tidying
[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 #ifdef SUPPORT_TLS
224 NULL, /* hosts_nopass_tls */
225 US"*", /* hosts_noproxy_tls */
226 #endif
227 5*60, /* command_timeout */
228 5*60, /* connect_timeout; shorter system default overrides */
229 5*60, /* data timeout */
230 10*60, /* final timeout */
231 1024, /* size_addition */
232 5, /* hosts_max_try */
233 50, /* hosts_max_try_hardlimit */
234 TRUE, /* address_retry_include_sender */
235 FALSE, /* allow_localhost */
236 FALSE, /* authenticated_sender_force */
237 FALSE, /* gethostbyname */
238 TRUE, /* dns_qualify_single */
239 FALSE, /* dns_search_parents */
240 { NULL, NULL }, /* dnssec_domains {request,require} */
241 TRUE, /* delay_after_cutoff */
242 FALSE, /* hosts_override */
243 FALSE, /* hosts_randomize */
244 TRUE, /* keepalive */
245 FALSE, /* lmtp_ignore_quota */
246 NULL, /* expand_retry_include_ip_address */
247 TRUE /* retry_include_ip_address */
248 #ifdef SUPPORT_SOCKS
249 ,NULL /* socks_proxy */
250 #endif
251 #ifdef SUPPORT_TLS
252 ,NULL, /* tls_certificate */
253 NULL, /* tls_crl */
254 NULL, /* tls_privatekey */
255 NULL, /* tls_require_ciphers */
256 NULL, /* tls_sni */
257 US"system", /* tls_verify_certificates */
258 EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
259 /* tls_dh_min_bits */
260 TRUE, /* tls_tempfail_tryclear */
261 NULL, /* tls_verify_hosts */
262 US"*", /* tls_try_verify_hosts */
263 US"*" /* tls_verify_cert_hostnames */
264 #endif
265 #ifndef DISABLE_DKIM
266 , {NULL, /* dkim_canon */
267 NULL, /* dkim_domain */
268 NULL, /* dkim_private_key */
269 NULL, /* dkim_selector */
270 NULL, /* dkim_sign_headers */
271 NULL, /* dkim_strict */
272 FALSE} /* dot_stuffed */
273 #endif
274 };
275
276 /* some DSN flags for use later */
277
278 static int rf_list[] = {rf_notify_never, rf_notify_success,
279 rf_notify_failure, rf_notify_delay };
280
281 static uschar *rf_names[] = { US"NEVER", US"SUCCESS", US"FAILURE", US"DELAY" };
282
283
284
285 /* Local statics */
286
287 static uschar *smtp_command; /* Points to last cmd for error messages */
288 static uschar *mail_command; /* Points to MAIL cmd for error messages */
289 static uschar *data_command = US""; /* Points to DATA cmd for error messages */
290 static BOOL update_waiting; /* TRUE to update the "wait" database */
291
292 /*XXX move to smtp_context */
293 static BOOL pipelining_active; /* current transaction is in pipe mode */
294
295
296 /*************************************************
297 * Setup entry point *
298 *************************************************/
299
300 /* This function is called when the transport is about to be used,
301 but before running it in a sub-process. It is used for two things:
302
303 (1) To set the fallback host list in addresses, when delivering.
304 (2) To pass back the interface, port, protocol, and other options, for use
305 during callout verification.
306
307 Arguments:
308 tblock pointer to the transport instance block
309 addrlist list of addresses about to be transported
310 tf if not NULL, pointer to block in which to return options
311 uid the uid that will be set (not used)
312 gid the gid that will be set (not used)
313 errmsg place for error message (not used)
314
315 Returns: OK always (FAIL, DEFER not used)
316 */
317
318 static int
319 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
320 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
321 {
322 smtp_transport_options_block *ob =
323 (smtp_transport_options_block *)(tblock->options_block);
324
325 errmsg = errmsg; /* Keep picky compilers happy */
326 uid = uid;
327 gid = gid;
328
329 /* Pass back options if required. This interface is getting very messy. */
330
331 if (tf)
332 {
333 tf->interface = ob->interface;
334 tf->port = ob->port;
335 tf->protocol = ob->protocol;
336 tf->hosts = ob->hosts;
337 tf->hosts_override = ob->hosts_override;
338 tf->hosts_randomize = ob->hosts_randomize;
339 tf->gethostbyname = ob->gethostbyname;
340 tf->qualify_single = ob->dns_qualify_single;
341 tf->search_parents = ob->dns_search_parents;
342 tf->helo_data = ob->helo_data;
343 }
344
345 /* Set the fallback host list for all the addresses that don't have fallback
346 host lists, provided that the local host wasn't present in the original host
347 list. */
348
349 if (!testflag(addrlist, af_local_host_removed))
350 for (; addrlist; addrlist = addrlist->next)
351 if (!addrlist->fallback_hosts) addrlist->fallback_hosts = ob->fallback_hostlist;
352
353 return OK;
354 }
355
356
357
358 /*************************************************
359 * Initialization entry point *
360 *************************************************/
361
362 /* Called for each instance, after its options have been read, to
363 enable consistency checks to be done, or anything else that needs
364 to be set up.
365
366 Argument: pointer to the transport instance block
367 Returns: nothing
368 */
369
370 void
371 smtp_transport_init(transport_instance *tblock)
372 {
373 smtp_transport_options_block *ob =
374 (smtp_transport_options_block *)(tblock->options_block);
375
376 /* Retry_use_local_part defaults FALSE if unset */
377
378 if (tblock->retry_use_local_part == TRUE_UNSET)
379 tblock->retry_use_local_part = FALSE;
380
381 /* Set the default port according to the protocol */
382
383 if (ob->port == NULL)
384 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
385 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
386
387 /* Set up the setup entry point, to be called before subprocesses for this
388 transport. */
389
390 tblock->setup = smtp_transport_setup;
391
392 /* Complain if any of the timeouts are zero. */
393
394 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
395 ob->final_timeout <= 0)
396 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
397 "command, data, or final timeout value is zero for %s transport",
398 tblock->name);
399
400 /* If hosts_override is set and there are local hosts, set the global
401 flag that stops verify from showing router hosts. */
402
403 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
404
405 /* If there are any fallback hosts listed, build a chain of host items
406 for them, but do not do any lookups at this time. */
407
408 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
409 }
410
411
412
413
414
415 /*************************************************
416 * Set delivery info into all active addresses *
417 *************************************************/
418
419 /* Only addresses whose status is >= PENDING are relevant. A lesser
420 status means that an address is not currently being processed.
421
422 Arguments:
423 addrlist points to a chain of addresses
424 errno_value to put in each address's errno field
425 msg to put in each address's message field
426 rc to put in each address's transport_return field
427 pass_message if TRUE, set the "pass message" flag in the address
428 host if set, mark addrs as having used this host
429 smtp_greeting from peer
430 helo_response from peer
431
432 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
433 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
434 this particular type of timeout.
435
436 Returns: nothing
437 */
438
439 static void
440 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
441 BOOL pass_message, host_item * host
442 #ifdef EXPERIMENTAL_DSN_INFO
443 , const uschar * smtp_greeting, const uschar * helo_response
444 #endif
445 )
446 {
447 address_item *addr;
448 int orvalue = 0;
449 if (errno_value == ERRNO_CONNECTTIMEOUT)
450 {
451 errno_value = ETIMEDOUT;
452 orvalue = RTEF_CTOUT;
453 }
454 for (addr = addrlist; addr; addr = addr->next)
455 if (addr->transport_return >= PENDING)
456 {
457 addr->basic_errno = errno_value;
458 addr->more_errno |= orvalue;
459 if (msg)
460 {
461 addr->message = msg;
462 if (pass_message) setflag(addr, af_pass_message);
463 }
464 addr->transport_return = rc;
465 if (host)
466 {
467 addr->host_used = host;
468 #ifdef EXPERIMENTAL_DSN_INFO
469 if (smtp_greeting)
470 {uschar * s = Ustrchr(smtp_greeting, '\n'); if (s) *s = '\0';}
471 addr->smtp_greeting = smtp_greeting;
472
473 if (helo_response)
474 {uschar * s = Ustrchr(helo_response, '\n'); if (s) *s = '\0';}
475 addr->helo_response = helo_response;
476 #endif
477 }
478 }
479 }
480
481 static void
482 set_errno_nohost(address_item *addrlist, int errno_value, uschar *msg, int rc,
483 BOOL pass_message)
484 {
485 set_errno(addrlist, errno_value, msg, rc, pass_message, NULL
486 #ifdef EXPERIMENTAL_DSN_INFO
487 , NULL, NULL
488 #endif
489 );
490 }
491
492
493 /*************************************************
494 * Check an SMTP response *
495 *************************************************/
496
497 /* This function is given an errno code and the SMTP response buffer
498 to analyse, together with the host identification for generating messages. It
499 sets an appropriate message and puts the first digit of the response code into
500 the yield variable. If no response was actually read, a suitable digit is
501 chosen.
502
503 Arguments:
504 host the current host, to get its name for messages
505 errno_value pointer to the errno value
506 more_errno from the top address for use with ERRNO_FILTER_FAIL
507 buffer the SMTP response buffer
508 yield where to put a one-digit SMTP response code
509 message where to put an error message
510 pass_message set TRUE if message is an SMTP response
511
512 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
513 */
514
515 static BOOL
516 check_response(host_item *host, int *errno_value, int more_errno,
517 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
518 {
519 uschar * pl = pipelining_active ? US"pipelined " : US"";
520 const uschar * s;
521
522 *yield = '4'; /* Default setting is to give a temporary error */
523
524 switch(*errno_value)
525 {
526 case ETIMEDOUT: /* Handle response timeout */
527 *message = US string_sprintf("SMTP timeout after %s%s",
528 pl, smtp_command);
529 if (transport_count > 0)
530 *message = US string_sprintf("%s (%d bytes written)", *message,
531 transport_count);
532 return FALSE;
533
534 case ERRNO_SMTPFORMAT: /* Handle malformed SMTP response */
535 s = string_printing(buffer);
536 while (isspace(*s)) s++;
537 *message = *s == 0
538 ? string_sprintf("Malformed SMTP reply (an empty line) "
539 "in response to %s%s", pl, smtp_command)
540 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
541 pl, smtp_command, s);
542 return FALSE;
543
544 case ERRNO_FILTER_FAIL: /* Handle a failed filter process error;
545 can't send QUIT as we mustn't end the DATA. */
546 *message = string_sprintf("transport filter process failed (%d)%s",
547 more_errno,
548 more_errno == EX_EXECFAILED ? ": unable to execute command" : "");
549 return FALSE;
550
551 case ERRNO_CHHEADER_FAIL: /* Handle a failed add_headers expansion;
552 can't send QUIT as we mustn't end the DATA. */
553 *message =
554 string_sprintf("failed to expand headers_add or headers_remove: %s",
555 expand_string_message);
556 return FALSE;
557
558 case ERRNO_WRITEINCOMPLETE: /* failure to write a complete data block */
559 *message = string_sprintf("failed to write a data block");
560 return FALSE;
561
562 #ifdef SUPPORT_I18N
563 case ERRNO_UTF8_FWD: /* no advertised SMTPUTF8, for international message */
564 *message = US"utf8 support required but not offered for forwarding";
565 DEBUG(D_deliver|D_transport) debug_printf("%s\n", *message);
566 return TRUE;
567 #endif
568 }
569
570 /* Handle error responses from the remote mailer. */
571
572 if (buffer[0] != 0)
573 {
574 *message = string_sprintf("SMTP error from remote mail server after %s%s: "
575 "%s", pl, smtp_command, s = string_printing(buffer));
576 *pass_message = TRUE;
577 *yield = buffer[0];
578 return TRUE;
579 }
580
581 /* No data was read. If there is no errno, this must be the EOF (i.e.
582 connection closed) case, which causes deferral. An explicit connection reset
583 error has the same effect. Otherwise, put the host's identity in the message,
584 leaving the errno value to be interpreted as well. In all cases, we have to
585 assume the connection is now dead. */
586
587 if (*errno_value == 0 || *errno_value == ECONNRESET)
588 {
589 *errno_value = ERRNO_SMTPCLOSED;
590 *message = US string_sprintf("Remote host closed connection "
591 "in response to %s%s", pl, smtp_command);
592 }
593 else
594 *message = US string_sprintf("%s [%s]", host->name, host->address);
595
596 return FALSE;
597 }
598
599
600
601 /*************************************************
602 * Write error message to logs *
603 *************************************************/
604
605 /* This writes to the main log and to the message log.
606
607 Arguments:
608 addr the address item containing error information
609 host the current host
610
611 Returns: nothing
612 */
613
614 static void
615 write_logs(address_item *addr, host_item *host)
616 {
617 uschar * message = LOGGING(outgoing_port)
618 ? string_sprintf("H=%s [%s]:%d", host->name, host->address,
619 host->port == PORT_NONE ? 25 : host->port)
620 : string_sprintf("H=%s [%s]", host->name, host->address);
621
622 if (addr->message)
623 {
624 message = string_sprintf("%s: %s", message, addr->message);
625 if (addr->basic_errno > 0)
626 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
627 log_write(0, LOG_MAIN, "%s", message);
628 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
629 }
630 else
631 {
632 const uschar * s = exim_errstr(addr->basic_errno);
633 log_write(0, LOG_MAIN, "%s %s", message, s);
634 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), message, s);
635 }
636 }
637
638 static void
639 msglog_line(host_item * host, uschar * message)
640 {
641 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
642 host->name, host->address, message);
643 }
644
645
646
647 #ifndef DISABLE_EVENT
648 /*************************************************
649 * Post-defer action *
650 *************************************************/
651
652 /* This expands an arbitrary per-transport string.
653 It might, for example, be used to write to the database log.
654
655 Arguments:
656 addr the address item containing error information
657 host the current host
658
659 Returns: nothing
660 */
661
662 static void
663 deferred_event_raise(address_item *addr, host_item *host)
664 {
665 uschar * action = addr->transport->event_action;
666 const uschar * save_domain;
667 uschar * save_local;
668
669 if (!action)
670 return;
671
672 save_domain = deliver_domain;
673 save_local = deliver_localpart;
674
675 /*XXX would ip & port already be set up? */
676 deliver_host_address = string_copy(host->address);
677 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
678 event_defer_errno = addr->basic_errno;
679
680 router_name = addr->router->name;
681 transport_name = addr->transport->name;
682 deliver_domain = addr->domain;
683 deliver_localpart = addr->local_part;
684
685 (void) event_raise(action, US"msg:host:defer",
686 addr->message
687 ? addr->basic_errno > 0
688 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
689 : string_copy(addr->message)
690 : addr->basic_errno > 0
691 ? string_copy(US strerror(addr->basic_errno))
692 : NULL);
693
694 deliver_localpart = save_local;
695 deliver_domain = save_domain;
696 router_name = transport_name = NULL;
697 }
698 #endif
699
700 /*************************************************
701 * Synchronize SMTP responses *
702 *************************************************/
703
704 /* This function is called from smtp_deliver() to receive SMTP responses from
705 the server, and match them up with the commands to which they relate. When
706 PIPELINING is not in use, this function is called after every command, and is
707 therefore somewhat over-engineered, but it is simpler to use a single scheme
708 that works both with and without PIPELINING instead of having two separate sets
709 of code.
710
711 The set of commands that are buffered up with pipelining may start with MAIL
712 and may end with DATA; in between are RCPT commands that correspond to the
713 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
714 etc.) are never buffered.
715
716 Errors after MAIL or DATA abort the whole process leaving the response in the
717 buffer. After MAIL, pending responses are flushed, and the original command is
718 re-instated in big_buffer for error messages. For RCPT commands, the remote is
719 permitted to reject some recipient addresses while accepting others. However
720 certain errors clearly abort the whole process. Set the value in
721 transport_return to PENDING_OK if the address is accepted. If there is a
722 subsequent general error, it will get reset accordingly. If not, it will get
723 converted to OK at the end.
724
725 Arguments:
726 sx smtp connection context
727 count the number of responses to read
728 pending_DATA 0 if last command sent was not DATA
729 +1 if previously had a good recipient
730 -1 if not previously had a good recipient
731
732 Returns: 3 if at least one address had 2xx and one had 5xx
733 2 if at least one address had 5xx but none had 2xx
734 1 if at least one host had a 2xx response, but none had 5xx
735 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
736 -1 timeout while reading RCPT response
737 -2 I/O or other non-response error for RCPT
738 -3 DATA or MAIL failed - errno and buffer set
739 */
740
741 static int
742 sync_responses(smtp_context * sx, int count, int pending_DATA)
743 {
744 address_item *addr = sx->sync_addr;
745 smtp_transport_options_block *ob =
746 (smtp_transport_options_block *)sx->tblock->options_block;
747 int yield = 0;
748
749 /* Handle the response for a MAIL command. On error, reinstate the original
750 command in big_buffer for error message use, and flush any further pending
751 responses before returning, except after I/O errors and timeouts. */
752
753 if (sx->pending_MAIL)
754 {
755 count--;
756 if (!smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
757 '2', ob->command_timeout))
758 {
759 DEBUG(D_transport) debug_printf("bad response for MAIL\n");
760 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
761 if (errno == 0 && sx->buffer[0] != 0)
762 {
763 uschar flushbuffer[4096];
764 int save_errno = 0;
765 if (sx->buffer[0] == '4')
766 {
767 save_errno = ERRNO_MAIL4XX;
768 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
769 }
770 while (count-- > 0)
771 {
772 if (!smtp_read_response(&sx->inblock, flushbuffer, sizeof(flushbuffer),
773 '2', ob->command_timeout)
774 && (errno != 0 || flushbuffer[0] == 0))
775 break;
776 }
777 errno = save_errno;
778 }
779
780 if (pending_DATA) count--; /* Number of RCPT responses to come */
781 while (count-- > 0) /* Mark any pending addrs with the host used */
782 {
783 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
784 addr->host_used = sx->host;
785 addr = addr->next;
786 }
787 return -3;
788 }
789 }
790
791 if (pending_DATA) count--; /* Number of RCPT responses to come */
792
793 /* Read and handle the required number of RCPT responses, matching each one up
794 with an address by scanning for the next address whose status is PENDING_DEFER.
