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Propagate more error codes internally
[exim.git] / src / src / transports / smtp.c
1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
4
5 /* Copyright (c) University of Cambridge 1995 - 2014 */
6 /* See the file NOTICE for conditions of use and distribution. */
7
8 #include "../exim.h"
9 #include "smtp.h"
10
11 #define PENDING 256
12 #define PENDING_DEFER (PENDING + DEFER)
13 #define PENDING_OK (PENDING + OK)
14
15
16 /* Options specific to the smtp transport. This transport also supports LMTP
17 over TCP/IP. The options must be in alphabetic order (note that "_" comes
18 before the lower case letters). Some live in the transport_instance block so as
19 to be publicly visible; these are flagged with opt_public. */
20
21 optionlist smtp_transport_options[] = {
22 { "*expand_multi_domain", opt_stringptr | opt_hidden | opt_public,
23 (void *)offsetof(transport_instance, expand_multi_domain) },
24 { "*expand_retry_include_ip_address", opt_stringptr | opt_hidden,
25 (void *)(offsetof(smtp_transport_options_block, expand_retry_include_ip_address)) },
26
27 { "address_retry_include_sender", opt_bool,
28 (void *)offsetof(smtp_transport_options_block, address_retry_include_sender) },
29 { "allow_localhost", opt_bool,
30 (void *)offsetof(smtp_transport_options_block, allow_localhost) },
31 { "authenticated_sender", opt_stringptr,
32 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
33 { "authenticated_sender_force", opt_bool,
34 (void *)offsetof(smtp_transport_options_block, authenticated_sender_force) },
35 { "command_timeout", opt_time,
36 (void *)offsetof(smtp_transport_options_block, command_timeout) },
37 { "connect_timeout", opt_time,
38 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
39 { "connection_max_messages", opt_int | opt_public,
40 (void *)offsetof(transport_instance, connection_max_messages) },
41 { "data_timeout", opt_time,
42 (void *)offsetof(smtp_transport_options_block, data_timeout) },
43 { "delay_after_cutoff", opt_bool,
44 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
45 #ifndef DISABLE_DKIM
46 { "dkim_canon", opt_stringptr,
47 (void *)offsetof(smtp_transport_options_block, dkim_canon) },
48 { "dkim_domain", opt_stringptr,
49 (void *)offsetof(smtp_transport_options_block, dkim_domain) },
50 { "dkim_private_key", opt_stringptr,
51 (void *)offsetof(smtp_transport_options_block, dkim_private_key) },
52 { "dkim_selector", opt_stringptr,
53 (void *)offsetof(smtp_transport_options_block, dkim_selector) },
54 { "dkim_sign_headers", opt_stringptr,
55 (void *)offsetof(smtp_transport_options_block, dkim_sign_headers) },
56 { "dkim_strict", opt_stringptr,
57 (void *)offsetof(smtp_transport_options_block, dkim_strict) },
58 #endif
59 { "dns_qualify_single", opt_bool,
60 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
61 { "dns_search_parents", opt_bool,
62 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
63 { "dnssec_request_domains", opt_stringptr,
64 (void *)offsetof(smtp_transport_options_block, dnssec_request_domains) },
65 { "dnssec_require_domains", opt_stringptr,
66 (void *)offsetof(smtp_transport_options_block, dnssec_require_domains) },
67 { "dscp", opt_stringptr,
68 (void *)offsetof(smtp_transport_options_block, dscp) },
69 { "fallback_hosts", opt_stringptr,
70 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
71 { "final_timeout", opt_time,
72 (void *)offsetof(smtp_transport_options_block, final_timeout) },
73 { "gethostbyname", opt_bool,
74 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
75 #ifdef SUPPORT_TLS
76 /* These are no longer honoured, as of Exim 4.80; for now, we silently
77 ignore; 4.83 will warn, and a later-still release will remove
78 these options, so that using them becomes an error. */
79 { "gnutls_require_kx", opt_stringptr,
80 (void *)offsetof(smtp_transport_options_block, gnutls_require_kx) },
81 { "gnutls_require_mac", opt_stringptr,
82 (void *)offsetof(smtp_transport_options_block, gnutls_require_mac) },
83 { "gnutls_require_protocols", opt_stringptr,
84 (void *)offsetof(smtp_transport_options_block, gnutls_require_proto) },
85 #endif
86 { "helo_data", opt_stringptr,
87 (void *)offsetof(smtp_transport_options_block, helo_data) },
88 { "hosts", opt_stringptr,
89 (void *)offsetof(smtp_transport_options_block, hosts) },
90 { "hosts_avoid_esmtp", opt_stringptr,
91 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
92 { "hosts_avoid_pipelining", opt_stringptr,
93 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
94 #ifdef SUPPORT_TLS
95 { "hosts_avoid_tls", opt_stringptr,
96 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
97 #endif
98 { "hosts_max_try", opt_int,
99 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
100 { "hosts_max_try_hardlimit", opt_int,
101 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
102 #ifdef SUPPORT_TLS
103 { "hosts_nopass_tls", opt_stringptr,
104 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
105 #endif
106 { "hosts_override", opt_bool,
107 (void *)offsetof(smtp_transport_options_block, hosts_override) },
108 { "hosts_randomize", opt_bool,
109 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
110 #if defined(SUPPORT_TLS) && !defined(DISABLE_OCSP)
111 { "hosts_request_ocsp", opt_stringptr,
112 (void *)offsetof(smtp_transport_options_block, hosts_request_ocsp) },
113 #endif
114 { "hosts_require_auth", opt_stringptr,
115 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
116 #ifdef SUPPORT_TLS
117 # ifdef EXPERIMENTAL_DANE
118 { "hosts_require_dane", opt_stringptr,
119 (void *)offsetof(smtp_transport_options_block, hosts_require_dane) },
120 # endif
121 # ifndef DISABLE_OCSP
122 { "hosts_require_ocsp", opt_stringptr,
123 (void *)offsetof(smtp_transport_options_block, hosts_require_ocsp) },
124 # endif
125 { "hosts_require_tls", opt_stringptr,
126 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
127 #endif
128 { "hosts_try_auth", opt_stringptr,
129 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
130 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
131 { "hosts_try_dane", opt_stringptr,
132 (void *)offsetof(smtp_transport_options_block, hosts_try_dane) },
133 #endif
134 #ifndef DISABLE_PRDR
135 { "hosts_try_prdr", opt_stringptr,
136 (void *)offsetof(smtp_transport_options_block, hosts_try_prdr) },
137 #endif
138 #ifdef SUPPORT_TLS
139 { "hosts_verify_avoid_tls", opt_stringptr,
140 (void *)offsetof(smtp_transport_options_block, hosts_verify_avoid_tls) },
141 #endif
142 { "interface", opt_stringptr,
143 (void *)offsetof(smtp_transport_options_block, interface) },
144 { "keepalive", opt_bool,
145 (void *)offsetof(smtp_transport_options_block, keepalive) },
146 { "lmtp_ignore_quota", opt_bool,
147 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
148 { "max_rcpt", opt_int | opt_public,
149 (void *)offsetof(transport_instance, max_addresses) },
150 { "multi_domain", opt_expand_bool | opt_public,
151 (void *)offsetof(transport_instance, multi_domain) },
152 { "port", opt_stringptr,
153 (void *)offsetof(smtp_transport_options_block, port) },
154 { "protocol", opt_stringptr,
155 (void *)offsetof(smtp_transport_options_block, protocol) },
156 { "retry_include_ip_address", opt_expand_bool,
157 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
158 { "serialize_hosts", opt_stringptr,
159 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
160 { "size_addition", opt_int,
161 (void *)offsetof(smtp_transport_options_block, size_addition) }
162 #ifdef SUPPORT_TLS
163 ,{ "tls_certificate", opt_stringptr,
164 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
165 { "tls_crl", opt_stringptr,
166 (void *)offsetof(smtp_transport_options_block, tls_crl) },
167 { "tls_dh_min_bits", opt_int,
168 (void *)offsetof(smtp_transport_options_block, tls_dh_min_bits) },
169 { "tls_privatekey", opt_stringptr,
170 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
171 { "tls_require_ciphers", opt_stringptr,
172 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
173 { "tls_sni", opt_stringptr,
174 (void *)offsetof(smtp_transport_options_block, tls_sni) },
175 { "tls_tempfail_tryclear", opt_bool,
176 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
177 { "tls_try_verify_hosts", opt_stringptr,
178 (void *)offsetof(smtp_transport_options_block, tls_try_verify_hosts) },
179 { "tls_verify_cert_hostnames", opt_stringptr,
180 (void *)offsetof(smtp_transport_options_block,tls_verify_cert_hostnames)},
181 { "tls_verify_certificates", opt_stringptr,
182 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) },
183 { "tls_verify_hosts", opt_stringptr,
184 (void *)offsetof(smtp_transport_options_block, tls_verify_hosts) }
185 #endif
186 };
187
188 /* Size of the options list. An extern variable has to be used so that its
189 address can appear in the tables drtables.c. */
190
191 int smtp_transport_options_count =
192 sizeof(smtp_transport_options)/sizeof(optionlist);
193
194 /* Default private options block for the smtp transport. */
195
196 smtp_transport_options_block smtp_transport_option_defaults = {
197 NULL, /* hosts */
198 NULL, /* fallback_hosts */
199 NULL, /* hostlist */
200 NULL, /* fallback_hostlist */
201 NULL, /* authenticated_sender */
202 US"$primary_hostname", /* helo_data */
203 NULL, /* interface */
204 NULL, /* port */
205 US"smtp", /* protocol */
206 NULL, /* DSCP */
207 NULL, /* serialize_hosts */
208 NULL, /* hosts_try_auth */
209 NULL, /* hosts_require_auth */
210 #ifdef EXPERIMENTAL_DANE
211 NULL, /* hosts_try_dane */
212 NULL, /* hosts_require_dane */
213 #endif
214 #ifndef DISABLE_PRDR
215 US"*", /* hosts_try_prdr */
216 #endif
217 #ifndef DISABLE_OCSP
218 US"*", /* hosts_request_ocsp (except under DANE; tls_client_start()) */
219 NULL, /* hosts_require_ocsp */
220 #endif
221 NULL, /* hosts_require_tls */
222 NULL, /* hosts_avoid_tls */
223 US"*", /* hosts_verify_avoid_tls */
224 NULL, /* hosts_avoid_pipelining */
225 NULL, /* hosts_avoid_esmtp */
226 NULL, /* hosts_nopass_tls */
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, /* dnssec_request_domains */
241 NULL, /* dnssec_require_domains */
242 TRUE, /* delay_after_cutoff */
243 FALSE, /* hosts_override */
244 FALSE, /* hosts_randomize */
245 TRUE, /* keepalive */
246 FALSE, /* lmtp_ignore_quota */
247 NULL, /* expand_retry_include_ip_address */
248 TRUE /* retry_include_ip_address */
249 #ifdef SUPPORT_TLS
250 ,NULL, /* tls_certificate */
251 NULL, /* tls_crl */
252 NULL, /* tls_privatekey */
253 NULL, /* tls_require_ciphers */
254 NULL, /* gnutls_require_kx */
255 NULL, /* gnutls_require_mac */
256 NULL, /* gnutls_require_proto */
257 NULL, /* tls_sni */
258 US"system", /* tls_verify_certificates */
259 EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
260 /* tls_dh_min_bits */
261 TRUE, /* tls_tempfail_tryclear */
262 NULL, /* tls_verify_hosts */
263 US"*", /* tls_try_verify_hosts */
264 US"*" /* tls_verify_cert_hostnames */
265 #endif
266 #ifndef DISABLE_DKIM
267 ,NULL, /* dkim_canon */
268 NULL, /* dkim_domain */
269 NULL, /* dkim_private_key */
270 NULL, /* dkim_selector */
271 NULL, /* dkim_sign_headers */
272 NULL /* dkim_strict */
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 BOOL update_waiting; /* TRUE to update the "wait" database */
290
291
292 /*************************************************
293 * Setup entry point *
294 *************************************************/
295
296 /* This function is called when the transport is about to be used,
297 but before running it in a sub-process. It is used for two things:
298
299 (1) To set the fallback host list in addresses, when delivering.
300 (2) To pass back the interface, port, protocol, and other options, for use
301 during callout verification.
302
303 Arguments:
304 tblock pointer to the transport instance block
305 addrlist list of addresses about to be transported
306 tf if not NULL, pointer to block in which to return options
307 uid the uid that will be set (not used)
308 gid the gid that will be set (not used)
309 errmsg place for error message (not used)
310
311 Returns: OK always (FAIL, DEFER not used)
312 */
313
314 static int
315 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
316 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
317 {
318 smtp_transport_options_block *ob =
319 (smtp_transport_options_block *)(tblock->options_block);
320
321 errmsg = errmsg; /* Keep picky compilers happy */
322 uid = uid;
323 gid = gid;
324
325 /* Pass back options if required. This interface is getting very messy. */
326
327 if (tf != NULL)
328 {
329 tf->interface = ob->interface;
330 tf->port = ob->port;
331 tf->protocol = ob->protocol;
332 tf->hosts = ob->hosts;
333 tf->hosts_override = ob->hosts_override;
334 tf->hosts_randomize = ob->hosts_randomize;
335 tf->gethostbyname = ob->gethostbyname;
336 tf->qualify_single = ob->dns_qualify_single;
337 tf->search_parents = ob->dns_search_parents;
338 tf->helo_data = ob->helo_data;
339 }
340
341 /* Set the fallback host list for all the addresses that don't have fallback
342 host lists, provided that the local host wasn't present in the original host
343 list. */
344
345 if (!testflag(addrlist, af_local_host_removed))
346 {
347 for (; addrlist != NULL; addrlist = addrlist->next)
348 if (addrlist->fallback_hosts == NULL)
349 addrlist->fallback_hosts = ob->fallback_hostlist;
350 }
351
352 return OK;
353 }
354
355
356
357 /*************************************************
358 * Initialization entry point *
359 *************************************************/
360
361 /* Called for each instance, after its options have been read, to
362 enable consistency checks to be done, or anything else that needs
363 to be set up.
364
365 Argument: pointer to the transport instance block
366 Returns: nothing
367 */
368
369 void
370 smtp_transport_init(transport_instance *tblock)
371 {
372 smtp_transport_options_block *ob =
373 (smtp_transport_options_block *)(tblock->options_block);
374
375 /* Retry_use_local_part defaults FALSE if unset */
376
377 if (tblock->retry_use_local_part == TRUE_UNSET)
378 tblock->retry_use_local_part = FALSE;
379
380 /* Set the default port according to the protocol */
381
382 if (ob->port == NULL)
383 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
384 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
385
386 /* Set up the setup entry point, to be called before subprocesses for this
387 transport. */
388
389 tblock->setup = smtp_transport_setup;
390
391 /* Complain if any of the timeouts are zero. */
392
393 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
394 ob->final_timeout <= 0)
395 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
396 "command, data, or final timeout value is zero for %s transport",
397 tblock->name);
398
399 /* If hosts_override is set and there are local hosts, set the global
400 flag that stops verify from showing router hosts. */
401
402 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
403
404 /* If there are any fallback hosts listed, build a chain of host items
405 for them, but do not do any lookups at this time. */
406
407 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
408
409 #ifdef SUPPORT_TLS
410 if ( ob->gnutls_require_kx
411 || ob->gnutls_require_mac
412 || ob->gnutls_require_proto)
413 log_write(0, LOG_MAIN, "WARNING: smtp transport options"
414 " gnutls_require_kx, gnutls_require_mac and gnutls_require_protocols"
415 " are obsolete\n");
416 #endif
417 }
418
419
420
421
422
423 /*************************************************
424 * Set delivery info into all active addresses *
425 *************************************************/
426
427 /* Only addresses whose status is >= PENDING are relevant. A lesser
428 status means that an address is not currently being processed.
429
430 Arguments:
431 addrlist points to a chain of addresses
432 errno_value to put in each address's errno field
433 msg to put in each address's message field
434 rc to put in each address's transport_return field
435 pass_message if TRUE, set the "pass message" flag in the address
436 host if set, mark addrs as having used this host
437
438 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
439 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
440 this particular type of timeout.
