1 /* $Cambridge: exim/src/src/transports/smtp.c,v 1.36 2007/02/08 15:16:19 ph10 Exp $ */
3 /*************************************************
4 * Exim - an Internet mail transport agent *
5 *************************************************/
7 /* Copyright (c) University of Cambridge 1995 - 2007 */
8 /* See the file NOTICE for conditions of use and distribution. */
14 #define PENDING_DEFER (PENDING + DEFER)
15 #define PENDING_OK (PENDING + OK)
18 /* Options specific to the smtp transport. This transport also supports LMTP
19 over TCP/IP. The options must be in alphabetic order (note that "_" comes
20 before the lower case letters). Some live in the transport_instance block so as
21 to be publicly visible; these are flagged with opt_public. */
23 optionlist smtp_transport_options[] = {
24 { "address_retry_include_sender", opt_bool,
25 (void *)offsetof(smtp_transport_options_block, address_retry_include_sender) },
26 { "allow_localhost", opt_bool,
27 (void *)offsetof(smtp_transport_options_block, allow_localhost) },
28 { "authenticated_sender", opt_stringptr,
29 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
30 { "authenticated_sender_force", opt_bool,
31 (void *)offsetof(smtp_transport_options_block, authenticated_sender_force) },
32 { "command_timeout", opt_time,
33 (void *)offsetof(smtp_transport_options_block, command_timeout) },
34 { "connect_timeout", opt_time,
35 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
36 { "connection_max_messages", opt_int | opt_public,
37 (void *)offsetof(transport_instance, connection_max_messages) },
38 { "data_timeout", opt_time,
39 (void *)offsetof(smtp_transport_options_block, data_timeout) },
40 { "delay_after_cutoff", opt_bool,
41 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
42 #ifdef EXPERIMENTAL_DOMAINKEYS
43 { "dk_canon", opt_stringptr,
44 (void *)offsetof(smtp_transport_options_block, dk_canon) },
45 { "dk_domain", opt_stringptr,
46 (void *)offsetof(smtp_transport_options_block, dk_domain) },
47 { "dk_headers", opt_stringptr,
48 (void *)offsetof(smtp_transport_options_block, dk_headers) },
49 { "dk_private_key", opt_stringptr,
50 (void *)offsetof(smtp_transport_options_block, dk_private_key) },
51 { "dk_selector", opt_stringptr,
52 (void *)offsetof(smtp_transport_options_block, dk_selector) },
53 { "dk_strict", opt_stringptr,
54 (void *)offsetof(smtp_transport_options_block, dk_strict) },
56 { "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 */
198 #ifdef EXPERIMENTAL_DOMAINKEYS
199 ,NULL, /* dk_canon */
200 NULL, /* dk_domain */
201 NULL, /* dk_headers */
202 NULL, /* dk_private_key */
203 NULL, /* dk_selector */
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
794 Otherwise, we have to make a connection to the remote host, and do the
795 initial protocol exchange.
797 When running as an MUA wrapper, if the sender or any recipient is rejected,
798 temporarily or permanently, we force failure for all recipients.
801 addrlist chain of potential addresses to deliver; only those whose
802 transport_return field is set to PENDING_DEFER are currently
803 being processed; others should be skipped - they have either
804 been delivered to an earlier host or IP address, or been
805 failed by one of them.
806 host host to deliver to
807 host_af AF_INET or AF_INET6
808 port default TCP/IP port to use, in host byte order
809 interface interface to bind to, or NULL
810 tblock transport instance block
811 copy_host TRUE if host set in addr->host_used must be copied, because
812 it is specific to this call of the transport
813 message_defer set TRUE if yield is OK, but all addresses were deferred
814 because of a non-recipient, non-host failure, that is, a
815 4xx response to MAIL FROM, DATA, or ".". This is a defer
816 that is specific to the message.
817 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
818 a second attempt after TLS initialization fails
820 Returns: OK - the connection was made and the delivery attempted;
821 the result for each address is in its data block.
822 DEFER - the connection could not be made, or something failed
823 while setting up the SMTP session, or there was a
824 non-message-specific error, such as a timeout.
825 ERROR - a filter command is specified for this transport,
826 and there was a problem setting it up; OR helo_data
827 or add_headers or authenticated_sender is specified
828 for this transport, and the string failed to expand
832 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
833 uschar *interface, transport_instance *tblock, BOOL copy_host,
834 BOOL *message_defer, BOOL suppress_tls)
837 address_item *sync_addr;
838 address_item *first_addr = addrlist;
843 time_t start_delivery_time = time(NULL);
844 smtp_transport_options_block *ob =
845 (smtp_transport_options_block *)(tblock->options_block);
846 BOOL lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
848 BOOL send_rset = TRUE;
849 BOOL send_quit = TRUE;
850 BOOL setting_up = TRUE;
851 BOOL completed_address = FALSE;
854 BOOL pass_message = FALSE;
855 smtp_inblock inblock;
856 smtp_outblock outblock;
857 int max_rcpt = tblock->max_addresses;
858 uschar *igquotstr = US"";
859 uschar *local_authenticated_sender = authenticated_sender;
860 uschar *helo_data = NULL;
861 uschar *message = NULL;
862 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
865 uschar inbuffer[4096];
866 uschar outbuffer[1024];
868 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
870 *message_defer = FALSE;
871 smtp_command = US"initial connection";
872 if (max_rcpt == 0) max_rcpt = 999999;
874 /* Set up the buffer for reading SMTP response packets. */
876 inblock.buffer = inbuffer;
877 inblock.buffersize = sizeof(inbuffer);
878 inblock.ptr = inbuffer;
879 inblock.ptrend = inbuffer;
881 /* Set up the buffer for holding SMTP commands while pipelining */
883 outblock.buffer = outbuffer;
884 outblock.buffersize = sizeof(outbuffer);
885 outblock.ptr = outbuffer;
886 outblock.cmd_count = 0;
887 outblock.authenticating = FALSE;
889 /* If an authenticated_sender override has been specified for this transport
890 instance, expand it. If the expansion is forced to fail, and there was already
891 an authenticated_sender for this message, the original value will be used.
892 Other expansion failures are serious. An empty result is ignored, but there is
893 otherwise no check - this feature is expected to be used with LMTP and other
894 cases where non-standard addresses (e.g. without domains) might be required. */
896 if (ob->authenticated_sender != NULL)
898 uschar *new = expand_string(ob->authenticated_sender);
901 if (!expand_string_forcedfail)
903 uschar *message = string_sprintf("failed to expand "
904 "authenticated_sender: %s", expand_string_message);
905 set_errno(addrlist, 0, message, DEFER, FALSE);
909 else if (new[0] != 0) local_authenticated_sender = new;
912 /* Make a connection to the host if this isn't a continued delivery, and handle
913 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
914 specially so they can be identified for retries. */
916 if (continue_hostname == NULL)
918 inblock.sock = outblock.sock =
919 smtp_connect(host, host_af, port, interface, ob->connect_timeout,
920 ob->keepalive); /* This puts port into host->port */
922 if (inblock.sock < 0)
924 set_errno(addrlist, (errno == ETIMEDOUT)? ERRNO_CONNECTTIMEOUT : errno,
929 /* Expand the greeting message while waiting for the initial response. (Makes
930 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
931 delayed till here so that $sending_interface and $sending_port are set. */
933 helo_data = expand_string(ob->helo_data);
935 /* The first thing is to wait for an initial OK response. The dreaded "goto"
936 is nevertheless a reasonably clean way of programming this kind of logic,
937 where you want to escape on any error. */
939 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
940 ob->command_timeout)) goto RESPONSE_FAILED;
942 /* Now check if the helo_data expansion went well, and sign off cleanly if it
945 if (helo_data == NULL)
947 uschar *message = string_sprintf("failed to expand helo_data: %s",
948 expand_string_message);
949 set_errno(addrlist, 0, message, DEFER, FALSE);
954 /** Debugging without sending a message
955 addrlist->transport_return = DEFER;
959 /* Errors that occur after this point follow an SMTP command, which is
960 left in big_buffer by smtp_write_command() for use in error messages. */
962 smtp_command = big_buffer;
964 /* Tell the remote who we are...
966 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
967 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
968 greeting is of this form. The assumption was that the far end supports it
969 properly... but experience shows that there are some that give 5xx responses,
970 even though the banner includes "ESMTP" (there's a bloody-minded one that
971 says "ESMTP not spoken here"). Cope with that case.
