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 { "address_retry_include_sender", opt_bool,
23 (void *)offsetof(smtp_transport_options_block, address_retry_include_sender) },
24 { "allow_localhost", opt_bool,
25 (void *)offsetof(smtp_transport_options_block, allow_localhost) },
26 { "authenticated_sender", opt_stringptr,
27 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
28 { "authenticated_sender_force", opt_bool,
29 (void *)offsetof(smtp_transport_options_block, authenticated_sender_force) },
30 { "command_timeout", opt_time,
31 (void *)offsetof(smtp_transport_options_block, command_timeout) },
32 { "connect_timeout", opt_time,
33 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
34 { "connection_max_messages", opt_int | opt_public,
35 (void *)offsetof(transport_instance, connection_max_messages) },
36 { "data_timeout", opt_time,
37 (void *)offsetof(smtp_transport_options_block, data_timeout) },
38 { "delay_after_cutoff", opt_bool,
39 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
41 { "dkim_canon", opt_stringptr,
42 (void *)offsetof(smtp_transport_options_block, dkim_canon) },
43 { "dkim_domain", opt_stringptr,
44 (void *)offsetof(smtp_transport_options_block, dkim_domain) },
45 { "dkim_private_key", opt_stringptr,
46 (void *)offsetof(smtp_transport_options_block, dkim_private_key) },
47 { "dkim_selector", opt_stringptr,
48 (void *)offsetof(smtp_transport_options_block, dkim_selector) },
49 { "dkim_sign_headers", opt_stringptr,
50 (void *)offsetof(smtp_transport_options_block, dkim_sign_headers) },
51 { "dkim_strict", opt_stringptr,
52 (void *)offsetof(smtp_transport_options_block, dkim_strict) },
54 { "dns_qualify_single", opt_bool,
55 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
56 { "dns_search_parents", opt_bool,
57 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
58 { "dnssec_request_domains", opt_stringptr,
59 (void *)offsetof(smtp_transport_options_block, dnssec_request_domains) },
60 { "dnssec_require_domains", opt_stringptr,
61 (void *)offsetof(smtp_transport_options_block, dnssec_require_domains) },
62 { "dscp", opt_stringptr,
63 (void *)offsetof(smtp_transport_options_block, dscp) },
64 { "fallback_hosts", opt_stringptr,
65 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
66 { "final_timeout", opt_time,
67 (void *)offsetof(smtp_transport_options_block, final_timeout) },
68 { "gethostbyname", opt_bool,
69 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
71 /* These are no longer honoured, as of Exim 4.80; for now, we silently
72 ignore; 4.83 will warn, and a later-still release will remove
73 these options, so that using them becomes an error. */
74 { "gnutls_require_kx", opt_stringptr,
75 (void *)offsetof(smtp_transport_options_block, gnutls_require_kx) },
76 { "gnutls_require_mac", opt_stringptr,
77 (void *)offsetof(smtp_transport_options_block, gnutls_require_mac) },
78 { "gnutls_require_protocols", opt_stringptr,
79 (void *)offsetof(smtp_transport_options_block, gnutls_require_proto) },
81 { "helo_data", opt_stringptr,
82 (void *)offsetof(smtp_transport_options_block, helo_data) },
83 { "hosts", opt_stringptr,
84 (void *)offsetof(smtp_transport_options_block, hosts) },
85 { "hosts_avoid_esmtp", opt_stringptr,
86 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
87 { "hosts_avoid_pipelining", opt_stringptr,
88 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
90 { "hosts_avoid_tls", opt_stringptr,
91 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
93 { "hosts_max_try", opt_int,
94 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
95 { "hosts_max_try_hardlimit", opt_int,
96 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
98 { "hosts_nopass_tls", opt_stringptr,
99 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
101 { "hosts_override", opt_bool,
102 (void *)offsetof(smtp_transport_options_block, hosts_override) },
103 { "hosts_randomize", opt_bool,
104 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
105 #if defined(SUPPORT_TLS) && !defined(DISABLE_OCSP)
106 { "hosts_request_ocsp", opt_stringptr,
107 (void *)offsetof(smtp_transport_options_block, hosts_request_ocsp) },
109 { "hosts_require_auth", opt_stringptr,
110 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
112 # ifdef EXPERIMENTAL_DANE
113 { "hosts_require_dane", opt_stringptr,
114 (void *)offsetof(smtp_transport_options_block, hosts_require_dane) },
116 # ifndef DISABLE_OCSP
117 { "hosts_require_ocsp", opt_stringptr,
118 (void *)offsetof(smtp_transport_options_block, hosts_require_ocsp) },
120 { "hosts_require_tls", opt_stringptr,
121 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
123 { "hosts_try_auth", opt_stringptr,
124 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
125 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
126 { "hosts_try_dane", opt_stringptr,
127 (void *)offsetof(smtp_transport_options_block, hosts_try_dane) },
130 { "hosts_try_prdr", opt_stringptr,
131 (void *)offsetof(smtp_transport_options_block, hosts_try_prdr) },
134 { "hosts_verify_avoid_tls", opt_stringptr,
135 (void *)offsetof(smtp_transport_options_block, hosts_verify_avoid_tls) },
137 { "interface", opt_stringptr,
138 (void *)offsetof(smtp_transport_options_block, interface) },
139 { "keepalive", opt_bool,
140 (void *)offsetof(smtp_transport_options_block, keepalive) },
141 { "lmtp_ignore_quota", opt_bool,
142 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
143 { "max_rcpt", opt_int | opt_public,
144 (void *)offsetof(transport_instance, max_addresses) },
145 { "multi_domain", opt_bool | opt_public,
146 (void *)offsetof(transport_instance, multi_domain) },
147 { "port", opt_stringptr,
148 (void *)offsetof(smtp_transport_options_block, port) },
149 { "protocol", opt_stringptr,
150 (void *)offsetof(smtp_transport_options_block, protocol) },
151 { "retry_include_ip_address", opt_bool,
152 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
153 { "serialize_hosts", opt_stringptr,
154 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
155 { "size_addition", opt_int,
156 (void *)offsetof(smtp_transport_options_block, size_addition) }
158 ,{ "tls_certificate", opt_stringptr,
159 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
160 { "tls_crl", opt_stringptr,
161 (void *)offsetof(smtp_transport_options_block, tls_crl) },
162 { "tls_dh_min_bits", opt_int,
163 (void *)offsetof(smtp_transport_options_block, tls_dh_min_bits) },
164 { "tls_privatekey", opt_stringptr,
165 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
166 { "tls_require_ciphers", opt_stringptr,
167 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
168 { "tls_sni", opt_stringptr,
169 (void *)offsetof(smtp_transport_options_block, tls_sni) },
170 { "tls_tempfail_tryclear", opt_bool,
171 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
172 { "tls_try_verify_hosts", opt_stringptr,
173 (void *)offsetof(smtp_transport_options_block, tls_try_verify_hosts) },
174 #ifdef EXPERIMENTAL_CERTNAMES
175 { "tls_verify_cert_hostnames", opt_stringptr,
176 (void *)offsetof(smtp_transport_options_block,tls_verify_cert_hostnames)},
178 { "tls_verify_certificates", opt_stringptr,
179 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) },
180 { "tls_verify_hosts", opt_stringptr,
181 (void *)offsetof(smtp_transport_options_block, tls_verify_hosts) }
185 /* Size of the options list. An extern variable has to be used so that its
186 address can appear in the tables drtables.c. */
188 int smtp_transport_options_count =
189 sizeof(smtp_transport_options)/sizeof(optionlist);
191 /* Default private options block for the smtp transport. */
193 smtp_transport_options_block smtp_transport_option_defaults = {
195 NULL, /* fallback_hosts */
197 NULL, /* fallback_hostlist */
198 NULL, /* authenticated_sender */
199 US"$primary_hostname", /* helo_data */
200 NULL, /* interface */
202 US"smtp", /* protocol */
204 NULL, /* serialize_hosts */
205 NULL, /* hosts_try_auth */
206 NULL, /* hosts_require_auth */
207 #ifdef EXPERIMENTAL_DANE
208 NULL, /* hosts_try_dane */
209 NULL, /* hosts_require_dane */
212 NULL, /* hosts_try_prdr */
215 US"*", /* hosts_request_ocsp (except under DANE; tls_client_start()) */
216 NULL, /* hosts_require_ocsp */
218 NULL, /* hosts_require_tls */
219 NULL, /* hosts_avoid_tls */
220 US"*", /* hosts_verify_avoid_tls */
221 NULL, /* hosts_avoid_pipelining */
222 NULL, /* hosts_avoid_esmtp */
223 NULL, /* hosts_nopass_tls */
224 5*60, /* command_timeout */
225 5*60, /* connect_timeout; shorter system default overrides */
226 5*60, /* data timeout */
227 10*60, /* final timeout */
228 1024, /* size_addition */
229 5, /* hosts_max_try */
230 50, /* hosts_max_try_hardlimit */
231 TRUE, /* address_retry_include_sender */
232 FALSE, /* allow_localhost */
233 FALSE, /* authenticated_sender_force */
234 FALSE, /* gethostbyname */
235 TRUE, /* dns_qualify_single */
236 FALSE, /* dns_search_parents */
237 NULL, /* dnssec_request_domains */
238 NULL, /* dnssec_require_domains */
239 TRUE, /* delay_after_cutoff */
240 FALSE, /* hosts_override */
241 FALSE, /* hosts_randomize */
242 TRUE, /* keepalive */
243 FALSE, /* lmtp_ignore_quota */
244 TRUE /* retry_include_ip_address */
246 ,NULL, /* tls_certificate */
248 NULL, /* tls_privatekey */
249 NULL, /* tls_require_ciphers */
250 NULL, /* gnutls_require_kx */
251 NULL, /* gnutls_require_mac */
252 NULL, /* gnutls_require_proto */
254 NULL, /* tls_verify_certificates */
255 EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
256 /* tls_dh_min_bits */
257 TRUE, /* tls_tempfail_tryclear */
258 NULL, /* tls_verify_hosts */
259 NULL /* tls_try_verify_hosts */
260 # ifdef EXPERIMENTAL_CERTNAMES
261 ,NULL /* tls_verify_cert_hostnames */
265 ,NULL, /* dkim_canon */
266 NULL, /* dkim_domain */
267 NULL, /* dkim_private_key */
268 NULL, /* dkim_selector */
269 NULL, /* dkim_sign_headers */
270 NULL /* dkim_strict */
274 #ifdef EXPERIMENTAL_DSN
275 /* some DSN flags for use later */
277 static int rf_list[] = {rf_notify_never, rf_notify_success,
278 rf_notify_failure, rf_notify_delay };
280 static uschar *rf_names[] = { "NEVER", "SUCCESS", "FAILURE", "DELAY" };
287 static uschar *smtp_command; /* Points to last cmd for error messages */
288 static uschar *mail_command; /* Points to MAIL cmd for error messages */
289 static BOOL update_waiting; /* TRUE to update the "wait" database */
292 /*************************************************
293 * Setup entry point *
294 *************************************************/
296 /* This function is called when the transport is about to be used,
297 but before running it in a sub-process. It is used for two things:
299 (1) To set the fallback host list in addresses, when delivering.
300 (2) To pass back the interface, port, protocol, and other options, for use
301 during callout verification.
304 tblock pointer to the transport instance block
305 addrlist list of addresses about to be transported
306 tf if not NULL, pointer to block in which to return options
307 uid the uid that will be set (not used)
308 gid the gid that will be set (not used)
309 errmsg place for error message (not used)
311 Returns: OK always (FAIL, DEFER not used)
315 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
316 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
318 smtp_transport_options_block *ob =
319 (smtp_transport_options_block *)(tblock->options_block);
321 errmsg = errmsg; /* Keep picky compilers happy */
325 /* Pass back options if required. This interface is getting very messy. */
329 tf->interface = ob->interface;
331 tf->protocol = ob->protocol;
332 tf->hosts = ob->hosts;
333 tf->hosts_override = ob->hosts_override;
334 tf->hosts_randomize = ob->hosts_randomize;
335 tf->gethostbyname = ob->gethostbyname;
336 tf->qualify_single = ob->dns_qualify_single;
337 tf->search_parents = ob->dns_search_parents;
338 tf->helo_data = ob->helo_data;
341 /* Set the fallback host list for all the addresses that don't have fallback
342 host lists, provided that the local host wasn't present in the original host
345 if (!testflag(addrlist, af_local_host_removed))
347 for (; addrlist != NULL; addrlist = addrlist->next)
348 if (addrlist->fallback_hosts == NULL)
349 addrlist->fallback_hosts = ob->fallback_hostlist;
357 /*************************************************
358 * Initialization entry point *
359 *************************************************/
361 /* Called for each instance, after its options have been read, to
362 enable consistency checks to be done, or anything else that needs
365 Argument: pointer to the transport instance block
370 smtp_transport_init(transport_instance *tblock)
372 smtp_transport_options_block *ob =
373 (smtp_transport_options_block *)(tblock->options_block);
375 /* Retry_use_local_part defaults FALSE if unset */
377 if (tblock->retry_use_local_part == TRUE_UNSET)
378 tblock->retry_use_local_part = FALSE;
380 /* Set the default port according to the protocol */
382 if (ob->port == NULL)
383 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
384 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
386 /* Set up the setup entry point, to be called before subprocesses for this
389 tblock->setup = smtp_transport_setup;
391 /* Complain if any of the timeouts are zero. */
393 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
394 ob->final_timeout <= 0)
395 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
396 "command, data, or final timeout value is zero for %s transport",
399 /* If hosts_override is set and there are local hosts, set the global
400 flag that stops verify from showing router hosts. */
402 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
404 /* If there are any fallback hosts listed, build a chain of host items
405 for them, but do not do any lookups at this time. */
407 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
410 if ( ob->gnutls_require_kx
411 || ob->gnutls_require_mac
412 || ob->gnutls_require_proto)
413 log_write(0, LOG_MAIN, "WARNING: smtp transport options"
414 " gnutls_require_kx, gnutls_require_mac and gnutls_require_protocols"
423 /*************************************************
424 * Set delivery info into all active addresses *
425 *************************************************/
427 /* Only addresses whose status is >= PENDING are relevant. A lesser
428 status means that an address is not currently being processed.
