1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2009 */
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 { "fallback_hosts", opt_stringptr,
59 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
60 { "final_timeout", opt_time,
61 (void *)offsetof(smtp_transport_options_block, final_timeout) },
62 { "gethostbyname", opt_bool,
63 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
65 { "gnutls_require_kx", opt_stringptr,
66 (void *)offsetof(smtp_transport_options_block, gnutls_require_kx) },
67 { "gnutls_require_mac", opt_stringptr,
68 (void *)offsetof(smtp_transport_options_block, gnutls_require_mac) },
69 { "gnutls_require_protocols", opt_stringptr,
70 (void *)offsetof(smtp_transport_options_block, gnutls_require_proto) },
72 { "helo_data", opt_stringptr,
73 (void *)offsetof(smtp_transport_options_block, helo_data) },
74 { "hosts", opt_stringptr,
75 (void *)offsetof(smtp_transport_options_block, hosts) },
76 { "hosts_avoid_esmtp", opt_stringptr,
77 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
78 { "hosts_avoid_pipelining", opt_stringptr,
79 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
81 { "hosts_avoid_tls", opt_stringptr,
82 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
84 { "hosts_max_try", opt_int,
85 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
86 { "hosts_max_try_hardlimit", opt_int,
87 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
89 { "hosts_nopass_tls", opt_stringptr,
90 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
92 { "hosts_override", opt_bool,
93 (void *)offsetof(smtp_transport_options_block, hosts_override) },
94 { "hosts_randomize", opt_bool,
95 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
96 { "hosts_require_auth", opt_stringptr,
97 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
99 { "hosts_require_tls", opt_stringptr,
100 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
102 { "hosts_try_auth", opt_stringptr,
103 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
104 { "interface", opt_stringptr,
105 (void *)offsetof(smtp_transport_options_block, interface) },
106 { "keepalive", opt_bool,
107 (void *)offsetof(smtp_transport_options_block, keepalive) },
108 { "lmtp_ignore_quota", opt_bool,
109 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
110 { "max_rcpt", opt_int | opt_public,
111 (void *)offsetof(transport_instance, max_addresses) },
112 { "multi_domain", opt_bool | opt_public,
113 (void *)offsetof(transport_instance, multi_domain) },
114 { "port", opt_stringptr,
115 (void *)offsetof(smtp_transport_options_block, port) },
116 { "protocol", opt_stringptr,
117 (void *)offsetof(smtp_transport_options_block, protocol) },
118 { "retry_include_ip_address", opt_bool,
119 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
120 { "serialize_hosts", opt_stringptr,
121 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
122 { "size_addition", opt_int,
123 (void *)offsetof(smtp_transport_options_block, size_addition) }
125 ,{ "tls_certificate", opt_stringptr,
126 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
127 { "tls_crl", opt_stringptr,
128 (void *)offsetof(smtp_transport_options_block, tls_crl) },
129 { "tls_privatekey", opt_stringptr,
130 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
131 { "tls_require_ciphers", opt_stringptr,
132 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
133 { "tls_tempfail_tryclear", opt_bool,
134 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
135 { "tls_verify_certificates", opt_stringptr,
136 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) }
140 /* Size of the options list. An extern variable has to be used so that its
141 address can appear in the tables drtables.c. */
143 int smtp_transport_options_count =
144 sizeof(smtp_transport_options)/sizeof(optionlist);
146 /* Default private options block for the smtp transport. */
148 smtp_transport_options_block smtp_transport_option_defaults = {
150 NULL, /* fallback_hosts */
152 NULL, /* fallback_hostlist */
153 NULL, /* authenticated_sender */
154 US"$primary_hostname", /* helo_data */
155 NULL, /* interface */
157 US"smtp", /* protocol */
158 NULL, /* serialize_hosts */
159 NULL, /* hosts_try_auth */
160 NULL, /* hosts_require_auth */
161 NULL, /* hosts_require_tls */
162 NULL, /* hosts_avoid_tls */
163 NULL, /* hosts_avoid_pipelining */
164 NULL, /* hosts_avoid_esmtp */
165 NULL, /* hosts_nopass_tls */
166 5*60, /* command_timeout */
167 5*60, /* connect_timeout; shorter system default overrides */
168 5*60, /* data timeout */
169 10*60, /* final timeout */
170 1024, /* size_addition */
171 5, /* hosts_max_try */
172 50, /* hosts_max_try_hardlimit */
173 TRUE, /* address_retry_include_sender */
174 FALSE, /* allow_localhost */
175 FALSE, /* authenticated_sender_force */
176 FALSE, /* gethostbyname */
177 TRUE, /* dns_qualify_single */
178 FALSE, /* dns_search_parents */
179 TRUE, /* delay_after_cutoff */
180 FALSE, /* hosts_override */
181 FALSE, /* hosts_randomize */
182 TRUE, /* keepalive */
183 FALSE, /* lmtp_ignore_quota */
184 TRUE /* retry_include_ip_address */
186 ,NULL, /* tls_certificate */
188 NULL, /* tls_privatekey */
189 NULL, /* tls_require_ciphers */
190 NULL, /* gnutls_require_kx */
191 NULL, /* gnutls_require_mac */
192 NULL, /* gnutls_require_proto */
193 NULL, /* tls_verify_certificates */
194 TRUE /* tls_tempfail_tryclear */
197 ,NULL, /* dkim_canon */
198 NULL, /* dkim_domain */
199 NULL, /* dkim_private_key */
200 NULL, /* dkim_selector */
201 NULL, /* dkim_sign_headers */
202 NULL /* dkim_strict */
209 static uschar *smtp_command; /* Points to last cmd for error messages */
210 static uschar *mail_command; /* Points to MAIL cmd for error messages */
211 static BOOL update_waiting; /* TRUE to update the "wait" database */
214 /*************************************************
215 * Setup entry point *
216 *************************************************/
218 /* This function is called when the transport is about to be used,
219 but before running it in a sub-process. It is used for two things:
221 (1) To set the fallback host list in addresses, when delivering.
222 (2) To pass back the interface, port, protocol, and other options, for use
223 during callout verification.
226 tblock pointer to the transport instance block
227 addrlist list of addresses about to be transported
228 tf if not NULL, pointer to block in which to return options
229 uid the uid that will be set (not used)
230 gid the gid that will be set (not used)
231 errmsg place for error message (not used)
233 Returns: OK always (FAIL, DEFER not used)
237 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
238 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
240 smtp_transport_options_block *ob =
241 (smtp_transport_options_block *)(tblock->options_block);
243 errmsg = errmsg; /* Keep picky compilers happy */
247 /* Pass back options if required. This interface is getting very messy. */
251 tf->interface = ob->interface;
253 tf->protocol = ob->protocol;
254 tf->hosts = ob->hosts;
255 tf->hosts_override = ob->hosts_override;
256 tf->hosts_randomize = ob->hosts_randomize;
257 tf->gethostbyname = ob->gethostbyname;
258 tf->qualify_single = ob->dns_qualify_single;
259 tf->search_parents = ob->dns_search_parents;
260 tf->helo_data = ob->helo_data;
263 /* Set the fallback host list for all the addresses that don't have fallback
264 host lists, provided that the local host wasn't present in the original host
267 if (!testflag(addrlist, af_local_host_removed))
269 for (; addrlist != NULL; addrlist = addrlist->next)
270 if (addrlist->fallback_hosts == NULL)
271 addrlist->fallback_hosts = ob->fallback_hostlist;
279 /*************************************************
280 * Initialization entry point *
281 *************************************************/
283 /* Called for each instance, after its options have been read, to
284 enable consistency checks to be done, or anything else that needs
287 Argument: pointer to the transport instance block
292 smtp_transport_init(transport_instance *tblock)
294 smtp_transport_options_block *ob =
295 (smtp_transport_options_block *)(tblock->options_block);
297 /* Retry_use_local_part defaults FALSE if unset */
299 if (tblock->retry_use_local_part == TRUE_UNSET)
300 tblock->retry_use_local_part = FALSE;
302 /* Set the default port according to the protocol */
304 if (ob->port == NULL)
305 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
306 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
308 /* Set up the setup entry point, to be called before subprocesses for this
311 tblock->setup = smtp_transport_setup;
313 /* Complain if any of the timeouts are zero. */
315 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
316 ob->final_timeout <= 0)
317 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
318 "command, data, or final timeout value is zero for %s transport",
321 /* If hosts_override is set and there are local hosts, set the global
322 flag that stops verify from showing router hosts. */
324 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
326 /* If there are any fallback hosts listed, build a chain of host items
327 for them, but do not do any lookups at this time. */
329 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
336 /*************************************************
337 * Set delivery info into all active addresses *
338 *************************************************/
340 /* Only addresses whose status is >= PENDING are relevant. A lesser
341 status means that an address is not currently being processed.
344 addrlist points to a chain of addresses
345 errno_value to put in each address's errno field
346 msg to put in each address's message field
347 rc to put in each address's transport_return field
348 pass_message if TRUE, set the "pass message" flag in the address
350 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
351 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
352 this particular type of timeout.
358 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
363 if (errno_value == ERRNO_CONNECTTIMEOUT)
365 errno_value = ETIMEDOUT;
366 orvalue = RTEF_CTOUT;
368 for (addr = addrlist; addr != NULL; addr = addr->next)
370 if (addr->transport_return < PENDING) continue;
371 addr->basic_errno = errno_value;
372 addr->more_errno |= orvalue;
376 if (pass_message) setflag(addr, af_pass_message);
378 addr->transport_return = rc;
384 /*************************************************
385 * Check an SMTP response *
386 *************************************************/
388 /* This function is given an errno code and the SMTP response buffer
389 to analyse, together with the host identification for generating messages. It
390 sets an appropriate message and puts the first digit of the response code into
391 the yield variable. If no response was actually read, a suitable digit is
395 host the current host, to get its name for messages
396 errno_value pointer to the errno value
397 more_errno from the top address for use with ERRNO_FILTER_FAIL
398 buffer the SMTP response buffer
399 yield where to put a one-digit SMTP response code
400 message where to put an errror message
401 pass_message set TRUE if message is an SMTP response
403 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
406 static BOOL check_response(host_item *host, int *errno_value, int more_errno,
407 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
411 if (smtp_use_pipelining &&
412 (Ustrcmp(smtp_command, "MAIL") == 0 ||
413 Ustrcmp(smtp_command, "RCPT") == 0 ||
414 Ustrcmp(smtp_command, "DATA") == 0))
417 *yield = '4'; /* Default setting is to give a temporary error */
419 /* Handle response timeout */
421 if (*errno_value == ETIMEDOUT)
423 *message = US string_sprintf("SMTP timeout while connected to %s [%s] "
424 "after %s%s", host->name, host->address, pl, smtp_command);
425 if (transport_count > 0)
426 *message = US string_sprintf("%s (%d bytes written)", *message,
431 /* Handle malformed SMTP response */
433 if (*errno_value == ERRNO_SMTPFORMAT)
435 uschar *malfresp = string_printing(buffer);
436 while (isspace(*malfresp)) malfresp++;
438 *message = string_sprintf("Malformed SMTP reply (an empty line) from "
439 "%s [%s] in response to %s%s", host->name, host->address, pl,
442 *message = string_sprintf("Malformed SMTP reply from %s [%s] in response "
443 "to %s%s: %s", host->name, host->address, pl, smtp_command, malfresp);
447 /* Handle a failed filter process error; can't send QUIT as we mustn't
450 if (*errno_value == ERRNO_FILTER_FAIL)
452 *message = US string_sprintf("transport filter process failed (%d)%s",
454 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
458 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
461 if (*errno_value == ERRNO_CHHEADER_FAIL)
464 US string_sprintf("failed to expand headers_add or headers_remove: %s",
465 expand_string_message);
469 /* Handle failure to write a complete data block */
471 if (*errno_value == ERRNO_WRITEINCOMPLETE)
473 *message = US string_sprintf("failed to write a data block");
477 /* Handle error responses from the remote mailer. */
481 uschar *s = string_printing(buffer);
482 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
483 "host %s [%s]: %s", pl, smtp_command, host->name, host->address, s);
484 *pass_message = TRUE;
489 /* No data was read. If there is no errno, this must be the EOF (i.e.
