1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2012 */
6 /* See the file NOTICE for conditions of use and distribution. */
12 #define PENDING_DEFER (PENDING + DEFER)
13 #define PENDING_OK (PENDING + OK)
16 /* Options specific to the smtp transport. This transport also supports LMTP
17 over TCP/IP. The options must be in alphabetic order (note that "_" comes
18 before the lower case letters). Some live in the transport_instance block so as
19 to be publicly visible; these are flagged with opt_public. */
21 optionlist smtp_transport_options[] = {
22 { "address_retry_include_sender", opt_bool,
23 (void *)offsetof(smtp_transport_options_block, address_retry_include_sender) },
24 { "allow_localhost", opt_bool,
25 (void *)offsetof(smtp_transport_options_block, allow_localhost) },
26 { "authenticated_sender", opt_stringptr,
27 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
28 { "authenticated_sender_force", opt_bool,
29 (void *)offsetof(smtp_transport_options_block, authenticated_sender_force) },
30 { "command_timeout", opt_time,
31 (void *)offsetof(smtp_transport_options_block, command_timeout) },
32 { "connect_timeout", opt_time,
33 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
34 { "connection_max_messages", opt_int | opt_public,
35 (void *)offsetof(transport_instance, connection_max_messages) },
36 { "data_timeout", opt_time,
37 (void *)offsetof(smtp_transport_options_block, data_timeout) },
38 { "delay_after_cutoff", opt_bool,
39 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
41 { "dkim_canon", opt_stringptr,
42 (void *)offsetof(smtp_transport_options_block, dkim_canon) },
43 { "dkim_domain", opt_stringptr,
44 (void *)offsetof(smtp_transport_options_block, dkim_domain) },
45 { "dkim_private_key", opt_stringptr,
46 (void *)offsetof(smtp_transport_options_block, dkim_private_key) },
47 { "dkim_selector", opt_stringptr,
48 (void *)offsetof(smtp_transport_options_block, dkim_selector) },
49 { "dkim_sign_headers", opt_stringptr,
50 (void *)offsetof(smtp_transport_options_block, dkim_sign_headers) },
51 { "dkim_strict", opt_stringptr,
52 (void *)offsetof(smtp_transport_options_block, dkim_strict) },
54 { "dns_qualify_single", opt_bool,
55 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
56 { "dns_search_parents", opt_bool,
57 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
58 { "dscp", opt_stringptr,
59 (void *)offsetof(smtp_transport_options_block, dscp) },
60 { "fallback_hosts", opt_stringptr,
61 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
62 { "final_timeout", opt_time,
63 (void *)offsetof(smtp_transport_options_block, final_timeout) },
64 { "gethostbyname", opt_bool,
65 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
67 /* These are no longer honoured, as of Exim 4.80; for now, we silently
68 ignore; a later release will warn, and a later-still release will remove
69 these options, so that using them becomes an error. */
70 { "gnutls_require_kx", opt_stringptr,
71 (void *)offsetof(smtp_transport_options_block, gnutls_require_kx) },
72 { "gnutls_require_mac", opt_stringptr,
73 (void *)offsetof(smtp_transport_options_block, gnutls_require_mac) },
74 { "gnutls_require_protocols", opt_stringptr,
75 (void *)offsetof(smtp_transport_options_block, gnutls_require_proto) },
77 { "helo_data", opt_stringptr,
78 (void *)offsetof(smtp_transport_options_block, helo_data) },
79 { "hosts", opt_stringptr,
80 (void *)offsetof(smtp_transport_options_block, hosts) },
81 { "hosts_avoid_esmtp", opt_stringptr,
82 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
83 { "hosts_avoid_pipelining", opt_stringptr,
84 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
86 { "hosts_avoid_tls", opt_stringptr,
87 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
89 { "hosts_max_try", opt_int,
90 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
91 { "hosts_max_try_hardlimit", opt_int,
92 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
94 { "hosts_nopass_tls", opt_stringptr,
95 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
97 { "hosts_override", opt_bool,
98 (void *)offsetof(smtp_transport_options_block, hosts_override) },
99 { "hosts_randomize", opt_bool,
100 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
101 { "hosts_require_auth", opt_stringptr,
102 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
104 { "hosts_require_tls", opt_stringptr,
105 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
107 { "hosts_try_auth", opt_stringptr,
108 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
109 #ifdef EXPERIMENTAL_PRDR
110 { "hosts_try_prdr", opt_stringptr,
111 (void *)offsetof(smtp_transport_options_block, hosts_try_prdr) },
114 { "hosts_verify_avoid_tls", opt_stringptr,
115 (void *)offsetof(smtp_transport_options_block, hosts_verify_avoid_tls) },
117 { "interface", opt_stringptr,
118 (void *)offsetof(smtp_transport_options_block, interface) },
119 { "keepalive", opt_bool,
120 (void *)offsetof(smtp_transport_options_block, keepalive) },
121 { "lmtp_ignore_quota", opt_bool,
122 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
123 { "max_rcpt", opt_int | opt_public,
124 (void *)offsetof(transport_instance, max_addresses) },
125 { "multi_domain", opt_bool | opt_public,
126 (void *)offsetof(transport_instance, multi_domain) },
127 { "port", opt_stringptr,
128 (void *)offsetof(smtp_transport_options_block, port) },
129 { "protocol", opt_stringptr,
130 (void *)offsetof(smtp_transport_options_block, protocol) },
131 { "retry_include_ip_address", opt_bool,
132 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
133 { "serialize_hosts", opt_stringptr,
134 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
135 { "size_addition", opt_int,
136 (void *)offsetof(smtp_transport_options_block, size_addition) }
138 ,{ "tls_certificate", opt_stringptr,
139 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
140 { "tls_crl", opt_stringptr,
141 (void *)offsetof(smtp_transport_options_block, tls_crl) },
142 { "tls_dh_min_bits", opt_int,
143 (void *)offsetof(smtp_transport_options_block, tls_dh_min_bits) },
144 { "tls_privatekey", opt_stringptr,
145 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
146 { "tls_require_ciphers", opt_stringptr,
147 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
148 { "tls_sni", opt_stringptr,
149 (void *)offsetof(smtp_transport_options_block, tls_sni) },
150 { "tls_tempfail_tryclear", opt_bool,
151 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
152 { "tls_verify_certificates", opt_stringptr,
153 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) }
157 /* Size of the options list. An extern variable has to be used so that its
158 address can appear in the tables drtables.c. */
160 int smtp_transport_options_count =
161 sizeof(smtp_transport_options)/sizeof(optionlist);
163 /* Default private options block for the smtp transport. */
165 smtp_transport_options_block smtp_transport_option_defaults = {
167 NULL, /* fallback_hosts */
169 NULL, /* fallback_hostlist */
170 NULL, /* authenticated_sender */
171 US"$primary_hostname", /* helo_data */
172 NULL, /* interface */
174 US"smtp", /* protocol */
176 NULL, /* serialize_hosts */
177 NULL, /* hosts_try_auth */
178 NULL, /* hosts_require_auth */
179 #ifdef EXPERIMENTAL_PRDR
180 NULL, /* hosts_try_prdr */
182 NULL, /* hosts_require_tls */
183 NULL, /* hosts_avoid_tls */
184 US"*", /* hosts_verify_avoid_tls */
185 NULL, /* hosts_avoid_pipelining */
186 NULL, /* hosts_avoid_esmtp */
187 NULL, /* hosts_nopass_tls */
188 5*60, /* command_timeout */
189 5*60, /* connect_timeout; shorter system default overrides */
190 5*60, /* data timeout */
191 10*60, /* final timeout */
192 1024, /* size_addition */
193 5, /* hosts_max_try */
194 50, /* hosts_max_try_hardlimit */
195 TRUE, /* address_retry_include_sender */
196 FALSE, /* allow_localhost */
197 FALSE, /* authenticated_sender_force */
198 FALSE, /* gethostbyname */
199 TRUE, /* dns_qualify_single */
200 FALSE, /* dns_search_parents */
201 TRUE, /* delay_after_cutoff */
202 FALSE, /* hosts_override */
203 FALSE, /* hosts_randomize */
204 TRUE, /* keepalive */
205 FALSE, /* lmtp_ignore_quota */
206 TRUE /* retry_include_ip_address */
208 ,NULL, /* tls_certificate */
210 NULL, /* tls_privatekey */
211 NULL, /* tls_require_ciphers */
212 NULL, /* gnutls_require_kx */
213 NULL, /* gnutls_require_mac */
214 NULL, /* gnutls_require_proto */
216 NULL, /* tls_verify_certificates */
217 EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
218 /* tls_dh_min_bits */
219 TRUE /* tls_tempfail_tryclear */
222 ,NULL, /* dkim_canon */
223 NULL, /* dkim_domain */
224 NULL, /* dkim_private_key */
225 NULL, /* dkim_selector */
226 NULL, /* dkim_sign_headers */
227 NULL /* dkim_strict */
234 static uschar *smtp_command; /* Points to last cmd for error messages */
235 static uschar *mail_command; /* Points to MAIL cmd for error messages */
236 static BOOL update_waiting; /* TRUE to update the "wait" database */
239 /*************************************************
240 * Setup entry point *
241 *************************************************/
243 /* This function is called when the transport is about to be used,
244 but before running it in a sub-process. It is used for two things:
246 (1) To set the fallback host list in addresses, when delivering.
247 (2) To pass back the interface, port, protocol, and other options, for use
248 during callout verification.
251 tblock pointer to the transport instance block
252 addrlist list of addresses about to be transported
253 tf if not NULL, pointer to block in which to return options
254 uid the uid that will be set (not used)
255 gid the gid that will be set (not used)
256 errmsg place for error message (not used)
258 Returns: OK always (FAIL, DEFER not used)
262 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
263 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
265 smtp_transport_options_block *ob =
266 (smtp_transport_options_block *)(tblock->options_block);
268 errmsg = errmsg; /* Keep picky compilers happy */
272 /* Pass back options if required. This interface is getting very messy. */
276 tf->interface = ob->interface;
278 tf->protocol = ob->protocol;
279 tf->hosts = ob->hosts;
280 tf->hosts_override = ob->hosts_override;
281 tf->hosts_randomize = ob->hosts_randomize;
282 tf->gethostbyname = ob->gethostbyname;
283 tf->qualify_single = ob->dns_qualify_single;
284 tf->search_parents = ob->dns_search_parents;
285 tf->helo_data = ob->helo_data;
288 /* Set the fallback host list for all the addresses that don't have fallback
289 host lists, provided that the local host wasn't present in the original host
292 if (!testflag(addrlist, af_local_host_removed))
294 for (; addrlist != NULL; addrlist = addrlist->next)
295 if (addrlist->fallback_hosts == NULL)
296 addrlist->fallback_hosts = ob->fallback_hostlist;
304 /*************************************************
305 * Initialization entry point *
306 *************************************************/
308 /* Called for each instance, after its options have been read, to
309 enable consistency checks to be done, or anything else that needs
312 Argument: pointer to the transport instance block
317 smtp_transport_init(transport_instance *tblock)
319 smtp_transport_options_block *ob =
320 (smtp_transport_options_block *)(tblock->options_block);
322 /* Retry_use_local_part defaults FALSE if unset */
324 if (tblock->retry_use_local_part == TRUE_UNSET)
325 tblock->retry_use_local_part = FALSE;
327 /* Set the default port according to the protocol */
329 if (ob->port == NULL)
330 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
331 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
333 /* Set up the setup entry point, to be called before subprocesses for this
336 tblock->setup = smtp_transport_setup;
338 /* Complain if any of the timeouts are zero. */
340 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
341 ob->final_timeout <= 0)
342 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
343 "command, data, or final timeout value is zero for %s transport",
346 /* If hosts_override is set and there are local hosts, set the global
347 flag that stops verify from showing router hosts. */
349 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
351 /* If there are any fallback hosts listed, build a chain of host items
352 for them, but do not do any lookups at this time. */
354 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
361 /*************************************************
362 * Set delivery info into all active addresses *
363 *************************************************/
365 /* Only addresses whose status is >= PENDING are relevant. A lesser
366 status means that an address is not currently being processed.
