1 /* $Cambridge: exim/src/src/transports/smtp.c,v 1.27 2006/10/09 14:36:25 ph10 Exp $ */
3 /*************************************************
4 * Exim - an Internet mail transport agent *
5 *************************************************/
7 /* Copyright (c) University of Cambridge 1995 - 2006 */
8 /* See the file NOTICE for conditions of use and distribution. */
14 #define PENDING_DEFER (PENDING + DEFER)
15 #define PENDING_OK (PENDING + OK)
18 /* Options specific to the smtp transport. This transport also supports LMTP
19 over TCP/IP. The options must be in alphabetic order (note that "_" comes
20 before the lower case letters). Some live in the transport_instance block so as
21 to be publicly visible; these are flagged with opt_public. */
23 optionlist smtp_transport_options[] = {
24 { "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) },
40 #ifdef EXPERIMENTAL_DOMAINKEYS
41 { "dk_canon", opt_stringptr,
42 (void *)offsetof(smtp_transport_options_block, dk_canon) },
43 { "dk_domain", opt_stringptr,
44 (void *)offsetof(smtp_transport_options_block, dk_domain) },
45 { "dk_headers", opt_stringptr,
46 (void *)offsetof(smtp_transport_options_block, dk_headers) },
47 { "dk_private_key", opt_stringptr,
48 (void *)offsetof(smtp_transport_options_block, dk_private_key) },
49 { "dk_selector", opt_stringptr,
50 (void *)offsetof(smtp_transport_options_block, dk_selector) },
51 { "dk_strict", opt_stringptr,
52 (void *)offsetof(smtp_transport_options_block, dk_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 { "fallback_hosts", opt_stringptr,
59 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
60 { "final_timeout", opt_time,
61 (void *)offsetof(smtp_transport_options_block, final_timeout) },
62 { "gethostbyname", opt_bool,
63 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
64 { "helo_data", opt_stringptr,
65 (void *)offsetof(smtp_transport_options_block, helo_data) },
66 { "hosts", opt_stringptr,
67 (void *)offsetof(smtp_transport_options_block, hosts) },
68 { "hosts_avoid_esmtp", opt_stringptr,
69 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
71 { "hosts_avoid_tls", opt_stringptr,
72 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
74 { "hosts_max_try", opt_int,
75 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
76 { "hosts_max_try_hardlimit", opt_int,
77 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
79 { "hosts_nopass_tls", opt_stringptr,
80 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
82 { "hosts_override", opt_bool,
83 (void *)offsetof(smtp_transport_options_block, hosts_override) },
84 { "hosts_randomize", opt_bool,
85 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
86 { "hosts_require_auth", opt_stringptr,
87 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
89 { "hosts_require_tls", opt_stringptr,
90 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
92 { "hosts_try_auth", opt_stringptr,
93 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
94 { "interface", opt_stringptr,
95 (void *)offsetof(smtp_transport_options_block, interface) },
96 { "keepalive", opt_bool,
97 (void *)offsetof(smtp_transport_options_block, keepalive) },
98 { "lmtp_ignore_quota", opt_bool,
99 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
100 { "max_rcpt", opt_int | opt_public,
101 (void *)offsetof(transport_instance, max_addresses) },
102 { "multi_domain", opt_bool | opt_public,
103 (void *)offsetof(transport_instance, multi_domain) },
104 { "port", opt_stringptr,
105 (void *)offsetof(smtp_transport_options_block, port) },
106 { "protocol", opt_stringptr,
107 (void *)offsetof(smtp_transport_options_block, protocol) },
108 { "retry_include_ip_address", opt_bool,
109 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
110 { "serialize_hosts", opt_stringptr,
111 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
112 { "size_addition", opt_int,
113 (void *)offsetof(smtp_transport_options_block, size_addition) }
115 ,{ "tls_certificate", opt_stringptr,
116 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
117 { "tls_crl", opt_stringptr,
118 (void *)offsetof(smtp_transport_options_block, tls_crl) },
119 { "tls_privatekey", opt_stringptr,
120 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
121 { "tls_require_ciphers", opt_stringptr,
122 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
123 { "tls_tempfail_tryclear", opt_bool,
124 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
125 { "tls_verify_certificates", opt_stringptr,
126 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) }
130 /* Size of the options list. An extern variable has to be used so that its
131 address can appear in the tables drtables.c. */
133 int smtp_transport_options_count =
134 sizeof(smtp_transport_options)/sizeof(optionlist);
136 /* Default private options block for the smtp transport. */
138 smtp_transport_options_block smtp_transport_option_defaults = {
140 NULL, /* fallback_hosts */
142 NULL, /* fallback_hostlist */
143 NULL, /* authenticated_sender */
144 US"$primary_hostname", /* helo_data */
145 NULL, /* interface */
147 US"smtp", /* protocol */
148 NULL, /* serialize_hosts */
149 NULL, /* hosts_try_auth */
150 NULL, /* hosts_require_auth */
151 NULL, /* hosts_require_tls */
152 NULL, /* hosts_avoid_tls */
153 NULL, /* hosts_avoid_esmtp */
154 NULL, /* hosts_nopass_tls */
155 5*60, /* command_timeout */
156 5*60, /* connect_timeout; shorter system default overrides */
157 5*60, /* data timeout */
158 10*60, /* final timeout */
159 1024, /* size_addition */
160 5, /* hosts_max_try */
161 50, /* hosts_max_try_hardlimit */
162 FALSE, /* allow_localhost */
163 FALSE, /* authenticated_sender_force */
164 FALSE, /* gethostbyname */
165 TRUE, /* dns_qualify_single */
166 FALSE, /* dns_search_parents */
167 TRUE, /* delay_after_cutoff */
168 FALSE, /* hosts_override */
169 FALSE, /* hosts_randomize */
170 TRUE, /* keepalive */
171 FALSE, /* lmtp_ignore_quota */
172 TRUE /* retry_include_ip_address */
174 ,NULL, /* tls_certificate */
176 NULL, /* tls_privatekey */
177 NULL, /* tls_require_ciphers */
178 NULL, /* tls_verify_certificates */
179 TRUE /* tls_tempfail_tryclear */
181 #ifdef EXPERIMENTAL_DOMAINKEYS
182 ,NULL, /* dk_canon */
183 NULL, /* dk_domain */
184 NULL, /* dk_headers */
185 NULL, /* dk_private_key */
186 NULL, /* dk_selector */
194 static uschar *smtp_command; /* Points to last cmd for error messages */
195 static uschar *mail_command; /* Points to MAIL cmd for error messages */
198 /*************************************************
199 * Setup entry point *
200 *************************************************/
202 /* This function is called when the transport is about to be used,
203 but before running it in a sub-process. It is used for two things:
205 (1) To set the fallback host list in addresses, when delivering.
206 (2) To pass back the interface, port, protocol, and other options, for use
207 during callout verification.
210 tblock pointer to the transport instance block
211 addrlist list of addresses about to be transported
212 tf if not NULL, pointer to block in which to return options
213 uid the uid that will be set (not used)
214 gid the gid that will be set (not used)
215 errmsg place for error message (not used)
217 Returns: OK always (FAIL, DEFER not used)
221 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
222 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
224 smtp_transport_options_block *ob =
225 (smtp_transport_options_block *)(tblock->options_block);
227 errmsg = errmsg; /* Keep picky compilers happy */
231 /* Pass back options if required. This interface is getting very messy. */
235 tf->interface = ob->interface;
237 tf->protocol = ob->protocol;
238 tf->hosts = ob->hosts;
239 tf->hosts_override = ob->hosts_override;
240 tf->hosts_randomize = ob->hosts_randomize;
241 tf->gethostbyname = ob->gethostbyname;
242 tf->qualify_single = ob->dns_qualify_single;
243 tf->search_parents = ob->dns_search_parents;
244 tf->helo_data = ob->helo_data;
247 /* Set the fallback host list for all the addresses that don't have fallback
248 host lists, provided that the local host wasn't present in the original host
251 if (!testflag(addrlist, af_local_host_removed))
253 for (; addrlist != NULL; addrlist = addrlist->next)
254 if (addrlist->fallback_hosts == NULL)
255 addrlist->fallback_hosts = ob->fallback_hostlist;
263 /*************************************************
264 * Initialization entry point *
265 *************************************************/
267 /* Called for each instance, after its options have been read, to
268 enable consistency checks to be done, or anything else that needs
271 Argument: pointer to the transport instance block
276 smtp_transport_init(transport_instance *tblock)
278 smtp_transport_options_block *ob =
279 (smtp_transport_options_block *)(tblock->options_block);
281 /* Retry_use_local_part defaults FALSE if unset */
283 if (tblock->retry_use_local_part == TRUE_UNSET)
284 tblock->retry_use_local_part = FALSE;
286 /* Set the default port according to the protocol */
288 if (ob->port == NULL)
289 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" : US"smtp";
291 /* Set up the setup entry point, to be called before subprocesses for this
294 tblock->setup = smtp_transport_setup;
296 /* Complain if any of the timeouts are zero. */
298 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
299 ob->final_timeout <= 0)
300 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
301 "command, data, or final timeout value is zero for %s transport",
304 /* If hosts_override is set and there are local hosts, set the global
305 flag that stops verify from showing router hosts. */
307 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
309 /* If there are any fallback hosts listed, build a chain of host items
310 for them, but do not do any lookups at this time. */
312 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
319 /*************************************************
320 * Set delivery info into all active addresses *
321 *************************************************/
323 /* Only addresses whose status is >= PENDING are relevant. A lesser
324 status means that an address is not currently being processed.
327 addrlist points to a chain of addresses
328 errno_value to put in each address's errno field
329 msg to put in each address's message field
330 rc to put in each address's transport_return field
331 pass_message if TRUE, set the "pass message" flag in the address
333 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
334 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
335 this particular type of timeout.
