c5908641effd43518cd865c31f1752a936659bce
[exim.git] / src / src / transports / smtp.c
1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
4
5 /* Copyright (c) University of Cambridge 1995 - 2017 */
6 /* See the file NOTICE for conditions of use and distribution. */
7
8 #include "../exim.h"
9 #include "smtp.h"
10
11
12 /* Options specific to the smtp transport. This transport also supports LMTP
13 over TCP/IP. The options must be in alphabetic order (note that "_" comes
14 before the lower case letters). Some live in the transport_instance block so as
15 to be publicly visible; these are flagged with opt_public. */
16
17 optionlist smtp_transport_options[] = {
18 { "*expand_multi_domain", opt_stringptr | opt_hidden | opt_public,
19 (void *)offsetof(transport_instance, expand_multi_domain) },
20 { "*expand_retry_include_ip_address", opt_stringptr | opt_hidden,
21 (void *)(offsetof(smtp_transport_options_block, expand_retry_include_ip_address)) },
22
23 { "address_retry_include_sender", opt_bool,
24 (void *)offsetof(smtp_transport_options_block, address_retry_include_sender) },
25 { "allow_localhost", opt_bool,
26 (void *)offsetof(smtp_transport_options_block, allow_localhost) },
27 { "authenticated_sender", opt_stringptr,
28 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
29 { "authenticated_sender_force", opt_bool,
30 (void *)offsetof(smtp_transport_options_block, authenticated_sender_force) },
31 { "command_timeout", opt_time,
32 (void *)offsetof(smtp_transport_options_block, command_timeout) },
33 { "connect_timeout", opt_time,
34 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
35 { "connection_max_messages", opt_int | opt_public,
36 (void *)offsetof(transport_instance, connection_max_messages) },
37 { "data_timeout", opt_time,
38 (void *)offsetof(smtp_transport_options_block, data_timeout) },
39 { "delay_after_cutoff", opt_bool,
40 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
41 #ifndef DISABLE_DKIM
42 { "dkim_canon", opt_stringptr,
43 (void *)offsetof(smtp_transport_options_block, dkim.dkim_canon) },
44 { "dkim_domain", opt_stringptr,
45 (void *)offsetof(smtp_transport_options_block, dkim.dkim_domain) },
46 { "dkim_private_key", opt_stringptr,
47 (void *)offsetof(smtp_transport_options_block, dkim.dkim_private_key) },
48 { "dkim_selector", opt_stringptr,
49 (void *)offsetof(smtp_transport_options_block, dkim.dkim_selector) },
50 { "dkim_sign_headers", opt_stringptr,
51 (void *)offsetof(smtp_transport_options_block, dkim.dkim_sign_headers) },
52 { "dkim_strict", opt_stringptr,
53 (void *)offsetof(smtp_transport_options_block, dkim.dkim_strict) },
54 #endif
55 { "dns_qualify_single", opt_bool,
56 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
57 { "dns_search_parents", opt_bool,
58 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
59 { "dnssec_request_domains", opt_stringptr,
60 (void *)offsetof(smtp_transport_options_block, dnssec.request) },
61 { "dnssec_require_domains", opt_stringptr,
62 (void *)offsetof(smtp_transport_options_block, dnssec.require) },
63 { "dscp", opt_stringptr,
64 (void *)offsetof(smtp_transport_options_block, dscp) },
65 { "fallback_hosts", opt_stringptr,
66 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
67 { "final_timeout", opt_time,
68 (void *)offsetof(smtp_transport_options_block, final_timeout) },
69 { "gethostbyname", opt_bool,
70 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
71 { "helo_data", opt_stringptr,
72 (void *)offsetof(smtp_transport_options_block, helo_data) },
73 { "hosts", opt_stringptr,
74 (void *)offsetof(smtp_transport_options_block, hosts) },
75 { "hosts_avoid_esmtp", opt_stringptr,
76 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
77 { "hosts_avoid_pipelining", opt_stringptr,
78 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
79 #ifdef SUPPORT_TLS
80 { "hosts_avoid_tls", opt_stringptr,
81 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
82 #endif
83 { "hosts_max_try", opt_int,
84 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
85 { "hosts_max_try_hardlimit", opt_int,
86 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
87 #ifdef SUPPORT_TLS
88 { "hosts_nopass_tls", opt_stringptr,
89 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
90 #endif
91 { "hosts_override", opt_bool,
92 (void *)offsetof(smtp_transport_options_block, hosts_override) },
93 { "hosts_randomize", opt_bool,
94 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
95 #if defined(SUPPORT_TLS) && !defined(DISABLE_OCSP)
96 { "hosts_request_ocsp", opt_stringptr,
97 (void *)offsetof(smtp_transport_options_block, hosts_request_ocsp) },
98 #endif
99 { "hosts_require_auth", opt_stringptr,
100 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
101 #ifdef SUPPORT_TLS
102 # ifdef EXPERIMENTAL_DANE
103 { "hosts_require_dane", opt_stringptr,
104 (void *)offsetof(smtp_transport_options_block, hosts_require_dane) },
105 # endif
106 # ifndef DISABLE_OCSP
107 { "hosts_require_ocsp", opt_stringptr,
108 (void *)offsetof(smtp_transport_options_block, hosts_require_ocsp) },
109 # endif
110 { "hosts_require_tls", opt_stringptr,
111 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
112 #endif
113 { "hosts_try_auth", opt_stringptr,
114 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
115 { "hosts_try_chunking", opt_stringptr,
116 (void *)offsetof(smtp_transport_options_block, hosts_try_chunking) },
117 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
118 { "hosts_try_dane", opt_stringptr,
119 (void *)offsetof(smtp_transport_options_block, hosts_try_dane) },
120 #endif
121 { "hosts_try_fastopen", opt_stringptr,
122 (void *)offsetof(smtp_transport_options_block, hosts_try_fastopen) },
123 #ifndef DISABLE_PRDR
124 { "hosts_try_prdr", opt_stringptr,
125 (void *)offsetof(smtp_transport_options_block, hosts_try_prdr) },
126 #endif
127 #ifdef SUPPORT_TLS
128 { "hosts_verify_avoid_tls", opt_stringptr,
129 (void *)offsetof(smtp_transport_options_block, hosts_verify_avoid_tls) },
130 #endif
131 { "interface", opt_stringptr,
132 (void *)offsetof(smtp_transport_options_block, interface) },
133 { "keepalive", opt_bool,
134 (void *)offsetof(smtp_transport_options_block, keepalive) },
135 { "lmtp_ignore_quota", opt_bool,
136 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
137 { "max_rcpt", opt_int | opt_public,
138 (void *)offsetof(transport_instance, max_addresses) },
139 { "multi_domain", opt_expand_bool | opt_public,
140 (void *)offsetof(transport_instance, multi_domain) },
141 { "port", opt_stringptr,
142 (void *)offsetof(smtp_transport_options_block, port) },
143 { "protocol", opt_stringptr,
144 (void *)offsetof(smtp_transport_options_block, protocol) },
145 { "retry_include_ip_address", opt_expand_bool,
146 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
147 { "serialize_hosts", opt_stringptr,
148 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
149 { "size_addition", opt_int,
150 (void *)offsetof(smtp_transport_options_block, size_addition) }
151 #ifdef SUPPORT_SOCKS
152 ,{ "socks_proxy", opt_stringptr,
153 (void *)offsetof(smtp_transport_options_block, socks_proxy) }
154 #endif
155 #ifdef SUPPORT_TLS
156 ,{ "tls_certificate", opt_stringptr,
157 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
158 { "tls_crl", opt_stringptr,
159 (void *)offsetof(smtp_transport_options_block, tls_crl) },
160 { "tls_dh_min_bits", opt_int,
161 (void *)offsetof(smtp_transport_options_block, tls_dh_min_bits) },
162 { "tls_privatekey", opt_stringptr,
163 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
164 { "tls_require_ciphers", opt_stringptr,
165 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
166 { "tls_sni", opt_stringptr,
167 (void *)offsetof(smtp_transport_options_block, tls_sni) },
168 { "tls_tempfail_tryclear", opt_bool,
169 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
170 { "tls_try_verify_hosts", opt_stringptr,
171 (void *)offsetof(smtp_transport_options_block, tls_try_verify_hosts) },
172 { "tls_verify_cert_hostnames", opt_stringptr,
173 (void *)offsetof(smtp_transport_options_block,tls_verify_cert_hostnames)},
174 { "tls_verify_certificates", opt_stringptr,
175 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) },
176 { "tls_verify_hosts", opt_stringptr,
177 (void *)offsetof(smtp_transport_options_block, tls_verify_hosts) }
178 #endif
179 };
180
181 /* Size of the options list. An extern variable has to be used so that its
182 address can appear in the tables drtables.c. */
183
184 int smtp_transport_options_count =
185 sizeof(smtp_transport_options)/sizeof(optionlist);
186
187 /* Default private options block for the smtp transport. */
188
189 smtp_transport_options_block smtp_transport_option_defaults = {
190 NULL, /* hosts */
191 NULL, /* fallback_hosts */
192 NULL, /* hostlist */
193 NULL, /* fallback_hostlist */
194 NULL, /* authenticated_sender */
195 US"$primary_hostname", /* helo_data */
196 NULL, /* interface */
197 NULL, /* port */
198 US"smtp", /* protocol */
199 NULL, /* DSCP */
200 NULL, /* serialize_hosts */
201 NULL, /* hosts_try_auth */
202 NULL, /* hosts_require_auth */
203 US"*", /* hosts_try_chunking */
204 #ifdef EXPERIMENTAL_DANE
205 NULL, /* hosts_try_dane */
206 NULL, /* hosts_require_dane */
207 #endif
208 NULL, /* hosts_try_fastopen */
209 #ifndef DISABLE_PRDR
210 US"*", /* hosts_try_prdr */
211 #endif
212 #ifndef DISABLE_OCSP
213 US"*", /* hosts_request_ocsp (except under DANE; tls_client_start()) */
214 NULL, /* hosts_require_ocsp */
215 #endif
216 NULL, /* hosts_require_tls */
217 NULL, /* hosts_avoid_tls */
218 NULL, /* hosts_verify_avoid_tls */
219 NULL, /* hosts_avoid_pipelining */
220 NULL, /* hosts_avoid_esmtp */
221 NULL, /* hosts_nopass_tls */
222 5*60, /* command_timeout */
223 5*60, /* connect_timeout; shorter system default overrides */
224 5*60, /* data timeout */
225 10*60, /* final timeout */
226 1024, /* size_addition */
227 5, /* hosts_max_try */
228 50, /* hosts_max_try_hardlimit */
229 TRUE, /* address_retry_include_sender */
230 FALSE, /* allow_localhost */
231 FALSE, /* authenticated_sender_force */
232 FALSE, /* gethostbyname */
233 TRUE, /* dns_qualify_single */
234 FALSE, /* dns_search_parents */
235 { NULL, NULL }, /* dnssec_domains {request,require} */
236 TRUE, /* delay_after_cutoff */
237 FALSE, /* hosts_override */
238 FALSE, /* hosts_randomize */
239 TRUE, /* keepalive */
240 FALSE, /* lmtp_ignore_quota */
241 NULL, /* expand_retry_include_ip_address */
242 TRUE /* retry_include_ip_address */
243 #ifdef SUPPORT_SOCKS
244 ,NULL /* socks_proxy */
245 #endif
246 #ifdef SUPPORT_TLS
247 ,NULL, /* tls_certificate */
248 NULL, /* tls_crl */
249 NULL, /* tls_privatekey */
250 NULL, /* tls_require_ciphers */
251 NULL, /* tls_sni */
252 US"system", /* tls_verify_certificates */
253 EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
254 /* tls_dh_min_bits */
255 TRUE, /* tls_tempfail_tryclear */
256 NULL, /* tls_verify_hosts */
257 US"*", /* tls_try_verify_hosts */
258 US"*" /* tls_verify_cert_hostnames */
259 #endif
260 #ifndef DISABLE_DKIM
261 , {NULL, /* dkim_canon */
262 NULL, /* dkim_domain */
263 NULL, /* dkim_private_key */
264 NULL, /* dkim_selector */
265 NULL, /* dkim_sign_headers */
266 NULL, /* dkim_strict */
267 FALSE} /* dot_stuffed */
268 #endif
269 };
270
271 /* some DSN flags for use later */
272
273 static int rf_list[] = {rf_notify_never, rf_notify_success,
274 rf_notify_failure, rf_notify_delay };
275
276 static uschar *rf_names[] = { US"NEVER", US"SUCCESS", US"FAILURE", US"DELAY" };
277
278
279
280 /* Local statics */
281
282 static uschar *smtp_command; /* Points to last cmd for error messages */
283 static uschar *mail_command; /* Points to MAIL cmd for error messages */
284 static uschar *data_command = US""; /* Points to DATA cmd for error messages */
285 static BOOL update_waiting; /* TRUE to update the "wait" database */
286 static BOOL pipelining_active; /* current transaction is in pipe mode */
287
288
289 /*************************************************
290 * Setup entry point *
291 *************************************************/
292
293 /* This function is called when the transport is about to be used,
294 but before running it in a sub-process. It is used for two things:
295
296 (1) To set the fallback host list in addresses, when delivering.
297 (2) To pass back the interface, port, protocol, and other options, for use
298 during callout verification.
299
300 Arguments:
301 tblock pointer to the transport instance block
302 addrlist list of addresses about to be transported
303 tf if not NULL, pointer to block in which to return options
304 uid the uid that will be set (not used)
305 gid the gid that will be set (not used)
306 errmsg place for error message (not used)
307
308 Returns: OK always (FAIL, DEFER not used)
309 */
310
311 static int
312 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
313 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
314 {
315 smtp_transport_options_block *ob =
316 (smtp_transport_options_block *)(tblock->options_block);
317
318 errmsg = errmsg; /* Keep picky compilers happy */
319 uid = uid;
320 gid = gid;
321
322 /* Pass back options if required. This interface is getting very messy. */
323
324 if (tf)
325 {
326 tf->interface = ob->interface;
327 tf->port = ob->port;
328 tf->protocol = ob->protocol;
329 tf->hosts = ob->hosts;
330 tf->hosts_override = ob->hosts_override;
331 tf->hosts_randomize = ob->hosts_randomize;
332 tf->gethostbyname = ob->gethostbyname;
333 tf->qualify_single = ob->dns_qualify_single;
334 tf->search_parents = ob->dns_search_parents;
335 tf->helo_data = ob->helo_data;
336 }
337
338 /* Set the fallback host list for all the addresses that don't have fallback
339 host lists, provided that the local host wasn't present in the original host
340 list. */
341
342 if (!testflag(addrlist, af_local_host_removed))
343 for (; addrlist; addrlist = addrlist->next)
344 if (!addrlist->fallback_hosts) addrlist->fallback_hosts = ob->fallback_hostlist;
345
346 return OK;
347 }
348
349
350
351 /*************************************************
352 * Initialization entry point *
353 *************************************************/
354
355 /* Called for each instance, after its options have been read, to
356 enable consistency checks to be done, or anything else that needs
357 to be set up.
358
359 Argument: pointer to the transport instance block
360 Returns: nothing
361 */
362
363 void
364 smtp_transport_init(transport_instance *tblock)
365 {
366 smtp_transport_options_block *ob =
367 (smtp_transport_options_block *)(tblock->options_block);
368
369 /* Retry_use_local_part defaults FALSE if unset */
370
371 if (tblock->retry_use_local_part == TRUE_UNSET)
372 tblock->retry_use_local_part = FALSE;
373
374 /* Set the default port according to the protocol */
375
376 if (ob->port == NULL)
377 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
378 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
379
380 /* Set up the setup entry point, to be called before subprocesses for this
381 transport. */
382
383 tblock->setup = smtp_transport_setup;
384
385 /* Complain if any of the timeouts are zero. */
386
387 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
388 ob->final_timeout <= 0)
389 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
390 "command, data, or final timeout value is zero for %s transport",
391 tblock->name);
392
393 /* If hosts_override is set and there are local hosts, set the global
394 flag that stops verify from showing router hosts. */
395
396 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
397
398 /* If there are any fallback hosts listed, build a chain of host items
399 for them, but do not do any lookups at this time. */
400
401 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
402 }
403
404
405
406
407
408 /*************************************************
409 * Set delivery info into all active addresses *
410 *************************************************/
411
412 /* Only addresses whose status is >= PENDING are relevant. A lesser
413 status means that an address is not currently being processed.
414
415 Arguments:
416 addrlist points to a chain of addresses
417 errno_value to put in each address's errno field
418 msg to put in each address's message field
419 rc to put in each address's transport_return field
420 pass_message if TRUE, set the "pass message" flag in the address
421 host if set, mark addrs as having used this host
422 smtp_greeting from peer
423 helo_response from peer
424
425 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
426 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
427 this particular type of timeout.
