1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2012 */
6 /* See the file NOTICE for conditions of use and distribution. */
12 #define PENDING_DEFER (PENDING + DEFER)
13 #define PENDING_OK (PENDING + OK)
16 /* Options specific to the smtp transport. This transport also supports LMTP
17 over TCP/IP. The options must be in alphabetic order (note that "_" comes
18 before the lower case letters). Some live in the transport_instance block so as
19 to be publicly visible; these are flagged with opt_public. */
21 optionlist smtp_transport_options[] = {
22 { "address_retry_include_sender", opt_bool,
23 (void *)offsetof(smtp_transport_options_block, address_retry_include_sender) },
24 { "allow_localhost", opt_bool,
25 (void *)offsetof(smtp_transport_options_block, allow_localhost) },
26 { "authenticated_sender", opt_stringptr,
27 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
28 { "authenticated_sender_force", opt_bool,
29 (void *)offsetof(smtp_transport_options_block, authenticated_sender_force) },
30 { "command_timeout", opt_time,
31 (void *)offsetof(smtp_transport_options_block, command_timeout) },
32 { "connect_timeout", opt_time,
33 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
34 { "connection_max_messages", opt_int | opt_public,
35 (void *)offsetof(transport_instance, connection_max_messages) },
36 { "data_timeout", opt_time,
37 (void *)offsetof(smtp_transport_options_block, data_timeout) },
38 #ifdef EXPERIMENTAL_DBL
39 { "dbl_host_defer_query", opt_stringptr,
40 (void *)offsetof(smtp_transport_options_block, dbl_host_defer_query) },
42 { "delay_after_cutoff", opt_bool,
43 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
45 { "dkim_canon", opt_stringptr,
46 (void *)offsetof(smtp_transport_options_block, dkim_canon) },
47 { "dkim_domain", opt_stringptr,
48 (void *)offsetof(smtp_transport_options_block, dkim_domain) },
49 { "dkim_private_key", opt_stringptr,
50 (void *)offsetof(smtp_transport_options_block, dkim_private_key) },
51 { "dkim_selector", opt_stringptr,
52 (void *)offsetof(smtp_transport_options_block, dkim_selector) },
53 { "dkim_sign_headers", opt_stringptr,
54 (void *)offsetof(smtp_transport_options_block, dkim_sign_headers) },
55 { "dkim_strict", opt_stringptr,
56 (void *)offsetof(smtp_transport_options_block, dkim_strict) },
58 { "dns_qualify_single", opt_bool,
59 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
60 { "dns_search_parents", opt_bool,
61 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
62 { "fallback_hosts", opt_stringptr,
63 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
64 { "final_timeout", opt_time,
65 (void *)offsetof(smtp_transport_options_block, final_timeout) },
66 { "gethostbyname", opt_bool,
67 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
69 /* These are no longer honoured, as of Exim 4.80; for now, we silently
70 ignore; a later release will warn, and a later-still release will remove
71 these options, so that using them becomes an error. */
72 { "gnutls_require_kx", opt_stringptr,
73 (void *)offsetof(smtp_transport_options_block, gnutls_require_kx) },
74 { "gnutls_require_mac", opt_stringptr,
75 (void *)offsetof(smtp_transport_options_block, gnutls_require_mac) },
76 { "gnutls_require_protocols", opt_stringptr,
77 (void *)offsetof(smtp_transport_options_block, gnutls_require_proto) },
79 { "helo_data", opt_stringptr,
80 (void *)offsetof(smtp_transport_options_block, helo_data) },
81 { "hosts", opt_stringptr,
82 (void *)offsetof(smtp_transport_options_block, hosts) },
83 { "hosts_avoid_esmtp", opt_stringptr,
84 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
85 { "hosts_avoid_pipelining", opt_stringptr,
86 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
88 { "hosts_avoid_tls", opt_stringptr,
89 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
91 { "hosts_max_try", opt_int,
92 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
93 { "hosts_max_try_hardlimit", opt_int,
94 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
96 { "hosts_nopass_tls", opt_stringptr,
97 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
99 { "hosts_override", opt_bool,
100 (void *)offsetof(smtp_transport_options_block, hosts_override) },
101 { "hosts_randomize", opt_bool,
102 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
103 { "hosts_require_auth", opt_stringptr,
104 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
106 { "hosts_require_tls", opt_stringptr,
107 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
109 { "hosts_try_auth", opt_stringptr,
110 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
111 { "interface", opt_stringptr,
112 (void *)offsetof(smtp_transport_options_block, interface) },
113 { "keepalive", opt_bool,
114 (void *)offsetof(smtp_transport_options_block, keepalive) },
115 { "lmtp_ignore_quota", opt_bool,
116 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
117 { "max_rcpt", opt_int | opt_public,
118 (void *)offsetof(transport_instance, max_addresses) },
119 { "multi_domain", opt_bool | opt_public,
120 (void *)offsetof(transport_instance, multi_domain) },
121 { "port", opt_stringptr,
122 (void *)offsetof(smtp_transport_options_block, port) },
123 { "protocol", opt_stringptr,
124 (void *)offsetof(smtp_transport_options_block, protocol) },
125 { "retry_include_ip_address", opt_bool,
126 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
127 { "serialize_hosts", opt_stringptr,
128 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
129 { "size_addition", opt_int,
130 (void *)offsetof(smtp_transport_options_block, size_addition) }
132 ,{ "tls_certificate", opt_stringptr,
133 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
134 { "tls_crl", opt_stringptr,
135 (void *)offsetof(smtp_transport_options_block, tls_crl) },
136 { "tls_privatekey", opt_stringptr,
137 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
138 { "tls_require_ciphers", opt_stringptr,
139 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
140 { "tls_sni", opt_stringptr,
141 (void *)offsetof(smtp_transport_options_block, tls_sni) },
142 { "tls_tempfail_tryclear", opt_bool,
143 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
144 { "tls_verify_certificates", opt_stringptr,
145 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) }
149 /* Size of the options list. An extern variable has to be used so that its
150 address can appear in the tables drtables.c. */
152 int smtp_transport_options_count =
153 sizeof(smtp_transport_options)/sizeof(optionlist);
155 /* Default private options block for the smtp transport. */
157 smtp_transport_options_block smtp_transport_option_defaults = {
159 NULL, /* fallback_hosts */
161 NULL, /* fallback_hostlist */
162 NULL, /* authenticated_sender */
163 US"$primary_hostname", /* helo_data */
164 NULL, /* interface */
166 US"smtp", /* protocol */
167 NULL, /* serialize_hosts */
168 NULL, /* hosts_try_auth */
169 NULL, /* hosts_require_auth */
170 NULL, /* hosts_require_tls */
171 NULL, /* hosts_avoid_tls */
172 NULL, /* hosts_avoid_pipelining */
173 NULL, /* hosts_avoid_esmtp */
174 NULL, /* hosts_nopass_tls */
175 5*60, /* command_timeout */
176 5*60, /* connect_timeout; shorter system default overrides */
177 5*60, /* data timeout */
178 10*60, /* final timeout */
179 1024, /* size_addition */
180 5, /* hosts_max_try */
181 50, /* hosts_max_try_hardlimit */
182 TRUE, /* address_retry_include_sender */
183 FALSE, /* allow_localhost */
184 FALSE, /* authenticated_sender_force */
185 FALSE, /* gethostbyname */
186 TRUE, /* dns_qualify_single */
187 FALSE, /* dns_search_parents */
188 TRUE, /* delay_after_cutoff */
189 FALSE, /* hosts_override */
190 FALSE, /* hosts_randomize */
191 TRUE, /* keepalive */
192 FALSE, /* lmtp_ignore_quota */
193 TRUE /* retry_include_ip_address */
195 ,NULL, /* tls_certificate */
197 NULL, /* tls_privatekey */
198 NULL, /* tls_require_ciphers */
199 NULL, /* gnutls_require_kx */
200 NULL, /* gnutls_require_mac */
201 NULL, /* gnutls_require_proto */
202 NULL, /* tls_verify_certificates */
203 TRUE, /* tls_tempfail_tryclear */
207 ,NULL, /* dkim_canon */
208 NULL, /* dkim_domain */
209 NULL, /* dkim_private_key */
210 NULL, /* dkim_selector */
211 NULL, /* dkim_sign_headers */
212 NULL /* dkim_strict */
214 #ifdef EXPERIMENTAL_DBL
215 ,NULL /* dbl_host_defer_query */
222 static uschar *smtp_command; /* Points to last cmd for error messages */
223 static uschar *mail_command; /* Points to MAIL cmd for error messages */
224 static BOOL update_waiting; /* TRUE to update the "wait" database */
227 /*************************************************
228 * Setup entry point *
229 *************************************************/
231 /* This function is called when the transport is about to be used,
232 but before running it in a sub-process. It is used for two things:
234 (1) To set the fallback host list in addresses, when delivering.
235 (2) To pass back the interface, port, protocol, and other options, for use
236 during callout verification.
239 tblock pointer to the transport instance block
240 addrlist list of addresses about to be transported
241 tf if not NULL, pointer to block in which to return options
242 uid the uid that will be set (not used)
243 gid the gid that will be set (not used)
244 errmsg place for error message (not used)
246 Returns: OK always (FAIL, DEFER not used)
250 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
251 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
253 smtp_transport_options_block *ob =
254 (smtp_transport_options_block *)(tblock->options_block);
256 errmsg = errmsg; /* Keep picky compilers happy */
260 /* Pass back options if required. This interface is getting very messy. */
264 tf->interface = ob->interface;
266 tf->protocol = ob->protocol;
267 tf->hosts = ob->hosts;
268 tf->hosts_override = ob->hosts_override;
269 tf->hosts_randomize = ob->hosts_randomize;
270 tf->gethostbyname = ob->gethostbyname;
271 tf->qualify_single = ob->dns_qualify_single;
272 tf->search_parents = ob->dns_search_parents;
273 tf->helo_data = ob->helo_data;
276 /* Set the fallback host list for all the addresses that don't have fallback
277 host lists, provided that the local host wasn't present in the original host
280 if (!testflag(addrlist, af_local_host_removed))
282 for (; addrlist != NULL; addrlist = addrlist->next)
283 if (addrlist->fallback_hosts == NULL)
284 addrlist->fallback_hosts = ob->fallback_hostlist;
292 /*************************************************
293 * Initialization entry point *
294 *************************************************/
296 /* Called for each instance, after its options have been read, to
297 enable consistency checks to be done, or anything else that needs
300 Argument: pointer to the transport instance block
305 smtp_transport_init(transport_instance *tblock)
307 smtp_transport_options_block *ob =
308 (smtp_transport_options_block *)(tblock->options_block);
310 /* Retry_use_local_part defaults FALSE if unset */
312 if (tblock->retry_use_local_part == TRUE_UNSET)
313 tblock->retry_use_local_part = FALSE;
315 /* Set the default port according to the protocol */
317 if (ob->port == NULL)
318 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
319 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
321 /* Set up the setup entry point, to be called before subprocesses for this
324 tblock->setup = smtp_transport_setup;
326 /* Complain if any of the timeouts are zero. */
328 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
329 ob->final_timeout <= 0)
330 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
331 "command, data, or final timeout value is zero for %s transport",
334 /* If hosts_override is set and there are local hosts, set the global
335 flag that stops verify from showing router hosts. */
337 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
339 /* If there are any fallback hosts listed, build a chain of host items
340 for them, but do not do any lookups at this time. */
342 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
349 /*************************************************
350 * Set delivery info into all active addresses *
351 *************************************************/
353 /* Only addresses whose status is >= PENDING are relevant. A lesser
354 status means that an address is not currently being processed.
