3011 host_item *hh = newlist;
3012 while (hh->next != NULL)
3014 if (h->sort_key < hh->next->sort_key) break;
3022 hostlist = addrlist->host_list = newlist;
3025 /* Sort out the default port. */
3027 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
3029 /* For each host-plus-IP-address on the list:
3031 . If this is a continued delivery and the host isn't the one with the
3032 current connection, skip.
3034 . If the status is unusable (i.e. previously failed or retry checked), skip.
3036 . If no IP address set, get the address, either by turning the name into
3037 an address, calling gethostbyname if gethostbyname is on, or by calling
3038 the DNS. The DNS may yield multiple addresses, in which case insert the
3039 extra ones into the list.
3041 . Get the retry data if not previously obtained for this address and set the
3042 field which remembers the state of this address. Skip if the retry time is
3043 not reached. If not, remember whether retry data was found. The retry string
3044 contains both the name and the IP address.
3046 . Scan the list of addresses and mark those whose status is DEFER as
3047 PENDING_DEFER. These are the only ones that will be processed in this cycle
3050 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
3051 Some addresses may be successfully delivered, others may fail, and yet
3052 others may get temporary errors and so get marked DEFER.
3054 . The return from the delivery attempt is OK if a connection was made and a
3055 valid SMTP dialogue was completed. Otherwise it is DEFER.
3057 . If OK, add a "remove" retry item for this host/IPaddress, if any.
3059 . If fail to connect, or other defer state, add a retry item.
3061 . If there are any addresses whose status is still DEFER, carry on to the
3062 next host/IPaddress, unless we have tried the number of hosts given
3063 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
3064 there is some fancy logic for hosts_max_try that means its limit can be
3065 overstepped in some circumstances.
3067 If we get to the end of the list, all hosts have deferred at least one address,
3068 or not reached their retry times. If delay_after_cutoff is unset, it requests a
3069 delivery attempt to those hosts whose last try was before the arrival time of
3070 the current message. To cope with this, we have to go round the loop a second
3071 time. After that, set the status and error data for any addresses that haven't
3072 had it set already. */
3074 for (cutoff_retry = 0; expired &&
3075 cutoff_retry < ((ob->delay_after_cutoff)? 1 : 2);
3078 host_item *nexthost = NULL;
3079 int unexpired_hosts_tried = 0;
3081 for (host = hostlist;
3083 unexpired_hosts_tried < ob->hosts_max_try &&
3084 total_hosts_tried < ob->hosts_max_try_hardlimit;
3090 BOOL serialized = FALSE;
3091 BOOL host_is_expired = FALSE;
3092 BOOL message_defer = FALSE;
3093 BOOL ifchanges = FALSE;
3094 BOOL some_deferred = FALSE;
3095 address_item *first_addr = NULL;
3096 uschar *interface = NULL;
3097 uschar *retry_host_key = NULL;
3098 uschar *retry_message_key = NULL;
3099 uschar *serialize_key = NULL;
3101 /* Default next host is next host. :-) But this can vary if the
3102 hosts_max_try limit is hit (see below). It may also be reset if a host
3103 address is looked up here (in case the host was multihomed). */
3105 nexthost = host->next;
3107 /* If the address hasn't yet been obtained from the host name, look it up
3108 now, unless the host is already marked as unusable. If it is marked as
3109 unusable, it means that the router was unable to find its IP address (in
3110 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
3111 the lookup failed last time. We don't get this far if *all* MX records
3112 point to non-existent hosts; that is treated as a hard error.
3114 We can just skip this host entirely. When the hosts came from the router,
3115 the address will timeout based on the other host(s); when the address is
3116 looked up below, there is an explicit retry record added.