795 */
796
797 while (count-- > 0)
798 {
799 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
800
801 /* The address was accepted */
802 addr->host_used = sx->host;
803
804 if (smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
805 '2', ob->command_timeout))
806 {
807 yield |= 1;
808 addr->transport_return = PENDING_OK;
809
810 /* If af_dr_retry_exists is set, there was a routing delay on this address;
811 ensure that any address-specific retry record is expunged. We do this both
812 for the basic key and for the version that also includes the sender. */
813
814 if (testflag(addr, af_dr_retry_exists))
815 {
816 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
817 sender_address);
818 retry_add_item(addr, altkey, rf_delete);
819 retry_add_item(addr, addr->address_retry_key, rf_delete);
820 }
821 }
822
823 /* Timeout while reading the response */
824
825 else if (errno == ETIMEDOUT)
826 {
827 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
828 transport_rcpt_address(addr, sx->tblock->rcpt_include_affixes));
829 set_errno_nohost(sx->first_addr, ETIMEDOUT, message, DEFER, FALSE);
830 retry_add_item(addr, addr->address_retry_key, 0);
831 update_waiting = FALSE;
832 return -1;
833 }
834
835 /* Handle other errors in obtaining an SMTP response by returning -1. This
836 will cause all the addresses to be deferred. Restore the SMTP command in
837 big_buffer for which we are checking the response, so the error message
838 makes sense. */
839
840 else if (errno != 0 || sx->buffer[0] == 0)
841 {
842 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
843 transport_rcpt_address(addr, sx->tblock->rcpt_include_affixes));
844 return -2;
845 }
846
847 /* Handle SMTP permanent and temporary response codes. */
848
849 else
850 {
851 addr->message =
852 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
853 "%s", transport_rcpt_address(addr, sx->tblock->rcpt_include_affixes),
854 string_printing(sx->buffer));
855 setflag(addr, af_pass_message);
856 if (!sx->verify)
857 msglog_line(sx->host, addr->message);
858
859 /* The response was 5xx */
860
861 if (sx->buffer[0] == '5')
862 {
863 addr->transport_return = FAIL;
864 yield |= 2;
865 }
866
867 /* The response was 4xx */
868
869 else
870 {
871 addr->transport_return = DEFER;
872 addr->basic_errno = ERRNO_RCPT4XX;
873 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
874
875 if (!sx->verify)
876 {
877 #ifndef DISABLE_EVENT
878 event_defer_errno = addr->more_errno;
879 msg_event_raise(US"msg:rcpt:host:defer", addr);
880 #endif
881
882 /* Log temporary errors if there are more hosts to be tried.
883 If not, log this last one in the == line. */
884
885 if (sx->host->next)
886 log_write(0, LOG_MAIN, "H=%s [%s]: %s",
887 sx->host->name, sx->host->address, addr->message);
888
889 #ifndef DISABLE_EVENT
890 else
891 msg_event_raise(US"msg:rcpt:defer", addr);
892 #endif
893
894 /* Do not put this message on the list of those waiting for specific
895 hosts, as otherwise it is likely to be tried too often. */
896
897 update_waiting = FALSE;
898
899 /* Add a retry item for the address so that it doesn't get tried again
900 too soon. If address_retry_include_sender is true, add the sender address
901 to the retry key. */
902
903 retry_add_item(addr,
904 ob->address_retry_include_sender
905 ? string_sprintf("%s:<%s>", addr->address_retry_key, sender_address)
906 : addr->address_retry_key,
907 0);
908 }
909 }
910 }
911 } /* Loop for next RCPT response */
912
913 /* Update where to start at for the next block of responses, unless we
914 have already handled all the addresses. */
915
916 if (addr) sx->sync_addr = addr->next;
917
918 /* Handle a response to DATA. If we have not had any good recipients, either
919 previously or in this block, the response is ignored. */
920
921 if (pending_DATA != 0 &&
922 !smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
923 '3', ob->command_timeout))
924 {
925 int code;
926 uschar *msg;
927 BOOL pass_message;
928 if (pending_DATA > 0 || (yield & 1) != 0)
929 {
930 if (errno == 0 && sx->buffer[0] == '4')
931 {
932 errno = ERRNO_DATA4XX;
933 sx->first_addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
934 }
935 return -3;
936 }
937 (void)check_response(sx->host, &errno, 0, sx->buffer, &code, &msg, &pass_message);
938 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
939 "is in use and there were no good recipients\n", msg);
940 }
941
942 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
943 present) received 3xx. If any RCPTs were handled and yielded anything other
944 than 4xx, yield will be set non-zero. */
945
946 return yield;
947 }
948
949
950
951 /* Do the client side of smtp-level authentication */
952 /*
953 Arguments:
954 buffer EHLO response from server (gets overwritten)
955 addrlist chain of potential addresses to deliver
956 host host to deliver to
957 ob transport options
958 ibp, obp comms channel control blocks
959
960 Returns:
961 OK Success, or failed (but not required): global "smtp_authenticated" set
962 DEFER Failed authentication (and was required)
963 ERROR Internal problem
964
965 FAIL_SEND Failed communications - transmit
966 FAIL - response
967 */
968
969 int
970 smtp_auth(uschar *buffer, unsigned bufsize, address_item *addrlist, host_item *host,
971 smtp_transport_options_block *ob, BOOL is_esmtp,
972 smtp_inblock *ibp, smtp_outblock *obp)
973 {
974 int require_auth;
975 uschar *fail_reason = US"server did not advertise AUTH support";
976
977 smtp_authenticated = FALSE;
978 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
979 require_auth = verify_check_given_host(&ob->hosts_require_auth, host);
980
981 if (is_esmtp && !regex_AUTH) regex_AUTH =
982 regex_must_compile(US"\\n250[\\s\\-]AUTH\\s+([\\-\\w\\s]+)(?:\\n|$)",
983 FALSE, TRUE);
984
985 if (is_esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
986 {
987 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
988 expand_nmax = -1; /* reset */
989
990 /* Must not do this check until after we have saved the result of the
991 regex match above. */
992
993 if (require_auth == OK ||
994 verify_check_given_host(&ob->hosts_try_auth, host) == OK)
995 {
996 auth_instance *au;
997 fail_reason = US"no common mechanisms were found";
998
999 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1000
1001 /* Scan the configured authenticators looking for one which is configured
1002 for use as a client, which is not suppressed by client_condition, and
1003 whose name matches an authentication mechanism supported by the server.
1004 If one is found, attempt to authenticate by calling its client function.
1005 */
1006
1007 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1008 {
1009 uschar *p = names;
1010 if (!au->client ||
1011 (au->client_condition != NULL &&
1012 !expand_check_condition(au->client_condition, au->name,
1013 US"client authenticator")))
1014 {
1015 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1016 au->name,
1017 (au->client)? "client_condition is false" :
1018 "not configured as a client");
1019 continue;
1020 }
1021
1022 /* Loop to scan supported server mechanisms */
1023
1024 while (*p != 0)
1025 {
1026 int rc;
1027 int len = Ustrlen(au->public_name);
1028 while (isspace(*p)) p++;
1029
1030 if (strncmpic(au->public_name, p, len) != 0 ||
1031 (p[len] != 0 && !isspace(p[len])))
1032 {
1033 while (*p != 0 && !isspace(*p)) p++;
1034 continue;
1035 }
1036
1037 /* Found data for a listed mechanism. Call its client entry. Set
1038 a flag in the outblock so that data is overwritten after sending so
1039 that reflections don't show it. */
1040
1041 fail_reason = US"authentication attempt(s) failed";
1042 obp->authenticating = TRUE;
1043 rc = (au->info->clientcode)(au, ibp, obp,
1044 ob->command_timeout, buffer, bufsize);
1045 obp->authenticating = FALSE;
1046 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1047 au->name, rc);
1048
1049 /* A temporary authentication failure must hold up delivery to
1050 this host. After a permanent authentication failure, we carry on
1051 to try other authentication methods. If all fail hard, try to
1052 deliver the message unauthenticated unless require_auth was set. */
1053
1054 switch(rc)
1055 {
1056 case OK:
1057 smtp_authenticated = TRUE; /* stops the outer loop */
1058 client_authenticator = au->name;
1059 if (au->set_client_id != NULL)
1060 client_authenticated_id = expand_string(au->set_client_id);
1061 break;
1062
1063 /* Failure after writing a command */
1064
1065 case FAIL_SEND:
1066 return FAIL_SEND;
1067
1068 /* Failure after reading a response */
1069
1070 case FAIL:
1071 if (errno != 0 || buffer[0] != '5') return FAIL;
1072 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1073 au->name, host->name, host->address, buffer);
1074 break;
1075
1076 /* Failure by some other means. In effect, the authenticator
1077 decided it wasn't prepared to handle this case. Typically this
1078 is the result of "fail" in an expansion string. Do we need to
1079 log anything here? Feb 2006: a message is now put in the buffer
1080 if logging is required. */
1081
1082 case CANCELLED:
1083 if (*buffer != 0)
1084 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1085 "authentication H=%s [%s] %s", au->name, host->name,
1086 host->address, buffer);
1087 break;
1088
1089 /* Internal problem, message in buffer. */
1090
1091 case ERROR:
1092 set_errno_nohost(addrlist, ERRNO_AUTHPROB, string_copy(buffer),
1093 DEFER, FALSE);
1094 return ERROR;
1095 }
1096
1097 break; /* If not authenticated, try next authenticator */
1098 } /* Loop for scanning supported server mechanisms */
1099 } /* Loop for further authenticators */
1100 }
1101 }
1102
1103 /* If we haven't authenticated, but are required to, give up. */
1104
1105 if (require_auth == OK && !smtp_authenticated)
1106 {
1107 set_errno_nohost(addrlist, ERRNO_AUTHFAIL,
1108 string_sprintf("authentication required but %s", fail_reason), DEFER,
1109 FALSE);
1110 return DEFER;
1111 }
1112
1113 return OK;
1114 }
1115
1116
1117 /* Construct AUTH appendix string for MAIL TO */
1118 /*
1119 Arguments
1120 buffer to build string
1121 addrlist chain of potential addresses to deliver
1122 ob transport options
1123
1124 Globals smtp_authenticated
1125 client_authenticated_sender
1126 Return True on error, otherwise buffer has (possibly empty) terminated string
1127 */
1128
1129 BOOL
1130 smtp_mail_auth_str(uschar *buffer, unsigned bufsize, address_item *addrlist,
1131 smtp_transport_options_block *ob)
1132 {
1133 uschar *local_authenticated_sender = authenticated_sender;
1134
1135 #ifdef notdef
1136 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n", authenticated_sender, ob->authenticated_sender, smtp_authenticated?"Y":"N");
1137 #endif
1138
1139 if (ob->authenticated_sender != NULL)
1140 {
1141 uschar *new = expand_string(ob->authenticated_sender);
1142 if (new == NULL)
1143 {
1144 if (!expand_string_forcedfail)
1145 {
1146 uschar *message = string_sprintf("failed to expand "
1147 "authenticated_sender: %s", expand_string_message);
1148 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1149 return TRUE;
1150 }
1151 }
1152 else if (new[0] != 0) local_authenticated_sender = new;
1153 }
1154
1155 /* Add the authenticated sender address if present */
1156
1157 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1158 local_authenticated_sender != NULL)
1159 {
1160 string_format(buffer, bufsize, " AUTH=%s",
1161 auth_xtextencode(local_authenticated_sender,
1162 Ustrlen(local_authenticated_sender)));
1163 client_authenticated_sender = string_copy(local_authenticated_sender);
1164 }
1165 else
1166 *buffer= 0;
1167
1168 return FALSE;
1169 }
1170
1171
1172
1173 #ifdef EXPERIMENTAL_DANE
1174 /* Lookup TLSA record for host/port.
1175 Return: OK success with dnssec; DANE mode
1176 DEFER Do not use this host now, may retry later
1177 FAIL_FORCED No TLSA record; DANE not usable
1178 FAIL Do not use this connection
1179 */
1180
1181 int
1182 tlsa_lookup(const host_item * host, dns_answer * dnsa, BOOL dane_required)
1183 {
1184 /* move this out to host.c given the similarity to dns_lookup() ? */
1185 uschar buffer[300];
1186 const uschar * fullname = buffer;
1187
1188 /* TLSA lookup string */
1189 (void)sprintf(CS buffer, "_%d._tcp.%.256s", host->port, host->name);
1190
1191 switch (dns_lookup(dnsa, buffer, T_TLSA, &fullname))
1192 {
1193 case DNS_SUCCEED:
1194 if (!dns_is_secure(dnsa))
1195 {
1196 log_write(0, LOG_MAIN, "DANE error: TLSA lookup not DNSSEC");
1197 return DEFER;
1198 }
1199 return OK;
1200
1201 case DNS_AGAIN:
1202 return DEFER; /* just defer this TLS'd conn */
1203
1204 case DNS_NODATA: /* no TLSA RR for this lookup */
1205 case DNS_NOMATCH: /* no records at all for this lookup */
1206 return dane_required ? FAIL : FAIL_FORCED;
1207
1208 default:
1209 case DNS_FAIL:
1210 return dane_required ? FAIL : DEFER;
1211 }
1212 }
1213 #endif
1214
1215
1216
1217 typedef struct smtp_compare_s
1218 {
1219 uschar *current_sender_address;
1220 struct transport_instance *tblock;
1221 } smtp_compare_t;
1222
1223
1224 /* Create a unique string that identifies this message, it is based on
1225 sender_address, helo_data and tls_certificate if enabled.
1226 */
1227
1228 static uschar *
1229 smtp_local_identity(uschar * sender, struct transport_instance * tblock)
1230 {
1231 address_item * addr1;
1232 uschar * if1 = US"";
1233 uschar * helo1 = US"";
1234 #ifdef SUPPORT_TLS
1235 uschar * tlsc1 = US"";
1236 #endif
1237 uschar * save_sender_address = sender_address;
1238 uschar * local_identity = NULL;
1239 smtp_transport_options_block * ob =
1240 (smtp_transport_options_block *)tblock->options_block;
1241
1242 sender_address = sender;
1243
1244 addr1 = deliver_make_addr (sender, TRUE);
1245 deliver_set_expansions(addr1);
1246
1247 if (ob->interface)
1248 if1 = expand_string(ob->interface);
1249
1250 if (ob->helo_data)
1251 helo1 = expand_string(ob->helo_data);
1252
1253 #ifdef SUPPORT_TLS
1254 if (ob->tls_certificate)
1255 tlsc1 = expand_string(ob->tls_certificate);
1256 local_identity = string_sprintf ("%s^%s^%s", if1, helo1, tlsc1);
1257 #else
1258 local_identity = string_sprintf ("%s^%s", if1, helo1);
1259 #endif
1260
1261 deliver_set_expansions(NULL);
1262 sender_address = save_sender_address;
1263
1264 return local_identity;
1265 }
1266
1267
1268
1269 /* This routine is a callback that is called from transport_check_waiting.
1270 This function will evaluate the incoming message versus the previous
1271 message. If the incoming message is using a different local identity then
1272 we will veto this new message. */
1273
1274 static BOOL
1275 smtp_are_same_identities(uschar * message_id, smtp_compare_t * s_compare)
1276 {
1277 uschar * message_local_identity,
1278 * current_local_identity,
1279 * new_sender_address;
1280
1281 current_local_identity =
1282 smtp_local_identity(s_compare->current_sender_address, s_compare->tblock);
1283
1284 if (!(new_sender_address = deliver_get_sender_address(message_id)))
1285 return 0;
1286
1287 message_local_identity =
1288 smtp_local_identity(new_sender_address, s_compare->tblock);
1289
1290 return Ustrcmp(current_local_identity, message_local_identity) == 0;
1291 }
1292
1293
1294
1295 static uschar
1296 ehlo_response(uschar * buf, uschar checks)
1297 {
1298 size_t bsize = Ustrlen(buf);
1299
1300 #ifdef SUPPORT_TLS
1301 if ( checks & PEER_OFFERED_TLS
1302 && pcre_exec(regex_STARTTLS, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1303 checks &= ~PEER_OFFERED_TLS;
1304 #endif
1305
1306 if ( checks & PEER_OFFERED_IGNQ
1307 && pcre_exec(regex_IGNOREQUOTA, NULL, CS buf, bsize, 0,
1308 PCRE_EOPT, NULL, 0) < 0)
1309 checks &= ~PEER_OFFERED_IGNQ;
1310
1311 if ( checks & PEER_OFFERED_CHUNKING
1312 && pcre_exec(regex_CHUNKING, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1313 checks &= ~PEER_OFFERED_CHUNKING;
1314
1315 #ifndef DISABLE_PRDR
1316 if ( checks & PEER_OFFERED_PRDR
1317 && pcre_exec(regex_PRDR, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1318 checks &= ~PEER_OFFERED_PRDR;
1319 #endif
1320
1321 #ifdef SUPPORT_I18N
1322 if ( checks & PEER_OFFERED_UTF8
1323 && pcre_exec(regex_UTF8, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1324 checks &= ~PEER_OFFERED_UTF8;
1325 #endif
1326
1327 if ( checks & PEER_OFFERED_DSN
1328 && pcre_exec(regex_DSN, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1329 checks &= ~PEER_OFFERED_DSN;
1330
1331 if ( checks & PEER_OFFERED_PIPE
1332 && pcre_exec(regex_PIPELINING, NULL, CS buf, bsize, 0,
1333 PCRE_EOPT, NULL, 0) < 0)
1334 checks &= ~PEER_OFFERED_PIPE;
1335
1336 if ( checks & PEER_OFFERED_SIZE
1337 && pcre_exec(regex_SIZE, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1338 checks &= ~PEER_OFFERED_SIZE;
1339
1340 return checks;
1341 }
1342
1343
1344
1345 /* Callback for emitting a BDAT data chunk header.
1346
1347 If given a nonzero size, first flush any buffered SMTP commands
1348 then emit the command.
1349
1350 Reap previous SMTP command responses if requested, and always reap
1351 the response from a previous BDAT command.
1352
1353 Args:
1354 tctx transport context
1355 chunk_size value for SMTP BDAT command
1356 flags
1357 tc_chunk_last add LAST option to SMTP BDAT command
1358 tc_reap_prev reap response to previous SMTP commands
1359
1360 Returns: OK or ERROR
1361 */
1362
1363 static int
1364 smtp_chunk_cmd_callback(transport_ctx * tctx, unsigned chunk_size,
1365 unsigned flags)
1366 {
1367 smtp_transport_options_block * ob =
1368 (smtp_transport_options_block *)(tctx->tblock->options_block);
1369 smtp_context * sx = tctx->smtp_context;
1370 int cmd_count = 0;
1371 int prev_cmd_count;
1372
1373 /* Write SMTP chunk header command */
1374
1375 if (chunk_size > 0)
1376 {
1377 if((cmd_count = smtp_write_command(&sx->outblock, FALSE, "BDAT %u%s\r\n",
1378 chunk_size,
1379 flags & tc_chunk_last ? " LAST" : "")
1380 ) < 0) return ERROR;
1381 if (flags & tc_chunk_last)
1382 data_command = string_copy(big_buffer); /* Save for later error message */
1383 }
1384
1385 prev_cmd_count = cmd_count += sx->cmd_count;
1386
1387 /* Reap responses for any previous, but not one we just emitted */
1388
1389 if (chunk_size > 0)
1390 prev_cmd_count--;
1391 if (sx->pending_BDAT)
1392 prev_cmd_count--;
1393
1394 if (flags & tc_reap_prev && prev_cmd_count > 0)
1395 {
1396 DEBUG(D_transport) debug_printf("look for %d responses"
1397 " for previous pipelined cmds\n", prev_cmd_count);
1398
1399 switch(sync_responses(sx, prev_cmd_count, 0))
1400 {
1401 case 1: /* 2xx (only) => OK */
1402 case 3: sx->good_RCPT = TRUE; /* 2xx & 5xx => OK & progress made */
1403 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
1404 case 0: break; /* No 2xx or 5xx, but no probs */
1405
1406 case -1: /* Timeout on RCPT */
1407 default: return ERROR; /* I/O error, or any MAIL/DATA error */
1408 }
1409 cmd_count = 1;
1410 if (!sx->pending_BDAT)
1411 pipelining_active = FALSE;
1412 }
1413
1414 /* Reap response for an outstanding BDAT */
1415
1416 if (sx->pending_BDAT)
1417 {
1418 DEBUG(D_transport) debug_printf("look for one response for BDAT\n");
1419
1420 if (!smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer), '2',
1421 ob->command_timeout))
1422 {
1423 if (errno == 0 && sx->buffer[0] == '4')
1424 {
1425 errno = ERRNO_DATA4XX; /*XXX does this actually get used? */
1426 sx->addrlist->more_errno |=
1427 ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1428 }
1429 return ERROR;
1430 }
1431 cmd_count--;
1432 sx->pending_BDAT = FALSE;
1433 pipelining_active = FALSE;
1434 }
1435 else if (chunk_size > 0)
1436 sx->pending_BDAT = TRUE;
1437
1438
1439 sx->cmd_count = cmd_count;
1440 return OK;
1441 }
1442
1443
1444
1445 /*************************************************
1446 * Make connection for given message *
1447 *************************************************/
1448
1449 /*
1450 Arguments:
1451 ctx connection context
1452 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1453 a second attempt after TLS initialization fails
1454
1455 Returns: OK - the connection was made and the delivery attempted;
1456 fd is set in the conn context, tls_out set up.
