1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2014 */
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 { "dnssec_request_domains", opt_stringptr,
59 (void *)offsetof(smtp_transport_options_block, dnssec_request_domains) },
60 { "dnssec_require_domains", opt_stringptr,
61 (void *)offsetof(smtp_transport_options_block, dnssec_require_domains) },
62 { "dscp", opt_stringptr,
63 (void *)offsetof(smtp_transport_options_block, dscp) },
64 { "fallback_hosts", opt_stringptr,
65 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
66 { "final_timeout", opt_time,
67 (void *)offsetof(smtp_transport_options_block, final_timeout) },
68 { "gethostbyname", opt_bool,
69 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
71 /* These are no longer honoured, as of Exim 4.80; for now, we silently
72 ignore; a later release will warn, and a later-still release will remove
73 these options, so that using them becomes an error. */
74 { "gnutls_require_kx", opt_stringptr,
75 (void *)offsetof(smtp_transport_options_block, gnutls_require_kx) },
76 { "gnutls_require_mac", opt_stringptr,
77 (void *)offsetof(smtp_transport_options_block, gnutls_require_mac) },
78 { "gnutls_require_protocols", opt_stringptr,
79 (void *)offsetof(smtp_transport_options_block, gnutls_require_proto) },
81 { "helo_data", opt_stringptr,
82 (void *)offsetof(smtp_transport_options_block, helo_data) },
83 { "hosts", opt_stringptr,
84 (void *)offsetof(smtp_transport_options_block, hosts) },
85 { "hosts_avoid_esmtp", opt_stringptr,
86 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
87 { "hosts_avoid_pipelining", opt_stringptr,
88 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
90 { "hosts_avoid_tls", opt_stringptr,
91 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
93 { "hosts_max_try", opt_int,
94 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
95 { "hosts_max_try_hardlimit", opt_int,
96 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
98 { "hosts_nopass_tls", opt_stringptr,
99 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
101 { "hosts_override", opt_bool,
102 (void *)offsetof(smtp_transport_options_block, hosts_override) },
103 { "hosts_randomize", opt_bool,
104 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
105 { "hosts_require_auth", opt_stringptr,
106 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
108 # if defined EXPERIMENTAL_OCSP
109 { "hosts_require_ocsp", opt_stringptr,
110 (void *)offsetof(smtp_transport_options_block, hosts_require_ocsp) },
112 { "hosts_require_tls", opt_stringptr,
113 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
115 { "hosts_try_auth", opt_stringptr,
116 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
117 #ifdef EXPERIMENTAL_PRDR
118 { "hosts_try_prdr", opt_stringptr,
119 (void *)offsetof(smtp_transport_options_block, hosts_try_prdr) },
122 { "hosts_verify_avoid_tls", opt_stringptr,
123 (void *)offsetof(smtp_transport_options_block, hosts_verify_avoid_tls) },
125 { "interface", opt_stringptr,
126 (void *)offsetof(smtp_transport_options_block, interface) },
127 { "keepalive", opt_bool,
128 (void *)offsetof(smtp_transport_options_block, keepalive) },
129 { "lmtp_ignore_quota", opt_bool,
130 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
131 { "max_rcpt", opt_int | opt_public,
132 (void *)offsetof(transport_instance, max_addresses) },
133 { "multi_domain", opt_bool | opt_public,
134 (void *)offsetof(transport_instance, multi_domain) },
135 { "port", opt_stringptr,
136 (void *)offsetof(smtp_transport_options_block, port) },
137 { "protocol", opt_stringptr,
138 (void *)offsetof(smtp_transport_options_block, protocol) },
139 { "retry_include_ip_address", opt_bool,
140 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
141 { "serialize_hosts", opt_stringptr,
142 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
143 { "size_addition", opt_int,
144 (void *)offsetof(smtp_transport_options_block, size_addition) }
146 ,{ "tls_certificate", opt_stringptr,
147 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
148 { "tls_crl", opt_stringptr,
149 (void *)offsetof(smtp_transport_options_block, tls_crl) },
150 { "tls_dh_min_bits", opt_int,
151 (void *)offsetof(smtp_transport_options_block, tls_dh_min_bits) },
152 { "tls_privatekey", opt_stringptr,
153 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
154 { "tls_require_ciphers", opt_stringptr,
155 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
156 { "tls_sni", opt_stringptr,
157 (void *)offsetof(smtp_transport_options_block, tls_sni) },
158 { "tls_tempfail_tryclear", opt_bool,
159 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
160 { "tls_try_verify_hosts", opt_stringptr,
161 (void *)offsetof(smtp_transport_options_block, tls_try_verify_hosts) },
162 { "tls_verify_certificates", opt_stringptr,
163 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) },
164 { "tls_verify_hosts", opt_stringptr,
165 (void *)offsetof(smtp_transport_options_block, tls_verify_hosts) }
167 #ifdef EXPERIMENTAL_TPDA
168 ,{ "tpda_host_defer_action", opt_stringptr,
169 (void *)offsetof(smtp_transport_options_block, tpda_host_defer_action) },
173 /* Size of the options list. An extern variable has to be used so that its
174 address can appear in the tables drtables.c. */
176 int smtp_transport_options_count =
177 sizeof(smtp_transport_options)/sizeof(optionlist);
179 /* Default private options block for the smtp transport. */
181 smtp_transport_options_block smtp_transport_option_defaults = {
183 NULL, /* fallback_hosts */
185 NULL, /* fallback_hostlist */
186 NULL, /* authenticated_sender */
187 US"$primary_hostname", /* helo_data */
188 NULL, /* interface */
190 US"smtp", /* protocol */
192 NULL, /* serialize_hosts */
193 NULL, /* hosts_try_auth */
194 NULL, /* hosts_require_auth */
195 #ifdef EXPERIMENTAL_PRDR
196 NULL, /* hosts_try_prdr */
198 #ifdef EXPERIMENTAL_OCSP
199 NULL, /* hosts_require_ocsp */
201 NULL, /* hosts_require_tls */
202 NULL, /* hosts_avoid_tls */
203 US"*", /* hosts_verify_avoid_tls */
204 NULL, /* hosts_avoid_pipelining */
205 NULL, /* hosts_avoid_esmtp */
206 NULL, /* hosts_nopass_tls */
207 5*60, /* command_timeout */
208 5*60, /* connect_timeout; shorter system default overrides */
209 5*60, /* data timeout */
210 10*60, /* final timeout */
211 1024, /* size_addition */
212 5, /* hosts_max_try */
213 50, /* hosts_max_try_hardlimit */
214 TRUE, /* address_retry_include_sender */
215 FALSE, /* allow_localhost */
216 FALSE, /* authenticated_sender_force */
217 FALSE, /* gethostbyname */
218 TRUE, /* dns_qualify_single */
219 FALSE, /* dns_search_parents */
220 NULL, /* dnssec_request_domains */
221 NULL, /* dnssec_require_domains */
222 TRUE, /* delay_after_cutoff */
223 FALSE, /* hosts_override */
224 FALSE, /* hosts_randomize */
225 TRUE, /* keepalive */
226 FALSE, /* lmtp_ignore_quota */
227 TRUE /* retry_include_ip_address */
229 ,NULL, /* tls_certificate */
231 NULL, /* tls_privatekey */
232 NULL, /* tls_require_ciphers */
233 NULL, /* gnutls_require_kx */
234 NULL, /* gnutls_require_mac */
235 NULL, /* gnutls_require_proto */
237 NULL, /* tls_verify_certificates */
238 EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
239 /* tls_dh_min_bits */
240 TRUE, /* tls_tempfail_tryclear */
241 NULL, /* tls_verify_hosts */
242 NULL /* tls_try_verify_hosts */
245 ,NULL, /* dkim_canon */
246 NULL, /* dkim_domain */
247 NULL, /* dkim_private_key */
248 NULL, /* dkim_selector */
249 NULL, /* dkim_sign_headers */
250 NULL /* dkim_strict */
252 #ifdef EXPERIMENTAL_TPDA
253 ,NULL /* tpda_host_defer_action */
260 static uschar *smtp_command; /* Points to last cmd for error messages */
261 static uschar *mail_command; /* Points to MAIL cmd for error messages */
262 static BOOL update_waiting; /* TRUE to update the "wait" database */
265 /*************************************************
266 * Setup entry point *
267 *************************************************/
269 /* This function is called when the transport is about to be used,
270 but before running it in a sub-process. It is used for two things:
272 (1) To set the fallback host list in addresses, when delivering.
273 (2) To pass back the interface, port, protocol, and other options, for use
274 during callout verification.
277 tblock pointer to the transport instance block
278 addrlist list of addresses about to be transported
279 tf if not NULL, pointer to block in which to return options
280 uid the uid that will be set (not used)
281 gid the gid that will be set (not used)
282 errmsg place for error message (not used)
284 Returns: OK always (FAIL, DEFER not used)
288 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
289 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
291 smtp_transport_options_block *ob =
292 (smtp_transport_options_block *)(tblock->options_block);
294 errmsg = errmsg; /* Keep picky compilers happy */
298 /* Pass back options if required. This interface is getting very messy. */
302 tf->interface = ob->interface;
304 tf->protocol = ob->protocol;
305 tf->hosts = ob->hosts;
306 tf->hosts_override = ob->hosts_override;
307 tf->hosts_randomize = ob->hosts_randomize;
308 tf->gethostbyname = ob->gethostbyname;
309 tf->qualify_single = ob->dns_qualify_single;
310 tf->search_parents = ob->dns_search_parents;
311 tf->helo_data = ob->helo_data;
314 /* Set the fallback host list for all the addresses that don't have fallback
315 host lists, provided that the local host wasn't present in the original host
318 if (!testflag(addrlist, af_local_host_removed))
320 for (; addrlist != NULL; addrlist = addrlist->next)
321 if (addrlist->fallback_hosts == NULL)
322 addrlist->fallback_hosts = ob->fallback_hostlist;
330 /*************************************************
331 * Initialization entry point *
332 *************************************************/
334 /* Called for each instance, after its options have been read, to
335 enable consistency checks to be done, or anything else that needs
338 Argument: pointer to the transport instance block
343 smtp_transport_init(transport_instance *tblock)
345 smtp_transport_options_block *ob =
346 (smtp_transport_options_block *)(tblock->options_block);
348 /* Retry_use_local_part defaults FALSE if unset */
350 if (tblock->retry_use_local_part == TRUE_UNSET)
351 tblock->retry_use_local_part = FALSE;
353 /* Set the default port according to the protocol */
355 if (ob->port == NULL)
356 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
357 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
359 /* Set up the setup entry point, to be called before subprocesses for this
362 tblock->setup = smtp_transport_setup;
364 /* Complain if any of the timeouts are zero. */
366 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
367 ob->final_timeout <= 0)
368 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
369 "command, data, or final timeout value is zero for %s transport",
372 /* If hosts_override is set and there are local hosts, set the global
373 flag that stops verify from showing router hosts. */
375 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
377 /* If there are any fallback hosts listed, build a chain of host items
378 for them, but do not do any lookups at this time. */
380 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
387 /*************************************************
388 * Set delivery info into all active addresses *
389 *************************************************/
391 /* Only addresses whose status is >= PENDING are relevant. A lesser
392 status means that an address is not currently being processed.
395 addrlist points to a chain of addresses
396 errno_value to put in each address's errno field
397 msg to put in each address's message field
398 rc to put in each address's transport_return field
399 pass_message if TRUE, set the "pass message" flag in the address
401 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
402 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
403 this particular type of timeout.
