1 /* $Cambridge: exim/src/src/transports/smtp.c,v 1.38 2007/09/28 12:21:57 tom Exp $ */
3 /*************************************************
4 * Exim - an Internet mail transport agent *
5 *************************************************/
7 /* Copyright (c) University of Cambridge 1995 - 2007 */
8 /* See the file NOTICE for conditions of use and distribution. */
14 #define PENDING_DEFER (PENDING + DEFER)
15 #define PENDING_OK (PENDING + OK)
18 /* Options specific to the smtp transport. This transport also supports LMTP
19 over TCP/IP. The options must be in alphabetic order (note that "_" comes
20 before the lower case letters). Some live in the transport_instance block so as
21 to be publicly visible; these are flagged with opt_public. */
23 optionlist smtp_transport_options[] = {
24 { "address_retry_include_sender", opt_bool,
25 (void *)offsetof(smtp_transport_options_block, address_retry_include_sender) },
26 { "allow_localhost", opt_bool,
27 (void *)offsetof(smtp_transport_options_block, allow_localhost) },
28 { "authenticated_sender", opt_stringptr,
29 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
30 { "authenticated_sender_force", opt_bool,
31 (void *)offsetof(smtp_transport_options_block, authenticated_sender_force) },
32 { "command_timeout", opt_time,
33 (void *)offsetof(smtp_transport_options_block, command_timeout) },
34 { "connect_timeout", opt_time,
35 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
36 { "connection_max_messages", opt_int | opt_public,
37 (void *)offsetof(transport_instance, connection_max_messages) },
38 { "data_timeout", opt_time,
39 (void *)offsetof(smtp_transport_options_block, data_timeout) },
40 { "delay_after_cutoff", opt_bool,
41 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
42 #ifdef EXPERIMENTAL_DOMAINKEYS
43 { "dk_canon", opt_stringptr,
44 (void *)offsetof(smtp_transport_options_block, dk_canon) },
45 { "dk_domain", opt_stringptr,
46 (void *)offsetof(smtp_transport_options_block, dk_domain) },
47 { "dk_headers", opt_stringptr,
48 (void *)offsetof(smtp_transport_options_block, dk_headers) },
49 { "dk_private_key", opt_stringptr,
50 (void *)offsetof(smtp_transport_options_block, dk_private_key) },
51 { "dk_selector", opt_stringptr,
52 (void *)offsetof(smtp_transport_options_block, dk_selector) },
53 { "dk_strict", opt_stringptr,
54 (void *)offsetof(smtp_transport_options_block, dk_strict) },
56 #ifdef EXPERIMENTAL_DKIM
57 { "dkim_canon", opt_stringptr,
58 (void *)offsetof(smtp_transport_options_block, dkim_canon) },
59 { "dkim_domain", opt_stringptr,
60 (void *)offsetof(smtp_transport_options_block, dkim_domain) },
61 { "dkim_private_key", opt_stringptr,
62 (void *)offsetof(smtp_transport_options_block, dkim_private_key) },
63 { "dkim_selector", opt_stringptr,
64 (void *)offsetof(smtp_transport_options_block, dkim_selector) },
65 { "dkim_sign_headers", opt_stringptr,
66 (void *)offsetof(smtp_transport_options_block, dkim_sign_headers) },
67 { "dkim_strict", opt_stringptr,
68 (void *)offsetof(smtp_transport_options_block, dkim_strict) },
70 { "dns_qualify_single", opt_bool,
71 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
72 { "dns_search_parents", opt_bool,
73 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
74 { "fallback_hosts", opt_stringptr,
75 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
76 { "final_timeout", opt_time,
77 (void *)offsetof(smtp_transport_options_block, final_timeout) },
78 { "gethostbyname", opt_bool,
79 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
81 { "gnutls_require_kx", opt_stringptr,
82 (void *)offsetof(smtp_transport_options_block, gnutls_require_kx) },
83 { "gnutls_require_mac", opt_stringptr,
84 (void *)offsetof(smtp_transport_options_block, gnutls_require_mac) },
85 { "gnutls_require_protocols", opt_stringptr,
86 (void *)offsetof(smtp_transport_options_block, gnutls_require_proto) },
88 { "helo_data", opt_stringptr,
89 (void *)offsetof(smtp_transport_options_block, helo_data) },
90 { "hosts", opt_stringptr,
91 (void *)offsetof(smtp_transport_options_block, hosts) },
92 { "hosts_avoid_esmtp", opt_stringptr,
93 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
94 { "hosts_avoid_pipelining", opt_stringptr,
95 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
97 { "hosts_avoid_tls", opt_stringptr,
98 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
100 { "hosts_max_try", opt_int,
101 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
102 { "hosts_max_try_hardlimit", opt_int,
103 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
105 { "hosts_nopass_tls", opt_stringptr,
106 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
108 { "hosts_override", opt_bool,
109 (void *)offsetof(smtp_transport_options_block, hosts_override) },
110 { "hosts_randomize", opt_bool,
111 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
112 { "hosts_require_auth", opt_stringptr,
113 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
115 { "hosts_require_tls", opt_stringptr,
116 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
118 { "hosts_try_auth", opt_stringptr,
119 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
120 { "interface", opt_stringptr,
121 (void *)offsetof(smtp_transport_options_block, interface) },
122 { "keepalive", opt_bool,
123 (void *)offsetof(smtp_transport_options_block, keepalive) },
124 { "lmtp_ignore_quota", opt_bool,
125 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
126 { "max_rcpt", opt_int | opt_public,
127 (void *)offsetof(transport_instance, max_addresses) },
128 { "multi_domain", opt_bool | opt_public,
129 (void *)offsetof(transport_instance, multi_domain) },
130 { "port", opt_stringptr,
131 (void *)offsetof(smtp_transport_options_block, port) },
132 { "protocol", opt_stringptr,
133 (void *)offsetof(smtp_transport_options_block, protocol) },
134 { "retry_include_ip_address", opt_bool,
135 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
136 { "serialize_hosts", opt_stringptr,
137 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
138 { "size_addition", opt_int,
139 (void *)offsetof(smtp_transport_options_block, size_addition) }
141 ,{ "tls_certificate", opt_stringptr,
142 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
143 { "tls_crl", opt_stringptr,
144 (void *)offsetof(smtp_transport_options_block, tls_crl) },
145 { "tls_privatekey", opt_stringptr,
146 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
147 { "tls_require_ciphers", opt_stringptr,
148 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
149 { "tls_tempfail_tryclear", opt_bool,
150 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
151 { "tls_verify_certificates", opt_stringptr,
152 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) }
156 /* Size of the options list. An extern variable has to be used so that its
157 address can appear in the tables drtables.c. */
159 int smtp_transport_options_count =
160 sizeof(smtp_transport_options)/sizeof(optionlist);
162 /* Default private options block for the smtp transport. */
164 smtp_transport_options_block smtp_transport_option_defaults = {
166 NULL, /* fallback_hosts */
168 NULL, /* fallback_hostlist */
169 NULL, /* authenticated_sender */
170 US"$primary_hostname", /* helo_data */
171 NULL, /* interface */
173 US"smtp", /* protocol */
174 NULL, /* serialize_hosts */
175 NULL, /* hosts_try_auth */
176 NULL, /* hosts_require_auth */
177 NULL, /* hosts_require_tls */
178 NULL, /* hosts_avoid_tls */
179 NULL, /* hosts_avoid_pipelining */
180 NULL, /* hosts_avoid_esmtp */
181 NULL, /* hosts_nopass_tls */
182 5*60, /* command_timeout */
183 5*60, /* connect_timeout; shorter system default overrides */
184 5*60, /* data timeout */
185 10*60, /* final timeout */
186 1024, /* size_addition */
187 5, /* hosts_max_try */
188 50, /* hosts_max_try_hardlimit */
189 TRUE, /* address_retry_include_sender */
190 FALSE, /* allow_localhost */
191 FALSE, /* authenticated_sender_force */
192 FALSE, /* gethostbyname */
193 TRUE, /* dns_qualify_single */
194 FALSE, /* dns_search_parents */
195 TRUE, /* delay_after_cutoff */
196 FALSE, /* hosts_override */
197 FALSE, /* hosts_randomize */
198 TRUE, /* keepalive */
199 FALSE, /* lmtp_ignore_quota */
200 TRUE /* retry_include_ip_address */
202 ,NULL, /* tls_certificate */
204 NULL, /* tls_privatekey */
205 NULL, /* tls_require_ciphers */
206 NULL, /* gnutls_require_kx */
207 NULL, /* gnutls_require_mac */
208 NULL, /* gnutls_require_proto */
209 NULL, /* tls_verify_certificates */
210 TRUE /* tls_tempfail_tryclear */
212 #ifdef EXPERIMENTAL_DOMAINKEYS
213 ,NULL, /* dk_canon */
214 NULL, /* dk_domain */
215 NULL, /* dk_headers */
216 NULL, /* dk_private_key */
217 NULL, /* dk_selector */
220 #ifdef EXPERIMENTAL_DKIM
221 ,NULL, /* dkim_canon */
222 NULL, /* dkim_domain */
223 NULL, /* dkim_private_key */
224 NULL, /* dkim_selector */
225 NULL, /* dkim_sign_headers */
226 NULL /* dkim_strict */
233 static uschar *smtp_command; /* Points to last cmd for error messages */
234 static uschar *mail_command; /* Points to MAIL cmd for error messages */
235 static BOOL update_waiting; /* TRUE to update the "wait" database */
238 /*************************************************
239 * Setup entry point *
240 *************************************************/
242 /* This function is called when the transport is about to be used,
243 but before running it in a sub-process. It is used for two things:
245 (1) To set the fallback host list in addresses, when delivering.
246 (2) To pass back the interface, port, protocol, and other options, for use
247 during callout verification.
250 tblock pointer to the transport instance block
251 addrlist list of addresses about to be transported
252 tf if not NULL, pointer to block in which to return options
253 uid the uid that will be set (not used)
254 gid the gid that will be set (not used)
255 errmsg place for error message (not used)
257 Returns: OK always (FAIL, DEFER not used)
261 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
262 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
264 smtp_transport_options_block *ob =
265 (smtp_transport_options_block *)(tblock->options_block);
267 errmsg = errmsg; /* Keep picky compilers happy */
271 /* Pass back options if required. This interface is getting very messy. */
275 tf->interface = ob->interface;
277 tf->protocol = ob->protocol;
278 tf->hosts = ob->hosts;
279 tf->hosts_override = ob->hosts_override;
280 tf->hosts_randomize = ob->hosts_randomize;
281 tf->gethostbyname = ob->gethostbyname;
282 tf->qualify_single = ob->dns_qualify_single;
283 tf->search_parents = ob->dns_search_parents;
284 tf->helo_data = ob->helo_data;
287 /* Set the fallback host list for all the addresses that don't have fallback
288 host lists, provided that the local host wasn't present in the original host
291 if (!testflag(addrlist, af_local_host_removed))
293 for (; addrlist != NULL; addrlist = addrlist->next)
294 if (addrlist->fallback_hosts == NULL)
295 addrlist->fallback_hosts = ob->fallback_hostlist;
303 /*************************************************
304 * Initialization entry point *
305 *************************************************/
307 /* Called for each instance, after its options have been read, to
308 enable consistency checks to be done, or anything else that needs
311 Argument: pointer to the transport instance block
316 smtp_transport_init(transport_instance *tblock)
318 smtp_transport_options_block *ob =
319 (smtp_transport_options_block *)(tblock->options_block);
321 /* Retry_use_local_part defaults FALSE if unset */
323 if (tblock->retry_use_local_part == TRUE_UNSET)
324 tblock->retry_use_local_part = FALSE;
326 /* Set the default port according to the protocol */
328 if (ob->port == NULL)
329 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" : US"smtp";
331 /* Set up the setup entry point, to be called before subprocesses for this
334 tblock->setup = smtp_transport_setup;
336 /* Complain if any of the timeouts are zero. */
338 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
339 ob->final_timeout <= 0)
340 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
341 "command, data, or final timeout value is zero for %s transport",
344 /* If hosts_override is set and there are local hosts, set the global
345 flag that stops verify from showing router hosts. */
347 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
349 /* If there are any fallback hosts listed, build a chain of host items
350 for them, but do not do any lookups at this time. */
352 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
359 /*************************************************
360 * Set delivery info into all active addresses *
361 *************************************************/
363 /* Only addresses whose status is >= PENDING are relevant. A lesser
364 status means that an address is not currently being processed.