1457 DEFER - the connection could not be made, or something failed
1458 while setting up the SMTP session, or there was a
1459 non-message-specific error, such as a timeout.
1460 ERROR - helo_data or add_headers or authenticated_sender is
1461 specified for this transport, and the string failed
1462 to expand
1463 */
1464 int
1465 smtp_setup_conn(smtp_context * sx, BOOL suppress_tls)
1466 {
1467 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1468 dns_answer tlsa_dnsa;
1469 #endif
1470 BOOL pass_message = FALSE;
1471 uschar * message = NULL;
1472 int yield = OK;
1473 int rc;
1474
1475 sx->ob = (smtp_transport_options_block *) sx->tblock->options_block;
1476
1477 sx->lmtp = strcmpic(sx->ob->protocol, US"lmtp") == 0;
1478 sx->smtps = strcmpic(sx->ob->protocol, US"smtps") == 0;
1479 sx->ok = FALSE;
1480 sx->send_rset = TRUE;
1481 sx->send_quit = TRUE;
1482 sx->setting_up = TRUE;
1483 sx->esmtp = TRUE;
1484 sx->esmtp_sent = FALSE;
1485 #ifdef SUPPORT_I18N
1486 sx->utf8_needed = FALSE;
1487 #endif
1488 sx->dsn_all_lasthop = TRUE;
1489 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1490 sx->dane = FALSE;
1491 sx->dane_required = verify_check_given_host(&sx->ob->hosts_require_dane, sx->host) == OK;
1492 #endif
1493
1494 if ((sx->max_rcpt = sx->tblock->max_addresses) == 0) sx->max_rcpt = 999999;
1495 sx->peer_offered = 0;
1496 sx->igquotstr = US"";
1497 if (!sx->helo_data) sx->helo_data = sx->ob->helo_data;
1498 #ifdef EXPERIMENTAL_DSN_INFO
1499 sx->smtp_greeting = NULL;
1500 sx->helo_response = NULL;
1501 #endif
1502
1503 smtp_command = US"initial connection";
1504 sx->buffer[0] = '\0';
1505
1506 /* Set up the buffer for reading SMTP response packets. */
1507
1508 sx->inblock.buffer = sx->inbuffer;
1509 sx->inblock.buffersize = sizeof(sx->inbuffer);
1510 sx->inblock.ptr = sx->inbuffer;
1511 sx->inblock.ptrend = sx->inbuffer;
1512
1513 /* Set up the buffer for holding SMTP commands while pipelining */
1514
1515 sx->outblock.buffer = sx->outbuffer;
1516 sx->outblock.buffersize = sizeof(sx->outbuffer);
1517 sx->outblock.ptr = sx->outbuffer;
1518 sx->outblock.cmd_count = 0;
1519 sx->outblock.authenticating = FALSE;
1520
1521 /* Reset the parameters of a TLS session. */
1522
1523 tls_out.bits = 0;
1524 tls_out.cipher = NULL; /* the one we may use for this transport */
1525 tls_out.ourcert = NULL;
1526 tls_out.peercert = NULL;
1527 tls_out.peerdn = NULL;
1528 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1529 tls_out.sni = NULL;
1530 #endif
1531 tls_out.ocsp = OCSP_NOT_REQ;
1532
1533 /* Flip the legacy TLS-related variables over to the outbound set in case
1534 they're used in the context of the transport. Don't bother resetting
1535 afterward (when being used by a transport) as we're in a subprocess.
1536 For verify, unflipped once the callout is dealt with */
1537
1538 tls_modify_variables(&tls_out);
1539
1540 #ifndef SUPPORT_TLS
1541 if (sx->smtps)
1542 {
1543 set_errno_nohost(sx->addrlist, ERRNO_TLSFAILURE, US"TLS support not available",
1544 DEFER, FALSE);
1545 return ERROR;
1546 }
1547 #endif
1548
1549 /* Make a connection to the host if this isn't a continued delivery, and handle
1550 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
1551 specially so they can be identified for retries. */
1552
1553 if (continue_hostname == NULL)
1554 {
1555 if (sx->verify)
1556 HDEBUG(D_verify) debug_printf("interface=%s port=%d\n", sx->interface, sx->port);
1557
1558 /* This puts port into host->port */
1559 sx->inblock.sock = sx->outblock.sock =
1560 smtp_connect(sx->host, sx->host_af, sx->port, sx->interface,
1561 sx->ob->connect_timeout, sx->tblock);
1562
1563 if (sx->inblock.sock < 0)
1564 {
1565 uschar * msg = NULL;
1566 if (sx->verify)
1567 {
1568 msg = US strerror(errno);
1569 HDEBUG(D_verify) debug_printf("connect: %s\n", msg);
1570 }
1571 set_errno_nohost(sx->addrlist,
1572 errno == ETIMEDOUT ? ERRNO_CONNECTTIMEOUT : errno,
1573 sx->verify ? string_sprintf("could not connect: %s", msg)
1574 : NULL,
1575 DEFER, FALSE);
1576 sx->send_quit = FALSE;
1577 return DEFER;
1578 }
1579
1580 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1581 {
1582 tls_out.dane_verified = FALSE;
1583 tls_out.tlsa_usage = 0;
1584
1585 if (sx->host->dnssec == DS_YES)
1586 {
1587 if( sx->dane_required
1588 || verify_check_given_host(&sx->ob->hosts_try_dane, sx->host) == OK
1589 )
1590 switch (rc = tlsa_lookup(sx->host, &tlsa_dnsa, sx->dane_required))
1591 {
1592 case OK: sx->dane = TRUE; break;
1593 case FAIL_FORCED: break;
1594 default: set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
1595 string_sprintf("DANE error: tlsa lookup %s",
1596 rc == DEFER ? "DEFER" : "FAIL"),
1597 rc, FALSE);
1598 return rc;
1599 }
1600 }
1601 else if (sx->dane_required)
1602 {
1603 set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
1604 string_sprintf("DANE error: %s lookup not DNSSEC", sx->host->name),
1605 FAIL, FALSE);
1606 return FAIL;
1607 }
1608
1609 if (sx->dane)
1610 sx->ob->tls_tempfail_tryclear = FALSE;
1611 }
1612 #endif /*DANE*/
1613
1614 /* Expand the greeting message while waiting for the initial response. (Makes
1615 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1616 delayed till here so that $sending_interface and $sending_port are set. */
1617
1618 if (sx->helo_data)
1619 if (!(sx->helo_data = expand_string(sx->helo_data)))
1620 if (sx->verify)
1621 log_write(0, LOG_MAIN|LOG_PANIC,
1622 "<%s>: failed to expand transport's helo_data value for callout: %s",
1623 sx->addrlist->address, expand_string_message);
1624
1625 #ifdef SUPPORT_I18N
1626 if (sx->helo_data)
1627 {
1628 expand_string_message = NULL;
1629 if ((sx->helo_data = string_domain_utf8_to_alabel(sx->helo_data,
1630 &expand_string_message)),
1631 expand_string_message)
1632 if (sx->verify)
1633 log_write(0, LOG_MAIN|LOG_PANIC,
1634 "<%s>: failed to expand transport's helo_data value for callout: %s",
1635 sx->addrlist->address, expand_string_message);
1636 else
1637 sx->helo_data = NULL;
1638 }
1639 #endif
1640
1641 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1642 is nevertheless a reasonably clean way of programming this kind of logic,
1643 where you want to escape on any error. */
1644
1645 if (!sx->smtps)
1646 {
1647 BOOL good_response;
1648
1649 #ifdef TCP_QUICKACK
1650 (void) setsockopt(sx->inblock.sock, IPPROTO_TCP, TCP_QUICKACK, US &off, sizeof(off));
1651 #endif
1652 good_response = smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
1653 '2', sx->ob->command_timeout);
1654 #ifdef EXPERIMENTAL_DSN_INFO
1655 sx->smtp_greeting = string_copy(sx->buffer);
1656 #endif
1657 if (!good_response) goto RESPONSE_FAILED;
1658
1659 #ifndef DISABLE_EVENT
1660 {
1661 uschar * s;
1662 lookup_dnssec_authenticated = sx->host->dnssec==DS_YES ? US"yes"
1663 : sx->host->dnssec==DS_NO ? US"no" : NULL;
1664 s = event_raise(sx->tblock->event_action, US"smtp:connect", sx->buffer);
1665 if (s)
1666 {
1667 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL,
1668 string_sprintf("deferred by smtp:connect event expansion: %s", s),
1669 DEFER, FALSE);
1670 yield = DEFER;
1671 goto SEND_QUIT;
1672 }
1673 }
1674 #endif
1675
1676 /* Now check if the helo_data expansion went well, and sign off cleanly if
1677 it didn't. */
1678
1679 if (!sx->helo_data)
1680 {
1681 message = string_sprintf("failed to expand helo_data: %s",
1682 expand_string_message);
1683 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1684 yield = DEFER;
1685 goto SEND_QUIT;
1686 }
1687 }
1688
1689 /** Debugging without sending a message
1690 sx->addrlist->transport_return = DEFER;
1691 goto SEND_QUIT;
1692 **/
1693
1694 /* Errors that occur after this point follow an SMTP command, which is
1695 left in big_buffer by smtp_write_command() for use in error messages. */
1696
1697 smtp_command = big_buffer;
1698
1699 /* Tell the remote who we are...
1700
1701 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1702 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1703 greeting is of this form. The assumption was that the far end supports it
1704 properly... but experience shows that there are some that give 5xx responses,
1705 even though the banner includes "ESMTP" (there's a bloody-minded one that
1706 says "ESMTP not spoken here"). Cope with that case.
1707
1708 September 2000: Time has passed, and it seems reasonable now to always send
1709 EHLO at the start. It is also convenient to make the change while installing
1710 the TLS stuff.
1711
1712 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1713 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1714 would be no way to send out the mails, so there is now a host list
1715 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1716 PIPELINING problem as well. Maybe it can also be useful to cure other
1717 problems with broken servers.
1718
1719 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1720 Then somebody tried it with a Microsoft mailer... It seems that all other
1721 mailers use upper case for some reason (the RFC is quite clear about case
1722 independence) so, for peace of mind, I gave in. */
1723
1724 sx->esmtp = verify_check_given_host(&sx->ob->hosts_avoid_esmtp, sx->host) != OK;
1725
1726 /* Alas; be careful, since this goto is not an error-out, so conceivably
1727 we might set data between here and the target which we assume to exist
1728 and be usable. I can see this coming back to bite us. */
1729 #ifdef SUPPORT_TLS
1730 if (sx->smtps)
1731 {
1732 smtp_peer_options |= PEER_OFFERED_TLS;
1733 suppress_tls = FALSE;
1734 sx->ob->tls_tempfail_tryclear = FALSE;
1735 smtp_command = US"SSL-on-connect";
1736 goto TLS_NEGOTIATE;
1737 }
1738 #endif
1739
1740 if (sx->esmtp)
1741 {
1742 if (smtp_write_command(&sx->outblock, FALSE, "%s %s\r\n",
1743 sx->lmtp ? "LHLO" : "EHLO", sx->helo_data) < 0)
1744 goto SEND_FAILED;
1745 sx->esmtp_sent = TRUE;
1746 if (!smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer), '2',
1747 sx->ob->command_timeout))
1748 {
1749 if (errno != 0 || sx->buffer[0] == 0 || sx->lmtp)
1750 {
1751 #ifdef EXPERIMENTAL_DSN_INFO
1752 sx->helo_response = string_copy(sx->buffer);
1753 #endif
1754 goto RESPONSE_FAILED;
1755 }
1756 sx->esmtp = FALSE;
1757 }
1758 #ifdef EXPERIMENTAL_DSN_INFO
1759 sx->helo_response = string_copy(sx->buffer);
1760 #endif
1761 }
1762 else
1763 DEBUG(D_transport)
1764 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1765
1766 if (!sx->esmtp)
1767 {
1768 BOOL good_response;
1769 int n = sizeof(sx->buffer);
1770 uschar * rsp = sx->buffer;
1771
1772 if (sx->esmtp_sent && (n = Ustrlen(sx->buffer)) < sizeof(sx->buffer)/2)
1773 { rsp = sx->buffer + n + 1; n = sizeof(sx->buffer) - n; }
1774
1775 if (smtp_write_command(&sx->outblock, FALSE, "HELO %s\r\n", sx->helo_data) < 0)
1776 goto SEND_FAILED;
1777 good_response = smtp_read_response(&sx->inblock, rsp, n,
1778 '2', sx->ob->command_timeout);
1779 #ifdef EXPERIMENTAL_DSN_INFO
1780 sx->helo_response = string_copy(rsp);
1781 #endif
1782 if (!good_response)
1783 {
1784 /* Handle special logging for a closed connection after HELO
1785 when had previously sent EHLO */
1786
1787 if (rsp != sx->buffer && rsp[0] == 0 && (errno == 0 || errno == ECONNRESET))
1788 {
1789 errno = ERRNO_SMTPCLOSED;
1790 goto EHLOHELO_FAILED;
1791 }
1792 Ustrncpy(sx->buffer, rsp, sizeof(sx->buffer)/2);
1793 goto RESPONSE_FAILED;
1794 }
1795 }
1796
1797 sx->peer_offered = smtp_peer_options = 0;
1798
1799 if (sx->esmtp || sx->lmtp)
1800 {
1801 sx->peer_offered = ehlo_response(sx->buffer,
1802 PEER_OFFERED_TLS /* others checked later */
1803 );
1804
1805 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1806
1807 #ifdef SUPPORT_TLS
1808 smtp_peer_options |= sx->peer_offered & PEER_OFFERED_TLS;
1809 #endif
1810 }
1811 }
1812
1813 /* For continuing deliveries down the same channel, having re-exec'd the socket
1814 is the standard input; for a socket held open from verify it is recorded
1815 in the cutthrough context block. Either way we don't need to redo EHLO here
1816 (but may need to do so for TLS - see below).
1817 Set up the pointer to where subsequent commands will be left, for
1818 error messages. Note that smtp_peer_options will have been
1819 set from the command line if they were set in the process that passed the
1820 connection on. */
1821
1822 /*XXX continue case needs to propagate DSN_INFO, prob. in deliver.c
1823 as the continue goes via transport_pass_socket() and doublefork and exec.
