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_in.cipher = NULL; /* for back-compatible behaviour */
1218 tls_in.peerdn = NULL;
1219 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1224 tls_out.cipher = NULL; /* the one we may use for this transport */
1225 tls_out.peerdn = NULL;
1226 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1233 set_errno(addrlist, 0, US"TLS support not available", DEFER, FALSE);
1238 /* Make a connection to the host if this isn't a continued delivery, and handle
1239 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
1240 specially so they can be identified for retries. */
1242 if (continue_hostname == NULL)
1244 inblock.sock = outblock.sock =
1245 smtp_connect(host, host_af, port, interface, ob->connect_timeout,
1246 ob->keepalive, ob->dscp); /* This puts port into host->port */
1248 if (inblock.sock < 0)
1250 set_errno(addrlist, (errno == ETIMEDOUT)? ERRNO_CONNECTTIMEOUT : errno,
1251 NULL, DEFER, FALSE);
1255 /* Expand the greeting message while waiting for the initial response. (Makes
1256 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1257 delayed till here so that $sending_interface and $sending_port are set. */
1259 helo_data = expand_string(ob->helo_data);
1261 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1262 is nevertheless a reasonably clean way of programming this kind of logic,
1263 where you want to escape on any error. */
1267 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1268 ob->command_timeout)) goto RESPONSE_FAILED;
1270 /* Now check if the helo_data expansion went well, and sign off cleanly if
1273 if (helo_data == NULL)
1275 uschar *message = string_sprintf("failed to expand helo_data: %s",
1276 expand_string_message);
1277 set_errno(addrlist, 0, message, DEFER, FALSE);
1283 /** Debugging without sending a message
1284 addrlist->transport_return = DEFER;
1288 /* Errors that occur after this point follow an SMTP command, which is
1289 left in big_buffer by smtp_write_command() for use in error messages. */
1291 smtp_command = big_buffer;
1293 /* Tell the remote who we are...
1295 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1296 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1297 greeting is of this form. The assumption was that the far end supports it
1298 properly... but experience shows that there are some that give 5xx responses,
1299 even though the banner includes "ESMTP" (there's a bloody-minded one that
1300 says "ESMTP not spoken here"). Cope with that case.
1302 September 2000: Time has passed, and it seems reasonable now to always send
1303 EHLO at the start. It is also convenient to make the change while installing
1306 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1307 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1308 would be no way to send out the mails, so there is now a host list
1309 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1310 PIPELINING problem as well. Maybe it can also be useful to cure other
1311 problems with broken servers.
1313 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1314 Then somebody tried it with a Microsoft mailer... It seems that all other
1315 mailers use upper case for some reason (the RFC is quite clear about case
1316 independence) so, for peace of mind, I gave in. */
1318 esmtp = verify_check_this_host(&(ob->hosts_avoid_esmtp), NULL,
1319 host->name, host->address, NULL) != OK;
1321 /* Alas; be careful, since this goto is not an error-out, so conceivably
1322 we might set data between here and the target which we assume to exist
1323 and be usable. I can see this coming back to bite us. */
1328 suppress_tls = FALSE;
1329 ob->tls_tempfail_tryclear = FALSE;
1330 smtp_command = US"SSL-on-connect";
1337 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1338 lmtp? "LHLO" : "EHLO", helo_data) < 0)
1340 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1341 ob->command_timeout))
1343 if (errno != 0 || buffer[0] == 0 || lmtp) goto RESPONSE_FAILED;
1350 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1355 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1357 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1358 ob->command_timeout)) goto RESPONSE_FAILED;
1361 /* Set IGNOREQUOTA if the response to LHLO specifies support and the
1362 lmtp_ignore_quota option was set. */
1364 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1365 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1366 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1368 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1371 tls_offered = esmtp &&
1372 pcre_exec(regex_STARTTLS, NULL, CS buffer, Ustrlen(buffer), 0,
1373 PCRE_EOPT, NULL, 0) >= 0;
1376 #ifdef EXPERIMENTAL_PRDR
1377 prdr_offered = esmtp &&
1378 (pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(buffer), 0,
1379 PCRE_EOPT, NULL, 0) >= 0) &&
1380 (verify_check_this_host(&(ob->hosts_try_prdr), NULL, host->name,
1381 host->address, NULL) == OK);
1384 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1388 /* For continuing deliveries down the same channel, the socket is the standard
1389 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1390 below). Set up the pointer to where subsequent commands will be left, for
1391 error messages. Note that smtp_use_size and smtp_use_pipelining will have been
1392 set from the command line if they were set in the process that passed the
1397 inblock.sock = outblock.sock = fileno(stdin);
1398 smtp_command = big_buffer;
1399 host->port = port; /* Record the port that was used */
1402 /* If TLS is available on this connection, whether continued or not, attempt to
1403 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1404 send another EHLO - the server may give a different answer in secure mode. We
1405 use a separate buffer for reading the response to STARTTLS so that if it is
1406 negative, the original EHLO data is available for subsequent analysis, should
1407 the client not be required to use TLS. If the response is bad, copy the buffer
1408 for error analysis. */
1411 if (tls_offered && !suppress_tls &&
1412 verify_check_this_host(&(ob->hosts_avoid_tls), NULL, host->name,
1413 host->address, NULL) != OK)
1415 uschar buffer2[4096];
1416 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1419 /* If there is an I/O error, transmission of this message is deferred. If
1420 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1421 false, we also defer. However, if there is a temporary rejection of STARTTLS
1422 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1423 STARTTLS, we carry on. This means we will try to send the message in clear,
1424 unless the host is in hosts_require_tls (tested below). */
1426 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1427 ob->command_timeout))
1429 if (errno != 0 || buffer2[0] == 0 ||
1430 (buffer2[0] == '4' && !ob->tls_tempfail_tryclear))
1432 Ustrncpy(buffer, buffer2, sizeof(buffer));
1433 goto RESPONSE_FAILED;
1437 /* STARTTLS accepted: try to negotiate a TLS session. */
1442 int rc = tls_client_start(inblock.sock,
1445 ob->tls_certificate,
1448 ob->tls_verify_certificates,
1450 ob->tls_require_ciphers,
1451 #ifdef EXPERIMENTAL_OCSP
1452 ob->hosts_require_ocsp,
1454 ob->tls_dh_min_bits,
1455 ob->command_timeout,
1456 ob->tls_verify_hosts,
1457 ob->tls_try_verify_hosts);
1459 /* TLS negotiation failed; give an error. From outside, this function may
1460 be called again to try in clear on a new connection, if the options permit
1461 it for this host. */
1465 save_errno = ERRNO_TLSFAILURE;
1466 message = US"failure while setting up TLS session";
1471 /* TLS session is set up */
1473 for (addr = addrlist; addr != NULL; addr = addr->next)
1475 if (addr->transport_return == PENDING_DEFER)
1477 addr->cipher = tls_out.cipher;
1478 addr->peerdn = tls_out.peerdn;
1484 /* if smtps, we'll have smtp_command set to something else; always safe to
1486 smtp_command = big_buffer;
1488 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1489 helo_data is null, we are dealing with a connection that was passed from
1490 another process, and so we won't have expanded helo_data above. We have to
1491 expand it here. $sending_ip_address and $sending_port are set up right at the
1492 start of the Exim process (in exim.c). */
1494 if (tls_out.active >= 0)
1497 if (helo_data == NULL)
1499 helo_data = expand_string(ob->helo_data);
1500 if (helo_data == NULL)
1502 uschar *message = string_sprintf("failed to expand helo_data: %s",
1503 expand_string_message);
1504 set_errno(addrlist, 0, message, DEFER, FALSE);
1510 /* For SMTPS we need to wait for the initial OK response. */
1513 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1514 ob->command_timeout)) goto RESPONSE_FAILED;
1518 greeting_cmd = "EHLO";
1521 greeting_cmd = "HELO";
1523 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1526 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1527 lmtp? "LHLO" : greeting_cmd, helo_data) < 0)
1529 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1530 ob->command_timeout))
1531 goto RESPONSE_FAILED;
1534 /* If the host is required to use a secure channel, ensure that we
1537 else if (verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
1538 host->address, NULL) == OK)
1540 save_errno = ERRNO_TLSREQUIRED;
1541 message = string_sprintf("a TLS session is required for %s [%s], but %s",
1542 host->name, host->address,
1543 tls_offered? "an attempt to start TLS failed" :
1544 "the server did not offer TLS support");
1549 /* If TLS is active, we have just started it up and re-done the EHLO command,
1550 so its response needs to be analyzed. If TLS is not active and this is a
1551 continued session down a previously-used socket, we haven't just done EHLO, so
1554 if (continue_hostname == NULL
1556 || tls_out.active >= 0
1560 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
1561 lmtp_ignore_quota option was set. */
1563 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1564 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1565 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1567 /* If the response to EHLO specified support for the SIZE parameter, note
1568 this, provided size_addition is non-negative. */
1570 smtp_use_size = esmtp && ob->size_addition >= 0 &&
1571 pcre_exec(regex_SIZE, NULL, CS buffer, Ustrlen(CS buffer), 0,
1572 PCRE_EOPT, NULL, 0) >= 0;
1574 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
1575 the current host, esmtp will be false, so PIPELINING can never be used. If
1576 the current host matches hosts_avoid_pipelining, don't do it. */
1578 smtp_use_pipelining = esmtp &&
1579 verify_check_this_host(&(ob->hosts_avoid_pipelining), NULL, host->name,
1580 host->address, NULL) != OK &&
1581 pcre_exec(regex_PIPELINING, NULL, CS buffer, Ustrlen(CS buffer), 0,
1582 PCRE_EOPT, NULL, 0) >= 0;
1584 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
1585 smtp_use_pipelining? "" : "not ");
1587 #ifdef EXPERIMENTAL_PRDR
1588 prdr_offered = esmtp &&
1589 pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(CS buffer), 0,
1590 PCRE_EOPT, NULL, 0) >= 0 &&
1591 verify_check_this_host(&(ob->hosts_try_prdr), NULL, host->name,
1592 host->address, NULL) == OK;
1595 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1598 /* Note if the response to EHLO specifies support for the AUTH extension.
