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 US"*", /* 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
255 ,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 BOOL dsn_all_lasthop = TRUE;
1359 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1362 dns_answer tlsa_dnsa;
1364 smtp_inblock inblock;
1365 smtp_outblock outblock;
1366 int max_rcpt = tblock->max_addresses;
1367 uschar *igquotstr = US"";
1369 uschar *helo_data = NULL;
1371 uschar *message = NULL;
1372 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
1374 uschar buffer[4096];
1375 uschar inbuffer[4096];
1376 uschar outbuffer[4096];
1377 address_item * current_address;
1379 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
1381 *message_defer = FALSE;
1382 smtp_command = US"initial connection";
1383 if (max_rcpt == 0) max_rcpt = 999999;
1385 /* Set up the buffer for reading SMTP response packets. */
1387 inblock.buffer = inbuffer;
1388 inblock.buffersize = sizeof(inbuffer);
1389 inblock.ptr = inbuffer;
1390 inblock.ptrend = inbuffer;
1392 /* Set up the buffer for holding SMTP commands while pipelining */
1394 outblock.buffer = outbuffer;
1395 outblock.buffersize = sizeof(outbuffer);
1396 outblock.ptr = outbuffer;
1397 outblock.cmd_count = 0;
1398 outblock.authenticating = FALSE;
1400 /* Reset the parameters of a TLS session. */
1403 tls_out.cipher = NULL; /* the one we may use for this transport */
1404 tls_out.ourcert = NULL;
1405 tls_out.peercert = NULL;
1406 tls_out.peerdn = NULL;
1407 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1410 tls_out.ocsp = OCSP_NOT_REQ;
1412 /* Flip the legacy TLS-related variables over to the outbound set in case
1413 they're used in the context of the transport. Don't bother resetting
1414 afterward as we're in a subprocess. */
1416 tls_modify_variables(&tls_out);
1421 set_errno(addrlist, ERRNO_TLSFAILURE, US"TLS support not available",
1422 DEFER, FALSE, NULL);
1427 /* Make a connection to the host if this isn't a continued delivery, and handle
1428 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
1429 specially so they can be identified for retries. */
1431 if (continue_hostname == NULL)
1433 /* This puts port into host->port */
1434 inblock.sock = outblock.sock =
1435 smtp_connect(host, host_af, port, interface, ob->connect_timeout, tblock);
1437 if (inblock.sock < 0)
1439 set_errno(addrlist, (errno == ETIMEDOUT)? ERRNO_CONNECTTIMEOUT : errno,
1440 NULL, DEFER, FALSE, NULL);
1444 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1446 tls_out.dane_verified = FALSE;
1447 tls_out.tlsa_usage = 0;
1449 dane_required = verify_check_given_host(&ob->hosts_require_dane, host) == OK;
1451 if (host->dnssec == DS_YES)
1454 || verify_check_given_host(&ob->hosts_try_dane, host) == OK
1456 if ((rc = tlsa_lookup(host, &tlsa_dnsa, dane_required, &dane)) != OK)
1459 else if (dane_required)
1461 log_write(0, LOG_MAIN, "DANE error: %s lookup not DNSSEC", host->name);
1466 ob->tls_tempfail_tryclear = FALSE;
1470 /* Expand the greeting message while waiting for the initial response. (Makes
1471 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1472 delayed till here so that $sending_interface and $sending_port are set. */
1474 helo_data = expand_string(ob->helo_data);
1476 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1477 is nevertheless a reasonably clean way of programming this kind of logic,
1478 where you want to escape on any error. */
1482 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1483 ob->command_timeout)) goto RESPONSE_FAILED;
1485 #ifdef EXPERIMENTAL_EVENT
1488 lookup_dnssec_authenticated = host->dnssec==DS_YES ? US"yes"
1489 : host->dnssec==DS_NO ? US"no" : NULL;
1490 s = event_raise(tblock->event_action, US"smtp:connect", buffer);
1493 set_errno(addrlist, ERRNO_EXPANDFAIL,
1494 string_sprintf("deferred by smtp:connect event expansion: %s", s),
1495 DEFER, FALSE, NULL);
1502 /* Now check if the helo_data expansion went well, and sign off cleanly if
1505 if (helo_data == NULL)
1507 uschar *message = string_sprintf("failed to expand helo_data: %s",
1508 expand_string_message);
1509 set_errno(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, NULL);
1515 /** Debugging without sending a message
1516 addrlist->transport_return = DEFER;
1520 /* Errors that occur after this point follow an SMTP command, which is
1521 left in big_buffer by smtp_write_command() for use in error messages. */
1523 smtp_command = big_buffer;
1525 /* Tell the remote who we are...
1527 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1528 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1529 greeting is of this form. The assumption was that the far end supports it
1530 properly... but experience shows that there are some that give 5xx responses,
1531 even though the banner includes "ESMTP" (there's a bloody-minded one that
1532 says "ESMTP not spoken here"). Cope with that case.
1534 September 2000: Time has passed, and it seems reasonable now to always send
1535 EHLO at the start. It is also convenient to make the change while installing
1538 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1539 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1540 would be no way to send out the mails, so there is now a host list
1541 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1542 PIPELINING problem as well. Maybe it can also be useful to cure other
1543 problems with broken servers.
1545 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1546 Then somebody tried it with a Microsoft mailer... It seems that all other
1547 mailers use upper case for some reason (the RFC is quite clear about case
1548 independence) so, for peace of mind, I gave in. */
1550 esmtp = verify_check_given_host(&ob->hosts_avoid_esmtp, host) != OK;
1552 /* Alas; be careful, since this goto is not an error-out, so conceivably
1553 we might set data between here and the target which we assume to exist
1554 and be usable. I can see this coming back to bite us. */
1559 suppress_tls = FALSE;
1560 ob->tls_tempfail_tryclear = FALSE;
1561 smtp_command = US"SSL-on-connect";
1568 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1569 lmtp? "LHLO" : "EHLO", helo_data) < 0)
1571 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1572 ob->command_timeout))
1574 if (errno != 0 || buffer[0] == 0 || lmtp) goto RESPONSE_FAILED;
1581 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1586 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1588 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1589 ob->command_timeout)) goto RESPONSE_FAILED;
1592 /* Set IGNOREQUOTA if the response to LHLO specifies support and the
1593 lmtp_ignore_quota option was set. */
1595 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1596 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1597 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1599 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1602 tls_offered = esmtp &&
1603 pcre_exec(regex_STARTTLS, NULL, CS buffer, Ustrlen(buffer), 0,
1604 PCRE_EOPT, NULL, 0) >= 0;
1607 #ifndef DISABLE_PRDR
1608 prdr_offered = esmtp
1609 && pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(buffer), 0,
1610 PCRE_EOPT, NULL, 0) >= 0
1611 && verify_check_given_host(&ob->hosts_try_prdr, host) == OK;
1614 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1618 /* For continuing deliveries down the same channel, the socket is the standard
1619 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1620 below). Set up the pointer to where subsequent commands will be left, for
1621 error messages. Note that smtp_use_size and smtp_use_pipelining will have been
1622 set from the command line if they were set in the process that passed the
1627 inblock.sock = outblock.sock = fileno(stdin);
1628 smtp_command = big_buffer;
1629 host->port = port; /* Record the port that was used */
1632 /* If TLS is available on this connection, whether continued or not, attempt to
1633 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1634 send another EHLO - the server may give a different answer in secure mode. We
1635 use a separate buffer for reading the response to STARTTLS so that if it is
1636 negative, the original EHLO data is available for subsequent analysis, should
1637 the client not be required to use TLS. If the response is bad, copy the buffer
1638 for error analysis. */
1643 && verify_check_given_host(&ob->hosts_avoid_tls, host) != OK)
1645 uschar buffer2[4096];
1646 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1649 /* If there is an I/O error, transmission of this message is deferred. If
1650 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1651 false, we also defer. However, if there is a temporary rejection of STARTTLS
1652 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1653 STARTTLS, we carry on. This means we will try to send the message in clear,
1654 unless the host is in hosts_require_tls (tested below). */
