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On callout avoid SIZE every time but noncacheable rcpt main-verify. Bug 2151
[exim.git] / src / src / transports / smtp.c
1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
4
5 /* Copyright (c) University of Cambridge 1995 - 2017 */
6 /* See the file NOTICE for conditions of use and distribution. */
7
8 #include "../exim.h"
9 #include "smtp.h"
10
11
12 /* Options specific to the smtp transport. This transport also supports LMTP
13 over TCP/IP. The options must be in alphabetic order (note that "_" comes
14 before the lower case letters). Some live in the transport_instance block so as
15 to be publicly visible; these are flagged with opt_public. */
16
17 optionlist smtp_transport_options[] = {
18 { "*expand_multi_domain", opt_stringptr | opt_hidden | opt_public,
19 (void *)offsetof(transport_instance, expand_multi_domain) },
20 { "*expand_retry_include_ip_address", opt_stringptr | opt_hidden,
21 (void *)(offsetof(smtp_transport_options_block, expand_retry_include_ip_address)) },
22
23 { "address_retry_include_sender", opt_bool,
24 (void *)offsetof(smtp_transport_options_block, address_retry_include_sender) },
25 { "allow_localhost", opt_bool,
26 (void *)offsetof(smtp_transport_options_block, allow_localhost) },
27 { "authenticated_sender", opt_stringptr,
28 (void *)offsetof(smtp_transport_options_block, authenticated_sender) },
29 { "authenticated_sender_force", opt_bool,
30 (void *)offsetof(smtp_transport_options_block, authenticated_sender_force) },
31 { "command_timeout", opt_time,
32 (void *)offsetof(smtp_transport_options_block, command_timeout) },
33 { "connect_timeout", opt_time,
34 (void *)offsetof(smtp_transport_options_block, connect_timeout) },
35 { "connection_max_messages", opt_int | opt_public,
36 (void *)offsetof(transport_instance, connection_max_messages) },
37 { "data_timeout", opt_time,
38 (void *)offsetof(smtp_transport_options_block, data_timeout) },
39 { "delay_after_cutoff", opt_bool,
40 (void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
41 #ifndef DISABLE_DKIM
42 { "dkim_canon", opt_stringptr,
43 (void *)offsetof(smtp_transport_options_block, dkim.dkim_canon) },
44 { "dkim_domain", opt_stringptr,
45 (void *)offsetof(smtp_transport_options_block, dkim.dkim_domain) },
46 { "dkim_private_key", opt_stringptr,
47 (void *)offsetof(smtp_transport_options_block, dkim.dkim_private_key) },
48 { "dkim_selector", opt_stringptr,
49 (void *)offsetof(smtp_transport_options_block, dkim.dkim_selector) },
50 { "dkim_sign_headers", opt_stringptr,
51 (void *)offsetof(smtp_transport_options_block, dkim.dkim_sign_headers) },
52 { "dkim_strict", opt_stringptr,
53 (void *)offsetof(smtp_transport_options_block, dkim.dkim_strict) },
54 #endif
55 { "dns_qualify_single", opt_bool,
56 (void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
57 { "dns_search_parents", opt_bool,
58 (void *)offsetof(smtp_transport_options_block, dns_search_parents) },
59 { "dnssec_request_domains", opt_stringptr,
60 (void *)offsetof(smtp_transport_options_block, dnssec.request) },
61 { "dnssec_require_domains", opt_stringptr,
62 (void *)offsetof(smtp_transport_options_block, dnssec.require) },
63 { "dscp", opt_stringptr,
64 (void *)offsetof(smtp_transport_options_block, dscp) },
65 { "fallback_hosts", opt_stringptr,
66 (void *)offsetof(smtp_transport_options_block, fallback_hosts) },
67 { "final_timeout", opt_time,
68 (void *)offsetof(smtp_transport_options_block, final_timeout) },
69 { "gethostbyname", opt_bool,
70 (void *)offsetof(smtp_transport_options_block, gethostbyname) },
71 { "helo_data", opt_stringptr,
72 (void *)offsetof(smtp_transport_options_block, helo_data) },
73 { "hosts", opt_stringptr,
74 (void *)offsetof(smtp_transport_options_block, hosts) },
75 { "hosts_avoid_esmtp", opt_stringptr,
76 (void *)offsetof(smtp_transport_options_block, hosts_avoid_esmtp) },
77 { "hosts_avoid_pipelining", opt_stringptr,
78 (void *)offsetof(smtp_transport_options_block, hosts_avoid_pipelining) },
79 #ifdef SUPPORT_TLS
80 { "hosts_avoid_tls", opt_stringptr,
81 (void *)offsetof(smtp_transport_options_block, hosts_avoid_tls) },
82 #endif
83 { "hosts_max_try", opt_int,
84 (void *)offsetof(smtp_transport_options_block, hosts_max_try) },
85 { "hosts_max_try_hardlimit", opt_int,
86 (void *)offsetof(smtp_transport_options_block, hosts_max_try_hardlimit) },
87 #ifdef SUPPORT_TLS
88 { "hosts_nopass_tls", opt_stringptr,
89 (void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
90 { "hosts_noproxy_tls", opt_stringptr,
91 (void *)offsetof(smtp_transport_options_block, hosts_noproxy_tls) },
92 #endif
93 { "hosts_override", opt_bool,
94 (void *)offsetof(smtp_transport_options_block, hosts_override) },
95 { "hosts_randomize", opt_bool,
96 (void *)offsetof(smtp_transport_options_block, hosts_randomize) },
97 #if defined(SUPPORT_TLS) && !defined(DISABLE_OCSP)
98 { "hosts_request_ocsp", opt_stringptr,
99 (void *)offsetof(smtp_transport_options_block, hosts_request_ocsp) },
100 #endif
101 { "hosts_require_auth", opt_stringptr,
102 (void *)offsetof(smtp_transport_options_block, hosts_require_auth) },
103 #ifdef SUPPORT_TLS
104 # ifdef EXPERIMENTAL_DANE
105 { "hosts_require_dane", opt_stringptr,
106 (void *)offsetof(smtp_transport_options_block, hosts_require_dane) },
107 # endif
108 # ifndef DISABLE_OCSP
109 { "hosts_require_ocsp", opt_stringptr,
110 (void *)offsetof(smtp_transport_options_block, hosts_require_ocsp) },
111 # endif
112 { "hosts_require_tls", opt_stringptr,
113 (void *)offsetof(smtp_transport_options_block, hosts_require_tls) },
114 #endif
115 { "hosts_try_auth", opt_stringptr,
116 (void *)offsetof(smtp_transport_options_block, hosts_try_auth) },
117 { "hosts_try_chunking", opt_stringptr,
118 (void *)offsetof(smtp_transport_options_block, hosts_try_chunking) },
119 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
120 { "hosts_try_dane", opt_stringptr,
121 (void *)offsetof(smtp_transport_options_block, hosts_try_dane) },
122 #endif
123 { "hosts_try_fastopen", opt_stringptr,
124 (void *)offsetof(smtp_transport_options_block, hosts_try_fastopen) },
125 #ifndef DISABLE_PRDR
126 { "hosts_try_prdr", opt_stringptr,
127 (void *)offsetof(smtp_transport_options_block, hosts_try_prdr) },
128 #endif
129 #ifdef SUPPORT_TLS
130 { "hosts_verify_avoid_tls", opt_stringptr,
131 (void *)offsetof(smtp_transport_options_block, hosts_verify_avoid_tls) },
132 #endif
133 { "interface", opt_stringptr,
134 (void *)offsetof(smtp_transport_options_block, interface) },
135 { "keepalive", opt_bool,
136 (void *)offsetof(smtp_transport_options_block, keepalive) },
137 { "lmtp_ignore_quota", opt_bool,
138 (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
139 { "max_rcpt", opt_int | opt_public,
140 (void *)offsetof(transport_instance, max_addresses) },
141 { "multi_domain", opt_expand_bool | opt_public,
142 (void *)offsetof(transport_instance, multi_domain) },
143 { "port", opt_stringptr,
144 (void *)offsetof(smtp_transport_options_block, port) },
145 { "protocol", opt_stringptr,
146 (void *)offsetof(smtp_transport_options_block, protocol) },
147 { "retry_include_ip_address", opt_expand_bool,
148 (void *)offsetof(smtp_transport_options_block, retry_include_ip_address) },
149 { "serialize_hosts", opt_stringptr,
150 (void *)offsetof(smtp_transport_options_block, serialize_hosts) },
151 { "size_addition", opt_int,
152 (void *)offsetof(smtp_transport_options_block, size_addition) }
153 #ifdef SUPPORT_SOCKS
154 ,{ "socks_proxy", opt_stringptr,
155 (void *)offsetof(smtp_transport_options_block, socks_proxy) }
156 #endif
157 #ifdef SUPPORT_TLS
158 ,{ "tls_certificate", opt_stringptr,
159 (void *)offsetof(smtp_transport_options_block, tls_certificate) },
160 { "tls_crl", opt_stringptr,
161 (void *)offsetof(smtp_transport_options_block, tls_crl) },
162 { "tls_dh_min_bits", opt_int,
163 (void *)offsetof(smtp_transport_options_block, tls_dh_min_bits) },
164 { "tls_privatekey", opt_stringptr,
165 (void *)offsetof(smtp_transport_options_block, tls_privatekey) },
166 { "tls_require_ciphers", opt_stringptr,
167 (void *)offsetof(smtp_transport_options_block, tls_require_ciphers) },
168 { "tls_sni", opt_stringptr,
169 (void *)offsetof(smtp_transport_options_block, tls_sni) },
170 { "tls_tempfail_tryclear", opt_bool,
171 (void *)offsetof(smtp_transport_options_block, tls_tempfail_tryclear) },
172 { "tls_try_verify_hosts", opt_stringptr,
173 (void *)offsetof(smtp_transport_options_block, tls_try_verify_hosts) },
174 { "tls_verify_cert_hostnames", opt_stringptr,
175 (void *)offsetof(smtp_transport_options_block,tls_verify_cert_hostnames)},
176 { "tls_verify_certificates", opt_stringptr,
177 (void *)offsetof(smtp_transport_options_block, tls_verify_certificates) },
178 { "tls_verify_hosts", opt_stringptr,
179 (void *)offsetof(smtp_transport_options_block, tls_verify_hosts) }
180 #endif
181 };
182
183 /* Size of the options list. An extern variable has to be used so that its
184 address can appear in the tables drtables.c. */
185
186 int smtp_transport_options_count =
187 sizeof(smtp_transport_options)/sizeof(optionlist);
188
189
190 #ifdef MACRO_PREDEF
191
192 /* Dummy values */
193 smtp_transport_options_block smtp_transport_option_defaults = {0};
194 void smtp_transport_init(transport_instance *tblock) {}
195 BOOL smtp_transport_entry(transport_instance *tblock, address_item *addr) {return FALSE;}
196 void smtp_transport_closedown(transport_instance *tblock) {}
197
198 #else /*!MACRO_PREDEF*/
199
200
201 /* Default private options block for the smtp transport. */
202
203 smtp_transport_options_block smtp_transport_option_defaults = {
204 NULL, /* hosts */
205 NULL, /* fallback_hosts */
206 NULL, /* hostlist */
207 NULL, /* fallback_hostlist */
208 NULL, /* authenticated_sender */
209 US"$primary_hostname", /* helo_data */
210 NULL, /* interface */
211 NULL, /* port */
212 US"smtp", /* protocol */
213 NULL, /* DSCP */
214 NULL, /* serialize_hosts */
215 NULL, /* hosts_try_auth */
216 NULL, /* hosts_require_auth */
217 US"*", /* hosts_try_chunking */
218 #ifdef EXPERIMENTAL_DANE
219 NULL, /* hosts_try_dane */
220 NULL, /* hosts_require_dane */
221 #endif
222 NULL, /* hosts_try_fastopen */
223 #ifndef DISABLE_PRDR
224 US"*", /* hosts_try_prdr */
225 #endif
226 #ifndef DISABLE_OCSP
227 US"*", /* hosts_request_ocsp (except under DANE; tls_client_start()) */
228 NULL, /* hosts_require_ocsp */
229 #endif
230 NULL, /* hosts_require_tls */
231 NULL, /* hosts_avoid_tls */
232 NULL, /* hosts_verify_avoid_tls */
233 NULL, /* hosts_avoid_pipelining */
234 NULL, /* hosts_avoid_esmtp */
235 #ifdef SUPPORT_TLS
236 NULL, /* hosts_nopass_tls */
237 US"*", /* hosts_noproxy_tls */
238 #endif
239 5*60, /* command_timeout */
240 5*60, /* connect_timeout; shorter system default overrides */
241 5*60, /* data timeout */
242 10*60, /* final timeout */
243 1024, /* size_addition */
244 5, /* hosts_max_try */
245 50, /* hosts_max_try_hardlimit */
246 TRUE, /* address_retry_include_sender */
247 FALSE, /* allow_localhost */
248 FALSE, /* authenticated_sender_force */
249 FALSE, /* gethostbyname */
250 TRUE, /* dns_qualify_single */
251 FALSE, /* dns_search_parents */
252 { NULL, NULL }, /* dnssec_domains {request,require} */
253 TRUE, /* delay_after_cutoff */
254 FALSE, /* hosts_override */
255 FALSE, /* hosts_randomize */
256 TRUE, /* keepalive */
257 FALSE, /* lmtp_ignore_quota */
258 NULL, /* expand_retry_include_ip_address */
259 TRUE /* retry_include_ip_address */
260 #ifdef SUPPORT_SOCKS
261 ,NULL /* socks_proxy */
262 #endif
263 #ifdef SUPPORT_TLS
264 ,NULL, /* tls_certificate */
265 NULL, /* tls_crl */
266 NULL, /* tls_privatekey */
267 NULL, /* tls_require_ciphers */
268 NULL, /* tls_sni */
269 US"system", /* tls_verify_certificates */
270 EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
271 /* tls_dh_min_bits */
272 TRUE, /* tls_tempfail_tryclear */
273 NULL, /* tls_verify_hosts */
274 US"*", /* tls_try_verify_hosts */
275 US"*" /* tls_verify_cert_hostnames */
276 #endif
277 #ifndef DISABLE_DKIM
278 , {NULL, /* dkim_canon */
279 NULL, /* dkim_domain */
280 NULL, /* dkim_private_key */
281 NULL, /* dkim_selector */
282 NULL, /* dkim_sign_headers */
283 NULL, /* dkim_strict */
284 FALSE} /* dot_stuffed */
285 #endif
286 };
287
288 /* some DSN flags for use later */
289
290 static int rf_list[] = {rf_notify_never, rf_notify_success,
291 rf_notify_failure, rf_notify_delay };
292
293 static uschar *rf_names[] = { US"NEVER", US"SUCCESS", US"FAILURE", US"DELAY" };
294
295
296
297 /* Local statics */
298
299 static uschar *smtp_command; /* Points to last cmd for error messages */
300 static uschar *mail_command; /* Points to MAIL cmd for error messages */
301 static uschar *data_command = US""; /* Points to DATA cmd for error messages */
302 static BOOL update_waiting; /* TRUE to update the "wait" database */
303
304 /*XXX move to smtp_context */
305 static BOOL pipelining_active; /* current transaction is in pipe mode */
306
307
308 /*************************************************
309 * Setup entry point *
310 *************************************************/
311
312 /* This function is called when the transport is about to be used,
313 but before running it in a sub-process. It is used for two things:
314
315 (1) To set the fallback host list in addresses, when delivering.
316 (2) To pass back the interface, port, protocol, and other options, for use
317 during callout verification.
318
319 Arguments:
320 tblock pointer to the transport instance block
321 addrlist list of addresses about to be transported
322 tf if not NULL, pointer to block in which to return options
323 uid the uid that will be set (not used)
324 gid the gid that will be set (not used)
325 errmsg place for error message (not used)
326
327 Returns: OK always (FAIL, DEFER not used)
328 */
329
330 static int
331 smtp_transport_setup(transport_instance *tblock, address_item *addrlist,
332 transport_feedback *tf, uid_t uid, gid_t gid, uschar **errmsg)
333 {
334 smtp_transport_options_block *ob =
335 (smtp_transport_options_block *)(tblock->options_block);
336
337 errmsg = errmsg; /* Keep picky compilers happy */
338 uid = uid;
339 gid = gid;
340
341 /* Pass back options if required. This interface is getting very messy. */
342
343 if (tf)
344 {
345 tf->interface = ob->interface;
346 tf->port = ob->port;
347 tf->protocol = ob->protocol;
348 tf->hosts = ob->hosts;
349 tf->hosts_override = ob->hosts_override;
350 tf->hosts_randomize = ob->hosts_randomize;
351 tf->gethostbyname = ob->gethostbyname;
352 tf->qualify_single = ob->dns_qualify_single;
353 tf->search_parents = ob->dns_search_parents;
354 tf->helo_data = ob->helo_data;
355 }
356
357 /* Set the fallback host list for all the addresses that don't have fallback
358 host lists, provided that the local host wasn't present in the original host
359 list. */
360
361 if (!testflag(addrlist, af_local_host_removed))
362 for (; addrlist; addrlist = addrlist->next)
363 if (!addrlist->fallback_hosts) addrlist->fallback_hosts = ob->fallback_hostlist;
364
365 return OK;
366 }
367
368
369
370 /*************************************************
371 * Initialization entry point *
372 *************************************************/
373
374 /* Called for each instance, after its options have been read, to
375 enable consistency checks to be done, or anything else that needs
376 to be set up.
377
378 Argument: pointer to the transport instance block
379 Returns: nothing
380 */
381
382 void
383 smtp_transport_init(transport_instance *tblock)
384 {
385 smtp_transport_options_block *ob =
386 (smtp_transport_options_block *)(tblock->options_block);
387
388 /* Retry_use_local_part defaults FALSE if unset */
389
390 if (tblock->retry_use_local_part == TRUE_UNSET)
391 tblock->retry_use_local_part = FALSE;
392
393 /* Set the default port according to the protocol */
394
395 if (ob->port == NULL)
396 ob->port = (strcmpic(ob->protocol, US"lmtp") == 0)? US"lmtp" :
397 (strcmpic(ob->protocol, US"smtps") == 0)? US"smtps" : US"smtp";
398
399 /* Set up the setup entry point, to be called before subprocesses for this
400 transport. */
401
402 tblock->setup = smtp_transport_setup;
403
404 /* Complain if any of the timeouts are zero. */
405
406 if (ob->command_timeout <= 0 || ob->data_timeout <= 0 ||
407 ob->final_timeout <= 0)
408 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
409 "command, data, or final timeout value is zero for %s transport",
410 tblock->name);
411
412 /* If hosts_override is set and there are local hosts, set the global
413 flag that stops verify from showing router hosts. */
414
415 if (ob->hosts_override && ob->hosts != NULL) tblock->overrides_hosts = TRUE;
416
417 /* If there are any fallback hosts listed, build a chain of host items
418 for them, but do not do any lookups at this time. */
419
420 host_build_hostlist(&(ob->fallback_hostlist), ob->fallback_hosts, FALSE);
421 }
422
423
424
425
426
427 /*************************************************
428 * Set delivery info into all active addresses *
429 *************************************************/
430
431 /* Only addresses whose status is >= PENDING are relevant. A lesser
432 status means that an address is not currently being processed.
433
434 Arguments:
435 addrlist points to a chain of addresses
436 errno_value to put in each address's errno field
437 msg to put in each address's message field
438 rc to put in each address's transport_return field
439 pass_message if TRUE, set the "pass message" flag in the address
440 host if set, mark addrs as having used this host
441 smtp_greeting from peer
442 helo_response from peer
443
444 If errno_value has the special value ERRNO_CONNECTTIMEOUT, ETIMEDOUT is put in
445 the errno field, and RTEF_CTOUT is ORed into the more_errno field, to indicate
446 this particular type of timeout.
447
448 Returns: nothing
449 */
450
451 static void
452 set_errno(address_item *addrlist, int errno_value, uschar *msg, int rc,
453 BOOL pass_message, host_item * host
454 #ifdef EXPERIMENTAL_DSN_INFO
455 , const uschar * smtp_greeting, const uschar * helo_response
456 #endif
457 )
458 {
459 address_item *addr;
460 int orvalue = 0;
461 if (errno_value == ERRNO_CONNECTTIMEOUT)
462 {
463 errno_value = ETIMEDOUT;
464 orvalue = RTEF_CTOUT;
465 }
466 for (addr = addrlist; addr; addr = addr->next)
467 if (addr->transport_return >= PENDING)
468 {
469 addr->basic_errno = errno_value;
470 addr->more_errno |= orvalue;
471 if (msg)
472 {
473 addr->message = msg;
474 if (pass_message) setflag(addr, af_pass_message);
475 }
476 addr->transport_return = rc;
477 if (host)
478 {
479 addr->host_used = host;
480 #ifdef EXPERIMENTAL_DSN_INFO
481 if (smtp_greeting)
482 {uschar * s = Ustrchr(smtp_greeting, '\n'); if (s) *s = '\0';}
483 addr->smtp_greeting = smtp_greeting;
484
485 if (helo_response)
486 {uschar * s = Ustrchr(helo_response, '\n'); if (s) *s = '\0';}
487 addr->helo_response = helo_response;
488 #endif
489 }
490 }
491 }
492
493 static void
494 set_errno_nohost(address_item *addrlist, int errno_value, uschar *msg, int rc,
495 BOOL pass_message)
496 {
497 set_errno(addrlist, errno_value, msg, rc, pass_message, NULL
498 #ifdef EXPERIMENTAL_DSN_INFO
499 , NULL, NULL
500 #endif
501 );
502 }
503
504
505 /*************************************************
506 * Check an SMTP response *
507 *************************************************/
508
509 /* This function is given an errno code and the SMTP response buffer
510 to analyse, together with the host identification for generating messages. It
511 sets an appropriate message and puts the first digit of the response code into
512 the yield variable. If no response was actually read, a suitable digit is
513 chosen.