431 addrlist points to a chain of addresses
432 errno_value to put in each address's errno field
433 msg to put in each address's message field
434 rc to put in each address's transport_return field
435 pass_message if TRUE, set the "pass message" flag in the address
436 host if set, mark addrs as having used this host
438 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
439 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
440 this particular type of timeout.
446 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
447 BOOL pass_message, host_item * host)
451 if (errno_value == ERRNO_CONNECTTIMEOUT)
453 errno_value = ETIMEDOUT;
454 orvalue = RTEF_CTOUT;
456 for (addr = addrlist; addr != NULL; addr = addr->next)
458 if (addr->transport_return < PENDING) continue;
459 addr->basic_errno = errno_value;
460 addr->more_errno |= orvalue;
464 if (pass_message) setflag(addr, af_pass_message);
466 addr->transport_return = rc;
468 addr->host_used = host;
474 /*************************************************
475 * Check an SMTP response *
476 *************************************************/
478 /* This function is given an errno code and the SMTP response buffer
479 to analyse, together with the host identification for generating messages. It
480 sets an appropriate message and puts the first digit of the response code into
481 the yield variable. If no response was actually read, a suitable digit is
485 host the current host, to get its name for messages
486 errno_value pointer to the errno value
487 more_errno from the top address for use with ERRNO_FILTER_FAIL
488 buffer the SMTP response buffer
489 yield where to put a one-digit SMTP response code
490 message where to put an errror message
491 pass_message set TRUE if message is an SMTP response
493 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
497 check_response(host_item *host, int *errno_value, int more_errno,
498 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
502 if (smtp_use_pipelining &&
503 (Ustrcmp(smtp_command, "MAIL") == 0 ||
504 Ustrcmp(smtp_command, "RCPT") == 0 ||
505 Ustrcmp(smtp_command, "DATA") == 0))
508 *yield = '4'; /* Default setting is to give a temporary error */
510 /* Handle response timeout */
512 if (*errno_value == ETIMEDOUT)
514 *message = US string_sprintf("SMTP timeout after %s%s",
516 if (transport_count > 0)
517 *message = US string_sprintf("%s (%d bytes written)", *message,
522 /* Handle malformed SMTP response */
524 if (*errno_value == ERRNO_SMTPFORMAT)
526 uschar *malfresp = string_printing(buffer);
527 while (isspace(*malfresp)) malfresp++;
528 *message = *malfresp == 0
529 ? string_sprintf("Malformed SMTP reply (an empty line) "
530 "in response to %s%s", pl, smtp_command)
531 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
532 pl, smtp_command, malfresp);
536 /* Handle a failed filter process error; can't send QUIT as we mustn't
539 if (*errno_value == ERRNO_FILTER_FAIL)
541 *message = US string_sprintf("transport filter process failed (%d)%s",
543 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
547 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
550 if (*errno_value == ERRNO_CHHEADER_FAIL)
553 US string_sprintf("failed to expand headers_add or headers_remove: %s",
554 expand_string_message);
558 /* Handle failure to write a complete data block */
560 if (*errno_value == ERRNO_WRITEINCOMPLETE)
562 *message = US string_sprintf("failed to write a data block");
566 /* Handle error responses from the remote mailer. */
570 uschar *s = string_printing(buffer);
571 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
572 "%s", pl, smtp_command, s);
573 *pass_message = TRUE;
578 /* No data was read. If there is no errno, this must be the EOF (i.e.
579 connection closed) case, which causes deferral. An explicit connection reset
580 error has the same effect. Otherwise, put the host's identity in the message,
581 leaving the errno value to be interpreted as well. In all cases, we have to
582 assume the connection is now dead. */
584 if (*errno_value == 0 || *errno_value == ECONNRESET)
586 *errno_value = ERRNO_SMTPCLOSED;
587 *message = US string_sprintf("Remote host closed connection "
588 "in response to %s%s", pl, smtp_command);
590 else *message = US string_sprintf("%s [%s]", host->name, host->address);
597 /*************************************************
598 * Write error message to logs *
599 *************************************************/
601 /* This writes to the main log and to the message log.
604 addr the address item containing error information
605 host the current host
611 write_logs(address_item *addr, host_item *host)
613 uschar * message = string_sprintf("H=%s [%s]", host->name, host->address);
617 message = string_sprintf("%s: %s", message, addr->message);
618 if (addr->basic_errno > 0)
619 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
620 log_write(0, LOG_MAIN, "%s", message);
621 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
625 if (log_extra_selector & LX_outgoing_port)
626 message = string_sprintf("%s:%d", message,
627 host->port == PORT_NONE ? 25 : host->port);
628 log_write(0, LOG_MAIN, "%s %s", message, strerror(addr->basic_errno));
629 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), message,
630 strerror(addr->basic_errno));
635 msglog_line(host_item * host, uschar * message)
637 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
638 host->name, host->address, message);
643 #ifdef EXPERIMENTAL_EVENT
644 /*************************************************
645 * Post-defer action *
646 *************************************************/
648 /* This expands an arbitrary per-transport string.
649 It might, for example, be used to write to the database log.
652 addr the address item containing error information
653 host the current host
659 deferred_event_raise(address_item *addr, host_item *host)
661 uschar * action = addr->transport->event_action;
662 uschar * save_domain;
668 save_domain = deliver_domain;
669 save_local = deliver_localpart;
671 /*XXX would ip & port already be set up? */
672 deliver_host_address = string_copy(host->address);
673 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
674 event_defer_errno = addr->basic_errno;
676 router_name = addr->router->name;
677 transport_name = addr->transport->name;
678 deliver_domain = addr->domain;
679 deliver_localpart = addr->local_part;
681 (void) event_raise(action, US"msg:host:defer",
683 ? addr->basic_errno > 0
684 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
685 : string_copy(addr->message)
686 : addr->basic_errno > 0
687 ? string_copy(US strerror(addr->basic_errno))
690 deliver_localpart = save_local;
691 deliver_domain = save_domain;
692 router_name = transport_name = NULL;
698 /*************************************************
699 * Synchronize SMTP responses *
700 *************************************************/
702 /* This function is called from smtp_deliver() to receive SMTP responses from
703 the server, and match them up with the commands to which they relate. When
704 PIPELINING is not in use, this function is called after every command, and is
705 therefore somewhat over-engineered, but it is simpler to use a single scheme
706 that works both with and without PIPELINING instead of having two separate sets
709 The set of commands that are buffered up with pipelining may start with MAIL
710 and may end with DATA; in between are RCPT commands that correspond to the
711 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
712 etc.) are never buffered.
714 Errors after MAIL or DATA abort the whole process leaving the response in the
715 buffer. After MAIL, pending responses are flushed, and the original command is
716 re-instated in big_buffer for error messages. For RCPT commands, the remote is
717 permitted to reject some recipient addresses while accepting others. However
718 certain errors clearly abort the whole process. Set the value in
719 transport_return to PENDING_OK if the address is accepted. If there is a
720 subsequent general error, it will get reset accordingly. If not, it will get
721 converted to OK at the end.
724 addrlist the complete address list
725 include_affixes TRUE if affixes include in RCPT
726 sync_addr ptr to the ptr of the one to start scanning at (updated)
727 host the host we are connected to
728 count the number of responses to read
730 include_sender true if 4xx retry is to include the sender it its key
731 pending_MAIL true if the first response is for MAIL
732 pending_DATA 0 if last command sent was not DATA
733 +1 if previously had a good recipient
734 -1 if not previously had a good recipient
735 inblock incoming SMTP block
736 timeout timeout value
737 buffer buffer for reading response
738 buffsize size of buffer
740 Returns: 3 if at least one address had 2xx and one had 5xx
741 2 if at least one address had 5xx but none had 2xx
742 1 if at least one host had a 2xx response, but none had 5xx
743 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
744 -1 timeout while reading RCPT response
745 -2 I/O or other non-response error for RCPT
746 -3 DATA or MAIL failed - errno and buffer set
750 sync_responses(address_item *addrlist, BOOL include_affixes,
751 address_item **sync_addr, host_item *host, int count,
752 BOOL address_retry_include_sender, BOOL pending_MAIL,
753 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
756 address_item *addr = *sync_addr;
759 /* Handle the response for a MAIL command. On error, reinstate the original
760 command in big_buffer for error message use, and flush any further pending
761 responses before returning, except after I/O errors and timeouts. */
766 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
768 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
769 if (errno == 0 && buffer[0] != 0)
771 uschar flushbuffer[4096];
773 if (buffer[0] == '4')
775 save_errno = ERRNO_MAIL4XX;
776 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
780 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
782 && (errno != 0 || flushbuffer[0] == 0))
788 if (pending_DATA) count--; /* Number of RCPT responses to come */
789 while (count-- > 0) /* Mark any pending addrs with the host used */
791 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
792 addr->host_used = host;
799 if (pending_DATA) count--; /* Number of RCPT responses to come */
801 /* Read and handle the required number of RCPT responses, matching each one up
802 with an address by scanning for the next address whose status is PENDING_DEFER.
807 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
809 /* The address was accepted */
810 addr->host_used = host;
812 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
815 addr->transport_return = PENDING_OK;
817 /* If af_dr_retry_exists is set, there was a routing delay on this address;
818 ensure that any address-specific retry record is expunged. We do this both
819 for the basic key and for the version that also includes the sender. */
821 if (testflag(addr, af_dr_retry_exists))
823 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
825 retry_add_item(addr, altkey, rf_delete);
826 retry_add_item(addr, addr->address_retry_key, rf_delete);
830 /* Timeout while reading the response */
832 else if (errno == ETIMEDOUT)
834 int save_errno = errno;
835 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
836 transport_rcpt_address(addr, include_affixes));
837 set_errno(addrlist, save_errno, message, DEFER, FALSE, NULL);
838 retry_add_item(addr, addr->address_retry_key, 0);
839 update_waiting = FALSE;
843 /* Handle other errors in obtaining an SMTP response by returning -1. This
844 will cause all the addresses to be deferred. Restore the SMTP command in
845 big_buffer for which we are checking the response, so the error message
848 else if (errno != 0 || buffer[0] == 0)
850 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
851 transport_rcpt_address(addr, include_affixes));
855 /* Handle SMTP permanent and temporary response codes. */
860 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
861 "%s", transport_rcpt_address(addr, include_affixes),
862 string_printing(buffer));
863 setflag(addr, af_pass_message);
864 msglog_line(host, addr->message);
866 /* The response was 5xx */
868 if (buffer[0] == '5')
870 addr->transport_return = FAIL;
874 /* The response was 4xx */
878 addr->transport_return = DEFER;
879 addr->basic_errno = ERRNO_RCPT4XX;
880 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
882 /* Log temporary errors if there are more hosts to be tried.