1656 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1657 ob->command_timeout))
1659 if (errno != 0 || buffer2[0] == 0 ||
1660 (buffer2[0] == '4' && !ob->tls_tempfail_tryclear))
1662 Ustrncpy(buffer, buffer2, sizeof(buffer));
1663 goto RESPONSE_FAILED;
1667 /* STARTTLS accepted: try to negotiate a TLS session. */
1672 int rc = tls_client_start(inblock.sock, host, addrlist, tblock
1673 # ifdef EXPERIMENTAL_DANE
1674 , dane ? &tlsa_dnsa : NULL
1678 /* TLS negotiation failed; give an error. From outside, this function may
1679 be called again to try in clear on a new connection, if the options permit
1680 it for this host. */
1684 # ifdef EXPERIMENTAL_DANE
1685 if (rc == DEFER && dane && !dane_required)
1687 log_write(0, LOG_MAIN, "DANE attempt failed;"
1688 " trying CA-root TLS to %s [%s] (not in hosts_require_dane)",
1689 host->name, host->address);
1695 save_errno = ERRNO_TLSFAILURE;
1696 message = US"failure while setting up TLS session";
1701 /* TLS session is set up */
1703 for (addr = addrlist; addr != NULL; addr = addr->next)
1704 if (addr->transport_return == PENDING_DEFER)
1706 addr->cipher = tls_out.cipher;
1707 addr->ourcert = tls_out.ourcert;
1708 addr->peercert = tls_out.peercert;
1709 addr->peerdn = tls_out.peerdn;
1710 addr->ocsp = tls_out.ocsp;
1715 /* if smtps, we'll have smtp_command set to something else; always safe to
1717 smtp_command = big_buffer;
1719 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1720 helo_data is null, we are dealing with a connection that was passed from
1721 another process, and so we won't have expanded helo_data above. We have to
1722 expand it here. $sending_ip_address and $sending_port are set up right at the
1723 start of the Exim process (in exim.c). */
1725 if (tls_out.active >= 0)
1728 if (helo_data == NULL)
1730 helo_data = expand_string(ob->helo_data);
1731 if (helo_data == NULL)
1733 uschar *message = string_sprintf("failed to expand helo_data: %s",
1734 expand_string_message);
1735 set_errno(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, NULL);
1741 /* For SMTPS we need to wait for the initial OK response. */
1744 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1745 ob->command_timeout)) goto RESPONSE_FAILED;
1749 greeting_cmd = "EHLO";
1752 greeting_cmd = "HELO";
1754 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1757 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1758 lmtp? "LHLO" : greeting_cmd, helo_data) < 0)
1760 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1761 ob->command_timeout))
1762 goto RESPONSE_FAILED;
1765 /* If the host is required to use a secure channel, ensure that we
1769 # ifdef EXPERIMENTAL_DANE
1772 verify_check_given_host(&ob->hosts_require_tls, host) == OK
1775 save_errno = ERRNO_TLSREQUIRED;
1776 message = string_sprintf("a TLS session is required, but %s",
1777 tls_offered? "an attempt to start TLS failed" :
1778 "the server did not offer TLS support");
1781 #endif /*SUPPORT_TLS*/
1783 /* If TLS is active, we have just started it up and re-done the EHLO command,
1784 so its response needs to be analyzed. If TLS is not active and this is a
1785 continued session down a previously-used socket, we haven't just done EHLO, so
1788 if (continue_hostname == NULL
1790 || tls_out.active >= 0
1794 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
1795 lmtp_ignore_quota option was set. */
1797 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1798 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1799 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1801 /* If the response to EHLO specified support for the SIZE parameter, note
1802 this, provided size_addition is non-negative. */
1804 smtp_use_size = esmtp && ob->size_addition >= 0 &&
1805 pcre_exec(regex_SIZE, NULL, CS buffer, Ustrlen(CS buffer), 0,
1806 PCRE_EOPT, NULL, 0) >= 0;
1808 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
1809 the current host, esmtp will be false, so PIPELINING can never be used. If
1810 the current host matches hosts_avoid_pipelining, don't do it. */
1812 smtp_use_pipelining = esmtp
1813 && verify_check_given_host(&ob->hosts_avoid_pipelining, host) != OK
1814 && pcre_exec(regex_PIPELINING, NULL, CS buffer, Ustrlen(CS buffer), 0,
1815 PCRE_EOPT, NULL, 0) >= 0;
1817 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
1818 smtp_use_pipelining? "" : "not ");
1820 #ifndef DISABLE_PRDR
1821 prdr_offered = esmtp
1822 && pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(CS buffer), 0,
1823 PCRE_EOPT, NULL, 0) >= 0
1824 && verify_check_given_host(&ob->hosts_try_prdr, host) == OK;
1827 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1830 /* Note if the server supports DSN */
1831 smtp_use_dsn = esmtp && pcre_exec(regex_DSN, NULL, CS buffer, (int)Ustrlen(CS buffer), 0,
1832 PCRE_EOPT, NULL, 0) >= 0;
1833 DEBUG(D_transport) debug_printf("use_dsn=%d\n", smtp_use_dsn);
1835 /* Note if the response to EHLO specifies support for the AUTH extension.
1836 If it has, check that this host is one we want to authenticate to, and do
1837 the business. The host name and address must be available when the
1838 authenticator's client driver is running. */
1840 switch (yield = smtp_auth(buffer, sizeof(buffer), addrlist, host,
1841 ob, esmtp, &inblock, &outblock))
1843 default: goto SEND_QUIT;
1845 case FAIL_SEND: goto SEND_FAILED;
1846 case FAIL: goto RESPONSE_FAILED;
1850 /* The setting up of the SMTP call is now complete. Any subsequent errors are
1851 message-specific. */
1855 /* If there is a filter command specified for this transport, we can now
1856 set it up. This cannot be done until the identify of the host is known. */
1858 if (tblock->filter_command != NULL)
1862 sprintf(CS buffer, "%.50s transport", tblock->name);
1863 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
1864 TRUE, DEFER, addrlist, buffer, NULL);
1865 transport_filter_timeout = tblock->filter_timeout;
1867 /* On failure, copy the error to all addresses, abandon the SMTP call, and
1872 set_errno(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
1880 /* For messages that have more than the maximum number of envelope recipients,
1881 we want to send several transactions down the same SMTP connection. (See
1882 comments in deliver.c as to how this reconciles, heuristically, with
1883 remote_max_parallel.) This optimization was added to Exim after the following
1884 code was already working. The simplest way to put it in without disturbing the
1885 code was to use a goto to jump back to this point when there is another
1886 transaction to handle. */
1889 sync_addr = first_addr;
1893 completed_address = FALSE;
1896 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
1897 qualification, send it, adding something to the message size to allow for
1898 imprecision and things that get added en route. Exim keeps the number of lines
1899 in a message, so we can give an accurate value for the original message, but we
1900 need some additional to handle added headers. (Double "." characters don't get
1901 included in the count.) */
1908 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
1912 #ifndef DISABLE_PRDR
1913 prdr_active = FALSE;
1916 for (addr = first_addr; addr; addr = addr->next)
1917 if (addr->transport_return == PENDING_DEFER)
1919 for (addr = addr->next; addr; addr = addr->next)
1920 if (addr->transport_return == PENDING_DEFER)
1921 { /* at least two recipients to send */
1923 sprintf(CS p, " PRDR"); p += 5;
1931 /* check if all addresses have lasthop flag */
1932 /* do not send RET and ENVID if true */
1933 dsn_all_lasthop = TRUE;
1934 for (addr = first_addr;
1935 address_count < max_rcpt && addr != NULL;
1937 if ((addr->dsn_flags & rf_dsnlasthop) != 1)
1938 dsn_all_lasthop = FALSE;
1940 /* Add any DSN flags to the mail command */
1942 if ((smtp_use_dsn) && (dsn_all_lasthop == FALSE))
1944 if (dsn_ret == dsn_ret_hdrs)
1946 Ustrcpy(p, " RET=HDRS");
1949 else if (dsn_ret == dsn_ret_full)
1951 Ustrcpy(p, " RET=FULL");
1954 if (dsn_envid != NULL)
1956 string_format(p, sizeof(buffer) - (p-buffer), " ENVID=%s", dsn_envid);
1961 /* If an authenticated_sender override has been specified for this transport
1962 instance, expand it. If the expansion is forced to fail, and there was already
1963 an authenticated_sender for this message, the original value will be used.
1964 Other expansion failures are serious. An empty result is ignored, but there is
1965 otherwise no check - this feature is expected to be used with LMTP and other
1966 cases where non-standard addresses (e.g. without domains) might be required. */
1968 if (smtp_mail_auth_str(p, sizeof(buffer) - (p-buffer), addrlist, ob))
1974 /* From here until we send the DATA command, we can make use of PIPELINING
1975 if the server host supports it. The code has to be able to check the responses
1976 at any point, for when the buffer fills up, so we write it totally generally.