973 September 2000: Time has passed, and it seems reasonable now to always send
974 EHLO at the start. It is also convenient to make the change while installing
977 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
978 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
979 would be no way to send out the mails, so there is now a host list
980 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
981 PIPELINING problem as well. Maybe it can also be useful to cure other
982 problems with broken servers.
984 Exim originally sent "Helo" at this point and ran for nearly a year that way.
985 Then somebody tried it with a Microsoft mailer... It seems that all other
986 mailers use upper case for some reason (the RFC is quite clear about case
987 independence) so, for peace of mind, I gave in. */
989 esmtp = verify_check_this_host(&(ob->hosts_avoid_esmtp), NULL,
990 host->name, host->address, NULL) != OK;
994 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
995 lmtp? "LHLO" : "EHLO", helo_data) < 0)
997 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
998 ob->command_timeout))
1000 if (errno != 0 || buffer[0] == 0 || lmtp) goto RESPONSE_FAILED;
1007 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1012 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1014 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1015 ob->command_timeout)) goto RESPONSE_FAILED;
1018 /* Set IGNOREQUOTA if the response to LHLO specifies support and the
1019 lmtp_ignore_quota option was set. */
1021 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1022 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1023 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1025 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1028 tls_offered = esmtp &&
1029 pcre_exec(regex_STARTTLS, NULL, CS buffer, Ustrlen(buffer), 0,
1030 PCRE_EOPT, NULL, 0) >= 0;
1034 /* For continuing deliveries down the same channel, the socket is the standard
1035 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1036 below). Set up the pointer to where subsequent commands will be left, for
1037 error messages. Note that smtp_use_size and smtp_use_pipelining will have been
1038 set from the command line if they were set in the process that passed the
1043 inblock.sock = outblock.sock = fileno(stdin);
1044 smtp_command = big_buffer;
1045 host->port = port; /* Record the port that was used */
1048 /* If TLS is available on this connection, whether continued or not, attempt to
1049 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1050 send another EHLO - the server may give a different answer in secure mode. We
1051 use a separate buffer for reading the response to STARTTLS so that if it is
1052 negative, the original EHLO data is available for subsequent analysis, should
1053 the client not be required to use TLS. If the response is bad, copy the buffer
1054 for error analysis. */
1057 if (tls_offered && !suppress_tls &&
1058 verify_check_this_host(&(ob->hosts_avoid_tls), NULL, host->name,
1059 host->address, NULL) != OK)
1061 uschar buffer2[4096];
1062 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1065 /* If there is an I/O error, transmission of this message is deferred. If
1066 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1067 false, we also defer. However, if there is a temporary rejection of STARTTLS
1068 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1069 STARTTLS, we carry on. This means we will try to send the message in clear,
1070 unless the host is in hosts_require_tls (tested below). */
1072 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1073 ob->command_timeout))
1075 Ustrncpy(buffer, buffer2, sizeof(buffer));
1076 if (errno != 0 || buffer2[0] == 0 ||
1077 (buffer2[0] == '4' && !ob->tls_tempfail_tryclear))
1078 goto RESPONSE_FAILED;
1081 /* STARTTLS accepted: try to negotiate a TLS session. */
1085 int rc = tls_client_start(inblock.sock,
1088 NULL, /* No DH param */
1089 ob->tls_certificate,
1091 ob->tls_verify_certificates,
1093 ob->tls_require_ciphers,
1094 ob->gnutls_require_mac,
1095 ob->gnutls_require_kx,
1096 ob->gnutls_require_proto,
1097 ob->command_timeout);
1099 /* TLS negotiation failed; give an error. From outside, this function may
1100 be called again to try in clear on a new connection, if the options permit
1101 it for this host. */
1105 save_errno = ERRNO_TLSFAILURE;
1106 message = US"failure while setting up TLS session";
1111 /* TLS session is set up */
1113 for (addr = addrlist; addr != NULL; addr = addr->next)
1115 if (addr->transport_return == PENDING_DEFER)
1117 addr->cipher = tls_cipher;
1118 addr->peerdn = tls_peerdn;
1124 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1125 helo_data is null, we are dealing with a connection that was passed from
1126 another process, and so we won't have expanded helo_data above. We have to
1127 expand it here. $sending_ip_address and $sending_port are set up right at the
1128 start of the Exim process (in exim.c). */
1130 if (tls_active >= 0)
1132 if (helo_data == NULL)
1134 helo_data = expand_string(ob->helo_data);
1135 if (helo_data == NULL)
1137 uschar *message = string_sprintf("failed to expand helo_data: %s",
1138 expand_string_message);
1139 set_errno(addrlist, 0, message, DEFER, FALSE);
1145 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n", lmtp? "LHLO" : "EHLO",
1148 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1149 ob->command_timeout))
1150 goto RESPONSE_FAILED;
1153 /* If the host is required to use a secure channel, ensure that we
1156 else if (verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
1157 host->address, NULL) == OK)
1159 save_errno = ERRNO_TLSREQUIRED;
1160 message = string_sprintf("a TLS session is required for %s [%s], but %s",
1161 host->name, host->address,
1162 tls_offered? "an attempt to start TLS failed" :
1163 "the server did not offer TLS support");
1168 /* If TLS is active, we have just started it up and re-done the EHLO command,
1169 so its response needs to be analyzed. If TLS is not active and this is a
1170 continued session down a previously-used socket, we haven't just done EHLO, so
1173 if (continue_hostname == NULL
1180 uschar *fail_reason = US"server did not advertise AUTH support";
1182 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
1183 lmtp_ignore_quota option was set. */
1185 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1186 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1187 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1189 /* If the response to EHLO specified support for the SIZE parameter, note
1190 this, provided size_addition is non-negative. */
1192 smtp_use_size = esmtp && ob->size_addition >= 0 &&
1193 pcre_exec(regex_SIZE, NULL, CS buffer, Ustrlen(CS buffer), 0,
1194 PCRE_EOPT, NULL, 0) >= 0;
1196 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
1197 the current host, esmtp will be false, so PIPELINING can never be used. If
1198 the current host matches hosts_avoid_pipelining, don't do it. */
1200 smtp_use_pipelining = esmtp &&
1201 verify_check_this_host(&(ob->hosts_avoid_pipelining), NULL, host->name,
1202 host->address, NULL) != OK &&
1203 pcre_exec(regex_PIPELINING, NULL, CS buffer, Ustrlen(CS buffer), 0,
1204 PCRE_EOPT, NULL, 0) >= 0;
1206 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
1207 smtp_use_pipelining? "" : "not ");
1209 /* Note if the response to EHLO specifies support for the AUTH extension.