883 If not, log this last one in the == line. */
886 log_write(0, LOG_MAIN, "H=%s [%s]: %s", host->name, host->address, addr->message);
888 /* Do not put this message on the list of those waiting for specific
889 hosts, as otherwise it is likely to be tried too often. */
891 update_waiting = FALSE;
893 /* Add a retry item for the address so that it doesn't get tried again
894 too soon. If address_retry_include_sender is true, add the sender address
897 if (address_retry_include_sender)
899 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
901 retry_add_item(addr, altkey, 0);
903 else retry_add_item(addr, addr->address_retry_key, 0);
906 } /* Loop for next RCPT response */
908 /* Update where to start at for the next block of responses, unless we
909 have already handled all the addresses. */
911 if (addr != NULL) *sync_addr = addr->next;
913 /* Handle a response to DATA. If we have not had any good recipients, either
914 previously or in this block, the response is ignored. */
916 if (pending_DATA != 0 &&
917 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
922 if (pending_DATA > 0 || (yield & 1) != 0)
924 if (errno == 0 && buffer[0] == '4')
926 errno = ERRNO_DATA4XX;
927 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
931 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
932 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
933 "is in use and there were no good recipients\n", msg);
936 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
937 present) received 3xx. If any RCPTs were handled and yielded anything other
938 than 4xx, yield will be set non-zero. */
945 /* Do the client side of smtp-level authentication */
948 buffer EHLO response from server (gets overwritten)
949 addrlist chain of potential addresses to deliver
950 host host to deliver to
952 ibp, obp comms channel control blocks
955 OK Success, or failed (but not required): global "smtp_authenticated" set
956 DEFER Failed authentication (and was required)
957 ERROR Internal problem
959 FAIL_SEND Failed communications - transmit
964 smtp_auth(uschar *buffer, unsigned bufsize, address_item *addrlist, host_item *host,
965 smtp_transport_options_block *ob, BOOL is_esmtp,
966 smtp_inblock *ibp, smtp_outblock *obp)
969 uschar *fail_reason = US"server did not advertise AUTH support";
971 smtp_authenticated = FALSE;
972 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
973 require_auth = verify_check_this_host(&(ob->hosts_require_auth), NULL,
974 host->name, host->address, NULL);
976 if (is_esmtp && !regex_AUTH) regex_AUTH =
977 regex_must_compile(US"\\n250[\\s\\-]AUTH\\s+([\\-\\w\\s]+)(?:\\n|$)",
980 if (is_esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
982 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
983 expand_nmax = -1; /* reset */
985 /* Must not do this check until after we have saved the result of the
986 regex match above. */
988 if (require_auth == OK ||
989 verify_check_this_host(&(ob->hosts_try_auth), NULL, host->name,
990 host->address, NULL) == OK)
993 fail_reason = US"no common mechanisms were found";
995 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
997 /* Scan the configured authenticators looking for one which is configured
998 for use as a client, which is not suppressed by client_condition, and
999 whose name matches an authentication mechanism supported by the server.
1000 If one is found, attempt to authenticate by calling its client function.
1003 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1007 (au->client_condition != NULL &&
1008 !expand_check_condition(au->client_condition, au->name,
1009 US"client authenticator")))
1011 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1013 (au->client)? "client_condition is false" :
1014 "not configured as a client");
1018 /* Loop to scan supported server mechanisms */
1023 int len = Ustrlen(au->public_name);
1024 while (isspace(*p)) p++;
1026 if (strncmpic(au->public_name, p, len) != 0 ||
1027 (p[len] != 0 && !isspace(p[len])))
1029 while (*p != 0 && !isspace(*p)) p++;
1033 /* Found data for a listed mechanism. Call its client entry. Set
1034 a flag in the outblock so that data is overwritten after sending so
1035 that reflections don't show it. */
1037 fail_reason = US"authentication attempt(s) failed";
1038 obp->authenticating = TRUE;
1039 rc = (au->info->clientcode)(au, ibp, obp,
1040 ob->command_timeout, buffer, bufsize);
1041 obp->authenticating = FALSE;
1042 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1045 /* A temporary authentication failure must hold up delivery to
1046 this host. After a permanent authentication failure, we carry on
1047 to try other authentication methods. If all fail hard, try to
1048 deliver the message unauthenticated unless require_auth was set. */
1053 smtp_authenticated = TRUE; /* stops the outer loop */
1054 client_authenticator = au->name;
1055 if (au->set_client_id != NULL)
1056 client_authenticated_id = expand_string(au->set_client_id);
1059 /* Failure after writing a command */
1064 /* Failure after reading a response */
1067 if (errno != 0 || buffer[0] != '5') return FAIL;
1068 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1069 au->name, host->name, host->address, buffer);
1072 /* Failure by some other means. In effect, the authenticator
1073 decided it wasn't prepared to handle this case. Typically this
1074 is the result of "fail" in an expansion string. Do we need to
1075 log anything here? Feb 2006: a message is now put in the buffer
1076 if logging is required. */
1080 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1081 "authentication H=%s [%s] %s", au->name, host->name,
1082 host->address, buffer);
1085 /* Internal problem, message in buffer. */
1088 set_errno(addrlist, 0, string_copy(buffer), DEFER, FALSE, NULL);
1092 break; /* If not authenticated, try next authenticator */
1093 } /* Loop for scanning supported server mechanisms */
1094 } /* Loop for further authenticators */
1098 /* If we haven't authenticated, but are required to, give up. */
1100 if (require_auth == OK && !smtp_authenticated)
1102 set_errno(addrlist, ERRNO_AUTHFAIL,
1103 string_sprintf("authentication required but %s", fail_reason), DEFER,
1112 /* Construct AUTH appendix string for MAIL TO */
1115 buffer to build string
1116 addrlist chain of potential addresses to deliver
1117 ob transport options
1119 Globals smtp_authenticated
1120 client_authenticated_sender
1121 Return True on error, otherwise buffer has (possibly empty) terminated string
1125 smtp_mail_auth_str(uschar *buffer, unsigned bufsize, address_item *addrlist,
1126 smtp_transport_options_block *ob)
1128 uschar *local_authenticated_sender = authenticated_sender;
1131 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n", authenticated_sender, ob->authenticated_sender, smtp_authenticated?"Y":"N");
1134 if (ob->authenticated_sender != NULL)
1136 uschar *new = expand_string(ob->authenticated_sender);
1139 if (!expand_string_forcedfail)
1141 uschar *message = string_sprintf("failed to expand "
1142 "authenticated_sender: %s", expand_string_message);
1143 set_errno(addrlist, 0, message, DEFER, FALSE, NULL);
1147 else if (new[0] != 0) local_authenticated_sender = new;
1150 /* Add the authenticated sender address if present */
1152 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1153 local_authenticated_sender != NULL)
1155 string_format(buffer, bufsize, " AUTH=%s",
1156 auth_xtextencode(local_authenticated_sender,
1157 Ustrlen(local_authenticated_sender)));
1158 client_authenticated_sender = string_copy(local_authenticated_sender);
1168 #ifdef EXPERIMENTAL_DANE
1170 tlsa_lookup(host_item * host, dns_answer * dnsa,
1171 BOOL dane_required, BOOL * dane)
1173 /* move this out to host.c given the similarity to dns_lookup() ? */
1175 uschar * fullname = buffer;
1177 /* TLSA lookup string */
1178 (void)sprintf(CS buffer, "_%d._tcp.%.256s", host->port, host->name);
1180 switch (dns_lookup(dnsa, buffer, T_TLSA, &fullname))
1183 return DEFER; /* just defer this TLS'd conn */
1189 log_write(0, LOG_MAIN, "DANE error: TLSA lookup failed");
1195 if (!dns_is_secure(dnsa))
1197 log_write(0, LOG_MAIN, "DANE error: TLSA lookup not DNSSEC");
1208 /*************************************************
1209 * Deliver address list to given host *
1210 *************************************************/
1212 /* If continue_hostname is not null, we get here only when continuing to
1213 deliver down an existing channel. The channel was passed as the standard
1214 input. TLS is never active on a passed channel; the previous process always
1215 closes it down before passing the connection on.
1217 Otherwise, we have to make a connection to the remote host, and do the
1218 initial protocol exchange.
1220 When running as an MUA wrapper, if the sender or any recipient is rejected,
1221 temporarily or permanently, we force failure for all recipients.
1224 addrlist chain of potential addresses to deliver; only those whose
1225 transport_return field is set to PENDING_DEFER are currently
1226 being processed; others should be skipped - they have either
1227 been delivered to an earlier host or IP address, or been
1228 failed by one of them.
1229 host host to deliver to
1230 host_af AF_INET or AF_INET6
1231 port default TCP/IP port to use, in host byte order
1232 interface interface to bind to, or NULL
1233 tblock transport instance block
1234 copy_host TRUE if host set in addr->host_used must be copied, because
1235 it is specific to this call of the transport
1236 message_defer set TRUE if yield is OK, but all addresses were deferred
1237 because of a non-recipient, non-host failure, that is, a
1238 4xx response to MAIL FROM, DATA, or ".". This is a defer
1239 that is specific to the message.
1240 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1241 a second attempt after TLS initialization fails
1243 Returns: OK - the connection was made and the delivery attempted;
1244 the result for each address is in its data block.
1245 DEFER - the connection could not be made, or something failed
1246 while setting up the SMTP session, or there was a
1247 non-message-specific error, such as a timeout.
1248 ERROR - a filter command is specified for this transport,
1249 and there was a problem setting it up; OR helo_data
1250 or add_headers or authenticated_sender is specified
1251 for this transport, and the string failed to expand
1255 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
1256 uschar *interface, transport_instance *tblock, BOOL copy_host,
1257 BOOL *message_defer, BOOL suppress_tls)
1260 address_item *sync_addr;
1261 address_item *first_addr = addrlist;
1266 time_t start_delivery_time = time(NULL);
1267 smtp_transport_options_block *ob =
1268 (smtp_transport_options_block *)(tblock->options_block);
1269 BOOL lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
1270 BOOL smtps = strcmpic(ob->protocol, US"smtps") == 0;
1272 BOOL send_rset = TRUE;
1273 BOOL send_quit = TRUE;
1274 BOOL setting_up = TRUE;
1275 BOOL completed_address = FALSE;
1278 BOOL pass_message = FALSE;
1279 #ifndef DISABLE_PRDR
1280 BOOL prdr_offered = FALSE;
1283 #ifdef EXPERIMENTAL_DSN
1284 BOOL dsn_all_lasthop = TRUE;
1286 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1288 dns_answer tlsa_dnsa;
1290 smtp_inblock inblock;
1291 smtp_outblock outblock;
1292 int max_rcpt = tblock->max_addresses;
1293 uschar *igquotstr = US"";
1294 uschar *helo_data = NULL;
1295 uschar *message = NULL;
1296 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
1298 uschar buffer[4096];
1299 uschar inbuffer[4096];
1300 uschar outbuffer[4096];
1302 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
1304 *message_defer = FALSE;
1305 smtp_command = US"initial connection";
1306 if (max_rcpt == 0) max_rcpt = 999999;
1308 /* Set up the buffer for reading SMTP response packets. */
1310 inblock.buffer = inbuffer;
1311 inblock.buffersize = sizeof(inbuffer);
1312 inblock.ptr = inbuffer;
1313 inblock.ptrend = inbuffer;
1315 /* Set up the buffer for holding SMTP commands while pipelining */
1317 outblock.buffer = outbuffer;
1318 outblock.buffersize = sizeof(outbuffer);
1319 outblock.ptr = outbuffer;
1320 outblock.cmd_count = 0;
1321 outblock.authenticating = FALSE;
1323 /* Reset the parameters of a TLS session. */
1326 tls_out.cipher = NULL; /* the one we may use for this transport */
1327 tls_out.ourcert = NULL;
1328 tls_out.peercert = NULL;
1329 tls_out.peerdn = NULL;
1330 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1333 tls_out.ocsp = OCSP_NOT_REQ;
1335 /* Flip the legacy TLS-related variables over to the outbound set in case
1336 they're used in the context of the transport. Don't bother resetting
1337 afterward as we're in a subprocess. */
1339 tls_modify_variables(&tls_out);
1344 set_errno(addrlist, 0, US"TLS support not available", DEFER, FALSE, NULL);
1349 /* Make a connection to the host if this isn't a continued delivery, and handle
1350 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
1351 specially so they can be identified for retries. */
1353 if (continue_hostname == NULL)
1355 /* This puts port into host->port */
1356 inblock.sock = outblock.sock =
1357 smtp_connect(host, host_af, port, interface, ob->connect_timeout,
1358 ob->keepalive, ob->dscp
1359 #ifdef EXPERIMENTAL_EVENT
1360 , tblock->event_action
1364 if (inblock.sock < 0)
1366 set_errno(addrlist, (errno == ETIMEDOUT)? ERRNO_CONNECTTIMEOUT : errno,
1367 NULL, DEFER, FALSE, NULL);
1371 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1375 tls_out.dane_verified = FALSE;
1376 tls_out.tlsa_usage = 0;
1378 dane_required = verify_check_this_host(&ob->hosts_require_dane, NULL,
1379 host->name, host->address, NULL) == OK;
1381 if (host->dnssec == DS_YES)
1384 || verify_check_this_host(&ob->hosts_try_dane, NULL,
1385 host->name, host->address, NULL) == OK
1387 if ((rc = tlsa_lookup(host, &tlsa_dnsa, dane_required, &dane)) != OK)
1390 else if (dane_required)
1392 log_write(0, LOG_MAIN, "DANE error: %s lookup not DNSSEC", host->name);
1397 ob->tls_tempfail_tryclear = FALSE;
1401 /* Expand the greeting message while waiting for the initial response. (Makes
1402 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1403 delayed till here so that $sending_interface and $sending_port are set. */
1405 helo_data = expand_string(ob->helo_data);
1407 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1408 is nevertheless a reasonably clean way of programming this kind of logic,
1409 where you want to escape on any error. */
1413 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1414 ob->command_timeout)) goto RESPONSE_FAILED;
1416 #ifdef EXPERIMENTAL_EVENT
1419 lookup_dnssec_authenticated = host->dnssec==DS_YES ? US"yes"
1420 : host->dnssec==DS_NO ? US"no" : NULL;
1421 s = event_raise(tblock->event_action, US"smtp:connect", buffer);
1424 set_errno(addrlist, 0,
1425 string_sprintf("deferred by smtp:connect event expansion: %s", s),
1426 DEFER, FALSE, NULL);
1433 /* Now check if the helo_data expansion went well, and sign off cleanly if
1436 if (helo_data == NULL)
1438 uschar *message = string_sprintf("failed to expand helo_data: %s",
1439 expand_string_message);
1440 set_errno(addrlist, 0, message, DEFER, FALSE, NULL);
1446 /** Debugging without sending a message
1447 addrlist->transport_return = DEFER;
1451 /* Errors that occur after this point follow an SMTP command, which is
1452 left in big_buffer by smtp_write_command() for use in error messages. */
1454 smtp_command = big_buffer;
1456 /* Tell the remote who we are...
