1 /* $Cambridge: exim/src/src/transports/smtp.c,v 1.34 2007/02/06 14:19:00 ph10 Exp $ */
3 /*************************************************
4 * Exim - an Internet mail transport agent *
5 *************************************************/
7 /* Copyright (c) University of Cambridge 1995 - 2007 */
8 /* See the file NOTICE for conditions of use and distribution. */
14 #define PENDING_DEFER (PENDING + DEFER)
15 #define PENDING_OK (PENDING + OK)
18 /* Options specific to the smtp transport. This transport also supports LMTP
19 over TCP/IP. The options must be in alphabetic order (note that "_" comes
20 before the lower case letters). Some live in the transport_instance block so as
21 to be publicly visible; these are flagged with opt_public. */
23 optionlist smtp_transport_options[] = {
24 { "address_retry_include_sender", opt_bool,
25 (void *)offsetof(smtp_transport_options_block, address_retry_include_sender) },
26 { "allow_localhost", opt_bool,
27 (void *)offsetof(smtp_transport_options_block, allow_localhost) },
28 { "authenticated_sender", opt_stringptr,
29 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
30 { "authenticated_sender_force", opt_bool,
31 (void *)offsetof(smtp_transport_options_block, authenticated_sender_force) },
32 { "command_timeout", opt_time,
33 (void *)offsetof(smtp_transport_options_block, command_timeout) },
34 { "connect_timeout", opt_time,
35 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
36 { "connection_max_messages", opt_int | opt_public,
37 (void *)offsetof(transport_instance, connection_max_messages) },
38 { "data_timeout", opt_time,
39 (void *)offsetof(smtp_transport_options_block, data_timeout) },
40 { "delay_after_cutoff", opt_bool,
41 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
42 #ifdef EXPERIMENTAL_DOMAINKEYS
43 { "dk_canon", opt_stringptr,
44 (void *)offsetof(smtp_transport_options_block, dk_canon) },
45 { "dk_domain", opt_stringptr,
46 (void *)offsetof(smtp_transport_options_block, dk_domain) },
47 { "dk_headers", opt_stringptr,
48 (void *)offsetof(smtp_transport_options_block, dk_headers) },
49 { "dk_private_key", opt_stringptr,
50 (void *)offsetof(smtp_transport_options_block, dk_private_key) },
51 { "dk_selector", opt_stringptr,
52 (void *)offsetof(smtp_transport_options_block, dk_selector) },
53 { "dk_strict", opt_stringptr,
54 (void *)offsetof(smtp_transport_options_block, dk_strict) },
56 { "dns_qualify_single", opt_bool,
57 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
58 { "dns_search_parents", opt_bool,
59 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
60 { "fallback_hosts", opt_stringptr,
61 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
62 { "final_timeout", opt_time,
63 (void *)offsetof(smtp_transport_options_block, final_timeout) },
64 { "gethostbyname", opt_bool,
65 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
67 { "gnutls_require_kx", opt_stringptr,
68 (void *)offsetof(smtp_transport_options_block, gnutls_require_kx) },
69 { "gnutls_require_mac", opt_stringptr,
70 (void *)offsetof(smtp_transport_options_block, gnutls_require_mac) },
71 { "gnutls_require_protocols", opt_stringptr,
72 (void *)offsetof(smtp_transport_options_block, gnutls_require_proto) },
74 { "helo_data", opt_stringptr,
75 (void *)offsetof(smtp_transport_options_block, helo_data) },
76 { "hosts", opt_stringptr,
77 (void *)offsetof(smtp_transport_options_block, hosts) },
78 { "hosts_avoid_esmtp", opt_stringptr,
79 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
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_esmtp */
164 NULL, /* hosts_nopass_tls */
165 5*60, /* command_timeout */
166 5*60, /* connect_timeout; shorter system default overrides */
167 5*60, /* data timeout */
168 10*60, /* final timeout */
169 1024, /* size_addition */
170 5, /* hosts_max_try */
171 50, /* hosts_max_try_hardlimit */
172 TRUE, /* address_retry_include_sender */
173 FALSE, /* allow_localhost */
174 FALSE, /* authenticated_sender_force */
175 FALSE, /* gethostbyname */
176 TRUE, /* dns_qualify_single */
177 FALSE, /* dns_search_parents */
178 TRUE, /* delay_after_cutoff */
179 FALSE, /* hosts_override */
180 FALSE, /* hosts_randomize */
181 TRUE, /* keepalive */
182 FALSE, /* lmtp_ignore_quota */
183 TRUE /* retry_include_ip_address */
185 ,NULL, /* tls_certificate */
187 NULL, /* tls_privatekey */
188 NULL, /* tls_require_ciphers */
189 NULL, /* gnutls_require_kx */
190 NULL, /* gnutls_require_mac */
191 NULL, /* gnutls_require_proto */
192 NULL, /* tls_verify_certificates */
193 TRUE /* tls_tempfail_tryclear */
195 #ifdef EXPERIMENTAL_DOMAINKEYS
196 ,NULL, /* dk_canon */
197 NULL, /* dk_domain */
198 NULL, /* dk_headers */
199 NULL, /* dk_private_key */
200 NULL, /* dk_selector */
208 static uschar *smtp_command; /* Points to last cmd for error messages */
209 static uschar *mail_command; /* Points to MAIL cmd for error messages */
210 static BOOL update_waiting; /* TRUE to update the "wait" database */
213 /*************************************************
214 * Setup entry point *
215 *************************************************/
217 /* This function is called when the transport is about to be used,
218 but before running it in a sub-process. It is used for two things:
220 (1) To set the fallback host list in addresses, when delivering.
221 (2) To pass back the interface, port, protocol, and other options, for use
222 during callout verification.
225 tblock pointer to the transport instance block
226 addrlist list of addresses about to be transported
227 tf if not NULL, pointer to block in which to return options
228 uid the uid that will be set (not used)
229 gid the gid that will be set (not used)
230 errmsg place for error message (not used)
232 Returns: OK always (FAIL, DEFER not used)
236 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
237 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
239 smtp_transport_options_block *ob =
240 (smtp_transport_options_block *)(tblock->options_block);
242 errmsg = errmsg; /* Keep picky compilers happy */
246 /* Pass back options if required. This interface is getting very messy. */
250 tf->interface = ob->interface;
252 tf->protocol = ob->protocol;
253 tf->hosts = ob->hosts;
254 tf->hosts_override = ob->hosts_override;
255 tf->hosts_randomize = ob->hosts_randomize;
256 tf->gethostbyname = ob->gethostbyname;
257 tf->qualify_single = ob->dns_qualify_single;
258 tf->search_parents = ob->dns_search_parents;
259 tf->helo_data = ob->helo_data;
262 /* Set the fallback host list for all the addresses that don't have fallback
263 host lists, provided that the local host wasn't present in the original host
266 if (!testflag(addrlist, af_local_host_removed))
268 for (; addrlist != NULL; addrlist = addrlist->next)
269 if (addrlist->fallback_hosts == NULL)
270 addrlist->fallback_hosts = ob->fallback_hostlist;
278 /*************************************************
279 * Initialization entry point *
280 *************************************************/
282 /* Called for each instance, after its options have been read, to
283 enable consistency checks to be done, or anything else that needs
286 Argument: pointer to the transport instance block
291 smtp_transport_init(transport_instance *tblock)
293 smtp_transport_options_block *ob =
294 (smtp_transport_options_block *)(tblock->options_block);
296 /* Retry_use_local_part defaults FALSE if unset */
298 if (tblock->retry_use_local_part == TRUE_UNSET)
299 tblock->retry_use_local_part = FALSE;
301 /* Set the default port according to the protocol */
303 if (ob->port == NULL)
304 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" : US"smtp";
306 /* Set up the setup entry point, to be called before subprocesses for this
309 tblock->setup = smtp_transport_setup;
311 /* Complain if any of the timeouts are zero. */
313 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
314 ob->final_timeout <= 0)
315 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
316 "command, data, or final timeout value is zero for %s transport",
319 /* If hosts_override is set and there are local hosts, set the global
320 flag that stops verify from showing router hosts. */
322 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
324 /* If there are any fallback hosts listed, build a chain of host items
325 for them, but do not do any lookups at this time. */
327 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
334 /*************************************************
335 * Set delivery info into all active addresses *
336 *************************************************/
338 /* Only addresses whose status is >= PENDING are relevant. A lesser
339 status means that an address is not currently being processed.
342 addrlist points to a chain of addresses
343 errno_value to put in each address's errno field
344 msg to put in each address's message field
345 rc to put in each address's transport_return field
346 pass_message if TRUE, set the "pass message" flag in the address
348 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
349 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
350 this particular type of timeout.
356 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
361 if (errno_value == ERRNO_CONNECTTIMEOUT)
363 errno_value = ETIMEDOUT;
364 orvalue = RTEF_CTOUT;
366 for (addr = addrlist; addr != NULL; addr = addr->next)
368 if (addr->transport_return < PENDING) continue;
369 addr->basic_errno = errno_value;
370 addr->more_errno |= orvalue;
374 if (pass_message) setflag(addr, af_pass_message);
376 addr->transport_return = rc;
382 /*************************************************
383 * Check an SMTP response *
384 *************************************************/
386 /* This function is given an errno code and the SMTP response buffer
387 to analyse, together with the host identification for generating messages. It
388 sets an appropriate message and puts the first digit of the response code into
389 the yield variable. If no response was actually read, a suitable digit is
393 host the current host, to get its name for messages
394 errno_value pointer to the errno value
395 more_errno from the top address for use with ERRNO_FILTER_FAIL
396 buffer the SMTP response buffer
397 yield where to put a one-digit SMTP response code
398 message where to put an errror message
399 pass_message set TRUE if message is an SMTP response
401 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
404 static BOOL check_response(host_item *host, int *errno_value, int more_errno,
405 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
409 if (smtp_use_pipelining &&
410 (Ustrcmp(smtp_command, "MAIL") == 0 ||
411 Ustrcmp(smtp_command, "RCPT") == 0 ||
412 Ustrcmp(smtp_command, "DATA") == 0))
415 *yield = '4'; /* Default setting is to give a temporary error */
417 /* Handle response timeout */
419 if (*errno_value == ETIMEDOUT)
421 *message = US string_sprintf("SMTP timeout while connected to %s [%s] "
422 "after %s%s", host->name, host->address, pl, smtp_command);
423 if (transport_count > 0)
424 *message = US string_sprintf("%s (%d bytes written)", *message,
429 /* Handle malformed SMTP response */
431 if (*errno_value == ERRNO_SMTPFORMAT)
433 uschar *malfresp = string_printing(buffer);
434 while (isspace(*malfresp)) malfresp++;
436 *message = string_sprintf("Malformed SMTP reply (an empty line) from "
437 "%s [%s] in response to %s%s", host->name, host->address, pl,
440 *message = string_sprintf("Malformed SMTP reply from %s [%s] in response "
441 "to %s%s: %s", host->name, host->address, pl, smtp_command, malfresp);
445 /* Handle a failed filter process error; can't send QUIT as we mustn't
448 if (*errno_value == ERRNO_FILTER_FAIL)
450 *message = US string_sprintf("transport filter process failed (%d)%s",
452 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
456 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
459 if (*errno_value == ERRNO_CHHEADER_FAIL)
462 US string_sprintf("failed to expand headers_add or headers_remove: %s",
463 expand_string_message);
467 /* Handle failure to write a complete data block */
469 if (*errno_value == ERRNO_WRITEINCOMPLETE)
471 *message = US string_sprintf("failed to write a data block");
475 /* Handle error responses from the remote mailer. */
479 uschar *s = string_printing(buffer);
480 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
481 "host %s [%s]: %s", pl, smtp_command, host->name, host->address, s);
482 *pass_message = TRUE;
487 /* No data was read. If there is no errno, this must be the EOF (i.e.