3118 Note that we mustn't skip unusable hosts if the address is not unset; they
3119 may be needed as expired hosts on the 2nd time round the cutoff loop. */
3121 if (host->address == NULL)
3123 int new_port, flags;
3126 if (host->status >= hstatus_unusable)
3128 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
3133 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
3135 /* The host name is permitted to have an attached port. Find it, and
3136 strip it from the name. Just remember it for now. */
3138 new_port = host_item_get_port(host);
3140 /* Count hosts looked up */
3144 /* Find by name if so configured, or if it's an IP address. We don't
3145 just copy the IP address, because we need the test-for-local to happen. */
3147 flags = HOST_FIND_BY_A;
3148 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
3149 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
3151 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
3152 rc = host_find_byname(host, NULL, flags, NULL, TRUE);
3154 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
3155 ob->dnssec_request_domains, ob->dnssec_require_domains,
3158 /* Update the host (and any additional blocks, resulting from
3159 multihoming) with a host-specific port, if any. */
3161 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
3163 /* Failure to find the host at this time (usually DNS temporary failure)
3164 is really a kind of routing failure rather than a transport failure.
3165 Therefore we add a retry item of the routing kind, not to stop us trying
3166 to look this name up here again, but to ensure the address gets timed
3167 out if the failures go on long enough. A complete failure at this point
3168 commonly points to a configuration error, but the best action is still
3169 to carry on for the next host. */
3171 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
3173 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
3175 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
3176 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
3177 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
3178 host->status = hstatus_unusable;
3180 for (addr = addrlist; addr != NULL; addr = addr->next)
3182 if (addr->transport_return != DEFER) continue;
3183 addr->basic_errno = ERRNO_UNKNOWNHOST;
3185 string_sprintf("failed to lookup IP address for %s", host->name);
3190 /* If the host is actually the local host, we may have a problem, or
3191 there may be some cunning configuration going on. In the problem case,
3192 log things and give up. The default transport status is already DEFER. */
3194 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
3196 for (addr = addrlist; addr != NULL; addr = addr->next)
3198 addr->basic_errno = 0;
3199 addr->message = string_sprintf("%s transport found host %s to be "
3200 "local", tblock->name, host->name);
3204 } /* End of block for IP address lookup */
3206 /* If this is a continued delivery, we are interested only in the host
3207 which matches the name of the existing open channel. The check is put
3208 here after the local host lookup, in case the name gets expanded as a
3209 result of the lookup. Set expired FALSE, to save the outer loop executing
3212 if (continuing && (Ustrcmp(continue_hostname, host->name) != 0 ||
3213 Ustrcmp(continue_host_address, host->address) != 0))
3216 continue; /* With next host */
3219 /* Reset the default next host in case a multihomed host whose addresses
3220 are not looked up till just above added to the host list. */
3222 nexthost = host->next;
3224 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
3225 domain is in queue_smtp_domains, we don't actually want to attempt any
3226 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
3227 there is a lookup defer in queue_smtp_domains, proceed as if the domain
3228 were not in it. We don't want to hold up all SMTP deliveries! Except when
3229 doing a two-stage queue run, don't do this if forcing. */
3231 if ((!deliver_force || queue_2stage) && (queue_smtp ||
3232 match_isinlist(addrlist->domain,
3233 (const uschar **)&queue_smtp_domains, 0,
3234 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
3237 for (addr = addrlist; addr != NULL; addr = addr->next)
3239 if (addr->transport_return != DEFER) continue;
3240 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
3242 continue; /* With next host */
3245 /* Count hosts being considered - purely for an intelligent comment
3246 if none are usable. */
3250 /* Set $host and $host address now in case they are needed for the
3251 interface expansion or the serialize_hosts check; they remain set if an
3252 actual delivery happens. */
3254 deliver_host = host->name;
3255 deliver_host_address = host->address;
3256 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
3257 : host->dnssec == DS_NO ? US"no"
3260 /* Set up a string for adding to the retry key if the port number is not
3261 the standard SMTP port. A host may have its own port setting that overrides
3264 pistring = string_sprintf(":%d", (host->port == PORT_NONE)?