1458 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1459 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1460 greeting is of this form. The assumption was that the far end supports it
1461 properly... but experience shows that there are some that give 5xx responses,
1462 even though the banner includes "ESMTP" (there's a bloody-minded one that
1463 says "ESMTP not spoken here"). Cope with that case.
1465 September 2000: Time has passed, and it seems reasonable now to always send
1466 EHLO at the start. It is also convenient to make the change while installing
1469 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1470 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1471 would be no way to send out the mails, so there is now a host list
1472 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1473 PIPELINING problem as well. Maybe it can also be useful to cure other
1474 problems with broken servers.
1476 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1477 Then somebody tried it with a Microsoft mailer... It seems that all other
1478 mailers use upper case for some reason (the RFC is quite clear about case
1479 independence) so, for peace of mind, I gave in. */
1481 esmtp = verify_check_this_host(&(ob->hosts_avoid_esmtp), NULL,
1482 host->name, host->address, NULL) != OK;
1484 /* Alas; be careful, since this goto is not an error-out, so conceivably
1485 we might set data between here and the target which we assume to exist
1486 and be usable. I can see this coming back to bite us. */
1491 suppress_tls = FALSE;
1492 ob->tls_tempfail_tryclear = FALSE;
1493 smtp_command = US"SSL-on-connect";
1500 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1501 lmtp? "LHLO" : "EHLO", helo_data) < 0)
1503 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1504 ob->command_timeout))
1506 if (errno != 0 || buffer[0] == 0 || lmtp) goto RESPONSE_FAILED;
1513 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1518 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1520 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1521 ob->command_timeout)) goto RESPONSE_FAILED;
1524 /* Set IGNOREQUOTA if the response to LHLO specifies support and the
1525 lmtp_ignore_quota option was set. */
1527 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1528 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1529 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1531 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1534 tls_offered = esmtp &&
1535 pcre_exec(regex_STARTTLS, NULL, CS buffer, Ustrlen(buffer), 0,
1536 PCRE_EOPT, NULL, 0) >= 0;
1539 #ifndef DISABLE_PRDR
1540 prdr_offered = esmtp &&
1541 (pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(buffer), 0,
1542 PCRE_EOPT, NULL, 0) >= 0) &&
1543 (verify_check_this_host(&(ob->hosts_try_prdr), NULL, host->name,
1544 host->address, NULL) == OK);
1547 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1551 /* For continuing deliveries down the same channel, the socket is the standard
1552 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1553 below). Set up the pointer to where subsequent commands will be left, for
1554 error messages. Note that smtp_use_size and smtp_use_pipelining will have been
1555 set from the command line if they were set in the process that passed the
1560 inblock.sock = outblock.sock = fileno(stdin);
1561 smtp_command = big_buffer;
1562 host->port = port; /* Record the port that was used */
1565 /* If TLS is available on this connection, whether continued or not, attempt to
1566 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1567 send another EHLO - the server may give a different answer in secure mode. We
1568 use a separate buffer for reading the response to STARTTLS so that if it is
1569 negative, the original EHLO data is available for subsequent analysis, should
1570 the client not be required to use TLS. If the response is bad, copy the buffer
1571 for error analysis. */
1574 if (tls_offered && !suppress_tls &&
1575 verify_check_this_host(&(ob->hosts_avoid_tls), NULL, host->name,
1576 host->address, NULL) != OK)
1578 uschar buffer2[4096];
1579 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1582 /* If there is an I/O error, transmission of this message is deferred. If
1583 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1584 false, we also defer. However, if there is a temporary rejection of STARTTLS
1585 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1586 STARTTLS, we carry on. This means we will try to send the message in clear,
1587 unless the host is in hosts_require_tls (tested below). */
1589 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1590 ob->command_timeout))
1592 if (errno != 0 || buffer2[0] == 0 ||
1593 (buffer2[0] == '4' && !ob->tls_tempfail_tryclear))
1595 Ustrncpy(buffer, buffer2, sizeof(buffer));
1596 goto RESPONSE_FAILED;
1600 /* STARTTLS accepted: try to negotiate a TLS session. */
1605 int rc = tls_client_start(inblock.sock, host, addrlist, tblock
1606 # ifdef EXPERIMENTAL_DANE
1607 , dane ? &tlsa_dnsa : NULL
1611 /* TLS negotiation failed; give an error. From outside, this function may
1612 be called again to try in clear on a new connection, if the options permit
1613 it for this host. */
1617 save_errno = ERRNO_TLSFAILURE;
1618 message = US"failure while setting up TLS session";
1623 /* TLS session is set up */
1625 for (addr = addrlist; addr != NULL; addr = addr->next)
1626 if (addr->transport_return == PENDING_DEFER)
1628 addr->cipher = tls_out.cipher;
1629 addr->ourcert = tls_out.ourcert;
1630 addr->peercert = tls_out.peercert;
1631 addr->peerdn = tls_out.peerdn;
1632 addr->ocsp = tls_out.ocsp;
1637 /* if smtps, we'll have smtp_command set to something else; always safe to
1639 smtp_command = big_buffer;
1641 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1642 helo_data is null, we are dealing with a connection that was passed from
1643 another process, and so we won't have expanded helo_data above. We have to
1644 expand it here. $sending_ip_address and $sending_port are set up right at the
1645 start of the Exim process (in exim.c). */
1647 if (tls_out.active >= 0)
1650 if (helo_data == NULL)
1652 helo_data = expand_string(ob->helo_data);
1653 if (helo_data == NULL)
1655 uschar *message = string_sprintf("failed to expand helo_data: %s",
1656 expand_string_message);
1657 set_errno(addrlist, 0, message, DEFER, FALSE, NULL);
1663 /* For SMTPS we need to wait for the initial OK response. */
1666 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1667 ob->command_timeout)) goto RESPONSE_FAILED;
1671 greeting_cmd = "EHLO";
1674 greeting_cmd = "HELO";
1676 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1679 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1680 lmtp? "LHLO" : greeting_cmd, helo_data) < 0)
1682 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1683 ob->command_timeout))
1684 goto RESPONSE_FAILED;
1687 /* If the host is required to use a secure channel, ensure that we
1691 # ifdef EXPERIMENTAL_DANE
1694 verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
1695 host->address, NULL) == OK
1698 save_errno = ERRNO_TLSREQUIRED;
1699 message = string_sprintf("a TLS session is required, but %s",
1700 tls_offered? "an attempt to start TLS failed" :
1701 "the server did not offer TLS support");
1704 #endif /*SUPPORT_TLS*/
1706 /* If TLS is active, we have just started it up and re-done the EHLO command,
1707 so its response needs to be analyzed. If TLS is not active and this is a
1708 continued session down a previously-used socket, we haven't just done EHLO, so
1711 if (continue_hostname == NULL
1713 || tls_out.active >= 0
1717 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
1718 lmtp_ignore_quota option was set. */
1720 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1721 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1722 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1724 /* If the response to EHLO specified support for the SIZE parameter, note
1725 this, provided size_addition is non-negative. */
1727 smtp_use_size = esmtp && ob->size_addition >= 0 &&
1728 pcre_exec(regex_SIZE, NULL, CS buffer, Ustrlen(CS buffer), 0,
1729 PCRE_EOPT, NULL, 0) >= 0;
1731 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
1732 the current host, esmtp will be false, so PIPELINING can never be used. If
1733 the current host matches hosts_avoid_pipelining, don't do it. */
1735 smtp_use_pipelining = esmtp &&
1736 verify_check_this_host(&(ob->hosts_avoid_pipelining), NULL, host->name,
1737 host->address, NULL) != OK &&
1738 pcre_exec(regex_PIPELINING, NULL, CS buffer, Ustrlen(CS buffer), 0,
1739 PCRE_EOPT, NULL, 0) >= 0;
1741 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
1742 smtp_use_pipelining? "" : "not ");
1744 #ifndef DISABLE_PRDR
1745 prdr_offered = esmtp &&
1746 pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(CS buffer), 0,
1747 PCRE_EOPT, NULL, 0) >= 0 &&
1748 verify_check_this_host(&(ob->hosts_try_prdr), NULL, host->name,
1749 host->address, NULL) == OK;
1752 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1755 #ifdef EXPERIMENTAL_DSN
1756 /* Note if the server supports DSN */
1757 smtp_use_dsn = esmtp && pcre_exec(regex_DSN, NULL, CS buffer, (int)Ustrlen(CS buffer), 0,
1758 PCRE_EOPT, NULL, 0) >= 0;
1759 DEBUG(D_transport) debug_printf("use_dsn=%d\n", smtp_use_dsn);
1762 /* Note if the response to EHLO specifies support for the AUTH extension.
1763 If it has, check that this host is one we want to authenticate to, and do
1764 the business. The host name and address must be available when the
1765 authenticator's client driver is running. */
1767 switch (yield = smtp_auth(buffer, sizeof(buffer), addrlist, host,
1768 ob, esmtp, &inblock, &outblock))
1770 default: goto SEND_QUIT;
1772 case FAIL_SEND: goto SEND_FAILED;
1773 case FAIL: goto RESPONSE_FAILED;
1777 /* The setting up of the SMTP call is now complete. Any subsequent errors are
1778 message-specific. */
1782 /* If there is a filter command specified for this transport, we can now
1783 set it up. This cannot be done until the identify of the host is known. */
1785 if (tblock->filter_command != NULL)
1789 sprintf(CS buffer, "%.50s transport", tblock->name);
1790 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
1791 TRUE, DEFER, addrlist, buffer, NULL);
1792 transport_filter_timeout = tblock->filter_timeout;
1794 /* On failure, copy the error to all addresses, abandon the SMTP call, and
1799 set_errno(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
1807 /* For messages that have more than the maximum number of envelope recipients,
1808 we want to send several transactions down the same SMTP connection. (See
1809 comments in deliver.c as to how this reconciles, heuristically, with
1810 remote_max_parallel.) This optimization was added to Exim after the following
1811 code was already working. The simplest way to put it in without disturbing the
1812 code was to use a goto to jump back to this point when there is another
1813 transaction to handle. */
1816 sync_addr = first_addr;
1820 completed_address = FALSE;
1823 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
1824 qualification, send it, adding something to the message size to allow for
1825 imprecision and things that get added en route. Exim keeps the number of lines
1826 in a message, so we can give an accurate value for the original message, but we
1827 need some additional to handle added headers. (Double "." characters don't get
1828 included in the count.) */
1835 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
1839 #ifndef DISABLE_PRDR
1840 prdr_active = FALSE;
1843 for (addr = first_addr; addr; addr = addr->next)
1844 if (addr->transport_return == PENDING_DEFER)
1846 for (addr = addr->next; addr; addr = addr->next)
1847 if (addr->transport_return == PENDING_DEFER)
1848 { /* at least two recipients to send */
1850 sprintf(CS p, " PRDR"); p += 5;
1858 #ifdef EXPERIMENTAL_DSN
1859 /* check if all addresses have lasthop flag */
1860 /* do not send RET and ENVID if true */
1861 dsn_all_lasthop = TRUE;
1862 for (addr = first_addr;
1863 address_count < max_rcpt && addr != NULL;
1865 if ((addr->dsn_flags & rf_dsnlasthop) != 1)
1866 dsn_all_lasthop = FALSE;
1868 /* Add any DSN flags to the mail command */
1870 if ((smtp_use_dsn) && (dsn_all_lasthop == FALSE))
1872 if (dsn_ret == dsn_ret_hdrs)
1874 strcpy(p, " RET=HDRS");
1877 else if (dsn_ret == dsn_ret_full)
1879 strcpy(p, " RET=FULL");
1882 if (dsn_envid != NULL)
1884 string_format(p, sizeof(buffer) - (p-buffer), " ENVID=%s", dsn_envid);
1890 /* If an authenticated_sender override has been specified for this transport
1891 instance, expand it. If the expansion is forced to fail, and there was already
1892 an authenticated_sender for this message, the original value will be used.
