1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2012 */
6 /* See the file NOTICE for conditions of use and distribution. */
12 #define PENDING_DEFER (PENDING + DEFER)
13 #define PENDING_OK (PENDING + OK)
16 /* Options specific to the smtp transport. This transport also supports LMTP
17 over TCP/IP. The options must be in alphabetic order (note that "_" comes
18 before the lower case letters). Some live in the transport_instance block so as
19 to be publicly visible; these are flagged with opt_public. */
21 optionlist smtp_transport_options[] = {
22 { "address_retry_include_sender", opt_bool,
23 (void *)offsetof(smtp_transport_options_block, address_retry_include_sender) },
24 { "allow_localhost", opt_bool,
25 (void *)offsetof(smtp_transport_options_block, allow_localhost) },
26 { "authenticated_sender", opt_stringptr,
27 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
28 { "authenticated_sender_force", opt_bool,
29 (void *)offsetof(smtp_transport_options_block, authenticated_sender_force) },
30 { "command_timeout", opt_time,
31 (void *)offsetof(smtp_transport_options_block, command_timeout) },
32 { "connect_timeout", opt_time,
33 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
34 { "connection_max_messages", opt_int | opt_public,
35 (void *)offsetof(transport_instance, connection_max_messages) },
36 { "data_timeout", opt_time,
37 (void *)offsetof(smtp_transport_options_block, data_timeout) },
38 { "delay_after_cutoff", opt_bool,
39 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
41 { "dkim_canon", opt_stringptr,
42 (void *)offsetof(smtp_transport_options_block, dkim_canon) },
43 { "dkim_domain", opt_stringptr,
44 (void *)offsetof(smtp_transport_options_block, dkim_domain) },
45 { "dkim_private_key", opt_stringptr,
46 (void *)offsetof(smtp_transport_options_block, dkim_private_key) },
47 { "dkim_selector", opt_stringptr,
48 (void *)offsetof(smtp_transport_options_block, dkim_selector) },
49 { "dkim_sign_headers", opt_stringptr,
50 (void *)offsetof(smtp_transport_options_block, dkim_sign_headers) },
51 { "dkim_strict", opt_stringptr,
52 (void *)offsetof(smtp_transport_options_block, dkim_strict) },
54 { "dns_qualify_single", opt_bool,
55 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
56 { "dns_search_parents", opt_bool,
57 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
58 { "dscp", opt_stringptr,
59 (void *)offsetof(smtp_transport_options_block, dscp) },
60 { "fallback_hosts", opt_stringptr,
61 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
62 { "final_timeout", opt_time,
63 (void *)offsetof(smtp_transport_options_block, final_timeout) },
64 { "gethostbyname", opt_bool,
65 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
67 /* These are no longer honoured, as of Exim 4.80; for now, we silently
68 ignore; a later release will warn, and a later-still release will remove
69 these options, so that using them becomes an error. */
70 { "gnutls_require_kx", opt_stringptr,
71 (void *)offsetof(smtp_transport_options_block, gnutls_require_kx) },
72 { "gnutls_require_mac", opt_stringptr,
73 (void *)offsetof(smtp_transport_options_block, gnutls_require_mac) },
74 { "gnutls_require_protocols", opt_stringptr,
75 (void *)offsetof(smtp_transport_options_block, gnutls_require_proto) },
77 { "helo_data", opt_stringptr,
78 (void *)offsetof(smtp_transport_options_block, helo_data) },
79 { "hosts", opt_stringptr,
80 (void *)offsetof(smtp_transport_options_block, hosts) },
81 { "hosts_avoid_esmtp", opt_stringptr,
82 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
83 { "hosts_avoid_pipelining", opt_stringptr,
84 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
86 { "hosts_avoid_tls", opt_stringptr,
87 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
89 { "hosts_max_try", opt_int,
90 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
91 { "hosts_max_try_hardlimit", opt_int,
92 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
94 { "hosts_nopass_tls", opt_stringptr,
95 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
97 { "hosts_override", opt_bool,
98 (void *)offsetof(smtp_transport_options_block, hosts_override) },
99 { "hosts_randomize", opt_bool,
100 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
101 { "hosts_require_auth", opt_stringptr,
102 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
104 { "hosts_require_tls", opt_stringptr,
105 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
107 { "hosts_try_auth", opt_stringptr,
108 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
109 { "interface", opt_stringptr,
110 (void *)offsetof(smtp_transport_options_block, interface) },
111 { "keepalive", opt_bool,
112 (void *)offsetof(smtp_transport_options_block, keepalive) },
113 { "lmtp_ignore_quota", opt_bool,
114 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
115 { "max_rcpt", opt_int | opt_public,
116 (void *)offsetof(transport_instance, max_addresses) },
117 { "multi_domain", opt_bool | opt_public,
118 (void *)offsetof(transport_instance, multi_domain) },
119 { "port", opt_stringptr,
120 (void *)offsetof(smtp_transport_options_block, port) },
121 { "protocol", opt_stringptr,
122 (void *)offsetof(smtp_transport_options_block, protocol) },
123 { "retry_include_ip_address", opt_bool,
124 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
125 { "serialize_hosts", opt_stringptr,
126 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
127 { "size_addition", opt_int,
128 (void *)offsetof(smtp_transport_options_block, size_addition) }
130 ,{ "tls_certificate", opt_stringptr,
131 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
132 { "tls_crl", opt_stringptr,
133 (void *)offsetof(smtp_transport_options_block, tls_crl) },
134 { "tls_dh_min_bits", opt_int,
135 (void *)offsetof(smtp_transport_options_block, tls_dh_min_bits) },
136 { "tls_privatekey", opt_stringptr,
137 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
138 { "tls_require_ciphers", opt_stringptr,
139 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
140 { "tls_sni", opt_stringptr,
141 (void *)offsetof(smtp_transport_options_block, tls_sni) },
142 { "tls_tempfail_tryclear", opt_bool,
143 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
144 { "tls_verify_certificates", opt_stringptr,
145 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) }
149 /* Size of the options list. An extern variable has to be used so that its
150 address can appear in the tables drtables.c. */
152 int smtp_transport_options_count =
153 sizeof(smtp_transport_options)/sizeof(optionlist);
155 /* Default private options block for the smtp transport. */
157 smtp_transport_options_block smtp_transport_option_defaults = {
159 NULL, /* fallback_hosts */
161 NULL, /* fallback_hostlist */
162 NULL, /* authenticated_sender */
163 US"$primary_hostname", /* helo_data */
164 NULL, /* interface */
166 US"smtp", /* protocol */
168 NULL, /* serialize_hosts */
169 NULL, /* hosts_try_auth */
170 NULL, /* hosts_require_auth */
171 NULL, /* hosts_require_tls */
172 NULL, /* hosts_avoid_tls */
173 NULL, /* hosts_avoid_pipelining */
174 NULL, /* hosts_avoid_esmtp */
175 NULL, /* hosts_nopass_tls */
176 5*60, /* command_timeout */
177 5*60, /* connect_timeout; shorter system default overrides */
178 5*60, /* data timeout */
179 10*60, /* final timeout */
180 1024, /* size_addition */
181 5, /* hosts_max_try */
182 50, /* hosts_max_try_hardlimit */
183 TRUE, /* address_retry_include_sender */
184 FALSE, /* allow_localhost */
185 FALSE, /* authenticated_sender_force */
186 FALSE, /* gethostbyname */
187 TRUE, /* dns_qualify_single */
188 FALSE, /* dns_search_parents */
189 TRUE, /* delay_after_cutoff */
190 FALSE, /* hosts_override */
191 FALSE, /* hosts_randomize */
192 TRUE, /* keepalive */
193 FALSE, /* lmtp_ignore_quota */
194 TRUE /* retry_include_ip_address */
196 ,NULL, /* tls_certificate */
198 NULL, /* tls_privatekey */
199 NULL, /* tls_require_ciphers */
200 NULL, /* gnutls_require_kx */
201 NULL, /* gnutls_require_mac */
202 NULL, /* gnutls_require_proto */
204 NULL, /* tls_verify_certificates */
205 EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
206 /* tls_dh_min_bits */
207 TRUE /* tls_tempfail_tryclear */
210 ,NULL, /* dkim_canon */
211 NULL, /* dkim_domain */
212 NULL, /* dkim_private_key */
213 NULL, /* dkim_selector */
214 NULL, /* dkim_sign_headers */
215 NULL /* dkim_strict */
222 static uschar *smtp_command; /* Points to last cmd for error messages */
223 static uschar *mail_command; /* Points to MAIL cmd for error messages */
224 static BOOL update_waiting; /* TRUE to update the "wait" database */
227 /*************************************************
228 * Setup entry point *
229 *************************************************/
231 /* This function is called when the transport is about to be used,
232 but before running it in a sub-process. It is used for two things:
234 (1) To set the fallback host list in addresses, when delivering.
235 (2) To pass back the interface, port, protocol, and other options, for use
236 during callout verification.
239 tblock pointer to the transport instance block
240 addrlist list of addresses about to be transported
241 tf if not NULL, pointer to block in which to return options
242 uid the uid that will be set (not used)
243 gid the gid that will be set (not used)
244 errmsg place for error message (not used)
246 Returns: OK always (FAIL, DEFER not used)
250 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
251 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
253 smtp_transport_options_block *ob =
254 (smtp_transport_options_block *)(tblock->options_block);
256 errmsg = errmsg; /* Keep picky compilers happy */
260 /* Pass back options if required. This interface is getting very messy. */
264 tf->interface = ob->interface;
266 tf->protocol = ob->protocol;
267 tf->hosts = ob->hosts;
268 tf->hosts_override = ob->hosts_override;
269 tf->hosts_randomize = ob->hosts_randomize;
270 tf->gethostbyname = ob->gethostbyname;
271 tf->qualify_single = ob->dns_qualify_single;
272 tf->search_parents = ob->dns_search_parents;
273 tf->helo_data = ob->helo_data;
276 /* Set the fallback host list for all the addresses that don't have fallback
277 host lists, provided that the local host wasn't present in the original host
280 if (!testflag(addrlist, af_local_host_removed))
282 for (; addrlist != NULL; addrlist = addrlist->next)
283 if (addrlist->fallback_hosts == NULL)
284 addrlist->fallback_hosts = ob->fallback_hostlist;
292 /*************************************************
293 * Initialization entry point *
294 *************************************************/
296 /* Called for each instance, after its options have been read, to
297 enable consistency checks to be done, or anything else that needs
300 Argument: pointer to the transport instance block
305 smtp_transport_init(transport_instance *tblock)
307 smtp_transport_options_block *ob =
308 (smtp_transport_options_block *)(tblock->options_block);
310 /* Retry_use_local_part defaults FALSE if unset */
312 if (tblock->retry_use_local_part == TRUE_UNSET)
313 tblock->retry_use_local_part = FALSE;
315 /* Set the default port according to the protocol */
317 if (ob->port == NULL)
318 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
319 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
321 /* Set up the setup entry point, to be called before subprocesses for this
324 tblock->setup = smtp_transport_setup;
326 /* Complain if any of the timeouts are zero. */
328 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
329 ob->final_timeout <= 0)
330 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
331 "command, data, or final timeout value is zero for %s transport",
334 /* If hosts_override is set and there are local hosts, set the global
335 flag that stops verify from showing router hosts. */
337 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
339 /* If there are any fallback hosts listed, build a chain of host items
340 for them, but do not do any lookups at this time. */
342 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
349 /*************************************************
350 * Set delivery info into all active addresses *
351 *************************************************/
353 /* Only addresses whose status is >= PENDING are relevant. A lesser
354 status means that an address is not currently being processed.