3266 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
3268 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
3269 string changes upon expansion, we must add it to the key that is used for
3270 retries, because connections to the same host from a different interface
3271 should be treated separately. */
3273 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET : AF_INET6;
3274 if (!smtp_get_interface(ob->interface, host_af, addrlist, &ifchanges,
3277 if (ifchanges) pistring = string_sprintf("%s/%s", pistring, interface);
3279 /* The first time round the outer loop, check the status of the host by
3280 inspecting the retry data. The second time round, we are interested only
3281 in expired hosts that haven't been tried since this message arrived. */
3283 if (cutoff_retry == 0)
3286 /* Ensure the status of the address is set by checking retry data if
3287 necessary. There may be host-specific retry data (applicable to all
3288 messages) and also data for retries of a specific message at this host.
3289 If either of these retry records are actually read, the keys used are
3290 returned to save recomputing them later. */
3292 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3293 US"retry_include_ip_address", ob->retry_include_ip_address,
3294 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3295 continue; /* with next host */
3297 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
3298 incl_ip, &retry_host_key, &retry_message_key);
3300 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
3301 (host->address == NULL)? US"" : host->address, pistring,
3302 (host->status == hstatus_usable)? "usable" :
3303 (host->status == hstatus_unusable)? "unusable" :
3304 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
3306 /* Skip this address if not usable at this time, noting if it wasn't
3307 actually expired, both locally and in the address. */
3309 switch (host->status)
3311 case hstatus_unusable:
3313 setflag(addrlist, af_retry_skipped);
3316 case hstatus_unusable_expired:
3319 case hwhy_retry: hosts_retry++; break;
3320 case hwhy_failed: hosts_fail++; break;
3321 case hwhy_deferred: hosts_defer++; break;
3324 /* If there was a retry message key, implying that previously there
3325 was a message-specific defer, we don't want to update the list of
3326 messages waiting for these hosts. */
3328 if (retry_message_key != NULL) update_waiting = FALSE;
3329 continue; /* With the next host or IP address */
3333 /* Second time round the loop: if the address is set but expired, and
3334 the message is newer than the last try, let it through. */
3338 if (host->address == NULL ||
3339 host->status != hstatus_unusable_expired ||
3340 host->last_try > received_time)
3343 debug_printf("trying expired host %s [%s]%s\n",
3344 host->name, host->address, pistring);
3345 host_is_expired = TRUE;
3348 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
3349 it remains TRUE only if all hosts are expired and none are actually tried.
3354 /* If this host is listed as one to which access must be serialized,
3355 see if another Exim process has a connection to it, and if so, skip
3356 this host. If not, update the database to record our connection to it
3357 and remember this for later deletion. Do not do any of this if we are
3358 sending the message down a pre-existing connection. */
3361 verify_check_given_host(&ob->serialize_hosts, host) == OK)
3363 serialize_key = string_sprintf("host-serialize-%s", host->name);
3364 if (!enq_start(serialize_key))
3367 debug_printf("skipping host %s because another Exim process "
3368 "is connected to it\n", host->name);
3375 /* OK, we have an IP address that is not waiting for its retry time to
3376 arrive (it might be expired) OR (second time round the loop) we have an
3377 expired host that hasn't been tried since the message arrived. Have a go
3378 at delivering the message to it. First prepare the addresses by flushing
3379 out the result of previous attempts, and finding the first address that
3380 is still to be delivered. */
3382 first_addr = prepare_addresses(addrlist, host);
3384 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
3385 message_id, host->name, host->address, addrlist->address,
3386 (addrlist->next == NULL)? "" : ", ...");
3388 set_process_info("delivering %s to %s [%s] (%s%s)",
3389 message_id, host->name, host->address, addrlist->address,
3390 (addrlist->next == NULL)? "" : ", ...");
3392 /* This is not for real; don't do the delivery. If there are
3393 any remaining hosts, list them. */
3398 set_errno(addrlist, 0, NULL, OK, FALSE, NULL);
3399 for (addr = addrlist; addr != NULL; addr = addr->next)
3401 addr->host_used = host;
3402 addr->special_action = '*';
3403 addr->message = US"delivery bypassed by -N option";
3407 debug_printf("*** delivery by %s transport bypassed by -N option\n"
3408 "*** host and remaining hosts:\n", tblock->name);
3409 for (host2 = host; host2 != NULL; host2 = host2->next)
3410 debug_printf(" %s [%s]\n", host2->name,
3411 (host2->address == NULL)? US"unset" : host2->address);
3416 /* This is for real. If the host is expired, we don't count it for
3417 hosts_max_retry. This ensures that all hosts must expire before an address
3418 is timed out, unless hosts_max_try_hardlimit (which protects against
3419 lunatic DNS configurations) is reached.