409 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
414 if (errno_value == ERRNO_CONNECTTIMEOUT)
416 errno_value = ETIMEDOUT;
417 orvalue = RTEF_CTOUT;
419 for (addr = addrlist; addr != NULL; addr = addr->next)
421 if (addr->transport_return < PENDING) continue;
422 addr->basic_errno = errno_value;
423 addr->more_errno |= orvalue;
427 if (pass_message) setflag(addr, af_pass_message);
429 addr->transport_return = rc;
435 /*************************************************
436 * Check an SMTP response *
437 *************************************************/
439 /* This function is given an errno code and the SMTP response buffer
440 to analyse, together with the host identification for generating messages. It
441 sets an appropriate message and puts the first digit of the response code into
442 the yield variable. If no response was actually read, a suitable digit is
446 host the current host, to get its name for messages
447 errno_value pointer to the errno value
448 more_errno from the top address for use with ERRNO_FILTER_FAIL
449 buffer the SMTP response buffer
450 yield where to put a one-digit SMTP response code
451 message where to put an errror message
452 pass_message set TRUE if message is an SMTP response
454 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
457 static BOOL check_response(host_item *host, int *errno_value, int more_errno,
458 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
462 if (smtp_use_pipelining &&
463 (Ustrcmp(smtp_command, "MAIL") == 0 ||
464 Ustrcmp(smtp_command, "RCPT") == 0 ||
465 Ustrcmp(smtp_command, "DATA") == 0))
468 *yield = '4'; /* Default setting is to give a temporary error */
470 /* Handle response timeout */
472 if (*errno_value == ETIMEDOUT)
474 *message = US string_sprintf("SMTP timeout while connected to %s [%s] "
475 "after %s%s", host->name, host->address, pl, smtp_command);
476 if (transport_count > 0)
477 *message = US string_sprintf("%s (%d bytes written)", *message,
482 /* Handle malformed SMTP response */
484 if (*errno_value == ERRNO_SMTPFORMAT)
486 uschar *malfresp = string_printing(buffer);
487 while (isspace(*malfresp)) malfresp++;
489 *message = string_sprintf("Malformed SMTP reply (an empty line) from "
490 "%s [%s] in response to %s%s", host->name, host->address, pl,
493 *message = string_sprintf("Malformed SMTP reply from %s [%s] in response "
494 "to %s%s: %s", host->name, host->address, pl, smtp_command, malfresp);
498 /* Handle a failed filter process error; can't send QUIT as we mustn't
501 if (*errno_value == ERRNO_FILTER_FAIL)
503 *message = US string_sprintf("transport filter process failed (%d)%s",
505 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
509 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
512 if (*errno_value == ERRNO_CHHEADER_FAIL)
515 US string_sprintf("failed to expand headers_add or headers_remove: %s",
516 expand_string_message);
520 /* Handle failure to write a complete data block */
522 if (*errno_value == ERRNO_WRITEINCOMPLETE)
524 *message = US string_sprintf("failed to write a data block");
528 /* Handle error responses from the remote mailer. */
532 uschar *s = string_printing(buffer);
533 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
534 "host %s [%s]: %s", pl, smtp_command, host->name, host->address, s);
535 *pass_message = TRUE;
540 /* No data was read. If there is no errno, this must be the EOF (i.e.
541 connection closed) case, which causes deferral. An explicit connection reset
542 error has the same effect. Otherwise, put the host's identity in the message,
543 leaving the errno value to be interpreted as well. In all cases, we have to
544 assume the connection is now dead. */
546 if (*errno_value == 0 || *errno_value == ECONNRESET)
548 *errno_value = ERRNO_SMTPCLOSED;
549 *message = US string_sprintf("Remote host %s [%s] closed connection "
550 "in response to %s%s", host->name, host->address, pl, smtp_command);
552 else *message = US string_sprintf("%s [%s]", host->name, host->address);
559 /*************************************************
560 * Write error message to logs *
561 *************************************************/
563 /* This writes to the main log and to the message log.
566 addr the address item containing error information
567 host the current host
573 write_logs(address_item *addr, host_item *host)
575 if (addr->message != NULL)
577 uschar *message = addr->message;
578 if (addr->basic_errno > 0)
579 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
580 log_write(0, LOG_MAIN, "%s", message);
581 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
586 ((log_extra_selector & LX_outgoing_port) != 0)?
587 string_sprintf("%s [%s]:%d", host->name, host->address,
588 (host->port == PORT_NONE)? 25 : host->port)
590 string_sprintf("%s [%s]", host->name, host->address);
591 log_write(0, LOG_MAIN, "%s %s", msg, strerror(addr->basic_errno));
592 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), msg,
593 strerror(addr->basic_errno));
599 #ifdef EXPERIMENTAL_TPDA
600 /*************************************************
601 * Post-defer action *
602 *************************************************/
604 /* This expands an arbitrary per-transport string.
605 It might, for example, be used to write to the database log.
608 ob transport options block
609 addr the address item containing error information
610 host the current host
616 tpda_deferred(smtp_transport_options_block *ob, address_item *addr, host_item *host)
618 uschar *action = ob->tpda_host_defer_action;
622 tpda_delivery_ip = string_copy(host->address);
623 tpda_delivery_port = (host->port == PORT_NONE)? 25 : host->port;
624 tpda_delivery_fqdn = string_copy(host->name);
625 tpda_delivery_local_part = string_copy(addr->local_part);
626 tpda_delivery_domain = string_copy(addr->domain);
627 tpda_defer_errno = addr->basic_errno;
629 tpda_defer_errstr = addr->message
630 ? addr->basic_errno > 0
631 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
632 : string_copy(addr->message)
633 : addr->basic_errno > 0
634 ? string_copy(strerror(addr->basic_errno))
638 debug_printf(" TPDA(host defer): tpda_host_defer_action=|%s| tpda_delivery_IP=%s\n",
639 action, tpda_delivery_ip);
641 router_name = addr->router->name;
642 transport_name = addr->transport->name;
643 if (!expand_string(action) && *expand_string_message)
644 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand tpda_defer_action in %s: %s\n",
645 transport_name, expand_string_message);
646 router_name = transport_name = NULL;
652 /*************************************************
653 * Synchronize SMTP responses *
654 *************************************************/
656 /* This function is called from smtp_deliver() to receive SMTP responses from
657 the server, and match them up with the commands to which they relate. When
658 PIPELINING is not in use, this function is called after every command, and is
659 therefore somewhat over-engineered, but it is simpler to use a single scheme
660 that works both with and without PIPELINING instead of having two separate sets
663 The set of commands that are buffered up with pipelining may start with MAIL
664 and may end with DATA; in between are RCPT commands that correspond to the
665 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
666 etc.) are never buffered.
668 Errors after MAIL or DATA abort the whole process leaving the response in the
669 buffer. After MAIL, pending responses are flushed, and the original command is
670 re-instated in big_buffer for error messages. For RCPT commands, the remote is
671 permitted to reject some recipient addresses while accepting others. However
672 certain errors clearly abort the whole process. Set the value in
673 transport_return to PENDING_OK if the address is accepted. If there is a
674 subsequent general error, it will get reset accordingly. If not, it will get
675 converted to OK at the end.
678 addrlist the complete address list
679 include_affixes TRUE if affixes include in RCPT
680 sync_addr ptr to the ptr of the one to start scanning at (updated)
681 host the host we are connected to
682 count the number of responses to read
684 include_sender true if 4xx retry is to include the sender it its key
685 pending_MAIL true if the first response is for MAIL
686 pending_DATA 0 if last command sent was not DATA
687 +1 if previously had a good recipient
688 -1 if not previously had a good recipient
689 inblock incoming SMTP block
690 timeout timeout value
691 buffer buffer for reading response
692 buffsize size of buffer
694 Returns: 3 if at least one address had 2xx and one had 5xx
695 2 if at least one address had 5xx but none had 2xx
696 1 if at least one host had a 2xx response, but none had 5xx
697 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
698 -1 timeout while reading RCPT response
699 -2 I/O or other non-response error for RCPT
700 -3 DATA or MAIL failed - errno and buffer set
704 sync_responses(address_item *addrlist, BOOL include_affixes,
705 address_item **sync_addr, host_item *host, int count,
706 BOOL address_retry_include_sender, BOOL pending_MAIL,
707 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
710 address_item *addr = *sync_addr;
713 /* Handle the response for a MAIL command. On error, reinstate the original
714 command in big_buffer for error message use, and flush any further pending
715 responses before returning, except after I/O errors and timeouts. */
720 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
722 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
723 if (errno == 0 && buffer[0] != 0)
725 uschar flushbuffer[4096];
727 if (buffer[0] == '4')
729 save_errno = ERRNO_MAIL4XX;
730 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
734 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
736 && (errno != 0 || flushbuffer[0] == 0))
745 if (pending_DATA) count--; /* Number of RCPT responses to come */
747 /* Read and handle the required number of RCPT responses, matching each one up
748 with an address by scanning for the next address whose status is PENDING_DEFER.
753 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
755 /* The address was accepted */
757 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
760 addr->transport_return = PENDING_OK;
762 /* If af_dr_retry_exists is set, there was a routing delay on this address;
763 ensure that any address-specific retry record is expunged. We do this both
764 for the basic key and for the version that also includes the sender. */
766 if (testflag(addr, af_dr_retry_exists))
768 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
770 retry_add_item(addr, altkey, rf_delete);
771 retry_add_item(addr, addr->address_retry_key, rf_delete);
775 /* Timeout while reading the response */
777 else if (errno == ETIMEDOUT)
779 int save_errno = errno;
780 uschar *message = string_sprintf("SMTP timeout while connected to %s [%s] "
781 "after RCPT TO:<%s>", host->name, host->address,
782 transport_rcpt_address(addr, include_affixes));
783 set_errno(addrlist, save_errno, message, DEFER, FALSE);
784 retry_add_item(addr, addr->address_retry_key, 0);
785 update_waiting = FALSE;
789 /* Handle other errors in obtaining an SMTP response by returning -1. This
790 will cause all the addresses to be deferred. Restore the SMTP command in
791 big_buffer for which we are checking the response, so the error message
794 else if (errno != 0 || buffer[0] == 0)
796 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
797 transport_rcpt_address(addr, include_affixes));
801 /* Handle SMTP permanent and temporary response codes. */
806 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
807 "host %s [%s]: %s", transport_rcpt_address(addr, include_affixes),
808 host->name, host->address, string_printing(buffer));
809 setflag(addr, af_pass_message);
810 deliver_msglog("%s %s\n", tod_stamp(tod_log), addr->message);
812 /* The response was 5xx */
814 if (buffer[0] == '5')
816 addr->transport_return = FAIL;
820 /* The response was 4xx */
824 addr->transport_return = DEFER;
825 addr->basic_errno = ERRNO_RCPT4XX;
826 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
828 /* Log temporary errors if there are more hosts to be tried. */
830 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", addr->message);
832 /* Do not put this message on the list of those waiting for specific
833 hosts, as otherwise it is likely to be tried too often. */
835 update_waiting = FALSE;
837 /* Add a retry item for the address so that it doesn't get tried again
838 too soon. If address_retry_include_sender is true, add the sender address
841 if (address_retry_include_sender)
843 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
845 retry_add_item(addr, altkey, 0);
847 else retry_add_item(addr, addr->address_retry_key, 0);
850 } /* Loop for next RCPT response */
852 /* Update where to start at for the next block of responses, unless we
853 have already handled all the addresses. */
855 if (addr != NULL) *sync_addr = addr->next;
857 /* Handle a response to DATA. If we have not had any good recipients, either
858 previously or in this block, the response is ignored. */
860 if (pending_DATA != 0 &&
861 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
866 if (pending_DATA > 0 || (yield & 1) != 0)
868 if (errno == 0 && buffer[0] == '4')
870 errno = ERRNO_DATA4XX;
871 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
875 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
876 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
877 "is in use and there were no good recipients\n", msg);
880 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
881 present) received 3xx. If any RCPTs were handled and yielded anything other
882 than 4xx, yield will be set non-zero. */
889 /* Do the client side of smtp-level authentication */
892 buffer EHLO response from server (gets overwritten)
893 addrlist chain of potential addresses to deliver
894 host host to deliver to
896 ibp, obp comms channel control blocks
899 OK Success, or failed (but not required): global "smtp_authenticated" set
900 DEFER Failed authentication (and was required)
901 ERROR Internal problem
903 FAIL_SEND Failed communications - transmit
908 smtp_auth(uschar *buffer, unsigned bufsize, address_item *addrlist, host_item *host,
909 smtp_transport_options_block *ob, BOOL is_esmtp,
910 smtp_inblock *ibp, smtp_outblock *obp)
913 uschar *fail_reason = US"server did not advertise AUTH support";
915 smtp_authenticated = FALSE;
916 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
917 require_auth = verify_check_this_host(&(ob->hosts_require_auth), NULL,
918 host->name, host->address, NULL);
920 if (is_esmtp && !regex_AUTH) regex_AUTH =
921 regex_must_compile(US"\\n250[\\s\\-]AUTH\\s+([\\-\\w\\s]+)(?:\\n|$)",
924 if (is_esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
926 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
927 expand_nmax = -1; /* reset */
929 /* Must not do this check until after we have saved the result of the
930 regex match above. */
932 if (require_auth == OK ||
933 verify_check_this_host(&(ob->hosts_try_auth), NULL, host->name,
934 host->address, NULL) == OK)
937 fail_reason = US"no common mechanisms were found";
939 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
941 /* Scan the configured authenticators looking for one which is configured
942 for use as a client, which is not suppressed by client_condition, and
943 whose name matches an authentication mechanism supported by the server.
