Delivery: contined-connection maintaining TLS
[exim.git] / src / src / transports / smtp.c
1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
4
5 /* Copyright (c) University of Cambridge 1995 - 2017 */
6 /* See the file NOTICE for conditions of use and distribution. */
7
8 #include "../exim.h"
9 #include "smtp.h"
10
11
12 /* Options specific to the smtp transport. This transport also supports LMTP
13 over TCP/IP. The options must be in alphabetic order (note that "_" comes
14 before the lower case letters). Some live in the transport_instance block so as
15 to be publicly visible; these are flagged with opt_public. */
16
17 optionlist smtp_transport_options[] = {
18 { "*expand_multi_domain", opt_stringptr | opt_hidden | opt_public,
19 (void *)offsetof(transport_instance, expand_multi_domain) },
20 { "*expand_retry_include_ip_address", opt_stringptr | opt_hidden,
21 (void *)(offsetof(smtp_transport_options_block, expand_retry_include_ip_address)) },
22
23 { "address_retry_include_sender", opt_bool,
24 (void *)offsetof(smtp_transport_options_block, address_retry_include_sender) },
25 { "allow_localhost", opt_bool,
26 (void *)offsetof(smtp_transport_options_block, allow_localhost) },
27 { "authenticated_sender", opt_stringptr,
28 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
29 { "authenticated_sender_force", opt_bool,
30 (void *)offsetof(smtp_transport_options_block, authenticated_sender_force) },
31 { "command_timeout", opt_time,
32 (void *)offsetof(smtp_transport_options_block, command_timeout) },
33 { "connect_timeout", opt_time,
34 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
35 { "connection_max_messages", opt_int | opt_public,
36 (void *)offsetof(transport_instance, connection_max_messages) },
37 { "data_timeout", opt_time,
38 (void *)offsetof(smtp_transport_options_block, data_timeout) },
39 { "delay_after_cutoff", opt_bool,
40 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
41 #ifndef DISABLE_DKIM
42 { "dkim_canon", opt_stringptr,
43 (void *)offsetof(smtp_transport_options_block, dkim.dkim_canon) },
44 { "dkim_domain", opt_stringptr,
45 (void *)offsetof(smtp_transport_options_block, dkim.dkim_domain) },
46 { "dkim_private_key", opt_stringptr,
47 (void *)offsetof(smtp_transport_options_block, dkim.dkim_private_key) },
48 { "dkim_selector", opt_stringptr,
49 (void *)offsetof(smtp_transport_options_block, dkim.dkim_selector) },
50 { "dkim_sign_headers", opt_stringptr,
51 (void *)offsetof(smtp_transport_options_block, dkim.dkim_sign_headers) },
52 { "dkim_strict", opt_stringptr,
53 (void *)offsetof(smtp_transport_options_block, dkim.dkim_strict) },
54 #endif
55 { "dns_qualify_single", opt_bool,
56 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
57 { "dns_search_parents", opt_bool,
58 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
59 { "dnssec_request_domains", opt_stringptr,
60 (void *)offsetof(smtp_transport_options_block, dnssec.request) },
61 { "dnssec_require_domains", opt_stringptr,
62 (void *)offsetof(smtp_transport_options_block, dnssec.require) },
63 { "dscp", opt_stringptr,
64 (void *)offsetof(smtp_transport_options_block, dscp) },
65 { "fallback_hosts", opt_stringptr,
66 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
67 { "final_timeout", opt_time,
68 (void *)offsetof(smtp_transport_options_block, final_timeout) },
69 { "gethostbyname", opt_bool,
70 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
71 { "helo_data", opt_stringptr,
72 (void *)offsetof(smtp_transport_options_block, helo_data) },
73 { "hosts", opt_stringptr,
74 (void *)offsetof(smtp_transport_options_block, hosts) },
75 { "hosts_avoid_esmtp", opt_stringptr,
76 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
77 { "hosts_avoid_pipelining", opt_stringptr,
78 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
79 #ifdef SUPPORT_TLS
80 { "hosts_avoid_tls", opt_stringptr,
81 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
82 #endif
83 { "hosts_max_try", opt_int,
84 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
85 { "hosts_max_try_hardlimit", opt_int,
86 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
87 #ifdef SUPPORT_TLS
88 { "hosts_nopass_tls", opt_stringptr,
89 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
90 { "hosts_noproxy_tls", opt_stringptr,
91 (void *)offsetof(smtp_transport_options_block, hosts_noproxy_tls) },
92 #endif
93 { "hosts_override", opt_bool,
94 (void *)offsetof(smtp_transport_options_block, hosts_override) },
95 { "hosts_randomize", opt_bool,
96 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
97 #if defined(SUPPORT_TLS) && !defined(DISABLE_OCSP)
98 { "hosts_request_ocsp", opt_stringptr,
99 (void *)offsetof(smtp_transport_options_block, hosts_request_ocsp) },
100 #endif
101 { "hosts_require_auth", opt_stringptr,
102 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
103 #ifdef SUPPORT_TLS
104 # ifdef EXPERIMENTAL_DANE
105 { "hosts_require_dane", opt_stringptr,
106 (void *)offsetof(smtp_transport_options_block, hosts_require_dane) },
107 # endif
108 # ifndef DISABLE_OCSP
109 { "hosts_require_ocsp", opt_stringptr,
110 (void *)offsetof(smtp_transport_options_block, hosts_require_ocsp) },
111 # endif
112 { "hosts_require_tls", opt_stringptr,
113 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
114 #endif
115 { "hosts_try_auth", opt_stringptr,
116 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
117 { "hosts_try_chunking", opt_stringptr,
118 (void *)offsetof(smtp_transport_options_block, hosts_try_chunking) },
119 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
120 { "hosts_try_dane", opt_stringptr,
121 (void *)offsetof(smtp_transport_options_block, hosts_try_dane) },
122 #endif
123 { "hosts_try_fastopen", opt_stringptr,
124 (void *)offsetof(smtp_transport_options_block, hosts_try_fastopen) },
125 #ifndef DISABLE_PRDR
126 { "hosts_try_prdr", opt_stringptr,
127 (void *)offsetof(smtp_transport_options_block, hosts_try_prdr) },
128 #endif
129 #ifdef SUPPORT_TLS
130 { "hosts_verify_avoid_tls", opt_stringptr,
131 (void *)offsetof(smtp_transport_options_block, hosts_verify_avoid_tls) },
132 #endif
133 { "interface", opt_stringptr,
134 (void *)offsetof(smtp_transport_options_block, interface) },
135 { "keepalive", opt_bool,
136 (void *)offsetof(smtp_transport_options_block, keepalive) },
137 { "lmtp_ignore_quota", opt_bool,
138 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
139 { "max_rcpt", opt_int | opt_public,
140 (void *)offsetof(transport_instance, max_addresses) },
141 { "multi_domain", opt_expand_bool | opt_public,
142 (void *)offsetof(transport_instance, multi_domain) },
143 { "port", opt_stringptr,
144 (void *)offsetof(smtp_transport_options_block, port) },
145 { "protocol", opt_stringptr,
146 (void *)offsetof(smtp_transport_options_block, protocol) },
147 { "retry_include_ip_address", opt_expand_bool,
148 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
149 { "serialize_hosts", opt_stringptr,
150 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
151 { "size_addition", opt_int,
152 (void *)offsetof(smtp_transport_options_block, size_addition) }
153 #ifdef SUPPORT_SOCKS
154 ,{ "socks_proxy", opt_stringptr,
155 (void *)offsetof(smtp_transport_options_block, socks_proxy) }
156 #endif
157 #ifdef SUPPORT_TLS
158 ,{ "tls_certificate", opt_stringptr,
159 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
160 { "tls_crl", opt_stringptr,
161 (void *)offsetof(smtp_transport_options_block, tls_crl) },
162 { "tls_dh_min_bits", opt_int,
163 (void *)offsetof(smtp_transport_options_block, tls_dh_min_bits) },
164 { "tls_privatekey", opt_stringptr,
165 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
166 { "tls_require_ciphers", opt_stringptr,
167 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
168 { "tls_sni", opt_stringptr,
169 (void *)offsetof(smtp_transport_options_block, tls_sni) },
170 { "tls_tempfail_tryclear", opt_bool,
171 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
172 { "tls_try_verify_hosts", opt_stringptr,
173 (void *)offsetof(smtp_transport_options_block, tls_try_verify_hosts) },
174 { "tls_verify_cert_hostnames", opt_stringptr,
175 (void *)offsetof(smtp_transport_options_block,tls_verify_cert_hostnames)},
176 { "tls_verify_certificates", opt_stringptr,
177 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) },
178 { "tls_verify_hosts", opt_stringptr,
179 (void *)offsetof(smtp_transport_options_block, tls_verify_hosts) }
180 #endif
181 };
182
183 /* Size of the options list. An extern variable has to be used so that its
184 address can appear in the tables drtables.c. */
185
186 int smtp_transport_options_count =
187 sizeof(smtp_transport_options)/sizeof(optionlist);
188
189 /* Default private options block for the smtp transport. */
190
191 smtp_transport_options_block smtp_transport_option_defaults = {
192 NULL, /* hosts */
193 NULL, /* fallback_hosts */
194 NULL, /* hostlist */
195 NULL, /* fallback_hostlist */
196 NULL, /* authenticated_sender */
197 US"$primary_hostname", /* helo_data */
198 NULL, /* interface */
199 NULL, /* port */
200 US"smtp", /* protocol */
201 NULL, /* DSCP */
202 NULL, /* serialize_hosts */
203 NULL, /* hosts_try_auth */
204 NULL, /* hosts_require_auth */
205 US"*", /* hosts_try_chunking */
206 #ifdef EXPERIMENTAL_DANE
207 NULL, /* hosts_try_dane */
208 NULL, /* hosts_require_dane */
209 #endif
210 NULL, /* hosts_try_fastopen */
211 #ifndef DISABLE_PRDR
212 US"*", /* hosts_try_prdr */
213 #endif
214 #ifndef DISABLE_OCSP
215 US"*", /* hosts_request_ocsp (except under DANE; tls_client_start()) */
216 NULL, /* hosts_require_ocsp */
217 #endif
218 NULL, /* hosts_require_tls */
219 NULL, /* hosts_avoid_tls */
220 NULL, /* hosts_verify_avoid_tls */
221 NULL, /* hosts_avoid_pipelining */
222 NULL, /* hosts_avoid_esmtp */
223 NULL, /* hosts_nopass_tls */
224 US"*", /* hosts_noproxy_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 uschar *data_command = US""; /* Points to DATA cmd for error messages */
288 static BOOL update_waiting; /* TRUE to update the "wait" database */
289
290 /*XXX move to smtp_context */
291 static BOOL pipelining_active; /* current transaction is in pipe mode */
292
293
294 /*************************************************
295 * Setup entry point *
296 *************************************************/
297
298 /* This function is called when the transport is about to be used,
299 but before running it in a sub-process. It is used for two things:
300
301 (1) To set the fallback host list in addresses, when delivering.
302 (2) To pass back the interface, port, protocol, and other options, for use
303 during callout verification.
304
305 Arguments:
306 tblock pointer to the transport instance block
307 addrlist list of addresses about to be transported
308 tf if not NULL, pointer to block in which to return options
309 uid the uid that will be set (not used)
310 gid the gid that will be set (not used)
311 errmsg place for error message (not used)
312
313 Returns: OK always (FAIL, DEFER not used)
314 */
315
316 static int
317 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
318 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
319 {
320 smtp_transport_options_block *ob =
321 (smtp_transport_options_block *)(tblock->options_block);
322
323 errmsg = errmsg; /* Keep picky compilers happy */
324 uid = uid;
325 gid = gid;
326
327 /* Pass back options if required. This interface is getting very messy. */
328
329 if (tf)
330 {
331 tf->interface = ob->interface;
332 tf->port = ob->port;
333 tf->protocol = ob->protocol;
334 tf->hosts = ob->hosts;
335 tf->hosts_override = ob->hosts_override;
336 tf->hosts_randomize = ob->hosts_randomize;
337 tf->gethostbyname = ob->gethostbyname;
338 tf->qualify_single = ob->dns_qualify_single;
339 tf->search_parents = ob->dns_search_parents;
340 tf->helo_data = ob->helo_data;
341 }
342
343 /* Set the fallback host list for all the addresses that don't have fallback
344 host lists, provided that the local host wasn't present in the original host
345 list. */
346
347 if (!testflag(addrlist, af_local_host_removed))
348 for (; addrlist; addrlist = addrlist->next)
349 if (!addrlist->fallback_hosts) addrlist->fallback_hosts = ob->fallback_hostlist;
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)
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 error 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 const uschar * s;
519
520 *yield = '4'; /* Default setting is to give a temporary error */
521
522 switch(*errno_value)
523 {
524 case ETIMEDOUT: /* Handle response timeout */
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 case ERRNO_SMTPFORMAT: /* Handle malformed SMTP response */
533 s = string_printing(buffer);
534 while (isspace(*s)) s++;
535 *message = *s == 0
536 ? string_sprintf("Malformed SMTP reply (an empty line) "
537 "in response to %s%s", pl, smtp_command)
538 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
539 pl, smtp_command, s);
540 return FALSE;
541
542 case ERRNO_FILTER_FAIL: /* Handle a failed filter process error;
543 can't send QUIT as we mustn't end the DATA. */
544 *message = string_sprintf("transport filter process failed (%d)%s",
545 more_errno,
546 more_errno == EX_EXECFAILED ? ": unable to execute command" : "");
547 return FALSE;
548
549 case ERRNO_CHHEADER_FAIL: /* Handle a failed add_headers expansion;
550 can't send QUIT as we mustn't end the DATA. */
551 *message =
552 string_sprintf("failed to expand headers_add or headers_remove: %s",
553 expand_string_message);
554 return FALSE;
555
556 case ERRNO_WRITEINCOMPLETE: /* failure to write a complete data block */
557 *message = string_sprintf("failed to write a data block");
558 return FALSE;
559
560 #ifdef SUPPORT_I18N
561 case ERRNO_UTF8_FWD: /* no advertised SMTPUTF8, for international message */
562 *message = US"utf8 support required but not offered for forwarding";
563 DEBUG(D_deliver|D_transport) debug_printf("%s\n", *message);
564 return TRUE;
565 #endif
566 }
567
568 /* Handle error responses from the remote mailer. */
569
570 if (buffer[0] != 0)
571 {
572 *message = string_sprintf("SMTP error from remote mail server after %s%s: "
573 "%s", pl, smtp_command, s = string_printing(buffer));
574 *pass_message = TRUE;
575 *yield = buffer[0];
576 return TRUE;
577 }
578
579 /* No data was read. If there is no errno, this must be the EOF (i.e.
580 connection closed) case, which causes deferral. An explicit connection reset
581 error has the same effect. Otherwise, put the host's identity in the message,
582 leaving the errno value to be interpreted as well. In all cases, we have to
583 assume the connection is now dead. */
584
585 if (*errno_value == 0 || *errno_value == ECONNRESET)
586 {
587 *errno_value = ERRNO_SMTPCLOSED;
588 *message = US string_sprintf("Remote host closed connection "
589 "in response to %s%s", pl, smtp_command);
590 }
591 else
592 *message = US string_sprintf("%s [%s]", host->name, host->address);
593
594 return FALSE;
595 }
596
597
598
599 /*************************************************
600 * Write error message to logs *
601 *************************************************/
602
603 /* This writes to the main log and to the message log.
604
605 Arguments:
606 addr the address item containing error information
607 host the current host
608
609 Returns: nothing
610 */
611
612 static void
613 write_logs(address_item *addr, host_item *host)
614 {
615 uschar * message = LOGGING(outgoing_port)
616 ? string_sprintf("H=%s [%s]:%d", host->name, host->address,
617 host->port == PORT_NONE ? 25 : host->port)
618 : string_sprintf("H=%s [%s]", host->name, host->address);
619
620 if (addr->message)
621 {
622 message = string_sprintf("%s: %s", message, addr->message);
623 if (addr->basic_errno > 0)
624 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
625 log_write(0, LOG_MAIN, "%s", message);
626 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
627 }
628 else
629 {
630 const uschar * s = exim_errstr(addr->basic_errno);
631 log_write(0, LOG_MAIN, "%s %s", message, s);
632 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), message, s);
633 }
634 }
635
636 static void
637 msglog_line(host_item * host, uschar * message)
638 {
639 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
640 host->name, host->address, message);
641 }
642
643
644
645 #ifndef DISABLE_EVENT
646 /*************************************************
647 * Post-defer action *
648 *************************************************/
649
650 /* This expands an arbitrary per-transport string.
651 It might, for example, be used to write to the database log.
652
653 Arguments:
654 addr the address item containing error information
655 host the current host
656
657 Returns: nothing
658 */
659
660 static void
661 deferred_event_raise(address_item *addr, host_item *host)
662 {
663 uschar * action = addr->transport->event_action;
664 const uschar * save_domain;
665 uschar * save_local;
666
667 if (!action)
668 return;
669
670 save_domain = deliver_domain;
671 save_local = deliver_localpart;
672
673 /*XXX would ip & port already be set up? */
674 deliver_host_address = string_copy(host->address);
675 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
676 event_defer_errno = addr->basic_errno;
677
678 router_name = addr->router->name;
679 transport_name = addr->transport->name;
680 deliver_domain = addr->domain;
681 deliver_localpart = addr->local_part;
682
683 (void) event_raise(action, US"msg:host:defer",
684 addr->message
685 ? addr->basic_errno > 0
686 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
687 : string_copy(addr->message)
688 : addr->basic_errno > 0
689 ? string_copy(US strerror(addr->basic_errno))
690 : NULL);
691
692 deliver_localpart = save_local;
693 deliver_domain = save_domain;
694 router_name = transport_name = NULL;
695 }
696 #endif
697
698 /*************************************************
699 * Synchronize SMTP responses *
700 *************************************************/
701
702 /* This function is called from smtp_deliver() to receive SMTP responses from
703 the server, and match them up with the commands to which they relate. When
704 PIPELINING is not in use, this function is called after every command, and is
705 therefore somewhat over-engineered, but it is simpler to use a single scheme
706 that works both with and without PIPELINING instead of having two separate sets
707 of code.
708
709 The set of commands that are buffered up with pipelining may start with MAIL
710 and may end with DATA; in between are RCPT commands that correspond to the
711 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
712 etc.) are never buffered.
713
714 Errors after MAIL or DATA abort the whole process leaving the response in the
715 buffer. After MAIL, pending responses are flushed, and the original command is
716 re-instated in big_buffer for error messages. For RCPT commands, the remote is
717 permitted to reject some recipient addresses while accepting others. However
718 certain errors clearly abort the whole process. Set the value in
719 transport_return to PENDING_OK if the address is accepted. If there is a
720 subsequent general error, it will get reset accordingly. If not, it will get
721 converted to OK at the end.