1824 It does not wait. Unclear how we keep separate host's responses
1825 separate - we could match up by host ip+port as a bodge. */
1826
1827 else
1828 {
1829 if (cutthrough.fd >= 0 && cutthrough.callout_hold_only)
1830 {
1831 sx->inblock.sock = sx->outblock.sock = cutthrough.fd;
1832 sx->host->port = sx->port = cutthrough.host.port;
1833 }
1834 else
1835 {
1836 sx->inblock.sock = sx->outblock.sock = 0; /* stdin */
1837 sx->host->port = sx->port; /* Record the port that was used */
1838 }
1839 smtp_command = big_buffer;
1840 sx->helo_data = NULL; /* ensure we re-expand ob->helo_data */
1841
1842 /* For a continued connection with TLS being proxied for us, or a
1843 held-open verify connection with TLS, nothing more to do. */
1844
1845 if ( continue_proxy_cipher
1846 || (cutthrough.fd >= 0 && cutthrough.callout_hold_only && cutthrough.is_tls)
1847 )
1848 {
1849 sx->peer_offered = smtp_peer_options;
1850 pipelining_active = !!(smtp_peer_options & PEER_OFFERED_PIPE);
1851 HDEBUG(D_transport) debug_printf("continued connection, %s TLS\n",
1852 continue_proxy_cipher ? "proxied" : "verify conn with");
1853 return OK;
1854 }
1855 HDEBUG(D_transport) debug_printf("continued connection, no TLS\n");
1856 }
1857
1858 /* If TLS is available on this connection, whether continued or not, attempt to
1859 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1860 send another EHLO - the server may give a different answer in secure mode. We
1861 use a separate buffer for reading the response to STARTTLS so that if it is
1862 negative, the original EHLO data is available for subsequent analysis, should
1863 the client not be required to use TLS. If the response is bad, copy the buffer
1864 for error analysis. */
1865
1866 #ifdef SUPPORT_TLS
1867 if ( smtp_peer_options & PEER_OFFERED_TLS
1868 && !suppress_tls
1869 && verify_check_given_host(&sx->ob->hosts_avoid_tls, sx->host) != OK
1870 && ( !sx->verify
1871 || verify_check_given_host(&sx->ob->hosts_verify_avoid_tls, sx->host) != OK
1872 ) )
1873 {
1874 uschar buffer2[4096];
1875 if (smtp_write_command(&sx->outblock, FALSE, "STARTTLS\r\n") < 0)
1876 goto SEND_FAILED;
1877
1878 /* If there is an I/O error, transmission of this message is deferred. If
1879 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1880 false, we also defer. However, if there is a temporary rejection of STARTTLS
1881 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1882 STARTTLS, we carry on. This means we will try to send the message in clear,
1883 unless the host is in hosts_require_tls (tested below). */
1884
1885 if (!smtp_read_response(&sx->inblock, buffer2, sizeof(buffer2), '2',
1886 sx->ob->command_timeout))
1887 {
1888 if ( errno != 0
1889 || buffer2[0] == 0
1890 || (buffer2[0] == '4' && !sx->ob->tls_tempfail_tryclear)
1891 )
1892 {
1893 Ustrncpy(sx->buffer, buffer2, sizeof(sx->buffer));
1894 sx->buffer[sizeof(sx->buffer)-1] = '\0';
1895 goto RESPONSE_FAILED;
1896 }
1897 }
1898
1899 /* STARTTLS accepted: try to negotiate a TLS session. */
1900
1901 else
1902 TLS_NEGOTIATE:
1903 {
1904 address_item * addr;
1905 uschar * errstr;
1906 int rc = tls_client_start(sx->inblock.sock, sx->host, sx->addrlist, sx->tblock,
1907 # ifdef EXPERIMENTAL_DANE
1908 sx->dane ? &tlsa_dnsa : NULL,
1909 # endif
1910 &errstr);
1911
1912 /* TLS negotiation failed; give an error. From outside, this function may
1913 be called again to try in clear on a new connection, if the options permit
1914 it for this host. */
1915
1916 if (rc != OK)
1917 {
1918 # ifdef EXPERIMENTAL_DANE
1919 if (sx->dane) log_write(0, LOG_MAIN,
1920 "DANE attempt failed; TLS connection to %s [%s]: %s",
1921 sx->host->name, sx->host->address, errstr);
1922 # endif
1923
1924 errno = ERRNO_TLSFAILURE;
1925 message = string_sprintf("TLS session: %s", errstr);
1926 sx->send_quit = FALSE;
1927 goto TLS_FAILED;
1928 }
1929
1930 /* TLS session is set up */
1931
1932 smtp_peer_options_wrap = smtp_peer_options;
1933 for (addr = sx->addrlist; addr; addr = addr->next)
1934 if (addr->transport_return == PENDING_DEFER)
1935 {
1936 addr->cipher = tls_out.cipher;
1937 addr->ourcert = tls_out.ourcert;
1938 addr->peercert = tls_out.peercert;
1939 addr->peerdn = tls_out.peerdn;
1940 addr->ocsp = tls_out.ocsp;
1941 }
1942 }
1943 }
1944
1945 /* if smtps, we'll have smtp_command set to something else; always safe to
1946 reset it here. */
1947 smtp_command = big_buffer;
1948
1949 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1950 helo_data is null, we are dealing with a connection that was passed from
1951 another process, and so we won't have expanded helo_data above. We have to
1952 expand it here. $sending_ip_address and $sending_port are set up right at the
1953 start of the Exim process (in exim.c). */
1954
1955 if (tls_out.active >= 0)
1956 {
1957 char *greeting_cmd;
1958 BOOL good_response;
1959
1960 if (!sx->helo_data && !(sx->helo_data = expand_string(sx->ob->helo_data)))
1961 {
1962 uschar *message = string_sprintf("failed to expand helo_data: %s",
1963 expand_string_message);
1964 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1965 yield = DEFER;
1966 goto SEND_QUIT;
1967 }
1968
1969 /* For SMTPS we need to wait for the initial OK response. */
1970 if (sx->smtps)
1971 {
1972 good_response = smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
1973 '2', sx->ob->command_timeout);
1974 #ifdef EXPERIMENTAL_DSN_INFO
1975 sx->smtp_greeting = string_copy(sx->buffer);
1976 #endif
1977 if (!good_response) goto RESPONSE_FAILED;
1978 }
1979
1980 if (sx->esmtp)
1981 greeting_cmd = "EHLO";
1982 else
1983 {
1984 greeting_cmd = "HELO";
1985 DEBUG(D_transport)
1986 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1987 }
1988
1989 if (smtp_write_command(&sx->outblock, FALSE, "%s %s\r\n",
1990 sx->lmtp ? "LHLO" : greeting_cmd, sx->helo_data) < 0)
1991 goto SEND_FAILED;
1992 good_response = smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
1993 '2', sx->ob->command_timeout);
1994 #ifdef EXPERIMENTAL_DSN_INFO
1995 sx->helo_response = string_copy(sx->buffer);
1996 #endif
1997 if (!good_response) goto RESPONSE_FAILED;
1998 smtp_peer_options = 0;
1999 }
2000
2001 /* If the host is required to use a secure channel, ensure that we
2002 have one. */
2003
2004 else if ( sx->smtps
2005 # ifdef EXPERIMENTAL_DANE
2006 || sx->dane
2007 # endif
2008 || verify_check_given_host(&sx->ob->hosts_require_tls, sx->host) == OK
2009 )
2010 {
2011 errno = ERRNO_TLSREQUIRED;
2012 message = string_sprintf("a TLS session is required, but %s",
2013 smtp_peer_options & PEER_OFFERED_TLS
2014 ? "an attempt to start TLS failed" : "the server did not offer TLS support");
2015 goto TLS_FAILED;
2016 }
2017 #endif /*SUPPORT_TLS*/
2018
2019 /* If TLS is active, we have just started it up and re-done the EHLO command,
2020 so its response needs to be analyzed. If TLS is not active and this is a
2021 continued session down a previously-used socket, we haven't just done EHLO, so
2022 we skip this. */
2023
2024 if (continue_hostname == NULL
2025 #ifdef SUPPORT_TLS
2026 || tls_out.active >= 0
2027 #endif
2028 )
2029 {
2030 if (sx->esmtp || sx->lmtp)
2031 {
2032 sx->peer_offered = ehlo_response(sx->buffer,
2033 0 /* no TLS */
2034 | (sx->lmtp && sx->ob->lmtp_ignore_quota ? PEER_OFFERED_IGNQ : 0)
2035 | PEER_OFFERED_CHUNKING
2036 | PEER_OFFERED_PRDR
2037 #ifdef SUPPORT_I18N
2038 | (sx->addrlist->prop.utf8_msg ? PEER_OFFERED_UTF8 : 0)
2039 /*XXX if we hand peercaps on to continued-conn processes,
2040 must not depend on this addr */
2041 #endif
2042 | PEER_OFFERED_DSN
2043 | PEER_OFFERED_PIPE
2044 | (sx->ob->size_addition >= 0 ? PEER_OFFERED_SIZE : 0)
2045 );
2046
2047 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
2048 lmtp_ignore_quota option was set. */
2049
2050 sx->igquotstr = sx->peer_offered & PEER_OFFERED_IGNQ ? US" IGNOREQUOTA" : US"";
2051
2052 /* If the response to EHLO specified support for the SIZE parameter, note
2053 this, provided size_addition is non-negative. */
2054
2055 smtp_peer_options |= sx->peer_offered & PEER_OFFERED_SIZE;
2056
2057 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
2058 the current host, esmtp will be false, so PIPELINING can never be used. If
2059 the current host matches hosts_avoid_pipelining, don't do it. */
2060
2061 if ( sx->peer_offered & PEER_OFFERED_PIPE
2062 && verify_check_given_host(&sx->ob->hosts_avoid_pipelining, sx->host) != OK)
2063 smtp_peer_options |= PEER_OFFERED_PIPE;
2064
2065 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
2066 smtp_peer_options & PEER_OFFERED_PIPE ? "" : "not ");
2067
2068 if ( sx->peer_offered & PEER_OFFERED_CHUNKING
2069 && verify_check_given_host(&sx->ob->hosts_try_chunking, sx->host) != OK)
2070 sx->peer_offered &= ~PEER_OFFERED_CHUNKING;
2071
2072 if (sx->peer_offered & PEER_OFFERED_CHUNKING)
2073 {DEBUG(D_transport) debug_printf("CHUNKING usable\n");}
2074
2075 #ifndef DISABLE_PRDR
2076 if ( sx->peer_offered & PEER_OFFERED_PRDR
2077 && verify_check_given_host(&sx->ob->hosts_try_prdr, sx->host) != OK)
2078 sx->peer_offered &= ~PEER_OFFERED_PRDR;
2079
2080 if (sx->peer_offered & PEER_OFFERED_PRDR)
2081 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
2082 #endif
2083
2084 /* Note if the server supports DSN */
2085 smtp_peer_options |= sx->peer_offered & PEER_OFFERED_DSN;
2086 DEBUG(D_transport) debug_printf("%susing DSN\n",
2087 sx->peer_offered & PEER_OFFERED_DSN ? "" : "not ");
2088
2089 /* Note if the response to EHLO specifies support for the AUTH extension.
2090 If it has, check that this host is one we want to authenticate to, and do
2091 the business. The host name and address must be available when the
2092 authenticator's client driver is running. */
2093
2094 switch (yield = smtp_auth(sx->buffer, sizeof(sx->buffer), sx->addrlist, sx->host,
2095 sx->ob, sx->esmtp, &sx->inblock, &sx->outblock))
2096 {
2097 default: goto SEND_QUIT;
2098 case OK: break;
2099 case FAIL_SEND: goto SEND_FAILED;
2100 case FAIL: goto RESPONSE_FAILED;
2101 }
2102 }
2103 }
2104 pipelining_active = !!(smtp_peer_options & PEER_OFFERED_PIPE);
2105
2106 /* The setting up of the SMTP call is now complete. Any subsequent errors are
2107 message-specific. */
2108
2109 sx->setting_up = FALSE;
2110
2111 #ifdef SUPPORT_I18N
2112 if (sx->addrlist->prop.utf8_msg)
2113 {
2114 sx->utf8_needed = !sx->addrlist->prop.utf8_downcvt
2115 && !sx->addrlist->prop.utf8_downcvt_maybe;
2116 DEBUG(D_transport) if (!sx->utf8_needed)
2117 debug_printf("utf8: %s downconvert\n",
2118 sx->addrlist->prop.utf8_downcvt ? "mandatory" : "optional");
2119 }
2120
2121 /* If this is an international message we need the host to speak SMTPUTF8 */
2122 if (sx->utf8_needed && !(sx->peer_offered & PEER_OFFERED_UTF8))
2123 {
2124 errno = ERRNO_UTF8_FWD;
2125 goto RESPONSE_FAILED;
2126 }
2127 #endif
2128
2129 return OK;
2130
2131
2132 {
2133 int code;
2134
2135 RESPONSE_FAILED:
2136 message = NULL;
2137 sx->send_quit = check_response(sx->host, &errno, sx->addrlist->more_errno,
2138 sx->buffer, &code, &message, &pass_message);
2139 goto FAILED;
2140
2141 SEND_FAILED:
2142 code = '4';
2143 message = US string_sprintf("send() to %s [%s] failed: %s",
2144 sx->host->name, sx->host->address, strerror(errno));
2145 sx->send_quit = FALSE;
2146 goto FAILED;
2147
2148 /* This label is jumped to directly when a TLS negotiation has failed,
2149 or was not done for a host for which it is required. Values will be set
2150 in message and errno, and setting_up will always be true. Treat as
2151 a temporary error. */
2152
2153 EHLOHELO_FAILED:
2154 code = '4';
2155 message = string_sprintf("Remote host closed connection in response to %s"
2156 " (EHLO response was: %s)", smtp_command, sx->buffer);
2157 sx->send_quit = FALSE;
2158 goto FAILED;
2159
2160 #ifdef SUPPORT_TLS
2161 TLS_FAILED:
2162 code = '4';
2163 goto FAILED;
2164 #endif
2165
2166 /* The failure happened while setting up the call; see if the failure was
2167 a 5xx response (this will either be on connection, or following HELO - a 5xx
2168 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
2169 never going to accept them. For other errors during setting up (timeouts or
2170 whatever), defer all addresses, and yield DEFER, so that the host is not
2171 tried again for a while. */
2172
2173 FAILED:
2174 sx->ok = FALSE; /* For when reached by GOTO */
2175
2176 yield = code == '5'
2177 #ifdef SUPPORT_I18N
2178 || errno == ERRNO_UTF8_FWD
2179 #endif
2180 ? FAIL : DEFER;
2181
2182 set_errno(sx->addrlist, errno, message, yield, pass_message, sx->host
2183 #ifdef EXPERIMENTAL_DSN_INFO
2184 , sx->smtp_greeting, sx->helo_response
2185 #endif
2186 );
2187 }
2188
2189
2190 SEND_QUIT:
2191
2192 if (sx->send_quit)
2193 (void)smtp_write_command(&sx->outblock, FALSE, "QUIT\r\n");
2194
2195 #ifdef SUPPORT_TLS
2196 tls_close(FALSE, TRUE);
2197 #endif
2198
2199 /* Close the socket, and return the appropriate value, first setting
2200 works because the NULL setting is passed back to the calling process, and
2201 remote_max_parallel is forced to 1 when delivering over an existing connection,
2202
2203 If all went well and continue_more is set, we shouldn't actually get here if
2204 there are further addresses, as the return above will be taken. However,
2205 writing RSET might have failed, or there may be other addresses whose hosts are
2206 specified in the transports, and therefore not visible at top level, in which
2207 case continue_more won't get set. */
2208
2209 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
2210 if (sx->send_quit)
2211 {
2212 shutdown(sx->outblock.sock, SHUT_WR);
2213 if (fcntl(sx->inblock.sock, F_SETFL, O_NONBLOCK) == 0)
2214 for (rc = 16; read(sx->inblock.sock, sx->inbuffer, sizeof(sx->inbuffer)) > 0 && rc > 0;)
2215 rc--; /* drain socket */
2216 sx->send_quit = FALSE;
2217 }
2218 (void)close(sx->inblock.sock);
2219 sx->inblock.sock = sx->outblock.sock = -1;
2220
2221 #ifndef DISABLE_EVENT
2222 (void) event_raise(sx->tblock->event_action, US"tcp:close", NULL);
2223 #endif
2224
2225 continue_transport = NULL;
2226 continue_hostname = NULL;
2227 return yield;
2228 }
2229
2230
2231
2232
2233 /* Create the string of options that will be appended to the MAIL FROM:
2234 in the connection context buffer */
2235
2236 static int
2237 build_mailcmd_options(smtp_context * sx, address_item * addrlist)
2238 {
2239 uschar * p = sx->buffer;
2240 address_item * addr;
2241 int address_count;
2242
2243 *p = 0;
2244
2245 /* If we know the receiving MTA supports the SIZE qualification,
2246 send it, adding something to the message size to allow for imprecision
2247 and things that get added en route. Exim keeps the number of lines
2248 in a message, so we can give an accurate value for the original message, but we
2249 need some additional to handle added headers. (Double "." characters don't get
2250 included in the count.) */
2251
2252 if (sx->peer_offered & PEER_OFFERED_SIZE)
2253 {
2254 sprintf(CS p, " SIZE=%d", message_size+message_linecount+sx->ob->size_addition);
2255 while (*p) p++;
2256 }
2257
2258 #ifndef DISABLE_PRDR
2259 /* If it supports Per-Recipient Data Reponses, and we have omre than one recipient,
2260 request that */
2261
2262 sx->prdr_active = FALSE;
2263 if (sx->peer_offered & PEER_OFFERED_PRDR)
2264 for (addr = addrlist; addr; addr = addr->next)
2265 if (addr->transport_return == PENDING_DEFER)
2266 {
2267 for (addr = addr->next; addr; addr = addr->next)
2268 if (addr->transport_return == PENDING_DEFER)
2269 { /* at least two recipients to send */
2270 sx->prdr_active = TRUE;
2271 sprintf(CS p, " PRDR"); p += 5;
2272 break;
2273 }
2274 break;
2275 }
2276 #endif
2277
2278 #ifdef SUPPORT_I18N
2279 /* If it supports internationalised messages, and this meesage need that,
2280 request it */
2281
2282 if ( sx->peer_offered & PEER_OFFERED_UTF8
2283 && addrlist->prop.utf8_msg
2284 && !addrlist->prop.utf8_downcvt
2285 )
2286 Ustrcpy(p, " SMTPUTF8"), p += 9;
2287 #endif
2288
2289 /* check if all addresses have DSN-lasthop flag; do not send RET and ENVID if so */
2290 for (sx->dsn_all_lasthop = TRUE, addr = addrlist, address_count = 0;
2291 addr && address_count < sx->max_rcpt;
2292 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
2293 {
2294 address_count++;
2295 if (!(addr->dsn_flags & rf_dsnlasthop))
2296 {
2297 sx->dsn_all_lasthop = FALSE;
2298 break;
2299 }
2300 }
2301
2302 /* Add any DSN flags to the mail command */
2303
2304 if (sx->peer_offered & PEER_OFFERED_DSN && !sx->dsn_all_lasthop)
2305 {
2306 if (dsn_ret == dsn_ret_hdrs)
2307 { Ustrcpy(p, " RET=HDRS"); p += 9; }
2308 else if (dsn_ret == dsn_ret_full)
2309 { Ustrcpy(p, " RET=FULL"); p += 9; }
2310
2311 if (dsn_envid)
2312 {
2313 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ENVID=%s", dsn_envid);
2314 while (*p) p++;
2315 }
2316 }
2317
2318 /* If an authenticated_sender override has been specified for this transport
2319 instance, expand it. If the expansion is forced to fail, and there was already
2320 an authenticated_sender for this message, the original value will be used.
2321 Other expansion failures are serious. An empty result is ignored, but there is
2322 otherwise no check - this feature is expected to be used with LMTP and other
2323 cases where non-standard addresses (e.g. without domains) might be required. */
2324
2325 if (smtp_mail_auth_str(p, sizeof(sx->buffer) - (p-sx->buffer), addrlist, sx->ob))
2326 return ERROR;
2327
2328 return OK;
2329 }
2330
2331
2332 static void
2333 build_rcptcmd_options(smtp_context * sx, const address_item * addr)
2334 {
2335 uschar * p = sx->buffer;
2336 *p = 0;
2337
2338 /* Add any DSN flags to the rcpt command */
2339
2340 if (sx->peer_offered & PEER_OFFERED_DSN && !(addr->dsn_flags & rf_dsnlasthop))
2341 {
2342 if (addr->dsn_flags & rf_dsnflags)
2343 {
2344 int i;
2345 BOOL first = TRUE;
2346
2347 Ustrcpy(p, " NOTIFY=");
2348 while (*p) p++;
2349 for (i = 0; i < nelem(rf_list); i++) if (addr->dsn_flags & rf_list[i])
2350 {
2351 if (!first) *p++ = ',';
2352 first = FALSE;
2353 Ustrcpy(p, rf_names[i]);
2354 while (*p) p++;
2355 }
2356 }
2357
2358 if (addr->dsn_orcpt)
2359 {
2360 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ORCPT=%s",
2361 addr->dsn_orcpt);
2362 while (*p) p++;
2363 }
2364 }
2365 }
2366
2367
2368
2369 /*
2370 Return:
2371 0 good, rcpt results in addr->transport_return (PENDING_OK, DEFER, FAIL)
2372 -1 MAIL response error
2373 -2 any non-MAIL read i/o error
2374 -3 non-MAIL response timeout
2375 -4 internal error; channel still usable
2376 -5 transmit failed
2377 */
2378
2379 int
2380 smtp_write_mail_and_rcpt_cmds(smtp_context * sx, int * yield)
2381 {
2382 address_item * addr;
2383 int address_count;
2384 int rc;
2385
2386 if (build_mailcmd_options(sx, sx->first_addr) != OK)
2387 {
2388 *yield = ERROR;
2389 return -4;
2390 }
2391
2392 /* From here until we send the DATA command, we can make use of PIPELINING
2393 if the server host supports it. The code has to be able to check the responses
2394 at any point, for when the buffer fills up, so we write it totally generally.
2395 When PIPELINING is off, each command written reports that it has flushed the
2396 buffer. */
2397
2398 sx->pending_MAIL = TRUE; /* The block starts with MAIL */
2399
2400 {
2401 uschar * s = sx->from_addr;
2402 #ifdef SUPPORT_I18N
2403 uschar * errstr = NULL;
2404
2405 /* If we must downconvert, do the from-address here. Remember we had to
2406 for the to-addresses (done below), and also (ugly) for re-doing when building
2407 the delivery log line. */
2408
2409 if ( sx->addrlist->prop.utf8_msg
2410 && (sx->addrlist->prop.utf8_downcvt || !(sx->peer_offered & PEER_OFFERED_UTF8))
2411 )
2412 {
2413 if (s = string_address_utf8_to_alabel(s, &errstr), errstr)
2414 {
2415 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE);
2416 *yield = ERROR;
2417 return -4;
2418 }
2419 setflag(sx->addrlist, af_utf8_downcvt);
2420 }
2421 #endif
2422
2423 rc = smtp_write_command(&sx->outblock, pipelining_active,
2424 "MAIL FROM:<%s>%s\r\n", s, sx->buffer);
2425 }
2426
2427 mail_command = string_copy(big_buffer); /* Save for later error message */
2428
2429 switch(rc)
2430 {
2431 case -1: /* Transmission error */
2432 return -5;
2433
2434 case +1: /* Cmd was sent */
2435 if (!smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer), '2',
2436 sx->ob->command_timeout))
2437 {
2438 if (errno == 0 && sx->buffer[0] == '4')
2439 {
2440 errno = ERRNO_MAIL4XX;
2441 sx->addrlist->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
2442 }
2443 return -1;
2444 }
2445 sx->pending_MAIL = FALSE;
2446 break;
2447
2448 /* otherwise zero: command queued for pipeline */
2449 }
2450
2451 /* Pass over all the relevant recipient addresses for this host, which are the
2452 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
2453 several before we have to read the responses for those seen so far. This
2454 checking is done by a subroutine because it also needs to be done at the end.
