1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2016 */
6 /* See the file NOTICE for conditions of use and distribution. */
12 #define PENDING_DEFER (PENDING + DEFER)
13 #define PENDING_OK (PENDING + OK)
15 #define DELIVER_BUFFER_SIZE 4096
18 /* Options specific to the smtp transport. This transport also supports LMTP
19 over TCP/IP. The options must be in alphabetic order (note that "_" comes
20 before the lower case letters). Some live in the transport_instance block so as
21 to be publicly visible; these are flagged with opt_public. */
23 optionlist smtp_transport_options[] = {
24 { "*expand_multi_domain", opt_stringptr | opt_hidden | opt_public,
25 (void *)offsetof(transport_instance, expand_multi_domain) },
26 { "*expand_retry_include_ip_address", opt_stringptr | opt_hidden,
27 (void *)(offsetof(smtp_transport_options_block, expand_retry_include_ip_address)) },
29 { "address_retry_include_sender", opt_bool,
30 (void *)offsetof(smtp_transport_options_block, address_retry_include_sender) },
31 { "allow_localhost", opt_bool,
32 (void *)offsetof(smtp_transport_options_block, allow_localhost) },
33 { "authenticated_sender", opt_stringptr,
34 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
35 { "authenticated_sender_force", opt_bool,
36 (void *)offsetof(smtp_transport_options_block, authenticated_sender_force) },
37 { "command_timeout", opt_time,
38 (void *)offsetof(smtp_transport_options_block, command_timeout) },
39 { "connect_timeout", opt_time,
40 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
41 { "connection_max_messages", opt_int | opt_public,
42 (void *)offsetof(transport_instance, connection_max_messages) },
43 { "data_timeout", opt_time,
44 (void *)offsetof(smtp_transport_options_block, data_timeout) },
45 { "delay_after_cutoff", opt_bool,
46 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
48 { "dkim_canon", opt_stringptr,
49 (void *)offsetof(smtp_transport_options_block, dkim.dkim_canon) },
50 { "dkim_domain", opt_stringptr,
51 (void *)offsetof(smtp_transport_options_block, dkim.dkim_domain) },
52 { "dkim_private_key", opt_stringptr,
53 (void *)offsetof(smtp_transport_options_block, dkim.dkim_private_key) },
54 { "dkim_selector", opt_stringptr,
55 (void *)offsetof(smtp_transport_options_block, dkim.dkim_selector) },
56 { "dkim_sign_headers", opt_stringptr,
57 (void *)offsetof(smtp_transport_options_block, dkim.dkim_sign_headers) },
58 { "dkim_strict", opt_stringptr,
59 (void *)offsetof(smtp_transport_options_block, dkim.dkim_strict) },
61 { "dns_qualify_single", opt_bool,
62 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
63 { "dns_search_parents", opt_bool,
64 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
65 { "dnssec_request_domains", opt_stringptr,
66 (void *)offsetof(smtp_transport_options_block, dnssec.request) },
67 { "dnssec_require_domains", opt_stringptr,
68 (void *)offsetof(smtp_transport_options_block, dnssec.require) },
69 { "dscp", opt_stringptr,
70 (void *)offsetof(smtp_transport_options_block, dscp) },
71 { "fallback_hosts", opt_stringptr,
72 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
73 { "final_timeout", opt_time,
74 (void *)offsetof(smtp_transport_options_block, final_timeout) },
75 { "gethostbyname", opt_bool,
76 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
77 { "helo_data", opt_stringptr,
78 (void *)offsetof(smtp_transport_options_block, helo_data) },
79 { "hosts", opt_stringptr,
80 (void *)offsetof(smtp_transport_options_block, hosts) },
81 { "hosts_avoid_esmtp", opt_stringptr,
82 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
83 { "hosts_avoid_pipelining", opt_stringptr,
84 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
86 { "hosts_avoid_tls", opt_stringptr,
87 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
89 { "hosts_max_try", opt_int,
90 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
91 { "hosts_max_try_hardlimit", opt_int,
92 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
94 { "hosts_nopass_tls", opt_stringptr,
95 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
97 { "hosts_override", opt_bool,
98 (void *)offsetof(smtp_transport_options_block, hosts_override) },
99 { "hosts_randomize", opt_bool,
100 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
101 #if defined(SUPPORT_TLS) && !defined(DISABLE_OCSP)
102 { "hosts_request_ocsp", opt_stringptr,
103 (void *)offsetof(smtp_transport_options_block, hosts_request_ocsp) },
105 { "hosts_require_auth", opt_stringptr,
106 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
108 # ifdef EXPERIMENTAL_DANE
109 { "hosts_require_dane", opt_stringptr,
110 (void *)offsetof(smtp_transport_options_block, hosts_require_dane) },
112 # ifndef DISABLE_OCSP
113 { "hosts_require_ocsp", opt_stringptr,
114 (void *)offsetof(smtp_transport_options_block, hosts_require_ocsp) },
116 { "hosts_require_tls", opt_stringptr,
117 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
119 { "hosts_try_auth", opt_stringptr,
120 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
121 { "hosts_try_chunking", opt_stringptr,
122 (void *)offsetof(smtp_transport_options_block, hosts_try_chunking) },
123 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
124 { "hosts_try_dane", opt_stringptr,
125 (void *)offsetof(smtp_transport_options_block, hosts_try_dane) },
128 { "hosts_try_prdr", opt_stringptr,
129 (void *)offsetof(smtp_transport_options_block, hosts_try_prdr) },
132 { "hosts_verify_avoid_tls", opt_stringptr,
133 (void *)offsetof(smtp_transport_options_block, hosts_verify_avoid_tls) },
135 { "interface", opt_stringptr,
136 (void *)offsetof(smtp_transport_options_block, interface) },
137 { "keepalive", opt_bool,
138 (void *)offsetof(smtp_transport_options_block, keepalive) },
139 { "lmtp_ignore_quota", opt_bool,
140 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
141 { "max_rcpt", opt_int | opt_public,
142 (void *)offsetof(transport_instance, max_addresses) },
143 { "multi_domain", opt_expand_bool | opt_public,
144 (void *)offsetof(transport_instance, multi_domain) },
145 { "port", opt_stringptr,
146 (void *)offsetof(smtp_transport_options_block, port) },
147 { "protocol", opt_stringptr,
148 (void *)offsetof(smtp_transport_options_block, protocol) },
149 { "retry_include_ip_address", opt_expand_bool,
150 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
151 { "serialize_hosts", opt_stringptr,
152 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
153 { "size_addition", opt_int,
154 (void *)offsetof(smtp_transport_options_block, size_addition) }
156 ,{ "socks_proxy", opt_stringptr,
157 (void *)offsetof(smtp_transport_options_block, socks_proxy) }
160 ,{ "tls_certificate", opt_stringptr,
161 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
162 { "tls_crl", opt_stringptr,
163 (void *)offsetof(smtp_transport_options_block, tls_crl) },
164 { "tls_dh_min_bits", opt_int,
165 (void *)offsetof(smtp_transport_options_block, tls_dh_min_bits) },
166 { "tls_privatekey", opt_stringptr,
167 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
168 { "tls_require_ciphers", opt_stringptr,
169 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
170 { "tls_sni", opt_stringptr,
171 (void *)offsetof(smtp_transport_options_block, tls_sni) },
172 { "tls_tempfail_tryclear", opt_bool,
173 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
174 { "tls_try_verify_hosts", opt_stringptr,
175 (void *)offsetof(smtp_transport_options_block, tls_try_verify_hosts) },
176 { "tls_verify_cert_hostnames", opt_stringptr,
177 (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 US"*", /* hosts_try_chunking */
208 #ifdef EXPERIMENTAL_DANE
209 NULL, /* hosts_try_dane */
210 NULL, /* hosts_require_dane */
213 US"*", /* hosts_try_prdr */
216 US"*", /* hosts_request_ocsp (except under DANE; tls_client_start()) */
217 NULL, /* hosts_require_ocsp */
219 NULL, /* hosts_require_tls */
220 NULL, /* hosts_avoid_tls */
221 NULL, /* hosts_verify_avoid_tls */
222 NULL, /* hosts_avoid_pipelining */
223 NULL, /* hosts_avoid_esmtp */
224 NULL, /* hosts_nopass_tls */
225 5*60, /* command_timeout */
226 5*60, /* connect_timeout; shorter system default overrides */
227 5*60, /* data timeout */
228 10*60, /* final timeout */
229 1024, /* size_addition */
230 5, /* hosts_max_try */
231 50, /* hosts_max_try_hardlimit */
232 TRUE, /* address_retry_include_sender */
233 FALSE, /* allow_localhost */
234 FALSE, /* authenticated_sender_force */
235 FALSE, /* gethostbyname */
236 TRUE, /* dns_qualify_single */
237 FALSE, /* dns_search_parents */
238 { NULL, NULL }, /* dnssec_domains {request,require} */
239 TRUE, /* delay_after_cutoff */
240 FALSE, /* hosts_override */
241 FALSE, /* hosts_randomize */
242 TRUE, /* keepalive */
243 FALSE, /* lmtp_ignore_quota */
244 NULL, /* expand_retry_include_ip_address */
245 TRUE /* retry_include_ip_address */
247 ,NULL /* socks_proxy */
250 ,NULL, /* tls_certificate */
252 NULL, /* tls_privatekey */
253 NULL, /* tls_require_ciphers */
255 US"system", /* tls_verify_certificates */
256 EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
257 /* tls_dh_min_bits */
258 TRUE, /* tls_tempfail_tryclear */
259 NULL, /* tls_verify_hosts */
260 US"*", /* tls_try_verify_hosts */
261 US"*" /* tls_verify_cert_hostnames */
264 , {NULL, /* dkim_canon */
265 NULL, /* dkim_domain */
266 NULL, /* dkim_private_key */
267 NULL, /* dkim_selector */
268 NULL, /* dkim_sign_headers */
269 NULL, /* dkim_strict */
270 FALSE} /* dot_stuffed */
274 /* some DSN flags for use later */
276 static int rf_list[] = {rf_notify_never, rf_notify_success,
277 rf_notify_failure, rf_notify_delay };
279 static uschar *rf_names[] = { US"NEVER", US"SUCCESS", US"FAILURE", US"DELAY" };
285 static uschar *smtp_command; /* Points to last cmd for error messages */
286 static uschar *mail_command; /* Points to MAIL cmd for error messages */
287 static BOOL update_waiting; /* TRUE to update the "wait" database */
288 static BOOL pipelining_active; /* current transaction is in pipe mode */
291 /*************************************************
292 * Setup entry point *
293 *************************************************/
295 /* This function is called when the transport is about to be used,
296 but before running it in a sub-process. It is used for two things:
298 (1) To set the fallback host list in addresses, when delivering.
299 (2) To pass back the interface, port, protocol, and other options, for use
300 during callout verification.
303 tblock pointer to the transport instance block
304 addrlist list of addresses about to be transported
305 tf if not NULL, pointer to block in which to return options
306 uid the uid that will be set (not used)
307 gid the gid that will be set (not used)
308 errmsg place for error message (not used)
310 Returns: OK always (FAIL, DEFER not used)
314 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
315 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
317 smtp_transport_options_block *ob =
318 (smtp_transport_options_block *)(tblock->options_block);
320 errmsg = errmsg; /* Keep picky compilers happy */
324 /* Pass back options if required. This interface is getting very messy. */
328 tf->interface = ob->interface;
330 tf->protocol = ob->protocol;
331 tf->hosts = ob->hosts;
332 tf->hosts_override = ob->hosts_override;
333 tf->hosts_randomize = ob->hosts_randomize;
334 tf->gethostbyname = ob->gethostbyname;
335 tf->qualify_single = ob->dns_qualify_single;
336 tf->search_parents = ob->dns_search_parents;
337 tf->helo_data = ob->helo_data;
340 /* Set the fallback host list for all the addresses that don't have fallback
341 host lists, provided that the local host wasn't present in the original host
344 if (!testflag(addrlist, af_local_host_removed))
346 for (; addrlist != NULL; addrlist = addrlist->next)
347 if (addrlist->fallback_hosts == NULL)
348 addrlist->fallback_hosts = ob->fallback_hostlist;
356 /*************************************************
357 * Initialization entry point *
358 *************************************************/
360 /* Called for each instance, after its options have been read, to
361 enable consistency checks to be done, or anything else that needs
364 Argument: pointer to the transport instance block
369 smtp_transport_init(transport_instance *tblock)
371 smtp_transport_options_block *ob =
372 (smtp_transport_options_block *)(tblock->options_block);
374 /* Retry_use_local_part defaults FALSE if unset */
376 if (tblock->retry_use_local_part == TRUE_UNSET)
377 tblock->retry_use_local_part = FALSE;
379 /* Set the default port according to the protocol */
381 if (ob->port == NULL)
382 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
383 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
385 /* Set up the setup entry point, to be called before subprocesses for this
388 tblock->setup = smtp_transport_setup;
390 /* Complain if any of the timeouts are zero. */
392 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
393 ob->final_timeout <= 0)
394 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
395 "command, data, or final timeout value is zero for %s transport",
398 /* If hosts_override is set and there are local hosts, set the global
399 flag that stops verify from showing router hosts. */
401 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
403 /* If there are any fallback hosts listed, build a chain of host items
404 for them, but do not do any lookups at this time. */
406 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
413 /*************************************************
414 * Set delivery info into all active addresses *
415 *************************************************/
417 /* Only addresses whose status is >= PENDING are relevant. A lesser
418 status means that an address is not currently being processed.
421 addrlist points to a chain of addresses
422 errno_value to put in each address's errno field
423 msg to put in each address's message field
424 rc to put in each address's transport_return field
425 pass_message if TRUE, set the "pass message" flag in the address
426 host if set, mark addrs as having used this host
427 smtp_greeting from peer
428 helo_response from peer
430 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
431 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
432 this particular type of timeout.