514
515 Arguments:
516 host the current host, to get its name for messages
517 errno_value pointer to the errno value
518 more_errno from the top address for use with ERRNO_FILTER_FAIL
519 buffer the SMTP response buffer
520 yield where to put a one-digit SMTP response code
521 message where to put an error message
522 pass_message set TRUE if message is an SMTP response
523
524 Returns: TRUE if an SMTP "QUIT" command should be sent, else FALSE
525 */
526
527 static BOOL
528 check_response(host_item *host, int *errno_value, int more_errno,
529 uschar *buffer, int *yield, uschar **message, BOOL *pass_message)
530 {
531 uschar * pl = pipelining_active ? US"pipelined " : US"";
532 const uschar * s;
533
534 *yield = '4'; /* Default setting is to give a temporary error */
535
536 switch(*errno_value)
537 {
538 case ETIMEDOUT: /* Handle response timeout */
539 *message = US string_sprintf("SMTP timeout after %s%s",
540 pl, smtp_command);
541 if (transport_count > 0)
542 *message = US string_sprintf("%s (%d bytes written)", *message,
543 transport_count);
544 return FALSE;
545
546 case ERRNO_SMTPFORMAT: /* Handle malformed SMTP response */
547 s = string_printing(buffer);
548 while (isspace(*s)) s++;
549 *message = *s == 0
550 ? string_sprintf("Malformed SMTP reply (an empty line) "
551 "in response to %s%s", pl, smtp_command)
552 : string_sprintf("Malformed SMTP reply in response to %s%s: %s",
553 pl, smtp_command, s);
554 return FALSE;
555
556 case ERRNO_FILTER_FAIL: /* Handle a failed filter process error;
557 can't send QUIT as we mustn't end the DATA. */
558 *message = string_sprintf("transport filter process failed (%d)%s",
559 more_errno,
560 more_errno == EX_EXECFAILED ? ": unable to execute command" : "");
561 return FALSE;
562
563 case ERRNO_CHHEADER_FAIL: /* Handle a failed add_headers expansion;
564 can't send QUIT as we mustn't end the DATA. */
565 *message =
566 string_sprintf("failed to expand headers_add or headers_remove: %s",
567 expand_string_message);
568 return FALSE;
569
570 case ERRNO_WRITEINCOMPLETE: /* failure to write a complete data block */
571 *message = string_sprintf("failed to write a data block");
572 return FALSE;
573
574 #ifdef SUPPORT_I18N
575 case ERRNO_UTF8_FWD: /* no advertised SMTPUTF8, for international message */
576 *message = US"utf8 support required but not offered for forwarding";
577 DEBUG(D_deliver|D_transport) debug_printf("%s\n", *message);
578 return TRUE;
579 #endif
580 }
581
582 /* Handle error responses from the remote mailer. */
583
584 if (buffer[0] != 0)
585 {
586 *message = string_sprintf("SMTP error from remote mail server after %s%s: "
587 "%s", pl, smtp_command, s = string_printing(buffer));
588 *pass_message = TRUE;
589 *yield = buffer[0];
590 return TRUE;
591 }
592
593 /* No data was read. If there is no errno, this must be the EOF (i.e.
594 connection closed) case, which causes deferral. An explicit connection reset
595 error has the same effect. Otherwise, put the host's identity in the message,
596 leaving the errno value to be interpreted as well. In all cases, we have to
597 assume the connection is now dead. */
598
599 if (*errno_value == 0 || *errno_value == ECONNRESET)
600 {
601 *errno_value = ERRNO_SMTPCLOSED;
602 *message = US string_sprintf("Remote host closed connection "
603 "in response to %s%s", pl, smtp_command);
604 }
605 else
606 *message = US string_sprintf("%s [%s]", host->name, host->address);
607
608 return FALSE;
609 }
610
611
612
613 /*************************************************
614 * Write error message to logs *
615 *************************************************/
616
617 /* This writes to the main log and to the message log.
618
619 Arguments:
620 addr the address item containing error information
621 host the current host
622
623 Returns: nothing
624 */
625
626 static void
627 write_logs(address_item *addr, host_item *host)
628 {
629 uschar * message = LOGGING(outgoing_port)
630 ? string_sprintf("H=%s [%s]:%d", host->name, host->address,
631 host->port == PORT_NONE ? 25 : host->port)
632 : string_sprintf("H=%s [%s]", host->name, host->address);
633
634 if (addr->message)
635 {
636 message = string_sprintf("%s: %s", message, addr->message);
637 if (addr->basic_errno > 0)
638 message = string_sprintf("%s: %s", message, strerror(addr->basic_errno));
639 log_write(0, LOG_MAIN, "%s", message);
640 deliver_msglog("%s %s\n", tod_stamp(tod_log), message);
641 }
642 else
643 {
644 const uschar * s = exim_errstr(addr->basic_errno);
645 log_write(0, LOG_MAIN, "%s %s", message, s);
646 deliver_msglog("%s %s %s\n", tod_stamp(tod_log), message, s);
647 }
648 }
649
650 static void
651 msglog_line(host_item * host, uschar * message)
652 {
653 deliver_msglog("%s H=%s [%s] %s\n", tod_stamp(tod_log),
654 host->name, host->address, message);
655 }
656
657
658
659 #ifndef DISABLE_EVENT
660 /*************************************************
661 * Post-defer action *
662 *************************************************/
663
664 /* This expands an arbitrary per-transport string.
665 It might, for example, be used to write to the database log.
666
667 Arguments:
668 addr the address item containing error information
669 host the current host
670
671 Returns: nothing
672 */
673
674 static void
675 deferred_event_raise(address_item *addr, host_item *host)
676 {
677 uschar * action = addr->transport->event_action;
678 const uschar * save_domain;
679 uschar * save_local;
680
681 if (!action)
682 return;
683
684 save_domain = deliver_domain;
685 save_local = deliver_localpart;
686
687 /*XXX would ip & port already be set up? */
688 deliver_host_address = string_copy(host->address);
689 deliver_host_port = host->port == PORT_NONE ? 25 : host->port;
690 event_defer_errno = addr->basic_errno;
691
692 router_name = addr->router->name;
693 transport_name = addr->transport->name;
694 deliver_domain = addr->domain;
695 deliver_localpart = addr->local_part;
696
697 (void) event_raise(action, US"msg:host:defer",
698 addr->message
699 ? addr->basic_errno > 0
700 ? string_sprintf("%s: %s", addr->message, strerror(addr->basic_errno))
701 : string_copy(addr->message)
702 : addr->basic_errno > 0
703 ? string_copy(US strerror(addr->basic_errno))
704 : NULL);
705
706 deliver_localpart = save_local;
707 deliver_domain = save_domain;
708 router_name = transport_name = NULL;
709 }
710 #endif
711
712 /*************************************************
713 * Synchronize SMTP responses *
714 *************************************************/
715
716 /* This function is called from smtp_deliver() to receive SMTP responses from
717 the server, and match them up with the commands to which they relate. When
718 PIPELINING is not in use, this function is called after every command, and is
719 therefore somewhat over-engineered, but it is simpler to use a single scheme
720 that works both with and without PIPELINING instead of having two separate sets
721 of code.
722
723 The set of commands that are buffered up with pipelining may start with MAIL
724 and may end with DATA; in between are RCPT commands that correspond to the
725 addresses whose status is PENDING_DEFER. All other commands (STARTTLS, AUTH,
726 etc.) are never buffered.
727
728 Errors after MAIL or DATA abort the whole process leaving the response in the
729 buffer. After MAIL, pending responses are flushed, and the original command is
730 re-instated in big_buffer for error messages. For RCPT commands, the remote is
731 permitted to reject some recipient addresses while accepting others. However
732 certain errors clearly abort the whole process. Set the value in
733 transport_return to PENDING_OK if the address is accepted. If there is a
734 subsequent general error, it will get reset accordingly. If not, it will get
735 converted to OK at the end.
736
737 Arguments:
738 sx smtp connection context
739 count the number of responses to read
740 pending_DATA 0 if last command sent was not DATA
741 +1 if previously had a good recipient
742 -1 if not previously had a good recipient
743
744 Returns: 3 if at least one address had 2xx and one had 5xx
745 2 if at least one address had 5xx but none had 2xx
746 1 if at least one host had a 2xx response, but none had 5xx
747 0 no address had 2xx or 5xx but no errors (all 4xx, or just DATA)
748 -1 timeout while reading RCPT response
749 -2 I/O or other non-response error for RCPT
750 -3 DATA or MAIL failed - errno and buffer set
751 */
752
753 static int
754 sync_responses(smtp_context * sx, int count, int pending_DATA)
755 {
756 address_item *addr = sx->sync_addr;
757 smtp_transport_options_block *ob =
758 (smtp_transport_options_block *)sx->tblock->options_block;
759 int yield = 0;
760
761 /* Handle the response for a MAIL command. On error, reinstate the original
762 command in big_buffer for error message use, and flush any further pending
763 responses before returning, except after I/O errors and timeouts. */
764
765 if (sx->pending_MAIL)
766 {
767 count--;
768 if (!smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
769 '2', ob->command_timeout))
770 {
771 DEBUG(D_transport) debug_printf("bad response for MAIL\n");
772 Ustrcpy(big_buffer, mail_command); /* Fits, because it came from there! */
773 if (errno == 0 && sx->buffer[0] != 0)
774 {
775 uschar flushbuffer[4096];
776 int save_errno = 0;
777 if (sx->buffer[0] == '4')
778 {
779 save_errno = ERRNO_MAIL4XX;
780 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
781 }
782 while (count-- > 0)
783 {
784 if (!smtp_read_response(&sx->inblock, flushbuffer, sizeof(flushbuffer),
785 '2', ob->command_timeout)
786 && (errno != 0 || flushbuffer[0] == 0))
787 break;
788 }
789 errno = save_errno;
790 }
791
792 if (pending_DATA) count--; /* Number of RCPT responses to come */
793 while (count-- > 0) /* Mark any pending addrs with the host used */
794 {
795 while (addr->transport_return != PENDING_DEFER) addr = addr->next;
796 addr->host_used = sx->host;
797 addr = addr->next;
798 }
799 return -3;
800 }
801 }
802
803 if (pending_DATA) count--; /* Number of RCPT responses to come */
804
805 /* Read and handle the required number of RCPT responses, matching each one up
806 with an address by scanning for the next address whose status is PENDING_DEFER.
807 */
808
809 while (count-- > 0)
810 {
811 while (addr->transport_return != PENDING_DEFER)
812 if (!(addr = addr->next))
813 return -2;
814
815 /* The address was accepted */
816 addr->host_used = sx->host;
817
818 if (smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
819 '2', ob->command_timeout))
820 {
821 yield |= 1;
822 addr->transport_return = PENDING_OK;
823
824 /* If af_dr_retry_exists is set, there was a routing delay on this address;
825 ensure that any address-specific retry record is expunged. We do this both
826 for the basic key and for the version that also includes the sender. */
827
828 if (testflag(addr, af_dr_retry_exists))
829 {
830 uschar *altkey = string_sprintf("%s:<%s>", addr->address_retry_key,
831 sender_address);
832 retry_add_item(addr, altkey, rf_delete);
833 retry_add_item(addr, addr->address_retry_key, rf_delete);
834 }
835 }
836
837 /* Timeout while reading the response */
838
839 else if (errno == ETIMEDOUT)
840 {
841 uschar *message = string_sprintf("SMTP timeout after RCPT TO:<%s>",
842 transport_rcpt_address(addr, sx->tblock->rcpt_include_affixes));
843 set_errno_nohost(sx->first_addr, ETIMEDOUT, message, DEFER, FALSE);
844 retry_add_item(addr, addr->address_retry_key, 0);
845 update_waiting = FALSE;
846 return -1;
847 }
848
849 /* Handle other errors in obtaining an SMTP response by returning -1. This
850 will cause all the addresses to be deferred. Restore the SMTP command in
851 big_buffer for which we are checking the response, so the error message
852 makes sense. */
853
854 else if (errno != 0 || sx->buffer[0] == 0)
855 {
856 string_format(big_buffer, big_buffer_size, "RCPT TO:<%s>",
857 transport_rcpt_address(addr, sx->tblock->rcpt_include_affixes));
858 return -2;
859 }
860
861 /* Handle SMTP permanent and temporary response codes. */
862
863 else
864 {
865 addr->message =
866 string_sprintf("SMTP error from remote mail server after RCPT TO:<%s>: "
867 "%s", transport_rcpt_address(addr, sx->tblock->rcpt_include_affixes),
868 string_printing(sx->buffer));
869 setflag(addr, af_pass_message);
870 if (!sx->verify)
871 msglog_line(sx->host, addr->message);
872
873 /* The response was 5xx */
874
875 if (sx->buffer[0] == '5')
876 {
877 addr->transport_return = FAIL;
878 yield |= 2;
879 }
880
881 /* The response was 4xx */
882
883 else
884 {
885 addr->transport_return = DEFER;
886 addr->basic_errno = ERRNO_RCPT4XX;
887 addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
888
889 if (!sx->verify)
890 {
891 #ifndef DISABLE_EVENT
892 event_defer_errno = addr->more_errno;
893 msg_event_raise(US"msg:rcpt:host:defer", addr);
894 #endif
895
896 /* Log temporary errors if there are more hosts to be tried.
897 If not, log this last one in the == line. */
898
899 if (sx->host->next)
900 log_write(0, LOG_MAIN, "H=%s [%s]: %s",
901 sx->host->name, sx->host->address, addr->message);
902
903 #ifndef DISABLE_EVENT
904 else
905 msg_event_raise(US"msg:rcpt:defer", addr);
906 #endif
907
908 /* Do not put this message on the list of those waiting for specific
909 hosts, as otherwise it is likely to be tried too often. */
910
911 update_waiting = FALSE;
912
913 /* Add a retry item for the address so that it doesn't get tried again
914 too soon. If address_retry_include_sender is true, add the sender address
915 to the retry key. */
916
917 retry_add_item(addr,
918 ob->address_retry_include_sender
919 ? string_sprintf("%s:<%s>", addr->address_retry_key, sender_address)
920 : addr->address_retry_key,
921 0);
922 }
923 }
924 }
925 } /* Loop for next RCPT response */
926
927 /* Update where to start at for the next block of responses, unless we
928 have already handled all the addresses. */
929
930 if (addr) sx->sync_addr = addr->next;
931
932 /* Handle a response to DATA. If we have not had any good recipients, either
933 previously or in this block, the response is ignored. */
934
935 if (pending_DATA != 0 &&
936 !smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
937 '3', ob->command_timeout))
938 {
939 int code;
940 uschar *msg;
941 BOOL pass_message;
942 if (pending_DATA > 0 || (yield & 1) != 0)
943 {
944 if (errno == 0 && sx->buffer[0] == '4')
945 {
946 errno = ERRNO_DATA4XX;
947 sx->first_addr->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
948 }
949 return -3;
950 }
951 (void)check_response(sx->host, &errno, 0, sx->buffer, &code, &msg, &pass_message);
952 DEBUG(D_transport) debug_printf("%s\nerror for DATA ignored: pipelining "
953 "is in use and there were no good recipients\n", msg);
954 }
955
956 /* All responses read and handled; MAIL (if present) received 2xx and DATA (if
957 present) received 3xx. If any RCPTs were handled and yielded anything other
958 than 4xx, yield will be set non-zero. */
959
960 return yield;
961 }
962
963
964
965 /* Do the client side of smtp-level authentication */
966 /*
967 Arguments:
968 buffer EHLO response from server (gets overwritten)
969 addrlist chain of potential addresses to deliver
970 host host to deliver to
971 ob transport options
972 ibp, obp comms channel control blocks
973
974 Returns:
975 OK Success, or failed (but not required): global "smtp_authenticated" set
976 DEFER Failed authentication (and was required)
977 ERROR Internal problem
978
979 FAIL_SEND Failed communications - transmit
980 FAIL - response
981 */
982
983 int
984 smtp_auth(uschar *buffer, unsigned bufsize, address_item *addrlist, host_item *host,
985 smtp_transport_options_block *ob, BOOL is_esmtp,
986 smtp_inblock *ibp, smtp_outblock *obp)
987 {
988 int require_auth;
989 uschar *fail_reason = US"server did not advertise AUTH support";
990
991 smtp_authenticated = FALSE;
992 client_authenticator = client_authenticated_id = client_authenticated_sender = NULL;
993 require_auth = verify_check_given_host(&ob->hosts_require_auth, host);
994
995 if (is_esmtp && !regex_AUTH) regex_AUTH =
996 regex_must_compile(US"\\n250[\\s\\-]AUTH\\s+([\\-\\w\\s]+)(?:\\n|$)",
997 FALSE, TRUE);
998
999 if (is_esmtp && regex_match_and_setup(regex_AUTH, buffer, 0, -1))
1000 {
1001 uschar *names = string_copyn(expand_nstring[1], expand_nlength[1]);
1002 expand_nmax = -1; /* reset */
1003
1004 /* Must not do this check until after we have saved the result of the
1005 regex match above. */
1006
1007 if (require_auth == OK ||
1008 verify_check_given_host(&ob->hosts_try_auth, host) == OK)
1009 {
1010 auth_instance *au;
1011 fail_reason = US"no common mechanisms were found";
1012
1013 DEBUG(D_transport) debug_printf("scanning authentication mechanisms\n");
1014
1015 /* Scan the configured authenticators looking for one which is configured
1016 for use as a client, which is not suppressed by client_condition, and
1017 whose name matches an authentication mechanism supported by the server.
1018 If one is found, attempt to authenticate by calling its client function.
1019 */
1020
1021 for (au = auths; !smtp_authenticated && au != NULL; au = au->next)
1022 {
1023 uschar *p = names;
1024 if (!au->client ||
1025 (au->client_condition != NULL &&
1026 !expand_check_condition(au->client_condition, au->name,
1027 US"client authenticator")))
1028 {
1029 DEBUG(D_transport) debug_printf("skipping %s authenticator: %s\n",
1030 au->name,
1031 (au->client)? "client_condition is false" :
1032 "not configured as a client");
1033 continue;
1034 }
1035
1036 /* Loop to scan supported server mechanisms */
1037
1038 while (*p != 0)
1039 {
1040 int rc;
1041 int len = Ustrlen(au->public_name);
1042 while (isspace(*p)) p++;
1043
1044 if (strncmpic(au->public_name, p, len) != 0 ||
1045 (p[len] != 0 && !isspace(p[len])))
1046 {
1047 while (*p != 0 && !isspace(*p)) p++;
1048 continue;
1049 }
1050
1051 /* Found data for a listed mechanism. Call its client entry. Set
1052 a flag in the outblock so that data is overwritten after sending so
1053 that reflections don't show it. */
1054
1055 fail_reason = US"authentication attempt(s) failed";
1056 obp->authenticating = TRUE;
1057 rc = (au->info->clientcode)(au, ibp, obp,
1058 ob->command_timeout, buffer, bufsize);
1059 obp->authenticating = FALSE;
1060 DEBUG(D_transport) debug_printf("%s authenticator yielded %d\n",
1061 au->name, rc);
1062
1063 /* A temporary authentication failure must hold up delivery to
1064 this host. After a permanent authentication failure, we carry on
1065 to try other authentication methods. If all fail hard, try to
1066 deliver the message unauthenticated unless require_auth was set. */
1067
1068 switch(rc)
1069 {
1070 case OK:
1071 smtp_authenticated = TRUE; /* stops the outer loop */
1072 client_authenticator = au->name;
1073 if (au->set_client_id != NULL)
1074 client_authenticated_id = expand_string(au->set_client_id);
1075 break;
1076
1077 /* Failure after writing a command */
1078
1079 case FAIL_SEND:
1080 return FAIL_SEND;
1081
1082 /* Failure after reading a response */
1083
1084 case FAIL:
1085 if (errno != 0 || buffer[0] != '5') return FAIL;
1086 log_write(0, LOG_MAIN, "%s authenticator failed H=%s [%s] %s",
1087 au->name, host->name, host->address, buffer);
1088 break;
1089
1090 /* Failure by some other means. In effect, the authenticator
1091 decided it wasn't prepared to handle this case. Typically this
1092 is the result of "fail" in an expansion string. Do we need to
1093 log anything here? Feb 2006: a message is now put in the buffer
1094 if logging is required. */
1095
1096 case CANCELLED:
1097 if (*buffer != 0)
1098 log_write(0, LOG_MAIN, "%s authenticator cancelled "
1099 "authentication H=%s [%s] %s", au->name, host->name,
1100 host->address, buffer);
1101 break;
1102
1103 /* Internal problem, message in buffer. */
1104
1105 case ERROR:
1106 set_errno_nohost(addrlist, ERRNO_AUTHPROB, string_copy(buffer),
1107 DEFER, FALSE);
1108 return ERROR;
1109 }
1110
1111 break; /* If not authenticated, try next authenticator */
1112 } /* Loop for scanning supported server mechanisms */
1113 } /* Loop for further authenticators */
1114 }
1115 }
1116
1117 /* If we haven't authenticated, but are required to, give up. */
1118
1119 if (require_auth == OK && !smtp_authenticated)
1120 {
1121 set_errno_nohost(addrlist, ERRNO_AUTHFAIL,
1122 string_sprintf("authentication required but %s", fail_reason), DEFER,
1123 FALSE);
1124 return DEFER;
1125 }
1126
1127 return OK;
1128 }
1129
1130
1131 /* Construct AUTH appendix string for MAIL TO */
1132 /*
1133 Arguments
1134 buffer to build string
1135 addrlist chain of potential addresses to deliver
1136 ob transport options
1137
1138 Globals smtp_authenticated
1139 client_authenticated_sender
1140 Return True on error, otherwise buffer has (possibly empty) terminated string
1141 */
1142
1143 BOOL
1144 smtp_mail_auth_str(uschar *buffer, unsigned bufsize, address_item *addrlist,
1145 smtp_transport_options_block *ob)
1146 {
1147 uschar *local_authenticated_sender = authenticated_sender;
1148
1149 #ifdef notdef
1150 debug_printf("smtp_mail_auth_str: as<%s> os<%s> SA<%s>\n", authenticated_sender, ob->authenticated_sender, smtp_authenticated?"Y":"N");
1151 #endif
1152
1153 if (ob->authenticated_sender != NULL)
1154 {
1155 uschar *new = expand_string(ob->authenticated_sender);
1156 if (new == NULL)
1157 {
1158 if (!expand_string_forcedfail)
1159 {
1160 uschar *message = string_sprintf("failed to expand "
1161 "authenticated_sender: %s", expand_string_message);
1162 set_errno_nohost(addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1163 return TRUE;
1164 }
1165 }
1166 else if (new[0] != 0) local_authenticated_sender = new;
1167 }
1168
1169 /* Add the authenticated sender address if present */
1170
1171 if ((smtp_authenticated || ob->authenticated_sender_force) &&
1172 local_authenticated_sender != NULL)
1173 {
1174 string_format(buffer, bufsize, " AUTH=%s",
1175 auth_xtextencode(local_authenticated_sender,
1176 Ustrlen(local_authenticated_sender)));
1177 client_authenticated_sender = string_copy(local_authenticated_sender);
1178 }
1179 else
1180 *buffer= 0;
1181
1182 return FALSE;
1183 }
1184
1185
1186
1187 #ifdef EXPERIMENTAL_DANE
1188 /* Lookup TLSA record for host/port.
