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
254 ,NULL /* socks_proxy */
257 ,NULL, /* tls_certificate */
259 NULL, /* tls_privatekey */
260 NULL, /* tls_require_ciphers */
261 NULL, /* gnutls_require_kx */
262 NULL, /* gnutls_require_mac */
263 NULL, /* gnutls_require_proto */
265 US"system", /* tls_verify_certificates */
266 EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
267 /* tls_dh_min_bits */
268 TRUE, /* tls_tempfail_tryclear */
269 NULL, /* tls_verify_hosts */
270 US"*", /* tls_try_verify_hosts */
271 US"*" /* tls_verify_cert_hostnames */
274 ,NULL, /* dkim_canon */
275 NULL, /* dkim_domain */
276 NULL, /* dkim_private_key */
277 NULL, /* dkim_selector */
278 NULL, /* dkim_sign_headers */
279 NULL /* dkim_strict */
283 /* some DSN flags for use later */
285 static int rf_list[] = {rf_notify_never, rf_notify_success,
286 rf_notify_failure, rf_notify_delay };
288 static uschar *rf_names[] = { US"NEVER", US"SUCCESS", US"FAILURE", US"DELAY" };
294 static uschar *smtp_command; /* Points to last cmd for error messages */
295 static uschar *mail_command; /* Points to MAIL cmd for error messages */
296 static BOOL update_waiting; /* TRUE to update the "wait" database */
299 /*************************************************
300 * Setup entry point *
301 *************************************************/
303 /* This function is called when the transport is about to be used,
304 but before running it in a sub-process. It is used for two things:
306 (1) To set the fallback host list in addresses, when delivering.
307 (2) To pass back the interface, port, protocol, and other options, for use
308 during callout verification.
311 tblock pointer to the transport instance block
312 addrlist list of addresses about to be transported
313 tf if not NULL, pointer to block in which to return options
314 uid the uid that will be set (not used)
315 gid the gid that will be set (not used)
316 errmsg place for error message (not used)
318 Returns: OK always (FAIL, DEFER not used)
322 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
323 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
325 smtp_transport_options_block *ob =
326 (smtp_transport_options_block *)(tblock->options_block);
328 errmsg = errmsg; /* Keep picky compilers happy */
332 /* Pass back options if required. This interface is getting very messy. */
336 tf->interface = ob->interface;
338 tf->protocol = ob->protocol;
339 tf->hosts = ob->hosts;
340 tf->hosts_override = ob->hosts_override;
341 tf->hosts_randomize = ob->hosts_randomize;
342 tf->gethostbyname = ob->gethostbyname;
343 tf->qualify_single = ob->dns_qualify_single;
344 tf->search_parents = ob->dns_search_parents;
345 tf->helo_data = ob->helo_data;
348 /* Set the fallback host list for all the addresses that don't have fallback
349 host lists, provided that the local host wasn't present in the original host
352 if (!testflag(addrlist, af_local_host_removed))
354 for (; addrlist != NULL; addrlist = addrlist->next)
355 if (addrlist->fallback_hosts == NULL)
356 addrlist->fallback_hosts = ob->fallback_hostlist;
364 /*************************************************
365 * Initialization entry point *
366 *************************************************/
368 /* Called for each instance, after its options have been read, to
369 enable consistency checks to be done, or anything else that needs
372 Argument: pointer to the transport instance block
377 smtp_transport_init(transport_instance *tblock)
379 smtp_transport_options_block *ob =
380 (smtp_transport_options_block *)(tblock->options_block);
382 /* Retry_use_local_part defaults FALSE if unset */
384 if (tblock->retry_use_local_part == TRUE_UNSET)
385 tblock->retry_use_local_part = FALSE;
387 /* Set the default port according to the protocol */
389 if (ob->port == NULL)
390 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
391 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
393 /* Set up the setup entry point, to be called before subprocesses for this
396 tblock->setup = smtp_transport_setup;
398 /* Complain if any of the timeouts are zero. */
400 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
401 ob->final_timeout <= 0)
402 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
403 "command, data, or final timeout value is zero for %s transport",
406 /* If hosts_override is set and there are local hosts, set the global
407 flag that stops verify from showing router hosts. */
409 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
411 /* If there are any fallback hosts listed, build a chain of host items
412 for them, but do not do any lookups at this time. */
414 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
417 if ( ob->gnutls_require_kx
418 || ob->gnutls_require_mac
419 || ob->gnutls_require_proto)
420 log_write(0, LOG_MAIN, "WARNING: smtp transport options"
421 " gnutls_require_kx, gnutls_require_mac and gnutls_require_protocols"
430 /*************************************************
431 * Set delivery info into all active addresses *
432 *************************************************/
434 /* Only addresses whose status is >= PENDING are relevant. A lesser
435 status means that an address is not currently being processed.
438 addrlist points to a chain of addresses
439 errno_value to put in each address's errno field
440 msg to put in each address's message field
441 rc to put in each address's transport_return field
442 pass_message if TRUE, set the "pass message" flag in the address
443 host if set, mark addrs as having used this host
445 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
446 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
447 this particular type of timeout.
453 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
454 BOOL pass_message, host_item * host)
458 if (errno_value == ERRNO_CONNECTTIMEOUT)
460 errno_value = ETIMEDOUT;
461 orvalue = RTEF_CTOUT;
463 for (addr = addrlist; addr != NULL; addr = addr->next)
464 if (addr->transport_return >= PENDING)
466 addr->basic_errno = errno_value;
467 addr->more_errno |= orvalue;
471 if (pass_message) setflag(addr, af_pass_message);
473 addr->transport_return = rc;
475 addr->host_used = host;
481 /*************************************************
482 * Check an SMTP response *
483 *************************************************/
485 /* This function is given an errno code and the SMTP response buffer
486 to analyse, together with the host identification for generating messages. It
487 sets an appropriate message and puts the first digit of the response code into
488 the yield variable. If no response was actually read, a suitable digit is
492 host the current host, to get its name for messages
493 errno_value pointer to the errno value
494 more_errno from the top address for use with ERRNO_FILTER_FAIL
495 buffer the SMTP response buffer
496 yield where to put a one-digit SMTP response code
497 message where to put an errror message
498 pass_message set TRUE if message is an SMTP response
500 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
504 check_response(host_item *host, int *errno_value, int more_errno,
505 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
509 if (smtp_use_pipelining &&
510 (Ustrcmp(smtp_command, "MAIL") == 0 ||
511 Ustrcmp(smtp_command, "RCPT") == 0 ||
512 Ustrcmp(smtp_command, "DATA") == 0))
515 *yield = '4'; /* Default setting is to give a temporary error */
517 /* Handle response timeout */
519 if (*errno_value == ETIMEDOUT)
521 *message = US string_sprintf("SMTP timeout after %s%s",
523 if (transport_count > 0)
524 *message = US string_sprintf("%s (%d bytes written)", *message,
529 /* Handle malformed SMTP response */
531 if (*errno_value == ERRNO_SMTPFORMAT)
533 const uschar *malfresp = string_printing(buffer);
534 while (isspace(*malfresp)) malfresp++;
535 *message = *malfresp == 0
536 ? string_sprintf("Malformed SMTP reply (an empty line) "
537 "in response to %s%s", pl, smtp_command)
538 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
539 pl, smtp_command, malfresp);
543 /* Handle a failed filter process error; can't send QUIT as we mustn't
546 if (*errno_value == ERRNO_FILTER_FAIL)
548 *message = US string_sprintf("transport filter process failed (%d)%s",
550 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
554 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
557 if (*errno_value == ERRNO_CHHEADER_FAIL)
560 US string_sprintf("failed to expand headers_add or headers_remove: %s",
561 expand_string_message);
565 /* Handle failure to write a complete data block */
567 if (*errno_value == ERRNO_WRITEINCOMPLETE)
569 *message = US string_sprintf("failed to write a data block");
573 /* Handle error responses from the remote mailer. */
577 const uschar *s = string_printing(buffer);
578 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
579 "%s", pl, smtp_command, s);
580 *pass_message = TRUE;
585 /* No data was read. If there is no errno, this must be the EOF (i.e.
586 connection closed) case, which causes deferral. An explicit connection reset
587 error has the same effect. Otherwise, put the host's identity in the message,
588 leaving the errno value to be interpreted as well. In all cases, we have to
589 assume the connection is now dead. */
591 if (*errno_value == 0 || *errno_value == ECONNRESET)
593 *errno_value = ERRNO_SMTPCLOSED;
594 *message = US string_sprintf("Remote host closed connection "
595 "in response to %s%s", pl, smtp_command);
597 else *message = US string_sprintf("%s [%s]", host->name, host->address);
604 /*************************************************
605 * Write error message to logs *
606 *************************************************/
608 /* This writes to the main log and to the message log.
611 addr the address item containing error information
612 host the current host
618 write_logs(address_item *addr, host_item *host)
620 uschar * message = string_sprintf("H=%s [%s]", host->name, host->address);
624 message = string_sprintf("%s: %s", message, addr->message);
625 if (addr->basic_errno > 0)
626 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
627 log_write(0, LOG_MAIN, "%s", message);
628 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
632 if (log_extra_selector & LX_outgoing_port)
633 message = string_sprintf("%s:%d", message,
634 host->port == PORT_NONE ? 25 : host->port);
635 log_write(0, LOG_MAIN, "%s %s", message, strerror(addr->basic_errno));
636 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), message,
637 strerror(addr->basic_errno));
642 msglog_line(host_item * host, uschar * message)
644 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
645 host->name, host->address, message);
650 #ifdef EXPERIMENTAL_EVENT
651 /*************************************************
652 * Post-defer action *
653 *************************************************/
655 /* This expands an arbitrary per-transport string.
656 It might, for example, be used to write to the database log.
659 addr the address item containing error information
660 host the current host
666 deferred_event_raise(address_item *addr, host_item *host)
668 uschar * action = addr->transport->event_action;
669 const uschar * save_domain;
675 save_domain = deliver_domain;
676 save_local = deliver_localpart;
678 /*XXX would ip & port already be set up? */
679 deliver_host_address = string_copy(host->address);
680 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
681 event_defer_errno = addr->basic_errno;
683 router_name = addr->router->name;
684 transport_name = addr->transport->name;
685 deliver_domain = addr->domain;
686 deliver_localpart = addr->local_part;
688 (void) event_raise(action, US"msg:host:defer",
690 ? addr->basic_errno > 0
691 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
692 : string_copy(addr->message)
693 : addr->basic_errno > 0
694 ? string_copy(US strerror(addr->basic_errno))
697 deliver_localpart = save_local;
698 deliver_domain = save_domain;
699 router_name = transport_name = NULL;
703 /*************************************************
704 * Synchronize SMTP responses *
705 *************************************************/
707 /* This function is called from smtp_deliver() to receive SMTP responses from
708 the server, and match them up with the commands to which they relate. When
709 PIPELINING is not in use, this function is called after every command, and is
710 therefore somewhat over-engineered, but it is simpler to use a single scheme
711 that works both with and without PIPELINING instead of having two separate sets
714 The set of commands that are buffered up with pipelining may start with MAIL
715 and may end with DATA; in between are RCPT commands that correspond to the
716 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
717 etc.) are never buffered.
719 Errors after MAIL or DATA abort the whole process leaving the response in the
720 buffer. After MAIL, pending responses are flushed, and the original command is
721 re-instated in big_buffer for error messages. For RCPT commands, the remote is
722 permitted to reject some recipient addresses while accepting others. However
723 certain errors clearly abort the whole process. Set the value in
724 transport_return to PENDING_OK if the address is accepted. If there is a
725 subsequent general error, it will get reset accordingly. If not, it will get
726 converted to OK at the end.