438 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
439 BOOL pass_message, host_item * host
440 #ifdef EXPERIMENTAL_DSN_INFO
441 , const uschar * smtp_greeting, const uschar * helo_response
447 if (errno_value == ERRNO_CONNECTTIMEOUT)
449 errno_value = ETIMEDOUT;
450 orvalue = RTEF_CTOUT;
452 for (addr = addrlist; addr; addr = addr->next)
453 if (addr->transport_return >= PENDING)
455 addr->basic_errno = errno_value;
456 addr->more_errno |= orvalue;
460 if (pass_message) setflag(addr, af_pass_message);
462 addr->transport_return = rc;
465 addr->host_used = host;
466 #ifdef EXPERIMENTAL_DSN_INFO
468 {uschar * s = Ustrchr(smtp_greeting, '\n'); if (s) *s = '\0';}
469 addr->smtp_greeting = smtp_greeting;
472 {uschar * s = Ustrchr(helo_response, '\n'); if (s) *s = '\0';}
473 addr->helo_response = helo_response;
480 set_errno_nohost(address_item *addrlist, int errno_value, uschar *msg, int rc,
483 set_errno(addrlist, errno_value, msg, rc, pass_message, NULL
484 #ifdef EXPERIMENTAL_DSN_INFO
491 /*************************************************
492 * Check an SMTP response *
493 *************************************************/
495 /* This function is given an errno code and the SMTP response buffer
496 to analyse, together with the host identification for generating messages. It
497 sets an appropriate message and puts the first digit of the response code into
498 the yield variable. If no response was actually read, a suitable digit is
502 host the current host, to get its name for messages
503 errno_value pointer to the errno value
504 more_errno from the top address for use with ERRNO_FILTER_FAIL
505 buffer the SMTP response buffer
506 yield where to put a one-digit SMTP response code
507 message where to put an errror message
508 pass_message set TRUE if message is an SMTP response
510 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
514 check_response(host_item *host, int *errno_value, int more_errno,
515 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
517 uschar * pl = pipelining_active ? US"pipelined " : US"";
519 *yield = '4'; /* Default setting is to give a temporary error */
521 /* Handle response timeout */
523 if (*errno_value == ETIMEDOUT)
525 *message = US string_sprintf("SMTP timeout after %s%s",
527 if (transport_count > 0)
528 *message = US string_sprintf("%s (%d bytes written)", *message,
533 /* Handle malformed SMTP response */
535 if (*errno_value == ERRNO_SMTPFORMAT)
537 const uschar *malfresp = string_printing(buffer);
538 while (isspace(*malfresp)) malfresp++;
539 *message = *malfresp == 0
540 ? string_sprintf("Malformed SMTP reply (an empty line) "
541 "in response to %s%s", pl, smtp_command)
542 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
543 pl, smtp_command, malfresp);
547 /* Handle a failed filter process error; can't send QUIT as we mustn't
550 if (*errno_value == ERRNO_FILTER_FAIL)
552 *message = US string_sprintf("transport filter process failed (%d)%s",
554 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
558 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
561 if (*errno_value == ERRNO_CHHEADER_FAIL)
564 US string_sprintf("failed to expand headers_add or headers_remove: %s",
565 expand_string_message);
569 /* Handle failure to write a complete data block */
571 if (*errno_value == ERRNO_WRITEINCOMPLETE)
573 *message = US string_sprintf("failed to write a data block");
578 /* Handle lack of advertised SMTPUTF8, for international message */
579 if (*errno_value == ERRNO_UTF8_FWD)
581 *message = US string_sprintf("utf8 support required but not offered for forwarding");
582 DEBUG(D_deliver|D_transport) debug_printf("%s\n", *message);
587 /* Handle error responses from the remote mailer. */
591 const uschar *s = string_printing(buffer);
592 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
593 "%s", pl, smtp_command, s);
594 *pass_message = TRUE;
599 /* No data was read. If there is no errno, this must be the EOF (i.e.
600 connection closed) case, which causes deferral. An explicit connection reset
601 error has the same effect. Otherwise, put the host's identity in the message,
602 leaving the errno value to be interpreted as well. In all cases, we have to
603 assume the connection is now dead. */
605 if (*errno_value == 0 || *errno_value == ECONNRESET)
607 *errno_value = ERRNO_SMTPCLOSED;
608 *message = US string_sprintf("Remote host closed connection "
609 "in response to %s%s", pl, smtp_command);
611 else *message = US string_sprintf("%s [%s]", host->name, host->address);
618 /*************************************************
619 * Write error message to logs *
620 *************************************************/
622 /* This writes to the main log and to the message log.
625 addr the address item containing error information
626 host the current host
632 write_logs(address_item *addr, host_item *host)
634 uschar * message = string_sprintf("H=%s [%s]", host->name, host->address);
636 if (LOGGING(outgoing_port))
637 message = string_sprintf("%s:%d", message,
638 host->port == PORT_NONE ? 25 : host->port);
641 message = string_sprintf("%s: %s", message, addr->message);
642 if (addr->basic_errno > 0)
643 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
644 log_write(0, LOG_MAIN, "%s", message);
645 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
649 const uschar * s = exim_errstr(addr->basic_errno);
650 log_write(0, LOG_MAIN, "%s %s", message, s);
651 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), message, s);
656 msglog_line(host_item * host, uschar * message)
658 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
659 host->name, host->address, message);
664 #ifndef DISABLE_EVENT
665 /*************************************************
666 * Post-defer action *
667 *************************************************/
669 /* This expands an arbitrary per-transport string.
670 It might, for example, be used to write to the database log.
673 addr the address item containing error information
674 host the current host
680 deferred_event_raise(address_item *addr, host_item *host)
682 uschar * action = addr->transport->event_action;
683 const uschar * save_domain;
689 save_domain = deliver_domain;
690 save_local = deliver_localpart;
692 /*XXX would ip & port already be set up? */
693 deliver_host_address = string_copy(host->address);
694 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
695 event_defer_errno = addr->basic_errno;
697 router_name = addr->router->name;
698 transport_name = addr->transport->name;
699 deliver_domain = addr->domain;
700 deliver_localpart = addr->local_part;
702 (void) event_raise(action, US"msg:host:defer",
704 ? addr->basic_errno > 0
705 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
706 : string_copy(addr->message)
707 : addr->basic_errno > 0
708 ? string_copy(US strerror(addr->basic_errno))
711 deliver_localpart = save_local;
712 deliver_domain = save_domain;
713 router_name = transport_name = NULL;
717 /*************************************************
718 * Synchronize SMTP responses *
719 *************************************************/
721 /* This function is called from smtp_deliver() to receive SMTP responses from
722 the server, and match them up with the commands to which they relate. When
723 PIPELINING is not in use, this function is called after every command, and is
724 therefore somewhat over-engineered, but it is simpler to use a single scheme
725 that works both with and without PIPELINING instead of having two separate sets
728 The set of commands that are buffered up with pipelining may start with MAIL
729 and may end with DATA; in between are RCPT commands that correspond to the
730 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
731 etc.) are never buffered.
733 Errors after MAIL or DATA abort the whole process leaving the response in the
734 buffer. After MAIL, pending responses are flushed, and the original command is
735 re-instated in big_buffer for error messages. For RCPT commands, the remote is
736 permitted to reject some recipient addresses while accepting others. However
737 certain errors clearly abort the whole process. Set the value in
738 transport_return to PENDING_OK if the address is accepted. If there is a
739 subsequent general error, it will get reset accordingly. If not, it will get
740 converted to OK at the end.
743 addrlist the complete address list
744 include_affixes TRUE if affixes include in RCPT
745 sync_addr ptr to the ptr of the one to start scanning at (updated)
746 host the host we are connected to
747 count the number of responses to read
749 include_sender true if 4xx retry is to include the sender it its key
750 pending_MAIL true if the first response is for MAIL
751 pending_DATA 0 if last command sent was not DATA
752 +1 if previously had a good recipient
753 -1 if not previously had a good recipient
754 inblock incoming SMTP block
755 timeout timeout value
756 buffer buffer for reading response
757 buffsize size of buffer
759 Returns: 3 if at least one address had 2xx and one had 5xx
760 2 if at least one address had 5xx but none had 2xx
761 1 if at least one host had a 2xx response, but none had 5xx
762 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
763 -1 timeout while reading RCPT response
764 -2 I/O or other non-response error for RCPT
765 -3 DATA or MAIL failed - errno and buffer set
769 sync_responses(address_item *addrlist, BOOL include_affixes,
770 address_item **sync_addr, host_item *host, int count,
771 BOOL address_retry_include_sender, BOOL pending_MAIL,
772 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
775 address_item *addr = *sync_addr;
778 /* Handle the response for a MAIL command. On error, reinstate the original
779 command in big_buffer for error message use, and flush any further pending
780 responses before returning, except after I/O errors and timeouts. */
785 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
787 DEBUG(D_transport) debug_printf("bad response for MAIL\n");
788 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
789 if (errno == 0 && buffer[0] != 0)
791 uschar flushbuffer[4096];
793 if (buffer[0] == '4')
795 save_errno = ERRNO_MAIL4XX;
796 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
800 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
802 && (errno != 0 || flushbuffer[0] == 0))
808 if (pending_DATA) count--; /* Number of RCPT responses to come */
809 while (count-- > 0) /* Mark any pending addrs with the host used */
811 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
812 addr->host_used = host;
819 if (pending_DATA) count--; /* Number of RCPT responses to come */
821 /* Read and handle the required number of RCPT responses, matching each one up
822 with an address by scanning for the next address whose status is PENDING_DEFER.
827 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
829 /* The address was accepted */
830 addr->host_used = host;
832 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
835 addr->transport_return = PENDING_OK;
837 /* If af_dr_retry_exists is set, there was a routing delay on this address;
838 ensure that any address-specific retry record is expunged. We do this both
839 for the basic key and for the version that also includes the sender. */
841 if (testflag(addr, af_dr_retry_exists))
843 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
845 retry_add_item(addr, altkey, rf_delete);
846 retry_add_item(addr, addr->address_retry_key, rf_delete);
850 /* Timeout while reading the response */
852 else if (errno == ETIMEDOUT)
854 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
855 transport_rcpt_address(addr, include_affixes));
856 set_errno_nohost(addrlist, ETIMEDOUT, message, DEFER, FALSE);
857 retry_add_item(addr, addr->address_retry_key, 0);
858 update_waiting = FALSE;
862 /* Handle other errors in obtaining an SMTP response by returning -1. This
863 will cause all the addresses to be deferred. Restore the SMTP command in
864 big_buffer for which we are checking the response, so the error message
867 else if (errno != 0 || buffer[0] == 0)
869 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
870 transport_rcpt_address(addr, include_affixes));
874 /* Handle SMTP permanent and temporary response codes. */
879 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
880 "%s", transport_rcpt_address(addr, include_affixes),
881 string_printing(buffer));
882 setflag(addr, af_pass_message);
883 msglog_line(host, addr->message);
885 /* The response was 5xx */
887 if (buffer[0] == '5')
889 addr->transport_return = FAIL;
893 /* The response was 4xx */
897 addr->transport_return = DEFER;
898 addr->basic_errno = ERRNO_RCPT4XX;
899 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
901 #ifndef DISABLE_EVENT
902 event_defer_errno = addr->more_errno;
903 msg_event_raise(US"msg:rcpt:host:defer", addr);
906 /* Log temporary errors if there are more hosts to be tried.
907 If not, log this last one in the == line. */
910 log_write(0, LOG_MAIN, "H=%s [%s]: %s", host->name, host->address, addr->message);
912 #ifndef DISABLE_EVENT
914 msg_event_raise(US"msg:rcpt:defer", addr);
917 /* Do not put this message on the list of those waiting for specific
918 hosts, as otherwise it is likely to be tried too often. */
920 update_waiting = FALSE;
922 /* Add a retry item for the address so that it doesn't get tried again
923 too soon. If address_retry_include_sender is true, add the sender address
926 if (address_retry_include_sender)
928 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
930 retry_add_item(addr, altkey, 0);
932 else retry_add_item(addr, addr->address_retry_key, 0);
935 } /* Loop for next RCPT response */
937 /* Update where to start at for the next block of responses, unless we
938 have already handled all the addresses. */
940 if (addr != NULL) *sync_addr = addr->next;
942 /* Handle a response to DATA. If we have not had any good recipients, either
943 previously or in this block, the response is ignored. */
945 if (pending_DATA != 0 &&
946 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
951 if (pending_DATA > 0 || (yield & 1) != 0)
953 if (errno == 0 && buffer[0] == '4')
955 errno = ERRNO_DATA4XX;
956 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
960 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
961 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
962 "is in use and there were no good recipients\n", msg);
965 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
966 present) received 3xx. If any RCPTs were handled and yielded anything other
967 than 4xx, yield will be set non-zero. */
974 /* Do the client side of smtp-level authentication */
977 buffer EHLO response from server (gets overwritten)
978 addrlist chain of potential addresses to deliver
979 host host to deliver to
981 ibp, obp comms channel control blocks
984 OK Success, or failed (but not required): global "smtp_authenticated" set
985 DEFER Failed authentication (and was required)
986 ERROR Internal problem
988 FAIL_SEND Failed communications - transmit
993 smtp_auth(uschar *buffer, unsigned bufsize, address_item *addrlist, host_item *host,
994 smtp_transport_options_block *ob, BOOL is_esmtp,
995 smtp_inblock *ibp, smtp_outblock *obp)
998 uschar *fail_reason = US"server did not advertise AUTH support";
1000 smtp_authenticated = FALSE;
1001 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
1002 require_auth = verify_check_given_host(&ob->hosts_require_auth, host);
1004 if (is_esmtp && !regex_AUTH) regex_AUTH =
1005 regex_must_compile(US"\\n250[\\s\\-]AUTH\\s+([\\-\\w\\s]+)(?:\\n|$)",
1008 if (is_esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
1010 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
1011 expand_nmax = -1; /* reset */
1013 /* Must not do this check until after we have saved the result of the
1014 regex match above. */
1016 if (require_auth == OK ||
1017 verify_check_given_host(&ob->hosts_try_auth, host) == OK)
1020 fail_reason = US"no common mechanisms were found";
1022 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1024 /* Scan the configured authenticators looking for one which is configured
1025 for use as a client, which is not suppressed by client_condition, and
1026 whose name matches an authentication mechanism supported by the server.
