1 /* $Cambridge: exim/src/src/transports/smtp.c,v 1.44 2009/11/16 19:56:54 nm4 Exp $ */
3 /*************************************************
4 * Exim - an Internet mail transport agent *
5 *************************************************/
7 /* Copyright (c) University of Cambridge 1995 - 2009 */
8 /* See the file NOTICE for conditions of use and distribution. */
14 #define PENDING_DEFER (PENDING + DEFER)
15 #define PENDING_OK (PENDING + OK)
18 /* Options specific to the smtp transport. This transport also supports LMTP
19 over TCP/IP. The options must be in alphabetic order (note that "_" comes
20 before the lower case letters). Some live in the transport_instance block so as
21 to be publicly visible; these are flagged with opt_public. */
23 optionlist smtp_transport_options[] = {
24 { "address_retry_include_sender", opt_bool,
25 (void *)offsetof(smtp_transport_options_block, address_retry_include_sender) },
26 { "allow_localhost", opt_bool,
27 (void *)offsetof(smtp_transport_options_block, allow_localhost) },
28 { "authenticated_sender", opt_stringptr,
29 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
30 { "authenticated_sender_force", opt_bool,
31 (void *)offsetof(smtp_transport_options_block, authenticated_sender_force) },
32 { "command_timeout", opt_time,
33 (void *)offsetof(smtp_transport_options_block, command_timeout) },
34 { "connect_timeout", opt_time,
35 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
36 { "connection_max_messages", opt_int | opt_public,
37 (void *)offsetof(transport_instance, connection_max_messages) },
38 { "data_timeout", opt_time,
39 (void *)offsetof(smtp_transport_options_block, data_timeout) },
40 { "delay_after_cutoff", opt_bool,
41 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
43 { "dkim_canon", opt_stringptr,
44 (void *)offsetof(smtp_transport_options_block, dkim_canon) },
45 { "dkim_domain", opt_stringptr,
46 (void *)offsetof(smtp_transport_options_block, dkim_domain) },
47 { "dkim_private_key", opt_stringptr,
48 (void *)offsetof(smtp_transport_options_block, dkim_private_key) },
49 { "dkim_selector", opt_stringptr,
50 (void *)offsetof(smtp_transport_options_block, dkim_selector) },
51 { "dkim_sign_headers", opt_stringptr,
52 (void *)offsetof(smtp_transport_options_block, dkim_sign_headers) },
53 { "dkim_strict", opt_stringptr,
54 (void *)offsetof(smtp_transport_options_block, dkim_strict) },
56 { "dns_qualify_single", opt_bool,
57 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
58 { "dns_search_parents", opt_bool,
59 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
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 { "gnutls_require_kx", opt_stringptr,
68 (void *)offsetof(smtp_transport_options_block, gnutls_require_kx) },
69 { "gnutls_require_mac", opt_stringptr,
70 (void *)offsetof(smtp_transport_options_block, gnutls_require_mac) },
71 { "gnutls_require_protocols", opt_stringptr,
72 (void *)offsetof(smtp_transport_options_block, gnutls_require_proto) },
74 { "helo_data", opt_stringptr,
75 (void *)offsetof(smtp_transport_options_block, helo_data) },
76 { "hosts", opt_stringptr,
77 (void *)offsetof(smtp_transport_options_block, hosts) },
78 { "hosts_avoid_esmtp", opt_stringptr,
79 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
80 { "hosts_avoid_pipelining", opt_stringptr,
81 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
83 { "hosts_avoid_tls", opt_stringptr,
84 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
86 { "hosts_max_try", opt_int,
87 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
88 { "hosts_max_try_hardlimit", opt_int,
89 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
91 { "hosts_nopass_tls", opt_stringptr,
92 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
94 { "hosts_override", opt_bool,
95 (void *)offsetof(smtp_transport_options_block, hosts_override) },
96 { "hosts_randomize", opt_bool,
97 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
98 { "hosts_require_auth", opt_stringptr,
99 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
101 { "hosts_require_tls", opt_stringptr,
102 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
104 { "hosts_try_auth", opt_stringptr,
105 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
106 { "interface", opt_stringptr,
107 (void *)offsetof(smtp_transport_options_block, interface) },
108 { "keepalive", opt_bool,
109 (void *)offsetof(smtp_transport_options_block, keepalive) },
110 { "lmtp_ignore_quota", opt_bool,
111 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
112 { "max_rcpt", opt_int | opt_public,
113 (void *)offsetof(transport_instance, max_addresses) },
114 { "multi_domain", opt_bool | opt_public,
115 (void *)offsetof(transport_instance, multi_domain) },
116 { "port", opt_stringptr,
117 (void *)offsetof(smtp_transport_options_block, port) },
118 { "protocol", opt_stringptr,
119 (void *)offsetof(smtp_transport_options_block, protocol) },
120 { "retry_include_ip_address", opt_bool,
121 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
122 { "serialize_hosts", opt_stringptr,
123 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
124 { "size_addition", opt_int,
125 (void *)offsetof(smtp_transport_options_block, size_addition) }
127 ,{ "tls_certificate", opt_stringptr,
128 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
129 { "tls_crl", opt_stringptr,
130 (void *)offsetof(smtp_transport_options_block, tls_crl) },
131 { "tls_privatekey", opt_stringptr,
132 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
133 { "tls_require_ciphers", opt_stringptr,
134 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
135 { "tls_tempfail_tryclear", opt_bool,
136 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
137 { "tls_verify_certificates", opt_stringptr,
138 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) }
142 /* Size of the options list. An extern variable has to be used so that its
143 address can appear in the tables drtables.c. */
145 int smtp_transport_options_count =
146 sizeof(smtp_transport_options)/sizeof(optionlist);
148 /* Default private options block for the smtp transport. */
150 smtp_transport_options_block smtp_transport_option_defaults = {
152 NULL, /* fallback_hosts */
154 NULL, /* fallback_hostlist */
155 NULL, /* authenticated_sender */
156 US"$primary_hostname", /* helo_data */
157 NULL, /* interface */
159 US"smtp", /* protocol */
160 NULL, /* serialize_hosts */
161 NULL, /* hosts_try_auth */
162 NULL, /* hosts_require_auth */
163 NULL, /* hosts_require_tls */
164 NULL, /* hosts_avoid_tls */
165 NULL, /* hosts_avoid_pipelining */
166 NULL, /* hosts_avoid_esmtp */
167 NULL, /* hosts_nopass_tls */
168 5*60, /* command_timeout */
169 5*60, /* connect_timeout; shorter system default overrides */
170 5*60, /* data timeout */
171 10*60, /* final timeout */
172 1024, /* size_addition */
173 5, /* hosts_max_try */
174 50, /* hosts_max_try_hardlimit */
175 TRUE, /* address_retry_include_sender */
176 FALSE, /* allow_localhost */
177 FALSE, /* authenticated_sender_force */
178 FALSE, /* gethostbyname */
179 TRUE, /* dns_qualify_single */
180 FALSE, /* dns_search_parents */
181 TRUE, /* delay_after_cutoff */
182 FALSE, /* hosts_override */
183 FALSE, /* hosts_randomize */
184 TRUE, /* keepalive */
185 FALSE, /* lmtp_ignore_quota */
186 TRUE /* retry_include_ip_address */
188 ,NULL, /* tls_certificate */
190 NULL, /* tls_privatekey */
191 NULL, /* tls_require_ciphers */
192 NULL, /* gnutls_require_kx */
193 NULL, /* gnutls_require_mac */
194 NULL, /* gnutls_require_proto */
195 NULL, /* tls_verify_certificates */
196 TRUE /* tls_tempfail_tryclear */
199 ,NULL, /* dkim_canon */
200 NULL, /* dkim_domain */
201 NULL, /* dkim_private_key */
202 NULL, /* dkim_selector */
203 NULL, /* dkim_sign_headers */
204 NULL /* dkim_strict */
211 static uschar *smtp_command; /* Points to last cmd for error messages */
212 static uschar *mail_command; /* Points to MAIL cmd for error messages */
213 static BOOL update_waiting; /* TRUE to update the "wait" database */
216 /*************************************************
217 * Setup entry point *
218 *************************************************/
220 /* This function is called when the transport is about to be used,
221 but before running it in a sub-process. It is used for two things:
223 (1) To set the fallback host list in addresses, when delivering.
224 (2) To pass back the interface, port, protocol, and other options, for use
225 during callout verification.
228 tblock pointer to the transport instance block
229 addrlist list of addresses about to be transported
230 tf if not NULL, pointer to block in which to return options
231 uid the uid that will be set (not used)
232 gid the gid that will be set (not used)
233 errmsg place for error message (not used)
235 Returns: OK always (FAIL, DEFER not used)
239 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
240 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
242 smtp_transport_options_block *ob =
243 (smtp_transport_options_block *)(tblock->options_block);
245 errmsg = errmsg; /* Keep picky compilers happy */
249 /* Pass back options if required. This interface is getting very messy. */
253 tf->interface = ob->interface;
255 tf->protocol = ob->protocol;
256 tf->hosts = ob->hosts;
257 tf->hosts_override = ob->hosts_override;
258 tf->hosts_randomize = ob->hosts_randomize;
259 tf->gethostbyname = ob->gethostbyname;
260 tf->qualify_single = ob->dns_qualify_single;
261 tf->search_parents = ob->dns_search_parents;
262 tf->helo_data = ob->helo_data;
265 /* Set the fallback host list for all the addresses that don't have fallback
266 host lists, provided that the local host wasn't present in the original host
269 if (!testflag(addrlist, af_local_host_removed))
271 for (; addrlist != NULL; addrlist = addrlist->next)
272 if (addrlist->fallback_hosts == NULL)
273 addrlist->fallback_hosts = ob->fallback_hostlist;
281 /*************************************************
282 * Initialization entry point *
283 *************************************************/
285 /* Called for each instance, after its options have been read, to
286 enable consistency checks to be done, or anything else that needs
289 Argument: pointer to the transport instance block
294 smtp_transport_init(transport_instance *tblock)
296 smtp_transport_options_block *ob =
297 (smtp_transport_options_block *)(tblock->options_block);
299 /* Retry_use_local_part defaults FALSE if unset */
301 if (tblock->retry_use_local_part == TRUE_UNSET)
302 tblock->retry_use_local_part = FALSE;
304 /* Set the default port according to the protocol */
306 if (ob->port == NULL)
307 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" : US"smtp";
309 /* Set up the setup entry point, to be called before subprocesses for this
312 tblock->setup = smtp_transport_setup;
314 /* Complain if any of the timeouts are zero. */
316 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
317 ob->final_timeout <= 0)
318 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
319 "command, data, or final timeout value is zero for %s transport",
322 /* If hosts_override is set and there are local hosts, set the global
323 flag that stops verify from showing router hosts. */
325 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
327 /* If there are any fallback hosts listed, build a chain of host items
328 for them, but do not do any lookups at this time. */
330 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
337 /*************************************************
338 * Set delivery info into all active addresses *
339 *************************************************/
341 /* Only addresses whose status is >= PENDING are relevant. A lesser
342 status means that an address is not currently being processed.
