1 /* $Cambridge: exim/src/src/transports/smtp.c,v 1.41 2009/01/02 17:22:12 nm4 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 #if (defined EXPERIMENTAL_DOMAINKEYS) || (defined EXPERIMENTAL_DKIM)
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) },
55 { "dkim_canon", opt_stringptr,
56 (void *)offsetof(smtp_transport_options_block, dkim_canon) },
57 { "dkim_domain", opt_stringptr,
58 (void *)offsetof(smtp_transport_options_block, dkim_domain) },
59 { "dkim_private_key", opt_stringptr,
60 (void *)offsetof(smtp_transport_options_block, dkim_private_key) },
61 { "dkim_selector", opt_stringptr,
62 (void *)offsetof(smtp_transport_options_block, dkim_selector) },
63 { "dkim_sign_headers", opt_stringptr,
64 (void *)offsetof(smtp_transport_options_block, dkim_sign_headers) },
65 { "dkim_strict", opt_stringptr,
66 (void *)offsetof(smtp_transport_options_block, dkim_strict) },
68 { "dns_qualify_single", opt_bool,
69 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
70 { "dns_search_parents", opt_bool,
71 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
72 { "fallback_hosts", opt_stringptr,
73 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
74 { "final_timeout", opt_time,
75 (void *)offsetof(smtp_transport_options_block, final_timeout) },
76 { "gethostbyname", opt_bool,
77 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
79 { "gnutls_require_kx", opt_stringptr,
80 (void *)offsetof(smtp_transport_options_block, gnutls_require_kx) },
81 { "gnutls_require_mac", opt_stringptr,
82 (void *)offsetof(smtp_transport_options_block, gnutls_require_mac) },
83 { "gnutls_require_protocols", opt_stringptr,
84 (void *)offsetof(smtp_transport_options_block, gnutls_require_proto) },
86 { "helo_data", opt_stringptr,
87 (void *)offsetof(smtp_transport_options_block, helo_data) },
88 { "hosts", opt_stringptr,
89 (void *)offsetof(smtp_transport_options_block, hosts) },
90 { "hosts_avoid_esmtp", opt_stringptr,
91 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
92 { "hosts_avoid_pipelining", opt_stringptr,
93 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
95 { "hosts_avoid_tls", opt_stringptr,
96 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
98 { "hosts_max_try", opt_int,
99 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
100 { "hosts_max_try_hardlimit", opt_int,
101 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
103 { "hosts_nopass_tls", opt_stringptr,
104 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
106 { "hosts_override", opt_bool,
107 (void *)offsetof(smtp_transport_options_block, hosts_override) },
108 { "hosts_randomize", opt_bool,
109 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
110 { "hosts_require_auth", opt_stringptr,
111 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
113 { "hosts_require_tls", opt_stringptr,
114 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
116 { "hosts_try_auth", opt_stringptr,
117 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
118 { "interface", opt_stringptr,
119 (void *)offsetof(smtp_transport_options_block, interface) },
120 { "keepalive", opt_bool,
121 (void *)offsetof(smtp_transport_options_block, keepalive) },
122 { "lmtp_ignore_quota", opt_bool,
123 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
124 { "max_rcpt", opt_int | opt_public,
125 (void *)offsetof(transport_instance, max_addresses) },
126 { "multi_domain", opt_bool | opt_public,
127 (void *)offsetof(transport_instance, multi_domain) },
128 { "port", opt_stringptr,
129 (void *)offsetof(smtp_transport_options_block, port) },
130 { "protocol", opt_stringptr,
131 (void *)offsetof(smtp_transport_options_block, protocol) },
132 { "retry_include_ip_address", opt_bool,
133 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
134 { "serialize_hosts", opt_stringptr,
135 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
136 { "size_addition", opt_int,
137 (void *)offsetof(smtp_transport_options_block, size_addition) }
139 ,{ "tls_certificate", opt_stringptr,
140 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
141 { "tls_crl", opt_stringptr,
142 (void *)offsetof(smtp_transport_options_block, tls_crl) },
143 { "tls_privatekey", opt_stringptr,
144 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
145 { "tls_require_ciphers", opt_stringptr,
146 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
147 { "tls_tempfail_tryclear", opt_bool,
148 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
149 { "tls_verify_certificates", opt_stringptr,
150 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) }
154 /* Size of the options list. An extern variable has to be used so that its
155 address can appear in the tables drtables.c. */
157 int smtp_transport_options_count =
158 sizeof(smtp_transport_options)/sizeof(optionlist);
160 /* Default private options block for the smtp transport. */
162 smtp_transport_options_block smtp_transport_option_defaults = {
164 NULL, /* fallback_hosts */
166 NULL, /* fallback_hostlist */
167 NULL, /* authenticated_sender */
168 US"$primary_hostname", /* helo_data */
169 NULL, /* interface */
171 US"smtp", /* protocol */
172 NULL, /* serialize_hosts */
173 NULL, /* hosts_try_auth */
174 NULL, /* hosts_require_auth */
175 NULL, /* hosts_require_tls */
176 NULL, /* hosts_avoid_tls */
177 NULL, /* hosts_avoid_pipelining */
178 NULL, /* hosts_avoid_esmtp */
179 NULL, /* hosts_nopass_tls */
180 5*60, /* command_timeout */
181 5*60, /* connect_timeout; shorter system default overrides */
182 5*60, /* data timeout */
183 10*60, /* final timeout */
184 1024, /* size_addition */
185 5, /* hosts_max_try */
186 50, /* hosts_max_try_hardlimit */
187 TRUE, /* address_retry_include_sender */
188 FALSE, /* allow_localhost */
189 FALSE, /* authenticated_sender_force */
190 FALSE, /* gethostbyname */
191 TRUE, /* dns_qualify_single */
192 FALSE, /* dns_search_parents */
193 TRUE, /* delay_after_cutoff */
194 FALSE, /* hosts_override */
195 FALSE, /* hosts_randomize */
196 TRUE, /* keepalive */
197 FALSE, /* lmtp_ignore_quota */
198 TRUE /* retry_include_ip_address */
200 ,NULL, /* tls_certificate */
202 NULL, /* tls_privatekey */
203 NULL, /* tls_require_ciphers */
204 NULL, /* gnutls_require_kx */
205 NULL, /* gnutls_require_mac */
206 NULL, /* gnutls_require_proto */
207 NULL, /* tls_verify_certificates */
208 TRUE /* tls_tempfail_tryclear */
210 #if (defined EXPERIMENTAL_DOMAINKEYS) || (defined EXPERIMENTAL_DKIM)
211 ,NULL, /* dk_canon */
212 NULL, /* dk_domain */
213 NULL, /* dk_headers */
214 NULL, /* dk_private_key */
215 NULL, /* dk_selector */
217 ,NULL, /* dkim_canon */
218 NULL, /* dkim_domain */
219 NULL, /* dkim_private_key */
220 NULL, /* dkim_selector */
221 NULL, /* dkim_sign_headers */
222 NULL /* dkim_strict */
229 static uschar *smtp_command; /* Points to last cmd for error messages */
230 static uschar *mail_command; /* Points to MAIL cmd for error messages */
231 static BOOL update_waiting; /* TRUE to update the "wait" database */
234 /*************************************************
235 * Setup entry point *
236 *************************************************/
238 /* This function is called when the transport is about to be used,
239 but before running it in a sub-process. It is used for two things:
241 (1) To set the fallback host list in addresses, when delivering.
242 (2) To pass back the interface, port, protocol, and other options, for use
243 during callout verification.
246 tblock pointer to the transport instance block
247 addrlist list of addresses about to be transported
248 tf if not NULL, pointer to block in which to return options
249 uid the uid that will be set (not used)
250 gid the gid that will be set (not used)
251 errmsg place for error message (not used)
253 Returns: OK always (FAIL, DEFER not used)
257 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
258 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
260 smtp_transport_options_block *ob =
261 (smtp_transport_options_block *)(tblock->options_block);
263 errmsg = errmsg; /* Keep picky compilers happy */
267 /* Pass back options if required. This interface is getting very messy. */
271 tf->interface = ob->interface;
273 tf->protocol = ob->protocol;
274 tf->hosts = ob->hosts;
275 tf->hosts_override = ob->hosts_override;
276 tf->hosts_randomize = ob->hosts_randomize;
277 tf->gethostbyname = ob->gethostbyname;
278 tf->qualify_single = ob->dns_qualify_single;
279 tf->search_parents = ob->dns_search_parents;
280 tf->helo_data = ob->helo_data;
283 /* Set the fallback host list for all the addresses that don't have fallback
284 host lists, provided that the local host wasn't present in the original host
287 if (!testflag(addrlist, af_local_host_removed))
289 for (; addrlist != NULL; addrlist = addrlist->next)
290 if (addrlist->fallback_hosts == NULL)
291 addrlist->fallback_hosts = ob->fallback_hostlist;
299 /*************************************************
300 * Initialization entry point *
301 *************************************************/
303 /* Called for each instance, after its options have been read, to
304 enable consistency checks to be done, or anything else that needs
307 Argument: pointer to the transport instance block
312 smtp_transport_init(transport_instance *tblock)
314 smtp_transport_options_block *ob =
315 (smtp_transport_options_block *)(tblock->options_block);
317 /* Retry_use_local_part defaults FALSE if unset */
319 if (tblock->retry_use_local_part == TRUE_UNSET)
320 tblock->retry_use_local_part = FALSE;
322 /* Set the default port according to the protocol */
324 if (ob->port == NULL)
325 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" : US"smtp";
327 /* Set up the setup entry point, to be called before subprocesses for this
330 tblock->setup = smtp_transport_setup;
332 /* Complain if any of the timeouts are zero. */
334 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
335 ob->final_timeout <= 0)
336 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
337 "command, data, or final timeout value is zero for %s transport",
340 /* If hosts_override is set and there are local hosts, set the global
341 flag that stops verify from showing router hosts. */
343 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
345 /* If there are any fallback hosts listed, build a chain of host items
346 for them, but do not do any lookups at this time. */
348 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
355 /*************************************************
356 * Set delivery info into all active addresses *
357 *************************************************/
359 /* Only addresses whose status is >= PENDING are relevant. A lesser
360 status means that an address is not currently being processed.
363 addrlist points to a chain of addresses
364 errno_value to put in each address's errno field
365 msg to put in each address's message field
366 rc to put in each address's transport_return field
367 pass_message if TRUE, set the "pass message" flag in the address
369 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
370 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
371 this particular type of timeout.
