1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2012 */
6 /* See the file NOTICE for conditions of use and distribution. */
12 #define PENDING_DEFER (PENDING + DEFER)
13 #define PENDING_OK (PENDING + OK)
16 /* Options specific to the smtp transport. This transport also supports LMTP
17 over TCP/IP. The options must be in alphabetic order (note that "_" comes
18 before the lower case letters). Some live in the transport_instance block so as
19 to be publicly visible; these are flagged with opt_public. */
21 optionlist smtp_transport_options[] = {
22 { "address_retry_include_sender", opt_bool,
23 (void *)offsetof(smtp_transport_options_block, address_retry_include_sender) },
24 { "allow_localhost", opt_bool,
25 (void *)offsetof(smtp_transport_options_block, allow_localhost) },
26 { "authenticated_sender", opt_stringptr,
27 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
28 { "authenticated_sender_force", opt_bool,
29 (void *)offsetof(smtp_transport_options_block, authenticated_sender_force) },
30 { "command_timeout", opt_time,
31 (void *)offsetof(smtp_transport_options_block, command_timeout) },
32 { "connect_timeout", opt_time,
33 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
34 { "connection_max_messages", opt_int | opt_public,
35 (void *)offsetof(transport_instance, connection_max_messages) },
36 { "data_timeout", opt_time,
37 (void *)offsetof(smtp_transport_options_block, data_timeout) },
38 #ifdef EXPERIMENTAL_DBL
39 { "dbl_host_defer_query", opt_stringptr,
40 (void *)offsetof(smtp_transport_options_block, dbl_host_defer_query) },
42 { "delay_after_cutoff", opt_bool,
43 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
45 { "dkim_canon", opt_stringptr,
46 (void *)offsetof(smtp_transport_options_block, dkim_canon) },
47 { "dkim_domain", opt_stringptr,
48 (void *)offsetof(smtp_transport_options_block, dkim_domain) },
49 { "dkim_private_key", opt_stringptr,
50 (void *)offsetof(smtp_transport_options_block, dkim_private_key) },
51 { "dkim_selector", opt_stringptr,
52 (void *)offsetof(smtp_transport_options_block, dkim_selector) },
53 { "dkim_sign_headers", opt_stringptr,
54 (void *)offsetof(smtp_transport_options_block, dkim_sign_headers) },
55 { "dkim_strict", opt_stringptr,
56 (void *)offsetof(smtp_transport_options_block, dkim_strict) },
58 { "dns_qualify_single", opt_bool,
59 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
60 { "dns_search_parents", opt_bool,
61 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
62 { "dscp", opt_stringptr,
63 (void *)offsetof(smtp_transport_options_block, dscp) },
64 { "fallback_hosts", opt_stringptr,
65 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
66 { "final_timeout", opt_time,
67 (void *)offsetof(smtp_transport_options_block, final_timeout) },
68 { "gethostbyname", opt_bool,
69 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
71 /* These are no longer honoured, as of Exim 4.80; for now, we silently
72 ignore; a later release will warn, and a later-still release will remove
73 these options, so that using them becomes an error. */
74 { "gnutls_require_kx", opt_stringptr,
75 (void *)offsetof(smtp_transport_options_block, gnutls_require_kx) },
76 { "gnutls_require_mac", opt_stringptr,
77 (void *)offsetof(smtp_transport_options_block, gnutls_require_mac) },
78 { "gnutls_require_protocols", opt_stringptr,
79 (void *)offsetof(smtp_transport_options_block, gnutls_require_proto) },
81 { "helo_data", opt_stringptr,
82 (void *)offsetof(smtp_transport_options_block, helo_data) },
83 { "hosts", opt_stringptr,
84 (void *)offsetof(smtp_transport_options_block, hosts) },
85 { "hosts_avoid_esmtp", opt_stringptr,
86 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
87 { "hosts_avoid_pipelining", opt_stringptr,
88 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
90 { "hosts_avoid_tls", opt_stringptr,
91 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
93 { "hosts_max_try", opt_int,
94 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
95 { "hosts_max_try_hardlimit", opt_int,
96 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
98 { "hosts_nopass_tls", opt_stringptr,
99 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
101 { "hosts_override", opt_bool,
102 (void *)offsetof(smtp_transport_options_block, hosts_override) },
103 { "hosts_randomize", opt_bool,
104 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
105 { "hosts_require_auth", opt_stringptr,
106 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
108 # if defined EXPERIMENTAL_OCSP
109 { "hosts_require_ocsp", opt_stringptr,
110 (void *)offsetof(smtp_transport_options_block, hosts_require_ocsp) },
112 { "hosts_require_tls", opt_stringptr,
113 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
115 { "hosts_try_auth", opt_stringptr,
116 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
117 #ifdef EXPERIMENTAL_PRDR
118 { "hosts_try_prdr", opt_stringptr,
119 (void *)offsetof(smtp_transport_options_block, hosts_try_prdr) },
122 { "hosts_verify_avoid_tls", opt_stringptr,
123 (void *)offsetof(smtp_transport_options_block, hosts_verify_avoid_tls) },
125 { "interface", opt_stringptr,
126 (void *)offsetof(smtp_transport_options_block, interface) },
127 { "keepalive", opt_bool,
128 (void *)offsetof(smtp_transport_options_block, keepalive) },
129 { "lmtp_ignore_quota", opt_bool,
130 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
131 { "max_rcpt", opt_int | opt_public,
132 (void *)offsetof(transport_instance, max_addresses) },
133 { "multi_domain", opt_bool | opt_public,
134 (void *)offsetof(transport_instance, multi_domain) },
135 { "port", opt_stringptr,
136 (void *)offsetof(smtp_transport_options_block, port) },
137 { "protocol", opt_stringptr,
138 (void *)offsetof(smtp_transport_options_block, protocol) },
139 { "retry_include_ip_address", opt_bool,
140 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
141 { "serialize_hosts", opt_stringptr,
142 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
143 { "size_addition", opt_int,
144 (void *)offsetof(smtp_transport_options_block, size_addition) }
146 ,{ "tls_certificate", opt_stringptr,
147 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
148 { "tls_crl", opt_stringptr,
149 (void *)offsetof(smtp_transport_options_block, tls_crl) },
150 { "tls_dh_min_bits", opt_int,
151 (void *)offsetof(smtp_transport_options_block, tls_dh_min_bits) },
152 { "tls_privatekey", opt_stringptr,
153 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
154 { "tls_require_ciphers", opt_stringptr,
155 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
156 { "tls_sni", opt_stringptr,
157 (void *)offsetof(smtp_transport_options_block, tls_sni) },
158 { "tls_tempfail_tryclear", opt_bool,
159 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
160 { "tls_verify_certificates", opt_stringptr,
161 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) }
165 /* Size of the options list. An extern variable has to be used so that its
166 address can appear in the tables drtables.c. */
168 int smtp_transport_options_count =
169 sizeof(smtp_transport_options)/sizeof(optionlist);
171 /* Default private options block for the smtp transport. */
173 smtp_transport_options_block smtp_transport_option_defaults = {
175 NULL, /* fallback_hosts */
177 NULL, /* fallback_hostlist */
178 NULL, /* authenticated_sender */
179 US"$primary_hostname", /* helo_data */
180 NULL, /* interface */
182 US"smtp", /* protocol */
184 NULL, /* serialize_hosts */
185 NULL, /* hosts_try_auth */
186 NULL, /* hosts_require_auth */
187 #ifdef EXPERIMENTAL_PRDR
188 NULL, /* hosts_try_prdr */
190 #ifdef EXPERIMENTAL_OCSP
191 NULL, /* hosts_require_ocsp */
193 NULL, /* hosts_require_tls */
194 NULL, /* hosts_avoid_tls */
195 US"*", /* hosts_verify_avoid_tls */
196 NULL, /* hosts_avoid_pipelining */
197 NULL, /* hosts_avoid_esmtp */
198 NULL, /* hosts_nopass_tls */
199 5*60, /* command_timeout */
200 5*60, /* connect_timeout; shorter system default overrides */
201 5*60, /* data timeout */
202 10*60, /* final timeout */
203 1024, /* size_addition */
204 5, /* hosts_max_try */
205 50, /* hosts_max_try_hardlimit */
206 TRUE, /* address_retry_include_sender */
207 FALSE, /* allow_localhost */
208 FALSE, /* authenticated_sender_force */
209 FALSE, /* gethostbyname */
210 TRUE, /* dns_qualify_single */
211 FALSE, /* dns_search_parents */
212 TRUE, /* delay_after_cutoff */
213 FALSE, /* hosts_override */
214 FALSE, /* hosts_randomize */
215 TRUE, /* keepalive */
216 FALSE, /* lmtp_ignore_quota */
217 TRUE /* retry_include_ip_address */
219 ,NULL, /* tls_certificate */
221 NULL, /* tls_privatekey */
222 NULL, /* tls_require_ciphers */
223 NULL, /* gnutls_require_kx */
224 NULL, /* gnutls_require_mac */
225 NULL, /* gnutls_require_proto */
227 NULL, /* tls_verify_certificates */
228 EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
229 /* tls_dh_min_bits */
230 TRUE /* tls_tempfail_tryclear */
233 ,NULL, /* dkim_canon */
234 NULL, /* dkim_domain */
235 NULL, /* dkim_private_key */
236 NULL, /* dkim_selector */
237 NULL, /* dkim_sign_headers */
238 NULL /* dkim_strict */
240 #ifdef EXPERIMENTAL_DBL
241 ,NULL /* dbl_host_defer_query */
248 static uschar *smtp_command; /* Points to last cmd for error messages */
249 static uschar *mail_command; /* Points to MAIL cmd for error messages */
250 static BOOL update_waiting; /* TRUE to update the "wait" database */
253 /*************************************************
254 * Setup entry point *
255 *************************************************/
257 /* This function is called when the transport is about to be used,
258 but before running it in a sub-process. It is used for two things:
260 (1) To set the fallback host list in addresses, when delivering.
261 (2) To pass back the interface, port, protocol, and other options, for use
262 during callout verification.
265 tblock pointer to the transport instance block
266 addrlist list of addresses about to be transported
267 tf if not NULL, pointer to block in which to return options
268 uid the uid that will be set (not used)
269 gid the gid that will be set (not used)
270 errmsg place for error message (not used)
272 Returns: OK always (FAIL, DEFER not used)
276 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
277 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
279 smtp_transport_options_block *ob =
280 (smtp_transport_options_block *)(tblock->options_block);
282 errmsg = errmsg; /* Keep picky compilers happy */
286 /* Pass back options if required. This interface is getting very messy. */
290 tf->interface = ob->interface;
292 tf->protocol = ob->protocol;
293 tf->hosts = ob->hosts;
294 tf->hosts_override = ob->hosts_override;
295 tf->hosts_randomize = ob->hosts_randomize;
296 tf->gethostbyname = ob->gethostbyname;
297 tf->qualify_single = ob->dns_qualify_single;
298 tf->search_parents = ob->dns_search_parents;
299 tf->helo_data = ob->helo_data;
302 /* Set the fallback host list for all the addresses that don't have fallback
303 host lists, provided that the local host wasn't present in the original host
306 if (!testflag(addrlist, af_local_host_removed))
308 for (; addrlist != NULL; addrlist = addrlist->next)
309 if (addrlist->fallback_hosts == NULL)
310 addrlist->fallback_hosts = ob->fallback_hostlist;
318 /*************************************************
319 * Initialization entry point *
320 *************************************************/
322 /* Called for each instance, after its options have been read, to
323 enable consistency checks to be done, or anything else that needs
326 Argument: pointer to the transport instance block
331 smtp_transport_init(transport_instance *tblock)
333 smtp_transport_options_block *ob =
334 (smtp_transport_options_block *)(tblock->options_block);
336 /* Retry_use_local_part defaults FALSE if unset */
338 if (tblock->retry_use_local_part == TRUE_UNSET)
339 tblock->retry_use_local_part = FALSE;
341 /* Set the default port according to the protocol */
343 if (ob->port == NULL)
344 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
345 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
347 /* Set up the setup entry point, to be called before subprocesses for this
350 tblock->setup = smtp_transport_setup;
352 /* Complain if any of the timeouts are zero. */
354 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
355 ob->final_timeout <= 0)
356 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
357 "command, data, or final timeout value is zero for %s transport",
360 /* If hosts_override is set and there are local hosts, set the global
361 flag that stops verify from showing router hosts. */
363 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
365 /* If there are any fallback hosts listed, build a chain of host items
366 for them, but do not do any lookups at this time. */
368 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
375 /*************************************************
376 * Set delivery info into all active addresses *
377 *************************************************/
379 /* Only addresses whose status is >= PENDING are relevant. A lesser
380 status means that an address is not currently being processed.