488 connection closed) case, which causes deferral. An explicit connection reset
489 error has the same effect. Otherwise, put the host's identity in the message,
490 leaving the errno value to be interpreted as well. In all cases, we have to
491 assume the connection is now dead. */
493 if (*errno_value == 0 || *errno_value == ECONNRESET)
495 *errno_value = ERRNO_SMTPCLOSED;
496 *message = US string_sprintf("Remote host %s [%s] closed connection "
497 "in response to %s%s", host->name, host->address, pl, smtp_command);
499 else *message = US string_sprintf("%s [%s]", host->name, host->address);
506 /*************************************************
507 * Write error message to logs *
508 *************************************************/
510 /* This writes to the main log and to the message log.
513 addr the address item containing error information
514 host the current host
520 write_logs(address_item *addr, host_item *host)
522 if (addr->message != NULL)
524 uschar *message = addr->message;
525 if (addr->basic_errno > 0)
526 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
527 log_write(0, LOG_MAIN, "%s", message);
528 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
533 ((log_extra_selector & LX_outgoing_port) != 0)?
534 string_sprintf("%s [%s]:%d", host->name, host->address,
535 (host->port == PORT_NONE)? 25 : host->port)
537 string_sprintf("%s [%s]", host->name, host->address);
538 log_write(0, LOG_MAIN, "%s %s", msg, strerror(addr->basic_errno));
539 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), msg,
540 strerror(addr->basic_errno));
546 /*************************************************
547 * Synchronize SMTP responses *
548 *************************************************/
550 /* This function is called from smtp_deliver() to receive SMTP responses from
551 the server, and match them up with the commands to which they relate. When
552 PIPELINING is not in use, this function is called after every command, and is
553 therefore somewhat over-engineered, but it is simpler to use a single scheme
554 that works both with and without PIPELINING instead of having two separate sets
557 The set of commands that are buffered up with pipelining may start with MAIL
558 and may end with DATA; in between are RCPT commands that correspond to the
559 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
560 etc.) are never buffered.
562 Errors after MAIL or DATA abort the whole process leaving the response in the
563 buffer. After MAIL, pending responses are flushed, and the original command is
564 re-instated in big_buffer for error messages. For RCPT commands, the remote is
565 permitted to reject some recipient addresses while accepting others. However
566 certain errors clearly abort the whole process. Set the value in
567 transport_return to PENDING_OK if the address is accepted. If there is a
568 subsequent general error, it will get reset accordingly. If not, it will get
569 converted to OK at the end.
572 addrlist the complete address list
573 include_affixes TRUE if affixes include in RCPT
574 sync_addr ptr to the ptr of the one to start scanning at (updated)
575 host the host we are connected to
576 count the number of responses to read
578 include_sender true if 4xx retry is to include the sender it its key
579 pending_MAIL true if the first response is for MAIL
580 pending_DATA 0 if last command sent was not DATA
581 +1 if previously had a good recipient
582 -1 if not previously had a good recipient
583 inblock incoming SMTP block
584 timeout timeout value
585 buffer buffer for reading response
586 buffsize size of buffer
588 Returns: 3 if at least one address had 2xx and one had 5xx
589 2 if at least one address had 5xx but none had 2xx
590 1 if at least one host had a 2xx response, but none had 5xx
591 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
592 -1 timeout while reading RCPT response
593 -2 I/O or other non-response error for RCPT
594 -3 DATA or MAIL failed - errno and buffer set
598 sync_responses(address_item *addrlist, BOOL include_affixes,
599 address_item **sync_addr, host_item *host, int count,
600 BOOL address_retry_include_sender, BOOL pending_MAIL,
601 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
604 address_item *addr = *sync_addr;
607 /* Handle the response for a MAIL command. On error, reinstate the original
608 command in big_buffer for error message use, and flush any further pending
609 responses before returning, except after I/O errors and timeouts. */
614 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
616 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
617 if (errno == 0 && buffer[0] != 0)
619 uschar flushbuffer[4096];
621 if (buffer[0] == '4')
623 save_errno = ERRNO_MAIL4XX;
624 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
628 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
630 && (errno != 0 || flushbuffer[0] == 0))
639 if (pending_DATA) count--; /* Number of RCPT responses to come */
641 /* Read and handle the required number of RCPT responses, matching each one up
642 with an address by scanning for the next address whose status is PENDING_DEFER.
647 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
649 /* The address was accepted */
651 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
654 addr->transport_return = PENDING_OK;
656 /* If af_dr_retry_exists is set, there was a routing delay on this address;
657 ensure that any address-specific retry record is expunged. We do this both
658 for the basic key and for the version that also includes the sender. */
660 if (testflag(addr, af_dr_retry_exists))
662 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
664 retry_add_item(addr, altkey, rf_delete);
665 retry_add_item(addr, addr->address_retry_key, rf_delete);
669 /* Timeout while reading the response */
671 else if (errno == ETIMEDOUT)
673 int save_errno = errno;
674 uschar *message = string_sprintf("SMTP timeout while connected to %s [%s] "
675 "after RCPT TO:<%s>", host->name, host->address,
676 transport_rcpt_address(addr, include_affixes));
677 set_errno(addrlist, save_errno, message, DEFER, FALSE);
678 retry_add_item(addr, addr->address_retry_key, 0);
679 update_waiting = FALSE;
683 /* Handle other errors in obtaining an SMTP response by returning -1. This
684 will cause all the addresses to be deferred. Restore the SMTP command in
685 big_buffer for which we are checking the response, so the error message
688 else if (errno != 0 || buffer[0] == 0)
690 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
691 transport_rcpt_address(addr, include_affixes));
695 /* Handle SMTP permanent and temporary response codes. */
700 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
701 "host %s [%s]: %s", transport_rcpt_address(addr, include_affixes),
702 host->name, host->address, string_printing(buffer));
703 setflag(addr, af_pass_message);
704 deliver_msglog("%s %s\n", tod_stamp(tod_log), addr->message);
706 /* The response was 5xx */
708 if (buffer[0] == '5')
710 addr->transport_return = FAIL;
714 /* The response was 4xx */
718 addr->transport_return = DEFER;
719 addr->basic_errno = ERRNO_RCPT4XX;
720 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
722 /* Log temporary errors if there are more hosts to be tried. */
724 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", addr->message);
726 /* Do not put this message on the list of those waiting for specific
727 hosts, as otherwise it is likely to be tried too often. */
729 update_waiting = FALSE;
731 /* Add a retry item for the address so that it doesn't get tried again
732 too soon. If address_retry_include_sender is true, add the sender address
735 if (address_retry_include_sender)
737 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
739 retry_add_item(addr, altkey, 0);
741 else retry_add_item(addr, addr->address_retry_key, 0);
744 } /* Loop for next RCPT response */
746 /* Update where to start at for the next block of responses, unless we
747 have already handled all the addresses. */
749 if (addr != NULL) *sync_addr = addr->next;
751 /* Handle a response to DATA. If we have not had any good recipients, either
752 previously or in this block, the response is ignored. */
754 if (pending_DATA != 0 &&
755 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
760 if (pending_DATA > 0 || (yield & 1) != 0)
762 if (errno == 0 && buffer[0] == '4')
764 errno = ERRNO_DATA4XX;
765 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
769 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
770 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
771 "is in use and there were no good recipients\n", msg);
774 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
775 present) received 3xx. If any RCPTs were handled and yielded anything other
776 than 4xx, yield will be set non-zero. */
783 /*************************************************
784 * Deliver address list to given host *
785 *************************************************/
787 /* If continue_hostname is not null, we get here only when continuing to
788 deliver down an existing channel. The channel was passed as the standard
791 Otherwise, we have to make a connection to the remote host, and do the
792 initial protocol exchange.
794 When running as an MUA wrapper, if the sender or any recipient is rejected,
795 temporarily or permanently, we force failure for all recipients.
798 addrlist chain of potential addresses to deliver; only those whose
799 transport_return field is set to PENDING_DEFER are currently
800 being processed; others should be skipped - they have either
801 been delivered to an earlier host or IP address, or been
802 failed by one of them.
803 host host to deliver to
804 host_af AF_INET or AF_INET6
805 port default TCP/IP port to use, in host byte order
806 interface interface to bind to, or NULL
807 tblock transport instance block
808 copy_host TRUE if host set in addr->host_used must be copied, because
809 it is specific to this call of the transport
810 message_defer set TRUE if yield is OK, but all addresses were deferred
811 because of a non-recipient, non-host failure, that is, a
812 4xx response to MAIL FROM, DATA, or ".". This is a defer
813 that is specific to the message.
814 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
815 a second attempt after TLS initialization fails
817 Returns: OK - the connection was made and the delivery attempted;
818 the result for each address is in its data block.
819 DEFER - the connection could not be made, or something failed
820 while setting up the SMTP session, or there was a
821 non-message-specific error, such as a timeout.
