1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2012 */
6 /* See the file NOTICE for conditions of use and distribution. */
12 #define PENDING_DEFER (PENDING + DEFER)
13 #define PENDING_OK (PENDING + OK)
16 /* Options specific to the smtp transport. This transport also supports LMTP
17 over TCP/IP. The options must be in alphabetic order (note that "_" comes
18 before the lower case letters). Some live in the transport_instance block so as
19 to be publicly visible; these are flagged with opt_public. */
21 optionlist smtp_transport_options[] = {
22 { "address_retry_include_sender", opt_bool,
23 (void *)offsetof(smtp_transport_options_block, address_retry_include_sender) },
24 { "allow_localhost", opt_bool,
25 (void *)offsetof(smtp_transport_options_block, allow_localhost) },
26 { "authenticated_sender", opt_stringptr,
27 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
28 { "authenticated_sender_force", opt_bool,
29 (void *)offsetof(smtp_transport_options_block, authenticated_sender_force) },
30 { "command_timeout", opt_time,
31 (void *)offsetof(smtp_transport_options_block, command_timeout) },
32 { "connect_timeout", opt_time,
33 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
34 { "connection_max_messages", opt_int | opt_public,
35 (void *)offsetof(transport_instance, connection_max_messages) },
36 { "data_timeout", opt_time,
37 (void *)offsetof(smtp_transport_options_block, data_timeout) },
38 { "delay_after_cutoff", opt_bool,
39 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
41 { "dkim_canon", opt_stringptr,
42 (void *)offsetof(smtp_transport_options_block, dkim_canon) },
43 { "dkim_domain", opt_stringptr,
44 (void *)offsetof(smtp_transport_options_block, dkim_domain) },
45 { "dkim_private_key", opt_stringptr,
46 (void *)offsetof(smtp_transport_options_block, dkim_private_key) },
47 { "dkim_selector", opt_stringptr,
48 (void *)offsetof(smtp_transport_options_block, dkim_selector) },
49 { "dkim_sign_headers", opt_stringptr,
50 (void *)offsetof(smtp_transport_options_block, dkim_sign_headers) },
51 { "dkim_strict", opt_stringptr,
52 (void *)offsetof(smtp_transport_options_block, dkim_strict) },
54 { "dns_qualify_single", opt_bool,
55 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
56 { "dns_search_parents", opt_bool,
57 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
58 { "dscp", opt_stringptr,
59 (void *)offsetof(smtp_transport_options_block, dscp) },
60 { "fallback_hosts", opt_stringptr,
61 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
62 { "final_timeout", opt_time,
63 (void *)offsetof(smtp_transport_options_block, final_timeout) },
64 { "gethostbyname", opt_bool,
65 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
67 /* These are no longer honoured, as of Exim 4.80; for now, we silently
68 ignore; a later release will warn, and a later-still release will remove
69 these options, so that using them becomes an error. */
70 { "gnutls_require_kx", opt_stringptr,
71 (void *)offsetof(smtp_transport_options_block, gnutls_require_kx) },
72 { "gnutls_require_mac", opt_stringptr,
73 (void *)offsetof(smtp_transport_options_block, gnutls_require_mac) },
74 { "gnutls_require_protocols", opt_stringptr,
75 (void *)offsetof(smtp_transport_options_block, gnutls_require_proto) },
77 { "helo_data", opt_stringptr,
78 (void *)offsetof(smtp_transport_options_block, helo_data) },
79 { "hosts", opt_stringptr,
80 (void *)offsetof(smtp_transport_options_block, hosts) },
81 { "hosts_avoid_esmtp", opt_stringptr,
82 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
83 { "hosts_avoid_pipelining", opt_stringptr,
84 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
86 { "hosts_avoid_tls", opt_stringptr,
87 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
89 { "hosts_max_try", opt_int,
90 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
91 { "hosts_max_try_hardlimit", opt_int,
92 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
94 { "hosts_nopass_tls", opt_stringptr,
95 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
97 { "hosts_override", opt_bool,
98 (void *)offsetof(smtp_transport_options_block, hosts_override) },
99 { "hosts_randomize", opt_bool,
100 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
101 { "hosts_require_auth", opt_stringptr,
102 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
104 # if defined EXPERIMENTAL_OCSP
105 { "hosts_require_ocsp", opt_stringptr,
106 (void *)offsetof(smtp_transport_options_block, hosts_require_ocsp) },
108 { "hosts_require_tls", opt_stringptr,
109 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
111 { "hosts_try_auth", opt_stringptr,
112 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
113 #ifdef EXPERIMENTAL_PRDR
114 { "hosts_try_prdr", opt_stringptr,
115 (void *)offsetof(smtp_transport_options_block, hosts_try_prdr) },
118 { "hosts_verify_avoid_tls", opt_stringptr,
119 (void *)offsetof(smtp_transport_options_block, hosts_verify_avoid_tls) },
121 { "interface", opt_stringptr,
122 (void *)offsetof(smtp_transport_options_block, interface) },
123 { "keepalive", opt_bool,
124 (void *)offsetof(smtp_transport_options_block, keepalive) },
125 { "lmtp_ignore_quota", opt_bool,
126 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
127 { "max_rcpt", opt_int | opt_public,
128 (void *)offsetof(transport_instance, max_addresses) },
129 { "multi_domain", opt_bool | opt_public,
130 (void *)offsetof(transport_instance, multi_domain) },
131 { "port", opt_stringptr,
132 (void *)offsetof(smtp_transport_options_block, port) },
133 { "protocol", opt_stringptr,
134 (void *)offsetof(smtp_transport_options_block, protocol) },
135 { "retry_include_ip_address", opt_bool,
136 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
137 { "serialize_hosts", opt_stringptr,
138 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
139 { "size_addition", opt_int,
140 (void *)offsetof(smtp_transport_options_block, size_addition) }
142 ,{ "tls_certificate", opt_stringptr,
143 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
144 { "tls_crl", opt_stringptr,
145 (void *)offsetof(smtp_transport_options_block, tls_crl) },
146 { "tls_dh_min_bits", opt_int,
147 (void *)offsetof(smtp_transport_options_block, tls_dh_min_bits) },
148 { "tls_privatekey", opt_stringptr,
149 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
150 { "tls_require_ciphers", opt_stringptr,
151 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
152 { "tls_sni", opt_stringptr,
153 (void *)offsetof(smtp_transport_options_block, tls_sni) },
154 { "tls_tempfail_tryclear", opt_bool,
155 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
156 { "tls_verify_certificates", opt_stringptr,
157 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) }
161 /* Size of the options list. An extern variable has to be used so that its
162 address can appear in the tables drtables.c. */
164 int smtp_transport_options_count =
165 sizeof(smtp_transport_options)/sizeof(optionlist);
167 /* Default private options block for the smtp transport. */
169 smtp_transport_options_block smtp_transport_option_defaults = {
171 NULL, /* fallback_hosts */
173 NULL, /* fallback_hostlist */
174 NULL, /* authenticated_sender */
175 US"$primary_hostname", /* helo_data */
176 NULL, /* interface */
178 US"smtp", /* protocol */
180 NULL, /* serialize_hosts */
181 NULL, /* hosts_try_auth */
182 NULL, /* hosts_require_auth */
183 #ifdef EXPERIMENTAL_PRDR
184 NULL, /* hosts_try_prdr */
186 #ifdef EXPERIMENTAL_OCSP
187 NULL, /* hosts_require_ocsp */
189 NULL, /* hosts_require_tls */
190 NULL, /* hosts_avoid_tls */
191 US"*", /* hosts_verify_avoid_tls */
192 NULL, /* hosts_avoid_pipelining */
193 NULL, /* hosts_avoid_esmtp */
194 NULL, /* hosts_nopass_tls */
195 5*60, /* command_timeout */
196 5*60, /* connect_timeout; shorter system default overrides */
197 5*60, /* data timeout */
198 10*60, /* final timeout */
199 1024, /* size_addition */
200 5, /* hosts_max_try */
201 50, /* hosts_max_try_hardlimit */
202 TRUE, /* address_retry_include_sender */
203 FALSE, /* allow_localhost */
204 FALSE, /* authenticated_sender_force */
205 FALSE, /* gethostbyname */
206 TRUE, /* dns_qualify_single */
207 FALSE, /* dns_search_parents */
208 TRUE, /* delay_after_cutoff */
209 FALSE, /* hosts_override */
210 FALSE, /* hosts_randomize */
211 TRUE, /* keepalive */
212 FALSE, /* lmtp_ignore_quota */
213 TRUE /* retry_include_ip_address */
215 ,NULL, /* tls_certificate */
217 NULL, /* tls_privatekey */
218 NULL, /* tls_require_ciphers */
219 NULL, /* gnutls_require_kx */
220 NULL, /* gnutls_require_mac */
221 NULL, /* gnutls_require_proto */
223 NULL, /* tls_verify_certificates */
224 EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
225 /* tls_dh_min_bits */
226 TRUE /* tls_tempfail_tryclear */
229 ,NULL, /* dkim_canon */
230 NULL, /* dkim_domain */
231 NULL, /* dkim_private_key */
232 NULL, /* dkim_selector */
233 NULL, /* dkim_sign_headers */
234 NULL /* dkim_strict */
241 static uschar *smtp_command; /* Points to last cmd for error messages */
242 static uschar *mail_command; /* Points to MAIL cmd for error messages */
243 static BOOL update_waiting; /* TRUE to update the "wait" database */
246 /*************************************************
247 * Setup entry point *
248 *************************************************/
250 /* This function is called when the transport is about to be used,
251 but before running it in a sub-process. It is used for two things:
253 (1) To set the fallback host list in addresses, when delivering.
254 (2) To pass back the interface, port, protocol, and other options, for use
255 during callout verification.
258 tblock pointer to the transport instance block
259 addrlist list of addresses about to be transported
260 tf if not NULL, pointer to block in which to return options
261 uid the uid that will be set (not used)
262 gid the gid that will be set (not used)
263 errmsg place for error message (not used)
265 Returns: OK always (FAIL, DEFER not used)
269 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
270 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
272 smtp_transport_options_block *ob =
273 (smtp_transport_options_block *)(tblock->options_block);
275 errmsg = errmsg; /* Keep picky compilers happy */
279 /* Pass back options if required. This interface is getting very messy. */
283 tf->interface = ob->interface;
285 tf->protocol = ob->protocol;
286 tf->hosts = ob->hosts;
287 tf->hosts_override = ob->hosts_override;
288 tf->hosts_randomize = ob->hosts_randomize;
289 tf->gethostbyname = ob->gethostbyname;
290 tf->qualify_single = ob->dns_qualify_single;
291 tf->search_parents = ob->dns_search_parents;
292 tf->helo_data = ob->helo_data;
295 /* Set the fallback host list for all the addresses that don't have fallback
296 host lists, provided that the local host wasn't present in the original host
299 if (!testflag(addrlist, af_local_host_removed))
301 for (; addrlist != NULL; addrlist = addrlist->next)
302 if (addrlist->fallback_hosts == NULL)
303 addrlist->fallback_hosts = ob->fallback_hostlist;
311 /*************************************************
312 * Initialization entry point *
313 *************************************************/
315 /* Called for each instance, after its options have been read, to
316 enable consistency checks to be done, or anything else that needs
319 Argument: pointer to the transport instance block
324 smtp_transport_init(transport_instance *tblock)
326 smtp_transport_options_block *ob =
327 (smtp_transport_options_block *)(tblock->options_block);
329 /* Retry_use_local_part defaults FALSE if unset */
331 if (tblock->retry_use_local_part == TRUE_UNSET)
332 tblock->retry_use_local_part = FALSE;
334 /* Set the default port according to the protocol */
336 if (ob->port == NULL)
337 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
338 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
340 /* Set up the setup entry point, to be called before subprocesses for this
343 tblock->setup = smtp_transport_setup;
345 /* Complain if any of the timeouts are zero. */
347 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
348 ob->final_timeout <= 0)
349 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
350 "command, data, or final timeout value is zero for %s transport",
353 /* If hosts_override is set and there are local hosts, set the global
354 flag that stops verify from showing router hosts. */
356 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
358 /* If there are any fallback hosts listed, build a chain of host items
359 for them, but do not do any lookups at this time. */
361 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
368 /*************************************************
369 * Set delivery info into all active addresses *
370 *************************************************/
372 /* Only addresses whose status is >= PENDING are relevant. A lesser
373 status means that an address is not currently being processed.