1893 Other expansion failures are serious. An empty result is ignored, but there is
1894 otherwise no check - this feature is expected to be used with LMTP and other
1895 cases where non-standard addresses (e.g. without domains) might be required. */
1897 if (smtp_mail_auth_str(p, sizeof(buffer) - (p-buffer), addrlist, ob))
1903 /* From here until we send the DATA command, we can make use of PIPELINING
1904 if the server host supports it. The code has to be able to check the responses
1905 at any point, for when the buffer fills up, so we write it totally generally.
1906 When PIPELINING is off, each command written reports that it has flushed the
1909 pending_MAIL = TRUE; /* The block starts with MAIL */
1911 rc = smtp_write_command(&outblock, smtp_use_pipelining,
1912 "MAIL FROM:<%s>%s\r\n", return_path, buffer);
1913 mail_command = string_copy(big_buffer); /* Save for later error message */
1917 case -1: /* Transmission error */
1920 case +1: /* Block was sent */
1921 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1922 ob->command_timeout))
1924 if (errno == 0 && buffer[0] == '4')
1926 errno = ERRNO_MAIL4XX;
1927 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1929 goto RESPONSE_FAILED;
1931 pending_MAIL = FALSE;
1935 /* Pass over all the relevant recipient addresses for this host, which are the
1936 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
1937 several before we have to read the responses for those seen so far. This
1938 checking is done by a subroutine because it also needs to be done at the end.
1939 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
1940 the next one if not all are sent.
1942 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
1943 last address because we want to abort if any recipients have any kind of
1944 problem, temporary or permanent. We know that all recipient addresses will have
1945 the PENDING_DEFER status, because only one attempt is ever made, and we know
1946 that max_rcpt will be large, so all addresses will be done at once. */
1948 for (addr = first_addr;
1949 address_count < max_rcpt && addr != NULL;
1955 #ifdef EXPERIMENTAL_DSN
1956 addr->dsn_aware = smtp_use_dsn ? dsn_support_yes : dsn_support_no;
1959 if (addr->transport_return != PENDING_DEFER) continue;
1962 no_flush = smtp_use_pipelining && (!mua_wrapper || addr->next != NULL);
1964 #ifdef EXPERIMENTAL_DSN
1965 /* Add any DSN flags to the rcpt command and add to the sent string */
1970 if (smtp_use_dsn && (addr->dsn_flags & rf_dsnlasthop) != 1)
1972 if ((addr->dsn_flags & rf_dsnflags) != 0)
1976 strcpy(p, " NOTIFY=");
1978 for (i = 0; i < 4; i++)
1979 if ((addr->dsn_flags & rf_list[i]) != 0)
1981 if (!first) *p++ = ',';
1983 strcpy(p, rf_names[i]);
1988 if (addr->dsn_orcpt != NULL)
1990 string_format(p, sizeof(buffer) - (p-buffer), " ORCPT=%s",
1998 /* Now send the RCPT command, and process outstanding responses when
1999 necessary. After a timeout on RCPT, we just end the function, leaving the
2000 yield as OK, because this error can often mean that there is a problem with
2001 just one address, so we don't want to delay the host. */
2003 #ifdef EXPERIMENTAL_DSN
2004 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s%s\r\n",
2005 transport_rcpt_address(addr, tblock->rcpt_include_affixes), igquotstr, buffer);
2007 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s\r\n",
2008 transport_rcpt_address(addr, tblock->rcpt_include_affixes), igquotstr);
2011 if (count < 0) goto SEND_FAILED;
2014 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
2015 &sync_addr, host, count, ob->address_retry_include_sender,
2016 pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
2019 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2020 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2023 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2024 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2025 case 0: /* No 2xx or 5xx, but no probs */
2028 case -1: goto END_OFF; /* Timeout on RCPT */
2029 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
2031 pending_MAIL = FALSE; /* Dealt with MAIL */
2033 } /* Loop for next address */
2035 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
2036 permanently or temporarily. We should have flushed and synced after the last
2041 address_item *badaddr;
2042 for (badaddr = first_addr; badaddr != NULL; badaddr = badaddr->next)
2044 if (badaddr->transport_return != PENDING_OK) break;
2046 if (badaddr != NULL)
2048 set_errno(addrlist, 0, badaddr->message, FAIL,
2049 testflag(badaddr, af_pass_message), NULL);
2054 /* If ok is TRUE, we know we have got at least one good recipient, and must now
2055 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
2056 have a good recipient buffered up if we are pipelining. We don't want to waste
2057 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
2058 are pipelining. The responses are all handled by sync_responses(). */
2060 if (ok || (smtp_use_pipelining && !mua_wrapper))
2062 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
2063 if (count < 0) goto SEND_FAILED;
2064 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
2065 host, count, ob->address_retry_include_sender, pending_MAIL,
2066 ok? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
2068 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2069 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2072 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2073 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2074 case 0: break; /* No 2xx or 5xx, but no probs */
2076 case -1: goto END_OFF; /* Timeout on RCPT */
2077 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2081 /* Save the first address of the next batch. */
2085 /* If there were no good recipients (but otherwise there have been no
2086 problems), just set ok TRUE, since we have handled address-specific errors
2087 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
2088 for handling the SMTP dot-handling protocol, flagging to apply to headers as
2089 well as body. Set the appropriate timeout value to be used for each chunk.
2090 (Haven't been able to make it work using select() for writing yet.) */
2092 if (!ok) ok = TRUE; else
2094 sigalrm_seen = FALSE;
2095 transport_write_timeout = ob->data_timeout;
2096 smtp_command = US"sending data block"; /* For error messages */
2097 DEBUG(D_transport|D_v)
2098 debug_printf(" SMTP>> writing message and terminating \".\"\n");
2099 transport_count = 0;
2101 #ifndef DISABLE_DKIM
2102 ok = dkim_transport_write_message(addrlist, inblock.sock,
2103 topt_use_crlf | topt_end_dot | topt_escape_headers |
2104 (tblock->body_only? topt_no_headers : 0) |
2105 (tblock->headers_only? topt_no_body : 0) |
2106 (tblock->return_path_add? topt_add_return_path : 0) |
2107 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
2108 (tblock->envelope_to_add? topt_add_envelope_to : 0),
2109 0, /* No size limit */
2110 tblock->add_headers, tblock->remove_headers,
2111 US".", US"..", /* Escaping strings */
2112 tblock->rewrite_rules, tblock->rewrite_existflags,
2113 ob->dkim_private_key, ob->dkim_domain, ob->dkim_selector,
2114 ob->dkim_canon, ob->dkim_strict, ob->dkim_sign_headers
2117 ok = transport_write_message(addrlist, inblock.sock,
2118 topt_use_crlf | topt_end_dot | topt_escape_headers |
2119 (tblock->body_only? topt_no_headers : 0) |
2120 (tblock->headers_only? topt_no_body : 0) |
2121 (tblock->return_path_add? topt_add_return_path : 0) |
2122 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
2123 (tblock->envelope_to_add? topt_add_envelope_to : 0),
2124 0, /* No size limit */
2125 tblock->add_headers, tblock->remove_headers,
2126 US".", US"..", /* Escaping strings */
2127 tblock->rewrite_rules, tblock->rewrite_existflags);
2130 /* transport_write_message() uses write() because it is called from other
2131 places to write to non-sockets. This means that under some OS (e.g. Solaris)
2132 it can exit with "Broken pipe" as its error. This really means that the
2133 socket got closed at the far end. */
2135 transport_write_timeout = 0; /* for subsequent transports */
2137 /* Failure can either be some kind of I/O disaster (including timeout),
2138 or the failure of a transport filter or the expansion of added headers. */
2142 buffer[0] = 0; /* There hasn't been a response */
2143 goto RESPONSE_FAILED;
2146 /* We used to send the terminating "." explicitly here, but because of
2147 buffering effects at both ends of TCP/IP connections, you don't gain
2148 anything by keeping it separate, so it might as well go in the final
2149 data buffer for efficiency. This is now done by setting the topt_end_dot
2152 smtp_command = US"end of data";
2154 #ifndef DISABLE_PRDR
2155 /* For PRDR we optionally get a partial-responses warning
2156 * followed by the individual responses, before going on with
2157 * the overall response. If we don't get the warning then deal
2158 * with per non-PRDR. */
2161 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '3',
2163 if (!ok && errno == 0)
2166 case '2': prdr_active = FALSE;
2169 case '4': errno = ERRNO_DATA4XX;
2170 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2177 /* For non-PRDR SMTP, we now read a single response that applies to the
2178 whole message. If it is OK, then all the addresses have been delivered. */
2182 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2184 if (!ok && errno == 0 && buffer[0] == '4')
2186 errno = ERRNO_DATA4XX;
2187 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2191 /* For LMTP, we get back a response for every RCPT command that we sent;
2192 some may be accepted and some rejected. For those that get a response, their
2193 status is fixed; any that are accepted have been handed over, even if later
2194 responses crash - at least, that's how I read RFC 2033.
2196 If all went well, mark the recipient addresses as completed, record which
2197 host/IPaddress they were delivered to, and cut out RSET when sending another
2198 message down the same channel. Write the completed addresses to the journal
2199 now so that they are recorded in case there is a crash of hardware or
2200 software before the spool gets updated. Also record the final SMTP
2201 confirmation if needed (for SMTP only). */
2206 int delivery_time = (int)(time(NULL) - start_delivery_time);
2209 uschar *conf = NULL;
2212 /* Make a copy of the host if it is local to this invocation
2213 of the transport. */
2217 thost = store_get(sizeof(host_item));
2219 thost->name = string_copy(host->name);
2220 thost->address = string_copy(host->address);
2224 /* Set up confirmation if needed - applies only to SMTP */
2227 #ifndef EXPERIMENTAL_EVENT
2228 (log_extra_selector & LX_smtp_confirmation) != 0 &&
2233 uschar *s = string_printing(buffer);
2234 conf = (s == buffer)? (uschar *)string_copy(s) : s;
2237 /* Process all transported addresses - for LMTP or PRDR, read a status for
2240 for (addr = addrlist; addr != first_addr; addr = addr->next)
2242 if (addr->transport_return != PENDING_OK) continue;
2244 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
2245 remaining addresses. Otherwise, it's a return code for just the one
2246 address. For temporary errors, add a retry item for the address so that
2247 it doesn't get tried again too soon. */
2249 #ifndef DISABLE_PRDR
2250 if (lmtp || prdr_active)
2255 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2258 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
2259 addr->message = string_sprintf(
2260 #ifndef DISABLE_PRDR
2261 "%s error after %s: %s", prdr_active ? "PRDR":"LMTP",
2263 "LMTP error after %s: %s",
2265 big_buffer, string_printing(buffer));
2266 setflag(addr, af_pass_message); /* Allow message to go to user */
2267 if (buffer[0] == '5')
2268 addr->transport_return = FAIL;
2271 errno = ERRNO_DATA4XX;
2272 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2273 addr->transport_return = DEFER;
2274 #ifndef DISABLE_PRDR
2277 retry_add_item(addr, addr->address_retry_key, 0);
2281 completed_address = TRUE; /* NOW we can set this flag */
2282 if ((log_extra_selector & LX_smtp_confirmation) != 0)
2284 uschar *s = string_printing(buffer);
2285 conf = (s == buffer)? (uschar *)string_copy(s) : s;
2289 /* SMTP, or success return from LMTP for this address. Pass back the
2290 actual host that was used. */
2292 addr->transport_return = OK;
2293 addr->more_errno = delivery_time;
2294 addr->host_used = thost;
2295 addr->special_action = flag;
2296 addr->message = conf;
2297 #ifndef DISABLE_PRDR
2298 if (prdr_active) addr->flags |= af_prdr_used;
2302 #ifndef DISABLE_PRDR
2306 /* Update the journal. For homonymic addresses, use the base address plus
2307 the transport name. See lots of comments in deliver.c about the reasons
2308 for the complications when homonyms are involved. Just carry on after
2309 write error, as it may prove possible to update the spool file later. */
2311 if (testflag(addr, af_homonym))
2312 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2314 sprintf(CS buffer, "%.500s\n", addr->unique);
2316 DEBUG(D_deliver) debug_printf("journalling %s", buffer);
2317 len = Ustrlen(CS buffer);
2318 if (write(journal_fd, buffer, len) != len)
2319 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2320 "%s: %s", buffer, strerror(errno));
2324 #ifndef DISABLE_PRDR
2327 /* PRDR - get the final, overall response. For any non-success
2328 upgrade all the address statuses. */
2329 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2333 if(errno == 0 && buffer[0] == '4')
2335 errno = ERRNO_DATA4XX;
2336 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2338 for (addr = addrlist; addr != first_addr; addr = addr->next)
2339 if (buffer[0] == '5' || addr->transport_return == OK)
2340 addr->transport_return = PENDING_OK; /* allow set_errno action */
2341 goto RESPONSE_FAILED;
2344 /* Update the journal, or setup retry. */
2345 for (addr = addrlist; addr != first_addr; addr = addr->next)
2346 if (addr->transport_return == OK)
2348 if (testflag(addr, af_homonym))
2349 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2351 sprintf(CS buffer, "%.500s\n", addr->unique);
2353 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s", buffer);
2354 len = Ustrlen(CS buffer);
2355 if (write(journal_fd, buffer, len) != len)
2356 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2357 "%s: %s", buffer, strerror(errno));
2359 else if (addr->transport_return == DEFER)
2360 retry_add_item(addr, addr->address_retry_key, -2);
2364 /* Ensure the journal file is pushed out to disk. */
2366 if (EXIMfsync(journal_fd) < 0)
2367 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
2373 /* Handle general (not specific to one address) failures here. The value of ok
2374 is used to skip over this code on the falling through case. A timeout causes a
2375 deferral. Other errors may defer or fail according to the response code, and
2376 may set up a special errno value, e.g. after connection chopped, which is
2377 assumed if errno == 0 and there is no text in the buffer. If control reaches
2378 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
2379 the problem is not related to this specific message. */
2388 send_quit = check_response(host, &save_errno, addrlist->more_errno,
2389 buffer, &code, &message, &pass_message);
2395 message = US string_sprintf("send() to %s [%s] failed: %s",
2396 host->name, host->address, strerror(save_errno));
2400 /* This label is jumped to directly when a TLS negotiation has failed,
2401 or was not done for a host for which it is required. Values will be set
2402 in message and save_errno, and setting_up will always be true. Treat as
2403 a temporary error. */
2410 /* If the failure happened while setting up the call, see if the failure was
2411 a 5xx response (this will either be on connection, or following HELO - a 5xx
2412 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
2413 never going to accept them. For other errors during setting up (timeouts or
2414 whatever), defer all addresses, and yield DEFER, so that the host is not
2415 tried again for a while. */
2418 ok = FALSE; /* For when reached by GOTO */
2423 set_errno(addrlist, save_errno, message, FAIL, pass_message, host);
2426 set_errno(addrlist, save_errno, message, DEFER, pass_message, host);
2431 /* We want to handle timeouts after MAIL or "." and loss of connection after
2432 "." specially. They can indicate a problem with the sender address or with
2433 the contents of the message rather than a real error on the connection. These
2434 cases are treated in the same way as a 4xx response. This next bit of code
2435 does the classification. */
2446 message_error = TRUE;
2450 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
2451 Ustrncmp(smtp_command,"end ",4) == 0;
2454 case ERRNO_SMTPCLOSED:
2455 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
2459 message_error = FALSE;
2463 /* Handle the cases that are treated as message errors. These are:
2465 (a) negative response or timeout after MAIL
2466 (b) negative response after DATA
2467 (c) negative response or timeout or dropped connection after "."