1027 If one is found, attempt to authenticate by calling its client function.
1030 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1034 (au->client_condition != NULL &&
1035 !expand_check_condition(au->client_condition, au->name,
1036 US"client authenticator")))
1038 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1040 (au->client)? "client_condition is false" :
1041 "not configured as a client");
1045 /* Loop to scan supported server mechanisms */
1050 int len = Ustrlen(au->public_name);
1051 while (isspace(*p)) p++;
1053 if (strncmpic(au->public_name, p, len) != 0 ||
1054 (p[len] != 0 && !isspace(p[len])))
1056 while (*p != 0 && !isspace(*p)) p++;
1060 /* Found data for a listed mechanism. Call its client entry. Set
1061 a flag in the outblock so that data is overwritten after sending so
1062 that reflections don't show it. */
1064 fail_reason = US"authentication attempt(s) failed";
1065 obp->authenticating = TRUE;
1066 rc = (au->info->clientcode)(au, ibp, obp,
1067 ob->command_timeout, buffer, bufsize);
1068 obp->authenticating = FALSE;
1069 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1072 /* A temporary authentication failure must hold up delivery to
1073 this host. After a permanent authentication failure, we carry on
1074 to try other authentication methods. If all fail hard, try to
1075 deliver the message unauthenticated unless require_auth was set. */
1080 smtp_authenticated = TRUE; /* stops the outer loop */
1081 client_authenticator = au->name;
1082 if (au->set_client_id != NULL)
1083 client_authenticated_id = expand_string(au->set_client_id);
1086 /* Failure after writing a command */
1091 /* Failure after reading a response */
1094 if (errno != 0 || buffer[0] != '5') return FAIL;
1095 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1096 au->name, host->name, host->address, buffer);
1099 /* Failure by some other means. In effect, the authenticator
1100 decided it wasn't prepared to handle this case. Typically this
1101 is the result of "fail" in an expansion string. Do we need to
1102 log anything here? Feb 2006: a message is now put in the buffer
1103 if logging is required. */
1107 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1108 "authentication H=%s [%s] %s", au->name, host->name,
1109 host->address, buffer);
1112 /* Internal problem, message in buffer. */
1115 set_errno_nohost(addrlist, ERRNO_AUTHPROB, string_copy(buffer),
1120 break; /* If not authenticated, try next authenticator */
1121 } /* Loop for scanning supported server mechanisms */
1122 } /* Loop for further authenticators */
1126 /* If we haven't authenticated, but are required to, give up. */
1128 if (require_auth == OK && !smtp_authenticated)
1130 set_errno_nohost(addrlist, ERRNO_AUTHFAIL,
1131 string_sprintf("authentication required but %s", fail_reason), DEFER,
1140 /* Construct AUTH appendix string for MAIL TO */
1143 buffer to build string
1144 addrlist chain of potential addresses to deliver
1145 ob transport options
1147 Globals smtp_authenticated
1148 client_authenticated_sender
1149 Return True on error, otherwise buffer has (possibly empty) terminated string
1153 smtp_mail_auth_str(uschar *buffer, unsigned bufsize, address_item *addrlist,
1154 smtp_transport_options_block *ob)
1156 uschar *local_authenticated_sender = authenticated_sender;
1159 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n", authenticated_sender, ob->authenticated_sender, smtp_authenticated?"Y":"N");
1162 if (ob->authenticated_sender != NULL)
1164 uschar *new = expand_string(ob->authenticated_sender);
1167 if (!expand_string_forcedfail)
1169 uschar *message = string_sprintf("failed to expand "
1170 "authenticated_sender: %s", expand_string_message);
1171 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1175 else if (new[0] != 0) local_authenticated_sender = new;
1178 /* Add the authenticated sender address if present */
1180 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1181 local_authenticated_sender != NULL)
1183 string_format(buffer, bufsize, " AUTH=%s",
1184 auth_xtextencode(local_authenticated_sender,
1185 Ustrlen(local_authenticated_sender)));
1186 client_authenticated_sender = string_copy(local_authenticated_sender);
1196 #ifdef EXPERIMENTAL_DANE
1197 /* Lookup TLSA record for host/port.
1198 Return: OK success with dnssec; DANE mode
1199 DEFER Do not use this host now, may retry later
1200 FAIL_FORCED No TLSA record; DANE not usable
1201 FAIL Do not use this connection
1205 tlsa_lookup(const host_item * host, dns_answer * dnsa, BOOL dane_required)
1207 /* move this out to host.c given the similarity to dns_lookup() ? */
1209 const uschar * fullname = buffer;
1211 /* TLSA lookup string */
1212 (void)sprintf(CS buffer, "_%d._tcp.%.256s", host->port, host->name);
1214 switch (dns_lookup(dnsa, buffer, T_TLSA, &fullname))
1217 if (!dns_is_secure(dnsa))
1219 log_write(0, LOG_MAIN, "DANE error: TLSA lookup not DNSSEC");
1225 return DEFER; /* just defer this TLS'd conn */
1227 case DNS_NODATA: /* no TLSA RR for this lookup */
1228 case DNS_NOMATCH: /* no records at all for this lookup */
1229 return dane_required ? FAIL : FAIL_FORCED;
1233 return dane_required ? FAIL : DEFER;
1240 typedef struct smtp_compare_s
1242 uschar *current_sender_address;
1243 struct transport_instance *tblock;
1247 Create a unique string that identifies this message, it is based on
1248 sender_address, helo_data and tls_certificate if enabled. */
1251 smtp_local_identity(uschar * sender, struct transport_instance * tblock)
1253 address_item * addr1;
1254 uschar * if1 = US"";
1255 uschar * helo1 = US"";
1257 uschar * tlsc1 = US"";
1259 uschar * save_sender_address = sender_address;
1260 uschar * local_identity = NULL;
1261 smtp_transport_options_block * ob =
1262 (smtp_transport_options_block *)tblock->options_block;
1264 sender_address = sender;
1266 addr1 = deliver_make_addr (sender, TRUE);
1267 deliver_set_expansions(addr1);
1270 if1 = expand_string(ob->interface);
1273 helo1 = expand_string(ob->helo_data);
1276 if (ob->tls_certificate)
1277 tlsc1 = expand_string(ob->tls_certificate);
1278 local_identity = string_sprintf ("%s^%s^%s", if1, helo1, tlsc1);
1280 local_identity = string_sprintf ("%s^%s", if1, helo1);
1283 deliver_set_expansions(NULL);
1284 sender_address = save_sender_address;
1286 return local_identity;
1291 /* This routine is a callback that is called from transport_check_waiting.
1292 This function will evaluate the incoming message versus the previous
1293 message. If the incoming message is using a different local identity then
1294 we will veto this new message. */
1297 smtp_are_same_identities(uschar * message_id, smtp_compare_t * s_compare)
1299 uschar * message_local_identity,
1300 * current_local_identity,
1301 * new_sender_address;
1303 current_local_identity =
1304 smtp_local_identity(s_compare->current_sender_address, s_compare->tblock);
1306 if (!(new_sender_address = deliver_get_sender_address(message_id)))
1309 message_local_identity =
1310 smtp_local_identity(new_sender_address, s_compare->tblock);
1312 return Ustrcmp(current_local_identity, message_local_identity) == 0;
1318 ehlo_response(uschar * buf, size_t bsize, uschar checks)
1321 if ( checks & PEER_OFFERED_TLS
1322 && pcre_exec(regex_STARTTLS, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1323 checks &= ~PEER_OFFERED_TLS;
1326 if ( checks & PEER_OFFERED_IGNQ
1327 && pcre_exec(regex_IGNOREQUOTA, NULL, CS buf, bsize, 0,
1328 PCRE_EOPT, NULL, 0) < 0)
1329 checks &= ~PEER_OFFERED_IGNQ;
1331 if ( checks & PEER_OFFERED_CHUNKING
1332 && pcre_exec(regex_CHUNKING, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1333 checks &= ~PEER_OFFERED_CHUNKING;
1335 #ifndef DISABLE_PRDR
1336 if ( checks & PEER_OFFERED_PRDR
1337 && pcre_exec(regex_PRDR, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1338 checks &= ~PEER_OFFERED_PRDR;
1342 if ( checks & PEER_OFFERED_UTF8
1343 && pcre_exec(regex_UTF8, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1344 checks &= ~PEER_OFFERED_UTF8;
1347 if ( checks & PEER_OFFERED_DSN
1348 && pcre_exec(regex_DSN, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1349 checks &= ~PEER_OFFERED_DSN;
1351 if ( checks & PEER_OFFERED_PIPE
1352 && pcre_exec(regex_PIPELINING, NULL, CS buf, bsize, 0,
1353 PCRE_EOPT, NULL, 0) < 0)
1354 checks &= ~PEER_OFFERED_PIPE;
1356 if ( checks & PEER_OFFERED_SIZE
1357 && pcre_exec(regex_SIZE, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1358 checks &= ~PEER_OFFERED_SIZE;
1365 /* Callback for emitting a BDAT data chunk header.
1367 If given a nonzero size, first flush any buffered SMTP commands
1368 then emit the command.
1370 Reap previous SMTP command responses if requested.
1371 Reap one SMTP command response if requested.
1373 Returns: OK or ERROR
1377 smtp_chunk_cmd_callback(int fd, transport_ctx * tctx,
1378 unsigned chunk_size, unsigned flags)
1380 smtp_transport_options_block * ob =
1381 (smtp_transport_options_block *)(tctx->tblock->options_block);
1384 uschar * buffer = tctx->buffer;
1387 /* Write SMTP chunk header command */
1390 if((cmd_count = smtp_write_command(tctx->outblock, FALSE, "BDAT %u%s\r\n",
1392 flags & tc_chunk_last ? " LAST" : "")
1393 ) < 0) return ERROR;
1395 prev_cmd_count = cmd_count += tctx->cmd_count;
1397 /* Reap responses for any previous, but not one we just emitted */
1401 if (tctx->pending_BDAT)
1404 if (flags & tc_reap_prev && prev_cmd_count > 0)
1406 DEBUG(D_transport) debug_printf("look for %d responses"
1407 " for previous pipelined cmds\n", prev_cmd_count);
1409 switch(sync_responses(tctx->first_addr, tctx->tblock->rcpt_include_affixes,
1410 tctx->sync_addr, tctx->host, prev_cmd_count,
1411 ob->address_retry_include_sender,
1412 tctx->pending_MAIL, 0,
1414 ob->command_timeout,
1415 buffer, DELIVER_BUFFER_SIZE))
1417 case 1: /* 2xx (only) => OK */
1418 case 3: tctx->good_RCPT = TRUE; /* 2xx & 5xx => OK & progress made */
1419 case 2: *tctx->completed_address = TRUE; /* 5xx (only) => progress made */
1420 case 0: break; /* No 2xx or 5xx, but no probs */
1422 case -1: /* Timeout on RCPT */
1423 default: return ERROR; /* I/O error, or any MAIL/DATA error */
1426 if (!tctx->pending_BDAT)
1427 pipelining_active = FALSE;
1430 /* Reap response for an outstanding BDAT */
1432 if (tctx->pending_BDAT)
1434 DEBUG(D_transport) debug_printf("look for one response for BDAT\n");
1436 if (!smtp_read_response(tctx->inblock, buffer, DELIVER_BUFFER_SIZE, '2',
1437 ob->command_timeout))
1439 if (errno == 0 && buffer[0] == '4')
1441 errno = ERRNO_DATA4XX; /*XXX does this actually get used? */
1442 tctx->first_addr->more_errno |=
1443 ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1448 tctx->pending_BDAT = FALSE;
1449 pipelining_active = FALSE;
1451 else if (chunk_size > 0)
1452 tctx->pending_BDAT = TRUE;
1455 tctx->cmd_count = cmd_count;
1461 /*************************************************
1462 * Deliver address list to given host *
1463 *************************************************/
1465 /* If continue_hostname is not null, we get here only when continuing to
1466 deliver down an existing channel. The channel was passed as the standard
1467 input. TLS is never active on a passed channel; the previous process always
1468 closes it down before passing the connection on.
1470 Otherwise, we have to make a connection to the remote host, and do the
1471 initial protocol exchange.
1473 When running as an MUA wrapper, if the sender or any recipient is rejected,
1474 temporarily or permanently, we force failure for all recipients.
1477 addrlist chain of potential addresses to deliver; only those whose
1478 transport_return field is set to PENDING_DEFER are currently
1479 being processed; others should be skipped - they have either
1480 been delivered to an earlier host or IP address, or been
1481 failed by one of them.
1482 host host to deliver to
1483 host_af AF_INET or AF_INET6
1484 port default TCP/IP port to use, in host byte order
1485 interface interface to bind to, or NULL
1486 tblock transport instance block
1487 message_defer set TRUE if yield is OK, but all addresses were deferred
1488 because of a non-recipient, non-host failure, that is, a
1489 4xx response to MAIL FROM, DATA, or ".". This is a defer
1490 that is specific to the message.
1491 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1492 a second attempt after TLS initialization fails
1494 Returns: OK - the connection was made and the delivery attempted;
1495 the result for each address is in its data block.
1496 DEFER - the connection could not be made, or something failed
1497 while setting up the SMTP session, or there was a
1498 non-message-specific error, such as a timeout.