357 addrlist points to a chain of addresses
358 errno_value to put in each address's errno field
359 msg to put in each address's message field
360 rc to put in each address's transport_return field
361 pass_message if TRUE, set the "pass message" flag in the address
363 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
364 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
365 this particular type of timeout.
371 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
376 if (errno_value == ERRNO_CONNECTTIMEOUT)
378 errno_value = ETIMEDOUT;
379 orvalue = RTEF_CTOUT;
381 for (addr = addrlist; addr != NULL; addr = addr->next)
383 if (addr->transport_return < PENDING) continue;
384 addr->basic_errno = errno_value;
385 addr->more_errno |= orvalue;
389 if (pass_message) setflag(addr, af_pass_message);
391 addr->transport_return = rc;
397 /*************************************************
398 * Check an SMTP response *
399 *************************************************/
401 /* This function is given an errno code and the SMTP response buffer
402 to analyse, together with the host identification for generating messages. It
403 sets an appropriate message and puts the first digit of the response code into
404 the yield variable. If no response was actually read, a suitable digit is
408 host the current host, to get its name for messages
409 errno_value pointer to the errno value
410 more_errno from the top address for use with ERRNO_FILTER_FAIL
411 buffer the SMTP response buffer
412 yield where to put a one-digit SMTP response code
413 message where to put an errror message
414 pass_message set TRUE if message is an SMTP response
416 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
419 static BOOL check_response(host_item *host, int *errno_value, int more_errno,
420 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
424 if (smtp_use_pipelining &&
425 (Ustrcmp(smtp_command, "MAIL") == 0 ||
426 Ustrcmp(smtp_command, "RCPT") == 0 ||
427 Ustrcmp(smtp_command, "DATA") == 0))
430 *yield = '4'; /* Default setting is to give a temporary error */
432 /* Handle response timeout */
434 if (*errno_value == ETIMEDOUT)
436 *message = US string_sprintf("SMTP timeout while connected to %s [%s] "
437 "after %s%s", host->name, host->address, pl, smtp_command);
438 if (transport_count > 0)
439 *message = US string_sprintf("%s (%d bytes written)", *message,
444 /* Handle malformed SMTP response */
446 if (*errno_value == ERRNO_SMTPFORMAT)
448 uschar *malfresp = string_printing(buffer);
449 while (isspace(*malfresp)) malfresp++;
451 *message = string_sprintf("Malformed SMTP reply (an empty line) from "
452 "%s [%s] in response to %s%s", host->name, host->address, pl,
455 *message = string_sprintf("Malformed SMTP reply from %s [%s] in response "
456 "to %s%s: %s", host->name, host->address, pl, smtp_command, malfresp);
460 /* Handle a failed filter process error; can't send QUIT as we mustn't
463 if (*errno_value == ERRNO_FILTER_FAIL)
465 *message = US string_sprintf("transport filter process failed (%d)%s",
467 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
471 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
474 if (*errno_value == ERRNO_CHHEADER_FAIL)
477 US string_sprintf("failed to expand headers_add or headers_remove: %s",
478 expand_string_message);
482 /* Handle failure to write a complete data block */
484 if (*errno_value == ERRNO_WRITEINCOMPLETE)
486 *message = US string_sprintf("failed to write a data block");
490 /* Handle error responses from the remote mailer. */
494 uschar *s = string_printing(buffer);
495 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
496 "host %s [%s]: %s", pl, smtp_command, host->name, host->address, s);
497 *pass_message = TRUE;
502 /* No data was read. If there is no errno, this must be the EOF (i.e.
503 connection closed) case, which causes deferral. An explicit connection reset
504 error has the same effect. Otherwise, put the host's identity in the message,
505 leaving the errno value to be interpreted as well. In all cases, we have to
506 assume the connection is now dead. */
508 if (*errno_value == 0 || *errno_value == ECONNRESET)
510 *errno_value = ERRNO_SMTPCLOSED;
511 *message = US string_sprintf("Remote host %s [%s] closed connection "
512 "in response to %s%s", host->name, host->address, pl, smtp_command);
514 else *message = US string_sprintf("%s [%s]", host->name, host->address);
521 /*************************************************
522 * Write error message to logs *
523 *************************************************/
525 /* This writes to the main log and to the message log.
528 addr the address item containing error information
529 host the current host
535 write_logs(address_item *addr, host_item *host)
537 if (addr->message != NULL)
539 uschar *message = addr->message;
540 if (addr->basic_errno > 0)
541 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
542 log_write(0, LOG_MAIN, "%s", message);
543 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
548 ((log_extra_selector & LX_outgoing_port) != 0)?
549 string_sprintf("%s [%s]:%d", host->name, host->address,
550 (host->port == PORT_NONE)? 25 : host->port)
552 string_sprintf("%s [%s]", host->name, host->address);
553 log_write(0, LOG_MAIN, "%s %s", msg, strerror(addr->basic_errno));
554 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), msg,
555 strerror(addr->basic_errno));
561 #ifdef EXPERIMENTAL_DBL
562 /*************************************************
563 * Write error message to database log *
564 *************************************************/
566 /* This writes to the database log
569 dbl_host_defer_query dbl_host_defer_query from the transport options block
570 addr the address item containing error information
571 host the current host
577 dbl_write_defer_log(uschar *dbl_host_defer_query, address_item *addr, host_item *host)
579 if (dbl_host_defer_query == NULL)
582 dbl_delivery_ip = string_copy(host->address);
583 dbl_delivery_port = (host->port == PORT_NONE)? 25 : host->port;
584 dbl_delivery_fqdn = string_copy(host->name);
585 dbl_delivery_local_part = string_copy(addr->local_part);
586 dbl_delivery_domain = string_copy(addr->domain);
587 dbl_defer_errno = addr->basic_errno;
589 dbl_defer_errstr = NULL;
590 if (addr->message != NULL)
591 if (addr->basic_errno > 0)
592 dbl_defer_errstr = string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno));
594 dbl_defer_errstr = string_copy(addr->message);
595 else if (addr->basic_errno > 0)
596 dbl_defer_errstr = string_copy(strerror(addr->basic_errno));
599 debug_printf(" DBL(host defer): dbl_host_defer_query=|%s| dbl_delivery_IP=%s\n", dbl_host_defer_query, dbl_delivery_ip);
601 expand_string(dbl_host_defer_query);
607 /*************************************************
608 * Synchronize SMTP responses *
609 *************************************************/
611 /* This function is called from smtp_deliver() to receive SMTP responses from
612 the server, and match them up with the commands to which they relate. When
613 PIPELINING is not in use, this function is called after every command, and is
614 therefore somewhat over-engineered, but it is simpler to use a single scheme
615 that works both with and without PIPELINING instead of having two separate sets
618 The set of commands that are buffered up with pipelining may start with MAIL
619 and may end with DATA; in between are RCPT commands that correspond to the
620 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
621 etc.) are never buffered.
623 Errors after MAIL or DATA abort the whole process leaving the response in the
624 buffer. After MAIL, pending responses are flushed, and the original command is
625 re-instated in big_buffer for error messages. For RCPT commands, the remote is
626 permitted to reject some recipient addresses while accepting others. However
627 certain errors clearly abort the whole process. Set the value in
628 transport_return to PENDING_OK if the address is accepted. If there is a
629 subsequent general error, it will get reset accordingly. If not, it will get
630 converted to OK at the end.
633 addrlist the complete address list
634 include_affixes TRUE if affixes include in RCPT
635 sync_addr ptr to the ptr of the one to start scanning at (updated)
636 host the host we are connected to
637 count the number of responses to read
639 include_sender true if 4xx retry is to include the sender it its key
640 pending_MAIL true if the first response is for MAIL
641 pending_DATA 0 if last command sent was not DATA
642 +1 if previously had a good recipient
643 -1 if not previously had a good recipient
644 inblock incoming SMTP block
645 timeout timeout value
646 buffer buffer for reading response
647 buffsize size of buffer
649 Returns: 3 if at least one address had 2xx and one had 5xx
650 2 if at least one address had 5xx but none had 2xx
651 1 if at least one host had a 2xx response, but none had 5xx
652 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
653 -1 timeout while reading RCPT response
654 -2 I/O or other non-response error for RCPT
655 -3 DATA or MAIL failed - errno and buffer set
659 sync_responses(address_item *addrlist, BOOL include_affixes,
660 address_item **sync_addr, host_item *host, int count,
661 BOOL address_retry_include_sender, BOOL pending_MAIL,
662 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
665 address_item *addr = *sync_addr;
668 /* Handle the response for a MAIL command. On error, reinstate the original
669 command in big_buffer for error message use, and flush any further pending
670 responses before returning, except after I/O errors and timeouts. */
675 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
677 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
678 if (errno == 0 && buffer[0] != 0)
680 uschar flushbuffer[4096];
682 if (buffer[0] == '4')
684 save_errno = ERRNO_MAIL4XX;
685 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
689 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
691 && (errno != 0 || flushbuffer[0] == 0))
700 if (pending_DATA) count--; /* Number of RCPT responses to come */
702 /* Read and handle the required number of RCPT responses, matching each one up
703 with an address by scanning for the next address whose status is PENDING_DEFER.
708 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
710 /* The address was accepted */
712 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
715 addr->transport_return = PENDING_OK;
717 /* If af_dr_retry_exists is set, there was a routing delay on this address;
718 ensure that any address-specific retry record is expunged. We do this both
719 for the basic key and for the version that also includes the sender. */
721 if (testflag(addr, af_dr_retry_exists))
723 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
725 retry_add_item(addr, altkey, rf_delete);
726 retry_add_item(addr, addr->address_retry_key, rf_delete);
730 /* Timeout while reading the response */
732 else if (errno == ETIMEDOUT)
734 int save_errno = errno;
735 uschar *message = string_sprintf("SMTP timeout while connected to %s [%s] "
736 "after RCPT TO:<%s>", host->name, host->address,
737 transport_rcpt_address(addr, include_affixes));
738 set_errno(addrlist, save_errno, message, DEFER, FALSE);
739 retry_add_item(addr, addr->address_retry_key, 0);
740 update_waiting = FALSE;
744 /* Handle other errors in obtaining an SMTP response by returning -1. This
745 will cause all the addresses to be deferred. Restore the SMTP command in
746 big_buffer for which we are checking the response, so the error message
749 else if (errno != 0 || buffer[0] == 0)
751 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
752 transport_rcpt_address(addr, include_affixes));
756 /* Handle SMTP permanent and temporary response codes. */
761 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
762 "host %s [%s]: %s", transport_rcpt_address(addr, include_affixes),
763 host->name, host->address, string_printing(buffer));
764 setflag(addr, af_pass_message);
765 deliver_msglog("%s %s\n", tod_stamp(tod_log), addr->message);
767 /* The response was 5xx */
769 if (buffer[0] == '5')
771 addr->transport_return = FAIL;
775 /* The response was 4xx */
779 addr->transport_return = DEFER;
780 addr->basic_errno = ERRNO_RCPT4XX;
781 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
783 /* Log temporary errors if there are more hosts to be tried. */
785 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", addr->message);
787 /* Do not put this message on the list of those waiting for specific
788 hosts, as otherwise it is likely to be tried too often. */
790 update_waiting = FALSE;
792 /* Add a retry item for the address so that it doesn't get tried again
793 too soon. If address_retry_include_sender is true, add the sender address
796 if (address_retry_include_sender)
798 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
800 retry_add_item(addr, altkey, 0);
802 else retry_add_item(addr, addr->address_retry_key, 0);
805 } /* Loop for next RCPT response */
807 /* Update where to start at for the next block of responses, unless we
808 have already handled all the addresses. */
810 if (addr != NULL) *sync_addr = addr->next;
812 /* Handle a response to DATA. If we have not had any good recipients, either
813 previously or in this block, the response is ignored. */
815 if (pending_DATA != 0 &&
816 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
821 if (pending_DATA > 0 || (yield & 1) != 0)
823 if (errno == 0 && buffer[0] == '4')
825 errno = ERRNO_DATA4XX;
826 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
830 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
831 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
832 "is in use and there were no good recipients\n", msg);
835 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
836 present) received 3xx. If any RCPTs were handled and yielded anything other
837 than 4xx, yield will be set non-zero. */
844 /*************************************************
845 * Deliver address list to given host *
846 *************************************************/
848 /* If continue_hostname is not null, we get here only when continuing to
849 deliver down an existing channel. The channel was passed as the standard
850 input. TLS is never active on a passed channel; the previous process always
851 closes it down before passing the connection on.