1210 If it has, check that this host is one we want to authenticate to, and do
1211 the business. The host name and address must be available when the
1212 authenticator's client driver is running. */
1214 smtp_authenticated = FALSE;
1215 require_auth = verify_check_this_host(&(ob->hosts_require_auth), NULL,
1216 host->name, host->address, NULL);
1218 if (esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
1220 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
1221 expand_nmax = -1; /* reset */
1223 /* Must not do this check until after we have saved the result of the
1224 regex match above. */
1226 if (require_auth == OK ||
1227 verify_check_this_host(&(ob->hosts_try_auth), NULL, host->name,
1228 host->address, NULL) == OK)
1231 fail_reason = US"no common mechanisms were found";
1233 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1235 /* Scan the configured authenticators looking for one which is configured
1236 for use as a client and whose name matches an authentication mechanism
1237 supported by the server. If one is found, attempt to authenticate by
1238 calling its client function. */
1240 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1243 if (!au->client) continue;
1245 /* Loop to scan supported server mechanisms */
1250 int len = Ustrlen(au->public_name);
1251 while (isspace(*p)) p++;
1253 if (strncmpic(au->public_name, p, len) != 0 ||
1254 (p[len] != 0 && !isspace(p[len])))
1256 while (*p != 0 && !isspace(*p)) p++;
1260 /* Found data for a listed mechanism. Call its client entry. Set
1261 a flag in the outblock so that data is overwritten after sending so
1262 that reflections don't show it. */
1264 fail_reason = US"authentication attempt(s) failed";
1265 outblock.authenticating = TRUE;
1266 rc = (au->info->clientcode)(au, &inblock, &outblock,
1267 ob->command_timeout, buffer, sizeof(buffer));
1268 outblock.authenticating = FALSE;
1269 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1272 /* A temporary authentication failure must hold up delivery to
1273 this host. After a permanent authentication failure, we carry on
1274 to try other authentication methods. If all fail hard, try to
1275 deliver the message unauthenticated unless require_auth was set. */
1280 smtp_authenticated = TRUE; /* stops the outer loop */
1283 /* Failure after writing a command */
1288 /* Failure after reading a response */
1291 if (errno != 0 || buffer[0] != '5') goto RESPONSE_FAILED;
1292 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1293 au->name, host->name, host->address, buffer);
1296 /* Failure by some other means. In effect, the authenticator
1297 decided it wasn't prepared to handle this case. Typically this
1298 is the result of "fail" in an expansion string. Do we need to
1299 log anything here? Feb 2006: a message is now put in the buffer
1300 if logging is required. */
1304 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1305 "authentication H=%s [%s] %s", au->name, host->name,
1306 host->address, buffer);
1309 /* Internal problem, message in buffer. */
1313 set_errno(addrlist, 0, string_copy(buffer), DEFER, FALSE);
1317 break; /* If not authenticated, try next authenticator */
1318 } /* Loop for scanning supported server mechanisms */
1319 } /* Loop for further authenticators */
1323 /* If we haven't authenticated, but are required to, give up. */
1325 if (require_auth == OK && !smtp_authenticated)
1328 set_errno(addrlist, ERRNO_AUTHFAIL,
1329 string_sprintf("authentication required but %s", fail_reason), DEFER,
1335 /* The setting up of the SMTP call is now complete. Any subsequent errors are
1336 message-specific. */
1340 /* If there is a filter command specified for this transport, we can now
1341 set it up. This cannot be done until the identify of the host is known. */
1343 if (tblock->filter_command != NULL)
1347 sprintf(CS buffer, "%.50s transport", tblock->name);
1348 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
1349 TRUE, DEFER, addrlist, buffer, NULL);
1351 /* On failure, copy the error to all addresses, abandon the SMTP call, and
1356 set_errno(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
1364 /* For messages that have more than the maximum number of envelope recipients,
1365 we want to send several transactions down the same SMTP connection. (See
1366 comments in deliver.c as to how this reconciles, heuristically, with
1367 remote_max_parallel.) This optimization was added to Exim after the following
1368 code was already working. The simplest way to put it in without disturbing the
1369 code was to use a goto to jump back to this point when there is another
1370 transaction to handle. */
1373 sync_addr = first_addr;
1377 completed_address = FALSE;
1380 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
1381 qualification, send it, adding something to the message size to allow for
1382 imprecision and things that get added en route. Exim keeps the number of lines
1383 in a message, so we can give an accurate value for the original message, but we
1384 need some additional to handle added headers. (Double "." characters don't get
1385 included in the count.) */
1392 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
1396 /* Add the authenticated sender address if present */
1398 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1399 local_authenticated_sender != NULL)
1401 string_format(p, sizeof(buffer) - (p-buffer), " AUTH=%s",
1402 auth_xtextencode(local_authenticated_sender,
1403 Ustrlen(local_authenticated_sender)));
1406 /* From here until we send the DATA command, we can make use of PIPELINING
1407 if the server host supports it. The code has to be able to check the responses
1408 at any point, for when the buffer fills up, so we write it totally generally.
1409 When PIPELINING is off, each command written reports that it has flushed the
1412 pending_MAIL = TRUE; /* The block starts with MAIL */
1414 rc = smtp_write_command(&outblock, smtp_use_pipelining,
1415 "MAIL FROM:<%s>%s\r\n", return_path, buffer);
1416 mail_command = string_copy(big_buffer); /* Save for later error message */
1420 case -1: /* Transmission error */
1423 case +1: /* Block was sent */
1424 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1425 ob->command_timeout))
1427 if (errno == 0 && buffer[0] == '4')
1429 errno = ERRNO_MAIL4XX;
1430 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1432 goto RESPONSE_FAILED;
1434 pending_MAIL = FALSE;
1438 /* Pass over all the relevant recipient addresses for this host, which are the
1439 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
1440 several before we have to read the responses for those seen so far. This
1441 checking is done by a subroutine because it also needs to be done at the end.
1442 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
1443 the next one if not all are sent.
1445 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
1446 last address because we want to abort if any recipients have any kind of
1447 problem, temporary or permanent. We know that all recipient addresses will have
1448 the PENDING_DEFER status, because only one attempt is ever made, and we know
1449 that max_rcpt will be large, so all addresses will be done at once. */
1451 for (addr = first_addr;
1452 address_count < max_rcpt && addr != NULL;
1458 if (addr->transport_return != PENDING_DEFER) continue;
1461 no_flush = smtp_use_pipelining && (!mua_wrapper || addr->next != NULL);
1463 /* Now send the RCPT command, and process outstanding responses when
1464 necessary. After a timeout on RCPT, we just end the function, leaving the
1465 yield as OK, because this error can often mean that there is a problem with
1466 just one address, so we don't want to delay the host. */
1468 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s\r\n",
1469 transport_rcpt_address(addr, tblock->rcpt_include_affixes), igquotstr);
1470 if (count < 0) goto SEND_FAILED;
1473 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
1474 &sync_addr, host, count, ob->address_retry_include_sender,
1475 pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
1478 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1479 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1482 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1483 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1484 case 0: /* No 2xx or 5xx, but no probs */
1487 case -1: goto END_OFF; /* Timeout on RCPT */
1488 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
1490 pending_MAIL = FALSE; /* Dealt with MAIL */
1492 } /* Loop for next address */
1494 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
1495 permanently or temporarily. We should have flushed and synced after the last
1500 address_item *badaddr;
1501 for (badaddr = first_addr; badaddr != NULL; badaddr = badaddr->next)
1503 if (badaddr->transport_return != PENDING_OK) break;
1505 if (badaddr != NULL)
1507 set_errno(addrlist, 0, badaddr->message, FAIL,
1508 testflag(badaddr, af_pass_message));
1513 /* If ok is TRUE, we know we have got at least one good recipient, and must now
1514 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
1515 have a good recipient buffered up if we are pipelining. We don't want to waste
1516 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
1517 are pipelining. The responses are all handled by sync_responses(). */
1519 if (ok || (smtp_use_pipelining && !mua_wrapper))
1521 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
1522 if (count < 0) goto SEND_FAILED;
1523 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
1524 host, count, ob->address_retry_include_sender, pending_MAIL,
1525 ok? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
1527 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1528 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1531 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1532 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1533 case 0: break; /* No 2xx or 5xx, but no probs */
1535 case -1: goto END_OFF; /* Timeout on RCPT */
1536 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
1540 /* Save the first address of the next batch. */
1544 /* If there were no good recipients (but otherwise there have been no
1545 problems), just set ok TRUE, since we have handled address-specific errors
1546 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
1547 for handling the SMTP dot-handling protocol, flagging to apply to headers as
1548 well as body. Set the appropriate timeout value to be used for each chunk.
1549 (Haven't been able to make it work using select() for writing yet.) */
1551 if (!ok) ok = TRUE; else
1553 sigalrm_seen = FALSE;
1554 transport_write_timeout = ob->data_timeout;
1555 smtp_command = US"sending data block"; /* For error messages */
1556 DEBUG(D_transport|D_v)
1557 debug_printf(" SMTP>> writing message and terminating \".\"\n");
1558 transport_count = 0;
1559 #ifdef EXPERIMENTAL_DOMAINKEYS
1560 if ( (ob->dk_private_key != NULL) && (ob->dk_selector != NULL) )
1561 ok = dk_transport_write_message(addrlist, inblock.sock,
1562 topt_use_crlf | topt_end_dot | topt_escape_headers |
1563 (tblock->body_only? topt_no_headers : 0) |
1564 (tblock->headers_only? topt_no_body : 0) |
1565 (tblock->return_path_add? topt_add_return_path : 0) |
1566 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1567 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1568 0, /* No size limit */
1569 tblock->add_headers, tblock->remove_headers,
1570 US".", US"..", /* Escaping strings */
1571 tblock->rewrite_rules, tblock->rewrite_existflags,
1572 ob->dk_private_key, ob->dk_domain, ob->dk_selector,
1573 ob->dk_canon, ob->dk_headers, ob->dk_strict);
1576 ok = transport_write_message(addrlist, inblock.sock,
1577 topt_use_crlf | topt_end_dot | topt_escape_headers |
1578 (tblock->body_only? topt_no_headers : 0) |
1579 (tblock->headers_only? topt_no_body : 0) |
1580 (tblock->return_path_add? topt_add_return_path : 0) |
1581 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1582 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1583 0, /* No size limit */
1584 tblock->add_headers, tblock->remove_headers,
1585 US".", US"..", /* Escaping strings */
1586 tblock->rewrite_rules, tblock->rewrite_existflags);
1588 /* transport_write_message() uses write() because it is called from other
1589 places to write to non-sockets. This means that under some OS (e.g. Solaris)
1590 it can exit with "Broken pipe" as its error. This really means that the
1591 socket got closed at the far end. */
1593 transport_write_timeout = 0; /* for subsequent transports */
1595 /* Failure can either be some kind of I/O disaster (including timeout),
1596 or the failure of a transport filter or the expansion of added headers. */
1600 buffer[0] = 0; /* There hasn't been a response */
1601 goto RESPONSE_FAILED;
1604 /* We used to send the terminating "." explicitly here, but because of
1605 buffering effects at both ends of TCP/IP connections, you don't gain
1606 anything by keeping it separate, so it might as well go in the final
1607 data buffer for efficiency. This is now done by setting the topt_end_dot
1610 smtp_command = US"end of data";
1612 /* For SMTP, we now read a single response that applies to the whole message.