367 addrlist points to a chain of addresses
368 errno_value to put in each address's errno field
369 msg to put in each address's message field
370 rc to put in each address's transport_return field
371 pass_message if TRUE, set the "pass message" flag in the address
373 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
374 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
375 this particular type of timeout.
381 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
386 if (errno_value == ERRNO_CONNECTTIMEOUT)
388 errno_value = ETIMEDOUT;
389 orvalue = RTEF_CTOUT;
391 for (addr = addrlist; addr != NULL; addr = addr->next)
393 if (addr->transport_return < PENDING) continue;
394 addr->basic_errno = errno_value;
395 addr->more_errno |= orvalue;
399 if (pass_message) setflag(addr, af_pass_message);
401 addr->transport_return = rc;
407 /*************************************************
408 * Check an SMTP response *
409 *************************************************/
411 /* This function is given an errno code and the SMTP response buffer
412 to analyse, together with the host identification for generating messages. It
413 sets an appropriate message and puts the first digit of the response code into
414 the yield variable. If no response was actually read, a suitable digit is
418 host the current host, to get its name for messages
419 errno_value pointer to the errno value
420 more_errno from the top address for use with ERRNO_FILTER_FAIL
421 buffer the SMTP response buffer
422 yield where to put a one-digit SMTP response code
423 message where to put an errror message
424 pass_message set TRUE if message is an SMTP response
426 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
429 static BOOL check_response(host_item *host, int *errno_value, int more_errno,
430 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
434 if (smtp_use_pipelining &&
435 (Ustrcmp(smtp_command, "MAIL") == 0 ||
436 Ustrcmp(smtp_command, "RCPT") == 0 ||
437 Ustrcmp(smtp_command, "DATA") == 0))
440 *yield = '4'; /* Default setting is to give a temporary error */
442 /* Handle response timeout */
444 if (*errno_value == ETIMEDOUT)
446 *message = US string_sprintf("SMTP timeout while connected to %s [%s] "
447 "after %s%s", host->name, host->address, pl, smtp_command);
448 if (transport_count > 0)
449 *message = US string_sprintf("%s (%d bytes written)", *message,
454 /* Handle malformed SMTP response */
456 if (*errno_value == ERRNO_SMTPFORMAT)
458 uschar *malfresp = string_printing(buffer);
459 while (isspace(*malfresp)) malfresp++;
461 *message = string_sprintf("Malformed SMTP reply (an empty line) from "
462 "%s [%s] in response to %s%s", host->name, host->address, pl,
465 *message = string_sprintf("Malformed SMTP reply from %s [%s] in response "
466 "to %s%s: %s", host->name, host->address, pl, smtp_command, malfresp);
470 /* Handle a failed filter process error; can't send QUIT as we mustn't
473 if (*errno_value == ERRNO_FILTER_FAIL)
475 *message = US string_sprintf("transport filter process failed (%d)%s",
477 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
481 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
484 if (*errno_value == ERRNO_CHHEADER_FAIL)
487 US string_sprintf("failed to expand headers_add or headers_remove: %s",
488 expand_string_message);
492 /* Handle failure to write a complete data block */
494 if (*errno_value == ERRNO_WRITEINCOMPLETE)
496 *message = US string_sprintf("failed to write a data block");
500 /* Handle error responses from the remote mailer. */
504 uschar *s = string_printing(buffer);
505 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
506 "host %s [%s]: %s", pl, smtp_command, host->name, host->address, s);
507 *pass_message = TRUE;
512 /* No data was read. If there is no errno, this must be the EOF (i.e.
513 connection closed) case, which causes deferral. An explicit connection reset
514 error has the same effect. Otherwise, put the host's identity in the message,
515 leaving the errno value to be interpreted as well. In all cases, we have to
516 assume the connection is now dead. */
518 if (*errno_value == 0 || *errno_value == ECONNRESET)
520 *errno_value = ERRNO_SMTPCLOSED;
521 *message = US string_sprintf("Remote host %s [%s] closed connection "
522 "in response to %s%s", host->name, host->address, pl, smtp_command);
524 else *message = US string_sprintf("%s [%s]", host->name, host->address);
531 /*************************************************
532 * Write error message to logs *
533 *************************************************/
535 /* This writes to the main log and to the message log.
538 addr the address item containing error information
539 host the current host
545 write_logs(address_item *addr, host_item *host)
547 if (addr->message != NULL)
549 uschar *message = addr->message;
550 if (addr->basic_errno > 0)
551 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
552 log_write(0, LOG_MAIN, "%s", message);
553 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
558 ((log_extra_selector & LX_outgoing_port) != 0)?
559 string_sprintf("%s [%s]:%d", host->name, host->address,
560 (host->port == PORT_NONE)? 25 : host->port)
562 string_sprintf("%s [%s]", host->name, host->address);
563 log_write(0, LOG_MAIN, "%s %s", msg, strerror(addr->basic_errno));
564 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), msg,
565 strerror(addr->basic_errno));
571 /*************************************************
572 * Synchronize SMTP responses *
573 *************************************************/
575 /* This function is called from smtp_deliver() to receive SMTP responses from
576 the server, and match them up with the commands to which they relate. When
577 PIPELINING is not in use, this function is called after every command, and is
578 therefore somewhat over-engineered, but it is simpler to use a single scheme
579 that works both with and without PIPELINING instead of having two separate sets
582 The set of commands that are buffered up with pipelining may start with MAIL
583 and may end with DATA; in between are RCPT commands that correspond to the
584 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
585 etc.) are never buffered.
587 Errors after MAIL or DATA abort the whole process leaving the response in the
588 buffer. After MAIL, pending responses are flushed, and the original command is
589 re-instated in big_buffer for error messages. For RCPT commands, the remote is
590 permitted to reject some recipient addresses while accepting others. However
591 certain errors clearly abort the whole process. Set the value in
592 transport_return to PENDING_OK if the address is accepted. If there is a
593 subsequent general error, it will get reset accordingly. If not, it will get
594 converted to OK at the end.
597 addrlist the complete address list
598 include_affixes TRUE if affixes include in RCPT
599 sync_addr ptr to the ptr of the one to start scanning at (updated)
600 host the host we are connected to
601 count the number of responses to read
603 include_sender true if 4xx retry is to include the sender it its key
604 pending_MAIL true if the first response is for MAIL
605 pending_DATA 0 if last command sent was not DATA
606 +1 if previously had a good recipient
607 -1 if not previously had a good recipient
608 inblock incoming SMTP block
609 timeout timeout value
610 buffer buffer for reading response
611 buffsize size of buffer
613 Returns: 3 if at least one address had 2xx and one had 5xx
614 2 if at least one address had 5xx but none had 2xx
615 1 if at least one host had a 2xx response, but none had 5xx
616 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
617 -1 timeout while reading RCPT response
618 -2 I/O or other non-response error for RCPT
619 -3 DATA or MAIL failed - errno and buffer set
623 sync_responses(address_item *addrlist, BOOL include_affixes,
624 address_item **sync_addr, host_item *host, int count,
625 BOOL address_retry_include_sender, BOOL pending_MAIL,
626 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
629 address_item *addr = *sync_addr;
632 /* Handle the response for a MAIL command. On error, reinstate the original
633 command in big_buffer for error message use, and flush any further pending
634 responses before returning, except after I/O errors and timeouts. */
639 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
641 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
642 if (errno == 0 && buffer[0] != 0)
644 uschar flushbuffer[4096];
646 if (buffer[0] == '4')
648 save_errno = ERRNO_MAIL4XX;
649 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
653 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
655 && (errno != 0 || flushbuffer[0] == 0))
664 if (pending_DATA) count--; /* Number of RCPT responses to come */
666 /* Read and handle the required number of RCPT responses, matching each one up
667 with an address by scanning for the next address whose status is PENDING_DEFER.
672 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
674 /* The address was accepted */
676 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
679 addr->transport_return = PENDING_OK;
681 /* If af_dr_retry_exists is set, there was a routing delay on this address;
682 ensure that any address-specific retry record is expunged. We do this both
683 for the basic key and for the version that also includes the sender. */
685 if (testflag(addr, af_dr_retry_exists))
687 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
689 retry_add_item(addr, altkey, rf_delete);
690 retry_add_item(addr, addr->address_retry_key, rf_delete);
694 /* Timeout while reading the response */
696 else if (errno == ETIMEDOUT)
698 int save_errno = errno;
699 uschar *message = string_sprintf("SMTP timeout while connected to %s [%s] "
700 "after RCPT TO:<%s>", host->name, host->address,
701 transport_rcpt_address(addr, include_affixes));
702 set_errno(addrlist, save_errno, message, DEFER, FALSE);
703 retry_add_item(addr, addr->address_retry_key, 0);
704 update_waiting = FALSE;
708 /* Handle other errors in obtaining an SMTP response by returning -1. This
709 will cause all the addresses to be deferred. Restore the SMTP command in
710 big_buffer for which we are checking the response, so the error message
713 else if (errno != 0 || buffer[0] == 0)
715 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
716 transport_rcpt_address(addr, include_affixes));
720 /* Handle SMTP permanent and temporary response codes. */
725 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
726 "host %s [%s]: %s", transport_rcpt_address(addr, include_affixes),
727 host->name, host->address, string_printing(buffer));
728 setflag(addr, af_pass_message);
729 deliver_msglog("%s %s\n", tod_stamp(tod_log), addr->message);
731 /* The response was 5xx */
733 if (buffer[0] == '5')
735 addr->transport_return = FAIL;
739 /* The response was 4xx */
743 addr->transport_return = DEFER;
744 addr->basic_errno = ERRNO_RCPT4XX;
745 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
747 /* Log temporary errors if there are more hosts to be tried. */
749 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", addr->message);
751 /* Do not put this message on the list of those waiting for specific
752 hosts, as otherwise it is likely to be tried too often. */
754 update_waiting = FALSE;
756 /* Add a retry item for the address so that it doesn't get tried again
757 too soon. If address_retry_include_sender is true, add the sender address
760 if (address_retry_include_sender)
762 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
764 retry_add_item(addr, altkey, 0);
766 else retry_add_item(addr, addr->address_retry_key, 0);
769 } /* Loop for next RCPT response */
771 /* Update where to start at for the next block of responses, unless we
772 have already handled all the addresses. */
774 if (addr != NULL) *sync_addr = addr->next;
776 /* Handle a response to DATA. If we have not had any good recipients, either
777 previously or in this block, the response is ignored. */
779 if (pending_DATA != 0 &&
780 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
785 if (pending_DATA > 0 || (yield & 1) != 0)
787 if (errno == 0 && buffer[0] == '4')
789 errno = ERRNO_DATA4XX;
790 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
794 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
795 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
796 "is in use and there were no good recipients\n", msg);
799 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
800 present) received 3xx. If any RCPTs were handled and yielded anything other
801 than 4xx, yield will be set non-zero. */
808 /*************************************************
809 * Deliver address list to given host *
810 *************************************************/
812 /* If continue_hostname is not null, we get here only when continuing to
813 deliver down an existing channel. The channel was passed as the standard
814 input. TLS is never active on a passed channel; the previous process always
815 closes it down before passing the connection on.