722
723 Arguments:
724 sx smtp connection context
725 count the number of responses to read
726 pending_DATA 0 if last command sent was not DATA
727 +1 if previously had a good recipient
728 -1 if not previously had a good recipient
729
730 Returns: 3 if at least one address had 2xx and one had 5xx
731 2 if at least one address had 5xx but none had 2xx
732 1 if at least one host had a 2xx response, but none had 5xx
733 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
734 -1 timeout while reading RCPT response
735 -2 I/O or other non-response error for RCPT
736 -3 DATA or MAIL failed - errno and buffer set
737 */
738
739 static int
740 sync_responses(smtp_context * sx, int count, int pending_DATA)
741 {
742 address_item *addr = sx->sync_addr;
743 smtp_transport_options_block *ob =
744 (smtp_transport_options_block *)sx->tblock->options_block;
745 int yield = 0;
746
747 /* Handle the response for a MAIL command. On error, reinstate the original
748 command in big_buffer for error message use, and flush any further pending
749 responses before returning, except after I/O errors and timeouts. */
750
751 if (sx->pending_MAIL)
752 {
753 count--;
754 if (!smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
755 '2', ob->command_timeout))
756 {
757 DEBUG(D_transport) debug_printf("bad response for MAIL\n");
758 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
759 if (errno == 0 && sx->buffer[0] != 0)
760 {
761 uschar flushbuffer[4096];
762 int save_errno = 0;
763 if (sx->buffer[0] == '4')
764 {
765 save_errno = ERRNO_MAIL4XX;
766 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
767 }
768 while (count-- > 0)
769 {
770 if (!smtp_read_response(&sx->inblock, flushbuffer, sizeof(flushbuffer),
771 '2', ob->command_timeout)
772 && (errno != 0 || flushbuffer[0] == 0))
773 break;
774 }
775 errno = save_errno;
776 }
777
778 if (pending_DATA) count--; /* Number of RCPT responses to come */
779 while (count-- > 0) /* Mark any pending addrs with the host used */
780 {
781 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
782 addr->host_used = sx->host;
783 addr = addr->next;
784 }
785 return -3;
786 }
787 }
788
789 if (pending_DATA) count--; /* Number of RCPT responses to come */
790
791 /* Read and handle the required number of RCPT responses, matching each one up
792 with an address by scanning for the next address whose status is PENDING_DEFER.
793 */
794
795 while (count-- > 0)
796 {
797 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
798
799 /* The address was accepted */
800 addr->host_used = sx->host;
801
802 if (smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
803 '2', ob->command_timeout))
804 {
805 yield |= 1;
806 addr->transport_return = PENDING_OK;
807
808 /* If af_dr_retry_exists is set, there was a routing delay on this address;
809 ensure that any address-specific retry record is expunged. We do this both
810 for the basic key and for the version that also includes the sender. */
811
812 if (testflag(addr, af_dr_retry_exists))
813 {
814 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
815 sender_address);
816 retry_add_item(addr, altkey, rf_delete);
817 retry_add_item(addr, addr->address_retry_key, rf_delete);
818 }
819 }
820
821 /* Timeout while reading the response */
822
823 else if (errno == ETIMEDOUT)
824 {
825 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
826 transport_rcpt_address(addr, sx->tblock->rcpt_include_affixes));
827 set_errno_nohost(sx->first_addr, ETIMEDOUT, message, DEFER, FALSE);
828 retry_add_item(addr, addr->address_retry_key, 0);
829 update_waiting = FALSE;
830 return -1;
831 }
832
833 /* Handle other errors in obtaining an SMTP response by returning -1. This
834 will cause all the addresses to be deferred. Restore the SMTP command in
835 big_buffer for which we are checking the response, so the error message
836 makes sense. */
837
838 else if (errno != 0 || sx->buffer[0] == 0)
839 {
840 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
841 transport_rcpt_address(addr, sx->tblock->rcpt_include_affixes));
842 return -2;
843 }
844
845 /* Handle SMTP permanent and temporary response codes. */
846
847 else
848 {
849 addr->message =
850 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
851 "%s", transport_rcpt_address(addr, sx->tblock->rcpt_include_affixes),
852 string_printing(sx->buffer));
853 setflag(addr, af_pass_message);
854 if (!sx->verify)
855 msglog_line(sx->host, addr->message);
856
857 /* The response was 5xx */
858
859 if (sx->buffer[0] == '5')
860 {
861 addr->transport_return = FAIL;
862 yield |= 2;
863 }
864
865 /* The response was 4xx */
866
867 else
868 {
869 addr->transport_return = DEFER;
870 addr->basic_errno = ERRNO_RCPT4XX;
871 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
872
873 if (!sx->verify)
874 {
875 #ifndef DISABLE_EVENT
876 event_defer_errno = addr->more_errno;
877 msg_event_raise(US"msg:rcpt:host:defer", addr);
878 #endif
879
880 /* Log temporary errors if there are more hosts to be tried.
881 If not, log this last one in the == line. */
882
883 if (sx->host->next)
884 log_write(0, LOG_MAIN, "H=%s [%s]: %s",
885 sx->host->name, sx->host->address, addr->message);
886
887 #ifndef DISABLE_EVENT
888 else
889 msg_event_raise(US"msg:rcpt:defer", addr);
890 #endif
891
892 /* Do not put this message on the list of those waiting for specific
893 hosts, as otherwise it is likely to be tried too often. */
894
895 update_waiting = FALSE;
896
897 /* Add a retry item for the address so that it doesn't get tried again
898 too soon. If address_retry_include_sender is true, add the sender address
899 to the retry key. */
900
901 retry_add_item(addr,
902 ob->address_retry_include_sender
903 ? string_sprintf("%s:<%s>", addr->address_retry_key, sender_address)
904 : addr->address_retry_key,
905 0);
906 }
907 }
908 }
909 } /* Loop for next RCPT response */
910
911 /* Update where to start at for the next block of responses, unless we
912 have already handled all the addresses. */
913
914 if (addr) sx->sync_addr = addr->next;
915
916 /* Handle a response to DATA. If we have not had any good recipients, either
917 previously or in this block, the response is ignored. */
918
919 if (pending_DATA != 0 &&
920 !smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
921 '3', ob->command_timeout))
922 {
923 int code;
924 uschar *msg;
925 BOOL pass_message;
926 if (pending_DATA > 0 || (yield & 1) != 0)
927 {
928 if (errno == 0 && sx->buffer[0] == '4')
929 {
930 errno = ERRNO_DATA4XX;
931 sx->first_addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
932 }
933 return -3;
934 }
935 (void)check_response(sx->host, &errno, 0, sx->buffer, &code, &msg, &pass_message);
936 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
937 "is in use and there were no good recipients\n", msg);
938 }
939
940 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
941 present) received 3xx. If any RCPTs were handled and yielded anything other
942 than 4xx, yield will be set non-zero. */
943
944 return yield;
945 }
946
947
948
949 /* Do the client side of smtp-level authentication */
950 /*
951 Arguments:
952 buffer EHLO response from server (gets overwritten)
953 addrlist chain of potential addresses to deliver
954 host host to deliver to
955 ob transport options
956 ibp, obp comms channel control blocks
957
958 Returns:
959 OK Success, or failed (but not required): global "smtp_authenticated" set
960 DEFER Failed authentication (and was required)
961 ERROR Internal problem
962
963 FAIL_SEND Failed communications - transmit
964 FAIL - response
965 */
966
967 int
968 smtp_auth(uschar *buffer, unsigned bufsize, address_item *addrlist, host_item *host,
969 smtp_transport_options_block *ob, BOOL is_esmtp,
970 smtp_inblock *ibp, smtp_outblock *obp)
971 {
972 int require_auth;
973 uschar *fail_reason = US"server did not advertise AUTH support";
974
975 smtp_authenticated = FALSE;
976 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
977 require_auth = verify_check_given_host(&ob->hosts_require_auth, host);
978
979 if (is_esmtp && !regex_AUTH) regex_AUTH =
980 regex_must_compile(US"\\n250[\\s\\-]AUTH\\s+([\\-\\w\\s]+)(?:\\n|$)",
981 FALSE, TRUE);
982
983 if (is_esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
984 {
985 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
986 expand_nmax = -1; /* reset */
987
988 /* Must not do this check until after we have saved the result of the
989 regex match above. */
990
991 if (require_auth == OK ||
992 verify_check_given_host(&ob->hosts_try_auth, host) == OK)
993 {
994 auth_instance *au;
995 fail_reason = US"no common mechanisms were found";
996
997 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
998
999 /* Scan the configured authenticators looking for one which is configured
1000 for use as a client, which is not suppressed by client_condition, and
1001 whose name matches an authentication mechanism supported by the server.
1002 If one is found, attempt to authenticate by calling its client function.
1003 */
1004
1005 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1006 {
1007 uschar *p = names;
1008 if (!au->client ||
1009 (au->client_condition != NULL &&
1010 !expand_check_condition(au->client_condition, au->name,
1011 US"client authenticator")))
1012 {
1013 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1014 au->name,
1015 (au->client)? "client_condition is false" :
1016 "not configured as a client");
1017 continue;
1018 }
1019
1020 /* Loop to scan supported server mechanisms */
1021
1022 while (*p != 0)
1023 {
1024 int rc;
1025 int len = Ustrlen(au->public_name);
1026 while (isspace(*p)) p++;
1027
1028 if (strncmpic(au->public_name, p, len) != 0 ||
1029 (p[len] != 0 && !isspace(p[len])))
1030 {
1031 while (*p != 0 && !isspace(*p)) p++;
1032 continue;
1033 }
1034
1035 /* Found data for a listed mechanism. Call its client entry. Set
1036 a flag in the outblock so that data is overwritten after sending so
1037 that reflections don't show it. */
1038
1039 fail_reason = US"authentication attempt(s) failed";
1040 obp->authenticating = TRUE;
1041 rc = (au->info->clientcode)(au, ibp, obp,
1042 ob->command_timeout, buffer, bufsize);
1043 obp->authenticating = FALSE;
1044 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1045 au->name, rc);
1046
1047 /* A temporary authentication failure must hold up delivery to
1048 this host. After a permanent authentication failure, we carry on
1049 to try other authentication methods. If all fail hard, try to
1050 deliver the message unauthenticated unless require_auth was set. */
1051
1052 switch(rc)
1053 {
1054 case OK:
1055 smtp_authenticated = TRUE; /* stops the outer loop */
1056 client_authenticator = au->name;
1057 if (au->set_client_id != NULL)
1058 client_authenticated_id = expand_string(au->set_client_id);
1059 break;
1060
1061 /* Failure after writing a command */
1062
1063 case FAIL_SEND:
1064 return FAIL_SEND;
1065
1066 /* Failure after reading a response */
1067
1068 case FAIL:
1069 if (errno != 0 || buffer[0] != '5') return FAIL;
1070 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1071 au->name, host->name, host->address, buffer);
1072 break;
1073
1074 /* Failure by some other means. In effect, the authenticator
1075 decided it wasn't prepared to handle this case. Typically this
1076 is the result of "fail" in an expansion string. Do we need to
1077 log anything here? Feb 2006: a message is now put in the buffer
1078 if logging is required. */
1079
1080 case CANCELLED:
1081 if (*buffer != 0)
1082 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1083 "authentication H=%s [%s] %s", au->name, host->name,
1084 host->address, buffer);
1085 break;
1086
1087 /* Internal problem, message in buffer. */
1088
1089 case ERROR:
1090 set_errno_nohost(addrlist, ERRNO_AUTHPROB, string_copy(buffer),
1091 DEFER, FALSE);
1092 return ERROR;
1093 }
1094
1095 break; /* If not authenticated, try next authenticator */
1096 } /* Loop for scanning supported server mechanisms */
1097 } /* Loop for further authenticators */
1098 }
1099 }
1100
1101 /* If we haven't authenticated, but are required to, give up. */
1102
1103 if (require_auth == OK && !smtp_authenticated)
1104 {
1105 set_errno_nohost(addrlist, ERRNO_AUTHFAIL,
1106 string_sprintf("authentication required but %s", fail_reason), DEFER,
1107 FALSE);
1108 return DEFER;
1109 }
1110
1111 return OK;
1112 }
1113
1114
1115 /* Construct AUTH appendix string for MAIL TO */
1116 /*
1117 Arguments
1118 buffer to build string
1119 addrlist chain of potential addresses to deliver
1120 ob transport options
1121
1122 Globals smtp_authenticated
1123 client_authenticated_sender
1124 Return True on error, otherwise buffer has (possibly empty) terminated string
1125 */
1126
1127 BOOL
1128 smtp_mail_auth_str(uschar *buffer, unsigned bufsize, address_item *addrlist,
1129 smtp_transport_options_block *ob)
1130 {
1131 uschar *local_authenticated_sender = authenticated_sender;
1132
1133 #ifdef notdef
1134 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n", authenticated_sender, ob->authenticated_sender, smtp_authenticated?"Y":"N");
1135 #endif
1136
1137 if (ob->authenticated_sender != NULL)
1138 {
1139 uschar *new = expand_string(ob->authenticated_sender);
1140 if (new == NULL)
1141 {
1142 if (!expand_string_forcedfail)
1143 {
1144 uschar *message = string_sprintf("failed to expand "
1145 "authenticated_sender: %s", expand_string_message);
1146 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1147 return TRUE;
1148 }
1149 }
1150 else if (new[0] != 0) local_authenticated_sender = new;
1151 }
1152
1153 /* Add the authenticated sender address if present */
1154
1155 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1156 local_authenticated_sender != NULL)
1157 {
1158 string_format(buffer, bufsize, " AUTH=%s",
1159 auth_xtextencode(local_authenticated_sender,
1160 Ustrlen(local_authenticated_sender)));
1161 client_authenticated_sender = string_copy(local_authenticated_sender);
1162 }
1163 else
1164 *buffer= 0;
1165
1166 return FALSE;
1167 }
1168
1169
1170
1171 #ifdef EXPERIMENTAL_DANE
1172 /* Lookup TLSA record for host/port.
1173 Return: OK success with dnssec; DANE mode
1174 DEFER Do not use this host now, may retry later
1175 FAIL_FORCED No TLSA record; DANE not usable
1176 FAIL Do not use this connection
1177 */
1178
1179 int
1180 tlsa_lookup(const host_item * host, dns_answer * dnsa, BOOL dane_required)
1181 {
1182 /* move this out to host.c given the similarity to dns_lookup() ? */
1183 uschar buffer[300];
1184 const uschar * fullname = buffer;
1185
1186 /* TLSA lookup string */
1187 (void)sprintf(CS buffer, "_%d._tcp.%.256s", host->port, host->name);
1188
1189 switch (dns_lookup(dnsa, buffer, T_TLSA, &fullname))
1190 {
1191 case DNS_SUCCEED:
1192 if (!dns_is_secure(dnsa))
1193 {
1194 log_write(0, LOG_MAIN, "DANE error: TLSA lookup not DNSSEC");
1195 return DEFER;
1196 }
1197 return OK;
1198
1199 case DNS_AGAIN:
1200 return DEFER; /* just defer this TLS'd conn */
1201
1202 case DNS_NODATA: /* no TLSA RR for this lookup */
1203 case DNS_NOMATCH: /* no records at all for this lookup */
1204 return dane_required ? FAIL : FAIL_FORCED;
1205
1206 default:
1207 case DNS_FAIL:
1208 return dane_required ? FAIL : DEFER;
1209 }
1210 }
1211 #endif
1212
1213
1214
1215 typedef struct smtp_compare_s
1216 {
1217 uschar *current_sender_address;
1218 struct transport_instance *tblock;
1219 } smtp_compare_t;
1220
1221
1222 /* Create a unique string that identifies this message, it is based on
1223 sender_address, helo_data and tls_certificate if enabled.
1224 */
1225
1226 static uschar *
1227 smtp_local_identity(uschar * sender, struct transport_instance * tblock)
1228 {
1229 address_item * addr1;
1230 uschar * if1 = US"";
1231 uschar * helo1 = US"";
1232 #ifdef SUPPORT_TLS
1233 uschar * tlsc1 = US"";
1234 #endif
1235 uschar * save_sender_address = sender_address;
1236 uschar * local_identity = NULL;
1237 smtp_transport_options_block * ob =
1238 (smtp_transport_options_block *)tblock->options_block;
1239
1240 sender_address = sender;
1241
1242 addr1 = deliver_make_addr (sender, TRUE);
1243 deliver_set_expansions(addr1);
1244
1245 if (ob->interface)
1246 if1 = expand_string(ob->interface);
1247
1248 if (ob->helo_data)
1249 helo1 = expand_string(ob->helo_data);
1250
1251 #ifdef SUPPORT_TLS
1252 if (ob->tls_certificate)
1253 tlsc1 = expand_string(ob->tls_certificate);
1254 local_identity = string_sprintf ("%s^%s^%s", if1, helo1, tlsc1);
1255 #else
1256 local_identity = string_sprintf ("%s^%s", if1, helo1);
1257 #endif
1258
1259 deliver_set_expansions(NULL);
1260 sender_address = save_sender_address;
1261
1262 return local_identity;
1263 }
1264
1265
1266
1267 /* This routine is a callback that is called from transport_check_waiting.
1268 This function will evaluate the incoming message versus the previous
1269 message. If the incoming message is using a different local identity then
1270 we will veto this new message. */
1271
1272 static BOOL
1273 smtp_are_same_identities(uschar * message_id, smtp_compare_t * s_compare)
1274 {
1275 uschar * message_local_identity,
1276 * current_local_identity,
1277 * new_sender_address;
1278
1279 current_local_identity =
1280 smtp_local_identity(s_compare->current_sender_address, s_compare->tblock);
1281
1282 if (!(new_sender_address = deliver_get_sender_address(message_id)))
1283 return 0;
1284
1285 message_local_identity =
1286 smtp_local_identity(new_sender_address, s_compare->tblock);
1287
1288 return Ustrcmp(current_local_identity, message_local_identity) == 0;
1289 }
1290
1291
1292
1293 static uschar
1294 ehlo_response(uschar * buf, uschar checks)
1295 {
1296 size_t bsize = Ustrlen(buf);
1297
1298 #ifdef SUPPORT_TLS
1299 if ( checks & PEER_OFFERED_TLS
1300 && pcre_exec(regex_STARTTLS, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1301 checks &= ~PEER_OFFERED_TLS;
1302 #endif
1303
1304 if ( checks & PEER_OFFERED_IGNQ
1305 && pcre_exec(regex_IGNOREQUOTA, NULL, CS buf, bsize, 0,
1306 PCRE_EOPT, NULL, 0) < 0)
1307 checks &= ~PEER_OFFERED_IGNQ;
1308
1309 if ( checks & PEER_OFFERED_CHUNKING
1310 && pcre_exec(regex_CHUNKING, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1311 checks &= ~PEER_OFFERED_CHUNKING;
1312
1313 #ifndef DISABLE_PRDR
1314 if ( checks & PEER_OFFERED_PRDR
1315 && pcre_exec(regex_PRDR, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1316 checks &= ~PEER_OFFERED_PRDR;
1317 #endif
1318
1319 #ifdef SUPPORT_I18N
1320 if ( checks & PEER_OFFERED_UTF8
1321 && pcre_exec(regex_UTF8, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1322 checks &= ~PEER_OFFERED_UTF8;
1323 #endif
1324
1325 if ( checks & PEER_OFFERED_DSN
1326 && pcre_exec(regex_DSN, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1327 checks &= ~PEER_OFFERED_DSN;
1328
1329 if ( checks & PEER_OFFERED_PIPE
1330 && pcre_exec(regex_PIPELINING, NULL, CS buf, bsize, 0,
1331 PCRE_EOPT, NULL, 0) < 0)
1332 checks &= ~PEER_OFFERED_PIPE;
1333
1334 if ( checks & PEER_OFFERED_SIZE
1335 && pcre_exec(regex_SIZE, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1336 checks &= ~PEER_OFFERED_SIZE;
1337
1338 return checks;
1339 }
1340
1341
1342
1343 /* Callback for emitting a BDAT data chunk header.
1344
1345 If given a nonzero size, first flush any buffered SMTP commands
1346 then emit the command.