441
442 Returns: nothing
443 */
444
445 static void
446 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
447 BOOL pass_message, host_item * host)
448 {
449 address_item *addr;
450 int orvalue = 0;
451 if (errno_value == ERRNO_CONNECTTIMEOUT)
452 {
453 errno_value = ETIMEDOUT;
454 orvalue = RTEF_CTOUT;
455 }
456 for (addr = addrlist; addr != NULL; addr = addr->next)
457 if (addr->transport_return >= PENDING)
458 {
459 addr->basic_errno = errno_value;
460 addr->more_errno |= orvalue;
461 if (msg != NULL)
462 {
463 addr->message = msg;
464 if (pass_message) setflag(addr, af_pass_message);
465 }
466 addr->transport_return = rc;
467 if (host)
468 addr->host_used = host;
469 }
470 }
471
472
473
474 /*************************************************
475 * Check an SMTP response *
476 *************************************************/
477
478 /* This function is given an errno code and the SMTP response buffer
479 to analyse, together with the host identification for generating messages. It
480 sets an appropriate message and puts the first digit of the response code into
481 the yield variable. If no response was actually read, a suitable digit is
482 chosen.
483
484 Arguments:
485 host the current host, to get its name for messages
486 errno_value pointer to the errno value
487 more_errno from the top address for use with ERRNO_FILTER_FAIL
488 buffer the SMTP response buffer
489 yield where to put a one-digit SMTP response code
490 message where to put an errror message
491 pass_message set TRUE if message is an SMTP response
492
493 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
494 */
495
496 static BOOL
497 check_response(host_item *host, int *errno_value, int more_errno,
498 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
499 {
500 uschar *pl = US"";
501
502 if (smtp_use_pipelining &&
503 (Ustrcmp(smtp_command, "MAIL") == 0 ||
504 Ustrcmp(smtp_command, "RCPT") == 0 ||
505 Ustrcmp(smtp_command, "DATA") == 0))
506 pl = US"pipelined ";
507
508 *yield = '4'; /* Default setting is to give a temporary error */
509
510 /* Handle response timeout */
511
512 if (*errno_value == ETIMEDOUT)
513 {
514 *message = US string_sprintf("SMTP timeout after %s%s",
515 pl, smtp_command);
516 if (transport_count > 0)
517 *message = US string_sprintf("%s (%d bytes written)", *message,
518 transport_count);
519 return FALSE;
520 }
521
522 /* Handle malformed SMTP response */
523
524 if (*errno_value == ERRNO_SMTPFORMAT)
525 {
526 uschar *malfresp = string_printing(buffer);
527 while (isspace(*malfresp)) malfresp++;
528 *message = *malfresp == 0
529 ? string_sprintf("Malformed SMTP reply (an empty line) "
530 "in response to %s%s", pl, smtp_command)
531 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
532 pl, smtp_command, malfresp);
533 return FALSE;
534 }
535
536 /* Handle a failed filter process error; can't send QUIT as we mustn't
537 end the DATA. */
538
539 if (*errno_value == ERRNO_FILTER_FAIL)
540 {
541 *message = US string_sprintf("transport filter process failed (%d)%s",
542 more_errno,
543 (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
544 return FALSE;
545 }
546
547 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
548 end the DATA. */
549
550 if (*errno_value == ERRNO_CHHEADER_FAIL)
551 {
552 *message =
553 US string_sprintf("failed to expand headers_add or headers_remove: %s",
554 expand_string_message);
555 return FALSE;
556 }
557
558 /* Handle failure to write a complete data block */
559
560 if (*errno_value == ERRNO_WRITEINCOMPLETE)
561 {
562 *message = US string_sprintf("failed to write a data block");
563 return FALSE;
564 }
565
566 /* Handle error responses from the remote mailer. */
567
568 if (buffer[0] != 0)
569 {
570 uschar *s = string_printing(buffer);
571 *message = US string_sprintf("SMTP error from remote mail server after %s%s: "
572 "%s", pl, smtp_command, s);
573 *pass_message = TRUE;
574 *yield = buffer[0];
575 return TRUE;
576 }
577
578 /* No data was read. If there is no errno, this must be the EOF (i.e.
579 connection closed) case, which causes deferral. An explicit connection reset
580 error has the same effect. Otherwise, put the host's identity in the message,
581 leaving the errno value to be interpreted as well. In all cases, we have to
582 assume the connection is now dead. */
583
584 if (*errno_value == 0 || *errno_value == ECONNRESET)
585 {
586 *errno_value = ERRNO_SMTPCLOSED;
587 *message = US string_sprintf("Remote host closed connection "
588 "in response to %s%s", pl, smtp_command);
589 }
590 else *message = US string_sprintf("%s [%s]", host->name, host->address);
591
592 return FALSE;
593 }
594
595
596
597 /*************************************************
598 * Write error message to logs *
599 *************************************************/
600
601 /* This writes to the main log and to the message log.
602
603 Arguments:
604 addr the address item containing error information
605 host the current host
606
607 Returns: nothing
608 */
609
610 static void
611 write_logs(address_item *addr, host_item *host)
612 {
613 uschar * message = string_sprintf("H=%s [%s]", host->name, host->address);
614
615 if (addr->message)
616 {
617 message = string_sprintf("%s: %s", message, addr->message);
618 if (addr->basic_errno > 0)
619 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
620 log_write(0, LOG_MAIN, "%s", message);
621 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
622 }
623 else
624 {
625 if (log_extra_selector & LX_outgoing_port)
626 message = string_sprintf("%s:%d", message,
627 host->port == PORT_NONE ? 25 : host->port);
628 log_write(0, LOG_MAIN, "%s %s", message, strerror(addr->basic_errno));
629 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), message,
630 strerror(addr->basic_errno));
631 }
632 }
633
634 static void
635 msglog_line(host_item * host, uschar * message)
636 {
637 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
638 host->name, host->address, message);
639 }
640
641
642
643 #ifdef EXPERIMENTAL_EVENT
644 /*************************************************
645 * Post-defer action *
646 *************************************************/
647
648 /* This expands an arbitrary per-transport string.
649 It might, for example, be used to write to the database log.
650
651 Arguments:
652 addr the address item containing error information
653 host the current host
654
655 Returns: nothing
656 */
657
658 static void
659 deferred_event_raise(address_item *addr, host_item *host)
660 {
661 uschar * action = addr->transport->event_action;
662 uschar * save_domain;
663 uschar * save_local;
664
665 if (!action)
666 return;
667
668 save_domain = deliver_domain;
669 save_local = deliver_localpart;
670
671 /*XXX would ip & port already be set up? */
672 deliver_host_address = string_copy(host->address);
673 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
674 event_defer_errno = addr->basic_errno;
675
676 router_name = addr->router->name;
677 transport_name = addr->transport->name;
678 deliver_domain = addr->domain;
679 deliver_localpart = addr->local_part;
680
681 (void) event_raise(action, US"msg:host:defer",
682 addr->message
683 ? addr->basic_errno > 0
684 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
685 : string_copy(addr->message)
686 : addr->basic_errno > 0
687 ? string_copy(US strerror(addr->basic_errno))
688 : NULL);
689
690 deliver_localpart = save_local;
691 deliver_domain = save_domain;
692 router_name = transport_name = NULL;
693 }
694 #endif
695
696
697
698 /*************************************************
699 * Synchronize SMTP responses *
700 *************************************************/
701
702 /* This function is called from smtp_deliver() to receive SMTP responses from
703 the server, and match them up with the commands to which they relate. When
704 PIPELINING is not in use, this function is called after every command, and is
705 therefore somewhat over-engineered, but it is simpler to use a single scheme
706 that works both with and without PIPELINING instead of having two separate sets
707 of code.
708
709 The set of commands that are buffered up with pipelining may start with MAIL
710 and may end with DATA; in between are RCPT commands that correspond to the
711 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
712 etc.) are never buffered.
713
714 Errors after MAIL or DATA abort the whole process leaving the response in the
715 buffer. After MAIL, pending responses are flushed, and the original command is
716 re-instated in big_buffer for error messages. For RCPT commands, the remote is
717 permitted to reject some recipient addresses while accepting others. However
718 certain errors clearly abort the whole process. Set the value in
719 transport_return to PENDING_OK if the address is accepted. If there is a
720 subsequent general error, it will get reset accordingly. If not, it will get
721 converted to OK at the end.
722
723 Arguments:
724 addrlist the complete address list
725 include_affixes TRUE if affixes include in RCPT
726 sync_addr ptr to the ptr of the one to start scanning at (updated)
727 host the host we are connected to
728 count the number of responses to read
729 address_retry_
730 include_sender true if 4xx retry is to include the sender it its key
731 pending_MAIL true if the first response is for MAIL
732 pending_DATA 0 if last command sent was not DATA
733 +1 if previously had a good recipient
734 -1 if not previously had a good recipient
735 inblock incoming SMTP block
736 timeout timeout value
737 buffer buffer for reading response
738 buffsize size of buffer
739
740 Returns: 3 if at least one address had 2xx and one had 5xx
741 2 if at least one address had 5xx but none had 2xx
742 1 if at least one host had a 2xx response, but none had 5xx
743 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
744 -1 timeout while reading RCPT response
745 -2 I/O or other non-response error for RCPT
746 -3 DATA or MAIL failed - errno and buffer set
747 */
748
749 static int
750 sync_responses(address_item *addrlist, BOOL include_affixes,
751 address_item **sync_addr, host_item *host, int count,
752 BOOL address_retry_include_sender, BOOL pending_MAIL,
753 int pending_DATA, smtp_inblock *inblock, int timeout, uschar *buffer,
754 int buffsize)
755 {
756 address_item *addr = *sync_addr;
757 int yield = 0;
758
759 /* Handle the response for a MAIL command. On error, reinstate the original
760 command in big_buffer for error message use, and flush any further pending
761 responses before returning, except after I/O errors and timeouts. */
762
763 if (pending_MAIL)
764 {
765 count--;
766 if (!smtp_read_response(inblock, buffer, buffsize, '2', timeout))
767 {
768 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
769 if (errno == 0 && buffer[0] != 0)
770 {
771 uschar flushbuffer[4096];
772 int save_errno = 0;
773 if (buffer[0] == '4')
774 {
775 save_errno = ERRNO_MAIL4XX;
776 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
777 }
778 while (count-- > 0)
779 {
780 if (!smtp_read_response(inblock, flushbuffer, sizeof(flushbuffer),
781 '2', timeout)
782 && (errno != 0 || flushbuffer[0] == 0))
783 break;
784 }
785 errno = save_errno;
786 }
787
788 if (pending_DATA) count--; /* Number of RCPT responses to come */
789 while (count-- > 0) /* Mark any pending addrs with the host used */
790 {
791 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
792 addr->host_used = host;
793 addr = addr->next;
794 }
795 return -3;
796 }
797 }
798
799 if (pending_DATA) count--; /* Number of RCPT responses to come */
800
801 /* Read and handle the required number of RCPT responses, matching each one up
802 with an address by scanning for the next address whose status is PENDING_DEFER.
803 */
804
805 while (count-- > 0)
806 {
807 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
808
809 /* The address was accepted */
810 addr->host_used = host;
811
812 if (smtp_read_response(inblock, buffer, buffsize, '2', timeout))
813 {
814 yield |= 1;
815 addr->transport_return = PENDING_OK;
816
817 /* If af_dr_retry_exists is set, there was a routing delay on this address;
818 ensure that any address-specific retry record is expunged. We do this both
819 for the basic key and for the version that also includes the sender. */
820
821 if (testflag(addr, af_dr_retry_exists))
822 {
823 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
824 sender_address);
825 retry_add_item(addr, altkey, rf_delete);
826 retry_add_item(addr, addr->address_retry_key, rf_delete);
827 }
828 }
829
830 /* Timeout while reading the response */
831
832 else if (errno == ETIMEDOUT)
833 {
834 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
835 transport_rcpt_address(addr, include_affixes));
836 set_errno(addrlist, ETIMEDOUT, message, DEFER, FALSE, NULL);
837 retry_add_item(addr, addr->address_retry_key, 0);
838 update_waiting = FALSE;
839 return -1;
840 }
841
842 /* Handle other errors in obtaining an SMTP response by returning -1. This
843 will cause all the addresses to be deferred. Restore the SMTP command in
844 big_buffer for which we are checking the response, so the error message
845 makes sense. */
846
847 else if (errno != 0 || buffer[0] == 0)
848 {
849 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
850 transport_rcpt_address(addr, include_affixes));
851 return -2;
852 }
853
854 /* Handle SMTP permanent and temporary response codes. */
855
856 else
857 {
858 addr->message =
859 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
860 "%s", transport_rcpt_address(addr, include_affixes),
861 string_printing(buffer));
862 setflag(addr, af_pass_message);
863 msglog_line(host, addr->message);
864
865 /* The response was 5xx */
866
867 if (buffer[0] == '5')
868 {
869 addr->transport_return = FAIL;
870 yield |= 2;
871 }
872
873 /* The response was 4xx */
874
875 else
876 {
877 addr->transport_return = DEFER;
878 addr->basic_errno = ERRNO_RCPT4XX;
879 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
880
881 /* Log temporary errors if there are more hosts to be tried.
882 If not, log this last one in the == line. */
883
884 if (host->next)
885 log_write(0, LOG_MAIN, "H=%s [%s]: %s", host->name, host->address, addr->message);
886
887 /* Do not put this message on the list of those waiting for specific
888 hosts, as otherwise it is likely to be tried too often. */
889
890 update_waiting = FALSE;
891
892 /* Add a retry item for the address so that it doesn't get tried again
893 too soon. If address_retry_include_sender is true, add the sender address
894 to the retry key. */
895
896 if (address_retry_include_sender)
897 {
898 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
899 sender_address);
900 retry_add_item(addr, altkey, 0);
901 }
902 else retry_add_item(addr, addr->address_retry_key, 0);
903 }
904 }
905 } /* Loop for next RCPT response */
906
907 /* Update where to start at for the next block of responses, unless we
908 have already handled all the addresses. */
909
910 if (addr != NULL) *sync_addr = addr->next;
911
912 /* Handle a response to DATA. If we have not had any good recipients, either
913 previously or in this block, the response is ignored. */
914
915 if (pending_DATA != 0 &&
916 !smtp_read_response(inblock, buffer, buffsize, '3', timeout))
917 {
918 int code;
919 uschar *msg;
920 BOOL pass_message;
921 if (pending_DATA > 0 || (yield & 1) != 0)
922 {
923 if (errno == 0 && buffer[0] == '4')
924 {
925 errno = ERRNO_DATA4XX;
926 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
927 }
928 return -3;
929 }
930 (void)check_response(host, &errno, 0, buffer, &code, &msg, &pass_message);
931 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
932 "is in use and there were no good recipients\n", msg);
933 }
934
935 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
936 present) received 3xx. If any RCPTs were handled and yielded anything other
937 than 4xx, yield will be set non-zero. */
938
939 return yield;
940 }
941
942
943
944 /* Do the client side of smtp-level authentication */
945 /*
946 Arguments:
947 buffer EHLO response from server (gets overwritten)
948 addrlist chain of potential addresses to deliver
949 host host to deliver to
950 ob transport options
951 ibp, obp comms channel control blocks
952
953 Returns:
954 OK Success, or failed (but not required): global "smtp_authenticated" set
955 DEFER Failed authentication (and was required)
956 ERROR Internal problem
957
958 FAIL_SEND Failed communications - transmit
959 FAIL - response
960 */
961
962 int
963 smtp_auth(uschar *buffer, unsigned bufsize, address_item *addrlist, host_item *host,
964 smtp_transport_options_block *ob, BOOL is_esmtp,
965 smtp_inblock *ibp, smtp_outblock *obp)
966 {
967 int require_auth;
968 uschar *fail_reason = US"server did not advertise AUTH support";
969
970 smtp_authenticated = FALSE;
971 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
972 require_auth = verify_check_given_host(&ob->hosts_require_auth, host);
973
974 if (is_esmtp && !regex_AUTH) regex_AUTH =
975 regex_must_compile(US"\\n250[\\s\\-]AUTH\\s+([\\-\\w\\s]+)(?:\\n|$)",
976 FALSE, TRUE);
977
978 if (is_esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
979 {
980 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
981 expand_nmax = -1; /* reset */
982
983 /* Must not do this check until after we have saved the result of the
984 regex match above. */
985
986 if (require_auth == OK ||
987 verify_check_given_host(&ob->hosts_try_auth, host) == OK)
988 {
989 auth_instance *au;
990 fail_reason = US"no common mechanisms were found";
991
992 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
993
994 /* Scan the configured authenticators looking for one which is configured
995 for use as a client, which is not suppressed by client_condition, and
996 whose name matches an authentication mechanism supported by the server.