345 addrlist points to a chain of addresses
346 errno_value to put in each address's errno field
347 msg to put in each address's message field
348 rc to put in each address's transport_return field
349 pass_message if TRUE, set the "pass message" flag in the address
351 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
352 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
353 this particular type of timeout.
359 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
364 if (errno_value == ERRNO_CONNECTTIMEOUT)
366 errno_value = ETIMEDOUT;
367 orvalue = RTEF_CTOUT;
369 for (addr = addrlist; addr != NULL; addr = addr->next)
371 if (addr->transport_return < PENDING) continue;
372 addr->basic_errno = errno_value;
373 addr->more_errno |= orvalue;
377 if (pass_message) setflag(addr, af_pass_message);
379 addr->transport_return = rc;
385 /*************************************************
386 * Check an SMTP response *
387 *************************************************/
389 /* This function is given an errno code and the SMTP response buffer
390 to analyse, together with the host identification for generating messages. It
391 sets an appropriate message and puts the first digit of the response code into
392 the yield variable. If no response was actually read, a suitable digit is
396 host the current host, to get its name for messages
397 errno_value pointer to the errno value
398 more_errno from the top address for use with ERRNO_FILTER_FAIL
399 buffer the SMTP response buffer
400 yield where to put a one-digit SMTP response code
401 message where to put an errror message
402 pass_message set TRUE if message is an SMTP response
404 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
407 static BOOL check_response(host_item *host, int *errno_value, int more_errno,
408 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
412 if (smtp_use_pipelining &&
413 (Ustrcmp(smtp_command, "MAIL") == 0 ||
414 Ustrcmp(smtp_command, "RCPT") == 0 ||
415 Ustrcmp(smtp_command, "DATA") == 0))
418 *yield = '4'; /* Default setting is to give a temporary error */
420 /* Handle response timeout */
422 if (*errno_value == ETIMEDOUT)
424 *message = US string_sprintf("SMTP timeout while connected to %s [%s] "
425 "after %s%s", host->name, host->address, pl, smtp_command);
426 if (transport_count > 0)
427 *message = US string_sprintf("%s (%d bytes written)", *message,
432 /* Handle malformed SMTP response */
434 if (*errno_value == ERRNO_SMTPFORMAT)
436 uschar *malfresp = string_printing(buffer);
437 while (isspace(*malfresp)) malfresp++;
439 *message = string_sprintf("Malformed SMTP reply (an empty line) from "
440 "%s [%s] in response to %s%s", host->name, host->address, pl,
443 *message = string_sprintf("Malformed SMTP reply from %s [%s] in response "
444 "to %s%s: %s", host->name, host->address, pl, smtp_command, malfresp);
448 /* Handle a failed filter process error; can't send QUIT as we mustn't
451 if (*errno_value == ERRNO_FILTER_FAIL)
453 *message = US string_sprintf("transport filter process failed (%d)%s",
455 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
459 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
462 if (*errno_value == ERRNO_CHHEADER_FAIL)
465 US string_sprintf("failed to expand headers_add or headers_remove: %s",
466 expand_string_message);
470 /* Handle failure to write a complete data block */
472 if (*errno_value == ERRNO_WRITEINCOMPLETE)
474 *message = US string_sprintf("failed to write a data block");
478 /* Handle error responses from the remote mailer. */
482 uschar *s = string_printing(buffer);
483 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
484 "host %s [%s]: %s", pl, smtp_command, host->name, host->address, s);
485 *pass_message = TRUE;
490 /* No data was read. If there is no errno, this must be the EOF (i.e.
491 connection closed) case, which causes deferral. An explicit connection reset
492 error has the same effect. Otherwise, put the host's identity in the message,
493 leaving the errno value to be interpreted as well. In all cases, we have to
494 assume the connection is now dead. */
496 if (*errno_value == 0 || *errno_value == ECONNRESET)
498 *errno_value = ERRNO_SMTPCLOSED;
499 *message = US string_sprintf("Remote host %s [%s] closed connection "
500 "in response to %s%s", host->name, host->address, pl, smtp_command);
502 else *message = US string_sprintf("%s [%s]", host->name, host->address);
509 /*************************************************
510 * Write error message to logs *
511 *************************************************/
513 /* This writes to the main log and to the message log.
516 addr the address item containing error information
517 host the current host
523 write_logs(address_item *addr, host_item *host)
525 if (addr->message != NULL)
527 uschar *message = addr->message;
528 if (addr->basic_errno > 0)
529 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
530 log_write(0, LOG_MAIN, "%s", message);
531 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
536 ((log_extra_selector & LX_outgoing_port) != 0)?
537 string_sprintf("%s [%s]:%d", host->name, host->address,
538 (host->port == PORT_NONE)? 25 : host->port)
540 string_sprintf("%s [%s]", host->name, host->address);
541 log_write(0, LOG_MAIN, "%s %s", msg, strerror(addr->basic_errno));
542 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), msg,
543 strerror(addr->basic_errno));
549 /*************************************************
550 * Synchronize SMTP responses *
551 *************************************************/
553 /* This function is called from smtp_deliver() to receive SMTP responses from
554 the server, and match them up with the commands to which they relate. When
555 PIPELINING is not in use, this function is called after every command, and is
556 therefore somewhat over-engineered, but it is simpler to use a single scheme
557 that works both with and without PIPELINING instead of having two separate sets
560 The set of commands that are buffered up with pipelining may start with MAIL
561 and may end with DATA; in between are RCPT commands that correspond to the
562 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
563 etc.) are never buffered.
565 Errors after MAIL or DATA abort the whole process leaving the response in the
566 buffer. After MAIL, pending responses are flushed, and the original command is
567 re-instated in big_buffer for error messages. For RCPT commands, the remote is
568 permitted to reject some recipient addresses while accepting others. However
569 certain errors clearly abort the whole process. Set the value in
570 transport_return to PENDING_OK if the address is accepted. If there is a
571 subsequent general error, it will get reset accordingly. If not, it will get
572 converted to OK at the end.
575 addrlist the complete address list
576 include_affixes TRUE if affixes include in RCPT
577 sync_addr ptr to the ptr of the one to start scanning at (updated)
578 host the host we are connected to
579 count the number of responses to read
581 include_sender true if 4xx retry is to include the sender it its key
582 pending_MAIL true if the first response is for MAIL
583 pending_DATA 0 if last command sent was not DATA
584 +1 if previously had a good recipient
585 -1 if not previously had a good recipient
586 inblock incoming SMTP block
587 timeout timeout value
588 buffer buffer for reading response
589 buffsize size of buffer
591 Returns: 3 if at least one address had 2xx and one had 5xx
592 2 if at least one address had 5xx but none had 2xx
593 1 if at least one host had a 2xx response, but none had 5xx
594 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
595 -1 timeout while reading RCPT response
596 -2 I/O or other non-response error for RCPT
597 -3 DATA or MAIL failed - errno and buffer set
601 sync_responses(address_item *addrlist, BOOL include_affixes,
602 address_item **sync_addr, host_item *host, int count,
603 BOOL address_retry_include_sender, BOOL pending_MAIL,
604 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
607 address_item *addr = *sync_addr;
610 /* Handle the response for a MAIL command. On error, reinstate the original
611 command in big_buffer for error message use, and flush any further pending
612 responses before returning, except after I/O errors and timeouts. */
617 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
619 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
620 if (errno == 0 && buffer[0] != 0)
622 uschar flushbuffer[4096];
624 if (buffer[0] == '4')
626 save_errno = ERRNO_MAIL4XX;
627 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
631 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
633 && (errno != 0 || flushbuffer[0] == 0))
642 if (pending_DATA) count--; /* Number of RCPT responses to come */
644 /* Read and handle the required number of RCPT responses, matching each one up
645 with an address by scanning for the next address whose status is PENDING_DEFER.
650 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
652 /* The address was accepted */
654 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
657 addr->transport_return = PENDING_OK;
659 /* If af_dr_retry_exists is set, there was a routing delay on this address;
660 ensure that any address-specific retry record is expunged. We do this both
661 for the basic key and for the version that also includes the sender. */
663 if (testflag(addr, af_dr_retry_exists))
665 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
667 retry_add_item(addr, altkey, rf_delete);
668 retry_add_item(addr, addr->address_retry_key, rf_delete);
672 /* Timeout while reading the response */
674 else if (errno == ETIMEDOUT)
676 int save_errno = errno;
677 uschar *message = string_sprintf("SMTP timeout while connected to %s [%s] "
678 "after RCPT TO:<%s>", host->name, host->address,
679 transport_rcpt_address(addr, include_affixes));
680 set_errno(addrlist, save_errno, message, DEFER, FALSE);
681 retry_add_item(addr, addr->address_retry_key, 0);
682 update_waiting = FALSE;
686 /* Handle other errors in obtaining an SMTP response by returning -1. This
687 will cause all the addresses to be deferred. Restore the SMTP command in
688 big_buffer for which we are checking the response, so the error message
691 else if (errno != 0 || buffer[0] == 0)
693 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
694 transport_rcpt_address(addr, include_affixes));
698 /* Handle SMTP permanent and temporary response codes. */
703 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
704 "host %s [%s]: %s", transport_rcpt_address(addr, include_affixes),
705 host->name, host->address, string_printing(buffer));
706 setflag(addr, af_pass_message);
707 deliver_msglog("%s %s\n", tod_stamp(tod_log), addr->message);
709 /* The response was 5xx */
711 if (buffer[0] == '5')
713 addr->transport_return = FAIL;
717 /* The response was 4xx */
721 addr->transport_return = DEFER;
722 addr->basic_errno = ERRNO_RCPT4XX;
723 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
725 /* Log temporary errors if there are more hosts to be tried. */
727 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", addr->message);
729 /* Do not put this message on the list of those waiting for specific
730 hosts, as otherwise it is likely to be tried too often. */
732 update_waiting = FALSE;
734 /* Add a retry item for the address so that it doesn't get tried again
735 too soon. If address_retry_include_sender is true, add the sender address
738 if (address_retry_include_sender)
740 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
742 retry_add_item(addr, altkey, 0);
744 else retry_add_item(addr, addr->address_retry_key, 0);
747 } /* Loop for next RCPT response */
749 /* Update where to start at for the next block of responses, unless we
750 have already handled all the addresses. */
752 if (addr != NULL) *sync_addr = addr->next;
754 /* Handle a response to DATA. If we have not had any good recipients, either
755 previously or in this block, the response is ignored. */
757 if (pending_DATA != 0 &&
758 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
763 if (pending_DATA > 0 || (yield & 1) != 0)
765 if (errno == 0 && buffer[0] == '4')
767 errno = ERRNO_DATA4XX;
768 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
772 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
773 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
774 "is in use and there were no good recipients\n", msg);
777 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
778 present) received 3xx. If any RCPTs were handled and yielded anything other
779 than 4xx, yield will be set non-zero. */
786 /*************************************************
787 * Deliver address list to given host *
788 *************************************************/
790 /* If continue_hostname is not null, we get here only when continuing to
791 deliver down an existing channel. The channel was passed as the standard
792 input. TLS is never active on a passed channel; the previous process always
793 closes it down before passing the connection on.