377 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
382 if (errno_value == ERRNO_CONNECTTIMEOUT)
384 errno_value = ETIMEDOUT;
385 orvalue = RTEF_CTOUT;
387 for (addr = addrlist; addr != NULL; addr = addr->next)
389 if (addr->transport_return < PENDING) continue;
390 addr->basic_errno = errno_value;
391 addr->more_errno |= orvalue;
395 if (pass_message) setflag(addr, af_pass_message);
397 addr->transport_return = rc;
403 /*************************************************
404 * Check an SMTP response *
405 *************************************************/
407 /* This function is given an errno code and the SMTP response buffer
408 to analyse, together with the host identification for generating messages. It
409 sets an appropriate message and puts the first digit of the response code into
410 the yield variable. If no response was actually read, a suitable digit is
414 host the current host, to get its name for messages
415 errno_value pointer to the errno value
416 more_errno from the top address for use with ERRNO_FILTER_FAIL
417 buffer the SMTP response buffer
418 yield where to put a one-digit SMTP response code
419 message where to put an errror message
420 pass_message set TRUE if message is an SMTP response
422 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
425 static BOOL check_response(host_item *host, int *errno_value, int more_errno,
426 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
430 if (smtp_use_pipelining &&
431 (Ustrcmp(smtp_command, "MAIL") == 0 ||
432 Ustrcmp(smtp_command, "RCPT") == 0 ||
433 Ustrcmp(smtp_command, "DATA") == 0))
436 *yield = '4'; /* Default setting is to give a temporary error */
438 /* Handle response timeout */
440 if (*errno_value == ETIMEDOUT)
442 *message = US string_sprintf("SMTP timeout while connected to %s [%s] "
443 "after %s%s", host->name, host->address, pl, smtp_command);
444 if (transport_count > 0)
445 *message = US string_sprintf("%s (%d bytes written)", *message,
450 /* Handle malformed SMTP response */
452 if (*errno_value == ERRNO_SMTPFORMAT)
454 uschar *malfresp = string_printing(buffer);
455 while (isspace(*malfresp)) malfresp++;
457 *message = string_sprintf("Malformed SMTP reply (an empty line) from "
458 "%s [%s] in response to %s%s", host->name, host->address, pl,
461 *message = string_sprintf("Malformed SMTP reply from %s [%s] in response "
462 "to %s%s: %s", host->name, host->address, pl, smtp_command, malfresp);
466 /* Handle a failed filter process error; can't send QUIT as we mustn't
469 if (*errno_value == ERRNO_FILTER_FAIL)
471 *message = US string_sprintf("transport filter process failed (%d)%s",
473 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
477 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
480 if (*errno_value == ERRNO_CHHEADER_FAIL)
483 US string_sprintf("failed to expand headers_add or headers_remove: %s",
484 expand_string_message);
488 /* Handle failure to write a complete data block */
490 if (*errno_value == ERRNO_WRITEINCOMPLETE)
492 *message = US string_sprintf("failed to write a data block");
496 /* Handle error responses from the remote mailer. */
500 uschar *s = string_printing(buffer);
501 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
502 "host %s [%s]: %s", pl, smtp_command, host->name, host->address, s);
503 *pass_message = TRUE;
508 /* No data was read. If there is no errno, this must be the EOF (i.e.
509 connection closed) case, which causes deferral. An explicit connection reset
510 error has the same effect. Otherwise, put the host's identity in the message,
511 leaving the errno value to be interpreted as well. In all cases, we have to
512 assume the connection is now dead. */
514 if (*errno_value == 0 || *errno_value == ECONNRESET)
516 *errno_value = ERRNO_SMTPCLOSED;
517 *message = US string_sprintf("Remote host %s [%s] closed connection "
518 "in response to %s%s", host->name, host->address, pl, smtp_command);
520 else *message = US string_sprintf("%s [%s]", host->name, host->address);
527 /*************************************************
528 * Write error message to logs *
529 *************************************************/
531 /* This writes to the main log and to the message log.
534 addr the address item containing error information
535 host the current host
541 write_logs(address_item *addr, host_item *host)
543 if (addr->message != NULL)
545 uschar *message = addr->message;
546 if (addr->basic_errno > 0)
547 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
548 log_write(0, LOG_MAIN, "%s", message);
549 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
554 ((log_extra_selector & LX_outgoing_port) != 0)?
555 string_sprintf("%s [%s]:%d", host->name, host->address,
556 (host->port == PORT_NONE)? 25 : host->port)
558 string_sprintf("%s [%s]", host->name, host->address);
559 log_write(0, LOG_MAIN, "%s %s", msg, strerror(addr->basic_errno));
560 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), msg,
561 strerror(addr->basic_errno));
567 /*************************************************
568 * Synchronize SMTP responses *
569 *************************************************/
571 /* This function is called from smtp_deliver() to receive SMTP responses from
572 the server, and match them up with the commands to which they relate. When
573 PIPELINING is not in use, this function is called after every command, and is
574 therefore somewhat over-engineered, but it is simpler to use a single scheme
575 that works both with and without PIPELINING instead of having two separate sets
578 The set of commands that are buffered up with pipelining may start with MAIL
579 and may end with DATA; in between are RCPT commands that correspond to the
580 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
581 etc.) are never buffered.
583 Errors after MAIL or DATA abort the whole process leaving the response in the
584 buffer. After MAIL, pending responses are flushed, and the original command is
585 re-instated in big_buffer for error messages. For RCPT commands, the remote is
586 permitted to reject some recipient addresses while accepting others. However
587 certain errors clearly abort the whole process. Set the value in
588 transport_return to PENDING_OK if the address is accepted. If there is a
589 subsequent general error, it will get reset accordingly. If not, it will get
590 converted to OK at the end.
593 addrlist the complete address list
594 include_affixes TRUE if affixes include in RCPT
595 sync_addr ptr to the ptr of the one to start scanning at (updated)
596 host the host we are connected to
597 count the number of responses to read
599 include_sender true if 4xx retry is to include the sender it its key
600 pending_MAIL true if the first response is for MAIL
601 pending_DATA 0 if last command sent was not DATA
602 +1 if previously had a good recipient
603 -1 if not previously had a good recipient
604 inblock incoming SMTP block
605 timeout timeout value
606 buffer buffer for reading response
607 buffsize size of buffer
609 Returns: 3 if at least one address had 2xx and one had 5xx
610 2 if at least one address had 5xx but none had 2xx
611 1 if at least one host had a 2xx response, but none had 5xx
612 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
613 -1 timeout while reading RCPT response
614 -2 I/O or other non-response error for RCPT
615 -3 DATA or MAIL failed - errno and buffer set
619 sync_responses(address_item *addrlist, BOOL include_affixes,
620 address_item **sync_addr, host_item *host, int count,
621 BOOL address_retry_include_sender, BOOL pending_MAIL,
622 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
625 address_item *addr = *sync_addr;
628 /* Handle the response for a MAIL command. On error, reinstate the original
629 command in big_buffer for error message use, and flush any further pending
630 responses before returning, except after I/O errors and timeouts. */
635 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
637 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
638 if (errno == 0 && buffer[0] != 0)
640 uschar flushbuffer[4096];
642 if (buffer[0] == '4')
644 save_errno = ERRNO_MAIL4XX;
645 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
649 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
651 && (errno != 0 || flushbuffer[0] == 0))
660 if (pending_DATA) count--; /* Number of RCPT responses to come */
662 /* Read and handle the required number of RCPT responses, matching each one up
663 with an address by scanning for the next address whose status is PENDING_DEFER.
668 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
670 /* The address was accepted */
672 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
675 addr->transport_return = PENDING_OK;
677 /* If af_dr_retry_exists is set, there was a routing delay on this address;
678 ensure that any address-specific retry record is expunged. We do this both
679 for the basic key and for the version that also includes the sender. */
681 if (testflag(addr, af_dr_retry_exists))
683 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
685 retry_add_item(addr, altkey, rf_delete);
686 retry_add_item(addr, addr->address_retry_key, rf_delete);
690 /* Timeout while reading the response */
692 else if (errno == ETIMEDOUT)
694 int save_errno = errno;
695 uschar *message = string_sprintf("SMTP timeout while connected to %s [%s] "
696 "after RCPT TO:<%s>", host->name, host->address,
697 transport_rcpt_address(addr, include_affixes));
698 set_errno(addrlist, save_errno, message, DEFER, FALSE);
699 retry_add_item(addr, addr->address_retry_key, 0);
700 update_waiting = FALSE;
704 /* Handle other errors in obtaining an SMTP response by returning -1. This
705 will cause all the addresses to be deferred. Restore the SMTP command in
706 big_buffer for which we are checking the response, so the error message
709 else if (errno != 0 || buffer[0] == 0)
711 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
712 transport_rcpt_address(addr, include_affixes));
716 /* Handle SMTP permanent and temporary response codes. */
721 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
722 "host %s [%s]: %s", transport_rcpt_address(addr, include_affixes),
723 host->name, host->address, string_printing(buffer));
724 setflag(addr, af_pass_message);
725 deliver_msglog("%s %s\n", tod_stamp(tod_log), addr->message);
727 /* The response was 5xx */
729 if (buffer[0] == '5')
731 addr->transport_return = FAIL;
735 /* The response was 4xx */
739 addr->transport_return = DEFER;
740 addr->basic_errno = ERRNO_RCPT4XX;
741 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
743 /* Log temporary errors if there are more hosts to be tried. */
745 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", addr->message);
747 /* Do not put this message on the list of those waiting for specific
748 hosts, as otherwise it is likely to be tried too often. */
750 update_waiting = FALSE;
752 /* Add a retry item for the address so that it doesn't get tried again
753 too soon. If address_retry_include_sender is true, add the sender address
756 if (address_retry_include_sender)
758 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
760 retry_add_item(addr, altkey, 0);
762 else retry_add_item(addr, addr->address_retry_key, 0);
765 } /* Loop for next RCPT response */
767 /* Update where to start at for the next block of responses, unless we
768 have already handled all the addresses. */
770 if (addr != NULL) *sync_addr = addr->next;
772 /* Handle a response to DATA. If we have not had any good recipients, either
773 previously or in this block, the response is ignored. */
775 if (pending_DATA != 0 &&
776 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
781 if (pending_DATA > 0 || (yield & 1) != 0)
783 if (errno == 0 && buffer[0] == '4')
785 errno = ERRNO_DATA4XX;
786 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
790 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
791 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
792 "is in use and there were no good recipients\n", msg);
795 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
796 present) received 3xx. If any RCPTs were handled and yielded anything other
797 than 4xx, yield will be set non-zero. */
804 /*************************************************
805 * Deliver address list to given host *
806 *************************************************/
808 /* If continue_hostname is not null, we get here only when continuing to
809 deliver down an existing channel. The channel was passed as the standard
810 input. TLS is never active on a passed channel; the previous process always
811 closes it down before passing the connection on.
813 Otherwise, we have to make a connection to the remote host, and do the
814 initial protocol exchange.
816 When running as an MUA wrapper, if the sender or any recipient is rejected,
817 temporarily or permanently, we force failure for all recipients.