997 If one is found, attempt to authenticate by calling its client function.
998 */
999
1000 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1001 {
1002 uschar *p = names;
1003 if (!au->client ||
1004 (au->client_condition != NULL &&
1005 !expand_check_condition(au->client_condition, au->name,
1006 US"client authenticator")))
1007 {
1008 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1009 au->name,
1010 (au->client)? "client_condition is false" :
1011 "not configured as a client");
1012 continue;
1013 }
1014
1015 /* Loop to scan supported server mechanisms */
1016
1017 while (*p != 0)
1018 {
1019 int rc;
1020 int len = Ustrlen(au->public_name);
1021 while (isspace(*p)) p++;
1022
1023 if (strncmpic(au->public_name, p, len) != 0 ||
1024 (p[len] != 0 && !isspace(p[len])))
1025 {
1026 while (*p != 0 && !isspace(*p)) p++;
1027 continue;
1028 }
1029
1030 /* Found data for a listed mechanism. Call its client entry. Set
1031 a flag in the outblock so that data is overwritten after sending so
1032 that reflections don't show it. */
1033
1034 fail_reason = US"authentication attempt(s) failed";
1035 obp->authenticating = TRUE;
1036 rc = (au->info->clientcode)(au, ibp, obp,
1037 ob->command_timeout, buffer, bufsize);
1038 obp->authenticating = FALSE;
1039 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1040 au->name, rc);
1041
1042 /* A temporary authentication failure must hold up delivery to
1043 this host. After a permanent authentication failure, we carry on
1044 to try other authentication methods. If all fail hard, try to
1045 deliver the message unauthenticated unless require_auth was set. */
1046
1047 switch(rc)
1048 {
1049 case OK:
1050 smtp_authenticated = TRUE; /* stops the outer loop */
1051 client_authenticator = au->name;
1052 if (au->set_client_id != NULL)
1053 client_authenticated_id = expand_string(au->set_client_id);
1054 break;
1055
1056 /* Failure after writing a command */
1057
1058 case FAIL_SEND:
1059 return FAIL_SEND;
1060
1061 /* Failure after reading a response */
1062
1063 case FAIL:
1064 if (errno != 0 || buffer[0] != '5') return FAIL;
1065 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1066 au->name, host->name, host->address, buffer);
1067 break;
1068
1069 /* Failure by some other means. In effect, the authenticator
1070 decided it wasn't prepared to handle this case. Typically this
1071 is the result of "fail" in an expansion string. Do we need to
1072 log anything here? Feb 2006: a message is now put in the buffer
1073 if logging is required. */
1074
1075 case CANCELLED:
1076 if (*buffer != 0)
1077 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1078 "authentication H=%s [%s] %s", au->name, host->name,
1079 host->address, buffer);
1080 break;
1081
1082 /* Internal problem, message in buffer. */
1083
1084 case ERROR:
1085 set_errno(addrlist, ERRNO_AUTHPROB, string_copy(buffer),
1086 DEFER, FALSE, NULL);
1087 return ERROR;
1088 }
1089
1090 break; /* If not authenticated, try next authenticator */
1091 } /* Loop for scanning supported server mechanisms */
1092 } /* Loop for further authenticators */
1093 }
1094 }
1095
1096 /* If we haven't authenticated, but are required to, give up. */
1097
1098 if (require_auth == OK && !smtp_authenticated)
1099 {
1100 set_errno(addrlist, ERRNO_AUTHFAIL,
1101 string_sprintf("authentication required but %s", fail_reason), DEFER,
1102 FALSE, NULL);
1103 return DEFER;
1104 }
1105
1106 return OK;
1107 }
1108
1109
1110 /* Construct AUTH appendix string for MAIL TO */
1111 /*
1112 Arguments
1113 buffer to build string
1114 addrlist chain of potential addresses to deliver
1115 ob transport options
1116
1117 Globals smtp_authenticated
1118 client_authenticated_sender
1119 Return True on error, otherwise buffer has (possibly empty) terminated string
1120 */
1121
1122 BOOL
1123 smtp_mail_auth_str(uschar *buffer, unsigned bufsize, address_item *addrlist,
1124 smtp_transport_options_block *ob)
1125 {
1126 uschar *local_authenticated_sender = authenticated_sender;
1127
1128 #ifdef notdef
1129 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n", authenticated_sender, ob->authenticated_sender, smtp_authenticated?"Y":"N");
1130 #endif
1131
1132 if (ob->authenticated_sender != NULL)
1133 {
1134 uschar *new = expand_string(ob->authenticated_sender);
1135 if (new == NULL)
1136 {
1137 if (!expand_string_forcedfail)
1138 {
1139 uschar *message = string_sprintf("failed to expand "
1140 "authenticated_sender: %s", expand_string_message);
1141 set_errno(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, NULL);
1142 return TRUE;
1143 }
1144 }
1145 else if (new[0] != 0) local_authenticated_sender = new;
1146 }
1147
1148 /* Add the authenticated sender address if present */
1149
1150 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1151 local_authenticated_sender != NULL)
1152 {
1153 string_format(buffer, bufsize, " AUTH=%s",
1154 auth_xtextencode(local_authenticated_sender,
1155 Ustrlen(local_authenticated_sender)));
1156 client_authenticated_sender = string_copy(local_authenticated_sender);
1157 }
1158 else
1159 *buffer= 0;
1160
1161 return FALSE;
1162 }
1163
1164
1165
1166 #ifdef EXPERIMENTAL_DANE
1167 int
1168 tlsa_lookup(host_item * host, dns_answer * dnsa,
1169 BOOL dane_required, BOOL * dane)
1170 {
1171 /* move this out to host.c given the similarity to dns_lookup() ? */
1172 uschar buffer[300];
1173 uschar * fullname = buffer;
1174
1175 /* TLSA lookup string */
1176 (void)sprintf(CS buffer, "_%d._tcp.%.256s", host->port, host->name);
1177
1178 switch (dns_lookup(dnsa, buffer, T_TLSA, &fullname))
1179 {
1180 case DNS_AGAIN:
1181 return DEFER; /* just defer this TLS'd conn */
1182
1183 default:
1184 case DNS_FAIL:
1185 if (dane_required)
1186 {
1187 log_write(0, LOG_MAIN, "DANE error: TLSA lookup failed");
1188 return FAIL;
1189 }
1190 break;
1191
1192 case DNS_SUCCEED:
1193 if (!dns_is_secure(dnsa))
1194 {
1195 log_write(0, LOG_MAIN, "DANE error: TLSA lookup not DNSSEC");
1196 return DEFER;
1197 }
1198 *dane = TRUE;
1199 break;
1200 }
1201 return OK;
1202 }
1203 #endif
1204
1205
1206 /*************************************************
1207 * Deliver address list to given host *
1208 *************************************************/
1209
1210 /* If continue_hostname is not null, we get here only when continuing to
1211 deliver down an existing channel. The channel was passed as the standard
1212 input. TLS is never active on a passed channel; the previous process always
1213 closes it down before passing the connection on.
1214
1215 Otherwise, we have to make a connection to the remote host, and do the
1216 initial protocol exchange.
1217
1218 When running as an MUA wrapper, if the sender or any recipient is rejected,
1219 temporarily or permanently, we force failure for all recipients.
1220
1221 Arguments:
1222 addrlist chain of potential addresses to deliver; only those whose
1223 transport_return field is set to PENDING_DEFER are currently
1224 being processed; others should be skipped - they have either
1225 been delivered to an earlier host or IP address, or been
1226 failed by one of them.
1227 host host to deliver to
1228 host_af AF_INET or AF_INET6
1229 port default TCP/IP port to use, in host byte order
1230 interface interface to bind to, or NULL
1231 tblock transport instance block
1232 copy_host TRUE if host set in addr->host_used must be copied, because
1233 it is specific to this call of the transport
1234 message_defer set TRUE if yield is OK, but all addresses were deferred
1235 because of a non-recipient, non-host failure, that is, a
1236 4xx response to MAIL FROM, DATA, or ".". This is a defer
1237 that is specific to the message.
1238 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1239 a second attempt after TLS initialization fails
1240
1241 Returns: OK - the connection was made and the delivery attempted;
1242 the result for each address is in its data block.
1243 DEFER - the connection could not be made, or something failed
1244 while setting up the SMTP session, or there was a
1245 non-message-specific error, such as a timeout.
1246 ERROR - a filter command is specified for this transport,
1247 and there was a problem setting it up; OR helo_data
1248 or add_headers or authenticated_sender is specified
1249 for this transport, and the string failed to expand
1250 */
1251
1252 static int
1253 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int port,
1254 uschar *interface, transport_instance *tblock, BOOL copy_host,
1255 BOOL *message_defer, BOOL suppress_tls)
1256 {
1257 address_item *addr;
1258 address_item *sync_addr;
1259 address_item *first_addr = addrlist;
1260 int yield = OK;
1261 int address_count;
1262 int save_errno;
1263 int rc;
1264 time_t start_delivery_time = time(NULL);
1265 smtp_transport_options_block *ob =
1266 (smtp_transport_options_block *)(tblock->options_block);
1267 BOOL lmtp = strcmpic(ob->protocol, US"lmtp") == 0;
1268 BOOL smtps = strcmpic(ob->protocol, US"smtps") == 0;
1269 BOOL ok = FALSE;
1270 BOOL send_rset = TRUE;
1271 BOOL send_quit = TRUE;
1272 BOOL setting_up = TRUE;
1273 BOOL completed_address = FALSE;
1274 BOOL esmtp = TRUE;
1275 BOOL pending_MAIL;
1276 BOOL pass_message = FALSE;
1277 #ifndef DISABLE_PRDR
1278 BOOL prdr_offered = FALSE;
1279 BOOL prdr_active;
1280 #endif
1281 BOOL dsn_all_lasthop = TRUE;
1282 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1283 BOOL dane = FALSE;
1284 dns_answer tlsa_dnsa;
1285 #endif
1286 smtp_inblock inblock;
1287 smtp_outblock outblock;
1288 int max_rcpt = tblock->max_addresses;
1289 uschar *igquotstr = US"";
1290 uschar *helo_data = NULL;
1291 uschar *message = NULL;
1292 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
1293 uschar *p;
1294 uschar buffer[4096];
1295 uschar inbuffer[4096];
1296 uschar outbuffer[4096];
1297
1298 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
1299
1300 *message_defer = FALSE;
1301 smtp_command = US"initial connection";
1302 if (max_rcpt == 0) max_rcpt = 999999;
1303
1304 /* Set up the buffer for reading SMTP response packets. */
1305
1306 inblock.buffer = inbuffer;
1307 inblock.buffersize = sizeof(inbuffer);
1308 inblock.ptr = inbuffer;
1309 inblock.ptrend = inbuffer;
1310
1311 /* Set up the buffer for holding SMTP commands while pipelining */
1312
1313 outblock.buffer = outbuffer;
1314 outblock.buffersize = sizeof(outbuffer);
1315 outblock.ptr = outbuffer;
1316 outblock.cmd_count = 0;
1317 outblock.authenticating = FALSE;
1318
1319 /* Reset the parameters of a TLS session. */
1320
1321 tls_out.bits = 0;
1322 tls_out.cipher = NULL; /* the one we may use for this transport */
1323 tls_out.ourcert = NULL;
1324 tls_out.peercert = NULL;
1325 tls_out.peerdn = NULL;
1326 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1327 tls_out.sni = NULL;
1328 #endif
1329 tls_out.ocsp = OCSP_NOT_REQ;
1330
1331 /* Flip the legacy TLS-related variables over to the outbound set in case
1332 they're used in the context of the transport. Don't bother resetting
1333 afterward as we're in a subprocess. */
1334
1335 tls_modify_variables(&tls_out);
1336
1337 #ifndef SUPPORT_TLS
1338 if (smtps)
1339 {
1340 set_errno(addrlist, ERRNO_TLSFAILURE, US"TLS support not available",
1341 DEFER, FALSE, NULL);
1342 return ERROR;
1343 }
1344 #endif
1345
1346 /* Make a connection to the host if this isn't a continued delivery, and handle
1347 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
1348 specially so they can be identified for retries. */
1349
1350 if (continue_hostname == NULL)
1351 {
1352 /* This puts port into host->port */
1353 inblock.sock = outblock.sock =
1354 smtp_connect(host, host_af, port, interface, ob->connect_timeout,
1355 ob->keepalive, ob->dscp
1356 #ifdef EXPERIMENTAL_EVENT
1357 , tblock->event_action
1358 #endif
1359 );
1360
1361 if (inblock.sock < 0)
1362 {
1363 set_errno(addrlist, (errno == ETIMEDOUT)? ERRNO_CONNECTTIMEOUT : errno,
1364 NULL, DEFER, FALSE, NULL);
1365 return DEFER;
1366 }
1367
1368 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1369 {
1370 BOOL dane_required;
1371
1372 tls_out.dane_verified = FALSE;
1373 tls_out.tlsa_usage = 0;
1374
1375 dane_required = verify_check_given_host(&ob->hosts_require_dane, host) == OK;
1376
1377 if (host->dnssec == DS_YES)
1378 {
1379 if( dane_required
1380 || verify_check_given_host(&ob->hosts_try_dane, host) == OK
1381 )
1382 if ((rc = tlsa_lookup(host, &tlsa_dnsa, dane_required, &dane)) != OK)
1383 return rc;
1384 }
1385 else if (dane_required)
1386 {
1387 log_write(0, LOG_MAIN, "DANE error: %s lookup not DNSSEC", host->name);
1388 return FAIL;
1389 }
1390
1391 if (dane)
1392 ob->tls_tempfail_tryclear = FALSE;
1393 }
1394 #endif /*DANE*/
1395
1396 /* Expand the greeting message while waiting for the initial response. (Makes
1397 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1398 delayed till here so that $sending_interface and $sending_port are set. */
1399
1400 helo_data = expand_string(ob->helo_data);
1401
1402 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1403 is nevertheless a reasonably clean way of programming this kind of logic,
1404 where you want to escape on any error. */
1405
1406 if (!smtps)
1407 {
1408 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1409 ob->command_timeout)) goto RESPONSE_FAILED;
1410
1411 #ifdef EXPERIMENTAL_EVENT
1412 {
1413 uschar * s;
1414 lookup_dnssec_authenticated = host->dnssec==DS_YES ? US"yes"
1415 : host->dnssec==DS_NO ? US"no" : NULL;
1416 s = event_raise(tblock->event_action, US"smtp:connect", buffer);
1417 if (s)
1418 {
1419 set_errno(addrlist, ERRNO_EXPANDFAIL,
1420 string_sprintf("deferred by smtp:connect event expansion: %s", s),
1421 DEFER, FALSE, NULL);
1422 yield = DEFER;
1423 goto SEND_QUIT;
1424 }
1425 }
1426 #endif
1427
1428 /* Now check if the helo_data expansion went well, and sign off cleanly if
1429 it didn't. */
1430
1431 if (helo_data == NULL)
1432 {
1433 uschar *message = string_sprintf("failed to expand helo_data: %s",
1434 expand_string_message);
1435 set_errno(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, NULL);
1436 yield = DEFER;
1437 goto SEND_QUIT;
1438 }
1439 }
1440
1441 /** Debugging without sending a message
1442 addrlist->transport_return = DEFER;
1443 goto SEND_QUIT;
1444 **/
1445
1446 /* Errors that occur after this point follow an SMTP command, which is
1447 left in big_buffer by smtp_write_command() for use in error messages. */
1448
1449 smtp_command = big_buffer;
1450
1451 /* Tell the remote who we are...