369 addrlist points to a chain of addresses
370 errno_value to put in each address's errno field
371 msg to put in each address's message field
372 rc to put in each address's transport_return field
373 pass_message if TRUE, set the "pass message" flag in the address
375 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
376 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
377 this particular type of timeout.
383 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
388 if (errno_value == ERRNO_CONNECTTIMEOUT)
390 errno_value = ETIMEDOUT;
391 orvalue = RTEF_CTOUT;
393 for (addr = addrlist; addr != NULL; addr = addr->next)
395 if (addr->transport_return < PENDING) continue;
396 addr->basic_errno = errno_value;
397 addr->more_errno |= orvalue;
401 if (pass_message) setflag(addr, af_pass_message);
403 addr->transport_return = rc;
409 /*************************************************
410 * Check an SMTP response *
411 *************************************************/
413 /* This function is given an errno code and the SMTP response buffer
414 to analyse, together with the host identification for generating messages. It
415 sets an appropriate message and puts the first digit of the response code into
416 the yield variable. If no response was actually read, a suitable digit is
420 host the current host, to get its name for messages
421 errno_value pointer to the errno value
422 more_errno from the top address for use with ERRNO_FILTER_FAIL
423 buffer the SMTP response buffer
424 yield where to put a one-digit SMTP response code
425 message where to put an errror message
426 pass_message set TRUE if message is an SMTP response
428 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
431 static BOOL check_response(host_item *host, int *errno_value, int more_errno,
432 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
436 if (smtp_use_pipelining &&
437 (Ustrcmp(smtp_command, "MAIL") == 0 ||
438 Ustrcmp(smtp_command, "RCPT") == 0 ||
439 Ustrcmp(smtp_command, "DATA") == 0))
442 *yield = '4'; /* Default setting is to give a temporary error */
444 /* Handle response timeout */
446 if (*errno_value == ETIMEDOUT)
448 *message = US string_sprintf("SMTP timeout while connected to %s [%s] "
449 "after %s%s", host->name, host->address, pl, smtp_command);
450 if (transport_count > 0)
451 *message = US string_sprintf("%s (%d bytes written)", *message,
456 /* Handle malformed SMTP response */
458 if (*errno_value == ERRNO_SMTPFORMAT)
460 uschar *malfresp = string_printing(buffer);
461 while (isspace(*malfresp)) malfresp++;
463 *message = string_sprintf("Malformed SMTP reply (an empty line) from "
464 "%s [%s] in response to %s%s", host->name, host->address, pl,
467 *message = string_sprintf("Malformed SMTP reply from %s [%s] in response "
468 "to %s%s: %s", host->name, host->address, pl, smtp_command, malfresp);
472 /* Handle a failed filter process error; can't send QUIT as we mustn't
475 if (*errno_value == ERRNO_FILTER_FAIL)
477 *message = US string_sprintf("transport filter process failed (%d)%s",
479 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
483 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
486 if (*errno_value == ERRNO_CHHEADER_FAIL)
489 US string_sprintf("failed to expand headers_add or headers_remove: %s",
490 expand_string_message);
494 /* Handle failure to write a complete data block */
496 if (*errno_value == ERRNO_WRITEINCOMPLETE)
498 *message = US string_sprintf("failed to write a data block");
502 /* Handle error responses from the remote mailer. */
506 uschar *s = string_printing(buffer);
507 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
508 "host %s [%s]: %s", pl, smtp_command, host->name, host->address, s);
509 *pass_message = TRUE;
514 /* No data was read. If there is no errno, this must be the EOF (i.e.
515 connection closed) case, which causes deferral. An explicit connection reset
516 error has the same effect. Otherwise, put the host's identity in the message,
517 leaving the errno value to be interpreted as well. In all cases, we have to
518 assume the connection is now dead. */
520 if (*errno_value == 0 || *errno_value == ECONNRESET)
522 *errno_value = ERRNO_SMTPCLOSED;
523 *message = US string_sprintf("Remote host %s [%s] closed connection "
524 "in response to %s%s", host->name, host->address, pl, smtp_command);
526 else *message = US string_sprintf("%s [%s]", host->name, host->address);
533 /*************************************************
534 * Write error message to logs *
535 *************************************************/
537 /* This writes to the main log and to the message log.
540 addr the address item containing error information
541 host the current host
547 write_logs(address_item *addr, host_item *host)
549 if (addr->message != NULL)
551 uschar *message = addr->message;
552 if (addr->basic_errno > 0)
553 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
554 log_write(0, LOG_MAIN, "%s", message);
555 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
560 ((log_extra_selector & LX_outgoing_port) != 0)?
561 string_sprintf("%s [%s]:%d", host->name, host->address,
562 (host->port == PORT_NONE)? 25 : host->port)
564 string_sprintf("%s [%s]", host->name, host->address);
565 log_write(0, LOG_MAIN, "%s %s", msg, strerror(addr->basic_errno));
566 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), msg,
567 strerror(addr->basic_errno));
573 /*************************************************
574 * Synchronize SMTP responses *
575 *************************************************/
577 /* This function is called from smtp_deliver() to receive SMTP responses from
578 the server, and match them up with the commands to which they relate. When
579 PIPELINING is not in use, this function is called after every command, and is
580 therefore somewhat over-engineered, but it is simpler to use a single scheme
581 that works both with and without PIPELINING instead of having two separate sets
584 The set of commands that are buffered up with pipelining may start with MAIL
585 and may end with DATA; in between are RCPT commands that correspond to the
586 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
587 etc.) are never buffered.
589 Errors after MAIL or DATA abort the whole process leaving the response in the
590 buffer. After MAIL, pending responses are flushed, and the original command is
591 re-instated in big_buffer for error messages. For RCPT commands, the remote is
592 permitted to reject some recipient addresses while accepting others. However
593 certain errors clearly abort the whole process. Set the value in
594 transport_return to PENDING_OK if the address is accepted. If there is a
595 subsequent general error, it will get reset accordingly. If not, it will get
596 converted to OK at the end.
599 addrlist the complete address list
600 include_affixes TRUE if affixes include in RCPT
601 sync_addr ptr to the ptr of the one to start scanning at (updated)
602 host the host we are connected to
603 count the number of responses to read
605 include_sender true if 4xx retry is to include the sender it its key
606 pending_MAIL true if the first response is for MAIL
607 pending_DATA 0 if last command sent was not DATA
608 +1 if previously had a good recipient
609 -1 if not previously had a good recipient
610 inblock incoming SMTP block
611 timeout timeout value
612 buffer buffer for reading response
613 buffsize size of buffer
615 Returns: 3 if at least one address had 2xx and one had 5xx
616 2 if at least one address had 5xx but none had 2xx
617 1 if at least one host had a 2xx response, but none had 5xx
618 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
619 -1 timeout while reading RCPT response
620 -2 I/O or other non-response error for RCPT
621 -3 DATA or MAIL failed - errno and buffer set
625 sync_responses(address_item *addrlist, BOOL include_affixes,
626 address_item **sync_addr, host_item *host, int count,
627 BOOL address_retry_include_sender, BOOL pending_MAIL,
628 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
631 address_item *addr = *sync_addr;
634 /* Handle the response for a MAIL command. On error, reinstate the original
635 command in big_buffer for error message use, and flush any further pending
636 responses before returning, except after I/O errors and timeouts. */
641 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
643 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
644 if (errno == 0 && buffer[0] != 0)
646 uschar flushbuffer[4096];
648 if (buffer[0] == '4')
650 save_errno = ERRNO_MAIL4XX;
651 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
655 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
657 && (errno != 0 || flushbuffer[0] == 0))
666 if (pending_DATA) count--; /* Number of RCPT responses to come */
668 /* Read and handle the required number of RCPT responses, matching each one up
669 with an address by scanning for the next address whose status is PENDING_DEFER.
674 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
676 /* The address was accepted */
678 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
681 addr->transport_return = PENDING_OK;
683 /* If af_dr_retry_exists is set, there was a routing delay on this address;
684 ensure that any address-specific retry record is expunged. We do this both
685 for the basic key and for the version that also includes the sender. */
687 if (testflag(addr, af_dr_retry_exists))
689 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
691 retry_add_item(addr, altkey, rf_delete);
692 retry_add_item(addr, addr->address_retry_key, rf_delete);
696 /* Timeout while reading the response */
698 else if (errno == ETIMEDOUT)
700 int save_errno = errno;
701 uschar *message = string_sprintf("SMTP timeout while connected to %s [%s] "
702 "after RCPT TO:<%s>", host->name, host->address,
703 transport_rcpt_address(addr, include_affixes));
704 set_errno(addrlist, save_errno, message, DEFER, FALSE);
705 retry_add_item(addr, addr->address_retry_key, 0);
706 update_waiting = FALSE;
710 /* Handle other errors in obtaining an SMTP response by returning -1. This
711 will cause all the addresses to be deferred. Restore the SMTP command in
712 big_buffer for which we are checking the response, so the error message
715 else if (errno != 0 || buffer[0] == 0)
717 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
718 transport_rcpt_address(addr, include_affixes));
722 /* Handle SMTP permanent and temporary response codes. */
727 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
728 "host %s [%s]: %s", transport_rcpt_address(addr, include_affixes),
729 host->name, host->address, string_printing(buffer));
730 setflag(addr, af_pass_message);
731 deliver_msglog("%s %s\n", tod_stamp(tod_log), addr->message);
733 /* The response was 5xx */
735 if (buffer[0] == '5')
737 addr->transport_return = FAIL;
741 /* The response was 4xx */
745 addr->transport_return = DEFER;
746 addr->basic_errno = ERRNO_RCPT4XX;
747 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
749 /* Log temporary errors if there are more hosts to be tried. */
751 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", addr->message);
753 /* Do not put this message on the list of those waiting for specific
754 hosts, as otherwise it is likely to be tried too often. */
756 update_waiting = FALSE;
758 /* Add a retry item for the address so that it doesn't get tried again
759 too soon. If address_retry_include_sender is true, add the sender address
762 if (address_retry_include_sender)
764 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
766 retry_add_item(addr, altkey, 0);
768 else retry_add_item(addr, addr->address_retry_key, 0);
771 } /* Loop for next RCPT response */
773 /* Update where to start at for the next block of responses, unless we
774 have already handled all the addresses. */
776 if (addr != NULL) *sync_addr = addr->next;
778 /* Handle a response to DATA. If we have not had any good recipients, either
779 previously or in this block, the response is ignored. */
781 if (pending_DATA != 0 &&
782 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
787 if (pending_DATA > 0 || (yield & 1) != 0)
789 if (errno == 0 && buffer[0] == '4')
791 errno = ERRNO_DATA4XX;
792 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
796 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
797 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
798 "is in use and there were no good recipients\n", msg);
801 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
802 present) received 3xx. If any RCPTs were handled and yielded anything other
803 than 4xx, yield will be set non-zero. */
810 /*************************************************
811 * Deliver address list to given host *
812 *************************************************/
814 /* If continue_hostname is not null, we get here only when continuing to
815 deliver down an existing channel. The channel was passed as the standard
816 input. TLS is never active on a passed channel; the previous process always
817 closes it down before passing the connection on.