1499 ERROR - a filter command is specified for this transport,
1500 and there was a problem setting it up; OR helo_data
1501 or add_headers or authenticated_sender is specified
1502 for this transport, and the string failed to expand
1506 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
1507 uschar *interface, transport_instance *tblock,
1508 BOOL *message_defer, BOOL suppress_tls)
1511 address_item *sync_addr;
1512 address_item *first_addr = addrlist;
1517 time_t start_delivery_time = time(NULL);
1518 smtp_transport_options_block *ob =
1519 (smtp_transport_options_block *)(tblock->options_block);
1528 BOOL pending_MAIL:1;
1529 #ifndef DISABLE_PRDR
1535 BOOL dsn_all_lasthop:1;
1536 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1538 BOOL dane_required:1;
1542 BOOL pass_message = FALSE;
1543 BOOL completed_address = FALSE;
1544 uschar peer_offered = 0;
1545 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1546 dns_answer tlsa_dnsa;
1548 smtp_inblock inblock;
1549 smtp_outblock outblock;
1550 int max_rcpt = tblock->max_addresses;
1551 uschar *igquotstr = US"";
1553 #ifdef EXPERIMENTAL_DSN_INFO
1554 uschar *smtp_greeting = NULL;
1555 uschar *helo_response = NULL;
1557 uschar *helo_data = NULL;
1559 uschar *message = NULL;
1560 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
1562 uschar buffer[DELIVER_BUFFER_SIZE];
1563 uschar inbuffer[4096];
1564 uschar outbuffer[4096];
1566 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
1568 lflags.lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
1569 lflags.smtps = strcmpic(ob->protocol, US"smtps") == 0;
1571 lflags.send_rset = TRUE;
1572 lflags.send_quit = TRUE;
1573 lflags.setting_up = TRUE;
1574 lflags.esmtp = TRUE;
1575 lflags.pending_MAIL;
1576 #ifndef DISABLE_PRDR
1580 lflags.utf8_needed = FALSE;
1582 lflags.dsn_all_lasthop = TRUE;
1583 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1584 lflags.dane = FALSE;
1585 lflags.dane_required = verify_check_given_host(&ob->hosts_require_dane, host) == OK;
1588 *message_defer = FALSE;
1589 smtp_command = US"initial connection";
1590 if (max_rcpt == 0) max_rcpt = 999999;
1592 /* Set up the buffer for reading SMTP response packets. */
1594 inblock.buffer = inbuffer;
1595 inblock.buffersize = sizeof(inbuffer);
1596 inblock.ptr = inbuffer;
1597 inblock.ptrend = inbuffer;
1599 /* Set up the buffer for holding SMTP commands while pipelining */
1601 outblock.buffer = outbuffer;
1602 outblock.buffersize = sizeof(outbuffer);
1603 outblock.ptr = outbuffer;
1604 outblock.cmd_count = 0;
1605 outblock.authenticating = FALSE;
1607 /* Reset the parameters of a TLS session. */
1610 tls_out.cipher = NULL; /* the one we may use for this transport */
1611 tls_out.ourcert = NULL;
1612 tls_out.peercert = NULL;
1613 tls_out.peerdn = NULL;
1614 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1617 tls_out.ocsp = OCSP_NOT_REQ;
1619 /* Flip the legacy TLS-related variables over to the outbound set in case
1620 they're used in the context of the transport. Don't bother resetting
1621 afterward as we're in a subprocess. */
1623 tls_modify_variables(&tls_out);
1628 set_errno_nohost(addrlist, ERRNO_TLSFAILURE, US"TLS support not available",
1634 /* Make a connection to the host if this isn't a continued delivery, and handle
1635 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
1636 specially so they can be identified for retries. */
1638 if (continue_hostname == NULL)
1640 /* This puts port into host->port */
1641 inblock.sock = outblock.sock =
1642 smtp_connect(host, host_af, port, interface, ob->connect_timeout, tblock);
1644 if (inblock.sock < 0)
1646 set_errno_nohost(addrlist, errno == ETIMEDOUT ? ERRNO_CONNECTTIMEOUT : errno,
1647 NULL, DEFER, FALSE);
1651 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1653 tls_out.dane_verified = FALSE;
1654 tls_out.tlsa_usage = 0;
1656 if (host->dnssec == DS_YES)
1658 if( lflags.dane_required
1659 || verify_check_given_host(&ob->hosts_try_dane, host) == OK
1661 switch (rc = tlsa_lookup(host, &tlsa_dnsa, lflags.dane_required))
1663 case OK: lflags.dane = TRUE; break;
1664 case FAIL_FORCED: break;
1665 default: set_errno_nohost(addrlist, ERRNO_DNSDEFER,
1666 string_sprintf("DANE error: tlsa lookup %s",
1667 rc == DEFER ? "DEFER" : "FAIL"),
1672 else if (lflags.dane_required)
1674 set_errno_nohost(addrlist, ERRNO_DNSDEFER,
1675 string_sprintf("DANE error: %s lookup not DNSSEC", host->name),
1681 ob->tls_tempfail_tryclear = FALSE;
1685 /* Expand the greeting message while waiting for the initial response. (Makes
1686 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1687 delayed till here so that $sending_interface and $sending_port are set. */
1689 helo_data = expand_string(ob->helo_data);
1693 uschar * errstr = NULL;
1694 if ((helo_data = string_domain_utf8_to_alabel(helo_data, &errstr)), errstr)
1696 errstr = string_sprintf("failed to expand helo_data: %s", errstr);
1697 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE);
1704 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1705 is nevertheless a reasonably clean way of programming this kind of logic,
1706 where you want to escape on any error. */
1710 BOOL good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
1711 '2', ob->command_timeout);
1712 #ifdef EXPERIMENTAL_DSN_INFO
1713 smtp_greeting = string_copy(buffer);
1715 if (!good_response) goto RESPONSE_FAILED;
1717 #ifndef DISABLE_EVENT
1720 lookup_dnssec_authenticated = host->dnssec==DS_YES ? US"yes"
1721 : host->dnssec==DS_NO ? US"no" : NULL;
1722 s = event_raise(tblock->event_action, US"smtp:connect", buffer);
1725 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL,
1726 string_sprintf("deferred by smtp:connect event expansion: %s", s),
1734 /* Now check if the helo_data expansion went well, and sign off cleanly if
1737 if (helo_data == NULL)
1739 uschar *message = string_sprintf("failed to expand helo_data: %s",
1740 expand_string_message);
1741 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1747 /** Debugging without sending a message
1748 addrlist->transport_return = DEFER;
1752 /* Errors that occur after this point follow an SMTP command, which is
1753 left in big_buffer by smtp_write_command() for use in error messages. */
1755 smtp_command = big_buffer;
1757 /* Tell the remote who we are...
1759 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1760 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1761 greeting is of this form. The assumption was that the far end supports it
1762 properly... but experience shows that there are some that give 5xx responses,
1763 even though the banner includes "ESMTP" (there's a bloody-minded one that
1764 says "ESMTP not spoken here"). Cope with that case.
1766 September 2000: Time has passed, and it seems reasonable now to always send
1767 EHLO at the start. It is also convenient to make the change while installing
1770 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1771 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1772 would be no way to send out the mails, so there is now a host list
1773 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1774 PIPELINING problem as well. Maybe it can also be useful to cure other
1775 problems with broken servers.
1777 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1778 Then somebody tried it with a Microsoft mailer... It seems that all other
1779 mailers use upper case for some reason (the RFC is quite clear about case
1780 independence) so, for peace of mind, I gave in. */
1782 lflags.esmtp = verify_check_given_host(&ob->hosts_avoid_esmtp, host) != OK;
1784 /* Alas; be careful, since this goto is not an error-out, so conceivably
1785 we might set data between here and the target which we assume to exist
1786 and be usable. I can see this coming back to bite us. */
1790 smtp_peer_options |= PEER_OFFERED_TLS;
1791 suppress_tls = FALSE;
1792 ob->tls_tempfail_tryclear = FALSE;
1793 smtp_command = US"SSL-on-connect";
1800 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1801 lflags.lmtp ? "LHLO" : "EHLO", helo_data) < 0)
1803 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1804 ob->command_timeout))
1806 if (errno != 0 || buffer[0] == 0 || lflags.lmtp)
1808 #ifdef EXPERIMENTAL_DSN_INFO
1809 helo_response = string_copy(buffer);
1811 goto RESPONSE_FAILED;
1813 lflags.esmtp = FALSE;
1815 #ifdef EXPERIMENTAL_DSN_INFO
1816 helo_response = string_copy(buffer);
1821 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1827 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1829 good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
1830 '2', ob->command_timeout);
1831 #ifdef EXPERIMENTAL_DSN_INFO
1832 helo_response = string_copy(buffer);
1834 if (!good_response) goto RESPONSE_FAILED;
1837 peer_offered = smtp_peer_options = 0;
1839 if (lflags.esmtp || lflags.lmtp)
1841 peer_offered = ehlo_response(buffer, Ustrlen(buffer),
1842 PEER_OFFERED_TLS /* others checked later */
1845 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1848 smtp_peer_options |= peer_offered & PEER_OFFERED_TLS;
1853 /* For continuing deliveries down the same channel, the socket is the standard
1854 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1855 below). Set up the pointer to where subsequent commands will be left, for
1856 error messages. Note that smtp_peer_options will have been
1857 set from the command line if they were set in the process that passed the
1860 /*XXX continue case needs to propagate DSN_INFO, prob. in deliver.c
1861 as the contine goes via transport_pass_socket() and doublefork and exec.
1862 It does not wait. Unclear how we keep separate host's responses
1863 separate - we could match up by host ip+port as a bodge. */
1867 inblock.sock = outblock.sock = fileno(stdin);
1868 smtp_command = big_buffer;
1869 host->port = port; /* Record the port that was used */
1872 /* If TLS is available on this connection, whether continued or not, attempt to
1873 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1874 send another EHLO - the server may give a different answer in secure mode. We
1875 use a separate buffer for reading the response to STARTTLS so that if it is
1876 negative, the original EHLO data is available for subsequent analysis, should
1877 the client not be required to use TLS. If the response is bad, copy the buffer
1878 for error analysis. */
1881 if ( smtp_peer_options & PEER_OFFERED_TLS
1883 && verify_check_given_host(&ob->hosts_avoid_tls, host) != OK)
1885 uschar buffer2[4096];
1886 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1889 /* If there is an I/O error, transmission of this message is deferred. If
1890 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1891 false, we also defer. However, if there is a temporary rejection of STARTTLS
1892 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1893 STARTTLS, we carry on. This means we will try to send the message in clear,
1894 unless the host is in hosts_require_tls (tested below). */
1896 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1897 ob->command_timeout))
1901 || (buffer2[0] == '4' && !ob->tls_tempfail_tryclear)
1904 Ustrncpy(buffer, buffer2, sizeof(buffer));
1905 goto RESPONSE_FAILED;
1909 /* STARTTLS accepted: try to negotiate a TLS session. */
1914 int rc = tls_client_start(inblock.sock, host, addrlist, tblock
1915 # ifdef EXPERIMENTAL_DANE
1916 , lflags.dane ? &tlsa_dnsa : NULL
1920 /* TLS negotiation failed; give an error. From outside, this function may
1921 be called again to try in clear on a new connection, if the options permit
1922 it for this host. */
1926 # ifdef EXPERIMENTAL_DANE
1927 if (rc == DEFER && lflags.dane)
1929 log_write(0, LOG_MAIN,
1930 "DANE attempt failed; no TLS connection to %s [%s]",
1931 host->name, host->address);
1935 save_errno = ERRNO_TLSFAILURE;
1936 message = US"failure while setting up TLS session";
1937 lflags.send_quit = FALSE;
1941 /* TLS session is set up */
1943 smtp_peer_options_wrap = smtp_peer_options;
1944 for (addr = addrlist; addr; addr = addr->next)
1945 if (addr->transport_return == PENDING_DEFER)
1947 addr->cipher = tls_out.cipher;
1948 addr->ourcert = tls_out.ourcert;
1949 addr->peercert = tls_out.peercert;
1950 addr->peerdn = tls_out.peerdn;
1951 addr->ocsp = tls_out.ocsp;
1956 /* if smtps, we'll have smtp_command set to something else; always safe to
1958 smtp_command = big_buffer;
1960 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1961 helo_data is null, we are dealing with a connection that was passed from
1962 another process, and so we won't have expanded helo_data above. We have to
1963 expand it here. $sending_ip_address and $sending_port are set up right at the
1964 start of the Exim process (in exim.c). */
1966 if (tls_out.active >= 0)
1971 if (helo_data == NULL)
1973 helo_data = expand_string(ob->helo_data);
1974 if (helo_data == NULL)
1976 uschar *message = string_sprintf("failed to expand helo_data: %s",
1977 expand_string_message);
1978 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1984 /* For SMTPS we need to wait for the initial OK response. */
1987 good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
1988 '2', ob->command_timeout);
1989 #ifdef EXPERIMENTAL_DSN_INFO
1990 smtp_greeting = string_copy(buffer);
1992 if (!good_response) goto RESPONSE_FAILED;
1996 greeting_cmd = "EHLO";
1999 greeting_cmd = "HELO";
2001 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
2004 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
2005 lflags.lmtp ? "LHLO" : greeting_cmd, helo_data) < 0)
2007 good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
2008 '2', ob->command_timeout);
2009 #ifdef EXPERIMENTAL_DSN_INFO
2010 helo_response = string_copy(buffer);
2012 if (!good_response) goto RESPONSE_FAILED;
2013 smtp_peer_options = 0;
2016 /* If the host is required to use a secure channel, ensure that we
2019 else if ( lflags.smtps
2020 # ifdef EXPERIMENTAL_DANE
2023 || verify_check_given_host(&ob->hosts_require_tls, host) == OK
2026 save_errno = ERRNO_TLSREQUIRED;
2027 message = string_sprintf("a TLS session is required, but %s",
2028 smtp_peer_options & PEER_OFFERED_TLS
2029 ? "an attempt to start TLS failed" : "the server did not offer TLS support");
2032 #endif /*SUPPORT_TLS*/
2034 /* If TLS is active, we have just started it up and re-done the EHLO command,
2035 so its response needs to be analyzed. If TLS is not active and this is a
2036 continued session down a previously-used socket, we haven't just done EHLO, so
2039 if (continue_hostname == NULL
2041 || tls_out.active >= 0
2045 if (lflags.esmtp || lflags.lmtp)
2047 peer_offered = ehlo_response(buffer, Ustrlen(buffer),
2049 | (lflags.lmtp && ob->lmtp_ignore_quota ? PEER_OFFERED_IGNQ : 0)
2050 | PEER_OFFERED_CHUNKING
2053 | (addrlist->prop.utf8_msg ? PEER_OFFERED_UTF8 : 0)
2054 /*XXX if we hand peercaps on to continued-conn processes,
2055 must not depend on this addr */
2059 | (ob->size_addition >= 0 ? PEER_OFFERED_SIZE : 0)
2062 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
2063 lmtp_ignore_quota option was set. */
2065 igquotstr = peer_offered & PEER_OFFERED_IGNQ ? US" IGNOREQUOTA" : US"";
2067 /* If the response to EHLO specified support for the SIZE parameter, note
2068 this, provided size_addition is non-negative. */
2070 smtp_peer_options |= peer_offered & PEER_OFFERED_SIZE;
2072 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
2073 the current host, esmtp will be false, so PIPELINING can never be used. If
2074 the current host matches hosts_avoid_pipelining, don't do it. */
2076 if ( peer_offered & PEER_OFFERED_PIPE
2077 && verify_check_given_host(&ob->hosts_avoid_pipelining, host) != OK)
2078 smtp_peer_options |= PEER_OFFERED_PIPE;
2080 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
2081 smtp_peer_options & PEER_OFFERED_PIPE ? "" : "not ");
2083 if ( peer_offered & PEER_OFFERED_CHUNKING
2084 && verify_check_given_host(&ob->hosts_try_chunking, host) != OK)
2085 peer_offered &= ~PEER_OFFERED_CHUNKING;
2087 if (peer_offered & PEER_OFFERED_CHUNKING)
2088 {DEBUG(D_transport) debug_printf("CHUNKING usable\n");}
2090 #ifndef DISABLE_PRDR
2091 if ( peer_offered & PEER_OFFERED_PRDR
2092 && verify_check_given_host(&ob->hosts_try_prdr, host) != OK)
2093 peer_offered &= ~PEER_OFFERED_PRDR;
2095 if (peer_offered & PEER_OFFERED_PRDR)
2096 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
2099 /* Note if the server supports DSN */
2100 smtp_peer_options |= peer_offered & PEER_OFFERED_DSN;
2101 DEBUG(D_transport) debug_printf("%susing DSN\n",
2102 peer_offered & PEER_OFFERED_DSN ? "" : "not ");
2104 /* Note if the response to EHLO specifies support for the AUTH extension.