428
429 Returns: nothing
430 */
431
432 static void
433 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
434 BOOL pass_message, host_item * host
435 #ifdef EXPERIMENTAL_DSN_INFO
436 , const uschar * smtp_greeting, const uschar * helo_response
437 #endif
438 )
439 {
440 address_item *addr;
441 int orvalue = 0;
442 if (errno_value == ERRNO_CONNECTTIMEOUT)
443 {
444 errno_value = ETIMEDOUT;
445 orvalue = RTEF_CTOUT;
446 }
447 for (addr = addrlist; addr; addr = addr->next)
448 if (addr->transport_return >= PENDING)
449 {
450 addr->basic_errno = errno_value;
451 addr->more_errno |= orvalue;
452 if (msg)
453 {
454 addr->message = msg;
455 if (pass_message) setflag(addr, af_pass_message);
456 }
457 addr->transport_return = rc;
458 if (host)
459 {
460 addr->host_used = host;
461 #ifdef EXPERIMENTAL_DSN_INFO
462 if (smtp_greeting)
463 {uschar * s = Ustrchr(smtp_greeting, '\n'); if (s) *s = '\0';}
464 addr->smtp_greeting = smtp_greeting;
465
466 if (helo_response)
467 {uschar * s = Ustrchr(helo_response, '\n'); if (s) *s = '\0';}
468 addr->helo_response = helo_response;
469 #endif
470 }
471 }
472 }
473
474 static void
475 set_errno_nohost(address_item *addrlist, int errno_value, uschar *msg, int rc,
476 BOOL pass_message)
477 {
478 set_errno(addrlist, errno_value, msg, rc, pass_message, NULL
479 #ifdef EXPERIMENTAL_DSN_INFO
480 , NULL, NULL
481 #endif
482 );
483 }
484
485
486 /*************************************************
487 * Check an SMTP response *
488 *************************************************/
489
490 /* This function is given an errno code and the SMTP response buffer
491 to analyse, together with the host identification for generating messages. It
492 sets an appropriate message and puts the first digit of the response code into
493 the yield variable. If no response was actually read, a suitable digit is
494 chosen.
495
496 Arguments:
497 host the current host, to get its name for messages
498 errno_value pointer to the errno value
499 more_errno from the top address for use with ERRNO_FILTER_FAIL
500 buffer the SMTP response buffer
501 yield where to put a one-digit SMTP response code
502 message where to put an error message
503 pass_message set TRUE if message is an SMTP response
504
505 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
506 */
507
508 static BOOL
509 check_response(host_item *host, int *errno_value, int more_errno,
510 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
511 {
512 uschar * pl = pipelining_active ? US"pipelined " : US"";
513 const uschar * s;
514
515 *yield = '4'; /* Default setting is to give a temporary error */
516
517 switch(*errno_value)
518 {
519 case ETIMEDOUT: /* Handle response timeout */
520 *message = US string_sprintf("SMTP timeout after %s%s",
521 pl, smtp_command);
522 if (transport_count > 0)
523 *message = US string_sprintf("%s (%d bytes written)", *message,
524 transport_count);
525 return FALSE;
526
527 case ERRNO_SMTPFORMAT: /* Handle malformed SMTP response */
528 s = string_printing(buffer);
529 while (isspace(*s)) s++;
530 *message = *s == 0
531 ? string_sprintf("Malformed SMTP reply (an empty line) "
532 "in response to %s%s", pl, smtp_command)
533 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
534 pl, smtp_command, s);
535 return FALSE;
536
537 case ERRNO_FILTER_FAIL: /* Handle a failed filter process error;
538 can't send QUIT as we mustn't end the DATA. */
539 *message = string_sprintf("transport filter process failed (%d)%s",
540 more_errno,
541 more_errno == EX_EXECFAILED ? ": unable to execute command" : "");
542 return FALSE;
543
544 case ERRNO_CHHEADER_FAIL: /* Handle a failed add_headers expansion;
545 can't send QUIT as we mustn't end the DATA. */
546 *message =
547 string_sprintf("failed to expand headers_add or headers_remove: %s",
548 expand_string_message);
549 return FALSE;
550
551 case ERRNO_WRITEINCOMPLETE: /* failure to write a complete data block */
552 *message = string_sprintf("failed to write a data block");
553 return FALSE;
554
555 #ifdef SUPPORT_I18N
556 case ERRNO_UTF8_FWD: /* no advertised SMTPUTF8, for international message */
557 *message = US"utf8 support required but not offered for forwarding";
558 DEBUG(D_deliver|D_transport) debug_printf("%s\n", *message);
559 return TRUE;
560 #endif
561 }
562
563 /* Handle error responses from the remote mailer. */
564
565 if (buffer[0] != 0)
566 {
567 *message = string_sprintf("SMTP error from remote mail server after %s%s: "
568 "%s", pl, smtp_command, s = string_printing(buffer));
569 *pass_message = TRUE;
570 *yield = buffer[0];
571 return TRUE;
572 }
573
574 /* No data was read. If there is no errno, this must be the EOF (i.e.
575 connection closed) case, which causes deferral. An explicit connection reset
576 error has the same effect. Otherwise, put the host's identity in the message,
577 leaving the errno value to be interpreted as well. In all cases, we have to
578 assume the connection is now dead. */
579
580 if (*errno_value == 0 || *errno_value == ECONNRESET)
581 {
582 *errno_value = ERRNO_SMTPCLOSED;
583 *message = US string_sprintf("Remote host closed connection "
584 "in response to %s%s", pl, smtp_command);
585 }
586 else
587 *message = US string_sprintf("%s [%s]", host->name, host->address);
588
589 return FALSE;
590 }
591
592
593
594 /*************************************************
595 * Write error message to logs *
596 *************************************************/
597
598 /* This writes to the main log and to the message log.
599
600 Arguments:
601 addr the address item containing error information
602 host the current host
603
604 Returns: nothing
605 */
606
607 static void
608 write_logs(address_item *addr, host_item *host)
609 {
610 uschar * message = LOGGING(outgoing_port)
611 ? string_sprintf("H=%s [%s]:%d", host->name, host->address,
612 host->port == PORT_NONE ? 25 : host->port)
613 : string_sprintf("H=%s [%s]", host->name, host->address);
614
615 if (addr->message)
616 {
617 message = string_sprintf("%s: %s", message, addr->message);
618 if (addr->basic_errno > 0)
619 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
620 log_write(0, LOG_MAIN, "%s", message);
621 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
622 }
623 else
624 {
625 const uschar * s = exim_errstr(addr->basic_errno);
626 log_write(0, LOG_MAIN, "%s %s", message, s);
627 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), message, s);
628 }
629 }
630
631 static void
632 msglog_line(host_item * host, uschar * message)
633 {
634 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
635 host->name, host->address, message);
636 }
637
638
639
640 #ifndef DISABLE_EVENT
641 /*************************************************
642 * Post-defer action *
643 *************************************************/
644
645 /* This expands an arbitrary per-transport string.
646 It might, for example, be used to write to the database log.
647
648 Arguments:
649 addr the address item containing error information
650 host the current host
651
652 Returns: nothing
653 */
654
655 static void
656 deferred_event_raise(address_item *addr, host_item *host)
657 {
658 uschar * action = addr->transport->event_action;
659 const uschar * save_domain;
660 uschar * save_local;
661
662 if (!action)
663 return;
664
665 save_domain = deliver_domain;
666 save_local = deliver_localpart;
667
668 /*XXX would ip & port already be set up? */
669 deliver_host_address = string_copy(host->address);
670 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
671 event_defer_errno = addr->basic_errno;
672
673 router_name = addr->router->name;
674 transport_name = addr->transport->name;
675 deliver_domain = addr->domain;
676 deliver_localpart = addr->local_part;
677
678 (void) event_raise(action, US"msg:host:defer",
679 addr->message
680 ? addr->basic_errno > 0
681 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
682 : string_copy(addr->message)
683 : addr->basic_errno > 0
684 ? string_copy(US strerror(addr->basic_errno))
685 : NULL);
686
687 deliver_localpart = save_local;
688 deliver_domain = save_domain;
689 router_name = transport_name = NULL;
690 }
691 #endif
692
693 /*************************************************
694 * Synchronize SMTP responses *
695 *************************************************/
696
697 /* This function is called from smtp_deliver() to receive SMTP responses from
698 the server, and match them up with the commands to which they relate. When
699 PIPELINING is not in use, this function is called after every command, and is
700 therefore somewhat over-engineered, but it is simpler to use a single scheme
701 that works both with and without PIPELINING instead of having two separate sets
702 of code.
703
704 The set of commands that are buffered up with pipelining may start with MAIL
705 and may end with DATA; in between are RCPT commands that correspond to the
706 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
707 etc.) are never buffered.
708
709 Errors after MAIL or DATA abort the whole process leaving the response in the
710 buffer. After MAIL, pending responses are flushed, and the original command is
711 re-instated in big_buffer for error messages. For RCPT commands, the remote is
712 permitted to reject some recipient addresses while accepting others. However
713 certain errors clearly abort the whole process. Set the value in
714 transport_return to PENDING_OK if the address is accepted. If there is a
715 subsequent general error, it will get reset accordingly. If not, it will get
716 converted to OK at the end.
717
718 Arguments:
719 sx smtp connection context
720 count the number of responses to read
721 pending_DATA 0 if last command sent was not DATA
722 +1 if previously had a good recipient
723 -1 if not previously had a good recipient
724
725 Returns: 3 if at least one address had 2xx and one had 5xx
726 2 if at least one address had 5xx but none had 2xx
727 1 if at least one host had a 2xx response, but none had 5xx
728 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
729 -1 timeout while reading RCPT response
730 -2 I/O or other non-response error for RCPT
731 -3 DATA or MAIL failed - errno and buffer set
732 */
733
734 static int
735 sync_responses(smtp_context * sx, int count, int pending_DATA)
736 {
737 address_item *addr = sx->sync_addr;
738 smtp_transport_options_block *ob =
739 (smtp_transport_options_block *)sx->tblock->options_block;
740 int yield = 0;
741
742 /* Handle the response for a MAIL command. On error, reinstate the original
743 command in big_buffer for error message use, and flush any further pending
744 responses before returning, except after I/O errors and timeouts. */
745
746 if (sx->pending_MAIL)
747 {
748 count--;
749 if (!smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
750 '2', ob->command_timeout))
751 {
752 DEBUG(D_transport) debug_printf("bad response for MAIL\n");
753 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
754 if (errno == 0 && sx->buffer[0] != 0)
755 {
756 uschar flushbuffer[4096];
757 int save_errno = 0;
758 if (sx->buffer[0] == '4')
759 {
760 save_errno = ERRNO_MAIL4XX;
761 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
762 }
763 while (count-- > 0)
764 {
765 if (!smtp_read_response(&sx->inblock, flushbuffer, sizeof(flushbuffer),
766 '2', ob->command_timeout)
767 && (errno != 0 || flushbuffer[0] == 0))
768 break;
769 }
770 errno = save_errno;
771 }
772
773 if (pending_DATA) count--; /* Number of RCPT responses to come */
774 while (count-- > 0) /* Mark any pending addrs with the host used */
775 {
776 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
777 addr->host_used = sx->host;
778 addr = addr->next;
779 }
780 return -3;
781 }
782 }
783
784 if (pending_DATA) count--; /* Number of RCPT responses to come */
785
786 /* Read and handle the required number of RCPT responses, matching each one up
787 with an address by scanning for the next address whose status is PENDING_DEFER.
788 */
789
790 while (count-- > 0)
791 {
792 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
793
794 /* The address was accepted */
795 addr->host_used = sx->host;
796
797 if (smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
798 '2', ob->command_timeout))
799 {
800 yield |= 1;
801 addr->transport_return = PENDING_OK;
802
803 /* If af_dr_retry_exists is set, there was a routing delay on this address;
804 ensure that any address-specific retry record is expunged. We do this both
805 for the basic key and for the version that also includes the sender. */
806
807 if (testflag(addr, af_dr_retry_exists))
808 {
809 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
810 sender_address);
811 retry_add_item(addr, altkey, rf_delete);
812 retry_add_item(addr, addr->address_retry_key, rf_delete);
813 }
814 }
815
816 /* Timeout while reading the response */
817
818 else if (errno == ETIMEDOUT)
819 {
820 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
821 transport_rcpt_address(addr, sx->tblock->rcpt_include_affixes));
822 set_errno_nohost(sx->first_addr, ETIMEDOUT, message, DEFER, FALSE);
823 retry_add_item(addr, addr->address_retry_key, 0);
824 update_waiting = FALSE;
825 return -1;
826 }
827
828 /* Handle other errors in obtaining an SMTP response by returning -1. This
829 will cause all the addresses to be deferred. Restore the SMTP command in
830 big_buffer for which we are checking the response, so the error message
831 makes sense. */
832
833 else if (errno != 0 || sx->buffer[0] == 0)
834 {
835 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
836 transport_rcpt_address(addr, sx->tblock->rcpt_include_affixes));
837 return -2;
838 }
839
840 /* Handle SMTP permanent and temporary response codes. */
841
842 else
843 {
844 addr->message =
845 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
846 "%s", transport_rcpt_address(addr, sx->tblock->rcpt_include_affixes),
847 string_printing(sx->buffer));
848 setflag(addr, af_pass_message);
849 if (!sx->verify)
850 msglog_line(sx->host, addr->message);
851
852 /* The response was 5xx */
853
854 if (sx->buffer[0] == '5')
855 {
856 addr->transport_return = FAIL;
857 yield |= 2;
858 }
859
860 /* The response was 4xx */
861
862 else
863 {
864 addr->transport_return = DEFER;
865 addr->basic_errno = ERRNO_RCPT4XX;
866 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
867
868 if (!sx->verify)
869 {
870 #ifndef DISABLE_EVENT
871 event_defer_errno = addr->more_errno;
872 msg_event_raise(US"msg:rcpt:host:defer", addr);
873 #endif
874
875 /* Log temporary errors if there are more hosts to be tried.
876 If not, log this last one in the == line. */
877
878 if (sx->host->next)
879 log_write(0, LOG_MAIN, "H=%s [%s]: %s",
880 sx->host->name, sx->host->address, addr->message);
881
882 #ifndef DISABLE_EVENT
883 else
884 msg_event_raise(US"msg:rcpt:defer", addr);
885 #endif
886
887 /* Do not put this message on the list of those waiting for specific
888 hosts, as otherwise it is likely to be tried too often. */
889
890 update_waiting = FALSE;
891
892 /* Add a retry item for the address so that it doesn't get tried again
893 too soon. If address_retry_include_sender is true, add the sender address
894 to the retry key. */
895
896 retry_add_item(addr,
897 ob->address_retry_include_sender
898 ? string_sprintf("%s:<%s>", addr->address_retry_key, sender_address)
899 : addr->address_retry_key,
900 0);
901 }
902 }
903 }
904 } /* Loop for next RCPT response */
905
906 /* Update where to start at for the next block of responses, unless we
907 have already handled all the addresses. */
908
909 if (addr) sx->sync_addr = addr->next;
910
911 /* Handle a response to DATA. If we have not had any good recipients, either
912 previously or in this block, the response is ignored. */
913
914 if (pending_DATA != 0 &&
915 !smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
916 '3', ob->command_timeout))
917 {
918 int code;
919 uschar *msg;
920 BOOL pass_message;
921 if (pending_DATA > 0 || (yield & 1) != 0)
922 {
923 if (errno == 0 && sx->buffer[0] == '4')
924 {
925 errno = ERRNO_DATA4XX;
926 sx->first_addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
927 }
928 return -3;
929 }
930 (void)check_response(sx->host, &errno, 0, sx->buffer, &code, &msg, &pass_message);
931 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
932 "is in use and there were no good recipients\n", msg);
933 }
934
935 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
936 present) received 3xx. If any RCPTs were handled and yielded anything other
937 than 4xx, yield will be set non-zero. */
938
939 return yield;
940 }
941
942
943
944 /* Do the client side of smtp-level authentication */
945 /*
946 Arguments:
947 buffer EHLO response from server (gets overwritten)
948 addrlist chain of potential addresses to deliver
949 host host to deliver to
950 ob transport options
951 ibp, obp comms channel control blocks
952
953 Returns:
954 OK Success, or failed (but not required): global "smtp_authenticated" set
955 DEFER Failed authentication (and was required)
956 ERROR Internal problem
957
958 FAIL_SEND Failed communications - transmit
959 FAIL - response
960 */
961
962 int
963 smtp_auth(uschar *buffer, unsigned bufsize, address_item *addrlist, host_item *host,
964 smtp_transport_options_block *ob, BOOL is_esmtp,
965 smtp_inblock *ibp, smtp_outblock *obp)
966 {
967 int require_auth;
968 uschar *fail_reason = US"server did not advertise AUTH support";
969
970 smtp_authenticated = FALSE;
971 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
972 require_auth = verify_check_given_host(&ob->hosts_require_auth, host);
973
974 if (is_esmtp && !regex_AUTH) regex_AUTH =
975 regex_must_compile(US"\\n250[\\s\\-]AUTH\\s+([\\-\\w\\s]+)(?:\\n|$)",
976 FALSE, TRUE);
977
978 if (is_esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
979 {
980 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
981 expand_nmax = -1; /* reset */
982
983 /* Must not do this check until after we have saved the result of the
984 regex match above. */
985
986 if (require_auth == OK ||
987 verify_check_given_host(&ob->hosts_try_auth, host) == OK)
988 {
989 auth_instance *au;
990 fail_reason = US"no common mechanisms were found";
991
992 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
993
994 /* Scan the configured authenticators looking for one which is configured
995 for use as a client, which is not suppressed by client_condition, and
996 whose name matches an authentication mechanism supported by the server.