819 Otherwise, we have to make a connection to the remote host, and do the
820 initial protocol exchange.
822 When running as an MUA wrapper, if the sender or any recipient is rejected,
823 temporarily or permanently, we force failure for all recipients.
826 addrlist chain of potential addresses to deliver; only those whose
827 transport_return field is set to PENDING_DEFER are currently
828 being processed; others should be skipped - they have either
829 been delivered to an earlier host or IP address, or been
830 failed by one of them.
831 host host to deliver to
832 host_af AF_INET or AF_INET6
833 port default TCP/IP port to use, in host byte order
834 interface interface to bind to, or NULL
835 tblock transport instance block
836 copy_host TRUE if host set in addr->host_used must be copied, because
837 it is specific to this call of the transport
838 message_defer set TRUE if yield is OK, but all addresses were deferred
839 because of a non-recipient, non-host failure, that is, a
840 4xx response to MAIL FROM, DATA, or ".". This is a defer
841 that is specific to the message.
842 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
843 a second attempt after TLS initialization fails
845 Returns: OK - the connection was made and the delivery attempted;
846 the result for each address is in its data block.
847 DEFER - the connection could not be made, or something failed
848 while setting up the SMTP session, or there was a
849 non-message-specific error, such as a timeout.
850 ERROR - a filter command is specified for this transport,
851 and there was a problem setting it up; OR helo_data
852 or add_headers or authenticated_sender is specified
853 for this transport, and the string failed to expand
857 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
858 uschar *interface, transport_instance *tblock, BOOL copy_host,
859 BOOL *message_defer, BOOL suppress_tls)
862 address_item *sync_addr;
863 address_item *first_addr = addrlist;
868 time_t start_delivery_time = time(NULL);
869 smtp_transport_options_block *ob =
870 (smtp_transport_options_block *)(tblock->options_block);
871 BOOL lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
872 BOOL smtps = strcmpic(ob->protocol, US"smtps") == 0;
874 BOOL send_rset = TRUE;
875 BOOL send_quit = TRUE;
876 BOOL setting_up = TRUE;
877 BOOL completed_address = FALSE;
880 BOOL pass_message = FALSE;
881 #ifdef EXPERIMENTAL_PRDR
882 BOOL prdr_offered = FALSE;
885 smtp_inblock inblock;
886 smtp_outblock outblock;
887 int max_rcpt = tblock->max_addresses;
888 uschar *igquotstr = US"";
889 uschar *local_authenticated_sender = authenticated_sender;
890 uschar *helo_data = NULL;
891 uschar *message = NULL;
892 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
895 uschar inbuffer[4096];
896 uschar outbuffer[1024];
898 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
900 *message_defer = FALSE;
901 smtp_command = US"initial connection";
902 if (max_rcpt == 0) max_rcpt = 999999;
904 /* Set up the buffer for reading SMTP response packets. */
906 inblock.buffer = inbuffer;
907 inblock.buffersize = sizeof(inbuffer);
908 inblock.ptr = inbuffer;
909 inblock.ptrend = inbuffer;
911 /* Set up the buffer for holding SMTP commands while pipelining */
913 outblock.buffer = outbuffer;
914 outblock.buffersize = sizeof(outbuffer);
915 outblock.ptr = outbuffer;
916 outblock.cmd_count = 0;
917 outblock.authenticating = FALSE;
919 /* Reset the parameters of a TLS session. */
922 tls_in.cipher = NULL; /* for back-compatible behaviour */
923 tls_in.peerdn = NULL;
924 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
929 tls_out.cipher = NULL; /* the one we may use for this transport */
930 tls_out.peerdn = NULL;
931 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
938 set_errno(addrlist, 0, US"TLS support not available", DEFER, FALSE);
943 /* Make a connection to the host if this isn't a continued delivery, and handle
944 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
945 specially so they can be identified for retries. */
947 if (continue_hostname == NULL)
949 inblock.sock = outblock.sock =
950 smtp_connect(host, host_af, port, interface, ob->connect_timeout,
951 ob->keepalive, ob->dscp); /* This puts port into host->port */
953 if (inblock.sock < 0)
955 set_errno(addrlist, (errno == ETIMEDOUT)? ERRNO_CONNECTTIMEOUT : errno,
960 /* Expand the greeting message while waiting for the initial response. (Makes
961 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
962 delayed till here so that $sending_interface and $sending_port are set. */
964 helo_data = expand_string(ob->helo_data);
966 /* The first thing is to wait for an initial OK response. The dreaded "goto"
967 is nevertheless a reasonably clean way of programming this kind of logic,
968 where you want to escape on any error. */
972 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
973 ob->command_timeout)) goto RESPONSE_FAILED;
975 /* Now check if the helo_data expansion went well, and sign off cleanly if
978 if (helo_data == NULL)
980 uschar *message = string_sprintf("failed to expand helo_data: %s",
981 expand_string_message);
982 set_errno(addrlist, 0, message, DEFER, FALSE);
988 /** Debugging without sending a message
989 addrlist->transport_return = DEFER;
993 /* Errors that occur after this point follow an SMTP command, which is
994 left in big_buffer by smtp_write_command() for use in error messages. */
996 smtp_command = big_buffer;
998 /* Tell the remote who we are...
1000 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1001 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1002 greeting is of this form. The assumption was that the far end supports it
1003 properly... but experience shows that there are some that give 5xx responses,
1004 even though the banner includes "ESMTP" (there's a bloody-minded one that
1005 says "ESMTP not spoken here"). Cope with that case.
1007 September 2000: Time has passed, and it seems reasonable now to always send
1008 EHLO at the start. It is also convenient to make the change while installing
1011 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1012 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1013 would be no way to send out the mails, so there is now a host list
1014 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1015 PIPELINING problem as well. Maybe it can also be useful to cure other
1016 problems with broken servers.
1018 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1019 Then somebody tried it with a Microsoft mailer... It seems that all other
1020 mailers use upper case for some reason (the RFC is quite clear about case
1021 independence) so, for peace of mind, I gave in. */
1023 esmtp = verify_check_this_host(&(ob->hosts_avoid_esmtp), NULL,
1024 host->name, host->address, NULL) != OK;
1026 /* Alas; be careful, since this goto is not an error-out, so conceivably
1027 we might set data between here and the target which we assume to exist
1028 and be usable. I can see this coming back to bite us. */
1033 suppress_tls = FALSE;
1034 ob->tls_tempfail_tryclear = FALSE;
1035 smtp_command = US"SSL-on-connect";
1042 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1043 lmtp? "LHLO" : "EHLO", helo_data) < 0)
1045 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1046 ob->command_timeout))
1048 if (errno != 0 || buffer[0] == 0 || lmtp) goto RESPONSE_FAILED;
1055 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1060 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1062 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1063 ob->command_timeout)) goto RESPONSE_FAILED;
1066 /* Set IGNOREQUOTA if the response to LHLO specifies support and the
1067 lmtp_ignore_quota option was set. */
1069 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1070 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1071 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1073 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1076 tls_offered = esmtp &&
1077 pcre_exec(regex_STARTTLS, NULL, CS buffer, Ustrlen(buffer), 0,
1078 PCRE_EOPT, NULL, 0) >= 0;
1081 #ifdef EXPERIMENTAL_PRDR
1082 prdr_offered = esmtp &&
1083 (pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(buffer), 0,
1084 PCRE_EOPT, NULL, 0) >= 0) &&
1085 (verify_check_this_host(&(ob->hosts_try_prdr), NULL, host->name,
1086 host->address, NULL) == OK);
1089 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1093 /* For continuing deliveries down the same channel, the socket is the standard
1094 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1095 below). Set up the pointer to where subsequent commands will be left, for
1096 error messages. Note that smtp_use_size and smtp_use_pipelining will have been
1097 set from the command line if they were set in the process that passed the
1102 inblock.sock = outblock.sock = fileno(stdin);
1103 smtp_command = big_buffer;
1104 host->port = port; /* Record the port that was used */
1107 /* If TLS is available on this connection, whether continued or not, attempt to
1108 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1109 send another EHLO - the server may give a different answer in secure mode. We
1110 use a separate buffer for reading the response to STARTTLS so that if it is
1111 negative, the original EHLO data is available for subsequent analysis, should
1112 the client not be required to use TLS. If the response is bad, copy the buffer
1113 for error analysis. */
1116 if (tls_offered && !suppress_tls &&
1117 verify_check_this_host(&(ob->hosts_avoid_tls), NULL, host->name,
1118 host->address, NULL) != OK)
1120 uschar buffer2[4096];
1121 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1124 /* If there is an I/O error, transmission of this message is deferred. If
1125 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1126 false, we also defer. However, if there is a temporary rejection of STARTTLS
1127 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1128 STARTTLS, we carry on. This means we will try to send the message in clear,
1129 unless the host is in hosts_require_tls (tested below). */
1131 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1132 ob->command_timeout))
1134 if (errno != 0 || buffer2[0] == 0 ||
1135 (buffer2[0] == '4' && !ob->tls_tempfail_tryclear))
1137 Ustrncpy(buffer, buffer2, sizeof(buffer));
1138 goto RESPONSE_FAILED;
1142 /* STARTTLS accepted: try to negotiate a TLS session. */
1147 int rc = tls_client_start(inblock.sock,
1150 NULL, /* No DH param */
1151 ob->tls_certificate,
1154 ob->tls_verify_certificates,
1156 ob->tls_require_ciphers,
1157 ob->tls_dh_min_bits,
1158 ob->command_timeout);
1160 /* TLS negotiation failed; give an error. From outside, this function may
1161 be called again to try in clear on a new connection, if the options permit
1162 it for this host. */
1166 save_errno = ERRNO_TLSFAILURE;
1167 message = US"failure while setting up TLS session";
1172 /* TLS session is set up */
1174 for (addr = addrlist; addr != NULL; addr = addr->next)
1176 if (addr->transport_return == PENDING_DEFER)
1178 addr->cipher = tls_out.cipher;
1179 addr->peerdn = tls_out.peerdn;
1185 /* if smtps, we'll have smtp_command set to something else; always safe to
1187 smtp_command = big_buffer;
1189 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1190 helo_data is null, we are dealing with a connection that was passed from
1191 another process, and so we won't have expanded helo_data above. We have to
1192 expand it here. $sending_ip_address and $sending_port are set up right at the
1193 start of the Exim process (in exim.c). */
1195 if (tls_out.active >= 0)
1198 if (helo_data == NULL)
1200 helo_data = expand_string(ob->helo_data);
1201 if (helo_data == NULL)
1203 uschar *message = string_sprintf("failed to expand helo_data: %s",
1204 expand_string_message);
1205 set_errno(addrlist, 0, message, DEFER, FALSE);
1211 /* For SMTPS we need to wait for the initial OK response. */
1214 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1215 ob->command_timeout)) goto RESPONSE_FAILED;
1219 greeting_cmd = "EHLO";
1222 greeting_cmd = "HELO";
1224 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1227 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1228 lmtp? "LHLO" : greeting_cmd, helo_data) < 0)
1230 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1231 ob->command_timeout))
1232 goto RESPONSE_FAILED;
1235 /* If the host is required to use a secure channel, ensure that we
1238 else if (verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
1239 host->address, NULL) == OK)
1241 save_errno = ERRNO_TLSREQUIRED;
1242 message = string_sprintf("a TLS session is required for %s [%s], but %s",
1243 host->name, host->address,
1244 tls_offered? "an attempt to start TLS failed" :
1245 "the server did not offer TLS support");
1250 /* If TLS is active, we have just started it up and re-done the EHLO command,
1251 so its response needs to be analyzed. If TLS is not active and this is a
1252 continued session down a previously-used socket, we haven't just done EHLO, so
1255 if (continue_hostname == NULL
1257 || tls_out.active >= 0
1262 uschar *fail_reason = US"server did not advertise AUTH support";
1264 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
1265 lmtp_ignore_quota option was set. */
1267 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1268 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1269 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1271 /* If the response to EHLO specified support for the SIZE parameter, note
1272 this, provided size_addition is non-negative. */
1274 smtp_use_size = esmtp && ob->size_addition >= 0 &&
1275 pcre_exec(regex_SIZE, NULL, CS buffer, Ustrlen(CS buffer), 0,
1276 PCRE_EOPT, NULL, 0) >= 0;
1278 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
1279 the current host, esmtp will be false, so PIPELINING can never be used. If
1280 the current host matches hosts_avoid_pipelining, don't do it. */
1282 smtp_use_pipelining = esmtp &&
1283 verify_check_this_host(&(ob->hosts_avoid_pipelining), NULL, host->name,
1284 host->address, NULL) != OK &&
1285 pcre_exec(regex_PIPELINING, NULL, CS buffer, Ustrlen(CS buffer), 0,
1286 PCRE_EOPT, NULL, 0) >= 0;
1288 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
1289 smtp_use_pipelining? "" : "not ");
1291 #ifdef EXPERIMENTAL_PRDR
1292 prdr_offered = esmtp &&
1293 pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(CS buffer), 0,
1294 PCRE_EOPT, NULL, 0) >= 0 &&
1295 verify_check_this_host(&(ob->hosts_try_prdr), NULL, host->name,
1296 host->address, NULL) == OK;
1299 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1302 /* Note if the response to EHLO specifies support for the AUTH extension.