1613 If it is OK, then all the addresses have been delivered. */
1617 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1619 if (!ok && errno == 0 && buffer[0] == '4')
1621 errno = ERRNO_DATA4XX;
1622 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1626 /* For LMTP, we get back a response for every RCPT command that we sent;
1627 some may be accepted and some rejected. For those that get a response, their
1628 status is fixed; any that are accepted have been handed over, even if later
1629 responses crash - at least, that's how I read RFC 2033.
1631 If all went well, mark the recipient addresses as completed, record which
1632 host/IPaddress they were delivered to, and cut out RSET when sending another
1633 message down the same channel. Write the completed addresses to the journal
1634 now so that they are recorded in case there is a crash of hardware or
1635 software before the spool gets updated. Also record the final SMTP
1636 confirmation if needed (for SMTP only). */
1641 int delivery_time = (int)(time(NULL) - start_delivery_time);
1644 uschar *conf = NULL;
1647 /* Make a copy of the host if it is local to this invocation
1648 of the transport. */
1652 thost = store_get(sizeof(host_item));
1654 thost->name = string_copy(host->name);
1655 thost->address = string_copy(host->address);
1659 /* Set up confirmation if needed - applies only to SMTP */
1661 if ((log_extra_selector & LX_smtp_confirmation) != 0 && !lmtp)
1663 uschar *s = string_printing(buffer);
1664 conf = (s == buffer)? (uschar *)string_copy(s) : s;
1667 /* Process all transported addresses - for LMTP, read a status for
1670 for (addr = addrlist; addr != first_addr; addr = addr->next)
1672 if (addr->transport_return != PENDING_OK) continue;
1674 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
1675 remaining addresses. Otherwise, it's a return code for just the one
1676 address. For temporary errors, add a retry item for the address so that
1677 it doesn't get tried again too soon. */
1681 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1684 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
1685 addr->message = string_sprintf("LMTP error after %s: %s",
1686 big_buffer, string_printing(buffer));
1687 setflag(addr, af_pass_message); /* Allow message to go to user */
1688 if (buffer[0] == '5')
1689 addr->transport_return = FAIL;
1692 errno = ERRNO_DATA4XX;
1693 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1694 addr->transport_return = DEFER;
1695 retry_add_item(addr, addr->address_retry_key, 0);
1699 completed_address = TRUE; /* NOW we can set this flag */
1702 /* SMTP, or success return from LMTP for this address. Pass back the
1703 actual host that was used. */
1705 addr->transport_return = OK;
1706 addr->more_errno = delivery_time;
1707 addr->host_used = thost;
1708 addr->special_action = flag;
1709 addr->message = conf;
1712 /* Update the journal. For homonymic addresses, use the base address plus
1713 the transport name. See lots of comments in deliver.c about the reasons
1714 for the complications when homonyms are involved. Just carry on after
1715 write error, as it may prove possible to update the spool file later. */
1717 if (testflag(addr, af_homonym))
1718 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
1720 sprintf(CS buffer, "%.500s\n", addr->unique);
1722 DEBUG(D_deliver) debug_printf("journalling %s", buffer);
1723 len = Ustrlen(CS buffer);
1724 if (write(journal_fd, buffer, len) != len)
1725 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
1726 "%s: %s", buffer, strerror(errno));
1729 /* Ensure the journal file is pushed out to disk. */
1731 if (EXIMfsync(journal_fd) < 0)
1732 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
1738 /* Handle general (not specific to one address) failures here. The value of ok
1739 is used to skip over this code on the falling through case. A timeout causes a
1740 deferral. Other errors may defer or fail according to the response code, and
1741 may set up a special errno value, e.g. after connection chopped, which is
1742 assumed if errno == 0 and there is no text in the buffer. If control reaches
1743 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
1744 the problem is not related to this specific message. */
1753 send_quit = check_response(host, &save_errno, addrlist->more_errno,
1754 buffer, &code, &message, &pass_message);
1760 message = US string_sprintf("send() to %s [%s] failed: %s",
1761 host->name, host->address, strerror(save_errno));
1765 /* This label is jumped to directly when a TLS negotiation has failed,
1766 or was not done for a host for which it is required. Values will be set
1767 in message and save_errno, and setting_up will always be true. Treat as
1768 a temporary error. */
1775 /* If the failure happened while setting up the call, see if the failure was
1776 a 5xx response (this will either be on connection, or following HELO - a 5xx
1777 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
1778 never going to accept them. For other errors during setting up (timeouts or
1779 whatever), defer all addresses, and yield DEFER, so that the host is not
1780 tried again for a while. */
1783 ok = FALSE; /* For when reached by GOTO */
1789 set_errno(addrlist, save_errno, message, FAIL, pass_message);
1793 set_errno(addrlist, save_errno, message, DEFER, pass_message);
1798 /* We want to handle timeouts after MAIL or "." and loss of connection after
1799 "." specially. They can indicate a problem with the sender address or with
1800 the contents of the message rather than a real error on the connection. These
1801 cases are treated in the same way as a 4xx response. This next bit of code
1802 does the classification. */
1813 message_error = TRUE;
1817 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
1818 Ustrncmp(smtp_command,"end ",4) == 0;
1821 case ERRNO_SMTPCLOSED:
1822 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
1826 message_error = FALSE;
1830 /* Handle the cases that are treated as message errors. These are:
1832 (a) negative response or timeout after MAIL
1833 (b) negative response after DATA
1834 (c) negative response or timeout or dropped connection after "."
1836 It won't be a negative response or timeout after RCPT, as that is dealt
1837 with separately above. The action in all cases is to set an appropriate
1838 error code for all the addresses, but to leave yield set to OK because the
1839 host itself has not failed. Of course, it might in practice have failed
1840 when we've had a timeout, but if so, we'll discover that at the next
1841 delivery attempt. For a temporary error, set the message_defer flag, and
1842 write to the logs for information if this is not the last host. The error
1843 for the last host will be logged as part of the address's log line. */
1847 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
1848 set_errno(addrlist, save_errno, message, (code == '5')? FAIL : DEFER,
1851 /* If there's an errno, the message contains just the identity of
1854 if (code != '5') /* Anything other than 5 is treated as temporary */
1857 message = US string_sprintf("%s: %s", message, strerror(save_errno));
1858 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
1859 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
1860 *message_defer = TRUE;
1864 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
1865 ".", or some other transportation error. We defer all addresses and yield
1866 DEFER, except for the case of failed add_headers expansion, or a transport
1867 filter failure, when the yield should be ERROR, to stop it trying other
1872 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
1873 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
1874 set_errno(addrlist, save_errno, message, DEFER, pass_message);
1880 /* If all has gone well, send_quit will be set TRUE, implying we can end the
1881 SMTP session tidily. However, if there were too many addresses to send in one
1882 message (indicated by first_addr being non-NULL) we want to carry on with the
1883 rest of them. Also, it is desirable to send more than one message down the SMTP
1884 connection if there are several waiting, provided we haven't already sent so
1885 many as to hit the configured limit. The function transport_check_waiting looks
1886 for a waiting message and returns its id. Then transport_pass_socket tries to
1887 set up a continued delivery by passing the socket on to another process. The
1888 variable send_rset is FALSE if a message has just been successfully transfered.