341 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
346 if (errno_value == ERRNO_CONNECTTIMEOUT)
348 errno_value = ETIMEDOUT;
349 orvalue = RTEF_CTOUT;
351 for (addr = addrlist; addr != NULL; addr = addr->next)
353 if (addr->transport_return < PENDING) continue;
354 addr->basic_errno = errno_value;
355 addr->more_errno |= orvalue;
359 if (pass_message) setflag(addr, af_pass_message);
361 addr->transport_return = rc;
367 /*************************************************
368 * Check an SMTP response *
369 *************************************************/
371 /* This function is given an errno code and the SMTP response buffer
372 to analyse, together with the host identification for generating messages. It
373 sets an appropriate message and puts the first digit of the response code into
374 the yield variable. If no response was actually read, a suitable digit is
378 host the current host, to get its name for messages
379 errno_value pointer to the errno value
380 more_errno from the top address for use with ERRNO_FILTER_FAIL
381 buffer the SMTP response buffer
382 yield where to put a one-digit SMTP response code
383 message where to put an errror message
384 pass_message set TRUE if message is an SMTP response
386 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
389 static BOOL check_response(host_item *host, int *errno_value, int more_errno,
390 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
394 if (smtp_use_pipelining &&
395 (Ustrcmp(smtp_command, "MAIL") == 0 ||
396 Ustrcmp(smtp_command, "RCPT") == 0 ||
397 Ustrcmp(smtp_command, "DATA") == 0))
400 *yield = '4'; /* Default setting is to give a temporary error */
402 /* Handle response timeout */
404 if (*errno_value == ETIMEDOUT)
406 *message = US string_sprintf("SMTP timeout while connected to %s [%s] "
407 "after %s%s", host->name, host->address, pl, smtp_command);
408 if (transport_count > 0)
409 *message = US string_sprintf("%s (%d bytes written)", *message,
414 /* Handle malformed SMTP response */
416 if (*errno_value == ERRNO_SMTPFORMAT)
418 uschar *malfresp = string_printing(buffer);
419 while (isspace(*malfresp)) malfresp++;
421 *message = string_sprintf("Malformed SMTP reply (an empty line) from "
422 "%s [%s] in response to %s%s", host->name, host->address, pl,
425 *message = string_sprintf("Malformed SMTP reply from %s [%s] in response "
426 "to %s%s: %s", host->name, host->address, pl, smtp_command, malfresp);
430 /* Handle a failed filter process error; can't send QUIT as we mustn't
433 if (*errno_value == ERRNO_FILTER_FAIL)
435 *message = US string_sprintf("transport filter process failed (%d)%s",
437 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
441 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
444 if (*errno_value == ERRNO_CHHEADER_FAIL)
447 US string_sprintf("failed to expand headers_add or headers_remove: %s",
448 expand_string_message);
452 /* Handle failure to write a complete data block */
454 if (*errno_value == ERRNO_WRITEINCOMPLETE)
456 *message = US string_sprintf("failed to write a data block");
460 /* Handle error responses from the remote mailer. */
464 uschar *s = string_printing(buffer);
465 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
466 "host %s [%s]: %s", pl, smtp_command, host->name, host->address, s);
467 *pass_message = TRUE;
472 /* No data was read. If there is no errno, this must be the EOF (i.e.
473 connection closed) case, which causes deferral. An explicit connection reset
474 error has the same effect. Otherwise, put the host's identity in the message,
475 leaving the errno value to be interpreted as well. In all cases, we have to
476 assume the connection is now dead. */
478 if (*errno_value == 0 || *errno_value == ECONNRESET)
480 *errno_value = ERRNO_SMTPCLOSED;
481 *message = US string_sprintf("Remote host %s [%s] closed connection "
482 "in response to %s%s", host->name, host->address, pl, smtp_command);
484 else *message = US string_sprintf("%s [%s]", host->name, host->address);
491 /*************************************************
492 * Write error message to logs *
493 *************************************************/
495 /* This writes to the main log and to the message log.
498 addr the address item containing error information
499 host the current host
505 write_logs(address_item *addr, host_item *host)
507 if (addr->message != NULL)
509 uschar *message = addr->message;
510 if (addr->basic_errno > 0)
511 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
512 log_write(0, LOG_MAIN, "%s", message);
513 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
518 ((log_extra_selector & LX_outgoing_port) != 0)?
519 string_sprintf("%s [%s]:%d", host->name, host->address,
520 (host->port == PORT_NONE)? 25 : host->port)
522 string_sprintf("%s [%s]", host->name, host->address);
523 log_write(0, LOG_MAIN, "%s %s", msg, strerror(addr->basic_errno));
524 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), msg,
525 strerror(addr->basic_errno));
531 /*************************************************
532 * Synchronize SMTP responses *
533 *************************************************/
535 /* This function is called from smtp_deliver() to receive SMTP responses from
536 the server, and match them up with the commands to which they relate. When
537 PIPELINING is not in use, this function is called after every command, and is
538 therefore somewhat over-engineered, but it is simpler to use a single scheme
539 that works both with and without PIPELINING instead of having two separate sets
542 The set of commands that are buffered up with pipelining may start with MAIL
543 and may end with DATA; in between are RCPT commands that correspond to the
544 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
545 etc.) are never buffered.
547 Errors after MAIL or DATA abort the whole process leaving the response in the
548 buffer. After MAIL, pending responses are flushed, and the original command is
549 re-instated in big_buffer for error messages. For RCPT commands, the remote is
550 permitted to reject some recipient addresses while accepting others. However
551 certain errors clearly abort the whole process. Set the value in
552 transport_return to PENDING_OK if the address is accepted. If there is a
553 subsequent general error, it will get reset accordingly. If not, it will get
554 converted to OK at the end.
557 addrlist the complete address list
558 include_affixes TRUE if affixes include in RCPT
559 sync_addr ptr to the ptr of the one to start scanning at (updated)
560 host the host we are connected to
561 count the number of responses to read
562 pending_MAIL true if the first response is for MAIL
563 pending_DATA 0 if last command sent was not DATA
564 +1 if previously had a good recipient
565 -1 if not previously had a good recipient
566 inblock incoming SMTP block
567 timeout timeout value
568 buffer buffer for reading response
569 buffsize size of buffer
571 Returns: 3 if at least one address had 2xx and one had 5xx
572 2 if at least one address had 5xx but none had 2xx
573 1 if at least one host had a 2xx response, but none had 5xx
574 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
575 -1 timeout while reading RCPT response
576 -2 I/O or other non-response error for RCPT
577 -3 DATA or MAIL failed - errno and buffer set
581 sync_responses(address_item *addrlist, BOOL include_affixes,
582 address_item **sync_addr, host_item *host, int count, BOOL pending_MAIL,
583 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
586 address_item *addr = *sync_addr;
589 /* Handle the response for a MAIL command. On error, reinstate the original
590 command in big_buffer for error message use, and flush any further pending
591 responses before returning, except after I/O errors and timeouts. */
596 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
598 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
599 if (errno == 0 && buffer[0] != 0)
601 uschar flushbuffer[4096];
603 if (buffer[0] == '4')
605 save_errno = ERRNO_MAIL4XX;
606 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
610 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
612 && (errno != 0 || flushbuffer[0] == 0))
621 if (pending_DATA) count--; /* Number of RCPT responses to come */
623 /* Read and handle the required number of RCPT responses, matching each one up
624 with an address by scanning for the next address whose status is PENDING_DEFER.
629 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
631 /* The address was accepted */
633 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
636 addr->transport_return = PENDING_OK;
638 /* If af_dr_retry_exists is set, there was a routing delay on this address;
639 ensure that any address-specific retry record is expunged. */
641 if (testflag(addr, af_dr_retry_exists))
642 retry_add_item(addr, addr->address_retry_key, rf_delete);
645 /* Timeout while reading the response */
647 else if (errno == ETIMEDOUT)
649 int save_errno = errno;
650 uschar *message = string_sprintf("SMTP timeout while connected to %s [%s] "
651 "after RCPT TO:<%s>", host->name, host->address,
652 transport_rcpt_address(addr, include_affixes));
653 set_errno(addrlist, save_errno, message, DEFER, FALSE);
654 retry_add_item(addr, addr->address_retry_key, 0);
655 host->update_waiting = FALSE;
659 /* Handle other errors in obtaining an SMTP response by returning -1. This
660 will cause all the addresses to be deferred. Restore the SMTP command in
661 big_buffer for which we are checking the response, so the error message
664 else if (errno != 0 || buffer[0] == 0)
666 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
667 transport_rcpt_address(addr, include_affixes));
671 /* Handle SMTP permanent and temporary response codes. */
676 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
677 "host %s [%s]: %s", transport_rcpt_address(addr, include_affixes),
678 host->name, host->address, string_printing(buffer));
679 setflag(addr, af_pass_message);
680 deliver_msglog("%s %s\n", tod_stamp(tod_log), addr->message);
682 /* The response was 5xx */
684 if (buffer[0] == '5')
686 addr->transport_return = FAIL;
690 /* The response was 4xx */
694 addr->transport_return = DEFER;
695 addr->basic_errno = ERRNO_RCPT4XX;
696 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
698 /* Log temporary errors if there are more hosts to be tried. */
700 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", addr->message);
702 /* Do not put this message on the list of those waiting for this host,
703 as otherwise it is likely to be tried too often. */
705 host->update_waiting = FALSE;
707 /* Add a retry item for the address so that it doesn't get tried
710 retry_add_item(addr, addr->address_retry_key, 0);
713 } /* Loop for next RCPT response */
715 /* Update where to start at for the next block of responses, unless we
716 have already handled all the addresses. */
718 if (addr != NULL) *sync_addr = addr->next;
720 /* Handle a response to DATA. If we have not had any good recipients, either
721 previously or in this block, the response is ignored. */
723 if (pending_DATA != 0 &&
724 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
729 if (pending_DATA > 0 || (yield & 1) != 0)
731 if (errno == 0 && buffer[0] == '4')
733 errno = ERRNO_DATA4XX;
734 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
738 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
739 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
740 "is in use and there were no good recipients\n", msg);
743 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
744 present) received 3xx. If any RCPTs were handled and yielded anything other
745 than 4xx, yield will be set non-zero. */
752 /*************************************************
753 * Deliver address list to given host *
754 *************************************************/
756 /* If continue_hostname is not null, we get here only when continuing to
757 deliver down an existing channel. The channel was passed as the standard
760 Otherwise, we have to make a connection to the remote host, and do the
761 initial protocol exchange.
763 When running as an MUA wrapper, if the sender or any recipient is rejected,
764 temporarily or permanently, we force failure for all recipients.
767 addrlist chain of potential addresses to deliver; only those whose
768 transport_return field is set to PENDING_DEFER are currently
769 being processed; others should be skipped - they have either
770 been delivered to an earlier host or IP address, or been
771 failed by one of them.