1303 If it has, check that this host is one we want to authenticate to, and do
1304 the business. The host name and address must be available when the
1305 authenticator's client driver is running. */
1307 smtp_authenticated = FALSE;
1308 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
1309 require_auth = verify_check_this_host(&(ob->hosts_require_auth), NULL,
1310 host->name, host->address, NULL);
1312 if (esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
1314 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
1315 expand_nmax = -1; /* reset */
1317 /* Must not do this check until after we have saved the result of the
1318 regex match above. */
1320 if (require_auth == OK ||
1321 verify_check_this_host(&(ob->hosts_try_auth), NULL, host->name,
1322 host->address, NULL) == OK)
1325 fail_reason = US"no common mechanisms were found";
1327 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1329 /* Scan the configured authenticators looking for one which is configured
1330 for use as a client, which is not suppressed by client_condition, and
1331 whose name matches an authentication mechanism supported by the server.
1332 If one is found, attempt to authenticate by calling its client function.
1335 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1339 (au->client_condition != NULL &&
1340 !expand_check_condition(au->client_condition, au->name,
1341 US"client authenticator")))
1343 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1345 (au->client)? "client_condition is false" :
1346 "not configured as a client");
1350 /* Loop to scan supported server mechanisms */
1355 int len = Ustrlen(au->public_name);
1356 while (isspace(*p)) p++;
1358 if (strncmpic(au->public_name, p, len) != 0 ||
1359 (p[len] != 0 && !isspace(p[len])))
1361 while (*p != 0 && !isspace(*p)) p++;
1365 /* Found data for a listed mechanism. Call its client entry. Set
1366 a flag in the outblock so that data is overwritten after sending so
1367 that reflections don't show it. */
1369 fail_reason = US"authentication attempt(s) failed";
1370 outblock.authenticating = TRUE;
1371 rc = (au->info->clientcode)(au, &inblock, &outblock,
1372 ob->command_timeout, buffer, sizeof(buffer));
1373 outblock.authenticating = FALSE;
1374 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1377 /* A temporary authentication failure must hold up delivery to
1378 this host. After a permanent authentication failure, we carry on
1379 to try other authentication methods. If all fail hard, try to
1380 deliver the message unauthenticated unless require_auth was set. */
1385 smtp_authenticated = TRUE; /* stops the outer loop */
1386 client_authenticator = au->name;
1387 if (au->set_client_id != NULL)
1388 client_authenticated_id = expand_string(au->set_client_id);
1391 /* Failure after writing a command */
1396 /* Failure after reading a response */
1399 if (errno != 0 || buffer[0] != '5') goto RESPONSE_FAILED;
1400 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1401 au->name, host->name, host->address, buffer);
1404 /* Failure by some other means. In effect, the authenticator
1405 decided it wasn't prepared to handle this case. Typically this
1406 is the result of "fail" in an expansion string. Do we need to
1407 log anything here? Feb 2006: a message is now put in the buffer
1408 if logging is required. */
1412 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1413 "authentication H=%s [%s] %s", au->name, host->name,
1414 host->address, buffer);
1417 /* Internal problem, message in buffer. */
1421 set_errno(addrlist, 0, string_copy(buffer), DEFER, FALSE);
1425 break; /* If not authenticated, try next authenticator */
1426 } /* Loop for scanning supported server mechanisms */
1427 } /* Loop for further authenticators */
1431 /* If we haven't authenticated, but are required to, give up. */
1433 if (require_auth == OK && !smtp_authenticated)
1436 set_errno(addrlist, ERRNO_AUTHFAIL,
1437 string_sprintf("authentication required but %s", fail_reason), DEFER,
1443 /* The setting up of the SMTP call is now complete. Any subsequent errors are
1444 message-specific. */
1448 /* If there is a filter command specified for this transport, we can now
1449 set it up. This cannot be done until the identify of the host is known. */
1451 if (tblock->filter_command != NULL)
1455 sprintf(CS buffer, "%.50s transport", tblock->name);
1456 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
1457 TRUE, DEFER, addrlist, buffer, NULL);
1458 transport_filter_timeout = tblock->filter_timeout;
1460 /* On failure, copy the error to all addresses, abandon the SMTP call, and
1465 set_errno(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
1473 /* For messages that have more than the maximum number of envelope recipients,
1474 we want to send several transactions down the same SMTP connection. (See
1475 comments in deliver.c as to how this reconciles, heuristically, with
1476 remote_max_parallel.) This optimization was added to Exim after the following
1477 code was already working. The simplest way to put it in without disturbing the
1478 code was to use a goto to jump back to this point when there is another
1479 transaction to handle. */
1482 sync_addr = first_addr;
1486 completed_address = FALSE;
1489 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
1490 qualification, send it, adding something to the message size to allow for
1491 imprecision and things that get added en route. Exim keeps the number of lines
1492 in a message, so we can give an accurate value for the original message, but we
1493 need some additional to handle added headers. (Double "." characters don't get
1494 included in the count.) */
1501 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
1505 #ifdef EXPERIMENTAL_PRDR
1506 prdr_active = FALSE;
1509 for (addr = first_addr; addr; addr = addr->next)
1510 if (addr->transport_return == PENDING_DEFER)
1512 for (addr = addr->next; addr; addr = addr->next)
1513 if (addr->transport_return == PENDING_DEFER)
1514 { /* at least two recipients to send */
1516 sprintf(CS p, " PRDR"); p += 5;
1517 goto prdr_is_active;
1525 /* If an authenticated_sender override has been specified for this transport
1526 instance, expand it. If the expansion is forced to fail, and there was already
1527 an authenticated_sender for this message, the original value will be used.
1528 Other expansion failures are serious. An empty result is ignored, but there is
1529 otherwise no check - this feature is expected to be used with LMTP and other
1530 cases where non-standard addresses (e.g. without domains) might be required. */
1532 if (ob->authenticated_sender != NULL)
1534 uschar *new = expand_string(ob->authenticated_sender);
1537 if (!expand_string_forcedfail)
1539 uschar *message = string_sprintf("failed to expand "
1540 "authenticated_sender: %s", expand_string_message);
1541 set_errno(addrlist, 0, message, DEFER, FALSE);
1545 else if (new[0] != 0) local_authenticated_sender = new;
1548 /* Add the authenticated sender address if present */
1550 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1551 local_authenticated_sender != NULL)
1553 string_format(p, sizeof(buffer) - (p-buffer), " AUTH=%s",
1554 auth_xtextencode(local_authenticated_sender,
1555 Ustrlen(local_authenticated_sender)));
1556 client_authenticated_sender = string_copy(local_authenticated_sender);
1559 /* From here until we send the DATA command, we can make use of PIPELINING
1560 if the server host supports it. The code has to be able to check the responses
1561 at any point, for when the buffer fills up, so we write it totally generally.
1562 When PIPELINING is off, each command written reports that it has flushed the
1565 pending_MAIL = TRUE; /* The block starts with MAIL */
1567 rc = smtp_write_command(&outblock, smtp_use_pipelining,
1568 "MAIL FROM:<%s>%s\r\n", return_path, buffer);
1569 mail_command = string_copy(big_buffer); /* Save for later error message */
1573 case -1: /* Transmission error */
1576 case +1: /* Block was sent */
1577 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1578 ob->command_timeout))
1580 if (errno == 0 && buffer[0] == '4')
1582 errno = ERRNO_MAIL4XX;
1583 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1585 goto RESPONSE_FAILED;
1587 pending_MAIL = FALSE;
1591 /* Pass over all the relevant recipient addresses for this host, which are the
1592 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
1593 several before we have to read the responses for those seen so far. This
1594 checking is done by a subroutine because it also needs to be done at the end.
1595 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
1596 the next one if not all are sent.
1598 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
1599 last address because we want to abort if any recipients have any kind of
1600 problem, temporary or permanent. We know that all recipient addresses will have
1601 the PENDING_DEFER status, because only one attempt is ever made, and we know
1602 that max_rcpt will be large, so all addresses will be done at once. */
1604 for (addr = first_addr;
1605 address_count < max_rcpt && addr != NULL;
1611 if (addr->transport_return != PENDING_DEFER) continue;
1614 no_flush = smtp_use_pipelining && (!mua_wrapper || addr->next != NULL);
1616 /* Now send the RCPT command, and process outstanding responses when
1617 necessary. After a timeout on RCPT, we just end the function, leaving the
1618 yield as OK, because this error can often mean that there is a problem with
1619 just one address, so we don't want to delay the host. */
1621 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s\r\n",
1622 transport_rcpt_address(addr, tblock->rcpt_include_affixes), igquotstr);
1623 if (count < 0) goto SEND_FAILED;
1626 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
1627 &sync_addr, host, count, ob->address_retry_include_sender,
1628 pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
1631 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1632 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1635 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1636 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1637 case 0: /* No 2xx or 5xx, but no probs */
1640 case -1: goto END_OFF; /* Timeout on RCPT */
1641 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
1643 pending_MAIL = FALSE; /* Dealt with MAIL */
1645 } /* Loop for next address */
1647 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
1648 permanently or temporarily. We should have flushed and synced after the last
1653 address_item *badaddr;
1654 for (badaddr = first_addr; badaddr != NULL; badaddr = badaddr->next)
1656 if (badaddr->transport_return != PENDING_OK) break;
1658 if (badaddr != NULL)
1660 set_errno(addrlist, 0, badaddr->message, FAIL,
1661 testflag(badaddr, af_pass_message));
1666 /* If ok is TRUE, we know we have got at least one good recipient, and must now
1667 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
1668 have a good recipient buffered up if we are pipelining. We don't want to waste
1669 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
1670 are pipelining. The responses are all handled by sync_responses(). */
1672 if (ok || (smtp_use_pipelining && !mua_wrapper))
1674 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
1675 if (count < 0) goto SEND_FAILED;
1676 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
1677 host, count, ob->address_retry_include_sender, pending_MAIL,
1678 ok? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
1680 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1681 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1684 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1685 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1686 case 0: break; /* No 2xx or 5xx, but no probs */
1688 case -1: goto END_OFF; /* Timeout on RCPT */
1689 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
1693 /* Save the first address of the next batch. */
1697 /* If there were no good recipients (but otherwise there have been no
1698 problems), just set ok TRUE, since we have handled address-specific errors
1699 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
1700 for handling the SMTP dot-handling protocol, flagging to apply to headers as
1701 well as body. Set the appropriate timeout value to be used for each chunk.