1347
1348 Reap previous SMTP command responses if requested.
1349 Reap one SMTP command response if requested.
1350
1351 Returns: OK or ERROR
1352 */
1353
1354 static int
1355 smtp_chunk_cmd_callback(int fd, transport_ctx * tctx,
1356 unsigned chunk_size, unsigned flags)
1357 {
1358 smtp_transport_options_block * ob =
1359 (smtp_transport_options_block *)(tctx->tblock->options_block);
1360 smtp_context * sx = tctx->smtp_context;
1361 int cmd_count = 0;
1362 int prev_cmd_count;
1363
1364 /* Write SMTP chunk header command */
1365
1366 if (chunk_size > 0)
1367 {
1368 if((cmd_count = smtp_write_command(&sx->outblock, FALSE, "BDAT %u%s\r\n",
1369 chunk_size,
1370 flags & tc_chunk_last ? " LAST" : "")
1371 ) < 0) return ERROR;
1372 if (flags & tc_chunk_last)
1373 data_command = string_copy(big_buffer); /* Save for later error message */
1374 }
1375
1376 prev_cmd_count = cmd_count += sx->cmd_count;
1377
1378 /* Reap responses for any previous, but not one we just emitted */
1379
1380 if (chunk_size > 0)
1381 prev_cmd_count--;
1382 if (sx->pending_BDAT)
1383 prev_cmd_count--;
1384
1385 if (flags & tc_reap_prev && prev_cmd_count > 0)
1386 {
1387 DEBUG(D_transport) debug_printf("look for %d responses"
1388 " for previous pipelined cmds\n", prev_cmd_count);
1389
1390 switch(sync_responses(sx, prev_cmd_count, 0))
1391 {
1392 case 1: /* 2xx (only) => OK */
1393 case 3: sx->good_RCPT = TRUE; /* 2xx & 5xx => OK & progress made */
1394 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
1395 case 0: break; /* No 2xx or 5xx, but no probs */
1396
1397 case -1: /* Timeout on RCPT */
1398 default: return ERROR; /* I/O error, or any MAIL/DATA error */
1399 }
1400 cmd_count = 1;
1401 if (!sx->pending_BDAT)
1402 pipelining_active = FALSE;
1403 }
1404
1405 /* Reap response for an outstanding BDAT */
1406
1407 if (sx->pending_BDAT)
1408 {
1409 DEBUG(D_transport) debug_printf("look for one response for BDAT\n");
1410
1411 if (!smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer), '2',
1412 ob->command_timeout))
1413 {
1414 if (errno == 0 && sx->buffer[0] == '4')
1415 {
1416 errno = ERRNO_DATA4XX; /*XXX does this actually get used? */
1417 sx->addrlist->more_errno |=
1418 ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1419 }
1420 return ERROR;
1421 }
1422 cmd_count--;
1423 sx->pending_BDAT = FALSE;
1424 pipelining_active = FALSE;
1425 }
1426 else if (chunk_size > 0)
1427 sx->pending_BDAT = TRUE;
1428
1429
1430 sx->cmd_count = cmd_count;
1431 return OK;
1432 }
1433
1434
1435
1436 /*************************************************
1437 * Make connection for given message *
1438 *************************************************/
1439
1440 /*
1441 Arguments:
1442 ctx connection context
1443 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1444 a second attempt after TLS initialization fails
1445
1446 Returns: OK - the connection was made and the delivery attempted;
1447 fd is set in the conn context, tls_out set up.
1448 DEFER - the connection could not be made, or something failed
1449 while setting up the SMTP session, or there was a
1450 non-message-specific error, such as a timeout.
1451 ERROR - helo_data or add_headers or authenticated_sender is
1452 specified for this transport, and the string failed
1453 to expand
1454 */
1455 int
1456 smtp_setup_conn(smtp_context * sx, BOOL suppress_tls)
1457 {
1458 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1459 dns_answer tlsa_dnsa;
1460 #endif
1461 BOOL pass_message = FALSE;
1462 uschar * message = NULL;
1463 int yield = OK;
1464 int rc;
1465
1466 sx->ob = (smtp_transport_options_block *) sx->tblock->options_block;
1467
1468 sx->lmtp = strcmpic(sx->ob->protocol, US"lmtp") == 0;
1469 sx->smtps = strcmpic(sx->ob->protocol, US"smtps") == 0;
1470 sx->ok = FALSE;
1471 sx->send_rset = TRUE;
1472 sx->send_quit = TRUE;
1473 sx->setting_up = TRUE;
1474 sx->esmtp = TRUE;
1475 sx->esmtp_sent = FALSE;
1476 #ifdef SUPPORT_I18N
1477 sx->utf8_needed = FALSE;
1478 #endif
1479 sx->dsn_all_lasthop = TRUE;
1480 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1481 sx->dane = FALSE;
1482 sx->dane_required = verify_check_given_host(&sx->ob->hosts_require_dane, sx->host) == OK;
1483 #endif
1484
1485 if ((sx->max_rcpt = sx->tblock->max_addresses) == 0) sx->max_rcpt = 999999;
1486 sx->peer_offered = 0;
1487 sx->igquotstr = US"";
1488 if (!sx->helo_data) sx->helo_data = sx->ob->helo_data;
1489 #ifdef EXPERIMENTAL_DSN_INFO
1490 sx->smtp_greeting = NULL;
1491 sx->helo_response = NULL;
1492 #endif
1493
1494 smtp_command = US"initial connection";
1495 sx->buffer[0] = '\0';
1496
1497 /* Set up the buffer for reading SMTP response packets. */
1498
1499 sx->inblock.buffer = sx->inbuffer;
1500 sx->inblock.buffersize = sizeof(sx->inbuffer);
1501 sx->inblock.ptr = sx->inbuffer;
1502 sx->inblock.ptrend = sx->inbuffer;
1503
1504 /* Set up the buffer for holding SMTP commands while pipelining */
1505
1506 sx->outblock.buffer = sx->outbuffer;
1507 sx->outblock.buffersize = sizeof(sx->outbuffer);
1508 sx->outblock.ptr = sx->outbuffer;
1509 sx->outblock.cmd_count = 0;
1510 sx->outblock.authenticating = FALSE;
1511
1512 /* Reset the parameters of a TLS session. */
1513
1514 tls_out.bits = 0;
1515 tls_out.cipher = NULL; /* the one we may use for this transport */
1516 tls_out.ourcert = NULL;
1517 tls_out.peercert = NULL;
1518 tls_out.peerdn = NULL;
1519 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1520 tls_out.sni = NULL;
1521 #endif
1522 tls_out.ocsp = OCSP_NOT_REQ;
1523
1524 /* Flip the legacy TLS-related variables over to the outbound set in case
1525 they're used in the context of the transport. Don't bother resetting
1526 afterward (when being used by a transport) as we're in a subprocess.
1527 For verify, unflipped once the callout is dealt with */
1528
1529 tls_modify_variables(&tls_out);
1530
1531 #ifndef SUPPORT_TLS
1532 if (sx->smtps)
1533 {
1534 set_errno_nohost(sx->addrlist, ERRNO_TLSFAILURE, US"TLS support not available",
1535 DEFER, FALSE);
1536 return ERROR;
1537 }
1538 #endif
1539
1540 /* Make a connection to the host if this isn't a continued delivery, and handle
1541 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
1542 specially so they can be identified for retries. */
1543
1544 if (continue_hostname == NULL)
1545 {
1546 if (sx->verify)
1547 HDEBUG(D_verify) debug_printf("interface=%s port=%d\n", sx->interface, sx->port);
1548
1549 /* This puts port into host->port */
1550 sx->inblock.sock = sx->outblock.sock =
1551 smtp_connect(sx->host, sx->host_af, sx->port, sx->interface,
1552 sx->ob->connect_timeout, sx->tblock);
1553
1554 if (sx->inblock.sock < 0)
1555 {
1556 uschar * msg = NULL;
1557 if (sx->verify)
1558 {
1559 msg = US strerror(errno);
1560 HDEBUG(D_verify) debug_printf("connect: %s\n", msg);
1561 }
1562 set_errno_nohost(sx->addrlist,
1563 errno == ETIMEDOUT ? ERRNO_CONNECTTIMEOUT : errno,
1564 sx->verify ? string_sprintf("could not connect: %s", msg)
1565 : NULL,
1566 DEFER, FALSE);
1567 sx->send_quit = FALSE;
1568 return DEFER;
1569 }
1570
1571 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1572 {
1573 tls_out.dane_verified = FALSE;
1574 tls_out.tlsa_usage = 0;
1575
1576 if (sx->host->dnssec == DS_YES)
1577 {
1578 if( sx->dane_required
1579 || verify_check_given_host(&sx->ob->hosts_try_dane, sx->host) == OK
1580 )
1581 switch (rc = tlsa_lookup(sx->host, &tlsa_dnsa, sx->dane_required))
1582 {
1583 case OK: sx->dane = TRUE; break;
1584 case FAIL_FORCED: break;
1585 default: set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
1586 string_sprintf("DANE error: tlsa lookup %s",
1587 rc == DEFER ? "DEFER" : "FAIL"),
1588 rc, FALSE);
1589 return rc;
1590 }
1591 }
1592 else if (sx->dane_required)
1593 {
1594 set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
1595 string_sprintf("DANE error: %s lookup not DNSSEC", sx->host->name),
1596 FAIL, FALSE);
1597 return FAIL;
1598 }
1599
1600 if (sx->dane)
1601 sx->ob->tls_tempfail_tryclear = FALSE;
1602 }
1603 #endif /*DANE*/
1604
1605 /* Expand the greeting message while waiting for the initial response. (Makes
1606 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1607 delayed till here so that $sending_interface and $sending_port are set. */
1608
1609 if (sx->helo_data)
1610 if (!(sx->helo_data = expand_string(sx->helo_data)))
1611 if (sx->verify)
1612 log_write(0, LOG_MAIN|LOG_PANIC,
1613 "<%s>: failed to expand transport's helo_data value for callout: %s",
1614 sx->addrlist->address, expand_string_message);
1615
1616 #ifdef SUPPORT_I18N
1617 if (sx->helo_data)
1618 {
1619 expand_string_message = NULL;
1620 if ((sx->helo_data = string_domain_utf8_to_alabel(sx->helo_data,
1621 &expand_string_message)),
1622 expand_string_message)
1623 if (sx->verify)
1624 log_write(0, LOG_MAIN|LOG_PANIC,
1625 "<%s>: failed to expand transport's helo_data value for callout: %s",
1626 sx->addrlist->address, expand_string_message);
1627 else
1628 sx->helo_data = NULL;
1629 }
1630 #endif
1631
1632 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1633 is nevertheless a reasonably clean way of programming this kind of logic,
1634 where you want to escape on any error. */
1635
1636 if (!sx->smtps)
1637 {
1638 BOOL good_response;
1639
1640 #ifdef TCP_QUICKACK
1641 (void) setsockopt(sx->inblock.sock, IPPROTO_TCP, TCP_QUICKACK, US &off, sizeof(off));
1642 #endif
1643 good_response = smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
1644 '2', sx->ob->command_timeout);
1645 #ifdef EXPERIMENTAL_DSN_INFO
1646 sx->smtp_greeting = string_copy(sx->buffer);
1647 #endif
1648 if (!good_response) goto RESPONSE_FAILED;
1649
1650 #ifndef DISABLE_EVENT
1651 {
1652 uschar * s;
1653 lookup_dnssec_authenticated = sx->host->dnssec==DS_YES ? US"yes"
1654 : sx->host->dnssec==DS_NO ? US"no" : NULL;
1655 s = event_raise(sx->tblock->event_action, US"smtp:connect", sx->buffer);
1656 if (s)
1657 {
1658 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL,
1659 string_sprintf("deferred by smtp:connect event expansion: %s", s),
1660 DEFER, FALSE);
1661 yield = DEFER;
1662 goto SEND_QUIT;
1663 }
1664 }
1665 #endif
1666
1667 /* Now check if the helo_data expansion went well, and sign off cleanly if
1668 it didn't. */
1669
1670 if (!sx->helo_data)
1671 {
1672 message = string_sprintf("failed to expand helo_data: %s",
1673 expand_string_message);
1674 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1675 yield = DEFER;
1676 goto SEND_QUIT;
1677 }
1678 }
1679
1680 /** Debugging without sending a message
1681 sx->addrlist->transport_return = DEFER;
1682 goto SEND_QUIT;
1683 **/
1684
1685 /* Errors that occur after this point follow an SMTP command, which is
1686 left in big_buffer by smtp_write_command() for use in error messages. */
1687
1688 smtp_command = big_buffer;
1689
1690 /* Tell the remote who we are...
1691
1692 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1693 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1694 greeting is of this form. The assumption was that the far end supports it
1695 properly... but experience shows that there are some that give 5xx responses,
1696 even though the banner includes "ESMTP" (there's a bloody-minded one that
1697 says "ESMTP not spoken here"). Cope with that case.
1698
1699 September 2000: Time has passed, and it seems reasonable now to always send
1700 EHLO at the start. It is also convenient to make the change while installing
1701 the TLS stuff.
1702
1703 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1704 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1705 would be no way to send out the mails, so there is now a host list
1706 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1707 PIPELINING problem as well. Maybe it can also be useful to cure other
1708 problems with broken servers.
1709
1710 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1711 Then somebody tried it with a Microsoft mailer... It seems that all other
1712 mailers use upper case for some reason (the RFC is quite clear about case
1713 independence) so, for peace of mind, I gave in. */
1714
1715 sx->esmtp = verify_check_given_host(&sx->ob->hosts_avoid_esmtp, sx->host) != OK;
1716
1717 /* Alas; be careful, since this goto is not an error-out, so conceivably
1718 we might set data between here and the target which we assume to exist
1719 and be usable. I can see this coming back to bite us. */
1720 #ifdef SUPPORT_TLS
1721 if (sx->smtps)
1722 {
1723 smtp_peer_options |= PEER_OFFERED_TLS;
1724 suppress_tls = FALSE;
1725 sx->ob->tls_tempfail_tryclear = FALSE;
1726 smtp_command = US"SSL-on-connect";
1727 goto TLS_NEGOTIATE;
1728 }
1729 #endif
1730
1731 if (sx->esmtp)
1732 {
1733 if (smtp_write_command(&sx->outblock, FALSE, "%s %s\r\n",
1734 sx->lmtp ? "LHLO" : "EHLO", sx->helo_data) < 0)
1735 goto SEND_FAILED;
1736 sx->esmtp_sent = TRUE;
1737 if (!smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer), '2',
1738 sx->ob->command_timeout))
1739 {
1740 if (errno != 0 || sx->buffer[0] == 0 || sx->lmtp)
1741 {
1742 #ifdef EXPERIMENTAL_DSN_INFO
1743 sx->helo_response = string_copy(sx->buffer);
1744 #endif
1745 goto RESPONSE_FAILED;
1746 }
1747 sx->esmtp = FALSE;
1748 }
1749 #ifdef EXPERIMENTAL_DSN_INFO
1750 sx->helo_response = string_copy(sx->buffer);
1751 #endif
1752 }
1753 else
1754 DEBUG(D_transport)
1755 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1756
1757 if (!sx->esmtp)
1758 {
1759 BOOL good_response;
1760 int n = sizeof(sx->buffer);
1761 uschar * rsp = sx->buffer;
1762
1763 if (sx->esmtp_sent && (n = Ustrlen(sx->buffer)) < sizeof(sx->buffer)/2)
1764 { rsp = sx->buffer + n + 1; n = sizeof(sx->buffer) - n; }
1765
1766 if (smtp_write_command(&sx->outblock, FALSE, "HELO %s\r\n", sx->helo_data) < 0)
1767 goto SEND_FAILED;
1768 good_response = smtp_read_response(&sx->inblock, rsp, n,
1769 '2', sx->ob->command_timeout);
1770 #ifdef EXPERIMENTAL_DSN_INFO
1771 sx->helo_response = string_copy(rsp);
1772 #endif
1773 if (!good_response)
1774 {
1775 /* Handle special logging for a closed connection after HELO
1776 when had previously sent EHLO */
1777
1778 if (rsp != sx->buffer && rsp[0] == 0 && (errno == 0 || errno == ECONNRESET))
1779 {
1780 errno = ERRNO_SMTPCLOSED;
1781 goto EHLOHELO_FAILED;
1782 }
1783 Ustrncpy(sx->buffer, rsp, sizeof(sx->buffer)/2);
1784 goto RESPONSE_FAILED;
1785 }
1786 }
1787
1788 sx->peer_offered = smtp_peer_options = 0;
1789
1790 if (sx->esmtp || sx->lmtp)
1791 {
1792 sx->peer_offered = ehlo_response(sx->buffer,
1793 PEER_OFFERED_TLS /* others checked later */
1794 );
1795
1796 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1797
1798 #ifdef SUPPORT_TLS
1799 smtp_peer_options |= sx->peer_offered & PEER_OFFERED_TLS;
1800 #endif
1801 }
1802 }
1803
1804 /* For continuing deliveries down the same channel, the socket is the standard
1805 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1806 below). Set up the pointer to where subsequent commands will be left, for
1807 error messages. Note that smtp_peer_options will have been
1808 set from the command line if they were set in the process that passed the
1809 connection on. */
1810
1811 /*XXX continue case needs to propagate DSN_INFO, prob. in deliver.c
1812 as the continue goes via transport_pass_socket() and doublefork and exec.