1977 When PIPELINING is off, each command written reports that it has flushed the
1980 pending_MAIL = TRUE; /* The block starts with MAIL */
1982 rc = smtp_write_command(&outblock, smtp_use_pipelining,
1983 "MAIL FROM:<%s>%s\r\n", return_path, buffer);
1984 mail_command = string_copy(big_buffer); /* Save for later error message */
1988 case -1: /* Transmission error */
1991 case +1: /* Block was sent */
1992 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1993 ob->command_timeout))
1995 if (errno == 0 && buffer[0] == '4')
1997 errno = ERRNO_MAIL4XX;
1998 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2000 goto RESPONSE_FAILED;
2002 pending_MAIL = FALSE;
2006 /* Pass over all the relevant recipient addresses for this host, which are the
2007 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
2008 several before we have to read the responses for those seen so far. This
2009 checking is done by a subroutine because it also needs to be done at the end.
2010 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
2011 the next one if not all are sent.
2013 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
2014 last address because we want to abort if any recipients have any kind of
2015 problem, temporary or permanent. We know that all recipient addresses will have
2016 the PENDING_DEFER status, because only one attempt is ever made, and we know
2017 that max_rcpt will be large, so all addresses will be done at once. */
2019 for (addr = first_addr;
2020 address_count < max_rcpt && addr != NULL;
2026 addr->dsn_aware = smtp_use_dsn ? dsn_support_yes : dsn_support_no;
2028 if (addr->transport_return != PENDING_DEFER) continue;
2031 no_flush = smtp_use_pipelining && (!mua_wrapper || addr->next != NULL);
2033 /* Add any DSN flags to the rcpt command and add to the sent string */
2038 if (smtp_use_dsn && (addr->dsn_flags & rf_dsnlasthop) != 1)
2040 if ((addr->dsn_flags & rf_dsnflags) != 0)
2044 Ustrcpy(p, " NOTIFY=");
2046 for (i = 0; i < 4; i++)
2047 if ((addr->dsn_flags & rf_list[i]) != 0)
2049 if (!first) *p++ = ',';
2051 Ustrcpy(p, rf_names[i]);
2056 if (addr->dsn_orcpt != NULL)
2058 string_format(p, sizeof(buffer) - (p-buffer), " ORCPT=%s",
2064 /* Now send the RCPT command, and process outstanding responses when
2065 necessary. After a timeout on RCPT, we just end the function, leaving the
2066 yield as OK, because this error can often mean that there is a problem with
2067 just one address, so we don't want to delay the host. */
2069 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s%s\r\n",
2070 transport_rcpt_address(addr, tblock->rcpt_include_affixes), igquotstr, buffer);
2072 if (count < 0) goto SEND_FAILED;
2075 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
2076 &sync_addr, host, count, ob->address_retry_include_sender,
2077 pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
2080 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2081 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2084 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2085 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2086 case 0: /* No 2xx or 5xx, but no probs */
2089 case -1: goto END_OFF; /* Timeout on RCPT */
2090 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
2092 pending_MAIL = FALSE; /* Dealt with MAIL */
2094 } /* Loop for next address */
2096 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
2097 permanently or temporarily. We should have flushed and synced after the last
2102 address_item *badaddr;
2103 for (badaddr = first_addr; badaddr; badaddr = badaddr->next)
2104 if (badaddr->transport_return != PENDING_OK)
2106 /*XXX could we find a better errno than 0 here? */
2107 set_errno(addrlist, 0, badaddr->message, FAIL,
2108 testflag(badaddr, af_pass_message), NULL);
2114 /* If ok is TRUE, we know we have got at least one good recipient, and must now
2115 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
2116 have a good recipient buffered up if we are pipelining. We don't want to waste
2117 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
2118 are pipelining. The responses are all handled by sync_responses(). */
2120 if (ok || (smtp_use_pipelining && !mua_wrapper))
2122 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
2123 if (count < 0) goto SEND_FAILED;
2124 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
2125 host, count, ob->address_retry_include_sender, pending_MAIL,
2126 ok? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
2128 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2129 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2132 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2133 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2134 case 0: break; /* No 2xx or 5xx, but no probs */
2136 case -1: goto END_OFF; /* Timeout on RCPT */
2137 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2141 /* Save the first address of the next batch. */
2145 /* If there were no good recipients (but otherwise there have been no
2146 problems), just set ok TRUE, since we have handled address-specific errors
2147 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
2148 for handling the SMTP dot-handling protocol, flagging to apply to headers as
2149 well as body. Set the appropriate timeout value to be used for each chunk.
2150 (Haven't been able to make it work using select() for writing yet.) */
2152 if (!ok) ok = TRUE; else
2154 sigalrm_seen = FALSE;
2155 transport_write_timeout = ob->data_timeout;
2156 smtp_command = US"sending data block"; /* For error messages */
2157 DEBUG(D_transport|D_v)
2158 debug_printf(" SMTP>> writing message and terminating \".\"\n");
2159 transport_count = 0;
2161 #ifndef DISABLE_DKIM
2162 ok = dkim_transport_write_message(addrlist, inblock.sock,
2163 topt_use_crlf | topt_end_dot | topt_escape_headers |
2164 (tblock->body_only? topt_no_headers : 0) |
2165 (tblock->headers_only? topt_no_body : 0) |
2166 (tblock->return_path_add? topt_add_return_path : 0) |
2167 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
2168 (tblock->envelope_to_add? topt_add_envelope_to : 0),
2169 0, /* No size limit */
2170 tblock->add_headers, tblock->remove_headers,
2171 US".", US"..", /* Escaping strings */
2172 tblock->rewrite_rules, tblock->rewrite_existflags,
2173 ob->dkim_private_key, ob->dkim_domain, ob->dkim_selector,
2174 ob->dkim_canon, ob->dkim_strict, ob->dkim_sign_headers
2177 ok = transport_write_message(addrlist, inblock.sock,
2178 topt_use_crlf | topt_end_dot | topt_escape_headers |
2179 (tblock->body_only? topt_no_headers : 0) |
2180 (tblock->headers_only? topt_no_body : 0) |
2181 (tblock->return_path_add? topt_add_return_path : 0) |
2182 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
2183 (tblock->envelope_to_add? topt_add_envelope_to : 0),
2184 0, /* No size limit */
2185 tblock->add_headers, tblock->remove_headers,
2186 US".", US"..", /* Escaping strings */
2187 tblock->rewrite_rules, tblock->rewrite_existflags);
2190 /* transport_write_message() uses write() because it is called from other
2191 places to write to non-sockets. This means that under some OS (e.g. Solaris)
2192 it can exit with "Broken pipe" as its error. This really means that the
2193 socket got closed at the far end. */
2195 transport_write_timeout = 0; /* for subsequent transports */
2197 /* Failure can either be some kind of I/O disaster (including timeout),
2198 or the failure of a transport filter or the expansion of added headers. */
2202 buffer[0] = 0; /* There hasn't been a response */
2203 goto RESPONSE_FAILED;
2206 /* We used to send the terminating "." explicitly here, but because of
2207 buffering effects at both ends of TCP/IP connections, you don't gain
2208 anything by keeping it separate, so it might as well go in the final
2209 data buffer for efficiency. This is now done by setting the topt_end_dot
2212 smtp_command = US"end of data";
2214 #ifndef DISABLE_PRDR
2215 /* For PRDR we optionally get a partial-responses warning
2216 * followed by the individual responses, before going on with
2217 * the overall response. If we don't get the warning then deal
2218 * with per non-PRDR. */
2221 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '3',
2223 if (!ok && errno == 0)
2226 case '2': prdr_active = FALSE;
2229 case '4': errno = ERRNO_DATA4XX;
2230 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2237 /* For non-PRDR SMTP, we now read a single response that applies to the
2238 whole message. If it is OK, then all the addresses have been delivered. */
2242 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2244 if (!ok && errno == 0 && buffer[0] == '4')
2246 errno = ERRNO_DATA4XX;
2247 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2251 /* For LMTP, we get back a response for every RCPT command that we sent;
2252 some may be accepted and some rejected. For those that get a response, their
2253 status is fixed; any that are accepted have been handed over, even if later
2254 responses crash - at least, that's how I read RFC 2033.