1452
1453 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1454 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1455 greeting is of this form. The assumption was that the far end supports it
1456 properly... but experience shows that there are some that give 5xx responses,
1457 even though the banner includes "ESMTP" (there's a bloody-minded one that
1458 says "ESMTP not spoken here"). Cope with that case.
1459
1460 September 2000: Time has passed, and it seems reasonable now to always send
1461 EHLO at the start. It is also convenient to make the change while installing
1462 the TLS stuff.
1463
1464 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1465 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1466 would be no way to send out the mails, so there is now a host list
1467 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1468 PIPELINING problem as well. Maybe it can also be useful to cure other
1469 problems with broken servers.
1470
1471 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1472 Then somebody tried it with a Microsoft mailer... It seems that all other
1473 mailers use upper case for some reason (the RFC is quite clear about case
1474 independence) so, for peace of mind, I gave in. */
1475
1476 esmtp = verify_check_given_host(&ob->hosts_avoid_esmtp, host) != OK;
1477
1478 /* Alas; be careful, since this goto is not an error-out, so conceivably
1479 we might set data between here and the target which we assume to exist
1480 and be usable. I can see this coming back to bite us. */
1481 #ifdef SUPPORT_TLS
1482 if (smtps)
1483 {
1484 tls_offered = TRUE;
1485 suppress_tls = FALSE;
1486 ob->tls_tempfail_tryclear = FALSE;
1487 smtp_command = US"SSL-on-connect";
1488 goto TLS_NEGOTIATE;
1489 }
1490 #endif
1491
1492 if (esmtp)
1493 {
1494 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1495 lmtp? "LHLO" : "EHLO", helo_data) < 0)
1496 goto SEND_FAILED;
1497 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1498 ob->command_timeout))
1499 {
1500 if (errno != 0 || buffer[0] == 0 || lmtp) goto RESPONSE_FAILED;
1501 esmtp = FALSE;
1502 }
1503 }
1504 else
1505 {
1506 DEBUG(D_transport)
1507 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1508 }
1509
1510 if (!esmtp)
1511 {
1512 if (smtp_write_command(&outblock, FALSE, "HELO %s\r\n", helo_data) < 0)
1513 goto SEND_FAILED;
1514 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1515 ob->command_timeout)) goto RESPONSE_FAILED;
1516 }
1517
1518 /* Set IGNOREQUOTA if the response to LHLO specifies support and the
1519 lmtp_ignore_quota option was set. */
1520
1521 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1522 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1523 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1524
1525 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1526
1527 #ifdef SUPPORT_TLS
1528 tls_offered = esmtp &&
1529 pcre_exec(regex_STARTTLS, NULL, CS buffer, Ustrlen(buffer), 0,
1530 PCRE_EOPT, NULL, 0) >= 0;
1531 #endif
1532
1533 #ifndef DISABLE_PRDR
1534 prdr_offered = esmtp
1535 && pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(buffer), 0,
1536 PCRE_EOPT, NULL, 0) >= 0
1537 && verify_check_given_host(&ob->hosts_try_prdr, host) == OK;
1538
1539 if (prdr_offered)
1540 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1541 #endif
1542 }
1543
1544 /* For continuing deliveries down the same channel, the socket is the standard
1545 input, and we don't need to redo EHLO here (but may need to do so for TLS - see
1546 below). Set up the pointer to where subsequent commands will be left, for
1547 error messages. Note that smtp_use_size and smtp_use_pipelining will have been
1548 set from the command line if they were set in the process that passed the
1549 connection on. */
1550
1551 else
1552 {
1553 inblock.sock = outblock.sock = fileno(stdin);
1554 smtp_command = big_buffer;
1555 host->port = port; /* Record the port that was used */
1556 }
1557
1558 /* If TLS is available on this connection, whether continued or not, attempt to
1559 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1560 send another EHLO - the server may give a different answer in secure mode. We
1561 use a separate buffer for reading the response to STARTTLS so that if it is
1562 negative, the original EHLO data is available for subsequent analysis, should
1563 the client not be required to use TLS. If the response is bad, copy the buffer
1564 for error analysis. */
1565
1566 #ifdef SUPPORT_TLS
1567 if ( tls_offered
1568 && !suppress_tls
1569 && verify_check_given_host(&ob->hosts_avoid_tls, host) != OK)
1570 {
1571 uschar buffer2[4096];
1572 if (smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") < 0)
1573 goto SEND_FAILED;
1574
1575 /* If there is an I/O error, transmission of this message is deferred. If
1576 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1577 false, we also defer. However, if there is a temporary rejection of STARTTLS
1578 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1579 STARTTLS, we carry on. This means we will try to send the message in clear,
1580 unless the host is in hosts_require_tls (tested below). */
1581
1582 if (!smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2',
1583 ob->command_timeout))
1584 {
1585 if (errno != 0 || buffer2[0] == 0 ||
1586 (buffer2[0] == '4' && !ob->tls_tempfail_tryclear))
1587 {
1588 Ustrncpy(buffer, buffer2, sizeof(buffer));
1589 goto RESPONSE_FAILED;
1590 }
1591 }
1592
1593 /* STARTTLS accepted: try to negotiate a TLS session. */
1594
1595 else
1596 TLS_NEGOTIATE:
1597 {
1598 int rc = tls_client_start(inblock.sock, host, addrlist, tblock
1599 # ifdef EXPERIMENTAL_DANE
1600 , dane ? &tlsa_dnsa : NULL
1601 # endif
1602 );
1603
1604 /* TLS negotiation failed; give an error. From outside, this function may
1605 be called again to try in clear on a new connection, if the options permit
1606 it for this host. */
1607
1608 if (rc != OK)
1609 {
1610 save_errno = ERRNO_TLSFAILURE;
1611 message = US"failure while setting up TLS session";
1612 send_quit = FALSE;
1613 goto TLS_FAILED;
1614 }
1615
1616 /* TLS session is set up */
1617
1618 for (addr = addrlist; addr != NULL; addr = addr->next)
1619 if (addr->transport_return == PENDING_DEFER)
1620 {
1621 addr->cipher = tls_out.cipher;
1622 addr->ourcert = tls_out.ourcert;
1623 addr->peercert = tls_out.peercert;
1624 addr->peerdn = tls_out.peerdn;
1625 addr->ocsp = tls_out.ocsp;
1626 }
1627 }
1628 }
1629
1630 /* if smtps, we'll have smtp_command set to something else; always safe to
1631 reset it here. */
1632 smtp_command = big_buffer;
1633
1634 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1635 helo_data is null, we are dealing with a connection that was passed from
1636 another process, and so we won't have expanded helo_data above. We have to
1637 expand it here. $sending_ip_address and $sending_port are set up right at the
1638 start of the Exim process (in exim.c). */
1639
1640 if (tls_out.active >= 0)
1641 {
1642 char *greeting_cmd;
1643 if (helo_data == NULL)
1644 {
1645 helo_data = expand_string(ob->helo_data);
1646 if (helo_data == NULL)
1647 {
1648 uschar *message = string_sprintf("failed to expand helo_data: %s",
1649 expand_string_message);
1650 set_errno(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE, NULL);
1651 yield = DEFER;
1652 goto SEND_QUIT;
1653 }
1654 }
1655
1656 /* For SMTPS we need to wait for the initial OK response. */
1657 if (smtps)
1658 {
1659 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1660 ob->command_timeout)) goto RESPONSE_FAILED;
1661 }
1662
1663 if (esmtp)
1664 greeting_cmd = "EHLO";
1665 else
1666 {
1667 greeting_cmd = "HELO";
1668 DEBUG(D_transport)
1669 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1670 }
1671
1672 if (smtp_write_command(&outblock, FALSE, "%s %s\r\n",
1673 lmtp? "LHLO" : greeting_cmd, helo_data) < 0)
1674 goto SEND_FAILED;
1675 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1676 ob->command_timeout))
1677 goto RESPONSE_FAILED;
1678 }
1679
1680 /* If the host is required to use a secure channel, ensure that we
1681 have one. */
1682
1683 else if (
1684 # ifdef EXPERIMENTAL_DANE
1685 dane ||
1686 # endif
1687 verify_check_given_host(&ob->hosts_require_tls, host) == OK
1688 )
1689 {
1690 save_errno = ERRNO_TLSREQUIRED;
1691 message = string_sprintf("a TLS session is required, but %s",
1692 tls_offered? "an attempt to start TLS failed" :
1693 "the server did not offer TLS support");
1694 goto TLS_FAILED;
1695 }
1696 #endif /*SUPPORT_TLS*/
1697
1698 /* If TLS is active, we have just started it up and re-done the EHLO command,
1699 so its response needs to be analyzed. If TLS is not active and this is a
1700 continued session down a previously-used socket, we haven't just done EHLO, so
1701 we skip this. */
1702
1703 if (continue_hostname == NULL
1704 #ifdef SUPPORT_TLS
1705 || tls_out.active >= 0
1706 #endif
1707 )
1708 {
1709 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
1710 lmtp_ignore_quota option was set. */
1711
1712 igquotstr = (lmtp && ob->lmtp_ignore_quota &&
1713 pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer, Ustrlen(CS buffer), 0,
1714 PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
1715
1716 /* If the response to EHLO specified support for the SIZE parameter, note
1717 this, provided size_addition is non-negative. */
1718
1719 smtp_use_size = esmtp && ob->size_addition >= 0 &&
1720 pcre_exec(regex_SIZE, NULL, CS buffer, Ustrlen(CS buffer), 0,
1721 PCRE_EOPT, NULL, 0) >= 0;
1722
1723 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
1724 the current host, esmtp will be false, so PIPELINING can never be used. If
1725 the current host matches hosts_avoid_pipelining, don't do it. */
1726
1727 smtp_use_pipelining = esmtp
1728 && verify_check_given_host(&ob->hosts_avoid_pipelining, host) != OK
1729 && pcre_exec(regex_PIPELINING, NULL, CS buffer, Ustrlen(CS buffer), 0,
1730 PCRE_EOPT, NULL, 0) >= 0;
1731
1732 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
1733 smtp_use_pipelining? "" : "not ");
1734
1735 #ifndef DISABLE_PRDR
1736 prdr_offered = esmtp
1737 && pcre_exec(regex_PRDR, NULL, CS buffer, Ustrlen(CS buffer), 0,
1738 PCRE_EOPT, NULL, 0) >= 0
1739 && verify_check_given_host(&ob->hosts_try_prdr, host) == OK;
1740
1741 if (prdr_offered)
1742 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
1743 #endif
1744
1745 /* Note if the server supports DSN */
1746 smtp_use_dsn = esmtp && pcre_exec(regex_DSN, NULL, CS buffer, (int)Ustrlen(CS buffer), 0,
1747 PCRE_EOPT, NULL, 0) >= 0;
1748 DEBUG(D_transport) debug_printf("use_dsn=%d\n", smtp_use_dsn);
1749
1750 /* Note if the response to EHLO specifies support for the AUTH extension.
1751 If it has, check that this host is one we want to authenticate to, and do
1752 the business. The host name and address must be available when the
1753 authenticator's client driver is running. */
1754
1755 switch (yield = smtp_auth(buffer, sizeof(buffer), addrlist, host,
1756 ob, esmtp, &inblock, &outblock))
1757 {
1758 default: goto SEND_QUIT;
1759 case OK: break;
1760 case FAIL_SEND: goto SEND_FAILED;
1761 case FAIL: goto RESPONSE_FAILED;
1762 }
1763 }
1764
1765 /* The setting up of the SMTP call is now complete. Any subsequent errors are
1766 message-specific. */
1767
1768 setting_up = FALSE;
1769
1770 /* If there is a filter command specified for this transport, we can now
1771 set it up. This cannot be done until the identify of the host is known. */
1772
1773 if (tblock->filter_command != NULL)
1774 {
1775 BOOL rc;
1776 uschar buffer[64];
1777 sprintf(CS buffer, "%.50s transport", tblock->name);
1778 rc = transport_set_up_command(&transport_filter_argv, tblock->filter_command,
1779 TRUE, DEFER, addrlist, buffer, NULL);
1780 transport_filter_timeout = tblock->filter_timeout;
1781
1782 /* On failure, copy the error to all addresses, abandon the SMTP call, and
1783 yield ERROR. */
1784
1785 if (!rc)
1786 {
1787 set_errno(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
1788 FALSE, NULL);
1789 yield = ERROR;
1790 goto SEND_QUIT;
1791 }
1792 }
1793
1794
1795 /* For messages that have more than the maximum number of envelope recipients,
1796 we want to send several transactions down the same SMTP connection. (See
1797 comments in deliver.c as to how this reconciles, heuristically, with
1798 remote_max_parallel.) This optimization was added to Exim after the following
1799 code was already working. The simplest way to put it in without disturbing the
1800 code was to use a goto to jump back to this point when there is another
1801 transaction to handle. */
1802
1803 SEND_MESSAGE:
1804 sync_addr = first_addr;
1805 address_count = 0;
1806 ok = FALSE;
1807 send_rset = TRUE;
1808 completed_address = FALSE;
1809
1810
1811 /* Initiate a message transfer. If we know the receiving MTA supports the SIZE
1812 qualification, send it, adding something to the message size to allow for
1813 imprecision and things that get added en route. Exim keeps the number of lines
1814 in a message, so we can give an accurate value for the original message, but we
1815 need some additional to handle added headers. (Double "." characters don't get
1816 included in the count.) */
1817
1818 p = buffer;
1819 *p = 0;
1820
1821 if (smtp_use_size)
1822 {
1823 sprintf(CS p, " SIZE=%d", message_size+message_linecount+ob->size_addition);
1824 while (*p) p++;
1825 }
1826
1827 #ifndef DISABLE_PRDR
1828 prdr_active = FALSE;
1829 if (prdr_offered)
1830 {
1831 for (addr = first_addr; addr; addr = addr->next)
1832 if (addr->transport_return == PENDING_DEFER)
1833 {
1834 for (addr = addr->next; addr; addr = addr->next)
1835 if (addr->transport_return == PENDING_DEFER)
1836 { /* at least two recipients to send */
1837 prdr_active = TRUE;
1838 sprintf(CS p, " PRDR"); p += 5;
1839 break;
1840 }
1841 break;
1842 }
1843 }
1844 #endif
1845
1846 /* check if all addresses have lasthop flag */
1847 /* do not send RET and ENVID if true */
1848 dsn_all_lasthop = TRUE;
1849 for (addr = first_addr;
1850 address_count < max_rcpt && addr != NULL;
1851 addr = addr->next)
1852 if ((addr->dsn_flags & rf_dsnlasthop) != 1)
1853 dsn_all_lasthop = FALSE;
1854
1855 /* Add any DSN flags to the mail command */
1856
1857 if ((smtp_use_dsn) && (dsn_all_lasthop == FALSE))
1858 {
1859 if (dsn_ret == dsn_ret_hdrs)
1860 {
1861 Ustrcpy(p, " RET=HDRS");
1862 while (*p) p++;
1863 }
1864 else if (dsn_ret == dsn_ret_full)
1865 {
1866 Ustrcpy(p, " RET=FULL");
1867 while (*p) p++;
1868 }
1869 if (dsn_envid != NULL)
1870 {
1871 string_format(p, sizeof(buffer) - (p-buffer), " ENVID=%s", dsn_envid);
1872 while (*p) p++;
1873 }
1874 }
1875
1876 /* If an authenticated_sender override has been specified for this transport
1877 instance, expand it. If the expansion is forced to fail, and there was already
1878 an authenticated_sender for this message, the original value will be used.