383 addrlist points to a chain of addresses
384 errno_value to put in each address's errno field
385 msg to put in each address's message field
386 rc to put in each address's transport_return field
387 pass_message if TRUE, set the "pass message" flag in the address
389 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
390 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
391 this particular type of timeout.
397 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
402 if (errno_value == ERRNO_CONNECTTIMEOUT)
404 errno_value = ETIMEDOUT;
405 orvalue = RTEF_CTOUT;
407 for (addr = addrlist; addr != NULL; addr = addr->next)
409 if (addr->transport_return < PENDING) continue;
410 addr->basic_errno = errno_value;
411 addr->more_errno |= orvalue;
415 if (pass_message) setflag(addr, af_pass_message);
417 addr->transport_return = rc;
423 /*************************************************
424 * Check an SMTP response *
425 *************************************************/
427 /* This function is given an errno code and the SMTP response buffer
428 to analyse, together with the host identification for generating messages. It
429 sets an appropriate message and puts the first digit of the response code into
430 the yield variable. If no response was actually read, a suitable digit is
434 host the current host, to get its name for messages
435 errno_value pointer to the errno value
436 more_errno from the top address for use with ERRNO_FILTER_FAIL
437 buffer the SMTP response buffer
438 yield where to put a one-digit SMTP response code
439 message where to put an errror message
440 pass_message set TRUE if message is an SMTP response
442 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
445 static BOOL check_response(host_item *host, int *errno_value, int more_errno,
446 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
450 if (smtp_use_pipelining &&
451 (Ustrcmp(smtp_command, "MAIL") == 0 ||
452 Ustrcmp(smtp_command, "RCPT") == 0 ||
453 Ustrcmp(smtp_command, "DATA") == 0))
456 *yield = '4'; /* Default setting is to give a temporary error */
458 /* Handle response timeout */
460 if (*errno_value == ETIMEDOUT)
462 *message = US string_sprintf("SMTP timeout while connected to %s [%s] "
463 "after %s%s", host->name, host->address, pl, smtp_command);
464 if (transport_count > 0)
465 *message = US string_sprintf("%s (%d bytes written)", *message,
470 /* Handle malformed SMTP response */
472 if (*errno_value == ERRNO_SMTPFORMAT)
474 uschar *malfresp = string_printing(buffer);
475 while (isspace(*malfresp)) malfresp++;
477 *message = string_sprintf("Malformed SMTP reply (an empty line) from "
478 "%s [%s] in response to %s%s", host->name, host->address, pl,
481 *message = string_sprintf("Malformed SMTP reply from %s [%s] in response "
482 "to %s%s: %s", host->name, host->address, pl, smtp_command, malfresp);
486 /* Handle a failed filter process error; can't send QUIT as we mustn't
489 if (*errno_value == ERRNO_FILTER_FAIL)
491 *message = US string_sprintf("transport filter process failed (%d)%s",
493 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
497 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
500 if (*errno_value == ERRNO_CHHEADER_FAIL)
503 US string_sprintf("failed to expand headers_add or headers_remove: %s",
504 expand_string_message);
508 /* Handle failure to write a complete data block */
510 if (*errno_value == ERRNO_WRITEINCOMPLETE)
512 *message = US string_sprintf("failed to write a data block");
516 /* Handle error responses from the remote mailer. */
520 uschar *s = string_printing(buffer);
521 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
522 "host %s [%s]: %s", pl, smtp_command, host->name, host->address, s);
523 *pass_message = TRUE;
528 /* No data was read. If there is no errno, this must be the EOF (i.e.
529 connection closed) case, which causes deferral. An explicit connection reset
530 error has the same effect. Otherwise, put the host's identity in the message,
531 leaving the errno value to be interpreted as well. In all cases, we have to
532 assume the connection is now dead. */
534 if (*errno_value == 0 || *errno_value == ECONNRESET)
536 *errno_value = ERRNO_SMTPCLOSED;
537 *message = US string_sprintf("Remote host %s [%s] closed connection "
538 "in response to %s%s", host->name, host->address, pl, smtp_command);
540 else *message = US string_sprintf("%s [%s]", host->name, host->address);
547 /*************************************************
548 * Write error message to logs *
549 *************************************************/
551 /* This writes to the main log and to the message log.
554 addr the address item containing error information
555 host the current host
561 write_logs(address_item *addr, host_item *host)
563 if (addr->message != NULL)
565 uschar *message = addr->message;
566 if (addr->basic_errno > 0)
567 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
568 log_write(0, LOG_MAIN, "%s", message);
569 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
574 ((log_extra_selector & LX_outgoing_port) != 0)?
575 string_sprintf("%s [%s]:%d", host->name, host->address,
576 (host->port == PORT_NONE)? 25 : host->port)
578 string_sprintf("%s [%s]", host->name, host->address);
579 log_write(0, LOG_MAIN, "%s %s", msg, strerror(addr->basic_errno));
580 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), msg,
581 strerror(addr->basic_errno));
587 #ifdef EXPERIMENTAL_DBL
588 /*************************************************
589 * Write error message to database log *
590 *************************************************/
592 /* This writes to the database log
595 dbl_host_defer_query dbl_host_defer_query from the transport options block
596 addr the address item containing error information
597 host the current host
603 dbl_write_defer_log(uschar *dbl_host_defer_query, address_item *addr, host_item *host)
605 if (dbl_host_defer_query == NULL)
608 dbl_delivery_ip = string_copy(host->address);
609 dbl_delivery_port = (host->port == PORT_NONE)? 25 : host->port;
610 dbl_delivery_fqdn = string_copy(host->name);
611 dbl_delivery_local_part = string_copy(addr->local_part);
612 dbl_delivery_domain = string_copy(addr->domain);
613 dbl_defer_errno = addr->basic_errno;
615 dbl_defer_errstr = NULL;
616 if (addr->message != NULL)
617 if (addr->basic_errno > 0)
618 dbl_defer_errstr = string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno));
620 dbl_defer_errstr = string_copy(addr->message);
621 else if (addr->basic_errno > 0)
622 dbl_defer_errstr = string_copy(strerror(addr->basic_errno));
625 debug_printf(" DBL(host defer): dbl_host_defer_query=|%s| dbl_delivery_IP=%s\n", dbl_host_defer_query, dbl_delivery_ip);
627 expand_string(dbl_host_defer_query);
633 /*************************************************
634 * Synchronize SMTP responses *
635 *************************************************/
637 /* This function is called from smtp_deliver() to receive SMTP responses from
638 the server, and match them up with the commands to which they relate. When
639 PIPELINING is not in use, this function is called after every command, and is
640 therefore somewhat over-engineered, but it is simpler to use a single scheme
641 that works both with and without PIPELINING instead of having two separate sets
644 The set of commands that are buffered up with pipelining may start with MAIL
645 and may end with DATA; in between are RCPT commands that correspond to the
646 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
647 etc.) are never buffered.
649 Errors after MAIL or DATA abort the whole process leaving the response in the
650 buffer. After MAIL, pending responses are flushed, and the original command is
651 re-instated in big_buffer for error messages. For RCPT commands, the remote is
652 permitted to reject some recipient addresses while accepting others. However
653 certain errors clearly abort the whole process. Set the value in
654 transport_return to PENDING_OK if the address is accepted. If there is a
655 subsequent general error, it will get reset accordingly. If not, it will get
656 converted to OK at the end.
659 addrlist the complete address list
660 include_affixes TRUE if affixes include in RCPT
661 sync_addr ptr to the ptr of the one to start scanning at (updated)
662 host the host we are connected to
663 count the number of responses to read
665 include_sender true if 4xx retry is to include the sender it its key
666 pending_MAIL true if the first response is for MAIL
667 pending_DATA 0 if last command sent was not DATA
668 +1 if previously had a good recipient
669 -1 if not previously had a good recipient
670 inblock incoming SMTP block
671 timeout timeout value
672 buffer buffer for reading response
673 buffsize size of buffer
675 Returns: 3 if at least one address had 2xx and one had 5xx
676 2 if at least one address had 5xx but none had 2xx
677 1 if at least one host had a 2xx response, but none had 5xx
678 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
679 -1 timeout while reading RCPT response
680 -2 I/O or other non-response error for RCPT
681 -3 DATA or MAIL failed - errno and buffer set
685 sync_responses(address_item *addrlist, BOOL include_affixes,
686 address_item **sync_addr, host_item *host, int count,
687 BOOL address_retry_include_sender, BOOL pending_MAIL,
688 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
691 address_item *addr = *sync_addr;
694 /* Handle the response for a MAIL command. On error, reinstate the original
695 command in big_buffer for error message use, and flush any further pending
696 responses before returning, except after I/O errors and timeouts. */
701 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
703 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
704 if (errno == 0 && buffer[0] != 0)
706 uschar flushbuffer[4096];
708 if (buffer[0] == '4')
710 save_errno = ERRNO_MAIL4XX;
711 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
715 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
717 && (errno != 0 || flushbuffer[0] == 0))
726 if (pending_DATA) count--; /* Number of RCPT responses to come */
728 /* Read and handle the required number of RCPT responses, matching each one up
729 with an address by scanning for the next address whose status is PENDING_DEFER.
734 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
736 /* The address was accepted */
738 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
741 addr->transport_return = PENDING_OK;
743 /* If af_dr_retry_exists is set, there was a routing delay on this address;
744 ensure that any address-specific retry record is expunged. We do this both
745 for the basic key and for the version that also includes the sender. */
747 if (testflag(addr, af_dr_retry_exists))
749 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
751 retry_add_item(addr, altkey, rf_delete);
752 retry_add_item(addr, addr->address_retry_key, rf_delete);
756 /* Timeout while reading the response */
758 else if (errno == ETIMEDOUT)
760 int save_errno = errno;
761 uschar *message = string_sprintf("SMTP timeout while connected to %s [%s] "
762 "after RCPT TO:<%s>", host->name, host->address,
763 transport_rcpt_address(addr, include_affixes));
764 set_errno(addrlist, save_errno, message, DEFER, FALSE);
765 retry_add_item(addr, addr->address_retry_key, 0);
766 update_waiting = FALSE;
770 /* Handle other errors in obtaining an SMTP response by returning -1. This
771 will cause all the addresses to be deferred. Restore the SMTP command in
772 big_buffer for which we are checking the response, so the error message
775 else if (errno != 0 || buffer[0] == 0)
777 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
778 transport_rcpt_address(addr, include_affixes));
782 /* Handle SMTP permanent and temporary response codes. */
787 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
788 "host %s [%s]: %s", transport_rcpt_address(addr, include_affixes),
789 host->name, host->address, string_printing(buffer));
790 setflag(addr, af_pass_message);
791 deliver_msglog("%s %s\n", tod_stamp(tod_log), addr->message);
793 /* The response was 5xx */
795 if (buffer[0] == '5')
797 addr->transport_return = FAIL;
801 /* The response was 4xx */
805 addr->transport_return = DEFER;
806 addr->basic_errno = ERRNO_RCPT4XX;
807 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
809 /* Log temporary errors if there are more hosts to be tried. */
811 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", addr->message);
813 /* Do not put this message on the list of those waiting for specific
814 hosts, as otherwise it is likely to be tried too often. */
816 update_waiting = FALSE;
818 /* Add a retry item for the address so that it doesn't get tried again
819 too soon. If address_retry_include_sender is true, add the sender address
822 if (address_retry_include_sender)
824 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
826 retry_add_item(addr, altkey, 0);
828 else retry_add_item(addr, addr->address_retry_key, 0);
831 } /* Loop for next RCPT response */
833 /* Update where to start at for the next block of responses, unless we
834 have already handled all the addresses. */
836 if (addr != NULL) *sync_addr = addr->next;
838 /* Handle a response to DATA. If we have not had any good recipients, either
839 previously or in this block, the response is ignored. */
841 if (pending_DATA != 0 &&
842 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
847 if (pending_DATA > 0 || (yield & 1) != 0)
849 if (errno == 0 && buffer[0] == '4')
851 errno = ERRNO_DATA4XX;
852 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
856 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
857 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
858 "is in use and there were no good recipients\n", msg);
861 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
862 present) received 3xx. If any RCPTs were handled and yielded anything other
863 than 4xx, yield will be set non-zero. */
870 /* Do the client side of smtp-level authentication */
873 buffer EHLO response from server (gets overwritten)
874 addrlist chain of potential addresses to deliver
875 host host to deliver to
877 ibp, obp comms channel control blocks
880 OK Success, or failed (but not required): global "smtp_authenticated" set
881 DEFER Failed authentication (and was required)
882 ERROR Internal problem
884 FAIL_SEND Failed communications - transmit
889 smtp_auth(uschar *buffer, unsigned bufsize, address_item *addrlist, host_item *host,
890 smtp_transport_options_block *ob, BOOL is_esmtp,
891 smtp_inblock *ibp, smtp_outblock *obp)
894 uschar *fail_reason = US"server did not advertise AUTH support";
896 smtp_authenticated = FALSE;
897 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
898 require_auth = verify_check_this_host(&(ob->hosts_require_auth), NULL,
899 host->name, host->address, NULL);
901 if (is_esmtp && !regex_AUTH) regex_AUTH =
902 regex_must_compile(US"\\n250[\\s\\-]AUTH\\s+([\\-\\w\\s]+)(?:\\n|$)",
905 if (is_esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
907 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
908 expand_nmax = -1; /* reset */
910 /* Must not do this check until after we have saved the result of the
911 regex match above. */
913 if (require_auth == OK ||
914 verify_check_this_host(&(ob->hosts_try_auth), NULL, host->name,
915 host->address, NULL) == OK)
918 fail_reason = US"no common mechanisms were found";
920 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
922 /* Scan the configured authenticators looking for one which is configured
923 for use as a client, which is not suppressed by client_condition, and
924 whose name matches an authentication mechanism supported by the server.