729 addrlist the complete address list
730 include_affixes TRUE if affixes include in RCPT
731 sync_addr ptr to the ptr of the one to start scanning at (updated)
732 host the host we are connected to
733 count the number of responses to read
735 include_sender true if 4xx retry is to include the sender it its key
736 pending_MAIL true if the first response is for MAIL
737 pending_DATA 0 if last command sent was not DATA
738 +1 if previously had a good recipient
739 -1 if not previously had a good recipient
740 inblock incoming SMTP block
741 timeout timeout value
742 buffer buffer for reading response
743 buffsize size of buffer
745 Returns: 3 if at least one address had 2xx and one had 5xx
746 2 if at least one address had 5xx but none had 2xx
747 1 if at least one host had a 2xx response, but none had 5xx
748 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
749 -1 timeout while reading RCPT response
750 -2 I/O or other non-response error for RCPT
751 -3 DATA or MAIL failed - errno and buffer set
755 sync_responses(address_item *addrlist, BOOL include_affixes,
756 address_item **sync_addr, host_item *host, int count,
757 BOOL address_retry_include_sender, BOOL pending_MAIL,
758 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
761 address_item *addr = *sync_addr;
764 /* Handle the response for a MAIL command. On error, reinstate the original
765 command in big_buffer for error message use, and flush any further pending
766 responses before returning, except after I/O errors and timeouts. */
771 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
773 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
774 if (errno == 0 && buffer[0] != 0)
776 uschar flushbuffer[4096];
778 if (buffer[0] == '4')
780 save_errno = ERRNO_MAIL4XX;
781 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
785 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
787 && (errno != 0 || flushbuffer[0] == 0))
793 if (pending_DATA) count--; /* Number of RCPT responses to come */
794 while (count-- > 0) /* Mark any pending addrs with the host used */
796 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
797 addr->host_used = host;
804 if (pending_DATA) count--; /* Number of RCPT responses to come */
806 /* Read and handle the required number of RCPT responses, matching each one up
807 with an address by scanning for the next address whose status is PENDING_DEFER.
812 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
814 /* The address was accepted */
815 addr->host_used = host;
817 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
820 addr->transport_return = PENDING_OK;
822 /* If af_dr_retry_exists is set, there was a routing delay on this address;
823 ensure that any address-specific retry record is expunged. We do this both
824 for the basic key and for the version that also includes the sender. */
826 if (testflag(addr, af_dr_retry_exists))
828 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
830 retry_add_item(addr, altkey, rf_delete);
831 retry_add_item(addr, addr->address_retry_key, rf_delete);
835 /* Timeout while reading the response */
837 else if (errno == ETIMEDOUT)
839 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
840 transport_rcpt_address(addr, include_affixes));
841 set_errno(addrlist, ETIMEDOUT, message, DEFER, FALSE, NULL);
842 retry_add_item(addr, addr->address_retry_key, 0);
843 update_waiting = FALSE;
847 /* Handle other errors in obtaining an SMTP response by returning -1. This
848 will cause all the addresses to be deferred. Restore the SMTP command in
849 big_buffer for which we are checking the response, so the error message
852 else if (errno != 0 || buffer[0] == 0)
854 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
855 transport_rcpt_address(addr, include_affixes));
859 /* Handle SMTP permanent and temporary response codes. */
864 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
865 "%s", transport_rcpt_address(addr, include_affixes),
866 string_printing(buffer));
867 setflag(addr, af_pass_message);
868 msglog_line(host, addr->message);
870 /* The response was 5xx */
872 if (buffer[0] == '5')
874 addr->transport_return = FAIL;
878 /* The response was 4xx */
882 addr->transport_return = DEFER;
883 addr->basic_errno = ERRNO_RCPT4XX;
884 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
886 /* Log temporary errors if there are more hosts to be tried.
887 If not, log this last one in the == line. */
890 log_write(0, LOG_MAIN, "H=%s [%s]: %s", host->name, host->address, addr->message);
892 /* Do not put this message on the list of those waiting for specific
893 hosts, as otherwise it is likely to be tried too often. */
895 update_waiting = FALSE;
897 /* Add a retry item for the address so that it doesn't get tried again
898 too soon. If address_retry_include_sender is true, add the sender address
901 if (address_retry_include_sender)
903 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
905 retry_add_item(addr, altkey, 0);
907 else retry_add_item(addr, addr->address_retry_key, 0);
910 } /* Loop for next RCPT response */
912 /* Update where to start at for the next block of responses, unless we
913 have already handled all the addresses. */
915 if (addr != NULL) *sync_addr = addr->next;
917 /* Handle a response to DATA. If we have not had any good recipients, either
918 previously or in this block, the response is ignored. */
920 if (pending_DATA != 0 &&
921 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
926 if (pending_DATA > 0 || (yield & 1) != 0)
928 if (errno == 0 && buffer[0] == '4')
930 errno = ERRNO_DATA4XX;
931 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
935 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
936 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
937 "is in use and there were no good recipients\n", msg);
940 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
941 present) received 3xx. If any RCPTs were handled and yielded anything other
942 than 4xx, yield will be set non-zero. */
949 /* Do the client side of smtp-level authentication */
952 buffer EHLO response from server (gets overwritten)
953 addrlist chain of potential addresses to deliver
954 host host to deliver to
956 ibp, obp comms channel control blocks
959 OK Success, or failed (but not required): global "smtp_authenticated" set
960 DEFER Failed authentication (and was required)
961 ERROR Internal problem
963 FAIL_SEND Failed communications - transmit
968 smtp_auth(uschar *buffer, unsigned bufsize, address_item *addrlist, host_item *host,
969 smtp_transport_options_block *ob, BOOL is_esmtp,
970 smtp_inblock *ibp, smtp_outblock *obp)
973 uschar *fail_reason = US"server did not advertise AUTH support";
975 smtp_authenticated = FALSE;
976 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
977 require_auth = verify_check_given_host(&ob->hosts_require_auth, host);
979 if (is_esmtp && !regex_AUTH) regex_AUTH =
980 regex_must_compile(US"\\n250[\\s\\-]AUTH\\s+([\\-\\w\\s]+)(?:\\n|$)",
983 if (is_esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
985 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
986 expand_nmax = -1; /* reset */
988 /* Must not do this check until after we have saved the result of the
989 regex match above. */
991 if (require_auth == OK ||
992 verify_check_given_host(&ob->hosts_try_auth, host) == OK)
995 fail_reason = US"no common mechanisms were found";
997 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
999 /* Scan the configured authenticators looking for one which is configured
1000 for use as a client, which is not suppressed by client_condition, and
1001 whose name matches an authentication mechanism supported by the server.
1002 If one is found, attempt to authenticate by calling its client function.
1005 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1009 (au->client_condition != NULL &&
1010 !expand_check_condition(au->client_condition, au->name,
1011 US"client authenticator")))
1013 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1015 (au->client)? "client_condition is false" :
1016 "not configured as a client");
1020 /* Loop to scan supported server mechanisms */
1025 int len = Ustrlen(au->public_name);
1026 while (isspace(*p)) p++;
1028 if (strncmpic(au->public_name, p, len) != 0 ||
1029 (p[len] != 0 && !isspace(p[len])))
1031 while (*p != 0 && !isspace(*p)) p++;
1035 /* Found data for a listed mechanism. Call its client entry. Set
1036 a flag in the outblock so that data is overwritten after sending so
1037 that reflections don't show it. */
1039 fail_reason = US"authentication attempt(s) failed";
1040 obp->authenticating = TRUE;
1041 rc = (au->info->clientcode)(au, ibp, obp,
1042 ob->command_timeout, buffer, bufsize);
1043 obp->authenticating = FALSE;
1044 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1047 /* A temporary authentication failure must hold up delivery to
1048 this host. After a permanent authentication failure, we carry on
1049 to try other authentication methods. If all fail hard, try to
1050 deliver the message unauthenticated unless require_auth was set. */
1055 smtp_authenticated = TRUE; /* stops the outer loop */
1056 client_authenticator = au->name;
1057 if (au->set_client_id != NULL)
1058 client_authenticated_id = expand_string(au->set_client_id);
1061 /* Failure after writing a command */
1066 /* Failure after reading a response */
1069 if (errno != 0 || buffer[0] != '5') return FAIL;
1070 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1071 au->name, host->name, host->address, buffer);
1074 /* Failure by some other means. In effect, the authenticator
1075 decided it wasn't prepared to handle this case. Typically this
1076 is the result of "fail" in an expansion string. Do we need to
1077 log anything here? Feb 2006: a message is now put in the buffer
1078 if logging is required. */
1082 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1083 "authentication H=%s [%s] %s", au->name, host->name,
1084 host->address, buffer);
1087 /* Internal problem, message in buffer. */
1090 set_errno(addrlist, ERRNO_AUTHPROB, string_copy(buffer),
1091 DEFER, FALSE, NULL);
1095 break; /* If not authenticated, try next authenticator */
1096 } /* Loop for scanning supported server mechanisms */
1097 } /* Loop for further authenticators */
1101 /* If we haven't authenticated, but are required to, give up. */
1103 if (require_auth == OK && !smtp_authenticated)
1105 set_errno(addrlist, ERRNO_AUTHFAIL,
1106 string_sprintf("authentication required but %s", fail_reason), DEFER,
1115 /* Construct AUTH appendix string for MAIL TO */
1118 buffer to build string
1119 addrlist chain of potential addresses to deliver
1120 ob transport options
1122 Globals smtp_authenticated
1123 client_authenticated_sender
1124 Return True on error, otherwise buffer has (possibly empty) terminated string
1128 smtp_mail_auth_str(uschar *buffer, unsigned bufsize, address_item *addrlist,
1129 smtp_transport_options_block *ob)
1131 uschar *local_authenticated_sender = authenticated_sender;
1134 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n", authenticated_sender, ob->authenticated_sender, smtp_authenticated?"Y":"N");
1137 if (ob->authenticated_sender != NULL)
1139 uschar *new = expand_string(ob->authenticated_sender);
1142 if (!expand_string_forcedfail)
1144 uschar *message = string_sprintf("failed to expand "
1145 "authenticated_sender: %s", expand_string_message);
1146 set_errno(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, NULL);
1150 else if (new[0] != 0) local_authenticated_sender = new;
1153 /* Add the authenticated sender address if present */
1155 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1156 local_authenticated_sender != NULL)
1158 string_format(buffer, bufsize, " AUTH=%s",
1159 auth_xtextencode(local_authenticated_sender,
1160 Ustrlen(local_authenticated_sender)));
1161 client_authenticated_sender = string_copy(local_authenticated_sender);
1171 #ifdef EXPERIMENTAL_DANE
1173 tlsa_lookup(const host_item * host, dns_answer * dnsa,
1174 BOOL dane_required, BOOL * dane)
1176 /* move this out to host.c given the similarity to dns_lookup() ? */
1178 const uschar * fullname = buffer;
1180 /* TLSA lookup string */
1181 (void)sprintf(CS buffer, "_%d._tcp.%.256s", host->port, host->name);
1183 switch (dns_lookup(dnsa, buffer, T_TLSA, &fullname))
1186 return DEFER; /* just defer this TLS'd conn */
1192 log_write(0, LOG_MAIN, "DANE error: TLSA lookup failed");
1198 if (!dns_is_secure(dnsa))
1200 log_write(0, LOG_MAIN, "DANE error: TLSA lookup not DNSSEC");
1212 typedef struct smtp_compare_s
1214 uschar *current_sender_address;
1215 struct transport_instance *tblock;
1219 Create a unique string that identifies this message, it is based on
1220 sender_address, helo_data and tls_certificate if enabled. */
1223 smtp_local_identity(uschar * sender, struct transport_instance * tblock)
1225 address_item * addr1;
1226 uschar * if1 = US"";
1227 uschar * helo1 = US"";
1229 uschar * tlsc1 = US"";
1231 uschar * save_sender_address = sender_address;
1232 uschar * local_identity = NULL;
1233 smtp_transport_options_block * ob =
1234 (smtp_transport_options_block *)tblock->options_block;
1236 sender_address = sender;
1238 addr1 = deliver_make_addr (sender, TRUE);
1239 deliver_set_expansions(addr1);
1242 if1 = expand_string(ob->interface);
1245 helo1 = expand_string(ob->helo_data);
1248 if (ob->tls_certificate)
1249 tlsc1 = expand_string(ob->tls_certificate);
1250 local_identity = string_sprintf ("%s^%s^%s", if1, helo1, tlsc1);
1252 local_identity = string_sprintf ("%s^%s", if1, helo1);
1255 deliver_set_expansions(NULL);
1256 sender_address = save_sender_address;
1258 return local_identity;
1263 /* This routine is a callback that is called from transport_check_waiting.