944 If one is found, attempt to authenticate by calling its client function.
947 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
951 (au->client_condition != NULL &&
952 !expand_check_condition(au->client_condition, au->name,
953 US"client authenticator")))
955 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
957 (au->client)? "client_condition is false" :
958 "not configured as a client");
962 /* Loop to scan supported server mechanisms */
967 int len = Ustrlen(au->public_name);
968 while (isspace(*p)) p++;
970 if (strncmpic(au->public_name, p, len) != 0 ||
971 (p[len] != 0 && !isspace(p[len])))
973 while (*p != 0 && !isspace(*p)) p++;
977 /* Found data for a listed mechanism. Call its client entry. Set
978 a flag in the outblock so that data is overwritten after sending so
979 that reflections don't show it. */
981 fail_reason = US"authentication attempt(s) failed";
982 obp->authenticating = TRUE;
983 rc = (au->info->clientcode)(au, ibp, obp,
984 ob->command_timeout, buffer, bufsize);
985 obp->authenticating = FALSE;
986 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
989 /* A temporary authentication failure must hold up delivery to
990 this host. After a permanent authentication failure, we carry on
991 to try other authentication methods. If all fail hard, try to
992 deliver the message unauthenticated unless require_auth was set. */
997 smtp_authenticated = TRUE; /* stops the outer loop */
998 client_authenticator = au->name;
999 if (au->set_client_id != NULL)
1000 client_authenticated_id = expand_string(au->set_client_id);
1003 /* Failure after writing a command */
1008 /* Failure after reading a response */
1011 if (errno != 0 || buffer[0] != '5') return FAIL;
1012 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1013 au->name, host->name, host->address, buffer);
1016 /* Failure by some other means. In effect, the authenticator
1017 decided it wasn't prepared to handle this case. Typically this
1018 is the result of "fail" in an expansion string. Do we need to
1019 log anything here? Feb 2006: a message is now put in the buffer
1020 if logging is required. */
1024 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1025 "authentication H=%s [%s] %s", au->name, host->name,
1026 host->address, buffer);
1029 /* Internal problem, message in buffer. */
1032 set_errno(addrlist, 0, string_copy(buffer), DEFER, FALSE);
1036 break; /* If not authenticated, try next authenticator */
1037 } /* Loop for scanning supported server mechanisms */
1038 } /* Loop for further authenticators */
1042 /* If we haven't authenticated, but are required to, give up. */
1044 if (require_auth == OK && !smtp_authenticated)
1046 set_errno(addrlist, ERRNO_AUTHFAIL,
1047 string_sprintf("authentication required but %s", fail_reason), DEFER,
1056 /* Construct AUTH appendix string for MAIL TO */
1059 buffer to build string
1060 addrlist chain of potential addresses to deliver
1061 ob transport options
1063 Globals smtp_authenticated
1064 client_authenticated_sender
1065 Return True on error, otherwise buffer has (possibly empty) terminated string
1069 smtp_mail_auth_str(uschar *buffer, unsigned bufsize, address_item *addrlist,
1070 smtp_transport_options_block *ob)
1072 uschar *local_authenticated_sender = authenticated_sender;
1075 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n", authenticated_sender, ob->authenticated_sender, smtp_authenticated?"Y":"N");
1078 if (ob->authenticated_sender != NULL)
1080 uschar *new = expand_string(ob->authenticated_sender);
1083 if (!expand_string_forcedfail)
1085 uschar *message = string_sprintf("failed to expand "
1086 "authenticated_sender: %s", expand_string_message);
1087 set_errno(addrlist, 0, message, DEFER, FALSE);
1091 else if (new[0] != 0) local_authenticated_sender = new;
1094 /* Add the authenticated sender address if present */
1096 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1097 local_authenticated_sender != NULL)
1099 string_format(buffer, bufsize, " AUTH=%s",
1100 auth_xtextencode(local_authenticated_sender,
1101 Ustrlen(local_authenticated_sender)));
1102 client_authenticated_sender = string_copy(local_authenticated_sender);
1112 /*************************************************
1113 * Deliver address list to given host *
1114 *************************************************/
1116 /* If continue_hostname is not null, we get here only when continuing to
1117 deliver down an existing channel. The channel was passed as the standard
1118 input. TLS is never active on a passed channel; the previous process always
1119 closes it down before passing the connection on.
1121 Otherwise, we have to make a connection to the remote host, and do the
1122 initial protocol exchange.
1124 When running as an MUA wrapper, if the sender or any recipient is rejected,
1125 temporarily or permanently, we force failure for all recipients.
1128 addrlist chain of potential addresses to deliver; only those whose
1129 transport_return field is set to PENDING_DEFER are currently
1130 being processed; others should be skipped - they have either
1131 been delivered to an earlier host or IP address, or been
1132 failed by one of them.
1133 host host to deliver to
1134 host_af AF_INET or AF_INET6
1135 port default TCP/IP port to use, in host byte order
1136 interface interface to bind to, or NULL
1137 tblock transport instance block
1138 copy_host TRUE if host set in addr->host_used must be copied, because
1139 it is specific to this call of the transport
1140 message_defer set TRUE if yield is OK, but all addresses were deferred
1141 because of a non-recipient, non-host failure, that is, a
1142 4xx response to MAIL FROM, DATA, or ".". This is a defer
1143 that is specific to the message.
1144 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1145 a second attempt after TLS initialization fails
1147 Returns: OK - the connection was made and the delivery attempted;
1148 the result for each address is in its data block.
1149 DEFER - the connection could not be made, or something failed
1150 while setting up the SMTP session, or there was a
1151 non-message-specific error, such as a timeout.
1152 ERROR - a filter command is specified for this transport,
1153 and there was a problem setting it up; OR helo_data
1154 or add_headers or authenticated_sender is specified
1155 for this transport, and the string failed to expand
1159 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
1160 uschar *interface, transport_instance *tblock, BOOL copy_host,
1161 BOOL *message_defer, BOOL suppress_tls)
1164 address_item *sync_addr;
1165 address_item *first_addr = addrlist;
1170 time_t start_delivery_time = time(NULL);
1171 smtp_transport_options_block *ob =
1172 (smtp_transport_options_block *)(tblock->options_block);
1173 BOOL lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
1174 BOOL smtps = strcmpic(ob->protocol, US"smtps") == 0;
1176 BOOL send_rset = TRUE;
1177 BOOL send_quit = TRUE;
1178 BOOL setting_up = TRUE;
1179 BOOL completed_address = FALSE;
1182 BOOL pass_message = FALSE;
1183 #ifdef EXPERIMENTAL_PRDR
1184 BOOL prdr_offered = FALSE;
1187 smtp_inblock inblock;
1188 smtp_outblock outblock;
1189 int max_rcpt = tblock->max_addresses;
1190 uschar *igquotstr = US"";
1191 uschar *helo_data = NULL;
1192 uschar *message = NULL;
1193 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
1195 uschar buffer[4096];
1196 uschar inbuffer[4096];
1197 uschar outbuffer[1024];
1199 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
1201 *message_defer = FALSE;
1202 smtp_command = US"initial connection";
1203 if (max_rcpt == 0) max_rcpt = 999999;
1205 /* Set up the buffer for reading SMTP response packets. */
1207 inblock.buffer = inbuffer;
1208 inblock.buffersize = sizeof(inbuffer);
1209 inblock.ptr = inbuffer;
1210 inblock.ptrend = inbuffer;
1212 /* Set up the buffer for holding SMTP commands while pipelining */
1214 outblock.buffer = outbuffer;
1215 outblock.buffersize = sizeof(outbuffer);
1216 outblock.ptr = outbuffer;
1217 outblock.cmd_count = 0;
1218 outblock.authenticating = FALSE;
1220 /* Reset the parameters of a TLS session. */
1223 tls_out.cipher = NULL; /* the one we may use for this transport */
1224 tls_out.ourcert = NULL;
1225 tls_out.peercert = NULL;
1226 tls_out.peerdn = NULL;
1227 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1231 /* Flip the legacy TLS-related variables over to the outbound set in case
1232 they're used in the context of the transport. Don't bother resetting
1233 afterward as we're in a subprocess. */
1235 tls_modify_variables(&tls_out);
1240 set_errno(addrlist, 0, US"TLS support not available", DEFER, FALSE);
1245 /* Make a connection to the host if this isn't a continued delivery, and handle
1246 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
1247 specially so they can be identified for retries. */
1249 if (continue_hostname == NULL)
1251 inblock.sock = outblock.sock =
1252 smtp_connect(host, host_af, port, interface, ob->connect_timeout,
1253 ob->keepalive, ob->dscp); /* This puts port into host->port */
1255 if (inblock.sock < 0)
1257 set_errno(addrlist, (errno == ETIMEDOUT)? ERRNO_CONNECTTIMEOUT : errno,
1258 NULL, DEFER, FALSE);
1262 /* Expand the greeting message while waiting for the initial response. (Makes
1263 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1264 delayed till here so that $sending_interface and $sending_port are set. */
1266 helo_data = expand_string(ob->helo_data);
1268 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1269 is nevertheless a reasonably clean way of programming this kind of logic,
1270 where you want to escape on any error. */
1274 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1275 ob->command_timeout)) goto RESPONSE_FAILED;
1277 /* Now check if the helo_data expansion went well, and sign off cleanly if
1280 if (helo_data == NULL)
1282 uschar *message = string_sprintf("failed to expand helo_data: %s",
1283 expand_string_message);
1284 set_errno(addrlist, 0, message, DEFER, FALSE);
1290 /** Debugging without sending a message
1291 addrlist->transport_return = DEFER;
1295 /* Errors that occur after this point follow an SMTP command, which is
1296 left in big_buffer by smtp_write_command() for use in error messages. */
1298 smtp_command = big_buffer;
1300 /* Tell the remote who we are...
1302 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1303 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1304 greeting is of this form. The assumption was that the far end supports it
1305 properly... but experience shows that there are some that give 5xx responses,
1306 even though the banner includes "ESMTP" (there's a bloody-minded one that
1307 says "ESMTP not spoken here"). Cope with that case.
1309 September 2000: Time has passed, and it seems reasonable now to always send
1310 EHLO at the start. It is also convenient to make the change while installing
1313 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1314 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1315 would be no way to send out the mails, so there is now a host list
1316 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1317 PIPELINING problem as well. Maybe it can also be useful to cure other
1318 problems with broken servers.
