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Drain socket to get clean TCP FINs
[exim.git] / src / src / transports / smtp.c
1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
4
5 /* Copyright (c) University of Cambridge 1995 - 2016 */
6 /* See the file NOTICE for conditions of use and distribution. */
7
8 #include "../exim.h"
9 #include "smtp.h"
10
11 #define PENDING 256
12 #define PENDING_DEFER (PENDING + DEFER)
13 #define PENDING_OK (PENDING + OK)
14
15 #define DELIVER_BUFFER_SIZE 4096
16
17
18 /* Options specific to the smtp transport. This transport also supports LMTP
19 over TCP/IP. The options must be in alphabetic order (note that "_" comes
20 before the lower case letters). Some live in the transport_instance block so as
21 to be publicly visible; these are flagged with opt_public. */
22
23 optionlist smtp_transport_options[] = {
24 { "*expand_multi_domain", opt_stringptr | opt_hidden | opt_public,
25 (void *)offsetof(transport_instance, expand_multi_domain) },
26 { "*expand_retry_include_ip_address", opt_stringptr | opt_hidden,
27 (void *)(offsetof(smtp_transport_options_block, expand_retry_include_ip_address)) },
28
29 { "address_retry_include_sender", opt_bool,
30 (void *)offsetof(smtp_transport_options_block, address_retry_include_sender) },
31 { "allow_localhost", opt_bool,
32 (void *)offsetof(smtp_transport_options_block, allow_localhost) },
33 { "authenticated_sender", opt_stringptr,
34 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
35 { "authenticated_sender_force", opt_bool,
36 (void *)offsetof(smtp_transport_options_block, authenticated_sender_force) },
37 { "command_timeout", opt_time,
38 (void *)offsetof(smtp_transport_options_block, command_timeout) },
39 { "connect_timeout", opt_time,
40 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
41 { "connection_max_messages", opt_int | opt_public,
42 (void *)offsetof(transport_instance, connection_max_messages) },
43 { "data_timeout", opt_time,
44 (void *)offsetof(smtp_transport_options_block, data_timeout) },
45 { "delay_after_cutoff", opt_bool,
46 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
47 #ifndef DISABLE_DKIM
48 { "dkim_canon", opt_stringptr,
49 (void *)offsetof(smtp_transport_options_block, dkim.dkim_canon) },
50 { "dkim_domain", opt_stringptr,
51 (void *)offsetof(smtp_transport_options_block, dkim.dkim_domain) },
52 { "dkim_private_key", opt_stringptr,
53 (void *)offsetof(smtp_transport_options_block, dkim.dkim_private_key) },
54 { "dkim_selector", opt_stringptr,
55 (void *)offsetof(smtp_transport_options_block, dkim.dkim_selector) },
56 { "dkim_sign_headers", opt_stringptr,
57 (void *)offsetof(smtp_transport_options_block, dkim.dkim_sign_headers) },
58 { "dkim_strict", opt_stringptr,
59 (void *)offsetof(smtp_transport_options_block, dkim.dkim_strict) },
60 #endif
61 { "dns_qualify_single", opt_bool,
62 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
63 { "dns_search_parents", opt_bool,
64 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
65 { "dnssec_request_domains", opt_stringptr,
66 (void *)offsetof(smtp_transport_options_block, dnssec.request) },
67 { "dnssec_require_domains", opt_stringptr,
68 (void *)offsetof(smtp_transport_options_block, dnssec.require) },
69 { "dscp", opt_stringptr,
70 (void *)offsetof(smtp_transport_options_block, dscp) },
71 { "fallback_hosts", opt_stringptr,
72 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
73 { "final_timeout", opt_time,
74 (void *)offsetof(smtp_transport_options_block, final_timeout) },
75 { "gethostbyname", opt_bool,
76 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
77 { "helo_data", opt_stringptr,
78 (void *)offsetof(smtp_transport_options_block, helo_data) },
79 { "hosts", opt_stringptr,
80 (void *)offsetof(smtp_transport_options_block, hosts) },
81 { "hosts_avoid_esmtp", opt_stringptr,
82 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
83 { "hosts_avoid_pipelining", opt_stringptr,
84 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
85 #ifdef SUPPORT_TLS
86 { "hosts_avoid_tls", opt_stringptr,
87 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
88 #endif
89 { "hosts_max_try", opt_int,
90 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
91 { "hosts_max_try_hardlimit", opt_int,
92 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
93 #ifdef SUPPORT_TLS
94 { "hosts_nopass_tls", opt_stringptr,
95 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
96 #endif
97 { "hosts_override", opt_bool,
98 (void *)offsetof(smtp_transport_options_block, hosts_override) },
99 { "hosts_randomize", opt_bool,
100 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
101 #if defined(SUPPORT_TLS) && !defined(DISABLE_OCSP)
102 { "hosts_request_ocsp", opt_stringptr,
103 (void *)offsetof(smtp_transport_options_block, hosts_request_ocsp) },
104 #endif
105 { "hosts_require_auth", opt_stringptr,
106 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
107 #ifdef SUPPORT_TLS
108 # ifdef EXPERIMENTAL_DANE
109 { "hosts_require_dane", opt_stringptr,
110 (void *)offsetof(smtp_transport_options_block, hosts_require_dane) },
111 # endif
112 # ifndef DISABLE_OCSP
113 { "hosts_require_ocsp", opt_stringptr,
114 (void *)offsetof(smtp_transport_options_block, hosts_require_ocsp) },
115 # endif
116 { "hosts_require_tls", opt_stringptr,
117 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
118 #endif
119 { "hosts_try_auth", opt_stringptr,
120 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
121 { "hosts_try_chunking", opt_stringptr,
122 (void *)offsetof(smtp_transport_options_block, hosts_try_chunking) },
123 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
124 { "hosts_try_dane", opt_stringptr,
125 (void *)offsetof(smtp_transport_options_block, hosts_try_dane) },
126 #endif
127 #ifndef DISABLE_PRDR
128 { "hosts_try_prdr", opt_stringptr,
129 (void *)offsetof(smtp_transport_options_block, hosts_try_prdr) },
130 #endif
131 #ifdef SUPPORT_TLS
132 { "hosts_verify_avoid_tls", opt_stringptr,
133 (void *)offsetof(smtp_transport_options_block, hosts_verify_avoid_tls) },
134 #endif
135 { "interface", opt_stringptr,
136 (void *)offsetof(smtp_transport_options_block, interface) },
137 { "keepalive", opt_bool,
138 (void *)offsetof(smtp_transport_options_block, keepalive) },
139 { "lmtp_ignore_quota", opt_bool,
140 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
141 { "max_rcpt", opt_int | opt_public,
142 (void *)offsetof(transport_instance, max_addresses) },
143 { "multi_domain", opt_expand_bool | opt_public,
144 (void *)offsetof(transport_instance, multi_domain) },
145 { "port", opt_stringptr,
146 (void *)offsetof(smtp_transport_options_block, port) },
147 { "protocol", opt_stringptr,
148 (void *)offsetof(smtp_transport_options_block, protocol) },
149 { "retry_include_ip_address", opt_expand_bool,
150 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
151 { "serialize_hosts", opt_stringptr,
152 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
153 { "size_addition", opt_int,
154 (void *)offsetof(smtp_transport_options_block, size_addition) }
155 #ifdef SUPPORT_SOCKS
156 ,{ "socks_proxy", opt_stringptr,
157 (void *)offsetof(smtp_transport_options_block, socks_proxy) }
158 #endif
159 #ifdef SUPPORT_TLS
160 ,{ "tls_certificate", opt_stringptr,
161 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
162 { "tls_crl", opt_stringptr,
163 (void *)offsetof(smtp_transport_options_block, tls_crl) },
164 { "tls_dh_min_bits", opt_int,
165 (void *)offsetof(smtp_transport_options_block, tls_dh_min_bits) },
166 { "tls_privatekey", opt_stringptr,
167 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
168 { "tls_require_ciphers", opt_stringptr,
169 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
170 { "tls_sni", opt_stringptr,
171 (void *)offsetof(smtp_transport_options_block, tls_sni) },
172 { "tls_tempfail_tryclear", opt_bool,
173 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
174 { "tls_try_verify_hosts", opt_stringptr,
175 (void *)offsetof(smtp_transport_options_block, tls_try_verify_hosts) },
176 { "tls_verify_cert_hostnames", opt_stringptr,
177 (void *)offsetof(smtp_transport_options_block,tls_verify_cert_hostnames)},
178 { "tls_verify_certificates", opt_stringptr,
179 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) },
180 { "tls_verify_hosts", opt_stringptr,
181 (void *)offsetof(smtp_transport_options_block, tls_verify_hosts) }
182 #endif
183 };
184
185 /* Size of the options list. An extern variable has to be used so that its
186 address can appear in the tables drtables.c. */
187
188 int smtp_transport_options_count =
189 sizeof(smtp_transport_options)/sizeof(optionlist);
190
191 /* Default private options block for the smtp transport. */
192
193 smtp_transport_options_block smtp_transport_option_defaults = {
194 NULL, /* hosts */
195 NULL, /* fallback_hosts */
196 NULL, /* hostlist */
197 NULL, /* fallback_hostlist */
198 NULL, /* authenticated_sender */
199 US"$primary_hostname", /* helo_data */
200 NULL, /* interface */
201 NULL, /* port */
202 US"smtp", /* protocol */
203 NULL, /* DSCP */
204 NULL, /* serialize_hosts */
205 NULL, /* hosts_try_auth */
206 NULL, /* hosts_require_auth */
207 US"*", /* hosts_try_chunking */
208 #ifdef EXPERIMENTAL_DANE
209 NULL, /* hosts_try_dane */
210 NULL, /* hosts_require_dane */
211 #endif
212 #ifndef DISABLE_PRDR
213 US"*", /* hosts_try_prdr */
214 #endif
215 #ifndef DISABLE_OCSP
216 US"*", /* hosts_request_ocsp (except under DANE; tls_client_start()) */
217 NULL, /* hosts_require_ocsp */
218 #endif
219 NULL, /* hosts_require_tls */
220 NULL, /* hosts_avoid_tls */
221 NULL, /* hosts_verify_avoid_tls */
222 NULL, /* hosts_avoid_pipelining */
223 NULL, /* hosts_avoid_esmtp */
224 NULL, /* hosts_nopass_tls */
225 5*60, /* command_timeout */
226 5*60, /* connect_timeout; shorter system default overrides */
227 5*60, /* data timeout */
228 10*60, /* final timeout */
229 1024, /* size_addition */
230 5, /* hosts_max_try */
231 50, /* hosts_max_try_hardlimit */
232 TRUE, /* address_retry_include_sender */
233 FALSE, /* allow_localhost */
234 FALSE, /* authenticated_sender_force */
235 FALSE, /* gethostbyname */
236 TRUE, /* dns_qualify_single */
237 FALSE, /* dns_search_parents */
238 { NULL, NULL }, /* dnssec_domains {request,require} */
239 TRUE, /* delay_after_cutoff */
240 FALSE, /* hosts_override */
241 FALSE, /* hosts_randomize */
242 TRUE, /* keepalive */
243 FALSE, /* lmtp_ignore_quota */
244 NULL, /* expand_retry_include_ip_address */
245 TRUE /* retry_include_ip_address */
246 #ifdef SUPPORT_SOCKS
247 ,NULL /* socks_proxy */
248 #endif
249 #ifdef SUPPORT_TLS
250 ,NULL, /* tls_certificate */
251 NULL, /* tls_crl */
252 NULL, /* tls_privatekey */
253 NULL, /* tls_require_ciphers */
254 NULL, /* tls_sni */
255 US"system", /* tls_verify_certificates */
256 EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
257 /* tls_dh_min_bits */
258 TRUE, /* tls_tempfail_tryclear */
259 NULL, /* tls_verify_hosts */
260 US"*", /* tls_try_verify_hosts */
261 US"*" /* tls_verify_cert_hostnames */
262 #endif
263 #ifndef DISABLE_DKIM
264 , {NULL, /* dkim_canon */
265 NULL, /* dkim_domain */
266 NULL, /* dkim_private_key */
267 NULL, /* dkim_selector */
268 NULL, /* dkim_sign_headers */
269 NULL, /* dkim_strict */
270 FALSE} /* dot_stuffed */
271 #endif
272 };
273
274 /* some DSN flags for use later */
275
276 static int rf_list[] = {rf_notify_never, rf_notify_success,
277 rf_notify_failure, rf_notify_delay };
278
279 static uschar *rf_names[] = { US"NEVER", US"SUCCESS", US"FAILURE", US"DELAY" };
280
281
282
283 /* Local statics */
284
285 static uschar *smtp_command; /* Points to last cmd for error messages */
286 static uschar *mail_command; /* Points to MAIL cmd for error messages */
287 static BOOL update_waiting; /* TRUE to update the "wait" database */
288 static BOOL pipelining_active; /* current transaction is in pipe mode */
289
290
291 /*************************************************
292 * Setup entry point *
293 *************************************************/
294
295 /* This function is called when the transport is about to be used,
296 but before running it in a sub-process. It is used for two things:
297
298 (1) To set the fallback host list in addresses, when delivering.
299 (2) To pass back the interface, port, protocol, and other options, for use
300 during callout verification.
301
302 Arguments:
303 tblock pointer to the transport instance block
304 addrlist list of addresses about to be transported
305 tf if not NULL, pointer to block in which to return options
306 uid the uid that will be set (not used)
307 gid the gid that will be set (not used)
308 errmsg place for error message (not used)
309
310 Returns: OK always (FAIL, DEFER not used)
311 */
312
313 static int
314 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
315 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
316 {
317 smtp_transport_options_block *ob =
318 (smtp_transport_options_block *)(tblock->options_block);
319
320 errmsg = errmsg; /* Keep picky compilers happy */
321 uid = uid;
322 gid = gid;
323
324 /* Pass back options if required. This interface is getting very messy. */
325
326 if (tf != NULL)
327 {
328 tf->interface = ob->interface;
329 tf->port = ob->port;
330 tf->protocol = ob->protocol;
331 tf->hosts = ob->hosts;
332 tf->hosts_override = ob->hosts_override;
333 tf->hosts_randomize = ob->hosts_randomize;
334 tf->gethostbyname = ob->gethostbyname;
335 tf->qualify_single = ob->dns_qualify_single;
336 tf->search_parents = ob->dns_search_parents;
337 tf->helo_data = ob->helo_data;
338 }
339
340 /* Set the fallback host list for all the addresses that don't have fallback
341 host lists, provided that the local host wasn't present in the original host
342 list. */
343
344 if (!testflag(addrlist, af_local_host_removed))
345 {
346 for (; addrlist != NULL; addrlist = addrlist->next)
347 if (addrlist->fallback_hosts == NULL)
348 addrlist->fallback_hosts = ob->fallback_hostlist;
349 }
350
351 return OK;
352 }
353
354
355
356 /*************************************************
357 * Initialization entry point *
358 *************************************************/
359
360 /* Called for each instance, after its options have been read, to
361 enable consistency checks to be done, or anything else that needs
362 to be set up.
363
364 Argument: pointer to the transport instance block
365 Returns: nothing
366 */
367
368 void
369 smtp_transport_init(transport_instance *tblock)
370 {
371 smtp_transport_options_block *ob =
372 (smtp_transport_options_block *)(tblock->options_block);
373
374 /* Retry_use_local_part defaults FALSE if unset */
375
376 if (tblock->retry_use_local_part == TRUE_UNSET)
377 tblock->retry_use_local_part = FALSE;
378
379 /* Set the default port according to the protocol */
380
381 if (ob->port == NULL)
382 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
383 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
384
385 /* Set up the setup entry point, to be called before subprocesses for this
386 transport. */
387
388 tblock->setup = smtp_transport_setup;
389
390 /* Complain if any of the timeouts are zero. */
391
392 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
393 ob->final_timeout <= 0)
394 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
395 "command, data, or final timeout value is zero for %s transport",
396 tblock->name);
397
398 /* If hosts_override is set and there are local hosts, set the global
399 flag that stops verify from showing router hosts. */
400
401 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
402
403 /* If there are any fallback hosts listed, build a chain of host items
404 for them, but do not do any lookups at this time. */
405
406 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
407 }
408
409
410
411
412
413 /*************************************************
414 * Set delivery info into all active addresses *
415 *************************************************/
416
417 /* Only addresses whose status is >= PENDING are relevant. A lesser
418 status means that an address is not currently being processed.
419
420 Arguments:
421 addrlist points to a chain of addresses
422 errno_value to put in each address's errno field
423 msg to put in each address's message field
424 rc to put in each address's transport_return field
425 pass_message if TRUE, set the "pass message" flag in the address
426 host if set, mark addrs as having used this host
427 smtp_greeting from peer
428 helo_response from peer
429
430 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
431 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
432 this particular type of timeout.
433
434 Returns: nothing
435 */
436
437 static void
438 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
439 BOOL pass_message, host_item * host
440 #ifdef EXPERIMENTAL_DSN_INFO
441 , const uschar * smtp_greeting, const uschar * helo_response
442 #endif
443 )
444 {
445 address_item *addr;
446 int orvalue = 0;
447 if (errno_value == ERRNO_CONNECTTIMEOUT)
448 {
449 errno_value = ETIMEDOUT;
450 orvalue = RTEF_CTOUT;
451 }
452 for (addr = addrlist; addr; addr = addr->next)
453 if (addr->transport_return >= PENDING)
454 {
455 addr->basic_errno = errno_value;
456 addr->more_errno |= orvalue;
457 if (msg != NULL)
458 {
459 addr->message = msg;
460 if (pass_message) setflag(addr, af_pass_message);
461 }
462 addr->transport_return = rc;
463 if (host)
464 {
465 addr->host_used = host;
466 #ifdef EXPERIMENTAL_DSN_INFO
467 if (smtp_greeting)
468 {uschar * s = Ustrchr(smtp_greeting, '\n'); if (s) *s = '\0';}
469 addr->smtp_greeting = smtp_greeting;
470
471 if (helo_response)
472 {uschar * s = Ustrchr(helo_response, '\n'); if (s) *s = '\0';}
473 addr->helo_response = helo_response;
474 #endif
475 }
476 }
477 }
478
479 static void
480 set_errno_nohost(address_item *addrlist, int errno_value, uschar *msg, int rc,
481 BOOL pass_message)
482 {
483 set_errno(addrlist, errno_value, msg, rc, pass_message, NULL
484 #ifdef EXPERIMENTAL_DSN_INFO
485 , NULL, NULL
486 #endif
487 );
488 }
489
490
491 /*************************************************
492 * Check an SMTP response *
493 *************************************************/
494
495 /* This function is given an errno code and the SMTP response buffer
496 to analyse, together with the host identification for generating messages. It
497 sets an appropriate message and puts the first digit of the response code into
498 the yield variable. If no response was actually read, a suitable digit is
499 chosen.