376 addrlist points to a chain of addresses
377 errno_value to put in each address's errno field
378 msg to put in each address's message field
379 rc to put in each address's transport_return field
380 pass_message if TRUE, set the "pass message" flag in the address
382 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
383 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
384 this particular type of timeout.
390 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
395 if (errno_value == ERRNO_CONNECTTIMEOUT)
397 errno_value = ETIMEDOUT;
398 orvalue = RTEF_CTOUT;
400 for (addr = addrlist; addr != NULL; addr = addr->next)
402 if (addr->transport_return < PENDING) continue;
403 addr->basic_errno = errno_value;
404 addr->more_errno |= orvalue;
408 if (pass_message) setflag(addr, af_pass_message);
410 addr->transport_return = rc;
416 /*************************************************
417 * Check an SMTP response *
418 *************************************************/
420 /* This function is given an errno code and the SMTP response buffer
421 to analyse, together with the host identification for generating messages. It
422 sets an appropriate message and puts the first digit of the response code into
423 the yield variable. If no response was actually read, a suitable digit is
427 host the current host, to get its name for messages
428 errno_value pointer to the errno value
429 more_errno from the top address for use with ERRNO_FILTER_FAIL
430 buffer the SMTP response buffer
431 yield where to put a one-digit SMTP response code
432 message where to put an errror message
433 pass_message set TRUE if message is an SMTP response
435 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
438 static BOOL check_response(host_item *host, int *errno_value, int more_errno,
439 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
443 if (smtp_use_pipelining &&
444 (Ustrcmp(smtp_command, "MAIL") == 0 ||
445 Ustrcmp(smtp_command, "RCPT") == 0 ||
446 Ustrcmp(smtp_command, "DATA") == 0))
449 *yield = '4'; /* Default setting is to give a temporary error */
451 /* Handle response timeout */
453 if (*errno_value == ETIMEDOUT)
455 *message = US string_sprintf("SMTP timeout while connected to %s [%s] "
456 "after %s%s", host->name, host->address, pl, smtp_command);
457 if (transport_count > 0)
458 *message = US string_sprintf("%s (%d bytes written)", *message,
463 /* Handle malformed SMTP response */
465 if (*errno_value == ERRNO_SMTPFORMAT)
467 uschar *malfresp = string_printing(buffer);
468 while (isspace(*malfresp)) malfresp++;
470 *message = string_sprintf("Malformed SMTP reply (an empty line) from "
471 "%s [%s] in response to %s%s", host->name, host->address, pl,
474 *message = string_sprintf("Malformed SMTP reply from %s [%s] in response "
475 "to %s%s: %s", host->name, host->address, pl, smtp_command, malfresp);
479 /* Handle a failed filter process error; can't send QUIT as we mustn't
482 if (*errno_value == ERRNO_FILTER_FAIL)
484 *message = US string_sprintf("transport filter process failed (%d)%s",
486 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
490 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
493 if (*errno_value == ERRNO_CHHEADER_FAIL)
496 US string_sprintf("failed to expand headers_add or headers_remove: %s",
497 expand_string_message);
501 /* Handle failure to write a complete data block */
503 if (*errno_value == ERRNO_WRITEINCOMPLETE)
505 *message = US string_sprintf("failed to write a data block");
509 /* Handle error responses from the remote mailer. */
513 uschar *s = string_printing(buffer);
514 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
515 "host %s [%s]: %s", pl, smtp_command, host->name, host->address, s);
516 *pass_message = TRUE;
521 /* No data was read. If there is no errno, this must be the EOF (i.e.
522 connection closed) case, which causes deferral. An explicit connection reset
523 error has the same effect. Otherwise, put the host's identity in the message,
524 leaving the errno value to be interpreted as well. In all cases, we have to
525 assume the connection is now dead. */
527 if (*errno_value == 0 || *errno_value == ECONNRESET)
529 *errno_value = ERRNO_SMTPCLOSED;
530 *message = US string_sprintf("Remote host %s [%s] closed connection "
531 "in response to %s%s", host->name, host->address, pl, smtp_command);
533 else *message = US string_sprintf("%s [%s]", host->name, host->address);
540 /*************************************************
541 * Write error message to logs *
542 *************************************************/
544 /* This writes to the main log and to the message log.
547 addr the address item containing error information
548 host the current host
554 write_logs(address_item *addr, host_item *host)
556 if (addr->message != NULL)
558 uschar *message = addr->message;
559 if (addr->basic_errno > 0)
560 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
561 log_write(0, LOG_MAIN, "%s", message);
562 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
567 ((log_extra_selector & LX_outgoing_port) != 0)?
568 string_sprintf("%s [%s]:%d", host->name, host->address,
569 (host->port == PORT_NONE)? 25 : host->port)
571 string_sprintf("%s [%s]", host->name, host->address);
572 log_write(0, LOG_MAIN, "%s %s", msg, strerror(addr->basic_errno));
573 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), msg,
574 strerror(addr->basic_errno));
580 /*************************************************
581 * Synchronize SMTP responses *
582 *************************************************/
584 /* This function is called from smtp_deliver() to receive SMTP responses from
585 the server, and match them up with the commands to which they relate. When
586 PIPELINING is not in use, this function is called after every command, and is
587 therefore somewhat over-engineered, but it is simpler to use a single scheme
588 that works both with and without PIPELINING instead of having two separate sets
591 The set of commands that are buffered up with pipelining may start with MAIL
592 and may end with DATA; in between are RCPT commands that correspond to the
593 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
594 etc.) are never buffered.
596 Errors after MAIL or DATA abort the whole process leaving the response in the
597 buffer. After MAIL, pending responses are flushed, and the original command is
598 re-instated in big_buffer for error messages. For RCPT commands, the remote is
599 permitted to reject some recipient addresses while accepting others. However
600 certain errors clearly abort the whole process. Set the value in
601 transport_return to PENDING_OK if the address is accepted. If there is a
602 subsequent general error, it will get reset accordingly. If not, it will get
603 converted to OK at the end.
606 addrlist the complete address list
607 include_affixes TRUE if affixes include in RCPT
608 sync_addr ptr to the ptr of the one to start scanning at (updated)
609 host the host we are connected to
610 count the number of responses to read
612 include_sender true if 4xx retry is to include the sender it its key
613 pending_MAIL true if the first response is for MAIL
614 pending_DATA 0 if last command sent was not DATA
615 +1 if previously had a good recipient
616 -1 if not previously had a good recipient
617 inblock incoming SMTP block
618 timeout timeout value
619 buffer buffer for reading response
620 buffsize size of buffer
622 Returns: 3 if at least one address had 2xx and one had 5xx
623 2 if at least one address had 5xx but none had 2xx
624 1 if at least one host had a 2xx response, but none had 5xx
625 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
626 -1 timeout while reading RCPT response
627 -2 I/O or other non-response error for RCPT
628 -3 DATA or MAIL failed - errno and buffer set
632 sync_responses(address_item *addrlist, BOOL include_affixes,
633 address_item **sync_addr, host_item *host, int count,
634 BOOL address_retry_include_sender, BOOL pending_MAIL,
635 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
638 address_item *addr = *sync_addr;
641 /* Handle the response for a MAIL command. On error, reinstate the original
642 command in big_buffer for error message use, and flush any further pending
643 responses before returning, except after I/O errors and timeouts. */
648 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
650 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
651 if (errno == 0 && buffer[0] != 0)
653 uschar flushbuffer[4096];
655 if (buffer[0] == '4')
657 save_errno = ERRNO_MAIL4XX;
658 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
662 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
664 && (errno != 0 || flushbuffer[0] == 0))
673 if (pending_DATA) count--; /* Number of RCPT responses to come */
675 /* Read and handle the required number of RCPT responses, matching each one up
676 with an address by scanning for the next address whose status is PENDING_DEFER.
681 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
683 /* The address was accepted */
685 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
688 addr->transport_return = PENDING_OK;
690 /* If af_dr_retry_exists is set, there was a routing delay on this address;
691 ensure that any address-specific retry record is expunged. We do this both
692 for the basic key and for the version that also includes the sender. */
694 if (testflag(addr, af_dr_retry_exists))
696 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
698 retry_add_item(addr, altkey, rf_delete);
699 retry_add_item(addr, addr->address_retry_key, rf_delete);
703 /* Timeout while reading the response */
705 else if (errno == ETIMEDOUT)
707 int save_errno = errno;
708 uschar *message = string_sprintf("SMTP timeout while connected to %s [%s] "
709 "after RCPT TO:<%s>", host->name, host->address,
710 transport_rcpt_address(addr, include_affixes));
711 set_errno(addrlist, save_errno, message, DEFER, FALSE);
712 retry_add_item(addr, addr->address_retry_key, 0);
713 update_waiting = FALSE;
717 /* Handle other errors in obtaining an SMTP response by returning -1. This
718 will cause all the addresses to be deferred. Restore the SMTP command in
719 big_buffer for which we are checking the response, so the error message
722 else if (errno != 0 || buffer[0] == 0)
724 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
725 transport_rcpt_address(addr, include_affixes));
729 /* Handle SMTP permanent and temporary response codes. */
734 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
735 "host %s [%s]: %s", transport_rcpt_address(addr, include_affixes),
736 host->name, host->address, string_printing(buffer));
737 setflag(addr, af_pass_message);
738 deliver_msglog("%s %s\n", tod_stamp(tod_log), addr->message);
740 /* The response was 5xx */
742 if (buffer[0] == '5')
744 addr->transport_return = FAIL;
748 /* The response was 4xx */
752 addr->transport_return = DEFER;
753 addr->basic_errno = ERRNO_RCPT4XX;
754 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
756 /* Log temporary errors if there are more hosts to be tried. */
758 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", addr->message);
760 /* Do not put this message on the list of those waiting for specific
761 hosts, as otherwise it is likely to be tried too often. */
763 update_waiting = FALSE;
765 /* Add a retry item for the address so that it doesn't get tried again
766 too soon. If address_retry_include_sender is true, add the sender address
769 if (address_retry_include_sender)
771 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
773 retry_add_item(addr, altkey, 0);
775 else retry_add_item(addr, addr->address_retry_key, 0);
778 } /* Loop for next RCPT response */
780 /* Update where to start at for the next block of responses, unless we
781 have already handled all the addresses. */
783 if (addr != NULL) *sync_addr = addr->next;
785 /* Handle a response to DATA. If we have not had any good recipients, either
786 previously or in this block, the response is ignored. */
788 if (pending_DATA != 0 &&
789 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
794 if (pending_DATA > 0 || (yield & 1) != 0)
796 if (errno == 0 && buffer[0] == '4')
798 errno = ERRNO_DATA4XX;
799 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
803 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
804 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
805 "is in use and there were no good recipients\n", msg);
808 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
809 present) received 3xx. If any RCPTs were handled and yielded anything other
810 than 4xx, yield will be set non-zero. */
817 /*************************************************
818 * Deliver address list to given host *
819 *************************************************/
821 /* If continue_hostname is not null, we get here only when continuing to
822 deliver down an existing channel. The channel was passed as the standard
823 input. TLS is never active on a passed channel; the previous process always
824 closes it down before passing the connection on.