2469 It won't be a negative response or timeout after RCPT, as that is dealt
2470 with separately above. The action in all cases is to set an appropriate
2471 error code for all the addresses, but to leave yield set to OK because the
2472 host itself has not failed. Of course, it might in practice have failed
2473 when we've had a timeout, but if so, we'll discover that at the next
2474 delivery attempt. For a temporary error, set the message_defer flag, and
2475 write to the logs for information if this is not the last host. The error
2476 for the last host will be logged as part of the address's log line. */
2480 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
2481 set_errno(addrlist, save_errno, message, (code == '5')? FAIL : DEFER,
2482 pass_message, host);
2484 /* If there's an errno, the message contains just the identity of
2487 if (code != '5') /* Anything other than 5 is treated as temporary */
2490 message = US string_sprintf("%s: %s", message, strerror(save_errno));
2491 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
2492 msglog_line(host, message);
2493 *message_defer = TRUE;
2497 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
2498 ".", or some other transportation error. We defer all addresses and yield
2499 DEFER, except for the case of failed add_headers expansion, or a transport
2500 filter failure, when the yield should be ERROR, to stop it trying other
2505 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
2506 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
2507 set_errno(addrlist, save_errno, message, DEFER, pass_message, host);
2513 /* If all has gone well, send_quit will be set TRUE, implying we can end the
2514 SMTP session tidily. However, if there were too many addresses to send in one
2515 message (indicated by first_addr being non-NULL) we want to carry on with the
2516 rest of them. Also, it is desirable to send more than one message down the SMTP
2517 connection if there are several waiting, provided we haven't already sent so
2518 many as to hit the configured limit. The function transport_check_waiting looks
2519 for a waiting message and returns its id. Then transport_pass_socket tries to
2520 set up a continued delivery by passing the socket on to another process. The
2521 variable send_rset is FALSE if a message has just been successfully transfered.
2523 If we are already sending down a continued channel, there may be further
2524 addresses not yet delivered that are aimed at the same host, but which have not
2525 been passed in this run of the transport. In this case, continue_more will be
2526 true, and all we should do is send RSET if necessary, and return, leaving the
2529 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
2530 do not want to continue with other messages down the same channel, because that
2531 can lead to looping between two or more messages, all with the same,
2532 temporarily failing address(es). [The retry information isn't updated yet, so
2533 new processes keep on trying.] We probably also don't want to try more of this
2534 message's addresses either.
2536 If we have started a TLS session, we have to end it before passing the
2537 connection to a new process. However, not all servers can handle this (Exim
2538 can), so we do not pass such a connection on if the host matches
2539 hosts_nopass_tls. */
2542 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
2543 "yield=%d first_address is %sNULL\n", ok, send_quit, send_rset,
2544 continue_more, yield, (first_addr == NULL)? "":"not ");
2546 if (completed_address && ok && send_quit)
2549 if (first_addr != NULL || continue_more ||
2551 (tls_out.active < 0 ||
2552 verify_check_this_host(&(ob->hosts_nopass_tls), NULL, host->name,
2553 host->address, NULL) != OK)
2555 transport_check_waiting(tblock->name, host->name,
2556 tblock->connection_max_messages, new_message_id, &more)
2564 if (! (ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
2566 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
2567 host->address, strerror(save_errno));
2570 else if (! (ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2571 ob->command_timeout)))
2574 send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
2578 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
2579 host->name, host->address, msg);
2584 /* Either RSET was not needed, or it succeeded */
2588 if (first_addr != NULL) /* More addresses still to be sent */
2589 { /* in this run of the transport */
2590 continue_sequence++; /* Causes * in logging */
2593 if (continue_more) return yield; /* More addresses for another run */
2595 /* Pass the socket to a new Exim process. Before doing so, we must shut
2596 down TLS. Not all MTAs allow for the continuation of the SMTP session
2597 when TLS is shut down. We test for this by sending a new EHLO. If we
2598 don't get a good response, we don't attempt to pass the socket on. */
2601 if (tls_out.active >= 0)
2603 tls_close(FALSE, TRUE);
2607 ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
2608 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2609 ob->command_timeout);
2613 /* If the socket is successfully passed, we musn't send QUIT (or
2614 indeed anything!) from here. */
2616 if (ok && transport_pass_socket(tblock->name, host->name, host->address,
2617 new_message_id, inblock.sock))
2623 /* If RSET failed and there are addresses left, they get deferred. */
2625 else set_errno(first_addr, errno, msg, DEFER, FALSE, host);
2629 /* End off tidily with QUIT unless the connection has died or the socket has
2630 been passed to another process. There has been discussion on the net about what
2631 to do after sending QUIT. The wording of the RFC suggests that it is necessary
2632 to wait for a response, but on the other hand, there isn't anything one can do
2633 with an error response, other than log it. Exim used to do that. However,
2634 further discussion suggested that it is positively advantageous not to wait for
2635 the response, but to close the session immediately. This is supposed to move
2636 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
2637 load from the server. (Hosts that are both servers and clients may not see much
2638 difference, of course.) Further discussion indicated that this was safe to do
2639 on Unix systems which have decent implementations of TCP/IP that leave the
2640 connection around for a while (TIME_WAIT) after the application has gone away.
2641 This enables the response sent by the server to be properly ACKed rather than
2642 timed out, as can happen on broken TCP/IP implementations on other OS.
2644 This change is being made on 31-Jul-98. After over a year of trouble-free
2645 operation, the old commented-out code was removed on 17-Sep-99. */
2648 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2653 tls_close(FALSE, TRUE);
2656 /* Close the socket, and return the appropriate value, first setting
2657 works because the NULL setting is passed back to the calling process, and
2658 remote_max_parallel is forced to 1 when delivering over an existing connection,
2660 If all went well and continue_more is set, we shouldn't actually get here if
2661 there are further addresses, as the return above will be taken. However,
2662 writing RSET might have failed, or there may be other addresses whose hosts are
2663 specified in the transports, and therefore not visible at top level, in which
2664 case continue_more won't get set. */
2666 (void)close(inblock.sock);
2668 #ifdef EXPERIMENTAL_EVENT
2669 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
2672 continue_transport = NULL;
2673 continue_hostname = NULL;
2680 /*************************************************
2681 * Closedown entry point *
2682 *************************************************/
2684 /* This function is called when exim is passed an open smtp channel
2685 from another incarnation, but the message which it has been asked
2686 to deliver no longer exists. The channel is on stdin.
2688 We might do fancy things like looking for another message to send down
2689 the channel, but if the one we sought has gone, it has probably been
2690 delivered by some other process that itself will seek further messages,
2691 so just close down our connection.
2693 Argument: pointer to the transport instance block
2698 smtp_transport_closedown(transport_instance *tblock)
2700 smtp_transport_options_block *ob =
2701 (smtp_transport_options_block *)(tblock->options_block);
2702 smtp_inblock inblock;
2703 smtp_outblock outblock;
2705 uschar inbuffer[4096];
2706 uschar outbuffer[16];
2708 inblock.sock = fileno(stdin);
2709 inblock.buffer = inbuffer;
2710 inblock.buffersize = sizeof(inbuffer);
2711 inblock.ptr = inbuffer;
2712 inblock.ptrend = inbuffer;
2714 outblock.sock = inblock.sock;
2715 outblock.buffersize = sizeof(outbuffer);
2716 outblock.buffer = outbuffer;
2717 outblock.ptr = outbuffer;
2718 outblock.cmd_count = 0;
2719 outblock.authenticating = FALSE;
2721 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2722 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2723 ob->command_timeout);
2724 (void)close(inblock.sock);
2729 /*************************************************
2730 * Prepare addresses for delivery *
2731 *************************************************/
2733 /* This function is called to flush out error settings from previous delivery
2734 attempts to other hosts. It also records whether we got here via an MX record
2735 or not in the more_errno field of the address. We are interested only in
2736 addresses that are still marked DEFER - others may have got delivered to a
2737 previously considered IP address. Set their status to PENDING_DEFER to indicate
2738 which ones are relevant this time.