997 If one is found, attempt to authenticate by calling its client function.
998 */
999
1000 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1001 {
1002 uschar *p = names;
1003 if (!au->client ||
1004 (au->client_condition != NULL &&
1005 !expand_check_condition(au->client_condition, au->name,
1006 US"client authenticator")))
1007 {
1008 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1009 au->name,
1010 (au->client)? "client_condition is false" :
1011 "not configured as a client");
1012 continue;
1013 }
1014
1015 /* Loop to scan supported server mechanisms */
1016
1017 while (*p != 0)
1018 {
1019 int rc;
1020 int len = Ustrlen(au->public_name);
1021 while (isspace(*p)) p++;
1022
1023 if (strncmpic(au->public_name, p, len) != 0 ||
1024 (p[len] != 0 && !isspace(p[len])))
1025 {
1026 while (*p != 0 && !isspace(*p)) p++;
1027 continue;
1028 }
1029
1030 /* Found data for a listed mechanism. Call its client entry. Set
1031 a flag in the outblock so that data is overwritten after sending so
1032 that reflections don't show it. */
1033
1034 fail_reason = US"authentication attempt(s) failed";
1035 obp->authenticating = TRUE;
1036 rc = (au->info->clientcode)(au, ibp, obp,
1037 ob->command_timeout, buffer, bufsize);
1038 obp->authenticating = FALSE;
1039 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1040 au->name, rc);
1041
1042 /* A temporary authentication failure must hold up delivery to
1043 this host. After a permanent authentication failure, we carry on
1044 to try other authentication methods. If all fail hard, try to
1045 deliver the message unauthenticated unless require_auth was set. */
1046
1047 switch(rc)
1048 {
1049 case OK:
1050 smtp_authenticated = TRUE; /* stops the outer loop */
1051 client_authenticator = au->name;
1052 if (au->set_client_id != NULL)
1053 client_authenticated_id = expand_string(au->set_client_id);
1054 break;
1055
1056 /* Failure after writing a command */
1057
1058 case FAIL_SEND:
1059 return FAIL_SEND;
1060
1061 /* Failure after reading a response */
1062
1063 case FAIL:
1064 if (errno != 0 || buffer[0] != '5') return FAIL;
1065 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1066 au->name, host->name, host->address, buffer);
1067 break;
1068
1069 /* Failure by some other means. In effect, the authenticator
1070 decided it wasn't prepared to handle this case. Typically this
1071 is the result of "fail" in an expansion string. Do we need to
1072 log anything here? Feb 2006: a message is now put in the buffer
1073 if logging is required. */
1074
1075 case CANCELLED:
1076 if (*buffer != 0)
1077 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1078 "authentication H=%s [%s] %s", au->name, host->name,
1079 host->address, buffer);
1080 break;
1081
1082 /* Internal problem, message in buffer. */
1083
1084 case ERROR:
1085 set_errno_nohost(addrlist, ERRNO_AUTHPROB, string_copy(buffer),
1086 DEFER, FALSE);
1087 return ERROR;
1088 }
1089
1090 break; /* If not authenticated, try next authenticator */
1091 } /* Loop for scanning supported server mechanisms */
1092 } /* Loop for further authenticators */
1093 }
1094 }
1095
1096 /* If we haven't authenticated, but are required to, give up. */
1097
1098 if (require_auth == OK && !smtp_authenticated)
1099 {
1100 set_errno_nohost(addrlist, ERRNO_AUTHFAIL,
1101 string_sprintf("authentication required but %s", fail_reason), DEFER,
1102 FALSE);
1103 return DEFER;
1104 }
1105
1106 return OK;
1107 }
1108
1109
1110 /* Construct AUTH appendix string for MAIL TO */
1111 /*
1112 Arguments
1113 buffer to build string
1114 addrlist chain of potential addresses to deliver
1115 ob transport options
1116
1117 Globals smtp_authenticated
1118 client_authenticated_sender
1119 Return True on error, otherwise buffer has (possibly empty) terminated string
1120 */
1121
1122 BOOL
1123 smtp_mail_auth_str(uschar *buffer, unsigned bufsize, address_item *addrlist,
1124 smtp_transport_options_block *ob)
1125 {
1126 uschar *local_authenticated_sender = authenticated_sender;
1127
1128 #ifdef notdef
1129 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n", authenticated_sender, ob->authenticated_sender, smtp_authenticated?"Y":"N");
1130 #endif
1131
1132 if (ob->authenticated_sender != NULL)
1133 {
1134 uschar *new = expand_string(ob->authenticated_sender);
1135 if (new == NULL)
1136 {
1137 if (!expand_string_forcedfail)
1138 {
1139 uschar *message = string_sprintf("failed to expand "
1140 "authenticated_sender: %s", expand_string_message);
1141 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1142 return TRUE;
1143 }
1144 }
1145 else if (new[0] != 0) local_authenticated_sender = new;
1146 }
1147
1148 /* Add the authenticated sender address if present */
1149
1150 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1151 local_authenticated_sender != NULL)
1152 {
1153 string_format(buffer, bufsize, " AUTH=%s",
1154 auth_xtextencode(local_authenticated_sender,
1155 Ustrlen(local_authenticated_sender)));
1156 client_authenticated_sender = string_copy(local_authenticated_sender);
1157 }
1158 else
1159 *buffer= 0;
1160
1161 return FALSE;
1162 }
1163
1164
1165
1166 #ifdef EXPERIMENTAL_DANE
1167 /* Lookup TLSA record for host/port.
1168 Return: OK success with dnssec; DANE mode
1169 DEFER Do not use this host now, may retry later
1170 FAIL_FORCED No TLSA record; DANE not usable
1171 FAIL Do not use this connection
1172 */
1173
1174 int
1175 tlsa_lookup(const host_item * host, dns_answer * dnsa, BOOL dane_required)
1176 {
1177 /* move this out to host.c given the similarity to dns_lookup() ? */
1178 uschar buffer[300];
1179 const uschar * fullname = buffer;
1180
1181 /* TLSA lookup string */
1182 (void)sprintf(CS buffer, "_%d._tcp.%.256s", host->port, host->name);
1183
1184 switch (dns_lookup(dnsa, buffer, T_TLSA, &fullname))
1185 {
1186 case DNS_SUCCEED:
1187 if (!dns_is_secure(dnsa))
1188 {
1189 log_write(0, LOG_MAIN, "DANE error: TLSA lookup not DNSSEC");
1190 return DEFER;
1191 }
1192 return OK;
1193
1194 case DNS_AGAIN:
1195 return DEFER; /* just defer this TLS'd conn */
1196
1197 case DNS_NODATA: /* no TLSA RR for this lookup */
1198 case DNS_NOMATCH: /* no records at all for this lookup */
1199 return dane_required ? FAIL : FAIL_FORCED;
1200
1201 default:
1202 case DNS_FAIL:
1203 return dane_required ? FAIL : DEFER;
1204 }
1205 }
1206 #endif
1207
1208
1209
1210 typedef struct smtp_compare_s
1211 {
1212 uschar *current_sender_address;
1213 struct transport_instance *tblock;
1214 } smtp_compare_t;
1215
1216
1217 /* Create a unique string that identifies this message, it is based on
1218 sender_address, helo_data and tls_certificate if enabled.
1219 */
1220
1221 static uschar *
1222 smtp_local_identity(uschar * sender, struct transport_instance * tblock)
1223 {
1224 address_item * addr1;
1225 uschar * if1 = US"";
1226 uschar * helo1 = US"";
1227 #ifdef SUPPORT_TLS
1228 uschar * tlsc1 = US"";
1229 #endif
1230 uschar * save_sender_address = sender_address;
1231 uschar * local_identity = NULL;
1232 smtp_transport_options_block * ob =
1233 (smtp_transport_options_block *)tblock->options_block;
1234
1235 sender_address = sender;
1236
1237 addr1 = deliver_make_addr (sender, TRUE);
1238 deliver_set_expansions(addr1);
1239
1240 if (ob->interface)
1241 if1 = expand_string(ob->interface);
1242
1243 if (ob->helo_data)
1244 helo1 = expand_string(ob->helo_data);
1245
1246 #ifdef SUPPORT_TLS
1247 if (ob->tls_certificate)
1248 tlsc1 = expand_string(ob->tls_certificate);
1249 local_identity = string_sprintf ("%s^%s^%s", if1, helo1, tlsc1);
1250 #else
1251 local_identity = string_sprintf ("%s^%s", if1, helo1);
1252 #endif
1253
1254 deliver_set_expansions(NULL);
1255 sender_address = save_sender_address;
1256
1257 return local_identity;
1258 }
1259
1260
1261
1262 /* This routine is a callback that is called from transport_check_waiting.
1263 This function will evaluate the incoming message versus the previous
1264 message. If the incoming message is using a different local identity then
1265 we will veto this new message. */
1266
1267 static BOOL
1268 smtp_are_same_identities(uschar * message_id, smtp_compare_t * s_compare)
1269 {
1270 uschar * message_local_identity,
1271 * current_local_identity,
1272 * new_sender_address;
1273
1274 current_local_identity =
1275 smtp_local_identity(s_compare->current_sender_address, s_compare->tblock);
1276
1277 if (!(new_sender_address = deliver_get_sender_address(message_id)))
1278 return 0;
1279
1280 message_local_identity =
1281 smtp_local_identity(new_sender_address, s_compare->tblock);
1282
1283 return Ustrcmp(current_local_identity, message_local_identity) == 0;
1284 }
1285
1286
1287
1288 static uschar
1289 ehlo_response(uschar * buf, uschar checks)
1290 {
1291 size_t bsize = Ustrlen(buf);
1292
1293 #ifdef SUPPORT_TLS
1294 if ( checks & PEER_OFFERED_TLS
1295 && pcre_exec(regex_STARTTLS, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1296 checks &= ~PEER_OFFERED_TLS;
1297 #endif
1298
1299 if ( checks & PEER_OFFERED_IGNQ
1300 && pcre_exec(regex_IGNOREQUOTA, NULL, CS buf, bsize, 0,
1301 PCRE_EOPT, NULL, 0) < 0)
1302 checks &= ~PEER_OFFERED_IGNQ;
1303
1304 if ( checks & PEER_OFFERED_CHUNKING
1305 && pcre_exec(regex_CHUNKING, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1306 checks &= ~PEER_OFFERED_CHUNKING;
1307
1308 #ifndef DISABLE_PRDR
1309 if ( checks & PEER_OFFERED_PRDR
1310 && pcre_exec(regex_PRDR, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1311 checks &= ~PEER_OFFERED_PRDR;
1312 #endif
1313
1314 #ifdef SUPPORT_I18N
1315 if ( checks & PEER_OFFERED_UTF8
1316 && pcre_exec(regex_UTF8, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1317 checks &= ~PEER_OFFERED_UTF8;
1318 #endif
1319
1320 if ( checks & PEER_OFFERED_DSN
1321 && pcre_exec(regex_DSN, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1322 checks &= ~PEER_OFFERED_DSN;
1323
1324 if ( checks & PEER_OFFERED_PIPE
1325 && pcre_exec(regex_PIPELINING, NULL, CS buf, bsize, 0,
1326 PCRE_EOPT, NULL, 0) < 0)
1327 checks &= ~PEER_OFFERED_PIPE;
1328
1329 if ( checks & PEER_OFFERED_SIZE
1330 && pcre_exec(regex_SIZE, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1331 checks &= ~PEER_OFFERED_SIZE;
1332
1333 return checks;
1334 }
1335
1336
1337
1338 /* Callback for emitting a BDAT data chunk header.
1339
1340 If given a nonzero size, first flush any buffered SMTP commands
1341 then emit the command.
1342
1343 Reap previous SMTP command responses if requested.
1344 Reap one SMTP command response if requested.
1345
1346 Returns: OK or ERROR
1347 */
1348
1349 static int
1350 smtp_chunk_cmd_callback(int fd, transport_ctx * tctx,
1351 unsigned chunk_size, unsigned flags)
1352 {
1353 smtp_transport_options_block * ob =
1354 (smtp_transport_options_block *)(tctx->tblock->options_block);
1355 smtp_context * sx = tctx->smtp_context;
1356 int cmd_count = 0;
1357 int prev_cmd_count;
1358
1359 /* Write SMTP chunk header command */
1360
1361 if (chunk_size > 0)
1362 {
1363 if((cmd_count = smtp_write_command(&sx->outblock, FALSE, "BDAT %u%s\r\n",
1364 chunk_size,
1365 flags & tc_chunk_last ? " LAST" : "")
1366 ) < 0) return ERROR;
1367 if (flags & tc_chunk_last)
1368 data_command = string_copy(big_buffer); /* Save for later error message */
1369 }
1370
1371 prev_cmd_count = cmd_count += sx->cmd_count;
1372
1373 /* Reap responses for any previous, but not one we just emitted */
1374
1375 if (chunk_size > 0)
1376 prev_cmd_count--;
1377 if (sx->pending_BDAT)
1378 prev_cmd_count--;
1379
1380 if (flags & tc_reap_prev && prev_cmd_count > 0)
1381 {
1382 DEBUG(D_transport) debug_printf("look for %d responses"
1383 " for previous pipelined cmds\n", prev_cmd_count);
1384
1385 switch(sync_responses(sx, prev_cmd_count, 0))
1386 {
1387 case 1: /* 2xx (only) => OK */
1388 case 3: sx->good_RCPT = TRUE; /* 2xx & 5xx => OK & progress made */
1389 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
1390 case 0: break; /* No 2xx or 5xx, but no probs */
1391
1392 case -1: /* Timeout on RCPT */
1393 default: return ERROR; /* I/O error, or any MAIL/DATA error */
1394 }
1395 cmd_count = 1;
1396 if (!sx->pending_BDAT)
1397 pipelining_active = FALSE;
1398 }
1399
1400 /* Reap response for an outstanding BDAT */
1401
1402 if (sx->pending_BDAT)
1403 {
1404 DEBUG(D_transport) debug_printf("look for one response for BDAT\n");
1405
1406 if (!smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer), '2',
1407 ob->command_timeout))
1408 {
1409 if (errno == 0 && sx->buffer[0] == '4')
1410 {
1411 errno = ERRNO_DATA4XX; /*XXX does this actually get used? */
1412 sx->addrlist->more_errno |=
1413 ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1414 }
1415 return ERROR;
1416 }
1417 cmd_count--;
1418 sx->pending_BDAT = FALSE;
1419 pipelining_active = FALSE;
1420 }
1421 else if (chunk_size > 0)
1422 sx->pending_BDAT = TRUE;
1423
1424
1425 sx->cmd_count = cmd_count;
1426 return OK;
1427 }
1428
1429
1430
1431 /*************************************************
1432 * Make connection for given message *
1433 *************************************************/
1434
1435 /*
1436 Arguments:
1437 ctx connection context
1438 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1439 a second attempt after TLS initialization fails
1440
1441 Returns: OK - the connection was made and the delivery attempted;
1442 fd is set in the conn context, tls_out set up.
1443 DEFER - the connection could not be made, or something failed
1444 while setting up the SMTP session, or there was a
1445 non-message-specific error, such as a timeout.
1446 ERROR - helo_data or add_headers or authenticated_sender is
1447 specified for this transport, and the string failed
1448 to expand
1449 */
1450 int
1451 smtp_setup_conn(smtp_context * sx, BOOL suppress_tls)
1452 {
1453 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1454 dns_answer tlsa_dnsa;
1455 #endif
1456 BOOL pass_message = FALSE;
1457 uschar * message = NULL;
1458 int yield = OK;
1459 int rc;
1460
1461 sx->ob = (smtp_transport_options_block *) sx->tblock->options_block;
1462
1463 sx->lmtp = strcmpic(sx->ob->protocol, US"lmtp") == 0;
1464 sx->smtps = strcmpic(sx->ob->protocol, US"smtps") == 0;
1465 sx->ok = FALSE;
1466 sx->send_rset = TRUE;
1467 sx->send_quit = TRUE;
1468 sx->setting_up = TRUE;
1469 sx->esmtp = TRUE;
1470 sx->esmtp_sent = FALSE;
1471 #ifdef SUPPORT_I18N
1472 sx->utf8_needed = FALSE;
1473 #endif
1474 sx->dsn_all_lasthop = TRUE;
1475 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1476 sx->dane = FALSE;
1477 sx->dane_required = verify_check_given_host(&sx->ob->hosts_require_dane, sx->host) == OK;
1478 #endif
1479
1480 if ((sx->max_rcpt = sx->tblock->max_addresses) == 0) sx->max_rcpt = 999999;
1481 sx->peer_offered = 0;
1482 sx->igquotstr = US"";
1483 if (!sx->helo_data) sx->helo_data = sx->ob->helo_data;
1484 #ifdef EXPERIMENTAL_DSN_INFO
1485 sx->smtp_greeting = NULL;
1486 sx->helo_response = NULL;
1487 #endif
1488
1489 smtp_command = US"initial connection";
1490 sx->buffer[0] = '\0';
1491
1492 /* Set up the buffer for reading SMTP response packets. */
1493
1494 sx->inblock.buffer = sx->inbuffer;
1495 sx->inblock.buffersize = sizeof(sx->inbuffer);
1496 sx->inblock.ptr = sx->inbuffer;
1497 sx->inblock.ptrend = sx->inbuffer;
1498
1499 /* Set up the buffer for holding SMTP commands while pipelining */
1500
1501 sx->outblock.buffer = sx->outbuffer;
1502 sx->outblock.buffersize = sizeof(sx->outbuffer);
1503 sx->outblock.ptr = sx->outbuffer;
1504 sx->outblock.cmd_count = 0;
1505 sx->outblock.authenticating = FALSE;
1506
1507 /* Reset the parameters of a TLS session. */
1508
1509 tls_out.bits = 0;
1510 tls_out.cipher = NULL; /* the one we may use for this transport */
1511 tls_out.ourcert = NULL;
1512 tls_out.peercert = NULL;
1513 tls_out.peerdn = NULL;
1514 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1515 tls_out.sni = NULL;
1516 #endif
1517 tls_out.ocsp = OCSP_NOT_REQ;
1518
1519 /* Flip the legacy TLS-related variables over to the outbound set in case
1520 they're used in the context of the transport. Don't bother resetting
1521 afterward (when being used by a transport) as we're in a subprocess.