2105 If it has, check that this host is one we want to authenticate to, and do
2106 the business. The host name and address must be available when the
2107 authenticator's client driver is running. */
2109 switch (yield = smtp_auth(buffer, sizeof(buffer), addrlist, host,
2110 ob, lflags.esmtp, &inblock, &outblock))
2112 default: goto SEND_QUIT;
2114 case FAIL_SEND: goto SEND_FAILED;
2115 case FAIL: goto RESPONSE_FAILED;
2119 pipelining_active = !!(smtp_peer_options & PEER_OFFERED_PIPE);
2121 /* The setting up of the SMTP call is now complete. Any subsequent errors are
2122 message-specific. */
2124 lflags.setting_up = FALSE;
2127 if (addrlist->prop.utf8_msg)
2129 lflags.utf8_needed = !addrlist->prop.utf8_downcvt
2130 && !addrlist->prop.utf8_downcvt_maybe;
2131 DEBUG(D_transport) if (!lflags.utf8_needed)
2132 debug_printf("utf8: %s downconvert\n",
2133 addrlist->prop.utf8_downcvt ? "mandatory" : "optional");
2136 /* If this is an international message we need the host to speak SMTPUTF8 */
2137 if (lflags.utf8_needed && !(peer_offered & PEER_OFFERED_UTF8))
2139 errno = ERRNO_UTF8_FWD;
2140 goto RESPONSE_FAILED;
2144 /* If there is a filter command specified for this transport, we can now
2145 set it up. This cannot be done until the identify of the host is known. */
2147 if (tblock->filter_command != NULL)
2151 sprintf(CS buffer, "%.50s transport", tblock->name);
2152 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
2153 TRUE, DEFER, addrlist, buffer, NULL);
2154 transport_filter_timeout = tblock->filter_timeout;
2156 /* On failure, copy the error to all addresses, abandon the SMTP call, and
2161 set_errno_nohost(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
2167 if ( transport_filter_argv
2168 && *transport_filter_argv
2169 && **transport_filter_argv
2170 && peer_offered & PEER_OFFERED_CHUNKING
2173 peer_offered &= ~PEER_OFFERED_CHUNKING;
2174 DEBUG(D_transport) debug_printf("CHUNKING not usable due to transport filter\n");
2179 /* For messages that have more than the maximum number of envelope recipients,
2180 we want to send several transactions down the same SMTP connection. (See
2181 comments in deliver.c as to how this reconciles, heuristically, with
2182 remote_max_parallel.) This optimization was added to Exim after the following
2183 code was already working. The simplest way to put it in without disturbing the
2184 code was to use a goto to jump back to this point when there is another
2185 transaction to handle. */
2188 sync_addr = first_addr;
2191 lflags.send_rset = TRUE;
2192 completed_address = FALSE;
2195 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
2196 qualification, send it, adding something to the message size to allow for
2197 imprecision and things that get added en route. Exim keeps the number of lines
2198 in a message, so we can give an accurate value for the original message, but we
2199 need some additional to handle added headers. (Double "." characters don't get
2200 included in the count.) */
2205 if (peer_offered & PEER_OFFERED_SIZE)
2207 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
2211 #ifndef DISABLE_PRDR
2212 lflags.prdr_active = FALSE;
2213 if (peer_offered & PEER_OFFERED_PRDR)
2214 for (addr = first_addr; addr; addr = addr->next)
2215 if (addr->transport_return == PENDING_DEFER)
2217 for (addr = addr->next; addr; addr = addr->next)
2218 if (addr->transport_return == PENDING_DEFER)
2219 { /* at least two recipients to send */
2220 lflags.prdr_active = TRUE;
2221 sprintf(CS p, " PRDR"); p += 5;
2229 if ( addrlist->prop.utf8_msg
2230 && !addrlist->prop.utf8_downcvt
2231 && peer_offered & PEER_OFFERED_UTF8
2233 sprintf(CS p, " SMTPUTF8"), p += 9;
2236 /* check if all addresses have lasthop flag */
2237 /* do not send RET and ENVID if true */
2238 for (lflags.dsn_all_lasthop = TRUE, addr = first_addr;
2239 address_count < max_rcpt && addr != NULL;
2241 if ((addr->dsn_flags & rf_dsnlasthop) != 1)
2243 lflags.dsn_all_lasthop = FALSE;
2247 /* Add any DSN flags to the mail command */
2249 if (peer_offered & PEER_OFFERED_DSN && !lflags.dsn_all_lasthop)
2251 if (dsn_ret == dsn_ret_hdrs)
2252 { Ustrcpy(p, " RET=HDRS"); p += 9; }
2253 else if (dsn_ret == dsn_ret_full)
2254 { Ustrcpy(p, " RET=FULL"); p += 9; }
2258 string_format(p, sizeof(buffer) - (p-buffer), " ENVID=%s", dsn_envid);
2263 /* If an authenticated_sender override has been specified for this transport
2264 instance, expand it. If the expansion is forced to fail, and there was already
2265 an authenticated_sender for this message, the original value will be used.
2266 Other expansion failures are serious. An empty result is ignored, but there is
2267 otherwise no check - this feature is expected to be used with LMTP and other
2268 cases where non-standard addresses (e.g. without domains) might be required. */
2270 if (smtp_mail_auth_str(p, sizeof(buffer) - (p-buffer), addrlist, ob))
2276 /* From here until we send the DATA command, we can make use of PIPELINING
2277 if the server host supports it. The code has to be able to check the responses
2278 at any point, for when the buffer fills up, so we write it totally generally.
2279 When PIPELINING is off, each command written reports that it has flushed the
2282 lflags.pending_MAIL = TRUE; /* The block starts with MAIL */
2285 uschar * s = return_path;
2287 uschar * errstr = NULL;
2289 /* If we must downconvert, do the from-address here. Remember we had to
2290 for the to-addresses (done below), and also (ugly) for re-doing when building
2291 the delivery log line. */
2293 if ( addrlist->prop.utf8_msg
2294 && (addrlist->prop.utf8_downcvt || !(peer_offered & PEER_OFFERED_UTF8))
2297 if (s = string_address_utf8_to_alabel(return_path, &errstr), errstr)
2299 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE);
2303 setflag(addrlist, af_utf8_downcvt);
2307 rc = smtp_write_command(&outblock, pipelining_active,
2308 "MAIL FROM:<%s>%s\r\n", s, buffer);
2311 mail_command = string_copy(big_buffer); /* Save for later error message */
2315 case -1: /* Transmission error */
2318 case +1: /* Block was sent */
2319 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2320 ob->command_timeout))
2322 if (errno == 0 && buffer[0] == '4')
2324 errno = ERRNO_MAIL4XX;
2325 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2327 goto RESPONSE_FAILED;
2329 lflags.pending_MAIL = FALSE;
2333 /* Pass over all the relevant recipient addresses for this host, which are the
2334 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
2335 several before we have to read the responses for those seen so far. This
2336 checking is done by a subroutine because it also needs to be done at the end.
2337 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
2338 the next one if not all are sent.
2340 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
2341 last address because we want to abort if any recipients have any kind of
2342 problem, temporary or permanent. We know that all recipient addresses will have
2343 the PENDING_DEFER status, because only one attempt is ever made, and we know
2344 that max_rcpt will be large, so all addresses will be done at once. */
2346 for (addr = first_addr;
2347 addr && address_count < max_rcpt;
2349 if (addr->transport_return == PENDING_DEFER)
2355 addr->dsn_aware = peer_offered & PEER_OFFERED_DSN
2356 ? dsn_support_yes : dsn_support_no;
2359 no_flush = pipelining_active && (!mua_wrapper || addr->next);
2361 /* Add any DSN flags to the rcpt command and add to the sent string */
2366 if (peer_offered & PEER_OFFERED_DSN && !(addr->dsn_flags & rf_dsnlasthop))
2368 if (addr->dsn_flags & rf_dsnflags)
2372 Ustrcpy(p, " NOTIFY=");
2374 for (i = 0; i < 4; i++)
2375 if ((addr->dsn_flags & rf_list[i]) != 0)
2377 if (!first) *p++ = ',';
2379 Ustrcpy(p, rf_names[i]);
2384 if (addr->dsn_orcpt)
2386 string_format(p, sizeof(buffer) - (p-buffer), " ORCPT=%s",
2392 /* Now send the RCPT command, and process outstanding responses when
2393 necessary. After a timeout on RCPT, we just end the function, leaving the
2394 yield as OK, because this error can often mean that there is a problem with
2395 just one address, so we don't want to delay the host. */
2397 rcpt_addr = transport_rcpt_address(addr, tblock->rcpt_include_affixes);
2401 uschar * dummy_errstr;
2402 if ( testflag(addrlist, af_utf8_downcvt)
2403 && (rcpt_addr = string_address_utf8_to_alabel(rcpt_addr, &dummy_errstr),
2407 errno = ERRNO_EXPANDFAIL;
2413 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s%s\r\n",
2414 rcpt_addr, igquotstr, buffer);
2416 if (count < 0) goto SEND_FAILED;
2419 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
2420 &sync_addr, host, count, ob->address_retry_include_sender,
2421 lflags.pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
2424 case 3: lflags.ok = TRUE; /* 2xx & 5xx => OK & progress made */
2425 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2428 case 1: lflags.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2429 if (!lflags.lmtp) completed_address = TRUE; /* can't tell about progress yet */
2430 case 0: /* No 2xx or 5xx, but no probs */
2433 case -1: goto END_OFF; /* Timeout on RCPT */
2434 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
2436 lflags.pending_MAIL = FALSE; /* Dealt with MAIL */
2438 } /* Loop for next address */
2440 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
2441 permanently or temporarily. We should have flushed and synced after the last
2446 address_item *badaddr;
2447 for (badaddr = first_addr; badaddr; badaddr = badaddr->next)
2448 if (badaddr->transport_return != PENDING_OK)
2450 /*XXX could we find a better errno than 0 here? */
2451 set_errno_nohost(addrlist, 0, badaddr->message, FAIL,
2452 testflag(badaddr, af_pass_message));
2458 /* If ok is TRUE, we know we have got at least one good recipient, and must now
2459 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
2460 have a good recipient buffered up if we are pipelining. We don't want to waste
2461 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
2462 are pipelining. The responses are all handled by sync_responses().
2463 If using CHUNKING, do not send a BDAT until we know how big a chunk we want
2466 if ( !(peer_offered & PEER_OFFERED_CHUNKING)
2467 && (lflags.ok || (pipelining_active && !mua_wrapper)))
2469 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
2471 if (count < 0) goto SEND_FAILED;
2472 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
2473 host, count, ob->address_retry_include_sender, lflags.pending_MAIL,
2474 lflags.ok ? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
2476 case 3: lflags.ok = TRUE; /* 2xx & 5xx => OK & progress made */
2477 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2480 case 1: lflags.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2481 if (!lflags.lmtp) completed_address = TRUE; /* can't tell about progress yet */
2482 case 0: break; /* No 2xx or 5xx, but no probs */
2484 case -1: goto END_OFF; /* Timeout on RCPT */
2485 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2487 pipelining_active = FALSE;
2490 /* If there were no good recipients (but otherwise there have been no
2491 problems), just set ok TRUE, since we have handled address-specific errors
2492 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
2493 for handling the SMTP dot-handling protocol, flagging to apply to headers as
2494 well as body. Set the appropriate timeout value to be used for each chunk.
2495 (Haven't been able to make it work using select() for writing yet.) */
2497 if (!(peer_offered & PEER_OFFERED_CHUNKING) && !lflags.ok)
2499 /* Save the first address of the next batch. */
2506 transport_ctx tctx = {
2509 US".", US"..", /* Escaping strings */
2510 topt_use_crlf | topt_escape_headers
2511 | (tblock->body_only ? topt_no_headers : 0)
2512 | (tblock->headers_only ? topt_no_body : 0)
2513 | (tblock->return_path_add ? topt_add_return_path : 0)
2514 | (tblock->delivery_date_add ? topt_add_delivery_date : 0)
2515 | (tblock->envelope_to_add ? topt_add_envelope_to : 0)
2518 /* If using CHUNKING we need a callback from the generic transport
2519 support to us, for the sending of BDAT smtp commands and the reaping
2520 of responses. The callback needs a whole bunch of state so set up
2521 a transport-context structure to be passed around. */
2523 if (peer_offered & PEER_OFFERED_CHUNKING)
2525 tctx.check_string = tctx.escape_string = NULL;
2526 tctx.options |= topt_use_bdat;
2527 tctx.chunk_cb = smtp_chunk_cmd_callback;
2528 tctx.inblock = &inblock;
2529 tctx.outblock = &outblock;
2531 tctx.first_addr = first_addr;
2532 tctx.sync_addr = &sync_addr;
2533 tctx.pending_MAIL = lflags.pending_MAIL;
2534 tctx.pending_BDAT = FALSE;
2535 tctx.good_RCPT = lflags.ok;
2536 tctx.completed_address = &completed_address;
2538 tctx.buffer = buffer;
2541 tctx.options |= topt_end_dot;
2543 /* Save the first address of the next batch. */
2546 /* Responses from CHUNKING commands go in buffer. Otherwise,
2547 there has not been a response. */
2551 sigalrm_seen = FALSE;
2552 transport_write_timeout = ob->data_timeout;
2553 smtp_command = US"sending data block"; /* For error messages */
2554 DEBUG(D_transport|D_v)
2555 if (peer_offered & PEER_OFFERED_CHUNKING)
2556 debug_printf(" will write message using CHUNKING\n");
2558 debug_printf(" SMTP>> writing message and terminating \".\"\n");
2559 transport_count = 0;
2561 #ifndef DISABLE_DKIM
2562 lflags.ok = dkim_transport_write_message(inblock.sock, &tctx, &ob->dkim);
2564 lflags.ok = transport_write_message(inblock.sock, &tctx, 0);
2567 /* transport_write_message() uses write() because it is called from other
2568 places to write to non-sockets. This means that under some OS (e.g. Solaris)
2569 it can exit with "Broken pipe" as its error. This really means that the
2570 socket got closed at the far end. */
2572 transport_write_timeout = 0; /* for subsequent transports */
2574 /* Failure can either be some kind of I/O disaster (including timeout),
2575 or the failure of a transport filter or the expansion of added headers.
2576 Or, when CHUNKING, it can be a protocol-detected failure. */
2579 goto RESPONSE_FAILED;
2581 /* We used to send the terminating "." explicitly here, but because of
2582 buffering effects at both ends of TCP/IP connections, you don't gain
2583 anything by keeping it separate, so it might as well go in the final
2584 data buffer for efficiency. This is now done by setting the topt_end_dot
2587 smtp_command = US"end of data";
2589 if (peer_offered & PEER_OFFERED_CHUNKING && tctx.cmd_count > 1)
2591 /* Reap any outstanding MAIL & RCPT commands, but not a DATA-go-ahead */
2592 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
2593 host, tctx.cmd_count-1, ob->address_retry_include_sender,
2594 lflags.pending_MAIL, 0,
2595 &inblock, ob->command_timeout, buffer, sizeof(buffer)))
2597 case 3: lflags.ok = TRUE; /* 2xx & 5xx => OK & progress made */
2598 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2601 case 1: lflags.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2602 if (!lflags.lmtp) completed_address = TRUE; /* can't tell about progress yet */
2603 case 0: break; /* No 2xx or 5xx, but no probs */
2605 case -1: goto END_OFF; /* Timeout on RCPT */
2606 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2610 #ifndef DISABLE_PRDR
2611 /* For PRDR we optionally get a partial-responses warning
2612 * followed by the individual responses, before going on with
2613 * the overall response. If we don't get the warning then deal
2614 * with per non-PRDR. */
2615 if(lflags.prdr_active)
2617 lflags.ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '3',
2619 if (!lflags.ok && errno == 0) switch(buffer[0])
2621 case '2': lflags.prdr_active = FALSE;
2624 case '4': errno = ERRNO_DATA4XX;
2625 addrlist->more_errno |=
2626 ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2633 /* For non-PRDR SMTP, we now read a single response that applies to the
2634 whole message. If it is OK, then all the addresses have been delivered. */
2638 lflags.ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2640 if (!lflags.ok && errno == 0 && buffer[0] == '4')
2642 errno = ERRNO_DATA4XX;
2643 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2647 /* For LMTP, we get back a response for every RCPT command that we sent;
2648 some may be accepted and some rejected. For those that get a response, their
2649 status is fixed; any that are accepted have been handed over, even if later
2650 responses crash - at least, that's how I read RFC 2033.