3421 If the host is not expired and we are about to hit the hosts_max_retry
3422 limit, check to see if there is a subsequent hosts with a different MX
3423 value. If so, make that the next host, and don't count this one. This is a
3424 heuristic to make sure that different MXs do get tried. With a normal kind
3425 of retry rule, they would get tried anyway when the earlier hosts were
3426 delayed, but if the domain has a "retry every time" type of rule - as is
3427 often used for the the very large ISPs, that won't happen. */
3432 /* Make a copy of the host if it is local to this invocation
3433 of the transport. */
3437 thost = store_get(sizeof(host_item));
3439 thost->name = string_copy(host->name);
3440 thost->address = string_copy(host->address);
3445 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
3449 debug_printf("hosts_max_try limit reached with this host\n");
3450 for (h = host; h != NULL; h = h->next)
3451 if (h->mx != host->mx) break;
3455 unexpired_hosts_tried--;
3456 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
3457 "and will be tried\n");
3461 /* Attempt the delivery. */
3463 total_hosts_tried++;
3464 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
3465 &message_defer, FALSE);
3468 OK => connection made, each address contains its result;
3469 message_defer is set for message-specific defers (when all
3470 recipients are marked defer)
3471 DEFER => there was a non-message-specific delivery problem;
3472 ERROR => there was a problem setting up the arguments for a filter,
3473 or there was a problem with expanding added headers
3476 /* If the result is not OK, there was a non-message-specific problem.
3477 If the result is DEFER, we need to write to the logs saying what happened
3478 for this particular host, except in the case of authentication and TLS
3479 failures, where the log has already been written. If all hosts defer a
3480 general message is written at the end. */
3482 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL &&
3483 first_addr->basic_errno != ERRNO_TLSFAILURE)
3484 write_logs(first_addr, host);
3486 #ifdef EXPERIMENTAL_EVENT
3488 deferred_event_raise(first_addr, host);
3491 /* If STARTTLS was accepted, but there was a failure in setting up the
3492 TLS session (usually a certificate screwup), and the host is not in
3493 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
3494 TLS forcibly turned off. We have to start from scratch with a new SMTP
3495 connection. That's why the retry is done from here, not from within
3496 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
3497 session, so the in-clear transmission after those errors, if permitted,
3498 happens inside smtp_deliver().] */
3502 && first_addr->basic_errno == ERRNO_TLSFAILURE
3503 && ob->tls_tempfail_tryclear
3504 && verify_check_given_host(&ob->hosts_require_tls, host) != OK
3507 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
3508 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
3509 first_addr = prepare_addresses(addrlist, host);
3510 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
3511 &message_defer, TRUE);
3512 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
3513 write_logs(first_addr, host);
3514 # ifdef EXPERIMENTAL_EVENT
3516 deferred_event_raise(first_addr, host);
3519 #endif /*SUPPORT_TLS*/
3522 /* Delivery attempt finished */
3524 rs = (rc == OK)? US"OK" : (rc == DEFER)? US"DEFER" : (rc == ERROR)?
3527 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
3528 message_id, host->name, host->address, addrlist->address,
3529 (addrlist->next == NULL)? "" : " (& others)", rs);
3531 /* Release serialization if set up */
3533 if (serialized) enq_end(serialize_key);
3535 /* If the result is DEFER, or if a host retry record is known to exist, we
3536 need to add an item to the retry chain for updating the retry database
3537 at the end of delivery. We only need to add the item to the top address,
3538 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
3539 for any other delivery attempts using the same address. (It is copied into
3540 the unusable tree at the outer level, so even if different address blocks
3541 contain the same address, it still won't get tried again.) */
3543 if (rc == DEFER || retry_host_key != NULL)
3545 int delete_flag = (rc != DEFER)? rf_delete : 0;
3546 if (retry_host_key == NULL)
3549 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3550 US"retry_include_ip_address", ob->retry_include_ip_address,
3551 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3552 incl_ip = TRUE; /* error; use most-specific retry record */
3554 retry_host_key = incl_ip ?
