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 { "dscp", opt_stringptr,
59 (void *)offsetof(smtp_transport_options_block, dscp) },
60 { "fallback_hosts", opt_stringptr,
61 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
62 { "final_timeout", opt_time,
63 (void *)offsetof(smtp_transport_options_block, final_timeout) },
64 { "gethostbyname", opt_bool,
65 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
67 /* These are no longer honoured, as of Exim 4.80; for now, we silently
68 ignore; a later release will warn, and a later-still release will remove
69 these options, so that using them becomes an error. */
70 { "gnutls_require_kx", opt_stringptr,
71 (void *)offsetof(smtp_transport_options_block, gnutls_require_kx) },
72 { "gnutls_require_mac", opt_stringptr,
73 (void *)offsetof(smtp_transport_options_block, gnutls_require_mac) },
74 { "gnutls_require_protocols", opt_stringptr,
75 (void *)offsetof(smtp_transport_options_block, gnutls_require_proto) },
77 { "helo_data", opt_stringptr,
78 (void *)offsetof(smtp_transport_options_block, helo_data) },
79 { "hosts", opt_stringptr,
80 (void *)offsetof(smtp_transport_options_block, hosts) },
81 { "hosts_avoid_esmtp", opt_stringptr,
82 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
83 { "hosts_avoid_pipelining", opt_stringptr,
84 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
86 { "hosts_avoid_tls", opt_stringptr,
87 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
89 { "hosts_max_try", opt_int,
90 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
91 { "hosts_max_try_hardlimit", opt_int,
92 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
94 { "hosts_nopass_tls", opt_stringptr,
95 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
97 { "hosts_override", opt_bool,
98 (void *)offsetof(smtp_transport_options_block, hosts_override) },
99 { "hosts_randomize", opt_bool,
100 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
101 { "hosts_require_auth", opt_stringptr,
102 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
104 # if defined EXPERIMENTAL_OCSP
105 { "hosts_require_ocsp", opt_stringptr,
106 (void *)offsetof(smtp_transport_options_block, hosts_require_ocsp) },
108 { "hosts_require_tls", opt_stringptr,
109 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
111 { "hosts_try_auth", opt_stringptr,
112 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
113 #ifdef EXPERIMENTAL_PRDR
114 { "hosts_try_prdr", opt_stringptr,
115 (void *)offsetof(smtp_transport_options_block, hosts_try_prdr) },
118 { "hosts_verify_avoid_tls", opt_stringptr,
119 (void *)offsetof(smtp_transport_options_block, hosts_verify_avoid_tls) },
121 { "interface", opt_stringptr,
122 (void *)offsetof(smtp_transport_options_block, interface) },
123 { "keepalive", opt_bool,
124 (void *)offsetof(smtp_transport_options_block, keepalive) },
125 { "lmtp_ignore_quota", opt_bool,
126 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
127 { "max_rcpt", opt_int | opt_public,
128 (void *)offsetof(transport_instance, max_addresses) },
129 { "multi_domain", opt_bool | opt_public,
130 (void *)offsetof(transport_instance, multi_domain) },
131 { "port", opt_stringptr,
132 (void *)offsetof(smtp_transport_options_block, port) },
133 { "protocol", opt_stringptr,
134 (void *)offsetof(smtp_transport_options_block, protocol) },
135 { "retry_include_ip_address", opt_bool,
136 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
137 { "serialize_hosts", opt_stringptr,
138 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
139 { "size_addition", opt_int,
140 (void *)offsetof(smtp_transport_options_block, size_addition) }
142 ,{ "tls_certificate", opt_stringptr,
143 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
144 { "tls_crl", opt_stringptr,
145 (void *)offsetof(smtp_transport_options_block, tls_crl) },
146 { "tls_dh_min_bits", opt_int,
147 (void *)offsetof(smtp_transport_options_block, tls_dh_min_bits) },
148 { "tls_privatekey", opt_stringptr,
149 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
150 { "tls_require_ciphers", opt_stringptr,
151 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
152 { "tls_sni", opt_stringptr,
153 (void *)offsetof(smtp_transport_options_block, tls_sni) },
154 { "tls_tempfail_tryclear", opt_bool,
155 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
156 { "tls_try_verify_hosts", opt_stringptr,
157 (void *)offsetof(smtp_transport_options_block, tls_try_verify_hosts) },
158 { "tls_verify_certificates", opt_stringptr,
159 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) },
160 { "tls_verify_hosts", opt_stringptr,
161 (void *)offsetof(smtp_transport_options_block, tls_verify_hosts) }
163 #ifdef EXPERIMENTAL_TPDA
164 ,{ "tpda_host_defer_action", opt_stringptr,
165 (void *)offsetof(smtp_transport_options_block, tpda_host_defer_action) },
169 /* Size of the options list. An extern variable has to be used so that its
170 address can appear in the tables drtables.c. */
172 int smtp_transport_options_count =
173 sizeof(smtp_transport_options)/sizeof(optionlist);
175 /* Default private options block for the smtp transport. */
177 smtp_transport_options_block smtp_transport_option_defaults = {
179 NULL, /* fallback_hosts */
181 NULL, /* fallback_hostlist */
182 NULL, /* authenticated_sender */
183 US"$primary_hostname", /* helo_data */
184 NULL, /* interface */
186 US"smtp", /* protocol */
188 NULL, /* serialize_hosts */
189 NULL, /* hosts_try_auth */
190 NULL, /* hosts_require_auth */
191 #ifdef EXPERIMENTAL_PRDR
192 NULL, /* hosts_try_prdr */
194 #ifdef EXPERIMENTAL_OCSP
195 NULL, /* hosts_require_ocsp */
197 NULL, /* hosts_require_tls */
198 NULL, /* hosts_avoid_tls */
199 US"*", /* hosts_verify_avoid_tls */
200 NULL, /* hosts_avoid_pipelining */
201 NULL, /* hosts_avoid_esmtp */
202 NULL, /* hosts_nopass_tls */
203 5*60, /* command_timeout */
204 5*60, /* connect_timeout; shorter system default overrides */
205 5*60, /* data timeout */
206 10*60, /* final timeout */
207 1024, /* size_addition */
208 5, /* hosts_max_try */
209 50, /* hosts_max_try_hardlimit */
210 TRUE, /* address_retry_include_sender */
211 FALSE, /* allow_localhost */
212 FALSE, /* authenticated_sender_force */
213 FALSE, /* gethostbyname */
214 TRUE, /* dns_qualify_single */
215 FALSE, /* dns_search_parents */
216 TRUE, /* delay_after_cutoff */
217 FALSE, /* hosts_override */
218 FALSE, /* hosts_randomize */
219 TRUE, /* keepalive */
220 FALSE, /* lmtp_ignore_quota */
221 TRUE /* retry_include_ip_address */
223 ,NULL, /* tls_certificate */
225 NULL, /* tls_privatekey */
226 NULL, /* tls_require_ciphers */
227 NULL, /* gnutls_require_kx */
228 NULL, /* gnutls_require_mac */
229 NULL, /* gnutls_require_proto */
231 NULL, /* tls_verify_certificates */
232 EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
233 /* tls_dh_min_bits */
234 TRUE, /* tls_tempfail_tryclear */
235 NULL, /* tls_verify_hosts */
236 NULL /* tls_try_verify_hosts */
239 ,NULL, /* dkim_canon */
240 NULL, /* dkim_domain */
241 NULL, /* dkim_private_key */
242 NULL, /* dkim_selector */
243 NULL, /* dkim_sign_headers */
244 NULL /* dkim_strict */
246 #ifdef EXPERIMENTAL_TPDA
247 ,NULL /* tpda_host_defer_action */
254 static uschar *smtp_command; /* Points to last cmd for error messages */
255 static uschar *mail_command; /* Points to MAIL cmd for error messages */
256 static BOOL update_waiting; /* TRUE to update the "wait" database */
259 /*************************************************
260 * Setup entry point *
261 *************************************************/
263 /* This function is called when the transport is about to be used,
264 but before running it in a sub-process. It is used for two things:
266 (1) To set the fallback host list in addresses, when delivering.
267 (2) To pass back the interface, port, protocol, and other options, for use
268 during callout verification.
271 tblock pointer to the transport instance block
272 addrlist list of addresses about to be transported
273 tf if not NULL, pointer to block in which to return options
274 uid the uid that will be set (not used)
275 gid the gid that will be set (not used)
276 errmsg place for error message (not used)
278 Returns: OK always (FAIL, DEFER not used)
282 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
283 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
285 smtp_transport_options_block *ob =
286 (smtp_transport_options_block *)(tblock->options_block);
288 errmsg = errmsg; /* Keep picky compilers happy */
292 /* Pass back options if required. This interface is getting very messy. */
296 tf->interface = ob->interface;
298 tf->protocol = ob->protocol;
299 tf->hosts = ob->hosts;
300 tf->hosts_override = ob->hosts_override;
301 tf->hosts_randomize = ob->hosts_randomize;
302 tf->gethostbyname = ob->gethostbyname;
303 tf->qualify_single = ob->dns_qualify_single;
304 tf->search_parents = ob->dns_search_parents;
305 tf->helo_data = ob->helo_data;
308 /* Set the fallback host list for all the addresses that don't have fallback
309 host lists, provided that the local host wasn't present in the original host
312 if (!testflag(addrlist, af_local_host_removed))
314 for (; addrlist != NULL; addrlist = addrlist->next)
315 if (addrlist->fallback_hosts == NULL)
316 addrlist->fallback_hosts = ob->fallback_hostlist;
324 /*************************************************
325 * Initialization entry point *
326 *************************************************/
328 /* Called for each instance, after its options have been read, to
329 enable consistency checks to be done, or anything else that needs
332 Argument: pointer to the transport instance block
337 smtp_transport_init(transport_instance *tblock)
339 smtp_transport_options_block *ob =
340 (smtp_transport_options_block *)(tblock->options_block);
342 /* Retry_use_local_part defaults FALSE if unset */
344 if (tblock->retry_use_local_part == TRUE_UNSET)
345 tblock->retry_use_local_part = FALSE;
347 /* Set the default port according to the protocol */
349 if (ob->port == NULL)
350 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
351 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
353 /* Set up the setup entry point, to be called before subprocesses for this
356 tblock->setup = smtp_transport_setup;
358 /* Complain if any of the timeouts are zero. */
360 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
361 ob->final_timeout <= 0)
362 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
363 "command, data, or final timeout value is zero for %s transport",
366 /* If hosts_override is set and there are local hosts, set the global
367 flag that stops verify from showing router hosts. */
369 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
371 /* If there are any fallback hosts listed, build a chain of host items
372 for them, but do not do any lookups at this time. */
374 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
381 /*************************************************
382 * Set delivery info into all active addresses *
383 *************************************************/
385 /* Only addresses whose status is >= PENDING are relevant. A lesser
386 status means that an address is not currently being processed.
389 addrlist points to a chain of addresses
390 errno_value to put in each address's errno field
391 msg to put in each address's message field
392 rc to put in each address's transport_return field
393 pass_message if TRUE, set the "pass message" flag in the address
395 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
396 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
397 this particular type of timeout.