925 If one is found, attempt to authenticate by calling its client function.
928 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
932 (au->client_condition != NULL &&
933 !expand_check_condition(au->client_condition, au->name,
934 US"client authenticator")))
936 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
938 (au->client)? "client_condition is false" :
939 "not configured as a client");
943 /* Loop to scan supported server mechanisms */
948 int len = Ustrlen(au->public_name);
949 while (isspace(*p)) p++;
951 if (strncmpic(au->public_name, p, len) != 0 ||
952 (p[len] != 0 && !isspace(p[len])))
954 while (*p != 0 && !isspace(*p)) p++;
958 /* Found data for a listed mechanism. Call its client entry. Set
959 a flag in the outblock so that data is overwritten after sending so
960 that reflections don't show it. */
962 fail_reason = US"authentication attempt(s) failed";
963 obp->authenticating = TRUE;
964 rc = (au->info->clientcode)(au, ibp, obp,
965 ob->command_timeout, buffer, bufsize);
966 obp->authenticating = FALSE;
967 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
970 /* A temporary authentication failure must hold up delivery to
971 this host. After a permanent authentication failure, we carry on
972 to try other authentication methods. If all fail hard, try to
973 deliver the message unauthenticated unless require_auth was set. */
978 smtp_authenticated = TRUE; /* stops the outer loop */
979 client_authenticator = au->name;
980 if (au->set_client_id != NULL)
981 client_authenticated_id = expand_string(au->set_client_id);
984 /* Failure after writing a command */
989 /* Failure after reading a response */
992 if (errno != 0 || buffer[0] != '5') return FAIL;
993 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
994 au->name, host->name, host->address, buffer);
997 /* Failure by some other means. In effect, the authenticator
998 decided it wasn't prepared to handle this case. Typically this
999 is the result of "fail" in an expansion string. Do we need to
1000 log anything here? Feb 2006: a message is now put in the buffer
1001 if logging is required. */
1005 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1006 "authentication H=%s [%s] %s", au->name, host->name,
1007 host->address, buffer);
1010 /* Internal problem, message in buffer. */
1013 set_errno(addrlist, 0, string_copy(buffer), DEFER, FALSE);
1017 break; /* If not authenticated, try next authenticator */
1018 } /* Loop for scanning supported server mechanisms */
1019 } /* Loop for further authenticators */
1023 /* If we haven't authenticated, but are required to, give up. */
1025 if (require_auth == OK && !smtp_authenticated)
1027 set_errno(addrlist, ERRNO_AUTHFAIL,
1028 string_sprintf("authentication required but %s", fail_reason), DEFER,
1037 /* Construct AUTH appendix string for MAIL TO */
1040 buffer to build string
1041 addrlist chain of potential addresses to deliver
1042 ob transport options
1044 Globals smtp_authenticated
1045 client_authenticated_sender
1046 Return True on error, otherwise buffer has (possibly empty) terminated string
1050 smtp_mail_auth_str(uschar *buffer, unsigned bufsize, address_item *addrlist,
1051 smtp_transport_options_block *ob)
1053 uschar *local_authenticated_sender = authenticated_sender;
1056 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n", authenticated_sender, ob->authenticated_sender, smtp_authenticated?"Y":"N");
1059 if (ob->authenticated_sender != NULL)
1061 uschar *new = expand_string(ob->authenticated_sender);
1064 if (!expand_string_forcedfail)
1066 uschar *message = string_sprintf("failed to expand "
1067 "authenticated_sender: %s", expand_string_message);
1068 set_errno(addrlist, 0, message, DEFER, FALSE);
1072 else if (new[0] != 0) local_authenticated_sender = new;
1075 /* Add the authenticated sender address if present */
1077 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1078 local_authenticated_sender != NULL)
1080 string_format(buffer, bufsize, " AUTH=%s",
1081 auth_xtextencode(local_authenticated_sender,
1082 Ustrlen(local_authenticated_sender)));
1083 client_authenticated_sender = string_copy(local_authenticated_sender);
1093 /*************************************************
1094 * Deliver address list to given host *
1095 *************************************************/
1097 /* If continue_hostname is not null, we get here only when continuing to
1098 deliver down an existing channel. The channel was passed as the standard
1099 input. TLS is never active on a passed channel; the previous process always
1100 closes it down before passing the connection on.
1102 Otherwise, we have to make a connection to the remote host, and do the
1103 initial protocol exchange.
1105 When running as an MUA wrapper, if the sender or any recipient is rejected,
1106 temporarily or permanently, we force failure for all recipients.
1109 addrlist chain of potential addresses to deliver; only those whose
1110 transport_return field is set to PENDING_DEFER are currently
1111 being processed; others should be skipped - they have either
1112 been delivered to an earlier host or IP address, or been
1113 failed by one of them.
1114 host host to deliver to
1115 host_af AF_INET or AF_INET6
1116 port default TCP/IP port to use, in host byte order
1117 interface interface to bind to, or NULL
1118 tblock transport instance block
1119 copy_host TRUE if host set in addr->host_used must be copied, because
1120 it is specific to this call of the transport
1121 message_defer set TRUE if yield is OK, but all addresses were deferred
1122 because of a non-recipient, non-host failure, that is, a
1123 4xx response to MAIL FROM, DATA, or ".". This is a defer
1124 that is specific to the message.
1125 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1126 a second attempt after TLS initialization fails
1128 Returns: OK - the connection was made and the delivery attempted;
1129 the result for each address is in its data block.
1130 DEFER - the connection could not be made, or something failed
1131 while setting up the SMTP session, or there was a
1132 non-message-specific error, such as a timeout.
1133 ERROR - a filter command is specified for this transport,
1134 and there was a problem setting it up; OR helo_data
1135 or add_headers or authenticated_sender is specified
1136 for this transport, and the string failed to expand
1140 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
1141 uschar *interface, transport_instance *tblock, BOOL copy_host,
1142 BOOL *message_defer, BOOL suppress_tls)
1145 address_item *sync_addr;
1146 address_item *first_addr = addrlist;
1151 time_t start_delivery_time = time(NULL);
1152 smtp_transport_options_block *ob =
1153 (smtp_transport_options_block *)(tblock->options_block);
1154 BOOL lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
1155 BOOL smtps = strcmpic(ob->protocol, US"smtps") == 0;
1157 BOOL send_rset = TRUE;
1158 BOOL send_quit = TRUE;
1159 BOOL setting_up = TRUE;
1160 BOOL completed_address = FALSE;
1163 BOOL pass_message = FALSE;
1164 #ifdef EXPERIMENTAL_PRDR
1165 BOOL prdr_offered = FALSE;
1168 smtp_inblock inblock;
1169 smtp_outblock outblock;
1170 int max_rcpt = tblock->max_addresses;
1171 uschar *igquotstr = US"";
1172 uschar *helo_data = NULL;
1173 uschar *message = NULL;
1174 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
1176 uschar buffer[4096];
1177 uschar inbuffer[4096];
1178 uschar outbuffer[1024];
1180 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
1182 *message_defer = FALSE;
1183 smtp_command = US"initial connection";
1184 if (max_rcpt == 0) max_rcpt = 999999;
1186 /* Set up the buffer for reading SMTP response packets. */
1188 inblock.buffer = inbuffer;
1189 inblock.buffersize = sizeof(inbuffer);
1190 inblock.ptr = inbuffer;
1191 inblock.ptrend = inbuffer;
1193 /* Set up the buffer for holding SMTP commands while pipelining */
1195 outblock.buffer = outbuffer;
1196 outblock.buffersize = sizeof(outbuffer);
1197 outblock.ptr = outbuffer;
1198 outblock.cmd_count = 0;
1199 outblock.authenticating = FALSE;
1201 /* Reset the parameters of a TLS session. */
1204 tls_in.cipher = NULL; /* for back-compatible behaviour */
1205 tls_in.peerdn = NULL;
1206 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1211 tls_out.cipher = NULL; /* the one we may use for this transport */
1212 tls_out.peerdn = NULL;
1213 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1220 set_errno(addrlist, 0, US"TLS support not available", DEFER, FALSE);
1225 /* Make a connection to the host if this isn't a continued delivery, and handle
1226 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
1227 specially so they can be identified for retries. */
1229 if (continue_hostname == NULL)
1231 inblock.sock = outblock.sock =
1232 smtp_connect(host, host_af, port, interface, ob->connect_timeout,
1233 ob->keepalive, ob->dscp); /* This puts port into host->port */
1235 if (inblock.sock < 0)
1237 set_errno(addrlist, (errno == ETIMEDOUT)? ERRNO_CONNECTTIMEOUT : errno,
1238 NULL, DEFER, FALSE);
1242 /* Expand the greeting message while waiting for the initial response. (Makes
1243 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1244 delayed till here so that $sending_interface and $sending_port are set. */
1246 helo_data = expand_string(ob->helo_data);
1248 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1249 is nevertheless a reasonably clean way of programming this kind of logic,
1250 where you want to escape on any error. */
1254 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1255 ob->command_timeout)) goto RESPONSE_FAILED;
1257 /* Now check if the helo_data expansion went well, and sign off cleanly if
1260 if (helo_data == NULL)
1262 uschar *message = string_sprintf("failed to expand helo_data: %s",
1263 expand_string_message);
1264 set_errno(addrlist, 0, message, DEFER, FALSE);
1270 /** Debugging without sending a message
1271 addrlist->transport_return = DEFER;
1275 /* Errors that occur after this point follow an SMTP command, which is
1276 left in big_buffer by smtp_write_command() for use in error messages. */
1278 smtp_command = big_buffer;
1280 /* Tell the remote who we are...
1282 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1283 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1284 greeting is of this form. The assumption was that the far end supports it
1285 properly... but experience shows that there are some that give 5xx responses,
1286 even though the banner includes "ESMTP" (there's a bloody-minded one that
1287 says "ESMTP not spoken here"). Cope with that case.