1702 (Haven't been able to make it work using select() for writing yet.) */
1704 if (!ok) ok = TRUE; else
1706 sigalrm_seen = FALSE;
1707 transport_write_timeout = ob->data_timeout;
1708 smtp_command = US"sending data block"; /* For error messages */
1709 DEBUG(D_transport|D_v)
1710 debug_printf(" SMTP>> writing message and terminating \".\"\n");
1711 transport_count = 0;
1712 #ifndef DISABLE_DKIM
1713 ok = dkim_transport_write_message(addrlist, inblock.sock,
1714 topt_use_crlf | topt_end_dot | topt_escape_headers |
1715 (tblock->body_only? topt_no_headers : 0) |
1716 (tblock->headers_only? topt_no_body : 0) |
1717 (tblock->return_path_add? topt_add_return_path : 0) |
1718 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1719 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1720 0, /* No size limit */
1721 tblock->add_headers, tblock->remove_headers,
1722 US".", US"..", /* Escaping strings */
1723 tblock->rewrite_rules, tblock->rewrite_existflags,
1724 ob->dkim_private_key, ob->dkim_domain, ob->dkim_selector,
1725 ob->dkim_canon, ob->dkim_strict, ob->dkim_sign_headers
1728 ok = transport_write_message(addrlist, inblock.sock,
1729 topt_use_crlf | topt_end_dot | topt_escape_headers |
1730 (tblock->body_only? topt_no_headers : 0) |
1731 (tblock->headers_only? topt_no_body : 0) |
1732 (tblock->return_path_add? topt_add_return_path : 0) |
1733 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1734 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1735 0, /* No size limit */
1736 tblock->add_headers, tblock->remove_headers,
1737 US".", US"..", /* Escaping strings */
1738 tblock->rewrite_rules, tblock->rewrite_existflags);
1741 /* transport_write_message() uses write() because it is called from other
1742 places to write to non-sockets. This means that under some OS (e.g. Solaris)
1743 it can exit with "Broken pipe" as its error. This really means that the
1744 socket got closed at the far end. */
1746 transport_write_timeout = 0; /* for subsequent transports */
1748 /* Failure can either be some kind of I/O disaster (including timeout),
1749 or the failure of a transport filter or the expansion of added headers. */
1753 buffer[0] = 0; /* There hasn't been a response */
1754 goto RESPONSE_FAILED;
1757 /* We used to send the terminating "." explicitly here, but because of
1758 buffering effects at both ends of TCP/IP connections, you don't gain
1759 anything by keeping it separate, so it might as well go in the final
1760 data buffer for efficiency. This is now done by setting the topt_end_dot
1763 smtp_command = US"end of data";
1765 #ifdef EXPERIMENTAL_PRDR
1766 /* For PRDR we optionally get a partial-responses warning
1767 * followed by the individual responses, before going on with
1768 * the overall response. If we don't get the warning then deal
1769 * with per non-PRDR. */
1772 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '3',
1774 if (!ok && errno == 0)
1777 case '2': prdr_active = FALSE;
1780 case '4': errno = ERRNO_DATA4XX;
1781 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1788 /* For non-PRDR SMTP, we now read a single response that applies to the
1789 whole message. If it is OK, then all the addresses have been delivered. */
1793 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1795 if (!ok && errno == 0 && buffer[0] == '4')
1797 errno = ERRNO_DATA4XX;
1798 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1802 /* For LMTP, we get back a response for every RCPT command that we sent;
1803 some may be accepted and some rejected. For those that get a response, their
1804 status is fixed; any that are accepted have been handed over, even if later
1805 responses crash - at least, that's how I read RFC 2033.
1807 If all went well, mark the recipient addresses as completed, record which
1808 host/IPaddress they were delivered to, and cut out RSET when sending another
1809 message down the same channel. Write the completed addresses to the journal
1810 now so that they are recorded in case there is a crash of hardware or
1811 software before the spool gets updated. Also record the final SMTP
1812 confirmation if needed (for SMTP only). */
1817 int delivery_time = (int)(time(NULL) - start_delivery_time);
1820 uschar *conf = NULL;
1823 /* Make a copy of the host if it is local to this invocation
1824 of the transport. */
1828 thost = store_get(sizeof(host_item));
1830 thost->name = string_copy(host->name);
1831 thost->address = string_copy(host->address);
1835 /* Set up confirmation if needed - applies only to SMTP */
1837 if ((log_extra_selector & LX_smtp_confirmation) != 0 && !lmtp)
1839 uschar *s = string_printing(buffer);
1840 conf = (s == buffer)? (uschar *)string_copy(s) : s;
1843 /* Process all transported addresses - for LMTP or PRDR, read a status for
1846 for (addr = addrlist; addr != first_addr; addr = addr->next)
1848 if (addr->transport_return != PENDING_OK) continue;
1850 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
1851 remaining addresses. Otherwise, it's a return code for just the one
1852 address. For temporary errors, add a retry item for the address so that
1853 it doesn't get tried again too soon. */
1855 #ifdef EXPERIMENTAL_PRDR
1856 if (lmtp || prdr_active)
1861 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1864 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
1865 addr->message = string_sprintf(
1866 #ifdef EXPERIMENTAL_PRDR
1867 "%s error after %s: %s", prdr_active ? "PRDR":"LMTP",
1869 "LMTP error after %s: %s",
1871 big_buffer, string_printing(buffer));
1872 setflag(addr, af_pass_message); /* Allow message to go to user */
1873 if (buffer[0] == '5')
1874 addr->transport_return = FAIL;
1877 errno = ERRNO_DATA4XX;
1878 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1879 addr->transport_return = DEFER;
1880 #ifdef EXPERIMENTAL_PRDR
1883 retry_add_item(addr, addr->address_retry_key, 0);
1887 completed_address = TRUE; /* NOW we can set this flag */
1888 if ((log_extra_selector & LX_smtp_confirmation) != 0)
1890 uschar *s = string_printing(buffer);
1891 conf = (s == buffer)? (uschar *)string_copy(s) : s;
1895 /* SMTP, or success return from LMTP for this address. Pass back the
1896 actual host that was used. */
1898 addr->transport_return = OK;
1899 addr->more_errno = delivery_time;
1900 addr->host_used = thost;
1901 addr->special_action = flag;
1902 addr->message = conf;
1903 #ifdef EXPERIMENTAL_PRDR
1904 if (prdr_active) addr->flags |= af_prdr_used;
1908 #ifdef EXPERIMENTAL_PRDR
1912 /* Update the journal. For homonymic addresses, use the base address plus
1913 the transport name. See lots of comments in deliver.c about the reasons
1914 for the complications when homonyms are involved. Just carry on after
1915 write error, as it may prove possible to update the spool file later. */
1917 if (testflag(addr, af_homonym))
1918 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
1920 sprintf(CS buffer, "%.500s\n", addr->unique);
1922 DEBUG(D_deliver) debug_printf("journalling %s", buffer);
1923 len = Ustrlen(CS buffer);
1924 if (write(journal_fd, buffer, len) != len)
1925 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
1926 "%s: %s", buffer, strerror(errno));
1930 #ifdef EXPERIMENTAL_PRDR
1933 /* PRDR - get the final, overall response. For any non-success
1934 upgrade all the address statuses. */
1935 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1939 if(errno == 0 && buffer[0] == '4')
1941 errno = ERRNO_DATA4XX;
1942 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1944 for (addr = addrlist; addr != first_addr; addr = addr->next)
1945 if (buffer[0] == '5' || addr->transport_return == OK)
1946 addr->transport_return = PENDING_OK; /* allow set_errno action */
1947 goto RESPONSE_FAILED;
1950 /* Update the journal, or setup retry. */
1951 for (addr = addrlist; addr != first_addr; addr = addr->next)
1952 if (addr->transport_return == OK)
1954 if (testflag(addr, af_homonym))
1955 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
1957 sprintf(CS buffer, "%.500s\n", addr->unique);
1959 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s", buffer);
1960 len = Ustrlen(CS buffer);
1961 if (write(journal_fd, buffer, len) != len)
1962 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
1963 "%s: %s", buffer, strerror(errno));
1965 else if (addr->transport_return == DEFER)
1966 retry_add_item(addr, addr->address_retry_key, -2);
1970 /* Ensure the journal file is pushed out to disk. */
1972 if (EXIMfsync(journal_fd) < 0)
1973 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
1979 /* Handle general (not specific to one address) failures here. The value of ok
1980 is used to skip over this code on the falling through case. A timeout causes a
1981 deferral. Other errors may defer or fail according to the response code, and
1982 may set up a special errno value, e.g. after connection chopped, which is
1983 assumed if errno == 0 and there is no text in the buffer. If control reaches
1984 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
1985 the problem is not related to this specific message. */
1994 send_quit = check_response(host, &save_errno, addrlist->more_errno,
1995 buffer, &code, &message, &pass_message);
2001 message = US string_sprintf("send() to %s [%s] failed: %s",
2002 host->name, host->address, strerror(save_errno));
2006 /* This label is jumped to directly when a TLS negotiation has failed,
2007 or was not done for a host for which it is required. Values will be set
2008 in message and save_errno, and setting_up will always be true. Treat as
2009 a temporary error. */
2016 /* If the failure happened while setting up the call, see if the failure was
2017 a 5xx response (this will either be on connection, or following HELO - a 5xx
2018 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
2019 never going to accept them. For other errors during setting up (timeouts or
2020 whatever), defer all addresses, and yield DEFER, so that the host is not
2021 tried again for a while. */
2024 ok = FALSE; /* For when reached by GOTO */
2030 set_errno(addrlist, save_errno, message, FAIL, pass_message);
2034 set_errno(addrlist, save_errno, message, DEFER, pass_message);
2039 /* We want to handle timeouts after MAIL or "." and loss of connection after
2040 "." specially. They can indicate a problem with the sender address or with
2041 the contents of the message rather than a real error on the connection. These
2042 cases are treated in the same way as a 4xx response. This next bit of code
2043 does the classification. */
2054 message_error = TRUE;
2058 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
2059 Ustrncmp(smtp_command,"end ",4) == 0;
2062 case ERRNO_SMTPCLOSED:
2063 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
2067 message_error = FALSE;
2071 /* Handle the cases that are treated as message errors. These are:
2073 (a) negative response or timeout after MAIL
2074 (b) negative response after DATA
2075 (c) negative response or timeout or dropped connection after "."
2077 It won't be a negative response or timeout after RCPT, as that is dealt
2078 with separately above. The action in all cases is to set an appropriate
2079 error code for all the addresses, but to leave yield set to OK because the
2080 host itself has not failed. Of course, it might in practice have failed
2081 when we've had a timeout, but if so, we'll discover that at the next
2082 delivery attempt. For a temporary error, set the message_defer flag, and
2083 write to the logs for information if this is not the last host. The error
2084 for the last host will be logged as part of the address's log line. */
2088 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
2089 set_errno(addrlist, save_errno, message, (code == '5')? FAIL : DEFER,
2092 /* If there's an errno, the message contains just the identity of
2095 if (code != '5') /* Anything other than 5 is treated as temporary */
2098 message = US string_sprintf("%s: %s", message, strerror(save_errno));
2099 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
2100 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
2101 *message_defer = TRUE;
2105 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
2106 ".", or some other transportation error. We defer all addresses and yield
2107 DEFER, except for the case of failed add_headers expansion, or a transport
2108 filter failure, when the yield should be ERROR, to stop it trying other
2113 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
2114 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
2115 set_errno(addrlist, save_errno, message, DEFER, pass_message);
2121 /* If all has gone well, send_quit will be set TRUE, implying we can end the
2122 SMTP session tidily. However, if there were too many addresses to send in one
2123 message (indicated by first_addr being non-NULL) we want to carry on with the
2124 rest of them. Also, it is desirable to send more than one message down the SMTP
2125 connection if there are several waiting, provided we haven't already sent so
2126 many as to hit the configured limit. The function transport_check_waiting looks
2127 for a waiting message and returns its id. Then transport_pass_socket tries to
2128 set up a continued delivery by passing the socket on to another process. The
2129 variable send_rset is FALSE if a message has just been successfully transfered.