1189 Return: OK success with dnssec; DANE mode
1190 DEFER Do not use this host now, may retry later
1191 FAIL_FORCED No TLSA record; DANE not usable
1192 FAIL Do not use this connection
1193 */
1194
1195 int
1196 tlsa_lookup(const host_item * host, dns_answer * dnsa, BOOL dane_required)
1197 {
1198 /* move this out to host.c given the similarity to dns_lookup() ? */
1199 uschar buffer[300];
1200 const uschar * fullname = buffer;
1201 int rc;
1202 BOOL sec;
1203
1204 /* TLSA lookup string */
1205 (void)sprintf(CS buffer, "_%d._tcp.%.256s", host->port, host->name);
1206
1207 rc = dns_lookup(dnsa, buffer, T_TLSA, &fullname);
1208 sec = dns_is_secure(dnsa);
1209 DEBUG(D_transport)
1210 debug_printf("TLSA lookup ret %d %sDNSSEC\n", rc, sec ? "" : "not ");
1211
1212 switch (rc)
1213 {
1214 case DNS_SUCCEED:
1215 if (sec) return OK;
1216
1217 log_write(0, LOG_MAIN, "DANE error: TLSA lookup not DNSSEC");
1218 /*FALLTHROUGH*/
1219 case DNS_AGAIN:
1220 return DEFER; /* just defer this TLS'd conn */
1221
1222 case DNS_NODATA: /* no TLSA RR for this lookup */
1223 case DNS_NOMATCH: /* no records at all for this lookup */
1224 return dane_required ? FAIL : FAIL_FORCED;
1225
1226 default:
1227 case DNS_FAIL:
1228 return dane_required ? FAIL : DEFER;
1229 }
1230 }
1231 #endif
1232
1233
1234
1235 typedef struct smtp_compare_s
1236 {
1237 uschar *current_sender_address;
1238 struct transport_instance *tblock;
1239 } smtp_compare_t;
1240
1241
1242 /* Create a unique string that identifies this message, it is based on
1243 sender_address, helo_data and tls_certificate if enabled.
1244 */
1245
1246 static uschar *
1247 smtp_local_identity(uschar * sender, struct transport_instance * tblock)
1248 {
1249 address_item * addr1;
1250 uschar * if1 = US"";
1251 uschar * helo1 = US"";
1252 #ifdef SUPPORT_TLS
1253 uschar * tlsc1 = US"";
1254 #endif
1255 uschar * save_sender_address = sender_address;
1256 uschar * local_identity = NULL;
1257 smtp_transport_options_block * ob =
1258 (smtp_transport_options_block *)tblock->options_block;
1259
1260 sender_address = sender;
1261
1262 addr1 = deliver_make_addr (sender, TRUE);
1263 deliver_set_expansions(addr1);
1264
1265 if (ob->interface)
1266 if1 = expand_string(ob->interface);
1267
1268 if (ob->helo_data)
1269 helo1 = expand_string(ob->helo_data);
1270
1271 #ifdef SUPPORT_TLS
1272 if (ob->tls_certificate)
1273 tlsc1 = expand_string(ob->tls_certificate);
1274 local_identity = string_sprintf ("%s^%s^%s", if1, helo1, tlsc1);
1275 #else
1276 local_identity = string_sprintf ("%s^%s", if1, helo1);
1277 #endif
1278
1279 deliver_set_expansions(NULL);
1280 sender_address = save_sender_address;
1281
1282 return local_identity;
1283 }
1284
1285
1286
1287 /* This routine is a callback that is called from transport_check_waiting.
1288 This function will evaluate the incoming message versus the previous
1289 message. If the incoming message is using a different local identity then
1290 we will veto this new message. */
1291
1292 static BOOL
1293 smtp_are_same_identities(uschar * message_id, smtp_compare_t * s_compare)
1294 {
1295 uschar * message_local_identity,
1296 * current_local_identity,
1297 * new_sender_address;
1298
1299 current_local_identity =
1300 smtp_local_identity(s_compare->current_sender_address, s_compare->tblock);
1301
1302 if (!(new_sender_address = deliver_get_sender_address(message_id)))
1303 return 0;
1304
1305 message_local_identity =
1306 smtp_local_identity(new_sender_address, s_compare->tblock);
1307
1308 return Ustrcmp(current_local_identity, message_local_identity) == 0;
1309 }
1310
1311
1312
1313 static uschar
1314 ehlo_response(uschar * buf, uschar checks)
1315 {
1316 size_t bsize = Ustrlen(buf);
1317
1318 #ifdef SUPPORT_TLS
1319 if ( checks & OPTION_TLS
1320 && pcre_exec(regex_STARTTLS, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1321 checks &= ~OPTION_TLS;
1322 #endif
1323
1324 if ( checks & OPTION_IGNQ
1325 && pcre_exec(regex_IGNOREQUOTA, NULL, CS buf, bsize, 0,
1326 PCRE_EOPT, NULL, 0) < 0)
1327 checks &= ~OPTION_IGNQ;
1328
1329 if ( checks & OPTION_CHUNKING
1330 && pcre_exec(regex_CHUNKING, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1331 checks &= ~OPTION_CHUNKING;
1332
1333 #ifndef DISABLE_PRDR
1334 if ( checks & OPTION_PRDR
1335 && pcre_exec(regex_PRDR, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1336 checks &= ~OPTION_PRDR;
1337 #endif
1338
1339 #ifdef SUPPORT_I18N
1340 if ( checks & OPTION_UTF8
1341 && pcre_exec(regex_UTF8, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1342 checks &= ~OPTION_UTF8;
1343 #endif
1344
1345 if ( checks & OPTION_DSN
1346 && pcre_exec(regex_DSN, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1347 checks &= ~OPTION_DSN;
1348
1349 if ( checks & OPTION_PIPE
1350 && pcre_exec(regex_PIPELINING, NULL, CS buf, bsize, 0,
1351 PCRE_EOPT, NULL, 0) < 0)
1352 checks &= ~OPTION_PIPE;
1353
1354 if ( checks & OPTION_SIZE
1355 && pcre_exec(regex_SIZE, NULL, CS buf, bsize, 0, PCRE_EOPT, NULL, 0) < 0)
1356 checks &= ~OPTION_SIZE;
1357
1358 return checks;
1359 }
1360
1361
1362
1363 /* Callback for emitting a BDAT data chunk header.
1364
1365 If given a nonzero size, first flush any buffered SMTP commands
1366 then emit the command.
1367
1368 Reap previous SMTP command responses if requested, and always reap
1369 the response from a previous BDAT command.
1370
1371 Args:
1372 tctx transport context
1373 chunk_size value for SMTP BDAT command
1374 flags
1375 tc_chunk_last add LAST option to SMTP BDAT command
1376 tc_reap_prev reap response to previous SMTP commands
1377
1378 Returns: OK or ERROR
1379 */
1380
1381 static int
1382 smtp_chunk_cmd_callback(transport_ctx * tctx, unsigned chunk_size,
1383 unsigned flags)
1384 {
1385 smtp_transport_options_block * ob =
1386 (smtp_transport_options_block *)(tctx->tblock->options_block);
1387 smtp_context * sx = tctx->smtp_context;
1388 int cmd_count = 0;
1389 int prev_cmd_count;
1390
1391 /* Write SMTP chunk header command. If not reaping responses, note that
1392 there may be more writes (like, the chunk data) done soon. */
1393
1394 if (chunk_size > 0)
1395 {
1396 if((cmd_count = smtp_write_command(&sx->outblock,
1397 flags & tc_reap_prev ? SCMD_FLUSH : SCMD_MORE,
1398 "BDAT %u%s\r\n", chunk_size, flags & tc_chunk_last ? " LAST" : "")
1399 ) < 0) return ERROR;
1400 if (flags & tc_chunk_last)
1401 data_command = string_copy(big_buffer); /* Save for later error message */
1402 }
1403
1404 prev_cmd_count = cmd_count += sx->cmd_count;
1405
1406 /* Reap responses for any previous, but not one we just emitted */
1407
1408 if (chunk_size > 0)
1409 prev_cmd_count--;
1410 if (sx->pending_BDAT)
1411 prev_cmd_count--;
1412
1413 if (flags & tc_reap_prev && prev_cmd_count > 0)
1414 {
1415 DEBUG(D_transport) debug_printf("look for %d responses"
1416 " for previous pipelined cmds\n", prev_cmd_count);
1417
1418 switch(sync_responses(sx, prev_cmd_count, 0))
1419 {
1420 case 1: /* 2xx (only) => OK */
1421 case 3: sx->good_RCPT = TRUE; /* 2xx & 5xx => OK & progress made */
1422 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
1423 case 0: break; /* No 2xx or 5xx, but no probs */
1424
1425 case -1: /* Timeout on RCPT */
1426 default: return ERROR; /* I/O error, or any MAIL/DATA error */
1427 }
1428 cmd_count = 1;
1429 if (!sx->pending_BDAT)
1430 pipelining_active = FALSE;
1431 }
1432
1433 /* Reap response for an outstanding BDAT */
1434
1435 if (sx->pending_BDAT)
1436 {
1437 DEBUG(D_transport) debug_printf("look for one response for BDAT\n");
1438
1439 if (!smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer), '2',
1440 ob->command_timeout))
1441 {
1442 if (errno == 0 && sx->buffer[0] == '4')
1443 {
1444 errno = ERRNO_DATA4XX; /*XXX does this actually get used? */
1445 sx->addrlist->more_errno |=
1446 ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
1447 }
1448 return ERROR;
1449 }
1450 cmd_count--;
1451 sx->pending_BDAT = FALSE;
1452 pipelining_active = FALSE;
1453 }
1454 else if (chunk_size > 0)
1455 sx->pending_BDAT = TRUE;
1456
1457
1458 sx->cmd_count = cmd_count;
1459 return OK;
1460 }
1461
1462
1463
1464 /*************************************************
1465 * Make connection for given message *
1466 *************************************************/
1467
1468 /*
1469 Arguments:
1470 ctx connection context
1471 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
1472 a second attempt after TLS initialization fails
1473
1474 Returns: OK - the connection was made and the delivery attempted;
1475 fd is set in the conn context, tls_out set up.
1476 DEFER - the connection could not be made, or something failed
1477 while setting up the SMTP session, or there was a
1478 non-message-specific error, such as a timeout.
1479 ERROR - helo_data or add_headers or authenticated_sender is
1480 specified for this transport, and the string failed
1481 to expand
1482 */
1483 int
1484 smtp_setup_conn(smtp_context * sx, BOOL suppress_tls)
1485 {
1486 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1487 dns_answer tlsa_dnsa;
1488 #endif
1489 BOOL pass_message = FALSE;
1490 uschar * message = NULL;
1491 int yield = OK;
1492 int rc;
1493
1494 sx->ob = (smtp_transport_options_block *) sx->tblock->options_block;
1495
1496 sx->lmtp = strcmpic(sx->ob->protocol, US"lmtp") == 0;
1497 sx->smtps = strcmpic(sx->ob->protocol, US"smtps") == 0;
1498 sx->ok = FALSE;
1499 sx->send_rset = TRUE;
1500 sx->send_quit = TRUE;
1501 sx->setting_up = TRUE;
1502 sx->esmtp = TRUE;
1503 sx->esmtp_sent = FALSE;
1504 #ifdef SUPPORT_I18N
1505 sx->utf8_needed = FALSE;
1506 #endif
1507 sx->dsn_all_lasthop = TRUE;
1508 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1509 sx->dane = FALSE;
1510 sx->dane_required = verify_check_given_host(&sx->ob->hosts_require_dane, sx->host) == OK;
1511 #endif
1512
1513 if ((sx->max_rcpt = sx->tblock->max_addresses) == 0) sx->max_rcpt = 999999;
1514 sx->peer_offered = 0;
1515 sx->avoid_option = 0;
1516 sx->igquotstr = US"";
1517 if (!sx->helo_data) sx->helo_data = sx->ob->helo_data;
1518 #ifdef EXPERIMENTAL_DSN_INFO
1519 sx->smtp_greeting = NULL;
1520 sx->helo_response = NULL;
1521 #endif
1522
1523 smtp_command = US"initial connection";
1524 sx->buffer[0] = '\0';
1525
1526 /* Set up the buffer for reading SMTP response packets. */
1527
1528 sx->inblock.buffer = sx->inbuffer;
1529 sx->inblock.buffersize = sizeof(sx->inbuffer);
1530 sx->inblock.ptr = sx->inbuffer;
1531 sx->inblock.ptrend = sx->inbuffer;
1532
1533 /* Set up the buffer for holding SMTP commands while pipelining */
1534
1535 sx->outblock.buffer = sx->outbuffer;
1536 sx->outblock.buffersize = sizeof(sx->outbuffer);
1537 sx->outblock.ptr = sx->outbuffer;
1538 sx->outblock.cmd_count = 0;
1539 sx->outblock.authenticating = FALSE;
1540
1541 /* Reset the parameters of a TLS session. */
1542
1543 tls_out.bits = 0;
1544 tls_out.cipher = NULL; /* the one we may use for this transport */
1545 tls_out.ourcert = NULL;
1546 tls_out.peercert = NULL;
1547 tls_out.peerdn = NULL;
1548 #if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
1549 tls_out.sni = NULL;
1550 #endif
1551 tls_out.ocsp = OCSP_NOT_REQ;
1552
1553 /* Flip the legacy TLS-related variables over to the outbound set in case
1554 they're used in the context of the transport. Don't bother resetting
1555 afterward (when being used by a transport) as we're in a subprocess.
1556 For verify, unflipped once the callout is dealt with */
1557
1558 tls_modify_variables(&tls_out);
1559
1560 #ifndef SUPPORT_TLS
1561 if (sx->smtps)
1562 {
1563 set_errno_nohost(sx->addrlist, ERRNO_TLSFAILURE, US"TLS support not available",
1564 DEFER, FALSE);
1565 return ERROR;
1566 }
1567 #endif
1568
1569 /* Make a connection to the host if this isn't a continued delivery, and handle
1570 the initial interaction and HELO/EHLO/LHLO. Connect timeout errors are handled
1571 specially so they can be identified for retries. */
1572
1573 if (!continue_hostname)
1574 {
1575 if (sx->verify)
1576 HDEBUG(D_verify) debug_printf("interface=%s port=%d\n", sx->interface, sx->port);
1577
1578 /* Get the actual port the connection will use, into sx->host */
1579
1580 smtp_port_for_connect(sx->host, sx->port);
1581
1582 #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
1583 /* Do TLSA lookup for DANE */
1584 {
1585 tls_out.dane_verified = FALSE;
1586 tls_out.tlsa_usage = 0;
1587
1588 if (sx->host->dnssec == DS_YES)
1589 {
1590 if( sx->dane_required
1591 || verify_check_given_host(&sx->ob->hosts_try_dane, sx->host) == OK
1592 )
1593 switch (rc = tlsa_lookup(sx->host, &tlsa_dnsa, sx->dane_required))
1594 {
1595 case OK: sx->dane = TRUE;
1596 sx->ob->tls_tempfail_tryclear = FALSE;
1597 break;
1598 case FAIL_FORCED: break;
1599 default: set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
1600 string_sprintf("DANE error: tlsa lookup %s",
1601 rc == DEFER ? "DEFER" : "FAIL"),
1602 rc, FALSE);
1603 return rc;
1604 }
1605 }
1606 else if (sx->dane_required)
1607 {
1608 set_errno_nohost(sx->addrlist, ERRNO_DNSDEFER,
1609 string_sprintf("DANE error: %s lookup not DNSSEC", sx->host->name),
1610 FAIL, FALSE);
1611 return FAIL;
1612 }
1613 }
1614 #endif /*DANE*/
1615
1616 /* Make the TCP connection */
1617
1618 sx->inblock.sock = sx->outblock.sock =
1619 smtp_connect(sx->host, sx->host_af, sx->interface,
1620 sx->ob->connect_timeout, sx->tblock);
1621
1622 if (sx->inblock.sock < 0)
1623 {
1624 uschar * msg = NULL;
1625 if (sx->verify)
1626 {
1627 msg = US strerror(errno);
1628 HDEBUG(D_verify) debug_printf("connect: %s\n", msg);
1629 }
1630 set_errno_nohost(sx->addrlist,
1631 errno == ETIMEDOUT ? ERRNO_CONNECTTIMEOUT : errno,
1632 sx->verify ? string_sprintf("could not connect: %s", msg)
1633 : NULL,
1634 DEFER, FALSE);
1635 sx->send_quit = FALSE;
1636 return DEFER;
1637 }
1638
1639 /* Expand the greeting message while waiting for the initial response. (Makes
1640 sense if helo_data contains ${lookup dnsdb ...} stuff). The expansion is
1641 delayed till here so that $sending_interface and $sending_port are set. */
1642
1643 if (sx->helo_data)
1644 if (!(sx->helo_data = expand_string(sx->helo_data)))
1645 if (sx->verify)
1646 log_write(0, LOG_MAIN|LOG_PANIC,
1647 "<%s>: failed to expand transport's helo_data value for callout: %s",
1648 sx->addrlist->address, expand_string_message);
1649
1650 #ifdef SUPPORT_I18N
1651 if (sx->helo_data)
1652 {
1653 expand_string_message = NULL;
1654 if ((sx->helo_data = string_domain_utf8_to_alabel(sx->helo_data,
1655 &expand_string_message)),
1656 expand_string_message)
1657 if (sx->verify)
1658 log_write(0, LOG_MAIN|LOG_PANIC,
1659 "<%s>: failed to expand transport's helo_data value for callout: %s",
1660 sx->addrlist->address, expand_string_message);
1661 else
1662 sx->helo_data = NULL;
1663 }
1664 #endif
1665
1666 /* The first thing is to wait for an initial OK response. The dreaded "goto"
1667 is nevertheless a reasonably clean way of programming this kind of logic,
1668 where you want to escape on any error. */
1669
1670 if (!sx->smtps)
1671 {
1672 BOOL good_response;
1673
1674 #ifdef TCP_QUICKACK
1675 (void) setsockopt(sx->inblock.sock, IPPROTO_TCP, TCP_QUICKACK, US &off, sizeof(off));
1676 #endif
1677 good_response = smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
1678 '2', sx->ob->command_timeout);
1679 #ifdef EXPERIMENTAL_DSN_INFO
1680 sx->smtp_greeting = string_copy(sx->buffer);
1681 #endif
1682 if (!good_response) goto RESPONSE_FAILED;
1683
1684 #ifndef DISABLE_EVENT
1685 {
1686 uschar * s;
1687 lookup_dnssec_authenticated = sx->host->dnssec==DS_YES ? US"yes"
1688 : sx->host->dnssec==DS_NO ? US"no" : NULL;
1689 s = event_raise(sx->tblock->event_action, US"smtp:connect", sx->buffer);
1690 if (s)
1691 {
1692 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL,
1693 string_sprintf("deferred by smtp:connect event expansion: %s", s),
1694 DEFER, FALSE);
1695 yield = DEFER;
1696 goto SEND_QUIT;
1697 }
1698 }
1699 #endif
1700
1701 /* Now check if the helo_data expansion went well, and sign off cleanly if
1702 it didn't. */
1703
1704 if (!sx->helo_data)
1705 {
1706 message = string_sprintf("failed to expand helo_data: %s",
1707 expand_string_message);
1708 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1709 yield = DEFER;
1710 goto SEND_QUIT;
1711 }
1712 }
1713
1714 /** Debugging without sending a message
1715 sx->addrlist->transport_return = DEFER;
1716 goto SEND_QUIT;
1717 **/
1718
1719 /* Errors that occur after this point follow an SMTP command, which is
1720 left in big_buffer by smtp_write_command() for use in error messages. */
1721
1722 smtp_command = big_buffer;
1723
1724 /* Tell the remote who we are...
1725
1726 February 1998: A convention has evolved that ESMTP-speaking MTAs include the
1727 string "ESMTP" in their greeting lines, so make Exim send EHLO if the
1728 greeting is of this form. The assumption was that the far end supports it
1729 properly... but experience shows that there are some that give 5xx responses,
1730 even though the banner includes "ESMTP" (there's a bloody-minded one that
1731 says "ESMTP not spoken here"). Cope with that case.
1732
1733 September 2000: Time has passed, and it seems reasonable now to always send
1734 EHLO at the start. It is also convenient to make the change while installing
1735 the TLS stuff.
1736
1737 July 2003: Joachim Wieland met a broken server that advertises "PIPELINING"
1738 but times out after sending MAIL FROM, RCPT TO and DATA all together. There
1739 would be no way to send out the mails, so there is now a host list
1740 "hosts_avoid_esmtp" that disables ESMTP for special hosts and solves the
1741 PIPELINING problem as well. Maybe it can also be useful to cure other
1742 problems with broken servers.