817 Otherwise, we have to make a connection to the remote host, and do the
818 initial protocol exchange.
820 When running as an MUA wrapper, if the sender or any recipient is rejected,
821 temporarily or permanently, we force failure for all recipients.
824 addrlist chain of potential addresses to deliver; only those whose
825 transport_return field is set to PENDING_DEFER are currently
826 being processed; others should be skipped - they have either
827 been delivered to an earlier host or IP address, or been
828 failed by one of them.
829 host host to deliver to
830 host_af AF_INET or AF_INET6
831 port default TCP/IP port to use, in host byte order
832 interface interface to bind to, or NULL
833 tblock transport instance block
834 copy_host TRUE if host set in addr->host_used must be copied, because
835 it is specific to this call of the transport
836 message_defer set TRUE if yield is OK, but all addresses were deferred
837 because of a non-recipient, non-host failure, that is, a
838 4xx response to MAIL FROM, DATA, or ".". This is a defer
839 that is specific to the message.
840 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
841 a second attempt after TLS initialization fails
843 Returns: OK - the connection was made and the delivery attempted;
844 the result for each address is in its data block.
845 DEFER - the connection could not be made, or something failed
846 while setting up the SMTP session, or there was a
847 non-message-specific error, such as a timeout.
848 ERROR - a filter command is specified for this transport,
849 and there was a problem setting it up; OR helo_data
850 or add_headers or authenticated_sender is specified
851 for this transport, and the string failed to expand
855 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
856 uschar *interface, transport_instance *tblock, BOOL copy_host,
857 BOOL *message_defer, BOOL suppress_tls)
860 address_item *sync_addr;
861 address_item *first_addr = addrlist;
866 time_t start_delivery_time = time(NULL);
867 smtp_transport_options_block *ob =
868 (smtp_transport_options_block *)(tblock->options_block);
869 BOOL lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
871 BOOL send_rset = TRUE;
872 BOOL send_quit = TRUE;
873 BOOL setting_up = TRUE;
874 BOOL completed_address = FALSE;
877 BOOL pass_message = FALSE;
878 smtp_inblock inblock;
879 smtp_outblock outblock;
880 int max_rcpt = tblock->max_addresses;
881 uschar *igquotstr = US"";
882 uschar *local_authenticated_sender = authenticated_sender;
883 uschar *helo_data = NULL;
884 uschar *message = NULL;
885 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
888 uschar inbuffer[4096];
889 uschar outbuffer[1024];
891 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
893 *message_defer = FALSE;
894 smtp_command = US"initial connection";
895 if (max_rcpt == 0) max_rcpt = 999999;
897 /* Set up the buffer for reading SMTP response packets. */
899 inblock.buffer = inbuffer;
900 inblock.buffersize = sizeof(inbuffer);
901 inblock.ptr = inbuffer;
902 inblock.ptrend = inbuffer;
904 /* Set up the buffer for holding SMTP commands while pipelining */
906 outblock.buffer = outbuffer;
907 outblock.buffersize = sizeof(outbuffer);
908 outblock.ptr = outbuffer;
909 outblock.cmd_count = 0;
910 outblock.authenticating = FALSE;
912 /* Reset the parameters of a TLS session. */
917 /* If an authenticated_sender override has been specified for this transport
918 instance, expand it. If the expansion is forced to fail, and there was already
919 an authenticated_sender for this message, the original value will be used.
920 Other expansion failures are serious. An empty result is ignored, but there is
921 otherwise no check - this feature is expected to be used with LMTP and other
922 cases where non-standard addresses (e.g. without domains) might be required. */
924 if (ob->authenticated_sender != NULL)
926 uschar *new = expand_string(ob->authenticated_sender);
929 if (!expand_string_forcedfail)
931 uschar *message = string_sprintf("failed to expand "
932 "authenticated_sender: %s", expand_string_message);
933 set_errno(addrlist, 0, message, DEFER, FALSE);
937 else if (new[0] != 0) local_authenticated_sender = new;
940 /* Make a connection to the host if this isn't a continued delivery, and handle
941 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
942 specially so they can be identified for retries. */
944 if (continue_hostname == NULL)
946 inblock.sock = outblock.sock =
947 smtp_connect(host, host_af, port, interface, ob->connect_timeout,
948 ob->keepalive); /* This puts port into host->port */
950 if (inblock.sock < 0)
952 set_errno(addrlist, (errno == ETIMEDOUT)? ERRNO_CONNECTTIMEOUT : errno,
957 /* Expand the greeting message while waiting for the initial response. (Makes
958 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
959 delayed till here so that $sending_interface and $sending_port are set. */
961 helo_data = expand_string(ob->helo_data);
963 /* The first thing is to wait for an initial OK response. The dreaded "goto"
964 is nevertheless a reasonably clean way of programming this kind of logic,
965 where you want to escape on any error. */
967 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
968 ob->command_timeout)) goto RESPONSE_FAILED;
970 /* Now check if the helo_data expansion went well, and sign off cleanly if it
973 if (helo_data == NULL)
975 uschar *message = string_sprintf("failed to expand helo_data: %s",
976 expand_string_message);
977 set_errno(addrlist, 0, message, DEFER, FALSE);
982 /** Debugging without sending a message
983 addrlist->transport_return = DEFER;
987 /* Errors that occur after this point follow an SMTP command, which is
988 left in big_buffer by smtp_write_command() for use in error messages. */
990 smtp_command = big_buffer;
992 /* Tell the remote who we are...
994 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
995 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
996 greeting is of this form. The assumption was that the far end supports it
997 properly... but experience shows that there are some that give 5xx responses,
998 even though the banner includes "ESMTP" (there's a bloody-minded one that
999 says "ESMTP not spoken here"). Cope with that case.
1001 September 2000: Time has passed, and it seems reasonable now to always send
1002 EHLO at the start. It is also convenient to make the change while installing
1005 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1006 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1007 would be no way to send out the mails, so there is now a host list
1008 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1009 PIPELINING problem as well. Maybe it can also be useful to cure other
1010 problems with broken servers.
1012 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1013 Then somebody tried it with a Microsoft mailer... It seems that all other
1014 mailers use upper case for some reason (the RFC is quite clear about case
1015 independence) so, for peace of mind, I gave in. */
1017 esmtp = verify_check_this_host(&(ob->hosts_avoid_esmtp), NULL,
1018 host->name, host->address, NULL) != OK;
1022 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1023 lmtp? "LHLO" : "EHLO", helo_data) < 0)
1025 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1026 ob->command_timeout))
1028 if (errno != 0 || buffer[0] == 0 || lmtp) goto RESPONSE_FAILED;
1035 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1040 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1042 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1043 ob->command_timeout)) goto RESPONSE_FAILED;
1046 /* Set IGNOREQUOTA if the response to LHLO specifies support and the
1047 lmtp_ignore_quota option was set. */
1049 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1050 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1051 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1053 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1056 tls_offered = esmtp &&
1057 pcre_exec(regex_STARTTLS, NULL, CS buffer, Ustrlen(buffer), 0,
1058 PCRE_EOPT, NULL, 0) >= 0;
1062 /* For continuing deliveries down the same channel, the socket is the standard
1063 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1064 below). Set up the pointer to where subsequent commands will be left, for
1065 error messages. Note that smtp_use_size and smtp_use_pipelining will have been
1066 set from the command line if they were set in the process that passed the
1071 inblock.sock = outblock.sock = fileno(stdin);
1072 smtp_command = big_buffer;
1073 host->port = port; /* Record the port that was used */
1076 /* If TLS is available on this connection, whether continued or not, attempt to
1077 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1078 send another EHLO - the server may give a different answer in secure mode. We
1079 use a separate buffer for reading the response to STARTTLS so that if it is
1080 negative, the original EHLO data is available for subsequent analysis, should
1081 the client not be required to use TLS. If the response is bad, copy the buffer
1082 for error analysis. */
1085 if (tls_offered && !suppress_tls &&
1086 verify_check_this_host(&(ob->hosts_avoid_tls), NULL, host->name,
1087 host->address, NULL) != OK)
1089 uschar buffer2[4096];
1090 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1093 /* If there is an I/O error, transmission of this message is deferred. If
1094 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1095 false, we also defer. However, if there is a temporary rejection of STARTTLS
1096 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1097 STARTTLS, we carry on. This means we will try to send the message in clear,
1098 unless the host is in hosts_require_tls (tested below). */
1100 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1101 ob->command_timeout))
1103 Ustrncpy(buffer, buffer2, sizeof(buffer));
1104 if (errno != 0 || buffer2[0] == 0 ||
1105 (buffer2[0] == '4' && !ob->tls_tempfail_tryclear))
1106 goto RESPONSE_FAILED;
1109 /* STARTTLS accepted: try to negotiate a TLS session. */
1113 int rc = tls_client_start(inblock.sock,
1116 NULL, /* No DH param */
1117 ob->tls_certificate,
1119 ob->tls_verify_certificates,
1121 ob->tls_require_ciphers,
1122 ob->gnutls_require_mac,
1123 ob->gnutls_require_kx,
1124 ob->gnutls_require_proto,
1125 ob->command_timeout);
1127 /* TLS negotiation failed; give an error. From outside, this function may
1128 be called again to try in clear on a new connection, if the options permit
1129 it for this host. */
1133 save_errno = ERRNO_TLSFAILURE;
1134 message = US"failure while setting up TLS session";
1139 /* TLS session is set up */
1141 for (addr = addrlist; addr != NULL; addr = addr->next)
1143 if (addr->transport_return == PENDING_DEFER)
1145 addr->cipher = tls_cipher;
1146 addr->peerdn = tls_peerdn;
1152 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1153 helo_data is null, we are dealing with a connection that was passed from
1154 another process, and so we won't have expanded helo_data above. We have to
1155 expand it here. $sending_ip_address and $sending_port are set up right at the
1156 start of the Exim process (in exim.c). */
1158 if (tls_active >= 0)
1160 if (helo_data == NULL)
1162 helo_data = expand_string(ob->helo_data);
1163 if (helo_data == NULL)
1165 uschar *message = string_sprintf("failed to expand helo_data: %s",
1166 expand_string_message);
1167 set_errno(addrlist, 0, message, DEFER, FALSE);
1173 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n", lmtp? "LHLO" : "EHLO",
1176 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1177 ob->command_timeout))
1178 goto RESPONSE_FAILED;
1181 /* If the host is required to use a secure channel, ensure that we
1184 else if (verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
1185 host->address, NULL) == OK)
1187 save_errno = ERRNO_TLSREQUIRED;
1188 message = string_sprintf("a TLS session is required for %s [%s], but %s",
1189 host->name, host->address,
1190 tls_offered? "an attempt to start TLS failed" :
1191 "the server did not offer TLS support");
1196 /* If TLS is active, we have just started it up and re-done the EHLO command,
1197 so its response needs to be analyzed. If TLS is not active and this is a
1198 continued session down a previously-used socket, we haven't just done EHLO, so
1201 if (continue_hostname == NULL
1208 uschar *fail_reason = US"server did not advertise AUTH support";
1210 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
1211 lmtp_ignore_quota option was set. */
1213 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1214 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1215 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1217 /* If the response to EHLO specified support for the SIZE parameter, note
1218 this, provided size_addition is non-negative. */
1220 smtp_use_size = esmtp && ob->size_addition >= 0 &&
1221 pcre_exec(regex_SIZE, NULL, CS buffer, Ustrlen(CS buffer), 0,
1222 PCRE_EOPT, NULL, 0) >= 0;
1224 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
1225 the current host, esmtp will be false, so PIPELINING can never be used. If
1226 the current host matches hosts_avoid_pipelining, don't do it. */
1228 smtp_use_pipelining = esmtp &&
1229 verify_check_this_host(&(ob->hosts_avoid_pipelining), NULL, host->name,
1230 host->address, NULL) != OK &&
1231 pcre_exec(regex_PIPELINING, NULL, CS buffer, Ustrlen(CS buffer), 0,
1232 PCRE_EOPT, NULL, 0) >= 0;
1234 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
1235 smtp_use_pipelining? "" : "not ");
1237 /* Note if the response to EHLO specifies support for the AUTH extension.