1522 For verify, unflipped once the callout is dealt with */
1523
1524 tls_modify_variables(&tls_out);
1525
1526 #ifndef SUPPORT_TLS
1527 if (sx->smtps)
1528 {
1529 set_errno_nohost(sx->addrlist, ERRNO_TLSFAILURE, US"TLS support not available",
1530 DEFER, FALSE);
1531 return ERROR;
1532 }
1533 #endif
1534
1535 /* Make a connection to the host if this isn't a continued delivery, and handle
1536 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
1537 specially so they can be identified for retries. */
1538
1539 if (continue_hostname == NULL)
1540 {
1541 if (sx->verify)
1542 HDEBUG(D_verify) debug_printf("interface=%s port=%d\n", sx->interface, sx->port);
1543
1544 /* This puts port into host->port */
1545 sx->inblock.sock = sx->outblock.sock =
1546 smtp_connect(sx->host, sx->host_af, sx->port, sx->interface,
1547 sx->ob->connect_timeout, sx->tblock);
1548
1549 if (sx->inblock.sock < 0)
1550 {
1551 uschar * msg = NULL;
1552 if (sx->verify)
1553 {
1554 msg = US strerror(errno);
1555 HDEBUG(D_verify) debug_printf("connect: %s\n", msg);
1556 }
1557 set_errno_nohost(sx->addrlist,
1558 errno == ETIMEDOUT ? ERRNO_CONNECTTIMEOUT : errno,
1559 sx->verify ? string_sprintf("could not connect: %s", msg)
1560 : NULL,
1561 DEFER, FALSE);
1562 sx->send_quit = FALSE;
1563 return DEFER;
1564 }
1565
1566 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1567 {
1568 tls_out.dane_verified = FALSE;
1569 tls_out.tlsa_usage = 0;
1570
1571 if (sx->host->dnssec == DS_YES)
1572 {
1573 if( sx->dane_required
1574 || verify_check_given_host(&sx->ob->hosts_try_dane, sx->host) == OK
1575 )
1576 switch (rc = tlsa_lookup(sx->host, &tlsa_dnsa, sx->dane_required))
1577 {
1578 case OK: sx->dane = TRUE; break;
1579 case FAIL_FORCED: break;
1580 default: set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
1581 string_sprintf("DANE error: tlsa lookup %s",
1582 rc == DEFER ? "DEFER" : "FAIL"),
1583 rc, FALSE);
1584 return rc;
1585 }
1586 }
1587 else if (sx->dane_required)
1588 {
1589 set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
1590 string_sprintf("DANE error: %s lookup not DNSSEC", sx->host->name),
1591 FAIL, FALSE);
1592 return FAIL;
1593 }
1594
1595 if (sx->dane)
1596 sx->ob->tls_tempfail_tryclear = FALSE;
1597 }
1598 #endif /*DANE*/
1599
1600 /* Expand the greeting message while waiting for the initial response. (Makes
1601 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1602 delayed till here so that $sending_interface and $sending_port are set. */
1603
1604 if (sx->helo_data)
1605 if (!(sx->helo_data = expand_string(sx->helo_data)))
1606 if (sx->verify)
1607 log_write(0, LOG_MAIN|LOG_PANIC,
1608 "<%s>: failed to expand transport's helo_data value for callout: %s",
1609 sx->addrlist->address, expand_string_message);
1610
1611 #ifdef SUPPORT_I18N
1612 if (sx->helo_data)
1613 {
1614 expand_string_message = NULL;
1615 if ((sx->helo_data = string_domain_utf8_to_alabel(sx->helo_data,
1616 &expand_string_message)),
1617 expand_string_message)
1618 if (sx->verify)
1619 log_write(0, LOG_MAIN|LOG_PANIC,
1620 "<%s>: failed to expand transport's helo_data value for callout: %s",
1621 sx->addrlist->address, expand_string_message);
1622 else
1623 sx->helo_data = NULL;
1624 }
1625 #endif
1626
1627 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1628 is nevertheless a reasonably clean way of programming this kind of logic,
1629 where you want to escape on any error. */
1630
1631 if (!sx->smtps)
1632 {
1633 BOOL good_response;
1634
1635 #ifdef TCP_QUICKACK
1636 (void) setsockopt(sx->inblock.sock, IPPROTO_TCP, TCP_QUICKACK, US &off, sizeof(off));
1637 #endif
1638 good_response = smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
1639 '2', sx->ob->command_timeout);
1640 #ifdef EXPERIMENTAL_DSN_INFO
1641 sx->smtp_greeting = string_copy(sx->buffer);
1642 #endif
1643 if (!good_response) goto RESPONSE_FAILED;
1644
1645 #ifndef DISABLE_EVENT
1646 {
1647 uschar * s;
1648 lookup_dnssec_authenticated = sx->host->dnssec==DS_YES ? US"yes"
1649 : sx->host->dnssec==DS_NO ? US"no" : NULL;
1650 s = event_raise(sx->tblock->event_action, US"smtp:connect", sx->buffer);
1651 if (s)
1652 {
1653 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL,
1654 string_sprintf("deferred by smtp:connect event expansion: %s", s),
1655 DEFER, FALSE);
1656 yield = DEFER;
1657 goto SEND_QUIT;
1658 }
1659 }
1660 #endif
1661
1662 /* Now check if the helo_data expansion went well, and sign off cleanly if
1663 it didn't. */
1664
1665 if (!sx->helo_data)
1666 {
1667 message = string_sprintf("failed to expand helo_data: %s",
1668 expand_string_message);
1669 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1670 yield = DEFER;
1671 goto SEND_QUIT;
1672 }
1673 }
1674
1675 /** Debugging without sending a message
1676 sx->addrlist->transport_return = DEFER;
1677 goto SEND_QUIT;
1678 **/
1679
1680 /* Errors that occur after this point follow an SMTP command, which is
1681 left in big_buffer by smtp_write_command() for use in error messages. */
1682
1683 smtp_command = big_buffer;
1684
1685 /* Tell the remote who we are...
1686
1687 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1688 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1689 greeting is of this form. The assumption was that the far end supports it
1690 properly... but experience shows that there are some that give 5xx responses,
1691 even though the banner includes "ESMTP" (there's a bloody-minded one that
1692 says "ESMTP not spoken here"). Cope with that case.
1693
1694 September 2000: Time has passed, and it seems reasonable now to always send
1695 EHLO at the start. It is also convenient to make the change while installing
1696 the TLS stuff.
1697
1698 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1699 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1700 would be no way to send out the mails, so there is now a host list
1701 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1702 PIPELINING problem as well. Maybe it can also be useful to cure other
1703 problems with broken servers.
1704
1705 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1706 Then somebody tried it with a Microsoft mailer... It seems that all other
1707 mailers use upper case for some reason (the RFC is quite clear about case
1708 independence) so, for peace of mind, I gave in. */
1709
1710 sx->esmtp = verify_check_given_host(&sx->ob->hosts_avoid_esmtp, sx->host) != OK;
1711
1712 /* Alas; be careful, since this goto is not an error-out, so conceivably
1713 we might set data between here and the target which we assume to exist
1714 and be usable. I can see this coming back to bite us. */
1715 #ifdef SUPPORT_TLS
1716 if (sx->smtps)
1717 {
1718 smtp_peer_options |= PEER_OFFERED_TLS;
1719 suppress_tls = FALSE;
1720 sx->ob->tls_tempfail_tryclear = FALSE;
1721 smtp_command = US"SSL-on-connect";
1722 goto TLS_NEGOTIATE;
1723 }
1724 #endif
1725
1726 if (sx->esmtp)
1727 {
1728 if (smtp_write_command(&sx->outblock, FALSE, "%s %s\r\n",
1729 sx->lmtp ? "LHLO" : "EHLO", sx->helo_data) < 0)
1730 goto SEND_FAILED;
1731 sx->esmtp_sent = TRUE;
1732 if (!smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer), '2',
1733 sx->ob->command_timeout))
1734 {
1735 if (errno != 0 || sx->buffer[0] == 0 || sx->lmtp)
1736 {
1737 #ifdef EXPERIMENTAL_DSN_INFO
1738 sx->helo_response = string_copy(sx->buffer);
1739 #endif
1740 goto RESPONSE_FAILED;
1741 }
1742 sx->esmtp = FALSE;
1743 }
1744 #ifdef EXPERIMENTAL_DSN_INFO
1745 sx->helo_response = string_copy(sx->buffer);
1746 #endif
1747 }
1748 else
1749 DEBUG(D_transport)
1750 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1751
1752 if (!sx->esmtp)
1753 {
1754 BOOL good_response;
1755 int n = sizeof(sx->buffer);
1756 uschar * rsp = sx->buffer;
1757
1758 if (sx->esmtp_sent && (n = Ustrlen(sx->buffer)) < sizeof(sx->buffer)/2)
1759 { rsp = sx->buffer + n + 1; n = sizeof(sx->buffer) - n; }
1760
1761 if (smtp_write_command(&sx->outblock, FALSE, "HELO %s\r\n", sx->helo_data) < 0)
1762 goto SEND_FAILED;
1763 good_response = smtp_read_response(&sx->inblock, rsp, n,
1764 '2', sx->ob->command_timeout);
1765 #ifdef EXPERIMENTAL_DSN_INFO
1766 sx->helo_response = string_copy(rsp);
1767 #endif
1768 if (!good_response)
1769 {
1770 /* Handle special logging for a closed connection after HELO
1771 when had previously sent EHLO */
1772
1773 if (rsp != sx->buffer && rsp[0] == 0 && (errno == 0 || errno == ECONNRESET))
1774 {
1775 errno = ERRNO_SMTPCLOSED;
1776 goto EHLOHELO_FAILED;
1777 }
1778 Ustrncpy(sx->buffer, rsp, sizeof(sx->buffer)/2);
1779 goto RESPONSE_FAILED;
1780 }
1781 }
1782
1783 sx->peer_offered = smtp_peer_options = 0;
1784
1785 if (sx->esmtp || sx->lmtp)
1786 {
1787 sx->peer_offered = ehlo_response(sx->buffer,
1788 PEER_OFFERED_TLS /* others checked later */
1789 );
1790
1791 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1792
1793 #ifdef SUPPORT_TLS
1794 smtp_peer_options |= sx->peer_offered & PEER_OFFERED_TLS;
1795 #endif
1796 }
1797 }
1798
1799 /* For continuing deliveries down the same channel, the socket is the standard
1800 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1801 below). Set up the pointer to where subsequent commands will be left, for
1802 error messages. Note that smtp_peer_options will have been
1803 set from the command line if they were set in the process that passed the
1804 connection on. */
1805
1806 /*XXX continue case needs to propagate DSN_INFO, prob. in deliver.c
1807 as the continue goes via transport_pass_socket() and doublefork and exec.
1808 It does not wait. Unclear how we keep separate host's responses
1809 separate - we could match up by host ip+port as a bodge. */
1810
1811 else
1812 {
1813 sx->inblock.sock = sx->outblock.sock = fileno(stdin);
1814 smtp_command = big_buffer;
1815 sx->host->port = sx->port; /* Record the port that was used */
1816 sx->helo_data = NULL; /* ensure we re-expand ob->helo_data */
1817 }
1818
1819 /* If TLS is available on this connection, whether continued or not, attempt to
1820 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1821 send another EHLO - the server may give a different answer in secure mode. We
1822 use a separate buffer for reading the response to STARTTLS so that if it is
1823 negative, the original EHLO data is available for subsequent analysis, should
1824 the client not be required to use TLS. If the response is bad, copy the buffer
1825 for error analysis. */
1826
1827 #ifdef SUPPORT_TLS
1828 if ( smtp_peer_options & PEER_OFFERED_TLS
1829 && !suppress_tls
1830 && verify_check_given_host(&sx->ob->hosts_avoid_tls, sx->host) != OK
1831 && ( !sx->verify
1832 || verify_check_given_host(&sx->ob->hosts_verify_avoid_tls, sx->host) != OK
1833 ) )
1834 {
1835 uschar buffer2[4096];
1836 if (smtp_write_command(&sx->outblock, FALSE, "STARTTLS\r\n") < 0)
1837 goto SEND_FAILED;
1838
1839 /* If there is an I/O error, transmission of this message is deferred. If
1840 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1841 false, we also defer. However, if there is a temporary rejection of STARTTLS
1842 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1843 STARTTLS, we carry on. This means we will try to send the message in clear,
1844 unless the host is in hosts_require_tls (tested below). */
1845
1846 if (!smtp_read_response(&sx->inblock, buffer2, sizeof(buffer2), '2',
1847 sx->ob->command_timeout))
1848 {
1849 if ( errno != 0
1850 || buffer2[0] == 0
1851 || (buffer2[0] == '4' && !sx->ob->tls_tempfail_tryclear)
1852 )
1853 {
1854 Ustrncpy(sx->buffer, buffer2, sizeof(sx->buffer));
1855 sx->buffer[sizeof(sx->buffer)-1] = '\0';
1856 goto RESPONSE_FAILED;
1857 }
1858 }
1859
1860 /* STARTTLS accepted: try to negotiate a TLS session. */
1861
1862 else
1863 TLS_NEGOTIATE:
1864 {
1865 address_item * addr;
1866 uschar * errstr;
1867 int rc = tls_client_start(sx->inblock.sock, sx->host, sx->addrlist, sx->tblock,
1868 # ifdef EXPERIMENTAL_DANE
1869 sx->dane ? &tlsa_dnsa : NULL,
1870 # endif
1871 &errstr);
1872
1873 /* TLS negotiation failed; give an error. From outside, this function may
1874 be called again to try in clear on a new connection, if the options permit
1875 it for this host. */
1876
1877 if (rc != OK)
1878 {
1879 # ifdef EXPERIMENTAL_DANE
1880 if (sx->dane) log_write(0, LOG_MAIN,
1881 "DANE attempt failed; TLS connection to %s [%s]: %s",
1882 sx->host->name, sx->host->address, errstr);
1883 # endif
1884
1885 errno = ERRNO_TLSFAILURE;
1886 message = string_sprintf("TLS session: %s", errstr);
1887 sx->send_quit = FALSE;
1888 goto TLS_FAILED;
1889 }
1890
1891 /* TLS session is set up */
1892
1893 smtp_peer_options_wrap = smtp_peer_options;
1894 for (addr = sx->addrlist; addr; addr = addr->next)
1895 if (addr->transport_return == PENDING_DEFER)
1896 {
1897 addr->cipher = tls_out.cipher;
1898 addr->ourcert = tls_out.ourcert;
1899 addr->peercert = tls_out.peercert;
1900 addr->peerdn = tls_out.peerdn;
1901 addr->ocsp = tls_out.ocsp;
1902 }
1903 }
1904 }
1905
1906 /* if smtps, we'll have smtp_command set to something else; always safe to
1907 reset it here. */
1908 smtp_command = big_buffer;
1909
1910 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1911 helo_data is null, we are dealing with a connection that was passed from
1912 another process, and so we won't have expanded helo_data above. We have to
1913 expand it here. $sending_ip_address and $sending_port are set up right at the
1914 start of the Exim process (in exim.c). */
1915
1916 if (tls_out.active >= 0)
1917 {
1918 char *greeting_cmd;
1919 BOOL good_response;
1920
1921 if (!sx->helo_data && !(sx->helo_data = expand_string(sx->ob->helo_data)))
1922 {
1923 uschar *message = string_sprintf("failed to expand helo_data: %s",
1924 expand_string_message);
1925 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1926 yield = DEFER;
1927 goto SEND_QUIT;
1928 }
1929
1930 /* For SMTPS we need to wait for the initial OK response. */
1931 if (sx->smtps)
1932 {
1933 good_response = smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
1934 '2', sx->ob->command_timeout);
1935 #ifdef EXPERIMENTAL_DSN_INFO
1936 sx->smtp_greeting = string_copy(sx->buffer);
1937 #endif
1938 if (!good_response) goto RESPONSE_FAILED;
1939 }
1940
1941 if (sx->esmtp)
1942 greeting_cmd = "EHLO";
1943 else
1944 {
1945 greeting_cmd = "HELO";
1946 DEBUG(D_transport)
1947 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1948 }
1949
1950 if (smtp_write_command(&sx->outblock, FALSE, "%s %s\r\n",
1951 sx->lmtp ? "LHLO" : greeting_cmd, sx->helo_data) < 0)
1952 goto SEND_FAILED;
1953 good_response = smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
1954 '2', sx->ob->command_timeout);
1955 #ifdef EXPERIMENTAL_DSN_INFO
1956 sx->helo_response = string_copy(sx->buffer);
1957 #endif
1958 if (!good_response) goto RESPONSE_FAILED;
1959 smtp_peer_options = 0;
1960 }
1961
1962 /* If the host is required to use a secure channel, ensure that we
1963 have one. */
1964
1965 else if ( sx->smtps
1966 # ifdef EXPERIMENTAL_DANE
1967 || sx->dane
1968 # endif
1969 || verify_check_given_host(&sx->ob->hosts_require_tls, sx->host) == OK
1970 )
1971 {
1972 errno = ERRNO_TLSREQUIRED;
1973 message = string_sprintf("a TLS session is required, but %s",
1974 smtp_peer_options & PEER_OFFERED_TLS
1975 ? "an attempt to start TLS failed" : "the server did not offer TLS support");
1976 goto TLS_FAILED;
1977 }
1978 #endif /*SUPPORT_TLS*/
1979
1980 /* If TLS is active, we have just started it up and re-done the EHLO command,
1981 so its response needs to be analyzed. If TLS is not active and this is a
1982 continued session down a previously-used socket, we haven't just done EHLO, so
1983 we skip this. */
1984
1985 if (continue_hostname == NULL
1986 #ifdef SUPPORT_TLS
1987 || tls_out.active >= 0
1988 #endif
1989 )
1990 {
1991 if (sx->esmtp || sx->lmtp)
1992 {
1993 sx->peer_offered = ehlo_response(sx->buffer,
1994 0 /* no TLS */
1995 | (sx->lmtp && sx->ob->lmtp_ignore_quota ? PEER_OFFERED_IGNQ : 0)
1996 | PEER_OFFERED_CHUNKING
1997 | PEER_OFFERED_PRDR
1998 #ifdef SUPPORT_I18N
1999 | (sx->addrlist->prop.utf8_msg ? PEER_OFFERED_UTF8 : 0)
2000 /*XXX if we hand peercaps on to continued-conn processes,
2001 must not depend on this addr */
2002 #endif
2003 | PEER_OFFERED_DSN
2004 | PEER_OFFERED_PIPE
2005 | (sx->ob->size_addition >= 0 ? PEER_OFFERED_SIZE : 0)
2006 );
2007
2008 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
2009 lmtp_ignore_quota option was set. */
2010
2011 sx->igquotstr = sx->peer_offered & PEER_OFFERED_IGNQ ? US" IGNOREQUOTA" : US"";
2012
2013 /* If the response to EHLO specified support for the SIZE parameter, note
2014 this, provided size_addition is non-negative. */
2015
2016 smtp_peer_options |= sx->peer_offered & PEER_OFFERED_SIZE;
2017
2018 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
2019 the current host, esmtp will be false, so PIPELINING can never be used. If
2020 the current host matches hosts_avoid_pipelining, don't do it. */
2021
2022 if ( sx->peer_offered & PEER_OFFERED_PIPE
2023 && verify_check_given_host(&sx->ob->hosts_avoid_pipelining, sx->host) != OK)
2024 smtp_peer_options |= PEER_OFFERED_PIPE;
2025
2026 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
2027 smtp_peer_options & PEER_OFFERED_PIPE ? "" : "not ");
2028
2029 if ( sx->peer_offered & PEER_OFFERED_CHUNKING
2030 && verify_check_given_host(&sx->ob->hosts_try_chunking, sx->host) != OK)
2031 sx->peer_offered &= ~PEER_OFFERED_CHUNKING;
2032
2033 if (sx->peer_offered & PEER_OFFERED_CHUNKING)
2034 {DEBUG(D_transport) debug_printf("CHUNKING usable\n");}
2035
2036 #ifndef DISABLE_PRDR
2037 if ( sx->peer_offered & PEER_OFFERED_PRDR
2038 && verify_check_given_host(&sx->ob->hosts_try_prdr, sx->host) != OK)
2039 sx->peer_offered &= ~PEER_OFFERED_PRDR;
2040
2041 if (sx->peer_offered & PEER_OFFERED_PRDR)
2042 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
2043 #endif
2044
2045 /* Note if the server supports DSN */
2046 smtp_peer_options |= sx->peer_offered & PEER_OFFERED_DSN;
2047 DEBUG(D_transport) debug_printf("%susing DSN\n",
2048 sx->peer_offered & PEER_OFFERED_DSN ? "" : "not ");
2049
2050 /* Note if the response to EHLO specifies support for the AUTH extension.