1599 If it has, check that this host is one we want to authenticate to, and do
1600 the business. The host name and address must be available when the
1601 authenticator's client driver is running. */
1603 switch (yield = smtp_auth(buffer, sizeof(buffer), addrlist, host,
1604 ob, esmtp, &inblock, &outblock))
1606 default: goto SEND_QUIT;
1608 case FAIL_SEND: goto SEND_FAILED;
1609 case FAIL: goto RESPONSE_FAILED;
1613 /* The setting up of the SMTP call is now complete. Any subsequent errors are
1614 message-specific. */
1618 /* If there is a filter command specified for this transport, we can now
1619 set it up. This cannot be done until the identify of the host is known. */
1621 if (tblock->filter_command != NULL)
1625 sprintf(CS buffer, "%.50s transport", tblock->name);
1626 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
1627 TRUE, DEFER, addrlist, buffer, NULL);
1628 transport_filter_timeout = tblock->filter_timeout;
1630 /* On failure, copy the error to all addresses, abandon the SMTP call, and
1635 set_errno(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
1643 /* For messages that have more than the maximum number of envelope recipients,
1644 we want to send several transactions down the same SMTP connection. (See
1645 comments in deliver.c as to how this reconciles, heuristically, with
1646 remote_max_parallel.) This optimization was added to Exim after the following
1647 code was already working. The simplest way to put it in without disturbing the
1648 code was to use a goto to jump back to this point when there is another
1649 transaction to handle. */
1652 sync_addr = first_addr;
1656 completed_address = FALSE;
1659 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
1660 qualification, send it, adding something to the message size to allow for
1661 imprecision and things that get added en route. Exim keeps the number of lines
1662 in a message, so we can give an accurate value for the original message, but we
1663 need some additional to handle added headers. (Double "." characters don't get
1664 included in the count.) */
1671 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
1675 #ifdef EXPERIMENTAL_PRDR
1676 prdr_active = FALSE;
1679 for (addr = first_addr; addr; addr = addr->next)
1680 if (addr->transport_return == PENDING_DEFER)
1682 for (addr = addr->next; addr; addr = addr->next)
1683 if (addr->transport_return == PENDING_DEFER)
1684 { /* at least two recipients to send */
1686 sprintf(CS p, " PRDR"); p += 5;
1687 goto prdr_is_active;
1695 /* If an authenticated_sender override has been specified for this transport
1696 instance, expand it. If the expansion is forced to fail, and there was already
1697 an authenticated_sender for this message, the original value will be used.
1698 Other expansion failures are serious. An empty result is ignored, but there is
1699 otherwise no check - this feature is expected to be used with LMTP and other
1700 cases where non-standard addresses (e.g. without domains) might be required. */
1702 if (smtp_mail_auth_str(p, sizeof(buffer) - (p-buffer), addrlist, ob))
1705 /* From here until we send the DATA command, we can make use of PIPELINING
1706 if the server host supports it. The code has to be able to check the responses
1707 at any point, for when the buffer fills up, so we write it totally generally.
1708 When PIPELINING is off, each command written reports that it has flushed the
1711 pending_MAIL = TRUE; /* The block starts with MAIL */
1713 rc = smtp_write_command(&outblock, smtp_use_pipelining,
1714 "MAIL FROM:<%s>%s\r\n", return_path, buffer);
1715 mail_command = string_copy(big_buffer); /* Save for later error message */
1719 case -1: /* Transmission error */
1722 case +1: /* Block was sent */
1723 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1724 ob->command_timeout))
1726 if (errno == 0 && buffer[0] == '4')
1728 errno = ERRNO_MAIL4XX;
1729 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1731 goto RESPONSE_FAILED;
1733 pending_MAIL = FALSE;
1737 /* Pass over all the relevant recipient addresses for this host, which are the
1738 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
1739 several before we have to read the responses for those seen so far. This
1740 checking is done by a subroutine because it also needs to be done at the end.
1741 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
1742 the next one if not all are sent.
1744 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
1745 last address because we want to abort if any recipients have any kind of
1746 problem, temporary or permanent. We know that all recipient addresses will have
1747 the PENDING_DEFER status, because only one attempt is ever made, and we know
1748 that max_rcpt will be large, so all addresses will be done at once. */
1750 for (addr = first_addr;
1751 address_count < max_rcpt && addr != NULL;
1757 if (addr->transport_return != PENDING_DEFER) continue;
1760 no_flush = smtp_use_pipelining && (!mua_wrapper || addr->next != NULL);
1762 /* Now send the RCPT command, and process outstanding responses when
1763 necessary. After a timeout on RCPT, we just end the function, leaving the
1764 yield as OK, because this error can often mean that there is a problem with
1765 just one address, so we don't want to delay the host. */
1767 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s\r\n",
1768 transport_rcpt_address(addr, tblock->rcpt_include_affixes), igquotstr);
1769 if (count < 0) goto SEND_FAILED;
1772 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
1773 &sync_addr, host, count, ob->address_retry_include_sender,
1774 pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
1777 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1778 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1781 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1782 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1783 case 0: /* No 2xx or 5xx, but no probs */
1786 case -1: goto END_OFF; /* Timeout on RCPT */
1787 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
1789 pending_MAIL = FALSE; /* Dealt with MAIL */
1791 } /* Loop for next address */
1793 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
1794 permanently or temporarily. We should have flushed and synced after the last
1799 address_item *badaddr;
1800 for (badaddr = first_addr; badaddr != NULL; badaddr = badaddr->next)
1802 if (badaddr->transport_return != PENDING_OK) break;
1804 if (badaddr != NULL)
1806 set_errno(addrlist, 0, badaddr->message, FAIL,
1807 testflag(badaddr, af_pass_message));
1812 /* If ok is TRUE, we know we have got at least one good recipient, and must now
1813 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
1814 have a good recipient buffered up if we are pipelining. We don't want to waste
1815 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
1816 are pipelining. The responses are all handled by sync_responses(). */
1818 if (ok || (smtp_use_pipelining && !mua_wrapper))
1820 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
1821 if (count < 0) goto SEND_FAILED;
1822 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
1823 host, count, ob->address_retry_include_sender, pending_MAIL,
1824 ok? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
1826 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1827 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1830 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1831 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1832 case 0: break; /* No 2xx or 5xx, but no probs */
1834 case -1: goto END_OFF; /* Timeout on RCPT */
1835 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
1839 /* Save the first address of the next batch. */
1843 /* If there were no good recipients (but otherwise there have been no
1844 problems), just set ok TRUE, since we have handled address-specific errors
1845 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
1846 for handling the SMTP dot-handling protocol, flagging to apply to headers as
1847 well as body. Set the appropriate timeout value to be used for each chunk.