772 host host to deliver to
773 host_af AF_INET or AF_INET6
774 port default TCP/IP port to use, in host byte order
775 interface interface to bind to, or NULL
776 tblock transport instance block
777 copy_host TRUE if host set in addr->host_used must be copied, because
778 it is specific to this call of the transport
779 message_defer set TRUE if yield is OK, but all addresses were deferred
780 because of a non-recipient, non-host failure, that is, a
781 4xx response to MAIL FROM, DATA, or ".". This is a defer
782 that is specific to the message.
783 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
784 a second attempt after TLS initialization fails
786 Returns: OK - the connection was made and the delivery attempted;
787 the result for each address is in its data block.
788 DEFER - the connection could not be made, or something failed
789 while setting up the SMTP session, or there was a
790 non-message-specific error, such as a timeout.
791 ERROR - a filter command is specified for this transport,
792 and there was a problem setting it up; OR helo_data
793 or add_headers or authenticated_sender is specified
794 for this transport, and the string failed to expand
798 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
799 uschar *interface, transport_instance *tblock, BOOL copy_host,
800 BOOL *message_defer, BOOL suppress_tls)
803 address_item *sync_addr;
804 address_item *first_addr = addrlist;
809 time_t start_delivery_time = time(NULL);
810 smtp_transport_options_block *ob =
811 (smtp_transport_options_block *)(tblock->options_block);
812 BOOL lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
814 BOOL send_rset = TRUE;
815 BOOL send_quit = TRUE;
816 BOOL setting_up = TRUE;
817 BOOL completed_address = FALSE;
820 BOOL pass_message = FALSE;
821 smtp_inblock inblock;
822 smtp_outblock outblock;
823 int max_rcpt = tblock->max_addresses;
824 uschar *igquotstr = US"";
825 uschar *local_authenticated_sender = authenticated_sender;
827 uschar *message = NULL;
828 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
831 uschar inbuffer[4096];
832 uschar outbuffer[1024];
834 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
836 *message_defer = FALSE;
837 smtp_command = US"initial connection";
838 if (max_rcpt == 0) max_rcpt = 999999;
840 /* Set up the buffer for reading SMTP response packets. */
842 inblock.buffer = inbuffer;
843 inblock.buffersize = sizeof(inbuffer);
844 inblock.ptr = inbuffer;
845 inblock.ptrend = inbuffer;
847 /* Set up the buffer for holding SMTP commands while pipelining */
849 outblock.buffer = outbuffer;
850 outblock.buffersize = sizeof(outbuffer);
851 outblock.ptr = outbuffer;
852 outblock.cmd_count = 0;
853 outblock.authenticating = FALSE;
855 /* Expand the greeting message */
857 helo_data = expand_string(ob->helo_data);
858 if (helo_data == NULL)
860 uschar *message = string_sprintf("failed to expand helo_data: %s",
861 expand_string_message);
862 set_errno(addrlist, 0, message, DEFER, FALSE);
866 /* If an authenticated_sender override has been specified for this transport
867 instance, expand it. If the expansion is forced to fail, and there was already
868 an authenticated_sender for this message, the original value will be used.
869 Other expansion failures are serious. An empty result is ignored, but there is
870 otherwise no check - this feature is expected to be used with LMTP and other
871 cases where non-standard addresses (e.g. without domains) might be required. */
873 if (ob->authenticated_sender != NULL)
875 uschar *new = expand_string(ob->authenticated_sender);
878 if (!expand_string_forcedfail)
880 uschar *message = string_sprintf("failed to expand "
881 "authenticated_sender: %s", expand_string_message);
882 set_errno(addrlist, 0, message, DEFER, FALSE);
886 else if (new[0] != 0) local_authenticated_sender = new;
889 /* Make a connection to the host if this isn't a continued delivery, and handle
890 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
891 specially so they can be identified for retries. */
893 if (continue_hostname == NULL)
895 inblock.sock = outblock.sock =
896 smtp_connect(host, host_af, port, interface, ob->connect_timeout,
898 if (inblock.sock < 0)
900 set_errno(addrlist, (errno == ETIMEDOUT)? ERRNO_CONNECTTIMEOUT : errno,
905 /* The first thing is to wait for an initial OK response. The dreaded "goto"
906 is nevertheless a reasonably clean way of programming this kind of logic,
907 where you want to escape on any error. */
909 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
910 ob->command_timeout)) goto RESPONSE_FAILED;
912 /** Debugging without sending a message
913 addrlist->transport_return = DEFER;
917 /* Errors that occur after this point follow an SMTP command, which is
918 left in big_buffer by smtp_write_command() for use in error messages. */
920 smtp_command = big_buffer;
922 /* Tell the remote who we are...
924 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
925 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
926 greeting is of this form. The assumption was that the far end supports it
927 properly... but experience shows that there are some that give 5xx responses,
928 even though the banner includes "ESMTP" (there's a bloody-minded one that
929 says "ESMTP not spoken here"). Cope with that case.
931 September 2000: Time has passed, and it seems reasonable now to always send
932 EHLO at the start. It is also convenient to make the change while installing
935 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
936 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
937 would be no way to send out the mails, so there is now a host list
938 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
939 PIPELINING problem as well. Maybe it can also be useful to cure other
940 problems with broken servers.
942 Exim originally sent "Helo" at this point and ran for nearly a year that way.
943 Then somebody tried it with a Microsoft mailer... It seems that all other
944 mailers use upper case for some reason (the RFC is quite clear about case
945 independence) so, for peace of mind, I gave in. */
947 esmtp = verify_check_this_host(&(ob->hosts_avoid_esmtp), NULL,
948 host->name, host->address, NULL) != OK;
952 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
953 lmtp? "LHLO" : "EHLO", helo_data) < 0)
955 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
956 ob->command_timeout))
958 if (errno != 0 || buffer[0] == 0 || lmtp) goto RESPONSE_FAILED;
965 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
970 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
972 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
973 ob->command_timeout)) goto RESPONSE_FAILED;
976 /* Set IGNOREQUOTA if the response to LHLO specifies support and the
977 lmtp_ignore_quota option was set. */
979 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
980 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
981 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
983 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
986 tls_offered = esmtp &&
987 pcre_exec(regex_STARTTLS, NULL, CS buffer, Ustrlen(buffer), 0,
988 PCRE_EOPT, NULL, 0) >= 0;
992 /* For continuing deliveries down the same channel, the socket is the standard
993 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
994 below). Set up the pointer to where subsequent commands will be left, for
995 error messages. Note that smtp_use_size and smtp_use_pipelining will have been
996 set from the command line if they were set in the process that passed the
1001 inblock.sock = outblock.sock = fileno(stdin);
1002 smtp_command = big_buffer;
1005 /* If TLS is available on this connection, whether continued or not, attempt to
1006 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1007 send another EHLO - the server may give a different answer in secure mode. We
1008 use a separate buffer for reading the response to STARTTLS so that if it is
1009 negative, the original EHLO data is available for subsequent analysis, should
1010 the client not be required to use TLS. If the response is bad, copy the buffer
1011 for error analysis. */
1014 if (tls_offered && !suppress_tls &&
1015 verify_check_this_host(&(ob->hosts_avoid_tls), NULL, host->name,
1016 host->address, NULL) != OK)
1018 uschar buffer2[4096];
1019 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1022 /* If there is an I/O error, transmission of this message is deferred. If
1023 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1024 false, we also defer. However, if there is a temporary rejection of STARTTLS
1025 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1026 STARTTLS, we carry on. This means we will try to send the message in clear,
1027 unless the host is in hosts_require_tls (tested below). */
1029 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1030 ob->command_timeout))
1032 Ustrncpy(buffer, buffer2, sizeof(buffer));
1033 if (errno != 0 || buffer2[0] == 0 ||
1034 (buffer2[0] == '4' && !ob->tls_tempfail_tryclear))
1035 goto RESPONSE_FAILED;
1038 /* STARTTLS accepted: try to negotiate a TLS session. */
1042 int rc = tls_client_start(inblock.sock, host, addrlist,
1043 NULL, /* No DH param */
1044 ob->tls_certificate,
1046 ob->tls_verify_certificates,
1048 ob->tls_require_ciphers,
1049 ob->command_timeout);
1051 /* TLS negotiation failed; give an error. From outside, this function may
1052 be called again to try in clear on a new connection, if the options permit
1053 it for this host. */
1057 save_errno = ERRNO_TLSFAILURE;
1058 message = US"failure while setting up TLS session";
1063 /* TLS session is set up */
1065 for (addr = addrlist; addr != NULL; addr = addr->next)
1067 if (addr->transport_return == PENDING_DEFER)
1069 addr->cipher = tls_cipher;
1070 addr->peerdn = tls_peerdn;
1076 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. */
1078 if (tls_active >= 0)
1080 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n", lmtp? "LHLO" : "EHLO",
1083 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1084 ob->command_timeout))
1085 goto RESPONSE_FAILED;
1088 /* If the host is required to use a secure channel, ensure that we
1091 else if (verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
1092 host->address, NULL) == OK)
1094 save_errno = ERRNO_TLSREQUIRED;
1095 message = string_sprintf("a TLS session is required for %s [%s], but %s",
1096 host->name, host->address,
1097 tls_offered? "an attempt to start TLS failed" :
1098 "the server did not offer TLS support");
1103 /* If TLS is active, we have just started it up and re-done the EHLO command,
1104 so its response needs to be analyzed. If TLS is not active and this is a
1105 continued session down a previously-used socket, we haven't just done EHLO, so
1108 if (continue_hostname == NULL
1115 uschar *fail_reason = US"server did not advertise AUTH support";
1117 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
1118 lmtp_ignore_quota option was set. */
1120 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1121 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1122 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1124 /* If the response to EHLO specified support for the SIZE parameter, note
1125 this, provided size_addition is non-negative. */
1127 smtp_use_size = esmtp && ob->size_addition >= 0 &&
1128 pcre_exec(regex_SIZE, NULL, CS buffer, Ustrlen(CS buffer), 0,
1129 PCRE_EOPT, NULL, 0) >= 0;
1131 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
1132 the current host, esmtp will be false, so PIPELINING can never be used. */
1134 smtp_use_pipelining = esmtp &&
1135 pcre_exec(regex_PIPELINING, NULL, CS buffer, Ustrlen(CS buffer), 0,
1136 PCRE_EOPT, NULL, 0) >= 0;
1138 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
1139 smtp_use_pipelining? "" : "not ");
1141 /* Note if the response to EHLO specifies support for the AUTH extension.