2051 If it has, check that this host is one we want to authenticate to, and do
2052 the business. The host name and address must be available when the
2053 authenticator's client driver is running. */
2054
2055 switch (yield = smtp_auth(sx->buffer, sizeof(sx->buffer), sx->addrlist, sx->host,
2056 sx->ob, sx->esmtp, &sx->inblock, &sx->outblock))
2057 {
2058 default: goto SEND_QUIT;
2059 case OK: break;
2060 case FAIL_SEND: goto SEND_FAILED;
2061 case FAIL: goto RESPONSE_FAILED;
2062 }
2063 }
2064 }
2065 pipelining_active = !!(smtp_peer_options & PEER_OFFERED_PIPE);
2066
2067 /* The setting up of the SMTP call is now complete. Any subsequent errors are
2068 message-specific. */
2069
2070 sx->setting_up = FALSE;
2071
2072 #ifdef SUPPORT_I18N
2073 if (sx->addrlist->prop.utf8_msg)
2074 {
2075 sx->utf8_needed = !sx->addrlist->prop.utf8_downcvt
2076 && !sx->addrlist->prop.utf8_downcvt_maybe;
2077 DEBUG(D_transport) if (!sx->utf8_needed)
2078 debug_printf("utf8: %s downconvert\n",
2079 sx->addrlist->prop.utf8_downcvt ? "mandatory" : "optional");
2080 }
2081
2082 /* If this is an international message we need the host to speak SMTPUTF8 */
2083 if (sx->utf8_needed && !(sx->peer_offered & PEER_OFFERED_UTF8))
2084 {
2085 errno = ERRNO_UTF8_FWD;
2086 goto RESPONSE_FAILED;
2087 }
2088 #endif
2089
2090 return OK;
2091
2092
2093 {
2094 int code;
2095
2096 RESPONSE_FAILED:
2097 message = NULL;
2098 sx->send_quit = check_response(sx->host, &errno, sx->addrlist->more_errno,
2099 sx->buffer, &code, &message, &pass_message);
2100 goto FAILED;
2101
2102 SEND_FAILED:
2103 code = '4';
2104 message = US string_sprintf("send() to %s [%s] failed: %s",
2105 sx->host->name, sx->host->address, strerror(errno));
2106 sx->send_quit = FALSE;
2107 goto FAILED;
2108
2109 /* This label is jumped to directly when a TLS negotiation has failed,
2110 or was not done for a host for which it is required. Values will be set
2111 in message and errno, and setting_up will always be true. Treat as
2112 a temporary error. */
2113
2114 EHLOHELO_FAILED:
2115 code = '4';
2116 message = string_sprintf("Remote host closed connection in response to %s"
2117 " (EHLO response was: %s)", smtp_command, sx->buffer);
2118 sx->send_quit = FALSE;
2119 goto FAILED;
2120
2121 #ifdef SUPPORT_TLS
2122 TLS_FAILED:
2123 code = '4';
2124 goto FAILED;
2125 #endif
2126
2127 /* The failure happened while setting up the call; see if the failure was
2128 a 5xx response (this will either be on connection, or following HELO - a 5xx
2129 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
2130 never going to accept them. For other errors during setting up (timeouts or
2131 whatever), defer all addresses, and yield DEFER, so that the host is not
2132 tried again for a while. */
2133
2134 FAILED:
2135 sx->ok = FALSE; /* For when reached by GOTO */
2136
2137 yield = code == '5'
2138 #ifdef SUPPORT_I18N
2139 || errno == ERRNO_UTF8_FWD
2140 #endif
2141 ? FAIL : DEFER;
2142
2143 set_errno(sx->addrlist, errno, message, yield, pass_message, sx->host
2144 #ifdef EXPERIMENTAL_DSN_INFO
2145 , sx->smtp_greeting, sx->helo_response
2146 #endif
2147 );
2148 }
2149
2150
2151 SEND_QUIT:
2152
2153 if (sx->send_quit)
2154 (void)smtp_write_command(&sx->outblock, FALSE, "QUIT\r\n");
2155
2156 #ifdef SUPPORT_TLS
2157 tls_close(FALSE, TRUE);
2158 #endif
2159
2160 /* Close the socket, and return the appropriate value, first setting
2161 works because the NULL setting is passed back to the calling process, and
2162 remote_max_parallel is forced to 1 when delivering over an existing connection,
2163
2164 If all went well and continue_more is set, we shouldn't actually get here if
2165 there are further addresses, as the return above will be taken. However,
2166 writing RSET might have failed, or there may be other addresses whose hosts are
2167 specified in the transports, and therefore not visible at top level, in which
2168 case continue_more won't get set. */
2169
2170 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
2171 if (sx->send_quit)
2172 {
2173 shutdown(sx->outblock.sock, SHUT_WR);
2174 if (fcntl(sx->inblock.sock, F_SETFL, O_NONBLOCK) == 0)
2175 for (rc = 16; read(sx->inblock.sock, sx->inbuffer, sizeof(sx->inbuffer)) > 0 && rc > 0;)
2176 rc--; /* drain socket */
2177 sx->send_quit = FALSE;
2178 }
2179 (void)close(sx->inblock.sock);
2180 sx->inblock.sock = sx->outblock.sock = -1;
2181
2182 #ifndef DISABLE_EVENT
2183 (void) event_raise(sx->tblock->event_action, US"tcp:close", NULL);
2184 #endif
2185
2186 continue_transport = NULL;
2187 continue_hostname = NULL;
2188 return yield;
2189 }
2190
2191
2192
2193
2194 /* Create the string of options that will be appended to the MAIL FROM:
2195 in the connection context buffer */
2196
2197 static int
2198 build_mailcmd_options(smtp_context * sx, address_item * addrlist)
2199 {
2200 uschar * p = sx->buffer;
2201 address_item * addr;
2202 int address_count;
2203
2204 *p = 0;
2205
2206 /* If we know the receiving MTA supports the SIZE qualification,
2207 send it, adding something to the message size to allow for imprecision
2208 and things that get added en route. Exim keeps the number of lines
2209 in a message, so we can give an accurate value for the original message, but we
2210 need some additional to handle added headers. (Double "." characters don't get
2211 included in the count.) */
2212
2213 if (sx->peer_offered & PEER_OFFERED_SIZE)
2214 {
2215 sprintf(CS p, " SIZE=%d", message_size+message_linecount+sx->ob->size_addition);
2216 while (*p) p++;
2217 }
2218
2219 #ifndef DISABLE_PRDR
2220 /* If it supports Per-Recipient Data Reponses, and we have omre than one recipient,
2221 request that */
2222
2223 sx->prdr_active = FALSE;
2224 if (sx->peer_offered & PEER_OFFERED_PRDR)
2225 for (addr = addrlist; addr; addr = addr->next)
2226 if (addr->transport_return == PENDING_DEFER)
2227 {
2228 for (addr = addr->next; addr; addr = addr->next)
2229 if (addr->transport_return == PENDING_DEFER)
2230 { /* at least two recipients to send */
2231 sx->prdr_active = TRUE;
2232 sprintf(CS p, " PRDR"); p += 5;
2233 break;
2234 }
2235 break;
2236 }
2237 #endif
2238
2239 #ifdef SUPPORT_I18N
2240 /* If it supports internationalised messages, and this meesage need that,
2241 request it */
2242
2243 if ( sx->peer_offered & PEER_OFFERED_UTF8
2244 && addrlist->prop.utf8_msg
2245 && !addrlist->prop.utf8_downcvt
2246 )
2247 Ustrcpy(p, " SMTPUTF8"), p += 9;
2248 #endif
2249
2250 /* check if all addresses have DSN-lasthop flag; do not send RET and ENVID if so */
2251 for (sx->dsn_all_lasthop = TRUE, addr = addrlist, address_count = 0;
2252 addr && address_count < sx->max_rcpt;
2253 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
2254 {
2255 address_count++;
2256 if (!(addr->dsn_flags & rf_dsnlasthop))
2257 {
2258 sx->dsn_all_lasthop = FALSE;
2259 break;
2260 }
2261 }
2262
2263 /* Add any DSN flags to the mail command */
2264
2265 if (sx->peer_offered & PEER_OFFERED_DSN && !sx->dsn_all_lasthop)
2266 {
2267 if (dsn_ret == dsn_ret_hdrs)
2268 { Ustrcpy(p, " RET=HDRS"); p += 9; }
2269 else if (dsn_ret == dsn_ret_full)
2270 { Ustrcpy(p, " RET=FULL"); p += 9; }
2271
2272 if (dsn_envid)
2273 {
2274 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ENVID=%s", dsn_envid);
2275 while (*p) p++;
2276 }
2277 }
2278
2279 /* If an authenticated_sender override has been specified for this transport
2280 instance, expand it. If the expansion is forced to fail, and there was already
2281 an authenticated_sender for this message, the original value will be used.
2282 Other expansion failures are serious. An empty result is ignored, but there is
2283 otherwise no check - this feature is expected to be used with LMTP and other
2284 cases where non-standard addresses (e.g. without domains) might be required. */
2285
2286 if (smtp_mail_auth_str(p, sizeof(sx->buffer) - (p-sx->buffer), addrlist, sx->ob))
2287 return ERROR;
2288
2289 return OK;
2290 }
2291
2292
2293 static void
2294 build_rcptcmd_options(smtp_context * sx, const address_item * addr)
2295 {
2296 uschar * p = sx->buffer;
2297 *p = 0;
2298
2299 /* Add any DSN flags to the rcpt command */
2300
2301 if (sx->peer_offered & PEER_OFFERED_DSN && !(addr->dsn_flags & rf_dsnlasthop))
2302 {
2303 if (addr->dsn_flags & rf_dsnflags)
2304 {
2305 int i;
2306 BOOL first = TRUE;
2307
2308 Ustrcpy(p, " NOTIFY=");
2309 while (*p) p++;
2310 for (i = 0; i < nelem(rf_list); i++) if (addr->dsn_flags & rf_list[i])
2311 {
2312 if (!first) *p++ = ',';
2313 first = FALSE;
2314 Ustrcpy(p, rf_names[i]);
2315 while (*p) p++;
2316 }
2317 }
2318
2319 if (addr->dsn_orcpt)
2320 {
2321 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ORCPT=%s",
2322 addr->dsn_orcpt);
2323 while (*p) p++;
2324 }
2325 }
2326 }
2327
2328
2329
2330 /*
2331 Return:
2332 0 good, rcpt results in addr->transport_return (PENDING_OK, DEFER, FAIL)
2333 -1 MAIL response error
2334 -2 any non-MAIL read i/o error
2335 -3 non-MAIL response timeout
2336 -4 internal error; channel still usable
2337 -5 transmit failed
2338 */
2339
2340 int
2341 smtp_write_mail_and_rcpt_cmds(smtp_context * sx, int * yield)
2342 {
2343 address_item * addr;
2344 int address_count;
2345 int rc;
2346
2347 if (build_mailcmd_options(sx, sx->first_addr) != OK)
2348 {
2349 *yield = ERROR;
2350 return -4;
2351 }
2352
2353 /* From here until we send the DATA command, we can make use of PIPELINING
2354 if the server host supports it. The code has to be able to check the responses
2355 at any point, for when the buffer fills up, so we write it totally generally.
2356 When PIPELINING is off, each command written reports that it has flushed the
2357 buffer. */
2358
2359 sx->pending_MAIL = TRUE; /* The block starts with MAIL */
2360
2361 {
2362 uschar * s = sx->from_addr;
2363 #ifdef SUPPORT_I18N
2364 uschar * errstr = NULL;
2365
2366 /* If we must downconvert, do the from-address here. Remember we had to
2367 for the to-addresses (done below), and also (ugly) for re-doing when building
2368 the delivery log line. */
2369
2370 if ( sx->addrlist->prop.utf8_msg
2371 && (sx->addrlist->prop.utf8_downcvt || !(sx->peer_offered & PEER_OFFERED_UTF8))
2372 )
2373 {
2374 if (s = string_address_utf8_to_alabel(s, &errstr), errstr)
2375 {
2376 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE);
2377 *yield = ERROR;
2378 return -4;
2379 }
2380 setflag(sx->addrlist, af_utf8_downcvt);
2381 }
2382 #endif
2383
2384 rc = smtp_write_command(&sx->outblock, pipelining_active,
2385 "MAIL FROM:<%s>%s\r\n", s, sx->buffer);
2386 }
2387
2388 mail_command = string_copy(big_buffer); /* Save for later error message */
2389
2390 switch(rc)
2391 {
2392 case -1: /* Transmission error */
2393 return -5;
2394
2395 case +1: /* Cmd was sent */
2396 if (!smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer), '2',
2397 sx->ob->command_timeout))
2398 {
2399 if (errno == 0 && sx->buffer[0] == '4')
2400 {
2401 errno = ERRNO_MAIL4XX;
2402 sx->addrlist->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
2403 }
2404 return -1;
2405 }
2406 sx->pending_MAIL = FALSE;
2407 break;
2408
2409 /* otherwise zero: command queued for pipeline */
2410 }
2411
2412 /* Pass over all the relevant recipient addresses for this host, which are the
2413 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
2414 several before we have to read the responses for those seen so far. This
2415 checking is done by a subroutine because it also needs to be done at the end.