2256 If all went well, mark the recipient addresses as completed, record which
2257 host/IPaddress they were delivered to, and cut out RSET when sending another
2258 message down the same channel. Write the completed addresses to the journal
2259 now so that they are recorded in case there is a crash of hardware or
2260 software before the spool gets updated. Also record the final SMTP
2261 confirmation if needed (for SMTP only). */
2266 int delivery_time = (int)(time(NULL) - start_delivery_time);
2268 uschar *conf = NULL;
2271 /* Set up confirmation if needed - applies only to SMTP */
2274 #ifndef EXPERIMENTAL_EVENT
2275 (log_extra_selector & LX_smtp_confirmation) != 0 &&
2280 const uschar *s = string_printing(buffer);
2281 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
2282 conf = (s == buffer)? (uschar *)string_copy(s) : US s;
2285 /* Process all transported addresses - for LMTP or PRDR, read a status for
2288 for (addr = addrlist; addr != first_addr; addr = addr->next)
2290 if (addr->transport_return != PENDING_OK) continue;
2292 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
2293 remaining addresses. Otherwise, it's a return code for just the one
2294 address. For temporary errors, add a retry item for the address so that
2295 it doesn't get tried again too soon. */
2297 #ifndef DISABLE_PRDR
2298 if (lmtp || prdr_active)
2303 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2306 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
2307 addr->message = string_sprintf(
2308 #ifndef DISABLE_PRDR
2309 "%s error after %s: %s", prdr_active ? "PRDR":"LMTP",
2311 "LMTP error after %s: %s",
2313 big_buffer, string_printing(buffer));
2314 setflag(addr, af_pass_message); /* Allow message to go to user */
2315 if (buffer[0] == '5')
2316 addr->transport_return = FAIL;
2319 errno = ERRNO_DATA4XX;
2320 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2321 addr->transport_return = DEFER;
2322 #ifndef DISABLE_PRDR
2325 retry_add_item(addr, addr->address_retry_key, 0);
2329 completed_address = TRUE; /* NOW we can set this flag */
2330 if ((log_extra_selector & LX_smtp_confirmation) != 0)
2332 const uschar *s = string_printing(buffer);
2333 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
2334 conf = (s == buffer)? (uschar *)string_copy(s) : US s;
2338 /* SMTP, or success return from LMTP for this address. Pass back the
2339 actual host that was used. */
2341 addr->transport_return = OK;
2342 addr->more_errno = delivery_time;
2343 addr->host_used = host;
2344 addr->special_action = flag;
2345 addr->message = conf;
2346 #ifndef DISABLE_PRDR
2347 if (prdr_active) addr->flags |= af_prdr_used;
2351 #ifndef DISABLE_PRDR
2355 /* Update the journal. For homonymic addresses, use the base address plus
2356 the transport name. See lots of comments in deliver.c about the reasons
2357 for the complications when homonyms are involved. Just carry on after
2358 write error, as it may prove possible to update the spool file later. */
2360 if (testflag(addr, af_homonym))
2361 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2363 sprintf(CS buffer, "%.500s\n", addr->unique);
2365 DEBUG(D_deliver) debug_printf("journalling %s", buffer);
2366 len = Ustrlen(CS buffer);
2367 if (write(journal_fd, buffer, len) != len)
2368 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2369 "%s: %s", buffer, strerror(errno));
2373 #ifndef DISABLE_PRDR
2376 /* PRDR - get the final, overall response. For any non-success
2377 upgrade all the address statuses. */
2378 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2382 if(errno == 0 && buffer[0] == '4')
2384 errno = ERRNO_DATA4XX;
2385 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2387 for (addr = addrlist; addr != first_addr; addr = addr->next)
2388 if (buffer[0] == '5' || addr->transport_return == OK)
2389 addr->transport_return = PENDING_OK; /* allow set_errno action */
2390 goto RESPONSE_FAILED;
2393 /* Update the journal, or setup retry. */
2394 for (addr = addrlist; addr != first_addr; addr = addr->next)
2395 if (addr->transport_return == OK)
2397 if (testflag(addr, af_homonym))
2398 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2400 sprintf(CS buffer, "%.500s\n", addr->unique);
2402 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s", buffer);
2403 len = Ustrlen(CS buffer);
2404 if (write(journal_fd, buffer, len) != len)
2405 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2406 "%s: %s", buffer, strerror(errno));
2408 else if (addr->transport_return == DEFER)
2409 retry_add_item(addr, addr->address_retry_key, -2);
2413 /* Ensure the journal file is pushed out to disk. */
2415 if (EXIMfsync(journal_fd) < 0)
2416 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
2422 /* Handle general (not specific to one address) failures here. The value of ok
2423 is used to skip over this code on the falling through case. A timeout causes a
2424 deferral. Other errors may defer or fail according to the response code, and
2425 may set up a special errno value, e.g. after connection chopped, which is
2426 assumed if errno == 0 and there is no text in the buffer. If control reaches
2427 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
2428 the problem is not related to this specific message. */
2437 send_quit = check_response(host, &save_errno, addrlist->more_errno,
2438 buffer, &code, &message, &pass_message);
2444 message = US string_sprintf("send() to %s [%s] failed: %s",
2445 host->name, host->address, strerror(save_errno));
2449 /* This label is jumped to directly when a TLS negotiation has failed,
2450 or was not done for a host for which it is required. Values will be set
2451 in message and save_errno, and setting_up will always be true. Treat as
2452 a temporary error. */
2459 /* If the failure happened while setting up the call, see if the failure was
2460 a 5xx response (this will either be on connection, or following HELO - a 5xx
2461 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
2462 never going to accept them. For other errors during setting up (timeouts or
2463 whatever), defer all addresses, and yield DEFER, so that the host is not
2464 tried again for a while. */
2467 ok = FALSE; /* For when reached by GOTO */
2472 set_errno(addrlist, save_errno, message, FAIL, pass_message, host);
2475 set_errno(addrlist, save_errno, message, DEFER, pass_message, host);
2480 /* We want to handle timeouts after MAIL or "." and loss of connection after
2481 "." specially. They can indicate a problem with the sender address or with
2482 the contents of the message rather than a real error on the connection. These
2483 cases are treated in the same way as a 4xx response. This next bit of code
2484 does the classification. */
2495 message_error = TRUE;
2499 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
2500 Ustrncmp(smtp_command,"end ",4) == 0;
2503 case ERRNO_SMTPCLOSED:
2504 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
2508 message_error = FALSE;
2512 /* Handle the cases that are treated as message errors. These are:
2514 (a) negative response or timeout after MAIL
2515 (b) negative response after DATA
2516 (c) negative response or timeout or dropped connection after "."
2518 It won't be a negative response or timeout after RCPT, as that is dealt
2519 with separately above. The action in all cases is to set an appropriate
2520 error code for all the addresses, but to leave yield set to OK because the
2521 host itself has not failed. Of course, it might in practice have failed
2522 when we've had a timeout, but if so, we'll discover that at the next
2523 delivery attempt. For a temporary error, set the message_defer flag, and
2524 write to the logs for information if this is not the last host. The error
2525 for the last host will be logged as part of the address's log line. */
2529 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
2530 set_errno(addrlist, save_errno, message, (code == '5')? FAIL : DEFER,
2531 pass_message, host);
2533 /* If there's an errno, the message contains just the identity of
2536 if (code != '5') /* Anything other than 5 is treated as temporary */
2539 message = US string_sprintf("%s: %s", message, strerror(save_errno));
2540 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
2541 msglog_line(host, message);
2542 *message_defer = TRUE;
2546 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
2547 ".", or some other transportation error. We defer all addresses and yield
2548 DEFER, except for the case of failed add_headers expansion, or a transport
2549 filter failure, when the yield should be ERROR, to stop it trying other
2554 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
2555 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
2556 set_errno(addrlist, save_errno, message, DEFER, pass_message, host);
2562 /* If all has gone well, send_quit will be set TRUE, implying we can end the
2563 SMTP session tidily. However, if there were too many addresses to send in one
2564 message (indicated by first_addr being non-NULL) we want to carry on with the
2565 rest of them. Also, it is desirable to send more than one message down the SMTP
2566 connection if there are several waiting, provided we haven't already sent so
2567 many as to hit the configured limit. The function transport_check_waiting looks
2568 for a waiting message and returns its id. Then transport_pass_socket tries to
2569 set up a continued delivery by passing the socket on to another process. The
2570 variable send_rset is FALSE if a message has just been successfully transfered.
2572 If we are already sending down a continued channel, there may be further
2573 addresses not yet delivered that are aimed at the same host, but which have not
2574 been passed in this run of the transport. In this case, continue_more will be
2575 true, and all we should do is send RSET if necessary, and return, leaving the
2578 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
2579 do not want to continue with other messages down the same channel, because that
2580 can lead to looping between two or more messages, all with the same,
2581 temporarily failing address(es). [The retry information isn't updated yet, so
2582 new processes keep on trying.] We probably also don't want to try more of this
2583 message's addresses either.