795 Otherwise, we have to make a connection to the remote host, and do the
796 initial protocol exchange.
798 When running as an MUA wrapper, if the sender or any recipient is rejected,
799 temporarily or permanently, we force failure for all recipients.
802 addrlist chain of potential addresses to deliver; only those whose
803 transport_return field is set to PENDING_DEFER are currently
804 being processed; others should be skipped - they have either
805 been delivered to an earlier host or IP address, or been
806 failed by one of them.
807 host host to deliver to
808 host_af AF_INET or AF_INET6
809 port default TCP/IP port to use, in host byte order
810 interface interface to bind to, or NULL
811 tblock transport instance block
812 copy_host TRUE if host set in addr->host_used must be copied, because
813 it is specific to this call of the transport
814 message_defer set TRUE if yield is OK, but all addresses were deferred
815 because of a non-recipient, non-host failure, that is, a
816 4xx response to MAIL FROM, DATA, or ".". This is a defer
817 that is specific to the message.
818 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
819 a second attempt after TLS initialization fails
821 Returns: OK - the connection was made and the delivery attempted;
822 the result for each address is in its data block.
823 DEFER - the connection could not be made, or something failed
824 while setting up the SMTP session, or there was a
825 non-message-specific error, such as a timeout.
826 ERROR - a filter command is specified for this transport,
827 and there was a problem setting it up; OR helo_data
828 or add_headers or authenticated_sender is specified
829 for this transport, and the string failed to expand
833 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
834 uschar *interface, transport_instance *tblock, BOOL copy_host,
835 BOOL *message_defer, BOOL suppress_tls)
838 address_item *sync_addr;
839 address_item *first_addr = addrlist;
844 time_t start_delivery_time = time(NULL);
845 smtp_transport_options_block *ob =
846 (smtp_transport_options_block *)(tblock->options_block);
847 BOOL lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
849 BOOL send_rset = TRUE;
850 BOOL send_quit = TRUE;
851 BOOL setting_up = TRUE;
852 BOOL completed_address = FALSE;
855 BOOL pass_message = FALSE;
856 smtp_inblock inblock;
857 smtp_outblock outblock;
858 int max_rcpt = tblock->max_addresses;
859 uschar *igquotstr = US"";
860 uschar *local_authenticated_sender = authenticated_sender;
861 uschar *helo_data = NULL;
862 uschar *message = NULL;
863 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
866 uschar inbuffer[4096];
867 uschar outbuffer[1024];
869 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
871 *message_defer = FALSE;
872 smtp_command = US"initial connection";
873 if (max_rcpt == 0) max_rcpt = 999999;
875 /* Set up the buffer for reading SMTP response packets. */
877 inblock.buffer = inbuffer;
878 inblock.buffersize = sizeof(inbuffer);
879 inblock.ptr = inbuffer;
880 inblock.ptrend = inbuffer;
882 /* Set up the buffer for holding SMTP commands while pipelining */
884 outblock.buffer = outbuffer;
885 outblock.buffersize = sizeof(outbuffer);
886 outblock.ptr = outbuffer;
887 outblock.cmd_count = 0;
888 outblock.authenticating = FALSE;
890 /* Reset the parameters of a TLS session. */
895 /* If an authenticated_sender override has been specified for this transport
896 instance, expand it. If the expansion is forced to fail, and there was already
897 an authenticated_sender for this message, the original value will be used.
898 Other expansion failures are serious. An empty result is ignored, but there is
899 otherwise no check - this feature is expected to be used with LMTP and other
900 cases where non-standard addresses (e.g. without domains) might be required. */
902 if (ob->authenticated_sender != NULL)
904 uschar *new = expand_string(ob->authenticated_sender);
907 if (!expand_string_forcedfail)
909 uschar *message = string_sprintf("failed to expand "
910 "authenticated_sender: %s", expand_string_message);
911 set_errno(addrlist, 0, message, DEFER, FALSE);
915 else if (new[0] != 0) local_authenticated_sender = new;
918 /* Make a connection to the host if this isn't a continued delivery, and handle
919 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
920 specially so they can be identified for retries. */
922 if (continue_hostname == NULL)
924 inblock.sock = outblock.sock =
925 smtp_connect(host, host_af, port, interface, ob->connect_timeout,
926 ob->keepalive); /* This puts port into host->port */
928 if (inblock.sock < 0)
930 set_errno(addrlist, (errno == ETIMEDOUT)? ERRNO_CONNECTTIMEOUT : errno,
935 /* Expand the greeting message while waiting for the initial response. (Makes
936 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
937 delayed till here so that $sending_interface and $sending_port are set. */
939 helo_data = expand_string(ob->helo_data);
941 /* The first thing is to wait for an initial OK response. The dreaded "goto"
942 is nevertheless a reasonably clean way of programming this kind of logic,
943 where you want to escape on any error. */
945 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
946 ob->command_timeout)) goto RESPONSE_FAILED;
948 /* Now check if the helo_data expansion went well, and sign off cleanly if it
951 if (helo_data == NULL)
953 uschar *message = string_sprintf("failed to expand helo_data: %s",
954 expand_string_message);
955 set_errno(addrlist, 0, message, DEFER, FALSE);
960 /** Debugging without sending a message
961 addrlist->transport_return = DEFER;
965 /* Errors that occur after this point follow an SMTP command, which is
966 left in big_buffer by smtp_write_command() for use in error messages. */
968 smtp_command = big_buffer;
970 /* Tell the remote who we are...
972 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
973 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
974 greeting is of this form. The assumption was that the far end supports it
975 properly... but experience shows that there are some that give 5xx responses,
976 even though the banner includes "ESMTP" (there's a bloody-minded one that
977 says "ESMTP not spoken here"). Cope with that case.
979 September 2000: Time has passed, and it seems reasonable now to always send
980 EHLO at the start. It is also convenient to make the change while installing
983 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
984 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
985 would be no way to send out the mails, so there is now a host list
986 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
987 PIPELINING problem as well. Maybe it can also be useful to cure other
988 problems with broken servers.
990 Exim originally sent "Helo" at this point and ran for nearly a year that way.
991 Then somebody tried it with a Microsoft mailer... It seems that all other
992 mailers use upper case for some reason (the RFC is quite clear about case
993 independence) so, for peace of mind, I gave in. */
995 esmtp = verify_check_this_host(&(ob->hosts_avoid_esmtp), NULL,
996 host->name, host->address, NULL) != OK;
1000 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1001 lmtp? "LHLO" : "EHLO", helo_data) < 0)
1003 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1004 ob->command_timeout))
1006 if (errno != 0 || buffer[0] == 0 || lmtp) goto RESPONSE_FAILED;
1013 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1018 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1020 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1021 ob->command_timeout)) goto RESPONSE_FAILED;
1024 /* Set IGNOREQUOTA if the response to LHLO specifies support and the
1025 lmtp_ignore_quota option was set. */
1027 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1028 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1029 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1031 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1034 tls_offered = esmtp &&
1035 pcre_exec(regex_STARTTLS, NULL, CS buffer, Ustrlen(buffer), 0,
1036 PCRE_EOPT, NULL, 0) >= 0;
1040 /* For continuing deliveries down the same channel, the socket is the standard
1041 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1042 below). Set up the pointer to where subsequent commands will be left, for
1043 error messages. Note that smtp_use_size and smtp_use_pipelining will have been
1044 set from the command line if they were set in the process that passed the
1049 inblock.sock = outblock.sock = fileno(stdin);
1050 smtp_command = big_buffer;
1051 host->port = port; /* Record the port that was used */
1054 /* If TLS is available on this connection, whether continued or not, attempt to
1055 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1056 send another EHLO - the server may give a different answer in secure mode. We
1057 use a separate buffer for reading the response to STARTTLS so that if it is
1058 negative, the original EHLO data is available for subsequent analysis, should
1059 the client not be required to use TLS. If the response is bad, copy the buffer
1060 for error analysis. */
1063 if (tls_offered && !suppress_tls &&
1064 verify_check_this_host(&(ob->hosts_avoid_tls), NULL, host->name,
1065 host->address, NULL) != OK)
1067 uschar buffer2[4096];
1068 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1071 /* If there is an I/O error, transmission of this message is deferred. If
1072 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1073 false, we also defer. However, if there is a temporary rejection of STARTTLS
1074 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1075 STARTTLS, we carry on. This means we will try to send the message in clear,
1076 unless the host is in hosts_require_tls (tested below). */
1078 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1079 ob->command_timeout))
1081 Ustrncpy(buffer, buffer2, sizeof(buffer));
1082 if (errno != 0 || buffer2[0] == 0 ||
1083 (buffer2[0] == '4' && !ob->tls_tempfail_tryclear))
1084 goto RESPONSE_FAILED;
1087 /* STARTTLS accepted: try to negotiate a TLS session. */
1091 int rc = tls_client_start(inblock.sock,
1094 NULL, /* No DH param */
1095 ob->tls_certificate,
1097 ob->tls_verify_certificates,
1099 ob->tls_require_ciphers,
1100 ob->gnutls_require_mac,
1101 ob->gnutls_require_kx,
1102 ob->gnutls_require_proto,
1103 ob->command_timeout);
1105 /* TLS negotiation failed; give an error. From outside, this function may
1106 be called again to try in clear on a new connection, if the options permit
1107 it for this host. */
1111 save_errno = ERRNO_TLSFAILURE;
1112 message = US"failure while setting up TLS session";
1117 /* TLS session is set up */
1119 for (addr = addrlist; addr != NULL; addr = addr->next)
1121 if (addr->transport_return == PENDING_DEFER)
1123 addr->cipher = tls_cipher;
1124 addr->peerdn = tls_peerdn;
1130 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1131 helo_data is null, we are dealing with a connection that was passed from
1132 another process, and so we won't have expanded helo_data above. We have to
1133 expand it here. $sending_ip_address and $sending_port are set up right at the
1134 start of the Exim process (in exim.c). */
1136 if (tls_active >= 0)
1138 if (helo_data == NULL)
1140 helo_data = expand_string(ob->helo_data);
1141 if (helo_data == NULL)
1143 uschar *message = string_sprintf("failed to expand helo_data: %s",
1144 expand_string_message);
1145 set_errno(addrlist, 0, message, DEFER, FALSE);
1151 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n", lmtp? "LHLO" : "EHLO",
1154 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1155 ob->command_timeout))
1156 goto RESPONSE_FAILED;
1159 /* If the host is required to use a secure channel, ensure that we
1162 else if (verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
1163 host->address, NULL) == OK)
1165 save_errno = ERRNO_TLSREQUIRED;
1166 message = string_sprintf("a TLS session is required for %s [%s], but %s",
1167 host->name, host->address,
1168 tls_offered? "an attempt to start TLS failed" :
1169 "the server did not offer TLS support");
1174 /* If TLS is active, we have just started it up and re-done the EHLO command,
1175 so its response needs to be analyzed. If TLS is not active and this is a
1176 continued session down a previously-used socket, we haven't just done EHLO, so
1179 if (continue_hostname == NULL
1186 uschar *fail_reason = US"server did not advertise AUTH support";
1188 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
1189 lmtp_ignore_quota option was set. */
1191 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1192 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1193 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1195 /* If the response to EHLO specified support for the SIZE parameter, note
1196 this, provided size_addition is non-negative. */
1198 smtp_use_size = esmtp && ob->size_addition >= 0 &&
1199 pcre_exec(regex_SIZE, NULL, CS buffer, Ustrlen(CS buffer), 0,
1200 PCRE_EOPT, NULL, 0) >= 0;
1202 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
1203 the current host, esmtp will be false, so PIPELINING can never be used. If
1204 the current host matches hosts_avoid_pipelining, don't do it. */
1206 smtp_use_pipelining = esmtp &&
1207 verify_check_this_host(&(ob->hosts_avoid_pipelining), NULL, host->name,
1208 host->address, NULL) != OK &&
1209 pcre_exec(regex_PIPELINING, NULL, CS buffer, Ustrlen(CS buffer), 0,
1210 PCRE_EOPT, NULL, 0) >= 0;
1212 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
1213 smtp_use_pipelining? "" : "not ");
1215 /* Note if the response to EHLO specifies support for the AUTH extension.