820 addrlist chain of potential addresses to deliver; only those whose
821 transport_return field is set to PENDING_DEFER are currently
822 being processed; others should be skipped - they have either
823 been delivered to an earlier host or IP address, or been
824 failed by one of them.
825 host host to deliver to
826 host_af AF_INET or AF_INET6
827 port default TCP/IP port to use, in host byte order
828 interface interface to bind to, or NULL
829 tblock transport instance block
830 copy_host TRUE if host set in addr->host_used must be copied, because
831 it is specific to this call of the transport
832 message_defer set TRUE if yield is OK, but all addresses were deferred
833 because of a non-recipient, non-host failure, that is, a
834 4xx response to MAIL FROM, DATA, or ".". This is a defer
835 that is specific to the message.
836 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
837 a second attempt after TLS initialization fails
839 Returns: OK - the connection was made and the delivery attempted;
840 the result for each address is in its data block.
841 DEFER - the connection could not be made, or something failed
842 while setting up the SMTP session, or there was a
843 non-message-specific error, such as a timeout.
844 ERROR - a filter command is specified for this transport,
845 and there was a problem setting it up; OR helo_data
846 or add_headers or authenticated_sender is specified
847 for this transport, and the string failed to expand
851 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
852 uschar *interface, transport_instance *tblock, BOOL copy_host,
853 BOOL *message_defer, BOOL suppress_tls)
856 address_item *sync_addr;
857 address_item *first_addr = addrlist;
862 time_t start_delivery_time = time(NULL);
863 smtp_transport_options_block *ob =
864 (smtp_transport_options_block *)(tblock->options_block);
865 BOOL lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
867 BOOL send_rset = TRUE;
868 BOOL send_quit = TRUE;
869 BOOL setting_up = TRUE;
870 BOOL completed_address = FALSE;
873 BOOL pass_message = FALSE;
874 smtp_inblock inblock;
875 smtp_outblock outblock;
876 int max_rcpt = tblock->max_addresses;
877 uschar *igquotstr = US"";
878 uschar *local_authenticated_sender = authenticated_sender;
879 uschar *helo_data = NULL;
880 uschar *message = NULL;
881 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
884 uschar inbuffer[4096];
885 uschar outbuffer[1024];
887 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
889 *message_defer = FALSE;
890 smtp_command = US"initial connection";
891 if (max_rcpt == 0) max_rcpt = 999999;
893 /* Set up the buffer for reading SMTP response packets. */
895 inblock.buffer = inbuffer;
896 inblock.buffersize = sizeof(inbuffer);
897 inblock.ptr = inbuffer;
898 inblock.ptrend = inbuffer;
900 /* Set up the buffer for holding SMTP commands while pipelining */
902 outblock.buffer = outbuffer;
903 outblock.buffersize = sizeof(outbuffer);
904 outblock.ptr = outbuffer;
905 outblock.cmd_count = 0;
906 outblock.authenticating = FALSE;
908 /* Reset the parameters of a TLS session. */
913 /* If an authenticated_sender override has been specified for this transport
914 instance, expand it. If the expansion is forced to fail, and there was already
915 an authenticated_sender for this message, the original value will be used.
916 Other expansion failures are serious. An empty result is ignored, but there is
917 otherwise no check - this feature is expected to be used with LMTP and other
918 cases where non-standard addresses (e.g. without domains) might be required. */
920 if (ob->authenticated_sender != NULL)
922 uschar *new = expand_string(ob->authenticated_sender);
925 if (!expand_string_forcedfail)
927 uschar *message = string_sprintf("failed to expand "
928 "authenticated_sender: %s", expand_string_message);
929 set_errno(addrlist, 0, message, DEFER, FALSE);
933 else if (new[0] != 0) local_authenticated_sender = new;
936 /* Make a connection to the host if this isn't a continued delivery, and handle
937 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
938 specially so they can be identified for retries. */
940 if (continue_hostname == NULL)
942 inblock.sock = outblock.sock =
943 smtp_connect(host, host_af, port, interface, ob->connect_timeout,
944 ob->keepalive); /* This puts port into host->port */
946 if (inblock.sock < 0)
948 set_errno(addrlist, (errno == ETIMEDOUT)? ERRNO_CONNECTTIMEOUT : errno,
953 /* Expand the greeting message while waiting for the initial response. (Makes
954 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
955 delayed till here so that $sending_interface and $sending_port are set. */
957 helo_data = expand_string(ob->helo_data);
959 /* The first thing is to wait for an initial OK response. The dreaded "goto"
960 is nevertheless a reasonably clean way of programming this kind of logic,
961 where you want to escape on any error. */
963 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
964 ob->command_timeout)) goto RESPONSE_FAILED;
966 /* Now check if the helo_data expansion went well, and sign off cleanly if it
969 if (helo_data == NULL)
971 uschar *message = string_sprintf("failed to expand helo_data: %s",
972 expand_string_message);
973 set_errno(addrlist, 0, message, DEFER, FALSE);
978 /** Debugging without sending a message
979 addrlist->transport_return = DEFER;
983 /* Errors that occur after this point follow an SMTP command, which is
984 left in big_buffer by smtp_write_command() for use in error messages. */
986 smtp_command = big_buffer;
988 /* Tell the remote who we are...
990 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
991 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
992 greeting is of this form. The assumption was that the far end supports it
993 properly... but experience shows that there are some that give 5xx responses,
994 even though the banner includes "ESMTP" (there's a bloody-minded one that
995 says "ESMTP not spoken here"). Cope with that case.
997 September 2000: Time has passed, and it seems reasonable now to always send
998 EHLO at the start. It is also convenient to make the change while installing
1001 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1002 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1003 would be no way to send out the mails, so there is now a host list
1004 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1005 PIPELINING problem as well. Maybe it can also be useful to cure other
1006 problems with broken servers.
1008 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1009 Then somebody tried it with a Microsoft mailer... It seems that all other
1010 mailers use upper case for some reason (the RFC is quite clear about case
1011 independence) so, for peace of mind, I gave in. */
1013 esmtp = verify_check_this_host(&(ob->hosts_avoid_esmtp), NULL,
1014 host->name, host->address, NULL) != OK;
1018 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1019 lmtp? "LHLO" : "EHLO", helo_data) < 0)
1021 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1022 ob->command_timeout))
1024 if (errno != 0 || buffer[0] == 0 || lmtp) goto RESPONSE_FAILED;
1031 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1036 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1038 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1039 ob->command_timeout)) goto RESPONSE_FAILED;
1042 /* Set IGNOREQUOTA if the response to LHLO specifies support and the
1043 lmtp_ignore_quota option was set. */
1045 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1046 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1047 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1049 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1052 tls_offered = esmtp &&
1053 pcre_exec(regex_STARTTLS, NULL, CS buffer, Ustrlen(buffer), 0,
1054 PCRE_EOPT, NULL, 0) >= 0;
1058 /* For continuing deliveries down the same channel, the socket is the standard
1059 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1060 below). Set up the pointer to where subsequent commands will be left, for
1061 error messages. Note that smtp_use_size and smtp_use_pipelining will have been
1062 set from the command line if they were set in the process that passed the
1067 inblock.sock = outblock.sock = fileno(stdin);
1068 smtp_command = big_buffer;
1069 host->port = port; /* Record the port that was used */
1072 /* If TLS is available on this connection, whether continued or not, attempt to
1073 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1074 send another EHLO - the server may give a different answer in secure mode. We
1075 use a separate buffer for reading the response to STARTTLS so that if it is
1076 negative, the original EHLO data is available for subsequent analysis, should
1077 the client not be required to use TLS. If the response is bad, copy the buffer
1078 for error analysis. */
1081 if (tls_offered && !suppress_tls &&
1082 verify_check_this_host(&(ob->hosts_avoid_tls), NULL, host->name,
1083 host->address, NULL) != OK)
1085 uschar buffer2[4096];
1086 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1089 /* If there is an I/O error, transmission of this message is deferred. If
1090 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1091 false, we also defer. However, if there is a temporary rejection of STARTTLS
1092 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1093 STARTTLS, we carry on. This means we will try to send the message in clear,
1094 unless the host is in hosts_require_tls (tested below). */
1096 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1097 ob->command_timeout))
1099 Ustrncpy(buffer, buffer2, sizeof(buffer));
1100 if (errno != 0 || buffer2[0] == 0 ||
1101 (buffer2[0] == '4' && !ob->tls_tempfail_tryclear))
1102 goto RESPONSE_FAILED;
1105 /* STARTTLS accepted: try to negotiate a TLS session. */
1109 int rc = tls_client_start(inblock.sock,
1112 NULL, /* No DH param */
1113 ob->tls_certificate,
1115 ob->tls_verify_certificates,
1117 ob->tls_require_ciphers,
1118 ob->gnutls_require_mac,
1119 ob->gnutls_require_kx,
1120 ob->gnutls_require_proto,
1121 ob->command_timeout);
1123 /* TLS negotiation failed; give an error. From outside, this function may
1124 be called again to try in clear on a new connection, if the options permit
1125 it for this host. */
1129 save_errno = ERRNO_TLSFAILURE;
1130 message = US"failure while setting up TLS session";
1135 /* TLS session is set up */
1137 for (addr = addrlist; addr != NULL; addr = addr->next)
1139 if (addr->transport_return == PENDING_DEFER)
1141 addr->cipher = tls_cipher;
1142 addr->peerdn = tls_peerdn;
1148 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1149 helo_data is null, we are dealing with a connection that was passed from
1150 another process, and so we won't have expanded helo_data above. We have to
1151 expand it here. $sending_ip_address and $sending_port are set up right at the
1152 start of the Exim process (in exim.c). */
1154 if (tls_active >= 0)
1156 if (helo_data == NULL)
1158 helo_data = expand_string(ob->helo_data);
1159 if (helo_data == NULL)
1161 uschar *message = string_sprintf("failed to expand helo_data: %s",
1162 expand_string_message);
1163 set_errno(addrlist, 0, message, DEFER, FALSE);
1169 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n", lmtp? "LHLO" : "EHLO",
1172 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1173 ob->command_timeout))
1174 goto RESPONSE_FAILED;
1177 /* If the host is required to use a secure channel, ensure that we
1180 else if (verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
1181 host->address, NULL) == OK)
1183 save_errno = ERRNO_TLSREQUIRED;
1184 message = string_sprintf("a TLS session is required for %s [%s], but %s",
1185 host->name, host->address,
1186 tls_offered? "an attempt to start TLS failed" :
1187 "the server did not offer TLS support");
1192 /* If TLS is active, we have just started it up and re-done the EHLO command,
1193 so its response needs to be analyzed. If TLS is not active and this is a
1194 continued session down a previously-used socket, we haven't just done EHLO, so
1197 if (continue_hostname == NULL
1204 uschar *fail_reason = US"server did not advertise AUTH support";
1206 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
1207 lmtp_ignore_quota option was set. */
1209 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1210 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1211 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1213 /* If the response to EHLO specified support for the SIZE parameter, note
1214 this, provided size_addition is non-negative. */
1216 smtp_use_size = esmtp && ob->size_addition >= 0 &&
1217 pcre_exec(regex_SIZE, NULL, CS buffer, Ustrlen(CS buffer), 0,
1218 PCRE_EOPT, NULL, 0) >= 0;
1220 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
1221 the current host, esmtp will be false, so PIPELINING can never be used. If
1222 the current host matches hosts_avoid_pipelining, don't do it. */
1224 smtp_use_pipelining = esmtp &&
1225 verify_check_this_host(&(ob->hosts_avoid_pipelining), NULL, host->name,
1226 host->address, NULL) != OK &&
1227 pcre_exec(regex_PIPELINING, NULL, CS buffer, Ustrlen(CS buffer), 0,
1228 PCRE_EOPT, NULL, 0) >= 0;
1230 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
1231 smtp_use_pipelining? "" : "not ");
1233 /* Note if the response to EHLO specifies support for the AUTH extension.