490 connection closed) case, which causes deferral. An explicit connection reset
491 error has the same effect. Otherwise, put the host's identity in the message,
492 leaving the errno value to be interpreted as well. In all cases, we have to
493 assume the connection is now dead. */
495 if (*errno_value == 0 || *errno_value == ECONNRESET)
497 *errno_value = ERRNO_SMTPCLOSED;
498 *message = US string_sprintf("Remote host %s [%s] closed connection "
499 "in response to %s%s", host->name, host->address, pl, smtp_command);
501 else *message = US string_sprintf("%s [%s]", host->name, host->address);
508 /*************************************************
509 * Write error message to logs *
510 *************************************************/
512 /* This writes to the main log and to the message log.
515 addr the address item containing error information
516 host the current host
522 write_logs(address_item *addr, host_item *host)
524 if (addr->message != NULL)
526 uschar *message = addr->message;
527 if (addr->basic_errno > 0)
528 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
529 log_write(0, LOG_MAIN, "%s", message);
530 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
535 ((log_extra_selector & LX_outgoing_port) != 0)?
536 string_sprintf("%s [%s]:%d", host->name, host->address,
537 (host->port == PORT_NONE)? 25 : host->port)
539 string_sprintf("%s [%s]", host->name, host->address);
540 log_write(0, LOG_MAIN, "%s %s", msg, strerror(addr->basic_errno));
541 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), msg,
542 strerror(addr->basic_errno));
548 /*************************************************
549 * Synchronize SMTP responses *
550 *************************************************/
552 /* This function is called from smtp_deliver() to receive SMTP responses from
553 the server, and match them up with the commands to which they relate. When
554 PIPELINING is not in use, this function is called after every command, and is
555 therefore somewhat over-engineered, but it is simpler to use a single scheme
556 that works both with and without PIPELINING instead of having two separate sets
559 The set of commands that are buffered up with pipelining may start with MAIL
560 and may end with DATA; in between are RCPT commands that correspond to the
561 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
562 etc.) are never buffered.
564 Errors after MAIL or DATA abort the whole process leaving the response in the
565 buffer. After MAIL, pending responses are flushed, and the original command is
566 re-instated in big_buffer for error messages. For RCPT commands, the remote is
567 permitted to reject some recipient addresses while accepting others. However
568 certain errors clearly abort the whole process. Set the value in
569 transport_return to PENDING_OK if the address is accepted. If there is a
570 subsequent general error, it will get reset accordingly. If not, it will get
571 converted to OK at the end.
574 addrlist the complete address list
575 include_affixes TRUE if affixes include in RCPT
576 sync_addr ptr to the ptr of the one to start scanning at (updated)
577 host the host we are connected to
578 count the number of responses to read
580 include_sender true if 4xx retry is to include the sender it its key
581 pending_MAIL true if the first response is for MAIL
582 pending_DATA 0 if last command sent was not DATA
583 +1 if previously had a good recipient
584 -1 if not previously had a good recipient
585 inblock incoming SMTP block
586 timeout timeout value
587 buffer buffer for reading response
588 buffsize size of buffer
590 Returns: 3 if at least one address had 2xx and one had 5xx
591 2 if at least one address had 5xx but none had 2xx
592 1 if at least one host had a 2xx response, but none had 5xx
593 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
594 -1 timeout while reading RCPT response
595 -2 I/O or other non-response error for RCPT
596 -3 DATA or MAIL failed - errno and buffer set
600 sync_responses(address_item *addrlist, BOOL include_affixes,
601 address_item **sync_addr, host_item *host, int count,
602 BOOL address_retry_include_sender, BOOL pending_MAIL,
603 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
606 address_item *addr = *sync_addr;
609 /* Handle the response for a MAIL command. On error, reinstate the original
610 command in big_buffer for error message use, and flush any further pending
611 responses before returning, except after I/O errors and timeouts. */
616 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
618 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
619 if (errno == 0 && buffer[0] != 0)
621 uschar flushbuffer[4096];
623 if (buffer[0] == '4')
625 save_errno = ERRNO_MAIL4XX;
626 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
630 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
632 && (errno != 0 || flushbuffer[0] == 0))
641 if (pending_DATA) count--; /* Number of RCPT responses to come */
643 /* Read and handle the required number of RCPT responses, matching each one up
644 with an address by scanning for the next address whose status is PENDING_DEFER.
649 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
651 /* The address was accepted */
653 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
656 addr->transport_return = PENDING_OK;
658 /* If af_dr_retry_exists is set, there was a routing delay on this address;
659 ensure that any address-specific retry record is expunged. We do this both
660 for the basic key and for the version that also includes the sender. */
662 if (testflag(addr, af_dr_retry_exists))
664 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
666 retry_add_item(addr, altkey, rf_delete);
667 retry_add_item(addr, addr->address_retry_key, rf_delete);
671 /* Timeout while reading the response */
673 else if (errno == ETIMEDOUT)
675 int save_errno = errno;
676 uschar *message = string_sprintf("SMTP timeout while connected to %s [%s] "
677 "after RCPT TO:<%s>", host->name, host->address,
678 transport_rcpt_address(addr, include_affixes));
679 set_errno(addrlist, save_errno, message, DEFER, FALSE);
680 retry_add_item(addr, addr->address_retry_key, 0);
681 update_waiting = FALSE;
685 /* Handle other errors in obtaining an SMTP response by returning -1. This
686 will cause all the addresses to be deferred. Restore the SMTP command in
687 big_buffer for which we are checking the response, so the error message
690 else if (errno != 0 || buffer[0] == 0)
692 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
693 transport_rcpt_address(addr, include_affixes));
697 /* Handle SMTP permanent and temporary response codes. */
702 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
703 "host %s [%s]: %s", transport_rcpt_address(addr, include_affixes),
704 host->name, host->address, string_printing(buffer));
705 setflag(addr, af_pass_message);
706 deliver_msglog("%s %s\n", tod_stamp(tod_log), addr->message);
708 /* The response was 5xx */
710 if (buffer[0] == '5')
712 addr->transport_return = FAIL;
716 /* The response was 4xx */
720 addr->transport_return = DEFER;
721 addr->basic_errno = ERRNO_RCPT4XX;
722 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
724 /* Log temporary errors if there are more hosts to be tried. */
726 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", addr->message);
728 /* Do not put this message on the list of those waiting for specific
729 hosts, as otherwise it is likely to be tried too often. */
731 update_waiting = FALSE;
733 /* Add a retry item for the address so that it doesn't get tried again
734 too soon. If address_retry_include_sender is true, add the sender address
737 if (address_retry_include_sender)
739 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
741 retry_add_item(addr, altkey, 0);
743 else retry_add_item(addr, addr->address_retry_key, 0);
746 } /* Loop for next RCPT response */
748 /* Update where to start at for the next block of responses, unless we
749 have already handled all the addresses. */
751 if (addr != NULL) *sync_addr = addr->next;
753 /* Handle a response to DATA. If we have not had any good recipients, either
754 previously or in this block, the response is ignored. */
756 if (pending_DATA != 0 &&
757 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
762 if (pending_DATA > 0 || (yield & 1) != 0)
764 if (errno == 0 && buffer[0] == '4')
766 errno = ERRNO_DATA4XX;
767 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
771 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
772 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
773 "is in use and there were no good recipients\n", msg);
776 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
777 present) received 3xx. If any RCPTs were handled and yielded anything other
778 than 4xx, yield will be set non-zero. */
785 /*************************************************
786 * Deliver address list to given host *
787 *************************************************/
789 /* If continue_hostname is not null, we get here only when continuing to
790 deliver down an existing channel. The channel was passed as the standard
791 input. TLS is never active on a passed channel; the previous process always
792 closes it down before passing the connection on.
794 Otherwise, we have to make a connection to the remote host, and do the
795 initial protocol exchange.
797 When running as an MUA wrapper, if the sender or any recipient is rejected,
798 temporarily or permanently, we force failure for all recipients.
801 addrlist chain of potential addresses to deliver; only those whose
802 transport_return field is set to PENDING_DEFER are currently
803 being processed; others should be skipped - they have either
804 been delivered to an earlier host or IP address, or been
805 failed by one of them.
806 host host to deliver to
807 host_af AF_INET or AF_INET6
808 port default TCP/IP port to use, in host byte order
809 interface interface to bind to, or NULL
810 tblock transport instance block
811 copy_host TRUE if host set in addr->host_used must be copied, because
812 it is specific to this call of the transport
813 message_defer set TRUE if yield is OK, but all addresses were deferred
814 because of a non-recipient, non-host failure, that is, a
815 4xx response to MAIL FROM, DATA, or ".". This is a defer
816 that is specific to the message.
817 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
818 a second attempt after TLS initialization fails
820 Returns: OK - the connection was made and the delivery attempted;
821 the result for each address is in its data block.
822 DEFER - the connection could not be made, or something failed
823 while setting up the SMTP session, or there was a
824 non-message-specific error, such as a timeout.
