1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2014 */
6 /* See the file NOTICE for conditions of use and distribution. */
12 #define PENDING_DEFER (PENDING + DEFER)
13 #define PENDING_OK (PENDING + OK)
16 /* Options specific to the smtp transport. This transport also supports LMTP
17 over TCP/IP. The options must be in alphabetic order (note that "_" comes
18 before the lower case letters). Some live in the transport_instance block so as
19 to be publicly visible; these are flagged with opt_public. */
21 optionlist smtp_transport_options[] = {
22 { "address_retry_include_sender", opt_bool,
23 (void *)offsetof(smtp_transport_options_block, address_retry_include_sender) },
24 { "allow_localhost", opt_bool,
25 (void *)offsetof(smtp_transport_options_block, allow_localhost) },
26 { "authenticated_sender", opt_stringptr,
27 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
28 { "authenticated_sender_force", opt_bool,
29 (void *)offsetof(smtp_transport_options_block, authenticated_sender_force) },
30 { "command_timeout", opt_time,
31 (void *)offsetof(smtp_transport_options_block, command_timeout) },
32 { "connect_timeout", opt_time,
33 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
34 { "connection_max_messages", opt_int | opt_public,
35 (void *)offsetof(transport_instance, connection_max_messages) },
36 { "data_timeout", opt_time,
37 (void *)offsetof(smtp_transport_options_block, data_timeout) },
38 { "delay_after_cutoff", opt_bool,
39 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
41 { "dkim_canon", opt_stringptr,
42 (void *)offsetof(smtp_transport_options_block, dkim_canon) },
43 { "dkim_domain", opt_stringptr,
44 (void *)offsetof(smtp_transport_options_block, dkim_domain) },
45 { "dkim_private_key", opt_stringptr,
46 (void *)offsetof(smtp_transport_options_block, dkim_private_key) },
47 { "dkim_selector", opt_stringptr,
48 (void *)offsetof(smtp_transport_options_block, dkim_selector) },
49 { "dkim_sign_headers", opt_stringptr,
50 (void *)offsetof(smtp_transport_options_block, dkim_sign_headers) },
51 { "dkim_strict", opt_stringptr,
52 (void *)offsetof(smtp_transport_options_block, dkim_strict) },
54 { "dns_qualify_single", opt_bool,
55 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
56 { "dns_search_parents", opt_bool,
57 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
58 { "dnssec_request_domains", opt_stringptr,
59 (void *)offsetof(smtp_transport_options_block, dnssec_request_domains) },
60 { "dnssec_require_domains", opt_stringptr,
61 (void *)offsetof(smtp_transport_options_block, dnssec_require_domains) },
62 { "dscp", opt_stringptr,
63 (void *)offsetof(smtp_transport_options_block, dscp) },
64 { "fallback_hosts", opt_stringptr,
65 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
66 { "final_timeout", opt_time,
67 (void *)offsetof(smtp_transport_options_block, final_timeout) },
68 { "gethostbyname", opt_bool,
69 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
71 /* These are no longer honoured, as of Exim 4.80; for now, we silently
72 ignore; 4.83 will warn, and a later-still release will remove
73 these options, so that using them becomes an error. */
74 { "gnutls_require_kx", opt_stringptr,
75 (void *)offsetof(smtp_transport_options_block, gnutls_require_kx) },
76 { "gnutls_require_mac", opt_stringptr,
77 (void *)offsetof(smtp_transport_options_block, gnutls_require_mac) },
78 { "gnutls_require_protocols", opt_stringptr,
79 (void *)offsetof(smtp_transport_options_block, gnutls_require_proto) },
81 { "helo_data", opt_stringptr,
82 (void *)offsetof(smtp_transport_options_block, helo_data) },
83 { "hosts", opt_stringptr,
84 (void *)offsetof(smtp_transport_options_block, hosts) },
85 { "hosts_avoid_esmtp", opt_stringptr,
86 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
87 { "hosts_avoid_pipelining", opt_stringptr,
88 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
90 { "hosts_avoid_tls", opt_stringptr,
91 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
93 { "hosts_max_try", opt_int,
94 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
95 { "hosts_max_try_hardlimit", opt_int,
96 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
98 { "hosts_nopass_tls", opt_stringptr,
99 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
101 { "hosts_override", opt_bool,
102 (void *)offsetof(smtp_transport_options_block, hosts_override) },
103 { "hosts_randomize", opt_bool,
104 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
105 #if defined(SUPPORT_TLS) && !defined(DISABLE_OCSP)
106 { "hosts_request_ocsp", opt_stringptr,
107 (void *)offsetof(smtp_transport_options_block, hosts_request_ocsp) },
109 { "hosts_require_auth", opt_stringptr,
110 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
112 # 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) },
122 { "hosts_try_prdr", opt_stringptr,
123 (void *)offsetof(smtp_transport_options_block, hosts_try_prdr) },
126 { "hosts_verify_avoid_tls", opt_stringptr,
127 (void *)offsetof(smtp_transport_options_block, hosts_verify_avoid_tls) },
129 { "interface", opt_stringptr,
130 (void *)offsetof(smtp_transport_options_block, interface) },
131 { "keepalive", opt_bool,
132 (void *)offsetof(smtp_transport_options_block, keepalive) },
133 { "lmtp_ignore_quota", opt_bool,
134 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
135 { "max_rcpt", opt_int | opt_public,
136 (void *)offsetof(transport_instance, max_addresses) },
137 { "multi_domain", opt_bool | opt_public,
138 (void *)offsetof(transport_instance, multi_domain) },
139 { "port", opt_stringptr,
140 (void *)offsetof(smtp_transport_options_block, port) },
141 { "protocol", opt_stringptr,
142 (void *)offsetof(smtp_transport_options_block, protocol) },
143 { "retry_include_ip_address", opt_bool,
144 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
145 { "serialize_hosts", opt_stringptr,
146 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
147 { "size_addition", opt_int,
148 (void *)offsetof(smtp_transport_options_block, size_addition) }
150 ,{ "tls_certificate", opt_stringptr,
151 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
152 { "tls_crl", opt_stringptr,
153 (void *)offsetof(smtp_transport_options_block, tls_crl) },
154 { "tls_dh_min_bits", opt_int,
155 (void *)offsetof(smtp_transport_options_block, tls_dh_min_bits) },
156 { "tls_privatekey", opt_stringptr,
157 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
158 { "tls_require_ciphers", opt_stringptr,
159 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
160 { "tls_sni", opt_stringptr,
161 (void *)offsetof(smtp_transport_options_block, tls_sni) },
162 { "tls_tempfail_tryclear", opt_bool,
163 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
164 { "tls_try_verify_hosts", opt_stringptr,
165 (void *)offsetof(smtp_transport_options_block, tls_try_verify_hosts) },
166 #ifdef EXPERIMENTAL_CERTNAMES
167 { "tls_verify_cert_hostnames", opt_stringptr,
168 (void *)offsetof(smtp_transport_options_block,tls_verify_cert_hostnames)},
170 { "tls_verify_certificates", opt_stringptr,
171 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) },
172 { "tls_verify_hosts", opt_stringptr,
173 (void *)offsetof(smtp_transport_options_block, tls_verify_hosts) }
175 #ifdef EXPERIMENTAL_TPDA
176 ,{ "tpda_host_defer_action", opt_stringptr,
177 (void *)offsetof(smtp_transport_options_block, tpda_host_defer_action) },
181 /* Size of the options list. An extern variable has to be used so that its
182 address can appear in the tables drtables.c. */
184 int smtp_transport_options_count =
185 sizeof(smtp_transport_options)/sizeof(optionlist);
187 /* Default private options block for the smtp transport. */
189 smtp_transport_options_block smtp_transport_option_defaults = {
191 NULL, /* fallback_hosts */
193 NULL, /* fallback_hostlist */
194 NULL, /* authenticated_sender */
195 US"$primary_hostname", /* helo_data */
196 NULL, /* interface */
198 US"smtp", /* protocol */
200 NULL, /* serialize_hosts */
201 NULL, /* hosts_try_auth */
202 NULL, /* hosts_require_auth */
204 NULL, /* hosts_try_prdr */
207 US"*", /* hosts_request_ocsp */
208 NULL, /* hosts_require_ocsp */
210 NULL, /* hosts_require_tls */
211 NULL, /* hosts_avoid_tls */
212 US"*", /* hosts_verify_avoid_tls */
213 NULL, /* hosts_avoid_pipelining */
214 NULL, /* hosts_avoid_esmtp */
215 NULL, /* hosts_nopass_tls */
216 5*60, /* command_timeout */
217 5*60, /* connect_timeout; shorter system default overrides */
218 5*60, /* data timeout */
219 10*60, /* final timeout */
220 1024, /* size_addition */
221 5, /* hosts_max_try */
222 50, /* hosts_max_try_hardlimit */
223 TRUE, /* address_retry_include_sender */
224 FALSE, /* allow_localhost */
225 FALSE, /* authenticated_sender_force */
226 FALSE, /* gethostbyname */
227 TRUE, /* dns_qualify_single */
228 FALSE, /* dns_search_parents */
229 NULL, /* dnssec_request_domains */
230 NULL, /* dnssec_require_domains */
231 TRUE, /* delay_after_cutoff */
232 FALSE, /* hosts_override */
233 FALSE, /* hosts_randomize */
234 TRUE, /* keepalive */
235 FALSE, /* lmtp_ignore_quota */
236 TRUE /* retry_include_ip_address */
238 ,NULL, /* tls_certificate */
240 NULL, /* tls_privatekey */
241 NULL, /* tls_require_ciphers */
242 NULL, /* gnutls_require_kx */
243 NULL, /* gnutls_require_mac */
244 NULL, /* gnutls_require_proto */
246 NULL, /* tls_verify_certificates */
247 EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
248 /* tls_dh_min_bits */
249 TRUE, /* tls_tempfail_tryclear */
250 NULL, /* tls_verify_hosts */
251 NULL /* tls_try_verify_hosts */
252 # ifdef EXPERIMENTAL_CERTNAMES
253 ,NULL /* tls_verify_cert_hostnames */
257 ,NULL, /* dkim_canon */
258 NULL, /* dkim_domain */
259 NULL, /* dkim_private_key */
260 NULL, /* dkim_selector */
261 NULL, /* dkim_sign_headers */
262 NULL /* dkim_strict */
264 #ifdef EXPERIMENTAL_TPDA
265 ,NULL /* tpda_host_defer_action */
269 #ifdef EXPERIMENTAL_DSN
270 /* some DSN flags for use later */
272 static int rf_list[] = {rf_notify_never, rf_notify_success,
273 rf_notify_failure, rf_notify_delay };
275 static uschar *rf_names[] = { "NEVER", "SUCCESS", "FAILURE", "DELAY" };
282 static uschar *smtp_command; /* Points to last cmd for error messages */
283 static uschar *mail_command; /* Points to MAIL cmd for error messages */
284 static BOOL update_waiting; /* TRUE to update the "wait" database */
287 /*************************************************
288 * Setup entry point *
289 *************************************************/
291 /* This function is called when the transport is about to be used,
292 but before running it in a sub-process. It is used for two things:
294 (1) To set the fallback host list in addresses, when delivering.
295 (2) To pass back the interface, port, protocol, and other options, for use
296 during callout verification.