1743
1744 Exim originally sent "Helo" at this point and ran for nearly a year that way.
1745 Then somebody tried it with a Microsoft mailer... It seems that all other
1746 mailers use upper case for some reason (the RFC is quite clear about case
1747 independence) so, for peace of mind, I gave in. */
1748
1749 sx->esmtp = verify_check_given_host(&sx->ob->hosts_avoid_esmtp, sx->host) != OK;
1750
1751 /* Alas; be careful, since this goto is not an error-out, so conceivably
1752 we might set data between here and the target which we assume to exist
1753 and be usable. I can see this coming back to bite us. */
1754 #ifdef SUPPORT_TLS
1755 if (sx->smtps)
1756 {
1757 smtp_peer_options |= OPTION_TLS;
1758 suppress_tls = FALSE;
1759 sx->ob->tls_tempfail_tryclear = FALSE;
1760 smtp_command = US"SSL-on-connect";
1761 goto TLS_NEGOTIATE;
1762 }
1763 #endif
1764
1765 if (sx->esmtp)
1766 {
1767 if (smtp_write_command(&sx->outblock, SCMD_FLUSH, "%s %s\r\n",
1768 sx->lmtp ? "LHLO" : "EHLO", sx->helo_data) < 0)
1769 goto SEND_FAILED;
1770 sx->esmtp_sent = TRUE;
1771 if (!smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer), '2',
1772 sx->ob->command_timeout))
1773 {
1774 if (errno != 0 || sx->buffer[0] == 0 || sx->lmtp)
1775 {
1776 #ifdef EXPERIMENTAL_DSN_INFO
1777 sx->helo_response = string_copy(sx->buffer);
1778 #endif
1779 goto RESPONSE_FAILED;
1780 }
1781 sx->esmtp = FALSE;
1782 }
1783 #ifdef EXPERIMENTAL_DSN_INFO
1784 sx->helo_response = string_copy(sx->buffer);
1785 #endif
1786 }
1787 else
1788 DEBUG(D_transport)
1789 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
1790
1791 if (!sx->esmtp)
1792 {
1793 BOOL good_response;
1794 int n = sizeof(sx->buffer);
1795 uschar * rsp = sx->buffer;
1796
1797 if (sx->esmtp_sent && (n = Ustrlen(sx->buffer)) < sizeof(sx->buffer)/2)
1798 { rsp = sx->buffer + n + 1; n = sizeof(sx->buffer) - n; }
1799
1800 if (smtp_write_command(&sx->outblock, SCMD_FLUSH, "HELO %s\r\n", sx->helo_data) < 0)
1801 goto SEND_FAILED;
1802 good_response = smtp_read_response(&sx->inblock, rsp, n,
1803 '2', sx->ob->command_timeout);
1804 #ifdef EXPERIMENTAL_DSN_INFO
1805 sx->helo_response = string_copy(rsp);
1806 #endif
1807 if (!good_response)
1808 {
1809 /* Handle special logging for a closed connection after HELO
1810 when had previously sent EHLO */
1811
1812 if (rsp != sx->buffer && rsp[0] == 0 && (errno == 0 || errno == ECONNRESET))
1813 {
1814 errno = ERRNO_SMTPCLOSED;
1815 goto EHLOHELO_FAILED;
1816 }
1817 Ustrncpy(sx->buffer, rsp, sizeof(sx->buffer)/2);
1818 goto RESPONSE_FAILED;
1819 }
1820 }
1821
1822 sx->avoid_option = sx->peer_offered = smtp_peer_options = 0;
1823
1824 if (sx->esmtp || sx->lmtp)
1825 {
1826 sx->peer_offered = ehlo_response(sx->buffer,
1827 OPTION_TLS /* others checked later */
1828 );
1829
1830 /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
1831
1832 #ifdef SUPPORT_TLS
1833 smtp_peer_options |= sx->peer_offered & OPTION_TLS;
1834 #endif
1835 }
1836 }
1837
1838 /* For continuing deliveries down the same channel, having re-exec'd the socket
1839 is the standard input; for a socket held open from verify it is recorded
1840 in the cutthrough context block. Either way we don't need to redo EHLO here
1841 (but may need to do so for TLS - see below).
1842 Set up the pointer to where subsequent commands will be left, for
1843 error messages. Note that smtp_peer_options will have been
1844 set from the command line if they were set in the process that passed the
1845 connection on. */
1846
1847 /*XXX continue case needs to propagate DSN_INFO, prob. in deliver.c
1848 as the continue goes via transport_pass_socket() and doublefork and exec.
1849 It does not wait. Unclear how we keep separate host's responses
1850 separate - we could match up by host ip+port as a bodge. */
1851
1852 else
1853 {
1854 if (cutthrough.fd >= 0 && cutthrough.callout_hold_only)
1855 {
1856 sx->inblock.sock = sx->outblock.sock = cutthrough.fd;
1857 sx->host->port = sx->port = cutthrough.host.port;
1858 }
1859 else
1860 {
1861 sx->inblock.sock = sx->outblock.sock = 0; /* stdin */
1862 smtp_port_for_connect(sx->host, sx->port); /* Record the port that was used */
1863 }
1864 smtp_command = big_buffer;
1865 sx->helo_data = NULL; /* ensure we re-expand ob->helo_data */
1866
1867 /* For a continued connection with TLS being proxied for us, or a
1868 held-open verify connection with TLS, nothing more to do. */
1869
1870 if ( continue_proxy_cipher
1871 || (cutthrough.fd >= 0 && cutthrough.callout_hold_only && cutthrough.is_tls)
1872 )
1873 {
1874 sx->peer_offered = smtp_peer_options;
1875 pipelining_active = !!(smtp_peer_options & OPTION_PIPE);
1876 HDEBUG(D_transport) debug_printf("continued connection, %s TLS\n",
1877 continue_proxy_cipher ? "proxied" : "verify conn with");
1878 return OK;
1879 }
1880 HDEBUG(D_transport) debug_printf("continued connection, no TLS\n");
1881 }
1882
1883 /* If TLS is available on this connection, whether continued or not, attempt to
1884 start up a TLS session, unless the host is in hosts_avoid_tls. If successful,
1885 send another EHLO - the server may give a different answer in secure mode. We
1886 use a separate buffer for reading the response to STARTTLS so that if it is
1887 negative, the original EHLO data is available for subsequent analysis, should
1888 the client not be required to use TLS. If the response is bad, copy the buffer
1889 for error analysis. */
1890
1891 #ifdef SUPPORT_TLS
1892 if ( smtp_peer_options & OPTION_TLS
1893 && !suppress_tls
1894 && verify_check_given_host(&sx->ob->hosts_avoid_tls, sx->host) != OK
1895 && ( !sx->verify
1896 || verify_check_given_host(&sx->ob->hosts_verify_avoid_tls, sx->host) != OK
1897 ) )
1898 {
1899 uschar buffer2[4096];
1900 if (smtp_write_command(&sx->outblock, SCMD_FLUSH, "STARTTLS\r\n") < 0)
1901 goto SEND_FAILED;
1902
1903 /* If there is an I/O error, transmission of this message is deferred. If
1904 there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is
1905 false, we also defer. However, if there is a temporary rejection of STARTTLS
1906 and tls_tempfail_tryclear is true, or if there is an outright rejection of
1907 STARTTLS, we carry on. This means we will try to send the message in clear,
1908 unless the host is in hosts_require_tls (tested below). */
1909
1910 if (!smtp_read_response(&sx->inblock, buffer2, sizeof(buffer2), '2',
1911 sx->ob->command_timeout))
1912 {
1913 if ( errno != 0
1914 || buffer2[0] == 0
1915 || (buffer2[0] == '4' && !sx->ob->tls_tempfail_tryclear)
1916 )
1917 {
1918 Ustrncpy(sx->buffer, buffer2, sizeof(sx->buffer));
1919 sx->buffer[sizeof(sx->buffer)-1] = '\0';
1920 goto RESPONSE_FAILED;
1921 }
1922 }
1923
1924 /* STARTTLS accepted: try to negotiate a TLS session. */
1925
1926 else
1927 TLS_NEGOTIATE:
1928 {
1929 address_item * addr;
1930 uschar * errstr;
1931 int rc = tls_client_start(sx->inblock.sock, sx->host, sx->addrlist, sx->tblock,
1932 # ifdef EXPERIMENTAL_DANE
1933 sx->dane ? &tlsa_dnsa : NULL,
1934 # endif
1935 &errstr);
1936
1937 /* TLS negotiation failed; give an error. From outside, this function may
1938 be called again to try in clear on a new connection, if the options permit
1939 it for this host. */
1940
1941 if (rc != OK)
1942 {
1943 # ifdef EXPERIMENTAL_DANE
1944 if (sx->dane) log_write(0, LOG_MAIN,
1945 "DANE attempt failed; TLS connection to %s [%s]: %s",
1946 sx->host->name, sx->host->address, errstr);
1947 # endif
1948
1949 errno = ERRNO_TLSFAILURE;
1950 message = string_sprintf("TLS session: %s", errstr);
1951 sx->send_quit = FALSE;
1952 goto TLS_FAILED;
1953 }
1954
1955 /* TLS session is set up */
1956
1957 smtp_peer_options_wrap = smtp_peer_options;
1958 for (addr = sx->addrlist; addr; addr = addr->next)
1959 if (addr->transport_return == PENDING_DEFER)
1960 {
1961 addr->cipher = tls_out.cipher;
1962 addr->ourcert = tls_out.ourcert;
1963 addr->peercert = tls_out.peercert;
1964 addr->peerdn = tls_out.peerdn;
1965 addr->ocsp = tls_out.ocsp;
1966 }
1967 }
1968 }
1969
1970 /* if smtps, we'll have smtp_command set to something else; always safe to
1971 reset it here. */
1972 smtp_command = big_buffer;
1973
1974 /* If we started TLS, redo the EHLO/LHLO exchange over the secure channel. If
1975 helo_data is null, we are dealing with a connection that was passed from
1976 another process, and so we won't have expanded helo_data above. We have to
1977 expand it here. $sending_ip_address and $sending_port are set up right at the
1978 start of the Exim process (in exim.c). */
1979
1980 if (tls_out.active >= 0)
1981 {
1982 char *greeting_cmd;
1983 BOOL good_response;
1984
1985 if (!sx->helo_data && !(sx->helo_data = expand_string(sx->ob->helo_data)))
1986 {
1987 uschar *message = string_sprintf("failed to expand helo_data: %s",
1988 expand_string_message);
1989 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, message, DEFER, FALSE);
1990 yield = DEFER;
1991 goto SEND_QUIT;
1992 }
1993
1994 /* For SMTPS we need to wait for the initial OK response. */
1995 if (sx->smtps)
1996 {
1997 good_response = smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
1998 '2', sx->ob->command_timeout);
1999 #ifdef EXPERIMENTAL_DSN_INFO
2000 sx->smtp_greeting = string_copy(sx->buffer);
2001 #endif
2002 if (!good_response) goto RESPONSE_FAILED;
2003 }
2004
2005 if (sx->esmtp)
2006 greeting_cmd = "EHLO";
2007 else
2008 {
2009 greeting_cmd = "HELO";
2010 DEBUG(D_transport)
2011 debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
2012 }
2013
2014 if (smtp_write_command(&sx->outblock, SCMD_FLUSH, "%s %s\r\n",
2015 sx->lmtp ? "LHLO" : greeting_cmd, sx->helo_data) < 0)
2016 goto SEND_FAILED;
2017 good_response = smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer),
2018 '2', sx->ob->command_timeout);
2019 #ifdef EXPERIMENTAL_DSN_INFO
2020 sx->helo_response = string_copy(sx->buffer);
2021 #endif
2022 if (!good_response) goto RESPONSE_FAILED;
2023 smtp_peer_options = 0;
2024 }
2025
2026 /* If the host is required to use a secure channel, ensure that we
2027 have one. */
2028
2029 else if ( sx->smtps
2030 # ifdef EXPERIMENTAL_DANE
2031 || sx->dane
2032 # endif
2033 || verify_check_given_host(&sx->ob->hosts_require_tls, sx->host) == OK
2034 )
2035 {
2036 errno = ERRNO_TLSREQUIRED;
2037 message = string_sprintf("a TLS session is required, but %s",
2038 smtp_peer_options & OPTION_TLS
2039 ? "an attempt to start TLS failed" : "the server did not offer TLS support");
2040 goto TLS_FAILED;
2041 }
2042 #endif /*SUPPORT_TLS*/
2043
2044 /* If TLS is active, we have just started it up and re-done the EHLO command,
2045 so its response needs to be analyzed. If TLS is not active and this is a
2046 continued session down a previously-used socket, we haven't just done EHLO, so
2047 we skip this. */
2048
2049 if (continue_hostname == NULL
2050 #ifdef SUPPORT_TLS
2051 || tls_out.active >= 0
2052 #endif
2053 )
2054 {
2055 if (sx->esmtp || sx->lmtp)
2056 {
2057 sx->peer_offered = ehlo_response(sx->buffer,
2058 0 /* no TLS */
2059 | (sx->lmtp && sx->ob->lmtp_ignore_quota ? OPTION_IGNQ : 0)
2060 | OPTION_CHUNKING
2061 | OPTION_PRDR
2062 #ifdef SUPPORT_I18N
2063 | (sx->addrlist->prop.utf8_msg ? OPTION_UTF8 : 0)
2064 /*XXX if we hand peercaps on to continued-conn processes,
2065 must not depend on this addr */
2066 #endif
2067 | OPTION_DSN
2068 | OPTION_PIPE
2069 | (sx->ob->size_addition >= 0 ? OPTION_SIZE : 0)
2070 );
2071
2072 /* Set for IGNOREQUOTA if the response to LHLO specifies support and the
2073 lmtp_ignore_quota option was set. */
2074
2075 sx->igquotstr = sx->peer_offered & OPTION_IGNQ ? US" IGNOREQUOTA" : US"";
2076
2077 /* If the response to EHLO specified support for the SIZE parameter, note
2078 this, provided size_addition is non-negative. */
2079
2080 smtp_peer_options |= sx->peer_offered & OPTION_SIZE;
2081
2082 /* Note whether the server supports PIPELINING. If hosts_avoid_esmtp matched
2083 the current host, esmtp will be false, so PIPELINING can never be used. If
2084 the current host matches hosts_avoid_pipelining, don't do it. */
2085
2086 if ( sx->peer_offered & OPTION_PIPE
2087 && verify_check_given_host(&sx->ob->hosts_avoid_pipelining, sx->host) != OK)
2088 smtp_peer_options |= OPTION_PIPE;
2089
2090 DEBUG(D_transport) debug_printf("%susing PIPELINING\n",
2091 smtp_peer_options & OPTION_PIPE ? "" : "not ");
2092
2093 if ( sx->peer_offered & OPTION_CHUNKING
2094 && verify_check_given_host(&sx->ob->hosts_try_chunking, sx->host) != OK)
2095 sx->peer_offered &= ~OPTION_CHUNKING;
2096
2097 if (sx->peer_offered & OPTION_CHUNKING)
2098 {DEBUG(D_transport) debug_printf("CHUNKING usable\n");}
2099
2100 #ifndef DISABLE_PRDR
2101 if ( sx->peer_offered & OPTION_PRDR
2102 && verify_check_given_host(&sx->ob->hosts_try_prdr, sx->host) != OK)
2103 sx->peer_offered &= ~OPTION_PRDR;
2104
2105 if (sx->peer_offered & OPTION_PRDR)
2106 {DEBUG(D_transport) debug_printf("PRDR usable\n");}
2107 #endif
2108
2109 /* Note if the server supports DSN */
2110 smtp_peer_options |= sx->peer_offered & OPTION_DSN;
2111 DEBUG(D_transport) debug_printf("%susing DSN\n",
2112 sx->peer_offered & OPTION_DSN ? "" : "not ");
2113
2114 /* Note if the response to EHLO specifies support for the AUTH extension.
2115 If it has, check that this host is one we want to authenticate to, and do
2116 the business. The host name and address must be available when the
2117 authenticator's client driver is running. */
2118
2119 switch (yield = smtp_auth(sx->buffer, sizeof(sx->buffer), sx->addrlist, sx->host,
2120 sx->ob, sx->esmtp, &sx->inblock, &sx->outblock))
2121 {
2122 default: goto SEND_QUIT;
2123 case OK: break;
2124 case FAIL_SEND: goto SEND_FAILED;
2125 case FAIL: goto RESPONSE_FAILED;
2126 }
2127 }
2128 }
2129 pipelining_active = !!(smtp_peer_options & OPTION_PIPE);
2130
2131 /* The setting up of the SMTP call is now complete. Any subsequent errors are
2132 message-specific. */
2133
2134 sx->setting_up = FALSE;
2135
2136 #ifdef SUPPORT_I18N
2137 if (sx->addrlist->prop.utf8_msg)
2138 {
2139 sx->utf8_needed = !sx->addrlist->prop.utf8_downcvt
2140 && !sx->addrlist->prop.utf8_downcvt_maybe;
2141 DEBUG(D_transport) if (!sx->utf8_needed)
2142 debug_printf("utf8: %s downconvert\n",
2143 sx->addrlist->prop.utf8_downcvt ? "mandatory" : "optional");
2144 }
2145
2146 /* If this is an international message we need the host to speak SMTPUTF8 */
2147 if (sx->utf8_needed && !(sx->peer_offered & OPTION_UTF8))
2148 {
2149 errno = ERRNO_UTF8_FWD;
2150 goto RESPONSE_FAILED;
2151 }
2152 #endif
2153
2154 return OK;
2155
2156
2157 {
2158 int code;
2159
2160 RESPONSE_FAILED:
2161 message = NULL;
2162 sx->send_quit = check_response(sx->host, &errno, sx->addrlist->more_errno,
2163 sx->buffer, &code, &message, &pass_message);
2164 goto FAILED;
2165
2166 SEND_FAILED:
2167 code = '4';
2168 message = US string_sprintf("send() to %s [%s] failed: %s",
2169 sx->host->name, sx->host->address, strerror(errno));
2170 sx->send_quit = FALSE;
2171 goto FAILED;
2172
2173 /* This label is jumped to directly when a TLS negotiation has failed,
2174 or was not done for a host for which it is required. Values will be set
2175 in message and errno, and setting_up will always be true. Treat as
2176 a temporary error. */
2177
2178 EHLOHELO_FAILED:
2179 code = '4';
2180 message = string_sprintf("Remote host closed connection in response to %s"
2181 " (EHLO response was: %s)", smtp_command, sx->buffer);
2182 sx->send_quit = FALSE;
2183 goto FAILED;
2184
2185 #ifdef SUPPORT_TLS
2186 TLS_FAILED:
2187 code = '4';
2188 goto FAILED;
2189 #endif
2190
2191 /* The failure happened while setting up the call; see if the failure was
2192 a 5xx response (this will either be on connection, or following HELO - a 5xx
2193 after EHLO causes it to try HELO). If so, and there are no more hosts to try,
2194 fail all addresses, as this host is never going to accept them. For other
2195 errors during setting up (timeouts or whatever), defer all addresses, and
2196 yield DEFER, so that the host is not tried again for a while.
2197
2198 XXX This peeking for another host feels like a layering violation. We want
2199 to note the host as unusable, but down here we shouldn't know if this was
2200 the last host to try for the addr(list). Perhaps the upper layer should be
2201 the one to do set_errno() ? The problem is that currently the addr is where
2202 errno etc. are stashed, but until we run out of hosts to try the errors are
2203 host-specific. Maybe we should enhance the host_item definition? */
2204
2205 FAILED:
2206 sx->ok = FALSE; /* For when reached by GOTO */
2207 set_errno(sx->addrlist, errno, message,
2208 sx->host->next
2209 ? DEFER
2210 : code == '5'
2211 #ifdef SUPPORT_I18N
2212 || errno == ERRNO_UTF8_FWD
2213 #endif
2214 ? FAIL : DEFER,
2215 pass_message, sx->host
2216 #ifdef EXPERIMENTAL_DSN_INFO
2217 , sx->smtp_greeting, sx->helo_response
2218 #endif
2219 );
2220 yield = DEFER;
2221 }
2222
2223
2224 SEND_QUIT:
2225
2226 if (sx->send_quit)
2227 (void)smtp_write_command(&sx->outblock, SCMD_FLUSH, "QUIT\r\n");
2228
2229 #ifdef SUPPORT_TLS
2230 tls_close(FALSE, TRUE);
2231 #endif
2232
2233 /* Close the socket, and return the appropriate value, first setting
2234 works because the NULL setting is passed back to the calling process, and
2235 remote_max_parallel is forced to 1 when delivering over an existing connection,
2236 */
2237
2238 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
2239 if (sx->send_quit)
2240 {
2241 shutdown(sx->outblock.sock, SHUT_WR);
2242 if (fcntl(sx->inblock.sock, F_SETFL, O_NONBLOCK) == 0)
2243 for (rc = 16; read(sx->inblock.sock, sx->inbuffer, sizeof(sx->inbuffer)) > 0 && rc > 0;)
2244 rc--; /* drain socket */
2245 sx->send_quit = FALSE;
2246 }
2247 (void)close(sx->inblock.sock);
2248 sx->inblock.sock = sx->outblock.sock = -1;
2249
2250 #ifndef DISABLE_EVENT
2251 (void) event_raise(sx->tblock->event_action, US"tcp:close", NULL);
2252 #endif
2253
2254 continue_transport = NULL;
2255 continue_hostname = NULL;
2256 return yield;
2257 }
2258
2259
2260
2261
2262 /* Create the string of options that will be appended to the MAIL FROM:
2263 in the connection context buffer */
2264
2265 static int
2266 build_mailcmd_options(smtp_context * sx, address_item * addrlist)
2267 {
2268 uschar * p = sx->buffer;
2269 address_item * addr;
2270 int address_count;
2271
2272 *p = 0;
2273
2274 /* If we know the receiving MTA supports the SIZE qualification, and we know it,
2275 send it, adding something to the message size to allow for imprecision
2276 and things that get added en route. Exim keeps the number of lines
2277 in a message, so we can give an accurate value for the original message, but we
2278 need some additional to handle added headers. (Double "." characters don't get
2279 included in the count.) */
2280
2281 if ( message_size > 0
2282 && sx->peer_offered & OPTION_SIZE && !(sx->avoid_option & OPTION_SIZE))
2283 {
2284 /*XXX problem here under spool_files_wireformat?
2285 Or just forget about lines? Or inflate by a fixed proportion? */
2286
2287 sprintf(CS p, " SIZE=%d", message_size+message_linecount+sx->ob->size_addition);
2288 while (*p) p++;
2289 }
2290
2291 #ifndef DISABLE_PRDR
2292 /* If it supports Per-Recipient Data Reponses, and we have omre than one recipient,
2293 request that */
2294
2295 sx->prdr_active = FALSE;
2296 if (sx->peer_offered & OPTION_PRDR)
2297 for (addr = addrlist; addr; addr = addr->next)
2298 if (addr->transport_return == PENDING_DEFER)
2299 {
2300 for (addr = addr->next; addr; addr = addr->next)
2301 if (addr->transport_return == PENDING_DEFER)
2302 { /* at least two recipients to send */
2303 sx->prdr_active = TRUE;
2304 sprintf(CS p, " PRDR"); p += 5;
2305 break;
2306 }
2307 break;
2308 }
2309 #endif
2310
2311 #ifdef SUPPORT_I18N
2312 /* If it supports internationalised messages, and this meesage need that,
2313 request it */
2314
2315 if ( sx->peer_offered & OPTION_UTF8
2316 && addrlist->prop.utf8_msg
2317 && !addrlist->prop.utf8_downcvt
2318 )
2319 Ustrcpy(p, " SMTPUTF8"), p += 9;
2320 #endif
2321
2322 /* check if all addresses have DSN-lasthop flag; do not send RET and ENVID if so */
2323 for (sx->dsn_all_lasthop = TRUE, addr = addrlist, address_count = 0;
2324 addr && address_count < sx->max_rcpt;
2325 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
2326 {
2327 address_count++;
2328 if (!(addr->dsn_flags & rf_dsnlasthop))
2329 {
2330 sx->dsn_all_lasthop = FALSE;
2331 break;
2332 }
2333 }
2334
2335 /* Add any DSN flags to the mail command */
2336
2337 if (sx->peer_offered & OPTION_DSN && !sx->dsn_all_lasthop)
2338 {
2339 if (dsn_ret == dsn_ret_hdrs)
2340 { Ustrcpy(p, " RET=HDRS"); p += 9; }
2341 else if (dsn_ret == dsn_ret_full)
2342 { Ustrcpy(p, " RET=FULL"); p += 9; }
2343
2344 if (dsn_envid)
2345 {
2346 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ENVID=%s", dsn_envid);
2347 while (*p) p++;
2348 }
2349 }
2350
2351 /* If an authenticated_sender override has been specified for this transport
2352 instance, expand it. If the expansion is forced to fail, and there was already
2353 an authenticated_sender for this message, the original value will be used.