500
501 Arguments:
502 host the current host, to get its name for messages
503 errno_value pointer to the errno value
504 more_errno from the top address for use with ERRNO_FILTER_FAIL
505 buffer the SMTP response buffer
506 yield where to put a one-digit SMTP response code
507 message where to put an errror message
508 pass_message set TRUE if message is an SMTP response
509
510 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
511 */
512
513 static BOOL
514 check_response(host_item *host, int *errno_value, int more_errno,
515 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
516 {
517 uschar * pl = pipelining_active ? US"pipelined " : US"";
518
519 *yield = '4'; /* Default setting is to give a temporary error */
520
521 /* Handle response timeout */
522
523 if (*errno_value == ETIMEDOUT)
524 {
525 *message = US string_sprintf("SMTP timeout after %s%s",
526 pl, smtp_command);
527 if (transport_count > 0)
528 *message = US string_sprintf("%s (%d bytes written)", *message,
529 transport_count);
530 return FALSE;
531 }
532
533 /* Handle malformed SMTP response */
534
535 if (*errno_value == ERRNO_SMTPFORMAT)
536 {
537 const uschar *malfresp = string_printing(buffer);
538 while (isspace(*malfresp)) malfresp++;
539 *message = *malfresp == 0
540 ? string_sprintf("Malformed SMTP reply (an empty line) "
541 "in response to %s%s", pl, smtp_command)
542 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
543 pl, smtp_command, malfresp);
544 return FALSE;
545 }
546
547 /* Handle a failed filter process error; can't send QUIT as we mustn't
548 end the DATA. */
549
550 if (*errno_value == ERRNO_FILTER_FAIL)
551 {
552 *message = US string_sprintf("transport filter process failed (%d)%s",
553 more_errno,
554 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
555 return FALSE;
556 }
557
558 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
559 end the DATA. */
560
561 if (*errno_value == ERRNO_CHHEADER_FAIL)
562 {
563 *message =
564 US string_sprintf("failed to expand headers_add or headers_remove: %s",
565 expand_string_message);
566 return FALSE;
567 }
568
569 /* Handle failure to write a complete data block */
570
571 if (*errno_value == ERRNO_WRITEINCOMPLETE)
572 {
573 *message = US string_sprintf("failed to write a data block");
574 return FALSE;
575 }
576
577 #ifdef SUPPORT_I18N
578 /* Handle lack of advertised SMTPUTF8, for international message */
579 if (*errno_value == ERRNO_UTF8_FWD)
580 {
581 *message = US string_sprintf("utf8 support required but not offered for forwarding");
582 DEBUG(D_deliver|D_transport) debug_printf("%s\n", *message);
583 return TRUE;
584 }
585 #endif
586
587 /* Handle error responses from the remote mailer. */
588
589 if (buffer[0] != 0)
590 {
591 const uschar *s = string_printing(buffer);
592 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
593 "%s", pl, smtp_command, s);
594 *pass_message = TRUE;
595 *yield = buffer[0];
596 return TRUE;
597 }
598
599 /* No data was read. If there is no errno, this must be the EOF (i.e.
600 connection closed) case, which causes deferral. An explicit connection reset
601 error has the same effect. Otherwise, put the host's identity in the message,
602 leaving the errno value to be interpreted as well. In all cases, we have to
603 assume the connection is now dead. */
604
605 if (*errno_value == 0 || *errno_value == ECONNRESET)
606 {
607 *errno_value = ERRNO_SMTPCLOSED;
608 *message = US string_sprintf("Remote host closed connection "
609 "in response to %s%s", pl, smtp_command);
610 }
611 else *message = US string_sprintf("%s [%s]", host->name, host->address);
612
613 return FALSE;
614 }
615
616
617
618 /*************************************************
619 * Write error message to logs *
620 *************************************************/
621
622 /* This writes to the main log and to the message log.
623
624 Arguments:
625 addr the address item containing error information
626 host the current host
627
628 Returns: nothing
629 */
630
631 static void
632 write_logs(address_item *addr, host_item *host)
633 {
634 uschar * message = LOGGING(outgoing_port)
635 ? string_sprintf("H=%s [%s]:%d", host->name, host->address,
636 host->port == PORT_NONE ? 25 : host->port)
637 : string_sprintf("H=%s [%s]", host->name, host->address);
638
639 if (addr->message)
640 {
641 message = string_sprintf("%s: %s", message, addr->message);
642 if (addr->basic_errno > 0)
643 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
644 log_write(0, LOG_MAIN, "%s", message);
645 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
646 }
647 else
648 {
649 const uschar * s = exim_errstr(addr->basic_errno);
650 log_write(0, LOG_MAIN, "%s %s", message, s);
651 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), message, s);
652 }
653 }
654
655 static void
656 msglog_line(host_item * host, uschar * message)
657 {
658 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
659 host->name, host->address, message);
660 }
661
662
663
664 #ifndef DISABLE_EVENT
665 /*************************************************
666 * Post-defer action *
667 *************************************************/
668
669 /* This expands an arbitrary per-transport string.
670 It might, for example, be used to write to the database log.
671
672 Arguments:
673 addr the address item containing error information
674 host the current host
675
676 Returns: nothing
677 */
678
679 static void
680 deferred_event_raise(address_item *addr, host_item *host)
681 {
682 uschar * action = addr->transport->event_action;
683 const uschar * save_domain;
684 uschar * save_local;
685
686 if (!action)
687 return;
688
689 save_domain = deliver_domain;
690 save_local = deliver_localpart;
691
692 /*XXX would ip & port already be set up? */
693 deliver_host_address = string_copy(host->address);
694 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
695 event_defer_errno = addr->basic_errno;
696
697 router_name = addr->router->name;
698 transport_name = addr->transport->name;
699 deliver_domain = addr->domain;
700 deliver_localpart = addr->local_part;
701
702 (void) event_raise(action, US"msg:host:defer",
703 addr->message
704 ? addr->basic_errno > 0
705 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
706 : string_copy(addr->message)
707 : addr->basic_errno > 0
708 ? string_copy(US strerror(addr->basic_errno))
709 : NULL);
710
711 deliver_localpart = save_local;
712 deliver_domain = save_domain;
713 router_name = transport_name = NULL;
714 }
715 #endif
716
717 /*************************************************
718 * Synchronize SMTP responses *
719 *************************************************/
720
721 /* This function is called from smtp_deliver() to receive SMTP responses from
722 the server, and match them up with the commands to which they relate. When
723 PIPELINING is not in use, this function is called after every command, and is
724 therefore somewhat over-engineered, but it is simpler to use a single scheme
725 that works both with and without PIPELINING instead of having two separate sets
726 of code.
727
728 The set of commands that are buffered up with pipelining may start with MAIL
729 and may end with DATA; in between are RCPT commands that correspond to the
730 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
731 etc.) are never buffered.
732
733 Errors after MAIL or DATA abort the whole process leaving the response in the
734 buffer. After MAIL, pending responses are flushed, and the original command is
735 re-instated in big_buffer for error messages. For RCPT commands, the remote is
736 permitted to reject some recipient addresses while accepting others. However
737 certain errors clearly abort the whole process. Set the value in
738 transport_return to PENDING_OK if the address is accepted. If there is a
739 subsequent general error, it will get reset accordingly. If not, it will get
740 converted to OK at the end.
741
742 Arguments:
743 addrlist the complete address list
744 include_affixes TRUE if affixes include in RCPT
745 sync_addr ptr to the ptr of the one to start scanning at (updated)
746 host the host we are connected to
747 count the number of responses to read
748 address_retry_
749 include_sender true if 4xx retry is to include the sender it its key
750 pending_MAIL true if the first response is for MAIL
751 pending_DATA 0 if last command sent was not DATA
752 +1 if previously had a good recipient
753 -1 if not previously had a good recipient
754 inblock incoming SMTP block
755 timeout timeout value
756 buffer buffer for reading response
757 buffsize size of buffer
758
759 Returns: 3 if at least one address had 2xx and one had 5xx
760 2 if at least one address had 5xx but none had 2xx
761 1 if at least one host had a 2xx response, but none had 5xx
762 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
763 -1 timeout while reading RCPT response
764 -2 I/O or other non-response error for RCPT
765 -3 DATA or MAIL failed - errno and buffer set
766 */
767
768 static int
769 sync_responses(address_item *addrlist, BOOL include_affixes,
770 address_item **sync_addr, host_item *host, int count,
771 BOOL address_retry_include_sender, BOOL pending_MAIL,
772 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
773 int buffsize)
774 {
775 address_item *addr = *sync_addr;
776 int yield = 0;
777
778 /* Handle the response for a MAIL command. On error, reinstate the original
779 command in big_buffer for error message use, and flush any further pending
780 responses before returning, except after I/O errors and timeouts. */
781
782 if (pending_MAIL)
783 {
784 count--;
785 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
786 {
787 DEBUG(D_transport) debug_printf("bad response for MAIL\n");
788 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
789 if (errno == 0 && buffer[0] != 0)
790 {
791 uschar flushbuffer[4096];
792 int save_errno = 0;
793 if (buffer[0] == '4')
794 {
795 save_errno = ERRNO_MAIL4XX;
796 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
797 }
798 while (count-- > 0)
799 {
800 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
801 '2', timeout)
802 && (errno != 0 || flushbuffer[0] == 0))
803 break;
804 }
805 errno = save_errno;
806 }
807
808 if (pending_DATA) count--; /* Number of RCPT responses to come */
809 while (count-- > 0) /* Mark any pending addrs with the host used */
810 {
811 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
812 addr->host_used = host;
813 addr = addr->next;
814 }
815 return -3;
816 }
817 }
818
819 if (pending_DATA) count--; /* Number of RCPT responses to come */
820
821 /* Read and handle the required number of RCPT responses, matching each one up
822 with an address by scanning for the next address whose status is PENDING_DEFER.
823 */
824
825 while (count-- > 0)
826 {
827 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
828
829 /* The address was accepted */
830 addr->host_used = host;
831
832 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
833 {
834 yield |= 1;
835 addr->transport_return = PENDING_OK;
836
837 /* If af_dr_retry_exists is set, there was a routing delay on this address;
838 ensure that any address-specific retry record is expunged. We do this both
839 for the basic key and for the version that also includes the sender. */
840
841 if (testflag(addr, af_dr_retry_exists))
842 {
843 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
844 sender_address);
845 retry_add_item(addr, altkey, rf_delete);
846 retry_add_item(addr, addr->address_retry_key, rf_delete);
847 }
848 }
849
850 /* Timeout while reading the response */
851
852 else if (errno == ETIMEDOUT)
853 {
854 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
855 transport_rcpt_address(addr, include_affixes));
856 set_errno_nohost(addrlist, ETIMEDOUT, message, DEFER, FALSE);
857 retry_add_item(addr, addr->address_retry_key, 0);
858 update_waiting = FALSE;
859 return -1;
860 }
861
862 /* Handle other errors in obtaining an SMTP response by returning -1. This
863 will cause all the addresses to be deferred. Restore the SMTP command in
864 big_buffer for which we are checking the response, so the error message
865 makes sense. */
866
867 else if (errno != 0 || buffer[0] == 0)
868 {
869 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
870 transport_rcpt_address(addr, include_affixes));
871 return -2;
872 }
873
874 /* Handle SMTP permanent and temporary response codes. */
875
876 else
877 {
878 addr->message =
879 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
880 "%s", transport_rcpt_address(addr, include_affixes),
881 string_printing(buffer));
882 setflag(addr, af_pass_message);
883 msglog_line(host, addr->message);
884
885 /* The response was 5xx */
886
887 if (buffer[0] == '5')
888 {
889 addr->transport_return = FAIL;
890 yield |= 2;
891 }
892
893 /* The response was 4xx */
894
895 else
896 {
897 addr->transport_return = DEFER;
898 addr->basic_errno = ERRNO_RCPT4XX;
899 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
900
901 #ifndef DISABLE_EVENT
902 event_defer_errno = addr->more_errno;
903 msg_event_raise(US"msg:rcpt:host:defer", addr);
904 #endif
905
906 /* Log temporary errors if there are more hosts to be tried.
907 If not, log this last one in the == line. */
908
909 if (host->next)
910 log_write(0, LOG_MAIN, "H=%s [%s]: %s", host->name, host->address, addr->message);
911
912 #ifndef DISABLE_EVENT
913 else
914 msg_event_raise(US"msg:rcpt:defer", addr);
915 #endif
916
917 /* Do not put this message on the list of those waiting for specific
918 hosts, as otherwise it is likely to be tried too often. */
919
920 update_waiting = FALSE;
921
922 /* Add a retry item for the address so that it doesn't get tried again
923 too soon. If address_retry_include_sender is true, add the sender address
924 to the retry key. */
925
926 if (address_retry_include_sender)
927 {
928 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
929 sender_address);
930 retry_add_item(addr, altkey, 0);
931 }
932 else retry_add_item(addr, addr->address_retry_key, 0);
933 }
934 }
935 } /* Loop for next RCPT response */
936
937 /* Update where to start at for the next block of responses, unless we
938 have already handled all the addresses. */
939
940 if (addr != NULL) *sync_addr = addr->next;
941
942 /* Handle a response to DATA. If we have not had any good recipients, either
943 previously or in this block, the response is ignored. */
944
945 if (pending_DATA != 0 &&
946 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
947 {
948 int code;
949 uschar *msg;
950 BOOL pass_message;
951 if (pending_DATA > 0 || (yield & 1) != 0)
952 {
953 if (errno == 0 && buffer[0] == '4')
954 {
955 errno = ERRNO_DATA4XX;
956 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
957 }
958 return -3;
959 }
960 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
961 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
962 "is in use and there were no good recipients\n", msg);
963 }
964
965 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
966 present) received 3xx. If any RCPTs were handled and yielded anything other
967 than 4xx, yield will be set non-zero. */
968
969 return yield;
970 }
971
972
973
974 /* Do the client side of smtp-level authentication */
975 /*
976 Arguments:
977 buffer EHLO response from server (gets overwritten)
978 addrlist chain of potential addresses to deliver
979 host host to deliver to
980 ob transport options
981 ibp, obp comms channel control blocks
982
983 Returns:
984 OK Success, or failed (but not required): global "smtp_authenticated" set
985 DEFER Failed authentication (and was required)
986 ERROR Internal problem
987
988 FAIL_SEND Failed communications - transmit
989 FAIL - response
990 */
991
992 int
993 smtp_auth(uschar *buffer, unsigned bufsize, address_item *addrlist, host_item *host,
994 smtp_transport_options_block *ob, BOOL is_esmtp,
995 smtp_inblock *ibp, smtp_outblock *obp)
996 {
997 int require_auth;
998 uschar *fail_reason = US"server did not advertise AUTH support";
999
1000 smtp_authenticated = FALSE;
1001 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
1002 require_auth = verify_check_given_host(&ob->hosts_require_auth, host);
1003
1004 if (is_esmtp && !regex_AUTH) regex_AUTH =
1005 regex_must_compile(US"\\n250[\\s\\-]AUTH\\s+([\\-\\w\\s]+)(?:\\n|$)",
1006 FALSE, TRUE);
1007
1008 if (is_esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
1009 {
1010 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
1011 expand_nmax = -1; /* reset */
1012
1013 /* Must not do this check until after we have saved the result of the
1014 regex match above. */
1015
1016 if (require_auth == OK ||
1017 verify_check_given_host(&ob->hosts_try_auth, host) == OK)
1018 {
1019 auth_instance *au;
1020 fail_reason = US"no common mechanisms were found";
1021
1022 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1023
1024 /* Scan the configured authenticators looking for one which is configured
1025 for use as a client, which is not suppressed by client_condition, and
1026 whose name matches an authentication mechanism supported by the server.