2455 Send only up to max_rcpt addresses at a time, leaving next_addr pointing to
2456 the next one if not all are sent.
2457
2458 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
2459 last address because we want to abort if any recipients have any kind of
2460 problem, temporary or permanent. We know that all recipient addresses will have
2461 the PENDING_DEFER status, because only one attempt is ever made, and we know
2462 that max_rcpt will be large, so all addresses will be done at once.
2463
2464 For verify we flush the pipeline after any (the only) rcpt address. */
2465
2466 for (addr = sx->first_addr, address_count = 0;
2467 addr && address_count < sx->max_rcpt;
2468 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
2469 {
2470 int count;
2471 BOOL no_flush;
2472 uschar * rcpt_addr;
2473
2474 addr->dsn_aware = sx->peer_offered & PEER_OFFERED_DSN
2475 ? dsn_support_yes : dsn_support_no;
2476
2477 address_count++;
2478 no_flush = pipelining_active && !sx->verify && (!mua_wrapper || addr->next);
2479
2480 build_rcptcmd_options(sx, addr);
2481
2482 /* Now send the RCPT command, and process outstanding responses when
2483 necessary. After a timeout on RCPT, we just end the function, leaving the
2484 yield as OK, because this error can often mean that there is a problem with
2485 just one address, so we don't want to delay the host. */
2486
2487 rcpt_addr = transport_rcpt_address(addr, sx->tblock->rcpt_include_affixes);
2488
2489 #ifdef SUPPORT_I18N
2490 if ( testflag(sx->addrlist, af_utf8_downcvt)
2491 && !(rcpt_addr = string_address_utf8_to_alabel(rcpt_addr, NULL))
2492 )
2493 {
2494 /*XXX could we use a per-address errstr here? Not fail the whole send? */
2495 errno = ERRNO_EXPANDFAIL;
2496 return -5; /*XXX too harsh? */
2497 }
2498 #endif
2499
2500 count = smtp_write_command(&sx->outblock, no_flush, "RCPT TO:<%s>%s%s\r\n",
2501 rcpt_addr, sx->igquotstr, sx->buffer);
2502
2503 if (count < 0) return -5;
2504 if (count > 0)
2505 {
2506 switch(sync_responses(sx, count, 0))
2507 {
2508 case 3: sx->ok = TRUE; /* 2xx & 5xx => OK & progress made */
2509 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
2510 break;
2511
2512 case 1: sx->ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2513 if (!sx->lmtp) /* can't tell about progress yet */
2514 sx->completed_addr = TRUE;
2515 case 0: /* No 2xx or 5xx, but no probs */
2516 break;
2517
2518 case -1: return -3; /* Timeout on RCPT */
2519 case -2: return -2; /* non-MAIL read i/o error */
2520 default: return -1; /* any MAIL error */
2521 }
2522 sx->pending_MAIL = FALSE; /* Dealt with MAIL */
2523 }
2524 } /* Loop for next address */
2525
2526 sx->next_addr = addr;
2527 return 0;
2528 }
2529
2530
2531 #ifdef SUPPORT_TLS
2532 /*****************************************************
2533 * Proxy TLS connection for another transport process *
2534 ******************************************************/
2535 /*
2536 Use the given buffer as a staging area, and select on both the given fd
2537 and the TLS'd client-fd for data to read (per the coding in ip_recv() and
2538 fd_ready() this is legitimate). Do blocking full-size writes, and reads
2539 under a timeout.
2540
2541 Arguments:
2542 buf space to use for buffering
2543 bufsiz size of buffer
2544 proxy_fd comms to proxied process
2545 timeout per-read timeout, seconds
2546 */
2547
2548 void
2549 smtp_proxy_tls(uschar * buf, size_t bsize, int proxy_fd, int timeout)
2550 {
2551 fd_set fds;
2552 int max_fd = MAX(proxy_fd, tls_out.active) + 1;
2553 int rc, i, fd_bits, nbytes;
2554
2555 set_process_info("proxying TLS connection for continued transport");
2556 FD_ZERO(&fds);
2557 FD_SET(tls_out.active, &fds);
2558 FD_SET(proxy_fd, &fds);
2559
2560 for (fd_bits = 3; fd_bits; )
2561 {
2562 time_t time_left = timeout;
2563 time_t time_start = time(NULL);
2564
2565 /* wait for data */
2566 do
2567 {
2568 struct timeval tv = { time_left, 0 };
2569
2570 rc = select(max_fd, (SELECT_ARG2_TYPE *)&fds, NULL, NULL, &tv);
2571
2572 if (rc < 0 && errno == EINTR)
2573 if ((time_left -= time(NULL) - time_start) > 0) continue;
2574
2575 if (rc <= 0)
2576 {
2577 DEBUG(D_transport) if (rc == 0) debug_printf("%s: timed out\n", __FUNCTION__);
2578 return;
2579 }
2580 }
2581 while (rc < 0 || !(FD_ISSET(tls_out.active, &fds) || FD_ISSET(proxy_fd, &fds)));
2582
2583 /* handle inbound data */
2584 if (FD_ISSET(tls_out.active, &fds))
2585 if ((rc = tls_read(FALSE, buf, bsize)) <= 0)
2586 {
2587 fd_bits &= ~1;
2588 FD_CLR(tls_out.active, &fds);
2589 shutdown(proxy_fd, SHUT_WR);
2590 }
2591 else
2592 {
2593 for (nbytes = 0; rc - nbytes > 0; nbytes += i)
2594 if ((i = write(proxy_fd, buf + nbytes, rc - nbytes)) < 0) return;
2595 }
2596 else if (fd_bits & 1)
2597 FD_SET(tls_out.active, &fds);
2598
2599 /* handle outbound data */
2600 if (FD_ISSET(proxy_fd, &fds))
2601 if ((rc = read(proxy_fd, buf, bsize)) <= 0)
2602 {
2603 fd_bits &= ~2;
2604 FD_CLR(proxy_fd, &fds);
2605 shutdown(tls_out.active, SHUT_WR);
2606 }
2607 else
2608 {
2609 for (nbytes = 0; rc - nbytes > 0; nbytes += i)
2610 if ((i = tls_write(FALSE, buf + nbytes, rc - nbytes)) < 0) return;
2611 }
2612 else if (fd_bits & 2)
2613 FD_SET(proxy_fd, &fds);
2614 }
2615 }
2616 #endif
2617
2618
2619 /*************************************************
2620 * Deliver address list to given host *
2621 *************************************************/
2622
2623 /* If continue_hostname is not null, we get here only when continuing to
2624 deliver down an existing channel. The channel was passed as the standard
2625 input. TLS is never active on a passed channel; the previous process always
2626 closes it down before passing the connection on.
2627
2628 Otherwise, we have to make a connection to the remote host, and do the
2629 initial protocol exchange.
2630
2631 When running as an MUA wrapper, if the sender or any recipient is rejected,
2632 temporarily or permanently, we force failure for all recipients.
2633
2634 Arguments:
2635 addrlist chain of potential addresses to deliver; only those whose
2636 transport_return field is set to PENDING_DEFER are currently
2637 being processed; others should be skipped - they have either
2638 been delivered to an earlier host or IP address, or been
2639 failed by one of them.
2640 host host to deliver to
2641 host_af AF_INET or AF_INET6
2642 port default TCP/IP port to use, in host byte order
2643 interface interface to bind to, or NULL
2644 tblock transport instance block
2645 message_defer set TRUE if yield is OK, but all addresses were deferred
2646 because of a non-recipient, non-host failure, that is, a
2647 4xx response to MAIL FROM, DATA, or ".". This is a defer
2648 that is specific to the message.
2649 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
2650 a second attempt after TLS initialization fails
2651
2652 Returns: OK - the connection was made and the delivery attempted;
2653 the result for each address is in its data block.
2654 DEFER - the connection could not be made, or something failed
2655 while setting up the SMTP session, or there was a
2656 non-message-specific error, such as a timeout.
2657 ERROR - a filter command is specified for this transport,
2658 and there was a problem setting it up; OR helo_data
2659 or add_headers or authenticated_sender is specified
2660 for this transport, and the string failed to expand
2661 */
2662
2663 static int
2664 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
2665 uschar *interface, transport_instance *tblock,
2666 BOOL *message_defer, BOOL suppress_tls)
2667 {
2668 address_item *addr;
2669 int yield = OK;
2670 int save_errno;
2671 int rc;
2672 time_t start_delivery_time = time(NULL);
2673
2674 BOOL pass_message = FALSE;
2675 uschar *message = NULL;
2676 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
2677 uschar *p;
2678
2679 smtp_context sx;
2680
2681 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
2682 *message_defer = FALSE;
2683
2684 sx.addrlist = addrlist;
2685 sx.host = host;
2686 sx.host_af = host_af,
2687 sx.port = port;
2688 sx.interface = interface;
2689 sx.helo_data = NULL;
2690 sx.tblock = tblock;
2691 sx.verify = FALSE;
2692
2693 /* Get the channel set up ready for a message (MAIL FROM being the next
2694 SMTP command to send */
2695
2696 if ((rc = smtp_setup_conn(&sx, suppress_tls)) != OK)
2697 return rc;
2698
2699 /* If there is a filter command specified for this transport, we can now
2700 set it up. This cannot be done until the identify of the host is known. */
2701
2702 if (tblock->filter_command)
2703 {
2704 transport_filter_timeout = tblock->filter_timeout;
2705
2706 /* On failure, copy the error to all addresses, abandon the SMTP call, and
2707 yield ERROR. */
2708
2709 if (!transport_set_up_command(&transport_filter_argv,
2710 tblock->filter_command, TRUE, DEFER, addrlist,
2711 string_sprintf("%.50s transport", tblock->name), NULL))
2712 {
2713 set_errno_nohost(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
2714 FALSE);
2715 yield = ERROR;
2716 goto SEND_QUIT;
2717 }
2718
2719 if ( transport_filter_argv
2720 && *transport_filter_argv
2721 && **transport_filter_argv
2722 && sx.peer_offered & PEER_OFFERED_CHUNKING
2723 )
2724 {
2725 sx.peer_offered &= ~PEER_OFFERED_CHUNKING;
2726 DEBUG(D_transport) debug_printf("CHUNKING not usable due to transport filter\n");
2727 }
2728 }
2729
2730 sx.first_addr = addrlist;
2731
2732 /* For messages that have more than the maximum number of envelope recipients,
2733 we want to send several transactions down the same SMTP connection. (See
2734 comments in deliver.c as to how this reconciles, heuristically, with
2735 remote_max_parallel.) This optimization was added to Exim after the following
2736 code was already working. The simplest way to put it in without disturbing the
2737 code was to use a goto to jump back to this point when there is another
2738 transaction to handle. */
2739
2740 SEND_MESSAGE:
2741 sx.from_addr = return_path;
2742 sx.sync_addr = sx.first_addr;
2743 sx.ok = FALSE;
2744 sx.send_rset = TRUE;
2745 sx.completed_addr = FALSE;
2746
2747
2748 /* If we are a continued-connection-after-verify the MAIL and RCPT
2749 commands were already sent; do not re-send but do mark the addrs as
2750 having been accepted up to RCPT stage. A traditional cont-conn
2751 always has a sequence number greater than one. */
2752
2753 if (continue_hostname && continue_sequence == 1)
2754 {
2755 address_item * addr;
2756
2757 sx.peer_offered = smtp_peer_options;
2758 sx.pending_MAIL = FALSE;
2759 sx.ok = TRUE;
2760 sx.next_addr = NULL;
2761
2762 for (addr = addrlist; addr; addr = addr->next)
2763 addr->transport_return = PENDING_OK;
2764 }
2765 else
2766 {
2767 /* Initiate a message transfer. */
2768
2769 switch(smtp_write_mail_and_rcpt_cmds(&sx, &yield))
2770 {
2771 case 0: break;
2772 case -1: case -2: goto RESPONSE_FAILED;
2773 case -3: goto END_OFF;
2774 case -4: goto SEND_QUIT;
2775 default: goto SEND_FAILED;
2776 }
2777
2778 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
2779 permanently or temporarily. We should have flushed and synced after the last
2780 RCPT. */
2781
2782 if (mua_wrapper)
2783 {
2784 address_item *badaddr;
2785 for (badaddr = sx.first_addr; badaddr; badaddr = badaddr->next)
2786 if (badaddr->transport_return != PENDING_OK)
2787 {
2788 /*XXX could we find a better errno than 0 here? */
2789 set_errno_nohost(addrlist, 0, badaddr->message, FAIL,
2790 testflag(badaddr, af_pass_message));
2791 sx.ok = FALSE;
2792 break;
2793 }
2794 }
2795 }
2796
2797 /* If ok is TRUE, we know we have got at least one good recipient, and must now
2798 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
2799 have a good recipient buffered up if we are pipelining. We don't want to waste
2800 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
2801 are pipelining. The responses are all handled by sync_responses().
2802 If using CHUNKING, do not send a BDAT until we know how big a chunk we want
2803 to send is. */
2804
2805 if ( !(sx.peer_offered & PEER_OFFERED_CHUNKING)
2806 && (sx.ok || (pipelining_active && !mua_wrapper)))
2807 {
2808 int count = smtp_write_command(&sx.outblock, FALSE, "DATA\r\n");
2809
2810 if (count < 0) goto SEND_FAILED;
2811 switch(sync_responses(&sx, count, sx.ok ? +1 : -1))
2812 {
2813 case 3: sx.ok = TRUE; /* 2xx & 5xx => OK & progress made */
2814 case 2: sx.completed_addr = TRUE; /* 5xx (only) => progress made */
2815 break;
2816
2817 case 1: sx.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2818 if (!sx.lmtp) sx.completed_addr = TRUE; /* can't tell about progress yet */
2819 case 0: break; /* No 2xx or 5xx, but no probs */
2820
2821 case -1: goto END_OFF; /* Timeout on RCPT */
2822 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2823 }
2824 pipelining_active = FALSE;
2825 data_command = string_copy(big_buffer); /* Save for later error message */
2826 }
2827
2828 /* If there were no good recipients (but otherwise there have been no
2829 problems), just set ok TRUE, since we have handled address-specific errors
2830 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
2831 for handling the SMTP dot-handling protocol, flagging to apply to headers as
2832 well as body. Set the appropriate timeout value to be used for each chunk.
2833 (Haven't been able to make it work using select() for writing yet.) */
2834
2835 if (!(sx.peer_offered & PEER_OFFERED_CHUNKING) && !sx.ok)
2836 {
2837 /* Save the first address of the next batch. */
2838 sx.first_addr = sx.next_addr;
2839
2840 sx.ok = TRUE;
2841 }
2842 else
2843 {
2844 transport_ctx tctx = {
2845 tblock,
2846 addrlist,
2847 US".", US"..", /* Escaping strings */
2848 topt_use_crlf | topt_escape_headers
2849 | (tblock->body_only ? topt_no_headers : 0)
2850 | (tblock->headers_only ? topt_no_body : 0)
2851 | (tblock->return_path_add ? topt_add_return_path : 0)
2852 | (tblock->delivery_date_add ? topt_add_delivery_date : 0)
2853 | (tblock->envelope_to_add ? topt_add_envelope_to : 0)
2854 };
2855
2856 /* If using CHUNKING we need a callback from the generic transport
2857 support to us, for the sending of BDAT smtp commands and the reaping
2858 of responses. The callback needs a whole bunch of state so set up
2859 a transport-context structure to be passed around. */
2860
2861 if (sx.peer_offered & PEER_OFFERED_CHUNKING)
2862 {
2863 tctx.check_string = tctx.escape_string = NULL;
2864 tctx.options |= topt_use_bdat;
2865 tctx.chunk_cb = smtp_chunk_cmd_callback;
2866 sx.pending_BDAT = FALSE;
2867 sx.good_RCPT = sx.ok;
2868 sx.cmd_count = 0;
2869 tctx.smtp_context = &sx;
2870 }
2871 else
2872 tctx.options |= topt_end_dot;
2873
2874 /* Save the first address of the next batch. */
2875 sx.first_addr = sx.next_addr;
2876
2877 /* Responses from CHUNKING commands go in buffer. Otherwise,
2878 there has not been a response. */
2879
2880 sx.buffer[0] = 0;
2881
2882 sigalrm_seen = FALSE;
2883 transport_write_timeout = sx.ob->data_timeout;
2884 smtp_command = US"sending data block"; /* For error messages */
2885 DEBUG(D_transport|D_v)
2886 if (sx.peer_offered & PEER_OFFERED_CHUNKING)
2887 debug_printf(" will write message using CHUNKING\n");
2888 else
2889 debug_printf(" SMTP>> writing message and terminating \".\"\n");
2890 transport_count = 0;
2891
2892 #ifndef DISABLE_DKIM
2893 sx.ok = dkim_transport_write_message(sx.inblock.sock, &tctx, &sx.ob->dkim,
2894 CUSS &message);
2895 #else
2896 sx.ok = transport_write_message(sx.inblock.sock, &tctx, 0);
2897 #endif
2898
2899 /* transport_write_message() uses write() because it is called from other
2900 places to write to non-sockets. This means that under some OS (e.g. Solaris)
2901 it can exit with "Broken pipe" as its error. This really means that the
2902 socket got closed at the far end. */
2903
2904 transport_write_timeout = 0; /* for subsequent transports */
2905
2906 /* Failure can either be some kind of I/O disaster (including timeout),
2907 or the failure of a transport filter or the expansion of added headers.
2908 Or, when CHUNKING, it can be a protocol-detected failure. */
2909
2910 if (!sx.ok)
2911 if (message) goto SEND_FAILED;
2912 else goto RESPONSE_FAILED;
2913
2914 /* We used to send the terminating "." explicitly here, but because of
2915 buffering effects at both ends of TCP/IP connections, you don't gain
2916 anything by keeping it separate, so it might as well go in the final
2917 data buffer for efficiency. This is now done by setting the topt_end_dot
2918 flag above. */
2919
2920 smtp_command = US"end of data";
2921
2922 if (sx.peer_offered & PEER_OFFERED_CHUNKING && sx.cmd_count > 1)
2923 {
2924 /* Reap any outstanding MAIL & RCPT commands, but not a DATA-go-ahead */
2925 switch(sync_responses(&sx, sx.cmd_count-1, 0))
2926 {
2927 case 3: sx.ok = TRUE; /* 2xx & 5xx => OK & progress made */
2928 case 2: sx.completed_addr = TRUE; /* 5xx (only) => progress made */
2929 break;
2930
2931 case 1: sx.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2932 if (!sx.lmtp) sx.completed_addr = TRUE; /* can't tell about progress yet */
2933 case 0: break; /* No 2xx or 5xx, but no probs */
2934
2935 case -1: goto END_OFF; /* Timeout on RCPT */
2936 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2937 }
2938 }
2939
2940 #ifndef DISABLE_PRDR
2941 /* For PRDR we optionally get a partial-responses warning
2942 * followed by the individual responses, before going on with
2943 * the overall response. If we don't get the warning then deal
2944 * with per non-PRDR. */
2945 if(sx.prdr_active)
2946 {
2947 sx.ok = smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer), '3',
2948 sx.ob->final_timeout);
2949 if (!sx.ok && errno == 0) switch(sx.buffer[0])
2950 {
2951 case '2': sx.prdr_active = FALSE;
2952 sx.ok = TRUE;
2953 break;
2954 case '4': errno = ERRNO_DATA4XX;
2955 addrlist->more_errno |=
2956 ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
2957 break;
2958 }
2959 }
2960 else
2961 #endif
2962
2963 /* For non-PRDR SMTP, we now read a single response that applies to the
2964 whole message. If it is OK, then all the addresses have been delivered. */
2965
2966 if (!sx.lmtp)
2967 {
2968 sx.ok = smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer), '2',
2969 sx.ob->final_timeout);
2970 if (!sx.ok && errno == 0 && sx.buffer[0] == '4')
2971 {
2972 errno = ERRNO_DATA4XX;
2973 addrlist->more_errno |= ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
2974 }
2975 }
2976
2977 /* For LMTP, we get back a response for every RCPT command that we sent;
2978 some may be accepted and some rejected. For those that get a response, their
2979 status is fixed; any that are accepted have been handed over, even if later
2980 responses crash - at least, that's how I read RFC 2033.