403 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
408 if (errno_value == ERRNO_CONNECTTIMEOUT)
410 errno_value = ETIMEDOUT;
411 orvalue = RTEF_CTOUT;
413 for (addr = addrlist; addr != NULL; addr = addr->next)
415 if (addr->transport_return < PENDING) continue;
416 addr->basic_errno = errno_value;
417 addr->more_errno |= orvalue;
421 if (pass_message) setflag(addr, af_pass_message);
423 addr->transport_return = rc;
429 /*************************************************
430 * Check an SMTP response *
431 *************************************************/
433 /* This function is given an errno code and the SMTP response buffer
434 to analyse, together with the host identification for generating messages. It
435 sets an appropriate message and puts the first digit of the response code into
436 the yield variable. If no response was actually read, a suitable digit is
440 host the current host, to get its name for messages
441 errno_value pointer to the errno value
442 more_errno from the top address for use with ERRNO_FILTER_FAIL
443 buffer the SMTP response buffer
444 yield where to put a one-digit SMTP response code
445 message where to put an errror message
446 pass_message set TRUE if message is an SMTP response
448 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
451 static BOOL check_response(host_item *host, int *errno_value, int more_errno,
452 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
456 if (smtp_use_pipelining &&
457 (Ustrcmp(smtp_command, "MAIL") == 0 ||
458 Ustrcmp(smtp_command, "RCPT") == 0 ||
459 Ustrcmp(smtp_command, "DATA") == 0))
462 *yield = '4'; /* Default setting is to give a temporary error */
464 /* Handle response timeout */
466 if (*errno_value == ETIMEDOUT)
468 *message = US string_sprintf("SMTP timeout while connected to %s [%s] "
469 "after %s%s", host->name, host->address, pl, smtp_command);
470 if (transport_count > 0)
471 *message = US string_sprintf("%s (%d bytes written)", *message,
476 /* Handle malformed SMTP response */
478 if (*errno_value == ERRNO_SMTPFORMAT)
480 uschar *malfresp = string_printing(buffer);
481 while (isspace(*malfresp)) malfresp++;
483 *message = string_sprintf("Malformed SMTP reply (an empty line) from "
484 "%s [%s] in response to %s%s", host->name, host->address, pl,
487 *message = string_sprintf("Malformed SMTP reply from %s [%s] in response "
488 "to %s%s: %s", host->name, host->address, pl, smtp_command, malfresp);
492 /* Handle a failed filter process error; can't send QUIT as we mustn't
495 if (*errno_value == ERRNO_FILTER_FAIL)
497 *message = US string_sprintf("transport filter process failed (%d)%s",
499 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
503 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
506 if (*errno_value == ERRNO_CHHEADER_FAIL)
509 US string_sprintf("failed to expand headers_add or headers_remove: %s",
510 expand_string_message);
514 /* Handle failure to write a complete data block */
516 if (*errno_value == ERRNO_WRITEINCOMPLETE)
518 *message = US string_sprintf("failed to write a data block");
522 /* Handle error responses from the remote mailer. */
526 uschar *s = string_printing(buffer);
527 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
528 "host %s [%s]: %s", pl, smtp_command, host->name, host->address, s);
529 *pass_message = TRUE;
534 /* No data was read. If there is no errno, this must be the EOF (i.e.
535 connection closed) case, which causes deferral. An explicit connection reset
536 error has the same effect. Otherwise, put the host's identity in the message,
537 leaving the errno value to be interpreted as well. In all cases, we have to
538 assume the connection is now dead. */
540 if (*errno_value == 0 || *errno_value == ECONNRESET)
542 *errno_value = ERRNO_SMTPCLOSED;
543 *message = US string_sprintf("Remote host %s [%s] closed connection "
544 "in response to %s%s", host->name, host->address, pl, smtp_command);
546 else *message = US string_sprintf("%s [%s]", host->name, host->address);
553 /*************************************************
554 * Write error message to logs *
555 *************************************************/
557 /* This writes to the main log and to the message log.
560 addr the address item containing error information
561 host the current host
567 write_logs(address_item *addr, host_item *host)
569 if (addr->message != NULL)
571 uschar *message = addr->message;
572 if (addr->basic_errno > 0)
573 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
574 log_write(0, LOG_MAIN, "%s", message);
575 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
580 ((log_extra_selector & LX_outgoing_port) != 0)?
581 string_sprintf("%s [%s]:%d", host->name, host->address,
582 (host->port == PORT_NONE)? 25 : host->port)
584 string_sprintf("%s [%s]", host->name, host->address);
585 log_write(0, LOG_MAIN, "%s %s", msg, strerror(addr->basic_errno));
586 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), msg,
587 strerror(addr->basic_errno));
593 #ifdef EXPERIMENTAL_TPDA
594 /*************************************************
595 * Post-defer action *
596 *************************************************/
598 /* This expands an arbitrary per-transport string.
599 It might, for example, be used to write to the database log.
602 ob transport options block
603 addr the address item containing error information
604 host the current host
610 tpda_deferred(smtp_transport_options_block *ob, address_item *addr, host_item *host)
612 uschar *action = ob->tpda_host_defer_action;
616 tpda_delivery_ip = string_copy(host->address);
617 tpda_delivery_port = (host->port == PORT_NONE)? 25 : host->port;
618 tpda_delivery_fqdn = string_copy(host->name);
619 tpda_delivery_local_part = string_copy(addr->local_part);
620 tpda_delivery_domain = string_copy(addr->domain);
621 tpda_defer_errno = addr->basic_errno;
623 tpda_defer_errstr = addr->message
624 ? addr->basic_errno > 0
625 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
626 : string_copy(addr->message)
627 : addr->basic_errno > 0
628 ? string_copy(strerror(addr->basic_errno))
632 debug_printf(" TPDA(host defer): tpda_host_defer_action=|%s| tpda_delivery_IP=%s\n",
633 action, tpda_delivery_ip);
635 router_name = addr->router->name;
636 transport_name = addr->transport->name;
637 if (!expand_string(action) && *expand_string_message)
638 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand tpda_defer_action in %s: %s\n",
639 transport_name, expand_string_message);
640 router_name = transport_name = NULL;
646 /*************************************************
647 * Synchronize SMTP responses *
648 *************************************************/
650 /* This function is called from smtp_deliver() to receive SMTP responses from
651 the server, and match them up with the commands to which they relate. When
652 PIPELINING is not in use, this function is called after every command, and is
653 therefore somewhat over-engineered, but it is simpler to use a single scheme
654 that works both with and without PIPELINING instead of having two separate sets
657 The set of commands that are buffered up with pipelining may start with MAIL
658 and may end with DATA; in between are RCPT commands that correspond to the
659 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
660 etc.) are never buffered.
662 Errors after MAIL or DATA abort the whole process leaving the response in the
663 buffer. After MAIL, pending responses are flushed, and the original command is
664 re-instated in big_buffer for error messages. For RCPT commands, the remote is
665 permitted to reject some recipient addresses while accepting others. However
666 certain errors clearly abort the whole process. Set the value in
667 transport_return to PENDING_OK if the address is accepted. If there is a
668 subsequent general error, it will get reset accordingly. If not, it will get
669 converted to OK at the end.
672 addrlist the complete address list
673 include_affixes TRUE if affixes include in RCPT
674 sync_addr ptr to the ptr of the one to start scanning at (updated)
675 host the host we are connected to
676 count the number of responses to read
678 include_sender true if 4xx retry is to include the sender it its key
679 pending_MAIL true if the first response is for MAIL
680 pending_DATA 0 if last command sent was not DATA
681 +1 if previously had a good recipient
682 -1 if not previously had a good recipient
683 inblock incoming SMTP block
684 timeout timeout value
685 buffer buffer for reading response
686 buffsize size of buffer
688 Returns: 3 if at least one address had 2xx and one had 5xx
689 2 if at least one address had 5xx but none had 2xx
690 1 if at least one host had a 2xx response, but none had 5xx
691 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
692 -1 timeout while reading RCPT response
693 -2 I/O or other non-response error for RCPT
694 -3 DATA or MAIL failed - errno and buffer set
698 sync_responses(address_item *addrlist, BOOL include_affixes,
699 address_item **sync_addr, host_item *host, int count,
700 BOOL address_retry_include_sender, BOOL pending_MAIL,
701 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
704 address_item *addr = *sync_addr;
707 /* Handle the response for a MAIL command. On error, reinstate the original
708 command in big_buffer for error message use, and flush any further pending
709 responses before returning, except after I/O errors and timeouts. */
714 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
716 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
717 if (errno == 0 && buffer[0] != 0)
719 uschar flushbuffer[4096];
721 if (buffer[0] == '4')
723 save_errno = ERRNO_MAIL4XX;
724 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
728 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
730 && (errno != 0 || flushbuffer[0] == 0))
739 if (pending_DATA) count--; /* Number of RCPT responses to come */
741 /* Read and handle the required number of RCPT responses, matching each one up
742 with an address by scanning for the next address whose status is PENDING_DEFER.
747 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
749 /* The address was accepted */
751 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
754 addr->transport_return = PENDING_OK;
756 /* If af_dr_retry_exists is set, there was a routing delay on this address;
757 ensure that any address-specific retry record is expunged. We do this both
758 for the basic key and for the version that also includes the sender. */
760 if (testflag(addr, af_dr_retry_exists))
762 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
764 retry_add_item(addr, altkey, rf_delete);
765 retry_add_item(addr, addr->address_retry_key, rf_delete);
769 /* Timeout while reading the response */
771 else if (errno == ETIMEDOUT)
773 int save_errno = errno;
774 uschar *message = string_sprintf("SMTP timeout while connected to %s [%s] "
775 "after RCPT TO:<%s>", host->name, host->address,
776 transport_rcpt_address(addr, include_affixes));
777 set_errno(addrlist, save_errno, message, DEFER, FALSE);
778 retry_add_item(addr, addr->address_retry_key, 0);
779 update_waiting = FALSE;
783 /* Handle other errors in obtaining an SMTP response by returning -1. This
784 will cause all the addresses to be deferred. Restore the SMTP command in
785 big_buffer for which we are checking the response, so the error message
788 else if (errno != 0 || buffer[0] == 0)
790 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
791 transport_rcpt_address(addr, include_affixes));
795 /* Handle SMTP permanent and temporary response codes. */
800 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
801 "host %s [%s]: %s", transport_rcpt_address(addr, include_affixes),
802 host->name, host->address, string_printing(buffer));
803 setflag(addr, af_pass_message);
804 deliver_msglog("%s %s\n", tod_stamp(tod_log), addr->message);
806 /* The response was 5xx */
808 if (buffer[0] == '5')
810 addr->transport_return = FAIL;
814 /* The response was 4xx */
818 addr->transport_return = DEFER;
819 addr->basic_errno = ERRNO_RCPT4XX;
820 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
822 /* Log temporary errors if there are more hosts to be tried. */
824 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", addr->message);
826 /* Do not put this message on the list of those waiting for specific
827 hosts, as otherwise it is likely to be tried too often. */
829 update_waiting = FALSE;
831 /* Add a retry item for the address so that it doesn't get tried again
832 too soon. If address_retry_include_sender is true, add the sender address
835 if (address_retry_include_sender)
837 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
839 retry_add_item(addr, altkey, 0);
841 else retry_add_item(addr, addr->address_retry_key, 0);
844 } /* Loop for next RCPT response */
846 /* Update where to start at for the next block of responses, unless we
847 have already handled all the addresses. */
849 if (addr != NULL) *sync_addr = addr->next;
851 /* Handle a response to DATA. If we have not had any good recipients, either
852 previously or in this block, the response is ignored. */
854 if (pending_DATA != 0 &&
855 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
860 if (pending_DATA > 0 || (yield & 1) != 0)
862 if (errno == 0 && buffer[0] == '4')
864 errno = ERRNO_DATA4XX;
865 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
869 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
870 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
871 "is in use and there were no good recipients\n", msg);
874 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
875 present) received 3xx. If any RCPTs were handled and yielded anything other
876 than 4xx, yield will be set non-zero. */
883 /* Do the client side of smtp-level authentication */
886 buffer EHLO response from server (gets overwritten)
887 addrlist chain of potential addresses to deliver
888 host host to deliver to
890 ibp, obp comms channel control blocks
893 OK Success, or failed (but not required): global "smtp_authenticated" set
894 DEFER Failed authentication (and was required)
895 ERROR Internal problem
897 FAIL_SEND Failed communications - transmit
902 smtp_auth(uschar *buffer, unsigned bufsize, address_item *addrlist, host_item *host,
903 smtp_transport_options_block *ob, BOOL is_esmtp,
904 smtp_inblock *ibp, smtp_outblock *obp)
907 uschar *fail_reason = US"server did not advertise AUTH support";
909 smtp_authenticated = FALSE;
910 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
911 require_auth = verify_check_this_host(&(ob->hosts_require_auth), NULL,
912 host->name, host->address, NULL);
914 if (is_esmtp && !regex_AUTH) regex_AUTH =
915 regex_must_compile(US"\\n250[\\s\\-]AUTH\\s+([\\-\\w\\s]+)(?:\\n|$)",
918 if (is_esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
920 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
921 expand_nmax = -1; /* reset */
923 /* Must not do this check until after we have saved the result of the
924 regex match above. */
926 if (require_auth == OK ||
927 verify_check_this_host(&(ob->hosts_try_auth), NULL, host->name,
928 host->address, NULL) == OK)
931 fail_reason = US"no common mechanisms were found";
933 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
935 /* Scan the configured authenticators looking for one which is configured
936 for use as a client, which is not suppressed by client_condition, and
937 whose name matches an authentication mechanism supported by the server.