1234 If it has, check that this host is one we want to authenticate to, and do
1235 the business. The host name and address must be available when the
1236 authenticator's client driver is running. */
1238 smtp_authenticated = FALSE;
1239 require_auth = verify_check_this_host(&(ob->hosts_require_auth), NULL,
1240 host->name, host->address, NULL);
1242 if (esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
1244 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
1245 expand_nmax = -1; /* reset */
1247 /* Must not do this check until after we have saved the result of the
1248 regex match above. */
1250 if (require_auth == OK ||
1251 verify_check_this_host(&(ob->hosts_try_auth), NULL, host->name,
1252 host->address, NULL) == OK)
1255 fail_reason = US"no common mechanisms were found";
1257 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1259 /* Scan the configured authenticators looking for one which is configured
1260 for use as a client, which is not suppressed by client_condition, and
1261 whose name matches an authentication mechanism supported by the server.
1262 If one is found, attempt to authenticate by calling its client function.
1265 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1269 (au->client_condition != NULL &&
1270 !expand_check_condition(au->client_condition, au->name,
1271 US"client authenticator")))
1273 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1275 (au->client)? "client_condition is false" :
1276 "not configured as a client");
1280 /* Loop to scan supported server mechanisms */
1285 int len = Ustrlen(au->public_name);
1286 while (isspace(*p)) p++;
1288 if (strncmpic(au->public_name, p, len) != 0 ||
1289 (p[len] != 0 && !isspace(p[len])))
1291 while (*p != 0 && !isspace(*p)) p++;
1295 /* Found data for a listed mechanism. Call its client entry. Set
1296 a flag in the outblock so that data is overwritten after sending so
1297 that reflections don't show it. */
1299 fail_reason = US"authentication attempt(s) failed";
1300 outblock.authenticating = TRUE;
1301 rc = (au->info->clientcode)(au, &inblock, &outblock,
1302 ob->command_timeout, buffer, sizeof(buffer));
1303 outblock.authenticating = FALSE;
1304 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1307 /* A temporary authentication failure must hold up delivery to
1308 this host. After a permanent authentication failure, we carry on
1309 to try other authentication methods. If all fail hard, try to
1310 deliver the message unauthenticated unless require_auth was set. */
1315 smtp_authenticated = TRUE; /* stops the outer loop */
1318 /* Failure after writing a command */
1323 /* Failure after reading a response */
1326 if (errno != 0 || buffer[0] != '5') goto RESPONSE_FAILED;
1327 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1328 au->name, host->name, host->address, buffer);
1331 /* Failure by some other means. In effect, the authenticator
1332 decided it wasn't prepared to handle this case. Typically this
1333 is the result of "fail" in an expansion string. Do we need to
1334 log anything here? Feb 2006: a message is now put in the buffer
1335 if logging is required. */
1339 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1340 "authentication H=%s [%s] %s", au->name, host->name,
1341 host->address, buffer);
1344 /* Internal problem, message in buffer. */
1348 set_errno(addrlist, 0, string_copy(buffer), DEFER, FALSE);
1352 break; /* If not authenticated, try next authenticator */
1353 } /* Loop for scanning supported server mechanisms */
1354 } /* Loop for further authenticators */
1358 /* If we haven't authenticated, but are required to, give up. */
1360 if (require_auth == OK && !smtp_authenticated)
1363 set_errno(addrlist, ERRNO_AUTHFAIL,
1364 string_sprintf("authentication required but %s", fail_reason), DEFER,
1370 /* The setting up of the SMTP call is now complete. Any subsequent errors are
1371 message-specific. */
1375 /* If there is a filter command specified for this transport, we can now
1376 set it up. This cannot be done until the identify of the host is known. */
1378 if (tblock->filter_command != NULL)
1382 sprintf(CS buffer, "%.50s transport", tblock->name);
1383 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
1384 TRUE, DEFER, addrlist, buffer, NULL);
1385 transport_filter_timeout = tblock->filter_timeout;
1387 /* On failure, copy the error to all addresses, abandon the SMTP call, and
1392 set_errno(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
1400 /* For messages that have more than the maximum number of envelope recipients,
1401 we want to send several transactions down the same SMTP connection. (See
1402 comments in deliver.c as to how this reconciles, heuristically, with
1403 remote_max_parallel.) This optimization was added to Exim after the following
1404 code was already working. The simplest way to put it in without disturbing the
1405 code was to use a goto to jump back to this point when there is another
1406 transaction to handle. */
1409 sync_addr = first_addr;
1413 completed_address = FALSE;
1416 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
1417 qualification, send it, adding something to the message size to allow for
1418 imprecision and things that get added en route. Exim keeps the number of lines
1419 in a message, so we can give an accurate value for the original message, but we
1420 need some additional to handle added headers. (Double "." characters don't get
1421 included in the count.) */
1428 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
1432 /* Add the authenticated sender address if present */
1434 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1435 local_authenticated_sender != NULL)
1437 string_format(p, sizeof(buffer) - (p-buffer), " AUTH=%s",
1438 auth_xtextencode(local_authenticated_sender,
1439 Ustrlen(local_authenticated_sender)));
1442 /* From here until we send the DATA command, we can make use of PIPELINING
1443 if the server host supports it. The code has to be able to check the responses
1444 at any point, for when the buffer fills up, so we write it totally generally.
1445 When PIPELINING is off, each command written reports that it has flushed the
1448 pending_MAIL = TRUE; /* The block starts with MAIL */
1450 rc = smtp_write_command(&outblock, smtp_use_pipelining,
1451 "MAIL FROM:<%s>%s\r\n", return_path, buffer);
1452 mail_command = string_copy(big_buffer); /* Save for later error message */
1456 case -1: /* Transmission error */
1459 case +1: /* Block was sent */
1460 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1461 ob->command_timeout))
1463 if (errno == 0 && buffer[0] == '4')
1465 errno = ERRNO_MAIL4XX;
1466 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1468 goto RESPONSE_FAILED;
1470 pending_MAIL = FALSE;
1474 /* Pass over all the relevant recipient addresses for this host, which are the
1475 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
1476 several before we have to read the responses for those seen so far. This
1477 checking is done by a subroutine because it also needs to be done at the end.
1478 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
1479 the next one if not all are sent.
1481 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
1482 last address because we want to abort if any recipients have any kind of
1483 problem, temporary or permanent. We know that all recipient addresses will have
1484 the PENDING_DEFER status, because only one attempt is ever made, and we know
1485 that max_rcpt will be large, so all addresses will be done at once. */
1487 for (addr = first_addr;
1488 address_count < max_rcpt && addr != NULL;
1494 if (addr->transport_return != PENDING_DEFER) continue;
1497 no_flush = smtp_use_pipelining && (!mua_wrapper || addr->next != NULL);
1499 /* Now send the RCPT command, and process outstanding responses when
1500 necessary. After a timeout on RCPT, we just end the function, leaving the
1501 yield as OK, because this error can often mean that there is a problem with
1502 just one address, so we don't want to delay the host. */
1504 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s\r\n",
1505 transport_rcpt_address(addr, tblock->rcpt_include_affixes), igquotstr);
1506 if (count < 0) goto SEND_FAILED;
1509 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
1510 &sync_addr, host, count, ob->address_retry_include_sender,
1511 pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
1514 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1515 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1518 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1519 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1520 case 0: /* No 2xx or 5xx, but no probs */
1523 case -1: goto END_OFF; /* Timeout on RCPT */
1524 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
1526 pending_MAIL = FALSE; /* Dealt with MAIL */
1528 } /* Loop for next address */
1530 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
1531 permanently or temporarily. We should have flushed and synced after the last
1536 address_item *badaddr;
1537 for (badaddr = first_addr; badaddr != NULL; badaddr = badaddr->next)
1539 if (badaddr->transport_return != PENDING_OK) break;
1541 if (badaddr != NULL)
1543 set_errno(addrlist, 0, badaddr->message, FAIL,
1544 testflag(badaddr, af_pass_message));
1549 /* If ok is TRUE, we know we have got at least one good recipient, and must now
1550 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
1551 have a good recipient buffered up if we are pipelining. We don't want to waste
1552 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
1553 are pipelining. The responses are all handled by sync_responses(). */
1555 if (ok || (smtp_use_pipelining && !mua_wrapper))
1557 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
1558 if (count < 0) goto SEND_FAILED;
1559 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
1560 host, count, ob->address_retry_include_sender, pending_MAIL,
1561 ok? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
1563 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1564 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1567 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1568 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1569 case 0: break; /* No 2xx or 5xx, but no probs */
1571 case -1: goto END_OFF; /* Timeout on RCPT */
1572 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
1576 /* Save the first address of the next batch. */
1580 /* If there were no good recipients (but otherwise there have been no
1581 problems), just set ok TRUE, since we have handled address-specific errors
1582 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
1583 for handling the SMTP dot-handling protocol, flagging to apply to headers as
1584 well as body. Set the appropriate timeout value to be used for each chunk.