2741 addrlist the list of addresses
2742 host the host we are delivering to
2744 Returns: the first address for this delivery
2747 static address_item *
2748 prepare_addresses(address_item *addrlist, host_item *host)
2750 address_item *first_addr = NULL;
2752 for (addr = addrlist; addr != NULL; addr = addr->next)
2754 if (addr->transport_return != DEFER) continue;
2755 if (first_addr == NULL) first_addr = addr;
2756 addr->transport_return = PENDING_DEFER;
2757 addr->basic_errno = 0;
2758 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
2759 addr->message = NULL;
2761 addr->cipher = NULL;
2762 addr->ourcert = NULL;
2763 addr->peercert = NULL;
2764 addr->peerdn = NULL;
2765 addr->ocsp = OCSP_NOT_REQ;
2773 /*************************************************
2774 * Main entry point *
2775 *************************************************/
2777 /* See local README for interface details. As this is a remote transport, it is
2778 given a chain of addresses to be delivered in one connection, if possible. It
2779 always returns TRUE, indicating that each address has its own independent
2780 status set, except if there is a setting up problem, in which case it returns
2784 smtp_transport_entry(
2785 transport_instance *tblock, /* data for this instantiation */
2786 address_item *addrlist) /* addresses we are working on */
2790 int hosts_defer = 0;
2792 int hosts_looked_up = 0;
2793 int hosts_retry = 0;
2794 int hosts_serial = 0;
2795 int hosts_total = 0;
2796 int total_hosts_tried = 0;
2798 BOOL expired = TRUE;
2799 BOOL continuing = continue_hostname != NULL;
2800 uschar *expanded_hosts = NULL;
2802 uschar *tid = string_sprintf("%s transport", tblock->name);
2803 smtp_transport_options_block *ob =
2804 (smtp_transport_options_block *)(tblock->options_block);
2805 host_item *hostlist = addrlist->host_list;
2806 host_item *host = NULL;
2810 debug_printf("%s transport entered\n", tblock->name);
2811 for (addr = addrlist; addr != NULL; addr = addr->next)
2812 debug_printf(" %s\n", addr->address);
2813 if (continuing) debug_printf("already connected to %s [%s]\n",
2814 continue_hostname, continue_host_address);
2817 /* Set the flag requesting that these hosts be added to the waiting
2818 database if the delivery fails temporarily or if we are running with
2819 queue_smtp or a 2-stage queue run. This gets unset for certain
2820 kinds of error, typically those that are specific to the message. */
2822 update_waiting = TRUE;
2824 /* If a host list is not defined for the addresses - they must all have the
2825 same one in order to be passed to a single transport - or if the transport has
2826 a host list with hosts_override set, use the host list supplied with the
2827 transport. It is an error for this not to exist. */
2829 if (hostlist == NULL || (ob->hosts_override && ob->hosts != NULL))
2831 if (ob->hosts == NULL)
2833 addrlist->message = string_sprintf("%s transport called with no hosts set",
2835 addrlist->transport_return = PANIC;
2836 return FALSE; /* Only top address has status */
2839 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
2842 /* If the transport's host list contains no '$' characters, and we are not
2843 randomizing, it is fixed and therefore a chain of hosts can be built once
2844 and for all, and remembered for subsequent use by other calls to this
2845 transport. If, on the other hand, the host list does contain '$', or we are
2846 randomizing its order, we have to rebuild it each time. In the fixed case,
2847 as the hosts string will never be used again, it doesn't matter that we
2848 replace all the : characters with zeros. */
2850 if (ob->hostlist == NULL)
2852 uschar *s = ob->hosts;
2854 if (Ustrchr(s, '$') != NULL)
2856 expanded_hosts = expand_string(s);
2857 if (expanded_hosts == NULL)
2859 addrlist->message = string_sprintf("failed to expand list of hosts "
2860 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
2861 addrlist->transport_return = search_find_defer? DEFER : PANIC;
2862 return FALSE; /* Only top address has status */
2864 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
2865 "\"%s\"\n", s, expanded_hosts);
2869 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
2871 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
2873 /* Check that the expansion yielded something useful. */
2874 if (hostlist == NULL)
2877 string_sprintf("%s transport has empty hosts setting", tblock->name);
2878 addrlist->transport_return = PANIC;
2879 return FALSE; /* Only top address has status */
2882 /* If there was no expansion of hosts, save the host list for
2885 if (expanded_hosts == NULL) ob->hostlist = hostlist;
2888 /* This is not the first time this transport has been run in this delivery;
2889 the host list was built previously. */
2891 else hostlist = ob->hostlist;
2894 /* The host list was supplied with the address. If hosts_randomize is set, we
2895 must sort it into a random order if it did not come from MX records and has not
2896 already been randomized (but don't bother if continuing down an existing
2899 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continuing)
2901 host_item *newlist = NULL;
2902 while (hostlist != NULL)
2904 host_item *h = hostlist;
2905 hostlist = hostlist->next;
2907 h->sort_key = random_number(100);
2909 if (newlist == NULL)
2914 else if (h->sort_key < newlist->sort_key)
2921 host_item *hh = newlist;
2922 while (hh->next != NULL)
2924 if (h->sort_key < hh->next->sort_key) break;
2932 hostlist = addrlist->host_list = newlist;
2936 /* Sort out the default port. */
2938 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
2941 /* For each host-plus-IP-address on the list:
2943 . If this is a continued delivery and the host isn't the one with the
2944 current connection, skip.
2946 . If the status is unusable (i.e. previously failed or retry checked), skip.
2948 . If no IP address set, get the address, either by turning the name into
2949 an address, calling gethostbyname if gethostbyname is on, or by calling
2950 the DNS. The DNS may yield multiple addresses, in which case insert the
2951 extra ones into the list.
2953 . Get the retry data if not previously obtained for this address and set the
2954 field which remembers the state of this address. Skip if the retry time is
2955 not reached. If not, remember whether retry data was found. The retry string
2956 contains both the name and the IP address.
2958 . Scan the list of addresses and mark those whose status is DEFER as
2959 PENDING_DEFER. These are the only ones that will be processed in this cycle
2962 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
2963 Some addresses may be successfully delivered, others may fail, and yet
2964 others may get temporary errors and so get marked DEFER.
2966 . The return from the delivery attempt is OK if a connection was made and a
2967 valid SMTP dialogue was completed. Otherwise it is DEFER.
2969 . If OK, add a "remove" retry item for this host/IPaddress, if any.
2971 . If fail to connect, or other defer state, add a retry item.
2973 . If there are any addresses whose status is still DEFER, carry on to the
2974 next host/IPaddress, unless we have tried the number of hosts given
2975 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
2976 there is some fancy logic for hosts_max_try that means its limit can be
2977 overstepped in some circumstances.
2979 If we get to the end of the list, all hosts have deferred at least one address,
2980 or not reached their retry times. If delay_after_cutoff is unset, it requests a
2981 delivery attempt to those hosts whose last try was before the arrival time of
2982 the current message. To cope with this, we have to go round the loop a second
2983 time. After that, set the status and error data for any addresses that haven't
2984 had it set already. */
2986 for (cutoff_retry = 0; expired &&
2987 cutoff_retry < ((ob->delay_after_cutoff)? 1 : 2);
2990 host_item *nexthost = NULL;
2991 int unexpired_hosts_tried = 0;
2993 for (host = hostlist;
2995 unexpired_hosts_tried < ob->hosts_max_try &&
2996 total_hosts_tried < ob->hosts_max_try_hardlimit;
3002 BOOL serialized = FALSE;
3003 BOOL host_is_expired = FALSE;
3004 BOOL message_defer = FALSE;
3005 BOOL ifchanges = FALSE;
3006 BOOL some_deferred = FALSE;
3007 address_item *first_addr = NULL;
3008 uschar *interface = NULL;
3009 uschar *retry_host_key = NULL;
3010 uschar *retry_message_key = NULL;
3011 uschar *serialize_key = NULL;
3013 /* Default next host is next host. :-) But this can vary if the
3014 hosts_max_try limit is hit (see below). It may also be reset if a host
3015 address is looked up here (in case the host was multihomed). */
3017 nexthost = host->next;
3019 /* If the address hasn't yet been obtained from the host name, look it up
3020 now, unless the host is already marked as unusable. If it is marked as
3021 unusable, it means that the router was unable to find its IP address (in
3022 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
3023 the lookup failed last time. We don't get this far if *all* MX records
3024 point to non-existent hosts; that is treated as a hard error.
3026 We can just skip this host entirely. When the hosts came from the router,
3027 the address will timeout based on the other host(s); when the address is
3028 looked up below, there is an explicit retry record added.
3030 Note that we mustn't skip unusable hosts if the address is not unset; they
3031 may be needed as expired hosts on the 2nd time round the cutoff loop. */
3033 if (host->address == NULL)
3035 int new_port, flags;
3037 uschar *canonical_name;
3039 if (host->status >= hstatus_unusable)
3041 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
3046 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
3048 /* The host name is permitted to have an attached port. Find it, and
3049 strip it from the name. Just remember it for now. */
3051 new_port = host_item_get_port(host);
3053 /* Count hosts looked up */
3057 /* Find by name if so configured, or if it's an IP address. We don't
3058 just copy the IP address, because we need the test-for-local to happen. */
3060 flags = HOST_FIND_BY_A;
3061 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
3062 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
3064 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
3065 rc = host_find_byname(host, NULL, flags, &canonical_name, TRUE);
3067 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
3068 ob->dnssec_request_domains, ob->dnssec_require_domains,
3069 &canonical_name, NULL);
3071 /* Update the host (and any additional blocks, resulting from
3072 multihoming) with a host-specific port, if any. */
3074 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
3076 /* Failure to find the host at this time (usually DNS temporary failure)
3077 is really a kind of routing failure rather than a transport failure.
3078 Therefore we add a retry item of the routing kind, not to stop us trying
3079 to look this name up here again, but to ensure the address gets timed
3080 out if the failures go on long enough. A complete failure at this point
3081 commonly points to a configuration error, but the best action is still
3082 to carry on for the next host. */
3084 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
3086 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
3088 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
3089 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
3090 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
3091 host->status = hstatus_unusable;
3093 for (addr = addrlist; addr != NULL; addr = addr->next)
3095 if (addr->transport_return != DEFER) continue;
3096 addr->basic_errno = ERRNO_UNKNOWNHOST;
3098 string_sprintf("failed to lookup IP address for %s", host->name);
3103 /* If the host is actually the local host, we may have a problem, or
3104 there may be some cunning configuration going on. In the problem case,
3105 log things and give up. The default transport status is already DEFER. */
3107 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
3109 for (addr = addrlist; addr != NULL; addr = addr->next)
3111 addr->basic_errno = 0;
3112 addr->message = string_sprintf("%s transport found host %s to be "
3113 "local", tblock->name, host->name);
3117 } /* End of block for IP address lookup */
3119 /* If this is a continued delivery, we are interested only in the host
3120 which matches the name of the existing open channel. The check is put
3121 here after the local host lookup, in case the name gets expanded as a
3122 result of the lookup. Set expired FALSE, to save the outer loop executing
3125 if (continuing && (Ustrcmp(continue_hostname, host->name) != 0 ||
3126 Ustrcmp(continue_host_address, host->address) != 0))
3129 continue; /* With next host */
3132 /* Reset the default next host in case a multihomed host whose addresses
3133 are not looked up till just above added to the host list. */
3135 nexthost = host->next;
3137 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
3138 domain is in queue_smtp_domains, we don't actually want to attempt any
3139 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
3140 there is a lookup defer in queue_smtp_domains, proceed as if the domain
3141 were not in it. We don't want to hold up all SMTP deliveries! Except when
3142 doing a two-stage queue run, don't do this if forcing. */
3144 if ((!deliver_force || queue_2stage) && (queue_smtp ||
3145 match_isinlist(addrlist->domain, &queue_smtp_domains, 0,
3146 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
3149 for (addr = addrlist; addr != NULL; addr = addr->next)
3151 if (addr->transport_return != DEFER) continue;
3152 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
3154 continue; /* With next host */
3157 /* Count hosts being considered - purely for an intelligent comment
3158 if none are usable. */
3162 /* Set $host and $host address now in case they are needed for the
3163 interface expansion or the serialize_hosts check; they remain set if an
3164 actual delivery happens. */
3166 deliver_host = host->name;
3167 deliver_host_address = host->address;
3168 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
3169 : host->dnssec == DS_NO ? US"no"
3172 /* Set up a string for adding to the retry key if the port number is not
3173 the standard SMTP port. A host may have its own port setting that overrides
3176 pistring = string_sprintf(":%d", (host->port == PORT_NONE)?
3178 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
3180 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
3181 string changes upon expansion, we must add it to the key that is used for
3182 retries, because connections to the same host from a different interface
3183 should be treated separately. */
3185 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET : AF_INET6;
3186 if (!smtp_get_interface(ob->interface, host_af, addrlist, &ifchanges,
3189 if (ifchanges) pistring = string_sprintf("%s/%s", pistring, interface);
3191 /* The first time round the outer loop, check the status of the host by
3192 inspecting the retry data. The second time round, we are interested only
3193 in expired hosts that haven't been tried since this message arrived. */
3195 if (cutoff_retry == 0)
3197 /* Ensure the status of the address is set by checking retry data if
3198 necessary. There maybe host-specific retry data (applicable to all
3199 messages) and also data for retries of a specific message at this host.
3200 If either of these retry records are actually read, the keys used are
3201 returned to save recomputing them later. */
3203 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
3204 ob->retry_include_ip_address, &retry_host_key, &retry_message_key);
3206 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
3207 (host->address == NULL)? US"" : host->address, pistring,
3208 (host->status == hstatus_usable)? "usable" :
3209 (host->status == hstatus_unusable)? "unusable" :
3210 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
3212 /* Skip this address if not usable at this time, noting if it wasn't
3213 actually expired, both locally and in the address. */
3215 switch (host->status)
3217 case hstatus_unusable:
3219 setflag(addrlist, af_retry_skipped);
3222 case hstatus_unusable_expired:
3225 case hwhy_retry: hosts_retry++; break;
3226 case hwhy_failed: hosts_fail++; break;
3227 case hwhy_deferred: hosts_defer++; break;
3230 /* If there was a retry message key, implying that previously there
3231 was a message-specific defer, we don't want to update the list of
3232 messages waiting for these hosts. */
3234 if (retry_message_key != NULL) update_waiting = FALSE;
3235 continue; /* With the next host or IP address */
3239 /* Second time round the loop: if the address is set but expired, and
3240 the message is newer than the last try, let it through. */
3244 if (host->address == NULL ||
3245 host->status != hstatus_unusable_expired ||
3246 host->last_try > received_time)
3249 debug_printf("trying expired host %s [%s]%s\n",
3250 host->name, host->address, pistring);
3251 host_is_expired = TRUE;
3254 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
3255 it remains TRUE only if all hosts are expired and none are actually tried.