1879 Other expansion failures are serious. An empty result is ignored, but there is
1880 otherwise no check - this feature is expected to be used with LMTP and other
1881 cases where non-standard addresses (e.g. without domains) might be required. */
1882
1883 if (smtp_mail_auth_str(p, sizeof(buffer) - (p-buffer), addrlist, ob))
1884 {
1885 yield = ERROR;
1886 goto SEND_QUIT;
1887 }
1888
1889 /* From here until we send the DATA command, we can make use of PIPELINING
1890 if the server host supports it. The code has to be able to check the responses
1891 at any point, for when the buffer fills up, so we write it totally generally.
1892 When PIPELINING is off, each command written reports that it has flushed the
1893 buffer. */
1894
1895 pending_MAIL = TRUE; /* The block starts with MAIL */
1896
1897 rc = smtp_write_command(&outblock, smtp_use_pipelining,
1898 "MAIL FROM:<%s>%s\r\n", return_path, buffer);
1899 mail_command = string_copy(big_buffer); /* Save for later error message */
1900
1901 switch(rc)
1902 {
1903 case -1: /* Transmission error */
1904 goto SEND_FAILED;
1905
1906 case +1: /* Block was sent */
1907 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
1908 ob->command_timeout))
1909 {
1910 if (errno == 0 && buffer[0] == '4')
1911 {
1912 errno = ERRNO_MAIL4XX;
1913 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
1914 }
1915 goto RESPONSE_FAILED;
1916 }
1917 pending_MAIL = FALSE;
1918 break;
1919 }
1920
1921 /* Pass over all the relevant recipient addresses for this host, which are the
1922 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
1923 several before we have to read the responses for those seen so far. This
1924 checking is done by a subroutine because it also needs to be done at the end.
1925 Send only up to max_rcpt addresses at a time, leaving first_addr pointing to
1926 the next one if not all are sent.
1927
1928 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
1929 last address because we want to abort if any recipients have any kind of
1930 problem, temporary or permanent. We know that all recipient addresses will have
1931 the PENDING_DEFER status, because only one attempt is ever made, and we know
1932 that max_rcpt will be large, so all addresses will be done at once. */
1933
1934 for (addr = first_addr;
1935 address_count < max_rcpt && addr != NULL;
1936 addr = addr->next)
1937 {
1938 int count;
1939 BOOL no_flush;
1940
1941 addr->dsn_aware = smtp_use_dsn ? dsn_support_yes : dsn_support_no;
1942
1943 if (addr->transport_return != PENDING_DEFER) continue;
1944
1945 address_count++;
1946 no_flush = smtp_use_pipelining && (!mua_wrapper || addr->next != NULL);
1947
1948 /* Add any DSN flags to the rcpt command and add to the sent string */
1949
1950 p = buffer;
1951 *p = 0;
1952
1953 if (smtp_use_dsn && (addr->dsn_flags & rf_dsnlasthop) != 1)
1954 {
1955 if ((addr->dsn_flags & rf_dsnflags) != 0)
1956 {
1957 int i;
1958 BOOL first = TRUE;
1959 Ustrcpy(p, " NOTIFY=");
1960 while (*p) p++;
1961 for (i = 0; i < 4; i++)
1962 if ((addr->dsn_flags & rf_list[i]) != 0)
1963 {
1964 if (!first) *p++ = ',';
1965 first = FALSE;
1966 Ustrcpy(p, rf_names[i]);
1967 while (*p) p++;
1968 }
1969 }
1970
1971 if (addr->dsn_orcpt != NULL)
1972 {
1973 string_format(p, sizeof(buffer) - (p-buffer), " ORCPT=%s",
1974 addr->dsn_orcpt);
1975 while (*p) p++;
1976 }
1977 }
1978
1979 /* Now send the RCPT command, and process outstanding responses when
1980 necessary. After a timeout on RCPT, we just end the function, leaving the
1981 yield as OK, because this error can often mean that there is a problem with
1982 just one address, so we don't want to delay the host. */
1983
1984 count = smtp_write_command(&outblock, no_flush, "RCPT TO:<%s>%s%s\r\n",
1985 transport_rcpt_address(addr, tblock->rcpt_include_affixes), igquotstr, buffer);
1986
1987 if (count < 0) goto SEND_FAILED;
1988 if (count > 0)
1989 {
1990 switch(sync_responses(first_addr, tblock->rcpt_include_affixes,
1991 &sync_addr, host, count, ob->address_retry_include_sender,
1992 pending_MAIL, 0, &inblock, ob->command_timeout, buffer,
1993 sizeof(buffer)))
1994 {
1995 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
1996 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
1997 break;
1998
1999 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2000 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2001 case 0: /* No 2xx or 5xx, but no probs */
2002 break;
2003
2004 case -1: goto END_OFF; /* Timeout on RCPT */
2005 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL error */
2006 }
2007 pending_MAIL = FALSE; /* Dealt with MAIL */
2008 }
2009 } /* Loop for next address */
2010
2011 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
2012 permanently or temporarily. We should have flushed and synced after the last
2013 RCPT. */
2014
2015 if (mua_wrapper)
2016 {
2017 address_item *badaddr;
2018 for (badaddr = first_addr; badaddr; badaddr = badaddr->next)
2019 if (badaddr->transport_return != PENDING_OK)
2020 {
2021 /*XXX could we find a better errno than 0 here? */
2022 set_errno(addrlist, 0, badaddr->message, FAIL,
2023 testflag(badaddr, af_pass_message), NULL);
2024 ok = FALSE;
2025 break;
2026 }
2027 }
2028
2029 /* If ok is TRUE, we know we have got at least one good recipient, and must now
2030 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
2031 have a good recipient buffered up if we are pipelining. We don't want to waste
2032 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
2033 are pipelining. The responses are all handled by sync_responses(). */
2034
2035 if (ok || (smtp_use_pipelining && !mua_wrapper))
2036 {
2037 int count = smtp_write_command(&outblock, FALSE, "DATA\r\n");
2038 if (count < 0) goto SEND_FAILED;
2039 switch(sync_responses(first_addr, tblock->rcpt_include_affixes, &sync_addr,
2040 host, count, ob->address_retry_include_sender, pending_MAIL,
2041 ok? +1 : -1, &inblock, ob->command_timeout, buffer, sizeof(buffer)))
2042 {
2043 case 3: ok = TRUE; /* 2xx & 5xx => OK & progress made */
2044 case 2: completed_address = TRUE; /* 5xx (only) => progress made */
2045 break;
2046
2047 case 1: ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2048 if (!lmtp) completed_address = TRUE; /* can't tell about progress yet */
2049 case 0: break; /* No 2xx or 5xx, but no probs */
2050
2051 case -1: goto END_OFF; /* Timeout on RCPT */
2052 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2053 }
2054 }
2055
2056 /* Save the first address of the next batch. */
2057
2058 first_addr = addr;
2059
2060 /* If there were no good recipients (but otherwise there have been no
2061 problems), just set ok TRUE, since we have handled address-specific errors
2062 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
2063 for handling the SMTP dot-handling protocol, flagging to apply to headers as
2064 well as body. Set the appropriate timeout value to be used for each chunk.
2065 (Haven't been able to make it work using select() for writing yet.) */
2066
2067 if (!ok) ok = TRUE; else
2068 {
2069 sigalrm_seen = FALSE;
2070 transport_write_timeout = ob->data_timeout;
2071 smtp_command = US"sending data block"; /* For error messages */
2072 DEBUG(D_transport|D_v)
2073 debug_printf(" SMTP>> writing message and terminating \".\"\n");
2074 transport_count = 0;
2075
2076 #ifndef DISABLE_DKIM
2077 ok = dkim_transport_write_message(addrlist, inblock.sock,
2078 topt_use_crlf | topt_end_dot | topt_escape_headers |
2079 (tblock->body_only? topt_no_headers : 0) |
2080 (tblock->headers_only? topt_no_body : 0) |
2081 (tblock->return_path_add? topt_add_return_path : 0) |
2082 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
2083 (tblock->envelope_to_add? topt_add_envelope_to : 0),
2084 0, /* No size limit */
2085 tblock->add_headers, tblock->remove_headers,
2086 US".", US"..", /* Escaping strings */
2087 tblock->rewrite_rules, tblock->rewrite_existflags,
2088 ob->dkim_private_key, ob->dkim_domain, ob->dkim_selector,
2089 ob->dkim_canon, ob->dkim_strict, ob->dkim_sign_headers
2090 );
2091 #else
2092 ok = transport_write_message(addrlist, inblock.sock,
2093 topt_use_crlf | topt_end_dot | topt_escape_headers |
2094 (tblock->body_only? topt_no_headers : 0) |
2095 (tblock->headers_only? topt_no_body : 0) |
2096 (tblock->return_path_add? topt_add_return_path : 0) |
2097 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
2098 (tblock->envelope_to_add? topt_add_envelope_to : 0),
2099 0, /* No size limit */
2100 tblock->add_headers, tblock->remove_headers,
2101 US".", US"..", /* Escaping strings */
2102 tblock->rewrite_rules, tblock->rewrite_existflags);
2103 #endif
2104
2105 /* transport_write_message() uses write() because it is called from other
2106 places to write to non-sockets. This means that under some OS (e.g. Solaris)
2107 it can exit with "Broken pipe" as its error. This really means that the
2108 socket got closed at the far end. */
2109
2110 transport_write_timeout = 0; /* for subsequent transports */
2111
2112 /* Failure can either be some kind of I/O disaster (including timeout),
2113 or the failure of a transport filter or the expansion of added headers. */
2114
2115 if (!ok)
2116 {
2117 buffer[0] = 0; /* There hasn't been a response */
2118 goto RESPONSE_FAILED;
2119 }
2120
2121 /* We used to send the terminating "." explicitly here, but because of
2122 buffering effects at both ends of TCP/IP connections, you don't gain
2123 anything by keeping it separate, so it might as well go in the final
2124 data buffer for efficiency. This is now done by setting the topt_end_dot
2125 flag above. */
2126
2127 smtp_command = US"end of data";
2128
2129 #ifndef DISABLE_PRDR
2130 /* For PRDR we optionally get a partial-responses warning
2131 * followed by the individual responses, before going on with
2132 * the overall response. If we don't get the warning then deal
2133 * with per non-PRDR. */
2134 if(prdr_active)
2135 {
2136 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '3',
2137 ob->final_timeout);
2138 if (!ok && errno == 0)
2139 switch(buffer[0])
2140 {
2141 case '2': prdr_active = FALSE;
2142 ok = TRUE;
2143 break;
2144 case '4': errno = ERRNO_DATA4XX;
2145 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2146 break;
2147 }
2148 }
2149 else
2150 #endif
2151
2152 /* For non-PRDR SMTP, we now read a single response that applies to the
2153 whole message. If it is OK, then all the addresses have been delivered. */
2154
2155 if (!lmtp)
2156 {
2157 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2158 ob->final_timeout);
2159 if (!ok && errno == 0 && buffer[0] == '4')
2160 {
2161 errno = ERRNO_DATA4XX;
2162 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2163 }
2164 }
2165
2166 /* For LMTP, we get back a response for every RCPT command that we sent;
2167 some may be accepted and some rejected. For those that get a response, their
2168 status is fixed; any that are accepted have been handed over, even if later
2169 responses crash - at least, that's how I read RFC 2033.
2170
2171 If all went well, mark the recipient addresses as completed, record which
2172 host/IPaddress they were delivered to, and cut out RSET when sending another
2173 message down the same channel. Write the completed addresses to the journal
2174 now so that they are recorded in case there is a crash of hardware or
2175 software before the spool gets updated. Also record the final SMTP
2176 confirmation if needed (for SMTP only). */
2177
2178 if (ok)
2179 {
2180 int flag = '=';
2181 int delivery_time = (int)(time(NULL) - start_delivery_time);
2182 int len;
2183 host_item *thost;
2184 uschar *conf = NULL;
2185 send_rset = FALSE;
2186
2187 /* Make a copy of the host if it is local to this invocation
2188 of the transport. */
2189
2190 if (copy_host)
2191 {
2192 thost = store_get(sizeof(host_item));
2193 *thost = *host;
2194 thost->name = string_copy(host->name);
2195 thost->address = string_copy(host->address);
2196 }
2197 else thost = host;
2198
2199 /* Set up confirmation if needed - applies only to SMTP */
2200
2201 if (
2202 #ifndef EXPERIMENTAL_EVENT
2203 (log_extra_selector & LX_smtp_confirmation) != 0 &&
2204 #endif
2205 !lmtp
2206 )
2207 {
2208 uschar *s = string_printing(buffer);
2209 conf = (s == buffer)? (uschar *)string_copy(s) : s;
2210 }
2211
2212 /* Process all transported addresses - for LMTP or PRDR, read a status for
2213 each one. */
2214
2215 for (addr = addrlist; addr != first_addr; addr = addr->next)
2216 {
2217 if (addr->transport_return != PENDING_OK) continue;
2218
2219 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
2220 remaining addresses. Otherwise, it's a return code for just the one
2221 address. For temporary errors, add a retry item for the address so that
2222 it doesn't get tried again too soon. */
2223
2224 #ifndef DISABLE_PRDR
2225 if (lmtp || prdr_active)
2226 #else
2227 if (lmtp)
2228 #endif
2229 {
2230 if (!smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2231 ob->final_timeout))
2232 {
2233 if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
2234 addr->message = string_sprintf(
2235 #ifndef DISABLE_PRDR
2236 "%s error after %s: %s", prdr_active ? "PRDR":"LMTP",
2237 #else
2238 "LMTP error after %s: %s",
2239 #endif
2240 big_buffer, string_printing(buffer));
2241 setflag(addr, af_pass_message); /* Allow message to go to user */
2242 if (buffer[0] == '5')
2243 addr->transport_return = FAIL;
2244 else
2245 {
2246 errno = ERRNO_DATA4XX;
2247 addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2248 addr->transport_return = DEFER;
2249 #ifndef DISABLE_PRDR
2250 if (!prdr_active)
2251 #endif
2252 retry_add_item(addr, addr->address_retry_key, 0);
2253 }
2254 continue;
2255 }
2256 completed_address = TRUE; /* NOW we can set this flag */
2257 if ((log_extra_selector & LX_smtp_confirmation) != 0)
2258 {
2259 uschar *s = string_printing(buffer);
2260 conf = (s == buffer)? (uschar *)string_copy(s) : s;
2261 }
2262 }
2263
2264 /* SMTP, or success return from LMTP for this address. Pass back the
2265 actual host that was used. */
2266
2267 addr->transport_return = OK;
2268 addr->more_errno = delivery_time;
2269 addr->host_used = thost;
2270 addr->special_action = flag;
2271 addr->message = conf;
2272 #ifndef DISABLE_PRDR
2273 if (prdr_active) addr->flags |= af_prdr_used;
2274 #endif
2275 flag = '-';
2276
2277 #ifndef DISABLE_PRDR
2278 if (!prdr_active)
2279 #endif
2280 {
2281 /* Update the journal. For homonymic addresses, use the base address plus
2282 the transport name. See lots of comments in deliver.c about the reasons
2283 for the complications when homonyms are involved. Just carry on after
2284 write error, as it may prove possible to update the spool file later. */
2285
2286 if (testflag(addr, af_homonym))
2287 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2288 else
2289 sprintf(CS buffer, "%.500s\n", addr->unique);
2290
2291 DEBUG(D_deliver) debug_printf("journalling %s", buffer);
2292 len = Ustrlen(CS buffer);
2293 if (write(journal_fd, buffer, len) != len)
2294 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2295 "%s: %s", buffer, strerror(errno));
2296 }
2297 }
2298
2299 #ifndef DISABLE_PRDR
2300 if (prdr_active)
2301 {
2302 /* PRDR - get the final, overall response. For any non-success
2303 upgrade all the address statuses. */
2304 ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2305 ob->final_timeout);
2306 if (!ok)
2307 {
2308 if(errno == 0 && buffer[0] == '4')
2309 {
2310 errno = ERRNO_DATA4XX;
2311 addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
2312 }
2313 for (addr = addrlist; addr != first_addr; addr = addr->next)
2314 if (buffer[0] == '5' || addr->transport_return == OK)
2315 addr->transport_return = PENDING_OK; /* allow set_errno action */
2316 goto RESPONSE_FAILED;
2317 }
2318
2319 /* Update the journal, or setup retry. */
2320 for (addr = addrlist; addr != first_addr; addr = addr->next)
2321 if (addr->transport_return == OK)
2322 {
2323 if (testflag(addr, af_homonym))
2324 sprintf(CS buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
2325 else
2326 sprintf(CS buffer, "%.500s\n", addr->unique);
2327
2328 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s", buffer);
2329 len = Ustrlen(CS buffer);
2330 if (write(journal_fd, buffer, len) != len)
2331 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
2332 "%s: %s", buffer, strerror(errno));
2333 }
2334 else if (addr->transport_return == DEFER)
2335 retry_add_item(addr, addr->address_retry_key, -2);
2336 }
2337 #endif
2338
2339 /* Ensure the journal file is pushed out to disk. */
2340
2341 if (EXIMfsync(journal_fd) < 0)
2342 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
2343 strerror(errno));
2344 }
2345 }
2346
2347
2348 /* Handle general (not specific to one address) failures here. The value of ok
2349 is used to skip over this code on the falling through case. A timeout causes a
2350 deferral. Other errors may defer or fail according to the response code, and
2351 may set up a special errno value, e.g. after connection chopped, which is
2352 assumed if errno == 0 and there is no text in the buffer. If control reaches
2353 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
2354 the problem is not related to this specific message. */
2355
2356 if (!ok)
2357 {
2358 int code;
2359
2360 RESPONSE_FAILED:
2361 save_errno = errno;
2362 message = NULL;
2363 send_quit = check_response(host, &save_errno, addrlist->more_errno,
2364 buffer, &code, &message, &pass_message);
2365 goto FAILED;
2366
2367 SEND_FAILED:
2368 save_errno = errno;
2369 code = '4';
2370 message = US string_sprintf("send() to %s [%s] failed: %s",
2371 host->name, host->address, strerror(save_errno));
2372 send_quit = FALSE;
2373 goto FAILED;
2374
2375 /* This label is jumped to directly when a TLS negotiation has failed,
2376 or was not done for a host for which it is required. Values will be set
2377 in message and save_errno, and setting_up will always be true. Treat as
2378 a temporary error. */
2379
2380 #ifdef SUPPORT_TLS
2381 TLS_FAILED:
2382 code = '4';
2383 #endif
2384
2385 /* If the failure happened while setting up the call, see if the failure was
2386 a 5xx response (this will either be on connection, or following HELO - a 5xx
2387 after EHLO causes it to try HELO). If so, fail all addresses, as this host is
2388 never going to accept them. For other errors during setting up (timeouts or
2389 whatever), defer all addresses, and yield DEFER, so that the host is not
2390 tried again for a while. */
2391
2392 FAILED:
2393 ok = FALSE; /* For when reached by GOTO */
2394
2395 if (setting_up)
2396 {
2397 if (code == '5')
2398 set_errno(addrlist, save_errno, message, FAIL, pass_message, host);
2399 else
2400 {
2401 set_errno(addrlist, save_errno, message, DEFER, pass_message, host);
2402 yield = DEFER;
2403 }
2404 }
2405
2406 /* We want to handle timeouts after MAIL or "." and loss of connection after
2407 "." specially. They can indicate a problem with the sender address or with
2408 the contents of the message rather than a real error on the connection. These
2409 cases are treated in the same way as a 4xx response. This next bit of code
2410 does the classification. */
2411
2412 else
2413 {
2414 BOOL message_error;
2415
2416 switch(save_errno)
2417 {
2418 case 0:
2419 case ERRNO_MAIL4XX:
2420 case ERRNO_DATA4XX:
2421 message_error = TRUE;
2422 break;
2423
2424 case ETIMEDOUT:
2425 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
2426 Ustrncmp(smtp_command,"end ",4) == 0;
2427 break;
2428
2429 case ERRNO_SMTPCLOSED:
2430 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
2431 break;
2432
2433 default:
2434 message_error = FALSE;
2435 break;
2436 }
2437
2438 /* Handle the cases that are treated as message errors. These are:
2439
2440 (a) negative response or timeout after MAIL
2441 (b) negative response after DATA
2442 (c) negative response or timeout or dropped connection after "."