1264 This function will evaluate the incoming message versus the previous
1265 message. If the incoming message is using a different local identity then
1266 we will veto this new message. */
1269 smtp_are_same_identities(uschar * message_id, smtp_compare_t * s_compare)
1271 uschar * save_sender_address = sender_address;
1272 uschar * current_local_identity =
1273 smtp_local_identity(s_compare->current_sender_address, s_compare->tblock);
1274 uschar * new_sender_address = deliver_get_sender_address(message_id);
1275 uschar * message_local_identity =
1276 smtp_local_identity(new_sender_address, s_compare->tblock);
1278 sender_address = save_sender_address;
1280 return Ustrcmp(current_local_identity, message_local_identity) == 0;
1285 /*************************************************
1286 * Deliver address list to given host *
1287 *************************************************/
1289 /* If continue_hostname is not null, we get here only when continuing to
1290 deliver down an existing channel. The channel was passed as the standard
1291 input. TLS is never active on a passed channel; the previous process always
1292 closes it down before passing the connection on.
1294 Otherwise, we have to make a connection to the remote host, and do the
1295 initial protocol exchange.
1297 When running as an MUA wrapper, if the sender or any recipient is rejected,
1298 temporarily or permanently, we force failure for all recipients.
1301 addrlist chain of potential addresses to deliver; only those whose
1302 transport_return field is set to PENDING_DEFER are currently
1303 being processed; others should be skipped - they have either
1304 been delivered to an earlier host or IP address, or been
1305 failed by one of them.
1306 host host to deliver to
1307 host_af AF_INET or AF_INET6
1308 port default TCP/IP port to use, in host byte order
1309 interface interface to bind to, or NULL
1310 tblock transport instance block
1311 message_defer set TRUE if yield is OK, but all addresses were deferred
1312 because of a non-recipient, non-host failure, that is, a
1313 4xx response to MAIL FROM, DATA, or ".". This is a defer
1314 that is specific to the message.
1315 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1316 a second attempt after TLS initialization fails
1318 Returns: OK - the connection was made and the delivery attempted;
1319 the result for each address is in its data block.
1320 DEFER - the connection could not be made, or something failed
1321 while setting up the SMTP session, or there was a
1322 non-message-specific error, such as a timeout.
1323 ERROR - a filter command is specified for this transport,
1324 and there was a problem setting it up; OR helo_data
1325 or add_headers or authenticated_sender is specified
1326 for this transport, and the string failed to expand
1330 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
1331 uschar *interface, transport_instance *tblock,
1332 BOOL *message_defer, BOOL suppress_tls)
1335 address_item *sync_addr;
1336 address_item *first_addr = addrlist;
1341 time_t start_delivery_time = time(NULL);
1342 smtp_transport_options_block *ob =
1343 (smtp_transport_options_block *)(tblock->options_block);
1344 BOOL lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
1345 BOOL smtps = strcmpic(ob->protocol, US"smtps") == 0;
1347 BOOL send_rset = TRUE;
1348 BOOL send_quit = TRUE;
1349 BOOL setting_up = TRUE;
1350 BOOL completed_address = FALSE;
1353 BOOL pass_message = FALSE;
1354 #ifndef DISABLE_PRDR
1355 BOOL prdr_offered = FALSE;
1358 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 && (rc = tlsa_lookup(host, &tlsa_dnsa, dane_required, &dane)) != OK
1460 else if (dane_required)
1462 log_write(0, LOG_MAIN, "DANE error: %s lookup not DNSSEC", host->name);
1467 ob->tls_tempfail_tryclear = FALSE;
1471 /* Expand the greeting message while waiting for the initial response. (Makes
1472 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1473 delayed till here so that $sending_interface and $sending_port are set. */
1475 helo_data = expand_string(ob->helo_data);
1477 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1478 is nevertheless a reasonably clean way of programming this kind of logic,
1479 where you want to escape on any error. */
1483 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1484 ob->command_timeout)) goto RESPONSE_FAILED;
1486 #ifdef EXPERIMENTAL_EVENT
1489 lookup_dnssec_authenticated = host->dnssec==DS_YES ? US"yes"
1490 : host->dnssec==DS_NO ? US"no" : NULL;
1491 s = event_raise(tblock->event_action, US"smtp:connect", buffer);
1494 set_errno(addrlist, ERRNO_EXPANDFAIL,
1495 string_sprintf("deferred by smtp:connect event expansion: %s", s),
1496 DEFER, FALSE, NULL);
1503 /* Now check if the helo_data expansion went well, and sign off cleanly if
1506 if (helo_data == NULL)
1508 uschar *message = string_sprintf("failed to expand helo_data: %s",
1509 expand_string_message);
1510 set_errno(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, NULL);
1516 /** Debugging without sending a message
1517 addrlist->transport_return = DEFER;
1521 /* Errors that occur after this point follow an SMTP command, which is
1522 left in big_buffer by smtp_write_command() for use in error messages. */
1524 smtp_command = big_buffer;
1526 /* Tell the remote who we are...
1528 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1529 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1530 greeting is of this form. The assumption was that the far end supports it
1531 properly... but experience shows that there are some that give 5xx responses,
1532 even though the banner includes "ESMTP" (there's a bloody-minded one that
1533 says "ESMTP not spoken here"). Cope with that case.
1535 September 2000: Time has passed, and it seems reasonable now to always send
1536 EHLO at the start. It is also convenient to make the change while installing
1539 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1540 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1541 would be no way to send out the mails, so there is now a host list
1542 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1543 PIPELINING problem as well. Maybe it can also be useful to cure other
1544 problems with broken servers.
1546 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1547 Then somebody tried it with a Microsoft mailer... It seems that all other
1548 mailers use upper case for some reason (the RFC is quite clear about case
1549 independence) so, for peace of mind, I gave in. */
1551 esmtp = verify_check_given_host(&ob->hosts_avoid_esmtp, host) != OK;
1553 /* Alas; be careful, since this goto is not an error-out, so conceivably
1554 we might set data between here and the target which we assume to exist
1555 and be usable. I can see this coming back to bite us. */
1560 suppress_tls = FALSE;
1561 ob->tls_tempfail_tryclear = FALSE;
1562 smtp_command = US"SSL-on-connect";
1569 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1570 lmtp? "LHLO" : "EHLO", helo_data) < 0)
1572 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1573 ob->command_timeout))
1575 if (errno != 0 || buffer[0] == 0 || lmtp) goto RESPONSE_FAILED;
1582 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1587 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1589 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1590 ob->command_timeout)) goto RESPONSE_FAILED;
1593 /* Set IGNOREQUOTA if the response to LHLO specifies support and the
1594 lmtp_ignore_quota option was set. */
1596 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1597 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1598 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1600 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1603 tls_offered = esmtp &&
1604 pcre_exec(regex_STARTTLS, NULL, CS buffer, Ustrlen(buffer), 0,
1605 PCRE_EOPT, NULL, 0) >= 0;
1608 #ifndef DISABLE_PRDR
1609 prdr_offered = esmtp
1610 && pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(buffer), 0,
1611 PCRE_EOPT, NULL, 0) >= 0
1612 && verify_check_given_host(&ob->hosts_try_prdr, host) == OK;
1615 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1619 /* For continuing deliveries down the same channel, the socket is the standard
1620 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1621 below). Set up the pointer to where subsequent commands will be left, for
1622 error messages. Note that smtp_use_size and smtp_use_pipelining will have been
1623 set from the command line if they were set in the process that passed the
1628 inblock.sock = outblock.sock = fileno(stdin);
1629 smtp_command = big_buffer;
1630 host->port = port; /* Record the port that was used */
1633 /* If TLS is available on this connection, whether continued or not, attempt to
1634 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1635 send another EHLO - the server may give a different answer in secure mode. We
1636 use a separate buffer for reading the response to STARTTLS so that if it is
1637 negative, the original EHLO data is available for subsequent analysis, should
1638 the client not be required to use TLS. If the response is bad, copy the buffer
1639 for error analysis. */
1644 && verify_check_given_host(&ob->hosts_avoid_tls, host) != OK)
1646 uschar buffer2[4096];
1647 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1650 /* If there is an I/O error, transmission of this message is deferred. If
1651 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1652 false, we also defer. However, if there is a temporary rejection of STARTTLS
1653 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1654 STARTTLS, we carry on. This means we will try to send the message in clear,
1655 unless the host is in hosts_require_tls (tested below). */
1657 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1658 ob->command_timeout))
1660 if (errno != 0 || buffer2[0] == 0 ||
1661 (buffer2[0] == '4' && !ob->tls_tempfail_tryclear))
1663 Ustrncpy(buffer, buffer2, sizeof(buffer));
1664 goto RESPONSE_FAILED;
1668 /* STARTTLS accepted: try to negotiate a TLS session. */
1673 int rc = tls_client_start(inblock.sock, host, addrlist, tblock
1674 # ifdef EXPERIMENTAL_DANE
1675 , dane ? &tlsa_dnsa : NULL
1679 /* TLS negotiation failed; give an error. From outside, this function may
1680 be called again to try in clear on a new connection, if the options permit
1681 it for this host. */
1685 # ifdef EXPERIMENTAL_DANE
1686 if (rc == DEFER && dane && !dane_required)
1688 log_write(0, LOG_MAIN, "DANE attempt failed;"
1689 " trying CA-root TLS to %s [%s] (not in hosts_require_dane)",
1690 host->name, host->address);
1696 save_errno = ERRNO_TLSFAILURE;
1697 message = US"failure while setting up TLS session";
1702 /* TLS session is set up */
1704 for (addr = addrlist; addr != NULL; addr = addr->next)
1705 if (addr->transport_return == PENDING_DEFER)
1707 addr->cipher = tls_out.cipher;
1708 addr->ourcert = tls_out.ourcert;
1709 addr->peercert = tls_out.peercert;
1710 addr->peerdn = tls_out.peerdn;
1711 addr->ocsp = tls_out.ocsp;
1716 /* if smtps, we'll have smtp_command set to something else; always safe to
1718 smtp_command = big_buffer;
1720 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1721 helo_data is null, we are dealing with a connection that was passed from
1722 another process, and so we won't have expanded helo_data above. We have to
1723 expand it here. $sending_ip_address and $sending_port are set up right at the
1724 start of the Exim process (in exim.c). */
1726 if (tls_out.active >= 0)
1729 if (helo_data == NULL)
1731 helo_data = expand_string(ob->helo_data);
1732 if (helo_data == NULL)
1734 uschar *message = string_sprintf("failed to expand helo_data: %s",
1735 expand_string_message);
1736 set_errno(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, NULL);
1742 /* For SMTPS we need to wait for the initial OK response. */
1745 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1746 ob->command_timeout)) goto RESPONSE_FAILED;
1750 greeting_cmd = "EHLO";
1753 greeting_cmd = "HELO";
1755 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1758 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1759 lmtp? "LHLO" : greeting_cmd, helo_data) < 0)
1761 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1762 ob->command_timeout))
1763 goto RESPONSE_FAILED;
1766 /* If the host is required to use a secure channel, ensure that we
1770 # ifdef EXPERIMENTAL_DANE
1773 verify_check_given_host(&ob->hosts_require_tls, host) == OK
1776 save_errno = ERRNO_TLSREQUIRED;
1777 message = string_sprintf("a TLS session is required, but %s",
1778 tls_offered? "an attempt to start TLS failed" :
1779 "the server did not offer TLS support");
1782 #endif /*SUPPORT_TLS*/
1784 /* If TLS is active, we have just started it up and re-done the EHLO command,
1785 so its response needs to be analyzed. If TLS is not active and this is a
1786 continued session down a previously-used socket, we haven't just done EHLO, so
1789 if (continue_hostname == NULL
1791 || tls_out.active >= 0
1795 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
1796 lmtp_ignore_quota option was set. */
1798 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1799 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1800 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1802 /* If the response to EHLO specified support for the SIZE parameter, note
1803 this, provided size_addition is non-negative. */
1805 smtp_use_size = esmtp && ob->size_addition >= 0 &&
1806 pcre_exec(regex_SIZE, NULL, CS buffer, Ustrlen(CS buffer), 0,
1807 PCRE_EOPT, NULL, 0) >= 0;
1809 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
1810 the current host, esmtp will be false, so PIPELINING can never be used. If
1811 the current host matches hosts_avoid_pipelining, don't do it. */
1813 smtp_use_pipelining = esmtp
1814 && verify_check_given_host(&ob->hosts_avoid_pipelining, host) != OK
1815 && pcre_exec(regex_PIPELINING, NULL, CS buffer, Ustrlen(CS buffer), 0,
1816 PCRE_EOPT, NULL, 0) >= 0;
1818 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
1819 smtp_use_pipelining? "" : "not ");
1821 #ifndef DISABLE_PRDR
1822 prdr_offered = esmtp
1823 && pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(CS buffer), 0,
1824 PCRE_EOPT, NULL, 0) >= 0
1825 && verify_check_given_host(&ob->hosts_try_prdr, host) == OK;
1828 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1831 /* Note if the server supports DSN */
1832 smtp_use_dsn = esmtp && pcre_exec(regex_DSN, NULL, CS buffer, (int)Ustrlen(CS buffer), 0,
1833 PCRE_EOPT, NULL, 0) >= 0;
1834 DEBUG(D_transport) debug_printf("use_dsn=%d\n", smtp_use_dsn);
1836 /* Note if the response to EHLO specifies support for the AUTH extension.