2354 Other expansion failures are serious. An empty result is ignored, but there is
2355 otherwise no check - this feature is expected to be used with LMTP and other
2356 cases where non-standard addresses (e.g. without domains) might be required. */
2357
2358 if (smtp_mail_auth_str(p, sizeof(sx->buffer) - (p-sx->buffer), addrlist, sx->ob))
2359 return ERROR;
2360
2361 return OK;
2362 }
2363
2364
2365 static void
2366 build_rcptcmd_options(smtp_context * sx, const address_item * addr)
2367 {
2368 uschar * p = sx->buffer;
2369 *p = 0;
2370
2371 /* Add any DSN flags to the rcpt command */
2372
2373 if (sx->peer_offered & OPTION_DSN && !(addr->dsn_flags & rf_dsnlasthop))
2374 {
2375 if (addr->dsn_flags & rf_dsnflags)
2376 {
2377 int i;
2378 BOOL first = TRUE;
2379
2380 Ustrcpy(p, " NOTIFY=");
2381 while (*p) p++;
2382 for (i = 0; i < nelem(rf_list); i++) if (addr->dsn_flags & rf_list[i])
2383 {
2384 if (!first) *p++ = ',';
2385 first = FALSE;
2386 Ustrcpy(p, rf_names[i]);
2387 while (*p) p++;
2388 }
2389 }
2390
2391 if (addr->dsn_orcpt)
2392 {
2393 string_format(p, sizeof(sx->buffer) - (p-sx->buffer), " ORCPT=%s",
2394 addr->dsn_orcpt);
2395 while (*p) p++;
2396 }
2397 }
2398 }
2399
2400
2401
2402 /*
2403 Return:
2404 0 good, rcpt results in addr->transport_return (PENDING_OK, DEFER, FAIL)
2405 -1 MAIL response error
2406 -2 any non-MAIL read i/o error
2407 -3 non-MAIL response timeout
2408 -4 internal error; channel still usable
2409 -5 transmit failed
2410 */
2411
2412 int
2413 smtp_write_mail_and_rcpt_cmds(smtp_context * sx, int * yield)
2414 {
2415 address_item * addr;
2416 int address_count;
2417 int rc;
2418
2419 if (build_mailcmd_options(sx, sx->first_addr) != OK)
2420 {
2421 *yield = ERROR;
2422 return -4;
2423 }
2424
2425 /* From here until we send the DATA command, we can make use of PIPELINING
2426 if the server host supports it. The code has to be able to check the responses
2427 at any point, for when the buffer fills up, so we write it totally generally.
2428 When PIPELINING is off, each command written reports that it has flushed the
2429 buffer. */
2430
2431 sx->pending_MAIL = TRUE; /* The block starts with MAIL */
2432
2433 {
2434 uschar * s = sx->from_addr;
2435 #ifdef SUPPORT_I18N
2436 uschar * errstr = NULL;
2437
2438 /* If we must downconvert, do the from-address here. Remember we had to
2439 for the to-addresses (done below), and also (ugly) for re-doing when building
2440 the delivery log line. */
2441
2442 if ( sx->addrlist->prop.utf8_msg
2443 && (sx->addrlist->prop.utf8_downcvt || !(sx->peer_offered & OPTION_UTF8))
2444 )
2445 {
2446 if (s = string_address_utf8_to_alabel(s, &errstr), errstr)
2447 {
2448 set_errno_nohost(sx->addrlist, ERRNO_EXPANDFAIL, errstr, DEFER, FALSE);
2449 *yield = ERROR;
2450 return -4;
2451 }
2452 setflag(sx->addrlist, af_utf8_downcvt);
2453 }
2454 #endif
2455
2456 rc = smtp_write_command(&sx->outblock, pipelining_active ? SCMD_BUFFER : SCMD_FLUSH,
2457 "MAIL FROM:<%s>%s\r\n", s, sx->buffer);
2458 }
2459
2460 mail_command = string_copy(big_buffer); /* Save for later error message */
2461
2462 switch(rc)
2463 {
2464 case -1: /* Transmission error */
2465 return -5;
2466
2467 case +1: /* Cmd was sent */
2468 if (!smtp_read_response(&sx->inblock, sx->buffer, sizeof(sx->buffer), '2',
2469 sx->ob->command_timeout))
2470 {
2471 if (errno == 0 && sx->buffer[0] == '4')
2472 {
2473 errno = ERRNO_MAIL4XX;
2474 sx->addrlist->more_errno |= ((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
2475 }
2476 return -1;
2477 }
2478 sx->pending_MAIL = FALSE;
2479 break;
2480
2481 /* otherwise zero: command queued for pipeline */
2482 }
2483
2484 /* Pass over all the relevant recipient addresses for this host, which are the
2485 ones that have status PENDING_DEFER. If we are using PIPELINING, we can send
2486 several before we have to read the responses for those seen so far. This
2487 checking is done by a subroutine because it also needs to be done at the end.
2488 Send only up to max_rcpt addresses at a time, leaving next_addr pointing to
2489 the next one if not all are sent.
2490
2491 In the MUA wrapper situation, we want to flush the PIPELINING buffer for the
2492 last address because we want to abort if any recipients have any kind of
2493 problem, temporary or permanent. We know that all recipient addresses will have
2494 the PENDING_DEFER status, because only one attempt is ever made, and we know
2495 that max_rcpt will be large, so all addresses will be done at once.
2496
2497 For verify we flush the pipeline after any (the only) rcpt address. */
2498
2499 for (addr = sx->first_addr, address_count = 0;
2500 addr && address_count < sx->max_rcpt;
2501 addr = addr->next) if (addr->transport_return == PENDING_DEFER)
2502 {
2503 int count;
2504 BOOL no_flush;
2505 uschar * rcpt_addr;
2506
2507 addr->dsn_aware = sx->peer_offered & OPTION_DSN
2508 ? dsn_support_yes : dsn_support_no;
2509
2510 address_count++;
2511 no_flush = pipelining_active && !sx->verify
2512 && (!mua_wrapper || addr->next && address_count < sx->max_rcpt);
2513
2514 build_rcptcmd_options(sx, addr);
2515
2516 /* Now send the RCPT command, and process outstanding responses when
2517 necessary. After a timeout on RCPT, we just end the function, leaving the
2518 yield as OK, because this error can often mean that there is a problem with
2519 just one address, so we don't want to delay the host. */
2520
2521 rcpt_addr = transport_rcpt_address(addr, sx->tblock->rcpt_include_affixes);
2522
2523 #ifdef SUPPORT_I18N
2524 if ( testflag(sx->addrlist, af_utf8_downcvt)
2525 && !(rcpt_addr = string_address_utf8_to_alabel(rcpt_addr, NULL))
2526 )
2527 {
2528 /*XXX could we use a per-address errstr here? Not fail the whole send? */
2529 errno = ERRNO_EXPANDFAIL;
2530 return -5; /*XXX too harsh? */
2531 }
2532 #endif
2533
2534 count = smtp_write_command(&sx->outblock, no_flush ? SCMD_BUFFER : SCMD_FLUSH,
2535 "RCPT TO:<%s>%s%s\r\n", rcpt_addr, sx->igquotstr, sx->buffer);
2536
2537 if (count < 0) return -5;
2538 if (count > 0)
2539 {
2540 switch(sync_responses(sx, count, 0))
2541 {
2542 case 3: sx->ok = TRUE; /* 2xx & 5xx => OK & progress made */
2543 case 2: sx->completed_addr = TRUE; /* 5xx (only) => progress made */
2544 break;
2545
2546 case 1: sx->ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2547 if (!sx->lmtp) /* can't tell about progress yet */
2548 sx->completed_addr = TRUE;
2549 case 0: /* No 2xx or 5xx, but no probs */
2550 break;
2551
2552 case -1: return -3; /* Timeout on RCPT */
2553 case -2: return -2; /* non-MAIL read i/o error */
2554 default: return -1; /* any MAIL error */
2555 }
2556 sx->pending_MAIL = FALSE; /* Dealt with MAIL */
2557 }
2558 } /* Loop for next address */
2559
2560 sx->next_addr = addr;
2561 return 0;
2562 }
2563
2564
2565 #ifdef SUPPORT_TLS
2566 /*****************************************************
2567 * Proxy TLS connection for another transport process *
2568 ******************************************************/
2569 /*
2570 Use the given buffer as a staging area, and select on both the given fd
2571 and the TLS'd client-fd for data to read (per the coding in ip_recv() and
2572 fd_ready() this is legitimate). Do blocking full-size writes, and reads
2573 under a timeout.
2574
2575 Arguments:
2576 buf space to use for buffering
2577 bufsiz size of buffer
2578 proxy_fd comms to proxied process
2579 timeout per-read timeout, seconds
2580 */
2581
2582 void
2583 smtp_proxy_tls(uschar * buf, size_t bsize, int proxy_fd, int timeout)
2584 {
2585 fd_set rfds, efds;
2586 int max_fd = MAX(proxy_fd, tls_out.active) + 1;
2587 int rc, i, fd_bits, nbytes;
2588
2589 set_process_info("proxying TLS connection for continued transport");
2590 FD_ZERO(&rfds);
2591 FD_SET(tls_out.active, &rfds);
2592 FD_SET(proxy_fd, &rfds);
2593
2594 for (fd_bits = 3; fd_bits; )
2595 {
2596 time_t time_left = timeout;
2597 time_t time_start = time(NULL);
2598
2599 /* wait for data */
2600 efds = rfds;
2601 do
2602 {
2603 struct timeval tv = { time_left, 0 };
2604
2605 rc = select(max_fd,
2606 (SELECT_ARG2_TYPE *)&rfds, NULL, (SELECT_ARG2_TYPE *)&efds, &tv);
2607
2608 if (rc < 0 && errno == EINTR)
2609 if ((time_left -= time(NULL) - time_start) > 0) continue;
2610
2611 if (rc <= 0)
2612 {
2613 DEBUG(D_transport) if (rc == 0) debug_printf("%s: timed out\n", __FUNCTION__);
2614 return;
2615 }
2616
2617 if (FD_ISSET(tls_out.active, &efds) || FD_ISSET(proxy_fd, &efds))
2618 {
2619 DEBUG(D_transport) debug_printf("select: exceptional cond on %s fd\n",
2620 FD_ISSET(proxy_fd, &efds) ? "proxy" : "tls");
2621 return;
2622 }
2623 }
2624 while (rc < 0 || !(FD_ISSET(tls_out.active, &rfds) || FD_ISSET(proxy_fd, &rfds)));
2625
2626 /* handle inbound data */
2627 if (FD_ISSET(tls_out.active, &rfds))
2628 if ((rc = tls_read(FALSE, buf, bsize)) <= 0)
2629 {
2630 fd_bits &= ~1;
2631 FD_CLR(tls_out.active, &rfds);
2632 shutdown(proxy_fd, SHUT_WR);
2633 timeout = 5;
2634 }
2635 else
2636 {
2637 for (nbytes = 0; rc - nbytes > 0; nbytes += i)
2638 if ((i = write(proxy_fd, buf + nbytes, rc - nbytes)) < 0) return;
2639 }
2640 else if (fd_bits & 1)
2641 FD_SET(tls_out.active, &rfds);
2642
2643 /* handle outbound data */
2644 if (FD_ISSET(proxy_fd, &rfds))
2645 if ((rc = read(proxy_fd, buf, bsize)) <= 0)
2646 {
2647 fd_bits = 0;
2648 tls_close(FALSE, TRUE);
2649 }
2650 else
2651 {
2652 for (nbytes = 0; rc - nbytes > 0; nbytes += i)
2653 if ((i = tls_write(FALSE, buf + nbytes, rc - nbytes, FALSE)) < 0)
2654 return;
2655 }
2656 else if (fd_bits & 2)
2657 FD_SET(proxy_fd, &rfds);
2658 }
2659 }
2660 #endif
2661
2662
2663 /*************************************************
2664 * Deliver address list to given host *
2665 *************************************************/
2666
2667 /* If continue_hostname is not null, we get here only when continuing to
2668 deliver down an existing channel. The channel was passed as the standard
2669 input. TLS is never active on a passed channel; the previous process always
2670 closes it down before passing the connection on.
2671
2672 Otherwise, we have to make a connection to the remote host, and do the
2673 initial protocol exchange.
2674
2675 When running as an MUA wrapper, if the sender or any recipient is rejected,
2676 temporarily or permanently, we force failure for all recipients.
2677
2678 Arguments:
2679 addrlist chain of potential addresses to deliver; only those whose
2680 transport_return field is set to PENDING_DEFER are currently
2681 being processed; others should be skipped - they have either
2682 been delivered to an earlier host or IP address, or been
2683 failed by one of them.
2684 host host to deliver to
2685 host_af AF_INET or AF_INET6
2686 defport default TCP/IP port to use if host does not specify, in host
2687 byte order
2688 interface interface to bind to, or NULL
2689 tblock transport instance block
2690 message_defer set TRUE if yield is OK, but all addresses were deferred
2691 because of a non-recipient, non-host failure, that is, a
2692 4xx response to MAIL FROM, DATA, or ".". This is a defer
2693 that is specific to the message.
2694 suppress_tls if TRUE, don't attempt a TLS connection - this is set for
2695 a second attempt after TLS initialization fails
2696
2697 Returns: OK - the connection was made and the delivery attempted;
2698 the result for each address is in its data block.
2699 DEFER - the connection could not be made, or something failed
2700 while setting up the SMTP session, or there was a
2701 non-message-specific error, such as a timeout.
2702 ERROR - a filter command is specified for this transport,
2703 and there was a problem setting it up; OR helo_data
2704 or add_headers or authenticated_sender is specified
2705 for this transport, and the string failed to expand
2706 */
2707
2708 static int
2709 smtp_deliver(address_item *addrlist, host_item *host, int host_af, int defport,
2710 uschar *interface, transport_instance *tblock,
2711 BOOL *message_defer, BOOL suppress_tls)
2712 {
2713 address_item *addr;
2714 int yield = OK;
2715 int save_errno;
2716 int rc;
2717 time_t start_delivery_time = time(NULL);
2718
2719 BOOL pass_message = FALSE;
2720 uschar *message = NULL;
2721 uschar new_message_id[MESSAGE_ID_LENGTH + 1];
2722 uschar *p;
2723
2724 smtp_context sx;
2725
2726 suppress_tls = suppress_tls; /* stop compiler warning when no TLS support */
2727 *message_defer = FALSE;
2728
2729 sx.addrlist = addrlist;
2730 sx.host = host;
2731 sx.host_af = host_af,
2732 sx.port = defport;
2733 sx.interface = interface;
2734 sx.helo_data = NULL;
2735 sx.tblock = tblock;
2736 sx.verify = FALSE;
2737
2738 /* Get the channel set up ready for a message (MAIL FROM being the next
2739 SMTP command to send */
2740
2741 if ((rc = smtp_setup_conn(&sx, suppress_tls)) != OK)
2742 return rc;
2743
2744 /* If there is a filter command specified for this transport, we can now
2745 set it up. This cannot be done until the identify of the host is known. */
2746
2747 if (tblock->filter_command)
2748 {
2749 transport_filter_timeout = tblock->filter_timeout;
2750
2751 /* On failure, copy the error to all addresses, abandon the SMTP call, and
2752 yield ERROR. */
2753
2754 if (!transport_set_up_command(&transport_filter_argv,
2755 tblock->filter_command, TRUE, DEFER, addrlist,
2756 string_sprintf("%.50s transport", tblock->name), NULL))
2757 {
2758 set_errno_nohost(addrlist->next, addrlist->basic_errno, addrlist->message, DEFER,
2759 FALSE);
2760 yield = ERROR;
2761 goto SEND_QUIT;
2762 }
2763
2764 if ( transport_filter_argv
2765 && *transport_filter_argv
2766 && **transport_filter_argv
2767 && sx.peer_offered & OPTION_CHUNKING
2768 )
2769 {
2770 sx.peer_offered &= ~OPTION_CHUNKING;
2771 DEBUG(D_transport) debug_printf("CHUNKING not usable due to transport filter\n");
2772 }
2773 }
2774
2775 sx.first_addr = addrlist;
2776
2777 /* For messages that have more than the maximum number of envelope recipients,
2778 we want to send several transactions down the same SMTP connection. (See
2779 comments in deliver.c as to how this reconciles, heuristically, with
2780 remote_max_parallel.) This optimization was added to Exim after the following
2781 code was already working. The simplest way to put it in without disturbing the
2782 code was to use a goto to jump back to this point when there is another
2783 transaction to handle. */
2784
2785 SEND_MESSAGE:
2786 sx.from_addr = return_path;
2787 sx.sync_addr = sx.first_addr;
2788 sx.ok = FALSE;
2789 sx.send_rset = TRUE;
2790 sx.completed_addr = FALSE;
2791
2792
2793 /* If we are a continued-connection-after-verify the MAIL and RCPT
2794 commands were already sent; do not re-send but do mark the addrs as
2795 having been accepted up to RCPT stage. A traditional cont-conn
2796 always has a sequence number greater than one. */
2797
2798 if (continue_hostname && continue_sequence == 1)
2799 {
2800 address_item * addr;
2801
2802 sx.peer_offered = smtp_peer_options;
2803 sx.pending_MAIL = FALSE;
2804 sx.ok = TRUE;
2805 sx.next_addr = NULL;
2806
2807 for (addr = addrlist; addr; addr = addr->next)
2808 addr->transport_return = PENDING_OK;
2809 }
2810 else
2811 {
2812 /* Initiate a message transfer. */
2813
2814 switch(smtp_write_mail_and_rcpt_cmds(&sx, &yield))
2815 {
2816 case 0: break;
2817 case -1: case -2: goto RESPONSE_FAILED;
2818 case -3: goto END_OFF;
2819 case -4: goto SEND_QUIT;
2820 default: goto SEND_FAILED;
2821 }
2822
2823 /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
2824 permanently or temporarily. We should have flushed and synced after the last
2825 RCPT. */
2826
2827 if (mua_wrapper)
2828 {
2829 address_item * a;
2830 unsigned cnt;
2831
2832 for (a = sx.first_addr, cnt = 0; a && cnt < sx.max_rcpt; a = a->next, cnt++)
2833 if (a->transport_return != PENDING_OK)
2834 {
2835 /*XXX could we find a better errno than 0 here? */
2836 set_errno_nohost(addrlist, 0, a->message, FAIL,
2837 testflag(a, af_pass_message));
2838 sx.ok = FALSE;
2839 break;
2840 }
2841 }
2842 }
2843
2844 /* If ok is TRUE, we know we have got at least one good recipient, and must now
2845 send DATA, but if it is FALSE (in the normal, non-wrapper case), we may still
2846 have a good recipient buffered up if we are pipelining. We don't want to waste
2847 time sending DATA needlessly, so we only send it if either ok is TRUE or if we
2848 are pipelining. The responses are all handled by sync_responses().
2849 If using CHUNKING, do not send a BDAT until we know how big a chunk we want
2850 to send is. */
2851
2852 if ( !(sx.peer_offered & OPTION_CHUNKING)
2853 && (sx.ok || (pipelining_active && !mua_wrapper)))
2854 {
2855 int count = smtp_write_command(&sx.outblock, SCMD_FLUSH, "DATA\r\n");
2856
2857 if (count < 0) goto SEND_FAILED;
2858 switch(sync_responses(&sx, count, sx.ok ? +1 : -1))
2859 {
2860 case 3: sx.ok = TRUE; /* 2xx & 5xx => OK & progress made */
2861 case 2: sx.completed_addr = TRUE; /* 5xx (only) => progress made */
2862 break;
2863
2864 case 1: sx.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2865 if (!sx.lmtp) sx.completed_addr = TRUE; /* can't tell about progress yet */
2866 case 0: break; /* No 2xx or 5xx, but no probs */
2867
2868 case -1: goto END_OFF; /* Timeout on RCPT */
2869 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2870 }
2871 pipelining_active = FALSE;
2872 data_command = string_copy(big_buffer); /* Save for later error message */
2873 }
2874
2875 /* If there were no good recipients (but otherwise there have been no
2876 problems), just set ok TRUE, since we have handled address-specific errors
2877 already. Otherwise, it's OK to send the message. Use the check/escape mechanism
2878 for handling the SMTP dot-handling protocol, flagging to apply to headers as
2879 well as body. Set the appropriate timeout value to be used for each chunk.