1216 If it has, check that this host is one we want to authenticate to, and do
1217 the business. The host name and address must be available when the
1218 authenticator's client driver is running. */
1220 smtp_authenticated = FALSE;
1221 require_auth = verify_check_this_host(&(ob->hosts_require_auth), NULL,
1222 host->name, host->address, NULL);
1224 if (esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
1226 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
1227 expand_nmax = -1; /* reset */
1229 /* Must not do this check until after we have saved the result of the
1230 regex match above. */
1232 if (require_auth == OK ||
1233 verify_check_this_host(&(ob->hosts_try_auth), NULL, host->name,
1234 host->address, NULL) == OK)
1237 fail_reason = US"no common mechanisms were found";
1239 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1241 /* Scan the configured authenticators looking for one which is configured
1242 for use as a client, which is not suppressed by client_condition, and
1243 whose name matches an authentication mechanism supported by the server.
1244 If one is found, attempt to authenticate by calling its client function.
1247 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1251 (au->client_condition != NULL &&
1252 !expand_check_condition(au->client_condition, au->name,
1253 US"client authenticator")))
1255 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1257 (au->client)? "client_condition is false" :
1258 "not configured as a client");
1262 /* Loop to scan supported server mechanisms */
1267 int len = Ustrlen(au->public_name);
1268 while (isspace(*p)) p++;
1270 if (strncmpic(au->public_name, p, len) != 0 ||
1271 (p[len] != 0 && !isspace(p[len])))
1273 while (*p != 0 && !isspace(*p)) p++;
1277 /* Found data for a listed mechanism. Call its client entry. Set
1278 a flag in the outblock so that data is overwritten after sending so
1279 that reflections don't show it. */
1281 fail_reason = US"authentication attempt(s) failed";
1282 outblock.authenticating = TRUE;
1283 rc = (au->info->clientcode)(au, &inblock, &outblock,
1284 ob->command_timeout, buffer, sizeof(buffer));
1285 outblock.authenticating = FALSE;
1286 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1289 /* A temporary authentication failure must hold up delivery to
1290 this host. After a permanent authentication failure, we carry on
1291 to try other authentication methods. If all fail hard, try to
1292 deliver the message unauthenticated unless require_auth was set. */
1297 smtp_authenticated = TRUE; /* stops the outer loop */
1300 /* Failure after writing a command */
1305 /* Failure after reading a response */
1308 if (errno != 0 || buffer[0] != '5') goto RESPONSE_FAILED;
1309 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1310 au->name, host->name, host->address, buffer);
1313 /* Failure by some other means. In effect, the authenticator
1314 decided it wasn't prepared to handle this case. Typically this
1315 is the result of "fail" in an expansion string. Do we need to
1316 log anything here? Feb 2006: a message is now put in the buffer
1317 if logging is required. */
1321 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1322 "authentication H=%s [%s] %s", au->name, host->name,
1323 host->address, buffer);
1326 /* Internal problem, message in buffer. */
1330 set_errno(addrlist, 0, string_copy(buffer), DEFER, FALSE);
1334 break; /* If not authenticated, try next authenticator */
1335 } /* Loop for scanning supported server mechanisms */
1336 } /* Loop for further authenticators */
1340 /* If we haven't authenticated, but are required to, give up. */
1342 if (require_auth == OK && !smtp_authenticated)
1345 set_errno(addrlist, ERRNO_AUTHFAIL,
1346 string_sprintf("authentication required but %s", fail_reason), DEFER,
1352 /* The setting up of the SMTP call is now complete. Any subsequent errors are
1353 message-specific. */
1357 /* If there is a filter command specified for this transport, we can now
1358 set it up. This cannot be done until the identify of the host is known. */
1360 if (tblock->filter_command != NULL)
1364 sprintf(CS buffer, "%.50s transport", tblock->name);
1365 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
1366 TRUE, DEFER, addrlist, buffer, NULL);
1367 transport_filter_timeout = tblock->filter_timeout;
1369 /* On failure, copy the error to all addresses, abandon the SMTP call, and
1374 set_errno(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
1382 /* For messages that have more than the maximum number of envelope recipients,
1383 we want to send several transactions down the same SMTP connection. (See
1384 comments in deliver.c as to how this reconciles, heuristically, with
1385 remote_max_parallel.) This optimization was added to Exim after the following
1386 code was already working. The simplest way to put it in without disturbing the
1387 code was to use a goto to jump back to this point when there is another
1388 transaction to handle. */
1391 sync_addr = first_addr;
1395 completed_address = FALSE;
1398 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
1399 qualification, send it, adding something to the message size to allow for
1400 imprecision and things that get added en route. Exim keeps the number of lines
1401 in a message, so we can give an accurate value for the original message, but we
1402 need some additional to handle added headers. (Double "." characters don't get
1403 included in the count.) */
1410 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
1414 /* Add the authenticated sender address if present */
1416 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1417 local_authenticated_sender != NULL)
1419 string_format(p, sizeof(buffer) - (p-buffer), " AUTH=%s",
1420 auth_xtextencode(local_authenticated_sender,
1421 Ustrlen(local_authenticated_sender)));
1424 /* From here until we send the DATA command, we can make use of PIPELINING
1425 if the server host supports it. The code has to be able to check the responses
1426 at any point, for when the buffer fills up, so we write it totally generally.
1427 When PIPELINING is off, each command written reports that it has flushed the
1430 pending_MAIL = TRUE; /* The block starts with MAIL */
1432 rc = smtp_write_command(&outblock, smtp_use_pipelining,
1433 "MAIL FROM:<%s>%s\r\n", return_path, buffer);
1434 mail_command = string_copy(big_buffer); /* Save for later error message */
1438 case -1: /* Transmission error */
1441 case +1: /* Block was sent */
1442 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1443 ob->command_timeout))
1445 if (errno == 0 && buffer[0] == '4')
1447 errno = ERRNO_MAIL4XX;
1448 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1450 goto RESPONSE_FAILED;
1452 pending_MAIL = FALSE;
1456 /* Pass over all the relevant recipient addresses for this host, which are the
1457 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
1458 several before we have to read the responses for those seen so far. This
1459 checking is done by a subroutine because it also needs to be done at the end.
1460 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
1461 the next one if not all are sent.
1463 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
1464 last address because we want to abort if any recipients have any kind of
1465 problem, temporary or permanent. We know that all recipient addresses will have
1466 the PENDING_DEFER status, because only one attempt is ever made, and we know
1467 that max_rcpt will be large, so all addresses will be done at once. */
1469 for (addr = first_addr;
1470 address_count < max_rcpt && addr != NULL;
1476 if (addr->transport_return != PENDING_DEFER) continue;
1479 no_flush = smtp_use_pipelining && (!mua_wrapper || addr->next != NULL);
1481 /* Now send the RCPT command, and process outstanding responses when
1482 necessary. After a timeout on RCPT, we just end the function, leaving the
1483 yield as OK, because this error can often mean that there is a problem with
1484 just one address, so we don't want to delay the host. */
1486 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s\r\n",
1487 transport_rcpt_address(addr, tblock->rcpt_include_affixes), igquotstr);
1488 if (count < 0) goto SEND_FAILED;
1491 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
1492 &sync_addr, host, count, ob->address_retry_include_sender,
1493 pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
1496 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1497 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1500 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1501 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1502 case 0: /* No 2xx or 5xx, but no probs */
1505 case -1: goto END_OFF; /* Timeout on RCPT */
1506 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
1508 pending_MAIL = FALSE; /* Dealt with MAIL */
1510 } /* Loop for next address */
1512 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
1513 permanently or temporarily. We should have flushed and synced after the last
1518 address_item *badaddr;
1519 for (badaddr = first_addr; badaddr != NULL; badaddr = badaddr->next)
1521 if (badaddr->transport_return != PENDING_OK) break;
1523 if (badaddr != NULL)
1525 set_errno(addrlist, 0, badaddr->message, FAIL,
1526 testflag(badaddr, af_pass_message));
1531 /* If ok is TRUE, we know we have got at least one good recipient, and must now
1532 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
1533 have a good recipient buffered up if we are pipelining. We don't want to waste
1534 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
1535 are pipelining. The responses are all handled by sync_responses(). */
1537 if (ok || (smtp_use_pipelining && !mua_wrapper))
1539 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
1540 if (count < 0) goto SEND_FAILED;
1541 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
1542 host, count, ob->address_retry_include_sender, pending_MAIL,
1543 ok? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
1545 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1546 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1549 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1550 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1551 case 0: break; /* No 2xx or 5xx, but no probs */
1553 case -1: goto END_OFF; /* Timeout on RCPT */
1554 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
1558 /* Save the first address of the next batch. */
1562 /* If there were no good recipients (but otherwise there have been no
1563 problems), just set ok TRUE, since we have handled address-specific errors
1564 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
1565 for handling the SMTP dot-handling protocol, flagging to apply to headers as
1566 well as body. Set the appropriate timeout value to be used for each chunk.