938 If one is found, attempt to authenticate by calling its client function.
941 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
945 (au->client_condition != NULL &&
946 !expand_check_condition(au->client_condition, au->name,
947 US"client authenticator")))
949 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
951 (au->client)? "client_condition is false" :
952 "not configured as a client");
956 /* Loop to scan supported server mechanisms */
961 int len = Ustrlen(au->public_name);
962 while (isspace(*p)) p++;
964 if (strncmpic(au->public_name, p, len) != 0 ||
965 (p[len] != 0 && !isspace(p[len])))
967 while (*p != 0 && !isspace(*p)) p++;
971 /* Found data for a listed mechanism. Call its client entry. Set
972 a flag in the outblock so that data is overwritten after sending so
973 that reflections don't show it. */
975 fail_reason = US"authentication attempt(s) failed";
976 obp->authenticating = TRUE;
977 rc = (au->info->clientcode)(au, ibp, obp,
978 ob->command_timeout, buffer, bufsize);
979 obp->authenticating = FALSE;
980 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
983 /* A temporary authentication failure must hold up delivery to
984 this host. After a permanent authentication failure, we carry on
985 to try other authentication methods. If all fail hard, try to
986 deliver the message unauthenticated unless require_auth was set. */
991 smtp_authenticated = TRUE; /* stops the outer loop */
992 client_authenticator = au->name;
993 if (au->set_client_id != NULL)
994 client_authenticated_id = expand_string(au->set_client_id);
997 /* Failure after writing a command */
1002 /* Failure after reading a response */
1005 if (errno != 0 || buffer[0] != '5') return FAIL;
1006 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1007 au->name, host->name, host->address, buffer);
1010 /* Failure by some other means. In effect, the authenticator
1011 decided it wasn't prepared to handle this case. Typically this
1012 is the result of "fail" in an expansion string. Do we need to
1013 log anything here? Feb 2006: a message is now put in the buffer
1014 if logging is required. */
1018 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1019 "authentication H=%s [%s] %s", au->name, host->name,
1020 host->address, buffer);
1023 /* Internal problem, message in buffer. */
1026 set_errno(addrlist, 0, string_copy(buffer), DEFER, FALSE);
1030 break; /* If not authenticated, try next authenticator */
1031 } /* Loop for scanning supported server mechanisms */
1032 } /* Loop for further authenticators */
1036 /* If we haven't authenticated, but are required to, give up. */
1038 if (require_auth == OK && !smtp_authenticated)
1040 set_errno(addrlist, ERRNO_AUTHFAIL,
1041 string_sprintf("authentication required but %s", fail_reason), DEFER,
1050 /* Construct AUTH appendix string for MAIL TO */
1053 buffer to build string
1054 addrlist chain of potential addresses to deliver
1055 ob transport options
1057 Globals smtp_authenticated
1058 client_authenticated_sender
1059 Return True on error, otherwise buffer has (possibly empty) terminated string
1063 smtp_mail_auth_str(uschar *buffer, unsigned bufsize, address_item *addrlist,
1064 smtp_transport_options_block *ob)
1066 uschar *local_authenticated_sender = authenticated_sender;
1069 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n", authenticated_sender, ob->authenticated_sender, smtp_authenticated?"Y":"N");
1072 if (ob->authenticated_sender != NULL)
1074 uschar *new = expand_string(ob->authenticated_sender);
1077 if (!expand_string_forcedfail)
1079 uschar *message = string_sprintf("failed to expand "
1080 "authenticated_sender: %s", expand_string_message);
1081 set_errno(addrlist, 0, message, DEFER, FALSE);
1085 else if (new[0] != 0) local_authenticated_sender = new;
1088 /* Add the authenticated sender address if present */
1090 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1091 local_authenticated_sender != NULL)
1093 string_format(buffer, bufsize, " AUTH=%s",
1094 auth_xtextencode(local_authenticated_sender,
1095 Ustrlen(local_authenticated_sender)));
1096 client_authenticated_sender = string_copy(local_authenticated_sender);
1106 /*************************************************
1107 * Deliver address list to given host *
1108 *************************************************/
1110 /* If continue_hostname is not null, we get here only when continuing to
1111 deliver down an existing channel. The channel was passed as the standard
1112 input. TLS is never active on a passed channel; the previous process always
1113 closes it down before passing the connection on.
1115 Otherwise, we have to make a connection to the remote host, and do the
1116 initial protocol exchange.
1118 When running as an MUA wrapper, if the sender or any recipient is rejected,
1119 temporarily or permanently, we force failure for all recipients.
1122 addrlist chain of potential addresses to deliver; only those whose
1123 transport_return field is set to PENDING_DEFER are currently
1124 being processed; others should be skipped - they have either
1125 been delivered to an earlier host or IP address, or been
1126 failed by one of them.
1127 host host to deliver to
1128 host_af AF_INET or AF_INET6
1129 port default TCP/IP port to use, in host byte order
1130 interface interface to bind to, or NULL
1131 tblock transport instance block
1132 copy_host TRUE if host set in addr->host_used must be copied, because
1133 it is specific to this call of the transport
1134 message_defer set TRUE if yield is OK, but all addresses were deferred
1135 because of a non-recipient, non-host failure, that is, a
1136 4xx response to MAIL FROM, DATA, or ".". This is a defer
1137 that is specific to the message.
1138 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1139 a second attempt after TLS initialization fails
1141 Returns: OK - the connection was made and the delivery attempted;
1142 the result for each address is in its data block.
1143 DEFER - the connection could not be made, or something failed
1144 while setting up the SMTP session, or there was a
1145 non-message-specific error, such as a timeout.
1146 ERROR - a filter command is specified for this transport,
1147 and there was a problem setting it up; OR helo_data
1148 or add_headers or authenticated_sender is specified
1149 for this transport, and the string failed to expand
1153 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
1154 uschar *interface, transport_instance *tblock, BOOL copy_host,
1155 BOOL *message_defer, BOOL suppress_tls)
1158 address_item *sync_addr;
1159 address_item *first_addr = addrlist;
1164 time_t start_delivery_time = time(NULL);
1165 smtp_transport_options_block *ob =
1166 (smtp_transport_options_block *)(tblock->options_block);
1167 BOOL lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
1168 BOOL smtps = strcmpic(ob->protocol, US"smtps") == 0;
1170 BOOL send_rset = TRUE;
1171 BOOL send_quit = TRUE;
1172 BOOL setting_up = TRUE;
1173 BOOL completed_address = FALSE;
1176 BOOL pass_message = FALSE;
1177 #ifdef EXPERIMENTAL_PRDR
1178 BOOL prdr_offered = FALSE;
1181 smtp_inblock inblock;
1182 smtp_outblock outblock;
1183 int max_rcpt = tblock->max_addresses;
1184 uschar *igquotstr = US"";
1185 uschar *helo_data = NULL;
1186 uschar *message = NULL;
1187 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
1189 uschar buffer[4096];
1190 uschar inbuffer[4096];
1191 uschar outbuffer[1024];
1193 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
1195 *message_defer = FALSE;
1196 smtp_command = US"initial connection";
1197 if (max_rcpt == 0) max_rcpt = 999999;
1199 /* Set up the buffer for reading SMTP response packets. */
1201 inblock.buffer = inbuffer;
1202 inblock.buffersize = sizeof(inbuffer);
1203 inblock.ptr = inbuffer;
1204 inblock.ptrend = inbuffer;
1206 /* Set up the buffer for holding SMTP commands while pipelining */
1208 outblock.buffer = outbuffer;
1209 outblock.buffersize = sizeof(outbuffer);
1210 outblock.ptr = outbuffer;
1211 outblock.cmd_count = 0;
1212 outblock.authenticating = FALSE;
1214 /* Reset the parameters of a TLS session. */
1217 tls_out.cipher = NULL; /* the one we may use for this transport */
1218 tls_out.peerdn = NULL;
1219 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1223 /* Flip the legacy TLS-related variables over to the outbound set in case
1224 they're used in the context of the transport. Don't bother resetting
1225 afterward as we're in a subprocess. */
1227 tls_modify_variables(&tls_out);
1232 set_errno(addrlist, 0, US"TLS support not available", DEFER, FALSE);
1237 /* Make a connection to the host if this isn't a continued delivery, and handle
1238 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
1239 specially so they can be identified for retries. */
1241 if (continue_hostname == NULL)
1243 inblock.sock = outblock.sock =
1244 smtp_connect(host, host_af, port, interface, ob->connect_timeout,
1245 ob->keepalive, ob->dscp); /* This puts port into host->port */
1247 if (inblock.sock < 0)
1249 set_errno(addrlist, (errno == ETIMEDOUT)? ERRNO_CONNECTTIMEOUT : errno,
1250 NULL, DEFER, FALSE);
1254 /* Expand the greeting message while waiting for the initial response. (Makes
1255 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1256 delayed till here so that $sending_interface and $sending_port are set. */
1258 helo_data = expand_string(ob->helo_data);
1260 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1261 is nevertheless a reasonably clean way of programming this kind of logic,
1262 where you want to escape on any error. */
1266 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1267 ob->command_timeout)) goto RESPONSE_FAILED;
1269 /* Now check if the helo_data expansion went well, and sign off cleanly if
1272 if (helo_data == NULL)
1274 uschar *message = string_sprintf("failed to expand helo_data: %s",
1275 expand_string_message);
1276 set_errno(addrlist, 0, message, DEFER, FALSE);
1282 /** Debugging without sending a message
1283 addrlist->transport_return = DEFER;
1287 /* Errors that occur after this point follow an SMTP command, which is
1288 left in big_buffer by smtp_write_command() for use in error messages. */
1290 smtp_command = big_buffer;
1292 /* Tell the remote who we are...
1294 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1295 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1296 greeting is of this form. The assumption was that the far end supports it
1297 properly... but experience shows that there are some that give 5xx responses,
1298 even though the banner includes "ESMTP" (there's a bloody-minded one that
1299 says "ESMTP not spoken here"). Cope with that case.
1301 September 2000: Time has passed, and it seems reasonable now to always send
1302 EHLO at the start. It is also convenient to make the change while installing
1305 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1306 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1307 would be no way to send out the mails, so there is now a host list
1308 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1309 PIPELINING problem as well. Maybe it can also be useful to cure other
1310 problems with broken servers.