822 ERROR - a filter command is specified for this transport,
823 and there was a problem setting it up; OR helo_data
824 or add_headers or authenticated_sender is specified
825 for this transport, and the string failed to expand
829 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
830 uschar *interface, transport_instance *tblock, BOOL copy_host,
831 BOOL *message_defer, BOOL suppress_tls)
834 address_item *sync_addr;
835 address_item *first_addr = addrlist;
840 time_t start_delivery_time = time(NULL);
841 smtp_transport_options_block *ob =
842 (smtp_transport_options_block *)(tblock->options_block);
843 BOOL lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
845 BOOL send_rset = TRUE;
846 BOOL send_quit = TRUE;
847 BOOL setting_up = TRUE;
848 BOOL completed_address = FALSE;
851 BOOL pass_message = FALSE;
852 smtp_inblock inblock;
853 smtp_outblock outblock;
854 int max_rcpt = tblock->max_addresses;
855 uschar *igquotstr = US"";
856 uschar *local_authenticated_sender = authenticated_sender;
857 uschar *helo_data = NULL;
858 uschar *message = NULL;
859 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
862 uschar inbuffer[4096];
863 uschar outbuffer[1024];
865 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
867 *message_defer = FALSE;
868 smtp_command = US"initial connection";
869 if (max_rcpt == 0) max_rcpt = 999999;
871 /* Set up the buffer for reading SMTP response packets. */
873 inblock.buffer = inbuffer;
874 inblock.buffersize = sizeof(inbuffer);
875 inblock.ptr = inbuffer;
876 inblock.ptrend = inbuffer;
878 /* Set up the buffer for holding SMTP commands while pipelining */
880 outblock.buffer = outbuffer;
881 outblock.buffersize = sizeof(outbuffer);
882 outblock.ptr = outbuffer;
883 outblock.cmd_count = 0;
884 outblock.authenticating = FALSE;
886 /* If an authenticated_sender override has been specified for this transport
887 instance, expand it. If the expansion is forced to fail, and there was already
888 an authenticated_sender for this message, the original value will be used.
889 Other expansion failures are serious. An empty result is ignored, but there is
890 otherwise no check - this feature is expected to be used with LMTP and other
891 cases where non-standard addresses (e.g. without domains) might be required. */
893 if (ob->authenticated_sender != NULL)
895 uschar *new = expand_string(ob->authenticated_sender);
898 if (!expand_string_forcedfail)
900 uschar *message = string_sprintf("failed to expand "
901 "authenticated_sender: %s", expand_string_message);
902 set_errno(addrlist, 0, message, DEFER, FALSE);
906 else if (new[0] != 0) local_authenticated_sender = new;
909 /* Make a connection to the host if this isn't a continued delivery, and handle
910 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
911 specially so they can be identified for retries. */
913 if (continue_hostname == NULL)
915 inblock.sock = outblock.sock =
916 smtp_connect(host, host_af, port, interface, ob->connect_timeout,
918 if (inblock.sock < 0)
920 set_errno(addrlist, (errno == ETIMEDOUT)? ERRNO_CONNECTTIMEOUT : errno,
925 /* Expand the greeting message while waiting for the initial response. (Makes
926 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
927 delayed till here so that $sending_interface and $sending_port are set. */
929 helo_data = expand_string(ob->helo_data);
931 /* The first thing is to wait for an initial OK response. The dreaded "goto"
932 is nevertheless a reasonably clean way of programming this kind of logic,
933 where you want to escape on any error. */
935 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
936 ob->command_timeout)) goto RESPONSE_FAILED;
938 /* Now check if the helo_data expansion went well, and sign off cleanly if it
941 if (helo_data == NULL)
943 uschar *message = string_sprintf("failed to expand helo_data: %s",
944 expand_string_message);
945 set_errno(addrlist, 0, message, DEFER, FALSE);
950 /** Debugging without sending a message
951 addrlist->transport_return = DEFER;
955 /* Errors that occur after this point follow an SMTP command, which is
956 left in big_buffer by smtp_write_command() for use in error messages. */
958 smtp_command = big_buffer;
960 /* Tell the remote who we are...
962 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
963 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
964 greeting is of this form. The assumption was that the far end supports it
965 properly... but experience shows that there are some that give 5xx responses,
966 even though the banner includes "ESMTP" (there's a bloody-minded one that
967 says "ESMTP not spoken here"). Cope with that case.
969 September 2000: Time has passed, and it seems reasonable now to always send
970 EHLO at the start. It is also convenient to make the change while installing
973 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
974 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
975 would be no way to send out the mails, so there is now a host list
976 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
977 PIPELINING problem as well. Maybe it can also be useful to cure other
978 problems with broken servers.
980 Exim originally sent "Helo" at this point and ran for nearly a year that way.
981 Then somebody tried it with a Microsoft mailer... It seems that all other
982 mailers use upper case for some reason (the RFC is quite clear about case
983 independence) so, for peace of mind, I gave in. */
985 esmtp = verify_check_this_host(&(ob->hosts_avoid_esmtp), NULL,
986 host->name, host->address, NULL) != OK;
990 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
991 lmtp? "LHLO" : "EHLO", helo_data) < 0)
993 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
994 ob->command_timeout))
996 if (errno != 0 || buffer[0] == 0 || lmtp) goto RESPONSE_FAILED;
1003 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1008 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1010 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1011 ob->command_timeout)) goto RESPONSE_FAILED;
1014 /* Set IGNOREQUOTA if the response to LHLO specifies support and the
1015 lmtp_ignore_quota option was set. */
1017 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1018 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1019 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1021 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1024 tls_offered = esmtp &&
1025 pcre_exec(regex_STARTTLS, NULL, CS buffer, Ustrlen(buffer), 0,
1026 PCRE_EOPT, NULL, 0) >= 0;
1030 /* For continuing deliveries down the same channel, the socket is the standard
1031 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1032 below). Set up the pointer to where subsequent commands will be left, for
1033 error messages. Note that smtp_use_size and smtp_use_pipelining will have been
1034 set from the command line if they were set in the process that passed the
1039 inblock.sock = outblock.sock = fileno(stdin);
1040 smtp_command = big_buffer;
1043 /* If TLS is available on this connection, whether continued or not, attempt to
1044 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1045 send another EHLO - the server may give a different answer in secure mode. We
1046 use a separate buffer for reading the response to STARTTLS so that if it is
1047 negative, the original EHLO data is available for subsequent analysis, should
1048 the client not be required to use TLS. If the response is bad, copy the buffer
1049 for error analysis. */
1052 if (tls_offered && !suppress_tls &&
1053 verify_check_this_host(&(ob->hosts_avoid_tls), NULL, host->name,
1054 host->address, NULL) != OK)
1056 uschar buffer2[4096];
1057 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1060 /* If there is an I/O error, transmission of this message is deferred. If
1061 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1062 false, we also defer. However, if there is a temporary rejection of STARTTLS
1063 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1064 STARTTLS, we carry on. This means we will try to send the message in clear,
1065 unless the host is in hosts_require_tls (tested below). */
1067 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1068 ob->command_timeout))
1070 Ustrncpy(buffer, buffer2, sizeof(buffer));
1071 if (errno != 0 || buffer2[0] == 0 ||
1072 (buffer2[0] == '4' && !ob->tls_tempfail_tryclear))
1073 goto RESPONSE_FAILED;
1076 /* STARTTLS accepted: try to negotiate a TLS session. */
1080 int rc = tls_client_start(inblock.sock,
1083 NULL, /* No DH param */
1084 ob->tls_certificate,
1086 ob->tls_verify_certificates,
1088 ob->tls_require_ciphers,
1089 ob->gnutls_require_mac,
1090 ob->gnutls_require_kx,
1091 ob->gnutls_require_proto,
1092 ob->command_timeout);
1094 /* TLS negotiation failed; give an error. From outside, this function may
1095 be called again to try in clear on a new connection, if the options permit
1096 it for this host. */
1100 save_errno = ERRNO_TLSFAILURE;
1101 message = US"failure while setting up TLS session";
1106 /* TLS session is set up */
1108 for (addr = addrlist; addr != NULL; addr = addr->next)
1110 if (addr->transport_return == PENDING_DEFER)
1112 addr->cipher = tls_cipher;
1113 addr->peerdn = tls_peerdn;
1119 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1120 helo_data is null, we are dealing with a connection that was passed from
1121 another process, and so we won't have expanded helo_data above. We have to
1122 expand it here. $sending_ip_address and $sending_port are set up right at the
1123 start of the Exim process (in exim.c). */
1125 if (tls_active >= 0)
1127 if (helo_data == NULL)
1129 helo_data = expand_string(ob->helo_data);
1130 if (helo_data == NULL)
1132 uschar *message = string_sprintf("failed to expand helo_data: %s",
1133 expand_string_message);
1134 set_errno(addrlist, 0, message, DEFER, FALSE);
1140 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n", lmtp? "LHLO" : "EHLO",
1143 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1144 ob->command_timeout))
1145 goto RESPONSE_FAILED;
1148 /* If the host is required to use a secure channel, ensure that we
1151 else if (verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
1152 host->address, NULL) == OK)
1154 save_errno = ERRNO_TLSREQUIRED;
1155 message = string_sprintf("a TLS session is required for %s [%s], but %s",
1156 host->name, host->address,
1157 tls_offered? "an attempt to start TLS failed" :
1158 "the server did not offer TLS support");
1163 /* If TLS is active, we have just started it up and re-done the EHLO command,
1164 so its response needs to be analyzed. If TLS is not active and this is a
1165 continued session down a previously-used socket, we haven't just done EHLO, so
1168 if (continue_hostname == NULL
1175 uschar *fail_reason = US"server did not advertise AUTH support";
1177 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
1178 lmtp_ignore_quota option was set. */
1180 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1181 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1182 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1184 /* If the response to EHLO specified support for the SIZE parameter, note
1185 this, provided size_addition is non-negative. */
1187 smtp_use_size = esmtp && ob->size_addition >= 0 &&
1188 pcre_exec(regex_SIZE, NULL, CS buffer, Ustrlen(CS buffer), 0,
1189 PCRE_EOPT, NULL, 0) >= 0;
1191 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
1192 the current host, esmtp will be false, so PIPELINING can never be used. */
1194 smtp_use_pipelining = esmtp &&
1195 pcre_exec(regex_PIPELINING, NULL, CS buffer, Ustrlen(CS buffer), 0,
1196 PCRE_EOPT, NULL, 0) >= 0;
1198 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
1199 smtp_use_pipelining? "" : "not ");
1201 /* Note if the response to EHLO specifies support for the AUTH extension.