1813 It does not wait. Unclear how we keep separate host's responses
1814 separate - we could match up by host ip+port as a bodge. */
1815
1816 else
1817 {
1818 sx->inblock.sock = sx->outblock.sock = 0; /* stdin */
1819 smtp_command = big_buffer;
1820 sx->host->port = sx->port; /* Record the port that was used */
1821 sx->helo_data = NULL; /* ensure we re-expand ob->helo_data */
1822
1823 /* For a continued connection with TLS being proxied for us, nothing
1824 more to do. */
1825
1826 if (continue_proxy)
1827 {
1828 sx->peer_offered = smtp_peer_options;
1829 pipelining_active = !!(smtp_peer_options & PEER_OFFERED_PIPE);
1830 HDEBUG(D_transport) debug_printf("continued connection, proxied TLS\n");
1831 return OK;
1832 }
1833 HDEBUG(D_transport) debug_printf("continued connection, no TLS\n");
1834 }
1835
1836 /* If TLS is available on this connection, whether continued or not, attempt to
1837 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1838 send another EHLO - the server may give a different answer in secure mode. We
1839 use a separate buffer for reading the response to STARTTLS so that if it is
1840 negative, the original EHLO data is available for subsequent analysis, should
1841 the client not be required to use TLS. If the response is bad, copy the buffer
1842 for error analysis. */
1843
1844 #ifdef SUPPORT_TLS
1845 if ( smtp_peer_options & PEER_OFFERED_TLS
1846 && !suppress_tls
1847 && verify_check_given_host(&sx->ob->hosts_avoid_tls, sx->host) != OK
1848 && ( !sx->verify
1849 || verify_check_given_host(&sx->ob->hosts_verify_avoid_tls, sx->host) != OK
1850 ) )
1851 {
1852 uschar buffer2[4096];
1853 if (smtp_write_command(&sx->outblock, FALSE, "STARTTLS\r\n") < 0)
1854 goto SEND_FAILED;
1855
1856 /* If there is an I/O error, transmission of this message is deferred. If
1857 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1858 false, we also defer. However, if there is a temporary rejection of STARTTLS
1859 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1860 STARTTLS, we carry on. This means we will try to send the message in clear,
1861 unless the host is in hosts_require_tls (tested below). */
1862
1863 if (!smtp_read_response(&sx->inblock, buffer2, sizeof(buffer2), '2',
1864 sx->ob->command_timeout))
1865 {
1866 if ( errno != 0
1867 || buffer2[0] == 0
1868 || (buffer2[0] == '4' && !sx->ob->tls_tempfail_tryclear)
1869 )
1870 {
1871 Ustrncpy(sx->buffer, buffer2, sizeof(sx->buffer));
1872 sx->buffer[sizeof(sx->buffer)-1] = '\0';
1873 goto RESPONSE_FAILED;
1874 }
1875 }
1876
1877 /* STARTTLS accepted: try to negotiate a TLS session. */
1878
1879 else
1880 TLS_NEGOTIATE:
1881 {
1882 address_item * addr;
1883 uschar * errstr;
1884 int rc = tls_client_start(sx->inblock.sock, sx->host, sx->addrlist, sx->tblock,
1885 # ifdef EXPERIMENTAL_DANE
1886 sx->dane ? &tlsa_dnsa : NULL,
1887 # endif
1888 &errstr);
1889
1890 /* TLS negotiation failed; give an error. From outside, this function may
1891 be called again to try in clear on a new connection, if the options permit
1892 it for this host. */
1893
1894 if (rc != OK)
1895 {
1896 # ifdef EXPERIMENTAL_DANE
1897 if (sx->dane) log_write(0, LOG_MAIN,
1898 "DANE attempt failed; TLS connection to %s [%s]: %s",
1899 sx->host->name, sx->host->address, errstr);
1900 # endif
1901
1902 errno = ERRNO_TLSFAILURE;
1903 message = string_sprintf("TLS session: %s", errstr);
1904 sx->send_quit = FALSE;
1905 goto TLS_FAILED;
1906 }
1907
1908 /* TLS session is set up */
1909
1910 smtp_peer_options_wrap = smtp_peer_options;
1911 for (addr = sx->addrlist; addr; addr = addr->next)
1912 if (addr->transport_return == PENDING_DEFER)
1913 {
1914 addr->cipher = tls_out.cipher;
1915 addr->ourcert = tls_out.ourcert;
1916 addr->peercert = tls_out.peercert;
1917 addr->peerdn = tls_out.peerdn;
1918 addr->ocsp = tls_out.ocsp;
1919 }
1920 }
1921 }
1922
1923 /* if smtps, we'll have smtp_command set to something else; always safe to
1924 reset it here. */
1925 smtp_command = big_buffer;
1926
1927 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1928 helo_data is null, we are dealing with a connection that was passed from
1929 another process, and so we won't have expanded helo_data above. We have to
1930 expand it here. $sending_ip_address and $sending_port are set up right at the
1931 start of the Exim process (in exim.c). */
1932
1933 if (tls_out.active >= 0)
1934 {
1935 char *greeting_cmd;
1936 BOOL good_response;
1937
1938 if (!sx->helo_data && !(sx->helo_data = expand_string(sx->ob->helo_data)))
1939 {
1940 uschar *message = string_sprintf("failed to expand helo_data: %s",
1941 expand_string_message);
1942 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1943 yield = DEFER;
1944 goto SEND_QUIT;
1945 }
1946
1947 /* For SMTPS we need to wait for the initial OK response. */
1948 if (sx->smtps)
1949 {
1950 good_response = smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
1951 '2', sx->ob->command_timeout);
1952 #ifdef EXPERIMENTAL_DSN_INFO
1953 sx->smtp_greeting = string_copy(sx->buffer);
1954 #endif
1955 if (!good_response) goto RESPONSE_FAILED;
1956 }
1957
1958 if (sx->esmtp)
1959 greeting_cmd = "EHLO";
1960 else
1961 {
1962 greeting_cmd = "HELO";
1963 DEBUG(D_transport)
1964 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1965 }
1966
1967 if (smtp_write_command(&sx->outblock, FALSE, "%s %s\r\n",
1968 sx->lmtp ? "LHLO" : greeting_cmd, sx->helo_data) < 0)
1969 goto SEND_FAILED;
1970 good_response = smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
1971 '2', sx->ob->command_timeout);
1972 #ifdef EXPERIMENTAL_DSN_INFO
1973 sx->helo_response = string_copy(sx->buffer);
1974 #endif
1975 if (!good_response) goto RESPONSE_FAILED;
1976 smtp_peer_options = 0;
1977 }
1978
1979 /* If the host is required to use a secure channel, ensure that we
1980 have one. */
1981
1982 else if ( sx->smtps
1983 # ifdef EXPERIMENTAL_DANE
1984 || sx->dane
1985 # endif
1986 || verify_check_given_host(&sx->ob->hosts_require_tls, sx->host) == OK
1987 )
1988 {
1989 errno = ERRNO_TLSREQUIRED;
1990 message = string_sprintf("a TLS session is required, but %s",
1991 smtp_peer_options & PEER_OFFERED_TLS
1992 ? "an attempt to start TLS failed" : "the server did not offer TLS support");
1993 goto TLS_FAILED;
1994 }
1995 #endif /*SUPPORT_TLS*/
1996
1997 /* If TLS is active, we have just started it up and re-done the EHLO command,
1998 so its response needs to be analyzed. If TLS is not active and this is a
1999 continued session down a previously-used socket, we haven't just done EHLO, so
2000 we skip this. */
2001
2002 if (continue_hostname == NULL
2003 #ifdef SUPPORT_TLS
2004 || tls_out.active >= 0
2005 #endif
2006 )
2007 {
2008 if (sx->esmtp || sx->lmtp)
2009 {
2010 sx->peer_offered = ehlo_response(sx->buffer,
2011 0 /* no TLS */
2012 | (sx->lmtp && sx->ob->lmtp_ignore_quota ? PEER_OFFERED_IGNQ : 0)
2013 | PEER_OFFERED_CHUNKING
2014 | PEER_OFFERED_PRDR
2015 #ifdef SUPPORT_I18N
2016 | (sx->addrlist->prop.utf8_msg ? PEER_OFFERED_UTF8 : 0)
2017 /*XXX if we hand peercaps on to continued-conn processes,
2018 must not depend on this addr */
2019 #endif
2020 | PEER_OFFERED_DSN
2021 | PEER_OFFERED_PIPE
2022 | (sx->ob->size_addition >= 0 ? PEER_OFFERED_SIZE : 0)
2023 );
2024
2025 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
2026 lmtp_ignore_quota option was set. */
2027
2028 sx->igquotstr = sx->peer_offered & PEER_OFFERED_IGNQ ? US" IGNOREQUOTA" : US"";
2029
2030 /* If the response to EHLO specified support for the SIZE parameter, note
2031 this, provided size_addition is non-negative. */
2032
2033 smtp_peer_options |= sx->peer_offered & PEER_OFFERED_SIZE;
2034
2035 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
2036 the current host, esmtp will be false, so PIPELINING can never be used. If
2037 the current host matches hosts_avoid_pipelining, don't do it. */
2038
2039 if ( sx->peer_offered & PEER_OFFERED_PIPE
2040 && verify_check_given_host(&sx->ob->hosts_avoid_pipelining, sx->host) != OK)
2041 smtp_peer_options |= PEER_OFFERED_PIPE;
2042
2043 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
2044 smtp_peer_options & PEER_OFFERED_PIPE ? "" : "not ");
2045
2046 if ( sx->peer_offered & PEER_OFFERED_CHUNKING
2047 && verify_check_given_host(&sx->ob->hosts_try_chunking, sx->host) != OK)
2048 sx->peer_offered &= ~PEER_OFFERED_CHUNKING;
2049
2050 if (sx->peer_offered & PEER_OFFERED_CHUNKING)
2051 {DEBUG(D_transport) debug_printf("CHUNKING usable\n");}
2052
2053 #ifndef DISABLE_PRDR
2054 if ( sx->peer_offered & PEER_OFFERED_PRDR
2055 && verify_check_given_host(&sx->ob->hosts_try_prdr, sx->host) != OK)
2056 sx->peer_offered &= ~PEER_OFFERED_PRDR;
2057
2058 if (sx->peer_offered & PEER_OFFERED_PRDR)
2059 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
2060 #endif
2061
2062 /* Note if the server supports DSN */
2063 smtp_peer_options |= sx->peer_offered & PEER_OFFERED_DSN;
2064 DEBUG(D_transport) debug_printf("%susing DSN\n",
2065 sx->peer_offered & PEER_OFFERED_DSN ? "" : "not ");
2066
2067 /* Note if the response to EHLO specifies support for the AUTH extension.
2068 If it has, check that this host is one we want to authenticate to, and do
2069 the business. The host name and address must be available when the
2070 authenticator's client driver is running. */
2071
2072 switch (yield = smtp_auth(sx->buffer, sizeof(sx->buffer), sx->addrlist, sx->host,
2073 sx->ob, sx->esmtp, &sx->inblock, &sx->outblock))
2074 {
2075 default: goto SEND_QUIT;
2076 case OK: break;
2077 case FAIL_SEND: goto SEND_FAILED;
2078 case FAIL: goto RESPONSE_FAILED;
2079 }
2080 }
2081 }
2082 pipelining_active = !!(smtp_peer_options & PEER_OFFERED_PIPE);
2083
2084 /* The setting up of the SMTP call is now complete. Any subsequent errors are
2085 message-specific. */
2086
2087 sx->setting_up = FALSE;
2088
2089 #ifdef SUPPORT_I18N
2090 if (sx->addrlist->prop.utf8_msg)
2091 {
2092 sx->utf8_needed = !sx->addrlist->prop.utf8_downcvt
2093 && !sx->addrlist->prop.utf8_downcvt_maybe;
2094 DEBUG(D_transport) if (!sx->utf8_needed)
2095 debug_printf("utf8: %s downconvert\n",
2096 sx->addrlist->prop.utf8_downcvt ? "mandatory" : "optional");
2097 }
2098
2099 /* If this is an international message we need the host to speak SMTPUTF8 */
2100 if (sx->utf8_needed && !(sx->peer_offered & PEER_OFFERED_UTF8))
2101 {
2102 errno = ERRNO_UTF8_FWD;
2103 goto RESPONSE_FAILED;
2104 }
2105 #endif
2106
2107 return OK;
2108
2109
2110 {
2111 int code;
2112
2113 RESPONSE_FAILED:
2114 message = NULL;
2115 sx->send_quit = check_response(sx->host, &errno, sx->addrlist->more_errno,
2116 sx->buffer, &code, &message, &pass_message);
2117 goto FAILED;
2118
2119 SEND_FAILED:
2120 code = '4';
2121 message = US string_sprintf("send() to %s [%s] failed: %s",
2122 sx->host->name, sx->host->address, strerror(errno));
2123 sx->send_quit = FALSE;
2124 goto FAILED;
2125
2126 /* This label is jumped to directly when a TLS negotiation has failed,
2127 or was not done for a host for which it is required. Values will be set
2128 in message and errno, and setting_up will always be true. Treat as
2129 a temporary error. */
2130
2131 EHLOHELO_FAILED:
2132 code = '4';
2133 message = string_sprintf("Remote host closed connection in response to %s"
2134 " (EHLO response was: %s)", smtp_command, sx->buffer);
2135 sx->send_quit = FALSE;
2136 goto FAILED;
2137
2138 #ifdef SUPPORT_TLS
2139 TLS_FAILED:
2140 code = '4';
2141 goto FAILED;
2142 #endif
2143
2144 /* The failure happened while setting up the call; see if the failure was
2145 a 5xx response (this will either be on connection, or following HELO - a 5xx
2146 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
2147 never going to accept them. For other errors during setting up (timeouts or
2148 whatever), defer all addresses, and yield DEFER, so that the host is not
2149 tried again for a while. */
2150
2151 FAILED:
2152 sx->ok = FALSE; /* For when reached by GOTO */
2153
2154 yield = code == '5'
2155 #ifdef SUPPORT_I18N
2156 || errno == ERRNO_UTF8_FWD
2157 #endif
2158 ? FAIL : DEFER;
2159
2160 set_errno(sx->addrlist, errno, message, yield, pass_message, sx->host
2161 #ifdef EXPERIMENTAL_DSN_INFO
2162 , sx->smtp_greeting, sx->helo_response
2163 #endif
2164 );
2165 }
2166
2167
2168 SEND_QUIT:
2169
2170 if (sx->send_quit)
2171 (void)smtp_write_command(&sx->outblock, FALSE, "QUIT\r\n");
2172
2173 #ifdef SUPPORT_TLS
2174 tls_close(FALSE, TRUE);
2175 #endif
2176
2177 /* Close the socket, and return the appropriate value, first setting
2178 works because the NULL setting is passed back to the calling process, and
2179 remote_max_parallel is forced to 1 when delivering over an existing connection,
2180
2181 If all went well and continue_more is set, we shouldn't actually get here if
2182 there are further addresses, as the return above will be taken. However,
2183 writing RSET might have failed, or there may be other addresses whose hosts are
2184 specified in the transports, and therefore not visible at top level, in which
2185 case continue_more won't get set. */
2186
2187 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
2188 if (sx->send_quit)
2189 {
2190 shutdown(sx->outblock.sock, SHUT_WR);
2191 if (fcntl(sx->inblock.sock, F_SETFL, O_NONBLOCK) == 0)
2192 for (rc = 16; read(sx->inblock.sock, sx->inbuffer, sizeof(sx->inbuffer)) > 0 && rc > 0;)
2193 rc--; /* drain socket */
2194 sx->send_quit = FALSE;
2195 }
2196 (void)close(sx->inblock.sock);
2197 sx->inblock.sock = sx->outblock.sock = -1;
2198
2199 #ifndef DISABLE_EVENT
2200 (void) event_raise(sx->tblock->event_action, US"tcp:close", NULL);
2201 #endif
2202
2203 continue_transport = NULL;
2204 continue_hostname = NULL;
2205 return yield;
2206 }
2207
2208
2209
2210
2211 /* Create the string of options that will be appended to the MAIL FROM:
2212 in the connection context buffer */
2213
2214 static int
2215 build_mailcmd_options(smtp_context * sx, address_item * addrlist)
2216 {
2217 uschar * p = sx->buffer;
2218 address_item * addr;
2219 int address_count;
2220
2221 *p = 0;
2222
2223 /* If we know the receiving MTA supports the SIZE qualification,
2224 send it, adding something to the message size to allow for imprecision
2225 and things that get added en route. Exim keeps the number of lines
2226 in a message, so we can give an accurate value for the original message, but we
2227 need some additional to handle added headers. (Double "." characters don't get
2228 included in the count.) */
2229
2230 if (sx->peer_offered & PEER_OFFERED_SIZE)
2231 {
2232 sprintf(CS p, " SIZE=%d", message_size+message_linecount+sx->ob->size_addition);
2233 while (*p) p++;
2234 }
2235
2236 #ifndef DISABLE_PRDR
2237 /* If it supports Per-Recipient Data Reponses, and we have omre than one recipient,
2238 request that */
2239
2240 sx->prdr_active = FALSE;
2241 if (sx->peer_offered & PEER_OFFERED_PRDR)
2242 for (addr = addrlist; addr; addr = addr->next)
2243 if (addr->transport_return == PENDING_DEFER)
2244 {
2245 for (addr = addr->next; addr; addr = addr->next)
2246 if (addr->transport_return == PENDING_DEFER)
2247 { /* at least two recipients to send */
2248 sx->prdr_active = TRUE;
2249 sprintf(CS p, " PRDR"); p += 5;
2250 break;
2251 }
2252 break;
2253 }
2254 #endif
2255
2256 #ifdef SUPPORT_I18N
2257 /* If it supports internationalised messages, and this meesage need that,
2258 request it */
2259
2260 if ( sx->peer_offered & PEER_OFFERED_UTF8
2261 && addrlist->prop.utf8_msg
2262 && !addrlist->prop.utf8_downcvt
2263 )
2264 Ustrcpy(p, " SMTPUTF8"), p += 9;
2265 #endif
2266
2267 /* check if all addresses have DSN-lasthop flag; do not send RET and ENVID if so */
2268 for (sx->dsn_all_lasthop = TRUE, addr = addrlist, address_count = 0;
2269 addr && address_count < sx->max_rcpt;
2270 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
2271 {
2272 address_count++;
2273 if (!(addr->dsn_flags & rf_dsnlasthop))
2274 {
2275 sx->dsn_all_lasthop = FALSE;
2276 break;
2277 }
2278 }
2279
2280 /* Add any DSN flags to the mail command */
2281
2282 if (sx->peer_offered & PEER_OFFERED_DSN && !sx->dsn_all_lasthop)
2283 {
2284 if (dsn_ret == dsn_ret_hdrs)
2285 { Ustrcpy(p, " RET=HDRS"); p += 9; }
2286 else if (dsn_ret == dsn_ret_full)
2287 { Ustrcpy(p, " RET=FULL"); p += 9; }
2288
2289 if (dsn_envid)
2290 {
2291 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ENVID=%s", dsn_envid);
2292 while (*p) p++;
2293 }
2294 }
2295
2296 /* If an authenticated_sender override has been specified for this transport
2297 instance, expand it. If the expansion is forced to fail, and there was already
2298 an authenticated_sender for this message, the original value will be used.
2299 Other expansion failures are serious. An empty result is ignored, but there is
2300 otherwise no check - this feature is expected to be used with LMTP and other
2301 cases where non-standard addresses (e.g. without domains) might be required. */
2302
2303 if (smtp_mail_auth_str(p, sizeof(sx->buffer) - (p-sx->buffer), addrlist, sx->ob))
2304 return ERROR;
2305
2306 return OK;
2307 }
2308
2309
2310 static void
2311 build_rcptcmd_options(smtp_context * sx, const address_item * addr)
2312 {
2313 uschar * p = sx->buffer;
2314 *p = 0;
2315
2316 /* Add any DSN flags to the rcpt command */
2317
2318 if (sx->peer_offered & PEER_OFFERED_DSN && !(addr->dsn_flags & rf_dsnlasthop))
2319 {
2320 if (addr->dsn_flags & rf_dsnflags)
2321 {
2322 int i;
2323 BOOL first = TRUE;
2324
2325 Ustrcpy(p, " NOTIFY=");
2326 while (*p) p++;
2327 for (i = 0; i < nelem(rf_list); i++) if (addr->dsn_flags & rf_list[i])
2328 {
2329 if (!first) *p++ = ',';
2330 first = FALSE;
2331 Ustrcpy(p, rf_names[i]);
2332 while (*p) p++;
2333 }
2334 }
2335
2336 if (addr->dsn_orcpt)
2337 {
2338 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ORCPT=%s",
2339 addr->dsn_orcpt);
2340 while (*p) p++;
2341 }
2342 }
2343 }
2344
2345
2346
2347 /*
2348 Return:
2349 0 good, rcpt results in addr->transport_return (PENDING_OK, DEFER, FAIL)
2350 -1 MAIL response error
2351 -2 any non-MAIL read i/o error
2352 -3 non-MAIL response timeout
2353 -4 internal error; channel still usable
2354 -5 transmit failed
2355 */
2356
2357 int
2358 smtp_write_mail_and_rcpt_cmds(smtp_context * sx, int * yield)
2359 {
2360 address_item * addr;
2361 int address_count;
2362 int rc;
2363
2364 if (build_mailcmd_options(sx, sx->first_addr) != OK)
2365 {
2366 *yield = ERROR;
2367 return -4;
2368 }
2369
2370 /* From here until we send the DATA command, we can make use of PIPELINING
2371 if the server host supports it. The code has to be able to check the responses
2372 at any point, for when the buffer fills up, so we write it totally generally.