2416 Send only up to max_rcpt addresses at a time, leaving next_addr pointing to
2417 the next one if not all are sent.
2418
2419 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
2420 last address because we want to abort if any recipients have any kind of
2421 problem, temporary or permanent. We know that all recipient addresses will have
2422 the PENDING_DEFER status, because only one attempt is ever made, and we know
2423 that max_rcpt will be large, so all addresses will be done at once.
2424
2425 For verify we flush the pipeline after any (the only) rcpt address. */
2426
2427 for (addr = sx->first_addr, address_count = 0;
2428 addr && address_count < sx->max_rcpt;
2429 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
2430 {
2431 int count;
2432 BOOL no_flush;
2433 uschar * rcpt_addr;
2434
2435 addr->dsn_aware = sx->peer_offered & PEER_OFFERED_DSN
2436 ? dsn_support_yes : dsn_support_no;
2437
2438 address_count++;
2439 no_flush = pipelining_active && !sx->verify && (!mua_wrapper || addr->next);
2440
2441 build_rcptcmd_options(sx, addr);
2442
2443 /* Now send the RCPT command, and process outstanding responses when
2444 necessary. After a timeout on RCPT, we just end the function, leaving the
2445 yield as OK, because this error can often mean that there is a problem with
2446 just one address, so we don't want to delay the host. */
2447
2448 rcpt_addr = transport_rcpt_address(addr, sx->tblock->rcpt_include_affixes);
2449
2450 #ifdef SUPPORT_I18N
2451 if ( testflag(sx->addrlist, af_utf8_downcvt)
2452 && !(rcpt_addr = string_address_utf8_to_alabel(rcpt_addr, NULL))
2453 )
2454 {
2455 /*XXX could we use a per-address errstr here? Not fail the whole send? */
2456 errno = ERRNO_EXPANDFAIL;
2457 return -5; /*XXX too harsh? */
2458 }
2459 #endif
2460
2461 count = smtp_write_command(&sx->outblock, no_flush, "RCPT TO:<%s>%s%s\r\n",
2462 rcpt_addr, sx->igquotstr, sx->buffer);
2463
2464 if (count < 0) return -5;
2465 if (count > 0)
2466 {
2467 switch(sync_responses(sx, count, 0))
2468 {
2469 case 3: sx->ok = TRUE; /* 2xx & 5xx => OK & progress made */
2470 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
2471 break;
2472
2473 case 1: sx->ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2474 if (!sx->lmtp) /* can't tell about progress yet */
2475 sx->completed_addr = TRUE;
2476 case 0: /* No 2xx or 5xx, but no probs */
2477 break;
2478
2479 case -1: return -3; /* Timeout on RCPT */
2480 case -2: return -2; /* non-MAIL read i/o error */
2481 default: return -1; /* any MAIL error */
2482 }
2483 sx->pending_MAIL = FALSE; /* Dealt with MAIL */
2484 }
2485 } /* Loop for next address */
2486
2487 sx->next_addr = addr;
2488 return 0;
2489 }
2490
2491
2492 /*************************************************
2493 * Deliver address list to given host *
2494 *************************************************/
2495
2496 /* If continue_hostname is not null, we get here only when continuing to
2497 deliver down an existing channel. The channel was passed as the standard
2498 input. TLS is never active on a passed channel; the previous process always
2499 closes it down before passing the connection on.
2500
2501 Otherwise, we have to make a connection to the remote host, and do the
2502 initial protocol exchange.
2503
2504 When running as an MUA wrapper, if the sender or any recipient is rejected,
2505 temporarily or permanently, we force failure for all recipients.
2506
2507 Arguments:
2508 addrlist chain of potential addresses to deliver; only those whose
2509 transport_return field is set to PENDING_DEFER are currently
2510 being processed; others should be skipped - they have either
2511 been delivered to an earlier host or IP address, or been
2512 failed by one of them.
2513 host host to deliver to
2514 host_af AF_INET or AF_INET6
2515 port default TCP/IP port to use, in host byte order
2516 interface interface to bind to, or NULL
2517 tblock transport instance block
2518 message_defer set TRUE if yield is OK, but all addresses were deferred
2519 because of a non-recipient, non-host failure, that is, a
2520 4xx response to MAIL FROM, DATA, or ".". This is a defer
2521 that is specific to the message.
2522 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
2523 a second attempt after TLS initialization fails
2524
2525 Returns: OK - the connection was made and the delivery attempted;
2526 the result for each address is in its data block.
2527 DEFER - the connection could not be made, or something failed
2528 while setting up the SMTP session, or there was a
2529 non-message-specific error, such as a timeout.
2530 ERROR - a filter command is specified for this transport,
2531 and there was a problem setting it up; OR helo_data
2532 or add_headers or authenticated_sender is specified
2533 for this transport, and the string failed to expand
2534 */
2535
2536 static int
2537 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
2538 uschar *interface, transport_instance *tblock,
2539 BOOL *message_defer, BOOL suppress_tls)
2540 {
2541 address_item *addr;
2542 int yield = OK;
2543 int save_errno;
2544 int rc;
2545 time_t start_delivery_time = time(NULL);
2546
2547 BOOL pass_message = FALSE;
2548 uschar *message = NULL;
2549 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
2550 uschar *p;
2551
2552 smtp_context sx;
2553
2554 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
2555 *message_defer = FALSE;
2556
2557 sx.addrlist = addrlist;
2558 sx.host = host;
2559 sx.host_af = host_af,
2560 sx.port = port;
2561 sx.interface = interface;
2562 sx.helo_data = NULL;
2563 sx.tblock = tblock;
2564 sx.verify = FALSE;
2565
2566 /* Get the channel set up ready for a message (MAIL FROM being the next
2567 SMTP command to send */
2568
2569 if ((rc = smtp_setup_conn(&sx, suppress_tls)) != OK)
2570 return rc;
2571
2572 /* If there is a filter command specified for this transport, we can now
2573 set it up. This cannot be done until the identify of the host is known. */
2574
2575 if (tblock->filter_command)
2576 {
2577 BOOL rc;
2578 uschar fbuf[64];
2579 sprintf(CS fbuf, "%.50s transport", tblock->name);
2580 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
2581 TRUE, DEFER, addrlist, fbuf, NULL);
2582 transport_filter_timeout = tblock->filter_timeout;
2583
2584 /* On failure, copy the error to all addresses, abandon the SMTP call, and
2585 yield ERROR. */
2586
2587 if (!rc)
2588 {
2589 set_errno_nohost(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
2590 FALSE);
2591 yield = ERROR;
2592 goto SEND_QUIT;
2593 }
2594
2595 if ( transport_filter_argv
2596 && *transport_filter_argv
2597 && **transport_filter_argv
2598 && sx.peer_offered & PEER_OFFERED_CHUNKING
2599 )
2600 {
2601 sx.peer_offered &= ~PEER_OFFERED_CHUNKING;
2602 DEBUG(D_transport) debug_printf("CHUNKING not usable due to transport filter\n");
2603 }
2604 }
2605
2606
2607 /* For messages that have more than the maximum number of envelope recipients,
2608 we want to send several transactions down the same SMTP connection. (See
2609 comments in deliver.c as to how this reconciles, heuristically, with
2610 remote_max_parallel.) This optimization was added to Exim after the following
2611 code was already working. The simplest way to put it in without disturbing the
2612 code was to use a goto to jump back to this point when there is another
2613 transaction to handle. */
2614
2615 SEND_MESSAGE:
2616 sx.from_addr = return_path;
2617 sx.first_addr = sx.sync_addr = addrlist;
2618 sx.ok = FALSE;
2619 sx.send_rset = TRUE;
2620 sx.completed_addr = FALSE;
2621
2622
2623 /* Initiate a message transfer. */
2624
2625 switch(smtp_write_mail_and_rcpt_cmds(&sx, &yield))
2626 {
2627 case 0: break;
2628 case -1: case -2: goto RESPONSE_FAILED;
2629 case -3: goto END_OFF;
2630 case -4: goto SEND_QUIT;
2631 default: goto SEND_FAILED;
2632 }
2633
2634 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
2635 permanently or temporarily. We should have flushed and synced after the last
2636 RCPT. */
2637
2638 if (mua_wrapper)
2639 {
2640 address_item *badaddr;
2641 for (badaddr = sx.first_addr; badaddr; badaddr = badaddr->next)
2642 if (badaddr->transport_return != PENDING_OK)
2643 {
2644 /*XXX could we find a better errno than 0 here? */
2645 set_errno_nohost(addrlist, 0, badaddr->message, FAIL,
2646 testflag(badaddr, af_pass_message));
2647 sx.ok = FALSE;
2648 break;
2649 }
2650 }
2651
2652 /* If ok is TRUE, we know we have got at least one good recipient, and must now
2653 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
2654 have a good recipient buffered up if we are pipelining. We don't want to waste
2655 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
2656 are pipelining. The responses are all handled by sync_responses().
2657 If using CHUNKING, do not send a BDAT until we know how big a chunk we want
2658 to send is. */
2659
2660 if ( !(sx.peer_offered & PEER_OFFERED_CHUNKING)
2661 && (sx.ok || (pipelining_active && !mua_wrapper)))
2662 {
2663 int count = smtp_write_command(&sx.outblock, FALSE, "DATA\r\n");
2664
2665 if (count < 0) goto SEND_FAILED;
2666 switch(sync_responses(&sx, count, sx.ok ? +1 : -1))
2667 {
2668 case 3: sx.ok = TRUE; /* 2xx & 5xx => OK & progress made */
2669 case 2: sx.completed_addr = TRUE; /* 5xx (only) => progress made */
2670 break;
2671
2672 case 1: sx.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2673 if (!sx.lmtp) sx.completed_addr = TRUE; /* can't tell about progress yet */
2674 case 0: break; /* No 2xx or 5xx, but no probs */
2675
2676 case -1: goto END_OFF; /* Timeout on RCPT */
2677 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2678 }
2679 pipelining_active = FALSE;
2680 data_command = string_copy(big_buffer); /* Save for later error message */
2681 }
2682
2683 /* If there were no good recipients (but otherwise there have been no
2684 problems), just set ok TRUE, since we have handled address-specific errors
2685 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
2686 for handling the SMTP dot-handling protocol, flagging to apply to headers as
2687 well as body. Set the appropriate timeout value to be used for each chunk.
2688 (Haven't been able to make it work using select() for writing yet.) */
2689
2690 if (!(sx.peer_offered & PEER_OFFERED_CHUNKING) && !sx.ok)
2691 {
2692 /* Save the first address of the next batch. */
2693 sx.first_addr = sx.next_addr;
2694
2695 sx.ok = TRUE;
2696 }
2697 else
2698 {
2699 transport_ctx tctx = {
2700 tblock,
2701 addrlist,
2702 US".", US"..", /* Escaping strings */
2703 topt_use_crlf | topt_escape_headers
2704 | (tblock->body_only ? topt_no_headers : 0)
2705 | (tblock->headers_only ? topt_no_body : 0)
2706 | (tblock->return_path_add ? topt_add_return_path : 0)
2707 | (tblock->delivery_date_add ? topt_add_delivery_date : 0)
2708 | (tblock->envelope_to_add ? topt_add_envelope_to : 0)
2709 };
2710
2711 /* If using CHUNKING we need a callback from the generic transport
2712 support to us, for the sending of BDAT smtp commands and the reaping
2713 of responses. The callback needs a whole bunch of state so set up
2714 a transport-context structure to be passed around. */
2715
2716 if (sx.peer_offered & PEER_OFFERED_CHUNKING)
2717 {
2718 tctx.check_string = tctx.escape_string = NULL;
2719 tctx.options |= topt_use_bdat;
2720 tctx.chunk_cb = smtp_chunk_cmd_callback;
2721 sx.pending_BDAT = FALSE;
2722 sx.good_RCPT = sx.ok;
2723 sx.cmd_count = 0;
2724 tctx.smtp_context = &sx;
2725 }
2726 else
2727 tctx.options |= topt_end_dot;
2728
2729 /* Save the first address of the next batch. */
2730 sx.first_addr = sx.next_addr;
2731
2732 /* Responses from CHUNKING commands go in buffer. Otherwise,
2733 there has not been a response. */
2734
2735 sx.buffer[0] = 0;
2736
2737 sigalrm_seen = FALSE;
2738 transport_write_timeout = sx.ob->data_timeout;
2739 smtp_command = US"sending data block"; /* For error messages */
2740 DEBUG(D_transport|D_v)
2741 if (sx.peer_offered & PEER_OFFERED_CHUNKING)
2742 debug_printf(" will write message using CHUNKING\n");
2743 else
2744 debug_printf(" SMTP>> writing message and terminating \".\"\n");
2745 transport_count = 0;
2746
2747 #ifndef DISABLE_DKIM
2748 sx.ok = dkim_transport_write_message(sx.inblock.sock, &tctx, &sx.ob->dkim,
2749 CUSS &message);
2750 #else
2751 sx.ok = transport_write_message(sx.inblock.sock, &tctx, 0);
2752 #endif
2753
2754 /* transport_write_message() uses write() because it is called from other
2755 places to write to non-sockets. This means that under some OS (e.g. Solaris)
2756 it can exit with "Broken pipe" as its error. This really means that the
2757 socket got closed at the far end. */
2758
2759 transport_write_timeout = 0; /* for subsequent transports */
2760
2761 /* Failure can either be some kind of I/O disaster (including timeout),
2762 or the failure of a transport filter or the expansion of added headers.
2763 Or, when CHUNKING, it can be a protocol-detected failure. */
2764
2765 if (!sx.ok)
2766 if (message) goto SEND_FAILED;
2767 else goto RESPONSE_FAILED;
2768
2769 /* We used to send the terminating "." explicitly here, but because of
2770 buffering effects at both ends of TCP/IP connections, you don't gain
2771 anything by keeping it separate, so it might as well go in the final
2772 data buffer for efficiency. This is now done by setting the topt_end_dot
2773 flag above. */
2774
2775 smtp_command = US"end of data";
2776
2777 if (sx.peer_offered & PEER_OFFERED_CHUNKING && sx.cmd_count > 1)
2778 {
2779 /* Reap any outstanding MAIL & RCPT commands, but not a DATA-go-ahead */
2780 switch(sync_responses(&sx, sx.cmd_count-1, 0))
2781 {
2782 case 3: sx.ok = TRUE; /* 2xx & 5xx => OK & progress made */
2783 case 2: sx.completed_addr = TRUE; /* 5xx (only) => progress made */
2784 break;
2785
2786 case 1: sx.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2787 if (!sx.lmtp) sx.completed_addr = TRUE; /* can't tell about progress yet */
2788 case 0: break; /* No 2xx or 5xx, but no probs */
2789
2790 case -1: goto END_OFF; /* Timeout on RCPT */
2791 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2792 }
2793 }
2794
2795 #ifndef DISABLE_PRDR
2796 /* For PRDR we optionally get a partial-responses warning
2797 * followed by the individual responses, before going on with
2798 * the overall response. If we don't get the warning then deal
2799 * with per non-PRDR. */
2800 if(sx.prdr_active)
2801 {
2802 sx.ok = smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer), '3',
2803 sx.ob->final_timeout);
2804 if (!sx.ok && errno == 0) switch(sx.buffer[0])
2805 {
2806 case '2': sx.prdr_active = FALSE;
2807 sx.ok = TRUE;
2808 break;
2809 case '4': errno = ERRNO_DATA4XX;
2810 addrlist->more_errno |=
2811 ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
2812 break;
2813 }
2814 }
2815 else
2816 #endif
2817
2818 /* For non-PRDR SMTP, we now read a single response that applies to the
2819 whole message. If it is OK, then all the addresses have been delivered. */
2820
2821 if (!sx.lmtp)
2822 {
2823 sx.ok = smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer), '2',
2824 sx.ob->final_timeout);
2825 if (!sx.ok && errno == 0 && sx.buffer[0] == '4')
2826 {
2827 errno = ERRNO_DATA4XX;
2828 addrlist->more_errno |= ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
2829 }
2830 }
2831
2832 /* For LMTP, we get back a response for every RCPT command that we sent;
2833 some may be accepted and some rejected. For those that get a response, their
2834 status is fixed; any that are accepted have been handed over, even if later
2835 responses crash - at least, that's how I read RFC 2033.