1202 If it has, check that this host is one we want to authenticate to, and do
1203 the business. The host name and address must be available when the
1204 authenticator's client driver is running. */
1206 smtp_authenticated = FALSE;
1207 require_auth = verify_check_this_host(&(ob->hosts_require_auth), NULL,
1208 host->name, host->address, NULL);
1210 if (esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
1212 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
1213 expand_nmax = -1; /* reset */
1215 /* Must not do this check until after we have saved the result of the
1216 regex match above. */
1218 if (require_auth == OK ||
1219 verify_check_this_host(&(ob->hosts_try_auth), NULL, host->name,
1220 host->address, NULL) == OK)
1223 fail_reason = US"no common mechanisms were found";
1225 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1227 /* Scan the configured authenticators looking for one which is configured
1228 for use as a client and whose name matches an authentication mechanism
1229 supported by the server. If one is found, attempt to authenticate by
1230 calling its client function. */
1232 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1235 if (!au->client) continue;
1237 /* Loop to scan supported server mechanisms */
1242 int len = Ustrlen(au->public_name);
1243 while (isspace(*p)) p++;
1245 if (strncmpic(au->public_name, p, len) != 0 ||
1246 (p[len] != 0 && !isspace(p[len])))
1248 while (*p != 0 && !isspace(*p)) p++;
1252 /* Found data for a listed mechanism. Call its client entry. Set
1253 a flag in the outblock so that data is overwritten after sending so
1254 that reflections don't show it. */
1256 fail_reason = US"authentication attempt(s) failed";
1257 outblock.authenticating = TRUE;
1258 rc = (au->info->clientcode)(au, &inblock, &outblock,
1259 ob->command_timeout, buffer, sizeof(buffer));
1260 outblock.authenticating = FALSE;
1261 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1264 /* A temporary authentication failure must hold up delivery to
1265 this host. After a permanent authentication failure, we carry on
1266 to try other authentication methods. If all fail hard, try to
1267 deliver the message unauthenticated unless require_auth was set. */
1272 smtp_authenticated = TRUE; /* stops the outer loop */
1275 /* Failure after writing a command */
1280 /* Failure after reading a response */
1283 if (errno != 0 || buffer[0] != '5') goto RESPONSE_FAILED;
1284 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1285 au->name, host->name, host->address, buffer);
1288 /* Failure by some other means. In effect, the authenticator
1289 decided it wasn't prepared to handle this case. Typically this
1290 is the result of "fail" in an expansion string. Do we need to
1291 log anything here? Feb 2006: a message is now put in the buffer
1292 if logging is required. */
1296 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1297 "authentication H=%s [%s] %s", au->name, host->name,
1298 host->address, buffer);
1301 /* Internal problem, message in buffer. */
1305 set_errno(addrlist, 0, string_copy(buffer), DEFER, FALSE);
1309 break; /* If not authenticated, try next authenticator */
1310 } /* Loop for scanning supported server mechanisms */
1311 } /* Loop for further authenticators */
1315 /* If we haven't authenticated, but are required to, give up. */
1317 if (require_auth == OK && !smtp_authenticated)
1320 set_errno(addrlist, ERRNO_AUTHFAIL,
1321 string_sprintf("authentication required but %s", fail_reason), DEFER,
1327 /* The setting up of the SMTP call is now complete. Any subsequent errors are
1328 message-specific. */
1332 /* If there is a filter command specified for this transport, we can now
1333 set it up. This cannot be done until the identify of the host is known. */
1335 if (tblock->filter_command != NULL)
1339 sprintf(CS buffer, "%.50s transport", tblock->name);
1340 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
1341 TRUE, DEFER, addrlist, buffer, NULL);
1343 /* On failure, copy the error to all addresses, abandon the SMTP call, and
1348 set_errno(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
1356 /* For messages that have more than the maximum number of envelope recipients,
1357 we want to send several transactions down the same SMTP connection. (See
1358 comments in deliver.c as to how this reconciles, heuristically, with
1359 remote_max_parallel.) This optimization was added to Exim after the following
1360 code was already working. The simplest way to put it in without disturbing the
1361 code was to use a goto to jump back to this point when there is another
1362 transaction to handle. */
1365 sync_addr = first_addr;
1369 completed_address = FALSE;
1372 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
1373 qualification, send it, adding something to the message size to allow for
1374 imprecision and things that get added en route. Exim keeps the number of lines
1375 in a message, so we can give an accurate value for the original message, but we
1376 need some additional to handle added headers. (Double "." characters don't get
1377 included in the count.) */
1384 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
1388 /* Add the authenticated sender address if present */
1390 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1391 local_authenticated_sender != NULL)
1393 string_format(p, sizeof(buffer) - (p-buffer), " AUTH=%s",
1394 auth_xtextencode(local_authenticated_sender,
1395 Ustrlen(local_authenticated_sender)));
1398 /* From here until we send the DATA command, we can make use of PIPELINING
1399 if the server host supports it. The code has to be able to check the responses
1400 at any point, for when the buffer fills up, so we write it totally generally.
1401 When PIPELINING is off, each command written reports that it has flushed the
1404 pending_MAIL = TRUE; /* The block starts with MAIL */
1406 rc = smtp_write_command(&outblock, smtp_use_pipelining,
1407 "MAIL FROM:<%s>%s\r\n", return_path, buffer);
1408 mail_command = string_copy(big_buffer); /* Save for later error message */
1412 case -1: /* Transmission error */
1415 case +1: /* Block was sent */
1416 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1417 ob->command_timeout))
1419 if (errno == 0 && buffer[0] == '4')
1421 errno = ERRNO_MAIL4XX;
1422 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1424 goto RESPONSE_FAILED;
1426 pending_MAIL = FALSE;
1430 /* Pass over all the relevant recipient addresses for this host, which are the
1431 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
1432 several before we have to read the responses for those seen so far. This
1433 checking is done by a subroutine because it also needs to be done at the end.
1434 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
1435 the next one if not all are sent.
1437 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
1438 last address because we want to abort if any recipients have any kind of
1439 problem, temporary or permanent. We know that all recipient addresses will have
1440 the PENDING_DEFER status, because only one attempt is ever made, and we know
1441 that max_rcpt will be large, so all addresses will be done at once. */
1443 for (addr = first_addr;
1444 address_count < max_rcpt && addr != NULL;
1450 if (addr->transport_return != PENDING_DEFER) continue;
1453 no_flush = smtp_use_pipelining && (!mua_wrapper || addr->next != NULL);
1455 /* Now send the RCPT command, and process outstanding responses when
1456 necessary. After a timeout on RCPT, we just end the function, leaving the
1457 yield as OK, because this error can often mean that there is a problem with
1458 just one address, so we don't want to delay the host. */
1460 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s\r\n",
1461 transport_rcpt_address(addr, tblock->rcpt_include_affixes), igquotstr);
1462 if (count < 0) goto SEND_FAILED;
1465 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
1466 &sync_addr, host, count, ob->address_retry_include_sender,
1467 pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
1470 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1471 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1474 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1475 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1476 case 0: /* No 2xx or 5xx, but no probs */
1479 case -1: goto END_OFF; /* Timeout on RCPT */
1480 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
1482 pending_MAIL = FALSE; /* Dealt with MAIL */
1484 } /* Loop for next address */
1486 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
1487 permanently or temporarily. We should have flushed and synced after the last
1492 address_item *badaddr;
1493 for (badaddr = first_addr; badaddr != NULL; badaddr = badaddr->next)
1495 if (badaddr->transport_return != PENDING_OK) break;
1497 if (badaddr != NULL)
1499 set_errno(addrlist, 0, badaddr->message, FAIL,
1500 testflag(badaddr, af_pass_message));
1505 /* If ok is TRUE, we know we have got at least one good recipient, and must now
1506 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
1507 have a good recipient buffered up if we are pipelining. We don't want to waste
1508 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
1509 are pipelining. The responses are all handled by sync_responses(). */
1511 if (ok || (smtp_use_pipelining && !mua_wrapper))
1513 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
1514 if (count < 0) goto SEND_FAILED;
1515 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
1516 host, count, ob->address_retry_include_sender, pending_MAIL,
1517 ok? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
1519 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1520 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1523 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1524 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1525 case 0: break; /* No 2xx or 5xx, but no probs */
1527 case -1: goto END_OFF; /* Timeout on RCPT */
1528 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
1532 /* Save the first address of the next batch. */
1536 /* If there were no good recipients (but otherwise there have been no
1537 problems), just set ok TRUE, since we have handled address-specific errors
1538 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
1539 for handling the SMTP dot-handling protocol, flagging to apply to headers as
1540 well as body. Set the appropriate timeout value to be used for each chunk.
1541 (Haven't been able to make it work using select() for writing yet.) */
1543 if (!ok) ok = TRUE; else
1545 sigalrm_seen = FALSE;
1546 transport_write_timeout = ob->data_timeout;
1547 smtp_command = US"sending data block"; /* For error messages */
1548 DEBUG(D_transport|D_v)
1549 debug_printf(" SMTP>> writing message and terminating \".\"\n");
1550 transport_count = 0;
1551 #ifdef EXPERIMENTAL_DOMAINKEYS
1552 if ( (ob->dk_private_key != NULL) && (ob->dk_selector != NULL) )
1553 ok = dk_transport_write_message(addrlist, inblock.sock,
1554 topt_use_crlf | topt_end_dot | topt_escape_headers |
1555 (tblock->body_only? topt_no_headers : 0) |
1556 (tblock->headers_only? topt_no_body : 0) |
1557 (tblock->return_path_add? topt_add_return_path : 0) |
1558 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1559 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1560 0, /* No size limit */
1561 tblock->add_headers, tblock->remove_headers,
1562 US".", US"..", /* Escaping strings */
1563 tblock->rewrite_rules, tblock->rewrite_existflags,
1564 ob->dk_private_key, ob->dk_domain, ob->dk_selector,
1565 ob->dk_canon, ob->dk_headers, ob->dk_strict);
1568 ok = transport_write_message(addrlist, inblock.sock,
1569 topt_use_crlf | topt_end_dot | topt_escape_headers |
1570 (tblock->body_only? topt_no_headers : 0) |
1571 (tblock->headers_only? topt_no_body : 0) |
1572 (tblock->return_path_add? topt_add_return_path : 0) |
1573 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1574 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1575 0, /* No size limit */
1576 tblock->add_headers, tblock->remove_headers,
1577 US".", US"..", /* Escaping strings */
1578 tblock->rewrite_rules, tblock->rewrite_existflags);
1580 /* transport_write_message() uses write() because it is called from other
1581 places to write to non-sockets. This means that under some OS (e.g. Solaris)
1582 it can exit with "Broken pipe" as its error. This really means that the
1583 socket got closed at the far end. */
1585 transport_write_timeout = 0; /* for subsequent transports */
1587 /* Failure can either be some kind of I/O disaster (including timeout),
1588 or the failure of a transport filter or the expansion of added headers. */
1592 buffer[0] = 0; /* There hasn't been a response */
1593 goto RESPONSE_FAILED;
1596 /* We used to send the terminating "." explicitly here, but because of
1597 buffering effects at both ends of TCP/IP connections, you don't gain
1598 anything by keeping it separate, so it might as well go in the final
1599 data buffer for efficiency. This is now done by setting the topt_end_dot
1602 smtp_command = US"end of data";
1604 /* For SMTP, we now read a single response that applies to the whole message.