3555 string_sprintf("T:%S:%s%s", host->name, host->address, pistring) :
3556 string_sprintf("T:%S%s", host->name, pistring);
3559 /* If a delivery of another message over an existing SMTP connection
3560 yields DEFER, we do NOT set up retry data for the host. This covers the
3561 case when there are delays in routing the addresses in the second message
3562 that are so long that the server times out. This is alleviated by not
3563 routing addresses that previously had routing defers when handling an
3564 existing connection, but even so, this case may occur (e.g. if a
3565 previously happily routed address starts giving routing defers). If the
3566 host is genuinely down, another non-continued message delivery will
3567 notice it soon enough. */
3569 if (delete_flag != 0 || !continuing)
3570 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
3572 /* We may have tried an expired host, if its retry time has come; ensure
3573 the status reflects the expiry for the benefit of any other addresses. */
3577 host->status = (host_is_expired)?
3578 hstatus_unusable_expired : hstatus_unusable;
3579 host->why = hwhy_deferred;
3583 /* If message_defer is set (host was OK, but every recipient got deferred
3584 because of some message-specific problem), or if that had happened
3585 previously so that a message retry key exists, add an appropriate item
3586 to the retry chain. Note that if there was a message defer but now there is
3587 a host defer, the message defer record gets deleted. That seems perfectly
3588 reasonable. Also, stop the message from being remembered as waiting
3589 for specific hosts. */
3591 if (message_defer || retry_message_key != NULL)
3593 int delete_flag = message_defer? 0 : rf_delete;
3594 if (retry_message_key == NULL)
3597 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3598 US"retry_include_ip_address", ob->retry_include_ip_address,
3599 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3600 incl_ip = TRUE; /* error; use most-specific retry record */
3602 retry_message_key = incl_ip ?
3603 string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
3605 string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
3607 retry_add_item(addrlist, retry_message_key,
3608 rf_message | rf_host | delete_flag);
3609 update_waiting = FALSE;
3612 /* Any return other than DEFER (that is, OK or ERROR) means that the
3613 addresses have got their final statuses filled in for this host. In the OK
3614 case, see if any of them are deferred. */
3618 for (addr = addrlist; addr != NULL; addr = addr->next)
3620 if (addr->transport_return == DEFER)
3622 some_deferred = TRUE;
3628 /* If no addresses deferred or the result was ERROR, return. We do this for
3629 ERROR because a failing filter set-up or add_headers expansion is likely to
3630 fail for any host we try. */
3632 if (rc == ERROR || (rc == OK && !some_deferred))
3634 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3635 return TRUE; /* Each address has its status */
3638 /* If the result was DEFER or some individual addresses deferred, let
3639 the loop run to try other hosts with the deferred addresses, except for the
3640 case when we were trying to deliver down an existing channel and failed.