825 ERROR - a filter command is specified for this transport,
826 and there was a problem setting it up; OR helo_data
827 or add_headers or authenticated_sender is specified
828 for this transport, and the string failed to expand
832 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
833 uschar *interface, transport_instance *tblock, BOOL copy_host,
834 BOOL *message_defer, BOOL suppress_tls)
837 address_item *sync_addr;
838 address_item *first_addr = addrlist;
843 time_t start_delivery_time = time(NULL);
844 smtp_transport_options_block *ob =
845 (smtp_transport_options_block *)(tblock->options_block);
846 BOOL lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
847 BOOL smtps = strcmpic(ob->protocol, US"smtps") == 0;
849 BOOL send_rset = TRUE;
850 BOOL send_quit = TRUE;
851 BOOL setting_up = TRUE;
852 BOOL completed_address = FALSE;
855 BOOL pass_message = FALSE;
856 smtp_inblock inblock;
857 smtp_outblock outblock;
858 int max_rcpt = tblock->max_addresses;
859 uschar *igquotstr = US"";
860 uschar *local_authenticated_sender = authenticated_sender;
861 uschar *helo_data = NULL;
862 uschar *message = NULL;
863 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
866 uschar inbuffer[4096];
867 uschar outbuffer[1024];
869 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
871 *message_defer = FALSE;
872 smtp_command = US"initial connection";
873 if (max_rcpt == 0) max_rcpt = 999999;
875 /* Set up the buffer for reading SMTP response packets. */
877 inblock.buffer = inbuffer;
878 inblock.buffersize = sizeof(inbuffer);
879 inblock.ptr = inbuffer;
880 inblock.ptrend = inbuffer;
882 /* Set up the buffer for holding SMTP commands while pipelining */
884 outblock.buffer = outbuffer;
885 outblock.buffersize = sizeof(outbuffer);
886 outblock.ptr = outbuffer;
887 outblock.cmd_count = 0;
888 outblock.authenticating = FALSE;
890 /* Reset the parameters of a TLS session. */
895 /* If an authenticated_sender override has been specified for this transport
896 instance, expand it. If the expansion is forced to fail, and there was already
897 an authenticated_sender for this message, the original value will be used.
898 Other expansion failures are serious. An empty result is ignored, but there is
899 otherwise no check - this feature is expected to be used with LMTP and other
900 cases where non-standard addresses (e.g. without domains) might be required. */
902 if (ob->authenticated_sender != NULL)
904 uschar *new = expand_string(ob->authenticated_sender);
907 if (!expand_string_forcedfail)
909 uschar *message = string_sprintf("failed to expand "
910 "authenticated_sender: %s", expand_string_message);
911 set_errno(addrlist, 0, message, DEFER, FALSE);
915 else if (new[0] != 0) local_authenticated_sender = new;
921 set_errno(addrlist, 0, US"TLS support not available", DEFER, FALSE);
926 /* Make a connection to the host if this isn't a continued delivery, and handle
927 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
928 specially so they can be identified for retries. */
930 if (continue_hostname == NULL)
932 inblock.sock = outblock.sock =
933 smtp_connect(host, host_af, port, interface, ob->connect_timeout,
934 ob->keepalive); /* This puts port into host->port */
936 if (inblock.sock < 0)
938 set_errno(addrlist, (errno == ETIMEDOUT)? ERRNO_CONNECTTIMEOUT : errno,
943 /* Expand the greeting message while waiting for the initial response. (Makes
944 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
945 delayed till here so that $sending_interface and $sending_port are set. */
947 helo_data = expand_string(ob->helo_data);
949 /* The first thing is to wait for an initial OK response. The dreaded "goto"
950 is nevertheless a reasonably clean way of programming this kind of logic,
951 where you want to escape on any error. */
955 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
956 ob->command_timeout)) goto RESPONSE_FAILED;
958 /* Now check if the helo_data expansion went well, and sign off cleanly if
961 if (helo_data == NULL)
963 uschar *message = string_sprintf("failed to expand helo_data: %s",
964 expand_string_message);
965 set_errno(addrlist, 0, message, DEFER, FALSE);
971 /** Debugging without sending a message
972 addrlist->transport_return = DEFER;
976 /* Errors that occur after this point follow an SMTP command, which is
977 left in big_buffer by smtp_write_command() for use in error messages. */
979 smtp_command = big_buffer;
981 /* Tell the remote who we are...
983 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
984 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
985 greeting is of this form. The assumption was that the far end supports it
986 properly... but experience shows that there are some that give 5xx responses,
987 even though the banner includes "ESMTP" (there's a bloody-minded one that
988 says "ESMTP not spoken here"). Cope with that case.
990 September 2000: Time has passed, and it seems reasonable now to always send
991 EHLO at the start. It is also convenient to make the change while installing
994 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
995 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
996 would be no way to send out the mails, so there is now a host list
997 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
998 PIPELINING problem as well. Maybe it can also be useful to cure other
999 problems with broken servers.
1001 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1002 Then somebody tried it with a Microsoft mailer... It seems that all other
1003 mailers use upper case for some reason (the RFC is quite clear about case
1004 independence) so, for peace of mind, I gave in. */
1006 esmtp = verify_check_this_host(&(ob->hosts_avoid_esmtp), NULL,
1007 host->name, host->address, NULL) != OK;
1009 /* Alas; be careful, since this goto is not an error-out, so conceivably
1010 we might set data between here and the target which we assume to exist
1011 and be usable. I can see this coming back to bite us. */
1016 suppress_tls = FALSE;
1017 ob->tls_tempfail_tryclear = FALSE;
1018 smtp_command = US"SSL-on-connect";
1025 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1026 lmtp? "LHLO" : "EHLO", helo_data) < 0)
1028 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1029 ob->command_timeout))
1031 if (errno != 0 || buffer[0] == 0 || lmtp) goto RESPONSE_FAILED;
1038 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1043 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1045 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1046 ob->command_timeout)) goto RESPONSE_FAILED;
1049 /* Set IGNOREQUOTA if the response to LHLO specifies support and the
1050 lmtp_ignore_quota option was set. */
1052 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1053 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1054 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1056 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1059 tls_offered = esmtp &&
1060 pcre_exec(regex_STARTTLS, NULL, CS buffer, Ustrlen(buffer), 0,
1061 PCRE_EOPT, NULL, 0) >= 0;
1065 /* For continuing deliveries down the same channel, the socket is the standard
1066 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1067 below). Set up the pointer to where subsequent commands will be left, for
1068 error messages. Note that smtp_use_size and smtp_use_pipelining will have been
1069 set from the command line if they were set in the process that passed the
1074 inblock.sock = outblock.sock = fileno(stdin);
1075 smtp_command = big_buffer;
1076 host->port = port; /* Record the port that was used */
1079 /* If TLS is available on this connection, whether continued or not, attempt to
1080 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1081 send another EHLO - the server may give a different answer in secure mode. We
1082 use a separate buffer for reading the response to STARTTLS so that if it is
1083 negative, the original EHLO data is available for subsequent analysis, should
1084 the client not be required to use TLS. If the response is bad, copy the buffer
1085 for error analysis. */
1088 if (tls_offered && !suppress_tls &&
1089 verify_check_this_host(&(ob->hosts_avoid_tls), NULL, host->name,
1090 host->address, NULL) != OK)
1092 uschar buffer2[4096];
1093 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1096 /* If there is an I/O error, transmission of this message is deferred. If
1097 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1098 false, we also defer. However, if there is a temporary rejection of STARTTLS
1099 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1100 STARTTLS, we carry on. This means we will try to send the message in clear,
1101 unless the host is in hosts_require_tls (tested below). */
1103 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1104 ob->command_timeout))
1106 if (errno != 0 || buffer2[0] == 0 ||
1107 (buffer2[0] == '4' && !ob->tls_tempfail_tryclear))
1109 Ustrncpy(buffer, buffer2, sizeof(buffer));
1110 goto RESPONSE_FAILED;
1114 /* STARTTLS accepted: try to negotiate a TLS session. */
1119 int rc = tls_client_start(inblock.sock,
1122 NULL, /* No DH param */
1123 ob->tls_certificate,
1125 ob->tls_verify_certificates,
1127 ob->tls_require_ciphers,
1128 ob->gnutls_require_mac,
1129 ob->gnutls_require_kx,
1130 ob->gnutls_require_proto,
1131 ob->command_timeout);
1133 /* TLS negotiation failed; give an error. From outside, this function may
1134 be called again to try in clear on a new connection, if the options permit
1135 it for this host. */
1139 save_errno = ERRNO_TLSFAILURE;
1140 message = US"failure while setting up TLS session";
1145 /* TLS session is set up */
1147 for (addr = addrlist; addr != NULL; addr = addr->next)
1149 if (addr->transport_return == PENDING_DEFER)
1151 addr->cipher = tls_cipher;
1152 addr->peerdn = tls_peerdn;
1158 /* if smtps, we'll have smtp_command set to something else; always safe to
1160 smtp_command = big_buffer;
1162 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1163 helo_data is null, we are dealing with a connection that was passed from
1164 another process, and so we won't have expanded helo_data above. We have to
1165 expand it here. $sending_ip_address and $sending_port are set up right at the
1166 start of the Exim process (in exim.c). */
1168 if (tls_active >= 0)
1171 if (helo_data == NULL)
1173 helo_data = expand_string(ob->helo_data);
1174 if (helo_data == NULL)
1176 uschar *message = string_sprintf("failed to expand helo_data: %s",
1177 expand_string_message);
1178 set_errno(addrlist, 0, message, DEFER, FALSE);
1184 /* For SMTPS we need to wait for the initial OK response. */
1187 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1188 ob->command_timeout)) goto RESPONSE_FAILED;
1192 greeting_cmd = "EHLO";
1195 greeting_cmd = "HELO";
1197 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1200 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1201 lmtp? "LHLO" : greeting_cmd, helo_data) < 0)
1203 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1204 ob->command_timeout))
1205 goto RESPONSE_FAILED;
1208 /* If the host is required to use a secure channel, ensure that we
1211 else if (verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
1212 host->address, NULL) == OK)
1214 save_errno = ERRNO_TLSREQUIRED;
1215 message = string_sprintf("a TLS session is required for %s [%s], but %s",
1216 host->name, host->address,
1217 tls_offered? "an attempt to start TLS failed" :
1218 "the server did not offer TLS support");
1223 /* If TLS is active, we have just started it up and re-done the EHLO command,
1224 so its response needs to be analyzed. If TLS is not active and this is a
1225 continued session down a previously-used socket, we haven't just done EHLO, so
1228 if (continue_hostname == NULL
1235 uschar *fail_reason = US"server did not advertise AUTH support";
1237 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
1238 lmtp_ignore_quota option was set. */
1240 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1241 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1242 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1244 /* If the response to EHLO specified support for the SIZE parameter, note
1245 this, provided size_addition is non-negative. */
1247 smtp_use_size = esmtp && ob->size_addition >= 0 &&
1248 pcre_exec(regex_SIZE, NULL, CS buffer, Ustrlen(CS buffer), 0,
1249 PCRE_EOPT, NULL, 0) >= 0;
1251 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
1252 the current host, esmtp will be false, so PIPELINING can never be used. If
1253 the current host matches hosts_avoid_pipelining, don't do it. */
1255 smtp_use_pipelining = esmtp &&
1256 verify_check_this_host(&(ob->hosts_avoid_pipelining), NULL, host->name,
1257 host->address, NULL) != OK &&
1258 pcre_exec(regex_PIPELINING, NULL, CS buffer, Ustrlen(CS buffer), 0,
1259 PCRE_EOPT, NULL, 0) >= 0;
1261 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
1262 smtp_use_pipelining? "" : "not ");
1264 /* Note if the response to EHLO specifies support for the AUTH extension.