2373 When PIPELINING is off, each command written reports that it has flushed the
2374 buffer. */
2375
2376 sx->pending_MAIL = TRUE; /* The block starts with MAIL */
2377
2378 {
2379 uschar * s = sx->from_addr;
2380 #ifdef SUPPORT_I18N
2381 uschar * errstr = NULL;
2382
2383 /* If we must downconvert, do the from-address here. Remember we had to
2384 for the to-addresses (done below), and also (ugly) for re-doing when building
2385 the delivery log line. */
2386
2387 if ( sx->addrlist->prop.utf8_msg
2388 && (sx->addrlist->prop.utf8_downcvt || !(sx->peer_offered & PEER_OFFERED_UTF8))
2389 )
2390 {
2391 if (s = string_address_utf8_to_alabel(s, &errstr), errstr)
2392 {
2393 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE);
2394 *yield = ERROR;
2395 return -4;
2396 }
2397 setflag(sx->addrlist, af_utf8_downcvt);
2398 }
2399 #endif
2400
2401 rc = smtp_write_command(&sx->outblock, pipelining_active,
2402 "MAIL FROM:<%s>%s\r\n", s, sx->buffer);
2403 }
2404
2405 mail_command = string_copy(big_buffer); /* Save for later error message */
2406
2407 switch(rc)
2408 {
2409 case -1: /* Transmission error */
2410 return -5;
2411
2412 case +1: /* Cmd was sent */
2413 if (!smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer), '2',
2414 sx->ob->command_timeout))
2415 {
2416 if (errno == 0 && sx->buffer[0] == '4')
2417 {
2418 errno = ERRNO_MAIL4XX;
2419 sx->addrlist->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
2420 }
2421 return -1;
2422 }
2423 sx->pending_MAIL = FALSE;
2424 break;
2425
2426 /* otherwise zero: command queued for pipeline */
2427 }
2428
2429 /* Pass over all the relevant recipient addresses for this host, which are the
2430 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
2431 several before we have to read the responses for those seen so far. This
2432 checking is done by a subroutine because it also needs to be done at the end.
2433 Send only up to max_rcpt addresses at a time, leaving next_addr pointing to
2434 the next one if not all are sent.
2435
2436 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
2437 last address because we want to abort if any recipients have any kind of
2438 problem, temporary or permanent. We know that all recipient addresses will have
2439 the PENDING_DEFER status, because only one attempt is ever made, and we know
2440 that max_rcpt will be large, so all addresses will be done at once.
2441
2442 For verify we flush the pipeline after any (the only) rcpt address. */
2443
2444 for (addr = sx->first_addr, address_count = 0;
2445 addr && address_count < sx->max_rcpt;
2446 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
2447 {
2448 int count;
2449 BOOL no_flush;
2450 uschar * rcpt_addr;
2451
2452 addr->dsn_aware = sx->peer_offered & PEER_OFFERED_DSN
2453 ? dsn_support_yes : dsn_support_no;
2454
2455 address_count++;
2456 no_flush = pipelining_active && !sx->verify && (!mua_wrapper || addr->next);
2457
2458 build_rcptcmd_options(sx, addr);
2459
2460 /* Now send the RCPT command, and process outstanding responses when
2461 necessary. After a timeout on RCPT, we just end the function, leaving the
2462 yield as OK, because this error can often mean that there is a problem with
2463 just one address, so we don't want to delay the host. */
2464
2465 rcpt_addr = transport_rcpt_address(addr, sx->tblock->rcpt_include_affixes);
2466
2467 #ifdef SUPPORT_I18N
2468 if ( testflag(sx->addrlist, af_utf8_downcvt)
2469 && !(rcpt_addr = string_address_utf8_to_alabel(rcpt_addr, NULL))
2470 )
2471 {
2472 /*XXX could we use a per-address errstr here? Not fail the whole send? */
2473 errno = ERRNO_EXPANDFAIL;
2474 return -5; /*XXX too harsh? */
2475 }
2476 #endif
2477
2478 count = smtp_write_command(&sx->outblock, no_flush, "RCPT TO:<%s>%s%s\r\n",
2479 rcpt_addr, sx->igquotstr, sx->buffer);
2480
2481 if (count < 0) return -5;
2482 if (count > 0)
2483 {
2484 switch(sync_responses(sx, count, 0))
2485 {
2486 case 3: sx->ok = TRUE; /* 2xx & 5xx => OK & progress made */
2487 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
2488 break;
2489
2490 case 1: sx->ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2491 if (!sx->lmtp) /* can't tell about progress yet */
2492 sx->completed_addr = TRUE;
2493 case 0: /* No 2xx or 5xx, but no probs */
2494 break;
2495
2496 case -1: return -3; /* Timeout on RCPT */
2497 case -2: return -2; /* non-MAIL read i/o error */
2498 default: return -1; /* any MAIL error */
2499 }
2500 sx->pending_MAIL = FALSE; /* Dealt with MAIL */
2501 }
2502 } /* Loop for next address */
2503
2504 sx->next_addr = addr;
2505 return 0;
2506 }
2507
2508
2509 #ifdef SUPPORT_TLS
2510 /*****************************************************
2511 * Proxy TLS connection for another transport process *
2512 ******************************************************/
2513 /*
2514 Use the smtp-context buffer as a staging area, and select on both the slave
2515 process and the TLS'd fd for data to read (per the coding in ip_recv() and
2516 fd_ready() this is legitimate). Do blocking full-size writes, and reads
2517 under a timeout.
2518
2519 Arguments:
2520 sx smtp context block
2521 proxy_fd comms to proxied process
2522 timeout per-read timeout, seconds
2523 */
2524
2525 static void
2526 smtp_proxy_tls(smtp_context * sx, int proxy_fd, int timeout)
2527 {
2528 fd_set fds;
2529 int max_fd = MAX(proxy_fd, tls_out.active) + 1;
2530 int rc, i, fd_bits, nbytes;
2531
2532 set_process_info("proxying TLS connection for continued transport");
2533 FD_ZERO(&fds);
2534 FD_SET(tls_out.active, &fds);
2535 FD_SET(proxy_fd, &fds);
2536
2537 for (fd_bits = 3; fd_bits; )
2538 {
2539 time_t time_left = timeout;
2540 time_t time_start = time(NULL);
2541
2542 /* wait for data */
2543 do
2544 {
2545 struct timeval tv = { time_left, 0 };
2546
2547 rc = select(max_fd, (SELECT_ARG2_TYPE *)&fds, NULL, NULL, &tv);
2548
2549 if (rc < 0 && errno == EINTR)
2550 if ((time_left -= time(NULL) - time_start) > 0) continue;
2551
2552 if (rc <= 0)
2553 {
2554 DEBUG(D_transport) if (rc == 0) debug_printf("%s: timed out\n", __FUNCTION__);
2555 return;
2556 }
2557 }
2558 while (rc < 0 || !(FD_ISSET(tls_out.active, &fds) || FD_ISSET(proxy_fd, &fds)));
2559
2560 /* handle inbound data */
2561 if (FD_ISSET(tls_out.active, &fds))
2562 if ((rc = tls_read(FALSE, sx->buffer, sizeof(sx->buffer))) <= 0)
2563 {
2564 fd_bits &= ~1;
2565 FD_CLR(tls_out.active, &fds);
2566 shutdown(proxy_fd, SHUT_WR);
2567 }
2568 else
2569 {
2570 for (nbytes = 0; rc - nbytes > 0; nbytes += i)
2571 if ((i = write(proxy_fd, sx->buffer + nbytes, rc - nbytes)) < 0) return;
2572 }
2573 else if (fd_bits & 1)
2574 FD_SET(tls_out.active, &fds);
2575
2576 /* handle outbound data */
2577 if (FD_ISSET(proxy_fd, &fds))
2578 if ((rc = read(proxy_fd, sx->buffer, sizeof(sx->buffer))) <= 0)
2579 {
2580 fd_bits &= ~2;
2581 FD_CLR(proxy_fd, &fds);
2582 shutdown(tls_out.active, SHUT_WR);
2583 }
2584 else
2585 {
2586 for (nbytes = 0; rc - nbytes > 0; nbytes += i)
2587 if ((i = tls_write(FALSE, sx->buffer + nbytes, rc - nbytes)) < 0) return;
2588 }
2589 else if (fd_bits & 2)
2590 FD_SET(proxy_fd, &fds);
2591 }
2592 }
2593 #endif
2594
2595
2596 /*************************************************
2597 * Deliver address list to given host *
2598 *************************************************/
2599
2600 /* If continue_hostname is not null, we get here only when continuing to
2601 deliver down an existing channel. The channel was passed as the standard
2602 input. TLS is never active on a passed channel; the previous process always
2603 closes it down before passing the connection on.
2604
2605 Otherwise, we have to make a connection to the remote host, and do the
2606 initial protocol exchange.
2607
2608 When running as an MUA wrapper, if the sender or any recipient is rejected,
2609 temporarily or permanently, we force failure for all recipients.
2610
2611 Arguments:
2612 addrlist chain of potential addresses to deliver; only those whose
2613 transport_return field is set to PENDING_DEFER are currently
2614 being processed; others should be skipped - they have either
2615 been delivered to an earlier host or IP address, or been
2616 failed by one of them.
2617 host host to deliver to
2618 host_af AF_INET or AF_INET6
2619 port default TCP/IP port to use, in host byte order
2620 interface interface to bind to, or NULL
2621 tblock transport instance block
2622 message_defer set TRUE if yield is OK, but all addresses were deferred
2623 because of a non-recipient, non-host failure, that is, a
2624 4xx response to MAIL FROM, DATA, or ".". This is a defer
2625 that is specific to the message.
2626 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
2627 a second attempt after TLS initialization fails
2628
2629 Returns: OK - the connection was made and the delivery attempted;
2630 the result for each address is in its data block.
2631 DEFER - the connection could not be made, or something failed
2632 while setting up the SMTP session, or there was a
2633 non-message-specific error, such as a timeout.
2634 ERROR - a filter command is specified for this transport,
2635 and there was a problem setting it up; OR helo_data
2636 or add_headers or authenticated_sender is specified
2637 for this transport, and the string failed to expand
2638 */
2639
2640 static int
2641 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
2642 uschar *interface, transport_instance *tblock,
2643 BOOL *message_defer, BOOL suppress_tls)
2644 {
2645 address_item *addr;
2646 int yield = OK;
2647 int save_errno;
2648 int rc;
2649 time_t start_delivery_time = time(NULL);
2650
2651 BOOL pass_message = FALSE;
2652 uschar *message = NULL;
2653 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
2654 uschar *p;
2655
2656 smtp_context sx;
2657
2658 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
2659 *message_defer = FALSE;
2660
2661 sx.addrlist = addrlist;
2662 sx.host = host;
2663 sx.host_af = host_af,
2664 sx.port = port;
2665 sx.interface = interface;
2666 sx.helo_data = NULL;
2667 sx.tblock = tblock;
2668 sx.verify = FALSE;
2669
2670 /* Get the channel set up ready for a message (MAIL FROM being the next
2671 SMTP command to send */
2672
2673 if ((rc = smtp_setup_conn(&sx, suppress_tls)) != OK)
2674 return rc;
2675
2676 /* If there is a filter command specified for this transport, we can now
2677 set it up. This cannot be done until the identify of the host is known. */
2678
2679 if (tblock->filter_command)
2680 {
2681 BOOL rc;
2682 uschar fbuf[64];
2683 sprintf(CS fbuf, "%.50s transport", tblock->name);
2684 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
2685 TRUE, DEFER, addrlist, fbuf, NULL);
2686 transport_filter_timeout = tblock->filter_timeout;
2687
2688 /* On failure, copy the error to all addresses, abandon the SMTP call, and
2689 yield ERROR. */
2690
2691 if (!rc)
2692 {
2693 set_errno_nohost(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
2694 FALSE);
2695 yield = ERROR;
2696 goto SEND_QUIT;
2697 }
2698
2699 if ( transport_filter_argv
2700 && *transport_filter_argv
2701 && **transport_filter_argv
2702 && sx.peer_offered & PEER_OFFERED_CHUNKING
2703 )
2704 {
2705 sx.peer_offered &= ~PEER_OFFERED_CHUNKING;
2706 DEBUG(D_transport) debug_printf("CHUNKING not usable due to transport filter\n");
2707 }
2708 }
2709
2710
2711 /* For messages that have more than the maximum number of envelope recipients,
2712 we want to send several transactions down the same SMTP connection. (See
2713 comments in deliver.c as to how this reconciles, heuristically, with
2714 remote_max_parallel.) This optimization was added to Exim after the following
2715 code was already working. The simplest way to put it in without disturbing the
2716 code was to use a goto to jump back to this point when there is another
2717 transaction to handle. */
2718
2719 SEND_MESSAGE:
2720 sx.from_addr = return_path;
2721 sx.first_addr = sx.sync_addr = addrlist;
2722 sx.ok = FALSE;
2723 sx.send_rset = TRUE;
2724 sx.completed_addr = FALSE;
2725
2726
2727 /* Initiate a message transfer. */
2728
2729 switch(smtp_write_mail_and_rcpt_cmds(&sx, &yield))
2730 {
2731 case 0: break;
2732 case -1: case -2: goto RESPONSE_FAILED;
2733 case -3: goto END_OFF;
2734 case -4: goto SEND_QUIT;
2735 default: goto SEND_FAILED;
2736 }
2737
2738 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
2739 permanently or temporarily. We should have flushed and synced after the last
2740 RCPT. */
2741
2742 if (mua_wrapper)
2743 {
2744 address_item *badaddr;
2745 for (badaddr = sx.first_addr; badaddr; badaddr = badaddr->next)
2746 if (badaddr->transport_return != PENDING_OK)
2747 {
2748 /*XXX could we find a better errno than 0 here? */
2749 set_errno_nohost(addrlist, 0, badaddr->message, FAIL,
2750 testflag(badaddr, af_pass_message));
2751 sx.ok = FALSE;
2752 break;
2753 }
2754 }
2755
2756 /* If ok is TRUE, we know we have got at least one good recipient, and must now
2757 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
2758 have a good recipient buffered up if we are pipelining. We don't want to waste
2759 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
2760 are pipelining. The responses are all handled by sync_responses().
2761 If using CHUNKING, do not send a BDAT until we know how big a chunk we want
2762 to send is. */
2763
2764 if ( !(sx.peer_offered & PEER_OFFERED_CHUNKING)
2765 && (sx.ok || (pipelining_active && !mua_wrapper)))
2766 {
2767 int count = smtp_write_command(&sx.outblock, FALSE, "DATA\r\n");
2768
2769 if (count < 0) goto SEND_FAILED;
2770 switch(sync_responses(&sx, count, sx.ok ? +1 : -1))
2771 {
2772 case 3: sx.ok = TRUE; /* 2xx & 5xx => OK & progress made */
2773 case 2: sx.completed_addr = TRUE; /* 5xx (only) => progress made */
2774 break;
2775
2776 case 1: sx.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2777 if (!sx.lmtp) sx.completed_addr = TRUE; /* can't tell about progress yet */
2778 case 0: break; /* No 2xx or 5xx, but no probs */
2779
2780 case -1: goto END_OFF; /* Timeout on RCPT */
2781 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2782 }
2783 pipelining_active = FALSE;
2784 data_command = string_copy(big_buffer); /* Save for later error message */
2785 }
2786
2787 /* If there were no good recipients (but otherwise there have been no
2788 problems), just set ok TRUE, since we have handled address-specific errors
2789 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
2790 for handling the SMTP dot-handling protocol, flagging to apply to headers as
2791 well as body. Set the appropriate timeout value to be used for each chunk.
2792 (Haven't been able to make it work using select() for writing yet.) */
2793
2794 if (!(sx.peer_offered & PEER_OFFERED_CHUNKING) && !sx.ok)
2795 {
2796 /* Save the first address of the next batch. */
2797 sx.first_addr = sx.next_addr;
2798
2799 sx.ok = TRUE;
2800 }
2801 else
2802 {
2803 transport_ctx tctx = {
2804 tblock,
2805 addrlist,
2806 US".", US"..", /* Escaping strings */
2807 topt_use_crlf | topt_escape_headers
2808 | (tblock->body_only ? topt_no_headers : 0)
2809 | (tblock->headers_only ? topt_no_body : 0)
2810 | (tblock->return_path_add ? topt_add_return_path : 0)
2811 | (tblock->delivery_date_add ? topt_add_delivery_date : 0)
2812 | (tblock->envelope_to_add ? topt_add_envelope_to : 0)
2813 };
2814
2815 /* If using CHUNKING we need a callback from the generic transport
2816 support to us, for the sending of BDAT smtp commands and the reaping
2817 of responses. The callback needs a whole bunch of state so set up
2818 a transport-context structure to be passed around. */
2819
2820 if (sx.peer_offered & PEER_OFFERED_CHUNKING)
2821 {
2822 tctx.check_string = tctx.escape_string = NULL;
2823 tctx.options |= topt_use_bdat;
2824 tctx.chunk_cb = smtp_chunk_cmd_callback;
2825 sx.pending_BDAT = FALSE;
2826 sx.good_RCPT = sx.ok;
2827 sx.cmd_count = 0;
2828 tctx.smtp_context = &sx;
2829 }
2830 else
2831 tctx.options |= topt_end_dot;
2832
2833 /* Save the first address of the next batch. */
2834 sx.first_addr = sx.next_addr;
2835
2836 /* Responses from CHUNKING commands go in buffer. Otherwise,
2837 there has not been a response. */
2838
2839 sx.buffer[0] = 0;
2840
2841 sigalrm_seen = FALSE;
2842 transport_write_timeout = sx.ob->data_timeout;
2843 smtp_command = US"sending data block"; /* For error messages */
2844 DEBUG(D_transport|D_v)
2845 if (sx.peer_offered & PEER_OFFERED_CHUNKING)
2846 debug_printf(" will write message using CHUNKING\n");
2847 else
2848 debug_printf(" SMTP>> writing message and terminating \".\"\n");
2849 transport_count = 0;
2850
2851 #ifndef DISABLE_DKIM
2852 sx.ok = dkim_transport_write_message(sx.inblock.sock, &tctx, &sx.ob->dkim,
2853 CUSS &message);
2854 #else
2855 sx.ok = transport_write_message(sx.inblock.sock, &tctx, 0);
2856 #endif
2857
2858 /* transport_write_message() uses write() because it is called from other
2859 places to write to non-sockets. This means that under some OS (e.g. Solaris)
2860 it can exit with "Broken pipe" as its error. This really means that the
2861 socket got closed at the far end. */
2862
2863 transport_write_timeout = 0; /* for subsequent transports */
2864
2865 /* Failure can either be some kind of I/O disaster (including timeout),
2866 or the failure of a transport filter or the expansion of added headers.