357 addrlist points to a chain of addresses
358 errno_value to put in each address's errno field
359 msg to put in each address's message field
360 rc to put in each address's transport_return field
361 pass_message if TRUE, set the "pass message" flag in the address
363 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
364 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
365 this particular type of timeout.
371 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
376 if (errno_value == ERRNO_CONNECTTIMEOUT)
378 errno_value = ETIMEDOUT;
379 orvalue = RTEF_CTOUT;
381 for (addr = addrlist; addr != NULL; addr = addr->next)
383 if (addr->transport_return < PENDING) continue;
384 addr->basic_errno = errno_value;
385 addr->more_errno |= orvalue;
389 if (pass_message) setflag(addr, af_pass_message);
391 addr->transport_return = rc;
397 /*************************************************
398 * Check an SMTP response *
399 *************************************************/
401 /* This function is given an errno code and the SMTP response buffer
402 to analyse, together with the host identification for generating messages. It
403 sets an appropriate message and puts the first digit of the response code into
404 the yield variable. If no response was actually read, a suitable digit is
408 host the current host, to get its name for messages
409 errno_value pointer to the errno value
410 more_errno from the top address for use with ERRNO_FILTER_FAIL
411 buffer the SMTP response buffer
412 yield where to put a one-digit SMTP response code
413 message where to put an errror message
414 pass_message set TRUE if message is an SMTP response
416 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
419 static BOOL check_response(host_item *host, int *errno_value, int more_errno,
420 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
424 if (smtp_use_pipelining &&
425 (Ustrcmp(smtp_command, "MAIL") == 0 ||
426 Ustrcmp(smtp_command, "RCPT") == 0 ||
427 Ustrcmp(smtp_command, "DATA") == 0))
430 *yield = '4'; /* Default setting is to give a temporary error */
432 /* Handle response timeout */
434 if (*errno_value == ETIMEDOUT)
436 *message = US string_sprintf("SMTP timeout while connected to %s [%s] "
437 "after %s%s", host->name, host->address, pl, smtp_command);
438 if (transport_count > 0)
439 *message = US string_sprintf("%s (%d bytes written)", *message,
444 /* Handle malformed SMTP response */
446 if (*errno_value == ERRNO_SMTPFORMAT)
448 uschar *malfresp = string_printing(buffer);
449 while (isspace(*malfresp)) malfresp++;
451 *message = string_sprintf("Malformed SMTP reply (an empty line) from "
452 "%s [%s] in response to %s%s", host->name, host->address, pl,
455 *message = string_sprintf("Malformed SMTP reply from %s [%s] in response "
456 "to %s%s: %s", host->name, host->address, pl, smtp_command, malfresp);
460 /* Handle a failed filter process error; can't send QUIT as we mustn't
463 if (*errno_value == ERRNO_FILTER_FAIL)
465 *message = US string_sprintf("transport filter process failed (%d)%s",
467 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
471 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
474 if (*errno_value == ERRNO_CHHEADER_FAIL)
477 US string_sprintf("failed to expand headers_add or headers_remove: %s",
478 expand_string_message);
482 /* Handle failure to write a complete data block */
484 if (*errno_value == ERRNO_WRITEINCOMPLETE)
486 *message = US string_sprintf("failed to write a data block");
490 /* Handle error responses from the remote mailer. */
494 uschar *s = string_printing(buffer);
495 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
496 "host %s [%s]: %s", pl, smtp_command, host->name, host->address, s);
497 *pass_message = TRUE;
502 /* No data was read. If there is no errno, this must be the EOF (i.e.
503 connection closed) case, which causes deferral. An explicit connection reset
504 error has the same effect. Otherwise, put the host's identity in the message,
505 leaving the errno value to be interpreted as well. In all cases, we have to
506 assume the connection is now dead. */
508 if (*errno_value == 0 || *errno_value == ECONNRESET)
510 *errno_value = ERRNO_SMTPCLOSED;
511 *message = US string_sprintf("Remote host %s [%s] closed connection "
512 "in response to %s%s", host->name, host->address, pl, smtp_command);
514 else *message = US string_sprintf("%s [%s]", host->name, host->address);
521 /*************************************************
522 * Write error message to logs *
523 *************************************************/
525 /* This writes to the main log and to the message log.
528 addr the address item containing error information
529 host the current host
535 write_logs(address_item *addr, host_item *host)
537 if (addr->message != NULL)
539 uschar *message = addr->message;
540 if (addr->basic_errno > 0)
541 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
542 log_write(0, LOG_MAIN, "%s", message);
543 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
548 ((log_extra_selector & LX_outgoing_port) != 0)?
549 string_sprintf("%s [%s]:%d", host->name, host->address,
550 (host->port == PORT_NONE)? 25 : host->port)
552 string_sprintf("%s [%s]", host->name, host->address);
553 log_write(0, LOG_MAIN, "%s %s", msg, strerror(addr->basic_errno));
554 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), msg,
555 strerror(addr->basic_errno));
561 /*************************************************
562 * Synchronize SMTP responses *
563 *************************************************/
565 /* This function is called from smtp_deliver() to receive SMTP responses from
566 the server, and match them up with the commands to which they relate. When
567 PIPELINING is not in use, this function is called after every command, and is
568 therefore somewhat over-engineered, but it is simpler to use a single scheme
569 that works both with and without PIPELINING instead of having two separate sets
572 The set of commands that are buffered up with pipelining may start with MAIL
573 and may end with DATA; in between are RCPT commands that correspond to the
574 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
575 etc.) are never buffered.
577 Errors after MAIL or DATA abort the whole process leaving the response in the
578 buffer. After MAIL, pending responses are flushed, and the original command is
579 re-instated in big_buffer for error messages. For RCPT commands, the remote is
580 permitted to reject some recipient addresses while accepting others. However
581 certain errors clearly abort the whole process. Set the value in
582 transport_return to PENDING_OK if the address is accepted. If there is a
583 subsequent general error, it will get reset accordingly. If not, it will get
584 converted to OK at the end.
587 addrlist the complete address list
588 include_affixes TRUE if affixes include in RCPT
589 sync_addr ptr to the ptr of the one to start scanning at (updated)
590 host the host we are connected to
591 count the number of responses to read
593 include_sender true if 4xx retry is to include the sender it its key
594 pending_MAIL true if the first response is for MAIL
595 pending_DATA 0 if last command sent was not DATA
596 +1 if previously had a good recipient
597 -1 if not previously had a good recipient
598 inblock incoming SMTP block
599 timeout timeout value
600 buffer buffer for reading response
601 buffsize size of buffer
603 Returns: 3 if at least one address had 2xx and one had 5xx
604 2 if at least one address had 5xx but none had 2xx
605 1 if at least one host had a 2xx response, but none had 5xx
606 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
607 -1 timeout while reading RCPT response
608 -2 I/O or other non-response error for RCPT
609 -3 DATA or MAIL failed - errno and buffer set
613 sync_responses(address_item *addrlist, BOOL include_affixes,
614 address_item **sync_addr, host_item *host, int count,
615 BOOL address_retry_include_sender, BOOL pending_MAIL,
616 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
619 address_item *addr = *sync_addr;
622 /* Handle the response for a MAIL command. On error, reinstate the original
623 command in big_buffer for error message use, and flush any further pending
624 responses before returning, except after I/O errors and timeouts. */
629 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
631 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
632 if (errno == 0 && buffer[0] != 0)
634 uschar flushbuffer[4096];
636 if (buffer[0] == '4')
638 save_errno = ERRNO_MAIL4XX;
639 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
643 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
645 && (errno != 0 || flushbuffer[0] == 0))
654 if (pending_DATA) count--; /* Number of RCPT responses to come */
656 /* Read and handle the required number of RCPT responses, matching each one up
657 with an address by scanning for the next address whose status is PENDING_DEFER.
662 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
664 /* The address was accepted */
666 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
669 addr->transport_return = PENDING_OK;
671 /* If af_dr_retry_exists is set, there was a routing delay on this address;
672 ensure that any address-specific retry record is expunged. We do this both
673 for the basic key and for the version that also includes the sender. */
675 if (testflag(addr, af_dr_retry_exists))
677 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
679 retry_add_item(addr, altkey, rf_delete);
680 retry_add_item(addr, addr->address_retry_key, rf_delete);
684 /* Timeout while reading the response */
686 else if (errno == ETIMEDOUT)
688 int save_errno = errno;
689 uschar *message = string_sprintf("SMTP timeout while connected to %s [%s] "
690 "after RCPT TO:<%s>", host->name, host->address,
691 transport_rcpt_address(addr, include_affixes));
692 set_errno(addrlist, save_errno, message, DEFER, FALSE);
693 retry_add_item(addr, addr->address_retry_key, 0);
694 update_waiting = FALSE;
698 /* Handle other errors in obtaining an SMTP response by returning -1. This
699 will cause all the addresses to be deferred. Restore the SMTP command in
700 big_buffer for which we are checking the response, so the error message
703 else if (errno != 0 || buffer[0] == 0)
705 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
706 transport_rcpt_address(addr, include_affixes));
710 /* Handle SMTP permanent and temporary response codes. */
715 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
716 "host %s [%s]: %s", transport_rcpt_address(addr, include_affixes),
717 host->name, host->address, string_printing(buffer));
718 setflag(addr, af_pass_message);
719 deliver_msglog("%s %s\n", tod_stamp(tod_log), addr->message);
721 /* The response was 5xx */
723 if (buffer[0] == '5')
725 addr->transport_return = FAIL;
729 /* The response was 4xx */
733 addr->transport_return = DEFER;
734 addr->basic_errno = ERRNO_RCPT4XX;
735 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
737 /* Log temporary errors if there are more hosts to be tried. */
739 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", addr->message);
741 /* Do not put this message on the list of those waiting for specific
742 hosts, as otherwise it is likely to be tried too often. */
744 update_waiting = FALSE;
746 /* Add a retry item for the address so that it doesn't get tried again
747 too soon. If address_retry_include_sender is true, add the sender address
750 if (address_retry_include_sender)
752 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
754 retry_add_item(addr, altkey, 0);
756 else retry_add_item(addr, addr->address_retry_key, 0);
759 } /* Loop for next RCPT response */
761 /* Update where to start at for the next block of responses, unless we
762 have already handled all the addresses. */
764 if (addr != NULL) *sync_addr = addr->next;
766 /* Handle a response to DATA. If we have not had any good recipients, either
767 previously or in this block, the response is ignored. */
769 if (pending_DATA != 0 &&
770 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
775 if (pending_DATA > 0 || (yield & 1) != 0)
777 if (errno == 0 && buffer[0] == '4')
779 errno = ERRNO_DATA4XX;
780 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
784 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
785 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
786 "is in use and there were no good recipients\n", msg);
789 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
790 present) received 3xx. If any RCPTs were handled and yielded anything other
791 than 4xx, yield will be set non-zero. */
798 /*************************************************
799 * Deliver address list to given host *
800 *************************************************/
802 /* If continue_hostname is not null, we get here only when continuing to
803 deliver down an existing channel. The channel was passed as the standard
804 input. TLS is never active on a passed channel; the previous process always
805 closes it down before passing the connection on.