299 tblock pointer to the transport instance block
300 addrlist list of addresses about to be transported
301 tf if not NULL, pointer to block in which to return options
302 uid the uid that will be set (not used)
303 gid the gid that will be set (not used)
304 errmsg place for error message (not used)
306 Returns: OK always (FAIL, DEFER not used)
310 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
311 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
313 smtp_transport_options_block *ob =
314 (smtp_transport_options_block *)(tblock->options_block);
316 errmsg = errmsg; /* Keep picky compilers happy */
320 /* Pass back options if required. This interface is getting very messy. */
324 tf->interface = ob->interface;
326 tf->protocol = ob->protocol;
327 tf->hosts = ob->hosts;
328 tf->hosts_override = ob->hosts_override;
329 tf->hosts_randomize = ob->hosts_randomize;
330 tf->gethostbyname = ob->gethostbyname;
331 tf->qualify_single = ob->dns_qualify_single;
332 tf->search_parents = ob->dns_search_parents;
333 tf->helo_data = ob->helo_data;
336 /* Set the fallback host list for all the addresses that don't have fallback
337 host lists, provided that the local host wasn't present in the original host
340 if (!testflag(addrlist, af_local_host_removed))
342 for (; addrlist != NULL; addrlist = addrlist->next)
343 if (addrlist->fallback_hosts == NULL)
344 addrlist->fallback_hosts = ob->fallback_hostlist;
352 /*************************************************
353 * Initialization entry point *
354 *************************************************/
356 /* Called for each instance, after its options have been read, to
357 enable consistency checks to be done, or anything else that needs
360 Argument: pointer to the transport instance block
365 smtp_transport_init(transport_instance *tblock)
367 smtp_transport_options_block *ob =
368 (smtp_transport_options_block *)(tblock->options_block);
370 /* Retry_use_local_part defaults FALSE if unset */
372 if (tblock->retry_use_local_part == TRUE_UNSET)
373 tblock->retry_use_local_part = FALSE;
375 /* Set the default port according to the protocol */
377 if (ob->port == NULL)
378 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
379 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
381 /* Set up the setup entry point, to be called before subprocesses for this
384 tblock->setup = smtp_transport_setup;
386 /* Complain if any of the timeouts are zero. */
388 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
389 ob->final_timeout <= 0)
390 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
391 "command, data, or final timeout value is zero for %s transport",
394 /* If hosts_override is set and there are local hosts, set the global
395 flag that stops verify from showing router hosts. */
397 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
399 /* If there are any fallback hosts listed, build a chain of host items
400 for them, but do not do any lookups at this time. */
402 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
405 if ( ob->gnutls_require_kx
406 || ob->gnutls_require_mac
407 || ob->gnutls_require_proto)
408 log_write(0, LOG_MAIN, "WARNING: smtp transport options"
409 " gnutls_require_kx, gnutls_require_mac and gnutls_require_protocols"
418 /*************************************************
419 * Set delivery info into all active addresses *
420 *************************************************/
422 /* Only addresses whose status is >= PENDING are relevant. A lesser
423 status means that an address is not currently being processed.
426 addrlist points to a chain of addresses
427 errno_value to put in each address's errno field
428 msg to put in each address's message field
429 rc to put in each address's transport_return field
430 pass_message if TRUE, set the "pass message" flag in the address
432 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
433 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
434 this particular type of timeout.
440 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
445 if (errno_value == ERRNO_CONNECTTIMEOUT)
447 errno_value = ETIMEDOUT;
448 orvalue = RTEF_CTOUT;
450 for (addr = addrlist; addr != NULL; addr = addr->next)
452 if (addr->transport_return < PENDING) continue;
453 addr->basic_errno = errno_value;
454 addr->more_errno |= orvalue;
458 if (pass_message) setflag(addr, af_pass_message);
460 addr->transport_return = rc;
466 /*************************************************
467 * Check an SMTP response *
468 *************************************************/
470 /* This function is given an errno code and the SMTP response buffer
471 to analyse, together with the host identification for generating messages. It
472 sets an appropriate message and puts the first digit of the response code into
473 the yield variable. If no response was actually read, a suitable digit is
477 host the current host, to get its name for messages
478 errno_value pointer to the errno value
479 more_errno from the top address for use with ERRNO_FILTER_FAIL
480 buffer the SMTP response buffer
481 yield where to put a one-digit SMTP response code
482 message where to put an errror message
483 pass_message set TRUE if message is an SMTP response
485 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
488 static BOOL check_response(host_item *host, int *errno_value, int more_errno,
489 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
493 if (smtp_use_pipelining &&
494 (Ustrcmp(smtp_command, "MAIL") == 0 ||
495 Ustrcmp(smtp_command, "RCPT") == 0 ||
496 Ustrcmp(smtp_command, "DATA") == 0))
499 *yield = '4'; /* Default setting is to give a temporary error */
501 /* Handle response timeout */
503 if (*errno_value == ETIMEDOUT)
505 *message = US string_sprintf("SMTP timeout while connected to %s [%s] "
506 "after %s%s", host->name, host->address, pl, smtp_command);
507 if (transport_count > 0)
508 *message = US string_sprintf("%s (%d bytes written)", *message,
513 /* Handle malformed SMTP response */
515 if (*errno_value == ERRNO_SMTPFORMAT)
517 uschar *malfresp = string_printing(buffer);
518 while (isspace(*malfresp)) malfresp++;
520 *message = string_sprintf("Malformed SMTP reply (an empty line) from "
521 "%s [%s] in response to %s%s", host->name, host->address, pl,
524 *message = string_sprintf("Malformed SMTP reply from %s [%s] in response "
525 "to %s%s: %s", host->name, host->address, pl, smtp_command, malfresp);
529 /* Handle a failed filter process error; can't send QUIT as we mustn't
532 if (*errno_value == ERRNO_FILTER_FAIL)
534 *message = US string_sprintf("transport filter process failed (%d)%s",
536 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
540 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
543 if (*errno_value == ERRNO_CHHEADER_FAIL)
546 US string_sprintf("failed to expand headers_add or headers_remove: %s",
547 expand_string_message);
551 /* Handle failure to write a complete data block */
553 if (*errno_value == ERRNO_WRITEINCOMPLETE)
555 *message = US string_sprintf("failed to write a data block");
559 /* Handle error responses from the remote mailer. */
563 uschar *s = string_printing(buffer);
564 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
565 "host %s [%s]: %s", pl, smtp_command, host->name, host->address, s);
566 *pass_message = TRUE;
571 /* No data was read. If there is no errno, this must be the EOF (i.e.
572 connection closed) case, which causes deferral. An explicit connection reset
573 error has the same effect. Otherwise, put the host's identity in the message,
574 leaving the errno value to be interpreted as well. In all cases, we have to
575 assume the connection is now dead. */
577 if (*errno_value == 0 || *errno_value == ECONNRESET)
579 *errno_value = ERRNO_SMTPCLOSED;
580 *message = US string_sprintf("Remote host %s [%s] closed connection "
581 "in response to %s%s", host->name, host->address, pl, smtp_command);
583 else *message = US string_sprintf("%s [%s]", host->name, host->address);
590 /*************************************************
591 * Write error message to logs *
592 *************************************************/
594 /* This writes to the main log and to the message log.
597 addr the address item containing error information
598 host the current host
604 write_logs(address_item *addr, host_item *host)
606 if (addr->message != NULL)
608 uschar *message = addr->message;
609 if (addr->basic_errno > 0)
610 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
611 log_write(0, LOG_MAIN, "%s", message);
612 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
617 ((log_extra_selector & LX_outgoing_port) != 0)?
618 string_sprintf("%s [%s]:%d", host->name, host->address,
619 (host->port == PORT_NONE)? 25 : host->port)
621 string_sprintf("%s [%s]", host->name, host->address);
622 log_write(0, LOG_MAIN, "%s %s", msg, strerror(addr->basic_errno));
623 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), msg,
624 strerror(addr->basic_errno));
630 #ifdef EXPERIMENTAL_TPDA
631 /*************************************************
632 * Post-defer action *
633 *************************************************/
635 /* This expands an arbitrary per-transport string.
636 It might, for example, be used to write to the database log.
639 ob transport options block
640 addr the address item containing error information
641 host the current host
647 tpda_deferred(smtp_transport_options_block *ob, address_item *addr, host_item *host)
649 uschar *action = ob->tpda_host_defer_action;
653 tpda_delivery_ip = string_copy(host->address);
654 tpda_delivery_port = (host->port == PORT_NONE)? 25 : host->port;
655 tpda_delivery_fqdn = string_copy(host->name);
656 tpda_delivery_local_part = string_copy(addr->local_part);
657 tpda_delivery_domain = string_copy(addr->domain);
658 tpda_defer_errno = addr->basic_errno;
660 tpda_defer_errstr = addr->message
661 ? addr->basic_errno > 0
662 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
663 : string_copy(addr->message)
664 : addr->basic_errno > 0
665 ? string_copy(US strerror(addr->basic_errno))
669 debug_printf(" TPDA(host defer): tpda_host_defer_action=|%s| tpda_delivery_IP=%s\n",
670 action, tpda_delivery_ip);
672 router_name = addr->router->name;
673 transport_name = addr->transport->name;
674 if (!expand_string(action) && *expand_string_message)
675 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand tpda_defer_action in %s: %s\n",
676 transport_name, expand_string_message);
677 router_name = transport_name = NULL;
683 /*************************************************
684 * Synchronize SMTP responses *
685 *************************************************/
687 /* This function is called from smtp_deliver() to receive SMTP responses from
688 the server, and match them up with the commands to which they relate. When
689 PIPELINING is not in use, this function is called after every command, and is
690 therefore somewhat over-engineered, but it is simpler to use a single scheme
691 that works both with and without PIPELINING instead of having two separate sets
694 The set of commands that are buffered up with pipelining may start with MAIL
695 and may end with DATA; in between are RCPT commands that correspond to the
696 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
697 etc.) are never buffered.
699 Errors after MAIL or DATA abort the whole process leaving the response in the
700 buffer. After MAIL, pending responses are flushed, and the original command is
701 re-instated in big_buffer for error messages. For RCPT commands, the remote is
702 permitted to reject some recipient addresses while accepting others. However
703 certain errors clearly abort the whole process. Set the value in
704 transport_return to PENDING_OK if the address is accepted. If there is a
705 subsequent general error, it will get reset accordingly. If not, it will get
706 converted to OK at the end.
709 addrlist the complete address list
710 include_affixes TRUE if affixes include in RCPT
711 sync_addr ptr to the ptr of the one to start scanning at (updated)
712 host the host we are connected to
713 count the number of responses to read
715 include_sender true if 4xx retry is to include the sender it its key
716 pending_MAIL true if the first response is for MAIL
717 pending_DATA 0 if last command sent was not DATA
718 +1 if previously had a good recipient
719 -1 if not previously had a good recipient
720 inblock incoming SMTP block
721 timeout timeout value
722 buffer buffer for reading response
723 buffsize size of buffer
725 Returns: 3 if at least one address had 2xx and one had 5xx
726 2 if at least one address had 5xx but none had 2xx
727 1 if at least one host had a 2xx response, but none had 5xx
728 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
729 -1 timeout while reading RCPT response
730 -2 I/O or other non-response error for RCPT
731 -3 DATA or MAIL failed - errno and buffer set
735 sync_responses(address_item *addrlist, BOOL include_affixes,
736 address_item **sync_addr, host_item *host, int count,
737 BOOL address_retry_include_sender, BOOL pending_MAIL,
738 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
741 address_item *addr = *sync_addr;
744 /* Handle the response for a MAIL command. On error, reinstate the original
745 command in big_buffer for error message use, and flush any further pending
746 responses before returning, except after I/O errors and timeouts. */
751 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
753 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
754 if (errno == 0 && buffer[0] != 0)
756 uschar flushbuffer[4096];
758 if (buffer[0] == '4')
760 save_errno = ERRNO_MAIL4XX;
761 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
765 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
767 && (errno != 0 || flushbuffer[0] == 0))
776 if (pending_DATA) count--; /* Number of RCPT responses to come */
778 /* Read and handle the required number of RCPT responses, matching each one up
779 with an address by scanning for the next address whose status is PENDING_DEFER.