1585 (Haven't been able to make it work using select() for writing yet.) */
1587 if (!ok) ok = TRUE; else
1589 sigalrm_seen = FALSE;
1590 transport_write_timeout = ob->data_timeout;
1591 smtp_command = US"sending data block"; /* For error messages */
1592 DEBUG(D_transport|D_v)
1593 debug_printf(" SMTP>> writing message and terminating \".\"\n");
1594 transport_count = 0;
1595 #if (defined EXPERIMENTAL_DOMAINKEYS) || (defined EXPERIMENTAL_DKIM)
1596 ok = dkim_transport_write_message(addrlist, inblock.sock,
1597 topt_use_crlf | topt_end_dot | topt_escape_headers |
1598 (tblock->body_only? topt_no_headers : 0) |
1599 (tblock->headers_only? topt_no_body : 0) |
1600 (tblock->return_path_add? topt_add_return_path : 0) |
1601 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1602 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1603 0, /* No size limit */
1604 tblock->add_headers, tblock->remove_headers,
1605 US".", US"..", /* Escaping strings */
1606 tblock->rewrite_rules, tblock->rewrite_existflags,
1607 ob->dkim_private_key, ob->dkim_domain, ob->dkim_selector,
1608 ob->dkim_canon, ob->dkim_strict, ob->dkim_sign_headers,
1609 ob->dk_private_key, ob->dk_domain, ob->dk_selector,
1610 ob->dk_canon, ob->dk_headers, ob->dk_strict
1613 ok = transport_write_message(addrlist, inblock.sock,
1614 topt_use_crlf | topt_end_dot | topt_escape_headers |
1615 (tblock->body_only? topt_no_headers : 0) |
1616 (tblock->headers_only? topt_no_body : 0) |
1617 (tblock->return_path_add? topt_add_return_path : 0) |
1618 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1619 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1620 0, /* No size limit */
1621 tblock->add_headers, tblock->remove_headers,
1622 US".", US"..", /* Escaping strings */
1623 tblock->rewrite_rules, tblock->rewrite_existflags);
1626 /* transport_write_message() uses write() because it is called from other
1627 places to write to non-sockets. This means that under some OS (e.g. Solaris)
1628 it can exit with "Broken pipe" as its error. This really means that the
1629 socket got closed at the far end. */
1631 transport_write_timeout = 0; /* for subsequent transports */
1633 /* Failure can either be some kind of I/O disaster (including timeout),
1634 or the failure of a transport filter or the expansion of added headers. */
1638 buffer[0] = 0; /* There hasn't been a response */
1639 goto RESPONSE_FAILED;
1642 /* We used to send the terminating "." explicitly here, but because of
1643 buffering effects at both ends of TCP/IP connections, you don't gain
1644 anything by keeping it separate, so it might as well go in the final
1645 data buffer for efficiency. This is now done by setting the topt_end_dot
1648 smtp_command = US"end of data";
1650 /* For SMTP, we now read a single response that applies to the whole message.
1651 If it is OK, then all the addresses have been delivered. */
1655 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1657 if (!ok && errno == 0 && buffer[0] == '4')
1659 errno = ERRNO_DATA4XX;
1660 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1664 /* For LMTP, we get back a response for every RCPT command that we sent;
1665 some may be accepted and some rejected. For those that get a response, their
1666 status is fixed; any that are accepted have been handed over, even if later
1667 responses crash - at least, that's how I read RFC 2033.
1669 If all went well, mark the recipient addresses as completed, record which
1670 host/IPaddress they were delivered to, and cut out RSET when sending another
1671 message down the same channel. Write the completed addresses to the journal
1672 now so that they are recorded in case there is a crash of hardware or
1673 software before the spool gets updated. Also record the final SMTP
1674 confirmation if needed (for SMTP only). */
1679 int delivery_time = (int)(time(NULL) - start_delivery_time);
1682 uschar *conf = NULL;
1685 /* Make a copy of the host if it is local to this invocation
1686 of the transport. */
1690 thost = store_get(sizeof(host_item));
1692 thost->name = string_copy(host->name);
1693 thost->address = string_copy(host->address);
1697 /* Set up confirmation if needed - applies only to SMTP */
1699 if ((log_extra_selector & LX_smtp_confirmation) != 0 && !lmtp)
1701 uschar *s = string_printing(buffer);
1702 conf = (s == buffer)? (uschar *)string_copy(s) : s;
1705 /* Process all transported addresses - for LMTP, read a status for
1708 for (addr = addrlist; addr != first_addr; addr = addr->next)
1710 if (addr->transport_return != PENDING_OK) continue;
1712 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
1713 remaining addresses. Otherwise, it's a return code for just the one
1714 address. For temporary errors, add a retry item for the address so that
1715 it doesn't get tried again too soon. */
1719 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1722 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
1723 addr->message = string_sprintf("LMTP error after %s: %s",
1724 big_buffer, string_printing(buffer));
1725 setflag(addr, af_pass_message); /* Allow message to go to user */
1726 if (buffer[0] == '5')
1727 addr->transport_return = FAIL;
1730 errno = ERRNO_DATA4XX;
1731 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1732 addr->transport_return = DEFER;
1733 retry_add_item(addr, addr->address_retry_key, 0);
1737 completed_address = TRUE; /* NOW we can set this flag */
1740 /* SMTP, or success return from LMTP for this address. Pass back the
1741 actual host that was used. */
1743 addr->transport_return = OK;
1744 addr->more_errno = delivery_time;
1745 addr->host_used = thost;
1746 addr->special_action = flag;
1747 addr->message = conf;
1750 /* Update the journal. For homonymic addresses, use the base address plus
1751 the transport name. See lots of comments in deliver.c about the reasons
1752 for the complications when homonyms are involved. Just carry on after
1753 write error, as it may prove possible to update the spool file later. */
1755 if (testflag(addr, af_homonym))
1756 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
1758 sprintf(CS buffer, "%.500s\n", addr->unique);
1760 DEBUG(D_deliver) debug_printf("journalling %s", buffer);
1761 len = Ustrlen(CS buffer);
1762 if (write(journal_fd, buffer, len) != len)
1763 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
1764 "%s: %s", buffer, strerror(errno));
1767 /* Ensure the journal file is pushed out to disk. */
1769 if (EXIMfsync(journal_fd) < 0)
1770 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
1776 /* Handle general (not specific to one address) failures here. The value of ok
1777 is used to skip over this code on the falling through case. A timeout causes a
1778 deferral. Other errors may defer or fail according to the response code, and
1779 may set up a special errno value, e.g. after connection chopped, which is
1780 assumed if errno == 0 and there is no text in the buffer. If control reaches
1781 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
1782 the problem is not related to this specific message. */
1791 send_quit = check_response(host, &save_errno, addrlist->more_errno,
1792 buffer, &code, &message, &pass_message);
1798 message = US string_sprintf("send() to %s [%s] failed: %s",
1799 host->name, host->address, strerror(save_errno));
1803 /* This label is jumped to directly when a TLS negotiation has failed,
1804 or was not done for a host for which it is required. Values will be set
1805 in message and save_errno, and setting_up will always be true. Treat as
1806 a temporary error. */
1813 /* If the failure happened while setting up the call, see if the failure was
1814 a 5xx response (this will either be on connection, or following HELO - a 5xx
1815 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
1816 never going to accept them. For other errors during setting up (timeouts or
1817 whatever), defer all addresses, and yield DEFER, so that the host is not
1818 tried again for a while. */
1821 ok = FALSE; /* For when reached by GOTO */
1827 set_errno(addrlist, save_errno, message, FAIL, pass_message);
1831 set_errno(addrlist, save_errno, message, DEFER, pass_message);
1836 /* We want to handle timeouts after MAIL or "." and loss of connection after
1837 "." specially. They can indicate a problem with the sender address or with
1838 the contents of the message rather than a real error on the connection. These
1839 cases are treated in the same way as a 4xx response. This next bit of code
1840 does the classification. */
1851 message_error = TRUE;
1855 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
1856 Ustrncmp(smtp_command,"end ",4) == 0;
1859 case ERRNO_SMTPCLOSED:
1860 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
1864 message_error = FALSE;
1868 /* Handle the cases that are treated as message errors. These are:
1870 (a) negative response or timeout after MAIL
1871 (b) negative response after DATA
1872 (c) negative response or timeout or dropped connection after "."
1874 It won't be a negative response or timeout after RCPT, as that is dealt
1875 with separately above. The action in all cases is to set an appropriate
1876 error code for all the addresses, but to leave yield set to OK because the
1877 host itself has not failed. Of course, it might in practice have failed
1878 when we've had a timeout, but if so, we'll discover that at the next
1879 delivery attempt. For a temporary error, set the message_defer flag, and
1880 write to the logs for information if this is not the last host. The error
1881 for the last host will be logged as part of the address's log line. */
1885 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
1886 set_errno(addrlist, save_errno, message, (code == '5')? FAIL : DEFER,
1889 /* If there's an errno, the message contains just the identity of
1892 if (code != '5') /* Anything other than 5 is treated as temporary */
1895 message = US string_sprintf("%s: %s", message, strerror(save_errno));
1896 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
1897 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
1898 *message_defer = TRUE;
1902 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
1903 ".", or some other transportation error. We defer all addresses and yield
1904 DEFER, except for the case of failed add_headers expansion, or a transport
1905 filter failure, when the yield should be ERROR, to stop it trying other
1910 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
1911 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
1912 set_errno(addrlist, save_errno, message, DEFER, pass_message);
1918 /* If all has gone well, send_quit will be set TRUE, implying we can end the
1919 SMTP session tidily. However, if there were too many addresses to send in one
1920 message (indicated by first_addr being non-NULL) we want to carry on with the
1921 rest of them. Also, it is desirable to send more than one message down the SMTP
1922 connection if there are several waiting, provided we haven't already sent so
1923 many as to hit the configured limit. The function transport_check_waiting looks
1924 for a waiting message and returns its id. Then transport_pass_socket tries to
1925 set up a continued delivery by passing the socket on to another process. The
1926 variable send_rset is FALSE if a message has just been successfully transfered.
1928 If we are already sending down a continued channel, there may be further
1929 addresses not yet delivered that are aimed at the same host, but which have not
1930 been passed in this run of the transport. In this case, continue_more will be
1931 true, and all we should do is send RSET if necessary, and return, leaving the
1934 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
1935 do not want to continue with other messages down the same channel, because that
1936 can lead to looping between two or more messages, all with the same,
1937 temporarily failing address(es). [The retry information isn't updated yet, so
1938 new processes keep on trying.] We probably also don't want to try more of this
1939 message's addresses either.