1265 If it has, check that this host is one we want to authenticate to, and do
1266 the business. The host name and address must be available when the
1267 authenticator's client driver is running. */
1269 smtp_authenticated = FALSE;
1270 require_auth = verify_check_this_host(&(ob->hosts_require_auth), NULL,
1271 host->name, host->address, NULL);
1273 if (esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
1275 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
1276 expand_nmax = -1; /* reset */
1278 /* Must not do this check until after we have saved the result of the
1279 regex match above. */
1281 if (require_auth == OK ||
1282 verify_check_this_host(&(ob->hosts_try_auth), NULL, host->name,
1283 host->address, NULL) == OK)
1286 fail_reason = US"no common mechanisms were found";
1288 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1290 /* Scan the configured authenticators looking for one which is configured
1291 for use as a client, which is not suppressed by client_condition, and
1292 whose name matches an authentication mechanism supported by the server.
1293 If one is found, attempt to authenticate by calling its client function.
1296 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1300 (au->client_condition != NULL &&
1301 !expand_check_condition(au->client_condition, au->name,
1302 US"client authenticator")))
1304 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1306 (au->client)? "client_condition is false" :
1307 "not configured as a client");
1311 /* Loop to scan supported server mechanisms */
1316 int len = Ustrlen(au->public_name);
1317 while (isspace(*p)) p++;
1319 if (strncmpic(au->public_name, p, len) != 0 ||
1320 (p[len] != 0 && !isspace(p[len])))
1322 while (*p != 0 && !isspace(*p)) p++;
1326 /* Found data for a listed mechanism. Call its client entry. Set
1327 a flag in the outblock so that data is overwritten after sending so
1328 that reflections don't show it. */
1330 fail_reason = US"authentication attempt(s) failed";
1331 outblock.authenticating = TRUE;
1332 rc = (au->info->clientcode)(au, &inblock, &outblock,
1333 ob->command_timeout, buffer, sizeof(buffer));
1334 outblock.authenticating = FALSE;
1335 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1338 /* A temporary authentication failure must hold up delivery to
1339 this host. After a permanent authentication failure, we carry on
1340 to try other authentication methods. If all fail hard, try to
1341 deliver the message unauthenticated unless require_auth was set. */
1346 smtp_authenticated = TRUE; /* stops the outer loop */
1349 /* Failure after writing a command */
1354 /* Failure after reading a response */
1357 if (errno != 0 || buffer[0] != '5') goto RESPONSE_FAILED;
1358 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1359 au->name, host->name, host->address, buffer);
1362 /* Failure by some other means. In effect, the authenticator
1363 decided it wasn't prepared to handle this case. Typically this
1364 is the result of "fail" in an expansion string. Do we need to
1365 log anything here? Feb 2006: a message is now put in the buffer
1366 if logging is required. */
1370 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1371 "authentication H=%s [%s] %s", au->name, host->name,
1372 host->address, buffer);
1375 /* Internal problem, message in buffer. */
1379 set_errno(addrlist, 0, string_copy(buffer), DEFER, FALSE);
1383 break; /* If not authenticated, try next authenticator */
1384 } /* Loop for scanning supported server mechanisms */
1385 } /* Loop for further authenticators */
1389 /* If we haven't authenticated, but are required to, give up. */
1391 if (require_auth == OK && !smtp_authenticated)
1394 set_errno(addrlist, ERRNO_AUTHFAIL,
1395 string_sprintf("authentication required but %s", fail_reason), DEFER,
1401 /* The setting up of the SMTP call is now complete. Any subsequent errors are
1402 message-specific. */
1406 /* If there is a filter command specified for this transport, we can now
1407 set it up. This cannot be done until the identify of the host is known. */
1409 if (tblock->filter_command != NULL)
1413 sprintf(CS buffer, "%.50s transport", tblock->name);
1414 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
1415 TRUE, DEFER, addrlist, buffer, NULL);
1416 transport_filter_timeout = tblock->filter_timeout;
1418 /* On failure, copy the error to all addresses, abandon the SMTP call, and
1423 set_errno(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
1431 /* For messages that have more than the maximum number of envelope recipients,
1432 we want to send several transactions down the same SMTP connection. (See
1433 comments in deliver.c as to how this reconciles, heuristically, with
1434 remote_max_parallel.) This optimization was added to Exim after the following
1435 code was already working. The simplest way to put it in without disturbing the
1436 code was to use a goto to jump back to this point when there is another
1437 transaction to handle. */
1440 sync_addr = first_addr;
1444 completed_address = FALSE;
1447 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
1448 qualification, send it, adding something to the message size to allow for
1449 imprecision and things that get added en route. Exim keeps the number of lines
1450 in a message, so we can give an accurate value for the original message, but we
1451 need some additional to handle added headers. (Double "." characters don't get
1452 included in the count.) */
1459 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
1463 /* Add the authenticated sender address if present */
1465 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1466 local_authenticated_sender != NULL)
1468 string_format(p, sizeof(buffer) - (p-buffer), " AUTH=%s",
1469 auth_xtextencode(local_authenticated_sender,
1470 Ustrlen(local_authenticated_sender)));
1473 /* From here until we send the DATA command, we can make use of PIPELINING
1474 if the server host supports it. The code has to be able to check the responses
1475 at any point, for when the buffer fills up, so we write it totally generally.
1476 When PIPELINING is off, each command written reports that it has flushed the
1479 pending_MAIL = TRUE; /* The block starts with MAIL */
1481 rc = smtp_write_command(&outblock, smtp_use_pipelining,
1482 "MAIL FROM:<%s>%s\r\n", return_path, buffer);
1483 mail_command = string_copy(big_buffer); /* Save for later error message */
1487 case -1: /* Transmission error */
1490 case +1: /* Block was sent */
1491 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1492 ob->command_timeout))
1494 if (errno == 0 && buffer[0] == '4')
1496 errno = ERRNO_MAIL4XX;
1497 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1499 goto RESPONSE_FAILED;
1501 pending_MAIL = FALSE;
1505 /* Pass over all the relevant recipient addresses for this host, which are the
1506 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
1507 several before we have to read the responses for those seen so far. This
1508 checking is done by a subroutine because it also needs to be done at the end.
1509 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
1510 the next one if not all are sent.
1512 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
1513 last address because we want to abort if any recipients have any kind of
1514 problem, temporary or permanent. We know that all recipient addresses will have
1515 the PENDING_DEFER status, because only one attempt is ever made, and we know
1516 that max_rcpt will be large, so all addresses will be done at once. */
1518 for (addr = first_addr;
1519 address_count < max_rcpt && addr != NULL;
1525 if (addr->transport_return != PENDING_DEFER) continue;
1528 no_flush = smtp_use_pipelining && (!mua_wrapper || addr->next != NULL);
1530 /* Now send the RCPT command, and process outstanding responses when
1531 necessary. After a timeout on RCPT, we just end the function, leaving the
1532 yield as OK, because this error can often mean that there is a problem with
1533 just one address, so we don't want to delay the host. */
1535 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s\r\n",
1536 transport_rcpt_address(addr, tblock->rcpt_include_affixes), igquotstr);
1537 if (count < 0) goto SEND_FAILED;
1540 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
1541 &sync_addr, host, count, ob->address_retry_include_sender,
1542 pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
1545 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1546 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1549 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1550 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1551 case 0: /* No 2xx or 5xx, but no probs */
1554 case -1: goto END_OFF; /* Timeout on RCPT */
1555 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
1557 pending_MAIL = FALSE; /* Dealt with MAIL */
1559 } /* Loop for next address */
1561 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
1562 permanently or temporarily. We should have flushed and synced after the last
1567 address_item *badaddr;
1568 for (badaddr = first_addr; badaddr != NULL; badaddr = badaddr->next)
1570 if (badaddr->transport_return != PENDING_OK) break;
1572 if (badaddr != NULL)
1574 set_errno(addrlist, 0, badaddr->message, FAIL,
1575 testflag(badaddr, af_pass_message));
1580 /* If ok is TRUE, we know we have got at least one good recipient, and must now
1581 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
1582 have a good recipient buffered up if we are pipelining. We don't want to waste
1583 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
1584 are pipelining. The responses are all handled by sync_responses(). */
1586 if (ok || (smtp_use_pipelining && !mua_wrapper))
1588 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
1589 if (count < 0) goto SEND_FAILED;
1590 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
1591 host, count, ob->address_retry_include_sender, pending_MAIL,
1592 ok? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
1594 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1595 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1598 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1599 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1600 case 0: break; /* No 2xx or 5xx, but no probs */
1602 case -1: goto END_OFF; /* Timeout on RCPT */
1603 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
1607 /* Save the first address of the next batch. */
1611 /* If there were no good recipients (but otherwise there have been no
1612 problems), just set ok TRUE, since we have handled address-specific errors
1613 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
1614 for handling the SMTP dot-handling protocol, flagging to apply to headers as
1615 well as body. Set the appropriate timeout value to be used for each chunk.