784 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
786 /* The address was accepted */
788 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
791 addr->transport_return = PENDING_OK;
793 /* If af_dr_retry_exists is set, there was a routing delay on this address;
794 ensure that any address-specific retry record is expunged. We do this both
795 for the basic key and for the version that also includes the sender. */
797 if (testflag(addr, af_dr_retry_exists))
799 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
801 retry_add_item(addr, altkey, rf_delete);
802 retry_add_item(addr, addr->address_retry_key, rf_delete);
806 /* Timeout while reading the response */
808 else if (errno == ETIMEDOUT)
810 int save_errno = errno;
811 uschar *message = string_sprintf("SMTP timeout while connected to %s [%s] "
812 "after RCPT TO:<%s>", host->name, host->address,
813 transport_rcpt_address(addr, include_affixes));
814 set_errno(addrlist, save_errno, message, DEFER, FALSE);
815 retry_add_item(addr, addr->address_retry_key, 0);
816 update_waiting = FALSE;
820 /* Handle other errors in obtaining an SMTP response by returning -1. This
821 will cause all the addresses to be deferred. Restore the SMTP command in
822 big_buffer for which we are checking the response, so the error message
825 else if (errno != 0 || buffer[0] == 0)
827 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
828 transport_rcpt_address(addr, include_affixes));
832 /* Handle SMTP permanent and temporary response codes. */
837 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
838 "host %s [%s]: %s", transport_rcpt_address(addr, include_affixes),
839 host->name, host->address, string_printing(buffer));
840 setflag(addr, af_pass_message);
841 deliver_msglog("%s %s\n", tod_stamp(tod_log), addr->message);
843 /* The response was 5xx */
845 if (buffer[0] == '5')
847 addr->transport_return = FAIL;
851 /* The response was 4xx */
855 addr->transport_return = DEFER;
856 addr->basic_errno = ERRNO_RCPT4XX;
857 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
859 /* Log temporary errors if there are more hosts to be tried. */
861 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", addr->message);
863 /* Do not put this message on the list of those waiting for specific
864 hosts, as otherwise it is likely to be tried too often. */
866 update_waiting = FALSE;
868 /* Add a retry item for the address so that it doesn't get tried again
869 too soon. If address_retry_include_sender is true, add the sender address
872 if (address_retry_include_sender)
874 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
876 retry_add_item(addr, altkey, 0);
878 else retry_add_item(addr, addr->address_retry_key, 0);
881 } /* Loop for next RCPT response */
883 /* Update where to start at for the next block of responses, unless we
884 have already handled all the addresses. */
886 if (addr != NULL) *sync_addr = addr->next;
888 /* Handle a response to DATA. If we have not had any good recipients, either
889 previously or in this block, the response is ignored. */
891 if (pending_DATA != 0 &&
892 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
897 if (pending_DATA > 0 || (yield & 1) != 0)
899 if (errno == 0 && buffer[0] == '4')
901 errno = ERRNO_DATA4XX;
902 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
906 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
907 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
908 "is in use and there were no good recipients\n", msg);
911 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
912 present) received 3xx. If any RCPTs were handled and yielded anything other
913 than 4xx, yield will be set non-zero. */
920 /* Do the client side of smtp-level authentication */
923 buffer EHLO response from server (gets overwritten)
924 addrlist chain of potential addresses to deliver
925 host host to deliver to
927 ibp, obp comms channel control blocks
930 OK Success, or failed (but not required): global "smtp_authenticated" set
931 DEFER Failed authentication (and was required)
932 ERROR Internal problem
934 FAIL_SEND Failed communications - transmit
939 smtp_auth(uschar *buffer, unsigned bufsize, address_item *addrlist, host_item *host,
940 smtp_transport_options_block *ob, BOOL is_esmtp,
941 smtp_inblock *ibp, smtp_outblock *obp)
944 uschar *fail_reason = US"server did not advertise AUTH support";
946 smtp_authenticated = FALSE;
947 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
948 require_auth = verify_check_this_host(&(ob->hosts_require_auth), NULL,
949 host->name, host->address, NULL);
951 if (is_esmtp && !regex_AUTH) regex_AUTH =
952 regex_must_compile(US"\\n250[\\s\\-]AUTH\\s+([\\-\\w\\s]+)(?:\\n|$)",
955 if (is_esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
957 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
958 expand_nmax = -1; /* reset */
960 /* Must not do this check until after we have saved the result of the
961 regex match above. */
963 if (require_auth == OK ||
964 verify_check_this_host(&(ob->hosts_try_auth), NULL, host->name,
965 host->address, NULL) == OK)
968 fail_reason = US"no common mechanisms were found";
970 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
972 /* Scan the configured authenticators looking for one which is configured
973 for use as a client, which is not suppressed by client_condition, and
974 whose name matches an authentication mechanism supported by the server.
975 If one is found, attempt to authenticate by calling its client function.
978 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
982 (au->client_condition != NULL &&
983 !expand_check_condition(au->client_condition, au->name,
984 US"client authenticator")))
986 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
988 (au->client)? "client_condition is false" :
989 "not configured as a client");
993 /* Loop to scan supported server mechanisms */
998 int len = Ustrlen(au->public_name);
999 while (isspace(*p)) p++;
1001 if (strncmpic(au->public_name, p, len) != 0 ||
1002 (p[len] != 0 && !isspace(p[len])))
1004 while (*p != 0 && !isspace(*p)) p++;
1008 /* Found data for a listed mechanism. Call its client entry. Set
1009 a flag in the outblock so that data is overwritten after sending so
1010 that reflections don't show it. */
1012 fail_reason = US"authentication attempt(s) failed";
1013 obp->authenticating = TRUE;
1014 rc = (au->info->clientcode)(au, ibp, obp,
1015 ob->command_timeout, buffer, bufsize);
1016 obp->authenticating = FALSE;
1017 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1020 /* A temporary authentication failure must hold up delivery to
1021 this host. After a permanent authentication failure, we carry on
1022 to try other authentication methods. If all fail hard, try to
1023 deliver the message unauthenticated unless require_auth was set. */
1028 smtp_authenticated = TRUE; /* stops the outer loop */
1029 client_authenticator = au->name;
1030 if (au->set_client_id != NULL)
1031 client_authenticated_id = expand_string(au->set_client_id);
1034 /* Failure after writing a command */
1039 /* Failure after reading a response */
1042 if (errno != 0 || buffer[0] != '5') return FAIL;
1043 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1044 au->name, host->name, host->address, buffer);
1047 /* Failure by some other means. In effect, the authenticator
1048 decided it wasn't prepared to handle this case. Typically this
1049 is the result of "fail" in an expansion string. Do we need to
1050 log anything here? Feb 2006: a message is now put in the buffer
1051 if logging is required. */
1055 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1056 "authentication H=%s [%s] %s", au->name, host->name,
1057 host->address, buffer);
1060 /* Internal problem, message in buffer. */
1063 set_errno(addrlist, 0, string_copy(buffer), DEFER, FALSE);
1067 break; /* If not authenticated, try next authenticator */
1068 } /* Loop for scanning supported server mechanisms */
1069 } /* Loop for further authenticators */
1073 /* If we haven't authenticated, but are required to, give up. */
1075 if (require_auth == OK && !smtp_authenticated)
1077 set_errno(addrlist, ERRNO_AUTHFAIL,
1078 string_sprintf("authentication required but %s", fail_reason), DEFER,
1087 /* Construct AUTH appendix string for MAIL TO */
1090 buffer to build string
1091 addrlist chain of potential addresses to deliver
1092 ob transport options
1094 Globals smtp_authenticated
1095 client_authenticated_sender
1096 Return True on error, otherwise buffer has (possibly empty) terminated string
1100 smtp_mail_auth_str(uschar *buffer, unsigned bufsize, address_item *addrlist,
1101 smtp_transport_options_block *ob)
1103 uschar *local_authenticated_sender = authenticated_sender;
1106 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n", authenticated_sender, ob->authenticated_sender, smtp_authenticated?"Y":"N");
1109 if (ob->authenticated_sender != NULL)
1111 uschar *new = expand_string(ob->authenticated_sender);
1114 if (!expand_string_forcedfail)
1116 uschar *message = string_sprintf("failed to expand "
1117 "authenticated_sender: %s", expand_string_message);
1118 set_errno(addrlist, 0, message, DEFER, FALSE);
1122 else if (new[0] != 0) local_authenticated_sender = new;
1125 /* Add the authenticated sender address if present */
1127 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1128 local_authenticated_sender != NULL)
1130 string_format(buffer, bufsize, " AUTH=%s",
1131 auth_xtextencode(local_authenticated_sender,
1132 Ustrlen(local_authenticated_sender)));
1133 client_authenticated_sender = string_copy(local_authenticated_sender);
1143 /*************************************************
1144 * Deliver address list to given host *
1145 *************************************************/
1147 /* If continue_hostname is not null, we get here only when continuing to
1148 deliver down an existing channel. The channel was passed as the standard
1149 input. TLS is never active on a passed channel; the previous process always
1150 closes it down before passing the connection on.
1152 Otherwise, we have to make a connection to the remote host, and do the
1153 initial protocol exchange.
1155 When running as an MUA wrapper, if the sender or any recipient is rejected,
1156 temporarily or permanently, we force failure for all recipients.
1159 addrlist chain of potential addresses to deliver; only those whose
1160 transport_return field is set to PENDING_DEFER are currently
1161 being processed; others should be skipped - they have either
1162 been delivered to an earlier host or IP address, or been
1163 failed by one of them.
1164 host host to deliver to
1165 host_af AF_INET or AF_INET6
1166 port default TCP/IP port to use, in host byte order
1167 interface interface to bind to, or NULL
1168 tblock transport instance block
1169 copy_host TRUE if host set in addr->host_used must be copied, because
1170 it is specific to this call of the transport
1171 message_defer set TRUE if yield is OK, but all addresses were deferred
1172 because of a non-recipient, non-host failure, that is, a
1173 4xx response to MAIL FROM, DATA, or ".". This is a defer
1174 that is specific to the message.
1175 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1176 a second attempt after TLS initialization fails
1178 Returns: OK - the connection was made and the delivery attempted;
1179 the result for each address is in its data block.
1180 DEFER - the connection could not be made, or something failed
1181 while setting up the SMTP session, or there was a
1182 non-message-specific error, such as a timeout.
1183 ERROR - a filter command is specified for this transport,
1184 and there was a problem setting it up; OR helo_data
1185 or add_headers or authenticated_sender is specified
1186 for this transport, and the string failed to expand
1190 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
1191 uschar *interface, transport_instance *tblock, BOOL copy_host,
1192 BOOL *message_defer, BOOL suppress_tls)
1195 address_item *sync_addr;
1196 address_item *first_addr = addrlist;
1201 time_t start_delivery_time = time(NULL);
1202 smtp_transport_options_block *ob =
1203 (smtp_transport_options_block *)(tblock->options_block);
1204 BOOL lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
1205 BOOL smtps = strcmpic(ob->protocol, US"smtps") == 0;
1207 BOOL send_rset = TRUE;
1208 BOOL send_quit = TRUE;
1209 BOOL setting_up = TRUE;
1210 BOOL completed_address = FALSE;
1213 BOOL pass_message = FALSE;
1214 #ifndef DISABLE_PRDR
1215 BOOL prdr_offered = FALSE;
1218 #ifdef EXPERIMENTAL_DSN
1219 BOOL dsn_all_lasthop = TRUE;
1221 smtp_inblock inblock;
1222 smtp_outblock outblock;
1223 int max_rcpt = tblock->max_addresses;
1224 uschar *igquotstr = US"";
1225 uschar *helo_data = NULL;
1226 uschar *message = NULL;
1227 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
1229 uschar buffer[4096];
1230 uschar inbuffer[4096];
1231 uschar outbuffer[1024];
1233 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
1235 *message_defer = FALSE;
1236 smtp_command = US"initial connection";
1237 if (max_rcpt == 0) max_rcpt = 999999;
1239 /* Set up the buffer for reading SMTP response packets. */
1241 inblock.buffer = inbuffer;
1242 inblock.buffersize = sizeof(inbuffer);
1243 inblock.ptr = inbuffer;
1244 inblock.ptrend = inbuffer;
1246 /* Set up the buffer for holding SMTP commands while pipelining */
1248 outblock.buffer = outbuffer;
1249 outblock.buffersize = sizeof(outbuffer);
1250 outblock.ptr = outbuffer;
1251 outblock.cmd_count = 0;
1252 outblock.authenticating = FALSE;
1254 /* Reset the parameters of a TLS session. */
1257 tls_out.cipher = NULL; /* the one we may use for this transport */
1258 tls_out.ourcert = NULL;
1259 tls_out.peercert = NULL;
1260 tls_out.peerdn = NULL;
1261 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1264 tls_out.ocsp = OCSP_NOT_REQ;
1266 /* Flip the legacy TLS-related variables over to the outbound set in case
1267 they're used in the context of the transport. Don't bother resetting
1268 afterward as we're in a subprocess. */
1270 tls_modify_variables(&tls_out);
1275 set_errno(addrlist, 0, US"TLS support not available", DEFER, FALSE);
1280 /* Make a connection to the host if this isn't a continued delivery, and handle
1281 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
1282 specially so they can be identified for retries. */
1284 if (continue_hostname == NULL)
1286 inblock.sock = outblock.sock =
1287 smtp_connect(host, host_af, port, interface, ob->connect_timeout,
1288 ob->keepalive, ob->dscp); /* This puts port into host->port */
1290 if (inblock.sock < 0)
1292 set_errno(addrlist, (errno == ETIMEDOUT)? ERRNO_CONNECTTIMEOUT : errno,
1293 NULL, DEFER, FALSE);
1297 /* Expand the greeting message while waiting for the initial response. (Makes
1298 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1299 delayed till here so that $sending_interface and $sending_port are set. */
1301 helo_data = expand_string(ob->helo_data);
1303 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1304 is nevertheless a reasonably clean way of programming this kind of logic,
1305 where you want to escape on any error. */
1309 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1310 ob->command_timeout)) goto RESPONSE_FAILED;
1312 /* Now check if the helo_data expansion went well, and sign off cleanly if
1315 if (helo_data == NULL)
1317 uschar *message = string_sprintf("failed to expand helo_data: %s",
1318 expand_string_message);
1319 set_errno(addrlist, 0, message, DEFER, FALSE);
1325 /** Debugging without sending a message
1326 addrlist->transport_return = DEFER;
1330 /* Errors that occur after this point follow an SMTP command, which is
1331 left in big_buffer by smtp_write_command() for use in error messages. */
1333 smtp_command = big_buffer;
1335 /* Tell the remote who we are...