1027 If one is found, attempt to authenticate by calling its client function.
1028 */
1029
1030 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1031 {
1032 uschar *p = names;
1033 if (!au->client ||
1034 (au->client_condition != NULL &&
1035 !expand_check_condition(au->client_condition, au->name,
1036 US"client authenticator")))
1037 {
1038 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1039 au->name,
1040 (au->client)? "client_condition is false" :
1041 "not configured as a client");
1042 continue;
1043 }
1044
1045 /* Loop to scan supported server mechanisms */
1046
1047 while (*p != 0)
1048 {
1049 int rc;
1050 int len = Ustrlen(au->public_name);
1051 while (isspace(*p)) p++;
1052
1053 if (strncmpic(au->public_name, p, len) != 0 ||
1054 (p[len] != 0 && !isspace(p[len])))
1055 {
1056 while (*p != 0 && !isspace(*p)) p++;
1057 continue;
1058 }
1059
1060 /* Found data for a listed mechanism. Call its client entry. Set
1061 a flag in the outblock so that data is overwritten after sending so
1062 that reflections don't show it. */
1063
1064 fail_reason = US"authentication attempt(s) failed";
1065 obp->authenticating = TRUE;
1066 rc = (au->info->clientcode)(au, ibp, obp,
1067 ob->command_timeout, buffer, bufsize);
1068 obp->authenticating = FALSE;
1069 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1070 au->name, rc);
1071
1072 /* A temporary authentication failure must hold up delivery to
1073 this host. After a permanent authentication failure, we carry on
1074 to try other authentication methods. If all fail hard, try to
1075 deliver the message unauthenticated unless require_auth was set. */
1076
1077 switch(rc)
1078 {
1079 case OK:
1080 smtp_authenticated = TRUE; /* stops the outer loop */
1081 client_authenticator = au->name;
1082 if (au->set_client_id != NULL)
1083 client_authenticated_id = expand_string(au->set_client_id);
1084 break;
1085
1086 /* Failure after writing a command */
1087
1088 case FAIL_SEND:
1089 return FAIL_SEND;
1090
1091 /* Failure after reading a response */
1092
1093 case FAIL:
1094 if (errno != 0 || buffer[0] != '5') return FAIL;
1095 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1096 au->name, host->name, host->address, buffer);
1097 break;
1098
1099 /* Failure by some other means. In effect, the authenticator
1100 decided it wasn't prepared to handle this case. Typically this
1101 is the result of "fail" in an expansion string. Do we need to
1102 log anything here? Feb 2006: a message is now put in the buffer
1103 if logging is required. */
1104
1105 case CANCELLED:
1106 if (*buffer != 0)
1107 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1108 "authentication H=%s [%s] %s", au->name, host->name,
1109 host->address, buffer);
1110 break;
1111
1112 /* Internal problem, message in buffer. */
1113
1114 case ERROR:
1115 set_errno_nohost(addrlist, ERRNO_AUTHPROB, string_copy(buffer),
1116 DEFER, FALSE);
1117 return ERROR;
1118 }
1119
1120 break; /* If not authenticated, try next authenticator */
1121 } /* Loop for scanning supported server mechanisms */
1122 } /* Loop for further authenticators */
1123 }
1124 }
1125
1126 /* If we haven't authenticated, but are required to, give up. */
1127
1128 if (require_auth == OK && !smtp_authenticated)
1129 {
1130 set_errno_nohost(addrlist, ERRNO_AUTHFAIL,
1131 string_sprintf("authentication required but %s", fail_reason), DEFER,
1132 FALSE);
1133 return DEFER;
1134 }
1135
1136 return OK;
1137 }
1138
1139
1140 /* Construct AUTH appendix string for MAIL TO */
1141 /*
1142 Arguments
1143 buffer to build string
1144 addrlist chain of potential addresses to deliver
1145 ob transport options
1146
1147 Globals smtp_authenticated
1148 client_authenticated_sender
1149 Return True on error, otherwise buffer has (possibly empty) terminated string
1150 */
1151
1152 BOOL
1153 smtp_mail_auth_str(uschar *buffer, unsigned bufsize, address_item *addrlist,
1154 smtp_transport_options_block *ob)
1155 {
1156 uschar *local_authenticated_sender = authenticated_sender;
1157
1158 #ifdef notdef
1159 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n", authenticated_sender, ob->authenticated_sender, smtp_authenticated?"Y":"N");
1160 #endif
1161
1162 if (ob->authenticated_sender != NULL)
1163 {
1164 uschar *new = expand_string(ob->authenticated_sender);
1165 if (new == NULL)
1166 {
1167 if (!expand_string_forcedfail)
1168 {
1169 uschar *message = string_sprintf("failed to expand "
1170 "authenticated_sender: %s", expand_string_message);
1171 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1172 return TRUE;
1173 }
1174 }
1175 else if (new[0] != 0) local_authenticated_sender = new;
1176 }
1177
1178 /* Add the authenticated sender address if present */
1179
1180 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1181 local_authenticated_sender != NULL)
1182 {
1183 string_format(buffer, bufsize, " AUTH=%s",
1184 auth_xtextencode(local_authenticated_sender,
1185 Ustrlen(local_authenticated_sender)));
1186 client_authenticated_sender = string_copy(local_authenticated_sender);
1187 }
1188 else
1189 *buffer= 0;
1190
1191 return FALSE;
1192 }
1193
1194
1195
1196 #ifdef EXPERIMENTAL_DANE
1197 /* Lookup TLSA record for host/port.
1198 Return: OK success with dnssec; DANE mode
1199 DEFER Do not use this host now, may retry later
1200 FAIL_FORCED No TLSA record; DANE not usable
1201 FAIL Do not use this connection
1202 */
1203
1204 int
1205 tlsa_lookup(const host_item * host, dns_answer * dnsa, BOOL dane_required)
1206 {
1207 /* move this out to host.c given the similarity to dns_lookup() ? */
1208 uschar buffer[300];
1209 const uschar * fullname = buffer;
1210
1211 /* TLSA lookup string */
1212 (void)sprintf(CS buffer, "_%d._tcp.%.256s", host->port, host->name);
1213
1214 switch (dns_lookup(dnsa, buffer, T_TLSA, &fullname))
1215 {
1216 case DNS_SUCCEED:
1217 if (!dns_is_secure(dnsa))
1218 {
1219 log_write(0, LOG_MAIN, "DANE error: TLSA lookup not DNSSEC");
1220 return DEFER;
1221 }
1222 return OK;
1223
1224 case DNS_AGAIN:
1225 return DEFER; /* just defer this TLS'd conn */
1226
1227 case DNS_NODATA: /* no TLSA RR for this lookup */
1228 case DNS_NOMATCH: /* no records at all for this lookup */
1229 return dane_required ? FAIL : FAIL_FORCED;
1230
1231 default:
1232 case DNS_FAIL:
1233 return dane_required ? FAIL : DEFER;
1234 }
1235 }
1236 #endif
1237
1238
1239
1240 typedef struct smtp_compare_s
1241 {
1242 uschar *current_sender_address;
1243 struct transport_instance *tblock;
1244 } smtp_compare_t;
1245
1246 /*
1247 Create a unique string that identifies this message, it is based on
1248 sender_address, helo_data and tls_certificate if enabled. */
1249
1250 static uschar *
1251 smtp_local_identity(uschar * sender, struct transport_instance * tblock)
1252 {
1253 address_item * addr1;
1254 uschar * if1 = US"";
1255 uschar * helo1 = US"";
1256 #ifdef SUPPORT_TLS
1257 uschar * tlsc1 = US"";
1258 #endif
1259 uschar * save_sender_address = sender_address;
1260 uschar * local_identity = NULL;
1261 smtp_transport_options_block * ob =
1262 (smtp_transport_options_block *)tblock->options_block;
1263
1264 sender_address = sender;
1265
1266 addr1 = deliver_make_addr (sender, TRUE);
1267 deliver_set_expansions(addr1);
1268
1269 if (ob->interface)
1270 if1 = expand_string(ob->interface);
1271
1272 if (ob->helo_data)
1273 helo1 = expand_string(ob->helo_data);
1274
1275 #ifdef SUPPORT_TLS
1276 if (ob->tls_certificate)
1277 tlsc1 = expand_string(ob->tls_certificate);
1278 local_identity = string_sprintf ("%s^%s^%s", if1, helo1, tlsc1);
1279 #else
1280 local_identity = string_sprintf ("%s^%s", if1, helo1);
1281 #endif
1282
1283 deliver_set_expansions(NULL);
1284 sender_address = save_sender_address;
1285
1286 return local_identity;
1287 }
1288
1289
1290
1291 /* This routine is a callback that is called from transport_check_waiting.
1292 This function will evaluate the incoming message versus the previous
1293 message. If the incoming message is using a different local identity then
1294 we will veto this new message. */
1295
1296 static BOOL
1297 smtp_are_same_identities(uschar * message_id, smtp_compare_t * s_compare)
1298 {
1299 uschar * message_local_identity,
1300 * current_local_identity,
1301 * new_sender_address;
1302
1303 current_local_identity =
1304 smtp_local_identity(s_compare->current_sender_address, s_compare->tblock);
1305
1306 if (!(new_sender_address = deliver_get_sender_address(message_id)))
1307 return 0;
1308
1309 message_local_identity =
1310 smtp_local_identity(new_sender_address, s_compare->tblock);
1311
1312 return Ustrcmp(current_local_identity, message_local_identity) == 0;
1313 }
1314
1315
1316
1317 uschar
1318 ehlo_response(uschar * buf, size_t bsize, uschar checks)
1319 {
1320 #ifdef SUPPORT_TLS
1321 if ( checks & PEER_OFFERED_TLS
1322 && pcre_exec(regex_STARTTLS, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1323 checks &= ~PEER_OFFERED_TLS;
1324 #endif
1325
1326 if ( checks & PEER_OFFERED_IGNQ
1327 && pcre_exec(regex_IGNOREQUOTA, NULL, CS buf, bsize, 0,
1328 PCRE_EOPT, NULL, 0) < 0)
1329 checks &= ~PEER_OFFERED_IGNQ;
1330
1331 if ( checks & PEER_OFFERED_CHUNKING
1332 && pcre_exec(regex_CHUNKING, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1333 checks &= ~PEER_OFFERED_CHUNKING;
1334
1335 #ifndef DISABLE_PRDR
1336 if ( checks & PEER_OFFERED_PRDR
1337 && pcre_exec(regex_PRDR, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1338 checks &= ~PEER_OFFERED_PRDR;
1339 #endif
1340
1341 #ifdef SUPPORT_I18N
1342 if ( checks & PEER_OFFERED_UTF8
1343 && pcre_exec(regex_UTF8, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1344 checks &= ~PEER_OFFERED_UTF8;
1345 #endif
1346
1347 if ( checks & PEER_OFFERED_DSN
1348 && pcre_exec(regex_DSN, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1349 checks &= ~PEER_OFFERED_DSN;
1350
1351 if ( checks & PEER_OFFERED_PIPE
1352 && pcre_exec(regex_PIPELINING, NULL, CS buf, bsize, 0,
1353 PCRE_EOPT, NULL, 0) < 0)
1354 checks &= ~PEER_OFFERED_PIPE;
1355
1356 if ( checks & PEER_OFFERED_SIZE
1357 && pcre_exec(regex_SIZE, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1358 checks &= ~PEER_OFFERED_SIZE;
1359
1360 return checks;
1361 }
1362
1363
1364
1365 /* Callback for emitting a BDAT data chunk header.
1366
1367 If given a nonzero size, first flush any buffered SMTP commands
1368 then emit the command.
1369
1370 Reap previous SMTP command responses if requested.
1371 Reap one SMTP command response if requested.
1372
1373 Returns: OK or ERROR
1374 */
1375
1376 static int
1377 smtp_chunk_cmd_callback(int fd, transport_ctx * tctx,
1378 unsigned chunk_size, unsigned flags)
1379 {
1380 smtp_transport_options_block * ob =
1381 (smtp_transport_options_block *)(tctx->tblock->options_block);
1382 int cmd_count = 0;
1383 int prev_cmd_count;
1384 uschar * buffer = tctx->buffer;
1385
1386
1387 /* Write SMTP chunk header command */
1388
1389 if (chunk_size > 0)
1390 if((cmd_count = smtp_write_command(tctx->outblock, FALSE, "BDAT %u%s\r\n",
1391 chunk_size,
1392 flags & tc_chunk_last ? " LAST" : "")
1393 ) < 0) return ERROR;
1394
1395 prev_cmd_count = cmd_count += tctx->cmd_count;
1396
1397 /* Reap responses for any previous, but not one we just emitted */
1398
1399 if (chunk_size > 0)
1400 prev_cmd_count--;
1401 if (tctx->pending_BDAT)
1402 prev_cmd_count--;
1403
1404 if (flags & tc_reap_prev && prev_cmd_count > 0)
1405 {
1406 DEBUG(D_transport) debug_printf("look for %d responses"
1407 " for previous pipelined cmds\n", prev_cmd_count);
1408
1409 switch(sync_responses(tctx->first_addr, tctx->tblock->rcpt_include_affixes,
1410 tctx->sync_addr, tctx->host, prev_cmd_count,
1411 ob->address_retry_include_sender,
1412 tctx->pending_MAIL, 0,
1413 tctx->inblock,
1414 ob->command_timeout,
1415 buffer, DELIVER_BUFFER_SIZE))
1416 {
1417 case 1: /* 2xx (only) => OK */
1418 case 3: tctx->good_RCPT = TRUE; /* 2xx & 5xx => OK & progress made */
1419 case 2: *tctx->completed_address = TRUE; /* 5xx (only) => progress made */
1420 case 0: break; /* No 2xx or 5xx, but no probs */
1421
1422 case -1: /* Timeout on RCPT */
1423 default: return ERROR; /* I/O error, or any MAIL/DATA error */
1424 }
1425 cmd_count = 1;
1426 if (!tctx->pending_BDAT)
1427 pipelining_active = FALSE;
1428 }
1429
1430 /* Reap response for an outstanding BDAT */
1431
1432 if (tctx->pending_BDAT)
1433 {
1434 DEBUG(D_transport) debug_printf("look for one response for BDAT\n");
1435
1436 if (!smtp_read_response(tctx->inblock, buffer, DELIVER_BUFFER_SIZE, '2',
1437 ob->command_timeout))
1438 {
1439 if (errno == 0 && buffer[0] == '4')
1440 {
1441 errno = ERRNO_DATA4XX; /*XXX does this actually get used? */
1442 tctx->first_addr->more_errno |=
1443 ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1444 }
1445 return ERROR;
1446 }
1447 cmd_count--;
1448 tctx->pending_BDAT = FALSE;
1449 pipelining_active = FALSE;
1450 }
1451 else if (chunk_size > 0)
1452 tctx->pending_BDAT = TRUE;
1453
1454
1455 tctx->cmd_count = cmd_count;
1456 return OK;
1457 }
1458
1459
1460
1461 /*************************************************
1462 * Deliver address list to given host *
1463 *************************************************/
1464
1465 /* If continue_hostname is not null, we get here only when continuing to
1466 deliver down an existing channel. The channel was passed as the standard
1467 input. TLS is never active on a passed channel; the previous process always
1468 closes it down before passing the connection on.
1469
1470 Otherwise, we have to make a connection to the remote host, and do the
1471 initial protocol exchange.
1472
1473 When running as an MUA wrapper, if the sender or any recipient is rejected,
1474 temporarily or permanently, we force failure for all recipients.
1475
1476 Arguments:
1477 addrlist chain of potential addresses to deliver; only those whose
1478 transport_return field is set to PENDING_DEFER are currently
1479 being processed; others should be skipped - they have either
1480 been delivered to an earlier host or IP address, or been
1481 failed by one of them.
1482 host host to deliver to
1483 host_af AF_INET or AF_INET6
1484 port default TCP/IP port to use, in host byte order
1485 interface interface to bind to, or NULL
1486 tblock transport instance block
1487 message_defer set TRUE if yield is OK, but all addresses were deferred
1488 because of a non-recipient, non-host failure, that is, a
1489 4xx response to MAIL FROM, DATA, or ".". This is a defer
1490 that is specific to the message.
1491 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1492 a second attempt after TLS initialization fails
1493
1494 Returns: OK - the connection was made and the delivery attempted;
1495 the result for each address is in its data block.
1496 DEFER - the connection could not be made, or something failed
1497 while setting up the SMTP session, or there was a
1498 non-message-specific error, such as a timeout.
1499 ERROR - a filter command is specified for this transport,
1500 and there was a problem setting it up; OR helo_data
1501 or add_headers or authenticated_sender is specified
1502 for this transport, and the string failed to expand
1503 */
1504
1505 static int
1506 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
1507 uschar *interface, transport_instance *tblock,
1508 BOOL *message_defer, BOOL suppress_tls)
1509 {
1510 address_item *addr;
1511 address_item *sync_addr;
1512 address_item *first_addr = addrlist;
1513 int yield = OK;
1514 int address_count;
1515 int save_errno;
1516 int rc;
1517 time_t start_delivery_time = time(NULL);
1518 smtp_transport_options_block *ob =
1519 (smtp_transport_options_block *)(tblock->options_block);
1520 struct lflags {
1521 BOOL lmtp:1;
1522 BOOL smtps:1;
1523 BOOL ok:1;
1524 BOOL send_rset:1;
1525 BOOL send_quit:1;
1526 BOOL setting_up:1;
1527 BOOL esmtp:1;
1528 BOOL esmtp_sent:1;
1529 BOOL pending_MAIL:1;
1530 #ifndef DISABLE_PRDR
1531 BOOL prdr_active:1;
1532 #endif
1533 #ifdef SUPPORT_I18N
1534 BOOL utf8_needed:1;
1535 #endif
1536 BOOL dsn_all_lasthop:1;
1537 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1538 BOOL dane:1;
1539 BOOL dane_required:1;
1540 #endif
1541 } lflags;
1542
1543 BOOL pass_message = FALSE;
1544 BOOL completed_address = FALSE;
1545 uschar peer_offered = 0;
1546 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1547 dns_answer tlsa_dnsa;
1548 #endif
1549 smtp_inblock inblock;
1550 smtp_outblock outblock;
1551 int max_rcpt = tblock->max_addresses;
1552 uschar *igquotstr = US"";
1553
1554 #ifdef EXPERIMENTAL_DSN_INFO
1555 uschar *smtp_greeting = NULL;
1556 uschar *helo_response = NULL;
1557 #endif
1558 uschar *helo_data = NULL;
1559
1560 uschar *message = NULL;
1561 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
1562 uschar *p;
1563 uschar buffer[DELIVER_BUFFER_SIZE];
1564 uschar inbuffer[4096];
1565 uschar outbuffer[4096];
1566
1567 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
1568
1569 lflags.lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
1570 lflags.smtps = strcmpic(ob->protocol, US"smtps") == 0;
1571 lflags.ok = FALSE;
1572 lflags.send_rset = TRUE;
1573 lflags.send_quit = TRUE;
1574 lflags.setting_up = TRUE;
1575 lflags.esmtp = TRUE;
1576 lflags.esmtp_sent = FALSE;
1577 #ifndef DISABLE_PRDR
1578 lflags.prdr_active;
1579 #endif
1580 #ifdef SUPPORT_I18N
1581 lflags.utf8_needed = FALSE;
1582 #endif
1583 lflags.dsn_all_lasthop = TRUE;
1584 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1585 lflags.dane = FALSE;
1586 lflags.dane_required = verify_check_given_host(&ob->hosts_require_dane, host) == OK;
1587 #endif
1588
1589 *message_defer = FALSE;
1590 smtp_command = US"initial connection";
1591 if (max_rcpt == 0) max_rcpt = 999999;
1592
1593 /* Set up the buffer for reading SMTP response packets. */
1594
1595 inblock.buffer = inbuffer;
1596 inblock.buffersize = sizeof(inbuffer);
1597 inblock.ptr = inbuffer;
1598 inblock.ptrend = inbuffer;
1599
1600 /* Set up the buffer for holding SMTP commands while pipelining */
1601
1602 outblock.buffer = outbuffer;
1603 outblock.buffersize = sizeof(outbuffer);
1604 outblock.ptr = outbuffer;
1605 outblock.cmd_count = 0;
1606 outblock.authenticating = FALSE;
1607
1608 /* Reset the parameters of a TLS session. */
1609
1610 tls_out.bits = 0;
1611 tls_out.cipher = NULL; /* the one we may use for this transport */
1612 tls_out.ourcert = NULL;
1613 tls_out.peercert = NULL;
1614 tls_out.peerdn = NULL;
1615 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1616 tls_out.sni = NULL;
1617 #endif
1618 tls_out.ocsp = OCSP_NOT_REQ;
1619
1620 /* Flip the legacy TLS-related variables over to the outbound set in case
1621 they're used in the context of the transport. Don't bother resetting
1622 afterward as we're in a subprocess. */
1623
1624 tls_modify_variables(&tls_out);
1625
1626 #ifndef SUPPORT_TLS
1627 if (lflags.smtps)
1628 {
1629 set_errno_nohost(addrlist, ERRNO_TLSFAILURE, US"TLS support not available",
1630 DEFER, FALSE);
1631 return ERROR;
1632 }
1633 #endif
1634
1635 /* Make a connection to the host if this isn't a continued delivery, and handle
1636 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
1637 specially so they can be identified for retries. */
1638
1639 if (continue_hostname == NULL)
1640 {
1641 /* This puts port into host->port */
1642 inblock.sock = outblock.sock =
1643 smtp_connect(host, host_af, port, interface, ob->connect_timeout, tblock);
1644
1645 if (inblock.sock < 0)
1646 {
1647 set_errno_nohost(addrlist, errno == ETIMEDOUT ? ERRNO_CONNECTTIMEOUT : errno,
1648 NULL, DEFER, FALSE);
1649 return DEFER;
1650 }
1651
1652 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1653 {
1654 tls_out.dane_verified = FALSE;
1655 tls_out.tlsa_usage = 0;
1656
1657 if (host->dnssec == DS_YES)
1658 {
1659 if( lflags.dane_required
1660 || verify_check_given_host(&ob->hosts_try_dane, host) == OK
1661 )
1662 switch (rc = tlsa_lookup(host, &tlsa_dnsa, lflags.dane_required))
1663 {
1664 case OK: lflags.dane = TRUE; break;
1665 case FAIL_FORCED: break;
1666 default: set_errno_nohost(addrlist, ERRNO_DNSDEFER,
1667 string_sprintf("DANE error: tlsa lookup %s",
1668 rc == DEFER ? "DEFER" : "FAIL"),
1669 rc, FALSE);
1670 return rc;
1671 }
1672 }
1673 else if (lflags.dane_required)
1674 {
1675 set_errno_nohost(addrlist, ERRNO_DNSDEFER,
1676 string_sprintf("DANE error: %s lookup not DNSSEC", host->name),
1677 FAIL, FALSE);
1678 return FAIL;
1679 }
1680
1681 if (lflags.dane)
1682 ob->tls_tempfail_tryclear = FALSE;
1683 }
1684 #endif /*DANE*/
1685
1686 /* Expand the greeting message while waiting for the initial response. (Makes
1687 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1688 delayed till here so that $sending_interface and $sending_port are set. */
1689
1690 helo_data = expand_string(ob->helo_data);
1691 #ifdef SUPPORT_I18N
1692 if (helo_data)
1693 {
1694 uschar * errstr = NULL;
1695 if ((helo_data = string_domain_utf8_to_alabel(helo_data, &errstr)), errstr)
1696 {
1697 errstr = string_sprintf("failed to expand helo_data: %s", errstr);
1698 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE);
1699 yield = DEFER;
1700 goto SEND_QUIT;
1701 }
1702 }
1703 #endif
1704
1705 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1706 is nevertheless a reasonably clean way of programming this kind of logic,
1707 where you want to escape on any error. */
1708
1709 if (!lflags.smtps)
1710 {
1711 BOOL good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
1712 '2', ob->command_timeout);
1713 #ifdef EXPERIMENTAL_DSN_INFO
1714 smtp_greeting = string_copy(buffer);
1715 #endif
1716 if (!good_response) goto RESPONSE_FAILED;
1717
1718 #ifndef DISABLE_EVENT
1719 {
1720 uschar * s;
1721 lookup_dnssec_authenticated = host->dnssec==DS_YES ? US"yes"
1722 : host->dnssec==DS_NO ? US"no" : NULL;
1723 s = event_raise(tblock->event_action, US"smtp:connect", buffer);
1724 if (s)
1725 {
1726 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL,
1727 string_sprintf("deferred by smtp:connect event expansion: %s", s),
1728 DEFER, FALSE);
1729 yield = DEFER;
1730 goto SEND_QUIT;
1731 }
1732 }
1733 #endif
1734
1735 /* Now check if the helo_data expansion went well, and sign off cleanly if
1736 it didn't. */
1737
1738 if (helo_data == NULL)
1739 {
1740 uschar *message = string_sprintf("failed to expand helo_data: %s",
1741 expand_string_message);
1742 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1743 yield = DEFER;
1744 goto SEND_QUIT;
1745 }
1746 }
1747
1748 /** Debugging without sending a message
1749 addrlist->transport_return = DEFER;
1750 goto SEND_QUIT;
1751 **/
1752
1753 /* Errors that occur after this point follow an SMTP command, which is
1754 left in big_buffer by smtp_write_command() for use in error messages. */
1755
1756 smtp_command = big_buffer;
1757
1758 /* Tell the remote who we are...