3641 Don't try any other hosts in this case. */
3643 if (continuing) break;
3645 /* If the whole delivery, or some individual addresses, were deferred and
3646 there are more hosts that could be tried, do not count this host towards
3647 the hosts_max_try limit if the age of the message is greater than the
3648 maximum retry time for this host. This means we may try try all hosts,
3649 ignoring the limit, when messages have been around for some time. This is
3650 important because if we don't try all hosts, the address will never time
3651 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
3653 if ((rc == DEFER || some_deferred) && nexthost != NULL)
3656 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
3658 if (retry != NULL && retry->rules != NULL)
3660 retry_rule *last_rule;
3661 for (last_rule = retry->rules;
3662 last_rule->next != NULL;
3663 last_rule = last_rule->next);
3664 timedout = time(NULL) - received_time > last_rule->timeout;
3666 else timedout = TRUE; /* No rule => timed out */
3670 unexpired_hosts_tried--;
3671 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
3672 "hosts_max_try (message older than host's retry time)\n");
3675 } /* End of loop for trying multiple hosts. */
3677 /* This is the end of the loop that repeats iff expired is TRUE and
3678 ob->delay_after_cutoff is FALSE. The second time round we will
3679 try those hosts that haven't been tried since the message arrived. */
3683 debug_printf("all IP addresses skipped or deferred at least one address\n");
3684 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
3685 debug_printf("retrying IP addresses not tried since message arrived\n");
3690 /* Get here if all IP addresses are skipped or defer at least one address. In
3691 MUA wrapper mode, this will happen only for connection or other non-message-
3692 specific failures. Force the delivery status for all addresses to FAIL. */
3696 for (addr = addrlist; addr != NULL; addr = addr->next)
3697 addr->transport_return = FAIL;
3701 /* In the normal, non-wrapper case, add a standard message to each deferred
3702 address if there hasn't been an error, that is, if it hasn't actually been
3703 tried this time. The variable "expired" will be FALSE if any deliveries were
3704 actually tried, or if there was at least one host that was not expired. That
3705 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
3706 a delivery has been tried, an error code will be set, and the failing of the
3707 message is handled by the retry code later.
3709 If queue_smtp is set, or this transport was called to send a subsequent message
3710 down an existing TCP/IP connection, and something caused the host not to be
3711 found, we end up here, but can detect these cases and handle them specially. */
3713 for (addr = addrlist; addr != NULL; addr = addr->next)
3715 /* If host is not NULL, it means that we stopped processing the host list
3716 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
3717 means we need to behave as if some hosts were skipped because their retry
3718 time had not come. Specifically, this prevents the address from timing out.
3719 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
3720 hosts were tried. */
3724 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
3727 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
3728 "hosts were tried\n");
3733 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
3734 setflag(addr, af_retry_skipped);
3738 if (queue_smtp) /* no deliveries attempted */
3740 addr->transport_return = DEFER;
3741 addr->basic_errno = 0;
3742 addr->message = US"SMTP delivery explicitly queued";
3745 else if (addr->transport_return == DEFER &&
3746 (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0) &&
3747 addr->message == NULL)
3749 addr->basic_errno = ERRNO_HRETRY;
3750 if (continue_hostname != NULL)
3752 addr->message = US"no host found for existing SMTP connection";
3756 setflag(addr, af_pass_message); /* This is not a security risk */
3757 addr->message = (ob->delay_after_cutoff)?
3758 US"retry time not reached for any host after a long failure period" :
3759 US"all hosts have been failing for a long time and were last tried "
3760 "after this message arrived";
3762 /* If we are already using fallback hosts, or there are no fallback hosts
3763 defined, convert the result to FAIL to cause a bounce. */
3765 if (addr->host_list == addr->fallback_hosts ||
3766 addr->fallback_hosts == NULL)
3767 addr->transport_return = FAIL;
3771 if (hosts_retry == hosts_total)
3772 addr->message = US"retry time not reached for any host";
3773 else if (hosts_fail == hosts_total)
3774 addr->message = US"all host address lookups failed permanently";
3775 else if (hosts_defer == hosts_total)
3776 addr->message = US"all host address lookups failed temporarily";
3777 else if (hosts_serial == hosts_total)
3778 addr->message = US"connection limit reached for all hosts";
3779 else if (hosts_fail+hosts_defer == hosts_total)
3780 addr->message = US"all host address lookups failed";
3781 else addr->message = US"some host address lookups failed and retry time "
3782 "not reached for other hosts or connection limit reached";
3787 /* Update the database which keeps information about which messages are waiting
3788 for which hosts to become available. For some message-specific errors, the
3789 update_waiting flag is turned off because we don't want follow-on deliveries in
3790 those cases. If this transport instance is explicitly limited to one message
3791 per connection then follow-on deliveries are not possible and there's no need
3792 to create/update the per-transport wait-<transport_name> database. */
3794 if (update_waiting && tblock->connection_max_messages != 1)
3795 transport_update_waiting(hostlist, tblock->name);
3799 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3801 return TRUE; /* Each address has its status */
3806 /* End of transport/smtp.c */
git://git.exim.org / exim.git / blob