1567 (Haven't been able to make it work using select() for writing yet.) */
1569 if (!ok) ok = TRUE; else
1571 sigalrm_seen = FALSE;
1572 transport_write_timeout = ob->data_timeout;
1573 smtp_command = US"sending data block"; /* For error messages */
1574 DEBUG(D_transport|D_v)
1575 debug_printf(" SMTP>> writing message and terminating \".\"\n");
1576 transport_count = 0;
1577 #ifndef DISABLE_DKIM
1578 ok = dkim_transport_write_message(addrlist, inblock.sock,
1579 topt_use_crlf | topt_end_dot | topt_escape_headers |
1580 (tblock->body_only? topt_no_headers : 0) |
1581 (tblock->headers_only? topt_no_body : 0) |
1582 (tblock->return_path_add? topt_add_return_path : 0) |
1583 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1584 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1585 0, /* No size limit */
1586 tblock->add_headers, tblock->remove_headers,
1587 US".", US"..", /* Escaping strings */
1588 tblock->rewrite_rules, tblock->rewrite_existflags,
1589 ob->dkim_private_key, ob->dkim_domain, ob->dkim_selector,
1590 ob->dkim_canon, ob->dkim_strict, ob->dkim_sign_headers
1593 ok = transport_write_message(addrlist, inblock.sock,
1594 topt_use_crlf | topt_end_dot | topt_escape_headers |
1595 (tblock->body_only? topt_no_headers : 0) |
1596 (tblock->headers_only? topt_no_body : 0) |
1597 (tblock->return_path_add? topt_add_return_path : 0) |
1598 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1599 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1600 0, /* No size limit */
1601 tblock->add_headers, tblock->remove_headers,
1602 US".", US"..", /* Escaping strings */
1603 tblock->rewrite_rules, tblock->rewrite_existflags);
1606 /* transport_write_message() uses write() because it is called from other
1607 places to write to non-sockets. This means that under some OS (e.g. Solaris)
1608 it can exit with "Broken pipe" as its error. This really means that the
1609 socket got closed at the far end. */
1611 transport_write_timeout = 0; /* for subsequent transports */
1613 /* Failure can either be some kind of I/O disaster (including timeout),
1614 or the failure of a transport filter or the expansion of added headers. */
1618 buffer[0] = 0; /* There hasn't been a response */
1619 goto RESPONSE_FAILED;
1622 /* We used to send the terminating "." explicitly here, but because of
1623 buffering effects at both ends of TCP/IP connections, you don't gain
1624 anything by keeping it separate, so it might as well go in the final
1625 data buffer for efficiency. This is now done by setting the topt_end_dot
1628 smtp_command = US"end of data";
1630 /* For SMTP, we now read a single response that applies to the whole message.
1631 If it is OK, then all the addresses have been delivered. */
1635 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1637 if (!ok && errno == 0 && buffer[0] == '4')
1639 errno = ERRNO_DATA4XX;
1640 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1644 /* For LMTP, we get back a response for every RCPT command that we sent;
1645 some may be accepted and some rejected. For those that get a response, their
1646 status is fixed; any that are accepted have been handed over, even if later
1647 responses crash - at least, that's how I read RFC 2033.
1649 If all went well, mark the recipient addresses as completed, record which
1650 host/IPaddress they were delivered to, and cut out RSET when sending another
1651 message down the same channel. Write the completed addresses to the journal
1652 now so that they are recorded in case there is a crash of hardware or
1653 software before the spool gets updated. Also record the final SMTP
1654 confirmation if needed (for SMTP only). */
1659 int delivery_time = (int)(time(NULL) - start_delivery_time);
1662 uschar *conf = NULL;
1665 /* Make a copy of the host if it is local to this invocation
1666 of the transport. */
1670 thost = store_get(sizeof(host_item));
1672 thost->name = string_copy(host->name);
1673 thost->address = string_copy(host->address);
1677 /* Set up confirmation if needed - applies only to SMTP */
1679 if ((log_extra_selector & LX_smtp_confirmation) != 0 && !lmtp)
1681 uschar *s = string_printing(buffer);
1682 conf = (s == buffer)? (uschar *)string_copy(s) : s;
1685 /* Process all transported addresses - for LMTP, read a status for
1688 for (addr = addrlist; addr != first_addr; addr = addr->next)
1690 if (addr->transport_return != PENDING_OK) continue;
1692 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
1693 remaining addresses. Otherwise, it's a return code for just the one
1694 address. For temporary errors, add a retry item for the address so that
1695 it doesn't get tried again too soon. */
1699 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1702 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
1703 addr->message = string_sprintf("LMTP error after %s: %s",
1704 big_buffer, string_printing(buffer));
1705 setflag(addr, af_pass_message); /* Allow message to go to user */
1706 if (buffer[0] == '5')
1707 addr->transport_return = FAIL;
1710 errno = ERRNO_DATA4XX;
1711 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1712 addr->transport_return = DEFER;
1713 retry_add_item(addr, addr->address_retry_key, 0);
1717 completed_address = TRUE; /* NOW we can set this flag */
1718 if ((log_extra_selector & LX_smtp_confirmation) != 0)
1720 uschar *s = string_printing(buffer);
1721 conf = (s == buffer)? (uschar *)string_copy(s) : s;
1725 /* SMTP, or success return from LMTP for this address. Pass back the
1726 actual host that was used. */
1728 addr->transport_return = OK;
1729 addr->more_errno = delivery_time;
1730 addr->host_used = thost;
1731 addr->special_action = flag;
1732 addr->message = conf;
1735 /* Update the journal. For homonymic addresses, use the base address plus
1736 the transport name. See lots of comments in deliver.c about the reasons
1737 for the complications when homonyms are involved. Just carry on after
1738 write error, as it may prove possible to update the spool file later. */
1740 if (testflag(addr, af_homonym))
1741 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
1743 sprintf(CS buffer, "%.500s\n", addr->unique);
1745 DEBUG(D_deliver) debug_printf("journalling %s", buffer);
1746 len = Ustrlen(CS buffer);
1747 if (write(journal_fd, buffer, len) != len)
1748 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
1749 "%s: %s", buffer, strerror(errno));
1752 /* Ensure the journal file is pushed out to disk. */
1754 if (EXIMfsync(journal_fd) < 0)
1755 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
1761 /* Handle general (not specific to one address) failures here. The value of ok
1762 is used to skip over this code on the falling through case. A timeout causes a
1763 deferral. Other errors may defer or fail according to the response code, and
1764 may set up a special errno value, e.g. after connection chopped, which is
1765 assumed if errno == 0 and there is no text in the buffer. If control reaches
1766 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
1767 the problem is not related to this specific message. */
1776 send_quit = check_response(host, &save_errno, addrlist->more_errno,
1777 buffer, &code, &message, &pass_message);
1783 message = US string_sprintf("send() to %s [%s] failed: %s",
1784 host->name, host->address, strerror(save_errno));
1788 /* This label is jumped to directly when a TLS negotiation has failed,
1789 or was not done for a host for which it is required. Values will be set
1790 in message and save_errno, and setting_up will always be true. Treat as
1791 a temporary error. */
1798 /* If the failure happened while setting up the call, see if the failure was
1799 a 5xx response (this will either be on connection, or following HELO - a 5xx
1800 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
1801 never going to accept them. For other errors during setting up (timeouts or
1802 whatever), defer all addresses, and yield DEFER, so that the host is not
1803 tried again for a while. */
1806 ok = FALSE; /* For when reached by GOTO */
1812 set_errno(addrlist, save_errno, message, FAIL, pass_message);
1816 set_errno(addrlist, save_errno, message, DEFER, pass_message);
1821 /* We want to handle timeouts after MAIL or "." and loss of connection after
1822 "." specially. They can indicate a problem with the sender address or with
1823 the contents of the message rather than a real error on the connection. These
1824 cases are treated in the same way as a 4xx response. This next bit of code
1825 does the classification. */
1836 message_error = TRUE;
1840 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
1841 Ustrncmp(smtp_command,"end ",4) == 0;
1844 case ERRNO_SMTPCLOSED:
1845 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
1849 message_error = FALSE;
1853 /* Handle the cases that are treated as message errors. These are:
1855 (a) negative response or timeout after MAIL
1856 (b) negative response after DATA
1857 (c) negative response or timeout or dropped connection after "."
1859 It won't be a negative response or timeout after RCPT, as that is dealt
1860 with separately above. The action in all cases is to set an appropriate
1861 error code for all the addresses, but to leave yield set to OK because the
1862 host itself has not failed. Of course, it might in practice have failed
1863 when we've had a timeout, but if so, we'll discover that at the next
1864 delivery attempt. For a temporary error, set the message_defer flag, and
1865 write to the logs for information if this is not the last host. The error
1866 for the last host will be logged as part of the address's log line. */
1870 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
1871 set_errno(addrlist, save_errno, message, (code == '5')? FAIL : DEFER,
1874 /* If there's an errno, the message contains just the identity of
1877 if (code != '5') /* Anything other than 5 is treated as temporary */
1880 message = US string_sprintf("%s: %s", message, strerror(save_errno));
1881 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
1882 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
1883 *message_defer = TRUE;
1887 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
1888 ".", or some other transportation error. We defer all addresses and yield
1889 DEFER, except for the case of failed add_headers expansion, or a transport
1890 filter failure, when the yield should be ERROR, to stop it trying other
1895 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
1896 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
1897 set_errno(addrlist, save_errno, message, DEFER, pass_message);
1903 /* If all has gone well, send_quit will be set TRUE, implying we can end the
1904 SMTP session tidily. However, if there were too many addresses to send in one
1905 message (indicated by first_addr being non-NULL) we want to carry on with the
1906 rest of them. Also, it is desirable to send more than one message down the SMTP
1907 connection if there are several waiting, provided we haven't already sent so
1908 many as to hit the configured limit. The function transport_check_waiting looks
1909 for a waiting message and returns its id. Then transport_pass_socket tries to
1910 set up a continued delivery by passing the socket on to another process. The
1911 variable send_rset is FALSE if a message has just been successfully transfered.
1913 If we are already sending down a continued channel, there may be further
1914 addresses not yet delivered that are aimed at the same host, but which have not
1915 been passed in this run of the transport. In this case, continue_more will be
1916 true, and all we should do is send RSET if necessary, and return, leaving the
1919 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
1920 do not want to continue with other messages down the same channel, because that
1921 can lead to looping between two or more messages, all with the same,
1922 temporarily failing address(es). [The retry information isn't updated yet, so
1923 new processes keep on trying.] We probably also don't want to try more of this
1924 message's addresses either.