2880 (Haven't been able to make it work using select() for writing yet.) */
2881
2882 if (!(sx.peer_offered & OPTION_CHUNKING) && !sx.ok)
2883 {
2884 /* Save the first address of the next batch. */
2885 sx.first_addr = sx.next_addr;
2886
2887 sx.ok = TRUE;
2888 }
2889 else
2890 {
2891 transport_ctx tctx = {
2892 sx.inblock.sock,
2893 tblock,
2894 addrlist,
2895 US".", US"..", /* Escaping strings */
2896 topt_use_crlf | topt_escape_headers
2897 | (tblock->body_only ? topt_no_headers : 0)
2898 | (tblock->headers_only ? topt_no_body : 0)
2899 | (tblock->return_path_add ? topt_add_return_path : 0)
2900 | (tblock->delivery_date_add ? topt_add_delivery_date : 0)
2901 | (tblock->envelope_to_add ? topt_add_envelope_to : 0)
2902 };
2903
2904 /* If using CHUNKING we need a callback from the generic transport
2905 support to us, for the sending of BDAT smtp commands and the reaping
2906 of responses. The callback needs a whole bunch of state so set up
2907 a transport-context structure to be passed around. */
2908
2909 if (sx.peer_offered & OPTION_CHUNKING)
2910 {
2911 tctx.check_string = tctx.escape_string = NULL;
2912 tctx.options |= topt_use_bdat;
2913 tctx.chunk_cb = smtp_chunk_cmd_callback;
2914 sx.pending_BDAT = FALSE;
2915 sx.good_RCPT = sx.ok;
2916 sx.cmd_count = 0;
2917 tctx.smtp_context = &sx;
2918 }
2919 else
2920 tctx.options |= topt_end_dot;
2921
2922 /* Save the first address of the next batch. */
2923 sx.first_addr = sx.next_addr;
2924
2925 /* Responses from CHUNKING commands go in buffer. Otherwise,
2926 there has not been a response. */
2927
2928 sx.buffer[0] = 0;
2929
2930 sigalrm_seen = FALSE;
2931 transport_write_timeout = sx.ob->data_timeout;
2932 smtp_command = US"sending data block"; /* For error messages */
2933 DEBUG(D_transport|D_v)
2934 if (sx.peer_offered & OPTION_CHUNKING)
2935 debug_printf(" will write message using CHUNKING\n");
2936 else
2937 debug_printf(" SMTP>> writing message and terminating \".\"\n");
2938 transport_count = 0;
2939
2940 #ifndef DISABLE_DKIM
2941 sx.ok = dkim_transport_write_message(&tctx, &sx.ob->dkim, CUSS &message);
2942 #else
2943 sx.ok = transport_write_message(&tctx, 0);
2944 #endif
2945
2946 /* transport_write_message() uses write() because it is called from other
2947 places to write to non-sockets. This means that under some OS (e.g. Solaris)
2948 it can exit with "Broken pipe" as its error. This really means that the
2949 socket got closed at the far end. */
2950
2951 transport_write_timeout = 0; /* for subsequent transports */
2952
2953 /* Failure can either be some kind of I/O disaster (including timeout),
2954 or the failure of a transport filter or the expansion of added headers.
2955 Or, when CHUNKING, it can be a protocol-detected failure. */
2956
2957 if (!sx.ok)
2958 if (message) goto SEND_FAILED;
2959 else goto RESPONSE_FAILED;
2960
2961 /* We used to send the terminating "." explicitly here, but because of
2962 buffering effects at both ends of TCP/IP connections, you don't gain
2963 anything by keeping it separate, so it might as well go in the final
2964 data buffer for efficiency. This is now done by setting the topt_end_dot
2965 flag above. */
2966
2967 smtp_command = US"end of data";
2968
2969 if (sx.peer_offered & OPTION_CHUNKING && sx.cmd_count > 1)
2970 {
2971 /* Reap any outstanding MAIL & RCPT commands, but not a DATA-go-ahead */
2972 switch(sync_responses(&sx, sx.cmd_count-1, 0))
2973 {
2974 case 3: sx.ok = TRUE; /* 2xx & 5xx => OK & progress made */
2975 case 2: sx.completed_addr = TRUE; /* 5xx (only) => progress made */
2976 break;
2977
2978 case 1: sx.ok = TRUE; /* 2xx (only) => OK, but if LMTP, */
2979 if (!sx.lmtp) sx.completed_addr = TRUE; /* can't tell about progress yet */
2980 case 0: break; /* No 2xx or 5xx, but no probs */
2981
2982 case -1: goto END_OFF; /* Timeout on RCPT */
2983 default: goto RESPONSE_FAILED; /* I/O error, or any MAIL/DATA error */
2984 }
2985 }
2986
2987 #ifndef DISABLE_PRDR
2988 /* For PRDR we optionally get a partial-responses warning
2989 * followed by the individual responses, before going on with
2990 * the overall response. If we don't get the warning then deal
2991 * with per non-PRDR. */
2992 if(sx.prdr_active)
2993 {
2994 sx.ok = smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer), '3',
2995 sx.ob->final_timeout);
2996 if (!sx.ok && errno == 0) switch(sx.buffer[0])
2997 {
2998 case '2': sx.prdr_active = FALSE;
2999 sx.ok = TRUE;
3000 break;
3001 case '4': errno = ERRNO_DATA4XX;
3002 addrlist->more_errno |=
3003 ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
3004 break;
3005 }
3006 }
3007 else
3008 #endif
3009
3010 /* For non-PRDR SMTP, we now read a single response that applies to the
3011 whole message. If it is OK, then all the addresses have been delivered. */
3012
3013 if (!sx.lmtp)
3014 {
3015 sx.ok = smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer), '2',
3016 sx.ob->final_timeout);
3017 if (!sx.ok && errno == 0 && sx.buffer[0] == '4')
3018 {
3019 errno = ERRNO_DATA4XX;
3020 addrlist->more_errno |= ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
3021 }
3022 }
3023
3024 /* For LMTP, we get back a response for every RCPT command that we sent;
3025 some may be accepted and some rejected. For those that get a response, their
3026 status is fixed; any that are accepted have been handed over, even if later
3027 responses crash - at least, that's how I read RFC 2033.
3028
3029 If all went well, mark the recipient addresses as completed, record which
3030 host/IPaddress they were delivered to, and cut out RSET when sending another
3031 message down the same channel. Write the completed addresses to the journal
3032 now so that they are recorded in case there is a crash of hardware or
3033 software before the spool gets updated. Also record the final SMTP
3034 confirmation if needed (for SMTP only). */
3035
3036 if (sx.ok)
3037 {
3038 int flag = '=';
3039 int delivery_time = (int)(time(NULL) - start_delivery_time);
3040 int len;
3041 uschar *conf = NULL;
3042
3043 sx.send_rset = FALSE;
3044 pipelining_active = FALSE;
3045
3046 /* Set up confirmation if needed - applies only to SMTP */
3047
3048 if (
3049 #ifdef DISABLE_EVENT
3050 LOGGING(smtp_confirmation) &&
3051 #endif
3052 !sx.lmtp
3053 )
3054 {
3055 const uschar *s = string_printing(sx.buffer);
3056 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
3057 conf = (s == sx.buffer)? (uschar *)string_copy(s) : US s;
3058 }
3059
3060 /* Process all transported addresses - for LMTP or PRDR, read a status for
3061 each one. */
3062
3063 for (addr = addrlist; addr != sx.first_addr; addr = addr->next)
3064 {
3065 if (addr->transport_return != PENDING_OK) continue;
3066
3067 /* LMTP - if the response fails badly (e.g. timeout), use it for all the
3068 remaining addresses. Otherwise, it's a return code for just the one
3069 address. For temporary errors, add a retry item for the address so that
3070 it doesn't get tried again too soon. */
3071
3072 #ifndef DISABLE_PRDR
3073 if (sx.lmtp || sx.prdr_active)
3074 #else
3075 if (sx.lmtp)
3076 #endif
3077 {
3078 if (!smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer), '2',
3079 sx.ob->final_timeout))
3080 {
3081 if (errno != 0 || sx.buffer[0] == 0) goto RESPONSE_FAILED;
3082 addr->message = string_sprintf(
3083 #ifndef DISABLE_PRDR
3084 "%s error after %s: %s", sx.prdr_active ? "PRDR":"LMTP",
3085 #else
3086 "LMTP error after %s: %s",
3087 #endif
3088 data_command, string_printing(sx.buffer));
3089 setflag(addr, af_pass_message); /* Allow message to go to user */
3090 if (sx.buffer[0] == '5')
3091 addr->transport_return = FAIL;
3092 else
3093 {
3094 errno = ERRNO_DATA4XX;
3095 addr->more_errno |= ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
3096 addr->transport_return = DEFER;
3097 #ifndef DISABLE_PRDR
3098 if (!sx.prdr_active)
3099 #endif
3100 retry_add_item(addr, addr->address_retry_key, 0);
3101 }
3102 continue;
3103 }
3104 sx.completed_addr = TRUE; /* NOW we can set this flag */
3105 if (LOGGING(smtp_confirmation))
3106 {
3107 const uschar *s = string_printing(sx.buffer);
3108 /* deconst cast ok here as string_printing was checked to have alloc'n'copied */
3109 conf = (s == sx.buffer) ? US string_copy(s) : US s;
3110 }
3111 }
3112
3113 /* SMTP, or success return from LMTP for this address. Pass back the
3114 actual host that was used. */
3115
3116 addr->transport_return = OK;
3117 addr->more_errno = delivery_time;
3118 addr->host_used = host;
3119 addr->special_action = flag;
3120 addr->message = conf;
3121 #ifndef DISABLE_PRDR
3122 if (sx.prdr_active) addr->flags |= af_prdr_used;
3123 #endif
3124 if (sx.peer_offered & OPTION_CHUNKING) addr->flags |= af_chunking_used;
3125 flag = '-';
3126
3127 #ifndef DISABLE_PRDR
3128 if (!sx.prdr_active)
3129 #endif
3130 {
3131 /* Update the journal. For homonymic addresses, use the base address plus
3132 the transport name. See lots of comments in deliver.c about the reasons
3133 for the complications when homonyms are involved. Just carry on after
3134 write error, as it may prove possible to update the spool file later. */
3135
3136 if (testflag(addr, af_homonym))
3137 sprintf(CS sx.buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
3138 else
3139 sprintf(CS sx.buffer, "%.500s\n", addr->unique);
3140
3141 DEBUG(D_deliver) debug_printf("S:journalling %s\n", sx.buffer);
3142 len = Ustrlen(CS sx.buffer);
3143 if (write(journal_fd, sx.buffer, len) != len)
3144 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
3145 "%s: %s", sx.buffer, strerror(errno));
3146 }
3147 }
3148
3149 #ifndef DISABLE_PRDR
3150 if (sx.prdr_active)
3151 {
3152 /* PRDR - get the final, overall response. For any non-success
3153 upgrade all the address statuses. */
3154 sx.ok = smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer), '2',
3155 sx.ob->final_timeout);
3156 if (!sx.ok)
3157 {
3158 if(errno == 0 && sx.buffer[0] == '4')
3159 {
3160 errno = ERRNO_DATA4XX;
3161 addrlist->more_errno |= ((sx.buffer[1] - '0')*10 + sx.buffer[2] - '0') << 8;
3162 }
3163 for (addr = addrlist; addr != sx.first_addr; addr = addr->next)
3164 if (sx.buffer[0] == '5' || addr->transport_return == OK)
3165 addr->transport_return = PENDING_OK; /* allow set_errno action */
3166 goto RESPONSE_FAILED;
3167 }
3168
3169 /* Update the journal, or setup retry. */
3170 for (addr = addrlist; addr != sx.first_addr; addr = addr->next)
3171 if (addr->transport_return == OK)
3172 {
3173 if (testflag(addr, af_homonym))
3174 sprintf(CS sx.buffer, "%.500s/%s\n", addr->unique + 3, tblock->name);
3175 else
3176 sprintf(CS sx.buffer, "%.500s\n", addr->unique);
3177
3178 DEBUG(D_deliver) debug_printf("journalling(PRDR) %s\n", sx.buffer);
3179 len = Ustrlen(CS sx.buffer);
3180 if (write(journal_fd, sx.buffer, len) != len)
3181 log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
3182 "%s: %s", sx.buffer, strerror(errno));
3183 }
3184 else if (addr->transport_return == DEFER)
3185 retry_add_item(addr, addr->address_retry_key, -2);
3186 }
3187 #endif
3188
3189 /* Ensure the journal file is pushed out to disk. */
3190
3191 if (EXIMfsync(journal_fd) < 0)
3192 log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
3193 strerror(errno));
3194 }
3195 }
3196
3197
3198 /* Handle general (not specific to one address) failures here. The value of ok
3199 is used to skip over this code on the falling through case. A timeout causes a
3200 deferral. Other errors may defer or fail according to the response code, and
3201 may set up a special errno value, e.g. after connection chopped, which is
3202 assumed if errno == 0 and there is no text in the buffer. If control reaches
3203 here during the setting up phase (i.e. before MAIL FROM) then always defer, as
3204 the problem is not related to this specific message. */
3205
3206 if (!sx.ok)
3207 {
3208 int code, set_rc;
3209 uschar * set_message;
3210
3211 RESPONSE_FAILED:
3212 {
3213 save_errno = errno;
3214 message = NULL;
3215 sx.send_quit = check_response(host, &save_errno, addrlist->more_errno,
3216 sx.buffer, &code, &message, &pass_message);
3217 goto FAILED;
3218 }
3219
3220 SEND_FAILED:
3221 {
3222 save_errno = errno;
3223 code = '4';
3224 message = string_sprintf("send() to %s [%s] failed: %s",
3225 host->name, host->address, message ? message : US strerror(save_errno));
3226 sx.send_quit = FALSE;
3227 goto FAILED;
3228 }
3229
3230 FAILED:
3231 {
3232 BOOL message_error;
3233
3234 sx.ok = FALSE; /* For when reached by GOTO */
3235 set_message = message;
3236
3237 /* We want to handle timeouts after MAIL or "." and loss of connection after
3238 "." specially. They can indicate a problem with the sender address or with
3239 the contents of the message rather than a real error on the connection. These
3240 cases are treated in the same way as a 4xx response. This next bit of code
3241 does the classification. */
3242
3243 switch(save_errno)
3244 {
3245 case 0:
3246 case ERRNO_MAIL4XX:
3247 case ERRNO_DATA4XX:
3248 message_error = TRUE;
3249 break;
3250
3251 case ETIMEDOUT:
3252 message_error = Ustrncmp(smtp_command,"MAIL",4) == 0 ||
3253 Ustrncmp(smtp_command,"end ",4) == 0;
3254 break;
3255
3256 case ERRNO_SMTPCLOSED:
3257 message_error = Ustrncmp(smtp_command,"end ",4) == 0;
3258 break;
3259
3260 default:
3261 message_error = FALSE;
3262 break;
3263 }
3264
3265 /* Handle the cases that are treated as message errors. These are:
3266
3267 (a) negative response or timeout after MAIL
3268 (b) negative response after DATA
3269 (c) negative response or timeout or dropped connection after "."
3270 (d) utf8 support required and not offered
3271
3272 It won't be a negative response or timeout after RCPT, as that is dealt
3273 with separately above. The action in all cases is to set an appropriate
3274 error code for all the addresses, but to leave yield set to OK because the
3275 host itself has not failed. Of course, it might in practice have failed
3276 when we've had a timeout, but if so, we'll discover that at the next
3277 delivery attempt. For a temporary error, set the message_defer flag, and
3278 write to the logs for information if this is not the last host. The error
3279 for the last host will be logged as part of the address's log line. */
3280
3281 if (message_error)
3282 {
3283 if (mua_wrapper) code = '5'; /* Force hard failure in wrapper mode */
3284
3285 /* If there's an errno, the message contains just the identity of
3286 the host. */
3287
3288 if (code == '5')
3289 set_rc = FAIL;
3290 else /* Anything other than 5 is treated as temporary */
3291 {
3292 set_rc = DEFER;
3293 if (save_errno > 0)
3294 message = US string_sprintf("%s: %s", message, strerror(save_errno));
3295 if (host->next != NULL) log_write(0, LOG_MAIN, "%s", message);
3296 msglog_line(host, message);
3297 *message_defer = TRUE;
3298 }
3299 }
3300
3301 /* Otherwise, we have an I/O error or a timeout other than after MAIL or
3302 ".", or some other transportation error. We defer all addresses and yield
3303 DEFER, except for the case of failed add_headers expansion, or a transport
3304 filter failure, when the yield should be ERROR, to stop it trying other
3305 hosts. */
3306
3307 else
3308 {
3309 set_rc = DEFER;
3310 yield = (save_errno == ERRNO_CHHEADER_FAIL ||
3311 save_errno == ERRNO_FILTER_FAIL)? ERROR : DEFER;
3312 }
3313 }
3314
3315 set_errno(addrlist, save_errno, set_message, set_rc, pass_message, host
3316 #ifdef EXPERIMENTAL_DSN_INFO
3317 , sx.smtp_greeting, sx.helo_response
3318 #endif
3319 );
3320 }
3321
3322
3323 /* If all has gone well, send_quit will be set TRUE, implying we can end the
3324 SMTP session tidily. However, if there were too many addresses to send in one
3325 message (indicated by first_addr being non-NULL) we want to carry on with the
3326 rest of them. Also, it is desirable to send more than one message down the SMTP
3327 connection if there are several waiting, provided we haven't already sent so
3328 many as to hit the configured limit. The function transport_check_waiting looks
3329 for a waiting message and returns its id. Then transport_pass_socket tries to
3330 set up a continued delivery by passing the socket on to another process. The
3331 variable send_rset is FALSE if a message has just been successfully transfered.
3332
3333 If we are already sending down a continued channel, there may be further
3334 addresses not yet delivered that are aimed at the same host, but which have not
3335 been passed in this run of the transport. In this case, continue_more will be
3336 true, and all we should do is send RSET if necessary, and return, leaving the
3337 channel open.
3338
3339 However, if no address was disposed of, i.e. all addresses got 4xx errors, we
3340 do not want to continue with other messages down the same channel, because that
3341 can lead to looping between two or more messages, all with the same,
3342 temporarily failing address(es). [The retry information isn't updated yet, so
3343 new processes keep on trying.] We probably also don't want to try more of this
3344 message's addresses either.
3345
3346 If we have started a TLS session, we have to end it before passing the
3347 connection to a new process. However, not all servers can handle this (Exim
3348 can), so we do not pass such a connection on if the host matches
3349 hosts_nopass_tls. */
3350
3351 DEBUG(D_transport)
3352 debug_printf("ok=%d send_quit=%d send_rset=%d continue_more=%d "
3353 "yield=%d first_address is %sNULL\n", sx.ok, sx.send_quit,
3354 sx.send_rset, continue_more, yield, sx.first_addr ? "not " : "");
3355
3356 if (sx.completed_addr && sx.ok && sx.send_quit)
3357 {
3358 BOOL more;
3359 smtp_compare_t t_compare;
3360
3361 t_compare.tblock = tblock;
3362 t_compare.current_sender_address = sender_address;
3363
3364 if ( sx.first_addr != NULL
3365 || continue_more
3366 || (
3367 #ifdef SUPPORT_TLS
3368 ( tls_out.active < 0 && !continue_proxy_cipher
3369 || verify_check_given_host(&sx.ob->hosts_nopass_tls, host) != OK
3370 )
3371 &&
3372 #endif
3373 transport_check_waiting(tblock->name, host->name,
3374 tblock->connection_max_messages, new_message_id, &more,
3375 (oicf)smtp_are_same_identities, (void*)&t_compare)
3376 ) )
3377 {
3378 uschar *msg;
3379 BOOL pass_message;
3380
3381 if (sx.send_rset)
3382 if (! (sx.ok = smtp_write_command(&sx.outblock, SCMD_FLUSH, "RSET\r\n") >= 0))
3383 {
3384 msg = US string_sprintf("send() to %s [%s] failed: %s", host->name,
3385 host->address, strerror(errno));
3386 sx.send_quit = FALSE;
3387 }
3388 else if (! (sx.ok = smtp_read_response(&sx.inblock, sx.buffer,
3389 sizeof(sx.buffer), '2', sx.ob->command_timeout)))
3390 {
3391 int code;
3392 sx.send_quit = check_response(host, &errno, 0, sx.buffer, &code, &msg,
3393 &pass_message);
3394 if (!sx.send_quit)
3395 {
3396 DEBUG(D_transport) debug_printf("H=%s [%s] %s\n",
3397 host->name, host->address, msg);
3398 }
3399 }
3400
3401 /* Either RSET was not needed, or it succeeded */
3402
3403 if (sx.ok)
3404 {
3405 int pfd[2];
3406 int socket_fd = sx.inblock.sock;
3407
3408
3409 if (sx.first_addr != NULL) /* More addresses still to be sent */
3410 { /* in this run of the transport */
3411 continue_sequence++; /* Causes * in logging */
3412 goto SEND_MESSAGE;
3413 }
3414
3415 /* Unless caller said it already has more messages listed for this host,
3416 pass the connection on to a new Exim process (below, the call to
3417 transport_pass_socket). If the caller has more ready, just return with
3418 the connection still open. */
3419
3420 #ifdef SUPPORT_TLS
3421 if (tls_out.active >= 0)
3422 if ( continue_more
3423 || verify_check_given_host(&sx.ob->hosts_noproxy_tls, host) == OK)
3424 {
3425 /* Before passing the socket on, or returning to caller with it still
3426 open, we must shut down TLS. Not all MTAs allow for the continuation
3427 of the SMTP session when TLS is shut down. We test for this by sending
3428 a new EHLO. If we don't get a good response, we don't attempt to pass
3429 the socket on. */
3430
3431 tls_close(FALSE, TRUE);
3432 smtp_peer_options = smtp_peer_options_wrap;
3433 sx.ok = !sx.smtps
3434 && smtp_write_command(&sx.outblock, SCMD_FLUSH,
3435 "EHLO %s\r\n", sx.helo_data) >= 0
3436 && smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer),
3437 '2', sx.ob->command_timeout);
3438
3439 if (sx.ok && continue_more)
3440 return yield; /* More addresses for another run */
3441 }
3442 else
3443 {
3444 /* Set up a pipe for proxying TLS for the new transport process */
3445
3446 smtp_peer_options |= OPTION_TLS;
3447 if (sx.ok = (socketpair(AF_UNIX, SOCK_STREAM, 0, pfd) == 0))
3448 socket_fd = pfd[1];
3449 else
3450 set_errno(sx.first_addr, errno, US"internal allocation problem",
3451 DEFER, FALSE, host
3452 # ifdef EXPERIMENTAL_DSN_INFO
3453 , sx.smtp_greeting, sx.helo_response
3454 # endif
3455 );
3456 }
3457 else
3458 #endif
3459 if (continue_more)
3460 return yield; /* More addresses for another run */
3461
3462 /* If the socket is successfully passed, we mustn't send QUIT (or
3463 indeed anything!) from here. */
3464
3465 /*XXX DSN_INFO: assume likely to do new HELO; but for greet we'll want to
3466 propagate it from the initial
3467 */
3468 if (sx.ok && transport_pass_socket(tblock->name, host->name,
3469 host->address, new_message_id, socket_fd))
3470 {
3471 sx.send_quit = FALSE;
3472
3473 /* If TLS is still active, we need to proxy it for the transport we
3474 just passed the baton to. Fork a child to to do it, and return to
3475 get logging done asap. Which way to place the work makes assumptions
3476 about post-fork prioritisation which may not hold on all platforms. */
3477 #ifdef SUPPORT_TLS
3478 if (tls_out.active >= 0)
3479 {
3480 int pid = fork();
3481 if (pid > 0) /* parent */
3482 {
3483 DEBUG(D_transport) debug_printf("proxy-proc inter-pid %d\n", pid);
3484 close(pfd[0]);
3485 waitpid(pid, NULL, 0);
3486 tls_close(FALSE, FALSE);
3487 (void)close(sx.inblock.sock);
3488 continue_transport = NULL;
3489 continue_hostname = NULL;
3490 return yield;
3491 }
3492 else if (pid == 0) /* child; fork again to disconnect totally */
3493 {
3494 close(pfd[1]);
3495 if ((pid = fork()))
3496 {
3497 DEBUG(D_transport) debug_printf("proxy-prox final-pid %d\n", pid);
3498 _exit(pid ? EXIT_FAILURE : EXIT_SUCCESS);
3499 }
3500 smtp_proxy_tls(sx.buffer, sizeof(sx.buffer), pfd[0], sx.ob->command_timeout);
3501 exim_exit(0);
3502 }
3503 }
3504 #endif
3505 }
3506 }
3507
3508 /* If RSET failed and there are addresses left, they get deferred. */
3509 else
3510 set_errno(sx.first_addr, errno, msg, DEFER, FALSE, host
3511 #ifdef EXPERIMENTAL_DSN_INFO
3512 , sx.smtp_greeting, sx.helo_response
3513 #endif
3514 );
3515 }
3516 }
3517
3518 /* End off tidily with QUIT unless the connection has died or the socket has
3519 been passed to another process. There has been discussion on the net about what
3520 to do after sending QUIT. The wording of the RFC suggests that it is necessary
3521 to wait for a response, but on the other hand, there isn't anything one can do
3522 with an error response, other than log it. Exim used to do that. However,
3523 further discussion suggested that it is positively advantageous not to wait for
3524 the response, but to close the session immediately. This is supposed to move
3525 the TCP/IP TIME_WAIT state from the server to the client, thereby removing some
3526 load from the server. (Hosts that are both servers and clients may not see much
3527 difference, of course.) Further discussion indicated that this was safe to do
3528 on Unix systems which have decent implementations of TCP/IP that leave the
3529 connection around for a while (TIME_WAIT) after the application has gone away.