2131 If we are already sending down a continued channel, there may be further
2132 addresses not yet delivered that are aimed at the same host, but which have not
2133 been passed in this run of the transport. In this case, continue_more will be
2134 true, and all we should do is send RSET if necessary, and return, leaving the
2137 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
2138 do not want to continue with other messages down the same channel, because that
2139 can lead to looping between two or more messages, all with the same,
2140 temporarily failing address(es). [The retry information isn't updated yet, so
2141 new processes keep on trying.] We probably also don't want to try more of this
2142 message's addresses either.
2144 If we have started a TLS session, we have to end it before passing the
2145 connection to a new process. However, not all servers can handle this (Exim
2146 can), so we do not pass such a connection on if the host matches
2147 hosts_nopass_tls. */
2150 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
2151 "yield=%d first_address is %sNULL\n", ok, send_quit, send_rset,
2152 continue_more, yield, (first_addr == NULL)? "":"not ");
2154 if (completed_address && ok && send_quit)
2157 if (first_addr != NULL || continue_more ||
2159 (tls_out.active < 0 ||
2160 verify_check_this_host(&(ob->hosts_nopass_tls), NULL, host->name,
2161 host->address, NULL) != OK)
2163 transport_check_waiting(tblock->name, host->name,
2164 tblock->connection_max_messages, new_message_id, &more)
2172 if (! (ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
2174 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
2175 host->address, strerror(save_errno));
2178 else if (! (ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2179 ob->command_timeout)))
2182 send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
2186 DEBUG(D_transport) debug_printf("%s\n", msg);
2191 /* Either RSET was not needed, or it succeeded */
2195 if (first_addr != NULL) /* More addresses still to be sent */
2196 { /* in this run of the transport */
2197 continue_sequence++; /* Causes * in logging */
2200 if (continue_more) return yield; /* More addresses for another run */
2202 /* Pass the socket to a new Exim process. Before doing so, we must shut
2203 down TLS. Not all MTAs allow for the continuation of the SMTP session
2204 when TLS is shut down. We test for this by sending a new EHLO. If we
2205 don't get a good response, we don't attempt to pass the socket on. */
2208 if (tls_out.active >= 0)
2210 tls_close(FALSE, TRUE);
2214 ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
2215 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2216 ob->command_timeout);
2220 /* If the socket is successfully passed, we musn't send QUIT (or
2221 indeed anything!) from here. */
2223 if (ok && transport_pass_socket(tblock->name, host->name, host->address,
2224 new_message_id, inblock.sock))
2230 /* If RSET failed and there are addresses left, they get deferred. */
2232 else set_errno(first_addr, errno, msg, DEFER, FALSE);
2236 /* End off tidily with QUIT unless the connection has died or the socket has
2237 been passed to another process. There has been discussion on the net about what
2238 to do after sending QUIT. The wording of the RFC suggests that it is necessary
2239 to wait for a response, but on the other hand, there isn't anything one can do
2240 with an error response, other than log it. Exim used to do that. However,
2241 further discussion suggested that it is positively advantageous not to wait for
2242 the response, but to close the session immediately. This is supposed to move
2243 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
2244 load from the server. (Hosts that are both servers and clients may not see much
2245 difference, of course.) Further discussion indicated that this was safe to do
2246 on Unix systems which have decent implementations of TCP/IP that leave the
2247 connection around for a while (TIME_WAIT) after the application has gone away.
2248 This enables the response sent by the server to be properly ACKed rather than
2249 timed out, as can happen on broken TCP/IP implementations on other OS.
2251 This change is being made on 31-Jul-98. After over a year of trouble-free
2252 operation, the old commented-out code was removed on 17-Sep-99. */
2255 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2260 tls_close(FALSE, TRUE);
2263 /* Close the socket, and return the appropriate value, first setting
2264 continue_transport and continue_hostname NULL to prevent any other addresses
2265 that may include the host from trying to re-use a continuation socket. This
2266 works because the NULL setting is passed back to the calling process, and
2267 remote_max_parallel is forced to 1 when delivering over an existing connection,
2269 If all went well and continue_more is set, we shouldn't actually get here if
2270 there are further addresses, as the return above will be taken. However,
2271 writing RSET might have failed, or there may be other addresses whose hosts are
2272 specified in the transports, and therefore not visible at top level, in which
2273 case continue_more won't get set. */
2275 (void)close(inblock.sock);
2276 continue_transport = NULL;
2277 continue_hostname = NULL;
2284 /*************************************************
2285 * Closedown entry point *
2286 *************************************************/
2288 /* This function is called when exim is passed an open smtp channel
2289 from another incarnation, but the message which it has been asked
2290 to deliver no longer exists. The channel is on stdin.
2292 We might do fancy things like looking for another message to send down
2293 the channel, but if the one we sought has gone, it has probably been
2294 delivered by some other process that itself will seek further messages,
2295 so just close down our connection.
2297 Argument: pointer to the transport instance block
2302 smtp_transport_closedown(transport_instance *tblock)
2304 smtp_transport_options_block *ob =
2305 (smtp_transport_options_block *)(tblock->options_block);
2306 smtp_inblock inblock;
2307 smtp_outblock outblock;
2309 uschar inbuffer[4096];
2310 uschar outbuffer[16];
2312 inblock.sock = fileno(stdin);
2313 inblock.buffer = inbuffer;
2314 inblock.buffersize = sizeof(inbuffer);
2315 inblock.ptr = inbuffer;
2316 inblock.ptrend = inbuffer;
2318 outblock.sock = inblock.sock;
2319 outblock.buffersize = sizeof(outbuffer);
2320 outblock.buffer = outbuffer;
2321 outblock.ptr = outbuffer;
2322 outblock.cmd_count = 0;
2323 outblock.authenticating = FALSE;
2325 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2326 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2327 ob->command_timeout);
2328 (void)close(inblock.sock);
2333 /*************************************************
2334 * Prepare addresses for delivery *
2335 *************************************************/
2337 /* This function is called to flush out error settings from previous delivery
2338 attempts to other hosts. It also records whether we got here via an MX record
2339 or not in the more_errno field of the address. We are interested only in
2340 addresses that are still marked DEFER - others may have got delivered to a
2341 previously considered IP address. Set their status to PENDING_DEFER to indicate
2342 which ones are relevant this time.
2345 addrlist the list of addresses
2346 host the host we are delivering to
2348 Returns: the first address for this delivery
2351 static address_item *
2352 prepare_addresses(address_item *addrlist, host_item *host)
2354 address_item *first_addr = NULL;
2356 for (addr = addrlist; addr != NULL; addr = addr->next)
2358 if (addr->transport_return != DEFER) continue;
2359 if (first_addr == NULL) first_addr = addr;
2360 addr->transport_return = PENDING_DEFER;
2361 addr->basic_errno = 0;
2362 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
2363 addr->message = NULL;
2365 addr->cipher = NULL;
2366 addr->peerdn = NULL;
2374 /*************************************************
2375 * Main entry point *
2376 *************************************************/
2378 /* See local README for interface details. As this is a remote transport, it is
2379 given a chain of addresses to be delivered in one connection, if possible. It
2380 always returns TRUE, indicating that each address has its own independent
2381 status set, except if there is a setting up problem, in which case it returns
2385 smtp_transport_entry(
2386 transport_instance *tblock, /* data for this instantiation */
2387 address_item *addrlist) /* addresses we are working on */
2391 int hosts_defer = 0;
2393 int hosts_looked_up = 0;
2394 int hosts_retry = 0;
2395 int hosts_serial = 0;
2396 int hosts_total = 0;
2397 int total_hosts_tried = 0;
2399 BOOL expired = TRUE;
2400 BOOL continuing = continue_hostname != NULL;
2401 uschar *expanded_hosts = NULL;
2403 uschar *tid = string_sprintf("%s transport", tblock->name);
2404 smtp_transport_options_block *ob =
2405 (smtp_transport_options_block *)(tblock->options_block);
2406 host_item *hostlist = addrlist->host_list;
2407 host_item *host = NULL;
2411 debug_printf("%s transport entered\n", tblock->name);
2412 for (addr = addrlist; addr != NULL; addr = addr->next)
2413 debug_printf(" %s\n", addr->address);
2414 if (continuing) debug_printf("already connected to %s [%s]\n",
2415 continue_hostname, continue_host_address);
2418 /* Set the flag requesting that these hosts be added to the waiting
2419 database if the delivery fails temporarily or if we are running with
2420 queue_smtp or a 2-stage queue run. This gets unset for certain
2421 kinds of error, typically those that are specific to the message. */
2423 update_waiting = TRUE;
2425 /* If a host list is not defined for the addresses - they must all have the
2426 same one in order to be passed to a single transport - or if the transport has
2427 a host list with hosts_override set, use the host list supplied with the
2428 transport. It is an error for this not to exist. */
2430 if (hostlist == NULL || (ob->hosts_override && ob->hosts != NULL))
2432 if (ob->hosts == NULL)
2434 addrlist->message = string_sprintf("%s transport called with no hosts set",
2436 addrlist->transport_return = PANIC;
2437 return FALSE; /* Only top address has status */
2440 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
2443 /* If the transport's host list contains no '$' characters, and we are not
2444 randomizing, it is fixed and therefore a chain of hosts can be built once
2445 and for all, and remembered for subsequent use by other calls to this
2446 transport. If, on the other hand, the host list does contain '$', or we are
2447 randomizing its order, we have to rebuild it each time. In the fixed case,
2448 as the hosts string will never be used again, it doesn't matter that we
2449 replace all the : characters with zeros. */
2451 if (ob->hostlist == NULL)
2453 uschar *s = ob->hosts;
2455 if (Ustrchr(s, '$') != NULL)
2457 expanded_hosts = expand_string(s);
2458 if (expanded_hosts == NULL)
2460 addrlist->message = string_sprintf("failed to expand list of hosts "
2461 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
2462 addrlist->transport_return = search_find_defer? DEFER : PANIC;
2463 return FALSE; /* Only top address has status */
2465 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
2466 "\"%s\"\n", s, expanded_hosts);
2470 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
2472 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
2474 /* Check that the expansion yielded something useful. */
2475 if (hostlist == NULL)
2478 string_sprintf("%s transport has empty hosts setting", tblock->name);
2479 addrlist->transport_return = PANIC;
2480 return FALSE; /* Only top address has status */
2483 /* If there was no expansion of hosts, save the host list for
2486 if (expanded_hosts == NULL) ob->hostlist = hostlist;
2489 /* This is not the first time this transport has been run in this delivery;
2490 the host list was built previously. */
2492 else hostlist = ob->hostlist;
2495 /* The host list was supplied with the address. If hosts_randomize is set, we
2496 must sort it into a random order if it did not come from MX records and has not
2497 already been randomized (but don't bother if continuing down an existing
2500 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continuing)
2502 host_item *newlist = NULL;
2503 while (hostlist != NULL)
2505 host_item *h = hostlist;
2506 hostlist = hostlist->next;
2508 h->sort_key = random_number(100);
2510 if (newlist == NULL)
2515 else if (h->sort_key < newlist->sort_key)
2522 host_item *hh = newlist;
2523 while (hh->next != NULL)
2525 if (h->sort_key < hh->next->sort_key) break;
2533 hostlist = addrlist->host_list = newlist;
2537 /* Sort out the default port. */
2539 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
2542 /* For each host-plus-IP-address on the list:
2544 . If this is a continued delivery and the host isn't the one with the
2545 current connection, skip.