2652 If all went well, mark the recipient addresses as completed, record which
2653 host/IPaddress they were delivered to, and cut out RSET when sending another
2654 message down the same channel. Write the completed addresses to the journal
2655 now so that they are recorded in case there is a crash of hardware or
2656 software before the spool gets updated. Also record the final SMTP
2657 confirmation if needed (for SMTP only). */
2662 int delivery_time = (int)(time(NULL) - start_delivery_time);
2664 uschar *conf = NULL;
2666 lflags.send_rset = FALSE;
2667 pipelining_active = FALSE;
2669 /* Set up confirmation if needed - applies only to SMTP */
2672 #ifdef DISABLE_EVENT
2673 LOGGING(smtp_confirmation) &&
2678 const uschar *s = string_printing(buffer);
2679 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
2680 conf = (s == buffer)? (uschar *)string_copy(s) : US s;
2683 /* Process all transported addresses - for LMTP or PRDR, read a status for
2686 for (addr = addrlist; addr != first_addr; addr = addr->next)
2688 if (addr->transport_return != PENDING_OK) continue;
2690 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
2691 remaining addresses. Otherwise, it's a return code for just the one
2692 address. For temporary errors, add a retry item for the address so that
2693 it doesn't get tried again too soon. */
2695 #ifndef DISABLE_PRDR
2696 if (lflags.lmtp || lflags.prdr_active)
2701 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2704 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
2705 addr->message = string_sprintf(
2706 #ifndef DISABLE_PRDR
2707 "%s error after %s: %s", lflags.prdr_active ? "PRDR":"LMTP",
2709 "LMTP error after %s: %s",
2711 big_buffer, string_printing(buffer));
2712 setflag(addr, af_pass_message); /* Allow message to go to user */
2713 if (buffer[0] == '5')
2714 addr->transport_return = FAIL;
2717 errno = ERRNO_DATA4XX;
2718 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2719 addr->transport_return = DEFER;
2720 #ifndef DISABLE_PRDR
2721 if (!lflags.prdr_active)
2723 retry_add_item(addr, addr->address_retry_key, 0);
2727 completed_address = TRUE; /* NOW we can set this flag */
2728 if (LOGGING(smtp_confirmation))
2730 const uschar *s = string_printing(buffer);
2731 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
2732 conf = (s == buffer)? (uschar *)string_copy(s) : US s;
2736 /* SMTP, or success return from LMTP for this address. Pass back the
2737 actual host that was used. */
2739 addr->transport_return = OK;
2740 addr->more_errno = delivery_time;
2741 addr->host_used = host;
2742 addr->special_action = flag;
2743 addr->message = conf;
2744 #ifndef DISABLE_PRDR
2745 if (lflags.prdr_active) addr->flags |= af_prdr_used;
2747 if (peer_offered & PEER_OFFERED_CHUNKING) addr->flags |= af_chunking_used;
2750 #ifndef DISABLE_PRDR
2751 if (!lflags.prdr_active)
2754 /* Update the journal. For homonymic addresses, use the base address plus
2755 the transport name. See lots of comments in deliver.c about the reasons
2756 for the complications when homonyms are involved. Just carry on after
2757 write error, as it may prove possible to update the spool file later. */
2759 if (testflag(addr, af_homonym))
2760 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2762 sprintf(CS buffer, "%.500s\n", addr->unique);
2764 DEBUG(D_deliver) debug_printf("journalling %s\n", buffer);
2765 len = Ustrlen(CS buffer);
2766 if (write(journal_fd, buffer, len) != len)
2767 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2768 "%s: %s", buffer, strerror(errno));
2772 #ifndef DISABLE_PRDR
2773 if (lflags.prdr_active)
2775 /* PRDR - get the final, overall response. For any non-success
2776 upgrade all the address statuses. */
2777 lflags.ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2781 if(errno == 0 && buffer[0] == '4')
2783 errno = ERRNO_DATA4XX;
2784 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2786 for (addr = addrlist; addr != first_addr; addr = addr->next)
2787 if (buffer[0] == '5' || addr->transport_return == OK)
2788 addr->transport_return = PENDING_OK; /* allow set_errno action */
2789 goto RESPONSE_FAILED;
2792 /* Update the journal, or setup retry. */
2793 for (addr = addrlist; addr != first_addr; addr = addr->next)
2794 if (addr->transport_return == OK)
2796 if (testflag(addr, af_homonym))
2797 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2799 sprintf(CS buffer, "%.500s\n", addr->unique);
2801 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s\n", buffer);
2802 len = Ustrlen(CS buffer);
2803 if (write(journal_fd, buffer, len) != len)
2804 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2805 "%s: %s", buffer, strerror(errno));
2807 else if (addr->transport_return == DEFER)
2808 retry_add_item(addr, addr->address_retry_key, -2);
2812 /* Ensure the journal file is pushed out to disk. */
2814 if (EXIMfsync(journal_fd) < 0)
2815 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
2821 /* Handle general (not specific to one address) failures here. The value of ok
2822 is used to skip over this code on the falling through case. A timeout causes a
2823 deferral. Other errors may defer or fail according to the response code, and
2824 may set up a special errno value, e.g. after connection chopped, which is
2825 assumed if errno == 0 and there is no text in the buffer. If control reaches
2826 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
2827 the problem is not related to this specific message. */
2832 uschar * set_message;
2838 lflags.send_quit = check_response(host, &save_errno, addrlist->more_errno,
2839 buffer, &code, &message, &pass_message);
2847 message = US string_sprintf("send() to %s [%s] failed: %s",
2848 host->name, host->address, strerror(save_errno));
2849 lflags.send_quit = FALSE;
2853 /* This label is jumped to directly when a TLS negotiation has failed,
2854 or was not done for a host for which it is required. Values will be set
2855 in message and save_errno, and setting_up will always be true. Treat as
2856 a temporary error. */
2863 /* If the failure happened while setting up the call, see if the failure was
2864 a 5xx response (this will either be on connection, or following HELO - a 5xx
2865 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
2866 never going to accept them. For other errors during setting up (timeouts or
2867 whatever), defer all addresses, and yield DEFER, so that the host is not
2868 tried again for a while. */
2871 lflags.ok = FALSE; /* For when reached by GOTO */
2872 set_message = message;
2874 if (lflags.setting_up)
2878 yield = set_rc = DEFER;
2880 /* We want to handle timeouts after MAIL or "." and loss of connection after
2881 "." specially. They can indicate a problem with the sender address or with
2882 the contents of the message rather than a real error on the connection. These
2883 cases are treated in the same way as a 4xx response. This next bit of code
2884 does the classification. */
2893 case ERRNO_UTF8_FWD:
2900 message_error = TRUE;
2904 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
2905 Ustrncmp(smtp_command,"end ",4) == 0;
2908 case ERRNO_SMTPCLOSED:
2909 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
2913 message_error = FALSE;
2917 /* Handle the cases that are treated as message errors. These are:
2919 (a) negative response or timeout after MAIL
2920 (b) negative response after DATA
2921 (c) negative response or timeout or dropped connection after "."
2922 (d) utf8 support required and not offered
2924 It won't be a negative response or timeout after RCPT, as that is dealt
2925 with separately above. The action in all cases is to set an appropriate
2926 error code for all the addresses, but to leave yield set to OK because the
2927 host itself has not failed. Of course, it might in practice have failed
2928 when we've had a timeout, but if so, we'll discover that at the next
2929 delivery attempt. For a temporary error, set the message_defer flag, and
2930 write to the logs for information if this is not the last host. The error
2931 for the last host will be logged as part of the address's log line. */
2935 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
2937 /* If there's an errno, the message contains just the identity of
2942 else /* Anything other than 5 is treated as temporary */
2946 message = US string_sprintf("%s: %s", message, strerror(save_errno));
2947 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
2948 msglog_line(host, message);
2949 *message_defer = TRUE;
2953 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
2954 ".", or some other transportation error. We defer all addresses and yield
2955 DEFER, except for the case of failed add_headers expansion, or a transport
2956 filter failure, when the yield should be ERROR, to stop it trying other
2962 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
2963 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
2967 set_errno(addrlist, save_errno, set_message, set_rc, pass_message, host
2968 #ifdef EXPERIMENTAL_DSN_INFO
2969 , smtp_greeting, helo_response
2975 /* If all has gone well, send_quit will be set TRUE, implying we can end the
2976 SMTP session tidily. However, if there were too many addresses to send in one
2977 message (indicated by first_addr being non-NULL) we want to carry on with the
2978 rest of them. Also, it is desirable to send more than one message down the SMTP
2979 connection if there are several waiting, provided we haven't already sent so
2980 many as to hit the configured limit. The function transport_check_waiting looks
2981 for a waiting message and returns its id. Then transport_pass_socket tries to
2982 set up a continued delivery by passing the socket on to another process. The
2983 variable send_rset is FALSE if a message has just been successfully transfered.
2985 If we are already sending down a continued channel, there may be further
2986 addresses not yet delivered that are aimed at the same host, but which have not
2987 been passed in this run of the transport. In this case, continue_more will be
2988 true, and all we should do is send RSET if necessary, and return, leaving the
2991 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
2992 do not want to continue with other messages down the same channel, because that
2993 can lead to looping between two or more messages, all with the same,
2994 temporarily failing address(es). [The retry information isn't updated yet, so
2995 new processes keep on trying.] We probably also don't want to try more of this
2996 message's addresses either.
2998 If we have started a TLS session, we have to end it before passing the
2999 connection to a new process. However, not all servers can handle this (Exim
3000 can), so we do not pass such a connection on if the host matches
3001 hosts_nopass_tls. */
3004 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
3005 "yield=%d first_address is %sNULL\n", lflags.ok, lflags.send_quit,
3006 lflags.send_rset, continue_more, yield, first_addr ? "not " : "");
3008 if (completed_address && lflags.ok && lflags.send_quit)
3011 smtp_compare_t t_compare;
3013 t_compare.tblock = tblock;
3014 t_compare.current_sender_address = sender_address;
3016 if ( first_addr != NULL
3018 || ( ( tls_out.active < 0
3019 || verify_check_given_host(&ob->hosts_nopass_tls, host) != OK
3022 transport_check_waiting(tblock->name, host->name,
3023 tblock->connection_max_messages, new_message_id, &more,
3024 (oicf)smtp_are_same_identities, (void*)&t_compare)
3030 if (lflags.send_rset)
3032 if (! (lflags.ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
3034 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
3035 host->address, strerror(save_errno));
3036 lflags.send_quit = FALSE;
3038 else if (! (lflags.ok = smtp_read_response(&inblock, buffer,
3039 sizeof(buffer), '2', ob->command_timeout)))
3042 lflags.send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
3044 if (!lflags.send_quit)
3046 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
3047 host->name, host->address, msg);
3052 /* Either RSET was not needed, or it succeeded */
3056 if (first_addr != NULL) /* More addresses still to be sent */
3057 { /* in this run of the transport */
3058 continue_sequence++; /* Causes * in logging */
3061 if (continue_more) return yield; /* More addresses for another run */
3063 /* Pass the socket to a new Exim process. Before doing so, we must shut
3064 down TLS. Not all MTAs allow for the continuation of the SMTP session
3065 when TLS is shut down. We test for this by sending a new EHLO. If we
3066 don't get a good response, we don't attempt to pass the socket on. */
3069 if (tls_out.active >= 0)
3071 tls_close(FALSE, TRUE);
3072 smtp_peer_options = smtp_peer_options_wrap;
3076 lflags.ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
3077 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
3078 ob->command_timeout);
3082 /* If the socket is successfully passed, we musn't send QUIT (or
3083 indeed anything!) from here. */
3085 /*XXX DSN_INFO: assume likely to do new HELO; but for greet we'll want to
3086 propagate it from the initial
3088 if (lflags.ok && transport_pass_socket(tblock->name, host->name,
3089 host->address, new_message_id, inblock.sock))
3090 lflags.send_quit = FALSE;
3093 /* If RSET failed and there are addresses left, they get deferred. */
3095 else set_errno(first_addr, errno, msg, DEFER, FALSE, host
3096 #ifdef EXPERIMENTAL_DSN_INFO
3097 , smtp_greeting, helo_response
3103 /* End off tidily with QUIT unless the connection has died or the socket has
3104 been passed to another process. There has been discussion on the net about what
3105 to do after sending QUIT. The wording of the RFC suggests that it is necessary
3106 to wait for a response, but on the other hand, there isn't anything one can do
3107 with an error response, other than log it. Exim used to do that. However,
3108 further discussion suggested that it is positively advantageous not to wait for
3109 the response, but to close the session immediately. This is supposed to move
3110 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
3111 load from the server. (Hosts that are both servers and clients may not see much
3112 difference, of course.) Further discussion indicated that this was safe to do
3113 on Unix systems which have decent implementations of TCP/IP that leave the
3114 connection around for a while (TIME_WAIT) after the application has gone away.
3115 This enables the response sent by the server to be properly ACKed rather than
3116 timed out, as can happen on broken TCP/IP implementations on other OS.
3118 This change is being made on 31-Jul-98. After over a year of trouble-free
3119 operation, the old commented-out code was removed on 17-Sep-99. */
3122 if (lflags.send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
3127 tls_close(FALSE, TRUE);
3130 /* Close the socket, and return the appropriate value, first setting
3131 works because the NULL setting is passed back to the calling process, and
3132 remote_max_parallel is forced to 1 when delivering over an existing connection,
3134 If all went well and continue_more is set, we shouldn't actually get here if
3135 there are further addresses, as the return above will be taken. However,
3136 writing RSET might have failed, or there may be other addresses whose hosts are
3137 specified in the transports, and therefore not visible at top level, in which
3138 case continue_more won't get set. */
3140 HDEBUG(D_transport|D_acl|D_v) debug_printf(" SMTP(close)>>\n");
3141 (void)close(inblock.sock);
3143 #ifndef DISABLE_EVENT
3144 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
3147 continue_transport = NULL;
3148 continue_hostname = NULL;
3155 /*************************************************
3156 * Closedown entry point *
3157 *************************************************/
3159 /* This function is called when exim is passed an open smtp channel
3160 from another incarnation, but the message which it has been asked
3161 to deliver no longer exists. The channel is on stdin.
3163 We might do fancy things like looking for another message to send down
3164 the channel, but if the one we sought has gone, it has probably been
3165 delivered by some other process that itself will seek further messages,
3166 so just close down our connection.