2867 Or, when CHUNKING, it can be a protocol-detected failure. */
2868
2869 if (!sx.ok)
2870 if (message) goto SEND_FAILED;
2871 else goto RESPONSE_FAILED;
2872
2873 /* We used to send the terminating "." explicitly here, but because of
2874 buffering effects at both ends of TCP/IP connections, you don't gain
2875 anything by keeping it separate, so it might as well go in the final
2876 data buffer for efficiency. This is now done by setting the topt_end_dot
2877 flag above. */
2878
2879 smtp_command = US"end of data";
2880
2881 if (sx.peer_offered & PEER_OFFERED_CHUNKING && sx.cmd_count > 1)
2882 {
2883 /* Reap any outstanding MAIL & RCPT commands, but not a DATA-go-ahead */
2884 switch(sync_responses(&sx, sx.cmd_count-1, 0))
2885 {
2886 case 3: sx.ok = TRUE; /* 2xx & 5xx => OK & progress made */
2887 case 2: sx.completed_addr = TRUE; /* 5xx (only) => progress made */
2888 break;
2889
2890 case 1: sx.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2891 if (!sx.lmtp) sx.completed_addr = TRUE; /* can't tell about progress yet */
2892 case 0: break; /* No 2xx or 5xx, but no probs */
2893
2894 case -1: goto END_OFF; /* Timeout on RCPT */
2895 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2896 }
2897 }
2898
2899 #ifndef DISABLE_PRDR
2900 /* For PRDR we optionally get a partial-responses warning
2901 * followed by the individual responses, before going on with
2902 * the overall response. If we don't get the warning then deal
2903 * with per non-PRDR. */
2904 if(sx.prdr_active)
2905 {
2906 sx.ok = smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer), '3',
2907 sx.ob->final_timeout);
2908 if (!sx.ok && errno == 0) switch(sx.buffer[0])
2909 {
2910 case '2': sx.prdr_active = FALSE;
2911 sx.ok = TRUE;
2912 break;
2913 case '4': errno = ERRNO_DATA4XX;
2914 addrlist->more_errno |=
2915 ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
2916 break;
2917 }
2918 }
2919 else
2920 #endif
2921
2922 /* For non-PRDR SMTP, we now read a single response that applies to the
2923 whole message. If it is OK, then all the addresses have been delivered. */
2924
2925 if (!sx.lmtp)
2926 {
2927 sx.ok = smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer), '2',
2928 sx.ob->final_timeout);
2929 if (!sx.ok && errno == 0 && sx.buffer[0] == '4')
2930 {
2931 errno = ERRNO_DATA4XX;
2932 addrlist->more_errno |= ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
2933 }
2934 }
2935
2936 /* For LMTP, we get back a response for every RCPT command that we sent;
2937 some may be accepted and some rejected. For those that get a response, their
2938 status is fixed; any that are accepted have been handed over, even if later
2939 responses crash - at least, that's how I read RFC 2033.
2940
2941 If all went well, mark the recipient addresses as completed, record which
2942 host/IPaddress they were delivered to, and cut out RSET when sending another
2943 message down the same channel. Write the completed addresses to the journal
2944 now so that they are recorded in case there is a crash of hardware or
2945 software before the spool gets updated. Also record the final SMTP
2946 confirmation if needed (for SMTP only). */
2947
2948 if (sx.ok)
2949 {
2950 int flag = '=';
2951 int delivery_time = (int)(time(NULL) - start_delivery_time);
2952 int len;
2953 uschar *conf = NULL;
2954
2955 sx.send_rset = FALSE;
2956 pipelining_active = FALSE;
2957
2958 /* Set up confirmation if needed - applies only to SMTP */
2959
2960 if (
2961 #ifdef DISABLE_EVENT
2962 LOGGING(smtp_confirmation) &&
2963 #endif
2964 !sx.lmtp
2965 )
2966 {
2967 const uschar *s = string_printing(sx.buffer);
2968 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
2969 conf = (s == sx.buffer)? (uschar *)string_copy(s) : US s;
2970 }
2971
2972 /* Process all transported addresses - for LMTP or PRDR, read a status for
2973 each one. */
2974
2975 for (addr = addrlist; addr != sx.first_addr; addr = addr->next)
2976 {
2977 if (addr->transport_return != PENDING_OK) continue;
2978
2979 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
2980 remaining addresses. Otherwise, it's a return code for just the one
2981 address. For temporary errors, add a retry item for the address so that
2982 it doesn't get tried again too soon. */
2983
2984 #ifndef DISABLE_PRDR
2985 if (sx.lmtp || sx.prdr_active)
2986 #else
2987 if (sx.lmtp)
2988 #endif
2989 {
2990 if (!smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer), '2',
2991 sx.ob->final_timeout))
2992 {
2993 if (errno != 0 || sx.buffer[0] == 0) goto RESPONSE_FAILED;
2994 addr->message = string_sprintf(
2995 #ifndef DISABLE_PRDR
2996 "%s error after %s: %s", sx.prdr_active ? "PRDR":"LMTP",
2997 #else
2998 "LMTP error after %s: %s",
2999 #endif
3000 data_command, string_printing(sx.buffer));
3001 setflag(addr, af_pass_message); /* Allow message to go to user */
3002 if (sx.buffer[0] == '5')
3003 addr->transport_return = FAIL;
3004 else
3005 {
3006 errno = ERRNO_DATA4XX;
3007 addr->more_errno |= ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
3008 addr->transport_return = DEFER;
3009 #ifndef DISABLE_PRDR
3010 if (!sx.prdr_active)
3011 #endif
3012 retry_add_item(addr, addr->address_retry_key, 0);
3013 }
3014 continue;
3015 }
3016 sx.completed_addr = TRUE; /* NOW we can set this flag */
3017 if (LOGGING(smtp_confirmation))
3018 {
3019 const uschar *s = string_printing(sx.buffer);
3020 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
3021 conf = (s == sx.buffer) ? US string_copy(s) : US s;
3022 }
3023 }
3024
3025 /* SMTP, or success return from LMTP for this address. Pass back the
3026 actual host that was used. */
3027
3028 addr->transport_return = OK;
3029 addr->more_errno = delivery_time;
3030 addr->host_used = host;
3031 addr->special_action = flag;
3032 addr->message = conf;
3033 #ifndef DISABLE_PRDR
3034 if (sx.prdr_active) addr->flags |= af_prdr_used;
3035 #endif
3036 if (sx.peer_offered & PEER_OFFERED_CHUNKING) addr->flags |= af_chunking_used;
3037 flag = '-';
3038
3039 #ifndef DISABLE_PRDR
3040 if (!sx.prdr_active)
3041 #endif
3042 {
3043 /* Update the journal. For homonymic addresses, use the base address plus
3044 the transport name. See lots of comments in deliver.c about the reasons
3045 for the complications when homonyms are involved. Just carry on after
3046 write error, as it may prove possible to update the spool file later. */
3047
3048 if (testflag(addr, af_homonym))
3049 sprintf(CS sx.buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
3050 else
3051 sprintf(CS sx.buffer, "%.500s\n", addr->unique);
3052
3053 DEBUG(D_deliver) debug_printf("journalling %s\n", sx.buffer);
3054 len = Ustrlen(CS sx.buffer);
3055 if (write(journal_fd, sx.buffer, len) != len)
3056 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
3057 "%s: %s", sx.buffer, strerror(errno));
3058 }
3059 }
3060
3061 #ifndef DISABLE_PRDR
3062 if (sx.prdr_active)
3063 {
3064 /* PRDR - get the final, overall response. For any non-success
3065 upgrade all the address statuses. */
3066 sx.ok = smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer), '2',
3067 sx.ob->final_timeout);
3068 if (!sx.ok)
3069 {
3070 if(errno == 0 && sx.buffer[0] == '4')
3071 {
3072 errno = ERRNO_DATA4XX;
3073 addrlist->more_errno |= ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
3074 }
3075 for (addr = addrlist; addr != sx.first_addr; addr = addr->next)
3076 if (sx.buffer[0] == '5' || addr->transport_return == OK)
3077 addr->transport_return = PENDING_OK; /* allow set_errno action */
3078 goto RESPONSE_FAILED;
3079 }
3080
3081 /* Update the journal, or setup retry. */
3082 for (addr = addrlist; addr != sx.first_addr; addr = addr->next)
3083 if (addr->transport_return == OK)
3084 {
3085 if (testflag(addr, af_homonym))
3086 sprintf(CS sx.buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
3087 else
3088 sprintf(CS sx.buffer, "%.500s\n", addr->unique);
3089
3090 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s\n", sx.buffer);
3091 len = Ustrlen(CS sx.buffer);
3092 if (write(journal_fd, sx.buffer, len) != len)
3093 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
3094 "%s: %s", sx.buffer, strerror(errno));
3095 }
3096 else if (addr->transport_return == DEFER)
3097 retry_add_item(addr, addr->address_retry_key, -2);
3098 }
3099 #endif
3100
3101 /* Ensure the journal file is pushed out to disk. */
3102
3103 if (EXIMfsync(journal_fd) < 0)
3104 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
3105 strerror(errno));
3106 }
3107 }
3108
3109
3110 /* Handle general (not specific to one address) failures here. The value of ok
3111 is used to skip over this code on the falling through case. A timeout causes a
3112 deferral. Other errors may defer or fail according to the response code, and
3113 may set up a special errno value, e.g. after connection chopped, which is
3114 assumed if errno == 0 and there is no text in the buffer. If control reaches
3115 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
3116 the problem is not related to this specific message. */
3117
3118 if (!sx.ok)
3119 {
3120 int code, set_rc;
3121 uschar * set_message;
3122
3123 RESPONSE_FAILED:
3124 {
3125 save_errno = errno;
3126 message = NULL;
3127 sx.send_quit = check_response(host, &save_errno, addrlist->more_errno,
3128 sx.buffer, &code, &message, &pass_message);
3129 goto FAILED;
3130 }
3131
3132 SEND_FAILED:
3133 {
3134 save_errno = errno;
3135 code = '4';
3136 message = string_sprintf("send() to %s [%s] failed: %s",
3137 host->name, host->address, message ? message : US strerror(save_errno));
3138 sx.send_quit = FALSE;
3139 goto FAILED;
3140 }
3141
3142 FAILED:
3143 {
3144 BOOL message_error;
3145
3146 sx.ok = FALSE; /* For when reached by GOTO */
3147 set_message = message;
3148
3149 /* We want to handle timeouts after MAIL or "." and loss of connection after
3150 "." specially. They can indicate a problem with the sender address or with
3151 the contents of the message rather than a real error on the connection. These
3152 cases are treated in the same way as a 4xx response. This next bit of code
3153 does the classification. */
3154
3155 switch(save_errno)
3156 {
3157 case 0:
3158 case ERRNO_MAIL4XX:
3159 case ERRNO_DATA4XX:
3160 message_error = TRUE;
3161 break;
3162
3163 case ETIMEDOUT:
3164 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
3165 Ustrncmp(smtp_command,"end ",4) == 0;
3166 break;
3167
3168 case ERRNO_SMTPCLOSED:
3169 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
3170 break;
3171
3172 default:
3173 message_error = FALSE;
3174 break;
3175 }
3176
3177 /* Handle the cases that are treated as message errors. These are:
3178
3179 (a) negative response or timeout after MAIL
3180 (b) negative response after DATA
3181 (c) negative response or timeout or dropped connection after "."
3182 (d) utf8 support required and not offered
3183
3184 It won't be a negative response or timeout after RCPT, as that is dealt
3185 with separately above. The action in all cases is to set an appropriate
3186 error code for all the addresses, but to leave yield set to OK because the
3187 host itself has not failed. Of course, it might in practice have failed
3188 when we've had a timeout, but if so, we'll discover that at the next
3189 delivery attempt. For a temporary error, set the message_defer flag, and
3190 write to the logs for information if this is not the last host. The error
3191 for the last host will be logged as part of the address's log line. */
3192
3193 if (message_error)
3194 {
3195 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
3196
3197 /* If there's an errno, the message contains just the identity of
3198 the host. */
3199
3200 if (code == '5')
3201 set_rc = FAIL;
3202 else /* Anything other than 5 is treated as temporary */
3203 {
3204 set_rc = DEFER;
3205 if (save_errno > 0)
3206 message = US string_sprintf("%s: %s", message, strerror(save_errno));
3207 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
3208 msglog_line(host, message);
3209 *message_defer = TRUE;
3210 }
3211 }
3212
3213 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
3214 ".", or some other transportation error. We defer all addresses and yield
3215 DEFER, except for the case of failed add_headers expansion, or a transport
3216 filter failure, when the yield should be ERROR, to stop it trying other
3217 hosts. */
3218
3219 else
3220 {
3221 set_rc = DEFER;
3222 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
3223 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
3224 }
3225 }
3226
3227 set_errno(addrlist, save_errno, set_message, set_rc, pass_message, host
3228 #ifdef EXPERIMENTAL_DSN_INFO
3229 , sx.smtp_greeting, sx.helo_response
3230 #endif
3231 );
3232 }
3233
3234
3235 /* If all has gone well, send_quit will be set TRUE, implying we can end the
3236 SMTP session tidily. However, if there were too many addresses to send in one
3237 message (indicated by first_addr being non-NULL) we want to carry on with the
3238 rest of them. Also, it is desirable to send more than one message down the SMTP
3239 connection if there are several waiting, provided we haven't already sent so
3240 many as to hit the configured limit. The function transport_check_waiting looks
3241 for a waiting message and returns its id. Then transport_pass_socket tries to
3242 set up a continued delivery by passing the socket on to another process. The
3243 variable send_rset is FALSE if a message has just been successfully transfered.
3244
3245 If we are already sending down a continued channel, there may be further
3246 addresses not yet delivered that are aimed at the same host, but which have not
3247 been passed in this run of the transport. In this case, continue_more will be
3248 true, and all we should do is send RSET if necessary, and return, leaving the
3249 channel open.
3250
3251 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
3252 do not want to continue with other messages down the same channel, because that
3253 can lead to looping between two or more messages, all with the same,
3254 temporarily failing address(es). [The retry information isn't updated yet, so
3255 new processes keep on trying.] We probably also don't want to try more of this
3256 message's addresses either.
3257
3258 If we have started a TLS session, we have to end it before passing the
3259 connection to a new process. However, not all servers can handle this (Exim
3260 can), so we do not pass such a connection on if the host matches
3261 hosts_nopass_tls. */
3262
3263 DEBUG(D_transport)
3264 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
3265 "yield=%d first_address is %sNULL\n", sx.ok, sx.send_quit,
3266 sx.send_rset, continue_more, yield, sx.first_addr ? "not " : "");
3267
3268 if (sx.completed_addr && sx.ok && sx.send_quit)
3269 {
3270 BOOL more;
3271 smtp_compare_t t_compare;
3272
3273 t_compare.tblock = tblock;
3274 t_compare.current_sender_address = sender_address;
3275
3276 if ( sx.first_addr != NULL
3277 || continue_more
3278 || (
3279 #ifdef SUPPORT_TLS
3280 ( tls_out.active < 0 && !continue_proxy
3281 || verify_check_given_host(&sx.ob->hosts_nopass_tls, host) != OK
3282 )
3283 &&
3284 #endif
3285 transport_check_waiting(tblock->name, host->name,
3286 tblock->connection_max_messages, new_message_id, &more,
3287 (oicf)smtp_are_same_identities, (void*)&t_compare)
3288 ) )
3289 {
3290 uschar *msg;
3291 BOOL pass_message;
3292
3293 if (sx.send_rset)
3294 if (! (sx.ok = smtp_write_command(&sx.outblock, FALSE, "RSET\r\n") >= 0))
3295 {
3296 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
3297 host->address, strerror(errno));
3298 sx.send_quit = FALSE;
3299 }
3300 else if (! (sx.ok = smtp_read_response(&sx.inblock, sx.buffer,
3301 sizeof(sx.buffer), '2', sx.ob->command_timeout)))
3302 {
3303 int code;
3304 sx.send_quit = check_response(host, &errno, 0, sx.buffer, &code, &msg,
3305 &pass_message);
3306 if (!sx.send_quit)
3307 {
3308 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
3309 host->name, host->address, msg);
3310 }
3311 }
3312
3313 /* Either RSET was not needed, or it succeeded */
3314
3315 if (sx.ok)
3316 {
3317 int pfd[2];
3318 int socket_fd = sx.inblock.sock;
3319
3320
3321 if (sx.first_addr != NULL) /* More addresses still to be sent */
3322 { /* in this run of the transport */
3323 continue_sequence++; /* Causes * in logging */
3324 goto SEND_MESSAGE;
3325 }
3326 if (continue_more) return yield; /* More addresses for another run */
3327
3328 /* Pass the connection on to a new Exim process. */
3329 #ifdef SUPPORT_TLS
3330 if (tls_out.active >= 0)
3331 if (verify_check_given_host(&sx.ob->hosts_noproxy_tls, host) == OK)
3332 {
3333 /* Pass the socket, for direct use, to a new Exim process. Before
3334 doing so, we must shut down TLS. Not all MTAs allow for the
3335 continuation of the SMTP session when TLS is shut down. We test for
3336 this by sending a new EHLO. If we don't get a good response, we don't
3337 attempt to pass the socket on. */
3338
3339 tls_close(FALSE, TRUE);
3340 smtp_peer_options = smtp_peer_options_wrap;
3341 sx.ok = !sx.smtps
3342 && smtp_write_command(&sx.outblock, FALSE,
3343 "EHLO %s\r\n", sx.helo_data) >= 0
3344 && smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer),
3345 '2', sx.ob->command_timeout);
3346 }
3347 else
3348 {
3349 /* Set up a pipe for proxying TLS for the new transport process */
3350
3351 smtp_peer_options |= PEER_OFFERED_TLS;
3352 if (sx.ok = (socketpair(AF_LOCAL, SOCK_STREAM, 0, pfd) == 0))
3353 socket_fd = pfd[1];
3354 else
3355 set_errno(sx.first_addr, errno, US"internal allocation problem",
3356 DEFER, FALSE, host
3357 # ifdef EXPERIMENTAL_DSN_INFO
3358 , sx.smtp_greeting, sx.helo_response
3359 # endif
3360 );
3361 }
3362 #endif
3363
3364 /* If the socket is successfully passed, we mustn't send QUIT (or
3365 indeed anything!) from here. */
3366
3367 /*XXX DSN_INFO: assume likely to do new HELO; but for greet we'll want to
3368 propagate it from the initial
3369 */
3370 if (sx.ok && transport_pass_socket(tblock->name, host->name,
3371 host->address, new_message_id, socket_fd))
3372 {
3373 sx.send_quit = FALSE;
3374
3375 /* If TLS is still active, we need to proxy it for the transport we
3376 just passed the baton to. Fork a child to to do it, and return to
3377 get logging done asap. Which way to place the work makes assumptions
3378 about post-fork prioritisation which may not hold on all platforms. */
3379
3380 if (tls_out.active >= 0)
3381 {
3382 int pid = fork();
3383 if (pid > 0) /* parent */
3384 {
3385 tls_close(FALSE, FALSE);
3386 (void)close(sx.inblock.sock);
3387 continue_transport = NULL;
3388 continue_hostname = NULL;
3389 return yield;
3390 }
3391 else if (pid == 0) /* child */
3392 {
3393 smtp_proxy_tls(&sx, pfd[0], sx.ob->command_timeout);
3394 exim_exit(0);
3395 }
3396 }
3397 }
3398 }
3399
3400 /* If RSET failed and there are addresses left, they get deferred. */
3401 else
3402 set_errno(sx.first_addr, errno, msg, DEFER, FALSE, host
3403 #ifdef EXPERIMENTAL_DSN_INFO
3404 , sx.smtp_greeting, sx.helo_response
3405 #endif
3406 );
3407 }
3408 }
3409
3410 /* End off tidily with QUIT unless the connection has died or the socket has
3411 been passed to another process. There has been discussion on the net about what
3412 to do after sending QUIT. The wording of the RFC suggests that it is necessary
3413 to wait for a response, but on the other hand, there isn't anything one can do
3414 with an error response, other than log it. Exim used to do that. However,
3415 further discussion suggested that it is positively advantageous not to wait for
3416 the response, but to close the session immediately. This is supposed to move
3417 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
3418 load from the server. (Hosts that are both servers and clients may not see much
3419 difference, of course.) Further discussion indicated that this was safe to do
3420 on Unix systems which have decent implementations of TCP/IP that leave the
3421 connection around for a while (TIME_WAIT) after the application has gone away.