1837 If it has, check that this host is one we want to authenticate to, and do
1838 the business. The host name and address must be available when the
1839 authenticator's client driver is running. */
1841 switch (yield = smtp_auth(buffer, sizeof(buffer), addrlist, host,
1842 ob, esmtp, &inblock, &outblock))
1844 default: goto SEND_QUIT;
1846 case FAIL_SEND: goto SEND_FAILED;
1847 case FAIL: goto RESPONSE_FAILED;
1851 /* The setting up of the SMTP call is now complete. Any subsequent errors are
1852 message-specific. */
1856 /* If there is a filter command specified for this transport, we can now
1857 set it up. This cannot be done until the identify of the host is known. */
1859 if (tblock->filter_command != NULL)
1863 sprintf(CS buffer, "%.50s transport", tblock->name);
1864 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
1865 TRUE, DEFER, addrlist, buffer, NULL);
1866 transport_filter_timeout = tblock->filter_timeout;
1868 /* On failure, copy the error to all addresses, abandon the SMTP call, and
1873 set_errno(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
1881 /* For messages that have more than the maximum number of envelope recipients,
1882 we want to send several transactions down the same SMTP connection. (See
1883 comments in deliver.c as to how this reconciles, heuristically, with
1884 remote_max_parallel.) This optimization was added to Exim after the following
1885 code was already working. The simplest way to put it in without disturbing the
1886 code was to use a goto to jump back to this point when there is another
1887 transaction to handle. */
1890 sync_addr = first_addr;
1894 completed_address = FALSE;
1897 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
1898 qualification, send it, adding something to the message size to allow for
1899 imprecision and things that get added en route. Exim keeps the number of lines
1900 in a message, so we can give an accurate value for the original message, but we
1901 need some additional to handle added headers. (Double "." characters don't get
1902 included in the count.) */
1909 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
1913 #ifndef DISABLE_PRDR
1914 prdr_active = FALSE;
1917 for (addr = first_addr; addr; addr = addr->next)
1918 if (addr->transport_return == PENDING_DEFER)
1920 for (addr = addr->next; addr; addr = addr->next)
1921 if (addr->transport_return == PENDING_DEFER)
1922 { /* at least two recipients to send */
1924 sprintf(CS p, " PRDR"); p += 5;
1932 /* check if all addresses have lasthop flag */
1933 /* do not send RET and ENVID if true */
1934 dsn_all_lasthop = TRUE;
1935 for (addr = first_addr;
1936 address_count < max_rcpt && addr != NULL;
1938 if ((addr->dsn_flags & rf_dsnlasthop) != 1)
1939 dsn_all_lasthop = FALSE;
1941 /* Add any DSN flags to the mail command */
1943 if ((smtp_use_dsn) && (dsn_all_lasthop == FALSE))
1945 if (dsn_ret == dsn_ret_hdrs)
1947 Ustrcpy(p, " RET=HDRS");
1950 else if (dsn_ret == dsn_ret_full)
1952 Ustrcpy(p, " RET=FULL");
1955 if (dsn_envid != NULL)
1957 string_format(p, sizeof(buffer) - (p-buffer), " ENVID=%s", dsn_envid);
1962 /* If an authenticated_sender override has been specified for this transport
1963 instance, expand it. If the expansion is forced to fail, and there was already
1964 an authenticated_sender for this message, the original value will be used.
1965 Other expansion failures are serious. An empty result is ignored, but there is
1966 otherwise no check - this feature is expected to be used with LMTP and other
1967 cases where non-standard addresses (e.g. without domains) might be required. */
1969 if (smtp_mail_auth_str(p, sizeof(buffer) - (p-buffer), addrlist, ob))
1975 /* From here until we send the DATA command, we can make use of PIPELINING
1976 if the server host supports it. The code has to be able to check the responses
1977 at any point, for when the buffer fills up, so we write it totally generally.
1978 When PIPELINING is off, each command written reports that it has flushed the
1981 pending_MAIL = TRUE; /* The block starts with MAIL */
1983 rc = smtp_write_command(&outblock, smtp_use_pipelining,
1984 "MAIL FROM:<%s>%s\r\n", return_path, buffer);
1985 mail_command = string_copy(big_buffer); /* Save for later error message */
1989 case -1: /* Transmission error */
1992 case +1: /* Block was sent */
1993 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1994 ob->command_timeout))
1996 if (errno == 0 && buffer[0] == '4')
1998 errno = ERRNO_MAIL4XX;
1999 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2001 goto RESPONSE_FAILED;
2003 pending_MAIL = FALSE;
2007 /* Pass over all the relevant recipient addresses for this host, which are the
2008 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
2009 several before we have to read the responses for those seen so far. This
2010 checking is done by a subroutine because it also needs to be done at the end.
2011 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
2012 the next one if not all are sent.
2014 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
2015 last address because we want to abort if any recipients have any kind of
2016 problem, temporary or permanent. We know that all recipient addresses will have
2017 the PENDING_DEFER status, because only one attempt is ever made, and we know
2018 that max_rcpt will be large, so all addresses will be done at once. */
2020 for (addr = first_addr;
2021 address_count < max_rcpt && addr != NULL;
2027 addr->dsn_aware = smtp_use_dsn ? dsn_support_yes : dsn_support_no;
2029 if (addr->transport_return != PENDING_DEFER) continue;
2032 no_flush = smtp_use_pipelining && (!mua_wrapper || addr->next != NULL);
2034 /* Add any DSN flags to the rcpt command and add to the sent string */
2039 if (smtp_use_dsn && (addr->dsn_flags & rf_dsnlasthop) != 1)
2041 if ((addr->dsn_flags & rf_dsnflags) != 0)
2045 Ustrcpy(p, " NOTIFY=");
2047 for (i = 0; i < 4; i++)
2048 if ((addr->dsn_flags & rf_list[i]) != 0)
2050 if (!first) *p++ = ',';
2052 Ustrcpy(p, rf_names[i]);
2057 if (addr->dsn_orcpt != NULL)
2059 string_format(p, sizeof(buffer) - (p-buffer), " ORCPT=%s",
2065 /* Now send the RCPT command, and process outstanding responses when
2066 necessary. After a timeout on RCPT, we just end the function, leaving the
2067 yield as OK, because this error can often mean that there is a problem with
2068 just one address, so we don't want to delay the host. */
2070 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s%s\r\n",
2071 transport_rcpt_address(addr, tblock->rcpt_include_affixes), igquotstr, buffer);
2073 if (count < 0) goto SEND_FAILED;
2076 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
2077 &sync_addr, host, count, ob->address_retry_include_sender,
2078 pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
2081 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2082 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2085 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2086 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2087 case 0: /* No 2xx or 5xx, but no probs */
2090 case -1: goto END_OFF; /* Timeout on RCPT */
2091 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
2093 pending_MAIL = FALSE; /* Dealt with MAIL */
2095 } /* Loop for next address */
2097 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
2098 permanently or temporarily. We should have flushed and synced after the last
2103 address_item *badaddr;
2104 for (badaddr = first_addr; badaddr; badaddr = badaddr->next)
2105 if (badaddr->transport_return != PENDING_OK)
2107 /*XXX could we find a better errno than 0 here? */
2108 set_errno(addrlist, 0, badaddr->message, FAIL,
2109 testflag(badaddr, af_pass_message), NULL);
2115 /* If ok is TRUE, we know we have got at least one good recipient, and must now
2116 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
2117 have a good recipient buffered up if we are pipelining. We don't want to waste
2118 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
2119 are pipelining. The responses are all handled by sync_responses(). */
2121 if (ok || (smtp_use_pipelining && !mua_wrapper))
2123 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
2124 if (count < 0) goto SEND_FAILED;
2125 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
2126 host, count, ob->address_retry_include_sender, pending_MAIL,
2127 ok? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
2129 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2130 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2133 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2134 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2135 case 0: break; /* No 2xx or 5xx, but no probs */
2137 case -1: goto END_OFF; /* Timeout on RCPT */
2138 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2142 /* Save the first address of the next batch. */
2146 /* If there were no good recipients (but otherwise there have been no
2147 problems), just set ok TRUE, since we have handled address-specific errors
2148 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
2149 for handling the SMTP dot-handling protocol, flagging to apply to headers as
2150 well as body. Set the appropriate timeout value to be used for each chunk.