2981
2982 If all went well, mark the recipient addresses as completed, record which
2983 host/IPaddress they were delivered to, and cut out RSET when sending another
2984 message down the same channel. Write the completed addresses to the journal
2985 now so that they are recorded in case there is a crash of hardware or
2986 software before the spool gets updated. Also record the final SMTP
2987 confirmation if needed (for SMTP only). */
2988
2989 if (sx.ok)
2990 {
2991 int flag = '=';
2992 int delivery_time = (int)(time(NULL) - start_delivery_time);
2993 int len;
2994 uschar *conf = NULL;
2995
2996 sx.send_rset = FALSE;
2997 pipelining_active = FALSE;
2998
2999 /* Set up confirmation if needed - applies only to SMTP */
3000
3001 if (
3002 #ifdef DISABLE_EVENT
3003 LOGGING(smtp_confirmation) &&
3004 #endif
3005 !sx.lmtp
3006 )
3007 {
3008 const uschar *s = string_printing(sx.buffer);
3009 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
3010 conf = (s == sx.buffer)? (uschar *)string_copy(s) : US s;
3011 }
3012
3013 /* Process all transported addresses - for LMTP or PRDR, read a status for
3014 each one. */
3015
3016 for (addr = addrlist; addr != sx.first_addr; addr = addr->next)
3017 {
3018 if (addr->transport_return != PENDING_OK) continue;
3019
3020 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
3021 remaining addresses. Otherwise, it's a return code for just the one
3022 address. For temporary errors, add a retry item for the address so that
3023 it doesn't get tried again too soon. */
3024
3025 #ifndef DISABLE_PRDR
3026 if (sx.lmtp || sx.prdr_active)
3027 #else
3028 if (sx.lmtp)
3029 #endif
3030 {
3031 if (!smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer), '2',
3032 sx.ob->final_timeout))
3033 {
3034 if (errno != 0 || sx.buffer[0] == 0) goto RESPONSE_FAILED;
3035 addr->message = string_sprintf(
3036 #ifndef DISABLE_PRDR
3037 "%s error after %s: %s", sx.prdr_active ? "PRDR":"LMTP",
3038 #else
3039 "LMTP error after %s: %s",
3040 #endif
3041 data_command, string_printing(sx.buffer));
3042 setflag(addr, af_pass_message); /* Allow message to go to user */
3043 if (sx.buffer[0] == '5')
3044 addr->transport_return = FAIL;
3045 else
3046 {
3047 errno = ERRNO_DATA4XX;
3048 addr->more_errno |= ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
3049 addr->transport_return = DEFER;
3050 #ifndef DISABLE_PRDR
3051 if (!sx.prdr_active)
3052 #endif
3053 retry_add_item(addr, addr->address_retry_key, 0);
3054 }
3055 continue;
3056 }
3057 sx.completed_addr = TRUE; /* NOW we can set this flag */
3058 if (LOGGING(smtp_confirmation))
3059 {
3060 const uschar *s = string_printing(sx.buffer);
3061 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
3062 conf = (s == sx.buffer) ? US string_copy(s) : US s;
3063 }
3064 }
3065
3066 /* SMTP, or success return from LMTP for this address. Pass back the
3067 actual host that was used. */
3068
3069 addr->transport_return = OK;
3070 addr->more_errno = delivery_time;
3071 addr->host_used = host;
3072 addr->special_action = flag;
3073 addr->message = conf;
3074 #ifndef DISABLE_PRDR
3075 if (sx.prdr_active) addr->flags |= af_prdr_used;
3076 #endif
3077 if (sx.peer_offered & PEER_OFFERED_CHUNKING) addr->flags |= af_chunking_used;
3078 flag = '-';
3079
3080 #ifndef DISABLE_PRDR
3081 if (!sx.prdr_active)
3082 #endif
3083 {
3084 /* Update the journal. For homonymic addresses, use the base address plus
3085 the transport name. See lots of comments in deliver.c about the reasons
3086 for the complications when homonyms are involved. Just carry on after
3087 write error, as it may prove possible to update the spool file later. */
3088
3089 if (testflag(addr, af_homonym))
3090 sprintf(CS sx.buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
3091 else
3092 sprintf(CS sx.buffer, "%.500s\n", addr->unique);
3093
3094 DEBUG(D_deliver) debug_printf("S:journalling %s\n", sx.buffer);
3095 len = Ustrlen(CS sx.buffer);
3096 if (write(journal_fd, sx.buffer, len) != len)
3097 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
3098 "%s: %s", sx.buffer, strerror(errno));
3099 }
3100 }
3101
3102 #ifndef DISABLE_PRDR
3103 if (sx.prdr_active)
3104 {
3105 /* PRDR - get the final, overall response. For any non-success
3106 upgrade all the address statuses. */
3107 sx.ok = smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer), '2',
3108 sx.ob->final_timeout);
3109 if (!sx.ok)
3110 {
3111 if(errno == 0 && sx.buffer[0] == '4')
3112 {
3113 errno = ERRNO_DATA4XX;
3114 addrlist->more_errno |= ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
3115 }
3116 for (addr = addrlist; addr != sx.first_addr; addr = addr->next)
3117 if (sx.buffer[0] == '5' || addr->transport_return == OK)
3118 addr->transport_return = PENDING_OK; /* allow set_errno action */
3119 goto RESPONSE_FAILED;
3120 }
3121
3122 /* Update the journal, or setup retry. */
3123 for (addr = addrlist; addr != sx.first_addr; addr = addr->next)
3124 if (addr->transport_return == OK)
3125 {
3126 if (testflag(addr, af_homonym))
3127 sprintf(CS sx.buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
3128 else
3129 sprintf(CS sx.buffer, "%.500s\n", addr->unique);
3130
3131 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s\n", sx.buffer);
3132 len = Ustrlen(CS sx.buffer);
3133 if (write(journal_fd, sx.buffer, len) != len)
3134 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
3135 "%s: %s", sx.buffer, strerror(errno));
3136 }
3137 else if (addr->transport_return == DEFER)
3138 retry_add_item(addr, addr->address_retry_key, -2);
3139 }
3140 #endif
3141
3142 /* Ensure the journal file is pushed out to disk. */
3143
3144 if (EXIMfsync(journal_fd) < 0)
3145 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
3146 strerror(errno));
3147 }
3148 }
3149
3150
3151 /* Handle general (not specific to one address) failures here. The value of ok
3152 is used to skip over this code on the falling through case. A timeout causes a
3153 deferral. Other errors may defer or fail according to the response code, and
3154 may set up a special errno value, e.g. after connection chopped, which is
3155 assumed if errno == 0 and there is no text in the buffer. If control reaches
3156 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
3157 the problem is not related to this specific message. */
3158
3159 if (!sx.ok)
3160 {
3161 int code, set_rc;
3162 uschar * set_message;
3163
3164 RESPONSE_FAILED:
3165 {
3166 save_errno = errno;
3167 message = NULL;
3168 sx.send_quit = check_response(host, &save_errno, addrlist->more_errno,
3169 sx.buffer, &code, &message, &pass_message);
3170 goto FAILED;
3171 }
3172
3173 SEND_FAILED:
3174 {
3175 save_errno = errno;
3176 code = '4';
3177 message = string_sprintf("send() to %s [%s] failed: %s",
3178 host->name, host->address, message ? message : US strerror(save_errno));
3179 sx.send_quit = FALSE;
3180 goto FAILED;
3181 }
3182
3183 FAILED:
3184 {
3185 BOOL message_error;
3186
3187 sx.ok = FALSE; /* For when reached by GOTO */
3188 set_message = message;
3189
3190 /* We want to handle timeouts after MAIL or "." and loss of connection after
3191 "." specially. They can indicate a problem with the sender address or with
3192 the contents of the message rather than a real error on the connection. These
3193 cases are treated in the same way as a 4xx response. This next bit of code
3194 does the classification. */
3195
3196 switch(save_errno)
3197 {
3198 case 0:
3199 case ERRNO_MAIL4XX:
3200 case ERRNO_DATA4XX:
3201 message_error = TRUE;
3202 break;
3203
3204 case ETIMEDOUT:
3205 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
3206 Ustrncmp(smtp_command,"end ",4) == 0;
3207 break;
3208
3209 case ERRNO_SMTPCLOSED:
3210 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
3211 break;
3212
3213 default:
3214 message_error = FALSE;
3215 break;
3216 }
3217
3218 /* Handle the cases that are treated as message errors. These are:
3219
3220 (a) negative response or timeout after MAIL
3221 (b) negative response after DATA
3222 (c) negative response or timeout or dropped connection after "."
3223 (d) utf8 support required and not offered
3224
3225 It won't be a negative response or timeout after RCPT, as that is dealt
3226 with separately above. The action in all cases is to set an appropriate
3227 error code for all the addresses, but to leave yield set to OK because the
3228 host itself has not failed. Of course, it might in practice have failed
3229 when we've had a timeout, but if so, we'll discover that at the next
3230 delivery attempt. For a temporary error, set the message_defer flag, and
3231 write to the logs for information if this is not the last host. The error
3232 for the last host will be logged as part of the address's log line. */
3233
3234 if (message_error)
3235 {
3236 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
3237
3238 /* If there's an errno, the message contains just the identity of
3239 the host. */
3240
3241 if (code == '5')
3242 set_rc = FAIL;
3243 else /* Anything other than 5 is treated as temporary */
3244 {
3245 set_rc = DEFER;
3246 if (save_errno > 0)
3247 message = US string_sprintf("%s: %s", message, strerror(save_errno));
3248 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
3249 msglog_line(host, message);
3250 *message_defer = TRUE;
3251 }
3252 }
3253
3254 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
3255 ".", or some other transportation error. We defer all addresses and yield
3256 DEFER, except for the case of failed add_headers expansion, or a transport
3257 filter failure, when the yield should be ERROR, to stop it trying other
3258 hosts. */
3259
3260 else
3261 {
3262 set_rc = DEFER;
3263 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
3264 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
3265 }
3266 }
3267
3268 set_errno(addrlist, save_errno, set_message, set_rc, pass_message, host
3269 #ifdef EXPERIMENTAL_DSN_INFO
3270 , sx.smtp_greeting, sx.helo_response
3271 #endif
3272 );
3273 }
3274
3275
3276 /* If all has gone well, send_quit will be set TRUE, implying we can end the
3277 SMTP session tidily. However, if there were too many addresses to send in one
3278 message (indicated by first_addr being non-NULL) we want to carry on with the
3279 rest of them. Also, it is desirable to send more than one message down the SMTP
3280 connection if there are several waiting, provided we haven't already sent so
3281 many as to hit the configured limit. The function transport_check_waiting looks
3282 for a waiting message and returns its id. Then transport_pass_socket tries to
3283 set up a continued delivery by passing the socket on to another process. The
3284 variable send_rset is FALSE if a message has just been successfully transfered.
3285
3286 If we are already sending down a continued channel, there may be further
3287 addresses not yet delivered that are aimed at the same host, but which have not
3288 been passed in this run of the transport. In this case, continue_more will be
3289 true, and all we should do is send RSET if necessary, and return, leaving the
3290 channel open.
3291
3292 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
3293 do not want to continue with other messages down the same channel, because that
3294 can lead to looping between two or more messages, all with the same,
3295 temporarily failing address(es). [The retry information isn't updated yet, so
3296 new processes keep on trying.] We probably also don't want to try more of this
3297 message's addresses either.
3298
3299 If we have started a TLS session, we have to end it before passing the
3300 connection to a new process. However, not all servers can handle this (Exim
3301 can), so we do not pass such a connection on if the host matches
3302 hosts_nopass_tls. */
3303
3304 DEBUG(D_transport)
3305 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
3306 "yield=%d first_address is %sNULL\n", sx.ok, sx.send_quit,
3307 sx.send_rset, continue_more, yield, sx.first_addr ? "not " : "");
3308
3309 if (sx.completed_addr && sx.ok && sx.send_quit)
3310 {
3311 BOOL more;
3312 smtp_compare_t t_compare;
3313
3314 t_compare.tblock = tblock;
3315 t_compare.current_sender_address = sender_address;
3316
3317 if ( sx.first_addr != NULL
3318 || continue_more
3319 || (
3320 #ifdef SUPPORT_TLS
3321 ( tls_out.active < 0 && !continue_proxy_cipher
3322 || verify_check_given_host(&sx.ob->hosts_nopass_tls, host) != OK
3323 )
3324 &&
3325 #endif
3326 transport_check_waiting(tblock->name, host->name,
3327 tblock->connection_max_messages, new_message_id, &more,
3328 (oicf)smtp_are_same_identities, (void*)&t_compare)
3329 ) )
3330 {
3331 uschar *msg;
3332 BOOL pass_message;
3333
3334 if (sx.send_rset)
3335 if (! (sx.ok = smtp_write_command(&sx.outblock, FALSE, "RSET\r\n") >= 0))
3336 {
3337 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
3338 host->address, strerror(errno));
3339 sx.send_quit = FALSE;
3340 }
3341 else if (! (sx.ok = smtp_read_response(&sx.inblock, sx.buffer,
3342 sizeof(sx.buffer), '2', sx.ob->command_timeout)))
3343 {
3344 int code;
3345 sx.send_quit = check_response(host, &errno, 0, sx.buffer, &code, &msg,
3346 &pass_message);
3347 if (!sx.send_quit)
3348 {
3349 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
3350 host->name, host->address, msg);
3351 }
3352 }
3353
3354 /* Either RSET was not needed, or it succeeded */
3355
3356 if (sx.ok)
3357 {
3358 int pfd[2];
3359 int socket_fd = sx.inblock.sock;
3360
3361
3362 if (sx.first_addr != NULL) /* More addresses still to be sent */
3363 { /* in this run of the transport */
3364 continue_sequence++; /* Causes * in logging */
3365 goto SEND_MESSAGE;
3366 }
3367 if (continue_more) return yield; /* More addresses for another run */
3368
3369 /* Pass the connection on to a new Exim process. */
3370 #ifdef SUPPORT_TLS
3371 if (tls_out.active >= 0)
3372 if (verify_check_given_host(&sx.ob->hosts_noproxy_tls, host) == OK)
3373 {
3374 /* Pass the socket, for direct use, to a new Exim process. Before
3375 doing so, we must shut down TLS. Not all MTAs allow for the
3376 continuation of the SMTP session when TLS is shut down. We test for
3377 this by sending a new EHLO. If we don't get a good response, we don't
3378 attempt to pass the socket on. */
3379
3380 tls_close(FALSE, TRUE);
3381 smtp_peer_options = smtp_peer_options_wrap;
3382 sx.ok = !sx.smtps
3383 && smtp_write_command(&sx.outblock, FALSE,
3384 "EHLO %s\r\n", sx.helo_data) >= 0
3385 && smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer),
3386 '2', sx.ob->command_timeout);
3387 }
3388 else
3389 {
3390 /* Set up a pipe for proxying TLS for the new transport process */
3391
3392 smtp_peer_options |= PEER_OFFERED_TLS;
3393 if (sx.ok = (socketpair(AF_UNIX, SOCK_STREAM, 0, pfd) == 0))
3394 socket_fd = pfd[1];
3395 else
3396 set_errno(sx.first_addr, errno, US"internal allocation problem",
3397 DEFER, FALSE, host
3398 # ifdef EXPERIMENTAL_DSN_INFO
3399 , sx.smtp_greeting, sx.helo_response
3400 # endif
3401 );
3402 }
3403 #endif
3404
3405 /* If the socket is successfully passed, we mustn't send QUIT (or
3406 indeed anything!) from here. */
3407
3408 /*XXX DSN_INFO: assume likely to do new HELO; but for greet we'll want to
3409 propagate it from the initial
3410 */
3411 if (sx.ok && transport_pass_socket(tblock->name, host->name,
3412 host->address, new_message_id, socket_fd))
3413 {
3414 sx.send_quit = FALSE;
3415
3416 /* If TLS is still active, we need to proxy it for the transport we
3417 just passed the baton to. Fork a child to to do it, and return to
3418 get logging done asap. Which way to place the work makes assumptions
3419 about post-fork prioritisation which may not hold on all platforms. */
3420 #ifdef SUPPORT_TLS
3421 if (tls_out.active >= 0)
3422 {
3423 int pid = fork();
3424 if (pid > 0) /* parent */
3425 {
3426 waitpid(pid, NULL, 0);
3427 tls_close(FALSE, FALSE);
3428 (void)close(sx.inblock.sock);
3429 continue_transport = NULL;
3430 continue_hostname = NULL;
3431 return yield;
3432 }
3433 else if (pid == 0) /* child; fork again to disconnect totally */
3434 {
3435 if ((pid = fork()))
3436 _exit(pid ? EXIT_FAILURE : EXIT_SUCCESS);
3437 smtp_proxy_tls(sx.buffer, sizeof(sx.buffer), pfd[0], sx.ob->command_timeout);
3438 exim_exit(0);
3439 }
3440 }
3441 #endif
3442 }
3443 }
3444
3445 /* If RSET failed and there are addresses left, they get deferred. */
3446 else
3447 set_errno(sx.first_addr, errno, msg, DEFER, FALSE, host
3448 #ifdef EXPERIMENTAL_DSN_INFO
3449 , sx.smtp_greeting, sx.helo_response
3450 #endif
3451 );
3452 }
3453 }
3454
3455 /* End off tidily with QUIT unless the connection has died or the socket has
3456 been passed to another process. There has been discussion on the net about what
3457 to do after sending QUIT. The wording of the RFC suggests that it is necessary
3458 to wait for a response, but on the other hand, there isn't anything one can do
3459 with an error response, other than log it. Exim used to do that. However,
3460 further discussion suggested that it is positively advantageous not to wait for
3461 the response, but to close the session immediately. This is supposed to move
3462 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
3463 load from the server. (Hosts that are both servers and clients may not see much
3464 difference, of course.) Further discussion indicated that this was safe to do
3465 on Unix systems which have decent implementations of TCP/IP that leave the
3466 connection around for a while (TIME_WAIT) after the application has gone away.