1616 (Haven't been able to make it work using select() for writing yet.) */
1618 if (!ok) ok = TRUE; else
1620 sigalrm_seen = FALSE;
1621 transport_write_timeout = ob->data_timeout;
1622 smtp_command = US"sending data block"; /* For error messages */
1623 DEBUG(D_transport|D_v)
1624 debug_printf(" SMTP>> writing message and terminating \".\"\n");
1625 transport_count = 0;
1626 #ifndef DISABLE_DKIM
1627 ok = dkim_transport_write_message(addrlist, inblock.sock,
1628 topt_use_crlf | topt_end_dot | topt_escape_headers |
1629 (tblock->body_only? topt_no_headers : 0) |
1630 (tblock->headers_only? topt_no_body : 0) |
1631 (tblock->return_path_add? topt_add_return_path : 0) |
1632 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1633 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1634 0, /* No size limit */
1635 tblock->add_headers, tblock->remove_headers,
1636 US".", US"..", /* Escaping strings */
1637 tblock->rewrite_rules, tblock->rewrite_existflags,
1638 ob->dkim_private_key, ob->dkim_domain, ob->dkim_selector,
1639 ob->dkim_canon, ob->dkim_strict, ob->dkim_sign_headers
1642 ok = transport_write_message(addrlist, inblock.sock,
1643 topt_use_crlf | topt_end_dot | topt_escape_headers |
1644 (tblock->body_only? topt_no_headers : 0) |
1645 (tblock->headers_only? topt_no_body : 0) |
1646 (tblock->return_path_add? topt_add_return_path : 0) |
1647 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1648 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1649 0, /* No size limit */
1650 tblock->add_headers, tblock->remove_headers,
1651 US".", US"..", /* Escaping strings */
1652 tblock->rewrite_rules, tblock->rewrite_existflags);
1655 /* transport_write_message() uses write() because it is called from other
1656 places to write to non-sockets. This means that under some OS (e.g. Solaris)
1657 it can exit with "Broken pipe" as its error. This really means that the
1658 socket got closed at the far end. */
1660 transport_write_timeout = 0; /* for subsequent transports */
1662 /* Failure can either be some kind of I/O disaster (including timeout),
1663 or the failure of a transport filter or the expansion of added headers. */
1667 buffer[0] = 0; /* There hasn't been a response */
1668 goto RESPONSE_FAILED;
1671 /* We used to send the terminating "." explicitly here, but because of
1672 buffering effects at both ends of TCP/IP connections, you don't gain
1673 anything by keeping it separate, so it might as well go in the final
1674 data buffer for efficiency. This is now done by setting the topt_end_dot
1677 smtp_command = US"end of data";
1679 /* For SMTP, we now read a single response that applies to the whole message.
1680 If it is OK, then all the addresses have been delivered. */
1684 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1686 if (!ok && errno == 0 && buffer[0] == '4')
1688 errno = ERRNO_DATA4XX;
1689 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1693 /* For LMTP, we get back a response for every RCPT command that we sent;
1694 some may be accepted and some rejected. For those that get a response, their
1695 status is fixed; any that are accepted have been handed over, even if later
1696 responses crash - at least, that's how I read RFC 2033.
1698 If all went well, mark the recipient addresses as completed, record which
1699 host/IPaddress they were delivered to, and cut out RSET when sending another
1700 message down the same channel. Write the completed addresses to the journal
1701 now so that they are recorded in case there is a crash of hardware or
1702 software before the spool gets updated. Also record the final SMTP
1703 confirmation if needed (for SMTP only). */
1708 int delivery_time = (int)(time(NULL) - start_delivery_time);
1711 uschar *conf = NULL;
1714 /* Make a copy of the host if it is local to this invocation
1715 of the transport. */
1719 thost = store_get(sizeof(host_item));
1721 thost->name = string_copy(host->name);
1722 thost->address = string_copy(host->address);
1726 /* Set up confirmation if needed - applies only to SMTP */
1728 if ((log_extra_selector & LX_smtp_confirmation) != 0 && !lmtp)
1730 uschar *s = string_printing(buffer);
1731 conf = (s == buffer)? (uschar *)string_copy(s) : s;
1734 /* Process all transported addresses - for LMTP, read a status for
1737 for (addr = addrlist; addr != first_addr; addr = addr->next)
1739 if (addr->transport_return != PENDING_OK) continue;
1741 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
1742 remaining addresses. Otherwise, it's a return code for just the one
1743 address. For temporary errors, add a retry item for the address so that
1744 it doesn't get tried again too soon. */
1748 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1751 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
1752 addr->message = string_sprintf("LMTP error after %s: %s",
1753 big_buffer, string_printing(buffer));
1754 setflag(addr, af_pass_message); /* Allow message to go to user */
1755 if (buffer[0] == '5')
1756 addr->transport_return = FAIL;
1759 errno = ERRNO_DATA4XX;
1760 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1761 addr->transport_return = DEFER;
1762 retry_add_item(addr, addr->address_retry_key, 0);
1766 completed_address = TRUE; /* NOW we can set this flag */
1767 if ((log_extra_selector & LX_smtp_confirmation) != 0)
1769 uschar *s = string_printing(buffer);
1770 conf = (s == buffer)? (uschar *)string_copy(s) : s;
1774 /* SMTP, or success return from LMTP for this address. Pass back the
1775 actual host that was used. */
1777 addr->transport_return = OK;
1778 addr->more_errno = delivery_time;
1779 addr->host_used = thost;
1780 addr->special_action = flag;
1781 addr->message = conf;
1784 /* Update the journal. For homonymic addresses, use the base address plus
1785 the transport name. See lots of comments in deliver.c about the reasons
1786 for the complications when homonyms are involved. Just carry on after
1787 write error, as it may prove possible to update the spool file later. */
1789 if (testflag(addr, af_homonym))
1790 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
1792 sprintf(CS buffer, "%.500s\n", addr->unique);
1794 DEBUG(D_deliver) debug_printf("journalling %s", buffer);
1795 len = Ustrlen(CS buffer);
1796 if (write(journal_fd, buffer, len) != len)
1797 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
1798 "%s: %s", buffer, strerror(errno));
1801 /* Ensure the journal file is pushed out to disk. */
1803 if (EXIMfsync(journal_fd) < 0)
1804 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
1810 /* Handle general (not specific to one address) failures here. The value of ok
1811 is used to skip over this code on the falling through case. A timeout causes a
1812 deferral. Other errors may defer or fail according to the response code, and
1813 may set up a special errno value, e.g. after connection chopped, which is
1814 assumed if errno == 0 and there is no text in the buffer. If control reaches
1815 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
1816 the problem is not related to this specific message. */
1825 send_quit = check_response(host, &save_errno, addrlist->more_errno,
1826 buffer, &code, &message, &pass_message);
1832 message = US string_sprintf("send() to %s [%s] failed: %s",
1833 host->name, host->address, strerror(save_errno));
1837 /* This label is jumped to directly when a TLS negotiation has failed,
1838 or was not done for a host for which it is required. Values will be set
1839 in message and save_errno, and setting_up will always be true. Treat as
1840 a temporary error. */
1847 /* If the failure happened while setting up the call, see if the failure was
1848 a 5xx response (this will either be on connection, or following HELO - a 5xx
1849 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
1850 never going to accept them. For other errors during setting up (timeouts or
1851 whatever), defer all addresses, and yield DEFER, so that the host is not
1852 tried again for a while. */
1855 ok = FALSE; /* For when reached by GOTO */
1861 set_errno(addrlist, save_errno, message, FAIL, pass_message);
1865 set_errno(addrlist, save_errno, message, DEFER, pass_message);
1870 /* We want to handle timeouts after MAIL or "." and loss of connection after
1871 "." specially. They can indicate a problem with the sender address or with
1872 the contents of the message rather than a real error on the connection. These
1873 cases are treated in the same way as a 4xx response. This next bit of code
1874 does the classification. */
1885 message_error = TRUE;
1889 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
1890 Ustrncmp(smtp_command,"end ",4) == 0;
1893 case ERRNO_SMTPCLOSED:
1894 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
1898 message_error = FALSE;
1902 /* Handle the cases that are treated as message errors. These are:
1904 (a) negative response or timeout after MAIL
1905 (b) negative response after DATA
1906 (c) negative response or timeout or dropped connection after "."
1908 It won't be a negative response or timeout after RCPT, as that is dealt
1909 with separately above. The action in all cases is to set an appropriate
1910 error code for all the addresses, but to leave yield set to OK because the
1911 host itself has not failed. Of course, it might in practice have failed
1912 when we've had a timeout, but if so, we'll discover that at the next
1913 delivery attempt. For a temporary error, set the message_defer flag, and
1914 write to the logs for information if this is not the last host. The error
1915 for the last host will be logged as part of the address's log line. */
1919 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
1920 set_errno(addrlist, save_errno, message, (code == '5')? FAIL : DEFER,
1923 /* If there's an errno, the message contains just the identity of
1926 if (code != '5') /* Anything other than 5 is treated as temporary */
1929 message = US string_sprintf("%s: %s", message, strerror(save_errno));
1930 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
1931 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
1932 *message_defer = TRUE;
1936 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
1937 ".", or some other transportation error. We defer all addresses and yield
1938 DEFER, except for the case of failed add_headers expansion, or a transport
1939 filter failure, when the yield should be ERROR, to stop it trying other
1944 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
1945 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
1946 set_errno(addrlist, save_errno, message, DEFER, pass_message);
1952 /* If all has gone well, send_quit will be set TRUE, implying we can end the
1953 SMTP session tidily. However, if there were too many addresses to send in one
1954 message (indicated by first_addr being non-NULL) we want to carry on with the
1955 rest of them. Also, it is desirable to send more than one message down the SMTP
1956 connection if there are several waiting, provided we haven't already sent so
1957 many as to hit the configured limit. The function transport_check_waiting looks
1958 for a waiting message and returns its id. Then transport_pass_socket tries to
1959 set up a continued delivery by passing the socket on to another process. The
1960 variable send_rset is FALSE if a message has just been successfully transfered.
1962 If we are already sending down a continued channel, there may be further
1963 addresses not yet delivered that are aimed at the same host, but which have not
1964 been passed in this run of the transport. In this case, continue_more will be
1965 true, and all we should do is send RSET if necessary, and return, leaving the
1968 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
1969 do not want to continue with other messages down the same channel, because that
1970 can lead to looping between two or more messages, all with the same,
1971 temporarily failing address(es). [The retry information isn't updated yet, so
1972 new processes keep on trying.] We probably also don't want to try more of this
1973 message's addresses either.