2547 . If the status is unusable (i.e. previously failed or retry checked), skip.
2549 . If no IP address set, get the address, either by turning the name into
2550 an address, calling gethostbyname if gethostbyname is on, or by calling
2551 the DNS. The DNS may yield multiple addresses, in which case insert the
2552 extra ones into the list.
2554 . Get the retry data if not previously obtained for this address and set the
2555 field which remembers the state of this address. Skip if the retry time is
2556 not reached. If not, remember whether retry data was found. The retry string
2557 contains both the name and the IP address.
2559 . Scan the list of addresses and mark those whose status is DEFER as
2560 PENDING_DEFER. These are the only ones that will be processed in this cycle
2563 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
2564 Some addresses may be successfully delivered, others may fail, and yet
2565 others may get temporary errors and so get marked DEFER.
2567 . The return from the delivery attempt is OK if a connection was made and a
2568 valid SMTP dialogue was completed. Otherwise it is DEFER.
2570 . If OK, add a "remove" retry item for this host/IPaddress, if any.
2572 . If fail to connect, or other defer state, add a retry item.
2574 . If there are any addresses whose status is still DEFER, carry on to the
2575 next host/IPaddress, unless we have tried the number of hosts given
2576 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
2577 there is some fancy logic for hosts_max_try that means its limit can be
2578 overstepped in some circumstances.
2580 If we get to the end of the list, all hosts have deferred at least one address,
2581 or not reached their retry times. If delay_after_cutoff is unset, it requests a
2582 delivery attempt to those hosts whose last try was before the arrival time of
2583 the current message. To cope with this, we have to go round the loop a second
2584 time. After that, set the status and error data for any addresses that haven't
2585 had it set already. */
2587 for (cutoff_retry = 0; expired &&
2588 cutoff_retry < ((ob->delay_after_cutoff)? 1 : 2);
2591 host_item *nexthost = NULL;
2592 int unexpired_hosts_tried = 0;
2594 for (host = hostlist;
2596 unexpired_hosts_tried < ob->hosts_max_try &&
2597 total_hosts_tried < ob->hosts_max_try_hardlimit;
2603 BOOL serialized = FALSE;
2604 BOOL host_is_expired = FALSE;
2605 BOOL message_defer = FALSE;
2606 BOOL ifchanges = FALSE;
2607 BOOL some_deferred = FALSE;
2608 address_item *first_addr = NULL;
2609 uschar *interface = NULL;
2610 uschar *retry_host_key = NULL;
2611 uschar *retry_message_key = NULL;
2612 uschar *serialize_key = NULL;
2614 /* Default next host is next host. :-) But this can vary if the
2615 hosts_max_try limit is hit (see below). It may also be reset if a host
2616 address is looked up here (in case the host was multihomed). */
2618 nexthost = host->next;
2620 /* If the address hasn't yet been obtained from the host name, look it up
2621 now, unless the host is already marked as unusable. If it is marked as
2622 unusable, it means that the router was unable to find its IP address (in
2623 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
2624 the lookup failed last time. We don't get this far if *all* MX records
2625 point to non-existent hosts; that is treated as a hard error.
2627 We can just skip this host entirely. When the hosts came from the router,
2628 the address will timeout based on the other host(s); when the address is
2629 looked up below, there is an explicit retry record added.
2631 Note that we mustn't skip unusable hosts if the address is not unset; they
2632 may be needed as expired hosts on the 2nd time round the cutoff loop. */
2634 if (host->address == NULL)
2636 int new_port, flags;
2638 uschar *canonical_name;
2640 if (host->status >= hstatus_unusable)
2642 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
2647 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
2649 /* The host name is permitted to have an attached port. Find it, and
2650 strip it from the name. Just remember it for now. */
2652 new_port = host_item_get_port(host);
2654 /* Count hosts looked up */
2658 /* Find by name if so configured, or if it's an IP address. We don't
2659 just copy the IP address, because we need the test-for-local to happen. */
2661 flags = HOST_FIND_BY_A;
2662 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
2663 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
2665 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
2666 rc = host_find_byname(host, NULL, flags, &canonical_name, TRUE);
2668 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
2669 &canonical_name, NULL);
2671 /* Update the host (and any additional blocks, resulting from
2672 multihoming) with a host-specific port, if any. */
2674 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
2676 /* Failure to find the host at this time (usually DNS temporary failure)
2677 is really a kind of routing failure rather than a transport failure.
2678 Therefore we add a retry item of the routing kind, not to stop us trying
2679 to look this name up here again, but to ensure the address gets timed
2680 out if the failures go on long enough. A complete failure at this point
2681 commonly points to a configuration error, but the best action is still
2682 to carry on for the next host. */
2684 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
2686 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
2688 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
2689 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
2690 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
2691 host->status = hstatus_unusable;
2693 for (addr = addrlist; addr != NULL; addr = addr->next)
2695 if (addr->transport_return != DEFER) continue;
2696 addr->basic_errno = ERRNO_UNKNOWNHOST;
2698 string_sprintf("failed to lookup IP address for %s", host->name);
2703 /* If the host is actually the local host, we may have a problem, or
2704 there may be some cunning configuration going on. In the problem case,
2705 log things and give up. The default transport status is already DEFER. */
2707 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
2709 for (addr = addrlist; addr != NULL; addr = addr->next)
2711 addr->basic_errno = 0;
2712 addr->message = string_sprintf("%s transport found host %s to be "
2713 "local", tblock->name, host->name);
2717 } /* End of block for IP address lookup */
2719 /* If this is a continued delivery, we are interested only in the host
2720 which matches the name of the existing open channel. The check is put
2721 here after the local host lookup, in case the name gets expanded as a
2722 result of the lookup. Set expired FALSE, to save the outer loop executing
2725 if (continuing && (Ustrcmp(continue_hostname, host->name) != 0 ||
2726 Ustrcmp(continue_host_address, host->address) != 0))
2729 continue; /* With next host */
2732 /* Reset the default next host in case a multihomed host whose addresses
2733 are not looked up till just above added to the host list. */
2735 nexthost = host->next;
2737 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
2738 domain is in queue_smtp_domains, we don't actually want to attempt any
2739 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
2740 there is a lookup defer in queue_smtp_domains, proceed as if the domain
2741 were not in it. We don't want to hold up all SMTP deliveries! Except when
2742 doing a two-stage queue run, don't do this if forcing. */
2744 if ((!deliver_force || queue_2stage) && (queue_smtp ||
2745 match_isinlist(addrlist->domain, &queue_smtp_domains, 0,
2746 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
2749 for (addr = addrlist; addr != NULL; addr = addr->next)
2751 if (addr->transport_return != DEFER) continue;
2752 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
2754 continue; /* With next host */
2757 /* Count hosts being considered - purely for an intelligent comment
2758 if none are usable. */
2762 /* Set $host and $host address now in case they are needed for the
2763 interface expansion or the serialize_hosts check; they remain set if an
2764 actual delivery happens. */
2766 deliver_host = host->name;
2767 deliver_host_address = host->address;
2769 /* Set up a string for adding to the retry key if the port number is not
2770 the standard SMTP port. A host may have its own port setting that overrides
2773 pistring = string_sprintf(":%d", (host->port == PORT_NONE)?
2775 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
2777 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
2778 string changes upon expansion, we must add it to the key that is used for
2779 retries, because connections to the same host from a different interface
2780 should be treated separately. */
2782 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET : AF_INET6;
2783 if (!smtp_get_interface(ob->interface, host_af, addrlist, &ifchanges,
2786 if (ifchanges) pistring = string_sprintf("%s/%s", pistring, interface);
2788 /* The first time round the outer loop, check the status of the host by
2789 inspecting the retry data. The second time round, we are interested only
2790 in expired hosts that haven't been tried since this message arrived. */
2792 if (cutoff_retry == 0)
2794 /* Ensure the status of the address is set by checking retry data if
2795 necessary. There maybe host-specific retry data (applicable to all
2796 messages) and also data for retries of a specific message at this host.
2797 If either of these retry records are actually read, the keys used are
2798 returned to save recomputing them later. */
2800 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
2801 ob->retry_include_ip_address, &retry_host_key, &retry_message_key);
2803 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
2804 (host->address == NULL)? US"" : host->address, pistring,
2805 (host->status == hstatus_usable)? "usable" :
2806 (host->status == hstatus_unusable)? "unusable" :
2807 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
2809 /* Skip this address if not usable at this time, noting if it wasn't
2810 actually expired, both locally and in the address. */
2812 switch (host->status)
2814 case hstatus_unusable:
2816 setflag(addrlist, af_retry_skipped);
2819 case hstatus_unusable_expired:
2822 case hwhy_retry: hosts_retry++; break;
2823 case hwhy_failed: hosts_fail++; break;
2824 case hwhy_deferred: hosts_defer++; break;
2827 /* If there was a retry message key, implying that previously there
2828 was a message-specific defer, we don't want to update the list of
2829 messages waiting for these hosts. */
2831 if (retry_message_key != NULL) update_waiting = FALSE;
2832 continue; /* With the next host or IP address */
2836 /* Second time round the loop: if the address is set but expired, and
2837 the message is newer than the last try, let it through. */
2841 if (host->address == NULL ||
2842 host->status != hstatus_unusable_expired ||
2843 host->last_try > received_time)
2846 debug_printf("trying expired host %s [%s]%s\n",
2847 host->name, host->address, pistring);
2848 host_is_expired = TRUE;
2851 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
2852 it remains TRUE only if all hosts are expired and none are actually tried.
2857 /* If this host is listed as one to which access must be serialized,
2858 see if another Exim process has a connection to it, and if so, skip
2859 this host. If not, update the database to record our connection to it
2860 and remember this for later deletion. Do not do any of this if we are
2861 sending the message down a pre-existing connection. */
2864 verify_check_this_host(&(ob->serialize_hosts), NULL, host->name,
2865 host->address, NULL) == OK)
2867 serialize_key = string_sprintf("host-serialize-%s", host->name);
2868 if (!enq_start(serialize_key))
2871 debug_printf("skipping host %s because another Exim process "
2872 "is connected to it\n", host->name);
2879 /* OK, we have an IP address that is not waiting for its retry time to
2880 arrive (it might be expired) OR (second time round the loop) we have an
2881 expired host that hasn't been tried since the message arrived. Have a go
2882 at delivering the message to it. First prepare the addresses by flushing
2883 out the result of previous attempts, and finding the first address that
2884 is still to be delivered. */
2886 first_addr = prepare_addresses(addrlist, host);
2888 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
2889 message_id, host->name, host->address, addrlist->address,
2890 (addrlist->next == NULL)? "" : ", ...");
2892 set_process_info("delivering %s to %s [%s] (%s%s)",
2893 message_id, host->name, host->address, addrlist->address,
2894 (addrlist->next == NULL)? "" : ", ...");
2896 /* This is not for real; don't do the delivery. If there are
2897 any remaining hosts, list them. */
2902 set_errno(addrlist, 0, NULL, OK, FALSE);
2903 for (addr = addrlist; addr != NULL; addr = addr->next)
2905 addr->host_used = host;
2906 addr->special_action = '*';
2907 addr->message = US"delivery bypassed by -N option";
2911 debug_printf("*** delivery by %s transport bypassed by -N option\n"
2912 "*** host and remaining hosts:\n", tblock->name);
2913 for (host2 = host; host2 != NULL; host2 = host2->next)
2914 debug_printf(" %s [%s]\n", host2->name,
2915 (host2->address == NULL)? US"unset" : host2->address);
2920 /* This is for real. If the host is expired, we don't count it for
2921 hosts_max_retry. This ensures that all hosts must expire before an address
2922 is timed out, unless hosts_max_try_hardlimit (which protects against
2923 lunatic DNS configurations) is reached.