1238 If it has, check that this host is one we want to authenticate to, and do
1239 the business. The host name and address must be available when the
1240 authenticator's client driver is running. */
1242 smtp_authenticated = FALSE;
1243 require_auth = verify_check_this_host(&(ob->hosts_require_auth), NULL,
1244 host->name, host->address, NULL);
1246 if (esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
1248 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
1249 expand_nmax = -1; /* reset */
1251 /* Must not do this check until after we have saved the result of the
1252 regex match above. */
1254 if (require_auth == OK ||
1255 verify_check_this_host(&(ob->hosts_try_auth), NULL, host->name,
1256 host->address, NULL) == OK)
1259 fail_reason = US"no common mechanisms were found";
1261 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1263 /* Scan the configured authenticators looking for one which is configured
1264 for use as a client, which is not suppressed by client_condition, and
1265 whose name matches an authentication mechanism supported by the server.
1266 If one is found, attempt to authenticate by calling its client function.
1269 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1273 (au->client_condition != NULL &&
1274 !expand_check_condition(au->client_condition, au->name,
1275 US"client authenticator")))
1277 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1279 (au->client)? "client_condition is false" :
1280 "not configured as a client");
1284 /* Loop to scan supported server mechanisms */
1289 int len = Ustrlen(au->public_name);
1290 while (isspace(*p)) p++;
1292 if (strncmpic(au->public_name, p, len) != 0 ||
1293 (p[len] != 0 && !isspace(p[len])))
1295 while (*p != 0 && !isspace(*p)) p++;
1299 /* Found data for a listed mechanism. Call its client entry. Set
1300 a flag in the outblock so that data is overwritten after sending so
1301 that reflections don't show it. */
1303 fail_reason = US"authentication attempt(s) failed";
1304 outblock.authenticating = TRUE;
1305 rc = (au->info->clientcode)(au, &inblock, &outblock,
1306 ob->command_timeout, buffer, sizeof(buffer));
1307 outblock.authenticating = FALSE;
1308 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1311 /* A temporary authentication failure must hold up delivery to
1312 this host. After a permanent authentication failure, we carry on
1313 to try other authentication methods. If all fail hard, try to
1314 deliver the message unauthenticated unless require_auth was set. */
1319 smtp_authenticated = TRUE; /* stops the outer loop */
1322 /* Failure after writing a command */
1327 /* Failure after reading a response */
1330 if (errno != 0 || buffer[0] != '5') goto RESPONSE_FAILED;
1331 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1332 au->name, host->name, host->address, buffer);
1335 /* Failure by some other means. In effect, the authenticator
1336 decided it wasn't prepared to handle this case. Typically this
1337 is the result of "fail" in an expansion string. Do we need to
1338 log anything here? Feb 2006: a message is now put in the buffer
1339 if logging is required. */
1343 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1344 "authentication H=%s [%s] %s", au->name, host->name,
1345 host->address, buffer);
1348 /* Internal problem, message in buffer. */
1352 set_errno(addrlist, 0, string_copy(buffer), DEFER, FALSE);
1356 break; /* If not authenticated, try next authenticator */
1357 } /* Loop for scanning supported server mechanisms */
1358 } /* Loop for further authenticators */
1362 /* If we haven't authenticated, but are required to, give up. */
1364 if (require_auth == OK && !smtp_authenticated)
1367 set_errno(addrlist, ERRNO_AUTHFAIL,
1368 string_sprintf("authentication required but %s", fail_reason), DEFER,
1374 /* The setting up of the SMTP call is now complete. Any subsequent errors are
1375 message-specific. */
1379 /* If there is a filter command specified for this transport, we can now
1380 set it up. This cannot be done until the identify of the host is known. */
1382 if (tblock->filter_command != NULL)
1386 sprintf(CS buffer, "%.50s transport", tblock->name);
1387 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
1388 TRUE, DEFER, addrlist, buffer, NULL);
1390 /* On failure, copy the error to all addresses, abandon the SMTP call, and
1395 set_errno(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
1403 /* For messages that have more than the maximum number of envelope recipients,
1404 we want to send several transactions down the same SMTP connection. (See
1405 comments in deliver.c as to how this reconciles, heuristically, with
1406 remote_max_parallel.) This optimization was added to Exim after the following
1407 code was already working. The simplest way to put it in without disturbing the
1408 code was to use a goto to jump back to this point when there is another
1409 transaction to handle. */
1412 sync_addr = first_addr;
1416 completed_address = FALSE;
1419 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
1420 qualification, send it, adding something to the message size to allow for
1421 imprecision and things that get added en route. Exim keeps the number of lines
1422 in a message, so we can give an accurate value for the original message, but we
1423 need some additional to handle added headers. (Double "." characters don't get
1424 included in the count.) */
1431 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
1435 /* Add the authenticated sender address if present */
1437 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1438 local_authenticated_sender != NULL)
1440 string_format(p, sizeof(buffer) - (p-buffer), " AUTH=%s",
1441 auth_xtextencode(local_authenticated_sender,
1442 Ustrlen(local_authenticated_sender)));
1445 /* From here until we send the DATA command, we can make use of PIPELINING
1446 if the server host supports it. The code has to be able to check the responses
1447 at any point, for when the buffer fills up, so we write it totally generally.
1448 When PIPELINING is off, each command written reports that it has flushed the
1451 pending_MAIL = TRUE; /* The block starts with MAIL */
1453 rc = smtp_write_command(&outblock, smtp_use_pipelining,
1454 "MAIL FROM:<%s>%s\r\n", return_path, buffer);
1455 mail_command = string_copy(big_buffer); /* Save for later error message */
1459 case -1: /* Transmission error */
1462 case +1: /* Block was sent */
1463 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1464 ob->command_timeout))
1466 if (errno == 0 && buffer[0] == '4')
1468 errno = ERRNO_MAIL4XX;
1469 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1471 goto RESPONSE_FAILED;
1473 pending_MAIL = FALSE;
1477 /* Pass over all the relevant recipient addresses for this host, which are the
1478 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
1479 several before we have to read the responses for those seen so far. This
1480 checking is done by a subroutine because it also needs to be done at the end.
1481 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
1482 the next one if not all are sent.
1484 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
1485 last address because we want to abort if any recipients have any kind of
1486 problem, temporary or permanent. We know that all recipient addresses will have
1487 the PENDING_DEFER status, because only one attempt is ever made, and we know
1488 that max_rcpt will be large, so all addresses will be done at once. */
1490 for (addr = first_addr;
1491 address_count < max_rcpt && addr != NULL;
1497 if (addr->transport_return != PENDING_DEFER) continue;
1500 no_flush = smtp_use_pipelining && (!mua_wrapper || addr->next != NULL);
1502 /* Now send the RCPT command, and process outstanding responses when
1503 necessary. After a timeout on RCPT, we just end the function, leaving the
1504 yield as OK, because this error can often mean that there is a problem with
1505 just one address, so we don't want to delay the host. */
1507 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s\r\n",
1508 transport_rcpt_address(addr, tblock->rcpt_include_affixes), igquotstr);
1509 if (count < 0) goto SEND_FAILED;
1512 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
1513 &sync_addr, host, count, ob->address_retry_include_sender,
1514 pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
1517 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1518 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1521 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1522 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1523 case 0: /* No 2xx or 5xx, but no probs */
1526 case -1: goto END_OFF; /* Timeout on RCPT */
1527 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
1529 pending_MAIL = FALSE; /* Dealt with MAIL */
1531 } /* Loop for next address */
1533 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
1534 permanently or temporarily. We should have flushed and synced after the last
1539 address_item *badaddr;
1540 for (badaddr = first_addr; badaddr != NULL; badaddr = badaddr->next)
1542 if (badaddr->transport_return != PENDING_OK) break;
1544 if (badaddr != NULL)
1546 set_errno(addrlist, 0, badaddr->message, FAIL,
1547 testflag(badaddr, af_pass_message));
1552 /* If ok is TRUE, we know we have got at least one good recipient, and must now
1553 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
1554 have a good recipient buffered up if we are pipelining. We don't want to waste
1555 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
1556 are pipelining. The responses are all handled by sync_responses(). */
1558 if (ok || (smtp_use_pipelining && !mua_wrapper))
1560 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
1561 if (count < 0) goto SEND_FAILED;
1562 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
1563 host, count, ob->address_retry_include_sender, pending_MAIL,
1564 ok? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
1566 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1567 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1570 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1571 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1572 case 0: break; /* No 2xx or 5xx, but no probs */
1574 case -1: goto END_OFF; /* Timeout on RCPT */
1575 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
1579 /* Save the first address of the next batch. */
1583 /* If there were no good recipients (but otherwise there have been no
1584 problems), just set ok TRUE, since we have handled address-specific errors
1585 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
1586 for handling the SMTP dot-handling protocol, flagging to apply to headers as
1587 well as body. Set the appropriate timeout value to be used for each chunk.