3422 This enables the response sent by the server to be properly ACKed rather than
3423 timed out, as can happen on broken TCP/IP implementations on other OS.
3424
3425 This change is being made on 31-Jul-98. After over a year of trouble-free
3426 operation, the old commented-out code was removed on 17-Sep-99. */
3427
3428 SEND_QUIT:
3429 if (sx.send_quit) (void)smtp_write_command(&sx.outblock, FALSE, "QUIT\r\n");
3430
3431 END_OFF:
3432
3433 #ifdef SUPPORT_TLS
3434 tls_close(FALSE, TRUE);
3435 #endif
3436
3437 /* Close the socket, and return the appropriate value, first setting
3438 works because the NULL setting is passed back to the calling process, and
3439 remote_max_parallel is forced to 1 when delivering over an existing connection,
3440
3441 If all went well and continue_more is set, we shouldn't actually get here if
3442 there are further addresses, as the return above will be taken. However,
3443 writing RSET might have failed, or there may be other addresses whose hosts are
3444 specified in the transports, and therefore not visible at top level, in which
3445 case continue_more won't get set. */
3446
3447 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
3448 if (sx.send_quit)
3449 {
3450 shutdown(sx.outblock.sock, SHUT_WR);
3451 if (fcntl(sx.inblock.sock, F_SETFL, O_NONBLOCK) == 0)
3452 for (rc = 16; read(sx.inblock.sock, sx.inbuffer, sizeof(sx.inbuffer)) > 0 && rc > 0;)
3453 rc--; /* drain socket */
3454 }
3455 (void)close(sx.inblock.sock);
3456
3457 #ifndef DISABLE_EVENT
3458 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
3459 #endif
3460
3461 continue_transport = NULL;
3462 continue_hostname = NULL;
3463 return yield;
3464 }
3465
3466
3467
3468
3469 /*************************************************
3470 * Closedown entry point *
3471 *************************************************/
3472
3473 /* This function is called when exim is passed an open smtp channel
3474 from another incarnation, but the message which it has been asked
3475 to deliver no longer exists. The channel is on stdin.
3476
3477 We might do fancy things like looking for another message to send down
3478 the channel, but if the one we sought has gone, it has probably been
3479 delivered by some other process that itself will seek further messages,
3480 so just close down our connection.
3481
3482 Argument: pointer to the transport instance block
3483 Returns: nothing
3484 */
3485
3486 void
3487 smtp_transport_closedown(transport_instance *tblock)
3488 {
3489 smtp_transport_options_block *ob =
3490 (smtp_transport_options_block *)tblock->options_block;
3491 smtp_inblock inblock;
3492 smtp_outblock outblock;
3493 uschar buffer[256];
3494 uschar inbuffer[4096];
3495 uschar outbuffer[16];
3496
3497 inblock.sock = fileno(stdin);
3498 inblock.buffer = inbuffer;
3499 inblock.buffersize = sizeof(inbuffer);
3500 inblock.ptr = inbuffer;
3501 inblock.ptrend = inbuffer;
3502
3503 outblock.sock = inblock.sock;
3504 outblock.buffersize = sizeof(outbuffer);
3505 outblock.buffer = outbuffer;
3506 outblock.ptr = outbuffer;
3507 outblock.cmd_count = 0;
3508 outblock.authenticating = FALSE;
3509
3510 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
3511 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
3512 ob->command_timeout);
3513 (void)close(inblock.sock);
3514 }
3515
3516
3517
3518 /*************************************************
3519 * Prepare addresses for delivery *
3520 *************************************************/
3521
3522 /* This function is called to flush out error settings from previous delivery
3523 attempts to other hosts. It also records whether we got here via an MX record
3524 or not in the more_errno field of the address. We are interested only in
3525 addresses that are still marked DEFER - others may have got delivered to a
3526 previously considered IP address. Set their status to PENDING_DEFER to indicate
3527 which ones are relevant this time.
3528
3529 Arguments:
3530 addrlist the list of addresses
3531 host the host we are delivering to
3532
3533 Returns: the first address for this delivery
3534 */
3535
3536 static address_item *
3537 prepare_addresses(address_item *addrlist, host_item *host)
3538 {
3539 address_item *first_addr = NULL;
3540 address_item *addr;
3541 for (addr = addrlist; addr; addr = addr->next)
3542 if (addr->transport_return == DEFER)
3543 {
3544 if (!first_addr) first_addr = addr;
3545 addr->transport_return = PENDING_DEFER;
3546 addr->basic_errno = 0;
3547 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
3548 addr->message = NULL;
3549 #ifdef SUPPORT_TLS
3550 addr->cipher = NULL;
3551 addr->ourcert = NULL;
3552 addr->peercert = NULL;
3553 addr->peerdn = NULL;
3554 addr->ocsp = OCSP_NOT_REQ;
3555 #endif
3556 #ifdef EXPERIMENTAL_DSN_INFO
3557 addr->smtp_greeting = NULL;
3558 addr->helo_response = NULL;
3559 #endif
3560 }
3561 return first_addr;
3562 }
3563
3564
3565
3566 /*************************************************
3567 * Main entry point *
3568 *************************************************/
3569
3570 /* See local README for interface details. As this is a remote transport, it is
3571 given a chain of addresses to be delivered in one connection, if possible. It
3572 always returns TRUE, indicating that each address has its own independent
3573 status set, except if there is a setting up problem, in which case it returns
3574 FALSE. */
3575
3576 BOOL
3577 smtp_transport_entry(
3578 transport_instance *tblock, /* data for this instantiation */
3579 address_item *addrlist) /* addresses we are working on */
3580 {
3581 int cutoff_retry;
3582 int port;
3583 int hosts_defer = 0;
3584 int hosts_fail = 0;
3585 int hosts_looked_up = 0;
3586 int hosts_retry = 0;
3587 int hosts_serial = 0;
3588 int hosts_total = 0;
3589 int total_hosts_tried = 0;
3590 address_item *addr;
3591 BOOL expired = TRUE;
3592 uschar *expanded_hosts = NULL;
3593 uschar *pistring;
3594 uschar *tid = string_sprintf("%s transport", tblock->name);
3595 smtp_transport_options_block *ob =
3596 (smtp_transport_options_block *)(tblock->options_block);
3597 host_item *hostlist = addrlist->host_list;
3598 host_item *host = NULL;
3599
3600 DEBUG(D_transport)
3601 {
3602 debug_printf("%s transport entered\n", tblock->name);
3603 for (addr = addrlist; addr; addr = addr->next)
3604 debug_printf(" %s\n", addr->address);
3605 if (hostlist)
3606 {
3607 debug_printf("hostlist:\n");
3608 for (host = hostlist; host; host = host->next)
3609 debug_printf(" %s:%d\n", host->name, host->port);
3610 }
3611 if (continue_hostname) debug_printf("already connected to %s [%s]\n",
3612 continue_hostname, continue_host_address);
3613 }
3614
3615 /* Set the flag requesting that these hosts be added to the waiting
3616 database if the delivery fails temporarily or if we are running with
3617 queue_smtp or a 2-stage queue run. This gets unset for certain
3618 kinds of error, typically those that are specific to the message. */
3619
3620 update_waiting = TRUE;
3621
3622 /* If a host list is not defined for the addresses - they must all have the
3623 same one in order to be passed to a single transport - or if the transport has
3624 a host list with hosts_override set, use the host list supplied with the
3625 transport. It is an error for this not to exist. */
3626
3627 if (!hostlist || (ob->hosts_override && ob->hosts))
3628 {
3629 if (!ob->hosts)
3630 {
3631 addrlist->message = string_sprintf("%s transport called with no hosts set",
3632 tblock->name);
3633 addrlist->transport_return = PANIC;
3634 return FALSE; /* Only top address has status */
3635 }
3636
3637 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
3638 ob->hosts);
3639
3640 /* If the transport's host list contains no '$' characters, and we are not
3641 randomizing, it is fixed and therefore a chain of hosts can be built once
3642 and for all, and remembered for subsequent use by other calls to this
3643 transport. If, on the other hand, the host list does contain '$', or we are
3644 randomizing its order, we have to rebuild it each time. In the fixed case,
3645 as the hosts string will never be used again, it doesn't matter that we
3646 replace all the : characters with zeros. */
3647
3648 if (!ob->hostlist)
3649 {
3650 uschar *s = ob->hosts;
3651
3652 if (Ustrchr(s, '$') != NULL)
3653 {
3654 if (!(expanded_hosts = expand_string(s)))
3655 {
3656 addrlist->message = string_sprintf("failed to expand list of hosts "
3657 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
3658 addrlist->transport_return = search_find_defer ? DEFER : PANIC;
3659 return FALSE; /* Only top address has status */
3660 }
3661 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
3662 "\"%s\"\n", s, expanded_hosts);
3663 s = expanded_hosts;
3664 }
3665 else
3666 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
3667
3668 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
3669
3670 /* Check that the expansion yielded something useful. */
3671 if (!hostlist)
3672 {
3673 addrlist->message =
3674 string_sprintf("%s transport has empty hosts setting", tblock->name);
3675 addrlist->transport_return = PANIC;
3676 return FALSE; /* Only top address has status */
3677 }
3678
3679 /* If there was no expansion of hosts, save the host list for
3680 next time. */
3681
3682 if (!expanded_hosts) ob->hostlist = hostlist;
3683 }
3684
3685 /* This is not the first time this transport has been run in this delivery;
3686 the host list was built previously. */
3687
3688 else
3689 hostlist = ob->hostlist;
3690 }
3691
3692 /* The host list was supplied with the address. If hosts_randomize is set, we
3693 must sort it into a random order if it did not come from MX records and has not
3694 already been randomized (but don't bother if continuing down an existing
3695 connection). */
3696
3697 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continue_hostname)
3698 {
3699 host_item *newlist = NULL;
3700 while (hostlist)
3701 {
3702 host_item *h = hostlist;
3703 hostlist = hostlist->next;
3704
3705 h->sort_key = random_number(100);
3706
3707 if (!newlist)
3708 {
3709 h->next = NULL;
3710 newlist = h;
3711 }
3712 else if (h->sort_key < newlist->sort_key)
3713 {
3714 h->next = newlist;
3715 newlist = h;
3716 }
3717 else
3718 {
3719 host_item *hh = newlist;
3720 while (hh->next)
3721 {
3722 if (h->sort_key < hh->next->sort_key) break;
3723 hh = hh->next;
3724 }
3725 h->next = hh->next;
3726 hh->next = h;
3727 }
3728 }
3729
3730 hostlist = addrlist->host_list = newlist;
3731 }
3732
3733 /* Sort out the default port. */
3734
3735 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
3736
3737 /* For each host-plus-IP-address on the list:
3738
3739 . If this is a continued delivery and the host isn't the one with the
3740 current connection, skip.
3741
3742 . If the status is unusable (i.e. previously failed or retry checked), skip.
3743
3744 . If no IP address set, get the address, either by turning the name into
3745 an address, calling gethostbyname if gethostbyname is on, or by calling
3746 the DNS. The DNS may yield multiple addresses, in which case insert the
3747 extra ones into the list.
3748
3749 . Get the retry data if not previously obtained for this address and set the
3750 field which remembers the state of this address. Skip if the retry time is
3751 not reached. If not, remember whether retry data was found. The retry string
3752 contains both the name and the IP address.
3753
3754 . Scan the list of addresses and mark those whose status is DEFER as
3755 PENDING_DEFER. These are the only ones that will be processed in this cycle
3756 of the hosts loop.
3757
3758 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
3759 Some addresses may be successfully delivered, others may fail, and yet
3760 others may get temporary errors and so get marked DEFER.
3761
3762 . The return from the delivery attempt is OK if a connection was made and a
3763 valid SMTP dialogue was completed. Otherwise it is DEFER.
3764
3765 . If OK, add a "remove" retry item for this host/IPaddress, if any.
3766
3767 . If fail to connect, or other defer state, add a retry item.
3768
3769 . If there are any addresses whose status is still DEFER, carry on to the
3770 next host/IPaddress, unless we have tried the number of hosts given
3771 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
3772 there is some fancy logic for hosts_max_try that means its limit can be
3773 overstepped in some circumstances.
3774
3775 If we get to the end of the list, all hosts have deferred at least one address,
3776 or not reached their retry times. If delay_after_cutoff is unset, it requests a
3777 delivery attempt to those hosts whose last try was before the arrival time of
3778 the current message. To cope with this, we have to go round the loop a second
3779 time. After that, set the status and error data for any addresses that haven't
3780 had it set already. */
3781
3782 for (cutoff_retry = 0;
3783 expired && cutoff_retry < (ob->delay_after_cutoff ? 1 : 2);
3784 cutoff_retry++)
3785 {
3786 host_item *nexthost = NULL;
3787 int unexpired_hosts_tried = 0;
3788
3789 for (host = hostlist;
3790 host
3791 && unexpired_hosts_tried < ob->hosts_max_try
3792 && total_hosts_tried < ob->hosts_max_try_hardlimit;
3793 host = nexthost)
3794 {
3795 int rc;
3796 int host_af;
3797 uschar *rs;
3798 BOOL host_is_expired = FALSE;
3799 BOOL message_defer = FALSE;
3800 BOOL some_deferred = FALSE;
3801 address_item *first_addr = NULL;
3802 uschar *interface = NULL;
3803 uschar *retry_host_key = NULL;
3804 uschar *retry_message_key = NULL;
3805 uschar *serialize_key = NULL;
3806
3807 /* Default next host is next host. :-) But this can vary if the
3808 hosts_max_try limit is hit (see below). It may also be reset if a host
3809 address is looked up here (in case the host was multihomed). */
3810
3811 nexthost = host->next;
3812
3813 /* If the address hasn't yet been obtained from the host name, look it up
3814 now, unless the host is already marked as unusable. If it is marked as
3815 unusable, it means that the router was unable to find its IP address (in
3816 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
3817 the lookup failed last time. We don't get this far if *all* MX records
3818 point to non-existent hosts; that is treated as a hard error.
3819
3820 We can just skip this host entirely. When the hosts came from the router,
3821 the address will timeout based on the other host(s); when the address is
3822 looked up below, there is an explicit retry record added.
3823
3824 Note that we mustn't skip unusable hosts if the address is not unset; they
3825 may be needed as expired hosts on the 2nd time round the cutoff loop. */
3826
3827 if (!host->address)
3828 {
3829 int new_port, flags;
3830 host_item *hh;
3831
3832 if (host->status >= hstatus_unusable)
3833 {
3834 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
3835 host->name);
3836 continue;
3837 }
3838
3839 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
3840
3841 /* The host name is permitted to have an attached port. Find it, and
3842 strip it from the name. Just remember it for now. */
3843
3844 new_port = host_item_get_port(host);
3845
3846 /* Count hosts looked up */
3847
3848 hosts_looked_up++;
3849
3850 /* Find by name if so configured, or if it's an IP address. We don't
3851 just copy the IP address, because we need the test-for-local to happen. */
3852
3853 flags = HOST_FIND_BY_A;
3854 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
3855 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
3856
3857 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
3858 rc = host_find_byname(host, NULL, flags, NULL, TRUE);
3859 else
3860 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
3861 &ob->dnssec, /* domains for request/require */
3862 NULL, NULL);
3863
3864 /* Update the host (and any additional blocks, resulting from
3865 multihoming) with a host-specific port, if any. */
3866
3867 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
3868
3869 /* Failure to find the host at this time (usually DNS temporary failure)
3870 is really a kind of routing failure rather than a transport failure.
3871 Therefore we add a retry item of the routing kind, not to stop us trying
3872 to look this name up here again, but to ensure the address gets timed
3873 out if the failures go on long enough. A complete failure at this point
3874 commonly points to a configuration error, but the best action is still
3875 to carry on for the next host. */
3876
3877 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_SECURITY || rc == HOST_FIND_FAILED)
3878 {
3879 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
3880 expired = FALSE;
3881 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
3882 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
3883 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
3884 host->status = hstatus_unusable;
3885
3886 for (addr = addrlist; addr; addr = addr->next)
3887 {
3888 if (addr->transport_return != DEFER) continue;
3889 addr->basic_errno = ERRNO_UNKNOWNHOST;
3890 addr->message = string_sprintf(
3891 rc == HOST_FIND_SECURITY
3892 ? "lookup of IP address for %s was insecure"
3893 : "failed to lookup IP address for %s",
3894 host->name);
3895 }
3896 continue;
3897 }
3898
3899 /* If the host is actually the local host, we may have a problem, or
3900 there may be some cunning configuration going on. In the problem case,
3901 log things and give up. The default transport status is already DEFER. */
3902
3903 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
3904 {
3905 for (addr = addrlist; addr; addr = addr->next)
3906 {
3907 addr->basic_errno = 0;
3908 addr->message = string_sprintf("%s transport found host %s to be "
3909 "local", tblock->name, host->name);
3910 }
3911 goto END_TRANSPORT;
3912 }
3913 } /* End of block for IP address lookup */
3914
3915 /* If this is a continued delivery, we are interested only in the host
3916 which matches the name of the existing open channel. The check is put
3917 here after the local host lookup, in case the name gets expanded as a
3918 result of the lookup. Set expired FALSE, to save the outer loop executing
3919 twice. */
3920
3921 if ( continue_hostname
3922 && ( Ustrcmp(continue_hostname, host->name) != 0
3923 || Ustrcmp(continue_host_address, host->address) != 0
3924 ) )
3925 {
3926 expired = FALSE;
3927 continue; /* With next host */
3928 }
3929
3930 /* Reset the default next host in case a multihomed host whose addresses
3931 are not looked up till just above added to the host list. */
3932
3933 nexthost = host->next;
3934
3935 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
3936 domain is in queue_smtp_domains, we don't actually want to attempt any
3937 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
3938 there is a lookup defer in queue_smtp_domains, proceed as if the domain
3939 were not in it. We don't want to hold up all SMTP deliveries! Except when
3940 doing a two-stage queue run, don't do this if forcing. */
3941
3942 if ((!deliver_force || queue_2stage) && (queue_smtp ||
3943 match_isinlist(addrlist->domain,
3944 (const uschar **)&queue_smtp_domains, 0,
3945 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
3946 {
3947 expired = FALSE;
3948 for (addr = addrlist; addr; addr = addr->next)
3949 if (addr->transport_return == DEFER)
3950 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
3951 continue; /* With next host */
3952 }
3953
3954 /* Count hosts being considered - purely for an intelligent comment
3955 if none are usable. */
3956
3957 hosts_total++;
3958
3959 /* Set $host and $host address now in case they are needed for the
3960 interface expansion or the serialize_hosts check; they remain set if an
3961 actual delivery happens. */
3962
3963 deliver_host = host->name;
3964 deliver_host_address = host->address;
3965 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
3966 : host->dnssec == DS_NO ? US"no"
3967 : US"";
3968
3969 /* Set up a string for adding to the retry key if the port number is not
3970 the standard SMTP port. A host may have its own port setting that overrides
3971 the default. */
3972
3973 pistring = string_sprintf(":%d", host->port == PORT_NONE
3974 ? port : host->port);
3975 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
3976
3977 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
3978 string is set, even if constant (as different transports can have different
3979 constant settings), we must add it to the key that is used for retries,
3980 because connections to the same host from a different interface should be
3981 treated separately. */
3982
3983 host_af = Ustrchr(host->address, ':') == NULL ? AF_INET : AF_INET6;
3984 if ((rs = ob->interface) && *rs)
3985 {
3986 if (!smtp_get_interface(rs, host_af, addrlist, &interface, tid))
3987 return FALSE;
3988 pistring = string_sprintf("%s/%s", pistring, interface);
3989 }
3990
3991 /* The first time round the outer loop, check the status of the host by
3992 inspecting the retry data. The second time round, we are interested only
3993 in expired hosts that haven't been tried since this message arrived. */
3994
3995 if (cutoff_retry == 0)
3996 {
3997 BOOL incl_ip;
3998 /* Ensure the status of the address is set by checking retry data if
3999 necessary. There may be host-specific retry data (applicable to all
4000 messages) and also data for retries of a specific message at this host.