1975 If we have started a TLS session, we have to end it before passing the
1976 connection to a new process. However, not all servers can handle this (Exim
1977 can), so we do not pass such a connection on if the host matches
1978 hosts_nopass_tls. */
1981 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
1982 "yield=%d first_address is %sNULL\n", ok, send_quit, send_rset,
1983 continue_more, yield, (first_addr == NULL)? "":"not ");
1985 if (completed_address && ok && send_quit)
1988 if (first_addr != NULL || continue_more ||
1991 verify_check_this_host(&(ob->hosts_nopass_tls), NULL, host->name,
1992 host->address, NULL) != OK)
1994 transport_check_waiting(tblock->name, host->name,
1995 tblock->connection_max_messages, new_message_id, &more)
2003 if (! (ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
2005 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
2006 host->address, strerror(save_errno));
2009 else if (! (ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2010 ob->command_timeout)))
2013 send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
2017 DEBUG(D_transport) debug_printf("%s\n", msg);
2022 /* Either RSET was not needed, or it succeeded */
2026 if (first_addr != NULL) /* More addresses still to be sent */
2027 { /* in this run of the transport */
2028 continue_sequence++; /* Causes * in logging */
2031 if (continue_more) return yield; /* More addresses for another run */
2033 /* Pass the socket to a new Exim process. Before doing so, we must shut
2034 down TLS. Not all MTAs allow for the continuation of the SMTP session
2035 when TLS is shut down. We test for this by sending a new EHLO. If we
2036 don't get a good response, we don't attempt to pass the socket on. */
2039 if (tls_active >= 0)
2045 ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
2046 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2047 ob->command_timeout);
2051 /* If the socket is successfully passed, we musn't send QUIT (or
2052 indeed anything!) from here. */
2054 if (ok && transport_pass_socket(tblock->name, host->name, host->address,
2055 new_message_id, inblock.sock))
2061 /* If RSET failed and there are addresses left, they get deferred. */
2063 else set_errno(first_addr, errno, msg, DEFER, FALSE);
2067 /* End off tidily with QUIT unless the connection has died or the socket has
2068 been passed to another process. There has been discussion on the net about what
2069 to do after sending QUIT. The wording of the RFC suggests that it is necessary
2070 to wait for a response, but on the other hand, there isn't anything one can do
2071 with an error response, other than log it. Exim used to do that. However,
2072 further discussion suggested that it is positively advantageous not to wait for
2073 the response, but to close the session immediately. This is supposed to move
2074 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
2075 load from the server. (Hosts that are both servers and clients may not see much
2076 difference, of course.) Further discussion indicated that this was safe to do
2077 on Unix systems which have decent implementations of TCP/IP that leave the
2078 connection around for a while (TIME_WAIT) after the application has gone away.
2079 This enables the response sent by the server to be properly ACKed rather than
2080 timed out, as can happen on broken TCP/IP implementations on other OS.
2082 This change is being made on 31-Jul-98. After over a year of trouble-free
2083 operation, the old commented-out code was removed on 17-Sep-99. */
2086 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2094 /* Close the socket, and return the appropriate value, first setting
2095 continue_transport and continue_hostname NULL to prevent any other addresses
2096 that may include the host from trying to re-use a continuation socket. This
2097 works because the NULL setting is passed back to the calling process, and
2098 remote_max_parallel is forced to 1 when delivering over an existing connection,
2100 If all went well and continue_more is set, we shouldn't actually get here if
2101 there are further addresses, as the return above will be taken. However,
2102 writing RSET might have failed, or there may be other addresses whose hosts are
2103 specified in the transports, and therefore not visible at top level, in which
2104 case continue_more won't get set. */
2106 (void)close(inblock.sock);
2107 continue_transport = NULL;
2108 continue_hostname = NULL;
2115 /*************************************************
2116 * Closedown entry point *
2117 *************************************************/
2119 /* This function is called when exim is passed an open smtp channel
2120 from another incarnation, but the message which it has been asked
2121 to deliver no longer exists. The channel is on stdin.
2123 We might do fancy things like looking for another message to send down
2124 the channel, but if the one we sought has gone, it has probably been
2125 delivered by some other process that itself will seek further messages,
2126 so just close down our connection.
2128 Argument: pointer to the transport instance block
2133 smtp_transport_closedown(transport_instance *tblock)
2135 smtp_transport_options_block *ob =
2136 (smtp_transport_options_block *)(tblock->options_block);
2137 smtp_inblock inblock;
2138 smtp_outblock outblock;
2140 uschar inbuffer[4096];
2141 uschar outbuffer[16];
2143 inblock.sock = fileno(stdin);
2144 inblock.buffer = inbuffer;
2145 inblock.buffersize = sizeof(inbuffer);
2146 inblock.ptr = inbuffer;
2147 inblock.ptrend = inbuffer;
2149 outblock.sock = inblock.sock;
2150 outblock.buffersize = sizeof(outbuffer);
2151 outblock.buffer = outbuffer;
2152 outblock.ptr = outbuffer;
2153 outblock.cmd_count = 0;
2154 outblock.authenticating = FALSE;
2156 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2157 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2158 ob->command_timeout);
2159 (void)close(inblock.sock);
2164 /*************************************************
2165 * Prepare addresses for delivery *
2166 *************************************************/
2168 /* This function is called to flush out error settings from previous delivery
2169 attempts to other hosts. It also records whether we got here via an MX record
2170 or not in the more_errno field of the address. We are interested only in
2171 addresses that are still marked DEFER - others may have got delivered to a
2172 previously considered IP address. Set their status to PENDING_DEFER to indicate
2173 which ones are relevant this time.
2176 addrlist the list of addresses
2177 host the host we are delivering to
2179 Returns: the first address for this delivery
2182 static address_item *
2183 prepare_addresses(address_item *addrlist, host_item *host)
2185 address_item *first_addr = NULL;
2187 for (addr = addrlist; addr != NULL; addr = addr->next)
2189 if (addr->transport_return != DEFER) continue;
2190 if (first_addr == NULL) first_addr = addr;
2191 addr->transport_return = PENDING_DEFER;
2192 addr->basic_errno = 0;
2193 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
2194 addr->message = NULL;
2196 addr->cipher = NULL;
2197 addr->peerdn = NULL;
2205 /*************************************************
2206 * Main entry point *
2207 *************************************************/
2209 /* See local README for interface details. As this is a remote transport, it is
2210 given a chain of addresses to be delivered in one connection, if possible. It
2211 always returns TRUE, indicating that each address has its own independent
2212 status set, except if there is a setting up problem, in which case it returns
2216 smtp_transport_entry(
2217 transport_instance *tblock, /* data for this instantiation */
2218 address_item *addrlist) /* addresses we are working on */
2222 int hosts_defer = 0;
2224 int hosts_looked_up = 0;
2225 int hosts_retry = 0;
2226 int hosts_serial = 0;
2227 int hosts_total = 0;
2228 int total_hosts_tried = 0;
2230 BOOL expired = TRUE;
2231 BOOL continuing = continue_hostname != NULL;
2232 uschar *expanded_hosts = NULL;
2234 uschar *tid = string_sprintf("%s transport", tblock->name);
2235 smtp_transport_options_block *ob =
2236 (smtp_transport_options_block *)(tblock->options_block);
2237 host_item *hostlist = addrlist->host_list;
2238 host_item *host = NULL;
2242 debug_printf("%s transport entered\n", tblock->name);
2243 for (addr = addrlist; addr != NULL; addr = addr->next)
2244 debug_printf(" %s\n", addr->address);
2245 if (continuing) debug_printf("already connected to %s [%s]\n",
2246 continue_hostname, continue_host_address);
2249 /* Set the flag requesting that these hosts be added to the waiting
2250 database if the delivery fails temporarily or if we are running with
2251 queue_smtp or a 2-stage queue run. This gets unset for certain
2252 kinds of error, typically those that are specific to the message. */
2254 update_waiting = TRUE;
2256 /* If a host list is not defined for the addresses - they must all have the
2257 same one in order to be passed to a single transport - or if the transport has
2258 a host list with hosts_override set, use the host list supplied with the
2259 transport. It is an error for this not to exist. */
2261 if (hostlist == NULL || (ob->hosts_override && ob->hosts != NULL))
2263 if (ob->hosts == NULL)
2265 addrlist->message = string_sprintf("%s transport called with no hosts set",
2267 addrlist->transport_return = PANIC;
2268 return FALSE; /* Only top address has status */
2271 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
2274 /* If the transport's host list contains no '$' characters, and we are not
2275 randomizing, it is fixed and therefore a chain of hosts can be built once
2276 and for all, and remembered for subsequent use by other calls to this
2277 transport. If, on the other hand, the host list does contain '$', or we are
2278 randomizing its order, we have to rebuild it each time. In the fixed case,
2279 as the hosts string will never be used again, it doesn't matter that we
2280 replace all the : characters with zeros. */
2282 if (ob->hostlist == NULL)
2284 uschar *s = ob->hosts;
2286 if (Ustrchr(s, '$') != NULL)
2288 expanded_hosts = expand_string(s);
2289 if (expanded_hosts == NULL)
2291 addrlist->message = string_sprintf("failed to expand list of hosts "
2292 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
2293 addrlist->transport_return = search_find_defer? DEFER : PANIC;
2294 return FALSE; /* Only top address has status */
2296 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
2297 "\"%s\"\n", s, expanded_hosts);
2301 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
2303 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
2305 /* Check that the expansion yielded something useful. */
2306 if (hostlist == NULL)
2309 string_sprintf("%s transport has empty hosts setting", tblock->name);
2310 addrlist->transport_return = PANIC;
2311 return FALSE; /* Only top address has status */
2314 /* If there was no expansion of hosts, save the host list for
2317 if (expanded_hosts == NULL) ob->hostlist = hostlist;
2320 /* This is not the first time this transport has been run in this delivery;
2321 the host list was built previously. */
2323 else hostlist = ob->hostlist;
2326 /* The host list was supplied with the address. If hosts_randomize is set, we
2327 must sort it into a random order if it did not come from MX records and has not
2328 already been randomized (but don't bother if continuing down an existing
2331 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continuing)
2333 host_item *newlist = NULL;
2334 while (hostlist != NULL)
2336 host_item *h = hostlist;
2337 hostlist = hostlist->next;
2339 h->sort_key = random_number(100);
2341 if (newlist == NULL)
2346 else if (h->sort_key < newlist->sort_key)
2353 host_item *hh = newlist;
2354 while (hh->next != NULL)
2356 if (h->sort_key < hh->next->sort_key) break;
2364 hostlist = addrlist->host_list = newlist;
2368 /* Sort out the default port. */
2370 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
2373 /* For each host-plus-IP-address on the list:
2375 . If this is a continued delivery and the host isn't the one with the
2376 current connection, skip.
2378 . If the status is unusable (i.e. previously failed or retry checked), skip.
2380 . If no IP address set, get the address, either by turning the name into
2381 an address, calling gethostbyname if gethostbyname is on, or by calling
2382 the DNS. The DNS may yield multiple addresses, in which case insert the
2383 extra ones into the list.
2385 . Get the retry data if not previously obtained for this address and set the
2386 field which remembers the state of this address. Skip if the retry time is
2387 not reached. If not, remember whether retry data was found. The retry string
2388 contains both the name and the IP address.
2390 . Scan the list of addresses and mark those whose status is DEFER as
2391 PENDING_DEFER. These are the only ones that will be processed in this cycle
2394 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
2395 Some addresses may be successfully delivered, others may fail, and yet
2396 others may get temporary errors and so get marked DEFER.
2398 . The return from the delivery attempt is OK if a connection was made and a
2399 valid SMTP dialogue was completed. Otherwise it is DEFER.
2401 . If OK, add a "remove" retry item for this host/IPaddress, if any.
2403 . If fail to connect, or other defer state, add a retry item.