1142 If it has, check that this host is one we want to authenticate to, and do
1143 the business. The host name and address must be available when the
1144 authenticator's client driver is running. */
1146 smtp_authenticated = FALSE;
1147 require_auth = verify_check_this_host(&(ob->hosts_require_auth), NULL,
1148 host->name, host->address, NULL);
1150 if (esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
1152 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
1153 expand_nmax = -1; /* reset */
1155 /* Must not do this check until after we have saved the result of the
1156 regex match above. */
1158 if (require_auth == OK ||
1159 verify_check_this_host(&(ob->hosts_try_auth), NULL, host->name,
1160 host->address, NULL) == OK)
1163 fail_reason = US"no common mechanisms were found";
1165 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1167 /* Scan the configured authenticators looking for one which is configured
1168 for use as a client and whose name matches an authentication mechanism
1169 supported by the server. If one is found, attempt to authenticate by
1170 calling its client function. */
1172 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1175 if (!au->client) continue;
1177 /* Loop to scan supported server mechanisms */
1182 int len = Ustrlen(au->public_name);
1183 while (isspace(*p)) p++;
1185 if (strncmpic(au->public_name, p, len) != 0 ||
1186 (p[len] != 0 && !isspace(p[len])))
1188 while (*p != 0 && !isspace(*p)) p++;
1192 /* Found data for a listed mechanism. Call its client entry. Set
1193 a flag in the outblock so that data is overwritten after sending so
1194 that reflections don't show it. */
1196 fail_reason = US"authentication attempt(s) failed";
1197 outblock.authenticating = TRUE;
1198 rc = (au->info->clientcode)(au, &inblock, &outblock,
1199 ob->command_timeout, buffer, sizeof(buffer));
1200 outblock.authenticating = FALSE;
1201 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1204 /* A temporary authentication failure must hold up delivery to
1205 this host. After a permanent authentication failure, we carry on
1206 to try other authentication methods. If all fail hard, try to
1207 deliver the message unauthenticated unless require_auth was set. */
1212 smtp_authenticated = TRUE; /* stops the outer loop */
1215 /* Failure after writing a command */
1220 /* Failure after reading a response */
1223 if (errno != 0 || buffer[0] != '5') goto RESPONSE_FAILED;
1224 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1225 au->name, host->name, host->address, buffer);
1228 /* Failure by some other means. In effect, the authenticator
1229 decided it wasn't prepared to handle this case. Typically this
1230 is the result of "fail" in an expansion string. Do we need to
1231 log anything here? Feb 2006: a message is now put in the buffer
1232 if logging is required. */
1236 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1237 "authentication H=%s [%s] %s", au->name, host->name,
1238 host->address, buffer);
1241 /* Internal problem, message in buffer. */
1245 set_errno(addrlist, 0, string_copy(buffer), DEFER, FALSE);
1249 break; /* If not authenticated, try next authenticator */
1250 } /* Loop for scanning supported server mechanisms */
1251 } /* Loop for further authenticators */
1255 /* If we haven't authenticated, but are required to, give up. */
1257 if (require_auth == OK && !smtp_authenticated)
1260 set_errno(addrlist, ERRNO_AUTHFAIL,
1261 string_sprintf("authentication required but %s", fail_reason), DEFER,
1267 /* The setting up of the SMTP call is now complete. Any subsequent errors are
1268 message-specific. */
1272 /* If there is a filter command specified for this transport, we can now
1273 set it up. This cannot be done until the identify of the host is known. */
1275 if (tblock->filter_command != NULL)
1279 sprintf(CS buffer, "%.50s transport", tblock->name);
1280 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
1281 TRUE, DEFER, addrlist, buffer, NULL);
1283 /* On failure, copy the error to all addresses, abandon the SMTP call, and
1288 set_errno(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
1296 /* For messages that have more than the maximum number of envelope recipients,
1297 we want to send several transactions down the same SMTP connection. (See
1298 comments in deliver.c as to how this reconciles, heuristically, with
1299 remote_max_parallel.) This optimization was added to Exim after the following
1300 code was already working. The simplest way to put it in without disturbing the
1301 code was to use a goto to jump back to this point when there is another
1302 transaction to handle. */
1305 sync_addr = first_addr;
1309 completed_address = FALSE;
1312 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
1313 qualification, send it, adding something to the message size to allow for
1314 imprecision and things that get added en route. Exim keeps the number of lines
1315 in a message, so we can give an accurate value for the original message, but we
1316 need some additional to handle added headers. (Double "." characters don't get
1317 included in the count.) */
1324 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
1328 /* Add the authenticated sender address if present */
1330 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1331 local_authenticated_sender != NULL)
1333 string_format(p, sizeof(buffer) - (p-buffer), " AUTH=%s",
1334 auth_xtextencode(local_authenticated_sender,
1335 Ustrlen(local_authenticated_sender)));
1338 /* From here until we send the DATA command, we can make use of PIPELINING
1339 if the server host supports it. The code has to be able to check the responses
1340 at any point, for when the buffer fills up, so we write it totally generally.
1341 When PIPELINING is off, each command written reports that it has flushed the
1344 pending_MAIL = TRUE; /* The block starts with MAIL */
1346 rc = smtp_write_command(&outblock, smtp_use_pipelining,
1347 "MAIL FROM:<%s>%s\r\n", return_path, buffer);
1348 mail_command = string_copy(big_buffer); /* Save for later error message */
1352 case -1: /* Transmission error */
1355 case +1: /* Block was sent */
1356 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1357 ob->command_timeout))
1359 if (errno == 0 && buffer[0] == '4')
1361 errno = ERRNO_MAIL4XX;
1362 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1364 goto RESPONSE_FAILED;
1366 pending_MAIL = FALSE;
1370 /* Pass over all the relevant recipient addresses for this host, which are the
1371 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
1372 several before we have to read the responses for those seen so far. This
1373 checking is done by a subroutine because it also needs to be done at the end.
1374 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
1375 the next one if not all are sent.
1377 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
1378 last address because we want to abort if any recipients have any kind of
1379 problem, temporary or permanent. We know that all recipient addresses will have
1380 the PENDING_DEFER status, because only one attempt is ever made, and we know
1381 that max_rcpt will be large, so all addresses will be done at once. */
1383 for (addr = first_addr;
1384 address_count < max_rcpt && addr != NULL;
1390 if (addr->transport_return != PENDING_DEFER) continue;
1393 no_flush = smtp_use_pipelining && (!mua_wrapper || addr->next != NULL);
1395 /* Now send the RCPT command, and process outstanding responses when
1396 necessary. After a timeout on RCPT, we just end the function, leaving the
1397 yield as OK, because this error can often mean that there is a problem with
1398 just one address, so we don't want to delay the host. */
1400 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s\r\n",
1401 transport_rcpt_address(addr, tblock->rcpt_include_affixes), igquotstr);
1402 if (count < 0) goto SEND_FAILED;
1405 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
1406 &sync_addr, host, count, pending_MAIL, 0, &inblock,
1407 ob->command_timeout, buffer, sizeof(buffer)))
1409 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1410 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1413 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1414 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1415 case 0: /* No 2xx or 5xx, but no probs */
1418 case -1: goto END_OFF; /* Timeout on RCPT */
1419 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
1421 pending_MAIL = FALSE; /* Dealt with MAIL */
1423 } /* Loop for next address */
1425 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
1426 permanently or temporarily. We should have flushed and synced after the last
1431 address_item *badaddr;
1432 for (badaddr = first_addr; badaddr != NULL; badaddr = badaddr->next)
1434 if (badaddr->transport_return != PENDING_OK) break;
1436 if (badaddr != NULL)
1438 set_errno(addrlist, 0, badaddr->message, FAIL,
1439 testflag(badaddr, af_pass_message));
1444 /* If ok is TRUE, we know we have got at least one good recipient, and must now
1445 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
1446 have a good recipient buffered up if we are pipelining. We don't want to waste
1447 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
1448 are pipelining. The responses are all handled by sync_responses(). */
1450 if (ok || (smtp_use_pipelining && !mua_wrapper))
1452 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
1453 if (count < 0) goto SEND_FAILED;
1454 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
1455 host, count, pending_MAIL, ok? +1 : -1, &inblock,
1456 ob->command_timeout, buffer, sizeof(buffer)))
1458 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1459 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1462 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1463 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1464 case 0: break; /* No 2xx or 5xx, but no probs */
1466 case -1: goto END_OFF; /* Timeout on RCPT */
1467 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
1471 /* Save the first address of the next batch. */
1475 /* If there were no good recipients (but otherwise there have been no
1476 problems), just set ok TRUE, since we have handled address-specific errors
1477 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
1478 for handling the SMTP dot-handling protocol, flagging to apply to headers as
1479 well as body. Set the appropriate timeout value to be used for each chunk.
1480 (Haven't been able to make it work using select() for writing yet.) */
1482 if (!ok) ok = TRUE; else
1484 sigalrm_seen = FALSE;
1485 transport_write_timeout = ob->data_timeout;
1486 smtp_command = US"sending data block"; /* For error messages */
1487 DEBUG(D_transport|D_v)
1488 debug_printf(" SMTP>> writing message and terminating \".\"\n");
1489 transport_count = 0;
1490 #ifdef EXPERIMENTAL_DOMAINKEYS
1491 if ( (ob->dk_private_key != NULL) && (ob->dk_selector != NULL) )
1492 ok = dk_transport_write_message(addrlist, inblock.sock,
1493 topt_use_crlf | topt_end_dot | topt_escape_headers |
1494 (tblock->body_only? topt_no_headers : 0) |
1495 (tblock->headers_only? topt_no_body : 0) |
1496 (tblock->return_path_add? topt_add_return_path : 0) |
1497 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1498 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1499 0, /* No size limit */
1500 tblock->add_headers, tblock->remove_headers,
1501 US".", US"..", /* Escaping strings */
1502 tblock->rewrite_rules, tblock->rewrite_existflags,
1503 ob->dk_private_key, ob->dk_domain, ob->dk_selector,
1504 ob->dk_canon, ob->dk_headers, ob->dk_strict);
1507 ok = transport_write_message(addrlist, inblock.sock,
1508 topt_use_crlf | topt_end_dot | topt_escape_headers |
1509 (tblock->body_only? topt_no_headers : 0) |
1510 (tblock->headers_only? topt_no_body : 0) |
1511 (tblock->return_path_add? topt_add_return_path : 0) |
1512 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1513 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1514 0, /* No size limit */
1515 tblock->add_headers, tblock->remove_headers,
1516 US".", US"..", /* Escaping strings */
1517 tblock->rewrite_rules, tblock->rewrite_existflags);
1519 /* transport_write_message() uses write() because it is called from other
1520 places to write to non-sockets. This means that under some OS (e.g. Solaris)
1521 it can exit with "Broken pipe" as its error. This really means that the
1522 socket got closed at the far end. */
1524 transport_write_timeout = 0; /* for subsequent transports */
1526 /* Failure can either be some kind of I/O disaster (including timeout),
1527 or the failure of a transport filter or the expansion of added headers. */
1531 buffer[0] = 0; /* There hasn't been a response */
1532 goto RESPONSE_FAILED;
1535 /* We used to send the terminating "." explicitly here, but because of
1536 buffering effects at both ends of TCP/IP connections, you don't gain
1537 anything by keeping it separate, so it might as well go in the final
1538 data buffer for efficiency. This is now done by setting the topt_end_dot
1541 smtp_command = US"end of data";
1543 /* For SMTP, we now read a single response that applies to the whole message.