826 Otherwise, we have to make a connection to the remote host, and do the
827 initial protocol exchange.
829 When running as an MUA wrapper, if the sender or any recipient is rejected,
830 temporarily or permanently, we force failure for all recipients.
833 addrlist chain of potential addresses to deliver; only those whose
834 transport_return field is set to PENDING_DEFER are currently
835 being processed; others should be skipped - they have either
836 been delivered to an earlier host or IP address, or been
837 failed by one of them.
838 host host to deliver to
839 host_af AF_INET or AF_INET6
840 port default TCP/IP port to use, in host byte order
841 interface interface to bind to, or NULL
842 tblock transport instance block
843 copy_host TRUE if host set in addr->host_used must be copied, because
844 it is specific to this call of the transport
845 message_defer set TRUE if yield is OK, but all addresses were deferred
846 because of a non-recipient, non-host failure, that is, a
847 4xx response to MAIL FROM, DATA, or ".". This is a defer
848 that is specific to the message.
849 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
850 a second attempt after TLS initialization fails
852 Returns: OK - the connection was made and the delivery attempted;
853 the result for each address is in its data block.
854 DEFER - the connection could not be made, or something failed
855 while setting up the SMTP session, or there was a
856 non-message-specific error, such as a timeout.
857 ERROR - a filter command is specified for this transport,
858 and there was a problem setting it up; OR helo_data
859 or add_headers or authenticated_sender is specified
860 for this transport, and the string failed to expand
864 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
865 uschar *interface, transport_instance *tblock, BOOL copy_host,
866 BOOL *message_defer, BOOL suppress_tls)
869 address_item *sync_addr;
870 address_item *first_addr = addrlist;
875 time_t start_delivery_time = time(NULL);
876 smtp_transport_options_block *ob =
877 (smtp_transport_options_block *)(tblock->options_block);
878 BOOL lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
879 BOOL smtps = strcmpic(ob->protocol, US"smtps") == 0;
881 BOOL send_rset = TRUE;
882 BOOL send_quit = TRUE;
883 BOOL setting_up = TRUE;
884 BOOL completed_address = FALSE;
887 BOOL pass_message = FALSE;
888 #ifdef EXPERIMENTAL_PRDR
889 BOOL prdr_offered = FALSE;
892 smtp_inblock inblock;
893 smtp_outblock outblock;
894 int max_rcpt = tblock->max_addresses;
895 uschar *igquotstr = US"";
896 uschar *local_authenticated_sender = authenticated_sender;
897 uschar *helo_data = NULL;
898 uschar *message = NULL;
899 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
902 uschar inbuffer[4096];
903 uschar outbuffer[1024];
905 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
907 *message_defer = FALSE;
908 smtp_command = US"initial connection";
909 if (max_rcpt == 0) max_rcpt = 999999;
911 /* Set up the buffer for reading SMTP response packets. */
913 inblock.buffer = inbuffer;
914 inblock.buffersize = sizeof(inbuffer);
915 inblock.ptr = inbuffer;
916 inblock.ptrend = inbuffer;
918 /* Set up the buffer for holding SMTP commands while pipelining */
920 outblock.buffer = outbuffer;
921 outblock.buffersize = sizeof(outbuffer);
922 outblock.ptr = outbuffer;
923 outblock.cmd_count = 0;
924 outblock.authenticating = FALSE;
926 /* Reset the parameters of a TLS session. */
929 tls_in.cipher = NULL; /* for back-compatible behaviour */
930 tls_in.peerdn = NULL;
931 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
936 tls_out.cipher = NULL; /* the one we may use for this transport */
937 tls_out.peerdn = NULL;
938 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
945 set_errno(addrlist, 0, US"TLS support not available", DEFER, FALSE);
950 /* Make a connection to the host if this isn't a continued delivery, and handle
951 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
952 specially so they can be identified for retries. */
954 if (continue_hostname == NULL)
956 inblock.sock = outblock.sock =
957 smtp_connect(host, host_af, port, interface, ob->connect_timeout,
958 ob->keepalive, ob->dscp); /* This puts port into host->port */
960 if (inblock.sock < 0)
962 set_errno(addrlist, (errno == ETIMEDOUT)? ERRNO_CONNECTTIMEOUT : errno,
967 /* Expand the greeting message while waiting for the initial response. (Makes
968 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
969 delayed till here so that $sending_interface and $sending_port are set. */
971 helo_data = expand_string(ob->helo_data);
973 /* The first thing is to wait for an initial OK response. The dreaded "goto"
974 is nevertheless a reasonably clean way of programming this kind of logic,
975 where you want to escape on any error. */
979 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
980 ob->command_timeout)) goto RESPONSE_FAILED;
982 /* Now check if the helo_data expansion went well, and sign off cleanly if
985 if (helo_data == NULL)
987 uschar *message = string_sprintf("failed to expand helo_data: %s",
988 expand_string_message);
989 set_errno(addrlist, 0, message, DEFER, FALSE);
995 /** Debugging without sending a message
996 addrlist->transport_return = DEFER;
1000 /* Errors that occur after this point follow an SMTP command, which is
1001 left in big_buffer by smtp_write_command() for use in error messages. */
1003 smtp_command = big_buffer;
1005 /* Tell the remote who we are...
1007 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1008 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1009 greeting is of this form. The assumption was that the far end supports it
1010 properly... but experience shows that there are some that give 5xx responses,
1011 even though the banner includes "ESMTP" (there's a bloody-minded one that
1012 says "ESMTP not spoken here"). Cope with that case.
1014 September 2000: Time has passed, and it seems reasonable now to always send
1015 EHLO at the start. It is also convenient to make the change while installing
1018 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1019 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1020 would be no way to send out the mails, so there is now a host list
1021 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1022 PIPELINING problem as well. Maybe it can also be useful to cure other
1023 problems with broken servers.
1025 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1026 Then somebody tried it with a Microsoft mailer... It seems that all other
1027 mailers use upper case for some reason (the RFC is quite clear about case
1028 independence) so, for peace of mind, I gave in. */
1030 esmtp = verify_check_this_host(&(ob->hosts_avoid_esmtp), NULL,
1031 host->name, host->address, NULL) != OK;
1033 /* Alas; be careful, since this goto is not an error-out, so conceivably
1034 we might set data between here and the target which we assume to exist
1035 and be usable. I can see this coming back to bite us. */
1040 suppress_tls = FALSE;
1041 ob->tls_tempfail_tryclear = FALSE;
1042 smtp_command = US"SSL-on-connect";
1049 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1050 lmtp? "LHLO" : "EHLO", helo_data) < 0)
1052 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1053 ob->command_timeout))
1055 if (errno != 0 || buffer[0] == 0 || lmtp) goto RESPONSE_FAILED;
1062 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1067 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1069 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1070 ob->command_timeout)) goto RESPONSE_FAILED;
1073 /* Set IGNOREQUOTA if the response to LHLO specifies support and the
1074 lmtp_ignore_quota option was set. */
1076 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1077 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1078 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1080 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1083 tls_offered = esmtp &&
1084 pcre_exec(regex_STARTTLS, NULL, CS buffer, Ustrlen(buffer), 0,
1085 PCRE_EOPT, NULL, 0) >= 0;
1088 #ifdef EXPERIMENTAL_PRDR
1089 prdr_offered = esmtp &&
1090 (pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(buffer), 0,
1091 PCRE_EOPT, NULL, 0) >= 0) &&
1092 (verify_check_this_host(&(ob->hosts_try_prdr), NULL, host->name,
1093 host->address, NULL) == OK);
1096 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1100 /* For continuing deliveries down the same channel, the socket is the standard
1101 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1102 below). Set up the pointer to where subsequent commands will be left, for
1103 error messages. Note that smtp_use_size and smtp_use_pipelining will have been
1104 set from the command line if they were set in the process that passed the
1109 inblock.sock = outblock.sock = fileno(stdin);
1110 smtp_command = big_buffer;
1111 host->port = port; /* Record the port that was used */
1114 /* If TLS is available on this connection, whether continued or not, attempt to
1115 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1116 send another EHLO - the server may give a different answer in secure mode. We
1117 use a separate buffer for reading the response to STARTTLS so that if it is
1118 negative, the original EHLO data is available for subsequent analysis, should
1119 the client not be required to use TLS. If the response is bad, copy the buffer
1120 for error analysis. */
1123 if (tls_offered && !suppress_tls &&
1124 verify_check_this_host(&(ob->hosts_avoid_tls), NULL, host->name,
1125 host->address, NULL) != OK)
1127 uschar buffer2[4096];
1128 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1131 /* If there is an I/O error, transmission of this message is deferred. If
1132 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1133 false, we also defer. However, if there is a temporary rejection of STARTTLS
1134 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1135 STARTTLS, we carry on. This means we will try to send the message in clear,
1136 unless the host is in hosts_require_tls (tested below). */
1138 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1139 ob->command_timeout))
1141 if (errno != 0 || buffer2[0] == 0 ||
1142 (buffer2[0] == '4' && !ob->tls_tempfail_tryclear))
1144 Ustrncpy(buffer, buffer2, sizeof(buffer));
1145 goto RESPONSE_FAILED;
1149 /* STARTTLS accepted: try to negotiate a TLS session. */
1154 int rc = tls_client_start(inblock.sock,
1157 ob->tls_certificate,
1160 ob->tls_verify_certificates,
1162 ob->tls_require_ciphers,
1163 #ifdef EXPERIMENTAL_OCSP
1164 ob->hosts_require_ocsp,
1166 ob->tls_dh_min_bits,
1167 ob->command_timeout);
1169 /* TLS negotiation failed; give an error. From outside, this function may
1170 be called again to try in clear on a new connection, if the options permit
1171 it for this host. */
1175 save_errno = ERRNO_TLSFAILURE;
1176 message = US"failure while setting up TLS session";
1181 /* TLS session is set up */
1183 for (addr = addrlist; addr != NULL; addr = addr->next)
1185 if (addr->transport_return == PENDING_DEFER)
1187 addr->cipher = tls_out.cipher;
1188 addr->peerdn = tls_out.peerdn;
1194 /* if smtps, we'll have smtp_command set to something else; always safe to
1196 smtp_command = big_buffer;
1198 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1199 helo_data is null, we are dealing with a connection that was passed from
1200 another process, and so we won't have expanded helo_data above. We have to
1201 expand it here. $sending_ip_address and $sending_port are set up right at the
1202 start of the Exim process (in exim.c). */
1204 if (tls_out.active >= 0)
1207 if (helo_data == NULL)
1209 helo_data = expand_string(ob->helo_data);
1210 if (helo_data == NULL)
1212 uschar *message = string_sprintf("failed to expand helo_data: %s",
1213 expand_string_message);
1214 set_errno(addrlist, 0, message, DEFER, FALSE);
1220 /* For SMTPS we need to wait for the initial OK response. */
1223 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1224 ob->command_timeout)) goto RESPONSE_FAILED;
1228 greeting_cmd = "EHLO";
1231 greeting_cmd = "HELO";
1233 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1236 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1237 lmtp? "LHLO" : greeting_cmd, helo_data) < 0)
1239 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1240 ob->command_timeout))
1241 goto RESPONSE_FAILED;
1244 /* If the host is required to use a secure channel, ensure that we
1247 else if (verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
1248 host->address, NULL) == OK)
1250 save_errno = ERRNO_TLSREQUIRED;
1251 message = string_sprintf("a TLS session is required for %s [%s], but %s",
1252 host->name, host->address,
1253 tls_offered? "an attempt to start TLS failed" :
1254 "the server did not offer TLS support");
1259 /* If TLS is active, we have just started it up and re-done the EHLO command,
1260 so its response needs to be analyzed. If TLS is not active and this is a
1261 continued session down a previously-used socket, we haven't just done EHLO, so
1264 if (continue_hostname == NULL
1266 || tls_out.active >= 0
1271 uschar *fail_reason = US"server did not advertise AUTH support";
1273 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
1274 lmtp_ignore_quota option was set. */
1276 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1277 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1278 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1280 /* If the response to EHLO specified support for the SIZE parameter, note
1281 this, provided size_addition is non-negative. */
1283 smtp_use_size = esmtp && ob->size_addition >= 0 &&
1284 pcre_exec(regex_SIZE, NULL, CS buffer, Ustrlen(CS buffer), 0,
1285 PCRE_EOPT, NULL, 0) >= 0;
1287 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
1288 the current host, esmtp will be false, so PIPELINING can never be used. If
1289 the current host matches hosts_avoid_pipelining, don't do it. */
1291 smtp_use_pipelining = esmtp &&
1292 verify_check_this_host(&(ob->hosts_avoid_pipelining), NULL, host->name,
1293 host->address, NULL) != OK &&
1294 pcre_exec(regex_PIPELINING, NULL, CS buffer, Ustrlen(CS buffer), 0,
1295 PCRE_EOPT, NULL, 0) >= 0;
1297 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
1298 smtp_use_pipelining? "" : "not ");
1300 #ifdef EXPERIMENTAL_PRDR
1301 prdr_offered = esmtp &&
1302 pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(CS buffer), 0,
1303 PCRE_EOPT, NULL, 0) >= 0 &&
1304 verify_check_this_host(&(ob->hosts_try_prdr), NULL, host->name,
1305 host->address, NULL) == OK;
1308 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1311 /* Note if the response to EHLO specifies support for the AUTH extension.