1289 September 2000: Time has passed, and it seems reasonable now to always send
1290 EHLO at the start. It is also convenient to make the change while installing
1293 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1294 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1295 would be no way to send out the mails, so there is now a host list
1296 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1297 PIPELINING problem as well. Maybe it can also be useful to cure other
1298 problems with broken servers.
1300 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1301 Then somebody tried it with a Microsoft mailer... It seems that all other
1302 mailers use upper case for some reason (the RFC is quite clear about case
1303 independence) so, for peace of mind, I gave in. */
1305 esmtp = verify_check_this_host(&(ob->hosts_avoid_esmtp), NULL,
1306 host->name, host->address, NULL) != OK;
1308 /* Alas; be careful, since this goto is not an error-out, so conceivably
1309 we might set data between here and the target which we assume to exist
1310 and be usable. I can see this coming back to bite us. */
1315 suppress_tls = FALSE;
1316 ob->tls_tempfail_tryclear = FALSE;
1317 smtp_command = US"SSL-on-connect";
1324 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1325 lmtp? "LHLO" : "EHLO", helo_data) < 0)
1327 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1328 ob->command_timeout))
1330 if (errno != 0 || buffer[0] == 0 || lmtp) goto RESPONSE_FAILED;
1337 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1342 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1344 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1345 ob->command_timeout)) goto RESPONSE_FAILED;
1348 /* Set IGNOREQUOTA if the response to LHLO specifies support and the
1349 lmtp_ignore_quota option was set. */
1351 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1352 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1353 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1355 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1358 tls_offered = esmtp &&
1359 pcre_exec(regex_STARTTLS, NULL, CS buffer, Ustrlen(buffer), 0,
1360 PCRE_EOPT, NULL, 0) >= 0;
1363 #ifdef EXPERIMENTAL_PRDR
1364 prdr_offered = esmtp &&
1365 (pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(buffer), 0,
1366 PCRE_EOPT, NULL, 0) >= 0) &&
1367 (verify_check_this_host(&(ob->hosts_try_prdr), NULL, host->name,
1368 host->address, NULL) == OK);
1371 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1375 /* For continuing deliveries down the same channel, the socket is the standard
1376 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1377 below). Set up the pointer to where subsequent commands will be left, for
1378 error messages. Note that smtp_use_size and smtp_use_pipelining will have been
1379 set from the command line if they were set in the process that passed the
1384 inblock.sock = outblock.sock = fileno(stdin);
1385 smtp_command = big_buffer;
1386 host->port = port; /* Record the port that was used */
1389 /* If TLS is available on this connection, whether continued or not, attempt to
1390 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1391 send another EHLO - the server may give a different answer in secure mode. We
1392 use a separate buffer for reading the response to STARTTLS so that if it is
1393 negative, the original EHLO data is available for subsequent analysis, should
1394 the client not be required to use TLS. If the response is bad, copy the buffer
1395 for error analysis. */
1398 if (tls_offered && !suppress_tls &&
1399 verify_check_this_host(&(ob->hosts_avoid_tls), NULL, host->name,
1400 host->address, NULL) != OK)
1402 uschar buffer2[4096];
1403 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1406 /* If there is an I/O error, transmission of this message is deferred. If
1407 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1408 false, we also defer. However, if there is a temporary rejection of STARTTLS
1409 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1410 STARTTLS, we carry on. This means we will try to send the message in clear,
1411 unless the host is in hosts_require_tls (tested below). */
1413 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1414 ob->command_timeout))
1416 if (errno != 0 || buffer2[0] == 0 ||
1417 (buffer2[0] == '4' && !ob->tls_tempfail_tryclear))
1419 Ustrncpy(buffer, buffer2, sizeof(buffer));
1420 goto RESPONSE_FAILED;
1424 /* STARTTLS accepted: try to negotiate a TLS session. */
1429 int rc = tls_client_start(inblock.sock,
1432 ob->tls_certificate,
1435 ob->tls_verify_certificates,
1437 ob->tls_require_ciphers,
1438 #ifdef EXPERIMENTAL_OCSP
1439 ob->hosts_require_ocsp,
1441 ob->tls_dh_min_bits,
1442 ob->command_timeout);
1444 /* TLS negotiation failed; give an error. From outside, this function may
1445 be called again to try in clear on a new connection, if the options permit
1446 it for this host. */
1450 save_errno = ERRNO_TLSFAILURE;
1451 message = US"failure while setting up TLS session";
1456 /* TLS session is set up */
1458 for (addr = addrlist; addr != NULL; addr = addr->next)
1460 if (addr->transport_return == PENDING_DEFER)
1462 addr->cipher = tls_out.cipher;
1463 addr->peerdn = tls_out.peerdn;
1469 /* if smtps, we'll have smtp_command set to something else; always safe to
1471 smtp_command = big_buffer;
1473 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1474 helo_data is null, we are dealing with a connection that was passed from
1475 another process, and so we won't have expanded helo_data above. We have to
1476 expand it here. $sending_ip_address and $sending_port are set up right at the
1477 start of the Exim process (in exim.c). */
1479 if (tls_out.active >= 0)
1482 if (helo_data == NULL)
1484 helo_data = expand_string(ob->helo_data);
1485 if (helo_data == NULL)
1487 uschar *message = string_sprintf("failed to expand helo_data: %s",
1488 expand_string_message);
1489 set_errno(addrlist, 0, message, DEFER, FALSE);
1495 /* For SMTPS we need to wait for the initial OK response. */
1498 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1499 ob->command_timeout)) goto RESPONSE_FAILED;
1503 greeting_cmd = "EHLO";
1506 greeting_cmd = "HELO";
1508 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1511 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1512 lmtp? "LHLO" : greeting_cmd, helo_data) < 0)
1514 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1515 ob->command_timeout))
1516 goto RESPONSE_FAILED;
1519 /* If the host is required to use a secure channel, ensure that we
1522 else if (verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
1523 host->address, NULL) == OK)
1525 save_errno = ERRNO_TLSREQUIRED;
1526 message = string_sprintf("a TLS session is required for %s [%s], but %s",
1527 host->name, host->address,
1528 tls_offered? "an attempt to start TLS failed" :
1529 "the server did not offer TLS support");
1534 /* If TLS is active, we have just started it up and re-done the EHLO command,
1535 so its response needs to be analyzed. If TLS is not active and this is a
1536 continued session down a previously-used socket, we haven't just done EHLO, so
1539 if (continue_hostname == NULL
1541 || tls_out.active >= 0
1545 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
1546 lmtp_ignore_quota option was set. */
1548 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1549 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1550 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1552 /* If the response to EHLO specified support for the SIZE parameter, note
1553 this, provided size_addition is non-negative. */
1555 smtp_use_size = esmtp && ob->size_addition >= 0 &&
1556 pcre_exec(regex_SIZE, NULL, CS buffer, Ustrlen(CS buffer), 0,
1557 PCRE_EOPT, NULL, 0) >= 0;
1559 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
1560 the current host, esmtp will be false, so PIPELINING can never be used. If
1561 the current host matches hosts_avoid_pipelining, don't do it. */
1563 smtp_use_pipelining = esmtp &&
1564 verify_check_this_host(&(ob->hosts_avoid_pipelining), NULL, host->name,
1565 host->address, NULL) != OK &&
1566 pcre_exec(regex_PIPELINING, NULL, CS buffer, Ustrlen(CS buffer), 0,
1567 PCRE_EOPT, NULL, 0) >= 0;
1569 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
1570 smtp_use_pipelining? "" : "not ");
1572 #ifdef EXPERIMENTAL_PRDR
1573 prdr_offered = esmtp &&
1574 pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(CS buffer), 0,
1575 PCRE_EOPT, NULL, 0) >= 0 &&
1576 verify_check_this_host(&(ob->hosts_try_prdr), NULL, host->name,
1577 host->address, NULL) == OK;
1580 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1583 /* Note if the response to EHLO specifies support for the AUTH extension.
1584 If it has, check that this host is one we want to authenticate to, and do
1585 the business. The host name and address must be available when the
1586 authenticator's client driver is running. */
1588 switch (yield = smtp_auth(buffer, sizeof(buffer), addrlist, host,
1589 ob, esmtp, &inblock, &outblock))
1591 default: goto SEND_QUIT;
1593 case FAIL_SEND: goto SEND_FAILED;
1594 case FAIL: goto RESPONSE_FAILED;
1598 /* The setting up of the SMTP call is now complete. Any subsequent errors are
1599 message-specific. */
1603 /* If there is a filter command specified for this transport, we can now
1604 set it up. This cannot be done until the identify of the host is known. */
1606 if (tblock->filter_command != NULL)
1610 sprintf(CS buffer, "%.50s transport", tblock->name);
1611 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
1612 TRUE, DEFER, addrlist, buffer, NULL);
1613 transport_filter_timeout = tblock->filter_timeout;
1615 /* On failure, copy the error to all addresses, abandon the SMTP call, and
1620 set_errno(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
1628 /* For messages that have more than the maximum number of envelope recipients,
1629 we want to send several transactions down the same SMTP connection. (See
1630 comments in deliver.c as to how this reconciles, heuristically, with
1631 remote_max_parallel.) This optimization was added to Exim after the following
1632 code was already working. The simplest way to put it in without disturbing the
1633 code was to use a goto to jump back to this point when there is another
1634 transaction to handle. */
1637 sync_addr = first_addr;
1641 completed_address = FALSE;
1644 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
1645 qualification, send it, adding something to the message size to allow for
1646 imprecision and things that get added en route. Exim keeps the number of lines
1647 in a message, so we can give an accurate value for the original message, but we
1648 need some additional to handle added headers. (Double "." characters don't get
1649 included in the count.) */
1656 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
1660 #ifdef EXPERIMENTAL_PRDR
1661 prdr_active = FALSE;
1664 for (addr = first_addr; addr; addr = addr->next)
1665 if (addr->transport_return == PENDING_DEFER)
1667 for (addr = addr->next; addr; addr = addr->next)
1668 if (addr->transport_return == PENDING_DEFER)
1669 { /* at least two recipients to send */
1671 sprintf(CS p, " PRDR"); p += 5;
1672 goto prdr_is_active;
1680 /* If an authenticated_sender override has been specified for this transport
1681 instance, expand it. If the expansion is forced to fail, and there was already
1682 an authenticated_sender for this message, the original value will be used.
1683 Other expansion failures are serious. An empty result is ignored, but there is
1684 otherwise no check - this feature is expected to be used with LMTP and other
1685 cases where non-standard addresses (e.g. without domains) might be required. */
1687 if (smtp_mail_auth_str(p, sizeof(buffer) - (p-buffer), addrlist, ob))
1690 /* From here until we send the DATA command, we can make use of PIPELINING
1691 if the server host supports it. The code has to be able to check the responses
1692 at any point, for when the buffer fills up, so we write it totally generally.
1693 When PIPELINING is off, each command written reports that it has flushed the
1696 pending_MAIL = TRUE; /* The block starts with MAIL */
1698 rc = smtp_write_command(&outblock, smtp_use_pipelining,
1699 "MAIL FROM:<%s>%s\r\n", return_path, buffer);
1700 mail_command = string_copy(big_buffer); /* Save for later error message */
1704 case -1: /* Transmission error */
1707 case +1: /* Block was sent */
1708 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1709 ob->command_timeout))
1711 if (errno == 0 && buffer[0] == '4')
1713 errno = ERRNO_MAIL4XX;
1714 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1716 goto RESPONSE_FAILED;
1718 pending_MAIL = FALSE;
1722 /* Pass over all the relevant recipient addresses for this host, which are the
1723 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
1724 several before we have to read the responses for those seen so far. This
1725 checking is done by a subroutine because it also needs to be done at the end.
1726 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
1727 the next one if not all are sent.