4001 If either of these retry records are actually read, the keys used are
4002 returned to save recomputing them later. */
4003
4004 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
4005 US"retry_include_ip_address", ob->retry_include_ip_address,
4006 ob->expand_retry_include_ip_address, &incl_ip) != OK)
4007 continue; /* with next host */
4008
4009 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
4010 incl_ip, &retry_host_key, &retry_message_key);
4011
4012 DEBUG(D_transport) debug_printf("%s [%s]%s retry-status = %s\n", host->name,
4013 (host->address == NULL)? US"" : host->address, pistring,
4014 (host->status == hstatus_usable)? "usable" :
4015 (host->status == hstatus_unusable)? "unusable" :
4016 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
4017
4018 /* Skip this address if not usable at this time, noting if it wasn't
4019 actually expired, both locally and in the address. */
4020
4021 switch (host->status)
4022 {
4023 case hstatus_unusable:
4024 expired = FALSE;
4025 setflag(addrlist, af_retry_skipped);
4026 /* Fall through */
4027
4028 case hstatus_unusable_expired:
4029 switch (host->why)
4030 {
4031 case hwhy_retry: hosts_retry++; break;
4032 case hwhy_failed: hosts_fail++; break;
4033 case hwhy_insecure:
4034 case hwhy_deferred: hosts_defer++; break;
4035 }
4036
4037 /* If there was a retry message key, implying that previously there
4038 was a message-specific defer, we don't want to update the list of
4039 messages waiting for these hosts. */
4040
4041 if (retry_message_key) update_waiting = FALSE;
4042 continue; /* With the next host or IP address */
4043 }
4044 }
4045
4046 /* Second time round the loop: if the address is set but expired, and
4047 the message is newer than the last try, let it through. */
4048
4049 else
4050 {
4051 if ( !host->address
4052 || host->status != hstatus_unusable_expired
4053 || host->last_try > received_time)
4054 continue;
4055 DEBUG(D_transport) debug_printf("trying expired host %s [%s]%s\n",
4056 host->name, host->address, pistring);
4057 host_is_expired = TRUE;
4058 }
4059
4060 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
4061 it remains TRUE only if all hosts are expired and none are actually tried.
4062 */
4063
4064 expired = FALSE;
4065
4066 /* If this host is listed as one to which access must be serialized,
4067 see if another Exim process has a connection to it, and if so, skip
4068 this host. If not, update the database to record our connection to it
4069 and remember this for later deletion. Do not do any of this if we are
4070 sending the message down a pre-existing connection. */
4071
4072 if ( !continue_hostname
4073 && verify_check_given_host(&ob->serialize_hosts, host) == OK)
4074 {
4075 serialize_key = string_sprintf("host-serialize-%s", host->name);
4076 if (!enq_start(serialize_key, 1))
4077 {
4078 DEBUG(D_transport)
4079 debug_printf("skipping host %s because another Exim process "
4080 "is connected to it\n", host->name);
4081 hosts_serial++;
4082 continue;
4083 }
4084 }
4085
4086 /* OK, we have an IP address that is not waiting for its retry time to
4087 arrive (it might be expired) OR (second time round the loop) we have an
4088 expired host that hasn't been tried since the message arrived. Have a go
4089 at delivering the message to it. First prepare the addresses by flushing
4090 out the result of previous attempts, and finding the first address that
4091 is still to be delivered. */
4092
4093 first_addr = prepare_addresses(addrlist, host);
4094
4095 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
4096 message_id, host->name, host->address, addrlist->address,
4097 addrlist->next ? ", ..." : "");
4098
4099 set_process_info("delivering %s to %s [%s] (%s%s)",
4100 message_id, host->name, host->address, addrlist->address,
4101 addrlist->next ? ", ..." : "");
4102
4103 /* This is not for real; don't do the delivery. If there are
4104 any remaining hosts, list them. */
4105
4106 if (dont_deliver)
4107 {
4108 host_item *host2;
4109 set_errno_nohost(addrlist, 0, NULL, OK, FALSE);
4110 for (addr = addrlist; addr; addr = addr->next)
4111 {
4112 addr->host_used = host;
4113 addr->special_action = '*';
4114 addr->message = US"delivery bypassed by -N option";
4115 }
4116 DEBUG(D_transport)
4117 {
4118 debug_printf("*** delivery by %s transport bypassed by -N option\n"
4119 "*** host and remaining hosts:\n", tblock->name);
4120 for (host2 = host; host2; host2 = host2->next)
4121 debug_printf(" %s [%s]\n", host2->name,
4122 host2->address ? host2->address : US"unset");
4123 }
4124 rc = OK;
4125 }
4126
4127 /* This is for real. If the host is expired, we don't count it for
4128 hosts_max_retry. This ensures that all hosts must expire before an address
4129 is timed out, unless hosts_max_try_hardlimit (which protects against
4130 lunatic DNS configurations) is reached.
4131
4132 If the host is not expired and we are about to hit the hosts_max_retry
4133 limit, check to see if there is a subsequent hosts with a different MX
4134 value. If so, make that the next host, and don't count this one. This is a
4135 heuristic to make sure that different MXs do get tried. With a normal kind
4136 of retry rule, they would get tried anyway when the earlier hosts were
4137 delayed, but if the domain has a "retry every time" type of rule - as is
4138 often used for the the very large ISPs, that won't happen. */
4139
4140 else
4141 {
4142 host_item * thost;
4143 /* Make a copy of the host if it is local to this invocation
4144 of the transport. */
4145
4146 if (expanded_hosts)
4147 {
4148 thost = store_get(sizeof(host_item));
4149 *thost = *host;
4150 thost->name = string_copy(host->name);
4151 thost->address = string_copy(host->address);
4152 }
4153 else
4154 thost = host;
4155
4156 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
4157 {
4158 host_item *h;
4159 DEBUG(D_transport)
4160 debug_printf("hosts_max_try limit reached with this host\n");
4161 for (h = host; h; h = h->next) if (h->mx != host->mx)
4162 {
4163 nexthost = h;
4164 unexpired_hosts_tried--;
4165 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
4166 "and will be tried\n");
4167 break;
4168 }
4169 }
4170
4171 /* Attempt the delivery. */
4172
4173 total_hosts_tried++;
4174 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
4175 &message_defer, FALSE);
4176
4177 /* Yield is one of:
4178 OK => connection made, each address contains its result;
4179 message_defer is set for message-specific defers (when all
4180 recipients are marked defer)
4181 DEFER => there was a non-message-specific delivery problem;
4182 ERROR => there was a problem setting up the arguments for a filter,
4183 or there was a problem with expanding added headers
4184 */
4185
4186 /* If the result is not OK, there was a non-message-specific problem.
4187 If the result is DEFER, we need to write to the logs saying what happened
4188 for this particular host, except in the case of authentication and TLS
4189 failures, where the log has already been written. If all hosts defer a
4190 general message is written at the end. */
4191
4192 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL
4193 && first_addr->basic_errno != ERRNO_TLSFAILURE)
4194 write_logs(first_addr, host);
4195
4196 #ifndef DISABLE_EVENT
4197 if (rc == DEFER)
4198 deferred_event_raise(first_addr, host);
4199 #endif
4200
4201 /* If STARTTLS was accepted, but there was a failure in setting up the
4202 TLS session (usually a certificate screwup), and the host is not in
4203 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
4204 TLS forcibly turned off. We have to start from scratch with a new SMTP
4205 connection. That's why the retry is done from here, not from within
4206 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
4207 session, so the in-clear transmission after those errors, if permitted,
4208 happens inside smtp_deliver().] */
4209
4210 #ifdef SUPPORT_TLS
4211 if ( rc == DEFER
4212 && first_addr->basic_errno == ERRNO_TLSFAILURE
4213 && ob->tls_tempfail_tryclear
4214 && verify_check_given_host(&ob->hosts_require_tls, host) != OK
4215 )
4216 {
4217 log_write(0, LOG_MAIN,
4218 "%s: delivering unencrypted to H=%s [%s] (not in hosts_require_tls)",
4219 first_addr->message, host->name, host->address);
4220 first_addr = prepare_addresses(addrlist, host);
4221 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
4222 &message_defer, TRUE);
4223 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
4224 write_logs(first_addr, host);
4225 # ifndef DISABLE_EVENT
4226 if (rc == DEFER)
4227 deferred_event_raise(first_addr, host);
4228 # endif
4229 }
4230 #endif /*SUPPORT_TLS*/
4231 }
4232
4233 /* Delivery attempt finished */
4234
4235 rs = rc == OK ? US"OK"
4236 : rc == DEFER ? US"DEFER"
4237 : rc == ERROR ? US"ERROR"
4238 : US"?";
4239
4240 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
4241 message_id, host->name, host->address, addrlist->address,
4242 addrlist->next ? " (& others)" : "", rs);
4243
4244 /* Release serialization if set up */
4245
4246 if (serialize_key) enq_end(serialize_key);
4247
4248 /* If the result is DEFER, or if a host retry record is known to exist, we
4249 need to add an item to the retry chain for updating the retry database
4250 at the end of delivery. We only need to add the item to the top address,
4251 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
4252 for any other delivery attempts using the same address. (It is copied into
4253 the unusable tree at the outer level, so even if different address blocks
4254 contain the same address, it still won't get tried again.) */
4255
4256 if (rc == DEFER || retry_host_key)
4257 {
4258 int delete_flag = rc != DEFER ? rf_delete : 0;
4259 if (!retry_host_key)
4260 {
4261 BOOL incl_ip;
4262 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
4263 US"retry_include_ip_address", ob->retry_include_ip_address,
4264 ob->expand_retry_include_ip_address, &incl_ip) != OK)
4265 incl_ip = TRUE; /* error; use most-specific retry record */
4266
4267 retry_host_key = incl_ip
4268 ? string_sprintf("T:%S:%s%s", host->name, host->address, pistring)
4269 : string_sprintf("T:%S%s", host->name, pistring);
4270 }
4271
4272 /* If a delivery of another message over an existing SMTP connection
4273 yields DEFER, we do NOT set up retry data for the host. This covers the
4274 case when there are delays in routing the addresses in the second message
4275 that are so long that the server times out. This is alleviated by not
4276 routing addresses that previously had routing defers when handling an
4277 existing connection, but even so, this case may occur (e.g. if a
4278 previously happily routed address starts giving routing defers). If the
4279 host is genuinely down, another non-continued message delivery will
4280 notice it soon enough. */
4281
4282 if (delete_flag != 0 || !continue_hostname)
4283 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
4284
4285 /* We may have tried an expired host, if its retry time has come; ensure
4286 the status reflects the expiry for the benefit of any other addresses. */
4287
4288 if (rc == DEFER)
4289 {
4290 host->status = host_is_expired
4291 ? hstatus_unusable_expired : hstatus_unusable;
4292 host->why = hwhy_deferred;
4293 }
4294 }
4295
4296 /* If message_defer is set (host was OK, but every recipient got deferred
4297 because of some message-specific problem), or if that had happened
4298 previously so that a message retry key exists, add an appropriate item
4299 to the retry chain. Note that if there was a message defer but now there is
4300 a host defer, the message defer record gets deleted. That seems perfectly
4301 reasonable. Also, stop the message from being remembered as waiting
4302 for specific hosts. */
4303
4304 if (message_defer || retry_message_key)
4305 {
4306 int delete_flag = message_defer ? 0 : rf_delete;
4307 if (!retry_message_key)
4308 {
4309 BOOL incl_ip;
4310 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
4311 US"retry_include_ip_address", ob->retry_include_ip_address,
4312 ob->expand_retry_include_ip_address, &incl_ip) != OK)
4313 incl_ip = TRUE; /* error; use most-specific retry record */
4314
4315 retry_message_key = incl_ip
4316 ? string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
4317 message_id)
4318 : string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
4319 }
4320 retry_add_item(addrlist, retry_message_key,
4321 rf_message | rf_host | delete_flag);
4322 update_waiting = FALSE;
4323 }
4324
4325 /* Any return other than DEFER (that is, OK or ERROR) means that the
4326 addresses have got their final statuses filled in for this host. In the OK
4327 case, see if any of them are deferred. */
4328
4329 if (rc == OK)
4330 for (addr = addrlist; addr; addr = addr->next)
4331 if (addr->transport_return == DEFER)
4332 {
4333 some_deferred = TRUE;
4334 break;
4335 }
4336
4337 /* If no addresses deferred or the result was ERROR, return. We do this for
4338 ERROR because a failing filter set-up or add_headers expansion is likely to
4339 fail for any host we try. */
4340
4341 if (rc == ERROR || (rc == OK && !some_deferred))
4342 {
4343 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
4344 return TRUE; /* Each address has its status */
4345 }
4346
4347 /* If the result was DEFER or some individual addresses deferred, let
4348 the loop run to try other hosts with the deferred addresses, except for the
4349 case when we were trying to deliver down an existing channel and failed.
4350 Don't try any other hosts in this case. */
4351
4352 if (continue_hostname) break;
4353
4354 /* If the whole delivery, or some individual addresses, were deferred and
4355 there are more hosts that could be tried, do not count this host towards
4356 the hosts_max_try limit if the age of the message is greater than the
4357 maximum retry time for this host. This means we may try try all hosts,
4358 ignoring the limit, when messages have been around for some time. This is
4359 important because if we don't try all hosts, the address will never time
4360 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
4361
4362 if ((rc == DEFER || some_deferred) && nexthost)
4363 {
4364 BOOL timedout;
4365 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
4366
4367 if (retry && retry->rules)
4368 {
4369 retry_rule *last_rule;
4370 for (last_rule = retry->rules;
4371 last_rule->next;
4372 last_rule = last_rule->next);
4373 timedout = time(NULL) - received_time > last_rule->timeout;
4374 }
4375 else timedout = TRUE; /* No rule => timed out */
4376
4377 if (timedout)
4378 {
4379 unexpired_hosts_tried--;
4380 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
4381 "hosts_max_try (message older than host's retry time)\n");
4382 }
4383 }
4384 } /* End of loop for trying multiple hosts. */
4385
4386 /* This is the end of the loop that repeats iff expired is TRUE and
4387 ob->delay_after_cutoff is FALSE. The second time round we will
4388 try those hosts that haven't been tried since the message arrived. */
4389
4390 DEBUG(D_transport)
4391 {
4392 debug_printf("all IP addresses skipped or deferred at least one address\n");
4393 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
4394 debug_printf("retrying IP addresses not tried since message arrived\n");
4395 }
4396 }
4397
4398
4399 /* Get here if all IP addresses are skipped or defer at least one address. In
4400 MUA wrapper mode, this will happen only for connection or other non-message-
4401 specific failures. Force the delivery status for all addresses to FAIL. */
4402
4403 if (mua_wrapper)
4404 {
4405 for (addr = addrlist; addr; addr = addr->next)
4406 addr->transport_return = FAIL;
4407 goto END_TRANSPORT;
4408 }
4409
4410 /* In the normal, non-wrapper case, add a standard message to each deferred
4411 address if there hasn't been an error, that is, if it hasn't actually been
4412 tried this time. The variable "expired" will be FALSE if any deliveries were
4413 actually tried, or if there was at least one host that was not expired. That
4414 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
4415 a delivery has been tried, an error code will be set, and the failing of the
4416 message is handled by the retry code later.
4417
4418 If queue_smtp is set, or this transport was called to send a subsequent message
4419 down an existing TCP/IP connection, and something caused the host not to be
4420 found, we end up here, but can detect these cases and handle them specially. */
4421
4422 for (addr = addrlist; addr; addr = addr->next)
4423 {
4424 /* If host is not NULL, it means that we stopped processing the host list
4425 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
4426 means we need to behave as if some hosts were skipped because their retry
4427 time had not come. Specifically, this prevents the address from timing out.
4428 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
4429 hosts were tried. */
4430
4431 if (host)
4432 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
4433 {
4434 DEBUG(D_transport)
4435 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
4436 "hosts were tried\n");
4437 }
4438 else
4439 {
4440 DEBUG(D_transport)
4441 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
4442 setflag(addr, af_retry_skipped);
4443 }
4444
4445 if (queue_smtp) /* no deliveries attempted */
4446 {
4447 addr->transport_return = DEFER;
4448 addr->basic_errno = 0;
4449 addr->message = US"SMTP delivery explicitly queued";
4450 }
4451
4452 else if ( addr->transport_return == DEFER
4453 && (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0)
4454 && !addr->message
4455 )
4456 {
4457 addr->basic_errno = ERRNO_HRETRY;
4458 if (continue_hostname)
4459 addr->message = US"no host found for existing SMTP connection";
4460 else if (expired)
4461 {
4462 setflag(addr, af_pass_message); /* This is not a security risk */
4463 addr->message = string_sprintf(
4464 "all hosts%s have been failing for a long time %s",
4465 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"",
4466 ob->delay_after_cutoff
4467 ? US"(and retry time not reached)"
4468 : US"and were last tried after this message arrived");
4469
4470 /* If we are already using fallback hosts, or there are no fallback hosts
4471 defined, convert the result to FAIL to cause a bounce. */
4472
4473 if (addr->host_list == addr->fallback_hosts || !addr->fallback_hosts)
4474 addr->transport_return = FAIL;
4475 }
4476 else
4477 {
4478 const char * s;
4479 if (hosts_retry == hosts_total)
4480 s = "retry time not reached for any host%s";
4481 else if (hosts_fail == hosts_total)
4482 s = "all host address lookups%s failed permanently";
4483 else if (hosts_defer == hosts_total)
4484 s = "all host address lookups%s failed temporarily";
4485 else if (hosts_serial == hosts_total)
4486 s = "connection limit reached for all hosts%s";
4487 else if (hosts_fail+hosts_defer == hosts_total)
4488 s = "all host address lookups%s failed";
4489 else
4490 s = "some host address lookups failed and retry time "
4491 "not reached for other hosts or connection limit reached%s";
4492
4493 addr->message = string_sprintf(s,
4494 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"");
4495 }
4496 }
4497 }
4498
4499 /* Update the database which keeps information about which messages are waiting
4500 for which hosts to become available. For some message-specific errors, the
4501 update_waiting flag is turned off because we don't want follow-on deliveries in
4502 those cases. If this transport instance is explicitly limited to one message
4503 per connection then follow-on deliveries are not possible and there's no need
4504 to create/update the per-transport wait-<transport_name> database. */
4505
4506 if (update_waiting && tblock->connection_max_messages != 1)
4507 transport_update_waiting(hostlist, tblock->name);
4508
4509 END_TRANSPORT:
4510
4511 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
4512
4513 return TRUE; /* Each address has its status */
4514 }
4515
4516 /* vi: aw ai sw=2
4517 */
4518 /* End of transport/smtp.c */