1926 If we have started a TLS session, we have to end it before passing the
1927 connection to a new process. However, not all servers can handle this (Exim
1928 can), so we do not pass such a connection on if the host matches
1929 hosts_nopass_tls. */
1932 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
1933 "yield=%d first_address is %sNULL\n", ok, send_quit, send_rset,
1934 continue_more, yield, (first_addr == NULL)? "":"not ");
1936 if (completed_address && ok && send_quit)
1939 if (first_addr != NULL || continue_more ||
1942 verify_check_this_host(&(ob->hosts_nopass_tls), NULL, host->name,
1943 host->address, NULL) != OK)
1945 transport_check_waiting(tblock->name, host->name,
1946 tblock->connection_max_messages, new_message_id, &more)
1954 if (! (ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
1956 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
1957 host->address, strerror(save_errno));
1960 else if (! (ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1961 ob->command_timeout)))
1964 send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
1968 DEBUG(D_transport) debug_printf("%s\n", msg);
1973 /* Either RSET was not needed, or it succeeded */
1977 if (first_addr != NULL) /* More addresses still to be sent */
1978 { /* in this run of the transport */
1979 continue_sequence++; /* Causes * in logging */
1982 if (continue_more) return yield; /* More addresses for another run */
1984 /* Pass the socket to a new Exim process. Before doing so, we must shut
1985 down TLS. Not all MTAs allow for the continuation of the SMTP session
1986 when TLS is shut down. We test for this by sending a new EHLO. If we
1987 don't get a good response, we don't attempt to pass the socket on. */
1990 if (tls_active >= 0)
1993 ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
1994 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1995 ob->command_timeout);
1999 /* If the socket is successfully passed, we musn't send QUIT (or
2000 indeed anything!) from here. */
2002 if (ok && transport_pass_socket(tblock->name, host->name, host->address,
2003 new_message_id, inblock.sock))
2009 /* If RSET failed and there are addresses left, they get deferred. */
2011 else set_errno(first_addr, errno, msg, DEFER, FALSE);
2015 /* End off tidily with QUIT unless the connection has died or the socket has
2016 been passed to another process. There has been discussion on the net about what
2017 to do after sending QUIT. The wording of the RFC suggests that it is necessary
2018 to wait for a response, but on the other hand, there isn't anything one can do
2019 with an error response, other than log it. Exim used to do that. However,
2020 further discussion suggested that it is positively advantageous not to wait for
2021 the response, but to close the session immediately. This is supposed to move
2022 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
2023 load from the server. (Hosts that are both servers and clients may not see much
2024 difference, of course.) Further discussion indicated that this was safe to do
2025 on Unix systems which have decent implementations of TCP/IP that leave the
2026 connection around for a while (TIME_WAIT) after the application has gone away.
2027 This enables the response sent by the server to be properly ACKed rather than
2028 timed out, as can happen on broken TCP/IP implementations on other OS.
2030 This change is being made on 31-Jul-98. After over a year of trouble-free
2031 operation, the old commented-out code was removed on 17-Sep-99. */
2034 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2042 /* Close the socket, and return the appropriate value, first setting
2043 continue_transport and continue_hostname NULL to prevent any other addresses
2044 that may include the host from trying to re-use a continuation socket. This
2045 works because the NULL setting is passed back to the calling process, and
2046 remote_max_parallel is forced to 1 when delivering over an existing connection,
2048 If all went well and continue_more is set, we shouldn't actually get here if
2049 there are further addresses, as the return above will be taken. However,
2050 writing RSET might have failed, or there may be other addresses whose hosts are
2051 specified in the transports, and therefore not visible at top level, in which
2052 case continue_more won't get set. */
2054 (void)close(inblock.sock);
2055 continue_transport = NULL;
2056 continue_hostname = NULL;
2063 /*************************************************
2064 * Closedown entry point *
2065 *************************************************/
2067 /* This function is called when exim is passed an open smtp channel
2068 from another incarnation, but the message which it has been asked
2069 to deliver no longer exists. The channel is on stdin.
2071 We might do fancy things like looking for another message to send down
2072 the channel, but if the one we sought has gone, it has probably been
2073 delivered by some other process that itself will seek further messages,
2074 so just close down our connection.
2076 Argument: pointer to the transport instance block
2081 smtp_transport_closedown(transport_instance *tblock)
2083 smtp_transport_options_block *ob =
2084 (smtp_transport_options_block *)(tblock->options_block);
2085 smtp_inblock inblock;
2086 smtp_outblock outblock;
2088 uschar inbuffer[4096];
2089 uschar outbuffer[16];
2091 inblock.sock = fileno(stdin);
2092 inblock.buffer = inbuffer;
2093 inblock.buffersize = sizeof(inbuffer);
2094 inblock.ptr = inbuffer;
2095 inblock.ptrend = inbuffer;
2097 outblock.sock = inblock.sock;
2098 outblock.buffersize = sizeof(outbuffer);
2099 outblock.buffer = outbuffer;
2100 outblock.ptr = outbuffer;
2101 outblock.cmd_count = 0;
2102 outblock.authenticating = FALSE;
2104 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2105 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2106 ob->command_timeout);
2107 (void)close(inblock.sock);
2112 /*************************************************
2113 * Prepare addresses for delivery *
2114 *************************************************/
2116 /* This function is called to flush out error settings from previous delivery
2117 attempts to other hosts. It also records whether we got here via an MX record
2118 or not in the more_errno field of the address. We are interested only in
2119 addresses that are still marked DEFER - others may have got delivered to a
2120 previously considered IP address. Set their status to PENDING_DEFER to indicate
2121 which ones are relevant this time.
2124 addrlist the list of addresses
2125 host the host we are delivering to
2127 Returns: the first address for this delivery
2130 static address_item *
2131 prepare_addresses(address_item *addrlist, host_item *host)
2133 address_item *first_addr = NULL;
2135 for (addr = addrlist; addr != NULL; addr = addr->next)
2137 if (addr->transport_return != DEFER) continue;
2138 if (first_addr == NULL) first_addr = addr;
2139 addr->transport_return = PENDING_DEFER;
2140 addr->basic_errno = 0;
2141 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
2142 addr->message = NULL;
2144 addr->cipher = NULL;
2145 addr->peerdn = NULL;
2153 /*************************************************
2154 * Main entry point *
2155 *************************************************/
2157 /* See local README for interface details. As this is a remote transport, it is
2158 given a chain of addresses to be delivered in one connection, if possible. It
2159 always returns TRUE, indicating that each address has its own independent
2160 status set, except if there is a setting up problem, in which case it returns
2164 smtp_transport_entry(
2165 transport_instance *tblock, /* data for this instantiation */
2166 address_item *addrlist) /* addresses we are working on */
2170 int hosts_defer = 0;
2172 int hosts_looked_up = 0;
2173 int hosts_retry = 0;
2174 int hosts_serial = 0;
2175 int hosts_total = 0;
2176 int total_hosts_tried = 0;
2178 BOOL expired = TRUE;
2179 BOOL continuing = continue_hostname != NULL;
2180 uschar *expanded_hosts = NULL;
2182 uschar *tid = string_sprintf("%s transport", tblock->name);
2183 smtp_transport_options_block *ob =
2184 (smtp_transport_options_block *)(tblock->options_block);
2185 host_item *hostlist = addrlist->host_list;
2186 host_item *host = NULL;
2190 debug_printf("%s transport entered\n", tblock->name);
2191 for (addr = addrlist; addr != NULL; addr = addr->next)
2192 debug_printf(" %s\n", addr->address);
2193 if (continuing) debug_printf("already connected to %s [%s]\n",
2194 continue_hostname, continue_host_address);
2197 /* Set the flag requesting that these hosts be added to the waiting
2198 database if the delivery fails temporarily or if we are running with
2199 queue_smtp or a 2-stage queue run. This gets unset for certain
2200 kinds of error, typically those that are specific to the message. */
2202 update_waiting = TRUE;
2204 /* If a host list is not defined for the addresses - they must all have the
2205 same one in order to be passed to a single transport - or if the transport has
2206 a host list with hosts_override set, use the host list supplied with the
2207 transport. It is an error for this not to exist. */
2209 if (hostlist == NULL || (ob->hosts_override && ob->hosts != NULL))
2211 if (ob->hosts == NULL)
2213 addrlist->message = string_sprintf("%s transport called with no hosts set",
2215 addrlist->transport_return = PANIC;
2216 return FALSE; /* Only top address has status */
2219 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
2222 /* If the transport's host list contains no '$' characters, and we are not
2223 randomizing, it is fixed and therefore a chain of hosts can be built once
2224 and for all, and remembered for subsequent use by other calls to this
2225 transport. If, on the other hand, the host list does contain '$', or we are
2226 randomizing its order, we have to rebuild it each time. In the fixed case,
2227 as the hosts string will never be used again, it doesn't matter that we
2228 replace all the : characters with zeros. */
2230 if (ob->hostlist == NULL)
2232 uschar *s = ob->hosts;
2234 if (Ustrchr(s, '$') != NULL)
2236 expanded_hosts = expand_string(s);
2237 if (expanded_hosts == NULL)
2239 addrlist->message = string_sprintf("failed to expand list of hosts "
2240 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
2241 addrlist->transport_return = search_find_defer? DEFER : PANIC;
2242 return FALSE; /* Only top address has status */
2244 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
2245 "\"%s\"\n", s, expanded_hosts);
2249 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
2251 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
2253 /* Check that the expansion yielded something useful. */
2254 if (hostlist == NULL)
2257 string_sprintf("%s transport has empty hosts setting", tblock->name);
2258 addrlist->transport_return = PANIC;
2259 return FALSE; /* Only top address has status */
2262 /* If there was no expansion of hosts, save the host list for
2265 if (expanded_hosts == NULL) ob->hostlist = hostlist;
2268 /* This is not the first time this transport has been run in this delivery;
2269 the host list was built previously. */
2271 else hostlist = ob->hostlist;
2274 /* The host list was supplied with the address. If hosts_randomize is set, we
2275 must sort it into a random order if it did not come from MX records and has not
2276 already been randomized (but don't bother if continuing down an existing
2279 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continuing)
2281 host_item *newlist = NULL;
2282 while (hostlist != NULL)
2284 host_item *h = hostlist;
2285 hostlist = hostlist->next;
2287 h->sort_key = random_number(100);
2289 if (newlist == NULL)
2294 else if (h->sort_key < newlist->sort_key)
2301 host_item *hh = newlist;
2302 while (hh->next != NULL)
2304 if (h->sort_key < hh->next->sort_key) break;
2312 hostlist = addrlist->host_list = newlist;
2316 /* Sort out the default port. */
2318 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
2321 /* For each host-plus-IP-address on the list:
2323 . If this is a continued delivery and the host isn't the one with the
2324 current connection, skip.
2326 . If the status is unusable (i.e. previously failed or retry checked), skip.
2328 . If no IP address set, get the address, either by turning the name into
2329 an address, calling gethostbyname if gethostbyname is on, or by calling
2330 the DNS. The DNS may yield multiple addresses, in which case insert the
2331 extra ones into the list.
2333 . Get the retry data if not previously obtained for this address and set the
2334 field which remembers the state of this address. Skip if the retry time is
2335 not reached. If not, remember whether retry data was found. The retry string
2336 contains both the name and the IP address.
2338 . Scan the list of addresses and mark those whose status is DEFER as
2339 PENDING_DEFER. These are the only ones that will be processed in this cycle
2342 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
2343 Some addresses may be successfully delivered, others may fail, and yet
2344 others may get temporary errors and so get marked DEFER.