2443
2444 It won't be a negative response or timeout after RCPT, as that is dealt
2445 with separately above. The action in all cases is to set an appropriate
2446 error code for all the addresses, but to leave yield set to OK because the
2447 host itself has not failed. Of course, it might in practice have failed
2448 when we've had a timeout, but if so, we'll discover that at the next
2449 delivery attempt. For a temporary error, set the message_defer flag, and
2450 write to the logs for information if this is not the last host. The error
2451 for the last host will be logged as part of the address's log line. */
2452
2453 if (message_error)
2454 {
2455 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
2456 set_errno(addrlist, save_errno, message, (code == '5')? FAIL : DEFER,
2457 pass_message, host);
2458
2459 /* If there's an errno, the message contains just the identity of
2460 the host. */
2461
2462 if (code != '5') /* Anything other than 5 is treated as temporary */
2463 {
2464 if (save_errno > 0)
2465 message = US string_sprintf("%s: %s", message, strerror(save_errno));
2466 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
2467 msglog_line(host, message);
2468 *message_defer = TRUE;
2469 }
2470 }
2471
2472 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
2473 ".", or some other transportation error. We defer all addresses and yield
2474 DEFER, except for the case of failed add_headers expansion, or a transport
2475 filter failure, when the yield should be ERROR, to stop it trying other
2476 hosts. */
2477
2478 else
2479 {
2480 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
2481 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
2482 set_errno(addrlist, save_errno, message, DEFER, pass_message, host);
2483 }
2484 }
2485 }
2486
2487
2488 /* If all has gone well, send_quit will be set TRUE, implying we can end the
2489 SMTP session tidily. However, if there were too many addresses to send in one
2490 message (indicated by first_addr being non-NULL) we want to carry on with the
2491 rest of them. Also, it is desirable to send more than one message down the SMTP
2492 connection if there are several waiting, provided we haven't already sent so
2493 many as to hit the configured limit. The function transport_check_waiting looks
2494 for a waiting message and returns its id. Then transport_pass_socket tries to
2495 set up a continued delivery by passing the socket on to another process. The
2496 variable send_rset is FALSE if a message has just been successfully transfered.
2497
2498 If we are already sending down a continued channel, there may be further
2499 addresses not yet delivered that are aimed at the same host, but which have not
2500 been passed in this run of the transport. In this case, continue_more will be
2501 true, and all we should do is send RSET if necessary, and return, leaving the
2502 channel open.
2503
2504 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
2505 do not want to continue with other messages down the same channel, because that
2506 can lead to looping between two or more messages, all with the same,
2507 temporarily failing address(es). [The retry information isn't updated yet, so
2508 new processes keep on trying.] We probably also don't want to try more of this
2509 message's addresses either.
2510
2511 If we have started a TLS session, we have to end it before passing the
2512 connection to a new process. However, not all servers can handle this (Exim
2513 can), so we do not pass such a connection on if the host matches
2514 hosts_nopass_tls. */
2515
2516 DEBUG(D_transport)
2517 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
2518 "yield=%d first_address is %sNULL\n", ok, send_quit, send_rset,
2519 continue_more, yield, (first_addr == NULL)? "":"not ");
2520
2521 if (completed_address && ok && send_quit)
2522 {
2523 BOOL more;
2524 if ( first_addr != NULL
2525 || continue_more
2526 || ( ( tls_out.active < 0
2527 || verify_check_given_host(&ob->hosts_nopass_tls, host) != OK
2528 )
2529 &&
2530 transport_check_waiting(tblock->name, host->name,
2531 tblock->connection_max_messages, new_message_id, &more)
2532 ) )
2533 {
2534 uschar *msg;
2535 BOOL pass_message;
2536
2537 if (send_rset)
2538 {
2539 if (! (ok = smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0))
2540 {
2541 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
2542 host->address, strerror(save_errno));
2543 send_quit = FALSE;
2544 }
2545 else if (! (ok = smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2546 ob->command_timeout)))
2547 {
2548 int code;
2549 send_quit = check_response(host, &errno, 0, buffer, &code, &msg,
2550 &pass_message);
2551 if (!send_quit)
2552 {
2553 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
2554 host->name, host->address, msg);
2555 }
2556 }
2557 }
2558
2559 /* Either RSET was not needed, or it succeeded */
2560
2561 if (ok)
2562 {
2563 if (first_addr != NULL) /* More addresses still to be sent */
2564 { /* in this run of the transport */
2565 continue_sequence++; /* Causes * in logging */
2566 goto SEND_MESSAGE;
2567 }
2568 if (continue_more) return yield; /* More addresses for another run */
2569
2570 /* Pass the socket to a new Exim process. Before doing so, we must shut
2571 down TLS. Not all MTAs allow for the continuation of the SMTP session
2572 when TLS is shut down. We test for this by sending a new EHLO. If we
2573 don't get a good response, we don't attempt to pass the socket on. */
2574
2575 #ifdef SUPPORT_TLS
2576 if (tls_out.active >= 0)
2577 {
2578 tls_close(FALSE, TRUE);
2579 if (smtps)
2580 ok = FALSE;
2581 else
2582 ok = smtp_write_command(&outblock,FALSE,"EHLO %s\r\n",helo_data) >= 0 &&
2583 smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2584 ob->command_timeout);
2585 }
2586 #endif
2587
2588 /* If the socket is successfully passed, we musn't send QUIT (or
2589 indeed anything!) from here. */
2590
2591 if (ok && transport_pass_socket(tblock->name, host->name, host->address,
2592 new_message_id, inblock.sock))
2593 {
2594 send_quit = FALSE;
2595 }
2596 }
2597
2598 /* If RSET failed and there are addresses left, they get deferred. */
2599
2600 else set_errno(first_addr, errno, msg, DEFER, FALSE, host);
2601 }
2602 }
2603
2604 /* End off tidily with QUIT unless the connection has died or the socket has
2605 been passed to another process. There has been discussion on the net about what
2606 to do after sending QUIT. The wording of the RFC suggests that it is necessary
2607 to wait for a response, but on the other hand, there isn't anything one can do
2608 with an error response, other than log it. Exim used to do that. However,
2609 further discussion suggested that it is positively advantageous not to wait for
2610 the response, but to close the session immediately. This is supposed to move
2611 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
2612 load from the server. (Hosts that are both servers and clients may not see much
2613 difference, of course.) Further discussion indicated that this was safe to do
2614 on Unix systems which have decent implementations of TCP/IP that leave the
2615 connection around for a while (TIME_WAIT) after the application has gone away.
2616 This enables the response sent by the server to be properly ACKed rather than
2617 timed out, as can happen on broken TCP/IP implementations on other OS.
2618
2619 This change is being made on 31-Jul-98. After over a year of trouble-free
2620 operation, the old commented-out code was removed on 17-Sep-99. */
2621
2622 SEND_QUIT:
2623 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2624
2625 END_OFF:
2626
2627 #ifdef SUPPORT_TLS
2628 tls_close(FALSE, TRUE);
2629 #endif
2630
2631 /* Close the socket, and return the appropriate value, first setting
2632 works because the NULL setting is passed back to the calling process, and
2633 remote_max_parallel is forced to 1 when delivering over an existing connection,
2634
2635 If all went well and continue_more is set, we shouldn't actually get here if
2636 there are further addresses, as the return above will be taken. However,
2637 writing RSET might have failed, or there may be other addresses whose hosts are
2638 specified in the transports, and therefore not visible at top level, in which
2639 case continue_more won't get set. */
2640
2641 (void)close(inblock.sock);
2642
2643 #ifdef EXPERIMENTAL_EVENT
2644 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
2645 #endif
2646
2647 continue_transport = NULL;
2648 continue_hostname = NULL;
2649 return yield;
2650 }
2651
2652
2653
2654
2655 /*************************************************
2656 * Closedown entry point *
2657 *************************************************/
2658
2659 /* This function is called when exim is passed an open smtp channel
2660 from another incarnation, but the message which it has been asked
2661 to deliver no longer exists. The channel is on stdin.
2662
2663 We might do fancy things like looking for another message to send down
2664 the channel, but if the one we sought has gone, it has probably been
2665 delivered by some other process that itself will seek further messages,
2666 so just close down our connection.
2667
2668 Argument: pointer to the transport instance block
2669 Returns: nothing
2670 */
2671
2672 void
2673 smtp_transport_closedown(transport_instance *tblock)
2674 {
2675 smtp_transport_options_block *ob =
2676 (smtp_transport_options_block *)(tblock->options_block);
2677 smtp_inblock inblock;
2678 smtp_outblock outblock;
2679 uschar buffer[256];
2680 uschar inbuffer[4096];
2681 uschar outbuffer[16];
2682
2683 inblock.sock = fileno(stdin);
2684 inblock.buffer = inbuffer;
2685 inblock.buffersize = sizeof(inbuffer);
2686 inblock.ptr = inbuffer;
2687 inblock.ptrend = inbuffer;
2688
2689 outblock.sock = inblock.sock;
2690 outblock.buffersize = sizeof(outbuffer);
2691 outblock.buffer = outbuffer;
2692 outblock.ptr = outbuffer;
2693 outblock.cmd_count = 0;
2694 outblock.authenticating = FALSE;
2695
2696 (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
2697 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
2698 ob->command_timeout);
2699 (void)close(inblock.sock);
2700 }
2701
2702
2703
2704 /*************************************************
2705 * Prepare addresses for delivery *
2706 *************************************************/
2707
2708 /* This function is called to flush out error settings from previous delivery
2709 attempts to other hosts. It also records whether we got here via an MX record
2710 or not in the more_errno field of the address. We are interested only in
2711 addresses that are still marked DEFER - others may have got delivered to a
2712 previously considered IP address. Set their status to PENDING_DEFER to indicate
2713 which ones are relevant this time.