807 Otherwise, we have to make a connection to the remote host, and do the
808 initial protocol exchange.
810 When running as an MUA wrapper, if the sender or any recipient is rejected,
811 temporarily or permanently, we force failure for all recipients.
814 addrlist chain of potential addresses to deliver; only those whose
815 transport_return field is set to PENDING_DEFER are currently
816 being processed; others should be skipped - they have either
817 been delivered to an earlier host or IP address, or been
818 failed by one of them.
819 host host to deliver to
820 host_af AF_INET or AF_INET6
821 port default TCP/IP port to use, in host byte order
822 interface interface to bind to, or NULL
823 tblock transport instance block
824 copy_host TRUE if host set in addr->host_used must be copied, because
825 it is specific to this call of the transport
826 message_defer set TRUE if yield is OK, but all addresses were deferred
827 because of a non-recipient, non-host failure, that is, a
828 4xx response to MAIL FROM, DATA, or ".". This is a defer
829 that is specific to the message.
830 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
831 a second attempt after TLS initialization fails
833 Returns: OK - the connection was made and the delivery attempted;
834 the result for each address is in its data block.
835 DEFER - the connection could not be made, or something failed
836 while setting up the SMTP session, or there was a
837 non-message-specific error, such as a timeout.
838 ERROR - a filter command is specified for this transport,
839 and there was a problem setting it up; OR helo_data
840 or add_headers or authenticated_sender is specified
841 for this transport, and the string failed to expand
845 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
846 uschar *interface, transport_instance *tblock, BOOL copy_host,
847 BOOL *message_defer, BOOL suppress_tls)
850 address_item *sync_addr;
851 address_item *first_addr = addrlist;
856 time_t start_delivery_time = time(NULL);
857 smtp_transport_options_block *ob =
858 (smtp_transport_options_block *)(tblock->options_block);
859 BOOL lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
860 BOOL smtps = strcmpic(ob->protocol, US"smtps") == 0;
862 BOOL send_rset = TRUE;
863 BOOL send_quit = TRUE;
864 BOOL setting_up = TRUE;
865 BOOL completed_address = FALSE;
868 BOOL pass_message = FALSE;
869 smtp_inblock inblock;
870 smtp_outblock outblock;
871 int max_rcpt = tblock->max_addresses;
872 uschar *igquotstr = US"";
873 uschar *local_authenticated_sender = authenticated_sender;
874 uschar *helo_data = NULL;
875 uschar *message = NULL;
876 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
879 uschar inbuffer[4096];
880 uschar outbuffer[1024];
882 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
884 *message_defer = FALSE;
885 smtp_command = US"initial connection";
886 if (max_rcpt == 0) max_rcpt = 999999;
888 /* Set up the buffer for reading SMTP response packets. */
890 inblock.buffer = inbuffer;
891 inblock.buffersize = sizeof(inbuffer);
892 inblock.ptr = inbuffer;
893 inblock.ptrend = inbuffer;
895 /* Set up the buffer for holding SMTP commands while pipelining */
897 outblock.buffer = outbuffer;
898 outblock.buffersize = sizeof(outbuffer);
899 outblock.ptr = outbuffer;
900 outblock.cmd_count = 0;
901 outblock.authenticating = FALSE;
903 /* Reset the parameters of a TLS session. */
908 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
912 /* If an authenticated_sender override has been specified for this transport
913 instance, expand it. If the expansion is forced to fail, and there was already
914 an authenticated_sender for this message, the original value will be used.
915 Other expansion failures are serious. An empty result is ignored, but there is
916 otherwise no check - this feature is expected to be used with LMTP and other
917 cases where non-standard addresses (e.g. without domains) might be required. */
919 if (ob->authenticated_sender != NULL)
921 uschar *new = expand_string(ob->authenticated_sender);
924 if (!expand_string_forcedfail)
926 uschar *message = string_sprintf("failed to expand "
927 "authenticated_sender: %s", expand_string_message);
928 set_errno(addrlist, 0, message, DEFER, FALSE);
932 else if (new[0] != 0) local_authenticated_sender = new;
938 set_errno(addrlist, 0, US"TLS support not available", DEFER, FALSE);
943 /* Make a connection to the host if this isn't a continued delivery, and handle
944 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
945 specially so they can be identified for retries. */
947 if (continue_hostname == NULL)
949 inblock.sock = outblock.sock =
950 smtp_connect(host, host_af, port, interface, ob->connect_timeout,
951 ob->keepalive, ob->dscp); /* This puts port into host->port */
953 if (inblock.sock < 0)
955 set_errno(addrlist, (errno == ETIMEDOUT)? ERRNO_CONNECTTIMEOUT : errno,
960 /* Expand the greeting message while waiting for the initial response. (Makes
961 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
962 delayed till here so that $sending_interface and $sending_port are set. */
964 helo_data = expand_string(ob->helo_data);
966 /* The first thing is to wait for an initial OK response. The dreaded "goto"
967 is nevertheless a reasonably clean way of programming this kind of logic,
968 where you want to escape on any error. */
972 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
973 ob->command_timeout)) goto RESPONSE_FAILED;
975 /* Now check if the helo_data expansion went well, and sign off cleanly if
978 if (helo_data == NULL)
980 uschar *message = string_sprintf("failed to expand helo_data: %s",
981 expand_string_message);
982 set_errno(addrlist, 0, message, DEFER, FALSE);
988 /** Debugging without sending a message
989 addrlist->transport_return = DEFER;
993 /* Errors that occur after this point follow an SMTP command, which is
994 left in big_buffer by smtp_write_command() for use in error messages. */
996 smtp_command = big_buffer;
998 /* Tell the remote who we are...
1000 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1001 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1002 greeting is of this form. The assumption was that the far end supports it
1003 properly... but experience shows that there are some that give 5xx responses,
1004 even though the banner includes "ESMTP" (there's a bloody-minded one that
1005 says "ESMTP not spoken here"). Cope with that case.
1007 September 2000: Time has passed, and it seems reasonable now to always send
1008 EHLO at the start. It is also convenient to make the change while installing
1011 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1012 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1013 would be no way to send out the mails, so there is now a host list
1014 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1015 PIPELINING problem as well. Maybe it can also be useful to cure other
1016 problems with broken servers.
1018 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1019 Then somebody tried it with a Microsoft mailer... It seems that all other
1020 mailers use upper case for some reason (the RFC is quite clear about case
1021 independence) so, for peace of mind, I gave in. */
1023 esmtp = verify_check_this_host(&(ob->hosts_avoid_esmtp), NULL,
1024 host->name, host->address, NULL) != OK;
1026 /* Alas; be careful, since this goto is not an error-out, so conceivably
1027 we might set data between here and the target which we assume to exist
1028 and be usable. I can see this coming back to bite us. */
1033 suppress_tls = FALSE;
1034 ob->tls_tempfail_tryclear = FALSE;
1035 smtp_command = US"SSL-on-connect";
1042 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1043 lmtp? "LHLO" : "EHLO", helo_data) < 0)
1045 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1046 ob->command_timeout))
1048 if (errno != 0 || buffer[0] == 0 || lmtp) goto RESPONSE_FAILED;
1055 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1060 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1062 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1063 ob->command_timeout)) goto RESPONSE_FAILED;
1066 /* Set IGNOREQUOTA if the response to LHLO specifies support and the
1067 lmtp_ignore_quota option was set. */
1069 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1070 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1071 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1073 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1076 tls_offered = esmtp &&
1077 pcre_exec(regex_STARTTLS, NULL, CS buffer, Ustrlen(buffer), 0,
1078 PCRE_EOPT, NULL, 0) >= 0;
1082 /* For continuing deliveries down the same channel, the socket is the standard
1083 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1084 below). Set up the pointer to where subsequent commands will be left, for
1085 error messages. Note that smtp_use_size and smtp_use_pipelining will have been
1086 set from the command line if they were set in the process that passed the
1091 inblock.sock = outblock.sock = fileno(stdin);
1092 smtp_command = big_buffer;
1093 host->port = port; /* Record the port that was used */
1096 /* If TLS is available on this connection, whether continued or not, attempt to
1097 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1098 send another EHLO - the server may give a different answer in secure mode. We
1099 use a separate buffer for reading the response to STARTTLS so that if it is
1100 negative, the original EHLO data is available for subsequent analysis, should
1101 the client not be required to use TLS. If the response is bad, copy the buffer
1102 for error analysis. */
1105 if (tls_offered && !suppress_tls &&
1106 verify_check_this_host(&(ob->hosts_avoid_tls), NULL, host->name,
1107 host->address, NULL) != OK)
1109 uschar buffer2[4096];
1110 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1113 /* If there is an I/O error, transmission of this message is deferred. If
1114 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1115 false, we also defer. However, if there is a temporary rejection of STARTTLS
1116 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1117 STARTTLS, we carry on. This means we will try to send the message in clear,
1118 unless the host is in hosts_require_tls (tested below). */
1120 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1121 ob->command_timeout))
1123 if (errno != 0 || buffer2[0] == 0 ||
1124 (buffer2[0] == '4' && !ob->tls_tempfail_tryclear))
1126 Ustrncpy(buffer, buffer2, sizeof(buffer));
1127 goto RESPONSE_FAILED;
1131 /* STARTTLS accepted: try to negotiate a TLS session. */
1136 int rc = tls_client_start(inblock.sock,
1139 NULL, /* No DH param */
1140 ob->tls_certificate,
1143 ob->tls_verify_certificates,
1145 ob->tls_require_ciphers,
1146 ob->tls_dh_min_bits,
1147 ob->command_timeout);
1149 /* TLS negotiation failed; give an error. From outside, this function may
1150 be called again to try in clear on a new connection, if the options permit
1151 it for this host. */
1155 save_errno = ERRNO_TLSFAILURE;
1156 message = US"failure while setting up TLS session";
1161 /* TLS session is set up */
1163 for (addr = addrlist; addr != NULL; addr = addr->next)
1165 if (addr->transport_return == PENDING_DEFER)
1167 addr->cipher = tls_cipher;
1168 addr->peerdn = tls_peerdn;
1174 /* if smtps, we'll have smtp_command set to something else; always safe to
1176 smtp_command = big_buffer;
1178 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1179 helo_data is null, we are dealing with a connection that was passed from
1180 another process, and so we won't have expanded helo_data above. We have to
1181 expand it here. $sending_ip_address and $sending_port are set up right at the
1182 start of the Exim process (in exim.c). */
1184 if (tls_active >= 0)
1187 if (helo_data == NULL)
1189 helo_data = expand_string(ob->helo_data);
1190 if (helo_data == NULL)
1192 uschar *message = string_sprintf("failed to expand helo_data: %s",
1193 expand_string_message);
1194 set_errno(addrlist, 0, message, DEFER, FALSE);
1200 /* For SMTPS we need to wait for the initial OK response. */
1203 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1204 ob->command_timeout)) goto RESPONSE_FAILED;
1208 greeting_cmd = "EHLO";
1211 greeting_cmd = "HELO";
1213 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1216 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1217 lmtp? "LHLO" : greeting_cmd, helo_data) < 0)
1219 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1220 ob->command_timeout))
1221 goto RESPONSE_FAILED;
1224 /* If the host is required to use a secure channel, ensure that we
1227 else if (verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
1228 host->address, NULL) == OK)
1230 save_errno = ERRNO_TLSREQUIRED;
1231 message = string_sprintf("a TLS session is required for %s [%s], but %s",
1232 host->name, host->address,
1233 tls_offered? "an attempt to start TLS failed" :
1234 "the server did not offer TLS support");
1239 /* If TLS is active, we have just started it up and re-done the EHLO command,
1240 so its response needs to be analyzed. If TLS is not active and this is a
1241 continued session down a previously-used socket, we haven't just done EHLO, so
1244 if (continue_hostname == NULL
1251 uschar *fail_reason = US"server did not advertise AUTH support";
1253 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
1254 lmtp_ignore_quota option was set. */
1256 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1257 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1258 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1260 /* If the response to EHLO specified support for the SIZE parameter, note
1261 this, provided size_addition is non-negative. */
1263 smtp_use_size = esmtp && ob->size_addition >= 0 &&
1264 pcre_exec(regex_SIZE, NULL, CS buffer, Ustrlen(CS buffer), 0,
1265 PCRE_EOPT, NULL, 0) >= 0;
1267 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
1268 the current host, esmtp will be false, so PIPELINING can never be used. If
1269 the current host matches hosts_avoid_pipelining, don't do it. */
1271 smtp_use_pipelining = esmtp &&
1272 verify_check_this_host(&(ob->hosts_avoid_pipelining), NULL, host->name,
1273 host->address, NULL) != OK &&
1274 pcre_exec(regex_PIPELINING, NULL, CS buffer, Ustrlen(CS buffer), 0,
1275 PCRE_EOPT, NULL, 0) >= 0;
1277 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
1278 smtp_use_pipelining? "" : "not ");
1280 /* Note if the response to EHLO specifies support for the AUTH extension.