2585 If we have started a TLS session, we have to end it before passing the
2586 connection to a new process. However, not all servers can handle this (Exim
2587 can), so we do not pass such a connection on if the host matches
2588 hosts_nopass_tls. */
2591 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
2592 "yield=%d first_address is %sNULL\n", ok, send_quit, send_rset,
2593 continue_more, yield, (first_addr == NULL)? "":"not ");
2595 if (completed_address && ok && send_quit)
2598 smtp_compare_t t_compare;
2600 t_compare.tblock = tblock;
2601 t_compare.current_sender_address = sender_address;
2603 if ( first_addr != NULL
2605 || ( ( tls_out.active < 0
2606 || verify_check_given_host(&ob->hosts_nopass_tls, host) != OK
2609 transport_check_waiting(tblock->name, host->name,
2610 tblock->connection_max_messages, new_message_id, &more,
2611 (oicf)smtp_are_same_identities, (void*)&t_compare)
2619 if (! (ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
2621 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
2622 host->address, strerror(save_errno));
2625 else if (! (ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2626 ob->command_timeout)))
2629 send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
2633 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
2634 host->name, host->address, msg);
2639 /* Either RSET was not needed, or it succeeded */
2643 if (first_addr != NULL) /* More addresses still to be sent */
2644 { /* in this run of the transport */
2645 continue_sequence++; /* Causes * in logging */
2648 if (continue_more) return yield; /* More addresses for another run */
2650 /* Pass the socket to a new Exim process. Before doing so, we must shut
2651 down TLS. Not all MTAs allow for the continuation of the SMTP session
2652 when TLS is shut down. We test for this by sending a new EHLO. If we
2653 don't get a good response, we don't attempt to pass the socket on. */
2656 if (tls_out.active >= 0)
2658 tls_close(FALSE, TRUE);
2662 ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
2663 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2664 ob->command_timeout);
2668 /* If the socket is successfully passed, we musn't send QUIT (or
2669 indeed anything!) from here. */
2671 if (ok && transport_pass_socket(tblock->name, host->name, host->address,
2672 new_message_id, inblock.sock))
2678 /* If RSET failed and there are addresses left, they get deferred. */
2680 else set_errno(first_addr, errno, msg, DEFER, FALSE, host);
2684 /* End off tidily with QUIT unless the connection has died or the socket has
2685 been passed to another process. There has been discussion on the net about what
2686 to do after sending QUIT. The wording of the RFC suggests that it is necessary
2687 to wait for a response, but on the other hand, there isn't anything one can do
2688 with an error response, other than log it. Exim used to do that. However,
2689 further discussion suggested that it is positively advantageous not to wait for
2690 the response, but to close the session immediately. This is supposed to move
2691 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
2692 load from the server. (Hosts that are both servers and clients may not see much
2693 difference, of course.) Further discussion indicated that this was safe to do
2694 on Unix systems which have decent implementations of TCP/IP that leave the
2695 connection around for a while (TIME_WAIT) after the application has gone away.
2696 This enables the response sent by the server to be properly ACKed rather than
2697 timed out, as can happen on broken TCP/IP implementations on other OS.
2699 This change is being made on 31-Jul-98. After over a year of trouble-free
2700 operation, the old commented-out code was removed on 17-Sep-99. */
2703 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2708 tls_close(FALSE, TRUE);
2711 /* Close the socket, and return the appropriate value, first setting
2712 works because the NULL setting is passed back to the calling process, and
2713 remote_max_parallel is forced to 1 when delivering over an existing connection,
2715 If all went well and continue_more is set, we shouldn't actually get here if
2716 there are further addresses, as the return above will be taken. However,
2717 writing RSET might have failed, or there may be other addresses whose hosts are
2718 specified in the transports, and therefore not visible at top level, in which
2719 case continue_more won't get set. */
2721 (void)close(inblock.sock);
2723 #ifdef EXPERIMENTAL_EVENT
2724 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
2727 continue_transport = NULL;
2728 continue_hostname = NULL;
2735 /*************************************************
2736 * Closedown entry point *
2737 *************************************************/
2739 /* This function is called when exim is passed an open smtp channel
2740 from another incarnation, but the message which it has been asked
2741 to deliver no longer exists. The channel is on stdin.
2743 We might do fancy things like looking for another message to send down
2744 the channel, but if the one we sought has gone, it has probably been
2745 delivered by some other process that itself will seek further messages,
2746 so just close down our connection.
2748 Argument: pointer to the transport instance block
2753 smtp_transport_closedown(transport_instance *tblock)
2755 smtp_transport_options_block *ob =
2756 (smtp_transport_options_block *)(tblock->options_block);
2757 smtp_inblock inblock;
2758 smtp_outblock outblock;
2760 uschar inbuffer[4096];
2761 uschar outbuffer[16];
2763 inblock.sock = fileno(stdin);
2764 inblock.buffer = inbuffer;
2765 inblock.buffersize = sizeof(inbuffer);
2766 inblock.ptr = inbuffer;
2767 inblock.ptrend = inbuffer;
2769 outblock.sock = inblock.sock;
2770 outblock.buffersize = sizeof(outbuffer);
2771 outblock.buffer = outbuffer;
2772 outblock.ptr = outbuffer;
2773 outblock.cmd_count = 0;
2774 outblock.authenticating = FALSE;
2776 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2777 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2778 ob->command_timeout);
2779 (void)close(inblock.sock);
2784 /*************************************************
2785 * Prepare addresses for delivery *
2786 *************************************************/
2788 /* This function is called to flush out error settings from previous delivery
2789 attempts to other hosts. It also records whether we got here via an MX record
2790 or not in the more_errno field of the address. We are interested only in
2791 addresses that are still marked DEFER - others may have got delivered to a
2792 previously considered IP address. Set their status to PENDING_DEFER to indicate
2793 which ones are relevant this time.
2796 addrlist the list of addresses
2797 host the host we are delivering to
2799 Returns: the first address for this delivery
2802 static address_item *
2803 prepare_addresses(address_item *addrlist, host_item *host)
2805 address_item *first_addr = NULL;
2807 for (addr = addrlist; addr != NULL; addr = addr->next)
2808 if (addr->transport_return == DEFER)
2810 if (first_addr == NULL) first_addr = addr;
2811 addr->transport_return = PENDING_DEFER;
2812 addr->basic_errno = 0;
2813 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
2814 addr->message = NULL;
2816 addr->cipher = NULL;
2817 addr->ourcert = NULL;
2818 addr->peercert = NULL;
2819 addr->peerdn = NULL;
2820 addr->ocsp = OCSP_NOT_REQ;
2828 /*************************************************
2829 * Main entry point *
2830 *************************************************/
2832 /* See local README for interface details. As this is a remote transport, it is
2833 given a chain of addresses to be delivered in one connection, if possible. It
2834 always returns TRUE, indicating that each address has its own independent
2835 status set, except if there is a setting up problem, in which case it returns
2839 smtp_transport_entry(
2840 transport_instance *tblock, /* data for this instantiation */
2841 address_item *addrlist) /* addresses we are working on */
2845 int hosts_defer = 0;
2847 int hosts_looked_up = 0;
2848 int hosts_retry = 0;
2849 int hosts_serial = 0;
2850 int hosts_total = 0;
2851 int total_hosts_tried = 0;
2853 BOOL expired = TRUE;
2854 BOOL continuing = continue_hostname != NULL;
2855 uschar *expanded_hosts = NULL;
2857 uschar *tid = string_sprintf("%s transport", tblock->name);
2858 smtp_transport_options_block *ob =
2859 (smtp_transport_options_block *)(tblock->options_block);
2860 host_item *hostlist = addrlist->host_list;
2861 host_item *host = NULL;
2865 debug_printf("%s transport entered\n", tblock->name);
2866 for (addr = addrlist; addr != NULL; addr = addr->next)
2867 debug_printf(" %s\n", addr->address);
2868 if (continuing) debug_printf("already connected to %s [%s]\n",
2869 continue_hostname, continue_host_address);
2872 /* Set the flag requesting that these hosts be added to the waiting
2873 database if the delivery fails temporarily or if we are running with
2874 queue_smtp or a 2-stage queue run. This gets unset for certain
2875 kinds of error, typically those that are specific to the message. */
2877 update_waiting = TRUE;
2879 /* If a host list is not defined for the addresses - they must all have the
2880 same one in order to be passed to a single transport - or if the transport has
2881 a host list with hosts_override set, use the host list supplied with the
2882 transport. It is an error for this not to exist. */
2884 if (hostlist == NULL || (ob->hosts_override && ob->hosts != NULL))
2886 if (ob->hosts == NULL)
2888 addrlist->message = string_sprintf("%s transport called with no hosts set",
2890 addrlist->transport_return = PANIC;
2891 return FALSE; /* Only top address has status */
2894 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
2897 /* If the transport's host list contains no '$' characters, and we are not
2898 randomizing, it is fixed and therefore a chain of hosts can be built once
2899 and for all, and remembered for subsequent use by other calls to this
2900 transport. If, on the other hand, the host list does contain '$', or we are
2901 randomizing its order, we have to rebuild it each time. In the fixed case,
2902 as the hosts string will never be used again, it doesn't matter that we
2903 replace all the : characters with zeros. */
2905 if (ob->hostlist == NULL)
2907 uschar *s = ob->hosts;
2909 if (Ustrchr(s, '$') != NULL)
2911 if (!(expanded_hosts = expand_string(s)))
2913 addrlist->message = string_sprintf("failed to expand list of hosts "
2914 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
2915 addrlist->transport_return = search_find_defer? DEFER : PANIC;
2916 return FALSE; /* Only top address has status */
2918 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
2919 "\"%s\"\n", s, expanded_hosts);
2923 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
2925 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
2927 /* Check that the expansion yielded something useful. */
2928 if (hostlist == NULL)
2931 string_sprintf("%s transport has empty hosts setting", tblock->name);
2932 addrlist->transport_return = PANIC;
2933 return FALSE; /* Only top address has status */
2936 /* If there was no expansion of hosts, save the host list for
2939 if (!expanded_hosts) ob->hostlist = hostlist;
2942 /* This is not the first time this transport has been run in this delivery;
2943 the host list was built previously. */
2946 hostlist = ob->hostlist;
2949 /* The host list was supplied with the address. If hosts_randomize is set, we
2950 must sort it into a random order if it did not come from MX records and has not
2951 already been randomized (but don't bother if continuing down an existing
2954 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continuing)
2956 host_item *newlist = NULL;
2957 while (hostlist != NULL)
2959 host_item *h = hostlist;
2960 hostlist = hostlist->next;
2962 h->sort_key = random_number(100);
2964 if (newlist == NULL)
2969 else if (h->sort_key < newlist->sort_key)
2976 host_item *hh = newlist;
2977 while (hh->next != NULL)
2979 if (h->sort_key < hh->next->sort_key) break;
2987 hostlist = addrlist->host_list = newlist;
2990 /* Sort out the default port. */
2992 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
2994 /* For each host-plus-IP-address on the list:
2996 . If this is a continued delivery and the host isn't the one with the
2997 current connection, skip.