2405 . If there are any addresses whose status is still DEFER, carry on to the
2406 next host/IPaddress, unless we have tried the number of hosts given
2407 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
2408 there is some fancy logic for hosts_max_try that means its limit can be
2409 overstepped in some circumstances.
2411 If we get to the end of the list, all hosts have deferred at least one address,
2412 or not reached their retry times. If delay_after_cutoff is unset, it requests a
2413 delivery attempt to those hosts whose last try was before the arrival time of
2414 the current message. To cope with this, we have to go round the loop a second
2415 time. After that, set the status and error data for any addresses that haven't
2416 had it set already. */
2418 for (cutoff_retry = 0; expired &&
2419 cutoff_retry < ((ob->delay_after_cutoff)? 1 : 2);
2422 host_item *nexthost = NULL;
2423 int unexpired_hosts_tried = 0;
2425 for (host = hostlist;
2427 unexpired_hosts_tried < ob->hosts_max_try &&
2428 total_hosts_tried < ob->hosts_max_try_hardlimit;
2434 BOOL serialized = FALSE;
2435 BOOL host_is_expired = FALSE;
2436 BOOL message_defer = FALSE;
2437 BOOL ifchanges = FALSE;
2438 BOOL some_deferred = FALSE;
2439 address_item *first_addr = NULL;
2440 uschar *interface = NULL;
2441 uschar *retry_host_key = NULL;
2442 uschar *retry_message_key = NULL;
2443 uschar *serialize_key = NULL;
2445 /* Default next host is next host. :-) But this can vary if the
2446 hosts_max_try limit is hit (see below). It may also be reset if a host
2447 address is looked up here (in case the host was multihomed). */
2449 nexthost = host->next;
2451 /* If the address hasn't yet been obtained from the host name, look it up
2452 now, unless the host is already marked as unusable. If it is marked as
2453 unusable, it means that the router was unable to find its IP address (in
2454 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
2455 the lookup failed last time. We don't get this far if *all* MX records
2456 point to non-existent hosts; that is treated as a hard error.
2458 We can just skip this host entirely. When the hosts came from the router,
2459 the address will timeout based on the other host(s); when the address is
2460 looked up below, there is an explicit retry record added.
2462 Note that we mustn't skip unusable hosts if the address is not unset; they
2463 may be needed as expired hosts on the 2nd time round the cutoff loop. */
2465 if (host->address == NULL)
2467 int new_port, flags;
2469 uschar *canonical_name;
2471 if (host->status >= hstatus_unusable)
2473 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
2478 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
2480 /* The host name is permitted to have an attached port. Find it, and
2481 strip it from the name. Just remember it for now. */
2483 new_port = host_item_get_port(host);
2485 /* Count hosts looked up */
2489 /* Find by name if so configured, or if it's an IP address. We don't
2490 just copy the IP address, because we need the test-for-local to happen. */
2492 flags = HOST_FIND_BY_A;
2493 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
2494 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
2496 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
2497 rc = host_find_byname(host, NULL, flags, &canonical_name, TRUE);
2499 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
2500 &canonical_name, NULL);
2502 /* Update the host (and any additional blocks, resulting from
2503 multihoming) with a host-specific port, if any. */
2505 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
2507 /* Failure to find the host at this time (usually DNS temporary failure)
2508 is really a kind of routing failure rather than a transport failure.
2509 Therefore we add a retry item of the routing kind, not to stop us trying
2510 to look this name up here again, but to ensure the address gets timed
2511 out if the failures go on long enough. A complete failure at this point
2512 commonly points to a configuration error, but the best action is still
2513 to carry on for the next host. */
2515 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
2517 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
2519 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
2520 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
2521 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
2522 host->status = hstatus_unusable;
2524 for (addr = addrlist; addr != NULL; addr = addr->next)
2526 if (addr->transport_return != DEFER) continue;
2527 addr->basic_errno = ERRNO_UNKNOWNHOST;
2529 string_sprintf("failed to lookup IP address for %s", host->name);
2534 /* If the host is actually the local host, we may have a problem, or
2535 there may be some cunning configuration going on. In the problem case,
2536 log things and give up. The default transport status is already DEFER. */
2538 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
2540 for (addr = addrlist; addr != NULL; addr = addr->next)
2542 addr->basic_errno = 0;
2543 addr->message = string_sprintf("%s transport found host %s to be "
2544 "local", tblock->name, host->name);
2548 } /* End of block for IP address lookup */
2550 /* If this is a continued delivery, we are interested only in the host
2551 which matches the name of the existing open channel. The check is put
2552 here after the local host lookup, in case the name gets expanded as a
2553 result of the lookup. Set expired FALSE, to save the outer loop executing
2556 if (continuing && (Ustrcmp(continue_hostname, host->name) != 0 ||
2557 Ustrcmp(continue_host_address, host->address) != 0))
2560 continue; /* With next host */
2563 /* Reset the default next host in case a multihomed host whose addresses
2564 are not looked up till just above added to the host list. */
2566 nexthost = host->next;
2568 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
2569 domain is in queue_smtp_domains, we don't actually want to attempt any
2570 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
2571 there is a lookup defer in queue_smtp_domains, proceed as if the domain
2572 were not in it. We don't want to hold up all SMTP deliveries! Except when
2573 doing a two-stage queue run, don't do this if forcing. */
2575 if ((!deliver_force || queue_2stage) && (queue_smtp ||
2576 match_isinlist(addrlist->domain, &queue_smtp_domains, 0,
2577 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
2580 for (addr = addrlist; addr != NULL; addr = addr->next)
2582 if (addr->transport_return != DEFER) continue;
2583 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
2585 continue; /* With next host */
2588 /* Count hosts being considered - purely for an intelligent comment
2589 if none are usable. */
2593 /* Set $host and $host address now in case they are needed for the
2594 interface expansion or the serialize_hosts check; they remain set if an
2595 actual delivery happens. */
2597 deliver_host = host->name;
2598 deliver_host_address = host->address;
2600 /* Set up a string for adding to the retry key if the port number is not
2601 the standard SMTP port. A host may have its own port setting that overrides
2604 pistring = string_sprintf(":%d", (host->port == PORT_NONE)?
2606 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
2608 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
2609 string changes upon expansion, we must add it to the key that is used for
2610 retries, because connections to the same host from a different interface
2611 should be treated separately. */
2613 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET : AF_INET6;
2614 if (!smtp_get_interface(ob->interface, host_af, addrlist, &ifchanges,
2617 if (ifchanges) pistring = string_sprintf("%s/%s", pistring, interface);
2619 /* The first time round the outer loop, check the status of the host by
2620 inspecting the retry data. The second time round, we are interested only
2621 in expired hosts that haven't been tried since this message arrived. */
2623 if (cutoff_retry == 0)
2625 /* Ensure the status of the address is set by checking retry data if
2626 necessary. There maybe host-specific retry data (applicable to all
2627 messages) and also data for retries of a specific message at this host.
2628 If either of these retry records are actually read, the keys used are
2629 returned to save recomputing them later. */
2631 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
2632 ob->retry_include_ip_address, &retry_host_key, &retry_message_key);
2634 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
2635 (host->address == NULL)? US"" : host->address, pistring,
2636 (host->status == hstatus_usable)? "usable" :
2637 (host->status == hstatus_unusable)? "unusable" :
2638 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
2640 /* Skip this address if not usable at this time, noting if it wasn't
2641 actually expired, both locally and in the address. */
2643 switch (host->status)
2645 case hstatus_unusable:
2647 setflag(addrlist, af_retry_skipped);
2650 case hstatus_unusable_expired:
2653 case hwhy_retry: hosts_retry++; break;
2654 case hwhy_failed: hosts_fail++; break;
2655 case hwhy_deferred: hosts_defer++; break;
2658 /* If there was a retry message key, implying that previously there
2659 was a message-specific defer, we don't want to update the list of
2660 messages waiting for these hosts. */
2662 if (retry_message_key != NULL) update_waiting = FALSE;
2663 continue; /* With the next host or IP address */
2667 /* Second time round the loop: if the address is set but expired, and
2668 the message is newer than the last try, let it through. */
2672 if (host->address == NULL ||
2673 host->status != hstatus_unusable_expired ||
2674 host->last_try > received_time)
2677 debug_printf("trying expired host %s [%s]%s\n",
2678 host->name, host->address, pistring);
2679 host_is_expired = TRUE;
2682 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
2683 it remains TRUE only if all hosts are expired and none are actually tried.
2688 /* If this host is listed as one to which access must be serialized,
2689 see if another Exim process has a connection to it, and if so, skip
2690 this host. If not, update the database to record our connection to it
2691 and remember this for later deletion. Do not do any of this if we are
2692 sending the message down a pre-existing connection. */
2695 verify_check_this_host(&(ob->serialize_hosts), NULL, host->name,
2696 host->address, NULL) == OK)
2698 serialize_key = string_sprintf("host-serialize-%s", host->name);
2699 if (!enq_start(serialize_key))
2702 debug_printf("skipping host %s because another Exim process "
2703 "is connected to it\n", host->name);
2710 /* OK, we have an IP address that is not waiting for its retry time to
2711 arrive (it might be expired) OR (second time round the loop) we have an
2712 expired host that hasn't been tried since the message arrived. Have a go
2713 at delivering the message to it. First prepare the addresses by flushing
2714 out the result of previous attempts, and finding the first address that
2715 is still to be delivered. */
2717 first_addr = prepare_addresses(addrlist, host);
2719 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
2720 message_id, host->name, host->address, addrlist->address,
2721 (addrlist->next == NULL)? "" : ", ...");
2723 set_process_info("delivering %s to %s [%s] (%s%s)",
2724 message_id, host->name, host->address, addrlist->address,
2725 (addrlist->next == NULL)? "" : ", ...");
2727 /* This is not for real; don't do the delivery. If there are
2728 any remaining hosts, list them. */
2733 set_errno(addrlist, 0, NULL, OK, FALSE);
2734 for (addr = addrlist; addr != NULL; addr = addr->next)
2736 addr->host_used = host;
2737 addr->special_action = '*';
2738 addr->message = US"delivery bypassed by -N option";
2742 debug_printf("*** delivery by %s transport bypassed by -N option\n"
2743 "*** host and remaining hosts:\n", tblock->name);
2744 for (host2 = host; host2 != NULL; host2 = host2->next)
2745 debug_printf(" %s [%s]\n", host2->name,
2746 (host2->address == NULL)? US"unset" : host2->address);
2751 /* This is for real. If the host is expired, we don't count it for
2752 hosts_max_retry. This ensures that all hosts must expire before an address
2753 is timed out, unless hosts_max_try_hardlimit (which protects against
2754 lunatic DNS configurations) is reached.