3467 This enables the response sent by the server to be properly ACKed rather than
3468 timed out, as can happen on broken TCP/IP implementations on other OS.
3469
3470 This change is being made on 31-Jul-98. After over a year of trouble-free
3471 operation, the old commented-out code was removed on 17-Sep-99. */
3472
3473 SEND_QUIT:
3474 if (sx.send_quit) (void)smtp_write_command(&sx.outblock, FALSE, "QUIT\r\n");
3475
3476 END_OFF:
3477
3478 #ifdef SUPPORT_TLS
3479 tls_close(FALSE, TRUE);
3480 #endif
3481
3482 /* Close the socket, and return the appropriate value, first setting
3483 works because the NULL setting is passed back to the calling process, and
3484 remote_max_parallel is forced to 1 when delivering over an existing connection,
3485
3486 If all went well and continue_more is set, we shouldn't actually get here if
3487 there are further addresses, as the return above will be taken. However,
3488 writing RSET might have failed, or there may be other addresses whose hosts are
3489 specified in the transports, and therefore not visible at top level, in which
3490 case continue_more won't get set. */
3491
3492 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
3493 if (sx.send_quit)
3494 {
3495 shutdown(sx.outblock.sock, SHUT_WR);
3496 if (fcntl(sx.inblock.sock, F_SETFL, O_NONBLOCK) == 0)
3497 for (rc = 16; read(sx.inblock.sock, sx.inbuffer, sizeof(sx.inbuffer)) > 0 && rc > 0;)
3498 rc--; /* drain socket */
3499 }
3500 (void)close(sx.inblock.sock);
3501
3502 #ifndef DISABLE_EVENT
3503 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
3504 #endif
3505
3506 continue_transport = NULL;
3507 continue_hostname = NULL;
3508 return yield;
3509 }
3510
3511
3512
3513
3514 /*************************************************
3515 * Closedown entry point *
3516 *************************************************/
3517
3518 /* This function is called when exim is passed an open smtp channel
3519 from another incarnation, but the message which it has been asked
3520 to deliver no longer exists. The channel is on stdin.
3521
3522 We might do fancy things like looking for another message to send down
3523 the channel, but if the one we sought has gone, it has probably been
3524 delivered by some other process that itself will seek further messages,
3525 so just close down our connection.
3526
3527 Argument: pointer to the transport instance block
3528 Returns: nothing
3529 */
3530
3531 void
3532 smtp_transport_closedown(transport_instance *tblock)
3533 {
3534 smtp_transport_options_block *ob =
3535 (smtp_transport_options_block *)tblock->options_block;
3536 smtp_inblock inblock;
3537 smtp_outblock outblock;
3538 uschar buffer[256];
3539 uschar inbuffer[4096];
3540 uschar outbuffer[16];
3541
3542 inblock.sock = fileno(stdin);
3543 inblock.buffer = inbuffer;
3544 inblock.buffersize = sizeof(inbuffer);
3545 inblock.ptr = inbuffer;
3546 inblock.ptrend = inbuffer;
3547
3548 outblock.sock = inblock.sock;
3549 outblock.buffersize = sizeof(outbuffer);
3550 outblock.buffer = outbuffer;
3551 outblock.ptr = outbuffer;
3552 outblock.cmd_count = 0;
3553 outblock.authenticating = FALSE;
3554
3555 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
3556 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
3557 ob->command_timeout);
3558 (void)close(inblock.sock);
3559 }
3560
3561
3562
3563 /*************************************************
3564 * Prepare addresses for delivery *
3565 *************************************************/
3566
3567 /* This function is called to flush out error settings from previous delivery
3568 attempts to other hosts. It also records whether we got here via an MX record
3569 or not in the more_errno field of the address. We are interested only in
3570 addresses that are still marked DEFER - others may have got delivered to a
3571 previously considered IP address. Set their status to PENDING_DEFER to indicate
3572 which ones are relevant this time.
3573
3574 Arguments:
3575 addrlist the list of addresses
3576 host the host we are delivering to
3577
3578 Returns: the first address for this delivery
3579 */
3580
3581 static address_item *
3582 prepare_addresses(address_item *addrlist, host_item *host)
3583 {
3584 address_item *first_addr = NULL;
3585 address_item *addr;
3586 for (addr = addrlist; addr; addr = addr->next)
3587 if (addr->transport_return == DEFER)
3588 {
3589 if (!first_addr) first_addr = addr;
3590 addr->transport_return = PENDING_DEFER;
3591 addr->basic_errno = 0;
3592 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
3593 addr->message = NULL;
3594 #ifdef SUPPORT_TLS
3595 addr->cipher = NULL;
3596 addr->ourcert = NULL;
3597 addr->peercert = NULL;
3598 addr->peerdn = NULL;
3599 addr->ocsp = OCSP_NOT_REQ;
3600 #endif
3601 #ifdef EXPERIMENTAL_DSN_INFO
3602 addr->smtp_greeting = NULL;
3603 addr->helo_response = NULL;
3604 #endif
3605 }
3606 return first_addr;
3607 }
3608
3609
3610
3611 /*************************************************
3612 * Main entry point *
3613 *************************************************/
3614
3615 /* See local README for interface details. As this is a remote transport, it is
3616 given a chain of addresses to be delivered in one connection, if possible. It
3617 always returns TRUE, indicating that each address has its own independent
3618 status set, except if there is a setting up problem, in which case it returns
3619 FALSE. */
3620
3621 BOOL
3622 smtp_transport_entry(
3623 transport_instance *tblock, /* data for this instantiation */
3624 address_item *addrlist) /* addresses we are working on */
3625 {
3626 int cutoff_retry;
3627 int port;
3628 int hosts_defer = 0;
3629 int hosts_fail = 0;
3630 int hosts_looked_up = 0;
3631 int hosts_retry = 0;
3632 int hosts_serial = 0;
3633 int hosts_total = 0;
3634 int total_hosts_tried = 0;
3635 address_item *addr;
3636 BOOL expired = TRUE;
3637 uschar *expanded_hosts = NULL;
3638 uschar *pistring;
3639 uschar *tid = string_sprintf("%s transport", tblock->name);
3640 smtp_transport_options_block *ob =
3641 (smtp_transport_options_block *)(tblock->options_block);
3642 host_item *hostlist = addrlist->host_list;
3643 host_item *host = NULL;
3644
3645 DEBUG(D_transport)
3646 {
3647 debug_printf("%s transport entered\n", tblock->name);
3648 for (addr = addrlist; addr; addr = addr->next)
3649 debug_printf(" %s\n", addr->address);
3650 if (hostlist)
3651 {
3652 debug_printf("hostlist:\n");
3653 for (host = hostlist; host; host = host->next)
3654 debug_printf(" %s:%d\n", host->name, host->port);
3655 }
3656 if (continue_hostname)
3657 debug_printf("already connected to %s [%s] (on fd %d)\n",
3658 continue_hostname, continue_host_address,
3659 cutthrough.fd >= 0 ? cutthrough.fd : 0);
3660 }
3661
3662 /* Set the flag requesting that these hosts be added to the waiting
3663 database if the delivery fails temporarily or if we are running with
3664 queue_smtp or a 2-stage queue run. This gets unset for certain
3665 kinds of error, typically those that are specific to the message. */
3666
3667 update_waiting = TRUE;
3668
3669 /* If a host list is not defined for the addresses - they must all have the
3670 same one in order to be passed to a single transport - or if the transport has
3671 a host list with hosts_override set, use the host list supplied with the
3672 transport. It is an error for this not to exist. */
3673
3674 if (!hostlist || (ob->hosts_override && ob->hosts))
3675 {
3676 if (!ob->hosts)
3677 {
3678 addrlist->message = string_sprintf("%s transport called with no hosts set",
3679 tblock->name);
3680 addrlist->transport_return = PANIC;
3681 return FALSE; /* Only top address has status */
3682 }
3683
3684 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
3685 ob->hosts);
3686
3687 /* If the transport's host list contains no '$' characters, and we are not
3688 randomizing, it is fixed and therefore a chain of hosts can be built once
3689 and for all, and remembered for subsequent use by other calls to this
3690 transport. If, on the other hand, the host list does contain '$', or we are
3691 randomizing its order, we have to rebuild it each time. In the fixed case,
3692 as the hosts string will never be used again, it doesn't matter that we
3693 replace all the : characters with zeros. */
3694
3695 if (!ob->hostlist)
3696 {
3697 uschar *s = ob->hosts;
3698
3699 if (Ustrchr(s, '$') != NULL)
3700 {
3701 if (!(expanded_hosts = expand_string(s)))
3702 {
3703 addrlist->message = string_sprintf("failed to expand list of hosts "
3704 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
3705 addrlist->transport_return = search_find_defer ? DEFER : PANIC;
3706 return FALSE; /* Only top address has status */
3707 }
3708 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
3709 "\"%s\"\n", s, expanded_hosts);
3710 s = expanded_hosts;
3711 }
3712 else
3713 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
3714
3715 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
3716
3717 /* Check that the expansion yielded something useful. */
3718 if (!hostlist)
3719 {
3720 addrlist->message =
3721 string_sprintf("%s transport has empty hosts setting", tblock->name);
3722 addrlist->transport_return = PANIC;
3723 return FALSE; /* Only top address has status */
3724 }
3725
3726 /* If there was no expansion of hosts, save the host list for
3727 next time. */
3728
3729 if (!expanded_hosts) ob->hostlist = hostlist;
3730 }
3731
3732 /* This is not the first time this transport has been run in this delivery;
3733 the host list was built previously. */
3734
3735 else
3736 hostlist = ob->hostlist;
3737 }
3738
3739 /* The host list was supplied with the address. If hosts_randomize is set, we
3740 must sort it into a random order if it did not come from MX records and has not
3741 already been randomized (but don't bother if continuing down an existing
3742 connection). */
3743
3744 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continue_hostname)
3745 {
3746 host_item *newlist = NULL;
3747 while (hostlist)
3748 {
3749 host_item *h = hostlist;
3750 hostlist = hostlist->next;
3751
3752 h->sort_key = random_number(100);
3753
3754 if (!newlist)
3755 {
3756 h->next = NULL;
3757 newlist = h;
3758 }
3759 else if (h->sort_key < newlist->sort_key)
3760 {
3761 h->next = newlist;
3762 newlist = h;
3763 }
3764 else
3765 {
3766 host_item *hh = newlist;
3767 while (hh->next)
3768 {
3769 if (h->sort_key < hh->next->sort_key) break;
3770 hh = hh->next;
3771 }
3772 h->next = hh->next;
3773 hh->next = h;
3774 }
3775 }
3776
3777 hostlist = addrlist->host_list = newlist;
3778 }
3779
3780 /* Sort out the default port. */
3781
3782 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
3783
3784 /* For each host-plus-IP-address on the list:
3785
3786 . If this is a continued delivery and the host isn't the one with the
3787 current connection, skip.
3788
3789 . If the status is unusable (i.e. previously failed or retry checked), skip.
3790
3791 . If no IP address set, get the address, either by turning the name into
3792 an address, calling gethostbyname if gethostbyname is on, or by calling
3793 the DNS. The DNS may yield multiple addresses, in which case insert the
3794 extra ones into the list.
3795
3796 . Get the retry data if not previously obtained for this address and set the
3797 field which remembers the state of this address. Skip if the retry time is
3798 not reached. If not, remember whether retry data was found. The retry string
3799 contains both the name and the IP address.
3800
3801 . Scan the list of addresses and mark those whose status is DEFER as
3802 PENDING_DEFER. These are the only ones that will be processed in this cycle
3803 of the hosts loop.
3804
3805 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
3806 Some addresses may be successfully delivered, others may fail, and yet
3807 others may get temporary errors and so get marked DEFER.
3808
3809 . The return from the delivery attempt is OK if a connection was made and a
3810 valid SMTP dialogue was completed. Otherwise it is DEFER.
3811
3812 . If OK, add a "remove" retry item for this host/IPaddress, if any.
3813
3814 . If fail to connect, or other defer state, add a retry item.
3815
3816 . If there are any addresses whose status is still DEFER, carry on to the
3817 next host/IPaddress, unless we have tried the number of hosts given
3818 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
3819 there is some fancy logic for hosts_max_try that means its limit can be
3820 overstepped in some circumstances.
3821
3822 If we get to the end of the list, all hosts have deferred at least one address,
3823 or not reached their retry times. If delay_after_cutoff is unset, it requests a
3824 delivery attempt to those hosts whose last try was before the arrival time of
3825 the current message. To cope with this, we have to go round the loop a second
3826 time. After that, set the status and error data for any addresses that haven't
3827 had it set already. */
3828
3829 for (cutoff_retry = 0;
3830 expired && cutoff_retry < (ob->delay_after_cutoff ? 1 : 2);
3831 cutoff_retry++)
3832 {
3833 host_item *nexthost = NULL;
3834 int unexpired_hosts_tried = 0;
3835
3836 for (host = hostlist;
3837 host
3838 && unexpired_hosts_tried < ob->hosts_max_try
3839 && total_hosts_tried < ob->hosts_max_try_hardlimit;
3840 host = nexthost)
3841 {
3842 int rc;
3843 int host_af;
3844 uschar *rs;
3845 BOOL host_is_expired = FALSE;
3846 BOOL message_defer = FALSE;
3847 BOOL some_deferred = FALSE;
3848 address_item *first_addr = NULL;
3849 uschar *interface = NULL;
3850 uschar *retry_host_key = NULL;
3851 uschar *retry_message_key = NULL;
3852 uschar *serialize_key = NULL;
3853
3854 /* Default next host is next host. :-) But this can vary if the
3855 hosts_max_try limit is hit (see below). It may also be reset if a host
3856 address is looked up here (in case the host was multihomed). */
3857
3858 nexthost = host->next;
3859
3860 /* If the address hasn't yet been obtained from the host name, look it up
3861 now, unless the host is already marked as unusable. If it is marked as
3862 unusable, it means that the router was unable to find its IP address (in
3863 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
3864 the lookup failed last time. We don't get this far if *all* MX records
3865 point to non-existent hosts; that is treated as a hard error.
3866
3867 We can just skip this host entirely. When the hosts came from the router,
3868 the address will timeout based on the other host(s); when the address is
3869 looked up below, there is an explicit retry record added.
3870
3871 Note that we mustn't skip unusable hosts if the address is not unset; they
3872 may be needed as expired hosts on the 2nd time round the cutoff loop. */
3873
3874 if (!host->address)
3875 {
3876 int new_port, flags;
3877 host_item *hh;
3878
3879 if (host->status >= hstatus_unusable)
3880 {
3881 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
3882 host->name);
3883 continue;
3884 }
3885
3886 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
3887
3888 /* The host name is permitted to have an attached port. Find it, and
3889 strip it from the name. Just remember it for now. */
3890
3891 new_port = host_item_get_port(host);
3892
3893 /* Count hosts looked up */
3894
3895 hosts_looked_up++;
3896
3897 /* Find by name if so configured, or if it's an IP address. We don't
3898 just copy the IP address, because we need the test-for-local to happen. */
3899
3900 flags = HOST_FIND_BY_A;
3901 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
3902 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
3903
3904 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
3905 rc = host_find_byname(host, NULL, flags, NULL, TRUE);
3906 else
3907 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
3908 &ob->dnssec, /* domains for request/require */
3909 NULL, NULL);
3910
3911 /* Update the host (and any additional blocks, resulting from
3912 multihoming) with a host-specific port, if any. */
3913
3914 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
3915
3916 /* Failure to find the host at this time (usually DNS temporary failure)
3917 is really a kind of routing failure rather than a transport failure.
3918 Therefore we add a retry item of the routing kind, not to stop us trying
3919 to look this name up here again, but to ensure the address gets timed
3920 out if the failures go on long enough. A complete failure at this point
3921 commonly points to a configuration error, but the best action is still
3922 to carry on for the next host. */
3923
3924 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_SECURITY || rc == HOST_FIND_FAILED)
3925 {
3926 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
3927 expired = FALSE;
3928 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
3929 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
3930 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
3931 host->status = hstatus_unusable;
3932
3933 for (addr = addrlist; addr; addr = addr->next)
3934 {
3935 if (addr->transport_return != DEFER) continue;
3936 addr->basic_errno = ERRNO_UNKNOWNHOST;
3937 addr->message = string_sprintf(
3938 rc == HOST_FIND_SECURITY
3939 ? "lookup of IP address for %s was insecure"
3940 : "failed to lookup IP address for %s",
3941 host->name);
3942 }
3943 continue;
3944 }
3945
3946 /* If the host is actually the local host, we may have a problem, or
3947 there may be some cunning configuration going on. In the problem case,
3948 log things and give up. The default transport status is already DEFER. */
3949
3950 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
3951 {
3952 for (addr = addrlist; addr; addr = addr->next)
3953 {
3954 addr->basic_errno = 0;
3955 addr->message = string_sprintf("%s transport found host %s to be "
3956 "local", tblock->name, host->name);
3957 }
3958 goto END_TRANSPORT;
3959 }
3960 } /* End of block for IP address lookup */
3961
3962 /* If this is a continued delivery, we are interested only in the host
3963 which matches the name of the existing open channel. The check is put
3964 here after the local host lookup, in case the name gets expanded as a
3965 result of the lookup. Set expired FALSE, to save the outer loop executing
3966 twice. */
3967
3968 if ( continue_hostname
3969 && ( Ustrcmp(continue_hostname, host->name) != 0
3970 || Ustrcmp(continue_host_address, host->address) != 0
3971 ) )
3972 {
3973 expired = FALSE;
3974 continue; /* With next host */
3975 }
3976
3977 /* Reset the default next host in case a multihomed host whose addresses
3978 are not looked up till just above added to the host list. */
3979
3980 nexthost = host->next;
3981
3982 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
3983 domain is in queue_smtp_domains, we don't actually want to attempt any
3984 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
3985 there is a lookup defer in queue_smtp_domains, proceed as if the domain
3986 were not in it. We don't want to hold up all SMTP deliveries! Except when
3987 doing a two-stage queue run, don't do this if forcing. */
3988
3989 if ((!deliver_force || queue_2stage) && (queue_smtp ||
3990 match_isinlist(addrlist->domain,
3991 (const uschar **)&queue_smtp_domains, 0,
3992 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
3993 {
3994 expired = FALSE;
3995 for (addr = addrlist; addr; addr = addr->next)
3996 if (addr->transport_return == DEFER)
3997 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
3998 continue; /* With next host */
3999 }
4000
4001 /* Count hosts being considered - purely for an intelligent comment
4002 if none are usable. */
4003
4004 hosts_total++;
4005
4006 /* Set $host and $host address now in case they are needed for the
4007 interface expansion or the serialize_hosts check; they remain set if an
4008 actual delivery happens. */
4009
4010 deliver_host = host->name;
4011 deliver_host_address = host->address;
4012 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
4013 : host->dnssec == DS_NO ? US"no"
4014 : US"";
4015
4016 /* Set up a string for adding to the retry key if the port number is not
4017 the standard SMTP port. A host may have its own port setting that overrides
4018 the default. */
4019
4020 pistring = string_sprintf(":%d", host->port == PORT_NONE
4021 ? port : host->port);
4022 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
4023
4024 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
4025 string is set, even if constant (as different transports can have different
4026 constant settings), we must add it to the key that is used for retries,
4027 because connections to the same host from a different interface should be
4028 treated separately. */
4029
4030 host_af = Ustrchr(host->address, ':') == NULL ? AF_INET : AF_INET6;
4031 if ((rs = ob->interface) && *rs)
4032 {
4033 if (!smtp_get_interface(rs, host_af, addrlist, &interface, tid))
4034 return FALSE;
4035 pistring = string_sprintf("%s/%s", pistring, interface);
4036 }
4037
4038 /* The first time round the outer loop, check the status of the host by
4039 inspecting the retry data. The second time round, we are interested only
4040 in expired hosts that haven't been tried since this message arrived. */
4041
4042 if (cutoff_retry == 0)
4043 {
4044 BOOL incl_ip;
4045 /* Ensure the status of the address is set by checking retry data if
4046 necessary. There may be host-specific retry data (applicable to all
4047 messages) and also data for retries of a specific message at this host.