1890 If we are already sending down a continued channel, there may be further
1891 addresses not yet delivered that are aimed at the same host, but which have not
1892 been passed in this run of the transport. In this case, continue_more will be
1893 true, and all we should do is send RSET if necessary, and return, leaving the
1896 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
1897 do not want to continue with other messages down the same channel, because that
1898 can lead to looping between two or more messages, all with the same,
1899 temporarily failing address(es). [The retry information isn't updated yet, so
1900 new processes keep on trying.] We probably also don't want to try more of this
1901 message's addresses either.
1903 If we have started a TLS session, we have to end it before passing the
1904 connection to a new process. However, not all servers can handle this (Exim
1905 can), so we do not pass such a connection on if the host matches
1906 hosts_nopass_tls. */
1909 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
1910 "yield=%d first_address is %sNULL\n", ok, send_quit, send_rset,
1911 continue_more, yield, (first_addr == NULL)? "":"not ");
1913 if (completed_address && ok && send_quit)
1916 if (first_addr != NULL || continue_more ||
1919 verify_check_this_host(&(ob->hosts_nopass_tls), NULL, host->name,
1920 host->address, NULL) != OK)
1922 transport_check_waiting(tblock->name, host->name,
1923 tblock->connection_max_messages, new_message_id, &more)
1931 if (! (ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
1933 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
1934 host->address, strerror(save_errno));
1937 else if (! (ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1938 ob->command_timeout)))
1941 send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
1945 DEBUG(D_transport) debug_printf("%s\n", msg);
1950 /* Either RSET was not needed, or it succeeded */
1954 if (first_addr != NULL) /* More addresses still to be sent */
1955 { /* in this run of the transport */
1956 continue_sequence++; /* Causes * in logging */
1959 if (continue_more) return yield; /* More addresses for another run */
1961 /* Pass the socket to a new Exim process. Before doing so, we must shut
1962 down TLS. Not all MTAs allow for the continuation of the SMTP session
1963 when TLS is shut down. We test for this by sending a new EHLO. If we
1964 don't get a good response, we don't attempt to pass the socket on. */
1967 if (tls_active >= 0)
1970 ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
1971 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1972 ob->command_timeout);
1976 /* If the socket is successfully passed, we musn't send QUIT (or
1977 indeed anything!) from here. */
1979 if (ok && transport_pass_socket(tblock->name, host->name, host->address,
1980 new_message_id, inblock.sock))
1986 /* If RSET failed and there are addresses left, they get deferred. */
1988 else set_errno(first_addr, errno, msg, DEFER, FALSE);
1992 /* End off tidily with QUIT unless the connection has died or the socket has
1993 been passed to another process. There has been discussion on the net about what
1994 to do after sending QUIT. The wording of the RFC suggests that it is necessary
1995 to wait for a response, but on the other hand, there isn't anything one can do
1996 with an error response, other than log it. Exim used to do that. However,
1997 further discussion suggested that it is positively advantageous not to wait for
1998 the response, but to close the session immediately. This is supposed to move
1999 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
2000 load from the server. (Hosts that are both servers and clients may not see much
2001 difference, of course.) Further discussion indicated that this was safe to do
2002 on Unix systems which have decent implementations of TCP/IP that leave the
2003 connection around for a while (TIME_WAIT) after the application has gone away.
2004 This enables the response sent by the server to be properly ACKed rather than
2005 timed out, as can happen on broken TCP/IP implementations on other OS.
2007 This change is being made on 31-Jul-98. After over a year of trouble-free
2008 operation, the old commented-out code was removed on 17-Sep-99. */
2011 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2019 /* Close the socket, and return the appropriate value, first setting
2020 continue_transport and continue_hostname NULL to prevent any other addresses
2021 that may include the host from trying to re-use a continuation socket. This
2022 works because the NULL setting is passed back to the calling process, and
2023 remote_max_parallel is forced to 1 when delivering over an existing connection,
2025 If all went well and continue_more is set, we shouldn't actually get here if
2026 there are further addresses, as the return above will be taken. However,
2027 writing RSET might have failed, or there may be other addresses whose hosts are
2028 specified in the transports, and therefore not visible at top level, in which
2029 case continue_more won't get set. */
2031 (void)close(inblock.sock);
2032 continue_transport = NULL;
2033 continue_hostname = NULL;
2040 /*************************************************
2041 * Closedown entry point *
2042 *************************************************/
2044 /* This function is called when exim is passed an open smtp channel
2045 from another incarnation, but the message which it has been asked
2046 to deliver no longer exists. The channel is on stdin.
2048 We might do fancy things like looking for another message to send down
2049 the channel, but if the one we sought has gone, it has probably been
2050 delivered by some other process that itself will seek further messages,
2051 so just close down our connection.
2053 Argument: pointer to the transport instance block
2058 smtp_transport_closedown(transport_instance *tblock)
2060 smtp_transport_options_block *ob =
2061 (smtp_transport_options_block *)(tblock->options_block);
2062 smtp_inblock inblock;
2063 smtp_outblock outblock;
2065 uschar inbuffer[4096];
2066 uschar outbuffer[16];
2068 inblock.sock = fileno(stdin);
2069 inblock.buffer = inbuffer;
2070 inblock.buffersize = sizeof(inbuffer);
2071 inblock.ptr = inbuffer;
2072 inblock.ptrend = inbuffer;
2074 outblock.sock = inblock.sock;
2075 outblock.buffersize = sizeof(outbuffer);
2076 outblock.buffer = outbuffer;
2077 outblock.ptr = outbuffer;
2078 outblock.cmd_count = 0;
2079 outblock.authenticating = FALSE;
2081 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2082 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2083 ob->command_timeout);
2084 (void)close(inblock.sock);
2089 /*************************************************
2090 * Prepare addresses for delivery *
2091 *************************************************/
2093 /* This function is called to flush out error settings from previous delivery
2094 attempts to other hosts. It also records whether we got here via an MX record
2095 or not in the more_errno field of the address. We are interested only in
2096 addresses that are still marked DEFER - others may have got delivered to a
2097 previously considered IP address. Set their status to PENDING_DEFER to indicate
2098 which ones are relevant this time.