1729 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
1730 last address because we want to abort if any recipients have any kind of
1731 problem, temporary or permanent. We know that all recipient addresses will have
1732 the PENDING_DEFER status, because only one attempt is ever made, and we know
1733 that max_rcpt will be large, so all addresses will be done at once. */
1735 for (addr = first_addr;
1736 address_count < max_rcpt && addr != NULL;
1742 if (addr->transport_return != PENDING_DEFER) continue;
1745 no_flush = smtp_use_pipelining && (!mua_wrapper || addr->next != NULL);
1747 /* Now send the RCPT command, and process outstanding responses when
1748 necessary. After a timeout on RCPT, we just end the function, leaving the
1749 yield as OK, because this error can often mean that there is a problem with
1750 just one address, so we don't want to delay the host. */
1752 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s\r\n",
1753 transport_rcpt_address(addr, tblock->rcpt_include_affixes), igquotstr);
1754 if (count < 0) goto SEND_FAILED;
1757 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
1758 &sync_addr, host, count, ob->address_retry_include_sender,
1759 pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
1762 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1763 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1766 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1767 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1768 case 0: /* No 2xx or 5xx, but no probs */
1771 case -1: goto END_OFF; /* Timeout on RCPT */
1772 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
1774 pending_MAIL = FALSE; /* Dealt with MAIL */
1776 } /* Loop for next address */
1778 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
1779 permanently or temporarily. We should have flushed and synced after the last
1784 address_item *badaddr;
1785 for (badaddr = first_addr; badaddr != NULL; badaddr = badaddr->next)
1787 if (badaddr->transport_return != PENDING_OK) break;
1789 if (badaddr != NULL)
1791 set_errno(addrlist, 0, badaddr->message, FAIL,
1792 testflag(badaddr, af_pass_message));
1797 /* If ok is TRUE, we know we have got at least one good recipient, and must now
1798 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
1799 have a good recipient buffered up if we are pipelining. We don't want to waste
1800 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
1801 are pipelining. The responses are all handled by sync_responses(). */
1803 if (ok || (smtp_use_pipelining && !mua_wrapper))
1805 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
1806 if (count < 0) goto SEND_FAILED;
1807 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
1808 host, count, ob->address_retry_include_sender, pending_MAIL,
1809 ok? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
1811 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1812 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1815 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
1816 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
1817 case 0: break; /* No 2xx or 5xx, but no probs */
1819 case -1: goto END_OFF; /* Timeout on RCPT */
1820 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
1824 /* Save the first address of the next batch. */
1828 /* If there were no good recipients (but otherwise there have been no
1829 problems), just set ok TRUE, since we have handled address-specific errors
1830 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
1831 for handling the SMTP dot-handling protocol, flagging to apply to headers as
1832 well as body. Set the appropriate timeout value to be used for each chunk.
1833 (Haven't been able to make it work using select() for writing yet.) */
1835 if (!ok) ok = TRUE; else
1837 sigalrm_seen = FALSE;
1838 transport_write_timeout = ob->data_timeout;
1839 smtp_command = US"sending data block"; /* For error messages */
1840 DEBUG(D_transport|D_v)
1841 debug_printf(" SMTP>> writing message and terminating \".\"\n");
1842 transport_count = 0;
1843 #ifndef DISABLE_DKIM
1844 ok = dkim_transport_write_message(addrlist, inblock.sock,
1845 topt_use_crlf | topt_end_dot | topt_escape_headers |
1846 (tblock->body_only? topt_no_headers : 0) |
1847 (tblock->headers_only? topt_no_body : 0) |
1848 (tblock->return_path_add? topt_add_return_path : 0) |
1849 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1850 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1851 0, /* No size limit */
1852 tblock->add_headers, tblock->remove_headers,
1853 US".", US"..", /* Escaping strings */
1854 tblock->rewrite_rules, tblock->rewrite_existflags,
1855 ob->dkim_private_key, ob->dkim_domain, ob->dkim_selector,
1856 ob->dkim_canon, ob->dkim_strict, ob->dkim_sign_headers
1859 ok = transport_write_message(addrlist, inblock.sock,
1860 topt_use_crlf | topt_end_dot | topt_escape_headers |
1861 (tblock->body_only? topt_no_headers : 0) |
1862 (tblock->headers_only? topt_no_body : 0) |
1863 (tblock->return_path_add? topt_add_return_path : 0) |
1864 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
1865 (tblock->envelope_to_add? topt_add_envelope_to : 0),
1866 0, /* No size limit */
1867 tblock->add_headers, tblock->remove_headers,
1868 US".", US"..", /* Escaping strings */
1869 tblock->rewrite_rules, tblock->rewrite_existflags);
1872 /* transport_write_message() uses write() because it is called from other
1873 places to write to non-sockets. This means that under some OS (e.g. Solaris)
1874 it can exit with "Broken pipe" as its error. This really means that the
1875 socket got closed at the far end. */
1877 transport_write_timeout = 0; /* for subsequent transports */
1879 /* Failure can either be some kind of I/O disaster (including timeout),
1880 or the failure of a transport filter or the expansion of added headers. */
1884 buffer[0] = 0; /* There hasn't been a response */
1885 goto RESPONSE_FAILED;
1888 /* We used to send the terminating "." explicitly here, but because of
1889 buffering effects at both ends of TCP/IP connections, you don't gain
1890 anything by keeping it separate, so it might as well go in the final
1891 data buffer for efficiency. This is now done by setting the topt_end_dot
1894 smtp_command = US"end of data";
1896 #ifdef EXPERIMENTAL_PRDR
1897 /* For PRDR we optionally get a partial-responses warning
1898 * followed by the individual responses, before going on with
1899 * the overall response. If we don't get the warning then deal
1900 * with per non-PRDR. */
1903 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '3',
1905 if (!ok && errno == 0)
1908 case '2': prdr_active = FALSE;
1911 case '4': errno = ERRNO_DATA4XX;
1912 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1919 /* For non-PRDR SMTP, we now read a single response that applies to the
1920 whole message. If it is OK, then all the addresses have been delivered. */
1924 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1926 if (!ok && errno == 0 && buffer[0] == '4')
1928 errno = ERRNO_DATA4XX;
1929 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1933 /* For LMTP, we get back a response for every RCPT command that we sent;
1934 some may be accepted and some rejected. For those that get a response, their
1935 status is fixed; any that are accepted have been handed over, even if later
1936 responses crash - at least, that's how I read RFC 2033.
1938 If all went well, mark the recipient addresses as completed, record which
1939 host/IPaddress they were delivered to, and cut out RSET when sending another
1940 message down the same channel. Write the completed addresses to the journal
1941 now so that they are recorded in case there is a crash of hardware or
1942 software before the spool gets updated. Also record the final SMTP
1943 confirmation if needed (for SMTP only). */
1948 int delivery_time = (int)(time(NULL) - start_delivery_time);
1951 uschar *conf = NULL;
1954 /* Make a copy of the host if it is local to this invocation
1955 of the transport. */
1959 thost = store_get(sizeof(host_item));
1961 thost->name = string_copy(host->name);
1962 thost->address = string_copy(host->address);
1966 /* Set up confirmation if needed - applies only to SMTP */
1969 #ifndef EXPERIMENTAL_DBL
1970 (log_extra_selector & LX_smtp_confirmation) != 0 &&
1975 uschar *s = string_printing(buffer);
1976 conf = (s == buffer)? (uschar *)string_copy(s) : s;
1979 /* Process all transported addresses - for LMTP or PRDR, read a status for
1982 for (addr = addrlist; addr != first_addr; addr = addr->next)
1984 if (addr->transport_return != PENDING_OK) continue;
1986 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
1987 remaining addresses. Otherwise, it's a return code for just the one
1988 address. For temporary errors, add a retry item for the address so that
1989 it doesn't get tried again too soon. */
1991 #ifdef EXPERIMENTAL_PRDR
1992 if (lmtp || prdr_active)
1997 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2000 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
2001 addr->message = string_sprintf(
2002 #ifdef EXPERIMENTAL_PRDR
2003 "%s error after %s: %s", prdr_active ? "PRDR":"LMTP",
2005 "LMTP error after %s: %s",
2007 big_buffer, string_printing(buffer));
2008 setflag(addr, af_pass_message); /* Allow message to go to user */
2009 if (buffer[0] == '5')
2010 addr->transport_return = FAIL;
2013 errno = ERRNO_DATA4XX;
2014 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2015 addr->transport_return = DEFER;
2016 #ifdef EXPERIMENTAL_PRDR
2019 retry_add_item(addr, addr->address_retry_key, 0);
2023 completed_address = TRUE; /* NOW we can set this flag */
2024 if ((log_extra_selector & LX_smtp_confirmation) != 0)
2026 uschar *s = string_printing(buffer);
2027 conf = (s == buffer)? (uschar *)string_copy(s) : s;
2031 /* SMTP, or success return from LMTP for this address. Pass back the
2032 actual host that was used. */
2034 addr->transport_return = OK;
2035 addr->more_errno = delivery_time;
2036 addr->host_used = thost;
2037 addr->special_action = flag;
2038 addr->message = conf;
2039 #ifdef EXPERIMENTAL_PRDR
2040 if (prdr_active) addr->flags |= af_prdr_used;
2044 #ifdef EXPERIMENTAL_PRDR
2048 /* Update the journal. For homonymic addresses, use the base address plus
2049 the transport name. See lots of comments in deliver.c about the reasons
2050 for the complications when homonyms are involved. Just carry on after
2051 write error, as it may prove possible to update the spool file later. */
2053 if (testflag(addr, af_homonym))
2054 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2056 sprintf(CS buffer, "%.500s\n", addr->unique);
2058 DEBUG(D_deliver) debug_printf("journalling %s", buffer);
2059 len = Ustrlen(CS buffer);
2060 if (write(journal_fd, buffer, len) != len)
2061 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2062 "%s: %s", buffer, strerror(errno));
2066 #ifdef EXPERIMENTAL_PRDR
2069 /* PRDR - get the final, overall response. For any non-success
2070 upgrade all the address statuses. */
2071 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2075 if(errno == 0 && buffer[0] == '4')
2077 errno = ERRNO_DATA4XX;
2078 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2080 for (addr = addrlist; addr != first_addr; addr = addr->next)
2081 if (buffer[0] == '5' || addr->transport_return == OK)
2082 addr->transport_return = PENDING_OK; /* allow set_errno action */
2083 goto RESPONSE_FAILED;
2086 /* Update the journal, or setup retry. */
2087 for (addr = addrlist; addr != first_addr; addr = addr->next)
2088 if (addr->transport_return == OK)
2090 if (testflag(addr, af_homonym))
2091 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2093 sprintf(CS buffer, "%.500s\n", addr->unique);
2095 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s", buffer);
2096 len = Ustrlen(CS buffer);
2097 if (write(journal_fd, buffer, len) != len)
2098 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2099 "%s: %s", buffer, strerror(errno));
2101 else if (addr->transport_return == DEFER)
2102 retry_add_item(addr, addr->address_retry_key, -2);
2106 /* Ensure the journal file is pushed out to disk. */
2108 if (EXIMfsync(journal_fd) < 0)
2109 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
2115 /* Handle general (not specific to one address) failures here. The value of ok
2116 is used to skip over this code on the falling through case. A timeout causes a
2117 deferral. Other errors may defer or fail according to the response code, and
2118 may set up a special errno value, e.g. after connection chopped, which is
2119 assumed if errno == 0 and there is no text in the buffer. If control reaches
2120 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
2121 the problem is not related to this specific message. */
2130 send_quit = check_response(host, &save_errno, addrlist->more_errno,
2131 buffer, &code, &message, &pass_message);
2137 message = US string_sprintf("send() to %s [%s] failed: %s",
2138 host->name, host->address, strerror(save_errno));
2142 /* This label is jumped to directly when a TLS negotiation has failed,
2143 or was not done for a host for which it is required. Values will be set
2144 in message and save_errno, and setting_up will always be true. Treat as
2145 a temporary error. */
2152 /* If the failure happened while setting up the call, see if the failure was
2153 a 5xx response (this will either be on connection, or following HELO - a 5xx
2154 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
2155 never going to accept them. For other errors during setting up (timeouts or
2156 whatever), defer all addresses, and yield DEFER, so that the host is not
2157 tried again for a while. */
2160 ok = FALSE; /* For when reached by GOTO */
2166 set_errno(addrlist, save_errno, message, FAIL, pass_message);
2170 set_errno(addrlist, save_errno, message, DEFER, pass_message);
2175 /* We want to handle timeouts after MAIL or "." and loss of connection after
2176 "." specially. They can indicate a problem with the sender address or with
2177 the contents of the message rather than a real error on the connection. These
2178 cases are treated in the same way as a 4xx response. This next bit of code
2179 does the classification. */
2190 message_error = TRUE;
2194 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
2195 Ustrncmp(smtp_command,"end ",4) == 0;
2198 case ERRNO_SMTPCLOSED:
2199 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
2203 message_error = FALSE;
2207 /* Handle the cases that are treated as message errors. These are:
2209 (a) negative response or timeout after MAIL
2210 (b) negative response after DATA
2211 (c) negative response or timeout or dropped connection after "."