2836
2837 If all went well, mark the recipient addresses as completed, record which
2838 host/IPaddress they were delivered to, and cut out RSET when sending another
2839 message down the same channel. Write the completed addresses to the journal
2840 now so that they are recorded in case there is a crash of hardware or
2841 software before the spool gets updated. Also record the final SMTP
2842 confirmation if needed (for SMTP only). */
2843
2844 if (sx.ok)
2845 {
2846 int flag = '=';
2847 int delivery_time = (int)(time(NULL) - start_delivery_time);
2848 int len;
2849 uschar *conf = NULL;
2850
2851 sx.send_rset = FALSE;
2852 pipelining_active = FALSE;
2853
2854 /* Set up confirmation if needed - applies only to SMTP */
2855
2856 if (
2857 #ifdef DISABLE_EVENT
2858 LOGGING(smtp_confirmation) &&
2859 #endif
2860 !sx.lmtp
2861 )
2862 {
2863 const uschar *s = string_printing(sx.buffer);
2864 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
2865 conf = (s == sx.buffer)? (uschar *)string_copy(s) : US s;
2866 }
2867
2868 /* Process all transported addresses - for LMTP or PRDR, read a status for
2869 each one. */
2870
2871 for (addr = addrlist; addr != sx.first_addr; addr = addr->next)
2872 {
2873 if (addr->transport_return != PENDING_OK) continue;
2874
2875 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
2876 remaining addresses. Otherwise, it's a return code for just the one
2877 address. For temporary errors, add a retry item for the address so that
2878 it doesn't get tried again too soon. */
2879
2880 #ifndef DISABLE_PRDR
2881 if (sx.lmtp || sx.prdr_active)
2882 #else
2883 if (sx.lmtp)
2884 #endif
2885 {
2886 if (!smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer), '2',
2887 sx.ob->final_timeout))
2888 {
2889 if (errno != 0 || sx.buffer[0] == 0) goto RESPONSE_FAILED;
2890 addr->message = string_sprintf(
2891 #ifndef DISABLE_PRDR
2892 "%s error after %s: %s", sx.prdr_active ? "PRDR":"LMTP",
2893 #else
2894 "LMTP error after %s: %s",
2895 #endif
2896 data_command, string_printing(sx.buffer));
2897 setflag(addr, af_pass_message); /* Allow message to go to user */
2898 if (sx.buffer[0] == '5')
2899 addr->transport_return = FAIL;
2900 else
2901 {
2902 errno = ERRNO_DATA4XX;
2903 addr->more_errno |= ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
2904 addr->transport_return = DEFER;
2905 #ifndef DISABLE_PRDR
2906 if (!sx.prdr_active)
2907 #endif
2908 retry_add_item(addr, addr->address_retry_key, 0);
2909 }
2910 continue;
2911 }
2912 sx.completed_addr = TRUE; /* NOW we can set this flag */
2913 if (LOGGING(smtp_confirmation))
2914 {
2915 const uschar *s = string_printing(sx.buffer);
2916 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
2917 conf = (s == sx.buffer) ? US string_copy(s) : US s;
2918 }
2919 }
2920
2921 /* SMTP, or success return from LMTP for this address. Pass back the
2922 actual host that was used. */
2923
2924 addr->transport_return = OK;
2925 addr->more_errno = delivery_time;
2926 addr->host_used = host;
2927 addr->special_action = flag;
2928 addr->message = conf;
2929 #ifndef DISABLE_PRDR
2930 if (sx.prdr_active) addr->flags |= af_prdr_used;
2931 #endif
2932 if (sx.peer_offered & PEER_OFFERED_CHUNKING) addr->flags |= af_chunking_used;
2933 flag = '-';
2934
2935 #ifndef DISABLE_PRDR
2936 if (!sx.prdr_active)
2937 #endif
2938 {
2939 /* Update the journal. For homonymic addresses, use the base address plus
2940 the transport name. See lots of comments in deliver.c about the reasons
2941 for the complications when homonyms are involved. Just carry on after
2942 write error, as it may prove possible to update the spool file later. */
2943
2944 if (testflag(addr, af_homonym))
2945 sprintf(CS sx.buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2946 else
2947 sprintf(CS sx.buffer, "%.500s\n", addr->unique);
2948
2949 DEBUG(D_deliver) debug_printf("journalling %s\n", sx.buffer);
2950 len = Ustrlen(CS sx.buffer);
2951 if (write(journal_fd, sx.buffer, len) != len)
2952 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2953 "%s: %s", sx.buffer, strerror(errno));
2954 }
2955 }
2956
2957 #ifndef DISABLE_PRDR
2958 if (sx.prdr_active)
2959 {
2960 /* PRDR - get the final, overall response. For any non-success
2961 upgrade all the address statuses. */
2962 sx.ok = smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer), '2',
2963 sx.ob->final_timeout);
2964 if (!sx.ok)
2965 {
2966 if(errno == 0 && sx.buffer[0] == '4')
2967 {
2968 errno = ERRNO_DATA4XX;
2969 addrlist->more_errno |= ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
2970 }
2971 for (addr = addrlist; addr != sx.first_addr; addr = addr->next)
2972 if (sx.buffer[0] == '5' || addr->transport_return == OK)
2973 addr->transport_return = PENDING_OK; /* allow set_errno action */
2974 goto RESPONSE_FAILED;
2975 }
2976
2977 /* Update the journal, or setup retry. */
2978 for (addr = addrlist; addr != sx.first_addr; addr = addr->next)
2979 if (addr->transport_return == OK)
2980 {
2981 if (testflag(addr, af_homonym))
2982 sprintf(CS sx.buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2983 else
2984 sprintf(CS sx.buffer, "%.500s\n", addr->unique);
2985
2986 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s\n", sx.buffer);
2987 len = Ustrlen(CS sx.buffer);
2988 if (write(journal_fd, sx.buffer, len) != len)
2989 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2990 "%s: %s", sx.buffer, strerror(errno));
2991 }
2992 else if (addr->transport_return == DEFER)
2993 retry_add_item(addr, addr->address_retry_key, -2);
2994 }
2995 #endif
2996
2997 /* Ensure the journal file is pushed out to disk. */
2998
2999 if (EXIMfsync(journal_fd) < 0)
3000 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
3001 strerror(errno));
3002 }
3003 }
3004
3005
3006 /* Handle general (not specific to one address) failures here. The value of ok
3007 is used to skip over this code on the falling through case. A timeout causes a
3008 deferral. Other errors may defer or fail according to the response code, and
3009 may set up a special errno value, e.g. after connection chopped, which is
3010 assumed if errno == 0 and there is no text in the buffer. If control reaches
3011 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
3012 the problem is not related to this specific message. */
3013
3014 if (!sx.ok)
3015 {
3016 int code, set_rc;
3017 uschar * set_message;
3018
3019 RESPONSE_FAILED:
3020 {
3021 save_errno = errno;
3022 message = NULL;
3023 sx.send_quit = check_response(host, &save_errno, addrlist->more_errno,
3024 sx.buffer, &code, &message, &pass_message);
3025 goto FAILED;
3026 }
3027
3028 SEND_FAILED:
3029 {
3030 save_errno = errno;
3031 code = '4';
3032 message = string_sprintf("send() to %s [%s] failed: %s",
3033 host->name, host->address, message ? message : US strerror(save_errno));
3034 sx.send_quit = FALSE;
3035 goto FAILED;
3036 }
3037
3038 FAILED:
3039 {
3040 BOOL message_error;
3041
3042 sx.ok = FALSE; /* For when reached by GOTO */
3043 set_message = message;
3044
3045 /* We want to handle timeouts after MAIL or "." and loss of connection after
3046 "." specially. They can indicate a problem with the sender address or with
3047 the contents of the message rather than a real error on the connection. These
3048 cases are treated in the same way as a 4xx response. This next bit of code
3049 does the classification. */
3050
3051 switch(save_errno)
3052 {
3053 case 0:
3054 case ERRNO_MAIL4XX:
3055 case ERRNO_DATA4XX:
3056 message_error = TRUE;
3057 break;
3058
3059 case ETIMEDOUT:
3060 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
3061 Ustrncmp(smtp_command,"end ",4) == 0;
3062 break;
3063
3064 case ERRNO_SMTPCLOSED:
3065 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
3066 break;
3067
3068 default:
3069 message_error = FALSE;
3070 break;
3071 }
3072
3073 /* Handle the cases that are treated as message errors. These are:
3074
3075 (a) negative response or timeout after MAIL
3076 (b) negative response after DATA
3077 (c) negative response or timeout or dropped connection after "."
3078 (d) utf8 support required and not offered
3079
3080 It won't be a negative response or timeout after RCPT, as that is dealt
3081 with separately above. The action in all cases is to set an appropriate
3082 error code for all the addresses, but to leave yield set to OK because the
3083 host itself has not failed. Of course, it might in practice have failed
3084 when we've had a timeout, but if so, we'll discover that at the next
3085 delivery attempt. For a temporary error, set the message_defer flag, and
3086 write to the logs for information if this is not the last host. The error
3087 for the last host will be logged as part of the address's log line. */
3088
3089 if (message_error)
3090 {
3091 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
3092
3093 /* If there's an errno, the message contains just the identity of
3094 the host. */
3095
3096 if (code == '5')
3097 set_rc = FAIL;
3098 else /* Anything other than 5 is treated as temporary */
3099 {
3100 set_rc = DEFER;
3101 if (save_errno > 0)
3102 message = US string_sprintf("%s: %s", message, strerror(save_errno));
3103 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
3104 msglog_line(host, message);
3105 *message_defer = TRUE;
3106 }
3107 }
3108
3109 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
3110 ".", or some other transportation error. We defer all addresses and yield
3111 DEFER, except for the case of failed add_headers expansion, or a transport
3112 filter failure, when the yield should be ERROR, to stop it trying other
3113 hosts. */
3114
3115 else
3116 {
3117 set_rc = DEFER;
3118 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
3119 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
3120 }
3121 }
3122
3123 set_errno(addrlist, save_errno, set_message, set_rc, pass_message, host
3124 #ifdef EXPERIMENTAL_DSN_INFO
3125 , sx.smtp_greeting, sx.helo_response
3126 #endif
3127 );
3128 }
3129
3130
3131 /* If all has gone well, send_quit will be set TRUE, implying we can end the
3132 SMTP session tidily. However, if there were too many addresses to send in one
3133 message (indicated by first_addr being non-NULL) we want to carry on with the
3134 rest of them. Also, it is desirable to send more than one message down the SMTP
3135 connection if there are several waiting, provided we haven't already sent so
3136 many as to hit the configured limit. The function transport_check_waiting looks
3137 for a waiting message and returns its id. Then transport_pass_socket tries to
3138 set up a continued delivery by passing the socket on to another process. The
3139 variable send_rset is FALSE if a message has just been successfully transfered.
3140
3141 If we are already sending down a continued channel, there may be further
3142 addresses not yet delivered that are aimed at the same host, but which have not
3143 been passed in this run of the transport. In this case, continue_more will be
3144 true, and all we should do is send RSET if necessary, and return, leaving the
3145 channel open.
3146
3147 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
3148 do not want to continue with other messages down the same channel, because that
3149 can lead to looping between two or more messages, all with the same,
3150 temporarily failing address(es). [The retry information isn't updated yet, so
3151 new processes keep on trying.] We probably also don't want to try more of this
3152 message's addresses either.
3153
3154 If we have started a TLS session, we have to end it before passing the
3155 connection to a new process. However, not all servers can handle this (Exim
3156 can), so we do not pass such a connection on if the host matches
3157 hosts_nopass_tls. */
3158
3159 DEBUG(D_transport)
3160 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
3161 "yield=%d first_address is %sNULL\n", sx.ok, sx.send_quit,
3162 sx.send_rset, continue_more, yield, sx.first_addr ? "not " : "");
3163
3164 if (sx.completed_addr && sx.ok && sx.send_quit)
3165 {
3166 BOOL more;
3167 smtp_compare_t t_compare;
3168
3169 t_compare.tblock = tblock;
3170 t_compare.current_sender_address = sender_address;
3171
3172 if ( sx.first_addr != NULL
3173 || continue_more
3174 || ( ( tls_out.active < 0
3175 || verify_check_given_host(&sx.ob->hosts_nopass_tls, host) != OK
3176 )
3177 &&
3178 transport_check_waiting(tblock->name, host->name,
3179 tblock->connection_max_messages, new_message_id, &more,
3180 (oicf)smtp_are_same_identities, (void*)&t_compare)
3181 ) )
3182 {
3183 uschar *msg;
3184 BOOL pass_message;
3185
3186 if (sx.send_rset)
3187 if (! (sx.ok = smtp_write_command(&sx.outblock, FALSE, "RSET\r\n") >= 0))
3188 {
3189 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
3190 host->address, strerror(errno));
3191 sx.send_quit = FALSE;
3192 }
3193 else if (! (sx.ok = smtp_read_response(&sx.inblock, sx.buffer,
3194 sizeof(sx.buffer), '2', sx.ob->command_timeout)))
3195 {
3196 int code;
3197 sx.send_quit = check_response(host, &errno, 0, sx.buffer, &code, &msg,
3198 &pass_message);
3199 if (!sx.send_quit)
3200 {
3201 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
3202 host->name, host->address, msg);
3203 }
3204 }
3205
3206 /* Either RSET was not needed, or it succeeded */
3207
3208 if (sx.ok)
3209 {
3210 if (sx.first_addr != NULL) /* More addresses still to be sent */
3211 { /* in this run of the transport */
3212 continue_sequence++; /* Causes * in logging */
3213 goto SEND_MESSAGE;
3214 }
3215 if (continue_more) return yield; /* More addresses for another run */
3216
3217 /* Pass the socket to a new Exim process. Before doing so, we must shut
3218 down TLS. Not all MTAs allow for the continuation of the SMTP session
3219 when TLS is shut down. We test for this by sending a new EHLO. If we
3220 don't get a good response, we don't attempt to pass the socket on. */
3221
3222 #ifdef SUPPORT_TLS
3223 if (tls_out.active >= 0)
3224 {
3225 tls_close(FALSE, TRUE);
3226 smtp_peer_options = smtp_peer_options_wrap;
3227 sx.ok = !sx.smtps
3228 && smtp_write_command(&sx.outblock, FALSE,
3229 "EHLO %s\r\n", sx.helo_data) >= 0
3230 && smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer),
3231 '2', sx.ob->command_timeout);
3232 }
3233 #endif
3234
3235 /* If the socket is successfully passed, we mustn't send QUIT (or
3236 indeed anything!) from here. */
3237
3238 /*XXX DSN_INFO: assume likely to do new HELO; but for greet we'll want to
3239 propagate it from the initial
3240 */
3241 if (sx.ok && transport_pass_socket(tblock->name, host->name,
3242 host->address, new_message_id, sx.inblock.sock))
3243 sx.send_quit = FALSE;
3244 }
3245
3246 /* If RSET failed and there are addresses left, they get deferred. */
3247
3248 else set_errno(sx.first_addr, errno, msg, DEFER, FALSE, host
3249 #ifdef EXPERIMENTAL_DSN_INFO
3250 , sx.smtp_greeting, sx.helo_response
3251 #endif
3252 );
3253 }
3254 }
3255
3256 /* End off tidily with QUIT unless the connection has died or the socket has
3257 been passed to another process. There has been discussion on the net about what
3258 to do after sending QUIT. The wording of the RFC suggests that it is necessary
3259 to wait for a response, but on the other hand, there isn't anything one can do
3260 with an error response, other than log it. Exim used to do that. However,
3261 further discussion suggested that it is positively advantageous not to wait for
3262 the response, but to close the session immediately. This is supposed to move
3263 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
3264 load from the server. (Hosts that are both servers and clients may not see much
3265 difference, of course.) Further discussion indicated that this was safe to do
3266 on Unix systems which have decent implementations of TCP/IP that leave the
3267 connection around for a while (TIME_WAIT) after the application has gone away.
3268 This enables the response sent by the server to be properly ACKed rather than
3269 timed out, as can happen on broken TCP/IP implementations on other OS.
3270
3271 This change is being made on 31-Jul-98. After over a year of trouble-free
3272 operation, the old commented-out code was removed on 17-Sep-99. */
3273
3274 SEND_QUIT:
3275 if (sx.send_quit) (void)smtp_write_command(&sx.outblock, FALSE, "QUIT\r\n");
3276
3277 END_OFF:
3278
3279 #ifdef SUPPORT_TLS
3280 tls_close(FALSE, TRUE);
3281 #endif
3282
3283 /* Close the socket, and return the appropriate value, first setting
3284 works because the NULL setting is passed back to the calling process, and
3285 remote_max_parallel is forced to 1 when delivering over an existing connection,
3286
3287 If all went well and continue_more is set, we shouldn't actually get here if
3288 there are further addresses, as the return above will be taken. However,
3289 writing RSET might have failed, or there may be other addresses whose hosts are
3290 specified in the transports, and therefore not visible at top level, in which
3291 case continue_more won't get set. */
3292
3293 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
3294 if (sx.send_quit)
3295 {
3296 shutdown(sx.outblock.sock, SHUT_WR);
3297 if (fcntl(sx.inblock.sock, F_SETFL, O_NONBLOCK) == 0)
3298 for (rc = 16; read(sx.inblock.sock, sx.inbuffer, sizeof(sx.inbuffer)) > 0 && rc > 0;)
3299 rc--; /* drain socket */
3300 }
3301 (void)close(sx.inblock.sock);
3302
3303 #ifndef DISABLE_EVENT
3304 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
3305 #endif
3306
3307 continue_transport = NULL;
3308 continue_hostname = NULL;
3309 return yield;
3310 }
3311
3312
3313
3314
3315 /*************************************************
3316 * Closedown entry point *
3317 *************************************************/
3318
3319 /* This function is called when exim is passed an open smtp channel
3320 from another incarnation, but the message which it has been asked
3321 to deliver no longer exists. The channel is on stdin.