1759
1760 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1761 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1762 greeting is of this form. The assumption was that the far end supports it
1763 properly... but experience shows that there are some that give 5xx responses,
1764 even though the banner includes "ESMTP" (there's a bloody-minded one that
1765 says "ESMTP not spoken here"). Cope with that case.
1766
1767 September 2000: Time has passed, and it seems reasonable now to always send
1768 EHLO at the start. It is also convenient to make the change while installing
1769 the TLS stuff.
1770
1771 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1772 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1773 would be no way to send out the mails, so there is now a host list
1774 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1775 PIPELINING problem as well. Maybe it can also be useful to cure other
1776 problems with broken servers.
1777
1778 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1779 Then somebody tried it with a Microsoft mailer... It seems that all other
1780 mailers use upper case for some reason (the RFC is quite clear about case
1781 independence) so, for peace of mind, I gave in. */
1782
1783 lflags.esmtp = verify_check_given_host(&ob->hosts_avoid_esmtp, host) != OK;
1784
1785 /* Alas; be careful, since this goto is not an error-out, so conceivably
1786 we might set data between here and the target which we assume to exist
1787 and be usable. I can see this coming back to bite us. */
1788 #ifdef SUPPORT_TLS
1789 if (lflags.smtps)
1790 {
1791 smtp_peer_options |= PEER_OFFERED_TLS;
1792 suppress_tls = FALSE;
1793 ob->tls_tempfail_tryclear = FALSE;
1794 smtp_command = US"SSL-on-connect";
1795 goto TLS_NEGOTIATE;
1796 }
1797 #endif
1798
1799 if (lflags.esmtp)
1800 {
1801 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1802 lflags.lmtp ? "LHLO" : "EHLO", helo_data) < 0)
1803 goto SEND_FAILED;
1804 lflags.esmtp_sent = TRUE;
1805 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1806 ob->command_timeout))
1807 {
1808 if (errno != 0 || buffer[0] == 0 || lflags.lmtp)
1809 {
1810 #ifdef EXPERIMENTAL_DSN_INFO
1811 helo_response = string_copy(buffer);
1812 #endif
1813 goto RESPONSE_FAILED;
1814 }
1815 lflags.esmtp = FALSE;
1816 }
1817 #ifdef EXPERIMENTAL_DSN_INFO
1818 helo_response = string_copy(buffer);
1819 #endif
1820 }
1821 else
1822 DEBUG(D_transport)
1823 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1824
1825 if (!lflags.esmtp)
1826 {
1827 BOOL good_response;
1828 int n = sizeof(buffer);
1829 uschar * rsp = buffer;
1830
1831 if (lflags.esmtp_sent && (n = Ustrlen(buffer)) < sizeof(buffer)/2)
1832 { rsp = buffer + n + 1; n = sizeof(buffer) - n; }
1833
1834 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1835 goto SEND_FAILED;
1836 good_response = smtp_read_response(&inblock, rsp, n,
1837 '2', ob->command_timeout);
1838 #ifdef EXPERIMENTAL_DSN_INFO
1839 helo_response = string_copy(rsp);
1840 #endif
1841 if (!good_response)
1842 {
1843 /* Handle special logging for a closed connection after HELO
1844 when had previously sent EHLO */
1845
1846 if (rsp != buffer && rsp[0] == 0 && (errno == 0 || errno == ECONNRESET))
1847 {
1848 message = NULL;
1849 lflags.send_quit = FALSE;
1850 save_errno = ERRNO_SMTPCLOSED;
1851 message = string_sprintf("Remote host closed connection "
1852 "in response to %s (EHLO response was: %s)",
1853 smtp_command, buffer);
1854 goto FAILED;
1855 }
1856 Ustrncpy(buffer, rsp, sizeof(buffer)/2);
1857 goto RESPONSE_FAILED;
1858 }
1859 }
1860
1861 peer_offered = smtp_peer_options = 0;
1862
1863 if (lflags.esmtp || lflags.lmtp)
1864 {
1865 peer_offered = ehlo_response(buffer, Ustrlen(buffer),
1866 PEER_OFFERED_TLS /* others checked later */
1867 );
1868
1869 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1870
1871 #ifdef SUPPORT_TLS
1872 smtp_peer_options |= peer_offered & PEER_OFFERED_TLS;
1873 #endif
1874 }
1875 }
1876
1877 /* For continuing deliveries down the same channel, the socket is the standard
1878 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1879 below). Set up the pointer to where subsequent commands will be left, for
1880 error messages. Note that smtp_peer_options will have been
1881 set from the command line if they were set in the process that passed the
1882 connection on. */
1883
1884 /*XXX continue case needs to propagate DSN_INFO, prob. in deliver.c
1885 as the contine goes via transport_pass_socket() and doublefork and exec.
1886 It does not wait. Unclear how we keep separate host's responses
1887 separate - we could match up by host ip+port as a bodge. */
1888
1889 else
1890 {
1891 inblock.sock = outblock.sock = fileno(stdin);
1892 smtp_command = big_buffer;
1893 host->port = port; /* Record the port that was used */
1894 }
1895
1896 /* If TLS is available on this connection, whether continued or not, attempt to
1897 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1898 send another EHLO - the server may give a different answer in secure mode. We
1899 use a separate buffer for reading the response to STARTTLS so that if it is
1900 negative, the original EHLO data is available for subsequent analysis, should
1901 the client not be required to use TLS. If the response is bad, copy the buffer
1902 for error analysis. */
1903
1904 #ifdef SUPPORT_TLS
1905 if ( smtp_peer_options & PEER_OFFERED_TLS
1906 && !suppress_tls
1907 && verify_check_given_host(&ob->hosts_avoid_tls, host) != OK)
1908 {
1909 uschar buffer2[4096];
1910 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1911 goto SEND_FAILED;
1912
1913 /* If there is an I/O error, transmission of this message is deferred. If
1914 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1915 false, we also defer. However, if there is a temporary rejection of STARTTLS
1916 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1917 STARTTLS, we carry on. This means we will try to send the message in clear,
1918 unless the host is in hosts_require_tls (tested below). */
1919
1920 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1921 ob->command_timeout))
1922 {
1923 if ( errno != 0
1924 || buffer2[0] == 0
1925 || (buffer2[0] == '4' && !ob->tls_tempfail_tryclear)
1926 )
1927 {
1928 Ustrncpy(buffer, buffer2, sizeof(buffer));
1929 goto RESPONSE_FAILED;
1930 }
1931 }
1932
1933 /* STARTTLS accepted: try to negotiate a TLS session. */
1934
1935 else
1936 TLS_NEGOTIATE:
1937 {
1938 int rc = tls_client_start(inblock.sock, host, addrlist, tblock
1939 # ifdef EXPERIMENTAL_DANE
1940 , lflags.dane ? &tlsa_dnsa : NULL
1941 # endif
1942 );
1943
1944 /* TLS negotiation failed; give an error. From outside, this function may
1945 be called again to try in clear on a new connection, if the options permit
1946 it for this host. */
1947
1948 if (rc != OK)
1949 {
1950 # ifdef EXPERIMENTAL_DANE
1951 if (rc == DEFER && lflags.dane)
1952 {
1953 log_write(0, LOG_MAIN,
1954 "DANE attempt failed; no TLS connection to %s [%s]",
1955 host->name, host->address);
1956 }
1957 # endif
1958
1959 save_errno = ERRNO_TLSFAILURE;
1960 message = US"failure while setting up TLS session";
1961 lflags.send_quit = FALSE;
1962 goto TLS_FAILED;
1963 }
1964
1965 /* TLS session is set up */
1966
1967 smtp_peer_options_wrap = smtp_peer_options;
1968 for (addr = addrlist; addr; addr = addr->next)
1969 if (addr->transport_return == PENDING_DEFER)
1970 {
1971 addr->cipher = tls_out.cipher;
1972 addr->ourcert = tls_out.ourcert;
1973 addr->peercert = tls_out.peercert;
1974 addr->peerdn = tls_out.peerdn;
1975 addr->ocsp = tls_out.ocsp;
1976 }
1977 }
1978 }
1979
1980 /* if smtps, we'll have smtp_command set to something else; always safe to
1981 reset it here. */
1982 smtp_command = big_buffer;
1983
1984 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1985 helo_data is null, we are dealing with a connection that was passed from
1986 another process, and so we won't have expanded helo_data above. We have to
1987 expand it here. $sending_ip_address and $sending_port are set up right at the
1988 start of the Exim process (in exim.c). */
1989
1990 if (tls_out.active >= 0)
1991 {
1992 char *greeting_cmd;
1993 BOOL good_response;
1994
1995 if (helo_data == NULL)
1996 {
1997 helo_data = expand_string(ob->helo_data);
1998 if (helo_data == NULL)
1999 {
2000 uschar *message = string_sprintf("failed to expand helo_data: %s",
2001 expand_string_message);
2002 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
2003 yield = DEFER;
2004 goto SEND_QUIT;
2005 }
2006 }
2007
2008 /* For SMTPS we need to wait for the initial OK response. */
2009 if (lflags.smtps)
2010 {
2011 good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
2012 '2', ob->command_timeout);
2013 #ifdef EXPERIMENTAL_DSN_INFO
2014 smtp_greeting = string_copy(buffer);
2015 #endif
2016 if (!good_response) goto RESPONSE_FAILED;
2017 }
2018
2019 if (lflags.esmtp)
2020 greeting_cmd = "EHLO";
2021 else
2022 {
2023 greeting_cmd = "HELO";
2024 DEBUG(D_transport)
2025 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
2026 }
2027
2028 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
2029 lflags.lmtp ? "LHLO" : greeting_cmd, helo_data) < 0)
2030 goto SEND_FAILED;
2031 good_response = smtp_read_response(&inblock, buffer, sizeof(buffer),
2032 '2', ob->command_timeout);
2033 #ifdef EXPERIMENTAL_DSN_INFO
2034 helo_response = string_copy(buffer);
2035 #endif
2036 if (!good_response) goto RESPONSE_FAILED;
2037 smtp_peer_options = 0;
2038 }
2039
2040 /* If the host is required to use a secure channel, ensure that we
2041 have one. */
2042
2043 else if ( lflags.smtps
2044 # ifdef EXPERIMENTAL_DANE
2045 || lflags.dane
2046 # endif
2047 || verify_check_given_host(&ob->hosts_require_tls, host) == OK
2048 )
2049 {
2050 save_errno = ERRNO_TLSREQUIRED;
2051 message = string_sprintf("a TLS session is required, but %s",
2052 smtp_peer_options & PEER_OFFERED_TLS
2053 ? "an attempt to start TLS failed" : "the server did not offer TLS support");
2054 goto TLS_FAILED;
2055 }
2056 #endif /*SUPPORT_TLS*/
2057
2058 /* If TLS is active, we have just started it up and re-done the EHLO command,
2059 so its response needs to be analyzed. If TLS is not active and this is a
2060 continued session down a previously-used socket, we haven't just done EHLO, so
2061 we skip this. */
2062
2063 if (continue_hostname == NULL
2064 #ifdef SUPPORT_TLS
2065 || tls_out.active >= 0
2066 #endif
2067 )
2068 {
2069 if (lflags.esmtp || lflags.lmtp)
2070 {
2071 peer_offered = ehlo_response(buffer, Ustrlen(buffer),
2072 0 /* no TLS */
2073 | (lflags.lmtp && ob->lmtp_ignore_quota ? PEER_OFFERED_IGNQ : 0)
2074 | PEER_OFFERED_CHUNKING
2075 | PEER_OFFERED_PRDR
2076 #ifdef SUPPORT_I18N
2077 | (addrlist->prop.utf8_msg ? PEER_OFFERED_UTF8 : 0)
2078 /*XXX if we hand peercaps on to continued-conn processes,
2079 must not depend on this addr */
2080 #endif
2081 | PEER_OFFERED_DSN
2082 | PEER_OFFERED_PIPE
2083 | (ob->size_addition >= 0 ? PEER_OFFERED_SIZE : 0)
2084 );
2085
2086 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
2087 lmtp_ignore_quota option was set. */
2088
2089 igquotstr = peer_offered & PEER_OFFERED_IGNQ ? US" IGNOREQUOTA" : US"";
2090
2091 /* If the response to EHLO specified support for the SIZE parameter, note
2092 this, provided size_addition is non-negative. */
2093
2094 smtp_peer_options |= peer_offered & PEER_OFFERED_SIZE;
2095
2096 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
2097 the current host, esmtp will be false, so PIPELINING can never be used. If
2098 the current host matches hosts_avoid_pipelining, don't do it. */
2099
2100 if ( peer_offered & PEER_OFFERED_PIPE
2101 && verify_check_given_host(&ob->hosts_avoid_pipelining, host) != OK)
2102 smtp_peer_options |= PEER_OFFERED_PIPE;
2103
2104 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
2105 smtp_peer_options & PEER_OFFERED_PIPE ? "" : "not ");
2106
2107 if ( peer_offered & PEER_OFFERED_CHUNKING
2108 && verify_check_given_host(&ob->hosts_try_chunking, host) != OK)
2109 peer_offered &= ~PEER_OFFERED_CHUNKING;
2110
2111 if (peer_offered & PEER_OFFERED_CHUNKING)
2112 {DEBUG(D_transport) debug_printf("CHUNKING usable\n");}
2113
2114 #ifndef DISABLE_PRDR
2115 if ( peer_offered & PEER_OFFERED_PRDR
2116 && verify_check_given_host(&ob->hosts_try_prdr, host) != OK)
2117 peer_offered &= ~PEER_OFFERED_PRDR;
2118
2119 if (peer_offered & PEER_OFFERED_PRDR)
2120 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
2121 #endif
2122
2123 /* Note if the server supports DSN */
2124 smtp_peer_options |= peer_offered & PEER_OFFERED_DSN;
2125 DEBUG(D_transport) debug_printf("%susing DSN\n",
2126 peer_offered & PEER_OFFERED_DSN ? "" : "not ");
2127
2128 /* Note if the response to EHLO specifies support for the AUTH extension.