1312 If it has, check that this host is one we want to authenticate to, and do
1313 the business. The host name and address must be available when the
1314 authenticator's client driver is running. */
1316 smtp_authenticated = FALSE;
1317 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
1318 require_auth = verify_check_this_host(&(ob->hosts_require_auth), NULL,
1319 host->name, host->address, NULL);
1321 if (esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
1323 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
1324 expand_nmax = -1; /* reset */
1326 /* Must not do this check until after we have saved the result of the
1327 regex match above. */
1329 if (require_auth == OK ||
1330 verify_check_this_host(&(ob->hosts_try_auth), NULL, host->name,
1331 host->address, NULL) == OK)
1334 fail_reason = US"no common mechanisms were found";
1336 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1338 /* Scan the configured authenticators looking for one which is configured
1339 for use as a client, which is not suppressed by client_condition, and
1340 whose name matches an authentication mechanism supported by the server.
1341 If one is found, attempt to authenticate by calling its client function.
1344 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1348 (au->client_condition != NULL &&
1349 !expand_check_condition(au->client_condition, au->name,
1350 US"client authenticator")))
1352 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1354 (au->client)? "client_condition is false" :
1355 "not configured as a client");
1359 /* Loop to scan supported server mechanisms */
1364 int len = Ustrlen(au->public_name);
1365 while (isspace(*p)) p++;
1367 if (strncmpic(au->public_name, p, len) != 0 ||
1368 (p[len] != 0 && !isspace(p[len])))
1370 while (*p != 0 && !isspace(*p)) p++;
1374 /* Found data for a listed mechanism. Call its client entry. Set
1375 a flag in the outblock so that data is overwritten after sending so
1376 that reflections don't show it. */
1378 fail_reason = US"authentication attempt(s) failed";
1379 outblock.authenticating = TRUE;
1380 rc = (au->info->clientcode)(au, &inblock, &outblock,
1381 ob->command_timeout, buffer, sizeof(buffer));
1382 outblock.authenticating = FALSE;
1383 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1386 /* A temporary authentication failure must hold up delivery to
1387 this host. After a permanent authentication failure, we carry on
1388 to try other authentication methods. If all fail hard, try to
1389 deliver the message unauthenticated unless require_auth was set. */
1394 smtp_authenticated = TRUE; /* stops the outer loop */
1395 client_authenticator = au->name;
1396 if (au->set_client_id != NULL)
1397 client_authenticated_id = expand_string(au->set_client_id);
1400 /* Failure after writing a command */
1405 /* Failure after reading a response */
1408 if (errno != 0 || buffer[0] != '5') goto RESPONSE_FAILED;
1409 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1410 au->name, host->name, host->address, buffer);
1413 /* Failure by some other means. In effect, the authenticator
1414 decided it wasn't prepared to handle this case. Typically this
1415 is the result of "fail" in an expansion string. Do we need to
1416 log anything here? Feb 2006: a message is now put in the buffer
1417 if logging is required. */
1421 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1422 "authentication H=%s [%s] %s", au->name, host->name,
1423 host->address, buffer);
1426 /* Internal problem, message in buffer. */
1430 set_errno(addrlist, 0, string_copy(buffer), DEFER, FALSE);
1434 break; /* If not authenticated, try next authenticator */
1435 } /* Loop for scanning supported server mechanisms */
1436 } /* Loop for further authenticators */
1440 /* If we haven't authenticated, but are required to, give up. */
1442 if (require_auth == OK && !smtp_authenticated)
1445 set_errno(addrlist, ERRNO_AUTHFAIL,
1446 string_sprintf("authentication required but %s", fail_reason), DEFER,
1452 /* The setting up of the SMTP call is now complete. Any subsequent errors are
1453 message-specific. */
1457 /* If there is a filter command specified for this transport, we can now
1458 set it up. This cannot be done until the identify of the host is known. */
1460 if (tblock->filter_command != NULL)
1464 sprintf(CS buffer, "%.50s transport", tblock->name);
1465 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
1466 TRUE, DEFER, addrlist, buffer, NULL);
1467 transport_filter_timeout = tblock->filter_timeout;
1469 /* On failure, copy the error to all addresses, abandon the SMTP call, and
1474 set_errno(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
1482 /* For messages that have more than the maximum number of envelope recipients,
1483 we want to send several transactions down the same SMTP connection. (See
1484 comments in deliver.c as to how this reconciles, heuristically, with
1485 remote_max_parallel.) This optimization was added to Exim after the following
1486 code was already working. The simplest way to put it in without disturbing the
1487 code was to use a goto to jump back to this point when there is another
1488 transaction to handle. */
1491 sync_addr = first_addr;
1495 completed_address = FALSE;
1498 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
1499 qualification, send it, adding something to the message size to allow for
1500 imprecision and things that get added en route. Exim keeps the number of lines
1501 in a message, so we can give an accurate value for the original message, but we
1502 need some additional to handle added headers. (Double "." characters don't get
1503 included in the count.) */
1510 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
1514 #ifdef EXPERIMENTAL_PRDR
1515 prdr_active = FALSE;
1518 for (addr = first_addr; addr; addr = addr->next)
1519 if (addr->transport_return == PENDING_DEFER)
1521 for (addr = addr->next; addr; addr = addr->next)
1522 if (addr->transport_return == PENDING_DEFER)
1523 { /* at least two recipients to send */
1525 sprintf(CS p, " PRDR"); p += 5;
1526 goto prdr_is_active;
1534 /* If an authenticated_sender override has been specified for this transport
1535 instance, expand it. If the expansion is forced to fail, and there was already
1536 an authenticated_sender for this message, the original value will be used.
1537 Other expansion failures are serious. An empty result is ignored, but there is
1538 otherwise no check - this feature is expected to be used with LMTP and other
1539 cases where non-standard addresses (e.g. without domains) might be required. */
1541 if (ob->authenticated_sender != NULL)
1543 uschar *new = expand_string(ob->authenticated_sender);
1546 if (!expand_string_forcedfail)
1548 uschar *message = string_sprintf("failed to expand "
1549 "authenticated_sender: %s", expand_string_message);
1550 set_errno(addrlist, 0, message, DEFER, FALSE);
1554 else if (new[0] != 0) local_authenticated_sender = new;
1557 /* Add the authenticated sender address if present */
1559 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1560 local_authenticated_sender != NULL)
1562 string_format(p, sizeof(buffer) - (p-buffer), " AUTH=%s",
1563 auth_xtextencode(local_authenticated_sender,
1564 Ustrlen(local_authenticated_sender)));
1565 client_authenticated_sender = string_copy(local_authenticated_sender);
1568 /* From here until we send the DATA command, we can make use of PIPELINING
1569 if the server host supports it. The code has to be able to check the responses
1570 at any point, for when the buffer fills up, so we write it totally generally.
1571 When PIPELINING is off, each command written reports that it has flushed the
1574 pending_MAIL = TRUE; /* The block starts with MAIL */
1576 rc = smtp_write_command(&outblock, smtp_use_pipelining,
1577 "MAIL FROM:<%s>%s\r\n", return_path, buffer);
1578 mail_command = string_copy(big_buffer); /* Save for later error message */
1582 case -1: /* Transmission error */
1585 case +1: /* Block was sent */
1586 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1587 ob->command_timeout))
1589 if (errno == 0 && buffer[0] == '4')
1591 errno = ERRNO_MAIL4XX;
1592 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1594 goto RESPONSE_FAILED;
1596 pending_MAIL = FALSE;
1600 /* Pass over all the relevant recipient addresses for this host, which are the
1601 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
1602 several before we have to read the responses for those seen so far. This
1603 checking is done by a subroutine because it also needs to be done at the end.
1604 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
1605 the next one if not all are sent.
1607 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
1608 last address because we want to abort if any recipients have any kind of
1609 problem, temporary or permanent. We know that all recipient addresses will have
1610 the PENDING_DEFER status, because only one attempt is ever made, and we know
1611 that max_rcpt will be large, so all addresses will be done at once. */
1613 for (addr = first_addr;
1614 address_count < max_rcpt && addr != NULL;
1620 if (addr->transport_return != PENDING_DEFER) continue;
1623 no_flush = smtp_use_pipelining && (!mua_wrapper || addr->next != NULL);
1625 /* Now send the RCPT command, and process outstanding responses when
1626 necessary. After a timeout on RCPT, we just end the function, leaving the
1627 yield as OK, because this error can often mean that there is a problem with
1628 just one address, so we don't want to delay the host. */
1630 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s\r\n",
1631 transport_rcpt_address(addr, tblock->rcpt_include_affixes), igquotstr);
1632 if (count < 0) goto SEND_FAILED;
1635 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
1636 &sync_addr, host, count, ob->address_retry_include_sender,
1637 pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
1640 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1641 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1644 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1645 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1646 case 0: /* No 2xx or 5xx, but no probs */
1649 case -1: goto END_OFF; /* Timeout on RCPT */
1650 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
1652 pending_MAIL = FALSE; /* Dealt with MAIL */
1654 } /* Loop for next address */
1656 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
1657 permanently or temporarily. We should have flushed and synced after the last
1662 address_item *badaddr;
1663 for (badaddr = first_addr; badaddr != NULL; badaddr = badaddr->next)
1665 if (badaddr->transport_return != PENDING_OK) break;
1667 if (badaddr != NULL)
1669 set_errno(addrlist, 0, badaddr->message, FAIL,
1670 testflag(badaddr, af_pass_message));
1675 /* If ok is TRUE, we know we have got at least one good recipient, and must now
1676 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
1677 have a good recipient buffered up if we are pipelining. We don't want to waste
1678 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
1679 are pipelining. The responses are all handled by sync_responses(). */
1681 if (ok || (smtp_use_pipelining && !mua_wrapper))
1683 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
1684 if (count < 0) goto SEND_FAILED;
1685 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
1686 host, count, ob->address_retry_include_sender, pending_MAIL,
1687 ok? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
1689 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1690 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1693 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1694 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1695 case 0: break; /* No 2xx or 5xx, but no probs */
1697 case -1: goto END_OFF; /* Timeout on RCPT */
1698 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
1702 /* Save the first address of the next batch. */
1706 /* If there were no good recipients (but otherwise there have been no
1707 problems), just set ok TRUE, since we have handled address-specific errors
1708 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
1709 for handling the SMTP dot-handling protocol, flagging to apply to headers as
1710 well as body. Set the appropriate timeout value to be used for each chunk.