1605 If it is OK, then all the addresses have been delivered. */
1609 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1611 if (!ok && errno == 0 && buffer[0] == '4')
1613 errno = ERRNO_DATA4XX;
1614 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1618 /* For LMTP, we get back a response for every RCPT command that we sent;
1619 some may be accepted and some rejected. For those that get a response, their
1620 status is fixed; any that are accepted have been handed over, even if later
1621 responses crash - at least, that's how I read RFC 2033.
1623 If all went well, mark the recipient addresses as completed, record which
1624 host/IPaddress they were delivered to, and cut out RSET when sending another
1625 message down the same channel. Write the completed addresses to the journal
1626 now so that they are recorded in case there is a crash of hardware or
1627 software before the spool gets updated. Also record the final SMTP
1628 confirmation if needed (for SMTP only). */
1633 int delivery_time = (int)(time(NULL) - start_delivery_time);
1636 uschar *conf = NULL;
1639 /* Make a copy of the host if it is local to this invocation
1640 of the transport. */
1644 thost = store_get(sizeof(host_item));
1646 thost->name = string_copy(host->name);
1647 thost->address = string_copy(host->address);
1651 /* Set up confirmation if needed - applies only to SMTP */
1653 if ((log_extra_selector & LX_smtp_confirmation) != 0 && !lmtp)
1655 uschar *s = string_printing(buffer);
1656 conf = (s == buffer)? (uschar *)string_copy(s) : s;
1659 /* Process all transported addresses - for LMTP, read a status for
1662 for (addr = addrlist; addr != first_addr; addr = addr->next)
1664 if (addr->transport_return != PENDING_OK) continue;
1666 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
1667 remaining addresses. Otherwise, it's a return code for just the one
1668 address. For temporary errors, add a retry item for the address so that
1669 it doesn't get tried again too soon. */
1673 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1676 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
1677 addr->message = string_sprintf("LMTP error after %s: %s",
1678 big_buffer, string_printing(buffer));
1679 setflag(addr, af_pass_message); /* Allow message to go to user */
1680 if (buffer[0] == '5')
1681 addr->transport_return = FAIL;
1684 errno = ERRNO_DATA4XX;
1685 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1686 addr->transport_return = DEFER;
1687 retry_add_item(addr, addr->address_retry_key, 0);
1691 completed_address = TRUE; /* NOW we can set this flag */
1694 /* SMTP, or success return from LMTP for this address. Pass back the
1695 actual host that was used. */
1697 addr->transport_return = OK;
1698 addr->more_errno = delivery_time;
1699 addr->host_used = thost;
1700 addr->special_action = flag;
1701 addr->message = conf;
1704 /* Update the journal. For homonymic addresses, use the base address plus
1705 the transport name. See lots of comments in deliver.c about the reasons
1706 for the complications when homonyms are involved. Just carry on after
1707 write error, as it may prove possible to update the spool file later. */
1709 if (testflag(addr, af_homonym))
1710 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
1712 sprintf(CS buffer, "%.500s\n", addr->unique);
1714 DEBUG(D_deliver) debug_printf("journalling %s", buffer);
1715 len = Ustrlen(CS buffer);
1716 if (write(journal_fd, buffer, len) != len)
1717 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
1718 "%s: %s", buffer, strerror(errno));
1721 /* Ensure the journal file is pushed out to disk. */
1723 if (EXIMfsync(journal_fd) < 0)
1724 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
1730 /* Handle general (not specific to one address) failures here. The value of ok
1731 is used to skip over this code on the falling through case. A timeout causes a
1732 deferral. Other errors may defer or fail according to the response code, and
1733 may set up a special errno value, e.g. after connection chopped, which is
1734 assumed if errno == 0 and there is no text in the buffer. If control reaches
1735 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
1736 the problem is not related to this specific message. */
1745 send_quit = check_response(host, &save_errno, addrlist->more_errno,
1746 buffer, &code, &message, &pass_message);
1752 message = US string_sprintf("send() to %s [%s] failed: %s",
1753 host->name, host->address, strerror(save_errno));
1757 /* This label is jumped to directly when a TLS negotiation has failed,
1758 or was not done for a host for which it is required. Values will be set
1759 in message and save_errno, and setting_up will always be true. Treat as
1760 a temporary error. */
1767 /* If the failure happened while setting up the call, see if the failure was
1768 a 5xx response (this will either be on connection, or following HELO - a 5xx
1769 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
1770 never going to accept them. For other errors during setting up (timeouts or
1771 whatever), defer all addresses, and yield DEFER, so that the host is not
1772 tried again for a while. */
1775 ok = FALSE; /* For when reached by GOTO */
1781 set_errno(addrlist, save_errno, message, FAIL, pass_message);
1785 set_errno(addrlist, save_errno, message, DEFER, pass_message);
1790 /* We want to handle timeouts after MAIL or "." and loss of connection after
1791 "." specially. They can indicate a problem with the sender address or with
1792 the contents of the message rather than a real error on the connection. These
1793 cases are treated in the same way as a 4xx response. This next bit of code
1794 does the classification. */
1805 message_error = TRUE;
1809 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
1810 Ustrncmp(smtp_command,"end ",4) == 0;
1813 case ERRNO_SMTPCLOSED:
1814 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
1818 message_error = FALSE;
1822 /* Handle the cases that are treated as message errors. These are:
1824 (a) negative response or timeout after MAIL
1825 (b) negative response after DATA
1826 (c) negative response or timeout or dropped connection after "."
1828 It won't be a negative response or timeout after RCPT, as that is dealt
1829 with separately above. The action in all cases is to set an appropriate
1830 error code for all the addresses, but to leave yield set to OK because the
1831 host itself has not failed. Of course, it might in practice have failed
1832 when we've had a timeout, but if so, we'll discover that at the next
1833 delivery attempt. For a temporary error, set the message_defer flag, and
1834 write to the logs for information if this is not the last host. The error
1835 for the last host will be logged as part of the address's log line. */
1839 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
1840 set_errno(addrlist, save_errno, message, (code == '5')? FAIL : DEFER,
1843 /* If there's an errno, the message contains just the identity of
1846 if (code != '5') /* Anything other than 5 is treated as temporary */
1849 message = US string_sprintf("%s: %s", message, strerror(save_errno));
1850 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
1851 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
1852 *message_defer = TRUE;
1856 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
1857 ".", or some other transportation error. We defer all addresses and yield
1858 DEFER, except for the case of failed add_headers expansion, or a transport
1859 filter failure, when the yield should be ERROR, to stop it trying other
1864 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
1865 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
1866 set_errno(addrlist, save_errno, message, DEFER, pass_message);
1872 /* If all has gone well, send_quit will be set TRUE, implying we can end the
1873 SMTP session tidily. However, if there were too many addresses to send in one
1874 message (indicated by first_addr being non-NULL) we want to carry on with the
1875 rest of them. Also, it is desirable to send more than one message down the SMTP
1876 connection if there are several waiting, provided we haven't already sent so
1877 many as to hit the configured limit. The function transport_check_waiting looks
1878 for a waiting message and returns its id. Then transport_pass_socket tries to
1879 set up a continued delivery by passing the socket on to another process. The
1880 variable send_rset is FALSE if a message has just been successfully transfered.
1882 If we are already sending down a continued channel, there may be further
1883 addresses not yet delivered that are aimed at the same host, but which have not
1884 been passed in this run of the transport. In this case, continue_more will be
1885 true, and all we should do is send RSET if necessary, and return, leaving the
1888 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
1889 do not want to continue with other messages down the same channel, because that
1890 can lead to looping between two or more messages, all with the same,
1891 temporarily failing address(es). [The retry information isn't updated yet, so
1892 new processes keep on trying.] We probably also don't want to try more of this
1893 message's addresses either.
1895 If we have started a TLS session, we have to end it before passing the
1896 connection to a new process. However, not all servers can handle this (Exim
1897 can), so we do not pass such a connection on if the host matches
1898 hosts_nopass_tls. */
1901 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
1902 "yield=%d first_address is %sNULL\n", ok, send_quit, send_rset,
1903 continue_more, yield, (first_addr == NULL)? "":"not ");
1905 if (completed_address && ok && send_quit)
1908 if (first_addr != NULL || continue_more ||
1911 verify_check_this_host(&(ob->hosts_nopass_tls), NULL, host->name,
1912 host->address, NULL) != OK)
1914 transport_check_waiting(tblock->name, host->name,
1915 tblock->connection_max_messages, new_message_id, &more)
1923 if (! (ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
1925 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
1926 host->address, strerror(save_errno));
1929 else if (! (ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1930 ob->command_timeout)))
1933 send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
1937 DEBUG(D_transport) debug_printf("%s\n", msg);
1942 /* Either RSET was not needed, or it succeeded */
1946 if (first_addr != NULL) /* More addresses still to be sent */
1947 { /* in this run of the transport */
1948 continue_sequence++; /* Causes * in logging */
1951 if (continue_more) return yield; /* More addresses for another run */
1953 /* Pass the socket to a new Exim process. Before doing so, we must shut
1954 down TLS. Not all MTAs allow for the continuation of the SMTP session
1955 when TLS is shut down. We test for this by sending a new EHLO. If we
1956 don't get a good response, we don't attempt to pass the socket on. */
1959 if (tls_active >= 0)
1962 ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
1963 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1964 ob->command_timeout);
1968 /* If the socket is successfully passed, we musn't send QUIT (or
1969 indeed anything!) from here. */
1971 if (ok && transport_pass_socket(tblock->name, host->name, host->address,
1972 new_message_id, inblock.sock))
1978 /* If RSET failed and there are addresses left, they get deferred. */
1980 else set_errno(first_addr, errno, msg, DEFER, FALSE);
1984 /* End off tidily with QUIT unless the connection has died or the socket has
1985 been passed to another process. There has been discussion on the net about what
1986 to do after sending QUIT. The wording of the RFC suggests that it is necessary
1987 to wait for a response, but on the other hand, there isn't anything one can do
1988 with an error response, other than log it. Exim used to do that. However,
1989 further discussion suggested that it is positively advantageous not to wait for
1990 the response, but to close the session immediately. This is supposed to move
1991 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
1992 load from the server. (Hosts that are both servers and clients may not see much
1993 difference, of course.) Further discussion indicated that this was safe to do
1994 on Unix systems which have decent implementations of TCP/IP that leave the
1995 connection around for a while (TIME_WAIT) after the application has gone away.