1320 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1321 Then somebody tried it with a Microsoft mailer... It seems that all other
1322 mailers use upper case for some reason (the RFC is quite clear about case
1323 independence) so, for peace of mind, I gave in. */
1325 esmtp = verify_check_this_host(&(ob->hosts_avoid_esmtp), NULL,
1326 host->name, host->address, NULL) != OK;
1328 /* Alas; be careful, since this goto is not an error-out, so conceivably
1329 we might set data between here and the target which we assume to exist
1330 and be usable. I can see this coming back to bite us. */
1335 suppress_tls = FALSE;
1336 ob->tls_tempfail_tryclear = FALSE;
1337 smtp_command = US"SSL-on-connect";
1344 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1345 lmtp? "LHLO" : "EHLO", helo_data) < 0)
1347 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1348 ob->command_timeout))
1350 if (errno != 0 || buffer[0] == 0 || lmtp) goto RESPONSE_FAILED;
1357 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1362 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1364 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1365 ob->command_timeout)) goto RESPONSE_FAILED;
1368 /* Set IGNOREQUOTA if the response to LHLO specifies support and the
1369 lmtp_ignore_quota option was set. */
1371 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1372 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1373 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1375 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1378 tls_offered = esmtp &&
1379 pcre_exec(regex_STARTTLS, NULL, CS buffer, Ustrlen(buffer), 0,
1380 PCRE_EOPT, NULL, 0) >= 0;
1383 #ifdef EXPERIMENTAL_PRDR
1384 prdr_offered = esmtp &&
1385 (pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(buffer), 0,
1386 PCRE_EOPT, NULL, 0) >= 0) &&
1387 (verify_check_this_host(&(ob->hosts_try_prdr), NULL, host->name,
1388 host->address, NULL) == OK);
1391 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1395 /* For continuing deliveries down the same channel, the socket is the standard
1396 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1397 below). Set up the pointer to where subsequent commands will be left, for
1398 error messages. Note that smtp_use_size and smtp_use_pipelining will have been
1399 set from the command line if they were set in the process that passed the
1404 inblock.sock = outblock.sock = fileno(stdin);
1405 smtp_command = big_buffer;
1406 host->port = port; /* Record the port that was used */
1409 /* If TLS is available on this connection, whether continued or not, attempt to
1410 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1411 send another EHLO - the server may give a different answer in secure mode. We
1412 use a separate buffer for reading the response to STARTTLS so that if it is
1413 negative, the original EHLO data is available for subsequent analysis, should
1414 the client not be required to use TLS. If the response is bad, copy the buffer
1415 for error analysis. */
1418 if (tls_offered && !suppress_tls &&
1419 verify_check_this_host(&(ob->hosts_avoid_tls), NULL, host->name,
1420 host->address, NULL) != OK)
1422 uschar buffer2[4096];
1423 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1426 /* If there is an I/O error, transmission of this message is deferred. If
1427 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1428 false, we also defer. However, if there is a temporary rejection of STARTTLS
1429 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1430 STARTTLS, we carry on. This means we will try to send the message in clear,
1431 unless the host is in hosts_require_tls (tested below). */
1433 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1434 ob->command_timeout))
1436 if (errno != 0 || buffer2[0] == 0 ||
1437 (buffer2[0] == '4' && !ob->tls_tempfail_tryclear))
1439 Ustrncpy(buffer, buffer2, sizeof(buffer));
1440 goto RESPONSE_FAILED;
1444 /* STARTTLS accepted: try to negotiate a TLS session. */
1449 int rc = tls_client_start(inblock.sock,
1452 ob->tls_certificate,
1455 ob->tls_verify_certificates,
1457 ob->tls_require_ciphers,
1458 #ifdef EXPERIMENTAL_OCSP
1459 ob->hosts_require_ocsp,
1461 ob->tls_dh_min_bits,
1462 ob->command_timeout,
1463 ob->tls_verify_hosts,
1464 ob->tls_try_verify_hosts);
1466 /* TLS negotiation failed; give an error. From outside, this function may
1467 be called again to try in clear on a new connection, if the options permit
1468 it for this host. */
1472 save_errno = ERRNO_TLSFAILURE;
1473 message = US"failure while setting up TLS session";
1478 /* TLS session is set up */
1480 for (addr = addrlist; addr != NULL; addr = addr->next)
1482 if (addr->transport_return == PENDING_DEFER)
1484 addr->cipher = tls_out.cipher;
1485 addr->ourcert = tls_out.ourcert;
1486 addr->peercert = tls_out.peercert;
1487 addr->peerdn = tls_out.peerdn;
1493 /* if smtps, we'll have smtp_command set to something else; always safe to
1495 smtp_command = big_buffer;
1497 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1498 helo_data is null, we are dealing with a connection that was passed from
1499 another process, and so we won't have expanded helo_data above. We have to
1500 expand it here. $sending_ip_address and $sending_port are set up right at the
1501 start of the Exim process (in exim.c). */
1503 if (tls_out.active >= 0)
1506 if (helo_data == NULL)
1508 helo_data = expand_string(ob->helo_data);
1509 if (helo_data == NULL)
1511 uschar *message = string_sprintf("failed to expand helo_data: %s",
1512 expand_string_message);
1513 set_errno(addrlist, 0, message, DEFER, FALSE);
1519 /* For SMTPS we need to wait for the initial OK response. */
1522 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1523 ob->command_timeout)) goto RESPONSE_FAILED;
1527 greeting_cmd = "EHLO";
1530 greeting_cmd = "HELO";
1532 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1535 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1536 lmtp? "LHLO" : greeting_cmd, helo_data) < 0)
1538 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1539 ob->command_timeout))
1540 goto RESPONSE_FAILED;
1543 /* If the host is required to use a secure channel, ensure that we
1546 else if (verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
1547 host->address, NULL) == OK)
1549 save_errno = ERRNO_TLSREQUIRED;
1550 message = string_sprintf("a TLS session is required for %s [%s], but %s",
1551 host->name, host->address,
1552 tls_offered? "an attempt to start TLS failed" :
1553 "the server did not offer TLS support");
1558 /* If TLS is active, we have just started it up and re-done the EHLO command,
1559 so its response needs to be analyzed. If TLS is not active and this is a
1560 continued session down a previously-used socket, we haven't just done EHLO, so
1563 if (continue_hostname == NULL
1565 || tls_out.active >= 0
1569 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
1570 lmtp_ignore_quota option was set. */
1572 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1573 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1574 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1576 /* If the response to EHLO specified support for the SIZE parameter, note
1577 this, provided size_addition is non-negative. */
1579 smtp_use_size = esmtp && ob->size_addition >= 0 &&
1580 pcre_exec(regex_SIZE, NULL, CS buffer, Ustrlen(CS buffer), 0,
1581 PCRE_EOPT, NULL, 0) >= 0;
1583 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
1584 the current host, esmtp will be false, so PIPELINING can never be used. If
1585 the current host matches hosts_avoid_pipelining, don't do it. */
1587 smtp_use_pipelining = esmtp &&
1588 verify_check_this_host(&(ob->hosts_avoid_pipelining), NULL, host->name,
1589 host->address, NULL) != OK &&
1590 pcre_exec(regex_PIPELINING, NULL, CS buffer, Ustrlen(CS buffer), 0,
1591 PCRE_EOPT, NULL, 0) >= 0;
1593 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
1594 smtp_use_pipelining? "" : "not ");
1596 #ifdef EXPERIMENTAL_PRDR
1597 prdr_offered = esmtp &&
1598 pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(CS buffer), 0,
1599 PCRE_EOPT, NULL, 0) >= 0 &&
1600 verify_check_this_host(&(ob->hosts_try_prdr), NULL, host->name,
1601 host->address, NULL) == OK;
1604 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1607 /* Note if the response to EHLO specifies support for the AUTH extension.
1608 If it has, check that this host is one we want to authenticate to, and do
1609 the business. The host name and address must be available when the
1610 authenticator's client driver is running. */
1612 switch (yield = smtp_auth(buffer, sizeof(buffer), addrlist, host,
1613 ob, esmtp, &inblock, &outblock))
1615 default: goto SEND_QUIT;
1617 case FAIL_SEND: goto SEND_FAILED;
1618 case FAIL: goto RESPONSE_FAILED;
1622 /* The setting up of the SMTP call is now complete. Any subsequent errors are
1623 message-specific. */
1627 /* If there is a filter command specified for this transport, we can now
1628 set it up. This cannot be done until the identify of the host is known. */
1630 if (tblock->filter_command != NULL)
1634 sprintf(CS buffer, "%.50s transport", tblock->name);
1635 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
1636 TRUE, DEFER, addrlist, buffer, NULL);
1637 transport_filter_timeout = tblock->filter_timeout;
1639 /* On failure, copy the error to all addresses, abandon the SMTP call, and
1644 set_errno(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
1652 /* For messages that have more than the maximum number of envelope recipients,
1653 we want to send several transactions down the same SMTP connection. (See
1654 comments in deliver.c as to how this reconciles, heuristically, with
1655 remote_max_parallel.) This optimization was added to Exim after the following
1656 code was already working. The simplest way to put it in without disturbing the
1657 code was to use a goto to jump back to this point when there is another
1658 transaction to handle. */
1661 sync_addr = first_addr;
1665 completed_address = FALSE;
1668 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
1669 qualification, send it, adding something to the message size to allow for
1670 imprecision and things that get added en route. Exim keeps the number of lines
1671 in a message, so we can give an accurate value for the original message, but we
1672 need some additional to handle added headers. (Double "." characters don't get
1673 included in the count.) */
1680 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
1684 #ifdef EXPERIMENTAL_PRDR
1685 prdr_active = FALSE;
1688 for (addr = first_addr; addr; addr = addr->next)
1689 if (addr->transport_return == PENDING_DEFER)
1691 for (addr = addr->next; addr; addr = addr->next)
1692 if (addr->transport_return == PENDING_DEFER)
1693 { /* at least two recipients to send */
1695 sprintf(CS p, " PRDR"); p += 5;
1696 goto prdr_is_active;
1704 /* If an authenticated_sender override has been specified for this transport
1705 instance, expand it. If the expansion is forced to fail, and there was already
1706 an authenticated_sender for this message, the original value will be used.
1707 Other expansion failures are serious. An empty result is ignored, but there is
1708 otherwise no check - this feature is expected to be used with LMTP and other
1709 cases where non-standard addresses (e.g. without domains) might be required. */
1711 if (smtp_mail_auth_str(p, sizeof(buffer) - (p-buffer), addrlist, ob))
1714 /* From here until we send the DATA command, we can make use of PIPELINING
1715 if the server host supports it. The code has to be able to check the responses
1716 at any point, for when the buffer fills up, so we write it totally generally.
1717 When PIPELINING is off, each command written reports that it has flushed the
1720 pending_MAIL = TRUE; /* The block starts with MAIL */
1722 rc = smtp_write_command(&outblock, smtp_use_pipelining,
1723 "MAIL FROM:<%s>%s\r\n", return_path, buffer);
1724 mail_command = string_copy(big_buffer); /* Save for later error message */
1728 case -1: /* Transmission error */
1731 case +1: /* Block was sent */
1732 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1733 ob->command_timeout))
1735 if (errno == 0 && buffer[0] == '4')
1737 errno = ERRNO_MAIL4XX;
1738 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1740 goto RESPONSE_FAILED;
1742 pending_MAIL = FALSE;
1746 /* Pass over all the relevant recipient addresses for this host, which are the
1747 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
1748 several before we have to read the responses for those seen so far. This
1749 checking is done by a subroutine because it also needs to be done at the end.
1750 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
1751 the next one if not all are sent.