2756 If the host is not expired and we are about to hit the hosts_max_retry
2757 limit, check to see if there is a subsequent hosts with a different MX
2758 value. If so, make that the next host, and don't count this one. This is a
2759 heuristic to make sure that different MXs do get tried. With a normal kind
2760 of retry rule, they would get tried anyway when the earlier hosts were
2761 delayed, but if the domain has a "retry every time" type of rule - as is
2762 often used for the the very large ISPs, that won't happen. */
2766 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
2770 debug_printf("hosts_max_try limit reached with this host\n");
2771 for (h = host; h != NULL; h = h->next)
2772 if (h->mx != host->mx) break;
2776 unexpired_hosts_tried--;
2777 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
2778 "and will be tried\n");
2782 /* Attempt the delivery. */
2784 total_hosts_tried++;
2785 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
2786 expanded_hosts != NULL, &message_defer, FALSE);
2789 OK => connection made, each address contains its result;
2790 message_defer is set for message-specific defers (when all
2791 recipients are marked defer)
2792 DEFER => there was a non-message-specific delivery problem;
2793 ERROR => there was a problem setting up the arguments for a filter,
2794 or there was a problem with expanding added headers
2797 /* If the result is not OK, there was a non-message-specific problem.
2798 If the result is DEFER, we need to write to the logs saying what happened
2799 for this particular host, except in the case of authentication and TLS
2800 failures, where the log has already been written. If all hosts defer a
2801 general message is written at the end. */
2803 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL &&
2804 first_addr->basic_errno != ERRNO_TLSFAILURE)
2805 write_logs(first_addr, host);
2807 /* If STARTTLS was accepted, but there was a failure in setting up the
2808 TLS session (usually a certificate screwup), and the host is not in
2809 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
2810 TLS forcibly turned off. We have to start from scratch with a new SMTP
2811 connection. That's why the retry is done from here, not from within
2812 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
2813 session, so the in-clear transmission after those errors, if permitted,
2814 happens inside smtp_deliver().] */
2817 if (rc == DEFER && first_addr->basic_errno == ERRNO_TLSFAILURE &&
2818 ob->tls_tempfail_tryclear &&
2819 verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
2820 host->address, NULL) != OK)
2822 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
2823 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
2824 first_addr = prepare_addresses(addrlist, host);
2825 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
2826 expanded_hosts != NULL, &message_defer, TRUE);
2827 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
2828 write_logs(first_addr, host);
2833 /* Delivery attempt finished */
2835 rs = (rc == OK)? US"OK" : (rc == DEFER)? US"DEFER" : (rc == ERROR)?
2838 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
2839 message_id, host->name, host->address, addrlist->address,
2840 (addrlist->next == NULL)? "" : " (& others)", rs);
2842 /* Release serialization if set up */
2844 if (serialized) enq_end(serialize_key);
2846 /* If the result is DEFER, or if a host retry record is known to exist, we
2847 need to add an item to the retry chain for updating the retry database
2848 at the end of delivery. We only need to add the item to the top address,
2849 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
2850 for any other delivery attempts using the same address. (It is copied into
2851 the unusable tree at the outer level, so even if different address blocks
2852 contain the same address, it still won't get tried again.) */
2854 if (rc == DEFER || retry_host_key != NULL)
2856 int delete_flag = (rc != DEFER)? rf_delete : 0;
2857 if (retry_host_key == NULL)
2859 retry_host_key = ob->retry_include_ip_address?
2860 string_sprintf("T:%S:%s%s", host->name, host->address, pistring) :
2861 string_sprintf("T:%S%s", host->name, pistring);
2864 /* If a delivery of another message over an existing SMTP connection
2865 yields DEFER, we do NOT set up retry data for the host. This covers the
2866 case when there are delays in routing the addresses in the second message
2867 that are so long that the server times out. This is alleviated by not
2868 routing addresses that previously had routing defers when handling an
2869 existing connection, but even so, this case may occur (e.g. if a
2870 previously happily routed address starts giving routing defers). If the
2871 host is genuinely down, another non-continued message delivery will
2872 notice it soon enough. */
2874 if (delete_flag != 0 || !continuing)
2875 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
2877 /* We may have tried an expired host, if its retry time has come; ensure
2878 the status reflects the expiry for the benefit of any other addresses. */
2882 host->status = (host_is_expired)?
2883 hstatus_unusable_expired : hstatus_unusable;
2884 host->why = hwhy_deferred;
2888 /* If message_defer is set (host was OK, but every recipient got deferred
2889 because of some message-specific problem), or if that had happened
2890 previously so that a message retry key exists, add an appropriate item
2891 to the retry chain. Note that if there was a message defer but now there is
2892 a host defer, the message defer record gets deleted. That seems perfectly
2893 reasonable. Also, stop the message from being remembered as waiting
2894 for specific hosts. */
2896 if (message_defer || retry_message_key != NULL)
2898 int delete_flag = message_defer? 0 : rf_delete;
2899 if (retry_message_key == NULL)
2901 retry_message_key = ob->retry_include_ip_address?
2902 string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
2904 string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
2906 retry_add_item(addrlist, retry_message_key,
2907 rf_message | rf_host | delete_flag);
2908 update_waiting = FALSE;
2911 /* Any return other than DEFER (that is, OK or ERROR) means that the
2912 addresses have got their final statuses filled in for this host. In the OK
2913 case, see if any of them are deferred. */
2917 for (addr = addrlist; addr != NULL; addr = addr->next)
2919 if (addr->transport_return == DEFER)
2921 some_deferred = TRUE;
2927 /* If no addresses deferred or the result was ERROR, return. We do this for
2928 ERROR because a failing filter set-up or add_headers expansion is likely to
2929 fail for any host we try. */
2931 if (rc == ERROR || (rc == OK && !some_deferred))
2933 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
2934 return TRUE; /* Each address has its status */
2937 /* If the result was DEFER or some individual addresses deferred, let
2938 the loop run to try other hosts with the deferred addresses, except for the
2939 case when we were trying to deliver down an existing channel and failed.
2940 Don't try any other hosts in this case. */
2942 if (continuing) break;
2944 /* If the whole delivery, or some individual addresses, were deferred and
2945 there are more hosts that could be tried, do not count this host towards
2946 the hosts_max_try limit if the age of the message is greater than the
2947 maximum retry time for this host. This means we may try try all hosts,
2948 ignoring the limit, when messages have been around for some time. This is
2949 important because if we don't try all hosts, the address will never time
2950 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
2952 if ((rc == DEFER || some_deferred) && nexthost != NULL)
2955 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
2957 if (retry != NULL && retry->rules != NULL)
2959 retry_rule *last_rule;
2960 for (last_rule = retry->rules;
2961 last_rule->next != NULL;
2962 last_rule = last_rule->next);
2963 timedout = time(NULL) - received_time > last_rule->timeout;
2965 else timedout = TRUE; /* No rule => timed out */
2969 unexpired_hosts_tried--;
2970 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
2971 "hosts_max_try (message older than host's retry time)\n");
2974 } /* End of loop for trying multiple hosts. */
2976 /* This is the end of the loop that repeats iff expired is TRUE and
2977 ob->delay_after_cutoff is FALSE. The second time round we will
2978 try those hosts that haven't been tried since the message arrived. */
2982 debug_printf("all IP addresses skipped or deferred at least one address\n");
2983 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
2984 debug_printf("retrying IP addresses not tried since message arrived\n");
2989 /* Get here if all IP addresses are skipped or defer at least one address. In
2990 MUA wrapper mode, this will happen only for connection or other non-message-
2991 specific failures. Force the delivery status for all addresses to FAIL. */
2995 for (addr = addrlist; addr != NULL; addr = addr->next)
2996 addr->transport_return = FAIL;
3000 /* In the normal, non-wrapper case, add a standard message to each deferred
3001 address if there hasn't been an error, that is, if it hasn't actually been
3002 tried this time. The variable "expired" will be FALSE if any deliveries were
3003 actually tried, or if there was at least one host that was not expired. That
3004 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
3005 a delivery has been tried, an error code will be set, and the failing of the
3006 message is handled by the retry code later.
3008 If queue_smtp is set, or this transport was called to send a subsequent message
3009 down an existing TCP/IP connection, and something caused the host not to be
3010 found, we end up here, but can detect these cases and handle them specially. */
3012 for (addr = addrlist; addr != NULL; addr = addr->next)
3014 /* If host is not NULL, it means that we stopped processing the host list
3015 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
3016 means we need to behave as if some hosts were skipped because their retry
3017 time had not come. Specifically, this prevents the address from timing out.
3018 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
3019 hosts were tried. */
3023 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
3026 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
3027 "hosts were tried\n");
3032 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
3033 setflag(addr, af_retry_skipped);
3037 if (queue_smtp) /* no deliveries attempted */
3039 addr->transport_return = DEFER;
3040 addr->basic_errno = 0;
3041 addr->message = US"SMTP delivery explicitly queued";
3044 else if (addr->transport_return == DEFER &&
3045 (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0) &&
3046 addr->message == NULL)
3048 addr->basic_errno = ERRNO_HRETRY;
3049 if (continue_hostname != NULL)
3051 addr->message = US"no host found for existing SMTP connection";
3055 setflag(addr, af_pass_message); /* This is not a security risk */
3056 addr->message = (ob->delay_after_cutoff)?
3057 US"retry time not reached for any host after a long failure period" :
3058 US"all hosts have been failing for a long time and were last tried "
3059 "after this message arrived";
3061 /* If we are already using fallback hosts, or there are no fallback hosts
3062 defined, convert the result to FAIL to cause a bounce. */
3064 if (addr->host_list == addr->fallback_hosts ||
3065 addr->fallback_hosts == NULL)
3066 addr->transport_return = FAIL;
3070 if (hosts_retry == hosts_total)
3071 addr->message = US"retry time not reached for any host";
3072 else if (hosts_fail == hosts_total)
3073 addr->message = US"all host address lookups failed permanently";
3074 else if (hosts_defer == hosts_total)
3075 addr->message = US"all host address lookups failed temporarily";
3076 else if (hosts_serial == hosts_total)
3077 addr->message = US"connection limit reached for all hosts";
3078 else if (hosts_fail+hosts_defer == hosts_total)
3079 addr->message = US"all host address lookups failed";
3080 else addr->message = US"some host address lookups failed and retry time "
3081 "not reached for other hosts or connection limit reached";
3086 /* Update the database which keeps information about which messages are waiting
3087 for which hosts to become available. For some message-specific errors, the
3088 update_waiting flag is turned off because we don't want follow-on deliveries in
3091 if (update_waiting) transport_update_waiting(hostlist, tblock->name);
3095 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3097 return TRUE; /* Each address has its status */
3100 /* End of transport/smtp.c */