2151 (Haven't been able to make it work using select() for writing yet.) */
2153 if (!ok) ok = TRUE; else
2155 sigalrm_seen = FALSE;
2156 transport_write_timeout = ob->data_timeout;
2157 smtp_command = US"sending data block"; /* For error messages */
2158 DEBUG(D_transport|D_v)
2159 debug_printf(" SMTP>> writing message and terminating \".\"\n");
2160 transport_count = 0;
2162 #ifndef DISABLE_DKIM
2163 ok = dkim_transport_write_message(addrlist, inblock.sock,
2164 topt_use_crlf | topt_end_dot | topt_escape_headers |
2165 (tblock->body_only? topt_no_headers : 0) |
2166 (tblock->headers_only? topt_no_body : 0) |
2167 (tblock->return_path_add? topt_add_return_path : 0) |
2168 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
2169 (tblock->envelope_to_add? topt_add_envelope_to : 0),
2170 0, /* No size limit */
2171 tblock->add_headers, tblock->remove_headers,
2172 US".", US"..", /* Escaping strings */
2173 tblock->rewrite_rules, tblock->rewrite_existflags,
2174 ob->dkim_private_key, ob->dkim_domain, ob->dkim_selector,
2175 ob->dkim_canon, ob->dkim_strict, ob->dkim_sign_headers
2178 ok = transport_write_message(addrlist, inblock.sock,
2179 topt_use_crlf | topt_end_dot | topt_escape_headers |
2180 (tblock->body_only? topt_no_headers : 0) |
2181 (tblock->headers_only? topt_no_body : 0) |
2182 (tblock->return_path_add? topt_add_return_path : 0) |
2183 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
2184 (tblock->envelope_to_add? topt_add_envelope_to : 0),
2185 0, /* No size limit */
2186 tblock->add_headers, tblock->remove_headers,
2187 US".", US"..", /* Escaping strings */
2188 tblock->rewrite_rules, tblock->rewrite_existflags);
2191 /* transport_write_message() uses write() because it is called from other
2192 places to write to non-sockets. This means that under some OS (e.g. Solaris)
2193 it can exit with "Broken pipe" as its error. This really means that the
2194 socket got closed at the far end. */
2196 transport_write_timeout = 0; /* for subsequent transports */
2198 /* Failure can either be some kind of I/O disaster (including timeout),
2199 or the failure of a transport filter or the expansion of added headers. */
2203 buffer[0] = 0; /* There hasn't been a response */
2204 goto RESPONSE_FAILED;
2207 /* We used to send the terminating "." explicitly here, but because of
2208 buffering effects at both ends of TCP/IP connections, you don't gain
2209 anything by keeping it separate, so it might as well go in the final
2210 data buffer for efficiency. This is now done by setting the topt_end_dot
2213 smtp_command = US"end of data";
2215 #ifndef DISABLE_PRDR
2216 /* For PRDR we optionally get a partial-responses warning
2217 * followed by the individual responses, before going on with
2218 * the overall response. If we don't get the warning then deal
2219 * with per non-PRDR. */
2222 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '3',
2224 if (!ok && errno == 0)
2227 case '2': prdr_active = FALSE;
2230 case '4': errno = ERRNO_DATA4XX;
2231 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2238 /* For non-PRDR SMTP, we now read a single response that applies to the
2239 whole message. If it is OK, then all the addresses have been delivered. */
2243 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2245 if (!ok && errno == 0 && buffer[0] == '4')
2247 errno = ERRNO_DATA4XX;
2248 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2252 /* For LMTP, we get back a response for every RCPT command that we sent;
2253 some may be accepted and some rejected. For those that get a response, their
2254 status is fixed; any that are accepted have been handed over, even if later
2255 responses crash - at least, that's how I read RFC 2033.
2257 If all went well, mark the recipient addresses as completed, record which
2258 host/IPaddress they were delivered to, and cut out RSET when sending another
2259 message down the same channel. Write the completed addresses to the journal
2260 now so that they are recorded in case there is a crash of hardware or
2261 software before the spool gets updated. Also record the final SMTP
2262 confirmation if needed (for SMTP only). */
2267 int delivery_time = (int)(time(NULL) - start_delivery_time);
2269 uschar *conf = NULL;
2272 /* Set up confirmation if needed - applies only to SMTP */
2275 #ifndef EXPERIMENTAL_EVENT
2276 (log_extra_selector & LX_smtp_confirmation) != 0 &&
2281 const uschar *s = string_printing(buffer);
2282 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
2283 conf = (s == buffer)? (uschar *)string_copy(s) : US s;
2286 /* Process all transported addresses - for LMTP or PRDR, read a status for
2289 for (addr = addrlist; addr != first_addr; addr = addr->next)
2291 if (addr->transport_return != PENDING_OK) continue;
2293 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
2294 remaining addresses. Otherwise, it's a return code for just the one
2295 address. For temporary errors, add a retry item for the address so that
2296 it doesn't get tried again too soon. */
2298 #ifndef DISABLE_PRDR
2299 if (lmtp || prdr_active)
2304 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2307 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
2308 addr->message = string_sprintf(
2309 #ifndef DISABLE_PRDR
2310 "%s error after %s: %s", prdr_active ? "PRDR":"LMTP",
2312 "LMTP error after %s: %s",
2314 big_buffer, string_printing(buffer));
2315 setflag(addr, af_pass_message); /* Allow message to go to user */
2316 if (buffer[0] == '5')
2317 addr->transport_return = FAIL;
2320 errno = ERRNO_DATA4XX;
2321 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2322 addr->transport_return = DEFER;
2323 #ifndef DISABLE_PRDR
2326 retry_add_item(addr, addr->address_retry_key, 0);
2330 completed_address = TRUE; /* NOW we can set this flag */
2331 if ((log_extra_selector & LX_smtp_confirmation) != 0)
2333 const uschar *s = string_printing(buffer);
2334 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
2335 conf = (s == buffer)? (uschar *)string_copy(s) : US s;
2339 /* SMTP, or success return from LMTP for this address. Pass back the
2340 actual host that was used. */
2342 addr->transport_return = OK;
2343 addr->more_errno = delivery_time;
2344 addr->host_used = host;
2345 addr->special_action = flag;
2346 addr->message = conf;
2347 #ifndef DISABLE_PRDR
2348 if (prdr_active) addr->flags |= af_prdr_used;
2352 #ifndef DISABLE_PRDR
2356 /* Update the journal. For homonymic addresses, use the base address plus
2357 the transport name. See lots of comments in deliver.c about the reasons
2358 for the complications when homonyms are involved. Just carry on after
2359 write error, as it may prove possible to update the spool file later. */
2361 if (testflag(addr, af_homonym))
2362 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2364 sprintf(CS buffer, "%.500s\n", addr->unique);
2366 DEBUG(D_deliver) debug_printf("journalling %s", buffer);
2367 len = Ustrlen(CS buffer);
2368 if (write(journal_fd, buffer, len) != len)
2369 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2370 "%s: %s", buffer, strerror(errno));
2374 #ifndef DISABLE_PRDR
2377 /* PRDR - get the final, overall response. For any non-success
2378 upgrade all the address statuses. */
2379 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2383 if(errno == 0 && buffer[0] == '4')
2385 errno = ERRNO_DATA4XX;
2386 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2388 for (addr = addrlist; addr != first_addr; addr = addr->next)
2389 if (buffer[0] == '5' || addr->transport_return == OK)
2390 addr->transport_return = PENDING_OK; /* allow set_errno action */
2391 goto RESPONSE_FAILED;
2394 /* Update the journal, or setup retry. */
2395 for (addr = addrlist; addr != first_addr; addr = addr->next)
2396 if (addr->transport_return == OK)
2398 if (testflag(addr, af_homonym))
2399 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2401 sprintf(CS buffer, "%.500s\n", addr->unique);
2403 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s", buffer);
2404 len = Ustrlen(CS buffer);
2405 if (write(journal_fd, buffer, len) != len)
2406 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2407 "%s: %s", buffer, strerror(errno));
2409 else if (addr->transport_return == DEFER)
2410 retry_add_item(addr, addr->address_retry_key, -2);
2414 /* Ensure the journal file is pushed out to disk. */
2416 if (EXIMfsync(journal_fd) < 0)
2417 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
2423 /* Handle general (not specific to one address) failures here. The value of ok
2424 is used to skip over this code on the falling through case. A timeout causes a
2425 deferral. Other errors may defer or fail according to the response code, and
2426 may set up a special errno value, e.g. after connection chopped, which is
2427 assumed if errno == 0 and there is no text in the buffer. If control reaches
2428 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
2429 the problem is not related to this specific message. */
2438 send_quit = check_response(host, &save_errno, addrlist->more_errno,
2439 buffer, &code, &message, &pass_message);
2445 message = US string_sprintf("send() to %s [%s] failed: %s",
2446 host->name, host->address, strerror(save_errno));
2450 /* This label is jumped to directly when a TLS negotiation has failed,
2451 or was not done for a host for which it is required. Values will be set
2452 in message and save_errno, and setting_up will always be true. Treat as
2453 a temporary error. */
2460 /* If the failure happened while setting up the call, see if the failure was
2461 a 5xx response (this will either be on connection, or following HELO - a 5xx
2462 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
2463 never going to accept them. For other errors during setting up (timeouts or
2464 whatever), defer all addresses, and yield DEFER, so that the host is not
2465 tried again for a while. */
2468 ok = FALSE; /* For when reached by GOTO */
2473 set_errno(addrlist, save_errno, message, FAIL, pass_message, host);
2476 set_errno(addrlist, save_errno, message, DEFER, pass_message, host);
2481 /* We want to handle timeouts after MAIL or "." and loss of connection after
2482 "." specially. They can indicate a problem with the sender address or with
2483 the contents of the message rather than a real error on the connection. These
2484 cases are treated in the same way as a 4xx response. This next bit of code
2485 does the classification. */
2496 message_error = TRUE;
2500 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
2501 Ustrncmp(smtp_command,"end ",4) == 0;
2504 case ERRNO_SMTPCLOSED:
2505 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
2509 message_error = FALSE;
2513 /* Handle the cases that are treated as message errors. These are:
2515 (a) negative response or timeout after MAIL
2516 (b) negative response after DATA
2517 (c) negative response or timeout or dropped connection after "."
2519 It won't be a negative response or timeout after RCPT, as that is dealt
2520 with separately above. The action in all cases is to set an appropriate
2521 error code for all the addresses, but to leave yield set to OK because the
2522 host itself has not failed. Of course, it might in practice have failed
2523 when we've had a timeout, but if so, we'll discover that at the next
2524 delivery attempt. For a temporary error, set the message_defer flag, and
2525 write to the logs for information if this is not the last host. The error
2526 for the last host will be logged as part of the address's log line. */
2530 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
2531 set_errno(addrlist, save_errno, message, (code == '5')? FAIL : DEFER,
2532 pass_message, host);
2534 /* If there's an errno, the message contains just the identity of
2537 if (code != '5') /* Anything other than 5 is treated as temporary */
2540 message = US string_sprintf("%s: %s", message, strerror(save_errno));
2541 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
2542 msglog_line(host, message);
2543 *message_defer = TRUE;
2547 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
2548 ".", or some other transportation error. We defer all addresses and yield
2549 DEFER, except for the case of failed add_headers expansion, or a transport
2550 filter failure, when the yield should be ERROR, to stop it trying other
2555 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
2556 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
2557 set_errno(addrlist, save_errno, message, DEFER, pass_message, host);
2563 /* If all has gone well, send_quit will be set TRUE, implying we can end the
2564 SMTP session tidily. However, if there were too many addresses to send in one
2565 message (indicated by first_addr being non-NULL) we want to carry on with the
2566 rest of them. Also, it is desirable to send more than one message down the SMTP
2567 connection if there are several waiting, provided we haven't already sent so
2568 many as to hit the configured limit. The function transport_check_waiting looks
2569 for a waiting message and returns its id. Then transport_pass_socket tries to
2570 set up a continued delivery by passing the socket on to another process. The
2571 variable send_rset is FALSE if a message has just been successfully transfered.