3260 /* If this host is listed as one to which access must be serialized,
3261 see if another Exim process has a connection to it, and if so, skip
3262 this host. If not, update the database to record our connection to it
3263 and remember this for later deletion. Do not do any of this if we are
3264 sending the message down a pre-existing connection. */
3267 verify_check_this_host(&(ob->serialize_hosts), NULL, host->name,
3268 host->address, NULL) == OK)
3270 serialize_key = string_sprintf("host-serialize-%s", host->name);
3271 if (!enq_start(serialize_key))
3274 debug_printf("skipping host %s because another Exim process "
3275 "is connected to it\n", host->name);
3282 /* OK, we have an IP address that is not waiting for its retry time to
3283 arrive (it might be expired) OR (second time round the loop) we have an
3284 expired host that hasn't been tried since the message arrived. Have a go
3285 at delivering the message to it. First prepare the addresses by flushing
3286 out the result of previous attempts, and finding the first address that
3287 is still to be delivered. */
3289 first_addr = prepare_addresses(addrlist, host);
3291 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
3292 message_id, host->name, host->address, addrlist->address,
3293 (addrlist->next == NULL)? "" : ", ...");
3295 set_process_info("delivering %s to %s [%s] (%s%s)",
3296 message_id, host->name, host->address, addrlist->address,
3297 (addrlist->next == NULL)? "" : ", ...");
3299 /* This is not for real; don't do the delivery. If there are
3300 any remaining hosts, list them. */
3305 set_errno(addrlist, 0, NULL, OK, FALSE, NULL);
3306 for (addr = addrlist; addr != NULL; addr = addr->next)
3308 addr->host_used = host;
3309 addr->special_action = '*';
3310 addr->message = US"delivery bypassed by -N option";
3314 debug_printf("*** delivery by %s transport bypassed by -N option\n"
3315 "*** host and remaining hosts:\n", tblock->name);
3316 for (host2 = host; host2 != NULL; host2 = host2->next)
3317 debug_printf(" %s [%s]\n", host2->name,
3318 (host2->address == NULL)? US"unset" : host2->address);
3323 /* This is for real. If the host is expired, we don't count it for
3324 hosts_max_retry. This ensures that all hosts must expire before an address
3325 is timed out, unless hosts_max_try_hardlimit (which protects against
3326 lunatic DNS configurations) is reached.
3328 If the host is not expired and we are about to hit the hosts_max_retry
3329 limit, check to see if there is a subsequent hosts with a different MX
3330 value. If so, make that the next host, and don't count this one. This is a
3331 heuristic to make sure that different MXs do get tried. With a normal kind
3332 of retry rule, they would get tried anyway when the earlier hosts were
3333 delayed, but if the domain has a "retry every time" type of rule - as is
3334 often used for the the very large ISPs, that won't happen. */
3338 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
3342 debug_printf("hosts_max_try limit reached with this host\n");
3343 for (h = host; h != NULL; h = h->next)
3344 if (h->mx != host->mx) break;
3348 unexpired_hosts_tried--;
3349 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
3350 "and will be tried\n");
3354 /* Attempt the delivery. */
3356 total_hosts_tried++;
3357 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
3358 expanded_hosts != NULL, &message_defer, FALSE);
3361 OK => connection made, each address contains its result;
3362 message_defer is set for message-specific defers (when all
3363 recipients are marked defer)
3364 DEFER => there was a non-message-specific delivery problem;
3365 ERROR => there was a problem setting up the arguments for a filter,
3366 or there was a problem with expanding added headers
3369 /* If the result is not OK, there was a non-message-specific problem.
3370 If the result is DEFER, we need to write to the logs saying what happened
3371 for this particular host, except in the case of authentication and TLS
3372 failures, where the log has already been written. If all hosts defer a
3373 general message is written at the end. */
3375 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL &&
3376 first_addr->basic_errno != ERRNO_TLSFAILURE)
3377 write_logs(first_addr, host);
3379 #ifdef EXPERIMENTAL_EVENT
3381 deferred_event_raise(first_addr, host);
3384 /* If STARTTLS was accepted, but there was a failure in setting up the
3385 TLS session (usually a certificate screwup), and the host is not in
3386 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
3387 TLS forcibly turned off. We have to start from scratch with a new SMTP
3388 connection. That's why the retry is done from here, not from within
3389 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
3390 session, so the in-clear transmission after those errors, if permitted,
3391 happens inside smtp_deliver().] */
3395 && first_addr->basic_errno == ERRNO_TLSFAILURE
3396 && ob->tls_tempfail_tryclear
3397 && verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
3398 host->address, NULL) != OK
3401 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
3402 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
3403 first_addr = prepare_addresses(addrlist, host);
3404 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
3405 expanded_hosts != NULL, &message_defer, TRUE);
3406 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
3407 write_logs(first_addr, host);
3408 # ifdef EXPERIMENTAL_EVENT
3410 deferred_event_raise(first_addr, host);
3413 #endif /*SUPPORT_TLS*/
3416 /* Delivery attempt finished */
3418 rs = (rc == OK)? US"OK" : (rc == DEFER)? US"DEFER" : (rc == ERROR)?
3421 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
3422 message_id, host->name, host->address, addrlist->address,
3423 (addrlist->next == NULL)? "" : " (& others)", rs);
3425 /* Release serialization if set up */
3427 if (serialized) enq_end(serialize_key);
3429 /* If the result is DEFER, or if a host retry record is known to exist, we
3430 need to add an item to the retry chain for updating the retry database
3431 at the end of delivery. We only need to add the item to the top address,
3432 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
3433 for any other delivery attempts using the same address. (It is copied into
3434 the unusable tree at the outer level, so even if different address blocks
3435 contain the same address, it still won't get tried again.) */
3437 if (rc == DEFER || retry_host_key != NULL)
3439 int delete_flag = (rc != DEFER)? rf_delete : 0;
3440 if (retry_host_key == NULL)
3442 retry_host_key = ob->retry_include_ip_address?
3443 string_sprintf("T:%S:%s%s", host->name, host->address, pistring) :
3444 string_sprintf("T:%S%s", host->name, pistring);
3447 /* If a delivery of another message over an existing SMTP connection
3448 yields DEFER, we do NOT set up retry data for the host. This covers the
3449 case when there are delays in routing the addresses in the second message
3450 that are so long that the server times out. This is alleviated by not
3451 routing addresses that previously had routing defers when handling an
3452 existing connection, but even so, this case may occur (e.g. if a
3453 previously happily routed address starts giving routing defers). If the
3454 host is genuinely down, another non-continued message delivery will
3455 notice it soon enough. */
3457 if (delete_flag != 0 || !continuing)
3458 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
3460 /* We may have tried an expired host, if its retry time has come; ensure
3461 the status reflects the expiry for the benefit of any other addresses. */
3465 host->status = (host_is_expired)?
3466 hstatus_unusable_expired : hstatus_unusable;
3467 host->why = hwhy_deferred;
3471 /* If message_defer is set (host was OK, but every recipient got deferred
3472 because of some message-specific problem), or if that had happened
3473 previously so that a message retry key exists, add an appropriate item
3474 to the retry chain. Note that if there was a message defer but now there is
3475 a host defer, the message defer record gets deleted. That seems perfectly
3476 reasonable. Also, stop the message from being remembered as waiting
3477 for specific hosts. */
3479 if (message_defer || retry_message_key != NULL)
3481 int delete_flag = message_defer? 0 : rf_delete;
3482 if (retry_message_key == NULL)
3484 retry_message_key = ob->retry_include_ip_address?
3485 string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
3487 string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
3489 retry_add_item(addrlist, retry_message_key,
3490 rf_message | rf_host | delete_flag);
3491 update_waiting = FALSE;
3494 /* Any return other than DEFER (that is, OK or ERROR) means that the
3495 addresses have got their final statuses filled in for this host. In the OK
3496 case, see if any of them are deferred. */
3500 for (addr = addrlist; addr != NULL; addr = addr->next)
3502 if (addr->transport_return == DEFER)
3504 some_deferred = TRUE;
3510 /* If no addresses deferred or the result was ERROR, return. We do this for
3511 ERROR because a failing filter set-up or add_headers expansion is likely to
3512 fail for any host we try. */
3514 if (rc == ERROR || (rc == OK && !some_deferred))
3516 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3517 return TRUE; /* Each address has its status */
3520 /* If the result was DEFER or some individual addresses deferred, let
3521 the loop run to try other hosts with the deferred addresses, except for the
3522 case when we were trying to deliver down an existing channel and failed.
3523 Don't try any other hosts in this case. */
3525 if (continuing) break;
3527 /* If the whole delivery, or some individual addresses, were deferred and
3528 there are more hosts that could be tried, do not count this host towards
3529 the hosts_max_try limit if the age of the message is greater than the
3530 maximum retry time for this host. This means we may try try all hosts,
3531 ignoring the limit, when messages have been around for some time. This is
3532 important because if we don't try all hosts, the address will never time
3533 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
3535 if ((rc == DEFER || some_deferred) && nexthost != NULL)
3538 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
3540 if (retry != NULL && retry->rules != NULL)
3542 retry_rule *last_rule;
3543 for (last_rule = retry->rules;
3544 last_rule->next != NULL;
3545 last_rule = last_rule->next);
3546 timedout = time(NULL) - received_time > last_rule->timeout;
3548 else timedout = TRUE; /* No rule => timed out */
3552 unexpired_hosts_tried--;
3553 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
3554 "hosts_max_try (message older than host's retry time)\n");
3557 } /* End of loop for trying multiple hosts. */
3559 /* This is the end of the loop that repeats iff expired is TRUE and
3560 ob->delay_after_cutoff is FALSE. The second time round we will
3561 try those hosts that haven't been tried since the message arrived. */
3565 debug_printf("all IP addresses skipped or deferred at least one address\n");
3566 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
3567 debug_printf("retrying IP addresses not tried since message arrived\n");
3572 /* Get here if all IP addresses are skipped or defer at least one address. In
3573 MUA wrapper mode, this will happen only for connection or other non-message-
3574 specific failures. Force the delivery status for all addresses to FAIL. */
3578 for (addr = addrlist; addr != NULL; addr = addr->next)
3579 addr->transport_return = FAIL;
3583 /* In the normal, non-wrapper case, add a standard message to each deferred
3584 address if there hasn't been an error, that is, if it hasn't actually been
3585 tried this time. The variable "expired" will be FALSE if any deliveries were
3586 actually tried, or if there was at least one host that was not expired. That
3587 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
3588 a delivery has been tried, an error code will be set, and the failing of the
3589 message is handled by the retry code later.
3591 If queue_smtp is set, or this transport was called to send a subsequent message
3592 down an existing TCP/IP connection, and something caused the host not to be
3593 found, we end up here, but can detect these cases and handle them specially. */
3595 for (addr = addrlist; addr != NULL; addr = addr->next)
3597 /* If host is not NULL, it means that we stopped processing the host list
3598 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
3599 means we need to behave as if some hosts were skipped because their retry
3600 time had not come. Specifically, this prevents the address from timing out.
3601 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
3602 hosts were tried. */
3606 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
3609 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
3610 "hosts were tried\n");
3615 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
3616 setflag(addr, af_retry_skipped);
3620 if (queue_smtp) /* no deliveries attempted */
3622 addr->transport_return = DEFER;
3623 addr->basic_errno = 0;
3624 addr->message = US"SMTP delivery explicitly queued";
3627 else if (addr->transport_return == DEFER &&
3628 (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0) &&
3629 addr->message == NULL)
3631 addr->basic_errno = ERRNO_HRETRY;
3632 if (continue_hostname != NULL)
3634 addr->message = US"no host found for existing SMTP connection";
3638 setflag(addr, af_pass_message); /* This is not a security risk */
3639 addr->message = (ob->delay_after_cutoff)?
3640 US"retry time not reached for any host after a long failure period" :
3641 US"all hosts have been failing for a long time and were last tried "
3642 "after this message arrived";
3644 /* If we are already using fallback hosts, or there are no fallback hosts
3645 defined, convert the result to FAIL to cause a bounce. */
3647 if (addr->host_list == addr->fallback_hosts ||
3648 addr->fallback_hosts == NULL)
3649 addr->transport_return = FAIL;
3653 if (hosts_retry == hosts_total)
3654 addr->message = US"retry time not reached for any host";
3655 else if (hosts_fail == hosts_total)
3656 addr->message = US"all host address lookups failed permanently";
3657 else if (hosts_defer == hosts_total)
3658 addr->message = US"all host address lookups failed temporarily";
3659 else if (hosts_serial == hosts_total)
3660 addr->message = US"connection limit reached for all hosts";
3661 else if (hosts_fail+hosts_defer == hosts_total)
3662 addr->message = US"all host address lookups failed";
3663 else addr->message = US"some host address lookups failed and retry time "
3664 "not reached for other hosts or connection limit reached";
3669 /* Update the database which keeps information about which messages are waiting
3670 for which hosts to become available. For some message-specific errors, the
3671 update_waiting flag is turned off because we don't want follow-on deliveries in
3672 those cases. If this transport instance is explicitly limited to one message
3673 per connection then follow-on deliveries are not possible and there's no need
3674 to create/update the per-transport wait-<transport_name> database. */
3676 if (update_waiting && tblock->connection_max_messages != 1)
3677 transport_update_waiting(hostlist, tblock->name);
3681 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3683 return TRUE; /* Each address has its status */
3688 /* End of transport/smtp.c */
git://git.exim.org / exim.git / blob