1848 (Haven't been able to make it work using select() for writing yet.) */
1850 if (!ok) ok = TRUE; else
1852 sigalrm_seen = FALSE;
1853 transport_write_timeout = ob->data_timeout;
1854 smtp_command = US"sending data block"; /* For error messages */
1855 DEBUG(D_transport|D_v)
1856 debug_printf(" SMTP>> writing message and terminating \".\"\n");
1857 transport_count = 0;
1858 #ifndef DISABLE_DKIM
1859 ok = dkim_transport_write_message(addrlist, inblock.sock,
1860 topt_use_crlf | topt_end_dot | topt_escape_headers |
1861 (tblock->body_only? topt_no_headers : 0) |
1862 (tblock->headers_only? topt_no_body : 0) |
1863 (tblock->return_path_add? topt_add_return_path : 0) |
1864 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1865 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1866 0, /* No size limit */
1867 tblock->add_headers, tblock->remove_headers,
1868 US".", US"..", /* Escaping strings */
1869 tblock->rewrite_rules, tblock->rewrite_existflags,
1870 ob->dkim_private_key, ob->dkim_domain, ob->dkim_selector,
1871 ob->dkim_canon, ob->dkim_strict, ob->dkim_sign_headers
1874 ok = transport_write_message(addrlist, inblock.sock,
1875 topt_use_crlf | topt_end_dot | topt_escape_headers |
1876 (tblock->body_only? topt_no_headers : 0) |
1877 (tblock->headers_only? topt_no_body : 0) |
1878 (tblock->return_path_add? topt_add_return_path : 0) |
1879 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1880 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1881 0, /* No size limit */
1882 tblock->add_headers, tblock->remove_headers,
1883 US".", US"..", /* Escaping strings */
1884 tblock->rewrite_rules, tblock->rewrite_existflags);
1887 /* transport_write_message() uses write() because it is called from other
1888 places to write to non-sockets. This means that under some OS (e.g. Solaris)
1889 it can exit with "Broken pipe" as its error. This really means that the
1890 socket got closed at the far end. */
1892 transport_write_timeout = 0; /* for subsequent transports */
1894 /* Failure can either be some kind of I/O disaster (including timeout),
1895 or the failure of a transport filter or the expansion of added headers. */
1899 buffer[0] = 0; /* There hasn't been a response */
1900 goto RESPONSE_FAILED;
1903 /* We used to send the terminating "." explicitly here, but because of
1904 buffering effects at both ends of TCP/IP connections, you don't gain
1905 anything by keeping it separate, so it might as well go in the final
1906 data buffer for efficiency. This is now done by setting the topt_end_dot
1909 smtp_command = US"end of data";
1911 #ifdef EXPERIMENTAL_PRDR
1912 /* For PRDR we optionally get a partial-responses warning
1913 * followed by the individual responses, before going on with
1914 * the overall response. If we don't get the warning then deal
1915 * with per non-PRDR. */
1918 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '3',
1920 if (!ok && errno == 0)
1923 case '2': prdr_active = FALSE;
1926 case '4': errno = ERRNO_DATA4XX;
1927 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1934 /* For non-PRDR SMTP, we now read a single response that applies to the
1935 whole message. If it is OK, then all the addresses have been delivered. */
1939 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1941 if (!ok && errno == 0 && buffer[0] == '4')
1943 errno = ERRNO_DATA4XX;
1944 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1948 /* For LMTP, we get back a response for every RCPT command that we sent;
1949 some may be accepted and some rejected. For those that get a response, their
1950 status is fixed; any that are accepted have been handed over, even if later
1951 responses crash - at least, that's how I read RFC 2033.
1953 If all went well, mark the recipient addresses as completed, record which
1954 host/IPaddress they were delivered to, and cut out RSET when sending another
1955 message down the same channel. Write the completed addresses to the journal
1956 now so that they are recorded in case there is a crash of hardware or
1957 software before the spool gets updated. Also record the final SMTP
1958 confirmation if needed (for SMTP only). */
1963 int delivery_time = (int)(time(NULL) - start_delivery_time);
1966 uschar *conf = NULL;
1969 /* Make a copy of the host if it is local to this invocation
1970 of the transport. */
1974 thost = store_get(sizeof(host_item));
1976 thost->name = string_copy(host->name);
1977 thost->address = string_copy(host->address);
1981 /* Set up confirmation if needed - applies only to SMTP */
1984 #ifndef EXPERIMENTAL_TPDA
1985 (log_extra_selector & LX_smtp_confirmation) != 0 &&
1990 uschar *s = string_printing(buffer);
1991 conf = (s == buffer)? (uschar *)string_copy(s) : s;
1994 /* Process all transported addresses - for LMTP or PRDR, read a status for
1997 for (addr = addrlist; addr != first_addr; addr = addr->next)
1999 if (addr->transport_return != PENDING_OK) continue;
2001 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
2002 remaining addresses. Otherwise, it's a return code for just the one
2003 address. For temporary errors, add a retry item for the address so that
2004 it doesn't get tried again too soon. */
2006 #ifdef EXPERIMENTAL_PRDR
2007 if (lmtp || prdr_active)
2012 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2015 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
2016 addr->message = string_sprintf(
2017 #ifdef EXPERIMENTAL_PRDR
2018 "%s error after %s: %s", prdr_active ? "PRDR":"LMTP",
2020 "LMTP error after %s: %s",
2022 big_buffer, string_printing(buffer));
2023 setflag(addr, af_pass_message); /* Allow message to go to user */
2024 if (buffer[0] == '5')
2025 addr->transport_return = FAIL;
2028 errno = ERRNO_DATA4XX;
2029 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2030 addr->transport_return = DEFER;
2031 #ifdef EXPERIMENTAL_PRDR
2034 retry_add_item(addr, addr->address_retry_key, 0);
2038 completed_address = TRUE; /* NOW we can set this flag */
2039 if ((log_extra_selector & LX_smtp_confirmation) != 0)
2041 uschar *s = string_printing(buffer);
2042 conf = (s == buffer)? (uschar *)string_copy(s) : s;
2046 /* SMTP, or success return from LMTP for this address. Pass back the
2047 actual host that was used. */
2049 addr->transport_return = OK;
2050 addr->more_errno = delivery_time;
2051 addr->host_used = thost;
2052 addr->special_action = flag;
2053 addr->message = conf;
2054 #ifdef EXPERIMENTAL_PRDR
2055 if (prdr_active) addr->flags |= af_prdr_used;
2059 #ifdef EXPERIMENTAL_PRDR
2063 /* Update the journal. For homonymic addresses, use the base address plus
2064 the transport name. See lots of comments in deliver.c about the reasons
2065 for the complications when homonyms are involved. Just carry on after
2066 write error, as it may prove possible to update the spool file later. */
2068 if (testflag(addr, af_homonym))
2069 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2071 sprintf(CS buffer, "%.500s\n", addr->unique);
2073 DEBUG(D_deliver) debug_printf("journalling %s", buffer);
2074 len = Ustrlen(CS buffer);
2075 if (write(journal_fd, buffer, len) != len)
2076 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2077 "%s: %s", buffer, strerror(errno));
2081 #ifdef EXPERIMENTAL_PRDR
2084 /* PRDR - get the final, overall response. For any non-success
2085 upgrade all the address statuses. */
2086 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2090 if(errno == 0 && buffer[0] == '4')
2092 errno = ERRNO_DATA4XX;
2093 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2095 for (addr = addrlist; addr != first_addr; addr = addr->next)
2096 if (buffer[0] == '5' || addr->transport_return == OK)
2097 addr->transport_return = PENDING_OK; /* allow set_errno action */
2098 goto RESPONSE_FAILED;
2101 /* Update the journal, or setup retry. */
2102 for (addr = addrlist; addr != first_addr; addr = addr->next)
2103 if (addr->transport_return == OK)
2105 if (testflag(addr, af_homonym))
2106 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2108 sprintf(CS buffer, "%.500s\n", addr->unique);
2110 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s", buffer);
2111 len = Ustrlen(CS buffer);
2112 if (write(journal_fd, buffer, len) != len)
2113 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2114 "%s: %s", buffer, strerror(errno));
2116 else if (addr->transport_return == DEFER)
2117 retry_add_item(addr, addr->address_retry_key, -2);
2121 /* Ensure the journal file is pushed out to disk. */
2123 if (EXIMfsync(journal_fd) < 0)
2124 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
2130 /* Handle general (not specific to one address) failures here. The value of ok
2131 is used to skip over this code on the falling through case. A timeout causes a