4048 If either of these retry records are actually read, the keys used are
4049 returned to save recomputing them later. */
4050
4051 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
4052 US"retry_include_ip_address", ob->retry_include_ip_address,
4053 ob->expand_retry_include_ip_address, &incl_ip) != OK)
4054 continue; /* with next host */
4055
4056 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
4057 incl_ip, &retry_host_key, &retry_message_key);
4058
4059 DEBUG(D_transport) debug_printf("%s [%s]%s retry-status = %s\n", host->name,
4060 (host->address == NULL)? US"" : host->address, pistring,
4061 (host->status == hstatus_usable)? "usable" :
4062 (host->status == hstatus_unusable)? "unusable" :
4063 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
4064
4065 /* Skip this address if not usable at this time, noting if it wasn't
4066 actually expired, both locally and in the address. */
4067
4068 switch (host->status)
4069 {
4070 case hstatus_unusable:
4071 expired = FALSE;
4072 setflag(addrlist, af_retry_skipped);
4073 /* Fall through */
4074
4075 case hstatus_unusable_expired:
4076 switch (host->why)
4077 {
4078 case hwhy_retry: hosts_retry++; break;
4079 case hwhy_failed: hosts_fail++; break;
4080 case hwhy_insecure:
4081 case hwhy_deferred: hosts_defer++; break;
4082 }
4083
4084 /* If there was a retry message key, implying that previously there
4085 was a message-specific defer, we don't want to update the list of
4086 messages waiting for these hosts. */
4087
4088 if (retry_message_key) update_waiting = FALSE;
4089 continue; /* With the next host or IP address */
4090 }
4091 }
4092
4093 /* Second time round the loop: if the address is set but expired, and
4094 the message is newer than the last try, let it through. */
4095
4096 else
4097 {
4098 if ( !host->address
4099 || host->status != hstatus_unusable_expired
4100 || host->last_try > received_time)
4101 continue;
4102 DEBUG(D_transport) debug_printf("trying expired host %s [%s]%s\n",
4103 host->name, host->address, pistring);
4104 host_is_expired = TRUE;
4105 }
4106
4107 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
4108 it remains TRUE only if all hosts are expired and none are actually tried.
4109 */
4110
4111 expired = FALSE;
4112
4113 /* If this host is listed as one to which access must be serialized,
4114 see if another Exim process has a connection to it, and if so, skip
4115 this host. If not, update the database to record our connection to it
4116 and remember this for later deletion. Do not do any of this if we are
4117 sending the message down a pre-existing connection. */
4118
4119 if ( !continue_hostname
4120 && verify_check_given_host(&ob->serialize_hosts, host) == OK)
4121 {
4122 serialize_key = string_sprintf("host-serialize-%s", host->name);
4123 if (!enq_start(serialize_key, 1))
4124 {
4125 DEBUG(D_transport)
4126 debug_printf("skipping host %s because another Exim process "
4127 "is connected to it\n", host->name);
4128 hosts_serial++;
4129 continue;
4130 }
4131 }
4132
4133 /* OK, we have an IP address that is not waiting for its retry time to
4134 arrive (it might be expired) OR (second time round the loop) we have an
4135 expired host that hasn't been tried since the message arrived. Have a go
4136 at delivering the message to it. First prepare the addresses by flushing
4137 out the result of previous attempts, and finding the first address that
4138 is still to be delivered. */
4139
4140 first_addr = prepare_addresses(addrlist, host);
4141
4142 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
4143 message_id, host->name, host->address, addrlist->address,
4144 addrlist->next ? ", ..." : "");
4145
4146 set_process_info("delivering %s to %s [%s] (%s%s)",
4147 message_id, host->name, host->address, addrlist->address,
4148 addrlist->next ? ", ..." : "");
4149
4150 /* This is not for real; don't do the delivery. If there are
4151 any remaining hosts, list them. */
4152
4153 if (dont_deliver)
4154 {
4155 host_item *host2;
4156 set_errno_nohost(addrlist, 0, NULL, OK, FALSE);
4157 for (addr = addrlist; addr; addr = addr->next)
4158 {
4159 addr->host_used = host;
4160 addr->special_action = '*';
4161 addr->message = US"delivery bypassed by -N option";
4162 }
4163 DEBUG(D_transport)
4164 {
4165 debug_printf("*** delivery by %s transport bypassed by -N option\n"
4166 "*** host and remaining hosts:\n", tblock->name);
4167 for (host2 = host; host2; host2 = host2->next)
4168 debug_printf(" %s [%s]\n", host2->name,
4169 host2->address ? host2->address : US"unset");
4170 }
4171 rc = OK;
4172 }
4173
4174 /* This is for real. If the host is expired, we don't count it for
4175 hosts_max_retry. This ensures that all hosts must expire before an address
4176 is timed out, unless hosts_max_try_hardlimit (which protects against
4177 lunatic DNS configurations) is reached.
4178
4179 If the host is not expired and we are about to hit the hosts_max_retry
4180 limit, check to see if there is a subsequent hosts with a different MX
4181 value. If so, make that the next host, and don't count this one. This is a
4182 heuristic to make sure that different MXs do get tried. With a normal kind
4183 of retry rule, they would get tried anyway when the earlier hosts were
4184 delayed, but if the domain has a "retry every time" type of rule - as is
4185 often used for the the very large ISPs, that won't happen. */
4186
4187 else
4188 {
4189 host_item * thost;
4190 /* Make a copy of the host if it is local to this invocation
4191 of the transport. */
4192
4193 if (expanded_hosts)
4194 {
4195 thost = store_get(sizeof(host_item));
4196 *thost = *host;
4197 thost->name = string_copy(host->name);
4198 thost->address = string_copy(host->address);
4199 }
4200 else
4201 thost = host;
4202
4203 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
4204 {
4205 host_item *h;
4206 DEBUG(D_transport)
4207 debug_printf("hosts_max_try limit reached with this host\n");
4208 for (h = host; h; h = h->next) if (h->mx != host->mx)
4209 {
4210 nexthost = h;
4211 unexpired_hosts_tried--;
4212 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
4213 "and will be tried\n");
4214 break;
4215 }
4216 }
4217
4218 /* Attempt the delivery. */
4219
4220 total_hosts_tried++;
4221 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
4222 &message_defer, FALSE);
4223
4224 /* Yield is one of:
4225 OK => connection made, each address contains its result;
4226 message_defer is set for message-specific defers (when all
4227 recipients are marked defer)
4228 DEFER => there was a non-message-specific delivery problem;
4229 ERROR => there was a problem setting up the arguments for a filter,
4230 or there was a problem with expanding added headers
4231 */
4232
4233 /* If the result is not OK, there was a non-message-specific problem.
4234 If the result is DEFER, we need to write to the logs saying what happened
4235 for this particular host, except in the case of authentication and TLS
4236 failures, where the log has already been written. If all hosts defer a
4237 general message is written at the end. */
4238
4239 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL
4240 && first_addr->basic_errno != ERRNO_TLSFAILURE)
4241 write_logs(first_addr, host);
4242
4243 #ifndef DISABLE_EVENT
4244 if (rc == DEFER)
4245 deferred_event_raise(first_addr, host);
4246 #endif
4247
4248 /* If STARTTLS was accepted, but there was a failure in setting up the
4249 TLS session (usually a certificate screwup), and the host is not in
4250 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
4251 TLS forcibly turned off. We have to start from scratch with a new SMTP
4252 connection. That's why the retry is done from here, not from within
4253 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
4254 session, so the in-clear transmission after those errors, if permitted,
4255 happens inside smtp_deliver().] */
4256
4257 #ifdef SUPPORT_TLS
4258 if ( rc == DEFER
4259 && first_addr->basic_errno == ERRNO_TLSFAILURE
4260 && ob->tls_tempfail_tryclear
4261 && verify_check_given_host(&ob->hosts_require_tls, host) != OK
4262 )
4263 {
4264 log_write(0, LOG_MAIN,
4265 "%s: delivering unencrypted to H=%s [%s] (not in hosts_require_tls)",
4266 first_addr->message, host->name, host->address);
4267 first_addr = prepare_addresses(addrlist, host);
4268 rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
4269 &message_defer, TRUE);
4270 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
4271 write_logs(first_addr, host);
4272 # ifndef DISABLE_EVENT
4273 if (rc == DEFER)
4274 deferred_event_raise(first_addr, host);
4275 # endif
4276 }
4277 #endif /*SUPPORT_TLS*/
4278 }
4279
4280 /* Delivery attempt finished */
4281
4282 rs = rc == OK ? US"OK"
4283 : rc == DEFER ? US"DEFER"
4284 : rc == ERROR ? US"ERROR"
4285 : US"?";
4286
4287 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
4288 message_id, host->name, host->address, addrlist->address,
4289 addrlist->next ? " (& others)" : "", rs);
4290
4291 /* Release serialization if set up */
4292
4293 if (serialize_key) enq_end(serialize_key);
4294
4295 /* If the result is DEFER, or if a host retry record is known to exist, we
4296 need to add an item to the retry chain for updating the retry database
4297 at the end of delivery. We only need to add the item to the top address,
4298 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
4299 for any other delivery attempts using the same address. (It is copied into
4300 the unusable tree at the outer level, so even if different address blocks
4301 contain the same address, it still won't get tried again.) */
4302
4303 if (rc == DEFER || retry_host_key)
4304 {
4305 int delete_flag = rc != DEFER ? rf_delete : 0;
4306 if (!retry_host_key)
4307 {
4308 BOOL incl_ip;
4309 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
4310 US"retry_include_ip_address", ob->retry_include_ip_address,
4311 ob->expand_retry_include_ip_address, &incl_ip) != OK)
4312 incl_ip = TRUE; /* error; use most-specific retry record */
4313
4314 retry_host_key = incl_ip
4315 ? string_sprintf("T:%S:%s%s", host->name, host->address, pistring)
4316 : string_sprintf("T:%S%s", host->name, pistring);
4317 }
4318
4319 /* If a delivery of another message over an existing SMTP connection
4320 yields DEFER, we do NOT set up retry data for the host. This covers the
4321 case when there are delays in routing the addresses in the second message
4322 that are so long that the server times out. This is alleviated by not
4323 routing addresses that previously had routing defers when handling an
4324 existing connection, but even so, this case may occur (e.g. if a
4325 previously happily routed address starts giving routing defers). If the
4326 host is genuinely down, another non-continued message delivery will
4327 notice it soon enough. */
4328
4329 if (delete_flag != 0 || !continue_hostname)
4330 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
4331
4332 /* We may have tried an expired host, if its retry time has come; ensure
4333 the status reflects the expiry for the benefit of any other addresses. */
4334
4335 if (rc == DEFER)
4336 {
4337 host->status = host_is_expired
4338 ? hstatus_unusable_expired : hstatus_unusable;
4339 host->why = hwhy_deferred;
4340 }
4341 }
4342
4343 /* If message_defer is set (host was OK, but every recipient got deferred
4344 because of some message-specific problem), or if that had happened
4345 previously so that a message retry key exists, add an appropriate item
4346 to the retry chain. Note that if there was a message defer but now there is
4347 a host defer, the message defer record gets deleted. That seems perfectly
4348 reasonable. Also, stop the message from being remembered as waiting
4349 for specific hosts. */
4350
4351 if (message_defer || retry_message_key)
4352 {
4353 int delete_flag = message_defer ? 0 : rf_delete;
4354 if (!retry_message_key)
4355 {
4356 BOOL incl_ip;
4357 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
4358 US"retry_include_ip_address", ob->retry_include_ip_address,
4359 ob->expand_retry_include_ip_address, &incl_ip) != OK)
4360 incl_ip = TRUE; /* error; use most-specific retry record */
4361
4362 retry_message_key = incl_ip
4363 ? string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
4364 message_id)
4365 : string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
4366 }
4367 retry_add_item(addrlist, retry_message_key,
4368 rf_message | rf_host | delete_flag);
4369 update_waiting = FALSE;
4370 }
4371
4372 /* Any return other than DEFER (that is, OK or ERROR) means that the
4373 addresses have got their final statuses filled in for this host. In the OK
4374 case, see if any of them are deferred. */
4375
4376 if (rc == OK)
4377 for (addr = addrlist; addr; addr = addr->next)
4378 if (addr->transport_return == DEFER)
4379 {
4380 some_deferred = TRUE;
4381 break;
4382 }
4383
4384 /* If no addresses deferred or the result was ERROR, return. We do this for
4385 ERROR because a failing filter set-up or add_headers expansion is likely to
4386 fail for any host we try. */
4387
4388 if (rc == ERROR || (rc == OK && !some_deferred))
4389 {
4390 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
4391 return TRUE; /* Each address has its status */
4392 }
4393
4394 /* If the result was DEFER or some individual addresses deferred, let
4395 the loop run to try other hosts with the deferred addresses, except for the
4396 case when we were trying to deliver down an existing channel and failed.
4397 Don't try any other hosts in this case. */
4398
4399 if (continue_hostname) break;
4400
4401 /* If the whole delivery, or some individual addresses, were deferred and
4402 there are more hosts that could be tried, do not count this host towards
4403 the hosts_max_try limit if the age of the message is greater than the
4404 maximum retry time for this host. This means we may try try all hosts,
4405 ignoring the limit, when messages have been around for some time. This is
4406 important because if we don't try all hosts, the address will never time
4407 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
4408
4409 if ((rc == DEFER || some_deferred) && nexthost)
4410 {
4411 BOOL timedout;
4412 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
4413
4414 if (retry && retry->rules)
4415 {
4416 retry_rule *last_rule;
4417 for (last_rule = retry->rules;
4418 last_rule->next;
4419 last_rule = last_rule->next);
4420 timedout = time(NULL) - received_time > last_rule->timeout;
4421 }
4422 else timedout = TRUE; /* No rule => timed out */
4423
4424 if (timedout)
4425 {
4426 unexpired_hosts_tried--;
4427 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
4428 "hosts_max_try (message older than host's retry time)\n");
4429 }
4430 }
4431 } /* End of loop for trying multiple hosts. */
4432
4433 /* This is the end of the loop that repeats iff expired is TRUE and
4434 ob->delay_after_cutoff is FALSE. The second time round we will
4435 try those hosts that haven't been tried since the message arrived. */
4436
4437 DEBUG(D_transport)
4438 {
4439 debug_printf("all IP addresses skipped or deferred at least one address\n");
4440 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
4441 debug_printf("retrying IP addresses not tried since message arrived\n");
4442 }
4443 }
4444
4445
4446 /* Get here if all IP addresses are skipped or defer at least one address. In
4447 MUA wrapper mode, this will happen only for connection or other non-message-
4448 specific failures. Force the delivery status for all addresses to FAIL. */
4449
4450 if (mua_wrapper)
4451 {
4452 for (addr = addrlist; addr; addr = addr->next)
4453 addr->transport_return = FAIL;
4454 goto END_TRANSPORT;
4455 }
4456
4457 /* In the normal, non-wrapper case, add a standard message to each deferred
4458 address if there hasn't been an error, that is, if it hasn't actually been
4459 tried this time. The variable "expired" will be FALSE if any deliveries were
4460 actually tried, or if there was at least one host that was not expired. That
4461 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
4462 a delivery has been tried, an error code will be set, and the failing of the
4463 message is handled by the retry code later.
4464
4465 If queue_smtp is set, or this transport was called to send a subsequent message
4466 down an existing TCP/IP connection, and something caused the host not to be
4467 found, we end up here, but can detect these cases and handle them specially. */
4468
4469 for (addr = addrlist; addr; addr = addr->next)
4470 {
4471 /* If host is not NULL, it means that we stopped processing the host list
4472 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
4473 means we need to behave as if some hosts were skipped because their retry
4474 time had not come. Specifically, this prevents the address from timing out.
4475 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
4476 hosts were tried. */
4477
4478 if (host)
4479 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
4480 {
4481 DEBUG(D_transport)
4482 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
4483 "hosts were tried\n");
4484 }
4485 else
4486 {
4487 DEBUG(D_transport)
4488 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
4489 setflag(addr, af_retry_skipped);
4490 }
4491
4492 if (queue_smtp) /* no deliveries attempted */
4493 {
4494 addr->transport_return = DEFER;
4495 addr->basic_errno = 0;
4496 addr->message = US"SMTP delivery explicitly queued";
4497 }
4498
4499 else if ( addr->transport_return == DEFER
4500 && (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0)
4501 && !addr->message
4502 )
4503 {
4504 addr->basic_errno = ERRNO_HRETRY;
4505 if (continue_hostname)
4506 addr->message = US"no host found for existing SMTP connection";
4507 else if (expired)
4508 {
4509 setflag(addr, af_pass_message); /* This is not a security risk */
4510 addr->message = string_sprintf(
4511 "all hosts%s have been failing for a long time %s",
4512 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"",
4513 ob->delay_after_cutoff
4514 ? US"(and retry time not reached)"
4515 : US"and were last tried after this message arrived");
4516
4517 /* If we are already using fallback hosts, or there are no fallback hosts
4518 defined, convert the result to FAIL to cause a bounce. */
4519
4520 if (addr->host_list == addr->fallback_hosts || !addr->fallback_hosts)
4521 addr->transport_return = FAIL;
4522 }
4523 else
4524 {
4525 const char * s;
4526 if (hosts_retry == hosts_total)
4527 s = "retry time not reached for any host%s";
4528 else if (hosts_fail == hosts_total)
4529 s = "all host address lookups%s failed permanently";
4530 else if (hosts_defer == hosts_total)
4531 s = "all host address lookups%s failed temporarily";
4532 else if (hosts_serial == hosts_total)
4533 s = "connection limit reached for all hosts%s";
4534 else if (hosts_fail+hosts_defer == hosts_total)
4535 s = "all host address lookups%s failed";
4536 else
4537 s = "some host address lookups failed and retry time "
4538 "not reached for other hosts or connection limit reached%s";
4539
4540 addr->message = string_sprintf(s,
4541 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"");
4542 }
4543 }
4544 }
4545
4546 /* Update the database which keeps information about which messages are waiting
4547 for which hosts to become available. For some message-specific errors, the
4548 update_waiting flag is turned off because we don't want follow-on deliveries in
4549 those cases. If this transport instance is explicitly limited to one message
4550 per connection then follow-on deliveries are not possible and there's no need
4551 to create/update the per-transport wait-<transport_name> database. */
4552
4553 if (update_waiting && tblock->connection_max_messages != 1)
4554 transport_update_waiting(hostlist, tblock->name);
4555
4556 END_TRANSPORT:
4557
4558 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
4559
4560 return TRUE; /* Each address has its status */
4561 }
4562
4563 /* vi: aw ai sw=2
4564 */
4565 /* End of transport/smtp.c */