853 Otherwise, we have to make a connection to the remote host, and do the
854 initial protocol exchange.
856 When running as an MUA wrapper, if the sender or any recipient is rejected,
857 temporarily or permanently, we force failure for all recipients.
860 addrlist chain of potential addresses to deliver; only those whose
861 transport_return field is set to PENDING_DEFER are currently
862 being processed; others should be skipped - they have either
863 been delivered to an earlier host or IP address, or been
864 failed by one of them.
865 host host to deliver to
866 host_af AF_INET or AF_INET6
867 port default TCP/IP port to use, in host byte order
868 interface interface to bind to, or NULL
869 tblock transport instance block
870 copy_host TRUE if host set in addr->host_used must be copied, because
871 it is specific to this call of the transport
872 message_defer set TRUE if yield is OK, but all addresses were deferred
873 because of a non-recipient, non-host failure, that is, a
874 4xx response to MAIL FROM, DATA, or ".". This is a defer
875 that is specific to the message.
876 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
877 a second attempt after TLS initialization fails
879 Returns: OK - the connection was made and the delivery attempted;
880 the result for each address is in its data block.
881 DEFER - the connection could not be made, or something failed
882 while setting up the SMTP session, or there was a
883 non-message-specific error, such as a timeout.
884 ERROR - a filter command is specified for this transport,
885 and there was a problem setting it up; OR helo_data
886 or add_headers or authenticated_sender is specified
887 for this transport, and the string failed to expand
891 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
892 uschar *interface, transport_instance *tblock, BOOL copy_host,
893 BOOL *message_defer, BOOL suppress_tls)
896 address_item *sync_addr;
897 address_item *first_addr = addrlist;
902 time_t start_delivery_time = time(NULL);
903 smtp_transport_options_block *ob =
904 (smtp_transport_options_block *)(tblock->options_block);
905 BOOL lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
906 BOOL smtps = strcmpic(ob->protocol, US"smtps") == 0;
908 BOOL send_rset = TRUE;
909 BOOL send_quit = TRUE;
910 BOOL setting_up = TRUE;
911 BOOL completed_address = FALSE;
914 BOOL pass_message = FALSE;
915 smtp_inblock inblock;
916 smtp_outblock outblock;
917 int max_rcpt = tblock->max_addresses;
918 uschar *igquotstr = US"";
919 uschar *local_authenticated_sender = authenticated_sender;
920 uschar *helo_data = NULL;
921 uschar *message = NULL;
922 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
925 uschar inbuffer[4096];
926 uschar outbuffer[1024];
928 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
930 *message_defer = FALSE;
931 smtp_command = US"initial connection";
932 if (max_rcpt == 0) max_rcpt = 999999;
934 /* Set up the buffer for reading SMTP response packets. */
936 inblock.buffer = inbuffer;
937 inblock.buffersize = sizeof(inbuffer);
938 inblock.ptr = inbuffer;
939 inblock.ptrend = inbuffer;
941 /* Set up the buffer for holding SMTP commands while pipelining */
943 outblock.buffer = outbuffer;
944 outblock.buffersize = sizeof(outbuffer);
945 outblock.ptr = outbuffer;
946 outblock.cmd_count = 0;
947 outblock.authenticating = FALSE;
949 /* Reset the parameters of a TLS session. */
954 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
958 /* If an authenticated_sender override has been specified for this transport
959 instance, expand it. If the expansion is forced to fail, and there was already
960 an authenticated_sender for this message, the original value will be used.
961 Other expansion failures are serious. An empty result is ignored, but there is
962 otherwise no check - this feature is expected to be used with LMTP and other
963 cases where non-standard addresses (e.g. without domains) might be required. */
965 if (ob->authenticated_sender != NULL)
967 uschar *new = expand_string(ob->authenticated_sender);
970 if (!expand_string_forcedfail)
972 uschar *message = string_sprintf("failed to expand "
973 "authenticated_sender: %s", expand_string_message);
974 set_errno(addrlist, 0, message, DEFER, FALSE);
978 else if (new[0] != 0) local_authenticated_sender = new;
984 set_errno(addrlist, 0, US"TLS support not available", DEFER, FALSE);
989 /* Make a connection to the host if this isn't a continued delivery, and handle
990 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
991 specially so they can be identified for retries. */
993 if (continue_hostname == NULL)
995 inblock.sock = outblock.sock =
996 smtp_connect(host, host_af, port, interface, ob->connect_timeout,
997 ob->keepalive); /* This puts port into host->port */
999 if (inblock.sock < 0)
1001 set_errno(addrlist, (errno == ETIMEDOUT)? ERRNO_CONNECTTIMEOUT : errno,
1002 NULL, DEFER, FALSE);
1006 /* Expand the greeting message while waiting for the initial response. (Makes
1007 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1008 delayed till here so that $sending_interface and $sending_port are set. */
1010 helo_data = expand_string(ob->helo_data);
1012 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1013 is nevertheless a reasonably clean way of programming this kind of logic,
1014 where you want to escape on any error. */
1018 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1019 ob->command_timeout)) goto RESPONSE_FAILED;
1021 /* Now check if the helo_data expansion went well, and sign off cleanly if
1024 if (helo_data == NULL)
1026 uschar *message = string_sprintf("failed to expand helo_data: %s",
1027 expand_string_message);
1028 set_errno(addrlist, 0, message, DEFER, FALSE);
1034 /** Debugging without sending a message
1035 addrlist->transport_return = DEFER;
1039 /* Errors that occur after this point follow an SMTP command, which is
1040 left in big_buffer by smtp_write_command() for use in error messages. */
1042 smtp_command = big_buffer;
1044 /* Tell the remote who we are...
1046 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1047 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1048 greeting is of this form. The assumption was that the far end supports it
1049 properly... but experience shows that there are some that give 5xx responses,
1050 even though the banner includes "ESMTP" (there's a bloody-minded one that
1051 says "ESMTP not spoken here"). Cope with that case.
1053 September 2000: Time has passed, and it seems reasonable now to always send
1054 EHLO at the start. It is also convenient to make the change while installing
1057 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1058 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1059 would be no way to send out the mails, so there is now a host list
1060 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1061 PIPELINING problem as well. Maybe it can also be useful to cure other
1062 problems with broken servers.
1064 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1065 Then somebody tried it with a Microsoft mailer... It seems that all other
1066 mailers use upper case for some reason (the RFC is quite clear about case
1067 independence) so, for peace of mind, I gave in. */
1069 esmtp = verify_check_this_host(&(ob->hosts_avoid_esmtp), NULL,
1070 host->name, host->address, NULL) != OK;
1072 /* Alas; be careful, since this goto is not an error-out, so conceivably
1073 we might set data between here and the target which we assume to exist
1074 and be usable. I can see this coming back to bite us. */
1079 suppress_tls = FALSE;
1080 ob->tls_tempfail_tryclear = FALSE;
1081 smtp_command = US"SSL-on-connect";
1088 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1089 lmtp? "LHLO" : "EHLO", helo_data) < 0)
1091 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1092 ob->command_timeout))
1094 if (errno != 0 || buffer[0] == 0 || lmtp) goto RESPONSE_FAILED;
1101 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1106 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1108 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1109 ob->command_timeout)) goto RESPONSE_FAILED;
1112 /* Set IGNOREQUOTA if the response to LHLO specifies support and the
1113 lmtp_ignore_quota option was set. */
1115 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1116 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1117 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1119 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1122 tls_offered = esmtp &&
1123 pcre_exec(regex_STARTTLS, NULL, CS buffer, Ustrlen(buffer), 0,
1124 PCRE_EOPT, NULL, 0) >= 0;
1128 /* For continuing deliveries down the same channel, the socket is the standard
1129 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1130 below). Set up the pointer to where subsequent commands will be left, for
1131 error messages. Note that smtp_use_size and smtp_use_pipelining will have been
1132 set from the command line if they were set in the process that passed the
1137 inblock.sock = outblock.sock = fileno(stdin);
1138 smtp_command = big_buffer;
1139 host->port = port; /* Record the port that was used */
1142 /* If TLS is available on this connection, whether continued or not, attempt to
1143 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1144 send another EHLO - the server may give a different answer in secure mode. We
1145 use a separate buffer for reading the response to STARTTLS so that if it is
1146 negative, the original EHLO data is available for subsequent analysis, should
1147 the client not be required to use TLS. If the response is bad, copy the buffer
1148 for error analysis. */
1151 if (tls_offered && !suppress_tls &&
1152 verify_check_this_host(&(ob->hosts_avoid_tls), NULL, host->name,
1153 host->address, NULL) != OK)
1155 uschar buffer2[4096];
1156 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1159 /* If there is an I/O error, transmission of this message is deferred. If
1160 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1161 false, we also defer. However, if there is a temporary rejection of STARTTLS
1162 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1163 STARTTLS, we carry on. This means we will try to send the message in clear,
1164 unless the host is in hosts_require_tls (tested below). */
1166 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1167 ob->command_timeout))
1169 if (errno != 0 || buffer2[0] == 0 ||
1170 (buffer2[0] == '4' && !ob->tls_tempfail_tryclear))
1172 Ustrncpy(buffer, buffer2, sizeof(buffer));
1173 goto RESPONSE_FAILED;
1177 /* STARTTLS accepted: try to negotiate a TLS session. */
1182 int rc = tls_client_start(inblock.sock,
1185 NULL, /* No DH param */
1186 ob->tls_certificate,
1189 ob->tls_verify_certificates,
1191 ob->tls_require_ciphers,
1192 ob->command_timeout);
1194 /* TLS negotiation failed; give an error. From outside, this function may
1195 be called again to try in clear on a new connection, if the options permit
1196 it for this host. */
1200 save_errno = ERRNO_TLSFAILURE;
1201 message = US"failure while setting up TLS session";
1206 /* TLS session is set up */
1208 for (addr = addrlist; addr != NULL; addr = addr->next)
1210 if (addr->transport_return == PENDING_DEFER)
1212 addr->cipher = tls_cipher;
1213 addr->peerdn = tls_peerdn;
1219 /* if smtps, we'll have smtp_command set to something else; always safe to
1221 smtp_command = big_buffer;
1223 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1224 helo_data is null, we are dealing with a connection that was passed from
1225 another process, and so we won't have expanded helo_data above. We have to
1226 expand it here. $sending_ip_address and $sending_port are set up right at the
1227 start of the Exim process (in exim.c). */
1229 if (tls_active >= 0)
1232 if (helo_data == NULL)
1234 helo_data = expand_string(ob->helo_data);
1235 if (helo_data == NULL)
1237 uschar *message = string_sprintf("failed to expand helo_data: %s",
1238 expand_string_message);
1239 set_errno(addrlist, 0, message, DEFER, FALSE);
1245 /* For SMTPS we need to wait for the initial OK response. */
1248 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1249 ob->command_timeout)) goto RESPONSE_FAILED;
1253 greeting_cmd = "EHLO";
1256 greeting_cmd = "HELO";
1258 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1261 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1262 lmtp? "LHLO" : greeting_cmd, helo_data) < 0)
1264 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1265 ob->command_timeout))
1266 goto RESPONSE_FAILED;
1269 /* If the host is required to use a secure channel, ensure that we
1272 else if (verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
1273 host->address, NULL) == OK)
1275 save_errno = ERRNO_TLSREQUIRED;
1276 message = string_sprintf("a TLS session is required for %s [%s], but %s",
1277 host->name, host->address,
1278 tls_offered? "an attempt to start TLS failed" :
1279 "the server did not offer TLS support");
1284 /* If TLS is active, we have just started it up and re-done the EHLO command,
1285 so its response needs to be analyzed. If TLS is not active and this is a
1286 continued session down a previously-used socket, we haven't just done EHLO, so
1289 if (continue_hostname == NULL
1296 uschar *fail_reason = US"server did not advertise AUTH support";
1298 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
1299 lmtp_ignore_quota option was set. */
1301 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1302 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1303 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1305 /* If the response to EHLO specified support for the SIZE parameter, note
1306 this, provided size_addition is non-negative. */
1308 smtp_use_size = esmtp && ob->size_addition >= 0 &&
1309 pcre_exec(regex_SIZE, NULL, CS buffer, Ustrlen(CS buffer), 0,
1310 PCRE_EOPT, NULL, 0) >= 0;
1312 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
1313 the current host, esmtp will be false, so PIPELINING can never be used. If
1314 the current host matches hosts_avoid_pipelining, don't do it. */
1316 smtp_use_pipelining = esmtp &&
1317 verify_check_this_host(&(ob->hosts_avoid_pipelining), NULL, host->name,
1318 host->address, NULL) != OK &&
1319 pcre_exec(regex_PIPELINING, NULL, CS buffer, Ustrlen(CS buffer), 0,
1320 PCRE_EOPT, NULL, 0) >= 0;
1322 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
1323 smtp_use_pipelining? "" : "not ");
1325 /* Note if the response to EHLO specifies support for the AUTH extension.