2129 If it has, check that this host is one we want to authenticate to, and do
2130 the business. The host name and address must be available when the
2131 authenticator's client driver is running. */
2132
2133 switch (yield = smtp_auth(buffer, sizeof(buffer), addrlist, host,
2134 ob, lflags.esmtp, &inblock, &outblock))
2135 {
2136 default: goto SEND_QUIT;
2137 case OK: break;
2138 case FAIL_SEND: goto SEND_FAILED;
2139 case FAIL: goto RESPONSE_FAILED;
2140 }
2141 }
2142 }
2143 pipelining_active = !!(smtp_peer_options & PEER_OFFERED_PIPE);
2144
2145 /* The setting up of the SMTP call is now complete. Any subsequent errors are
2146 message-specific. */
2147
2148 lflags.setting_up = FALSE;
2149
2150 #ifdef SUPPORT_I18N
2151 if (addrlist->prop.utf8_msg)
2152 {
2153 lflags.utf8_needed = !addrlist->prop.utf8_downcvt
2154 && !addrlist->prop.utf8_downcvt_maybe;
2155 DEBUG(D_transport) if (!lflags.utf8_needed)
2156 debug_printf("utf8: %s downconvert\n",
2157 addrlist->prop.utf8_downcvt ? "mandatory" : "optional");
2158 }
2159
2160 /* If this is an international message we need the host to speak SMTPUTF8 */
2161 if (lflags.utf8_needed && !(peer_offered & PEER_OFFERED_UTF8))
2162 {
2163 errno = ERRNO_UTF8_FWD;
2164 goto RESPONSE_FAILED;
2165 }
2166 #endif
2167
2168 /* If there is a filter command specified for this transport, we can now
2169 set it up. This cannot be done until the identify of the host is known. */
2170
2171 if (tblock->filter_command != NULL)
2172 {
2173 BOOL rc;
2174 uschar buffer[64];
2175 sprintf(CS buffer, "%.50s transport", tblock->name);
2176 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
2177 TRUE, DEFER, addrlist, buffer, NULL);
2178 transport_filter_timeout = tblock->filter_timeout;
2179
2180 /* On failure, copy the error to all addresses, abandon the SMTP call, and
2181 yield ERROR. */
2182
2183 if (!rc)
2184 {
2185 set_errno_nohost(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
2186 FALSE);
2187 yield = ERROR;
2188 goto SEND_QUIT;
2189 }
2190
2191 if ( transport_filter_argv
2192 && *transport_filter_argv
2193 && **transport_filter_argv
2194 && peer_offered & PEER_OFFERED_CHUNKING
2195 )
2196 {
2197 peer_offered &= ~PEER_OFFERED_CHUNKING;
2198 DEBUG(D_transport) debug_printf("CHUNKING not usable due to transport filter\n");
2199 }
2200 }
2201
2202
2203 /* For messages that have more than the maximum number of envelope recipients,
2204 we want to send several transactions down the same SMTP connection. (See
2205 comments in deliver.c as to how this reconciles, heuristically, with
2206 remote_max_parallel.) This optimization was added to Exim after the following
2207 code was already working. The simplest way to put it in without disturbing the
2208 code was to use a goto to jump back to this point when there is another
2209 transaction to handle. */
2210
2211 SEND_MESSAGE:
2212 sync_addr = first_addr;
2213 address_count = 0;
2214 lflags.ok = FALSE;
2215 lflags.send_rset = TRUE;
2216 completed_address = FALSE;
2217
2218
2219 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
2220 qualification, send it, adding something to the message size to allow for
2221 imprecision and things that get added en route. Exim keeps the number of lines
2222 in a message, so we can give an accurate value for the original message, but we
2223 need some additional to handle added headers. (Double "." characters don't get
2224 included in the count.) */
2225
2226 p = buffer;
2227 *p = 0;
2228
2229 if (peer_offered & PEER_OFFERED_SIZE)
2230 {
2231 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
2232 while (*p) p++;
2233 }
2234
2235 #ifndef DISABLE_PRDR
2236 lflags.prdr_active = FALSE;
2237 if (peer_offered & PEER_OFFERED_PRDR)
2238 for (addr = first_addr; addr; addr = addr->next)
2239 if (addr->transport_return == PENDING_DEFER)
2240 {
2241 for (addr = addr->next; addr; addr = addr->next)
2242 if (addr->transport_return == PENDING_DEFER)
2243 { /* at least two recipients to send */
2244 lflags.prdr_active = TRUE;
2245 sprintf(CS p, " PRDR"); p += 5;
2246 break;
2247 }
2248 break;
2249 }
2250 #endif
2251
2252 #ifdef SUPPORT_I18N
2253 if ( addrlist->prop.utf8_msg
2254 && !addrlist->prop.utf8_downcvt
2255 && peer_offered & PEER_OFFERED_UTF8
2256 )
2257 sprintf(CS p, " SMTPUTF8"), p += 9;
2258 #endif
2259
2260 /* check if all addresses have lasthop flag */
2261 /* do not send RET and ENVID if true */
2262 for (lflags.dsn_all_lasthop = TRUE, addr = first_addr;
2263 address_count < max_rcpt && addr != NULL;
2264 addr = addr->next)
2265 if ((addr->dsn_flags & rf_dsnlasthop) != 1)
2266 {
2267 lflags.dsn_all_lasthop = FALSE;
2268 break;
2269 }
2270
2271 /* Add any DSN flags to the mail command */
2272
2273 if (peer_offered & PEER_OFFERED_DSN && !lflags.dsn_all_lasthop)
2274 {
2275 if (dsn_ret == dsn_ret_hdrs)
2276 { Ustrcpy(p, " RET=HDRS"); p += 9; }
2277 else if (dsn_ret == dsn_ret_full)
2278 { Ustrcpy(p, " RET=FULL"); p += 9; }
2279
2280 if (dsn_envid)
2281 {
2282 string_format(p, sizeof(buffer) - (p-buffer), " ENVID=%s", dsn_envid);
2283 while (*p) p++;
2284 }
2285 }
2286
2287 /* If an authenticated_sender override has been specified for this transport
2288 instance, expand it. If the expansion is forced to fail, and there was already
2289 an authenticated_sender for this message, the original value will be used.
2290 Other expansion failures are serious. An empty result is ignored, but there is
2291 otherwise no check - this feature is expected to be used with LMTP and other
2292 cases where non-standard addresses (e.g. without domains) might be required. */
2293
2294 if (smtp_mail_auth_str(p, sizeof(buffer) - (p-buffer), addrlist, ob))
2295 {
2296 yield = ERROR;
2297 goto SEND_QUIT;
2298 }
2299
2300 /* From here until we send the DATA command, we can make use of PIPELINING
2301 if the server host supports it. The code has to be able to check the responses
2302 at any point, for when the buffer fills up, so we write it totally generally.
2303 When PIPELINING is off, each command written reports that it has flushed the
2304 buffer. */
2305
2306 lflags.pending_MAIL = TRUE; /* The block starts with MAIL */
2307
2308 {
2309 uschar * s = return_path;
2310 #ifdef SUPPORT_I18N
2311 uschar * errstr = NULL;
2312
2313 /* If we must downconvert, do the from-address here. Remember we had to
2314 for the to-addresses (done below), and also (ugly) for re-doing when building
2315 the delivery log line. */
2316
2317 if ( addrlist->prop.utf8_msg
2318 && (addrlist->prop.utf8_downcvt || !(peer_offered & PEER_OFFERED_UTF8))
2319 )
2320 {
2321 if (s = string_address_utf8_to_alabel(return_path, &errstr), errstr)
2322 {
2323 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE);
2324 yield = ERROR;
2325 goto SEND_QUIT;
2326 }
2327 setflag(addrlist, af_utf8_downcvt);
2328 }
2329 #endif
2330
2331 rc = smtp_write_command(&outblock, pipelining_active,
2332 "MAIL FROM:<%s>%s\r\n", s, buffer);
2333 }
2334
2335 mail_command = string_copy(big_buffer); /* Save for later error message */
2336
2337 switch(rc)
2338 {
2339 case -1: /* Transmission error */
2340 goto SEND_FAILED;
2341
2342 case +1: /* Block was sent */
2343 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2344 ob->command_timeout))
2345 {
2346 if (errno == 0 && buffer[0] == '4')
2347 {
2348 errno = ERRNO_MAIL4XX;
2349 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2350 }
2351 goto RESPONSE_FAILED;
2352 }
2353 lflags.pending_MAIL = FALSE;
2354 break;
2355 }
2356
2357 /* Pass over all the relevant recipient addresses for this host, which are the
2358 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
2359 several before we have to read the responses for those seen so far. This
2360 checking is done by a subroutine because it also needs to be done at the end.
2361 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
2362 the next one if not all are sent.
2363
2364 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
2365 last address because we want to abort if any recipients have any kind of
2366 problem, temporary or permanent. We know that all recipient addresses will have
2367 the PENDING_DEFER status, because only one attempt is ever made, and we know
2368 that max_rcpt will be large, so all addresses will be done at once. */
2369
2370 for (addr = first_addr;
2371 addr && address_count < max_rcpt;
2372 addr = addr->next)
2373 if (addr->transport_return == PENDING_DEFER)
2374 {
2375 int count;
2376 BOOL no_flush;
2377 uschar * rcpt_addr;
2378
2379 addr->dsn_aware = peer_offered & PEER_OFFERED_DSN
2380 ? dsn_support_yes : dsn_support_no;
2381
2382 address_count++;
2383 no_flush = pipelining_active && (!mua_wrapper || addr->next);
2384
2385 /* Add any DSN flags to the rcpt command and add to the sent string */
2386
2387 p = buffer;
2388 *p = 0;
2389
2390 if (peer_offered & PEER_OFFERED_DSN && !(addr->dsn_flags & rf_dsnlasthop))
2391 {
2392 if (addr->dsn_flags & rf_dsnflags)
2393 {
2394 int i;
2395 BOOL first = TRUE;
2396 Ustrcpy(p, " NOTIFY=");
2397 while (*p) p++;
2398 for (i = 0; i < 4; i++)
2399 if ((addr->dsn_flags & rf_list[i]) != 0)
2400 {
2401 if (!first) *p++ = ',';
2402 first = FALSE;
2403 Ustrcpy(p, rf_names[i]);
2404 while (*p) p++;
2405 }
2406 }
2407
2408 if (addr->dsn_orcpt)
2409 {
2410 string_format(p, sizeof(buffer) - (p-buffer), " ORCPT=%s",
2411 addr->dsn_orcpt);
2412 while (*p) p++;
2413 }
2414 }
2415
2416 /* Now send the RCPT command, and process outstanding responses when
2417 necessary. After a timeout on RCPT, we just end the function, leaving the
2418 yield as OK, because this error can often mean that there is a problem with
2419 just one address, so we don't want to delay the host. */
2420
2421 rcpt_addr = transport_rcpt_address(addr, tblock->rcpt_include_affixes);
2422
2423 #ifdef SUPPORT_I18N
2424 {
2425 uschar * dummy_errstr;
2426 if ( testflag(addrlist, af_utf8_downcvt)
2427 && (rcpt_addr = string_address_utf8_to_alabel(rcpt_addr, &dummy_errstr),
2428 dummy_errstr
2429 ) )
2430 {
2431 errno = ERRNO_EXPANDFAIL;
2432 goto SEND_FAILED;
2433 }
2434 }
2435 #endif
2436
2437 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s%s\r\n",
2438 rcpt_addr, igquotstr, buffer);
2439
2440 if (count < 0) goto SEND_FAILED;
2441 if (count > 0)
2442 {
2443 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
2444 &sync_addr, host, count, ob->address_retry_include_sender,
2445 lflags.pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
2446 sizeof(buffer)))
2447 {
2448 case 3: lflags.ok = TRUE; /* 2xx & 5xx => OK & progress made */
2449 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2450 break;
2451
2452 case 1: lflags.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2453 if (!lflags.lmtp) completed_address = TRUE; /* can't tell about progress yet */
2454 case 0: /* No 2xx or 5xx, but no probs */
2455 break;
2456
2457 case -1: goto END_OFF; /* Timeout on RCPT */
2458 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
2459 }
2460 lflags.pending_MAIL = FALSE; /* Dealt with MAIL */
2461 }
2462 } /* Loop for next address */
2463
2464 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
2465 permanently or temporarily. We should have flushed and synced after the last
2466 RCPT. */
2467
2468 if (mua_wrapper)
2469 {
2470 address_item *badaddr;
2471 for (badaddr = first_addr; badaddr; badaddr = badaddr->next)
2472 if (badaddr->transport_return != PENDING_OK)
2473 {
2474 /*XXX could we find a better errno than 0 here? */
2475 set_errno_nohost(addrlist, 0, badaddr->message, FAIL,
2476 testflag(badaddr, af_pass_message));
2477 lflags.ok = FALSE;
2478 break;
2479 }
2480 }
2481
2482 /* If ok is TRUE, we know we have got at least one good recipient, and must now
2483 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
2484 have a good recipient buffered up if we are pipelining. We don't want to waste
2485 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
2486 are pipelining. The responses are all handled by sync_responses().
2487 If using CHUNKING, do not send a BDAT until we know how big a chunk we want
2488 to send is. */
2489
2490 if ( !(peer_offered & PEER_OFFERED_CHUNKING)
2491 && (lflags.ok || (pipelining_active && !mua_wrapper)))
2492 {
2493 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
2494
2495 if (count < 0) goto SEND_FAILED;
2496 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
2497 host, count, ob->address_retry_include_sender, lflags.pending_MAIL,
2498 lflags.ok ? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
2499 {
2500 case 3: lflags.ok = TRUE; /* 2xx & 5xx => OK & progress made */
2501 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2502 break;
2503
2504 case 1: lflags.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2505 if (!lflags.lmtp) completed_address = TRUE; /* can't tell about progress yet */
2506 case 0: break; /* No 2xx or 5xx, but no probs */
2507
2508 case -1: goto END_OFF; /* Timeout on RCPT */
2509 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2510 }
2511 pipelining_active = FALSE;
2512 }
2513
2514 /* If there were no good recipients (but otherwise there have been no
2515 problems), just set ok TRUE, since we have handled address-specific errors
2516 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
2517 for handling the SMTP dot-handling protocol, flagging to apply to headers as
2518 well as body. Set the appropriate timeout value to be used for each chunk.
2519 (Haven't been able to make it work using select() for writing yet.) */
2520
2521 if (!(peer_offered & PEER_OFFERED_CHUNKING) && !lflags.ok)
2522 {
2523 /* Save the first address of the next batch. */
2524 first_addr = addr;
2525
2526 lflags.ok = TRUE;
2527 }
2528 else
2529 {
2530 transport_ctx tctx = {
2531 tblock,
2532 addrlist,
2533 US".", US"..", /* Escaping strings */
2534 topt_use_crlf | topt_escape_headers
2535 | (tblock->body_only ? topt_no_headers : 0)
2536 | (tblock->headers_only ? topt_no_body : 0)
2537 | (tblock->return_path_add ? topt_add_return_path : 0)
2538 | (tblock->delivery_date_add ? topt_add_delivery_date : 0)
2539 | (tblock->envelope_to_add ? topt_add_envelope_to : 0)
2540 };
2541
2542 /* If using CHUNKING we need a callback from the generic transport
2543 support to us, for the sending of BDAT smtp commands and the reaping
2544 of responses. The callback needs a whole bunch of state so set up
2545 a transport-context structure to be passed around. */
2546
2547 if (peer_offered & PEER_OFFERED_CHUNKING)
2548 {
2549 tctx.check_string = tctx.escape_string = NULL;
2550 tctx.options |= topt_use_bdat;
2551 tctx.chunk_cb = smtp_chunk_cmd_callback;
2552 tctx.inblock = &inblock;
2553 tctx.outblock = &outblock;
2554 tctx.host = host;
2555 tctx.first_addr = first_addr;
2556 tctx.sync_addr = &sync_addr;
2557 tctx.pending_MAIL = lflags.pending_MAIL;
2558 tctx.pending_BDAT = FALSE;
2559 tctx.good_RCPT = lflags.ok;
2560 tctx.completed_address = &completed_address;
2561 tctx.cmd_count = 0;
2562 tctx.buffer = buffer;
2563 }
2564 else
2565 tctx.options |= topt_end_dot;
2566
2567 /* Save the first address of the next batch. */
2568 first_addr = addr;
2569
2570 /* Responses from CHUNKING commands go in buffer. Otherwise,
2571 there has not been a response. */
2572
2573 buffer[0] = 0;
2574
2575 sigalrm_seen = FALSE;
2576 transport_write_timeout = ob->data_timeout;
2577 smtp_command = US"sending data block"; /* For error messages */
2578 DEBUG(D_transport|D_v)
2579 if (peer_offered & PEER_OFFERED_CHUNKING)
2580 debug_printf(" will write message using CHUNKING\n");
2581 else
2582 debug_printf(" SMTP>> writing message and terminating \".\"\n");
2583 transport_count = 0;
2584
2585 #ifndef DISABLE_DKIM
2586 lflags.ok = dkim_transport_write_message(inblock.sock, &tctx, &ob->dkim);
2587 #else
2588 lflags.ok = transport_write_message(inblock.sock, &tctx, 0);
2589 #endif
2590
2591 /* transport_write_message() uses write() because it is called from other
2592 places to write to non-sockets. This means that under some OS (e.g. Solaris)
2593 it can exit with "Broken pipe" as its error. This really means that the
2594 socket got closed at the far end. */
2595
2596 transport_write_timeout = 0; /* for subsequent transports */
2597
2598 /* Failure can either be some kind of I/O disaster (including timeout),
2599 or the failure of a transport filter or the expansion of added headers.