3168 Argument: pointer to the transport instance block
3173 smtp_transport_closedown(transport_instance *tblock)
3175 smtp_transport_options_block *ob =
3176 (smtp_transport_options_block *)(tblock->options_block);
3177 smtp_inblock inblock;
3178 smtp_outblock outblock;
3180 uschar inbuffer[4096];
3181 uschar outbuffer[16];
3183 inblock.sock = fileno(stdin);
3184 inblock.buffer = inbuffer;
3185 inblock.buffersize = sizeof(inbuffer);
3186 inblock.ptr = inbuffer;
3187 inblock.ptrend = inbuffer;
3189 outblock.sock = inblock.sock;
3190 outblock.buffersize = sizeof(outbuffer);
3191 outblock.buffer = outbuffer;
3192 outblock.ptr = outbuffer;
3193 outblock.cmd_count = 0;
3194 outblock.authenticating = FALSE;
3196 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
3197 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
3198 ob->command_timeout);
3199 (void)close(inblock.sock);
3204 /*************************************************
3205 * Prepare addresses for delivery *
3206 *************************************************/
3208 /* This function is called to flush out error settings from previous delivery
3209 attempts to other hosts. It also records whether we got here via an MX record
3210 or not in the more_errno field of the address. We are interested only in
3211 addresses that are still marked DEFER - others may have got delivered to a
3212 previously considered IP address. Set their status to PENDING_DEFER to indicate
3213 which ones are relevant this time.
3216 addrlist the list of addresses
3217 host the host we are delivering to
3219 Returns: the first address for this delivery
3222 static address_item *
3223 prepare_addresses(address_item *addrlist, host_item *host)
3225 address_item *first_addr = NULL;
3227 for (addr = addrlist; addr; addr = addr->next)
3228 if (addr->transport_return == DEFER)
3230 if (!first_addr) first_addr = addr;
3231 addr->transport_return = PENDING_DEFER;
3232 addr->basic_errno = 0;
3233 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
3234 addr->message = NULL;
3236 addr->cipher = NULL;
3237 addr->ourcert = NULL;
3238 addr->peercert = NULL;
3239 addr->peerdn = NULL;
3240 addr->ocsp = OCSP_NOT_REQ;
3242 #ifdef EXPERIMENTAL_DSN_INFO
3243 addr->smtp_greeting = NULL;
3244 addr->helo_response = NULL;
3252 /*************************************************
3253 * Main entry point *
3254 *************************************************/
3256 /* See local README for interface details. As this is a remote transport, it is
3257 given a chain of addresses to be delivered in one connection, if possible. It
3258 always returns TRUE, indicating that each address has its own independent
3259 status set, except if there is a setting up problem, in which case it returns
3263 smtp_transport_entry(
3264 transport_instance *tblock, /* data for this instantiation */
3265 address_item *addrlist) /* addresses we are working on */
3269 int hosts_defer = 0;
3271 int hosts_looked_up = 0;
3272 int hosts_retry = 0;
3273 int hosts_serial = 0;
3274 int hosts_total = 0;
3275 int total_hosts_tried = 0;
3277 BOOL expired = TRUE;
3278 uschar *expanded_hosts = NULL;
3280 uschar *tid = string_sprintf("%s transport", tblock->name);
3281 smtp_transport_options_block *ob =
3282 (smtp_transport_options_block *)(tblock->options_block);
3283 host_item *hostlist = addrlist->host_list;
3284 host_item *host = NULL;
3288 debug_printf("%s transport entered\n", tblock->name);
3289 for (addr = addrlist; addr; addr = addr->next)
3290 debug_printf(" %s\n", addr->address);
3293 debug_printf("hostlist:\n");
3294 for (host = hostlist; host; host = host->next)
3295 debug_printf(" %s:%d\n", host->name, host->port);
3297 if (continue_hostname) debug_printf("already connected to %s [%s]\n",
3298 continue_hostname, continue_host_address);
3301 /* Set the flag requesting that these hosts be added to the waiting
3302 database if the delivery fails temporarily or if we are running with
3303 queue_smtp or a 2-stage queue run. This gets unset for certain
3304 kinds of error, typically those that are specific to the message. */
3306 update_waiting = TRUE;
3308 /* If a host list is not defined for the addresses - they must all have the
3309 same one in order to be passed to a single transport - or if the transport has
3310 a host list with hosts_override set, use the host list supplied with the
3311 transport. It is an error for this not to exist. */
3313 if (!hostlist || (ob->hosts_override && ob->hosts))
3317 addrlist->message = string_sprintf("%s transport called with no hosts set",
3319 addrlist->transport_return = PANIC;
3320 return FALSE; /* Only top address has status */
3323 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
3326 /* If the transport's host list contains no '$' characters, and we are not
3327 randomizing, it is fixed and therefore a chain of hosts can be built once
3328 and for all, and remembered for subsequent use by other calls to this
3329 transport. If, on the other hand, the host list does contain '$', or we are
3330 randomizing its order, we have to rebuild it each time. In the fixed case,
3331 as the hosts string will never be used again, it doesn't matter that we
3332 replace all the : characters with zeros. */
3336 uschar *s = ob->hosts;
3338 if (Ustrchr(s, '$') != NULL)
3340 if (!(expanded_hosts = expand_string(s)))
3342 addrlist->message = string_sprintf("failed to expand list of hosts "
3343 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
3344 addrlist->transport_return = search_find_defer ? DEFER : PANIC;
3345 return FALSE; /* Only top address has status */
3347 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
3348 "\"%s\"\n", s, expanded_hosts);
3352 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
3354 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
3356 /* Check that the expansion yielded something useful. */
3360 string_sprintf("%s transport has empty hosts setting", tblock->name);
3361 addrlist->transport_return = PANIC;
3362 return FALSE; /* Only top address has status */
3365 /* If there was no expansion of hosts, save the host list for
3368 if (!expanded_hosts) ob->hostlist = hostlist;
3371 /* This is not the first time this transport has been run in this delivery;
3372 the host list was built previously. */
3375 hostlist = ob->hostlist;
3378 /* The host list was supplied with the address. If hosts_randomize is set, we
3379 must sort it into a random order if it did not come from MX records and has not
3380 already been randomized (but don't bother if continuing down an existing
3383 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continue_hostname)
3385 host_item *newlist = NULL;
3388 host_item *h = hostlist;
3389 hostlist = hostlist->next;
3391 h->sort_key = random_number(100);
3398 else if (h->sort_key < newlist->sort_key)
3405 host_item *hh = newlist;
3408 if (h->sort_key < hh->next->sort_key) break;
3416 hostlist = addrlist->host_list = newlist;
3419 /* Sort out the default port. */
3421 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
3423 /* For each host-plus-IP-address on the list:
3425 . If this is a continued delivery and the host isn't the one with the
3426 current connection, skip.
3428 . If the status is unusable (i.e. previously failed or retry checked), skip.
3430 . If no IP address set, get the address, either by turning the name into
3431 an address, calling gethostbyname if gethostbyname is on, or by calling
3432 the DNS. The DNS may yield multiple addresses, in which case insert the
3433 extra ones into the list.
3435 . Get the retry data if not previously obtained for this address and set the
3436 field which remembers the state of this address. Skip if the retry time is
3437 not reached. If not, remember whether retry data was found. The retry string
3438 contains both the name and the IP address.
3440 . Scan the list of addresses and mark those whose status is DEFER as
3441 PENDING_DEFER. These are the only ones that will be processed in this cycle
3444 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
3445 Some addresses may be successfully delivered, others may fail, and yet
3446 others may get temporary errors and so get marked DEFER.
3448 . The return from the delivery attempt is OK if a connection was made and a
3449 valid SMTP dialogue was completed. Otherwise it is DEFER.
3451 . If OK, add a "remove" retry item for this host/IPaddress, if any.
3453 . If fail to connect, or other defer state, add a retry item.
3455 . If there are any addresses whose status is still DEFER, carry on to the
3456 next host/IPaddress, unless we have tried the number of hosts given
3457 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
3458 there is some fancy logic for hosts_max_try that means its limit can be
3459 overstepped in some circumstances.
3461 If we get to the end of the list, all hosts have deferred at least one address,
3462 or not reached their retry times. If delay_after_cutoff is unset, it requests a
3463 delivery attempt to those hosts whose last try was before the arrival time of
3464 the current message. To cope with this, we have to go round the loop a second
3465 time. After that, set the status and error data for any addresses that haven't
3466 had it set already. */
3468 for (cutoff_retry = 0;
3469 expired && cutoff_retry < (ob->delay_after_cutoff ? 1 : 2);
3472 host_item *nexthost = NULL;
3473 int unexpired_hosts_tried = 0;
3475 for (host = hostlist;
3477 && unexpired_hosts_tried < ob->hosts_max_try
3478 && total_hosts_tried < ob->hosts_max_try_hardlimit;
3484 BOOL host_is_expired = FALSE;
3485 BOOL message_defer = FALSE;
3486 BOOL some_deferred = FALSE;
3487 address_item *first_addr = NULL;
3488 uschar *interface = NULL;
3489 uschar *retry_host_key = NULL;
3490 uschar *retry_message_key = NULL;
3491 uschar *serialize_key = NULL;
3493 /* Default next host is next host. :-) But this can vary if the
3494 hosts_max_try limit is hit (see below). It may also be reset if a host
3495 address is looked up here (in case the host was multihomed). */
3497 nexthost = host->next;
3499 /* If the address hasn't yet been obtained from the host name, look it up
3500 now, unless the host is already marked as unusable. If it is marked as
3501 unusable, it means that the router was unable to find its IP address (in
3502 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
3503 the lookup failed last time. We don't get this far if *all* MX records
3504 point to non-existent hosts; that is treated as a hard error.
3506 We can just skip this host entirely. When the hosts came from the router,
3507 the address will timeout based on the other host(s); when the address is
3508 looked up below, there is an explicit retry record added.
3510 Note that we mustn't skip unusable hosts if the address is not unset; they
3511 may be needed as expired hosts on the 2nd time round the cutoff loop. */
3515 int new_port, flags;
3518 if (host->status >= hstatus_unusable)
3520 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
3525 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
3527 /* The host name is permitted to have an attached port. Find it, and
3528 strip it from the name. Just remember it for now. */
3530 new_port = host_item_get_port(host);
3532 /* Count hosts looked up */
3536 /* Find by name if so configured, or if it's an IP address. We don't
3537 just copy the IP address, because we need the test-for-local to happen. */
3539 flags = HOST_FIND_BY_A;
3540 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
3541 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
3543 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
3544 rc = host_find_byname(host, NULL, flags, NULL, TRUE);
3546 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
3547 &ob->dnssec, /* domains for request/require */
3550 /* Update the host (and any additional blocks, resulting from
3551 multihoming) with a host-specific port, if any. */
3553 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
3555 /* Failure to find the host at this time (usually DNS temporary failure)
3556 is really a kind of routing failure rather than a transport failure.
3557 Therefore we add a retry item of the routing kind, not to stop us trying
3558 to look this name up here again, but to ensure the address gets timed
3559 out if the failures go on long enough. A complete failure at this point
3560 commonly points to a configuration error, but the best action is still
3561 to carry on for the next host. */
3563 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
3565 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
3567 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
3568 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
3569 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
3570 host->status = hstatus_unusable;
3572 for (addr = addrlist; addr; addr = addr->next)
3574 if (addr->transport_return != DEFER) continue;
3575 addr->basic_errno = ERRNO_UNKNOWNHOST;
3577 string_sprintf("failed to lookup IP address for %s", host->name);
3582 /* If the host is actually the local host, we may have a problem, or
3583 there may be some cunning configuration going on. In the problem case,
3584 log things and give up. The default transport status is already DEFER. */
3586 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
3588 for (addr = addrlist; addr; addr = addr->next)
3590 addr->basic_errno = 0;
3591 addr->message = string_sprintf("%s transport found host %s to be "
3592 "local", tblock->name, host->name);
3596 } /* End of block for IP address lookup */
3598 /* If this is a continued delivery, we are interested only in the host
3599 which matches the name of the existing open channel. The check is put
3600 here after the local host lookup, in case the name gets expanded as a
3601 result of the lookup. Set expired FALSE, to save the outer loop executing
3604 if ( continue_hostname
3605 && ( Ustrcmp(continue_hostname, host->name) != 0
3606 || Ustrcmp(continue_host_address, host->address) != 0
3610 continue; /* With next host */
3613 /* Reset the default next host in case a multihomed host whose addresses
3614 are not looked up till just above added to the host list. */
3616 nexthost = host->next;
3618 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
3619 domain is in queue_smtp_domains, we don't actually want to attempt any
3620 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
3621 there is a lookup defer in queue_smtp_domains, proceed as if the domain
3622 were not in it. We don't want to hold up all SMTP deliveries! Except when
3623 doing a two-stage queue run, don't do this if forcing. */
3625 if ((!deliver_force || queue_2stage) && (queue_smtp ||
3626 match_isinlist(addrlist->domain,
3627 (const uschar **)&queue_smtp_domains, 0,
3628 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
3631 for (addr = addrlist; addr; addr = addr->next)
3632 if (addr->transport_return == DEFER)
3633 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
3634 continue; /* With next host */
3637 /* Count hosts being considered - purely for an intelligent comment
3638 if none are usable. */
3642 /* Set $host and $host address now in case they are needed for the
3643 interface expansion or the serialize_hosts check; they remain set if an
3644 actual delivery happens. */
3646 deliver_host = host->name;
3647 deliver_host_address = host->address;
3648 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
3649 : host->dnssec == DS_NO ? US"no"
3652 /* Set up a string for adding to the retry key if the port number is not
3653 the standard SMTP port. A host may have its own port setting that overrides
3656 pistring = string_sprintf(":%d", host->port == PORT_NONE
3657 ? port : host->port);
3658 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
3660 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
3661 string is set, even if constant (as different transports can have different
3662 constant settings), we must add it to the key that is used for retries,
3663 because connections to the same host from a different interface should be
3664 treated separately. */
3666 host_af = Ustrchr(host->address, ':') == NULL ? AF_INET : AF_INET6;
3667 if ((rs = ob->interface) && *rs)
3669 if (!smtp_get_interface(rs, host_af, addrlist, &interface, tid))
3671 pistring = string_sprintf("%s/%s", pistring, interface);
3674 /* The first time round the outer loop, check the status of the host by
3675 inspecting the retry data. The second time round, we are interested only
3676 in expired hosts that haven't been tried since this message arrived. */
3678 if (cutoff_retry == 0)
3681 /* Ensure the status of the address is set by checking retry data if
3682 necessary. There may be host-specific retry data (applicable to all
3683 messages) and also data for retries of a specific message at this host.