1711 (Haven't been able to make it work using select() for writing yet.) */
1713 if (!ok) ok = TRUE; else
1715 sigalrm_seen = FALSE;
1716 transport_write_timeout = ob->data_timeout;
1717 smtp_command = US"sending data block"; /* For error messages */
1718 DEBUG(D_transport|D_v)
1719 debug_printf(" SMTP>> writing message and terminating \".\"\n");
1720 transport_count = 0;
1721 #ifndef DISABLE_DKIM
1722 ok = dkim_transport_write_message(addrlist, inblock.sock,
1723 topt_use_crlf | topt_end_dot | topt_escape_headers |
1724 (tblock->body_only? topt_no_headers : 0) |
1725 (tblock->headers_only? topt_no_body : 0) |
1726 (tblock->return_path_add? topt_add_return_path : 0) |
1727 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1728 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1729 0, /* No size limit */
1730 tblock->add_headers, tblock->remove_headers,
1731 US".", US"..", /* Escaping strings */
1732 tblock->rewrite_rules, tblock->rewrite_existflags,
1733 ob->dkim_private_key, ob->dkim_domain, ob->dkim_selector,
1734 ob->dkim_canon, ob->dkim_strict, ob->dkim_sign_headers
1737 ok = transport_write_message(addrlist, inblock.sock,
1738 topt_use_crlf | topt_end_dot | topt_escape_headers |
1739 (tblock->body_only? topt_no_headers : 0) |
1740 (tblock->headers_only? topt_no_body : 0) |
1741 (tblock->return_path_add? topt_add_return_path : 0) |
1742 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1743 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1744 0, /* No size limit */
1745 tblock->add_headers, tblock->remove_headers,
1746 US".", US"..", /* Escaping strings */
1747 tblock->rewrite_rules, tblock->rewrite_existflags);
1750 /* transport_write_message() uses write() because it is called from other
1751 places to write to non-sockets. This means that under some OS (e.g. Solaris)
1752 it can exit with "Broken pipe" as its error. This really means that the
1753 socket got closed at the far end. */
1755 transport_write_timeout = 0; /* for subsequent transports */
1757 /* Failure can either be some kind of I/O disaster (including timeout),
1758 or the failure of a transport filter or the expansion of added headers. */
1762 buffer[0] = 0; /* There hasn't been a response */
1763 goto RESPONSE_FAILED;
1766 /* We used to send the terminating "." explicitly here, but because of
1767 buffering effects at both ends of TCP/IP connections, you don't gain
1768 anything by keeping it separate, so it might as well go in the final
1769 data buffer for efficiency. This is now done by setting the topt_end_dot
1772 smtp_command = US"end of data";
1774 #ifdef EXPERIMENTAL_PRDR
1775 /* For PRDR we optionally get a partial-responses warning
1776 * followed by the individual responses, before going on with
1777 * the overall response. If we don't get the warning then deal
1778 * with per non-PRDR. */
1781 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '3',
1783 if (!ok && errno == 0)
1786 case '2': prdr_active = FALSE;
1789 case '4': errno = ERRNO_DATA4XX;
1790 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1797 /* For non-PRDR SMTP, we now read a single response that applies to the
1798 whole message. If it is OK, then all the addresses have been delivered. */
1802 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1804 if (!ok && errno == 0 && buffer[0] == '4')
1806 errno = ERRNO_DATA4XX;
1807 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1811 /* For LMTP, we get back a response for every RCPT command that we sent;
1812 some may be accepted and some rejected. For those that get a response, their
1813 status is fixed; any that are accepted have been handed over, even if later
1814 responses crash - at least, that's how I read RFC 2033.
1816 If all went well, mark the recipient addresses as completed, record which
1817 host/IPaddress they were delivered to, and cut out RSET when sending another
1818 message down the same channel. Write the completed addresses to the journal
1819 now so that they are recorded in case there is a crash of hardware or
1820 software before the spool gets updated. Also record the final SMTP
1821 confirmation if needed (for SMTP only). */
1826 int delivery_time = (int)(time(NULL) - start_delivery_time);
1829 uschar *conf = NULL;
1832 /* Make a copy of the host if it is local to this invocation
1833 of the transport. */
1837 thost = store_get(sizeof(host_item));
1839 thost->name = string_copy(host->name);
1840 thost->address = string_copy(host->address);
1844 /* Set up confirmation if needed - applies only to SMTP */
1846 if ((log_extra_selector & LX_smtp_confirmation) != 0 && !lmtp)
1848 uschar *s = string_printing(buffer);
1849 conf = (s == buffer)? (uschar *)string_copy(s) : s;
1852 /* Process all transported addresses - for LMTP or PRDR, read a status for
1855 for (addr = addrlist; addr != first_addr; addr = addr->next)
1857 if (addr->transport_return != PENDING_OK) continue;
1859 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
1860 remaining addresses. Otherwise, it's a return code for just the one
1861 address. For temporary errors, add a retry item for the address so that
1862 it doesn't get tried again too soon. */
1864 #ifdef EXPERIMENTAL_PRDR
1865 if (lmtp || prdr_active)
1870 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1873 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
1874 addr->message = string_sprintf(
1875 #ifdef EXPERIMENTAL_PRDR
1876 "%s error after %s: %s", prdr_active ? "PRDR":"LMTP",
1878 "LMTP error after %s: %s",
1880 big_buffer, string_printing(buffer));
1881 setflag(addr, af_pass_message); /* Allow message to go to user */
1882 if (buffer[0] == '5')
1883 addr->transport_return = FAIL;
1886 errno = ERRNO_DATA4XX;
1887 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1888 addr->transport_return = DEFER;
1889 #ifdef EXPERIMENTAL_PRDR
1892 retry_add_item(addr, addr->address_retry_key, 0);
1896 completed_address = TRUE; /* NOW we can set this flag */
1897 if ((log_extra_selector & LX_smtp_confirmation) != 0)
1899 uschar *s = string_printing(buffer);
1900 conf = (s == buffer)? (uschar *)string_copy(s) : s;
1904 /* SMTP, or success return from LMTP for this address. Pass back the
1905 actual host that was used. */
1907 addr->transport_return = OK;
1908 addr->more_errno = delivery_time;
1909 addr->host_used = thost;
1910 addr->special_action = flag;
1911 addr->message = conf;
1912 #ifdef EXPERIMENTAL_PRDR
1913 if (prdr_active) addr->flags |= af_prdr_used;
1917 #ifdef EXPERIMENTAL_PRDR
1921 /* Update the journal. For homonymic addresses, use the base address plus
1922 the transport name. See lots of comments in deliver.c about the reasons
1923 for the complications when homonyms are involved. Just carry on after
1924 write error, as it may prove possible to update the spool file later. */
1926 if (testflag(addr, af_homonym))
1927 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
1929 sprintf(CS buffer, "%.500s\n", addr->unique);
1931 DEBUG(D_deliver) debug_printf("journalling %s", buffer);
1932 len = Ustrlen(CS buffer);
1933 if (write(journal_fd, buffer, len) != len)
1934 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
1935 "%s: %s", buffer, strerror(errno));
1939 #ifdef EXPERIMENTAL_PRDR
1942 /* PRDR - get the final, overall response. For any non-success
1943 upgrade all the address statuses. */
1944 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1948 if(errno == 0 && buffer[0] == '4')
1950 errno = ERRNO_DATA4XX;
1951 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1953 for (addr = addrlist; addr != first_addr; addr = addr->next)
1954 if (buffer[0] == '5' || addr->transport_return == OK)
1955 addr->transport_return = PENDING_OK; /* allow set_errno action */
1956 goto RESPONSE_FAILED;
1959 /* Update the journal, or setup retry. */
1960 for (addr = addrlist; addr != first_addr; addr = addr->next)
1961 if (addr->transport_return == OK)
1963 if (testflag(addr, af_homonym))
1964 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
1966 sprintf(CS buffer, "%.500s\n", addr->unique);
1968 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s", buffer);
1969 len = Ustrlen(CS buffer);
1970 if (write(journal_fd, buffer, len) != len)
1971 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
1972 "%s: %s", buffer, strerror(errno));
1974 else if (addr->transport_return == DEFER)
1975 retry_add_item(addr, addr->address_retry_key, -2);
1979 /* Ensure the journal file is pushed out to disk. */
1981 if (EXIMfsync(journal_fd) < 0)
1982 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
1988 /* Handle general (not specific to one address) failures here. The value of ok
1989 is used to skip over this code on the falling through case. A timeout causes a
1990 deferral. Other errors may defer or fail according to the response code, and
1991 may set up a special errno value, e.g. after connection chopped, which is
1992 assumed if errno == 0 and there is no text in the buffer. If control reaches
1993 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
1994 the problem is not related to this specific message. */
2003 send_quit = check_response(host, &save_errno, addrlist->more_errno,
2004 buffer, &code, &message, &pass_message);
2010 message = US string_sprintf("send() to %s [%s] failed: %s",
2011 host->name, host->address, strerror(save_errno));
2015 /* This label is jumped to directly when a TLS negotiation has failed,
2016 or was not done for a host for which it is required. Values will be set
2017 in message and save_errno, and setting_up will always be true. Treat as
2018 a temporary error. */
2025 /* If the failure happened while setting up the call, see if the failure was
2026 a 5xx response (this will either be on connection, or following HELO - a 5xx
2027 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
2028 never going to accept them. For other errors during setting up (timeouts or
2029 whatever), defer all addresses, and yield DEFER, so that the host is not
2030 tried again for a while. */
2033 ok = FALSE; /* For when reached by GOTO */
2039 set_errno(addrlist, save_errno, message, FAIL, pass_message);
2043 set_errno(addrlist, save_errno, message, DEFER, pass_message);
2048 /* We want to handle timeouts after MAIL or "." and loss of connection after
2049 "." specially. They can indicate a problem with the sender address or with
2050 the contents of the message rather than a real error on the connection. These
2051 cases are treated in the same way as a 4xx response. This next bit of code
2052 does the classification. */
2063 message_error = TRUE;
2067 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
2068 Ustrncmp(smtp_command,"end ",4) == 0;
2071 case ERRNO_SMTPCLOSED:
2072 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
2076 message_error = FALSE;
2080 /* Handle the cases that are treated as message errors. These are:
2082 (a) negative response or timeout after MAIL
2083 (b) negative response after DATA
2084 (c) negative response or timeout or dropped connection after "."