1312 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1313 Then somebody tried it with a Microsoft mailer... It seems that all other
1314 mailers use upper case for some reason (the RFC is quite clear about case
1315 independence) so, for peace of mind, I gave in. */
1317 esmtp = verify_check_this_host(&(ob->hosts_avoid_esmtp), NULL,
1318 host->name, host->address, NULL) != OK;
1320 /* Alas; be careful, since this goto is not an error-out, so conceivably
1321 we might set data between here and the target which we assume to exist
1322 and be usable. I can see this coming back to bite us. */
1327 suppress_tls = FALSE;
1328 ob->tls_tempfail_tryclear = FALSE;
1329 smtp_command = US"SSL-on-connect";
1336 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1337 lmtp? "LHLO" : "EHLO", helo_data) < 0)
1339 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1340 ob->command_timeout))
1342 if (errno != 0 || buffer[0] == 0 || lmtp) goto RESPONSE_FAILED;
1349 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1354 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1356 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1357 ob->command_timeout)) goto RESPONSE_FAILED;
1360 /* Set IGNOREQUOTA if the response to LHLO specifies support and the
1361 lmtp_ignore_quota option was set. */
1363 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1364 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1365 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1367 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1370 tls_offered = esmtp &&
1371 pcre_exec(regex_STARTTLS, NULL, CS buffer, Ustrlen(buffer), 0,
1372 PCRE_EOPT, NULL, 0) >= 0;
1375 #ifdef EXPERIMENTAL_PRDR
1376 prdr_offered = esmtp &&
1377 (pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(buffer), 0,
1378 PCRE_EOPT, NULL, 0) >= 0) &&
1379 (verify_check_this_host(&(ob->hosts_try_prdr), NULL, host->name,
1380 host->address, NULL) == OK);
1383 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1387 /* For continuing deliveries down the same channel, the socket is the standard
1388 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1389 below). Set up the pointer to where subsequent commands will be left, for
1390 error messages. Note that smtp_use_size and smtp_use_pipelining will have been
1391 set from the command line if they were set in the process that passed the
1396 inblock.sock = outblock.sock = fileno(stdin);
1397 smtp_command = big_buffer;
1398 host->port = port; /* Record the port that was used */
1401 /* If TLS is available on this connection, whether continued or not, attempt to
1402 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1403 send another EHLO - the server may give a different answer in secure mode. We
1404 use a separate buffer for reading the response to STARTTLS so that if it is
1405 negative, the original EHLO data is available for subsequent analysis, should
1406 the client not be required to use TLS. If the response is bad, copy the buffer
1407 for error analysis. */
1410 if (tls_offered && !suppress_tls &&
1411 verify_check_this_host(&(ob->hosts_avoid_tls), NULL, host->name,
1412 host->address, NULL) != OK)
1414 uschar buffer2[4096];
1415 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1418 /* If there is an I/O error, transmission of this message is deferred. If
1419 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1420 false, we also defer. However, if there is a temporary rejection of STARTTLS
1421 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1422 STARTTLS, we carry on. This means we will try to send the message in clear,
1423 unless the host is in hosts_require_tls (tested below). */
1425 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1426 ob->command_timeout))
1428 if (errno != 0 || buffer2[0] == 0 ||
1429 (buffer2[0] == '4' && !ob->tls_tempfail_tryclear))
1431 Ustrncpy(buffer, buffer2, sizeof(buffer));
1432 goto RESPONSE_FAILED;
1436 /* STARTTLS accepted: try to negotiate a TLS session. */
1441 int rc = tls_client_start(inblock.sock,
1444 ob->tls_certificate,
1447 ob->tls_verify_certificates,
1449 ob->tls_require_ciphers,
1450 #ifdef EXPERIMENTAL_OCSP
1451 ob->hosts_require_ocsp,
1453 ob->tls_dh_min_bits,
1454 ob->command_timeout,
1455 ob->tls_verify_hosts,
1456 ob->tls_try_verify_hosts);
1458 /* TLS negotiation failed; give an error. From outside, this function may
1459 be called again to try in clear on a new connection, if the options permit
1460 it for this host. */
1464 save_errno = ERRNO_TLSFAILURE;
1465 message = US"failure while setting up TLS session";
1470 /* TLS session is set up */
1472 for (addr = addrlist; addr != NULL; addr = addr->next)
1474 if (addr->transport_return == PENDING_DEFER)
1476 addr->cipher = tls_out.cipher;
1477 addr->peerdn = tls_out.peerdn;
1483 /* if smtps, we'll have smtp_command set to something else; always safe to
1485 smtp_command = big_buffer;
1487 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1488 helo_data is null, we are dealing with a connection that was passed from
1489 another process, and so we won't have expanded helo_data above. We have to
1490 expand it here. $sending_ip_address and $sending_port are set up right at the
1491 start of the Exim process (in exim.c). */
1493 if (tls_out.active >= 0)
1496 if (helo_data == NULL)
1498 helo_data = expand_string(ob->helo_data);
1499 if (helo_data == NULL)
1501 uschar *message = string_sprintf("failed to expand helo_data: %s",
1502 expand_string_message);
1503 set_errno(addrlist, 0, message, DEFER, FALSE);
1509 /* For SMTPS we need to wait for the initial OK response. */
1512 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1513 ob->command_timeout)) goto RESPONSE_FAILED;
1517 greeting_cmd = "EHLO";
1520 greeting_cmd = "HELO";
1522 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1525 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1526 lmtp? "LHLO" : greeting_cmd, helo_data) < 0)
1528 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1529 ob->command_timeout))
1530 goto RESPONSE_FAILED;
1533 /* If the host is required to use a secure channel, ensure that we
1536 else if (verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
1537 host->address, NULL) == OK)
1539 save_errno = ERRNO_TLSREQUIRED;
1540 message = string_sprintf("a TLS session is required for %s [%s], but %s",
1541 host->name, host->address,
1542 tls_offered? "an attempt to start TLS failed" :
1543 "the server did not offer TLS support");
1548 /* If TLS is active, we have just started it up and re-done the EHLO command,
1549 so its response needs to be analyzed. If TLS is not active and this is a
1550 continued session down a previously-used socket, we haven't just done EHLO, so
1553 if (continue_hostname == NULL
1555 || tls_out.active >= 0
1559 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
1560 lmtp_ignore_quota option was set. */
1562 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1563 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1564 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1566 /* If the response to EHLO specified support for the SIZE parameter, note
1567 this, provided size_addition is non-negative. */
1569 smtp_use_size = esmtp && ob->size_addition >= 0 &&
1570 pcre_exec(regex_SIZE, NULL, CS buffer, Ustrlen(CS buffer), 0,
1571 PCRE_EOPT, NULL, 0) >= 0;
1573 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
1574 the current host, esmtp will be false, so PIPELINING can never be used. If
1575 the current host matches hosts_avoid_pipelining, don't do it. */
1577 smtp_use_pipelining = esmtp &&
1578 verify_check_this_host(&(ob->hosts_avoid_pipelining), NULL, host->name,
1579 host->address, NULL) != OK &&
1580 pcre_exec(regex_PIPELINING, NULL, CS buffer, Ustrlen(CS buffer), 0,
1581 PCRE_EOPT, NULL, 0) >= 0;
1583 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
1584 smtp_use_pipelining? "" : "not ");
1586 #ifdef EXPERIMENTAL_PRDR
1587 prdr_offered = esmtp &&
1588 pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(CS buffer), 0,
1589 PCRE_EOPT, NULL, 0) >= 0 &&
1590 verify_check_this_host(&(ob->hosts_try_prdr), NULL, host->name,
1591 host->address, NULL) == OK;
1594 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1597 /* Note if the response to EHLO specifies support for the AUTH extension.
1598 If it has, check that this host is one we want to authenticate to, and do
1599 the business. The host name and address must be available when the
1600 authenticator's client driver is running. */
1602 switch (yield = smtp_auth(buffer, sizeof(buffer), addrlist, host,
1603 ob, esmtp, &inblock, &outblock))
1605 default: goto SEND_QUIT;
1607 case FAIL_SEND: goto SEND_FAILED;
1608 case FAIL: goto RESPONSE_FAILED;
1612 /* The setting up of the SMTP call is now complete. Any subsequent errors are
1613 message-specific. */
1617 /* If there is a filter command specified for this transport, we can now
1618 set it up. This cannot be done until the identify of the host is known. */
1620 if (tblock->filter_command != NULL)
1624 sprintf(CS buffer, "%.50s transport", tblock->name);
1625 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
1626 TRUE, DEFER, addrlist, buffer, NULL);
1627 transport_filter_timeout = tblock->filter_timeout;
1629 /* On failure, copy the error to all addresses, abandon the SMTP call, and
1634 set_errno(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
1642 /* For messages that have more than the maximum number of envelope recipients,
1643 we want to send several transactions down the same SMTP connection. (See
1644 comments in deliver.c as to how this reconciles, heuristically, with
1645 remote_max_parallel.) This optimization was added to Exim after the following
1646 code was already working. The simplest way to put it in without disturbing the
1647 code was to use a goto to jump back to this point when there is another
1648 transaction to handle. */
1651 sync_addr = first_addr;
1655 completed_address = FALSE;
1658 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
1659 qualification, send it, adding something to the message size to allow for
1660 imprecision and things that get added en route. Exim keeps the number of lines
1661 in a message, so we can give an accurate value for the original message, but we
1662 need some additional to handle added headers. (Double "." characters don't get
1663 included in the count.) */
1670 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
1674 #ifdef EXPERIMENTAL_PRDR
1675 prdr_active = FALSE;
1678 for (addr = first_addr; addr; addr = addr->next)
1679 if (addr->transport_return == PENDING_DEFER)
1681 for (addr = addr->next; addr; addr = addr->next)
1682 if (addr->transport_return == PENDING_DEFER)
1683 { /* at least two recipients to send */
1685 sprintf(CS p, " PRDR"); p += 5;
1686 goto prdr_is_active;
1694 /* If an authenticated_sender override has been specified for this transport
1695 instance, expand it. If the expansion is forced to fail, and there was already
1696 an authenticated_sender for this message, the original value will be used.
1697 Other expansion failures are serious. An empty result is ignored, but there is
1698 otherwise no check - this feature is expected to be used with LMTP and other
1699 cases where non-standard addresses (e.g. without domains) might be required. */
1701 if (smtp_mail_auth_str(p, sizeof(buffer) - (p-buffer), addrlist, ob))
1704 /* From here until we send the DATA command, we can make use of PIPELINING
1705 if the server host supports it. The code has to be able to check the responses
1706 at any point, for when the buffer fills up, so we write it totally generally.
1707 When PIPELINING is off, each command written reports that it has flushed the
1710 pending_MAIL = TRUE; /* The block starts with MAIL */
1712 rc = smtp_write_command(&outblock, smtp_use_pipelining,
1713 "MAIL FROM:<%s>%s\r\n", return_path, buffer);
1714 mail_command = string_copy(big_buffer); /* Save for later error message */
1718 case -1: /* Transmission error */
1721 case +1: /* Block was sent */
1722 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1723 ob->command_timeout))
1725 if (errno == 0 && buffer[0] == '4')
1727 errno = ERRNO_MAIL4XX;
1728 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1730 goto RESPONSE_FAILED;
1732 pending_MAIL = FALSE;
1736 /* Pass over all the relevant recipient addresses for this host, which are the
1737 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
1738 several before we have to read the responses for those seen so far. This
1739 checking is done by a subroutine because it also needs to be done at the end.
1740 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
1741 the next one if not all are sent.