2573 If we are already sending down a continued channel, there may be further
2574 addresses not yet delivered that are aimed at the same host, but which have not
2575 been passed in this run of the transport. In this case, continue_more will be
2576 true, and all we should do is send RSET if necessary, and return, leaving the
2579 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
2580 do not want to continue with other messages down the same channel, because that
2581 can lead to looping between two or more messages, all with the same,
2582 temporarily failing address(es). [The retry information isn't updated yet, so
2583 new processes keep on trying.] We probably also don't want to try more of this
2584 message's addresses either.
2586 If we have started a TLS session, we have to end it before passing the
2587 connection to a new process. However, not all servers can handle this (Exim
2588 can), so we do not pass such a connection on if the host matches
2589 hosts_nopass_tls. */
2592 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
2593 "yield=%d first_address is %sNULL\n", ok, send_quit, send_rset,
2594 continue_more, yield, (first_addr == NULL)? "":"not ");
2596 if (completed_address && ok && send_quit)
2599 smtp_compare_t t_compare;
2601 t_compare.tblock = tblock;
2602 t_compare.current_sender_address = sender_address;
2604 if ( first_addr != NULL
2606 || ( ( tls_out.active < 0
2607 || verify_check_given_host(&ob->hosts_nopass_tls, host) != OK
2610 transport_check_waiting(tblock->name, host->name,
2611 tblock->connection_max_messages, new_message_id, &more,
2612 (oicf)smtp_are_same_identities, (void*)&t_compare)
2620 if (! (ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
2622 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
2623 host->address, strerror(save_errno));
2626 else if (! (ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2627 ob->command_timeout)))
2630 send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
2634 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
2635 host->name, host->address, msg);
2640 /* Either RSET was not needed, or it succeeded */
2644 if (first_addr != NULL) /* More addresses still to be sent */
2645 { /* in this run of the transport */
2646 continue_sequence++; /* Causes * in logging */
2649 if (continue_more) return yield; /* More addresses for another run */
2651 /* Pass the socket to a new Exim process. Before doing so, we must shut
2652 down TLS. Not all MTAs allow for the continuation of the SMTP session
2653 when TLS is shut down. We test for this by sending a new EHLO. If we
2654 don't get a good response, we don't attempt to pass the socket on. */
2657 if (tls_out.active >= 0)
2659 tls_close(FALSE, TRUE);
2663 ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
2664 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2665 ob->command_timeout);
2669 /* If the socket is successfully passed, we musn't send QUIT (or
2670 indeed anything!) from here. */
2672 if (ok && transport_pass_socket(tblock->name, host->name, host->address,
2673 new_message_id, inblock.sock))
2679 /* If RSET failed and there are addresses left, they get deferred. */
2681 else set_errno(first_addr, errno, msg, DEFER, FALSE, host);
2685 /* End off tidily with QUIT unless the connection has died or the socket has
2686 been passed to another process. There has been discussion on the net about what
2687 to do after sending QUIT. The wording of the RFC suggests that it is necessary
2688 to wait for a response, but on the other hand, there isn't anything one can do
2689 with an error response, other than log it. Exim used to do that. However,
2690 further discussion suggested that it is positively advantageous not to wait for
2691 the response, but to close the session immediately. This is supposed to move
2692 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
2693 load from the server. (Hosts that are both servers and clients may not see much
2694 difference, of course.) Further discussion indicated that this was safe to do
2695 on Unix systems which have decent implementations of TCP/IP that leave the
2696 connection around for a while (TIME_WAIT) after the application has gone away.
2697 This enables the response sent by the server to be properly ACKed rather than
2698 timed out, as can happen on broken TCP/IP implementations on other OS.
2700 This change is being made on 31-Jul-98. After over a year of trouble-free
2701 operation, the old commented-out code was removed on 17-Sep-99. */
2704 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2709 tls_close(FALSE, TRUE);
2712 /* Close the socket, and return the appropriate value, first setting
2713 works because the NULL setting is passed back to the calling process, and
2714 remote_max_parallel is forced to 1 when delivering over an existing connection,
2716 If all went well and continue_more is set, we shouldn't actually get here if
2717 there are further addresses, as the return above will be taken. However,
2718 writing RSET might have failed, or there may be other addresses whose hosts are
2719 specified in the transports, and therefore not visible at top level, in which
2720 case continue_more won't get set. */
2722 (void)close(inblock.sock);
2724 #ifdef EXPERIMENTAL_EVENT
2725 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
2728 continue_transport = NULL;
2729 continue_hostname = NULL;
2736 /*************************************************
2737 * Closedown entry point *
2738 *************************************************/
2740 /* This function is called when exim is passed an open smtp channel
2741 from another incarnation, but the message which it has been asked
2742 to deliver no longer exists. The channel is on stdin.
2744 We might do fancy things like looking for another message to send down
2745 the channel, but if the one we sought has gone, it has probably been
2746 delivered by some other process that itself will seek further messages,
2747 so just close down our connection.
2749 Argument: pointer to the transport instance block
2754 smtp_transport_closedown(transport_instance *tblock)
2756 smtp_transport_options_block *ob =
2757 (smtp_transport_options_block *)(tblock->options_block);
2758 smtp_inblock inblock;
2759 smtp_outblock outblock;
2761 uschar inbuffer[4096];
2762 uschar outbuffer[16];
2764 inblock.sock = fileno(stdin);
2765 inblock.buffer = inbuffer;
2766 inblock.buffersize = sizeof(inbuffer);
2767 inblock.ptr = inbuffer;
2768 inblock.ptrend = inbuffer;
2770 outblock.sock = inblock.sock;
2771 outblock.buffersize = sizeof(outbuffer);
2772 outblock.buffer = outbuffer;
2773 outblock.ptr = outbuffer;
2774 outblock.cmd_count = 0;
2775 outblock.authenticating = FALSE;
2777 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2778 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2779 ob->command_timeout);
2780 (void)close(inblock.sock);
2785 /*************************************************
2786 * Prepare addresses for delivery *
2787 *************************************************/
2789 /* This function is called to flush out error settings from previous delivery
2790 attempts to other hosts. It also records whether we got here via an MX record
2791 or not in the more_errno field of the address. We are interested only in
2792 addresses that are still marked DEFER - others may have got delivered to a
2793 previously considered IP address. Set their status to PENDING_DEFER to indicate
2794 which ones are relevant this time.
2797 addrlist the list of addresses
2798 host the host we are delivering to
2800 Returns: the first address for this delivery
2803 static address_item *
2804 prepare_addresses(address_item *addrlist, host_item *host)
2806 address_item *first_addr = NULL;
2808 for (addr = addrlist; addr != NULL; addr = addr->next)
2809 if (addr->transport_return == DEFER)
2811 if (first_addr == NULL) first_addr = addr;
2812 addr->transport_return = PENDING_DEFER;
2813 addr->basic_errno = 0;
2814 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
2815 addr->message = NULL;
2817 addr->cipher = NULL;
2818 addr->ourcert = NULL;
2819 addr->peercert = NULL;
2820 addr->peerdn = NULL;
2821 addr->ocsp = OCSP_NOT_REQ;
2829 /*************************************************
2830 * Main entry point *
2831 *************************************************/
2833 /* See local README for interface details. As this is a remote transport, it is
2834 given a chain of addresses to be delivered in one connection, if possible. It
2835 always returns TRUE, indicating that each address has its own independent
2836 status set, except if there is a setting up problem, in which case it returns
2840 smtp_transport_entry(
2841 transport_instance *tblock, /* data for this instantiation */
2842 address_item *addrlist) /* addresses we are working on */
2846 int hosts_defer = 0;
2848 int hosts_looked_up = 0;
2849 int hosts_retry = 0;
2850 int hosts_serial = 0;
2851 int hosts_total = 0;
2852 int total_hosts_tried = 0;
2854 BOOL expired = TRUE;
2855 BOOL continuing = continue_hostname != NULL;
2856 uschar *expanded_hosts = NULL;
2858 uschar *tid = string_sprintf("%s transport", tblock->name);
2859 smtp_transport_options_block *ob =
2860 (smtp_transport_options_block *)(tblock->options_block);
2861 host_item *hostlist = addrlist->host_list;
2862 host_item *host = NULL;
2866 debug_printf("%s transport entered\n", tblock->name);
2867 for (addr = addrlist; addr != NULL; addr = addr->next)
2868 debug_printf(" %s\n", addr->address);
2869 if (continuing) debug_printf("already connected to %s [%s]\n",
2870 continue_hostname, continue_host_address);
2873 /* Set the flag requesting that these hosts be added to the waiting
2874 database if the delivery fails temporarily or if we are running with
2875 queue_smtp or a 2-stage queue run. This gets unset for certain
2876 kinds of error, typically those that are specific to the message. */
2878 update_waiting = TRUE;
2880 /* If a host list is not defined for the addresses - they must all have the
2881 same one in order to be passed to a single transport - or if the transport has
2882 a host list with hosts_override set, use the host list supplied with the
2883 transport. It is an error for this not to exist. */
2885 if (hostlist == NULL || (ob->hosts_override && ob->hosts != NULL))
2887 if (ob->hosts == NULL)
2889 addrlist->message = string_sprintf("%s transport called with no hosts set",
2891 addrlist->transport_return = PANIC;
2892 return FALSE; /* Only top address has status */
2895 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
2898 /* If the transport's host list contains no '$' characters, and we are not
2899 randomizing, it is fixed and therefore a chain of hosts can be built once
2900 and for all, and remembered for subsequent use by other calls to this
2901 transport. If, on the other hand, the host list does contain '$', or we are
2902 randomizing its order, we have to rebuild it each time. In the fixed case,
2903 as the hosts string will never be used again, it doesn't matter that we
2904 replace all the : characters with zeros. */
2906 if (ob->hostlist == NULL)
2908 uschar *s = ob->hosts;
2910 if (Ustrchr(s, '$') != NULL)
2912 if (!(expanded_hosts = expand_string(s)))
2914 addrlist->message = string_sprintf("failed to expand list of hosts "
2915 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
2916 addrlist->transport_return = search_find_defer? DEFER : PANIC;
2917 return FALSE; /* Only top address has status */
2919 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
2920 "\"%s\"\n", s, expanded_hosts);
2924 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
2926 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
2928 /* Check that the expansion yielded something useful. */
2929 if (hostlist == NULL)
2932 string_sprintf("%s transport has empty hosts setting", tblock->name);
2933 addrlist->transport_return = PANIC;
2934 return FALSE; /* Only top address has status */
2937 /* If there was no expansion of hosts, save the host list for
2940 if (!expanded_hosts) ob->hostlist = hostlist;
2943 /* This is not the first time this transport has been run in this delivery;
2944 the host list was built previously. */
2947 hostlist = ob->hostlist;
2950 /* The host list was supplied with the address. If hosts_randomize is set, we
2951 must sort it into a random order if it did not come from MX records and has not
2952 already been randomized (but don't bother if continuing down an existing
2955 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continuing)
2957 host_item *newlist = NULL;
2958 while (hostlist != NULL)
2960 host_item *h = hostlist;
2961 hostlist = hostlist->next;
2963 h->sort_key = random_number(100);
2965 if (newlist == NULL)
2970 else if (h->sort_key < newlist->sort_key)
2977 host_item *hh = newlist;
2978 while (hh->next != NULL)
2980 if (h->sort_key < hh->next->sort_key) break;
2988 hostlist = addrlist->host_list = newlist;
2991 /* Sort out the default port. */
2993 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
2995 /* For each host-plus-IP-address on the list:
2997 . If this is a continued delivery and the host isn't the one with the
2998 current connection, skip.
3000 . If the status is unusable (i.e. previously failed or retry checked), skip.
3002 . If no IP address set, get the address, either by turning the name into
3003 an address, calling gethostbyname if gethostbyname is on, or by calling
3004 the DNS. The DNS may yield multiple addresses, in which case insert the
3005 extra ones into the list.