2086 It won't be a negative response or timeout after RCPT, as that is dealt
2087 with separately above. The action in all cases is to set an appropriate
2088 error code for all the addresses, but to leave yield set to OK because the
2089 host itself has not failed. Of course, it might in practice have failed
2090 when we've had a timeout, but if so, we'll discover that at the next
2091 delivery attempt. For a temporary error, set the message_defer flag, and
2092 write to the logs for information if this is not the last host. The error
2093 for the last host will be logged as part of the address's log line. */
2097 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
2098 set_errno(addrlist, save_errno, message, (code == '5')? FAIL : DEFER,
2101 /* If there's an errno, the message contains just the identity of
2104 if (code != '5') /* Anything other than 5 is treated as temporary */
2107 message = US string_sprintf("%s: %s", message, strerror(save_errno));
2108 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
2109 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
2110 *message_defer = TRUE;
2114 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
2115 ".", or some other transportation error. We defer all addresses and yield
2116 DEFER, except for the case of failed add_headers expansion, or a transport
2117 filter failure, when the yield should be ERROR, to stop it trying other
2122 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
2123 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
2124 set_errno(addrlist, save_errno, message, DEFER, pass_message);
2130 /* If all has gone well, send_quit will be set TRUE, implying we can end the
2131 SMTP session tidily. However, if there were too many addresses to send in one
2132 message (indicated by first_addr being non-NULL) we want to carry on with the
2133 rest of them. Also, it is desirable to send more than one message down the SMTP
2134 connection if there are several waiting, provided we haven't already sent so
2135 many as to hit the configured limit. The function transport_check_waiting looks
2136 for a waiting message and returns its id. Then transport_pass_socket tries to
2137 set up a continued delivery by passing the socket on to another process. The
2138 variable send_rset is FALSE if a message has just been successfully transfered.
2140 If we are already sending down a continued channel, there may be further
2141 addresses not yet delivered that are aimed at the same host, but which have not
2142 been passed in this run of the transport. In this case, continue_more will be
2143 true, and all we should do is send RSET if necessary, and return, leaving the
2146 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
2147 do not want to continue with other messages down the same channel, because that
2148 can lead to looping between two or more messages, all with the same,
2149 temporarily failing address(es). [The retry information isn't updated yet, so
2150 new processes keep on trying.] We probably also don't want to try more of this
2151 message's addresses either.
2153 If we have started a TLS session, we have to end it before passing the
2154 connection to a new process. However, not all servers can handle this (Exim
2155 can), so we do not pass such a connection on if the host matches
2156 hosts_nopass_tls. */
2159 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
2160 "yield=%d first_address is %sNULL\n", ok, send_quit, send_rset,
2161 continue_more, yield, (first_addr == NULL)? "":"not ");
2163 if (completed_address && ok && send_quit)
2166 if (first_addr != NULL || continue_more ||
2168 (tls_out.active < 0 ||
2169 verify_check_this_host(&(ob->hosts_nopass_tls), NULL, host->name,
2170 host->address, NULL) != OK)
2172 transport_check_waiting(tblock->name, host->name,
2173 tblock->connection_max_messages, new_message_id, &more)
2181 if (! (ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
2183 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
2184 host->address, strerror(save_errno));
2187 else if (! (ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2188 ob->command_timeout)))
2191 send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
2195 DEBUG(D_transport) debug_printf("%s\n", msg);
2200 /* Either RSET was not needed, or it succeeded */
2204 if (first_addr != NULL) /* More addresses still to be sent */
2205 { /* in this run of the transport */
2206 continue_sequence++; /* Causes * in logging */
2209 if (continue_more) return yield; /* More addresses for another run */
2211 /* Pass the socket to a new Exim process. Before doing so, we must shut
2212 down TLS. Not all MTAs allow for the continuation of the SMTP session
2213 when TLS is shut down. We test for this by sending a new EHLO. If we
2214 don't get a good response, we don't attempt to pass the socket on. */
2217 if (tls_out.active >= 0)
2219 tls_close(FALSE, TRUE);
2223 ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
2224 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2225 ob->command_timeout);
2229 /* If the socket is successfully passed, we musn't send QUIT (or
2230 indeed anything!) from here. */
2232 if (ok && transport_pass_socket(tblock->name, host->name, host->address,
2233 new_message_id, inblock.sock))
2239 /* If RSET failed and there are addresses left, they get deferred. */
2241 else set_errno(first_addr, errno, msg, DEFER, FALSE);
2245 /* End off tidily with QUIT unless the connection has died or the socket has
2246 been passed to another process. There has been discussion on the net about what
2247 to do after sending QUIT. The wording of the RFC suggests that it is necessary
2248 to wait for a response, but on the other hand, there isn't anything one can do
2249 with an error response, other than log it. Exim used to do that. However,
2250 further discussion suggested that it is positively advantageous not to wait for
2251 the response, but to close the session immediately. This is supposed to move
2252 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
2253 load from the server. (Hosts that are both servers and clients may not see much
2254 difference, of course.) Further discussion indicated that this was safe to do
2255 on Unix systems which have decent implementations of TCP/IP that leave the
2256 connection around for a while (TIME_WAIT) after the application has gone away.
2257 This enables the response sent by the server to be properly ACKed rather than
2258 timed out, as can happen on broken TCP/IP implementations on other OS.
2260 This change is being made on 31-Jul-98. After over a year of trouble-free
2261 operation, the old commented-out code was removed on 17-Sep-99. */
2264 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2269 tls_close(FALSE, TRUE);
2272 /* Close the socket, and return the appropriate value, first setting
2273 continue_transport and continue_hostname NULL to prevent any other addresses
2274 that may include the host from trying to re-use a continuation socket. This
2275 works because the NULL setting is passed back to the calling process, and
2276 remote_max_parallel is forced to 1 when delivering over an existing connection,
2278 If all went well and continue_more is set, we shouldn't actually get here if
2279 there are further addresses, as the return above will be taken. However,
2280 writing RSET might have failed, or there may be other addresses whose hosts are
2281 specified in the transports, and therefore not visible at top level, in which
2282 case continue_more won't get set. */
2284 (void)close(inblock.sock);
2285 continue_transport = NULL;
2286 continue_hostname = NULL;
2293 /*************************************************
2294 * Closedown entry point *
2295 *************************************************/
2297 /* This function is called when exim is passed an open smtp channel
2298 from another incarnation, but the message which it has been asked
2299 to deliver no longer exists. The channel is on stdin.
2301 We might do fancy things like looking for another message to send down
2302 the channel, but if the one we sought has gone, it has probably been
2303 delivered by some other process that itself will seek further messages,
2304 so just close down our connection.
2306 Argument: pointer to the transport instance block
2311 smtp_transport_closedown(transport_instance *tblock)
2313 smtp_transport_options_block *ob =
2314 (smtp_transport_options_block *)(tblock->options_block);
2315 smtp_inblock inblock;
2316 smtp_outblock outblock;
2318 uschar inbuffer[4096];
2319 uschar outbuffer[16];
2321 inblock.sock = fileno(stdin);
2322 inblock.buffer = inbuffer;
2323 inblock.buffersize = sizeof(inbuffer);
2324 inblock.ptr = inbuffer;
2325 inblock.ptrend = inbuffer;
2327 outblock.sock = inblock.sock;
2328 outblock.buffersize = sizeof(outbuffer);
2329 outblock.buffer = outbuffer;
2330 outblock.ptr = outbuffer;
2331 outblock.cmd_count = 0;
2332 outblock.authenticating = FALSE;
2334 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2335 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2336 ob->command_timeout);
2337 (void)close(inblock.sock);
2342 /*************************************************
2343 * Prepare addresses for delivery *
2344 *************************************************/
2346 /* This function is called to flush out error settings from previous delivery
2347 attempts to other hosts. It also records whether we got here via an MX record
2348 or not in the more_errno field of the address. We are interested only in
2349 addresses that are still marked DEFER - others may have got delivered to a
2350 previously considered IP address. Set their status to PENDING_DEFER to indicate
2351 which ones are relevant this time.
2354 addrlist the list of addresses
2355 host the host we are delivering to
2357 Returns: the first address for this delivery
2360 static address_item *
2361 prepare_addresses(address_item *addrlist, host_item *host)
2363 address_item *first_addr = NULL;
2365 for (addr = addrlist; addr != NULL; addr = addr->next)
2367 if (addr->transport_return != DEFER) continue;
2368 if (first_addr == NULL) first_addr = addr;
2369 addr->transport_return = PENDING_DEFER;
2370 addr->basic_errno = 0;
2371 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
2372 addr->message = NULL;
2374 addr->cipher = NULL;
2375 addr->peerdn = NULL;
2383 /*************************************************
2384 * Main entry point *
2385 *************************************************/
2387 /* See local README for interface details. As this is a remote transport, it is
2388 given a chain of addresses to be delivered in one connection, if possible. It
2389 always returns TRUE, indicating that each address has its own independent
2390 status set, except if there is a setting up problem, in which case it returns
2394 smtp_transport_entry(
2395 transport_instance *tblock, /* data for this instantiation */
2396 address_item *addrlist) /* addresses we are working on */
2400 int hosts_defer = 0;
2402 int hosts_looked_up = 0;
2403 int hosts_retry = 0;
2404 int hosts_serial = 0;
2405 int hosts_total = 0;
2406 int total_hosts_tried = 0;
2408 BOOL expired = TRUE;
2409 BOOL continuing = continue_hostname != NULL;
2410 uschar *expanded_hosts = NULL;
2412 uschar *tid = string_sprintf("%s transport", tblock->name);
2413 smtp_transport_options_block *ob =
2414 (smtp_transport_options_block *)(tblock->options_block);
2415 host_item *hostlist = addrlist->host_list;
2416 host_item *host = NULL;
2420 debug_printf("%s transport entered\n", tblock->name);
2421 for (addr = addrlist; addr != NULL; addr = addr->next)
2422 debug_printf(" %s\n", addr->address);
2423 if (continuing) debug_printf("already connected to %s [%s]\n",
2424 continue_hostname, continue_host_address);
2427 /* Set the flag requesting that these hosts be added to the waiting
2428 database if the delivery fails temporarily or if we are running with
2429 queue_smtp or a 2-stage queue run. This gets unset for certain
2430 kinds of error, typically those that are specific to the message. */
2432 update_waiting = TRUE;
2434 /* If a host list is not defined for the addresses - they must all have the
2435 same one in order to be passed to a single transport - or if the transport has
2436 a host list with hosts_override set, use the host list supplied with the
2437 transport. It is an error for this not to exist. */
2439 if (hostlist == NULL || (ob->hosts_override && ob->hosts != NULL))
2441 if (ob->hosts == NULL)
2443 addrlist->message = string_sprintf("%s transport called with no hosts set",
2445 addrlist->transport_return = PANIC;
2446 return FALSE; /* Only top address has status */
2449 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
2452 /* If the transport's host list contains no '$' characters, and we are not
2453 randomizing, it is fixed and therefore a chain of hosts can be built once
2454 and for all, and remembered for subsequent use by other calls to this
2455 transport. If, on the other hand, the host list does contain '$', or we are
2456 randomizing its order, we have to rebuild it each time. In the fixed case,
2457 as the hosts string will never be used again, it doesn't matter that we
2458 replace all the : characters with zeros. */
2460 if (ob->hostlist == NULL)
2462 uschar *s = ob->hosts;
2464 if (Ustrchr(s, '$') != NULL)
2466 expanded_hosts = expand_string(s);
2467 if (expanded_hosts == NULL)
2469 addrlist->message = string_sprintf("failed to expand list of hosts "
2470 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
2471 addrlist->transport_return = search_find_defer? DEFER : PANIC;
2472 return FALSE; /* Only top address has status */
2474 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
2475 "\"%s\"\n", s, expanded_hosts);
2479 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
2481 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
2483 /* Check that the expansion yielded something useful. */
2484 if (hostlist == NULL)
2487 string_sprintf("%s transport has empty hosts setting", tblock->name);
2488 addrlist->transport_return = PANIC;
2489 return FALSE; /* Only top address has status */
2492 /* If there was no expansion of hosts, save the host list for
2495 if (expanded_hosts == NULL) ob->hostlist = hostlist;
2498 /* This is not the first time this transport has been run in this delivery;
2499 the host list was built previously. */
2501 else hostlist = ob->hostlist;
2504 /* The host list was supplied with the address. If hosts_randomize is set, we
2505 must sort it into a random order if it did not come from MX records and has not
2506 already been randomized (but don't bother if continuing down an existing
2509 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continuing)
2511 host_item *newlist = NULL;
2512 while (hostlist != NULL)
2514 host_item *h = hostlist;
2515 hostlist = hostlist->next;
2517 h->sort_key = random_number(100);
2519 if (newlist == NULL)
2524 else if (h->sort_key < newlist->sort_key)
2531 host_item *hh = newlist;
2532 while (hh->next != NULL)
2534 if (h->sort_key < hh->next->sort_key) break;
2542 hostlist = addrlist->host_list = newlist;
2546 /* Sort out the default port. */
2548 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
2551 /* For each host-plus-IP-address on the list:
2553 . If this is a continued delivery and the host isn't the one with the
2554 current connection, skip.