1941 If we have started a TLS session, we have to end it before passing the
1942 connection to a new process. However, not all servers can handle this (Exim
1943 can), so we do not pass such a connection on if the host matches
1944 hosts_nopass_tls. */
1947 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
1948 "yield=%d first_address is %sNULL\n", ok, send_quit, send_rset,
1949 continue_more, yield, (first_addr == NULL)? "":"not ");
1951 if (completed_address && ok && send_quit)
1954 if (first_addr != NULL || continue_more ||
1957 verify_check_this_host(&(ob->hosts_nopass_tls), NULL, host->name,
1958 host->address, NULL) != OK)
1960 transport_check_waiting(tblock->name, host->name,
1961 tblock->connection_max_messages, new_message_id, &more)
1969 if (! (ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
1971 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
1972 host->address, strerror(save_errno));
1975 else if (! (ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1976 ob->command_timeout)))
1979 send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
1983 DEBUG(D_transport) debug_printf("%s\n", msg);
1988 /* Either RSET was not needed, or it succeeded */
1992 if (first_addr != NULL) /* More addresses still to be sent */
1993 { /* in this run of the transport */
1994 continue_sequence++; /* Causes * in logging */
1997 if (continue_more) return yield; /* More addresses for another run */
1999 /* Pass the socket to a new Exim process. Before doing so, we must shut
2000 down TLS. Not all MTAs allow for the continuation of the SMTP session
2001 when TLS is shut down. We test for this by sending a new EHLO. If we
2002 don't get a good response, we don't attempt to pass the socket on. */
2005 if (tls_active >= 0)
2008 ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
2009 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2010 ob->command_timeout);
2014 /* If the socket is successfully passed, we musn't send QUIT (or
2015 indeed anything!) from here. */
2017 if (ok && transport_pass_socket(tblock->name, host->name, host->address,
2018 new_message_id, inblock.sock))
2024 /* If RSET failed and there are addresses left, they get deferred. */
2026 else set_errno(first_addr, errno, msg, DEFER, FALSE);
2030 /* End off tidily with QUIT unless the connection has died or the socket has
2031 been passed to another process. There has been discussion on the net about what
2032 to do after sending QUIT. The wording of the RFC suggests that it is necessary
2033 to wait for a response, but on the other hand, there isn't anything one can do
2034 with an error response, other than log it. Exim used to do that. However,
2035 further discussion suggested that it is positively advantageous not to wait for
2036 the response, but to close the session immediately. This is supposed to move
2037 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
2038 load from the server. (Hosts that are both servers and clients may not see much
2039 difference, of course.) Further discussion indicated that this was safe to do
2040 on Unix systems which have decent implementations of TCP/IP that leave the
2041 connection around for a while (TIME_WAIT) after the application has gone away.
2042 This enables the response sent by the server to be properly ACKed rather than
2043 timed out, as can happen on broken TCP/IP implementations on other OS.
2045 This change is being made on 31-Jul-98. After over a year of trouble-free
2046 operation, the old commented-out code was removed on 17-Sep-99. */
2049 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2057 /* Close the socket, and return the appropriate value, first setting
2058 continue_transport and continue_hostname NULL to prevent any other addresses
2059 that may include the host from trying to re-use a continuation socket. This
2060 works because the NULL setting is passed back to the calling process, and
2061 remote_max_parallel is forced to 1 when delivering over an existing connection,
2063 If all went well and continue_more is set, we shouldn't actually get here if
2064 there are further addresses, as the return above will be taken. However,
2065 writing RSET might have failed, or there may be other addresses whose hosts are
2066 specified in the transports, and therefore not visible at top level, in which
2067 case continue_more won't get set. */
2069 (void)close(inblock.sock);
2070 continue_transport = NULL;
2071 continue_hostname = NULL;
2078 /*************************************************
2079 * Closedown entry point *
2080 *************************************************/
2082 /* This function is called when exim is passed an open smtp channel
2083 from another incarnation, but the message which it has been asked
2084 to deliver no longer exists. The channel is on stdin.
2086 We might do fancy things like looking for another message to send down
2087 the channel, but if the one we sought has gone, it has probably been
2088 delivered by some other process that itself will seek further messages,
2089 so just close down our connection.
2091 Argument: pointer to the transport instance block
2096 smtp_transport_closedown(transport_instance *tblock)
2098 smtp_transport_options_block *ob =
2099 (smtp_transport_options_block *)(tblock->options_block);
2100 smtp_inblock inblock;
2101 smtp_outblock outblock;
2103 uschar inbuffer[4096];
2104 uschar outbuffer[16];
2106 inblock.sock = fileno(stdin);
2107 inblock.buffer = inbuffer;
2108 inblock.buffersize = sizeof(inbuffer);
2109 inblock.ptr = inbuffer;
2110 inblock.ptrend = inbuffer;
2112 outblock.sock = inblock.sock;
2113 outblock.buffersize = sizeof(outbuffer);
2114 outblock.buffer = outbuffer;
2115 outblock.ptr = outbuffer;
2116 outblock.cmd_count = 0;
2117 outblock.authenticating = FALSE;
2119 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2120 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2121 ob->command_timeout);
2122 (void)close(inblock.sock);
2127 /*************************************************
2128 * Prepare addresses for delivery *
2129 *************************************************/
2131 /* This function is called to flush out error settings from previous delivery
2132 attempts to other hosts. It also records whether we got here via an MX record
2133 or not in the more_errno field of the address. We are interested only in
2134 addresses that are still marked DEFER - others may have got delivered to a
2135 previously considered IP address. Set their status to PENDING_DEFER to indicate
2136 which ones are relevant this time.
2139 addrlist the list of addresses
2140 host the host we are delivering to
2142 Returns: the first address for this delivery
2145 static address_item *
2146 prepare_addresses(address_item *addrlist, host_item *host)
2148 address_item *first_addr = NULL;
2150 for (addr = addrlist; addr != NULL; addr = addr->next)
2152 if (addr->transport_return != DEFER) continue;
2153 if (first_addr == NULL) first_addr = addr;
2154 addr->transport_return = PENDING_DEFER;
2155 addr->basic_errno = 0;
2156 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
2157 addr->message = NULL;
2159 addr->cipher = NULL;
2160 addr->peerdn = NULL;
2168 /*************************************************
2169 * Main entry point *
2170 *************************************************/
2172 /* See local README for interface details. As this is a remote transport, it is
2173 given a chain of addresses to be delivered in one connection, if possible. It
2174 always returns TRUE, indicating that each address has its own independent
2175 status set, except if there is a setting up problem, in which case it returns
2179 smtp_transport_entry(
2180 transport_instance *tblock, /* data for this instantiation */
2181 address_item *addrlist) /* addresses we are working on */
2185 int hosts_defer = 0;
2187 int hosts_looked_up = 0;
2188 int hosts_retry = 0;
2189 int hosts_serial = 0;
2190 int hosts_total = 0;
2191 int total_hosts_tried = 0;
2193 BOOL expired = TRUE;
2194 BOOL continuing = continue_hostname != NULL;
2195 uschar *expanded_hosts = NULL;
2197 uschar *tid = string_sprintf("%s transport", tblock->name);
2198 smtp_transport_options_block *ob =
2199 (smtp_transport_options_block *)(tblock->options_block);
2200 host_item *hostlist = addrlist->host_list;
2201 host_item *host = NULL;
2205 debug_printf("%s transport entered\n", tblock->name);
2206 for (addr = addrlist; addr != NULL; addr = addr->next)
2207 debug_printf(" %s\n", addr->address);
2208 if (continuing) debug_printf("already connected to %s [%s]\n",
2209 continue_hostname, continue_host_address);
2212 /* Set the flag requesting that these hosts be added to the waiting
2213 database if the delivery fails temporarily or if we are running with
2214 queue_smtp or a 2-stage queue run. This gets unset for certain
2215 kinds of error, typically those that are specific to the message. */
2217 update_waiting = TRUE;
2219 /* If a host list is not defined for the addresses - they must all have the
2220 same one in order to be passed to a single transport - or if the transport has
2221 a host list with hosts_override set, use the host list supplied with the
2222 transport. It is an error for this not to exist. */
2224 if (hostlist == NULL || (ob->hosts_override && ob->hosts != NULL))
2226 if (ob->hosts == NULL)
2228 addrlist->message = string_sprintf("%s transport called with no hosts set",
2230 addrlist->transport_return = PANIC;
2231 return FALSE; /* Only top address has status */
2234 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
2237 /* If the transport's host list contains no '$' characters, and we are not
2238 randomizing, it is fixed and therefore a chain of hosts can be built once
2239 and for all, and remembered for subsequent use by other calls to this
2240 transport. If, on the other hand, the host list does contain '$', or we are
2241 randomizing its order, we have to rebuild it each time. In the fixed case,
2242 as the hosts string will never be used again, it doesn't matter that we
2243 replace all the : characters with zeros. */
2245 if (ob->hostlist == NULL)
2247 uschar *s = ob->hosts;
2249 if (Ustrchr(s, '$') != NULL)
2251 expanded_hosts = expand_string(s);
2252 if (expanded_hosts == NULL)
2254 addrlist->message = string_sprintf("failed to expand list of hosts "
2255 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
2256 addrlist->transport_return = search_find_defer? DEFER : PANIC;
2257 return FALSE; /* Only top address has status */
2259 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
2260 "\"%s\"\n", s, expanded_hosts);
2264 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
2266 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
2268 /* Check that the expansion yielded something useful. */
2269 if (hostlist == NULL)
2272 string_sprintf("%s transport has empty hosts setting", tblock->name);
2273 addrlist->transport_return = PANIC;
2274 return FALSE; /* Only top address has status */
2277 /* If there was no expansion of hosts, save the host list for
2280 if (expanded_hosts == NULL) ob->hostlist = hostlist;
2283 /* This is not the first time this transport has been run in this delivery;
2284 the host list was built previously. */
2286 else hostlist = ob->hostlist;
2289 /* The host list was supplied with the address. If hosts_randomize is set, we
2290 must sort it into a random order if it did not come from MX records and has not
2291 already been randomized (but don't bother if continuing down an existing
2294 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continuing)
2296 host_item *newlist = NULL;
2297 while (hostlist != NULL)
2299 host_item *h = hostlist;
2300 hostlist = hostlist->next;
2302 h->sort_key = random_number(100);
2304 if (newlist == NULL)
2309 else if (h->sort_key < newlist->sort_key)
2316 host_item *hh = newlist;
2317 while (hh->next != NULL)
2319 if (h->sort_key < hh->next->sort_key) break;
2327 hostlist = addrlist->host_list = newlist;
2331 /* Sort out the default port. */
2333 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
2336 /* For each host-plus-IP-address on the list:
2338 . If this is a continued delivery and the host isn't the one with the
2339 current connection, skip.
2341 . If the status is unusable (i.e. previously failed or retry checked), skip.
2343 . If no IP address set, get the address, either by turning the name into
2344 an address, calling gethostbyname if gethostbyname is on, or by calling
2345 the DNS. The DNS may yield multiple addresses, in which case insert the
2346 extra ones into the list.
2348 . Get the retry data if not previously obtained for this address and set the
2349 field which remembers the state of this address. Skip if the retry time is
2350 not reached. If not, remember whether retry data was found. The retry string
2351 contains both the name and the IP address.
2353 . Scan the list of addresses and mark those whose status is DEFER as
2354 PENDING_DEFER. These are the only ones that will be processed in this cycle
2357 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
2358 Some addresses may be successfully delivered, others may fail, and yet
2359 others may get temporary errors and so get marked DEFER.
2361 . The return from the delivery attempt is OK if a connection was made and a
2362 valid SMTP dialogue was completed. Otherwise it is DEFER.