1281 If it has, check that this host is one we want to authenticate to, and do
1282 the business. The host name and address must be available when the
1283 authenticator's client driver is running. */
1285 smtp_authenticated = FALSE;
1286 require_auth = verify_check_this_host(&(ob->hosts_require_auth), NULL,
1287 host->name, host->address, NULL);
1289 if (esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
1291 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
1292 expand_nmax = -1; /* reset */
1294 /* Must not do this check until after we have saved the result of the
1295 regex match above. */
1297 if (require_auth == OK ||
1298 verify_check_this_host(&(ob->hosts_try_auth), NULL, host->name,
1299 host->address, NULL) == OK)
1302 fail_reason = US"no common mechanisms were found";
1304 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1306 /* Scan the configured authenticators looking for one which is configured
1307 for use as a client, which is not suppressed by client_condition, and
1308 whose name matches an authentication mechanism supported by the server.
1309 If one is found, attempt to authenticate by calling its client function.
1312 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1316 (au->client_condition != NULL &&
1317 !expand_check_condition(au->client_condition, au->name,
1318 US"client authenticator")))
1320 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1322 (au->client)? "client_condition is false" :
1323 "not configured as a client");
1327 /* Loop to scan supported server mechanisms */
1332 int len = Ustrlen(au->public_name);
1333 while (isspace(*p)) p++;
1335 if (strncmpic(au->public_name, p, len) != 0 ||
1336 (p[len] != 0 && !isspace(p[len])))
1338 while (*p != 0 && !isspace(*p)) p++;
1342 /* Found data for a listed mechanism. Call its client entry. Set
1343 a flag in the outblock so that data is overwritten after sending so
1344 that reflections don't show it. */
1346 fail_reason = US"authentication attempt(s) failed";
1347 outblock.authenticating = TRUE;
1348 rc = (au->info->clientcode)(au, &inblock, &outblock,
1349 ob->command_timeout, buffer, sizeof(buffer));
1350 outblock.authenticating = FALSE;
1351 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1354 /* A temporary authentication failure must hold up delivery to
1355 this host. After a permanent authentication failure, we carry on
1356 to try other authentication methods. If all fail hard, try to
1357 deliver the message unauthenticated unless require_auth was set. */
1362 smtp_authenticated = TRUE; /* stops the outer loop */
1365 /* Failure after writing a command */
1370 /* Failure after reading a response */
1373 if (errno != 0 || buffer[0] != '5') goto RESPONSE_FAILED;
1374 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1375 au->name, host->name, host->address, buffer);
1378 /* Failure by some other means. In effect, the authenticator
1379 decided it wasn't prepared to handle this case. Typically this
1380 is the result of "fail" in an expansion string. Do we need to
1381 log anything here? Feb 2006: a message is now put in the buffer
1382 if logging is required. */
1386 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1387 "authentication H=%s [%s] %s", au->name, host->name,
1388 host->address, buffer);
1391 /* Internal problem, message in buffer. */
1395 set_errno(addrlist, 0, string_copy(buffer), DEFER, FALSE);
1399 break; /* If not authenticated, try next authenticator */
1400 } /* Loop for scanning supported server mechanisms */
1401 } /* Loop for further authenticators */
1405 /* If we haven't authenticated, but are required to, give up. */
1407 if (require_auth == OK && !smtp_authenticated)
1410 set_errno(addrlist, ERRNO_AUTHFAIL,
1411 string_sprintf("authentication required but %s", fail_reason), DEFER,
1417 /* The setting up of the SMTP call is now complete. Any subsequent errors are
1418 message-specific. */
1422 /* If there is a filter command specified for this transport, we can now
1423 set it up. This cannot be done until the identify of the host is known. */
1425 if (tblock->filter_command != NULL)
1429 sprintf(CS buffer, "%.50s transport", tblock->name);
1430 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
1431 TRUE, DEFER, addrlist, buffer, NULL);
1432 transport_filter_timeout = tblock->filter_timeout;
1434 /* On failure, copy the error to all addresses, abandon the SMTP call, and
1439 set_errno(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
1447 /* For messages that have more than the maximum number of envelope recipients,
1448 we want to send several transactions down the same SMTP connection. (See
1449 comments in deliver.c as to how this reconciles, heuristically, with
1450 remote_max_parallel.) This optimization was added to Exim after the following
1451 code was already working. The simplest way to put it in without disturbing the
1452 code was to use a goto to jump back to this point when there is another
1453 transaction to handle. */
1456 sync_addr = first_addr;
1460 completed_address = FALSE;
1463 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
1464 qualification, send it, adding something to the message size to allow for
1465 imprecision and things that get added en route. Exim keeps the number of lines
1466 in a message, so we can give an accurate value for the original message, but we
1467 need some additional to handle added headers. (Double "." characters don't get
1468 included in the count.) */
1475 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
1479 /* Add the authenticated sender address if present */
1481 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1482 local_authenticated_sender != NULL)
1484 string_format(p, sizeof(buffer) - (p-buffer), " AUTH=%s",
1485 auth_xtextencode(local_authenticated_sender,
1486 Ustrlen(local_authenticated_sender)));
1489 /* From here until we send the DATA command, we can make use of PIPELINING
1490 if the server host supports it. The code has to be able to check the responses
1491 at any point, for when the buffer fills up, so we write it totally generally.
1492 When PIPELINING is off, each command written reports that it has flushed the
1495 pending_MAIL = TRUE; /* The block starts with MAIL */
1497 rc = smtp_write_command(&outblock, smtp_use_pipelining,
1498 "MAIL FROM:<%s>%s\r\n", return_path, buffer);
1499 mail_command = string_copy(big_buffer); /* Save for later error message */
1503 case -1: /* Transmission error */
1506 case +1: /* Block was sent */
1507 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1508 ob->command_timeout))
1510 if (errno == 0 && buffer[0] == '4')
1512 errno = ERRNO_MAIL4XX;
1513 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1515 goto RESPONSE_FAILED;
1517 pending_MAIL = FALSE;
1521 /* Pass over all the relevant recipient addresses for this host, which are the
1522 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
1523 several before we have to read the responses for those seen so far. This
1524 checking is done by a subroutine because it also needs to be done at the end.
1525 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
1526 the next one if not all are sent.
1528 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
1529 last address because we want to abort if any recipients have any kind of
1530 problem, temporary or permanent. We know that all recipient addresses will have
1531 the PENDING_DEFER status, because only one attempt is ever made, and we know
1532 that max_rcpt will be large, so all addresses will be done at once. */
1534 for (addr = first_addr;
1535 address_count < max_rcpt && addr != NULL;
1541 if (addr->transport_return != PENDING_DEFER) continue;
1544 no_flush = smtp_use_pipelining && (!mua_wrapper || addr->next != NULL);
1546 /* Now send the RCPT command, and process outstanding responses when
1547 necessary. After a timeout on RCPT, we just end the function, leaving the
1548 yield as OK, because this error can often mean that there is a problem with
1549 just one address, so we don't want to delay the host. */
1551 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s\r\n",
1552 transport_rcpt_address(addr, tblock->rcpt_include_affixes), igquotstr);
1553 if (count < 0) goto SEND_FAILED;
1556 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
1557 &sync_addr, host, count, ob->address_retry_include_sender,
1558 pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
1561 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1562 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1565 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1566 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1567 case 0: /* No 2xx or 5xx, but no probs */
1570 case -1: goto END_OFF; /* Timeout on RCPT */
1571 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
1573 pending_MAIL = FALSE; /* Dealt with MAIL */
1575 } /* Loop for next address */
1577 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
1578 permanently or temporarily. We should have flushed and synced after the last
1583 address_item *badaddr;
1584 for (badaddr = first_addr; badaddr != NULL; badaddr = badaddr->next)
1586 if (badaddr->transport_return != PENDING_OK) break;
1588 if (badaddr != NULL)
1590 set_errno(addrlist, 0, badaddr->message, FAIL,
1591 testflag(badaddr, af_pass_message));
1596 /* If ok is TRUE, we know we have got at least one good recipient, and must now
1597 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
1598 have a good recipient buffered up if we are pipelining. We don't want to waste
1599 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
1600 are pipelining. The responses are all handled by sync_responses(). */
1602 if (ok || (smtp_use_pipelining && !mua_wrapper))
1604 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
1605 if (count < 0) goto SEND_FAILED;
1606 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
1607 host, count, ob->address_retry_include_sender, pending_MAIL,
1608 ok? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
1610 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1611 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1614 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1615 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1616 case 0: break; /* No 2xx or 5xx, but no probs */
1618 case -1: goto END_OFF; /* Timeout on RCPT */
1619 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
1623 /* Save the first address of the next batch. */
1627 /* If there were no good recipients (but otherwise there have been no
1628 problems), just set ok TRUE, since we have handled address-specific errors
1629 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
1630 for handling the SMTP dot-handling protocol, flagging to apply to headers as
1631 well as body. Set the appropriate timeout value to be used for each chunk.