3007 . Get the retry data if not previously obtained for this address and set the
3008 field which remembers the state of this address. Skip if the retry time is
3009 not reached. If not, remember whether retry data was found. The retry string
3010 contains both the name and the IP address.
3012 . Scan the list of addresses and mark those whose status is DEFER as
3013 PENDING_DEFER. These are the only ones that will be processed in this cycle
3016 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
3017 Some addresses may be successfully delivered, others may fail, and yet
3018 others may get temporary errors and so get marked DEFER.
3020 . The return from the delivery attempt is OK if a connection was made and a
3021 valid SMTP dialogue was completed. Otherwise it is DEFER.
3023 . If OK, add a "remove" retry item for this host/IPaddress, if any.
3025 . If fail to connect, or other defer state, add a retry item.
3027 . If there are any addresses whose status is still DEFER, carry on to the
3028 next host/IPaddress, unless we have tried the number of hosts given
3029 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
3030 there is some fancy logic for hosts_max_try that means its limit can be
3031 overstepped in some circumstances.
3033 If we get to the end of the list, all hosts have deferred at least one address,
3034 or not reached their retry times. If delay_after_cutoff is unset, it requests a
3035 delivery attempt to those hosts whose last try was before the arrival time of
3036 the current message. To cope with this, we have to go round the loop a second
3037 time. After that, set the status and error data for any addresses that haven't
3038 had it set already. */
3040 for (cutoff_retry = 0; expired &&
3041 cutoff_retry < ((ob->delay_after_cutoff)? 1 : 2);
3044 host_item *nexthost = NULL;
3045 int unexpired_hosts_tried = 0;
3047 for (host = hostlist;
3049 unexpired_hosts_tried < ob->hosts_max_try &&
3050 total_hosts_tried < ob->hosts_max_try_hardlimit;
3056 BOOL serialized = FALSE;
3057 BOOL host_is_expired = FALSE;
3058 BOOL message_defer = FALSE;
3059 BOOL ifchanges = FALSE;
3060 BOOL some_deferred = FALSE;
3061 address_item *first_addr = NULL;
3062 uschar *interface = NULL;
3063 uschar *retry_host_key = NULL;
3064 uschar *retry_message_key = NULL;
3065 uschar *serialize_key = NULL;
3067 /* Default next host is next host. :-) But this can vary if the
3068 hosts_max_try limit is hit (see below). It may also be reset if a host
3069 address is looked up here (in case the host was multihomed). */
3071 nexthost = host->next;
3073 /* If the address hasn't yet been obtained from the host name, look it up
3074 now, unless the host is already marked as unusable. If it is marked as
3075 unusable, it means that the router was unable to find its IP address (in
3076 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
3077 the lookup failed last time. We don't get this far if *all* MX records
3078 point to non-existent hosts; that is treated as a hard error.
3080 We can just skip this host entirely. When the hosts came from the router,
3081 the address will timeout based on the other host(s); when the address is
3082 looked up below, there is an explicit retry record added.
3084 Note that we mustn't skip unusable hosts if the address is not unset; they
3085 may be needed as expired hosts on the 2nd time round the cutoff loop. */
3087 if (host->address == NULL)
3089 int new_port, flags;
3092 if (host->status >= hstatus_unusable)
3094 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
3099 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
3101 /* The host name is permitted to have an attached port. Find it, and
3102 strip it from the name. Just remember it for now. */
3104 new_port = host_item_get_port(host);
3106 /* Count hosts looked up */
3110 /* Find by name if so configured, or if it's an IP address. We don't
3111 just copy the IP address, because we need the test-for-local to happen. */
3113 flags = HOST_FIND_BY_A;
3114 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
3115 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
3117 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
3118 rc = host_find_byname(host, NULL, flags, NULL, TRUE);
3120 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
3121 ob->dnssec_request_domains, ob->dnssec_require_domains,
3124 /* Update the host (and any additional blocks, resulting from
3125 multihoming) with a host-specific port, if any. */
3127 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
3129 /* Failure to find the host at this time (usually DNS temporary failure)
3130 is really a kind of routing failure rather than a transport failure.
3131 Therefore we add a retry item of the routing kind, not to stop us trying
3132 to look this name up here again, but to ensure the address gets timed
3133 out if the failures go on long enough. A complete failure at this point
3134 commonly points to a configuration error, but the best action is still
3135 to carry on for the next host. */
3137 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
3139 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
3141 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
3142 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
3143 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
3144 host->status = hstatus_unusable;
3146 for (addr = addrlist; addr != NULL; addr = addr->next)
3148 if (addr->transport_return != DEFER) continue;
3149 addr->basic_errno = ERRNO_UNKNOWNHOST;
3151 string_sprintf("failed to lookup IP address for %s", host->name);
3156 /* If the host is actually the local host, we may have a problem, or
3157 there may be some cunning configuration going on. In the problem case,
3158 log things and give up. The default transport status is already DEFER. */
3160 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
3162 for (addr = addrlist; addr != NULL; addr = addr->next)
3164 addr->basic_errno = 0;
3165 addr->message = string_sprintf("%s transport found host %s to be "
3166 "local", tblock->name, host->name);
3170 } /* End of block for IP address lookup */
3172 /* If this is a continued delivery, we are interested only in the host
3173 which matches the name of the existing open channel. The check is put
3174 here after the local host lookup, in case the name gets expanded as a
3175 result of the lookup. Set expired FALSE, to save the outer loop executing
3178 if (continuing && (Ustrcmp(continue_hostname, host->name) != 0 ||
3179 Ustrcmp(continue_host_address, host->address) != 0))
3182 continue; /* With next host */
3185 /* Reset the default next host in case a multihomed host whose addresses
3186 are not looked up till just above added to the host list. */
3188 nexthost = host->next;
3190 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
3191 domain is in queue_smtp_domains, we don't actually want to attempt any
3192 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
3193 there is a lookup defer in queue_smtp_domains, proceed as if the domain
3194 were not in it. We don't want to hold up all SMTP deliveries! Except when
3195 doing a two-stage queue run, don't do this if forcing. */
3197 if ((!deliver_force || queue_2stage) && (queue_smtp ||
3198 match_isinlist(addrlist->domain,
3199 (const uschar **)&queue_smtp_domains, 0,
3200 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
3203 for (addr = addrlist; addr != NULL; addr = addr->next)
3205 if (addr->transport_return != DEFER) continue;
3206 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
3208 continue; /* With next host */
3211 /* Count hosts being considered - purely for an intelligent comment
3212 if none are usable. */
3216 /* Set $host and $host address now in case they are needed for the
3217 interface expansion or the serialize_hosts check; they remain set if an
3218 actual delivery happens. */
3220 deliver_host = host->name;
3221 deliver_host_address = host->address;
3222 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
3223 : host->dnssec == DS_NO ? US"no"
3226 /* Set up a string for adding to the retry key if the port number is not
3227 the standard SMTP port. A host may have its own port setting that overrides
3230 pistring = string_sprintf(":%d", (host->port == PORT_NONE)?
3232 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
3234 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
3235 string changes upon expansion, we must add it to the key that is used for
3236 retries, because connections to the same host from a different interface
3237 should be treated separately. */
3239 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET : AF_INET6;
3240 if (!smtp_get_interface(ob->interface, host_af, addrlist, &ifchanges,
3243 if (ifchanges) pistring = string_sprintf("%s/%s", pistring, interface);
3245 /* The first time round the outer loop, check the status of the host by
3246 inspecting the retry data. The second time round, we are interested only
3247 in expired hosts that haven't been tried since this message arrived. */
3249 if (cutoff_retry == 0)
3252 /* Ensure the status of the address is set by checking retry data if
3253 necessary. There may be host-specific retry data (applicable to all
3254 messages) and also data for retries of a specific message at this host.
3255 If either of these retry records are actually read, the keys used are
3256 returned to save recomputing them later. */
3258 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3259 US"retry_include_ip_address", ob->retry_include_ip_address,
3260 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3261 continue; /* with next host */
3263 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
3264 incl_ip, &retry_host_key, &retry_message_key);
3266 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
3267 (host->address == NULL)? US"" : host->address, pistring,
3268 (host->status == hstatus_usable)? "usable" :
3269 (host->status == hstatus_unusable)? "unusable" :
3270 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
3272 /* Skip this address if not usable at this time, noting if it wasn't
3273 actually expired, both locally and in the address. */
3275 switch (host->status)
3277 case hstatus_unusable:
3279 setflag(addrlist, af_retry_skipped);
3282 case hstatus_unusable_expired:
3285 case hwhy_retry: hosts_retry++; break;
3286 case hwhy_failed: hosts_fail++; break;
3287 case hwhy_deferred: hosts_defer++; break;
3290 /* If there was a retry message key, implying that previously there
3291 was a message-specific defer, we don't want to update the list of
3292 messages waiting for these hosts. */
3294 if (retry_message_key != NULL) update_waiting = FALSE;
3295 continue; /* With the next host or IP address */
3299 /* Second time round the loop: if the address is set but expired, and
3300 the message is newer than the last try, let it through. */
3304 if (host->address == NULL ||
3305 host->status != hstatus_unusable_expired ||
3306 host->last_try > received_time)
3309 debug_printf("trying expired host %s [%s]%s\n",
3310 host->name, host->address, pistring);
3311 host_is_expired = TRUE;
3314 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
3315 it remains TRUE only if all hosts are expired and none are actually tried.
3320 /* If this host is listed as one to which access must be serialized,
3321 see if another Exim process has a connection to it, and if so, skip
3322 this host. If not, update the database to record our connection to it
3323 and remember this for later deletion. Do not do any of this if we are
3324 sending the message down a pre-existing connection. */
3327 verify_check_given_host(&ob->serialize_hosts, host) == OK)
3329 serialize_key = string_sprintf("host-serialize-%s", host->name);
3330 if (!enq_start(serialize_key))
3333 debug_printf("skipping host %s because another Exim process "
3334 "is connected to it\n", host->name);
3341 /* OK, we have an IP address that is not waiting for its retry time to
3342 arrive (it might be expired) OR (second time round the loop) we have an
3343 expired host that hasn't been tried since the message arrived. Have a go
3344 at delivering the message to it. First prepare the addresses by flushing
3345 out the result of previous attempts, and finding the first address that
3346 is still to be delivered. */
3348 first_addr = prepare_addresses(addrlist, host);
3350 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
3351 message_id, host->name, host->address, addrlist->address,
3352 (addrlist->next == NULL)? "" : ", ...");
3354 set_process_info("delivering %s to %s [%s] (%s%s)",
3355 message_id, host->name, host->address, addrlist->address,
3356 (addrlist->next == NULL)? "" : ", ...");
3358 /* This is not for real; don't do the delivery. If there are
3359 any remaining hosts, list them. */
3364 set_errno(addrlist, 0, NULL, OK, FALSE, NULL);
3365 for (addr = addrlist; addr != NULL; addr = addr->next)
3367 addr->host_used = host;
3368 addr->special_action = '*';
3369 addr->message = US"delivery bypassed by -N option";
3373 debug_printf("*** delivery by %s transport bypassed by -N option\n"
3374 "*** host and remaining hosts:\n", tblock->name);
3375 for (host2 = host; host2 != NULL; host2 = host2->next)
3376 debug_printf(" %s [%s]\n", host2->name,
3377 (host2->address == NULL)? US"unset" : host2->address);
3382 /* This is for real. If the host is expired, we don't count it for
3383 hosts_max_retry. This ensures that all hosts must expire before an address
3384 is timed out, unless hosts_max_try_hardlimit (which protects against
3385 lunatic DNS configurations) is reached.