1996 This enables the response sent by the server to be properly ACKed rather than
1997 timed out, as can happen on broken TCP/IP implementations on other OS.
1999 This change is being made on 31-Jul-98. After over a year of trouble-free
2000 operation, the old commented-out code was removed on 17-Sep-99. */
2003 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2011 /* Close the socket, and return the appropriate value, first setting
2012 continue_transport and continue_hostname NULL to prevent any other addresses
2013 that may include the host from trying to re-use a continuation socket. This
2014 works because the NULL setting is passed back to the calling process, and
2015 remote_max_parallel is forced to 1 when delivering over an existing connection,
2017 If all went well and continue_more is set, we shouldn't actually get here if
2018 there are further addresses, as the return above will be taken. However,
2019 writing RSET might have failed, or there may be other addresses whose hosts are
2020 specified in the transports, and therefore not visible at top level, in which
2021 case continue_more won't get set. */
2023 (void)close(inblock.sock);
2024 continue_transport = NULL;
2025 continue_hostname = NULL;
2032 /*************************************************
2033 * Closedown entry point *
2034 *************************************************/
2036 /* This function is called when exim is passed an open smtp channel
2037 from another incarnation, but the message which it has been asked
2038 to deliver no longer exists. The channel is on stdin.
2040 We might do fancy things like looking for another message to send down
2041 the channel, but if the one we sought has gone, it has probably been
2042 delivered by some other process that itself will seek further messages,
2043 so just close down our connection.
2045 Argument: pointer to the transport instance block
2050 smtp_transport_closedown(transport_instance *tblock)
2052 smtp_transport_options_block *ob =
2053 (smtp_transport_options_block *)(tblock->options_block);
2054 smtp_inblock inblock;
2055 smtp_outblock outblock;
2057 uschar inbuffer[4096];
2058 uschar outbuffer[16];
2060 inblock.sock = fileno(stdin);
2061 inblock.buffer = inbuffer;
2062 inblock.buffersize = sizeof(inbuffer);
2063 inblock.ptr = inbuffer;
2064 inblock.ptrend = inbuffer;
2066 outblock.sock = inblock.sock;
2067 outblock.buffersize = sizeof(outbuffer);
2068 outblock.buffer = outbuffer;
2069 outblock.ptr = outbuffer;
2070 outblock.cmd_count = 0;
2071 outblock.authenticating = FALSE;
2073 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2074 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2075 ob->command_timeout);
2076 (void)close(inblock.sock);
2081 /*************************************************
2082 * Prepare addresses for delivery *
2083 *************************************************/
2085 /* This function is called to flush out error settings from previous delivery
2086 attempts to other hosts. It also records whether we got here via an MX record
2087 or not in the more_errno field of the address. We are interested only in
2088 addresses that are still marked DEFER - others may have got delivered to a
2089 previously considered IP address. Set their status to PENDING_DEFER to indicate
2090 which ones are relevant this time.
2093 addrlist the list of addresses
2094 host the host we are delivering to
2096 Returns: the first address for this delivery
2099 static address_item *
2100 prepare_addresses(address_item *addrlist, host_item *host)
2102 address_item *first_addr = NULL;
2104 for (addr = addrlist; addr != NULL; addr = addr->next)
2106 if (addr->transport_return != DEFER) continue;
2107 if (first_addr == NULL) first_addr = addr;
2108 addr->transport_return = PENDING_DEFER;
2109 addr->basic_errno = 0;
2110 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
2111 addr->message = NULL;
2113 addr->cipher = NULL;
2114 addr->peerdn = NULL;
2122 /*************************************************
2123 * Main entry point *
2124 *************************************************/
2126 /* See local README for interface details. As this is a remote transport, it is
2127 given a chain of addresses to be delivered in one connection, if possible. It
2128 always returns TRUE, indicating that each address has its own independent
2129 status set, except if there is a setting up problem, in which case it returns
2133 smtp_transport_entry(
2134 transport_instance *tblock, /* data for this instantiation */
2135 address_item *addrlist) /* addresses we are working on */
2139 int hosts_defer = 0;
2141 int hosts_looked_up = 0;
2142 int hosts_retry = 0;
2143 int hosts_serial = 0;
2144 int hosts_total = 0;
2145 int total_hosts_tried = 0;
2147 BOOL expired = TRUE;
2148 BOOL continuing = continue_hostname != NULL;
2149 uschar *expanded_hosts = NULL;
2151 uschar *tid = string_sprintf("%s transport", tblock->name);
2152 smtp_transport_options_block *ob =
2153 (smtp_transport_options_block *)(tblock->options_block);
2154 host_item *hostlist = addrlist->host_list;
2155 host_item *host = NULL;
2159 debug_printf("%s transport entered\n", tblock->name);
2160 for (addr = addrlist; addr != NULL; addr = addr->next)
2161 debug_printf(" %s\n", addr->address);
2162 if (continuing) debug_printf("already connected to %s [%s]\n",
2163 continue_hostname, continue_host_address);
2166 /* Set the flag requesting that these hosts be added to the waiting
2167 database if the delivery fails temporarily or if we are running with
2168 queue_smtp or a 2-stage queue run. This gets unset for certain
2169 kinds of error, typically those that are specific to the message. */
2171 update_waiting = TRUE;
2173 /* If a host list is not defined for the addresses - they must all have the
2174 same one in order to be passed to a single transport - or if the transport has
2175 a host list with hosts_override set, use the host list supplied with the
2176 transport. It is an error for this not to exist. */
2178 if (hostlist == NULL || (ob->hosts_override && ob->hosts != NULL))
2180 if (ob->hosts == NULL)
2182 addrlist->message = string_sprintf("%s transport called with no hosts set",
2184 addrlist->transport_return = PANIC;
2185 return FALSE; /* Only top address has status */
2188 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
2191 /* If the transport's host list contains no '$' characters, and we are not
2192 randomizing, it is fixed and therefore a chain of hosts can be built once
2193 and for all, and remembered for subsequent use by other calls to this
2194 transport. If, on the other hand, the host list does contain '$', or we are
2195 randomizing its order, we have to rebuild it each time. In the fixed case,
2196 as the hosts string will never be used again, it doesn't matter that we
2197 replace all the : characters with zeros. */
2199 if (ob->hostlist == NULL)
2201 uschar *s = ob->hosts;
2203 if (Ustrchr(s, '$') != NULL)
2205 expanded_hosts = expand_string(s);
2206 if (expanded_hosts == NULL)
2208 addrlist->message = string_sprintf("failed to expand list of hosts "
2209 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
2210 addrlist->transport_return = search_find_defer? DEFER : PANIC;
2211 return FALSE; /* Only top address has status */
2213 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
2214 "\"%s\"\n", s, expanded_hosts);
2218 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
2220 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
2222 /* If there was no expansion of hosts, save the host list for
2225 if (expanded_hosts == NULL) ob->hostlist = hostlist;
2228 /* This is not the first time this transport has been run in this delivery;
2229 the host list was built previously. */
2231 else hostlist = ob->hostlist;
2234 /* The host list was supplied with the address. If hosts_randomize is set, we
2235 must sort it into a random order if it did not come from MX records and has not
2236 already been randomized (but don't bother if continuing down an existing
2239 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continuing)
2241 host_item *newlist = NULL;
2242 while (hostlist != NULL)
2244 host_item *h = hostlist;
2245 hostlist = hostlist->next;
2247 h->sort_key = random_number(100);
2249 if (newlist == NULL)
2254 else if (h->sort_key < newlist->sort_key)
2261 host_item *hh = newlist;
2262 while (hh->next != NULL)
2264 if (h->sort_key < hh->next->sort_key) break;
2272 hostlist = addrlist->host_list = newlist;
2276 /* Sort out the default port. */
2278 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
2281 /* For each host-plus-IP-address on the list:
2283 . If this is a continued delivery and the host isn't the one with the
2284 current connection, skip.
2286 . If the status is unusable (i.e. previously failed or retry checked), skip.
2288 . If no IP address set, get the address, either by turning the name into
2289 an address, calling gethostbyname if gethostbyname is on, or by calling
2290 the DNS. The DNS may yield multiple addresses, in which case insert the
2291 extra ones into the list.
2293 . Get the retry data if not previously obtained for this address and set the
2294 field which remembers the state of this address. Skip if the retry time is
2295 not reached. If not, remember whether retry data was found. The retry string
2296 contains both the name and the IP address.
2298 . Scan the list of addresses and mark those whose status is DEFER as
2299 PENDING_DEFER. These are the only ones that will be processed in this cycle
2302 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
2303 Some addresses may be successfully delivered, others may fail, and yet
2304 others may get temporary errors and so get marked DEFER.
2306 . The return from the delivery attempt is OK if a connection was made and a
2307 valid SMTP dialogue was completed. Otherwise it is DEFER.
2309 . If OK, add a "remove" retry item for this host/IPaddress, if any.
2311 . If fail to connect, or other defer state, add a retry item.
2313 . If there are any addresses whose status is still DEFER, carry on to the
2314 next host/IPaddress, unless we have tried the number of hosts given
2315 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
2316 there is some fancy logic for hosts_max_try that means its limit can be
2317 overstepped in some circumstances.