2925 If the host is not expired and we are about to hit the hosts_max_retry
2926 limit, check to see if there is a subsequent hosts with a different MX
2927 value. If so, make that the next host, and don't count this one. This is a
2928 heuristic to make sure that different MXs do get tried. With a normal kind
2929 of retry rule, they would get tried anyway when the earlier hosts were
2930 delayed, but if the domain has a "retry every time" type of rule - as is
2931 often used for the the very large ISPs, that won't happen. */
2935 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
2939 debug_printf("hosts_max_try limit reached with this host\n");
2940 for (h = host; h != NULL; h = h->next)
2941 if (h->mx != host->mx) break;
2945 unexpired_hosts_tried--;
2946 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
2947 "and will be tried\n");
2951 /* Attempt the delivery. */
2953 total_hosts_tried++;
2954 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
2955 expanded_hosts != NULL, &message_defer, FALSE);
2958 OK => connection made, each address contains its result;
2959 message_defer is set for message-specific defers (when all
2960 recipients are marked defer)
2961 DEFER => there was a non-message-specific delivery problem;
2962 ERROR => there was a problem setting up the arguments for a filter,
2963 or there was a problem with expanding added headers
2966 /* If the result is not OK, there was a non-message-specific problem.
2967 If the result is DEFER, we need to write to the logs saying what happened
2968 for this particular host, except in the case of authentication and TLS
2969 failures, where the log has already been written. If all hosts defer a
2970 general message is written at the end. */
2972 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL &&
2973 first_addr->basic_errno != ERRNO_TLSFAILURE)
2974 write_logs(first_addr, host);
2976 /* If STARTTLS was accepted, but there was a failure in setting up the
2977 TLS session (usually a certificate screwup), and the host is not in
2978 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
2979 TLS forcibly turned off. We have to start from scratch with a new SMTP
2980 connection. That's why the retry is done from here, not from within
2981 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
2982 session, so the in-clear transmission after those errors, if permitted,
2983 happens inside smtp_deliver().] */
2986 if (rc == DEFER && first_addr->basic_errno == ERRNO_TLSFAILURE &&
2987 ob->tls_tempfail_tryclear &&
2988 verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
2989 host->address, NULL) != OK)
2991 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
2992 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
2993 first_addr = prepare_addresses(addrlist, host);
2994 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
2995 expanded_hosts != NULL, &message_defer, TRUE);
2996 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
2997 write_logs(first_addr, host);
3002 /* Delivery attempt finished */
3004 rs = (rc == OK)? US"OK" : (rc == DEFER)? US"DEFER" : (rc == ERROR)?
3007 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
3008 message_id, host->name, host->address, addrlist->address,
3009 (addrlist->next == NULL)? "" : " (& others)", rs);
3011 /* Release serialization if set up */
3013 if (serialized) enq_end(serialize_key);
3015 /* If the result is DEFER, or if a host retry record is known to exist, we
3016 need to add an item to the retry chain for updating the retry database
3017 at the end of delivery. We only need to add the item to the top address,
3018 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
3019 for any other delivery attempts using the same address. (It is copied into
3020 the unusable tree at the outer level, so even if different address blocks
3021 contain the same address, it still won't get tried again.) */
3023 if (rc == DEFER || retry_host_key != NULL)
3025 int delete_flag = (rc != DEFER)? rf_delete : 0;
3026 if (retry_host_key == NULL)
3028 retry_host_key = ob->retry_include_ip_address?
3029 string_sprintf("T:%S:%s%s", host->name, host->address, pistring) :
3030 string_sprintf("T:%S%s", host->name, pistring);
3033 /* If a delivery of another message over an existing SMTP connection
3034 yields DEFER, we do NOT set up retry data for the host. This covers the
3035 case when there are delays in routing the addresses in the second message
3036 that are so long that the server times out. This is alleviated by not
3037 routing addresses that previously had routing defers when handling an
3038 existing connection, but even so, this case may occur (e.g. if a
3039 previously happily routed address starts giving routing defers). If the
3040 host is genuinely down, another non-continued message delivery will
3041 notice it soon enough. */
3043 if (delete_flag != 0 || !continuing)
3044 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
3046 /* We may have tried an expired host, if its retry time has come; ensure
3047 the status reflects the expiry for the benefit of any other addresses. */
3051 host->status = (host_is_expired)?
3052 hstatus_unusable_expired : hstatus_unusable;
3053 host->why = hwhy_deferred;
3057 /* If message_defer is set (host was OK, but every recipient got deferred
3058 because of some message-specific problem), or if that had happened
3059 previously so that a message retry key exists, add an appropriate item
3060 to the retry chain. Note that if there was a message defer but now there is
3061 a host defer, the message defer record gets deleted. That seems perfectly
3062 reasonable. Also, stop the message from being remembered as waiting
3063 for specific hosts. */
3065 if (message_defer || retry_message_key != NULL)
3067 int delete_flag = message_defer? 0 : rf_delete;
3068 if (retry_message_key == NULL)
3070 retry_message_key = ob->retry_include_ip_address?
3071 string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
3073 string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
3075 retry_add_item(addrlist, retry_message_key,
3076 rf_message | rf_host | delete_flag);
3077 update_waiting = FALSE;
3080 /* Any return other than DEFER (that is, OK or ERROR) means that the
3081 addresses have got their final statuses filled in for this host. In the OK
3082 case, see if any of them are deferred. */
3086 for (addr = addrlist; addr != NULL; addr = addr->next)
3088 if (addr->transport_return == DEFER)
3090 some_deferred = TRUE;
3096 /* If no addresses deferred or the result was ERROR, return. We do this for
3097 ERROR because a failing filter set-up or add_headers expansion is likely to
3098 fail for any host we try. */
3100 if (rc == ERROR || (rc == OK && !some_deferred))
3102 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3103 return TRUE; /* Each address has its status */
3106 /* If the result was DEFER or some individual addresses deferred, let
3107 the loop run to try other hosts with the deferred addresses, except for the
3108 case when we were trying to deliver down an existing channel and failed.
3109 Don't try any other hosts in this case. */
3111 if (continuing) break;
3113 /* If the whole delivery, or some individual addresses, were deferred and
3114 there are more hosts that could be tried, do not count this host towards
3115 the hosts_max_try limit if the age of the message is greater than the
3116 maximum retry time for this host. This means we may try try all hosts,
3117 ignoring the limit, when messages have been around for some time. This is
3118 important because if we don't try all hosts, the address will never time
3119 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
3121 if ((rc == DEFER || some_deferred) && nexthost != NULL)
3124 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
3126 if (retry != NULL && retry->rules != NULL)
3128 retry_rule *last_rule;
3129 for (last_rule = retry->rules;
3130 last_rule->next != NULL;
3131 last_rule = last_rule->next);
3132 timedout = time(NULL) - received_time > last_rule->timeout;
3134 else timedout = TRUE; /* No rule => timed out */
3138 unexpired_hosts_tried--;
3139 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
3140 "hosts_max_try (message older than host's retry time)\n");
3143 } /* End of loop for trying multiple hosts. */
3145 /* This is the end of the loop that repeats iff expired is TRUE and
3146 ob->delay_after_cutoff is FALSE. The second time round we will
3147 try those hosts that haven't been tried since the message arrived. */
3151 debug_printf("all IP addresses skipped or deferred at least one address\n");
3152 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
3153 debug_printf("retrying IP addresses not tried since message arrived\n");
3158 /* Get here if all IP addresses are skipped or defer at least one address. In
3159 MUA wrapper mode, this will happen only for connection or other non-message-
3160 specific failures. Force the delivery status for all addresses to FAIL. */
3164 for (addr = addrlist; addr != NULL; addr = addr->next)
3165 addr->transport_return = FAIL;
3169 /* In the normal, non-wrapper case, add a standard message to each deferred
3170 address if there hasn't been an error, that is, if it hasn't actually been
3171 tried this time. The variable "expired" will be FALSE if any deliveries were
3172 actually tried, or if there was at least one host that was not expired. That
3173 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
3174 a delivery has been tried, an error code will be set, and the failing of the
3175 message is handled by the retry code later.
3177 If queue_smtp is set, or this transport was called to send a subsequent message
3178 down an existing TCP/IP connection, and something caused the host not to be
3179 found, we end up here, but can detect these cases and handle them specially. */
3181 for (addr = addrlist; addr != NULL; addr = addr->next)
3183 /* If host is not NULL, it means that we stopped processing the host list
3184 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
3185 means we need to behave as if some hosts were skipped because their retry
3186 time had not come. Specifically, this prevents the address from timing out.
3187 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
3188 hosts were tried. */
3192 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
3195 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
3196 "hosts were tried\n");
3201 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
3202 setflag(addr, af_retry_skipped);
3206 if (queue_smtp) /* no deliveries attempted */
3208 addr->transport_return = DEFER;
3209 addr->basic_errno = 0;
3210 addr->message = US"SMTP delivery explicitly queued";
3213 else if (addr->transport_return == DEFER &&
3214 (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0) &&
3215 addr->message == NULL)
3217 addr->basic_errno = ERRNO_HRETRY;
3218 if (continue_hostname != NULL)
3220 addr->message = US"no host found for existing SMTP connection";
3224 setflag(addr, af_pass_message); /* This is not a security risk */
3225 addr->message = (ob->delay_after_cutoff)?
3226 US"retry time not reached for any host after a long failure period" :
3227 US"all hosts have been failing for a long time and were last tried "
3228 "after this message arrived";
3230 /* If we are already using fallback hosts, or there are no fallback hosts
3231 defined, convert the result to FAIL to cause a bounce. */
3233 if (addr->host_list == addr->fallback_hosts ||
3234 addr->fallback_hosts == NULL)
3235 addr->transport_return = FAIL;
3239 if (hosts_retry == hosts_total)
3240 addr->message = US"retry time not reached for any host";
3241 else if (hosts_fail == hosts_total)
3242 addr->message = US"all host address lookups failed permanently";
3243 else if (hosts_defer == hosts_total)
3244 addr->message = US"all host address lookups failed temporarily";
3245 else if (hosts_serial == hosts_total)
3246 addr->message = US"connection limit reached for all hosts";
3247 else if (hosts_fail+hosts_defer == hosts_total)
3248 addr->message = US"all host address lookups failed";
3249 else addr->message = US"some host address lookups failed and retry time "
3250 "not reached for other hosts or connection limit reached";
3255 /* Update the database which keeps information about which messages are waiting
3256 for which hosts to become available. For some message-specific errors, the
3257 update_waiting flag is turned off because we don't want follow-on deliveries in
3258 those cases. If this transport instance is explicitly limited to one message
3259 per connection then follow-on deliveries are not possible and there's no need
3260 to create/update the per-transport wait-<transport_name> database. */
3262 if (update_waiting && tblock->connection_max_messages != 1)
3263 transport_update_waiting(hostlist, tblock->name);
3267 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3269 return TRUE; /* Each address has its status */
3272 /* End of transport/smtp.c */