1588 (Haven't been able to make it work using select() for writing yet.) */
1590 if (!ok) ok = TRUE; else
1592 sigalrm_seen = FALSE;
1593 transport_write_timeout = ob->data_timeout;
1594 smtp_command = US"sending data block"; /* For error messages */
1595 DEBUG(D_transport|D_v)
1596 debug_printf(" SMTP>> writing message and terminating \".\"\n");
1597 transport_count = 0;
1598 #ifdef EXPERIMENTAL_DOMAINKEYS
1599 if ( (ob->dk_private_key != NULL) && (ob->dk_selector != NULL) )
1600 ok = dk_transport_write_message(addrlist, inblock.sock,
1601 topt_use_crlf | topt_end_dot | topt_escape_headers |
1602 (tblock->body_only? topt_no_headers : 0) |
1603 (tblock->headers_only? topt_no_body : 0) |
1604 (tblock->return_path_add? topt_add_return_path : 0) |
1605 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1606 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1607 0, /* No size limit */
1608 tblock->add_headers, tblock->remove_headers,
1609 US".", US"..", /* Escaping strings */
1610 tblock->rewrite_rules, tblock->rewrite_existflags,
1611 ob->dk_private_key, ob->dk_domain, ob->dk_selector,
1612 ob->dk_canon, ob->dk_headers, ob->dk_strict);
1615 #ifdef EXPERIMENTAL_DKIM
1616 if ( (ob->dkim_private_key != NULL) && (ob->dkim_domain != NULL) && (ob->dkim_selector != NULL) )
1617 ok = dkim_transport_write_message(addrlist, inblock.sock,
1618 topt_use_crlf | topt_end_dot | topt_escape_headers |
1619 (tblock->body_only? topt_no_headers : 0) |
1620 (tblock->headers_only? topt_no_body : 0) |
1621 (tblock->return_path_add? topt_add_return_path : 0) |
1622 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1623 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1624 0, /* No size limit */
1625 tblock->add_headers, tblock->remove_headers,
1626 US".", US"..", /* Escaping strings */
1627 tblock->rewrite_rules, tblock->rewrite_existflags,
1628 ob->dkim_private_key, ob->dkim_domain, ob->dkim_selector,
1629 ob->dkim_canon, ob->dkim_strict, ob->dkim_sign_headers);
1632 ok = transport_write_message(addrlist, inblock.sock,
1633 topt_use_crlf | topt_end_dot | topt_escape_headers |
1634 (tblock->body_only? topt_no_headers : 0) |
1635 (tblock->headers_only? topt_no_body : 0) |
1636 (tblock->return_path_add? topt_add_return_path : 0) |
1637 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1638 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1639 0, /* No size limit */
1640 tblock->add_headers, tblock->remove_headers,
1641 US".", US"..", /* Escaping strings */
1642 tblock->rewrite_rules, tblock->rewrite_existflags);
1644 /* transport_write_message() uses write() because it is called from other
1645 places to write to non-sockets. This means that under some OS (e.g. Solaris)
1646 it can exit with "Broken pipe" as its error. This really means that the
1647 socket got closed at the far end. */
1649 transport_write_timeout = 0; /* for subsequent transports */
1651 /* Failure can either be some kind of I/O disaster (including timeout),
1652 or the failure of a transport filter or the expansion of added headers. */
1656 buffer[0] = 0; /* There hasn't been a response */
1657 goto RESPONSE_FAILED;
1660 /* We used to send the terminating "." explicitly here, but because of
1661 buffering effects at both ends of TCP/IP connections, you don't gain
1662 anything by keeping it separate, so it might as well go in the final
1663 data buffer for efficiency. This is now done by setting the topt_end_dot
1666 smtp_command = US"end of data";
1668 /* For SMTP, we now read a single response that applies to the whole message.
1669 If it is OK, then all the addresses have been delivered. */
1673 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1675 if (!ok && errno == 0 && buffer[0] == '4')
1677 errno = ERRNO_DATA4XX;
1678 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1682 /* For LMTP, we get back a response for every RCPT command that we sent;
1683 some may be accepted and some rejected. For those that get a response, their
1684 status is fixed; any that are accepted have been handed over, even if later
1685 responses crash - at least, that's how I read RFC 2033.
1687 If all went well, mark the recipient addresses as completed, record which
1688 host/IPaddress they were delivered to, and cut out RSET when sending another
1689 message down the same channel. Write the completed addresses to the journal
1690 now so that they are recorded in case there is a crash of hardware or
1691 software before the spool gets updated. Also record the final SMTP
1692 confirmation if needed (for SMTP only). */
1697 int delivery_time = (int)(time(NULL) - start_delivery_time);
1700 uschar *conf = NULL;
1703 /* Make a copy of the host if it is local to this invocation
1704 of the transport. */
1708 thost = store_get(sizeof(host_item));
1710 thost->name = string_copy(host->name);
1711 thost->address = string_copy(host->address);
1715 /* Set up confirmation if needed - applies only to SMTP */
1717 if ((log_extra_selector & LX_smtp_confirmation) != 0 && !lmtp)
1719 uschar *s = string_printing(buffer);
1720 conf = (s == buffer)? (uschar *)string_copy(s) : s;
1723 /* Process all transported addresses - for LMTP, read a status for
1726 for (addr = addrlist; addr != first_addr; addr = addr->next)
1728 if (addr->transport_return != PENDING_OK) continue;
1730 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
1731 remaining addresses. Otherwise, it's a return code for just the one
1732 address. For temporary errors, add a retry item for the address so that
1733 it doesn't get tried again too soon. */
1737 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1740 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
1741 addr->message = string_sprintf("LMTP error after %s: %s",
1742 big_buffer, string_printing(buffer));
1743 setflag(addr, af_pass_message); /* Allow message to go to user */
1744 if (buffer[0] == '5')
1745 addr->transport_return = FAIL;
1748 errno = ERRNO_DATA4XX;
1749 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1750 addr->transport_return = DEFER;
1751 retry_add_item(addr, addr->address_retry_key, 0);
1755 completed_address = TRUE; /* NOW we can set this flag */
1758 /* SMTP, or success return from LMTP for this address. Pass back the
1759 actual host that was used. */
1761 addr->transport_return = OK;
1762 addr->more_errno = delivery_time;
1763 addr->host_used = thost;
1764 addr->special_action = flag;
1765 addr->message = conf;
1768 /* Update the journal. For homonymic addresses, use the base address plus
1769 the transport name. See lots of comments in deliver.c about the reasons
1770 for the complications when homonyms are involved. Just carry on after
1771 write error, as it may prove possible to update the spool file later. */
1773 if (testflag(addr, af_homonym))
1774 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
1776 sprintf(CS buffer, "%.500s\n", addr->unique);
1778 DEBUG(D_deliver) debug_printf("journalling %s", buffer);
1779 len = Ustrlen(CS buffer);
1780 if (write(journal_fd, buffer, len) != len)
1781 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
1782 "%s: %s", buffer, strerror(errno));
1785 /* Ensure the journal file is pushed out to disk. */
1787 if (EXIMfsync(journal_fd) < 0)
1788 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
1794 /* Handle general (not specific to one address) failures here. The value of ok
1795 is used to skip over this code on the falling through case. A timeout causes a
1796 deferral. Other errors may defer or fail according to the response code, and
1797 may set up a special errno value, e.g. after connection chopped, which is
1798 assumed if errno == 0 and there is no text in the buffer. If control reaches
1799 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
1800 the problem is not related to this specific message. */
1809 send_quit = check_response(host, &save_errno, addrlist->more_errno,
1810 buffer, &code, &message, &pass_message);
1816 message = US string_sprintf("send() to %s [%s] failed: %s",
1817 host->name, host->address, strerror(save_errno));
1821 /* This label is jumped to directly when a TLS negotiation has failed,
1822 or was not done for a host for which it is required. Values will be set
1823 in message and save_errno, and setting_up will always be true. Treat as
1824 a temporary error. */
1831 /* If the failure happened while setting up the call, see if the failure was
1832 a 5xx response (this will either be on connection, or following HELO - a 5xx
1833 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
1834 never going to accept them. For other errors during setting up (timeouts or
1835 whatever), defer all addresses, and yield DEFER, so that the host is not
1836 tried again for a while. */
1839 ok = FALSE; /* For when reached by GOTO */
1845 set_errno(addrlist, save_errno, message, FAIL, pass_message);
1849 set_errno(addrlist, save_errno, message, DEFER, pass_message);
1854 /* We want to handle timeouts after MAIL or "." and loss of connection after
1855 "." specially. They can indicate a problem with the sender address or with
1856 the contents of the message rather than a real error on the connection. These
1857 cases are treated in the same way as a 4xx response. This next bit of code
1858 does the classification. */
1869 message_error = TRUE;
1873 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
1874 Ustrncmp(smtp_command,"end ",4) == 0;
1877 case ERRNO_SMTPCLOSED:
1878 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
1882 message_error = FALSE;
1886 /* Handle the cases that are treated as message errors. These are:
1888 (a) negative response or timeout after MAIL
1889 (b) negative response after DATA
1890 (c) negative response or timeout or dropped connection after "."
1892 It won't be a negative response or timeout after RCPT, as that is dealt
1893 with separately above. The action in all cases is to set an appropriate
1894 error code for all the addresses, but to leave yield set to OK because the
1895 host itself has not failed. Of course, it might in practice have failed
1896 when we've had a timeout, but if so, we'll discover that at the next
1897 delivery attempt. For a temporary error, set the message_defer flag, and
1898 write to the logs for information if this is not the last host. The error
1899 for the last host will be logged as part of the address's log line. */
1903 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
1904 set_errno(addrlist, save_errno, message, (code == '5')? FAIL : DEFER,
1907 /* If there's an errno, the message contains just the identity of
1910 if (code != '5') /* Anything other than 5 is treated as temporary */
1913 message = US string_sprintf("%s: %s", message, strerror(save_errno));
1914 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
1915 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
1916 *message_defer = TRUE;
1920 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
1921 ".", or some other transportation error. We defer all addresses and yield
1922 DEFER, except for the case of failed add_headers expansion, or a transport
1923 filter failure, when the yield should be ERROR, to stop it trying other
1928 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
1929 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
1930 set_errno(addrlist, save_errno, message, DEFER, pass_message);
1936 /* If all has gone well, send_quit will be set TRUE, implying we can end the
1937 SMTP session tidily. However, if there were too many addresses to send in one
1938 message (indicated by first_addr being non-NULL) we want to carry on with the
1939 rest of them. Also, it is desirable to send more than one message down the SMTP
1940 connection if there are several waiting, provided we haven't already sent so
1941 many as to hit the configured limit. The function transport_check_waiting looks
1942 for a waiting message and returns its id. Then transport_pass_socket tries to
1943 set up a continued delivery by passing the socket on to another process. The
1944 variable send_rset is FALSE if a message has just been successfully transfered.