3684 If either of these retry records are actually read, the keys used are
3685 returned to save recomputing them later. */
3687 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3688 US"retry_include_ip_address", ob->retry_include_ip_address,
3689 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3690 continue; /* with next host */
3692 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
3693 incl_ip, &retry_host_key, &retry_message_key);
3695 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
3696 (host->address == NULL)? US"" : host->address, pistring,
3697 (host->status == hstatus_usable)? "usable" :
3698 (host->status == hstatus_unusable)? "unusable" :
3699 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
3701 /* Skip this address if not usable at this time, noting if it wasn't
3702 actually expired, both locally and in the address. */
3704 switch (host->status)
3706 case hstatus_unusable:
3708 setflag(addrlist, af_retry_skipped);
3711 case hstatus_unusable_expired:
3714 case hwhy_retry: hosts_retry++; break;
3715 case hwhy_failed: hosts_fail++; break;
3716 case hwhy_deferred: hosts_defer++; break;
3719 /* If there was a retry message key, implying that previously there
3720 was a message-specific defer, we don't want to update the list of
3721 messages waiting for these hosts. */
3723 if (retry_message_key) update_waiting = FALSE;
3724 continue; /* With the next host or IP address */
3728 /* Second time round the loop: if the address is set but expired, and
3729 the message is newer than the last try, let it through. */
3734 || host->status != hstatus_unusable_expired
3735 || host->last_try > received_time)
3737 DEBUG(D_transport) debug_printf("trying expired host %s [%s]%s\n",
3738 host->name, host->address, pistring);
3739 host_is_expired = TRUE;
3742 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
3743 it remains TRUE only if all hosts are expired and none are actually tried.
3748 /* If this host is listed as one to which access must be serialized,
3749 see if another Exim process has a connection to it, and if so, skip
3750 this host. If not, update the database to record our connection to it
3751 and remember this for later deletion. Do not do any of this if we are
3752 sending the message down a pre-existing connection. */
3754 if ( !continue_hostname
3755 && verify_check_given_host(&ob->serialize_hosts, host) == OK)
3757 serialize_key = string_sprintf("host-serialize-%s", host->name);
3758 if (!enq_start(serialize_key, 1))
3761 debug_printf("skipping host %s because another Exim process "
3762 "is connected to it\n", host->name);
3768 /* OK, we have an IP address that is not waiting for its retry time to
3769 arrive (it might be expired) OR (second time round the loop) we have an
3770 expired host that hasn't been tried since the message arrived. Have a go
3771 at delivering the message to it. First prepare the addresses by flushing
3772 out the result of previous attempts, and finding the first address that
3773 is still to be delivered. */
3775 first_addr = prepare_addresses(addrlist, host);
3777 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
3778 message_id, host->name, host->address, addrlist->address,
3779 addrlist->next ? ", ..." : "");
3781 set_process_info("delivering %s to %s [%s] (%s%s)",
3782 message_id, host->name, host->address, addrlist->address,
3783 addrlist->next ? ", ..." : "");
3785 /* This is not for real; don't do the delivery. If there are
3786 any remaining hosts, list them. */
3791 set_errno_nohost(addrlist, 0, NULL, OK, FALSE);
3792 for (addr = addrlist; addr; addr = addr->next)
3794 addr->host_used = host;
3795 addr->special_action = '*';
3796 addr->message = US"delivery bypassed by -N option";
3800 debug_printf("*** delivery by %s transport bypassed by -N option\n"
3801 "*** host and remaining hosts:\n", tblock->name);
3802 for (host2 = host; host2; host2 = host2->next)
3803 debug_printf(" %s [%s]\n", host2->name,
3804 host2->address ? host2->address : US"unset");
3809 /* This is for real. If the host is expired, we don't count it for
3810 hosts_max_retry. This ensures that all hosts must expire before an address
3811 is timed out, unless hosts_max_try_hardlimit (which protects against
3812 lunatic DNS configurations) is reached.
3814 If the host is not expired and we are about to hit the hosts_max_retry
3815 limit, check to see if there is a subsequent hosts with a different MX
3816 value. If so, make that the next host, and don't count this one. This is a
3817 heuristic to make sure that different MXs do get tried. With a normal kind
3818 of retry rule, they would get tried anyway when the earlier hosts were
3819 delayed, but if the domain has a "retry every time" type of rule - as is
3820 often used for the the very large ISPs, that won't happen. */
3825 /* Make a copy of the host if it is local to this invocation
3826 of the transport. */
3830 thost = store_get(sizeof(host_item));
3832 thost->name = string_copy(host->name);
3833 thost->address = string_copy(host->address);
3838 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
3842 debug_printf("hosts_max_try limit reached with this host\n");
3843 for (h = host; h; h = h->next) if (h->mx != host->mx)
3846 unexpired_hosts_tried--;
3847 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
3848 "and will be tried\n");
3853 /* Attempt the delivery. */
3855 total_hosts_tried++;
3856 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
3857 &message_defer, FALSE);
3860 OK => connection made, each address contains its result;
3861 message_defer is set for message-specific defers (when all
3862 recipients are marked defer)
3863 DEFER => there was a non-message-specific delivery problem;
3864 ERROR => there was a problem setting up the arguments for a filter,
3865 or there was a problem with expanding added headers
3868 /* If the result is not OK, there was a non-message-specific problem.
3869 If the result is DEFER, we need to write to the logs saying what happened
3870 for this particular host, except in the case of authentication and TLS
3871 failures, where the log has already been written. If all hosts defer a
3872 general message is written at the end. */
3874 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL
3875 && first_addr->basic_errno != ERRNO_TLSFAILURE)
3876 write_logs(first_addr, host);
3878 #ifndef DISABLE_EVENT
3880 deferred_event_raise(first_addr, host);
3883 /* If STARTTLS was accepted, but there was a failure in setting up the
3884 TLS session (usually a certificate screwup), and the host is not in
3885 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
3886 TLS forcibly turned off. We have to start from scratch with a new SMTP
3887 connection. That's why the retry is done from here, not from within
3888 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
3889 session, so the in-clear transmission after those errors, if permitted,
3890 happens inside smtp_deliver().] */
3894 && first_addr->basic_errno == ERRNO_TLSFAILURE
3895 && ob->tls_tempfail_tryclear
3896 && verify_check_given_host(&ob->hosts_require_tls, host) != OK
3899 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
3900 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
3901 first_addr = prepare_addresses(addrlist, host);
3902 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
3903 &message_defer, TRUE);
3904 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
3905 write_logs(first_addr, host);
3906 # ifndef DISABLE_EVENT
3908 deferred_event_raise(first_addr, host);
3911 #endif /*SUPPORT_TLS*/
3914 /* Delivery attempt finished */
3916 rs = rc == OK ? US"OK"
3917 : rc == DEFER ? US"DEFER"
3918 : rc == ERROR ? US"ERROR"
3921 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
3922 message_id, host->name, host->address, addrlist->address,
3923 addrlist->next ? " (& others)" : "", rs);
3925 /* Release serialization if set up */
3927 if (serialize_key) enq_end(serialize_key);
3929 /* If the result is DEFER, or if a host retry record is known to exist, we
3930 need to add an item to the retry chain for updating the retry database
3931 at the end of delivery. We only need to add the item to the top address,
3932 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
3933 for any other delivery attempts using the same address. (It is copied into
3934 the unusable tree at the outer level, so even if different address blocks
3935 contain the same address, it still won't get tried again.) */
3937 if (rc == DEFER || retry_host_key)
3939 int delete_flag = rc != DEFER ? rf_delete : 0;
3940 if (!retry_host_key)
3943 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3944 US"retry_include_ip_address", ob->retry_include_ip_address,
3945 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3946 incl_ip = TRUE; /* error; use most-specific retry record */
3948 retry_host_key = incl_ip
3949 ? string_sprintf("T:%S:%s%s", host->name, host->address, pistring)
3950 : string_sprintf("T:%S%s", host->name, pistring);
3953 /* If a delivery of another message over an existing SMTP connection
3954 yields DEFER, we do NOT set up retry data for the host. This covers the
3955 case when there are delays in routing the addresses in the second message
3956 that are so long that the server times out. This is alleviated by not
3957 routing addresses that previously had routing defers when handling an
3958 existing connection, but even so, this case may occur (e.g. if a
3959 previously happily routed address starts giving routing defers). If the
3960 host is genuinely down, another non-continued message delivery will
3961 notice it soon enough. */
3963 if (delete_flag != 0 || !continue_hostname)
3964 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
3966 /* We may have tried an expired host, if its retry time has come; ensure
3967 the status reflects the expiry for the benefit of any other addresses. */
3971 host->status = host_is_expired
3972 ? hstatus_unusable_expired : hstatus_unusable;
3973 host->why = hwhy_deferred;
3977 /* If message_defer is set (host was OK, but every recipient got deferred
3978 because of some message-specific problem), or if that had happened
3979 previously so that a message retry key exists, add an appropriate item
3980 to the retry chain. Note that if there was a message defer but now there is
3981 a host defer, the message defer record gets deleted. That seems perfectly
3982 reasonable. Also, stop the message from being remembered as waiting
3983 for specific hosts. */
3985 if (message_defer || retry_message_key)
3987 int delete_flag = message_defer ? 0 : rf_delete;
3988 if (!retry_message_key)
3991 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3992 US"retry_include_ip_address", ob->retry_include_ip_address,
3993 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3994 incl_ip = TRUE; /* error; use most-specific retry record */
3996 retry_message_key = incl_ip
3997 ? string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
3999 : string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
4001 retry_add_item(addrlist, retry_message_key,
4002 rf_message | rf_host | delete_flag);
4003 update_waiting = FALSE;
4006 /* Any return other than DEFER (that is, OK or ERROR) means that the
4007 addresses have got their final statuses filled in for this host. In the OK
4008 case, see if any of them are deferred. */
4011 for (addr = addrlist; addr; addr = addr->next)
4012 if (addr->transport_return == DEFER)
4014 some_deferred = TRUE;
4018 /* If no addresses deferred or the result was ERROR, return. We do this for
4019 ERROR because a failing filter set-up or add_headers expansion is likely to
4020 fail for any host we try. */
4022 if (rc == ERROR || (rc == OK && !some_deferred))
4024 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
4025 return TRUE; /* Each address has its status */
4028 /* If the result was DEFER or some individual addresses deferred, let
4029 the loop run to try other hosts with the deferred addresses, except for the
4030 case when we were trying to deliver down an existing channel and failed.
4031 Don't try any other hosts in this case. */
4033 if (continue_hostname) break;
4035 /* If the whole delivery, or some individual addresses, were deferred and
4036 there are more hosts that could be tried, do not count this host towards
4037 the hosts_max_try limit if the age of the message is greater than the
4038 maximum retry time for this host. This means we may try try all hosts,
4039 ignoring the limit, when messages have been around for some time. This is
4040 important because if we don't try all hosts, the address will never time
4041 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
4043 if ((rc == DEFER || some_deferred) && nexthost)
4046 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
4048 if (retry && retry->rules)
4050 retry_rule *last_rule;
4051 for (last_rule = retry->rules;
4053 last_rule = last_rule->next);
4054 timedout = time(NULL) - received_time > last_rule->timeout;
4056 else timedout = TRUE; /* No rule => timed out */
4060 unexpired_hosts_tried--;
4061 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
4062 "hosts_max_try (message older than host's retry time)\n");
4065 } /* End of loop for trying multiple hosts. */
4067 /* This is the end of the loop that repeats iff expired is TRUE and
4068 ob->delay_after_cutoff is FALSE. The second time round we will
4069 try those hosts that haven't been tried since the message arrived. */
4073 debug_printf("all IP addresses skipped or deferred at least one address\n");
4074 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
4075 debug_printf("retrying IP addresses not tried since message arrived\n");
4080 /* Get here if all IP addresses are skipped or defer at least one address. In
4081 MUA wrapper mode, this will happen only for connection or other non-message-
4082 specific failures. Force the delivery status for all addresses to FAIL. */
4086 for (addr = addrlist; addr; addr = addr->next)
4087 addr->transport_return = FAIL;
4091 /* In the normal, non-wrapper case, add a standard message to each deferred
4092 address if there hasn't been an error, that is, if it hasn't actually been
4093 tried this time. The variable "expired" will be FALSE if any deliveries were
4094 actually tried, or if there was at least one host that was not expired. That
4095 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
4096 a delivery has been tried, an error code will be set, and the failing of the
4097 message is handled by the retry code later.
4099 If queue_smtp is set, or this transport was called to send a subsequent message
4100 down an existing TCP/IP connection, and something caused the host not to be
4101 found, we end up here, but can detect these cases and handle them specially. */
4103 for (addr = addrlist; addr; addr = addr->next)
4105 /* If host is not NULL, it means that we stopped processing the host list
4106 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
4107 means we need to behave as if some hosts were skipped because their retry
4108 time had not come. Specifically, this prevents the address from timing out.
4109 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
4110 hosts were tried. */
4113 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
4116 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
4117 "hosts were tried\n");
4122 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
4123 setflag(addr, af_retry_skipped);
4126 if (queue_smtp) /* no deliveries attempted */
4128 addr->transport_return = DEFER;
4129 addr->basic_errno = 0;
4130 addr->message = US"SMTP delivery explicitly queued";
4133 else if ( addr->transport_return == DEFER
4134 && (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0)
4138 addr->basic_errno = ERRNO_HRETRY;
4139 if (continue_hostname)
4140 addr->message = US"no host found for existing SMTP connection";
4143 setflag(addr, af_pass_message); /* This is not a security risk */
4144 addr->message = string_sprintf(
4145 "all hosts%s have been failing for a long time %s",
4146 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"",
4147 ob->delay_after_cutoff
4148 ? US"(and retry time not reached)"
4149 : US"and were last tried after this message arrived");
4151 /* If we are already using fallback hosts, or there are no fallback hosts
4152 defined, convert the result to FAIL to cause a bounce. */
4154 if (addr->host_list == addr->fallback_hosts || !addr->fallback_hosts)
4155 addr->transport_return = FAIL;
4160 if (hosts_retry == hosts_total)
4161 s = "retry time not reached for any host%s";
4162 else if (hosts_fail == hosts_total)
4163 s = "all host address lookups%s failed permanently";
4164 else if (hosts_defer == hosts_total)
4165 s = "all host address lookups%s failed temporarily";
4166 else if (hosts_serial == hosts_total)
4167 s = "connection limit reached for all hosts%s";
4168 else if (hosts_fail+hosts_defer == hosts_total)
4169 s = "all host address lookups%s failed";
4171 s = "some host address lookups failed and retry time "
4172 "not reached for other hosts or connection limit reached%s";
4174 addr->message = string_sprintf(s,
4175 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"");
4180 /* Update the database which keeps information about which messages are waiting
4181 for which hosts to become available. For some message-specific errors, the
4182 update_waiting flag is turned off because we don't want follow-on deliveries in
4183 those cases. If this transport instance is explicitly limited to one message
4184 per connection then follow-on deliveries are not possible and there's no need
4185 to create/update the per-transport wait-<transport_name> database. */
4187 if (update_waiting && tblock->connection_max_messages != 1)
4188 transport_update_waiting(hostlist, tblock->name);
4192 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
4194 return TRUE; /* Each address has its status */
4199 /* End of transport/smtp.c */