1632 (Haven't been able to make it work using select() for writing yet.) */
1634 if (!ok) ok = TRUE; else
1636 sigalrm_seen = FALSE;
1637 transport_write_timeout = ob->data_timeout;
1638 smtp_command = US"sending data block"; /* For error messages */
1639 DEBUG(D_transport|D_v)
1640 debug_printf(" SMTP>> writing message and terminating \".\"\n");
1641 transport_count = 0;
1642 #ifndef DISABLE_DKIM
1643 ok = dkim_transport_write_message(addrlist, inblock.sock,
1644 topt_use_crlf | topt_end_dot | topt_escape_headers |
1645 (tblock->body_only? topt_no_headers : 0) |
1646 (tblock->headers_only? topt_no_body : 0) |
1647 (tblock->return_path_add? topt_add_return_path : 0) |
1648 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1649 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1650 0, /* No size limit */
1651 tblock->add_headers, tblock->remove_headers,
1652 US".", US"..", /* Escaping strings */
1653 tblock->rewrite_rules, tblock->rewrite_existflags,
1654 ob->dkim_private_key, ob->dkim_domain, ob->dkim_selector,
1655 ob->dkim_canon, ob->dkim_strict, ob->dkim_sign_headers
1658 ok = transport_write_message(addrlist, inblock.sock,
1659 topt_use_crlf | topt_end_dot | topt_escape_headers |
1660 (tblock->body_only? topt_no_headers : 0) |
1661 (tblock->headers_only? topt_no_body : 0) |
1662 (tblock->return_path_add? topt_add_return_path : 0) |
1663 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1664 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1665 0, /* No size limit */
1666 tblock->add_headers, tblock->remove_headers,
1667 US".", US"..", /* Escaping strings */
1668 tblock->rewrite_rules, tblock->rewrite_existflags);
1671 /* transport_write_message() uses write() because it is called from other
1672 places to write to non-sockets. This means that under some OS (e.g. Solaris)
1673 it can exit with "Broken pipe" as its error. This really means that the
1674 socket got closed at the far end. */
1676 transport_write_timeout = 0; /* for subsequent transports */
1678 /* Failure can either be some kind of I/O disaster (including timeout),
1679 or the failure of a transport filter or the expansion of added headers. */
1683 buffer[0] = 0; /* There hasn't been a response */
1684 goto RESPONSE_FAILED;
1687 /* We used to send the terminating "." explicitly here, but because of
1688 buffering effects at both ends of TCP/IP connections, you don't gain
1689 anything by keeping it separate, so it might as well go in the final
1690 data buffer for efficiency. This is now done by setting the topt_end_dot
1693 smtp_command = US"end of data";
1695 /* For SMTP, we now read a single response that applies to the whole message.
1696 If it is OK, then all the addresses have been delivered. */
1700 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1702 if (!ok && errno == 0 && buffer[0] == '4')
1704 errno = ERRNO_DATA4XX;
1705 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1709 /* For LMTP, we get back a response for every RCPT command that we sent;
1710 some may be accepted and some rejected. For those that get a response, their
1711 status is fixed; any that are accepted have been handed over, even if later
1712 responses crash - at least, that's how I read RFC 2033.
1714 If all went well, mark the recipient addresses as completed, record which
1715 host/IPaddress they were delivered to, and cut out RSET when sending another
1716 message down the same channel. Write the completed addresses to the journal
1717 now so that they are recorded in case there is a crash of hardware or
1718 software before the spool gets updated. Also record the final SMTP
1719 confirmation if needed (for SMTP only). */
1724 int delivery_time = (int)(time(NULL) - start_delivery_time);
1727 uschar *conf = NULL;
1730 /* Make a copy of the host if it is local to this invocation
1731 of the transport. */
1735 thost = store_get(sizeof(host_item));
1737 thost->name = string_copy(host->name);
1738 thost->address = string_copy(host->address);
1742 /* Set up confirmation if needed - applies only to SMTP */
1744 if ((log_extra_selector & LX_smtp_confirmation) != 0 && !lmtp)
1746 uschar *s = string_printing(buffer);
1747 conf = (s == buffer)? (uschar *)string_copy(s) : s;
1750 /* Process all transported addresses - for LMTP, read a status for
1753 for (addr = addrlist; addr != first_addr; addr = addr->next)
1755 if (addr->transport_return != PENDING_OK) continue;
1757 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
1758 remaining addresses. Otherwise, it's a return code for just the one
1759 address. For temporary errors, add a retry item for the address so that
1760 it doesn't get tried again too soon. */
1764 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1767 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
1768 addr->message = string_sprintf("LMTP error after %s: %s",
1769 big_buffer, string_printing(buffer));
1770 setflag(addr, af_pass_message); /* Allow message to go to user */
1771 if (buffer[0] == '5')
1772 addr->transport_return = FAIL;
1775 errno = ERRNO_DATA4XX;
1776 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1777 addr->transport_return = DEFER;
1778 retry_add_item(addr, addr->address_retry_key, 0);
1782 completed_address = TRUE; /* NOW we can set this flag */
1783 if ((log_extra_selector & LX_smtp_confirmation) != 0)
1785 uschar *s = string_printing(buffer);
1786 conf = (s == buffer)? (uschar *)string_copy(s) : s;
1790 /* SMTP, or success return from LMTP for this address. Pass back the
1791 actual host that was used. */
1793 addr->transport_return = OK;
1794 addr->more_errno = delivery_time;
1795 addr->host_used = thost;
1796 addr->special_action = flag;
1797 addr->message = conf;
1800 /* Update the journal. For homonymic addresses, use the base address plus
1801 the transport name. See lots of comments in deliver.c about the reasons
1802 for the complications when homonyms are involved. Just carry on after
1803 write error, as it may prove possible to update the spool file later. */
1805 if (testflag(addr, af_homonym))
1806 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
1808 sprintf(CS buffer, "%.500s\n", addr->unique);
1810 DEBUG(D_deliver) debug_printf("journalling %s", buffer);
1811 len = Ustrlen(CS buffer);
1812 if (write(journal_fd, buffer, len) != len)
1813 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
1814 "%s: %s", buffer, strerror(errno));
1817 /* Ensure the journal file is pushed out to disk. */
1819 if (EXIMfsync(journal_fd) < 0)
1820 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
1826 /* Handle general (not specific to one address) failures here. The value of ok
1827 is used to skip over this code on the falling through case. A timeout causes a
1828 deferral. Other errors may defer or fail according to the response code, and
1829 may set up a special errno value, e.g. after connection chopped, which is
1830 assumed if errno == 0 and there is no text in the buffer. If control reaches
1831 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
1832 the problem is not related to this specific message. */
1841 send_quit = check_response(host, &save_errno, addrlist->more_errno,
1842 buffer, &code, &message, &pass_message);
1848 message = US string_sprintf("send() to %s [%s] failed: %s",
1849 host->name, host->address, strerror(save_errno));
1853 /* This label is jumped to directly when a TLS negotiation has failed,
1854 or was not done for a host for which it is required. Values will be set
1855 in message and save_errno, and setting_up will always be true. Treat as
1856 a temporary error. */
1863 /* If the failure happened while setting up the call, see if the failure was
1864 a 5xx response (this will either be on connection, or following HELO - a 5xx
1865 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
1866 never going to accept them. For other errors during setting up (timeouts or
1867 whatever), defer all addresses, and yield DEFER, so that the host is not
1868 tried again for a while. */
1871 ok = FALSE; /* For when reached by GOTO */
1877 set_errno(addrlist, save_errno, message, FAIL, pass_message);
1881 set_errno(addrlist, save_errno, message, DEFER, pass_message);
1886 /* We want to handle timeouts after MAIL or "." and loss of connection after
1887 "." specially. They can indicate a problem with the sender address or with
1888 the contents of the message rather than a real error on the connection. These
1889 cases are treated in the same way as a 4xx response. This next bit of code
1890 does the classification. */
1901 message_error = TRUE;
1905 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
1906 Ustrncmp(smtp_command,"end ",4) == 0;
1909 case ERRNO_SMTPCLOSED:
1910 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
1914 message_error = FALSE;
1918 /* Handle the cases that are treated as message errors. These are:
1920 (a) negative response or timeout after MAIL
1921 (b) negative response after DATA
1922 (c) negative response or timeout or dropped connection after "."
1924 It won't be a negative response or timeout after RCPT, as that is dealt
1925 with separately above. The action in all cases is to set an appropriate
1926 error code for all the addresses, but to leave yield set to OK because the
1927 host itself has not failed. Of course, it might in practice have failed
1928 when we've had a timeout, but if so, we'll discover that at the next
1929 delivery attempt. For a temporary error, set the message_defer flag, and
1930 write to the logs for information if this is not the last host. The error
1931 for the last host will be logged as part of the address's log line. */
1935 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
1936 set_errno(addrlist, save_errno, message, (code == '5')? FAIL : DEFER,
1939 /* If there's an errno, the message contains just the identity of
1942 if (code != '5') /* Anything other than 5 is treated as temporary */
1945 message = US string_sprintf("%s: %s", message, strerror(save_errno));
1946 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
1947 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
1948 *message_defer = TRUE;
1952 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
1953 ".", or some other transportation error. We defer all addresses and yield
1954 DEFER, except for the case of failed add_headers expansion, or a transport
1955 filter failure, when the yield should be ERROR, to stop it trying other
1960 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
1961 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
1962 set_errno(addrlist, save_errno, message, DEFER, pass_message);
1968 /* If all has gone well, send_quit will be set TRUE, implying we can end the
1969 SMTP session tidily. However, if there were too many addresses to send in one
1970 message (indicated by first_addr being non-NULL) we want to carry on with the
1971 rest of them. Also, it is desirable to send more than one message down the SMTP
1972 connection if there are several waiting, provided we haven't already sent so
1973 many as to hit the configured limit. The function transport_check_waiting looks
1974 for a waiting message and returns its id. Then transport_pass_socket tries to
1975 set up a continued delivery by passing the socket on to another process. The
1976 variable send_rset is FALSE if a message has just been successfully transfered.
1978 If we are already sending down a continued channel, there may be further
1979 addresses not yet delivered that are aimed at the same host, but which have not
1980 been passed in this run of the transport. In this case, continue_more will be
1981 true, and all we should do is send RSET if necessary, and return, leaving the
1984 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
1985 do not want to continue with other messages down the same channel, because that
1986 can lead to looping between two or more messages, all with the same,
1987 temporarily failing address(es). [The retry information isn't updated yet, so
1988 new processes keep on trying.] We probably also don't want to try more of this
1989 message's addresses either.