2213 It won't be a negative response or timeout after RCPT, as that is dealt
2214 with separately above. The action in all cases is to set an appropriate
2215 error code for all the addresses, but to leave yield set to OK because the
2216 host itself has not failed. Of course, it might in practice have failed
2217 when we've had a timeout, but if so, we'll discover that at the next
2218 delivery attempt. For a temporary error, set the message_defer flag, and
2219 write to the logs for information if this is not the last host. The error
2220 for the last host will be logged as part of the address's log line. */
2224 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
2225 set_errno(addrlist, save_errno, message, (code == '5')? FAIL : DEFER,
2228 /* If there's an errno, the message contains just the identity of
2231 if (code != '5') /* Anything other than 5 is treated as temporary */
2234 message = US string_sprintf("%s: %s", message, strerror(save_errno));
2235 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
2236 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
2237 *message_defer = TRUE;
2241 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
2242 ".", or some other transportation error. We defer all addresses and yield
2243 DEFER, except for the case of failed add_headers expansion, or a transport
2244 filter failure, when the yield should be ERROR, to stop it trying other
2249 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
2250 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
2251 set_errno(addrlist, save_errno, message, DEFER, pass_message);
2257 /* If all has gone well, send_quit will be set TRUE, implying we can end the
2258 SMTP session tidily. However, if there were too many addresses to send in one
2259 message (indicated by first_addr being non-NULL) we want to carry on with the
2260 rest of them. Also, it is desirable to send more than one message down the SMTP
2261 connection if there are several waiting, provided we haven't already sent so
2262 many as to hit the configured limit. The function transport_check_waiting looks
2263 for a waiting message and returns its id. Then transport_pass_socket tries to
2264 set up a continued delivery by passing the socket on to another process. The
2265 variable send_rset is FALSE if a message has just been successfully transfered.
2267 If we are already sending down a continued channel, there may be further
2268 addresses not yet delivered that are aimed at the same host, but which have not
2269 been passed in this run of the transport. In this case, continue_more will be
2270 true, and all we should do is send RSET if necessary, and return, leaving the
2273 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
2274 do not want to continue with other messages down the same channel, because that
2275 can lead to looping between two or more messages, all with the same,
2276 temporarily failing address(es). [The retry information isn't updated yet, so
2277 new processes keep on trying.] We probably also don't want to try more of this
2278 message's addresses either.
2280 If we have started a TLS session, we have to end it before passing the
2281 connection to a new process. However, not all servers can handle this (Exim
2282 can), so we do not pass such a connection on if the host matches
2283 hosts_nopass_tls. */
2286 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
2287 "yield=%d first_address is %sNULL\n", ok, send_quit, send_rset,
2288 continue_more, yield, (first_addr == NULL)? "":"not ");
2290 if (completed_address && ok && send_quit)
2293 if (first_addr != NULL || continue_more ||
2295 (tls_out.active < 0 ||
2296 verify_check_this_host(&(ob->hosts_nopass_tls), NULL, host->name,
2297 host->address, NULL) != OK)
2299 transport_check_waiting(tblock->name, host->name,
2300 tblock->connection_max_messages, new_message_id, &more)
2308 if (! (ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
2310 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
2311 host->address, strerror(save_errno));
2314 else if (! (ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2315 ob->command_timeout)))
2318 send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
2322 DEBUG(D_transport) debug_printf("%s\n", msg);
2327 /* Either RSET was not needed, or it succeeded */
2331 if (first_addr != NULL) /* More addresses still to be sent */
2332 { /* in this run of the transport */
2333 continue_sequence++; /* Causes * in logging */
2336 if (continue_more) return yield; /* More addresses for another run */
2338 /* Pass the socket to a new Exim process. Before doing so, we must shut
2339 down TLS. Not all MTAs allow for the continuation of the SMTP session
2340 when TLS is shut down. We test for this by sending a new EHLO. If we
2341 don't get a good response, we don't attempt to pass the socket on. */
2344 if (tls_out.active >= 0)
2346 tls_close(FALSE, TRUE);
2350 ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
2351 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2352 ob->command_timeout);
2356 /* If the socket is successfully passed, we musn't send QUIT (or
2357 indeed anything!) from here. */
2359 if (ok && transport_pass_socket(tblock->name, host->name, host->address,
2360 new_message_id, inblock.sock))
2366 /* If RSET failed and there are addresses left, they get deferred. */
2368 else set_errno(first_addr, errno, msg, DEFER, FALSE);
2372 /* End off tidily with QUIT unless the connection has died or the socket has
2373 been passed to another process. There has been discussion on the net about what
2374 to do after sending QUIT. The wording of the RFC suggests that it is necessary
2375 to wait for a response, but on the other hand, there isn't anything one can do
2376 with an error response, other than log it. Exim used to do that. However,
2377 further discussion suggested that it is positively advantageous not to wait for
2378 the response, but to close the session immediately. This is supposed to move
2379 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
2380 load from the server. (Hosts that are both servers and clients may not see much
2381 difference, of course.) Further discussion indicated that this was safe to do
2382 on Unix systems which have decent implementations of TCP/IP that leave the
2383 connection around for a while (TIME_WAIT) after the application has gone away.
2384 This enables the response sent by the server to be properly ACKed rather than
2385 timed out, as can happen on broken TCP/IP implementations on other OS.
2387 This change is being made on 31-Jul-98. After over a year of trouble-free
2388 operation, the old commented-out code was removed on 17-Sep-99. */
2391 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2396 tls_close(FALSE, TRUE);
2399 /* Close the socket, and return the appropriate value, first setting
2400 continue_transport and continue_hostname NULL to prevent any other addresses
2401 that may include the host from trying to re-use a continuation socket. This
2402 works because the NULL setting is passed back to the calling process, and
2403 remote_max_parallel is forced to 1 when delivering over an existing connection,
2405 If all went well and continue_more is set, we shouldn't actually get here if
2406 there are further addresses, as the return above will be taken. However,
2407 writing RSET might have failed, or there may be other addresses whose hosts are
2408 specified in the transports, and therefore not visible at top level, in which
2409 case continue_more won't get set. */
2411 (void)close(inblock.sock);
2412 continue_transport = NULL;
2413 continue_hostname = NULL;
2420 /*************************************************
2421 * Closedown entry point *
2422 *************************************************/
2424 /* This function is called when exim is passed an open smtp channel
2425 from another incarnation, but the message which it has been asked
2426 to deliver no longer exists. The channel is on stdin.
2428 We might do fancy things like looking for another message to send down
2429 the channel, but if the one we sought has gone, it has probably been
2430 delivered by some other process that itself will seek further messages,
2431 so just close down our connection.
2433 Argument: pointer to the transport instance block
2438 smtp_transport_closedown(transport_instance *tblock)
2440 smtp_transport_options_block *ob =
2441 (smtp_transport_options_block *)(tblock->options_block);
2442 smtp_inblock inblock;
2443 smtp_outblock outblock;
2445 uschar inbuffer[4096];
2446 uschar outbuffer[16];
2448 inblock.sock = fileno(stdin);
2449 inblock.buffer = inbuffer;
2450 inblock.buffersize = sizeof(inbuffer);
2451 inblock.ptr = inbuffer;
2452 inblock.ptrend = inbuffer;
2454 outblock.sock = inblock.sock;
2455 outblock.buffersize = sizeof(outbuffer);
2456 outblock.buffer = outbuffer;
2457 outblock.ptr = outbuffer;
2458 outblock.cmd_count = 0;
2459 outblock.authenticating = FALSE;
2461 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2462 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2463 ob->command_timeout);
2464 (void)close(inblock.sock);
2469 /*************************************************
2470 * Prepare addresses for delivery *
2471 *************************************************/
2473 /* This function is called to flush out error settings from previous delivery
2474 attempts to other hosts. It also records whether we got here via an MX record
2475 or not in the more_errno field of the address. We are interested only in
2476 addresses that are still marked DEFER - others may have got delivered to a
2477 previously considered IP address. Set their status to PENDING_DEFER to indicate
2478 which ones are relevant this time.
2481 addrlist the list of addresses
2482 host the host we are delivering to
2484 Returns: the first address for this delivery
2487 static address_item *
2488 prepare_addresses(address_item *addrlist, host_item *host)
2490 address_item *first_addr = NULL;
2492 for (addr = addrlist; addr != NULL; addr = addr->next)
2494 if (addr->transport_return != DEFER) continue;
2495 if (first_addr == NULL) first_addr = addr;
2496 addr->transport_return = PENDING_DEFER;
2497 addr->basic_errno = 0;
2498 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
2499 addr->message = NULL;
2501 addr->cipher = NULL;
2502 addr->peerdn = NULL;
2510 /*************************************************
2511 * Main entry point *
2512 *************************************************/
2514 /* See local README for interface details. As this is a remote transport, it is
2515 given a chain of addresses to be delivered in one connection, if possible. It
2516 always returns TRUE, indicating that each address has its own independent
2517 status set, except if there is a setting up problem, in which case it returns
2521 smtp_transport_entry(
2522 transport_instance *tblock, /* data for this instantiation */
2523 address_item *addrlist) /* addresses we are working on */
2527 int hosts_defer = 0;
2529 int hosts_looked_up = 0;
2530 int hosts_retry = 0;
2531 int hosts_serial = 0;
2532 int hosts_total = 0;
2533 int total_hosts_tried = 0;
2535 BOOL expired = TRUE;
2536 BOOL continuing = continue_hostname != NULL;
2537 uschar *expanded_hosts = NULL;
2539 uschar *tid = string_sprintf("%s transport", tblock->name);
2540 smtp_transport_options_block *ob =
2541 (smtp_transport_options_block *)(tblock->options_block);
2542 host_item *hostlist = addrlist->host_list;
2543 host_item *host = NULL;
2547 debug_printf("%s transport entered\n", tblock->name);
2548 for (addr = addrlist; addr != NULL; addr = addr->next)
2549 debug_printf(" %s\n", addr->address);
2550 if (continuing) debug_printf("already connected to %s [%s]\n",
2551 continue_hostname, continue_host_address);
2554 /* Set the flag requesting that these hosts be added to the waiting
2555 database if the delivery fails temporarily or if we are running with
2556 queue_smtp or a 2-stage queue run. This gets unset for certain
2557 kinds of error, typically those that are specific to the message. */
2559 update_waiting = TRUE;
2561 /* If a host list is not defined for the addresses - they must all have the
2562 same one in order to be passed to a single transport - or if the transport has
2563 a host list with hosts_override set, use the host list supplied with the
2564 transport. It is an error for this not to exist. */
2566 if (hostlist == NULL || (ob->hosts_override && ob->hosts != NULL))
2568 if (ob->hosts == NULL)
2570 addrlist->message = string_sprintf("%s transport called with no hosts set",
2572 addrlist->transport_return = PANIC;
2573 return FALSE; /* Only top address has status */
2576 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
2579 /* If the transport's host list contains no '$' characters, and we are not
2580 randomizing, it is fixed and therefore a chain of hosts can be built once
2581 and for all, and remembered for subsequent use by other calls to this
2582 transport. If, on the other hand, the host list does contain '$', or we are
2583 randomizing its order, we have to rebuild it each time. In the fixed case,
2584 as the hosts string will never be used again, it doesn't matter that we
2585 replace all the : characters with zeros. */
2587 if (ob->hostlist == NULL)
2589 uschar *s = ob->hosts;
2591 if (Ustrchr(s, '$') != NULL)
2593 expanded_hosts = expand_string(s);
2594 if (expanded_hosts == NULL)
2596 addrlist->message = string_sprintf("failed to expand list of hosts "
2597 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
2598 addrlist->transport_return = search_find_defer? DEFER : PANIC;
2599 return FALSE; /* Only top address has status */
2601 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
2602 "\"%s\"\n", s, expanded_hosts);
2606 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
2608 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
2610 /* Check that the expansion yielded something useful. */
2611 if (hostlist == NULL)
2614 string_sprintf("%s transport has empty hosts setting", tblock->name);
2615 addrlist->transport_return = PANIC;
2616 return FALSE; /* Only top address has status */
2619 /* If there was no expansion of hosts, save the host list for
2622 if (expanded_hosts == NULL) ob->hostlist = hostlist;
2625 /* This is not the first time this transport has been run in this delivery;
2626 the host list was built previously. */
2628 else hostlist = ob->hostlist;
2631 /* The host list was supplied with the address. If hosts_randomize is set, we
2632 must sort it into a random order if it did not come from MX records and has not
2633 already been randomized (but don't bother if continuing down an existing
2636 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continuing)
2638 host_item *newlist = NULL;
2639 while (hostlist != NULL)
2641 host_item *h = hostlist;
2642 hostlist = hostlist->next;
2644 h->sort_key = random_number(100);
2646 if (newlist == NULL)
2651 else if (h->sort_key < newlist->sort_key)
2658 host_item *hh = newlist;
2659 while (hh->next != NULL)
2661 if (h->sort_key < hh->next->sort_key) break;
2669 hostlist = addrlist->host_list = newlist;
2673 /* Sort out the default port. */
2675 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
2678 /* For each host-plus-IP-address on the list:
2680 . If this is a continued delivery and the host isn't the one with the
2681 current connection, skip.