1753 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
1754 last address because we want to abort if any recipients have any kind of
1755 problem, temporary or permanent. We know that all recipient addresses will have
1756 the PENDING_DEFER status, because only one attempt is ever made, and we know
1757 that max_rcpt will be large, so all addresses will be done at once. */
1759 for (addr = first_addr;
1760 address_count < max_rcpt && addr != NULL;
1766 if (addr->transport_return != PENDING_DEFER) continue;
1769 no_flush = smtp_use_pipelining && (!mua_wrapper || addr->next != NULL);
1771 /* Now send the RCPT command, and process outstanding responses when
1772 necessary. After a timeout on RCPT, we just end the function, leaving the
1773 yield as OK, because this error can often mean that there is a problem with
1774 just one address, so we don't want to delay the host. */
1776 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s\r\n",
1777 transport_rcpt_address(addr, tblock->rcpt_include_affixes), igquotstr);
1778 if (count < 0) goto SEND_FAILED;
1781 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
1782 &sync_addr, host, count, ob->address_retry_include_sender,
1783 pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
1786 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1787 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1790 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1791 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1792 case 0: /* No 2xx or 5xx, but no probs */
1795 case -1: goto END_OFF; /* Timeout on RCPT */
1796 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
1798 pending_MAIL = FALSE; /* Dealt with MAIL */
1800 } /* Loop for next address */
1802 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
1803 permanently or temporarily. We should have flushed and synced after the last
1808 address_item *badaddr;
1809 for (badaddr = first_addr; badaddr != NULL; badaddr = badaddr->next)
1811 if (badaddr->transport_return != PENDING_OK) break;
1813 if (badaddr != NULL)
1815 set_errno(addrlist, 0, badaddr->message, FAIL,
1816 testflag(badaddr, af_pass_message));
1821 /* If ok is TRUE, we know we have got at least one good recipient, and must now
1822 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
1823 have a good recipient buffered up if we are pipelining. We don't want to waste
1824 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
1825 are pipelining. The responses are all handled by sync_responses(). */
1827 if (ok || (smtp_use_pipelining && !mua_wrapper))
1829 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
1830 if (count < 0) goto SEND_FAILED;
1831 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
1832 host, count, ob->address_retry_include_sender, pending_MAIL,
1833 ok? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
1835 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1836 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1839 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1840 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1841 case 0: break; /* No 2xx or 5xx, but no probs */
1843 case -1: goto END_OFF; /* Timeout on RCPT */
1844 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
1848 /* Save the first address of the next batch. */
1852 /* If there were no good recipients (but otherwise there have been no
1853 problems), just set ok TRUE, since we have handled address-specific errors
1854 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
1855 for handling the SMTP dot-handling protocol, flagging to apply to headers as
1856 well as body. Set the appropriate timeout value to be used for each chunk.
1857 (Haven't been able to make it work using select() for writing yet.) */
1859 if (!ok) ok = TRUE; else
1861 sigalrm_seen = FALSE;
1862 transport_write_timeout = ob->data_timeout;
1863 smtp_command = US"sending data block"; /* For error messages */
1864 DEBUG(D_transport|D_v)
1865 debug_printf(" SMTP>> writing message and terminating \".\"\n");
1866 transport_count = 0;
1867 #ifndef DISABLE_DKIM
1868 ok = dkim_transport_write_message(addrlist, inblock.sock,
1869 topt_use_crlf | topt_end_dot | topt_escape_headers |
1870 (tblock->body_only? topt_no_headers : 0) |
1871 (tblock->headers_only? topt_no_body : 0) |
1872 (tblock->return_path_add? topt_add_return_path : 0) |
1873 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1874 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1875 0, /* No size limit */
1876 tblock->add_headers, tblock->remove_headers,
1877 US".", US"..", /* Escaping strings */
1878 tblock->rewrite_rules, tblock->rewrite_existflags,
1879 ob->dkim_private_key, ob->dkim_domain, ob->dkim_selector,
1880 ob->dkim_canon, ob->dkim_strict, ob->dkim_sign_headers
1883 ok = transport_write_message(addrlist, inblock.sock,
1884 topt_use_crlf | topt_end_dot | topt_escape_headers |
1885 (tblock->body_only? topt_no_headers : 0) |
1886 (tblock->headers_only? topt_no_body : 0) |
1887 (tblock->return_path_add? topt_add_return_path : 0) |
1888 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1889 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1890 0, /* No size limit */
1891 tblock->add_headers, tblock->remove_headers,
1892 US".", US"..", /* Escaping strings */
1893 tblock->rewrite_rules, tblock->rewrite_existflags);
1896 /* transport_write_message() uses write() because it is called from other
1897 places to write to non-sockets. This means that under some OS (e.g. Solaris)
1898 it can exit with "Broken pipe" as its error. This really means that the
1899 socket got closed at the far end. */
1901 transport_write_timeout = 0; /* for subsequent transports */
1903 /* Failure can either be some kind of I/O disaster (including timeout),
1904 or the failure of a transport filter or the expansion of added headers. */
1908 buffer[0] = 0; /* There hasn't been a response */
1909 goto RESPONSE_FAILED;
1912 /* We used to send the terminating "." explicitly here, but because of
1913 buffering effects at both ends of TCP/IP connections, you don't gain
1914 anything by keeping it separate, so it might as well go in the final
1915 data buffer for efficiency. This is now done by setting the topt_end_dot
1918 smtp_command = US"end of data";
1920 #ifdef EXPERIMENTAL_PRDR
1921 /* For PRDR we optionally get a partial-responses warning
1922 * followed by the individual responses, before going on with
1923 * the overall response. If we don't get the warning then deal
1924 * with per non-PRDR. */
1927 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '3',
1929 if (!ok && errno == 0)
1932 case '2': prdr_active = FALSE;
1935 case '4': errno = ERRNO_DATA4XX;
1936 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1943 /* For non-PRDR SMTP, we now read a single response that applies to the
1944 whole message. If it is OK, then all the addresses have been delivered. */
1948 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1950 if (!ok && errno == 0 && buffer[0] == '4')
1952 errno = ERRNO_DATA4XX;
1953 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1957 /* For LMTP, we get back a response for every RCPT command that we sent;
1958 some may be accepted and some rejected. For those that get a response, their
1959 status is fixed; any that are accepted have been handed over, even if later
1960 responses crash - at least, that's how I read RFC 2033.
1962 If all went well, mark the recipient addresses as completed, record which
1963 host/IPaddress they were delivered to, and cut out RSET when sending another
1964 message down the same channel. Write the completed addresses to the journal
1965 now so that they are recorded in case there is a crash of hardware or
1966 software before the spool gets updated. Also record the final SMTP
1967 confirmation if needed (for SMTP only). */
1972 int delivery_time = (int)(time(NULL) - start_delivery_time);
1975 uschar *conf = NULL;
1978 /* Make a copy of the host if it is local to this invocation
1979 of the transport. */
1983 thost = store_get(sizeof(host_item));
1985 thost->name = string_copy(host->name);
1986 thost->address = string_copy(host->address);
1990 /* Set up confirmation if needed - applies only to SMTP */
1993 #ifndef EXPERIMENTAL_TPDA
1994 (log_extra_selector & LX_smtp_confirmation) != 0 &&
1999 uschar *s = string_printing(buffer);
2000 conf = (s == buffer)? (uschar *)string_copy(s) : s;
2003 /* Process all transported addresses - for LMTP or PRDR, read a status for
2006 for (addr = addrlist; addr != first_addr; addr = addr->next)
2008 if (addr->transport_return != PENDING_OK) continue;
2010 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
2011 remaining addresses. Otherwise, it's a return code for just the one
2012 address. For temporary errors, add a retry item for the address so that
2013 it doesn't get tried again too soon. */
2015 #ifdef EXPERIMENTAL_PRDR
2016 if (lmtp || prdr_active)
2021 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2024 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
2025 addr->message = string_sprintf(
2026 #ifdef EXPERIMENTAL_PRDR
2027 "%s error after %s: %s", prdr_active ? "PRDR":"LMTP",
2029 "LMTP error after %s: %s",
2031 big_buffer, string_printing(buffer));
2032 setflag(addr, af_pass_message); /* Allow message to go to user */
2033 if (buffer[0] == '5')
2034 addr->transport_return = FAIL;
2037 errno = ERRNO_DATA4XX;
2038 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2039 addr->transport_return = DEFER;
2040 #ifdef EXPERIMENTAL_PRDR
2043 retry_add_item(addr, addr->address_retry_key, 0);
2047 completed_address = TRUE; /* NOW we can set this flag */
2048 if ((log_extra_selector & LX_smtp_confirmation) != 0)
2050 uschar *s = string_printing(buffer);
2051 conf = (s == buffer)? (uschar *)string_copy(s) : s;
2055 /* SMTP, or success return from LMTP for this address. Pass back the
2056 actual host that was used. */
2058 addr->transport_return = OK;
2059 addr->more_errno = delivery_time;
2060 addr->host_used = thost;
2061 addr->special_action = flag;
2062 addr->message = conf;
2063 #ifdef EXPERIMENTAL_PRDR
2064 if (prdr_active) addr->flags |= af_prdr_used;
2068 #ifdef EXPERIMENTAL_PRDR
2072 /* Update the journal. For homonymic addresses, use the base address plus
2073 the transport name. See lots of comments in deliver.c about the reasons
2074 for the complications when homonyms are involved. Just carry on after
2075 write error, as it may prove possible to update the spool file later. */
2077 if (testflag(addr, af_homonym))
2078 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2080 sprintf(CS buffer, "%.500s\n", addr->unique);
2082 DEBUG(D_deliver) debug_printf("journalling %s", buffer);
2083 len = Ustrlen(CS buffer);
2084 if (write(journal_fd, buffer, len) != len)
2085 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2086 "%s: %s", buffer, strerror(errno));
2090 #ifdef EXPERIMENTAL_PRDR
2093 /* PRDR - get the final, overall response. For any non-success
2094 upgrade all the address statuses. */
2095 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2099 if(errno == 0 && buffer[0] == '4')
2101 errno = ERRNO_DATA4XX;
2102 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2104 for (addr = addrlist; addr != first_addr; addr = addr->next)
2105 if (buffer[0] == '5' || addr->transport_return == OK)
2106 addr->transport_return = PENDING_OK; /* allow set_errno action */
2107 goto RESPONSE_FAILED;
2110 /* Update the journal, or setup retry. */
2111 for (addr = addrlist; addr != first_addr; addr = addr->next)
2112 if (addr->transport_return == OK)
2114 if (testflag(addr, af_homonym))
2115 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2117 sprintf(CS buffer, "%.500s\n", addr->unique);
2119 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s", buffer);
2120 len = Ustrlen(CS buffer);
2121 if (write(journal_fd, buffer, len) != len)
2122 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2123 "%s: %s", buffer, strerror(errno));
2125 else if (addr->transport_return == DEFER)
2126 retry_add_item(addr, addr->address_retry_key, -2);
2130 /* Ensure the journal file is pushed out to disk. */
2132 if (EXIMfsync(journal_fd) < 0)
2133 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
2139 /* Handle general (not specific to one address) failures here. The value of ok
2140 is used to skip over this code on the falling through case. A timeout causes a
2141 deferral. Other errors may defer or fail according to the response code, and
2142 may set up a special errno value, e.g. after connection chopped, which is
2143 assumed if errno == 0 and there is no text in the buffer. If control reaches
2144 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
2145 the problem is not related to this specific message. */
2154 send_quit = check_response(host, &save_errno, addrlist->more_errno,
2155 buffer, &code, &message, &pass_message);
2161 message = US string_sprintf("send() to %s [%s] failed: %s",
2162 host->name, host->address, strerror(save_errno));
2166 /* This label is jumped to directly when a TLS negotiation has failed,
2167 or was not done for a host for which it is required. Values will be set
2168 in message and save_errno, and setting_up will always be true. Treat as
2169 a temporary error. */
2176 /* If the failure happened while setting up the call, see if the failure was
2177 a 5xx response (this will either be on connection, or following HELO - a 5xx
2178 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
2179 never going to accept them. For other errors during setting up (timeouts or
2180 whatever), defer all addresses, and yield DEFER, so that the host is not
2181 tried again for a while. */
2184 ok = FALSE; /* For when reached by GOTO */
2190 set_errno(addrlist, save_errno, message, FAIL, pass_message);
2194 set_errno(addrlist, save_errno, message, DEFER, pass_message);
2199 /* We want to handle timeouts after MAIL or "." and loss of connection after
2200 "." specially. They can indicate a problem with the sender address or with
2201 the contents of the message rather than a real error on the connection. These
2202 cases are treated in the same way as a 4xx response. This next bit of code
2203 does the classification. */
2214 message_error = TRUE;
2218 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
2219 Ustrncmp(smtp_command,"end ",4) == 0;
2222 case ERRNO_SMTPCLOSED:
2223 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
2227 message_error = FALSE;
2231 /* Handle the cases that are treated as message errors. These are:
2233 (a) negative response or timeout after MAIL
2234 (b) negative response after DATA
2235 (c) negative response or timeout or dropped connection after "."