2101 addrlist the list of addresses
2102 host the host we are delivering to
2104 Returns: the first address for this delivery
2107 static address_item *
2108 prepare_addresses(address_item *addrlist, host_item *host)
2110 address_item *first_addr = NULL;
2112 for (addr = addrlist; addr != NULL; addr = addr->next)
2114 if (addr->transport_return != DEFER) continue;
2115 if (first_addr == NULL) first_addr = addr;
2116 addr->transport_return = PENDING_DEFER;
2117 addr->basic_errno = 0;
2118 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
2119 addr->message = NULL;
2121 addr->cipher = NULL;
2122 addr->peerdn = NULL;
2130 /*************************************************
2131 * Main entry point *
2132 *************************************************/
2134 /* See local README for interface details. As this is a remote transport, it is
2135 given a chain of addresses to be delivered in one connection, if possible. It
2136 always returns TRUE, indicating that each address has its own independent
2137 status set, except if there is a setting up problem, in which case it returns
2141 smtp_transport_entry(
2142 transport_instance *tblock, /* data for this instantiation */
2143 address_item *addrlist) /* addresses we are working on */
2147 int hosts_defer = 0;
2149 int hosts_looked_up = 0;
2150 int hosts_retry = 0;
2151 int hosts_serial = 0;
2152 int hosts_total = 0;
2153 int total_hosts_tried = 0;
2155 BOOL expired = TRUE;
2156 BOOL continuing = continue_hostname != NULL;
2157 uschar *expanded_hosts = NULL;
2159 uschar *tid = string_sprintf("%s transport", tblock->name);
2160 smtp_transport_options_block *ob =
2161 (smtp_transport_options_block *)(tblock->options_block);
2162 host_item *hostlist = addrlist->host_list;
2163 host_item *host = NULL;
2167 debug_printf("%s transport entered\n", tblock->name);
2168 for (addr = addrlist; addr != NULL; addr = addr->next)
2169 debug_printf(" %s\n", addr->address);
2170 if (continuing) debug_printf("already connected to %s [%s]\n",
2171 continue_hostname, continue_host_address);
2174 /* Set the flag requesting that these hosts be added to the waiting
2175 database if the delivery fails temporarily or if we are running with
2176 queue_smtp or a 2-stage queue run. This gets unset for certain
2177 kinds of error, typically those that are specific to the message. */
2179 update_waiting = TRUE;
2181 /* If a host list is not defined for the addresses - they must all have the
2182 same one in order to be passed to a single transport - or if the transport has
2183 a host list with hosts_override set, use the host list supplied with the
2184 transport. It is an error for this not to exist. */
2186 if (hostlist == NULL || (ob->hosts_override && ob->hosts != NULL))
2188 if (ob->hosts == NULL)
2190 addrlist->message = string_sprintf("%s transport called with no hosts set",
2192 addrlist->transport_return = PANIC;
2193 return FALSE; /* Only top address has status */
2196 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
2199 /* If the transport's host list contains no '$' characters, and we are not
2200 randomizing, it is fixed and therefore a chain of hosts can be built once
2201 and for all, and remembered for subsequent use by other calls to this
2202 transport. If, on the other hand, the host list does contain '$', or we are
2203 randomizing its order, we have to rebuild it each time. In the fixed case,
2204 as the hosts string will never be used again, it doesn't matter that we
2205 replace all the : characters with zeros. */
2207 if (ob->hostlist == NULL)
2209 uschar *s = ob->hosts;
2211 if (Ustrchr(s, '$') != NULL)
2213 expanded_hosts = expand_string(s);
2214 if (expanded_hosts == NULL)
2216 addrlist->message = string_sprintf("failed to expand list of hosts "
2217 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
2218 addrlist->transport_return = search_find_defer? DEFER : PANIC;
2219 return FALSE; /* Only top address has status */
2221 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
2222 "\"%s\"\n", s, expanded_hosts);
2226 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
2228 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
2230 /* If there was no expansion of hosts, save the host list for
2233 if (expanded_hosts == NULL) ob->hostlist = hostlist;
2236 /* This is not the first time this transport has been run in this delivery;
2237 the host list was built previously. */
2239 else hostlist = ob->hostlist;
2242 /* The host list was supplied with the address. If hosts_randomize is set, we
2243 must sort it into a random order if it did not come from MX records and has not
2244 already been randomized (but don't bother if continuing down an existing
2247 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continuing)
2249 host_item *newlist = NULL;
2250 while (hostlist != NULL)
2252 host_item *h = hostlist;
2253 hostlist = hostlist->next;
2255 h->sort_key = random_number(100);
2257 if (newlist == NULL)
2262 else if (h->sort_key < newlist->sort_key)
2269 host_item *hh = newlist;
2270 while (hh->next != NULL)
2272 if (h->sort_key < hh->next->sort_key) break;
2280 hostlist = addrlist->host_list = newlist;
2284 /* Sort out the default port. */
2286 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
2289 /* For each host-plus-IP-address on the list:
2291 . If this is a continued delivery and the host isn't the one with the
2292 current connection, skip.
2294 . If the status is unusable (i.e. previously failed or retry checked), skip.
2296 . If no IP address set, get the address, either by turning the name into
2297 an address, calling gethostbyname if gethostbyname is on, or by calling
2298 the DNS. The DNS may yield multiple addresses, in which case insert the
2299 extra ones into the list.
2301 . Get the retry data if not previously obtained for this address and set the
2302 field which remembers the state of this address. Skip if the retry time is
2303 not reached. If not, remember whether retry data was found. The retry string
2304 contains both the name and the IP address.
2306 . Scan the list of addresses and mark those whose status is DEFER as
2307 PENDING_DEFER. These are the only ones that will be processed in this cycle
2310 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
2311 Some addresses may be successfully delivered, others may fail, and yet
2312 others may get temporary errors and so get marked DEFER.
2314 . The return from the delivery attempt is OK if a connection was made and a
2315 valid SMTP dialogue was completed. Otherwise it is DEFER.
2317 . If OK, add a "remove" retry item for this host/IPaddress, if any.
2319 . If fail to connect, or other defer state, add a retry item.
2321 . If there are any addresses whose status is still DEFER, carry on to the
2322 next host/IPaddress, unless we have tried the number of hosts given
2323 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
2324 there is some fancy logic for hosts_max_try that means its limit can be
2325 overstepped in some circumstances.
2327 If we get to the end of the list, all hosts have deferred at least one address,
2328 or not reached their retry times. If delay_after_cutoff is unset, it requests a
2329 delivery attempt to those hosts whose last try was before the arrival time of
2330 the current message. To cope with this, we have to go round the loop a second
2331 time. After that, set the status and error data for any addresses that haven't
2332 had it set already. */
2334 for (cutoff_retry = 0; expired &&
2335 cutoff_retry < ((ob->delay_after_cutoff)? 1 : 2);
2338 host_item *nexthost = NULL;
2339 int unexpired_hosts_tried = 0;
2341 for (host = hostlist;
2343 unexpired_hosts_tried < ob->hosts_max_try &&
2344 total_hosts_tried < ob->hosts_max_try_hardlimit;
2350 BOOL serialized = FALSE;
2351 BOOL host_is_expired = FALSE;
2352 BOOL message_defer = FALSE;
2353 BOOL ifchanges = FALSE;
2354 BOOL some_deferred = FALSE;
2355 address_item *first_addr = NULL;
2356 uschar *interface = NULL;
2357 uschar *retry_host_key = NULL;
2358 uschar *retry_message_key = NULL;
2359 uschar *serialize_key = NULL;
2361 /* Default next host is next host. :-) But this can vary if the
2362 hosts_max_try limit is hit (see below). It may also be reset if a host
2363 address is looked up here (in case the host was multihomed). */
2365 nexthost = host->next;
2367 /* If the address hasn't yet been obtained from the host name, look it up
2368 now, unless the host is already marked as unusable. If it is marked as
2369 unusable, it means that the router was unable to find its IP address (in
2370 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
2371 the lookup failed last time. We don't get this far if *all* MX records
2372 point to non-existent hosts; that is treated as a hard error.
2374 We can just skip this host entirely. When the hosts came from the router,
2375 the address will timeout based on the other host(s); when the address is
2376 looked up below, there is an explicit retry record added.
2378 Note that we mustn't skip unusable hosts if the address is not unset; they
2379 may be needed as expired hosts on the 2nd time round the cutoff loop. */
2381 if (host->address == NULL)
2383 int new_port, flags;
2385 uschar *canonical_name;
2387 if (host->status >= hstatus_unusable)
2389 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
2394 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
2396 /* The host name is permitted to have an attached port. Find it, and
2397 strip it from the name. Just remember it for now. */
2399 new_port = host_item_get_port(host);
2401 /* Count hosts looked up */
2405 /* Find by name if so configured, or if it's an IP address. We don't
2406 just copy the IP address, because we need the test-for-local to happen. */
2408 flags = HOST_FIND_BY_A;
2409 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
2410 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
2412 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
2413 rc = host_find_byname(host, NULL, flags, &canonical_name, TRUE);
2415 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
2416 &canonical_name, NULL);
2418 /* Update the host (and any additional blocks, resulting from
2419 multihoming) with a host-specific port, if any. */
2421 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
2423 /* Failure to find the host at this time (usually DNS temporary failure)
2424 is really a kind of routing failure rather than a transport failure.