3322
3323 We might do fancy things like looking for another message to send down
3324 the channel, but if the one we sought has gone, it has probably been
3325 delivered by some other process that itself will seek further messages,
3326 so just close down our connection.
3327
3328 Argument: pointer to the transport instance block
3329 Returns: nothing
3330 */
3331
3332 void
3333 smtp_transport_closedown(transport_instance *tblock)
3334 {
3335 smtp_transport_options_block *ob =
3336 (smtp_transport_options_block *)tblock->options_block;
3337 smtp_inblock inblock;
3338 smtp_outblock outblock;
3339 uschar buffer[256];
3340 uschar inbuffer[4096];
3341 uschar outbuffer[16];
3342
3343 inblock.sock = fileno(stdin);
3344 inblock.buffer = inbuffer;
3345 inblock.buffersize = sizeof(inbuffer);
3346 inblock.ptr = inbuffer;
3347 inblock.ptrend = inbuffer;
3348
3349 outblock.sock = inblock.sock;
3350 outblock.buffersize = sizeof(outbuffer);
3351 outblock.buffer = outbuffer;
3352 outblock.ptr = outbuffer;
3353 outblock.cmd_count = 0;
3354 outblock.authenticating = FALSE;
3355
3356 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
3357 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
3358 ob->command_timeout);
3359 (void)close(inblock.sock);
3360 }
3361
3362
3363
3364 /*************************************************
3365 * Prepare addresses for delivery *
3366 *************************************************/
3367
3368 /* This function is called to flush out error settings from previous delivery
3369 attempts to other hosts. It also records whether we got here via an MX record
3370 or not in the more_errno field of the address. We are interested only in
3371 addresses that are still marked DEFER - others may have got delivered to a
3372 previously considered IP address. Set their status to PENDING_DEFER to indicate
3373 which ones are relevant this time.
3374
3375 Arguments:
3376 addrlist the list of addresses
3377 host the host we are delivering to
3378
3379 Returns: the first address for this delivery
3380 */
3381
3382 static address_item *
3383 prepare_addresses(address_item *addrlist, host_item *host)
3384 {
3385 address_item *first_addr = NULL;
3386 address_item *addr;
3387 for (addr = addrlist; addr; addr = addr->next)
3388 if (addr->transport_return == DEFER)
3389 {
3390 if (!first_addr) first_addr = addr;
3391 addr->transport_return = PENDING_DEFER;
3392 addr->basic_errno = 0;
3393 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
3394 addr->message = NULL;
3395 #ifdef SUPPORT_TLS
3396 addr->cipher = NULL;
3397 addr->ourcert = NULL;
3398 addr->peercert = NULL;
3399 addr->peerdn = NULL;
3400 addr->ocsp = OCSP_NOT_REQ;
3401 #endif
3402 #ifdef EXPERIMENTAL_DSN_INFO
3403 addr->smtp_greeting = NULL;
3404 addr->helo_response = NULL;
3405 #endif
3406 }
3407 return first_addr;
3408 }
3409
3410
3411
3412 /*************************************************
3413 * Main entry point *
3414 *************************************************/
3415
3416 /* See local README for interface details. As this is a remote transport, it is
3417 given a chain of addresses to be delivered in one connection, if possible. It
3418 always returns TRUE, indicating that each address has its own independent
3419 status set, except if there is a setting up problem, in which case it returns
3420 FALSE. */
3421
3422 BOOL
3423 smtp_transport_entry(
3424 transport_instance *tblock, /* data for this instantiation */
3425 address_item *addrlist) /* addresses we are working on */
3426 {
3427 int cutoff_retry;
3428 int port;
3429 int hosts_defer = 0;
3430 int hosts_fail = 0;
3431 int hosts_looked_up = 0;
3432 int hosts_retry = 0;
3433 int hosts_serial = 0;
3434 int hosts_total = 0;
3435 int total_hosts_tried = 0;
3436 address_item *addr;
3437 BOOL expired = TRUE;
3438 uschar *expanded_hosts = NULL;
3439 uschar *pistring;
3440 uschar *tid = string_sprintf("%s transport", tblock->name);
3441 smtp_transport_options_block *ob =
3442 (smtp_transport_options_block *)(tblock->options_block);
3443 host_item *hostlist = addrlist->host_list;
3444 host_item *host = NULL;
3445
3446 DEBUG(D_transport)
3447 {
3448 debug_printf("%s transport entered\n", tblock->name);
3449 for (addr = addrlist; addr; addr = addr->next)
3450 debug_printf(" %s\n", addr->address);
3451 if (hostlist)
3452 {
3453 debug_printf("hostlist:\n");
3454 for (host = hostlist; host; host = host->next)
3455 debug_printf(" %s:%d\n", host->name, host->port);
3456 }
3457 if (continue_hostname) debug_printf("already connected to %s [%s]\n",
3458 continue_hostname, continue_host_address);
3459 }
3460
3461 /* Set the flag requesting that these hosts be added to the waiting
3462 database if the delivery fails temporarily or if we are running with
3463 queue_smtp or a 2-stage queue run. This gets unset for certain
3464 kinds of error, typically those that are specific to the message. */
3465
3466 update_waiting = TRUE;
3467
3468 /* If a host list is not defined for the addresses - they must all have the
3469 same one in order to be passed to a single transport - or if the transport has
3470 a host list with hosts_override set, use the host list supplied with the
3471 transport. It is an error for this not to exist. */
3472
3473 if (!hostlist || (ob->hosts_override && ob->hosts))
3474 {
3475 if (!ob->hosts)
3476 {
3477 addrlist->message = string_sprintf("%s transport called with no hosts set",
3478 tblock->name);
3479 addrlist->transport_return = PANIC;
3480 return FALSE; /* Only top address has status */
3481 }
3482
3483 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
3484 ob->hosts);
3485
3486 /* If the transport's host list contains no '$' characters, and we are not
3487 randomizing, it is fixed and therefore a chain of hosts can be built once
3488 and for all, and remembered for subsequent use by other calls to this
3489 transport. If, on the other hand, the host list does contain '$', or we are
3490 randomizing its order, we have to rebuild it each time. In the fixed case,
3491 as the hosts string will never be used again, it doesn't matter that we
3492 replace all the : characters with zeros. */
3493
3494 if (!ob->hostlist)
3495 {
3496 uschar *s = ob->hosts;
3497
3498 if (Ustrchr(s, '$') != NULL)
3499 {
3500 if (!(expanded_hosts = expand_string(s)))
3501 {
3502 addrlist->message = string_sprintf("failed to expand list of hosts "
3503 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
3504 addrlist->transport_return = search_find_defer ? DEFER : PANIC;
3505 return FALSE; /* Only top address has status */
3506 }
3507 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
3508 "\"%s\"\n", s, expanded_hosts);
3509 s = expanded_hosts;
3510 }
3511 else
3512 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
3513
3514 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
3515
3516 /* Check that the expansion yielded something useful. */
3517 if (!hostlist)
3518 {
3519 addrlist->message =
3520 string_sprintf("%s transport has empty hosts setting", tblock->name);
3521 addrlist->transport_return = PANIC;
3522 return FALSE; /* Only top address has status */
3523 }
3524
3525 /* If there was no expansion of hosts, save the host list for
3526 next time. */
3527
3528 if (!expanded_hosts) ob->hostlist = hostlist;
3529 }
3530
3531 /* This is not the first time this transport has been run in this delivery;
3532 the host list was built previously. */
3533
3534 else
3535 hostlist = ob->hostlist;
3536 }
3537
3538 /* The host list was supplied with the address. If hosts_randomize is set, we
3539 must sort it into a random order if it did not come from MX records and has not
3540 already been randomized (but don't bother if continuing down an existing
3541 connection). */
3542
3543 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continue_hostname)
3544 {
3545 host_item *newlist = NULL;
3546 while (hostlist)
3547 {
3548 host_item *h = hostlist;
3549 hostlist = hostlist->next;
3550
3551 h->sort_key = random_number(100);
3552
3553 if (!newlist)
3554 {
3555 h->next = NULL;
3556 newlist = h;
3557 }
3558 else if (h->sort_key < newlist->sort_key)
3559 {
3560 h->next = newlist;
3561 newlist = h;
3562 }
3563 else
3564 {
3565 host_item *hh = newlist;
3566 while (hh->next)
3567 {
3568 if (h->sort_key < hh->next->sort_key) break;
3569 hh = hh->next;
3570 }
3571 h->next = hh->next;
3572 hh->next = h;
3573 }
3574 }
3575
3576 hostlist = addrlist->host_list = newlist;
3577 }
3578
3579 /* Sort out the default port. */
3580
3581 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
3582
3583 /* For each host-plus-IP-address on the list:
3584
3585 . If this is a continued delivery and the host isn't the one with the
3586 current connection, skip.
3587
3588 . If the status is unusable (i.e. previously failed or retry checked), skip.
3589
3590 . If no IP address set, get the address, either by turning the name into
3591 an address, calling gethostbyname if gethostbyname is on, or by calling
3592 the DNS. The DNS may yield multiple addresses, in which case insert the
3593 extra ones into the list.
3594
3595 . Get the retry data if not previously obtained for this address and set the
3596 field which remembers the state of this address. Skip if the retry time is
3597 not reached. If not, remember whether retry data was found. The retry string
3598 contains both the name and the IP address.
3599
3600 . Scan the list of addresses and mark those whose status is DEFER as
3601 PENDING_DEFER. These are the only ones that will be processed in this cycle
3602 of the hosts loop.
3603
3604 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
3605 Some addresses may be successfully delivered, others may fail, and yet
3606 others may get temporary errors and so get marked DEFER.
3607
3608 . The return from the delivery attempt is OK if a connection was made and a
3609 valid SMTP dialogue was completed. Otherwise it is DEFER.
3610
3611 . If OK, add a "remove" retry item for this host/IPaddress, if any.
3612
3613 . If fail to connect, or other defer state, add a retry item.
3614
3615 . If there are any addresses whose status is still DEFER, carry on to the
3616 next host/IPaddress, unless we have tried the number of hosts given
3617 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
3618 there is some fancy logic for hosts_max_try that means its limit can be
3619 overstepped in some circumstances.
3620
3621 If we get to the end of the list, all hosts have deferred at least one address,
3622 or not reached their retry times. If delay_after_cutoff is unset, it requests a
3623 delivery attempt to those hosts whose last try was before the arrival time of
3624 the current message. To cope with this, we have to go round the loop a second
3625 time. After that, set the status and error data for any addresses that haven't
3626 had it set already. */
3627
3628 for (cutoff_retry = 0;
3629 expired && cutoff_retry < (ob->delay_after_cutoff ? 1 : 2);
3630 cutoff_retry++)
3631 {
3632 host_item *nexthost = NULL;
3633 int unexpired_hosts_tried = 0;
3634
3635 for (host = hostlist;
3636 host
3637 && unexpired_hosts_tried < ob->hosts_max_try
3638 && total_hosts_tried < ob->hosts_max_try_hardlimit;
3639 host = nexthost)
3640 {
3641 int rc;
3642 int host_af;
3643 uschar *rs;
3644 BOOL host_is_expired = FALSE;
3645 BOOL message_defer = FALSE;
3646 BOOL some_deferred = FALSE;
3647 address_item *first_addr = NULL;
3648 uschar *interface = NULL;
3649 uschar *retry_host_key = NULL;
3650 uschar *retry_message_key = NULL;
3651 uschar *serialize_key = NULL;
3652
3653 /* Default next host is next host. :-) But this can vary if the
3654 hosts_max_try limit is hit (see below). It may also be reset if a host
3655 address is looked up here (in case the host was multihomed). */
3656
3657 nexthost = host->next;
3658
3659 /* If the address hasn't yet been obtained from the host name, look it up
3660 now, unless the host is already marked as unusable. If it is marked as
3661 unusable, it means that the router was unable to find its IP address (in
3662 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
3663 the lookup failed last time. We don't get this far if *all* MX records
3664 point to non-existent hosts; that is treated as a hard error.
3665
3666 We can just skip this host entirely. When the hosts came from the router,
3667 the address will timeout based on the other host(s); when the address is
3668 looked up below, there is an explicit retry record added.
3669
3670 Note that we mustn't skip unusable hosts if the address is not unset; they
3671 may be needed as expired hosts on the 2nd time round the cutoff loop. */
3672
3673 if (!host->address)
3674 {
3675 int new_port, flags;
3676 host_item *hh;
3677
3678 if (host->status >= hstatus_unusable)
3679 {
3680 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
3681 host->name);
3682 continue;
3683 }
3684
3685 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
3686
3687 /* The host name is permitted to have an attached port. Find it, and
3688 strip it from the name. Just remember it for now. */
3689
3690 new_port = host_item_get_port(host);
3691
3692 /* Count hosts looked up */
3693
3694 hosts_looked_up++;
3695
3696 /* Find by name if so configured, or if it's an IP address. We don't
3697 just copy the IP address, because we need the test-for-local to happen. */
3698
3699 flags = HOST_FIND_BY_A;
3700 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
3701 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
3702
3703 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
3704 rc = host_find_byname(host, NULL, flags, NULL, TRUE);
3705 else
3706 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
3707 &ob->dnssec, /* domains for request/require */
3708 NULL, NULL);
3709
3710 /* Update the host (and any additional blocks, resulting from
3711 multihoming) with a host-specific port, if any. */
3712
3713 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
3714
3715 /* Failure to find the host at this time (usually DNS temporary failure)
3716 is really a kind of routing failure rather than a transport failure.
3717 Therefore we add a retry item of the routing kind, not to stop us trying
3718 to look this name up here again, but to ensure the address gets timed
3719 out if the failures go on long enough. A complete failure at this point
3720 commonly points to a configuration error, but the best action is still
3721 to carry on for the next host. */
3722
3723 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_SECURITY || rc == HOST_FIND_FAILED)
3724 {
3725 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
3726 expired = FALSE;
3727 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
3728 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
3729 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
3730 host->status = hstatus_unusable;
3731
3732 for (addr = addrlist; addr; addr = addr->next)
3733 {
3734 if (addr->transport_return != DEFER) continue;
3735 addr->basic_errno = ERRNO_UNKNOWNHOST;
3736 addr->message = string_sprintf(
3737 rc == HOST_FIND_SECURITY
3738 ? "lookup of IP address for %s was insecure"
3739 : "failed to lookup IP address for %s",
3740 host->name);
3741 }
3742 continue;
3743 }
3744
3745 /* If the host is actually the local host, we may have a problem, or
3746 there may be some cunning configuration going on. In the problem case,
3747 log things and give up. The default transport status is already DEFER. */
3748
3749 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
3750 {
3751 for (addr = addrlist; addr; addr = addr->next)
3752 {
3753 addr->basic_errno = 0;
3754 addr->message = string_sprintf("%s transport found host %s to be "
3755 "local", tblock->name, host->name);
3756 }
3757 goto END_TRANSPORT;
3758 }
3759 } /* End of block for IP address lookup */
3760
3761 /* If this is a continued delivery, we are interested only in the host
3762 which matches the name of the existing open channel. The check is put
3763 here after the local host lookup, in case the name gets expanded as a
3764 result of the lookup. Set expired FALSE, to save the outer loop executing
3765 twice. */
3766
3767 if ( continue_hostname
3768 && ( Ustrcmp(continue_hostname, host->name) != 0
3769 || Ustrcmp(continue_host_address, host->address) != 0
3770 ) )
3771 {
3772 expired = FALSE;
3773 continue; /* With next host */
3774 }
3775
3776 /* Reset the default next host in case a multihomed host whose addresses
3777 are not looked up till just above added to the host list. */
3778
3779 nexthost = host->next;
3780
3781 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
3782 domain is in queue_smtp_domains, we don't actually want to attempt any
3783 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
3784 there is a lookup defer in queue_smtp_domains, proceed as if the domain
3785 were not in it. We don't want to hold up all SMTP deliveries! Except when
3786 doing a two-stage queue run, don't do this if forcing. */
3787
3788 if ((!deliver_force || queue_2stage) && (queue_smtp ||
3789 match_isinlist(addrlist->domain,
3790 (const uschar **)&queue_smtp_domains, 0,
3791 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
3792 {
3793 expired = FALSE;
3794 for (addr = addrlist; addr; addr = addr->next)
3795 if (addr->transport_return == DEFER)
3796 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
3797 continue; /* With next host */
3798 }
3799
3800 /* Count hosts being considered - purely for an intelligent comment
3801 if none are usable. */
3802
3803 hosts_total++;
3804
3805 /* Set $host and $host address now in case they are needed for the
3806 interface expansion or the serialize_hosts check; they remain set if an
3807 actual delivery happens. */
3808
3809 deliver_host = host->name;
3810 deliver_host_address = host->address;
3811 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
3812 : host->dnssec == DS_NO ? US"no"
3813 : US"";
3814
3815 /* Set up a string for adding to the retry key if the port number is not
3816 the standard SMTP port. A host may have its own port setting that overrides
3817 the default. */
3818
3819 pistring = string_sprintf(":%d", host->port == PORT_NONE
3820 ? port : host->port);
3821 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
3822
3823 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
3824 string is set, even if constant (