1326 If it has, check that this host is one we want to authenticate to, and do
1327 the business. The host name and address must be available when the
1328 authenticator's client driver is running. */
1330 smtp_authenticated = FALSE;
1331 require_auth = verify_check_this_host(&(ob->hosts_require_auth), NULL,
1332 host->name, host->address, NULL);
1334 if (esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
1336 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
1337 expand_nmax = -1; /* reset */
1339 /* Must not do this check until after we have saved the result of the
1340 regex match above. */
1342 if (require_auth == OK ||
1343 verify_check_this_host(&(ob->hosts_try_auth), NULL, host->name,
1344 host->address, NULL) == OK)
1347 fail_reason = US"no common mechanisms were found";
1349 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1351 /* Scan the configured authenticators looking for one which is configured
1352 for use as a client, which is not suppressed by client_condition, and
1353 whose name matches an authentication mechanism supported by the server.
1354 If one is found, attempt to authenticate by calling its client function.
1357 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1361 (au->client_condition != NULL &&
1362 !expand_check_condition(au->client_condition, au->name,
1363 US"client authenticator")))
1365 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1367 (au->client)? "client_condition is false" :
1368 "not configured as a client");
1372 /* Loop to scan supported server mechanisms */
1377 int len = Ustrlen(au->public_name);
1378 while (isspace(*p)) p++;
1380 if (strncmpic(au->public_name, p, len) != 0 ||
1381 (p[len] != 0 && !isspace(p[len])))
1383 while (*p != 0 && !isspace(*p)) p++;
1387 /* Found data for a listed mechanism. Call its client entry. Set
1388 a flag in the outblock so that data is overwritten after sending so
1389 that reflections don't show it. */
1391 fail_reason = US"authentication attempt(s) failed";
1392 outblock.authenticating = TRUE;
1393 rc = (au->info->clientcode)(au, &inblock, &outblock,
1394 ob->command_timeout, buffer, sizeof(buffer));
1395 outblock.authenticating = FALSE;
1396 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1399 /* A temporary authentication failure must hold up delivery to
1400 this host. After a permanent authentication failure, we carry on
1401 to try other authentication methods. If all fail hard, try to
1402 deliver the message unauthenticated unless require_auth was set. */
1407 smtp_authenticated = TRUE; /* stops the outer loop */
1410 /* Failure after writing a command */
1415 /* Failure after reading a response */
1418 if (errno != 0 || buffer[0] != '5') goto RESPONSE_FAILED;
1419 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1420 au->name, host->name, host->address, buffer);
1423 /* Failure by some other means. In effect, the authenticator
1424 decided it wasn't prepared to handle this case. Typically this
1425 is the result of "fail" in an expansion string. Do we need to
1426 log anything here? Feb 2006: a message is now put in the buffer
1427 if logging is required. */
1431 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1432 "authentication H=%s [%s] %s", au->name, host->name,
1433 host->address, buffer);
1436 /* Internal problem, message in buffer. */
1440 set_errno(addrlist, 0, string_copy(buffer), DEFER, FALSE);
1444 break; /* If not authenticated, try next authenticator */
1445 } /* Loop for scanning supported server mechanisms */
1446 } /* Loop for further authenticators */
1450 /* If we haven't authenticated, but are required to, give up. */
1452 if (require_auth == OK && !smtp_authenticated)
1455 set_errno(addrlist, ERRNO_AUTHFAIL,
1456 string_sprintf("authentication required but %s", fail_reason), DEFER,
1462 /* The setting up of the SMTP call is now complete. Any subsequent errors are
1463 message-specific. */
1467 /* If there is a filter command specified for this transport, we can now
1468 set it up. This cannot be done until the identify of the host is known. */
1470 if (tblock->filter_command != NULL)
1474 sprintf(CS buffer, "%.50s transport", tblock->name);
1475 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
1476 TRUE, DEFER, addrlist, buffer, NULL);
1477 transport_filter_timeout = tblock->filter_timeout;
1479 /* On failure, copy the error to all addresses, abandon the SMTP call, and
1484 set_errno(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
1492 /* For messages that have more than the maximum number of envelope recipients,
1493 we want to send several transactions down the same SMTP connection. (See
1494 comments in deliver.c as to how this reconciles, heuristically, with
1495 remote_max_parallel.) This optimization was added to Exim after the following
1496 code was already working. The simplest way to put it in without disturbing the
1497 code was to use a goto to jump back to this point when there is another
1498 transaction to handle. */
1501 sync_addr = first_addr;
1505 completed_address = FALSE;
1508 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
1509 qualification, send it, adding something to the message size to allow for
1510 imprecision and things that get added en route. Exim keeps the number of lines
1511 in a message, so we can give an accurate value for the original message, but we
1512 need some additional to handle added headers. (Double "." characters don't get
1513 included in the count.) */
1520 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
1524 /* Add the authenticated sender address if present */
1526 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1527 local_authenticated_sender != NULL)
1529 string_format(p, sizeof(buffer) - (p-buffer), " AUTH=%s",
1530 auth_xtextencode(local_authenticated_sender,
1531 Ustrlen(local_authenticated_sender)));
1534 /* From here until we send the DATA command, we can make use of PIPELINING
1535 if the server host supports it. The code has to be able to check the responses
1536 at any point, for when the buffer fills up, so we write it totally generally.
1537 When PIPELINING is off, each command written reports that it has flushed the
1540 pending_MAIL = TRUE; /* The block starts with MAIL */
1542 rc = smtp_write_command(&outblock, smtp_use_pipelining,
1543 "MAIL FROM:<%s>%s\r\n", return_path, buffer);
1544 mail_command = string_copy(big_buffer); /* Save for later error message */
1548 case -1: /* Transmission error */
1551 case +1: /* Block was sent */
1552 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1553 ob->command_timeout))
1555 if (errno == 0 && buffer[0] == '4')
1557 errno = ERRNO_MAIL4XX;
1558 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1560 goto RESPONSE_FAILED;
1562 pending_MAIL = FALSE;
1566 /* Pass over all the relevant recipient addresses for this host, which are the
1567 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
1568 several before we have to read the responses for those seen so far. This
1569 checking is done by a subroutine because it also needs to be done at the end.
1570 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
1571 the next one if not all are sent.
1573 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
1574 last address because we want to abort if any recipients have any kind of
1575 problem, temporary or permanent. We know that all recipient addresses will have
1576 the PENDING_DEFER status, because only one attempt is ever made, and we know
1577 that max_rcpt will be large, so all addresses will be done at once. */
1579 for (addr = first_addr;
1580 address_count < max_rcpt && addr != NULL;
1586 if (addr->transport_return != PENDING_DEFER) continue;
1589 no_flush = smtp_use_pipelining && (!mua_wrapper || addr->next != NULL);
1591 /* Now send the RCPT command, and process outstanding responses when
1592 necessary. After a timeout on RCPT, we just end the function, leaving the
1593 yield as OK, because this error can often mean that there is a problem with
1594 just one address, so we don't want to delay the host. */
1596 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s\r\n",
1597 transport_rcpt_address(addr, tblock->rcpt_include_affixes), igquotstr);
1598 if (count < 0) goto SEND_FAILED;
1601 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
1602 &sync_addr, host, count, ob->address_retry_include_sender,
1603 pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
1606 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1607 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1610 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1611 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1612 case 0: /* No 2xx or 5xx, but no probs */
1615 case -1: goto END_OFF; /* Timeout on RCPT */
1616 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
1618 pending_MAIL = FALSE; /* Dealt with MAIL */
1620 } /* Loop for next address */
1622 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
1623 permanently or temporarily. We should have flushed and synced after the last
1628 address_item *badaddr;
1629 for (badaddr = first_addr; badaddr != NULL; badaddr = badaddr->next)
1631 if (badaddr->transport_return != PENDING_OK) break;
1633 if (badaddr != NULL)
1635 set_errno(addrlist, 0, badaddr->message, FAIL,
1636 testflag(badaddr, af_pass_message));
1641 /* If ok is TRUE, we know we have got at least one good recipient, and must now
1642 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
1643 have a good recipient buffered up if we are pipelining. We don't want to waste
1644 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
1645 are pipelining. The responses are all handled by sync_responses(). */
1647 if (ok || (smtp_use_pipelining && !mua_wrapper))
1649 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
1650 if (count < 0) goto SEND_FAILED;
1651 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
1652 host, count, ob->address_retry_include_sender, pending_MAIL,
1653 ok? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
1655 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1656 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1659 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1660 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1661 case 0: break; /* No 2xx or 5xx, but no probs */
1663 case -1: goto END_OFF; /* Timeout on RCPT */
1664 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
1668 /* Save the first address of the next batch. */
1672 /* If there were no good recipients (but otherwise there have been no
1673 problems), just set ok TRUE, since we have handled address-specific errors
1674 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
1675 for handling the SMTP dot-handling protocol, flagging to apply to headers as
1676 well as body. Set the appropriate timeout value to be used for each chunk.