1544 If it is OK, then all the addresses have been delivered. */
1548 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1550 if (!ok && errno == 0 && buffer[0] == '4')
1552 errno = ERRNO_DATA4XX;
1553 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1557 /* For LMTP, we get back a response for every RCPT command that we sent;
1558 some may be accepted and some rejected. For those that get a response, their
1559 status is fixed; any that are accepted have been handed over, even if later
1560 responses crash - at least, that's how I read RFC 2033.
1562 If all went well, mark the recipient addresses as completed, record which
1563 host/IPaddress they were delivered to, and cut out RSET when sending another
1564 message down the same channel. Write the completed addresses to the journal
1565 now so that they are recorded in case there is a crash of hardware or
1566 software before the spool gets updated. Also record the final SMTP
1567 confirmation if needed (for SMTP only). */
1572 int delivery_time = (int)(time(NULL) - start_delivery_time);
1575 uschar *conf = NULL;
1578 /* Make a copy of the host if it is local to this invocation
1579 of the transport. */
1583 thost = store_get(sizeof(host_item));
1585 thost->name = string_copy(host->name);
1586 thost->address = string_copy(host->address);
1590 /* Set up confirmation if needed - applies only to SMTP */
1592 if ((log_extra_selector & LX_smtp_confirmation) != 0 && !lmtp)
1594 uschar *s = string_printing(buffer);
1595 conf = (s == buffer)? (uschar *)string_copy(s) : s;
1598 /* Process all transported addresses - for LMTP, read a status for
1601 for (addr = addrlist; addr != first_addr; addr = addr->next)
1603 if (addr->transport_return != PENDING_OK) continue;
1605 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
1606 remaining addresses. Otherwise, it's a return code for just the one
1607 address. For temporary errors, add a retry item for the address so that
1608 it doesn't get tried again too soon. */
1612 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1615 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
1616 addr->message = string_sprintf("LMTP error after %s: %s",
1617 big_buffer, string_printing(buffer));
1618 setflag(addr, af_pass_message); /* Allow message to go to user */
1619 if (buffer[0] == '5')
1620 addr->transport_return = FAIL;
1623 errno = ERRNO_DATA4XX;
1624 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1625 addr->transport_return = DEFER;
1626 retry_add_item(addr, addr->address_retry_key, 0);
1630 completed_address = TRUE; /* NOW we can set this flag */
1633 /* SMTP, or success return from LMTP for this address. Pass back the
1634 actual host that was used. */
1636 addr->transport_return = OK;
1637 addr->more_errno = delivery_time;
1638 addr->host_used = thost;
1639 addr->special_action = flag;
1640 addr->message = conf;
1643 /* Update the journal. For homonymic addresses, use the base address plus
1644 the transport name. See lots of comments in deliver.c about the reasons
1645 for the complications when homonyms are involved. Just carry on after
1646 write error, as it may prove possible to update the spool file later. */
1648 if (testflag(addr, af_homonym))
1649 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
1651 sprintf(CS buffer, "%.500s\n", addr->unique);
1653 DEBUG(D_deliver) debug_printf("journalling %s", buffer);
1654 len = Ustrlen(CS buffer);
1655 if (write(journal_fd, buffer, len) != len)
1656 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
1657 "%s: %s", buffer, strerror(errno));
1660 /* Ensure the journal file is pushed out to disk. */
1662 if (fsync(journal_fd) < 0)
1663 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
1669 /* Handle general (not specific to one address) failures here. The value of ok
1670 is used to skip over this code on the falling through case. A timeout causes a
1671 deferral. Other errors may defer or fail according to the response code, and
1672 may set up a special errno value, e.g. after connection chopped, which is
1673 assumed if errno == 0 and there is no text in the buffer. If control reaches
1674 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
1675 the problem is not related to this specific message. */
1684 send_quit = check_response(host, &save_errno, addrlist->more_errno,
1685 buffer, &code, &message, &pass_message);
1691 message = US string_sprintf("send() to %s [%s] failed: %s",
1692 host->name, host->address, strerror(save_errno));
1696 /* This label is jumped to directly when a TLS negotiation has failed,
1697 or was not done for a host for which it is required. Values will be set
1698 in message and save_errno, and setting_up will always be true. Treat as
1699 a temporary error. */
1706 /* If the failure happened while setting up the call, see if the failure was
1707 a 5xx response (this will either be on connection, or following HELO - a 5xx
1708 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
1709 never going to accept them. For other errors during setting up (timeouts or
1710 whatever), defer all addresses, and yield DEFER, so that the host is not
1711 tried again for a while. */
1714 ok = FALSE; /* For when reached by GOTO */
1720 set_errno(addrlist, save_errno, message, FAIL, pass_message);
1724 set_errno(addrlist, save_errno, message, DEFER, pass_message);
1729 /* We want to handle timeouts after MAIL or "." and loss of connection after
1730 "." specially. They can indicate a problem with the sender address or with
1731 the contents of the message rather than a real error on the connection. These
1732 cases are treated in the same way as a 4xx response. This next bit of code
1733 does the classification. */
1744 message_error = TRUE;
1748 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
1749 Ustrncmp(smtp_command,"end ",4) == 0;
1752 case ERRNO_SMTPCLOSED:
1753 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
1757 message_error = FALSE;
1761 /* Handle the cases that are treated as message errors. These are:
1763 (a) negative response or timeout after MAIL
1764 (b) negative response after DATA
1765 (c) negative response or timeout or dropped connection after "."
1767 It won't be a negative response or timeout after RCPT, as that is dealt
1768 with separately above. The action in all cases is to set an appropriate
1769 error code for all the addresses, but to leave yield set to OK because the
1770 host itself has not failed. Of course, it might in practice have failed
1771 when we've had a timeout, but if so, we'll discover that at the next
1772 delivery attempt. For a temporary error, set the message_defer flag, and
1773 write to the logs for information if this is not the last host. The error
1774 for the last host will be logged as part of the address's log line. */
1778 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
1779 set_errno(addrlist, save_errno, message, (code == '5')? FAIL : DEFER,
1782 /* If there's an errno, the message contains just the identity of
1785 if (code != '5') /* Anything other than 5 is treated as temporary */
1788 message = US string_sprintf("%s: %s", message, strerror(save_errno));
1789 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
1790 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
1791 *message_defer = TRUE;
1795 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
1796 ".", or some other transportation error. We defer all addresses and yield
1797 DEFER, except for the case of failed add_headers expansion, or a transport
1798 filter failure, when the yield should be ERROR, to stop it trying other
1803 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
1804 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
1805 set_errno(addrlist, save_errno, message, DEFER, pass_message);
1811 /* If all has gone well, send_quit will be set TRUE, implying we can end the
1812 SMTP session tidily. However, if there were too many addresses to send in one
1813 message (indicated by first_addr being non-NULL) we want to carry on with the
1814 rest of them. Also, it is desirable to send more than one message down the SMTP
1815 connection if there are several waiting, provided we haven't already sent so
1816 many as to hit the configured limit. The function transport_check_waiting looks
1817 for a waiting message and returns its id. Then transport_pass_socket tries to
1818 set up a continued delivery by passing the socket on to another process. The
1819 variable send_rset is FALSE if a message has just been successfully transfered.
1821 If we are already sending down a continued channel, there may be further
1822 addresses not yet delivered that are aimed at the same host, but which have not
1823 been passed in this run of the transport. In this case, continue_more will be
1824 true, and all we should do is send RSET if necessary, and return, leaving the
1827 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
1828 do not want to continue with other messages down the same channel, because that
1829 can lead to looping between two or more messages, all with the same,
1830 temporarily failing address(es). [The retry information isn't updated yet, so
1831 new processes keep on trying.] We probably also don't want to try more of this
1832 message's addresses either.
1834 If we have started a TLS session, we have to end it before passing the
1835 connection to a new process. However, not all servers can handle this (Exim
1836 can), so we do not pass such a connection on if the host matches
1837 hosts_nopass_tls. */
1840 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
1841 "yield=%d first_address is %sNULL\n", ok, send_quit, send_rset,
1842 continue_more, yield, (first_addr == NULL)? "":"not ");
1844 if (completed_address && ok && send_quit)
1847 if (first_addr != NULL || continue_more ||
1850 verify_check_this_host(&(ob->hosts_nopass_tls), NULL, host->name,
1851 host->address, NULL) != OK)
1853 transport_check_waiting(tblock->name, host->name,
1854 tblock->connection_max_messages, new_message_id, &more)
1862 if (! (ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
1864 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
1865 host->address, strerror(save_errno));
1868 else if (! (ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1869 ob->command_timeout)))
1872 send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
1876 DEBUG(D_transport) debug_printf("%s\n", msg);
1881 /* Either RSET was not needed, or it succeeded */
1885 if (first_addr != NULL) /* More addresses still to be sent */
1886 { /* in this run of the transport */
1887 continue_sequence++; /* Causes * in logging */
1890 if (continue_more) return yield; /* More addresses for another run */
1892 /* Pass the socket to a new Exim process. Before doing so, we must shut
1893 down TLS. Not all MTAs allow for the continuation of the SMTP session
1894 when TLS is shut down. We test for this by sending a new EHLO. If we
1895 don't get a good response, we don't attempt to pass the socket on. */
1898 if (tls_active >= 0)
1901 ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
1902 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1903 ob->command_timeout);
1907 /* If the socket is successfully passed, we musn't send QUIT (or
1908 indeed anything!) from here. */
1910 if (ok && transport_pass_socket(tblock->name, host->name, host->address,
1911 new_message_id, inblock.sock))
1917 /* If RSET failed and there are addresses left, they get deferred. */
1919 else set_errno(first_addr, errno, msg, DEFER, FALSE);
1923 /* End off tidily with QUIT unless the connection has died or the socket has
1924 been passed to another process. There has been discussion on the net about what
1925 to do after sending QUIT. The wording of the RFC suggests that it is necessary
1926 to wait for a response, but on the other hand, there isn't anything one can do
1927 with an error response, other than log it. Exim used to do that. However,
1928 further discussion suggested that it is positively advantageous not to wait for
1929 the response, but to close the session immediately. This is supposed to move
1930 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
1931 load from the server. (Hosts that are both servers and clients may not see much
1932 difference, of course.) Further discussion indicated that this was safe to do
1933 on Unix systems which have decent implementations of TCP/IP that leave the
1934 connection around for a while (TIME_WAIT) after the application has gone away.