2132 deferral. Other errors may defer or fail according to the response code, and
2133 may set up a special errno value, e.g. after connection chopped, which is
2134 assumed if errno == 0 and there is no text in the buffer. If control reaches
2135 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
2136 the problem is not related to this specific message. */
2145 send_quit = check_response(host, &save_errno, addrlist->more_errno,
2146 buffer, &code, &message, &pass_message);
2152 message = US string_sprintf("send() to %s [%s] failed: %s",
2153 host->name, host->address, strerror(save_errno));
2157 /* This label is jumped to directly when a TLS negotiation has failed,
2158 or was not done for a host for which it is required. Values will be set
2159 in message and save_errno, and setting_up will always be true. Treat as
2160 a temporary error. */
2167 /* If the failure happened while setting up the call, see if the failure was
2168 a 5xx response (this will either be on connection, or following HELO - a 5xx
2169 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
2170 never going to accept them. For other errors during setting up (timeouts or
2171 whatever), defer all addresses, and yield DEFER, so that the host is not
2172 tried again for a while. */
2175 ok = FALSE; /* For when reached by GOTO */
2181 set_errno(addrlist, save_errno, message, FAIL, pass_message);
2185 set_errno(addrlist, save_errno, message, DEFER, pass_message);
2190 /* We want to handle timeouts after MAIL or "." and loss of connection after
2191 "." specially. They can indicate a problem with the sender address or with
2192 the contents of the message rather than a real error on the connection. These
2193 cases are treated in the same way as a 4xx response. This next bit of code
2194 does the classification. */
2205 message_error = TRUE;
2209 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
2210 Ustrncmp(smtp_command,"end ",4) == 0;
2213 case ERRNO_SMTPCLOSED:
2214 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
2218 message_error = FALSE;
2222 /* Handle the cases that are treated as message errors. These are:
2224 (a) negative response or timeout after MAIL
2225 (b) negative response after DATA
2226 (c) negative response or timeout or dropped connection after "."
2228 It won't be a negative response or timeout after RCPT, as that is dealt
2229 with separately above. The action in all cases is to set an appropriate
2230 error code for all the addresses, but to leave yield set to OK because the
2231 host itself has not failed. Of course, it might in practice have failed
2232 when we've had a timeout, but if so, we'll discover that at the next
2233 delivery attempt. For a temporary error, set the message_defer flag, and
2234 write to the logs for information if this is not the last host. The error
2235 for the last host will be logged as part of the address's log line. */
2239 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
2240 set_errno(addrlist, save_errno, message, (code == '5')? FAIL : DEFER,
2243 /* If there's an errno, the message contains just the identity of
2246 if (code != '5') /* Anything other than 5 is treated as temporary */
2249 message = US string_sprintf("%s: %s", message, strerror(save_errno));
2250 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
2251 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
2252 *message_defer = TRUE;
2256 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
2257 ".", or some other transportation error. We defer all addresses and yield
2258 DEFER, except for the case of failed add_headers expansion, or a transport
2259 filter failure, when the yield should be ERROR, to stop it trying other
2264 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
2265 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
2266 set_errno(addrlist, save_errno, message, DEFER, pass_message);
2272 /* If all has gone well, send_quit will be set TRUE, implying we can end the
2273 SMTP session tidily. However, if there were too many addresses to send in one
2274 message (indicated by first_addr being non-NULL) we want to carry on with the
2275 rest of them. Also, it is desirable to send more than one message down the SMTP
2276 connection if there are several waiting, provided we haven't already sent so
2277 many as to hit the configured limit. The function transport_check_waiting looks
2278 for a waiting message and returns its id. Then transport_pass_socket tries to
2279 set up a continued delivery by passing the socket on to another process. The
2280 variable send_rset is FALSE if a message has just been successfully transfered.
2282 If we are already sending down a continued channel, there may be further
2283 addresses not yet delivered that are aimed at the same host, but which have not
2284 been passed in this run of the transport. In this case, continue_more will be
2285 true, and all we should do is send RSET if necessary, and return, leaving the
2288 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
2289 do not want to continue with other messages down the same channel, because that
2290 can lead to looping between two or more messages, all with the same,
2291 temporarily failing address(es). [The retry information isn't updated yet, so
2292 new processes keep on trying.] We probably also don't want to try more of this
2293 message's addresses either.
2295 If we have started a TLS session, we have to end it before passing the
2296 connection to a new process. However, not all servers can handle this (Exim
2297 can), so we do not pass such a connection on if the host matches
2298 hosts_nopass_tls. */
2301 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
2302 "yield=%d first_address is %sNULL\n", ok, send_quit, send_rset,
2303 continue_more, yield, (first_addr == NULL)? "":"not ");
2305 if (completed_address && ok && send_quit)
2308 if (first_addr != NULL || continue_more ||
2310 (tls_out.active < 0 ||
2311 verify_check_this_host(&(ob->hosts_nopass_tls), NULL, host->name,
2312 host->address, NULL) != OK)
2314 transport_check_waiting(tblock->name, host->name,
2315 tblock->connection_max_messages, new_message_id, &more)
2323 if (! (ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
2325 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
2326 host->address, strerror(save_errno));
2329 else if (! (ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2330 ob->command_timeout)))
2333 send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
2337 DEBUG(D_transport) debug_printf("%s\n", msg);
2342 /* Either RSET was not needed, or it succeeded */
2346 if (first_addr != NULL) /* More addresses still to be sent */
2347 { /* in this run of the transport */
2348 continue_sequence++; /* Causes * in logging */
2351 if (continue_more) return yield; /* More addresses for another run */
2353 /* Pass the socket to a new Exim process. Before doing so, we must shut
2354 down TLS. Not all MTAs allow for the continuation of the SMTP session
2355 when TLS is shut down. We test for this by sending a new EHLO. If we
2356 don't get a good response, we don't attempt to pass the socket on. */
2359 if (tls_out.active >= 0)
2361 tls_close(FALSE, TRUE);
2365 ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
2366 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2367 ob->command_timeout);
2371 /* If the socket is successfully passed, we musn't send QUIT (or
2372 indeed anything!) from here. */
2374 if (ok && transport_pass_socket(tblock->name, host->name, host->address,
2375 new_message_id, inblock.sock))
2381 /* If RSET failed and there are addresses left, they get deferred. */
2383 else set_errno(first_addr, errno, msg, DEFER, FALSE);
2387 /* End off tidily with QUIT unless the connection has died or the socket has
2388 been passed to another process. There has been discussion on the net about what
2389 to do after sending QUIT. The wording of the RFC suggests that it is necessary
2390 to wait for a response, but on the other hand, there isn't anything one can do
2391 with an error response, other than log it. Exim used to do that. However,
2392 further discussion suggested that it is positively advantageous not to wait for
2393 the response, but to close the session immediately. This is supposed to move
2394 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
2395 load from the server. (Hosts that are both servers and clients may not see much
2396 difference, of course.) Further discussion indicated that this was safe to do
2397 on Unix systems which have decent implementations of TCP/IP that leave the
2398 connection around for a while (TIME_WAIT) after the application has gone away.