3530 This enables the response sent by the server to be properly ACKed rather than
3531 timed out, as can happen on broken TCP/IP implementations on other OS.
3532
3533 This change is being made on 31-Jul-98. After over a year of trouble-free
3534 operation, the old commented-out code was removed on 17-Sep-99. */
3535
3536 SEND_QUIT:
3537 if (sx.send_quit) (void)smtp_write_command(&sx.outblock, SCMD_FLUSH, "QUIT\r\n");
3538
3539 END_OFF:
3540
3541 #ifdef SUPPORT_TLS
3542 tls_close(FALSE, TRUE);
3543 #endif
3544
3545 /* Close the socket, and return the appropriate value, first setting
3546 works because the NULL setting is passed back to the calling process, and
3547 remote_max_parallel is forced to 1 when delivering over an existing connection,
3548
3549 If all went well and continue_more is set, we shouldn't actually get here if
3550 there are further addresses, as the return above will be taken. However,
3551 writing RSET might have failed, or there may be other addresses whose hosts are
3552 specified in the transports, and therefore not visible at top level, in which
3553 case continue_more won't get set. */
3554
3555 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
3556 if (sx.send_quit)
3557 {
3558 shutdown(sx.outblock.sock, SHUT_WR);
3559 if (fcntl(sx.inblock.sock, F_SETFL, O_NONBLOCK) == 0)
3560 for (rc = 16; read(sx.inblock.sock, sx.inbuffer, sizeof(sx.inbuffer)) > 0 && rc > 0;)
3561 rc--; /* drain socket */
3562 }
3563 (void)close(sx.inblock.sock);
3564
3565 #ifndef DISABLE_EVENT
3566 (void) event_raise(tblock->event_action, US"tcp:close", NULL);
3567 #endif
3568
3569 continue_transport = NULL;
3570 continue_hostname = NULL;
3571 return yield;
3572 }
3573
3574
3575
3576
3577 /*************************************************
3578 * Closedown entry point *
3579 *************************************************/
3580
3581 /* This function is called when exim is passed an open smtp channel
3582 from another incarnation, but the message which it has been asked
3583 to deliver no longer exists. The channel is on stdin.
3584
3585 We might do fancy things like looking for another message to send down
3586 the channel, but if the one we sought has gone, it has probably been
3587 delivered by some other process that itself will seek further messages,
3588 so just close down our connection.
3589
3590 Argument: pointer to the transport instance block
3591 Returns: nothing
3592 */
3593
3594 void
3595 smtp_transport_closedown(transport_instance *tblock)
3596 {
3597 smtp_transport_options_block *ob =
3598 (smtp_transport_options_block *)tblock->options_block;
3599 smtp_inblock inblock;
3600 smtp_outblock outblock;
3601 uschar buffer[256];
3602 uschar inbuffer[4096];
3603 uschar outbuffer[16];
3604
3605 inblock.sock = fileno(stdin);
3606 inblock.buffer = inbuffer;
3607 inblock.buffersize = sizeof(inbuffer);
3608 inblock.ptr = inbuffer;
3609 inblock.ptrend = inbuffer;
3610
3611 outblock.sock = inblock.sock;
3612 outblock.buffersize = sizeof(outbuffer);
3613 outblock.buffer = outbuffer;
3614 outblock.ptr = outbuffer;
3615 outblock.cmd_count = 0;
3616 outblock.authenticating = FALSE;
3617
3618 (void)smtp_write_command(&outblock, SCMD_FLUSH, "QUIT\r\n");
3619 (void)smtp_read_response(&inblock, buffer, sizeof(buffer), '2',
3620 ob->command_timeout);
3621 (void)close(inblock.sock);
3622 }
3623
3624
3625
3626 /*************************************************
3627 * Prepare addresses for delivery *
3628 *************************************************/
3629
3630 /* This function is called to flush out error settings from previous delivery
3631 attempts to other hosts. It also records whether we got here via an MX record
3632 or not in the more_errno field of the address. We are interested only in
3633 addresses that are still marked DEFER - others may have got delivered to a
3634 previously considered IP address. Set their status to PENDING_DEFER to indicate
3635 which ones are relevant this time.
3636
3637 Arguments:
3638 addrlist the list of addresses
3639 host the host we are delivering to
3640
3641 Returns: the first address for this delivery
3642 */
3643
3644 static address_item *
3645 prepare_addresses(address_item *addrlist, host_item *host)
3646 {
3647 address_item *first_addr = NULL;
3648 address_item *addr;
3649 for (addr = addrlist; addr; addr = addr->next)
3650 if (addr->transport_return == DEFER)
3651 {
3652 if (!first_addr) first_addr = addr;
3653 addr->transport_return = PENDING_DEFER;
3654 addr->basic_errno = 0;
3655 addr->more_errno = (host->mx >= 0)? 'M' : 'A';
3656 addr->message = NULL;
3657 #ifdef SUPPORT_TLS
3658 addr->cipher = NULL;
3659 addr->ourcert = NULL;
3660 addr->peercert = NULL;
3661 addr->peerdn = NULL;
3662 addr->ocsp = OCSP_NOT_REQ;
3663 #endif
3664 #ifdef EXPERIMENTAL_DSN_INFO
3665 addr->smtp_greeting = NULL;
3666 addr->helo_response = NULL;
3667 #endif
3668 }
3669 return first_addr;
3670 }
3671
3672
3673
3674 /*************************************************
3675 * Main entry point *
3676 *************************************************/
3677
3678 /* See local README for interface details. As this is a remote transport, it is
3679 given a chain of addresses to be delivered in one connection, if possible. It
3680 always returns TRUE, indicating that each address has its own independent
3681 status set, except if there is a setting up problem, in which case it returns
3682 FALSE. */
3683
3684 BOOL
3685 smtp_transport_entry(
3686 transport_instance *tblock, /* data for this instantiation */
3687 address_item *addrlist) /* addresses we are working on */
3688 {
3689 int cutoff_retry;
3690 int defport;
3691 int hosts_defer = 0;
3692 int hosts_fail = 0;
3693 int hosts_looked_up = 0;
3694 int hosts_retry = 0;
3695 int hosts_serial = 0;
3696 int hosts_total = 0;
3697 int total_hosts_tried = 0;
3698 address_item *addr;
3699 BOOL expired = TRUE;
3700 uschar *expanded_hosts = NULL;
3701 uschar *pistring;
3702 uschar *tid = string_sprintf("%s transport", tblock->name);
3703 smtp_transport_options_block *ob =
3704 (smtp_transport_options_block *)(tblock->options_block);
3705 host_item *hostlist = addrlist->host_list;
3706 host_item *host = NULL;
3707
3708 DEBUG(D_transport)
3709 {
3710 debug_printf("%s transport entered\n", tblock->name);
3711 for (addr = addrlist; addr; addr = addr->next)
3712 debug_printf(" %s\n", addr->address);
3713 if (hostlist)
3714 {
3715 debug_printf("hostlist:\n");
3716 for (host = hostlist; host; host = host->next)
3717 debug_printf(" %s:%d\n", host->name, host->port);
3718 }
3719 if (continue_hostname)
3720 debug_printf("already connected to %s [%s] (on fd %d)\n",
3721 continue_hostname, continue_host_address,
3722 cutthrough.fd >= 0 ? cutthrough.fd : 0);
3723 }
3724
3725 /* Set the flag requesting that these hosts be added to the waiting
3726 database if the delivery fails temporarily or if we are running with
3727 queue_smtp or a 2-stage queue run. This gets unset for certain
3728 kinds of error, typically those that are specific to the message. */
3729
3730 update_waiting = TRUE;
3731
3732 /* If a host list is not defined for the addresses - they must all have the
3733 same one in order to be passed to a single transport - or if the transport has
3734 a host list with hosts_override set, use the host list supplied with the
3735 transport. It is an error for this not to exist. */
3736
3737 if (!hostlist || (ob->hosts_override && ob->hosts))
3738 {
3739 if (!ob->hosts)
3740 {
3741 addrlist->message = string_sprintf("%s transport called with no hosts set",
3742 tblock->name);
3743 addrlist->transport_return = PANIC;
3744 return FALSE; /* Only top address has status */
3745 }
3746
3747 DEBUG(D_transport) debug_printf("using the transport's hosts: %s\n",
3748 ob->hosts);
3749
3750 /* If the transport's host list contains no '$' characters, and we are not
3751 randomizing, it is fixed and therefore a chain of hosts can be built once
3752 and for all, and remembered for subsequent use by other calls to this
3753 transport. If, on the other hand, the host list does contain '$', or we are
3754 randomizing its order, we have to rebuild it each time. In the fixed case,
3755 as the hosts string will never be used again, it doesn't matter that we
3756 replace all the : characters with zeros. */
3757
3758 if (!ob->hostlist)
3759 {
3760 uschar *s = ob->hosts;
3761
3762 if (Ustrchr(s, '$') != NULL)
3763 {
3764 if (!(expanded_hosts = expand_string(s)))
3765 {
3766 addrlist->message = string_sprintf("failed to expand list of hosts "
3767 "\"%s\" in %s transport: %s", s, tblock->name, expand_string_message);
3768 addrlist->transport_return = search_find_defer ? DEFER : PANIC;
3769 return FALSE; /* Only top address has status */
3770 }
3771 DEBUG(D_transport) debug_printf("expanded list of hosts \"%s\" to "
3772 "\"%s\"\n", s, expanded_hosts);
3773 s = expanded_hosts;
3774 }
3775 else
3776 if (ob->hosts_randomize) s = expanded_hosts = string_copy(s);
3777
3778 host_build_hostlist(&hostlist, s, ob->hosts_randomize);
3779
3780 /* Check that the expansion yielded something useful. */
3781 if (!hostlist)
3782 {
3783 addrlist->message =
3784 string_sprintf("%s transport has empty hosts setting", tblock->name);
3785 addrlist->transport_return = PANIC;
3786 return FALSE; /* Only top address has status */
3787 }
3788
3789 /* If there was no expansion of hosts, save the host list for
3790 next time. */
3791
3792 if (!expanded_hosts) ob->hostlist = hostlist;
3793 }
3794
3795 /* This is not the first time this transport has been run in this delivery;
3796 the host list was built previously. */
3797
3798 else
3799 hostlist = ob->hostlist;
3800 }
3801
3802 /* The host list was supplied with the address. If hosts_randomize is set, we
3803 must sort it into a random order if it did not come from MX records and has not
3804 already been randomized (but don't bother if continuing down an existing
3805 connection). */
3806
3807 else if (ob->hosts_randomize && hostlist->mx == MX_NONE && !continue_hostname)
3808 {
3809 host_item *newlist = NULL;
3810 while (hostlist)
3811 {
3812 host_item *h = hostlist;
3813 hostlist = hostlist->next;
3814
3815 h->sort_key = random_number(100);
3816
3817 if (!newlist)
3818 {
3819 h->next = NULL;
3820 newlist = h;
3821 }
3822 else if (h->sort_key < newlist->sort_key)
3823 {
3824 h->next = newlist;
3825 newlist = h;
3826 }
3827 else
3828 {
3829 host_item *hh = newlist;
3830 while (hh->next)
3831 {
3832 if (h->sort_key < hh->next->sort_key) break;
3833 hh = hh->next;
3834 }
3835 h->next = hh->next;
3836 hh->next = h;
3837 }
3838 }
3839
3840 hostlist = addrlist->host_list = newlist;
3841 }
3842
3843 /* Sort out the default port. */
3844
3845 if (!smtp_get_port(ob->port, addrlist, &defport, tid)) return FALSE;
3846
3847 /* For each host-plus-IP-address on the list:
3848
3849 . If this is a continued delivery and the host isn't the one with the
3850 current connection, skip.
3851
3852 . If the status is unusable (i.e. previously failed or retry checked), skip.
3853
3854 . If no IP address set, get the address, either by turning the name into
3855 an address, calling gethostbyname if gethostbyname is on, or by calling
3856 the DNS. The DNS may yield multiple addresses, in which case insert the
3857 extra ones into the list.
3858
3859 . Get the retry data if not previously obtained for this address and set the
3860 field which remembers the state of this address. Skip if the retry time is
3861 not reached. If not, remember whether retry data was found. The retry string
3862 contains both the name and the IP address.
3863
3864 . Scan the list of addresses and mark those whose status is DEFER as
3865 PENDING_DEFER. These are the only ones that will be processed in this cycle
3866 of the hosts loop.
3867
3868 . Make a delivery attempt - addresses marked PENDING_DEFER will be tried.
3869 Some addresses may be successfully delivered, others may fail, and yet
3870 others may get temporary errors and so get marked DEFER.
3871
3872 . The return from the delivery attempt is OK if a connection was made and a
3873 valid SMTP dialogue was completed. Otherwise it is DEFER.
3874
3875 . If OK, add a "remove" retry item for this host/IPaddress, if any.
3876
3877 . If fail to connect, or other defer state, add a retry item.
3878
3879 . If there are any addresses whose status is still DEFER, carry on to the
3880 next host/IPaddress, unless we have tried the number of hosts given
3881 by hosts_max_try or hosts_max_try_hardlimit; otherwise return. Note that
3882 there is some fancy logic for hosts_max_try that means its limit can be
3883 overstepped in some circumstances.
3884
3885 If we get to the end of the list, all hosts have deferred at least one address,
3886 or not reached their retry times. If delay_after_cutoff is unset, it requests a
3887 delivery attempt to those hosts whose last try was before the arrival time of
3888 the current message. To cope with this, we have to go round the loop a second
3889 time. After that, set the status and error data for any addresses that haven't
3890 had it set already. */
3891
3892 for (cutoff_retry = 0;
3893 expired && cutoff_retry < (ob->delay_after_cutoff ? 1 : 2);
3894 cutoff_retry++)
3895 {
3896 host_item *nexthost = NULL;
3897 int unexpired_hosts_tried = 0;
3898
3899 for (host = hostlist;
3900 host
3901 && unexpired_hosts_tried < ob->hosts_max_try
3902 && total_hosts_tried < ob->hosts_max_try_hardlimit;
3903 host = nexthost)
3904 {
3905 int rc;
3906 int host_af;
3907 uschar *rs;
3908 BOOL host_is_expired = FALSE;
3909 BOOL message_defer = FALSE;
3910 BOOL some_deferred = FALSE;
3911 address_item *first_addr = NULL;
3912 uschar *interface = NULL;
3913 uschar *retry_host_key = NULL;
3914 uschar *retry_message_key = NULL;
3915 uschar *serialize_key = NULL;
3916
3917 /* Default next host is next host. :-) But this can vary if the
3918 hosts_max_try limit is hit (see below). It may also be reset if a host
3919 address is looked up here (in case the host was multihomed). */
3920
3921 nexthost = host->next;
3922
3923 /* If the address hasn't yet been obtained from the host name, look it up
3924 now, unless the host is already marked as unusable. If it is marked as
3925 unusable, it means that the router was unable to find its IP address (in
3926 the DNS or wherever) OR we are in the 2nd time round the cutoff loop, and
3927 the lookup failed last time. We don't get this far if *all* MX records
3928 point to non-existent hosts; that is treated as a hard error.
3929
3930 We can just skip this host entirely. When the hosts came from the router,
3931 the address will timeout based on the other host(s); when the address is
3932 looked up below, there is an explicit retry record added.
3933
3934 Note that we mustn't skip unusable hosts if the address is not unset; they
3935 may be needed as expired hosts on the 2nd time round the cutoff loop. */
3936
3937 if (!host->address)
3938 {
3939 int new_port, flags;
3940 host_item *hh;
3941
3942 if (host->status >= hstatus_unusable)
3943 {
3944 DEBUG(D_transport) debug_printf("%s has no address and is unusable - skipping\n",
3945 host->name);
3946 continue;
3947 }
3948
3949 DEBUG(D_transport) debug_printf("getting address for %s\n", host->name);
3950
3951 /* The host name is permitted to have an attached port. Find it, and
3952 strip it from the name. Just remember it for now. */
3953
3954 new_port = host_item_get_port(host);
3955
3956 /* Count hosts looked up */
3957
3958 hosts_looked_up++;
3959
3960 /* Find by name if so configured, or if it's an IP address. We don't
3961 just copy the IP address, because we need the test-for-local to happen. */
3962
3963 flags = HOST_FIND_BY_A;
3964 if (ob->dns_qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
3965 if (ob->dns_search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
3966
3967 if (ob->gethostbyname || string_is_ip_address(host->name, NULL) != 0)
3968 rc = host_find_byname(host, NULL, flags, NULL, TRUE);
3969 else
3970 rc = host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
3971 &ob->dnssec, /* domains for request/require */
3972 NULL, NULL);
3973
3974 /* Update the host (and any additional blocks, resulting from
3975 multihoming) with a host-specific port, if any. */
3976
3977 for (hh = host; hh != nexthost; hh = hh->next) hh->port = new_port;
3978
3979 /* Failure to find the host at this time (usually DNS temporary failure)
3980 is really a kind of routing failure rather than a transport failure.
3981 Therefore we add a retry item of the routing kind, not to stop us trying
3982 to look this name up here again, but to ensure the address gets timed
3983 out if the failures go on long enough. A complete failure at this point
3984 commonly points to a configuration error, but the best action is still
3985 to carry on for the next host. */
3986
3987 if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_SECURITY || rc == HOST_FIND_FAILED)
3988 {
3989 retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
3990 expired = FALSE;
3991 if (rc == HOST_FIND_AGAIN) hosts_defer++; else hosts_fail++;
3992 DEBUG(D_transport) debug_printf("rc = %s for %s\n", (rc == HOST_FIND_AGAIN)?
3993 "HOST_FIND_AGAIN" : "HOST_FIND_FAILED", host->name);
3994 host->status = hstatus_unusable;
3995
3996 for (addr = addrlist; addr; addr = addr->next)
3997 {
3998 if (addr->transport_return != DEFER) continue;
3999 addr->basic_errno = ERRNO_UNKNOWNHOST;
4000 addr->message = string_sprintf(
4001 rc == HOST_FIND_SECURITY
4002 ? "lookup of IP address for %s was insecure"
4003 : "failed to lookup IP address for %s",
4004 host->name);
4005 }
4006 continue;
4007 }
4008
4009 /* If the host is actually the local host, we may have a problem, or
4010 there may be some cunning configuration going on. In the problem case,
4011 log things and give up. The default transport status is already DEFER. */
4012
4013 if (rc == HOST_FOUND_LOCAL && !ob->allow_localhost)
4014 {
4015 for (addr = addrlist; addr; addr = addr->next)
4016 {
4017 addr->basic_errno = 0;
4018 addr->message = string_sprintf("%s transport found host %s to be "
4019 "local", tblock->name, host->name);
4020 }
4021 goto END_TRANSPORT;
4022 }
4023 } /* End of block for IP address lookup */
4024
4025 /* If this is a continued delivery, we are interested only in the host
4026 which matches the name of the existing open channel. The check is put
4027 here after the local host lookup, in case the name gets expanded as a
4028 result of the lookup. Set expired FALSE, to save the outer loop executing
4029 twice. */
4030
4031 if ( continue_hostname
4032 && ( Ustrcmp(continue_hostname, host->name) != 0
4033 || Ustrcmp(continue_host_address, host->address) != 0
4034 ) )
4035 {
4036 expired = FALSE;
4037 continue; /* With next host */
4038 }
4039
4040 /* Reset the default next host in case a multihomed host whose addresses
4041 are not looked up till just above added to the host list. */
4042
4043 nexthost = host->next;
4044
4045 /* If queue_smtp is set (-odqs or the first part of a 2-stage run), or the
4046 domain is in queue_smtp_domains, we don't actually want to attempt any
4047 deliveries. When doing a queue run, queue_smtp_domains is always unset. If
4048 there is a lookup defer in queue_smtp_domains, proceed as if the domain
4049 were not in it. We don't want to hold up all SMTP deliveries! Except when
4050 doing a two-stage queue run, don't do this if forcing. */
4051
4052 if ((!deliver_force || queue_2stage) && (queue_smtp ||
4053 match_isinlist(addrlist->domain,
4054 (const uschar **)&queue_smtp_domains, 0,
4055 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK))
4056 {
4057 expired = FALSE;
4058 for (addr = addrlist; addr; addr = addr->next)
4059 if (addr->transport_return == DEFER)
4060 addr->message = US"domain matches queue_smtp_domains, or -odqs set";
4061 continue; /* With next host */
4062 }
4063
4064 /* Count hosts being considered - purely for an intelligent comment
4065 if none are usable. */
4066
4067 hosts_total++;
4068
4069 /* Set $host and $host address now in case they are needed for the
4070 interface expansion or the serialize_hosts check; they remain set if an
4071 actual delivery happens. */
4072
4073 deliver_host = host->name;
4074 deliver_host_address = host->address;
4075 lookup_dnssec_authenticated = host->dnssec == DS_YES ? US"yes"
4076 : host->dnssec == DS_NO ? US"no"
4077 : US"";
4078
4079 /* Set up a string for adding to the retry key if the port number is not
4080 the standard SMTP port. A host may have its own port setting that overrides
4081 the default. */
4082
4083 pistring = string_sprintf(":%d", host->port == PORT_NONE
4084 ? defport : host->port);
4085 if (Ustrcmp(pistring, ":25") == 0) pistring = US"";
4086
4087 /* Select IPv4 or IPv6, and choose an outgoing interface. If the interface
4088 string is set, even if constant (as different transports can have different
4089 constant settings), we must add it to the key that is used for retries,
4090 because connections to the same host from a different interface should be
4091 treated separately. */
4092
4093 host_af = Ustrchr(host->address, ':') == NULL ? AF_INET : AF_INET6;
4094 if ((rs = ob->interface) && *rs)
4095 {
4096 if (!smtp_get_interface(rs, host_af, addrlist, &interface, tid))
4097 return FALSE;
4098 pistring = string_sprintf("%s/%s", pistring, interface);
4099 }
4100
4101 /* The first time round the outer loop, check the status of the host by
4102 inspecting the retry data. The second time round, we are interested only
4103 in expired hosts that haven't been tried since this message arrived. */
4104
4105 if (cutoff_retry == 0)
4106 {
4107 BOOL incl_ip;
4108 /* Ensure the status of the address is set by checking retry data if
4109 necessary. There may be host-specific retry data (applicable to all
4110 messages) and also data for retries of a specific message at this host.