2600 Or, when CHUNKING, it can be a protocol-detected failure. */
2601
2602 if (!lflags.ok)
2603 goto RESPONSE_FAILED;
2604
2605 /* We used to send the terminating "." explicitly here, but because of
2606 buffering effects at both ends of TCP/IP connections, you don't gain
2607 anything by keeping it separate, so it might as well go in the final
2608 data buffer for efficiency. This is now done by setting the topt_end_dot
2609 flag above. */
2610
2611 smtp_command = US"end of data";
2612
2613 if (peer_offered & PEER_OFFERED_CHUNKING && tctx.cmd_count > 1)
2614 {
2615 /* Reap any outstanding MAIL & RCPT commands, but not a DATA-go-ahead */
2616 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
2617 host, tctx.cmd_count-1, ob->address_retry_include_sender,
2618 lflags.pending_MAIL, 0,
2619 &inblock, ob->command_timeout, buffer, sizeof(buffer)))
2620 {
2621 case 3: lflags.ok = TRUE; /* 2xx & 5xx => OK & progress made */
2622 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2623 break;
2624
2625 case 1: lflags.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2626 if (!lflags.lmtp) completed_address = TRUE; /* can't tell about progress yet */
2627 case 0: break; /* No 2xx or 5xx, but no probs */
2628
2629 case -1: goto END_OFF; /* Timeout on RCPT */
2630 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2631 }
2632 }
2633
2634 #ifndef DISABLE_PRDR
2635 /* For PRDR we optionally get a partial-responses warning
2636 * followed by the individual responses, before going on with
2637 * the overall response. If we don't get the warning then deal
2638 * with per non-PRDR. */
2639 if(lflags.prdr_active)
2640 {
2641 lflags.ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '3',
2642 ob->final_timeout);
2643 if (!lflags.ok && errno == 0) switch(buffer[0])
2644 {
2645 case '2': lflags.prdr_active = FALSE;
2646 lflags.ok = TRUE;
2647 break;
2648 case '4': errno = ERRNO_DATA4XX;
2649 addrlist->more_errno |=
2650 ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2651 break;
2652 }
2653 }
2654 else
2655 #endif
2656
2657 /* For non-PRDR SMTP, we now read a single response that applies to the
2658 whole message. If it is OK, then all the addresses have been delivered. */
2659
2660 if (!lflags.lmtp)
2661 {
2662 lflags.ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2663 ob->final_timeout);
2664 if (!lflags.ok && errno == 0 && buffer[0] == '4')
2665 {
2666 errno = ERRNO_DATA4XX;
2667 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2668 }
2669 }
2670
2671 /* For LMTP, we get back a response for every RCPT command that we sent;
2672 some may be accepted and some rejected. For those that get a response, their
2673 status is fixed; any that are accepted have been handed over, even if later
2674 responses crash - at least, that's how I read RFC 2033.
2675
2676 If all went well, mark the recipient addresses as completed, record which
2677 host/IPaddress they were delivered to, and cut out RSET when sending another
2678 message down the same channel. Write the completed addresses to the journal
2679 now so that they are recorded in case there is a crash of hardware or
2680 software before the spool gets updated. Also record the final SMTP
2681 confirmation if needed (for SMTP only). */
2682
2683 if (lflags.ok)
2684 {
2685 int flag = '=';
2686 int delivery_time = (int)(time(NULL) - start_delivery_time);
2687 int len;
2688 uschar *conf = NULL;
2689
2690 lflags.send_rset = FALSE;
2691 pipelining_active = FALSE;
2692
2693 /* Set up confirmation if needed - applies only to SMTP */
2694
2695 if (
2696 #ifdef DISABLE_EVENT
2697 LOGGING(smtp_confirmation) &&
2698 #endif
2699 !lflags.lmtp
2700 )
2701 {
2702 const uschar *s = string_printing(buffer);
2703 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
2704 conf = (s == buffer)? (uschar *)string_copy(s) : US s;
2705 }
2706
2707 /* Process all transported addresses - for LMTP or PRDR, read a status for
2708 each one. */
2709
2710 for (addr = addrlist; addr != first_addr; addr = addr->next)
2711 {
2712 if (addr->transport_return != PENDING_OK) continue;
2713
2714 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
2715 remaining addresses. Otherwise, it's a return code for just the one
2716 address. For temporary errors, add a retry item for the address so that
2717 it doesn't get tried again too soon. */
2718
2719 #ifndef DISABLE_PRDR
2720 if (lflags.lmtp || lflags.prdr_active)
2721 #else
2722 if (lflags.lmtp)
2723 #endif
2724 {
2725 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2726 ob->final_timeout))
2727 {
2728 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
2729 addr->message = string_sprintf(
2730 #ifndef DISABLE_PRDR
2731 "%s error after %s: %s", lflags.prdr_active ? "PRDR":"LMTP",
2732 #else
2733 "LMTP error after %s: %s",
2734 #endif
2735 big_buffer, string_printing(buffer));
2736 setflag(addr, af_pass_message); /* Allow message to go to user */
2737 if (buffer[0] == '5')
2738 addr->transport_return = FAIL;
2739 else
2740 {
2741 errno = ERRNO_DATA4XX;
2742 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2743 addr->transport_return = DEFER;
2744 #ifndef DISABLE_PRDR
2745 if (!lflags.prdr_active)
2746 #endif
2747 retry_add_item(addr, addr->address_retry_key, 0);
2748 }
2749 continue;
2750 }
2751 completed_address = TRUE; /* NOW we can set this flag */
2752 if (LOGGING(smtp_confirmation))
2753 {
2754 const uschar *s = string_printing(buffer);
2755 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
2756 conf = (s == buffer)? (uschar *)string_copy(s) : US s;
2757 }
2758 }
2759
2760 /* SMTP, or success return from LMTP for this address. Pass back the
2761 actual host that was used. */
2762
2763 addr->transport_return = OK;
2764 addr->more_errno = delivery_time;
2765 addr->host_used = host;
2766 addr->special_action = flag;
2767 addr->message = conf;
2768 #ifndef DISABLE_PRDR
2769 if (lflags.prdr_active) addr->flags |= af_prdr_used;
2770 #endif
2771 if (peer_offered & PEER_OFFERED_CHUNKING) addr->flags |= af_chunking_used;
2772 flag = '-';
2773
2774 #ifndef DISABLE_PRDR
2775 if (!lflags.prdr_active)
2776 #endif
2777 {
2778 /* Update the journal. For homonymic addresses, use the base address plus
2779 the transport name. See lots of comments in deliver.c about the reasons
2780 for the complications when homonyms are involved. Just carry on after
2781 write error, as it may prove possible to update the spool file later. */
2782
2783 if (testflag(addr, af_homonym))
2784 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2785 else
2786 sprintf(CS buffer, "%.500s\n", addr->unique);
2787
2788 DEBUG(D_deliver) debug_printf("journalling %s\n", buffer);
2789 len = Ustrlen(CS buffer);
2790 if (write(journal_fd, buffer, len) != len)
2791 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2792 "%s: %s", buffer, strerror(errno));
2793 }
2794 }
2795
2796 #ifndef DISABLE_PRDR
2797 if (lflags.prdr_active)
2798 {
2799 /* PRDR - get the final, overall response. For any non-success
2800 upgrade all the address statuses. */
2801 lflags.ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2802 ob->final_timeout);
2803 if (!lflags.ok)
2804 {
2805 if(errno == 0 && buffer[0] == '4')
2806 {
2807 errno = ERRNO_DATA4XX;
2808 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2809 }
2810 for (addr = addrlist; addr != first_addr; addr = addr->next)
2811 if (buffer[0] == '5' || addr->transport_return == OK)
2812 addr->transport_return = PENDING_OK; /* allow set_errno action */
2813 goto RESPONSE_FAILED;
2814 }
2815
2816 /* Update the journal, or setup retry. */
2817 for (addr = addrlist; addr != first_addr; addr = addr->next)
2818 if (addr->transport_return == OK)
2819 {
2820 if (testflag(addr, af_homonym))
2821 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2822 else
2823 sprintf(CS buffer, "%.500s\n", addr->unique);
2824
2825 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s\n", buffer);
2826 len = Ustrlen(CS buffer);
2827 if (write(journal_fd, buffer, len) != len)
2828 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2829 "%s: %s", buffer, strerror(errno));
2830 }
2831 else if (addr->transport_return == DEFER)
2832 retry_add_item(addr, addr->address_retry_key, -2);
2833 }
2834 #endif
2835
2836 /* Ensure the journal file is pushed out to disk. */
2837
2838 if (EXIMfsync(journal_fd) < 0)
2839 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
2840 strerror(errno));
2841 }
2842 }
2843
2844
2845 /* Handle general (not specific to one address) failures here. The value of ok
2846 is used to skip over this code on the falling through case. A timeout causes a
2847 deferral. Other errors may defer or fail according to the response code, and
2848 may set up a special errno value, e.g. after connection chopped, which is
2849 assumed if errno == 0 and there is no text in the buffer. If control reaches
2850 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
2851 the problem is not related to this specific message. */
2852
2853 if (!lflags.ok)
2854 {
2855 int code, set_rc;
2856 uschar * set_message;
2857
2858 RESPONSE_FAILED:
2859 {
2860 save_errno = errno;
2861 message = NULL;
2862 lflags.send_quit = check_response(host, &save_errno, addrlist->more_errno,
2863 buffer, &code, &message, &pass_message);
2864 goto FAILED;
2865 }
2866
2867 SEND_FAILED:
2868 {
2869 save_errno = errno;
2870 code = '4';
2871 message = US string_sprintf("send() to %s [%s] failed: %s",
2872 host->name, host->address, strerror(save_errno));
2873 lflags.send_quit = FALSE;
2874 goto FAILED;
2875 }
2876
2877 /* This label is jumped to directly when a TLS negotiation has failed,
2878 or was not done for a host for which it is required. Values will be set
2879 in message and save_errno, and setting_up will always be true. Treat as
2880 a temporary error. */
2881
2882 #ifdef SUPPORT_TLS
2883 TLS_FAILED:
2884 code = '4';
2885 #endif
2886
2887 /* If the failure happened while setting up the call, see if the failure was
2888 a 5xx response (this will either be on connection, or following HELO - a 5xx
2889 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
2890 never going to accept them. For other errors during setting up (timeouts or
2891 whatever), defer all addresses, and yield DEFER, so that the host is not
2892 tried again for a while. */
2893
2894 FAILED:
2895 lflags.ok = FALSE; /* For when reached by GOTO */
2896 set_message = message;
2897
2898 if (lflags.setting_up)
2899 if (code == '5')
2900 set_rc = FAIL;
2901 else
2902 yield = set_rc = DEFER;
2903
2904 /* We want to handle timeouts after MAIL or "." and loss of connection after
2905 "." specially. They can indicate a problem with the sender address or with
2906 the contents of the message rather than a real error on the connection. These
2907 cases are treated in the same way as a 4xx response. This next bit of code
2908 does the classification. */
2909
2910 else
2911 {
2912 BOOL message_error;
2913
2914 switch(save_errno)
2915 {
2916 #ifdef SUPPORT_I18N
2917 case ERRNO_UTF8_FWD:
2918 code = '5';
2919 /*FALLTHROUGH*/
2920 #endif
2921 case 0:
2922 case ERRNO_MAIL4XX:
2923 case ERRNO_DATA4XX:
2924 message_error = TRUE;
2925 break;
2926
2927 case ETIMEDOUT:
2928 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
2929 Ustrncmp(smtp_command,"end ",4) == 0;
2930 break;
2931
2932 case ERRNO_SMTPCLOSED:
2933 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
2934 break;
2935
2936 default:
2937 message_error = FALSE;
2938 break;
2939 }
2940
2941 /* Handle the cases that are treated as message errors. These are:
2942
2943 (a) negative response or timeout after MAIL
2944 (b) negative response after DATA
2945 (c) negative response or timeout or dropped connection after "."
2946 (d) utf8 support required and not offered
2947
2948 It won't be a negative response or timeout after RCPT, as that is dealt
2949 with separately above. The action in all cases is to set an appropriate
2950 error code for all the addresses, but to leave yield set to OK because the
2951 host itself has not failed. Of course, it might in practice have failed
2952 when we've had a timeout, but if so, we'll discover that at the next
2953 delivery attempt. For a temporary error, set the message_defer flag, and
2954 write to the logs for information if this is not the last host. The error
2955 for the last host will be logged as part of the address's log line. */
2956
2957 if (message_error)
2958 {
2959 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
2960
2961 /* If there's an errno, the message contains just the identity of
2962 the host. */
2963
2964 if (code == '5')
2965 set_rc = FAIL;
2966 else /* Anything other than 5 is treated as temporary */
2967 {
2968 set_rc = DEFER;
2969 if (save_errno > 0)
2970 message = US string_sprintf("%s: %s", message, strerror(save_errno));
2971 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
2972 msglog_line(host, message);
2973 *message_defer = TRUE;
2974 }
2975 }
2976
2977 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
2978 ".", or some other transportation error. We defer all addresses and yield
2979 DEFER, except for the case of failed add_headers expansion, or a transport
2980 filter failure, when the yield should be ERROR, to stop it trying other
2981 hosts. */
2982
2983 else
2984 {
2985 set_rc = DEFER;
2986 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
2987 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
2988 }
2989 }
2990
2991 set_errno(addrlist, save_errno, set_message, set_rc, pass_message, host
2992 #ifdef EXPERIMENTAL_DSN_INFO
2993 , smtp_greeting, helo_response
2994 #endif
2995 );
2996 }
2997
2998
2999 /* If all has gone well, send_quit will be set TRUE, implying we can end the
3000 SMTP session tidily. However, if there were too many addresses to send in one
3001 message (indicated by first_addr being non-NULL) we want to carry on with the
3002 rest of them. Also, it is desirable to send more than one message down the SMTP
3003 connection if there are several waiting, provided we haven't already sent so
3004 many as to hit the configured limit. The function transport_check_waiting looks
3005 for a waiting message and returns its id. Then transport_pass_socket tries to
3006 set up a continued delivery by passing the socket on to another process. The
3007 variable send_rset is FALSE if a message has just been successfully transfered.
3008
3009 If we are already sending down a continued channel, there may be further
3010 addresses not yet delivered that are aimed at the same host, but which have not
3011 been passed in this run of the transport. In this case, continue_more will be
3012 true, and all we should do is send RSET if necessary, and return, leaving the
3013 channel open.
3014
3015 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
3016 do not want to continue with other messages down the same channel, because that
3017 can lead to looping between two or more messages, all with the same,
3018 temporarily failing address(es). [The retry information isn't updated yet, so
3019 new processes keep on trying.] We probably also don't want to try more of this
3020 message's addresses either.
3021
3022 If we have started a TLS session, we have to end it before passing the
3023 connection to a new process. However, not all servers can handle this (Exim
3024 can), so we do not pass such a connection on if the host matches
3025 hosts_nopass_tls. */
3026
3027 DEBUG(D_transport)
3028 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
3029 "yield=%d first_address is %sNULL\n", lflags.ok, lflags.send_quit,
3030 lflags.send_rset, continue_more, yield, first_addr ? "not " : "");
3031
3032 if (completed_address && lflags.ok && lflags.send_quit)
3033 {
3034 BOOL more;
3035 smtp_compare_t t_compare;
3036
3037 t_compare.tblock = tblock;
3038 t_compare.current_sender_address = sender_address;
3039
3040 if ( first_addr != NULL
3041 || continue_more
3042 || ( ( tls_out.active < 0
3043 || verify_check_given_host(&ob->hosts_nopass_tls, host) != OK
3044 )
3045 &&
3046 transport_check_waiting(tblock->name, host->name,
3047 tblock->connection_max_messages, new_message_id, &more,
3048 (oicf)smtp_are_same_identities, (void*)&t_compare)
3049 ) )
3050 {
3051 uschar *msg;
3052 BOOL pass_message;
3053
3054 if (lflags.send_rset)
3055 {
3056 if (! (lflags.ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
3057 {
3058 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
3059 host->address, strerror(save_errno));
3060 lflags.send_quit = FALSE;
3061 }
3062 else if (! (lflags.ok = smtp_read_response(&inblock, buffer,
3063 sizeof(buffer), '2', ob->command_timeout)))
3064 {
3065 int code;
3066 lflags.send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
3067 &pass_message);
3068 if (!lflags.send_quit)
3069 {
3070 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
3071 host->name, host->address, msg);
3072 }
3073 }
3074 }
3075
3076 /* Either RSET was not needed, or it succeeded */
3077
3078 if (lflags.ok)
3079 {
3080 if (first_addr != NULL) /* More addresses still to be sent */
3081 { /* in this run of the transport */
3082 continue_sequence++; /* Causes * in logging */
3083 goto SEND_MESSAGE;
3084 }
3085 if (continue_more) return yield; /* More addresses for another run */
3086
3087 /* Pass the socket to a new Exim process. Before doing so, we must shut
3088 down TLS. Not all MTAs allow for the continuation of the SMTP session
3089 when TLS is shut down. We test for this by sending a new EHLO. If we
3090 don't get a good response, we don't attempt to pass the socket on. */
3091
3092 #ifdef SUPPORT_TLS
3093 if (tls_out.active >= 0)
3094 {
3095 tls_close(FALSE, TRUE);
3096 smtp_peer_options = smtp_peer_options_wrap;
3097 if (lflags.smtps)
3098 lflags.ok = FALSE;
3099 else
3100 lflags.ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
3101 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
3102 ob->command_timeout);
3103 }
3104 #endif
3105
3106 /* If the socket is successfully passed, we musn't send QUIT (or
3107 indeed anything!) from here. */
3108
3109 /*XXX DSN_INFO: assume likely to do new HELO; but for greet we'll want to
3110 propagate it from the initial
3111 */
3112 if (lflags.ok && transport_pass_socket(tblock->name, host->name,
3113 host->address, new_message_id, inblock.sock))
3114 lflags.send_quit = FALSE;
3115 }
3116
3117 /* If RSET failed and there are addresses left, they get deferred. */
3118
3119 else set_errno(first_addr, errno, msg, DEFER, FALSE, host
3120 #ifdef EXPERIMENTAL_DSN_INFO
3121 , smtp_greeting, helo_response
3122 #endif
3123 );
3124 }
3125 }
3126
3127 /* End off tidily with QUIT unless the connection has died or the socket has
3128 been passed to another process. There has been discussion on the net about what
3129 to do after sending QUIT. The wording of the RFC suggests that it is necessary
3130 to wait for a response, but on the other hand, there isn't anything one can do
3131 with an error response, other than log it. Exim used to do that. However,
3132 further discussion suggested that it is positively advantageous not to wait for
3133 the response, but to close the session immediately. This is supposed to move
3134 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
3135 load from the server. (Hosts that are both servers and clients may not see much
3136 difference, of course.) Further discussion indicated that this was safe to do
3137 on Unix systems which have decent implementations of TCP/IP that leave the
3138 connection around for a while (TIME_WAIT) after the application has gone away.
3139 This enables the response sent by the server to be properly ACKed rather than
3140 timed out, as can happen on broken TCP/IP implementations on other OS.