2999 . If the status is unusable (i.e. previously failed or retry checked), skip.
3001 . If no IP address set, get the address, either by turning the name into
3002 an address, calling gethostbyname if gethostbyname is on, or by calling
3003 the DNS. The DNS may yield multiple addresses, in which case insert the
3004 extra ones into the list.
3006 . Get the retry data if not previously obtained for this address and set the
3007 field which remembers the state of this address. Skip if the retry time is
3008 not reached. If not, remember whether retry data was found. The retry string
3009 contains both the name and the IP address.
3011 . Scan the list of addresses and mark those whose status is DEFER as
3012 PENDING_DEFER. These are the only ones that will be processed in this cycle
3015 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
3016 Some addresses may be successfully delivered, others may fail, and yet
3017 others may get temporary errors and so get marked DEFER.
3019 . The return from the delivery attempt is OK if a connection was made and a
3020 valid SMTP dialogue was completed. Otherwise it is DEFER.
3022 . If OK, add a "remove" retry item for this host/IPaddress, if any.
3024 . If fail to connect, or other defer state, add a retry item.
3026 . If there are any addresses whose status is still DEFER, carry on to the
3027 next host/IPaddress, unless we have tried the number of hosts given
3028 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
3029 there is some fancy logic for hosts_max_try that means its limit can be
3030 overstepped in some circumstances.
3032 If we get to the end of the list, all hosts have deferred at least one address,
3033 or not reached their retry times. If delay_after_cutoff is unset, it requests a
3034 delivery attempt to those hosts whose last try was before the arrival time of
3035 the current message. To cope with this, we have to go round the loop a second
3036 time. After that, set the status and error data for any addresses that haven't
3037 had it set already. */
3039 for (cutoff_retry = 0; expired &&
3040 cutoff_retry < ((ob->delay_after_cutoff)? 1 : 2);
3043 host_item *nexthost = NULL;
3044 int unexpired_hosts_tried = 0;
3046 for (host = hostlist;
3048 unexpired_hosts_tried < ob->hosts_max_try &&
3049 total_hosts_tried < ob->hosts_max_try_hardlimit;
3055 BOOL serialized = FALSE;
3056 BOOL host_is_expired = FALSE;
3057 BOOL message_defer = FALSE;
3058 BOOL ifchanges = FALSE;
3059 BOOL some_deferred = FALSE;
3060 address_item *first_addr = NULL;
3061 uschar *interface = NULL;
3062 uschar *retry_host_key = NULL;
3063 uschar *retry_message_key = NULL;
3064 uschar *serialize_key = NULL;
3066 /* Default next host is next host. :-) But this can vary if the
3067 hosts_max_try limit is hit (see below). It may also be reset if a host
3068 address is looked up here (in case the host was multihomed). */
3070 nexthost = host->next;
3072 /* If the address hasn't yet been obtained from the host name, look it up
3073 now, unless the host is already marked as unusable. If it is marked as
3074 unusable, it means that the router was unable to find its IP address (in
3075 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
3076 the lookup failed last time. We don't get this far if *all* MX records
3077 point to non-existent hosts; that is treated as a hard error.
3079 We can just skip this host entirely. When the hosts came from the router,
3080 the address will timeout based on the other host(s); when the address is
3081 looked up below, there is an explicit retry record added.
3083 Note that we mustn't skip unusable hosts if the address is not unset; they
3084 may be needed as expired hosts on the 2nd time round the cutoff loop. */
3086 if (host->address == NULL)
3088 int new_port, flags;
3091 if (host->status >= hstatus_unusable)
3093 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
3098 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
3100 /* The host name is permitted to have an attached port. Find it, and
3101 strip it from the name. Just remember it for now. */
3103 new_port = host_item_get_port(host);
3105 /* Count hosts looked up */
3109 /* Find by name if so configured, or if it's an IP address. We don't
3110 just copy the IP address, because we need the test-for-local to happen. */
3112 flags = HOST_FIND_BY_A;
3113 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
3114 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
3116 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
3117 rc = host_find_byname(host, NULL, flags, NULL, TRUE);
3119 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
3120 ob->dnssec_request_domains, ob->dnssec_require_domains,
3123 /* Update the host (and any additional blocks, resulting from
3124 multihoming) with a host-specific port, if any. */
3126 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
3128 /* Failure to find the host at this time (usually DNS temporary failure)
3129 is really a kind of routing failure rather than a transport failure.
3130 Therefore we add a retry item of the routing kind, not to stop us trying
3131 to look this name up here again, but to ensure the address gets timed
3132 out if the failures go on long enough. A complete failure at this point
3133 commonly points to a configuration error, but the best action is still
3134 to carry on for the next host. */
3136 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
3138 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
3140 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
3141 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
3142 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
3143 host->status = hstatus_unusable;
3145 for (addr = addrlist; addr != NULL; addr = addr->next)
3147 if (addr->transport_return != DEFER) continue;
3148 addr->basic_errno = ERRNO_UNKNOWNHOST;
3150 string_sprintf("failed to lookup IP address for %s", host->name);
3155 /* If the host is actually the local host, we may have a problem, or
3156 there may be some cunning configuration going on. In the problem case,
3157 log things and give up. The default transport status is already DEFER. */
3159 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
3161 for (addr = addrlist; addr != NULL; addr = addr->next)
3163 addr->basic_errno = 0;
3164 addr->message = string_sprintf("%s transport found host %s to be "
3165 "local", tblock->name, host->name);
3169 } /* End of block for IP address lookup */
3171 /* If this is a continued delivery, we are interested only in the host
3172 which matches the name of the existing open channel. The check is put
3173 here after the local host lookup, in case the name gets expanded as a
3174 result of the lookup. Set expired FALSE, to save the outer loop executing
3177 if (continuing && (Ustrcmp(continue_hostname, host->name) != 0 ||
3178 Ustrcmp(continue_host_address, host->address) != 0))
3181 continue; /* With next host */
3184 /* Reset the default next host in case a multihomed host whose addresses
3185 are not looked up till just above added to the host list. */
3187 nexthost = host->next;
3189 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
3190 domain is in queue_smtp_domains, we don't actually want to attempt any
3191 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
3192 there is a lookup defer in queue_smtp_domains, proceed as if the domain
3193 were not in it. We don't want to hold up all SMTP deliveries! Except when
3194 doing a two-stage queue run, don't do this if forcing. */
3196 if ((!deliver_force || queue_2stage) && (queue_smtp ||
3197 match_isinlist(addrlist->domain,
3198 (const uschar **)&queue_smtp_domains, 0,
3199 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
3202 for (addr = addrlist; addr != NULL; addr = addr->next)
3204 if (addr->transport_return != DEFER) continue;
3205 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
3207 continue; /* With next host */
3210 /* Count hosts being considered - purely for an intelligent comment
3211 if none are usable. */
3215 /* Set $host and $host address now in case they are needed for the
3216 interface expansion or the serialize_hosts check; they remain set if an
3217 actual delivery happens. */
3219 deliver_host = host->name;
3220 deliver_host_address = host->address;
3221 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
3222 : host->dnssec == DS_NO ? US"no"
3225 /* Set up a string for adding to the retry key if the port number is not
3226 the standard SMTP port. A host may have its own port setting that overrides
3229 pistring = string_sprintf(":%d", (host->port == PORT_NONE)?