2399 This enables the response sent by the server to be properly ACKed rather than
2400 timed out, as can happen on broken TCP/IP implementations on other OS.
2402 This change is being made on 31-Jul-98. After over a year of trouble-free
2403 operation, the old commented-out code was removed on 17-Sep-99. */
2406 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2411 tls_close(FALSE, TRUE);
2414 /* Close the socket, and return the appropriate value, first setting
2415 continue_transport and continue_hostname NULL to prevent any other addresses
2416 that may include the host from trying to re-use a continuation socket. This
2417 works because the NULL setting is passed back to the calling process, and
2418 remote_max_parallel is forced to 1 when delivering over an existing connection,
2420 If all went well and continue_more is set, we shouldn't actually get here if
2421 there are further addresses, as the return above will be taken. However,
2422 writing RSET might have failed, or there may be other addresses whose hosts are
2423 specified in the transports, and therefore not visible at top level, in which
2424 case continue_more won't get set. */
2426 (void)close(inblock.sock);
2427 continue_transport = NULL;
2428 continue_hostname = NULL;
2435 /*************************************************
2436 * Closedown entry point *
2437 *************************************************/
2439 /* This function is called when exim is passed an open smtp channel
2440 from another incarnation, but the message which it has been asked
2441 to deliver no longer exists. The channel is on stdin.
2443 We might do fancy things like looking for another message to send down
2444 the channel, but if the one we sought has gone, it has probably been
2445 delivered by some other process that itself will seek further messages,
2446 so just close down our connection.
2448 Argument: pointer to the transport instance block
2453 smtp_transport_closedown(transport_instance *tblock)
2455 smtp_transport_options_block *ob =
2456 (smtp_transport_options_block *)(tblock->options_block);
2457 smtp_inblock inblock;
2458 smtp_outblock outblock;
2460 uschar inbuffer[4096];
2461 uschar outbuffer[16];
2463 inblock.sock = fileno(stdin);
2464 inblock.buffer = inbuffer;
2465 inblock.buffersize = sizeof(inbuffer);
2466 inblock.ptr = inbuffer;
2467 inblock.ptrend = inbuffer;
2469 outblock.sock = inblock.sock;
2470 outblock.buffersize = sizeof(outbuffer);
2471 outblock.buffer = outbuffer;
2472 outblock.ptr = outbuffer;
2473 outblock.cmd_count = 0;
2474 outblock.authenticating = FALSE;
2476 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2477 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2478 ob->command_timeout);
2479 (void)close(inblock.sock);
2484 /*************************************************
2485 * Prepare addresses for delivery *
2486 *************************************************/
2488 /* This function is called to flush out error settings from previous delivery
2489 attempts to other hosts. It also records whether we got here via an MX record
2490 or not in the more_errno field of the address. We are interested only in
2491 addresses that are still marked DEFER - others may have got delivered to a
2492 previously considered IP address. Set their status to PENDING_DEFER to indicate
2493 which ones are relevant this time.
2496 addrlist the list of addresses
2497 host the host we are delivering to
2499 Returns: the first address for this delivery
2502 static address_item *
2503 prepare_addresses(address_item *addrlist, host_item *host)
2505 address_item *first_addr = NULL;
2507 for (addr = addrlist; addr != NULL; addr = addr->next)
2509 if (addr->transport_return != DEFER) continue;
2510 if (first_addr == NULL) first_addr = addr;
2511 addr->transport_return = PENDING_DEFER;
2512 addr->basic_errno = 0;
2513 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
2514 addr->message = NULL;
2516 addr->cipher = NULL;
2517 addr->peerdn = NULL;
2525 /*************************************************
2526 * Main entry point *
2527 *************************************************/
2529 /* See local README for interface details. As this is a remote transport, it is
2530 given a chain of addresses to be delivered in one connection, if possible. It
2531 always returns TRUE, indicating that each address has its own independent
2532 status set, except if there is a setting up problem, in which case it returns
2536 smtp_transport_entry(
2537 transport_instance *tblock, /* data for this instantiation */
2538 address_item *addrlist) /* addresses we are working on */
2542 int hosts_defer = 0;
2544 int hosts_looked_up = 0;
2545 int hosts_retry = 0;
2546 int hosts_serial = 0;
2547 int hosts_total = 0;
2548 int total_hosts_tried = 0;
2550 BOOL expired = TRUE;
2551 BOOL continuing = continue_hostname != NULL;
2552 uschar *expanded_hosts = NULL;
2554 uschar *tid = string_sprintf("%s transport", tblock->name);
2555 smtp_transport_options_block *ob =
2556 (smtp_transport_options_block *)(tblock->options_block);
2557 host_item *hostlist = addrlist->host_list;
2558 host_item *host = NULL;
2562 debug_printf("%s transport entered\n", tblock->name);
2563 for (addr = addrlist; addr != NULL; addr = addr->next)
2564 debug_printf(" %s\n", addr->address);
2565 if (continuing) debug_printf("already connected to %s [%s]\n",
2566 continue_hostname, continue_host_address);
2569 /* Set the flag requesting that these hosts be added to the waiting
2570 database if the delivery fails temporarily or if we are running with
2571 queue_smtp or a 2-stage queue run. This gets unset for certain
2572 kinds of error, typically those that are specific to the message. */
2574 update_waiting = TRUE;
2576 /* If a host list is not defined for the addresses - they must all have the
2577 same one in order to be passed to a single transport - or if the transport has
2578 a host list with hosts_override set, use the host list supplied with the
2579 transport. It is an error for this not to exist. */
2581 if (hostlist == NULL || (ob->hosts_override && ob->hosts != NULL))
2583 if (ob->hosts == NULL)
2585 addrlist->message = string_sprintf("%s transport called with no hosts set",
2587 addrlist->transport_return = PANIC;
2588 return FALSE; /* Only top address has status */
2591 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
2594 /* If the transport's host list contains no '$' characters, and we are not
2595 randomizing, it is fixed and therefore a chain of hosts can be built once
2596 and for all, and remembered for subsequent use by other calls to this
2597 transport. If, on the other hand, the host list does contain '$', or we are
2598 randomizing its order, we have to rebuild it each time. In the fixed case,
2599 as the hosts string will never be used again, it doesn't matter that we
2600 replace all the : characters with zeros. */
2602 if (ob->hostlist == NULL)
2604 uschar *s = ob->hosts;
2606 if (Ustrchr(s, '$') != NULL)
2608 expanded_hosts = expand_string(s);
2609 if (expanded_hosts == NULL)
2611 addrlist->message = string_sprintf("failed to expand list of hosts "
2612 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
2613 addrlist->transport_return = search_find_defer? DEFER : PANIC;
2614 return FALSE; /* Only top address has status */
2616 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
2617 "\"%s\"\n", s, expanded_hosts);
2621 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
2623 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
2625 /* Check that the expansion yielded something useful. */
2626 if (hostlist == NULL)
2629 string_sprintf("%s transport has empty hosts setting", tblock->name);
2630 addrlist->transport_return = PANIC;
2631 return FALSE; /* Only top address has status */
2634 /* If there was no expansion of hosts, save the host list for
2637 if (expanded_hosts == NULL) ob->hostlist = hostlist;
2640 /* This is not the first time this transport has been run in this delivery;
2641 the host list was built previously. */
2643 else hostlist = ob->hostlist;
2646 /* The host list was supplied with the address. If hosts_randomize is set, we
2647 must sort it into a random order if it did not come from MX records and has not
2648 already been randomized (but don't bother if continuing down an existing
2651 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continuing)
2653 host_item *newlist = NULL;
2654 while (hostlist != NULL)
2656 host_item *h = hostlist;
2657 hostlist = hostlist->next;
2659 h->sort_key = random_number(100);
2661 if (newlist == NULL)
2666 else if (h->sort_key < newlist->sort_key)
2673 host_item *hh = newlist;
2674 while (hh->next != NULL)
2676 if (h->sort_key < hh->next->sort_key) break;
2684 hostlist = addrlist->host_list = newlist;
2688 /* Sort out the default port. */
2690 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
2693 /* For each host-plus-IP-address on the list:
2695 . If this is a continued delivery and the host isn't the one with the
2696 current connection, skip.