2237 It won't be a negative response or timeout after RCPT, as that is dealt
2238 with separately above. The action in all cases is to set an appropriate
2239 error code for all the addresses, but to leave yield set to OK because the
2240 host itself has not failed. Of course, it might in practice have failed
2241 when we've had a timeout, but if so, we'll discover that at the next
2242 delivery attempt. For a temporary error, set the message_defer flag, and
2243 write to the logs for information if this is not the last host. The error
2244 for the last host will be logged as part of the address's log line. */
2248 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
2249 set_errno(addrlist, save_errno, message, (code == '5')? FAIL : DEFER,
2252 /* If there's an errno, the message contains just the identity of
2255 if (code != '5') /* Anything other than 5 is treated as temporary */
2258 message = US string_sprintf("%s: %s", message, strerror(save_errno));
2259 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
2260 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
2261 *message_defer = TRUE;
2265 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
2266 ".", or some other transportation error. We defer all addresses and yield
2267 DEFER, except for the case of failed add_headers expansion, or a transport
2268 filter failure, when the yield should be ERROR, to stop it trying other
2273 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
2274 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
2275 set_errno(addrlist, save_errno, message, DEFER, pass_message);
2281 /* If all has gone well, send_quit will be set TRUE, implying we can end the
2282 SMTP session tidily. However, if there were too many addresses to send in one
2283 message (indicated by first_addr being non-NULL) we want to carry on with the
2284 rest of them. Also, it is desirable to send more than one message down the SMTP
2285 connection if there are several waiting, provided we haven't already sent so
2286 many as to hit the configured limit. The function transport_check_waiting looks
2287 for a waiting message and returns its id. Then transport_pass_socket tries to
2288 set up a continued delivery by passing the socket on to another process. The
2289 variable send_rset is FALSE if a message has just been successfully transfered.
2291 If we are already sending down a continued channel, there may be further
2292 addresses not yet delivered that are aimed at the same host, but which have not
2293 been passed in this run of the transport. In this case, continue_more will be
2294 true, and all we should do is send RSET if necessary, and return, leaving the
2297 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
2298 do not want to continue with other messages down the same channel, because that
2299 can lead to looping between two or more messages, all with the same,
2300 temporarily failing address(es). [The retry information isn't updated yet, so
2301 new processes keep on trying.] We probably also don't want to try more of this
2302 message's addresses either.
2304 If we have started a TLS session, we have to end it before passing the
2305 connection to a new process. However, not all servers can handle this (Exim
2306 can), so we do not pass such a connection on if the host matches
2307 hosts_nopass_tls. */
2310 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
2311 "yield=%d first_address is %sNULL\n", ok, send_quit, send_rset,
2312 continue_more, yield, (first_addr == NULL)? "":"not ");
2314 if (completed_address && ok && send_quit)
2317 if (first_addr != NULL || continue_more ||
2319 (tls_out.active < 0 ||
2320 verify_check_this_host(&(ob->hosts_nopass_tls), NULL, host->name,
2321 host->address, NULL) != OK)
2323 transport_check_waiting(tblock->name, host->name,
2324 tblock->connection_max_messages, new_message_id, &more)
2332 if (! (ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
2334 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
2335 host->address, strerror(save_errno));
2338 else if (! (ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2339 ob->command_timeout)))
2342 send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
2346 DEBUG(D_transport) debug_printf("%s\n", msg);
2351 /* Either RSET was not needed, or it succeeded */
2355 if (first_addr != NULL) /* More addresses still to be sent */
2356 { /* in this run of the transport */
2357 continue_sequence++; /* Causes * in logging */
2360 if (continue_more) return yield; /* More addresses for another run */
2362 /* Pass the socket to a new Exim process. Before doing so, we must shut
2363 down TLS. Not all MTAs allow for the continuation of the SMTP session
2364 when TLS is shut down. We test for this by sending a new EHLO. If we
2365 don't get a good response, we don't attempt to pass the socket on. */
2368 if (tls_out.active >= 0)
2370 tls_close(FALSE, TRUE);
2374 ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
2375 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2376 ob->command_timeout);
2380 /* If the socket is successfully passed, we musn't send QUIT (or
2381 indeed anything!) from here. */
2383 if (ok && transport_pass_socket(tblock->name, host->name, host->address,
2384 new_message_id, inblock.sock))
2390 /* If RSET failed and there are addresses left, they get deferred. */
2392 else set_errno(first_addr, errno, msg, DEFER, FALSE);
2396 /* End off tidily with QUIT unless the connection has died or the socket has
2397 been passed to another process. There has been discussion on the net about what
2398 to do after sending QUIT. The wording of the RFC suggests that it is necessary
2399 to wait for a response, but on the other hand, there isn't anything one can do
2400 with an error response, other than log it. Exim used to do that. However,
2401 further discussion suggested that it is positively advantageous not to wait for
2402 the response, but to close the session immediately. This is supposed to move
2403 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
2404 load from the server. (Hosts that are both servers and clients may not see much
2405 difference, of course.) Further discussion indicated that this was safe to do
2406 on Unix systems which have decent implementations of TCP/IP that leave the
2407 connection around for a while (TIME_WAIT) after the application has gone away.
2408 This enables the response sent by the server to be properly ACKed rather than
2409 timed out, as can happen on broken TCP/IP implementations on other OS.
2411 This change is being made on 31-Jul-98. After over a year of trouble-free
2412 operation, the old commented-out code was removed on 17-Sep-99. */
2415 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2420 tls_close(FALSE, TRUE);
2423 /* Close the socket, and return the appropriate value, first setting
2424 works because the NULL setting is passed back to the calling process, and
2425 remote_max_parallel is forced to 1 when delivering over an existing connection,
2427 If all went well and continue_more is set, we shouldn't actually get here if
2428 there are further addresses, as the return above will be taken. However,
2429 writing RSET might have failed, or there may be other addresses whose hosts are
2430 specified in the transports, and therefore not visible at top level, in which
2431 case continue_more won't get set. */
2433 (void)close(inblock.sock);
2434 continue_transport = NULL;
2435 continue_hostname = NULL;
2442 /*************************************************
2443 * Closedown entry point *
2444 *************************************************/
2446 /* This function is called when exim is passed an open smtp channel
2447 from another incarnation, but the message which it has been asked
2448 to deliver no longer exists. The channel is on stdin.
2450 We might do fancy things like looking for another message to send down
2451 the channel, but if the one we sought has gone, it has probably been
2452 delivered by some other process that itself will seek further messages,
2453 so just close down our connection.
2455 Argument: pointer to the transport instance block
2460 smtp_transport_closedown(transport_instance *tblock)
2462 smtp_transport_options_block *ob =
2463 (smtp_transport_options_block *)(tblock->options_block);
2464 smtp_inblock inblock;
2465 smtp_outblock outblock;
2467 uschar inbuffer[4096];
2468 uschar outbuffer[16];
2470 inblock.sock = fileno(stdin);
2471 inblock.buffer = inbuffer;
2472 inblock.buffersize = sizeof(inbuffer);
2473 inblock.ptr = inbuffer;
2474 inblock.ptrend = inbuffer;
2476 outblock.sock = inblock.sock;
2477 outblock.buffersize = sizeof(outbuffer);
2478 outblock.buffer = outbuffer;
2479 outblock.ptr = outbuffer;
2480 outblock.cmd_count = 0;
2481 outblock.authenticating = FALSE;
2483 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2484 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2485 ob->command_timeout);
2486 (void)close(inblock.sock);
2491 /*************************************************
2492 * Prepare addresses for delivery *
2493 *************************************************/
2495 /* This function is called to flush out error settings from previous delivery
2496 attempts to other hosts. It also records whether we got here via an MX record
2497 or not in the more_errno field of the address. We are interested only in
2498 addresses that are still marked DEFER - others may have got delivered to a
2499 previously considered IP address. Set their status to PENDING_DEFER to indicate
2500 which ones are relevant this time.
2503 addrlist the list of addresses
2504 host the host we are delivering to
2506 Returns: the first address for this delivery
2509 static address_item *
2510 prepare_addresses(address_item *addrlist, host_item *host)
2512 address_item *first_addr = NULL;
2514 for (addr = addrlist; addr != NULL; addr = addr->next)
2516 if (addr->transport_return != DEFER) continue;
2517 if (first_addr == NULL) first_addr = addr;
2518 addr->transport_return = PENDING_DEFER;
2519 addr->basic_errno = 0;
2520 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
2521 addr->message = NULL;
2523 addr->cipher = NULL;
2524 addr->ourcert = NULL;
2525 addr->peercert = NULL;
2526 addr->peerdn = NULL;
2534 /*************************************************
2535 * Main entry point *
2536 *************************************************/
2538 /* See local README for interface details. As this is a remote transport, it is
2539 given a chain of addresses to be delivered in one connection, if possible. It
2540 always returns TRUE, indicating that each address has its own independent
2541 status set, except if there is a setting up problem, in which case it returns
2545 smtp_transport_entry(
2546 transport_instance *tblock, /* data for this instantiation */
2547 address_item *addrlist) /* addresses we are working on */
2551 int hosts_defer = 0;
2553 int hosts_looked_up = 0;
2554 int hosts_retry = 0;
2555 int hosts_serial = 0;
2556 int hosts_total = 0;
2557 int total_hosts_tried = 0;
2559 BOOL expired = TRUE;
2560 BOOL continuing = continue_hostname != NULL;
2561 uschar *expanded_hosts = NULL;
2563 uschar *tid = string_sprintf("%s transport", tblock->name);
2564 smtp_transport_options_block *ob =
2565 (smtp_transport_options_block *)(tblock->options_block);
2566 host_item *hostlist = addrlist->host_list;
2567 host_item *host = NULL;
2571 debug_printf("%s transport entered\n", tblock->name);
2572 for (addr = addrlist; addr != NULL; addr = addr->next)
2573 debug_printf(" %s\n", addr->address);
2574 if (continuing) debug_printf("already connected to %s [%s]\n",
2575 continue_hostname, continue_host_address);
2578 /* Set the flag requesting that these hosts be added to the waiting
2579 database if the delivery fails temporarily or if we are running with
2580 queue_smtp or a 2-stage queue run. This gets unset for certain
2581 kinds of error, typically those that are specific to the message. */
2583 update_waiting = TRUE;
2585 /* If a host list is not defined for the addresses - they must all have the
2586 same one in order to be passed to a single transport - or if the transport has
2587 a host list with hosts_override set, use the host list supplied with the
2588 transport. It is an error for this not to exist. */
2590 if (hostlist == NULL || (ob->hosts_override && ob->hosts != NULL))
2592 if (ob->hosts == NULL)
2594 addrlist->message = string_sprintf("%s transport called with no hosts set",
2596 addrlist->transport_return = PANIC;
2597 return FALSE; /* Only top address has status */
2600 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
2603 /* If the transport's host list contains no '$' characters, and we are not
2604 randomizing, it is fixed and therefore a chain of hosts can be built once
2605 and for all, and remembered for subsequent use by other calls to this
2606 transport. If, on the other hand, the host list does contain '$', or we are
2607 randomizing its order, we have to rebuild it each time. In the fixed case,
2608 as the hosts string will never be used again, it doesn't matter that we
2609 replace all the : characters with zeros. */
2611 if (ob->hostlist == NULL)
2613 uschar *s = ob->hosts;
2615 if (Ustrchr(s, '$') != NULL)
2617 expanded_hosts = expand_string(s);
2618 if (expanded_hosts == NULL)
2620 addrlist->message = string_sprintf("failed to expand list of hosts "
2621 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
2622 addrlist->transport_return = search_find_defer? DEFER : PANIC;
2623 return FALSE; /* Only top address has status */
2625 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
2626 "\"%s\"\n", s, expanded_hosts);
2630 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
2632 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
2634 /* Check that the expansion yielded something useful. */
2635 if (hostlist == NULL)
2638 string_sprintf("%s transport has empty hosts setting", tblock->name);
2639 addrlist->transport_return = PANIC;
2640 return FALSE; /* Only top address has status */
2643 /* If there was no expansion of hosts, save the host list for
2646 if (expanded_hosts == NULL) ob->hostlist = hostlist;
2649 /* This is not the first time this transport has been run in this delivery;
2650 the host list was built previously. */
2652 else hostlist = ob->hostlist;
2655 /* The host list was supplied with the address. If hosts_randomize is set, we
2656 must sort it into a random order if it did not come from MX records and has not
2657 already been randomized (but don't bother if continuing down an existing
2660 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continuing)
2662 host_item *newlist = NULL;
2663 while (hostlist != NULL)
2665 host_item *h = hostlist;
2666 hostlist = hostlist->next;
2668 h->sort_key = random_number(100);
2670 if (newlist == NULL)
2675 else if (h->sort_key < newlist->sort_key)
2682 host_item *hh = newlist;
2683 while (hh->next != NULL)
2685 if (h->sort_key < hh->next->sort_key) break;
2693 hostlist = addrlist->host_list = newlist;
2697 /* Sort out the default port. */
2699 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
2702 /* For each host-plus-IP-address on the list:
2704 . If this is a continued delivery and the host isn't the one with the
2705 current connection, skip.