1337 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1338 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1339 greeting is of this form. The assumption was that the far end supports it
1340 properly... but experience shows that there are some that give 5xx responses,
1341 even though the banner includes "ESMTP" (there's a bloody-minded one that
1342 says "ESMTP not spoken here"). Cope with that case.
1344 September 2000: Time has passed, and it seems reasonable now to always send
1345 EHLO at the start. It is also convenient to make the change while installing
1348 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1349 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1350 would be no way to send out the mails, so there is now a host list
1351 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1352 PIPELINING problem as well. Maybe it can also be useful to cure other
1353 problems with broken servers.
1355 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1356 Then somebody tried it with a Microsoft mailer... It seems that all other
1357 mailers use upper case for some reason (the RFC is quite clear about case
1358 independence) so, for peace of mind, I gave in. */
1360 esmtp = verify_check_this_host(&(ob->hosts_avoid_esmtp), NULL,
1361 host->name, host->address, NULL) != OK;
1363 /* Alas; be careful, since this goto is not an error-out, so conceivably
1364 we might set data between here and the target which we assume to exist
1365 and be usable. I can see this coming back to bite us. */
1370 suppress_tls = FALSE;
1371 ob->tls_tempfail_tryclear = FALSE;
1372 smtp_command = US"SSL-on-connect";
1379 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1380 lmtp? "LHLO" : "EHLO", helo_data) < 0)
1382 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1383 ob->command_timeout))
1385 if (errno != 0 || buffer[0] == 0 || lmtp) goto RESPONSE_FAILED;
1392 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1397 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1399 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1400 ob->command_timeout)) goto RESPONSE_FAILED;
1403 /* Set IGNOREQUOTA if the response to LHLO specifies support and the
1404 lmtp_ignore_quota option was set. */
1406 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1407 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1408 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1410 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1413 tls_offered = esmtp &&
1414 pcre_exec(regex_STARTTLS, NULL, CS buffer, Ustrlen(buffer), 0,
1415 PCRE_EOPT, NULL, 0) >= 0;
1418 #ifndef DISABLE_PRDR
1419 prdr_offered = esmtp &&
1420 (pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(buffer), 0,
1421 PCRE_EOPT, NULL, 0) >= 0) &&
1422 (verify_check_this_host(&(ob->hosts_try_prdr), NULL, host->name,
1423 host->address, NULL) == OK);
1426 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1430 /* For continuing deliveries down the same channel, the socket is the standard
1431 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1432 below). Set up the pointer to where subsequent commands will be left, for
1433 error messages. Note that smtp_use_size and smtp_use_pipelining will have been
1434 set from the command line if they were set in the process that passed the
1439 inblock.sock = outblock.sock = fileno(stdin);
1440 smtp_command = big_buffer;
1441 host->port = port; /* Record the port that was used */
1444 /* If TLS is available on this connection, whether continued or not, attempt to
1445 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1446 send another EHLO - the server may give a different answer in secure mode. We
1447 use a separate buffer for reading the response to STARTTLS so that if it is
1448 negative, the original EHLO data is available for subsequent analysis, should
1449 the client not be required to use TLS. If the response is bad, copy the buffer
1450 for error analysis. */
1453 if (tls_offered && !suppress_tls &&
1454 verify_check_this_host(&(ob->hosts_avoid_tls), NULL, host->name,
1455 host->address, NULL) != OK)
1457 uschar buffer2[4096];
1458 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1461 /* If there is an I/O error, transmission of this message is deferred. If
1462 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1463 false, we also defer. However, if there is a temporary rejection of STARTTLS
1464 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1465 STARTTLS, we carry on. This means we will try to send the message in clear,
1466 unless the host is in hosts_require_tls (tested below). */
1468 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1469 ob->command_timeout))
1471 if (errno != 0 || buffer2[0] == 0 ||
1472 (buffer2[0] == '4' && !ob->tls_tempfail_tryclear))
1474 Ustrncpy(buffer, buffer2, sizeof(buffer));
1475 goto RESPONSE_FAILED;
1479 /* STARTTLS accepted: try to negotiate a TLS session. */
1484 int rc = tls_client_start(inblock.sock, host, addrlist, ob);
1486 /* TLS negotiation failed; give an error. From outside, this function may
1487 be called again to try in clear on a new connection, if the options permit
1488 it for this host. */
1492 save_errno = ERRNO_TLSFAILURE;
1493 message = US"failure while setting up TLS session";
1498 /* TLS session is set up */
1500 for (addr = addrlist; addr != NULL; addr = addr->next)
1502 if (addr->transport_return == PENDING_DEFER)
1504 addr->cipher = tls_out.cipher;
1505 addr->ourcert = tls_out.ourcert;
1506 addr->peercert = tls_out.peercert;
1507 addr->peerdn = tls_out.peerdn;
1508 addr->ocsp = tls_out.ocsp;
1514 /* if smtps, we'll have smtp_command set to something else; always safe to
1516 smtp_command = big_buffer;
1518 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1519 helo_data is null, we are dealing with a connection that was passed from
1520 another process, and so we won't have expanded helo_data above. We have to
1521 expand it here. $sending_ip_address and $sending_port are set up right at the
1522 start of the Exim process (in exim.c). */
1524 if (tls_out.active >= 0)
1527 if (helo_data == NULL)
1529 helo_data = expand_string(ob->helo_data);
1530 if (helo_data == NULL)
1532 uschar *message = string_sprintf("failed to expand helo_data: %s",
1533 expand_string_message);
1534 set_errno(addrlist, 0, message, DEFER, FALSE);
1540 /* For SMTPS we need to wait for the initial OK response. */
1543 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1544 ob->command_timeout)) goto RESPONSE_FAILED;
1548 greeting_cmd = "EHLO";
1551 greeting_cmd = "HELO";
1553 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1556 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1557 lmtp? "LHLO" : greeting_cmd, helo_data) < 0)
1559 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1560 ob->command_timeout))
1561 goto RESPONSE_FAILED;
1564 /* If the host is required to use a secure channel, ensure that we
1567 else if (verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
1568 host->address, NULL) == OK)
1570 save_errno = ERRNO_TLSREQUIRED;
1571 message = string_sprintf("a TLS session is required for %s [%s], but %s",
1572 host->name, host->address,
1573 tls_offered? "an attempt to start TLS failed" :
1574 "the server did not offer TLS support");
1579 /* If TLS is active, we have just started it up and re-done the EHLO command,
1580 so its response needs to be analyzed. If TLS is not active and this is a
1581 continued session down a previously-used socket, we haven't just done EHLO, so
1584 if (continue_hostname == NULL
1586 || tls_out.active >= 0
1590 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
1591 lmtp_ignore_quota option was set. */
1593 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1594 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1595 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1597 /* If the response to EHLO specified support for the SIZE parameter, note
1598 this, provided size_addition is non-negative. */
1600 smtp_use_size = esmtp && ob->size_addition >= 0 &&
1601 pcre_exec(regex_SIZE, NULL, CS buffer, Ustrlen(CS buffer), 0,
1602 PCRE_EOPT, NULL, 0) >= 0;
1604 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
1605 the current host, esmtp will be false, so PIPELINING can never be used. If
1606 the current host matches hosts_avoid_pipelining, don't do it. */
1608 smtp_use_pipelining = esmtp &&
1609 verify_check_this_host(&(ob->hosts_avoid_pipelining), NULL, host->name,
1610 host->address, NULL) != OK &&
1611 pcre_exec(regex_PIPELINING, NULL, CS buffer, Ustrlen(CS buffer), 0,
1612 PCRE_EOPT, NULL, 0) >= 0;
1614 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
1615 smtp_use_pipelining? "" : "not ");
1617 #ifndef DISABLE_PRDR
1618 prdr_offered = esmtp &&
1619 pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(CS buffer), 0,
1620 PCRE_EOPT, NULL, 0) >= 0 &&
1621 verify_check_this_host(&(ob->hosts_try_prdr), NULL, host->name,
1622 host->address, NULL) == OK;
1625 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1628 #ifdef EXPERIMENTAL_DSN
1629 /* Note if the server supports DSN */
1630 smtp_use_dsn = esmtp && pcre_exec(regex_DSN, NULL, CS buffer, (int)Ustrlen(CS buffer), 0,
1631 PCRE_EOPT, NULL, 0) >= 0;
1632 DEBUG(D_transport) debug_printf("use_dsn=%d\n", smtp_use_dsn);
1635 /* Note if the response to EHLO specifies support for the AUTH extension.
1636 If it has, check that this host is one we want to authenticate to, and do
1637 the business. The host name and address must be available when the
1638 authenticator's client driver is running. */
1640 switch (yield = smtp_auth(buffer, sizeof(buffer), addrlist, host,
1641 ob, esmtp, &inblock, &outblock))
1643 default: goto SEND_QUIT;
1645 case FAIL_SEND: goto SEND_FAILED;
1646 case FAIL: goto RESPONSE_FAILED;
1650 /* The setting up of the SMTP call is now complete. Any subsequent errors are
1651 message-specific. */
1655 /* If there is a filter command specified for this transport, we can now
1656 set it up. This cannot be done until the identify of the host is known. */
1658 if (tblock->filter_command != NULL)
1662 sprintf(CS buffer, "%.50s transport", tblock->name);
1663 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
1664 TRUE, DEFER, addrlist, buffer, NULL);
1665 transport_filter_timeout = tblock->filter_timeout;
1667 /* On failure, copy the error to all addresses, abandon the SMTP call, and
1672 set_errno(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
1680 /* For messages that have more than the maximum number of envelope recipients,
1681 we want to send several transactions down the same SMTP connection. (See
1682 comments in deliver.c as to how this reconciles, heuristically, with
1683 remote_max_parallel.) This optimization was added to Exim after the following
1684 code was already working. The simplest way to put it in without disturbing the
1685 code was to use a goto to jump back to this point when there is another
1686 transaction to handle. */
1689 sync_addr = first_addr;
1693 completed_address = FALSE;
1696 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
1697 qualification, send it, adding something to the message size to allow for
1698 imprecision and things that get added en route. Exim keeps the number of lines
1699 in a message, so we can give an accurate value for the original message, but we
1700 need some additional to handle added headers. (Double "." characters don't get
1701 included in the count.) */
1708 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
1712 #ifndef DISABLE_PRDR
1713 prdr_active = FALSE;
1716 for (addr = first_addr; addr; addr = addr->next)
1717 if (addr->transport_return == PENDING_DEFER)
1719 for (addr = addr->next; addr; addr = addr->next)
1720 if (addr->transport_return == PENDING_DEFER)
1721 { /* at least two recipients to send */
1723 sprintf(CS p, " PRDR"); p += 5;
1724 goto prdr_is_active;
1732 #ifdef EXPERIMENTAL_DSN
1733 /* check if all addresses have lasthop flag */
1734 /* do not send RET and ENVID if true */
1735 dsn_all_lasthop = TRUE;
1736 for (addr = first_addr;
1737 address_count < max_rcpt && addr != NULL;
1739 if ((addr->dsn_flags & rf_dsnlasthop) != 1)
1740 dsn_all_lasthop = FALSE;
1742 /* Add any DSN flags to the mail command */
1744 if ((smtp_use_dsn) && (dsn_all_lasthop == FALSE))
1746 if (dsn_ret == dsn_ret_hdrs)
1748 strcpy(p, " RET=HDRS");
1751 else if (dsn_ret == dsn_ret_full)
1753 strcpy(p, " RET=FULL");
1756 if (dsn_envid != NULL)
1758 string_format(p, sizeof(buffer) - (p-buffer), " ENVID=%s", dsn_envid);
1764 /* If an authenticated_sender override has been specified for this transport
1765 instance, expand it. If the expansion is forced to fail, and there was already
1766 an authenticated_sender for this message, the original value will be used.
1767 Other expansion failures are serious. An empty result is ignored, but there is
1768 otherwise no check - this feature is expected to be used with LMTP and other
1769 cases where non-standard addresses (e.g. without domains) might be required. */
1771 if (smtp_mail_auth_str(p, sizeof(buffer) - (p-buffer), addrlist, ob))
1774 /* From here until we send the DATA command, we can make use of PIPELINING
1775 if the server host supports it. The code has to be able to check the responses
1776 at any point, for when the buffer fills up, so we write it totally generally.