1743 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
1744 last address because we want to abort if any recipients have any kind of
1745 problem, temporary or permanent. We know that all recipient addresses will have
1746 the PENDING_DEFER status, because only one attempt is ever made, and we know
1747 that max_rcpt will be large, so all addresses will be done at once. */
1749 for (addr = first_addr;
1750 address_count < max_rcpt && addr != NULL;
1756 if (addr->transport_return != PENDING_DEFER) continue;
1759 no_flush = smtp_use_pipelining && (!mua_wrapper || addr->next != NULL);
1761 /* Now send the RCPT command, and process outstanding responses when
1762 necessary. After a timeout on RCPT, we just end the function, leaving the
1763 yield as OK, because this error can often mean that there is a problem with
1764 just one address, so we don't want to delay the host. */
1766 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s\r\n",
1767 transport_rcpt_address(addr, tblock->rcpt_include_affixes), igquotstr);
1768 if (count < 0) goto SEND_FAILED;
1771 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
1772 &sync_addr, host, count, ob->address_retry_include_sender,
1773 pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
1776 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1777 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1780 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1781 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1782 case 0: /* No 2xx or 5xx, but no probs */
1785 case -1: goto END_OFF; /* Timeout on RCPT */
1786 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
1788 pending_MAIL = FALSE; /* Dealt with MAIL */
1790 } /* Loop for next address */
1792 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
1793 permanently or temporarily. We should have flushed and synced after the last
1798 address_item *badaddr;
1799 for (badaddr = first_addr; badaddr != NULL; badaddr = badaddr->next)
1801 if (badaddr->transport_return != PENDING_OK) break;
1803 if (badaddr != NULL)
1805 set_errno(addrlist, 0, badaddr->message, FAIL,
1806 testflag(badaddr, af_pass_message));
1811 /* If ok is TRUE, we know we have got at least one good recipient, and must now
1812 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
1813 have a good recipient buffered up if we are pipelining. We don't want to waste
1814 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
1815 are pipelining. The responses are all handled by sync_responses(). */
1817 if (ok || (smtp_use_pipelining && !mua_wrapper))
1819 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
1820 if (count < 0) goto SEND_FAILED;
1821 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
1822 host, count, ob->address_retry_include_sender, pending_MAIL,
1823 ok? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
1825 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1826 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1829 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1830 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1831 case 0: break; /* No 2xx or 5xx, but no probs */
1833 case -1: goto END_OFF; /* Timeout on RCPT */
1834 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
1838 /* Save the first address of the next batch. */
1842 /* If there were no good recipients (but otherwise there have been no
1843 problems), just set ok TRUE, since we have handled address-specific errors
1844 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
1845 for handling the SMTP dot-handling protocol, flagging to apply to headers as
1846 well as body. Set the appropriate timeout value to be used for each chunk.
1847 (Haven't been able to make it work using select() for writing yet.) */
1849 if (!ok) ok = TRUE; else
1851 sigalrm_seen = FALSE;
1852 transport_write_timeout = ob->data_timeout;
1853 smtp_command = US"sending data block"; /* For error messages */
1854 DEBUG(D_transport|D_v)
1855 debug_printf(" SMTP>> writing message and terminating \".\"\n");
1856 transport_count = 0;
1857 #ifndef DISABLE_DKIM
1858 ok = dkim_transport_write_message(addrlist, inblock.sock,
1859 topt_use_crlf | topt_end_dot | topt_escape_headers |
1860 (tblock->body_only? topt_no_headers : 0) |
1861 (tblock->headers_only? topt_no_body : 0) |
1862 (tblock->return_path_add? topt_add_return_path : 0) |
1863 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1864 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1865 0, /* No size limit */
1866 tblock->add_headers, tblock->remove_headers,
1867 US".", US"..", /* Escaping strings */
1868 tblock->rewrite_rules, tblock->rewrite_existflags,
1869 ob->dkim_private_key, ob->dkim_domain, ob->dkim_selector,
1870 ob->dkim_canon, ob->dkim_strict, ob->dkim_sign_headers
1873 ok = transport_write_message(addrlist, inblock.sock,
1874 topt_use_crlf | topt_end_dot | topt_escape_headers |
1875 (tblock->body_only? topt_no_headers : 0) |
1876 (tblock->headers_only? topt_no_body : 0) |
1877 (tblock->return_path_add? topt_add_return_path : 0) |
1878 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1879 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1880 0, /* No size limit */
1881 tblock->add_headers, tblock->remove_headers,
1882 US".", US"..", /* Escaping strings */
1883 tblock->rewrite_rules, tblock->rewrite_existflags);
1886 /* transport_write_message() uses write() because it is called from other
1887 places to write to non-sockets. This means that under some OS (e.g. Solaris)
1888 it can exit with "Broken pipe" as its error. This really means that the
1889 socket got closed at the far end. */
1891 transport_write_timeout = 0; /* for subsequent transports */
1893 /* Failure can either be some kind of I/O disaster (including timeout),
1894 or the failure of a transport filter or the expansion of added headers. */
1898 buffer[0] = 0; /* There hasn't been a response */
1899 goto RESPONSE_FAILED;
1902 /* We used to send the terminating "." explicitly here, but because of
1903 buffering effects at both ends of TCP/IP connections, you don't gain
1904 anything by keeping it separate, so it might as well go in the final
1905 data buffer for efficiency. This is now done by setting the topt_end_dot
1908 smtp_command = US"end of data";
1910 #ifdef EXPERIMENTAL_PRDR
1911 /* For PRDR we optionally get a partial-responses warning
1912 * followed by the individual responses, before going on with
1913 * the overall response. If we don't get the warning then deal
1914 * with per non-PRDR. */
1917 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '3',
1919 if (!ok && errno == 0)
1922 case '2': prdr_active = FALSE;
1925 case '4': errno = ERRNO_DATA4XX;
1926 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1933 /* For non-PRDR SMTP, we now read a single response that applies to the
1934 whole message. If it is OK, then all the addresses have been delivered. */
1938 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1940 if (!ok && errno == 0 && buffer[0] == '4')
1942 errno = ERRNO_DATA4XX;
1943 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1947 /* For LMTP, we get back a response for every RCPT command that we sent;
1948 some may be accepted and some rejected. For those that get a response, their
1949 status is fixed; any that are accepted have been handed over, even if later
1950 responses crash - at least, that's how I read RFC 2033.
1952 If all went well, mark the recipient addresses as completed, record which
1953 host/IPaddress they were delivered to, and cut out RSET when sending another
1954 message down the same channel. Write the completed addresses to the journal
1955 now so that they are recorded in case there is a crash of hardware or
1956 software before the spool gets updated. Also record the final SMTP
1957 confirmation if needed (for SMTP only). */
1962 int delivery_time = (int)(time(NULL) - start_delivery_time);
1965 uschar *conf = NULL;
1968 /* Make a copy of the host if it is local to this invocation
1969 of the transport. */
1973 thost = store_get(sizeof(host_item));
1975 thost->name = string_copy(host->name);
1976 thost->address = string_copy(host->address);
1980 /* Set up confirmation if needed - applies only to SMTP */
1983 #ifndef EXPERIMENTAL_TPDA
1984 (log_extra_selector & LX_smtp_confirmation) != 0 &&
1989 uschar *s = string_printing(buffer);
1990 conf = (s == buffer)? (uschar *)string_copy(s) : s;
1993 /* Process all transported addresses - for LMTP or PRDR, read a status for
1996 for (addr = addrlist; addr != first_addr; addr = addr->next)
1998 if (addr->transport_return != PENDING_OK) continue;
2000 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
2001 remaining addresses. Otherwise, it's a return code for just the one
2002 address. For temporary errors, add a retry item for the address so that
2003 it doesn't get tried again too soon. */
2005 #ifdef EXPERIMENTAL_PRDR
2006 if (lmtp || prdr_active)
2011 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2014 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
2015 addr->message = string_sprintf(
2016 #ifdef EXPERIMENTAL_PRDR
2017 "%s error after %s: %s", prdr_active ? "PRDR":"LMTP",
2019 "LMTP error after %s: %s",
2021 big_buffer, string_printing(buffer));
2022 setflag(addr, af_pass_message); /* Allow message to go to user */
2023 if (buffer[0] == '5')
2024 addr->transport_return = FAIL;
2027 errno = ERRNO_DATA4XX;
2028 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2029 addr->transport_return = DEFER;
2030 #ifdef EXPERIMENTAL_PRDR
2033 retry_add_item(addr, addr->address_retry_key, 0);
2037 completed_address = TRUE; /* NOW we can set this flag */
2038 if ((log_extra_selector & LX_smtp_confirmation) != 0)
2040 uschar *s = string_printing(buffer);
2041 conf = (s == buffer)? (uschar *)string_copy(s) : s;
2045 /* SMTP, or success return from LMTP for this address. Pass back the
2046 actual host that was used. */
2048 addr->transport_return = OK;
2049 addr->more_errno = delivery_time;
2050 addr->host_used = thost;
2051 addr->special_action = flag;
2052 addr->message = conf;
2053 #ifdef EXPERIMENTAL_PRDR
2054 if (prdr_active) addr->flags |= af_prdr_used;
2058 #ifdef EXPERIMENTAL_PRDR
2062 /* Update the journal. For homonymic addresses, use the base address plus
2063 the transport name. See lots of comments in deliver.c about the reasons
2064 for the complications when homonyms are involved. Just carry on after
2065 write error, as it may prove possible to update the spool file later. */
2067 if (testflag(addr, af_homonym))
2068 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2070 sprintf(CS buffer, "%.500s\n", addr->unique);
2072 DEBUG(D_deliver) debug_printf("journalling %s", buffer);
2073 len = Ustrlen(CS buffer);
2074 if (write(journal_fd, buffer, len) != len)
2075 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2076 "%s: %s", buffer, strerror(errno));
2080 #ifdef EXPERIMENTAL_PRDR
2083 /* PRDR - get the final, overall response. For any non-success
2084 upgrade all the address statuses. */
2085 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2089 if(errno == 0 && buffer[0] == '4')
2091 errno = ERRNO_DATA4XX;
2092 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2094 for (addr = addrlist; addr != first_addr; addr = addr->next)
2095 if (buffer[0] == '5' || addr->transport_return == OK)
2096 addr->transport_return = PENDING_OK; /* allow set_errno action */
2097 goto RESPONSE_FAILED;
2100 /* Update the journal, or setup retry. */
2101 for (addr = addrlist; addr != first_addr; addr = addr->next)
2102 if (addr->transport_return == OK)
2104 if (testflag(addr, af_homonym))
2105 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2107 sprintf(CS buffer, "%.500s\n", addr->unique);
2109 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s", buffer);
2110 len = Ustrlen(CS buffer);
2111 if (write(journal_fd, buffer, len) != len)
2112 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2113 "%s: %s", buffer, strerror(errno));
2115 else if (addr->transport_return == DEFER)
2116 retry_add_item(addr, addr->address_retry_key, -2);
2120 /* Ensure the journal file is pushed out to disk. */
2122 if (EXIMfsync(journal_fd) < 0)
2123 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
2129 /* Handle general (not specific to one address) failures here. The value of ok
2130 is used to skip over this code on the falling through case. A timeout causes a
2131 deferral. Other errors may defer or fail according to the response code, and
2132 may set up a special errno value, e.g. after connection chopped, which is
2133 assumed if errno == 0 and there is no text in the buffer. If control reaches
2134 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
2135 the problem is not related to this specific message. */
2144 send_quit = check_response(host, &save_errno, addrlist->more_errno,
2145 buffer, &code, &message, &pass_message);
2151 message = US string_sprintf("send() to %s [%s] failed: %s",
2152 host->name, host->address, strerror(save_errno));
2156 /* This label is jumped to directly when a TLS negotiation has failed,
2157 or was not done for a host for which it is required. Values will be set
2158 in message and save_errno, and setting_up will always be true. Treat as
2159 a temporary error. */
2166 /* If the failure happened while setting up the call, see if the failure was
2167 a 5xx response (this will either be on connection, or following HELO - a 5xx
2168 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
2169 never going to accept them. For other errors during setting up (timeouts or
2170 whatever), defer all addresses, and yield DEFER, so that the host is not
2171 tried again for a while. */
2174 ok = FALSE; /* For when reached by GOTO */
2180 set_errno(addrlist, save_errno, message, FAIL, pass_message);
2184 set_errno(addrlist, save_errno, message, DEFER, pass_message);
2189 /* We want to handle timeouts after MAIL or "." and loss of connection after
2190 "." specially. They can indicate a problem with the sender address or with
2191 the contents of the message rather than a real error on the connection. These
2192 cases are treated in the same way as a 4xx response. This next bit of code
2193 does the classification. */
2204 message_error = TRUE;
2208 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
2209 Ustrncmp(smtp_command,"end ",4) == 0;
2212 case ERRNO_SMTPCLOSED:
2213 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
2217 message_error = FALSE;
2221 /* Handle the cases that are treated as message errors. These are:
2223 (a) negative response or timeout after MAIL
2224 (b) negative response after DATA
2225 (c) negative response or timeout or dropped connection after "."