3231 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
3233 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
3234 string changes upon expansion, we must add it to the key that is used for
3235 retries, because connections to the same host from a different interface
3236 should be treated separately. */
3238 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET : AF_INET6;
3239 if (!smtp_get_interface(ob->interface, host_af, addrlist, &ifchanges,
3242 if (ifchanges) pistring = string_sprintf("%s/%s", pistring, interface);
3244 /* The first time round the outer loop, check the status of the host by
3245 inspecting the retry data. The second time round, we are interested only
3246 in expired hosts that haven't been tried since this message arrived. */
3248 if (cutoff_retry == 0)
3251 /* Ensure the status of the address is set by checking retry data if
3252 necessary. There may be host-specific retry data (applicable to all
3253 messages) and also data for retries of a specific message at this host.
3254 If either of these retry records are actually read, the keys used are
3255 returned to save recomputing them later. */
3257 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3258 US"retry_include_ip_address", ob->retry_include_ip_address,
3259 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3260 continue; /* with next host */
3262 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
3263 incl_ip, &retry_host_key, &retry_message_key);
3265 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
3266 (host->address == NULL)? US"" : host->address, pistring,
3267 (host->status == hstatus_usable)? "usable" :
3268 (host->status == hstatus_unusable)? "unusable" :
3269 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
3271 /* Skip this address if not usable at this time, noting if it wasn't
3272 actually expired, both locally and in the address. */
3274 switch (host->status)
3276 case hstatus_unusable:
3278 setflag(addrlist, af_retry_skipped);
3281 case hstatus_unusable_expired:
3284 case hwhy_retry: hosts_retry++; break;
3285 case hwhy_failed: hosts_fail++; break;
3286 case hwhy_deferred: hosts_defer++; break;
3289 /* If there was a retry message key, implying that previously there
3290 was a message-specific defer, we don't want to update the list of
3291 messages waiting for these hosts. */
3293 if (retry_message_key != NULL) update_waiting = FALSE;
3294 continue; /* With the next host or IP address */
3298 /* Second time round the loop: if the address is set but expired, and
3299 the message is newer than the last try, let it through. */
3303 if (host->address == NULL ||
3304 host->status != hstatus_unusable_expired ||
3305 host->last_try > received_time)
3308 debug_printf("trying expired host %s [%s]%s\n",
3309 host->name, host->address, pistring);
3310 host_is_expired = TRUE;
3313 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
3314 it remains TRUE only if all hosts are expired and none are actually tried.
3319 /* If this host is listed as one to which access must be serialized,
3320 see if another Exim process has a connection to it, and if so, skip
3321 this host. If not, update the database to record our connection to it
3322 and remember this for later deletion. Do not do any of this if we are
3323 sending the message down a pre-existing connection. */
3326 verify_check_given_host(&ob->serialize_hosts, host) == OK)
3328 serialize_key = string_sprintf("host-serialize-%s", host->name);
3329 if (!enq_start(serialize_key))
3332 debug_printf("skipping host %s because another Exim process "
3333 "is connected to it\n", host->name);
3340 /* OK, we have an IP address that is not waiting for its retry time to
3341 arrive (it might be expired) OR (second time round the loop) we have an
3342 expired host that hasn't been tried since the message arrived. Have a go
3343 at delivering the message to it. First prepare the addresses by flushing
3344 out the result of previous attempts, and finding the first address that
3345 is still to be delivered. */
3347 first_addr = prepare_addresses(addrlist, host);
3349 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
3350 message_id, host->name, host->address, addrlist->address,
3351 (addrlist->next == NULL)? "" : ", ...");
3353 set_process_info("delivering %s to %s [%s] (%s%s)",
3354 message_id, host->name, host->address, addrlist->address,
3355 (addrlist->next == NULL)? "" : ", ...");
3357 /* This is not for real; don't do the delivery. If there are
3358 any remaining hosts, list them. */
3363 set_errno(addrlist, 0, NULL, OK, FALSE, NULL);
3364 for (addr = addrlist; addr != NULL; addr = addr->next)
3366 addr->host_used = host;
3367 addr->special_action = '*';
3368 addr->message = US"delivery bypassed by -N option";
3372 debug_printf("*** delivery by %s transport bypassed by -N option\n"
3373 "*** host and remaining hosts:\n", tblock->name);
3374 for (host2 = host; host2 != NULL; host2 = host2->next)
3375 debug_printf(" %s [%s]\n", host2->name,
3376 (host2->address == NULL)? US"unset" : host2->address);
3381 /* This is for real. If the host is expired, we don't count it for
3382 hosts_max_retry. This ensures that all hosts must expire before an address
3383 is timed out, unless hosts_max_try_hardlimit (which protects against
3384 lunatic DNS configurations) is reached.
3386 If the host is not expired and we are about to hit the hosts_max_retry
3387 limit, check to see if there is a subsequent hosts with a different MX
3388 value. If so, make that the next host, and don't count this one. This is a
3389 heuristic to make sure that different MXs do get tried. With a normal kind
3390 of retry rule, they would get tried anyway when the earlier hosts were
3391 delayed, but if the domain has a "retry every time" type of rule - as is
3392 often used for the the very large ISPs, that won't happen. */
3397 /* Make a copy of the host if it is local to this invocation
3398 of the transport. */
3402 thost = store_get(sizeof(host_item));
3404 thost->name = string_copy(host->name);
3405 thost->address = string_copy(host->address);
3410 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
3414 debug_printf("hosts_max_try limit reached with this host\n");
3415 for (h = host; h != NULL; h = h->next)
3416 if (h->mx != host->mx) break;
3420 unexpired_hosts_tried--;
3421 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
3422 "and will be tried\n");
3426 /* Attempt the delivery. */
3428 total_hosts_tried++;
3429 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
3430 &message_defer, FALSE);
3433 OK => connection made, each address contains its result;
3434 message_defer is set for message-specific defers (when all
3435 recipients are marked defer)
3436 DEFER => there was a non-message-specific delivery problem;
3437 ERROR => there was a problem setting up the arguments for a filter,
3438 or there was a problem with expanding added headers
3441 /* If the result is not OK, there was a non-message-specific problem.
3442 If the result is DEFER, we need to write to the logs saying what happened
3443 for this particular host, except in the case of authentication and TLS
3444 failures, where the log has already been written. If all hosts defer a
3445 general message is written at the end. */
3447 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL &&
3448 first_addr->basic_errno != ERRNO_TLSFAILURE)
3449 write_logs(first_addr, host);
3451 #ifdef EXPERIMENTAL_EVENT
3453 deferred_event_raise(first_addr, host);
3456 /* If STARTTLS was accepted, but there was a failure in setting up the
3457 TLS session (usually a certificate screwup), and the host is not in
3458 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
3459 TLS forcibly turned off. We have to start from scratch with a new SMTP
3460 connection. That's why the retry is done from here, not from within
3461 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
3462 session, so the in-clear transmission after those errors, if permitted,
3463 happens inside smtp_deliver().] */
3467 && first_addr->basic_errno == ERRNO_TLSFAILURE
3468 && ob->tls_tempfail_tryclear
3469 && verify_check_given_host(&ob->hosts_require_tls, host) != OK
3472 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
3473 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
3474 first_addr = prepare_addresses(addrlist, host);
3475 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
3476 &message_defer, TRUE);
3477 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
3478 write_logs(first_addr, host);
3479 # ifdef EXPERIMENTAL_EVENT
3481 deferred_event_raise(first_addr, host);
3484 #endif /*SUPPORT_TLS*/
3487 /* Delivery attempt finished */
3489 rs = (rc == OK)? US"OK" : (rc == DEFER)? US"DEFER" : (rc == ERROR)?