2714
2715 Arguments:
2716 addrlist the list of addresses
2717 host the host we are delivering to
2718
2719 Returns: the first address for this delivery
2720 */
2721
2722 static address_item *
2723 prepare_addresses(address_item *addrlist, host_item *host)
2724 {
2725 address_item *first_addr = NULL;
2726 address_item *addr;
2727 for (addr = addrlist; addr != NULL; addr = addr->next)
2728 if (addr->transport_return == DEFER)
2729 {
2730 if (first_addr == NULL) first_addr = addr;
2731 addr->transport_return = PENDING_DEFER;
2732 addr->basic_errno = 0;
2733 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
2734 addr->message = NULL;
2735 #ifdef SUPPORT_TLS
2736 addr->cipher = NULL;
2737 addr->ourcert = NULL;
2738 addr->peercert = NULL;
2739 addr->peerdn = NULL;
2740 addr->ocsp = OCSP_NOT_REQ;
2741 #endif
2742 }
2743 return first_addr;
2744 }
2745
2746
2747
2748 /*************************************************
2749 * Main entry point *
2750 *************************************************/
2751
2752 /* See local README for interface details. As this is a remote transport, it is
2753 given a chain of addresses to be delivered in one connection, if possible. It
2754 always returns TRUE, indicating that each address has its own independent
2755 status set, except if there is a setting up problem, in which case it returns
2756 FALSE. */
2757
2758 BOOL
2759 smtp_transport_entry(
2760 transport_instance *tblock, /* data for this instantiation */
2761 address_item *addrlist) /* addresses we are working on */
2762 {
2763 int cutoff_retry;
2764 int port;
2765 int hosts_defer = 0;
2766 int hosts_fail = 0;
2767 int hosts_looked_up = 0;
2768 int hosts_retry = 0;
2769 int hosts_serial = 0;
2770 int hosts_total = 0;
2771 int total_hosts_tried = 0;
2772 address_item *addr;
2773 BOOL expired = TRUE;
2774 BOOL continuing = continue_hostname != NULL;
2775 uschar *expanded_hosts = NULL;
2776 uschar *pistring;
2777 uschar *tid = string_sprintf("%s transport", tblock->name);
2778 smtp_transport_options_block *ob =
2779 (smtp_transport_options_block *)(tblock->options_block);
2780 host_item *hostlist = addrlist->host_list;
2781 host_item *host = NULL;
2782
2783 DEBUG(D_transport)
2784 {
2785 debug_printf("%s transport entered\n", tblock->name);
2786 for (addr = addrlist; addr != NULL; addr = addr->next)
2787 debug_printf(" %s\n", addr->address);
2788 if (continuing) debug_printf("already connected to %s [%s]\n",
2789 continue_hostname, continue_host_address);
2790 }
2791
2792 /* Set the flag requesting that these hosts be added to the waiting
2793 database if the delivery fails temporarily or if we are running with
2794 queue_smtp or a 2-stage queue run. This gets unset for certain
2795 kinds of error, typically those that are specific to the message. */
2796
2797 update_waiting = TRUE;
2798
2799 /* If a host list is not defined for the addresses - they must all have the
2800 same one in order to be passed to a single transport - or if the transport has
2801 a host list with hosts_override set, use the host list supplied with the
2802 transport. It is an error for this not to exist. */
2803
2804 if (hostlist == NULL || (ob->hosts_override && ob->hosts != NULL))
2805 {
2806 if (ob->hosts == NULL)
2807 {
2808 addrlist->message = string_sprintf("%s transport called with no hosts set",
2809 tblock->name);
2810 addrlist->transport_return = PANIC;
2811 return FALSE; /* Only top address has status */
2812 }
2813
2814 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
2815 ob->hosts);
2816
2817 /* If the transport's host list contains no '$' characters, and we are not
2818 randomizing, it is fixed and therefore a chain of hosts can be built once
2819 and for all, and remembered for subsequent use by other calls to this
2820 transport. If, on the other hand, the host list does contain '$', or we are
2821 randomizing its order, we have to rebuild it each time. In the fixed case,
2822 as the hosts string will never be used again, it doesn't matter that we
2823 replace all the : characters with zeros. */
2824
2825 if (ob->hostlist == NULL)
2826 {
2827 uschar *s = ob->hosts;
2828
2829 if (Ustrchr(s, '$') != NULL)
2830 {
2831 expanded_hosts = expand_string(s);
2832 if (expanded_hosts == NULL)
2833 {
2834 addrlist->message = string_sprintf("failed to expand list of hosts "
2835 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
2836 addrlist->transport_return = search_find_defer? DEFER : PANIC;
2837 return FALSE; /* Only top address has status */
2838 }
2839 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
2840 "\"%s\"\n", s, expanded_hosts);
2841 s = expanded_hosts;
2842 }
2843 else
2844 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
2845
2846 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
2847
2848 /* Check that the expansion yielded something useful. */
2849 if (hostlist == NULL)
2850 {
2851 addrlist->message =
2852 string_sprintf("%s transport has empty hosts setting", tblock->name);
2853 addrlist->transport_return = PANIC;
2854 return FALSE; /* Only top address has status */
2855 }
2856
2857 /* If there was no expansion of hosts, save the host list for
2858 next time. */
2859
2860 if (expanded_hosts == NULL) ob->hostlist = hostlist;
2861 }
2862
2863 /* This is not the first time this transport has been run in this delivery;
2864 the host list was built previously. */
2865
2866 else hostlist = ob->hostlist;
2867 }
2868
2869 /* The host list was supplied with the address. If hosts_randomize is set, we
2870 must sort it into a random order if it did not come from MX records and has not
2871 already been randomized (but don't bother if continuing down an existing
2872 connection). */
2873
2874 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continuing)
2875 {
2876 host_item *newlist = NULL;
2877 while (hostlist != NULL)
2878 {
2879 host_item *h = hostlist;
2880 hostlist = hostlist->next;
2881
2882 h->sort_key = random_number(100);
2883
2884 if (newlist == NULL)
2885 {
2886 h->next = NULL;
2887 newlist = h;
2888 }
2889 else if (h->sort_key < newlist->sort_key)
2890 {
2891 h->next = newlist;
2892 newlist = h;
2893 }
2894 else
2895 {
2896 host_item *hh = newlist;
2897 while (hh->next != NULL)
2898 {
2899 if (h->sort_key < hh->next->sort_key) break;
2900 hh = hh->next;
2901 }
2902 h->next = hh->next;
2903 hh->next = h;
2904 }
2905 }
2906
2907 hostlist = addrlist->host_list = newlist;
2908 }
2909
2910
2911 /* Sort out the default port. */
2912
2913 if (!smtp_get_port(ob->port, addrlist, &port, tid)) return FALSE;
2914
2915
2916 /* For each host-plus-IP-address on the list:
2917
2918 . If this is a continued delivery and the host isn't the one with the
2919 current connection, skip.
2920
2921 . If the status is unusable (i.e. previously failed or retry checked), skip.
2922
2923 . If no IP address set, get the address, either by turning the name into
2924 an address, calling gethostbyname if gethostbyname is on, or by calling
2925 the DNS. The DNS may yield multiple addresses, in which case insert the
2926 extra ones into the list.
2927
2928 . Get the retry data if not previously obtained for this address and set the
2929 field which remembers the state of this address. Skip if the retry time is
2930 not reached. If not, remember whether retry data was found. The retry string
2931 contains both the name and the IP address.
2932
2933 . Scan the list of addresses and mark those whose status is DEFER as
2934 PENDING_DEFER. These are the only ones that will be processed in this cycle
2935 of the hosts loop.
2936
2937 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
2938 Some addresses may be successfully delivered, others may fail, and yet
2939 others may get temporary errors and so get marked DEFER.
2940
2941 . The return from the delivery attempt is OK if a connection was made and a
2942 valid SMTP dialogue was completed. Otherwise it is DEFER.
2943
2944 . If OK, add a "remove" retry item for this host/IPaddress, if any.
2945
2946 . If fail to connect, or other defer state, add a retry item.
2947
2948 . If there are any addresses whose status is still DEFER, carry on to the
2949 next host/IPaddress, unless we have tried the number of hosts given
2950 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
2951 there is some fancy logic for hosts_max_try that means its limit can be
2952 overstepped in some circumstances.
2953
2954 If we get to the end of the list, all hosts have deferred at least one address,
2955 or not reached their retry times. If delay_after_cutoff is unset, it requests a
2956 delivery attempt to those hosts whose last try was before the arrival time of
2957 the current message. To cope with this, we have to go round the loop a second
2958 time. After that, set the status and error data for any addresses that haven't
2959 had it set already. */
2960
2961 for (cutoff_retry = 0; expired &&
2962 cutoff_retry < ((ob->delay_after_cutoff)? 1 : 2);
2963 cutoff_retry++)
2964 {
2965 host_item *nexthost = NULL;
2966 int unexpired_hosts_tried = 0;
2967
2968 for (host = hostlist;
2969 host != NULL &&
2970 unexpired_hosts_tried < ob->hosts_max_try &&
2971 total_hosts_tried < ob->hosts_max_try_hardlimit;
2972 host = nexthost)
2973 {
2974 int rc;
2975 int host_af;
2976 uschar *rs;
2977 BOOL serialized = FALSE;
2978 BOOL host_is_expired = FALSE;
2979 BOOL message_defer = FALSE;
2980 BOOL ifchanges = FALSE;
2981 BOOL some_deferred = FALSE;
2982 address_item *first_addr = NULL;
2983 uschar *interface = NULL;
2984 uschar *retry_host_key = NULL;
2985 uschar *retry_message_key = NULL;
2986 uschar *serialize_key = NULL;
2987
2988 /* Default next host is next host. :-) But this can vary if the
2989 hosts_max_try limit is hit (see below). It may also be reset if a host
2990 address is looked up here (in case the host was multihomed). */
2991
2992 nexthost = host->next;
2993
2994 /* If the address hasn't yet been obtained from the host name, look it up
2995 now, unless the host is already marked as unusable. If it is marked as
2996 unusable, it means that the router was unable to find its IP address (in
2997 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
2998 the lookup failed last time. We don't get this far if *all* MX records
2999 point to non-existent hosts; that is treated as a hard error.
3000
3001 We can just skip this host entirely. When the hosts came from the router,
3002 the address will timeout based on the other host(s); when the address is
3003 looked up below, there is an explicit retry record added.
3004
3005 Note that we mustn't skip unusable hosts if the address is not unset; they
3006 may be needed as expired hosts on the 2nd time round the cutoff loop. */
3007
3008 if (host->address == NULL)
3009 {
3010 int new_port, flags;
3011 host_item *hh;
3012 uschar *canonical_name;
3013
3014 if (host->status >= hstatus_unusable)
3015 {
3016 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
3017 host->name);
3018 continue;
3019 }
3020
3021 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
3022
3023 /* The host name is permitted to have an attached port. Find it, and
3024 strip it from the name. Just remember it for now. */
3025
3026 new_port = host_item_get_port(host);
3027
3028 /* Count hosts looked up */
3029
3030 hosts_looked_up++;
3031
3032 /* Find by name if so configured, or if it's an IP address. We don't
3033 just copy the IP address, because we need the test-for-local to happen. */
3034
3035 flags = HOST_FIND_BY_A;
3036 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
3037 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
3038
3039 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
3040 rc = host_find_byname(host, NULL, flags, &canonical_name, TRUE);
3041 else
3042 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
3043 ob->dnssec_request_domains, ob->dnssec_require_domains,
3044 &canonical_name, NULL);
3045
3046 /* Update the host (and any additional blocks, resulting from
3047 multihoming) with a host-specific port, if any. */
3048
3049 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
3050
3051 /* Failure to find the host at this time (usually DNS temporary failure)
3052 is really a kind of routing failure rather than a transport failure.
3053 Therefore we add a retry item of the routing kind, not to stop us trying
3054 to look this name up here again, but to ensure the address gets timed
3055 out if the failures go on long enough. A complete failure at this point
3056 commonly points to a configuration error, but the best action is still
3057 to carry on for the next host. */
3058
3059 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
3060 {
3061 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
3062 expired = FALSE;
3063 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
3064 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
3065 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
3066 host->status = hstatus_unusable;
3067
3068 for (addr = addrlist; addr != NULL; addr = addr->next)
3069 {
3070 if (addr->transport_return != DEFER) continue;
3071 addr->basic_errno = ERRNO_UNKNOWNHOST;
3072 addr->message =
3073 string_sprintf("failed to lookup IP address for %s", host->name);
3074 }
3075 continue;
3076 }
3077
3078 /* If the host is actually the local host, we may have a problem, or
3079 there may be some cunning configuration going on. In the problem case,
3080 log things and give up. The default transport status is already DEFER. */
3081
3082 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
3083 {
3084 for (addr = addrlist; addr != NULL; addr = addr->next)
3085 {
3086 addr->basic_errno = 0;
3087 addr->message = string_sprintf("%s transport found host %s to be "
3088 "local", tblock->name, host->name);
3089 }
3090 goto END_TRANSPORT;
3091 }
3092 } /* End of block for IP address lookup */
3093
3094 /* If this is a continued delivery, we are interested only in the host
3095 which matches the name of the existing open channel. The check is put
3096 here after the local host lookup, in case the name gets expanded as a
3097 result of the lookup. Set expired FALSE, to save the outer loop executing
3098 twice. */
3099
3100 if (continuing && (Ustrcmp(continue_hostname, host->name) != 0 ||
3101 Ustrcmp(continue_host_address, host->address) != 0))
3102 {
3103 expired = FALSE;
3104 continue; /* With next host */
3105 }
3106
3107 /* Reset the default next host in case a multihomed host whose addresses
3108 are not looked up till just above added to the host list. */
3109
3110 nexthost = host->next;
3111
3112 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
3113 domain is in queue_smtp_domains, we don't actually want to attempt any
3114 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
3115 there is a lookup defer in queue_smtp_domains, proceed as if the domain
3116 were not in it. We don't want to hold up all SMTP deliveries! Except when
3117 doing a two-stage queue run, don't do this if forcing. */
3118
3119 if ((!deliver_force || queue_2stage) && (queue_smtp ||
3120 match_isinlist(addrlist->domain, &queue_smtp_domains, 0,
3121 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
3122 {
3123 expired = FALSE;
3124 for (addr = addrlist; addr != NULL; addr = addr->next)
3125 {
3126 if (addr->transport_return != DEFER) continue;
3127 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
3128 }
3129 continue; /* With next host */
3130 }
3131
3132 /* Count hosts being considered - purely for an intelligent comment
3133 if none are usable. */
3134
3135 hosts_total++;
3136
3137 /* Set $host and $host address now in case they are needed for the
3138 interface expansion or the serialize_hosts check; they remain set if an
3139 actual delivery happens. */
3140
3141 deliver_host = host->name;
3142 deliver_host_address = host->address;
3143 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
3144 : host->dnssec == DS_NO ? US"no"
3145 : US"";
3146
3147 /* Set up a string for adding to the retry key if the port number is not
3148 the standard SMTP port. A host may have its own port setting that overrides
3149 the default. */
3150
3151 pistring = string_sprintf(":%d", (host->port == PORT_NONE)?
3152 port : host->port);
3153 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
3154
3155 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
3156 string changes upon expansion, we must add it to the key that is used for
3157 retries, because connections to the same host from a different interface
3158 should be treated separately. */
3159
3160 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET : AF_INET6;
3161 if (!smtp_get_interface(ob->interface, host_af, addrlist, &ifchanges,
3162 &interface, tid))
3163 return FALSE;
3164 if (ifchanges) pistring = string_sprintf("%s/%s", pistring, interface);
3165
3166 /* The first time round the outer loop, check the status of the host by
3167 inspecting the retry data. The second time round, we are interested only
3168 in expired hosts that haven't been tried since this message arrived. */
3169
3170 if (cutoff_retry == 0)
3171 {
3172 BOOL incl_ip;
3173 /* Ensure the status of the address is set by checking retry data if
3174 necessary. There may be host-specific retry data (applicable to all
3175 messages) and also data for retries of a specific message at this host.
3176 If either of these retry records are actually read, the keys used are
3177 returned to save recomputing them later. */
3178
3179 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3180 US"retry_include_ip_address", ob->retry_include_ip_address,
3181 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3182 continue; /* with next host */
3183
3184 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
3185 incl_ip, &retry_host_key, &retry_message_key);
3186
3187 DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
3188 (host->address == NULL)? US"" : host->address, pistring,
3189 (host->status == hstatus_usable)? "usable" :
3190 (host->status == hstatus_unusable)? "unusable" :
3191 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
3192
3193 /* Skip this address if not usable at this time, noting if it wasn't
3194 actually expired, both locally and in the address. */
3195
3196 switch (host->status)
3197 {
3198 case hstatus_unusable:
3199 expired = FALSE;
3200 setflag(addrlist, af_retry_skipped);
3201 /* Fall through */
3202
3203 case hstatus_unusable_expired:
3204 switch (host->why)
3205 {
3206 case hwhy_retry: hosts_retry++; break;
3207 case hwhy_failed: hosts_fail++; break;
3208 case hwhy_deferred: hosts_defer++; break;
3209 }
3210
3211 /* If there was a retry message key, implying that previously there
3212 was a message-specific defer, we don't want to update the list of
3213 messages waiting for these hosts. */
3214
3215 if (retry_message_key != NULL) update_waiting = FALSE;
3216 continue; /* With the next host or IP address */
3217 }
3218 }
3219
3220 /* Second time round the loop: if the address is set but expired, and
3221 the message is newer than the last try, let it through. */
3222
3223 else
3224 {
3225 if (host->address == NULL ||
3226 host->status != hstatus_unusable_expired ||
3227 host->last_try > received_time)
3228 continue;
3229 DEBUG(D_transport)
3230 debug_printf("trying expired host %s [%s]%s\n",
3231 host->name, host->address, pistring);
3232 host_is_expired = TRUE;
3233 }
3234
3235 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
3236 it remains TRUE only if all hosts are expired and none are actually tried.