2227 It won't be a negative response or timeout after RCPT, as that is dealt
2228 with separately above. The action in all cases is to set an appropriate
2229 error code for all the addresses, but to leave yield set to OK because the
2230 host itself has not failed. Of course, it might in practice have failed
2231 when we've had a timeout, but if so, we'll discover that at the next
2232 delivery attempt. For a temporary error, set the message_defer flag, and
2233 write to the logs for information if this is not the last host. The error
2234 for the last host will be logged as part of the address's log line. */
2238 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
2239 set_errno(addrlist, save_errno, message, (code == '5')? FAIL : DEFER,
2242 /* If there's an errno, the message contains just the identity of
2245 if (code != '5') /* Anything other than 5 is treated as temporary */
2248 message = US string_sprintf("%s: %s", message, strerror(save_errno));
2249 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
2250 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
2251 *message_defer = TRUE;
2255 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
2256 ".", or some other transportation error. We defer all addresses and yield
2257 DEFER, except for the case of failed add_headers expansion, or a transport
2258 filter failure, when the yield should be ERROR, to stop it trying other
2263 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
2264 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
2265 set_errno(addrlist, save_errno, message, DEFER, pass_message);
2271 /* If all has gone well, send_quit will be set TRUE, implying we can end the
2272 SMTP session tidily. However, if there were too many addresses to send in one
2273 message (indicated by first_addr being non-NULL) we want to carry on with the
2274 rest of them. Also, it is desirable to send more than one message down the SMTP
2275 connection if there are several waiting, provided we haven't already sent so
2276 many as to hit the configured limit. The function transport_check_waiting looks
2277 for a waiting message and returns its id. Then transport_pass_socket tries to
2278 set up a continued delivery by passing the socket on to another process. The
2279 variable send_rset is FALSE if a message has just been successfully transfered.
2281 If we are already sending down a continued channel, there may be further
2282 addresses not yet delivered that are aimed at the same host, but which have not
2283 been passed in this run of the transport. In this case, continue_more will be
2284 true, and all we should do is send RSET if necessary, and return, leaving the
2287 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
2288 do not want to continue with other messages down the same channel, because that
2289 can lead to looping between two or more messages, all with the same,
2290 temporarily failing address(es). [The retry information isn't updated yet, so
2291 new processes keep on trying.] We probably also don't want to try more of this
2292 message's addresses either.
2294 If we have started a TLS session, we have to end it before passing the
2295 connection to a new process. However, not all servers can handle this (Exim
2296 can), so we do not pass such a connection on if the host matches
2297 hosts_nopass_tls. */
2300 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
2301 "yield=%d first_address is %sNULL\n", ok, send_quit, send_rset,
2302 continue_more, yield, (first_addr == NULL)? "":"not ");
2304 if (completed_address && ok && send_quit)
2307 if (first_addr != NULL || continue_more ||
2309 (tls_out.active < 0 ||
2310 verify_check_this_host(&(ob->hosts_nopass_tls), NULL, host->name,
2311 host->address, NULL) != OK)
2313 transport_check_waiting(tblock->name, host->name,
2314 tblock->connection_max_messages, new_message_id, &more)
2322 if (! (ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
2324 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
2325 host->address, strerror(save_errno));
2328 else if (! (ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2329 ob->command_timeout)))
2332 send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
2336 DEBUG(D_transport) debug_printf("%s\n", msg);
2341 /* Either RSET was not needed, or it succeeded */
2345 if (first_addr != NULL) /* More addresses still to be sent */
2346 { /* in this run of the transport */
2347 continue_sequence++; /* Causes * in logging */
2350 if (continue_more) return yield; /* More addresses for another run */
2352 /* Pass the socket to a new Exim process. Before doing so, we must shut
2353 down TLS. Not all MTAs allow for the continuation of the SMTP session
2354 when TLS is shut down. We test for this by sending a new EHLO. If we
2355 don't get a good response, we don't attempt to pass the socket on. */
2358 if (tls_out.active >= 0)
2360 tls_close(FALSE, TRUE);
2364 ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
2365 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2366 ob->command_timeout);
2370 /* If the socket is successfully passed, we musn't send QUIT (or
2371 indeed anything!) from here. */
2373 if (ok && transport_pass_socket(tblock->name, host->name, host->address,
2374 new_message_id, inblock.sock))
2380 /* If RSET failed and there are addresses left, they get deferred. */
2382 else set_errno(first_addr, errno, msg, DEFER, FALSE);
2386 /* End off tidily with QUIT unless the connection has died or the socket has
2387 been passed to another process. There has been discussion on the net about what
2388 to do after sending QUIT. The wording of the RFC suggests that it is necessary
2389 to wait for a response, but on the other hand, there isn't anything one can do
2390 with an error response, other than log it. Exim used to do that. However,
2391 further discussion suggested that it is positively advantageous not to wait for
2392 the response, but to close the session immediately. This is supposed to move
2393 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
2394 load from the server. (Hosts that are both servers and clients may not see much
2395 difference, of course.) Further discussion indicated that this was safe to do
2396 on Unix systems which have decent implementations of TCP/IP that leave the
2397 connection around for a while (TIME_WAIT) after the application has gone away.
2398 This enables the response sent by the server to be properly ACKed rather than
2399 timed out, as can happen on broken TCP/IP implementations on other OS.
2401 This change is being made on 31-Jul-98. After over a year of trouble-free
2402 operation, the old commented-out code was removed on 17-Sep-99. */
2405 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2410 tls_close(FALSE, TRUE);
2413 /* Close the socket, and return the appropriate value, first setting
2414 continue_transport and continue_hostname NULL to prevent any other addresses
2415 that may include the host from trying to re-use a continuation socket. This
2416 works because the NULL setting is passed back to the calling process, and
2417 remote_max_parallel is forced to 1 when delivering over an existing connection,
2419 If all went well and continue_more is set, we shouldn't actually get here if
2420 there are further addresses, as the return above will be taken. However,
2421 writing RSET might have failed, or there may be other addresses whose hosts are
2422 specified in the transports, and therefore not visible at top level, in which
2423 case continue_more won't get set. */
2425 (void)close(inblock.sock);
2426 continue_transport = NULL;
2427 continue_hostname = NULL;
2434 /*************************************************
2435 * Closedown entry point *
2436 *************************************************/
2438 /* This function is called when exim is passed an open smtp channel
2439 from another incarnation, but the message which it has been asked
2440 to deliver no longer exists. The channel is on stdin.
2442 We might do fancy things like looking for another message to send down
2443 the channel, but if the one we sought has gone, it has probably been
2444 delivered by some other process that itself will seek further messages,
2445 so just close down our connection.
2447 Argument: pointer to the transport instance block
2452 smtp_transport_closedown(transport_instance *tblock)
2454 smtp_transport_options_block *ob =
2455 (smtp_transport_options_block *)(tblock->options_block);
2456 smtp_inblock inblock;
2457 smtp_outblock outblock;
2459 uschar inbuffer[4096];
2460 uschar outbuffer[16];
2462 inblock.sock = fileno(stdin);
2463 inblock.buffer = inbuffer;
2464 inblock.buffersize = sizeof(inbuffer);
2465 inblock.ptr = inbuffer;
2466 inblock.ptrend = inbuffer;
2468 outblock.sock = inblock.sock;
2469 outblock.buffersize = sizeof(outbuffer);
2470 outblock.buffer = outbuffer;
2471 outblock.ptr = outbuffer;
2472 outblock.cmd_count = 0;
2473 outblock.authenticating = FALSE;
2475 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2476 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2477 ob->command_timeout);
2478 (void)close(inblock.sock);
2483 /*************************************************
2484 * Prepare addresses for delivery *
2485 *************************************************/
2487 /* This function is called to flush out error settings from previous delivery
2488 attempts to other hosts. It also records whether we got here via an MX record
2489 or not in the more_errno field of the address. We are interested only in
2490 addresses that are still marked DEFER - others may have got delivered to a
2491 previously considered IP address. Set their status to PENDING_DEFER to indicate
2492 which ones are relevant this time.
2495 addrlist the list of addresses
2496 host the host we are delivering to
2498 Returns: the first address for this delivery
2501 static address_item *
2502 prepare_addresses(address_item *addrlist, host_item *host)
2504 address_item *first_addr = NULL;
2506 for (addr = addrlist; addr != NULL; addr = addr->next)
2508 if (addr->transport_return != DEFER) continue;
2509 if (first_addr == NULL) first_addr = addr;
2510 addr->transport_return = PENDING_DEFER;
2511 addr->basic_errno = 0;
2512 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
2513 addr->message = NULL;
2515 addr->cipher = NULL;
2516 addr->peerdn = NULL;
2524 /*************************************************
2525 * Main entry point *
2526 *************************************************/
2528 /* See local README for interface details. As this is a remote transport, it is
2529 given a chain of addresses to be delivered in one connection, if possible. It
2530 always returns TRUE, indicating that each address has its own independent
2531 status set, except if there is a setting up problem, in which case it returns
2535 smtp_transport_entry(
2536 transport_instance *tblock, /* data for this instantiation */
2537 address_item *addrlist) /* addresses we are working on */
2541 int hosts_defer = 0;
2543 int hosts_looked_up = 0;
2544 int hosts_retry = 0;
2545 int hosts_serial = 0;
2546 int hosts_total = 0;
2547 int total_hosts_tried = 0;
2549 BOOL expired = TRUE;
2550 BOOL continuing = continue_hostname != NULL;
2551 uschar *expanded_hosts = NULL;
2553 uschar *tid = string_sprintf("%s transport", tblock->name);
2554 smtp_transport_options_block *ob =
2555 (smtp_transport_options_block *)(tblock->options_block);
2556 host_item *hostlist = addrlist->host_list;
2557 host_item *host = NULL;
2561 debug_printf("%s transport entered\n", tblock->name);
2562 for (addr = addrlist; addr != NULL; addr = addr->next)
2563 debug_printf(" %s\n", addr->address);
2564 if (continuing) debug_printf("already connected to %s [%s]\n",
2565 continue_hostname, continue_host_address);
2568 /* Set the flag requesting that these hosts be added to the waiting
2569 database if the delivery fails temporarily or if we are running with
2570 queue_smtp or a 2-stage queue run. This gets unset for certain
2571 kinds of error, typically those that are specific to the message. */
2573 update_waiting = TRUE;
2575 /* If a host list is not defined for the addresses - they must all have the
2576 same one in order to be passed to a single transport - or if the transport has
2577 a host list with hosts_override set, use the host list supplied with the
2578 transport. It is an error for this not to exist. */
2580 if (hostlist == NULL || (ob->hosts_override && ob->hosts != NULL))
2582 if (ob->hosts == NULL)
2584 addrlist->message = string_sprintf("%s transport called with no hosts set",
2586 addrlist->transport_return = PANIC;
2587 return FALSE; /* Only top address has status */
2590 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
2593 /* If the transport's host list contains no '$' characters, and we are not
2594 randomizing, it is fixed and therefore a chain of hosts can be built once
2595 and for all, and remembered for subsequent use by other calls to this
2596 transport. If, on the other hand, the host list does contain '$', or we are
2597 randomizing its order, we have to rebuild it each time. In the fixed case,
2598 as the hosts string will never be used again, it doesn't matter that we
2599 replace all the : characters with zeros. */
2601 if (ob->hostlist == NULL)
2603 uschar *s = ob->hosts;
2605 if (Ustrchr(s, '$') != NULL)
2607 expanded_hosts = expand_string(s);
2608 if (expanded_hosts == NULL)
2610 addrlist->message = string_sprintf("failed to expand list of hosts "
2611 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
2612 addrlist->transport_return = search_find_defer? DEFER : PANIC;
2613 return FALSE; /* Only top address has status */
2615 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
2616 "\"%s\"\n", s, expanded_hosts);
2620 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
2622 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
2624 /* Check that the expansion yielded something useful. */
2625 if (hostlist == NULL)
2628 string_sprintf("%s transport has empty hosts setting", tblock->name);
2629 addrlist->transport_return = PANIC;
2630 return FALSE; /* Only top address has status */
2633 /* If there was no expansion of hosts, save the host list for
2636 if (expanded_hosts == NULL) ob->hostlist = hostlist;
2639 /* This is not the first time this transport has been run in this delivery;
2640 the host list was built previously. */
2642 else hostlist = ob->hostlist;
2645 /* The host list was supplied with the address. If hosts_randomize is set, we
2646 must sort it into a random order if it did not come from MX records and has not
2647 already been randomized (but don't bother if continuing down an existing
2650 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continuing)
2652 host_item *newlist = NULL;
2653 while (hostlist != NULL)
2655 host_item *h = hostlist;
2656 hostlist = hostlist->next;
2658 h->sort_key = random_number(100);
2660 if (newlist == NULL)
2665 else if (h->sort_key < newlist->sort_key)
2672 host_item *hh = newlist;
2673 while (hh->next != NULL)
2675 if (h->sort_key < hh->next->sort_key) break;
2683 hostlist = addrlist->host_list = newlist;
2687 /* Sort out the default port. */
2689 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
2692 /* For each host-plus-IP-address on the list:
2694 . If this is a continued delivery and the host isn't the one with the
2695 current connection, skip.