2698 . If the status is unusable (i.e. previously failed or retry checked), skip.
2700 . If no IP address set, get the address, either by turning the name into
2701 an address, calling gethostbyname if gethostbyname is on, or by calling
2702 the DNS. The DNS may yield multiple addresses, in which case insert the
2703 extra ones into the list.
2705 . Get the retry data if not previously obtained for this address and set the
2706 field which remembers the state of this address. Skip if the retry time is
2707 not reached. If not, remember whether retry data was found. The retry string
2708 contains both the name and the IP address.
2710 . Scan the list of addresses and mark those whose status is DEFER as
2711 PENDING_DEFER. These are the only ones that will be processed in this cycle
2714 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
2715 Some addresses may be successfully delivered, others may fail, and yet
2716 others may get temporary errors and so get marked DEFER.
2718 . The return from the delivery attempt is OK if a connection was made and a
2719 valid SMTP dialogue was completed. Otherwise it is DEFER.
2721 . If OK, add a "remove" retry item for this host/IPaddress, if any.
2723 . If fail to connect, or other defer state, add a retry item.
2725 . If there are any addresses whose status is still DEFER, carry on to the
2726 next host/IPaddress, unless we have tried the number of hosts given
2727 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
2728 there is some fancy logic for hosts_max_try that means its limit can be
2729 overstepped in some circumstances.
2731 If we get to the end of the list, all hosts have deferred at least one address,
2732 or not reached their retry times. If delay_after_cutoff is unset, it requests a
2733 delivery attempt to those hosts whose last try was before the arrival time of
2734 the current message. To cope with this, we have to go round the loop a second
2735 time. After that, set the status and error data for any addresses that haven't
2736 had it set already. */
2738 for (cutoff_retry = 0; expired &&
2739 cutoff_retry < ((ob->delay_after_cutoff)? 1 : 2);
2742 host_item *nexthost = NULL;
2743 int unexpired_hosts_tried = 0;
2745 for (host = hostlist;
2747 unexpired_hosts_tried < ob->hosts_max_try &&
2748 total_hosts_tried < ob->hosts_max_try_hardlimit;
2754 BOOL serialized = FALSE;
2755 BOOL host_is_expired = FALSE;
2756 BOOL message_defer = FALSE;
2757 BOOL ifchanges = FALSE;
2758 BOOL some_deferred = FALSE;
2759 address_item *first_addr = NULL;
2760 uschar *interface = NULL;
2761 uschar *retry_host_key = NULL;
2762 uschar *retry_message_key = NULL;
2763 uschar *serialize_key = NULL;
2765 /* Default next host is next host. :-) But this can vary if the
2766 hosts_max_try limit is hit (see below). It may also be reset if a host
2767 address is looked up here (in case the host was multihomed). */
2769 nexthost = host->next;
2771 /* If the address hasn't yet been obtained from the host name, look it up
2772 now, unless the host is already marked as unusable. If it is marked as
2773 unusable, it means that the router was unable to find its IP address (in
2774 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
2775 the lookup failed last time. We don't get this far if *all* MX records
2776 point to non-existent hosts; that is treated as a hard error.
2778 We can just skip this host entirely. When the hosts came from the router,
2779 the address will timeout based on the other host(s); when the address is
2780 looked up below, there is an explicit retry record added.
2782 Note that we mustn't skip unusable hosts if the address is not unset; they
2783 may be needed as expired hosts on the 2nd time round the cutoff loop. */
2785 if (host->address == NULL)
2787 int new_port, flags;
2789 uschar *canonical_name;
2791 if (host->status >= hstatus_unusable)
2793 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
2798 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
2800 /* The host name is permitted to have an attached port. Find it, and
2801 strip it from the name. Just remember it for now. */
2803 new_port = host_item_get_port(host);
2805 /* Count hosts looked up */
2809 /* Find by name if so configured, or if it's an IP address. We don't
2810 just copy the IP address, because we need the test-for-local to happen. */
2812 flags = HOST_FIND_BY_A;
2813 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
2814 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
2816 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
2817 rc = host_find_byname(host, NULL, flags, &canonical_name, TRUE);
2819 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
2820 &canonical_name, NULL);
2822 /* Update the host (and any additional blocks, resulting from
2823 multihoming) with a host-specific port, if any. */
2825 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
2827 /* Failure to find the host at this time (usually DNS temporary failure)
2828 is really a kind of routing failure rather than a transport failure.
2829 Therefore we add a retry item of the routing kind, not to stop us trying
2830 to look this name up here again, but to ensure the address gets timed
2831 out if the failures go on long enough. A complete failure at this point
2832 commonly points to a configuration error, but the best action is still
2833 to carry on for the next host. */
2835 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
2837 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
2839 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
2840 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
2841 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
2842 host->status = hstatus_unusable;
2844 for (addr = addrlist; addr != NULL; addr = addr->next)
2846 if (addr->transport_return != DEFER) continue;
2847 addr->basic_errno = ERRNO_UNKNOWNHOST;
2849 string_sprintf("failed to lookup IP address for %s", host->name);
2854 /* If the host is actually the local host, we may have a problem, or
2855 there may be some cunning configuration going on. In the problem case,
2856 log things and give up. The default transport status is already DEFER. */
2858 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
2860 for (addr = addrlist; addr != NULL; addr = addr->next)
2862 addr->basic_errno = 0;
2863 addr->message = string_sprintf("%s transport found host %s to be "
2864 "local", tblock->name, host->name);
2868 } /* End of block for IP address lookup */
2870 /* If this is a continued delivery, we are interested only in the host
2871 which matches the name of the existing open channel. The check is put
2872 here after the local host lookup, in case the name gets expanded as a
2873 result of the lookup. Set expired FALSE, to save the outer loop executing
2876 if (continuing && (Ustrcmp(continue_hostname, host->name) != 0 ||
2877 Ustrcmp(continue_host_address, host->address) != 0))
2880 continue; /* With next host */
2883 /* Reset the default next host in case a multihomed host whose addresses
2884 are not looked up till just above added to the host list. */
2886 nexthost = host->next;
2888 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
2889 domain is in queue_smtp_domains, we don't actually want to attempt any
2890 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
2891 there is a lookup defer in queue_smtp_domains, proceed as if the domain
2892 were not in it. We don't want to hold up all SMTP deliveries! Except when
2893 doing a two-stage queue run, don't do this if forcing. */
2895 if ((!deliver_force || queue_2stage) && (queue_smtp ||
2896 match_isinlist(addrlist->domain, &queue_smtp_domains, 0,
2897 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
2900 for (addr = addrlist; addr != NULL; addr = addr->next)
2902 if (addr->transport_return != DEFER) continue;
2903 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
2905 continue; /* With next host */
2908 /* Count hosts being considered - purely for an intelligent comment
2909 if none are usable. */
2913 /* Set $host and $host address now in case they are needed for the
2914 interface expansion or the serialize_hosts check; they remain set if an
2915 actual delivery happens. */
2917 deliver_host = host->name;
2918 deliver_host_address = host->address;
2920 /* Set up a string for adding to the retry key if the port number is not
2921 the standard SMTP port. A host may have its own port setting that overrides
2924 pistring = string_sprintf(":%d", (host->port == PORT_NONE)?