2364 . If OK, add a "remove" retry item for this host/IPaddress, if any.
2366 . If fail to connect, or other defer state, add a retry item.
2368 . If there are any addresses whose status is still DEFER, carry on to the
2369 next host/IPaddress, unless we have tried the number of hosts given
2370 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
2371 there is some fancy logic for hosts_max_try that means its limit can be
2372 overstepped in some circumstances.
2374 If we get to the end of the list, all hosts have deferred at least one address,
2375 or not reached their retry times. If delay_after_cutoff is unset, it requests a
2376 delivery attempt to those hosts whose last try was before the arrival time of
2377 the current message. To cope with this, we have to go round the loop a second
2378 time. After that, set the status and error data for any addresses that haven't
2379 had it set already. */
2381 for (cutoff_retry = 0; expired &&
2382 cutoff_retry < ((ob->delay_after_cutoff)? 1 : 2);
2385 host_item *nexthost = NULL;
2386 int unexpired_hosts_tried = 0;
2388 for (host = hostlist;
2390 unexpired_hosts_tried < ob->hosts_max_try &&
2391 total_hosts_tried < ob->hosts_max_try_hardlimit;
2397 BOOL serialized = FALSE;
2398 BOOL host_is_expired = FALSE;
2399 BOOL message_defer = FALSE;
2400 BOOL ifchanges = FALSE;
2401 BOOL some_deferred = FALSE;
2402 address_item *first_addr = NULL;
2403 uschar *interface = NULL;
2404 uschar *retry_host_key = NULL;
2405 uschar *retry_message_key = NULL;
2406 uschar *serialize_key = NULL;
2408 /* Default next host is next host. :-) But this can vary if the
2409 hosts_max_try limit is hit (see below). It may also be reset if a host
2410 address is looked up here (in case the host was multihomed). */
2412 nexthost = host->next;
2414 /* If the address hasn't yet been obtained from the host name, look it up
2415 now, unless the host is already marked as unusable. If it is marked as
2416 unusable, it means that the router was unable to find its IP address (in
2417 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
2418 the lookup failed last time. We don't get this far if *all* MX records
2419 point to non-existent hosts; that is treated as a hard error.
2421 We can just skip this host entirely. When the hosts came from the router,
2422 the address will timeout based on the other host(s); when the address is
2423 looked up below, there is an explicit retry record added.
2425 Note that we mustn't skip unusable hosts if the address is not unset; they
2426 may be needed as expired hosts on the 2nd time round the cutoff loop. */
2428 if (host->address == NULL)
2430 int new_port, flags;
2432 uschar *canonical_name;
2434 if (host->status >= hstatus_unusable)
2436 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
2441 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
2443 /* The host name is permitted to have an attached port. Find it, and
2444 strip it from the name. Just remember it for now. */
2446 new_port = host_item_get_port(host);
2448 /* Count hosts looked up */
2452 /* Find by name if so configured, or if it's an IP address. We don't
2453 just copy the IP address, because we need the test-for-local to happen. */
2455 flags = HOST_FIND_BY_A;
2456 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
2457 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
2459 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
2460 rc = host_find_byname(host, NULL, flags, &canonical_name, TRUE);
2462 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
2463 &canonical_name, NULL);
2465 /* Update the host (and any additional blocks, resulting from
2466 multihoming) with a host-specific port, if any. */
2468 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
2470 /* Failure to find the host at this time (usually DNS temporary failure)
2471 is really a kind of routing failure rather than a transport failure.
2472 Therefore we add a retry item of the routing kind, not to stop us trying
2473 to look this name up here again, but to ensure the address gets timed
2474 out if the failures go on long enough. A complete failure at this point
2475 commonly points to a configuration error, but the best action is still
2476 to carry on for the next host. */
2478 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
2480 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
2482 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
2483 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
2484 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
2485 host->status = hstatus_unusable;
2487 for (addr = addrlist; addr != NULL; addr = addr->next)
2489 if (addr->transport_return != DEFER) continue;
2490 addr->basic_errno = ERRNO_UNKNOWNHOST;
2492 string_sprintf("failed to lookup IP address for %s", host->name);
2497 /* If the host is actually the local host, we may have a problem, or
2498 there may be some cunning configuration going on. In the problem case,
2499 log things and give up. The default transport status is already DEFER. */
2501 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
2503 for (addr = addrlist; addr != NULL; addr = addr->next)
2505 addr->basic_errno = 0;
2506 addr->message = string_sprintf("%s transport found host %s to be "
2507 "local", tblock->name, host->name);
2511 } /* End of block for IP address lookup */
2513 /* If this is a continued delivery, we are interested only in the host
2514 which matches the name of the existing open channel. The check is put
2515 here after the local host lookup, in case the name gets expanded as a
2516 result of the lookup. Set expired FALSE, to save the outer loop executing
2519 if (continuing && (Ustrcmp(continue_hostname, host->name) != 0 ||
2520 Ustrcmp(continue_host_address, host->address) != 0))
2523 continue; /* With next host */
2526 /* Reset the default next host in case a multihomed host whose addresses
2527 are not looked up till just above added to the host list. */
2529 nexthost = host->next;
2531 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
2532 domain is in queue_smtp_domains, we don't actually want to attempt any
2533 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
2534 there is a lookup defer in queue_smtp_domains, proceed as if the domain
2535 were not in it. We don't want to hold up all SMTP deliveries! Except when
2536 doing a two-stage queue run, don't do this if forcing. */
2538 if ((!deliver_force || queue_2stage) && (queue_smtp ||
2539 match_isinlist(addrlist->domain, &queue_smtp_domains, 0,
2540 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
2543 for (addr = addrlist; addr != NULL; addr = addr->next)
2545 if (addr->transport_return != DEFER) continue;
2546 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
2548 continue; /* With next host */
2551 /* Count hosts being considered - purely for an intelligent comment
2552 if none are usable. */
2556 /* Set $host and $host address now in case they are needed for the
2557 interface expansion or the serialize_hosts check; they remain set if an
2558 actual delivery happens. */
2560 deliver_host = host->name;
2561 deliver_host_address = host->address;
2563 /* Set up a string for adding to the retry key if the port number is not
2564 the standard SMTP port. A host may have its own port setting that overrides
2567 pistring = string_sprintf(":%d", (host->port == PORT_NONE)?
2569 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
2571 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
2572 string changes upon expansion, we must add it to the key that is used for
2573 retries, because connections to the same host from a different interface
2574 should be treated separately. */
2576 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET : AF_INET6;
2577 if (!smtp_get_interface(ob->interface, host_af, addrlist, &ifchanges,
2580 if (ifchanges) pistring = string_sprintf("%s/%s", pistring, interface);
2582 /* The first time round the outer loop, check the status of the host by
2583 inspecting the retry data. The second time round, we are interested only
2584 in expired hosts that haven't been tried since this message arrived. */
2586 if (cutoff_retry == 0)
2588 /* Ensure the status of the address is set by checking retry data if
2589 necessary. There maybe host-specific retry data (applicable to all
2590 messages) and also data for retries of a specific message at this host.
2591 If either of these retry records are actually read, the keys used are
2592 returned to save recomputing them later. */
2594 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
2595 ob->retry_include_ip_address, &retry_host_key, &retry_message_key);
2597 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
2598 (host->address == NULL)? US"" : host->address, pistring,
2599 (host->status == hstatus_usable)? "usable" :
2600 (host->status == hstatus_unusable)? "unusable" :
2601 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
2603 /* Skip this address if not usable at this time, noting if it wasn't
2604 actually expired, both locally and in the address. */
2606 switch (host->status)
2608 case hstatus_unusable:
2610 setflag(addrlist, af_retry_skipped);
2613 case hstatus_unusable_expired:
2616 case hwhy_retry: hosts_retry++; break;
2617 case hwhy_failed: hosts_fail++; break;
2618 case hwhy_deferred: hosts_defer++; break;
2621 /* If there was a retry message key, implying that previously there
2622 was a message-specific defer, we don't want to update the list of
2623 messages waiting for these hosts. */
2625 if (retry_message_key != NULL) update_waiting = FALSE;
2626 continue; /* With the next host or IP address */
2630 /* Second time round the loop: if the address is set but expired, and
2631 the message is newer than the last try, let it through. */
2635 if (host->address == NULL ||
2636 host->status != hstatus_unusable_expired ||
2637 host->last_try > received_time)
2640 debug_printf("trying expired host %s [%s]%s\n",
2641 host->name, host->address, pistring);
2642 host_is_expired = TRUE;
2645 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
2646 it remains TRUE only if all hosts are expired and none are actually tried.
2651 /* If this host is listed as one to which access must be serialized,
2652 see if another Exim process has a connection to it, and if so, skip
2653 this host. If not, update the database to record our connection to it
2654 and remember this for later deletion. Do not do any of this if we are
2655 sending the message down a pre-existing connection. */
2658 verify_check_this_host(&(ob->serialize_hosts), NULL, host->name,
2659 host->address, NULL) == OK)
2661 serialize_key = string_sprintf("host-serialize-%s", host->name);
2662 if (!enq_start(serialize_key))
2665 debug_printf("skipping host %s because another Exim process "
2666 "is connected to it\n", host->name);
2673 /* OK, we have an IP address that is not waiting for its retry time to
2674 arrive (it might be expired) OR (second time round the loop) we have an
2675 expired host that hasn't been tried since the message arrived. Have a go
2676 at delivering the message to it. First prepare the addresses by flushing
2677 out the result of previous attempts, and finding the first address that
2678 is still to be delivered. */
2680 first_addr = prepare_addresses(addrlist, host);
2682 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
2683 message_id, host->name, host->address, addrlist->address,
2684 (addrlist->next == NULL)? "" : ", ...");
2686 set_process_info("delivering %s to %s [%s] (%s%s)",
2687 message_id, host->name, host->address, addrlist->address,
2688 (addrlist->next == NULL)? "" : ", ...");
2690 /* This is not for real; don't do the delivery. If there are
2691 any remaining hosts, list them. */
2696 set_errno(addrlist, 0, NULL, OK, FALSE);
2697 for (addr = addrlist; addr != NULL; addr = addr->next)
2699 addr->host_used = host;
2700 addr->special_action = '*';
2701 addr->message = US"delivery bypassed by -N option";
2705 debug_printf("*** delivery by %s transport bypassed by -N option\n"
2706 "*** host and remaining hosts:\n", tblock->name);
2707 for (host2 = host; host2 != NULL; host2 = host2->next)
2708 debug_printf(" %s [%s]\n", host2->name,
2709 (host2->address == NULL)? US"unset" : host2->address);
2714 /* This is for real. If the host is expired, we don't count it for
2715 hosts_max_retry. This ensures that all hosts must expire before an address
2716 is timed out, unless hosts_max_try_hardlimit (which protects against
2717 lunatic DNS configurations) is reached.