1677 (Haven't been able to make it work using select() for writing yet.) */
1679 if (!ok) ok = TRUE; else
1681 sigalrm_seen = FALSE;
1682 transport_write_timeout = ob->data_timeout;
1683 smtp_command = US"sending data block"; /* For error messages */
1684 DEBUG(D_transport|D_v)
1685 debug_printf(" SMTP>> writing message and terminating \".\"\n");
1686 transport_count = 0;
1687 #ifndef DISABLE_DKIM
1688 ok = dkim_transport_write_message(addrlist, inblock.sock,
1689 topt_use_crlf | topt_end_dot | topt_escape_headers |
1690 (tblock->body_only? topt_no_headers : 0) |
1691 (tblock->headers_only? topt_no_body : 0) |
1692 (tblock->return_path_add? topt_add_return_path : 0) |
1693 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1694 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1695 0, /* No size limit */
1696 tblock->add_headers, tblock->remove_headers,
1697 US".", US"..", /* Escaping strings */
1698 tblock->rewrite_rules, tblock->rewrite_existflags,
1699 ob->dkim_private_key, ob->dkim_domain, ob->dkim_selector,
1700 ob->dkim_canon, ob->dkim_strict, ob->dkim_sign_headers
1703 ok = transport_write_message(addrlist, inblock.sock,
1704 topt_use_crlf | topt_end_dot | topt_escape_headers |
1705 (tblock->body_only? topt_no_headers : 0) |
1706 (tblock->headers_only? topt_no_body : 0) |
1707 (tblock->return_path_add? topt_add_return_path : 0) |
1708 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1709 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1710 0, /* No size limit */
1711 tblock->add_headers, tblock->remove_headers,
1712 US".", US"..", /* Escaping strings */
1713 tblock->rewrite_rules, tblock->rewrite_existflags);
1716 /* transport_write_message() uses write() because it is called from other
1717 places to write to non-sockets. This means that under some OS (e.g. Solaris)
1718 it can exit with "Broken pipe" as its error. This really means that the
1719 socket got closed at the far end. */
1721 transport_write_timeout = 0; /* for subsequent transports */
1723 /* Failure can either be some kind of I/O disaster (including timeout),
1724 or the failure of a transport filter or the expansion of added headers. */
1728 buffer[0] = 0; /* There hasn't been a response */
1729 goto RESPONSE_FAILED;
1732 /* We used to send the terminating "." explicitly here, but because of
1733 buffering effects at both ends of TCP/IP connections, you don't gain
1734 anything by keeping it separate, so it might as well go in the final
1735 data buffer for efficiency. This is now done by setting the topt_end_dot
1738 smtp_command = US"end of data";
1740 /* For SMTP, we now read a single response that applies to the whole message.
1741 If it is OK, then all the addresses have been delivered. */
1745 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1747 if (!ok && errno == 0 && buffer[0] == '4')
1749 errno = ERRNO_DATA4XX;
1750 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1754 /* For LMTP, we get back a response for every RCPT command that we sent;
1755 some may be accepted and some rejected. For those that get a response, their
1756 status is fixed; any that are accepted have been handed over, even if later
1757 responses crash - at least, that's how I read RFC 2033.
1759 If all went well, mark the recipient addresses as completed, record which
1760 host/IPaddress they were delivered to, and cut out RSET when sending another
1761 message down the same channel. Write the completed addresses to the journal
1762 now so that they are recorded in case there is a crash of hardware or
1763 software before the spool gets updated. Also record the final SMTP
1764 confirmation if needed (for SMTP only). */
1769 int delivery_time = (int)(time(NULL) - start_delivery_time);
1772 uschar *conf = NULL;
1775 /* Make a copy of the host if it is local to this invocation
1776 of the transport. */
1780 thost = store_get(sizeof(host_item));
1782 thost->name = string_copy(host->name);
1783 thost->address = string_copy(host->address);
1787 /* Set up confirmation if needed - applies only to SMTP */
1790 #ifndef EXPERIMENTAL_DBL
1791 (log_extra_selector & LX_smtp_confirmation) != 0 &&
1796 uschar *s = string_printing(buffer);
1797 conf = (s == buffer)? (uschar *)string_copy(s) : s;
1800 /* Process all transported addresses - for LMTP, read a status for
1803 for (addr = addrlist; addr != first_addr; addr = addr->next)
1805 if (addr->transport_return != PENDING_OK) continue;
1807 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
1808 remaining addresses. Otherwise, it's a return code for just the one
1809 address. For temporary errors, add a retry item for the address so that
1810 it doesn't get tried again too soon. */
1814 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1817 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
1818 addr->message = string_sprintf("LMTP error after %s: %s",
1819 big_buffer, string_printing(buffer));
1820 setflag(addr, af_pass_message); /* Allow message to go to user */
1821 if (buffer[0] == '5')
1822 addr->transport_return = FAIL;
1825 errno = ERRNO_DATA4XX;
1826 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1827 addr->transport_return = DEFER;
1828 retry_add_item(addr, addr->address_retry_key, 0);
1832 completed_address = TRUE; /* NOW we can set this flag */
1833 if ((log_extra_selector & LX_smtp_confirmation) != 0)
1835 uschar *s = string_printing(buffer);
1836 conf = (s == buffer)? (uschar *)string_copy(s) : s;
1840 /* SMTP, or success return from LMTP for this address. Pass back the
1841 actual host that was used. */
1843 addr->transport_return = OK;
1844 addr->more_errno = delivery_time;
1845 addr->host_used = thost;
1846 addr->special_action = flag;
1847 addr->message = conf;
1850 /* Update the journal. For homonymic addresses, use the base address plus
1851 the transport name. See lots of comments in deliver.c about the reasons
1852 for the complications when homonyms are involved. Just carry on after
1853 write error, as it may prove possible to update the spool file later. */
1855 if (testflag(addr, af_homonym))
1856 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
1858 sprintf(CS buffer, "%.500s\n", addr->unique);
1860 DEBUG(D_deliver) debug_printf("journalling %s", buffer);
1861 len = Ustrlen(CS buffer);
1862 if (write(journal_fd, buffer, len) != len)
1863 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
1864 "%s: %s", buffer, strerror(errno));
1867 /* Ensure the journal file is pushed out to disk. */
1869 if (EXIMfsync(journal_fd) < 0)
1870 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
1876 /* Handle general (not specific to one address) failures here. The value of ok
1877 is used to skip over this code on the falling through case. A timeout causes a
1878 deferral. Other errors may defer or fail according to the response code, and
1879 may set up a special errno value, e.g. after connection chopped, which is
1880 assumed if errno == 0 and there is no text in the buffer. If control reaches
1881 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
1882 the problem is not related to this specific message. */
1891 send_quit = check_response(host, &save_errno, addrlist->more_errno,
1892 buffer, &code, &message, &pass_message);
1898 message = US string_sprintf("send() to %s [%s] failed: %s",
1899 host->name, host->address, strerror(save_errno));
1903 /* This label is jumped to directly when a TLS negotiation has failed,
1904 or was not done for a host for which it is required. Values will be set
1905 in message and save_errno, and setting_up will always be true. Treat as
1906 a temporary error. */
1913 /* If the failure happened while setting up the call, see if the failure was
1914 a 5xx response (this will either be on connection, or following HELO - a 5xx
1915 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
1916 never going to accept them. For other errors during setting up (timeouts or
1917 whatever), defer all addresses, and yield DEFER, so that the host is not
1918 tried again for a while. */
1921 ok = FALSE; /* For when reached by GOTO */
1927 set_errno(addrlist, save_errno, message, FAIL, pass_message);
1931 set_errno(addrlist, save_errno, message, DEFER, pass_message);
1936 /* We want to handle timeouts after MAIL or "." and loss of connection after
1937 "." specially. They can indicate a problem with the sender address or with
1938 the contents of the message rather than a real error on the connection. These
1939 cases are treated in the same way as a 4xx response. This next bit of code
1940 does the classification. */
1951 message_error = TRUE;
1955 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
1956 Ustrncmp(smtp_command,"end ",4) == 0;
1959 case ERRNO_SMTPCLOSED:
1960 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
1964 message_error = FALSE;
1968 /* Handle the cases that are treated as message errors. These are:
1970 (a) negative response or timeout after MAIL
1971 (b) negative response after DATA
1972 (c) negative response or timeout or dropped connection after "."
1974 It won't be a negative response or timeout after RCPT, as that is dealt
1975 with separately above. The action in all cases is to set an appropriate
1976 error code for all the addresses, but to leave yield set to OK because the
1977 host itself has not failed. Of course, it might in practice have failed
1978 when we've had a timeout, but if so, we'll discover that at the next
1979 delivery attempt. For a temporary error, set the message_defer flag, and
1980 write to the logs for information if this is not the last host. The error
1981 for the last host will be logged as part of the address's log line. */
1985 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
1986 set_errno(addrlist, save_errno, message, (code == '5')? FAIL : DEFER,
1989 /* If there's an errno, the message contains just the identity of
1992 if (code != '5') /* Anything other than 5 is treated as temporary */
1995 message = US string_sprintf("%s: %s", message, strerror(save_errno));
1996 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
1997 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
1998 *message_defer = TRUE;
2002 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
2003 ".", or some other transportation error. We defer all addresses and yield
2004 DEFER, except for the case of failed add_headers expansion, or a transport
2005 filter failure, when the yield should be ERROR, to stop it trying other
2010 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
2011 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
2012 set_errno(addrlist, save_errno, message, DEFER, pass_message);
2018 /* If all has gone well, send_quit will be set TRUE, implying we can end the
2019 SMTP session tidily. However, if there were too many addresses to send in one
2020 message (indicated by first_addr being non-NULL) we want to carry on with the
2021 rest of them. Also, it is desirable to send more than one message down the SMTP
2022 connection if there are several waiting, provided we haven't already sent so
2023 many as to hit the configured limit. The function transport_check_waiting looks
2024 for a waiting message and returns its id. Then transport_pass_socket tries to
2025 set up a continued delivery by passing the socket on to another process. The
2026 variable send_rset is FALSE if a message has just been successfully transfered.
2028 If we are already sending down a continued channel, there may be further
2029 addresses not yet delivered that are aimed at the same host, but which have not
2030 been passed in this run of the transport. In this case, continue_more will be
2031 true, and all we should do is send RSET if necessary, and return, leaving the
2034 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
2035 do not want to continue with other messages down the same channel, because that
2036 can lead to looping between two or more messages, all with the same,
2037 temporarily failing address(es). [The retry information isn't updated yet, so
2038 new processes keep on trying.] We probably also don't want to try more of this
2039 message's addresses either.