2926 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
2928 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
2929 string changes upon expansion, we must add it to the key that is used for
2930 retries, because connections to the same host from a different interface
2931 should be treated separately. */
2933 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET : AF_INET6;
2934 if (!smtp_get_interface(ob->interface, host_af, addrlist, &ifchanges,
2937 if (ifchanges) pistring = string_sprintf("%s/%s", pistring, interface);
2939 /* The first time round the outer loop, check the status of the host by
2940 inspecting the retry data. The second time round, we are interested only
2941 in expired hosts that haven't been tried since this message arrived. */
2943 if (cutoff_retry == 0)
2945 /* Ensure the status of the address is set by checking retry data if
2946 necessary. There maybe host-specific retry data (applicable to all
2947 messages) and also data for retries of a specific message at this host.
2948 If either of these retry records are actually read, the keys used are
2949 returned to save recomputing them later. */
2951 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
2952 ob->retry_include_ip_address, &retry_host_key, &retry_message_key);
2954 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
2955 (host->address == NULL)? US"" : host->address, pistring,
2956 (host->status == hstatus_usable)? "usable" :
2957 (host->status == hstatus_unusable)? "unusable" :
2958 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
2960 /* Skip this address if not usable at this time, noting if it wasn't
2961 actually expired, both locally and in the address. */
2963 switch (host->status)
2965 case hstatus_unusable:
2967 setflag(addrlist, af_retry_skipped);
2970 case hstatus_unusable_expired:
2973 case hwhy_retry: hosts_retry++; break;
2974 case hwhy_failed: hosts_fail++; break;
2975 case hwhy_deferred: hosts_defer++; break;
2978 /* If there was a retry message key, implying that previously there
2979 was a message-specific defer, we don't want to update the list of
2980 messages waiting for these hosts. */
2982 if (retry_message_key != NULL) update_waiting = FALSE;
2983 continue; /* With the next host or IP address */
2987 /* Second time round the loop: if the address is set but expired, and
2988 the message is newer than the last try, let it through. */
2992 if (host->address == NULL ||
2993 host->status != hstatus_unusable_expired ||
2994 host->last_try > received_time)
2997 debug_printf("trying expired host %s [%s]%s\n",
2998 host->name, host->address, pistring);
2999 host_is_expired = TRUE;
3002 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
3003 it remains TRUE only if all hosts are expired and none are actually tried.
3008 /* If this host is listed as one to which access must be serialized,
3009 see if another Exim process has a connection to it, and if so, skip
3010 this host. If not, update the database to record our connection to it
3011 and remember this for later deletion. Do not do any of this if we are
3012 sending the message down a pre-existing connection. */
3015 verify_check_this_host(&(ob->serialize_hosts), NULL, host->name,
3016 host->address, NULL) == OK)
3018 serialize_key = string_sprintf("host-serialize-%s", host->name);
3019 if (!enq_start(serialize_key))
3022 debug_printf("skipping host %s because another Exim process "
3023 "is connected to it\n", host->name);
3030 /* OK, we have an IP address that is not waiting for its retry time to
3031 arrive (it might be expired) OR (second time round the loop) we have an
3032 expired host that hasn't been tried since the message arrived. Have a go
3033 at delivering the message to it. First prepare the addresses by flushing
3034 out the result of previous attempts, and finding the first address that
3035 is still to be delivered. */
3037 first_addr = prepare_addresses(addrlist, host);
3039 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
3040 message_id, host->name, host->address, addrlist->address,
3041 (addrlist->next == NULL)? "" : ", ...");
3043 set_process_info("delivering %s to %s [%s] (%s%s)",
3044 message_id, host->name, host->address, addrlist->address,
3045 (addrlist->next == NULL)? "" : ", ...");
3047 /* This is not for real; don't do the delivery. If there are
3048 any remaining hosts, list them. */
3053 set_errno(addrlist, 0, NULL, OK, FALSE);
3054 for (addr = addrlist; addr != NULL; addr = addr->next)
3056 addr->host_used = host;
3057 addr->special_action = '*';
3058 addr->message = US"delivery bypassed by -N option";
3062 debug_printf("*** delivery by %s transport bypassed by -N option\n"
3063 "*** host and remaining hosts:\n", tblock->name);
3064 for (host2 = host; host2 != NULL; host2 = host2->next)
3065 debug_printf(" %s [%s]\n", host2->name,
3066 (host2->address == NULL)? US"unset" : host2->address);
3071 /* This is for real. If the host is expired, we don't count it for
3072 hosts_max_retry. This ensures that all hosts must expire before an address
3073 is timed out, unless hosts_max_try_hardlimit (which protects against
3074 lunatic DNS configurations) is reached.
3076 If the host is not expired and we are about to hit the hosts_max_retry
3077 limit, check to see if there is a subsequent hosts with a different MX
3078 value. If so, make that the next host, and don't count this one. This is a
3079 heuristic to make sure that different MXs do get tried. With a normal kind
3080 of retry rule, they would get tried anyway when the earlier hosts were
3081 delayed, but if the domain has a "retry every time" type of rule - as is
3082 often used for the the very large ISPs, that won't happen. */
3086 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
3090 debug_printf("hosts_max_try limit reached with this host\n");
3091 for (h = host; h != NULL; h = h->next)
3092 if (h->mx != host->mx) break;
3096 unexpired_hosts_tried--;
3097 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
3098 "and will be tried\n");
3102 /* Attempt the delivery. */
3104 total_hosts_tried++;
3105 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
3106 expanded_hosts != NULL, &message_defer, FALSE);
3109 OK => connection made, each address contains its result;
3110 message_defer is set for message-specific defers (when all
3111 recipients are marked defer)
3112 DEFER => there was a non-message-specific delivery problem;
3113 ERROR => there was a problem setting up the arguments for a filter,
3114 or there was a problem with expanding added headers
3117 /* If the result is not OK, there was a non-message-specific problem.
3118 If the result is DEFER, we need to write to the logs saying what happened
3119 for this particular host, except in the case of authentication and TLS
3120 failures, where the log has already been written. If all hosts defer a
3121 general message is written at the end. */
3123 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL &&
3124 first_addr->basic_errno != ERRNO_TLSFAILURE)
3125 write_logs(first_addr, host);
3127 #ifdef EXPERIMENTAL_TPDA
3129 tpda_deferred(ob, first_addr, host);
3132 /* If STARTTLS was accepted, but there was a failure in setting up the
3133 TLS session (usually a certificate screwup), and the host is not in
3134 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
3135 TLS forcibly turned off. We have to start from scratch with a new SMTP
3136 connection. That's why the retry is done from here, not from within
3137 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
3138 session, so the in-clear transmission after those errors, if permitted,
3139 happens inside smtp_deliver().] */
3142 if (rc == DEFER && first_addr->basic_errno == ERRNO_TLSFAILURE &&
3143 ob->tls_tempfail_tryclear &&
3144 verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
3145 host->address, NULL) != OK)
3147 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
3148 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
3149 first_addr = prepare_addresses(addrlist, host);
3150 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
3151 expanded_hosts != NULL, &message_defer, TRUE);
3152 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
3153 write_logs(first_addr, host);
3154 #ifdef EXPERIMENTAL_TPDA
3156 tpda_deferred(ob, first_addr, host);
3162 /* Delivery attempt finished */
3164 rs = (rc == OK)? US"OK" : (rc == DEFER)? US"DEFER" : (rc == ERROR)?
3167 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
3168 message_id, host->name, host->address, addrlist->address,
3169 (addrlist->next == NULL)? "" : " (& others)", rs);
3171 /* Release serialization if set up */
3173 if (serialized) enq_end(serialize_key);
3175 /* If the result is DEFER, or if a host retry record is known to exist, we
3176 need to add an item to the retry chain for updating the retry database
3177 at the end of delivery. We only need to add the item to the top address,
3178 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
3179 for any other delivery attempts using the same address. (It is copied into
3180 the unusable tree at the outer level, so even if different address blocks
3181 contain the same address, it still won't get tried again.) */
3183 if (rc == DEFER || retry_host_key != NULL)
3185 int delete_flag = (rc != DEFER)? rf_delete : 0;
3186 if (retry_host_key == NULL)
3188 retry_host_key = ob->retry_include_ip_address?