1991 If we have started a TLS session, we have to end it before passing the
1992 connection to a new process. However, not all servers can handle this (Exim
1993 can), so we do not pass such a connection on if the host matches
1994 hosts_nopass_tls. */
1997 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
1998 "yield=%d first_address is %sNULL\n", ok, send_quit, send_rset,
1999 continue_more, yield, (first_addr == NULL)? "":"not ");
2001 if (completed_address && ok && send_quit)
2004 if (first_addr != NULL || continue_more ||
2007 verify_check_this_host(&(ob->hosts_nopass_tls), NULL, host->name,
2008 host->address, NULL) != OK)
2010 transport_check_waiting(tblock->name, host->name,
2011 tblock->connection_max_messages, new_message_id, &more)
2019 if (! (ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
2021 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
2022 host->address, strerror(save_errno));
2025 else if (! (ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2026 ob->command_timeout)))
2029 send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
2033 DEBUG(D_transport) debug_printf("%s\n", msg);
2038 /* Either RSET was not needed, or it succeeded */
2042 if (first_addr != NULL) /* More addresses still to be sent */
2043 { /* in this run of the transport */
2044 continue_sequence++; /* Causes * in logging */
2047 if (continue_more) return yield; /* More addresses for another run */
2049 /* Pass the socket to a new Exim process. Before doing so, we must shut
2050 down TLS. Not all MTAs allow for the continuation of the SMTP session
2051 when TLS is shut down. We test for this by sending a new EHLO. If we
2052 don't get a good response, we don't attempt to pass the socket on. */
2055 if (tls_active >= 0)
2061 ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
2062 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2063 ob->command_timeout);
2067 /* If the socket is successfully passed, we musn't send QUIT (or
2068 indeed anything!) from here. */
2070 if (ok && transport_pass_socket(tblock->name, host->name, host->address,
2071 new_message_id, inblock.sock))
2077 /* If RSET failed and there are addresses left, they get deferred. */
2079 else set_errno(first_addr, errno, msg, DEFER, FALSE);
2083 /* End off tidily with QUIT unless the connection has died or the socket has
2084 been passed to another process. There has been discussion on the net about what
2085 to do after sending QUIT. The wording of the RFC suggests that it is necessary
2086 to wait for a response, but on the other hand, there isn't anything one can do
2087 with an error response, other than log it. Exim used to do that. However,
2088 further discussion suggested that it is positively advantageous not to wait for
2089 the response, but to close the session immediately. This is supposed to move
2090 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
2091 load from the server. (Hosts that are both servers and clients may not see much
2092 difference, of course.) Further discussion indicated that this was safe to do
2093 on Unix systems which have decent implementations of TCP/IP that leave the
2094 connection around for a while (TIME_WAIT) after the application has gone away.
2095 This enables the response sent by the server to be properly ACKed rather than
2096 timed out, as can happen on broken TCP/IP implementations on other OS.
2098 This change is being made on 31-Jul-98. After over a year of trouble-free
2099 operation, the old commented-out code was removed on 17-Sep-99. */
2102 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2110 /* Close the socket, and return the appropriate value, first setting
2111 continue_transport and continue_hostname NULL to prevent any other addresses
2112 that may include the host from trying to re-use a continuation socket. This
2113 works because the NULL setting is passed back to the calling process, and
2114 remote_max_parallel is forced to 1 when delivering over an existing connection,
2116 If all went well and continue_more is set, we shouldn't actually get here if
2117 there are further addresses, as the return above will be taken. However,
2118 writing RSET might have failed, or there may be other addresses whose hosts are
2119 specified in the transports, and therefore not visible at top level, in which
2120 case continue_more won't get set. */
2122 (void)close(inblock.sock);
2123 continue_transport = NULL;
2124 continue_hostname = NULL;
2131 /*************************************************
2132 * Closedown entry point *
2133 *************************************************/
2135 /* This function is called when exim is passed an open smtp channel
2136 from another incarnation, but the message which it has been asked
2137 to deliver no longer exists. The channel is on stdin.
2139 We might do fancy things like looking for another message to send down
2140 the channel, but if the one we sought has gone, it has probably been
2141 delivered by some other process that itself will seek further messages,
2142 so just close down our connection.
2144 Argument: pointer to the transport instance block
2149 smtp_transport_closedown(transport_instance *tblock)
2151 smtp_transport_options_block *ob =
2152 (smtp_transport_options_block *)(tblock->options_block);
2153 smtp_inblock inblock;
2154 smtp_outblock outblock;
2156 uschar inbuffer[4096];
2157 uschar outbuffer[16];
2159 inblock.sock = fileno(stdin);
2160 inblock.buffer = inbuffer;
2161 inblock.buffersize = sizeof(inbuffer);
2162 inblock.ptr = inbuffer;
2163 inblock.ptrend = inbuffer;
2165 outblock.sock = inblock.sock;
2166 outblock.buffersize = sizeof(outbuffer);
2167 outblock.buffer = outbuffer;
2168 outblock.ptr = outbuffer;
2169 outblock.cmd_count = 0;
2170 outblock.authenticating = FALSE;
2172 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2173 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2174 ob->command_timeout);
2175 (void)close(inblock.sock);
2180 /*************************************************
2181 * Prepare addresses for delivery *
2182 *************************************************/
2184 /* This function is called to flush out error settings from previous delivery
2185 attempts to other hosts. It also records whether we got here via an MX record
2186 or not in the more_errno field of the address. We are interested only in
2187 addresses that are still marked DEFER - others may have got delivered to a
2188 previously considered IP address. Set their status to PENDING_DEFER to indicate
2189 which ones are relevant this time.
2192 addrlist the list of addresses
2193 host the host we are delivering to
2195 Returns: the first address for this delivery
2198 static address_item *
2199 prepare_addresses(address_item *addrlist, host_item *host)
2201 address_item *first_addr = NULL;
2203 for (addr = addrlist; addr != NULL; addr = addr->next)
2205 if (addr->transport_return != DEFER) continue;
2206 if (first_addr == NULL) first_addr = addr;
2207 addr->transport_return = PENDING_DEFER;
2208 addr->basic_errno = 0;
2209 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
2210 addr->message = NULL;
2212 addr->cipher = NULL;
2213 addr->peerdn = NULL;
2221 /*************************************************
2222 * Main entry point *
2223 *************************************************/
2225 /* See local README for interface details. As this is a remote transport, it is
2226 given a chain of addresses to be delivered in one connection, if possible. It
2227 always returns TRUE, indicating that each address has its own independent
2228 status set, except if there is a setting up problem, in which case it returns
2232 smtp_transport_entry(
2233 transport_instance *tblock, /* data for this instantiation */
2234 address_item *addrlist) /* addresses we are working on */
2238 int hosts_defer = 0;
2240 int hosts_looked_up = 0;
2241 int hosts_retry = 0;
2242 int hosts_serial = 0;
2243 int hosts_total = 0;
2244 int total_hosts_tried = 0;
2246 BOOL expired = TRUE;
2247 BOOL continuing = continue_hostname != NULL;
2248 uschar *expanded_hosts = NULL;
2250 uschar *tid = string_sprintf("%s transport", tblock->name);
2251 smtp_transport_options_block *ob =
2252 (smtp_transport_options_block *)(tblock->options_block);
2253 host_item *hostlist = addrlist->host_list;
2254 host_item *host = NULL;
2258 debug_printf("%s transport entered\n", tblock->name);
2259 for (addr = addrlist; addr != NULL; addr = addr->next)
2260 debug_printf(" %s\n", addr->address);
2261 if (continuing) debug_printf("already connected to %s [%s]\n",
2262 continue_hostname, continue_host_address);
2265 /* Set the flag requesting that these hosts be added to the waiting
2266 database if the delivery fails temporarily or if we are running with
2267 queue_smtp or a 2-stage queue run. This gets unset for certain
2268 kinds of error, typically those that are specific to the message. */
2270 update_waiting = TRUE;
2272 /* If a host list is not defined for the addresses - they must all have the
2273 same one in order to be passed to a single transport - or if the transport has
2274 a host list with hosts_override set, use the host list supplied with the
2275 transport. It is an error for this not to exist. */
2277 if (hostlist == NULL || (ob->hosts_override && ob->hosts != NULL))
2279 if (ob->hosts == NULL)
2281 addrlist->message = string_sprintf("%s transport called with no hosts set",
2283 addrlist->transport_return = PANIC;
2284 return FALSE; /* Only top address has status */
2287 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
2290 /* If the transport's host list contains no '$' characters, and we are not
2291 randomizing, it is fixed and therefore a chain of hosts can be built once
2292 and for all, and remembered for subsequent use by other calls to this
2293 transport. If, on the other hand, the host list does contain '$', or we are
2294 randomizing its order, we have to rebuild it each time. In the fixed case,
2295 as the hosts string will never be used again, it doesn't matter that we
2296 replace all the : characters with zeros. */
2298 if (ob->hostlist == NULL)
2300 uschar *s = ob->hosts;
2302 if (Ustrchr(s, '$') != NULL)
2304 expanded_hosts = expand_string(s);
2305 if (expanded_hosts == NULL)
2307 addrlist->message = string_sprintf("failed to expand list of hosts "
2308 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
2309 addrlist->transport_return = search_find_defer? DEFER : PANIC;
2310 return FALSE; /* Only top address has status */
2312 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
2313 "\"%s\"\n", s, expanded_hosts);
2317 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
2319 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
2321 /* Check that the expansion yielded something useful. */
2322 if (hostlist == NULL)
2325 string_sprintf("%s transport has empty hosts setting", tblock->name);
2326 addrlist->transport_return = PANIC;
2327 return FALSE; /* Only top address has status */
2330 /* If there was no expansion of hosts, save the host list for
2333 if (expanded_hosts == NULL) ob->hostlist = hostlist;
2336 /* This is not the first time this transport has been run in this delivery;
2337 the host list was built previously. */
2339 else hostlist = ob->hostlist;
2342 /* The host list was supplied with the address. If hosts_randomize is set, we
2343 must sort it into a random order if it did not come from MX records and has not
2344 already been randomized (but don't bother if continuing down an existing
2347 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continuing)
2349 host_item *newlist = NULL;
2350 while (hostlist != NULL)
2352 host_item *h = hostlist;
2353 hostlist = hostlist->next;
2355 h->sort_key = random_number(100);
2357 if (newlist == NULL)
2362 else if (h->sort_key < newlist->sort_key)
2369 host_item *hh = newlist;
2370 while (hh->next != NULL)
2372 if (h->sort_key < hh->next->sort_key) break;
2380 hostlist = addrlist->host_list = newlist;
2384 /* Sort out the default port. */
2386 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
2389 /* For each host-plus-IP-address on the list:
2391 . If this is a continued delivery and the host isn't the one with the
2392 current connection, skip.
2394 . If the status is unusable (i.e. previously failed or retry checked), skip.
2396 . If no IP address set, get the address, either by turning the name into
2397 an address, calling gethostbyname if gethostbyname is on, or by calling
2398 the DNS. The DNS may yield multiple addresses, in which case insert the
2399 extra ones into the list.