2425 Therefore we add a retry item of the routing kind, not to stop us trying
2426 to look this name up here again, but to ensure the address gets timed
2427 out if the failures go on long enough. A complete failure at this point
2428 commonly points to a configuration error, but the best action is still
2429 to carry on for the next host. */
2431 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
2433 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
2435 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
2436 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
2437 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
2438 host->status = hstatus_unusable;
2440 for (addr = addrlist; addr != NULL; addr = addr->next)
2442 if (addr->transport_return != DEFER) continue;
2443 addr->basic_errno = ERRNO_UNKNOWNHOST;
2445 string_sprintf("failed to lookup IP address for %s", host->name);
2450 /* If the host is actually the local host, we may have a problem, or
2451 there may be some cunning configuration going on. In the problem case,
2452 log things and give up. The default transport status is already DEFER. */
2454 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
2456 for (addr = addrlist; addr != NULL; addr = addr->next)
2458 addr->basic_errno = 0;
2459 addr->message = string_sprintf("%s transport found host %s to be "
2460 "local", tblock->name, host->name);
2464 } /* End of block for IP address lookup */
2466 /* If this is a continued delivery, we are interested only in the host
2467 which matches the name of the existing open channel. The check is put
2468 here after the local host lookup, in case the name gets expanded as a
2469 result of the lookup. Set expired FALSE, to save the outer loop executing
2472 if (continuing && (Ustrcmp(continue_hostname, host->name) != 0 ||
2473 Ustrcmp(continue_host_address, host->address) != 0))
2476 continue; /* With next host */
2479 /* Reset the default next host in case a multihomed host whose addresses
2480 are not looked up till just above added to the host list. */
2482 nexthost = host->next;
2484 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
2485 domain is in queue_smtp_domains, we don't actually want to attempt any
2486 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
2487 there is a lookup defer in queue_smtp_domains, proceed as if the domain
2488 were not in it. We don't want to hold up all SMTP deliveries! Except when
2489 doing a two-stage queue run, don't do this if forcing. */
2491 if ((!deliver_force || queue_2stage) && (queue_smtp ||
2492 match_isinlist(addrlist->domain, &queue_smtp_domains, 0,
2493 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
2496 for (addr = addrlist; addr != NULL; addr = addr->next)
2498 if (addr->transport_return != DEFER) continue;
2499 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
2501 continue; /* With next host */
2504 /* Count hosts being considered - purely for an intelligent comment
2505 if none are usable. */
2509 /* Set $host and $host address now in case they are needed for the
2510 interface expansion or the serialize_hosts check; they remain set if an
2511 actual delivery happens. */
2513 deliver_host = host->name;
2514 deliver_host_address = host->address;
2516 /* Set up a string for adding to the retry key if the port number is not
2517 the standard SMTP port. A host may have its own port setting that overrides
2520 pistring = string_sprintf(":%d", (host->port == PORT_NONE)?
2522 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
2524 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
2525 string changes upon expansion, we must add it to the key that is used for
2526 retries, because connections to the same host from a different interface
2527 should be treated separately. */
2529 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET : AF_INET6;
2530 if (!smtp_get_interface(ob->interface, host_af, addrlist, &ifchanges,
2533 if (ifchanges) pistring = string_sprintf("%s/%s", pistring, interface);
2535 /* The first time round the outer loop, check the status of the host by
2536 inspecting the retry data. The second time round, we are interested only
2537 in expired hosts that haven't been tried since this message arrived. */
2539 if (cutoff_retry == 0)
2541 /* Ensure the status of the address is set by checking retry data if
2542 necessary. There maybe host-specific retry data (applicable to all
2543 messages) and also data for retries of a specific message at this host.
2544 If either of these retry records are actually read, the keys used are
2545 returned to save recomputing them later. */
2547 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
2548 ob->retry_include_ip_address, &retry_host_key, &retry_message_key);
2550 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
2551 (host->address == NULL)? US"" : host->address, pistring,
2552 (host->status == hstatus_usable)? "usable" :
2553 (host->status == hstatus_unusable)? "unusable" :
2554 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
2556 /* Skip this address if not usable at this time, noting if it wasn't
2557 actually expired, both locally and in the address. */
2559 switch (host->status)
2561 case hstatus_unusable:
2563 setflag(addrlist, af_retry_skipped);
2566 case hstatus_unusable_expired:
2569 case hwhy_retry: hosts_retry++; break;
2570 case hwhy_failed: hosts_fail++; break;
2571 case hwhy_deferred: hosts_defer++; break;
2574 /* If there was a retry message key, implying that previously there
2575 was a message-specific defer, we don't want to update the list of
2576 messages waiting for these hosts. */
2578 if (retry_message_key != NULL) update_waiting = FALSE;
2579 continue; /* With the next host or IP address */
2583 /* Second time round the loop: if the address is set but expired, and
2584 the message is newer than the last try, let it through. */
2588 if (host->address == NULL ||
2589 host->status != hstatus_unusable_expired ||
2590 host->last_try > received_time)
2593 debug_printf("trying expired host %s [%s]%s\n",
2594 host->name, host->address, pistring);
2595 host_is_expired = TRUE;
2598 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
2599 it remains TRUE only if all hosts are expired and none are actually tried.
2604 /* If this host is listed as one to which access must be serialized,
2605 see if another Exim process has a connection to it, and if so, skip
2606 this host. If not, update the database to record our connection to it
2607 and remember this for later deletion. Do not do any of this if we are
2608 sending the message down a pre-existing connection. */
2611 verify_check_this_host(&(ob->serialize_hosts), NULL, host->name,
2612 host->address, NULL) == OK)
2614 serialize_key = string_sprintf("host-serialize-%s", host->name);
2615 if (!enq_start(serialize_key))
2618 debug_printf("skipping host %s because another Exim process "
2619 "is connected to it\n", host->name);
2626 /* OK, we have an IP address that is not waiting for its retry time to
2627 arrive (it might be expired) OR (second time round the loop) we have an
2628 expired host that hasn't been tried since the message arrived. Have a go
2629 at delivering the message to it. First prepare the addresses by flushing
2630 out the result of previous attempts, and finding the first address that
2631 is still to be delivered. */
2633 first_addr = prepare_addresses(addrlist, host);
2635 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
2636 message_id, host->name, host->address, addrlist->address,
2637 (addrlist->next == NULL)? "" : ", ...");
2639 set_process_info("delivering %s to %s [%s] (%s%s)",
2640 message_id, host->name, host->address, addrlist->address,
2641 (addrlist->next == NULL)? "" : ", ...");
2643 /* This is not for real; don't do the delivery. If there are
2644 any remaining hosts, list them. */
2649 set_errno(addrlist, 0, NULL, OK, FALSE);
2650 for (addr = addrlist; addr != NULL; addr = addr->next)
2652 addr->host_used = host;
2653 addr->special_action = '*';
2654 addr->message = US"delivery bypassed by -N option";
2658 debug_printf("*** delivery by %s transport bypassed by -N option\n"
2659 "*** host and remaining hosts:\n", tblock->name);
2660 for (host2 = host; host2 != NULL; host2 = host2->next)
2661 debug_printf(" %s [%s]\n", host2->name,
2662 (host2->address == NULL)? US"unset" : host2->address);
2667 /* This is for real. If the host is expired, we don't count it for
2668 hosts_max_retry. This ensures that all hosts must expire before an address
2669 is timed out, unless hosts_max_try_hardlimit (which protects against
2670 lunatic DNS configurations) is reached.
2672 If the host is not expired and we are about to hit the hosts_max_retry
2673 limit, check to see if there is a subsequent hosts with a different MX
2674 value. If so, make that the next host, and don't count this one. This is a
2675 heuristic to make sure that different MXs do get tried. With a normal kind
2676 of retry rule, they would get tried anyway when the earlier hosts were
2677 delayed, but if the domain has a "retry every time" type of rule - as is
2678 often used for the the very large ISPs, that won't happen. */
2682 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
2686 debug_printf("hosts_max_try limit reached with this host\n");
2687 for (h = host; h != NULL; h = h->next)
2688 if (h->mx != host->mx) break;
2692 unexpired_hosts_tried--;
2693 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
2694 "and will be tried\n");
2698 /* Attempt the delivery. */
2700 total_hosts_tried++;
2701 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
2702 expanded_hosts != NULL, &message_defer, FALSE);
2705 OK => connection made, each address contains its result;
2706 message_defer is set for message-specific defers (when all
2707 recipients are marked defer)
2708 DEFER => there was a non-message-specific delivery problem;
2709 ERROR => there was a problem setting up the arguments for a filter,
2710 or there was a problem with expanding added headers
2713 /* If the result is not OK, there was a non-message-specific problem.
2714 If the result is DEFER, we need to write to the logs saying what happened
2715 for this particular host, except in the case of authentication and TLS
2716 failures, where the log has already been written. If all hosts defer a
2717 general message is written at the end. */
2719 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL &&
2720 first_addr->basic_errno != ERRNO_TLSFAILURE)
2721 write_logs(first_addr, host);
2723 /* If STARTTLS was accepted, but there was a failure in setting up the
2724 TLS session (usually a certificate screwup), and the host is not in
2725 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
2726 TLS forcibly turned off. We have to start from scratch with a new SMTP
2727 connection. That's why the retry is done from here, not from within
2728 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
2729 session, so the in-clear transmission after those errors, if permitted,
2730 happens inside smtp_deliver().] */
2733 if (rc == DEFER && first_addr->basic_errno == ERRNO_TLSFAILURE &&
2734 ob->tls_tempfail_tryclear &&
2735 verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
2736 host->address, NULL) != OK)
2738 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
2739 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
2740 first_addr = prepare_addresses(addrlist, host);
2741 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
2742 expanded_hosts != NULL, &message_defer, TRUE);
2743 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
2744 write_logs(first_addr, host);
2749 /* Delivery attempt finished */
2751 rs = (rc == OK)? US"OK" : (rc == DEFER)? US"DEFER" : (rc == ERROR)?