2707 . If the status is unusable (i.e. previously failed or retry checked), skip.
2709 . If no IP address set, get the address, either by turning the name into
2710 an address, calling gethostbyname if gethostbyname is on, or by calling
2711 the DNS. The DNS may yield multiple addresses, in which case insert the
2712 extra ones into the list.
2714 . Get the retry data if not previously obtained for this address and set the
2715 field which remembers the state of this address. Skip if the retry time is
2716 not reached. If not, remember whether retry data was found. The retry string
2717 contains both the name and the IP address.
2719 . Scan the list of addresses and mark those whose status is DEFER as
2720 PENDING_DEFER. These are the only ones that will be processed in this cycle
2723 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
2724 Some addresses may be successfully delivered, others may fail, and yet
2725 others may get temporary errors and so get marked DEFER.
2727 . The return from the delivery attempt is OK if a connection was made and a
2728 valid SMTP dialogue was completed. Otherwise it is DEFER.
2730 . If OK, add a "remove" retry item for this host/IPaddress, if any.
2732 . If fail to connect, or other defer state, add a retry item.
2734 . If there are any addresses whose status is still DEFER, carry on to the
2735 next host/IPaddress, unless we have tried the number of hosts given
2736 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
2737 there is some fancy logic for hosts_max_try that means its limit can be
2738 overstepped in some circumstances.
2740 If we get to the end of the list, all hosts have deferred at least one address,
2741 or not reached their retry times. If delay_after_cutoff is unset, it requests a
2742 delivery attempt to those hosts whose last try was before the arrival time of
2743 the current message. To cope with this, we have to go round the loop a second
2744 time. After that, set the status and error data for any addresses that haven't
2745 had it set already. */
2747 for (cutoff_retry = 0; expired &&
2748 cutoff_retry < ((ob->delay_after_cutoff)? 1 : 2);
2751 host_item *nexthost = NULL;
2752 int unexpired_hosts_tried = 0;
2754 for (host = hostlist;
2756 unexpired_hosts_tried < ob->hosts_max_try &&
2757 total_hosts_tried < ob->hosts_max_try_hardlimit;
2763 BOOL serialized = FALSE;
2764 BOOL host_is_expired = FALSE;
2765 BOOL message_defer = FALSE;
2766 BOOL ifchanges = FALSE;
2767 BOOL some_deferred = FALSE;
2768 address_item *first_addr = NULL;
2769 uschar *interface = NULL;
2770 uschar *retry_host_key = NULL;
2771 uschar *retry_message_key = NULL;
2772 uschar *serialize_key = NULL;
2774 /* Default next host is next host. :-) But this can vary if the
2775 hosts_max_try limit is hit (see below). It may also be reset if a host
2776 address is looked up here (in case the host was multihomed). */
2778 nexthost = host->next;
2780 /* If the address hasn't yet been obtained from the host name, look it up
2781 now, unless the host is already marked as unusable. If it is marked as
2782 unusable, it means that the router was unable to find its IP address (in
2783 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
2784 the lookup failed last time. We don't get this far if *all* MX records
2785 point to non-existent hosts; that is treated as a hard error.
2787 We can just skip this host entirely. When the hosts came from the router,
2788 the address will timeout based on the other host(s); when the address is
2789 looked up below, there is an explicit retry record added.
2791 Note that we mustn't skip unusable hosts if the address is not unset; they
2792 may be needed as expired hosts on the 2nd time round the cutoff loop. */
2794 if (host->address == NULL)
2796 int new_port, flags;
2798 uschar *canonical_name;
2800 if (host->status >= hstatus_unusable)
2802 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
2807 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
2809 /* The host name is permitted to have an attached port. Find it, and
2810 strip it from the name. Just remember it for now. */
2812 new_port = host_item_get_port(host);
2814 /* Count hosts looked up */
2818 /* Find by name if so configured, or if it's an IP address. We don't
2819 just copy the IP address, because we need the test-for-local to happen. */
2821 flags = HOST_FIND_BY_A;
2822 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
2823 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
2825 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
2826 rc = host_find_byname(host, NULL, flags, &canonical_name, TRUE);
2828 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
2829 ob->dnssec_request_domains, ob->dnssec_require_domains,
2830 &canonical_name, NULL);
2832 /* Update the host (and any additional blocks, resulting from
2833 multihoming) with a host-specific port, if any. */
2835 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
2837 /* Failure to find the host at this time (usually DNS temporary failure)
2838 is really a kind of routing failure rather than a transport failure.
2839 Therefore we add a retry item of the routing kind, not to stop us trying
2840 to look this name up here again, but to ensure the address gets timed
2841 out if the failures go on long enough. A complete failure at this point
2842 commonly points to a configuration error, but the best action is still
2843 to carry on for the next host. */
2845 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
2847 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
2849 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
2850 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
2851 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
2852 host->status = hstatus_unusable;
2854 for (addr = addrlist; addr != NULL; addr = addr->next)
2856 if (addr->transport_return != DEFER) continue;
2857 addr->basic_errno = ERRNO_UNKNOWNHOST;
2859 string_sprintf("failed to lookup IP address for %s", host->name);
2864 /* If the host is actually the local host, we may have a problem, or
2865 there may be some cunning configuration going on. In the problem case,
2866 log things and give up. The default transport status is already DEFER. */
2868 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
2870 for (addr = addrlist; addr != NULL; addr = addr->next)
2872 addr->basic_errno = 0;
2873 addr->message = string_sprintf("%s transport found host %s to be "
2874 "local", tblock->name, host->name);
2878 } /* End of block for IP address lookup */
2880 /* If this is a continued delivery, we are interested only in the host
2881 which matches the name of the existing open channel. The check is put
2882 here after the local host lookup, in case the name gets expanded as a
2883 result of the lookup. Set expired FALSE, to save the outer loop executing
2886 if (continuing && (Ustrcmp(continue_hostname, host->name) != 0 ||
2887 Ustrcmp(continue_host_address, host->address) != 0))
2890 continue; /* With next host */
2893 /* Reset the default next host in case a multihomed host whose addresses
2894 are not looked up till just above added to the host list. */
2896 nexthost = host->next;
2898 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
2899 domain is in queue_smtp_domains, we don't actually want to attempt any
2900 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
2901 there is a lookup defer in queue_smtp_domains, proceed as if the domain
2902 were not in it. We don't want to hold up all SMTP deliveries! Except when
2903 doing a two-stage queue run, don't do this if forcing. */
2905 if ((!deliver_force || queue_2stage) && (queue_smtp ||
2906 match_isinlist(addrlist->domain, &queue_smtp_domains, 0,
2907 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
2910 for (addr = addrlist; addr != NULL; addr = addr->next)
2912 if (addr->transport_return != DEFER) continue;
2913 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
2915 continue; /* With next host */
2918 /* Count hosts being considered - purely for an intelligent comment
2919 if none are usable. */
2923 /* Set $host and $host address now in case they are needed for the
2924 interface expansion or the serialize_hosts check; they remain set if an
2925 actual delivery happens. */
2927 deliver_host = host->name;
2928 deliver_host_address = host->address;
2930 /* Set up a string for adding to the retry key if the port number is not
2931 the standard SMTP port. A host may have its own port setting that overrides
2934 pistring = string_sprintf(":%d", (host->port == PORT_NONE)?
2936 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
2938 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
2939 string changes upon expansion, we must add it to the key that is used for
2940 retries, because connections to the same host from a different interface
2941 should be treated separately. */
2943 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET : AF_INET6;
2944 if (!smtp_get_interface(ob->interface, host_af, addrlist, &ifchanges,
2947 if (ifchanges) pistring = string_sprintf("%s/%s", pistring, interface);
2949 /* The first time round the outer loop, check the status of the host by
2950 inspecting the retry data. The second time round, we are interested only
2951 in expired hosts that haven't been tried since this message arrived. */
2953 if (cutoff_retry == 0)
2955 /* Ensure the status of the address is set by checking retry data if
2956 necessary. There maybe host-specific retry data (applicable to all
2957 messages) and also data for retries of a specific message at this host.
2958 If either of these retry records are actually read, the keys used are
2959 returned to save recomputing them later. */
2961 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
2962 ob->retry_include_ip_address, &retry_host_key, &retry_message_key);
2964 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
2965 (host->address == NULL)? US"" : host->address, pistring,
2966 (host->status == hstatus_usable)? "usable" :
2967 (host->status == hstatus_unusable)? "unusable" :
2968 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
2970 /* Skip this address if not usable at this time, noting if it wasn't
2971 actually expired, both locally and in the address. */
2973 switch (host->status)
2975 case hstatus_unusable:
2977 setflag(addrlist, af_retry_skipped);
2980 case hstatus_unusable_expired:
2983 case hwhy_retry: hosts_retry++; break;
2984 case hwhy_failed: hosts_fail++; break;
2985 case hwhy_deferred: hosts_defer++; break;
2988 /* If there was a retry message key, implying that previously there
2989 was a message-specific defer, we don't want to update the list of
2990 messages waiting for these hosts. */
2992 if (retry_message_key != NULL) update_waiting = FALSE;
2993 continue; /* With the next host or IP address */
2997 /* Second time round the loop: if the address is set but expired, and
2998 the message is newer than the last try, let it through. */
3002 if (host->address == NULL ||
3003 host->status != hstatus_unusable_expired ||
3004 host->last_try > received_time)
3007 debug_printf("trying expired host %s [%s]%s\n",
3008 host->name, host->address, pistring);
3009 host_is_expired = TRUE;
3012 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
3013 it remains TRUE only if all hosts are expired and none are actually tried.
3018 /* If this host is listed as one to which access must be serialized,
3019 see if another Exim process has a connection to it, and if so, skip
3020 this host. If not, update the database to record our connection to it
3021 and remember this for later deletion. Do not do any of this if we are
3022 sending the message down a pre-existing connection. */
3025 verify_check_this_host(&(ob->serialize_hosts), NULL, host->name,
3026 host->address, NULL) == OK)
3028 serialize_key = string_sprintf("host-serialize-%s", host->name);
3029 if (!enq_start(serialize_key))
3032 debug_printf("skipping host %s because another Exim process "
3033 "is connected to it\n", host->name);
3040 /* OK, we have an IP address that is not waiting for its retry time to
3041 arrive (it might be expired) OR (second time round the loop) we have an
3042 expired host that hasn't been tried since the message arrived. Have a go
3043 at delivering the message to it. First prepare the addresses by flushing
3044 out the result of previous attempts, and finding the first address that
3045 is still to be delivered. */
3047 first_addr = prepare_addresses(addrlist, host);
3049 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
3050 message_id, host->name, host->address, addrlist->address,
3051 (addrlist->next == NULL)? "" : ", ...");
3053 set_process_info("delivering %s to %s [%s] (%s%s)",
3054 message_id, host->name, host->address, addrlist->address,
3055 (addrlist->next == NULL)? "" : ", ...");
3057 /* This is not for real; don't do the delivery. If there are
3058 any remaining hosts, list them. */
3063 set_errno(addrlist, 0, NULL, OK, FALSE);
3064 for (addr = addrlist; addr != NULL; addr = addr->next)
3066 addr->host_used = host;
3067 addr->special_action = '*';
3068 addr->message = US"delivery bypassed by -N option";
3072 debug_printf("*** delivery by %s transport bypassed by -N option\n"
3073 "*** host and remaining hosts:\n", tblock->name);
3074 for (host2 = host; host2 != NULL; host2 = host2->next)
3075 debug_printf(" %s [%s]\n", host2->name,
3076 (host2->address == NULL)? US"unset" : host2->address);
3081 /* This is for real. If the host is expired, we don't count it for
3082 hosts_max_retry. This ensures that all hosts must expire before an address
3083 is timed out, unless hosts_max_try_hardlimit (which protects against
3084 lunatic DNS configurations) is reached.