3141
3142 This change is being made on 31-Jul-98. After over a year of trouble-free
3143 operation, the old commented-out code was removed on 17-Sep-99. */
3144
3145 SEND_QUIT:
3146 if (lflags.send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
3147
3148 END_OFF:
3149
3150 #ifdef SUPPORT_TLS
3151 tls_close(FALSE, TRUE);
3152 #endif
3153
3154 /* Close the socket, and return the appropriate value, first setting
3155 works because the NULL setting is passed back to the calling process, and
3156 remote_max_parallel is forced to 1 when delivering over an existing connection,
3157
3158 If all went well and continue_more is set, we shouldn't actually get here if
3159 there are further addresses, as the return above will be taken. However,
3160 writing RSET might have failed, or there may be other addresses whose hosts are
3161 specified in the transports, and therefore not visible at top level, in which
3162 case continue_more won't get set. */
3163
3164 HDEBUG(D_transport|D_acl|D_v) debug_printf(" SMTP(close)>>\n");
3165 if (lflags.send_quit)
3166 {
3167 shutdown(outblock.sock, SHUT_WR);
3168 for (rc = 16; read(inblock.sock, inbuffer, sizeof(inbuffer)) > 0 && rc > 0;)
3169 rc--; /* drain socket */
3170 }
3171 (void)close(inblock.sock);
3172
3173 #ifndef DISABLE_EVENT
3174 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
3175 #endif
3176
3177 continue_transport = NULL;
3178 continue_hostname = NULL;
3179 return yield;
3180 }
3181
3182
3183
3184
3185 /*************************************************
3186 * Closedown entry point *
3187 *************************************************/
3188
3189 /* This function is called when exim is passed an open smtp channel
3190 from another incarnation, but the message which it has been asked
3191 to deliver no longer exists. The channel is on stdin.
3192
3193 We might do fancy things like looking for another message to send down
3194 the channel, but if the one we sought has gone, it has probably been
3195 delivered by some other process that itself will seek further messages,
3196 so just close down our connection.
3197
3198 Argument: pointer to the transport instance block
3199 Returns: nothing
3200 */
3201
3202 void
3203 smtp_transport_closedown(transport_instance *tblock)
3204 {
3205 smtp_transport_options_block *ob =
3206 (smtp_transport_options_block *)(tblock->options_block);
3207 smtp_inblock inblock;
3208 smtp_outblock outblock;
3209 uschar buffer[256];
3210 uschar inbuffer[4096];
3211 uschar outbuffer[16];
3212
3213 inblock.sock = fileno(stdin);
3214 inblock.buffer = inbuffer;
3215 inblock.buffersize = sizeof(inbuffer);
3216 inblock.ptr = inbuffer;
3217 inblock.ptrend = inbuffer;
3218
3219 outblock.sock = inblock.sock;
3220 outblock.buffersize = sizeof(outbuffer);
3221 outblock.buffer = outbuffer;
3222 outblock.ptr = outbuffer;
3223 outblock.cmd_count = 0;
3224 outblock.authenticating = FALSE;
3225
3226 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
3227 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
3228 ob->command_timeout);
3229 (void)close(inblock.sock);
3230 }
3231
3232
3233
3234 /*************************************************
3235 * Prepare addresses for delivery *
3236 *************************************************/
3237
3238 /* This function is called to flush out error settings from previous delivery
3239 attempts to other hosts. It also records whether we got here via an MX record
3240 or not in the more_errno field of the address. We are interested only in
3241 addresses that are still marked DEFER - others may have got delivered to a
3242 previously considered IP address. Set their status to PENDING_DEFER to indicate
3243 which ones are relevant this time.
3244
3245 Arguments:
3246 addrlist the list of addresses
3247 host the host we are delivering to
3248
3249 Returns: the first address for this delivery
3250 */
3251
3252 static address_item *
3253 prepare_addresses(address_item *addrlist, host_item *host)
3254 {
3255 address_item *first_addr = NULL;
3256 address_item *addr;
3257 for (addr = addrlist; addr; addr = addr->next)
3258 if (addr->transport_return == DEFER)
3259 {
3260 if (!first_addr) first_addr = addr;
3261 addr->transport_return = PENDING_DEFER;
3262 addr->basic_errno = 0;
3263 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
3264 addr->message = NULL;
3265 #ifdef SUPPORT_TLS
3266 addr->cipher = NULL;
3267 addr->ourcert = NULL;
3268 addr->peercert = NULL;
3269 addr->peerdn = NULL;
3270 addr->ocsp = OCSP_NOT_REQ;
3271 #endif
3272 #ifdef EXPERIMENTAL_DSN_INFO
3273 addr->smtp_greeting = NULL;
3274 addr->helo_response = NULL;
3275 #endif
3276 }
3277 return first_addr;
3278 }
3279
3280
3281
3282 /*************************************************
3283 * Main entry point *
3284 *************************************************/
3285
3286 /* See local README for interface details. As this is a remote transport, it is
3287 given a chain of addresses to be delivered in one connection, if possible. It
3288 always returns TRUE, indicating that each address has its own independent
3289 status set, except if there is a setting up problem, in which case it returns
3290 FALSE. */
3291
3292 BOOL
3293 smtp_transport_entry(
3294 transport_instance *tblock, /* data for this instantiation */
3295 address_item *addrlist) /* addresses we are working on */
3296 {
3297 int cutoff_retry;
3298 int port;
3299 int hosts_defer = 0;
3300 int hosts_fail = 0;
3301 int hosts_looked_up = 0;
3302 int hosts_retry = 0;
3303 int hosts_serial = 0;
3304 int hosts_total = 0;
3305 int total_hosts_tried = 0;
3306 address_item *addr;
3307 BOOL expired = TRUE;
3308 uschar *expanded_hosts = NULL;
3309 uschar *pistring;
3310 uschar *tid = string_sprintf("%s transport", tblock->name);
3311 smtp_transport_options_block *ob =
3312 (smtp_transport_options_block *)(tblock->options_block);
3313 host_item *hostlist = addrlist->host_list;
3314 host_item *host = NULL;
3315
3316 DEBUG(D_transport)
3317 {
3318 debug_printf("%s transport entered\n", tblock->name);
3319 for (addr = addrlist; addr; addr = addr->next)
3320 debug_printf(" %s\n", addr->address);
3321 if (hostlist)
3322 {
3323 debug_printf("hostlist:\n");
3324 for (host = hostlist; host; host = host->next)
3325 debug_printf(" %s:%d\n", host->name, host->port);
3326 }
3327 if (continue_hostname) debug_printf("already connected to %s [%s]\n",
3328 continue_hostname, continue_host_address);
3329 }
3330
3331 /* Set the flag requesting that these hosts be added to the waiting
3332 database if the delivery fails temporarily or if we are running with
3333 queue_smtp or a 2-stage queue run. This gets unset for certain
3334 kinds of error, typically those that are specific to the message. */
3335
3336 update_waiting = TRUE;
3337
3338 /* If a host list is not defined for the addresses - they must all have the
3339 same one in order to be passed to a single transport - or if the transport has
3340 a host list with hosts_override set, use the host list supplied with the
3341 transport. It is an error for this not to exist. */
3342
3343 if (!hostlist || (ob->hosts_override && ob->hosts))
3344 {
3345 if (!ob->hosts)
3346 {
3347 addrlist->message = string_sprintf("%s transport called with no hosts set",
3348 tblock->name);
3349 addrlist->transport_return = PANIC;
3350 return FALSE; /* Only top address has status */
3351 }
3352
3353 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
3354 ob->hosts);
3355
3356 /* If the transport's host list contains no '$' characters, and we are not
3357 randomizing, it is fixed and therefore a chain of hosts can be built once
3358 and for all, and remembered for subsequent use by other calls to this
3359 transport. If, on the other hand, the host list does contain '$', or we are
3360 randomizing its order, we have to rebuild it each time. In the fixed case,
3361 as the hosts string will never be used again, it doesn't matter that we
3362 replace all the : characters with zeros. */
3363
3364 if (!ob->hostlist)
3365 {
3366 uschar *s = ob->hosts;
3367
3368 if (Ustrchr(s, '$') != NULL)
3369 {
3370 if (!(expanded_hosts = expand_string(s)))
3371 {
3372 addrlist->message = string_sprintf("failed to expand list of hosts "
3373 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
3374 addrlist->transport_return = search_find_defer ? DEFER : PANIC;
3375 return FALSE; /* Only top address has status */
3376 }
3377 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
3378 "\"%s\"\n", s, expanded_hosts);
3379 s = expanded_hosts;
3380 }
3381 else
3382 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
3383
3384 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
3385
3386 /* Check that the expansion yielded something useful. */
3387 if (!hostlist)
3388 {
3389 addrlist->message =
3390 string_sprintf("%s transport has empty hosts setting", tblock->name);
3391 addrlist->transport_return = PANIC;
3392 return FALSE; /* Only top address has status */
3393 }
3394
3395 /* If there was no expansion of hosts, save the host list for
3396 next time. */
3397
3398 if (!expanded_hosts) ob->hostlist = hostlist;
3399 }
3400
3401 /* This is not the first time this transport has been run in this delivery;
3402 the host list was built previously. */
3403
3404 else
3405 hostlist = ob->hostlist;
3406 }
3407
3408 /* The host list was supplied with the address. If hosts_randomize is set, we
3409 must sort it into a random order if it did not come from MX records and has not
3410 already been randomized (but don't bother if continuing down an existing
3411 connection). */
3412
3413 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continue_hostname)
3414 {
3415 host_item *newlist = NULL;
3416 while (hostlist)
3417 {
3418 host_item *h = hostlist;
3419 hostlist = hostlist->next;
3420
3421 h->sort_key = random_number(100);
3422
3423 if (!newlist)
3424 {
3425 h->next = NULL;
3426 newlist = h;
3427 }
3428 else if (h->sort_key < newlist->sort_key)
3429 {
3430 h->next = newlist;
3431 newlist = h;
3432 }
3433 else
3434 {
3435 host_item *hh = newlist;
3436 while (hh->next)
3437 {
3438 if (h->sort_key < hh->next->sort_key) break;
3439 hh = hh->next;
3440 }
3441 h->next = hh->next;
3442 hh->next = h;
3443 }
3444 }
3445
3446 hostlist = addrlist->host_list = newlist;
3447 }
3448
3449 /* Sort out the default port. */
3450
3451 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
3452
3453 /* For each host-plus-IP-address on the list:
3454
3455 . If this is a continued delivery and the host isn't the one with the
3456 current connection, skip.
3457
3458 . If the status is unusable (i.e. previously failed or retry checked), skip.
3459
3460 . If no IP address set, get the address, either by turning the name into
3461 an address, calling gethostbyname if gethostbyname is on, or by calling
3462 the DNS. The DNS may yield multiple addresses, in which case insert the
3463 extra ones into the list.
3464
3465 . Get the retry data if not previously obtained for this address and set the
3466 field which remembers the state of this address. Skip if the retry time is
3467 not reached. If not, remember whether retry data was found. The retry string
3468 contains both the name and the IP address.
3469
3470 . Scan the list of addresses and mark those whose status is DEFER as
3471 PENDING_DEFER. These are the only ones that will be processed in this cycle
3472 of the hosts loop.
3473
3474 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
3475 Some addresses may be successfully delivered, others may fail, and yet
3476 others may get temporary errors and so get marked DEFER.
3477
3478 . The return from the delivery attempt is OK if a connection was made and a
3479 valid SMTP dialogue was completed. Otherwise it is DEFER.
3480
3481 . If OK, add a "remove" retry item for this host/IPaddress, if any.
3482
3483 . If fail to connect, or other defer state, add a retry item.
3484
3485 . If there are any addresses whose status is still DEFER, carry on to the
3486 next host/IPaddress, unless we have tried the number of hosts given
3487 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
3488 there is some fancy logic for hosts_max_try that means its limit can be
3489 overstepped in some circumstances.
3490
3491 If we get to the end of the list, all hosts have deferred at least one address,
3492 or not reached their retry times. If delay_after_cutoff is unset, it requests a
3493 delivery attempt to those hosts whose last try was before the arrival time of
3494 the current message. To cope with this, we have to go round the loop a second
3495 time. After that, set the status and error data for any addresses that haven't
3496 had it set already. */
3497
3498 for (cutoff_retry = 0;
3499 expired && cutoff_retry < (ob->delay_after_cutoff ? 1 : 2);
3500 cutoff_retry++)
3501 {
3502 host_item *nexthost = NULL;
3503 int unexpired_hosts_tried = 0;
3504
3505 for (host = hostlist;
3506 host
3507 && unexpired_hosts_tried < ob->hosts_max_try
3508 && total_hosts_tried < ob->hosts_max_try_hardlimit;
3509 host = nexthost)
3510 {
3511 int rc;
3512 int host_af;
3513 uschar *rs;
3514 BOOL host_is_expired = FALSE;
3515 BOOL message_defer = FALSE;
3516 BOOL some_deferred = FALSE;
3517 address_item *first_addr = NULL;
3518 uschar *interface = NULL;
3519 uschar *retry_host_key = NULL;
3520 uschar *retry_message_key = NULL;
3521 uschar *serialize_key = NULL;
3522
3523 /* Default next host is next host. :-) But this can vary if the
3524 hosts_max_try limit is hit (see below). It may also be reset if a host
3525 address is looked up here (in case the host was multihomed). */
3526
3527 nexthost = host->next;
3528
3529 /* If the address hasn't yet been obtained from the host name, look it up
3530 now, unless the host is already marked as unusable. If it is marked as
3531 unusable, it means that the router was unable to find its IP address (in
3532 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
3533 the lookup failed last time. We don't get this far if *all* MX records
3534 point to non-existent hosts; that is treated as a hard error.
3535
3536 We can just skip this host entirely. When the hosts came from the router,
3537 the address will timeout based on the other host(s); when the address is
3538 looked up below, there is an explicit retry record added.
3539
3540 Note that we mustn't skip unusable hosts if the address is not unset; they
3541 may be needed as expired hosts on the 2nd time round the cutoff loop. */
3542
3543 if (!host->address)
3544 {
3545 int new_port, flags;
3546 host_item *hh;
3547
3548 if (host->status >= hstatus_unusable)
3549 {
3550 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
3551 host->name);
3552 continue;
3553 }
3554
3555 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
3556
3557 /* The host name is permitted to have an attached port. Find it, and
3558 strip it from the name. Just remember it for now. */
3559
3560 new_port = host_item_get_port(host);
3561
3562 /* Count hosts looked up */
3563
3564 hosts_looked_up++;
3565
3566 /* Find by name if so configured, or if it's an IP address. We don't
3567 just copy the IP address, because we need the test-for-local to happen. */
3568
3569 flags = HOST_FIND_BY_A;
3570 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
3571 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
3572
3573 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
3574 rc = host_find_byname(host, NULL, flags, NULL, TRUE);
3575 else
3576 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
3577 &ob->dnssec, /* domains for request/require */
3578 NULL, NULL);
3579
3580 /* Update the host (and any additional blocks, resulting from
3581 multihoming) with a host-specific port, if any. */
3582
3583 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
3584
3585 /* Failure to find the host at this time (usually DNS temporary failure)
3586 is really a kind of routing failure rather than a transport failure.
3587 Therefore we add a retry item of the routing kind, not to stop us trying
3588 to look this name up here again, but to ensure the address gets timed
3589 out if the failures go on long enough. A complete failure at this point
3590 commonly points to a configuration error, but the best action is still
3591 to carry on for the next host. */
3592
3593 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
3594 {
3595 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
3596 expired = FALSE;
3597 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
3598 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
3599 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
3600 host->status = hstatus_unusable;
3601
3602 for (addr = addrlist; addr; addr = addr->next)
3603 {
3604 if (addr->transport_return != DEFER) continue;
3605 addr->basic_errno = ERRNO_UNKNOWNHOST;
3606 addr->message =
3607 string_sprintf("failed to lookup IP address for %s", host->name);
3608 }
3609 continue;
3610 }
3611
3612 /* If the host is actually the local host, we may have a problem, or
3613 there may be some cunning configuration going on. In the problem case,
3614 log things and give up. The default transport status is already DEFER. */
3615
3616 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
3617 {
3618 for (addr = addrlist; addr; addr = addr->next)
3619 {
3620 addr->basic_errno = 0;
3621 addr->message = string_sprintf("%s transport found host %s to be "
3622 "local", tblock->name, host->name);
3623 }
3624 goto END_TRANSPORT;
3625 }
3626 } /* End of block for IP address lookup */
3627
3628 /* If this is a continued delivery, we are interested only in the host
3629 which matches the name of the existing open channel. The check is put
3630 here after the local host lookup, in case the name gets expanded as a
3631 result of the lookup. Set expired FALSE, to save the outer loop executing
3632 twice. */
3633
3634 if ( continue_hostname
3635 && ( Ustrcmp(continue_hostname, host->name) != 0
3636 || Ustrcmp(continue_host_address, host->address) != 0
3637 ) )
3638 {
3639 expired = FALSE;
3640 continue; /* With next host */
3641 }
3642
3643 /* Reset the default next host in case a multihomed host whose addresses
3644 are not looked up till just above added to the host list. */
3645
3646 nexthost = host->next;
3647
3648 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
3649 domain is in queue_smtp_domains, we don't actually want to attempt any
3650 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
3651 there is a lookup defer in queue_smtp_domains, proceed as if the domain
3652 were not in it. We don't want to hold up all SMTP deliveries! Except when
3653 doing a two-stage queue run, don't do this if forcing. */
3654
3655 if ((!deliver_force || queue_2stage) && (queue_smtp ||
3656 match_isinlist(addrlist->domain,
3657 (const uschar **)&queue_smtp_domains, 0,
3658 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
3659 {
3660 expired = FALSE;
3661 for (addr = addrlist; addr; addr = addr->next)
3662 if (addr->transport_return == DEFER)
3663 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
3664 continue; /* With next host */
3665 }
3666
3667 /* Count hosts being considered - purely for an intelligent comment
3668 if none are usable. */
3669
3670 hosts_total++;
3671
3672 /* Set $host and $host address now in case they are needed for the
3673 interface expansion or the serialize_hosts check; they remain set if an
3674 actual delivery happens. */
3675
3676 deliver_host = host->name;
3677 deliver_host_address = host->address;
3678 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
3679 : host->dnssec == DS_NO ? US"no"
3680 : US"";
3681
3682 /* Set up a string for adding to the retry key if the port number is not
3683 the standard SMTP port. A host may have its own port setting that overrides
3684 the default. */
3685
3686 pistring = string_sprintf(":%d", host->port == PORT_NONE
3687 ? port : host->port);
3688 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
3689
3690 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
3691 string is set, even if constant (as different transports can have different
3692 constant settings), we must add it to the key that is used for retries,
3693 because connections to the same host from a different interface should be
3694 treated separately. */
3695
3696 host_af = Ustrchr(host->address, ':') == NULL ? AF_INET : AF_INET6;
3697 if ((rs = ob->interface) && *rs)
3698 {
3699 if (!smtp_get_interface(rs, host_af, addrlist, &interface, tid))
3700 return FALSE;
3701 pistring = string_sprintf("%s/%s", pistring, interface);
3702 }
3703
3704 /* The first time round the outer loop, check the status of the host by
3705 inspecting the retry data. The second time round, we are interested only
3706 in expired hosts that haven't been tried since this message arrived. */
3707
3708 if (cutoff_retry == 0)
3709 {
3710 BOOL incl_ip;
3711 /* Ensure the status of the address is set by checking retry data if
3712 necessary. There may be host-specific retry data (applicable to all
3713 messages) and also data for retries of a specific message at this host.