2754 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
2755 message_id, host->name, host->address, addrlist->address,
2756 (addrlist->next == NULL)? "" : " (& others)", rs);
2758 /* Release serialization if set up */
2760 if (serialized) enq_end(serialize_key);
2762 /* If the result is DEFER, or if a host retry record is known to exist, we
2763 need to add an item to the retry chain for updating the retry database
2764 at the end of delivery. We only need to add the item to the top address,
2765 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
2766 for any other delivery attempts using the same address. (It is copied into
2767 the unusable tree at the outer level, so even if different address blocks
2768 contain the same address, it still won't get tried again.) */
2770 if (rc == DEFER || retry_host_key != NULL)
2772 int delete_flag = (rc != DEFER)? rf_delete : 0;
2773 if (retry_host_key == NULL)
2775 retry_host_key = ob->retry_include_ip_address?
2776 string_sprintf("T:%S:%s%s", host->name, host->address, pistring) :
2777 string_sprintf("T:%S%s", host->name, pistring);
2780 /* If a delivery of another message over an existing SMTP connection
2781 yields DEFER, we do NOT set up retry data for the host. This covers the
2782 case when there are delays in routing the addresses in the second message
2783 that are so long that the server times out. This is alleviated by not
2784 routing addresses that previously had routing defers when handling an
2785 existing connection, but even so, this case may occur (e.g. if a
2786 previously happily routed address starts giving routing defers). If the
2787 host is genuinely down, another non-continued message delivery will
2788 notice it soon enough. */
2790 if (delete_flag != 0 || !continuing)
2791 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
2793 /* We may have tried an expired host, if its retry time has come; ensure
2794 the status reflects the expiry for the benefit of any other addresses. */
2798 host->status = (host_is_expired)?
2799 hstatus_unusable_expired : hstatus_unusable;
2800 host->why = hwhy_deferred;
2804 /* If message_defer is set (host was OK, but every recipient got deferred
2805 because of some message-specific problem), or if that had happened
2806 previously so that a message retry key exists, add an appropriate item
2807 to the retry chain. Note that if there was a message defer but now there is
2808 a host defer, the message defer record gets deleted. That seems perfectly
2809 reasonable. Also, stop the message from being remembered as waiting
2810 for specific hosts. */
2812 if (message_defer || retry_message_key != NULL)
2814 int delete_flag = message_defer? 0 : rf_delete;
2815 if (retry_message_key == NULL)
2817 retry_message_key = ob->retry_include_ip_address?
2818 string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
2820 string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
2822 retry_add_item(addrlist, retry_message_key,
2823 rf_message | rf_host | delete_flag);
2824 update_waiting = FALSE;
2827 /* Any return other than DEFER (that is, OK or ERROR) means that the
2828 addresses have got their final statuses filled in for this host. In the OK
2829 case, see if any of them are deferred. */
2833 for (addr = addrlist; addr != NULL; addr = addr->next)
2835 if (addr->transport_return == DEFER)
2837 some_deferred = TRUE;
2843 /* If no addresses deferred or the result was ERROR, return. We do this for
2844 ERROR because a failing filter set-up or add_headers expansion is likely to
2845 fail for any host we try. */
2847 if (rc == ERROR || (rc == OK && !some_deferred))
2849 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
2850 return TRUE; /* Each address has its status */
2853 /* If the result was DEFER or some individual addresses deferred, let
2854 the loop run to try other hosts with the deferred addresses, except for the
2855 case when we were trying to deliver down an existing channel and failed.
2856 Don't try any other hosts in this case. */
2858 if (continuing) break;
2860 /* If the whole delivery, or some individual addresses, were deferred and
2861 there are more hosts that could be tried, do not count this host towards
2862 the hosts_max_try limit if the age of the message is greater than the
2863 maximum retry time for this host. This means we may try try all hosts,
2864 ignoring the limit, when messages have been around for some time. This is
2865 important because if we don't try all hosts, the address will never time
2866 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
2868 if ((rc == DEFER || some_deferred) && nexthost != NULL)
2871 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
2873 if (retry != NULL && retry->rules != NULL)
2875 retry_rule *last_rule;
2876 for (last_rule = retry->rules;
2877 last_rule->next != NULL;
2878 last_rule = last_rule->next);
2879 timedout = time(NULL) - received_time > last_rule->timeout;
2881 else timedout = TRUE; /* No rule => timed out */
2885 unexpired_hosts_tried--;
2886 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
2887 "hosts_max_try (message older than host's retry time)\n");
2890 } /* End of loop for trying multiple hosts. */
2892 /* This is the end of the loop that repeats iff expired is TRUE and
2893 ob->delay_after_cutoff is FALSE. The second time round we will
2894 try those hosts that haven't been tried since the message arrived. */
2898 debug_printf("all IP addresses skipped or deferred at least one address\n");
2899 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
2900 debug_printf("retrying IP addresses not tried since message arrived\n");
2905 /* Get here if all IP addresses are skipped or defer at least one address. In
2906 MUA wrapper mode, this will happen only for connection or other non-message-
2907 specific failures. Force the delivery status for all addresses to FAIL. */
2911 for (addr = addrlist; addr != NULL; addr = addr->next)
2912 addr->transport_return = FAIL;
2916 /* In the normal, non-wrapper case, add a standard message to each deferred
2917 address if there hasn't been an error, that is, if it hasn't actually been
2918 tried this time. The variable "expired" will be FALSE if any deliveries were
2919 actually tried, or if there was at least one host that was not expired. That
2920 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
2921 a delivery has been tried, an error code will be set, and the failing of the
2922 message is handled by the retry code later.
2924 If queue_smtp is set, or this transport was called to send a subsequent message
2925 down an existing TCP/IP connection, and something caused the host not to be
2926 found, we end up here, but can detect these cases and handle them specially. */
2928 for (addr = addrlist; addr != NULL; addr = addr->next)
2930 /* If host is not NULL, it means that we stopped processing the host list
2931 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
2932 means we need to behave as if some hosts were skipped because their retry
2933 time had not come. Specifically, this prevents the address from timing out.
2934 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
2935 hosts were tried. */
2939 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
2942 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
2943 "hosts were tried\n");
2948 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
2949 setflag(addr, af_retry_skipped);
2953 if (queue_smtp) /* no deliveries attempted */
2955 addr->transport_return = DEFER;
2956 addr->basic_errno = 0;
2957 addr->message = US"SMTP delivery explicitly queued";
2960 else if (addr->transport_return == DEFER &&
2961 (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0) &&
2962 addr->message == NULL)
2964 addr->basic_errno = ERRNO_HRETRY;
2965 if (continue_hostname != NULL)
2967 addr->message = US"no host found for existing SMTP connection";
2971 setflag(addr, af_pass_message); /* This is not a security risk */
2972 addr->message = (ob->delay_after_cutoff)?
2973 US"retry time not reached for any host after a long failure period" :
2974 US"all hosts have been failing for a long time and were last tried "
2975 "after this message arrived";
2977 /* If we are already using fallback hosts, or there are no fallback hosts
2978 defined, convert the result to FAIL to cause a bounce. */
2980 if (addr->host_list == addr->fallback_hosts ||
2981 addr->fallback_hosts == NULL)
2982 addr->transport_return = FAIL;
2986 if (hosts_retry == hosts_total)
2987 addr->message = US"retry time not reached for any host";
2988 else if (hosts_fail == hosts_total)
2989 addr->message = US"all host address lookups failed permanently";
2990 else if (hosts_defer == hosts_total)
2991 addr->message = US"all host address lookups failed temporarily";
2992 else if (hosts_serial == hosts_total)
2993 addr->message = US"connection limit reached for all hosts";
2994 else if (hosts_fail+hosts_defer == hosts_total)
2995 addr->message = US"all host address lookups failed";
2996 else addr->message = US"some host address lookups failed and retry time "
2997 "not reached for other hosts or connection limit reached";
3002 /* Update the database which keeps information about which messages are waiting
3003 for which hosts to become available. For some message-specific errors, the
3004 update_waiting flag is turned off because we don't want follow-on deliveries in
3007 if (update_waiting) transport_update_waiting(hostlist, tblock->name);
3011 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3013 return TRUE; /* Each address has its status */
3016 /* End of transport/smtp.c */