2683 . If the status is unusable (i.e. previously failed or retry checked), skip.
2685 . If no IP address set, get the address, either by turning the name into
2686 an address, calling gethostbyname if gethostbyname is on, or by calling
2687 the DNS. The DNS may yield multiple addresses, in which case insert the
2688 extra ones into the list.
2690 . Get the retry data if not previously obtained for this address and set the
2691 field which remembers the state of this address. Skip if the retry time is
2692 not reached. If not, remember whether retry data was found. The retry string
2693 contains both the name and the IP address.
2695 . Scan the list of addresses and mark those whose status is DEFER as
2696 PENDING_DEFER. These are the only ones that will be processed in this cycle
2699 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
2700 Some addresses may be successfully delivered, others may fail, and yet
2701 others may get temporary errors and so get marked DEFER.
2703 . The return from the delivery attempt is OK if a connection was made and a
2704 valid SMTP dialogue was completed. Otherwise it is DEFER.
2706 . If OK, add a "remove" retry item for this host/IPaddress, if any.
2708 . If fail to connect, or other defer state, add a retry item.
2710 . If there are any addresses whose status is still DEFER, carry on to the
2711 next host/IPaddress, unless we have tried the number of hosts given
2712 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
2713 there is some fancy logic for hosts_max_try that means its limit can be
2714 overstepped in some circumstances.
2716 If we get to the end of the list, all hosts have deferred at least one address,
2717 or not reached their retry times. If delay_after_cutoff is unset, it requests a
2718 delivery attempt to those hosts whose last try was before the arrival time of
2719 the current message. To cope with this, we have to go round the loop a second
2720 time. After that, set the status and error data for any addresses that haven't
2721 had it set already. */
2723 for (cutoff_retry = 0; expired &&
2724 cutoff_retry < ((ob->delay_after_cutoff)? 1 : 2);
2727 host_item *nexthost = NULL;
2728 int unexpired_hosts_tried = 0;
2730 for (host = hostlist;
2732 unexpired_hosts_tried < ob->hosts_max_try &&
2733 total_hosts_tried < ob->hosts_max_try_hardlimit;
2739 BOOL serialized = FALSE;
2740 BOOL host_is_expired = FALSE;
2741 BOOL message_defer = FALSE;
2742 BOOL ifchanges = FALSE;
2743 BOOL some_deferred = FALSE;
2744 address_item *first_addr = NULL;
2745 uschar *interface = NULL;
2746 uschar *retry_host_key = NULL;
2747 uschar *retry_message_key = NULL;
2748 uschar *serialize_key = NULL;
2750 /* Default next host is next host. :-) But this can vary if the
2751 hosts_max_try limit is hit (see below). It may also be reset if a host
2752 address is looked up here (in case the host was multihomed). */
2754 nexthost = host->next;
2756 /* If the address hasn't yet been obtained from the host name, look it up
2757 now, unless the host is already marked as unusable. If it is marked as
2758 unusable, it means that the router was unable to find its IP address (in
2759 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
2760 the lookup failed last time. We don't get this far if *all* MX records
2761 point to non-existent hosts; that is treated as a hard error.
2763 We can just skip this host entirely. When the hosts came from the router,
2764 the address will timeout based on the other host(s); when the address is
2765 looked up below, there is an explicit retry record added.
2767 Note that we mustn't skip unusable hosts if the address is not unset; they
2768 may be needed as expired hosts on the 2nd time round the cutoff loop. */
2770 if (host->address == NULL)
2772 int new_port, flags;
2774 uschar *canonical_name;
2776 if (host->status >= hstatus_unusable)
2778 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
2783 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
2785 /* The host name is permitted to have an attached port. Find it, and
2786 strip it from the name. Just remember it for now. */
2788 new_port = host_item_get_port(host);
2790 /* Count hosts looked up */
2794 /* Find by name if so configured, or if it's an IP address. We don't
2795 just copy the IP address, because we need the test-for-local to happen. */
2797 flags = HOST_FIND_BY_A;
2798 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
2799 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
2801 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
2802 rc = host_find_byname(host, NULL, flags, &canonical_name, TRUE);
2804 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
2805 &canonical_name, NULL);
2807 /* Update the host (and any additional blocks, resulting from
2808 multihoming) with a host-specific port, if any. */
2810 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
2812 /* Failure to find the host at this time (usually DNS temporary failure)
2813 is really a kind of routing failure rather than a transport failure.
2814 Therefore we add a retry item of the routing kind, not to stop us trying
2815 to look this name up here again, but to ensure the address gets timed
2816 out if the failures go on long enough. A complete failure at this point
2817 commonly points to a configuration error, but the best action is still
2818 to carry on for the next host. */
2820 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
2822 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
2824 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
2825 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
2826 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
2827 host->status = hstatus_unusable;
2829 for (addr = addrlist; addr != NULL; addr = addr->next)
2831 if (addr->transport_return != DEFER) continue;
2832 addr->basic_errno = ERRNO_UNKNOWNHOST;
2834 string_sprintf("failed to lookup IP address for %s", host->name);
2839 /* If the host is actually the local host, we may have a problem, or
2840 there may be some cunning configuration going on. In the problem case,
2841 log things and give up. The default transport status is already DEFER. */
2843 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
2845 for (addr = addrlist; addr != NULL; addr = addr->next)
2847 addr->basic_errno = 0;
2848 addr->message = string_sprintf("%s transport found host %s to be "
2849 "local", tblock->name, host->name);
2853 } /* End of block for IP address lookup */
2855 /* If this is a continued delivery, we are interested only in the host
2856 which matches the name of the existing open channel. The check is put
2857 here after the local host lookup, in case the name gets expanded as a
2858 result of the lookup. Set expired FALSE, to save the outer loop executing
2861 if (continuing && (Ustrcmp(continue_hostname, host->name) != 0 ||
2862 Ustrcmp(continue_host_address, host->address) != 0))
2865 continue; /* With next host */
2868 /* Reset the default next host in case a multihomed host whose addresses
2869 are not looked up till just above added to the host list. */
2871 nexthost = host->next;
2873 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
2874 domain is in queue_smtp_domains, we don't actually want to attempt any
2875 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
2876 there is a lookup defer in queue_smtp_domains, proceed as if the domain
2877 were not in it. We don't want to hold up all SMTP deliveries! Except when
2878 doing a two-stage queue run, don't do this if forcing. */
2880 if ((!deliver_force || queue_2stage) && (queue_smtp ||
2881 match_isinlist(addrlist->domain, &queue_smtp_domains, 0,
2882 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
2885 for (addr = addrlist; addr != NULL; addr = addr->next)
2887 if (addr->transport_return != DEFER) continue;
2888 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
2890 continue; /* With next host */
2893 /* Count hosts being considered - purely for an intelligent comment
2894 if none are usable. */
2898 /* Set $host and $host address now in case they are needed for the
2899 interface expansion or the serialize_hosts check; they remain set if an
2900 actual delivery happens. */
2902 deliver_host = host->name;
2903 deliver_host_address = host->address;
2905 /* Set up a string for adding to the retry key if the port number is not
2906 the standard SMTP port. A host may have its own port setting that overrides
2909 pistring = string_sprintf(":%d", (host->port == PORT_NONE)?
2911 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
2913 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
2914 string changes upon expansion, we must add it to the key that is used for
2915 retries, because connections to the same host from a different interface
2916 should be treated separately. */
2918 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET : AF_INET6;
2919 if (!smtp_get_interface(ob->interface, host_af, addrlist, &ifchanges,
2922 if (ifchanges) pistring = string_sprintf("%s/%s", pistring, interface);
2924 /* The first time round the outer loop, check the status of the host by
2925 inspecting the retry data. The second time round, we are interested only
2926 in expired hosts that haven't been tried since this message arrived. */
2928 if (cutoff_retry == 0)
2930 /* Ensure the status of the address is set by checking retry data if
2931 necessary. There maybe host-specific retry data (applicable to all
2932 messages) and also data for retries of a specific message at this host.
2933 If either of these retry records are actually read, the keys used are
2934 returned to save recomputing them later. */
2936 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
2937 ob->retry_include_ip_address, &retry_host_key, &retry_message_key);
2939 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
2940 (host->address == NULL)? US"" : host->address, pistring,
2941 (host->status == hstatus_usable)? "usable" :
2942 (host->status == hstatus_unusable)? "unusable" :
2943 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
2945 /* Skip this address if not usable at this time, noting if it wasn't
2946 actually expired, both locally and in the address. */
2948 switch (host->status)
2950 case hstatus_unusable:
2952 setflag(addrlist, af_retry_skipped);
2955 case hstatus_unusable_expired:
2958 case hwhy_retry: hosts_retry++; break;
2959 case hwhy_failed: hosts_fail++; break;
2960 case hwhy_deferred: hosts_defer++; break;
2963 /* If there was a retry message key, implying that previously there
2964 was a message-specific defer, we don't want to update the list of
2965 messages waiting for these hosts. */
2967 if (retry_message_key != NULL) update_waiting = FALSE;
2968 continue; /* With the next host or IP address */
2972 /* Second time round the loop: if the address is set but expired, and
2973 the message is newer than the last try, let it through. */
2977 if (host->address == NULL ||
2978 host->status != hstatus_unusable_expired ||
2979 host->last_try > received_time)
2982 debug_printf("trying expired host %s [%s]%s\n",
2983 host->name, host->address, pistring);
2984 host_is_expired = TRUE;
2987 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
2988 it remains TRUE only if all hosts are expired and none are actually tried.
2993 /* If this host is listed as one to which access must be serialized,
2994 see if another Exim process has a connection to it, and if so, skip
2995 this host. If not, update the database to record our connection to it
2996 and remember this for later deletion. Do not do any of this if we are
2997 sending the message down a pre-existing connection. */
3000 verify_check_this_host(&(ob->serialize_hosts), NULL, host->name,
3001 host->address, NULL) == OK)
3003 serialize_key = string_sprintf("host-serialize-%s", host->name);
3004 if (!enq_start(serialize_key))
3007 debug_printf("skipping host %s because another Exim process "
3008 "is connected to it\n", host->name);
3015 /* OK, we have an IP address that is not waiting for its retry time to
3016 arrive (it might be expired) OR (second time round the loop) we have an
3017 expired host that hasn't been tried since the message arrived. Have a go
3018 at delivering the message to it. First prepare the addresses by flushing
3019 out the result of previous attempts, and finding the first address that
3020 is still to be delivered. */
3022 first_addr = prepare_addresses(addrlist, host);
3024 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
3025 message_id, host->name, host->address, addrlist->address,
3026 (addrlist->next == NULL)? "" : ", ...");
3028 set_process_info("delivering %s to %s [%s] (%s%s)",
3029 message_id, host->name, host->address, addrlist->address,
3030 (addrlist->next == NULL)? "" : ", ...");
3032 /* This is not for real; don't do the delivery. If there are
3033 any remaining hosts, list them. */
3038 set_errno(addrlist, 0, NULL, OK, FALSE);
3039 for (addr = addrlist; addr != NULL; addr = addr->next)
3041 addr->host_used = host;
3042 addr->special_action = '*';
3043 addr->message = US"delivery bypassed by -N option";
3047 debug_printf("*** delivery by %s transport bypassed by -N option\n"
3048 "*** host and remaining hosts:\n", tblock->name);
3049 for (host2 = host; host2 != NULL; host2 = host2->next)
3050 debug_printf(" %s [%s]\n", host2->name,
3051 (host2->address == NULL)? US"unset" : host2->address);
3056 /* This is for real. If the host is expired, we don't count it for
3057 hosts_max_retry. This ensures that all hosts must expire before an address
3058 is timed out, unless hosts_max_try_hardlimit (which protects against
3059 lunatic DNS configurations) is reached.