1777 When PIPELINING is off, each command written reports that it has flushed the
1780 pending_MAIL = TRUE; /* The block starts with MAIL */
1782 rc = smtp_write_command(&outblock, smtp_use_pipelining,
1783 "MAIL FROM:<%s>%s\r\n", return_path, buffer);
1784 mail_command = string_copy(big_buffer); /* Save for later error message */
1788 case -1: /* Transmission error */
1791 case +1: /* Block was sent */
1792 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1793 ob->command_timeout))
1795 if (errno == 0 && buffer[0] == '4')
1797 errno = ERRNO_MAIL4XX;
1798 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1800 goto RESPONSE_FAILED;
1802 pending_MAIL = FALSE;
1806 /* Pass over all the relevant recipient addresses for this host, which are the
1807 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
1808 several before we have to read the responses for those seen so far. This
1809 checking is done by a subroutine because it also needs to be done at the end.
1810 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
1811 the next one if not all are sent.
1813 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
1814 last address because we want to abort if any recipients have any kind of
1815 problem, temporary or permanent. We know that all recipient addresses will have
1816 the PENDING_DEFER status, because only one attempt is ever made, and we know
1817 that max_rcpt will be large, so all addresses will be done at once. */
1819 for (addr = first_addr;
1820 address_count < max_rcpt && addr != NULL;
1826 #ifdef EXPERIMENTAL_DSN
1828 addr->dsn_aware = dsn_support_yes;
1830 addr->dsn_aware = dsn_support_no;
1833 if (addr->transport_return != PENDING_DEFER) continue;
1836 no_flush = smtp_use_pipelining && (!mua_wrapper || addr->next != NULL);
1838 #ifdef EXPERIMENTAL_DSN
1839 /* Add any DSN flags to the rcpt command and add to the sent string */
1844 if ((smtp_use_dsn) && ((addr->dsn_flags & rf_dsnlasthop) != 1))
1846 if ((addr->dsn_flags & rf_dsnflags) != 0)
1850 strcpy(p, " NOTIFY=");
1852 for (i = 0; i < 4; i++)
1854 if ((addr->dsn_flags & rf_list[i]) != 0)
1856 if (!first) *p++ = ',';
1858 strcpy(p, rf_names[i]);
1864 if (addr->dsn_orcpt != NULL) {
1865 string_format(p, sizeof(buffer) - (p-buffer), " ORCPT=%s",
1873 /* Now send the RCPT command, and process outstanding responses when
1874 necessary. After a timeout on RCPT, we just end the function, leaving the
1875 yield as OK, because this error can often mean that there is a problem with
1876 just one address, so we don't want to delay the host. */
1878 #ifdef EXPERIMENTAL_DSN
1879 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s%s\r\n",
1880 transport_rcpt_address(addr, tblock->rcpt_include_affixes), igquotstr, buffer);
1882 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s\r\n",
1883 transport_rcpt_address(addr, tblock->rcpt_include_affixes), igquotstr);
1886 if (count < 0) goto SEND_FAILED;
1889 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
1890 &sync_addr, host, count, ob->address_retry_include_sender,
1891 pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
1894 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1895 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1898 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1899 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1900 case 0: /* No 2xx or 5xx, but no probs */
1903 case -1: goto END_OFF; /* Timeout on RCPT */
1904 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
1906 pending_MAIL = FALSE; /* Dealt with MAIL */
1908 } /* Loop for next address */
1910 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
1911 permanently or temporarily. We should have flushed and synced after the last
1916 address_item *badaddr;
1917 for (badaddr = first_addr; badaddr != NULL; badaddr = badaddr->next)
1919 if (badaddr->transport_return != PENDING_OK) break;
1921 if (badaddr != NULL)
1923 set_errno(addrlist, 0, badaddr->message, FAIL,
1924 testflag(badaddr, af_pass_message));
1929 /* If ok is TRUE, we know we have got at least one good recipient, and must now
1930 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
1931 have a good recipient buffered up if we are pipelining. We don't want to waste
1932 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
1933 are pipelining. The responses are all handled by sync_responses(). */
1935 if (ok || (smtp_use_pipelining && !mua_wrapper))
1937 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
1938 if (count < 0) goto SEND_FAILED;
1939 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
1940 host, count, ob->address_retry_include_sender, pending_MAIL,
1941 ok? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
1943 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1944 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1947 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1948 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1949 case 0: break; /* No 2xx or 5xx, but no probs */
1951 case -1: goto END_OFF; /* Timeout on RCPT */
1952 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
1956 /* Save the first address of the next batch. */
1960 /* If there were no good recipients (but otherwise there have been no
1961 problems), just set ok TRUE, since we have handled address-specific errors
1962 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
1963 for handling the SMTP dot-handling protocol, flagging to apply to headers as
1964 well as body. Set the appropriate timeout value to be used for each chunk.
1965 (Haven't been able to make it work using select() for writing yet.) */
1967 if (!ok) ok = TRUE; else
1969 sigalrm_seen = FALSE;
1970 transport_write_timeout = ob->data_timeout;
1971 smtp_command = US"sending data block"; /* For error messages */
1972 DEBUG(D_transport|D_v)
1973 debug_printf(" SMTP>> writing message and terminating \".\"\n");
1974 transport_count = 0;
1975 #ifndef DISABLE_DKIM
1976 ok = dkim_transport_write_message(addrlist, inblock.sock,
1977 topt_use_crlf | topt_end_dot | topt_escape_headers |
1978 (tblock->body_only? topt_no_headers : 0) |
1979 (tblock->headers_only? topt_no_body : 0) |
1980 (tblock->return_path_add? topt_add_return_path : 0) |
1981 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1982 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1983 0, /* No size limit */
1984 tblock->add_headers, tblock->remove_headers,
1985 US".", US"..", /* Escaping strings */
1986 tblock->rewrite_rules, tblock->rewrite_existflags,
1987 ob->dkim_private_key, ob->dkim_domain, ob->dkim_selector,
1988 ob->dkim_canon, ob->dkim_strict, ob->dkim_sign_headers
1991 ok = transport_write_message(addrlist, inblock.sock,
1992 topt_use_crlf | topt_end_dot | topt_escape_headers |
1993 (tblock->body_only? topt_no_headers : 0) |
1994 (tblock->headers_only? topt_no_body : 0) |
1995 (tblock->return_path_add? topt_add_return_path : 0) |
1996 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1997 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1998 0, /* No size limit */
1999 tblock->add_headers, tblock->remove_headers,
2000 US".", US"..", /* Escaping strings */
2001 tblock->rewrite_rules, tblock->rewrite_existflags);
2004 /* transport_write_message() uses write() because it is called from other
2005 places to write to non-sockets. This means that under some OS (e.g. Solaris)
2006 it can exit with "Broken pipe" as its error. This really means that the
2007 socket got closed at the far end. */
2009 transport_write_timeout = 0; /* for subsequent transports */
2011 /* Failure can either be some kind of I/O disaster (including timeout),
2012 or the failure of a transport filter or the expansion of added headers. */
2016 buffer[0] = 0; /* There hasn't been a response */
2017 goto RESPONSE_FAILED;
2020 /* We used to send the terminating "." explicitly here, but because of
2021 buffering effects at both ends of TCP/IP connections, you don't gain
2022 anything by keeping it separate, so it might as well go in the final
2023 data buffer for efficiency. This is now done by setting the topt_end_dot
2026 smtp_command = US"end of data";
2028 #ifndef DISABLE_PRDR
2029 /* For PRDR we optionally get a partial-responses warning
2030 * followed by the individual responses, before going on with
2031 * the overall response. If we don't get the warning then deal
2032 * with per non-PRDR. */
2035 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '3',
2037 if (!ok && errno == 0)
2040 case '2': prdr_active = FALSE;
2043 case '4': errno = ERRNO_DATA4XX;
2044 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2051 /* For non-PRDR SMTP, we now read a single response that applies to the
2052 whole message. If it is OK, then all the addresses have been delivered. */
2056 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2058 if (!ok && errno == 0 && buffer[0] == '4')
2060 errno = ERRNO_DATA4XX;
2061 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2065 /* For LMTP, we get back a response for every RCPT command that we sent;
2066 some may be accepted and some rejected. For those that get a response, their
2067 status is fixed; any that are accepted have been handed over, even if later
2068 responses crash - at least, that's how I read RFC 2033.
2070 If all went well, mark the recipient addresses as completed, record which
2071 host/IPaddress they were delivered to, and cut out RSET when sending another
2072 message down the same channel. Write the completed addresses to the journal
2073 now so that they are recorded in case there is a crash of hardware or
2074 software before the spool gets updated. Also record the final SMTP
2075 confirmation if needed (for SMTP only). */
2080 int delivery_time = (int)(time(NULL) - start_delivery_time);
2083 uschar *conf = NULL;
2086 /* Make a copy of the host if it is local to this invocation
2087 of the transport. */
2091 thost = store_get(sizeof(host_item));
2093 thost->name = string_copy(host->name);
2094 thost->address = string_copy(host->address);
2098 /* Set up confirmation if needed - applies only to SMTP */
2101 #ifndef EXPERIMENTAL_TPDA
2102 (log_extra_selector & LX_smtp_confirmation) != 0 &&
2107 uschar *s = string_printing(buffer);
2108 conf = (s == buffer)? (uschar *)string_copy(s) : s;
2111 /* Process all transported addresses - for LMTP or PRDR, read a status for
2114 for (addr = addrlist; addr != first_addr; addr = addr->next)
2116 if (addr->transport_return != PENDING_OK) continue;
2118 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
2119 remaining addresses. Otherwise, it's a return code for just the one
2120 address. For temporary errors, add a retry item for the address so that
2121 it doesn't get tried again too soon. */
2123 #ifndef DISABLE_PRDR
2124 if (lmtp || prdr_active)
2129 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2132 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
2133 addr->message = string_sprintf(
2134 #ifndef DISABLE_PRDR
2135 "%s error after %s: %s", prdr_active ? "PRDR":"LMTP",
2137 "LMTP error after %s: %s",
2139 big_buffer, string_printing(buffer));
2140 setflag(addr, af_pass_message); /* Allow message to go to user */
2141 if (buffer[0] == '5')
2142 addr->transport_return = FAIL;
2145 errno = ERRNO_DATA4XX;
2146 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2147 addr->transport_return = DEFER;
2148 #ifndef DISABLE_PRDR
2151 retry_add_item(addr, addr->address_retry_key, 0);
2155 completed_address = TRUE; /* NOW we can set this flag */
2156 if ((log_extra_selector & LX_smtp_confirmation) != 0)
2158 uschar *s = string_printing(buffer);
2159 conf = (s == buffer)? (uschar *)string_copy(s) : s;
2163 /* SMTP, or success return from LMTP for this address. Pass back the
2164 actual host that was used. */
2166 addr->transport_return = OK;
2167 addr->more_errno = delivery_time;
2168 addr->host_used = thost;
2169 addr->special_action = flag;
2170 addr->message = conf;
2171 #ifndef DISABLE_PRDR
2172 if (prdr_active) addr->flags |= af_prdr_used;
2176 #ifndef DISABLE_PRDR
2180 /* Update the journal. For homonymic addresses, use the base address plus
2181 the transport name. See lots of comments in deliver.c about the reasons
2182 for the complications when homonyms are involved. Just carry on after
2183 write error, as it may prove possible to update the spool file later. */
2185 if (testflag(addr, af_homonym))
2186 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2188 sprintf(CS buffer, "%.500s\n", addr->unique);
2190 DEBUG(D_deliver) debug_printf("journalling %s", buffer);
2191 len = Ustrlen(CS buffer);
2192 if (write(journal_fd, buffer, len) != len)
2193 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2194 "%s: %s", buffer, strerror(errno));
2198 #ifndef DISABLE_PRDR
2201 /* PRDR - get the final, overall response. For any non-success
2202 upgrade all the address statuses. */
2203 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2207 if(errno == 0 && buffer[0] == '4')
2209 errno = ERRNO_DATA4XX;
2210 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2212 for (addr = addrlist; addr != first_addr; addr = addr->next)
2213 if (buffer[0] == '5' || addr->transport_return == OK)
2214 addr->transport_return = PENDING_OK; /* allow set_errno action */
2215 goto RESPONSE_FAILED;
2218 /* Update the journal, or setup retry. */
2219 for (addr = addrlist; addr != first_addr; addr = addr->next)
2220 if (addr->transport_return == OK)
2222 if (testflag(addr, af_homonym))
2223 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2225 sprintf(CS buffer, "%.500s\n", addr->unique);
2227 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s", buffer);
2228 len = Ustrlen(CS buffer);
2229 if (write(journal_fd, buffer, len) != len)
2230 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2231 "%s: %s", buffer, strerror(errno));
2233 else if (addr->transport_return == DEFER)
2234 retry_add_item(addr, addr->address_retry_key, -2);
2238 /* Ensure the journal file is pushed out to disk. */
2240 if (EXIMfsync(journal_fd) < 0)
2241 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
2247 /* Handle general (not specific to one address) failures here. The value of ok
2248 is used to skip over this code on the falling through case. A timeout causes a
2249 deferral. Other errors may defer or fail according to the response code, and
2250 may set up a special errno value, e.g. after connection chopped, which is
2251 assumed if errno == 0 and there is no text in the buffer. If control reaches
2252 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
2253 the problem is not related to this specific message. */
2262 send_quit = check_response(host, &save_errno, addrlist->more_errno,
2263 buffer, &code, &message, &pass_message);
2269 message = US string_sprintf("send() to %s [%s] failed: %s",
2270 host->name, host->address, strerror(save_errno));
2274 /* This label is jumped to directly when a TLS negotiation has failed,
2275 or was not done for a host for which it is required. Values will be set
2276 in message and save_errno, and setting_up will always be true. Treat as
2277 a temporary error. */
2284 /* If the failure happened while setting up the call, see if the failure was
2285 a 5xx response (this will either be on connection, or following HELO - a 5xx
2286 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
2287 never going to accept them. For other errors during setting up (timeouts or
2288 whatever), defer all addresses, and yield DEFER, so that the host is not
2289 tried again for a while. */
2292 ok = FALSE; /* For when reached by GOTO */
2298 set_errno(addrlist, save_errno, message, FAIL, pass_message);
2302 set_errno(addrlist, save_errno, message, DEFER, pass_message);
2307 /* We want to handle timeouts after MAIL or "." and loss of connection after
2308 "." specially. They can indicate a problem with the sender address or with
2309 the contents of the message rather than a real error on the connection. These
2310 cases are treated in the same way as a 4xx response. This next bit of code
2311 does the classification. */
2322 message_error = TRUE;
2326 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
2327 Ustrncmp(smtp_command,"end ",4) == 0;
2330 case ERRNO_SMTPCLOSED:
2331 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
2335 message_error = FALSE;
2339 /* Handle the cases that are treated as message errors. These are:
2341 (a) negative response or timeout after MAIL
2342 (b) negative response after DATA
2343 (c) negative response or timeout or dropped connection after "."