3189 string_sprintf("T:%S:%s%s", host->name, host->address, pistring) :
3190 string_sprintf("T:%S%s", host->name, pistring);
3193 /* If a delivery of another message over an existing SMTP connection
3194 yields DEFER, we do NOT set up retry data for the host. This covers the
3195 case when there are delays in routing the addresses in the second message
3196 that are so long that the server times out. This is alleviated by not
3197 routing addresses that previously had routing defers when handling an
3198 existing connection, but even so, this case may occur (e.g. if a
3199 previously happily routed address starts giving routing defers). If the
3200 host is genuinely down, another non-continued message delivery will
3201 notice it soon enough. */
3203 if (delete_flag != 0 || !continuing)
3204 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
3206 /* We may have tried an expired host, if its retry time has come; ensure
3207 the status reflects the expiry for the benefit of any other addresses. */
3211 host->status = (host_is_expired)?
3212 hstatus_unusable_expired : hstatus_unusable;
3213 host->why = hwhy_deferred;
3217 /* If message_defer is set (host was OK, but every recipient got deferred
3218 because of some message-specific problem), or if that had happened
3219 previously so that a message retry key exists, add an appropriate item
3220 to the retry chain. Note that if there was a message defer but now there is
3221 a host defer, the message defer record gets deleted. That seems perfectly
3222 reasonable. Also, stop the message from being remembered as waiting
3223 for specific hosts. */
3225 if (message_defer || retry_message_key != NULL)
3227 int delete_flag = message_defer? 0 : rf_delete;
3228 if (retry_message_key == NULL)
3230 retry_message_key = ob->retry_include_ip_address?
3231 string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
3233 string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
3235 retry_add_item(addrlist, retry_message_key,
3236 rf_message | rf_host | delete_flag);
3237 update_waiting = FALSE;
3240 /* Any return other than DEFER (that is, OK or ERROR) means that the
3241 addresses have got their final statuses filled in for this host. In the OK
3242 case, see if any of them are deferred. */
3246 for (addr = addrlist; addr != NULL; addr = addr->next)
3248 if (addr->transport_return == DEFER)
3250 some_deferred = TRUE;
3256 /* If no addresses deferred or the result was ERROR, return. We do this for
3257 ERROR because a failing filter set-up or add_headers expansion is likely to
3258 fail for any host we try. */
3260 if (rc == ERROR || (rc == OK && !some_deferred))
3262 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3263 return TRUE; /* Each address has its status */
3266 /* If the result was DEFER or some individual addresses deferred, let
3267 the loop run to try other hosts with the deferred addresses, except for the
3268 case when we were trying to deliver down an existing channel and failed.
3269 Don't try any other hosts in this case. */
3271 if (continuing) break;
3273 /* If the whole delivery, or some individual addresses, were deferred and
3274 there are more hosts that could be tried, do not count this host towards
3275 the hosts_max_try limit if the age of the message is greater than the
3276 maximum retry time for this host. This means we may try try all hosts,
3277 ignoring the limit, when messages have been around for some time. This is
3278 important because if we don't try all hosts, the address will never time
3279 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
3281 if ((rc == DEFER || some_deferred) && nexthost != NULL)
3284 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
3286 if (retry != NULL && retry->rules != NULL)
3288 retry_rule *last_rule;
3289 for (last_rule = retry->rules;
3290 last_rule->next != NULL;
3291 last_rule = last_rule->next);
3292 timedout = time(NULL) - received_time > last_rule->timeout;
3294 else timedout = TRUE; /* No rule => timed out */
3298 unexpired_hosts_tried--;
3299 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
3300 "hosts_max_try (message older than host's retry time)\n");
3303 } /* End of loop for trying multiple hosts. */
3305 /* This is the end of the loop that repeats iff expired is TRUE and
3306 ob->delay_after_cutoff is FALSE. The second time round we will
3307 try those hosts that haven't been tried since the message arrived. */
3311 debug_printf("all IP addresses skipped or deferred at least one address\n");
3312 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
3313 debug_printf("retrying IP addresses not tried since message arrived\n");
3318 /* Get here if all IP addresses are skipped or defer at least one address. In
3319 MUA wrapper mode, this will happen only for connection or other non-message-
3320 specific failures. Force the delivery status for all addresses to FAIL. */
3324 for (addr = addrlist; addr != NULL; addr = addr->next)
3325 addr->transport_return = FAIL;
3329 /* In the normal, non-wrapper case, add a standard message to each deferred
3330 address if there hasn't been an error, that is, if it hasn't actually been
3331 tried this time. The variable "expired" will be FALSE if any deliveries were
3332 actually tried, or if there was at least one host that was not expired. That
3333 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
3334 a delivery has been tried, an error code will be set, and the failing of the
3335 message is handled by the retry code later.
3337 If queue_smtp is set, or this transport was called to send a subsequent message
3338 down an existing TCP/IP connection, and something caused the host not to be
3339 found, we end up here, but can detect these cases and handle them specially. */
3341 for (addr = addrlist; addr != NULL; addr = addr->next)
3343 /* If host is not NULL, it means that we stopped processing the host list
3344 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
3345 means we need to behave as if some hosts were skipped because their retry
3346 time had not come. Specifically, this prevents the address from timing out.
3347 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
3348 hosts were tried. */
3352 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
3355 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
3356 "hosts were tried\n");
3361 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
3362 setflag(addr, af_retry_skipped);
3366 if (queue_smtp) /* no deliveries attempted */
3368 addr->transport_return = DEFER;
3369 addr->basic_errno = 0;
3370 addr->message = US"SMTP delivery explicitly queued";
3373 else if (addr->transport_return == DEFER &&
3374 (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0) &&
3375 addr->message == NULL)
3377 addr->basic_errno = ERRNO_HRETRY;
3378 if (continue_hostname != NULL)
3380 addr->message = US"no host found for existing SMTP connection";
3384 setflag(addr, af_pass_message); /* This is not a security risk */
3385 addr->message = (ob->delay_after_cutoff)?
3386 US"retry time not reached for any host after a long failure period" :
3387 US"all hosts have been failing for a long time and were last tried "
3388 "after this message arrived";
3390 /* If we are already using fallback hosts, or there are no fallback hosts
3391 defined, convert the result to FAIL to cause a bounce. */
3393 if (addr->host_list == addr->fallback_hosts ||
3394 addr->fallback_hosts == NULL)
3395 addr->transport_return = FAIL;
3399 if (hosts_retry == hosts_total)
3400 addr->message = US"retry time not reached for any host";
3401 else if (hosts_fail == hosts_total)
3402 addr->message = US"all host address lookups failed permanently";
3403 else if (hosts_defer == hosts_total)
3404 addr->message = US"all host address lookups failed temporarily";
3405 else if (hosts_serial == hosts_total)
3406 addr->message = US"connection limit reached for all hosts";
3407 else if (hosts_fail+hosts_defer == hosts_total)
3408 addr->message = US"all host address lookups failed";
3409 else addr->message = US"some host address lookups failed and retry time "
3410 "not reached for other hosts or connection limit reached";
3415 /* Update the database which keeps information about which messages are waiting
3416 for which hosts to become available. For some message-specific errors, the
3417 update_waiting flag is turned off because we don't want follow-on deliveries in
3418 those cases. If this transport instance is explicitly limited to one message
3419 per connection then follow-on deliveries are not possible and there's no need
3420 to create/update the per-transport wait-<transport_name> database. */
3422 if (update_waiting && tblock->connection_max_messages != 1)
3423 transport_update_waiting(hostlist, tblock->name);
3427 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3429 return TRUE; /* Each address has its status */
3432 /* End of transport/smtp.c */
git://git.exim.org / exim.git / blob