3061 If the host is not expired and we are about to hit the hosts_max_retry
3062 limit, check to see if there is a subsequent hosts with a different MX
3063 value. If so, make that the next host, and don't count this one. This is a
3064 heuristic to make sure that different MXs do get tried. With a normal kind
3065 of retry rule, they would get tried anyway when the earlier hosts were
3066 delayed, but if the domain has a "retry every time" type of rule - as is
3067 often used for the the very large ISPs, that won't happen. */
3071 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
3075 debug_printf("hosts_max_try limit reached with this host\n");
3076 for (h = host; h != NULL; h = h->next)
3077 if (h->mx != host->mx) break;
3081 unexpired_hosts_tried--;
3082 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
3083 "and will be tried\n");
3087 /* Attempt the delivery. */
3089 total_hosts_tried++;
3090 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
3091 expanded_hosts != NULL, &message_defer, FALSE);
3094 OK => connection made, each address contains its result;
3095 message_defer is set for message-specific defers (when all
3096 recipients are marked defer)
3097 DEFER => there was a non-message-specific delivery problem;
3098 ERROR => there was a problem setting up the arguments for a filter,
3099 or there was a problem with expanding added headers
3102 /* If the result is not OK, there was a non-message-specific problem.
3103 If the result is DEFER, we need to write to the logs saying what happened
3104 for this particular host, except in the case of authentication and TLS
3105 failures, where the log has already been written. If all hosts defer a
3106 general message is written at the end. */
3108 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL &&
3109 first_addr->basic_errno != ERRNO_TLSFAILURE)
3110 write_logs(first_addr, host);
3112 #ifdef EXPERIMENTAL_DBL
3114 dbl_write_defer_log(ob->dbl_host_defer_query, first_addr, host);
3117 /* If STARTTLS was accepted, but there was a failure in setting up the
3118 TLS session (usually a certificate screwup), and the host is not in
3119 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
3120 TLS forcibly turned off. We have to start from scratch with a new SMTP
3121 connection. That's why the retry is done from here, not from within
3122 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
3123 session, so the in-clear transmission after those errors, if permitted,
3124 happens inside smtp_deliver().] */
3127 if (rc == DEFER && first_addr->basic_errno == ERRNO_TLSFAILURE &&
3128 ob->tls_tempfail_tryclear &&
3129 verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
3130 host->address, NULL) != OK)
3132 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
3133 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
3134 first_addr = prepare_addresses(addrlist, host);
3135 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
3136 expanded_hosts != NULL, &message_defer, TRUE);
3137 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
3138 write_logs(first_addr, host);
3139 #ifdef EXPERIMENTAL_DBL
3141 dbl_write_defer_log(ob->dbl_host_defer_query, first_addr, host);
3147 /* Delivery attempt finished */
3149 rs = (rc == OK)? US"OK" : (rc == DEFER)? US"DEFER" : (rc == ERROR)?
3152 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
3153 message_id, host->name, host->address, addrlist->address,
3154 (addrlist->next == NULL)? "" : " (& others)", rs);
3156 /* Release serialization if set up */
3158 if (serialized) enq_end(serialize_key);
3160 /* If the result is DEFER, or if a host retry record is known to exist, we
3161 need to add an item to the retry chain for updating the retry database
3162 at the end of delivery. We only need to add the item to the top address,
3163 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
3164 for any other delivery attempts using the same address. (It is copied into
3165 the unusable tree at the outer level, so even if different address blocks
3166 contain the same address, it still won't get tried again.) */
3168 if (rc == DEFER || retry_host_key != NULL)
3170 int delete_flag = (rc != DEFER)? rf_delete : 0;
3171 if (retry_host_key == NULL)
3173 retry_host_key = ob->retry_include_ip_address?
3174 string_sprintf("T:%S:%s%s", host->name, host->address, pistring) :
3175 string_sprintf("T:%S%s", host->name, pistring);
3178 /* If a delivery of another message over an existing SMTP connection
3179 yields DEFER, we do NOT set up retry data for the host. This covers the
3180 case when there are delays in routing the addresses in the second message
3181 that are so long that the server times out. This is alleviated by not
3182 routing addresses that previously had routing defers when handling an
3183 existing connection, but even so, this case may occur (e.g. if a
3184 previously happily routed address starts giving routing defers). If the
3185 host is genuinely down, another non-continued message delivery will
3186 notice it soon enough. */
3188 if (delete_flag != 0 || !continuing)
3189 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
3191 /* We may have tried an expired host, if its retry time has come; ensure
3192 the status reflects the expiry for the benefit of any other addresses. */
3196 host->status = (host_is_expired)?
3197 hstatus_unusable_expired : hstatus_unusable;
3198 host->why = hwhy_deferred;
3202 /* If message_defer is set (host was OK, but every recipient got deferred
3203 because of some message-specific problem), or if that had happened
3204 previously so that a message retry key exists, add an appropriate item
3205 to the retry chain. Note that if there was a message defer but now there is
3206 a host defer, the message defer record gets deleted. That seems perfectly
3207 reasonable. Also, stop the message from being remembered as waiting
3208 for specific hosts. */
3210 if (message_defer || retry_message_key != NULL)
3212 int delete_flag = message_defer? 0 : rf_delete;
3213 if (retry_message_key == NULL)
3215 retry_message_key = ob->retry_include_ip_address?
3216 string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
3218 string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
3220 retry_add_item(addrlist, retry_message_key,
3221 rf_message | rf_host | delete_flag);
3222 update_waiting = FALSE;
3225 /* Any return other than DEFER (that is, OK or ERROR) means that the
3226 addresses have got their final statuses filled in for this host. In the OK
3227 case, see if any of them are deferred. */
3231 for (addr = addrlist; addr != NULL; addr = addr->next)
3233 if (addr->transport_return == DEFER)
3235 some_deferred = TRUE;
3241 /* If no addresses deferred or the result was ERROR, return. We do this for
3242 ERROR because a failing filter set-up or add_headers expansion is likely to
3243 fail for any host we try. */
3245 if (rc == ERROR || (rc == OK && !some_deferred))
3247 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3248 return TRUE; /* Each address has its status */
3251 /* If the result was DEFER or some individual addresses deferred, let
3252 the loop run to try other hosts with the deferred addresses, except for the
3253 case when we were trying to deliver down an existing channel and failed.
3254 Don't try any other hosts in this case. */
3256 if (continuing) break;
3258 /* If the whole delivery, or some individual addresses, were deferred and
3259 there are more hosts that could be tried, do not count this host towards
3260 the hosts_max_try limit if the age of the message is greater than the
3261 maximum retry time for this host. This means we may try try all hosts,
3262 ignoring the limit, when messages have been around for some time. This is
3263 important because if we don't try all hosts, the address will never time
3264 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
3266 if ((rc == DEFER || some_deferred) && nexthost != NULL)
3269 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
3271 if (retry != NULL && retry->rules != NULL)
3273 retry_rule *last_rule;
3274 for (last_rule = retry->rules;
3275 last_rule->next != NULL;
3276 last_rule = last_rule->next);
3277 timedout = time(NULL) - received_time > last_rule->timeout;
3279 else timedout = TRUE; /* No rule => timed out */
3283 unexpired_hosts_tried--;
3284 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
3285 "hosts_max_try (message older than host's retry time)\n");
3288 } /* End of loop for trying multiple hosts. */
3290 /* This is the end of the loop that repeats iff expired is TRUE and
3291 ob->delay_after_cutoff is FALSE. The second time round we will
3292 try those hosts that haven't been tried since the message arrived. */
3296 debug_printf("all IP addresses skipped or deferred at least one address\n");
3297 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
3298 debug_printf("retrying IP addresses not tried since message arrived\n");
3303 /* Get here if all IP addresses are skipped or defer at least one address. In
3304 MUA wrapper mode, this will happen only for connection or other non-message-
3305 specific failures. Force the delivery status for all addresses to FAIL. */
3309 for (addr = addrlist; addr != NULL; addr = addr->next)
3310 addr->transport_return = FAIL;
3314 /* In the normal, non-wrapper case, add a standard message to each deferred
3315 address if there hasn't been an error, that is, if it hasn't actually been
3316 tried this time. The variable "expired" will be FALSE if any deliveries were
3317 actually tried, or if there was at least one host that was not expired. That
3318 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
3319 a delivery has been tried, an error code will be set, and the failing of the
3320 message is handled by the retry code later.
3322 If queue_smtp is set, or this transport was called to send a subsequent message
3323 down an existing TCP/IP connection, and something caused the host not to be
3324 found, we end up here, but can detect these cases and handle them specially. */
3326 for (addr = addrlist; addr != NULL; addr = addr->next)
3328 /* If host is not NULL, it means that we stopped processing the host list
3329 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
3330 means we need to behave as if some hosts were skipped because their retry
3331 time had not come. Specifically, this prevents the address from timing out.
3332 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
3333 hosts were tried. */
3337 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
3340 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
3341 "hosts were tried\n");
3346 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
3347 setflag(addr, af_retry_skipped);
3351 if (queue_smtp) /* no deliveries attempted */
3353 addr->transport_return = DEFER;
3354 addr->basic_errno = 0;
3355 addr->message = US"SMTP delivery explicitly queued";
3358 else if (addr->transport_return == DEFER &&
3359 (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0) &&
3360 addr->message == NULL)
3362 addr->basic_errno = ERRNO_HRETRY;
3363 if (continue_hostname != NULL)
3365 addr->message = US"no host found for existing SMTP connection";
3369 setflag(addr, af_pass_message); /* This is not a security risk */
3370 addr->message = (ob->delay_after_cutoff)?
3371 US"retry time not reached for any host after a long failure period" :
3372 US"all hosts have been failing for a long time and were last tried "
3373 "after this message arrived";
3375 /* If we are already using fallback hosts, or there are no fallback hosts
3376 defined, convert the result to FAIL to cause a bounce. */
3378 if (addr->host_list == addr->fallback_hosts ||
3379 addr->fallback_hosts == NULL)
3380 addr->transport_return = FAIL;
3384 if (hosts_retry == hosts_total)
3385 addr->message = US"retry time not reached for any host";
3386 else if (hosts_fail == hosts_total)
3387 addr->message = US"all host address lookups failed permanently";
3388 else if (hosts_defer == hosts_total)
3389 addr->message = US"all host address lookups failed temporarily";
3390 else if (hosts_serial == hosts_total)
3391 addr->message = US"connection limit reached for all hosts";
3392 else if (hosts_fail+hosts_defer == hosts_total)
3393 addr->message = US"all host address lookups failed";
3394 else addr->message = US"some host address lookups failed and retry time "
3395 "not reached for other hosts or connection limit reached";
3400 /* Update the database which keeps information about which messages are waiting
3401 for which hosts to become available. For some message-specific errors, the
3402 update_waiting flag is turned off because we don't want follow-on deliveries in
3403 those cases. If this transport instance is explicitly limited to one message
3404 per connection then follow-on deliveries are not possible and there's no need
3405 to create/update the per-transport wait-<transport_name> database. */
3407 if (update_waiting && tblock->connection_max_messages != 1)
3408 transport_update_waiting(hostlist, tblock->name);
3412 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3414 return TRUE; /* Each address has its status */
3417 /* End of transport/smtp.c */