3714 If either of these retry records are actually read, the keys used are
3715 returned to save recomputing them later. */
3716
3717 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3718 US"retry_include_ip_address", ob->retry_include_ip_address,
3719 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3720 continue; /* with next host */
3721
3722 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
3723 incl_ip, &retry_host_key, &retry_message_key);
3724
3725 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
3726 (host->address == NULL)? US"" : host->address, pistring,
3727 (host->status == hstatus_usable)? "usable" :
3728 (host->status == hstatus_unusable)? "unusable" :
3729 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
3730
3731 /* Skip this address if not usable at this time, noting if it wasn't
3732 actually expired, both locally and in the address. */
3733
3734 switch (host->status)
3735 {
3736 case hstatus_unusable:
3737 expired = FALSE;
3738 setflag(addrlist, af_retry_skipped);
3739 /* Fall through */
3740
3741 case hstatus_unusable_expired:
3742 switch (host->why)
3743 {
3744 case hwhy_retry: hosts_retry++; break;
3745 case hwhy_failed: hosts_fail++; break;
3746 case hwhy_deferred: hosts_defer++; break;
3747 }
3748
3749 /* If there was a retry message key, implying that previously there
3750 was a message-specific defer, we don't want to update the list of
3751 messages waiting for these hosts. */
3752
3753 if (retry_message_key) update_waiting = FALSE;
3754 continue; /* With the next host or IP address */
3755 }
3756 }
3757
3758 /* Second time round the loop: if the address is set but expired, and
3759 the message is newer than the last try, let it through. */
3760
3761 else
3762 {
3763 if ( !host->address
3764 || host->status != hstatus_unusable_expired
3765 || host->last_try > received_time)
3766 continue;
3767 DEBUG(D_transport) debug_printf("trying expired host %s [%s]%s\n",
3768 host->name, host->address, pistring);
3769 host_is_expired = TRUE;
3770 }
3771
3772 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
3773 it remains TRUE only if all hosts are expired and none are actually tried.
3774 */
3775
3776 expired = FALSE;
3777
3778 /* If this host is listed as one to which access must be serialized,
3779 see if another Exim process has a connection to it, and if so, skip
3780 this host. If not, update the database to record our connection to it
3781 and remember this for later deletion. Do not do any of this if we are
3782 sending the message down a pre-existing connection. */
3783
3784 if ( !continue_hostname
3785 && verify_check_given_host(&ob->serialize_hosts, host) == OK)
3786 {
3787 serialize_key = string_sprintf("host-serialize-%s", host->name);
3788 if (!enq_start(serialize_key, 1))
3789 {
3790 DEBUG(D_transport)
3791 debug_printf("skipping host %s because another Exim process "
3792 "is connected to it\n", host->name);
3793 hosts_serial++;
3794 continue;
3795 }
3796 }
3797
3798 /* OK, we have an IP address that is not waiting for its retry time to
3799 arrive (it might be expired) OR (second time round the loop) we have an
3800 expired host that hasn't been tried since the message arrived. Have a go
3801 at delivering the message to it. First prepare the addresses by flushing
3802 out the result of previous attempts, and finding the first address that
3803 is still to be delivered. */
3804
3805 first_addr = prepare_addresses(addrlist, host);
3806
3807 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
3808 message_id, host->name, host->address, addrlist->address,
3809 addrlist->next ? ", ..." : "");
3810
3811 set_process_info("delivering %s to %s [%s] (%s%s)",
3812 message_id, host->name, host->address, addrlist->address,
3813 addrlist->next ? ", ..." : "");
3814
3815 /* This is not for real; don't do the delivery. If there are
3816 any remaining hosts, list them. */
3817
3818 if (dont_deliver)
3819 {
3820 host_item *host2;
3821 set_errno_nohost(addrlist, 0, NULL, OK, FALSE);
3822 for (addr = addrlist; addr; addr = addr->next)
3823 {
3824 addr->host_used = host;
3825 addr->special_action = '*';
3826 addr->message = US"delivery bypassed by -N option";
3827 }
3828 DEBUG(D_transport)
3829 {
3830 debug_printf("*** delivery by %s transport bypassed by -N option\n"
3831 "*** host and remaining hosts:\n", tblock->name);
3832 for (host2 = host; host2; host2 = host2->next)
3833 debug_printf(" %s [%s]\n", host2->name,
3834 host2->address ? host2->address : US"unset");
3835 }
3836 rc = OK;
3837 }
3838
3839 /* This is for real. If the host is expired, we don't count it for
3840 hosts_max_retry. This ensures that all hosts must expire before an address
3841 is timed out, unless hosts_max_try_hardlimit (which protects against
3842 lunatic DNS configurations) is reached.
3843
3844 If the host is not expired and we are about to hit the hosts_max_retry
3845 limit, check to see if there is a subsequent hosts with a different MX
3846 value. If so, make that the next host, and don't count this one. This is a
3847 heuristic to make sure that different MXs do get tried. With a normal kind
3848 of retry rule, they would get tried anyway when the earlier hosts were
3849 delayed, but if the domain has a "retry every time" type of rule - as is
3850 often used for the the very large ISPs, that won't happen. */
3851
3852 else
3853 {
3854 host_item * thost;
3855 /* Make a copy of the host if it is local to this invocation
3856 of the transport. */
3857
3858 if (expanded_hosts)
3859 {
3860 thost = store_get(sizeof(host_item));
3861 *thost = *host;
3862 thost->name = string_copy(host->name);
3863 thost->address = string_copy(host->address);
3864 }
3865 else
3866 thost = host;
3867
3868 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
3869 {
3870 host_item *h;
3871 DEBUG(D_transport)
3872 debug_printf("hosts_max_try limit reached with this host\n");
3873 for (h = host; h; h = h->next) if (h->mx != host->mx)
3874 {
3875 nexthost = h;
3876 unexpired_hosts_tried--;
3877 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
3878 "and will be tried\n");
3879 break;
3880 }
3881 }
3882
3883 /* Attempt the delivery. */
3884
3885 total_hosts_tried++;
3886 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
3887 &message_defer, FALSE);
3888
3889 /* Yield is one of:
3890 OK => connection made, each address contains its result;
3891 message_defer is set for message-specific defers (when all
3892 recipients are marked defer)
3893 DEFER => there was a non-message-specific delivery problem;
3894 ERROR => there was a problem setting up the arguments for a filter,
3895 or there was a problem with expanding added headers
3896 */
3897
3898 /* If the result is not OK, there was a non-message-specific problem.
3899 If the result is DEFER, we need to write to the logs saying what happened
3900 for this particular host, except in the case of authentication and TLS
3901 failures, where the log has already been written. If all hosts defer a
3902 general message is written at the end. */
3903
3904 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL
3905 && first_addr->basic_errno != ERRNO_TLSFAILURE)
3906 write_logs(first_addr, host);
3907
3908 #ifndef DISABLE_EVENT
3909 if (rc == DEFER)
3910 deferred_event_raise(first_addr, host);
3911 #endif
3912
3913 /* If STARTTLS was accepted, but there was a failure in setting up the
3914 TLS session (usually a certificate screwup), and the host is not in
3915 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
3916 TLS forcibly turned off. We have to start from scratch with a new SMTP
3917 connection. That's why the retry is done from here, not from within
3918 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
3919 session, so the in-clear transmission after those errors, if permitted,
3920 happens inside smtp_deliver().] */
3921
3922 #ifdef SUPPORT_TLS
3923 if ( rc == DEFER
3924 && first_addr->basic_errno == ERRNO_TLSFAILURE
3925 && ob->tls_tempfail_tryclear
3926 && verify_check_given_host(&ob->hosts_require_tls, host) != OK
3927 )
3928 {
3929 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
3930 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
3931 first_addr = prepare_addresses(addrlist, host);
3932 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
3933 &message_defer, TRUE);
3934 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
3935 write_logs(first_addr, host);
3936 # ifndef DISABLE_EVENT
3937 if (rc == DEFER)
3938 deferred_event_raise(first_addr, host);
3939 # endif
3940 }
3941 #endif /*SUPPORT_TLS*/
3942 }
3943
3944 /* Delivery attempt finished */
3945
3946 rs = rc == OK ? US"OK"
3947 : rc == DEFER ? US"DEFER"
3948 : rc == ERROR ? US"ERROR"
3949 : US"?";
3950
3951 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
3952 message_id, host->name, host->address, addrlist->address,
3953 addrlist->next ? " (& others)" : "", rs);
3954
3955 /* Release serialization if set up */
3956
3957 if (serialize_key) enq_end(serialize_key);
3958
3959 /* If the result is DEFER, or if a host retry record is known to exist, we
3960 need to add an item to the retry chain for updating the retry database
3961 at the end of delivery. We only need to add the item to the top address,
3962 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
3963 for any other delivery attempts using the same address. (It is copied into
3964 the unusable tree at the outer level, so even if different address blocks
3965 contain the same address, it still won't get tried again.) */
3966
3967 if (rc == DEFER || retry_host_key)
3968 {
3969 int delete_flag = rc != DEFER ? rf_delete : 0;
3970 if (!retry_host_key)
3971 {
3972 BOOL incl_ip;
3973 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3974 US"retry_include_ip_address", ob->retry_include_ip_address,
3975 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3976 incl_ip = TRUE; /* error; use most-specific retry record */
3977
3978 retry_host_key = incl_ip
3979 ? string_sprintf("T:%S:%s%s", host->name, host->address, pistring)
3980 : string_sprintf("T:%S%s", host->name, pistring);
3981 }
3982
3983 /* If a delivery of another message over an existing SMTP connection
3984 yields DEFER, we do NOT set up retry data for the host. This covers the
3985 case when there are delays in routing the addresses in the second message
3986 that are so long that the server times out. This is alleviated by not
3987 routing addresses that previously had routing defers when handling an
3988 existing connection, but even so, this case may occur (e.g. if a
3989 previously happily routed address starts giving routing defers). If the
3990 host is genuinely down, another non-continued message delivery will
3991 notice it soon enough. */
3992
3993 if (delete_flag != 0 || !continue_hostname)
3994 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
3995
3996 /* We may have tried an expired host, if its retry time has come; ensure
3997 the status reflects the expiry for the benefit of any other addresses. */
3998
3999 if (rc == DEFER)
4000 {
4001 host->status = host_is_expired
4002 ? hstatus_unusable_expired : hstatus_unusable;
4003 host->why = hwhy_deferred;
4004 }
4005 }
4006
4007 /* If message_defer is set (host was OK, but every recipient got deferred
4008 because of some message-specific problem), or if that had happened
4009 previously so that a message retry key exists, add an appropriate item
4010 to the retry chain. Note that if there was a message defer but now there is
4011 a host defer, the message defer record gets deleted. That seems perfectly
4012 reasonable. Also, stop the message from being remembered as waiting
4013 for specific hosts. */
4014
4015 if (message_defer || retry_message_key)
4016 {
4017 int delete_flag = message_defer ? 0 : rf_delete;
4018 if (!retry_message_key)
4019 {
4020 BOOL incl_ip;
4021 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
4022 US"retry_include_ip_address", ob->retry_include_ip_address,
4023 ob->expand_retry_include_ip_address, &incl_ip) != OK)
4024 incl_ip = TRUE; /* error; use most-specific retry record */
4025
4026 retry_message_key = incl_ip
4027 ? string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
4028 message_id)
4029 : string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
4030 }
4031 retry_add_item(addrlist, retry_message_key,
4032 rf_message | rf_host | delete_flag);
4033 update_waiting = FALSE;
4034 }
4035
4036 /* Any return other than DEFER (that is, OK or ERROR) means that the
4037 addresses have got their final statuses filled in for this host. In the OK
4038 case, see if any of them are deferred. */
4039
4040 if (rc == OK)
4041 for (addr = addrlist; addr; addr = addr->next)
4042 if (addr->transport_return == DEFER)
4043 {
4044 some_deferred = TRUE;
4045 break;
4046 }
4047
4048 /* If no addresses deferred or the result was ERROR, return. We do this for
4049 ERROR because a failing filter set-up or add_headers expansion is likely to
4050 fail for any host we try. */
4051
4052 if (rc == ERROR || (rc == OK && !some_deferred))
4053 {
4054 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
4055 return TRUE; /* Each address has its status */
4056 }
4057
4058 /* If the result was DEFER or some individual addresses deferred, let
4059 the loop run to try other hosts with the deferred addresses, except for the
4060 case when we were trying to deliver down an existing channel and failed.
4061 Don't try any other hosts in this case. */
4062
4063 if (continue_hostname) break;
4064
4065 /* If the whole delivery, or some individual addresses, were deferred and
4066 there are more hosts that could be tried, do not count this host towards
4067 the hosts_max_try limit if the age of the message is greater than the
4068 maximum retry time for this host. This means we may try try all hosts,
4069 ignoring the limit, when messages have been around for some time. This is
4070 important because if we don't try all hosts, the address will never time
4071 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
4072
4073 if ((rc == DEFER || some_deferred) && nexthost)
4074 {
4075 BOOL timedout;
4076 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
4077
4078 if (retry && retry->rules)
4079 {
4080 retry_rule *last_rule;
4081 for (last_rule = retry->rules;
4082 last_rule->next;
4083 last_rule = last_rule->next);
4084 timedout = time(NULL) - received_time > last_rule->timeout;
4085 }
4086 else timedout = TRUE; /* No rule => timed out */
4087
4088 if (timedout)
4089 {
4090 unexpired_hosts_tried--;
4091 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
4092 "hosts_max_try (message older than host's retry time)\n");
4093 }
4094 }
4095 } /* End of loop for trying multiple hosts. */
4096
4097 /* This is the end of the loop that repeats iff expired is TRUE and
4098 ob->delay_after_cutoff is FALSE. The second time round we will
4099 try those hosts that haven't been tried since the message arrived. */
4100
4101 DEBUG(D_transport)
4102 {
4103 debug_printf("all IP addresses skipped or deferred at least one address\n");
4104 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
4105 debug_printf("retrying IP addresses not tried since message arrived\n");
4106 }
4107 }
4108
4109
4110 /* Get here if all IP addresses are skipped or defer at least one address. In
4111 MUA wrapper mode, this will happen only for connection or other non-message-
4112 specific failures. Force the delivery status for all addresses to FAIL. */
4113
4114 if (mua_wrapper)
4115 {
4116 for (addr = addrlist; addr; addr = addr->next)
4117 addr->transport_return = FAIL;
4118 goto END_TRANSPORT;
4119 }
4120
4121 /* In the normal, non-wrapper case, add a standard message to each deferred
4122 address if there hasn't been an error, that is, if it hasn't actually been
4123 tried this time. The variable "expired" will be FALSE if any deliveries were
4124 actually tried, or if there was at least one host that was not expired. That
4125 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
4126 a delivery has been tried, an error code will be set, and the failing of the
4127 message is handled by the retry code later.
4128
4129 If queue_smtp is set, or this transport was called to send a subsequent message
4130 down an existing TCP/IP connection, and something caused the host not to be
4131 found, we end up here, but can detect these cases and handle them specially. */
4132
4133 for (addr = addrlist; addr; addr = addr->next)
4134 {
4135 /* If host is not NULL, it means that we stopped processing the host list
4136 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
4137 means we need to behave as if some hosts were skipped because their retry
4138 time had not come. Specifically, this prevents the address from timing out.
4139 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
4140 hosts were tried. */
4141
4142 if (host)
4143 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
4144 {
4145 DEBUG(D_transport)
4146 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
4147 "hosts were tried\n");
4148 }
4149 else
4150 {
4151 DEBUG(D_transport)
4152 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
4153 setflag(addr, af_retry_skipped);
4154 }
4155
4156 if (queue_smtp) /* no deliveries attempted */
4157 {
4158 addr->transport_return = DEFER;
4159 addr->basic_errno = 0;
4160 addr->message = US"SMTP delivery explicitly queued";
4161 }
4162
4163 else if ( addr->transport_return == DEFER
4164 && (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0)
4165 && !addr->message
4166 )
4167 {
4168 addr->basic_errno = ERRNO_HRETRY;
4169 if (continue_hostname)
4170 addr->message = US"no host found for existing SMTP connection";
4171 else if (expired)
4172 {
4173 setflag(addr, af_pass_message); /* This is not a security risk */
4174 addr->message = string_sprintf(
4175 "all hosts%s have been failing for a long time %s",
4176 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"",
4177 ob->delay_after_cutoff
4178 ? US"(and retry time not reached)"
4179 : US"and were last tried after this message arrived");
4180
4181 /* If we are already using fallback hosts, or there are no fallback hosts
4182 defined, convert the result to FAIL to cause a bounce. */
4183
4184 if (addr->host_list == addr->fallback_hosts || !addr->fallback_hosts)
4185 addr->transport_return = FAIL;
4186 }
4187 else
4188 {
4189 const char * s;
4190 if (hosts_retry == hosts_total)
4191 s = "retry time not reached for any host%s";
4192 else if (hosts_fail == hosts_total)
4193 s = "all host address lookups%s failed permanently";
4194 else if (hosts_defer == hosts_total)
4195 s = "all host address lookups%s failed temporarily";
4196 else if (hosts_serial == hosts_total)
4197 s = "connection limit reached for all hosts%s";
4198 else if (hosts_fail+hosts_defer == hosts_total)
4199 s = "all host address lookups%s failed";
4200 else
4201 s = "some host address lookups failed and retry time "
4202 "not reached for other hosts or connection limit reached%s";
4203
4204 addr->message = string_sprintf(s,
4205 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"");
4206 }
4207 }
4208 }
4209
4210 /* Update the database which keeps information about which messages are waiting
4211 for which hosts to become available. For some message-specific errors, the
4212 update_waiting flag is turned off because we don't want follow-on deliveries in
4213 those cases. If this transport instance is explicitly limited to one message
4214 per connection then follow-on deliveries are not possible and there's no need
4215 to create/update the per-transport wait-<transport_name> database. */
4216
4217 if (update_waiting && tblock->connection_max_messages != 1)
4218 transport_update_waiting(hostlist, tblock->name);
4219
4220 END_TRANSPORT:
4221
4222 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
4223
4224 return TRUE; /* Each address has its status */
4225 }
4226
4227 /* vi: aw ai sw=2
4228 */
4229 /* End of transport/smtp.c */
Unnamed repository; edit this file 'description' to name the repository.