2697 . If the status is unusable (i.e. previously failed or retry checked), skip.
2699 . If no IP address set, get the address, either by turning the name into
2700 an address, calling gethostbyname if gethostbyname is on, or by calling
2701 the DNS. The DNS may yield multiple addresses, in which case insert the
2702 extra ones into the list.
2704 . Get the retry data if not previously obtained for this address and set the
2705 field which remembers the state of this address. Skip if the retry time is
2706 not reached. If not, remember whether retry data was found. The retry string
2707 contains both the name and the IP address.
2709 . Scan the list of addresses and mark those whose status is DEFER as
2710 PENDING_DEFER. These are the only ones that will be processed in this cycle
2713 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
2714 Some addresses may be successfully delivered, others may fail, and yet
2715 others may get temporary errors and so get marked DEFER.
2717 . The return from the delivery attempt is OK if a connection was made and a
2718 valid SMTP dialogue was completed. Otherwise it is DEFER.
2720 . If OK, add a "remove" retry item for this host/IPaddress, if any.
2722 . If fail to connect, or other defer state, add a retry item.
2724 . If there are any addresses whose status is still DEFER, carry on to the
2725 next host/IPaddress, unless we have tried the number of hosts given
2726 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
2727 there is some fancy logic for hosts_max_try that means its limit can be
2728 overstepped in some circumstances.
2730 If we get to the end of the list, all hosts have deferred at least one address,
2731 or not reached their retry times. If delay_after_cutoff is unset, it requests a
2732 delivery attempt to those hosts whose last try was before the arrival time of
2733 the current message. To cope with this, we have to go round the loop a second
2734 time. After that, set the status and error data for any addresses that haven't
2735 had it set already. */
2737 for (cutoff_retry = 0; expired &&
2738 cutoff_retry < ((ob->delay_after_cutoff)? 1 : 2);
2741 host_item *nexthost = NULL;
2742 int unexpired_hosts_tried = 0;
2744 for (host = hostlist;
2746 unexpired_hosts_tried < ob->hosts_max_try &&
2747 total_hosts_tried < ob->hosts_max_try_hardlimit;
2753 BOOL serialized = FALSE;
2754 BOOL host_is_expired = FALSE;
2755 BOOL message_defer = FALSE;
2756 BOOL ifchanges = FALSE;
2757 BOOL some_deferred = FALSE;
2758 address_item *first_addr = NULL;
2759 uschar *interface = NULL;
2760 uschar *retry_host_key = NULL;
2761 uschar *retry_message_key = NULL;
2762 uschar *serialize_key = NULL;
2764 /* Default next host is next host. :-) But this can vary if the
2765 hosts_max_try limit is hit (see below). It may also be reset if a host
2766 address is looked up here (in case the host was multihomed). */
2768 nexthost = host->next;
2770 /* If the address hasn't yet been obtained from the host name, look it up
2771 now, unless the host is already marked as unusable. If it is marked as
2772 unusable, it means that the router was unable to find its IP address (in
2773 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
2774 the lookup failed last time. We don't get this far if *all* MX records
2775 point to non-existent hosts; that is treated as a hard error.
2777 We can just skip this host entirely. When the hosts came from the router,
2778 the address will timeout based on the other host(s); when the address is
2779 looked up below, there is an explicit retry record added.
2781 Note that we mustn't skip unusable hosts if the address is not unset; they
2782 may be needed as expired hosts on the 2nd time round the cutoff loop. */
2784 if (host->address == NULL)
2786 int new_port, flags;
2788 uschar *canonical_name;
2790 if (host->status >= hstatus_unusable)
2792 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
2797 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
2799 /* The host name is permitted to have an attached port. Find it, and
2800 strip it from the name. Just remember it for now. */
2802 new_port = host_item_get_port(host);
2804 /* Count hosts looked up */
2808 /* Find by name if so configured, or if it's an IP address. We don't
2809 just copy the IP address, because we need the test-for-local to happen. */
2811 flags = HOST_FIND_BY_A;
2812 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
2813 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
2815 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
2816 rc = host_find_byname(host, NULL, flags, &canonical_name, TRUE);
2818 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
2819 &canonical_name, NULL);
2821 /* Update the host (and any additional blocks, resulting from
2822 multihoming) with a host-specific port, if any. */
2824 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
2826 /* Failure to find the host at this time (usually DNS temporary failure)
2827 is really a kind of routing failure rather than a transport failure.
2828 Therefore we add a retry item of the routing kind, not to stop us trying
2829 to look this name up here again, but to ensure the address gets timed
2830 out if the failures go on long enough. A complete failure at this point
2831 commonly points to a configuration error, but the best action is still
2832 to carry on for the next host. */
2834 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
2836 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
2838 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
2839 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
2840 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
2841 host->status = hstatus_unusable;
2843 for (addr = addrlist; addr != NULL; addr = addr->next)
2845 if (addr->transport_return != DEFER) continue;
2846 addr->basic_errno = ERRNO_UNKNOWNHOST;
2848 string_sprintf("failed to lookup IP address for %s", host->name);
2853 /* If the host is actually the local host, we may have a problem, or
2854 there may be some cunning configuration going on. In the problem case,
2855 log things and give up. The default transport status is already DEFER. */
2857 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
2859 for (addr = addrlist; addr != NULL; addr = addr->next)
2861 addr->basic_errno = 0;
2862 addr->message = string_sprintf("%s transport found host %s to be "
2863 "local", tblock->name, host->name);
2867 } /* End of block for IP address lookup */
2869 /* If this is a continued delivery, we are interested only in the host
2870 which matches the name of the existing open channel. The check is put
2871 here after the local host lookup, in case the name gets expanded as a
2872 result of the lookup. Set expired FALSE, to save the outer loop executing
2875 if (continuing && (Ustrcmp(continue_hostname, host->name) != 0 ||
2876 Ustrcmp(continue_host_address, host->address) != 0))
2879 continue; /* With next host */
2882 /* Reset the default next host in case a multihomed host whose addresses
2883 are not looked up till just above added to the host list. */
2885 nexthost = host->next;
2887 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
2888 domain is in queue_smtp_domains, we don't actually want to attempt any
2889 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
2890 there is a lookup defer in queue_smtp_domains, proceed as if the domain
2891 were not in it. We don't want to hold up all SMTP deliveries! Except when
2892 doing a two-stage queue run, don't do this if forcing. */
2894 if ((!deliver_force || queue_2stage) && (queue_smtp ||
2895 match_isinlist(addrlist->domain, &queue_smtp_domains, 0,
2896 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
2899 for (addr = addrlist; addr != NULL; addr = addr->next)
2901 if (addr->transport_return != DEFER) continue;
2902 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
2904 continue; /* With next host */
2907 /* Count hosts being considered - purely for an intelligent comment
2908 if none are usable. */
2912 /* Set $host and $host address now in case they are needed for the
2913 interface expansion or the serialize_hosts check; they remain set if an
2914 actual delivery happens. */
2916 deliver_host = host->name;
2917 deliver_host_address = host->address;
2919 /* Set up a string for adding to the retry key if the port number is not
2920 the standard SMTP port. A host may have its own port setting that overrides
2923 pistring = string_sprintf(":%d", (host->port == PORT_NONE)?
2925 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
2927 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
2928 string changes upon expansion, we must add it to the key that is used for
2929 retries, because connections to the same host from a different interface
2930 should be treated separately. */
2932 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET : AF_INET6;
2933 if (!smtp_get_interface(ob->interface, host_af, addrlist, &ifchanges,
2936 if (ifchanges) pistring = string_sprintf("%s/%s", pistring, interface);
2938 /* The first time round the outer loop, check the status of the host by
2939 inspecting the retry data. The second time round, we are interested only
2940 in expired hosts that haven't been tried since this message arrived. */
2942 if (cutoff_retry == 0)
2944 /* Ensure the status of the address is set by checking retry data if
2945 necessary. There maybe host-specific retry data (applicable to all
2946 messages) and also data for retries of a specific message at this host.
2947 If either of these retry records are actually read, the keys used are
2948 returned to save recomputing them later. */
2950 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
2951 ob->retry_include_ip_address, &retry_host_key, &retry_message_key);
2953 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
2954 (host->address == NULL)? US"" : host->address, pistring,
2955 (host->status == hstatus_usable)? "usable" :
2956 (host->status == hstatus_unusable)? "unusable" :
2957 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
2959 /* Skip this address if not usable at this time, noting if it wasn't
2960 actually expired, both locally and in the address. */
2962 switch (host->status)
2964 case hstatus_unusable:
2966 setflag(addrlist, af_retry_skipped);
2969 case hstatus_unusable_expired:
2972 case hwhy_retry: hosts_retry++; break;
2973 case hwhy_failed: hosts_fail++; break;
2974 case hwhy_deferred: hosts_defer++; break;
2977 /* If there was a retry message key, implying that previously there
2978 was a message-specific defer, we don't want to update the list of
2979 messages waiting for these hosts. */
2981 if (retry_message_key != NULL) update_waiting = FALSE;
2982 continue; /* With the next host or IP address */
2986 /* Second time round the loop: if the address is set but expired, and
2987 the message is newer than the last try, let it through. */
2991 if (host->address == NULL ||
2992 host->status != hstatus_unusable_expired ||
2993 host->last_try > received_time)
2996 debug_printf("trying expired host %s [%s]%s\n",
2997 host->name, host->address, pistring);
2998 host_is_expired = TRUE;
3001 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
3002 it remains TRUE only if all hosts are expired and none are actually tried.
3007 /* If this host is listed as one to which access must be serialized,
3008 see if another Exim process has a connection to it, and if so, skip
3009 this host. If not, update the database to record our connection to it
3010 and remember this for later deletion. Do not do any of this if we are
3011 sending the message down a pre-existing connection. */
3014 verify_check_this_host(&(ob->serialize_hosts), NULL, host->name,
3015 host->address, NULL) == OK)
3017 serialize_key = string_sprintf("host-serialize-%s", host->name);
3018 if (!enq_start(serialize_key))
3021 debug_printf("skipping host %s because another Exim process "
3022 "is connected to it\n", host->name);
3029 /* OK, we have an IP address that is not waiting for its retry time to
3030 arrive (it might be expired) OR (second time round the loop) we have an
3031 expired host that hasn't been tried since the message arrived. Have a go
3032 at delivering the message to it. First prepare the addresses by flushing
3033 out the result of previous attempts, and finding the first address that
3034 is still to be delivered. */
3036 first_addr = prepare_addresses(addrlist, host);
3038 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
3039 message_id, host->name, host->address, addrlist->address,
3040 (addrlist->next == NULL)? "" : ", ...");
3042 set_process_info("delivering %s to %s [%s] (%s%s)",
3043 message_id, host->name, host->address, addrlist->address,
3044 (addrlist->next == NULL)? "" : ", ...");
3046 /* This is not for real; don't do the delivery. If there are
3047 any remaining hosts, list them. */
3052 set_errno(addrlist, 0, NULL, OK, FALSE);
3053 for (addr = addrlist; addr != NULL; addr = addr->next)
3055 addr->host_used = host;
3056 addr->special_action = '*';
3057 addr->message = US"delivery bypassed by -N option";
3061 debug_printf("*** delivery by %s transport bypassed by -N option\n"
3062 "*** host and remaining hosts:\n", tblock->name);
3063 for (host2 = host; host2 != NULL; host2 = host2->next)
3064 debug_printf(" %s [%s]\n", host2->name,
3065 (host2->address == NULL)? US"unset" : host2->address);
3070 /* This is for real. If the host is expired, we don't count it for
3071 hosts_max_retry. This ensures that all hosts must expire before an address
3072 is timed out, unless hosts_max_try_hardlimit (which protects against
3073 lunatic DNS configurations) is reached.