1946 If we are already sending down a continued channel, there may be further
1947 addresses not yet delivered that are aimed at the same host, but which have not
1948 been passed in this run of the transport. In this case, continue_more will be
1949 true, and all we should do is send RSET if necessary, and return, leaving the
1952 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
1953 do not want to continue with other messages down the same channel, because that
1954 can lead to looping between two or more messages, all with the same,
1955 temporarily failing address(es). [The retry information isn't updated yet, so
1956 new processes keep on trying.] We probably also don't want to try more of this
1957 message's addresses either.
1959 If we have started a TLS session, we have to end it before passing the
1960 connection to a new process. However, not all servers can handle this (Exim
1961 can), so we do not pass such a connection on if the host matches
1962 hosts_nopass_tls. */
1965 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
1966 "yield=%d first_address is %sNULL\n", ok, send_quit, send_rset,
1967 continue_more, yield, (first_addr == NULL)? "":"not ");
1969 if (completed_address && ok && send_quit)
1972 if (first_addr != NULL || continue_more ||
1975 verify_check_this_host(&(ob->hosts_nopass_tls), NULL, host->name,
1976 host->address, NULL) != OK)
1978 transport_check_waiting(tblock->name, host->name,
1979 tblock->connection_max_messages, new_message_id, &more)
1987 if (! (ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
1989 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
1990 host->address, strerror(save_errno));
1993 else if (! (ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1994 ob->command_timeout)))
1997 send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
2001 DEBUG(D_transport) debug_printf("%s\n", msg);
2006 /* Either RSET was not needed, or it succeeded */
2010 if (first_addr != NULL) /* More addresses still to be sent */
2011 { /* in this run of the transport */
2012 continue_sequence++; /* Causes * in logging */
2015 if (continue_more) return yield; /* More addresses for another run */
2017 /* Pass the socket to a new Exim process. Before doing so, we must shut
2018 down TLS. Not all MTAs allow for the continuation of the SMTP session
2019 when TLS is shut down. We test for this by sending a new EHLO. If we
2020 don't get a good response, we don't attempt to pass the socket on. */
2023 if (tls_active >= 0)
2026 ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
2027 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2028 ob->command_timeout);
2032 /* If the socket is successfully passed, we musn't send QUIT (or
2033 indeed anything!) from here. */
2035 if (ok && transport_pass_socket(tblock->name, host->name, host->address,
2036 new_message_id, inblock.sock))
2042 /* If RSET failed and there are addresses left, they get deferred. */
2044 else set_errno(first_addr, errno, msg, DEFER, FALSE);
2048 /* End off tidily with QUIT unless the connection has died or the socket has
2049 been passed to another process. There has been discussion on the net about what
2050 to do after sending QUIT. The wording of the RFC suggests that it is necessary
2051 to wait for a response, but on the other hand, there isn't anything one can do
2052 with an error response, other than log it. Exim used to do that. However,
2053 further discussion suggested that it is positively advantageous not to wait for
2054 the response, but to close the session immediately. This is supposed to move
2055 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
2056 load from the server. (Hosts that are both servers and clients may not see much
2057 difference, of course.) Further discussion indicated that this was safe to do
2058 on Unix systems which have decent implementations of TCP/IP that leave the
2059 connection around for a while (TIME_WAIT) after the application has gone away.
2060 This enables the response sent by the server to be properly ACKed rather than
2061 timed out, as can happen on broken TCP/IP implementations on other OS.
2063 This change is being made on 31-Jul-98. After over a year of trouble-free
2064 operation, the old commented-out code was removed on 17-Sep-99. */
2067 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2075 /* Close the socket, and return the appropriate value, first setting
2076 continue_transport and continue_hostname NULL to prevent any other addresses
2077 that may include the host from trying to re-use a continuation socket. This
2078 works because the NULL setting is passed back to the calling process, and
2079 remote_max_parallel is forced to 1 when delivering over an existing connection,
2081 If all went well and continue_more is set, we shouldn't actually get here if
2082 there are further addresses, as the return above will be taken. However,
2083 writing RSET might have failed, or there may be other addresses whose hosts are
2084 specified in the transports, and therefore not visible at top level, in which
2085 case continue_more won't get set. */
2087 (void)close(inblock.sock);
2088 continue_transport = NULL;
2089 continue_hostname = NULL;
2096 /*************************************************
2097 * Closedown entry point *
2098 *************************************************/
2100 /* This function is called when exim is passed an open smtp channel
2101 from another incarnation, but the message which it has been asked
2102 to deliver no longer exists. The channel is on stdin.
2104 We might do fancy things like looking for another message to send down
2105 the channel, but if the one we sought has gone, it has probably been
2106 delivered by some other process that itself will seek further messages,
2107 so just close down our connection.
2109 Argument: pointer to the transport instance block
2114 smtp_transport_closedown(transport_instance *tblock)
2116 smtp_transport_options_block *ob =
2117 (smtp_transport_options_block *)(tblock->options_block);
2118 smtp_inblock inblock;
2119 smtp_outblock outblock;
2121 uschar inbuffer[4096];
2122 uschar outbuffer[16];
2124 inblock.sock = fileno(stdin);
2125 inblock.buffer = inbuffer;
2126 inblock.buffersize = sizeof(inbuffer);
2127 inblock.ptr = inbuffer;
2128 inblock.ptrend = inbuffer;
2130 outblock.sock = inblock.sock;
2131 outblock.buffersize = sizeof(outbuffer);
2132 outblock.buffer = outbuffer;
2133 outblock.ptr = outbuffer;
2134 outblock.cmd_count = 0;
2135 outblock.authenticating = FALSE;
2137 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2138 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2139 ob->command_timeout);
2140 (void)close(inblock.sock);
2145 /*************************************************
2146 * Prepare addresses for delivery *
2147 *************************************************/
2149 /* This function is called to flush out error settings from previous delivery
2150 attempts to other hosts. It also records whether we got here via an MX record
2151 or not in the more_errno field of the address. We are interested only in
2152 addresses that are still marked DEFER - others may have got delivered to a
2153 previously considered IP address. Set their status to PENDING_DEFER to indicate
2154 which ones are relevant this time.
2157 addrlist the list of addresses
2158 host the host we are delivering to
2160 Returns: the first address for this delivery
2163 static address_item *
2164 prepare_addresses(address_item *addrlist, host_item *host)
2166 address_item *first_addr = NULL;
2168 for (addr = addrlist; addr != NULL; addr = addr->next)
2170 if (addr->transport_return != DEFER) continue;
2171 if (first_addr == NULL) first_addr = addr;
2172 addr->transport_return = PENDING_DEFER;
2173 addr->basic_errno = 0;
2174 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
2175 addr->message = NULL;
2177 addr->cipher = NULL;
2178 addr->peerdn = NULL;
2186 /*************************************************
2187 * Main entry point *
2188 *************************************************/
2190 /* See local README for interface details. As this is a remote transport, it is
2191 given a chain of addresses to be delivered in one connection, if possible. It
2192 always returns TRUE, indicating that each address has its own independent
2193 status set, except if there is a setting up problem, in which case it returns
2197 smtp_transport_entry(
2198 transport_instance *tblock, /* data for this instantiation */
2199 address_item *addrlist) /* addresses we are working on */
2203 int hosts_defer = 0;
2205 int hosts_looked_up = 0;
2206 int hosts_retry = 0;
2207 int hosts_serial = 0;
2208 int hosts_total = 0;
2209 int total_hosts_tried = 0;
2211 BOOL expired = TRUE;
2212 BOOL continuing = continue_hostname != NULL;
2213 uschar *expanded_hosts = NULL;
2215 uschar *tid = string_sprintf("%s transport", tblock->name);
2216 smtp_transport_options_block *ob =
2217 (smtp_transport_options_block *)(tblock->options_block);
2218 host_item *hostlist = addrlist->host_list;
2219 host_item *host = NULL;
2223 debug_printf("%s transport entered\n", tblock->name);
2224 for (addr = addrlist; addr != NULL; addr = addr->next)
2225 debug_printf(" %s\n", addr->address);
2226 if (continuing) debug_printf("already connected to %s [%s]\n",
2227 continue_hostname, continue_host_address);
2230 /* Set the flag requesting that these hosts be added to the waiting
2231 database if the delivery fails temporarily or if we are running with
2232 queue_smtp or a 2-stage queue run. This gets unset for certain
2233 kinds of error, typically those that are specific to the message. */
2235 update_waiting = TRUE;
2237 /* If a host list is not defined for the addresses - they must all have the
2238 same one in order to be passed to a single transport - or if the transport has
2239 a host list with hosts_override set, use the host list supplied with the
2240 transport. It is an error for this not to exist. */
2242 if (hostlist == NULL || (ob->hosts_override && ob->hosts != NULL))
2244 if (ob->hosts == NULL)
2246 addrlist->message = string_sprintf("%s transport called with no hosts set",
2248 addrlist->transport_return = PANIC;
2249 return FALSE; /* Only top address has status */
2252 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
2255 /* If the transport's host list contains no '$' characters, and we are not
2256 randomizing, it is fixed and therefore a chain of hosts can be built once
2257 and for all, and remembered for subsequent use by other calls to this
2258 transport. If, on the other hand, the host list does contain '$', or we are
2259 randomizing its order, we have to rebuild it each time. In the fixed case,
2260 as the hosts string will never be used again, it doesn't matter that we
2261 replace all the : characters with zeros. */
2263 if (ob->hostlist == NULL)
2265 uschar *s = ob->hosts;
2267 if (Ustrchr(s, '$') != NULL)
2269 expanded_hosts = expand_string(s);
2270 if (expanded_hosts == NULL)
2272 addrlist->message = string_sprintf("failed to expand list of hosts "
2273 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
2274 addrlist->transport_return = search_find_defer? DEFER : PANIC;
2275 return FALSE; /* Only top address has status */
2277 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
2278 "\"%s\"\n", s, expanded_hosts);
2282 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
2284 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
2286 /* If there was no expansion of hosts, save the host list for
2289 if (expanded_hosts == NULL) ob->hostlist = hostlist;
2292 /* This is not the first time this transport has been run in this delivery;
2293 the host list was built previously. */
2295 else hostlist = ob->hostlist;
2298 /* The host list was supplied with the address. If hosts_randomize is set, we
2299 must sort it into a random order if it did not come from MX records and has not
2300 already been randomized (but don't bother if continuing down an existing
2303 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continuing)
2305 host_item *newlist = NULL;
2306 while (hostlist != NULL)
2308 host_item *h = hostlist;
2309 hostlist = hostlist->next;
2311 h->sort_key = random_number(100);
2313 if (newlist == NULL)
2318 else if (h->sort_key < newlist->sort_key)
2325 host_item *hh = newlist;
2326 while (hh->next != NULL)
2328 if (h->sort_key < hh->next->sort_key) break;
2336 hostlist = addrlist->host_list = newlist;
2340 /* Sort out the default port. */
2342 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
2345 /* For each host-plus-IP-address on the list:
2347 . If this is a continued delivery and the host isn't the one with the
2348 current connection, skip.
2350 . If the status is unusable (i.e. previously failed or retry checked), skip.
2352 . If no IP address set, get the address, either by turning the name into
2353 an address, calling gethostbyname if gethostbyname is on, or by calling
2354 the DNS. The DNS may yield multiple addresses, in which case insert the
2355 extra ones into the list.