3387 If the host is not expired and we are about to hit the hosts_max_retry
3388 limit, check to see if there is a subsequent hosts with a different MX
3389 value. If so, make that the next host, and don't count this one. This is a
3390 heuristic to make sure that different MXs do get tried. With a normal kind
3391 of retry rule, they would get tried anyway when the earlier hosts were
3392 delayed, but if the domain has a "retry every time" type of rule - as is
3393 often used for the the very large ISPs, that won't happen. */
3398 /* Make a copy of the host if it is local to this invocation
3399 of the transport. */
3403 thost = store_get(sizeof(host_item));
3405 thost->name = string_copy(host->name);
3406 thost->address = string_copy(host->address);
3411 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
3415 debug_printf("hosts_max_try limit reached with this host\n");
3416 for (h = host; h != NULL; h = h->next)
3417 if (h->mx != host->mx) break;
3421 unexpired_hosts_tried--;
3422 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
3423 "and will be tried\n");
3427 /* Attempt the delivery. */
3429 total_hosts_tried++;
3430 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
3431 &message_defer, FALSE);
3434 OK => connection made, each address contains its result;
3435 message_defer is set for message-specific defers (when all
3436 recipients are marked defer)
3437 DEFER => there was a non-message-specific delivery problem;
3438 ERROR => there was a problem setting up the arguments for a filter,
3439 or there was a problem with expanding added headers
3442 /* If the result is not OK, there was a non-message-specific problem.
3443 If the result is DEFER, we need to write to the logs saying what happened
3444 for this particular host, except in the case of authentication and TLS
3445 failures, where the log has already been written. If all hosts defer a
3446 general message is written at the end. */
3448 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL &&
3449 first_addr->basic_errno != ERRNO_TLSFAILURE)
3450 write_logs(first_addr, host);
3452 #ifdef EXPERIMENTAL_EVENT
3454 deferred_event_raise(first_addr, host);
3457 /* If STARTTLS was accepted, but there was a failure in setting up the
3458 TLS session (usually a certificate screwup), and the host is not in
3459 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
3460 TLS forcibly turned off. We have to start from scratch with a new SMTP
3461 connection. That's why the retry is done from here, not from within
3462 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
3463 session, so the in-clear transmission after those errors, if permitted,
3464 happens inside smtp_deliver().] */
3468 && first_addr->basic_errno == ERRNO_TLSFAILURE
3469 && ob->tls_tempfail_tryclear
3470 && verify_check_given_host(&ob->hosts_require_tls, host) != OK
3473 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
3474 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
3475 first_addr = prepare_addresses(addrlist, host);
3476 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
3477 &message_defer, TRUE);
3478 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
3479 write_logs(first_addr, host);
3480 # ifdef EXPERIMENTAL_EVENT
3482 deferred_event_raise(first_addr, host);
3485 #endif /*SUPPORT_TLS*/
3488 /* Delivery attempt finished */
3490 rs = (rc == OK)? US"OK" : (rc == DEFER)? US"DEFER" : (rc == ERROR)?
3493 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
3494 message_id, host->name, host->address, addrlist->address,
3495 (addrlist->next == NULL)? "" : " (& others)", rs);
3497 /* Release serialization if set up */
3499 if (serialized) enq_end(serialize_key);
3501 /* If the result is DEFER, or if a host retry record is known to exist, we
3502 need to add an item to the retry chain for updating the retry database
3503 at the end of delivery. We only need to add the item to the top address,
3504 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
3505 for any other delivery attempts using the same address. (It is copied into
3506 the unusable tree at the outer level, so even if different address blocks
3507 contain the same address, it still won't get tried again.) */
3509 if (rc == DEFER || retry_host_key != NULL)
3511 int delete_flag = (rc != DEFER)? rf_delete : 0;
3512 if (retry_host_key == NULL)
3515 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3516 US"retry_include_ip_address", ob->retry_include_ip_address,
3517 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3518 incl_ip = TRUE; /* error; use most-specific retry record */
3520 retry_host_key = incl_ip ?
3521 string_sprintf("T:%S:%s%s", host->name, host->address, pistring) :
3522 string_sprintf("T:%S%s", host->name, pistring);
3525 /* If a delivery of another message over an existing SMTP connection
3526 yields DEFER, we do NOT set up retry data for the host. This covers the
3527 case when there are delays in routing the addresses in the second message
3528 that are so long that the server times out. This is alleviated by not
3529 routing addresses that previously had routing defers when handling an
3530 existing connection, but even so, this case may occur (e.g. if a
3531 previously happily routed address starts giving routing defers). If the
3532 host is genuinely down, another non-continued message delivery will
3533 notice it soon enough. */
3535 if (delete_flag != 0 || !continuing)
3536 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
3538 /* We may have tried an expired host, if its retry time has come; ensure
3539 the status reflects the expiry for the benefit of any other addresses. */
3543 host->status = (host_is_expired)?
3544 hstatus_unusable_expired : hstatus_unusable;
3545 host->why = hwhy_deferred;
3549 /* If message_defer is set (host was OK, but every recipient got deferred
3550 because of some message-specific problem), or if that had happened
3551 previously so that a message retry key exists, add an appropriate item
3552 to the retry chain. Note that if there was a message defer but now there is
3553 a host defer, the message defer record gets deleted. That seems perfectly
3554 reasonable. Also, stop the message from being remembered as waiting
3555 for specific hosts. */
3557 if (message_defer || retry_message_key != NULL)
3559 int delete_flag = message_defer? 0 : rf_delete;
3560 if (retry_message_key == NULL)
3563 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3564 US"retry_include_ip_address", ob->retry_include_ip_address,
3565 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3566 incl_ip = TRUE; /* error; use most-specific retry record */
3568 retry_message_key = incl_ip ?
3569 string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
3571 string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
3573 retry_add_item(addrlist, retry_message_key,
3574 rf_message | rf_host | delete_flag);
3575 update_waiting = FALSE;
3578 /* Any return other than DEFER (that is, OK or ERROR) means that the
3579 addresses have got their final statuses filled in for this host. In the OK
3580 case, see if any of them are deferred. */
3584 for (addr = addrlist; addr != NULL; addr = addr->next)
3586 if (addr->transport_return == DEFER)
3588 some_deferred = TRUE;
3594 /* If no addresses deferred or the result was ERROR, return. We do this for
3595 ERROR because a failing filter set-up or add_headers expansion is likely to
3596 fail for any host we try. */
3598 if (rc == ERROR || (rc == OK && !some_deferred))
3600 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3601 return TRUE; /* Each address has its status */
3604 /* If the result was DEFER or some individual addresses deferred, let
3605 the loop run to try other hosts with the deferred addresses, except for the
3606 case when we were trying to deliver down an existing channel and failed.
3607 Don't try any other hosts in this case. */
3609 if (continuing) break;
3611 /* If the whole delivery, or some individual addresses, were deferred and
3612 there are more hosts that could be tried, do not count this host towards
3613 the hosts_max_try limit if the age of the message is greater than the
3614 maximum retry time for this host. This means we may try try all hosts,
3615 ignoring the limit, when messages have been around for some time. This is
3616 important because if we don't try all hosts, the address will never time
3617 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
3619 if ((rc == DEFER || some_deferred) && nexthost != NULL)
3622 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
3624 if (retry != NULL && retry->rules != NULL)
3626 retry_rule *last_rule;
3627 for (last_rule = retry->rules;
3628 last_rule->next != NULL;
3629 last_rule = last_rule->next);
3630 timedout = time(NULL) - received_time > last_rule->timeout;
3632 else timedout = TRUE; /* No rule => timed out */
3636 unexpired_hosts_tried--;
3637 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
3638 "hosts_max_try (message older than host's retry time)\n");
3641 } /* End of loop for trying multiple hosts. */
3643 /* This is the end of the loop that repeats iff expired is TRUE and
3644 ob->delay_after_cutoff is FALSE. The second time round we will
3645 try those hosts that haven't been tried since the message arrived. */
3649 debug_printf("all IP addresses skipped or deferred at least one address\n");
3650 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
3651 debug_printf("retrying IP addresses not tried since message arrived\n");
3656 /* Get here if all IP addresses are skipped or defer at least one address. In
3657 MUA wrapper mode, this will happen only for connection or other non-message-
3658 specific failures. Force the delivery status for all addresses to FAIL. */
3662 for (addr = addrlist; addr != NULL; addr = addr->next)
3663 addr->transport_return = FAIL;
3667 /* In the normal, non-wrapper case, add a standard message to each deferred
3668 address if there hasn't been an error, that is, if it hasn't actually been
3669 tried this time. The variable "expired" will be FALSE if any deliveries were
3670 actually tried, or if there was at least one host that was not expired. That
3671 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
3672 a delivery has been tried, an error code will be set, and the failing of the
3673 message is handled by the retry code later.
3675 If queue_smtp is set, or this transport was called to send a subsequent message
3676 down an existing TCP/IP connection, and something caused the host not to be
3677 found, we end up here, but can detect these cases and handle them specially. */
3679 for (addr = addrlist; addr != NULL; addr = addr->next)
3681 /* If host is not NULL, it means that we stopped processing the host list
3682 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
3683 means we need to behave as if some hosts were skipped because their retry
3684 time had not come. Specifically, this prevents the address from timing out.
3685 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
3686 hosts were tried. */
3690 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
3693 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
3694 "hosts were tried\n");
3699 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
3700 setflag(addr, af_retry_skipped);
3704 if (queue_smtp) /* no deliveries attempted */
3706 addr->transport_return = DEFER;
3707 addr->basic_errno = 0;
3708 addr->message = US"SMTP delivery explicitly queued";
3711 else if (addr->transport_return == DEFER &&
3712 (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0) &&
3713 addr->message == NULL)
3715 addr->basic_errno = ERRNO_HRETRY;
3716 if (continue_hostname != NULL)
3718 addr->message = US"no host found for existing SMTP connection";
3722 setflag(addr, af_pass_message); /* This is not a security risk */
3723 addr->message = (ob->delay_after_cutoff)?
3724 US"retry time not reached for any host after a long failure period" :
3725 US"all hosts have been failing for a long time and were last tried "
3726 "after this message arrived";
3728 /* If we are already using fallback hosts, or there are no fallback hosts
3729 defined, convert the result to FAIL to cause a bounce. */
3731 if (addr->host_list == addr->fallback_hosts ||
3732 addr->fallback_hosts == NULL)
3733 addr->transport_return = FAIL;
3737 if (hosts_retry == hosts_total)
3738 addr->message = US"retry time not reached for any host";
3739 else if (hosts_fail == hosts_total)
3740 addr->message = US"all host address lookups failed permanently";
3741 else if (hosts_defer == hosts_total)
3742 addr->message = US"all host address lookups failed temporarily";
3743 else if (hosts_serial == hosts_total)
3744 addr->message = US"connection limit reached for all hosts";
3745 else if (hosts_fail+hosts_defer == hosts_total)
3746 addr->message = US"all host address lookups failed";
3747 else addr->message = US"some host address lookups failed and retry time "
3748 "not reached for other hosts or connection limit reached";
3753 /* Update the database which keeps information about which messages are waiting
3754 for which hosts to become available. For some message-specific errors, the
3755 update_waiting flag is turned off because we don't want follow-on deliveries in
3756 those cases. If this transport instance is explicitly limited to one message
3757 per connection then follow-on deliveries are not possible and there's no need
3758 to create/update the per-transport wait-<transport_name> database. */
3760 if (update_waiting && tblock->connection_max_messages != 1)
3761 transport_update_waiting(hostlist, tblock->name);
3765 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3767 return TRUE; /* Each address has its status */
3772 /* End of transport/smtp.c */