2401 . Get the retry data if not previously obtained for this address and set the
2402 field which remembers the state of this address. Skip if the retry time is
2403 not reached. If not, remember whether retry data was found. The retry string
2404 contains both the name and the IP address.
2406 . Scan the list of addresses and mark those whose status is DEFER as
2407 PENDING_DEFER. These are the only ones that will be processed in this cycle
2410 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
2411 Some addresses may be successfully delivered, others may fail, and yet
2412 others may get temporary errors and so get marked DEFER.
2414 . The return from the delivery attempt is OK if a connection was made and a
2415 valid SMTP dialogue was completed. Otherwise it is DEFER.
2417 . If OK, add a "remove" retry item for this host/IPaddress, if any.
2419 . If fail to connect, or other defer state, add a retry item.
2421 . If there are any addresses whose status is still DEFER, carry on to the
2422 next host/IPaddress, unless we have tried the number of hosts given
2423 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
2424 there is some fancy logic for hosts_max_try that means its limit can be
2425 overstepped in some circumstances.
2427 If we get to the end of the list, all hosts have deferred at least one address,
2428 or not reached their retry times. If delay_after_cutoff is unset, it requests a
2429 delivery attempt to those hosts whose last try was before the arrival time of
2430 the current message. To cope with this, we have to go round the loop a second
2431 time. After that, set the status and error data for any addresses that haven't
2432 had it set already. */
2434 for (cutoff_retry = 0; expired &&
2435 cutoff_retry < ((ob->delay_after_cutoff)? 1 : 2);
2438 host_item *nexthost = NULL;
2439 int unexpired_hosts_tried = 0;
2441 for (host = hostlist;
2443 unexpired_hosts_tried < ob->hosts_max_try &&
2444 total_hosts_tried < ob->hosts_max_try_hardlimit;
2450 BOOL serialized = FALSE;
2451 BOOL host_is_expired = FALSE;
2452 BOOL message_defer = FALSE;
2453 BOOL ifchanges = FALSE;
2454 BOOL some_deferred = FALSE;
2455 address_item *first_addr = NULL;
2456 uschar *interface = NULL;
2457 uschar *retry_host_key = NULL;
2458 uschar *retry_message_key = NULL;
2459 uschar *serialize_key = NULL;
2461 /* Default next host is next host. :-) But this can vary if the
2462 hosts_max_try limit is hit (see below). It may also be reset if a host
2463 address is looked up here (in case the host was multihomed). */
2465 nexthost = host->next;
2467 /* If the address hasn't yet been obtained from the host name, look it up
2468 now, unless the host is already marked as unusable. If it is marked as
2469 unusable, it means that the router was unable to find its IP address (in
2470 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
2471 the lookup failed last time. We don't get this far if *all* MX records
2472 point to non-existent hosts; that is treated as a hard error.
2474 We can just skip this host entirely. When the hosts came from the router,
2475 the address will timeout based on the other host(s); when the address is
2476 looked up below, there is an explicit retry record added.
2478 Note that we mustn't skip unusable hosts if the address is not unset; they
2479 may be needed as expired hosts on the 2nd time round the cutoff loop. */
2481 if (host->address == NULL)
2483 int new_port, flags;
2485 uschar *canonical_name;
2487 if (host->status >= hstatus_unusable)
2489 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
2494 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
2496 /* The host name is permitted to have an attached port. Find it, and
2497 strip it from the name. Just remember it for now. */
2499 new_port = host_item_get_port(host);
2501 /* Count hosts looked up */
2505 /* Find by name if so configured, or if it's an IP address. We don't
2506 just copy the IP address, because we need the test-for-local to happen. */
2508 flags = HOST_FIND_BY_A;
2509 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
2510 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
2512 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
2513 rc = host_find_byname(host, NULL, flags, &canonical_name, TRUE);
2515 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
2516 &canonical_name, NULL);
2518 /* Update the host (and any additional blocks, resulting from
2519 multihoming) with a host-specific port, if any. */
2521 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
2523 /* Failure to find the host at this time (usually DNS temporary failure)
2524 is really a kind of routing failure rather than a transport failure.
2525 Therefore we add a retry item of the routing kind, not to stop us trying
2526 to look this name up here again, but to ensure the address gets timed
2527 out if the failures go on long enough. A complete failure at this point
2528 commonly points to a configuration error, but the best action is still
2529 to carry on for the next host. */
2531 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
2533 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
2535 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
2536 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
2537 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
2538 host->status = hstatus_unusable;
2540 for (addr = addrlist; addr != NULL; addr = addr->next)
2542 if (addr->transport_return != DEFER) continue;
2543 addr->basic_errno = ERRNO_UNKNOWNHOST;
2545 string_sprintf("failed to lookup IP address for %s", host->name);
2550 /* If the host is actually the local host, we may have a problem, or
2551 there may be some cunning configuration going on. In the problem case,
2552 log things and give up. The default transport status is already DEFER. */
2554 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
2556 for (addr = addrlist; addr != NULL; addr = addr->next)
2558 addr->basic_errno = 0;
2559 addr->message = string_sprintf("%s transport found host %s to be "
2560 "local", tblock->name, host->name);
2564 } /* End of block for IP address lookup */
2566 /* If this is a continued delivery, we are interested only in the host
2567 which matches the name of the existing open channel. The check is put
2568 here after the local host lookup, in case the name gets expanded as a
2569 result of the lookup. Set expired FALSE, to save the outer loop executing
2572 if (continuing && (Ustrcmp(continue_hostname, host->name) != 0 ||
2573 Ustrcmp(continue_host_address, host->address) != 0))
2576 continue; /* With next host */
2579 /* Reset the default next host in case a multihomed host whose addresses
2580 are not looked up till just above added to the host list. */
2582 nexthost = host->next;
2584 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
2585 domain is in queue_smtp_domains, we don't actually want to attempt any
2586 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
2587 there is a lookup defer in queue_smtp_domains, proceed as if the domain
2588 were not in it. We don't want to hold up all SMTP deliveries! Except when
2589 doing a two-stage queue run, don't do this if forcing. */
2591 if ((!deliver_force || queue_2stage) && (queue_smtp ||
2592 match_isinlist(addrlist->domain, &queue_smtp_domains, 0,
2593 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
2596 for (addr = addrlist; addr != NULL; addr = addr->next)
2598 if (addr->transport_return != DEFER) continue;
2599 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
2601 continue; /* With next host */
2604 /* Count hosts being considered - purely for an intelligent comment
2605 if none are usable. */
2609 /* Set $host and $host address now in case they are needed for the
2610 interface expansion or the serialize_hosts check; they remain set if an
2611 actual delivery happens. */
2613 deliver_host = host->name;
2614 deliver_host_address = host->address;
2616 /* Set up a string for adding to the retry key if the port number is not
2617 the standard SMTP port. A host may have its own port setting that overrides
2620 pistring = string_sprintf(":%d", (host->port == PORT_NONE)?
2622 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
2624 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
2625 string changes upon expansion, we must add it to the key that is used for
2626 retries, because connections to the same host from a different interface
2627 should be treated separately. */
2629 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET : AF_INET6;
2630 if (!smtp_get_interface(ob->interface, host_af, addrlist, &ifchanges,
2633 if (ifchanges) pistring = string_sprintf("%s/%s", pistring, interface);
2635 /* The first time round the outer loop, check the status of the host by
2636 inspecting the retry data. The second time round, we are interested only
2637 in expired hosts that haven't been tried since this message arrived. */
2639 if (cutoff_retry == 0)
2641 /* Ensure the status of the address is set by checking retry data if
2642 necessary. There maybe host-specific retry data (applicable to all
2643 messages) and also data for retries of a specific message at this host.
2644 If either of these retry records are actually read, the keys used are
2645 returned to save recomputing them later. */
2647 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
2648 ob->retry_include_ip_address, &retry_host_key, &retry_message_key);
2650 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
2651 (host->address == NULL)? US"" : host->address, pistring,
2652 (host->status == hstatus_usable)? "usable" :
2653 (host->status == hstatus_unusable)? "unusable" :
2654 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
2656 /* Skip this address if not usable at this time, noting if it wasn't
2657 actually expired, both locally and in the address. */
2659 switch (host->status)
2661 case hstatus_unusable:
2663 setflag(addrlist, af_retry_skipped);
2666 case hstatus_unusable_expired:
2669 case hwhy_retry: hosts_retry++; break;
2670 case hwhy_failed: hosts_fail++; break;
2671 case hwhy_deferred: hosts_defer++; break;
2674 /* If there was a retry message key, implying that previously there
2675 was a message-specific defer, we don't want to update the list of
2676 messages waiting for these hosts. */
2678 if (retry_message_key != NULL) update_waiting = FALSE;
2679 continue; /* With the next host or IP address */
2683 /* Second time round the loop: if the address is set but expired, and
2684 the message is newer than the last try, let it through. */
2688 if (host->address == NULL ||
2689 host->status != hstatus_unusable_expired ||
2690 host->last_try > received_time)
2693 debug_printf("trying expired host %s [%s]%s\n",
2694 host->name, host->address, pistring);
2695 host_is_expired = TRUE;
2698 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
2699 it remains TRUE only if all hosts are expired and none are actually tried.
2704 /* If this host is listed as one to which access must be serialized,
2705 see if another Exim process has a connection to it, and if so, skip
2706 this host. If not, update the database to record our connection to it
2707 and remember this for later deletion. Do not do any of this if we are
2708 sending the message down a pre-existing connection. */
2711 verify_check_this_host(&(ob->serialize_hosts), NULL, host->name,
2712 host->address, NULL) == OK)
2714 serialize_key = string_sprintf("host-serialize-%s", host->name);
2715 if (!enq_start(serialize_key))
2718 debug_printf("skipping host %s because another Exim process "
2719 "is connected to it\n", host->name);
2726 /* OK, we have an IP address that is not waiting for its retry time to
2727 arrive (it might be expired) OR (second time round the loop) we have an
2728 expired host that hasn't been tried since the message arrived. Have a go
2729 at delivering the message to it. First prepare the addresses by flushing
2730 out the result of previous attempts, and finding the first address that
2731 is still to be delivered. */
2733 first_addr = prepare_addresses(addrlist, host);
2735 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
2736 message_id, host->name, host->address, addrlist->address,
2737 (addrlist->next == NULL)? "" : ", ...");
2739 set_process_info("delivering %s to %s [%s] (%s%s)",
2740 message_id, host->name, host->address, addrlist->address,
2741 (addrlist->next == NULL)? "" : ", ...");
2743 /* This is not for real; don't do the delivery. If there are
2744 any remaining hosts, list them. */
2749 set_errno(addrlist, 0, NULL, OK, FALSE);
2750 for (addr = addrlist; addr != NULL; addr = addr->next)
2752 addr->host_used = host;
2753 addr->special_action = '*';
2754 addr->message = US"delivery bypassed by -N option";
2758 debug_printf("*** delivery by %s transport bypassed by -N option\n"
2759 "*** host and remaining hosts:\n", tblock->name);
2760 for (host2 = host; host2 != NULL; host2 = host2->next)
2761 debug_printf(" %s [%s]\n", host2->name,
2762 (host2->address == NULL)? US"unset" : host2->address);
2767 /* This is for real. If the host is expired, we don't count it for
2768 hosts_max_retry. This ensures that all hosts must expire before an address
2769 is timed out, unless hosts_max_try_hardlimit (which protects against
2770 lunatic DNS configurations) is reached.