1935 This enables the response sent by the server to be properly ACKed rather than
1936 timed out, as can happen on broken TCP/IP implementations on other OS.
1938 This change is being made on 31-Jul-98. After over a year of trouble-free
1939 operation, the old commented-out code was removed on 17-Sep-99. */
1942 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
1950 /* Close the socket, and return the appropriate value, first setting
1951 continue_transport and continue_hostname NULL to prevent any other addresses
1952 that may include the host from trying to re-use a continuation socket. This
1953 works because the NULL setting is passed back to the calling process, and
1954 remote_max_parallel is forced to 1 when delivering over an existing connection,
1956 If all went well and continue_more is set, we shouldn't actually get here if
1957 there are further addresses, as the return above will be taken. However,
1958 writing RSET might have failed, or there may be other addresses whose hosts are
1959 specified in the transports, and therefore not visible at top level, in which
1960 case continue_more won't get set. */
1962 (void)close(inblock.sock);
1963 continue_transport = NULL;
1964 continue_hostname = NULL;
1971 /*************************************************
1972 * Closedown entry point *
1973 *************************************************/
1975 /* This function is called when exim is passed an open smtp channel
1976 from another incarnation, but the message which it has been asked
1977 to deliver no longer exists. The channel is on stdin.
1979 We might do fancy things like looking for another message to send down
1980 the channel, but if the one we sought has gone, it has probably been
1981 delivered by some other process that itself will seek further messages,
1982 so just close down our connection.
1984 Argument: pointer to the transport instance block
1989 smtp_transport_closedown(transport_instance *tblock)
1991 smtp_transport_options_block *ob =
1992 (smtp_transport_options_block *)(tblock->options_block);
1993 smtp_inblock inblock;
1994 smtp_outblock outblock;
1996 uschar inbuffer[4096];
1997 uschar outbuffer[16];
1999 inblock.sock = fileno(stdin);
2000 inblock.buffer = inbuffer;
2001 inblock.buffersize = sizeof(inbuffer);
2002 inblock.ptr = inbuffer;
2003 inblock.ptrend = inbuffer;
2005 outblock.sock = inblock.sock;
2006 outblock.buffersize = sizeof(outbuffer);
2007 outblock.buffer = outbuffer;
2008 outblock.ptr = outbuffer;
2009 outblock.cmd_count = 0;
2010 outblock.authenticating = FALSE;
2012 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2013 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2014 ob->command_timeout);
2015 (void)close(inblock.sock);
2020 /*************************************************
2021 * Prepare addresses for delivery *
2022 *************************************************/
2024 /* This function is called to flush out error settings from previous delivery
2025 attempts to other hosts. It also records whether we got here via an MX record
2026 or not in the more_errno field of the address. We are interested only in
2027 addresses that are still marked DEFER - others may have got delivered to a
2028 previously considered IP address. Set their status to PENDING_DEFER to indicate
2029 which ones are relevant this time.
2032 addrlist the list of addresses
2033 host the host we are delivering to
2035 Returns: the first address for this delivery
2038 static address_item *
2039 prepare_addresses(address_item *addrlist, host_item *host)
2041 address_item *first_addr = NULL;
2043 for (addr = addrlist; addr != NULL; addr = addr->next)
2045 if (addr->transport_return != DEFER) continue;
2046 if (first_addr == NULL) first_addr = addr;
2047 addr->transport_return = PENDING_DEFER;
2048 addr->basic_errno = 0;
2049 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
2050 addr->message = NULL;
2052 addr->cipher = NULL;
2053 addr->peerdn = NULL;
2061 /*************************************************
2062 * Main entry point *
2063 *************************************************/
2065 /* See local README for interface details. As this is a remote transport, it is
2066 given a chain of addresses to be delivered in one connection, if possible. It
2067 always returns TRUE, indicating that each address has its own independent
2068 status set, except if there is a setting up problem, in which case it returns
2072 smtp_transport_entry(
2073 transport_instance *tblock, /* data for this instantiation */
2074 address_item *addrlist) /* addresses we are working on */
2078 int hosts_defer = 0;
2080 int hosts_looked_up = 0;
2081 int hosts_retry = 0;
2082 int hosts_serial = 0;
2083 int hosts_total = 0;
2084 int total_hosts_tried = 0;
2086 BOOL expired = TRUE;
2087 BOOL continuing = continue_hostname != NULL;
2088 uschar *expanded_hosts = NULL;
2090 uschar *tid = string_sprintf("%s transport", tblock->name);
2091 smtp_transport_options_block *ob =
2092 (smtp_transport_options_block *)(tblock->options_block);
2093 host_item *hostlist = addrlist->host_list;
2094 host_item *host = NULL;
2098 debug_printf("%s transport entered\n", tblock->name);
2099 for (addr = addrlist; addr != NULL; addr = addr->next)
2100 debug_printf(" %s\n", addr->address);
2101 if (continuing) debug_printf("already connected to %s [%s]\n",
2102 continue_hostname, continue_host_address);
2105 /* If a host list is not defined for the addresses - they must all have the
2106 same one in order to be passed to a single transport - or if the transport has
2107 a host list with hosts_override set, use the host list supplied with the
2108 transport. It is an error for this not to exist. */
2110 if (hostlist == NULL || (ob->hosts_override && ob->hosts != NULL))
2112 if (ob->hosts == NULL)
2114 addrlist->message = string_sprintf("%s transport called with no hosts set",
2116 addrlist->transport_return = PANIC;
2117 return FALSE; /* Only top address has status */
2120 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
2123 /* If the transport's host list contains no '$' characters, and we are not
2124 randomizing, it is fixed and therefore a chain of hosts can be built once
2125 and for all, and remembered for subsequent use by other calls to this
2126 transport. If, on the other hand, the host list does contain '$', or we are
2127 randomizing its order, we have to rebuild it each time. In the fixed case,
2128 as the hosts string will never be used again, it doesn't matter that we
2129 replace all the : characters with zeros. */
2131 if (ob->hostlist == NULL)
2133 uschar *s = ob->hosts;
2135 if (Ustrchr(s, '$') != NULL)
2137 expanded_hosts = expand_string(s);
2138 if (expanded_hosts == NULL)
2140 addrlist->message = string_sprintf("failed to expand list of hosts "
2141 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
2142 addrlist->transport_return = search_find_defer? DEFER : PANIC;
2143 return FALSE; /* Only top address has status */
2145 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
2146 "\"%s\"\n", s, expanded_hosts);
2150 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
2152 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
2154 /* If there was no expansion of hosts, save the host list for
2157 if (expanded_hosts == NULL) ob->hostlist = hostlist;
2160 /* This is not the first time this transport has been run in this delivery;
2161 the host list was built previously. */
2163 else hostlist = ob->hostlist;
2166 /* The host list was supplied with the address. If hosts_randomize is set, we
2167 must sort it into a random order if it did not come from MX records and has not
2168 already been randomized (but don't bother if continuing down an existing
2171 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continuing)
2173 host_item *newlist = NULL;
2174 while (hostlist != NULL)
2176 host_item *h = hostlist;
2177 hostlist = hostlist->next;
2179 h->sort_key = random_number(100);
2181 if (newlist == NULL)
2186 else if (h->sort_key < newlist->sort_key)
2193 host_item *hh = newlist;
2194 while (hh->next != NULL)
2196 if (h->sort_key < hh->next->sort_key) break;
2204 hostlist = addrlist->host_list = newlist;
2208 /* Sort out the default port. */
2210 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
2213 /* For each host-plus-IP-address on the list:
2215 . If this is a continued delivery and the host isn't the one with the
2216 current connection, skip.
2218 . If the status is unusable (i.e. previously failed or retry checked), skip.
2220 . If no IP address set, get the address, either by turning the name into
2221 an address, calling gethostbyname if gethostbyname is on, or by calling
2222 the DNS. The DNS may yield multiple addresses, in which case insert the
2223 extra ones into the list.
2225 . Get the retry data if not previously obtained for this address and set the
2226 field which remembers the state of this address. Skip if the retry time is
2227 not reached. If not, remember whether retry data was found. The retry string
2228 contains both the name and the IP address.
2230 . Scan the list of addresses and mark those whose status is DEFER as
2231 PENDING_DEFER. These are the only ones that will be processed in this cycle
2234 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
2235 Some addresses may be successfully delivered, others may fail, and yet
2236 others may get temporary errors and so get marked DEFER.
2238 . The return from the delivery attempt is OK if a connection was made and a
2239 valid SMTP dialogue was completed. Otherwise it is DEFER.
2241 . If OK, add a "remove" retry item for this host/IPaddress, if any.
2243 . If fail to connect, or other defer state, add a retry item.
2245 . If there are any addresses whose status is still DEFER, carry on to the
2246 next host/IPaddress, unless we have tried the number of hosts given
2247 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
2248 there is some fancy logic for hosts_max_try that means its limit can be
2249 overstepped in some circumstances.