2346 . The return from the delivery attempt is OK if a connection was made and a
2347 valid SMTP dialogue was completed. Otherwise it is DEFER.
2349 . If OK, add a "remove" retry item for this host/IPaddress, if any.
2351 . If fail to connect, or other defer state, add a retry item.
2353 . If there are any addresses whose status is still DEFER, carry on to the
2354 next host/IPaddress, unless we have tried the number of hosts given
2355 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
2356 there is some fancy logic for hosts_max_try that means its limit can be
2357 overstepped in some circumstances.
2359 If we get to the end of the list, all hosts have deferred at least one address,
2360 or not reached their retry times. If delay_after_cutoff is unset, it requests a
2361 delivery attempt to those hosts whose last try was before the arrival time of
2362 the current message. To cope with this, we have to go round the loop a second
2363 time. After that, set the status and error data for any addresses that haven't
2364 had it set already. */
2366 for (cutoff_retry = 0; expired &&
2367 cutoff_retry < ((ob->delay_after_cutoff)? 1 : 2);
2370 host_item *nexthost = NULL;
2371 int unexpired_hosts_tried = 0;
2373 for (host = hostlist;
2375 unexpired_hosts_tried < ob->hosts_max_try &&
2376 total_hosts_tried < ob->hosts_max_try_hardlimit;
2382 BOOL serialized = FALSE;
2383 BOOL host_is_expired = FALSE;
2384 BOOL message_defer = FALSE;
2385 BOOL ifchanges = FALSE;
2386 BOOL some_deferred = FALSE;
2387 address_item *first_addr = NULL;
2388 uschar *interface = NULL;
2389 uschar *retry_host_key = NULL;
2390 uschar *retry_message_key = NULL;
2391 uschar *serialize_key = NULL;
2393 /* Default next host is next host. :-) But this can vary if the
2394 hosts_max_try limit is hit (see below). It may also be reset if a host
2395 address is looked up here (in case the host was multihomed). */
2397 nexthost = host->next;
2399 /* If the address hasn't yet been obtained from the host name, look it up
2400 now, unless the host is already marked as unusable. If it is marked as
2401 unusable, it means that the router was unable to find its IP address (in
2402 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
2403 the lookup failed last time. We don't get this far if *all* MX records
2404 point to non-existent hosts; that is treated as a hard error.
2406 We can just skip this host entirely. When the hosts came from the router,
2407 the address will timeout based on the other host(s); when the address is
2408 looked up below, there is an explicit retry record added.
2410 Note that we mustn't skip unusable hosts if the address is not unset; they
2411 may be needed as expired hosts on the 2nd time round the cutoff loop. */
2413 if (host->address == NULL)
2415 int new_port, flags;
2417 uschar *canonical_name;
2419 if (host->status >= hstatus_unusable)
2421 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
2426 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
2428 /* The host name is permitted to have an attached port. Find it, and
2429 strip it from the name. Just remember it for now. */
2431 new_port = host_item_get_port(host);
2433 /* Count hosts looked up */
2437 /* Find by name if so configured, or if it's an IP address. We don't
2438 just copy the IP address, because we need the test-for-local to happen. */
2440 flags = HOST_FIND_BY_A;
2441 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
2442 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
2444 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
2445 rc = host_find_byname(host, NULL, flags, &canonical_name, TRUE);
2447 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
2448 &canonical_name, NULL);
2450 /* Update the host (and any additional blocks, resulting from
2451 multihoming) with a host-specific port, if any. */
2453 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
2455 /* Failure to find the host at this time (usually DNS temporary failure)
2456 is really a kind of routing failure rather than a transport failure.
2457 Therefore we add a retry item of the routing kind, not to stop us trying
2458 to look this name up here again, but to ensure the address gets timed
2459 out if the failures go on long enough. A complete failure at this point
2460 commonly points to a configuration error, but the best action is still
2461 to carry on for the next host. */
2463 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
2465 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
2467 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
2468 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
2469 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
2470 host->status = hstatus_unusable;
2472 for (addr = addrlist; addr != NULL; addr = addr->next)
2474 if (addr->transport_return != DEFER) continue;
2475 addr->basic_errno = ERRNO_UNKNOWNHOST;
2477 string_sprintf("failed to lookup IP address for %s", host->name);
2482 /* If the host is actually the local host, we may have a problem, or
2483 there may be some cunning configuration going on. In the problem case,
2484 log things and give up. The default transport status is already DEFER. */
2486 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
2488 for (addr = addrlist; addr != NULL; addr = addr->next)
2490 addr->basic_errno = 0;
2491 addr->message = string_sprintf("%s transport found host %s to be "
2492 "local", tblock->name, host->name);
2496 } /* End of block for IP address lookup */
2498 /* If this is a continued delivery, we are interested only in the host
2499 which matches the name of the existing open channel. The check is put
2500 here after the local host lookup, in case the name gets expanded as a
2501 result of the lookup. Set expired FALSE, to save the outer loop executing
2504 if (continuing && (Ustrcmp(continue_hostname, host->name) != 0 ||
2505 Ustrcmp(continue_host_address, host->address) != 0))
2508 continue; /* With next host */
2511 /* Reset the default next host in case a multihomed host whose addresses
2512 are not looked up till just above added to the host list. */
2514 nexthost = host->next;
2516 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
2517 domain is in queue_smtp_domains, we don't actually want to attempt any
2518 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
2519 there is a lookup defer in queue_smtp_domains, proceed as if the domain
2520 were not in it. We don't want to hold up all SMTP deliveries! Except when
2521 doing a two-stage queue run, don't do this if forcing. */
2523 if ((!deliver_force || queue_2stage) && (queue_smtp ||
2524 match_isinlist(addrlist->domain, &queue_smtp_domains, 0,
2525 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
2528 for (addr = addrlist; addr != NULL; addr = addr->next)
2530 if (addr->transport_return != DEFER) continue;
2531 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
2533 continue; /* With next host */
2536 /* Count hosts being considered - purely for an intelligent comment
2537 if none are usable. */
2541 /* Set $host and $host address now in case they are needed for the
2542 interface expansion or the serialize_hosts check; they remain set if an
2543 actual delivery happens. */
2545 deliver_host = host->name;
2546 deliver_host_address = host->address;
2548 /* Set up a string for adding to the retry key if the port number is not
2549 the standard SMTP port. A host may have its own port setting that overrides
2552 pistring = string_sprintf(":%d", (host->port == PORT_NONE)?
2554 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
2556 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
2557 string changes upon expansion, we must add it to the key that is used for
2558 retries, because connections to the same host from a different interface
2559 should be treated separately. */
2561 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET : AF_INET6;
2562 if (!smtp_get_interface(ob->interface, host_af, addrlist, &ifchanges,
2565 if (ifchanges) pistring = string_sprintf("%s/%s", pistring, interface);
2567 /* The first time round the outer loop, check the status of the host by
2568 inspecting the retry data. The second time round, we are interested only
2569 in expired hosts that haven't been tried since this message arrived. */
2571 if (cutoff_retry == 0)
2573 /* Ensure the status of the address is set by checking retry data if
2574 necessary. There maybe host-specific retry data (applicable to all
2575 messages) and also data for retries of a specific message at this host.
2576 If either of these retry records are actually read, the keys used are
2577 returned to save recomputing them later. */
2579 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
2580 ob->retry_include_ip_address, &retry_host_key, &retry_message_key);
2582 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
2583 (host->address == NULL)? US"" : host->address, pistring,
2584 (host->status == hstatus_usable)? "usable" :
2585 (host->status == hstatus_unusable)? "unusable" :
2586 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
2588 /* Skip this address if not usable at this time, noting if it wasn't
2589 actually expired, both locally and in the address. */
2591 switch (host->status)
2593 case hstatus_unusable:
2595 setflag(addrlist, af_retry_skipped);
2598 case hstatus_unusable_expired:
2601 case hwhy_retry: hosts_retry++; break;
2602 case hwhy_failed: hosts_fail++; break;
2603 case hwhy_deferred: hosts_defer++; break;
2606 /* If there was a retry message key, implying that previously there
2607 was a message-specific defer, we don't want to update the list of
2608 messages waiting for these hosts. */
2610 if (retry_message_key != NULL) update_waiting = FALSE;
2611 continue; /* With the next host or IP address */
2615 /* Second time round the loop: if the address is set but expired, and
2616 the message is newer than the last try, let it through. */
2620 if (host->address == NULL ||
2621 host->status != hstatus_unusable_expired ||
2622 host->last_try > received_time)
2625 debug_printf("trying expired host %s [%s]%s\n",
2626 host->name, host->address, pistring);
2627 host_is_expired = TRUE;
2630 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
2631 it remains TRUE only if all hosts are expired and none are actually tried.
2636 /* If this host is listed as one to which access must be serialized,
2637 see if another Exim process has a connection to it, and if so, skip
2638 this host. If not, update the database to record our connection to it
2639 and remember this for later deletion. Do not do any of this if we are
2640 sending the message down a pre-existing connection. */
2643 verify_check_this_host(&(ob->serialize_hosts), NULL, host->name,
2644 host->address, NULL) == OK)
2646 serialize_key = string_sprintf("host-serialize-%s", host->name);
2647 if (!enq_start(serialize_key))
2650 debug_printf("skipping host %s because another Exim process "
2651 "is connected to it\n", host->name);
2658 /* OK, we have an IP address that is not waiting for its retry time to
2659 arrive (it might be expired) OR (second time round the loop) we have an
2660 expired host that hasn't been tried since the message arrived. Have a go
2661 at delivering the message to it. First prepare the addresses by flushing
2662 out the result of previous attempts, and finding the first address that
2663 is still to be delivered. */
2665 first_addr = prepare_addresses(addrlist, host);
2667 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
2668 message_id, host->name, host->address, addrlist->address,
2669 (addrlist->next == NULL)? "" : ", ...");
2671 set_process_info("delivering %s to %s [%s] (%s%s)",
2672 message_id, host->name, host->address, addrlist->address,
2673 (addrlist->next == NULL)? "" : ", ...");
2675 /* This is not for real; don't do the delivery. If there are
2676 any remaining hosts, list them. */
2681 set_errno(addrlist, 0, NULL, OK, FALSE);
2682 for (addr = addrlist; addr != NULL; addr = addr->next)
2684 addr->host_used = host;
2685 addr->special_action = '*';
2686 addr->message = US"delivery bypassed by -N option";
2690 debug_printf("*** delivery by %s transport bypassed by -N option\n"
2691 "*** host and remaining hosts:\n", tblock->name);
2692 for (host2 = host; host2 != NULL; host2 = host2->next)
2693 debug_printf(" %s [%s]\n", host2->name,
2694 (host2->address == NULL)? US"unset" : host2->address);
2699 /* This is for real. If the host is expired, we don't count it for
2700 hosts_max_retry. This ensures that all hosts must expire before an address
2701 is timed out, unless hosts_max_try_hardlimit (which protects against
2702 lunatic DNS configurations) is reached.