3075 If the host is not expired and we are about to hit the hosts_max_retry
3076 limit, check to see if there is a subsequent hosts with a different MX
3077 value. If so, make that the next host, and don't count this one. This is a
3078 heuristic to make sure that different MXs do get tried. With a normal kind
3079 of retry rule, they would get tried anyway when the earlier hosts were
3080 delayed, but if the domain has a "retry every time" type of rule - as is
3081 often used for the the very large ISPs, that won't happen. */
3085 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
3089 debug_printf("hosts_max_try limit reached with this host\n");
3090 for (h = host; h != NULL; h = h->next)
3091 if (h->mx != host->mx) break;
3095 unexpired_hosts_tried--;
3096 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
3097 "and will be tried\n");
3101 /* Attempt the delivery. */
3103 total_hosts_tried++;
3104 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
3105 expanded_hosts != NULL, &message_defer, FALSE);
3108 OK => connection made, each address contains its result;
3109 message_defer is set for message-specific defers (when all
3110 recipients are marked defer)
3111 DEFER => there was a non-message-specific delivery problem;
3112 ERROR => there was a problem setting up the arguments for a filter,
3113 or there was a problem with expanding added headers
3116 /* If the result is not OK, there was a non-message-specific problem.
3117 If the result is DEFER, we need to write to the logs saying what happened
3118 for this particular host, except in the case of authentication and TLS
3119 failures, where the log has already been written. If all hosts defer a
3120 general message is written at the end. */
3122 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL &&
3123 first_addr->basic_errno != ERRNO_TLSFAILURE)
3124 write_logs(first_addr, host);
3126 #ifdef EXPERIMENTAL_TPDA
3128 tpda_deferred(ob, first_addr, host);
3131 /* If STARTTLS was accepted, but there was a failure in setting up the
3132 TLS session (usually a certificate screwup), and the host is not in
3133 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
3134 TLS forcibly turned off. We have to start from scratch with a new SMTP
3135 connection. That's why the retry is done from here, not from within
3136 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
3137 session, so the in-clear transmission after those errors, if permitted,
3138 happens inside smtp_deliver().] */
3141 if (rc == DEFER && first_addr->basic_errno == ERRNO_TLSFAILURE &&
3142 ob->tls_tempfail_tryclear &&
3143 verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
3144 host->address, NULL) != OK)
3146 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
3147 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
3148 first_addr = prepare_addresses(addrlist, host);
3149 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
3150 expanded_hosts != NULL, &message_defer, TRUE);
3151 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
3152 write_logs(first_addr, host);
3153 #ifdef EXPERIMENTAL_TPDA
3155 tpda_deferred(ob, first_addr, host);
3161 /* Delivery attempt finished */
3163 rs = (rc == OK)? US"OK" : (rc == DEFER)? US"DEFER" : (rc == ERROR)?
3166 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
3167 message_id, host->name, host->address, addrlist->address,
3168 (addrlist->next == NULL)? "" : " (& others)", rs);
3170 /* Release serialization if set up */
3172 if (serialized) enq_end(serialize_key);
3174 /* If the result is DEFER, or if a host retry record is known to exist, we
3175 need to add an item to the retry chain for updating the retry database
3176 at the end of delivery. We only need to add the item to the top address,
3177 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
3178 for any other delivery attempts using the same address. (It is copied into
3179 the unusable tree at the outer level, so even if different address blocks
3180 contain the same address, it still won't get tried again.) */
3182 if (rc == DEFER || retry_host_key != NULL)
3184 int delete_flag = (rc != DEFER)? rf_delete : 0;
3185 if (retry_host_key == NULL)
3187 retry_host_key = ob->retry_include_ip_address?
3188 string_sprintf("T:%S:%s%s", host->name, host->address, pistring) :
3189 string_sprintf("T:%S%s", host->name, pistring);
3192 /* If a delivery of another message over an existing SMTP connection
3193 yields DEFER, we do NOT set up retry data for the host. This covers the
3194 case when there are delays in routing the addresses in the second message
3195 that are so long that the server times out. This is alleviated by not
3196 routing addresses that previously had routing defers when handling an
3197 existing connection, but even so, this case may occur (e.g. if a
3198 previously happily routed address starts giving routing defers). If the
3199 host is genuinely down, another non-continued message delivery will
3200 notice it soon enough. */
3202 if (delete_flag != 0 || !continuing)
3203 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
3205 /* We may have tried an expired host, if its retry time has come; ensure
3206 the status reflects the expiry for the benefit of any other addresses. */
3210 host->status = (host_is_expired)?
3211 hstatus_unusable_expired : hstatus_unusable;
3212 host->why = hwhy_deferred;
3216 /* If message_defer is set (host was OK, but every recipient got deferred
3217 because of some message-specific problem), or if that had happened
3218 previously so that a message retry key exists, add an appropriate item
3219 to the retry chain. Note that if there was a message defer but now there is
3220 a host defer, the message defer record gets deleted. That seems perfectly
3221 reasonable. Also, stop the message from being remembered as waiting
3222 for specific hosts. */
3224 if (message_defer || retry_message_key != NULL)
3226 int delete_flag = message_defer? 0 : rf_delete;
3227 if (retry_message_key == NULL)
3229 retry_message_key = ob->retry_include_ip_address?
3230 string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
3232 string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
3234 retry_add_item(addrlist, retry_message_key,
3235 rf_message | rf_host | delete_flag);
3236 update_waiting = FALSE;
3239 /* Any return other than DEFER (that is, OK or ERROR) means that the
3240 addresses have got their final statuses filled in for this host. In the OK
3241 case, see if any of them are deferred. */
3245 for (addr = addrlist; addr != NULL; addr = addr->next)
3247 if (addr->transport_return == DEFER)
3249 some_deferred = TRUE;
3255 /* If no addresses deferred or the result was ERROR, return. We do this for
3256 ERROR because a failing filter set-up or add_headers expansion is likely to
3257 fail for any host we try. */
3259 if (rc == ERROR || (rc == OK && !some_deferred))
3261 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3262 return TRUE; /* Each address has its status */
3265 /* If the result was DEFER or some individual addresses deferred, let
3266 the loop run to try other hosts with the deferred addresses, except for the
3267 case when we were trying to deliver down an existing channel and failed.
3268 Don't try any other hosts in this case. */
3270 if (continuing) break;
3272 /* If the whole delivery, or some individual addresses, were deferred and
3273 there are more hosts that could be tried, do not count this host towards
3274 the hosts_max_try limit if the age of the message is greater than the
3275 maximum retry time for this host. This means we may try try all hosts,
3276 ignoring the limit, when messages have been around for some time. This is
3277 important because if we don't try all hosts, the address will never time
3278 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
3280 if ((rc == DEFER || some_deferred) && nexthost != NULL)
3283 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
3285 if (retry != NULL && retry->rules != NULL)
3287 retry_rule *last_rule;
3288 for (last_rule = retry->rules;
3289 last_rule->next != NULL;
3290 last_rule = last_rule->next);
3291 timedout = time(NULL) - received_time > last_rule->timeout;
3293 else timedout = TRUE; /* No rule => timed out */
3297 unexpired_hosts_tried--;
3298 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
3299 "hosts_max_try (message older than host's retry time)\n");
3302 } /* End of loop for trying multiple hosts. */
3304 /* This is the end of the loop that repeats iff expired is TRUE and
3305 ob->delay_after_cutoff is FALSE. The second time round we will
3306 try those hosts that haven't been tried since the message arrived. */
3310 debug_printf("all IP addresses skipped or deferred at least one address\n");
3311 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
3312 debug_printf("retrying IP addresses not tried since message arrived\n");
3317 /* Get here if all IP addresses are skipped or defer at least one address. In
3318 MUA wrapper mode, this will happen only for connection or other non-message-
3319 specific failures. Force the delivery status for all addresses to FAIL. */
3323 for (addr = addrlist; addr != NULL; addr = addr->next)
3324 addr->transport_return = FAIL;
3328 /* In the normal, non-wrapper case, add a standard message to each deferred
3329 address if there hasn't been an error, that is, if it hasn't actually been
3330 tried this time. The variable "expired" will be FALSE if any deliveries were
3331 actually tried, or if there was at least one host that was not expired. That
3332 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
3333 a delivery has been tried, an error code will be set, and the failing of the
3334 message is handled by the retry code later.
3336 If queue_smtp is set, or this transport was called to send a subsequent message
3337 down an existing TCP/IP connection, and something caused the host not to be
3338 found, we end up here, but can detect these cases and handle them specially. */
3340 for (addr = addrlist; addr != NULL; addr = addr->next)
3342 /* If host is not NULL, it means that we stopped processing the host list
3343 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
3344 means we need to behave as if some hosts were skipped because their retry
3345 time had not come. Specifically, this prevents the address from timing out.
3346 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
3347 hosts were tried. */
3351 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
3354 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
3355 "hosts were tried\n");
3360 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
3361 setflag(addr, af_retry_skipped);
3365 if (queue_smtp) /* no deliveries attempted */
3367 addr->transport_return = DEFER;
3368 addr->basic_errno = 0;
3369 addr->message = US"SMTP delivery explicitly queued";
3372 else if (addr->transport_return == DEFER &&
3373 (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0) &&
3374 addr->message == NULL)
3376 addr->basic_errno = ERRNO_HRETRY;
3377 if (continue_hostname != NULL)
3379 addr->message = US"no host found for existing SMTP connection";
3383 setflag(addr, af_pass_message); /* This is not a security risk */
3384 addr->message = (ob->delay_after_cutoff)?
3385 US"retry time not reached for any host after a long failure period" :
3386 US"all hosts have been failing for a long time and were last tried "
3387 "after this message arrived";
3389 /* If we are already using fallback hosts, or there are no fallback hosts
3390 defined, convert the result to FAIL to cause a bounce. */
3392 if (addr->host_list == addr->fallback_hosts ||
3393 addr->fallback_hosts == NULL)
3394 addr->transport_return = FAIL;
3398 if (hosts_retry == hosts_total)
3399 addr->message = US"retry time not reached for any host";
3400 else if (hosts_fail == hosts_total)
3401 addr->message = US"all host address lookups failed permanently";
3402 else if (hosts_defer == hosts_total)
3403 addr->message = US"all host address lookups failed temporarily";
3404 else if (hosts_serial == hosts_total)
3405 addr->message = US"connection limit reached for all hosts";
3406 else if (hosts_fail+hosts_defer == hosts_total)
3407 addr->message = US"all host address lookups failed";
3408 else addr->message = US"some host address lookups failed and retry time "
3409 "not reached for other hosts or connection limit reached";
3414 /* Update the database which keeps information about which messages are waiting
3415 for which hosts to become available. For some message-specific errors, the
3416 update_waiting flag is turned off because we don't want follow-on deliveries in
3417 those cases. If this transport instance is explicitly limited to one message
3418 per connection then follow-on deliveries are not possible and there's no need
3419 to create/update the per-transport wait-<transport_name> database. */
3421 if (update_waiting && tblock->connection_max_messages != 1)
3422 transport_update_waiting(hostlist, tblock->name);
3426 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3428 return TRUE; /* Each address has its status */
3431 /* End of transport/smtp.c */