2357 . Get the retry data if not previously obtained for this address and set the
2358 field which remembers the state of this address. Skip if the retry time is
2359 not reached. If not, remember whether retry data was found. The retry string
2360 contains both the name and the IP address.
2362 . Scan the list of addresses and mark those whose status is DEFER as
2363 PENDING_DEFER. These are the only ones that will be processed in this cycle
2366 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
2367 Some addresses may be successfully delivered, others may fail, and yet
2368 others may get temporary errors and so get marked DEFER.
2370 . The return from the delivery attempt is OK if a connection was made and a
2371 valid SMTP dialogue was completed. Otherwise it is DEFER.
2373 . If OK, add a "remove" retry item for this host/IPaddress, if any.
2375 . If fail to connect, or other defer state, add a retry item.
2377 . If there are any addresses whose status is still DEFER, carry on to the
2378 next host/IPaddress, unless we have tried the number of hosts given
2379 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
2380 there is some fancy logic for hosts_max_try that means its limit can be
2381 overstepped in some circumstances.
2383 If we get to the end of the list, all hosts have deferred at least one address,
2384 or not reached their retry times. If delay_after_cutoff is unset, it requests a
2385 delivery attempt to those hosts whose last try was before the arrival time of
2386 the current message. To cope with this, we have to go round the loop a second
2387 time. After that, set the status and error data for any addresses that haven't
2388 had it set already. */
2390 for (cutoff_retry = 0; expired &&
2391 cutoff_retry < ((ob->delay_after_cutoff)? 1 : 2);
2394 host_item *nexthost = NULL;
2395 int unexpired_hosts_tried = 0;
2397 for (host = hostlist;
2399 unexpired_hosts_tried < ob->hosts_max_try &&
2400 total_hosts_tried < ob->hosts_max_try_hardlimit;
2406 BOOL serialized = FALSE;
2407 BOOL host_is_expired = FALSE;
2408 BOOL message_defer = FALSE;
2409 BOOL ifchanges = FALSE;
2410 BOOL some_deferred = FALSE;
2411 address_item *first_addr = NULL;
2412 uschar *interface = NULL;
2413 uschar *retry_host_key = NULL;
2414 uschar *retry_message_key = NULL;
2415 uschar *serialize_key = NULL;
2417 /* Default next host is next host. :-) But this can vary if the
2418 hosts_max_try limit is hit (see below). It may also be reset if a host
2419 address is looked up here (in case the host was multihomed). */
2421 nexthost = host->next;
2423 /* If the address hasn't yet been obtained from the host name, look it up
2424 now, unless the host is already marked as unusable. If it is marked as
2425 unusable, it means that the router was unable to find its IP address (in
2426 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
2427 the lookup failed last time. We don't get this far if *all* MX records
2428 point to non-existent hosts; that is treated as a hard error.
2430 We can just skip this host entirely. When the hosts came from the router,
2431 the address will timeout based on the other host(s); when the address is
2432 looked up below, there is an explicit retry record added.
2434 Note that we mustn't skip unusable hosts if the address is not unset; they
2435 may be needed as expired hosts on the 2nd time round the cutoff loop. */
2437 if (host->address == NULL)
2439 int new_port, flags;
2441 uschar *canonical_name;
2443 if (host->status >= hstatus_unusable)
2445 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
2450 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
2452 /* The host name is permitted to have an attached port. Find it, and
2453 strip it from the name. Just remember it for now. */
2455 new_port = host_item_get_port(host);
2457 /* Count hosts looked up */
2461 /* Find by name if so configured, or if it's an IP address. We don't
2462 just copy the IP address, because we need the test-for-local to happen. */
2464 flags = HOST_FIND_BY_A;
2465 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
2466 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
2468 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
2469 rc = host_find_byname(host, NULL, flags, &canonical_name, TRUE);
2471 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
2472 &canonical_name, NULL);
2474 /* Update the host (and any additional blocks, resulting from
2475 multihoming) with a host-specific port, if any. */
2477 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
2479 /* Failure to find the host at this time (usually DNS temporary failure)
2480 is really a kind of routing failure rather than a transport failure.
2481 Therefore we add a retry item of the routing kind, not to stop us trying
2482 to look this name up here again, but to ensure the address gets timed
2483 out if the failures go on long enough. A complete failure at this point
2484 commonly points to a configuration error, but the best action is still
2485 to carry on for the next host. */
2487 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
2489 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
2491 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
2492 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
2493 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
2494 host->status = hstatus_unusable;
2496 for (addr = addrlist; addr != NULL; addr = addr->next)
2498 if (addr->transport_return != DEFER) continue;
2499 addr->basic_errno = ERRNO_UNKNOWNHOST;
2501 string_sprintf("failed to lookup IP address for %s", host->name);
2506 /* If the host is actually the local host, we may have a problem, or
2507 there may be some cunning configuration going on. In the problem case,
2508 log things and give up. The default transport status is already DEFER. */
2510 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
2512 for (addr = addrlist; addr != NULL; addr = addr->next)
2514 addr->basic_errno = 0;
2515 addr->message = string_sprintf("%s transport found host %s to be "
2516 "local", tblock->name, host->name);
2520 } /* End of block for IP address lookup */
2522 /* If this is a continued delivery, we are interested only in the host
2523 which matches the name of the existing open channel. The check is put
2524 here after the local host lookup, in case the name gets expanded as a
2525 result of the lookup. Set expired FALSE, to save the outer loop executing
2528 if (continuing && (Ustrcmp(continue_hostname, host->name) != 0 ||
2529 Ustrcmp(continue_host_address, host->address) != 0))
2532 continue; /* With next host */
2535 /* Reset the default next host in case a multihomed host whose addresses
2536 are not looked up till just above added to the host list. */
2538 nexthost = host->next;
2540 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
2541 domain is in queue_smtp_domains, we don't actually want to attempt any
2542 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
2543 there is a lookup defer in queue_smtp_domains, proceed as if the domain
2544 were not in it. We don't want to hold up all SMTP deliveries! Except when
2545 doing a two-stage queue run, don't do this if forcing. */
2547 if ((!deliver_force || queue_2stage) && (queue_smtp ||
2548 match_isinlist(addrlist->domain, &queue_smtp_domains, 0,
2549 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
2552 for (addr = addrlist; addr != NULL; addr = addr->next)
2554 if (addr->transport_return != DEFER) continue;
2555 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
2557 continue; /* With next host */
2560 /* Count hosts being considered - purely for an intelligent comment
2561 if none are usable. */
2565 /* Set $host and $host address now in case they are needed for the
2566 interface expansion or the serialize_hosts check; they remain set if an
2567 actual delivery happens. */
2569 deliver_host = host->name;
2570 deliver_host_address = host->address;
2572 /* Set up a string for adding to the retry key if the port number is not
2573 the standard SMTP port. A host may have its own port setting that overrides
2576 pistring = string_sprintf(":%d", (host->port == PORT_NONE)?
2578 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
2580 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
2581 string changes upon expansion, we must add it to the key that is used for
2582 retries, because connections to the same host from a different interface
2583 should be treated separately. */
2585 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET : AF_INET6;
2586 if (!smtp_get_interface(ob->interface, host_af, addrlist, &ifchanges,
2589 if (ifchanges) pistring = string_sprintf("%s/%s", pistring, interface);
2591 /* The first time round the outer loop, check the status of the host by
2592 inspecting the retry data. The second time round, we are interested only
2593 in expired hosts that haven't been tried since this message arrived. */
2595 if (cutoff_retry == 0)
2597 /* Ensure the status of the address is set by checking retry data if
2598 necessary. There maybe host-specific retry data (applicable to all
2599 messages) and also data for retries of a specific message at this host.
2600 If either of these retry records are actually read, the keys used are
2601 returned to save recomputing them later. */
2603 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
2604 ob->retry_include_ip_address, &retry_host_key, &retry_message_key);
2606 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
2607 (host->address == NULL)? US"" : host->address, pistring,
2608 (host->status == hstatus_usable)? "usable" :
2609 (host->status == hstatus_unusable)? "unusable" :
2610 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
2612 /* Skip this address if not usable at this time, noting if it wasn't
2613 actually expired, both locally and in the address. */
2615 switch (host->status)
2617 case hstatus_unusable:
2619 setflag(addrlist, af_retry_skipped);
2622 case hstatus_unusable_expired:
2625 case hwhy_retry: hosts_retry++; break;
2626 case hwhy_failed: hosts_fail++; break;
2627 case hwhy_deferred: hosts_defer++; break;
2630 /* If there was a retry message key, implying that previously there
2631 was a message-specific defer, we don't want to update the list of
2632 messages waiting for these hosts. */
2634 if (retry_message_key != NULL) update_waiting = FALSE;
2635 continue; /* With the next host or IP address */
2639 /* Second time round the loop: if the address is set but expired, and
2640 the message is newer than the last try, let it through. */
2644 if (host->address == NULL ||
2645 host->status != hstatus_unusable_expired ||
2646 host->last_try > received_time)
2649 debug_printf("trying expired host %s [%s]%s\n",
2650 host->name, host->address, pistring);
2651 host_is_expired = TRUE;
2654 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
2655 it remains TRUE only if all hosts are expired and none are actually tried.
2660 /* If this host is listed as one to which access must be serialized,
2661 see if another Exim process has a connection to it, and if so, skip
2662 this host. If not, update the database to record our connection to it
2663 and remember this for later deletion. Do not do any of this if we are
2664 sending the message down a pre-existing connection. */
2667 verify_check_this_host(&(ob->serialize_hosts), NULL, host->name,
2668 host->address, NULL) == OK)
2670 serialize_key = string_sprintf("host-serialize-%s", host->name);
2671 if (!enq_start(serialize_key))
2674 debug_printf("skipping host %s because another Exim process "
2675 "is connected to it\n", host->name);
2682 /* OK, we have an IP address that is not waiting for its retry time to
2683 arrive (it might be expired) OR (second time round the loop) we have an
2684 expired host that hasn't been tried since the message arrived. Have a go
2685 at delivering the message to it. First prepare the addresses by flushing
2686 out the result of previous attempts, and finding the first address that
2687 is still to be delivered. */
2689 first_addr = prepare_addresses(addrlist, host);
2691 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
2692 message_id, host->name, host->address, addrlist->address,
2693 (addrlist->next == NULL)? "" : ", ...");
2695 set_process_info("delivering %s to %s [%s] (%s%s)",
2696 message_id, host->name, host->address, addrlist->address,
2697 (addrlist->next == NULL)? "" : ", ...");
2699 /* This is not for real; don't do the delivery. If there are
2700 any remaining hosts, list them. */
2705 set_errno(addrlist, 0, NULL, OK, FALSE);
2706 for (addr = addrlist; addr != NULL; addr = addr->next)
2708 addr->host_used = host;
2709 addr->special_action = '*';
2710 addr->message = US"delivery bypassed by -N option";
2714 debug_printf("*** delivery by %s transport bypassed by -N option\n"
2715 "*** host and remaining hosts:\n", tblock->name);
2716 for (host2 = host; host2 != NULL; host2 = host2->next)
2717 debug_printf(" %s [%s]\n", host2->name,
2718 (host2->address == NULL)? US"unset" : host2->address);
2723 /* This is for real. If the host is expired, we don't count it for
2724 hosts_max_retry. This ensures that all hosts must expire before an address
2725 is timed out, unless hosts_max_try_hardlimit (which protects against
2726 lunatic DNS configurations) is reached.