2556 . If the status is unusable (i.e. previously failed or retry checked), skip.
2558 . If no IP address set, get the address, either by turning the name into
2559 an address, calling gethostbyname if gethostbyname is on, or by calling
2560 the DNS. The DNS may yield multiple addresses, in which case insert the
2561 extra ones into the list.
2563 . Get the retry data if not previously obtained for this address and set the
2564 field which remembers the state of this address. Skip if the retry time is
2565 not reached. If not, remember whether retry data was found. The retry string
2566 contains both the name and the IP address.
2568 . Scan the list of addresses and mark those whose status is DEFER as
2569 PENDING_DEFER. These are the only ones that will be processed in this cycle
2572 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
2573 Some addresses may be successfully delivered, others may fail, and yet
2574 others may get temporary errors and so get marked DEFER.
2576 . The return from the delivery attempt is OK if a connection was made and a
2577 valid SMTP dialogue was completed. Otherwise it is DEFER.
2579 . If OK, add a "remove" retry item for this host/IPaddress, if any.
2581 . If fail to connect, or other defer state, add a retry item.
2583 . If there are any addresses whose status is still DEFER, carry on to the
2584 next host/IPaddress, unless we have tried the number of hosts given
2585 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
2586 there is some fancy logic for hosts_max_try that means its limit can be
2587 overstepped in some circumstances.
2589 If we get to the end of the list, all hosts have deferred at least one address,
2590 or not reached their retry times. If delay_after_cutoff is unset, it requests a
2591 delivery attempt to those hosts whose last try was before the arrival time of
2592 the current message. To cope with this, we have to go round the loop a second
2593 time. After that, set the status and error data for any addresses that haven't
2594 had it set already. */
2596 for (cutoff_retry = 0; expired &&
2597 cutoff_retry < ((ob->delay_after_cutoff)? 1 : 2);
2600 host_item *nexthost = NULL;
2601 int unexpired_hosts_tried = 0;
2603 for (host = hostlist;
2605 unexpired_hosts_tried < ob->hosts_max_try &&
2606 total_hosts_tried < ob->hosts_max_try_hardlimit;
2612 BOOL serialized = FALSE;
2613 BOOL host_is_expired = FALSE;
2614 BOOL message_defer = FALSE;
2615 BOOL ifchanges = FALSE;
2616 BOOL some_deferred = FALSE;
2617 address_item *first_addr = NULL;
2618 uschar *interface = NULL;
2619 uschar *retry_host_key = NULL;
2620 uschar *retry_message_key = NULL;
2621 uschar *serialize_key = NULL;
2623 /* Default next host is next host. :-) But this can vary if the
2624 hosts_max_try limit is hit (see below). It may also be reset if a host
2625 address is looked up here (in case the host was multihomed). */
2627 nexthost = host->next;
2629 /* If the address hasn't yet been obtained from the host name, look it up
2630 now, unless the host is already marked as unusable. If it is marked as
2631 unusable, it means that the router was unable to find its IP address (in
2632 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
2633 the lookup failed last time. We don't get this far if *all* MX records
2634 point to non-existent hosts; that is treated as a hard error.
2636 We can just skip this host entirely. When the hosts came from the router,
2637 the address will timeout based on the other host(s); when the address is
2638 looked up below, there is an explicit retry record added.
2640 Note that we mustn't skip unusable hosts if the address is not unset; they
2641 may be needed as expired hosts on the 2nd time round the cutoff loop. */
2643 if (host->address == NULL)
2645 int new_port, flags;
2647 uschar *canonical_name;
2649 if (host->status >= hstatus_unusable)
2651 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
2656 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
2658 /* The host name is permitted to have an attached port. Find it, and
2659 strip it from the name. Just remember it for now. */
2661 new_port = host_item_get_port(host);
2663 /* Count hosts looked up */
2667 /* Find by name if so configured, or if it's an IP address. We don't
2668 just copy the IP address, because we need the test-for-local to happen. */
2670 flags = HOST_FIND_BY_A;
2671 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
2672 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
2674 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
2675 rc = host_find_byname(host, NULL, flags, &canonical_name, TRUE);
2677 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
2678 &canonical_name, NULL);
2680 /* Update the host (and any additional blocks, resulting from
2681 multihoming) with a host-specific port, if any. */
2683 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
2685 /* Failure to find the host at this time (usually DNS temporary failure)
2686 is really a kind of routing failure rather than a transport failure.
2687 Therefore we add a retry item of the routing kind, not to stop us trying
2688 to look this name up here again, but to ensure the address gets timed
2689 out if the failures go on long enough. A complete failure at this point
2690 commonly points to a configuration error, but the best action is still
2691 to carry on for the next host. */
2693 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
2695 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
2697 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
2698 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
2699 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
2700 host->status = hstatus_unusable;
2702 for (addr = addrlist; addr != NULL; addr = addr->next)
2704 if (addr->transport_return != DEFER) continue;
2705 addr->basic_errno = ERRNO_UNKNOWNHOST;
2707 string_sprintf("failed to lookup IP address for %s", host->name);
2712 /* If the host is actually the local host, we may have a problem, or
2713 there may be some cunning configuration going on. In the problem case,
2714 log things and give up. The default transport status is already DEFER. */
2716 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
2718 for (addr = addrlist; addr != NULL; addr = addr->next)
2720 addr->basic_errno = 0;
2721 addr->message = string_sprintf("%s transport found host %s to be "
2722 "local", tblock->name, host->name);
2726 } /* End of block for IP address lookup */
2728 /* If this is a continued delivery, we are interested only in the host
2729 which matches the name of the existing open channel. The check is put
2730 here after the local host lookup, in case the name gets expanded as a
2731 result of the lookup. Set expired FALSE, to save the outer loop executing
2734 if (continuing && (Ustrcmp(continue_hostname, host->name) != 0 ||
2735 Ustrcmp(continue_host_address, host->address) != 0))
2738 continue; /* With next host */
2741 /* Reset the default next host in case a multihomed host whose addresses
2742 are not looked up till just above added to the host list. */
2744 nexthost = host->next;
2746 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
2747 domain is in queue_smtp_domains, we don't actually want to attempt any
2748 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
2749 there is a lookup defer in queue_smtp_domains, proceed as if the domain
2750 were not in it. We don't want to hold up all SMTP deliveries! Except when
2751 doing a two-stage queue run, don't do this if forcing. */
2753 if ((!deliver_force || queue_2stage) && (queue_smtp ||
2754 match_isinlist(addrlist->domain, &queue_smtp_domains, 0,
2755 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
2758 for (addr = addrlist; addr != NULL; addr = addr->next)
2760 if (addr->transport_return != DEFER) continue;
2761 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
2763 continue; /* With next host */
2766 /* Count hosts being considered - purely for an intelligent comment
2767 if none are usable. */
2771 /* Set $host and $host address now in case they are needed for the
2772 interface expansion or the serialize_hosts check; they remain set if an
2773 actual delivery happens. */
2775 deliver_host = host->name;
2776 deliver_host_address = host->address;
2778 /* Set up a string for adding to the retry key if the port number is not
2779 the standard SMTP port. A host may have its own port setting that overrides
2782 pistring = string_sprintf(":%d", (host->port == PORT_NONE)?
2784 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
2786 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
2787 string changes upon expansion, we must add it to the key that is used for
2788 retries, because connections to the same host from a different interface
2789 should be treated separately. */
2791 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET : AF_INET6;
2792 if (!smtp_get_interface(ob->interface, host_af, addrlist, &ifchanges,
2795 if (ifchanges) pistring = string_sprintf("%s/%s", pistring, interface);
2797 /* The first time round the outer loop, check the status of the host by
2798 inspecting the retry data. The second time round, we are interested only
2799 in expired hosts that haven't been tried since this message arrived. */
2801 if (cutoff_retry == 0)
2803 /* Ensure the status of the address is set by checking retry data if
2804 necessary. There maybe host-specific retry data (applicable to all
2805 messages) and also data for retries of a specific message at this host.
2806 If either of these retry records are actually read, the keys used are
2807 returned to save recomputing them later. */
2809 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
2810 ob->retry_include_ip_address, &retry_host_key, &retry_message_key);
2812 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
2813 (host->address == NULL)? US"" : host->address, pistring,
2814 (host->status == hstatus_usable)? "usable" :
2815 (host->status == hstatus_unusable)? "unusable" :
2816 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
2818 /* Skip this address if not usable at this time, noting if it wasn't
2819 actually expired, both locally and in the address. */
2821 switch (host->status)
2823 case hstatus_unusable:
2825 setflag(addrlist, af_retry_skipped);
2828 case hstatus_unusable_expired:
2831 case hwhy_retry: hosts_retry++; break;
2832 case hwhy_failed: hosts_fail++; break;
2833 case hwhy_deferred: hosts_defer++; break;
2836 /* If there was a retry message key, implying that previously there
2837 was a message-specific defer, we don't want to update the list of
2838 messages waiting for these hosts. */
2840 if (retry_message_key != NULL) update_waiting = FALSE;
2841 continue; /* With the next host or IP address */
2845 /* Second time round the loop: if the address is set but expired, and
2846 the message is newer than the last try, let it through. */
2850 if (host->address == NULL ||
2851 host->status != hstatus_unusable_expired ||
2852 host->last_try > received_time)
2855 debug_printf("trying expired host %s [%s]%s\n",
2856 host->name, host->address, pistring);
2857 host_is_expired = TRUE;
2860 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
2861 it remains TRUE only if all hosts are expired and none are actually tried.
2866 /* If this host is listed as one to which access must be serialized,
2867 see if another Exim process has a connection to it, and if so, skip
2868 this host. If not, update the database to record our connection to it
2869 and remember this for later deletion. Do not do any of this if we are
2870 sending the message down a pre-existing connection. */
2873 verify_check_this_host(&(ob->serialize_hosts), NULL, host->name,
2874 host->address, NULL) == OK)
2876 serialize_key = string_sprintf("host-serialize-%s", host->name);
2877 if (!enq_start(serialize_key))
2880 debug_printf("skipping host %s because another Exim process "
2881 "is connected to it\n", host->name);
2888 /* OK, we have an IP address that is not waiting for its retry time to
2889 arrive (it might be expired) OR (second time round the loop) we have an
2890 expired host that hasn't been tried since the message arrived. Have a go
2891 at delivering the message to it. First prepare the addresses by flushing
2892 out the result of previous attempts, and finding the first address that
2893 is still to be delivered. */
2895 first_addr = prepare_addresses(addrlist, host);
2897 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
2898 message_id, host->name, host->address, addrlist->address,
2899 (addrlist->next == NULL)? "" : ", ...");
2901 set_process_info("delivering %s to %s [%s] (%s%s)",
2902 message_id, host->name, host->address, addrlist->address,
2903 (addrlist->next == NULL)? "" : ", ...");
2905 /* This is not for real; don't do the delivery. If there are
2906 any remaining hosts, list them. */
2911 set_errno(addrlist, 0, NULL, OK, FALSE);
2912 for (addr = addrlist; addr != NULL; addr = addr->next)
2914 addr->host_used = host;
2915 addr->special_action = '*';
2916 addr->message = US"delivery bypassed by -N option";
2920 debug_printf("*** delivery by %s transport bypassed by -N option\n"
2921 "*** host and remaining hosts:\n", tblock->name);
2922 for (host2 = host; host2 != NULL; host2 = host2->next)
2923 debug_printf(" %s [%s]\n", host2->name,
2924 (host2->address == NULL)? US"unset" : host2->address);
2929 /* This is for real. If the host is expired, we don't count it for
2930 hosts_max_retry. This ensures that all hosts must expire before an address
2931 is timed out, unless hosts_max_try_hardlimit (which protects against
2932 lunatic DNS configurations) is reached.