3086 If the host is not expired and we are about to hit the hosts_max_retry
3087 limit, check to see if there is a subsequent hosts with a different MX
3088 value. If so, make that the next host, and don't count this one. This is a
3089 heuristic to make sure that different MXs do get tried. With a normal kind
3090 of retry rule, they would get tried anyway when the earlier hosts were
3091 delayed, but if the domain has a "retry every time" type of rule - as is
3092 often used for the the very large ISPs, that won't happen. */
3096 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
3100 debug_printf("hosts_max_try limit reached with this host\n");
3101 for (h = host; h != NULL; h = h->next)
3102 if (h->mx != host->mx) break;
3106 unexpired_hosts_tried--;
3107 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
3108 "and will be tried\n");
3112 /* Attempt the delivery. */
3114 total_hosts_tried++;
3115 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
3116 expanded_hosts != NULL, &message_defer, FALSE);
3119 OK => connection made, each address contains its result;
3120 message_defer is set for message-specific defers (when all
3121 recipients are marked defer)
3122 DEFER => there was a non-message-specific delivery problem;
3123 ERROR => there was a problem setting up the arguments for a filter,
3124 or there was a problem with expanding added headers
3127 /* If the result is not OK, there was a non-message-specific problem.
3128 If the result is DEFER, we need to write to the logs saying what happened
3129 for this particular host, except in the case of authentication and TLS
3130 failures, where the log has already been written. If all hosts defer a
3131 general message is written at the end. */
3133 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL &&
3134 first_addr->basic_errno != ERRNO_TLSFAILURE)
3135 write_logs(first_addr, host);
3137 #ifdef EXPERIMENTAL_TPDA
3139 tpda_deferred(ob, first_addr, host);
3142 /* If STARTTLS was accepted, but there was a failure in setting up the
3143 TLS session (usually a certificate screwup), and the host is not in
3144 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
3145 TLS forcibly turned off. We have to start from scratch with a new SMTP
3146 connection. That's why the retry is done from here, not from within
3147 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
3148 session, so the in-clear transmission after those errors, if permitted,
3149 happens inside smtp_deliver().] */
3152 if (rc == DEFER && first_addr->basic_errno == ERRNO_TLSFAILURE &&
3153 ob->tls_tempfail_tryclear &&
3154 verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
3155 host->address, NULL) != OK)
3157 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
3158 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
3159 first_addr = prepare_addresses(addrlist, host);
3160 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
3161 expanded_hosts != NULL, &message_defer, TRUE);
3162 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
3163 write_logs(first_addr, host);
3164 #ifdef EXPERIMENTAL_TPDA
3166 tpda_deferred(ob, first_addr, host);
3172 /* Delivery attempt finished */
3174 rs = (rc == OK)? US"OK" : (rc == DEFER)? US"DEFER" : (rc == ERROR)?
3177 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
3178 message_id, host->name, host->address, addrlist->address,
3179 (addrlist->next == NULL)? "" : " (& others)", rs);
3181 /* Release serialization if set up */
3183 if (serialized) enq_end(serialize_key);
3185 /* If the result is DEFER, or if a host retry record is known to exist, we
3186 need to add an item to the retry chain for updating the retry database
3187 at the end of delivery. We only need to add the item to the top address,
3188 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
3189 for any other delivery attempts using the same address. (It is copied into
3190 the unusable tree at the outer level, so even if different address blocks
3191 contain the same address, it still won't get tried again.) */
3193 if (rc == DEFER || retry_host_key != NULL)
3195 int delete_flag = (rc != DEFER)? rf_delete : 0;
3196 if (retry_host_key == NULL)
3198 retry_host_key = ob->retry_include_ip_address?
3199 string_sprintf("T:%S:%s%s", host->name, host->address, pistring) :
3200 string_sprintf("T:%S%s", host->name, pistring);
3203 /* If a delivery of another message over an existing SMTP connection
3204 yields DEFER, we do NOT set up retry data for the host. This covers the
3205 case when there are delays in routing the addresses in the second message
3206 that are so long that the server times out. This is alleviated by not
3207 routing addresses that previously had routing defers when handling an
3208 existing connection, but even so, this case may occur (e.g. if a
3209 previously happily routed address starts giving routing defers). If the
3210 host is genuinely down, another non-continued message delivery will
3211 notice it soon enough. */
3213 if (delete_flag != 0 || !continuing)
3214 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
3216 /* We may have tried an expired host, if its retry time has come; ensure
3217 the status reflects the expiry for the benefit of any other addresses. */
3221 host->status = (host_is_expired)?
3222 hstatus_unusable_expired : hstatus_unusable;
3223 host->why = hwhy_deferred;
3227 /* If message_defer is set (host was OK, but every recipient got deferred
3228 because of some message-specific problem), or if that had happened
3229 previously so that a message retry key exists, add an appropriate item
3230 to the retry chain. Note that if there was a message defer but now there is
3231 a host defer, the message defer record gets deleted. That seems perfectly
3232 reasonable. Also, stop the message from being remembered as waiting
3233 for specific hosts. */
3235 if (message_defer || retry_message_key != NULL)
3237 int delete_flag = message_defer? 0 : rf_delete;
3238 if (retry_message_key == NULL)
3240 retry_message_key = ob->retry_include_ip_address?
3241 string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
3243 string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
3245 retry_add_item(addrlist, retry_message_key,
3246 rf_message | rf_host | delete_flag);
3247 update_waiting = FALSE;
3250 /* Any return other than DEFER (that is, OK or ERROR) means that the
3251 addresses have got their final statuses filled in for this host. In the OK
3252 case, see if any of them are deferred. */
3256 for (addr = addrlist; addr != NULL; addr = addr->next)
3258 if (addr->transport_return == DEFER)
3260 some_deferred = TRUE;
3266 /* If no addresses deferred or the result was ERROR, return. We do this for
3267 ERROR because a failing filter set-up or add_headers expansion is likely to
3268 fail for any host we try. */
3270 if (rc == ERROR || (rc == OK && !some_deferred))
3272 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3273 return TRUE; /* Each address has its status */
3276 /* If the result was DEFER or some individual addresses deferred, let
3277 the loop run to try other hosts with the deferred addresses, except for the
3278 case when we were trying to deliver down an existing channel and failed.
3279 Don't try any other hosts in this case. */
3281 if (continuing) break;
3283 /* If the whole delivery, or some individual addresses, were deferred and
3284 there are more hosts that could be tried, do not count this host towards
3285 the hosts_max_try limit if the age of the message is greater than the
3286 maximum retry time for this host. This means we may try try all hosts,
3287 ignoring the limit, when messages have been around for some time. This is
3288 important because if we don't try all hosts, the address will never time
3289 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
3291 if ((rc == DEFER || some_deferred) && nexthost != NULL)
3294 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
3296 if (retry != NULL && retry->rules != NULL)
3298 retry_rule *last_rule;
3299 for (last_rule = retry->rules;
3300 last_rule->next != NULL;
3301 last_rule = last_rule->next);
3302 timedout = time(NULL) - received_time > last_rule->timeout;
3304 else timedout = TRUE; /* No rule => timed out */
3308 unexpired_hosts_tried--;
3309 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
3310 "hosts_max_try (message older than host's retry time)\n");
3313 } /* End of loop for trying multiple hosts. */
3315 /* This is the end of the loop that repeats iff expired is TRUE and
3316 ob->delay_after_cutoff is FALSE. The second time round we will
3317 try those hosts that haven't been tried since the message arrived. */
3321 debug_printf("all IP addresses skipped or deferred at least one address\n");
3322 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
3323 debug_printf("retrying IP addresses not tried since message arrived\n");
3328 /* Get here if all IP addresses are skipped or defer at least one address. In
3329 MUA wrapper mode, this will happen only for connection or other non-message-
3330 specific failures. Force the delivery status for all addresses to FAIL. */
3334 for (addr = addrlist; addr != NULL; addr = addr->next)
3335 addr->transport_return = FAIL;
3339 /* In the normal, non-wrapper case, add a standard message to each deferred
3340 address if there hasn't been an error, that is, if it hasn't actually been
3341 tried this time. The variable "expired" will be FALSE if any deliveries were
3342 actually tried, or if there was at least one host that was not expired. That
3343 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
3344 a delivery has been tried, an error code will be set, and the failing of the
3345 message is handled by the retry code later.
3347 If queue_smtp is set, or this transport was called to send a subsequent message
3348 down an existing TCP/IP connection, and something caused the host not to be
3349 found, we end up here, but can detect these cases and handle them specially. */
3351 for (addr = addrlist; addr != NULL; addr = addr->next)
3353 /* If host is not NULL, it means that we stopped processing the host list
3354 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
3355 means we need to behave as if some hosts were skipped because their retry
3356 time had not come. Specifically, this prevents the address from timing out.
3357 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
3358 hosts were tried. */
3362 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
3365 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
3366 "hosts were tried\n");
3371 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
3372 setflag(addr, af_retry_skipped);
3376 if (queue_smtp) /* no deliveries attempted */
3378 addr->transport_return = DEFER;
3379 addr->basic_errno = 0;
3380 addr->message = US"SMTP delivery explicitly queued";
3383 else if (addr->transport_return == DEFER &&
3384 (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0) &&
3385 addr->message == NULL)
3387 addr->basic_errno = ERRNO_HRETRY;
3388 if (continue_hostname != NULL)
3390 addr->message = US"no host found for existing SMTP connection";
3394 setflag(addr, af_pass_message); /* This is not a security risk */
3395 addr->message = (ob->delay_after_cutoff)?
3396 US"retry time not reached for any host after a long failure period" :
3397 US"all hosts have been failing for a long time and were last tried "
3398 "after this message arrived";
3400 /* If we are already using fallback hosts, or there are no fallback hosts
3401 defined, convert the result to FAIL to cause a bounce. */
3403 if (addr->host_list == addr->fallback_hosts ||
3404 addr->fallback_hosts == NULL)
3405 addr->transport_return = FAIL;
3409 if (hosts_retry == hosts_total)
3410 addr->message = US"retry time not reached for any host";
3411 else if (hosts_fail == hosts_total)
3412 addr->message = US"all host address lookups failed permanently";
3413 else if (hosts_defer == hosts_total)
3414 addr->message = US"all host address lookups failed temporarily";
3415 else if (hosts_serial == hosts_total)
3416 addr->message = US"connection limit reached for all hosts";
3417 else if (hosts_fail+hosts_defer == hosts_total)
3418 addr->message = US"all host address lookups failed";
3419 else addr->message = US"some host address lookups failed and retry time "
3420 "not reached for other hosts or connection limit reached";
3425 /* Update the database which keeps information about which messages are waiting
3426 for which hosts to become available. For some message-specific errors, the
3427 update_waiting flag is turned off because we don't want follow-on deliveries in
3428 those cases. If this transport instance is explicitly limited to one message
3429 per connection then follow-on deliveries are not possible and there's no need
3430 to create/update the per-transport wait-<transport_name> database. */
3432 if (update_waiting && tblock->connection_max_messages != 1)
3433 transport_update_waiting(hostlist, tblock->name);
3437 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3439 return TRUE; /* Each address has its status */
3444 /* End of transport/smtp.c */