2319 If we get to the end of the list, all hosts have deferred at least one address,
2320 or not reached their retry times. If delay_after_cutoff is unset, it requests a
2321 delivery attempt to those hosts whose last try was before the arrival time of
2322 the current message. To cope with this, we have to go round the loop a second
2323 time. After that, set the status and error data for any addresses that haven't
2324 had it set already. */
2326 for (cutoff_retry = 0; expired &&
2327 cutoff_retry < ((ob->delay_after_cutoff)? 1 : 2);
2330 host_item *nexthost = NULL;
2331 int unexpired_hosts_tried = 0;
2333 for (host = hostlist;
2335 unexpired_hosts_tried < ob->hosts_max_try &&
2336 total_hosts_tried < ob->hosts_max_try_hardlimit;
2342 BOOL serialized = FALSE;
2343 BOOL host_is_expired = FALSE;
2344 BOOL message_defer = FALSE;
2345 BOOL ifchanges = FALSE;
2346 BOOL some_deferred = FALSE;
2347 address_item *first_addr = NULL;
2348 uschar *interface = NULL;
2349 uschar *retry_host_key = NULL;
2350 uschar *retry_message_key = NULL;
2351 uschar *serialize_key = NULL;
2353 /* Default next host is next host. :-) But this can vary if the
2354 hosts_max_try limit is hit (see below). It may also be reset if a host
2355 address is looked up here (in case the host was multihomed). */
2357 nexthost = host->next;
2359 /* If the address hasn't yet been obtained from the host name, look it up
2360 now, unless the host is already marked as unusable. If it is marked as
2361 unusable, it means that the router was unable to find its IP address (in
2362 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
2363 the lookup failed last time. We don't get this far if *all* MX records
2364 point to non-existent hosts; that is treated as a hard error.
2366 We can just skip this host entirely. When the hosts came from the router,
2367 the address will timeout based on the other host(s); when the address is
2368 looked up below, there is an explicit retry record added.
2370 Note that we mustn't skip unusable hosts if the address is not unset; they
2371 may be needed as expired hosts on the 2nd time round the cutoff loop. */
2373 if (host->address == NULL)
2375 int new_port, flags;
2377 uschar *canonical_name;
2379 if (host->status >= hstatus_unusable)
2381 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
2386 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
2388 /* The host name is permitted to have an attached port. Find it, and
2389 strip it from the name. Just remember it for now. */
2391 new_port = host_item_get_port(host);
2393 /* Count hosts looked up */
2397 /* Find by name if so configured, or if it's an IP address. We don't
2398 just copy the IP address, because we need the test-for-local to happen. */
2400 flags = HOST_FIND_BY_A;
2401 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
2402 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
2404 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
2405 rc = host_find_byname(host, NULL, flags, &canonical_name, TRUE);
2407 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
2408 &canonical_name, NULL);
2410 /* Update the host (and any additional blocks, resulting from
2411 multihoming) with a host-specific port, if any. */
2413 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
2415 /* Failure to find the host at this time (usually DNS temporary failure)
2416 is really a kind of routing failure rather than a transport failure.
2417 Therefore we add a retry item of the routing kind, not to stop us trying
2418 to look this name up here again, but to ensure the address gets timed
2419 out if the failures go on long enough. A complete failure at this point
2420 commonly points to a configuration error, but the best action is still
2421 to carry on for the next host. */
2423 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
2425 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
2427 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
2428 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
2429 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
2430 host->status = hstatus_unusable;
2432 for (addr = addrlist; addr != NULL; addr = addr->next)
2434 if (addr->transport_return != DEFER) continue;
2435 addr->basic_errno = ERRNO_UNKNOWNHOST;
2437 string_sprintf("failed to lookup IP address for %s", host->name);
2442 /* If the host is actually the local host, we may have a problem, or
2443 there may be some cunning configuration going on. In the problem case,
2444 log things and give up. The default transport status is already DEFER. */
2446 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
2448 for (addr = addrlist; addr != NULL; addr = addr->next)
2450 addr->basic_errno = 0;
2451 addr->message = string_sprintf("%s transport found host %s to be "
2452 "local", tblock->name, host->name);
2456 } /* End of block for IP address lookup */
2458 /* If this is a continued delivery, we are interested only in the host
2459 which matches the name of the existing open channel. The check is put
2460 here after the local host lookup, in case the name gets expanded as a
2461 result of the lookup. Set expired FALSE, to save the outer loop executing
2464 if (continuing && (Ustrcmp(continue_hostname, host->name) != 0 ||
2465 Ustrcmp(continue_host_address, host->address) != 0))
2468 continue; /* With next host */
2471 /* Reset the default next host in case a multihomed host whose addresses
2472 are not looked up till just above added to the host list. */
2474 nexthost = host->next;
2476 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
2477 domain is in queue_smtp_domains, we don't actually want to attempt any
2478 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
2479 there is a lookup defer in queue_smtp_domains, proceed as if the domain
2480 were not in it. We don't want to hold up all SMTP deliveries! Except when
2481 doing a two-stage queue run, don't do this if forcing. */
2483 if ((!deliver_force || queue_2stage) && (queue_smtp ||
2484 match_isinlist(addrlist->domain, &queue_smtp_domains, 0,
2485 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
2488 for (addr = addrlist; addr != NULL; addr = addr->next)
2490 if (addr->transport_return != DEFER) continue;
2491 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
2493 continue; /* With next host */
2496 /* Count hosts being considered - purely for an intelligent comment
2497 if none are usable. */
2501 /* Set $host and $host address now in case they are needed for the
2502 interface expansion or the serialize_hosts check; they remain set if an
2503 actual delivery happens. */
2505 deliver_host = host->name;
2506 deliver_host_address = host->address;
2508 /* Set up a string for adding to the retry key if the port number is not
2509 the standard SMTP port. A host may have its own port setting that overrides
2512 pistring = string_sprintf(":%d", (host->port == PORT_NONE)?
2514 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
2516 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
2517 string changes upon expansion, we must add it to the key that is used for
2518 retries, because connections to the same host from a different interface
2519 should be treated separately. */
2521 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET : AF_INET6;
2522 if (!smtp_get_interface(ob->interface, host_af, addrlist, &ifchanges,
2525 if (ifchanges) pistring = string_sprintf("%s/%s", pistring, interface);
2527 /* The first time round the outer loop, check the status of the host by
2528 inspecting the retry data. The second time round, we are interested only
2529 in expired hosts that haven't been tried since this message arrived. */
2531 if (cutoff_retry == 0)
2533 /* Ensure the status of the address is set by checking retry data if
2534 necessary. There maybe host-specific retry data (applicable to all
2535 messages) and also data for retries of a specific message at this host.
2536 If either of these retry records are actually read, the keys used are
2537 returned to save recomputing them later. */
2539 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
2540 ob->retry_include_ip_address, &retry_host_key, &retry_message_key);
2542 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
2543 (host->address == NULL)? US"" : host->address, pistring,
2544 (host->status == hstatus_usable)? "usable" :
2545 (host->status == hstatus_unusable)? "unusable" :
2546 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
2548 /* Skip this address if not usable at this time, noting if it wasn't
2549 actually expired, both locally and in the address. */
2551 switch (host->status)
2553 case hstatus_unusable:
2555 setflag(addrlist, af_retry_skipped);
2558 case hstatus_unusable_expired:
2561 case hwhy_retry: hosts_retry++; break;
2562 case hwhy_failed: hosts_fail++; break;
2563 case hwhy_deferred: hosts_defer++; break;
2566 /* If there was a retry message key, implying that previously there
2567 was a message-specific defer, we don't want to update the list of
2568 messages waiting for these hosts. */
2570 if (retry_message_key != NULL) update_waiting = FALSE;
2571 continue; /* With the next host or IP address */
2575 /* Second time round the loop: if the address is set but expired, and
2576 the message is newer than the last try, let it through. */
2580 if (host->address == NULL ||
2581 host->status != hstatus_unusable_expired ||
2582 host->last_try > received_time)
2585 debug_printf("trying expired host %s [%s]%s\n",
2586 host->name, host->address, pistring);
2587 host_is_expired = TRUE;
2590 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
2591 it remains TRUE only if all hosts are expired and none are actually tried.
2596 /* If this host is listed as one to which access must be serialized,
2597 see if another Exim process has a connection to it, and if so, skip
2598 this host. If not, update the database to record our connection to it
2599 and remember this for later deletion. Do not do any of this if we are
2600 sending the message down a pre-existing connection. */
2603 verify_check_this_host(&(ob->serialize_hosts), NULL, host->name,
2604 host->address, NULL) == OK)
2606 serialize_key = string_sprintf("host-serialize-%s", host->name);
2607 if (!enq_start(serialize_key))
2610 debug_printf("skipping host %s because another Exim process "
2611 "is connected to it\n", host->name);
2618 /* OK, we have an IP address that is not waiting for its retry time to
2619 arrive (it might be expired) OR (second time round the loop) we have an
2620 expired host that hasn't been tried since the message arrived. Have a go
2621 at delivering the message to it. First prepare the addresses by flushing
2622 out the result of previous attempts, and finding the first address that
2623 is still to be delivered. */
2625 first_addr = prepare_addresses(addrlist, host);
2627 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
2628 message_id, host->name, host->address, addrlist->address,
2629 (addrlist->next == NULL)? "" : ", ...");
2631 set_process_info("delivering %s to %s [%s] (%s%s)",
2632 message_id, host->name, host->address, addrlist->address,
2633 (addrlist->next == NULL)? "" : ", ...");
2635 /* This is not for real; don't do the delivery. If there are
2636 any remaining hosts, list them. */
2641 set_errno(addrlist, 0, NULL, OK, FALSE);
2642 for (addr = addrlist; addr != NULL; addr = addr->next)
2644 addr->host_used = host;
2645 addr->special_action = '*';
2646 addr->message = US"delivery bypassed by -N option";
2650 debug_printf("*** delivery by %s transport bypassed by -N option\n"
2651 "*** host and remaining hosts:\n", tblock->name);
2652 for (host2 = host; host2 != NULL; host2 = host2->next)
2653 debug_printf(" %s [%s]\n", host2->name,
2654 (host2->address == NULL)? US"unset" : host2->address);
2659 /* This is for real. If the host is expired, we don't count it for
2660 hosts_max_retry. This ensures that all hosts must expire before an address
2661 is timed out, unless hosts_max_try_hardlimit (which protects against
2662 lunatic DNS configurations) is reached.