3492 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
3493 message_id, host->name, host->address, addrlist->address,
3494 (addrlist->next == NULL)? "" : " (& others)", rs);
3496 /* Release serialization if set up */
3498 if (serialized) enq_end(serialize_key);
3500 /* If the result is DEFER, or if a host retry record is known to exist, we
3501 need to add an item to the retry chain for updating the retry database
3502 at the end of delivery. We only need to add the item to the top address,
3503 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
3504 for any other delivery attempts using the same address. (It is copied into
3505 the unusable tree at the outer level, so even if different address blocks
3506 contain the same address, it still won't get tried again.) */
3508 if (rc == DEFER || retry_host_key != NULL)
3510 int delete_flag = (rc != DEFER)? rf_delete : 0;
3511 if (retry_host_key == NULL)
3514 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3515 US"retry_include_ip_address", ob->retry_include_ip_address,
3516 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3517 incl_ip = TRUE; /* error; use most-specific retry record */
3519 retry_host_key = incl_ip ?
3520 string_sprintf("T:%S:%s%s", host->name, host->address, pistring) :
3521 string_sprintf("T:%S%s", host->name, pistring);
3524 /* If a delivery of another message over an existing SMTP connection
3525 yields DEFER, we do NOT set up retry data for the host. This covers the
3526 case when there are delays in routing the addresses in the second message
3527 that are so long that the server times out. This is alleviated by not
3528 routing addresses that previously had routing defers when handling an
3529 existing connection, but even so, this case may occur (e.g. if a
3530 previously happily routed address starts giving routing defers). If the
3531 host is genuinely down, another non-continued message delivery will
3532 notice it soon enough. */
3534 if (delete_flag != 0 || !continuing)
3535 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
3537 /* We may have tried an expired host, if its retry time has come; ensure
3538 the status reflects the expiry for the benefit of any other addresses. */
3542 host->status = (host_is_expired)?
3543 hstatus_unusable_expired : hstatus_unusable;
3544 host->why = hwhy_deferred;
3548 /* If message_defer is set (host was OK, but every recipient got deferred
3549 because of some message-specific problem), or if that had happened
3550 previously so that a message retry key exists, add an appropriate item
3551 to the retry chain. Note that if there was a message defer but now there is
3552 a host defer, the message defer record gets deleted. That seems perfectly
3553 reasonable. Also, stop the message from being remembered as waiting
3554 for specific hosts. */
3556 if (message_defer || retry_message_key != NULL)
3558 int delete_flag = message_defer? 0 : rf_delete;
3559 if (retry_message_key == NULL)
3562 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3563 US"retry_include_ip_address", ob->retry_include_ip_address,
3564 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3565 incl_ip = TRUE; /* error; use most-specific retry record */
3567 retry_message_key = incl_ip ?
3568 string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
3570 string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
3572 retry_add_item(addrlist, retry_message_key,
3573 rf_message | rf_host | delete_flag);
3574 update_waiting = FALSE;
3577 /* Any return other than DEFER (that is, OK or ERROR) means that the
3578 addresses have got their final statuses filled in for this host. In the OK
3579 case, see if any of them are deferred. */
3583 for (addr = addrlist; addr != NULL; addr = addr->next)
3585 if (addr->transport_return == DEFER)
3587 some_deferred = TRUE;
3593 /* If no addresses deferred or the result was ERROR, return. We do this for
3594 ERROR because a failing filter set-up or add_headers expansion is likely to
3595 fail for any host we try. */
3597 if (rc == ERROR || (rc == OK && !some_deferred))
3599 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3600 return TRUE; /* Each address has its status */
3603 /* If the result was DEFER or some individual addresses deferred, let
3604 the loop run to try other hosts with the deferred addresses, except for the
3605 case when we were trying to deliver down an existing channel and failed.
3606 Don't try any other hosts in this case. */
3608 if (continuing) break;
3610 /* If the whole delivery, or some individual addresses, were deferred and
3611 there are more hosts that could be tried, do not count this host towards
3612 the hosts_max_try limit if the age of the message is greater than the
3613 maximum retry time for this host. This means we may try try all hosts,
3614 ignoring the limit, when messages have been around for some time. This is
3615 important because if we don't try all hosts, the address will never time
3616 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
3618 if ((rc == DEFER || some_deferred) && nexthost != NULL)
3621 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
3623 if (retry != NULL && retry->rules != NULL)
3625 retry_rule *last_rule;
3626 for (last_rule = retry->rules;
3627 last_rule->next != NULL;
3628 last_rule = last_rule->next);
3629 timedout = time(NULL) - received_time > last_rule->timeout;
3631 else timedout = TRUE; /* No rule => timed out */
3635 unexpired_hosts_tried--;
3636 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
3637 "hosts_max_try (message older than host's retry time)\n");
3640 } /* End of loop for trying multiple hosts. */
3642 /* This is the end of the loop that repeats iff expired is TRUE and
3643 ob->delay_after_cutoff is FALSE. The second time round we will
3644 try those hosts that haven't been tried since the message arrived. */
3648 debug_printf("all IP addresses skipped or deferred at least one address\n");
3649 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
3650 debug_printf("retrying IP addresses not tried since message arrived\n");
3655 /* Get here if all IP addresses are skipped or defer at least one address. In
3656 MUA wrapper mode, this will happen only for connection or other non-message-
3657 specific failures. Force the delivery status for all addresses to FAIL. */
3661 for (addr = addrlist; addr != NULL; addr = addr->next)
3662 addr->transport_return = FAIL;
3666 /* In the normal, non-wrapper case, add a standard message to each deferred
3667 address if there hasn't been an error, that is, if it hasn't actually been
3668 tried this time. The variable "expired" will be FALSE if any deliveries were
3669 actually tried, or if there was at least one host that was not expired. That
3670 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
3671 a delivery has been tried, an error code will be set, and the failing of the
3672 message is handled by the retry code later.
3674 If queue_smtp is set, or this transport was called to send a subsequent message
3675 down an existing TCP/IP connection, and something caused the host not to be
3676 found, we end up here, but can detect these cases and handle them specially. */
3678 for (addr = addrlist; addr != NULL; addr = addr->next)
3680 /* If host is not NULL, it means that we stopped processing the host list
3681 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
3682 means we need to behave as if some hosts were skipped because their retry
3683 time had not come. Specifically, this prevents the address from timing out.
3684 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
3685 hosts were tried. */
3689 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
3692 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
3693 "hosts were tried\n");
3698 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
3699 setflag(addr, af_retry_skipped);
3703 if (queue_smtp) /* no deliveries attempted */
3705 addr->transport_return = DEFER;
3706 addr->basic_errno = 0;
3707 addr->message = US"SMTP delivery explicitly queued";
3710 else if (addr->transport_return == DEFER &&
3711 (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0) &&
3712 addr->message == NULL)
3714 addr->basic_errno = ERRNO_HRETRY;
3715 if (continue_hostname != NULL)
3717 addr->message = US"no host found for existing SMTP connection";
3721 setflag(addr, af_pass_message); /* This is not a security risk */
3722 addr->message = (ob->delay_after_cutoff)?
3723 US"retry time not reached for any host after a long failure period" :
3724 US"all hosts have been failing for a long time and were last tried "
3725 "after this message arrived";
3727 /* If we are already using fallback hosts, or there are no fallback hosts
3728 defined, convert the result to FAIL to cause a bounce. */
3730 if (addr->host_list == addr->fallback_hosts ||
3731 addr->fallback_hosts == NULL)
3732 addr->transport_return = FAIL;
3736 if (hosts_retry == hosts_total)
3737 addr->message = US"retry time not reached for any host";
3738 else if (hosts_fail == hosts_total)
3739 addr->message = US"all host address lookups failed permanently";
3740 else if (hosts_defer == hosts_total)
3741 addr->message = US"all host address lookups failed temporarily";
3742 else if (hosts_serial == hosts_total)
3743 addr->message = US"connection limit reached for all hosts";
3744 else if (hosts_fail+hosts_defer == hosts_total)
3745 addr->message = US"all host address lookups failed";
3746 else addr->message = US"some host address lookups failed and retry time "
3747 "not reached for other hosts or connection limit reached";
3752 /* Update the database which keeps information about which messages are waiting
3753 for which hosts to become available. For some message-specific errors, the
3754 update_waiting flag is turned off because we don't want follow-on deliveries in
3755 those cases. If this transport instance is explicitly limited to one message
3756 per connection then follow-on deliveries are not possible and there's no need
3757 to create/update the per-transport wait-<transport_name> database. */
3759 if (update_waiting && tblock->connection_max_messages != 1)
3760 transport_update_waiting(hostlist, tblock->name);
3764 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3766 return TRUE; /* Each address has its status */
3771 /* End of transport/smtp.c */
git://git.exim.org / exim.git / blob