2704 If the host is not expired and we are about to hit the hosts_max_retry
2705 limit, check to see if there is a subsequent hosts with a different MX
2706 value. If so, make that the next host, and don't count this one. This is a
2707 heuristic to make sure that different MXs do get tried. With a normal kind
2708 of retry rule, they would get tried anyway when the earlier hosts were
2709 delayed, but if the domain has a "retry every time" type of rule - as is
2710 often used for the the very large ISPs, that won't happen. */
2714 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
2718 debug_printf("hosts_max_try limit reached with this host\n");
2719 for (h = host; h != NULL; h = h->next)
2720 if (h->mx != host->mx) break;
2724 unexpired_hosts_tried--;
2725 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
2726 "and will be tried\n");
2730 /* Attempt the delivery. */
2732 total_hosts_tried++;
2733 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
2734 expanded_hosts != NULL, &message_defer, FALSE);
2737 OK => connection made, each address contains its result;
2738 message_defer is set for message-specific defers (when all
2739 recipients are marked defer)
2740 DEFER => there was a non-message-specific delivery problem;
2741 ERROR => there was a problem setting up the arguments for a filter,
2742 or there was a problem with expanding added headers
2745 /* If the result is not OK, there was a non-message-specific problem.
2746 If the result is DEFER, we need to write to the logs saying what happened
2747 for this particular host, except in the case of authentication and TLS
2748 failures, where the log has already been written. If all hosts defer a
2749 general message is written at the end. */
2751 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL &&
2752 first_addr->basic_errno != ERRNO_TLSFAILURE)
2753 write_logs(first_addr, host);
2755 /* If STARTTLS was accepted, but there was a failure in setting up the
2756 TLS session (usually a certificate screwup), and the host is not in
2757 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
2758 TLS forcibly turned off. We have to start from scratch with a new SMTP
2759 connection. That's why the retry is done from here, not from within
2760 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
2761 session, so the in-clear transmission after those errors, if permitted,
2762 happens inside smtp_deliver().] */
2765 if (rc == DEFER && first_addr->basic_errno == ERRNO_TLSFAILURE &&
2766 ob->tls_tempfail_tryclear &&
2767 verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
2768 host->address, NULL) != OK)
2770 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
2771 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
2772 first_addr = prepare_addresses(addrlist, host);
2773 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
2774 expanded_hosts != NULL, &message_defer, TRUE);
2775 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
2776 write_logs(first_addr, host);
2781 /* Delivery attempt finished */
2783 rs = (rc == OK)? US"OK" : (rc == DEFER)? US"DEFER" : (rc == ERROR)?
2786 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
2787 message_id, host->name, host->address, addrlist->address,
2788 (addrlist->next == NULL)? "" : " (& others)", rs);
2790 /* Release serialization if set up */
2792 if (serialized) enq_end(serialize_key);
2794 /* If the result is DEFER, or if a host retry record is known to exist, we
2795 need to add an item to the retry chain for updating the retry database
2796 at the end of delivery. We only need to add the item to the top address,
2797 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
2798 for any other delivery attempts using the same address. (It is copied into
2799 the unusable tree at the outer level, so even if different address blocks
2800 contain the same address, it still won't get tried again.) */
2802 if (rc == DEFER || retry_host_key != NULL)
2804 int delete_flag = (rc != DEFER)? rf_delete : 0;
2805 if (retry_host_key == NULL)
2807 retry_host_key = ob->retry_include_ip_address?
2808 string_sprintf("T:%S:%s%s", host->name, host->address, pistring) :
2809 string_sprintf("T:%S%s", host->name, pistring);
2812 /* If a delivery of another message over an existing SMTP connection
2813 yields DEFER, we do NOT set up retry data for the host. This covers the
2814 case when there are delays in routing the addresses in the second message
2815 that are so long that the server times out. This is alleviated by not
2816 routing addresses that previously had routing defers when handling an
2817 existing connection, but even so, this case may occur (e.g. if a
2818 previously happily routed address starts giving routing defers). If the
2819 host is genuinely down, another non-continued message delivery will
2820 notice it soon enough. */
2822 if (delete_flag != 0 || !continuing)
2823 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
2825 /* We may have tried an expired host, if its retry time has come; ensure
2826 the status reflects the expiry for the benefit of any other addresses. */
2830 host->status = (host_is_expired)?
2831 hstatus_unusable_expired : hstatus_unusable;
2832 host->why = hwhy_deferred;
2836 /* If message_defer is set (host was OK, but every recipient got deferred
2837 because of some message-specific problem), or if that had happened
2838 previously so that a message retry key exists, add an appropriate item
2839 to the retry chain. Note that if there was a message defer but now there is
2840 a host defer, the message defer record gets deleted. That seems perfectly
2841 reasonable. Also, stop the message from being remembered as waiting
2842 for specific hosts. */
2844 if (message_defer || retry_message_key != NULL)
2846 int delete_flag = message_defer? 0 : rf_delete;
2847 if (retry_message_key == NULL)
2849 retry_message_key = ob->retry_include_ip_address?
2850 string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
2852 string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
2854 retry_add_item(addrlist, retry_message_key,
2855 rf_message | rf_host | delete_flag);
2856 update_waiting = FALSE;
2859 /* Any return other than DEFER (that is, OK or ERROR) means that the
2860 addresses have got their final statuses filled in for this host. In the OK
2861 case, see if any of them are deferred. */
2865 for (addr = addrlist; addr != NULL; addr = addr->next)
2867 if (addr->transport_return == DEFER)
2869 some_deferred = TRUE;
2875 /* If no addresses deferred or the result was ERROR, return. We do this for
2876 ERROR because a failing filter set-up or add_headers expansion is likely to
2877 fail for any host we try. */
2879 if (rc == ERROR || (rc == OK && !some_deferred))
2881 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
2882 return TRUE; /* Each address has its status */
2885 /* If the result was DEFER or some individual addresses deferred, let
2886 the loop run to try other hosts with the deferred addresses, except for the
2887 case when we were trying to deliver down an existing channel and failed.
2888 Don't try any other hosts in this case. */
2890 if (continuing) break;
2892 /* If the whole delivery, or some individual addresses, were deferred and
2893 there are more hosts that could be tried, do not count this host towards
2894 the hosts_max_try limit if the age of the message is greater than the
2895 maximum retry time for this host. This means we may try try all hosts,
2896 ignoring the limit, when messages have been around for some time. This is
2897 important because if we don't try all hosts, the address will never time
2898 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
2900 if ((rc == DEFER || some_deferred) && nexthost != NULL)
2903 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
2905 if (retry != NULL && retry->rules != NULL)
2907 retry_rule *last_rule;
2908 for (last_rule = retry->rules;
2909 last_rule->next != NULL;
2910 last_rule = last_rule->next);
2911 timedout = time(NULL) - received_time > last_rule->timeout;
2913 else timedout = TRUE; /* No rule => timed out */
2917 unexpired_hosts_tried--;
2918 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
2919 "hosts_max_try (message older than host's retry time)\n");
2922 } /* End of loop for trying multiple hosts. */
2924 /* This is the end of the loop that repeats iff expired is TRUE and
2925 ob->delay_after_cutoff is FALSE. The second time round we will
2926 try those hosts that haven't been tried since the message arrived. */
2930 debug_printf("all IP addresses skipped or deferred at least one address\n");
2931 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
2932 debug_printf("retrying IP addresses not tried since message arrived\n");
2937 /* Get here if all IP addresses are skipped or defer at least one address. In
2938 MUA wrapper mode, this will happen only for connection or other non-message-
2939 specific failures. Force the delivery status for all addresses to FAIL. */
2943 for (addr = addrlist; addr != NULL; addr = addr->next)
2944 addr->transport_return = FAIL;
2948 /* In the normal, non-wrapper case, add a standard message to each deferred
2949 address if there hasn't been an error, that is, if it hasn't actually been
2950 tried this time. The variable "expired" will be FALSE if any deliveries were
2951 actually tried, or if there was at least one host that was not expired. That
2952 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
2953 a delivery has been tried, an error code will be set, and the failing of the
2954 message is handled by the retry code later.
2956 If queue_smtp is set, or this transport was called to send a subsequent message
2957 down an existing TCP/IP connection, and something caused the host not to be
2958 found, we end up here, but can detect these cases and handle them specially. */
2960 for (addr = addrlist; addr != NULL; addr = addr->next)
2962 /* If host is not NULL, it means that we stopped processing the host list
2963 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
2964 means we need to behave as if some hosts were skipped because their retry
2965 time had not come. Specifically, this prevents the address from timing out.
2966 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
2967 hosts were tried. */
2971 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
2974 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
2975 "hosts were tried\n");
2980 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
2981 setflag(addr, af_retry_skipped);
2985 if (queue_smtp) /* no deliveries attempted */
2987 addr->transport_return = DEFER;
2988 addr->basic_errno = 0;
2989 addr->message = US"SMTP delivery explicitly queued";
2992 else if (addr->transport_return == DEFER &&
2993 (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0) &&
2994 addr->message == NULL)
2996 addr->basic_errno = ERRNO_HRETRY;
2997 if (continue_hostname != NULL)
2999 addr->message = US"no host found for existing SMTP connection";
3003 setflag(addr, af_pass_message); /* This is not a security risk */
3004 addr->message = (ob->delay_after_cutoff)?
3005 US"retry time not reached for any host after a long failure period" :
3006 US"all hosts have been failing for a long time and were last tried "
3007 "after this message arrived";
3009 /* If we are already using fallback hosts, or there are no fallback hosts
3010 defined, convert the result to FAIL to cause a bounce. */
3012 if (addr->host_list == addr->fallback_hosts ||
3013 addr->fallback_hosts == NULL)
3014 addr->transport_return = FAIL;
3018 if (hosts_retry == hosts_total)
3019 addr->message = US"retry time not reached for any host";
3020 else if (hosts_fail == hosts_total)
3021 addr->message = US"all host address lookups failed permanently";
3022 else if (hosts_defer == hosts_total)
3023 addr->message = US"all host address lookups failed temporarily";
3024 else if (hosts_serial == hosts_total)
3025 addr->message = US"connection limit reached for all hosts";
3026 else if (hosts_fail+hosts_defer == hosts_total)
3027 addr->message = US"all host address lookups failed";
3028 else addr->message = US"some host address lookups failed and retry time "
3029 "not reached for other hosts or connection limit reached";
3034 /* Update the database which keeps information about which messages are waiting
3035 for which hosts to become available. For some message-specific errors, the
3036 update_waiting flag is turned off because we don't want follow-on deliveries in
3039 if (update_waiting) transport_update_waiting(hostlist, tblock->name);
3043 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3045 return TRUE; /* Each address has its status */
3048 /* End of transport/smtp.c */