2664 If the host is not expired and we are about to hit the hosts_max_retry
2665 limit, check to see if there is a subsequent hosts with a different MX
2666 value. If so, make that the next host, and don't count this one. This is a
2667 heuristic to make sure that different MXs do get tried. With a normal kind
2668 of retry rule, they would get tried anyway when the earlier hosts were
2669 delayed, but if the domain has a "retry every time" type of rule - as is
2670 often used for the the very large ISPs, that won't happen. */
2674 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
2678 debug_printf("hosts_max_try limit reached with this host\n");
2679 for (h = host; h != NULL; h = h->next)
2680 if (h->mx != host->mx) break;
2684 unexpired_hosts_tried--;
2685 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
2686 "and will be tried\n");
2690 /* Attempt the delivery. */
2692 total_hosts_tried++;
2693 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
2694 expanded_hosts != NULL, &message_defer, FALSE);
2697 OK => connection made, each address contains its result;
2698 message_defer is set for message-specific defers (when all
2699 recipients are marked defer)
2700 DEFER => there was a non-message-specific delivery problem;
2701 ERROR => there was a problem setting up the arguments for a filter,
2702 or there was a problem with expanding added headers
2705 /* If the result is not OK, there was a non-message-specific problem.
2706 If the result is DEFER, we need to write to the logs saying what happened
2707 for this particular host, except in the case of authentication and TLS
2708 failures, where the log has already been written. If all hosts defer a
2709 general message is written at the end. */
2711 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL &&
2712 first_addr->basic_errno != ERRNO_TLSFAILURE)
2713 write_logs(first_addr, host);
2715 /* If STARTTLS was accepted, but there was a failure in setting up the
2716 TLS session (usually a certificate screwup), and the host is not in
2717 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
2718 TLS forcibly turned off. We have to start from scratch with a new SMTP
2719 connection. That's why the retry is done from here, not from within
2720 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
2721 session, so the in-clear transmission after those errors, if permitted,
2722 happens inside smtp_deliver().] */
2725 if (rc == DEFER && first_addr->basic_errno == ERRNO_TLSFAILURE &&
2726 ob->tls_tempfail_tryclear &&
2727 verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
2728 host->address, NULL) != OK)
2730 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
2731 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
2732 first_addr = prepare_addresses(addrlist, host);
2733 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
2734 expanded_hosts != NULL, &message_defer, TRUE);
2735 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
2736 write_logs(first_addr, host);
2741 /* Delivery attempt finished */
2743 rs = (rc == OK)? US"OK" : (rc == DEFER)? US"DEFER" : (rc == ERROR)?
2746 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
2747 message_id, host->name, host->address, addrlist->address,
2748 (addrlist->next == NULL)? "" : " (& others)", rs);
2750 /* Release serialization if set up */
2752 if (serialized) enq_end(serialize_key);
2754 /* If the result is DEFER, or if a host retry record is known to exist, we
2755 need to add an item to the retry chain for updating the retry database
2756 at the end of delivery. We only need to add the item to the top address,
2757 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
2758 for any other delivery attempts using the same address. (It is copied into
2759 the unusable tree at the outer level, so even if different address blocks
2760 contain the same address, it still won't get tried again.) */
2762 if (rc == DEFER || retry_host_key != NULL)
2764 int delete_flag = (rc != DEFER)? rf_delete : 0;
2765 if (retry_host_key == NULL)
2767 retry_host_key = ob->retry_include_ip_address?
2768 string_sprintf("T:%S:%s%s", host->name, host->address, pistring) :
2769 string_sprintf("T:%S%s", host->name, pistring);
2772 /* If a delivery of another message over an existing SMTP connection
2773 yields DEFER, we do NOT set up retry data for the host. This covers the
2774 case when there are delays in routing the addresses in the second message
2775 that are so long that the server times out. This is alleviated by not
2776 routing addresses that previously had routing defers when handling an
2777 existing connection, but even so, this case may occur (e.g. if a
2778 previously happily routed address starts giving routing defers). If the
2779 host is genuinely down, another non-continued message delivery will
2780 notice it soon enough. */
2782 if (delete_flag != 0 || !continuing)
2783 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
2785 /* We may have tried an expired host, if its retry time has come; ensure
2786 the status reflects the expiry for the benefit of any other addresses. */
2790 host->status = (host_is_expired)?
2791 hstatus_unusable_expired : hstatus_unusable;
2792 host->why = hwhy_deferred;
2796 /* If message_defer is set (host was OK, but every recipient got deferred
2797 because of some message-specific problem), or if that had happened
2798 previously so that a message retry key exists, add an appropriate item
2799 to the retry chain. Note that if there was a message defer but now there is
2800 a host defer, the message defer record gets deleted. That seems perfectly
2801 reasonable. Also, stop the message from being remembered as waiting
2802 for specific hosts. */
2804 if (message_defer || retry_message_key != NULL)
2806 int delete_flag = message_defer? 0 : rf_delete;
2807 if (retry_message_key == NULL)
2809 retry_message_key = ob->retry_include_ip_address?
2810 string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
2812 string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
2814 retry_add_item(addrlist, retry_message_key,
2815 rf_message | rf_host | delete_flag);
2816 update_waiting = FALSE;
2819 /* Any return other than DEFER (that is, OK or ERROR) means that the
2820 addresses have got their final statuses filled in for this host. In the OK
2821 case, see if any of them are deferred. */
2825 for (addr = addrlist; addr != NULL; addr = addr->next)
2827 if (addr->transport_return == DEFER)
2829 some_deferred = TRUE;
2835 /* If no addresses deferred or the result was ERROR, return. We do this for
2836 ERROR because a failing filter set-up or add_headers expansion is likely to
2837 fail for any host we try. */
2839 if (rc == ERROR || (rc == OK && !some_deferred))
2841 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
2842 return TRUE; /* Each address has its status */
2845 /* If the result was DEFER or some individual addresses deferred, let
2846 the loop run to try other hosts with the deferred addresses, except for the
2847 case when we were trying to deliver down an existing channel and failed.
2848 Don't try any other hosts in this case. */
2850 if (continuing) break;
2852 /* If the whole delivery, or some individual addresses, were deferred and
2853 there are more hosts that could be tried, do not count this host towards
2854 the hosts_max_try limit if the age of the message is greater than the
2855 maximum retry time for this host. This means we may try try all hosts,
2856 ignoring the limit, when messages have been around for some time. This is
2857 important because if we don't try all hosts, the address will never time
2858 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
2860 if ((rc == DEFER || some_deferred) && nexthost != NULL)
2863 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
2865 if (retry != NULL && retry->rules != NULL)
2867 retry_rule *last_rule;
2868 for (last_rule = retry->rules;
2869 last_rule->next != NULL;
2870 last_rule = last_rule->next);
2871 timedout = time(NULL) - received_time > last_rule->timeout;
2873 else timedout = TRUE; /* No rule => timed out */
2877 unexpired_hosts_tried--;
2878 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
2879 "hosts_max_try (message older than host's retry time)\n");
2882 } /* End of loop for trying multiple hosts. */
2884 /* This is the end of the loop that repeats iff expired is TRUE and
2885 ob->delay_after_cutoff is FALSE. The second time round we will
2886 try those hosts that haven't been tried since the message arrived. */
2890 debug_printf("all IP addresses skipped or deferred at least one address\n");
2891 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
2892 debug_printf("retrying IP addresses not tried since message arrived\n");
2897 /* Get here if all IP addresses are skipped or defer at least one address. In
2898 MUA wrapper mode, this will happen only for connection or other non-message-
2899 specific failures. Force the delivery status for all addresses to FAIL. */
2903 for (addr = addrlist; addr != NULL; addr = addr->next)
2904 addr->transport_return = FAIL;
2908 /* In the normal, non-wrapper case, add a standard message to each deferred
2909 address if there hasn't been an error, that is, if it hasn't actually been
2910 tried this time. The variable "expired" will be FALSE if any deliveries were
2911 actually tried, or if there was at least one host that was not expired. That
2912 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
2913 a delivery has been tried, an error code will be set, and the failing of the
2914 message is handled by the retry code later.
2916 If queue_smtp is set, or this transport was called to send a subsequent message
2917 down an existing TCP/IP connection, and something caused the host not to be
2918 found, we end up here, but can detect these cases and handle them specially. */
2920 for (addr = addrlist; addr != NULL; addr = addr->next)
2922 /* If host is not NULL, it means that we stopped processing the host list
2923 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
2924 means we need to behave as if some hosts were skipped because their retry
2925 time had not come. Specifically, this prevents the address from timing out.
2926 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
2927 hosts were tried. */
2931 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
2934 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
2935 "hosts were tried\n");
2940 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
2941 setflag(addr, af_retry_skipped);
2945 if (queue_smtp) /* no deliveries attempted */
2947 addr->transport_return = DEFER;
2948 addr->basic_errno = 0;
2949 addr->message = US"SMTP delivery explicitly queued";
2952 else if (addr->transport_return == DEFER &&
2953 (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0) &&
2954 addr->message == NULL)
2956 addr->basic_errno = ERRNO_HRETRY;
2957 if (continue_hostname != NULL)
2959 addr->message = US"no host found for existing SMTP connection";
2963 setflag(addr, af_pass_message); /* This is not a security risk */
2964 addr->message = (ob->delay_after_cutoff)?
2965 US"retry time not reached for any host after a long failure period" :
2966 US"all hosts have been failing for a long time and were last tried "
2967 "after this message arrived";
2969 /* If we are already using fallback hosts, or there are no fallback hosts
2970 defined, convert the result to FAIL to cause a bounce. */
2972 if (addr->host_list == addr->fallback_hosts ||
2973 addr->fallback_hosts == NULL)
2974 addr->transport_return = FAIL;
2978 if (hosts_retry == hosts_total)
2979 addr->message = US"retry time not reached for any host";
2980 else if (hosts_fail == hosts_total)
2981 addr->message = US"all host address lookups failed permanently";
2982 else if (hosts_defer == hosts_total)
2983 addr->message = US"all host address lookups failed temporarily";
2984 else if (hosts_serial == hosts_total)
2985 addr->message = US"connection limit reached for all hosts";
2986 else if (hosts_fail+hosts_defer == hosts_total)
2987 addr->message = US"all host address lookups failed";
2988 else addr->message = US"some host address lookups failed and retry time "
2989 "not reached for other hosts or connection limit reached";
2994 /* Update the database which keeps information about which messages are waiting
2995 for which hosts to become available. For some message-specific errors, the
2996 update_waiting flag is turned off because we don't want follow-on deliveries in
2999 if (update_waiting) transport_update_waiting(hostlist, tblock->name);
3003 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3005 return TRUE; /* Each address has its status */
3008 /* End of transport/smtp.c */
git://git.exim.org / exim.git / blob