2345 It won't be a negative response or timeout after RCPT, as that is dealt
2346 with separately above. The action in all cases is to set an appropriate
2347 error code for all the addresses, but to leave yield set to OK because the
2348 host itself has not failed. Of course, it might in practice have failed
2349 when we've had a timeout, but if so, we'll discover that at the next
2350 delivery attempt. For a temporary error, set the message_defer flag, and
2351 write to the logs for information if this is not the last host. The error
2352 for the last host will be logged as part of the address's log line. */
2356 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
2357 set_errno(addrlist, save_errno, message, (code == '5')? FAIL : DEFER,
2360 /* If there's an errno, the message contains just the identity of
2363 if (code != '5') /* Anything other than 5 is treated as temporary */
2366 message = US string_sprintf("%s: %s", message, strerror(save_errno));
2367 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
2368 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
2369 *message_defer = TRUE;
2373 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
2374 ".", or some other transportation error. We defer all addresses and yield
2375 DEFER, except for the case of failed add_headers expansion, or a transport
2376 filter failure, when the yield should be ERROR, to stop it trying other
2381 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
2382 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
2383 set_errno(addrlist, save_errno, message, DEFER, pass_message);
2389 /* If all has gone well, send_quit will be set TRUE, implying we can end the
2390 SMTP session tidily. However, if there were too many addresses to send in one
2391 message (indicated by first_addr being non-NULL) we want to carry on with the
2392 rest of them. Also, it is desirable to send more than one message down the SMTP
2393 connection if there are several waiting, provided we haven't already sent so
2394 many as to hit the configured limit. The function transport_check_waiting looks
2395 for a waiting message and returns its id. Then transport_pass_socket tries to
2396 set up a continued delivery by passing the socket on to another process. The
2397 variable send_rset is FALSE if a message has just been successfully transfered.
2399 If we are already sending down a continued channel, there may be further
2400 addresses not yet delivered that are aimed at the same host, but which have not
2401 been passed in this run of the transport. In this case, continue_more will be
2402 true, and all we should do is send RSET if necessary, and return, leaving the
2405 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
2406 do not want to continue with other messages down the same channel, because that
2407 can lead to looping between two or more messages, all with the same,
2408 temporarily failing address(es). [The retry information isn't updated yet, so
2409 new processes keep on trying.] We probably also don't want to try more of this
2410 message's addresses either.
2412 If we have started a TLS session, we have to end it before passing the
2413 connection to a new process. However, not all servers can handle this (Exim
2414 can), so we do not pass such a connection on if the host matches
2415 hosts_nopass_tls. */
2418 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
2419 "yield=%d first_address is %sNULL\n", ok, send_quit, send_rset,
2420 continue_more, yield, (first_addr == NULL)? "":"not ");
2422 if (completed_address && ok && send_quit)
2425 if (first_addr != NULL || continue_more ||
2427 (tls_out.active < 0 ||
2428 verify_check_this_host(&(ob->hosts_nopass_tls), NULL, host->name,
2429 host->address, NULL) != OK)
2431 transport_check_waiting(tblock->name, host->name,
2432 tblock->connection_max_messages, new_message_id, &more)
2440 if (! (ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
2442 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
2443 host->address, strerror(save_errno));
2446 else if (! (ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2447 ob->command_timeout)))
2450 send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
2454 DEBUG(D_transport) debug_printf("%s\n", msg);
2459 /* Either RSET was not needed, or it succeeded */
2463 if (first_addr != NULL) /* More addresses still to be sent */
2464 { /* in this run of the transport */
2465 continue_sequence++; /* Causes * in logging */
2468 if (continue_more) return yield; /* More addresses for another run */
2470 /* Pass the socket to a new Exim process. Before doing so, we must shut
2471 down TLS. Not all MTAs allow for the continuation of the SMTP session
2472 when TLS is shut down. We test for this by sending a new EHLO. If we
2473 don't get a good response, we don't attempt to pass the socket on. */
2476 if (tls_out.active >= 0)
2478 tls_close(FALSE, TRUE);
2482 ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
2483 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2484 ob->command_timeout);
2488 /* If the socket is successfully passed, we musn't send QUIT (or
2489 indeed anything!) from here. */
2491 if (ok && transport_pass_socket(tblock->name, host->name, host->address,
2492 new_message_id, inblock.sock))
2498 /* If RSET failed and there are addresses left, they get deferred. */
2500 else set_errno(first_addr, errno, msg, DEFER, FALSE);
2504 /* End off tidily with QUIT unless the connection has died or the socket has
2505 been passed to another process. There has been discussion on the net about what
2506 to do after sending QUIT. The wording of the RFC suggests that it is necessary
2507 to wait for a response, but on the other hand, there isn't anything one can do
2508 with an error response, other than log it. Exim used to do that. However,
2509 further discussion suggested that it is positively advantageous not to wait for
2510 the response, but to close the session immediately. This is supposed to move
2511 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
2512 load from the server. (Hosts that are both servers and clients may not see much
2513 difference, of course.) Further discussion indicated that this was safe to do
2514 on Unix systems which have decent implementations of TCP/IP that leave the
2515 connection around for a while (TIME_WAIT) after the application has gone away.
2516 This enables the response sent by the server to be properly ACKed rather than
2517 timed out, as can happen on broken TCP/IP implementations on other OS.
2519 This change is being made on 31-Jul-98. After over a year of trouble-free
2520 operation, the old commented-out code was removed on 17-Sep-99. */
2523 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2528 tls_close(FALSE, TRUE);
2531 /* Close the socket, and return the appropriate value, first setting
2532 works because the NULL setting is passed back to the calling process, and
2533 remote_max_parallel is forced to 1 when delivering over an existing connection,
2535 If all went well and continue_more is set, we shouldn't actually get here if
2536 there are further addresses, as the return above will be taken. However,
2537 writing RSET might have failed, or there may be other addresses whose hosts are
2538 specified in the transports, and therefore not visible at top level, in which
2539 case continue_more won't get set. */
2541 (void)close(inblock.sock);
2542 continue_transport = NULL;
2543 continue_hostname = NULL;
2550 /*************************************************
2551 * Closedown entry point *
2552 *************************************************/
2554 /* This function is called when exim is passed an open smtp channel
2555 from another incarnation, but the message which it has been asked
2556 to deliver no longer exists. The channel is on stdin.
2558 We might do fancy things like looking for another message to send down
2559 the channel, but if the one we sought has gone, it has probably been
2560 delivered by some other process that itself will seek further messages,
2561 so just close down our connection.
2563 Argument: pointer to the transport instance block
2568 smtp_transport_closedown(transport_instance *tblock)
2570 smtp_transport_options_block *ob =
2571 (smtp_transport_options_block *)(tblock->options_block);
2572 smtp_inblock inblock;
2573 smtp_outblock outblock;
2575 uschar inbuffer[4096];
2576 uschar outbuffer[16];
2578 inblock.sock = fileno(stdin);
2579 inblock.buffer = inbuffer;
2580 inblock.buffersize = sizeof(inbuffer);
2581 inblock.ptr = inbuffer;
2582 inblock.ptrend = inbuffer;
2584 outblock.sock = inblock.sock;
2585 outblock.buffersize = sizeof(outbuffer);
2586 outblock.buffer = outbuffer;
2587 outblock.ptr = outbuffer;
2588 outblock.cmd_count = 0;
2589 outblock.authenticating = FALSE;
2591 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2592 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2593 ob->command_timeout);
2594 (void)close(inblock.sock);
2599 /*************************************************
2600 * Prepare addresses for delivery *
2601 *************************************************/
2603 /* This function is called to flush out error settings from previous delivery
2604 attempts to other hosts. It also records whether we got here via an MX record
2605 or not in the more_errno field of the address. We are interested only in
2606 addresses that are still marked DEFER - others may have got delivered to a
2607 previously considered IP address. Set their status to PENDING_DEFER to indicate
2608 which ones are relevant this time.
2611 addrlist the list of addresses
2612 host the host we are delivering to
2614 Returns: the first address for this delivery
2617 static address_item *
2618 prepare_addresses(address_item *addrlist, host_item *host)
2620 address_item *first_addr = NULL;
2622 for (addr = addrlist; addr != NULL; addr = addr->next)
2624 if (addr->transport_return != DEFER) continue;
2625 if (first_addr == NULL) first_addr = addr;
2626 addr->transport_return = PENDING_DEFER;
2627 addr->basic_errno = 0;
2628 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
2629 addr->message = NULL;
2631 addr->cipher = NULL;
2632 addr->ourcert = NULL;
2633 addr->peercert = NULL;
2634 addr->peerdn = NULL;
2635 addr->ocsp = OCSP_NOT_REQ;
2643 /*************************************************
2644 * Main entry point *
2645 *************************************************/
2647 /* See local README for interface details. As this is a remote transport, it is
2648 given a chain of addresses to be delivered in one connection, if possible. It
2649 always returns TRUE, indicating that each address has its own independent
2650 status set, except if there is a setting up problem, in which case it returns
2654 smtp_transport_entry(
2655 transport_instance *tblock, /* data for this instantiation */
2656 address_item *addrlist) /* addresses we are working on */
2660 int hosts_defer = 0;
2662 int hosts_looked_up = 0;
2663 int hosts_retry = 0;
2664 int hosts_serial = 0;
2665 int hosts_total = 0;
2666 int total_hosts_tried = 0;
2668 BOOL expired = TRUE;
2669 BOOL continuing = continue_hostname != NULL;
2670 uschar *expanded_hosts = NULL;
2672 uschar *tid = string_sprintf("%s transport", tblock->name);
2673 smtp_transport_options_block *ob =
2674 (smtp_transport_options_block *)(tblock->options_block);
2675 host_item *hostlist = addrlist->host_list;
2676 host_item *host = NULL;
2680 debug_printf("%s transport entered\n", tblock->name);
2681 for (addr = addrlist; addr != NULL; addr = addr->next)
2682 debug_printf(" %s\n", addr->address);
2683 if (continuing) debug_printf("already connected to %s [%s]\n",
2684 continue_hostname, continue_host_address);
2687 /* Set the flag requesting that these hosts be added to the waiting
2688 database if the delivery fails temporarily or if we are running with
2689 queue_smtp or a 2-stage queue run. This gets unset for certain
2690 kinds of error, typically those that are specific to the message. */
2692 update_waiting = TRUE;
2694 /* If a host list is not defined for the addresses - they must all have the
2695 same one in order to be passed to a single transport - or if the transport has
2696 a host list with hosts_override set, use the host list supplied with the
2697 transport. It is an error for this not to exist. */
2699 if (hostlist == NULL || (ob->hosts_override && ob->hosts != NULL))
2701 if (ob->hosts == NULL)
2703 addrlist->message = string_sprintf("%s transport called with no hosts set",
2705 addrlist->transport_return = PANIC;
2706 return FALSE; /* Only top address has status */
2709 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
2712 /* If the transport's host list contains no '$' characters, and we are not
2713 randomizing, it is fixed and therefore a chain of hosts can be built once
2714 and for all, and remembered for subsequent use by other calls to this
2715 transport. If, on the other hand, the host list does contain '$', or we are
2716 randomizing its order, we have to rebuild it each time. In the fixed case,
2717 as the hosts string will never be used again, it doesn't matter that we
2718 replace all the : characters with zeros. */
2720 if (ob->hostlist == NULL)
2722 uschar *s = ob->hosts;
2724 if (Ustrchr(s, '$') != NULL)
2726 expanded_hosts = expand_string(s);
2727 if (expanded_hosts == NULL)
2729 addrlist->message = string_sprintf("failed to expand list of hosts "
2730 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
2731 addrlist->transport_return = search_find_defer? DEFER : PANIC;
2732 return FALSE; /* Only top address has status */
2734 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
2735 "\"%s\"\n", s, expanded_hosts);
2739 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
2741 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
2743 /* Check that the expansion yielded something useful. */
2744 if (hostlist == NULL)
2747 string_sprintf("%s transport has empty hosts setting", tblock->name);
2748 addrlist->transport_return = PANIC;
2749 return FALSE; /* Only top address has status */
2752 /* If there was no expansion of hosts, save the host list for
2755 if (expanded_hosts == NULL) ob->hostlist = hostlist;
2758 /* This is not the first time this transport has been run in this delivery;
2759 the host list was built previously. */
2761 else hostlist = ob->hostlist;
2764 /* The host list was supplied with the address. If hosts_randomize is set, we
2765 must sort it into a random order if it did not come from MX records and has not
2766 already been randomized (but don't bother if continuing down an existing
2769 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continuing)
2771 host_item *newlist = NULL;
2772 while (hostlist != NULL)
2774 host_item *h = hostlist;
2775 hostlist = hostlist->next;
2777 h->sort_key = random_number(100);
2779 if (newlist == NULL)
2784 else if (h->sort_key < newlist->sort_key)
2791 host_item *hh = newlist;
2792 while (hh->next != NULL)
2794 if (h->sort_key < hh->next->sort_key) break;
2802 hostlist = addrlist->host_list = newlist;
2806 /* Sort out the default port. */
2808 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
2811 /* For each host-plus-IP-address on the list:
2813 . If this is a continued delivery and the host isn't the one with the
2814 current connection, skip.