2728 If the host is not expired and we are about to hit the hosts_max_retry
2729 limit, check to see if there is a subsequent hosts with a different MX
2730 value. If so, make that the next host, and don't count this one. This is a
2731 heuristic to make sure that different MXs do get tried. With a normal kind
2732 of retry rule, they would get tried anyway when the earlier hosts were
2733 delayed, but if the domain has a "retry every time" type of rule - as is
2734 often used for the the very large ISPs, that won't happen. */
2738 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
2742 debug_printf("hosts_max_try limit reached with this host\n");
2743 for (h = host; h != NULL; h = h->next)
2744 if (h->mx != host->mx) break;
2748 unexpired_hosts_tried--;
2749 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
2750 "and will be tried\n");
2754 /* Attempt the delivery. */
2756 total_hosts_tried++;
2757 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
2758 expanded_hosts != NULL, &message_defer, FALSE);
2761 OK => connection made, each address contains its result;
2762 message_defer is set for message-specific defers (when all
2763 recipients are marked defer)
2764 DEFER => there was a non-message-specific delivery problem;
2765 ERROR => there was a problem setting up the arguments for a filter,
2766 or there was a problem with expanding added headers
2769 /* If the result is not OK, there was a non-message-specific problem.
2770 If the result is DEFER, we need to write to the logs saying what happened
2771 for this particular host, except in the case of authentication and TLS
2772 failures, where the log has already been written. If all hosts defer a
2773 general message is written at the end. */
2775 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL &&
2776 first_addr->basic_errno != ERRNO_TLSFAILURE)
2777 write_logs(first_addr, host);
2779 /* If STARTTLS was accepted, but there was a failure in setting up the
2780 TLS session (usually a certificate screwup), and the host is not in
2781 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
2782 TLS forcibly turned off. We have to start from scratch with a new SMTP
2783 connection. That's why the retry is done from here, not from within
2784 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
2785 session, so the in-clear transmission after those errors, if permitted,
2786 happens inside smtp_deliver().] */
2789 if (rc == DEFER && first_addr->basic_errno == ERRNO_TLSFAILURE &&
2790 ob->tls_tempfail_tryclear &&
2791 verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
2792 host->address, NULL) != OK)
2794 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
2795 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
2796 first_addr = prepare_addresses(addrlist, host);
2797 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
2798 expanded_hosts != NULL, &message_defer, TRUE);
2799 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
2800 write_logs(first_addr, host);
2805 /* Delivery attempt finished */
2807 rs = (rc == OK)? US"OK" : (rc == DEFER)? US"DEFER" : (rc == ERROR)?
2810 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
2811 message_id, host->name, host->address, addrlist->address,
2812 (addrlist->next == NULL)? "" : " (& others)", rs);
2814 /* Release serialization if set up */
2816 if (serialized) enq_end(serialize_key);
2818 /* If the result is DEFER, or if a host retry record is known to exist, we
2819 need to add an item to the retry chain for updating the retry database
2820 at the end of delivery. We only need to add the item to the top address,
2821 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
2822 for any other delivery attempts using the same address. (It is copied into
2823 the unusable tree at the outer level, so even if different address blocks
2824 contain the same address, it still won't get tried again.) */
2826 if (rc == DEFER || retry_host_key != NULL)
2828 int delete_flag = (rc != DEFER)? rf_delete : 0;
2829 if (retry_host_key == NULL)
2831 retry_host_key = ob->retry_include_ip_address?
2832 string_sprintf("T:%S:%s%s", host->name, host->address, pistring) :
2833 string_sprintf("T:%S%s", host->name, pistring);
2836 /* If a delivery of another message over an existing SMTP connection
2837 yields DEFER, we do NOT set up retry data for the host. This covers the
2838 case when there are delays in routing the addresses in the second message
2839 that are so long that the server times out. This is alleviated by not
2840 routing addresses that previously had routing defers when handling an
2841 existing connection, but even so, this case may occur (e.g. if a
2842 previously happily routed address starts giving routing defers). If the
2843 host is genuinely down, another non-continued message delivery will
2844 notice it soon enough. */
2846 if (delete_flag != 0 || !continuing)
2847 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
2849 /* We may have tried an expired host, if its retry time has come; ensure
2850 the status reflects the expiry for the benefit of any other addresses. */
2854 host->status = (host_is_expired)?
2855 hstatus_unusable_expired : hstatus_unusable;
2856 host->why = hwhy_deferred;
2860 /* If message_defer is set (host was OK, but every recipient got deferred
2861 because of some message-specific problem), or if that had happened
2862 previously so that a message retry key exists, add an appropriate item
2863 to the retry chain. Note that if there was a message defer but now there is
2864 a host defer, the message defer record gets deleted. That seems perfectly
2865 reasonable. Also, stop the message from being remembered as waiting
2866 for specific hosts. */
2868 if (message_defer || retry_message_key != NULL)
2870 int delete_flag = message_defer? 0 : rf_delete;
2871 if (retry_message_key == NULL)
2873 retry_message_key = ob->retry_include_ip_address?
2874 string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
2876 string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
2878 retry_add_item(addrlist, retry_message_key,
2879 rf_message | rf_host | delete_flag);
2880 update_waiting = FALSE;
2883 /* Any return other than DEFER (that is, OK or ERROR) means that the
2884 addresses have got their final statuses filled in for this host. In the OK
2885 case, see if any of them are deferred. */
2889 for (addr = addrlist; addr != NULL; addr = addr->next)
2891 if (addr->transport_return == DEFER)
2893 some_deferred = TRUE;
2899 /* If no addresses deferred or the result was ERROR, return. We do this for
2900 ERROR because a failing filter set-up or add_headers expansion is likely to
2901 fail for any host we try. */
2903 if (rc == ERROR || (rc == OK && !some_deferred))
2905 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
2906 return TRUE; /* Each address has its status */
2909 /* If the result was DEFER or some individual addresses deferred, let
2910 the loop run to try other hosts with the deferred addresses, except for the
2911 case when we were trying to deliver down an existing channel and failed.
2912 Don't try any other hosts in this case. */
2914 if (continuing) break;
2916 /* If the whole delivery, or some individual addresses, were deferred and
2917 there are more hosts that could be tried, do not count this host towards
2918 the hosts_max_try limit if the age of the message is greater than the
2919 maximum retry time for this host. This means we may try try all hosts,
2920 ignoring the limit, when messages have been around for some time. This is
2921 important because if we don't try all hosts, the address will never time
2922 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
2924 if ((rc == DEFER || some_deferred) && nexthost != NULL)
2927 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
2929 if (retry != NULL && retry->rules != NULL)
2931 retry_rule *last_rule;
2932 for (last_rule = retry->rules;
2933 last_rule->next != NULL;
2934 last_rule = last_rule->next);
2935 timedout = time(NULL) - received_time > last_rule->timeout;
2937 else timedout = TRUE; /* No rule => timed out */
2941 unexpired_hosts_tried--;
2942 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
2943 "hosts_max_try (message older than host's retry time)\n");
2946 } /* End of loop for trying multiple hosts. */
2948 /* This is the end of the loop that repeats iff expired is TRUE and
2949 ob->delay_after_cutoff is FALSE. The second time round we will
2950 try those hosts that haven't been tried since the message arrived. */
2954 debug_printf("all IP addresses skipped or deferred at least one address\n");
2955 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
2956 debug_printf("retrying IP addresses not tried since message arrived\n");
2961 /* Get here if all IP addresses are skipped or defer at least one address. In
2962 MUA wrapper mode, this will happen only for connection or other non-message-
2963 specific failures. Force the delivery status for all addresses to FAIL. */
2967 for (addr = addrlist; addr != NULL; addr = addr->next)
2968 addr->transport_return = FAIL;
2972 /* In the normal, non-wrapper case, add a standard message to each deferred
2973 address if there hasn't been an error, that is, if it hasn't actually been
2974 tried this time. The variable "expired" will be FALSE if any deliveries were
2975 actually tried, or if there was at least one host that was not expired. That
2976 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
2977 a delivery has been tried, an error code will be set, and the failing of the
2978 message is handled by the retry code later.
2980 If queue_smtp is set, or this transport was called to send a subsequent message
2981 down an existing TCP/IP connection, and something caused the host not to be
2982 found, we end up here, but can detect these cases and handle them specially. */
2984 for (addr = addrlist; addr != NULL; addr = addr->next)
2986 /* If host is not NULL, it means that we stopped processing the host list
2987 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
2988 means we need to behave as if some hosts were skipped because their retry
2989 time had not come. Specifically, this prevents the address from timing out.
2990 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
2991 hosts were tried. */
2995 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
2998 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
2999 "hosts were tried\n");
3004 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
3005 setflag(addr, af_retry_skipped);
3009 if (queue_smtp) /* no deliveries attempted */
3011 addr->transport_return = DEFER;
3012 addr->basic_errno = 0;
3013 addr->message = US"SMTP delivery explicitly queued";
3016 else if (addr->transport_return == DEFER &&
3017 (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0) &&
3018 addr->message == NULL)
3020 addr->basic_errno = ERRNO_HRETRY;
3021 if (continue_hostname != NULL)
3023 addr->message = US"no host found for existing SMTP connection";
3027 setflag(addr, af_pass_message); /* This is not a security risk */
3028 addr->message = (ob->delay_after_cutoff)?
3029 US"retry time not reached for any host after a long failure period" :
3030 US"all hosts have been failing for a long time and were last tried "
3031 "after this message arrived";
3033 /* If we are already using fallback hosts, or there are no fallback hosts
3034 defined, convert the result to FAIL to cause a bounce. */
3036 if (addr->host_list == addr->fallback_hosts ||
3037 addr->fallback_hosts == NULL)
3038 addr->transport_return = FAIL;
3042 if (hosts_retry == hosts_total)
3043 addr->message = US"retry time not reached for any host";
3044 else if (hosts_fail == hosts_total)
3045 addr->message = US"all host address lookups failed permanently";
3046 else if (hosts_defer == hosts_total)
3047 addr->message = US"all host address lookups failed temporarily";
3048 else if (hosts_serial == hosts_total)
3049 addr->message = US"connection limit reached for all hosts";
3050 else if (hosts_fail+hosts_defer == hosts_total)
3051 addr->message = US"all host address lookups failed";
3052 else addr->message = US"some host address lookups failed and retry time "
3053 "not reached for other hosts or connection limit reached";
3058 /* Update the database which keeps information about which messages are waiting
3059 for which hosts to become available. For some message-specific errors, the
3060 update_waiting flag is turned off because we don't want follow-on deliveries in
3063 if (update_waiting) transport_update_waiting(hostlist, tblock->name);
3067 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3069 return TRUE; /* Each address has its status */
3072 /* End of transport/smtp.c */