2719 If the host is not expired and we are about to hit the hosts_max_retry
2720 limit, check to see if there is a subsequent hosts with a different MX
2721 value. If so, make that the next host, and don't count this one. This is a
2722 heuristic to make sure that different MXs do get tried. With a normal kind
2723 of retry rule, they would get tried anyway when the earlier hosts were
2724 delayed, but if the domain has a "retry every time" type of rule - as is
2725 often used for the the very large ISPs, that won't happen. */
2729 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
2733 debug_printf("hosts_max_try limit reached with this host\n");
2734 for (h = host; h != NULL; h = h->next)
2735 if (h->mx != host->mx) break;
2739 unexpired_hosts_tried--;
2740 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
2741 "and will be tried\n");
2745 /* Attempt the delivery. */
2747 total_hosts_tried++;
2748 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
2749 expanded_hosts != NULL, &message_defer, FALSE);
2752 OK => connection made, each address contains its result;
2753 message_defer is set for message-specific defers (when all
2754 recipients are marked defer)
2755 DEFER => there was a non-message-specific delivery problem;
2756 ERROR => there was a problem setting up the arguments for a filter,
2757 or there was a problem with expanding added headers
2760 /* If the result is not OK, there was a non-message-specific problem.
2761 If the result is DEFER, we need to write to the logs saying what happened
2762 for this particular host, except in the case of authentication and TLS
2763 failures, where the log has already been written. If all hosts defer a
2764 general message is written at the end. */
2766 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL &&
2767 first_addr->basic_errno != ERRNO_TLSFAILURE)
2768 write_logs(first_addr, host);
2770 /* If STARTTLS was accepted, but there was a failure in setting up the
2771 TLS session (usually a certificate screwup), and the host is not in
2772 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
2773 TLS forcibly turned off. We have to start from scratch with a new SMTP
2774 connection. That's why the retry is done from here, not from within
2775 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
2776 session, so the in-clear transmission after those errors, if permitted,
2777 happens inside smtp_deliver().] */
2780 if (rc == DEFER && first_addr->basic_errno == ERRNO_TLSFAILURE &&
2781 ob->tls_tempfail_tryclear &&
2782 verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
2783 host->address, NULL) != OK)
2785 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
2786 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
2787 first_addr = prepare_addresses(addrlist, host);
2788 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
2789 expanded_hosts != NULL, &message_defer, TRUE);
2790 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
2791 write_logs(first_addr, host);
2796 /* Delivery attempt finished */
2798 rs = (rc == OK)? US"OK" : (rc == DEFER)? US"DEFER" : (rc == ERROR)?
2801 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
2802 message_id, host->name, host->address, addrlist->address,
2803 (addrlist->next == NULL)? "" : " (& others)", rs);
2805 /* Release serialization if set up */
2807 if (serialized) enq_end(serialize_key);
2809 /* If the result is DEFER, or if a host retry record is known to exist, we
2810 need to add an item to the retry chain for updating the retry database
2811 at the end of delivery. We only need to add the item to the top address,
2812 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
2813 for any other delivery attempts using the same address. (It is copied into
2814 the unusable tree at the outer level, so even if different address blocks
2815 contain the same address, it still won't get tried again.) */
2817 if (rc == DEFER || retry_host_key != NULL)
2819 int delete_flag = (rc != DEFER)? rf_delete : 0;
2820 if (retry_host_key == NULL)
2822 retry_host_key = ob->retry_include_ip_address?
2823 string_sprintf("T:%S:%s%s", host->name, host->address, pistring) :
2824 string_sprintf("T:%S%s", host->name, pistring);
2827 /* If a delivery of another message over an existing SMTP connection
2828 yields DEFER, we do NOT set up retry data for the host. This covers the
2829 case when there are delays in routing the addresses in the second message
2830 that are so long that the server times out. This is alleviated by not
2831 routing addresses that previously had routing defers when handling an
2832 existing connection, but even so, this case may occur (e.g. if a
2833 previously happily routed address starts giving routing defers). If the
2834 host is genuinely down, another non-continued message delivery will
2835 notice it soon enough. */
2837 if (delete_flag != 0 || !continuing)
2838 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
2840 /* We may have tried an expired host, if its retry time has come; ensure
2841 the status reflects the expiry for the benefit of any other addresses. */
2845 host->status = (host_is_expired)?
2846 hstatus_unusable_expired : hstatus_unusable;
2847 host->why = hwhy_deferred;
2851 /* If message_defer is set (host was OK, but every recipient got deferred
2852 because of some message-specific problem), or if that had happened
2853 previously so that a message retry key exists, add an appropriate item
2854 to the retry chain. Note that if there was a message defer but now there is
2855 a host defer, the message defer record gets deleted. That seems perfectly
2856 reasonable. Also, stop the message from being remembered as waiting
2857 for specific hosts. */
2859 if (message_defer || retry_message_key != NULL)
2861 int delete_flag = message_defer? 0 : rf_delete;
2862 if (retry_message_key == NULL)
2864 retry_message_key = ob->retry_include_ip_address?
2865 string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
2867 string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
2869 retry_add_item(addrlist, retry_message_key,
2870 rf_message | rf_host | delete_flag);
2871 update_waiting = FALSE;
2874 /* Any return other than DEFER (that is, OK or ERROR) means that the
2875 addresses have got their final statuses filled in for this host. In the OK
2876 case, see if any of them are deferred. */
2880 for (addr = addrlist; addr != NULL; addr = addr->next)
2882 if (addr->transport_return == DEFER)
2884 some_deferred = TRUE;
2890 /* If no addresses deferred or the result was ERROR, return. We do this for
2891 ERROR because a failing filter set-up or add_headers expansion is likely to
2892 fail for any host we try. */
2894 if (rc == ERROR || (rc == OK && !some_deferred))
2896 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
2897 return TRUE; /* Each address has its status */
2900 /* If the result was DEFER or some individual addresses deferred, let
2901 the loop run to try other hosts with the deferred addresses, except for the
2902 case when we were trying to deliver down an existing channel and failed.
2903 Don't try any other hosts in this case. */
2905 if (continuing) break;
2907 /* If the whole delivery, or some individual addresses, were deferred and
2908 there are more hosts that could be tried, do not count this host towards
2909 the hosts_max_try limit if the age of the message is greater than the
2910 maximum retry time for this host. This means we may try try all hosts,
2911 ignoring the limit, when messages have been around for some time. This is
2912 important because if we don't try all hosts, the address will never time
2913 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
2915 if ((rc == DEFER || some_deferred) && nexthost != NULL)
2918 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
2920 if (retry != NULL && retry->rules != NULL)
2922 retry_rule *last_rule;
2923 for (last_rule = retry->rules;
2924 last_rule->next != NULL;
2925 last_rule = last_rule->next);
2926 timedout = time(NULL) - received_time > last_rule->timeout;
2928 else timedout = TRUE; /* No rule => timed out */
2932 unexpired_hosts_tried--;
2933 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
2934 "hosts_max_try (message older than host's retry time)\n");
2937 } /* End of loop for trying multiple hosts. */
2939 /* This is the end of the loop that repeats iff expired is TRUE and
2940 ob->delay_after_cutoff is FALSE. The second time round we will
2941 try those hosts that haven't been tried since the message arrived. */
2945 debug_printf("all IP addresses skipped or deferred at least one address\n");
2946 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
2947 debug_printf("retrying IP addresses not tried since message arrived\n");
2952 /* Get here if all IP addresses are skipped or defer at least one address. In
2953 MUA wrapper mode, this will happen only for connection or other non-message-
2954 specific failures. Force the delivery status for all addresses to FAIL. */
2958 for (addr = addrlist; addr != NULL; addr = addr->next)
2959 addr->transport_return = FAIL;
2963 /* In the normal, non-wrapper case, add a standard message to each deferred
2964 address if there hasn't been an error, that is, if it hasn't actually been
2965 tried this time. The variable "expired" will be FALSE if any deliveries were
2966 actually tried, or if there was at least one host that was not expired. That
2967 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
2968 a delivery has been tried, an error code will be set, and the failing of the
2969 message is handled by the retry code later.
2971 If queue_smtp is set, or this transport was called to send a subsequent message
2972 down an existing TCP/IP connection, and something caused the host not to be
2973 found, we end up here, but can detect these cases and handle them specially. */
2975 for (addr = addrlist; addr != NULL; addr = addr->next)
2977 /* If host is not NULL, it means that we stopped processing the host list
2978 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
2979 means we need to behave as if some hosts were skipped because their retry
2980 time had not come. Specifically, this prevents the address from timing out.
2981 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
2982 hosts were tried. */
2986 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
2989 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
2990 "hosts were tried\n");
2995 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
2996 setflag(addr, af_retry_skipped);
3000 if (queue_smtp) /* no deliveries attempted */
3002 addr->transport_return = DEFER;
3003 addr->basic_errno = 0;
3004 addr->message = US"SMTP delivery explicitly queued";
3007 else if (addr->transport_return == DEFER &&
3008 (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0) &&
3009 addr->message == NULL)
3011 addr->basic_errno = ERRNO_HRETRY;
3012 if (continue_hostname != NULL)
3014 addr->message = US"no host found for existing SMTP connection";
3018 setflag(addr, af_pass_message); /* This is not a security risk */
3019 addr->message = (ob->delay_after_cutoff)?
3020 US"retry time not reached for any host after a long failure period" :
3021 US"all hosts have been failing for a long time and were last tried "
3022 "after this message arrived";
3024 /* If we are already using fallback hosts, or there are no fallback hosts
3025 defined, convert the result to FAIL to cause a bounce. */
3027 if (addr->host_list == addr->fallback_hosts ||
3028 addr->fallback_hosts == NULL)
3029 addr->transport_return = FAIL;
3033 if (hosts_retry == hosts_total)
3034 addr->message = US"retry time not reached for any host";
3035 else if (hosts_fail == hosts_total)
3036 addr->message = US"all host address lookups failed permanently";
3037 else if (hosts_defer == hosts_total)
3038 addr->message = US"all host address lookups failed temporarily";
3039 else if (hosts_serial == hosts_total)
3040 addr->message = US"connection limit reached for all hosts";
3041 else if (hosts_fail+hosts_defer == hosts_total)
3042 addr->message = US"all host address lookups failed";
3043 else addr->message = US"some host address lookups failed and retry time "
3044 "not reached for other hosts or connection limit reached";
3049 /* Update the database which keeps information about which messages are waiting
3050 for which hosts to become available. For some message-specific errors, the
3051 update_waiting flag is turned off because we don't want follow-on deliveries in
3054 if (update_waiting) transport_update_waiting(hostlist, tblock->name);
3058 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3060 return TRUE; /* Each address has its status */
3063 /* End of transport/smtp.c */