3237 */
3238
3239 expired = FALSE;
3240
3241 /* If this host is listed as one to which access must be serialized,
3242 see if another Exim process has a connection to it, and if so, skip
3243 this host. If not, update the database to record our connection to it
3244 and remember this for later deletion. Do not do any of this if we are
3245 sending the message down a pre-existing connection. */
3246
3247 if (!continuing &&
3248 verify_check_given_host(&ob->serialize_hosts, host) == OK)
3249 {
3250 serialize_key = string_sprintf("host-serialize-%s", host->name);
3251 if (!enq_start(serialize_key))
3252 {
3253 DEBUG(D_transport)
3254 debug_printf("skipping host %s because another Exim process "
3255 "is connected to it\n", host->name);
3256 hosts_serial++;
3257 continue;
3258 }
3259 serialized = TRUE;
3260 }
3261
3262 /* OK, we have an IP address that is not waiting for its retry time to
3263 arrive (it might be expired) OR (second time round the loop) we have an
3264 expired host that hasn't been tried since the message arrived. Have a go
3265 at delivering the message to it. First prepare the addresses by flushing
3266 out the result of previous attempts, and finding the first address that
3267 is still to be delivered. */
3268
3269 first_addr = prepare_addresses(addrlist, host);
3270
3271 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
3272 message_id, host->name, host->address, addrlist->address,
3273 (addrlist->next == NULL)? "" : ", ...");
3274
3275 set_process_info("delivering %s to %s [%s] (%s%s)",
3276 message_id, host->name, host->address, addrlist->address,
3277 (addrlist->next == NULL)? "" : ", ...");
3278
3279 /* This is not for real; don't do the delivery. If there are
3280 any remaining hosts, list them. */
3281
3282 if (dont_deliver)
3283 {
3284 host_item *host2;
3285 set_errno(addrlist, 0, NULL, OK, FALSE, NULL);
3286 for (addr = addrlist; addr != NULL; addr = addr->next)
3287 {
3288 addr->host_used = host;
3289 addr->special_action = '*';
3290 addr->message = US"delivery bypassed by -N option";
3291 }
3292 DEBUG(D_transport)
3293 {
3294 debug_printf("*** delivery by %s transport bypassed by -N option\n"
3295 "*** host and remaining hosts:\n", tblock->name);
3296 for (host2 = host; host2 != NULL; host2 = host2->next)
3297 debug_printf(" %s [%s]\n", host2->name,
3298 (host2->address == NULL)? US"unset" : host2->address);
3299 }
3300 rc = OK;
3301 }
3302
3303 /* This is for real. If the host is expired, we don't count it for
3304 hosts_max_retry. This ensures that all hosts must expire before an address
3305 is timed out, unless hosts_max_try_hardlimit (which protects against
3306 lunatic DNS configurations) is reached.
3307
3308 If the host is not expired and we are about to hit the hosts_max_retry
3309 limit, check to see if there is a subsequent hosts with a different MX
3310 value. If so, make that the next host, and don't count this one. This is a
3311 heuristic to make sure that different MXs do get tried. With a normal kind
3312 of retry rule, they would get tried anyway when the earlier hosts were
3313 delayed, but if the domain has a "retry every time" type of rule - as is
3314 often used for the the very large ISPs, that won't happen. */
3315
3316 else
3317 {
3318 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
3319 {
3320 host_item *h;
3321 DEBUG(D_transport)
3322 debug_printf("hosts_max_try limit reached with this host\n");
3323 for (h = host; h != NULL; h = h->next)
3324 if (h->mx != host->mx) break;
3325 if (h != NULL)
3326 {
3327 nexthost = h;
3328 unexpired_hosts_tried--;
3329 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
3330 "and will be tried\n");
3331 }
3332 }
3333
3334 /* Attempt the delivery. */
3335
3336 total_hosts_tried++;
3337 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
3338 expanded_hosts != NULL, &message_defer, FALSE);
3339
3340 /* Yield is one of:
3341 OK => connection made, each address contains its result;
3342 message_defer is set for message-specific defers (when all
3343 recipients are marked defer)
3344 DEFER => there was a non-message-specific delivery problem;
3345 ERROR => there was a problem setting up the arguments for a filter,
3346 or there was a problem with expanding added headers
3347 */
3348
3349 /* If the result is not OK, there was a non-message-specific problem.
3350 If the result is DEFER, we need to write to the logs saying what happened
3351 for this particular host, except in the case of authentication and TLS
3352 failures, where the log has already been written. If all hosts defer a
3353 general message is written at the end. */
3354
3355 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL &&
3356 first_addr->basic_errno != ERRNO_TLSFAILURE)
3357 write_logs(first_addr, host);
3358
3359 #ifdef EXPERIMENTAL_EVENT
3360 if (rc == DEFER)
3361 deferred_event_raise(first_addr, host);
3362 #endif
3363
3364 /* If STARTTLS was accepted, but there was a failure in setting up the
3365 TLS session (usually a certificate screwup), and the host is not in
3366 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
3367 TLS forcibly turned off. We have to start from scratch with a new SMTP
3368 connection. That's why the retry is done from here, not from within
3369 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
3370 session, so the in-clear transmission after those errors, if permitted,
3371 happens inside smtp_deliver().] */
3372
3373 #ifdef SUPPORT_TLS
3374 if ( rc == DEFER
3375 && first_addr->basic_errno == ERRNO_TLSFAILURE
3376 && ob->tls_tempfail_tryclear
3377 && verify_check_given_host(&ob->hosts_require_tls, host) != OK
3378 )
3379 {
3380 log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
3381 "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
3382 first_addr = prepare_addresses(addrlist, host);
3383 rc = smtp_deliver(addrlist, host, host_af, port, interface, tblock,
3384 expanded_hosts != NULL, &message_defer, TRUE);
3385 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
3386 write_logs(first_addr, host);
3387 # ifdef EXPERIMENTAL_EVENT
3388 if (rc == DEFER)
3389 deferred_event_raise(first_addr, host);
3390 # endif
3391 }
3392 #endif /*SUPPORT_TLS*/
3393 }
3394
3395 /* Delivery attempt finished */
3396
3397 rs = (rc == OK)? US"OK" : (rc == DEFER)? US"DEFER" : (rc == ERROR)?
3398 US"ERROR" : US"?";
3399
3400 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
3401 message_id, host->name, host->address, addrlist->address,
3402 (addrlist->next == NULL)? "" : " (& others)", rs);
3403
3404 /* Release serialization if set up */
3405
3406 if (serialized) enq_end(serialize_key);
3407
3408 /* If the result is DEFER, or if a host retry record is known to exist, we
3409 need to add an item to the retry chain for updating the retry database
3410 at the end of delivery. We only need to add the item to the top address,
3411 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
3412 for any other delivery attempts using the same address. (It is copied into
3413 the unusable tree at the outer level, so even if different address blocks
3414 contain the same address, it still won't get tried again.) */
3415
3416 if (rc == DEFER || retry_host_key != NULL)
3417 {
3418 int delete_flag = (rc != DEFER)? rf_delete : 0;
3419 if (retry_host_key == NULL)
3420 {
3421 BOOL incl_ip;
3422 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3423 US"retry_include_ip_address", ob->retry_include_ip_address,
3424 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3425 incl_ip = TRUE; /* error; use most-specific retry record */
3426
3427 retry_host_key = incl_ip ?
3428 string_sprintf("T:%S:%s%s", host->name, host->address, pistring) :
3429 string_sprintf("T:%S%s", host->name, pistring);
3430 }
3431
3432 /* If a delivery of another message over an existing SMTP connection
3433 yields DEFER, we do NOT set up retry data for the host. This covers the
3434 case when there are delays in routing the addresses in the second message
3435 that are so long that the server times out. This is alleviated by not
3436 routing addresses that previously had routing defers when handling an
3437 existing connection, but even so, this case may occur (e.g. if a
3438 previously happily routed address starts giving routing defers). If the
3439 host is genuinely down, another non-continued message delivery will
3440 notice it soon enough. */
3441
3442 if (delete_flag != 0 || !continuing)
3443 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
3444
3445 /* We may have tried an expired host, if its retry time has come; ensure
3446 the status reflects the expiry for the benefit of any other addresses. */
3447
3448 if (rc == DEFER)
3449 {
3450 host->status = (host_is_expired)?
3451 hstatus_unusable_expired : hstatus_unusable;
3452 host->why = hwhy_deferred;
3453 }
3454 }
3455
3456 /* If message_defer is set (host was OK, but every recipient got deferred
3457 because of some message-specific problem), or if that had happened
3458 previously so that a message retry key exists, add an appropriate item
3459 to the retry chain. Note that if there was a message defer but now there is
3460 a host defer, the message defer record gets deleted. That seems perfectly
3461 reasonable. Also, stop the message from being remembered as waiting
3462 for specific hosts. */
3463
3464 if (message_defer || retry_message_key != NULL)
3465 {
3466 int delete_flag = message_defer? 0 : rf_delete;
3467 if (retry_message_key == NULL)
3468 {
3469 BOOL incl_ip;
3470 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
3471 US"retry_include_ip_address", ob->retry_include_ip_address,
3472 ob->expand_retry_include_ip_address, &incl_ip) != OK)
3473 incl_ip = TRUE; /* error; use most-specific retry record */
3474
3475 retry_message_key = incl_ip ?
3476 string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
3477 message_id) :
3478 string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
3479 }
3480 retry_add_item(addrlist, retry_message_key,
3481 rf_message | rf_host | delete_flag);
3482 update_waiting = FALSE;
3483 }
3484
3485 /* Any return other than DEFER (that is, OK or ERROR) means that the
3486 addresses have got their final statuses filled in for this host. In the OK
3487 case, see if any of them are deferred. */
3488
3489 if (rc == OK)
3490 {
3491 for (addr = addrlist; addr != NULL; addr = addr->next)
3492 {
3493 if (addr->transport_return == DEFER)
3494 {
3495 some_deferred = TRUE;
3496 break;
3497 }
3498 }
3499 }
3500
3501 /* If no addresses deferred or the result was ERROR, return. We do this for
3502 ERROR because a failing filter set-up or add_headers expansion is likely to
3503 fail for any host we try. */
3504
3505 if (rc == ERROR || (rc == OK && !some_deferred))
3506 {
3507 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3508 return TRUE; /* Each address has its status */
3509 }
3510
3511 /* If the result was DEFER or some individual addresses deferred, let
3512 the loop run to try other hosts with the deferred addresses, except for the
3513 case when we were trying to deliver down an existing channel and failed.
3514 Don't try any other hosts in this case. */
3515
3516 if (continuing) break;
3517
3518 /* If the whole delivery, or some individual addresses, were deferred and
3519 there are more hosts that could be tried, do not count this host towards
3520 the hosts_max_try limit if the age of the message is greater than the
3521 maximum retry time for this host. This means we may try try all hosts,
3522 ignoring the limit, when messages have been around for some time. This is
3523 important because if we don't try all hosts, the address will never time
3524 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
3525
3526 if ((rc == DEFER || some_deferred) && nexthost != NULL)
3527 {
3528 BOOL timedout;
3529 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
3530
3531 if (retry != NULL && retry->rules != NULL)
3532 {
3533 retry_rule *last_rule;
3534 for (last_rule = retry->rules;
3535 last_rule->next != NULL;
3536 last_rule = last_rule->next);
3537 timedout = time(NULL) - received_time > last_rule->timeout;
3538 }
3539 else timedout = TRUE; /* No rule => timed out */
3540
3541 if (timedout)
3542 {
3543 unexpired_hosts_tried--;
3544 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
3545 "hosts_max_try (message older than host's retry time)\n");
3546 }
3547 }
3548 } /* End of loop for trying multiple hosts. */
3549
3550 /* This is the end of the loop that repeats iff expired is TRUE and
3551 ob->delay_after_cutoff is FALSE. The second time round we will
3552 try those hosts that haven't been tried since the message arrived. */
3553
3554 DEBUG(D_transport)
3555 {
3556 debug_printf("all IP addresses skipped or deferred at least one address\n");
3557 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
3558 debug_printf("retrying IP addresses not tried since message arrived\n");
3559 }
3560 }
3561
3562
3563 /* Get here if all IP addresses are skipped or defer at least one address. In
3564 MUA wrapper mode, this will happen only for connection or other non-message-
3565 specific failures. Force the delivery status for all addresses to FAIL. */
3566
3567 if (mua_wrapper)
3568 {
3569 for (addr = addrlist; addr != NULL; addr = addr->next)
3570 addr->transport_return = FAIL;
3571 goto END_TRANSPORT;
3572 }
3573
3574 /* In the normal, non-wrapper case, add a standard message to each deferred
3575 address if there hasn't been an error, that is, if it hasn't actually been
3576 tried this time. The variable "expired" will be FALSE if any deliveries were
3577 actually tried, or if there was at least one host that was not expired. That
3578 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
3579 a delivery has been tried, an error code will be set, and the failing of the
3580 message is handled by the retry code later.
3581
3582 If queue_smtp is set, or this transport was called to send a subsequent message
3583 down an existing TCP/IP connection, and something caused the host not to be
3584 found, we end up here, but can detect these cases and handle them specially. */
3585
3586 for (addr = addrlist; addr != NULL; addr = addr->next)
3587 {
3588 /* If host is not NULL, it means that we stopped processing the host list
3589 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
3590 means we need to behave as if some hosts were skipped because their retry
3591 time had not come. Specifically, this prevents the address from timing out.
3592 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
3593 hosts were tried. */
3594
3595 if (host != NULL)
3596 {
3597 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
3598 {
3599 DEBUG(D_transport)
3600 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
3601 "hosts were tried\n");
3602 }
3603 else
3604 {
3605 DEBUG(D_transport)
3606 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
3607 setflag(addr, af_retry_skipped);
3608 }
3609 }
3610
3611 if (queue_smtp) /* no deliveries attempted */
3612 {
3613 addr->transport_return = DEFER;
3614 addr->basic_errno = 0;
3615 addr->message = US"SMTP delivery explicitly queued";
3616 }
3617
3618 else if (addr->transport_return == DEFER &&
3619 (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0) &&
3620 addr->message == NULL)
3621 {
3622 addr->basic_errno = ERRNO_HRETRY;
3623 if (continue_hostname != NULL)
3624 {
3625 addr->message = US"no host found for existing SMTP connection";
3626 }
3627 else if (expired)
3628 {
3629 setflag(addr, af_pass_message); /* This is not a security risk */
3630 addr->message = (ob->delay_after_cutoff)?
3631 US"retry time not reached for any host after a long failure period" :
3632 US"all hosts have been failing for a long time and were last tried "
3633 "after this message arrived";
3634
3635 /* If we are already using fallback hosts, or there are no fallback hosts
3636 defined, convert the result to FAIL to cause a bounce. */
3637
3638 if (addr->host_list == addr->fallback_hosts ||
3639 addr->fallback_hosts == NULL)
3640 addr->transport_return = FAIL;
3641 }
3642 else
3643 {
3644 if (hosts_retry == hosts_total)
3645 addr->message = US"retry time not reached for any host";
3646 else if (hosts_fail == hosts_total)
3647 addr->message = US"all host address lookups failed permanently";
3648 else if (hosts_defer == hosts_total)
3649 addr->message = US"all host address lookups failed temporarily";
3650 else if (hosts_serial == hosts_total)
3651 addr->message = US"connection limit reached for all hosts";
3652 else if (hosts_fail+hosts_defer == hosts_total)
3653 addr->message = US"all host address lookups failed";
3654 else addr->message = US"some host address lookups failed and retry time "
3655 "not reached for other hosts or connection limit reached";
3656 }
3657 }
3658 }
3659
3660 /* Update the database which keeps information about which messages are waiting
3661 for which hosts to become available. For some message-specific errors, the
3662 update_waiting flag is turned off because we don't want follow-on deliveries in
3663 those cases. If this transport instance is explicitly limited to one message
3664 per connection then follow-on deliveries are not possible and there's no need
3665 to create/update the per-transport wait-<transport_name> database. */
3666
3667 if (update_waiting && tblock->connection_max_messages != 1)
3668 transport_update_waiting(hostlist, tblock->name);
3669
3670 END_TRANSPORT:
3671
3672 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
3673
3674 return TRUE; /* Each address has its status */
3675 }
3676
3677 /* vi: aw ai sw=2
3678 */
3679 /* End of transport/smtp.c */
Unnamed repository; edit this file 'description' to name the repository.