2816 . If the status is unusable (i.e. previously failed or retry checked), skip.
2818 . If no IP address set, get the address, either by turning the name into
2819 an address, calling gethostbyname if gethostbyname is on, or by calling
2820 the DNS. The DNS may yield multiple addresses, in which case insert the
2821 extra ones into the list.
2823 . Get the retry data if not previously obtained for this address and set the
2824 field which remembers the state of this address. Skip if the retry time is
2825 not reached. If not, remember whether retry data was found. The retry string
2826 contains both the name and the IP address.
2828 . Scan the list of addresses and mark those whose status is DEFER as
2829 PENDING_DEFER. These are the only ones that will be processed in this cycle
2832 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
2833 Some addresses may be successfully delivered, others may fail, and yet
2834 others may get temporary errors and so get marked DEFER.
2836 . The return from the delivery attempt is OK if a connection was made and a
2837 valid SMTP dialogue was completed. Otherwise it is DEFER.
2839 . If OK, add a "remove" retry item for this host/IPaddress, if any.
2841 . If fail to connect, or other defer state, add a retry item.
2843 . If there are any addresses whose status is still DEFER, carry on to the
2844 next host/IPaddress, unless we have tried the number of hosts given
2845 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
2846 there is some fancy logic for hosts_max_try that means its limit can be
2847 overstepped in some circumstances.
2849 If we get to the end of the list, all hosts have deferred at least one address,
2850 or not reached their retry times. If delay_after_cutoff is unset, it requests a
2851 delivery attempt to those hosts whose last try was before the arrival time of
2852 the current message. To cope with this, we have to go round the loop a second
2853 time. After that, set the status and error data for any addresses that haven't
2854 had it set already. */
2856 for (cutoff_retry = 0; expired &&
2857 cutoff_retry < ((ob->delay_after_cutoff)? 1 : 2);
2860 host_item *nexthost = NULL;
2861 int unexpired_hosts_tried = 0;
2863 for (host = hostlist;
2865 unexpired_hosts_tried < ob->hosts_max_try &&
2866 total_hosts_tried < ob->hosts_max_try_hardlimit;
2872 BOOL serialized = FALSE;
2873 BOOL host_is_expired = FALSE;
2874 BOOL message_defer = FALSE;
2875 BOOL ifchanges = FALSE;
2876 BOOL some_deferred = FALSE;
2877 address_item *first_addr = NULL;
2878 uschar *interface = NULL;
2879 uschar *retry_host_key = NULL;
2880 uschar *retry_message_key = NULL;
2881 uschar *serialize_key = NULL;
2883 /* Default next host is next host. :-) But this can vary if the
2884 hosts_max_try limit is hit (see below). It may also be reset if a host
2885 address is looked up here (in case the host was multihomed). */
2887 nexthost = host->next;
2889 /* If the address hasn't yet been obtained from the host name, look it up
2890 now, unless the host is already marked as unusable. If it is marked as
2891 unusable, it means that the router was unable to find its IP address (in
2892 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
2893 the lookup failed last time. We don't get this far if *all* MX records
2894 point to non-existent hosts; that is treated as a hard error.
2896 We can just skip this host entirely. When the hosts came from the router,
2897 the address will timeout based on the other host(s); when the address is
2898 looked up below, there is an explicit retry record added.
2900 Note that we mustn't skip unusable hosts if the address is not unset; they
2901 may be needed as expired hosts on the 2nd time round the cutoff loop. */
2903 if (host->address == NULL)
2905 int new_port, flags;
2907 uschar *canonical_name;
2909 if (host->status >= hstatus_unusable)
2911 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
2916 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
2918 /* The host name is permitted to have an attached port. Find it, and
2919 strip it from the name. Just remember it for now. */
2921 new_port = host_item_get_port(host);
2923 /* Count hosts looked up */
2927 /* Find by name if so configured, or if it's an IP address. We don't
2928 just copy the IP address, because we need the test-for-local to happen. */
2930 flags = HOST_FIND_BY_A;
2931 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
2932 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
2934 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
2935 rc = host_find_byname(host, NULL, flags, &canonical_name, TRUE);
2937 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
2938 ob->dnssec_request_domains, ob->dnssec_require_domains,
2939 &canonical_name, NULL);
2941 /* Update the host (and any additional blocks, resulting from
2942 multihoming) with a host-specific port, if any. */
2944 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
2946 /* Failure to find the host at this time (usually DNS temporary failure)
2947 is really a kind of routing failure rather than a transport failure.
2948 Therefore we add a retry item of the routing kind, not to stop us trying
2949 to look this name up here again, but to ensure the address gets timed
2950 out if the failures go on long enough. A complete failure at this point
2951 commonly points to a configuration error, but the best action is still
2952 to carry on for the next host. */
2954 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
2956 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
2958 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
2959 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
2960 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
2961 host->status = hstatus_unusable;
2963 for (addr = addrlist; addr != NULL; addr = addr->next)
2965 if (addr->transport_return != DEFER) continue;
2966 addr->basic_errno = ERRNO_UNKNOWNHOST;
2968 string_sprintf("failed to lookup IP address for %s", host->name);
2973 /* If the host is actually the local host, we may have a problem, or
2974 there may be some cunning configuration going on. In the problem case,
2975 log things and give up. The default transport status is already DEFER. */
2977 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
2979 for (addr = addrlist; addr != NULL; addr = addr->next)
2981 addr->basic_errno = 0;
2982 addr->message = string_sprintf("%s transport found host %s to be "
2983 "local", tblock->name, host->name);
2987 } /* End of block for IP address lookup */
2989 /* If this is a continued delivery, we are interested only in the host
2990 which matches the name of the existing open channel. The check is put
2991 here after the local host lookup, in case the name gets expanded as a
2992 result of the lookup. Set expired FALSE, to save the outer loop executing
2995 if (continuing && (Ustrcmp(continue_hostname, host->name) != 0 ||
2996 Ustrcmp(continue_host_address, host->address) != 0))
2999 continue; /* With next host */
3002 /* Reset the default next host in case a multihomed host whose addresses
3003 are not looked up till just above added to the host list. */
3005 nexthost = host->next;
3007 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
3008 domain is in queue_smtp_domains, we don't actually want to attempt any
3009 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
3010 there is a lookup defer in queue_smtp_domains, proceed as if the domain
3011 were not in it. We don't want to hold up all SMTP deliveries! Except when
3012 doing a two-stage queue run, don't do this if forcing. */
3014 if ((!deliver_force || queue_2stage) && (queue_smtp ||
3015 match_isinlist(addrlist->domain, &queue_smtp_domains, 0,
3016 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
3019 for (addr = addrlist; addr != NULL; addr = addr->next)
3021 if (addr->transport_return != DEFER) continue;
3022 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
3024 continue; /* With next host */
3027 /* Count hosts being considered - purely for an intelligent comment
3028 if none are usable. */
3032 /* Set $host and $host address now in case they are needed for the
3033 interface expansion or the serialize_hosts check; they remain set if an
3034 actual delivery happens. */
3036 deliver_host = host->name;
3037 deliver_host_address = host->address;
3038 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
3039 : host->dnssec == DS_NO ? US"no"
3042 /* Set up a string for adding to the retry key if the port number is not
3043 the standard SMTP port. A host may have its own port setting that overrides
3046 pistring = string_sprintf(":%d", (host->port == PORT_NONE)?
3048 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
3050 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
3051 string changes upon expansion, we must add it to the key that is used for
3052 retries, because connections to the same host from a different interface
3053 should be treated separately. */
3055 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET : AF_INET6;
3056 if (!smtp_get_interface(ob->interface, host_af, addrlist, &ifchanges,
3059 if (ifchanges) pistring = string_sprintf("%s/%s", pistring, interface);
3061 /* The first time round the outer loop, check the status of the host by
3062 inspecting the retry data. The second time round, we are interested only
3063 in expired hosts that haven't been tried since this message arrived. */
3065 if (cutoff_retry == 0)
3067 /* Ensure the status of the address is set by checking retry data if
3068 necessary. There maybe host-specific retry data (applicable to all
3069 messages) and also data for retries of a specific message at this host.
3070 If either of these retry records are actually read, the keys used are
3071 returned to save recomputing them later. */
3073 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
3074 ob->retry_include_ip_address, &retry_host_key, &retry_message_key);
3076 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
3077 (host->address == NULL)? US"" : host->address, pistring,
3078 (host->status == hstatus_usable)? "usable" :
3079 (host->status == hstatus_unusable)? "unusable" :
3080 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
3082 /* Skip this address if not usable at this time, noting if it wasn't
3083 actually expired, both locally and in the address. */
3085 switch (host->status)
3087 case hstatus_unusable:
3089 setflag(addrlist, af_retry_skipped);
3092 case hstatus_unusable_expired:
3095 case hwhy_retry: hosts_retry++; break;
3096 case hwhy_failed: hosts_fail++; break;
3097 case hwhy_deferred: hosts_defer++; break;
3100 /* If there was a retry message key, implying that previously there
3101 was a message-specific defer, we don't want to update the list of
3102 messages waiting for these hosts. */
3104 if (retry_message_key != NULL) update_waiting = FALSE;
3105 continue; /* With the next host or IP address */
3109 /* Second time round the loop: if the address is set but expired, and
3110 the message is newer than the last try, let it through. */
3114 if (host->address == NULL ||
3115 host->status != hstatus_unusable_expired ||
3116 host->last_try > received_time)
3119 debug_printf("trying expired host %s [%s]%s\n",
3120 host->name, host->address, pistring);
3121 host_is_expired = TRUE;
3124 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
3125 it remains TRUE only if all hosts are expired and none are actually tried.