2251 If we get to the end of the list, all hosts have deferred at least one address,
2252 or not reached their retry times. If delay_after_cutoff is unset, it requests a
2253 delivery attempt to those hosts whose last try was before the arrival time of
2254 the current message. To cope with this, we have to go round the loop a second
2255 time. After that, set the status and error data for any addresses that haven't
2256 had it set already. */
2258 for (cutoff_retry = 0; expired &&
2259 cutoff_retry < ((ob->delay_after_cutoff)? 1 : 2);
2262 host_item *nexthost = NULL;
2263 int unexpired_hosts_tried = 0;
2265 for (host = hostlist;
2267 unexpired_hosts_tried < ob->hosts_max_try &&
2268 total_hosts_tried < ob->hosts_max_try_hardlimit;
2274 BOOL serialized = FALSE;
2275 BOOL host_is_expired = FALSE;
2276 BOOL message_defer = FALSE;
2277 BOOL ifchanges = FALSE;
2278 BOOL some_deferred = FALSE;
2279 address_item *first_addr = NULL;
2280 uschar *interface = NULL;
2281 uschar *retry_host_key = NULL;
2282 uschar *retry_message_key = NULL;
2283 uschar *serialize_key = NULL;
2285 /* Default next host is next host. :-) But this can vary if the
2286 hosts_max_try limit is hit (see below). It may also be reset if a host
2287 address is looked up here (in case the host was multihomed). */
2289 nexthost = host->next;
2291 /* Set the flag requesting that this host be added to the waiting
2292 database if the delivery fails temporarily or if we are running with
2293 queue_smtp or a 2-stage queue run. This gets unset for certain
2294 kinds of error, typically those that are specific to the message. */
2296 host->update_waiting = TRUE;
2298 /* If the address hasn't yet been obtained from the host name, look it up
2299 now, unless the host is already marked as unusable. If it is marked as
2300 unusable, it means that the router was unable to find its IP address (in
2301 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
2302 the lookup failed last time. We don't get this far if *all* MX records
2303 point to non-existent hosts; that is treated as a hard error.
2305 We can just skip this host entirely. When the hosts came from the router,
2306 the address will timeout based on the other host(s); when the address is
2307 looked up below, there is an explicit retry record added.
2309 Note that we mustn't skip unusable hosts if the address is not unset; they
2310 may be needed as expired hosts on the 2nd time round the cutoff loop. */
2312 if (host->address == NULL)
2314 int new_port, flags;
2316 uschar *canonical_name;
2318 if (host->status >= hstatus_unusable)
2320 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
2325 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
2327 /* The host name is permitted to have an attached port. Find it, and
2328 strip it from the name. Just remember it for now. */
2330 new_port = host_item_get_port(host);
2332 /* Count hosts looked up */
2336 /* Find by name if so configured, or if it's an IP address. We don't
2337 just copy the IP address, because we need the test-for-local to happen. */
2339 flags = HOST_FIND_BY_A;
2340 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
2341 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
2343 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
2344 rc = host_find_byname(host, NULL, flags, &canonical_name, TRUE);
2346 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
2347 &canonical_name, NULL);
2349 /* Update the host (and any additional blocks, resulting from
2350 multihoming) with a host-specific port, if any. */
2352 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
2354 /* Failure to find the host at this time (usually DNS temporary failure)
2355 is really a kind of routing failure rather than a transport failure.
2356 Therefore we add a retry item of the routing kind, not to stop us trying
2357 to look this name up here again, but to ensure the address gets timed
2358 out if the failures go on long enough. A complete failure at this point
2359 commonly points to a configuration error, but the best action is still
2360 to carry on for the next host. */
2362 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
2364 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
2366 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
2367 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
2368 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
2369 host->status = hstatus_unusable;
2371 for (addr = addrlist; addr != NULL; addr = addr->next)
2373 if (addr->transport_return != DEFER) continue;
2374 addr->basic_errno = ERRNO_UNKNOWNHOST;
2376 string_sprintf("failed to lookup IP address for %s", host->name);
2381 /* If the host is actually the local host, we may have a problem, or
2382 there may be some cunning configuration going on. In the problem case,
2383 log things and give up. The default transport status is already DEFER. */
2385 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
2387 for (addr = addrlist; addr != NULL; addr = addr->next)
2389 addr->basic_errno = 0;
2390 addr->message = string_sprintf("%s transport found host %s to be "
2391 "local", tblock->name, host->name);
2395 } /* End of block for IP address lookup */
2397 /* If this is a continued delivery, we are interested only in the host
2398 which matches the name of the existing open channel. The check is put
2399 here after the local host lookup, in case the name gets expanded as a
2400 result of the lookup. Set expired FALSE, to save the outer loop executing
2403 if (continuing && (Ustrcmp(continue_hostname, host->name) != 0 ||
2404 Ustrcmp(continue_host_address, host->address) != 0))
2407 continue; /* With next host */
2410 /* Reset the default next host in case a multihomed host whose addresses
2411 are not looked up till just above added to the host list. */
2413 nexthost = host->next;
2415 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
2416 domain is in queue_smtp_domains, we don't actually want to attempt any
2417 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
2418 there is a lookup defer in queue_smtp_domains, proceed as if the domain
2419 were not in it. We don't want to hold up all SMTP deliveries! Except when
2420 doing a two-stage queue run, don't do this if forcing. */
2422 if ((!deliver_force || queue_2stage) && (queue_smtp ||
2423 match_isinlist(addrlist->domain, &queue_smtp_domains, 0,
2424 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
2427 for (addr = addrlist; addr != NULL; addr = addr->next)
2429 if (addr->transport_return != DEFER) continue;
2430 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
2432 continue; /* With next host */
2435 /* Count hosts being considered - purely for an intelligent comment
2436 if none are usable. */
2440 /* Set $host and $host address now in case they are needed for the
2441 interface expansion or the serialize_hosts check; they remain set if an
2442 actual delivery happens. */
2444 deliver_host = host->name;
2445 deliver_host_address = host->address;
2447 /* Set up a string for adding to the retry key if the port number is not
2448 the standard SMTP port. A host may have its own port setting that overrides
2451 pistring = string_sprintf(":%d", (host->port == PORT_NONE)?
2453 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
2455 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
2456 string changes upon expansion, we must add it to the key that is used for
2457 retries, because connections to the same host from a different interface
2458 should be treated separately. */
2460 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET : AF_INET6;
2461 if (!smtp_get_interface(ob->interface, host_af, addrlist, &ifchanges,
2464 if (ifchanges) pistring = string_sprintf("%s/%s", pistring, interface);
2466 /* The first time round the outer loop, check the status of the host by
2467 inspecting the retry data. The second time round, we are interested only
2468 in expired hosts that haven't been tried since this message arrived. */
2470 if (cutoff_retry == 0)
2472 /* Ensure the status of the address is set by checking retry data if
2473 necessary. There maybe host-specific retry data (applicable to all
2474 messages) and also data for retries of a specific message at this host.
2475 If either of these retry records are actually read, the keys used are
2476 returned to save recomputing them later. */
2478 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
2479 ob->retry_include_ip_address, &retry_host_key, &retry_message_key);
2481 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
2482 (host->address == NULL)? US"" : host->address, pistring,
2483 (host->status == hstatus_usable)? "usable" :
2484 (host->status == hstatus_unusable)? "unusable" :
2485 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
2487 /* Skip this address if not usable at this time, noting if it wasn't
2488 actually expired, both locally and in the address. */
2490 switch (host->status)
2492 case hstatus_unusable:
2494 setflag(addrlist, af_retry_skipped);
2497 case hstatus_unusable_expired:
2500 case hwhy_retry: hosts_retry++; break;
2501 case hwhy_failed: hosts_fail++; break;
2502 case hwhy_deferred: hosts_defer++; break;
2505 /* If there was a retry message key, implying that previously there
2506 was a message-specific defer, we don't want to update the list of
2507 messages waiting for this host. */
2509 if (retry_message_key != NULL) host->update_waiting = FALSE;
2510 continue; /* With the next host or IP address */
2514 /* Second time round the loop: if the address is set but expired, and
2515 the message is newer than the last try, let it through. */
2519 if (host->address == NULL ||
2520 host->status != hstatus_unusable_expired ||
2521 host->last_try > received_time)
2524 debug_printf("trying expired host %s [%s]%s\n",
2525 host->name, host->address, pistring);
2526 host_is_expired = TRUE;
2529 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
2530 it remains TRUE only if all hosts are expired and none are actually tried.
2535 /* If this host is listed as one to which access must be serialized,
2536 see if another Exim process has a connection to it, and if so, skip
2537 this host. If not, update the database to record our connection to it
2538 and remember this for later deletion. Do not do any of this if we are
2539 sending the message down a pre-existing connection. */
2542 verify_check_this_host(&(ob->serialize_hosts), NULL, host->name,
2543 host->address, NULL) == OK)
2545 serialize_key = string_sprintf("host-serialize-%s", host->name);
2546 if (!enq_start(serialize_key))
2549 debug_printf("skipping host %s because another Exim process "
2550 "is connected to it\n", host->name);
2557 /* OK, we have an IP address that is not waiting for its retry time to
2558 arrive (it might be expired) OR (second time round the loop) we have an
2559 expired host that hasn't been tried since the message arrived. Have a go
2560 at delivering the message to it. First prepare the addresses by flushing
2561 out the result of previous attempts, and finding the first address that
2562 is still to be delivered. */
2564 first_addr = prepare_addresses(addrlist, host);
2566 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
2567 message_id, host->name, host->address, addrlist->address,
2568 (addrlist->next == NULL)? "" : ", ...");
2570 set_process_info("delivering %s to %s [%s] (%s%s)",
2571 message_id, host->name, host->address, addrlist->address,
2572 (addrlist->next == NULL)? "" : ", ...");
2574 /* This is not for real; don't do the delivery. If there are
2575 any remaining hosts, list them. */
2580 set_errno(addrlist, 0, NULL, OK, FALSE);
2581 for (addr = addrlist; addr != NULL; addr = addr->next)
2583 addr->host_used = host;
2584 addr->special_action = '*';
2585 addr->message = US"delivery bypassed by -N option";
2589 debug_printf("*** delivery by %s transport bypassed by -N option\n"
2590 "*** host and remaining hosts:\n", tblock->name);
2591 for (host2 = host; host2 != NULL; host2 = host2->next)
2592 debug_printf(" %s [%s]\n", host2->name,
2593 (host2->address == NULL)? US"unset" : host2->address);
2598 /* This is for real. If the host is expired, we don't count it for
2599 hosts_max_retry. This ensures that all hosts must expire before an address
2600 is timed out, unless hosts_max_try_hardlimit (which protects against
2601 lunatic DNS configurations) is reached.