2934 If the host is not expired and we are about to hit the hosts_max_retry
2935 limit, check to see if there is a subsequent hosts with a different MX
2936 value. If so, make that the next host, and don't count this one. This is a
2937 heuristic to make sure that different MXs do get tried. With a normal kind
2938 of retry rule, they would get tried anyway when the earlier hosts were
2939 delayed, but if the domain has a "retry every time" type of rule - as is
2940 often used for the the very large ISPs, that won't happen. */
2944 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
2948 debug_printf("hosts_max_try limit reached with this host\n");
2949 for (h = host; h != NULL; h = h->next)
2950 if (h->mx != host->mx) break;
2954 unexpired_hosts_tried--;
2955 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
2956 "and will be tried\n");
2960 /* Attempt the delivery. */
2962 total_hosts_tried++;
2963 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
2964 expanded_hosts != NULL, &message_defer, FALSE);
2967 OK => connection made, each address contains its result;
2968 message_defer is set for message-specific defers (when all
2969 recipients are marked defer)
2970 DEFER => there was a non-message-specific delivery problem;
2971 ERROR => there was a problem setting up the arguments for a filter,
2972 or there was a problem with expanding added headers
2975 /* If the result is not OK, there was a non-message-specific problem.
2976 If the result is DEFER, we need to write to the logs saying what happened
2977 for this particular host, except in the case of authentication and TLS
2978 failures, where the log has already been written. If all hosts defer a
2979 general message is written at the end. */
2981 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL &&
2982 first_addr->basic_errno != ERRNO_TLSFAILURE)
2983 write_logs(first_addr, host);
2985 /* If STARTTLS was accepted, but there was a failure in setting up the
2986 TLS session (usually a certificate screwup), and the host is not in
2987 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
2988 TLS forcibly turned off. We have to start from scratch with a new SMTP
2989 connection. That's why the retry is done from here, not from within
2990 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
2991 session, so the in-clear transmission after those errors, if permitted,
2992 happens inside smtp_deliver().] */
2995 if (rc == DEFER && first_addr->basic_errno == ERRNO_TLSFAILURE &&
2996 ob->tls_tempfail_tryclear &&
2997 verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
2998 host->address, NULL) != OK)
3000 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
3001 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
3002 first_addr = prepare_addresses(addrlist, host);
3003 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
3004 expanded_hosts != NULL, &message_defer, TRUE);
3005 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
3006 write_logs(first_addr, host);
3011 /* Delivery attempt finished */
3013 rs = (rc == OK)? US"OK" : (rc == DEFER)? US"DEFER" : (rc == ERROR)?
3016 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
3017 message_id, host->name, host->address, addrlist->address,
3018 (addrlist->next == NULL)? "" : " (& others)", rs);
3020 /* Release serialization if set up */
3022 if (serialized) enq_end(serialize_key);
3024 /* If the result is DEFER, or if a host retry record is known to exist, we
3025 need to add an item to the retry chain for updating the retry database
3026 at the end of delivery. We only need to add the item to the top address,
3027 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
3028 for any other delivery attempts using the same address. (It is copied into
3029 the unusable tree at the outer level, so even if different address blocks
3030 contain the same address, it still won't get tried again.) */
3032 if (rc == DEFER || retry_host_key != NULL)
3034 int delete_flag = (rc != DEFER)? rf_delete : 0;
3035 if (retry_host_key == NULL)
3037 retry_host_key = ob->retry_include_ip_address?
3038 string_sprintf("T:%S:%s%s", host->name, host->address, pistring) :
3039 string_sprintf("T:%S%s", host->name, pistring);
3042 /* If a delivery of another message over an existing SMTP connection
3043 yields DEFER, we do NOT set up retry data for the host. This covers the
3044 case when there are delays in routing the addresses in the second message
3045 that are so long that the server times out. This is alleviated by not
3046 routing addresses that previously had routing defers when handling an
3047 existing connection, but even so, this case may occur (e.g. if a
3048 previously happily routed address starts giving routing defers). If the
3049 host is genuinely down, another non-continued message delivery will
3050 notice it soon enough. */
3052 if (delete_flag != 0 || !continuing)
3053 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
3055 /* We may have tried an expired host, if its retry time has come; ensure
3056 the status reflects the expiry for the benefit of any other addresses. */
3060 host->status = (host_is_expired)?
3061 hstatus_unusable_expired : hstatus_unusable;
3062 host->why = hwhy_deferred;
3066 /* If message_defer is set (host was OK, but every recipient got deferred
3067 because of some message-specific problem), or if that had happened
3068 previously so that a message retry key exists, add an appropriate item
3069 to the retry chain. Note that if there was a message defer but now there is
3070 a host defer, the message defer record gets deleted. That seems perfectly
3071 reasonable. Also, stop the message from being remembered as waiting
3072 for specific hosts. */
3074 if (message_defer || retry_message_key != NULL)
3076 int delete_flag = message_defer? 0 : rf_delete;
3077 if (retry_message_key == NULL)
3079 retry_message_key = ob->retry_include_ip_address?
3080 string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
3082 string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
3084 retry_add_item(addrlist, retry_message_key,
3085 rf_message | rf_host | delete_flag);
3086 update_waiting = FALSE;
3089 /* Any return other than DEFER (that is, OK or ERROR) means that the
3090 addresses have got their final statuses filled in for this host. In the OK
3091 case, see if any of them are deferred. */
3095 for (addr = addrlist; addr != NULL; addr = addr->next)
3097 if (addr->transport_return == DEFER)
3099 some_deferred = TRUE;
3105 /* If no addresses deferred or the result was ERROR, return. We do this for
3106 ERROR because a failing filter set-up or add_headers expansion is likely to
3107 fail for any host we try. */
3109 if (rc == ERROR || (rc == OK && !some_deferred))
3111 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3112 return TRUE; /* Each address has its status */
3115 /* If the result was DEFER or some individual addresses deferred, let
3116 the loop run to try other hosts with the deferred addresses, except for the
3117 case when we were trying to deliver down an existing channel and failed.
3118 Don't try any other hosts in this case. */
3120 if (continuing) break;
3122 /* If the whole delivery, or some individual addresses, were deferred and
3123 there are more hosts that could be tried, do not count this host towards
3124 the hosts_max_try limit if the age of the message is greater than the
3125 maximum retry time for this host. This means we may try try all hosts,
3126 ignoring the limit, when messages have been around for some time. This is
3127 important because if we don't try all hosts, the address will never time
3128 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
3130 if ((rc == DEFER || some_deferred) && nexthost != NULL)
3133 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
3135 if (retry != NULL && retry->rules != NULL)
3137 retry_rule *last_rule;
3138 for (last_rule = retry->rules;
3139 last_rule->next != NULL;
3140 last_rule = last_rule->next);
3141 timedout = time(NULL) - received_time > last_rule->timeout;
3143 else timedout = TRUE; /* No rule => timed out */
3147 unexpired_hosts_tried--;
3148 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
3149 "hosts_max_try (message older than host's retry time)\n");
3152 } /* End of loop for trying multiple hosts. */
3154 /* This is the end of the loop that repeats iff expired is TRUE and
3155 ob->delay_after_cutoff is FALSE. The second time round we will
3156 try those hosts that haven't been tried since the message arrived. */
3160 debug_printf("all IP addresses skipped or deferred at least one address\n");
3161 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
3162 debug_printf("retrying IP addresses not tried since message arrived\n");
3167 /* Get here if all IP addresses are skipped or defer at least one address. In
3168 MUA wrapper mode, this will happen only for connection or other non-message-
3169 specific failures. Force the delivery status for all addresses to FAIL. */
3173 for (addr = addrlist; addr != NULL; addr = addr->next)
3174 addr->transport_return = FAIL;
3178 /* In the normal, non-wrapper case, add a standard message to each deferred
3179 address if there hasn't been an error, that is, if it hasn't actually been
3180 tried this time. The variable "expired" will be FALSE if any deliveries were
3181 actually tried, or if there was at least one host that was not expired. That
3182 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
3183 a delivery has been tried, an error code will be set, and the failing of the
3184 message is handled by the retry code later.
3186 If queue_smtp is set, or this transport was called to send a subsequent message
3187 down an existing TCP/IP connection, and something caused the host not to be
3188 found, we end up here, but can detect these cases and handle them specially. */
3190 for (addr = addrlist; addr != NULL; addr = addr->next)
3192 /* If host is not NULL, it means that we stopped processing the host list
3193 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
3194 means we need to behave as if some hosts were skipped because their retry
3195 time had not come. Specifically, this prevents the address from timing out.
3196 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
3197 hosts were tried. */
3201 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
3204 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
3205 "hosts were tried\n");
3210 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
3211 setflag(addr, af_retry_skipped);
3215 if (queue_smtp) /* no deliveries attempted */
3217 addr->transport_return = DEFER;
3218 addr->basic_errno = 0;
3219 addr->message = US"SMTP delivery explicitly queued";
3222 else if (addr->transport_return == DEFER &&
3223 (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0) &&
3224 addr->message == NULL)
3226 addr->basic_errno = ERRNO_HRETRY;
3227 if (continue_hostname != NULL)
3229 addr->message = US"no host found for existing SMTP connection";
3233 setflag(addr, af_pass_message); /* This is not a security risk */
3234 addr->message = (ob->delay_after_cutoff)?
3235 US"retry time not reached for any host after a long failure period" :
3236 US"all hosts have been failing for a long time and were last tried "
3237 "after this message arrived";
3239 /* If we are already using fallback hosts, or there are no fallback hosts
3240 defined, convert the result to FAIL to cause a bounce. */
3242 if (addr->host_list == addr->fallback_hosts ||
3243 addr->fallback_hosts == NULL)
3244 addr->transport_return = FAIL;
3248 if (hosts_retry == hosts_total)
3249 addr->message = US"retry time not reached for any host";
3250 else if (hosts_fail == hosts_total)
3251 addr->message = US"all host address lookups failed permanently";
3252 else if (hosts_defer == hosts_total)
3253 addr->message = US"all host address lookups failed temporarily";
3254 else if (hosts_serial == hosts_total)
3255 addr->message = US"connection limit reached for all hosts";
3256 else if (hosts_fail+hosts_defer == hosts_total)
3257 addr->message = US"all host address lookups failed";
3258 else addr->message = US"some host address lookups failed and retry time "
3259 "not reached for other hosts or connection limit reached";
3264 /* Update the database which keeps information about which messages are waiting
3265 for which hosts to become available. For some message-specific errors, the
3266 update_waiting flag is turned off because we don't want follow-on deliveries in
3267 those cases. If this transport instance is explicitly limited to one message
3268 per connection then follow-on deliveries are not possible and there's no need
3269 to create/update the per-transport wait-<transport_name> database. */
3271 if (update_waiting && tblock->connection_max_messages != 1)
3272 transport_update_waiting(hostlist, tblock->name);
3276 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3278 return TRUE; /* Each address has its status */
3281 /* End of transport/smtp.c */