3130 /* If this host is listed as one to which access must be serialized,
3131 see if another Exim process has a connection to it, and if so, skip
3132 this host. If not, update the database to record our connection to it
3133 and remember this for later deletion. Do not do any of this if we are
3134 sending the message down a pre-existing connection. */
3137 verify_check_this_host(&(ob->serialize_hosts), NULL, host->name,
3138 host->address, NULL) == OK)
3140 serialize_key = string_sprintf("host-serialize-%s", host->name);
3141 if (!enq_start(serialize_key))
3144 debug_printf("skipping host %s because another Exim process "
3145 "is connected to it\n", host->name);
3152 /* OK, we have an IP address that is not waiting for its retry time to
3153 arrive (it might be expired) OR (second time round the loop) we have an
3154 expired host that hasn't been tried since the message arrived. Have a go
3155 at delivering the message to it. First prepare the addresses by flushing
3156 out the result of previous attempts, and finding the first address that
3157 is still to be delivered. */
3159 first_addr = prepare_addresses(addrlist, host);
3161 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
3162 message_id, host->name, host->address, addrlist->address,
3163 (addrlist->next == NULL)? "" : ", ...");
3165 set_process_info("delivering %s to %s [%s] (%s%s)",
3166 message_id, host->name, host->address, addrlist->address,
3167 (addrlist->next == NULL)? "" : ", ...");
3169 /* This is not for real; don't do the delivery. If there are
3170 any remaining hosts, list them. */
3175 set_errno(addrlist, 0, NULL, OK, FALSE);
3176 for (addr = addrlist; addr != NULL; addr = addr->next)
3178 addr->host_used = host;
3179 addr->special_action = '*';
3180 addr->message = US"delivery bypassed by -N option";
3184 debug_printf("*** delivery by %s transport bypassed by -N option\n"
3185 "*** host and remaining hosts:\n", tblock->name);
3186 for (host2 = host; host2 != NULL; host2 = host2->next)
3187 debug_printf(" %s [%s]\n", host2->name,
3188 (host2->address == NULL)? US"unset" : host2->address);
3193 /* This is for real. If the host is expired, we don't count it for
3194 hosts_max_retry. This ensures that all hosts must expire before an address
3195 is timed out, unless hosts_max_try_hardlimit (which protects against
3196 lunatic DNS configurations) is reached.
3198 If the host is not expired and we are about to hit the hosts_max_retry
3199 limit, check to see if there is a subsequent hosts with a different MX
3200 value. If so, make that the next host, and don't count this one. This is a
3201 heuristic to make sure that different MXs do get tried. With a normal kind
3202 of retry rule, they would get tried anyway when the earlier hosts were
3203 delayed, but if the domain has a "retry every time" type of rule - as is
3204 often used for the the very large ISPs, that won't happen. */
3208 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
3212 debug_printf("hosts_max_try limit reached with this host\n");
3213 for (h = host; h != NULL; h = h->next)
3214 if (h->mx != host->mx) break;
3218 unexpired_hosts_tried--;
3219 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
3220 "and will be tried\n");
3224 /* Attempt the delivery. */
3226 total_hosts_tried++;
3227 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
3228 expanded_hosts != NULL, &message_defer, FALSE);
3231 OK => connection made, each address contains its result;
3232 message_defer is set for message-specific defers (when all
3233 recipients are marked defer)
3234 DEFER => there was a non-message-specific delivery problem;
3235 ERROR => there was a problem setting up the arguments for a filter,
3236 or there was a problem with expanding added headers
3239 /* If the result is not OK, there was a non-message-specific problem.
3240 If the result is DEFER, we need to write to the logs saying what happened
3241 for this particular host, except in the case of authentication and TLS
3242 failures, where the log has already been written. If all hosts defer a
3243 general message is written at the end. */
3245 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL &&
3246 first_addr->basic_errno != ERRNO_TLSFAILURE)
3247 write_logs(first_addr, host);
3249 #ifdef EXPERIMENTAL_TPDA
3251 tpda_deferred(ob, first_addr, host);
3254 /* If STARTTLS was accepted, but there was a failure in setting up the
3255 TLS session (usually a certificate screwup), and the host is not in
3256 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
3257 TLS forcibly turned off. We have to start from scratch with a new SMTP
3258 connection. That's why the retry is done from here, not from within
3259 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
3260 session, so the in-clear transmission after those errors, if permitted,
3261 happens inside smtp_deliver().] */
3264 if (rc == DEFER && first_addr->basic_errno == ERRNO_TLSFAILURE &&
3265 ob->tls_tempfail_tryclear &&
3266 verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
3267 host->address, NULL) != OK)
3269 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
3270 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
3271 first_addr = prepare_addresses(addrlist, host);
3272 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
3273 expanded_hosts != NULL, &message_defer, TRUE);
3274 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
3275 write_logs(first_addr, host);
3276 #ifdef EXPERIMENTAL_TPDA
3278 tpda_deferred(ob, first_addr, host);
3284 /* Delivery attempt finished */
3286 rs = (rc == OK)? US"OK" : (rc == DEFER)? US"DEFER" : (rc == ERROR)?
3289 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
3290 message_id, host->name, host->address, addrlist->address,
3291 (addrlist->next == NULL)? "" : " (& others)", rs);
3293 /* Release serialization if set up */
3295 if (serialized) enq_end(serialize_key);
3297 /* If the result is DEFER, or if a host retry record is known to exist, we
3298 need to add an item to the retry chain for updating the retry database
3299 at the end of delivery. We only need to add the item to the top address,
3300 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
3301 for any other delivery attempts using the same address. (It is copied into
3302 the unusable tree at the outer level, so even if different address blocks
3303 contain the same address, it still won't get tried again.) */
3305 if (rc == DEFER || retry_host_key != NULL)
3307 int delete_flag = (rc != DEFER)? rf_delete : 0;
3308 if (retry_host_key == NULL)
3310 retry_host_key = ob->retry_include_ip_address?
3311 string_sprintf("T:%S:%s%s", host->name, host->address, pistring) :
3312 string_sprintf("T:%S%s", host->name, pistring);
3315 /* If a delivery of another message over an existing SMTP connection
3316 yields DEFER, we do NOT set up retry data for the host. This covers the
3317 case when there are delays in routing the addresses in the second message
3318 that are so long that the server times out. This is alleviated by not
3319 routing addresses that previously had routing defers when handling an
3320 existing connection, but even so, this case may occur (e.g. if a
3321 previously happily routed address starts giving routing defers). If the
3322 host is genuinely down, another non-continued message delivery will
3323 notice it soon enough. */
3325 if (delete_flag != 0 || !continuing)
3326 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
3328 /* We may have tried an expired host, if its retry time has come; ensure
3329 the status reflects the expiry for the benefit of any other addresses. */
3333 host->status = (host_is_expired)?
3334 hstatus_unusable_expired : hstatus_unusable;
3335 host->why = hwhy_deferred;
3339 /* If message_defer is set (host was OK, but every recipient got deferred
3340 because of some message-specific problem), or if that had happened
3341 previously so that a message retry key exists, add an appropriate item
3342 to the retry chain. Note that if there was a message defer but now there is
3343 a host defer, the message defer record gets deleted. That seems perfectly
3344 reasonable. Also, stop the message from being remembered as waiting
3345 for specific hosts. */
3347 if (message_defer || retry_message_key != NULL)
3349 int delete_flag = message_defer? 0 : rf_delete;
3350 if (retry_message_key == NULL)
3352 retry_message_key = ob->retry_include_ip_address?
3353 string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
3355 string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
3357 retry_add_item(addrlist, retry_message_key,
3358 rf_message | rf_host | delete_flag);
3359 update_waiting = FALSE;
3362 /* Any return other than DEFER (that is, OK or ERROR) means that the
3363 addresses have got their final statuses filled in for this host. In the OK
3364 case, see if any of them are deferred. */
3368 for (addr = addrlist; addr != NULL; addr = addr->next)
3370 if (addr->transport_return == DEFER)
3372 some_deferred = TRUE;
3378 /* If no addresses deferred or the result was ERROR, return. We do this for
3379 ERROR because a failing filter set-up or add_headers expansion is likely to
3380 fail for any host we try. */
3382 if (rc == ERROR || (rc == OK && !some_deferred))
3384 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3385 return TRUE; /* Each address has its status */
3388 /* If the result was DEFER or some individual addresses deferred, let
3389 the loop run to try other hosts with the deferred addresses, except for the
3390 case when we were trying to deliver down an existing channel and failed.
3391 Don't try any other hosts in this case. */
3393 if (continuing) break;
3395 /* If the whole delivery, or some individual addresses, were deferred and
3396 there are more hosts that could be tried, do not count this host towards
3397 the hosts_max_try limit if the age of the message is greater than the
3398 maximum retry time for this host. This means we may try try all hosts,
3399 ignoring the limit, when messages have been around for some time. This is
3400 important because if we don't try all hosts, the address will never time
3401 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
3403 if ((rc == DEFER || some_deferred) && nexthost != NULL)
3406 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
3408 if (retry != NULL && retry->rules != NULL)
3410 retry_rule *last_rule;
3411 for (last_rule = retry->rules;
3412 last_rule->next != NULL;
3413 last_rule = last_rule->next);
3414 timedout = time(NULL) - received_time > last_rule->timeout;
3416 else timedout = TRUE; /* No rule => timed out */
3420 unexpired_hosts_tried--;
3421 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
3422 "hosts_max_try (message older than host's retry time)\n");
3425 } /* End of loop for trying multiple hosts. */
3427 /* This is the end of the loop that repeats iff expired is TRUE and
3428 ob->delay_after_cutoff is FALSE. The second time round we will
3429 try those hosts that haven't been tried since the message arrived. */
3433 debug_printf("all IP addresses skipped or deferred at least one address\n");
3434 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
3435 debug_printf("retrying IP addresses not tried since message arrived\n");
3440 /* Get here if all IP addresses are skipped or defer at least one address. In
3441 MUA wrapper mode, this will happen only for connection or other non-message-
3442 specific failures. Force the delivery status for all addresses to FAIL. */
3446 for (addr = addrlist; addr != NULL; addr = addr->next)
3447 addr->transport_return = FAIL;
3451 /* In the normal, non-wrapper case, add a standard message to each deferred
3452 address if there hasn't been an error, that is, if it hasn't actually been
3453 tried this time. The variable "expired" will be FALSE if any deliveries were
3454 actually tried, or if there was at least one host that was not expired. That
3455 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
3456 a delivery has been tried, an error code will be set, and the failing of the
3457 message is handled by the retry code later.
3459 If queue_smtp is set, or this transport was called to send a subsequent message
3460 down an existing TCP/IP connection, and something caused the host not to be
3461 found, we end up here, but can detect these cases and handle them specially. */
3463 for (addr = addrlist; addr != NULL; addr = addr->next)
3465 /* If host is not NULL, it means that we stopped processing the host list
3466 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
3467 means we need to behave as if some hosts were skipped because their retry
3468 time had not come. Specifically, this prevents the address from timing out.
3469 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
3470 hosts were tried. */
3474 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
3477 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
3478 "hosts were tried\n");
3483 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
3484 setflag(addr, af_retry_skipped);
3488 if (queue_smtp) /* no deliveries attempted */
3490 addr->transport_return = DEFER;
3491 addr->basic_errno = 0;
3492 addr->message = US"SMTP delivery explicitly queued";
3495 else if (addr->transport_return == DEFER &&
3496 (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0) &&
3497 addr->message == NULL)
3499 addr->basic_errno = ERRNO_HRETRY;
3500 if (continue_hostname != NULL)
3502 addr->message = US"no host found for existing SMTP connection";
3506 setflag(addr, af_pass_message); /* This is not a security risk */
3507 addr->message = (ob->delay_after_cutoff)?
3508 US"retry time not reached for any host after a long failure period" :
3509 US"all hosts have been failing for a long time and were last tried "
3510 "after this message arrived";
3512 /* If we are already using fallback hosts, or there are no fallback hosts
3513 defined, convert the result to FAIL to cause a bounce. */
3515 if (addr->host_list == addr->fallback_hosts ||
3516 addr->fallback_hosts == NULL)
3517 addr->transport_return = FAIL;
3521 if (hosts_retry == hosts_total)
3522 addr->message = US"retry time not reached for any host";
3523 else if (hosts_fail == hosts_total)
3524 addr->message = US"all host address lookups failed permanently";
3525 else if (hosts_defer == hosts_total)
3526 addr->message = US"all host address lookups failed temporarily";
3527 else if (hosts_serial == hosts_total)
3528 addr->message = US"connection limit reached for all hosts";
3529 else if (hosts_fail+hosts_defer == hosts_total)
3530 addr->message = US"all host address lookups failed";
3531 else addr->message = US"some host address lookups failed and retry time "
3532 "not reached for other hosts or connection limit reached";
3537 /* Update the database which keeps information about which messages are waiting
3538 for which hosts to become available. For some message-specific errors, the
3539 update_waiting flag is turned off because we don't want follow-on deliveries in
3540 those cases. If this transport instance is explicitly limited to one message
3541 per connection then follow-on deliveries are not possible and there's no need
3542 to create/update the per-transport wait-<transport_name> database. */
3544 if (update_waiting && tblock->connection_max_messages != 1)
3545 transport_update_waiting(hostlist, tblock->name);
3549 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3551 return TRUE; /* Each address has its status */
3556 /* End of transport/smtp.c */