2603 If the host is not expired and we are about to hit the hosts_max_retry
2604 limit, check to see if there is a subsequent hosts with a different MX
2605 value. If so, make that the next host, and don't count this one. This is a
2606 heuristic to make sure that different MXs do get tried. With a normal kind
2607 of retry rule, they would get tried anyway when the earlier hosts were
2608 delayed, but if the domain has a "retry every time" type of rule - as is
2609 often used for the the very large ISPs, that won't happen. */
2613 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
2617 debug_printf("hosts_max_try limit reached with this host\n");
2618 for (h = host; h != NULL; h = h->next)
2619 if (h->mx != host->mx) break;
2623 unexpired_hosts_tried--;
2624 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
2625 "and will be tried\n");
2629 /* Attempt the delivery. */
2631 total_hosts_tried++;
2632 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
2633 expanded_hosts != NULL, &message_defer, FALSE);
2636 OK => connection made, each address contains its result;
2637 message_defer is set for message-specific defers (when all
2638 recipients are marked defer)
2639 DEFER => there was a non-message-specific delivery problem;
2640 ERROR => there was a problem setting up the arguments for a filter,
2641 or there was a problem with expanding added headers
2644 /* If the result is not OK, there was a non-message-specific problem.
2645 If the result is DEFER, we need to write to the logs saying what happened
2646 for this particular host, except in the case of authentication and TLS
2647 failures, where the log has already been written. If all hosts defer a
2648 general message is written at the end. */
2650 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL &&
2651 first_addr->basic_errno != ERRNO_TLSFAILURE)
2652 write_logs(first_addr, host);
2654 /* If STARTTLS was accepted, but there was a failure in setting up the
2655 TLS session (usually a certificate screwup), and the host is not in
2656 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
2657 TLS forcibly turned off. We have to start from scratch with a new SMTP
2658 connection. That's why the retry is done from here, not from within
2659 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
2660 session, so the in-clear transmission after those errors, if permitted,
2661 happens inside smtp_deliver().] */
2664 if (rc == DEFER && first_addr->basic_errno == ERRNO_TLSFAILURE &&
2665 ob->tls_tempfail_tryclear &&
2666 verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
2667 host->address, NULL) != OK)
2669 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
2670 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
2671 first_addr = prepare_addresses(addrlist, host);
2672 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
2673 expanded_hosts != NULL, &message_defer, TRUE);
2674 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
2675 write_logs(first_addr, host);
2680 /* Delivery attempt finished */
2682 rs = (rc == OK)? US"OK" : (rc == DEFER)? US"DEFER" : (rc == ERROR)?
2685 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
2686 message_id, host->name, host->address, addrlist->address,
2687 (addrlist->next == NULL)? "" : " (& others)", rs);
2689 /* Release serialization if set up */
2691 if (serialized) enq_end(serialize_key);
2693 /* If the result is DEFER, or if a host retry record is known to exist, we
2694 need to add an item to the retry chain for updating the retry database
2695 at the end of delivery. We only need to add the item to the top address,
2696 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
2697 for any other delivery attempts using the same address. (It is copied into
2698 the unusable tree at the outer level, so even if different address blocks
2699 contain the same address, it still won't get tried again.) */
2701 if (rc == DEFER || retry_host_key != NULL)
2703 int delete_flag = (rc != DEFER)? rf_delete : 0;
2704 if (retry_host_key == NULL)
2706 retry_host_key = ob->retry_include_ip_address?
2707 string_sprintf("T:%S:%s%s", host->name, host->address, pistring) :
2708 string_sprintf("T:%S%s", host->name, pistring);
2711 /* If a delivery of another message over an existing SMTP connection
2712 yields DEFER, we do NOT set up retry data for the host. This covers the
2713 case when there are delays in routing the addresses in the second message
2714 that are so long that the server times out. This is alleviated by not
2715 routing addresses that previously had routing defers when handling an
2716 existing connection, but even so, this case may occur (e.g. if a
2717 previously happily routed address starts giving routing defers). If the
2718 host is genuinely down, another non-continued message delivery will
2719 notice it soon enough. */
2721 if (delete_flag != 0 || !continuing)
2722 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
2724 /* We may have tried an expired host, if its retry time has come; ensure
2725 the status reflects the expiry for the benefit of any other addresses. */
2729 host->status = (host_is_expired)?
2730 hstatus_unusable_expired : hstatus_unusable;
2731 host->why = hwhy_deferred;
2735 /* If message_defer is set (host was OK, but every recipient got deferred
2736 because of some message-specific problem), or if that had happened
2737 previously so that a message retry key exists, add an appropriate item
2738 to the retry chain. Note that if there was a message defer but now there is
2739 a host defer, the message defer record gets deleted. That seems perfectly
2740 reasonable. Also, stop the message from being remembered as waiting
2743 if (message_defer || retry_message_key != NULL)
2745 int delete_flag = message_defer? 0 : rf_delete;
2746 if (retry_message_key == NULL)
2748 retry_message_key = ob->retry_include_ip_address?
2749 string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
2751 string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
2753 retry_add_item(addrlist, retry_message_key,
2754 rf_message | rf_host | delete_flag);
2755 host->update_waiting = FALSE;
2758 /* Any return other than DEFER (that is, OK or ERROR) means that the
2759 addresses have got their final statuses filled in for this host. In the OK
2760 case, see if any of them are deferred. */
2764 for (addr = addrlist; addr != NULL; addr = addr->next)
2766 if (addr->transport_return == DEFER)
2768 some_deferred = TRUE;
2774 /* If no addresses deferred or the result was ERROR, return. We do this for
2775 ERROR because a failing filter set-up or add_headers expansion is likely to
2776 fail for any host we try. */
2778 if (rc == ERROR || (rc == OK && !some_deferred))
2780 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
2781 return TRUE; /* Each address has its status */
2784 /* If the result was DEFER or some individual addresses deferred, let
2785 the loop run to try other hosts with the deferred addresses, except for the
2786 case when we were trying to deliver down an existing channel and failed.
2787 Don't try any other hosts in this case. */
2789 if (continuing) break;
2791 /* If the whole delivery, or some individual addresses, were deferred and
2792 there are more hosts that could be tried, do not count this host towards
2793 the hosts_max_try limit if the age of the message is greater than the
2794 maximum retry time for this host. This means we may try try all hosts,
2795 ignoring the limit, when messages have been around for some time. This is
2796 important because if we don't try all hosts, the address will never time
2797 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
2799 if ((rc == DEFER || some_deferred) && nexthost != NULL)
2802 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
2804 if (retry != NULL && retry->rules != NULL)
2806 retry_rule *last_rule;
2807 for (last_rule = retry->rules;
2808 last_rule->next != NULL;
2809 last_rule = last_rule->next);
2810 timedout = time(NULL) - received_time > last_rule->timeout;
2812 else timedout = TRUE; /* No rule => timed out */
2816 unexpired_hosts_tried--;
2817 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
2818 "hosts_max_try (message older than host's retry time)\n");
2821 } /* End of loop for trying multiple hosts. */
2823 /* This is the end of the loop that repeats iff expired is TRUE and
2824 ob->delay_after_cutoff is FALSE. The second time round we will
2825 try those hosts that haven't been tried since the message arrived. */
2829 debug_printf("all IP addresses skipped or deferred at least one address\n");
2830 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
2831 debug_printf("retrying IP addresses not tried since message arrived\n");
2836 /* Get here if all IP addresses are skipped or defer at least one address. In
2837 MUA wrapper mode, this will happen only for connection or other non-message-
2838 specific failures. Force the delivery status for all addresses to FAIL. */
2842 for (addr = addrlist; addr != NULL; addr = addr->next)
2843 addr->transport_return = FAIL;
2847 /* In the normal, non-wrapper case, add a standard message to each deferred
2848 address if there hasn't been an error, that is, if it hasn't actually been
2849 tried this time. The variable "expired" will be FALSE if any deliveries were
2850 actually tried, or if there was at least one host that was not expired. That
2851 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
2852 a delivery has been tried, an error code will be set, and the failing of the
2853 message is handled by the retry code later.
2855 If queue_smtp is set, or this transport was called to send a subsequent message
2856 down an existing TCP/IP connection, and something caused the host not to be
2857 found, we end up here, but can detect these cases and handle them specially. */
2859 for (addr = addrlist; addr != NULL; addr = addr->next)
2861 /* If host is not NULL, it means that we stopped processing the host list
2862 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
2863 means we need to behave as if some hosts were skipped because their retry
2864 time had not come. Specifically, this prevents the address from timing out.
2865 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
2866 hosts were tried. */
2870 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
2873 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
2874 "hosts were tried\n");
2879 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
2880 setflag(addr, af_retry_skipped);
2884 if (queue_smtp) /* no deliveries attempted */
2886 addr->transport_return = DEFER;
2887 addr->basic_errno = 0;
2888 addr->message = US"SMTP delivery explicitly queued";
2891 else if (addr->transport_return == DEFER &&
2892 (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0) &&
2893 addr->message == NULL)
2895 addr->basic_errno = ERRNO_HRETRY;
2896 if (continue_hostname != NULL)
2898 addr->message = US"no host found for existing SMTP connection";
2902 setflag(addr, af_pass_message); /* This is not a security risk */
2903 addr->message = (ob->delay_after_cutoff)?
2904 US"retry time not reached for any host after a long failure period" :
2905 US"all hosts have been failing for a long time and were last tried "
2906 "after this message arrived";
2908 /* If we are already using fallback hosts, or there are no fallback hosts
2909 defined, convert the result to FAIL to cause a bounce. */
2911 if (addr->host_list == addr->fallback_hosts ||
2912 addr->fallback_hosts == NULL)
2913 addr->transport_return = FAIL;
2917 if (hosts_retry == hosts_total)
2918 addr->message = US"retry time not reached for any host";
2919 else if (hosts_fail == hosts_total)
2920 addr->message = US"all host address lookups failed permanently";
2921 else if (hosts_defer == hosts_total)
2922 addr->message = US"all host address lookups failed temporarily";
2923 else if (hosts_serial == hosts_total)
2924 addr->message = US"connection limit reached for all hosts";
2925 else if (hosts_fail+hosts_defer == hosts_total)
2926 addr->message = US"all host address lookups failed";
2927 else addr->message = US"some host address lookups failed and retry time "
2928 "not reached for other hosts or connection limit reached";
2933 /* Update the database which keeps information about which messages are waiting
2934 for which hosts to become available. Each host in the list has a flag which is
2935 set if the data is to be updated. For some message-specific errors, the flag is
2936 turned off because we don't want follow-on deliveries in those cases. */
2938 transport_update_waiting(hostlist, tblock->name);
2942 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
2944 return TRUE; /* Each address has its status */
2947 /* End of transport/smtp.c */
git://git.exim.org / exim.git / blob