2041 If we have started a TLS session, we have to end it before passing the
2042 connection to a new process. However, not all servers can handle this (Exim
2043 can), so we do not pass such a connection on if the host matches
2044 hosts_nopass_tls. */
2047 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
2048 "yield=%d first_address is %sNULL\n", ok, send_quit, send_rset,
2049 continue_more, yield, (first_addr == NULL)? "":"not ");
2051 if (completed_address && ok && send_quit)
2054 if (first_addr != NULL || continue_more ||
2057 verify_check_this_host(&(ob->hosts_nopass_tls), NULL, host->name,
2058 host->address, NULL) != OK)
2060 transport_check_waiting(tblock->name, host->name,
2061 tblock->connection_max_messages, new_message_id, &more)
2069 if (! (ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
2071 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
2072 host->address, strerror(save_errno));
2075 else if (! (ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2076 ob->command_timeout)))
2079 send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
2083 DEBUG(D_transport) debug_printf("%s\n", msg);
2088 /* Either RSET was not needed, or it succeeded */
2092 if (first_addr != NULL) /* More addresses still to be sent */
2093 { /* in this run of the transport */
2094 continue_sequence++; /* Causes * in logging */
2097 if (continue_more) return yield; /* More addresses for another run */
2099 /* Pass the socket to a new Exim process. Before doing so, we must shut
2100 down TLS. Not all MTAs allow for the continuation of the SMTP session
2101 when TLS is shut down. We test for this by sending a new EHLO. If we
2102 don't get a good response, we don't attempt to pass the socket on. */
2105 if (tls_active >= 0)
2111 ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
2112 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2113 ob->command_timeout);
2117 /* If the socket is successfully passed, we musn't send QUIT (or
2118 indeed anything!) from here. */
2120 if (ok && transport_pass_socket(tblock->name, host->name, host->address,
2121 new_message_id, inblock.sock))
2127 /* If RSET failed and there are addresses left, they get deferred. */
2129 else set_errno(first_addr, errno, msg, DEFER, FALSE);
2133 /* End off tidily with QUIT unless the connection has died or the socket has
2134 been passed to another process. There has been discussion on the net about what
2135 to do after sending QUIT. The wording of the RFC suggests that it is necessary
2136 to wait for a response, but on the other hand, there isn't anything one can do
2137 with an error response, other than log it. Exim used to do that. However,
2138 further discussion suggested that it is positively advantageous not to wait for
2139 the response, but to close the session immediately. This is supposed to move
2140 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
2141 load from the server. (Hosts that are both servers and clients may not see much
2142 difference, of course.) Further discussion indicated that this was safe to do
2143 on Unix systems which have decent implementations of TCP/IP that leave the
2144 connection around for a while (TIME_WAIT) after the application has gone away.
2145 This enables the response sent by the server to be properly ACKed rather than
2146 timed out, as can happen on broken TCP/IP implementations on other OS.
2148 This change is being made on 31-Jul-98. After over a year of trouble-free
2149 operation, the old commented-out code was removed on 17-Sep-99. */
2152 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2160 /* Close the socket, and return the appropriate value, first setting
2161 continue_transport and continue_hostname NULL to prevent any other addresses
2162 that may include the host from trying to re-use a continuation socket. This
2163 works because the NULL setting is passed back to the calling process, and
2164 remote_max_parallel is forced to 1 when delivering over an existing connection,
2166 If all went well and continue_more is set, we shouldn't actually get here if
2167 there are further addresses, as the return above will be taken. However,
2168 writing RSET might have failed, or there may be other addresses whose hosts are
2169 specified in the transports, and therefore not visible at top level, in which
2170 case continue_more won't get set. */
2172 (void)close(inblock.sock);
2173 continue_transport = NULL;
2174 continue_hostname = NULL;
2181 /*************************************************
2182 * Closedown entry point *
2183 *************************************************/
2185 /* This function is called when exim is passed an open smtp channel
2186 from another incarnation, but the message which it has been asked
2187 to deliver no longer exists. The channel is on stdin.
2189 We might do fancy things like looking for another message to send down
2190 the channel, but if the one we sought has gone, it has probably been
2191 delivered by some other process that itself will seek further messages,
2192 so just close down our connection.
2194 Argument: pointer to the transport instance block
2199 smtp_transport_closedown(transport_instance *tblock)
2201 smtp_transport_options_block *ob =
2202 (smtp_transport_options_block *)(tblock->options_block);
2203 smtp_inblock inblock;
2204 smtp_outblock outblock;
2206 uschar inbuffer[4096];
2207 uschar outbuffer[16];
2209 inblock.sock = fileno(stdin);
2210 inblock.buffer = inbuffer;
2211 inblock.buffersize = sizeof(inbuffer);
2212 inblock.ptr = inbuffer;
2213 inblock.ptrend = inbuffer;
2215 outblock.sock = inblock.sock;
2216 outblock.buffersize = sizeof(outbuffer);
2217 outblock.buffer = outbuffer;
2218 outblock.ptr = outbuffer;
2219 outblock.cmd_count = 0;
2220 outblock.authenticating = FALSE;
2222 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2223 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2224 ob->command_timeout);
2225 (void)close(inblock.sock);
2230 /*************************************************
2231 * Prepare addresses for delivery *
2232 *************************************************/
2234 /* This function is called to flush out error settings from previous delivery
2235 attempts to other hosts. It also records whether we got here via an MX record
2236 or not in the more_errno field of the address. We are interested only in
2237 addresses that are still marked DEFER - others may have got delivered to a
2238 previously considered IP address. Set their status to PENDING_DEFER to indicate
2239 which ones are relevant this time.
2242 addrlist the list of addresses
2243 host the host we are delivering to
2245 Returns: the first address for this delivery
2248 static address_item *
2249 prepare_addresses(address_item *addrlist, host_item *host)
2251 address_item *first_addr = NULL;
2253 for (addr = addrlist; addr != NULL; addr = addr->next)
2255 if (addr->transport_return != DEFER) continue;
2256 if (first_addr == NULL) first_addr = addr;
2257 addr->transport_return = PENDING_DEFER;
2258 addr->basic_errno = 0;
2259 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
2260 addr->message = NULL;
2262 addr->cipher = NULL;
2263 addr->peerdn = NULL;
2271 /*************************************************
2272 * Main entry point *
2273 *************************************************/
2275 /* See local README for interface details. As this is a remote transport, it is
2276 given a chain of addresses to be delivered in one connection, if possible. It
2277 always returns TRUE, indicating that each address has its own independent
2278 status set, except if there is a setting up problem, in which case it returns
2282 smtp_transport_entry(
2283 transport_instance *tblock, /* data for this instantiation */
2284 address_item *addrlist) /* addresses we are working on */
2288 int hosts_defer = 0;
2290 int hosts_looked_up = 0;
2291 int hosts_retry = 0;
2292 int hosts_serial = 0;
2293 int hosts_total = 0;
2294 int total_hosts_tried = 0;
2296 BOOL expired = TRUE;
2297 BOOL continuing = continue_hostname != NULL;
2298 uschar *expanded_hosts = NULL;
2300 uschar *tid = string_sprintf("%s transport", tblock->name);
2301 smtp_transport_options_block *ob =
2302 (smtp_transport_options_block *)(tblock->options_block);
2303 host_item *hostlist = addrlist->host_list;
2304 host_item *host = NULL;
2308 debug_printf("%s transport entered\n", tblock->name);
2309 for (addr = addrlist; addr != NULL; addr = addr->next)
2310 debug_printf(" %s\n", addr->address);
2311 if (continuing) debug_printf("already connected to %s [%s]\n",
2312 continue_hostname, continue_host_address);
2315 /* Set the flag requesting that these hosts be added to the waiting
2316 database if the delivery fails temporarily or if we are running with
2317 queue_smtp or a 2-stage queue run. This gets unset for certain
2318 kinds of error, typically those that are specific to the message. */
2320 update_waiting = TRUE;
2322 /* If a host list is not defined for the addresses - they must all have the
2323 same one in order to be passed to a single transport - or if the transport has
2324 a host list with hosts_override set, use the host list supplied with the
2325 transport. It is an error for this not to exist. */
2327 if (hostlist == NULL || (ob->hosts_override && ob->hosts != NULL))
2329 if (ob->hosts == NULL)
2331 addrlist->message = string_sprintf("%s transport called with no hosts set",
2333 addrlist->transport_return = PANIC;
2334 return FALSE; /* Only top address has status */
2337 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
2340 /* If the transport's host list contains no '$' characters, and we are not
2341 randomizing, it is fixed and therefore a chain of hosts can be built once
2342 and for all, and remembered for subsequent use by other calls to this
2343 transport. If, on the other hand, the host list does contain '$', or we are
2344 randomizing its order, we have to rebuild it each time. In the fixed case,
2345 as the hosts string will never be used again, it doesn't matter that we
2346 replace all the : characters with zeros. */
2348 if (ob->hostlist == NULL)
2350 uschar *s = ob->hosts;
2352 if (Ustrchr(s, '$') != NULL)
2354 expanded_hosts = expand_string(s);
2355 if (expanded_hosts == NULL)
2357 addrlist->message = string_sprintf("failed to expand list of hosts "
2358 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
2359 addrlist->transport_return = search_find_defer? DEFER : PANIC;
2360 return FALSE; /* Only top address has status */
2362 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
2363 "\"%s\"\n", s, expanded_hosts);
2367 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
2369 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
2371 /* Check that the expansion yielded something useful. */
2372 if (hostlist == NULL)
2375 string_sprintf("%s transport has empty hosts setting", tblock->name);
2376 addrlist->transport_return = PANIC;
2377 return FALSE; /* Only top address has status */
2380 /* If there was no expansion of hosts, save the host list for
2383 if (expanded_hosts == NULL) ob->hostlist = hostlist;
2386 /* This is not the first time this transport has been run in this delivery;
2387 the host list was built previously. */
2389 else hostlist = ob->hostlist;
2392 /* The host list was supplied with the address. If hosts_randomize is set, we
2393 must sort it into a random order if it did not come from MX records and has not
2394 already been randomized (but don't bother if continuing down an existing
2397 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continuing)
2399 host_item *newlist = NULL;
2400 while (hostlist != NULL)
2402 host_item *h = hostlist;
2403 hostlist = hostlist->next;
2405 h->sort_key = random_number(100);
2407 if (newlist == NULL)
2412 else if (h->sort_key < newlist->sort_key)
2419 host_item *hh = newlist;
2420 while (hh->next != NULL)
2422 if (h->sort_key < hh->next->sort_key) break;
2430 hostlist = addrlist->host_list = newlist;
2434 /* Sort out the default port. */
2436 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
2439 /* For each host-plus-IP-address on the list:
2441 . If this is a continued delivery and the host isn't the one with the
2442 current connection, skip.
2444 . If the status is unusable (i.e. previously failed or retry checked), skip.
2446 . If no IP address set, get the address, either by turning the name into
2447 an address, calling gethostbyname if gethostbyname is on, or by calling
2448 the DNS. The DNS may yield multiple addresses, in which case insert the
2449 extra ones into the list.