4111 If either of these retry records are actually read, the keys used are
4112 returned to save recomputing them later. */
4113
4114 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
4115 US"retry_include_ip_address", ob->retry_include_ip_address,
4116 ob->expand_retry_include_ip_address, &incl_ip) != OK)
4117 continue; /* with next host */
4118
4119 host_is_expired = retry_check_address(addrlist->domain, host, pistring,
4120 incl_ip, &retry_host_key, &retry_message_key);
4121
4122 DEBUG(D_transport) debug_printf("%s [%s]%s retry-status = %s\n", host->name,
4123 (host->address == NULL)? US"" : host->address, pistring,
4124 (host->status == hstatus_usable)? "usable" :
4125 (host->status == hstatus_unusable)? "unusable" :
4126 (host->status == hstatus_unusable_expired)? "unusable (expired)" : "?");
4127
4128 /* Skip this address if not usable at this time, noting if it wasn't
4129 actually expired, both locally and in the address. */
4130
4131 switch (host->status)
4132 {
4133 case hstatus_unusable:
4134 expired = FALSE;
4135 setflag(addrlist, af_retry_skipped);
4136 /* Fall through */
4137
4138 case hstatus_unusable_expired:
4139 switch (host->why)
4140 {
4141 case hwhy_retry: hosts_retry++; break;
4142 case hwhy_failed: hosts_fail++; break;
4143 case hwhy_insecure:
4144 case hwhy_deferred: hosts_defer++; break;
4145 }
4146
4147 /* If there was a retry message key, implying that previously there
4148 was a message-specific defer, we don't want to update the list of
4149 messages waiting for these hosts. */
4150
4151 if (retry_message_key) update_waiting = FALSE;
4152 continue; /* With the next host or IP address */
4153 }
4154 }
4155
4156 /* Second time round the loop: if the address is set but expired, and
4157 the message is newer than the last try, let it through. */
4158
4159 else
4160 {
4161 if ( !host->address
4162 || host->status != hstatus_unusable_expired
4163 || host->last_try > received_time)
4164 continue;
4165 DEBUG(D_transport) debug_printf("trying expired host %s [%s]%s\n",
4166 host->name, host->address, pistring);
4167 host_is_expired = TRUE;
4168 }
4169
4170 /* Setting "expired=FALSE" doesn't actually mean not all hosts are expired;
4171 it remains TRUE only if all hosts are expired and none are actually tried.
4172 */
4173
4174 expired = FALSE;
4175
4176 /* If this host is listed as one to which access must be serialized,
4177 see if another Exim process has a connection to it, and if so, skip
4178 this host. If not, update the database to record our connection to it
4179 and remember this for later deletion. Do not do any of this if we are
4180 sending the message down a pre-existing connection. */
4181
4182 if ( !continue_hostname
4183 && verify_check_given_host(&ob->serialize_hosts, host) == OK)
4184 {
4185 serialize_key = string_sprintf("host-serialize-%s", host->name);
4186 if (!enq_start(serialize_key, 1))
4187 {
4188 DEBUG(D_transport)
4189 debug_printf("skipping host %s because another Exim process "
4190 "is connected to it\n", host->name);
4191 hosts_serial++;
4192 continue;
4193 }
4194 }
4195
4196 /* OK, we have an IP address that is not waiting for its retry time to
4197 arrive (it might be expired) OR (second time round the loop) we have an
4198 expired host that hasn't been tried since the message arrived. Have a go
4199 at delivering the message to it. First prepare the addresses by flushing
4200 out the result of previous attempts, and finding the first address that
4201 is still to be delivered. */
4202
4203 first_addr = prepare_addresses(addrlist, host);
4204
4205 DEBUG(D_transport) debug_printf("delivering %s to %s [%s] (%s%s)\n",
4206 message_id, host->name, host->address, addrlist->address,
4207 addrlist->next ? ", ..." : "");
4208
4209 set_process_info("delivering %s to %s [%s] (%s%s)",
4210 message_id, host->name, host->address, addrlist->address,
4211 addrlist->next ? ", ..." : "");
4212
4213 /* This is not for real; don't do the delivery. If there are
4214 any remaining hosts, list them. */
4215
4216 if (dont_deliver)
4217 {
4218 host_item *host2;
4219 set_errno_nohost(addrlist, 0, NULL, OK, FALSE);
4220 for (addr = addrlist; addr; addr = addr->next)
4221 {
4222 addr->host_used = host;
4223 addr->special_action = '*';
4224 addr->message = US"delivery bypassed by -N option";
4225 }
4226 DEBUG(D_transport)
4227 {
4228 debug_printf("*** delivery by %s transport bypassed by -N option\n"
4229 "*** host and remaining hosts:\n", tblock->name);
4230 for (host2 = host; host2; host2 = host2->next)
4231 debug_printf(" %s [%s]\n", host2->name,
4232 host2->address ? host2->address : US"unset");
4233 }
4234 rc = OK;
4235 }
4236
4237 /* This is for real. If the host is expired, we don't count it for
4238 hosts_max_retry. This ensures that all hosts must expire before an address
4239 is timed out, unless hosts_max_try_hardlimit (which protects against
4240 lunatic DNS configurations) is reached.
4241
4242 If the host is not expired and we are about to hit the hosts_max_retry
4243 limit, check to see if there is a subsequent hosts with a different MX
4244 value. If so, make that the next host, and don't count this one. This is a
4245 heuristic to make sure that different MXs do get tried. With a normal kind
4246 of retry rule, they would get tried anyway when the earlier hosts were
4247 delayed, but if the domain has a "retry every time" type of rule - as is
4248 often used for the the very large ISPs, that won't happen. */
4249
4250 else
4251 {
4252 host_item * thost;
4253 /* Make a copy of the host if it is local to this invocation
4254 of the transport. */
4255
4256 if (expanded_hosts)
4257 {
4258 thost = store_get(sizeof(host_item));
4259 *thost = *host;
4260 thost->name = string_copy(host->name);
4261 thost->address = string_copy(host->address);
4262 }
4263 else
4264 thost = host;
4265
4266 if (!host_is_expired && ++unexpired_hosts_tried >= ob->hosts_max_try)
4267 {
4268 host_item *h;
4269 DEBUG(D_transport)
4270 debug_printf("hosts_max_try limit reached with this host\n");
4271 for (h = host; h; h = h->next) if (h->mx != host->mx)
4272 {
4273 nexthost = h;
4274 unexpired_hosts_tried--;
4275 DEBUG(D_transport) debug_printf("however, a higher MX host exists "
4276 "and will be tried\n");
4277 break;
4278 }
4279 }
4280
4281 /* Attempt the delivery. */
4282
4283 total_hosts_tried++;
4284 rc = smtp_deliver(addrlist, thost, host_af, defport, interface, tblock,
4285 &message_defer, FALSE);
4286
4287 /* Yield is one of:
4288 OK => connection made, each address contains its result;
4289 message_defer is set for message-specific defers (when all
4290 recipients are marked defer)
4291 DEFER => there was a non-message-specific delivery problem;
4292 ERROR => there was a problem setting up the arguments for a filter,
4293 or there was a problem with expanding added headers
4294 */
4295
4296 /* If the result is not OK, there was a non-message-specific problem.
4297 If the result is DEFER, we need to write to the logs saying what happened
4298 for this particular host, except in the case of authentication and TLS
4299 failures, where the log has already been written. If all hosts defer a
4300 general message is written at the end. */
4301
4302 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL
4303 && first_addr->basic_errno != ERRNO_TLSFAILURE)
4304 write_logs(first_addr, host);
4305
4306 #ifndef DISABLE_EVENT
4307 if (rc == DEFER)
4308 deferred_event_raise(first_addr, host);
4309 #endif
4310
4311 /* If STARTTLS was accepted, but there was a failure in setting up the
4312 TLS session (usually a certificate screwup), and the host is not in
4313 hosts_require_tls, and tls_tempfail_tryclear is true, try again, with
4314 TLS forcibly turned off. We have to start from scratch with a new SMTP
4315 connection. That's why the retry is done from here, not from within
4316 smtp_deliver(). [Rejections of STARTTLS itself don't screw up the
4317 session, so the in-clear transmission after those errors, if permitted,
4318 happens inside smtp_deliver().] */
4319
4320 #ifdef SUPPORT_TLS
4321 if ( rc == DEFER
4322 && first_addr->basic_errno == ERRNO_TLSFAILURE
4323 && ob->tls_tempfail_tryclear
4324 && verify_check_given_host(&ob->hosts_require_tls, host) != OK
4325 )
4326 {
4327 log_write(0, LOG_MAIN,
4328 "%s: delivering unencrypted to H=%s [%s] (not in hosts_require_tls)",
4329 first_addr->message, host->name, host->address);
4330 first_addr = prepare_addresses(addrlist, host);
4331 rc = smtp_deliver(addrlist, thost, host_af, defport, interface, tblock,
4332 &message_defer, TRUE);
4333 if (rc == DEFER && first_addr->basic_errno != ERRNO_AUTHFAIL)
4334 write_logs(first_addr, host);
4335 # ifndef DISABLE_EVENT
4336 if (rc == DEFER)
4337 deferred_event_raise(first_addr, host);
4338 # endif
4339 }
4340 #endif /*SUPPORT_TLS*/
4341 }
4342
4343 /* Delivery attempt finished */
4344
4345 rs = rc == OK ? US"OK"
4346 : rc == DEFER ? US"DEFER"
4347 : rc == ERROR ? US"ERROR"
4348 : US"?";
4349
4350 set_process_info("delivering %s: just tried %s [%s] for %s%s: result %s",
4351 message_id, host->name, host->address, addrlist->address,
4352 addrlist->next ? " (& others)" : "", rs);
4353
4354 /* Release serialization if set up */
4355
4356 if (serialize_key) enq_end(serialize_key);
4357
4358 /* If the result is DEFER, or if a host retry record is known to exist, we
4359 need to add an item to the retry chain for updating the retry database
4360 at the end of delivery. We only need to add the item to the top address,
4361 of course. Also, if DEFER, we mark the IP address unusable so as to skip it
4362 for any other delivery attempts using the same address. (It is copied into
4363 the unusable tree at the outer level, so even if different address blocks
4364 contain the same address, it still won't get tried again.) */
4365
4366 if (rc == DEFER || retry_host_key)
4367 {
4368 int delete_flag = rc != DEFER ? rf_delete : 0;
4369 if (!retry_host_key)
4370 {
4371 BOOL incl_ip;
4372 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
4373 US"retry_include_ip_address", ob->retry_include_ip_address,
4374 ob->expand_retry_include_ip_address, &incl_ip) != OK)
4375 incl_ip = TRUE; /* error; use most-specific retry record */
4376
4377 retry_host_key = incl_ip
4378 ? string_sprintf("T:%S:%s%s", host->name, host->address, pistring)
4379 : string_sprintf("T:%S%s", host->name, pistring);
4380 }
4381
4382 /* If a delivery of another message over an existing SMTP connection
4383 yields DEFER, we do NOT set up retry data for the host. This covers the
4384 case when there are delays in routing the addresses in the second message
4385 that are so long that the server times out. This is alleviated by not
4386 routing addresses that previously had routing defers when handling an
4387 existing connection, but even so, this case may occur (e.g. if a
4388 previously happily routed address starts giving routing defers). If the
4389 host is genuinely down, another non-continued message delivery will
4390 notice it soon enough. */
4391
4392 if (delete_flag != 0 || !continue_hostname)
4393 retry_add_item(first_addr, retry_host_key, rf_host | delete_flag);
4394
4395 /* We may have tried an expired host, if its retry time has come; ensure
4396 the status reflects the expiry for the benefit of any other addresses. */
4397
4398 if (rc == DEFER)
4399 {
4400 host->status = host_is_expired
4401 ? hstatus_unusable_expired : hstatus_unusable;
4402 host->why = hwhy_deferred;
4403 }
4404 }
4405
4406 /* If message_defer is set (host was OK, but every recipient got deferred
4407 because of some message-specific problem), or if that had happened
4408 previously so that a message retry key exists, add an appropriate item
4409 to the retry chain. Note that if there was a message defer but now there is
4410 a host defer, the message defer record gets deleted. That seems perfectly
4411 reasonable. Also, stop the message from being remembered as waiting
4412 for specific hosts. */
4413
4414 if (message_defer || retry_message_key)
4415 {
4416 int delete_flag = message_defer ? 0 : rf_delete;
4417 if (!retry_message_key)
4418 {
4419 BOOL incl_ip;
4420 if (exp_bool(addrlist, US"transport", tblock->name, D_transport,
4421 US"retry_include_ip_address", ob->retry_include_ip_address,
4422 ob->expand_retry_include_ip_address, &incl_ip) != OK)
4423 incl_ip = TRUE; /* error; use most-specific retry record */
4424
4425 retry_message_key = incl_ip
4426 ? string_sprintf("T:%S:%s%s:%s", host->name, host->address, pistring,
4427 message_id)
4428 : string_sprintf("T:%S%s:%s", host->name, pistring, message_id);
4429 }
4430 retry_add_item(addrlist, retry_message_key,
4431 rf_message | rf_host | delete_flag);
4432 update_waiting = FALSE;
4433 }
4434
4435 /* Any return other than DEFER (that is, OK or ERROR) means that the
4436 addresses have got their final statuses filled in for this host. In the OK
4437 case, see if any of them are deferred. */
4438
4439 if (rc == OK)
4440 for (addr = addrlist; addr; addr = addr->next)
4441 if (addr->transport_return == DEFER)
4442 {
4443 some_deferred = TRUE;
4444 break;
4445 }
4446
4447 /* If no addresses deferred or the result was ERROR, return. We do this for
4448 ERROR because a failing filter set-up or add_headers expansion is likely to
4449 fail for any host we try. */
4450
4451 if (rc == ERROR || (rc == OK && !some_deferred))
4452 {
4453 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
4454 return TRUE; /* Each address has its status */
4455 }
4456
4457 /* If the result was DEFER or some individual addresses deferred, let
4458 the loop run to try other hosts with the deferred addresses, except for the
4459 case when we were trying to deliver down an existing channel and failed.
4460 Don't try any other hosts in this case. */
4461
4462 if (continue_hostname) break;
4463
4464 /* If the whole delivery, or some individual addresses, were deferred and
4465 there are more hosts that could be tried, do not count this host towards
4466 the hosts_max_try limit if the age of the message is greater than the
4467 maximum retry time for this host. This means we may try try all hosts,
4468 ignoring the limit, when messages have been around for some time. This is
4469 important because if we don't try all hosts, the address will never time
4470 out. NOTE: this does not apply to hosts_max_try_hardlimit. */
4471
4472 if ((rc == DEFER || some_deferred) && nexthost)
4473 {
4474 BOOL timedout;
4475 retry_config *retry = retry_find_config(host->name, NULL, 0, 0);
4476
4477 if (retry && retry->rules)
4478 {
4479 retry_rule *last_rule;
4480 for (last_rule = retry->rules;
4481 last_rule->next;
4482 last_rule = last_rule->next);
4483 timedout = time(NULL) - received_time > last_rule->timeout;
4484 }
4485 else timedout = TRUE; /* No rule => timed out */
4486
4487 if (timedout)
4488 {
4489 unexpired_hosts_tried--;
4490 DEBUG(D_transport) debug_printf("temporary delivery error(s) override "
4491 "hosts_max_try (message older than host's retry time)\n");
4492 }
4493 }
4494 } /* End of loop for trying multiple hosts. */
4495
4496 /* This is the end of the loop that repeats iff expired is TRUE and
4497 ob->delay_after_cutoff is FALSE. The second time round we will
4498 try those hosts that haven't been tried since the message arrived. */
4499
4500 DEBUG(D_transport)
4501 {
4502 debug_printf("all IP addresses skipped or deferred at least one address\n");
4503 if (expired && !ob->delay_after_cutoff && cutoff_retry == 0)
4504 debug_printf("retrying IP addresses not tried since message arrived\n");
4505 }
4506 }
4507
4508
4509 /* Get here if all IP addresses are skipped or defer at least one address. In
4510 MUA wrapper mode, this will happen only for connection or other non-message-
4511 specific failures. Force the delivery status for all addresses to FAIL. */
4512
4513 if (mua_wrapper)
4514 {
4515 for (addr = addrlist; addr; addr = addr->next)
4516 addr->transport_return = FAIL;
4517 goto END_TRANSPORT;
4518 }
4519
4520 /* In the normal, non-wrapper case, add a standard message to each deferred
4521 address if there hasn't been an error, that is, if it hasn't actually been
4522 tried this time. The variable "expired" will be FALSE if any deliveries were
4523 actually tried, or if there was at least one host that was not expired. That
4524 is, it is TRUE only if no deliveries were tried and all hosts were expired. If
4525 a delivery has been tried, an error code will be set, and the failing of the
4526 message is handled by the retry code later.
4527
4528 If queue_smtp is set, or this transport was called to send a subsequent message
4529 down an existing TCP/IP connection, and something caused the host not to be
4530 found, we end up here, but can detect these cases and handle them specially. */
4531
4532 for (addr = addrlist; addr; addr = addr->next)
4533 {
4534 /* If host is not NULL, it means that we stopped processing the host list
4535 because of hosts_max_try or hosts_max_try_hardlimit. In the former case, this
4536 means we need to behave as if some hosts were skipped because their retry
4537 time had not come. Specifically, this prevents the address from timing out.
4538 However, if we have hit hosts_max_try_hardlimit, we want to behave as if all
4539 hosts were tried. */
4540
4541 if (host)
4542 if (total_hosts_tried >= ob->hosts_max_try_hardlimit)
4543 {
4544 DEBUG(D_transport)
4545 debug_printf("hosts_max_try_hardlimit reached: behave as if all "
4546 "hosts were tried\n");
4547 }
4548 else
4549 {
4550 DEBUG(D_transport)
4551 debug_printf("hosts_max_try limit caused some hosts to be skipped\n");
4552 setflag(addr, af_retry_skipped);
4553 }
4554
4555 if (queue_smtp) /* no deliveries attempted */
4556 {
4557 addr->transport_return = DEFER;
4558 addr->basic_errno = 0;
4559 addr->message = US"SMTP delivery explicitly queued";
4560 }
4561
4562 else if ( addr->transport_return == DEFER
4563 && (addr->basic_errno == ERRNO_UNKNOWNERROR || addr->basic_errno == 0)
4564 && !addr->message
4565 )
4566 {
4567 addr->basic_errno = ERRNO_HRETRY;
4568 if (continue_hostname)
4569 addr->message = US"no host found for existing SMTP connection";
4570 else if (expired)
4571 {
4572 setflag(addr, af_pass_message); /* This is not a security risk */
4573 addr->message = string_sprintf(
4574 "all hosts%s have been failing for a long time %s",
4575 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"",
4576 ob->delay_after_cutoff
4577 ? US"(and retry time not reached)"
4578 : US"and were last tried after this message arrived");
4579
4580 /* If we are already using fallback hosts, or there are no fallback hosts
4581 defined, convert the result to FAIL to cause a bounce. */
4582
4583 if (addr->host_list == addr->fallback_hosts || !addr->fallback_hosts)
4584 addr->transport_return = FAIL;
4585 }
4586 else
4587 {
4588 const char * s;
4589 if (hosts_retry == hosts_total)
4590 s = "retry time not reached for any host%s";
4591 else if (hosts_fail == hosts_total)
4592 s = "all host address lookups%s failed permanently";
4593 else if (hosts_defer == hosts_total)
4594 s = "all host address lookups%s failed temporarily";
4595 else if (hosts_serial == hosts_total)
4596 s = "connection limit reached for all hosts%s";
4597 else if (hosts_fail+hosts_defer == hosts_total)
4598 s = "all host address lookups%s failed";
4599 else
4600 s = "some host address lookups failed and retry time "
4601 "not reached for other hosts or connection limit reached%s";
4602
4603 addr->message = string_sprintf(s,
4604 addr->domain ? string_sprintf(" for '%s'", addr->domain) : US"");
4605 }
4606 }
4607 }
4608
4609 /* Update the database which keeps information about which messages are waiting
4610 for which hosts to become available. For some message-specific errors, the
4611 update_waiting flag is turned off because we don't want follow-on deliveries in
4612 those cases. If this transport instance is explicitly limited to one message
4613 per connection then follow-on deliveries are not possible and there's no need
4614 to create/update the per-transport wait-<transport_name> database. */
4615
4616 if (update_waiting && tblock->connection_max_messages != 1)
4617 transport_update_waiting(hostlist, tblock->name);
4618
4619 END_TRANSPORT:
4620
4621 DEBUG(D_transport) debug_printf("Leaving %s transport\n", tblock->name);
4622
4623 return TRUE; /* Each address has its status */
4624 }
4625
4626 #endif /*!MACRO_PREDEF*/
4627 /* vi: aw ai sw=2
4628 */
4629 /* End of transport/smtp.c */
Unnamed repository; edit this file 'description' to name the repository.