2772 If the host is not expired and we are about to hit the hosts_max_retry
2773 limit, check to see if there is a subsequent hosts with a different MX
2774 value. If so, make that the next host, and don't count this one. This is a
2775 heuristic to make sure that different MXs do get tried. With a normal kind
2776 of retry rule, they would get tried anyway when the earlier hosts were
2777 delayed, but if the domain has a "retry every time" type of rule - as is
2778 often used for the the very large ISPs, that won't happen. */
2782 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
2786 debug_printf("hosts_max_try limit reached with this host\n");
2787 for (h = host; h != NULL; h = h->next)
2788 if (h->mx != host->mx) break;
2792 unexpired_hosts_tried--;
2793 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
2794 "and will be tried\n");
2798 /* Attempt the delivery. */
2800 total_hosts_tried++;
2801 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
2802 expanded_hosts != NULL, &message_defer, FALSE);
2805 OK => connection made, each address contains its result;
2806 message_defer is set for message-specific defers (when all
2807 recipients are marked defer)
2808 DEFER => there was a non-message-specific delivery problem;
2809 ERROR => there was a problem setting up the arguments for a filter,
2810 or there was a problem with expanding added headers
2813 /* If the result is not OK, there was a non-message-specific problem.
2814 If the result is DEFER, we need to write to the logs saying what happened
2815 for this particular host, except in the case of authentication and TLS
2816 failures, where the log has already been written. If all hosts defer a
2817 general message is written at the end. */
2819 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL &&
2820 first_addr->basic_errno != ERRNO_TLSFAILURE)
2821 write_logs(first_addr, host);
2823 /* If STARTTLS was accepted, but there was a failure in setting up the
2824 TLS session (usually a certificate screwup), and the host is not in
2825 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
2826 TLS forcibly turned off. We have to start from scratch with a new SMTP
2827 connection. That's why the retry is done from here, not from within
2828 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
2829 session, so the in-clear transmission after those errors, if permitted,
2830 happens inside smtp_deliver().] */
2833 if (rc == DEFER && first_addr->basic_errno == ERRNO_TLSFAILURE &&
2834 ob->tls_tempfail_tryclear &&
2835 verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
2836 host->address, NULL) != OK)
2838 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
2839 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
2840 first_addr = prepare_addresses(addrlist, host);
2841 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
2842 expanded_hosts != NULL, &message_defer, TRUE);
2843 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
2844 write_logs(first_addr, host);
2849 /* Delivery attempt finished */
2851 rs = (rc == OK)? US"OK" : (rc == DEFER)? US"DEFER" : (rc == ERROR)?
2854 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
2855 message_id, host->name, host->address, addrlist->address,
2856 (addrlist->next == NULL)? "" : " (& others)", rs);
2858 /* Release serialization if set up */
2860 if (serialized) enq_end(serialize_key);
2862 /* If the result is DEFER, or if a host retry record is known to exist, we
2863 need to add an item to the retry chain for updating the retry database
2864 at the end of delivery. We only need to add the item to the top address,
2865 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
2866 for any other delivery attempts using the same address. (It is copied into
2867 the unusable tree at the outer level, so even if different address blocks
2868 contain the same address, it still won't get tried again.) */
2870 if (rc == DEFER || retry_host_key != NULL)
2872 int delete_flag = (rc != DEFER)? rf_delete : 0;
2873 if (retry_host_key == NULL)
2875 retry_host_key = ob->retry_include_ip_address?
2876 string_sprintf("T:%S:%s%s", host->name, host->address, pistring) :
2877 string_sprintf("T:%S%s", host->name, pistring);
2880 /* If a delivery of another message over an existing SMTP connection
2881 yields DEFER, we do NOT set up retry data for the host. This covers the
2882 case when there are delays in routing the addresses in the second message
2883 that are so long that the server times out. This is alleviated by not
2884 routing addresses that previously had routing defers when handling an
2885 existing connection, but even so, this case may occur (e.g. if a
2886 previously happily routed address starts giving routing defers). If the
2887 host is genuinely down, another non-continued message delivery will
2888 notice it soon enough. */
2890 if (delete_flag != 0 || !continuing)
2891 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
2893 /* We may have tried an expired host, if its retry time has come; ensure
2894 the status reflects the expiry for the benefit of any other addresses. */
2898 host->status = (host_is_expired)?
2899 hstatus_unusable_expired : hstatus_unusable;
2900 host->why = hwhy_deferred;
2904 /* If message_defer is set (host was OK, but every recipient got deferred
2905 because of some message-specific problem), or if that had happened
2906 previously so that a message retry key exists, add an appropriate item
2907 to the retry chain. Note that if there was a message defer but now there is
2908 a host defer, the message defer record gets deleted. That seems perfectly
2909 reasonable. Also, stop the message from being remembered as waiting
2910 for specific hosts. */
2912 if (message_defer || retry_message_key != NULL)
2914 int delete_flag = message_defer? 0 : rf_delete;
2915 if (retry_message_key == NULL)
2917 retry_message_key = ob->retry_include_ip_address?
2918 string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
2920 string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
2922 retry_add_item(addrlist, retry_message_key,
2923 rf_message | rf_host | delete_flag);
2924 update_waiting = FALSE;
2927 /* Any return other than DEFER (that is, OK or ERROR) means that the
2928 addresses have got their final statuses filled in for this host. In the OK
2929 case, see if any of them are deferred. */
2933 for (addr = addrlist; addr != NULL; addr = addr->next)
2935 if (addr->transport_return == DEFER)
2937 some_deferred = TRUE;
2943 /* If no addresses deferred or the result was ERROR, return. We do this for
2944 ERROR because a failing filter set-up or add_headers expansion is likely to
2945 fail for any host we try. */
2947 if (rc == ERROR || (rc == OK && !some_deferred))
2949 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
2950 return TRUE; /* Each address has its status */
2953 /* If the result was DEFER or some individual addresses deferred, let
2954 the loop run to try other hosts with the deferred addresses, except for the
2955 case when we were trying to deliver down an existing channel and failed.
2956 Don't try any other hosts in this case. */
2958 if (continuing) break;
2960 /* If the whole delivery, or some individual addresses, were deferred and
2961 there are more hosts that could be tried, do not count this host towards
2962 the hosts_max_try limit if the age of the message is greater than the
2963 maximum retry time for this host. This means we may try try all hosts,
2964 ignoring the limit, when messages have been around for some time. This is
2965 important because if we don't try all hosts, the address will never time
2966 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
2968 if ((rc == DEFER || some_deferred) && nexthost != NULL)
2971 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
2973 if (retry != NULL && retry->rules != NULL)
2975 retry_rule *last_rule;
2976 for (last_rule = retry->rules;
2977 last_rule->next != NULL;
2978 last_rule = last_rule->next);
2979 timedout = time(NULL) - received_time > last_rule->timeout;
2981 else timedout = TRUE; /* No rule => timed out */
2985 unexpired_hosts_tried--;
2986 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
2987 "hosts_max_try (message older than host's retry time)\n");
2990 } /* End of loop for trying multiple hosts. */
2992 /* This is the end of the loop that repeats iff expired is TRUE and
2993 ob->delay_after_cutoff is FALSE. The second time round we will
2994 try those hosts that haven't been tried since the message arrived. */
2998 debug_printf("all IP addresses skipped or deferred at least one address\n");
2999 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
3000 debug_printf("retrying IP addresses not tried since message arrived\n");
3005 /* Get here if all IP addresses are skipped or defer at least one address. In
3006 MUA wrapper mode, this will happen only for connection or other non-message-
3007 specific failures. Force the delivery status for all addresses to FAIL. */
3011 for (addr = addrlist; addr != NULL; addr = addr->next)
3012 addr->transport_return = FAIL;
3016 /* In the normal, non-wrapper case, add a standard message to each deferred
3017 address if there hasn't been an error, that is, if it hasn't actually been
3018 tried this time. The variable "expired" will be FALSE if any deliveries were
3019 actually tried, or if there was at least one host that was not expired. That
3020 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
3021 a delivery has been tried, an error code will be set, and the failing of the
3022 message is handled by the retry code later.
3024 If queue_smtp is set, or this transport was called to send a subsequent message
3025 down an existing TCP/IP connection, and something caused the host not to be
3026 found, we end up here, but can detect these cases and handle them specially. */
3028 for (addr = addrlist; addr != NULL; addr = addr->next)
3030 /* If host is not NULL, it means that we stopped processing the host list
3031 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
3032 means we need to behave as if some hosts were skipped because their retry
3033 time had not come. Specifically, this prevents the address from timing out.
3034 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
3035 hosts were tried. */
3039 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
3042 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
3043 "hosts were tried\n");
3048 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
3049 setflag(addr, af_retry_skipped);
3053 if (queue_smtp) /* no deliveries attempted */
3055 addr->transport_return = DEFER;
3056 addr->basic_errno = 0;
3057 addr->message = US"SMTP delivery explicitly queued";
3060 else if (addr->transport_return == DEFER &&
3061 (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0) &&
3062 addr->message == NULL)
3064 addr->basic_errno = ERRNO_HRETRY;
3065 if (continue_hostname != NULL)
3067 addr->message = US"no host found for existing SMTP connection";
3071 setflag(addr, af_pass_message); /* This is not a security risk */
3072 addr->message = (ob->delay_after_cutoff)?
3073 US"retry time not reached for any host after a long failure period" :
3074 US"all hosts have been failing for a long time and were last tried "
3075 "after this message arrived";
3077 /* If we are already using fallback hosts, or there are no fallback hosts
3078 defined, convert the result to FAIL to cause a bounce. */
3080 if (addr->host_list == addr->fallback_hosts ||
3081 addr->fallback_hosts == NULL)
3082 addr->transport_return = FAIL;
3086 if (hosts_retry == hosts_total)
3087 addr->message = US"retry time not reached for any host";
3088 else if (hosts_fail == hosts_total)
3089 addr->message = US"all host address lookups failed permanently";
3090 else if (hosts_defer == hosts_total)
3091 addr->message = US"all host address lookups failed temporarily";
3092 else if (hosts_serial == hosts_total)
3093 addr->message = US"connection limit reached for all hosts";
3094 else if (hosts_fail+hosts_defer == hosts_total)
3095 addr->message = US"all host address lookups failed";
3096 else addr->message = US"some host address lookups failed and retry time "
3097 "not reached for other hosts or connection limit reached";
3102 /* Update the database which keeps information about which messages are waiting
3103 for which hosts to become available. For some message-specific errors, the
3104 update_waiting flag is turned off because we don't want follow-on deliveries in
3107 if (update_waiting) transport_update_waiting(hostlist, tblock->name);
3111 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3113 return TRUE; /* Each address has its status */
3116 /* End of transport/smtp.c */