2451 . Get the retry data if not previously obtained for this address and set the
2452 field which remembers the state of this address. Skip if the retry time is
2453 not reached. If not, remember whether retry data was found. The retry string
2454 contains both the name and the IP address.
2456 . Scan the list of addresses and mark those whose status is DEFER as
2457 PENDING_DEFER. These are the only ones that will be processed in this cycle
2460 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
2461 Some addresses may be successfully delivered, others may fail, and yet
2462 others may get temporary errors and so get marked DEFER.
2464 . The return from the delivery attempt is OK if a connection was made and a
2465 valid SMTP dialogue was completed. Otherwise it is DEFER.
2467 . If OK, add a "remove" retry item for this host/IPaddress, if any.
2469 . If fail to connect, or other defer state, add a retry item.
2471 . If there are any addresses whose status is still DEFER, carry on to the
2472 next host/IPaddress, unless we have tried the number of hosts given
2473 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
2474 there is some fancy logic for hosts_max_try that means its limit can be
2475 overstepped in some circumstances.
2477 If we get to the end of the list, all hosts have deferred at least one address,
2478 or not reached their retry times. If delay_after_cutoff is unset, it requests a
2479 delivery attempt to those hosts whose last try was before the arrival time of
2480 the current message. To cope with this, we have to go round the loop a second
2481 time. After that, set the status and error data for any addresses that haven't
2482 had it set already. */
2484 for (cutoff_retry = 0; expired &&
2485 cutoff_retry < ((ob->delay_after_cutoff)? 1 : 2);
2488 host_item *nexthost = NULL;
2489 int unexpired_hosts_tried = 0;
2491 for (host = hostlist;
2493 unexpired_hosts_tried < ob->hosts_max_try &&
2494 total_hosts_tried < ob->hosts_max_try_hardlimit;
2500 BOOL serialized = FALSE;
2501 BOOL host_is_expired = FALSE;
2502 BOOL message_defer = FALSE;
2503 BOOL ifchanges = FALSE;
2504 BOOL some_deferred = FALSE;
2505 address_item *first_addr = NULL;
2506 uschar *interface = NULL;
2507 uschar *retry_host_key = NULL;
2508 uschar *retry_message_key = NULL;
2509 uschar *serialize_key = NULL;
2511 /* Default next host is next host. :-) But this can vary if the
2512 hosts_max_try limit is hit (see below). It may also be reset if a host
2513 address is looked up here (in case the host was multihomed). */
2515 nexthost = host->next;
2517 /* If the address hasn't yet been obtained from the host name, look it up
2518 now, unless the host is already marked as unusable. If it is marked as
2519 unusable, it means that the router was unable to find its IP address (in
2520 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
2521 the lookup failed last time. We don't get this far if *all* MX records
2522 point to non-existent hosts; that is treated as a hard error.
2524 We can just skip this host entirely. When the hosts came from the router,
2525 the address will timeout based on the other host(s); when the address is
2526 looked up below, there is an explicit retry record added.
2528 Note that we mustn't skip unusable hosts if the address is not unset; they
2529 may be needed as expired hosts on the 2nd time round the cutoff loop. */
2531 if (host->address == NULL)
2533 int new_port, flags;
2535 uschar *canonical_name;
2537 if (host->status >= hstatus_unusable)
2539 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
2544 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
2546 /* The host name is permitted to have an attached port. Find it, and
2547 strip it from the name. Just remember it for now. */
2549 new_port = host_item_get_port(host);
2551 /* Count hosts looked up */
2555 /* Find by name if so configured, or if it's an IP address. We don't
2556 just copy the IP address, because we need the test-for-local to happen. */
2558 flags = HOST_FIND_BY_A;
2559 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
2560 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
2562 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
2563 rc = host_find_byname(host, NULL, flags, &canonical_name, TRUE);
2565 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
2566 &canonical_name, NULL);
2568 /* Update the host (and any additional blocks, resulting from
2569 multihoming) with a host-specific port, if any. */
2571 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
2573 /* Failure to find the host at this time (usually DNS temporary failure)
2574 is really a kind of routing failure rather than a transport failure.
2575 Therefore we add a retry item of the routing kind, not to stop us trying
2576 to look this name up here again, but to ensure the address gets timed
2577 out if the failures go on long enough. A complete failure at this point
2578 commonly points to a configuration error, but the best action is still
2579 to carry on for the next host. */
2581 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
2583 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
2585 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
2586 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
2587 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
2588 host->status = hstatus_unusable;
2590 for (addr = addrlist; addr != NULL; addr = addr->next)
2592 if (addr->transport_return != DEFER) continue;
2593 addr->basic_errno = ERRNO_UNKNOWNHOST;
2595 string_sprintf("failed to lookup IP address for %s", host->name);
2600 /* If the host is actually the local host, we may have a problem, or
2601 there may be some cunning configuration going on. In the problem case,
2602 log things and give up. The default transport status is already DEFER. */
2604 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
2606 for (addr = addrlist; addr != NULL; addr = addr->next)
2608 addr->basic_errno = 0;
2609 addr->message = string_sprintf("%s transport found host %s to be "
2610 "local", tblock->name, host->name);
2614 } /* End of block for IP address lookup */
2616 /* If this is a continued delivery, we are interested only in the host
2617 which matches the name of the existing open channel. The check is put
2618 here after the local host lookup, in case the name gets expanded as a
2619 result of the lookup. Set expired FALSE, to save the outer loop executing
2622 if (continuing && (Ustrcmp(continue_hostname, host->name) != 0 ||
2623 Ustrcmp(continue_host_address, host->address) != 0))
2626 continue; /* With next host */
2629 /* Reset the default next host in case a multihomed host whose addresses
2630 are not looked up till just above added to the host list. */
2632 nexthost = host->next;
2634 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
2635 domain is in queue_smtp_domains, we don't actually want to attempt any
2636 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
2637 there is a lookup defer in queue_smtp_domains, proceed as if the domain
2638 were not in it. We don't want to hold up all SMTP deliveries! Except when
2639 doing a two-stage queue run, don't do this if forcing. */
2641 if ((!deliver_force || queue_2stage) && (queue_smtp ||
2642 match_isinlist(addrlist->domain, &queue_smtp_domains, 0,
2643 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
2646 for (addr = addrlist; addr != NULL; addr = addr->next)
2648 if (addr->transport_return != DEFER) continue;
2649 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
2651 continue; /* With next host */
2654 /* Count hosts being considered - purely for an intelligent comment
2655 if none are usable. */
2659 /* Set $host and $host address now in case they are needed for the
2660 interface expansion or the serialize_hosts check; they remain set if an
2661 actual delivery happens. */
2663 deliver_host = host->name;
2664 deliver_host_address = host->address;
2666 /* Set up a string for adding to the retry key if the port number is not
2667 the standard SMTP port. A host may have its own port setting that overrides
2670 pistring = string_sprintf(":%d", (host->port == PORT_NONE)?
2672 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
2674 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
2675 string changes upon expansion, we must add it to the key that is used for
2676 retries, because connections to the same host from a different interface
2677 should be treated separately. */
2679 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET : AF_INET6;
2680 if (!smtp_get_interface(ob->interface, host_af, addrlist, &ifchanges,
2683 if (ifchanges) pistring = string_sprintf("%s/%s", pistring, interface);
2685 /* The first time round the outer loop, check the status of the host by
2686 inspecting the retry data. The second time round, we are interested only
2687 in expired hosts that haven't been tried since this message arrived. */
2689 if (cutoff_retry == 0)
2691 /* Ensure the status of the address is set by checking retry data if
2692 necessary. There maybe host-specific retry data (applicable to all
2693 messages) and also data for retries of a specific message at this host.
2694 If either of these retry records are actually read, the keys used are
2695 returned to save recomputing them later. */
2697 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
2698 ob->retry_include_ip_address, &retry_host_key, &retry_message_key);
2700 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
2701 (host->address == NULL)? US"" : host->address, pistring,
2702 (host->status == hstatus_usable)? "usable" :
2703 (host->status == hstatus_unusable)? "unusable" :
2704 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
2706 /* Skip this address if not usable at this time, noting if it wasn't
2707 actually expired, both locally and in the address. */
2709 switch (host->status)
2711 case hstatus_unusable:
2713 setflag(addrlist, af_retry_skipped);
2716 case hstatus_unusable_expired:
2719 case hwhy_retry: hosts_retry++; break;
2720 case hwhy_failed: hosts_fail++; break;
2721 case hwhy_deferred: hosts_defer++; break;
2724 /* If there was a retry message key, implying that previously there
2725 was a message-specific defer, we don't want to update the list of
2726 messages waiting for these hosts. */
2728 if (retry_message_key != NULL) update_waiting = FALSE;
2729 continue; /* With the next host or IP address */
2733 /* Second time round the loop: if the address is set but expired, and
2734 the message is newer than the last try, let it through. */
2738 if (host->address == NULL ||
2739 host->status != hstatus_unusable_expired ||
2740 host->last_try > received_time)
2743 debug_printf("trying expired host %s [%s]%s\n",
2744 host->name, host->address, pistring);
2745 host_is_expired = TRUE;
2748 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
2749 it remains TRUE only if all hosts are expired and none are actually tried.
2754 /* If this host is listed as one to which access must be serialized,
2755 see if another Exim process has a connection to it, and if so, skip
2756 this host. If not, update the database to record our connection to it
2757 and remember this for later deletion. Do not do any of this if we are
2758 sending the message down a pre-existing connection. */
2761 verify_check_this_host(&(ob->serialize_hosts), NULL, host->name,
2762 host->address, NULL) == OK)
2764 serialize_key = string_sprintf("host-serialize-%s", host->name);
2765 if (!enq_start(serialize_key))
2768 debug_printf("skipping host %s because another Exim process "
2769 "is connected to it\n", host->name);
2776 /* OK, we have an IP address that is not waiting for its retry time to
2777 arrive (it might be expired) OR (second time round the loop) we have an
2778 expired host that hasn't been tried since the message arrived. Have a go
2779 at delivering the message to it. First prepare the addresses by flushing
2780 out the result of previous attempts, and finding the first address that
2781 is still to be delivered. */
2783 first_addr = prepare_addresses(addrlist, host);
2785 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
2786 message_id, host->name, host->address, addrlist->address,
2787 (addrlist->next == NULL)? "" : ", ...");
2789 set_process_info("delivering %s to %s [%s] (%s%s)",
2790 message_id, host->name, host->address, addrlist->address,
2791 (addrlist->next == NULL)? "" : ", ...");
2793 /* This is not for real; don't do the delivery. If there are
2794 any remaining hosts, list them. */
2799 set_errno(addrlist, 0, NULL, OK, FALSE);
2800 for (addr = addrlist; addr != NULL; addr = addr->next)
2802 addr->host_used = host;
2803 addr->special_action = '*';
2804 addr->message = US"delivery bypassed by -N option";
2808 debug_printf("*** delivery by %s transport bypassed by -N option\n"
2809 "*** host and remaining hosts:\n", tblock->name);
2810 for (host2 = host; host2 != NULL; host2 = host2->next)
2811 debug_printf(" %s [%s]\n", host2->name,
2812 (host2->address == NULL)? US"unset" : host2->address);
2817 /* This is for real. If the host is expired, we don't count it for
2818 hosts_max_retry. This ensures that all hosts must expire before an address
2819 is timed out, unless hosts_max_try_hardlimit (which protects against
2820 lunatic DNS configurations) is reached.
2822 If the host is not expired and we are about to hit the hosts_max_retry
2823 limit, check to see if there is a subsequent hosts with a different MX
2824 value. If so, make that the next host, and don't count this one. This is a
2825 heuristic to make sure that different MXs do get tried. With a normal kind
2826 of retry rule, they would get tried anyway when the earlier hosts were
2827 delayed, but if the domain has a "retry every time" type of rule - as is
2828 often used for the the very large ISPs, that won't happen. */
2832 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
2836 debug_printf("hosts_max_try limit reached with this host\n");
2837 for (h = host; h != NULL; h = h->next)
2838 if (h->mx != host->mx) break;
2842 unexpired_hosts_tried--;
2843 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
2844 "and will be tried\n");
2848 /* Attempt the delivery. */
2850 total_hosts_tried++;
2851 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
2852 expanded_hosts != NULL, &message_defer, FALSE);
2855 OK => connection made, each address contains its result;
2856 message_defer is set for message-specific defers (when all
2857 recipients are marked defer)
2858 DEFER => there was a non-message-specific delivery problem;
2859 ERROR => there was a problem setting up the arguments for a filter,
2860 or there was a problem with expanding added headers
2863 /* If the result is not OK, there was a non-message-specific problem.
2864 If the result is DEFER, we need to write to the logs saying what happened
2865 for this particular host, except in the case of authentication and TLS
2866 failures, where the log has already been written. If all hosts defer a
2867 general message is written at the end. */
2869 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL &&
2870 first_addr->basic_errno != ERRNO_TLSFAILURE)
2871 write_logs(first_addr, host);
2873 #ifdef EXPERIMENTAL_DBL
2875 dbl_write_defer_log(ob->dbl_host_defer_query, first_addr, host);
2878 /* If STARTTLS was accepted, but there was a failure in setting up the
2879 TLS session (usually a certificate screwup), and the host is not in
2880 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
2881 TLS forcibly turned off. We have to start from scratch with a new SMTP
2882 connection. That's why the retry is done from here, not from within
2883 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
2884 session, so the in-clear transmission after those errors, if permitted,
2885 happens inside smtp_deliver().] */
2888 if (rc == DEFER && first_addr->basic_errno == ERRNO_TLSFAILURE &&
2889 ob->tls_tempfail_tryclear &&
2890 verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
2891 host->address, NULL) != OK)
2893 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
2894 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
2895 first_addr = prepare_addresses(addrlist, host);
2896 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
2897 expanded_hosts != NULL, &message_defer, TRUE);
2898 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
2899 write_logs(first_addr, host);
2900 #ifdef EXPERIMENTAL_DBL
2902 dbl_write_defer_log(ob->dbl_host_defer_query, first_addr, host);
2908 /* Delivery attempt finished */
2910 rs = (rc == OK)? US"OK" : (rc == DEFER)? US"DEFER" : (rc == ERROR)?
2913 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
2914 message_id, host->name, host->address, addrlist->address,
2915 (addrlist->next == NULL)? "" : " (& others)", rs);
2917 /* Release serialization if set up */
2919 if (serialized) enq_end(serialize_key);
2921 /* If the result is DEFER, or if a host retry record is known to exist, we
2922 need to add an item to the retry chain for updating the retry database
2923 at the end of delivery. We only need to add the item to the top address,
2924 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
2925 for any other delivery attempts using the same address. (It is copied into
2926 the unusable tree at the outer level, so even if different address blocks
2927 contain the same address, it still won't get tried again.) */
2929 if (rc == DEFER || retry_host_key != NULL)
2931 int delete_flag = (rc != DEFER)? rf_delete : 0;
2932 if (retry_host_key == NULL)
2934 retry_host_key = ob->retry_include_ip_address?
2935 string_sprintf("T:%S:%s%s", host->name, host->address, pistring) :
2936 string_sprintf("T:%S%s", host->name, pistring);
2939 /* If a delivery of another message over an existing SMTP connection
2940 yields DEFER, we do NOT set up retry data for the host. This covers the
2941 case when there are delays in routing the addresses in the second message
2942 that are so long that the server times out. This is alleviated by not
2943 routing addresses that previously had routing defers when handling an
2944 existing connection, but even so, this case may occur (e.g. if a
2945 previously happily routed address starts giving routing defers). If the
2946 host is genuinely down, another non-continued message delivery will
2947 notice it soon enough. */
2949 if (delete_flag != 0 || !continuing)
2950 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
2952 /* We may have tried an expired host, if its retry time has come; ensure
2953 the status reflects the expiry for the benefit of any other addresses. */
2957 host->status = (host_is_expired)?
2958 hstatus_unusable_expired : hstatus_unusable;
2959 host->why = hwhy_deferred;
2963 /* If message_defer is set (host was OK, but every recipient got deferred
2964 because of some message-specific problem), or if that had happened
2965 previously so that a message retry key exists, add an appropriate item
2966 to the retry chain. Note that if there was a message defer but now there is
2967 a host defer, the message defer record gets deleted. That seems perfectly
2968 reasonable. Also, stop the message from being remembered as waiting
2969 for specific hosts. */
2971 if (message_defer || retry_message_key != NULL)
2973 int delete_flag = message_defer? 0 : rf_delete;
2974 if (retry_message_key == NULL)
2976 retry_message_key = ob->retry_include_ip_address?
2977 string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
2979 string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
2981 retry_add_item(addrlist, retry_message_key,
2982 rf_message | rf_host | delete_flag);
2983 update_waiting = FALSE;
2986 /* Any return other than DEFER (that is, OK or ERROR) means that the
2987 addresses have got their final statuses filled in for this host. In the OK
2988 case, see if any of them are deferred. */
2992 for (addr = addrlist; addr != NULL; addr = addr->next)
2994 if (addr->transport_return == DEFER)
2996 some_deferred = TRUE;
3002 /* If no addresses deferred or the result was ERROR, return. We do this for
3003 ERROR because a failing filter set-up or add_headers expansion is likely to
3004 fail for any host we try. */
3006 if (rc == ERROR || (rc == OK && !some_deferred))
3008 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3009 return TRUE; /* Each address has its status */
3012 /* If the result was DEFER or some individual addresses deferred, let
3013 the loop run to try other hosts with the deferred addresses, except for the
3014 case when we were trying to deliver down an existing channel and failed.
3015 Don't try any other hosts in this case. */
3017 if (continuing) break;
3019 /* If the whole delivery, or some individual addresses, were deferred and
3020 there are more hosts that could be tried, do not count this host towards
3021 the hosts_max_try limit if the age of the message is greater than the
3022 maximum retry time for this host. This means we may try try all hosts,
3023 ignoring the limit, when messages have been around for some time. This is
3024 important because if we don't try all hosts, the address will never time
3025 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
3027 if ((rc == DEFER || some_deferred) && nexthost != NULL)
3030 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
3032 if (retry != NULL && retry->rules != NULL)
3034 retry_rule *last_rule;
3035 for (last_rule = retry->rules;
3036 last_rule->next != NULL;
3037 last_rule = last_rule->next);
3038 timedout = time(NULL) - received_time > last_rule->timeout;
3040 else timedout = TRUE; /* No rule => timed out */
3044 unexpired_hosts_tried--;
3045 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
3046 "hosts_max_try (message older than host's retry time)\n");
3049 } /* End of loop for trying multiple hosts. */
3051 /* This is the end of the loop that repeats iff expired is TRUE and
3052 ob->delay_after_cutoff is FALSE. The second time round we will
3053 try those hosts that haven't been tried since the message arrived. */
3057 debug_printf("all IP addresses skipped or deferred at least one address\n");
3058 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
3059 debug_printf("retrying IP addresses not tried since message arrived\n");
3064 /* Get here if all IP addresses are skipped or defer at least one address. In
3065 MUA wrapper mode, this will happen only for connection or other non-message-
3066 specific failures. Force the delivery status for all addresses to FAIL. */
3070 for (addr = addrlist; addr != NULL; addr = addr->next)
3071 addr->transport_return = FAIL;
3075 /* In the normal, non-wrapper case, add a standard message to each deferred
3076 address if there hasn't been an error, that is, if it hasn't actually been
3077 tried this time. The variable "expired" will be FALSE if any deliveries were
3078 actually tried, or if there was at least one host that was not expired. That
3079 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
3080 a delivery has been tried, an error code will be set, and the failing of the
3081 message is handled by the retry code later.
3083 If queue_smtp is set, or this transport was called to send a subsequent message
3084 down an existing TCP/IP connection, and something caused the host not to be
3085 found, we end up here, but can detect these cases and handle them specially. */
3087 for (addr = addrlist; addr != NULL; addr = addr->next)
3089 /* If host is not NULL, it means that we stopped processing the host list
3090 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
3091 means we need to behave as if some hosts were skipped because their retry
3092 time had not come. Specifically, this prevents the address from timing out.
3093 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
3094 hosts were tried. */
3098 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
3101 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
3102 "hosts were tried\n");
3107 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
3108 setflag(addr, af_retry_skipped);
3112 if (queue_smtp) /* no deliveries attempted */
3114 addr->transport_return = DEFER;
3115 addr->basic_errno = 0;
3116 addr->message = US"SMTP delivery explicitly queued";
3119 else if (addr->transport_return == DEFER &&
3120 (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0) &&
3121 addr->message == NULL)
3123 addr->basic_errno = ERRNO_HRETRY;
3124 if (continue_hostname != NULL)
3126 addr->message = US"no host found for existing SMTP connection";
3130 setflag(addr, af_pass_message); /* This is not a security risk */
3131 addr->message = (ob->delay_after_cutoff)?
3132 US"retry time not reached for any host after a long failure period" :
3133 US"all hosts have been failing for a long time and were last tried "
3134 "after this message arrived";
3136 /* If we are already using fallback hosts, or there are no fallback hosts
3137 defined, convert the result to FAIL to cause a bounce. */
3139 if (addr->host_list == addr->fallback_hosts ||
3140 addr->fallback_hosts == NULL)
3141 addr->transport_return = FAIL;
3145 if (hosts_retry == hosts_total)
3146 addr->message = US"retry time not reached for any host";
3147 else if (hosts_fail == hosts_total)
3148 addr->message = US"all host address lookups failed permanently";
3149 else if (hosts_defer == hosts_total)
3150 addr->message = US"all host address lookups failed temporarily";
3151 else if (hosts_serial == hosts_total)
3152 addr->message = US"connection limit reached for all hosts";
3153 else if (hosts_fail+hosts_defer == hosts_total)
3154 addr->message = US"all host address lookups failed";
3155 else addr->message = US"some host address lookups failed and retry time "
3156 "not reached for other hosts or connection limit reached";
3161 /* Update the database which keeps information about which messages are waiting
3162 for which hosts to become available. For some message-specific errors, the
3163 update_waiting flag is turned off because we don't want follow-on deliveries in
3166 if (update_waiting) transport_update_waiting(hostlist, tblock->name);
3170 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3172 return TRUE; /* Each address has its status */
3175 /* End of transport/smtp.c */
git://git.exim.org / users / jgh / exim.git / blob